Factors associated with non-completion of latent tuberculosis infection treatment in Rio de Janeiro, Brazil: A non-matched case control study.

INTRODUCTION: There are scarce data on the routine latent tuberculosis infection treatment (LTBIT) and factors associated with a non-completion in high tuberculosis burden countries. Therefore, in this study we aimed to evaluate the factors associated with non-completion of LTBIT. MATERIALS AND METHODS: This was a non-matched case control study conducted at a University Hospital in Rio de Janeiro, Brazil. A total of 114 cases and 404 controls were enrolled between January/1999 and December/2009. Cases were close contacts who did not complete the LTBIT and controls were the contacts that completed it. Multivariate analysis was used to investigate risk factors associated with non-completion of LTBIT among contacts in two different periods of recruitment. RESULTS: Factors associated with non-completion LTBIT included: drug use (OR 23.33, 95% CI 1.83-296.1), TB treatment default by the index case (OR 16.97, 95% CI 3.63-79.24) and drug intolerance. TB disease rates after two years of follow up varied from 0.4% to 1.9%. The number necessary to treat to prevent one TB case among contacts was 116. CONCLUSIONS: Non-completion treatment by the index case and illicit drug use were associated with not completing latent tuberculosis infection treatment and no tuberculosis disease was identified among those who completed latent tuberculosis infection treatment.

Ligand Exchange Reaction of Au(I) R-N-Heterocyclic Carbene Complexes with Cysteine.

The chemotherapy with gold complexes has been attempted since the 90s after the clinical success of auranofin, a gold(I) coordination complex. Currently, the organometallics compounds have shown promise in cancer therapy, mainly in those complexes containing N-heterocylic carbenes (NHC) as a ligand. The present study shows a kinetic analysis of the reaction of six alkyl-substituted NHC with cysteine (Cys), which is taken as an important bionucleophile representative. The first and second ligand exchange processes were analyzed with the complete description of the mechanism and energy profiles. For the first reaction step, which is the rate-limiting step of the whole substitution reaction, the activation enthalpy follows the order 1/Me2 < 2/Me,Et < 4/n-Bu2 < 3/i-Pr2 < 6/Cy2 < 5/t-Bu2, which is fully explained by steric and electronic features. From a steric point of view, the previous reactivity order is correlated with the r(Au-S) calculated for the transition state structures where S is the sulfur ligand from the Cys entering group. This means that longer r(Au-S) leads to higher activation enthalpy and is consistent with the effectiveness of gold shielding from nucleophile attack by bulkier alkyl-substituted NHC ligand. When electronic effect was addressed we found that higher activation barrier was predicted for strongly electron-donating NHC ligand, represented by the eigenvalue of σ-HOMO orbital of the free ligands. The molecular interpretation of the electronic effects is that strong donating NHC forms strong metal-ligand bond. For the second reaction step, similar structure-reactivity relationships were obtained, however the activation energies are less sensitive to the structure.

New loci of Lychnophora ericoides and transferability to Lychnophora pinaster, endangered medicinal species from Brazil.

Lychnophora ericoides and Lychnophora pinaster are species used in popular medicine as analgesic or anti-inflammatory agents to treat contusions, rheumatism, and insect bites. In this study, 21 simple sequence repeat loci of L. ericoides were developed and transferred to L. pinaster. Three populations of L. ericoides and 2 populations of L. pinaster were evaluated; they were collected in the State of Minas Gerais. Population parameters were estimated, and the mean values of observed and expected heterozygosity were 0.297 and 0.408 (L. ericoides) and 0.228 and 0.310 (L. pinaster), respectively. Greater genetic variability was observed within populations than between populations of L. ericoides (62 and 37%) and L. pinaster (97 and 2.8%). These results provide information for genetic conservation and taxonomic studies of these endangered species.

Seminal plasma concentrations of Anti-Müllerian hormone and inhibin B predict motile sperm recovery from cryopreserved semen in asthenozoospermic men: a prospective cohort study.

The rate of motile sperm recovery after cryopreservation is very variable and difficult to predict. Anti-Müllerian hormone (AMH) and inhibin B are produced by Sertoli cells and released into the seminal plasma, where they could be functional markers of spermatogenesis and sperm resistance to thermal stress. The aim of this study was to evaluate whether seminal plasma levels of AMH and inhibin B predict sperm recovery after cryopreservation. The study included 153 men enrolled prospectively during a semen analysis. The cohort was stratified by the fresh semen characteristics into: normal (n = 52), high sperm count (n = 55), asthenozoospermia (n = 23), and oligozoospermia (n = 23). The main outcome measure was motile sperm recovery rate, defined as post-thaw total motile sperm count × 100/pre-freezing total motile sperm count. In men with asthenozoospermia there was a significant correlation between motile sperm recovery rate and the pre-freezing concentrations of AMH (r = 0.522, p < 0.05) and inhibin B (0.471, p < 0.05). In this group, the areas under the receiver operating characteristic curves of AMH and inhibin B for prediction of ≥50% motile sperm recovery after cryopreservation were, respectively, 0.808 and 0.638. AMH was particularly useful, with sensitivity of 0.85, specificity of 0.80, positive predictive value of 0.84 and negative predictive value of 0.80. The sensitivity, specificity, positive, and negative predictive values of inhibin B for the same outcome were, respectively, 0.62, 0.60, 0.67, and 0.55. The median motile sperm recovery rate was 83% when seminal plasma AMH concentration was ≥0.84 ng/mL, vs. 27% when AMH concentration was <0.84 ng/mL (p < 0.05). In other patient groups, there was no correlation between the two hormone levels in seminal plasma and the motile sperm recovery rate. In conclusion, seminal plasma AMH and inhibin B concentrations correlate with and can be used to predict motile sperm recovery after semen cryopreservation in asthenozoospermic men.

Characterization and anti-staphylococcal activity of the essential oil from Turnera subulata Sm

The present study is pioneer in analyzing the chemical composition of the essential oil from aerial parts of Turnera subulata Sm. and evaluates their antibacterial activity against a panel of drug-resistant strains of Staphylococcus aureus. The aerial parts were kiln-dried and then powdered in mechanical mill, and was subjected to hydrodistillation in a Clevenger-type apparatus. The components were analyzed using a mass spectrometrycoupled gas chromatography (GC-MS), and the identification of substances was performed by comparison of the mass spectra obtained with the mass spectra of the database of the GC-MS and retention indices . The essential oil was evaluated using the method of broth dilution at concentrations ranging from 3.125µg/mL to 3200µg/mL. It was possible to identify 45 substances (92.1%) of the essential oils, and the major components were trans-caryophyllene (6.7%), citronellol (5.6%), sphatulenol (5.3%), α-cadinol (4.3%), n-tricosano (4.3%), geraniol (4.1%) and trans-geranilacetone (3.7%), n-pentacosano (3.5%), globulol (3.4%), caryophyllene oxide (3.2%). The essential oil of T. subulata Sm. showed effective antibacterial activity for the various strains of S. aureus tested, with the MIC values between 25 µg/mL and 1600 µg/mL. The study of the essential oil of Turnera subulata Sm. showed that it consists of a complex mixture of several classes of compounds having the sesquiterpenes as major constituents followed by monoterpenes, and showed an antibacterial activity significant front the strains tested.

O presente estudo é pioneiro em analisar a composição química dos óleos essenciais das partes aéreas de Turnera subulata Sm. e sua atividade antibacteriana frente à Staphylococcus aureus resistentes a antibióticos. As partes aéreas da planta foram secas em estufa, pulverizadas em moinho mecânico e submetidas à hidrodestilaçao em aparato tipo Clevenger. A composição dos óleos essenciais foi analisada por cromatografia gasosa acoplada a espectrometria de massas (CG-EM), e a identificação realizada por comparação dos espectros de massas com a biblioteca do CG-EM e índices de retenção. A atividade antimicrobiana do óleo essencial foi avaliada usando o método de diluição em caldo, em concentrações que variaram de 3.125µg/mL to 3200µg/mL. Foi possível identificar 45 substâncias (92,1%) do óleo essencial, sendo os componentes majoritários: trans-cariofileno (6,7%), citronelol (5,6%), espatulenol (5,3%), α-cadinol (4,3%), n-tricosano (4,3%), geraniol (4,1%) e trans-geranilacetona (3,7%), n-pentacosano (3,5%), globulol (3,4%) e óxido de cariofileno (3,2%). O óleo essencial de T. subulata Sm. mostrou atividade antibacteriana eficaz para as várias cepas de S. aureus testadas, com valores de CIM entre 25 µg/mL e 1600 µg/mL. O estudo do óleo essencial de Turnera subulata Sm. evidenciou sua complexa mistura, contendo várias classes de substâncias, tendo os sesquiterpenos como constituintes majoritários seguido dos monoterpenos, e mostrou significativa atividade antibacteriana frente as cepas testadas.

Results of implementation of preventive recommendations for tuberculosis after renal transplantation in an endemic area.

This retrospective cohort study assessed the results of the implementation of preventive recommendations for tuberculosis (TB) among renal transplant recipients in an endemic area (Rio de Janeiro, Brazil). Subjects were defined as at high risk for TB if they had latent tuberculosis infection (LTBI), reported recent close contact with individuals with TB or received a graft from a donor with LTBI. A 6-month course of isoniazid preventive therapy (IPT) was targeted to high-risk subjects. The study end point was TB confirmed by culture. Altogether, 535 patients were included. Median follow-up was 59 months. The overall cumulative incidence of TB was 2.1% while among the 274 patients in whom the preventive protocol was fully implemented, the incidence was only 0.7%. The incidence of TB among 75 high-risk recipients not treated with isoniazid (7%) was significantly higher than that observed in 209 untreated low-risk patients (1%, p = 0.006) and in 65 high-risk subjects that received IPT (no case, p = 0.03). In conclusion, the implementation of preventive recommendations for TB in an endemic area allowed the appropriate discrimination between high- and low-risk renal transplant recipients and was associated with long-term reduction in the incidence of this complication among high-risk subjects.

Multilayer architectures based on a-SiC:H material: tunable wavelength filters in optical processing devices.

The characteristics of tunable wavelength filters based on a-SiC:H multilayered stacked pin cells are studied both theoretically and experimentally. The optical transducers were produced by PECVD and tested for a proper fine tuning of the cyan and yellow fluorescent proteins emission. The active device consists of a p-i'(a-SiC:H)-n/p-i(a-Si:H)-n heterostructures sandwiched between two transparent contacts. Experimental data on spectral response analysis, current-voltage characteristics and color and transmission rate discrimination are reported. Cyan and yellow fluorescent input channels were transmitted together, each one with a specific transmission rate and different intensities. The multiplexed optical signal was analyzed by reading out, under positive and negative applied voltages, the generated photocurrents. Results show that the optimized optical transducer has the capability of combining the transient fluorescent signals onto a single output signal without losing any specificity (color and intensity). It acts as a voltage controlled optical filter: when the applied voltages are chosen appropriately the transducer can select separately the cyan and yellow channel emissions (wavelength and frequency) and also to quantify their relative intensities. A theoretical analysis supported by a numerical simulation is presented.

Semiconductor device as optical demultiplexer for short range optical communications.

In this paper we present results on the use of a multilayered a-SiC:H heterostructure as a wavelength-division demultiplexing device for the visible light spectrum. The proposed device is composed of two stacked p-i-n photodiodes with intrinsic absorber regions adjusted to short and long wavelength absorption and carrier collection. An optoelectronic characterisation of the device was performed in the visible spectrum. Demonstration of the device functionality for WDM applications was done with three different input channels covering the long, the medium and the short wavelengths in the visible range. The recovery of the input channels is explained using the photo-current spectral dependence on the applied voltage. An electrical model of the WDM device is proposed and supported by the solution of the respective circuit equations. Short range optical communications constitute the major application field, however other applications are also foreseen.

Detection of change in fluorescence between reactive cyan and the yellow fluorophores using a-SiC:H multilayer transducers.

Optical colour sensors based on multilayered a-SiC:H heterostructures can act as voltage controlled optical filters in the visible range. In this article we investigate the application of these structures for Fluorescence Resonance Energy Transfer (FRET) detection, The characteristics of a-SiC:H multilayered structure are studied both theoretically and experimentally in several wavelengths corresponding to different fluorophores. The tunable optical p-i'(a-SiC:H)-n/p-i(a-Si:H)-n heterostructures were produced by PECVD and tested for a proper fine tuning in the violet, cyan and yellow wavelengths. The devices were characterized through transmittance and spectral response measurements, under different electrical bias and frequencies. Violet, cyan and yellow signals were applied in simultaneous and results have shown that they can be recovered under suitable applied bias. A theoretical analysis supported by numerical simulation is presented.

Prevalence of anti-tuberculosis drug resistance in an HIV/AIDS reference hospital in Rio de Janeiro, Brazil.

SETTING: A reference hospital for tuberculosis (TB) and human immunodeficiency virus/acquired immune-deficiency syndrome (HIV/AIDS) with a TB control programme in Rio de Janeiro, Brazil. OBJECTIVE: To estimate the prevalence of resistance to anti-tuberculosis drugs and to identify associated factors. DESIGN: In a cross-sectional study, clinical and laboratory data were collected retrospectively from 2001 to 2005. Patients with isolation of Mycobacterium tuberculosis and available drug susceptibility tests were considered eligible. Data on demographic characteristics, risk factors for resistance, HIV serology and past TB history were collected and analysed by chi(2) Mann-Whitney test and Poisson regression. RESULTS: We analysed 350 treatments, of which 62 were for patients with previous TB. HIV status was positive in 31.2% of cases. Resistance was found in 15.7% and multidrug resistance (MDR) in 4.3% of cases. Previous treatment (P < 0.001) and relapse within 2 years were associated with resistance (P < 0.03). Pulmonary cavities were associated with MDR (P < 0.001). Homelessness was associated with any resistance in newly diagnosed patients (P < 0.01). Working in a hospital was not associated with resistance. CONCLUSION: Suspicion of drug-resistant disease is necessary in patients with a history of previous TB in hospitals in Rio de Janeiro. The implementation of an effective hospital TB control programme can prevent transmission even in high TB prevalence settings.

Cassava starch fermentation wastewater: characterization and preliminary toxicological studies.

Cassava starch fermentation wastewater is an industrial residue composed mainly of lactic acid bacteria with predominance of the genera Lactobacillus, and organic acids. To evaluate the safety of this residue for possible production of probiotic beverages, acute in mice and sub-chronic (28-day repeated dose) toxicity studies in rats were carried. The administration of a single dose of 5 g/kg/body weight did not produce mortality in mice. Rats treated with water containing 0 (control), 25%, 50%, and 100% of the residue for 28 days, did not present alterations in behaviour or in food and water consumption. There were no treatment-related changes of toxicological significance in the relative weight of the organs neither in the haematological nor in the biochemical parameters. Histopathologic alterations observed in the small intestine did not seem to be associated with the treatment.

Serotypes and virulence markers of Shiga toxin-producing Escherichia coli (STEC) isolated from dairy cattle in São Paulo State, Brazil.

In order to determine the occurrence, serotypes and virulence markers of Shiga toxin-producing Escherichia coli (STEC) strains, 153 fecal samples of cattle randomly selected from six dairy farms in Sao Paulo State, Brazil, were examined for Shiga toxin (Stx) production by the Vero cell assay. Feces were directly streaked onto MacConkey Sorbitol Agar and incubated at 37 degrees C overnight. Sorbitol-negative colonies (maximum 20) and up to 10 sorbitol-positive colonies from each plate were subcultured onto presumptive diagnostic medium IAL. Sorbitol-negative isolates were screened with O157 antiserum for identification of O157:H7 E. coli. Isolates presenting cytotoxic activity were submitted to colony hybridization assays with specific DNA probes for stx1, stx2, eae, Ehly and astA genes. The isolation rate of STEC ranged from 3.8 to 84.6% depending on the farm analysed. STEC was identified in 25.5% of the animals, and most of them (64.1%) carried a single STEC serotype. A total of 202 STEC isolates were recovered from the animals, and except for the 2 O157:H7 isolates all the others expressed cytotoxic activity. The great majority of the STEC isolates carried both stx1 and stx2 genes (114/202, 56.4%) or stx2 (82/202, 40.6%); and whereas the Ehly sequence occurred in most of them (88%) eae was only observed in O157:H7 and O111:HNM isolates. Serotypes O113:H21, O178:H19 and O79:H14 were the most frequent STEC serotypes identified and widely distributed among animals from different farms, while others such as O77:H18, O88:H25 and O98:H17 occurred only in particular farms. This is the first report on the occurrence of STEC in dairy cattle in Sao Paulo State, and the results point to substantial differences in rate of isolation, serotypes and genetic profile of STEC that has been previously described among beef cattle in our community. Moreover, to our knowledge O79:H14 and O98:H17 represent new STEC serotypes, while O178:H19 has only been recently reported in Spain.

Frequency and characteristics of diarrhoeagenic Escherichia coli strains isolated from children with and without diarrhoea in Rio de Janeiro, Brazil.

The frequency of diarrhoeagenic Escherichia coli (DEC) strains was investigated in 253 children up to 3 years old, with (patient group, PG, 199 children) and without (control group, CG, 54 children) diarrhoea, living in Rio de Janeiro, Brazil. DEC strains were detected in 70 (27.6%) children, including 54 (27.1%) with diarrhoea and 16 (29.6%) without diarrhoea. Enteroaggregative E. coli (EAEC) was the most frequent DEC category, accounting for 14.6% of the isolates in the PG and for 11.1% in the CG. E. coli strains carrying enteropathogenic E. coli (EPEC) virulence markers showed higher incidence in the CG (12.9%) than in the PG (8.0%). E. coli strains belonging to non-classical EPEC groups that carried eae only or eae and bfpA, designated as attaching-effacing E. coli (AEEC) were the most frequent (79.1%). Simultaneous presence of multiple EPEC virulence factors (EAF/eae/bfpA) were only detected among strains isolated from the PG. Enterotoxigenic E. coli (ETEC) strains were isolated from 5.5% of the children in the CG and from 3.5% of those in the PG. Most of the ETEC isolates were LT-probe positive (70%) and none carried both LT-I and ST-I probe sequences. One enteroinvasive E. coli (EIEC) strain was recovered from a child with diarrhoea. No stx-probe positive E. coli strains were detected. Overall, DEC strains were not found to be significantly associated with diarrhoea (p>0.05). However, the higher incidence of EAEC, the most frequent DEC category, among children with diarrhoea, suggests a potential role of EAEC as an important enteric pathogen in the community investigated.

Renal artery aneurysm in hand-assisted laparoscopic donor nephrectomy: case report.

We report a living donor who underwent laparoscopic nephrectomy using a hand-assisted device (HALD). At preoperative arteriography the donor showed a renal artery aneurysm. The patient was a 37-year-old female, 166 cm height, white, weighing 87 kg, HLA identical to the recipient. HALD was indicated due to the better visualization of renal pedicle and greater security in an obese patient. Renal artery aneurysm is a rare condition, with many possible complications. The method proved to be adequate and safe for donor nephrectomy, despite a renal artery aneurysm.

Metabolism of phenylpropionic acid in enteropathogenic Escherichia coli belonging to serogroup O111 and its application for diagnosis.

We evaluated a biochemical assay based on the ability to metabolise beta-phenylpropionic acid (PPA) as a diagnostic aid in the identification of typical enteropathogenic Escherichia coli (EPEC) strains. A total of 1061 E. coli strains of serogroups O55, O111, and O119 were initially characterised regarding their H types (serotypes) and the presence of EPEC DNA sequences, eae, EAF, and bfpA. In case of the serogroup O111 strains, 84.6% carried the typical EPEC markers, and the great majority of those (98.1%) were PPA-positive. In contrast, only 0.9% of the serogroups O55 and O119 strains carrying the typical EPEC markers (53.6% and 75.4%, respectively) were PPA-positive. We conclude that the PPA test is a useful method to detect typical EPEC strains only among strains of the O111 serogroup.

Virulence properties of Escherichia coli isolated from ostriches with respiratory disease.

Eight Escherichia coli isolates from ostriches with respiratory disease were investigated for the presence of genes encoding the following adhesins: type 1 pili (fim), pili associated with pyelonephritis (pap), S fimbriae (sfa), afimbrial adhesin (afaI), temperature regulated adhesin, curli (crl, csgA) and temperature-sensitive hemagglutinin (tsh). Genes for heat labile (LT) and heat stable (STa and STb) enterotoxins, Shiga toxins (stx1 and stx2), cytotoxic necrotizing factor 1 (cnf), alpha-haemolysin (hly) and aerobactin (aer) production were also investigated. Other characteristics investigated were the presence of hemagglutination activity, growth on an iron-deficient medium, aerobactin production, serum resistance, adherence to chicken tracheal cells, pathogenicity for day-old chicks, and serogroup. Serogrouping showed that four isolates belonged to serogroup O2, two to serogroup O78, one to serogroup O9, and one to serogroup O21. The virulence genes found were: fim in all eight isolates, csgA in seven, aer in six, and pap, crl and tsh in one isolate each. All isolates analyzed were positive for mannose-resistant hemagglutination, adhered in vitro to ciliated tracheal epithelium, grew on iron-deficient medium, and showed serum resistance. Pathogenicity tests on day-old chickens revealed one highly pathogenic isolate, three of low pathogenicity and four isolates with intermediate pathogenicity.

Molecular and cellular physiology of the dissociation of atrial natriuretic peptide from guanylyl cyclase a receptors.

Guanylyl cyclase subtype A (GCA) is the main receptor that mediates the effects of atrial natriuretic peptide (ANP) in the regulation of plasma volume and blood pressure. The dynamics of the dissociation of ANP from GCA were investigated in cultured Chinese hamster ovary (CHO) cells stably transfected with wild-type (WT) or mutant GCA receptors. The rate of dissociation of specifically bound (125)I-ANP-(1-28) from intact CHOGCAWT cells at 37 degrees C was extremely rapid (K(off) = 0.49 +/- 0.02 min(-1)), whereas in isolated membranes prepared from these cells, the dissociation at 37 degrees C was >10-fold slower (K(off) = 0.035 +/- 0.006 min(-1)). The dissociation of ANP from CHOGCAWT cells showed remarkable temperature dependence. Between 22 and 37 degrees C, K(off) increased approximately 8 times, whereas between 4 and 22 degrees C, it increased only 1.5 times. Total deletion of the cytoplasmic domain or of the catalytic guanylyl cyclase sequence within this domain abolished ANP-induced increases in cGMP, dramatically slowed receptor-ligand dissociation by at least 10-fold, and abolished the temperature dependence of the dissociation of ANP. Deletion of the kinase-like domain led to maximal constitutive activation of guanylyl cyclase, markedly decreased K(off) to 0.064 +/- 0.006 min(-1), and also abolished the temperature dependence of dissociation. Substitution of Ser(506) by Ala and particularly the double substitution of Gly(505) and Ser(506) by Ala within the kinase-like domain markedly reduced ANP-induced increases in cGMP, whereas K(off) decreased modestly (albeit significantly) to 0.36 +/- 0.03 and 0.24 +/- 0.02 min(-1), respectively. As a whole, the results demonstrate for the first time that temperature per se or ATP alone cannot account for rapid GCA receptor-ligand dissociation under physiological conditions and suggest that ligand dissociation is modulated in part by the interaction of still unidentified cytosolic factors with the cytoplasmic domain of GCA.

Interactions of Escherichia coli strains of non-EPEC serogroups that carry eae and lack the EAF and stx gene sequences with undifferentiated and differentiated intestinal human Caco-2 cells.

Escherichia coli strains of non-EPEC serotypes that carry eae and lack the EAF and the Shiga toxin (stx) gene sequences have been found in acute diarrhea. Both the cell association and the cell entry of these strains in human intestinal epithelial cells were studied as a function of cell differentiation and polarization. The eae+/EAF-/stx- non-EPEC E. coli strains invaded undifferentiated Caco-2 cells more efficiently than differentiated cells. In contrast, prototype EPEC strain E2348/69 did not show significative differences from invasion rates of undifferentiated and differentiated cells. The uptake of these strains was greatly enhanced by pretreatment of differentiated Caco-2 cells with EGTA. These results suggest that the eae+/EAF-/stx- non-EPEC E. coli invasion of intestinal cells may be dependent on receptors expressed on the surface of undifferentiated cells and the basolateral pole of differentiated cells.