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purification, sequencing and structural characterization of the phospholipase a1 from the venom of the social wasp polybia paulista (hymenoptera, vespidae).the biochemical and functional characterization of wasp venom toxins is an important prerequisite for the development of new tools both for the therapy of the toxic reactions due to envenomation caused by multiple stinging accidents and also for the diagnosis and therapy of allergic reactions caused by this type of venom. pla(1) was purified from the venom of the neotropical social wasp polybia paulista by using molecular exclusion and cation exchange chromatographies; its amino acid sequence wa ...200717761205
new biological activity against phospholipase a2 by turmerin, a protein from curcuma longa l.turmerin is a protein from turmeric (curcuma longa l.) with a relative molecular mass of 14 kda. the protein inhibits the enzymatic activity and neutralizes the pharmacological properties, such as cytotoxicity, oedema and myotoxicity of multitoxic phospholipase a2 (nv-pla2) of cobra (naja naja) venom at a 1:2.5 molar ratio of nv-pla2:turmerin. a lineweaver-burk plot indicates that turmerin follows a linear mixed type of inhibition.200818177267
taiwan cobra cardiotoxins induce apoptotic death of human neuroblastoma sk-n-sh cells mediated by reactive oxygen species generation and mitochondrial depolarization.although naja naja atra cardiotoxin 3 (ctx3) and cardiotoxin 4 (ctx4) showed different cytotoxicity toward human neuroblastoma sk-n-sh cells, the two toxins induced apoptotic death on sk-n-sh cells. the apoptosis signals of ctx3 and ctx3 included ros generation, increase in mitochondrial permeability transition, cytochrome c release to the cytosol and activation of caspase-9 and -3. however, ctx3 quickly induced the effects with higher magnitude compared with ctx4. ros production and subsequent ...200818221763
cardiotoxin iii-induced apoptosis is mediated by ca2+-dependent caspase-12 activation in k562 cells.cardiotoxin iii (ctx iii), a basic polypeptide with 60 amino acid residues isolated from naja naja atra venom, has been reported to have anticancer activity. when k562 cells were treated with ctx iii, cytosolic calcium concentration was rapidly and persistently increased. this ctx iii-induced cell death was partially reversed by pretreatment with bapta/am (20 microm), a chelator of intracellular ca2+. moreover, ctx iii-induced apoptotic signals, such as caspase-12 and c-jun n-terminal kinase (jn ...200818561336
isolation of a snake venom phospholipase a2 (pla2) inhibitor (aiplai) from leaves of azadirachta indica (neem): mechanism of pla2 inhibition by aiplai in vitro condition.a compound (aiplai (azadirachta indica pla(2) inhibitor)) purified from the methanolic leaf extract of a. indica (neem) inhibits the cobra and russell's viper venoms (rvvs) phospholipase a(2) enzymes in a dose-dependent manner. inhibition of catalytic and tested pharmacological properties of cobra venom (naja naja and naja kaouthia) pla(2) enzymes by aiplai is significantly higher (p<0.05) compared to the inhibition of pla(2) enzymes of crude rvv (daboia russelli) when tested under the same cond ...200818466944
cardiotoxin iii induces c-jun n-terminal kinase-dependent apoptosis in hl-60 human leukaemia cells.cardiotoxin iii (ctx iii), a basic polypeptide with 60 amino acid residues isolated from naja naja atra venom, has been reported to have anticancer activity. the molecular effects of ctx iii on hl-60 cells were dissected in the present study. we found that the antiproliferative action of ctx iii on hl-60 cells was mediated through apoptosis, as characterized by an increase of sub g1 population, dna fragmentation and poly(adp-ribose) polymerase (parp) cleavage. upregulation of bax, downregulation ...200817514639
p38 mapk activation and mitochondrial depolarization mediate the cytotoxicity of taiwan cobra phospholipase a2 on human neuroblastoma sk-n-sh cells.modification of catalytic residue his-47 with p-bromophenacyl bromide (bpb) abolished the enzymatic activity of naja naja atra phospholipase a2 (pla2). additionally, alterations in the global structure and the spatial positions of trp residues were noted in his-modified pla2. the cell viability of human neuroblastoma sk-n-sh cells was decreased by approximately 40% and 20% after treatment with 10 microm pla2 and bpb-pla2, respectively. native and his-modified pla2 induced a necrotic cell death a ...200818582542
neutralization of the pharmacological effects of cobra and krait venoms by chicken egg yolk antibodies.five-month-old white leghorn chickens were immunized with 50 microg of common cobra (naja naja) and 30 microg of krait venoms (bungarus caeruleus) to generate antivenom antibodies against the venom antigen. chickens received booster doses of increasing concentrations of venom at 14 days time intervals to raise the antivenom level in egg yolk. the antivenom from immunized chicken egg yolk was extracted by polyethylene glycol (peg) and ammonium sulphate precipitation method which was further purif ...200818590753
involvement of mitochondrial alteration and reactive oxygen species generation in taiwan cobra cardiotoxin-induced apoptotic death of human neuroblastoma sk-n-sh cells.naja naja atra cardiotoxin 3 (ctx3) induced apoptotic death on human neuroblastoma sk-n-sh cells. the apoptosis signals of ctx3 included reactive oxygen species (ros) generation, disruption of mitochondrial membrane potential (deltapsim), cytochrome c release to the cytosol and activation of caspase-9 and -3. however, ctx3-induced increase in mitochondrial permeability transition was not initiated by proteins of the bcl-2 family. the collapse of deltapsim, release of cytosolic cytochrome c, prod ...200818619991
increase of the cytotoxic effect of bothrops jararacussu venom on mouse extensor digitorum longus and soleus by potassium channel blockers and by na(+)/k(+)-atpase inhibition.we investigated the myotoxicity of bothrops jararacussu crude venom and other cytolytic agents on mouse isolated extensor digitorum longus (edl) and soleus (sol) muscles, which present distinct properties: edl is a fast-twitch, white muscle with predominantly glycolytic fibers, while sol is slow-twitch, red muscle with predominantly oxidative fibers. muscles were exposed to b. jararacussu crude venom (25 microg/ml) and other crotaline venoms (agkistrodon contortrix laticinctus; crotalus viridis ...200818675839
inn-toxin, a highly lethal peptide from the venom of indian cobra (naja naja) venom-isolation, characterization and pharmacological actions.a novel toxic polypeptide, inn-toxin, is purified from the venom of naja naja using combination of gel-permeation and ion-exchange chromatography. it has a molecular mass of 6951.6da as determined by maldi-tof/ms and the n-terminal sequence of lkxnklvplf. it showed both neurotoxic as well as cytotoxic activities. inn-toxin is lethal to mice with a ld(50) of 1.2mg/kg body weight. igy raised in chicks against basic peptide pool neutralized the toxicity of inn-toxin. inn-toxin did not inhibit choli ...200818760317
the structural and functional contribution of n-terminal region and his-47 on taiwan cobra phospholipase a2.modification of his-47 and removal of the n-terminal octapeptide caused a different effect on the structure of naja naja atra (taiwan cobra) phospholipase a2 (pla2). unlike native enzyme, ca2+ induced an alteration in the structural flexibility of his-modified pla2. moreover, the spatial positions of trp residues in his-modified pla2 were not properly rearranged toward lipid-water interface in the presence of ca2+. cd spectra and fluorescence measurement showed that the dynamic properties of trp ...200818008383
mutations on the n-terminal region abolish differentially the enzymatic activity, membrane-damaging activity and cytotoxicity of taiwan cobra phospholipase a2.to examine the functional contribution of the n-terminal region to the activities of naja naja atra phospholipase a(2) (pla(2)), studies on three n-terminally mutated pla(2) were carried out in the present work. removal of n-terminal heptapeptide caused a complete loss of membrane-damaging activity, whilst the mutants with an extra met before asn-1 or substituting asn-1 with met still retained approximately 40.9% and 82.9% membrane-damaging activity of the native enzyme, respectively. mutations ...200818022206
l-amino acid oxidase from naja naja oxiana venom.a new l-amino acid oxidase (laao) was isolated from the central asian cobra naja naja oxiana venom by size exclusion, ion exchange and hydrophobic chromatography. the n-terminal sequence and the internal peptide sequences share high similarity with other snake venom l-amino acid oxidases, especially with those isolated from elapid venoms. the enzyme is stable at low temperatures (-20 degrees c, -70 degrees c) and loses its activity by heating at 70 degrees c. specific substrates for the isolated ...200818294891
involvement of both endoplasmic reticulum- and mitochondria-dependent pathways in cardiotoxin iii-induced apoptosis in hl-60 cells.cardiotoxin (ctx) iii, a basic polypeptide with 60 amino acid residues isolated from naja naja atra venom, has been reported to have anticancer activity. in the present study, we investigated the mechanisms underlying the anticancer activity of ctx iii in human leukaemia (hl-60 cells). cardiotoxin iii activated the endoplasmic reticulum (er) pathway of apoptosis in hl-60 cells, as indicated by increased levels of calcium and glucose-related protein 78 (grp78), and triggered the subsequent activa ...200818505440
purification and characterization of a novel antinociceptive toxin from cobra venom (naja naja atra).snake venoms have demonstrated antinociceptive activity, and certain isolated neurotoxins have demonstrated significant analgesia in animal models. here we report a novel analgesic toxin which was isolated from naja naja atra and was given the name 'najanalgesin'. the ld(50) of the crude venom and najanalgesin were 0.89mg/kg and 2.69mg/kg, respectively. we used the writhing test and hot plate test to evaluate the antinociceptive properties of the crude venom and najanalgesin after intraperitonea ...200818765245
isolation, purification, crystallization and preliminary crystallographic studies of sagitoxin, an oligomeric cardiotoxin from the venom of naja naja saggitifera.sagitoxin, a novel cardiotoxin from the venom of naja naja saggitifera, has been successfully isolated, purified to homogeneity and crystallized. the toxin was purified using successive separation steps on a cm-sephadex c-50 column and a reverse-phase column. the 6.75 kda toxin was sequenced by the edman method using a ppsq-21 protein sequencer. it was crystallized using the hanging-drop vapour-diffusion method. the hexagonal-shaped crystals diffracted to 3.0 a resolution and belonged to space g ...200818540072
interaction of group ia phospholipase a2 with metal ions and phospholipid vesicles probed with deuterium exchange mass spectrometry.deuterium exchange mass spectrometric evaluation of the cobra venom (naja naja naja) group ia phospholipase a 2 (gia pla 2) was carried out in the presence of metal ions ca (2+) and ba (2+) and phospholipid vesicles. novel conditions for digesting highly disulfide bonded proteins and a methodology for studying protein-lipid interactions using deuterium exchange have been developed. the enzyme exhibits unexpectedly slow rates of exchange in the two large alpha-helices of residues 43-53 and 89-101 ...200818500818
antioxidants: promising neuroprotection against cardiotoxin-4b-induced cell death which triggers oxidative stress with early calpain activation.cardiotoxin-4b (ctx-4b), isolated from naja naja sputatrix venom, shows lethality in several cell types. employing murine primary cortical neurons, this study was undertaken to investigate the molecular mechanisms of ctx-4b in the induction of neuronal death. ctx-4b induced a dose- and time-dependent neuronal death. strong induction of calpains as early as 4h post-ctx-4b 75 nm treatment was detected in neurons with negligible caspase 3 activation. for the first time in cultured murine primary co ...200818377942
loop 3 of short neurotoxin ii is an additional interaction site with membrane-bound nicotinic acetylcholine receptor as detected by solid-state nmr spectroscopy.the contact area of neurotoxin ii from naja naja oxiana when interacting with the membrane-bound nicotinic acetylcholine receptor from torpedo californica was determined by solid-state, magic-angle spinning nmr spectroscopy. for this purpose, the carbon signals for more than 90% of the residues of the bound neurotoxin were assigned. differences between the solution and solid-state chemical shifts of the free and bound form of the toxin are confined to distinct surface regions. loop ii of the sho ...200919447114
epidemiology, clinical profile and management issues of cobra (naja naja) bites in sri lanka: first authenticated case series.in sri lanka, the spectacled cobra (naja naja) inflicts fatal bites. this hospital-based prospective study describes 25 cases of proven cobra bites, including 10 (40%) males and 15 (60%) females with a median age of 36 years (range 13-70 years). in 22 cases (88%) bites occurred in the daytime and in 13 cases (52%) they occurred at the victim's home compound. the site of the bite was the upper limb in 10 cases (40%), and 12 patients (48%) had applied a tourniquet. there were 5 dry bites (20%), 20 ...200919439335
consensus sequence l/pkssll mimics crucial epitope on loop iii of taiwan cobra cardiotoxin.phage display is effective in screening peptides that mimic venom's neutralizing epitopes. a phage display cyclized heptapeptide library (c7c library) was panned with purified divalent antivenin igg, which neutralizes naja naja atra venom (nav) and bungarus multicinctus venom (bmv). the selected heptapeptide sequences were aligned with known protein sequences of nav and bmv in genbank. one of the four consensus sequences, l/pkssll, mimicked the crucial epitope on loop iii of taiwan cobra cardiot ...200919632196
inactivation of epidermal growth factor receptor and downstream pathways in oral squamous cell carcinoma ca9-22 cells by cardiotoxin iii from naja naja atra.cardiotoxin iii (1), a basic polypeptide with 60 amino acid residues isolated from naja naja atra venom, has potential therapeutic activity in cancer. treatment with 1 reduced phosphorylation of egfr and akt, as well as erk in ca9-22 cells. moreover, 1-treatment inhibited constitutive activation of stat3 and stat5 in a time-dependent manner. up-regulation of bax and down-regulation of anti-apoptotic proteins including bcl-2, bcl-x(l), and myeloid cell leukemia-1(mcl-1) were also found in cells t ...200919754129
differential binding to phospholipid bilayers modulates membrane-damaging activity of naja naja atra cardiotoxins.to address the events that modulate membrane-damaging activity of naja naja atra cardiotoxins (ctxs), the present study was carried out. it was found that ctx isotoxins showed different activities in inducing leakage of vesicles made of egg yolk phosphatidylcholine (eypc)/dimyristoyl phosphatidic acid (dmpa) or eypc/egg yolk sphingomyelin (eysm). although ctxs had different gross conformations, the toxins showed similar binding affinity for phospholipid vesicles. topographical contact between to ...200919450618
[isolation and pharmacological properties of analgesic fraction from venom of naja naja atra].to separate main analgesic fraction from venom of guangdong naja naja atra, to establish the basis for the using of naja naja atra and find new analgesic fraction.200919873725
apoptosis of human hepatocellular carcinoma cell (hepg2) induced by cardiotoxin iii through s-phase arrest.cytotoxin iii (ctx iii), a basic polypeptide with 60 amino acid residues isolated from naja naja atra venom, have potential therapeutic activity in tumor therapy. however, the therapeutic effect in solid tumor treatment with ctx iii are still largely unknown. in the present study, we investigated whether ctx iii affects cell growth and cell cycle progression of hepatocellular carcinoma cell (hepg2). we found that the proliferation of hepg2 cell was inhibited by ctx iii, to some extent, in a time ...200918986802
upregulation of fas and fasl in taiwan cobra phospholipase a2-treated human neuroblastoma sk-n-sh cells through ros- and ca2+-mediated p38 mapk activation.the aim of the present study is to elucidate the signaling pathway involved in death of human neuroblastoma sk-n-sh cells induced by naja naja atra phospholipase a(2) (pla(2)). upon exposure to pla(2), p38 mapk activation, erk inactivation, ros generation, increase in intracellular ca(2+) concentration, and upregulation of fas and fasl were found in sk-n-sh cells. sb202190 (p38mapk inhibitor) suppressed upregulation of fas and fasl. n-acetylcysteine (ros scavenger) and bapta-am (ca(2+) chelator) ...200919009558
anti-inflammatory activity of oleanolic acid by inhibition of secretory phospholipase a2.oleanolic acid, a triterpenoid known for its anti-inflammatory properties, is commonly present in several medicinal plants. the present study evaluated the effect of oleanolic acid on spla (2), a key enzyme in inflammatory reactions. oleanolic acid inhibited spla (2) activities of human synovial fluid (hsf), human pleural fluid (hpf) and vipera russelli (vrv-pl-v) and naja naja (nn-pl-i) snake venoms in a concentration-dependent manner. the ic (50) values of spla (2) from these sources ranged fr ...200919085684
catalytic activity-independent pathway is involved in phospholipase a(2)-induced apoptotic death of human leukemia u937 cells via ca(2+)-mediated p38 mapk activation and mitochondrial depolarization.in view of the controversial role of catalytic activity on the cytotoxicity of phospholipase a(2) (pla(2)), the present study is conducted to explore whether pla(2) induces apoptotic process of human leukemia u937 cells through catalytic activity-independent pathway. modification of his-48 (according to the sequence alignment with porcine pancreatic pla(2)) with p-bromophenacyl bromide (bpb) caused over 99.9% drop in enzymatic activity naja naja atra pla(2). it was found that bpb-pla(2)-induced ...200919118607
ros-mediated p38alpha mapk activation and erk inactivation responsible for upregulation of fas and fasl and autocrine fas-mediated cell death in taiwan cobra phospholipase a(2)-treated u937 cells.the aim of the present study is to explore the signaling pathway associated with naja naja atra phospholipase a(2) (pla(2))-induced apoptotic death of human leukemia u937 cells. degradation of procaspases, production of tbid, loss of mitochondrial membrane potential, and cytochrome c release were observed in pla(2)-treated cells. pla(2) treatment increased fas and fasl protein expression, and upregulated transcription of fas and fasl mrna. upon exposure to pla(2), ros generation, p38 mapk activa ...200919180563
the crystal structure of cobra venom factor, a cofactor for c3- and c5-convertase cvfbb.cobra venom factor (cvf) is a functional analog of human complement component c3b, the active fragment of c3. similar to c3b, in human and mammalian serum, cvf binds factor b, which is then cleaved by factor d, giving rise to the cvfbb complex that targets the same scissile bond in c3 as the authentic complement convertases c4bc2a and c3bbb. unlike the latter, cvfbb is a stable complex and an efficient c5 convertase. we solved the crystal structure of cvf, isolated from naja naja kouthia venom, ...200919368894
molecular docking studies and anti-enzymatic activities of thai mango seed kernel extract against snake venoms.the ethanolic extract from seed kernels of thai mango (mske) (mangifera indica l. cv. 'fahlun') (anacardiaceae) and its major phenolic principle (pentagalloyl glucopyranose) exhibited dose-dependent inhibitory effects on enzymatic activities of phospholipase a(2) (pla(2)), hyaluronidase and l-amino acid oxidase (laao) of calloselasma rhodostoma (cr) and naja naja kaouthia (nk)venoms by in vitro tests. the anti-hemorrhagic and anti-dermonecrotic activities of mske against both venoms were clearly ...200919384272
effects of cardiotoxin iii on nf-kappab function, proliferation, and apoptosis in human breast mcf-7 cancer cells.cardiotoxin iii (ctx iii), a basic polypeptide with 60 amino acid residues isolated from naja naja atra venom, has been reported to have anticancer activity. ctx iii-induced apoptosis in human breast mcf-7 cancer cells was confirmed by sub-g1 formation, phosphatidylserine (ps) externalization, and poly (adp-ribose) polymerase (parp) cleavage with an ic50 of 2 microg/ml at 48 h. effects of ctx iii on proliferation and apoptosis correlated with upregulation of bax, and downregulation of bcl-xl, bc ...200919408576
peripheral and spinal antihyperalgesic activity of najanalgesin isolated from naja naja atra in a rat experimental model of neuropathic pain.snake venoms are a rich source of various compounds that have applications in medicine and biochemistry. recently, it has been demonstrated that najanalgesin isolated from the venom of naja naja atra exerts analgesic effects on acute pain in mice. the objective of this study was to evaluate the antinociceptive effect of najanalgesin in a rat model of neuropathic pain, induced by l5 spinal nerve ligation and transaction. we observed that intraperitoneal (i.p.) administration of najanalgesin produ ...200919442704
purification and characterization of a myotoxic phospholipase a2 from indian cobra (naja naja naja) venom.a major phospholipase a2 (nn-xiii-pla2) which constitutes 20% of the whole naja naja naja venom was purified to homogeneity on cm-sephadex c-25 column chromatography. nn-xiii-pla2 is a basic protein with a mol. wt of 11,200 by sds-page. this enzyme has low enzymatic activity but is more toxic to mice than the whole venom. the ld50 value (i.p.) of nn-xiii-pla2 is 2.4 mg/kg body weight (whole venoms ld50 is 2.8 mg/kg body weight). it induces neurotoxic-like signs in experimental animals. it induce ...20092781585
anti-necrosis potential of polyphenols against snake venoms.polyphenols from the extracts of areca catechu l. and quercus infectoria oliv. inhibited phospholipase a(2), proteases, hyaluronidase and l-amino acid oxidase of naja naja kaouthia lesson (nk) and calloselasma rhodostoma kuhl (cr) venoms by in vitro tests. both extracts inhibited the hemorrhagic activity of cr venom and the dermonecrotic activity of nk venom by in vivo tests. the inhibitory activity of plant polyphenols against local tissue necrosis induced by snake venoms may be caused by inhib ...200919874222
jnk1/c-jun and p38 alpha mapk/atf-2 pathways are responsible for upregulation of fas/fasl in human chronic myeloid leukemia k562 cells upon exposure to taiwan cobra phospholipase a2.fas and fasl expression upregulation was found in human leukemia k562 cells upon exposure to naja naja atra phospholipase a(2) (pla(2)). pla(2) treatment induced an increase in intracellular ca(2+) ([ca(2+)]i) and ros generation levels, leading to activation of p38 mapk and jnk. suppression of both p38 mapk and jnk abrogated fas and fasl upregulation. unlike pla(2), catalytically inactive pla(2) treatment did not markedly increase fas and fasl protein expression, and p38 mapk activation was excl ...200919670268
membrane-bound conformation and phospholipid components modulate membrane-damaging activity of taiwan cobra cardiotoxins.membrane-damaging activity of naja naja atra cardiotoxin 3 (ctx3) on 1-palmitoyl-2-oleoyl-phosphatidylcholine (popc)/1,2-dimyristoyl-phosphatidic acid (dmpa) vesicles was approximately 3-fold that of n. naja atra cardiotoxin 4 (ctx4), while ctx3 and ctx4 displayed insignificantly permeabilizing activity in 1,2-dipalmitoyl-phosphatidylcholine (dppc)/dmpa vesicles. phospholipid-binding capability and oligomeric assembly upon binding with lipid vesicles did not closely correlate with membrane-damag ...200919673097
vanillic acid as a novel specific inhibitor of snake venom 5'-nucleotidase: a pharmacological tool in evaluating the role of the enzyme in snake envenomation.vanillic acid has been investigated for its inhibitory effect on naja naja, daboia russellii, and trimeresurus malabaricus venom 5'-nucleotidase activity. trimeresurus malabaricus venom 5'-nucleotidase activity was 1.3- and 8.0-fold higher than that of n. naja and d. russellii venoms, respectively. substrate specificity studies showed that for all the venoms tested, 5'-amp was the preferred substrate for 5'-nucleotidase. this indicates the central role of adenosine in snake envenomation. vanilli ...200919961411
syndromic approach to treatment of snake bite in sri lanka based on results of a prospective national hospital-based survey of patients envenomed by identified snakes.of 860 snakes brought to 10 hospitals in sri lanka with the patients they had bitten, 762 (89%) were venomous. russell's vipers (daboia russelii) and hump-nosed pit vipers (hypnale hypnale) were the most numerous and h. hypnale was the most widely distributed. fifty-one (6%) were misidentified by hospital staff, causing inappropriate antivenom treatment of 13 patients. distinctive clinical syndromes were identified to aid species diagnosis in most cases of snake bite in sri lanka where the bitin ...200919815895
evidence for existence of venom 5' nucleotidase in multiple forms through inhibition of concanavalin a.pharmacologically active 5' nucleotidase is a ubiquitously distributed enzyme in snake venoms. in this study the effect of concanavalin a (con-a) on different snake venoms 5' nucleotidase activity is tested in order to know the protein nature which will ultimately help in purification of the enzyme with high yield. con-a inhibited naja naja, naja kauthia, naja melanoleuca, naja naja sputatrix, agistrodon halys blomhoffii, bothrops asper and oxyranus scutellas venom 5' nucleotidase activity at di ...201020941753
molecular diversity in venom proteins of the russell's viper (daboia russellii russellii) and the indian cobra (naja naja) in sri lanka.to examine the molecular diversity of the venom proteins of the russell's viper (daboia russellii russellii) and the indian cobra (naja naja) in sri lanka, we isolated 38 venom proteins through a combination of anion exchange chromatography followed by reversed-phase high performance liquid chromatography. from the venom of d. r. russellii we isolated 15 proteins: 5 isozymes of phospholipase a(2) (pla(2)), 4 serine proteases, 2 c-type lectin-like proteins, 2 l-amino acid oxidases, 1 cysteine-ric ...201020203422
inhibitory effect of tea polyphenols on local tissue damage induced by snake venoms.the methanolic extract of fresh tea leaves of camellia sinensis l. (theaceae) (cs) was assayed for its potential to inhibit enzymes with hydrolytic activity in naja naja kaouthia lesson (elapidae) and calloselasma rhodostoma kuhl (viperidae) venoms. these snake venom enzymes are responsible for the early effects of envenomation, such as local tissue damage and inflammation. the cs extract inhibited phospholipase a(2), proteases, hyaluronidase and l-amino acid oxidase in both venoms by in vitro n ...201019585481
taiwan cobra phospholipase a2-elicited jnk activation is responsible for autocrine fas-mediated cell death and modulating bcl-2 and bax protein expression in human leukemia k562 cells.phospholipase a(2) (pla(2)) from naja naja atra venom induced apoptotic death of human leukemia k562 cells. degradation of procaspases, production of tbid, loss of mitochondrial membrane potential, bcl-2 degradation, mitochondrial translocation of bax, and cytochrome c release were observed in pla(2)-treated cells. moreover, pla(2) treatment increased fas and fasl protein expression. upon exposure to pla(2), activation of p38 mapk (mitogen-activated protein kinase) and jnk (c-jun nh(2)-terminal ...201019937732
down-regulation of the jak2/pi3k-mediated signaling activation is involved in taiwan cobra cardiotoxin iii-induced apoptosis of human breast mda-mb-231 cancer cells.cardiotoxin iii (ctx iii), a basic polypeptide with 60 amino acid residues isolated from naja naja atra venom, has been reported to have anticancer activity. exposure of mda-mb-231 cells with 0.03, 0.09, and 0.15 microm of ctx iii for 18 h, ctx iii-induced cell apoptosis, as evidenced by accumulation of sub-g1 population, externalization of phosphatidylserine, loss of mitochondrial membrane potential (deltapsim) with subsequent release of cytochrome c, and activation of both capases-9 and caspas ...201020144642
genistein, a potent inhibitor of secretory phospholipase a2: a new insight in down regulation of inflammation.some of the legumes, spices and medicinal herbs rich in genistein are known for their anti-inflammatory properties. anti-inflammatory property of these herbs is determined by subjecting secretory phospholipase a(2) (spla(2)) inhibition, a key enzyme in the inflammatory reactions by genistein.201019894024
taiwan cobra cardiotoxin iii inhibits src kinase leading to apoptosis and cell cycle arrest of oral squamous cell carcinoma ca9-22 cells.cardiotoxin iii (ctx iii), a basic polypeptide with 60-amino acid residues isolated from naja naja atra venom, has been reported to have cytotoxic activity. ctx iii exerted cytotoxicity with the s-phase cell cycle arrest, correlated with a marked decrease in the expression levels of cyclin a, cyclin b, and cyclin-dependent kinase 1 (cdk1), and apoptosis, accompanied with bax and bad up-regulation, and the down-regulation of bcl-2, p-bad, and x-linked inhibitor of apoptosis (xiap) with cytochrome ...201020493203
concomitant inactivation of the epidermal growth factor receptor, phosphatidylinositol 3-kinase/akt and janus tyrosine kinase 2/signal transducer and activator of transcription 3 signalling pathways in cardiotoxin iii-treated a549 cells.1. cardiotoxin (ctx) iii, a basic polypeptide with 60 amino acid residues isolated from naja naja atra venom, has potential anticancer therapeutic activity. the aim of the present study was to investigate the apoptotic effect (and the underlying mechanism of action) of ctx iii in human adenocarcinoma a549 cells. 2. it was found that ctx iii induces apoptosis in a549 cells, as indicated by an increase in the sub-g(1) population, phosphatidylserine externalization, loss of mitochondrial membrane p ...201020456425
prostatic involution after intraprostatic injection of cobra toxin.we evaluated the comparative effects of intraprostatic injection of cobra cardiotoxin d and botulinum toxin type a on prostate structure in the rat model.201020850839
anti-coagulant activity of a metalloprotease: further characterization from the indian cobra (naja naja) venom.a high molecular mass, non toxic metalloprotease the nn-pf3 with the bound ca(2+) and zn(2+) from the naja naja venom has been studied further for its anticoagulant property. the molecular mass by maldi-tof mass spectrometry was 67.81 kda. the nn-pf3 exhibited fibrin(ogen)olytic activity. in addition to fibrinogen, nn-pf3 hydrolyzed blood and plasma clot with the later hydrolyzed about one fold higher. the alpha polymer of fibrin was preferentially hydrolyzed over the alpha chain but the beta ch ...201019629641
chemical modification of ascorbic acid and evaluation of its lipophilic derivatives as inhibitors of secretory phospholipase a(2) with anti-inflammatory activity.the halo 6-fatty acid esters of l-ascorbic acid 3a, 3b and 6-fatty acid esters of l-ascorbic acid 5a-g were achieved from l-ascorbic acid 1. compounds 3a, 3b and 5a-g were evaluated for anti-oxidant, anti-lipid peroxidation, and secretory phospholipase a(2) (spla(2)) inhibition in vitro, and spla(2) induced mouse paw edema. all the derivatives retained their anti-oxidant property compared to ascorbic acid at 6 × 10(-4)m and are good inhibitors of lipid peroxidation at 1 mg ml(-1) as evaluated by ...201020730622
the metalloprotease, nn-pf3 from naja naja venom inhibits platelet aggregation primarily by affecting α2β1 integrin.nn-pf3 is a non-toxic, anticoagulant, high-molecular-mass (67.81 kda) metalloprotease from indian cobra (naja naja) venom. in the present study, nn-pf3 was investigated for the mechanism of inhibition of collagen-induced aggregation of human platelets. the complete inhibition of collagen-induced aggregation and partial inhibition of adp- and epinephrine-induced aggregation has the respective ic(50) of 75 ± 5, 185 ± 10, and 232 ± 12 nm, whereas no inhibition of thrombin-, arachidonic acid-, and r ...201020957364
preparation and characterization of immunoglobulin yolk against the venom of naja naja atra.chinese cobra (naja naja atra) bite is one of the leading causes of snake-bite mortality in china. the traditional anti-cobra venom serum therapy was found to be expensive and with high frequency of side effects. therefore attempts were made to generate a high titer immunoglobulin from egg yolk (igy) of crude cobra-venom immunized leghorn hens, and to standardize an effective method for producing avian antivenom in relatively pure form. the igy was isolated first by water dilution method to remo ...201021341535
evaluation of venom extracts from the cobra snakes (naja naja) of three different weights and size groups. 20103100829
systemic pathological effects induced by cobra (naja naja) venom from geographically distinct origins of indian peninsula.indian cobra (naja naja) venom from different geographical locations varied in its composition and biochemical, pharmacological and immunological properties. recently it has been shown that the variation in composition of venom from different geographical origin of indian peninsula is due to the quantitative difference in the same components and also the presence of different biochemical entities with respect to their origin. this disparity in venom composition may be due to several environmenta ...201019733040
severe infection of wild-caught snakes with spirometra erinaceieuropaei from food markets in guangzhou, china involves a risk for zoonotic sparganosis.wild-caught snakes are a popular and traditional food in china. however, little known to the public, snakes are also intermediate hosts of spirometra erinaceieuropaei, a food- and water-borne pathogen of sparganosis. therefore, we investigated the prevalence of s. erinaceieuropaei in 10 popular species of wild-caught snakes in guangzhou city (guangdong province) between july 2009 and july 2010. one hundred and twenty-four specimens of 10 species (including enhydris plumbea, zoacys dhumnades, ela ...201021348631
lipid domain formation modulates activities of snake venom phospholipase a(2) enzymes.the goal of the present study is to elucidate the effect of lipid domain formation on activities of naja naja atra and bungarus multicinctus phospholipase a(2) (pla(2)) enzymes. sphingomyelin inhibited enzymatic activity and membrane-damaging activity of pla(2) against egg yolk phosphatidylcholine (eypc), while cholesterol and cholesterol sulfate abrogated the inhibitory effect of sphingomyelin. the ability of cholesterol and cholesterol sulfate to abolish the inhibitory effect of sphingomyelin ...201020705082
interaction of naja naja atra cardiotoxin 3 with h-trisaccharide modulates its hemolytic activity and membrane-damaging activity.to address whether saccharide moieties of blood groups a, b and o antigens modulate hemolytic activity of naja naja atra cardiotoxins (ctxs), the present study was carried out. unlike other ctx isotoxins, hemolytic activity of ctx3 toward blood group o cholesterol-depleted red blood cells (rbcs) was notably lower than that of blood groups a and b cholesterol-depleted rbcs. conversion of blood group b rbcs into blood group o rbcs by alpha-galactosidase treatment attenuated the susceptibility for ...201020193704
preparation of chitosan nanoparticles containing naja naja oxiana snake venom.hydrophilic nanoparticles have received much attention for delivery of therapeutic peptides, proteins, and antigens. chitosan (cs) is a biodegradable and nontoxic polysaccharide, as a carrier for drug delivery. the study purpose was to evaluate the influence of a number of factors on the encapsulation of naja naja oxiana (indian or speckled cobra) venom and loading capacity, as well as to investigate the physicochemical structure of nanoparticles. cs nanoparticles were produced based on the ioni ...201019616121
acquired factor viii deficiency after consuming the dried gallbladder of a cobra, naja naja.acquired factor viii deficiency is very rare, often fatal. it is associated with pregnancy, autoimmune diseases, malignancy, and drugs, although no underlying cause is found in 50%. a 49-year-old male was referred with right shoulder bruising. the coagulation test showed a prolonged activated partial thromboplastin time. the factor viii level was less than 1%, and the factor viii inhibitor antibody titer was 246 bethesda units/ml. the findings were compatible with acquired factor viii deficiency ...201021120211
protective effects of hypothalamic proline-rich peptide and cobra venom naja naja oxiana on dynamics of vestibular compensation following unilateral labyrinthectomy.we tested the action of proline-rich peptide (prp-1) and cobra venom naja naja oxiana (nox) on deiters' nucleus neurons at 3rd, 15th and 35th days after unilateral labyrinthectomy (ul). early and late tetanic, post-tetanic potentiation and depression of deiters'neurons to bilateral high frequency stimulation of hypothalamic supraoptic and paraventricualar nuclei was studied. the analysis of spike activity was carried out by mean of on-line selection and special program. the complex averaged peri ...201020703940
molecular identification of three indian snake species using simple pcr-rflp method.three endangered indian snake species, python molurus, naja naja, and xenochrophis piscator are known to be significantly involved in illegal trade. effective authentication of species is required to curb this illegal trade. in the absence of morphological features, molecular identification techniques hold promise to address the issue of species identification. we present an effective pcr-restriction fragment length polymorphism method for easy identification of the three endangered snake specie ...201020384921
nonantibiotic properties of tetracyclines: structural basis for inhibition of secretory phospholipase a2.secretory phospholipase a(2) is involved in inflammatory processes and was previously shown to be inhibited by lipophilic tetracyclines such as minocycline (minotc) and doxycycline. lipophilic tetracyclines might be a new lead compound for the design of specific inhibitors of secretory phospholipase a(2), which play a crucial role in inflammatory processes. our x-ray crystal structure analysis at 1.65 a resolution of the minotc complex of phospholipase a(2) (pla(2)) of the indian cobra (naja naj ...201020211188
antihaemorrhagic potentials of fagonia cretica against naja naja karachiensis (black pakistan cobra) venom.plants have been extensively used as a remedy for the treatment of snake bites. the aim of this study was to determine the antivenom potentials of methanolic extract from the aerial parts (leaves and twigs) of fagonia cretica l. on a haemorrhage induced by venom from naja naja karachiensis. the haemorrhagic response of venom was dose dependent from 0.1 to 4.0 µg per 1.5 µl phosphate buffer saline (pbs) on vitelline veins of fertilised hens' eggs in their shells. the extract effectively eliminate ...201121656416
cytotoxic and antioxidant property of a purified fraction (nn-32) of indian naja naja venom on ehrlich ascites carcinoma in balb/c mice.a cytotoxic and antioxidant protein (nn-32) from the indian spectacled cobra naja naja venom was identified and its probable mode of action on murine ehrlich ascites carcinoma (eac) was established. the venom purified through ion exchange chromatography produced several peaks, among which fraction 32 produced cytotoxic-cardiotoxic properties. this fraction (nn-32) showed a single peak (retention time 38.3 min) by hplc using c4 column. the molecular mass determined by maldi-ms, found to be 6.7 kd ...201121530568
[influence of najanalgesin from naja naja on glt-1 in spinal cord of rat in neuropathic pain].to investigate the influence of najanalgesin on glutamate-glial transporter 1(glt-1) in spinal cord of rats after l5 spinal nerve ligation and transection (snl), and explore the spinal analgesic mechanism of najanalgesin.201121761732
membrane-damaging activity of taiwan cobra cardiotoxin 3 is responsible for its bactericidal activity.this study investigates the causal relationship between membrane-damaging activity and bactericidal activity of naja naja atra (taiwan cobra) cardiotoxin 3 (ctx3). ctx3 showed greater inhibitory activity for the growth of staphylococcus aureus (gram-positive bacteria) relative to that of escherichia coli (gram-negative bacteria). the ctx3 antibacterial activity is positively correlated with the increase in membrane permeability of bacterial cells. morphological examination showed that ctx3 disru ...201121575651
tick infestation on wild snakes in northern part of western ghats of india.in total, 167 individuals of 30 species of snakes belonging to 22 genera and five families were examined for tick infestation from november 2008 to march 2010. only two species of snakes, ptyas mucosa (l., 1758) (indian rat snake) and naja naja (l., 1758) (spectacled cobra), were found infested by ticks. all ticks collected were identified to be amblyomma gervaisi [previously aponomma gervaisi (lucas, 1847) 1. the average prevalence of these ticks on indian rat snakes (n=48) was 29.16%, with abu ...201121661308
[studies of complex lipids. synthesis of ionophore derivatives of diphosphatidylglycerol (cardiolipin)].synthesis of cardiolipin analogues containing an ionophore residue in the fatty acid moiety is described. the ionophore, dibenzo-18-crown-6, has been incorporated into second position of the glycerol residue by acylating mono- and dilysocardiolipin with a modified fatty acid anhydride. lyso-derivatives of cardiolipin have been prepared by enzymatic hydrolysis of beef heart cardiolipin by snake venom phospholipase a2 (naja naja oxiana).20113219123
scanning electron microscope study of a snake tick, amblyomma gervaisi (acari: ixodidae).the scanning electron microscope (sem) studies on both male and female tick, amblyomma gervaisi (lucas 1847) inhabiting the snake naja naja were made. detail of the surface structures as seen under sem exhibit sexual dimorphism and were compared with other tick species as reported. sem observations show characteristic alloscutal ornamentation, inornate festoons, triangular licking organ, size of the hypostome, round haller's organ, genital plate oval in male and slit-like in female, and prominen ...201224082536
Effect of membrane toxin 12 isolated from Naja naja atra on proliferation and invasion of human bladder cancer EJ cells.We investigated the effect of membrane toxin 12 (MT-12), isolated from Naja naja atra, a species of Chinese Cobra, on the proliferation and invasion of human bladder cancer EJ cells and studied its mechanisms using MTT assay, Transwell chamber invasion assay, scanning electron microscopy and flow cytometry. The results indicated that MT-12 inhibited the proliferation of bladder cancer cells in a dose-dependent manner. The half maximal inhibitory concentration (IC50) after 72 h was 0.66 µg/ml. Th ...201221993582
probing the role of substrate conformation in phospholipase a2 action on aggregated phospholipids using constrained phosphatidylcholine analogues.phospholipase a2s hydrolyze aggregated phospholipid substrates much more rapidly than dispersed monomeric ones. whether this is a consequence of interface-associated conformational changes of the enzyme or of the substrate, or of both, remains a key question in lipid enzymology. this problem is addressed herein using a rationally designed probe of substrate conformation. (1,3/2)-1-o-(phosphorylcholine)-2,3-o-dihexanoylcyclopentane-1,2,3 -triol is a novel short chain phosphatidylcholine analogue ...20123417646
naja naja atra and naja nigricollis cardiotoxins induce fusion of escherichia coli and staphylococcus aureus membrane-mimicking liposomes.our previous studies showed that the bactericidal effect of naja naja atra cardiotoxin 3 (ctx3) and naja nigricollis toxin γ was associated with their membrane-damaging activity. to elucidate the mechanism responsible for ctx3- and toxin γ-induced membrane permeability, we investigated the interacted mode of ctx3 and toxin γ with model membrane of escherichia coli (phosphatidylethanolamine (pe)/phosphatidylglycerol (pg), mol/mol, 75/25) and staphylococcus aureus (pg/cardiolipin, mol/mol, 60/40) ...201222569319
inhibition of neurotoxic secretory phospholipases a(2) enzymatic, edematogenic, and myotoxic activities by harpalycin 2, an isoflavone isolated from harpalyce brasiliana benth.secretory phospholipases a(2) (spla(2)) exert proinflammatory actions through lipid mediators. these enzymes have been found to be elevated in many inflammatory disorders such as rheumatoid arthritis, sepsis, and atherosclerosis. the aim of this study was to evaluate the effect of harpalycin 2 (har2), an isoflavone isolated from harpalyce brasiliana benth., in the enzymatic, edematogenic, and myotoxic activities of spla(2) from bothrops pirajai, crotalus durissus terrificus, apis mellifera, and ...201222899963
molecular cloning and characterization of a complement-depleting factor from king cobra, ophiophagus hannah.cobra venom factor (cvf) is an anti-complement factor existing in cobra venom. cvf proteins have been purified from the venoms of naja haje, naja siamensis, naja atra, naja kaouthia, naja naja, naja melanoleuca and austrelaps superbus, but only three full-length cdna sequences of cvf are available. in the present work, a cobra venom factor termed ovf was purified from the crude venom of ophiophagus hannah by successive gel filtration, ion-exchange and heparin affinity chromatography steps. the p ...201222561424
hemostatic interference of indian king cobra (ophiophagus hannah) venom. comparison with three other snake venoms of the subcontinent.unlike naja naja, bungarus caeruleus, echis carinatus, and daboia/vipera russellii venoms, ophiophagus hannah venom is medically ignored in the indian subcontinent. being the biggest poisonous snake, o. hannah has been presumed to inject several lethal doses of venom in a single bite. lack of therapeutic antivenom to o. hannah bite in india makes any attempt to save the victim a difficult exercise. this study was initiated to compare o. hannah venom with the above said venoms for possible interf ...201222817464
improved method for the isolation, characterization and examination of neuromuscular and toxic properties of selected polypeptide fractions from the crude venom of the taiwan cobra naja naja atra.an improved chromatographic method was developed to isolate and purify polypeptides and proteins from the crude venom of the taiwan cobra naja naja atra. the procedure devised is simple, easy to reproduce, and enables large scale isolation of almost all polypeptides and proteins in this cobra venom. six pure polypeptide fractions of the venom were isolated and characterized using gel filtration on sephadex g50 (medium), ion exchange chromatography on sp-sephadex c25, desalting on sephadex g25 (f ...201222677803
species identification from dried snake venom.illegal trade in snake parts has increased enormously. in spite of strict protection under wildlife act, a large number of snakes are being killed ruthlessly in india for venom and skin. here, an interesting case involving confiscation of crystallized dried snake venom and subsequent dna-based species identification is reported. the analysis using the universal primers for cytochrome b region of the mitochondrial dna revealed that the venom was extracted from an indian cobra (naja naja). on the ...201222268640
behavioral and morphological evidence for the involvement of glial cells in the antinociceptive effect of najanalgesin in a rat neuropathic pain model.neuropathic pain is a devastating neurological disease that seriously affects patients' quality of life. despite a high level of incidence, the underlying mechanisms of neuropathic pain are still poorly understood. however, recent evidence supports the prominent role of spinal glial cells in neuropathic pain states. in our laboratory, we observed that najanalgesin, a novel peptide isolated from the venom of naja naja atra, exerts significant analgesic effects on acute pain in mice and neuropathi ...201222687474
cardiotoxin iii suppresses mda-mb-231 cell metastasis through the inhibition of egf/egfr-mediated signaling pathway.cardiotoxin iii (ctx iii), a basic polypeptide isolated from naja naja atra venom, has been shown to exhibit anticancer activity. epidermal growth factor (egf) and its receptor, egfr, play roles in cancer metastasis in various tumors. we use egf as a metastatic inducer of mda-mb-231 cells to investigate the effect of ctx iii on cell migration. ctx iii inhibited the egf-induced activation of matrix metalloproteinase-9 (mmp-9), and further suppressed cell invasion and migration without obvious cel ...201222683533
structural and functional insights into lipid-bound nerve growth factors.nerve growth factor (ngf) is a dimeric molecule that modulates the survival, proliferation, and differentiation of nervous cells and is also known to act on cells of the immune system and endocrine system. ngfs extracted from mouse submaxillary gland and cobra venom have different immunological behaviors, yet the underlying mechanism remains unclear. here we report the crystal structure of the ngf purified from chinese cobra naja naja atra (cngf), which unexpectedly reveals a 2-tailed lipid mole ...201222649032
quercetin modulates activities of taiwan cobra phospholipase a2 via its effects on membrane structure and membrane-bound mode of phospholipase a2.the goal of the present study is to elucidate the mechanism of quercetin on modulating naja naja atra phospholipase a2 (pla2) activities. sphingomyelin inhibited pla2 enzymatic activity and membrane-damaging activity against egg yolk phosphatidylcholine (eypc), while cholesterol and quercetin abrogated the sphingomeyelin inhibitory effect. quercetin incorporation led to a reduction in pla2 enzymatic activity and membrane-damaging activity toward eypc/sphingomyelin/cholesterol vesicles. both chol ...201222581333
nanoparticle-mediated delivery of neurotoxin-ii to the brain with intranasal administration: an effective strategy to improve antinociceptive activity of neurotoxin.neurotoxin-ii (nt-ii), an analgesic peptide which was separated from the venom of naja naja atra, is endowed an exceptional specificity of action that block transmission of the nerve impulse by binding to the acetylcholine receptor in the membrane. however, it has limited permeability across the blood-brain barrier (bbb) after intravenously (i.v.) injection.201221721852
therapeutic potential of naja naja atra venom in a rat model of diabetic nephropathy.to study the protective effects of naja naja atra venom (nnav) in a rat model of diabetic nephropathy (dn).201223228832
fusogenicity of naja naja atra cardiotoxin-like basic protein on sphingomyelin vesicles containing oxidized phosphatidylcholine and cholesterol.this study investigated the effect of oxidized phosphatidylcholine (oxpc) and cholesterol (chol) on naja naja atra cardiotoxin-like basic protein (clbp)-induced fusion and leakage in sphingomyelin (sm) vesicles. compared with those on pc/sm/chol vesicles, clbp showed a lower activity to induce membrane permeability but a higher fusogenicity on oxpc/sm/chol vesicles. a reduction in inner-leaflet fusion elucidated that clbp fusogenicity was not in parallel to its membrane-leakage activity on oxpc/ ...201323426438
the protective effects of cobra venom from naja naja atra on acute and chronic nephropathy.this study investigated the effects of naja naja atra venom (nnav) on acute and chronic nephropathy in rats. rats received 6 mg/kg adriamycin (adr) once to evoke the chronic nephropathy or 8 ml/kg 50% v/v glycerol to produce acute renal failure (arf). the nnav was given orally once a day starting five days prior to adr or glycerol injection and continued to the end of experiments. the animals were placed in metabolic cages for 24 h for urine collection for urinary protein determination. the kidn ...201323983784
inhibition of src activation with cardiotoxin iii blocks migration and invasion of mda-mb-231 cells.cardiotoxin iii (ctx iii), a basic polypeptide isolated from naja naja atra venom, has been demonstrated to display anticancer activity. breast cancer is a highly malignant carcinoma and most deaths of breast cancer are caused by metastasis. in this study, we show that ctx iii blocks migration and invasion of mda-mb-231 breast cancer cells without affecting apoptosis or cell cycle arrest. ctx iii caused significant block of src kinase activity in mda-mb-231 cells. moreover, ctx iii treatment was ...201323933586
cardiotoxin iii inhibits proliferation and migration of oral cancer cells through mapk and mmp signaling.cardiotoxin iii (ctxiii), isolated from the snake venom of formosan cobra naja naja atra, has previously been found to induce apoptosis in many types of cancer. early metastasis is typical for the progression of oral cancer. to modulate the cell migration behavior of oral cancer is one of the oral cancer therapies. in this study, the possible modulating effect of ctxiii on oral cancer migration is addressed. in the example of oral squamous carcinoma ca9-22 cells, the cell viability was decreased ...201323710144
brain pharmacokinetics of neurotoxin-loaded pla nanoparticles modified with chitosan after intranasal administration in awake rats.neurotoxin (nt), an analgesic peptide which was separated from the venom of naja naja atra, is endowed an exceptional specificity of action that blocks transmission of the nerve impulse by binding to the acetylcholine receptor in the membrane. however, it has limited permeability across the blood-brain barrier (bbb).201324087853
unfolding stabilities of two paralogous proteins from naja naja naja (indian cobra) as probed by molecular dynamics simulations.structurally similar but functionally different two paralogous proteins, ctx1 (a cardiotoxin) and lntx2 (an alpha-neurotoxin), from venom of naja naja naja have been homology modeled and subjected to molecular dynamics (md) simulations at four different temperatures (298 k, 310 k, 373 k & 473 k) under close quarters of physiological conditions. each md simulation was performed for 25 ns and trajectory structures stored at every 25 ps were used to probe various structural events occurring in the ...201323791667
venom proteomic characterization and relative antivenom neutralization of two medically important pakistani elapid snakes (bungarus sindanus and naja naja).intra- and interspecific variation in venom composition has been shown to have a major effect upon the efficacy of antivenoms. due to the absence of domestically produced antivenoms, pakistan is wholly reliant upon antivenoms produced in other countries, such as india. however, the efficacy of these antivenoms in neutralising the venoms of pakistani snakes has not been ascertained. this is symptomatic of the general state of toxicological research in this country, which has a myriad of highly to ...201323714137
effect of naja naja laurenti shed skin extract on estrous cycle, hormone - cytokine profiles, histopathology of ovary and uterus of swiss albino mice.the snake shed skin though considered as biological waste products have been mentioned in folk and traditional medicine for treatment of ailments like skin disorders, parturition problems etc. shedded skin extract (5 mg.kg-1, sc) did not produce any change in the estrous cycle of normal cycling female mice. however in 10 mg.kg-1, sc dose, the extract caused a temporary cessation of the estrous cycle at diestrous phase in normal cycling female mice for 10 days. ssae (10 mg.kg-1, sc) caused a sign ...201323678544
acute acalculous cholecystitis: a rare complication of snake bite.snake bite is an environmental and occupational hazard in many tropical and subtropical countries. it demands a high level of knowledge and skill in managing the envenomation syndrome. herein, we describe a rare case of acute acalculous cholecystitis (aac) that developed in a 36-year-old man after an indian cobra (naja naja) bite in the absence of any other predisposing factors for aac. the probable mechanisms for the occurrence of aac have been highlighted. recognizing the possibility of such a ...201323473791
inhibition of leukemic u937 cell growth by induction of apoptosis, cell cycle arrest and suppression of vegf, mmp-2 and mmp-9 activities by cytotoxin protein nn-32 purified from indian spectacled cobra (naja naja) venom.a cytotoxin nn-32 (6.7 kda) from indian cobra (naja naja) venom inhibited human leukemic u937 cell growth as observed by trypan blue dye exclusion method and cytotoxicity was confirmed by mtt assay. nn-32 induced apoptosis of u937 cell and cell cycle arrest of sub-g1 phase were revealed by facs analysis. increased bax/bcl-2 ratio, increased caspase 3 and 9 activities, cleaved parp, decreased vegf, mmp-2 and mmp-9 activities were observed after nn-32 treatment of u937 cell. antileukemic activity ...201323337397
coagulopathies in naja naja karachiensis (black pakistan cobra) bites and its effect on coagulation tests upon storage of platelet-poor plasma.the aim of this study was to evaluate the effect of venom from naja naja karachiensis on platelet-poor plasma, activated partial thromboplastin time (aptt), prothrombin time (pt) / international normalized ratio (inr), thrombin time (tt) and to evaluate its effect on clotting time upon storage of plasma for a specific time period with possible mechanism responsible for that. prolongation of pt / inr, aptt and tt was observed when different concentrations of venom were introduced due to degenerat ...201323285662
anti-platelet activity of a three-finger toxin (3ftx) from indian monocled cobra (naja kaouthia) venom.a low molecular weight anti-platelet peptide (6.9 kda) has been purified from naja kaouthia venom and was named kt-6.9. maldi-tof/tof mass spectrometry analysis revealed the homology of kt-6.9 peptide sequence with many three finger toxin family members. kt-6.9 inhibited human platelet aggregation process in a dose dependent manner. it has inhibited adp, thrombin and arachidonic acid induced platelet aggregation process in dose dependent manner, but did not inhibit collagen and ristocetin induce ...201324183721
[cytotoxicity of naja naja actra venom component combined with activated immune cells on leukemia cell line kg1a].this study was aimed to investigate the cytotoxic effect of the naja naja actra venom component (nnavc) combined with activated immune cells on human acute myeloblastic leukemia line kg1a cells. the cytotoxic effects of nnavc at different concentrations on kg1a cells were measured by cck-8 method. ldh releasing assay was used to detect the cytotoxic effects of activated immune cells, nnavc combined with activated immune cells on kg1a cells and the sensitivity of kg1a treated with nnavc to activa ...201324156420
cross-reactivity against naja sumatrana (black spitting cobra) envenoming from the haffkine antivenom in a mouse model.naja sumatrana is the dominant cobra species in malaysia, singapore, borneo, and sumatra, and it does not have specific antivenom. the haffkine antivenom has been advocated instead. this study aims to determine the efficacy of this antivenom against naja sumatrana envenoming using a mouse model. methods. male swiss albino mice were used. intravenous ld50 was first determined separately for naja naja and naja sumatrana venom. ed50 was determined by preincubating antivenom with each venom at 2.5 l ...201323997967
comparison of tensilon and antivenom for the treatment of cobra-bite paralysis.we prospectively compared the ability of anti-venom and edrophonium (tensilon) to improve paralytic symptoms in 8 patients envenomed by the philippine cobra (naja naja philippinensis). twenty, 50 or 100 ml of philippine cobra antivenom were administered in a double-blind fashion by constant intravenous infusion over 30 min. even the largest dose of antivenom failed to produce marked improvement within 2 h, though enzyme-linked immunosorbent assays and neutralization tests demonstrated that it po ...20132694492
[effect of central asian cobra (naja naja oxiana) venom on the biosynthesis of nucleic acids and protein in animal cells].cobra poison at a dose of 4 microng/kg of body weight intensified the 3h-thimidine incorporation into dna of mice liver tissue; 20-40 microng/kg of the poison inhibited the incorporation. single intraperitoneal administration of high doses of cobra poison (50-150 microng/kg) decreased the incorporation of 14c-thimidine into dna 1.2-1.9-fold. little doses of the poison increased the incorporation of 14c-hydrolysate of chlorella protein into proteins of liver cells and the high doses inhibited thi ...20131027229
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