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2.
Nat Mater ; 20(2): 194-201, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33046856

RESUMO

Topological solitons such as magnetic skyrmions have drawn attention as stable quasi-particle-like objects. The recent discovery of polar vortices and skyrmions in ferroelectric oxide superlattices has opened up new vistas to explore topology, emergent phenomena and approaches for manipulating such features with electric fields. Using macroscopic dielectric measurements, coupled with direct scanning convergent beam electron diffraction imaging on the atomic scale, theoretical phase-field simulations and second-principles calculations, we demonstrate that polar skyrmions in (PbTiO3)n/(SrTiO3)n superlattices are distinguished by a sheath of negative permittivity at the periphery of each skyrmion. This enhances the effective dielectric permittivity compared with the individual SrTiO3 and PbTiO3 layers. Moreover, the response of these topologically protected structures to electric field and temperature shows a reversible phase transition from the skyrmion state to a trivial uniform ferroelectric state, accompanied by large tunability of the dielectric permittivity. Pulsed switching measurements show a time-dependent evolution and recovery of the skyrmion state (and macroscopic dielectric response). The interrelationship between topological and dielectric properties presents an opportunity to simultaneously manipulate both by a single, and easily controlled, stimulus, the applied electric field.

3.
Trop Anim Health Prod ; 52(3): 1073-1079, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31701398

RESUMO

Housing nursery pigs according to body weight is an observed common practice in production systems and, supposedly, improves growth performance and reduces body weight (BW) variation. This 42-day study evaluated the effects of housing nursery pigs according to BW on performance, onset of feed intake, and aggressive behavior. A total of 504 pigs were ranked by BW at weaning and categorized into three groups of 168 pigs each: light, medium, and heavy. Pigs were randomly distributed to unsorted pens (Unsorted) containing 6 pigs of each weight group and sorted pens with 18 pigs from just one group per pen (Sorted). From weaning to day 3, pigs were fed a diet containing 1% iron oxide dye and rectal swabs presenting red coloration were evaluated to assess feed intake onset. Eight pens were video recorded to evaluate aggressive behavior. Sorted-Heavy pigs delayed the onset of feed intake (P ≤ 0.011) and presented more aggressive behaviors than Sorted-Light and Sorted-Medium pigs (P ≤ 0.036). In Unsorted, onset of feed intake showed no differences between weight categories. Also, no differences were observed for aggressive behavior between Sorted and Unsorted. Final BW showed no differences between Sorted and Unsorted pigs. The within-pen weight coefficient variation (CV) was slightly different (P = 0.042) between Sorted and Unsorted pigs (13.3 and 15.6%, respectively), at the end of the study. Thus, sorting nursery pigs by BW did not improve growth performance and also, induce a lag of post-weaning feed intake onset and increased fights in Heavy pigs.


Assuntos
Agressão , Comportamento Animal , Comportamento Alimentar/fisiologia , Abrigo para Animais , Suínos/fisiologia , Ração Animal/análise , Animais , Feminino , Masculino , Suínos/crescimento & desenvolvimento
4.
Nature ; 568(7752): 368-372, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30996320

RESUMO

Complex topological configurations are fertile ground for exploring emergent phenomena and exotic phases in condensed-matter physics. For example, the recent discovery of polarization vortices and their associated complex-phase coexistence and response under applied electric fields in superlattices of (PbTiO3)n/(SrTiO3)n suggests the presence of a complex, multi-dimensional system capable of interesting physical responses, such as chirality, negative capacitance and large piezo-electric responses1-3. Here, by varying epitaxial constraints, we discover room-temperature polar-skyrmion bubbles in a lead titanate layer confined by strontium titanate layers, which are imaged by atomic-resolution scanning transmission electron microscopy. Phase-field modelling and second-principles calculations reveal that the polar-skyrmion bubbles have a skyrmion number of +1, and resonant soft-X-ray diffraction experiments show circular dichroism, confirming chirality. Such nanometre-scale polar-skyrmion bubbles are the electric analogues of magnetic skyrmions, and could contribute to the advancement of ferroelectrics towards functionalities incorporating emergent chirality and electrically controllable negative capacitance.

5.
Sci Adv ; 5(2): eaau7023, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30793029

RESUMO

Researchers have long wondered whether ferroelectrics may present topological textures akin to magnetic skyrmions and chiral bubbles, the results being modest thus far. An electric equivalent of a typical magnetic skyrmion would rely on a counterpart of the Dzyaloshinskii-Moriya interaction and seems all but impossible; further, the exotic ferroelectric orders reported to date rely on specific composites and superlattices, limiting their generality and properties. Here, we propose an original approach to write topological textures in simple ferroelectrics in a customary manner. Our second-principles simulations of columnar nanodomains, in prototype material PbTiO3, show we can harness the Bloch-type structure of the domain wall to create objects with the usual skyrmion-defining features as well as unusual ones-including isotopological and topological transitions driven by external fields and temperature-and potentially very small sizes. Our results suggest countless possibilities for creating and manipulating such electric textures, effectively inaugurating the field of topological ferroelectrics.

6.
Animal ; 12(7): 1380-1387, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29143703

RESUMO

Environmental regulations as well as economic incentives have resulted in greater use of synthetic amino acids in swine diets. Tryptophan is typically the second limiting amino acid in corn-soybean meal-based diets. However, using corn-based co-products emphasizes the need to evaluate the pig's response to increasing Trp concentrations. Therefore, the objective of these studies was to evaluate the dose-response to increasing standardized ileal digestible (SID) Trp : Lys on growth performance of growing-finishing gilts housed under large-scale commercial conditions. Dietary treatments consisted of SID Trp : Lys of 14.5%, 16.5%, 18.0%, 19.5%, 21.0%, 22.5% and 24.5%. The study was conducted in four experiments of 21 days of duration each, and used corn-soybean meal-based diets with 30% distillers dried grains with solubles. A total of 1166, 1099, 1132 and 975 gilts (PIC 337×1050, initially 29.9±2.0 kg, 55.5±4.8 kg, 71.2±3.4 kg and 106.2±3.1 kg BW, mean±SD) were used. Within each experiment, pens of gilts were blocked by BW and assigned to one of the seven dietary treatments and six pens per treatment with 20 to 28 gilts/pen. First, generalized linear mixed models were fit to data from each experiment to characterize performance. Next, data were modeled across experiments and fit competing dose-response linear and non-linear models and estimate SID Trp : Lys break points or maximums for performance. Competing models included broken-line linear (BLL), broken-line quadratic and quadratic polynomial (QP). For average daily gain (ADG), increasing the SID Trp : Lys increased growth rate in a quadratic manner (P<0.02) in all experiments except for Exp 2, for which the increase was linear (P<0.001). Increasing SID Trp : Lys increased (P<0.05) feed efficiency (G : F) quadratically in Exp 1, 3 and 4. For, ADG the QP was the best fitting dose-response model and the estimated maximum mean ADG was obtained at a 23.5% (95% confidence interval (CI): [22.7, 24.3%]) SID Trp : Lys. For maximum G : F, the BLL dose-response models had the best fit and estimated the SID Trp : Lys minimum to maximize G : F at 16.9 (95% CI: [16.0, 17.8%]). Thus, the estimated SID Trp : Lys for 30 to 125 kg gilts ranged from a minimum of 16.9% for maximum G : F to 23.5% for maximum ADG.


Assuntos
Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Suínos , Triptofano , Animais , Dieta , Feminino , Íleo , Lisina/metabolismo , Suínos/crescimento & desenvolvimento , Triptofano/administração & dosagem , Triptofano/farmacologia
7.
Arq. bras. med. vet. zootec. (Online) ; 69(4): 1062-1065, jul.-ago. 2017. tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-876947

RESUMO

The aim of this study was to evaluate a new source of injectable organic zinc (zinc edetate) on the energy and oxidative profile in sheep during the immediate postpartum period. Twenty-six Texel breed animals were previously identified and divided into two experimental groups: the treated group (TG; n= 13) that comprised the animals that received a subcutaneous (SC) injection of 100 mg of zinc edetate (2 mL) fifteen days before the parturition expected date and the control group (CG; n=13) that comprised the animals that received 2mL of physiological solution at the same date of TG. Blood samples were collected on the parturition day for the assessment of serum fructosamine, cholesterol and triglycerides, insulin-like growth factor type 1 (IGF-1), the oxidative stress index (OSi) and blood zinc concentration. In addition to these parameters, the measurement of zinc was made in food given to the animals. There was no difference in metabolic parameters and OSi between the experimental groups (P>0.05), as well as in blood zinc concentrations (P>0.05). The parenteral zinc edentate does not change the energy and oxidative profile of sheep in immediate postpartum.(AU)


Assuntos
Animais , Feminino , Ácido Edético/análise , Metabolismo Energético , Estresse Oxidativo , Período Pós-Parto/metabolismo , Ovinos/metabolismo , Zinco/administração & dosagem
8.
Spectrochim Acta A Mol Biomol Spectrosc ; 172: 156-162, 2017 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-27106811

RESUMO

A new organic compound, guanidinium cyclopropanecarboxylate, has been synthesized and characterized by single crystal X-ray diffraction, infrared spectroscopy and nonlinear optical measurements. The infrared spectrum was calculated with density functional theory (DFT). The second-order NLO response was evaluated with the Kurtz and Perry powder method. From the molecular structure, the molecular hyperpolarizability tensor was determined with Hartree-Fock and DFT methods. The second-order susceptibility tensor of the crystal was evaluated by the summation of the effective hyperpolarizability tensors calculated for the asymmetric unit surrounded by ESP-derived charges.

9.
J Anim Sci ; 94(5): 1940-50, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27285692

RESUMO

Advanced methods for dose-response assessments are used to estimate the minimum concentrations of a nutrient that maximizes a given outcome of interest, thereby determining nutritional requirements for optimal performance. Contrary to standard modeling assumptions, experimental data often present a design structure that includes correlations between observations (i.e., blocking, nesting, etc.) as well as heterogeneity of error variances; either can mislead inference if disregarded. Our objective is to demonstrate practical implementation of linear and nonlinear mixed models for dose-response relationships accounting for correlated data structure and heterogeneous error variances. To illustrate, we modeled data from a randomized complete block design study to evaluate the standardized ileal digestible (SID) Trp:Lys ratio dose-response on G:F of nursery pigs. A base linear mixed model was fitted to explore the functional form of G:F relative to Trp:Lys ratios and assess model assumptions. Next, we fitted 3 competing dose-response mixed models to G:F, namely a quadratic polynomial (QP) model, a broken-line linear (BLL) ascending model, and a broken-line quadratic (BLQ) ascending model, all of which included heteroskedastic specifications, as dictated by the base model. The GLIMMIX procedure of SAS (version 9.4) was used to fit the base and QP models and the NLMIXED procedure was used to fit the BLL and BLQ models. We further illustrated the use of a grid search of initial parameter values to facilitate convergence and parameter estimation in nonlinear mixed models. Fit between competing dose-response models was compared using a maximum likelihood-based Bayesian information criterion (BIC). The QP, BLL, and BLQ models fitted on G:F of nursery pigs yielded BIC values of 353.7, 343.4, and 345.2, respectively, thus indicating a better fit of the BLL model. The BLL breakpoint estimate of the SID Trp:Lys ratio was 16.5% (95% confidence interval [16.1, 17.0]). Problems with the estimation process rendered results from the BLQ model questionable. Importantly, accounting for heterogeneous variance enhanced inferential precision as the breadth of the confidence interval for the mean breakpoint decreased by approximately 44%. In summary, the article illustrates the use of linear and nonlinear mixed models for dose-response relationships accounting for heterogeneous residual variances, discusses important diagnostics and their implications for inference, and provides practical recommendations for computational troubleshooting.


Assuntos
Ração Animal/análise , Modelos Biológicos , Necessidades Nutricionais , Fenômenos Fisiológicos da Nutrição Animal/fisiologia , Animais , Teorema de Bayes , Simulação por Computador , Funções Verossimilhança , Dinâmica não Linear
10.
J Anim Sci ; 94(5): 1993-2003, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27285697

RESUMO

The objective of this study was to determine the effects of AA and energy intake during late gestation on piglet birth weight and reproductive performance of high-performing (14.5 total born) gilts and sows housed under commercial conditions. At d 90 of gestation, a total of 1,102 females (PIC 1050) were housed in pens by parity group (gilts or sows) with approximately 63 gilts and 80 sows in each pen, blocked by BW within each pen, and each female was randomly assigned to dietary treatments within BW block. Dietary treatments consisted of combinations of 2 standardized ileal digestible (SID) AA intakes (10.7 or 20.0 g/d SID Lys and other AA met or exceeded the NRC [2012] recommendations) and 2 energy intakes (4.50 or 6.75 Mcal/d intake of NE) in a 2 × 2 factorial arrangement. Data were analyzed using generalized linear mixed models specified to recognize pen as the experimental unit for parity and the individual female as the experimental unit for dietary treatments. Results indicate an overall positive effect of high energy intake on BW gain during late gestation, although this effect was more manifest under conditions of high, as opposed to low, AA intake (interaction, < 0.001). Furthermore, the magnitude of BW gain response to increased energy intake was greater ( < 0.001) for sows compared with gilts. Sows fed high energy intake had a reduced probability of piglets born alive ( < 0.004) compared with those fed low energy, but no evidence for differences was found in gilts. This can be explained by an increased probability ( = 0.002) of stillborns in sows fed high energy intake vs. sows fed low energy intake. There were no evidences for differences among dietary treatments in litter birth weight and individual piglet birth weight of total piglets born. However, individual born alive birth weight was approximately 30 ± 8.2 g heavier ( = 0.011) for females fed high, as opposed to low, energy intake. Furthermore, piglets born alive were approximately 97 ± 9.5 g heavier ( < 0.001) for sows than for gilts. Preweaning mortality was decreased ( = 0.034) for females fed high AA intake compared with females fed low AA intake regardless of energy level. In conclusion, 1) BW gain of gilts and sows depended not only on energy but also on AA intake, 2) sows fed increased amount of energy had an increased stillborn rate, and 3) increased energy intake during late gestation had a positive effect on individual piglet birth weight with no evidence for such an effect for AA intake.


Assuntos
Dieta/veterinária , Ingestão de Energia/fisiologia , Lactação/fisiologia , Suínos/fisiologia , Aminoácidos , Ração Animal/análise , Criação de Animais Domésticos , Fenômenos Fisiológicos da Nutrição Animal , Animais , Peso ao Nascer/efeitos dos fármacos , Feminino , Íleo , Paridade , Gravidez , Reprodução/fisiologia
11.
J Anim Sci ; 93(8): 3909-18, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26440171

RESUMO

Two experiments were conducted to estimate the standardized ileal digestible (SID) Trp:Lys ratio requirement for growth performance of nursery pigs. Experimental diets were formulated to ensure that lysine was the second limiting AA throughout the experiments. In Exp. 1 (6 to 10 kg BW), 255 nursery pigs (PIC 327 × 1050, initially 6.3 ± 0.15 kg, mean ± SD) arranged in pens of 6 or 7 pigs were blocked by pen weight and assigned to experimental diets (7 pens/diet) consisting of SID Trp:Lys ratios of 14.7%, 16.5%, 18.4%, 20.3%, 22.1%, and 24.0% for 14 d with 1.30% SID Lys. In Exp. 2 (11 to 20 kg BW), 1,088 pigs (PIC 337 × 1050, initially 11.2 kg ± 1.35 BW, mean ± SD) arranged in pens of 24 to 27 pigs were blocked by average pig weight and assigned to experimental diets (6 pens/diet) consisting of SID Trp:Lys ratios of 14.5%, 16.5%, 18.0%, 19.5%, 21.0%, 22.5%, and 24.5% for 21 d with 30% dried distillers grains with solubles and 0.97% SID Lys. Each experiment was analyzed using general linear mixed models with heterogeneous residual variances. Competing heteroskedastic models included broken-line linear (BLL), broken-line quadratic (BLQ), and quadratic polynomial (QP). For each response, the best-fitting model was selected using Bayesian information criterion. In Exp. 1 (6 to 10 kg BW), increasing SID Trp:Lys ratio linearly increased ( 0.05) ADG and G:F. For ADG, the best-fitting model was a QP in which the maximum ADG was estimated at 23.9% (95% confidence interval [CI]: [<14.7%, >24.0%]) SID Trp:Lys ratio. For G:F, the best-fitting model was a BLL in which the maximum G:F was estimated at 20.4% (95% CI: [14.3%, 26.5%]) SID Trp:Lys. In Exp. 2 (11 to 20 kg BW), increasing SID Trp:Lys ratio increased ( 0.05) ADG and G:F in a quadratic manner. For ADG, the best-fitting model was a QP in which the maximum ADG was estimated at 21.2% (95% CI: [20.5%, 21.9%]) SID Trp:Lys. For G:F, BLL and BLQ models had comparable fit and estimated SID Trp:Lys requirements at 16.6% (95% CI: [16.0%, 17.3%]) and 17.1% (95% CI: [16.6%, 17.7%]), respectively. In conclusion, the estimated SID Trp:Lys requirement in Exp. 1 ranged from 20.4% for maximum G:F to 23.9% for maximum ADG, whereas in Exp. 2 it ranged from 16.6% for maximum G:F to 21.2% for maximum ADG. These results suggest that standard recommendations may underestimate the SID Trp:Lys requirement for nursery pigs from 11 to 20 kg BW.


Assuntos
Ração Animal/análise , Íleo/fisiologia , Lisina/química , Suínos/crescimento & desenvolvimento , Triptofano/química , Fenômenos Fisiológicos da Nutrição Animal/fisiologia , Animais , Teorema de Bayes , Peso Corporal , Dieta/veterinária , Feminino , Lisina/metabolismo , Masculino , Suínos/fisiologia , Triptofano/fisiologia
12.
J Anim Sci ; 93(3): 1098-102, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26020886

RESUMO

A total of 180 nursery pigs (PIC 327 × 1050; initially 12.6 kg) were used in an 18-d study to determine the effects of pellet mill conditioning parameters and feed form on pig performance. All diets were similar, and different feed processing parameters were used to create experimental treatments. Factors considered were conditioning time (15, 30, or 60 s) and feed form (mash or pelleted). To remove the confounding factor of feed form, pelleted samples were reground to a similar particle size as the mash diet. Treatments included: 1) mash diet without thermal processing (negative control), 2) pelleted diet conditioned for 30 s (positive control), 3) pelleted diet conditioned for 15 s and reground, 4) pelleted diet conditioned for 30 s and reground, and 5) pelleted diet conditioned for 60 s and reground. Pigs were weaned and fed a common acclimation diet for 21 d before the start of the experiment. Growth and feed disappearance were then measured for 18 d. All diets had similar levels of percentage total starch, but thermally processed diets had a 1.67 to 1.87-fold increase in percentage gelatinized starch compared to the mash diet. Average daily gain and G:F did not differ between treatments overall, but pigs fed the positive control pelleted diet had decreased ADFI ( < 0.05) compared to pigs fed all other diets. Preplanned contrasts revealed that pigs fed mash diets tended to have greater ADG ( < 0.10) compared to those fed pelleted and reground diets. This suggests that processing may have had a negative influence on feed utilization, which is further supported by the finding that pigs fed mash diets tended to have greater ADG ( < 0.10) compared to those fed diets that were thermally processed, regardless of regrinding. Considering these results, it was not surprising that pigs fed mash diets had greater ADG and ADFI ( < 0.05) than those fed pelleted diets. When directly comparing diets conditioned at 60 rpm, fed either as whole pellets or reground to mash consistency, pigs fed pelleted diets had improved G:F ( < 0.05) due to lower ADFI ( < 0.05) but similar ADG. The expected improvement in G:F from pelleting (6.8%) was observed but lost when diets were reground to near original mash particle size. This may indicate that diet form from the actual pelleting process impacts G:F more than conditioner retention time.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal/fisiologia , Animais Recém-Nascidos/crescimento & desenvolvimento , Manipulação de Alimentos/métodos , Abrigo para Animais , Condicionamento Físico Animal , Suínos/crescimento & desenvolvimento , Ração Animal/análise , Animais , Animais Recém-Nascidos/fisiologia , Dieta/veterinária , Feminino , Masculino , Tamanho da Partícula , Suínos/fisiologia , Fatores de Tempo , Desmame , Aumento de Peso/fisiologia
13.
Clin Microbiol Infect ; 20(5): 447-52, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24033793

RESUMO

Leprosy epidemiological studies have been restricted to Mycobacterium leprae DNA detection in nasal and oral mucosa samples with scarce literature on peripheral blood. We present the largest study applying quantitative real-time PCR (qPCR) for the detection of M. leprae DNA in peripheral blood samples of 200 untreated leprosy patients and 826 household contacts, with results associated with clinical and laboratory parameters. To detect M. leprae DNA a TaqMan qPCR assay targeting the M. leprae ML0024 genomic region was performed. The ML0024 qPCR in blood samples detected the presence of bacillus DNA in 22.0% (44/200) of the leprosy patients: 23.2% (16/69) in paucibacillary (PB), and 21.4% (28/131) in multibacillary (MB) patients. Overall positivity among contacts was 1.2% (10/826), with similar percentages regardless of whether the index case was PB or MB. After a follow-up period of 7 years, 26 contacts have developed leprosy. Comparing the results of healthy contacts with those that become ill, ML0024 qPCR positivity at the time of diagnosis of their index case represented an impressive 14.78-fold greater risk for leprosy onset (95% CI 3.6-60.8; p <0.0001). In brief, contacts with positive PCR in blood at diagnosis of index cases are at higher risk of later leprosy onset and this marker might be combined with other prognostic markers for management of contacts, which requires further studies.


Assuntos
DNA Bacteriano/sangue , Hanseníase Multibacilar/sangue , Hanseníase Multibacilar/transmissão , Hanseníase Paucibacilar/sangue , Hanseníase Paucibacilar/transmissão , Mycobacterium leprae/genética , Proteínas de Bactérias/genética , Portador Sadio/sangue , Seguimentos , Humanos , Hanseníase Multibacilar/epidemiologia , Hanseníase Paucibacilar/epidemiologia , Mycobacterium leprae/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real , Fatores de Risco
14.
Public Health ; 125(7): 464-75, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21722930

RESUMO

OBJECTIVE: Worldwide, genital warts, caused by human papillomavirus (HPV) is a common, sexually transmitted disease. The overall disease management strategy for genital warts should be determined not only by the prevalence, but also by the impact of the disease on individuals and society. The purpose of this study was therefore to investigate the epidemiological, economic and quality of life (QoL) burden of genital warts. METHODS: A systematic literature review was conducted on the epidemiology, QoL and management cost of genital warts in the USA, UK and France, based on studies published between 1998 and 2008. Due to scarcity of data, all studies reporting standardized QoL assessments among patients with genital warts were utilized, regardless of country of origin. Original studies were preferred over information cited in review articles. RESULTS: Data from three countries suggest that genital warts occur in 0.06-0.23% of the population each year. Despite the fact that spontaneous remissions occur frequently (up to 40%), patients often prefer immediate treatment. While treatment can be costly in absolute terms (€163-510 per treatment episode), these costs are lower compared with other sexually transmitted infections (STIs). Modest reductions in QoL have been noted, which may be mitigated through adequate patient education and support. CONCLUSIONS: While genital warts are an inconvenience for many patients, the occurrence may be lower than often quoted in the literature, and the economic burden on society is less than for other prominent STIs. However, concerted efforts to establish improved data collection and surveillance systems are needed in order to accurately define the burden of genital warts on individuals and society.


Assuntos
Condiloma Acuminado , Qualidade de Vida , Condiloma Acuminado/economia , Condiloma Acuminado/epidemiologia , Condiloma Acuminado/fisiopatologia , Efeitos Psicossociais da Doença , Feminino , França/epidemiologia , Humanos , Incidência , Masculino , Prevalência , Reino Unido/epidemiologia , Estados Unidos/epidemiologia
15.
Clin Microbiol Infect ; 17(11): 1653-8, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21199152

RESUMO

Leprosy is an important health problem in Brazil despite extensive use of multidrug therapy. The nasal mucosa is the preferential site of entry and exit of Mycobacterium leprae, and although lesions have been found in the oral mucosa, its potential involvement in the transmission of leprosy bacilli has never been investigated. We investigated the presence of the M. leprae DNA in buccal swabs of leprosy patients (334) and household contacts (1288) through polymerase chain reaction (PCR), and correlated this with clinical and laboratorial evaluations. The overall positivity for patients and contacts was 18.26% and 6.83%, respectively. Subclinical infection among contacts was considered when PCR and anti-PGL-1 ELISA presented positive results. This study provides evidence that the oral mucosa may be a secondary site of M. leprae transmission and infection, and contacts with bacillary DNA may be actively involved in transmission. We have also shown that bacilli DNA is more frequently found in the oral mucosa of PB patients. Our findings have great epidemiological relevance and indicate an additional strategy for leprosy control programmes and dental clinics.


Assuntos
DNA Bacteriano/isolamento & purificação , Hanseníase/diagnóstico , Hanseníase/microbiologia , Mucosa Bucal/microbiologia , Mycobacterium leprae/isolamento & purificação , Adulto , Anticorpos Antibacterianos/sangue , Brasil , Estudos Transversais , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mycobacterium leprae/genética , Mycobacterium leprae/imunologia , Reação em Cadeia da Polimerase
16.
Braz J Biol ; 69(1): 171-4, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19347161

RESUMO

Causes and implications of sexual dimorphism have been studied in several different primates using a variety of morphological characters such as body weight, canine length, coat color and ornamentation. Here we describe a peculiar coat color characteristic in the squirrel monkey that is present only in adult females over five years old and which increases with age. Neither males nor young animals manifest this phenomenon, which is characterized by a spot of black hairs located anteriorly to the external ear (pinna). This characteristic could be used to discriminate adult females of Saimiri sciureus in the wild without the need of capture techniques.


Assuntos
Cor de Cabelo , Saimiri/anatomia & histologia , Caracteres Sexuais , Animais , Feminino , Masculino
17.
Braz. j. biol ; 69(1): 171-174, Feb. 2009. ilus
Artigo em Inglês | LILACS | ID: lil-510138

RESUMO

Causes and implications of sexual dimorphism have been studied in several different primates using a variety of morphological characters such as body weight, canine length, coat color and ornamentation. Here we describe a peculiar coat color characteristic in the squirrel monkey that is present only in adult females over five years old and which increases with age. Neither males nor young animals manifest this phenomenon, which is characterized by a spot of black hairs located anteriorly to the external ear (pinna). This characteristic could be used to discriminate adult females of Saimiri sciureus in the wild without the need of capture techniques.


As causas e implicações do dimorfismo sexual têm sido estudadas em diferentes espécies de primatas utilizando uma variedade de características morfológicas tais como peso corporal, comprimento de caninos, coloração do pelo e ornamentação. Este trabalho descreve uma característica peculiar da coloração do pelo em micos-de-cheiro, que está presente somente em fêmeas adultas após cinco anos de idade e que se acentua com a idade. Nem machos nem animais jovens manifestam esse fenômeno, que se caracteriza por uma mancha de pelos pretos localizada anteriormente à orelha. Esta característica poderia ser usada para discriminar fêmeas adultas de Saimiri sciureus na natureza sem necessidade de técnicas de captura.


Assuntos
Animais , Feminino , Masculino , Cor de Cabelo , Caracteres Sexuais , Saimiri/anatomia & histologia
18.
J Clin Microbiol ; 43(8): 3932-7, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16081933

RESUMO

Infection with oncogenic human papillomavirus (HPV) is considered to be the major risk factor for cervical cancer. Tumor necrosis factor (TNF) is a pluripotent cytokine that plays an important role in inhibiting the action of microbial agents, and TNF microsatellite polymorphisms have been associated with several diseases, including cancer and viral infections. This study analyzed the associations between TNFa to -e microsatellite polymorphisms and the severity of squamous intraepithelial lesions (SIL), according to the presence of the oncogenic HPV16 and HPV18 types. Samples from 146 HPV-positive women with low-grade SIL (LSIL) and high-grade SIL (HSIL) and samples from 101 healthy women were studied. TNF microsatellite polymorphism typing and HPV detection and typing were performed using PCR-amplified DNA hybridized with sequence-specific primers. Data were analyzed by Fisher's exact test using the GENEPOP software. Significant associations were observed between LSIL and the TNFa-8 allele (4/166; P = 0.04), as well as between TNFa-2 with HPV18 only (16/44; P = 0.002) and TNFa-2 with HPV18 coinfection with HPV16 (16/44; P = 0.001). Patients exhibiting the TNFa-2 allele and harboring HPV18, in the presence or absence of coinfection with HPV16, had an increased risk of HSIL occurrence (13/38; P = 0.04; 5/10; P = 0.04) compared to patients with other HPV types. These results suggest that the TNFa-8 allele is associated with increased susceptibility to the occurrence of LSIL and that despite the presence of a high TNF-alpha production allele, the ability of HPV18 to resist the inhibitory effects of TNF-alpha may contribute to the occurrence of infection and consequently to HSIL in women with cervical HPV18 infection.


Assuntos
Alelos , Repetições de Microssatélites , Papillomaviridae , Infecções por Papillomavirus/genética , Lesões Pré-Cancerosas/genética , Fator de Necrose Tumoral alfa/genética , Neoplasias do Colo do Útero/genética , Adolescente , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Infecções por Papillomavirus/etiologia , Lesões Pré-Cancerosas/etiologia , Neoplasias do Colo do Útero/etiologia
19.
Sleep Med ; 6(4): 333-9, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15946896

RESUMO

BACKGROUND AND PURPOSE: To evaluate the effect of one month of continuous positive airway pressure (CPAP) in a subgroup of obstructive sleep apnea (OSA) patients with erectile dysfunction (ED) and compare this subgroup with age- and body mass index (BMI)-matched OSA patients without ED. PATIENTS AND METHODS: Prospective general, sleep, psychiatric and sexologic evaluations were conducted. Epworth Sleepiness Scale (ESS), Beck Depression Inventory (BDI), Sleep Disorders Questionnaire (SDQ), Quality of Life SF-36, and polysomnography were used. Seventeen OSA patients with ED were compared prior to CPAP treatment and during CPAP treatment with age- and BMI-matched OSA patients without ED. Parametric and non-parametric statistics, chi-square, Fisher exact test and multiple regression analyses were performed. RESULTS: Ninety-eight men (BMI=28.8 kg/m2, apnea-hypopnea index (AHI)=49.6 events/h, ESS=14.8, BDI=8.4, and lowest SaO2=75.3%) were divided into subgroups of lowest SaO2>80% (A) and lowest SaO2< or =80% (B). (A) Forty-six men had a mean lowest SaO2 of 85.7%+/-2.9, AHI=29.5+/-17.6, age=46.3+/-9.3 years, ESS=13.6+/-4.2, BMI=25.8+/-4.8. Seven of the patients had ED. (B) Fifty-two men had a mean lowest SaO2=60.10+/-10.0%, AHI=67.4+/-24.5, BDI=9.0+/-6.9, age=47.4+/-9.4 years, ESS=16.2+/-4.4, BMI=31.4+/-5.1. Twenty-one of the patients had ED (chi2: P=0.006). Significant variables for ED were lowest SaO2 and age (r=0.17). CPAP-treated subgroup: ED subjects had significantly lower SaO2, ESS, BDI and SF-36 subscale scores than OSA controls. Nasal CPAP eliminated the differences between groups, and ED was resolved in 13 out of 17 cases. CONCLUSIONS: ED in OSAS is related to nocturnal hypoxemia, and about 75% of OSAS patients with ED treated with nasal CPAP showed remission at one-month follow-up, resulting in significant improvement in quality of life.


Assuntos
Pressão Positiva Contínua nas Vias Aéreas/métodos , Disfunção Erétil/epidemiologia , Apneia Obstrutiva do Sono/epidemiologia , Apneia Obstrutiva do Sono/terapia , Índice de Massa Corporal , Humanos , Masculino , Pessoa de Meia-Idade , Polissonografia , Estudos Prospectivos , Qualidade de Vida/psicologia , Apneia Obstrutiva do Sono/diagnóstico
20.
J Psychosom Res ; 56(5): 511-5, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15172207

RESUMO

OBJECTIVE: To prospectively evaluate the relationship between obstructive sleep apnea syndrome (OSAS), nocturia and quality of life in elderly patients free of the urologic and medical conditions that lead to increased nocturia. METHODS: Prospective study of nocturia in men 65 years and older with isolated OSAS or sleep onset insomnia. After a 7-day nocturia evaluation and nocturnal polysomnography, Epworth Sleepiness Scale (ESS), Beck Depression Inventory (BDI), Quality of Life (SF-36) were administered. RESULTS: OSAS patients with frequent nocturia had significantly greater body mass index (BMI), greater apnea-hypopnea index (AHI), lower lowest oxygen saturation and lower SF-36 subscale scores. Treatment with nasal continuous positive airway pressure (CPAP) for OSAS and behavioral techniques for insomnia improved ESS and BDI scores for all three groups. SF-36 subscale scores improved more in subjects with multiple nocturia. AHI and BMI explain 38% of the variance for nocturia. CONCLUSION: Nasal CPAP reduces OSA and nocturia and improves quality of life of elderly patients.


Assuntos
Respiração com Pressão Positiva , Qualidade de Vida , Síndromes da Apneia do Sono/psicologia , Síndromes da Apneia do Sono/terapia , Distúrbios do Início e da Manutenção do Sono/complicações , Distúrbios do Início e da Manutenção do Sono/psicologia , Transtornos Urinários/etiologia , Transtornos Urinários/psicologia , Idoso , Biorretroalimentação Psicológica , Humanos , Masculino , Pacientes Ambulatoriais , Estudos Prospectivos , Síndromes da Apneia do Sono/complicações , Resultado do Tratamento
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