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The present study was attempted to unveil the impact of heat stress on transcription pattern of major heat shock response genes in caprine cardiac fibroblasts. Cardiac tissues (n = 6) were collected and primary cardiac cell culture was done. Cultured cardiac fibroblasts were kept in an atmosphere of 5% CO2 and 95% air at 38.5 °C. Cardiac cells achieved 70-75% confluence after 72 hours of incubation. Heat stress was induced on confluent cardiac fibroblasts at 42 °C for 0 (control), 20, 60, 100 and 200 min. Quantitative RT-PCR for ß2m (internal control), HSP60, HSP70, HSP90, and HSP110 was done and their transcription pattern was assessed by Pfaffl method. HSP60, HSP90, and HSP110 transcription did not differ at 20 min, up-regulated (p < 0.05) from 60 to 200 min and registered highest at 200 min of heat exposure. HSP70 transcription was gradually escalated (p < 0.05) time dependently from 20 to 200 min and reached zenith at 200 min of heat exposure. Differential induction in transcription of key molecular chaperones at various durations of heat exposure might reduce cardiac fibroblasts apoptosis and thus could maintain cardiac tissue function during heat stress.
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Cabras , Chaperonas Moleculares , Animales , Proteínas HSP70 de Choque Térmico/genética , Proteínas HSP90 de Choque Térmico/genética , FibroblastosRESUMEN
The present study was undertaken to document the transcriptional abundance of heat shock factors and heat shock proteins and their role in survivability of caprine cardiac cells during heat stress. Cardiac tissues were collected from different goats (n = 6) and primary cardiac cell culture was done in an atmosphere of 5% CO2 and 95% air at 38.5 °C. Cardiac cells accomplished 70-75% confluence after 72 h of incubation. Confluent cardiac cells were exposed to heat stress at 42 °C for 0 (control), 20, 60, 100 and 200 min. Quantitative RT-PCR for ß2m (internal control), heat shock factors (HSF1, HSF2, HSF4, HSF5), heat shock proteins (HSP10, HSP40), and Caspase-3 was done and their transcriptional abundance was assessed by Pfaffl method. Transcriptional abundance of HSF1, HSF2, and HSF4 did not change at 20 min, increased (P < 0.05) from 60 to 200 min and reached zenith at 200 min of heat exposure. However, transcriptional abundance of HSF5 was gradually escalated (P < 0.05) from 20 to 200 min and registered highest at 200 min of heat exposure. Transcriptional abundance of HSP10 and HSP40 followed an similar pattern like that of HSF5. Transcriptional abundance of Caspase-3 was significantly down-regulated at 200 min of heat exposure. It could be speculated that over-expression of HSFs and HSPs might have reduced Caspase-3 expression at 200 min of heat exposure suggesting their involvement in cardiac cells survival under heat stress. Moreover, hyper-expression of HSFs and HSPs could maintain the integrity and endurance of cardiac tissues of goats under heat stress.
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Proteínas de Choque Térmico , Factores de Transcripción , Animales , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Caspasa 3/genética , Caspasa 3/metabolismo , Factores de Transcripción del Choque Térmico/genética , Cabras/metabolismo , Respuesta al Choque TérmicoRESUMEN
Ambient temperature is considered as the major abiotic factor which regulates body physiological mechanisms of all living creatures across the globe. Variation in ambient temperature which emulates thermoneutral zone culminates in heat stress. Heat stress has been emerged as major ultimatum to livestock's growth, development, production and reproduction across the world. Livestock's responds to the heat stress via different mechanisms such as behavioral, physiological, biochemical, endocrine and molecular mechanisms. Amongst the aforementioned mechanisms, molecular mechanism plays crucial role to achieve thermo-tolerance via expression of highly conserved family of proteins known as heat shock proteins (HSPs) across livestock species. HSPs serve as molecular chaperones to ameliorate the menace of heat stress in domestic species. In addition, microRNAs are small non-coding RNA which down regulates post-transcriptional gene expression by targeting various HSPs to regulate the thermoregulatory responses in livestock species. Despite of thermal adaptation mechanisms, heat stress breaches animal body homeostasis thereby depresses their production and productivity. Therefore, veterinary researches have been targeting to explore different repertoire of HSPs and microRNAs expression to counteract the rigors of heat stress thereby confer thermo-tolerance in livestock species. The present review highlights the significance of molecular chaperones and microRNAs in the acquisition of thermo-tolerance in dairy cattle.
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MicroARNs , Animales , Bovinos/genética , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Respuesta al Choque Térmico/genética , Calor , MicroARNs/genética , MicroARNs/metabolismo , Chaperonas Moleculares/genética , ReproducciónRESUMEN
We aimed to assess the burden of NCDIs across socioeconomic groups, their economic impact, existing health service readiness and availability, current policy frameworks and national investment, and planned programmatic initiatives in Nepal through a comprehensive literature review. Secondary data from Global Burden of Disease estimates from GBD 2015 and National Living Standard Survey 2011 were used to estimate the burden of NCDI and present the relationship of NCDI burden with socioeconomic status. The Commission used these data to define priority NCDI conditions and recommend potential cost-effective, poverty-averting, and equity-promoting health system interventions. NCDIs disproportionately affect the health and well-being of poorer populations in Nepal and cause significant impoverishment. The Commission found a high diversity of NCDIs in Nepal, with approximately 60% of the morbidity and mortality caused by NCDIs without primary quantified behavioral or metabolic risk factors, and nearly half of all NCDI-related DALYs occurring in Nepalese younger than 40 years. The Commission prioritized an expanded set of twenty-five NCDI conditions and recommended introduction or scale-up of twenty-three evidence-based health sector interventions. Implementation of these interventions would avert an estimated 9680 premature deaths per annum by 2030 and would cost approximately $8.76 per capita. The Commission modelled potential financing mechanisms, including increased excise taxation on tobacco, alcohol, and sugar-sweetened beverages, which would provide significant revenue for NCDI-related expenditures. Overall, the Commission's conclusions are expected to be a valuable contribution to equitable NCDI planning in Nepal and similar resource-constrained settings globally.
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Enfermedades no Transmisibles , Humanos , Nepal , Pobreza , Factores Socioeconómicos , Factores de RiesgoRESUMEN
BACKGROUND: Little is known about the estrogen exposure measurement and mutual effect of age at menarche and age at menopause in the risk of cardiovascular disease (CVD) events. OBJECTIVES: To evaluate estrogen exposure measurement and describe mutual effect of age at menarche and age at menopause in the risk of CVD events. SEARCH STRATEGY: Systematic review of literature in PubMed, Embase and Web of Science for studies published up to 28 June 2020. SELECTION CRITERIA: Observational studies related to estrogen exposure measurement, including mutual effect of age at menarche and age at menopause and risk of CVD events. DATA COLLECTION AND ANALYSIS: Synthesis of evidence was conducted by reviewing individual estimates, followed by meta-analysis. The study received no external funding. MAIN RESULTS: A total of 75 studies were included in synthesis of evidence, of which 17 studies were included in meta-analysis. Reproductive lifespan (age at menopause - age at menarche), endogenous estrogen exposure and total estrogen exposure were used for estrogen exposure measurement. Reproductive lifespan was by far the most commonly used method for estrogen exposure measurement. A shorter reproductive lifespan was associated with a higher risk of CVD events; the pooled relative risk (95% CI) was 1.31 (1.25-1.36) for stroke events. Robust epidemiological studies with measurement of estrogen exposure and associated health risk would strengthen the evidence. CONCLUSIONS: Reproductive lifespan was the most commonly used method for estrogen exposure measurement in epidemiological studies. A shorter reproductive lifespan was associated with a higher risk of CVD events, particularly stroke. TWEETABLE ABSTRACT: A systematic review and meta-analysis found that women with a shorter reproductive lifespan have a higher risk of stroke events.
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Enfermedades Cardiovasculares/etiología , Estrógenos/metabolismo , Menarquia/metabolismo , Menopausia/metabolismo , Factores de Edad , Biomarcadores/metabolismo , Enfermedades Cardiovasculares/metabolismo , Enfermedades Cardiovasculares/mortalidad , Estrógenos/efectos adversos , Femenino , Terapia de Reemplazo de Hormonas/efectos adversos , Humanos , Menarquia/efectos de los fármacos , Menopausia/efectos de los fármacos , Factores de RiesgoRESUMEN
The present study was aimed to determine the impact of thermal stress on expression dynamics of heat shock protein 60 (HSP60) mRNA in cultured cardiac fibroblast cells of the goat. The heart tissues (n = 6) from different goats were used for the culture study. The cardiac fibroblast cells were cultured and subjected to thermal stress at 42 °C for 0, 20, 60 and 100 min. The relative abundance of HSP60 mRNA was assessed by quantitative real-time PCR (qRT-PCR). The cardiac cells exposed to thermal stress at 42 °C for 0 min was taken as control. The relative abundance of HSP60 mRNA did not change at 20 min of thermal stress as compared to control. Thereafter, the relative abundance of HSP60 mRNA was significantly up-regulated (p < 0.05) at 60 min and 100 min of thermal stress. However, the highest mRNA expression of HSP60 was noticed at 100 min of thermal stress. The present study indicates that, thermal stress modulates the mRNA expression HSP60 in cultured caprine cardiac fibroblast cells.
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Chaperonina 60/metabolismo , Fibroblastos/metabolismo , Regulación de la Expresión Génica/fisiología , Cabras , Respuesta al Choque Térmico/fisiología , Miocardio/citología , Animales , Células Cultivadas , Chaperonina 60/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , Factores de Tiempo , Regulación hacia ArribaRESUMEN
High heat and humidity stress have been a perpetual perilous for the buffalo's production and productivity in tropics and subtropics including India. Productive potential of livestock's species including buffaloes is maximum with in thermo-neutral zone (TNZ) and if ambient temperature exceeds TNZ and upper critical temperature expose livestock's to heat stress conditions. For decades, heat stress has been the prime factor to plummet buffalo's growth, development, reproduction and production in tropics and subtropics including India. In general, buffaloes are homeotherms and known as temperature regulators as they resist the variations in ambient temperatures. Generally, buffaloes like other livestock's display amalgamation of thermoregulatory responses to withstand the changes occurred in their micro and macro environment. These thermoregulatory responses are behavioural, physiological, neuro-endocrine and molecular responses acting synergistically to counteract the deleterious effects of heat stress. Amidst all responses, molecular responses play major role to confer thermo-tolerance through expression of highly conserved family of proteins known as heat shock proteins (HSPs). Despite of these thermoregulatory responses, heat stress prodigiously muddles buffalo's production and productivity. The present review highlights the thermoregulatory responses manifested by riverine buffaloes against heat stress.
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Regulación de la Temperatura Corporal , Búfalos/fisiología , Trastornos de Estrés por Calor/fisiopatología , Respuesta al Choque Térmico/fisiología , Animales , Trastornos de Estrés por Calor/veterinariaRESUMEN
The negative impact of heat stress on cattle growth, development, reproduction and production has been quite alarming across the world. Climate change elevates earth surface temperature which exacerbates the wrath of heat stress on cattle. Moreover, cattle in tropical and sub-tropical countries are most commonly affected by the menace of heat stress which severely wane their production and productivity. In general, cattle exhibit various thermoregulatory responses such as behavioural, physiological, neuro-endocrine and molecular responses to counteract the terrible effects of heat stress. Amongst the aforementioned thermoregulatory responses, behavioural, physiological and neuro-endocrine responses are regarded as most conventional and expeditious responses shown by cattle against heat stress. Furthermore, molecular responses serve as the major adaptive response to attenuate the harmful effects of heat stress. Therefore, present review highlights the significance of behavioural, physiological, neuro-endocrine and molecular responses which act synergistically to combat the deleterious effects of heat stress thereby confer thermo-tolerance in cattle.
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Enfermedades de los Bovinos , Trastornos de Estrés por Calor , Animales , Regulación de la Temperatura Corporal , Bovinos , Trastornos de Estrés por Calor/veterinaria , Respuesta al Choque Térmico , Calor , Reproducción , Estrés Fisiológico , TemperaturaRESUMEN
The present study was aimed to document the effect of heat stress on the transcriptional abundance of heat shock protein 70 (HSP70) mRNA in cultured cardiac cells of goat. The heart tissues (n = 6) from different goats were used for the culture study. The cardiac cells obtained from different heart tissues were cultured in 24 well cell culture plates and incubated in a humidified CO2 (5%) incubator at 37 °C. The cardiac cells were allowed to become 75-80% confluent after 72 h of incubation. Thereafter, the cardiac cells were subjected to heat exposure at 42 °C (heat exposed) for 0, 20, 60 and 100 min. The cardiac cells exposed to heat stress at 42 °C for 0 min was taken as control. The relative abundance of HSP70 mRNA was gradually up-regulated (p < .05) from 20 to 100 min of heat exposure and reached the zenith (p < .05) at 100 min of heat challenge. The present finding highlights that, HSP70 could possibly act as a cytoprotective factor and may promote cardiac cell survival against the detrimental effect of heat stress. Moreover, this study may serve as the harbinger to conduct further research work on expression kinetics of HSP70 in cardiac cells of goat including other livestock species.
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Cabras/genética , Proteínas HSP70 de Choque Térmico , Respuesta al Choque Térmico/genética , Miocardio/metabolismo , Animales , Células Cultivadas , Cabras/metabolismo , Cabras/fisiología , Proteínas HSP70 de Choque Térmico/análisis , Proteínas HSP70 de Choque Térmico/genética , Proteínas HSP70 de Choque Térmico/metabolismo , Miocardio/citologíaRESUMEN
Study evaluates the electrochemical performance of off-stoichiometric NixCo3-xO4 compounds. The off-stoichiometric samples were prepared via hydrothermal technique by systematically varying Co/Ni molar ratio. Physical and electrochemical properties of NixCo3-xO4 were observed to be stoichiometry dependent. The increase in Ni/Co ratio in NixCo3-xO4 leads to the morphological transformation from fibrous bundles to urchin like nanospheres with a concomitant increase in the surface area reaching up to 132 m2/g. The optimal specific capacitance of 225 F/g at a current density of 1 A/g and 524 F/g at 10 mV/s scan rate was observed of x 1.0 sample, with an increased retention capacity â¼120% measured at 2 A/g current density. The hybrid density functional theory (DFT) calculations of the electronic density of states identified Ni1.0Co2O4 with optimal band-gap of 2.38 eV with an expectation of displaying higher electrocapacitive performance. Experimentally, Ni0.92Co2.08O4 displayed superior electrocapacitive performance among all Ni/Co ratio in NixCo3-xO4. The DFT study also predicted Ni preference to the octahedral site, which is in-line with the observed increase in ferromagnetic nature, decreased lattice parameter, and increased structural disorder with increasing Ni/Co ratio. The improved electrochemical performance of NixCo3-xO4 (x > 0) is attributed to the mesoporous hierarchical structure, with a high electroactive surface which can effectively improve structural stability, and reduce the ionic and electron diffusion length. Compared to the pure Co3O4, the reduction of Co content in NixCo3-xO4 is desired due to the high cost and toxicity of Co element.
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The role of growth factors in the modulation of ovarian function is an interesting area of research in reproductive biology. Recently, we have shown the expression and role of IGF, EGF, VEGF and FGF in the follicle and CL. Here, we report the presence of Bone Morphogenetic Proteins (BMPs) and their functional receptors in the corpus luteum (CL) of buffalo. The bubaline CL was classified into four stages according to the morphology and progesterone (P4) concentration. The qPCR, immunoblot and immunohistochemistry studies revealed that BMP2 and BMP Receptors (BMPR1A, BMPR1B and BMPR2) were significantly upregulated during the mid stage whereas BMP4 and BMP7 were upregulated during the early stage of CL (P<0.05). Studies on primary luteal cell culture (LCC) using mid CL showed a significant time and concentration dependent effect of BMP4 and BMP7 (P<0.05). At 100ngml-1, the BMPs maximally stimulated the transcripts of StAR, CYP11A1 and 3ßHSD that paralleled with P4 accretion in the media (P<0.05). Further, the BMP4 as well as BMP7 upregulated the transcripts of PCNA and downregulated CASPASE3 in the LCC at the same concentration (P<0.05). Though the combined effect of BMP4 and 7 was significantly higher (P<0.05) than that of individual one, it was not additive. In conclusion, the expression of BMPs and their receptors were dependent on the stages of CL in the buffalo. Treatment of LCC with BMPs in vitro confirmed the presence of functional receptors that stimulated the P4 production and luteal cell survival. Moreover, the results support the concept that the upregulation of P4 and its biosynthetic pathway enzymes such as CYP11A1, StAR and 3ßHSD in the CL is likely due to the autocrine and /or paracrine effects of BMP4 and BMP7 under physiological milieu.
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Proteínas Morfogenéticas Óseas/genética , Búfalos/genética , Cuerpo Lúteo/metabolismo , Regulación de la Expresión Génica , Animales , Apoptosis , Receptores de Proteínas Morfogenéticas Óseas/metabolismo , Proteínas Morfogenéticas Óseas/metabolismo , Caspasa 3/genética , Caspasa 3/metabolismo , Células Cultivadas , Femenino , Perfilación de la Expresión Génica , Immunoblotting , Inmunohistoquímica , Progesterona/genética , Progesterona/metabolismo , Antígeno Nuclear de Célula en Proliferación/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Factores de TiempoRESUMEN
Six male Tharparkar cattle aged 2-3 years were selected for the study. The animals were acclimatized in the psychrometric chamber at thermoneutral zone (TNZ) for 15 days and then exposed to 42 °C temperature up to 23 days followed by 12 days of recovery period. Physiological responses were estimated, and peripheral blood mononuclear cells (PBMCs) were isolated at TNZ on day 1, day 5, and day 12; after 6 h of heat stress exposure on day 16 to day 20, day 25, day 30, day 32, day 34, day 36, and day 38; and a recovery period on day 45 and day 50. The PBMCs were cultured to study the effect of thermal challenge on HSP70 messenger RNA (mRNA) expression pattern at different temperature-time combinations. The mRNA and protein expression of HSP70 in PBMCs along with serum extracellular HSP70 (eHSP70) was increased (P < 0.05) and showed two peaks on day 17 and day 32 (2nd and 17th days of thermal challenge, respectively). The HSP70 mRNA expression was increased (P < 0.05) in a temperature- and time-dependent manner in heat stress challenge treatment as compared to control in cultured PBMCs. HSP70 expression was found to be higher (P < 0.05) after 10 days of heat exposure (corresponds to chronic heat stress) as compared to the first 5 days of heat stress (corresponds to short-term heat stress) and control period at TNZ. The present findings indicate that HSP70 is possibly involved in heat stress adaptive response in Tharparkar cattle and the biphasic expression pattern may be providing a second window of protection during chronic heat stress.
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Enfermedades de los Bovinos/metabolismo , Bovinos/fisiología , Proteínas HSP70 de Choque Térmico/metabolismo , Trastornos de Estrés por Calor/metabolismo , Trastornos de Estrés por Calor/veterinaria , Animales , Temperatura Corporal , Enfermedades de los Bovinos/sangre , Enfermedades de los Bovinos/genética , Proteínas HSP70 de Choque Térmico/sangre , Proteínas HSP70 de Choque Térmico/genética , Trastornos de Estrés por Calor/sangre , Trastornos de Estrés por Calor/genética , Respuesta al Choque Térmico/genética , Respuesta al Choque Térmico/fisiología , Leucocitos Mononucleares/metabolismo , Masculino , ARN Mensajero/metabolismo , Frecuencia RespiratoriaRESUMEN
Six male Tharparkar cattle of 2-3 years old were selected for the study. After 15 days acclimation at thermo neutral zone (TNZ) in psychrometric chamber, animals were exposed at 42°C for 6h up to 23 days followed by 12 days of recovery period. Blood samples were collected during control period at TNZ (day 1, 5 and 12), after heat stress exposure (day 1-10, Short Term Heat Stress Acclimation - STHSA; day 15-23, Long Term Heat Stress Acclimation - LTHSA) and recovery period (day 7 and 12) and peripheral blood mononuclear cells (PBMCs) were isolated for RNA and protein extraction. Serum cortisol concentration was assessed by RIA. The mRNA and protein expression in PBMCs were determined by qPCR and western blot respectively. Samples at TNZ were taken as control. Serum cortisol concentration was increased (P<0.05) during STHSA and gradually declined during LTHSA. Toll like receptor 2 (TLR 2) expression was up regulated (P<0.05) during STHSA and declined to basal level during LTHSA and recovery phase. However, toll like receptor 4 (TLR 4) expression was up regulated (P<0.05) during STHSA and LTHSA while declined in recovery phase. Interleukin 2 (IL2) and interleukin 6 (IL 6) were up regulated (P<0.05) during STHSA and reduced to basal level during LTHSA. PBMCs culture study was conducted to study transcriptional abundance of TLR2/4 and IL2/6 at different temperature-time combinations. The present findings indicate that TLR 2/4 and IL 2/6 could possibly play a vital role in thermo tolerance in Tharparkar cattle during short term and long term heat stress exposure.
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Aclimatación , Bovinos/fisiología , Regulación de la Expresión Génica , Interleucinas/genética , Estrés Fisiológico , Receptores Toll-Like/genética , Animales , Bovinos/sangre , Bovinos/genética , Células Cultivadas , Calentamiento Global , Calor , Hidrocortisona/sangre , MasculinoRESUMEN
The objective of this study was to document the expression and localization of angiopoietin (ANGPT) family members comprising of angiopoietin (ANGPT1 and ANGPT2), and their receptors (Tie1 and Tie2) in buffalo corpus luteum (CL) obtained from different stages of the oestrous cycle, and the modulatory role of ANGPT1 and ANGPT2 alone or in combinations on progesterone (P4 ) secretion and mRNA expression of phosphotidylinositide-3kinase-protein kinase B (PI3K-AKT), phosphoinositide-dependent kinase (PDK), protein kinase B (AKT), Bcl2 associated death promoter (BAD), caspase 3 and von willebrand factor (vWF) in luteal cells obtained from midluteal phase (MLP) of oestrous cycle in buffalo. Real-time RT-PCR (qPCR), Western blot and immunohistochemistry were applied to investigate mRNA expression, protein expression and localization of examined factors whereas, the P4 secretion was assessed by RIA. The mRNA and protein expression of ANGPT1 and Tie2 was maximum (p < .05) in mid luteal phase (MLP) of oestrous cycle. The ANGPT2 mRNA and protein expression was maximum (p < .05) in early luteal phase, decreased in MLP and again increased in late luteal phase of oestrous cycle. ANGPT family members were localized in luteal cells and endothelial cells with a stage specific immunoreactivity. P4 secretion was highest (p < .05) with 100 ng/ml at 72 hr when luteal cells were treated with either protein alone. The mRNA expression of PDK, AKT and vWF was highest (p < .05) and BAD along with caspase 3 were lowest (p < .05) at 100 ng/ml at 72 hr of incubation period, when cultured luteal cells were treated with either protein alone or in combination. To conclude, our study explores the steroidogenic potential of angiopoietins to promote P4 secretion, luteal cell survival and angiogenesis through an autocrine and paracrine actions in buffalo CL.
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Angiopoyetinas/metabolismo , Búfalos/fisiología , Cuerpo Lúteo/metabolismo , Ciclo Estral/fisiología , Neovascularización Fisiológica/fisiología , Progesterona/metabolismo , Angiopoyetinas/genética , Animales , Western Blotting , Caspasa 3/genética , Caspasa 3/metabolismo , Supervivencia Celular/fisiología , Células Cultivadas , Femenino , Regulación de la Expresión Génica/fisiología , Células Lúteas/fisiología , Fosfatidilinositoles/genética , Fosfatidilinositoles/metabolismo , Progesterona/genética , Transporte de Proteínas , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Receptores TIE/genética , Receptores TIE/metabolismo , Proteína Letal Asociada a bcl/genética , Proteína Letal Asociada a bcl/metabolismo , Factor de von Willebrand/genética , Factor de von Willebrand/metabolismoRESUMEN
Pure phase exchange-coupled nanocomposites of hard-soft magnetic oxides, (hard) SrFe10Al2O19(-) (soft) Ni0.75Zn0.25Fe2O4 were prepared via autocombution method. Magnetic properties of the nanocomposites were assessed as a function of soft-phase content in the nanocomposite. A 40% increase in M(s) value was observed for nanocomposite with 30 Wt.% of the soft phase. A linear increase in M(r)/M(s) with soft-phase content indicates the presence of enhanced exchange-coupling between hard and soft phases of the nanocomposite. The highest M(r)/M(s) ratio of 0.68 was obtained for nanocomposite containing 30 Wt.% of the soft-phase. The observed reduction in coercieve field values of the nanocomposite with increase in soft-phase content is explained on the basis of competition between exchange and dipolar interaction between hard-soft and soft-soft phases of the nanocomposite.
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The present paper deals with a steady two-dimensional laminar flow of a viscous incompressible electrically conducting fluid over a shrinking sheet in the presence of uniform transverse magnetic field with viscous dissipation. Using suitable similarity transformations the governing partial differential equations are transformed into ordinary differential equations and then solved numerically by fourth-order Runge-Kutta method with shooting technique. Results for velocity and temperature profiles for different values of the governing parameters have been discussed in detail with graphical representation. The numerical evaluation of skin friction and Nusselt number are also given in this paper.
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Modelos Teóricos , AlgoritmosRESUMEN
The p-n junction photocatalyst, p-CuO/n-ZnO, was prepared via ball milling of ZnO and CuO nanoparticles in water. The structural, optical, and surface properties of the p-n junction photocatalyst p-CuO/n-ZnO were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), UV-Vis spectroscopy, and Zeta potential analyzer. The Photocatalytic activity of the photocatalyst was evaluated via photocatalytic oxidation of Methylene Blue (MB) in the presence of UV light. This study demonstrates a novel p-n junction oxide photocatalyst p-CuO (wt. 10%)/n-ZnO having superior photocatalytic activity (PCA) for the degradation of model dye under the illumination of UV-Vis light. The MB solution was only PCA, degraded by 100% within 15 min by the use of CuO (wt. 10%)/ZnO photocatalyst. Effectivley 365% increase in degradation rate constant was noticed for CuO (10 Wt.%)/ZnO nanocomposite as compared to that of pure ZnO nanoparticles. The enhanced PCA is anticipated from the presence of many micro p-n junctions formed between ZnO-CuO nanoparticles upon ball milling, which helps in efficient electron/hole pair charge separation upon excitation. The study highlights the fact that PCA of p-n junction CuO/ZnO photocatalyst can be effectively tuned by manipulating the interface of the heterostructure and by adjusting the parameters affecting the PCA. The result obtained from PCA is further verified by the zeta potential study.
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The purpose of this study is to enhance the dissolution rate of prednisone by co-grinding with Neusilin to form a complex that can be incorporated into a mini-tablet formulation for pediatrics. Prednisone-Neusilin complex was co-grinded at various ratios (1:1, 1:3, 1:5, and 1:7). The physicochemical properties of the complex were characterized by various analytical techniques including: differential scanning calorimetry (DSC), X-ray powder diffraction (XRPD), scanning electron microscope (SEM), particle size, surface area, solubility, and dissolution rate. The co-grinded prednisone-Neusilin complex (1:7) was blended with other excipients and was formulated into a 2-mm diameter mini-tablet. The mini-tablets were further evaluated for thickness, weight, content uniformity, and dissolution rate. To improve taste masking and stability, mini-tablets were coated by dip coating with Eudragit® EPO solution. DSC and XRPD results showed that prednisone was transformed from crystalline state into amorphous state after co-grinding with Neusilin. Particle size, surface area, and SEM results confirmed that prednisone was adsorbed to Neusilin's surface. Co-grinded prednisone-Neusilin complex (1:7) had a solubility of 0.24 mg/mL and 90% dissolved within 20 min as compared to crystalline prednisone which had a solubility of 0.117 mg/mL and 30% dissolved within 20 min. The mini-tablets containing co-grinded prednisone-Neusilin complex (1:7) exhibited acceptable physicochemical and mechanical properties including dissolution rate enhancement. These mini-tablets were successfully dip coated in Eudragit® EPO solution to mask the taste of the drug during swallowing. This work illustrates the potential use of co-grinded prednisone-Neusilin to enhance solubility and dissolution rate as well as incorporation into a mini-tablet formulation for pediatric use.
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Compuestos de Aluminio/química , Compuestos de Magnesio/química , Pediatría , Prednisona/química , Silicatos/química , Comprimidos , Compuestos de Aluminio/administración & dosificación , Rastreo Diferencial de Calorimetría , Niño , Humanos , Compuestos de Magnesio/administración & dosificación , Microscopía Electrónica de Rastreo , Difracción de Polvo , Prednisona/administración & dosificación , Silicatos/administración & dosificación , SolubilidadRESUMEN
The variable fractional dimensions differential and integral operator overrides the phenomenon of the constant fractional order. This leads to exploring some new ideas in the proposed direction due to its varied applications in the recent era of science and engineering. The present papers deal with the replacement of the constant fractional order by variable fractional order in various fractal-fractional differential equations. An advanced numerical scheme is developed with the help of Lagrange three-point interpolation and further, it is employed for the solution of the proposed differential equations. However, the properties of these new operators are presented in detail. Finally, the error analysis is also conducted for the numerical scheme deployed. The results are validated by the suitable choice of applications to real-life problems. The well- known multi-step-Adams-Bashforth numerical scheme for classical differential equations is recovered when the non-integer order is one.
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OBJECTIVE: The objective of the study was to assess the efficacy and safety profiles of combined treatment of prednisolone with thalidomide (Gr-A) and prednisolone with clofazimine (Gr. B) in patients with erythema nodosum leprosum (ENL) or type 2 lepra reactions. MATERIALS AND METHODS: Efficacy of both regimens was assessed on the basis of clinical recovery of recurrent ENL measured by reaction severity score (RSS), Visual Analog Scale (VAS), and recurrence of type 2 lepra reaction. The causality assessment of adverse drug reactions was done using the WHO UMC causality assessment scale. RESULTS: The average age of patients with recurrent ENL was 42.8 years (male) and 51.8yrs (female) and had mean duration of leprosy and recurrent ENL 2.4 years and 2.09 years, respectively. 80% of nonrecurrence was observed in Gr-A versus 66% in Gr-B. Significant (P < 0.05) lower RSS and VAS was found in both the treatment groups as compared to pretreatment value. The reduction in RSS and VAS was statistically significant (P < 0.05) in Gr-A compared to Gr-B treatment. CONCLUSION: Thalidomide combination with steroid was found to be more efficacious than clofazimine combination with steroid in the treatment of ENL both the treatment regimens showed few tolerable side effects. Improved strategies for the treatment and management of these reactions need to be developed.