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Biomedical subjects

S Tanaka

Publications and source records attributed to S Tanaka.

At least 91 records · Page 5Linked to original sources
PubMed2004

Deficient cell proliferation in palatal shelf mesenchyme of CL/Fr mouse embryos.

How secondary palate formation is affected in the cleft lip genotype remains poorly understood. The purpose of this study was to analyze regional patterns of cell proliferation in CL/Fr mouse embryos with or without cleft lip. Pairs of palatal shelves were dissected at E13.5 from CL/Fr normal embryos (CL/Fr-N), CL/Fr embryos with bilateral cleft lip (CL/Fr-BCL), and a control strain of C57BL embryos (C57BL). The explants were examined histologically after 48 hrs of organ culture. Cell kinetics for proliferation in the palatal shelves was examined at E13.5 by the bromodeoxyuridine method in vivo. The CL/Fr-BCL palates fused as well as the CL/Fr-N palates in vitro. There were inter-group differences in the absolute number of BrdU-positive cells and the ratio of positive/(positive+negative) cells in the palate's mesenchyme (C57BL > CL/Fr-N > CL/Fr-BCL) and epithelium (C57BL > CL/Fr-N = CL/Fr-BCL). These findings indicate that a cleft palate follows reduced cell proliferation of secondary palatal mesenchyme in CL/Fr mice.

Animals↗
PubMed2004

[Squamous cell bronchogenic carcinoma with syndrome of inappropriate secretion of antidiuretic hormone].

Non-small cell lung cancer with syndrome of inappropriate secretion of antidiuretic hormone (SIADH) is rare. A case of squamous bronchogenic carcinoma with SIADH is reported. A 64-year-old man was admitted with 2 cm nodule of the left lung on chest radiography. Transbronchial lung biopsy revealed the squamous cell carcinoma. His past history included hypertension and hemiparesis due to brain infarction. Serum sodium level was low (122 mEq/l) and serum osmolarity was low (271 mOsm/kgH2O). However, urine sodium level was high (82 mEg/l) and urine osmolarity was high (461 mOsm/kgH2O). Renal and adrenal function was normal. He was diagnosed with cT1N0M0 squamous bronchogenic carcinoma accompanied by SIADH. He underwent left upper lobectomy with lymph node dissection. Five months after the operation, serum sodium level returned to normal. He remains well 20 months after the operation.

Carcinoma, Bronchogenic↗
PubMed2004

Outcomes of kidney transplants from non-heart-beating deceased donors as reported to the Japan Organ Transplant Network from April 1995-December 2003: a multi-center report.

Between April 1995-December 2003, 1,324 deceased donor kidney transplantations were performed in 139 transplant institutes in Japan. Of these, 45 transplants were from heart-beating and 1,279 transplants were from non-heart-beating deceased donors (NHBDD). Clinical outcomes for the 1,279 recipients of NHBDD kidney transplants were investigated. The overall 5-year patient and graft survival rates were 90% and 72%, respectively. A total of 112 NHBDD kidney grafts never functioned after transplantation and the recipients had to remain on dialysis. The causes of nonfunction were rejection, primary nonfunction, death, thrombosis and others in the order of the incidence. The major causes of graft loss were nonfunction, death, chronic rejection and acute rejection in that order. Major causes of recipient deaths were pneumonia, sepsis and CVA within 12 months, and heart diseases, sepsis, malignancy and pneumonia more than 12 months after transplantation. Kidneys from female donors, donors aged 15 or less or over age 60, donors with extrinsic causes of death other than head trauma, recipients over age 60 and those with diabetic nephropathy as their original disease were found to be at risk for poor graft survival. The lowest and last donor serum creatinine level did not influence the incidence of nonfunction or graft survival. However, graft survival was significantly poorer among recipients of older "expanded" donor kidneys than for recipients of younger grafts. The warm and total ischemia times should be kept shorter than 30 minutes (better 15 minutes), and 12 hours, respectively to minimize the incidence of nonfunction and early graft loss. It is especially important in cases with WIT over 30 minutes that the total ischemia should be kept within 12 hours. Cannulation before cardiac standstill was important to reduce the incidence of nonfunction and achieve high graft survival rates with NHBDD kidneys. The discontinuance of ventilator support also reduced the incidence of graft nonfunction. The combination of CsA or Tacrolimus and MMF as both the induction and maintenance regimen significantly improved graft survival. The use of either anti-T cell antibodies or basiliximab was also associated with significantly better graft survival for NHBDD kidneys. The combination of basiliximab, CsA and MMF resulted in a graft survival rate of 98% at one and 2 years.

Adolescent↗
PubMed2003

Serological relationships among genotypic variants of betanodavirus.

Betanodaviruses, the causative agents of viral nervous necrosis or viral encephalopathy and retinopathy, are divided into 4 genotypes based on the coat protein gene (RNA2). In the present study, serological relationships among betanodavirus genotypic variants were examined by virus neutralization tests using rabbit antisera raised against purified virions of strains representative of each genotype. All 20 isolates examined shared epitopes for neutralizing, but they fell into 3 major serotypes (A, B, C). This sero-grouping is in part consistent with their genotypes, i.e. Serotype A for striped jack nervous necrosis virus (SJNNV) genotype, Serotype B for tiger puffer nervous necrosis virus (TPNNV) genotype, and Serotype C for both redspotted grouper nervous necrosis virus (RGNNV) and barfin flounder nervous necrosis virus (BFNNV) genotypes. The serological relatedness between RGNNV and BFNNV genotypes may result from their relatively higher similarity in RNA2 sequences. In neutralization tests using antisera of kelp grouper Epinephelus moara, which were raised against recombinant coat proteins representing each genotype, anti-SJNNV and anti-TPNNV sera neutralized only the homologous strain, and anti-RGNNV and anti-BFNNV sera reacted with both RGNNV and BFNNV strains. The present serological findings will be important in investigating the infectivity and host-specificity of betanodaviruses and in developing vaccines for the disease.

Amino Acid Sequence↗
PubMed2003

An anatomical study of the levator veli palatini and superior constrictor with special reference to their nerve supply.

We dissected 50 head halves of 25 Japanese cadavers (10 males, 15 females) to investigate the innervations of the levator veli palatini (LVP) and superior constrictor pharyngis. The branches supplying the LVP were classified into the following three types according to their origins: supplying branches that originated from the pharyngeal branch of the glossopharyngeal nerve (type I, four sides, 8%), branches that originated from a communicating branch between the pharyngeal branches of the glossopharyngeal and vagus nerves (type II, 36 sides, 72%), and those that originated from the pharyngeal branch of the vagus nerve (type III, 10 sides, 20%). In previous studies, supplying branches of type I were seldom described. Regarding the innervation of the superior constrictor, some variations were observed, and we consider it likely that there is a close relationship between these variations and the type of innervation of the LVP.

Female↗
PubMed2003

Choledocholithiasis caused by migration of a surgical clip into the biliary tract following laparoscopic cholecystectomy.

As experience with laparoscopic cholecystectomy (LC) has increased, so have the number and variety of complications. We report a case of choledocholithiasis caused by migration of a surgical clip applied during LC. A 57-year-old Japanese man who had undergone LC 6 years previously was referred to our hospital with pruritus and jaundice. Magnetic resonance cholangiopancreatography and ultrasonography revealed a solid mass in the common hepatic duct and dilatation of the intrahepatic bile ducts. Abdominal arteriography demonstrated interruption of the right hepatic artery by surgical clips. Five days after a biopsy of the mass was performed through a percutaneous transhepatic biliary drainage tube, the mass moved to the terminus of the common bile duct along with one of the surgical clips. A basket catheter was used to remove the mass via endoscopy. Despite the fact that other clips in the common hepatic duct were partially exposed, the patient has been well for 2 years with no additional interventions.

Bile Ducts, Intrahepatic↗
PubMed2003

The long-term effect of Helicobacter pylori eradication therapy on symptoms in dyspeptic patients with fundic atrophic gastritis.

AIM: To investigate whether curing Helicobacter pylori infection improves symptoms over the long-term in Japanese patients with nonulcer dyspepsia and fundic atrophic gastritis. METHODS: Ninety H. pylori-positive dyspeptic patients with fundic atrophic gastritis were enrolled in this study. We performed a randomized double-blind placebo-controlled trial comparing triple therapy (n=45) with that of placebo alone (n=45). Inflammation and mucosal atrophy were scored according to the Updated Sydney System. Symptoms were scored on a scale of 0 to 3 for six items. Fasting samples of gastric juice were taken before endoscopy, and gastric pH was determined. Serum gastrin and pepsinogen levels were measured, and body mass index was determined. These patients were followed up for 3 years, and all measures were evaluated both before and after therapy. RESULTS: Significant improvement in dyspeptic symptoms and gastritis scores, significant decrease in gastric pH, and significant increase in body mass index were found after 3 years eradication in nonulcer dyspepsia patients treated successfully for H. pylori infection. There were no significant changes in the placebo group. CONCLUSION: Our study shows that eradicating of H. pylori results in significant long-term reduction in symptoms of nonulcer dyspepsia with fundic atrophic gastritis.

Adult↗
PubMed2003

Long-term observation of reflux oesophagitis developing after Helicobacter pylori eradication therapy.

BACKGROUND: Development of reflux oesophagitis after Helicobacter pylori eradication therapy has been reported, but the prognosis is not well known. AIM: To evaluate the prognosis of patients with reflux oesophagitis that developed after eradication therapy by long-term observation. METHODS: Forty-five patients who developed reflux oesophagitis after successful H. pylori eradication therapy were followed up prospectively. All 45 patients were followed up by endoscopy more than 3 years after onset of reflux oesophagitis (3-year follow-up group) and nine were followed up more than 5 years after onset (5-year follow-up group). Endoscopic observations were performed yearly or when upper gastrointestinal symptoms recurred. Reflux oesophagitis was graded according to the Los Angeles Classification System. Presence of gastro-oesophageal reflux symptoms and medication of proton pump inhibitors, H2-blockers or prokinetics were investigated at final endoscopy. RESULTS: All patients were classified as grade A or B at initial endoscopy. At final observation, the grade of reflux oesophagitis improved in 35/45 (78.8%) patients from the 3-year follow-up group and 7/9 (78.8%) patients from the 5-year follow-up group. Reflux oesophagitis progressed from grade A to B in only four (8.9%) patients from the 3-year follow-up group and in no patients in the 5-year follow-up group. No patient progressed to grade C or D. Gastro-oesophageal reflux symptoms were seen in 12 patients (26.7%) from the 3-year follow-up group and four patients (44.4%) from the 5-year follow-up group. Among them, medication was needed continuously in only six (13.3%) and two (22.2%) patients, respectively. CONCLUSIONS: Reflux oesophagitis, which develops after H. pylori eradication therapy, rarely becomes a long-term clinical problem among patients who complete therapy successfully.

Amoxicillin↗
PubMed2003

Antiapoptotic effect of haem oxygenase-1 induced by nitric oxide in experimental solid tumour.

Induction of haem oxygenase-1 (HO-1) may provide an important protective effect for cells against oxidative stress. Here, we investigated the mechanism of cytoprotection of HO-1 in solid tumour with a focus on the antiapoptotic activity of HO-1. Treatment of rat hepatoma AH136B cells with the HO inhibitor zinc protoporphyrin IX (ZnPP IX) or tin protoporphyrin IX resulted in extensive apoptotic changes of tumour cells both in vivo and in vitro. Caspase-3 activity of the ZnPP IX-treated hepatoma cells increased significantly. Moreover, ZnPP IX-induced apoptosis was completely inhibited by simultaneous incubation with a specific caspase-3 inhibitor and was partially abrogated by bilirubin, a reaction product of HO. In vivo ZnPP IX treatment did not affect nitric oxide (NO) production and tumour blood flow. Western blot analyses showed that HO-1 expression in AH136B cells was strongly upregulated by NO donors, for example, S-nitroso-N-acetyl penicillamine and propylamine NONOate in vitro; conversely, it was remarkably reduced in vivo by pharmacological blockade of NOS. We conclude that HO-1 may function in antiapoptotic defense of the tumour, and thus it may have important protective and beneficial effects for tumour cells against oxidative stress induced by NO, which is produced in excess during solid tumour growth in vivo.

Animals↗
PubMed2003

Ethnic differences in abdominal visceral fat accumulation between Japanese, African-Americans, and Caucasians: a meta-analysis.

A meta-analysis was performed in order to test the hypothesis that Japanese have a greater amount of abdominal visceral fat (AVF) relative to abdominal subcutaneous fat (ASF) than Caucasians. Data were derived from published studies that included mean values for AVF and ASF areas, measured using computed tomography, and age for native Japanese, African-Americans, and Caucasians of both genders. Mean values from each study were used as single data points. A significant difference in AVF was observed between Japanese and Caucasian populations after adjusting for ASF, age, and sex ( p<0.05). However, the difference in AVF between Japanese and Caucasian females was lower than that between African-American and Caucasian females.

Abdomen↗
PubMed2003

Importance of re-examination for medulloblastoma and atypical teratoid/rhabdoid tumor.

Medulloblastoma may can be difficult to distinguish from atypical teratoid/rhabdoid tumor (AT/RT), since they resemble each other histologically. We re-examined whether AT/RT was included among cases who had been diagnosed as medulloblastoma. All of fifteen medulloblastomas (10 males and 5 females) diagnosed at the Kitasato University Hospital were collected and stained immunohistochemically. Two cases originally diagnosed as medulloblastoma were reclassified as AT/RT based on histological re-examination including immunohistochemical studies. While these two cases of AT/RT were found during infancy, only one medulloblastoma was found in infancy.Histologically, small rhabdoid cells and large, pale, bland cells were common but typical rhabdoid cells were not seen in the two AT/RTs. Gland-like structures were also seen. The tumor cells in AT/RT, but not those in medulloblastoma, were immunoreactive for vimentin, epithelial membrane antigen and smooth muscle actin. In conclusion, if a diagnosis of medulloblastoma is made histologically, it should be confirmed immunohistologically, since it is difficult to distinguish AT/RT from medulloblastoma. When appropriate treatment was specifically targeted at AT/RT it may improve the outcome.

Adolescent↗
PubMed2003

Autoimmune hepatitis in a patient with systemic lupus erythematosus.

We report a female patient with systemic lupus erythematous (SLE), hyperbilirubinemia and high serum value of ALT. International autoimmune hepatitis (AIH) score showed definite AIH before treatment, but autoantibodies could not make a differential diagnosis of AIH and SLE-associated hepatitis. Liver biopsy showed periportal hepatitis with lymphoplasmacytic infiltration, but neither parenchymal collapse nor rosette formation could be found. Pericarditis, pleuritis and nephritis were improved as well as liver injury after administration of prednisolone, and no repeated attack has been present these 4 years. Our case suggested invalidity of AIH score among patients of SLE, and liver histology should be inferred most important at present to make a differential diagnosis of lupus hepatitis or AIH in patients with SLE.

Biopsy, Needle↗
PubMed2003

Involvement of arginine vasotocin in reproductive events in the male newt Cynops pyrrhogaster.

Effects of arginine vasotocin (AVT) on reproductive events such as courtship behavior, pheromone release, and spermatophore discharge were investigated in the male newt Cynops pyrrhogaster. AVT enhanced the incidence and frequency of androgen-induced courtship behavior. In this case, AVT was likely to act centrally because the behavior was evoked with a much smaller amount of AVT when the hormone was administered intracerebroventricularly than when given intraperitoneally. Involvement of endogenous AVT in spontaneously occurring courtship behavior was also evidenced by the fact that administration of a V1 (vasopressor) receptor antagonist, [d(CH2)5(1), Tyr(Me)2, Arg8-vasopressin] suppressed the expression of the courtship behavior. The water in which AVT-treated males had been kept showed considerable female-attracting activity as compared with the water in which saline-injected males had been kept. Moreover, the content of sodefrin, a female-attracting pheromone in the abdominal gland, was decreased by the intraperitoneal injection of AVT, suggesting that the neurohypophyseal hormone stimulated the release of sodefrin from the abdominal gland into the water. AVT induced contraction of the excised abdominal gland concentration-dependently, and, again, the V1 receptor antagonist suppressed the AVT-induced contraction. Thus, we concluded that AVT induces the pheromone discharge, acting peripherally on a contractile structure of the abdominal gland. AVT was also found to induce spermatophore deposition in the male kept in the absence of the female. Administration of the V1 receptor blocker to the sexually developed males suppressed the spermatophore deposition. All these results indicate the involvement of AVT in reproductive events acting centrally and peripherally.

Animals↗
PubMed2003

Occurrence of prohormone convertase-like substances in the neural complex cells of the ascidian Halocynthia roretzi.

Our previous study on the distribution of adrenocorticotropin (ACTH)-like substances in the neural complex (cerebral ganglion, dorsal strand, and neural gland) of an ascidian Halocynthia roretzi revealed that some of the cells in the cerebral ganglion and the cells scattered along the dorsal strand were immunopositive with antiserum against ACTH. In order to ascertain whether these cells are equipped with prohormone convertases, we performed immunohistochemical studies on the neural complex by using antisera against PC1 and PC2. A considerable number of cells around the dorsal strand and a few cells in the neural ganglion were immunopositive with PC1 and/or PC2 antibodies. Immunoelectron microscopic study demonstrated that some granulated cells situated in the cerebral ganglion and along the dorsal strand contained PC1- or PC2-like substances within their secretory granules. Western blot analysis revealed the presence of 66-kDa PC1-like and 70-kDa PC2-like substances in the neural complex. Moreover, immunostaining of consecutive sections showed that the majority of the cells containing PC1- and/or PC2-like substances corresponded to the cells immunoreactive with antisera against ACTH and CLIP but not to those immunoreactive with an antiserum against PRL. Cells belonging to the neural gland neither contained electron-dense granules nor showed immunoreactivity with any antisera employed in this experiment. The possibility that some of the cells situated in the cerebral ganglion and along the dorsal strand are progenitors of vertebrate adenohypophyseal cells is discussed.

Adrenocorticotropic Hormone↗
PubMed2003

Comparison of structure-activity relations of corazonin using two different bioassay systems.

The structure-activity relations of [His(7)]-corazonin were studied using two different bioassay systems; i.e. inhibitory effect on spinning rate in the silkworm, Bombyx mori, and darkening response in albino nymphs of the migratory locust, Locusta migratoria. Deletion of the N-terminus, shortening of the peptide and single amino acid substitutions reduced activity in a similar manner except for the minimum effective dose in the two insects. The results also revealed that the residues at position 1, 3 and 5 were particularly important for biological activity. Despite the different physiological affects, the two insect species exhibited similar structure-activity relationships, suggesting that they might have similar receptor systems.

Amino Acid Sequence↗
PubMed2003

Changes in the brain kappa-opioid receptor levels of rats in withdrawal from physical dependence upon butorphanol.

Changes in kappa-opioid receptor levels have been implicated in the development of physical dependence upon and withdrawal from the mixed agonist-antagonist opioid, butorphanol. Immunoblotting analysis was performed to determine the levels of kappa- and mu-opioid receptors in brain regions of rats in withdrawal from dependence upon butorphanol or morphine. Physical dependence was induced by a 72 h i.c.v. infusion with either butorphanol or morphine (26 nmol/microl/h). Withdrawal was subsequently precipitated by i.c.v. challenge with naloxone (48 nmol/5 microl/rat), administered 2 h following cessation of butorphanol or morphine infusion. Immunoblotting analysis of kappa-opioid receptors from butorphanol-withdrawal rats showed significant increases in 11 of 21 brain regions examined, including the nucleus accumbens, amygdala, dorsomedial hypothalamus, hypothalamus, paraventricular thalamus, thalamus, presubiculum, and locus coeruleus, when compared with saline treated, non-dependent controls. In addition, significant reductions were found in the hippocampus and in cortical brain regions, including the parietal cortex and temporal cortex from butorphanol-withdrawal rats. These findings contrasted with those from morphine-withdrawal rats, in which the only changes noted were increases in the thalamus and paraventricular thalamus. Changes in the levels of the mu-opioid receptor protein were observed in 11 of 21 brain regions examined in morphine-withdrawal rats, but only in three of 21 in butorphanol-withdrawal rats. These results implicate a substantive and largely unique role for kappa-opioid receptors in mediation of the development of physical dependence upon, and the expression of withdrawal from, butorphanol, as opposed to the prototypical opioid analgesic, morphine.

Animals↗
PubMed2003

Microstructure analysis of calcium phosphate formed in tendon.

The surface of soft tendon tissue has been modified using calcium phosphate in order for the tendon to directly connect with hard bone and reconstruct an injured ligament. Calcium phosphate was coated onto the tendon in a soaking process using alternating a CaCl(2) (200 mM) and a Na(2)HPO(4) (120 mM) solution. According to SEM/EDX observations, calcium phosphate was formed, not only on the tendon surface, but also inside the tendon tissue. When the tendon was treated with seven soaking cycles, calcium phosphate was detected between 0-500 microm from the tendon surface. According to TEM observations, the crystal morphology of calcium phosphate depends on the distance from the surface. Hydroxyapatite crystals were observed near the surface, while octa-calcium phosphate crystals could be observed further from the surface, thus at initial soaking. The crystals were formed on collagen fibrils in spaces between the collagen fibrils with the c-axes of the crystals aligned parallel with the collagen fibrils. This finding suggests Ca(2+) ions to interact with the tendon surface, most probably with the carboxyl functional groups of collagen, and subsequently forming nucleation centers for the crystals.

Journal Article↗