Search PubMed⌕ Search

Biomedical subjects

Shigeru Kohno

Publications and source records attributed to Shigeru Kohno.

At least 253 records · Page 14Linked to original sources

Antisense oligonucleotides against collagen-binding stress protein HSP47 suppress peritoneal fibrosis in rats.

BACKGROUND: Peritoneal fibrosis is a serious complication in patients on continuous ambulatory peritoneal dialysis (CAPD), but the molecular mechanism of this process remains unclear. Heat shock protein 47 (HSP47), a collagen-specific molecular chaperone, is essential for biosynthesis and secretion of collagen molecules, and is expressed in the tissue of human peritoneal fibrosis. In the present study, we examined the effect of HSP47 antisense oligonucleotides (ODNs) on the development of experimental peritoneal fibrosis induced by daily intraperitoneal injections of chlorhexidine gluconate (CG). METHODS: HSP47 antisense or sense ODNs were injected simultaneously with CG from day 14, after injections of CG alone. Peritoneal tissue was dissected out 28 days after CG injection. The expression patterns of HSP47, type I and type III collagen, alpha-smooth muscle actin (alpha-SMA), as a marker of myofibroblasts, ED-1 (as a marker of macrophages), and factor VIII were examined by immunohistochemistry. RESULTS: In rats treated with CG alone, the submesothelial collagenous compact zone was thickened, where the expression levels of HSP47, type I and type III collagen and alpha-SMA were increased. Marked macrophage infiltration was also noted and the number of vessels positively stained for factor VIII increased in the CG-treated group. Treatment with antisense ODNs, but not sense ODNs, abrogated CG-induced changes in the expression of HSP47, type I and III collagen, alpha-SMA, and the number of infiltrating macrophages and vessels. CONCLUSION: Our results indicate the involvement of HSP47 in the progression of peritoneal fibrosis and that inhibition of HSP47 expression might merit further clinical investigation for the treatment of peritoneal fibrosis in CAPD patients.

Actins↗

Lafutidine, a novel histamine H2-receptor antagonist, vs lansoprazole in combination with amoxicillin and clarithromycin for eradication of Helicobacter pylori.

BACKGROUND: In contrast to the growing amount of data concerning proton pump inhibitor-based triple therapy for Helicobacter pylori infection, it is still controversial whether proton pump inhibitor can be replaced by H2 receptor antagonist without compromising efficacy. Lafutidine is a novel potent H2 receptor antagonist with gastroprotective activities such as enhancement of gastric mucosal blood flow. METHODS: 122 outpatients with positive cultures and subsequent successful cultivation of H. pylori for antimicrobial susceptibility tests were randomized to receive a 7-day course of either lafutidine (20 mg twice daily) or lansoprazole (30 mg twice daily), plus clarithromycin (200 mg twice daily) and amoxicillin (750 mg twice daily). Eradication was considered successful if the rapid urease test, culture, histology and [13]C-urea breath test were all negative at least 4 weeks after cessation of therapy. Cytochrome p450 2C19 genotype status using polymerase chain reaction-restriction fragment length polymorphism was also studied. RESULTS: On intention-to-treat basis, H. pylori cure was achieved in 52 of 61 (85.2%) patients and 49 of 61 (80.3%) patients for the lafutidine- and lansoprazole-based therapies, respectively. The predicted 95% confidential intervals for the 4.9% of the difference were -1.8-11.6%. Using per protocol analysis, the eradication rates were 88.2% (52/59) and 84.5% (49/58), respectively. The predicted 95% confidential intervals for the 3.7% of the difference were -2.6-10.0%. Adverse events were observed in five and six patients, from the lafutidine and lansoprazole groups, respectively, but they were generally mild. Genetic predisposition of cytochrome p450 2C19 had no significant influence on treatment outcome in both regimens. CONCLUSIONS: The lafutidine-clarithromycin-amoxicillin therapy yielded satisfactory results for eradicating H. pylori, which was comparable with those of the lansoprazole-based regimen with the same drug combination.

2-Pyridinylmethylsulfinylbenzimidazoles↗

Cysteinyl leukotrienes induce nuclear factor kappa b activation and RANTES production in a murine model of asthma.

BACKGROUND: It has been demonstrated that both cysteinyl leukotrienes (cysLTs) and cytokines are involved in the pathophysiology of bronchial asthma. Nonetheless, the exact mechanism involved in the interaction between these 2 molecules has yet to be determined. OBJECTIVE: The aim of the present study was to determine the effects of cysLTs on allergic airway inflammation and allergen-specific cytokine production in a murine model of asthma. METHODS: Four groups of BALB/c mice (control mice, Dermatophagoides farinae allergen-sensitized mice, pranlukast cysLT receptor antagonist-treated allergen-sensitized mice, and dexamethasone-treated allergen-sensitized mice) were examined. RESULTS: Allergen-sensitized mice exhibited increased airway responsiveness and inflammation. Pranlukast-treated mice showed significant attenuation of these changes concomitant with reduction of T(H)2 cytokine and IFN-gamma production by isolated lung mononuclear cells (MNCs). A much stronger inhibition of all cytokines was noted in dexamethasone-treated mice. Pranlukast also significantly inhibited production of RANTES and activation of nuclear factor kappa B (NF-kappa B) in the isolated lung MNCs. Leukotriene D(4) stimulated isolated lung MNCs to produce RANTES but not any other cytokines and also activated NF-kappa B in these cells. CONCLUSIONS: Our results suggest that cysLTs activate NF-kappa B and induce RANTES production from isolated lung MNCs, which in turn might cause migration of eosinophils and activated T lymphocytes into the airway.

Animals↗

Anti-extractable nuclear antigens (ENA) antibodies in patients with chronic hepatitis C before and after treatment with interferon.

A high prevalence of serological markers classically associated with autoimmune hepatitis or other autoimmune diseases has been reported in patients with chronic hepatitis C. However, the prevalence of antibodies to extractable nuclear antigens (anti-ENA) are rarely reported in such patients and the effect of treatment with interferon (IFN) on their prevalence is not known. In the present study, serum samples collected from 44 patients with chronic hepatitis C and 44 patients with non-hepatitis C virus (HCV) infected liver diseases were tested for anti-ENAs (U1 RNP, Sm, Ro/SS-A, La/SS-B and Scl-70) antibodies by enzyme-linked immunosorbent assay (ELISA). In 26 patients with chronic hepatitis C who received IFN treatment, serum samples were also collected just after completion of IFN treatment, and/or at 6-40 months after completion of the treatment, and tested for these antibodies. Sixteen (36%) of 44 sera from patients with chronic hepatitis C were positive for at least one of the above anti-ENA antibodies, whereas only 7 (16%) of 44 sera from patients with non-HCV infected liver diseases were positive for such antibodies (p = 0.0290). There was no significant difference in the prevalence of each of anti-ENA antibody between men and women. Results of anti-ENA antibodies in most IFN-treated patients with chronic hepatitis C did not change after treatment. However, in some cases serum anti-U1 RNP, anti-La/SS-B and anti-Scl-70 became negative or converted to the gray zone after completion of IFN treatment regardless of HCV elimination. Our results showed that the overall prevalence of anti-ENA antibodies was significantly higher in patients with chronic hepatitis C than in those with non-HCV-infected liver diseases. However, the disappearance of anti-ENA antibodies after IFN treatment in patients with chronic hepatitis C may be due to the immunomodulating effects of IFN rather than HCV elimination.

Adult↗

Two cases of adult T-cell leukemia/lymphoma involving the terminal ileum.

We describe two cases of adult T-cell leukemia/lymphoma (ATLL) with terminal ileal involvement. The first case, a 71-year-old man with lymphoma subtype of ATLL, had a polypoid lesion in the terminal ileum, in addition to a duodenal mass. The second case, a 58-year-old woman with lymphoma subtype of ATLL, had an irregular ulcerative lesion in the terminal ileum and multiple ulcers throughout the stomach. Biopsies from these lesions revealed mucosal invasion of ATLL cells in each case. In the second case, combination chemotherapy was transiently effective, resulting in the disappearance of gastric and terminal ileal lesions. Prospective and careful examination of additional cases should further characterize the clinicopathological features of terminal ileal involvement in ATLL.

Aged↗

Successful treatment with cyclosporin in adult-onset Still disease manifesting as acute hepatitis with marked hyperferritinemia.

A 48-year-old woman was admitted because of spiking high fever, sore throat, and jaundice. A diagnosis was made of adult-onset Still disease (AOSD) presenting with acute hepatitis and very high serum ferritin levels (32,240 ng/mL), and she was treated with 2 courses of pulse therapy of methylprednisolone (2 g/day for 3 days) followed by 40 mg/day prednisolone. Subsequently, the serum level of ferritin decreased, but serum total bilirubin increased to 17.3 mg/dL. Therefore, cyclosporin was administered orally. Within the next 3 months, results of liver function tests, as well as serum levels of ferritin, soluble interleukin-2 receptor, interferon-gamma, interleukin-6, and tumor necrosis factor-alpha gradually returned to within normal limits, and cyclosporin administration was subsequently reduced gradually. The clinical presentation suggests that AOSD should be considered when liver dysfunction is accompanied with high fever and extreme hyperferritinemia, and that treatment with cyclosporin or other immunosuppressive drugs that selectively suppress cytokine production by helper T cells is a valuable option in the treatment of AOSD with very high serum ferritin levels.

Administration, Oral↗

A case of mucosa-associated lymphoid tissue lymphoma of the ampulla of Vater: successful treatment with radiation therapy.

Mucosa-associated lymphoid tissue (MALT) lymphoma of the papilla of Vater is rare, and little is known of either its association with Helicobacter pylori infection or the optimal treatment modalities. We describe the first case of MALT lymphoma involving the major papilla that remained unchanged despite eradication of H. pylori, but which regressed following radiotherapy. A 46-year-old asymptomatic man was admitted to hospital for treatment of MALT lymphoma involving the papilla of Vater. Duodenal endoscopy showed multiple granules around the major ampulla, and biopsies revealed mucosal proliferation of centrocyte-like cells, lymphoepithelial lesions, hyperplastic lymphoid follicles and plasmacytic differentiation. The lymphoma cells were positive for B-cell but negative for T-cell markers, and expressed Bcl-2 but showed no immunoreactivity for CD5, CD10 and cyclin D, consistent with MALT lymphoma. The patient was successfully treated with triple therapy of lansoprazole, amoxicillin and clarithromycin for 1 week for coexisting H. pylori infection in the stomach, but the lymphoma lesions remained unchanged. Then, involved-field irradiation was applied at a total dose of 30 Gy delivered in 1.5 Gy fractions without any adverse events. Six months later, repeat endoscopy revealed disappearance of the granular lesions and lack of lymphoma cells in biopsy specimens. Four years after the commencement of radiotherapy, the patient is still in complete remission. Radiotherapy seems a safe and effective treatment modality for low-grade MALT lymphoma of the ampulla of Vater.

Ampulla of Vater↗

Role of elastase in a mouse model of chronic respiratory Pseudomonas aeruginosa infection that mimics diffuse panbronchiolitis.

Pseudomonas aeruginosa frequently colonizes the respiratory tract of patients suffering from cystic fibrosis (CF) and diffuse panbronchiolitis (DPB). However, the relationship between lung inflammation and extracellular products of P. aeruginosa is not well-defined. To assess the role of elastase released by P. aeruginosa in DPB, a murine model of DPB was employed in this study. Mice were inoculated with either P. aeruginosa PAO1 or PAO-E64; the latter produces elastase with greatly reduced enzymic activity. Throughout the 90-day experiments, counts of viable bacteria from the PAO1- and PAO-E64-infected mice were found to be equivalent. However, the number of lymphocytes isolated from the lungs of PAO-E64-infected mice was significantly lower than the number isolated from the lungs of PAO1-infected animals. Histopathological examination of the lungs of mice infected by PAO1 on day 90 revealed an intense accumulation of chronic respiratory cells surrounding the bronchi, in sharp contrast to the more localized inflammatory response found in those mice infected by PAO-E64. These data suggest that P. aeruginosa elastase (PE) is a potent inflammatory factor in a mouse model of DPB and that the control of PE release by P. aeruginosa may be beneficial for patients with DPB.

Animals↗

Elevated levels of chemokines in esophageal mucosa of patients with reflux esophagitis.

OBJECTIVE: Chemokines play a key role in the pathogenesis of various inflammatory conditions. However, there is little information on their profile in reflux esophagitis (RE). We sought to study esophageal mucosa levels of chemokines in RE. METHODS: A total of 32 outpatients with RE and 13 normal controls were studied. Endoscopic severity of RE was classified according to the Los Angeles grading system. Paired biopsy specimens were taken from the esophagus 3 cm above the gastroesophageal junction; one biopsy was snap frozen for measurement of mucosal levels of interleukin 8 (IL-8), monocyte chemoattractant protein 1 (MCP-1), regulated on activation normal T-cell expressed and presumably secreted (RANTES), and IL-1 beta by enzyme linked immunosorbent assays, while the other was formalin-fixed for histopathological evaluation. RESULTS: IL-8, MCP-1, and RANTES levels were significantly higher in esophageal mucosa of RE patients than those of the controls. IL-8 levels correlated significantly with the endoscopic severity of RE. Basal zone hyperplasia and papillary elongation, histopathological hallmarks of RE, were both associated with higher levels of IL-8 and MCP-1. The presence of intraepithelial neutrophils and eosinophils, which also indicate RE, was associated with high levels of IL-8 and RANTES, respectively. There were no significant differences in IL-1 beta levels between the RE and control groups, but IL-1 beta levels correlated significantly with the IL-8 production. Again, the IL-8 levels were significantly decreased after lansoprazole treatment. CONCLUSION: Our results indicate that chemokines produced locally in the esophageal mucosa may be involved in the development and progression of RE.

Adult↗

[Analysis of tuberculin skin test in employees of Nagasaki University Hospital].

The tuberculin skin test (TST) was conducted in 1,087 employees of Nagasaki University Hospital. The size of erythema (T1) was 27.3 +/- 17.0 mm, and 8.6% of all participants showed < = 9 mm, 49.9% showed 10-29 mm, 41.5% showed > = 30 mm. Laboratory technologists showed significantly larger reactions than other groups. Doctors and nurses working on the tuberculosis ward showed larger reactions than those working on the non-tuberculosis wards. Reactions tended to be larger with aging, and the younger employees in their 20s showed significantly smaller reactions than those in their 40s. The second TST was carried out in 253 employees whose T1 was below 30 mm. The size of erythema enlarged from 16.1 +/- 6.6 mm (T1) to 26.4 +/- 15.4 mm (T2), with the difference (booster phenomenon) of 10.2 +/- 14.4 mm. T2 and T2-T1 were larger in nurses working on the tuberculosis ward than those on the non-tuberculosis wards. It was suggested that laboratory technologists, nurses and doctors especially working on the tuberculosis ward are at risk of tuberculosis infection, and the two-step TST was an essential means to know the baseline reactivity, and to determine recent tuberculosis infection.

Adult↗

[Successful treatment with linezolid in two cases of methicillin-resistant Staphylococcus aureus infections in the orthopedic field].

We have reported two orthopedic patients with Methicillin-resistant Staphylococcus aureus (MRSA) infections successfully treated with linezolid. The first case was a 64-years-old man with bacteremia, spondylitis and psoas abscesses caused by MRSA. He was treated with arbekacin (ABK) and vancomycin (VCM), and then became afebrile. However he complained of a recurrence of fever and oliguria, we administered linezolid for two weeks intravenously because of fluctuating renal dysfunction. Thereafter his clinical conditions improved. The second case was a 26-years-old man with MRSA infection of the pelvis after a trauma. He was treated with teicoplanin (TEIC) for two weeks. However the minimum inhibiratory concentrations (MICs) of TEIC and VCM against MRSA, isolated from the wounds, were 4 micrograms/ml each, we administered linezolid intravenously and the patient was successfully treated in four weeks. Linezolid has been proven to have high efficacy against MRSA by some trials abroad. But the agent has the indication only for VRE by the Medical Insurance in Japan. These cases also suggest that linezolid is useful for MRSA infections in these cases.

Acetamides↗

Effects of DQ-113, a new quinolone, against methicillin- and vancomycin-resistant Staphylococcus aureus-caused hematogenous pulmonary infections in mice.

We compared the effects of DQ-113, a new quinolone, to those of vancomycin (VCM) and teicoplanin (TEIC) in murine models of hematogenous pulmonary infections caused by methicillin-resistant Staphylococcus aureus (MRSA) and VCM-insensitive S. aureus (VISA). The MICs of DQ-113, VCM, and TEIC for MRSA were 0.125, 1.0, and 0.5 microg/ml, respectively; and those for VISA were 0.25, 8.0, and 8.0 microg/ml, respectively. Treatment with DQ-113 resulted in a significant decrease in the number of viable bacteria in the lungs of the mice used in the MRSA infection model (counts in mice treated with DQ-113, VCM, and TEIC and control mice, 6.33 +/- 0.22, 7.99 +/- 0.14, 7.36 +/- 0.20, and 8.47 +/- 0.22 log10 CFU/lung [mean +/- standard error of the mean], respectively [P<0.01 for the group treated with DQ-113 compared with the group treated with VCM or TEIC or the untreated group]). Mice infected with VISA were pretreated with cyclophosphamide, and the survival rate was recorded daily for 10 days. At the end of this period, 90% of the DQ-113-treated mice were still alive, whereas only 45 to 55% of the mice in the other three groups were still alive (P<0.05 for the group treated with DQ-113 compared with the group treated with VCM or TEIC or the untreated group]). DQ-113 also significantly (P<0.05) reduced the number of viable bacteria in the lungs compared with those in the lungs of the other three groups (counts in mice treated with DQ-113, VCM, and TEIC and control mice, 5.76 +/- 0.39, 7.33 +/- 0.07, 6.90 +/- 0.21, and 7.44 +/- 0.17 log10 CFU/lung, respectively). Histopathological examination revealed milder inflammatory changes in DQ-113-treated mice than in the mice in the other groups. Of the antibiotics analyzed, the parameters of area under the concentration-time from 0 to 6 h (AUC(0-6))/MIC and the time that the AUC(0-6) exceeded the MIC were the highest for DQ-113. Our results suggest that DQ-113 is potent and effective for the treatment of hematogenous pulmonary infections caused by MRSA and VISA strains.

Animals↗

In vivo efficacy of a new quinolone, DQ-113, against Streptococcus pneumoniae in a mouse model.

DQ-113 is a new quinolone with potent activity against gram-positive pathogens. The in vivo activity of DQ-113 against Streptococcus pneumoniae was compared with those of gatifloxacin and ciprofloxacin in a mouse model. For this purpose, two strains of S. pneumoniae were used: penicillin-susceptible S. pneumoniae (PSSP) and penicillin-resistant S. pneumoniae (PRSP). The survival rates of mice infected with PSSP and PRSP at 14 days after infection were 80% in the DQ-113-treated group and 0 to 10% in the other three groups. In murine infections caused by PSSP, the 50% effective doses (ED50s) of DQ-113, gatifloxacin, and ciprofloxacin were 6.0, 41.3, and 131.6 mg/kg, respectively. Against PRSP-caused pneumonia in mice, the ED50s of DQ-113, gatifloxacin, and ciprofloxacin were 7.6, 64.7, and 125.9 mg/kg, respectively. Compared with the other drugs, DQ-113 showed excellent therapeutic efficacy and eradicated viable bacteria in both PSSP- and PRSP-infected mice. The means +/- standard errors of the means of viable bacterium counts in the lungs of gatifloxacin-treated, ciprofloxacin-treated, and untreated control mice infected with PSSP were 2.91 +/- 0.34, 3.13 +/- 0.48, and 3.86 +/- 0.80 log10 CFU/ml, respectively. The same counts in mice infected with PRSP treated with the same three agents were 6.57 +/- 0.99, 6.54 +/- 0.40, and 7.17 +/- 0.43 log10 CFU/ml, respectively. DQ-113 significantly decreased the number of viable bacteria in the lungs compared with gatifloxacin and ciprofloxacin. Of the drugs analyzed, the pharmacokinetic-pharmacodynamic parameter of area under the concentration-time curve (AUC)/MIC ratio for DQ-113 was significantly higher than those for gatifloxacin and ciprofloxacin. Our results suggest that DQ-113 has potent in vivo efficacy against both PSSP and PRSP.

Animals↗