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Biomedical subjects

J Takeda

Publications and source records attributed to J Takeda.

At least 289 records · Page 16Linked to original sources
PubMed1992

Covalent binding of C3b to C4b within the classical complement pathway C5 convertase. Determination of amino acid residues involved in ester linkage formation.

C5 convertase of the classical complement pathway is a protein complex consisting of C4b, C2a, and C3b. Within this complex C3b binds to C4b via an ester linkage. We now present evidence that the covalent C3b-binding site on human C4b is Ser at position 1217 of C4. We also show that formation of the covalently linked C4b.C3b complex occurs in the mouse complement system and that the C3b-binding site on mouse C4b is Ser at position 1213 which is homologous to Ser-1217 of human C4. Therefore, covalent binding of C3b to a single specific site on C4b within the classical pathway C5 convertase is likely a common phenomenon in the mammalian complement system. Specific noncovalent association of metastable C3b with C4b would occur first, leading to reaction of the thioester with a specific hydroxy group. This is supported by two lines of experimental evidence, one which shows that a mutant C4 that does not make a covalent linkage with C3b is still capable of forming C5 convertase and a second in which the C4b.C3b complex has been demonstrated by cross-linking erythrocytes bearing this C5 convertase.

Amino Acid Sequence↗
PubMed1992

Role of TraT protein, an anticomplementary protein produced in Escherichia coli by R100 factor, in serum resistance.

Escherichia coli K12 strain W3110/SM bearing a plasmid containing the traT gene (traT+ strain) was more resistant to the bactericidal activity of guinea pig serum than the same strain bearing this plasmid without the traT gene (traT- strain). A murine mAb was generated against synthetic TraT peptide (86-99). This antibody reacted only with denatured TraT protein, but it was used for monitoring TraT protein by immunoblotting during purification of the protein. Six mAb were then generated against partially purified traT protein from the solubilized membrane fraction of the traT+ strain. These mAb reacted with the native protein even on living cells, and their F(ab) fragments were found to suppress the inhibitory effect of the TraT protein on the bactericidal activity of serum. TraT protein was purified from solubilized membranes of the traT+ strain by ion exchange and gel filtration chromatographies. The purified TraT protein inhibited the lysis of sensitized erythrocytes by serum complement. Its inhibitory action was mainly on the C6 step. It strongly inhibited the reaction of C6 with EAC14b2a3b and excess C5, C7, C8, and C9. TraT protein also inhibited the reaction of C7-deficient human serum with guinea pig erythrocytes when it was activated by cobra venom factor. It did not inhibit the reaction of preformed C5b6 complexes. However, TraT did not have any effect on the cleavage of 125I[C5] to 125I[C5b] in similar conditions. It also partially inhibited the reaction steps of C4, C5, and factor B and limited guinea pig complement serum in 0.1% gelatin veronal buffered saline, pH 7.4, containing 10 mM EDTA with their respective preceding intermediate cells. It had no effect on either the binding of C3 to EAC14b2a or the cleavage of C3b by factors H and I. TraT protein probably inhibits the formation of C5b6 complex or causes structural alteration of the complex to a nonfunctional form.

Amino Acid Sequence↗
PubMed1992

Expression of mouse-GLUT3 and human-GLUT3 glucose transporter proteins in brain.

Polyclonal anti-peptide antisera were raised to the C-terminal sequence of mouse- and human-GLUT3 glucose transporter isoforms. GLUT3 protein and mRNA expression were investigated by Western blot and Northern blot assays, in a range of tissues and cell lines. Mouse-GLUT3 protein was detected only in rat brain, where it was present in most regions except adenohypophysis and pineal gland. Mouse-GLUT3 was also detected in primary cultured rat cerebellar neurons and the neuronal cell lines PC12 and NG108-15, but not in cultured astroglia. Human-GLUT3 protein was detected in CHO cells transfected with the human-GLUT3 cDNA and in human brain, but not in human placenta or fat. The expression of GLUT3 in rat brain and neurons indicates it is a major neuronal glucose transporter.

Amino Acid Sequence↗
PubMed1992

Cloning of the alpha 1 subunit of a voltage-dependent calcium channel expressed in pancreatic beta cells.

The isoforms of the alpha 1 subunits of voltage-dependent Ca2+ channels expressed in human pancreatic islets were identified by using a pair of degenerate oligonucleotide primers and the polymerase chain reaction (PCR) to amplify mRNAs encoding alpha 1 subunit-like sequences. The sequences of the PCR products indicate that islets express the heart-type alpha 1 subunit as well as a second isoform whose complete sequence has not been previously reported. The sequences of cloned cDNAs encoding the human beta-cell, or neuroendocrine-type, alpha 1 subunit indicate that it is composed of 2181 amino acids. It shares 68%, 64%, and 41% identity with the sequences of the alpha 1 subunits of rabbit heart, skeletal muscle, and brain, respectively, and is predicted to have a similar structure including four homologous domains composed of six membrane-spanning segments each. RNA blotting studies indicate that the beta-cell-type alpha 1 subunit is also expressed in brain as well as in the insulin-producing cell lines RINm5F and beta TC-3; however, it could not be detected by RNA blotting in a third cell line, HIT-T15. In situ hybridization studies revealed expression of beta-cell-type alpha 1 subunit mRNA in beta cells of rat pancreatic islets, implying that this protein may play a role in the regulation of insulin secretion.

Amino Acid Sequence↗
PubMed1992

Human pancreatic beta-cell glucokinase: cDNA sequence and localization of the polymorphic gene to chromosome 7, band p 13.

The glucose phosphorylating enzyme glucokinase plays an important role in the regulation of glucose homeostasis. Studies in rodents indicate that pancreatic Beta cells and hepatocytes express different isoforms of this protein as a consequence of the presence of tissue-specific promoters and exon 1 sequences which are spliced to a shared group of nine exons which encode most of the mRNA and protein. Here, we report the isolation and characterization of cDNA clones encoding human Beta-cell glucokinase. The sequence of human Beta-cell glucokinase shows 97% amino acid identity with that of the cognate rat protein. We also mapped the human glucokinase gene to the short arm of chromosome 7 by analysing its segregation in a panel of reduced human-mouse somatic cell hybrids. In situ hybridization to metaphase chromosomes confirmed the localization of the human glucokinase gene to chromosome 7 and indicated that it was in band p 13. A microsatellite DNA polymorphism that can be typed using the polymerase chain reaction was identified upstream of exon 1 a, the Beta-cell specific first exon. The glucokinase cDNA clone and highly informative DNA polymorphism will be useful for examining the role of this gene in the pathogenesis of diabetes mellitus.

Amino Acid Sequence↗
PubMed1992

Improved PCO2 monitoring during high frequency jet ventilation.

During high frequency jet ventilation (HFJV), it has been shown that Pa(CO)(2) can be predicted by capnography when the frequency was temporarily reduced to obtain a steady expiratory CO(2) tension (P et(CO)(2)). The influence of the sampling site of expiratory gas in the airway and the driving pressure of the ventilator on the difference between Pa(CO)(2) and P et(CO)(2) was investigated in ten adult patients who underwent general anesthesia. During HFJV (frequency: 100 bpm, inspiratory duty cycle; 30%), its frequency was temporarily reduced to 10 bpm in twelve different condition; i.e., 3 different driving pressures (Pd; 20, 30, and 40 psi) at 4 different sampling sites (d; 0, 2, 5, and 10 cm in the endotracheal tube). Both P et(CO)(2) and Pa(CO)(2) were measured simultaneously, and their difference was evaluated by using Student's t-test. The difference between Pa(CO)(2) and Pmax(CO)(2) (the maximum P(CO)(2) value in the airway during exhalation) was minimal, when Pd was greater than 30 psi, and d was greater than 5 cm. The present study suggests that better prediction of Pa(CO)(2) can be done by P et(CO)(2) during HFJV, when d and Pd were set as large as possible to obtain stable expiratory P(CO)(2) curve.

Journal Article↗
PubMed1992

Evaluation of gastric tube with esophageal thermister (Thermosump).

The accuracy and the feasibility of esophageal temperature measured by a new gastric tube. Thermosump, which is incorporated with a esophageal thermister, was evaluated in anesthetized dogs (n = 6) and men (n = 59). In dogs, esophageal temperature measured by Thermosump was correlated well with the temperatures measured by the conventional esophageal thermister, and also by the pulmonary artery catheter (r = 0.98, 0.98, respectively). In anesthetized men, correlation between esophageal temperature by Thermosump and rectal, or bladder temperature was good during surgery of extremities (r = 0.81, 0.80, respectively). But during abdominal surgery, correlation between esophageal and bladder temperature was relatively poor (r = 0.50). Insertion of the tube, and suction of gastric fluid through the tube were easy without any complication. This newly developed gastric tube with a esophageal thermister was safe, and useful for measuring esophageal temperature.

Journal Article↗
PubMed1992

Kinetics of inter-heavy chain disulfide bond formation of liganded and unliganded human immunoglobulin G by radioimmunoassay.

Monoclonal antibodies (mAbs) to the hinge region of human IgG1 immunoglobulins were prepared by immunization with a proteolytic fragment of hinge segment coupled to keyhole limpet hemocyanin. A mAb, 4G3, was obtained capable of binding to intact IgG but not to partially reduced IgG. Using this mAb, inter-heavy (H) chain disulfide bond formation from partially reduced anti-tetanus antibodies (Abs) in the presence or absence of antigens (Ags) was studied by solid phase radioimmunoassay. When the Abs were partially reduced in solution and then coated to plastic plates, only 10% regeneration of inter-H chain disulfide bonds occurred after reoxidation, although 100% formation occurred in solution [Kishida et al., J. Biochem. (Tokyo) 79, 91-105 (1976)]. This difference in the extent of disulfide bond formation can be explained by the fact that there are two convertible isomers in solution, Conformer I and II, one of which (Conformer I) can form disulfide bonds but is present as a minor component. Since the motion of IgG molecules on plates is restricted by hydrophobic interactions, the two conformers are not convertible as in solution. Therefore only Conformer I which existed before coating formed inter-H chain disulfide bonds. Similar kinetic measurements were performed using plates coated with tetanus toxoid. Abs, partially reduced in solution and then allowed to react with Ags on the plate were able to completely regenerate their inter-H chain disulfide bonds, although the rate of reaction was slow. These results can also be explained by the fact that the two isomers are convertible since Ag-Ab complexes are dissociable. Ag-binding therefore did not significantly perturb conformation of the hinge segments. In addition, no difference between liganded and unliganded Abs was observed in the binding of anti-hinge mAbs. These results imply little or no contribution of the hinge region to transmission of the signal produced by Ag-binding to Fc.

Amino Acid Sequence↗
PubMed1992

Deficient surface expression of glycosylphosphatidylinositol-anchored proteins in B cell lines established from patients with paroxysmal nocturnal hemoglobinuria.

Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired type hemolytic disorder. Hematopoietic cells of patients with PNH are deficient in glycosylphosphatidylinositol (GPI) anchored membrane proteins. Since some membrane-bound complement inhibitors, such as CD59 and decay accelerating factor (DAF), are GPI anchored proteins, abnormal cells from patients with PNH are sensitive to complement attack. Their myeloid and erythroid cells are affected more than their lymphoid cells. Patients whose B cells were severely deficient in GPI anchored proteins were chosen to establish cell lines by Epstein-Barr virus mediated transformation. The lines established (SS-1-, TK-1-, and TK-14- cell lines) had the following characteristics of PNH. First, GPI anchored proteins were completely absent from the surface of SS-1- and TK-14- cells, and were expressed at very low levels on TK-1- cells, whereas polypeptide anchored proteins were normally expressed on these three lines. Secondly, DAF mRNAs of the SS-1- cell line were qualitatively and quantitatively indistinguishable from those of a control, wild-type cell line. Third, pro-CD59 and pro-DAF molecules were detected intracellularly in these cell lines, their pro-CD59 being smaller and more hydrophilic than that from a wild-type cell line. These cell lines should be useful in further studies on the pathogenesis of PNH.

Antigens, CD↗
PubMed1992

Serum and urinary inorganic fluoride concentrations after prolonged inhalation of sevoflurane in humans.

Serum and urinary concentrations of inorganic fluoride were measured before and after sevoflurane anesthesia in 10 patients without renal disease, who were scheduled for surgery lasting 13.4 +/- 0.9 h (mean +/- SE). The mean concentration of serum inorganic fluoride reached a maximal value of 42.5 +/- 4.5 mumol/L at the end of anesthesia. However, 5 of 10 patients had serum inorganic fluoride concentrations that exceeded 50 mumol/L (i.e., the nephrotoxic dose). A positive correlation was found between serum inorganic fluoride concentration and anesthetic dose. The largest urinary excretion of inorganic fluoride was 1804 +/- 378 mumol/day in the first postoperative day and rapidly decreased thereafter. We concluded that lengthy sevoflurane anesthesia created serum inorganic fluoride concentrations that could influence renal function, although nephrotoxicity was not demonstrated in our biochemical study.

Aged↗
PubMed1992

[Work history, health conditions and hearing loss of Ishigaki fishermen].

Based on our previous health survey among Ishigaki fishermen in 1979, this study aimed at clarifying the relations of their work histories to physical characteristics, physiological functions, blood conditions and hearing levels. Medical examination was conducted in 1987 on 118 fishermen inclusive of 33 followed-up fishermen, and in 1989 noise-level and noise-induced temporary threshold shift of hearing was measured for different fishing methods. The results were as follows; 1) Fishing history was not specifically associated with any physical characteristics. 2) High HDL cholesterol, which was observed among divers using diving apparatus, was considered to be a survival effect for divers, since HDL cholesterol is amplified by intensive muscle work. 3) Abnormalities of ECG except for a high R wave were notably observed among the divers, who once changed from unassisted diving to diving with apparatus and then to fishing lines. The main reason for switching jobs was claimed to be caisson disease, and it was suggested that diving with apparatus was related to a high risk of health hazards in the central nervous system and/or respiro-circulatory system. 4) Acoustic acuity greatly declined with aging, and which was commonly observed in groups with different work histories. By way of explanation, exposure to ship engine sounds during daily travelling was the most likely cause. It was also revealed that several hours' exposure to the engine sounds was needed to detect a temporary threshold shift of hearing before and after work.

Cardiovascular Diseases↗
PubMed1992

Massive gastric cancer in a patient with a negative Gregory antigen (Gy (a-)), a rare blood group.

A case of a massive advanced gastric cancer of the Borrmann type III in a patient with the rare blood group of negative Gregory antigen (Gregory (a-)) is reported. On admission, he was found to have a severe anemia (Hb 6.1 g/dl) requiring a direct blood infusion. He had never received a blood infusion, previously. In blood crossmatching tests, his blood was agglutinated by all the antisera for the common antigens, and he was discovered to have a rare blood type of Gregory (a-). There was no appropriate blood donor in his family. Before the operation, only 600 ml (6 i.u.) of frozen red blood cells could be found in storage from only 2 people with Gregory (a-), O blood type and Rh (+) in Japan. To increase the RBC, erythropoietin (3000 i.u.) was administered 6 times; and the Hb increased to 7.4 g/dl. However, the anemia remained and 200 ml (2 i.u.) Gregory (a-) blood was infused, preoperatively. The final preoperative Hb was 7.8 g/dl and the RBC was 283 x 10(4)/mm3. A massive gastric cancer directly infiltrated the pancreas, the transverse colon and the mesocolon. A palliative subtotal gastrectomy with combined resection of the transverse colon was performed. The intraoperative blood loss was 460 ml and the volume of blood infused was 400 ml (4 i.u.). The postoperative Hb was 7.9 g/dl, and more blood was needed. However, there was no more Gregory (a-) donor blood in storage in Japan.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenocarcinoma↗
PubMed1992

A retrospective study of resected gastric cancers.

From 1976 to 1989, a total of 1303 patients with gastric cancers underwent gastrectomies in the First Department of Surgery, Kurume University Hospital. Of these, 358 (27.5%) were total gastrectomies, 84 (6.4%) were proximal gastrectomies and 825 (63.1%) were distal gastrectomies. The 5-year survival rate was 44.8% after the total gastrectomies, 38.9% after the proximal and 72.4% after the distal gastrectomies. The 5-year survival rate was 86.2% with the absolute curative resection, 36.3% with the relative curative resection, 29.3% with the relative non-curative resection and 9.4% with the absolute non-curative resection. Macroscopically, the 5-year survival rate was 95.1% for type 0 (early cancers), 61.3% for Borrmann type 1, 58.8% for Borrmann type 2, 37.5% for Borrmann type 3 and 16.5% for Borrmann type 4. According to the pathological cancer stage, the 5-year survival rate was 94.8% for stage I, 79.3% for stage II, 49.2% for stage III and only 11.3% for stage IV.

Gastrectomy↗
PubMed1992

Invisible cardia cancer metastasis to the diaphragm.

The best surgical procedure to treat a carcinoma in the gastric cardia remains a controversy because the carcinoma is often advanced and there are other unknown factors. In this article the incidence of invisible metastasis from cardia cancer to the diaphragm will be analyzed using an experimental cardia cancer model and clinical studies. An experimental cardia cancer was induced by an endoscopic injection of VX2 cancer cells into the submucosal layer of the esophago-gastric junction in rabbits using a 27G needle and an Olympus BF-4B2 bronchofiberscope. A total of 26 cardia cancer models for Borrmann type 2 or 3 were produced. Of these, six (23%) had visible cancer metastases in the diaphragm, including 4 cases with direct invasion and 2 cases with peritoneal dissemination on the surface of the diaphragm. Four (20%) of the remaining 20 were histologically found to have macroscopically-invisible cancer metastases mainly in the lymph vessels of the left hemidiaphragm. From 1985 to 1988, 22 clinical cases of cardia cancer were managed by a combined total gastrectomy with a partial diaphragm resection through a left thoracoabdominal approach. When widely resected, reconstruction was performed using a latissimus dorsi muscle flap. Six (27%) of these 22 were also histologically found to have macroscopically-invisible cancer metastases to the diaphragm, including 1 (11%) of the 9 well-differentiated type and 5 (39%) of 13 poorly-differentiated type adenocarcinomas.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

Retrospective studies of gastric subserosal (ss) cancer--in comparison to pm- and se-cancers.

The deepest gastric cancer invasion into the tela subserosa is expressed as the ss-cancer. Subserosal gastric cancers (ss) can be divided into 4 subtypes; ss alpha, ss beta, (ss gamma) and ss gamma, pathologically. These four subtypes were compared to cancerous invasion into the muscularis propria (pm-cancer) and cancerous invasion with serosal exposure (se-cancer). During the 10 years from 1979 to 1988, a total of 938 cases with gastric cancer were resected in the First Department of Surgery, Kurume University Hospital. Of these, 104 (11.1%) cases were ss-cancers, consisting of 28 (27%) cases of ss alpha, 33 (32%) cases of ss beta, 4 (3%) cases of (ss gamma) and 39 (38%) cases of ss gamma. Pm-cancers and ss-cancers were most frequently observed in Borrmann type 2, macroscopically, and in the differentiated type, histologically. On the other hand, se-cancers were frequently observed in Borrmann type 3 and in an undifferentiated type. Positive lymph node metastases were found in 49.1% of pm-cancers, in 50.0% of ss-cancers and in 79.9% of se-cancers (p < 0.01), with no statistical difference in the positive lymph node metastasis rates for the subdivisions of ss-cancer. In ss-cancer, however, there was a statistical difference in prognosis according to the tumor size, and according to the degree of subserosal infiltration. The 5-year survival rate was 82.3% for pm-cancer, 75.0% for ss-cancer and 34.7% for se-cancer (p < 0.01).

Female↗