Search PubMed⌕ Search

Biomedical subjects

S Arai

Publications and source records attributed to S Arai.

568 records · Page 32Linked to original sources

Immunohistochemical characterization of calf pneumonia produced by the combined endobronchial administration of bovine herpesvirus 1 and Pasteurella haemolytica.

Ten calves ("group 4") were inoculated endobronchially with Pasteurella haemolytica 4 days after inoculation with bovine herpesvirus 1 (BHV-1). Four calves (group 3) were similarly inoculated with P. haemolytica alone, and three (group 2) with BHV-1 alone. All group 4 animals showed severe respiratory signs and had bilateral lobar pneumonia; one died 6 days after inoculation with P. haemolytica. Two types of pneumonic lesion were observed. One was characterized by interlobular and interstitial lymphatic thrombosis, fibrinous pleuritis and coagulative necrosis, and the other by necrotizing bronchiolitis with intranuclear inclusion bodies. The former type of lesion was associated with the presence of P. haemolytica antigen and the latter with the presence of BHV-1 antigen. The weight of infection of BHV-1 and P. haemolytica in bronchoalveolar (BAL) fluid was clearly reflected in the immunohistochemical demonstration of the corresponding antigens in BAL fluid cells. Group 4 calves differed from the calves of groups 1-3 in showing 10-1530 times more endotoxin in BAL fluid. These findings suggested that BHV-1 infection partly destroyed the clearance mechanisms of the respiratory tract epithelium and exacerbated the subsequent P. haemolytica infection.

Animals↗

The effectiveness of rectal administration of insulin suppository on normal and diabetic subjects.

The effectiveness of insulin administration by rectal suppository was examined in normal and non-insulin-dependent nonobese diabetic subjects. A 100-U insulin suppository (mean 1.8 U/kg) given to the diabetic subjects caused four times as great a fall in plasma glucose compared with the normal subjects given the same dose (mean 1.6 U/kg). The insulin response after suppository administration demonstrated a significantly positive correlation (r = 0.83, P less than 0.01) with the plasma glucose level before administration. Diabetic subjects given a 100-U insulin suppository (mean 1.7 U/kg) 15 min after meals three times daily showed a significant (P less than 0.05) improvement in postprandial hyperglycemia accompanied by a restoration of the normal circadian profile of plasma IRI and a reduction of urinary glucose from 26 +/- 5.9 to 2.0 +/- 1.0 g/day. No untoward reactions were observed. These data strongly imply a unique characteristic of the insulin suppository in spite of low bioavailability.

Adult↗

Transient encephalopathy following a single exposure of high-dose methotrexate in a child with acute lymphoblastic leukemia.

An episode of transient encephalopathy after the first course of intravenous high-dose methotrexate (HD-MTX; 1000 mg/m2) was observed in a 4-year-old girl with acute lymphoblastic leukemia. The neurological abnormalities took place 5 days after HD-MTX therapy. She experienced complex partial seizure and left hemiparesis, which resolved spontaneously in 5 days. Cranial computed tomographic scan and magnetic resonance imaging showed multiple low-density lesions in bilateral hemispheres. It is well appreciated that neurotoxicity from MTX follows prolonged exposures, often accompanying or following radiation therapy. To our knowledge, however, there have been no reports that such neurological complications developed following a single exposure of HD-MTX in patients with ALL. Follow-up electroencephalograms showed that she had periodic lateralized epileptiform discharges (PLEDS), suggesting functional deafferentation of cortical neurons following HD-MTX. Moreover, the serum and CSF MTX levels following a second low-dose course and her clinical course suggested that she had presumably central nervous system leukemia at the time of HD-MTX therapy, which might have been related to neurological complications. The pathogenesis of MTX-induced neurotoxicity is discussed.

Antineoplastic Combined Chemotherapy Protocols↗

Apoptosis of human leukemia cells induced by Artepillin C, an active ingredient of Brazilian propolis.

Artepillin C (3,5-diprenyl-4-hydroxycinnamic acid) is an active ingredient of Brazilian propolis that possesses anti-tumor activity. When Artepillin C was applied to human leukemia cell lines of different phenotypes, namely, lymphocytic leukemia (7 cell lines of T-cell, 5 cell lines of B-cell), myeloid and monocytic leukemia and non-lymphoid non-myeloid leukemia cell lines in vitro, Artepillin C exhibited potent cytocidal effects and induced marked levels of apoptosis in all the cell lines. The most potent effects were observed in the T-cell lines. Apoptotic bodies and DNA fragmentation were induced in the cell lines after exposure to Artepillin C. DNA synthesis in the leukemia cells was clearly inhibited and disintegration of the cells was confirmed microscopically. Apoptosis of the leukemia cells may be partially associated with enhanced Fas antigen expression and loss of mitochondrial membrane potential. In contrast, although Artepillin C inhibited the growth of pokeweed mitogen (PWM)-stimulated normal blood lymphocytes, it was not cytocidal to normal unstimulated lymphocytes. These results suggested that Artepillin C, an active ingredient of Brazilian propolis, has anti-leukemic effects with limited inhibitory effects on normal lymphocytes.

Antineoplastic Agents↗

The impact of FK506 on graft coronary disease of rat cardiac allograft--a comparison with cyclosporine.

We studied the impact of FK506, a potent immunosuppressant, on graft coronary disease and graft-infiltrating lymphocyte subset after rat heart transplantation. Fisher rat heart grafts transplanted into Lewis rat recipients were divided into three groups: control (n = 7), rats treated with FK506 at a dose of 0.32 mg/kg/day intramuscularly (n = 7), and rats treated with cyclosporine at a dose of 10 mg/kg/day intramuscularly (n = 7). Grafts were removed on day 71 in the treated groups and on rejection in the control group. We blindly scored graft rejection and graft coronary disease on a scale of 0 to 4. Graft-infiltrating lymphocytes were investigated by flow-cytometric analysis with the following monoclonal antibodies: W3/25, anti-helper T lymphocyte; OX8, antisuppressor and cytotoxic T lymphocyte; and OX39, antiinterleukin-2 receptor. No difference of graft rejection was found between the two treated groups (FK506 1.66 +/- 0.49 versus cyclosporine 1.45 +/- 0.37), but the FK506 group showed severe graft coronary disease (FK506 2.14 +/- 0.82 versus cyclosporine 0.78 +/- 0.17; p less than 0.01) in this model. In flow-cytometric analysis, we found an increased proportion of OX8-positive lymphocytes (FK506 25.7 +/- 6.4 versus cyclosporine 4.9 +/- 2.4, p less than 0.01). These results suggest that suppression of cytotoxic T lymphocytes may be involved in graft coronary disease.

Animals↗

Mycoplasma interaction with lymphocytes and phagocytes: role of hydrogen peroxide released from M. pneumoniae.

Interferon (IFN) production by human peripheral lymphocytes stimulated with M. pneumoniae was investigated. The hydrogen peroxide released from M. pneumoniae was responsible for the induction of IFN from lymphocytes, since horseradish peroxidase inhibited the IFN production and abrogated the activity of IFN production in the supernatant of M. pneumoniae. The antiserum neutralizing IFN alpha and IFN beta failed to neutralize partially interferon produced by lymphocytes. Treatment either with pH 2.0 or antiserum neutralizing human IFN gamma resulted in a partial reduction of interferon. These results indicate that interferon produced by human lymphocytes stimulated with M. pneumoniae includes both types of IFN gamma and IFN beta.

Adult↗