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Biomedical subjects

H Shishido

Publications and source records attributed to H Shishido.

At least 19 recordsLinked to original sources

Giant Nernst effect in CeCoIn5.

We present a study of Nernst and Seebeck coefficients of the heavy-fermion superconductor CeCoIn5. Below 18 K, concomitant with a field-dependent Seebeck coefficient, a large sublinear Nernst signal emerges with a magnitude drastically exceeding what is expected for a multiband Fermi-liquid metal. In the mixed state, in contrast with all other superconductors studied before, this signal overwhelms the one associated with the motion of superconducting vortices. The results point to a hitherto unknown source of transverse thermoelectricity in strongly interacting electrons.

Journal Article↗

Comparative study on the use of solid media: Löwenstein-Jensen and Ogawa in the determination of anti-tuberculosis drug susceptibility.

A total of 53 Mycobacterium tuberculosis strains were examined to evaluate the consistency of susceptibility tests using two solid egg-based culture media, Ogawa and Löwenstein-Jensen (L-J), in order to assess the inter-media differences in susceptibility tests for anti-tuberculosis drugs. Fifty-three M. tuberculosis strains were tested for resistance against isoniazid, rifampicin, ethambutol, streptomycin and other alternative drugs on L-J and Ogawa media. Data from isoniazid (INH) revealed 31 strains were susceptible and 11 strains were resistant in L-J medium. On the other hand, one strain showed resistance against INH only on Ogawa medium. This gave a consistency ratio of 97.7% for INH between these two media. Similarly, the methods had 100% compatibility with rifampicin, 86.0% with ethambutol and 88.4% with streptomycin. When 41 of these strains were tested against ethionamide, enviomycin, para -aminosalicylate, sparfloxacin, and levofloxacin, the same numbers of strains were shown to be resistant or susceptible to L-J and Ogawa media. Similarly, the consistency ratio was 75.6% for kanamycin and 61.0% for capreomycin. There are inconsistencies between results obtained with L-J and Ogawa media, Ogawa medium had a tendency to produce results that indicated more resistant strains. However, the differences were statistically negligible.

Antitubercular Agents↗

Angular position of nodes in the superconducting gap of quasi-2D heavy-fermion superconductor CeCoIn5.

The thermal conductivity of the heavy-fermion superconductor CeCoIn5 has been studied in a magnetic field rotating within the 2D planes. A clear fourfold symmetry of the thermal conductivity which is characteristic of a superconducting gap with nodes along the ( +/- pi,+/- pi) directions is resolved. The thermal conductivity measurement also reveals a first-order transition at H(c2), indicating a Pauli limited superconducting state. These results indicate that the symmetry most likely belongs to d(x(2)-y(2)), implying that the anisotropic antiferromagnetic fluctuation is relevant to the superconductivity.

Journal Article↗

Potential use of Amplicor PCR kit in diagnosing pulmonary tuberculosis from gastric aspirate.

Polymerase chain reaction (PCR) detection of mycobacteria from gastric aspirate for the diagnosis of tuberculosis is not fully evaluated up to now. A total of 116 gastric aspirate specimens were collected from patients with suspected pulmonary tuberculosis. The breakdown of diagnosis was 67 pulmonary tuberculosis, 16 nontuberculous mycobacterial infection, 5 extra pulmonary tuberculosis, and 28 other lung diseases. The conventional methods were shown to have a sensitivity of 47.8% and a specificity of 79.6%; on the other hand, Amplicor had 34.9% and 97.0%, respectively. The Amplicor provided a more rapid and specific method for diagnosing tuberculosis and was more useful than the conventional.

Adult↗

Clinical evaluation of Amplicor Mycobacterium detection system for the diagnosis of pulmonary mycobacterial infection using sputum.

SETTING: The Amplicor Mycobacterium detection kit was evaluated for the diagnosis of active pulmonary mycobacterial infection using sputum. OBJECTIVE: To assess the clinical usefulness of the Amplicor Mycobacterium kit for the diagnosis of pulmonary tuberculosis and non-tuberculous mycobacterial infection in the country of medium prevalence. DESIGN: All the patients were diagnosed with bacterial, histopathological, and clinical 'gold standard'. The sensitivity and specificity for diagnosing clinically active pulmonary tuberculosis and Mycobacterium avium and Mycobacterium intracellulare infections were evaluated comparing Amplicor results and clinical diagnosis. RESULTS: A total of 1088 sputum specimens were collected from 780 in and out patients. Mycobacteria were recovered from 339 specimens by culture. The sensitivity and specificity of conventional culture method for the diagnosis of pulmonary tuberculosis were 60.2% and 99.8% respectively based on the number of patients. The figures for Amplicor were 61.8% and 97.4% respectively. There was no statistical significant difference between these methods. In rapidity, the Amplicor was significantly superior to the microscopy method in sensitivity. CONCLUSION: Patients with Amplicor positive and conventional negative result had mostly mycobacteria related diseases. The Amplicor positive result indicated mostly active mycobacterial infection and was clinically useful for rapid diagnosis.

Chi-Square Distribution↗

Endoscopic recurrence of esophageal varices is associated with the specific EUS abnormalities: severe periesophageal collateral veins and large perforating veins.

BACKGROUND: Endoscopic ultrasonography (EUS) with a 20 MHz ultrasound (US) catheter probe can clearly demonstrate esophageal collateral veins. The presence of large periesophageal collateral veins has been correlated with large esophageal varices in patients with portal hypertension. The correlation between the size of esophageal collateral veins and endoscopic recurrence of esophageal varices in patients with portal hypertension who had undergone endoscopic injection sclerotherapy was investigated. Furthermore, whether EUS findings could predict the variceal recurrence was retrospectively studied. METHODS: Thirty-eight patients who had undergone endoscopic injection sclerotherapy were examined every 3 to 4 months with endoscopy and US catheter probe for a period of 2 years. Recurrence of esophageal varices was determined by endoscopic findings of either new varix formation or appearance of red color sign. Esophageal collateral veins were identified by US catheter probe as peri-esophageal collateral veins (adjacent to the esophageal wall) and para-esophageal collateral veins (separated from the esophageal wall) along with perforating veins; and they were graded as severe and mild type by US catheter probe. RESULT: Ten of the 38 patients (26.3%) had endoscopic recurrence at a mean of 10.9 months after endoscopic injection sclerotherapy. In patients with endoscopic recurrences, EUS findings included a significantly (p < 0.001) higher incidence of severe type peri-esophageal collateral veins, a significantly larger number of perforating veins (p < 0.001) and a significantly larger diameter of perforating veins (p < 0.001) compared with patients without recurrence (8 of 10, 80% vs. 2 of 28, 7.1%; 1.30 vs. 0.21; 2.00 vs. 0.32 mm, respectively). The presence of veins at the esophagogastric junction did not correlate with recurrence. CONCLUSION: Severe type peri-esophageal collateral veins and large perforating veins of the esophagus detected by EUS in patients treated by endoscopic injection sclerotherapy signify recurrence of esophageal varices and predict endoscopic recurrence of varices in subsequent months.

Collateral Circulation↗

Protein-losing enteropathy exacerbated with the appearance of symptoms of systemic lupus erythematosus.

A 38-year-old woman visited our hospital with edema on her face and conjunctivae. The underlying disease was not clarified, and she did not visit the hospital afterwards. She suffered from diarrhea, polyarthralgia, Raynaud's phenomenon, malar rash and hair loss in the subsequent two years, and was hospitalized because of hypoproteinemia. Her urine, liver and heart test results did not account for her hypoproteinemia. She was diagnosed as having protein-losing enteropathy (PLE) associated with SLE based on the 99mtechnetium-labeled human serum albumin scintigraphy findings, clinical findings and laboratory results of antinuclear and anti-Sm antibodies. This case report demonstrates a strong association between PLE and SLE because PLE was aggravated along with the appearance of SLE symptoms and PLE subsided with prednisolone treatment along with improvement of SLE.

Adult↗

Amebiasis in Japanese homosexual men with human immunodeficiency virus infection.

We report cases of amebiasis in 6 human immunodeficiency virus (HIV)-positive male patients. Five were confirmed homosexuals while one was suspected. Three patients had liver abscess and 5 had colitis with duration of 10 days to months. The patients with liver abscess showed a lower incidence of abdominal pain but a higher incidence of concomitant diarrhea. Drainage therapy was effective for rapid afebrile results. Two invasive colitis cases died from perforation. This may have been due to delayed diagnosis. Invasive amebiasis is not common even in HIV-infected individuals. Among Japanese homosexual men, however, it may cause symptomatic diseases.

AIDS-Related Opportunistic Infections↗

Usefulness of endoscopic ultrasonographic analysis of variceal hemodynamics for the treatment of esophageal varices.

The correlation of between the endoscopic findings of esophageal varices and endoscopic ultrasound findings of the collaterals outside the esophageal wall in patients with portal hypertension remains unclear. We investigated the relationship between esophageal varices and the collaterals by endoscopy and endoscopic ultrasound. Moreover, we investigated the correlation between the collaterals around the esophagus and recurrence of esophageal varices in patients with portal hypertension who had undergone endoscopic injection sclerotherapy. The collaterals were divided into two groups: 1; those with peri-esophageal collateral veins (peri-ECVs) adjacent to the muscularis externa of the esophagus, and 2; those with para-esophageal collateral veins (para-ECVs) distal to the esophageal wall without contact with the muscularis externa. Peri- and para-ECVs were scored as mild or severe according to the stage of development. According to endoscopy, the varix form was significantly larger in severe peri-ECVs group than in mild peri-ECVs group. In contrast, the varix form did not differ significantly between the mild and severe para-ECVs group. The prevalence of perforating veins increased according to the varix form. With regard to variceal recurrence, in patients with variceal recurrences, EUS findings included a significantly higher incidence of severe-type peri-ECVs, a significantly larger number of perforating veins, and a significantly larger diameter of perforating veins compared with patients without recurrence. Moreover, when EUS found the abnormalities when no endoscopic recurrence was found, the results were the almost same as the findings when EUS was performed at the same time when endoscopic recurrence was found. In conclusion, the presence of severe peri-ECVs and large perforating veins in the esophageal wall strongly correlates with occurrence and recurrence of esophageal varices in patients with portal hypertension. An understanding of these EUS abnormalities on the basis of hemodynamics around the esophagus is thought to be important for management of esophageal varices in patients with portal hypertension.

Collateral Circulation↗

Injection of plasmid DNA into the gastric mucosa induces mucosal and systemic immunity.

Nearly all mucosal surfaces participate in a common mucosal immune system, and application of an antigen to one mucosal surface elicits local as well as distant mucosal immune responses. However, whether the gastric mucosa is a part of this network has not been examined directly. We show here that the injection of plasmid DNA encoding beta-galactosidase into the gastric wall caused transfection of gastric mucosal epithelial cells, induced systemic and mucosal antibody responses at both local (digestive tract) and distant (genital and respiratory tracts) sites, and induced cytotoxic T lymphocyte responses in the spleen and the mesenteric and iliac lymph nodes.

Animals↗

Primary antiphospholipid syndrome presenting with cerebral ischemia, thrombocytopenia, anemia and proteinuria successfully treated with warfarin potassium.

A 30-year-old woman with primary antiphospholipid syndrome (PAPS) presented with cerebral ischemia, thrombocytopenia, anemia and proteinuria. Administration of warfarin potassium, without concomitant corticosteroid administration, significantly improved all of these symptoms along with a decrease in the titers of antiCL-beta2-GP-I antibodies and a shortening of prolonged APTT. Therefore, the antiphospholipid antibodies in this patient could have been evoked by vitamin-K-dependent coagulation factors or plasma proteins which are assumed to undergo conformational changes exposing cryptic epitopes. This case report provides clues to the mechanisms underlying the production of antiphospholipid antibodies in patients with PAPS.

Adult↗

Comparative study of amplicor Mycobacterium PCR and conventional methods for the diagnosis of pleuritis caused by mycobacterial infection.

OBJECTIVE: To assess the clinical significance of the Amplicor Mycobacterium system for the diagnosis of mycobacterial infection in patients with pleural fluid, and to compare its usefulness with that of conventional smear and culture methods. DESIGN: Pleural fluid specimens were obtained randomly from in-patients admitted to National Tokyo Hospital between January and December 1996. All the patients were diagnosed with bacterial, histopathological and clinical gold standard. The sensitivity and specificity for diagnosis of mycobacterial infection were evaluated. RESULTS: Seventy-five pleural fluid specimens were obtained. Conventional methods demonstrated a sensitivity of 30.6% and a specificity of 100%, while the Amplicor Mycobacterium demonstrated a sensitivity and specificity of 27.3% and 97.6% respectively. Lactic dehydrogenase, carcinoembryonic antigen, red blood cell, protein, glucose and types of inflammatory cells were not different in Amplicor positive and negative pleural fluid with mycobacterial infection. CONCLUSION: There was not much improvement in the accuracy of diagnosis when Amplicor Mycobacterium was used to diagnose mycobacterial pleuritis among various diseases with pleural fluid; however, the assay time was dramatically reduced with the use of Amplicor Mycobacterium.

Bacteriological Techniques↗

Adjuvant effect of a 14-member macrolide antibiotic on DNA vaccine.

Macrolide antibiotics have unique immunomodulatory actions apart from their antimicrobial properties. We examined the effect of erythromycin (EM), a 14-member macrolide, on the immune response to a DNA vaccine that induces a T-helper-1 (Th1)-biased immune response through a Th1-promoting adjuvant effect of unmethylated CpG motifs within plasmid DNA. EM enhanced Th1 responses in plasmid DNA-immunized mice as measured by antigen-specific IgG2a antibody production, interferon-gamma production by antigen-specific CD4(+) T cells, and cytotoxic T lymphocyte responses. EM augmented the accessory cell activity of unmethylated CpG DNA-stimulated antigen-presenting cells (APCs), suggesting that EM enhances Th1 responses to a DNA vaccine, possibly through augmentation of accessory cell activity of APCs stimulated with CpG motifs within plasmid DNA.

Adjuvants, Immunologic↗

EUS analysis of collateral veins inside and outside the esophageal wall in portal hypertension.

BACKGROUND: The relation between esophageal varices and venous collaterals outside the esophageal wall in patients with portal hypertension remains unclear. We investigated this relationship with endoscopy and endoscopic ultrasound (US). METHODS: Twenty-two patients with untreated varices were examined. The collaterals were studied with a 20 MHz US catheter probe. Collaterals were divided into two groups: (1) periesophageal collateral veins adjacent to the muscularis externa of the esophagus and (2) paraesophageal collateral veins external to the esophageal wall but without contact with the muscularis externa. Periesophageal and paraesophageal collateral veins were scored as mild or severe according to stage of development. RESULTS: Varix form as defined endoscopically was significantly larger in the severe periesophageal collateral veins group than in the mild periesophageal collateral veins group (p < 0. 01). In contrast, varix form did not differ significantly between the mild and severe paraesophageal collateral veins groups. Perforating veins were detected in the distal esophagus in 18 of 22 patients (81.8%) by means of US. The prevalence of perforating veins increased in relation to varix form. Two types of perforating veins were found on the basis of connection with periesophageal and paraesophageal collateral veins. The frequency with which perforating veins were connected to periesophageal collateral veins was 81.8%; the frequency of connection to paraesophageal collateral veins was 27.3%. CONCLUSION: Periesophageal collateral veins play a more important role in the formation of esophageal varices than do paraesophageal collateral veins.

Adult↗

[Evaluation of CO2 condition for antibiotic susceptibility test of Helicobacter pylori on microdilution broth].

We determined the MICs of clarithromycin for 32 Helicobacter pylori strains isolated from gastric mucosa of patients, by using microdilution broth method under different microaerobic conditions (CO2: 5% and 15%). The pH of broth was more acidic at 15% CO2 than that of at 5% CO2. The MICs of clarithromycin for all H. pylori strains at 15% CO2 condition were higher than that of clarithromycin at 5% CO2 condition. Comparing the MICs with the results of eradication therapy, we concluded that the measurement of MIC under 5%CO2 condition is more useful for expecting the clinical outcome.

Carbon Dioxide↗

Effect of granulocyte-colony stimulating factor on empiric therapy with flomoxef sodium and tobramycin in febrile neutropenic patients with hematological malignancies. Kan-etsu Hematological Disease and Infection Study Group.

The clinical effects of concomitant use of granulocyte-colony stimulating factor (G-CSF) on empiric antibiotic therapy in febrile neutropenic patients were evaluated in a randomized fashion. Two hundred and fourteen neutropenic febrile episodes (neutrophil counts < 1.0 x 10(9)/l) were treated with flomoxef sodium and tobramycin with or without G-CSF. The resolution of fever at day 4 (excellent response) or at day 7 (good response) was deemed effective. Among 157 evaluable episodes, the observed excellent responses were 31 (38.8%) and the good responses were 20 (25.0%) in the G-CSF group; those in the control group were 26 (33.8%) and 25 (32.5%), respectively. The overall efficacy rate was 63.8% (51/80) in the G-CSF group and 66.2% (51/77) in the control group (not significant). The initial neutrophil count was 0.186 +/- 0.249 x 10(9)/l in the G-CSF group and 0.235 +/- 0.290 x 10(9)/l in the control group, and rose to 2.889 +/- 4.198 x 10(9)/l and 0.522 +/- 0.844 x 10(9)/l, respectively, at day 7. These results indicate that G-CSF does not affect the rate of response to empiric antibiotic therapy in febrile neutropenic patients, although a significant effect of G-CSF was observed on neutrophil recovery.

Adolescent↗

Rhabdomyolysis and aggravation of arthritis in a rheumatoid arthritis patient as a result of sepsis due to Staphylococcus aureus infection of a rheumatoid nodule; a catastrophic outcome.

A 63-year-old man with rheumatoid arthritis presented with rhabdomyolysis and intractable arthritis of acute onset. He was diagnosed to have sepsis due to Staphylococcus aureus infection through of an ulcerated rheumatoid nodule. Staphylococcus aureus isolated from pus in the ulcerated rheumatoid nodule and a blood sample obtained from the heart post-mortem produced the toxic shock syndrome toxin-1 (TSST-1). The TSST-1 and/or unmethylated CpG motifs in the oligonucleotides present in a bacterium, Staphylococcus aureus in this case, might be implicated in the induction of rhabdomyolysis and intractable arthritis.

Arthritis, Rheumatoid↗