Biomedical subjects

A Shiotani

Publications and source records attributed to A Shiotani.

At least 19 recordsLinked to original sources

PubMed2002

Association between gastric myoelectrical activity and intraluminal nitric oxide.

BACKGROUND: We have previously shown that the intraluminal concentration of NO in H. pylori-positive patients is significantly reduced compared to that in H. pylori-negative patients. AIM: The aim of this study was to evaluate the effect of H. pylori infection on gastric motor activity in relation to the level of NO and nitrite in the stomach in humans. METHODS: Thirty-two H. pylori-negative and 32 H. pylori-positive patients with dyspepsia were studied. Gastric myoelectrical activity was recorded for 24 h using surface electrogastrography. Intraluminal gas and juice were endoscopically collected from the stomach to determine NO and nitrite and nitrate (NOx) levels using a chemiluminescence system. RESULTS: The percentage of tachygastria in the morning preprandial state was significantly higher (P = 0.005) in H. pylori-positive than -negative patients. In H. pylori-negative patients, there was a significant positive correlation between NO levels and the percentage of bradygastria (r = 0.56, P = 0.001) and a significant negative correlation between NOx levels and the percentage of normal electrical activity (r = - 0.57, P=0.001) in the preprandial state. CONCLUSIONS: Gastric motor activity is associated with NO and NOx levels in the gastric lumen. H. pylori infection may play a role in the pathogenesis of abnormal gastric myoelectrical activity.

Adolescent↗

PubMed2001

Study of movements of individual structures of the larynx during swallowing.

OBJECTIVE: The purpose of this study was to reveal movements of individual structures of the larynx during swallowing. METHODS: Subjects were 7 healthy adults, aged 24 to 32 years (average 27 years), who had no organic or functional disease of the pharynx and larynx and 2 adults with unilateral recurrent nerve palsy, aged 49 and 60 years, respectively. We used the Toshiba IIDR system, which is composed of an X-ray TV system and a digital image managing circuit. One-fifth diluted Omnipark 300 was used as contrast medium (lohexol), with 15 cc for each swallow. The mask image for subtraction was designated as the frame before laryngeal elevation during swallowing for subtraction. We obtained the images for observation and analysis after subtracting the mask image from continuously obtained images. These images were captured into a personal computer at 30 frames per s and thereafter frame-by-frame observation and analysis were performed by means of NIH image 1.56. RESULTS: We observed that the vocal folds underwent a series of movements during swallowing. (1) They adduct slowly and do not ascend; (2) then begin to ascend and continue adducting; whereby (3) they abduct for a moment while ascending. (4) Again, they adduct and achieve closure. (5) While maintaining closure, vocal folds elevate further to reach their maximal elevation; and (6) begin to abduct rapidly while maintaining maximal elevation. Finally, (7) they begin to descend and undergo repeated irregular abduction and adduction while descending. In examining the relationship between closure and opening at levels of the vocal fold and false vocal fold, we found that closure at the false vocal fold level precedes that at the vocal fold level and that opening at the vocal fold level precedes that at the level of the false vocal fold. CONCLUSION: Closure of the false vocal fold level appears important in the protection of the lower respiratory tract during swallowing.

Adult↗

PubMed2001

Skeletal muscle regeneration after insulin-like growth factor I gene transfer by recombinant Sendai virus vector.

We scrutinized the applicability and efficacy of Sendai virus (SeV) vectors expressing either LacZ or human insulin-like growth factor-I (hIGF-I) in gene transfer into skeletal muscle. Seven days after the intramuscular injection of LacZ/SeV X-gal labeled myofibers were demonstrated in rat anterior tibialis muscle with/without bupivacaine treatment and the transgene expression persisted up to 1 month after injection. Recombinant hIGF-I was detected as a major protein species in culture supernatants of a neonatal rat myoblast cell line L6 and thus induced the cells to undergo myogenetic differentiation. The introduction of hIGF-I/SeV into the muscle showed a significant increase in regenerating and split myofibers which were indicative of hypertrophy, and also an increase in the total number of myofibers, in comparison to that seen in the LacZ/SeV-treated control muscle. These results demonstrate that SeV achieves high-level transgene expression in skeletal muscle, and that hIGF-I gene transfer using SeV vector may therefore have great potential in the treatment of neuromuscular disorders.

Animals↗

PubMed2001

Citric acid-enhanced Helicobacter pylori urease activity in vivo is unrelated to gastric emptying.

BACKGROUND: In a previous study, the use of a citric acid test meal produced a rapid dose-dependent increase in urease activity that was significantly greater than that resulting from a pudding meal, ascorbic acid or sodium citrate. The mechanism was hypothesized to be related to the ability of citric acid to delay gastric emptying and possibly to enhance intragastric distribution of the urea. OBJECTIVE: To compare the effects of sodium citrate, two doses of citric acid and a pudding meal on gastric motor function. METHOD: Eleven normal healthy volunteers were investigated using non-invasive techniques to measure gastric emptying and gastric motility. We evaluated gastric emptying using the Meretek 13Ceebiscuit solid phase gastric emptying breath test, which employs a 340-calorie biscuit containing 200 mg of the edible 13C-blue-green alga Spirulina platensis, after the administration of test meals of pudding, 2 g and 4 g of citric acid and 2 g of sodium citrate. Electrogastrograms (Digitrapper EGG) were also recorded for 30 min before and 180 min after the test meal. RESULTS: Gastric emptying, as assessed by the half-time (T1/2), was delayed similarly with the pudding (136.8 +/- 9 min) and with 4 g of citric acid (144.5 +/- 7 min) (P > 0.7). Sodium citrate (108.7 +/- 6 min) and 2 g of citric acid (110.1 +/- 6 min) had similar effects on gastric emptying (P=0.986), and were significantly less effective in delaying gastric emptying (P < 0.01) compared to pudding or 4 g of citric acid. The electrogastrograms remained normal and there were no differences among meals and no relation with the gastric emptying results. CONCLUSIONS: The increased intragastric urea hydrolysis associated with citric acid test meals cannot be attributed to delayed gastric emptying. Changes in the intragastric distribution of urea or a direct effect of citric acid on the bacteria (e.g. via the cytoplasmic protein, UreI) are more likely to be responsible.

Adolescent↗

PubMed2001

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↗

PubMed2001

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↗

PubMed2001

Analysis of vocal fold vibration by x-ray stroboscopy with multiple markers.

OBJECTIVE: To derive a more precise description of vocal fold vibration, experimental phonation of excised canine larynxes was studied. STUDY DESIGN AND SETTING: Multiple X-ray-positive markers were inserted, and their vibratory movement was observed with x-ray stroboscopy with change of pitch and intensity. A histologic study was also carried out. RESULT: Regular waves were observed just above the lowest point of the lamina propria of the mucous membrane, which shifted upward at high pitch, but downward in high intensity. CONCLUSIONS: The starting point of the mucosal wave was confirmed on the lower surface of the vocal fold, histologically just above the lowest point of the lamina propria of the mucous membrane and shifted upward at high pitch, but downward in high intensity. SIGNIFICANCE: This is the first study investigating the starting point of mucosal wave in vocal fold vibration in a frontal plane using x-ray stroboscopy, providing the evidence for the body-cover theory.

Animals↗

PubMed2001

Localization of receptor activator of NFkappaB ligand, RANKL, in periodontal tissues during experimental movement of rat molars.

The receptor activator of NFkappaB ligand, RANKL, is one of the key regulatory molecules in osteoclast formation and function. We examined RANKL localization in the periodontal tissues during experimental movement of rat molars. To produce orthodontic force, an elastic band was inserted between the upper first and second molars for 4 days, and the dissected maxillae were subjected to light and electron microscopic immunocytochemical examination for RANKL. Expression of RANKL protein was detected in osteoblasts, osteocytes, fibroblasts, and osteoclasts mostly located in resorption lacunae. In osteoblasts, osteocytes, and fibroblasts, RANKL localization was mainly observed in the cytoplasm, the cisternae of rough endoplasmic reticulum and along plasma membranes. In osteoclasts, RANKL was expressed along the ruffled, border membranes and in the cytoplasm, including the clear zone. These results suggest that during tooth movement, osteoclast differentiation and activation are regulated, at least in part, by RANKL, possibly produced by osteoblasts/stromal cells and osteoclasts themselves in the periodontal tissues.

Animals↗

PubMed2001

Modulation of myosin heavy chains in rat laryngeal muscle.

OBJECTIVES: To test the hypothesis that myosin heavy chain (MHC) composition is a biological marker indicative of appropriate and functional reinnervation. STUDY DESIGN: Age-matched adult rats were randomized for prospective study under three experimental conditions. METHODS: In adult rats, three experimental conditions were surgically created, including transient recurrent laryngeal nerve (RLN) crush injury, RLN transection and repair, and cricoarytenoid joint fixation with intact RLN. Animals were survived for 30, 90, and 180 days. At each interval, vocal fold mobility was assessed by rigid microlaryngoscopy. Laryngeal electromyography (EMG) was performed before euthanasia. The thyroarytenoid and posterior cricoarytenoid muscles were then excised, each muscle was processed for sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and MHC composition was determined. RESULTS: Thirty days after nerve crush injury, three of six animals regained vocal fold mobility and normal MHC composition. Impaired vocal fold motion in three of six animals was associated with MHC composition characteristic of denervation. At 90 and 180 days, normal vocal fold motion and normal MHC composition were observed in all animals. Following nerve transection and repair, impaired vocal fold motion and MHC composition characteristic of denervation were observed in all animals, despite evidence of reinnervation on EMG. Following joint fixation, alteration in MHC composition consistent with denervation was observed only at 30 days, as was evident in the nerve crush model. CONCLUSION: Temporary injury and vocal fold immobilization result in transient shifts in MHC composition. Nerve transection and repair result in persistent alteration of MHC composition and vocal fold dysfunction. The expression of normal MHC composition is dependent on the condition of appropriate neural contact and functional reinnervation.

Animals↗

PubMed2000

Helicobacter pylori.

H. pylori infection is now recognized as causing serious and life threatening disease in 20% to 30% of those infected. Reliable therapy is problematic. This article addresses the current approach to diagnosis and therapy and new considerations regarding whom to treat. The emphasis of the association of the gastric cancer phenotype of H. pylori infection (cagA positive H. pylori corpus gastritis) and protection against gastroesophageal reflux disease is an example of epidemiology without regard to the biology. Improvements in health and diet and an increase in body mass have accompanied the natural loss of H. pylori from the population. The search for virulence factors to help direct therapy to those who would most benefit has, to date, proved fruitless. Whenever H. pylori is diagnosed, it should be treated.

Anti-Bacterial Agents↗

PubMed2000

Obesity-sleep apnea (Pickwickian) syndrome: autopsy findings and a medicolegal review.

A 24-year-old obese woman was found dead in her boyfriend's apartment in his absence. She had been admitted to the hospital six times previously because of diminished consciousness, respiratory failure, and pneumonia. A diagnosis of obesity-sleep apnea (Pickwickian) syndrome was made. An autopsy showed that she had an extremely small larynx, intra-alveolar hemorrhage, edema, pulmonary lymphocyte infiltration, and severe focal myocardial fibrosis. No fresh myocardial lesion, coronary arterial lesion, or findings of heart failure were seen. The woman's elder sister had also died of the same disease at the age of 23. The cause of death was diagnosed as respiratory failure and pneumonia with the sleep-apnea syndrome as the underlying cause of death. Although no autopsy reports of the sleep-apnea syndrome have been published in the field of forensic pathology, this syndrome is a predominant cause of sudden death in obese persons and could be a hidden cause of accidental death in such persons.

Journal Article↗

PubMed2000

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↗

PubMed1999

IGF-1 gene transfer into denervated rat laryngeal muscle.

OBJECTIVES: To demonstrate gene transfer in rat laryngeal muscle using a reporter gene, beta-galactosidase, and a muscle-specific expression system containing the human IGF-1 (hIGF-1) gene sequence and to investigate the myotrophic and neurotrophic effects of hIGF-1 gene transfer in denervated rat laryngeal muscle. METHODS: In 8 adult rats, a polyvinyl-based formulation containing beta-galactosidase DNA was injected into denervated thyroarytenoid muscle. Twelve animals were similarly administered a polyvinyl-based formulation containing a muscle-specific expression system and hIGF-1 DNA. Twelve animals were injected with isotonic sodium chloride solution, and all animals survived for 1 month. The production of beta-galactosidase and hIGF-1 was detected using immunohistochemical techniques. The effects of hIGF-1 on motor endplates and nerve sprouting were assessed using cholinesterase or silver staining and immunostaining for growth-associated protein (GAP-43). mals by immunostaining, X-gal histochemical staining, or both. In frozen section specimens, hIGF-1 immunoreactivity was positive in 3 of 8 animals. In sequential sections, GAP-43 was localized to areas of hIGF-1 expression in 2 of the 3 hIGF-1-positive specimens. Increased nerve sprouting and motor endplate contact occurred in 2 of 4 animals treated with hIGF-1. CONCLUSIONS: Gene transfer into laryngeal muscle was demonstrated using a polyvinyl-based formulation containing a muscle-specific gene expression system. Preliminary findings indicate a positive effect on motor endplates, nerve sprouting, and the expression of GAP-43 in animals treated with the hIGF-1 vector. This study establishes a foundation for investigating hIGF-1 gene transfer as a novel treatment of laryngeal paralysis. Further studies are necessary to quantify myotrophic and neurotrophic effects and to establish therapeutic benefit.

Animals↗

PubMed1999

Human insulinlike growth factor 1 gene transfer into paralyzed rat larynx: single vs multiple injection.

OBJECTIVE: To compare the biological effects of single vs multiple treatment of rat denervated laryngeal muscle with human insulinlike growth factor 1 (hIGF1) gene therapy. EXPERIMENTAL METHODS OR DESIGN: A muscle-specific nonviral vector containing the alpha-actin promoter and hIGF1 gene formulated with polyvinyl polymers was injected into denervated adult rat thyroarytenoid muscle. The effects on animals given a single injection (n = 16) vs those given multiple injections (n = 14) vs control groups (n = 18) were evaluated. Twenty-eight days after the first injection, gene expression, muscle fiber size, motor endplate length, and nerve-to-motor endplate contact were evaluated. RESULTS: Gene expression, detected by reverse transcriptase polymerase chain reaction for hIGF1 messenger RNA, occurred in 13 (81%) of 16 animals receiving single injections and 14 (100%) of 14 animals receiving multiple injections. Compared with controls, hIGF1-transfected animals in both single- and multiple-injection groups had a significant increase in the lesser diameter of muscle fiber, a significant decrease in motor endplate length, and a significant increase in the percentage of endplates with nerve contact (P <.05 for all). There was no statistical difference between single- and multiple-injection groups. CONCLUSIONS: Applied to laryngeal paralysis, hIGF1 gene therapy provides an opportunity to augment surgical treatment modalities by the prevention or reversal of muscle atrophy, and enhancement of nerve sprouting and muscle reinnervation. Although the percentage of denervated muscles demonstrating hIGF1 expression was increased following multiple injections, no difference was observed in the biological response compared with that in the single-injection treatment groups. Further investigation will be conducted to assess long-term benefits and physiological responses and to define the limitations of this potentially valuable therapeutic strategy.

Animals↗

PubMed1999

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↗

PubMed1999

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↗

PubMed1999

Myosin heavy chain composition in human laryngeal muscles.

OBJECTIVES: Myosin heavy chain (MHC) composition of human thyroarytenoid (TA), lateral cricoarytenoid (LCA), interarytenoid (IA), vocalis, posterior cricoarytenoid (PCA), and cricothyroid muscles were examined using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and Western bolt techniques. The presence of superfast MHC was also assessed using antibodies directed against the extraocular MHC. STUDY DESIGN: MHC protein was analyzed using fresh human laryngeal muscles. METHODS: Laryngeal muscles excised from cadavers were processed for SDS-PAGE. The composition of MHC isoforms was determined by densitometry. Western blot was carried out to identify specific bands. RESULTS: MHC types IIA and IIB are the predominant MHC components in human laryngeal muscles. The adductor muscles--TA, LCA, and IA--have a higher percentage of type IIB MHC and a lower percentage of type I when compared with the abductor--PCA. The rank file order for type IIB MHC composition (TA > LCA > or = IA > PCA) is the same in all specimens. A band migrating between type IIA and type I was observed in several specimens. Although similar to type IIL in rats, this atypical band did not react with anti-extraocular MHC antibody on Western blot. CONCLUSION: Characterization of laryngeal muscles determined by the composition of MHC is correlated with function and neural input. Human laryngeal muscle is characterized by a predominance of fast-type MHCs in laryngeal closing muscle and mixed fast-slow type MHCs in respiratory and phonatory muscle groups. Although an atypical myosin band similar to type IIL (superfast) MHC in rat was identified, it did not react with anti-extraocular MHC antibody.

Aged↗

PubMed1999

Postnatal development of myosin heavy chain isoforms in rat laryngeal muscles.

The developmental transitions of myosin heavy chain (MHC) isoforms of rat posterior cricoarytenoid (PCA), thyroarytenoid (TA), cricothyroid (CT), and lateral cricoarytenoid (LCA) muscles were examined by means of sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and Western blot techniques. The muscles were microscopically dissected from animals on postnatal days 0, 3, 7, 10, 14, 21, 28, 35, 45, and 55 and from adult animals. Silver-stained SDS-PAGE gels of each muscle were analyzed densitometrically to measure the composition of MHC isoforms, and Western blot was carried out to identify specific bands. Characterizations of the internal laryngeal muscles determined by the composition of MHCs were correlated with their function in the adult. Temporally, differentiation reflects onset of function. Differentiation of isoforms and transition to adult forms occur first in the TA muscle, followed by the PCA, LCA, and CT muscles. Expression of type IIL was observed only in muscles innervated by the recurrent laryngeal nerve. Postnatally observed developmental differences of myosin phenotypes suggest that regulation of MHC expression is influenced by neural activity or other environmental factors.

Aging↗