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R Kawana

Publications and source records attributed to R Kawana.

At least 37 records · Page 2Linked to original sources

[In vitro synergy between cefotaxime and its main metabolite, desacetylcefotaxime].

In vitro synergistic interaction between cefotaxime (CTX) and its main metabolite, desacetyl-cefotaxime (DCTX), against 7 species of clinical isolates (23-27 strains per species) was examined. Complete or partial synergy was noted with a 1:1 combination of CTX and DCTX against 22-78% of the Bacteroides fragilis, Staphylococcus aureus, Citrobacter freundii, Pseudomonas cepacia and Enterobacter cloacae isolates examined. Antagonistic effects of the drugs appeared against 11% of Proteus vulgaris and 4% of Serratia marcescens. When combined at various ratios by the checkerboard method and tested against B. fragilis, CTX and DCTX were found to act synergistically, and no antagonism occurred. The combined use of CTX and DCTX exhibited strong bactericidal activity against B. fragilis and inhibited bacterial regrowth. An experiment with concentrations of CTX and DCTX simulating human serum levels after intravenous administration also showed that the coexistence of DCTX augmented bactericidal activity of CTX against B. fragilis and brought inhibitory effects on bacterial regrowth. It is presumed from the present results that clinically applied CTX would have more potent effects than expected from in vitro sensitivity test data.

Bacteria↗

An epidemic of acute hemorrhagic conjunctivitis in the city of Sao Paulo.

This is a clinical and laboratory report on 98 patients with acute viral conjunctivitis who were referred to the Eye Clinic of the Escola Paulista de Medicina of Sao Paulo, Brazil, from February 1983 to February 1984. It was planned with the objective of confirming the importance of adenovirus and enterovirus 70 as etiological agents of viral conjunctivitis. The occurrence of an outbreak of acute hemorrhagic conjunctivitis during the summer of 1984 permitted a better study of enterovirus 70. In addition, we could demonstrate that sporadic cases, from March to July 1983, were caused by the same virus. This fact confirmed the idea that the spread of the disease was not related to the recent arrival of the virus in the community, but to weather conditions of heat and high humidity.

Adenovirus Infections, Human↗

Molecular epidemiology of adenoviral conjunctivitis in Sapporo, Japan, and Manila, the Philippines.

DNA restriction endonuclease analysis was carried out on 48 adenovirus isolates from the conjunctival swabs of patients with acute conjunctivitis. Samples were obtained in Sapporo, Japan, and Manila, the Philippines, from October 1983 to October 1984. We identified new genomic variants among the isolates of Ad3 in Sapporo, and Ad4 and Ad11 in Manila, and these were designated as Ad3f, Ad4b, Ad11a and Ad11b, respectively. Ad7 isolates in Manila were identical to Ad7b reported by Wadell et al. In Sapporo, no Ad7 was isolated during the period of this study. One isolate in Sapporo, which was neutralized by both Ad34 and Ad35 antisera, showed identical restriction patterns to Ad35 prototype strain (Holden) with SmaI, BamHI and HpaI. However, with HindIII, the pattern was identical to that of Ad34 prototype strain (Compton). This isolate was tentatively designated as Ad34/35. Ad8 isolates in Sapporo were identical to Ad8B detected there from 1977 to 1981, while Ad8 isolates in Manila were prototype (Trim) strains. In both cities Ad19 isolates were all identical to Ad19a and Ad37 isolates were all prototype (GW). Genomic variants of Ad isolates in both cities are as follows: (Table: see text).

Adenoviridae Infections↗

Viral conjunctivitis with special reference to adenovirus type 37 and enterovirus 70 infection.

The clinical and etiological findings in 727 patients with viral conjunctivitis treated from January 1982 through December 1984 at Aoki Eye Clinic in Sapporo, Japan, were presented. The age of the patients ranged from 11 days to 88 years, and the monthly incidences of the disease from 18 to 131 cases, with a clustering in the summer season. The etiological diagnosis was established in 399 (54.9%) of the 727 patients: adenovirus (Ad) 3 in 45 cases; Ad4 in 98 cases; Ad8 in 57 cases; Ad19 in 23 cases; Ad37 in 51 cases; untyped Ad in 33 cases; enterovirus (EV) 70 in 60 cases; herpes simplex virus type I in 24 cases and varicella-zoster virus in 4 cases. The clinical pictures of adenovirus 37 conjunctivitis were generally similar to those of adenovirus 8 conjunctivitis, and subconjunctival hemorrhage was more frequently seen in cases of EV70 conjunctivitis. EV70 cases showed nosocomial infection. In addition to Ad8, Ad37 seems to play an important role as a causative agent of epidemic keratoconjunctivitis in Japan.

Adenoviridae Infections↗

Cardiovascular diseases due to viruses.

In acute myocardiopathy and pericardiopathy, Coxsackie virus B infections are increasingly recognized as a cause of primary myocardial disease and may cause chronic cardiovascular disease. With other viruses, such as cytomegaloviruses and rubella virus, transplacental infection during pregnancy may occur, and this can cause the congenital rubella syndrome, which involves heart abnormalities. Other viruses are now under study. Myocarditis was observed in a newborn infant infected with Coxsackie virus B3, which was isolated by tissue culture methods. Experimental infection of Coxsackie virus A and B was studied in suckling mice and the histopathologic changes in heart muscle were observed. Laboratory findings of viral infection are very useful for clinical diagnosis, however care needs to be taken with respect to the obtaining of specimens, diagnostic procedures, and the assessment of results.

Animals↗

Myocardial lesions by Coxsackie virus B3 and cytomegalovirus infection in infants.

Immunofluorescent and electron-microscopic studies were performed to determine the distribution of viral antigens and particles and to clarify the relationship to myocardial lesions in two autopsy cases with generalized infection of Coxsackie virus B3 (CVB3) or cytomegalovirus (CMV). Case 1 was a full-term newborn female infant, without any congenital anomalies, who died of cardiac failure 10 days after birth. CVB3 was isolated from the blood before death. Necrosis of the muscle fibers was observed, frequently accompanying calcification. Numerous histiocytes and a few lymphocytes and neutrophils had infiltrated in and around the necrotic areas. Immunofluorescent study (IF) revealed CVB3 antigen in the muscle fibers and vascular endothelial cells. Case 2 was a female infant, born at 28 weeks of gestation, who died of fatal arrhythmia 50 days after birth. The infant had hemocephalus and a history of idiopathic respiratory distress and underwent an operation for patent ductus arteriosus. Cytomegalic cells were frequently found in the vascular endothelial cells in the myocardium and occasionally in muscle fibers. IF showed the presence of CMV antigen in both endothelial cells and muscle fibers. CVB3 and CMV antigens were detected predominantly in vascular endothelial cells rather than in the muscle fibers. Blood flow disturbance due to endothelial damage is a cause of the myocardial lesion in addition to the direct invasion of the muscle fibers by the virus.

Antigens, Viral↗

An immunofluorescent study of generalized Coxsackie virus B3 infection in a newborn infant.

An autopsy case of a 10-day-old newborn with generalized infection of Coxsackie virus B3 (CBV3) was reported. CBV3 was isolated from the blood before death. The patient died of cardiac failure. An immunofluorescent study was carried out on autopsy specimens fixed in formalin and embedded in paraffin. CBV3 antigen was detected in the heart, brain, kidney, lungs, spleen, thymus, and pancreas. In the pancreas CBV3 antigen was predominantly seen in the islet cells. No CBV3 antigen was found in the liver and adrenal glands. Electron microscopic examination revealed virion-like particles, 20 nm in diameter, in the endothelial cells of the myocardium.

Antigens, Viral↗