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1.
Phys Chem Chem Phys ; 26(5): 4166-4173, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38230486

RESUMEN

This paper provides a detailed analysis of pure CsPbIBr2 and 4% Ce-doped CsPbIBr2 perovskite films, emphasizing their structural, optical and photovoltaic properties. X-ray diffraction confirms a predominant cubic perovskite phase in both samples, with Ce doping leading to the increased crystal size (21 nm to 32 nm). UV-vis spectroscopy reveals a reduced bandgap energy (2.2 eV to 2.1 eV) with Ce doping. Dielectric constant analysis indicates the enhanced permittivity of the Ce-doped sample, crucial for solar-cell light trapping. Energy band structure analysis demonstrates improved photovoltaic cell performance with Ce doping, yielding higher open-circuit voltage, short-circuit current, and efficiency (9.71%) compared to pure CsPbIBr2 (8.02%). Ce doping mitigates electron-hole recombination, enhancing cell stability, electron affinity, and power output. This research underscores the potential of cost-effective, efficient, and stable CsPbIBr2 perovskite solar cells.

2.
Phys Chem Chem Phys ; 26(15): 12210-12218, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38592224

RESUMEN

The spin coating method was used to deposit MAPbI2Br films on FTO-glass substrates. Zn2+ (zinc) doping was used for these films at intensity rates of 2% and 4%, respectively. XRD analysis proved that MAPbI2Br films had a cubic structure and a crystalline character. 2% Zn doping into the MAPbI2Br film had a modest large grain size (38.09 nm), Eg (1.95 eV), high refractive index (2.66), and low extinction coefficient (1.67), according to XRD and UV-vis analyses. To facilitate and enhance carrier transit, at contacts as well as throughout the bulk material, the perovskite's trap-state densities decreased. The predicted MAPbI2Br valence and conduction band edges are -5.44 and -3.52, respectively. The conduction band (CB) edge of the film that was exposed to Zn atoms has been pressed towards the lower value, assembly it a better material for solar cells. EIS is particularly useful for understanding charge carrier transport, recombination mechanisms, and the influence of different interfaces within the device structure. Jsc is 11.09 mA cm-2, Voc is 1.09, PCE is 9.372% and FF is 0.777. The cell made with the 2% Zn doped into the MAPbI2Br film demonstrated a superior device.

3.
Trop Anim Health Prod ; 55(2): 88, 2023 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-36808487

RESUMEN

Feeding of dietary energy sources has been extensively studied in dairy cows but not well described in dairy buffaloes. The objective of this study was to evaluate the effect of prepartum dietary energy sources on productive and reproductive performance in Nili Ravi buffaloes (n = 21). The buffaloes were offered isocaloric (1.55 Mcal/kg DM NEL (net energy for lactation)) glucogenic (GD), lipogenic (LD), and mixed diet (MD) during 63 days prepartum and maintained (1.27 Mcal/kg DM NEL) at lactation diet (LCD) during 14 weeks postpartum. Effects of dietary energy sources and week on animals were analyzed with the mixed model. The DMI, BCS, and body weights remained similar during the pre- and postpartum periods. The prepartum diets did not affect birth weight, blood metabolites, milk yield, and composition. The GD tended to early uterine involution, more follicle numbers, and early follicle formation. The prepartum feeding of dietary energy source had a similar effect on first estrus expression, days open, conception rate, pregnancy rate, and calving interval. So, it could be concluded that prepartum feeding of an isocaloric dietary energy source had a similar effect on the performance of buffaloes.


Asunto(s)
Bison , Búfalos , Embarazo , Femenino , Bovinos , Animales , Dieta/veterinaria , Reproducción , Lactancia , Periodo Posparto , Leche
4.
BMC Genomics ; 19(1): 258, 2018 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-29661134

RESUMEN

BACKGROUND: Prolongation of superstimulatory treatment appears to be associated with a greater superovulatory response and with greater oocyte maturation in cattle. A genome-wide bovine oligo-microarray was used to compare the gene expression of granulosa cells collected from ovarian follicles after differing durations of the growing phase induced by exogenous FSH treatment. Cows were given a conventional (4-day) or long (7-day) superstimulatory treatment (25 mg FSH im at 12-h intervals; n = 6 per group), followed by prostaglandin treatment with last FSH and LH treatment 24 h later. Granulosa cells were harvested 24 h after LH treatment. RESULTS: The expression of 416 genes was down-regulated and 615 genes was up-regulated in the long FSH group compared to the conventional FSH group. Quantification by RT-PCR of 7 genes (NTS, PTGS2, PTX3, RGS2, INHBA, CCND2 and LRP8) supported the microarrays data. Multigene bioinformatic analysis indicates that markers of fertility and follicle maturity were up-regulated in the long FSH group. CONCLUSION: Using the large gene expression dataset generated by the genomic analysis and our previous associated with the growth phase and gene expression changes post LH, we can conclude that a prolonged FSH-induced growing phase is associated with transcriptomic characteristics of greater follicular maturity and may therefore be more appropriate for optimizing the superovulatory response and developmental competence of oocytes in cattle.


Asunto(s)
Bovinos/genética , Hormona Folículo Estimulante/farmacología , Células de la Granulosa/metabolismo , Transcriptoma/efectos de los fármacos , Animales , Bovinos/metabolismo , Femenino , Hormona Folículo Estimulante/administración & dosificación , Líquido Folicular/química , Perfilación de la Expresión Génica , Células de la Granulosa/efectos de los fármacos , Reacción en Cadena en Tiempo Real de la Polimerasa , Superovulación
5.
Crit Rev Food Sci Nutr ; 58(5): 858-876, 2018 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-27646175

RESUMEN

For a long time, food engineers have been trying to describe the physical phenomena that occur during food processing especially drying. Physics-based theoretical modeling is an important tool for the food engineers to reduce the hurdles of experimentation. Drying of food is a multi-physics phenomenon such as coupled heat and mass transfer. Moreover, food structure is multi-scale in nature, and the microstructural features play a great role in the food processing specially in drying. Previously simple macroscopic model was used to describe the drying phenomena which can give a little description about the smaller scale. The multiscale modeling technique can handle all the phenomena that occur during drying. In this special kind of modeling approach, the single scale models from bigger to smaller scales are interconnected. With the help of multiscale modeling framework, the transport process associated with drying can be studied on a smaller scale and the resulting information can be transferred to the bigger scale. This article is devoted to discussing the state of the art multi-scale modeling, its prospect and challenges in the field of drying technology. This article has also given some directions to how to overcome the challenges for successful implementation of multi-scale modeling.


Asunto(s)
Desecación , Manipulación de Alimentos/métodos , Modelos Teóricos
6.
Arch Virol ; 162(7): 1833-1843, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28283816

RESUMEN

The poultry industry has emerged as one of the largest and fastest growing public sectors in the developed and developing countries. Unfortunately, this industry is under a major threat from diseases that are viral (Newcastle disease, infectious bursal disease, influenza, hydropericardium syndrome), bacterial (colibacillosis, pasteurellosis, salmonellosis, mycoplasmosis), parasitic (coccidiosis, histoplasmosis) or nutritional (dyschondroplasia, osteoporosis). Among these diseases, hydropericardium syndrome (HPS) is one of the important emerging diseases occurring in the specific areas of the world where broilers (chickens) are reared under intensive conditions. HPS was first observed in 1987 at Angara Goth, an area near Karachi, Pakistan, where broilers are raised. Since then, HPS has been reported in many countries of the world. From these reported cases, an adenovirus that was either isolated from or visualized electron microscopically in the liver of affected broilers has been implicated in the syndrome. The syndrome has been reproduced by inoculation of isolated fowl adenovirus (FAdV) strains, and hence, the syndrome is also called infectious hydropericardium syndrome. To our knowledge, HPS has not been observed in humans, so it is not considered a zoonotic disease, but it is of economic importance and causes huge losses to the poultry industry. Efforts have been made to develop conventional vaccines against this disease, which were formulated from infected liver homogenate. Formalin-inactivated liver organ vaccines have failed to protect the poultry industry. Hence, there is a dire need to develop a suitable vaccine to combat this disease. Currently, recombinant vaccine candidates are being developed by using molecular biology and biotechnological approaches for the prevention and control of infectious diseases, including HPS. Therefore, it is suggested that the immunogenicity of these recombinant proteins should be evaluated for their use as subunit vaccines.


Asunto(s)
Infecciones por Adenoviridae/veterinaria , Adenovirus A Aviar/fisiología , Enfermedades de las Aves de Corral/prevención & control , Vacunas Virales/inmunología , Infecciones por Adenoviridae/prevención & control , Infecciones por Adenoviridae/virología , Animales , Aves de Corral , Enfermedades de las Aves de Corral/virología
7.
Ir Med J ; 110(1): 499, 2017 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-28657276

RESUMEN

Venous Thromboembolic (VTE) events in hospitalised patients are associated with significant mortality and morbidity and a major economic burden on the health service. It is well established in the literature that active implementation of a mandatory risk assessment tool and thromboprophylaxis policy reduces the incidence of hospital associated thrombosis (HAT). This study examines the utilization of a VTE risk assessment tool and thromboprophylaxis (TP) policy in Irish hospitals that manage acute admissions. A national survey was distributed to forty acute hospitals throughout Ireland. The response rate was 78% (31/40). The results showed that only 26% (n=8/31) of acute hospitals in Ireland have a local implemented TP policy. Six (75%) of these eight had a risk assessment tool in conjunction with the TP policy. All respondents who did not report to have a TP policy and risk assessment tool agreed that they should implement VTE prevention policy at their hospital. Based on the data from this survey and evidence from the effectiveness of the VTE prevention programme introduced in the United Kingdom, there is a need for a national risk assessment and thromboprophylaxis policy in Ireland. This change in practice would have the potential to prevent or reduce the morbidity and mortality associated with hospital acquired thrombosis.


Asunto(s)
Medición de Riesgo , Tromboembolia Venosa/prevención & control , Encuestas de Atención de la Salud/estadística & datos numéricos , Implementación de Plan de Salud , Humanos , Irlanda , Reino Unido
8.
Ir Med J ; 110(4): 542, 2017 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-28665081

RESUMEN

Venous thromboembolism (VTE) is a major cause of preventable morbidity and mortality in hospitalized patients. In spite of guidelines, VTE prophylaxis continues to be underutilised, and hospital acquired thrombosis (HAT) continues to be a problem. This study was conducted to estimate the incidence of HAT in a tertiary referral centre and to examine whether VTE risk assessment and thromboprophylaxis (TP) were implemented. Patients 18 years and above, with a radiologically-confirmed acute VTE during the study period of 15 weeks were included. Acute VTE was diagnosed in 100 patients and HAT was diagnosed in 48. There were 12,024 admissions over the study period, therefore the incidence of HAT was 0.4%. TP was prescribed in only 35% of patients, and 65% did not receive any or appropriate TP. Hospitals without active implementation of a formal risk assessment tool and TP policy are likely to continue to have increased incidence of HAT.


Asunto(s)
Trombosis/epidemiología , Tromboembolia Venosa/epidemiología , Adulto , Humanos , Incidencia , Radiografía , Medición de Riesgo , Factores de Riesgo , Centros de Atención Terciaria , Trombosis/diagnóstico por imagen , Trombosis/etiología , Trombosis/prevención & control , Tromboembolia Venosa/diagnóstico por imagen , Tromboembolia Venosa/prevención & control
9.
Ir Med J ; 110(4): 547, 2017 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-28665086

RESUMEN

Evidence based guidelines are effective in reducing incidence of venous thromboembolism (VTE) which is associated with morbidly, mortality and economic burden. This study aimed to identify the proportion of inpatients who had a VTE risk assessment (RA) performed and who received thromboprophylaxis (TP), in Cork University Hospital. There was no structured RA tool at the time; information was obtained from medical and drug charts to ascertain if a RA was performed. Patients were then RA by researchers and stratified as per NICE guidelines and the proportion who received TP was calculated. One thousand and nineteen inpatients were screened. Risk was documented in 24% of cases. TP was prescribed in 43.2% of inpatients. Following application of a RA tool >80% were at high risk of VTE with low risk of bleeding with TP prescription in 46.3% of inpatients. A national collaborative effort should be encouraged to develop a standardized approach for safe RA of inpatients and prescription of TP for prevention of HAT.


Asunto(s)
Anticoagulantes/administración & dosificación , Tromboembolia Venosa/prevención & control , Estudios Transversales , Hospitalización , Humanos , Medición de Riesgo , Factores de Riesgo , Tromboembolia Venosa/epidemiología , Tromboembolia Venosa/etiología
10.
Biologicals ; 44(1): 19-23, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26558992

RESUMEN

Fowl adenovirus-4 is an infectious agent causing Hydropericardium syndrome in chickens. Adenovirus are non-enveloped virions having linear, double stranded DNA. Viral genome codes for few structural and non structural proteins. 100K is an important non-structural viral protein. Open reading frame for coding sequence of 100K protein was cloned with oligo histidine tag and expressed in Escherichia coli as a fusion protein. Nucleotide sequence of the gene revealed that 100K gene of FAdV-4 has high homology (98%) with the respective gene of FAdV-10. Recombinant 100K protein was expressed in E. coli and purified by nickel affinity chromatography. Immunization of chickens with recombinant 100K protein elicited significant serum antibody titers. However challenge protection test revealed that 100K protein conferred little protection (40%) to the immunized chicken against pathogenic viral challenge. So it was concluded that 100K gene has 2397 bp length and recombinant 100K protein has molecular weight of 95 kDa. It was also found that the recombinant protein has little capacity to affect the immune response because in-spite of having an important role in intracellular transport & folding of viral capsid proteins during viral replication, it is not exposed on the surface of the virus at any stage.


Asunto(s)
Infecciones por Adenoviridae , Adenoviridae , Proteínas de la Cápside , Pollos , Genes Virales/inmunología , Inmunización , Enfermedades de las Aves de Corral , Adenoviridae/genética , Adenoviridae/inmunología , Infecciones por Adenoviridae/genética , Infecciones por Adenoviridae/inmunología , Infecciones por Adenoviridae/prevención & control , Infecciones por Adenoviridae/veterinaria , Infecciones por Adenoviridae/virología , Animales , Proteínas de la Cápside/genética , Proteínas de la Cápside/inmunología , Proteínas de la Cápside/farmacología , Pollos/inmunología , Pollos/virología , Clonación Molecular , Enfermedades de las Aves de Corral/genética , Enfermedades de las Aves de Corral/inmunología , Enfermedades de las Aves de Corral/prevención & control , Enfermedades de las Aves de Corral/virología
11.
Br Poult Sci ; 57(4): 566-75, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27108741

RESUMEN

The present study was conducted to evaluate the role of extruded flaxseed (EFS) and α-tocopherol acetate (ATA) for the enhancement of polyunsaturated fatty acids ratio (PUFA) over saturated fatty acids (SFA) in broiler meat as a source of healthier meat. A total of 96 one-d-old Cobb 550 broilers were randomly divided into 8 treatments with three replicates having 4 birds in each. EFS (extruded at 155°C) at 100, 150 and 200 g/kg alone and in combination with ATA at 200 mg/kg were supplemented through normal feed from the third week onward. During the 6-week growth period, body weight gain (BWG), feed intake (FI), feed conversion ratio (FCR) and mortality were recorded. At slaughter, weight of liver, heart and kidney and fat content in breast and leg meat were measured. Fatty acid profiles in breast and leg meat were developed to estimate the PUFA to SFA ratio. The results revealed that FI and FCR changed significantly in all groups and BWG increased in all the supplemented groups. The weight of liver, kidney and heart increased more in the supplemented group containing the maximum level of EFS with ATA compared with single supplementation of EFS. The fat content in breast and leg meat decreased as the inclusion level of EFS increased. The level was low in leg meat compared with breast meat. Mortality decreased in all supplemented groups. The PUFA to SFA ratio was significantly higher in leg meat (3.23) compared with breast meat (1.81) and the study therefore indicates that ATA and EFS supplementation could be used to improve the PUFA to SFA ratio in broiler meat.


Asunto(s)
Pollos/fisiología , Dieta/veterinaria , Suplementos Dietéticos , Lino/química , Carne/análisis , Valor Nutritivo , alfa-Tocoferol/metabolismo , Alimentación Animal/análisis , Animales , Pollos/crecimiento & desarrollo , Ácidos Grasos/análisis , Ácidos Grasos Insaturados/análisis , Carne/normas , Distribución Aleatoria , Semillas/química , alfa-Tocoferol/administración & dosificación
13.
RSC Adv ; 14(8): 5440-5448, 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38348293

RESUMEN

Lead-free halide double perovskite (LFHDP) Cs2AgBiBr6 has emerged as a promising alternative to traditional lead-based perovskites (LBPs), offering notable advantages in terms of chemical stability and non-toxicity. However, the efficiency of Cs2AgBiBr6 solar cells faces challenges due to their wide bandgap (Eg). As a viable strategy to settle this problem, we consider optimization of the optical and photovoltaic properties of Cs2AgBiBr6 by Gallium (Ga) substitution. The synthesized Cs2Ag0.95Ga0.05BiBr6 is rigorously characterized by means of X-ray diffraction (XRD), UV-vis spectroscopy, and solar simulator measurements. XRD analysis reveals shifts in peak positions, indicating changes in the crystal lattice due to Ga substitution. The optical analysis demonstrates a reduction in the Eg, leading to improvement of the light absorption within the visible spectrum. Importantly, the Cs2Ag0.95Ga0.05BiBr6 solar cell exhibits enhanced performance, as evidenced by higher values of open circuit voltage (Voc), short-circuit current (Jsc), and fill factor (FF), which are 0.94 V, 6.01 mA cm-2, and 0.80, respectively: this results in an increased power conversion efficiency (PCE) from 3.51% to 4.52%. This research not only helps to overcome film formation challenges, but also enables stable Cs2Ag0.95Ga0.05BiBr6 to be established as a high-performance material for photovoltaic applications. Overall, our development contributes to the advancement of environmentally friendly solar technologies.

14.
Heliyon ; 10(4): e25591, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38370257

RESUMEN

The current study focuses the nanocomposites of Ag/WO3 was synthesized via hydrothermal method and extract of Aloe-vera gel was used. Various characterization techniques were used for the analysis of Ag/WO3 nanocomposites which includes SEM (scanning electron microscope), EDX (Energy dispersive spectroscopy), XRD (X-ray diffraction), FTIR (Fourier transform infrared), UV (ultraviolet-visible-spectroscopy) to tell about elemental composition, shape and crystalline structure, band gap, functional group. The presence of composition of elements O, W, Ag in Ag/WO3 nanocomposites was confirmed through EDX spectrum. The hexagonal crystal structure and the border peaks in Ag/WO3 nanocomposites were examined through XRD spectra. The Anti-oxidant activity was synthesized by using (DPPH) free Radical in Ag/WO3 nanocomposites. The outcomes of present study exhibited an excellent anti-oxidant activity and also indicated the reduction of stabilized free radical DPPH analysis using Aloe vera extract. The result revealed that the anti-oxidant activity of Ag/WO3 nanocomposites is essential for biomedical application and various industries.

15.
Front Chem ; 12: 1361082, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38741671

RESUMEN

SARS-CoV-2 infection affects and modulates serum as well as hematological parameters. However, whether it modifies these parameters in the existing disease conditions, which help in the erection of specific treatments for the disease, is under investigation. Here, we aimed to determine whether serum and hematological parameters alteration in various diseases, diabetes mellitus (DM), hypertension (HTN), ischemic heart disease (IHD) and myocardial infarction (MI) conditions correlate and signal SARS-CoV-2 infection, which could be used as a rapid diagnosis tool for SARS-CoV-2 infection in disease conditions. To assess the projected goals, we collected blood samples of 1,113 male and female patients with solo and multiple disease conditions of DM/HTN/IHD/MI with severe COVID-19, followed by biochemical analysis, including COVID-19 virus detection by RT-qPCR. Furthermore, blood was collected from age-matched disease and healthy individuals 502 and 660 and considered as negative control. In our results, we examined higher levels of serum parameters, including D-dimer, ferritin, hs-CRP, and LDH, as well as hematological parameters, including TLC in sole and multiple diseases (DM/HTN/IHD/MI) conditions compared to the control subjects. Besides, the hematological parameters, including Hb, RBC, and platelet levels, decreased in the patients. In addition, we found declined levels of leukocyte count (%), lymphocyte (%), monocyte (%), and eosinophil (%), and elevated level of neutrophil levels (%) in all the disease patients infected with SARS-CoV-2. Besides, NLR and NMR ratios were also statistically significantly (p < 0.05) high in the patients with solo and multiple disease conditions of DM/HTN/IHD/MI infected with the SARS-CoV-2 virus. In conclusion, rapid alteration of sera and hematological parameters are associated with SARS-CoV-2 infections, which could help signal COVID-19 in respective disease patients. Moreover, our results may help to improve the clinical management for the rapid diagnosis of COVID-19 concurrent with respective diseases.

16.
Reproduction ; 146(2): 181-91, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23740080

RESUMEN

Microarray analysis was used to compare the gene expression of granulosa cells from dominant follicles with that of those after superstimulatory treatment. Cows were allocated randomly to two groups (superstimulation and control, n=6/group). A new follicular wave was induced by ablation of follicles ≥5 mm in diameter, and a progesterone-releasing device controlled internal drug release (CIDR) was placed in the vagina. The superstimulation group was given eight doses of 25 mg FSH at 12-h intervals starting from the day of wave emergence (day 0), whereas the control group was not given FSH treatment. Both groups were given prostaglandin F2α twice, 12 h apart, on day 3 and the CIDR was removed at the second injection; 25 mg porcine luteinizing hormone (pLH) was given 24 h after CIDR removal, and cows were ovariectomized 24 h later. Granulosa cells were collected for RNA extraction, amplification, and microarray hybridization. A total of 190 genes were downregulated and 280 genes were upregulated. To validate the microarray results, five genes were selected for real-time PCR (NTS, FOS, THBS1, FN1, and IGF2). Expression of four genes increased significantly in the three different animals tested (NTS, FOS, THBS1, and FN1). The upregulated genes are related to matrix remodeling (i.e. tissue proliferation), disturbance of angiogenesis, apoptosis, and oxidative stress response. We conclude that superstimulation treatment i) results in granulosa cells that lag behind in maturation and differentiation (most of the upregulated genes are markers of the follicular growth stage), ii) activates genes involved with the NFE2L2 oxidative stress response and endoplasmic reticulum stress response, and iii) disturbs angiogenesis.


Asunto(s)
Apoptosis/efectos de los fármacos , Estrés del Retículo Endoplásmico/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , Células de la Granulosa/efectos de los fármacos , Inducción de la Ovulación/veterinaria , Estrés Oxidativo/efectos de los fármacos , Administración Intravaginal , Animales , Bovinos , Cruzamientos Genéticos , Preparaciones de Acción Retardada , Femenino , Fármacos para la Fertilidad Femenina/administración & dosificación , Fármacos para la Fertilidad Femenina/farmacología , Hormona Folículo Estimulante/administración & dosificación , Hormona Folículo Estimulante/farmacología , Perfilación de la Expresión Génica/veterinaria , Células de la Granulosa/metabolismo , Inyecciones Intramusculares , Factor 2 Relacionado con NF-E2/biosíntesis , Factor 2 Relacionado con NF-E2/genética , Factor 2 Relacionado con NF-E2/metabolismo , Progesterona/administración & dosificación , Progesterona/farmacología , ARN Mensajero/metabolismo , Distribución Aleatoria
17.
Genet Mol Res ; 12(2): 1106-18, 2013 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-23661436

RESUMEN

DNA methylation is a fundamental epigenetic mechanism in regulating the expression of genes controlling crucial cell functions in cancer development. Gene silencing via CpG island methylation/demethylation in the promoter region is one of the mechanisms by which different genes are inactivated/activated in human cancers. Tissue inhibitor of metalloproteinase-2 (TIMP-2) is known to antagonize matrix metalloproteinase (MMP) activity and to suppress tumor growth, angiogenesis, invasion, and metastasis. TIMP-2 expression has been found to be both upregulated and downregulated in various cancers. The inconsistent TIMP-2 expression and unclear epigenetic regulation lead us to investigate its role in colorectal cancer in the presence of a methylating agent. Highly invasive human colorectal cells SW-620 were treated with the methyl donor S-adenosylmethionine (SAM) and its effect was evaluated by cell proliferation, cell cycle, invasion and migration assay. The ability of SAM to down regulate a panel of activated prometastatic, angiogenesis and growth- and cell cycle-regulatory genes was evaluated using end-point and real-time PCR. Treatment of SW-620 with SAM diminished cell proliferation and altered cell cycle kinetic G2/M phase cell cycle arrest. An in vitro matrigel invasion assay of SAM-treated cells showed a significant reduction in the invasive potential compared to untreated SW-620 cells. Treatment of SW-620 cells with SAM resulted in activation of TIMP-2 and inhibition of the expression of genes such as MMP (MMP-2, MT1-MMP), urokinase plasminogen activator, and vascular endothelial growth factors. The level of expression of tumor suppressor and apoptotic genes was not significantly higher compared to the untreated control. No changes in the levels of expression of genes (growth and cell cycle regulator), such as TGF-ß, Smad2, Smad4, and p21 were observed. Our data support the hypothesis that TIMP-2, along with other prometastatic genes, is hypomethylated and expressed differently in colorectal cancer. Further in-depth analysis is warranted to confirm the promoter region CpG methylation pattern of the TIMP-2 gene.


Asunto(s)
Neoplasias Colorrectales/genética , S-Adenosilmetionina/farmacología , Inhibidor Tisular de Metaloproteinasa-2/genética , Apoptosis/efectos de los fármacos , Apoptosis/genética , Ciclo Celular/efectos de los fármacos , Ciclo Celular/genética , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Neoplasias Colorrectales/metabolismo , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Inhibidor Tisular de Metaloproteinasa-2/metabolismo
18.
Bangladesh Med Res Counc Bull ; 39(1): 6-10, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23923404

RESUMEN

The study was performed to compare the blood glucose lowering effect of Swietenia mahagoni seeds with an oral antidiabetic drug, rosiglitazone in experimentally induced diabetic rats. Twentyfour healthy Long Evans Norwegian strain of rats were included in the study and divided into four groups (A, B, C and D) comprising 6 rats each. Group A (control group) received standard rat food for 14 days. Diabetes was induced by a single intraperitoneal administration of alloxan 120 mg/kg body weight in Group B, C and D. Group B was given standard food for 10 days and considered as diabetic control. Group C and D were treated with ethanolic extract of Swietenia mahagoni seeds 1000 mg/kg and rosiglitazone 10 mg/kg orally respectively. Administration of ethanolic extract of Swietenia mahagoni seeds in group C and rosiglitazone in group D produced a significant reduction in blood glucose level as compared to diabetic control (group B). Histological examination of pancreas showed destruction of beta cells in Islets of pancreas in group B whereas retaining of islets and few degranulations of beta cells of pancreas found in group C and group D. The observations and results of the present study provide information that ethanolic extract of Swietenia mahagoni seeds has hypoglycaemic effect in experimentally induced diabetic rats which requires further investigation.


Asunto(s)
Glucemia/efectos de los fármacos , Diabetes Mellitus Experimental/tratamiento farmacológico , Meliaceae , Fitoterapia , Tiazolidinedionas/uso terapéutico , Aloxano/administración & dosificación , Animales , Bangladesh , Diabetes Mellitus Experimental/inducido químicamente , Femenino , Hipoglucemiantes/uso terapéutico , Masculino , Extractos Vegetales/uso terapéutico , Ratas , Ratas Long-Evans , Rosiglitazona , Semillas
19.
Heliyon ; 9(11): e21702, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38027903

RESUMEN

Recently, all inorganic double perovskites have drawn a lot of interest as promising solar materials. The optical, structural, thermoelectric, electronic, and mechanical properties of double halide perovskites A2LiGaI6 (A = Cs, Rb) are explored via first-principles calculations with the WIEN2k code, using GGA PBEsol and TB-mBJ potentials. The majority of perovskite materials utilized in the highest-performing solar cells have bandgaps ranging between 1.48 and 1.62 eV. The compounds A2LiGaI6 (A = Cs, Rb) have a direct bandgap of 1.51 eV and 1.55 eV, respectively, and are expected to be useful in solar cells. The optical study shows that there are large absorption bands in the visible region, as determined by the dielectric constant, absorption, and other dependent factors. Their potential for use in solar cells is increased by their absorption in the visible part. The BoltzTraP code has been used to perform thermoelectric studies to assess the electrical, thermal conductivities, and Seebeck coefficient. They are important for construction of thermoelectric generators that harvest heat energy because of their high figure of merit and incredibly low thermal conductivity of lattice at ambient temperature. Furthermore, by examining the spectroscopic limit maximum efficiency, up to 30 % efficiency is predicted for both compositions, which paves the way for the applicability of them in solar energy conversion.

20.
ACS Omega ; 8(20): 17667-17681, 2023 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-37251181

RESUMEN

Photocatalytic degradation of dyes has been the subject of extensive study due to its low cost, eco-friendly operation, and absence of secondary pollutants. Copper oxide/graphene oxide (CuO/GO) nanocomposites are emerging as a new class of fascinating materials due to their low cost, nontoxicity, and distinctive properties such as a narrow band gap and good sunlight absorbency. In this study, copper oxide (CuO), graphene oxide (GO), and CuO/GO were synthesized successfully. X-ray diffractometer (XRD) and Fourier transform infrared (FTIR) spectroscopy confirm the oxidation and production of GO from the graphene of lead pencil. According to the morphological analysis of nanocomposites, CuO nanoparticles of sizes ≤20 nm on the GO sheets were evenly adorned and distributed. Nanocomposites of different CuO:GO ratios (1:1 up to 5:1) were applied for the photocatalytic degradation of methyl red (MR). CuO:GO(1:1) nanocomposites achieved 84% MR dye removal, while CuO:GO(5:1) nanocomposites achieved the highest value (95.48%). The thermodynamic parameters of the reaction for CuO:GO(5:1) were evaluated using the Van't Hoff equation and the activation energy was found to be 44.186 kJ/mol. The reusability test of the nanocomposites showed high stability even after seven cycles. CuO/GO catalysts can be used in the photodegradation of organic pollutants in wastewater at room temperature due to their excellent properties, simple synthesis process, and low cost.

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