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Biomedical subjects

S Hashimoto

Publications and source records attributed to S Hashimoto.

At least 217 records · Page 12Linked to original sources

Connexin expression in the salivary glands.

To investigate the ultrastructure of gap junctions and functional differences between connexin (gap junction structural protein) 32 and 43 in the rat submandibular and sublingual glands, tracer and freeze-fracture methods were carried out, and the expression of both connexins was examined. In both glands, western blot analysis with anti-connexin 32 and 43 antibodies revealed bands of about 27kD and 43kD, respectively. Immunofluorescence showed the presence of connexin32-positive spots between acinar cells in both glands. In contrast, connexin43-positive spots were observed at the periphery of the acinar structures in either gland. Positive spots for both connexins could not be detected between ductal cells in both glands. By immunocytochemistry, connexin32 was found on the gap junctional membranes of acinar cells and connexin43 on the gap junctional membranes of myoepithelial cells. It is surmised that connexin32 of the gap junction is related to the secretory function of acinar cells and that connexin43 is associated with the contraction of the myoepithelial cells.

Animals

Phenotypic change and proliferation of murine Kupffer cells by colony-stimulating factors.

Kupffer cells were isolated from C57BL/6 mice by collagenase perfusion and assessed for response to colony-stimulating factors (CSFs) in terms of their phenotypic change and proliferation. Kupffer cells expressed F4/80, but not Mac-1, CD71, or asialo-GM1 initially. This phenotype pattern was different from that of alveolar and peritoneal macrophages. After stimulation with recombinant human macrophage CSF (M-CSF) or mouse granulocyte-macrophage CSF (GM-CSF), Kupffer cells expressed Mac-1 and a low level of CD71 in addition to F4/80 and increased in phagocytotic activity in association with the expression of CR3. Both M-CSF and GM-CSF, but not human IL-3, induced the proliferation of Kupffer cells in a dose-dependent manner, and after 7 days, the number of the cells increased to about four to six times the initial number. The relatively high dose of GM-CSF downmodulated the M-CSF receptor on Kupffer cells and inhibited the cell proliferation induced by the optimal dose of M-CSF. These data indicated that murine Kupffer cells have a different phenotype from other macrophages and that they respond to M-CSF and GM-CSF, leading to functional maturation and proliferation.

Animals

Aerosolization of imipenem/cilastatin prevents pseudomonas-induced acute lung injury.

Aerosolization of imipenem/cilastatin was compared with continuous intravenous infusions of the antibiotic for pharmacokinetic/pharmacodynamic analysis. The concentrations of imipenim/cilastatin in bronchoalveolar lavage fluids (BAL) obtained from rats exposed to the aerosolized antibiotic were significantly greater than the concentrations in BAL in the rats that had received intravenous infusions of imipenem/cilastatin. The two methods of antibiotic delivery were compared for their effects on bacterial-induced lung injury in rats that had Pseudomonas aeruginosa instilled into their airspaces. The aerosolization of antibiotic was associated with significantly decreased bacterial-induced lung injury. The high concentrations of antibiotic in the airspaces secondary to aerosolization appears to kill bacteria more quickly and preserve lung epithelial and endothelial integrity better than systemic delivery of the same antibiotic.

Administration, Inhalation

Clear cell odontogenic carcinoma in the mandible: histochemical and immunohistochemical observations with a review of the literature.

A rare case of clear cell odontogenic carcinoma was investigated using histochemical and immunohistochemical methods. The tumor occurred in the anterior mandible of a 69-year-old Japanese man. Histologically, the tumor was composed mostly of large clear cells and squamous cells. Columnar-shaped cells with basophilic nuclei polarized away from the basement membrane were observed at the periphery of the tumor foci. The tumor cells had aggressively invaded muscle and perineural tissues. The tumor cells were positive for PAS staining. Immunohistochemically, tumor cells reacted positively to keratin, cytokeratin19, epithelial membrane antigen, and S-100 protein. The tumor was diagnosed as a clear cell odontogenic carcinoma. Its characteristics are discussed in term of its histopathological, histochemical and immunohistochemical features.

Aged

[Bacteriological studies of travellar's diarrhoea. 5) Analysis of enteropathogenic bacteria at Osaka Airport Quarantine Station from January 1992 through September 3rd, 1994].

During the last 2 years and 8 months before the closure of Osaka Airport Quarantine Station (from Jan. 1992 to Sep. 3, 1994), a total of 7,421,909 overseas travellers were quarantined. 15,919 reported themselves of suffering from diarrhoea. Bacteriological examination of a total of 6,031 individuals' stools were performed. 1) Various enteropathogenic bacteria were isolated from 31.2% of the stools examined. Isolated species were as follows: Plesiomonas shigelloides, 1,127 cases (59.9%); Vibrio parahaemolyticus, 293 cases (15.6%); Salmonella spp., 262 cases (13.9%); Shigella spp., 235 cases (12.5%); Aeromonas sobria, 93 cases (4.9%); V. cholerae non-O1, 69 cases (3.7%). 2) The enteropathogenic bacteria were isolated through out the year without any seasonal variation. 3) The major regions where the travellers were infected with the pathogens are as follows: V. cholerae non-O1 (NAG Vibrio) and enteropathogenic Escherichia coli, South-East and South-West Asia; Vibrio other than NAG, South-East and East Asia; Shigella, widely distributed but especially in India; P. shigelloides and Salmonella, widely distributed. 4) 2 strains of toxigenic (cholera toxin-producing) V. cholerae O139 were isolated from patients who had visited Indonesia and Thailand, respectively. 5) In 320 cases (17%), plural enteropathogenic bacteria were isolated from single patients, suggesting a high frequency of the mixed infections. 6) Among Shigella strains, S. sonnei were isolated the most, followed by S. flexneri (24.7%), S. boydii (8.8%) and S. dysenteriae (2.9%). 7) Among Salmonella serovers, Salmonella Enteritidis was isolated the most frequently (39 cases, 14.1%). 8) 218 (91.6%) of 238 Shigella strains and 103 (37.6%) of 276 Salmonella strains were resistant to one or more drugs tested (SM.CP.TC.KM.ABPC.NA.OFLX). 9) All of the 22 V. cholerae O1 strains were Ogawa, E1 Tor. Among them, 19 were toxigenic strains and 3 were non-toxigenic. 10) O4:K8 was the most frequently isolated serover of V. paraemolyticus. 87.4% of all V. parahaemolyticus strains were positive with thermostable direct hemolysin (TDH) gene, and 12.6% of them were positive with TDH-related hemolysin (TRH) gene by DNA-probe methods.

Diarrhea

Exotoxin A stimulates fluid reabsorption from distal airspaces of lung in anesthetized rats.

To determine whether exotoxin A may affect the transport of fluid across the lung epithelium, two isogenic strains of Pseudomonas aeruginosa PA103 (10(8) colony-forming units), one (PA103 tox omega) with a structural gene mutation in exotoxin A, were instilled into the distal airspaces of anesthetized rats. PA103 parental strain, but not its mutant, stimulated the removal of fluid from the distal airspaces of the lung. Instillation of exotoxin A alone caused a dose-dependent increase in the fluid transport across the lung epithelium. Instillation of amiloride (10(-3) M) with exotoxin A demonstrated that this effect partially depended on increased uptake of sodium across the lung epithelium. The absence of stimulation after instillation of an exotoxin A mutant (PE delta Glu553) without ADP-ribosyltransferase activity demonstrated that the effect of exotoxin A depended on its ADP-ribosyltransferase activity. Finally, the instillation of exotoxin A in rats depleted of macrophages indicated that the effect of exotoxin A was not secondary to the activation of alveolar macrophages by this toxin. In conclusion, these results indicate that the in vivo release of exotoxin A by live airspace P. aeruginosa directly stimulates the fluid removal from the airspaces by the lung epithelium. This may alter the volume or composition of airway secretions, and may contribute to the lung disease in patients infected with P. aeruginosa.

ADP Ribose Transferases

Depletion of alveolar macrophages decreases neutrophil chemotaxis to Pseudomonas airspace infections.

The mechanism for neutrophil (PMN) influx into infected airspaces of the lung is not known. To determine whether alveolar macrophage products are important in the initiation of chemotaxis, we depleted rats of alveolar macrophages by aerosolizing negatively charged oligolamellar liposomes complexed to clodronate disodium. Ninety-five percent of the alveolar macrophages were depleted, and lung injury and inflammation were minimized with this depletion technique. Rats depleted of alveolar macrophages were then anesthetized, and either 5 x 10(6) colony-forming units (CFU) or 5 x 10(7) CFU of Pseudomonas aeruginosa were instilled into the airspaces of these animals. When recombinant macrophage inflammatory protein MIP-2 was intratracheally instilled into rats depleted of alveolar macrophages, PMN were recruited to their airspaces. Nonetheless, PMN numbers were decreased in the lavage fluids when moderate or large inoculums of bacteria were instilled into depleted rats, although the PMN response appeared dose dependent. Levels of bioactive tumor necrosis factor-alpha and immunoreactive proteins CINC/gro (cytokine-induced PMN chemoattractant) in the lavage fluids obtained from infected rats depleted of alveolar macrophages were significantly decreased compared with the levels in the lavage fluids obtained from normal infected rats. MIP-2 mRNA expression, as detected by Northern analysis, was also decreased in the infected lungs of depleted rats, and the lavage fluid from these rats had significantly decreased chemotactic activity. Therefore these results suggest that alveolar macrophage products play a direct role in the initial recruitment of PMN into infected lungs.

Animals

Melatonin rhythm is not shifted by lights that suppress nocturnal melatonin in humans under entrainment.

Effects of a single light exposure on the circadian rhythm in plasma melatonin were, examined in young males to obtain the threshold of light intensity for suppressing the nocturnal melatonin level on the one hand and to understand the relationship between the light-induced phase shift of melatonin rhythm and the melatonin suppression on the other hand. Eight subjects spent 3 days in an experimental living facility where light intensity was set below 200 lx and were exposed to light for 3 h in the early morning on the 2nd day. The same procedure was repeated five times in each subject with an interval of at least 3 wk, and one of five light intensities was tested in each trial. As a result, nocturnal melatonin level was not suppressed by light of 200 lx but significantly suppressed by light of intensity > or + 500 lx. On the other hand, the circadian melatonin rhythm was not shifted by any light intensity up to 10,000 lx. It is concluded that the threshold of light intensity for suppressing the melatonin level is located between 200 and 500 lx in young Japanese males, and the threshold for phase shifting the circadian melatonin rhythm was much greater than that for suppressing the nocturnal melatonin level in humans under entrained conditions.

Adult

Functional disturbance of naive T lymphocytes in very high IgE producers: depletion of interleukin-4-induced interleukin-4-producing cells.

We examined the capacity of T cells from normal individuals and allergic patients with very high IgE to differentiate into interleukin-4(IL-4)-producing cells in vitro. T cells incubated with anti-CD3 monoclonal antibody plus IL-4 or plus anti-IL-4 antibody in the presence of antigen-presenting cells for 7 days were restimulated and their capacity to express IL-4 mRNA was examined by RT-PCR. In T cells from normal individuals, there was a marked increase in the expression of IL-4 mRNA following the addition of IL-4. After fractionation of normal T cells into naive T (CD45RA+) and memory T (CD45RO+) cells, induction of the increase of IL-4 mRNA was restricted to the naive T cell population. In contrast, in T cells from allergic patients, the stimulation of whole or naive T cells with anti-CD 3 monoclonal antibody in the presence of IL-4 induced much less IL-4 mRNA. These findings suggest the presence of a functional abnormality in IL-4-dependent development of IL-4-producing T cells in the peripheral-blood naive T cells from allergic patients.

Adjuvants, Immunologic

Peripheral blood T lymphocytes and basophils, freshly isolated from house-dust-mite-sensitive patients, produce interleukin-4 in response to allergen-specific stimulation.

We examined the capacity of interleukin-4 (IL) production from lymphocytes and basophils, isolated from the peripheral blood of allergic patients sensitive to house dust mite, after stimulation with mite extract. IL-4 production was measured by a sensitive bioassay based on coculture with CT.h4S (a human IL-4-responsive cell line). Lymphocytes and basophils from patients with elevated serum IgE specific to mite allergen [radioallergosorbent test (RAST) score > 3] could produce detectable levels of IL-4 in response to mite extract, whereas those from patients with a RAST score of less than 2 or normal volunteers could not. The sensitivity of basophils to mite extract was high, so that a lower concentration of mite extract (1-10 ng/ml) could induce maximal IL-4 production. On the other hand, a higher concentration (10 micrograms/ml) was required for maximal IL-4 production from the lymphocytes. These findings demonstrate that allergen-specific IL-4-producing cells, lymphocytes and basophils, are generated in vivo in allergic patients and also that there exist characteristic differences between lymphocytes and basophils related to the in vivo source of IL-4.

Allergens

Monkey Clara cell 10 kDa protein (CC10): a characterization of the amino acid sequence with an evolutional comparison with humans, rabbits, rats, and mice.

Monkey Clara cell 10 kDa protein (CC10) was purified from monkey lung lavage. This protein showed an apparent molecular weight of about 10 kDa and 5 kDa under non-reducing and reducing conditions, respectively, as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. From the amino acid sequence data, monkey CC10 protein consisted of two identical 70-amino-acid polypeptide chains joined by two cystine residues, and possessed sequence identities of 78.6%, 52.9%, 52.9%, and 44.3% with human CC10, rat CC10 (PCB binding protein), rabbit uteroglobin, and mouse CC10, respectively. When monkey CC10 was compared with rabbit uteroglobin (progesterone binding protein), two polar residues of Tyr-21 and Thr-60, important for progesterone binding specificity, were substituted for Phe-21 and Met-60, and thus monkey CC10 may not have a binding capacity with progesterone. Monkey CC10 also possessed a surface homology with lipocortin I (anti-inflammatory peptide), thus suggesting that monkey CC10 plays a role in the anti-inflammatory process at the air-liquid interface over the bronchio-bronchiolar epithelium.

Amino Acids

Differential expression of gap junction proteins connexin32 and 43 in rat submandibular and sublingual glands.

We examined the expression and localization of the gap junction proteins connexin32 and 43 in rat submandibular and sublingual glands. Western blot analysis with anti-connexin32 and 43 antibodies showed bands of approximately 27 KD and 43 KD, respectively, in both glands. Immunofluorescence microscopy demonstrated the presence of reactive spots for connexin32 between acinar cells in both glands. The frequency of connexin32-positive spots in the submandibular glands was approximately equal to that in the sublingual glands. In contrast, reactive spots for connexin43 were observed at the periphery of the alveolar structures in both glands. The connexin43-positive spots in the sublingual glands were more frequent and larger than those in the submandibular glands. No positive spots for both connexins were detected between duct cells in either gland. Immunoelectron microscopy revealed that connexin32 was localized to the gap junctional membranes between acinar cells. Immunolabeling for connexin43 was located on the gap junctions between thin processes of myoepithelial cells. These results suggest that connexin32 of the gap junction is associated with regulation of the secretory function of acinar cells and that connexin43 is associated with that of contraction of the myoepithelial cells in rat salivary glands.

Animals

Induction therapy with all-trans retinoic acid for acute promyelocytic leukemia: a clinical study of 10 cases, including a fatal [correction of fetal] case with thromboembolism.

Ten patients with acute promyelocytic leukemia (APL) were treated with all-trans retinoic acid (ATRA). Eight of 10 patients achieved complete remission (CR), and among the 8 newly diagnosed cases, 7 achieved CR. Five of 8 CR cases remained in CR after 8 to 30 months. Except for hypotension and a large gastric ulcer resulting from hyperhistaminemia, the adverse effects of ATRA were generally mild. Severe thrombotic tendency occurred in a patient treated with ATRA combined with tranexamic acid. Intensive chemotherapy consisting of daunorubicin (DNR) and other agents was scheduled for the patients who achieved CR with ATRA.

Adult

Empyema following the percutaneous instillation of antifungal agents in patients with aspergillosis.

We report two cases of empyema as a complication of the percutaneous instillation of antifungal drugs for pulmonary and pleural aspergillosis. Case 1 underwent percutaneous administration of amphotericin B and fluconazole for 2 months. Six months later, the patient was found to have an Aspergillus empyema with a bronchopleural fistula. Case 2 with pulmonary and pleural aspergillosis underwent percutaneous administration of amphotericin B for one month. Four months later, the patient underwent pleural drainage due to empyema. Pleural biopsy revealed pleural aspergillosis. In both cases, it was suggested that the preceding Aspergillus infection and percutaneous instillation of antifungals resulted in the development of empyema.

Aged

Restriction fragment length polymorphism analysis in the HLA class III genes of patients with diffuse panbronchiolitis.

Although diffuse panbronchiolitis (DPB) is known to be positively associated with certain major histocompatibility complex (MHC) class I antigens, e.g., HLA-B54 in Japanese patients, it is not clear whether the MHC genes predispose to the disease or are markers for other disease susceptibility gene(s). Because the HLA class III genes such as tumor necrosis factor (TNF) or the fourth component of complement (C4) are localized in the proximity of the HLA-B locus, one or more of these genes might be responsible for susceptibility to DPB. To analyze the role of HLA class III genes in DPB patients, we first evaluated the HLA-B54 association in 32 patients with DPB, and subsequently, studied the restriction fragment length polymorphism (RFLP) of the TNF-alpha and -beta (TNF-alpha/beta) genes as well as the C4A and B (C4A/B) genes in DPB patients and normal individuals. The HLA-B54 antigen was significantly more frequent in DPB patients than in normal individuals (40.3% vs 13.0%, p < 0.001), however, we did not detect a significant association between DPB and gene polymorphisms of either TNF-alpha/beta or C4A/B. Furthermore, there was no evidence of C4A gene deletion in patients with DPB. These results suggest that the HLA-B54 antigen itself might be directly involved in the pathogenesis of DPB.

Bronchiolitis

[A case of acquired immunodeficiency syndrome associated with cryptococcemia and cryptococcal meningitis].

A case of acquired immunodeficiency syndrome (AIDS) developed cryptococcosis which was successfully treated with amphotericin B (AMPH) and fluconazole (FLCZ) is reported. A 52-year-old man was admitted because of pyrexia and oral candidiasis. He had a history of multiple sexual exposures to persons at risk for AIDS in Thailand. On admission, serologic tests for human immunodeficiency virus (HIV)-1 were positive on both EIA and Western blot analysis for anti-HIV-1 antibody. Furthermore, test for cryptococcal antigen and fungal cultures from blood and cerebrospinal fluid revealed that he was suffering from cryptococcemia and cryptococcal meningitis. In spite of identification of Cryptococcus neoformans in his blood and cerebrospinal fluid, the finding of cerebrospinal fluid had a minimal inflammatory response with mild elevation of protein. He was initially treated with intravenous AMPH, 10 to 30 mg a day, for 7 weeks, and then was given oral FLCZ, 400 mg a day, for the suppressive therapy. His fever subsided three weeks after the start of AMPH therapy. He was eventually discharged 9 weeks after the start of therapy without any symptoms, and continued to receive oral FLCZ as an out-patient. Thus, attention should be paid to diagnosis and treatment for cryptococcal meningitis in AIDS patients.

AIDS-Related Opportunistic Infections