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1.
J Theor Biol ; 590: 111853, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-38768893

RESUMO

Fungal pellets are hierarchical systems that can be found in an ample variety of applications. Modeling transport phenomena in this type of systems is a challenging but necessary task to provide knowledge-based processes that improve the outcome of their biotechnological applications. In this work, an upscaled model for total mass and momentum transport in fungal pellets is implemented and analyzed, using elements of the volume averaging and adjoint homogenization methods departing from the governing equations at the microscale in the intracellular and extracellular phases. The biomass is assumed to be composed of a non-Newtonian fluid and the organelles impervious to momentum transport are modeled as a rigid solid phase. The upscaled equations contain effective-medium coefficients, which are predicted from the solution of adjoint closure problems in a three-dimensional periodic domains representative of the microstructure. The construction of these domains was performed for Laccaria trichodermophora based on observations of actual biological structures. The upscaled model was validated with direct numerical simulations in homogeneous portions of the pellets core. It is shown that no significant differences are observed when the dolipores are open or closed to fluid flow. By comparing the predictions of the average velocity in the extracellular phase resulting from the upscaled model with those from the classical Darcy equation (i.e., assuming that the biomass is a solid phase) the contribution of the intracellular fluid phase was evidenced. This work sets the foundations for further studies dedicated to transport phenomena in this type of systems.


Assuntos
Modelos Biológicos , Biomassa , Simulação por Computador
2.
Environ Res ; 258: 119477, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38909943

RESUMO

In this study, UiO-67 (Zr)/g-C3N4 composites (U67N) were synthesized at wt.% ratios of 05:95, 15:85, and 30:70 using the solvothermal method at 80 °C for 24 h followed by calcination at 350 °C. The composites were characterized using UV-Vis diffuse reflectance spectroscopy, Fourier-transform infrared spectroscopy, photoluminescence spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction, scanning electron microscopy-energy-dispersive X-ray spectroscopy, transmission electron microscopy, and nitrogen physisorption analysis. In addition, thermal stability analysis of UiO-67 was conducted using thermogravimetric analysis. The photocatalytic performance of the composites was assessed during the degradation and mineralization of a mixture of methylparaben (MeP) and propylparaben (PrP) under simulated sunlight. The adsorption process of U67N 15:85 was characterized through kinetic studies and adsorption capacity experiments, which were modeled using pseudo-first-order and pseudo-second-order kinetics and Langmuir and Freundlich isotherms, respectively. The influence of pH levels 3, 5, and 7 on the photocatalytic degradation of the mixture was investigated, revealing enhanced degradation and mineralization at pH 3. The U67N composite exhibited dual capability in removing contaminants through adsorption and photocatalytic processes. Among the prepared composites, U67N 15:85 demonstrated the highest photocatalytic activity, achieving removal efficiencies of 96.8% for MeP, 92.5% for PrP, and 45.7% for total organic carbon in 300 kJ/m2 accumulated energy (3 h of reaction time). The detoxification of the effluent was confirmed through acute toxicity evaluation using the Vibrio fischeri method. The oxidation mechanism of the heterojunction formed between UiO-67 (Zr) and g-C3N4 was proposed based on PL analysis, photoelectrochemistry studies (including photocurrent response, Nyquist, and Mott-Schottky analyses), and scavenger assays.

3.
Int J Biometeorol ; 68(3): 427-434, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38147120

RESUMO

The aim of this study was to determine effects of parity (primiparous vs. multiparous), seasonal heat stress at calving (summer vs. winter), and time postpartum on some parameters associated with colostrum quality in Holstein cows reared in the Sonoran Desert ecosystem. Forty-seven cows (11 primiparous and 36 multiparous) expected to calve during summer, and 46 cows during winter (14 primiparous and 32 multiparous) were randomly selected. Management and feeding before and after parturition were similar for cows in both seasons. After parturition, colostrum from all cows was evaluated for volume, weight, temperature, density, and content of fat, protein, solids non-fat (SNF), and immunoglobulins (IGG). Data were analyzed with a model that included effects of parity status, calving season, and time postpartum, as well as all interactions. Colostrum produced in summer was warmer (P < 0.01) by almost 6 °C than winter colostrum, while colostrum from multiparous was warmer (P = 0.02) by 1.2 °C than that produced by primiparous cows. Colostrum volume and weight were not impacted by parity, calving season or time postpartum. Density, protein, and SNF content in colostrum were higher (P < 0.01) in multiparous vs. primiparous cows, as well as at parturition (0 h postpartum) than at 12 h postpartum (P < 0.01). At calving (0 h), spring colostrum had higher fat content (P < 0.01) and lower (P < 0.01) IGG concentration than that collected in summer, and no difference (P > 0.05) between seasons was observed for these components at 12 h postpartum. Multiparous cows produced colostrum with higher (P < 0.01) IGG concentrations than primiparous cows. In conclusion, only 0-h colostrum and that from multiparous cows was categorized as "Excellent," meanwhile the colostrum produced under summer heat stress was characterized as "Good" with reduced fat content. While the lacteal secretion collected at 12 post-partum still classified as colostrum, substantially lower contents of IGG, protein, fat, and SNF decreased its classification to "Poor" from the classification of "Excellent" at 0 h postpartum.


Assuntos
Colostro , Lactação , Gravidez , Feminino , Humanos , Bovinos , Animais , Estações do Ano , Leite , Ecossistema , Período Pós-Parto , Imunoglobulina G
4.
Clin Exp Immunol ; 211(3): 269-279, 2023 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-36622786

RESUMO

Cohorts of healthy younger adults (18-50yrs) and healthy older adults (60-75yrs) were immunized intramuscularly or intranasally with an adenovirus-vectored RSV vaccine (PanAd3-RSV) as a prime dose and boosted with PanAd3-RSV or a poxvirus-vectored vaccine (MVA-RSV) encoding the same insert. Whole blood gene expression was measured at baseline, 3- and 7-days post vaccination. Intramuscular prime vaccination with PanAd3-RSV induced differential expression of 643 genes (DEGs, FDR < 0.05). Intranasal prime vaccination with PanAd3-RSV did not induce any differentially expressed genes (DEGs) in blood samples at 3 days post vaccination. Intranasally primed participants showed greater numbers of DEGS on boosting than intramuscularly primed participants. The most highly enriched biological processes related to DEGs after both prime and boost vaccination were type-1 interferon related pathways, lymphocytic and humoral immune responses.


Assuntos
Pan troglodytes , Transcriptoma , Animais , Humanos , Idoso , Pan troglodytes/genética , Imunização Secundária , Vetores Genéticos/genética , Adenoviridae/genética , Anticorpos Antivirais
5.
Trop Anim Health Prod ; 55(3): 183, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37129708

RESUMO

Two hundred Holstein heifers were divided by hair coat color in black (n1 = 60), white (n2 = 62), and mixed (n3 = 78) to accomplish two objectives: (1) to compare physiological variables using an analysis of variance, and (2) to construct regression equations to predict rectal temperature. In each heifer, rectal temperature (RT), respiration frequency (RF), and body surface temperatures (obtained with infrared thermography in eye, nose, forehead, head, neck, ear, shoulder, flank, belly, leg, loin, rump, and vulva) were measured. Black heifers had more RF and RT (P < 0.01) than mixed and white coat heifers; white heifers had similar RT than mixed color heifers, but they exhibited less RF (P < 0.05). In general, black and mixed coat color heifers had higher BST (P < 0.01) than white heifers in the majority of the anatomical regions measured. For black coat heifers, the best regression model to predict RT included three predictor variables: [RT = 35.59 - 0.013 (RH) + 0.045 (RF) + 0.019 (TEar); R2 = 71%]. For white coat heifers, the best model included two predictor variables: [RT = 35.29 + 0.035 (RF) + 0.033 (TForehead); R2 = 71%]; and for mixed coat color heifers, the best model included two predictor variables: [RT = 35.07 + 0.022 (RF) + 0.038 (THead); R2 = 44%]. Heifers with dark hair coat color showed higher physiological constants than white heifers; the prediction of rectal temperature was more precise in heifers with well-defined hair coat color. Physiological and climatic variables, along with infrared thermography, represent an appropriate combination to predict rectal temperature in Holstein heifers with predominant white or black hair coat color.


Assuntos
Temperatura Corporal , Clima Desértico , Animais , Bovinos , Feminino , Temperatura , Termografia/veterinária , Nariz
6.
Ann Hepatol ; 27(6): 100767, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36223880

RESUMO

INTRODUCTION AND OBJECTIVES: Obesity is a global health problem that triggers fat liver accumulation. The prevalence of obesity and the risk of non-alcoholic steatohepatitis (NASH) among young obese Mexican is high. Furthermore, genetic predisposition is a key factor in weight gain and disrupts metabolism. Herein, we used Whole-Exome Sequencing to identify potential causal variants and the biological processes that lead to obesity with progression to NASH among Mexican patients. MATERIALS AND METHODS: Whole-Exome Sequencing was performed in nine obese patients with NASH diagnosis with a BMI ≥30 kg/m2 and one control (BMI=24.2 kg/m2) by using the Ion S5TM platform. Genetic variants were determined by Ion Reporter software. Enriched GO biological set genes were identified by the WebGestalt tool. Genetic variants within ≥2 obese NASH patients and having scores of SIFT 0.0-0.05 and Polyphen 0.85-1.0 were categorized as pathogenic. RESULTS: A total of 1359 variants with a probable pathogenic effect were determined in obese patients with NASH diagnosis. After several filtering steps, the most frequent pathogenic variants found were rs25640-HSD17B4, rs8105737-OR1I1, rs998544-OR5R1, and rs4916685, rs10037067, and rs2366926 in ADGRV1. Notably, the primary biological processes affected by these pathogenic variants were the sensory perception and detection of chemical stimulus pathways in which the olfactory receptor gene family was the most enriched. CONCLUSIONS: Variants in the olfactory receptor genes were highly enriched in Mexican obese patients that progress to NASH and could be potential targets of association studies.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Receptores Odorantes , Humanos , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Hepatopatia Gordurosa não Alcoólica/genética , Receptores Odorantes/genética , Receptores Odorantes/metabolismo , Sequenciamento do Exoma , Fígado/patologia , Obesidade/diagnóstico , Obesidade/epidemiologia , Obesidade/genética
7.
Int J Biometeorol ; 65(8): 1451-1459, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33742264

RESUMO

The aim of this study was to evaluate the effect of seasonal heat stress (HS) on productive performance, physiological responses, metabolism, and hematological profile of hair breed male lambs finished in feedlot. Twenty Dorper × Katahdin male lambs (body weight = 34.6 ± 1.4 kg and age = 4.5 months) were housed in individual pens and exposed to environmental conditions of summer HS (n = 10, temperature = 28.3 ± 4.0 °C and THI = 77.2 ± 5.4 units) or winter thermoneutrality (n = 10, temperature = 19.2 ± 2.6 °C and THI = 64.0 ± 3.0 units). Each season, a 30-day feeding test was conducted to measure study variables. Compared to thermoneutral lambs, heat-stressed lambs had lower (P < 0.01) growth rate and feed efficiency without changing dry matter intake. Heat-stressed lambs presented higher (P < 0.01) rectal temperature and respiratory rate through the daytime than termoneutral lambs. On most sampling days, summer HS caused lower (P < 0.01) serum concentrations of glucose, cholesterol, total protein, urea, potassium, and thyroid hormones, but higher (P < 0.01) serum triglyceride and chlorine values. Overall serum concentrations of cortisol and insulin were unaffected by summer HS. The blood of heat-stressed lambs showed lower (P ≤ 0.03) erythrocyte and platelet counts, hemoglobin, and hematocrit, but higher (P ≤ 0.03) erythrocyte size and leucocyte count than the blood of thermoneutral lambs. In conclusion, hair breed male lambs in response to chronic conditions of summer HS had slow growth but avoided hyperthermia due to the activation of physiological, metabolic and endocrine adjustments.


Assuntos
Transtornos de Estresse por Calor , Animais , Composição Corporal , Peso Corporal , Colesterol , Transtornos de Estresse por Calor/veterinária , Resposta ao Choque Térmico , Temperatura Alta , Masculino , Ovinos , Estresse Fisiológico
8.
Rhinology ; 59(2): 191-204, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33346253

RESUMO

OBJECTIVE: The endoscopic endonasal approach (EEA) has been proposed as an alternative in the surgical removal of ventral brainstem lesions. However, the feasibility and limitations of this approach to treat such pathologies are still poorly understood. This study aimed to report our experience in five consecutive cases of intrinsic brainstem lesions that were managed via an EEA, as well as the specific anatomy of each case. METHODS: All patients were treated in a single center by a multidisciplinary surgical team between 2015 and 2019. Before surgery, a dedicated anatomical analysis of the brainstem safe entry zone was performed, and proper surgical planning was carried out. Neurophysiological monitoring was used in all cases. Anatomical dissections were performed in three human cadaveric heads using 0° and 30° endoscopes, and specific 3D reconstructions were executed using Amira 3D software. RESULTS: All lesions were located at the level of the ventral brainstem. Specifically, one mesencephalic cavernoma, two pontine ca- vernomas, one pontine gliomas, and one medullary diffuse midline glioma were reported. Cerebrospinal fluid leak was the major complication that occurred in one case (medullary diffuse midline glioma). From an anatomical standpoint, three main safe entry zones were used, namely the anterior mesencephalic zone (AMZ), the peritrigeminal zone (PTZ, used in two cases), and the olivar zone (OZ). Reviewing the literature, 17 cases of various brainstem lesions treated using an EEA were found. CONCLUSIONS: To our knowledge, this was the first preliminary clinical series of intrinsic brainstem lesions treated via an EEA presented in the literature. The EEA can be considered a valid surgical alternative to traditional transcranial approaches to treat selected intra-axial brainstem lesions located at the level of the ventral brainstem. To achieve good results, surgery must involve comprehensive anatomical knowledge, meticulous preoperative surgical planning, and intraoperative neurophysiological moni- toring.


Assuntos
Tronco Encefálico , Endoscopia , Tronco Encefálico/cirurgia , Humanos , Nariz/cirurgia
9.
Trop Anim Health Prod ; 53(5): 504, 2021 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-34622357

RESUMO

This study aimed to determine whether cows detected as tuberculosis (bTB) reactors and seropositive to brucellosis (bBR), as well as co-positive to bBR and bTB (bBR-bTB) and with a complete lactation before slaughter, were associated with reduced milk production and fertility. A total of 8068 productive and reproductive records of high-yielding Holstein cows from a single large dairy herd with a high prevalence of bTB and bBR were collected from 2012 to 2015. Lactation derived either from calving (n = 6019) or hormonally induced lactation (n = 2049), and all cows received growth hormone throughout lactation. For cows not induced into lactation, pregnancy rate to first service for healthy cows (C; 26.6%) was higher (P < 0.01) than bBR (15.2%), bTB (15.8%), and bBR-bTB (1.3%) cows. For induced cows, pregnancy rate to first service did not differ significantly among C, bBR, and bTB (14.5-17.3%) cows, but the percentage success of first service was extremely low (1.3%; P < 0.01) in bBR-bTB cows. Services per pregnancy (only pregnant cows) were lowest for C (3.3 ± 2.9; P < 0.01) and highest (6.4 ± 3.4) for bBR-bTB non-induced cows. This variable was lowest for C (2.9 ± 2.5; P < 0.01) and highest for bBR-bTB non-induced cows (6.3 ± 3.1). Pregnancy rate to all services did not differed for C (79.5%), bBR (76.7%), and bTB (75.9%) but was lower (58.9%; P < 0.01) for bBR-bTB non-induced cows. For induced cows this variable was highest for bBR (53.3%) and lowest for bBR-bTB (34.1%; P < 0.01) non-induced cows. 305-d milk production was increased by 4%, and total milk yield by 7% in TB-positive cows compared to that of the negative cows non-induced hormonally into lactation. This study showed the negative impact of the co-positivity for bTB and bBR on the reproductive efficiency of Holstein cows, although positive bTB and bBR tests enhanced milk yield.


Assuntos
Brucelose Bovina/diagnóstico , Doenças dos Bovinos , Fertilidade , Leite , Tuberculose Bovina/diagnóstico , Animais , Bovinos , Doenças dos Bovinos/diagnóstico , Feminino , Lactação , Gravidez
10.
Trop Anim Health Prod ; 53(1): 141, 2021 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-33496863

RESUMO

A total of 1338 high-yielding cows with five lactations from a large well-managed commercial dairy operation in a hot environment of northern Mexico were used to evaluate milk yield and reproductive performance of cows undergoing unplanned extended lactations (EL; > 450 days). The null hypothesis that cumulative milk yield during five consecutive lactations is the same in cows not having unplanned EL and cows with several EL was tested. All EL resulted from cows failing to become pregnant with ≥ 4 services. Cows were allocated to 1 of 6 groups according to the number of EL (EL0 for cows with no EL to EL5 for cows with 5 EL). Cumulative milk yield was highest (P < 0.01) for EL5 cows (95,499 kg) and lowest for EL0 cows (56,236 kg). Likewise, cumulative days in milk were greatest (P < 0.01) in EL5 (2968 days) and lowest in EL0 (1857 days) cows. Mean milk yield per lactation increased linearly with the increase in the number of extended lactations with a maximum of 19,099 kg of milk/lactation for EL5 cows. Mean daily milk yield/productive life was lowest (P < 0.01) for EL0 (30.2 kg) and highest for EL5 (32.1 kg). The percentage of days in milk relative to days from birth to the end of the fifth lactation was highest for EL5 (78.1%) and lowest for EL0 (59.6%), with EL2 to EL4 cows intermediate. Length of calving interval was longest (P < 0.01) for EL5 (24.7 months) and shortest for EL0 (15.5 months) cows. It was concluded that it is worthwhile maintaining high-yielding cows incapable to conceive before 230 days in milk because they did conceive again and produced considerable amounts of milk during their productive life, which substantially prolonged their permanence time in the herd.


Assuntos
Lactação , Leite , Animais , Bovinos , Feminino , México , Parto , Gravidez , Reprodução
11.
Am J Physiol Regul Integr Comp Physiol ; 318(2): R338-R350, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31850818

RESUMO

Exposure to different stressors in utero is linked to adult diseases such as obesity and hypertension. In this study, the impact of prenatal infection (PNI) on adult body weight and cardiovascular function was evaluated using a naturally occurring rodent pathogen, Mycoplasma pulmonis (MP). Pregnant Sprague-Dawley rats were infected with MP on gestationalday 14 and gave birth naturally. Adult PNI offspring weighed more than controls, but resting mean arterial pressure (MAP) was unchanged. Subcutaneous injection of angiotensin II (10 µg/kg) elicited a rise in MAP that was greater in both male and female PNI offspring compared with controls (P < 0.03). The accompanying reflex bradycardia was similar to the controls, suggesting that PNI induced baroreflex dysfunction. Subcutaneous nicotine administration, a potent cardiorespiratory stimulus, also elicited a transient rise in MAP that was generally greater in the PNI group, but the change in MAP from baseline was only significant in the PNI females compared with controls (P < 0.03). Elevated body weight and cardiovascular reactivity in the PNI offspring was associated with an increase in the ratio of hypothalamic corticotrophin-releasing hormone receptors type 1 to type 2 gene expression in both sexes compared with controls. These findings support previous studies demonstrating that PNI induces alterations in cardiovascular function and body weight. Yet, unlike previous studies utilizing other models of PNI (e.g., endotoxin), MP PNI did not induce resting hypertension. Thus, our study provides a foundation for future studies evaluating the cardiovascular risks of offspring exposed to microbial challenges in utero.


Assuntos
Angiotensina II/administração & dosagem , Pressão Arterial/efeitos dos fármacos , Barorreflexo/efeitos dos fármacos , Doenças Cardiovasculares/etiologia , Infecções por Mycoplasma/complicações , Mycoplasma pulmonis/patogenicidade , Efeitos Tardios da Exposição Pré-Natal , Fatores Etários , Animais , Doenças Cardiovasculares/metabolismo , Doenças Cardiovasculares/fisiopatologia , Modelos Animais de Doenças , Feminino , Idade Gestacional , Hipotálamo/metabolismo , Hipotálamo/fisiopatologia , Injeções Subcutâneas , Masculino , Infecções por Mycoplasma/microbiologia , Gravidez , Ratos Sprague-Dawley , Receptores de Hormônio Liberador da Corticotropina/genética , Receptores de Hormônio Liberador da Corticotropina/metabolismo , Aumento de Peso
12.
Mol Phylogenet Evol ; 133: 176-188, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30639765

RESUMO

The genus Agave sensu lato contains ca. 211 described species, many of which are considered keystone species because of their ecological dominance and the quantity of resources they provide with their massive, nectar-rich inflorescences. The large diversity of Agave species has been hypothesized as being related to their reproductive strategy (predominantly monocarpic) and diverse pollinators (e.g., bats, hummingbirds, hawkmoths). In particular, Agave species provide resources that a few genera of nectar feeding bats from the subfamily Glosophaginae are dependent upon. To explore a possible coevolutionary relationship between Agave and the bat species that pollinate them, we calibrated molecular phylogenies of both groups and looked for a correlation in their dates of divergence. One coding and two non-coding regions of the chloroplast genome were sequenced from 49 species of the Agavoideae (Asparagaceae), and the mitochondrial gene Cyt-b and nuclear coding gene RAG2 were either sequenced or obtained from gene bank for 120 Phyllostomid bats. Results from the analyses indicate that Agave sensu lato is a young genus (estimated crown age 2.7-8.5/stem age 4.6-12.3 Ma), with an increasing diversification rate, and the highest speciation rate among Agavoideae's clades. The origin of the Glossophaginae bats (stem age 20.3-23.5 Ma) occurred prior to the stem age of Agave sensu lato, while the origin of the current pollinators of Agave species, members of the genera Glossophaga, Leptonycteris, Anoura, Choeronyscus, Musonycteris and Choeronycteris, was estimated to be around 6.3-16.2 Ma, overlapping with the stem age of Agave sensu lato, supporting the hypothesis of diffuse coevolution.


Assuntos
Agave/parasitologia , Evolução Biológica , Quirópteros/fisiologia , Polinização , Animais , Sequência de Bases , Teorema de Bayes , Quirópteros/classificação , Filogenia , Fatores de Tempo
13.
J Therm Biol ; 81: 82-88, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30975427

RESUMO

Vulnerable animals to heat stress have been described as ones with dark or black hides due to increasing absorption of solar radiation. The effect of coat color in pluriparous contemporary Holstein cows in a hot environment (mean annual temperature 24.6 °C), on body surface temperature (infrared thermography), physiological and hematological variables as well as milk yield and reproductive performance was assessed using 178 Holstein pluriparous cows (74 predominantly white and 104 predominantly black). Data were collected in the morning and afternoon in July (mean temperature-humidity index 82 units). Body condition score at mid-lactation (128 ±â€¯32 days in milk at the start of the experiment) was higher (P < 0.01) in predominantly white than in black cows (3.3 vs. 3.2). Respiration rate did not differ between groups (72 ±â€¯23 vs. 73 ±â€¯20 breaths/min for white and black cows, respectively, sampling time combined). In contrast, rectal temperature of black cows was 0.1 °C higher (P ≤ 0.01) than white cows, regardless of sampling time. The only significant hematologic change was a slight increase in mean corpuscular volume in black cows (54.7 fL, P < 0.01) compared to white cows (53.8 fL), but it remained within the reference range. Differences due to coat color did not alter body surface temperatures at any time of the day. Conception rates, services per conception, calving intervals and fetal losses were not associated with hair coat color, but cows with predominantly white coat produced 394 kg more (P < 0.01) fat-corrected milk in 305 days compared to cows with predominantly black coat. It was concluded that in this hot-arid environment with cows housed in facilities with extensive cooling, black hair coat moderately reduces 305-d milk yield without affecting milk composition, body surface temperature, and reproductive performance.


Assuntos
Temperatura Corporal , Bovinos/fisiologia , Cor de Cabelo/fisiologia , Resposta ao Choque Térmico , Leite/metabolismo , Reprodução , Animais , Feminino , Fertilização , Temperatura Alta , Lactação , Leite/química , Paridade , Gravidez
14.
J Therm Biol ; 82: 142-149, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31128641

RESUMO

The main cause of death in newborn lambs is hypothermia, so is necessary to identify the factors affecting variations in body surface temperatures of sheep neonates because approximately 60% of their body heat losses occur through the skin. This study aimed to establish relationships among body surface thermography from different regions with rectal temperature (RT), birth weight (BW) and climatic variables in hair breed newborn lambs during early spring in an arid region. Data of body surface temperatures measured by infrared thermography (entire head, eye, muzzle, ear, entire body, shoulder, rump, loin, right flank, belly and leg), RT and BW were collected at 0, 12 and 24 h post-lambing in 85 lambs born in early spring. Relative humidity [RH], temperature [Te] and temperature-humidity index [THI] were also recorded. RT was not correlated with surface temperatures at 0 and 24 h, but it was at 12 h with all of them (0.36 ≤ r ≤ 0.44). BW and some surface temperatures were negatively correlated at 0 and 24 h (-0.24 ≤ r ≤ -0.30), but positively at 12 h (0.25 ≤ r ≤ 0.27). All surface temperatures were positively correlated (0.51 ≤ r ≤ 0.85) with Te and THI in the three sampling times. Principal component (PC) analysis showed that PC1 explained the majority of the variance (71-72%), followed by PC2 (8-9%) at 0, 12 and 24 h. Body surface temperatures increased as Te and THI also increased, but decreased with the increase in HR. In conclusion, under early spring environment (predominantly cold), the variations in body surface temperatures of hair sheep neonates were more closely related to climatic variables than to RT and BW. Thermography proved to be an effective tool to determine body heat loss by radiation in skin of neonate lambs.


Assuntos
Carneiro Doméstico/fisiologia , Termografia/veterinária , Animais , Animais Recém-Nascidos , Peso ao Nascer , Temperatura Corporal , Regulação da Temperatura Corporal , Clima
15.
Trop Anim Health Prod ; 50(7): 1611-1616, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29717378

RESUMO

The aims of the present study were to investigate (1) the risk factors that influence the occurrence of clinical ketosis (CK; blood ß-hydroxybutyrate > 3.0 mmol/L) and (2) to determine the influence of subclinical ketosis (SCK; 1.2 ≤ ß-hydroxybutyrate ≤ 2.9 mmol/L) and CK on reproductive performance and milk yield in high-yielding Holstein cows in a hot environment. Cows (n = 345) were blood sampled from 6 to 15 days postpartum for ß-hydroxybutyrate (BHB) determination with a hand-held meter. Cows calving in spring had 3.7 increased odds of having CK (20.7% incidence) than cows calving in summer (3.9% incidence) and autumn (9.4% incidence). Temperature-humidity index < 83 was associated with 1.6 times higher risk for CK compared with cows calving in warmer days. First-service conception rate was 12 and 16 percentage point higher (P < 0.05) in nonketotic cows compared with cows with SCK and CK, respectively. Actual 305-day milk yields for healthy, SCK, and CK cows were 9991 ± 1411, 10,123 ± 1442, and 10,386 ± 1435 kg (mean ± SD), respectively, with no difference (P > 0.05) between groups. In conclusion, this study documented that ketosis was seasonal with lower incidence of this metabolic disease during hot seasons and with increased ambient temperature at calving. Also, 305-day milk yield of Holstein cows was not related to blood BHB content early in lactation in this hot environment. However, elevated circulating BHB was negatively associated with conception rate at first service and fetal losses.


Assuntos
Doenças dos Bovinos/epidemiologia , Bovinos , Indústria de Laticínios/métodos , Cetose/epidemiologia , Leite/metabolismo , Ácido 3-Hidroxibutírico/sangue , Animais , Doenças dos Bovinos/metabolismo , Clima , Feminino , Fertilização , Temperatura Alta , Incidência , Cetose/veterinária , Lactação , Período Pós-Parto , Reprodução , Fatores de Risco , Estações do Ano
16.
Eur J Neurosci ; 46(3): 1875-1886, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28661071

RESUMO

Travelling across several time zones requires a fast adjustment of the circadian system and the differential adjustment speeds of organs and systems results in what is commonly referred as jet lag. During this transitory state of circadian disruption, individuals feel discomfort, appetite loss, fatigue, disturbed sleep and deficient performance of multiple tasks. We have demonstrated that after a 6-h phase advance of the light-dark cycle (LD) scheduled food in phase with the new night onset can speed up re-entrainment. In this study, we explored the possible mechanisms underlying the fast re-entrainment due to the feeding schedule. We focused on first- and second-order structures that provide metabolic information to the suprachiasmatic nucleus (SCN). We compared (i) control rats without change in LD cycle; (ii) rats exposed to a 6-h phase advance of the LD cycle with food ad libitum; and (iii) rats exposed to the 6-h phase advance combined with food access in phase with the new night. We found an immediate synchronizing effect of food on stomach distention and on c-Fos expression in the nucleus of the solitary tract, arcuate nucleus of the hypothalamus, dorsomedial hypothalamic nucleus and paraventricular nucleus. These observations indicate that in a model of jet lag, scheduled feeding can favour an immediate shift in first- and second-order relays to the SCN and that by keeping feeding schedules coupled to the new night, a fast re-entrainment may be achieved by shifting peripheral and extra-SCN oscillations.


Assuntos
Ritmo Circadiano , Hipotálamo/fisiologia , Síndrome do Jet Lag/fisiopatologia , Refeições/fisiologia , Fotoperíodo , Animais , Comportamento Alimentar , Hipotálamo/fisiopatologia , Masculino , Ratos , Ratos Wistar
17.
Rev Argent Microbiol ; 49(4): 356-365, 2017.
Artigo em Espanhol | MEDLINE | ID: mdl-28774480

RESUMO

Cocoa plant (Theobroma cacao L.) is native from South America and it represents one of the most significant "bio-cultural" resources of Mesoamerica, since it is a region where it was domesticated and had a relevance as ritual drink and as currency in many pre-hispanic cultures until the arrival of the Spaniards who spread its use worldwide, and became it one of the most consumed commodity goods. Through this research, an alternative is proposed to address the problem of cultivars through the introduction of a wide variety of cocoa plants in traditional agroforestry systems, in synergy with the inoculation of nitrogen-fixing and insoluble phosphor solubilizing edaphic bacterial consortia. Four cultivars of improved grafted cocoa plants were introduced in a traditional agroforestry plot and three fertilization treatments were applied: application of biofertilizer, application of chemical fertilizer and control. Measurements of height, stem diameter, number of leaves and branches were recorded at 2 and 12 months after planting and rhizosphere microbial populations were characterized. Growth results showed good potential for all studied cultivars and it was observed that biofertilization foresees significant effects in some of the growth indicators of cocoa plant. Thereby, plant associations in an agroforestry system could be favorable to promote fruit development and resistance to pests and diseases.


Assuntos
Inoculantes Agrícolas , Cacau , Cacau/crescimento & desenvolvimento , Cacau/microbiologia , Meio Ambiente , Agricultura Florestal , México , América do Sul
18.
Med Intensiva ; 41(9): 539-545, 2017 Dec.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-28969922

RESUMO

INTRODUCTION: The standard method for cardiac output measuring is thermodilution although it is an invasive technique. Transesophageal Echocardiography (TEE) offers a dynamic and functional alternative to thermodilution. OBJECTIVE: Analyze concordance between two TEE methods and thermodilution for cardiac output assessment. METHODS: Observational concordance study in cardiovascular surgery patients that required pulmonary artery catheter. TEE cardiac output measurement at both mitral annulus (MA) and left ventricle outflow tract (LVOT) were performed. Results were compared with thermodilution. Correlation was evaluated by Lin's concordance correlation coefficient and Bland-Altman analysis. Statistical analysis was undertaken in STATA 13.0. RESULTS: Twenty-five patients were enrolled. Fifty two percent of patients were male, median age and ejection fraction was 63 years and 35% respectively. Median thermodilution, LVOT and MA -measured cardiac output was 3.25 L/min, 3.46 L/min and 8.4 L/min respectively. Different values between thermodilution and MA measurements were found (Lin concordance=0.071; Confidence Interval 95%=-0.009 to 0.151; Spearman's correlation=0.22) as values between thermodilution and LVOT (Lin concordance=0.232; Confidence Interval 95%=-0.12 a 0.537; Spearman's correlation 0.28). Bland-Altman analysis showed greater difference between MA measurements and thermodilution (DM=-0.408; Bland-Altman Limits=-0.809 to -0.007), than the other echocardiographic findings (DM=0.007; Bland-Altman Limits=-0.441 to 0.428). CONCLUSION: Results from cardiac output measurement by doppler and 2D-TEE on both MA and LVOT do not correlate with those obtained by thermodilution.


Assuntos
Débito Cardíaco , Procedimentos Cirúrgicos Cardíacos , Cateterismo de Swan-Ganz , Ecocardiografia Transesofagiana , Cuidados Pós-Operatórios/métodos , Termodiluição , Adulto , Idoso , Valva Aórtica , Feminino , Ventrículos do Coração , Humanos , Masculino , Pessoa de Meia-Idade , Valva Mitral , Volume Sistólico , Adulto Jovem
19.
Int J Biometeorol ; 60(8): 1279-86, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26715136

RESUMO

Twenty Dorper × Pelibuey primiparous ewes were used to evaluate effects of seasonal ambient heat stress (i.e., spring vs. summer) on physiological and metabolic responses under production conditions in an arid region. Ten ewes experiencing summer heat stress (i.e., temperature = 34.8 ± 4.6 °C; THI = 81.6 ± 3.2 units) and 10 under spring thermoneutral conditions (temperature = 24.2 ± 5.4 °C; THI = 68.0 ± 4.8 units) were corralled together to measure rectal temperature, respiratory frequency, and skin temperatures at 0600, 1200, 1800, and 2400 h on four occasions over 40 days. Blood metabolite and electrolyte concentrations were also measured at 0600 and 1800 hours. Data were analyzed with a completely randomized design using repeated measurements in time. Rectal and skin temperatures, as well as respiratory frequency, were higher (P < 0.01) in summer than spring at all measured days. Blood serum glucose, cholesterol, triglycerides, and chlorine concentrations were lower (P < 0.01) in summer than spring at 0800 and 1800 hours. In contrast, summer heat stress increased (P < 0.01) blood urea and potassium concentrations at 0800 and 1800 hours. Compared with spring thermoneutral conditions, summer heat stress affected the physiological and metabolic status of hair breed ewes in an arid region, which included blood metabolite and electrolyte adjustments to efficiently cope with summer heat stress.


Assuntos
Transtornos de Estresse por Calor/veterinária , Temperatura Alta/efeitos adversos , Ovinos , Estresse Fisiológico , Animais , Glicemia/análise , Temperatura Corporal , Colesterol/sangue , Clima , Feminino , Transtornos de Estresse por Calor/sangue , Transtornos de Estresse por Calor/fisiopatologia , Umidade , Potássio/sangue , Taxa Respiratória , Estações do Ano , Ovinos/sangue , Ovinos/fisiologia , Triglicerídeos/sangue , Ureia/sangue , Vento
20.
Photochem Photobiol Sci ; 14(3): 543-9, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25355553

RESUMO

In this work a comparative study of the catalytic activity of ZnO-Fe2O3 and ZnO-Fe(0) 0.5 wt% materials was carried out in the degradation of 2,4-dichlorophenoxyacetic acid (2,4-D) as a commercial formulation Hierbamina®, using a compound parabolic collector (CPC) reactor. The catalysts were synthesized by the sol-gel method and characterized by X-ray diffraction, UV-Vis diffuse reflectance spectroscopy, Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy. The textural properties of solids were determined from N2 adsorption isotherms using the Brunauer-Emmett-Teller (BET) method. The incorporation of Fe(0) onto ZnO was demonstrated by X-ray photoelectron spectroscopy analysis. The photocatalytic tests were performed at pH 7, using 10 mg L(-1) of herbicide and 0.5 g L(-1) of catalyst loading. The decay in herbicide concentration was followed by reversed-phase chromatography. A complete degradation of 2,4-D was achieved using ZnO-Fe(0) while 47% of herbicide removal was attained with ZnO-Fe2O3 mixed oxide for an accumulated energy QUV ≈ 2 kJ L(-1). The removal percentage of total organic carbon (TOC) during the solar photocatalytic process was superior using ZnO-Fe(0), achieving 45% compared to the 15% obtained with the mixed oxide catalyst.

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