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1.
Neurosci Biobehav Rev ; 145: 105018, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36572200

RESUMO

Sex steroid hormones play an important role in fetal development, brain functioning and neuronal protection. Growing evidence highlights the positive effects of these hormones against brain damage induced by neonatal hypoxia-ischemia (HI). This systematic review with meta-analysis aims to verify the efficacy of sex steroid hormones in preventing HI-induced brain damage in rodent models. The protocol was registered at PROSPERO and a total of 22 articles were included. Moderate to large effects were observed in HI animals treated with sex steroid hormones in reducing cerebral infarction size and cell death, increasing neuronal survival, and mitigating neuroinflammatory responses and astrocyte reactivity. A small effect was evidenced for cognitive function, but no significant effect for motor function; moreover, a high degree of heterogeneity was observed. In summary, data suggest that sex steroid hormones, such as progesterone and 17ß estradiol, improve morphological and cellular outcomes following neonatal HI. Further research is paramount to examine neurological function during HI recovery and standardization of methodological aspects is imperative to reduce the risk of spurious findings.


Assuntos
Hormônios Esteroides Gonadais , Hipóxia-Isquemia Encefálica , Animais , Animais Recém-Nascidos , Encéfalo , Estradiol , Hipóxia-Isquemia Encefálica/tratamento farmacológico , Hipóxia-Isquemia Encefálica/metabolismo , Isquemia , Progesterona/farmacologia , Progesterona/uso terapêutico
2.
Nat Commun ; 13(1): 447, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35105878

RESUMO

Trojan asteroids are small bodies orbiting around the L4 or L5 Lagrangian points of a Sun-planet system. Due to their peculiar orbits, they provide key constraints to the Solar System evolution models. Despite numerous dedicated observational efforts in the last decade, asteroid 2010 TK7 has been the only known Earth Trojan thus far. Here we confirm that the recently discovered 2020 XL5 is the second transient Earth Trojan known. To study its orbit, we used archival data from 2012 to 2019 and observed the object in 2021 from three ground-based observatories. Our study of its orbital stability shows that 2020 XL5 will remain in L4 for at least 4 000 years. With a photometric analysis we estimate its absolute magnitude to be [Formula: see text], and color indices suggestive of a C-complex taxonomy. Assuming an albedo of 0.06 ± 0.03, we obtain a diameter of 1.18 ± 0.08 km, larger than the first known Earth Trojan asteroid.

3.
Brain Res ; 1733: 146722, 2020 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-32045594

RESUMO

Neonatal hypoxia-ischemia (HI) is one of the main causes of neurological damage in newborns. Pregnancy swimming (PS) alters brain maturation and has neuroprotective effects following HI; however, variables such as timing play a decisive role in its effects. Prior to mating, we tested if adaptation of female rats to a tank filled with water at 32 °C for 7 days before mating, modulates PS benefits. After mating, rats swam 20 min/day or remained in standard cages. Seven-day-old pups were subjected to HI (right common carotid artery occlusion followed by FiO2 8% for 60 min). Animals were divided into 8 experimental groups, adaptation, swimming and injury. Astrocytic reactivity, apoptosis-related proteins, neurotrophins and cell survival markers expression were assessed in the hippocampus 24 h after HI. From PND45, animals performed behavioral tests followed by histological assessment. Three-way ANOVA showed a significant increase in astrogliosis only in non-adapted HI animals. Swimming decreased apoptotic cell death despite adaptation period in both exercised groups. Cylinder evidenced HI impairments; no effect of swimming or adaptation period were observed. In the open field, only HI animals whose mothers had been adapted had increased locomotion; moreover, swimming reversed HI damage. Hemisphere and hippocampus were preserved only in the HI group whose mothers swam before mating, suggesting a preconditioning effect mediated by the adaptation. In summary, adaptation period plays a major role in the mechanisms involving neuroprotection afforded by PS and needs to be further explored in future studies involving damage to the neonatal brain.


Assuntos
Adaptação Fisiológica , Hipocampo/metabolismo , Hipóxia-Isquemia Encefálica/metabolismo , Neuroproteção , Natação , Animais , Animais Recém-Nascidos , Comportamento Animal , Feminino , Hipóxia-Isquemia Encefálica/prevenção & controle , Gravidez , Ratos Wistar
4.
Genome Announc ; 6(13)2018 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-29599151

RESUMO

We report here the draft genome sequences of Klebsiella pneumoniae strains Kp1803 and Kp3380 isolated during a large outbreak at A Coruña Hospital in Spain. The final genome assemblies for Kp1803 and Kp3380 comprise approximately 6.6 and 6.1 Mb, respectively, and both strains have G+C contents of 57.2%.

5.
J Pediatr Urol ; 13(4): 387.e1-387.e6, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28434632

RESUMO

INTRODUCTION: Lower urinary tract dysfunction (LUTD) involves faults in the filling and emptying phases of bladder function in toilet-trained children with no previous infection or any other obvious pathology. Lower urinary tract dysfunction is associated with conditions such as vesicoureteral reflux, recurrent urinary infection, behavioral alterations and decreased quality of life. The literature suggests an association between LUTD and obesity; however, the association between each individual symptom and obesity has yet to be evaluated. OBJECTIVE: To evaluate the association between excess weight and LUTD in children and adolescents in a community-based sample. STUDY DESIGN: This cross-sectional study included 423 children and adolescents aged 5-17 years, and randomly selected in public places and schools between May and July 2015. The participants and their mothers completed the Dysfunctional Voiding Scoring System (DVSS) questionnaire, except for the questions on constipation and with the addition of a question on enuresis. They also completed the Rome III questionnaire, in which two positive responses defined the presence of constipation. Participants were classified as being of normal weight, overweight or obese, which was based on the BMI-for-age indicator. RESULTS: Mean age was 9.7 years (SD 2.9), with girls comprising 50.6% of the sample and adolescents 52.5%. The prevalence of LUTD was 7.1%, with 13.5% of participants being overweight and 12.1% obese (Figure). Constipation was present in 5.9% of participants and enuresis in 10.8%. In the multivariate analysis, three factors were independently and significantly associated with a positive DVSS: age <10 years (ß = 0.76; 95% CI: 0.34-1.18), constipation (ß = 1.79; 95% CI: 0.88-2.70) and obesity (ß = 0.89; 95% CI: 0.25-1.52). DISCUSSION: Only bladder filling symptoms were associated with obesity. This may be explained by the fact that both obese individuals and those with emptying symptoms were shown to have activation alterations in the same brain regions. One limitation of this study was the use of questionnaires alone to diagnose LUTD and constipation. CONCLUSION: Only the bladder-emptying symptoms of LUTD appear to be associated with obesity. This hypothesis may serve as a basis for future studies.


Assuntos
Sintomas do Trato Urinário Inferior/epidemiologia , Obesidade/complicações , Adolescente , Criança , Constipação Intestinal/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Prevalência , Qualidade de Vida , Fatores de Risco , Inquéritos e Questionários
6.
Artigo em Inglês | MEDLINE | ID: mdl-28254380

RESUMO

We determined the activity of glyceroneogenesis from [2-14C]-pyruvate, the phosphoenolpyruvate carboxykinase activity, [2-14C]-pyruvate oxidation and total lipid levels in the hepatopancreas of the crab Neohelice granulata fed with a carbohydrate-rich (HC) diet or a high-protein (HP) diet and then subjected to 5weeks of starvation, in summer and winter, to determine whether the seasonal adjustments of lipid metabolism to food scarcity are modulated by the composition of the diet previously given to the crabs. The results demonstrated that glyceroneogenesis is an active pathway in N. granulata hepatopancreas, and is regulated by seasonal variations, diet composition and starvation. This study showed that in summer the increase in the hepatopancreas glyceroneogenesis activity is among the strategies used by N. granulata fed an HP diet, to maintain the triglyceride/fatty acid cycle during starvation, a normal condition in the biological cycle of this crab. However, the administration of an HC diet reduced the glyceroneogenesis capacity in response to starvation in summer. In winter, the decrease in the glyceroneogenesis capacity in both fed (HP and HC diets) and starved crabs seems to be a strategy to reduce energy consumption and/or requirement. In contrast to the summer results, the incorporation of [2-14C]-pyruvate into 14CO2 was markedly higher in both diet (HC and HP) groups and in starved crabs during the winter. Four decades after the first study describing the glyceroneogenesis pathway in rat white adipose tissue, this pathway is evidenced for the first time in a crustacean.


Assuntos
Braquiúros/metabolismo , Dieta , Gluconeogênese/fisiologia , Glucose/metabolismo , Glicerol/metabolismo , Hepatopâncreas/metabolismo , Inanição , Animais , Carboidratos da Dieta/metabolismo , Proteínas Alimentares/metabolismo , Ácidos Graxos/metabolismo , Estações do Ano
7.
Braz J Med Biol Res ; 50(2): e5801, 2017 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-28225868

RESUMO

We determined the effect of N-acetylcysteine (NAC) on the expression of the phosphorylated p38 (p-p38) protein and superoxide anion generation (SAG), two important players in the processing of neuropathic pain, in the lumbosacral spinal cord of rats with chronic constriction injury (CCI)-induced neuropathic pain. The sciatic functional index (SFI) was also measured to assess the functional recovery post-nerve lesion. Thirty-six male Wistar rats were divided equally into the following groups: Naive (rats did not undergo surgical manipulation); Sham (rats in which all surgical procedures involved in CCI were used except the ligature), and CCI (rats in which four ligatures were tied loosely around the right common sciatic nerve), which received 2, 4, or 8 intraperitoneal injections of NAC (150 mg·kg-1·day-1) or saline beginning 4 h after CCI. Rats were sacrificed 1, 3, and 7 days after CCI. The SFI was measured on these days and the lumbosacral spinal cord was used for analysis of p-p38 expression and SAG. CCI induced a decrease in SFI as well as an increase in p-p38 expression and SAG in the spinal cord. The SFI showed a partial recovery at day 7 in saline-treated CCI rats, but recovery was improved in NAC-treated CCI rats. NAC induced a downregulation in p-p38 expression at all time-points evaluated, but did not reverse the increased SAG induced by CCI. Since p-p38 is a mediator in neuropathic pain and/or nerve regeneration, modulation of this protein may play a role in NAC-induced effects in CCI rats.


Assuntos
Acetilcisteína/uso terapêutico , Neuralgia/tratamento farmacológico , Medula Espinal/efeitos dos fármacos , Superóxidos/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/efeitos dos fármacos , Animais , Western Blotting , Constrição Patológica , Modelos Animais de Doenças , Regulação para Baixo/efeitos dos fármacos , Masculino , Neuralgia/etiologia , Limiar da Dor , Fosforilação/efeitos dos fármacos , Ratos , Ratos Wistar , Medula Espinal/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
8.
Virulence ; 8(6): 959-974, 2017 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-27858524

RESUMO

Acinetobacter baumannii is a hospital-acquired pathogen that shows an extraordinary capacity to stay in the hospital environment. Adherence of the bacteria to eukaryotic cells or to abiotic surfaces is the first step for establishing an infection. The A. baumannii strain AbH12O-A2 showed an exceptional ability to adhere to A549 epithelial cells. The AbFhaB/FhaC 2-partner secretion (TPS) system involved in adhesion was discovered after the screening of the recently determined A. baumannii AbH12O-A2 strain genome (CP009534.1). The AbFhaB is a large exoprotein which transport to the bacterial surface is mediated by the AbFhaC protein. In the present study, the role of this TPS system in the AbH12O-A2 adherence phenotype was investigated. The functional inactivation of this 2-partner secretion system was addressed by analyzing the outer membrane vesicles (OMV) proteomic profile from the wild-type strain and its derivative mutant AbH12O-A2ΔfhaC demonstrating that AbFhaB is no longer detected in the absence of AbFhaC. Scanning electron microscopy (SEM) and adhesion experiments demonstrated that inactivation of the AbFhaB/FhaC system significantly decreases bacterial attachment to A549 alveolar epithelial cells. Moreover, it has been demonstrated that this 2-partner secretion system is involved in fibronectin-mediated adherence of the A. baumannii AbH12O-A2 isolate. Finally, we report that the AbFhaB/FhaC system is involved in virulence when tested using invertebrate and vertebrate hosts. These data suggest the potential role that this AbFhaB/FhaC secretion system could play in the pathobiology of A. baumannii.


Assuntos
Acinetobacter baumannii/patogenicidade , Adesinas Bacterianas/metabolismo , Aderência Bacteriana , Sistemas de Secreção Tipo V/metabolismo , Células A549 , Infecções por Acinetobacter/microbiologia , Acinetobacter baumannii/metabolismo , Células Epiteliais/microbiologia , Humanos , Microscopia Eletrônica de Varredura , Proteômica , Virulência
9.
Genome Announc ; 4(5)2016 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-27609928

RESUMO

Increased expression of chromosomal genes for resistance-nodulation-cell division-type efflux systems plays a major role in the multidrug resistance of Acinetobacter baumannii Little is known about the genetic characteristics of clinical strains of Acinetobacter baumannii lacking the AdeABC pump. In this study, we sequenced the genome of clinical strain Ab421 GEIH-2010 (belonging to clone ST79/PFGE-HUI-1 from the GEIH-REIPI Ab. 2010 project) which lacks this efflux pump.

10.
Genet Mol Res ; 15(3)2016 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-27525841

RESUMO

Some cases of recurrent first trimester miscarriage have a thrombotic etiology. The aim of this study was to investigate the prevalence of the most common thrombophilic mutations - factor V (FV) Leiden G1691A (FVL), prothrombin (FII) G20210A, and methylenetetrahydrofolate reductase (MTHFR) C677T - in women with recurrent miscarriages. In this case-control study, we included 137 women with two or more consecutive first-trimester miscarriages (£12 weeks of gestation) and 100 healthy women with no history of pregnancy loss, and with at least one living child. DNA was extracted from the patient samples, and the relevant genes (FVL, FII, and MTHFR) were amplified by PCR, followed by restriction fragment length polymorphism, to assess the polymorphisms in these genes. The allelic frequencies of polymorphisms were not significantly different between the case and control groups. Polymorphisms in the MTHFR, FVL, and FII genes were not associated with recurrent miscarriage during the first trimester of pregnancy in Brazilian women (P = 0.479; P = 0.491 and P = 0.107, respectively). However, the etiologic identification of genetic factors is important for genetic counseling.


Assuntos
Aborto Habitual/genética , Fator V/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Polimorfismo de Fragmento de Restrição , Protrombina/genética , Adulto , Estudos de Casos e Controles , Feminino , Frequência do Gene , Humanos , Gravidez
11.
Data Brief ; 7: 1483-5, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27182544

RESUMO

Data of optical performance, thermal stability and ageing are given for solar selective coatings (SSC) based on a novel MoSi2-Si3N4 absorbing composite. SSC have been prepared as multilayer stacks formed by silver as metallic infrared reflector, a double layer composite and an antireflective layer (doi: 10.1016/j.solmat.2016.04.001 [1]). Spectroscopic reflectance data corresponding to the optical performance of samples after moderate vacuum annealing at temperatures up to 600 °C and after ageing test of more than 200 h with several heating-cooling cycles are shown here.

12.
Genome Announc ; 2(6)2014 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-25395646

RESUMO

We report the complete genome sequence of Acinetobacter baumannii strain AbH12O-A2, isolated during a large outbreak in Spain. The genome has 3,875,775 bp and 3,526 coding sequences, with 39.4% G+C content. The availability of this genome will facilitate the study of the pathogenicity of the Acinetobacter species.

13.
Mol Biol Rep ; 41(3): 1871-7, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24435975

RESUMO

The p53 protein is known for performing essential functions in the maintenance of genomic stability in somatic cells and prevention of tumor formation. Studies of the p53 signaling pathway have suggested associations between some polymorphisms and infertility, post-in vitro fertilization implantation failure and recurrent abortions. The TP53 Pro72Arg polymorphism has been implicated as a risk factor for recurrent pregnancy loss (RPL); however, the association is controversial. In this study, our objective was to evaluate selected polymorphisms in genes of the p53 signalling pathway [TP53 c.215G>C (Pro72Arg), MDM2 c.14+309T>G (SNP309) and LIF c.1414T>G in the region 3' UTR] and determine their effect as risk factors for RPL. In a case-control study, we investigated 120 women with two or more pregnancy losses and 143 fertile control women reporting at least two live births and no history of pregnancy loss. When analyzed separately, the allele and genotype distributions of the polymorphisms in the two groups were not different. However, in a multivariate analysis adjusted for alcohol consumption, smoking, ethnicity, and number of pregnancies, the interaction between the genotypes TP53 Arg/Arg (rs1042522) and MDM2 TT (rs2279744) showed to be associated to RPL, increasing the risk for this condition (OR = 2.58, 95% CI: 1.31-5.07, p = 0.006). In conclusion, our study indicates that the combination of TP53 Arg/Arg (rs1042522) and MDM2 TT (rs2279744) genotypes may be a risk factor for RPL.


Assuntos
Aborto Habitual/genética , Predisposição Genética para Doença , Proteínas Proto-Oncogênicas c-mdm2/genética , Proteína Supressora de Tumor p53/genética , Aborto Habitual/patologia , Alelos , Estudos de Casos e Controles , Etnicidade , Feminino , Estudos de Associação Genética , Humanos , Polimorfismo de Nucleotídeo Único , Gravidez , Fatores de Risco , Transdução de Sinais/genética
14.
Genet Mol Res ; 12(1): 562-8, 2013 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-23512673

RESUMO

The endothelial nitric oxide synthase (eNOS) plays an important homeostatic role in the cardiovascular system (CVS) by maintaining appropriate blood pressure through production of nitric oxide. The 894TT genotype of 894G>T (Glu298Asp, rs1799983), a polymorphic variant of eNOS, has been associated with several vascular diseases. On the basis of this strong relationship, we monitored daily 585 critically ill adult patients according to their degree of CVS dysfunction and investigated their disease progression by the 894G>T genotype. To obtain information of the general population, we obtained the 894G>T genotypic and allelic frequencies in a random group of 149 healthy subjects. The patients were genotyped for the eNOS 894G>T polymorphism and daily evaluated according to their degree of CVS dysfunction through the Cardiovascular Sequential Organ Failure Assessment (SOFA) score. The mean value of the global CVS dysfunction score was significantly higher in 894TT patients (1.35 ± 0.57) than in non-894TT patients (1.23 ± 0.37; P = 0.035). This score remained significantly higher in 894TT patients, even in different patient clusters (all patients, septic, and non-septic patients) during the 1st week at the intensive care unit (1.86 ± 0.8 versus 1.63 ± 0.62, P = 0.005; 2.32 ± 0.10 versus 2.06 ± 0.08, P = 0.009; 0.84 ± 0.09 versus 0.64 ± 0.08, P = 0.027; respectively). This result shows that the mean values of the cardiovascular SOFA score were higher in 894TT patients in all subgroups. The present study provides evidence that the 894TT eNOS genotype is associated with a higher degree of CVS dysfunction in critically ill patients.


Assuntos
Sistema Cardiovascular/metabolismo , Unidades de Terapia Intensiva/estatística & dados numéricos , Óxido Nítrico Sintase Tipo III/genética , Polimorfismo de Nucleotídeo Único , Adulto , Idoso , Sistema Cardiovascular/patologia , Sistema Cardiovascular/fisiopatologia , Estado Terminal , Feminino , Frequência do Gene , Predisposição Genética para Doença/genética , Humanos , Desequilíbrio de Ligação , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença
15.
Ultramicroscopy ; 101(2-4): 129-38, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15450658

RESUMO

In the process of three-dimensional reconstruction of single particle biological macromolecules several hundreds, or thousands, of projection images are taken from tens or hundreds of independently digitized micrographs. These different micrographs show differences in the background grey level and particle contrast and, therefore, have to be normalized by scaling their pixel values before entering the reconstruction process. In this work several normalization procedures are studied using a statistical comparison framework. We finally show that the use of the different normalization methods affects the reconstruction quality, providing guidance on the choice of normalization procedures.


Assuntos
Diagnóstico por Imagem/métodos , Processamento de Imagem Assistida por Computador/métodos , Microscopia Eletrônica , Algoritmos , Modelos Teóricos , Estrutura Molecular
16.
Mediators Inflamm ; 13(5-6): 327-33, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15770048

RESUMO

BACKGROUND: Aging is associated with several alterations in the phenotype, repertoire and activation status of lymphocytes as well as in the cytokine profile produced by these cells. As a lifelong condition, chronic parasitic diseases such as human schistosomiasis overlaps with the aging process and no systematic study has yet addressed the changes in immune response during infection with Schistosoma mansoni in older individuals. AIM: Herein we study the influence of immunological alterations brought about by senescence in the course of schistosomiasis. MATERIALS AND METHODS: Individuals 10-95 years of age, from both sexes, from an endemic area for S. mansoni infection were matched by intensity of infection as measured by egg counts. We analyzed, as a parameter, cytokine expression by lymphocytes and natural killer cells after in vitro stimulation with soluble egg antigen and soluble worm antigen using flow cytometry. RESULTS: We demonstrated that the frequency of CD16+ interferon-gamma (IFN-gamma)+ natural killer cells in negative individuals over the age of 70 years is significantly higher than in positive individuals after in vitro stimulation with S. mansoni antigen extracts. The frequency of these cells is increased in all individuals over the age of 50 years and only declines in positive individuals after 70 years of age. Analysis of either CD4? or CD8? cells after antigen stimulation show no significant increase in frequency of IFN-gamma in negative or in positive individuals of this age group, suggesting that the effect on CD16+ cells is not T-cell dependent. CONCLUSION: Since production of IFN-gamma has been related to resistance to schistosome infection, our data suggest that age-associated changes in CD16+ cells may play a role in controlling infection intensity in the elderly in S. mansoni endemic areas of Brazil.


Assuntos
Envelhecimento/imunologia , Interferon gama/biossíntese , Células Matadoras Naturais/imunologia , Esquistossomose mansoni/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Brasil , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Estudos de Casos e Controles , Criança , Estudos Transversais , Feminino , Humanos , Técnicas In Vitro , Masculino , Pessoa de Meia-Idade , Contagem de Ovos de Parasitas , Schistosoma mansoni/imunologia , Schistosoma mansoni/isolamento & purificação , Esquistossomose mansoni/parasitologia
17.
Am J Trop Med Hyg ; 67(4): 336-43, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12452486

RESUMO

This study quantifies the influence of shared household and kinship on egg counts during Schistosoma mansoni infection in a sample from rural Brazil. Detailed genealogic information allowed assignment of 597 individuals to 6 multihousehold pedigrees residing in 145 households. A variance component method was used to partition egg counts into shared household, additive genetic, and individual-specific environmental effects. Host additive genetic effects consistently accounted for a large proportion of the variation in egg counts: 43% in an unadjusted model and 40% in model adjusted for covariates. In a model that examined the confounding of shared household with kinship, additive genetic effects still accounted for 27% of the variation in egg counts and shared household only 12%. The consistently important role for host additive genetic factors on the variation in egg counts points to new ways of modeling and understanding the mechanisms that contribute to trait variation during infection with S. mansoni.


Assuntos
Fezes/parasitologia , Predisposição Genética para Doença , Contagem de Ovos de Parasitas , População Rural , Schistosoma mansoni/isolamento & purificação , Esquistossomose/parasitologia , Animais , Brasil/epidemiologia , Funções Verossimilhança , Esquistossomose/epidemiologia , Esquistossomose/fisiopatologia
18.
Quintessence Int ; 32(6): 463-8, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11491626

RESUMO

OBJECTIVE: The objective of the present study was to clinically evaluate the hybrid materials Vitremer and Dyract when used as pit and fissure sealants. METHOD AND MATERIALS: The materials were applied in pairs on the mandibular permanent first molars of 100 children, 7 to 8 years old. RESULTS: After 12 months of sealing, the clinical evaluation presented rates of 95.9% and 85.7% of complete retention for Dyract and Vitremer, respectively, indicating a statistically significant difference. The hybrid materials presented a statistically significant protective effect against caries compared with the control group at 6 and 12 months. CONCLUSION: The hybrid materials were able to control occlusal caries.


Assuntos
Colagem Dentária , Cárie Dentária/prevenção & controle , Cimentos de Ionômeros de Vidro/uso terapêutico , Selantes de Fossas e Fissuras/uso terapêutico , Cimentos de Resina/uso terapêutico , Condicionamento Ácido do Dente , Estudos de Casos e Controles , Criança , Compômeros/uso terapêutico , Resinas Compostas/uso terapêutico , Amálgama Dentário , Restauração Dentária Permanente , Seguimentos , Humanos , Metacrilatos/uso terapêutico , Dente Molar , Razão de Chances , Silicatos/uso terapêutico , Propriedades de Superfície
19.
J Hered ; 92(3): 248-53, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11447240

RESUMO

Mitochondrial markers are often hailed as the preferred DNA elements for analyses of population subdivision. To this end we have employed a mitochondrial repeat element to examine the population structure in Schistosoma mansoni (human blood flukes). Schistosome isolates were collected from each of 21 different patients representing seven different areas of a Brazilian village. These parasite isolates demonstrate substantial genetic polymorphism, with an average of 10 genotypes infecting each patient, which is more readily detected because of high levels of heteroplasmy (i.e., 72.5% of the individual worms exhibit multiple versions of this repeat region with different numbers of repeats). Due to the high number of common haplotypes in the population, this repeat element from S. mansoni has a large proportion (47%) of its genetic variation described by differences among mitochondrial genomes within individual worms. However, when only rare haplotypes are considered, population structure can be detected. It seems that heteroplasmy in the schistosome population of Melquiades is both the source of plentiful genetic variation and a confounding factor in the analysis of that variation. Thus the schistosome population in Melquiades may actually be more strongly subdivided than we are able to detect using this mitochondrial marker.


Assuntos
DNA Mitocondrial/genética , Variação Genética , Schistosoma mansoni/genética , Sequências de Repetição em Tandem/genética , Animais , DNA de Protozoário/análise , Fezes/parasitologia , Feminino , Genética Populacional , Genótipo , Haplótipos , Humanos , Masculino , Camundongos , Repetições de Microssatélites , Polimorfismo Genético , Schistosoma mansoni/isolamento & purificação , Caramujos/parasitologia
20.
Trop Med Int Health ; 6(2): 126-35, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11251909

RESUMO

The study of water contact patterns in rural Brazil presents unique challenges due to widely dispersed settlement patterns, the ubiquity of water contact sites, and the privatization of water resources. This study addresses these challenges by comparing the two most widely used methods of assessing water contact behaviour: direct observation and survey. The results of a 7-day direct observation of water contact were compared with water contact surveys administered 1 week after and then 1 year after the direct observation study. The direct observation study recorded a water contact rate higher than reported by other investigators (3.2 contacts per person per day); however, 75% of these contacts were for females and consisted mainly of domestic activities occurring around the household. A comparison of the frequency of water contact activities between the direct observation and the two surveys revealed several important points. First, no significant differences were found between methods for routine water contact activities (e.g. bathing), indicating that participants were able to accurately self-report some types of water contact activities. Second, significant differences were found in the recording of water contact activities that took place outside the observation area, indicating that direct observation may under-report water contact activities in areas where contact sites are dispersed widely. Third, significant differences between the direct observation and the survey method were more common for males than for females, indicating that the combination of widespread water contact sites and gender-specific division of labour may result in under-reporting of male contacts by direct observation methods. In short, despite the limitations in the recording of duration and body exposure, the survey method may more accurately record the frequency of water contact activities than direct observation methods in areas of widely dispersed water contact sites. Hence, surveys may be more suitable for the unique challenges of water contact in rural areas of Brazil.


Assuntos
Comportamentos Relacionados com a Saúde , Saúde da População Rural , Esquistossomose mansoni/epidemiologia , Água , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Animais , Banhos , Brasil/epidemiologia , Criança , Pré-Escolar , Feminino , Manipulação de Alimentos , Inquéritos Epidemiológicos , Humanos , Higiene , Lavanderia , Masculino , Pessoa de Meia-Idade , Observação/métodos , Esquistossomose mansoni/parasitologia , Esquistossomose mansoni/transmissão , Fatores Sexuais , Água/parasitologia
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