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941.
942.
Length‐weight relationships for 15 fish species from Atlantic rain forest streams,southeastern Brazil 下载免费PDF全文
M. R. da Costa T. Moreti W. Uehara H. K. dos Santos F. G. Araújo 《Zeitschrift fur angewandte Ichthyologie》2015,31(4):809-810
Length‐weight relationships were determined for 15 fish species from the tributary Atlantic rain forest steams that drain into Sepetiba Bay, southeastern Brazil. This is the first record of length‐weight relationships for 12 of these species and new maximum lengths for four species. These results will be useful for management and conservation of this area of the Atlantic rain forest drainages. 相似文献
943.
Alfredo?Santos Xavier?Guimerà Antonio?David?Dorado Xavier?Gamisans David?GabrielEmail author 《Applied microbiology and biotechnology》2015,99(1):67-76
The purpose of this work was to evaluate the technical and economical feasibility of converting three chemical scrubbers in series to biotrickling filters (BTFs) for the simultaneous removal of H2S and volatile organic compounds (VOCs). The conversion of the full-scale scrubbers was based on previous conversion protocols. Conversion mainly required replacing the original carrier material and recycle pumps as well as modifying the controls and operation of the reactors. Complete removal of H2S and VOCs on a routine basis was reached at neutral pH in a longer period of time compared to previous conversions reported. Biotrickling filters operated at a gas contact time of about 1.4 s per reactor and at pH controlled between 6.5 and 6.8. Inlet average concentrations below 10 ppmv of H2S and below 5 ppmv for VOCs were often completely removed. The first and second bioreactors played a primary role in H2S removal. Year-round operation of the biotrickling filters proved the ability of the system to handle progressive load increases of H2S and VOCs. However, fast, sudden load changes often lead to reduced removal efficiencies. Odor analyses showed average removal efficiencies above 80 %. Gas chromatography-mass spectrometry of selected samples showed that outlet odor concentration was due to limited removal of VOCs. The conversion showed was economically viable taking into account the theoretical consumption of chemicals needed for the absorption and oxidation of both H2S and VOCs. 相似文献
944.
945.
Paulo FP Pimenta Alessandra S Orfano Ana C Bahia Ana PM Duarte Claudia M Ríos-Velásquez Fabrício F Melo Felipe AC Pessoa Giselle A Oliveira Keillen MM Campos Luis Martínez Villegas Nilton Barnabé Rodrigues Rafael Nacif-Pimenta Rejane C Sim?es Wuelton M Monteiro Rogerio Amino Yara M Traub-Cseko José BP Lima Maria GV Barbosa Marcus VG Lacerda Wanderli P Tadei Nágila FC Secundino 《Memórias do Instituto Oswaldo Cruz》2015,110(1):23-47
In the Americas, areas with a high risk of malaria transmission are mainly located in
the Amazon Forest, which extends across nine countries. One keystone step to
understanding the Plasmodium life cycle in Anopheles species from the Amazon Region
is to obtain experimentally infected mosquito vectors. Several attempts to colonise
Ano- pheles species have been conducted, but with only short-lived success or no
success at all. In this review, we review the literature on malaria transmission from
the perspective of its Amazon vectors. Currently, it is possible to develop
experimental Plasmodium vivax infection of the colonised and field-captured vectors
in laboratories located close to Amazonian endemic areas. We are also reviewing
studies related to the immune response to P. vivax infection of Anopheles aquasalis,
a coastal mosquito species. Finally, we discuss the importance of the modulation of
Plasmodium infection by the vector microbiota and also consider the anopheline
genomes. The establishment of experimental mosquito infections with Plasmodium
falciparum, Plasmodium yoelii and Plasmodium berghei parasites that could provide
interesting models for studying malaria in the Amazonian scenario is important.
Understanding the molecular mechanisms involved in the development of the parasites
in New World vectors is crucial in order to better determine the interaction process
and vectorial competence. 相似文献
946.
Miriam YH Ueda Paulo G Alvarenga Juliana M Real Eloisa de Sá Moreira Aripuan? Watanabe Ana Maria Passos-Castilho Matheus Vescovi Yana Novis Vanderson Rocha Adriana Seber Jose SR Oliveira Celso A Rodrigues Celso FH Granato 《Memórias do Instituto Oswaldo Cruz》2015,110(4):461-467
Human herpesvirus 6 (HHV-6) may cause severe complications after haematopoietic stem
cell transplantation (HSCT). Monitoring this virus and providing precise, rapid and
early diagnosis of related clinical diseases, constitute essential measures to
improve outcomes. A prospective survey on the incidence and clinical features of
HHV-6 infections after HSCT has not yet been conducted in Brazilian patients and the
impact of this infection on HSCT outcome remains unclear. A rapid test based on
real-time quantitative polymerase chain reaction (qPCR) has been optimised to screen
and quantify clinical samples for HHV-6. The detection step was based on reaction
with TaqMan® hydrolysis probes. A set of previously described primers and
probes have been tested to evaluate efficiency, sensitivity and reproducibility. The
target efficiency range was 91.4% with linearity ranging from 10-106
copies/reaction and a limit of detection of five copies/reaction or 250 copies/mL of
plasma. The qPCR assay developed in the present study was simple, rapid and
sensitive, allowing the detection of a wide range of HHV-6 loads. In conclusion, this
test may be useful as a practical tool to help elucidate the clinical relevance of
HHV-6 infection and reactivation in different scenarios and to determine the need for
surveillance. 相似文献
947.
Evaluation of blood pressure in feline night monkeys (Aotus azarae infulatus) under different restraint protocols 下载免费PDF全文
948.
Maria C Anholeti Rodrigo C Duprat Maria R Figueiredo Maria AC Kaplan Marcelo Guerra Santos Marcelo S Gonzalez Norman A Ratcliffe Denise Feder Selma R Paiva Cicero B Mello 《Memórias do Instituto Oswaldo Cruz》2015,110(5):629-635
Studies evaluated the effects of hexanic extracts from the fruits and flowers
ofClusia fluminensis and the main component of the flower
extract, a purified benzophenone (clusianone), against Aedes
aegypti. The treatment of larvae with the crude fruit or flower extracts
from C. fluminensis did not affect the survival ofAe.
aegypti (50 mg/L), however, the flower extracts significantly delayed
development of Ae. aegypti. In contrast, the clusianone (50 mg/L) isolate from the
flower extract, representing 54.85% of this sample composition, showed a highly
significant inhibition of survival, killing 93.3% of the larvae and completely
blocking development of Ae. aegypti. The results showed, for the first time, high
activity of clusianone against Ae. aegypti that both killed and inhibited mosquito
development. Therefore, clusianone has potential for development as a biopesticide
for controlling insect vectors of tropical diseases. Future work will elucidate the
mode of action of clusianone isolated from C. fluminensis. 相似文献
949.
Louisy Sanches dos Santos Camila Azevedo Antunes Cintia Silva dos Santos José Augusto Adler Pereira Priscila Soares Sabbadini Maria das Gra?as de Luna Vasco Azevedo Raphael Hirata Júnior Andreas Burkovski Lídia Maria Buarque de Oliveira Asad Ana Luíza Mattos-Guaraldi 《Memórias do Instituto Oswaldo Cruz》2015,110(5):662-668
Corynebacterium diphtheriae, the aetiologic agent of diphtheria,
also represents a global medical challenge because of the existence of invasive
strains as causative agents of systemic infections. Although tellurite
(TeO32-) is toxic to most microorganisms, TeO32--resistant
bacteria, including C. diphtheriae, exist in
nature. The presence of TeO32--resistance (TeR)
determinants in pathogenic bacteria might provide selective advantages in the natural
environment. In the present study, we investigated the role of the putative
TeR determinant (CDCE8392_813gene) in the virulence
attributes of diphtheria bacilli. The disruption of CDCE8392_0813 gene expression in
the LDCIC-L1 mutant increased susceptibility to TeO32- and reactive oxygen
species (hydrogen peroxide), but not to other antimicrobial agents. The LDCIC-L1
mutant also showed a decrease in both the lethality of Caenorhabditis elegans
and the survival inside of human epithelial cells compared to wild-type
strain. Conversely, the haemagglutinating activity and adherence to and formation of
biofilms on different abiotic surfaces were not regulated through the CDCE8392_0813
gene. In conclusion, the CDCE8392_813 gene contributes to the TeR and
pathogenic potential of C. diphtheriae. 相似文献
950.
Jefferson José da Silva Santos Tereza Magalh?es José Valter Joaquim Silva Junior Andréa Nazaré Monteiro Rangel da Silva Marli Tenório Cordeiro Laura Helena Vega Gonzales Gil 《Memórias do Instituto Oswaldo Cruz》2015,110(5):677-683
Full-length dengue virus (DENV) cDNA clones are an invaluable tool for many studies,
including those on the development of attenuated or chimeric vaccines and on
host-virus interactions. Furthermore, the importance of low passage DENV infectious
clones should be highlighted, as these may harbour critical and unique
strain-specific viral components from field-circulating isolates. The successful
construction of a functional Brazilian low passage DENV serotype 2 full-length clone
through homologous recombination reported here supports the use of a strategy that
has been shown to be highly useful by our group for the development of flavivirus
infectious clones and replicons. 相似文献