Antihypertensive effects of betaxolol, a cardioselective beta-adrenoceptor antagonist, in stroke-prone spontaneously hypertensive rats (SHRSP)

Effects of betaxolol, a cardioselective beta-adrenoceptor antagonist, on blood pressure and hypertensive complications in stroke-prone spontaneously hypertensive rats (SHRSP) were investigated. Betaxolol was provided in a dose of 33 +/- 1.8 mg/kg/day, orally in drinking water, throughout the experimental period. The chronic treatment with betaxolol inhibited the development of hypertension in SHRSP and reduced values of blood urea nitrogen, creatinine, total cholesterol, free cholesterol, triglyceride, phospholipid and HDL-cholesterol in serum. Treatment with betaxolol apparently inhibited the incidence of hypertensive lesions such as cardiac fibrosis, mesenteric vasculitis, proliferative and/or necrotic vasculitis and glomeruli showing collapse or vasculitis in the kidneys. To shorten the time before the onset of hypertension and the subsequent stroke, SHRSP were kept on a SP diet containing 0.39% Na instead of the F-2 diet. When the SHRSP were kept on the SP diet, all of the control SHRSP had cerebral apoplexy and severe hypertensive lesions in the heart and kidney. When betaxolol was chronically administered to SHRSP, cerebral apoplexy and hypertensive lesions in the heart and kidney were inhibited, but the effect on blood pressure was slight. Treatment with betaxolol reduced serum creatinine levels. Our observations show that betaxolol reduces blood pressure and potently inhibits hypertensive complications in SHRSP.     

Improvement in the mechanical properties of artificial blood vessel suitable for the extracranial cerebral artery

Saphenous vein interposition grafts have been commonly used for the reconstruction of occlusive lesions in the extracranial cerebral vessels, such as carotid or vertebral arteries. In contrast, cerebral revascularization using an artificial blood vessel has not been so common. This is due to the fact that conventional artificial blood vessels have been too firm or too rigid for use in the neurosurgery. Another reason is that the long term patency rate of small caliber artificial blood vessels has usually been inferior to that found in autologous vein grafts. The purpose of this study was to develop a soft and compliant artificial blood vessel suitable for cerebrovascular surgery. This new artificial blood vessel is made of polyurethane, porous in structure (porous polyurethane). Thus, multiple small-sized pores exist both in the inner and outer surfaces, and in the wall of the porous polyurethane graft. To test its mechanical properties, we evaluated stress-strain curves and compliance. In comparison to expanded polytetrafluoroethylene graft (Goretex), which has been one of the most commonly used artificial blood vessels in the cardiovascular surgery, the mechanical properties of the porous polyurethane graft more closely resembled those of the common carotid artery in dogs. Thus, porous polyurethane graft was shown to be a soft and compliant new artificial blood vessel. This means not only that it can be maneuvered with technical ease for anastomosis but also that there is a reduction of compliance-mismatch between the host vessel and the artificial vessel. Compliance mismatch has been documented as a major factor in the inducement of intimal hyperplasia, which causes a delayed occlusion.(ABSTRACT TRUNCATED AT 250 WORDS)     

Meningeal large granular lymphocyte lymphoma

A 57-year-old man who presented with leptomeningeal lymphoma was reported. The lymphoma cells in the cere-brospinal fluid were large in size, had atypical nuclei and contained many azurophilic granules in their pale cytoplasm, all of which were consistent with malignant lymphoma of large granular lymphocytes (LGL). Immunohistochemically, tumor cells were positive for cyto-plasmic CD3, UCHL-1, and CD56, markers of natural killer (NK)cells. Epstein-Barr virus encoded small RNA (EBER) was detected in tumor cells by in situ hybridization. No evidence of parenchymal central nervous system or systemic tumor was identified, although at autopsy microscopic lympuoma involvement was found in the pituitary gland and kidney. To our knowledge this is the first autopsy case report of primary meningeal LGL lymphoma.     

Prominent Telangiectasia Associated with Marked Bleeding in CREST Syndrome

A 64-year-old woman with CREST syndrome developed prominent telangiectases mimicking hereditary hemorrhagic telangiectasia (HHT) of Osler-Rendu-Weber. We have been following her since she first came to us with discrete telangiectatic mats and Raynaud's phenomenon 11 years ago. Telangiectatic lesions have been seen on her larynx and esophagus in addition to commonly affected sites. She has experienced spontaneous epistaxis and marked bleeding from the lesions on her lips, oral mucous membrane, and soles. This case illuminates new aspects of telangiectasia in CREST syndrome.     

Withdrawal tolerance and unidirectional non-cross-tolerance in narcotic pellet-implanted mice

Analgesic ED50 values were determined for s.c. morphine, etorphine, heroin and methadone in mice implanted for 3 days with etorphine pellets. Tolerance to morphine (9-fold) was greater than to the other agents (2- to 4-fold). These results agreed with the previously reported unidirectional non-cross-tolerance effect seen after morphine pellet implantation where tolerance to the hydrophilic agent (morphine) was greater than for the more lipophilic agents (etorphine and heroin). As greater tolerance was found to s.c. morphine than for i.c.v. morphine, this manifestation of tolerance was described as a dispositional tolerance. Experimentally, we were able to observe two additional manifestations of tolerance. After pellet removal, the ED50 values for s.c. morphine, heroin and methadone initially increased before returning to control values. Similarly, both morphine and etorphine ED50 values, after i.c.v. administration, initially increased after pellet removal. Because this second manifestation of tolerance occurred during the rapid disappearance of the tolerance-induction drug, it was called withdrawal tolerance. The third manifestation of tolerance, seen after 3 days of pellet implantation, was characterized by the animal's return to a normal nociceptive sensitivity (control tail-flick latency) in the continued presence of the narcotic pellet. Because this adjustment involved an adaptation by the mice to high brain concentrations of narcotic, this third manifestation of tolerance was designated as a physiologic or homeostatic tolerance. The lability of this new homeostatic state (physiologic tolerance) may be associated with an altered sensitivity to naloxone as evidenced by naloxone-induced jumping (precipitated withdrawal).     

Early gastric cancer superimposed on infestation of an Anisakis-like larva: a case report

This report describes a 73-year-old male with early gastric cancer (type IIc) superimposed on infestation of a parasitic larva. Eosinophilic granulomas surrounding a dead worm were seen in the submucosa just beneath the intramucosal tubular adenocarcinomatous lesion measuring 1 X 1cm at the anterior wall in the acid-secreting area. The cancer cells showed lowered and altered mucin production in comparison with the surrounding non-cancerous fundic mucosa. The parasite was identified as an Anisakis-like larva by the presence of typical lateral chords. An immunohistochemical examination revealed that the cancer cells were more strongly positive for IgA and secretory component than the surrounding non-cancerous mucosa, and that IgG, IgA and IgM were detected in plasma cells around the granulomas but IgE and IgD were not. The possibility that the Anisakis-like larva preferentially infested the cancerous mucosa because of the change in mucin, local defect in acid secretion and/or other structural alterations in the area is discussed.     

Fundamental and clinical studies of cefminox in children

Cefminox (CMNX, MT-141), a newly developed injectable cephem antibiotic, was administered intravenously as one shot injection at 3 different dosages of 10, 20 and 40 mg/kg to 9 children; for each dose level 3 children were used. In these children serum and urinary concentrations as well as recovery rates were determined. In addition, in order to determine clinical and bacteriological efficacies of CMNX, it was used in the treatment of 37 cases of various infections consisting of 2 cases of acute tonsillitis, 1 case of acute tonsillitis associated with otitis media, 1 case of acute bronchitis, 1 case of chronic bronchitis, 20 cases of pneumonia, 1 case of pneumonia associated with otitis media, 8 cases of urinary tract infections, 2 cases of purulent lymphadenitis and 1 case of gluteal abscess. The drug was administered intravenously as one shot injection at a mean daily dosage of 76.6 mg/kg, in 4 divided doses in most cases, for a mean period of 6 days. Finally, in 43 cases added of 6 drop out cases which were included in analysis of efficacy side effects and abnormal laboratory findings were examined. The following results were obtained. In 9 cases, which received CMNX at 3 different dosages of 10, 20 and 40 mg/kg for 3 cases each intravenously as one shot injection, mean serum concentrations reached the peaks of 109.4, 218.1 and 357.1 mcg/ml at 5 minutes after injection, respectively, showing dose response relation. The mean half-lives were 1.74, 1.62 and 1.84 hours, respectively. The mean concentrations of CMNX in urine in the same cases as used for determinations of serum concentrations were highest during the 0 approximately 2 hours period, reaching 1,582, 3,304 and 4,618 mcg/ml at the respective doses. The mean recoveries within the first 6 hours were 82.8, 69.8 and 81.3%, the rate for 20 mg/kg group being lower than those obtained for the other groups. This is possibly due to 1 case which showed unusually low recovery rate of 44.4%. When this case is excluded, the recovery rates became similar for all groups. As to clinical results, responses rated as good or higher were obtained for 91.9% of the cases (34 cases/37 cases), with high efficacy rate. No side effects were seen in 43 cases included of drop out cases.(ABSTRACT TRUNCATED AT 400 WORDS)