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Biomedical subjects

S Nishioka

Publications and source records attributed to S Nishioka.

At least 19 recordsLinked to original sources

Photorearrangement of vinylidenecyclopropanes to 1,2,3-butatriene derivatives.

[reaction: see text] Photoirradiation of benzene solutions containing 1-diarylvinylidene-2,2,3,3-tetramethylcyclopropanes (2a--d) afforded rearranged products 1,2,3-butatrienes (3a-d) in good to high yields. Photorearrangement from 2,2,3-trimethyl and 2,2- and 2,3-dimethyl derivatives 2e--g also proceeded, but the rates of the rearrangement were lower than those of 2a--d. A singlet mechanism is proposed for this photorearrangement, where alkyl migration occurs from 1,3-biradical intermediates generated via the homolysis of the C1-C2 bond. Generation of diarylvinylidene carbenes from 1,3-biradicals might be competitive with the formation of 3.

Journal Article↗

Beneficial effect of Helicobacter pylori eradication in dermatologic diseases.

BACKGROUND: A relationship between skin diseases, particularly rosacea and chronic urticaria, and H. pylori infection has been suggested. METHODS: We preformed a prospective evaluation of the effect of H. pylori eradication in patients with a variety of chronic skin diseases. Patients were followed monthly for at least one year after cure of the infection. The effect of therapy was scored using a three point scale: complete remission (> 90% improvement), partial remission (50-90% improvement) or no improvement (< 50 improvement). The relationship between response and anti-H. pylori Ig G and E to specific H. pylori antigens was analyzed by Western blot analysis. RESULTS: Eighty-eight H. pylori-infected patients with skin disease were enrolled. Treatment was successful in 73% of patients with chronic urticaria as 23% (6 of 26) had complete and 50% had partial remission. Sixty-two percent (18 of 29) with pruritus cutaneus had partial remission as well as 30% with prurigo chronica multiformis had complete remission. Western blotting was done on 24 patients with skin disease and a 44K H. pylori antigen was detected by Ig E analysis in 100% (5 of 5) patients with complete remission compared to 23% (3 of 13) in those without skin disease. CONCLUSIONS: These results suggest it may be prudent to test patients with chronic urticaria, prurigo chronica multiformis, pruritus cutaneus, and eczema nummulare for H. pylori infection and to eradicate the infection in those whose test is positive.

Anti-Bacterial Agents↗

Duodenal erosions after eradication of Helicobacter pylori infection.

BACKGROUND: There is interest in the development of GERD after Helicobacter pylori eradication. In contrast, the development of duodenal erosions after therapy has received scant attention. Patients were examined after eradication of H pylori infection to determine the frequency of post-therapy duodenal erosions (primary outcome) and whether there was a relation between development of duodenal and esophageal erosions. Additionally, factors were searched for that would identify patients at increased risk for duodenal erosions. METHODS: A single-center, endoscopist-blinded, observational study was conducted of 196 patients in whom H pylori was eradicated. The presence of esophageal or duodenal erosions was evaluated 4 weeks and 6 months after eradication. Serum gastrin and pepsinogen I (PG I) and II (PG II) levels were also determined for 83 patients entering the study during its final year. RESULTS: Multiple small duodenal erosions developed in 8.6% of patients after H pylori eradication and were more common in patients with pre-eradication duodenal ulcer (27.8%) compared with those with gastric ulcer (6.7%) or atrophic gastritis (1.4%) (p < 0.05). Duodenal erosions were associated with high levels of PG I before and after eradication. The frequency of duodenal erosions decreased over time (3.1% by 6 months). CONCLUSION: Duodenal erosions occur after H pylori eradication and appear to be related to duodenal ulcer and increased PG I levels, both of which are associated with increased acid secretion. Measurement of PG I may help to identify patients who have duodenal erosions develop after H pylori therapy for studies of the pathogenesis of these lesions.

Duodenal Ulcer↗

Genomic structure of the human ING1 gene and tumor-specific mutations detected in head and neck squamous cell carcinomas.

We characterized the genomic structure of the human ING1 gene, a candidate tumor suppressor gene, and found that the gene has three exons. We also demonstrated that four mRNA variants were transcribed from three different promoter regions. Of 34 informative cases of head and neck squamous cell carcinoma, 68% of tumors showed loss of heterozygosity at chromosome 13q33-34, where the ING1 gene is located. Here we present the first report that three missense mutations and three silent changes were detected in the ING1 gene in 6 of 23 tumors with allelic loss at the 13q33-34 region. These missense mutations were found within the PHD finger domain and nuclear localization motif in ING1 protein, probably abrogating the normal function.

Carcinoma, Squamous Cell↗

Identification of mutagenic heterocyclic amines (IQ, Trp-P-1 and AalphaC) in the water of the Danube river.

Three mutagenic heterocyclic amines, 2-amino-3-methylimidazo-[4, 5-f]quinoline (IQ), 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole (Trp-P-1) and 2-amino-9H-pyrido[2,3-b]indole (AalphaC), were isolated and identified in water from the Danube River in Vienna. Heterocyclic amines were extracted from river water by the blue rayon hanging method, and analyzed by gas chromatography with a nitrogen-phosphorous detector (GC-NPD) and GC-mass spectrometry (GC-MS) after conversion into their N-dimethylaminomethylene derivatives. Identity of IQ, Trp-P-1 and AalphaC in the river water was confirmed by GC-MS. The contents of IQ, Trp-P-1 and AalphaC were estimated by GC-NPD at 1.78+/-0.17, 0.14+/-0.02 and 0.44+/-0.02 ng/g blue rayon equivalent (n=3), respectively. The total amounts of these amines accounted for 26% of the mutagenicity of blue rayon extracts evaluated by the Ames test using TA98 with metabolic activation.

Amines↗

Inhibitory neural pathway regulating gastric emptying in rats.

The relaxation of the pylorus is one of the most important factors for promoting gastric emptying. However, the role of inhibitory neurotransmitters in the regulation of pyloric relaxation and gastric emptying remains unclear. In this study, we investigated the effects of NO biosynthesis inhibitor, N(G)-nitro-L-arginine methyl ester (L-NAME), and calcium dependent potassium channel blocker, apamin, on vagal stimulation-induced pyloric relaxation and gastric emptying in rats. Sodium nitroprusside (SNP), adenosine 5'-triphosphate (ATP), vasoactive intestinal polypeptide (VIP) and pituitary adenylate cyclase-activating peptide (PACAP) caused pyloric relaxations in a dose dependent manner in vivo. Apamin (120 microg/kg) significantly reduced ATP and PACAP-induced pyloric relaxations without affecting SNP- or VIP-induced relaxations. Vagal stimulation (10 V, 1 ms, 1-20 Hz)-induced pyloric relaxation was significantly inhibited by L-NAME (10 mg/kg). The combined administration of L-NAME and apamin almost completely abolished vagal stimulation-induced pyloric relaxation. L-NAME and apamin significantly increased spontaneous contractions in the antrum, pylorus and duodenum. Increased motility index by L-NAME and apamin was significantly higher in the pylorus and duodenum, compared to that of antrum. L-NAME and apamin significantly delayed liquid gastric emptying. These results suggest that besides NO, probably ATP and PACAP, act as inhibitory neurotransmitters in the rat pylorus and regulate gastric emptying.

Adenosine Triphosphate↗

Helicobacter pylori infection reduces intraluminal nitric oxide.

BACKGROUND: Nitric oxide (NO) plays an important role in gastrointestinal mucosal protection. We have previously shown that Helicobacter pylori infection is associated with a lower concentration of NO in the human stomach. The aim of this study is to explore the pathogenesis of this finding using an animal model. METHODS: Mongolian gerbils were divided into four groups: H. pylori-negative and -positive, each with and without the intraperitoneal addition of superoxide dismutase (SOD). Intraluminal NO and serum nitrate were measured by using a chemiluminescence system. Inducible nitric oxide synthase (iNOS) levels in gastric mucosa were measured by using the NOSdetect Assay Kit. RESULTS: iNOS levels in H. pylori-positive gerbils were significantly greater than in those without infection. Intraluminal NO levels in H. pylori-positive gerbils were significantly lower than those in H. pylori-negative ones and increased after SOD administration. Serum nitrate levels in H. pylori-positive gerbils were significantly greater than those in H. pylori negative ones and decreased after SOD administration. CONCLUSIONS: The low level of NO in the gastric lumen in H. pylori infection is likely a result of superoxide production related to H. pylori-induced inflammation.

Animals↗

Helicobacter pylori infection reduces intraluminal nitric oxide in humans.

It has recently been demonstrated that nitric oxide (NO) is highly concentrated in the gastric lumen and plays an important role in defending against pathogenic microorganisms in the stomach. NO in the gastric lumen is mainly delivered by extrinsic sources from saliva. We studied whether Helicobacter pylori infection affected intraluminal NO levels in humans. H. pylori infection was diagnosed on the basis of histology and culture or (13C)-urea breath test. Air and gastric juice in the gastric lumen were collected endoscopically. The concentration of intraluminal NO was measured by a chemiluminescence system, using an NO analyzer. The concentration of nitrite in gastric juice was measured by the Griess reaction. The intraluminal concentration of NO in H. pylori-positive patients (198.2 +/- 41 parts per billion [ppb] mean +/- SE; n = 70) was significantly lower than that in H. pylori-negative patients (353.0 +/-57.9ppb; n = 43; P < 0.05). In contrast, the concentration of nitrite in gastric juice in H. pylori-positive patients (57.7 +/- 12.3 RM; n = 70) was significantly higher than that in H. pylori-negative patients (25.9 +/- 6.4 microM; n = 43, P < 0.01). The intraluminal concentration of NO in H. pylori-positive patients was markedly increased and the concentration of nitrite in H. pylori-positive patients was markedly decreased following the completion of eradication therapy. Based on these results, we propose that a decrease in NO and excess nitrite production in the gastric lumen are associated with H. pylori infection and may play an important role in the pathogenesis of H. pylori-related abnormalities.

Female↗

Hereditary angioedema with gastrointestinal involvement: endoscopic appearance.

We present the first reported case of hereditary angioedema (HAE) with gastric involvement to be successfully evaluated by endoscopy both during and after an attack. A 31-year-old man who had a family history of angioedema was admitted to our hospital with complaints of abdominal pain and swelling of extremities. Computed tomography scan and endoscopy carried out during this attack revealed transient gastrointestinal wall edema which, along with decreased levels of serum C4 and C1 inhibitor, confirmed the diagnosis of HAE with gastrointestinal involvement. During the attack, the gastric mucosa was erythematous and edematous, and parts of its surface bulged into the gastric lumen, resembling a submucosal tumor, as a result of massive submucosal edema. During the healing process, a number of small nodules and raised erosions developed over the entire gastric mucosal surface after healing of prominent gastric edema. Within 55 days, the gastric mucosa had returned to normal. The endoscopic findings for the stomach in HAE have not, to our knowledge, been previously described.

Adult↗

Comparison of tumor markers in patients with squamous cell carcinoma of the head and neck.

The serum concentrations of three separate tumor markers, squamous cell carcinoma antigen (SCC Ag), carcinoembryonic antigen (CEA) and Cyfra 21-1 were clinically correlated in 86 randomly selected patients with squamous cell carcinoma involving the head and neck. Positive findings for each tumor marker were totalled and statistically analysed. The upper limits of normal for SCC Ag, CEA and Cyfra 21-1 were set at 1.5, 2.5 and 2.0 ng/ml, respectively. Positivity rates were 20.6% for SCC Ag, 14.0% for CEA and 41.7% for Cyfra 21-1. Elevated Cyfra 21-1 concentrations correlated somewhat with age, whereas elevated CEA levels correlated with the site of tumor involvement. Overall, Cyfra 21-1 appeared to be the most useful marker in head and neck squamous cell carcinoma.

Aged↗

Screening for aetiology of thrombophilia: a high prevalence of protein S abnormality.

We systematically screened for the aetiology of thrombophilia in 115 patients with venous, arterial and small vessel thromboses. Forty-one patients (36% of those we examined) suffering from a variety of thromboses, including deep vein thrombosis, pulmonary embolism, arterial occlusion, cerebral infarction, Moyamoya disease and ulcerative colitis, were characterized either with positive lupus anticoagulants or with decreased activities of protein S, protein C, antithrombin III and/or plasminogen. Eight mutation sites were confirmed in 11 thrombotic patients using gene analysis. Decreased protein S activity was found with a high incidence (23 out of 115) in Japanese patients who suffered from not only venous thrombosis but also arterial and small vessel thrombosis. We emphasize here the important role of protein S in the pathogenesis of thrombosis in the Japanese population.

Adolescent↗

[Esophagitis, gastritis and duodenitis provoked by cure of Helicobacter pylori infection].

It has been recently reported that curing Helicobacter pylori (H. pylori) infection may provoke reflux esophagitis. We studied the effect of cure of H. pylori infection on the development of disorders of the upper gastrointestinal (UGI) tract. The estimated incidence of reflux esophagitis, gastric erosions and duodenal erosions after cure of infection was 8.9%, 32.8% and 8.9%. The incidences of reflux esophagitis, gastric erosions and duodenal erosions were 10.0%, 30.0% and 6.7% in patients with gastric ulcer, 2.8%, 36.1% and 27.8% in those with duodenal ulcer and 9.2%, 30.3% and 1.3% in those with atrophic gastritis. Therefore, patients whose H. pylori infection has been cured should carefully be investigated by endoscopy for H. pylori-associated disease.

Duodenitis↗

Human papillomavirus as a risk factor for head and neck cancers--a case-control study.

A retrospective, case-control study was conducted to examine the relationship between the presence of human papillomavirus types 16 and 18 (HPV16/18) DNA and the risk of head and neck cancers. Twelve out of 74 (16.2%) head and neck cancers contained HPV16/18 DNA, while 3 out of 70 (4.2%) non-cancer controls showed HPV16/18 positivity by polymerase chain reaction. The presence of HPV16/18 DNA was associated with an increased risk of head and neck cancer formation, showing an odds ratio of 4.32, with a 95% confidence interval of 1.26-14.78. Although its epidemiological impact might be smaller than that of other factors like cigarette smoking, the presence of HPV16/18 DNA in the aerodigestive tract is suggested to be a risk factor for human head and neck cancers.

Carcinoma, Squamous Cell↗

Fetal development of the pituitary gland in the beagle.

BACKGROUND: The pituitary gland of the dog is different from all animals and is described as "typical" for mammals. How might this complex pituitary gland of the dog be formed in fetal life? The current study examined the fetal development of the complex and unique dog pituitary and the ontogeny of specific cell types in the pars distalis. METHODS: Adenohypophysis of the beagle, from 25 to 60 days of gestation and at 2 days of age, was studied by immunocytochemical and histological staining. RESULTS: At 25 days gestation, the primordium (Rathke's pouch) of the adenohypophysis began to form by an upward evagination from the epithelium of the primary oral cavity. At 38 days, the pituitary gland showed the same morphology as in adult dogs, being merely smaller. Five walls of Rathke's pouch (anterior wall [A], lateral walls [L], posterior wall [P], and upper wall [U] were found at 25 days, and by 38 days they had specialized into specific regions of the adenohypophysis through complex and unique processes. The pars intermedia was derived from the U and the dorsal area of the A. The pars tuberalis was derived from the dorsal area of the A. The pars distalis was formed by more singular processes: the peripheral areas of the pars distalis were first formed by A and P; then the ventral lumen of the extensive Rathke's lumen surrounded by these areas was filled up by proliferation of cells, although the dorsal lumen remains as Rathke's lumen after 38 days. The blood capillaries may play an important role in the development of parencymal cells in the Rathke's pouch during canine fetal life. At 30 days gestation, the first adrenocorticotropic hormone cells were found in the anterior- and posterior-ventral regions (derived from middle and ventral areas of the A and the P) of the pars distalis anlage, and blood capillaries invaded the parenchymal cells from the mesencyme surrounding the anlage. At 38 days, portal vessels without capillary loops in the median eminence had appeared, and growth hormone and luteinizing hormone cells appeared in the ventral areas of A and P in the pars distalis. By 52 days, when capillary loops were seen in the portal vessels in the median eminence, these types of cells spread through the whole pars distalis. CONCLUSION: These areas in the epithelium of Rathke's pouch at 25 days may differentiate into specific regions of the pars distalis during subsequent fetal life, through complex processes that are characteristics to the canine species.

Adrenal Glands↗

Analysis of antigens targeted by circulating IgG and IgA autoantibodies in 50 patients with cicatricial pemphigoid.

In this study we investigated sera from 50 typical cicatricial pemphigoid (CP) patients. By indirect immunofluorescence on 1 M NaCl-split human skin sections, IgG of 17 sera and IgA of 22 sera reacted with the epidermal side of the split, while IgG of two sera reacted with the dermal side. These latter two sera were later confirmed to be anti-epiligrin CP. By immunoblotting of epidermal extracts, IgG of 14 sera reacted with the 230 kD bullous pemphigoid (BP) antigen (BP230). IgG of 15 sera and IgA of 11 sera reacted with the 180 kD BP antigen (BP180). Interestingly, a bacterial fusion protein containing the BP180 NC16a domain was recognized by IgG of 18 sera but not by IgA of any sera. Fusion proteins containing the C-terminal region of BP180 were recognized by IgG of 20 sera, but it was detected by IgA of only two sera. Our results suggest that, although CP sera show very low titers of autoantibodies, a considerable number of sera contain IgG antibodies to BP180 (either NC16a or C-terminal domain), confirming previous studies. In addition, we showed that greater numbers of IgA antibodies react with BP180, seemingly with different types of epitopes from those for IgG antibodies. Because the specificity of IgG antibodies is not very different from those in BP, IgA antibodies may play a specific role for the development of characteristic clinical features in CP. Future studies should elucidate the pathogenic role of the IgA antibodies in CP.

Animals↗