Removal of micro-organisms by filtration through unwoven cloth coated with a pyridinium-type polymer.

Unwoven cloth coated with 32 mg/g of a copolymer of N-benzyl-4-vinyl-pyridinium chloride and styrene was found to be effective in removing micro-organisms from water. In experiments demonstrating removal of Escherichia coli by filtration through ten sheets of the unwoven cloth, the rate of removal was 99.99% at a filtration rate of 2.6 cm/h, and remained at 99% even at a high filtration rate of 300 cm/h and a low influent concentration of the bacterial cells such as 10(3) cells/ml. The rate of removal tended to increase with a decrease in the influent bacterial concentration. Seven other bacteria and two yeasts were effectively removed by filtration through the unwoven cloth. Filtration through the unwoven cloth was also effective in removing spores of fungi from water but was not very effective in removing bacteriophage T4 from aqueous solution.     

Major histocompatibility complex class II antigens on renal cell cancer--immunohistochemical study and effect on their expression by interferon

Products of major histocompatibility complex (MHC) play important roles in immune reaction. Class II MHC antigens serve as restriction elements for cells presenting antigens to CD4-positive helper T cells and also as histocompatibility antigens responsible for graft rejection. Furthermore, it was reported that expression of class II antigens on tumor cells increases immunogenicity in the murine system. In an attempt to investigate the relationship between renal cell cancer (RCC) and host's immune responses, we examined the expression of class II MHC antigens on RCC tissues of 30 cases and tumor cell lines. Immunohistochemical study showed that class II antigens were detected on 29 out of 30 RCC tissues to various degrees with an order of positivity DR greater than DP greater than DQ but not normal renal tubular cells. Significant correlation was found between the expression of DQ or DP and the degree of lymphocyte infiltration. Three lines of RCC were examined by flowcytometric analysis, and were found to lack class II antigens. In KRC/Y and ACHN, however, HLA-DR-positive cells and in KRC/Y a smaller number of HLA-DP-positive cells were found when these cells were treated with interferon-gamma but not interferon-alpha. The result suggests that the expression of class II antigens on RCC might be modified by interferon-gamma which is produced by tumor infiltrating lymphocytes or administrated for cancer treatment. Their expression is considered to affect host's immune response to RCC.     

Pharmacokinetics of amikacin in children and neonates

To evaluate pharmacokinetics of amikacin (AMK), one of the aminoglycoside antibiotics, children with ages from 2 days to 11 years were treated with various doses by various administration routes, and both plasma and urinary levels of AMK were determined. The following is a summary of the results obtained: 1. Of 6 children, three were treated with 2.0 mg/kg of AMK by a 30-minute intravenous drip infusion, and the other 3 with 4.0 mg/kg by a 60-minute. Peaks of average plasma levels were observed at the ends of the infusions in both cases, and their levels were 9.23 and 13.67 micrograms/ml, respectively, showing a dose-dependency. Both half-lives and areas under plasma concentration-time curves (AUCs) were similar to those of adults. However, the volume of distribution (Vd) showed a lower value than that of adults. Peaks of average urine levels were 149.3 micrograms/ml with 2.0 mg/kg in 0-2 hours after the start of the infusion and 223.3 micrograms/ml with 4.0 mg/kg in 2-4 hours. Average urinary recovery rates within 6 hours after the start of the infusion were 95.4% with 2.0 mg/kg and 85.7% with 4.0 mg/kg. These recoveries were equal to or higher than that of adults. 2. When 3.0, 4.0 and 6.0 mg/kg of AMK were administered to 3 groups of mature or premature babies by intramuscular injection, average peak levels of AMK in plasma were 6.26, 8.61 and 12.60 micrograms/ml, respectively, at 30 minutes after the injection, showing dose-dependency. In these groups, the younger the day age after birth was, the longer the half-life became. The AUCs were larger as the half-life became longer. The Vd was larger than that in the intravenous drip infusion group, but, any particular was not observed. Average peak levels of AMK in urine were 78.83 micrograms/ml at 4-6 hours with a dose level of 3.0 mg/kg, 99.17 micrograms/ml at 2-4 hours with 4.0 mg/kg and 139.20 micrograms/ml at 0-2 hours with 6.0 mg/kg. Average urinary recovery rates within 6 hours were 36.57% with 3.0 mg/kg, 34.67% with 4.0 mg/kg and 43.77% with 6.0 mg/kg. These recovery rates were markedly lower than those observed in adults and children. One of the causes of this low recovery is that mature and premature babies have immature renal functions. 3. When 3.0 mg/kg of AMK was administered to three premature babies by a 30-minute intravenous drip infusion, the average peak plasma levels was 7.61 micrograms/ml at the end of the drip infusion.(ABSTRACT TRUNCATED AT 400 WORDS)     

Ultrastructure of lentigo maligna in the oral cavity

A rare case of lentigo maligna in the oral cavity was investigated by light and electron microscopy. Cutaneous lentigo malignas often develop to malignant melanomas. However, the electron microscopic examination revealed that even though there were a large number of melanosomes, most of them were late stage and had membrane structure, and positive staining with HMB-45 was not recognized. From our findings, it is difficult to conclude that oral lentigo malignas develop malignant melanomas, and thus further studies are needed.     

Expression of intercellular adhesion molecule-1 on transitional cell cancer. Possible significance in immunity against tumor cells.

Immunohistochemical examination demonstrated expression of intercellular adhesion molecule-1 (ICAM-1) on 17 of 44 transitional cell cancers (TCCs) but not on normal transitional cells. ICAM-1 was frequently expressed in higher stage tumors, especially in those with abundant immune cells scattered within tumor. Analysis of infiltrating immune cells showed that they were composed mainly of T lymphocytes and a smaller number of macrophages bearing the lymphocyte function-associated antigen-1 (LFA-1). Expression of ICAM-1 on transitional cell cancer cell lines was augmented by in vitro treatment with interferon-gamma, tumor necrosis factor-alpha, and interleukin-1 beta. Furthermore, Northern blot analysis revealed higher quantities of a 3.3-kb RNA in T24 cells exposed to interferon-gamma or tumor necrosis factor-alpha. These results suggest that the expression of ICAM-1 on transitional cell cancers might be modified by cytokines produced by infiltrating immune cells, which might facilitate immune responses against cancer cells.     

Disease associations and altered immune function in CD45 138G variant carriers

The CD45 antigen is a haemopoietic cell specific tyrosine phosphatase essential for antigen receptor mediated signalling in lymphocytes. Expression of different patterns of alternatively spliced CD45 isoforms is associated with distinct functions. We recently identified a polymorphism in exon 6 (A138G) of the gene encoding CD45 (PTPRC) that results in altered CD45 splicing. The 138G allele is present at a high frequency among Japanese (23.7%), with 5.1% individuals homozygous for the G allele. In this study we show that the A138G polymorphism is the cause of altered CD45 isoform expression, promoting splicing towards low molecular weight CD45 isoforms. We further report that the frequency of A138G heterozygotes is significantly reduced in number in cohorts of patients with autoimmune Graves' disease or hepatitis B infection, whereas G138G homozygotes are absent from a cohort of Hashimoto's thyroiditis patients. We also show that 138G individuals exhibit altered cytokine production in vitro and an increased proportion of memory T cells. These data suggest that the 138G variant allele strongly influences these diseases by modulation of immune mechanisms and may have achieved its high frequency as a result of a natural selection probably related to pathogen resistance.     

Case of minocycline-induced pneumonitis with bilateral pleural effusion]

A 51-year-old man was admitted to our hospital with fever, dry cough and dyspnea. He had taken minocycline for 11 days because of urinary tract infection. Chest X-ray on admission showed diffuse reticular shadows in bilateral lung fields with bilateral pleural effusion. Cessation of minocycline led to spontaneous improvement of symptoms and radiographic findings. The lymphocyte stimulation test for minocycline with peripheral blood and pleural effusion were negative. After provocation test with minocycline, he developed fever and dry cough and bilateral ground glass opacity appeared on his chest X-ray. He was diagnosed as minocycline-induced pneumonitis and recovered rapidly following corticosteroid therapy.