effect of AT[1] receptor blockade on BAX and BCL-2 expression in bleomycin-induced pulmonary fibrosis

Recent studies have indicated the role of apoptosis and angiotensin in the pathogenesis of bleomycin induced-pulmonary fibrosis. Losartan, an angiotensin type 1 receptor [AT1R] antagonist, has ameliorated apoptosis and fibrosis from bleomycin. In this study, alterations in the expression of apoptosis-regulatory genes [bcl-2 and bax] were investigated in different cells of lung tissue of mice treated with bleomycin in the presence of losartan. Losartan [10 mg/kg, i.p.] was given to mice two days before administration of bleomycin [3 U/kg] and throughout the test period. After two weeks, lung tissues of mice were evaluated for fibrosis by biochemical measurement of collagen deposition and semiquantitative analysis of pathological changes of the lung. The expression of bcl-2 and bax was assessed by immunohistochemical assay using biotin-streptavidin staining method on paraffin-embedded lung tissues. Pre-treatment with losartan significantly [P < 0.05] reduced the increase in lung collagen content and also inhibited the histological changes induced by bleomycin. Immunohistochemical studies showed that losartan significantly [P < 0.05] reduced the bax/bcl-2 expression ratio in the alveolar epithelial cells, lymphocytes, macrophages and interstitial myofibroblasts. Losartan also inhibited the bcl-2 upregulation which was educed by bleomycin in neutrophils. By reduction of bax/bcl-2 ratio as a determinant of susceptibility of a cell to apoptosis, losartan exerted protective effects on the alveolar epithelial cells that may be important in the amelioration of pulmonary fibrosis. These results may help to better understanding of the role of angiotensin II and apoptosis in pulmonary fibrosis

Study on some immunological responses of rainbow trout [onchorhynchus mykiss] to some antigens of streptococcus iniae

Some specific and non-specific immune variables of rainbow trout were assessed following vaccination of fish with formalin killed cells [FKC] and FKC containing extra cellular products [ECP] of S. iniae. Rainbow trout weighing 80-100 g were vaccinated by intraperitoneal [i.p], dip and oral routes using FKC and FKC plus ECP with or without Fround adjuvant [FA] at 16-17 C. Antibody titration, lysozyme activity, serum bacterial killing activity and population of immunocompetent cells were measured on 3, 6, 9, 12, 15 and 18 weeks postvaccination. Data were analyzed by ANOVA. Results showed that the highest antibody titers were produced in i.p vaccinated fish with FKC plus ECP and immunized fish with FKC by dip, respectively. However, administration resulted in the lowest response. Also, the level of antibody production was higher during initial period of post-immunization, while it reduced to lower levels at the end of sampling time. Similar results were obtained when lysozyme activity and bacterial killing capacity of sera samples were estimated. Moreover, while, leukocyte and lymphocyte populations in immunized fish were generally higher than control groups, heterophil and monocyte counts were varied during the sampling periods. Reuslts show that both humeral and cellular immunities of trout are enhanced following immunization of fish with FKC with or without ECP administered as i.p and dip. However, i.p administration of FKC with or without ECP could cause higher response than both dip and oral routes

[Cytolethal distending toxin [CDT] produced by Campylobacter jejuni and Campylobacter coli isolated from chikens by tissue culture method in Isfahan]

Campylobacter jejuni is one of the most common bacterial cause of diarrheal disease in humans throughout the world. Contamination is mainly linked to the consumption of undercooked food products contaminated with Campylobacters. The most characterized toxin proposed is CDT, which has been detected in several Campylobacter species. With regard to the role of broiler chickens in transmission of campylobacter to human and the possible role of CDT in the pathogenesis of Campylobacter, detection of Campylobacter producing CDT is necessary. In this study 368 rectal swabs were collected from chikens. All the specimens were cultured on Skirrows and Blood agar and incubated in microaerophilic conditions at 42°C for 48-72 h. Hella cell was applied to detect CDT in C. jejuni and coil. Campylobacter strains were isolated from 114 [31%] of 368 chicken [101 C. jejuni and 13 C. coli]. Toxin production in C. jejuni and C. coil was 94% and 76.9% respectively. It seems that the majority of C. jejuni and C. coli produce CDT although C. jejuni produces a higher titer

[Clinical, biochemical and microbiological findings of calves diarrhea in a diary herd in Suburbs of Tehran]

Objective: Study of the clinical, biochemical and microbiological factors that cause Neonatal calves diarrhea

Animals: A total of 140 diarrheic neonatal calves [under one month and 35 apparently normal calves]

Procedure: Taking stool sample from rectum of the diarrheic calves, and Blood from jugular vein, using standard methods for detection of bacteria and cryptosporidium measurement and the blood biochemical factors

Statistical analysis: Results were repoted by descriptive scales and software SPSS[version 12] and Chi-Square and t-student

Result: Clinical evaluation revealed that 36/4% of diarrheic samples were sever fluid. 42/9% of diarrheic Samples were yellow in color. 87/9% of calves were thin and vivacious. 65.7% diarrheic calves had poor feeding behaviour and 72.8% of diarrheic calves had second degree dehydration. We separated just E.coli from 28/6% and both E.coli and cryptosporidium from 35% of diarrheic fecal samples. k99 Ecoli Consisted 2/1% of separated E.coli bacteria. Biochemical factors such as Ca,Mg, CI, k and Na also measured by routine methods and compared with control group [35 case] .There wasn't any significant difference in Ca, Mg, Cl, K and Na values between the control group and the group that E.coli was isolated from .But these values differed between the control group and the group which E.coli and cryptospordium were isolated from.Comparison between Ecoli and Ecoli and cryptosporidm groups revealed that there is not any difference between Na and k measures .but Ca, Mg and Cl values were different between these two groups

Clinical implications: The diferences between treatment and control groups could be due to severe diarrhea in which E.coli and cryptosporidium have been isolated