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1.
Nature ; 614(7946): 48-53, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36725994

RESUMO

Scattering of high energy particles from nucleons probes their structure, as was done in the experiments that established the non-zero size of the proton using electron beams1. The use of charged leptons as scattering probes enables measuring the distribution of electric charges, which is encoded in the vector form factors of the nucleon2. Scattering weakly interacting neutrinos gives the opportunity to measure both vector and axial vector form factors of the nucleon, providing an additional, complementary probe of their structure. The nucleon transition axial form factor, FA, can be measured from neutrino scattering from free nucleons, νµn → µ-p and [Formula: see text], as a function of the negative four-momentum transfer squared (Q2). Up to now, FA(Q2) has been extracted from the bound nucleons in neutrino-deuterium scattering3-9, which requires uncertain nuclear corrections10. Here we report the first high-statistics measurement, to our knowledge, of the [Formula: see text] cross-section from the hydrogen atom, using the plastic scintillator target of the MINERvA11 experiment, extracting FA from free proton targets and measuring the nucleon axial charge radius, rA, to be 0.73 ± 0.17 fm. The antineutrino-hydrogen scattering presented here can access the axial form factor without the need for nuclear theory corrections, and enables direct comparisons with the increasingly precise lattice quantum chromodynamics computations12-15. Finally, the tools developed for this analysis and the result presented are substantial advancements in our capabilities to understand the nucleon structure in the weak sector, and also help the current and future neutrino oscillation experiments16-20 to better constrain neutrino interaction models.

2.
Phys Rev Lett ; 131(1): 011801, 2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37478458

RESUMO

Neutrino-induced charged-current single π^{+} production in the Δ(1232) resonance region is of considerable interest to accelerator-based neutrino oscillation experiments. In this Letter, high statistic differential cross sections are reported for the semiexclusive reaction ν_{µ}A→µ^{-}π^{+}+ nucleon(s) on scintillator, carbon, water, iron, and lead targets recorded by MINERvA using a wideband ν_{µ} beam with ⟨E_{ν}⟩≈6 GeV. Suppression of the cross section at low Q^{2} and enhancement of low T_{π} are observed in both light and heavy nuclear targets compared with phenomenological models used in current neutrino interaction generators. The cross sections per nucleon for iron and lead compared with CH across the kinematic variables probed are 0.8 and 0.5 respectively, a scaling which is also not predicted by current generators.

3.
Phys Rev Lett ; 131(5): 051801, 2023 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-37595210

RESUMO

MINERvA has measured the ν_{µ}-induced coherent π^{+} cross section simultaneously in hydrocarbon (CH), graphite (C), iron (Fe), and lead (Pb) targets using neutrinos from 2 to 20 GeV. The measurements exceed the predictions of the Rein-Sehgal and Berger-Sehgal PCAC based models at multi-GeV ν_{µ} energies and at produced π^{+} energies and angles, E_{π}>1 GeV and θ_{π}<10°. Measurements of the cross-section ratios of Fe and Pb relative to CH reveal the effective A scaling to increase from an approximate A^{1/3} scaling at few GeV to an A^{2/3} scaling for E_{ν}>10 GeV.

4.
Phys Rev Lett ; 130(16): 161801, 2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-37154647

RESUMO

This Letter presents the first simultaneous measurement of the quasielasticlike neutrino-nucleus cross sections on C, water, Fe, Pb, and scintillator (hydrocarbon or CH) as a function of longitudinal and transverse muon momentum. The ratio of cross sections per nucleon between Pb and CH is always above unity and has a characteristic shape as a function of transverse muon momentum that evolves slowly as a function of longitudinal muon momentum. The ratio is constant versus longitudinal momentum within uncertainties above a longitudinal momentum of 4.5 GeV/c. The cross section ratios to CH for C, water, and Fe remain roughly constant with increasing longitudinal momentum, and the ratios between water or C to CH do not have any significant deviation from unity. Both the overall cross section level and the shape for Pb and Fe as a function of transverse muon momentum are not reproduced by current neutrino event generators. These measurements provide a direct test of nuclear effects in quasielasticlike interactions, which are major contributors to long-baseline neutrino oscillation data samples.

5.
Phys Rev Lett ; 129(2): 021803, 2022 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-35867435

RESUMO

Neutrino charged-current quasielastic-like scattering, a reaction category extensively used in neutrino oscillation measurements, probes nuclear effects that govern neutrino-nucleus interactions. This Letter reports the first measurement of the triple-differential cross section for ν_{µ} quasielastic-like reactions using the hydrocarbon medium of the MINERvA detector exposed to a wideband beam spanning 2≤E_{ν}≤20 GeV. The measurement maps the correlations among transverse and longitudinal muon momenta and summed proton kinetic energies, and compares them to predictions from a state-of-art simulation. Discrepancies are observed that likely reflect shortfalls with modeling of pion and nucleon intranuclear scattering and/or spectator nucleon ejection from struck nuclei. The separate determination of leptonic and hadronic variables can inform experimental approaches to neutrino-energy estimation.

6.
Anim Biotechnol ; 32(4): 526-530, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31961249

RESUMO

The depth of intravaginal insemination to achieve optimum fertility with frozen-thawed semen is highly species specific in birds and differ even in breed and/or strains of a species. Therefore, study was designed to evaluate the influence of intravaginal insemination depths (2 and 4 cm) on fertility outcome in Indian red jungle fowl. Semen collected from eight mature cocks was pooled, diluted in extender and cooled to 4 °C. Glycerol (20%) was added to chilled semen, equilibrated for 10 min and cryopreserved. After 3 days of storage, frozen semen was thawed in water bath at 37 °C for 30 s. After glycerol removal, intravaginal Inseminations were performed at the depth of 2 and 4 cm. The no. of fertilized eggs (31.4 ± 1.6 vs. 27.7 ± 1.8), fertility rate (65.7 ± 3.6 vs. 58.8 ± 4.0), no. of hatched chicks (27.8 ± 1.9 vs. 23.5 ± 1.6), hatchability of set eggs (58.8 ± 4.3 vs. 49.7 ± 3.2) and hatchability of fertilized eggs (88.4 ± 2.8 vs. 84.3 ± 2.2) were recorded higher with intravaginal depth of 4 cm compared to 2 cm. It is concluded that intravaginal insemination at the depth of 4 cm enhances the fertility outcomes of the frozen-thawed Indian red jungle fowl semen.


Assuntos
Galinhas , Fertilidade , Inseminação Artificial/veterinária , Animais , Glicerol , Óvulo
7.
Cryo Letters ; 42(6): 332-340, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35366299

RESUMO

BACKGROUND: Egg yolk is inevitably associated with risks of microbial contamination and anti-cryoprotectant agents that necessitate the investigation of some synthetic alternatives. OBJECTIVE: To investigate the potential of carboxylated poly-L-lysine (CPLL) as a replacement for egg yolk during the cryosurvivability of Nili-Ravi buffalo sperm. MATERIALS AND METHODS: Semen collected from four Nili-Ravi buffalo bulls (two ejaculates / bull / day; total 40 ejaculates for five replicates) was cryopreserved in different experimental extenders viz: Control (CPLL 0%, egg yolk 20%); E1 (CPLL 5%, egg yolk 15%); E2 (CPLL 10%, egg yolk 10%); E3 (CPLL 15%, egg yolk 5%) and E4 (CPLL 20%, egg yolk 0%). Post-thaw quality was assessed in terms of sperm motility, plasma membrane integrity (PMI), viability, live:dead ratio, lipid peroxidation of sperm and total antioxidant capacity of seminal plasma. RESULTS: Sperm motility improved (P<0.05) in extenders replacing 5%, 10% and 15% egg yolk with CPLL. Sperm PMI, viability and live:dead ratio also improved (P<0.05) in extenders replacing 10%, 15% and whole (20%) egg yolk with CPLL. In contrast, sperm DNA integrity was not different (P>0.05) when CPLL replaced egg yolk at any level. The lipid peroxidation level decreased with a concomitant increase in total antioxidant activity of seminal plasma when CPLL replaced egg yolk at 5%, 10%, 15% and 20%. CONCLUSION: Replacement of 15% egg yolk in the extender with CPLL improves all sperm quality parameters: motility, PMI, viability, live:dead ratio, lipid peroxidation of sperm and total antioxidant activity of seminal plasma.


Assuntos
Búfalos , Preservação do Sêmen , Animais , Criopreservação/veterinária , Gema de Ovo , Masculino , Polilisina/farmacologia , Preservação do Sêmen/veterinária , Motilidade dos Espermatozoides , Espermatozoides
8.
Child Youth Serv Rev ; 122: 105912, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33390637

RESUMO

BACKGROUND: The most recent global pandemic of COVID-19 has been creating multidimensional damages, including a detrimental impact on the mental health status of individuals. Medical students, a vulnerable cross-section of the population, may have perceived a myriad of psychological stressors during this crisis in the background of their prevailing stressful academic pressure and preexisting higher psychological and mental health issue. OBJECTIVE: To determine the prevalence of anxiety and depressive symptoms and to elucidate the psychological impact of COVID-19 pandemic on Bangladeshi medical students. METHOD: A cross-sectional study design was utilized to conduct this survey. The online survey including demographic questions, COVID-19 related questions, and the Hospital Anxiety and Depression Scale (HADS; higher scores on the subscales indicate higher levels of depressive and anxiety symptoms), was completed by 425 Bangladeshi medical students. Collected data were statistically analyzed by using SPSS (version 25.0) software. RESULT: The HADS anxiety subscale revealed that 65.9% of the medical students had different levels of anxiety, ranging from mild (27.3%), moderate (26.8%), and severe (11.8%). As per HADS depression subscale, 49.9% of the medical students had varying degrees of depressive symptoms, with 3.3% of the participants had suffered from severe depressive symptoms. Female students had a relatively more anxiety and depressive symptoms when compared with males. The students, who were severely tensed of getting infected by the virus, were at higher risk of suffering from anxiety (3.5-fold) and depressive (2.7-fold) symptoms, when compared with no/minimally stressed students. Besides, fear of getting assaulted or humiliated on the way to hospital or home, not to be able to give maximum concentration on study after COVID-19 pandemic, students' present emotional status (agitation), had statistically significant higher risk of anxiety. CONCLUSION: A substantial proportion of Bangladeshi medical students are experiencing pandemic-related adverse psychological impact. Poor mental health conditions of these vulnerable medical students pose important threat to their potential contribution in future health care. Thus, medical colleges and health authorities should focus on addressing their psychological needs and formulate effective strategies to ameliorate medical students' mental health status, particularly during any infectious disease outbreak.

9.
Ecotoxicol Environ Saf ; 202: 110865, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32570103

RESUMO

Crop production in acid soils is facing enormous challenges due to low soil quality associated with an increase in the acidification rate and aluminum toxicity. Despite comprehensive prior work with biochar application on nutrient availability and crop productivity in acid soils, little information is available about the recommendation or standardization of biochar application rates that are more suitable for soil fertility improvement under different soil environments (physico-chemical properties) for maximizing the benefits of biochar applications and minimizing the potential environmental risk. Thus, the objective of this study was to investigate the effectiveness of poultry litter (PL) and poultry litter biochar (PLB) in ameliorating the fertility of acid soils through incubation and pot experiments. The soil was amended with different materials as follows; lime (1 g kg-1), PL (5, 10 and 15 g kg-1) and PLB (5, 10 and 15 g kg-1) along with control (non-amended). A pot experiment was also conducted using similar treatments to observe the responses of maize crop to the different amendments. The results indicated an increase in the pH and a decrease in exchangeable acidity in lime, PL and PLB amended soils. Lower soil pH, base cations and soil available phosphorus (P), and higher exchangeable acidity were found in control than the amended soils. Compared to PL and lime, PLB achieved greater increase rate in soil pH and reduction rate in soil exchangeable acidity with increased soil exchangeable base cations. An increase in soil available calcium (Ca) was observed in the lime treatment, while in PL and PLB treatments, there was an increase in soil available Ca, magnesium (Mg), potassium (K) and P. Application of the amendments increased availability of nitrogen (N), P, K, Ca and Mg relative to the control for maize in the pot experiment. When PL and PLB amendments were compared, it was found that the PLB was the best choice for the amelioration of acid soils as well as nutrient uptake by maize plants. It is suggested that application of PLB at the rate of 15 g kg-1 is suitable for maize growth in acid soils.


Assuntos
Carvão Vegetal , Recuperação e Remediação Ambiental/métodos , Zea mays/fisiologia , Ácidos , Animais , Cálcio , Compostos de Cálcio , Magnésio , Nitrogênio , Óxidos , Fósforo , Potássio , Aves Domésticas , Solo/química , Poluentes do Solo/análise , Zea mays/crescimento & desenvolvimento
10.
Cryo Letters ; 40(6): 347-351, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-33966061

RESUMO

BACKGROUND: The quality of cryopreserved buffalo semen is low due to high susceptibility of sperm membranes to cold shock. OBJECTIVE: The present study was designed to investigate the effect of recombinant type-III antifreeze protein from the eel pout Macrozoarces americanus (rAFPIII) on freezability of buffalo semen. MATERIALS AND METHODS: Semen was collected from three buffalo bulls for three weeks (replicates). Qualified ejaculates (N=18) were split into four aliquots and diluted in Tris-citric acid extender containing 0.0, 0.1, 1 and 10 µg mL-1 of rAFPIII. Semen was cooled to 4 C, evaluated for sperm motility and PMI, cryopreserved and assessed for post-thaw quality. RESULTS: Supplementation of the extender with rAFPIII didn't affect motility and PMI of chilled semen. Post-thaw sperm motility and PMI were higher in extender supplemented with rAFPIII (10µg mL-1) compared to control. Sperm viability and acrosome integrity remained the same. CONCLUSION: Addition of rAFPIII in extender improved motility and PMI of cryopreserved buffalo semen.

11.
BJOG ; 125(5): 616-622, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28467691

RESUMO

OBJECTIVE: To determine the quality of life (QOL) of fistula patients in Bangladesh who have undergone ileal conduit (IC) urinary diversion operations, and to assess whether the risks and ethical challenges involved, outweigh the reality of leaving a woman with urinary incontinence for the rest of her life. DESIGN: Observational study. SETTING: LAMB Hospital, Bangladesh. POPULATION: Seventeen women who had undergone IC between February 2012 and March 2016: 14 women previously had irreparable obstetric fistulas and three had bladder exstrophy. METHODS: Demographic, obstetric, IC-related, stigma and discrimination information were collected by questionnaire. Univariate analysis was done using the two-sided t-test for comparison of differences before and after IC surgery. MAIN OUTCOME METHODS: Change in stigma and discrimination scores. Health-related QOL assessed using the 36-item Short Form Health Survey. RESULTS: Of the 17 women, 14 (82.3%) felt they were cured of their fistula disease. Three complained of occasional leakage due to insufficient seal of the bag, mainly at night, and all but one experienced no limits to their daily activities. Stigma and discrimination scores were significantly lower after having the IC surgery. The mean difference from when the woman had a fistula to when she had an IC for stigma score was 3.17 (1.12-4.16, P < 0.001), and for discrimination score was 3 (1.9-4.1, P < 0.001). CONCLUSION: Overall, there has been improved QOL following IC among the women in this study and all would recommend IC to women in the same situation. They remain chronic patients with some physical symptoms, but are well re-integrated back into their communities. TWEETABLE ABSTRACT: Improved QOL following ileal conduit in women with persistent fistula related disorder in Bangladesh.


Assuntos
Extrofia Vesical , Fístula Vesicovaginal , Bangladesh , Feminino , Humanos , Qualidade de Vida , Derivação Urinária
12.
Andrologia ; 50(6): e13020, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29700838

RESUMO

The free radical scavenging activity (RSA) of Nigella sativa extract and its efficiency for cryopreservation of buffalo spermatozoa was investigated. In experiment 1, Nigella sativa extract was prepared and evaluated for RSA using 2,2-diphenyl-1-picrylhydrazyl assay. The results showed increased pattern of RSA at 1%-5% of Nigella sativa extract. In experiment 2, buffalo semen from three bulls (24 ejaculates) was incubated at 0%, 0.1%, 0.3%, 0.5%, 1%, 1.5%, 2%, 3%, 4%, 5% and 6% extract to assess in vitro tolerability to Nigella sativa in terms of progressive motility (PM). Buffalo spermatozoa showed tolerance to all levels; rather, sperm PM was increased at 1%-4% extract. In experiment 3, semen from three bulls (24 ejaculates) was cryopreserved with 0%, 1%, 2%, 3%, 4% and 5% of Nigella sativa extract. Sperm PM and plasma membrane integrity (PMI) were evaluated after dilution and cooling, while PM, PMI, viability and DNA integrity were evaluated after thawing. Nigella sativa extract at 4% in extender improved (p < .05) post-dilution, post-cooling and post-thaw sperm quality. In conclusion, Nigella sativa extract at all concentrations (1%-6%) showed antioxidant activity and its supplementation at 4% in extender improved buffalo sperm quality at all stages of cryopreservation.


Assuntos
Búfalos , Criopreservação/métodos , Nigella sativa , Extratos Vegetais/farmacologia , Preservação do Sêmen/métodos , Espermatozoides/efeitos dos fármacos , Animais , Crioprotetores/farmacologia , Sequestradores de Radicais Livres/farmacologia , Masculino
13.
Reprod Domest Anim ; 53(2): 377-384, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29239046

RESUMO

Routinely, swim-up method is used to separate high-quality sperm; however, long processing time and close cell-to-cell contact during the centrifugation step are inevitable elements of oxidative stress to sperm. The objective was to evaluate Sephadex™ and glass wool filtration to separate motile, intact and viable sperm for in vitro fertilization in buffalo. The cumulus-oocyte complexes (COCs) were collected from ovaries of slaughtered buffaloes by aspiration and matured for 24 hr in CO2 incubator at 38.5°C and 5% CO2 . Matured COCs were rinsed twice in fertilization TALP and placed in the pre-warmed fertilization medium without sperm. Cryopreserved buffalo semen was thawed at 37°C for 30 s and processed through Sephadex™ , glass wool filtration and swim-up (control). Total and motile sperm recovery rates were assessed, resuspended in fertilization TALP and incubated for 15-20 min in CO2 incubator. Samples prepared by each method were divided into two aliquots: one aliquot was studied for sperm quality (progressive motility, membrane integrity, viability, liveability), while the other was subjected to co-incubation with sets of 10-15 in vitro matured oocytes. Data on sperm quality were analysed by ANOVA, while in vitro fertilizing rates were compared by chi-squared test using SPSS-20. Least significant difference (LSD) test was used to compare treatment means. Glass wool filtration yielded higher total and motile sperm recovery rate, while Sephadex™ filtration improved (p < .05) sperm quality (progressive motility, membrane integrity, viability, liveability). Sperm preparation through Sephadex filtration yielded higher in vitro fertilization rate in terms of cleavage rate compared to glass wool filtration and swim-up (control). In conclusion, cryopreserved Nili-Ravi buffalo sperm selected through Sephadex filtration showed improved quality and yielded better fertilization rates (cleavage rate) of in vitro matured/fertilized oocytes. Sephadex filtration could be a promising technique for use in in vitro fertilization in buffalo.


Assuntos
Búfalos , Separação Celular/veterinária , Filtração/veterinária , Espermatozoides/fisiologia , Animais , Separação Celular/métodos , Criopreservação/veterinária , Feminino , Fertilização in vitro/veterinária , Filtração/métodos , Vidro , Técnicas de Maturação in Vitro de Oócitos/veterinária , Masculino , Oócitos , Preservação do Sêmen/veterinária , Motilidade dos Espermatozoides
14.
Reprod Domest Anim ; 52(6): 992-997, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28660630

RESUMO

The study was designed to evaluate AndroMed® for the freezability and fertility of Nili-Ravi buffalo semen. Semen was collected from four adult Nili-Ravi buffalo (Bubalus bubalis) bulls for 3 weeks (replicate). Semen ejaculates from each buffalo bull were divided into three aliquots. One aliquot was used for evaluation of motility, plasma membrane integrity, livability, viability, DNA integrity and normal apical ridge. Remaining two aliquots were diluted (37°C; 50 × 106 spermatozoa/ml) in tris-citric egg yolk or AndroMed® extender and cryopreserved in 0.5 ml French straws. After thawing, per cent post-thaw motility (47.9 ± 0.8, 49.2 ± 1.7), plasma membrane integrity (44.4 ± 1.2, 46.8 ± 1.8) and normal apical ridge (81.4 ± 0.3, 83.2 ± 0.3) were recorded similar (p > .05) in tris-citric egg yolk and AndroMed® extender. Higher (p < .05) percentage of sperm livability (70.5 ± 1.4 and 64.4 ± 1.0), viability (67.5 ± 1.5 and 61.5 ± 0.6) and DNA integrity (97.0 ± 0.3 and 93.4 ± 0.21) were recorded in AndroMed® compared to tris-citric egg yolk post-thaw. Values for all the aforementioned spermatozoal quality parameters were observed lower (p < .05) in frozen-thawed compared to fresh semen irrespective of the experimental extenders. Fertility rates of buffalo semen did not differ (p > .05) either cryopreserved in tris-citric egg yolk or AndroMed® extender (45.5% vs. 49%). It is concluded that AndroMed® is capable in protecting the buffalo bull sperm during freeze-thawing process and can be adopted safely for routine use replacing the tris-citric egg yolk extender in artificial insemination programme.


Assuntos
Búfalos , Criopreservação/veterinária , Crioprotetores/farmacologia , Preservação do Sêmen/veterinária , Animais , Sobrevivência Celular/efeitos dos fármacos , Criopreservação/métodos , Dano ao DNA/efeitos dos fármacos , Feminino , Fertilidade/efeitos dos fármacos , Inseminação Artificial , Masculino , Gravidez , Sêmen/efeitos dos fármacos , Análise do Sêmen/veterinária , Preservação do Sêmen/métodos , Motilidade dos Espermatozoides/efeitos dos fármacos
15.
Acta Virol ; 61(2): 204-211, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28523927

RESUMO

Hepatitis C infection is a serious health issue worldwide caused by hepatitis C virus (HCV). There is an urgent need of search for new direct acting antiviral drugs due to the rapid development of drug resistance. The HCV NS5A protein is involved in creating resistance against antiviral therapy and there are also many reports that vitamin A deficiency is associated with non-responsiveness to antiviral treatment in HCV infected patients. So the present in silico study was aimed to find the relation between vitamin A deficiency and the NS5A protein's function in antiviral resistance. Structure of NS5A protein was predicted by using I-Tasser (Interactive Tasser). Previous data on conservative domains and dimer formation were confirmed by using a series of current computational methods. The structure was employed for molecular docking analysis to investigate the interaction of ligand BMS411 (4-[(5,5-dimethyl-8-phenyl-6H-naphthalene-2-carbonyl)amino]benzoic acid), a vitamin A related compound with NS5A protein. Docking analysis showed that retinoid BMS411 can bind to HCV NS5A protein and may act as inhibitor of this protein. The functionally interacting amino acid residues surrounding the ligand molecule were identified and were shown to be involved in the formation of binding pocket. The present study suggests that retinoids may play an important role in the improvement of the outcomes of antiviral therapy against HCV through interaction with NS5A and inhibition of this protein. It is of great importance to check and verify if other retinoids could act as NS5A inhibitors.


Assuntos
Antivirais/farmacologia , Benzoatos/farmacologia , Hepacivirus/metabolismo , Simulação de Acoplamento Molecular , Proteínas não Estruturais Virais/antagonistas & inibidores , Antivirais/química , Benzoatos/química , Domínio Catalítico , Regulação Viral da Expressão Gênica/efeitos dos fármacos , Regulação Viral da Expressão Gênica/fisiologia , Humanos , Conformação Proteica , Domínios Proteicos
16.
Cryo Letters ; 38(1): 43-50, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28376139

RESUMO

BACKGROUND: Semen from the Nili-Ravi buffalo bull, Bubalus bubalis, shows poor survival after freeze storage compared to bovine (Bos taurus and Bos indicus) semen. Freeze-susceptibility distinctions in these two genera have been attributed to differences in sperm membranes. MATERIALS AND METHODS: We measured the impact of protein preparations derived from a frost-resistant perennial grass, Lolium perenne, with ice recrystallization inhibition activity on the low temperature storage of B. bubalis semen. RESULTS: When the L. perenne preparations (0.1, 1, 10 µg/mL) were added to buffalo semen [2 ejaculates per bull (N=3) per replicate (r=3)] in Tris-citrate extender (50×106sperm mL-1), there was no impact on semen quality, as measured by sperm motility and plasma membrane integrity, after storage at 4 degree C (P>0.05). However, when semen supplemented with the grass proteins (0.1 and 1 µg mL-1) was evaluated after freezing and storage in liquid nitrogen for 24 h, post-thaw sperm progressive motility and plasma membrane integrity was higher (P<0.05) than in control samples. Post-thaw sperm viability and sperm acrosome integrity was similar (P > 0.05) to controls. CONCLUSION: The improvement in cryopreserved buffalo sperm progressive motility and plasma membrane integrity suggests that the use of these easily-made preparations may improve fertility after cryopreservation and offers the prospect of improved conception rates after artificial insemination with cryopreservation.


Assuntos
Criopreservação/métodos , Crioprotetores/farmacologia , Lolium , Extratos Vegetais/farmacologia , Preservação do Sêmen/métodos , Animais , Búfalos , Bovinos , Crioprotetores/química , Lolium/química , Masculino , Proteínas de Plantas/farmacologia , Espermatozoides/efeitos dos fármacos
17.
Mymensingh Med J ; 26(3): 635-641, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28919621

RESUMO

Hypertension is a chronic and debilitating disease. Its complications give rise to cardiovascular diseases, stroke in Postmenopausal women. Estrogen deficiency that develops during menopause is likely the etiological factor for development of hypertension in postmenopausal women. Increased incidence of cardiovascular diseases in postmenopausal women may be due to hypertension caused by lower level of estrogen hormone. The study was carried out to observe the association of hypertension with serum estrogen level in postmenopausal women. This cross sectional study was conducted in the Department of Physiology, Dhaka Medical College, Dhaka, during the period of January 2011 to December 2011. A total number of 90 female subjects were selected from different areas of Dhaka city. Among them, 60 postmenopausal women with age ranging from 50 to 60 years were taken as study group and 30 apparently healthy premenopausal women with age ranging from 20 to 30 years were included as control group for comparison. Systolic blood pressure and diastolic blood pressure were recorded in both groups. Serum estrogen level was estimated in order to assess the hormonal level of both groups. Data was analyzed by Unpaired Student's 't' test and Pearson's co-efficient (r) test as applicable. The value of systolic blood pressure was higher in postmenopausal women than those of premenopausal women and result was statistically significant. The level of diastolic blood pressure was also significantly (p<0.001) higher in postmenopausal women in comparison to those of premenopausal women. In postmenopausal women serum estrogen level was lower than premenopausal women and serum estrogen level showed negative correlation with systolic and diastolic blood pressure levels. All these correlation were statistically non significant. Present study revealed that there is association of hypertension with serum estrogen level in postmenopausal women.


Assuntos
Estrogênios , Hipertensão , Pós-Menopausa , Bangladesh , Estudos Transversais , Estrogênios/sangue , Feminino , Humanos , Hipertensão/sangue , Pessoa de Meia-Idade
18.
Mymensingh Med J ; 26(3): 483-489, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28919599

RESUMO

Hyperemesis gravidarum is the most severe form of nausea and vomiting in pregnancy with poor pregnancy outcome. Hormonal changes, psychological and immunological factors are attributed to the condition. Recently, prevalence of Helicobacter pylori among women with Hyperemesis gravidarum has been revealed. A descriptive, cross-sectional study was carried out at antenatal ward, Department of Obstetrics and Gynaecology, Mymensingh Medical College Hospital, Mymensingh among thirty-six purposively selected patients with Hyperemesis gravidarum to assess the clinic-biochemical profile. Data were collected through interview, physical examinations and laboratory investigations by using case record form. Statistical analyses were performed using SPSS version 20.0 for windows. Highest number 16(44.44%) of respondents were in age group 20 to 24 years with a mean of 23.81±4.55 years. Majority 29(80.56%) of the women had education less than 12 years, as many as 28(77.78%) women were housewives, and at least 14(38.89%) women had unplanned pregnancies. An overwhelming majority 29(80.56%) of women had their pregnancy duration between 8 to 12 weeks. At least 20(55.56%) of women were pregnant for first time, as many as 19(52.78%) women had duration of illness for 5 to 9 weeks, and all the women had remarkable weight loss. Cent per cent women were dehydrated, and appearance of 27(75.00%) women was ill-looking. Thyroid Stimulating Hormone (TSH), total leucocyte count and serum creatinine levels were normal for cent per cent women. As many as 15(41.67%) women had hypokalaemia, while 13(36.11%) had hyponatraemia and 3(8.33%) had hypochloraemia. Patient with Hyperemesis gravidarum often presents with ill-looking appearance, vomiting over 10 times a day, dehydration, remarkable loss of body weight and anaemia. Ketonuria, hyponatraemia, hypokalaemia and hypochloraemia are not associated with severity of illness.


Assuntos
Hiperêmese Gravídica , Adulto , Estudos Transversais , Escolaridade , Feminino , Humanos , Hiperêmese Gravídica/sangue , Hiperêmese Gravídica/epidemiologia , Paridade , Gravidez , Resultado da Gravidez , Centros de Atenção Terciária , Tireotropina
19.
Mymensingh Med J ; 26(1): 80-86, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-28260760

RESUMO

Hypertension is a chronic illness associated with high morbidity & mortality. A large number of antihypertensive drugs alone or in various combinations are available and physicians need to choose the most appropriate drug for a particular patient. The standard treatment guidelines and drug utilization studies at regular intervals help physicians to prescribe drugs rationally. The present study was conducted to evaluate the use of antihypertensive in hypertension with or without ischemic heart disease and diabetes mellitus at Department of Cardiology in Mymensingh Medical College Hospital, Mymensingh from July 2015 to October 2015. It was an observational type of descriptive cross sectional study. The study was performed among 400 hypertensive patients in Cardiology department in MMCH who received antihypertensive drug. Out of 400 hypertensive patients 67% were male and 33% were female. Maximum patients (54%) found in 40 - <60 years age group and ≤60 years age group (37.5%). Mean age of the patients was 55.02±12.47 years. Mean systolic BP was 146.74±28.28 and diastolic BP was 90.60±14.27mmHg. In overall prescription combination therapy (63.25%) was prescribed more frequently than mono-therapy (36.75%). In monotherapy ramipril was the most commonly prescribed (27.89%) antihypertensive drug and ARB was the most commonly prescribed group (37.41%). In our study 5 groups of antihypertensive were found (ARB, ACEI, BB, Diuretics, and CCB). In combination therapy 2-drugs combination were found most frequently (37.50%) and ACEI + Diuretics (23.72%) was the most common combination followed by ARB + Diuretics (12.25%), ACEI + BB (11.86%). Average number of antihypertensive drug per prescription was 1.9.


Assuntos
Anti-Hipertensivos , Hipertensão , Adulto , Idoso , Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea , Estudos Transversais , Quimioterapia Combinada , Feminino , Humanos , Hipertensão/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Centros de Atenção Terciária
20.
Nanotechnology ; 27(28): 285702, 2016 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-27251385

RESUMO

The paper reports the thermo-therapeutic applications of chitosan- and PEG-coated nickel ferrite (NiFe2O4) nanoparticles. In this study NiFe2O4 nanoparticles were synthesized by the co-precipitation method, tuning the particle size through heat treatment in the temperature range from 200-800 °C for 3 h. XRD and TEM analysis revealed that the the ultrafine nanoparticles were of size 2-58 nm. Crystallinity of the NiFe2O4 nanoparticles in the as-dried condition with the particle size ∼2-3 nm was confirmed from the presence of a lattice fringe in the HRTEM image. VSM measurements showed that a superparamagnetic/ferromagnetic transition occurs with increasing particle size, which was further confirmed by Mössbauer spectroscopy. The nickel ferrite nanoparticles with optimum particle size of 10 nm were then coated with materials commonly used for biomedical applications, i.e. chitosan and PEG, to form homogeneous suspensions. The hydrodynamic diameter and the polydispersity index (PDI) were analyzed by dynamic light scattering at the physiological temperature of 37 °C and found to be 187 nm and 0.21 for chitosan-coated nanoparticles and 285 nm and 0.32 for PEG-coated ones. The specific loss power of rf induction heating by the set-up for hyperthermia and r 2 relaxivity by the nuclear magnetic resonance were determined. The results of induction heating measurements showed that the temperature attained by the nanoparticles of size 10 nm and concentration of about 20 mg ml(-1) was >70 °C (for chitosan) and >64 °C (for PEG). It has been demonstrated that the required temperature for hyperthermia heating could be tuned by tuning the particle size, shape and magnetization and the concentration of solution. For other potential biomedical applications of the NiFe2O4 nanoparticle solution, e.g. magnetic resonance imaging, the NMR studies yielded the T 1 and T 2 relaxivities as 0.348 and 89 mM(-1) s(-1) respectively. The fact that the T 2 relaxivity is orders of magnitude higher than T 1 indicates that this is suitable as a T 2 contrast agent for magnetic resonance imaging.


Assuntos
Nanopartículas Metálicas , Quitosana , Compostos Férricos , Níquel
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