Purified gamma-glutamyltransferase from hog small intestine was competitively inhibited by glutathione in vitro when L-gamma-glutamyl-p-nitroanilide was used as a substrate. An S-acetyldextran derivative of glutathione inhibited the enzyme as well as glutathione, although dextran had no inhibitory effect. gamma-Glutamyltransferase in the rat small intestine could utilize in situ L-gamma-glutamyl-p-nitroanilide circulated in the lumen, and was inhibited by the impermeable derivative of glutathione which was on the luminal side. These data suggested that the active site of intestinal gamma-glutamyltransferase faced the luminal side of the brush border membrane.

Aniline Compounds↗

PubMed1985

Somatic mutations in the variable region of the lambda 2 chain of M315 suppression of antibodies to the idiotype of M315.

BALB/c mice immunized with purified BALB/c myeloma protein M315 (alpha, lambda 2) produce anti-idiotypic antibody directed predominantly to a combinational (VH-315 + VL-315) determinant(s) of the M315 paratope (Sirisinha and Eisen, 1971; Tungkanak and Sirisinha, 1976). We examined whether the unique B cell response is influenced by pretreatment of mice with fragments or chains derived from M315 before immunization with M315. Intravenous (i.v.) injection of the Fv-315 fragment (VH-315 + VL-315) into normal BALB/c mice seven days before immunization with M315 resulted in marked suppression of anti-M315 idiotype antibodies. Studies on the structural requirement for suppression indicated that VL-315, but not VH-315, is involved. Structural comparison with a defined lambda 2 light (L) chain suggested that three contiguous amino acid residues in the third hypervariable loop of the variable (V) domain of the L chain of M315 are important for down-regulation of production of antibodies to the M315 idiotype.

Animals↗

PubMed1985

[Diagnostic value of angiography in differentiating the degree of the depressed type of gastric cancer].

Endoscopy and superselective angiography has been performed in 68 preoperative patients with the depressed type gastric cancer. The results are summarized as follows. Differentiation of the cancers into the early and the advanced was correct in 91%, and classification of the cancers into 3 groups (1 ; m, 2 ; sm, 3 ; advanced) was correct in 72% by endoscopy. Differentiation of the cancers into the early and the advanced was correct in 90%, and classification of the cancers into 4 groups (1 ; m X sm, 2 ; pm, 3 ; ss X se, 4 ; sei) was correct in 81% by the angiography. The rate of misdiagnosis, taking the early simulating advanced gastric cancer as the early, was 20% by the endoscopy, as compared to 8% by the angiography. Classification of the early simulating advanced gastric cancers into 3 groups (1 ; pm, 2 ; ss X se, 3 ; sei) was correct in 68% by the angiography. Excavated type cancer was likely to be overestimated as to the depth of invasion by the angiography. Poorly differentiated type, scirrhous type, and infiltrative growth with an ill defined border were found difficult to be correctly evaluated by both endoscopy and angiography. Preoperative angiography was useful for appropriate surgical therapy of the gastric cancer.

Adenocarcinoma↗

PubMed1985

[Adverse effects of D-penicillamine in rheumatoid arthritis with reference to prior gold therapy].

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Adolescent↗

PubMed1985

[Preparation of the acetabulum to correct severe acetabular deficiency for total hip replacement--with special reference to stress distribution of the periacetabular region after operation].

The author analysed the radiological results of eighty-three total hip replacements in the patients with severely defective acetabulum secondary to congenital hip dysplasias or failed total hip replacements, after an average follow-up period of three years, paying particular attention to socket loosening. The patients with congenital hip dysplasias were divided into the following four groups: Group 1: The sockets were placed above the level of true acetabulum. Group 2: The sockets were placed in the true acetabulum with the cement used as a filler superolaterally. Group 3: The sockets were placed in the true acetabulum with bone grafts. Group 4: Eccentric sockets were placed in the true acetabulum. The incidence of radiological loosening of the socket was 50% in the group 1, 13% in the group 2, 6% in the group 3 and 75% in the group 4. The patients who underwent revision for socket loosening were also divided into two groups, the one whose acetabula were reconstructed with bone grafts and the other without bone graft. The incidence of radiological loosening of the socket was 28% in the group with bone grafts and 72% in the group without bone graft. The major factor that may have been responsible for socket loosening in these cases was considered to be poor mechanical condition around the socket due to bone deficiency. Two-dimensional finite element analysis was performed to establish the stresses in the periacetabular region after total hip replacement for acetabular deficiency. Model variations include, the conventional plastic socket of 44 mm outside, 28 mm inside diameter placed in false acetabulum or in high level, (2) in true acetabulum using bone cement as a filler, (3) in true acetabulum with bone graft and (4) eccentric socket placed in true acetabulum without bone graft. The ratio of von Mises stress to yield stress of each element were calculated. The results demonstrated that in the periacetabular region, the area superomedial to the socket was at high risk in each model. The area in periacetabular bone where the ratio of von Mises stress to yield stress was more than 20% was almost the same in model (1), (2), (4) and about a half of them in model (3). In conclusion, the most effective method to prevent the socket loosening after total hip replacement in the patient with deficient acetabulum was considered to reconstruct the new spherical acetabulum at anatomical position with bone graft.

Acetabulum↗

PubMed1984

Serotonin immunohistochemistry reveals immature EC cells.

Radioautographic studies of rat duodenal mucosa were carried out after single injections of 3H-thymidine, and the labelling indices of enterochromaffin (EC) cells identified by serotonin immunohistochemistry and by the diazo reaction were compared. The labelling index of EC cells by serotonin immunohistochemistry was 2.3% (mean percentage of 2 rats), while no labelled cells were found in diazo-positive EC cells. This finding indicates that serotonin immunohistochemistry reveals a less mature population of EC cells than conventional techniques such as the diazo reaction.

Animals↗

PubMed1984

Central intravascular papillary endothelial hyperplasia of the mandible.

Light and electron microscopic findings in papillary endothelial hyperplasia of the mandible in a 49-year-old female are reported. The endothelial cell-lined papillary projection into a cystic lumen was examined by light microscopy and characteristic features of the endothelial cells were found by electron microscopy. Factor VIII-related antigen was demonstrated in the endothelial cells by the immunoperoxidase technique.

Antigens↗

PubMed1984

Variegated effects of prostaglandins on spontaneous activity in bovine mesenteric lymphatics.

The effects of PGs (PGA2, PGB2, PGE2, PGF2 alpha, PGI2, and 6-keto PGF1 alpha) were investigated quantitatively in insolated bovine mesenteric lymphatics for elucidating the possible significance of PGs in lymph propulsion. 10(-8) M PGF2 alpha, PGA2, and PGB2 produced recognizable increases of frequency and amplitude of spontaneous contractions. The positive chrono- and inotropic responses were enhanced with increasing concentration of the PGs from 10(-8) to 10(-6) M. Both PGE2 and PGI2 in a concentration range from 10(-8) to 10(-6) M caused dose-related reductions in the amplitude of spontaneous contractions. No decrease in contraction rhythm was observed by the administration of PGI2 and PGE2 at concentrations lower than 5 X 10(-7)M. All of the above-mentioned responses induced by PGF2 alpha, PGA2, PGB2, PGI2, and PGE2 were not inhibited by pretreatment with alpha- and beta-adrenergic blocking agents, muscarinic antagonist, antihistamics, and serotonic antagonist. These findings suggest that PGF2 alpha, PGA2, and PGB2 in a low concentration may facilitate lymph flow of bovine mesenteric lymphatics in the living body, since the spontaneous contractions of lymphatic smooth muscle may drive lymph centripetally in the presence of direction valves. On the other hand, PGI2 and PGE2 may cause an inhibition of lymph transport.

Adrenergic alpha-Antagonists↗

PubMed1984

Diversity at the variable-joining region boundary of lambda light chains has a pronounced effect on immunoglobulin ligand-binding activity.

By recombining lambda light (L) chains having known variable (V) region amino acid or nucleotide sequences with a heavy (H) chain from a myeloma protein or a monoclonal antibody, we obtained reconstituted Igs that differed from each other in sequence by only one or a few amino acid substitutions at known L chain positions. Differences in affinity of the reconstituted Igs for 2,4-dinitrophenyl (DNP) ligands revealed a pronounced effect on Ig binding activity of amino acids at the V-J boundary of the lambda chains. In one instance, two reconstituted Igs that differed about 1000-fold in affinity for epsilon-DNP-aminocaproate differed in primary structure by only a single tyrosine-phenylalanine substitution at the V-J junction (position 98) of their lambda 2 chains--i.e., by only one out of approximately 660 amino acid residues (L + H chains). By focusing on affinity changes, chains with unusual V lambda-J lambda junctional residues were identified. It is possible that because of a critical effect on tertiary structure junctional amino acid variations arising from gene segment assembly (V/J and perhaps V/D/J) constitute an important source of ligand-binding diversity of antibodies.

Amino Acid Sequence↗

PubMed1984

Sympathetic effects on spontaneous activity in bovine mesenteric lymphatics.

To investigate the effects of autonomic nerves on the spontaneous activity, responses of valvular and intervalvular segments of isolated bovine mesenteric lymphatics to 60-strains of pulses (50 V for 0.5 ms at 2 Hz) have been studied under the influence of various drugs. There was a marked difference in response to transmural stimulation between the valvular and intervalvular segments. In the valvular segment, the stimulation arrested the spontaneous activity. However, the rhythm of spontaneous contractions was markedly accelerated during the stimulation in the intervalvular segment. Both inhibitory and excitatory effects were completely blocked by tetrodotoxin and guanethidine, potentiated by cocaine, and unaffected by hexamethonium and atropine. Propranolol blocked the inhibitory effect of the stimulation in the valvular segment. Pretreatment of the intervalvular segment with phentolamine converted the normal excitatory effect of the stimulation into an inhibitory influence. No change in rhythm was brought about by the stimulation in the presence of propranolol and phentolamine in either segment. These results suggest that transmural electrical stimulation causes the release of norepinephrine from postganglionic sympathetic nerve terminals in the vicinity of pacemaker cells and that beta-adrenoceptors are predominant in the valvular region of the lymph vessel.

Animals↗

PubMed1984

High erythroid burst-promoting activity in sera from umbilical cord blood.

Using methylcellulose clonal cell cultures, we examined human erythroid burst-promoting activity (BPA) in sera obtained from umbilical cord blood. BPA was measured on the basis of the number of erythroid bursts (BFU-E) and hemoglobin synthesis when peripheral blood mononuclear cells were cultured with cord blood serum in the presence of 1.0 U/ml erythropoietin (Epo) at low fetal calf serum concentration (10%). Controls were cultured with adult serum. The number of BFU-E and hemoglobin synthesis increased in culture to which cord blood serum had been added, and the enhancing effects of cord blood serum on erythroid burst formation were more pronounced than in control cultures with 2.0 U/ml Epo. No erythroid bursts, however, grew in the cultures with cord blood serum in the absence of Epo. Increased sensitivity of erythroid burst formation to low concentrations of Epo was observed in cultures containing cord blood serum. Dose-relationships between the concentrations of cord blood serum and the number of BFU-E and hemoglobin synthesis were clearly observed. We therefore concluded that the stimulatory effects of cord blood serum on erythroid burst formation may be due to BPA, one of the factors required for the proliferation of erythroid precursors at an early stage.

Adult↗

PubMed1984

Redistribution of flow between canine isolated internal and external carotid arteries by vasoactive substances.

A Y-shaped segment consisting of the common, internal, and external carotid arteries was isolated from the canine carotid artery. The preparation has the advantage of allowing direct comparison of responses to vasoactive substances in the internal and external carotid arteries. It was perfused at a constant rate (within the range of 10-15 ml/min) through the common carotid with either Locke's solution or arterial blood led from a support dog. Adding norepinephrine or epinephrine to the perfusate raised the perfusion pressure, increased the flow along the internal carotid branch, and decreased it in the external carotid branch in the blood-perfused experiments but not in the saline-perfused ones. In contrast, 5-hydroxytryptamine, prostaglandin F2 alpha, and ATP caused a decrease in internal carotid flow and an increase in external carotid flow, raising the perfusion pressure in both experiments. Controlled bleeding of the support dog (at the rate of 4 ml/(kg X min] produced a similar result to that produced by exogenous norepinephrine or epinephrine. These findings may suggest that a redistribution of blood flow between the larger internal and external carotid arteries can be induced by a difference of responsiveness to certain vasoactive substances between the two arteries.

Adenosine Diphosphate↗

PubMed1984

The mode of ATP-induced vasoconstriction in the canine internal carotid artery.

The mode of the ATP-induced vasoconstriction in the internal carotid artery was studied from the physiological and pharmacological points of view. ATP caused dose-dependent vasoconstrictions in the canine internal carotid artery. The ATP-induced vasoconstriction was not affected by pretreatment with phenoxybenzamine, propranolol, atropine, cyproheptadine, or tetrodotoxin. Verapamil suppressed the contractile response. ATP produced no vasoconstriction in a calcium-free Krebs solution containing 1 mM EGTA nor augmentation of Ca2+-induced contraction in potassium-depolarized tissues. These results suggest that an increase of potential-dependent Ca2+ influx into the arterial smooth muscle may play a major role in the ATP-induced vasoconstriction.

Adenosine Triphosphate↗

PubMed1984

[A camera-type planimeter gauge utilizing an area image sensor: with special reference to its application to physiology].

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Animals↗