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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 318: 124498, 2024 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-38788509

RESUMO

The oxidative stability of biodiesel is defined by its relative resistance to the action of oxygen at room temperature. Its determination is an essential reference to the quality of biofuel and a significant parameter to be determined. This parameter concerns the quality of the biodiesel to be supplied to the consumer, and its determination is fundamental to maintaining the engine's proper functioning. Raman spectroscopy allows the rapid obtaining of structural information regarding biodiesel quality and, when aided by multivariate analysis methods, allows a quantitative determination of specific properties. This work uses Raman spectroscopy, Multivariate Curve Resolution with Alternative Least Squares (MCR-ALS) method, and Evolving Factor Analysis (EFA) to study biodiesel's oxidation kinetics. Also, the vibrational modes C = C, CH2, and CH3 were identified as the main structural groups involved in this process, corroborating previous studies. The MCR-ALS & EFA combination allowed modeling of the degradation kinetics following an A â†’ B â†’ C mechanism, where A corresponds to the biodiesel (starting material), B is related to the hydroperoxide mixture, and C is the final product. The results also suggested that this process follows a first-order reaction, with kinetic constant values of k1 = 0.0056 min-1 and k2 = 0.0031 min-1.

2.
Zygote ; 31(5): 468-474, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37366027

RESUMO

In the present study, the cryoprotective effects of Lolium perenne antifreeze protein (LpAFP) on the vitrification of bovine embryos were evaluated. In vitro-produced blastocysts were divided into two groups: the control group (CG) without the addition of LpAFP and the treatment group (TG) with the addition of 500 ng/ml of LpAFP in the equilibrium and vitrification solution. Vitrification was carried out by transferring the blastocysts to the equilibrium solution [7.5% ethylene glycol (EG) and 7.5% dimethyl sulfoxide (DMSO)] for 2 min and then to the vitrification solution (15% EG, 15% DMSO and 0.5M sucrose). The blastocysts were deposited on a cryotop device and submerged in liquid nitrogen. Warming was carried out in three steps in solutions with different sucrose concentrations (1.0, 0.5, and 0.0 M, respectively). Embryos were evaluated for re-expansion/hatching, the total cell count, and ultrastructural analysis. There was no significant difference in the re-expansion rate 24 h after warming; however, there was variation (P < 0.05) in the hatching rate in the TG and the total number of cells 24 h after warming was higher in the TG (114.87 ± 7.24) when compared with the CG (91.81 ± 4.94). The ultrastructural analysis showed changes in organelles related to the vitrification process but, in the TG, there was less damage to mitochondria and rough endoplasmic reticulum compared with the CG. In conclusion, the addition of 500 ng/ml of LpAFP during the vitrification of in vitro-produced bovine embryos improved the hatching rate and total cell number of blastocysts after warming and mitigated intracellular damage.


Assuntos
Lolium , Vitrificação , Bovinos , Animais , Dimetil Sulfóxido/farmacologia , Criopreservação , Fertilização in vitro , Crioprotetores/farmacologia , Blastocisto , Etilenoglicol/farmacologia
3.
Arq. bras. med. vet. zootec. (Online) ; 75(2): 333-346, Mar.-Apr. 2023. tab
Artigo em Inglês | VETINDEX | ID: biblio-1434375

RESUMO

This study aimed to evaluate the effect of the inclusion of spineless cactus (Opuntia stricta Haw) in the diet of sheep on the balance of macrominerals, renal function, and blood metabolites. Five sheep cannulated in the rumen (61.5±9.5kg body weight) were used in a 5 × 5 Latin square composed of five diets and five experimental periods. The experimental period lasted 105 days, with five periods of 21 days each. Four diets containing levels of spineless cactus (121, 245, 371, and 500g/kg of dry matter (DM)), and a control diet were evaluated. Samples of the ingredients, orts, feces, urine, and blood were collected. Spineless cactus inclusion in sheep diets increased the DM intake, ash, oxalate, and all macrominerals intake (P < 0.05), but did not affect the urinary and fecal excretion of P, as well as the concentration of P in the blood (P > 0.05). It is possible to verify that the inclusion of spineless cactus, up to the level of 500g/kg of DM in the sheep diets, does not appear to cause damage to the animal's health. Its inclusion does not compromise kidney function or blood metabolites evaluated herein.


O objetivo deste estudo foi avaliar o efeito da inclusão de palma forrageira (Opuntia stricta Haw) na dieta de ovinos sobre o balanço dos macrominerais, a função renal e os metabólitos sanguíneos. Cinco ovinos canulados no rúmen (61,5±9,5kg de peso corporal) foram distribuídos em um quadrado de 5 × 5 latinos, composto de cinco dietas e cinco períodos experimentais. O período experimental teve duração de 105 dias, sendo cinco períodos de 21 dias cada. Foram avaliadas quatro dietas contendo níveis de palma forrageira (121, 245, 371 e 500g/kg de matéria seca (MS)), e uma dieta controle. Foram coletadas amostras dos ingredientes, sobras, fezes, urina e sangue. A inclusão de palma forrageira na dieta dos ovinos aumentou o consumo de MS, cinzas, oxalato e todos os macrominerais (P<0,05), mas não afetou a excreção urinária e a fecal de P, bem como a concentração de P no sangue (P>0,05). É possível verificar que a inclusão de palma forrageira, até o nível de 500g/kg de MS na dieta de ovinos, não parece causar danos à saúde do animal. Sua inclusão não compromete a função renal ou os metabólitos sanguíneos avaliados.


Assuntos
Animais , Ovinos , Opuntia , Dieta/veterinária , Rim
4.
JBRA Assist Reprod ; 27(1): 78-84, 2023 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-36995260

RESUMO

OBJECTIVE: Follicle-stimulating hormone (FSH) is essential for folliculogenesis, acting through the follicle-stimulating hormone receptor (FSHR) that is present on the membrane of granulosa cells. Polymorphisms in the FSHR gene may lead to an altered pattern of receptor expression on the cell surface or to changes in affinity for FSH. The aim of this prospective study was to detect any association between the follicle-stimulating hormone receptor (FSHR) gene Ala307Thr polymorphism (rs6165) and ovarian reserve, ovarian response or clinical results in IVF/ICSI treatment. METHODS: This prospective cohort study included 450 women who underwent IVF/ICSI cycles. DNA was extracted from peripheral blood, and the Ala307Thr FSHR polymorphism (rs6165) was genotyped using the TaqMan SNP genotyping assay. Participants were divided into three groups according to their Ala307Thr FSHR genotype: Thr/Thr (n:141), Thr/Ala (n=213) and Ala/Ala (n=96). The results were tested for associations with age, anti-Mullerian hormone (AMH) levels, antral follicle count (AFC), total dose of r-FSH, follicle size, number of retrieved oocytes, and clinical outcome of IVF/ICSI cycles. The statistical analyses were performed using Fisher's exact test and the Kruskal‒Wallis test. RESULTS: An association between the genotype of the FSHR (Ala307Thr) polymorphism and the dose of r-FSH was observed. Patients with the Ala/Ala genotype received a higher r-FSH dose than patients with the Ala/Thr (p=0.0002) and Thr/Thr (p=0.02) genotypes. No other correlation was observed. CONCLUSION: The Ala/Ala genotype was associated with the use of higher doses of recombinant FSH (r-FSH), suggesting that homozygosis of this allelic variant (Ala) provides lower sensitivity to r-FSH.


Assuntos
Receptores do FSH , Injeções de Esperma Intracitoplásmicas , Feminino , Animais , Receptores do FSH/genética , Receptores do FSH/metabolismo , Estudos Prospectivos , Indução da Ovulação/métodos , Hormônio Foliculoestimulante/uso terapêutico , Hormônio Foliculoestimulante Humano/uso terapêutico , Fertilização in vitro/métodos
5.
Braz J Med Biol Res ; 56: e12475, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36722661

RESUMO

The systematic assessment of cognitive performance of older people without cognitive complaints is controversial and unfeasible. Identifying individuals at higher risk of cognitive impairment could optimize resource allocation. We aimed to develop and test machine learning models to predict cognitive impairment using variables obtainable in primary care settings. In this cross-sectional study, we included 8,291 participants of the baseline assessment of the ELSA-Brasil study, who were aged between 50 and 74 years and were free of dementia. Cognitive performance was assessed with a neuropsychological battery and cognitive impairment was defined as global cognitive z-score below 2 standard deviations. Variables used as input to the prediction models included demographics, social determinants, clinical conditions, family history, lifestyle, and laboratory tests. We developed machine learning models using logistic regression, neural networks, and gradient boosted trees. Participants' mean age was 58.3±6.2 years, 55% were female. Cognitive impairment was present in 328 individuals (4%). Machine learning algorithms presented fair to good discrimination (areas under the ROC curve between 0.801 and 0.873). Extreme Gradient Boosting presented the highest discrimination, high specificity (97%), and negative predictive value (97%). Seventy-six percent of the individuals with cognitive impairment were included among the highest ranked individuals by this algorithm. In conclusion, we developed and tested a machine learning model to predict cognitive impairment based on primary care data that presented good discrimination and high specificity. These characteristics could support the detection of patients who would not benefit from cognitive assessment, facilitating the allocation of human and economic resources.


Assuntos
Disfunção Cognitiva , Humanos , Idoso , Pessoa de Meia-Idade , Estudos Transversais , Disfunção Cognitiva/diagnóstico , Aprendizado de Máquina , Tomada de Decisões , Atenção Primária à Saúde
6.
Int J Educ Dev ; 99: 102753, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36852098

RESUMO

In Brazil, schools remained closed to prevent the spread of COVID-19 for approximately two years. In this study, we investigated how COVID-19 school closures were associated with gaps and losses in Brazilian students' reading skills. We contrasted the reading comprehension and fluency of 2nd- to 4th-graders in 2022 with a 2019 cohort. Furthermore, we investigated how 2022 5th graders' reading comprehension and fluency skills have improved since 2019. Overall, results showed that COVID-19 school closures were associated with gaps but not losses in reading comprehension and fluency. Therefore, these skills should be targets of educational interventions.

7.
Eur J Prosthodont Restor Dent ; 31(3): 214-223, 2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-36515423

RESUMO

OBJECTIVE: The antimicrobial effect of prosthetic materials treated with chitosan was systematically reviewed. METHODS: The searches were carried out on PubMed/Medline, Scopus, ISI Web of Science, LILACS, Embase, and Open Grey with searches performed in March 2022. Selection of in vitro studies, data extraction and risk of bias analysis were performed following the PRISMA guidelines and registered at the Open Science Framework. The evaluated prosthetic materials corresponded to PMMA and tissue conditioner, treated with chitosan. RESULTS: After evaluating the eligibility criteria, 11 articles were included for the qualitative synthesis. The evaluated prosthetic materials corresponded to PMMA (n=8) and tissue conditioner (n=3). All studies performed the incorporation of chitosan in the tissue conditioner (n=3). Regarding PMMA, the use of chitosan as a denture cleanser was the most used (n=3), followed by incorporation (n=2), multilayers coating onto PMMA (n=2) and denture adhesive for PMMA (n=1). Chitosan has antimicrobial activity and is effective in the treatment of prosthetic materials in most studies, but it depends on some factors, such as the treatment method, the type and characteristics of the chitosan, the microorganism evaluated, and its form of organization. CONCLUSION: Chitosan showed highly antimicrobial activity and was effective when used in prosthetic materials.


Assuntos
Anti-Infecciosos , Quitosana , Quitosana/farmacologia , Polimetil Metacrilato , Anti-Infecciosos/farmacologia , Teste de Materiais
8.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;56: e12475, 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1420748

RESUMO

The systematic assessment of cognitive performance of older people without cognitive complaints is controversial and unfeasible. Identifying individuals at higher risk of cognitive impairment could optimize resource allocation. We aimed to develop and test machine learning models to predict cognitive impairment using variables obtainable in primary care settings. In this cross-sectional study, we included 8,291 participants of the baseline assessment of the ELSA-Brasil study, who were aged between 50 and 74 years and were free of dementia. Cognitive performance was assessed with a neuropsychological battery and cognitive impairment was defined as global cognitive z-score below 2 standard deviations. Variables used as input to the prediction models included demographics, social determinants, clinical conditions, family history, lifestyle, and laboratory tests. We developed machine learning models using logistic regression, neural networks, and gradient boosted trees. Participants' mean age was 58.3±6.2 years, 55% were female. Cognitive impairment was present in 328 individuals (4%). Machine learning algorithms presented fair to good discrimination (areas under the ROC curve between 0.801 and 0.873). Extreme Gradient Boosting presented the highest discrimination, high specificity (97%), and negative predictive value (97%). Seventy-six percent of the individuals with cognitive impairment were included among the highest ranked individuals by this algorithm. In conclusion, we developed and tested a machine learning model to predict cognitive impairment based on primary care data that presented good discrimination and high specificity. These characteristics could support the detection of patients who would not benefit from cognitive assessment, facilitating the allocation of human and economic resources.

9.
Arq. bras. med. vet. zootec. (Online) ; 75(1): 48-60, 2023. tab
Artigo em Inglês | VETINDEX | ID: biblio-1416490

RESUMO

This study aimed to evaluate the effects of partial replacement (750g/kg) of Tifton hay by two cactus cladodes (Nopalea or Opuntia) on the metabolic profile of lambs. Thirty-six uncastrated male Santa Inês lambs (22.0±2.9kg initial body weight) were distributed in a completely randomized design, with three treatments and 12 repetitions. The animals were fed a control diet (Tifton hay as exclusive roughage), Miúda cactus cladodes-based diet or Orelha de Elefante Mexicana (O.E.M.) cactus cladodes-based diet. Blood samples were collected one day before (baseline) and 45 days after the introduction of the tested diets. The Miúda cactus cladodes caused an increase (P=0.055) in the serum activity of the gamma-glutamyl transferase enzyme (53.66U/L) and in the blood content of glucose and fructosamine. The O.E.M. cactus cladodes caused lower (P=0.038) serum cholesterol content (41.33mg/dL). Regardless of the variety, there was a decrease (P=0.001) in the serum content of indirect bilirubin, urea, and sodium, and increase in the serum magnesium concentration. The partial replacement of the Tifton hay by Miúda or O.E.M. cactus cladodes in lamb feeding increases the enzyme activity, indicating liver and/or kidney changes, but does not cause relevant damage to energy, protein, and mineral metabolism.


Este trabalho teve como objetivo avaliar os efeitos da substituição parcial (750g/kg) do feno de Tifton por duas variedades de palma forrageira (Nopalea ou Opuntia) no perfil metabólico de cordeiros. Trinta e seis cordeiros Santa Inês, machos, não castrados (22,0 ± 2,9kg de peso corporal inicial), foram distribuídos em delineamento inteiramente ao acaso, com três tratamentos e 12 repetições. Os animais foram alimentados com dieta controle (feno de Tifton como volumoso exclusivo), dieta à base de palma forrageira Miúda ou dieta à base de palma forrageira Orelha de Elefante Mexicana (OEM). Amostras de sangue foram coletadas um dia antes (baseline) e 45 dias após a introdução das dietas testadas. A palma Miúda causou aumento (P=0,055) na atividade sérica da enzima gamaglutamiltransferase (53,66U/L) e no teor sanguíneo de glicose e frutosamina. A palma OEM causou menor teor (P=0,038) de colesterol sérico (41,33mg/dL). Independentemente da variedade, houve diminuição (P=0,001) do teor sérico de bilirrubina indireta, ureia e sódio, e aumento na concentração sérica de magnésio. A substituição parcial do feno de Tifton por palma Miúda ou por OEM na alimentação de cordeiros aumenta a atividade enzimática, o que indica alterações hepáticas e/ou renais, mas não causa danos relevantes nos metabolismos energético, proteico e mineral.


Assuntos
Animais , Masculino , Ovinos/metabolismo , Cactaceae/química , Ração Animal/análise , Análise Química do Sangue/veterinária , Zona Semiárida
10.
Cogn Neurodyn ; 16(6): 1461-1470, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36408063

RESUMO

Neuronal spike variability is a statistical property associated with the noise environment. Considering a linearised Hodgkin-Huxley model, we investigate how large spike variability can be induced in a typical stellate cell when submitted to constant and noise current amplitudes. For low noise current, we observe only periodic firing (active) or silence activities. For intermediate noise values, in addition to only active or inactive periods, we also identify a single transition from an initial spike-train (active) to silence dynamics over time, where the spike variability is low. However, for high noise current, we find intermittent active and silence periods with different values. The spike intervals during active and silent states follow the exponential distribution, which is similar to the Poisson process. For non-maximal noise current, we observe the highest values of inter-spike variability. Our results suggest sub-threshold oscillations as a possible mechanism for the appearance of high spike variability in a single neuron due to noise currents.

12.
J Appl Stat ; 49(1): 195-213, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35707798

RESUMO

In regression model applications, the errors may frequently present a symmetric shape. In such cases, the normal and Student t distributions are commonly used. In this paper, we shall be concerned only to model heavy-tailed, skewed errors and absence of variance homogeneity with two regression structures based on the skew t distribution. We consider a classic analysis for the parameters of the proposed model. We perform a diagnostic analysis based on global influence and quantile residuals. For different parameter settings and sample sizes, various simulation results are obtained and compared to evaluate the performance of the skew t regression. Further, we illustrate the usefulness of the new regression by means of a real data set (amount of potassium in different soil areas) from a study carried out at the Department of Soil Science of the Luiz de Queiroz School of Agriculture, University of São Paulo.

13.
Arq. bras. med. vet. zootec. (Online) ; 73(5): 1209-1216, Sept.-Oct. 2021. tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1345274

RESUMO

The objective was to evaluate the intake and digestibility of nutrients, ingestive behavior, and performance of goats fed with spineless cactus genotypes resistant to carmine cochineal (Miúda or Orelha de Elefante Mexicana (OEM). Thirty castrated male goats, without defined breed, aged 12 to 14 months, with an average body weight of 19.0±2.8kg, were distributed in a completely randomized design among three treatments (Control - Tifton hay, Miúda, and OEM) and ten replicates; the initial weight was considered as the covariate. The intake of organic matter (OM), neutral detergent fiber (NDF) was highest in the control treatment, while the intake of NFC was higher in the OEM diet. Treatments containing forage cactus showed the highest digestibility of DM, OM, and NFC. The animals fed the control diet spent more time on rumination and total chewing, but the time spent feeding or feeding efficiency, and performance did not differ. The use of spineless cactus genotypes resistant to carmine cochineal (Miúda and Orelha de Elefante Mexicana) in a diet for goats, in the amount of 450g/kg of DM does not interfere with the performance of the animals and improves the digestibility of OM and NFC.(AU)


Objetivou-se com o presente estudo avaliar o consumo e a digestibilidade de nutrientes, o comportamento ingestivo e o desempenho de caprinos alimentados com genótipos de palma forrageira resistentes à cochonilha-carmim (miúda ou orelha-de-elefante-mexicana (OEM). Trinta cabritos machos, castrados, sem raça definida, com idades entre 12 e 14 meses e peso corporal médio de 19,0±2,8kg, foram distribuídos em delineamento inteiramente ao acaso, em três tratamentos (controle - feno de tifton; miúda e OEM) e 10 repetições; o peso inicial foi considerado a covariável. O consumo de matéria orgânica (MO) e de fibra em detergente neutro (FDN) foi maior no tratamento controle; enquanto a ingestão de CNF foi maior na dieta OEM. Tratamentos contendo palma forrageira apresentaram as maiores digestibilidades de MS, MO e CNF. Os animais alimentados com a dieta controle gastaram mais tempo em ruminação e em mastigação total, mas o tempo gasto com alimentação ou a eficiência alimentar e o desempenho não diferiram. A utilização de genótipos de palma forrageira resistentes à cochonilha-carmim (miúda e orelha-de-elefante-mexicana) na dieta de caprinos, na quantidade de 450g/kg de MS, não interfere no desempenho dos animais e melhora a digestibilidade de MO e CNF.(AU)


Assuntos
Animais , Masculino , Cabras , Cactaceae , Dieta , Ração Animal , Ruminação Digestiva , Hemípteros
14.
Braz J Med Biol Res ; 54(10): e11439, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34378678

RESUMO

Cathepsin Z (CTSZ) is a cysteine protease responsible for the adhesion and migration of both immune and tumor cells. Due to its dual role, we hypothesized that the site of CTSZ expression could be determinant of the pro- or anti-tumorigenic effects of this enzyme. To test this hypothesis, we analyzed CTSZ expression data in healthy and tumor tissues by bioinformatics and evaluated the expression levels of CTSZ mRNA in the blood cells of prostate cancer (PCa) patients by qRT-PCR compared with healthy subjects, evaluating its diagnostic and prognostic implications for this type of cancer. Immune cells present in the blood of healthy patients overexpress CTSZ. In PCa, we found decreased CTSZ mRNA levels in blood cells, 75% lower than in healthy subjects, that diminished even more during biochemical relapse. CTSZ mRNA in the blood cells had an area under the curve for PCa diagnosis of 0.832, with a 93.3% specificity, and a positive likelihood ratio of 9.4. The site of CTSZ mRNA expression is fundamental to determine its final role as a protective determinant in PCa, such as CTSZ mRNA in the blood cells, or a malignant determinant, such as found for CTSZ expressed in high levels by different types of primary and metastatic tumors. Low CTSZ mRNA expression in the total blood is a possible PCa marker complementary to prostate-specific antigen (PSA) for biopsy decisions, with the potential to eliminate unnecessary biopsies.


Assuntos
Catepsina Z , Neoplasias da Próstata , Células Sanguíneas , Humanos , Masculino , Prognóstico , Antígeno Prostático Específico , Neoplasias da Próstata/diagnóstico , RNA Mensageiro
15.
JBRA Assist Reprod ; 25(3): 466-472, 2021 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-34224237

RESUMO

OBJECTIVE: It is generally accepted that the incidence of birth defects in spontaneously conceived children ranges between 2.0-4.0%. However, several studies have shown that babies born after assisted reproductive technology (ART) procedures tend to present more congenital malformations than naturally conceived children, with 6.5% of the children born after intracytoplasmic sperm injection (ICSI) presenting birth defects. The use of high magnification sperm selection before ICSI was introduced in the early 2000s to allow the identification of spermatozoa with low risk of sperm DNA damage. Intracytoplasmic morphologically selected sperm injection (IMSI) is expected to change the incidence of congenital malformations, although data on the incidence of birth defects in children conceived after IMSI are still scarce. METHODS: A systematic review based on searches performed in electronic databases (PubMed, EMBASE, Web of Science, SCOPUS, and Cochrane Central Register of Controlled Trials) including articles published by February 2021 was conducted to identify trials comparing the neonatal outcomes of ICSI and IMSI. The outcome measured was the rate of birth defects in children born after ICSI or IMSI. Three trials were included as targets for data extraction and meta-analysis. RESULTS: Our meta-analysis included 3907 children conceived after IMSI (1280) or ICSI (2627). The incidence of birth defects was statistically different, with 2.5% (32/1280) in IMSI and 4.5% (119/2627) in ICSI (RR=0.59; 95% CI=0.40-0.87; p=0.007). The results demonstrated that IMSI decreased the incidence of structural defects compared to ICSI - 2.2% (18/830) vs. 3.8% (78/2049) - in a statistically significant manner (RR=0.58; 95%CI=0.35-0.96; p=0.04). No significant difference was observed in chromosomal abnormalities (Trisomy 13; 18; 21 and Triple X) between children conceived after IMSI (8/830) or ICSI (19/2049) (RR=1.07; 95%CI=0.47-2.43; p=0.87). CONCLUSIONS: IMSI seems to be an effective tool at reducing the incidence of structural defects compared to ICSI. However, IMSI does not change the incidence of chromosomal abnormalities.


Assuntos
Injeções de Esperma Intracitoplásmicas , Espermatozoides , Criança , Feminino , Humanos , Recém-Nascido , Masculino , Gravidez , Taxa de Gravidez , Técnicas de Reprodução Assistida , Injeções de Esperma Intracitoplásmicas/efeitos adversos
16.
Zygote ; 29(6): 445-451, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33906701

RESUMO

This study evaluated the effects of leptin on primordial follicle survival and activation after in vitro culture of ovine ovarian tissue and if leptin acts through the phosphatidylinositol-3-kinase/protein kinase B (PI3K/Akt) pathway. Ovarian fragments were fixed for histology (fresh control) or cultured for 7 days in control medium (α-MEM+) alone or supplemented with leptin (1, 5, 10, 25 or 50 ng/ml). Follicle morphology, activation and apoptosis were analyzed. Next, the fragments were cultured in the medium that showed the best results in the absence or the presence of the PI3K inhibitor (LY294002), and immunohistostaining of p-Akt protein was assessed. After culture, the percentage of normal follicles decreased (P < 0.05) in all treatments compared with the fresh control. Moreover, control medium and 1 ng/ml leptin had similar (P > 0.05) percentages of normal follicles, which were significantly higher than those in other treatments. However, culture with 1 ng/ml leptin maintained apoptosis similarly (P > 0.05) to that of the fresh control and lower (P < 0.05) than that in α-MEM+. Leptin did not influence follicle activation (P > 0.05) compared with the control medium (α-MEM+). Culture in 1 ng/ml leptin with LY294002 decreased the normal follicles and increased apoptosis, inhibited follicle activation (P < 0.05), and reduced p-Akt immunostaining, compared with the medium containing 1 ng/ml leptin without PI3K inhibitor. In conclusion, leptin at 1 ng/ml reduces apoptosis and promotes the activation of primordial follicles compared with the fresh control after in vitro culture of ovine ovarian tissue possibly through the PI3K/Akt pathway.


Assuntos
Apoptose , Leptina/farmacologia , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Animais , Feminino , Ovário , Fosfatidilinositóis , Ovinos , Técnicas de Cultura de Tecidos
17.
Eur Arch Paediatr Dent ; 22(2): 301-306, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33025398

RESUMO

PURPOSE: The knowledge of the stress related to the practice of paediatric dentistry is scarce. The aim of this study was to verify the stress perceived by paediatric dentists related to young children's dental treatment under sedation and their association with child's behaviour and other independent variables. METHODS: A cross-sectional repeated measures study was performed with four paediatric dentists who treated 81 sedated preschoolers. Paediatric dentists reported their stress at the end of the session using the visual analog scale (VAS 0-100 mm). Samples of saliva were collected to measure the dentists' salivary cortisol level throughout the dental session. The sessions of dental treatment were video recorded for evaluation of the child's behaviour. Children's behaviour was assessed using the Ohio State University Behavioral Rating Scale (OSUBRS). The association between the VAS scores and the other variables was verified using bivariate tests and generalised estimating equation (alpha 0.05). RESULTS: Paediatric dentists felt slightly stressed in most of the sessions (VAS median 7 points; minimum 0, maximum 97 points). VAS associated with the struggling behaviour of the child (B 0.53; 95%CI 0.32-0.74; p ≤ 0.001) and the time since dentist's graduation (B - 1.41, 95% CI - 1.87 to - 0.94; p ≤ 0.001) but not with dentist's salivary cortisol (rho - 0.053, p = 0.639). CONCLUSION: The more frequent the child's struggling behaviour during dental treatment and the shorter the time elapsed since the professional's graduation, the higher the level of objectively and subjectively measured stress of the paediatric dentist during the dental procedure.


Assuntos
Assistência Odontológica para Crianças , Atitude do Pessoal de Saúde , Criança , Pré-Escolar , Estudos Transversais , Odontólogos , Humanos , Odontopediatria , Saliva
18.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;54(10): e11439, 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1285649

RESUMO

Cathepsin Z (CTSZ) is a cysteine protease responsible for the adhesion and migration of both immune and tumor cells. Due to its dual role, we hypothesized that the site of CTSZ expression could be determinant of the pro- or anti-tumorigenic effects of this enzyme. To test this hypothesis, we analyzed CTSZ expression data in healthy and tumor tissues by bioinformatics and evaluated the expression levels of CTSZ mRNA in the blood cells of prostate cancer (PCa) patients by qRT-PCR compared with healthy subjects, evaluating its diagnostic and prognostic implications for this type of cancer. Immune cells present in the blood of healthy patients overexpress CTSZ. In PCa, we found decreased CTSZ mRNA levels in blood cells, 75% lower than in healthy subjects, that diminished even more during biochemical relapse. CTSZ mRNA in the blood cells had an area under the curve for PCa diagnosis of 0.832, with a 93.3% specificity, and a positive likelihood ratio of 9.4. The site of CTSZ mRNA expression is fundamental to determine its final role as a protective determinant in PCa, such as CTSZ mRNA in the blood cells, or a malignant determinant, such as found for CTSZ expressed in high levels by different types of primary and metastatic tumors. Low CTSZ mRNA expression in the total blood is a possible PCa marker complementary to prostate-specific antigen (PSA) for biopsy decisions, with the potential to eliminate unnecessary biopsies.


Assuntos
Humanos , Masculino , Neoplasias da Próstata/diagnóstico , Catepsina Z , Prognóstico , Células Sanguíneas , RNA Mensageiro , Antígeno Prostático Específico
19.
JBRA Assist Reprod ; 24(4): 391-393, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-32902935

RESUMO

Perhaps with the intention of obtaining larger amounts of free-DNA, some groups are routinely postponing and establishing free-DNA collection in culture medium for Noninvasive preimplantation genetic testing for aneuploidies (niPGT-A) to day 6 for all blastocysts. A meta-analysis served as the basis for such decision, since statistically similar live birth rates were observed when the transfers of euploid blastocysts were performed on day 5 versus day 6 However, the euploidy analysis was conducted in only two studies However, after including the two more studies we performed a new meta-analysis that clearly showed the risks of losing live births with the decision of adopting the 6th day as the endpoint for gathering free-DNA. We would be losing 1.71x more live births.


Assuntos
Aneuploidia , Transtornos Cromossômicos/diagnóstico , Testes Genéticos , Diagnóstico Pré-Implantação , Transtornos Cromossômicos/genética , Feminino , Humanos , Gravidez
20.
Braz J Med Biol Res ; 53(6): e9113, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32401924

RESUMO

Chemerin is an adipokine that has been associated with components of metabolic syndrome. It has been described to affect adipocyte metabolism and inflammatory responses in adipose tissue, as well as the systemic metabolism of lipids and glucose. Few epidemiological studies have evaluated classical and genetics cardiovascular risk factors (CVRFs) in the mixed adult rural population in Brazil. Therefore, the present study explored possible associations between CVRFs and chemerin. This cross-sectional study included 508 adults from the rural localities of Lavras Novas, Chapada, and Santo Antônio do Salto in Ouro Preto, Minas Gerais, Southeast Brazil. Demographic, behavioral, clinical, biochemical, anthropometric variables, and 12 single nucleotide polymorphisms (SNPs) linked with metabolic syndrome phenotypes were evaluated for associations with chemerin level. There was a significant association of high triglyceride levels [odds ratio (OR)=1.91, 95%CI: 1.23-2.98], insulin resistance (OR=1.82, 95%CI: 1.03-3.22), age (OR=1.64, 95%CI: 1.08-2.49), and sex (OR=1.99, 95%CI: 1.35-2.95) with high levels of chemerin. High chemerin levels were significantly associated with the genetic polymorphisms rs693 in the APOB gene (OR=1.50, 95%CI: 1.03-2.19) and rs1799983 in the NOS3 gene (OR=1.46, 95%CI: 1.01-2.12) for the AA and GT+TT genotypes, respectively. In the concomitant presence of genotypes AA of rs693 and GT+TT of rs1799983, the chance of presenting high levels of chemerin showed a 2.21-fold increase (95%CI: 1.25-3.88) compared to the reference genotype. The development of classical CVRFs in this population may be influenced by chemerin and by two risk genotypes characteristic of variants in well-studied genes for hypertension and dyslipidemia.


Assuntos
Apolipoproteínas B/genética , Doenças Cardiovasculares/genética , Quimiocinas/sangue , Óxido Nítrico Sintase Tipo III/genética , Polimorfismo de Nucleotídeo Único/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Brasil , Doenças Cardiovasculares/metabolismo , Quimiocinas/genética , Estudos Transversais , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , População Rural , Adulto Jovem
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