Mutagenicity,antioxidant potential,and antimutagenic activity against hydrogen peroxide of cashew (Anacardium occidentale) apple juice and cajuina

Fresh and processed cashew (Anacardium occidentale) apple juice (CAJ) are among the most popular drinks in Brazil. Besides their nutritional benefits, these juices have antibacterial and antitumor potential. The chemical constituents of both the fresh juice and the processed juice (cajuina) were analyzed and characterized as complex mixtures containing high concentrations of vitamin C, various carotenoids, phenolic compounds, and metals. In the present study, these beverages exhibited direct and rat liver S9-mediated mutagenicity in the Salmonella/microsome assay with strains TA97a, TA98, and TA100, which detect frameshifts and base pair substitution. No mutagenicity was observed with strain TA102, which detects oxidative and alkylating mutagens and active forms of oxygen. Both CAJ and cajuina showed antioxidant activity as determined by a total radical-trapping potential assay. To test whether this antioxidant potential might result in antimutagenesis, we used a variation of the Salmonella/microsome assay that included pre-, co-, and posttreatment of hydrogen peroxide-exposed Salmonella typhimurium strain TA102 with the juices. CAJ and cajuina protected strain TA102 against mutation by oxidative damage in co- and posttreatments. The antimutagenic effects during cotreatment with hydrogen peroxide may be due to scavenging free radicals and complexing extracellular mutagenic compounds. The protective effects in posttreatment may be due to stimulation of repair and/or reversion of DNA damage. The results indicate that CAJ and cajuina have mutagenic, radical-trapping, antimutagenic, and comutagenic activity and that these properties can be related to the chemical constituents of the juices.     

Plasmid profiles of "Campylobacter upsaliensis" isolated from blood cultures and stools of paediatric patients.

Seventy-three clinical isolates of "Campylobacter upsaliensis" were screened for the presence of plasmids. Plasmid bands were found in 68 (93%) isolates, from which 14 plasmid types were identified. Type 5 was found only in blood-culture isolates, whereas types 7-14 were found only in faecal isolates. Plasmid-free isolates and the other plasmid profiles were present in both faecal and blood isolates. The reproducibility of these profiles was largely dependent on the method of plasmid isolation. The chloroform-phenol lysis method was the most efficient and reliable method of preparing plasmid DNA for plasmid profile analysis. The success of this method may be largely attributable to two factors: (1) the efficacy of cell lysis was independent of either an alkaline agent or of heat; (2) the inactivation of nucleases by the utilisation of chloroform-phenol to lyse the cells. Furthermore, this method of plasmid DNA preparation is ideally suited for use on clinical isolates, especially when rapid plasmid profile analysis may be required.     

Genetic variation and relationships at six VNTR loci in two distinct sample populations in Brazil

BACKGROUND: The Brazilian population has been the focus of intensive genetic study due to admixture characteristics whereas there are few reports on the variability of VNTR loci in Brazil. PRIMARY OBJECTIVE: The aim of this study was to analyse genetic parameters in sample populations from two geographically distant regions: S?o Luis City, in Maranh?o State and Campinas City, in S?o Paulo State. We investigated if distinct colonization influences could produce detectable differences in genetic background. SUBJECT AND METHODS: DNA samples from peripheral drained blood were obtained from unrelated individuals who underwent paternity testing. Allelic variation in six VNTR loci (D2S44, D4S139, D5S110, D8S358, DI0S28 and D17S79) was evaluated. The results were compared to reference databases available for general Latin-derived European and African-American populations as well as for other Brazilian groups. RESULTS: This study reveals that forensic population parameters did not show differences among regions, although we detected admixture values varying between the south-east and north-east of Brazil. CONCLUSIONS: Differences between the two samples are probably due to different admixture proportions of European- and African-derived alleles in each region: both populations are in Hardy Weinberg equilibrium. In addition, the allelic frequency for all loci, in both populations, can be used as database for forensic purposes.     

Creatine supplementation and riluzole treatment provide similar beneficial effects in copper,zinc superoxide dismutase (G93A) transgenic mice

This study investigated the effects of riluzole (Ril), creatine (Cr) and a combination of these treatments on the onset and progression of clinical signs and neuropathology in an animal model of familial amyotrophic lateral sclerosis, the G93A transgenic mouse (n=13-17 per group). The onset of clinical signs was delayed (P<0.05) by about 12 days in all treatment groups compared with control; however, no differences occurred between treatments. All animals were killed at 199 days of age. At the end of the experimental period the severity of clinical signs was less (P<0.05) with all treatments compared with control. Again no differences between treatments were observed. The treatments had no effect on the number of neurons in ventral horns of the lumbar region of the spinal cord. Transgenic mice ingesting Cr displayed elevated (P<0.05) total Cr levels in cerebral hemispheres (5%) and spinal cord (8%), but not skeletal muscles. These data demonstrate that treatment with Ril and Cr were both effective in delaying disease onset and clinical disability. To the age of killing, no additional benefit was conferred by co-administration of Ril and Cr.     

Complex CGH alterations on chromosome arm 8p at candidate tumor suppressor gene loci in breast cancer cell lines

Loss of genetic material from chromosome arm 8p occurs frequently in human breast carcinomas, consistent with this region of the genome harboring one or more tumor suppressor genes (TSGs). We used the complementary techniques of microsatellite-based LOH, high-density FISH, and conventional CGH on 6 breast cancer cell lines (MCF7, SKBR3, T47D, MDA MB453, BT549, and BT474) to investigate the molecular cytogenetic changes occurring on chromosome 8 during tumorigenesis, with particular emphasis on 6 potential TSGs on 8p. We identified multiple alterations of chromosome 8, including partial or complete deletion of 8p or 8q, duplication of 8q, and isochromosome 8q. The detailed FISH analysis showed several complex rearrangements of 8p with differing breakpoints of varying proximity to the genes of interest. High rates of LOH were observed at markers adjacent to or within PCM1, DUSP4/MKP2, NKX3A, and DLC1, supporting their status as candidate TSGs. Due to the complex ploidy status of these cell lines, relative loss of 8p material detected by CGH did not always correlate with microsatellite-based LOH results. These results extend our understanding of the mechanisms accompanying the dysregulation of candidate tumor suppressor loci on chromosome arm 8p, and identify appropriate cellular systems for further investigation of their biological properties.     

Sertoli-Leydig cell tumor of the ovary with alpha-fetoprotein production

A case of poorly differentiated Sertoli-Leydig cell tumor with elevated serum alpha-fetoprotein (AFP) levels occurred in a 17-year-old girl. No germ cell component and no heterologous elements were identified, but a retiform pattern was present. Immunohistochemical studies demonstrated immunoreactivity for AFP and testosterone in Leydig's cells only. Secretion of AFP by Sertoli-Leydig cell tumors has rarely been mentioned previously, and its mechanism is difficult to explain. Non-germ cell tumors must be considered in the differential diagnosis of ovarian tumors with elevated serum AFP levels.     

Extended-spectrum beta-lactamases in clinical isolates of enterobacteria in Mexico

Resistance to extended-spectrum cephalosporins within members of the family Enterobacteriaceae occurs virtually world-wide. Nevertheless, nothing was known about this problem among isolates from Mexico. To address this issue, we studied oximino-cephalosporin resistant isolates of Klebsiella pneumoniae (13), Escherichia coli (7), and Enterobacter cloacae (23) recovered from patients in Mexico City hospitals during 1990 to 1992. In the presence of clavulanic acid, these strains increased susceptibility to cefotaxime and ceftazidime (MIC90 64 and >256 microg/ml, respectively). The ability of these isolates to transfer resistance to both antibiotics by conjugation was most successfully demonstrated by K. pneumoniae. In all the clinical isolates tested, the largest plasmid coded for the extended-spectrum beta-lactamases (ESBL). Characteristics of pI, by isoelectric focusing (IEF)/bioassay and DNA hybridization with specific probes of TEM and SHV, indicated that in most of the clinical isolates and all transconjugates, the most frequent beta-lactamase coded were SHV-derived (20 strains as 41% of isolates) and a plasmid-encoded beta-lactamase (12 strains as 25% of isolates) (with a pI of >8.2), which is not related to TEM/SHV. Apparently, isolates from Mexico show characteristics similar to isolates from other geographic areas. The type of beta-lactamases coded in these resistant isolates is documented for the first time in Mexico.     

Comparison of real-time PCR protocols for differential laboratory diagnosis of amebiasis

Specific identification of Entamoeba spp. in clinical specimens is an important confirmatory diagnostic step in the management of patients who may be infected with Entamoeba histolytica, the species that causes clinical amebiasis. Distinct real-time PCR protocols have recently been published for identification of E. histolytica and differentiation from the morphologically identical nonpathogenic Entamoeba dispar. In this study, we compared three E. histolytica real-time PCR techniques published by December 2004. The limits of detection and efficiency of each real-time PCR assay were determined using DNA extracted from stool samples spiked with serially diluted cultured E. histolytica trophozoites. The ability of each assay to correctly distinguish E. histolytica from E. dispar was evaluated with DNA extracted from patients' stools and liver aspirates submitted for confirmatory diagnosis. Real-time PCR allowed quantitative analysis of the spiked stool samples, but major differences in detection limits and assay performance were observed among the evaluated tests. These results illustrate the usefulness of comparative evaluations of diagnostic assays.     

Serotypes of carriage and invasive isolates of Streptococcus pneumoniae in Brazilian children in the era of pneumococcal vaccines

Nasopharyngeal carriage of Streptococcus pneumoniae is a key factor in the development of invasive disease and the spread of resistant strains within the community. A single nasopharyngeal swab was obtained from 648 unvaccinated children aged <5 years, either healthy or with acute respiratory tract infection or meningitis, during the winters of 2000 and 2001. The overall pneumococcal carriage rate was 35.8% (95% CI 32.1-39.6). The pneumococcal serotypes found most frequently in the nasopharynx were 14, 6B, 6A, 19F, 10A, 23F and 18C, which included five of the seven serotypes in the currently licensed seven-valent conjugate vaccine (PCV7); serotypes 4 and 9V were less common. Serotypes 1 and 5 were isolated rarely from the nasopharynx. A comparison of 222 nasopharyngeal isolates with 125 invasive isolates, matched for age and time to the carrier isolates, showed a similar prevalence of penicillin non-susceptible pneumococci (PNSp) (19.8% and 19.2%, respectively). PNSp serotypes were similar (6B, 14, 19F, 19 A, 23B and 23F) for carriage and invasive disease isolates. The coverage of PCV7 for carriage isolates (52.2%) and invasive isolates (62.4%) did not differ significantly (p 0.06); similarly, there was no significant difference in PCV7 coverage for carriage isolates (34.5%) and invasive isolates (28.2%) of PNSp. These data suggest that PCV7 has the potential to reduce pneumococcal carriage and the number of carriers of PNSp belonging to vaccine serotypes.