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nucleotide sequence of bacteriophage t4 gene 23 and the amino acid sequence of its product.we have determined the nucleotide sequence of gene 23 of bacteriophage t4 by the methods of maxam and gilbert and of sanger. the identities of approximately 80% of the amino acid residues of the major capsid protein which is encoded by gene 23 were determined additionally by edman degradation of the intact protein and its peptides. fifteen gene 23 amber mutation sites have been located within the sequence, and the 3' transcription termination site for genes 21, 22 and 23 has been identified.19846335532
the use of affinity chromatography to study proteins involved in bacteriophage t4 genetic recombination. 19846335687
on the role of dna replication, endonuclease vii, and rii proteins in processing of recombinational intermediates in phage t4. 19846335688
functional integrity of t, b, and natural killer cells in homosexual subjects with prodromata and in patients with aids.we have examined the numbers of the total t (t11+) cells, t-helper (t4+) cells, t-suppressor (t8+) cells, nk cells (leu7+), and the functional integrity of t, b, and nk cells in healthy male heterosexuals and compared the data to those obtained from aids patients and male homosexuals at risk. the absolute number of total t (t11+) and t-helper (t4+) cell populations were significantly reduced among most of the asymptomatic homosexual males and even more decreased in the aids patients. by contrast ...19846335953
the human t-cell circuit.recent studies have helped to rapidly advance our understanding of the human t lymphocyte, particularly with regard to the heterogeneity of t-cell subpopulations and the characterization of surface determinants on these cells that function as important membrane receptors. with the use of monoclonal antibodies, it is possible to identify cell-surface antigens which appear during t-cell ontogeny and by which functionally and phenotypically distinct subsets of t cells can be distinguished. within t ...19846336240
bacteriophage t4 gol site: sequence analysis and effects of the site on plasmid transformation.the escherichia coli lit gene product is required for the multiplication of bacteriophage t4 at temperatures below 34 degrees c. after infection of a lit mutant host, early gene product synthesis is normal, as is t4 dna replication; however, the late gene products never appear, and early gene product synthesis eventually ceases. consequently, at late times, there is no protein synthesis of any kind (w. cooley, k. sirotkin, r. green, and l. snyder, j. bacteriol. 140:83-91, 1979; w. champness and ...19846323755
gamma-t4 hybrid bacteriophage carrying the thymidine kinase gene of bacteriophage t4.among 32 lambda-t4 recombinant phages selected for growth on a thymidylate synthetase-deficient (thya) host, 2 were shown to carry the t4 thymidine kinase (tk) gene. the lambda-t4tk phages contain two t4 hindiii dna fragments (2.0 and 1.5 kilobases) that hybridize to restriction fragments of t4 dna, encompassing the tk locus at 60 kilobases on the t4 map. the t4tk insert compensates for the simultaneous host deficiencies of thymidine kinase and thymidylate synthetase in a thymidine kinase-defici ...19846323761
nuclear triiodothyronine binding sites in rat adipocytes.most effects of thyroid hormones appear to be mediated by the binding of triiodothyronine (t3) to nuclear triiodothyronine binding sites (nt3bs). although thyroid hormones influence adipocyte metabolism, nt3bs have not been described in mature adipocytes yet. this report describes t3 nuclear binding in isolated nuclei from rat epididymal fat pad adipocytes. nuclei were isolated by exposing collagenase-dispersed adipocytes to stm (sucrose, 0.25 mol/l; tris, 20 mmol/l; mgcl2, 1.1 mmol/l, ph 7.85) ...19846323915
[kinetic characteristics of the atp-pyrophosphate isotope exchange catalyzed by rna ligase from t4 bacteriophage].the dependence of initial rate v0 of atp--ppi exchange reaction catalyzed by rna-ligase of bacteriophage t4 on the concentration of atp(s), pyrophosphate (z) and mgcl2 has been determined. the dependence of v0 on s and z described by the equation v0 = k-1k2e0/(k-1 + k2) (1 + k1/s + k2/z) has been obtained for the reaction of e + s in equilibrium es in equilibrium e1 + z, where e--enzyme, e1--adenylylenzyme, s--atp, z--pyrophosphate, k1 and k2--constants of equilibrium, k-1, k2--velocity constant ...19846323974
plasmids containing multiple copies of cloned dna for use as dna size markers for gel electrophoresis, constructed by bacteriophage t4 transduction. 19846324261
[blood glucose, acth, cortisol, t4, t3 and rt3 after cholecystectomy. comparative studies of continuous peridural anesthesia and neuroleptanalgesia].15 patients (12 women and 3 men) undergoing cholecystectomy were randomized into two groups. 8 patients were operated on under continuous thoracic epidural anaesthesia in combination with light general anaesthesia. postoperatively they were kept painfree by continuous infusion of an 0.125% solution of bupivacaine via epidural catheter at a rate of 0.25-0.3 ml/kg x h over a period of four days. the 7 patients in the control group were operated on under neuroleptanalgesia. piritramide was given fo ...19846324295
antibodies reactive with human t-lymphotropic retroviruses (htlv-iii) in the serum of patients with aids.in cats, infection with t-lymphotropic retroviruses can cause t-cell proliferation and leukemia or t-cell depletion and immunosuppression. in humans, some highly t4 tropic retroviruses called htlv-i can cause t-cell proliferation and leukemia. the subgroup htlv-ii also induces t-cell proliferation in vitro, but its role in disease is unclear. viruses of a third subgroup of human t-lymphotropic retroviruses, collectively designated htlv-iii, have been isolated from cultured cells of 48 patients w ...19846324345
specificity of a cytochemical bioassay for arginine-vasopressin and its validation for plasma measurement.the total na+/k+ atp-ase activity of the thick ascending limb of the loop of henle may be stimulated by arginine-vasopressin (avp). lysine-vasopressin (lvp), oxytocin (ot), and arginine-vasotocin (avt) produce less than 5% of the enzyme activity induced by the same concentration of avp. physiological concentrations of a mixture of other hormones with known activity on the kidney (t3, t4, aldosterone, angiotensin ii, and ot) did not significantly increase total na+/k+ atp-ase activity. specific a ...19846324921
predominance of alpha 2-adrenoceptors in porcine thyroid: biochemical and pharmacological correlations.alpha-adrenergic agonists such as norepinephrine and clonidine, but not methoxamine, inhibited the increase in camp accumulation elicited by tsh in porcine thyroid slices. the inhibitory effect of norepinephrine was abolished by yohimbine but not by prazosin. likewise, the in vitro release of t4 from the pig thyroid slice stimulated by tsh was inhibited by norepinephrine and the inhibition was antagonized by yohimbine but not by prazosin. these results suggest that the inhibitory effect of alpha ...19846325127
nuclear receptors for l-triiodothyronine in quail liver.binding studies were conducted using in vitro-labeled quail liver nuclei to identify and characterize receptors for l-triiodothyronine (t3). saturation binding experiments were analyzed by scatchard analysis and indicated a single class of high-affinity, limited-capacity t3 binding sites. these receptors exhibited binding specificity as demonstrated by competition experiments between labeled t3 and unlabeled thyroid hormones or hormone analogs. binding specificity was virtually identical in quai ...19846325294
site-specific recognition of bacteriophage t4 dna by t4 type ii dna topoisomerase and escherichia coli dna gyrase.the site specificity of bacteriophage t4-induced type ii dna topoisomerase action on double-stranded dna has been explored by studying the sites where dna cleavages are induced by the enzyme. oxolinic acid addition increases the frequency at which phi x174 duplex dna is cut by the enzyme by about 100-fold, to the point where nearly every topoisomerase molecule causes a double-stranded dna cleavage event. the effect of oxolinic acid on the enzyme is very similar to its effect on another type ii d ...19846325431
recognition of single-stranded dna by the bacteriophage t4-induced type ii topoisomerase.the bacteriophage t4-induced type ii dna topoisomerase has been shown previously to make a reversible double strand break in dna double helices. in addition, this enzyme is shown here to bind tightly and to cleave single-stranded dna molecules. the evidence that the single-stranded dna cleavage activity is intrinsic to the topoisomerase includes: 1) protein linkage to the 5' ends of the newly cleaved dna; 2) coelution of essentially homogeneous topoisomerase and the dna cleavage activity; 3) inh ...19846325432
thyroid hormone secretion is more sensitive than thyroid cyclic amp accumulation to stimulation with lats in mice in vitro and in vivo.the effects of lats-immunoglobulin g (igg) on thyroid hormone secretion and on thyroid camp concentrations were investigated in mice and compared to those of tsh. in the in vitro experiments, thyroid lobes were incubated in krebs-ringer bicarbonate buffer with lats-igg or tsh for 3 h or 2 h and t3 concentrations in buffer and thyroid camp were measured by ria. t3 in the buffer was increased with 1.5 mg/ml of lats-igg (a) or 2.5 mg/ml of lats-igg (b) (1000%/5 mg or 400%/5 mg in the mckenzie bioas ...19846325527
dual parameter flow cytometric analysis of dna content, activation antigen expression, and t cell subset proliferation in the human mixed lymphocyte reaction.this study provides direct correlation via dual parameter flow cytometry (simultaneous assessment of immunofluorescence and dna content) between mixed lymphocyte reaction (mlr) responder cell entry into the s/g2/m phases of the cell cycle with the kinetics of expression of two activation-associated cell surface proteins, tac (il 2 receptor) and 4f2 (unknown metabolic function). a small population of activated cells was identifiable by expression of both tac and 4f2 antigens before peak dna synth ...19846325537
thyroid hormone inhibits purified taste bud membrane adenosine 3',5'-monophosphate phosphodiesterase activity.thyroid hormone inhibited purified taste bud membrane adenosine 3'5'-monophosphate (camp) phosphodiesterase (pde) activity in a dose-dependent manner. taste bud membrane camp pde was inhibited most effectively by thyroxine (t4) followed in order by triiodothyionine (t3), diiodotyrosine (dit) and monoiodotyrosine (mit). concentrations required for 50% inhibition (ic50) of enzyme activity were about 1 x 10(-6), 1 x 10(-5), 6 x 10(-4) m and greater than 1 x 10(-3) m for t4, t3, dit and mit, respect ...19846326212
short-term effect of morphine on the thyroid gland in male rats.experiments were designed to demonstrate that morphine may exert a direct short-term effect on the hormone release of the thyroid gland. groups of male rats were injected with single doses of 1, 5 and 10 mg/kg morphine, or with 2 mg/kg naloxone and in addition with morphine 30 min after naloxone and/or with naloxone 30 min after morphine pre-treatment. the rats were killed by decapitation 15, 30 and 60 min after the injection and serum was collected and stored for subsequent tsh, t4 and t3 radio ...19846326448
comparison of gallium-67 scanning, bronchoalveolar lavage, and serum angiotensin-converting enzyme levels in pulmonary sarcoidosis. predicting response to therapy.patients with active pulmonary sarcoidosis underwent bronchoalveolar lavage, gallium scan, and serum angiotensin-converting enzyme (ace) level determination prior to treatment with corticosteroids. pulmonary function was tested before and after therapy. increase in vital capacity after treatment ranged from 40 to 1,030 ml; 12 of the 16 patients studied had an increase of more than 200 ml. there was a close correlation between the percentage uptake of gallium scan and the increase of the vital ca ...19846326626
recovery characteristics following antagonism of atracurium with neostigmine or edrophonium.the evoked reversal characteristics of atracurium were studied in 21 patients using edrophonium or neostigmine and a train-of-four pattern of stimulation. reversal of residual atracurium -induced neuromuscular blockade was significantly more rapid using edrophonium compared with neostigmine. the ratio of the fourth twitch in the train-of-four to the first twitch--the t4 ratio--was significantly greater when the first twitch (t1) had recovered to 75% of control t1, using edrophonium compared with ...19846326785
hormonal effects on liver glutamate dehydrogenase in newly weaned, prepubertal rats.glutamate dehydrogenase (gdh) was found to be inducible in 28-day-old sprague dawley rats by single injections of cortisol hemisuccinate (10 micrograms/g bw), glucagon (3 micrograms/g), (bu)2camp (100 micrograms/g), t4 (20 micrograms/g), or t3 (10 micrograms/g). similar responses were not seen in either younger or older rats. the maximum response to cortisol was seen in 2 h, and to glucagon and (bu)2camp in about 8 h. both effects were inhibited by actinomycin d and cycloheximide, and were accom ...19846327242
forskolin stimulation of thyroid secretion of t4 and t3.forskolin is a potent activator of adenylate cyclase in many tissues including the thyroid gland. we compared the effects of 10(-5) m forskolin and 100 mu units/ml tsh on the dynamics of t4 and t3 secretion from perfused dog thyroid lobes. both agents induced pronounced increases in t4 and t3 secretion. the increase in secretion was significantly steeper during forskolin than during tsh stimulation. this may suggest that early processes such as tsh-receptor interaction and the subsequent activat ...19846327383
nucleotide sequence reveals overlap between t4 phage genes encoding dihydrofolate reductase and thymidylate synthase.we have determined the nucleotide sequence of a 1075-base-pair hindiii fragment of the t4 phage genome. this fragment contains the structural gene (frd) for dihydrofolate reductase and part of the gene (td) encoding thymidylate synthase. the fragment contains a 579-base-pair open reading frame, encoding a 193-residue polypeptide with a calculated mass of 21,603 da, in agreement with our reported subunit molecular mass of 23,000. the deduced amino acid sequence shows partial homology with other d ...19846327673
beta 2- and alpha 2-adrenergic receptors and receptor coupling to adenylate cyclase in human mononuclear leukocytes and platelets in relation to physiological variations of sex steroids.in view of evidence, largely in animals, indicating effects of sex steroids on adrenergic receptors, we measured mononuclear leukocyte (mnl) beta 2-adrenergic receptors and adenylate cyclase sensitivity to stimulation by isoproterenol as well as platelet alpha 2-adrenergic receptors and sensitivity of sodium fluoride-stimulated adenylate cyclase to inhibition by epinephrine in 3 groups of normal humans with physiologically disparate levels of testosterone, estradiol, and progesterone (10 normal ...19846327751
dissociation of cortisol and adrenal androgen secretion in the hypophysectomized, adrenocorticotropin-replaced chimpanzee.we tested the hypothesis that adrenal androgen production is supported by a pituitary factor distinct from acth. six adult male chimpanzees who had completed adrenal maturation (adrenarche) were castrated and either hypophysectomized or sham hypophysectomized. hypophysectomized animals received synthetic acth-(1-24) and t4 to prevent adrenal insufficiency and hypothyroidism. adrenal function was evaluated with a 3-h acth infusion before and 7, 21, 40, 120, and 180 days after hypophysectomy. plas ...19846327755
functional and phenotypic comparison of human t cell leukemia/lymphoma virus positive adult t cell leukemia with human t cell leukemia/lymphoma virus negative sézary leukemia, and their distinction using anti-tac. monoclonal antibody identifying the human receptor for t cell growth factor.adult t cell leukemia (atl) and sézary leukemia are malignant proliferations of t lymphocytes that share similar cell morphology and clinical features. atl is associated with htlv (human t cell leukemia/lymphoma virus), a unique human type c retrovirus, whereas most patients with the sézary syndrome do not have antibodies to this virus. leukemic cells of both groups were of the t3, t4-positive, t8-negative phenotype. despite the similar phenotype, htlv-negative sézary leukemic cells frequently f ...19846327770
a physical map of bacteriophage t4 including the positions of strong promoters and terminators recognized in vitro.we present a linearized physical map of the genome of bacteriophage t4. this map contains the cleavage sites for restriction enzymes smai, kpni, sali, bglii, xhoi, xbai, clai , haeii, ecori, and ecorv . it also contains about 200 taqi sites. the promoter sites recognized in vitro and a number of rho independent terminators have also been mapped.19846328215
structural organization of the 3' half of the rat thyroglobulin gene.we report the structural organization of an 80 kb segment of rat dna, which encodes for about 40% of thyroglobulin mrna at the 3' end. the codogenic information included in this segment is splitted in 17 exons of homogeneous size (about 200 bp). the seven exons at the extreme 3' end have been precisely defined by dna sequence analysis. no clear sequence homology is found among the exons, even though their coding capacity is quite similar, from 55 to 63 aminoacids residues. we located 2 hormonoge ...19846328423
intervening sequence in the thymidylate synthase gene of bacteriophage t4.the continuous sequence of 2.3 kilobases in a 3-kilobase dna fragment encoding the structural gene for coliphage t4 thymidylate synthase (5,10-methylenetetrahydrofolate:dump c-methyltransferase, ec 2.1.1.45) was determined by using the m13 dideoxy chain-termination method. from the coding information within this gene and that provided by sequence analysis of selected cnbr peptides from the protein product, the primary structure of t4 thymidylate synthase was determined. the most significant find ...19846328492
the effects of delta 9-tetrahydrocannabinol on serum thyrotropin levels in the rat.the effects of acute treatment with delta 9-tetrahydrocannabinol (delta 9-thc) on serum levels of thyrotropin (tsh) and the thyroid hormones triiodothyronine (t3) and thyroxine (t4) were determined in the rat. intraperitoneal doses of delta 9-thc greater than 3 mg/kg reduced serum tsh levels to less than 10% of control. the ed50 for delta 9-thc was approximately 0.3 mg/kg. after a 10 mg/kg dose of delta 9-thc, the maximum decrease in serum tsh occurred at one hour. both serum t3 and serum t4 lev ...19846328543
selective tropism of lymphadenopathy associated virus (lav) for helper-inducer t lymphocytes.lymphadenopathy associated virus ( lav ) has been isolated from patients with the acquired immunodeficiency syndrome (aids) or lymphadenopathy syndrome. since the immune deficiency in aids seems to be primarily related to the defect of the helper-inducer t lymphocyte subset, the possibility that lav is selectively tropic for this subset was investigated. fractionation of t lymphocytes was achieved by cellular affinity chromatography with monoclonal antibodies. in a hemophilic patient who was a h ...19846328660
adaptation of lymphadenopathy associated virus (lav) to replication in ebv-transformed b lymphoblastoid cell lines.a strain of lymphadenopathy associated retrovirus ( lav ) passaged in vitro was used to infect a lymphoblastoid cell line obtained by transformation with epstein-barr virus of b lymphocytes from a healthy donor. the virus produced from this line (b- lav ) was also able to grow at a high rate in some other lymphoblastoid lines and in a burkitt lymphoma line. this adapted strain retained the biochemical, ultrastructural, and antigenic characteristics of the original strain, as well as its tropism ...19846328661
decreased t4 to t3 conversion in tissues of streptozotocin-diabetic rats.the effect of experimental diabetes on t4 to t3 conversion, t3-deiodination, and the pituitary response to a dose of t4 and t3 was studied. pituitary gh and plasma tsh were determined as a measure of the biological response to thyroid hormones. thyroidectomized rats, 5 days after injection with saline or streptozotocin (thyroidectomized-control (th.c) and thyroidectomized-diabetic (th.d) rats, respectively) received an ip dose of t4 + [125i]t4 or t3 + [125i]t3. rats from each group were sacrific ...19846328820
role of radiation therapy in carcinoma of the hypopharynx.in a series of 199 patients with hypopharyngeal carcinoma treated with irradiation, the primary tumor was controlled in 63 per cent, 54 per cent, 44 per cent and 14 per cent of t1-t4 lesions, respectively. the five-year actuarial survival for stages i, ii, iii and iv patients was 60 per cent, 66 per cent, 49 per cent and 18 per cent. it was significantly better in patients with tumors located at the upper hypopharynx (p = 0.024). early lesions yielded satisfactory results with irradiation alone. ...19846328883
t-lymphocyte subset interactions in the cell-mediated immune response to epstein-barr virus.the t-lymphocyte subset interactions in the cell-mediated response to epstein-barr virus (ebv) were studied in an in vitro system in which the ability of t lymphocytes to inhibit outgrowth of autologous ebv-transformed b lymphocytes is assessed. inhibition could be demonstrated within lymphocytes of both the t4 and t8 surface phenotypes. outgrowth inhibition was observed more frequently when the effector t-cell population contained cells of both surface phenotypes. in blocking experiments the ok ...19846329522
regulation of thyroxine 5'-deiodinase activity by 3,5,3'-triiodothyronine in cultured rat anterior pituitary cells.the influence of the medium t3 concentration on iodothyronine 5'-deiodinase activity was studied in cultured anterior pituitary cells derived from chronically hypothyroid rats. type ii (propylthiouracil-insensitive) enzyme activity, measured with t4 as substrate, was reduced by t3 in a dose-dependent manner, with an ed50 of approximately 1.4 x 10(-10) m free t3. density gradient centrifugation was used to obtain populations of pituitary cells relatively enriched in thyrotrophs, somatotrophs, mam ...19846329656
characterization of thyroid hormone stimulation of uridine uptake by rat pituitary tumor cells.t3 caused a dose-related increase in the rate of [3h]uridine uptake into gh4c1 rat pituitary tumor cells. t3 increased uridine uptake to 130-180% of the control value, with a half-maximal effect at approximately 1 nm. t3 exerted a half-maximal effect at 1 h and a maximal effect at 2 h. in contrast, epidermal growth factor also increased uridine uptake by 75%, with an ed50 of 0.6 ng/ml (0.1 nm), but a half-maximal response required 4 min and a maximal effect required 20 min. t3 increased the rate ...19846329664
perinatal age and sex variations of the triiodothyronine nuclear receptors in the chick pectoralis major muscle.the ontogenesis of the nuclear triiodothyronine receptors was determined in the pectoralis muscle of male and female chicken at 18 days in ovo and 0, 3, 6, 14 and 35 days ex ovo. our results show the presence of putative t3 nuclear receptors with equilibrium dissociation constant values (kd approximately 5.50 x 10(-10) m) in good agreement with these reported in other tissues. the t3 receptor numbers decrease from 18 days incubation to 6-day-old animals, then increase until 35 days of age. compa ...19846329852
nih conference. acquired immunodeficiency syndrome: epidemiologic, clinical, immunologic, and therapeutic considerations.the acquired immunodeficiency syndrome is a new disease whose cause is unknown but is almost surely due to a transmissible agent, most likely a virus. the disease is clearly spread by sexual contact, particularly homosexual activity. blood-borne transmission constitutes the other major recognized form of spread of the disease, although it is highly likely that the disease is not readily spread through casual, nonsexual, non-blood-borne routes. although the disease is still highly concentrated in ...19846318629
cruciform-resolvase interactions in supercoiled dna.t4 endonuclease vii, which cleaves holliday-like junctions in dna, specifically cleaves short inverted repeats in supercoiled plasmids. these sequences are subject to site-specific cleavage by single-strand-specific nucleases, and cruciform formation has been suggested as an explanation for this observation. this proposal is greatly strengthened by the present data, since a formal analogy between cruciform structures and holliday junctions exists. resolution of a variety of unrelated cruciform s ...19846319022
cloning and physical mapping of an early region of the bacteriophage t4 genome.we have cloned dna restriction fragments from the largely nonessential region of bacteriophage t4 located between genes 39 and 56. the cloned dna fragments were used to construct a precise map of the sites in this region recognized by eight restriction endonucleases. this restriction map allowed us to compare the cytosine-containing t4 dna used for cloning with the hydroxymethylcytosine-containing dna of wild-type t4; there were no detectable rearrangements in the region tested. we were also abl ...19846319228
leydig cell hypoplasia causing male pseudohermaphroditism: diagnosis 13 years after prepubertal castration.an 11-yr-old patient with male pseudohermaphroditism who was castrated at nine days of age and raised thereafter as a female was evaluated to determine the cause of abnormal sexual differentiation. stimulation with acth for 8 h revealed no abnormality in the biosynthesis of cortisol or adrenal androgens. the administration of fluoxymesterone (10 mg, orally, daily) for 5 weeks at age 13 yr led to significant decrements in serum levels of sex steroid-binding globulin and t4-binding globulin to a d ...19846319451
characterization of guinea pig cytomegalovirus dna.the genome of guinea pig cytomegalovirus (gpcmv) was analyzed and compared with that of human cytomegalovirus (hcmv). gpcmv and hcmv dnas were isolated from virions and further purified by cscl centrifugation. purified gpcmv dna sedimented as a single peak in a neutral sucrose gradient and was infectious when transfected into guinea pig embryo fibroblast cells. the cytopathology was characteristic of that seen after infection with gpcmv. virus dna purified from virions isolated from infected gpe ...19846319742
nuclear thyroxine and 3,5,3'-triiodothyronine receptors in human mononuclear blood cells during pregnancy.serum free t4, free t3, tsh and maximal nuclear binding capacity for t4 and t3 in mononuclear blood cells were measured in 12 control women, in 12 normal pregnant women in the first and in 12 women in the third trimester. serum free t4 and t3 were decreased in late pregnancy compared to control women, serum free t4: 9.1 pmol/l(mean) vs 12.9 pmol/l(mean); serum free t3: 4.0 pmol/l(mean) vs 6.2 pmol/l(mean), without any change in tsh levels: 2.2 mu/l(mean) vs 1.8 mu/l (mean). concomitantly, the ma ...19846320566
putative nuclear triiodothyronine receptors in tadpole erythrocytes: regulation of receptor number by thyroid hormone.putative thyroid hormone (th) receptors have been detected in the nuclei of red blood cells (rbcs) from rana catesbeiana tadpoles, and their binding characteristics have been examined. nuclear t3 saturation analyses were carried out in vitro in intact rbcs suspended in phosphate-buffered amphibian ringer. after incubation with t3, intact nuclei were obtained by centrifugation after lysing the cells in a sucrose-tris-hcl buffer containing 0.2% saponin and then adding triton x-100 (final concentra ...19846321136
expression of hla-dr antigens in nasopharyngeal carcinoma: an immunohistological analysis of the tumour cells and infiltrating lymphocytes.a panel of conventional and monoclonal antibodies was used to examine the immunohistological characteristics of malignant epithelial cells and infiltrating lymphocytes in frozen sections of nasopharyngeal carcinoma (npc) biopsies from 10 tunisian patients. three main categories of cells were identified. (1) tumour cells which were positive for epstein-barr nuclear antigen, hla-abc and keratin determinants. in most samples, the tumour cells also expressed variable amounts of hla-dr antigens. the ...19846329970
general transduction in rhizobium meliloti.general transduction by phage phi m12 in rhizobium meliloti su47 and its derivatives is described. cotransduction and selection for tn5 insertions which are closely linked to specific loci were demonstrated. a derivative of su47 carrying the reca::tn5 allele of r. meliloti 102f34 could be transduced for plasmid r68.45 but not for chromosomally located alleles. phage phi m12 is morphologically similar to escherichia coli phage t4, and restriction endonuclease analysis indicated that the phage dna ...19846330024
severe combined immunodeficiency associated with absent t4+ helper cells. 19846330337
investigations on myelinogenesis in vitro: regulation of 5'-nucleotidase activity by thyroid hormone in cultures of dissociated cells from embryonic mouse brain.the developmental pattern of the myelin-associated 5'-nucleotidase and its regulation by l-3,3',5,-triiodothyronine (t3) have been demonstrated in a culture system of cells dissociated from embryonic mouse brain. hypothyroid calf serum containing low levels of t3 (31 ng/100 ml), and thyroxine, t4 (less than 1 microgram/ml), was used in the culture medium in place of normal calf serum (t3, 103 ng/100ml; t4, 5.7 micrograms/ml) to render the cultures responsive to exogenously added t3. by means of ...19846330377
diseases of the adrenal cortex of dogs and cats.of cases of hyperadrenocorticism in small animals 80-85% are the result of adrenocortical hyperplasia. middle-aged or older poodles, dachshunds, boston terriers and boxers are most commonly affected, and cats rarely. clinical signs include polydipsia, polyuria, alopecia, abdominal distension, lethargy, weakness, hepatomegaly, calcinosis cutis, testicular atrophy and anestrus. hematologic and biochemical changes may include neutrophilia, lymphopenia, monocytosis, eosinopenia, increased blood leve ...19846330521
delayed onset of infectious mononucleosis associated with acquired agammaglobulinemia and red cell aplasia.in 1974, an 11-year-old white boy with the x-linked lymphoproliferative syndrome developed hyper-igm after becoming infected with epstein-barr virus. however, he failed to develop normal immune responses against the virus. in december 1981, when red cell aplasia occurred, he was given packed erythrocytes and gammaglobulin. nine weeks later, acute infectious mononucleosis developed. concurrently, his t4/t8 helper/suppressor ratio decreased from 2.7 to 0.2, and igm antibodies to epstein-barr virus ...19846331239
ontogeny, regional distribution and properties of thyroid-hormone receptors in the developing chick brain.studies on the thyroid-hormone receptors in the nuclei of developing chick brain revealed a single class of binding sites for tri-iodothyronine (t3) and thyroxine (t4) at all embryonic and adult ages. high-affinity [ka = (1.85-3.3) x 10(9)m-1 and (0.3-0.6 x 10(9)m-1 for t3 and t4 respectively] receptors were detected in the brain as early as day 7 of embryonic development; their level increased progressively rapidly until day 13, and thereafter the value remained essentially constant during deve ...19846331419
decreased 5'-nucleotidase activity in a t lymphocyte subpopulation from patients with b cell chronic lymphocytic leukemia.the activity of the ectoenzyme 5'-nucleotidase (5'n) was determined in the t lymphocyte subpopulations from patients with chronic lymphocytic leukemia (cll). 5'n could be detected only in the t cells from patients whose b cells also had enzyme activity. the specific activity of cll t4 cells was 0.17 +/- 0.02 micron/h/mg protein, similar to that of normal t4 cells, which was 0.13 +/- 0.08 micron/h/mg. the cll t8 cells, however, had a significantly lower 5'n activity (0.17 +/- 0.02 micron/h/mg) th ...19846331548
production of t lymphocyte colony-forming units from precursors in human long-term bone marrow cultures.t cell differentiation in human marrow was studied in dexter type long-term bone marrow cultures. in these cultures, t lymphocyte colony-forming units (tl-cfu), e rosette-forming cells (e+), and t3+, t4+, and t8+ cells (assayed by indirect immunofluorescence) were found to be present for at least 7 weeks. it was investigated whether the existence of t cells in long-term culture resulted from the persistence of inoculated t lymphocytes or from the production by immature progenitors. no significan ...19846331865
sézary syndrome with hyposplenism.phenotypic, functional and clinical analysis of two patients with sezary syndrome are presented. both patients had an elevated lymphocyte count with the helper/inducer cell phenotype by analysis with monoclonal antibodies (okt3+, t4+, t6-, t8-, m1-), had the characteristic cerebriform nucleus of sezary cells, and were fc-igg receptor negative. the functional tests revealed no proliferative, cytotoxic or immunoregulatory activity of patient e.p.'s leukemic cells, while the lymphocytes of patient ...19846331867
natural killer-like activity mediated by activated t lymphocytes.diverse types of lymphocytes mediate in vitro cytotoxic activity. in addition to ctls (cytotoxic t lymphocytes) and nk (natural killer) cells which differ in their activation requirements, target specificities, and lytic mechanisms, a natural killer-like activity of activated cells (a-nk) has recently been described. the data presented here suggest that an activated t lymphocyte can mediate a-nk activity. a-nk activity can be separated from resting nk activity by its requirement for activation a ...19846331893
analysis of t cell subsets by monoclonal antibodies in patients with tuberculosis after in vitro stimulation with purified protein derivative of tuberculin.by using okt monoclonal antibodies; okt3(pan t), okt4(inducer/helper), okt8 (suppressor/cytotoxic) and okia1, t lymphocyte subsets were examined in lymphocytes of patients with tuberculosis both before and after in vitro stimulation with purified protein derivative of tuberculin (ppd). in freshly obtained lymphocytes samples before culture, a significantly high t4/t8 ratio in pleural fluid lymphocytes (pfl) from patients with tuberculous pleurisy was observed as compared with either their pbl, o ...19846331920
characterization of the response of human thymocytes and blood lymphocytes to the synergistic mitogenicity of 12-o-tetradecanoylphorbol-13-acetate (tpa)-ionomycin.the combination of the phorbol ester 12-o-tetradecanoylphorbol-13-acetate (tpa) and the calcium ionophore ionomycin is synergistically mitogenic for human fetal and infant thymocytes as well as peripheral blood lymphocytes. optimal mitogenic stimulation is achieved when tpa and ionomycin are used at doses of 0.5-1 ng/ml and 0.5-1 microgram/ml, respectively. phenotypic analysis and cell sorting show that the thymocytes responsive to the mitogen have a mature or medullary phenotype (t1+, t3+, t11+ ...19846332025
activation of human t lymphocytes ii. involvement of the t3 antigen in polyclonal t cell activation by mitogenic lectins and oxidation.the effect of monoclonal antibodies against the t cell surface antigens t3 and t4 on accessory cell-dependent mitogen-induced proliferation of human antigen-specific t4+ t lymphocyte clones and purified peripheral blood t cells was studied. to avoid the fc receptor-dependent mitogenic effects of the okt3 antibodies, monocytes were replaced by epstein-barr virus-transformed b lymphoblastoid cells as accessory cells. monoclonal antibody okt3 but not okt4 inhibited the response of both t lymphocyte ...19846332027
influence of acth on serum hormone content and its anticonvulsant action towards infantile spasms.ten patients with infantile spasms were treated with acth, which resulted in a suppression of thyroxine through an increase of the serum cortisol level and suppression of pituitary tsh secretion. the thyroxine level in the excellent-response group was suppressed more than that in the other groups. there was a statistically significant difference (t-test, p less than 0.01) in the suppression of t4 between the excellent-response group and the others. although the high cortisol level was essential ...19846321866
effects of elevated prolactin and its normalization on thyroid hormone, cardiac beta-adrenoreceptor number and beta-adrenergic responsiveness.subcutaneous inoculation of the prolactin secreting mttw15 adenoma in male wistar furth rats for 4 weeks produced a significant increase in serum prolactin and a corresponding decrease in peripheral beta-adrenergic responsiveness. both the isoproterenol induced drink and heart rate responses used to assess the beta-adrenergic responsiveness were significantly reduced in the hyperprolactinemic rat. serum t3 and t4 levels were measured as was cardiac beta-adrenergic receptor number to ascertain if ...19846321874
[isolation of highly purified rna ligase from bacteriophage t4].a technique for isolation of rna-ligase of bacteriophage t4 was proposed. it is mainly based on the using of soviet materials and sorbents and includes seven purification stages. the technique enables to isolate about 80 000 units of active enzyme from 100 g of e. coli b cells infected with the phage. t4am n82; that makes up 20% of the activity of the cell extract. the obtained preparations of rna-ligase are homogeneous by the data of electrophoresis and practically, free of endo- and exonucleas ...19846322156
[myxedema coma: myth or reality? discussion apropos of 7 recent cases].the authors, in reporting 7 personal cases, confront their findings with previously published data. the study of cases presented as myxedema comas consistently demonstrates a precipitating cause, which in itself can produce a low t3 and t4 syndrome. the occurrence of such a cause in a patient with hypothyroidism can lead to acute decompensation, but should such conditions be considered as myxedema comas since treatment is above all aimed against the acute aggression?19846322330
growth hormone and insulin-like growth factor i in german shepherd dwarf dogs.the roles of growth hormone (gh) and insulin-like growth factor i (igf i) were studied in 9 german shepherd dwarf dogs. gh deficiency was evidenced in all dogs by an absence of increase in gh levels in response to clonidine administration. while the mean igf i concentration in normal adult german shepherds was 280 +/- 23 ng/ml and 345 +/- 50 ng/ml in immature animals, the mean igf i concentration in the dwarf dogs was 11 +/- 2 ng/ml (mean +/- sem, p less than 0.001). in the affected animals, pla ...19846322493
decreased beta-adrenergic receptors in rat heart in streptozotocin-induced diabetes: role of thyroid hormones.the effect of streptozotocin-induced diabetes on the beta-adrenergic receptor-coupled adenylate cyclase was studied in rat heart particulate fractions. streptozotocin treatment decreased the number of myocardial beta-adrenergic receptors by 34% with no change in the apparent affinity of these receptors for [3h]dihydroalprenolol. the maximal isoproterenol-activated accumulation of camp in streptozotocin-treated rat hearts was decreased by only 10%. insulin administration to streptozotocin-treated ...19846323144
stimulation of thyroidal thiol endopeptidases by thyrotropin.rabbit thyroids contain cathepsin d (cd) and several thiol endopeptidases including cathepsin b and three newly described enzymes (cathepsins 180k, 110k, and 45k). the present paper assesses the relative physiological importance of these enzymes in thyroglobulin degradation in rabbits. thyroidal thiol endopeptidase [thiol thyroglobulin hydrolase (thiol tgh)] activity increased in the absence of changes in cd activity in animals treated with 10 u bovine tsh. peak enzyme activity occurred 24 h aft ...19846360667
suppression by thymidine-requiring mutants of escherichia coli k-12.thymidine-requiring strains of escherichia coli isolated by trimethoprim selection often simultaneously acquire the ability to suppress bacteriophage t4 nonsense mutations. suppression is lost in thy+ revertants and recombinants, but is sometimes retained in thya plasmid-bearing transformants. suppression is restricted in strr derivatives of the thy- mutants, indicating that suppression occurs at the level of translation.19846360992
evidence for intermediates during unfolding and refolding of a two-domain protein, phage t4 lysozyme: equilibrium and kinetic studies.equilibrium and kinetic studies of the unfolding-refolding of phage t4 lysozyme induced by guanidine hydrochloride are reported. tryptophan fluorescence and circular dichroism (cd) were used as observables. several results indicated the existence of intermediates in the unfolded-folded transition, including (1) the noncoincidence of the transition observed by fluorescence and cd, (2) the asymmetry of the transition recorded by cd, and (3) triphasic kinetics, followed by both observables, account ...19846362723
the phenotype of lymphocytes in a thymoma as studied with monoclonal antibodies.in a thymoma, with lymphocytic predominance, we characterized the lymphocytes using a battery of monoclonal antibodies. the t lymphocytes had a phenotype most characteristic of cortical thymocytes (t3+, t4+, t6+, t8+, t11+, tdt+, pna+).19846362939
incorporation of 1,n6-ethenoadenosine into the 3' terminus of trna using t4 rna ligase. 1. preparation of yeast trnaphe derivatives.the 3'-terminal a-c-c-a sequence of yeast trnaphe has been modified by replacing either adenosine 76 or 73 with the fluorescent analogues 1,n6-ethenoadenosine (epsilon a) or 2-aza-1,n6-ethenoadenosine (aza-epsilon a). t4 rna ligase was used to join the nucleoside 3',5'-bisphosphates to the 3' end of the trna which was shortened by one [trnaphe(-a)] or four [trnaphe(-acca)] nucleotides. it was found that the base-paired 3'-terminal cytidine 72 in trnaphe(-acca) is a more efficient acceptor in the ...19846363066
incorporation of 1,n6-ethenoadenosine into the 3' terminus of trna using t4 rna ligase. 2. preparation and ribosome interaction of fluorescent escherichia coli trnametf.a fluorescent derivative of trnametf from escherichia coli has been prepared which contains 1,n6-etheno-adenosine (epsilon a) in the place of adenosine 73, the fourth residue from the 3' end. the labeled trna, trnametf epsilon a73, is fully active with respect to aminoacylation, formylation and formylmethionyl transfer to puromycin. the preparation procedure entails the chemical removal of four nucleotides from the 3' end of trnametf, ligation of the truncated molecule with epsilon a 3',5'-bisph ...19846363067
genetic analysis of serum thyroxine content and audiogenic seizures in recombinant inbred and congenic strains of mice.we previously proposed that the audiogenic seizure (ags) susceptibility of 21 +/- 1-day-old dba/2 (d2) mice may result from an early postnatal elevation in serum thyroxine (t4) concentration. in the present study we used seven c57 x dba (bxd) recombinant inbred strains and the d2.b6-iasb congenic strain to study the association between serum t4 content and susceptibility to ags. the d2.b6-iasb congenic mice are genetically similar to the d2 mice except for the iasb gene, which inhibits ags susce ...19846363115
long-term alprenolol treatment affects serum t4, t3 and rt3 in euthyroid patients with ischaemic heart disease.after treatment with alprenolol for 1 year, serum 3,3',5'-triiodothyronine (rt3) was significantly increased (p less than 0.01) in a group (n = 20) of euthyroid subjects compared to a control group (n = 20) given placebo. all subjects had definite or suspected myocardial infarction one year previously. serum thyroxine (t4), free t3 index (ft4i), serum 3,5,3'-triiodothyronine, (t3) and free t3 index (ft3i) were not significantly different in the two groups. alprenolol and placebo were gradually w ...19846364669
effects of thyroid hormones on adipose tissue development in sherman and zucker rats.it has been reported that mild hyperthyroidism in the young sherman rat induces adipose tissue hyperplasia, concomitant with cell size reduction, and that hypothyroidism induces opposite effects. the present experiments were designed to study the evolution of cellularity in retroperitoneal and epididymal adipose tissue during a long term thyroxine (t4) treatment or in t4-treated rats, after the treatment had been stopped. in both cases, hyperplasia was transient with the observation that the adi ...19846364827
glucose homeostasis in fasted neonatal rats treated with high doses of l-thyroxine.a neo-t4 syndrome was induced by subcutaneous administration of high doses of l-thyroxine (t4) to neonatal rats. these doses produced important alterations in carbohydrate metabolism: hypoglycemia, hypoinsulinemia and increased levels of blood lactate, pyruvate and ketone bodies. t4-treated and control rats were subjected to fasting. in contrast to controls where glycemia decreased to 60% of basal values, in 11-day-old neo-t4 rats blood glucose levels decreased to only 90% of basal values. these ...19846365184
intra-epithelial lymphocytes in the normal epididymis. a mechanism for tolerance to sperm auto-antigens?using a monoclonal immunoperoxidase technique on frozen tissue sections of normal testis and epididymis, a distinctive distribution of lymphocytes has been identified. almost all of the intra-epithelial lymphocytes were t cells and the majority of these belonged to the t8+ ("suppressor/cytotoxic") subset. the distribution contrasted with the predominance of the t4+ ("helper/inducer") subset in the interstitial tissues and in normal peripheral blood. the predominance of the "suppressor/cytotoxic" ...19846365234
work capacity and left ventricular function during rehabilitation after myocardial revascularization surgery.a prospective randomized trial was conducted to evaluate the effects of exercise-based cardiac rehabilitation after myocardial revascularization surgery (mrs) on work capacity (measured in mets) and left ventricular function as determined from ejection fraction (lvef). twenty-eight patients undergoing mrs were randomly assigned to experimental (aerobic exercise, n = 19) or control (muscle relaxation and low-level exercise, n = 9) groups. patients were studied before surgery (t1) and 2 (t2), 8 (t ...19846365351
immunocompetent and accessory cells in dermatitis herpetiformis.monoclonal antibodies were used in conjunction with the biotin-avidin immunolectin method and the indirect immunofluorescence method to detect lymphocyte subsets in patients with dermatitis herpetiformis (dh) in 50% potassium iodide (ki)-induced skin lesions and in density-gradient-isolated peripheral blood. the proportions of t3-, t4-, and t8-positive lymphocytes in peripheral blood in patients with dh were 76 +/- 6, 48 +/- 7, and 28 +/- 4% and did not differ significantly from those in healthy ...19846365380
crystallization of the gene 45 protein from the dna replication fork of bacteriophage t4.the gene 45 protein from bacteriophage t4 has been purified and is crystallized. this protein is part of the t4 dna replication complex. the crystallized protein is active in complementation assays. x-ray diffraction analysis is in progress; data are measured for the native and several heavy atom derivatives. the crystals diffract to about 3.5-a resolution.19846365913
acute disseminated histiocytosis-x: in situ immunophenotyping with monoclonal antibodies.the proliferating skin cells in a case of acute disseminated histiocytosis-x (abt-letterer-siwe disease) confirmed by electron microscopy, were characterized by a panel of monoclonal antibodies using an immunoperoxidase technique. the "histiocytes" were found to stain with okt-6 (anti-t6) and anti-hla-dr antibodies. unexpectedly, slight staining was also observed with leu 3a (anti-t4) and okm-1. a proliferative process of t4, t6, hla-dr, okm-1 positive langerhans' cells has not yet been describe ...19846365987
formation of the prohead core of bacteriophage t4 in vivo.formation of the prohead core of bacteriophage t4 was not dependent on shell assembly. in mutant infections, where the production or assembly of active shell protein was not possible, naked core structures were formed. the particles were generally attached to the bacterial inner membrane and possessed defined prolate dimensions. the intracellular yield varied between 15 and 71% of a corresponding prohead yield and was dependent on the temperature of incubation. the products of genes 21 and 22 we ...19846366245
in vitro study on release of thyroid hormone in solitary autonomously functioning thyroid nodules using cell culture method.in vitro release of thyroid hormone was investigated under basal and tsh-stimulated conditions in the solitary autonomously functioning thyroid nodules (aftn). a small portion (0.5 g of wet weight) of the nodules and adjacent thyroid tissues removed surgically from five patients with solitary aftn were prepared for the dispersed cell culture. in the experiment on non tsh-stimulated (basal) conditions, those culture media which were totally replaced on the 5th day after primary culture were utili ...19846398219
triiodothyronine production by isolated rat hepatocytes: characterization and lack of glucoregulatory hormone effects.triiodothyronine (t3) production from thyroxine (t4) was studied in isolated rat hepatocytes. with an initial t4 concentration of 0.56 microm, hepatocyte t3 production was 0.029 +/- 0.003 (sem) pmoles/min/mg protein. t3 production was greater in hepatocytes than in homogenates from the same liver prepared either before or after liver perfusion with collagenase. most t3 produced remained within the cells under the conditions employed. hepatocyte t3 production was dependent on cell number, medium ...19846398264
panning separation for monoclonal antibody-specific t-cell subsets: effects of enzymes and metabolic inhibitors.the mechanisms of "panning," a simple positive cell separation technique, were examined. using monoclonal antibodies to "pan" for t cells (t101+, t4+, and t8+), we obtained enriched populations with 90% purity and viability from unfractionated human peripheral blood lymphocytes (pbl). we found that the "panning" method reflects an active process. it is sodium azide inhibitable and independent of the divalent cation concentration. effective panning does not require capping, patch formation, or dn ...19846398396
the hepatitis b virus as a molecular model for chronic infection: synthesis of hepatitis b surface and e antigens in mouse l cells transfected with closed circular viral dna.linear hepatitis b virus (hbv) dna, excised from a recombinant plasmid with ecor1, was purified by preparative electrophoresis on agarose gels and incubated with phage t4 ligase to form either monomeric or dimeric closed circles. thymidine kinase deficient mouse l cells were cotransfected with thymidine kinase (tk) and circular hbv dnas and grown in hypoxanthine medium. colonies of tk-transformed cells, selected after 3-4 weeks of incubation and subcultured in hat medium, synthesized either hepa ...19846398645
thymosin in the early diagnosis and treatment of high risk homosexuals and hemophiliacs with aids-like immune dysfunction.the adnormal levels of thymosin alpha 1 in acquired immunodeficiency syndrome (aids) patients, depressed t-cell function, thymus pathology, and the restoration of t-cell function by thymosin fraction 5 (tf5) lend support to the hypothesis that the thymus plays a central role in aids. the thymosin alpha 1 assay may provide a means of identifying symptomatic carriers of aids. this paper summarizes the current status of diagnostic studies with thymosin alpha 1 in aids and reports the 1st clinical ...19846398657
molecular organization of the head of bacteriophage teven: underlying design principles.structure and assembly of the bacteriophage t4 head are described as revealed by results obtained in this laboratory. subunit arrangement of the major coat protein, soc and hoc in the head shell has been determined (figs. 2 and 21). two new approaches for studying the assembly pathway are presented: wild type infection at 19 degrees c and gene 23 cold sensitive mutants. we propose an assembly pathway in which the prehead is formed in one direction, starting from the neck and ending at the distal ...19846399817
[group a streptococci: serotypes isolated in a pediatric environment].we examined the incidence of different types of group a streptococci in children with various (mostly respiratory) diseases. the 85.6% of strains assayed were t typable; they belonged more frequently to "5-11-12-27-44" t complex, to type t12, t1, "3-13-b3264" t complex and t4. an increase of type 1 and 4 was found in streptococcal strains isolated more recently.19846400335
lymphocyte subpopulations at the site of "piecemeal" necrosis in end stage chronic liver diseases and rejecting liver allografts in cyclosporine-treated patients.mononuclear cells in the areas of "piecemeal" necrosis in hepatic tissues from patients with different liver diseases were subtyped using monoclonal antibodies and the avidin-biotin-peroxidase complex method. t lymphocytes were the predominant infiltrating cell type in this lesion (greater than 75% of mononuclear cells) regardless of the etiology of the liver disease. m1-positive cells represented about 20% of the infiltrate. b cells were absent and rare leu-7-positive cells (killer, natural kil ...19846366363
results of controlled double-blind study of thyroid replacement in very low-birth-weight premature infants with hypothyroxinemia.the nature of hypothyroxinemia in sick very low-birth-weight (vlbw) infants was evaluated by assessment of the hypothalamic-pituitary axis and by the clinical response to thyroxine (t4) therapy. twenty-three very low-birth-weight infants of gestational age 26 to 28 weeks, whose serum t4 concentrations were 4 micrograms/dl on two occasions, and thyrotropin less than 20 microu/ml, were included in a double-blind study. following a thyrotropin-releasing hormone stimulation test, babies were given e ...19846366725
fluorescent labelling of trna and oligodeoxynucleotides using t4 rna ligase.3'-o-(5'-phosphoryldeoxycytidyl) phosphorothioate and fluorescent 3'-o-(5'-phosphoryldeoxycytidyl) s-bimane phosphorothioate can be ligated to trna by t4 rna ligase. they are also efficient donors for the enzymatic ligation to oligodeoxynucleotides bearing a 3'-cytidine terminus. cytidine 3',5'-bisphosphate is also a substrate for the ligation reaction with dna restriction fragments with a 3'-terminate cytidylic acid residue. oligo- and polynucleotides with a 3'-phosphorothioate group react read ...19846366740
1h nmr (500 mhz) of gene 32 protein--oligonucleotide complexes.in concentrated solutions, gene 32 single-stranded dna binding protein from bacteriophage t4 (gene 32p) forms oligomers with long rotational correlation times, rendering 1h nmr signals from most of the protons too broad to be detected. small flexible n- and c-terminal domains are present, however, the protons of which give rise to sharp resonances. if the c-terminal a domain (48 residues) and the n-terminal b domain (21 residues) are removed, the resultant core protein of 232 residues (gene 32p) ...19846367821
mutagenic specificity of a novel t4 dna polymerase mutant.the in vivo mutational specificity of a novel t4 dna polymerase mutator mutant, tsm19, was determined. two genetic tester systems were used to characterize the mutant. results of our studies indicate that tsm19 promotes transition and transversion mutagenesis and, possibly, frameshift mutagenesis. central g:c base pairs in runs of three or more consecutive g:c base pairs may be target sites for tsm19-induced transitions.19846368313
multiple hormones stimulate the production of somatomedin by cultured human fibroblasts.although immunoreactive somatomedin (ir-sm) secretion by cultured human fibroblasts has been reported, the hormonal control of ir-sm production is not well defined. this study concerns the effects of several hormones and growth factors on ir-sm production by cultured human fibroblasts. platelet-derived growth factor (pdgf) and fibroblast growth factor (fgf) had concentration-dependent stimulatory effects on ir-sm production when added to confluent quiescent cultures. when pdgf, fgf, macrophage g ...19846368579
a cloning strategy for the bacteriophage t4 vs gene.the product of the bacteriophage t4 vs gene, the tau peptide, has been shown to thermally stabilize temperature-sensitive valyl-trna synthetase (ec 6.1.1.9). to clone the bacteriophage t4 vs gene, recombinant pbr322-t4 dna molecules were used to transform escherichia coli cp 790302 (valsts). transformants that grew at 43.5 degrees c on selective medium exhibited some properties indicative of a phage-modified valyl-trna synthetase. the data are consistent with successful cloning of the vs gene an ...19846368747
uv irradiation impairs in vivo encapsidation of bacteriophage t4 dna.t4 dna structural requirements for encapsidation in vivo were investigated, using thin-section electron microscopy to quantitate the kinetics and yields of head intermediates after synchronous dna packaging into accumulated processed proheads. uv irradiation (254 nm) of t4-infected bacteria just before initiation of encapsidation resulted in a reduction in the rate of dna packaged measured by electron microscopy and in the yield of viable phage progeny. in uv-irradiated infections with excision- ...19846368863
mechanisms governing the relative proportions of thyroxine and 3,5,3'-triiodothyronine in thyroid secretion.in subjects with normal thyroid function only a minor part of firculating 3,5,3'-triiodothyronine (t3) originates directly from the thyroid; the majority is produced in the peripheral tissues by deiodination of thyroxine (t4). however, t3 of thyroidal origin constitutes a relatively high fraction of the total t3 produced in many patients with thyroid hyperfunction or hypofunction. such a relatively high t3 content in the secretion of the thyroid could be caused by a low t4/t3 ratio in thyroglobu ...19846369072
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