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1.
Phys Rev E ; 109(2-1): 024213, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38491670

RESUMEN

Nonequilibrium (NEQ) phonon fluctuation in a nanosystem has been studied through the statistical assessment of the entropy-production and -consumption events in ultrasmall tin dioxide (SnO_{2}) nanorods. Size- and shape-dependent alteration in free energy leading to modulation of the probability distribution function of the phonon dynamics has been observed from the x-ray diffraction and Raman scattering characterizations. The Gallavotti-Cohen nonequilibrium fluctuation theorem has been utilized to qualitatively describe the aforementioned behaviors under the influence of a global flux. The observation of entropy consumption and thermodynamically favorable entropy-production events indicates the presence of NEQ fluctuations in the phonon modes. The effective energy scale of fluctuation in driven phonon modes, dissipating energy faster than relaxation time, is quantified on the order of nanojoules. From optical absorption and photoluminescence studies, the observation of the electron-phonon coupled state confirms the interaction of the NEQ phonons with electrons. The strength of the coupling has been estimated from the temperature-independent Barry center shift and found to be enhanced to 5.35. Valence band x-ray photoelectron spectroscopy and Fourier transformed infrared spectroscopy analyses reconcile NEQ phonon mediated alteration of the valence band density of states, activation of silent phonon modes, and superior excitonic transitions, suitable for the new generation of ultrafast quantum device applications.

2.
Cryo Letters ; 45(1): 36-40, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38538370

RESUMEN

BACKGROUND: Extensive dilution of cattle semen with tris-based extender compromises certain sperm kinetic and functional traits following cryopreservation. OBJECTIVE: To study sperm functions of buffalo bulls under high dilution rates. MATERIALS AND METHODS: Twenty-four ejaculates were harvested twice a week from four buffalo bulls, and diluted to sperm concentrations of 80, 60, 40 and 20 million/mL. Diluted samples were filled in straws, equilibrated at refrigeration temperature for 4 h, and frozen in liquid nitrogen. Frozen sperm samples were thawed for evaluation of kinetic and functional attributes. RESULTS: Compared to 20 million/mL (million/mL) sperm sample, the total motility, progressive motility and rapid motility were reduced (P < 0.05) in 5 million/mL sample. The proportion of live sperm were significantly (P < 0.05) higher in 10, 15 and 20 million/mL samples than in 5 million/mL sample. The percentage of moribund sperm, dead sperm, and sperm with lipid per oxidation increased significantly (P < 0.05) in 5 million/mL sample. CONCLUSION: The reduction of sperm concentrations to < 10 million/mL affects post-thaw Buffalo sperm kinetic and functional attributes.. https://doi.org/10.54680/fr24110110712.


Asunto(s)
Preservación de Semen , Semen , Animales , Bovinos , Masculino , Búfalos , Recuento de Espermatozoides , Motilidad Espermática , Preservación de Semen/veterinaria , Criopreservación/veterinaria , Crioprotectores , Espermatozoides , Análisis de Semen/veterinaria
3.
Cryo Letters ; 44(6): 327-332, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38311926

RESUMEN

BACKGROUND: Antioxidant present in sperm cells protects them from oxidative damage. However, sperm are more susceptible to peroxidative damages due to the loss of these enzymes during cryopreservation and their survival and fertility may be compromised. Insulin like growth factor-1 (IGF-1) has an antioxidant effect and could maintain sperm motility. OBJECTIVE: To improve seminal parameters, mitochondrial membrane potential (MMP), oxidative status and DNA integrity of buck semen after freeze-thawing by fortification of goat semen diluent with various concentrations of IGF-1. MATERIALS AND METHODS: Fifty ejaculates were collected and were extended with tris- citric acid- fructose diluent with 10% egg yolk and 6% glycerol with sperm concentrations of 1×108 mL-1. Post-cryopreserved sperm were assessed for motility and a range of other functional parameters. RESULTS: In post-thaw semen sperm motility, live sperm count, acrosome integrity, hypo-osmotic swelling positive spermatozoa, malondialdehyde (MDA), protein carbonyl content (PCC), TUNEL positive sperm differed significantly (P<0.05) with the various concentrations of IGF-1 used. Sperm functional parameters post-thawing were significantly (P<0.05) better in 250 ng/mL IGF-1. IGF-1 protects against lipid peroxidation by lowering MDA and PCC production, thus reducing the harmful effect of reactive oxygen species. The kidding percentage using the artificial insemination technique was significantly higher ( i.e., 40%) in the group supplemented with 250 ng/mL of IGF-1 than in the non-supplemented group (i.e., 30%). CONCLUSION: IGF-1 may be used to improve post-thaw semen quality and fertility as measured by actual kidding rate. Doi.org/10.54680/fr23610110312.


Asunto(s)
Preservación de Semen , Semen , Animales , Masculino , Análisis de Semen , Potencial de la Membrana Mitocondrial , Cabras , Factor I del Crecimiento Similar a la Insulina/farmacología , Fragmentación del ADN , Carbonilación Proteica , Motilidad Espermática , Criopreservación/métodos , Preservación de Semen/veterinaria , Preservación de Semen/métodos , Espermatozoides , Antioxidantes/farmacología
4.
J Therm Biol ; 97: 102904, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33863422

RESUMEN

The present experiment was aimed to study differential expression of miRNAs and related mRNAs during heat stress (HS) in buffalo heifers. Twelve Murrah buffalo heifers aged between 1.5 and 2.0 years, weighting between 250 and 300 Kg were randomly assigned into two equal groups. The animals were kept in the psychrometric chamber under Thermo-neutral (TN; THI = 72) and HS (THI = 87-90) conditions for 6 h every day between 1000 and 1600 h for 21 days. The blood sampling was done at 1500 h on 15th day of the experiment and physiological parameters viz. pulse rate (PR), respiratory rate (RR) and rectal temperature (RT) were recorded at 1500 h on day -5, -3, -1, 0, +1, +3, +5 with respect to blood sampling. PBMCs were used for extraction of miRNAs and total RNA; and first strand cDNA was synthesized. qPCR was performed for relative gene expression studies. Physiological, hematological (erythrocytic indices), biochemical (triglycerides, urea, ALT, AST, LDH), redox (SOD, ROS) and endocrine parameters (T4) altered significantly (P < 0.05) during HS as compared to TN. Out of eight targeted miRNAs only four were expressed in buffalo heifers. The relative expression of bta-mir-142, bta-mir-1248 and bta-mir-2332 was significantly (P < 0.05) up-regulated whereas expression of bta-mir-2478 was significantly (P < 0.05) down-regulated during HS as compared to TN. The relative expression of the predicted target genes i.e. HSF1, HSP60, HSP70, HSPA8 and HSP90 were significantly (P < 0.05) up-regulated whereas HSF4 expression was significantly (P < 0.05) down-regulated during HS as compared to TN. It can be concluded that a THI of 87-90 could lead to a moderate HS in buffalo heifers. Differential expression studies of miRNAs and related mRNAs in present study deciphers the role of miRNAs in the heat tolerance in buffalo heifers.


Asunto(s)
Búfalos/genética , Trastornos de Estrés por Calor/genética , Respuesta al Choque Térmico/genética , Calor/efectos adversos , Humedad/efectos adversos , MicroARNs , ARN Mensajero , Animales , Búfalos/sangre , Femenino , Factores de Transcripción del Choque Térmico/genética , Trastornos de Estrés por Calor/sangre , Trastornos de Estrés por Calor/veterinaria , Proteínas de Choque Térmico/genética , Pruebas Hematológicas , Estrés Oxidativo , Proteínas Ribosómicas/genética
5.
Reprod Domest Anim ; 55(9): 1080-1092, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32531861

RESUMEN

Estrogen and its receptors are essential for sexual development and reproduction. Oestrogen receptor alpha (ERα) is a nuclear receptor activated by the hormone oestrogen. In male, ERα is encoded by the gene ESR1 (oestrogen receptor1) responsible for better fertility. ESR1 is involved in the reabsorption of luminal fluid during the transit of spermatozoa from the testis to the head of the epididymis which is important for their survival and maturation during epididymal storage. The absence of ESR1 leads to reduced epididymal sperm content, reduced sperm motility and fertilizing ability. The present study was undertaken to investigate the expression and presence of ESR1 gene in fertile and low-fertile male goat breeds. We identified ESR1 gene through various molecular tools. Genotyping was carried out by high resonance melting analysis using Roche Light Cycler 480(LC-480) system and found three different genotypes. Genotypic frequency-AA (blue-0.67), BB(Red-0.2), AB(Green-0.08) with allele frequency A(0.71 and B (0.29). The predominance of this gene in head of epididymis in fertile bucks was confirmed by SDS-PAGE, Western blotting and immunohistochemistry. From the results, we corroborated that the present study provides a useful and effective way to predict male fertility in goat breeds, which in turn increases the percentage of fertility in flock leading to more number of offspring in a kidding season.


Asunto(s)
Receptor alfa de Estrógeno/genética , Fertilidad/genética , Cabras/genética , Animales , Cruzamiento , Receptor alfa de Estrógeno/metabolismo , Regulación de la Expresión Génica , Genitales Masculinos/metabolismo , Genotipo , Cabras/fisiología , Masculino , Análisis de Semen/veterinaria
6.
Anim Reprod Sci ; 210: 106190, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31635784

RESUMEN

This study was conducted to characterise pregnancy-associated glycoprotein (caPAG) in peripheral plasma during gestation and postpartum periods of nulliparous and multiparous does with one or two foetuses using a caPAG specific two-step sandwich ELISA system. Earliest time-points for detection of pregnancy and foetal number with appropriate cut-off values were identified. Plasma samples from 15 pregnant (multiparous: n = 8; nulliparous: n = 7; during pregnancy and postpartum period) and six non-pregnant (during oestrous cycle) goats were collected and analysed. Mean caPAG concentration was greater than the threshold for pregnancy detection (S-N = 0.40) on d22, peaked on d45 and remained unchanged until parturition. From d45 until parturition, caPAG concentration in multiparous does with two foetuses was 1.4 to 1.8 fold greater (P < 0.001) than those with one foetus. For the ELISA, 0.83 (S-N) was the most appropriate cut-off to differentiate does with two from those with a single foetus with an overall sensitivity and accuracy of 88.9% and 84.7%, respectively. Circulating caPAG concentration in multiparous goats was greater (P < 0.05) compared with nulliparous goats during the early pregnancy and postpartum periods. After parturition, caPAG concentrations markedly decreased and were basal within 14 days postpartum. In conclusion, using the caPAG specific ELISA, results indicated there were unique gestational and postpartum profiles for caPAG concentrations that are affected by number of foetuses and parity of the doe. The marked decrease in concentration of caPAG following parturition indicates there would not be compromising of the detection of subsequent pregnancies in goats using this technique.


Asunto(s)
Cabras/fisiología , Tamaño de la Camada , Periodo Posparto/sangre , Proteínas Gestacionales/sangre , Preñez , Animales , Femenino , Regulación de la Expresión Génica/fisiología , Cabras/sangre , Paridad , Embarazo , Proteínas Gestacionales/genética , Proteínas Gestacionales/metabolismo , Preñez/fisiología
7.
Cryo Letters ; 39(6): 386-390, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30963156

RESUMEN

BACKGROUND: The membrane and acrosomal integrity of sperm play a vital role in fertilization process; however they are compromised upon cryopreservation. OBJECTIVE: To study the effect of cholesterol-loaded cyclodextrin (CLC) on membrane and acrosome status of Hariana bull sperm during cryopreservation. MATERIALS AND METHODS: Semen samples collected from Hariana bulls with mass motility ≥ 3+ and individual progressive motility ≥ 70% were utilized in the study. Each ejaculate was split into two parts, one part being evaluated freshly for various seminal attributes and the other part being diluted in Tris diluent (without egg yolk and glycerol) to obtain a final concentration of 120×106 sperm/mL. The diluted semen was divided into four treatments: Group I, without CLC (control); Group II, with CLC at 0.5 mg per 120 million sperm; Group III, at 1.0 mg per 120 million sperm; Group IV, at 2.0 mg per 120 million sperm. All aliquots were incubated for 15 min at 37°C and each sample was diluted with Egg yolk-Tris-Glycerol (EYTG) extender up to 80×106 sperm/mL. The diluted semen samples were packed in French mini straws (0.25 mL), sealed and equilibrated at 4°C for 4 h followed by cryopreservation. The samples at pre-freeze and post-thaw stage were evaluated for membrane and acrosomal integrity, as well as primary, secondary and tertiary acrosomal damages. RESULTS: The membrane and acrosomal integrity was significantly higher in group II as compared to groups I, III, and IV, at pre-freeze and post-thaw stage (P<0.05). The primary and secondary acrosomal damage were significantly reduced in group II compared to other groups (P<0.05). No significant difference in tertiary acrosomal damage was found among different groups. CONCLUSION: CLC improves the membrane and acrosomal integrity, and reduces primary and secondary acrosomal damages during cryopreservation of Hariana bull sperm.


Asunto(s)
Acrosoma/fisiología , Bovinos , Colesterol/química , Criopreservación/veterinaria , Crioprotectores/química , Ciclodextrinas/química , Preservación de Semen/veterinaria , Animales , Membrana Celular/fisiología , Masculino , Motilidad Espermática , Espermatozoides
8.
Nanotechnology ; 28(44): 445704, 2017 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-28820424

RESUMEN

Bovine serum albumin (BSA)-protected gold clusters (atomicity âˆ¼ 20), prepared using a wet chemical route, show strong dipolar radiative transition with a gap energy of 1.93 eV due to the high oscillator strength, as confirmed by the emission studies. Self-arrangement of the clusters with fixed atomicity yields a low dispersive dielectric and electric self-polarization nature. The electrical hysteresis loop measurements returned a remanent polarization of 0.05 µC cm-2, which can be correlated with the dipolar orientation (activation energy âˆ¼ 45.32 meV), originating from the structure-dependent deformation of the charge density.

9.
Public Health ; 147: 92-97, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28404504

RESUMEN

OBJECTIVE: Chhattisgarh in India is a malaria-endemic state with seven southern districts that contributes approximately 50-60% of the reported malaria cases in the state every year. The problem is further complicated due to asymptomatic malaria cases which are largely responsible for persistent transmission. This study was undertaken in one of the forested villages of the Keshkal subdistrict in Kondagaon district to ascertain the proportion of the population harbouring subclinical malarial infections. STUDY DESIGN: Community-based cross-sectional study. METHODS: Mass blood surveys were undertaken of the entire population of the village in the post-monsoon seasons of 2013 and 2014. Fingerprick blood smears were prepared from individuals of all ages to detect malaria infections in their blood. Individuals with fever at the time of the survey were tested with rapid diagnostic tests, and parasitaemia in thick blood smears was confirmed by microscopy. Malaria-positive cases were treated with anti-malarials in accordance with the national drug policy. RESULTS: Peripheral blood smears of 134 and 159 individuals, including children, were screened for malaria infection in 2013 and 2014, respectively. Overall, the malaria slide positivity rates were 27.6% and 27.7% in 2013 and 2014, respectively, and the prevalence rates of asymptomatic malaria were 20% and 22.8%. This study showed that, for two consecutive years, the prevalence of asymptomatic malaria infection was significantly higher among children aged ≤14 years (34.4% and 34.1% for 2013 and 2014, respectively) compared with adults (15.2% and 18.2% for 2013 and 2014, respectively; P = 0.023 and 0.04, respectively). CONCLUSION: The number of asymptomatic malaria cases, especially Plasmodium falciparum, is significant, reinforcing the underlying challenge facing the malaria elimination programme in India.


Asunto(s)
Enfermedades Asintomáticas , Costo de Enfermedad , Malaria/epidemiología , Adolescente , Adulto , Anciano , Niño , Preescolar , Estudios Transversales , Femenino , Humanos , India/epidemiología , Lactante , Malaria/prevención & control , Masculino , Persona de Mediana Edad , Prevalencia , Adulto Joven
10.
Iran J Vet Res ; 17(4): 226-230, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-28224004

RESUMEN

To study the influence of season on oxidative status of buffalo semen and their association with semen characteristics and seminal plasma proteins, ejaculates were collected twice a week in winter, summer and rainy seasons from six adult Bhadawari buffalo bulls. The neat semen was analyzed for semen characteristics immediately after collection and oxidative status viz. lipid peroxidation (LPO), catalase (CAT), super oxide dismutase (SOD) activity, and total protein (TP) were estimated in seminal plasma. The protein profiling was carried out by one-dimensional sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE). The significant effect of season was observed on TP, SOD activity and % protein fractions of seminal plasma proteins of buffalo bulls. The TP values showed positive correlation with ejaculate volume (EV), sperm concentration (SC), and % live-dead (LD) and negative correlation with progressive motility (PM), and hypo-osmotic swelling test (HOST). The SOD activity showed positive correlation with PM, LD, HOST and % acrosoamal integrity (AI). Besides that, results showed correlation of TP with 6.5, 38 and 66 kDa proteins, LPO with 70, 72, 84 and 86 kDa proteins, CAT with 70 kDa and 86 kDa proteins, and SOD with 6.5, 24.5, 44.5, 70 and 72 kDa proteins. In conclusion, this study indicated that TP and SOD activity of seminal plasma of buffalo bulls were influenced by season and were found to be associated with some of the semen characteristics and expression of seminal plasma proteins.

11.
Reprod Domest Anim ; 49(3): 387-91, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24597848

RESUMEN

The study was designed to evaluate the influence of season on semen characteristics and seminal plasma protein profile of buffalo bull semen. Thirty-six ejaculates were collected in three seasons (winter, summer and rainy) from six adult Bhadawari bulls, and semen characteristics were evaluated immediately after collection. The seminal plasma was harvested by centrifugation and protein profiling, and percentage protein fractions were analysed by SDS-PAGE. The significant effect of season was observed on ejaculate volume, sperm concentration, progressive motility, percentage live spermatozoa, hypo-osmotic swelling test (HOST) and acrosomal integrity. The electrophoretogram of seminal plasma proteins revealed 20 protein bands in winter, 23 bands in rainy and 25 bands in summer seasons, illustrating the significant effect of seasons on seminal plasma proteins. Among these protein bands, 18 bands were observed common in semen samples of all three seasons while protein bands of 46, 55, 58, 144 and 160 kDa were found in rainy and summer seasons. The protein bands of 48 and 60 kDa were observed only in winter season, whereas 184 and 200 kDa were reported in summer season only. The protein fractions (protein%) of common protein bands observed in three seasons revealed a significant effect of season on protein bands of 24.5, 66, 70, 72, 84 and 86 kDa. From the study, it was pertinent that bull seminal plasma contains specific proteins in particular season, which may be associated with some of the semen characteristics, and these proteins could be used as markers of the semen quality of buffalo bulls.


Asunto(s)
Búfalos/metabolismo , Estaciones del Año , Análisis de Semen/veterinaria , Semen/química , Proteínas de Plasma Seminal/análisis , Acrosoma/ultraestructura , Animales , Electroforesis en Gel de Poliacrilamida/veterinaria , India , Masculino , Análisis de Semen/métodos , Recuento de Espermatozoides , Motilidad Espermática
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