Phenotypic and genetic features of enteropathogenic Escherichia coli isolates from diarrheal children in the Ribeirão Preto metropolitan area,São Paulo State,Brazil

This study was designed to characterize a collection of 60 enteropathogenic Escherichia coli (EPEC) isolates from diarrheic feces of patients in the Ribeirão Preto metropolitan area regarding different phenotypic and molecular features. We examined antibiotic resistance profiles, occurrence of virulence factors‐encoding genes, intimin subtypes and the correlation of serotypes among typical (tEPEC) and atypical (aEPEC) EPEC isolates. The results demonstrated that atypical EPEC was more heterogeneous than typical EPEC concerning the characteristics investigated and 45.2% do not belong to classical EPEC serogroups. Intimin subtype β was the most frequent among the EPEC isolates (46.7%), being detected in both tEPEC and aEPEC. The majority of aEPEC isolates presented localized adherence‐like (LAL) pattern to HEp‐2 cells, although aEPEC isolates displaying diffuse adherence (DA) or non‐adherent were also detected. High prevalence of antimicrobial resistance was found for ampicillin, cephalothin, sulfonamide and tetracycline. In general, tEPEC isolates were more resistant to the antimicrobials tested than aEPEC isolates.     

Heterogeneity of anticardiolipin antibody

The antibody to cardiolipin(ACA) was tested in patients with systemic rheumatic disease. The frequency of IgG ACA was 46/100(46.0%) in systemic lupus erythematosus(SLE). In other rheumatic disease, this was less than 20%. Significant correlation between the presence of IgG ACA and thrombosis and/or thrombocytopenia was found in patients with SLE. Eight sera containing high titered IgG ACA from lupus patients were selected for further inhibition study. Inhibitors were consisted of cardiolipin(CL), phosphatidyl(p-)serine, p-inositol, p-glycerol, p-ethanolamine, p-choline, ds-DNA, ss-DNA, fresh platelets(PLT)and fresh red blood cells(RBC). All sera were markedly inhibited by negatively charged phospholipids. In 4 sera(group B), there was moderate inhibition by ss-DNA, ds-DNA, PLT and RBC. In another 4 sera(group A), mild but significant inhibition was obtained by PLT alone. The number of platelet in group A was less than that in group B. There were some differences in inhibitory activity, suggesting heterogeneity of antibody to CL. It may be possible to speculate that heterogeneity of IgG ACA cause various combination of clinical features such as thrombocytopenia and thrombosis.     

Spontaneous age-associated amyloidosis in senescence-accelerated mouse (SAM)

Morphological studies on spontaneous systemic amyloidosis were conducted on 222 senescence-accelerated mice (SAM) (P) and on 150 mice in the senescence-resistant series (R).Among the pathologic findings, amyloidosis showed the highest incidence in both SAM (79.7%) and R (32.7%) Although an extensive deposition of amyloid was evident in some aged mice in the R series, a more severe amyloidosis occurred with a higher incidence in the P series. There was a statistical significance between the incidence of amyloidosis and age, in both the P and R series. There were no differences in organ distribution and mode of amyloid deposition between the P and R series or between the sexes. In about 60% of the amyloid-positive cases in the 28 killed SAM and 7 mice in the R series, there were no signs of inflammation or neoplasm.The morphological features in SAM more closely resembled those seen in cases of murine spontaneous senile amyloidosis than the features seen in cases of experimentally induced amyloidosis. This model is expected to be a valuable tool with which to assess the relationship between amyloid deposition and the aging process or senescence, perhaps even cases of human senile amyloidosis.     

Biochemical, genetic, and epidemiologic characterization of Haemophilus influenzae biogroup aegyptius (Haemophilus aegyptius) strains associated with Brazilian purpuric fever.

Brazilian purpuric fever (BPF) is a recently recognized fulminant pediatric disease characterized by fever, with rapid progression to purpura, hypotensive shock, and death. BPF is usually preceded by purulent conjunctivitis that has resolved before the onset of fever. Both the conjunctivitis and BPF are caused by Haemophilus influenzae biogroup aegyptius (formerly called H. aegyptius). Isolates from 15 BPF cases, mainly from blood or hemorrhagic cerebrospinal fluid, case-associated isolates from 42 persons in towns where BPF cases occurred, and control strains from 32 persons in towns without BPF cases were characterized biochemically, genetically, and epidemiologically. Results indicated that a single clone was responsible for all BPF cases identified in six Brazilian towns from 1984 through 1986. All of 15 (100%) case strains were the same clone as was 1 of 32 (3%) control strains (P = less than 10(-8). Isolates of the clone were preferentially intrarelated by DNA hybridization (99% relatedness, hydroxyapatite method at 60 and 75 degrees C) and were separable from other H. influenzae biogroup aegyptius strains (approximately 90% relatedness at 60 degrees C and 82% relatedness at 75 degrees C). All isolates of the BPF clone and no other strains contained a 24-megadalton plasmid of restriction endonuclease type 3031, were of a single multilocus enzyme mobility type, were of a single sodium dodecyl sulfate-polyacrylamide gel electrophoresis type, and were in one of two ribosomal DNA restriction patterns. All BPF clone isolates reacted with monoclonal antibodies produced from a case strain; only 3 of 62 (5%) other strains reacted with this monoclonal antibody. Ninety percent of BPF clone strains and 27% of other strains were relatively resistant to sulfamethoxazole-trimethoprim.     

Women with endometriosis have increased levels of placental growth factor in the peritoneal fluid compared with women with cystadenomas

BACKGROUND: To assess the release of placental growth factor (PlGF) into peritoneal fluid in women with and without endometriosis, we measured its concentration with reference to disease stage, the presence of red endometriotic lesions and the phase of menstrual cycle. METHODS: Surgery was scheduled in the proliferative or secretory phase of the menstrual cycle for 59 women with (n = 35) or without (n = 24) endometriosis. The latter group comprised women undergoing surgery for ovarian cystadenomas. PlGF concentrations in the peritoneal fluid were measured using an enzyme-linked immunosorbent assay. RESULTS: PlGF concentration in the peritoneal fluid was markedly elevated in the endometriosis patients (median 189 pg/ml, interquartile range 84-475 pg/ml) as compared with the controls (88 pg/ml, 41-213 pg/ml; P < 0.001), especially in women with red lesions. Significantly greater values during the secretory phase of the menstrual cycle as compared with the proliferative phase were observed in both the control (cystadenoma) group (P < 0.05) and the endometriosis group (P < 0.001). CONCLUSIONS: Our findings suggest that production of PlGF is sensitive to the cyclic changes in ovarian steroids and may contribute to the pathogenesis of endometriosis, especially that of red lesions, by promoting neovascularization.     

Grading score system: A method for evaluation of the degree of senescence in Senescence Accelerated Mouse (SAM)

For evaluation of the degree of senescence in SAM-P, accelerated senescence prone mouse, formerly called SAM or prone series or P-series, consisting of SAM-P/1, SAM-P/2, SAM-P/3 and SAM-P/4 corresponding to P-1, P-2, P-3 and P-4 series, respectively, in the previous reports, and in SAM-R, accelerated senescence resistant mouse, formerly called resistant series or R-series, consisting of SAM-R/1, SAM-R/2 and SAM-R/3 corresponding to R-1, R-2 and R-3 series, respectively, in the previous reports, the grading score system was adopted. The items to be examined in this system include 11 categories selected from the clinical signs and gross lesions considered to be associated with the aging process. The degree of the senescence in each category was graded from 0 to 4 according to the detailed criteria devised in our laboratory. After 8 months of age each mouse was examined every 4 months, and some of the mice were examined after 2 months of age.In almost all categories, the grading score and incidence began to increase from 4 or 6 months of age and continued to increase with advancing age in both SAM-P and SAM-R. The increase, however, was more marked in SAM-P than in SAM-R. The slow but steady increase in the SAM-R levelled out at 24 months of age and was comparable to that of 12 months of age in SAM-P. In both SAM-P/1 at 8 months of age and SAM-R/2 at 12 months of age, there was a significant reverse correlation between total score of this grading score system and length of residual life after examination.Systematic and extensive studies using the grading score system showed that if the validity of the system is, based on “irreversibility” and “universality” of the changes in     

rRNA gene restriction patterns of Haemophilus influenzae biogroup aegyptius strains associated with Brazilian purpuric fever

The rRNA gene restriction patterns of 92 isolates of Haemophilus influenzae biogroup aegyptius, associated with conjunctivitis or Brazilian purpuric fever in the State of S?o Paulo, Brazil, were studied with 16 + 23S rRNA from Escherichia coli as a probe. All strains were classified into 15 patterns. Isolates from Brazilian purpuric fever cases were seen only in patterns 3 (most frequently) and 4 (rarely), whereas isolates from conjunctivitis were found in all 15 patterns. The study demonstrated that rRNA from E. coli can serve as a probe for molecular epidemiology.     

Melanin biosynthesis inhibitory activity of a compound isolated from young green barley (Hordeum vulgare L.) in B16 melanoma cells

In the course to find compounds that inhibit melanin biosynthesis (i.e., whitening agents), we evaluated the effects of the methanol-soluble fraction (i.e., the water-soluble portion of methanol extracts-CHP20P-MeOH eluted fraction) from young green barley leaves on melanin production in B16 melanoma cells. Activity-guided fractionation led to an isolate called tricin (compound 1) as an inhibitory compound of melanin production in B16 melanoma cells. Furthermore, tricin analogs such as tricetin, tricetin trimethyl ether, luteolin, and apigenin were used for analyzing the structure–activity relationships (SAR) of 5,7-dihydroxyflavones studies. Tricin demonstrated stronger inhibitory activity compared to three other compounds. The results suggest that a hydroxyl group at the C-4′ position and methoxy groups at the C-3′,5′ positions of the tricin skeleton may have important roles in this inhibitory activity in B16 melanoma cells. Our results suggest that tricin inhibits melanin biosynthesis with higher efficacy than arbutin, and it could be used as a whitening agent.