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1.
Genes (Basel) ; 15(7)2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39062715

RESUMEN

BACKGROUND: Neonatal health assessment is crucial for detecting and intervening in various disorders. Traditional gene expression analysis methods often require invasive procedures during sample collection, which may not be feasible or ideal for preterm infants. In recent years, saliva has emerged as a promising noninvasive biofluid for assessing gene expression. Another trend that has been growing is the use of "omics" technologies such as transcriptomics in the analysis of gene expression. The costs for carrying out these analyses and the difficulty of analysis make the detection of candidate genes necessary. These genes act as biomarkers for the maturation stages of the oral feeding issue. METHODOLOGY: Salivary samples (n = 225) were prospectively collected from 45 preterm (<34 gestational age) infants from five predefined feeding stages and submitted to RT-qPCR. A better description of the targeted genes and results from RT-qPCR analyses were included. The six genes previously identified as predictive of feeding success were tested. The genes are AMPK, FOXP2, WNT3, NPHP4, NPY2R, and PLXNA1, along with two reference genes: GAPDH and 18S. RT-qPCR amplification enabled the analysis of the gene expression of AMPK, FOXP2, WNT3, NPHP4, NPY2R, and PLXNA1 in neonatal saliva. Expression results were correlated with the feeding status during sample collection. CONCLUSIONS: In summary, the genes AMPK, FOXP2, WNT3, NPHP4, NPY2R, and PLXNA1 play critical roles in regulating oral feeding and the development of premature infants. Understanding the influence of these genes can provide valuable insights for improving nutritional care and support the development of these vulnerable babies. Evidence suggests that saliva-based gene expression analysis in newborns holds great promise for early detection and monitoring of disease and understanding developmental processes. More research and standardization of protocols are needed to fully explore the potential of saliva as a noninvasive biomarker in neonatal care.


Asunto(s)
Recien Nacido Prematuro , Saliva , Humanos , Saliva/metabolismo , Recién Nacido , Femenino , Masculino , Perfilación de la Expresión Génica/métodos , Transcriptoma/genética
2.
Braz J Microbiol ; 55(3): 2767-2782, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39012425

RESUMEN

Norovirus is an important etiologic agent of acute gastroenteritis and has become even more relevant in Brazil after the implementation of the monovalent rotavirus vaccine in 2006 through the public health system, now representing a significant portion of the etiology of acute diarrheal diseases. Although diagnosing acute gastroenteritis caused by norovirus is a relatively simple process, and the infection tends to be self-limited, the virus can be considerably harmful to vulnerable populations, such as children, the elderly, and immunocompromised individuals. The spread of norovirus is also particularly favorable among such groups due to its mode of transmission, favored by cluttered environments such as in hospitals and densely populated regions. Additionally, norovirus' ability to spread through water and food creates the need for measures to ensure adequate sanitation and the development of effective measures to prevent outbreaks and severe manifestations of the disease. This review aims to address the main reports of human norovirus detected in Brazil over the years, focusing on clinical-hospital, food-related, and urban conglomerate contexts, including the circulating strains.


Asunto(s)
Infecciones por Caliciviridae , Gastroenteritis , Norovirus , Norovirus/genética , Norovirus/aislamiento & purificación , Norovirus/clasificación , Brasil/epidemiología , Humanos , Infecciones por Caliciviridae/epidemiología , Infecciones por Caliciviridae/virología , Gastroenteritis/virología , Gastroenteritis/epidemiología , Brotes de Enfermedades
3.
PLoS Negl Trop Dis ; 18(5): e0011292, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38758957

RESUMEN

BACKGROUND: Leptospirosis is a zoonosis caused by pathogenic species of bacteria belonging to the genus Leptospira. Most studies infer the epidemiological patterns of a single serogroup or aggregate all serogroups to estimate overall seropositivity, thus not exploring the risks of exposure to distinct serogroups. The present study aims to delineate the demographic, socioeconomic and environmental factors associated with seropositivity of Leptospira serogroup Icterohaemorraghiae and serogroup Cynopteri in an urban high transmission setting for leptospirosis in Brazil. METHODS/PRINCIPAL FINDINGS: We performed a cross-sectional serological study in five informal urban communities in the city of Salvador, Brazil. During the years 2018, 2020 2021, we recruited 2.808 residents and collected blood samples for serological analysis using microagglutination assays. We used a fixed-effect multinomial logistic regression model to identify risk factors associated with seropositivity for each serogroup. Seropositivity to Cynopteri increased with each year of age (OR 1.03; 95% CI 1.01-1.06) and was higher in those living in houses with unplastered walls (exposed brick) (OR 1.68; 95% CI 1.09-2.59) and where cats were present near the household (OR 2.00; 95% CI 1.03-3.88). Seropositivity to Icterohaemorrhagiae also increased with each year of age (OR 1.02; 95% CI 1.01-1.03) and was higher in males (OR 1.51; 95% CI 1.09-2.10), in those with work-related exposures (OR 1.71; 95% CI 1.10-2.66) or who had contact with sewage (OR 1.42; 95% CI 1.00-2.03). Spatial analysis showed differences in distribution of seropositivity to serogroups Icterohaemorrhagiae and Cynopteri within the five districts where study communities were situated. CONCLUSIONS/SIGNIFICANCE: Our data suggest distinct epidemiological patterns associated with the Icterohaemorrhagiae and Cynopteri serogroups in the urban environment at high risk for leptospirosis and with differences in spatial niches. We emphasize the need for studies that accurately identify the different pathogenic serogroups that circulate and infect residents of low-income areas.


Asunto(s)
Leptospira interrogans , Leptospira , Leptospirosis , Serogrupo , Leptospirosis/epidemiología , Leptospirosis/microbiología , Leptospirosis/transmisión , Brasil/epidemiología , Humanos , Masculino , Adulto , Femenino , Estudios Transversales , Persona de Mediana Edad , Leptospira/clasificación , Leptospira/inmunología , Leptospira/aislamiento & purificación , Adulto Joven , Adolescente , Leptospira interrogans/inmunología , Leptospira interrogans/clasificación , Leptospira interrogans/aislamiento & purificación , Factores de Riesgo , Estudios Seroepidemiológicos , Población Urbana , Anticuerpos Antibacterianos/sangre , Animales , Niño , Anciano
4.
Genes (Basel) ; 15(5)2024 05 18.
Artículo en Inglés | MEDLINE | ID: mdl-38790270

RESUMEN

BACKGROUND: Diagnosing imprinting defects in neonates and young children presents challenges, often necessitating molecular analysis for a conclusive diagnosis. The isolation of genetic material from oral swabs becomes crucial, especially in settings where blood sample collection is impractical or for vulnerable populations like newborns, who possess limited blood volumes and are often too fragile for invasive procedures. Oral swab samples emerge as an excellent source of DNA, effectively overcoming obstacles associated with rare diseases. METHODS: In our study, we specifically addressed the determination of the quality and quantity of DNA extracted from oral swab samples using NaCl procedures. RESULTS: We compared these results with extractions performed using a commercial kit. Subsequently, the obtained material underwent MS-HRM analysis for loci associated with imprinting diseases such as Prader-Willi and Angelman syndromes. CONCLUSIONS: Our study emphasizes the significance of oral swab samples as a reliable source for obtaining DNA for MS-HRM analysis. NaCl extraction stands out as a practical and cost-effective method for genetic studies, contributing to a molecular diagnosis that proves particularly beneficial for patients facing delays in characterization, ultimately influencing their treatment.


Asunto(s)
Síndrome de Angelman , ADN , Impresión Genómica , Mucosa Bucal , Síndrome de Prader-Willi , Humanos , Mucosa Bucal/citología , Mucosa Bucal/patología , Síndrome de Angelman/genética , Síndrome de Angelman/diagnóstico , Síndrome de Prader-Willi/genética , Síndrome de Prader-Willi/diagnóstico , ADN/genética , ADN/aislamiento & purificación , Cloruro de Sodio , Recién Nacido , Masculino , Trastornos de Impronta
5.
Transl Anim Sci ; 8: txae015, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38371423

RESUMEN

The study investigated the effects of 48-h water and feed deprivation on blood and the performance of grazing Nellore (Bos indicus) heifers. Twenty-four Nellore heifers (initial body weight [BW] = 238 ±â€…10 kg; age = 16 ±â€…2 mo), were ranked by initial BW and age and randomly assigned to one of the two treatments: (1) grazing animals with free access to pasture, water, and mineral-mix (CON; n = 12), or (2) the same grazing conditions but deprived of pasture, water, and mineral-mix for 48 h (DPR; n = 12). The paddocks consisted of Urochloa brizantha cv. Marandu, using a continuous and fixed stocking rate. The experiment lasted 225 d, with the first 14 d considered as the adaptation period (days -14 to -1) and the subsequent 211 d as the evaluation period (days 0 to 211). From days 0 to 2, treatments were applied by keeping the DPR heifers in pens and reintegrating them into the experimental area after a 48-h water and feed deprivation. Individual full BW was recorded on days -14, -13, -1, before (day 0) and after (day 2) treatment application, and on days 6, 11, 12, 41, 42, 210, and 211. Blood samples were collected in the morning on days 0, 2, 6, 12, and 211. A treatment effect was detected (P < 0.001) for shrink BW from days 0 to 2, which was greater (P < 0.001) in DPR vs. CON heifers. Subsequently, DPR animals were lighter (P < 0.001) compared with CON heifers by the end of the deprivation period (day 2). From days 4 to 211, DPR was lighter (P < 0.001) compared with CON heifers after treatment application and for the entire experimental period. In the first 10 d after treatment application (days 2 to 12), DPR heifers showed a partial compensatory average daily gain (ADG; P < 0.001) compared with CON heifers, while no significant differences were observed in ADG between the treatments from days 12 to 42 and 42 to 211 (P > 0.420). Overall ADG (days 2 to 211) was greater (P < 0.001) for DPR vs. CON heifers. All serum variables, except AST, were higher (P < 0.001) in DPR than in CON heifers on day 2 after treatment application. Our study demonstrates that grazing Nellore heifers subjected to 48-h water and feed deprivation experienced significant alterations in their blood metabolites and BW immediately after the stressful event. Although the deprived heifers partially compensated for their BW loss in the early days post-deprivation, they remained 12 kg lighter than the non-deprived animals throughout the production cycle.

6.
Animals (Basel) ; 14(1)2024 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-38200894

RESUMEN

This study evaluated different herbage allowances from mid to late pregnancy on pre- and postpartum physiological responses, milk production, and the performance of Nellore cows and the preweaning growth of their female offspring. Sixty multiparous Nellore cows were blocked by their body weight (BW; 425 ± 36 kg) and body condition score (BCS; 3.67 ± 0.23, scale 1-5) and randomly allocated to twelve pastures. Treatments consisted of two different herbage allowances (HA) during pregnancy: low HA (LHA; 2.80 kg DM/kg of BW) and high HA (HHA; 7.60 kg DM/kg of BW). Both treatment groups were fed 1 g/kg BW of a protein supplement. After calving, all cow-calf pairs were combined in a single group. The effects of maternal treatment × day of the study were detected for herbage mass and allowance, the stocking rate and forage crude protein, and for cow BW, BCS, and carcass measures (p < 0.01). Milk yield corrected to 4% fat, while the levels of fat total solids and cow plasma IGF-1 and urea were different (p ≤ 0.04) between treatments. HHA offspring was heavier (p ≤ 0.05) at 120 days and at weaning. A high herbage allowance can be implemented from mid-gestation until calving to increase cow prepartum performance, post-partum milk yield and composition, and positively modulate female offspring preweaning growth.

7.
Animals (Basel) ; 13(13)2023 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-37444036

RESUMEN

Two studies evaluated the productive characteristics of young Nellore heifers receiving different days on feed (DOF) to determine the biological slaughter endpoint. In Experiment 1 (Exp. 1), fifty-one Nellore heifers [324 ± 19.3 kg of body weight (BW); 16 ± 1 months] were split into three DOF lengths (45, 75, or 105 days), while in Experiment 2 (Exp. 2), thirty-six Nellore heifers (362 ± 25.5 kg of BW; 18 ± 1 months of age) were split into three DOF lengths (45, 90, or 135 days). In both studies, all animals were distributed in complete randomized blocks according to initial BW and stratified via carcass ultrasound. The diet was supplied ad libitum, allowing 3% of refusals. The point at which the animals achieved 25% of ether extract of shrunk body weight (EESBW) was defined as the biological endpoint. Thus, relationships were made between some characteristics obtained in both studies. Positive linear relationships were found between backfat thickness (BFT) vs. EESBW (p < 0.001, r = 0.84) and BFT vs. body weight (p < 0.001, r = 0.77). Our results suggest that the biological slaughter endpoint for young Nellore heifers is 6.97 mm of backfat thickness or 402 kg shrunk body weight, corresponding to around 75 DOF.

8.
medRxiv ; 2023 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-37090569

RESUMEN

Background: Leptospirosis is a zoonosis caused by pathogenic species of bacteria belonging to the genus Leptospira. Most studies infer the epidemiological patterns of a single serogroup or aggregate all serogroups to estimate overall seropositivity, thus not exploring the risks of exposure to distinct serogroups. The present study aims to delineate the demographic, socioeconomic and environmental factors associated with seropositivity of Leptospira serogroup Icterohaemorraghiae and serogroup Cynopteri in an urban high transmission setting for leptospirosis in Brazil. Methods/Principal Findings: We performed a cross-sectional serological study in five urban informal communities in the city of Salvador, Brazil. During the years 2018, 2020 2021, we recruited 2.808 residents and collected blood samples for serological analysis using microagglutination assays. We used a mixed-effect multinomial logistic regression model to identify risk factors associated with seropositivity for each serogroup. Seropositivity to Cynopteri increased with age in years (OR 1.03; 95% CI 1.01-1.06) and was higher in those living in houses with unplaster walls (exposed brick) (OR 1.68; 95% CI 1.09-2.59) and where cats were present near the household (OR 2.00; 95% CI 1.03-3.88). Seropositivity to Icterohaemorrhagiae also increased with age in years (OR 1.02; 95% CI 1.01-1.03) but was higher in males (OR 1.51; 95% CI 1.09-2.10), in those with work-related exposures (OR 1.71; 95% CI 1.10-2.66) or who had contact with sewage (OR 1.42; 95% CI 1.00-2.03). Spatial analysis showed differences in distribution of seropositivity to serogroups Icterohaemorrhagiae and Cynopteri within the five districts where study communities were situated. Conclusions/Significance: Our data suggests distinct epidemiological patterns associated with serogroups Icterohaemorrhagiae and Cynopteri within the high-risk urban environment for leptospirosis and with differences of spatial niches. Future studies must identify the different pathogenic serogroups circulating in low-income areas, and further evaluate the potential role of cats in the transmission of the serogroup Cynopteri in urban settings.

9.
Glob Chang Biol ; 29(11): 3098-3113, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36883779

RESUMEN

Fragmented tropical forest landscapes preserve much of the remaining biodiversity and carbon stocks. Climate change is expected to intensify droughts and increase fire hazard and fire intensities, thereby causing habitat deterioration, and losses of biodiversity and carbon stock losses. Understanding the trajectories that these landscapes may follow under increased climate pressure is imperative for establishing strategies for conservation of biodiversity and ecosystem services. Here, we used a quantitative predictive modelling approach to project the spatial distribution of the aboveground biomass density (AGB) by the end of the 21st century across the Brazilian Atlantic Forest (AF) domain. To develop the models, we used the maximum entropy method with projected climate data to 2100, based on the Intergovernmental Panel on Climate Change Representative Concentration Pathway (RCP) 4.5 from the fifth Assessment Report. Our AGB models had a satisfactory performance (area under the curve > 0.75 and p value < .05). The models projected a significant increase of 8.5% in the total carbon stock. Overall, the projections indicated that 76.9% of the AF domain would have suitable climatic conditions for increasing biomass by 2100 considering the RCP 4.5 scenario, in the absence of deforestation. Of the existing forest fragments, 34.7% are projected to increase their AGB, while 2.6% are projected to have their AGB reduced by 2100. The regions likely to lose most AGB-up to 40% compared to the baseline-are found between latitudes 13° and 20° south. Overall, although climate change effects on AGB vary latitudinally for the 2071-2100 period under the RCP 4.5 scenario, our model indicates that AGB stocks can potentially increase across a large fraction of the AF. The patterns found here are recommended to be taken into consideration during the planning of restoration efforts, as part of climate change mitigation strategies in the AF and elsewhere in Brazil.


Asunto(s)
Ecosistema , Árboles , Biomasa , Brasil , Cambio Climático , Bosques , Carbono , Clima Tropical
10.
J Biomed Mater Res B Appl Biomater ; 111(4): 881-894, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36440654

RESUMEN

Bone infection treatment is a significant challenge for the orthopedic field. 3D printing is a promising technology to produce scaffolds with customized architecture, able to stimulate and support bone growth. ß-TCP and S53P4 bioactive glass (BG) are well-known biomaterials for scaffold manufacturing. However, a multifunctional scaffold, able to inhibit microbial proliferation at the defect site, is of increasing interest to avoid infection recurrence. Tea tree oil (TTO) has aroused interest as an antimicrobial agent to minimize the use of antibiotics. Therefore, combining the regenerative potential of a bioceramic with TTO's antimicrobial properties could result in a scaffold capable of stimulating tissue growth and treating infections. In this context, this study aimed to produce and characterize 3D-printed ß-TCP/S53P4 BG scaffolds coated with TTO. Scaffolds morphological and chemical characterizations were carried out through XDR, SEM, and FTIR analysis. ß-TCP/S53P4 BG scaffolds showed a compressive strength of ~2 MPa and 53 ± 2% of porosity. The scaffolds were coated by two different procedures, using an ethanol/TTO (EtOH/TTO) and a gelatin/TTO (Gel/TTO) solution with 5, 10, and 15% (v/v) TTO. The addition of TTO decreased MG-63 cell viability for both coating groups, but the Gel/TTO group showed higher cell viability. The antibacterial activity of the coated scaffolds was evaluated against S. aureus and higher inhibition of colony formation was found for Gel/TTO group. Therefore, the coating with Gel/TTO was effective in terms of antibacterial activity and cell viability. Such Gel/TTO coated ß-TCP/S53P4 BG scaffolds are proposed for antibacterial bone tissue engineering.


Asunto(s)
Aceite de Árbol de Té , Andamios del Tejido , Andamios del Tejido/química , Aceite de Árbol de Té/farmacología , Staphylococcus aureus , Ingeniería de Tejidos/métodos , Fosfatos de Calcio/farmacología , Fosfatos de Calcio/química , Antibacterianos/farmacología , Antibacterianos/química , Impresión Tridimensional
11.
Hig. aliment ; 36(295): e1089, Jul.-Dez. 2022. tab
Artículo en Portugués | VETINDEX | ID: biblio-1417944

RESUMEN

O amendoim (Arachis hypogaea L) é uma oleaginosa de grande importância econômica e nutricional, consumida in natura ou processada. Destaca-se, no estado de Sergipe, o amendoim cozido comercializado em supermercados, feiras, mercados e por ambulantes. Objetivou-se avaliar condições as higiênico-sanitárias de mercados municipais de Aracaju que comercializam amendoim cozido e analisar a qualidade microbiológica do amendoim. Participaram da pesquisa dois mercados de Aracaju, com dois comerciantes de amendoim em cada local. Para a avaliação das condições higiênico-sanitárias da banca de cada comerciante, foi aplicado um checklist com 27 itens referentes ao aspecto higiênico-sanitário do local de venda, higienização dos equipamentos, balcão e utensílios, e higiene do manipulador. Para as avaliações microbiológicas foram realizadas detecção de coliformes totais, coliformes termotolerantes, E. coli e Salmonella sp. em dois tipos de amendoim cozido (preparado pelo comerciante e adquirido pronto para a comercialização). Observou-se que todos os comerciantes apresentaram inconformidades, sendo classificados no Grupo 3 (estabelecimento de alto risco), de acordo com a legislação brasileira. As amostras de amendoim do Mercado 1 e 2 apresentaram conformidade com a legislação vigente. Entretanto, várias amostras do mercado 2 estavam com números elevados de coliformes totais e termotolerantes. Tornam-se necessárias ações educativas e corretivas em relação às boas práticas nos estabelecimentos estudados, bem como a realização de fiscalizações rotineiras com o propósito de melhorar as boas práticas de comercialização e contribuir para a segurança desse alimento.(AU)


Peanut (Arachis hypogaea L) is an oleaginous plant of great economic and nutritional importance, consumed fresh or processed. In the state of Sergipe, boiled peanuts are sold in supermarkets, fairs, markets and street vendors. The objective was to evaluate the hygienic-sanitary conditions of municipal markets in Aracaju that sell cooked peanuts and analyze the microbiological quality of the peanut. Two markets in Aracaju participated in the survey, with two peanut traders in each location. In order to assess the hygienic-sanitary conditions of each merchant's stand, a checklist with 27 items referring to the hygienic-sanitary aspect of the place of sale, cleaning of equipment, counter and utensils, and hygiene of the handler was applied. For microbiological evaluations, detection of total coliforms, thermotolerant coliforms, E. coli and Salmonella sp. in two types of cooked peanuts (prepared by the trader and purchased ready for sale). It was observed that all traders presented non-conformities being classified in Group 3 (high risk establishment), in accordance with Brazilian legislation. Peanut samples from Market 1 and 2 were in compliance with current legislation. However, several samples from market 2 had high numbers of total and thermotolerant coliforms. Educational and corrective actions are necessary in relation to good practices in the establishments studied, as well as routine inspections with the purpose of improving good marketing practices and contributing to the safety of this food.(AU)


Asunto(s)
Higiene Alimentaria , Técnicas Microbiológicas/métodos , Perfiles Sanitarios , Arachis , Brasil , Colimetría
12.
Sci. agric ; 79(2): e20200090, 2022. tab, ilus
Artículo en Inglés | VETINDEX | ID: biblio-1290181

RESUMEN

Short-term grazing behavior variables are sensitive to the canopy structure and have an impact on daily forage intake. This study evaluated the effect of pre- and post-grazing canopy heights on the forage harvesting process at a patch scale in a mixture of Brachiaria brizantha (Hochst. ex A. Rich.) Stapf. syn. Urochloa brizantha R.D. Webster cv. Marandu (palisade grass) and Arachis pintoi Krapov. & W.C. Greg. cv. Belomonte (forage peanut). Treatments were allocated to a split-plot arrangement in a completely randomized design. The plots, in their entirety, consisted of two pre-grazing canopy heights: 25 cm (CH25) and 35 cm (CH35); subplots consisted of three levels of defoliation severity: no defoliation (DS0); 20% depletion of pre-grazing canopy height (DS20); and 40% depletion of pre-grazing canopy height (DS40), with eight replications. Heifers were allowed to graze the patches (0.7 × 0.7 m) and their grazing behavior was recorded. Canopy structure measurements were taken both before and after grazing. Patches from CH35 presented greater stem mass for grass (p = 0.001) and legume (p = 0.002) than did patches from CH25. Bite rate, bite mass and instantaneous intake rate were greater for CH25 than for CH35 (p < 0.001, p = 0.068, and p = 0.074), and bite mass and instantaneous intake rate were lower for DS20 compared to DS0 (p = 0.032 and p = 0.016). Greater stem mass in the grazing strata negatively influenced the instantaneous intake rate.


Asunto(s)
Arachis , Pastizales/análisis , Brachiaria , Bovinos , Fabaceae
13.
Sci. agric. ; 79(2)2022.
Artículo en Inglés | VETINDEX | ID: vti-762539

RESUMEN

ABSTRACT: Short-term grazing behavior variables are sensitive to the canopy structure and have an impact on daily forage intake. This study evaluated the effect of pre- and post-grazing canopy heights on the forage harvesting process at a patch scale in a mixture of Brachiaria brizantha (Hochst. ex A. Rich.) Stapf. syn. Urochloa brizantha R.D. Webster cv. Marandu (palisade grass) and Arachis pintoi Krapov. & W.C. Greg. cv. Belomonte (forage peanut). Treatments were allocated to a split-plot arrangement in a completely randomized design. The plots, in their entirety, consisted of two pre-grazing canopy heights: 25 cm (CH25) and 35 cm (CH35); subplots consisted of three levels of defoliation severity: no defoliation (DS0); 20% depletion of pre-grazing canopy height (DS20); and 40% depletion of pre-grazing canopy height (DS40), with eight replications. Heifers were allowed to graze the patches (0.7 × 0.7 m) and their grazing behavior was recorded. Canopy structure measurements were taken both before and after grazing. Patches from CH35 presented greater stem mass for grass (p = 0.001) and legume (p = 0.002) than did patches from CH25. Bite rate, bite mass and instantaneous intake rate were greater for CH25 than for CH35 (p 0.001, p = 0.068, and p = 0.074), and bite mass and instantaneous intake rate were lower for DS20 compared to DS0 (p = 0.032 and p = 0.016). Greater stem mass in the grazing strata negatively influenced the instantaneous intake rate.

14.
Sci. agric ; 79(02): 1-10, 2022. ilus, tab, graf
Artículo en Inglés | VETINDEX | ID: biblio-1498024

RESUMEN

Short-term grazing behavior variables are sensitive to the canopy structure and have an impact on daily forage intake. This study evaluated the effect of pre- and post-grazing canopy heights on the forage harvesting process at a patch scale in a mixture of Brachiaria brizantha (Hochst. ex A. Rich.) Stapf. syn. Urochloa brizantha R.D. Webster cv. Marandu (palisade grass) and Arachis pintoi Krapov. & W.C. Greg. cv. Belomonte (forage peanut). Treatments were allocated to a split-plot arrangement in a completely randomized design. The plots, in their entirety, consisted of two pre-grazing canopy heights: 25 cm (CH25) and 35 cm (CH35); subplots consisted of three levels of defoliation severity: no defoliation (DS0); 20% depletion of pre-grazing canopy height (DS20); and 40% depletion of pre-grazing canopy height (DS40), with eight replications. Heifers were allowed to graze the patches (0.7 × 0.7 m) and their grazing behavior was recorded. Canopy structure measurements were taken both before and after grazing. Patches from CH35 presented greater stem mass for grass (p = 0.001) and legume (p = 0.002) than did patches from CH25. Bite rate, bite mass and instantaneous intake rate were greater for CH25 than for CH35 (p < 0.001, p = 0.068, and p = 0.074), and bite mass and instantaneous intake rate were lower for DS20 compared to DS0 (p = 0.032 and p = 0.016). Greater stem mass in the grazing strata negatively influenced the instantaneous intake rate.


Asunto(s)
Arachis/crecimiento & desarrollo , Brachiaria/crecimiento & desarrollo , Poaceae/crecimiento & desarrollo
15.
Biochimie ; 185: 96-104, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33746066

RESUMEN

Cancer cells exhibit an altered metabolic phenotype, consuming higher levels of the amino acid glutamine. This metabolic reprogramming depends on increased mitochondrial glutaminase activity to convert glutamine to glutamate, an essential precursor for bioenergetic and biosynthetic processes in cells. Mammals encode the kidney-type (GLS) and liver-type (GLS2) glutaminase isozymes. GLS is overexpressed in cancer and associated with enhanced malignancy. On the other hand, GLS2 is either a tumor suppressor or an oncogene, depending on the tumor type. The GLS structure and activation mechanism are well known, while the structural determinants for GLS2 activation remain elusive. Here, we describe the structure of the human glutaminase domain of GLS2, followed by the functional characterization of the residues critical for its activity. Increasing concentrations of GLS2 lead to tetramer stabilization, a process enhanced by phosphate. In GLS2, the so-called "lid loop" is in a rigid open conformation, which may be related to its higher affinity for phosphate and lower affinity for glutamine; hence, it has lower glutaminase activity than GLS. The lower affinity of GLS2 for glutamine is also related to its less electropositive catalytic site than GLS, as indicated by a Thr225Lys substitution within the catalytic site decreasing the GLS2 glutamine concentration corresponding to half-maximal velocity (K0.5). Finally, we show that the Lys253Ala substitution (corresponding to the Lys320Ala in the GLS "activation" loop, formerly known as the "gating" loop) renders a highly active protein in stable tetrameric form. We conclude that the "activation" loop, a known target for GLS inhibition, may also be a drug target for GLS2.


Asunto(s)
Activación Enzimática , Glutaminasa/química , Hígado/enzimología , Sustitución de Aminoácidos , Catálisis , Glutaminasa/genética , Glutaminasa/metabolismo , Humanos , Mutación Missense , Estructura Cuaternaria de Proteína , Relación Estructura-Actividad
16.
Semina ciênc. agrar ; 42(6): 3379-3398, nov.-dez. 2021. graf, tab
Artículo en Inglés | VETINDEX | ID: biblio-1370552

RESUMEN

Pasture-based systems are prevalent among small-scale family farms. Many farmers consider that the nutritional value of the plant is more relevant than the canopy structure. This study aimed to analyze the various factors related to plant structure and chemical composition that most influence milk yield per hectare under rotational stocking. The experiment was performed at the Animal Husbandry Experimental Station of the Extreme South of Bahia. Three rotational stocking systems with three forage species [Cynodon dactylon (L.) Pers. cv. Tifton 85, Urochloa brizantha (Hochst. ex A. Rich.) Stapf. cv. Xaraés, and Megathyrsus maximus Jacq. cv. Mombasa] were evaluated. Nine crossbred Holstein x Gyr cows were allocated to a balanced 3 x 3 Latin square design. The cows were rotated in three pastures every 14 days. The experimental period consisted of seven evaluation cycles of 42 days each. Cluster analysis, principal component analysis (PCA), and multivariate linear regression were the statistical techniques used to evaluate plant structure and morphological characteristics, and animal performance. Xaraés palisadegrass and Mombasa guinea grass were similar for all evaluated characteristics (P > 0.05), whereas Tifton 85 was different from them in terms of structural, morphological, and chemical composition characteristics (P < 0.05). In the PCA, 59.1% of the total variance was explained by components 1 and 2 for the structural and morphological characteristics, and forage chemical composition. Forage structural and morphological variables showed better results in the multivariate linear regression analysis for milk yield per hectare. Structural and morphological characteristics were more correlated with Mombasa guinea grass than Xaraés palisadegrass and Tifton 85. The structural and morphological characteristics of forages were the main factors determining milk yield per hectare in exclusively pasture-based systems with animals of low production.(AU)


Os sistemas baseados em pastagens são predominantes entre os pequenos agricultores familiares. Muitos agricultores consideram que o valor nutricional da planta é mais relevante que a estrutura do dossel. Este estudo teve como objetivo analisar os vários fatores relacionados à estrutura da planta e a composição química que mais influenciam a produção de leite por hectare sob lotação rotativa. O experimento foi realizado na Estação Experimental de Pecuária do Extremo Sul da Bahia. Três sistemas de lotação rotacionada com três espécies forrageiras [Cynodon dactylon (L.) Pers. cv. Tifton 85, Urochloa brizantha (Hochst. Ex A. Rich.) Stapf. cv. Xaraés e Megathyrsus maximus Jacq. cv. Mombaça] foram avaliados. Nove vacas mestiças Holandês x Gir foram distribuídas em um quadrado latino equilibrado 3 x 3. As vacas foram rotacionadas em três pastos a cada 14 dias. O período experimental consistiu de sete ciclos de avaliação de 42 dias cada. Análise de cluster, análise de componentes principais e regressão linear multivariada foram as técnicas estatísticas utilizadas para avaliar as características estruturais e morfológicas das plantas e o desempenho animal. O capim-Xaraés e o capim-Mombaça foram semelhantes para todas as características avaliadas (P > 0,05), enquanto o Tifton 85 foi diferente em termos de características estruturais, morfológicas e de composição química (P < 0,05). Na PCA, 59,1% da variância total foi explicada pelos componentes 1 e 2 para as características estruturais e morfológicas, e a composição química da forragem. As variáveis estruturais e morfológicas das forrageiras apresentaram melhores resultados na análise de regressão linear multivariada para a produção de leite por hectare. Características estruturais e morfológicas foram mais correlacionadas com o capim-Mombaça do que para os capins Xaraés e Tifton 85. As características estruturais e morfológicas das forragens foram o principal fator determinante da produção de leite por hectare em sistemas baseados exclusivamente à pasto com animais de baixa produção.(AU)


Asunto(s)
Pastizales , Brachiaria , Cynodon , Leche , Valor Nutritivo , Análisis de Regresión
17.
Biosci. j. (Online) ; 36(6): 2281-2287, 01-11-2020. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1148386

RESUMEN

Many therapies used for cancer (pathology whose cases are progressively increasing in the world) such as chemotherapy and radiotherapy have numerous adverse effects, with cardiotoxicity being one of the most important. This can be defined from the detection, by an imaging method, of a reduction of at least 10% in the left ventricular ejection fraction (LVEF), bringing it to a value below 53%. Anthracyclines (such as Doxorubicin), Trastuzumab, and Taxanes (Docetaxel) are among the most associated chemotherapeutics. To emphasize the importance of optimized treatment for heart failure and to review the main updates on the theme of cardiotoxicity. Case report and bibliographic review on the latest updates to the management of cardiotoxicity and associated heart failure. When correctly identifying the main risk factors associated with chemotherapy and the individual to develop myocardial injury, it is possible to perform the monitoring by means of two main predictors: the myocardial tension strength and the biomarkers. In this sense, changes associated with these predictors may allow early intervention through appropriate treatment and, with the advancement of research, even prevention, mainly using the association of Carvedilol with Enalapril. Continuous monitoring and early initiation of drug therapy for heart failure are clearly associated with a lower degree of myocardial injury and a lower rate of complications. In addition, there is still an increasingly promising possibility in relation to preventive drug therapy, however, there is still a lack of studies on this topic.


Muitas terapias utilizadas para o câncer (patologia cujos casos estão aumentando progressivamente no mundo) como a quimioterapia e a radioterapia possuem inúmeros efeitos adversos, sendo a cardiotoxicidade um dos mais importantes. Esta pode ser definida a partir da detecção, por um método de imagem, de uma redução de, pelo menos, 10% na fração de ejeção do ventrículo esquerdo (FEVE), levando a mesma para um valor inferior a 53%. As Antraciclinas (como a Doxorrubicina), o Trastuzumab, e os Taxanos (Docetaxel) estão entre os quimioterápicos mais associados. Enfatizar a importância do tratamento otimizado para insuficiência cardíaca e revisar sobre as principais atualizações do tema cardiotoxicidade. Relato de caso e revisão bibliográfica sobre últimas atualizações de condutas referentes ao manejo da cardiotoxicidade e insuficiência cardíaca associada. Ao se identificar corretamente os principais fatores de risco associados à quimioterapia e ao indivíduo para desenvolver a injúria miocárdica, é possível realizar o monitoramento por meio de dois preditores principais: a força de tensão miocárdica e os biomarcadores. Nesse sentido, alterações associadas a esses preditores podem permitir a intervenção precoce por meio do tratamento adequado e, com o avanço das pesquisas, até mesmo a realização da prevenção, principalmente utilizando-se a associação de Carvedilol com Enalapril. Monitorização contínua e início precoce da terapia medicamentosa para insuficiência cardíaca estão claramente associadas com um menor grau de injúria miocárdica e um menor índice de complicações. Além disso, ainda há a possibilidade cada vez mais promissora em relação à terapia medicamentosa preventiva, porém, ainda há carência de estudos em relação a este tema.


Asunto(s)
Preparaciones Farmacéuticas , Biomarcadores , Cardiotoxicidad , Insuficiencia Cardíaca
18.
Sci Rep ; 10(1): 13026, 2020 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-32747801

RESUMEN

Prader-Willi (PWS) and Angelman (AS) syndromes are two clinically distinct imprinted disorders characterized by genetic abnormalities at 15q11-q13. Early diagnosis of both syndromes provides improved treatment and accurate genetic counseling. Whole blood (WB) is the most common DNA source of many methodologies to detect PWS and AS, however, the need of WB makes a massive screening difficult in newborns due to economic and technical limitations. The aim of this study was to adapt a Methylation-sensitive High-Resolution Melting (MS-HRM) approach from dried blood spot (DBS) samples, assessing the different DNA isolation techniques and diagnostic performance. Over a 1-year period, we collected 125 DBS cards, of which 45 had already been diagnosed by MS-HRM (20 PWS, 1 AS, and 24 healthy individuals). We tested three different DBS-DNA extraction techniques assessing the DNA concentration and quality, followed by MS-HRM and statistical comparison. Each DBS-DNA extraction method was capable of accuracy in detecting all PWS and AS individuals. However, the efficiency to detect healthy individuals varied according to methodology. In our experience, DNA extracted from DBS analyzed by the MS-HRM methodology provides an accurate approach for genetic screening of imprinting related disorders in newborns, offering several benefits compared to traditional whole blood methods.


Asunto(s)
Síndrome de Angelman/sangre , Síndrome de Angelman/genética , Metilación de ADN/genética , Pruebas con Sangre Seca , Tamizaje Neonatal , Desnaturalización de Ácido Nucleico/genética , Síndrome de Prader-Willi/sangre , Síndrome de Prader-Willi/genética , Autoantígenos/genética , Humanos , Recién Nacido , Proyectos Piloto , Ribonucleasa P/genética
19.
Ecotoxicol Environ Saf ; 202: 110895, 2020 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-32615496

RESUMEN

Halogenated phenols, such as 2,4-dichlorophenol (2,4-DCP) and 4-bromophenol (4-BP) are pollutants generated by a various industrial sectors like chemical, dye, paper bleaching, pharmaceuticals or in an agriculture as pesticides. The use of Horseradish peroxidase (HRP) in the halogenated phenols treatment has already been mentioned, but it is not well understood how the different phenolic substrates can bind in the peroxidase active site nor how these specific interactions can influence in the bioremediation potential. In this work, different removal efficiencies were obtained for phenolic compounds investigated using HRP as catalyst (93.87 and 59.19% to 4BP and 2,4 DCP, respectively). Thus, to rationalize this result based on the interactions of phenols with active center of HRP, we combine computational and experimental methodologies. The theoretical approaches utilized include density functional theory (DFT) calculations, docking simulation and quantum mechanics/molecular mechanics (QM/MM) technique. Michaelis Menten constant (Km) obtained through experimental methodologies were 2.3 and 0.95 mM to 2,4-DCP and 4-BP, respectively, while the specificity constant (Kcat/Km) found was 1.44 mM-1 s-1 and 0.62 mM-1 s-1 for 4-BP and 2,4-DCP, respectively. The experimental parameters appointed to the highest affinity of HRP to 4-BP. According to the molecular docking calculations, both ligands have shown stabilizing intermolecular interaction energies within the HRP active site, however, the 4-BP showed more stabilizing interaction energy (-53.00 kcal mol-1) than 2,4-dichlorophenol (-49.23 kcal mol-1). Besides that, oxidative mechanism of 4-BP and 2,4-DCP was investigated by the hybrid QM/MM approach. This study showed that the lowest activation energy values for transition states investigated were obtained for 4-BP. Therefore, by theoretical approach, the compound 4-BP showed the more stabilizing interaction and activation energy values related to the interaction within the enzyme and the oxidative reaction mechanism, respectively, which corroborates with experimental parameters obtained. The combination between experimental and theoretical approaches was essential to understand how the degradation potential of the HRP enzyme depends on the interactions between substrate and the active center cavity of the enzyme.


Asunto(s)
Biodegradación Ambiental , Peroxidasas/metabolismo , Fenoles/metabolismo , Catálisis , Contaminantes Ambientales , Peroxidasa de Rábano Silvestre/química , Cinética , Simulación del Acoplamiento Molecular , Oxidación-Reducción
20.
Artículo en Inglés | MEDLINE | ID: mdl-32547626

RESUMEN

BACKGROUND: Ultrasound (US) in psoriasis (PsO) and psoriatic arthritis (PsA) is an important tool in several situations to detect joint ecostructural damage as well as other tissue alterations, such as those that occur in the larger vessels. The objective of this study was to detect and correlate the changes that indicate the inflammatory and atherosclerotic process in two groups of patients, using nail US and carotid artery intima-media thickness radiofrequency (RF) software. METHODS: A total of 30 patients diagnosed with (PsO) and (PsA) were selected. About 15 patients were present in each group, assigned by the Dermatology and Rheumatology Service of the Universidade Pontifícia Católica de Campinas, São Paulo, Brazil, and were assessed using carotid artery US (radiofrequency quality intima-media thickness [RF-QIMT]), joint US, clinical evaluation, and laboratory tests. RESULTS: Spearman and Pearson correlations between US variables per group were Psoriasis Area and Severity Index (PASI) and loss of the nail pattern trilaminar: r=0.658, p=0.015; Framingham Score (FS) and Internal Resistance Index (IR): 0.351 to 0.526, p=0.034 to 0.002; the significant correlations by the Bayesian factor (BF) were those with a BF greater than 2.5, between QIMT expected with FS: r=0.677, BF=10.06, with total cholesterol: r=0.5232, BF=2.60, and QIMT-RF with low density lipoproteins: r=0.633, BF=3.70. CONCLUSION: The use of US in the evaluation of these patients showed significant correlations between clinical and laboratory measures, characterized by QIMT and FS as well as changes in nail insertion. Future studies may demonstrate an even better interaction.

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