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1.
J Clin Periodontol ; 50(9): 1176-1187, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37246304

RESUMO

AIM: To investigate the differences between the subgingival microbiota of healthy subjects (HS) and periodontitis patients (PP) from four different countries through a metagenomic approach. MATERIALS AND METHODS: Subgingival samples were obtained from subjects from four different countries. Microbial composition was analysed through high-throughput sequencing of the V3-V4 region of the 16S rRNA gene. The country of origin, diagnosis and clinical and demographic variables of the subjects were used to analyse the microbial profiles. RESULTS: In total, 506 subgingival samples were analysed: 196 from HS and 310 from patients with periodontitis. Differences in richness, diversity and microbial composition were observed when comparing samples pertaining to different countries of origin and different subject diagnoses. Clinical variables, such as bleeding on probing, did not significantly affect the bacterial composition of the samples. A highly conserved core of microbiota associated with periodontitis was detected, while the microbiota associated with periodontally HS was much more diverse. CONCLUSIONS: Periodontal diagnosis of the subjects was the main variable explaining the composition of the microbiota in the subgingival niche. Nevertheless, the country of origin also had a significant impact on the microbiota and is therefore an important factor to consider when describing subgingival bacterial communities.


Assuntos
Placa Dentária , Microbiota , Periodontite , Humanos , RNA Ribossômico 16S/genética , Genes de RNAr , Voluntários Saudáveis , Placa Dentária/microbiologia , Periodontite/microbiologia , Bactérias/genética , Microbiota/genética
2.
Proc Natl Acad Sci U S A ; 117(28): 16226-16233, 2020 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-32601231

RESUMO

Competing interactions in quantum materials induce exotic states of matter such as frustrated magnets, an extensive field of research from both the theoretical and experimental perspectives. Here, we show that competing energy scales present in the low-dimensional orbital-selective Mott phase (OSMP) induce an exotic magnetic order, never reported before. Earlier neutron-scattering experiments on iron-based 123 ladder materials, where OSMP is relevant, already confirmed our previous theoretical prediction of block magnetism (magnetic order of the form [Formula: see text]). Now we argue that another phase can be stabilized in multiorbital Hubbard models, the block-spiral state. In this state, the magnetic islands form a spiral propagating through the chain but with the blocks maintaining their identity, namely rigidly rotating. The block-spiral state is stabilized without any apparent frustration, the common avenue to generate spiral arrangements in multiferroics. By examining the behavior of the electronic degrees of freedom, parity-breaking quasiparticles are revealed. Finally, a simple phenomenological model that accurately captures the macroscopic spin spiral arrangement is also introduced, and fingerprints for the neutron-scattering experimental detection are provided.

3.
Med Oral Patol Oral Cir Bucal ; 28(6): e630-e637, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37622430

RESUMO

BACKGROUND: in Colombia, oral cancer is the eighth most common type of cancer, with an estimated survival rate of 52%. Lack of knowledge about oral cancer and its risk factors is associated with late detection. MATERIAL AND METHODS: a descriptive cross-sectional study was carried out on 268 patients attending the School of Dentistry of the University of Antioquia clinics, to whom a validated 47-question questionnaire was applied by phone during the COVID-19 pandemic (2020 and 2021). Data were analyzed using the SPSS software. RESULTS: the mean age was 58.9. 58.6% of the participants had heard of oral cancer, 42% acquire knowledge from the media, and 96.7% considered screening necessary. Most of the patients expressed not feeling worried (54.5%), fearful (59.7%), or anxious (56.3%) in the case of being submitted to an examination for early detection of oral cancer. A correlation between low socioeconomic status and educational level with less knowledge of oral cancer was found. The dimensions of experience and attitude towards screening were not associated with sociodemographic variables. CONCLUSIONS: There is little knowledge about oral cancer, especially in low socioeconomic and educational status, although this does not occur in the dimensions of attitude and experience toward screening. In contrast, patients participating in this study presented high knowledge about oral cancer risk. This population recognizes the situations most related to the development of cancer. This level of knowledge was similar for the demographic conditions except for people with no education, who presented less knowledge of the risks. The need for educational campaigns on oral cancer knowledge is reaffirmed, especially in socially disadvantaged groups, considering that there would be no barriers related to screening.


Assuntos
COVID-19 , Neoplasias Bucais , Humanos , Adulto , Pessoa de Meia-Idade , RNA Viral , Estudos Transversais , Colômbia , Pandemias , Conhecimentos, Atitudes e Prática em Saúde , COVID-19/epidemiologia , SARS-CoV-2 , Neoplasias Bucais/diagnóstico , Neoplasias Bucais/epidemiologia , Inquéritos e Questionários
4.
Rep Prog Phys ; 85(2)2022 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-34942603

RESUMO

In this paper, we describe the potential of the LHCb experiment to detect stealth physics. This refers to dynamics beyond the standard model that would elude searches that focus on energetic objects or precision measurements of known processes. Stealth signatures include long-lived particles and light resonances that are produced very rarely or together with overwhelming backgrounds. We will discuss why LHCb is equipped to discover this kind of physics at the Large Hadron Collider and provide examples of well-motivated theoretical models that can be probed with great detail at the experiment.

5.
BMC Public Health ; 21(1): 964, 2021 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-34020616

RESUMO

BACKGROUND: Prevention of TB is paramount to achieving elimination targets as recommended by the World Health Organization's action framework for low incidence countries striving to eliminate TB. Although the rates of TB in Canada are low, understanding the latent TB infection (LTBI) cascade is paramount to identifying gaps in care and treatment barriers, thereby increasing the effectiveness of preventive strategies. The purpose of this study was to examine the LTBI cascade of care and identify barriers to treatment completion in adults referred from primary care to a regional tertiary care TB clinic in Ottawa, Canada. METHODS: Electronic medical records between January 2010 and December 2016 were reviewed retrospectively and an LTBI cascade of care was constructed from The Ottawa Hospital TB clinic and surrounding primary care clinics. A cohort of 2207 patients with untreated LTBI was used to ascertain the associations between demographic and clinical factors for both treatment non-initiation and non-completion using log-binomial univariable and multivariable regression models. RESULTS: Of 2207 patients with untreated LTBI who were seen in the clinic during the study period, 1771 (80.2%) were offered treatment, 1203 (67.9% of those offered) started treatment, and 795 (66.1% of those started) completed treatment. In multivariable analysis, non-initiation of treatment was associated with older age (adjusted risk ratio [aRR] 1.06 per 5-year increase, 95% CI: 1.03-1.08) and female gender (aRR 1.28, 95% CI: 1.11-1.47). Non completion of treatment was associated with referral from the TB Clinic back to the primary care team following initial consult (aRR 1.62, 95% CI: 1.35-1.94) and treatment with the standard of 9 months of Isoniazid (9H) compared to 4 months of Rifampin (4R) (aRR 1.45, 95% CI:1.20-1.74). CONCLUSIONS: LTBI treatment completion was significantly decreased among patients who were referred back to primary care from the TB clinic. The 4R regimen resulted in more people completing LTBI treatment compared to 9H in keeping with a recently published RCT. Improved education, communication, and collaboration between tertiary care TB clinics and primary care teams may improve treatment completion rates and address the TB burden in low incidence communities in Canada.


Assuntos
Tuberculose Latente , Adulto , Idoso , Antituberculosos/uso terapêutico , Canadá/epidemiologia , Feminino , Humanos , Incidência , Isoniazida , Tuberculose Latente/tratamento farmacológico , Tuberculose Latente/epidemiologia , Estudos Retrospectivos
6.
Med Oral Patol Oral Cir Bucal ; 26(5): e602-e610, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-33772566

RESUMO

BACKGROUND: Peri-implant mucositis and peri-implantitis are the main biological complications associated with dental implants. Since most authors agree that bacteria play a major etiological role, the main aims of this study were to determine if a formulation of erythritol and chlorhexidine applied with an air polishing system inhibits biofilm regrowth over dental implants and to compare the decontamination capacity of this therapy with that of mechanical removal by saline and gauze. MATERIAL AND METHODS: A multispecies biofilm (P. gingivalis, A. actinomycetemcomitans, F. nucleatum, A. naeslundii, V. parvula and S. oralis) was grown for 14 days on 52 dental implants in an artificial mouth. These implants were divided into three groups according to the applied treatment: 14 negative control (CON), 19 erythritol-chlorhexidine (ERY) and 19 gauze with saline (GAU) samples. Twelve dental implants from the ERY and GAU groups and 8 implants from the CON group were re-incubated for 7 additional days after treatment. The bacterial count was performed by quantitative polymerase chain reaction (qPCR) using propidium monoazide (PMA). A descriptive and bivariate analysis of the data was performed. RESULTS: The erythritol and chlorhexidine formulation significantly inhibited biofilm regrowth in comparison with the mechanical treatment (GAU), since a significant decrease in all the species was observed in the ERY group (except for Aggregatibacter actinomycetemcomitans). The antibiofilm and antibacterial capacity of the two active treatment groups (ERY and GAU) was similar for a 14 days multispecies in vitro biofilm, except for the lower count of A. naeslundii in the GAU group. CONCLUSIONS: The use of erythritol powder with chlorhexidine applied with an air polishing system reduces biofilm regrowth over dental implants when compared with mechanical removal by saline and gauze. This effect might be beneficial for patients included in peri-implant maintenance programs.


Assuntos
Implantes Dentários , Peri-Implantite , Biofilmes , Eritritol , Humanos , Pós
7.
Phys Rev Lett ; 123(2): 027203, 2019 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-31386537

RESUMO

Inelastic neutron scattering recently confirmed the theoretical prediction of a ↑↑↓↓-magnetic state along the legs of quasi-one-dimensional iron-based ladders in the orbital-selective Mott phase (OSMP). We show here that electron doping of the OSMP induces a whole class of novel block states with a variety of periodicities beyond the previously reported π/2 pattern. We discuss the magnetic phase diagram of the OSMP regime that could be tested by neutrons once appropriate quasi-1D quantum materials with the appropriate dopings are identified.

8.
Water Sci Technol ; 80(4): 675-684, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31661447

RESUMO

Microbial processes are critical to the function of freshwater ecosystems, yet we still do not fully understand the factors that shape freshwater microbial communities. Furthermore, freshwater ecosystems are particularly susceptible to effects of environmental change, including influx of exogenous nutrients such as nitrogen and phosphorus. To evaluate the impact of nitrogen loading on the microbial community structure of shallow freshwater lakes, water samples collected from Lake Shenandoah (Virginia, USA) were incubated with two concentrations of either ammonium, nitrate, or urea as a nitrogen source. The potential impact of these nitrogen compounds on the bacterial community structure was assessed via 16S rRNA amplicon sequencing. At the phylum level, the dominant taxa in Lake Shenandoah were comprised of Actinobacteria and Proteobacteria, which were not affected by exposure to the various nitrogen treatments. Overall, there was not a significant shift in the diversity of the bacterial community of Lake Shenandoah with the addition of nitrogen sources, indicating this shallow system may be constrained by other environmental factors.


Assuntos
Lagos , Nitrogênio , Bactérias , Proteobactérias , RNA Ribossômico 16S
9.
Psychol Med ; 47(3): 484-494, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27776562

RESUMO

BACKGROUND: Laboratory tasks to delineate anxiety disorder features are used to refine classification and inform our understanding of etiological mechanisms. The present study examines laboratory measures of response inhibition, specifically the inhibition of a pre-potent motor response, in clinical anxiety. Data on associations between anxiety and response inhibition remain inconsistent, perhaps because of dissociable effects of clinical anxiety and experimentally manipulated state anxiety. Few studies directly assess the independent and interacting effects of these two anxiety types (state v. disorder) on response inhibition. The current study accomplished this goal, by manipulating state anxiety in healthy and clinically anxious individuals while they complete a response inhibition task. METHOD: The study employs the threat-of-shock paradigm, one of the best-established manipulations for robustly increasing state anxiety. Participants included 82 adults (41 healthy; 41 patients with an anxiety disorder). A go/nogo task with highly frequent go trials was administered during alternating periods of safety and shock threat. Signal detection theory was used to quantify response bias and signal-detection sensitivity. RESULTS: There were independent effects of anxiety and clinical anxiety on response inhibition. In both groups, heightened anxiety facilitated response inhibition, leading to reduced nogo commission errors. Compared with the healthy group, clinical anxiety was associated with excessive response inhibition and increased go omission errors in both the safe and threat conditions. CONCLUSIONS: Response inhibition and its impact on go omission errors appear to be a promising behavioral marker of clinical anxiety. These results have implications for a dimensional view of clinical anxiety.


Assuntos
Transtornos de Ansiedade/fisiopatologia , Medo/fisiologia , Inibição Psicológica , Desempenho Psicomotor/fisiologia , Detecção de Sinal Psicológico/fisiologia , Adulto , Biomarcadores , Feminino , Humanos , Masculino , Adulto Jovem
10.
Reprod Domest Anim ; 52(5): 775-780, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28432708

RESUMO

The objectives of this study were to evaluate if vitrified porcine spermatozoa are able to maintain their capacity to produce zygotes in vitro using intracytoplasmic sperm injection (ICSI) and to evaluate the zygote development in two in vitro atmospheric conditions: 5% CO2 and tri-gas. A group of porcine oocytes maturated in vitro were injected with vitrified-warmed sperm (treatment group) and another group, with sperm diluted and conserved at 17°C (control group). To evidence parthenogenetic activation, some oocytes were submitted to a Sham test. The injected oocytes were cultured in G1 medium at 38°C, 100% humidity and 5% CO2 or tri-gas. No significant differences (p > .05) were observed in embryo development between the oocytes injected with vitrified-warmed sperm (31.8%; 36/113), and those injected with semen diluted and conserved at 17°C (35.5%; 32/90), when cultured in 5% CO2 or under tri-gas atmosphere (42.9%; 39/91 vs. 34.2%; 26/76, respectively). No significant differences (p > .05) were observed in the percentage of pronuclei (PN) obtained between 5% CO2 and tri-gas, within each treatment either. Of the 52 oocytes submitted to the Sham test, only two presented a female PN (activation) indicating that the PN observed in the treatment group were a product of fertilization and not parthenogenetic activation. To conclude, porcine sperm vitrified using spheres, at a concentration of 5 × 106  spermatozoa/ml in TALP medium with 1% bovine serum albumin (BSA), conserve condensed and intact chromatin capable of producing early embryo development up to the pronuclear stage.


Assuntos
Injeções de Esperma Intracitoplásmicas/veterinária , Sus scrofa/fisiologia , Vitrificação , Animais , Criopreservação/métodos , Técnicas de Cultura Embrionária/veterinária , Desenvolvimento Embrionário/fisiologia , Feminino , Fertilização in vitro/veterinária , Gases , Masculino , Oócitos , Espermatozoides , Zigoto/crescimento & desenvolvimento
11.
Biochim Biophys Acta ; 1838(3): 950-6, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24192054

RESUMO

The aim of this study is to calculate the membrane elastic energy for the different shapes observed in the discocyte-stomatocyte sequence. This analysis can provide a better quantitative understanding of the hypothesis put forward over the last decades to explain how red blood cells produce and maintain their typical shape. For this purpose, we use geometrical models based on parametric equations. The energy model considered for the elastic properties of RBC membrane includes the local and nonlocal resistance effects of the bilayer to bending. In particular, the results confirm the discocyte as the lowest energy value configuration among the sets of different red blood cell deformations considered in the sequence.


Assuntos
Elasticidade , Deformação Eritrocítica/fisiologia , Membrana Eritrocítica/química , Eritrócitos/química , Bicamadas Lipídicas/química , Humanos , Modelos Teóricos
12.
Phys Rev Lett ; 114(6): 066401, 2015 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-25723231

RESUMO

Using the time-dependent density-matrix renormalization group (tDMRG), we study the time evolution of electron wave packets in one-dimensional (1D) metal-superconductor heterostructures. The results show Andreev reflection at the interface, as expected. By combining these results with the well-known single-spin-species electron-hole transformation in the Hubbard model, we predict an analogous spin Andreev reflection in metal-Mott insulator heterostructures. This effect is numerically confirmed using 1D tDMRG, but it is expected to also be present in higher dimensions, as well as in more general Hamiltonians. We present an intuitive picture of the spin reflection, analogous to that of Andreev reflection at metal-superconductor interfaces. This allows us to discuss a novel antiferromagnetic proximity effect. Possible experimental realizations are discussed.

13.
Reprod Domest Anim ; 50(2): 200-205, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25522082

RESUMO

The aim of this study was to examine the effect of varying intracellular reactive oxygen species (ROS) levels during oocyte in vitro maturation with enzymatic ROS production systems (xanthine + xanthine oxidase or xanthine + xanthine oxidase + catalase), scavenger systems (catalase or superoxide dismutase + catalase) or cysteine on porcine oocyte maturation. Oocyte ROS levels showed an increase when H2O2 or O2∙(-) production systems were added to the culture medium (p < 0.05). On the other hand, the presence of ROS scavengers in the maturation medium did not modify oocyte ROS levels compared with the control after 48 h of maturation, but the addition of cysteine induced a decrease in oocyte ROS levels (p < 0.05). The ROS production systems used in this work did not modified the percentage of oocyte nuclear maturation, but increased the decondensation of sperm head (p < 0.05) and decreased the pronuclear formation (p < 0.05). In turn, the addition of O2∙(-) and H2O2 scavenging systems during in vitro maturation did not modify the percentage of oocytes reaching metaphase II nor the oocytes with decondensed sperm head or pronuclei after fertilization. However, both parameters increased in the presence of cysteine (p < 0.05). The exogenous generation of O2∙(-) and H2O2 during oocyte in vitro maturation would not affect nuclear maturation or later sperm penetration, but most of the spermatozoa cannot progress to form the pronuclei after fusion with the oocyte. The decrease in endogenous ROS levels by the addition of cysteine would improve pronuclear formation after sperm penetration.


Assuntos
Técnicas de Maturação in Vitro de Oócitos/veterinária , Oócitos/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Suínos , Animais , Meios de Cultura , Oxigênio/farmacologia
14.
Curr Oncol ; 22(4): 246-51, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26300662

RESUMO

BACKGROUND: Cancer is a health concern in Inuit populations. Unique cultural, dietary, and genetic factors and geographic isolation influence cancer epidemiology in this group. Inuit-specific data about oncology treatments and survival outcomes in Canadian Inuit referred to urban treatment centres are lacking. METHODS: A retrospective chart review of Inuit patients referred to The Ottawa Hospital Cancer Centre (tohcc) from the Baffin region of Nunavut between 2000 and 2010 was conducted. Nunavut cancer registry data were used to establish the percentage of cancer cases referred and their survival outcomes. RESULTS: Of 307 cancer patients registered among Baffin-region Inuit, 216 [70% (63 men, 153 women)] were referred to tohcc for chemotherapy (ct) and radiation therapy (rt). Mean age in the referred group was 59.3 years (range: 25-89 years), and current smokers constituted half the group (52%). The cancers most commonly leading to referral in men were lung (55%), colorectal (19%), and nasopharyngeal (11%) cancers; in women, they were lung (46%), colorectal (24%), breast (10%), nasopharyngeal (6%), and cervical (5%) cancers. Of the 216 referred patients, 82 (38%) had already undergone surgery, and 18 (8%) received chemoradiation or rt only, all given with curative intent. Among the surgical patients referred, 33 (40%) and 23 (28%) went on to receive adjuvant ct and adjuvant rt respectively. Among 116 patients referred for palliative care, 64 (55%) received ct, 76 (66%) received rt, 43 (37%) received both ct and rt, and 19 (16%) received neither treatment. Median all-stage overall survival was 10 months for patients with lung cancer [95% confidence interval: 6.1 to 13.9 months] and 37 months for patients with colorectal cancer [95% confidence interval: 14.8 to 59.2 months]. CONCLUSIONS: High uptake of palliative and adjuvant ct and rt was observed in the Inuit patients referred to tohcc. Lung cancer was the most common cancer in referred Inuit men and women. The survival rates for Inuit lung cancer patients referred to tohcc were comparable to those in the rest of Canada. Further research is required to understand reasons for non-referral of Canadian Inuit to tohcc.

15.
Rev Gastroenterol Mex ; 80(4): 239-47, 2015.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-26253888

RESUMO

BACKGROUND: Identifying persons at high risk for advanced colorectal neoplasia can aid in the prevention of colon cancer. Previous studies have shown that some patients can present with proximal advanced neoplasia with no distal findings. AIMS: To determine the factors related to advanced neoplasia and advanced proximal colorectal neoplasia in a Latin American population. MATERIAL AND METHODS: A prospective, cross-sectional, observational, analytic study was conducted. It included patients that underwent colonoscopy at the Policlínico Peruano Japonés within the time frame of January and July 2012. Advanced neoplasia was defined as the presence of lesions ≥ 10mm with a villous component, high-grade dysplasia, or carcinoma. The splenic flexure was the limit between the proximal and distal colon. RESULTS: A total of 846 patients were included in the study. Advanced neoplasia was detected in 108 patients (12.8%) and advanced proximal neoplasia in 55 patients (6.7%), 42 (76.4%) of whom had no neoplasia in the distal colon. Factors related to advanced neoplasia found in the multivariate analysis were age, at the intervals of 50-59 (p=0.019), 60-69 (p=0.016), and ≥ 70 years (0.002) and male sex (p=0.003). In the evaluation of advanced proximal neoplasia, the multivariate analysis identified the 60-69 year age interval (p=0.039) and advanced distal neoplasia (p=0.028) as factors related to advanced proximal disease. The ROC curve established the age cut-off point at 60 years for initially performing colonoscopy, rather than sigmoidoscopy. CONCLUSIONS: Age and sex are related to advanced neoplasia, whereas age and advanced distal neoplasia are related to advanced proximal neoplasia.


Assuntos
Adenoma/patologia , Colo/patologia , Neoplasias Colorretais/patologia , Adenoma/diagnóstico por imagem , Adenoma/etiologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Colonoscopia , Neoplasias Colorretais/diagnóstico por imagem , Neoplasias Colorretais/etiologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estadiamento de Neoplasias , Peru , Estudos Prospectivos , Fatores de Risco , Fatores Sexuais
16.
Avian Dis ; 58(4): 638-41, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25619011

RESUMO

Actinobacillus pleuropneumoniae is the causal agent of porcine pleuropneumonia, which is a highly contagious respiratory disease that affects swine nearly exclusively. An isolate with characteristics of some Pasteurellaceae family members (Gram-negative bacterium, pleomorphic, and NAD-dependent) was isolated from layer hens showing clinical signs of infectious coryza. This bacterium presented hemolysis on rabbit red blood cell agar plates, and PCR amplification and sequencing of its 16S rDNA gene indicated 99% identity with A. pleuropneumoniae serotypes 3 and 7. The presence of a putative apxIIA gene was also determined by PCR. A single, smooth colony of this bacterium inoculated in five, 7-day-old chicken embryos via the yolk sac route induced 100% mortality. However, inoculation into 10-wk-old, specific-pathogen-free chickens induced only light facial swelling, and reisolation of the inoculated bacterium was negative.


Assuntos
Infecções por Actinobacillus/veterinária , Actinobacillus pleuropneumoniae/isolamento & purificação , Galinhas , Doenças das Aves Domésticas/microbiologia , Infecções por Actinobacillus/microbiologia , Actinobacillus pleuropneumoniae/genética , Animais , Feminino , Filogenia , Organismos Livres de Patógenos Específicos
17.
Reprod Domest Anim ; 49(6): 1068-73, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25307885

RESUMO

Oocyte maturation depends on the metabolic activity of cumulus-oocyte complex (COC) that performs nutritive and regulatory functions during this process. In this work, the enzymes [phosphofructokinase (PFK) and malate dehydrogenase (MDH)] were tested to elucidate the metabolic profile of porcine COCs during the in vitro maturation (IVM). Enzymatic activity was expressed in U/COC and U/mg protein (specific activity) as mean ± SEM. In vitro maturation was performed with 2-oxoglutarate (5, 10 and 20 mm) or hydroxymalonate (30, 60 and 100 mm) inhibitors of PFK and MDH, respectively. The PFK and MDH activities (U) remained constant during maturation. For PFK, the U were (2.48 ± 0.23) 10(-5) and (2.54 ± 0.32) 10(-5) , and for MDH, the U were (4.72 ± 0.42) 10(-5) and (4.38 ± 0.25) 10(-5) for immature and in vitro matured COCs, respectively. The specific activities were significantly lower after IVM, for PFK (4.29 ± 0.48) 10(-3) and (0.94 ± 0.12) 10(-3) , and for MDH (9.08 ± 0.93) 10(-3) and (1.89 ± 0.10) 10(-3) for immature and in vitro matured COCs, respectively. In vitro maturation percentages and enzymatic activity diminished with 20 mm 2-oxoglutarate or 60 mm hydroxymalonate (p < 0.05). Viability was not affected by any concentration of the inhibitors evaluated. The U remained unchanged during IVM; however, the increase in the total protein content per COC provoked a decrease in the specific activity of both enzymes. Phosphofructokinase and MDH necessary for oocyte IVM would be already present in the immature oocyte. The presence of inhibitors of these enzymes impairs the meiotic maturation. Therefore, the participation of these enzymes in the energy metabolism of the porcine oocyte during IVM is confirmed in this study.


Assuntos
Técnicas de Maturação in Vitro de Oócitos/veterinária , Malato Desidrogenase/metabolismo , Oócitos/enzimologia , Fosfofrutoquinases/metabolismo , Suínos/fisiologia , Animais , Sobrevivência Celular , Células do Cúmulo , Regulação Enzimológica da Expressão Gênica/fisiologia , Ácidos Cetoglutáricos/farmacologia , Malato Desidrogenase/antagonistas & inibidores , Malato Desidrogenase/genética , Meiose/fisiologia , Fosfofrutoquinases/antagonistas & inibidores , Fosfofrutoquinases/genética , Tartronatos/farmacologia
18.
Heredity (Edinb) ; 111(2): 114-21, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23572123

RESUMO

The European royal dynasties of the Early Modern Age provide a useful framework for human inbreeding research. In this article, consanguineous marriage, inbreeding depression and the purging of deleterious alleles within a consanguineous population are investigated in the Habsburgs, a royal dynasty with a long history of consanguinity over generations. Genealogical information from a number of historical sources was used to compute kinship and inbreeding coefficients for the Habsburgs. The marriages contracted by the Habsburgs from 1450 to 1750 presented an extremely high mean kinship (0.0628±0.009), which was the result of the matrimonial policy conducted by the dynasty to establish political alliances through marriage. A strong inbreeding depression for both infant and child survival was detected in the progeny of 71 Habsburg marriages in the period 1450-1800. The inbreeding load for child survival experienced a pronounced decrease from 3.98±0.87 in the period 1450-1600 to 0.93±0.62 in the period 1600-1800, but temporal changes in the inbreeding depression for infant survival were not detected. Such a reduction of inbreeding depression for child survival in a relatively small number of generations could be caused by elimination of deleterious alleles of a large effect according with predictions from purging models. The differential purging of the infant and child inbreeding loads suggest that the genetic basis of inbreeding depression was probably very different for infant and child survival in the Habsburg lineage. Our findings provide empirical support that human inbreeding depression for some fitness components might be purged by selection within consanguineous populations.


Assuntos
Mortalidade da Criança/história , Consanguinidade , Genealogia e Heráldica , Modelos Genéticos , Adulto , Alelos , Criança , Europa (Continente) , Feminino , História do Século XV , História do Século XVI , História do Século XVII , História do Século XVIII , Humanos , Lactente , Masculino , Linhagem , Seleção Genética
19.
Lupus ; 22(11): 1128-34, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23989736

RESUMO

The objective of this study was to assess the effects of rituximab on bone mineral density (BMD) in women with systemic lupus erythematosus (SLE) 1 year after treatment. Thirty active female SLE patients treated with rituximab were compared with 43 SLE women not treated with rituximab. BMD was measured using dual energy X-ray absorptiometry (DEXA) before initiating biologic therapy and after 1 year. The mean age was 38.5 ± 2.1 years; median disease duration was 7 years. In the rituximab group, after 1 year of follow-up, BMD at the femoral neck (FN) decreased from 0.980 ± 0.130 g/cm(2) to 0.809 ± 0.139 g/cm(2) (-17.4%; p=0.001). Similarly, BMD at the lumbar spine (LS) decreased from 1.062 ± 0.137 g/cm(2) to 0.893 ± 0.194 g/cm(2) (-15.8%; p=0.001). In control subjects, BMD at the FN decreased from 0.914 ± 0.193 g/cm(2) to 0.890 ± 0.135 g/cm(2) (-2.6%; p=0.001), and BMD at the LS decreased from 0.926 ± 0.128 g/cm(2) to 0.867 ± 0.139 g/cm(2) (-6.2%; p=0.09). After 1 year, SLE patients had lower BMD at both the FN and LS, but the loss was greater in postmenopausal patients who had received rituximab therapy.


Assuntos
Anticorpos Monoclonais Murinos/uso terapêutico , Densidade Óssea/efeitos dos fármacos , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Adulto , Anticorpos Monoclonais Murinos/farmacologia , Linfócitos B/fisiologia , Feminino , Glucocorticoides/farmacologia , Humanos , Lúpus Eritematoso Sistêmico/metabolismo , Estudos Prospectivos , Rituximab , Fatores de Tempo
20.
Cryobiology ; 67(3): 391-3, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23988558

RESUMO

The purpose of this work was to assess commercially available Cryotech Vitrification Kit, in terms of survival, in vitro development and pregnancy rate for bovine embryos. Cumulus-oocyte complexes (COCs) were recovered from ovaries obtained from slaughtered cows and then matured in vitro for 22 h. COCs were fertilized by sex-sorted sperm in IVF-mSOF and cultured in IVC-mSOF for 7 days to the blastocyst stage. Blastocysts were vitrified with the Cryotech Vitrification Kit(®) and then either warmed to check viability or transferred to synchronized heifers. We observed 100% survival of the in vitro produced blastocysts and obtained the same pregnancy rate (46.8%) as that obtained using fresh in vitro produced blastocysts. We thus conclude that the Cryotech vitrification method is a valid alternative to other vitrification or slow-cooling methods in the bovine species and that it is ready for livestock production.


Assuntos
Blastocisto/citologia , Bovinos/embriologia , Criopreservação/veterinária , Vitrificação , Animais , Sobrevivência Celular , Criopreservação/métodos , Transferência Embrionária/veterinária , Feminino , Fertilização in vitro/veterinária , Gravidez
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