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1.
Fungal Genet Biol ; 164: 103765, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36528339

RESUMO

The production of yeast oil from lignocellulosic biomasses is impaired by inhibitors formed during the pretreatment step, mainly acetic acid. Herein, we applied Adaptive Laboratory Evolution (ALE) to select three Acetic acid Tolerant Strains (ATS) of P. laurentii UFV-1. Different phenotypes emerged alongside evolution. The ATS II presented trade-offs in the absence of acetic acid, suggesting that it displays a specialized phenotype of tolerance to growth on organic acids. On the other hand, ATS I and ATS III presented phenotypes associated with the behavior of generalists. ATS I was considered the most promising evolved strain as it displayed the oleaginous phenotype in all conditions tested. Thus, we applied whole-genome sequencing to detect the mutations that emerged in this strain during the ALE. We found alterations in genes encoding proteins involved in different cellular functions, including multidrug resistance (MDR) transporters, energy metabolism, detoxification, coenzyme recycling, and cell envelope remodeling. To evaluate acetic acid stress responses, both parental and ATS I strains were cultivated in chemostat mode in the absence and presence of acetic acid. In contrast to ATS I, the parental strain presented alterations in the cell envelope and cell size under acetic acid stress conditions. Furthermore, the parental strain and the ATS I presented differences regarding acetic acid assimilation. Contrary to the parental strain, the ATS I displayed an increase in unsaturated fatty acid content irrespective of acetic acid stress, which might be related to improved tolerance to acetic acid. Altogether, these results provided insights into the mechanisms involved with the acetic acid tolerance displayed by ATS I and the responses of P. laurentii to this stressful condition.


Assuntos
Ácido Acético , Saccharomyces cerevisiae , Ácido Acético/farmacologia , Ácido Acético/metabolismo , Saccharomyces cerevisiae/genética , Fenótipo , Proteínas de Membrana Transportadoras/genética
2.
BMC Med Educ ; 20(1): 449, 2020 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-33225951

RESUMO

BACKGROUND: Electives are perceived by medical students as a valuable, highly regarded experience, allowing them to customize learning experiences and enabling them to early differentiate during medical training. The present work aims to uncover students' major determinants of satisfaction and how they interfere with their future elective choices in order to identify the best approach to implement electives in medical curricula. METHODS: A cross-sectional study was conducted through a written evaluation survey concerning the electives available in the academic year 2015-2016. Our institution provides 106 electives to students from the 2nd to the 5th year. Students' satisfaction was assessed through a validated questionnaire with eight sentences expressing opinions related to electives global satisfaction. Data from 538 inquiries from 229 students were analyzed quantitatively using regression and correlation models, and qualitatively through phenomenography. RESULTS: Quantitative analysis of the questionnaires allowed to establish both: 1) The determinants of students' satisfaction with electives, which were Agreement with teaching and learning methodologies, followed by Agreement with assessment methodologies employed, Perception of the workload demanded and Requirement for continuous work and 2) The predictors of students preferences in the following years, namely, Agreement with assessment methodologies employed, Classes attendance and Ranking of the allocated elective established in the previous year. Qualitative analysis of questionnaires revealed that students consider electives as being innovative and interesting, claiming that some, for their relevant content, could be integrated into the medical core curriculum. CONCLUSIONS: Our work raises awareness on the best practices when it comes to electives' organization to meet students' satisfaction. We can conclude that medical schools should measure students satisfaction as a tool to organize and predict future needs of electives and placements when designing and implementing this alternative student-centred curriculum or even to improve the existing practices regarding electives in medical courses.


Assuntos
Educação de Graduação em Medicina , Estudantes de Medicina , Estudos Transversais , Currículo , Humanos , Satisfação Pessoal
3.
Int Nurs Rev ; 66(2): 280-289, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30815859

RESUMO

AIM: To examine situations of vulnerability to human papillomavirus in the social representations of young women. BACKGROUND: Human papillomavirus is one of the most frequent sexually transmitted infections among women and constitutes a serious health problem among youth. This problem is embedded in psychosocial issues that promote situations of vulnerability and affect attitudes and behaviour in relation to prevention. METHODS: Qualitative study based on the theory of social representations, conducted among 64 female students in a high school in the city of Rio de Janeiro, Brazil. The study used personal semi-structured interviews, with a lexical analysis by Alceste 2010 software. FINDINGS: The inefficacy of information on the human papillomavirus pointed out individual and social vulnerabilities, and showed relationships between the difficulty of access and the perception of low quality in public health services, which also promotes institutional vulnerability. DISCUSSION: The representation of vulnerability to human papillomavirus infection is associated, not only with individual behaviours related to sexuality and gender identity but also to social and institutional conditions involving insufficient information and low quality of and ineffective access to public health services. CONCLUSION: Situations of vulnerability of young women to human papillomavirus infection influence ways of thinking and acting, when they generate feelings and behaviours that put them at risk. The social representations provided knowledge about how the participants appropriated consensual and reified universes in relation to vulnerability, influencing care and awareness of prevention. IMPLICATION FOR NURSING AND HEALTH POLICY: Situations of vulnerability, whether individual, social or institutional, warrant the attention of nurses and should be prioritized as public health policy goals to reduce the number of cases of human papillomavirus infection among younger women.


Assuntos
Comportamento do Adolescente/psicologia , Conhecimentos, Atitudes e Prática em Saúde , Acessibilidade aos Serviços de Saúde , Infecções por Papillomavirus/psicologia , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Adolescente , Brasil , Feminino , Humanos , Infecções por Papillomavirus/prevenção & controle , Comportamento Sexual/psicologia
4.
Allergy ; 73(7): 1470-1478, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29337345

RESUMO

BACKGROUND: In mouse models of allergic asthma, exposure to different allergens can trigger distinct inflammatory subtypes in the airways. We investigated whether this observation extends to humans. METHODS: We compared the frequency of sputum inflammatory subtypes between mild allergic asthma subjects (n = 129) exposed to different allergens in inhalation challenge tests. These tests were performed using a standardized protocol as part of clinical trials of experimental treatments for asthma, prior to drug randomization. Five allergen types were represented: the house dust mites Dermatophagoides pteronyssinus and Dermatophagoides farinae, ragweed, grass, and cat. RESULTS: Of 118 individuals with a sputum sample collected before allergen challenge (baseline), 45 (38%) had paucigranulocytic, 51 (43%) eosinophilic, 11 (9%) neutrophilic, and 11 (9%) mixed granulocytic sputum. Of note, most individuals with baseline paucigranulocytic sputum developed eosinophilic (48%) or mixed granulocytic (43%) sputum 7 hours after allergen challenge, highlighting the dynamic nature of sputum inflammatory subtype in asthma. Overall, there was no difference in the frequency of sputum inflammatory subtypes following challenge with different allergen types. Similar results were observed at 24 hours after allergen challenge. CONCLUSIONS: Unlike reported in mice, in humans the sputum inflammatory subtype observed after an allergen-induced asthma exacerbation is unlikely to be influenced by the type of allergen used.


Assuntos
Alérgenos/imunologia , Hipersensibilidade/diagnóstico , Hipersensibilidade/imunologia , Escarro/citologia , Escarro/imunologia , Alérgenos/administração & dosagem , Animais , Asma/diagnóstico , Asma/imunologia , Testes de Provocação Brônquica , Granulócitos/imunologia , Granulócitos/metabolismo , Humanos , Imunização , Imunoglobulina E/imunologia , Camundongos , Estudos Retrospectivos , Testes Cutâneos
5.
J Dairy Sci ; 101(7): 6055-6065, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29605314

RESUMO

This experiment aimed to evaluate the effects of supplying 4 different inclusion levels of Met + Cys to crossbred liquid-fed calves on animal performance and body composition. Thirty-six Holstein-Gyr male calves were separated into 2 age groups: 16 calves, slaughtered at an age of 30 d, representing the physiological phase from 8 to 30 d, and 20 calves, slaughtered at an age of 60 d, representing the physiological phase from 30 to 60 d. At 8 d of age, the animals were randomly distributed among the experimental treatments: 4 Met + Cys inclusion levels (Met + Cys: 8.0, 8.7, 9.4, and 10.2 g/d), provided by an AA supplement added to 1.0 kg (as fed) of commercial milk replacer containing soy protein concentrate and wheat protein isolate reconstituted at 13.8% (dry matter basis). The diet was supplied without allowing leftovers and no starter feed was provided. The experimental diets were supplied without allowing orts, so that the dry matter, crude protein, and ether extract intakes were the same for all animals, independent of Met + Cys level. Total weight gain, average daily gain, gain composition, and body composition were evaluated for both age groups separately. Digestibility of organic matter, crude protein, and ether extract was lower for 8 to 30 d than for 30 to 60 d. The effect of Met + Cys levels on the digestibility of nutrients was not observed; there also was no significant interaction between physiological phase and Met + Cys levels. For the 8 to 30 d group, no responses in performance were observed according to the different Met + Cys levels, which indicates that 8.0 g/d of Met + Cys met the requirements for this physiological phase. The 30 to 60 d group responded positively to higher Met + Cys inclusion in the diet. In conclusion, an optimal Met + Cys dietary level to ensure best performance and protein gain ranges from 8.41 to 9.81 g/d.


Assuntos
Composição Corporal/efeitos dos fármacos , Bovinos/crescimento & desenvolvimento , Cisteína/farmacologia , Metionina/farmacologia , Ração Animal , Animais , Composição Corporal/fisiologia , Cisteína/administração & dosagem , Dieta , Masculino , Metionina/administração & dosagem , Leite , Substitutos do Leite/metabolismo , Desmame
6.
BMC Med Educ ; 18(1): 94, 2018 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-29724217

RESUMO

BACKGROUND: The aim of this review was to identify studies exploring neuroanatomy teaching tools and their impact in learning, as a basis towards the implementation of a neuroanatomy program in the context of a curricular reform in medical education. METHODS: Computer-assisted searches were conducted through March 2017 in the PubMed, Web of Science, Medline, Current Contents Connect, KCI and Scielo Citation Index databases. Four sets of keywords were used, combining "neuroanatomy" with "education", "teaching", "learning" and "student*". Studies were reviewed independently by two readers, and data collected were confirmed by a third reader. RESULTS: Of the 214 studies identified, 29 studies reported data on the impact of using specific neuroanatomy teaching tools. Most of them (83%) were published in the last 8 years and were conducted in the United States of America (65.52%). Regarding the participants, medical students were the most studied sample (37.93%) and the majority of the studies (65.52%) had less than 100 participants. Approximately half of the studies included in this review used digital teaching tools (e.g., 3D computer neuroanatomy models), whereas the remaining used non-digital learning tools (e.g., 3D physical models). CONCLUSIONS: Our work highlight the progressive interest in the study of neuroanatomy teaching tools over the last years, as evidenced from the number of publications and highlight the need to consider new tools, coping with technological development in medical education.


Assuntos
Aprendizagem , Neuroanatomia/educação , Materiais de Ensino , Humanos , Neuroanatomia/tendências , Estudantes de Medicina
7.
Clin Exp Allergy ; 47(2): 217-223, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27883235

RESUMO

BACKGROUND: Genetic variants for IgE-mediated peanut allergy are yet to be fully characterized and to date only one genomewide association study (GWAS) has been published. OBJECTIVE: To identify genetic variants associated with challenge-proven peanut allergy. METHODS: We carried out a GWAS comparing 73 infants with challenge-proven IgE-mediated peanut allergy against 148 non-allergic infants (all ~ 1 year old). We tested a total of 3.8 million single nucleotide polymorphisms, as well as imputed HLA alleles and amino acids. Replication was assessed by de novo genotyping in a panel of additional 117 cases and 380 controls, and in silico testing in two independent GWAS cohorts. RESULTS: We identified 21 independent associations at P ≤ 5 × 10-5 but were unable to replicate these. The most significant HLA association was the previously reported amino acid variant located at position 71, within the peptide-binding groove of HLA-DRB1 (P = 2 × 10-4 ). Our study therefore reproduced previous findings for the association between peanut allergy and HLA-DRB1 in this Australian population. CONCLUSIONS AND CLINICAL RELEVANCE: Genetic determinants for challenge-proven peanut allergy include alleles at the HLA-DRB1 locus.


Assuntos
Substituição de Aminoácidos , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Cadeias HLA-DRB1/genética , Hipersensibilidade a Amendoim/genética , Hipersensibilidade a Amendoim/imunologia , Polimorfismo Genético , Alelos , Genótipo , Cadeias HLA-DRB1/química , Cadeias HLA-DRB1/imunologia , Humanos , Razão de Chances , Polimorfismo de Nucleotídeo Único
8.
Genet Mol Res ; 16(3)2017 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-28873211

RESUMO

Taking into account the scenario of melon production (Cucumis melo L.) in Brazil, it is notable the importance of the culture in the fruit market. The preference of the national market is concentrated in the fruits of the yellow type. Therefore, it is possible that the genetic base of the commercial cultivars is relatively narrow due to the loss of important genes in the breeding process, and it is possible to introgress external genes for increasing recombination possibilities that generate sources of resistance to the main diseases and superior genotypes. This study evaluated the genetic variability of 87 melon accessions composed of 72 commercial cultivars belonging to the Inodorus and Cantaloupensis groups and 15 plant introductions (PIs). Forty-four polymorphic SSR primers were used to amplify a total of 202 alleles. The expected heterozygosity presented an average of 0.519 and the PIC index of 0.458, being moderately informative. The dendrogram generated for the 72 cultivars grouped the genotypes into 2 main groups, and there was no association with the classification of groups of the genotypes in the grouping. The number of SSR markers was sufficient to predict wide genetic variability among the cultivars studied, with the similarity between 0.35 and 0.98. The dendrogram presented for the 72 cultivars and the 15 PI genotypes was not associated with the classification of the genotypes in the grouping, and the 15 PIs were well dispersed with similarity indexes that resemble the two groups studied. A set of 25 primers was identified that were useful in distinguishing the 72 cultivars. These primers can be used in later research with the cultivars, as well as in crop protection situations, being an important tool in the useful and rapid distinction of genotypes, and in commercial disputes regarding the certification of the main melon cultivars used in the country.


Assuntos
Cucurbitaceae/genética , Repetições de Microssatélites , Polimorfismo Genético , Alelos , Genótipo , Heterozigoto
9.
BMC Med Educ ; 17(1): 9, 2017 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-28086868

RESUMO

BACKGROUND: In higher education, the focus has shifted from the acquisition of knowledge to learning objectives and skills. This means that, the majority of student learning time is spent independently working outside the classroom. Students take an active role in setting goals, deciding how to achieve them, and planning individual study time. Although extensive research has recognized the importance of curriculum and students' characteristics in time devoted to self-study, it is still unclear to what extent these variables affect time to study. Due to the growing reliance on self-directed learning in medical education, and in an attempt to elucidate this issue, this research aims to evaluate self-study time during clinical training and assess whether this is more influenced by the student or the curriculum. METHODS: A questionnaire was given to 1220 medical students (43.3% of the enrolled students). The students were asked to indicate the average number of study hours per week beyond the time allocated to classes for each clerkship (rotation) attended. Variation and generalizability of students' self-study were estimated using linear mixed models. RESULTS: Findings showed that the intrinsic differences within students were a greater source of variation in self-study time than differences within clerkships (56.0% vs. 6.9%). If the amount of self-study dedicated to an individual clerkship is to be determined, at least 32 students are needed to achieve acceptable reliability. However, this data with two clerkships per student can used to retrospectively measure the self-study reported by students in clinical training. CONCLUSIONS: The findings suggest that, both, curriculum and student characteristics influence self-study in undergraduate clinical training. Indeed, students' characteristics play a significant role in time devoted to study. Further research should be undertaken to investigate students' characteristics that may predict self-study during undergraduate medical training.


Assuntos
Estágio Clínico/métodos , Currículo , Educação Médica/métodos , Aprendizagem , Estudantes de Medicina/psicologia , Atitude do Pessoal de Saúde , Estágio Clínico/normas , Competência Clínica/normas , Educação Médica/normas , Docentes de Medicina , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Portugal , Estudantes de Medicina/estatística & dados numéricos , Inquéritos e Questionários , Ensino , Fatores de Tempo , Carga de Trabalho
10.
J Fish Biol ; 90(3): 1062-1069, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28181239

RESUMO

A total of 1006 duck catfish Ageneiosus ucayalensis were collected from a ria river system of eastern Amazonia, of which 733 were females and 273 males, a sex ratio 2·69:1. Condition factors of males were higher than those of females and size at first sexual maturity (L50 ) was 12·8 cm for females and 11·8 cm for males. The relative frequency of mature specimens and gonad condition indices indicate that the breeding season is short and coincides with the rainy season.


Assuntos
Peixes-Gato/fisiologia , Rios , Animais , Brasil , Feminino , Masculino , Reprodução , Estações do Ano , Maturidade Sexual/fisiologia
11.
J Fish Biol ; 91(1): 346-353, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28543076

RESUMO

This study evaluated the reproductive characteristics of pike-characids, Boulengerella cuvieri, during the hydrological cycle in the Xingu River, eastern Amazon. The sex ratio was 1:1 and the gonado-somatic index and relative frequency of maturation stages indicate a short breeding season of single phase spawning that coincides with a filling and flood period. Mean standard length at first sexual maturity for female B. cuvieri was estimated to be 22·9 cm.


Assuntos
Caraciformes/fisiologia , Reprodução/fisiologia , Animais , Brasil , Feminino , Inundações , Masculino , Rios , Estações do Ano , Razão de Masculinidade , Maturidade Sexual
12.
J Food Sci Technol ; 54(13): 4344-4352, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29184240

RESUMO

Most studies evaluating the use of essential oils (EO) as antibacterial agents focus mainly on minimal inhibitory concentrations (MIC) rather than minimal bactericidal concentrations (MBC). In this work, we compared MICs and MBCs of EO from condiment plants commonly used in Mediterranean Europe, namely Origanum vulgare, Salvia lavandulaefolia, Salvia officinalis, Salvia sclarea and Rosmarinus officinalis, aiming to evaluate their application as disinfecting agents in minimally processed produce. Outbreaks-related pathogens such as Listeria monocytogenes, Pseudomonas aeruginosa and Yarrowia lipolytica were used. Results showed that all EO were able to reduce bacterial growth in all bacterial strains tested, particularly O. vulgare. However, fewer EO exhibited bactericidal activities, and were only effective against one or two bacterial strains, hence eliminating the possibility to use them as broad range disinfectants. Furthermore, the necessary concentrations were too high for food application. Hence, our work suggests the need to evaluate MBC rather than MIC and questions EO usefulness in controlling undesired microorganisms. Overall, and despite the large volume of data published on EO, results obtained were not very encouraging for a realistic application on produce and question the viability of EOs as disinfecting agents in food.

13.
Allergy ; 71(7): 1020-30, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26932604

RESUMO

BACKGROUND: Functional variants in the interleukin-6 receptor gene (IL6R) are associated with asthma risk. We hypothesized that genes co-expressed with IL6R might also be regulated by genetic polymorphisms that are associated with asthma risk. The aim of this study was to identify such genes. METHODS: To identify genes whose expression was correlated with that of IL6R, we analyzed gene expression levels generated for 373 human lymphoblastoid cell lines by the Geuvadis consortium and for 38 hematopoietic cell types by the Differentiation Map Portal (DMAP) project. Genes correlated with IL6R were then screened for nearby single nucleotide polymorphisms (SNPs) that were significantly associated with both variation in gene expression levels (eSNPs) and asthma risk. RESULTS: We identified 90 genes with expression levels correlated with those of IL6R and that also had a nearby eSNP associated with disease risk in a published asthma GWAS (N = 20 776). For 16 (18%) genes, the association between the eSNP and asthma risk replicated with the same direction of effect in a further independent published asthma GWAS (N = 27 378). Among the top replicated associations (FDR < 0.05) were eSNPs for four known (IL18R1, IL18RAP, BCL6, and STAT6) and one putative novel asthma risk gene, stomatin-like protein 2 (STOML2). The expression of STOML2 was negatively correlated with IL6R, while eSNPs that increased the expression of STOML2 were associated with an increased asthma risk. CONCLUSION: The expression of STOML2, a gene that plays a key role in mitochondrial function and T-cell activation, is associated with both IL-6 signaling and asthma risk.


Assuntos
Asma/genética , Proteínas Sanguíneas/genética , Estudos de Associação Genética , Predisposição Genética para Doença , Proteínas de Membrana/genética , Receptores de Interleucina-6/genética , Alelos , Asma/metabolismo , Linhagem Celular , Mapeamento Cromossômico , Análise por Conglomerados , Biologia Computacional/métodos , Expressão Gênica , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Polimorfismo de Nucleotídeo Único , Receptores de Interleucina-6/metabolismo , Transdução de Sinais
14.
Int J Colorectal Dis ; 31(2): 351-7, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26547863

RESUMO

INTRODUCTION: The success of sacral nerve stimulation, a common treatment for pelvic floor disorders, depends on correct placement of the electrodes through the sacral foramina. When the bony anatomy and topography of the sacrum and sacral spinal nerves are intact, this is easily achieved; where sacral anomalies exist, it can be challenging. A better understanding of common sacral malformations can improve the success of sacral nerve stimulation (SNS) electrode placement. MATERIAL AND METHODS: We reviewed 998 consecutive MRI scans performed to investigate low back pain in patients who had undergone CT and/or X-ray. RESULTS: Congenital sacral malformations were found in 24.1%, the most common being sacral meningeal cysts (16%) and spina bifida occulta (9.9%). Others were lumbosacral transitional vertebrae (2.5%), anterior occult meningocele (0.5%), partial sacral agenesis (0.2%) and vertebral dysplasia of S1 (0.2%). CONCLUSION: This radiologic review uncovered a high incidence of sacral malformations, and most were asymptomatic. All surgeons who perform SNS should have a basic understanding of sacral malformations, their incidence and effect on foraminal anatomy. Imaging will aid procedural planning.


Assuntos
Terapia por Estimulação Elétrica/métodos , Sacro/anormalidades , Sacro/inervação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Doenças Assintomáticas , Eletrodos , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Sacro/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Adulto Jovem
15.
J Dairy Sci ; 99(11): 8589-8597, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27544854

RESUMO

The objectives of this study were to characterize Staphylococcus aureus isolated from artisanal and industrialized Minas frescal cheeses, to determine their antimicrobial susceptibility profile as well as the genetic similarity among the isolates. The isolates were also tested for staphylococcal enterotoxin genes and other virulence factors. Fifty-six artisanal raw milk cheeses sold at street fairs and 10 industrialized cheeses commercialized in supermarkets of Goiânia, Goiás, were analyzed. Staphylococcus aureus was confirmed in 19 samples (33.9%) of artisanal cheese by detection of femA gene, in which 29 isolates were obtained. These isolates were submitted to the antimicrobial susceptibility test and classified into 9 different profiles (A-I). Thirteen isolates (44.8) were resistant to penicillin and 3 (10.3) to tetracycline, with 2 (7.4) resistant to both. The multiplex PCR technique was performed to detect virulence genes that code for the production of hemolysins (Hla and Hlb), toxic shock syndrome toxin (TSST-1), exfoliative toxins (ETa and ETb), and staphylococcal enterotoxins [SE; SEA-SEE, SEG-SEJ, SEM-SEO]. All the isolates amplified for the hla gene and 14 (48.3%) for the hlb gene. The seh gene was the most frequently detected (n=11, 37.9%), followed by seo gene (n=3; 10.3%). In one isolate (3.4%), 4 enterotoxins genes were detected, and in another, 6 (3.4%) were detected. The comparison performed by pulsed-field gel electrophoresis of the 29 isolates revealed 18 genotypic profiles, which were grouped into 5 clusters. The genotyping found high genetic similarity among the isolates. Identical isolates were obtained from different samples and one sample showed more than one genetically different isolate. The high prevalence of S. aureus in the Minas Frescal cheese samples, as well as the detection of toxin encoding genes identified in this study, warns of the necessity to reduce the contamination levels in this type of cheese through monitoring and controlling the production and trade of the product.


Assuntos
Queijo , Staphylococcus aureus , Animais , Enterotoxinas/genética , Contaminação de Alimentos , Microbiologia de Alimentos , Genótipo , Leite/química , Reação em Cadeia da Polimerase , Staphylococcus aureus/genética , Staphylococcus aureus/crescimento & desenvolvimento , Staphylococcus aureus/patogenicidade , Virulência
16.
Tech Coloproctol ; 20(12): 859-864, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27844258

RESUMO

BACKGROUND: Sacral nerve stimulation is a common treatment for various pelvic floor disorders. It consists of the percutaneous introduction of electrodes through the posterior sacral foramina for therapeutic stimulation of the target sacral spinal nerve. The aim of our study was to determine the surface anatomical landmarks of the sacrum to facilitate identification of the posterior sacral foramina. METHODS: This study was conducted on 20 human cadavers. The cadavers were placed in a prone position, and all the soft tissues of the sacral region were removed to allow exposure of the osseous structures. Different measurements were taken in relation to the posterior sacral foramina, the posterior superior iliac spine (PSIS) and the median sacral crest (MSC). A median coefficient of variation (CV) was determined. RESULTS: The diameter of the second sacral foramen showed the greatest variability. The distances between each individual foramen and the MSC had an acceptable variability (CV < 20%). In contrast, the distance between foramina had a high variability. The distance between PSIS and the second posterior sacral foramen was also found to have an acceptable variability (CV < 20%). However, the angle formed by an horizontal line between PSIS and a line between PSIS and S2 foramina had high variability. CONCLUSIONS: We found that the distance between sacral foramina and MSC is relatively constant while the distance between foramina and the relations between foramina and PSIS is highly variable. Detailed knowledge of the anatomy may facilitate electrode placement and is complementary to the regular use of fluoroscopy.


Assuntos
Pontos de Referência Anatômicos , Terapia por Estimulação Elétrica/métodos , Ílio/anatomia & histologia , Região Sacrococcígea/anatomia & histologia , Cadáver , Feminino , Humanos , Ílio/inervação , Masculino , Decúbito Ventral , Região Sacrococcígea/inervação
17.
Hum Genet ; 134(10): 1079-87, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26220684

RESUMO

Migraine has been defined as a common disabling primary headache disorder. Epidemiology studies have provided with the undeniable evidence of genetic components as active players in the development of the disease under a polygenic model in which multiple risk alleles exert modest individual effects. Our objective was to test the contribution of a polygenic effect to migraine risk in the Norfolk Island population using a panel of SNPs reported to be disease associated in published migraine GWAS. We also investigated whether individual SNPs were associated with gene expression levels measured in whole blood. Polygenic scores were calculated in a total of 285 related individuals (74 cases, 211 controls) from the Norfolk Island using 51 SNPs previously reported to be associated with migraine in published GWAS. The association between polygenic score and migraine case-control status was tested using logistic regression. Results indicate that a migraine polygenic risk score was associated with migraine case-control status in this population (P = 0.016). This supports the hypothesis that multiple SNPs with weak effects collectively contribute to migraine risk in this population. Amongst the SNPs included in the polygenic model, four were associated with the expression of the USMG5 gene, including rs171251 (P = 0.012). Results from this study provide evidence for a polygenic contribution to migraine risk in an isolated population and highlight specific SNPs that regulate the expression of USMG5, a gene critical for mitochondrial function.


Assuntos
Transtornos de Enxaqueca/genética , Herança Multifatorial , Polimorfismo de Nucleotídeo Único , Estudos de Casos e Controles , Feminino , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Masculino , Melanesia , Locos de Características Quantitativas
18.
J Theor Biol ; 367: 286-295, 2015 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-25484005

RESUMO

Turing's diffusion-driven instability for the standard two species reaction-diffusion system is only achievable under well-known and rather restrictive conditions on both the diffusion rates and the kinetic parameters, which necessitates the pairing of a self-activator with a self-inhibitor. In this study we generalize the standard two-species model by considering the case where the reactants can bind to an immobile substrate, for instance extra-cellular matrix, and investigate the influence of this dynamics on Turing's diffusion-driven instability. Such systems have been previously studied on the grounds that binding of the self-activator to a substrate may effectively reduce its diffusion rate and thus induce a Turing instability for species with equal diffusion coefficients, as originally demonstrated by Lengyel and Epstein (1992) under the assumption that the bound state dynamics occurs on a fast timescale. We, however, analyse the full system without any separation of timescales and demonstrate that the full system also allows a relaxation of the standard constraints on the reaction kinetics for the Turing instability, increasing the type of interactions that could give rise to spatial patterning. In particular, we show that two self-activators can undertake a diffusively driven instability in the presence of a binding immobile substrate, highlighting that the interactions required of a putative biological Turing instability need not be associated with a self-activator-self-inhibitor morphogen pair.


Assuntos
Modelos Biológicos , Difusão , Cinética , Análise Numérica Assistida por Computador , Especificidade por Substrato
19.
J Dairy Sci ; 97(9): 5521-32, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24952785

RESUMO

The objectives of the current experiment were to determine the effects of 2 prepartum stocking densities on milk yield, concentration of metabolites during the peripartum period, and health and reproductive parameters of dairy cows. Jersey cows enrolled in the experiment at 254±3 d of gestation were balanced for parity (nulliparous vs. parous) and previous lactation projected 305-d mature equivalent milk yield (parous) and assigned to 1 of 2 treatments: 80% headlock stocking density (80SD; 38 animals/48 headlocks) and 100% headlock stocking density (100SD; 48 animals/48 headlocks). The number of experimental units was 8 (4 replicates and 2 pens/treatment per replicate). In total, 154 nulliparous and 184 parous animals were enrolled in the 80SD treatment and 186 nulliparous and 232 parous animals were enrolled in the 100SD treatment. At the start of each replicate, treatments were switched within pen. Cows were milked thrice daily and monthly milk yield, fat and protein content, and somatic cell count data were recorded up to 155 d postpartum. Plasma nonesterified fatty acid concentration was measured weekly, from -18±3 to 17±3 d relative to calving, and plasma ß-hydroxybutyrate was measured weekly, from 1±2 to 17±3 d relative to calving. Cows were examined 1, 4±1, 7±1, 10±1, and 13±1 d relative to calving for diagnosis of uterine diseases. Blood was sampled for determination of progesterone concentration and resumption of ovarian cycles 35±3 and 45±3 d relative to calving. Average headlock (74.1±0.4 vs. 94.5±0.3%) and stall (80.8±0.4 vs. 103.1±0.4%) stocking density was lower for the 80SD treatment compared with the 100SD treatment. Treatment did not affect incidence of retained fetal membranes (80SD=5.1, 100SD=7.8%), metritis (80SD=21.2, 100SD=16.7%), acute metritis (80SD=9.9, 100SD=9.4%), and vaginal purulent discharge (80SD=5.8, 100SD=7.9%). Concentrations of nonesterified fatty acids (80SD=251.5±6.1, 100SD=245.9±5.6µmol/L) and ß-hydroxybutyrate (80SD=508.2±14.3, 100SD=490.9±13.6µmol/L) were not different between treatments. Treatment had no effect on percentage of cows removed from the herd on the first 60 d postpartum (80SD=6.1, 100SD=5.1%) and on rate of removal from the herd up to 305 d postpartum 80SD=referent, 100SD [adjusted hazard ratio (95% confidence interval)]=1.02 (0.75, 1.38). Percentages of cows pregnant to first (80SD=41.9, 100SD=48.4%) and second (80SD=49.3, 100SD=42.0%) postpartum AI were not different between treatments. Finally, treatment did not affect energy-corrected milk yield up to 155 d postpartum (80SD=33.8±0.5, 100SD=33.4±0.5kg/d). In herds with weekly or twice weekly movement of new cows to the prepartum pen and separate housing of nulliparous and parous animals, a target stocking density of 100% of headlocks on the day of movement is not expected to affect health, metabolic, reproductive, and productive parameters.


Assuntos
Doenças dos Bovinos/epidemiologia , Bovinos/fisiologia , Endometrite/veterinária , Leite/metabolismo , Placenta Retida/veterinária , Reprodução , Ácido 3-Hidroxibutírico/sangue , Animais , Comportamento Animal , Contagem de Células , Endometrite/epidemiologia , Ácidos Graxos não Esterificados/sangue , Feminino , Incidência , Lactação , Modelos Logísticos , Paridade , Período Periparto , Placenta Retida/epidemiologia , Densidade Demográfica , Período Pós-Parto , Gravidez , Progesterona/sangue
20.
Mycologia ; 116(1): 184-212, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38127644

RESUMO

The genus Ceratocystis contains a number of emerging plant pathogens, mostly members of the Latin American Clade (LAC), in which there are several unresolved taxonomic controversies. Among the most important are Brazilian pathogens in the C. fimbriata complex, C. manginecans and C. eucalypticola. Representatives of C. manginecans and C. eucalypticola from India and China, respectively, were shown to be fully interfertile in laboratory matings, and hybrids between the putative species were identified on Punica in India. An Indian tester strain was sexually compatible with representatives of what has been considered C. fimbriata on numerous hosts across Brazil. In this revision of the LAC, the name C. fimbriata is restricted to the widely dispersed Ipomoea strain, and C. manginecans is recognized as a Brazilian species that is important on Mangifera, Eucalyptus, and many other crops. C. mangivora and C. mangicola are also considered synonyms of C. manginecans. Based on phylogenetics and mating studies, two other Brazilian species are recognized: C. atlantica, sp. nov., and C. alfenasii, sp. nov., each with wide host ranges. Three new Caribbean species are recognized based on phylogenetics and earlier inoculation studies: C. costaricensis, sp. nov., on Coffea, C. cubensis, sp. nov., on Spathodea, and C. xanthosomatis, sp. nov., on the vegetatively propagated aroids Xanthosoma and Syngonium. Some of the other Ceratocystis species were based primarily on unique internal transcribed spacer (ITS) rDNA sequences, but the unreliability of rDNA sequences was demonstrated when intraspecific crossing of isolates with differing ITS sequences generated single-ascospore progeny with intragenomic variation in ITS sequences and others with new ITS sequences. Species recognition in Ceratocystis should use phenotype, including intersterility tests, to help identify which lineages are species. Although some species remain under-studied, we recognize 16 species in the LAC, all believed to be native to Latin America, the Caribbean region, or eastern USA.


Assuntos
Ascomicetos , Ceratocystis , Ceratocystis/genética , América Latina , DNA Espaçador Ribossômico/genética , DNA Fúngico/genética , Doenças das Plantas , DNA Ribossômico/genética
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