RESUMO
AIMS: To compare the incidence of intra-operative haemorrhage from ovarian vessels during ovariectomy (OV) and ovariohysterectomy (OVH) in dogs and cats performed by inexperienced surgeons using surgeon's and constrictor knots to ligate the ovarian pedicles. METHODS: All client-owned female dogs (n = 51) and cats (n = 102) that presented for OV or OVH at two referral clinics in Belgium and France from January to June 2019 were included. Surgeries were performed by inexperienced surgeons under the supervision of diplomates or residents of the European College of Veterinary Surgeons. During routine and emergency OV or OVH one pedicle of each animal was ligated using a constrictor knot and the other with a surgeon's knot, the side assigned randomly. Time taken to perform each knot and the number of ligatures that resulted in intraoperative haemorrhage from the ovarian vessels were recorded. Body condition score (BCS) was recorded for 33 dogs and 22 cats. RESULTS: The median time taken to perform constrictor knots in dogs (81 seconds), was longer than for surgeon's knots (69 seconds; p = 0.005). In cats, the median time taken to perform constrictor knots (109 seconds) was also longer than for surgeon's knots (90.5 seconds; p = 0.02).The number of dogs that had intra-operative haemorrhages from pedicles ligated with constrictor knots (2/102; 3.9%) was less than those ligated with surgeon's knots (10/102; 19.6%; p = 0.027). The median BCS of dogs that experienced haemorrhage (n = 8; median 5/9, min 3/9, max 7/9) was higher (p = 0.019) than that of dogs that did not experience haemorrhage (n = 25; median 4/9, min 3/9, max 8/9).There was no evidence (p = 1.0) of a difference in the proportion of cats that experienced intra-operative haemorrhage from pedicles ligated with constrictor knots (3/44; 6.8%) and those ligated with surgeon's knots (2/44; 4.5%). Two-thirds of the haemorrhages with constrictor knots were caused by pedicle rupture during tightening. CONCLUSIONS: The rate of intraoperative haemorrhage from the ovarian pedicle was lower when a constrictor knot was used compared to a surgeon's knot in dogs but not in cats. While the constrictor knot was more time consuming to tie this is not likely to have a clinical impact. Use of this knot by inexperienced surgeons in dogs may help to reduce the risk of intraoperative haemorrhage during OVH/OV.
Assuntos
Doenças do Gato , Doenças do Cão , Cirurgiões , Animais , Gatos , Cães , Feminino , Humanos , Incidência , Ovariectomia/veterinária , Técnicas de Sutura/veterináriaRESUMO
The unfolded protein response (UPR) is a conserved and essential cellular pathway involved in protein quality control that is activated in response to several cellular stressors such as diseases states, ageing, infection and toxins. The cytosol, endoplasmic reticulum (ER) and mitochondria are continuously exposed to new proteins and in situations of aberrant protein folding; one of three lines of defence may be activated: (i) heat-shock response, (ii) mitochondrial UPR and (iii) ER UPR. These pathways lead to different signal transduction mechanisms that activate or upregulate transcription factors that, in turn, regulate genes that increase the cell's ability to correct the conformation of poorly folded proteins or, ultimately, lead to apoptosis. Despite the recent progress in understanding such biological processes, few studies have focused on the implications of the UPR in male infertility, highlighting the need for a first approach concerning the presence of these components in the male reproductive system. In testis, there is a high rate of protein synthesis, and the UPR mechanisms are well described. However, the presence of these mechanisms in spermatozoa, apparently transcriptionally inactive cells, is contentious, and it is unclear how sperm cells deal with stress. Here, we review current concepts and mechanisms of the UPR and highlight the relevance of these stress response pathways in male fertility, especially the presence and functional activation of those components in male germinal cells and spermatozoa.
Assuntos
Retículo Endoplasmático/metabolismo , Fertilidade/genética , Resposta ao Choque Térmico/genética , Infertilidade Masculina/genética , Espermatozoides/metabolismo , Resposta a Proteínas não Dobradas , Animais , Apoptose/genética , Citosol/metabolismo , Regulação da Expressão Gênica , Humanos , Infertilidade Masculina/metabolismo , Infertilidade Masculina/patologia , Masculino , Mitocôndrias/metabolismo , Dobramento de Proteína , Espermatozoides/citologia , Testículo/citologia , Testículo/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismoRESUMO
We investigate by molecular dynamics simulations the mobility of the water located at the DNA minor and major grooves. We employ the TIP3P water model, and our system is analyzed for a range of temperatures 190-300 K. For high temperatures, the water at the grooves shows an Arrhenius behavior similar to that observed in the bulk water. At lower temperatures, a departure from the bulk behavior is observed. This slowing down in the dynamics is compared with the dynamics of the hydrogen of the DNA at the grooves and with the autocorrelation functions of the water hydrogen bonds. Our results indicate that the hydrogen bonds of the water at the minor grooves are highly correlated, which suggests that this is the mechanism for the slow dynamics at this high confinement.
Assuntos
Temperatura Baixa , DNA/química , Modelos Moleculares , Água/química , Difusão , Ligação de Hidrogênio , Simulação de Dinâmica MolecularRESUMO
Children change their body size, shape, and gross motor coordination (GMC) as they grow. Further, GMC is expected to link to changes in children's body size, physical activity (PA), and physical fitness (PF). The objective was to model GMC changes in children followed longitudinally and to investigate associations between these changes and PA and PF levels. A total of 245 children (122 girls) were observed at 6 years of age and followed annually until 9 years. A sequence of allometric models was fitted, that is, 1. body mass, stature, and PA; 2. addition of four PF tests; 3. addition of four more PF tests. In Model 1, changes in GMC are nonlinear, and body mass (-0.60 ± 0.07, P < .001) and stature (2.91 ± 0.35, P < .001) parameter estimates were significant suggesting children with a more linear body size/shape showed higher GMC performances. Girls tend to outperform boys across time, and PA was not associated with GMC changes. Model 2 fitted the data better, and the PF tests (handgrip, standing long jump, 50-yard dash, and shuttle run) were significantly linked to GMC change. In Model 3, adding the remaining PF tests did not change the order of any factors importance. The greatest GMC changes were achieved by children whose body size/shape has an ectomorphic dominance across the years. Considering that leaner and physically fitter children tended to be more coordinated, physical education should also focus on PF development in components related to muscular strength, speed, agility, and aerobic capacity, along with nutritional education to reduce fat mass.
Assuntos
Desenvolvimento Infantil , Exercício Físico , Destreza Motora , Aptidão Física , Estatura , Tamanho Corporal , Criança , Feminino , Força da Mão , Humanos , Estudos Longitudinais , Masculino , Modelos Teóricos , SomatotiposAssuntos
Hamartoma , Dermatopatias , Humanos , Criança , Cirurgia de Mohs , Dermatopatias/cirurgia , Hamartoma/cirurgiaRESUMO
There is considerable evidence for an adaptive role of inversions, but how their genetic content evolves and affects the subsequent evolution of chromosomal polymorphism remains controversial. Here, we track how life-history traits, chromosomal arrangements and 22 microsatellites, within and outside inversions, change in three replicated populations of Drosophila subobscura for 30 generations of laboratory evolution since founding from the wild. The dynamics of fitness-related traits indicated adaptation to the new environment concomitant with directional evolution of chromosomal polymorphism. Evidence of selective changes in frequency of inversions was obtained for seven of 23 chromosomal arrangements, corroborating a role for inversions in adaptation. The evolution of linkage disequilibrium between some microsatellites and chromosomes suggested that adaptive changes in arrangements involved changes in their genetic content. Several microsatellite alleles increased in frequency more than expected by drift in targeted inversions in all replicate populations. In particular, there were signs of selection in the O3+4 arrangement favouring a combination of alleles in two loci linked to the inversion and changing along with it, although the lack of linkage disequilibrium between these loci precludes epistatic selection. Seven other alleles increased in frequency within inversions more than expected by drift, but were not in linkage disequilibrium with them. Possibly these alleles were hitchhiking along with alleles under selection that were not specific to those inversions. Overall, the selection detected on the genetic content of inversions, despite limited coverage of the genome, suggests that genetic changes within inversions play an important role in adaptation.
Assuntos
Inversão Cromossômica , Drosophila/genética , Desequilíbrio de Ligação , Adaptação Fisiológica , Alelos , Animais , Cromossomos , Polimorfismo GenéticoRESUMO
Four novel HLA-B alleles, B*42:20, B*51:151, B*57:64 and B*58:42 were identified in Brazilian individuals.
Assuntos
Antígenos HLA-B/genética , Teste de Histocompatibilidade , Alelos , Transplante de Medula Óssea , Brasil , Epitopos de Linfócito T/genética , Feminino , Genótipo , Humanos , Masculino , Conformação Molecular , Reação em Cadeia da Polimerase , Doadores de TecidosRESUMO
The aim of this study was to investigate the human leukocyte antigen (HLA) molecular variation across the Brazilian population in order to determine possible regional differences, which would be highly relevant to optimizing donor recruitment strategies in hematopoietic stem cell transplantation (HSCT) and understanding the population genetic background of this heterogeneous country. HLA data of 551 HSCT donors from five Brazilian regions were characterized by high-resolution DNA alleles at the HLA-A, -B, -C, -DRB1 and -DQB1 loci and compared with other populations in Brazil and worldwide populations. Allele and haplotype frequencies were estimated. The analysis was performed to assess Hardy-Weinberg equilibrium (HWE) and linkage disequilibrium (LD) among different loci in each recruitment center. Genetic variation was explored through genetic distance analyzed by using a new algorithm based on linear algebra, taking into account geographic regions of Brazil. The results indicated a heterogeneous genetic composition of the Brazilian population, such that HLA allele and haplotype frequencies exhibit different distributions among Brazilian regions, which has important implications for donor matching. In addition, a pronounced differentiation was observed by the absence of clustering of the regional populations in the reduced-dimension space. These data may be useful for increasing donor recruitment with more genetic representativeness in the Brazilian Volunteer Bone Marrow Donors Registry (REDOME).
Assuntos
Seleção do Doador , Genética Populacional , Antígenos HLA/genética , Células-Tronco Hematopoéticas/citologia , Doadores de Tecidos , Adolescente , Adulto , Alelos , Brasil , Frequência do Gene/genética , Loci Gênicos/genética , Variação Genética , Geografia , Haplótipos/genética , Humanos , Desequilíbrio de Ligação/genética , Pessoa de Meia-Idade , Filogenia , Adulto JovemRESUMO
Chromosomal inversions are present in a wide range of animals and plants, having an important role in adaptation and speciation. Although empirical evidence of their adaptive value is abundant, the role of different processes underlying evolution of chromosomal polymorphisms is not fully understood. History and selection are likely to shape inversion polymorphism variation to an extent yet largely unknown. Here, we perform a real-time evolution study addressing the role of historical constraints and selection in the evolution of these polymorphisms. We founded laboratory populations of Drosophila subobscura derived from three locations along the European cline and followed the evolutionary dynamics of inversion polymorphisms throughout the first 40 generations. At the beginning, populations were highly differentiated and remained so throughout generations. We report evidence of positive selection for some inversions, variable between foundations. Signs of negative selection were more frequent, in particular for most cold-climate standard inversions across the three foundations. We found that previously observed convergence at the phenotypic level in these populations was not associated with convergence in inversion frequencies. In conclusion, our study shows that selection has shaped the evolutionary dynamics of inversion frequencies, but doing so within the constraints imposed by previous history. Both history and selection are therefore fundamental to predict the evolutionary potential of different populations to respond to global environmental changes.
Assuntos
Adaptação Biológica/genética , Evolução Biológica , Inversão Cromossômica/genética , Drosophila/genética , Variação Genética , Modelos Genéticos , Seleção Genética , Animais , Mudança Climática , França , Países Baixos , PortugalRESUMO
AIM: Studies report that hormone replacement prevents osteoporosis, but there are doubts whether isoflavones are really efficient in this process. The aim of this study was to evaluate the effects of different doses of soy isoflavones on bone tissue of ovariectomized rats. METHODS: Forty female rats at the age of 6 months were ovariectomized and, after 3 months, the animals were divided into four groups: GI - Control (treated with drug vehicle); GII - treated with isoflavones (80 mg/kg per day); GIII - treated with isoflavones (200 mg/kg per day) and GIV - treated with isoflavones (350 mg/kg per day). Soy isoflavones were administered by gavage for 90 consecutive days. After treatment, the rats were euthanized and their distal femurs were removed for histological routine, histochemistry and biochemical study. Histological sections were stained with hematoxylin-eosin or subjected to picrosirius red and alcian blue methods. Shafts of femurs were submitted to biochemical assay and tibias were subjected to biophysical and biomechanical tests. RESULTS: In distal femurs, the trabecular bone volume was higher in the groups treated with isoflavones, being higher in GIV, while the cortical bone width and the presence of mature type I collagen fibers were higher in GII. At the trabecular bone region, the percentage of total glycosaminoglycans (GAGs) was higher in GII and the percentage of only sulfated GAGs was higher in GIII, while the higher content of chondroitin sulfate in shafts of femurs was seen in GIV. Biophysical and biomechanical tests in tibias did not differ among the groups. CONCLUSION: Our data indicate that soy isoflavones improve bone quality in femurs of rats by increasing histomorphometric parameters, the content of GAGs and mature type I collagen fibers. These positive effects are dose-dependent and it was different in cortical and trabecular bone.
Assuntos
Densidade Óssea/efeitos dos fármacos , Osso e Ossos/efeitos dos fármacos , Glycine max , Isoflavonas/farmacologia , Osteoporose , Ovariectomia/efeitos adversos , Extratos Vegetais/farmacologia , Animais , Osso e Ossos/metabolismo , Osso e Ossos/patologia , Colágeno Tipo I/metabolismo , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Feminino , Fêmur/metabolismo , Fêmur/patologia , Glicosaminoglicanos/metabolismo , Humanos , Osteoporose/tratamento farmacológico , Osteoporose/etiologia , Osteoporose/metabolismo , Ratos , Tíbia/metabolismo , Tíbia/patologia , Resultado do TratamentoRESUMO
OBJECTIVE: To evaluate the effects of soy isoflavone extract in the pro-oxidant/antioxidant balance in the uterus of ovariectomized rats. METHODS: Twenty 3-month-old adult female Wistar rats were divided into four equal groups: GI: sham-operated (estrous phase); GII: control ovariectomized rats; GIII: ovariectomized rats treated with genistein (50 µg/kg/day) by gavage; GIV: ovariectomized rats subcutaneously treated with estrogen (10 µg/kg/day). After 30 consecutive days of treatment, the rats were euthanized and the uterus removed. The distal thirds of the uterine horns were processed for histomorphometric analyses of endometrial and myometrial thicknesses and glandular area. Other regions of the uteri were kept in liquid nitrogen and subsequently processed for analysis of reactive species quantification (DCF), total antioxidant capacity (TAC) and lipid oxidation status (TBARS). Data were statistically analyzed by one-way ANOVA, complemented by the Tukey-Kramer test (p < 0.05). RESULTS: GII and GIII exhibited lower endometrial thickness, glandular area and myometrial thickness than GI and GIV, while a higher myometrial thickness was observed in GIV compared with the other groups. Moreover, the isoflavone-treated group showed lower DCF and TBARS compared to GII, and also an improvement of TAC compared to GI and GIV. Despite the significant decrease in TBARS, no significant difference in DCF nor a decrease in TAC were observed in GIV when compared to GII. CONCLUSION: Our data show that isoflavones improve antioxidant status and counteract oxidative stress, without promoting a trophic effect in the uterus of rats.
Assuntos
Genisteína/farmacologia , Glycine max , Ovariectomia/efeitos adversos , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Útero , Animais , Modelos Animais de Doenças , Vias de Administração de Medicamentos , Estrogênios/farmacologia , Feminino , Isoflavonas/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Fitoestrógenos/farmacologia , Progesterona/farmacologia , Ratos , Ratos Wistar , Resultado do Tratamento , Útero/efeitos dos fármacos , Útero/metabolismo , Útero/patologiaRESUMO
Four novel human leucocyte antigen (HLA) class II alleles were identified by sequencing-based typing (SBT) and analysis of the closest-matching alleles from volunteer subjects from the Brazilian Bone Marrow Donor Register (REDOME, Brazil). The new HLA alleles discovered include DRB1*04:11:03, DRB1*10:05, DRB1*15:94 and DRB1*16:22. Three of the novel alleles had single-nucleotide substitution polymorphisms when compared to their most homologous allele. Of these, one harboured a single-nucleotide polymorphism (SNP) identified as a silent substitution.
Assuntos
Cadeias HLA-DRB1/genética , Alelos , Substituição de Aminoácidos , Sequência de Bases , Brasil , Éxons , Feminino , Humanos , Masculino , Dados de Sequência Molecular , Polimorfismo de Nucleotídeo Único , Doadores de TecidosRESUMO
Five novel HLA-B alleles were identified by HLA-SBT typing in seven unrelated Brazilian individuals. The new alleles discovered include HLA-B*07:184, B*41:27, B*42:19, B*50:32 and B*57:63 and were officially named by the World Health Organization (WHO) Nomenclature Committee. All new HLA-B alleles had nonsynonymous nucleotide substitution polymorphisms when compared to their most closely related HLA-B allele.
Assuntos
Alelos , Éxons , Antígenos HLA-B/genética , Polimorfismo Genético , Adolescente , Adulto , Sequência de Bases , Transplante de Medula Óssea , Brasil , Feminino , Expressão Gênica , Antígenos HLA-B/imunologia , Teste de Histocompatibilidade , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Moleculares , Dados de Sequência Molecular , Doadores de TecidosRESUMO
Levels of calcium in the haemolymph and reserves in the shell of Biomphalaria glabrata experimentally infected by Angiostrongylus cantonensis were determined for the first time. At the same time, histochemical analyses of the digestive gland of infected and uninfected snails were performed to better understand the possible changes in metabolism of calcium in these organisms. After 1, 2 and 3 weeks of infection, the snails were dissected for collection of haemolymph and separation of tissues. The highest calcium concentrations in the haemolymph were found 2 weeks after infection, with a 39.61% increase in relation to the respective control group. However, there was a significant reduction in the concentration of this ion in the haemolymph of infected snails after 1 week of infection in relation to the uninfected specimens. In parallel, intense hypocalcification was shown in the shell of infected snails 1 and 2 weeks after infection, differing significantly in relation to the respective control groups. Morphological changes in the digestive gland of infected snails were also observed, confirming the role of this ion as an important element in the parasite encapsulation process.
Assuntos
Angiostrongylus cantonensis/crescimento & desenvolvimento , Biomphalaria/metabolismo , Biomphalaria/parasitologia , Cálcio/metabolismo , Exoesqueleto/química , Animais , Sistema Digestório/parasitologia , Sistema Digestório/patologia , Hemolinfa/química , HistocitoquímicaRESUMO
OBJECTIVES: An integrative taxonomic description of Aponurus laguncula (Lecithasteridae), a digenean parasitic species of Chaetodipterus faber (Acanthuriformes) from Brazilian Southeast, is provided. Morphological techniques, as whole mounted slides, histology and scanning electron microscopy, and molecular analyses supported that integrative description. METHODS: Fifteen digenean specimens were stained in hydrochloric carmine and mounted on permanent slides. Two specimens were stained in hematoxylin and eosin following histological routine processing. Four parasites were dehydrated through a graded ethanol series, critical point dried with carbon dioxide and coated with gold to scanning electron microscopy analysis. Sequence of the large ribosomal subunit (28S rDNA) gene was generated and used to construct a phylogeny based on maximum likelihood and Bayesian inference analyses. RESULTS: Morphological description and morphometric data obtained in present study were in accordance with previous studies of the species. Use of another morphological techniques, as scanning electron microscopy and histology, corroborated the observed features of whole mounted slides. Also, they provided a better observation of previous reported characteristics and new features reporting, such as an elongated hermaphroditic duct, a smooth tegument and cells that compose the prostatic gland. The molecular sequence obtained in the present study formed a robust clade with available sequences of species of Aponurus. CONCLUSIONS: The integrative taxonomic approach successfully combined morphological observations, including both previously reported features and new descriptions from histological and electron microscopy analyses, with molecular data to identify these specimens as A. laguncula. Moreover, the detailed characterization of structures, such as the gonads in A. laguncula, that would be challenging to analyze using a single technique, was possible. Further molecular studies with less conserved genetic markers should be conducted to understand phylogenetic relationships between Aponurus species.
RESUMO
OBJECTIVES: The present work aims to expand the knowledge of the digenean species Prosogonotrema bilabiatum (Sclerodistomidae), a parasite of Chaetodipterus faber (Acanthuriformes) from Brazil, with an integrative taxonomic approach, using light microscopy, scanning electron microscopy, histology, and molecular biology. METHODS: Forty-one digenean specimens were stained with hydrochloric carmine for morphological studies. Eleven parasites were dehydrated through a graded ethanol series, critical point dried with carbon dioxide, and coated with gold for scanning electron microscopy analysis. Four specimens were processed following histological routine and stained with hematoxylin and eosin and Gomori trichrome. DNA extracted was amplified using 28S partial primer D1-D3. Maximum likelihood and Bayesian inference were performed for phylogenetic analysis. RESULTS: Morphometric and morphological data of the specimens studied ranged in accordance as observed in previous descriptions of the species. Observations from scanning electron microscopy and histology corroborated with those observed in stained whole mounts. Molecular analysis showed that specimens of P. bilabiatum from Brazil clustered with another two sequences of this species from different hosts and localities, with a high node support value. CONCLUSIONS: The integrative taxonomic approach allowed to record and describe new characteristics of P. bilabiatum related to the tegument, the structure and the arrangement of its tissues. The use of molecular markers confirmed that specimens identified as P. bilabiatum from different hosts and localities are all conspecific. Further studies, mainly molecular with less conserved genetic markers, should be carried out to better understand the phylogenetic relationships of Prosogonotrema with Hemiuroidea.
Assuntos
Doenças dos Peixes , Microscopia Eletrônica de Varredura , Filogenia , Trematódeos , Infecções por Trematódeos , Animais , Brasil/epidemiologia , Doenças dos Peixes/parasitologia , Trematódeos/classificação , Trematódeos/genética , Trematódeos/ultraestrutura , Trematódeos/anatomia & histologia , Trematódeos/isolamento & purificação , Microscopia Eletrônica de Varredura/veterinária , Infecções por Trematódeos/parasitologia , Infecções por Trematódeos/veterinária , Infecções por Trematódeos/epidemiologia , Peixes/parasitologia , DNA de Helmintos/genética , RNA Ribossômico 28S/genéticaRESUMO
Given the recognized major problem of microbial drug resistance for human health, new metal-based drugs have been currently explored for their antimicrobial properties, including gallium-based compounds as potential metallophores that could perturb Fe's interactions with proteins. Herein we have designed and synthesized two bis-kojate ligands (named L4 and L6) and studied their Ga(III) complexes for their physico-chemical and biological properties. In particular a detailed study of their complexation properties in aqueous solution, showed equilibrium models with formation of quite stable dinuclear 2:3 metal:ligand complexes, though with different stability. Solid state complexes were also prepared and characterized and complementary DFT studies indicated that [Ga2(L4)3] complex, with higher stability, seems to adopt a three-ligand bridging conformation, while that for L6 adopt a one ligand bridging conformation. Preliminary investigation of the antibacterial activity of these gallium complexes showed antipseudomonal activity, which appeared higher for the complex with L4, a feature of potential interest for the scientific community.
Assuntos
Antibacterianos , Complexos de Coordenação , Gálio , Testes de Sensibilidade Microbiana , Gálio/química , Gálio/farmacologia , Antibacterianos/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Complexos de Coordenação/farmacologia , Complexos de Coordenação/síntese química , Complexos de Coordenação/química , LigantesRESUMO
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.