Evaluation of antibacterial, antifungal and modulatory activity of methanol and ethanol extracts of Padina sanctae-crucis

Background: Multi-resistant microorganisms such as Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Candida tropicalis e Candida krusei are the main causes of microbial infections. Padina sanctae-crucis is a seaweed often used to check the contamination of ecosystems by materials such as heavy metals, but studies of the antimicrobial activity of the same seaweed were not found.Methods: The tests for the minimum inhibitory concentration and   modulation of microbial resistance, with the use of ethanolic and  methanolic extracts of Padina Sanctae-cruces combined with drugs of the class of aminoglycosides and antifungal were used to evaluate the activity against the cited microorganisms.Results: Was observed a modulation of antibiotic activity between the natural products and the E. coli and S. aureus strains, indicating a synergism and antagonism respectively.Conclusions: The results showed a moderate modulatory effect against some microorganisms studied.Keywords: multi-resistant microorganisms, modulation, Padina Sanctae-crucis, antimicrobial activity

Phylogenetic reconstruction of dengue virus type 2 in Colombia

Background: Dengue fever is perhaps the most important viral re-emergent disease especially in tropical and subtropical countries, affecting about 50 million people around the world yearly. In Colombia, dengue virus was first detected in 1971 and still remains as a major public health issue. Although four viral serotypes have been recurrently identified, dengue virus type 2 (DENV-2) has been involved in the most important outbreaks during the last 20 years, including 2010 when the fatality rate highly increased. As there are no major studies reviewing virus origin and genotype distribution in this country, the present study attempts to reconstruct the phylogenetic history of DENV-2 using a sequence analysis from a 224 bp PCR-amplified product corresponding to the carboxyl terminus of the envelope (E) gene from 48 Colombian isolates. Results: As expected, the oldest isolates belonged to the American genotype (subtype V), but the strains collected since 1990 represent the American/Asian genotype (subtype IIIb) as previously reported in different American countries. Interestingly, the introduction of this genotype coincides with the first report of dengue hemorrhagic fever in Colombia at the end of 1989 and the increase of cases during the next years. Conclusion: After replacement of the American genotype, several lineages of American/Asian subtype have rapidly spread all over the country evolving in new clades. Nevertheless, the direct association of these new variants in the raise of lethality rate observed during the last outbreak has to be demonstrated

Phylogenetic history demonstrates two different lineages of dengue type 1 virus in Colombia

Background: Dengue Fever is one of the most important viral re-emergent diseases affecting about 50 million people around the world especially in tropical and sub-tropical countries. In Colombia, the virus was first detected in the earliest 70′s when the disease became a major public health concern. Since then, all four serotypes of the virus have been reported. Although most of the huge outbreaks reported in this country have involved dengue virus serotype 1 (DENV-1), there are not studies about its origin, genetic diversity and distribution. Results: We used 224 bp corresponding to the carboxyl terminus of envelope (E) gene from 74 Colombian isolates in order to reconstruct phylogenetic relationships and to estimate time divergences. Analyzed DENV-1 Colombian isolates belonged to the formerly defined genotype V. Only one virus isolate was clasified in the genotype I, likely representing a sole introduction that did not spread. The oldest strains were closely related to those detected for the first time in America in 1977 from the Caribbean and were detected for two years until their disappearance about six years later. Around 1987, a split up generated 2 lineages that have been evolving separately, although not major aminoacid changes in the analyzed region were found. Conclusion: DENV-1 has been circulating since 1978 in Colombia. Yet, the phylogenetic relationships between strains isolated along the covered period of time suggests that viral strains detected in some years, although belonging to the same genotype V, have different recent origins corresponding to multiple re-introduction events of viral strains that were circulating in neighbor countries. Viral strains used in the present study did not form a monophyletic group, which is evidence of a polyphyletic origin. We report the rapid spread patterns and high evolution rate of the different DENV-1 lineages

Genome of the Avirulent Human-Infective Trypanosome—Trypanosoma rangeli

Background: Trypanosoma rangeli is a hemoflagellate protozoan parasite infecting humans and other wild and domestic mammals across Central and South America. It does not cause human disease, but it can be mistaken for the etiologic agent of Chagas disease, Trypanosoma cruzi. We have sequenced the T. rangeli genome to provide new tools for elucidating the distinct and intriguing biology of this species and the key pathways related to interaction with its arthropod and mammalian hosts.  Methodology/Principal Findings: The T. rangeli haploid genome is ,24 Mb in length, and is the smallest and least repetitive trypanosomatid genome sequenced thus far. This parasite genome has shorter subtelomeric sequences compared to those of T. cruzi and T. brucei; displays intraspecific karyotype variability and lacks minichromosomes. Of the predicted 7,613 protein coding sequences, functional annotations could be determined for 2,415, while 5,043 are hypothetical proteins, some with evidence of protein expression. 7,101 genes (93%) are shared with other trypanosomatids that infect humans. An ortholog of the dcl2 gene involved in the T. brucei RNAi pathway was found in T. rangeli, but the RNAi machinery is non-functional since the other genes in this pathway are pseudogenized. T. rangeli is highly susceptible to oxidative stress, a phenotype that may be explained by a smaller number of anti-oxidant defense enzymes and heatshock proteins.  Conclusions/Significance: Phylogenetic comparison of nuclear and mitochondrial genes indicates that T. rangeli and T. cruzi are equidistant from T. brucei. In addition to revealing new aspects of trypanosome co-evolution within the vertebrate and invertebrate hosts, comparative genomic analysis with pathogenic trypanosomatids provides valuable new information that can be further explored with the aim of developing better diagnostic tools and/or therapeutic targets

The 3′ UTR Variants in the GRP78 Are Not Associated with Overall Survival in Resectable Hepatocellular Carcinoma

Background: Elevated glucose-regulated protein 78 (GRP78) levels in tissues have been known to be related with poor prognosis in hepatocellular carcinoma (HCC) patients. Though the variants in the 3′ untranslated region (UTR) of GRP78 gene were not associated with HCC risk, we wonder whether these polymorphisms affect survival of HCC patients. Methodology/Principal Findings: Blood samples of HCC patients were maintained in our specimen bank between 1996 to 2003. DNA from 576 unrelated and resectable patients with HCC was typed for rs16927997 (T>C), rs1140763 (T>C) and rs12009 (T>C) by TaqMan assays. The Kaplan-Meier method and log-rank test were used to estimate overall survival. Linkage disequilibrium (LD) analysis identified a total of 3 haplotypes and 6 diplotypes in this region. The distribution of haplotype was not related to the clinical characteristics. Univariate analysis showed that the allele, genotype, haplotype and diplotype did not effect the survival. None of the clinical features show a significant association (P correced>0.05) with overall patient outcome in multiple comparisons. Conclusions/Significance: There is no noteworthy influence of 3′ UTR variants in the GRP78 on prognosis of resectable HCC in the Chinese population. © 2011 Zhu et al.published_or_final_versio