Acute inflammatory response in the stomach of BALB/c mice challenged with coccoidal Helicobacter pylori

An experimental murine model was used to verify the viability and pathogenicity of coccoid Helicobacter pylori. For this purpose, 27 BALB/c mice were inoculated intragastrically with 1 ml broth culture (10(8)organisms/ml) of a coccoid H. pylori clinical isolate. The animals were divided into two groups. Nine were infected on a one-time basis (GA1) and 18 were infected on two consecutive days (GA2). Other 27 mice were inoculated with Brucella broth and divided in the same way; they composed the control group. Mice were killed at 2, 3, 7, 14 and 21 days post inoculation (pi). Fragments of stomach and duodenum were collected, fixed with 12 percent formalin and stained by hematoxilin-eosin and Giemsa for histopathological examination. Until the 14th()day, only reinfected mice had mild-to-moderate inflammatory infiltrate in the stomach. The infiltration was predominantly lymphomonocytic, although plasma cells and eosinophils could be seen. However, at 21st day, severe eosinophilic infiltration was present in the lamina propria and submucosa of gastric corpus. In subgroup GA1, animals presented lymphomonocytic infiltration in the stomach from 14th()day pi. Our results showed that coccoid H. pylori was able to induce an acute inflammatory response in stomach of reinfected mice since the initial periods of infection

Acute inflammatory response in the stomach of BALB/c mice challenged with coccoidal Helicobacter pylori.

An experimental murine model was used to verify the viability and pathogenicity of coccoid Helicobacter pylori. For this purpose, 27 BALB/c mice were inoculated intragastrically with 1 ml broth culture (10(8)organisms/ml) of a coccoid H. pylori clinical isolate. The animals were divided into two groups. Nine were infected on a one-time basis (GA1) and 18 were infected on two consecutive days (GA2). Other 27 mice were inoculated with Brucella broth and divided in the same way; they composed the control group. Mice were killed at 2, 3, 7, 14 and 21 days post inoculation (pi). Fragments of stomach and duodenum were collected, fixed with 12% formalin and stained by hematoxilin-eosin and Giemsa for histopathological examination. Until the 14th()day, only reinfected mice had mild-to-moderate inflammatory infiltrate in the stomach. The infiltration was predominantly lymphomonocytic, although plasma cells and eosinophils could be seen. However, at 21st day, severe eosinophilic infiltration was present in the lamina propria and submucosa of gastric corpus. In subgroup GA1, animals presented lymphomonocytic infiltration in the stomach from 14th()day pi. Our results showed that coccoid H. pylori was able to induce an acute inflammatory response in stomach of reinfected mice since the initial periods of infection.

The prevalence of TT virus infection in renal transplant recipients in Brazil.

BACKGROUND: Recently, TT virus (TTV) was discovered as a potential causative agent for non-A-E hepatitis. Little is known about the prevalence of TTV infection in renal transplant recipients. METHODS: One hundred and seventeen Brazilian renal transplant recipients and 100 normal subjects were examined to determine the prevalence of TTV infection. The TTV DNA in serum and its genotype were examined using polymerase chain reaction and restriction enzyme length polymorphism, respectively. RESULTS: TTV DNA was detected in 63/117 (53.8%) renal transplant recipients in contrast to its detection in 10/100 (10%) normal subjects (P<0.001). There was no statistical difference in the distribution of TTV genotypes between these groups. There was no significant difference in clinical backgrounds between TTV positive and negative patients. CONCLUSIONS: These results indicate a risk for TTV infection in renal transplant recipients in Brazil. They also indicate that TTV itself might not have a strong correlation with the pathogenicity of liver diseases.

New PCR primer pairs specific for Cryptococcus neoformans serotype A or B prepared on the basis of random amplified polymorphic DNA fingerprint pattern analyses.

Thirty-three strains of Cryptococcus neoformans were isolated from clinical specimens, including specimens from AIDS patients in Brazil, and were classified into two serotypes; we detected 31 and 2 strains of serotypes A and B, respectively. Random amplified polymorphic DNA (RAPD) fingerprint pattern analyses of these strains of serotypes A and B showed that the patterns were similar for strains of each serotype when three 10-mer primers were used as the RAPD primers. Comparative studies of the fingerprint patterns of the study isolates with those of the reference strains also showed that the RAPD patterns for strains of each serotype were related and that most of the fingerprint bands existed commonly for all strains of each serotype tested. The common RAPD bands (an approximately 700-bp band for serotype A and an approximately 450-bp band for serotype B) were extracted and the DNA sequences were determined. Using this information, we prepared two and one PCR primer pairs which were expected to be specific for C. neoformans serotypes A and B, respectively. Use of each PCR primer combination thus prepared for serotype A or B was 100% successful in identifying the respective C. neoformans serotypes, including the 33 clinical isolates tested in the present study. Among these combinations, one for serotype A was found to amplify DNA from C. neoformans serotype B as well as serotype A. Serotype B-specific PCR primer pairs amplified DNA from not only serotype B strains but also from serotype C strains. The usefulness of other serotype-specific PCR primers for clinical C. neoformans isolates is discussed.

Prevalence of intestinal parasitic infection in five farms in Holambra, São Paulo, Brazil.

A parasitological survey was carried out on 222 inhabitants of five farms in Holambra, located 30 km north of Campinas, São Paulo, Brazil, on October 1992. Approximately 70% of the inhabitants were found to be infected with at least one species of intestinal parasite. The positive rates of 6 helminths and 7 protozoan species detected are as follows: 5.4% Ascaris lumbricoides; 8.6% Trichuris trichiura; 19.8% Necator americanus; 10.4% Strongyloides stercoralis; 1.4% Enterobius vermicularis; 0.9% Hymenolepis nana; 3.2% Entamoeba histolytica; 2.7% E. hartmanni; 9.9% E. coli; 14.0% Endolimax nana; 2.3% Iodamoeba butschlii; 10.4% Giardia lamblia; 37.8% Blastocystis hominis. The positive rates of helminth infection were generaly higher in the younger-group under 16 years-old than those in the elder group aged 16 or more, whereas the infection rates of protozoan species were higher in the elder group. The infection rate of Strongyloides was found to be 10.4% by a newly developed sensitive method (an agarplate culture methods).

Gelatin particle indirect agglutination test for serodiagnosis of schistosomiasis: comparative study with enzyme-linked immunosorbent assay.

A new serological test, the gelatin particle agglutination test (GPAT), was used for the serodiagnosis of schistosomiasis mansoni. This technique showed the sensitivity (90.6%) and specificity (97.8%) close to those of enzyme-linked immunosorbent assay. The GPAT can be easily and rapidly performed without specialized equipment, by using lyophilized antigen-coated gelatin particles. The test also seems to be useful for mass screening of Schistosoma infection in field conditions.