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91.
92.
This study aimed to evaluate the prevalence of sexually transmitted infections (STIs) and associated risk factors in HIV-infected pregnant women followed for prenatal care in Salvador, Bahia. This was a cross-sectional study of 63 women seeking prenatal care at a reference center. Participants were interviewed regarding socio-epidemiological and clinical history, and were tested for HBsAg, anti-HCV, anti HTLV I/II, VDRL, Chlamydia trachomatis, Neisseria gonorrhoeae, Mycoplasma hominis, Ureaplasma urealyticum, CD4 count, and HIV plasma viral load. The main outcome variable was the presence of any STI. The mean age of patients was 28.2 years (16-40 years). 23 (36.5%) were diagnosed with at least one STI. The frequency of diagnoses was: HBV, 3.2%; HCV, 8.1%; HTLV I/II, 3.4%; syphilis, 9.5%; Chlamydia trachomatis, 11.1%; HPV, 15.0%; Mycoplasma hominis, 2.1%, and Ureaplasma urealyticum, 2.1%. No case of Neisseria gonorrhoeae was identified. No association was found between socio-epidemiological variables and the presence of an STI. CD4 T lymphocyte < 500 cells/μL (p = 0.047) and plasma viral load >1,000 copies (p = 0.027) were associated with the presence of STI. STIs are frequent in pregnant women infected with HIV, and all HIV-infected pregnant women should be screened to decrease transmission of these pathogens and to protect their own health.  相似文献   
93.
The aims of the present study were (i) to assess the in vitro genetic stability of S19 and RB51 Brucella abortus vaccines strains and (ii) to evaluate the ability of multiple-locus variable-number tandem repeat (VNTR) analysis (MLVA) as a tool to be used in the quality control of live vaccines against brucellosis. Sixty-three batches of commercial S19 (n = 53) and RB51 (n = 10) vaccines, produced between 2006 and 2009, were used in this study. S19 and RB51 vaccines were obtained from, respectively, seven and two different manufacturers. Ten in vitro serial passages were performed on reference strains and on selected batches of commercial vaccines. All batches, reference strains and strains of serial passages were typed by the MLVA16. The results demonstrated that B. abortus S19 and RB51 vaccine strains are genetically stable and very homogeneous in their respective groups. Anyway, batches of S19 from one manufacturer and batches of RB51 from another presented genotypes distincts from the reference vaccine strains. In both cases, differences were found on locus Bruce07, which had addition of one repeat unit in the case of S19 batches and the deletion of one repeat unit in the case of RB51 batches. In summary, MLVA16 proved to be a molecular tool capable of discriminating small genomic variations and should be included in in vitro official tests.  相似文献   
94.
95.
The objective of this study was to investigate bacterial resistance trends, infection sites and the relationship between resistance and admittance to the intensive care unit (ICU). A total of 53,316 bacteria identified between 1999 and 2008 were evaluated. Multidrug resistance was characterized when gram-negative bacilli (GNB) presented resistance to two or more classes of antibiotics. Gram-positive cocci (CPC) were assessed for resistance to penicillin, oxacillin and vancomycin. GNB were the most common (66.1%) isolate. There was a 3.7-fold overall increase in multidrug resistant GNB over the study period; Acinetobacter baumanii and Staphylococcus aureus were the most prevalent. Highest increases were recorded for Klebsiella pneumoniae (14.6-fold) and enterococci (73-fold). The resistance rates for GNB and GPC were 36% and 51.7%, respectively. Most multidrug resistant GNB and GPC were recovered from ICU patients (p-value < 0.001). Vancomycin-resistant enterococci were isolated during this decade with an increase of 18.7% by 2008. These data confirm the worldwide trend in multidrug bacterial resistance.  相似文献   
96.
Abstract

Protein malnutrition induces structural, neurochemical and functional alterations in the central nervous system, leading to alterations in behavioral function. In order to study the effects of early protein malnutrition on inhibitory avoidance and escape behaviors we used the elevated T-maze (ETM), while the risk assessment behaviors were evaluated by the canopy stretched attend posture (SAP) test. Rat pups were fed by lactating females receiving 16% (control) or 6% (malnourished) protein diets during the lactation period. After weaning the animals received the same diets until 49 days of age, when all animals started receiving a lab chow diet. Behavioral tests were started at 70 days of age. ETM results showed lower inhibitory avoidance in malnourished animals, without differences in escape behavior. SAP test results showed higher exploration and lower risk assessment behaviors in malnourished animals compared to control. These results suggest that malnourished animals are less anxious and/or more impulsive as measured by these two animal models and that malnutrition seems to affect differently behavioral strategies underlying fear and anxiety responses.  相似文献   
97.
The need for daily parenteral administration is an important limitation in the clinical use of pentavalent antimonial drugs against leishmaniasis. In this study, amphiphilic antimony(V) complexes were prepared from alkylmethylglucamides (L8 and L10, with carbon chain lengths of 8 and 10, respectively), and their potential for the oral treatment of visceral leishmaniasis (VL) was evaluated. Complexes of Sb and ligand at 1:3 (SbL8 and SbL10) were obtained from the reaction of antimony(V) with L8 and L10, as evidenced by elemental and electrospray ionization-tandem mass spectrometry (ESI-MS) analyses. Fluorescence probing of hydrophobic environment and negative-staining transmission electron microscopy showed that SbL8 forms kinetically stabilized nanoassemblies in water. Pharmacokinetic studies with mice in which the compound was administered by the oral route at 200 mg of Sb/kg of body weight indicated that the SbL8 complex promoted greater and more sustained Sb levels in serum and liver than the levels obtained for the conventional antimonial drug meglumine antimoniate (Glucantime [Glu]). The efficacy of SbL8 and SbL10 administered by the oral route was evaluated in BALB/c mice infected with Leishmania infantum after a daily dose of 200 mg of Sb/kg for 20 days. Both complexes promoted significant reduction in the liver and spleen parasite burdens in relation to those in the saline-treated control group. The extent of parasite suppression (>99.96%) was similar to that achieved after Glu given intraperitoneally at 80 mg of Sb/kg/day. As expected, there was no significant reduction in the parasitic load in the group treated orally with Glu at 200 mg of Sb/(kg day). In conclusion, amphiphilic antimony(V) complexes emerge as an innovative and promising strategy for the oral treatment of VL.  相似文献   
98.
It has been reported that serine peptidase activities of Trypanosoma cruzi play crucial roles in parasite dissemination and host cell invasion and therefore their inhibition could affect the progress of Chagas disease. The present study investigates the interference of the Stichodactyla helianthus Kunitz-type serine protease inhibitor (ShPI-I), a 55-amino acid peptide, in T. cruzi serine peptidase activities, parasite viability, and parasite morphology. The effect of this peptide was also studied in Leishmania amazonensis promastigotes and it was proved to be a powerful inhibitor of serine proteases activities and the parasite viability. The ultrastructural alterations caused by ShPI-I included vesiculation of the flagellar pocket membrane and the appearance of a cytoplasmic vesicle that resembles an autophagic vacuole. ShPI-I, which showed itself to be an important T. cruzi serine peptidase inhibitor, reduced the parasite viability, in a dose and time dependent manner. The maximum effect of peptide on T. cruzi viability was observed when ShPI-I at 1 × 10−5 M was incubated for 24 and 48 h which killed completely both metacyclic trypomastigote and epimastigote forms. At 1 × 10−6 M ShPI-I, in the same periods of time, reduced parasite viability about 91–95% respectively. Ultrastructural analysis demonstrated the formation of concentric membranar structures especially in the cytosol, involving organelles and small vesicles. Profiles of endoplasmic reticulum were also detected, surrounding cytosolic vesicles that resembled autophagic vacuoles. These results suggest that serine peptidases are important in T. cruzi physiology since the inhibition of their activity killed parasites in vitro as well as inducing important morphological alterations. Protease inhibitors thus appear to have a potential role as anti-trypanosomatidal agents.  相似文献   
99.
The phylogenetic relationships among species of Triatoma matogrossensis subcomplex (T. baratai, T. guazu, T. matogrossensis, T. sordida, T. vandae, and T. williami) was addressed by using fragments of cytochrome oxidase I (COI), 16S rDNA (16S), and cytochrome b (Cytb) through Bayesian and parsimony analyses. We did not recover a monophyletic T. matogrossensis subcomplex, and their members were found clustered in three strongly supported clades, as follows: i) T. jurbergi + T. matogrossensis + T. vandae + T. garciabesi + T. sordida; ii) with T. guasayana as the sister group of clade (i); and iii) T. williami + T. guazu, however not closely related to the clade formed by the previously mentioned species. The other two endemic species from Central-Western Brazil, T. baratai and T. costalimai, were not recovered with strong clade support as related to other members of this subcomplex. Results call for a further revision in the classification of the subcomplexes within the genus Triatoma.  相似文献   
100.
Objective: Describe the use of assistive technology to enhance communication opportunities for older adults.

Methods: A systematic review was conducted in two databases, PubMed and Web of Science, by using two different searches in each. The search was limited to original articles, in English language, including people aged 60 years and older that used any type of assistive technology for communication. The articles found in the initial search were filtered by title, abstracts and the remaining articles were fully read.

Results: Eighteen studies were included in this review after the reading of full-texts. Most of the studies included apparently healthy participants with communication limitations due to aging related changes and the others included people with some pathology that prevent them from normal communication.

Conclusion: Four categories of assistive technology were identified: assistive technology for people with speech problems; robot or videoconferencing systems; Information and Communication Technologies and, other types of assistive technology for communication, such as hearing aids and scrapbooks. Assistive technology for communication of older adults is not only used by people with disabilities that prevent them from usual communication. They are mostly for older adults without a pathological communication problem.  相似文献   

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