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1.
Pak J Med Sci ; 40(5): 918-921, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38827878

RESUMEN

Objective: In Pakistan, colon cancer ranks fourth in incidence, exhibiting survival rates of 90% to 14%, contingent on TNM staging and early detection. This research focuses on the demographic involvement and short-term outcomes of elective colon cancer resections at a newly established tertiary care cancer center utilizing laparoscopic procedures. Method: A retrospective analysis of elective laparoscopic colorectal resections at Shaukat Khanum Memorial Cancer Institute and Research Centre, Peshawar, from April 2021 to February 2022 was conducted. Out of 157 cases, 79 had colon cancer. Criteria included patients >18 years old with positive biopsies; consent non-providers were excluded. Statistical analysis employed descriptive statistics and cross-tabulations using SPSS-22. Results: The study encompassed biopsy-confirmed colon cancers in patients >18 years. 157 colorectal cases were performed, including 79 colon cancers. The sample comprised 61 males (77.2%) and 18 females (22.7%), mean age 42 years. Most patients (33%) were in the 36-45 age group. Majority were from KPK (69.6%), followed by Afghanistan (24%). Tumors were predominantly in the ascending colon (30.3%). Most were moderately differentiated (70.8%). Mean lymph node yield was 19.0, with 1.2% requiring open laparotomy. Post-discharge, one readmission occurred within 30 days. Mortality within 90 days was 2%, attributed to aspiration pneumonia and chemotherapy-related effects. Conclusions: Elective laparoscopic colonic surgery exhibits safety and efficacy in treating colon cancer. The study provides evidence of minimal morbidity and mortality, low readmission rates, and absence of anastomotic leaks. Hence, elective laparoscopic colonic surgery should be favored due to fewer post-operative complications and superior short-term outcomes. Larger studies on colon cancer are imperative for enhanced healthcare delivery.

2.
Microb Pathog ; 182: 106271, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37517745

RESUMEN

Epigenetics, a field of study focused on cellular gene regulation independent of DNA sequence alterations, encompasses DNA methylation, histone modification and microRNA modification. Epigenetics processes play a pivotal role in governing the life cycles of viruses, enabling their transmission, persistence, and maintenance with in host organisms. This review examines the epigenetics regulation of diverse virus including orthomoxyviruses, coronavirus, retroviridae, mononegavirales, and poxviruses among others. The investigation encompasses ten representative viruses from these families. Detailed exploration of the epigenetic mechanisms underlying each virus type, involving miRNA modification, histone modification and DNA methylation, sheds light on the intricate and multifaceted epigenetic interplay between viruses and their hosts. Furthermore, this review investigates the influence of these epigenetic processes on infection cycles, emphasizing the utilization of epigenetics by viruses such as Epstein-Barr virus and Human immunodeficiency virus (HIV) to regulate gene expression during chronic or latent infections, control latency, and transition to lytic infection. Finally, the paper explores the novel treatments possibilities stemming from this epigenetic understanding.


Asunto(s)
Infecciones por Virus de Epstein-Barr , Virus , Humanos , Herpesvirus Humano 4/genética , Interacciones Microbiota-Huesped , Epigénesis Genética , Virus/genética
3.
Int J Mol Sci ; 24(12)2023 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-37373089

RESUMEN

Trolox is a potent antioxidant and a water-soluble analog of vitamin E. It has been used in scientific studies to examine oxidative stress and its impact on biological systems. Trolox has been shown to have a neuroprotective effect against ischemia and IL-1ß-mediated neurodegeneration. In this study, we investigated the potential protective mechanisms of Trolox against a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced Parkinson's disease mouse model. Western blotting, immunofluorescence staining, and ROS/LPO assays were performed to investigate the role of trolox against neuroinflammation, the oxidative stress mediated by MPTP in the Parkinson's disease (PD) mouse model (wild-type mice (C57BL/6N), eight weeks old, average body weight 25-30 g). Our study showed that MPTP increased the expression of α-synuclein, decreased tyrosine hydroxylase (TH) and dopamine transporter (DAT) levels in the striatum and substantia nigra pars compacta (SNpc), and impaired motor function. However, Trolox treatment significantly reversed these PD-like pathologies. Furthermore, Trolox treatment reduced oxidative stress by increasing the expression of nuclear factor erythroid-2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1). Lastly, Trolox treatment inhibited the activated astrocytes (GFAP) and microglia (Iba-1), also reducing phosphorylated nuclear factor-κB, (p-NF-κB) and tumor necrosis factor-alpha (TNF-α) in the PD mouse brain. Overall, our study demonstrated that Trolox may exert neuroprotection on dopaminergic neurons against MPTP-induced oxidative stress, neuroinflammation, motor dysfunction, and neurodegeneration.


Asunto(s)
Trastornos Motores , Fármacos Neuroprotectores , Enfermedad de Parkinson , Animales , Ratones , Enfermedad de Parkinson/tratamiento farmacológico , Enfermedad de Parkinson/etiología , Enfermedad de Parkinson/metabolismo , 1-Metil-4-fenil-1,2,3,6-Tetrahidropiridina/efectos adversos , Enfermedades Neuroinflamatorias , Vitamina E/farmacología , Trastornos Motores/metabolismo , Sustancia Negra/metabolismo , Ratones Endogámicos C57BL , Tirosina 3-Monooxigenasa/metabolismo , Neuronas Dopaminérgicas/metabolismo , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/uso terapéutico , Fármacos Neuroprotectores/metabolismo , Estrés Oxidativo , Modelos Animales de Enfermedad
4.
Int J Vitam Nutr Res ; 92(5-6): 301-310, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32686990

RESUMEN

ß-Carotene exhibits antioxidant and hepatoprotective activities via a multitude of biochemical mechanisms. However, the action mechanism involved in antioxidant and anti-inflammatory effects of this carotene in chronic liver diseases is not fully understood. In the present investigation, we have attempted to outline a plausible mechanism of ß-carotene action against liver fibrosis in albino Wistar rats. To induce hepatic fibrosis, diethylnitrosamine (DEN) was administered in experimental rats for two weeks. DEN treated rats were divided into four groups, wherein each group comprised of five rats. ß-Carotene supplement attenuated DEN-induced elevation in LFT markers (P < 0.05); averted depletion of glycogen (24%, P < 0.05) and, increased nitrite (P < 0.05), hydroxyproline (~67%, P < 0.05) and collagen levels (~65%, P < 0.05). Confocal microscopy of tissue sections stained with picrosirius red revealed accrued collagen in DEN-administered group, which was found to be reduced by ß-carotene supplementation. Furthermore, ß-carotene decreased the expression of iNOS/NOS-2 and NF-κB, as revealed by immunohistochemistry and Western immunoblotting. Collectively, these results demonstrate that ß-carotene mitigates experimental liver fibrosis via inhibition of iNOS and NF-κB in-vivo. Thus, ß-carotene may be suggested as a possible nutraceutical to curb experimental liver fibrosis.


Asunto(s)
Dietilnitrosamina , FN-kappa B , Animales , Antiinflamatorios/farmacología , Antioxidantes/farmacología , Dietilnitrosamina/metabolismo , Dietilnitrosamina/toxicidad , Glucógeno/metabolismo , Glucógeno/farmacología , Glucógeno/uso terapéutico , Hidroxiprolina/metabolismo , Hidroxiprolina/farmacología , Hidroxiprolina/uso terapéutico , Inflamación/inducido químicamente , Inflamación/tratamiento farmacológico , Hígado/metabolismo , Cirrosis Hepática/inducido químicamente , Cirrosis Hepática/metabolismo , Cirrosis Hepática/prevención & control , FN-kappa B/metabolismo , FN-kappa B/farmacología , FN-kappa B/uso terapéutico , Nitritos/metabolismo , Nitritos/farmacología , Nitritos/uso terapéutico , Ratas , Ratas Wistar , beta Caroteno/metabolismo , beta Caroteno/farmacología , beta Caroteno/uso terapéutico
5.
Int J Mol Sci ; 23(11)2022 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-35682768

RESUMEN

Traumatic brain injury (TBI) signifies a major cause of death and disability. TBI causes central nervous system (CNS) damage under a variety of mechanisms, including protein aggregation, mitochondrial dysfunction, oxidative stress, and neuroinflammation. Astrocytes and microglia, cells of the CNS, are considered the key players in initiating an inflammatory response after injury. Several evidence suggests that activation of astrocytes/microglia and ROS/LPO have the potential to cause more harmful effects in the pathological processes following traumatic brain injury (TBI). Previous studies have established that lupeol provides neuroprotection through modulation of inflammation, oxidative stress, and apoptosis in Aß and LPS model and neurodegenerative disease. However, the effects of lupeol on apoptosis caused by inflammation and oxidative stress in TBI have not yet been investigated. Therefore, we explored the role of Lupeol on antiapoptosis, anti-inflammatory, and antioxidative stress and its potential mechanism following TBI. In these experiments, adult male mice were randomly divided into four groups: control, TBI, TBI+ Lupeol, and Sham group. Western blotting, immunofluorescence staining, and ROS/LPO assays were performed to investigate the role of lupeol against neuroinflammation, oxidative stress, and apoptosis. Lupeol treatment reversed TBI-induced behavioral and memory disturbances. Lupeol attenuated TBI-induced generation of reactive oxygen species/lipid per oxidation (ROS/LPO) and improved the antioxidant protein level, such as nuclear factor erythroid 2-related factor 2 (Nrf2) and heme-oxygenase 1 (HO-1) in the mouse brain. Similarly, our results indicated that lupeol treatment inhibited glial cell activation, p-NF-κB, and downstream signaling molecules, such as TNF-α, COX-2, and IL-1ß, in the mouse cortex and hippocampus. Moreover, lupeol treatment also inhibited mitochondrial apoptotic signaling molecules, such as caspase-3, Bax, cytochrome-C, and reversed deregulated Bcl2 in TBI-treated mice. Overall, our study demonstrated that lupeol inhibits the activation of astrocytes/microglia and ROS/LPO that lead to oxidative stress, neuroinflammation, and apoptosis followed by TBI.


Asunto(s)
Lesiones Traumáticas del Encéfalo , Enfermedades Neurodegenerativas , Animales , Lesiones Traumáticas del Encéfalo/metabolismo , Modelos Animales de Enfermedad , Inflamación/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Factor 2 Relacionado con NF-E2/metabolismo , Neuroglía/metabolismo , Estrés Oxidativo , Triterpenos Pentacíclicos , Especies Reactivas de Oxígeno/farmacología
6.
Environ Res ; 194: 110683, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33450236

RESUMEN

The toxic emissions from coal combustion associated with domestic winter heating requirements are an important public health issue. Waste cooking oil (WCO) holds promise as a means of reducing pollutant emissions thereby improving human health with the co-benefit of decreasing climate-forcing gas emissions by avoiding the combustion of mineral coal. With an annual production of ~2.17 Mt of WCO in Northern China, it could be used to meet the winter heating demand of ~3.25 million rural households, offsetting ~9.83 Mt of raw coal consumption. Through the adoption of coal-to-WCO shift in rural regions of 15 provinces, approximately 15.0%, 15.6%, 15.9% and 13.7%, respectively of CO, PM2.5, SO2 and NOX emissions would be eliminated. It is estimated that such a change would remove the respective contributions of these pollutants to the premature deaths of respectively, 63,400, 29,300, 173,00 and 31,300 rural residents. Such a positive health impact on the labor cohort would reduce the loss of labor supply and work time, as well as producing billions of RMB in economic benefits. WCO-based heating technology has the same effect on the reduction of GWC100 value as other modern energy carriers while also being cheaper and sustainable, long term. Reducing household emissions by substituting raw coal with green energy is a vital strategy to support pathways for sustainable environment design. The results of this work for the coal-to-WCO shift can reinforce the support for coal phase-out in China.


Asunto(s)
Contaminantes Atmosféricos , Carbón Mineral , Contaminantes Atmosféricos/análisis , China , Carbón Mineral/análisis , Culinaria , Calefacción , Humanos , Material Particulado/análisis
7.
Int J Mol Sci ; 22(1)2020 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-33396372

RESUMEN

The receptor for advanced glycation end products (RAGE), a pattern recognition receptor signaling event, has been associated with several human illnesses, including neurodegenerative diseases, particularly in Alzheimer's disease (AD). Vanillic acid (V.A), a flavoring agent, is a benzoic acid derivative having a broad range of biological activities, including antioxidant, anti-inflammatory, and neuroprotective effects. However, the underlying molecular mechanisms of V.A in exerting neuroprotection are not well investigated. The present study aims to explore the neuroprotective effects of V.A against lipopolysaccharides (LPS)-induced neuroinflammation, amyloidogenesis, synaptic/memory dysfunction, and neurodegeneration in mice brain. Behavioral tests and biochemical and immunofluorescence assays were applied. Our results indicated increased expression of RAGE and its downstream phospho-c-Jun n-terminal kinase (p-JNK) in the LPS-alone treated group, which was significantly reduced in the V.A + LPS co-treated group. We also found that systemic administration of LPS-injection induced glial cells (microglia and astrocytes) activation and significantly increased expression level of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-KB) and secretion of proinflammatory cytokines including tumor necrosis factor alpha (TNF-α), interleukin-1 ß (IL1-ß), and cyclooxygenase (COX-2). However, V.A + LPS co-treatment significantly inhibited the LPS-induced activation of glial cells and neuroinflammatory mediators. Moreover, we also noted that V.A treatment significantly attenuated LPS-induced increases in the expression of AD markers, such as ß-site amyloid precursor protein (APP)-cleaving enzyme 1 (BACE1) and amyloid-ß (Aß). Furthermore, V.A treatment significantly reversed LPS-induced synaptic loss via enhancing the expression level of pre- and post-synaptic markers (PSD-95 and SYP), and improved memory performance in LPS-alone treated group. Taken together; we suggest that neuroprotective effects of V.A against LPS-induced neurotoxicity might be via inhibition of LPS/RAGE mediated JNK signaling pathway; and encourage future studies that V.A would be a potential neuroprotective and neurotherapeutic candidate in various neurological disorders.


Asunto(s)
Encéfalo/efectos de los fármacos , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Gliosis/tratamiento farmacológico , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Lipopolisacáridos/toxicidad , Fármacos Neuroprotectores/farmacología , Ácido Vanílico/farmacología , Animales , Encéfalo/metabolismo , Encéfalo/patología , Gliosis/inducido químicamente , Gliosis/metabolismo , Gliosis/patología , Proteínas Quinasas JNK Activadas por Mitógenos/genética , Masculino , Ratones , Ratones Endogámicos C57BL
8.
J Pak Med Assoc ; 70(3): 457-460, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32207425

RESUMEN

OBJECTIVE: To investigate the association of emotional intelligence with academic self-efficacy and gender difference among undergraduate students. METHODS: The survey-based study was conducted at the Institute of Clinical Psychology, University of Karachi, Karachi, from January 2016 to October 2017, and comprised undergraduate students of either gender aged 16-25 years from different academic institutions. Data was collected using a demographic form, Schutte Emotional Intelligence Scale and the Academic Self Efficacy Scale. Data scrutiny and scoring was done according to the relevant manuals, and analysis was done using SPSS 17. RESULTS: Of the 400 subjects, 206(51.5%) were females and 194(48.5%) were males. The overall mean age was 21.28±2.12 years. Emotion perception, emotion utilisation, manage emotion with self and with others were significant predictors of academic self-efficacy (p<0.05 each). Gender difference was significant on all variables (p<0.05). CONCLUSIONS: Emotional intelligence was found to play a significant role in promoting academic selfefficacy among undergraduate students.


Asunto(s)
Éxito Académico , Educación de Pregrado en Medicina , Inteligencia Emocional , Autoeficacia , Estudiantes de Medicina , Correlación de Datos , Estudios Transversales , Demografía , Regulación Emocional , Femenino , Humanos , Masculino , Pakistán , Factores Sexuales , Estudiantes de Medicina/psicología , Estudiantes de Medicina/estadística & datos numéricos , Adulto Joven
9.
Toxicol Ind Health ; 35(8): 548-557, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31370753

RESUMEN

Metal oxide nanoparticles (NPs) have widespread uses ranging from nanoelectronics to nanotherapeutics. Because of their expanding industrial applications, a better understanding of their toxicity is needed. So far, limited reports are available on chromium oxide NPs (Cr2O3 NPs) toxicity. In this work, Cr2O3 NPs were synthesized and characterized in a sequential manner using X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, and transmission electron microscopy. Dose- and time-dependent toxicity assessment of Cr2O3 NPs was carried out in Wistar rats by examining liver function biomarkers, tissue histopathology, micronuclei (MN) formation, and chromosomal aberrations (CAs) in bone marrow along with sperm abnormalities. The results of this study demonstrated typical XRD and FTIR patterns of Cr2O3 NPs with a size of approximately 23.47 nm. Animals exposed to Cr2O3 NPs, exhibited a significant increase in aspartate transaminase, alanine transaminase, alkaline phosphatase, gamma glutamyltransferase, and total bilirubin, signifying liver injury. Histopathology data also supported the marked alterations in the liver biochemistry of NPs-exposed animals. Further, an increase in the frequency of MN, CA, and sperm abnormalities suggested Cr2O3 NPs-mediated genotoxicity. It is, therefore, suggested that possible safety issues of Cr2O3 NPs should be addressed promptly with limited future use in occupational settings.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Compuestos de Cromo/toxicidad , Aberraciones Cromosómicas/inducido químicamente , Nanopartículas del Metal/toxicidad , Administración Oral , Animales , Médula Ósea/efectos de los fármacos , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Compuestos de Cromo/administración & dosificación , Relación Dosis-Respuesta a Droga , Hígado/efectos de los fármacos , Hígado/patología , Masculino , Nanopartículas del Metal/administración & dosificación , Pruebas de Micronúcleos , Ratas , Ratas Wistar , Espermatozoides/efectos de los fármacos
11.
Appl Microbiol Biotechnol ; 102(22): 9449-9470, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30219952

RESUMEN

Cancer is a devastating disease and remains a significant cause of mortality and morbidity in both developed and developing countries. Although there are large number of drugs that can be used for the treatment of cancer, the problem is selective and specific killing of cancerous cells without harming the normal cells. There are some biological barriers to potential drug delivery in cancer cells like hepatic, renal, abnormal vasculature, dense extracellular matrix, and high interstitial fluid pressure. The physicochemical characteristics of nanoparticles (NPs) such as size, shape, and surface charge may also have significant effects on tumor penetration. NPs coated with drug can be used to overcome these biological barriers to enhance targeted delivery. This literature survey encompasses the biological barriers to potential drug delivery in cancer cells, elaborate on designing strategies to enhance NPs penetration and distribution inside the tumor interstitium. Scientists are now doing great efforts to design next-generation of nanomedicines (NMs) that need to be better targeted with high specificity and efficacy to kill cancer cells. These challenges need to be overcome through collaborations among academia, pharmaceutical industries, and regulatory agencies to eradicate this global menace. Furthermore, this review article has critically discussed the recent developments, controversies, challenges, emerging concepts, and future perspectives in cancer NMs.


Asunto(s)
Antineoplásicos/administración & dosificación , Antineoplásicos/química , Sistemas de Liberación de Medicamentos/métodos , Nanomedicina/métodos , Neoplasias/tratamiento farmacológico , Animales , Sistemas de Liberación de Medicamentos/instrumentación , Humanos , Nanomedicina/instrumentación , Nanopartículas/química
12.
Physiol Mol Biol Plants ; 24(5): 845-856, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30150859

RESUMEN

Plants retain the preceding abiotic stress memory that may aid in attainment of tolerance to subsequent stresses. This study was conducted to evaluate the influence of terminal drought memory (drought priming) and seed priming in improving drought tolerance in wheat (Triticum aestivum L.). During first growing season, wheat was planted in field under optimal (well-watered) and drought stress imposed at reproductive stage (BBCH growth stage 49) until maturity (BBCH growth stage 83). Seeds collected from both sources were subjected to hydropriming or osmopriming (with 1.5% CaCl2 solution); while, dry seed was taken as control. Treated and control seeds, from both sources, were sown in soil filled pots. After the completion of seedling emergence, pots were maintained at 50% water holding capacity (drought) or 100% water holding capacity (well-watered). Drought stress suppressed the plant growth (2-44%), perturbed water relations (1-18%) and reduced yield (192%); however, osmolytes accumulation (3-14%) and malondialdehyde contents (26-29%) were increased under drought. The crop raised from the seeds collected from terminal drought stressed plants had better growth (5-63%), improved osmolyte accumulation (13-45%), and lower lipid peroxidation (3%) than the progeny of well-watered crop. Seed priming significantly improved the crop performance under drought stress as compared to control. However, osmopriming was more effective than hydropriming in this regard as it improved leaf area (9-43%), tissue water status (2-47%), osmolytes accumulation (6-48%) and grain yield (14-79%). In conclusion, terminal drought induced modifications in seed composition and seed priming improved transgenerational drought tolerance through improvement in tissue water status and osmolytes accumulation, and decrease in lipid peroxidation.

13.
Toxicol Ind Health ; 33(12): 911-921, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29069986

RESUMEN

Chromium oxide nanoparticles (Cr2O3 NPs) have a wide range of applications in industry. They are used as pigments, catalysts, wear-resistant or high-temperature-resistant coating material and are used in liquid crystal displays. In view of ever escalating use of NPs, risk assessment becomes obligatory to ensure the safety of both human health and the ecosystem. The present study was designed and conducted to evaluate biochemical changes and histopathological alterations in kidneys and brain of rats, following exposure to Cr2O3 NPs. Male Wistar rats were divided into low-dose (50 µg/100 g body weight (bwt) groups and high-dose (200 µg/100 g bwt) groups. Each group type received oral administration of Cr2O3 NPs for multiple durations (single dosing, once daily for 7 days and once daily for 14 days, respectively). According to our data, this allotment presented a meaningful picture of NPs behaviour in different scenarios. In the kidneys and brain of Cr2O3 NPs-exposed animals, reactive oxygen species (ROS) production caused a significant increase in malondialdehyde (MDA) concentration along with a significant decrease in superoxide dismutase and glutathione levels, as compared to controls. Histopathological changes in these organs confirmed cellular injury and functional damage due to exposure to Cr2O3 NPs. In this study, we have distinguished pathological alterations consequent to deleterious oxidative stress due to enhanced ROS generation after Cr2O3 NPs exposure.


Asunto(s)
Encéfalo/efectos de los fármacos , Compuestos de Cromo/toxicidad , Riñón/efectos de los fármacos , Nanopartículas del Metal/toxicidad , Animales , Antioxidantes/metabolismo , Encéfalo/patología , Química Encefálica/efectos de los fármacos , Riñón/química , Riñón/patología , Peroxidación de Lípido/efectos de los fármacos , Masculino , Estrés Oxidativo/efectos de los fármacos , Ratas , Ratas Wistar , Pruebas de Toxicidad
14.
Adsorp Sci Technol ; 34(1): 3-12, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27840542

RESUMEN

The goal of the eighth industrial fluid properties simulation challenge was to test the ability of molecular simulation methods to predict the adsorption of organic adsorbates in activated carbon materials. In particular, the eighth challenge focused on the adsorption of perfluorohexane in the activated carbon BAM-109. Entrants were challenged to predict the adsorption in the carbon at 273 K and relative pressures of 0.1, 0.3, and 0.6. The predictions were judged by comparison to a benchmark set of experimentally determined values. Overall good agreement and consistency were found between the predictions of most entrants.

15.
Adsorp Sci Technol ; 34(1): 13-41, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27840543

RESUMEN

The primary goal of the eighth industrial fluid properties simulation challenge was to test the ability of molecular simulation methods to predict the adsorption of organic adsorbates in activated carbon materials. The challenge focused on the adsorption of perfluorohexane in the activated carbon standard BAM-P109 (Panne and Thünemann 2010). Entrants were challenged to predict the adsorption of perfluorohexane in the activated carbon at a temperature of 273 K and at relative pressures of 0.1, 0.3, and 0.6. The relative pressure (P/Po) is defined as that relative to the bulk saturation pressure predicted by the fluid model at a given temperature (273 K in this case). The predictions were judged by comparison to a set of experimentally determined values, which are published here for the first time and were not disclosed to the entrants prior to the challenge. Benchmark experimental studies, described herein, were also carried out and provided to entrants in order to aid in the development of new force fields and simulation methods to be employed in the challenge. These studies included argon, carbon dioxide, and water adsorption in the BAM-P109 activated carbon as well as X-ray diffraction, X-ray microtomography, photoelectron spectroscopy, and atomic emission spectroscopy studies of BAM-P109. Several concurrent studies were carried out for the BAM-P108 activated carbon (Panne and Thünemann 2010). These are included in the current manuscript for comparison.

16.
J Food Sci Technol ; 53(8): 3340-3348, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27784928

RESUMEN

Ultrasonication has been suggested as a new promising technique to improve the quality of meat and other meat products. In this study ultrasonication at low frequency (20 kHz) was carried out to investigate the effect on structural and biochemical properties of myofibril proteins. The possible implications between ultrasonication-induced structural changes and gelation properties were also investigated. Structural changes were investigated by ATPase activity, SDS-PAGE, circular dichroism and fluorescence spectroscopy. Microstructural changes in heat induced gels were observed by SEM and water holding capacity was determined by centrifugation. Ultrasonic treatment for 30 min significantly reduced the Ca2+-ATPase activity. Moreover significant change in structure of proteins at secondary level, as indicated by marked decrease in α-helicity, was observed. Marginal change in fluorescence at 10 min was followed by significant increase at 20 and 30 min reflecting exposure of hydrophobic residues on surface during unfolding. Microstructural analyses of gels showed marked improvement in regular three dimensional network at 20 and 30 min of sonication. WHC at 20 min and 30 min were significantly higher than control. Our results suggest that ultrasonication at low frequency (20 kHz) can prove beneficial for improving functional properties of meat and meat products.

17.
Pharm Biol ; 2014 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-24405044

RESUMEN

Abstract Context: Altered vitamin B12 levels have been correlated with hepatotoxicity; however, further evidence is required to establish its protective role. Objective: To evaluate the effects of vitamin B12 supplement in protecting N'-nitrosodimethylamine (NDMA)-induced hepatic fibrosis in Wistar rats. Materials and methods: Hepatic fibrosis was induced by administering NDMA in doses of 10 mg/kg body weight thrice a week for 21 days. Another group received equal doses (10 mg/kg body weight) of vitamin B12 subsequent to NDMA treatment. Animals from either group were sacrificed weekly from the start of the treatment along with their respective controls. Progression of hepatic fibrosis, in addition to the effect of vitamin B12, was assessed biochemically for liver function biomarkers, liver glycogen, hydroxyproline (HP) and B12 reserves along with histopathologically by hematoxylin and eosin (H & E) as well immunohistochemical staining for α-SMA expression. Results and discussion: Elevation in the levels of aminotransferases, SALP, total bilirubin and HP was observed in NDMA treated rats, which was concomitant with remarkable depletion in liver glycogen and B12 reserves (p < 0.05). Liver biopsies also demonstrated disrupted lobular architecture, collagen amassing and intense fibrosis by NDMA treatment. Immunohistochemical staining showed the presence of activated stellate cells that was dramatically increased up to day 21 in fibrotic rats. Following vitamin B12 treatment, liver function biomarkers, glycogen contents and hepatic vitamin B12 reserves were restored in fibrotic rats, significantly. Vitamin B12 administration also facilitated restoration of normal liver architecture. Conclusion: These findings provide interesting new evidence in favor of protective role for vitamin B12 against NDMA-induced hepatic fibrosis in rats.

18.
Sci Rep ; 14(1): 11041, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38744905

RESUMEN

Recent results demonstrate the dynamical peculiarities of the quantum chaos within the hybrid systems by chaotic parameters and probe the pattern formation under the influence of condensation. The complex dynamic behavior of the considered systems was determined with numerical simulation and presented an efficient technique that studied fractional systems comprising chaos-coherence fractions. The findings divulge the peculiar association between the coherence structure and the correlations at finite relative momenta. Thus the present study helps to explore the partially chaos hybrid systems in order to stimulate the experimental applications of nonlinear phenomena. The coherent-chaotic parameters can be measured by examining the chaos peculiarities that possess explicit relations with the condensations to demonstrate the environs of the physical systems. We investigate the influence of the multiplicities, chaos, momentum and temperature of the nonlinear system on the coherent-chaotic normalized correlations. The chaotic parameters are suppressed considerably with the coherence fraction and it appears numerically zero at maximum condensation and one at ideal chaos emissions. We procure that the meaningful parameters decrease significantly with the multiplicity of the nonlinear systems and increase with the momentum in the specified regimes. The identical multiplicity leads to contemplating the coherence and thus the normalized chaotic parameters within its spectacular influences exhibit significance worth contemplating in earnest. The findings underscore the significance of cogitating correlations in deciphering the nonlinear system characteristics and bestowing extraordinary perceptiveness into the convoluted essence of complex systems. The contemplated methodology can be applied to evaluating and analyzing the nonlinear systems and such an innovative approach computes the problems of celestial mechanics, heartbeats and chemical reactions in engineering and medical fields.

19.
PeerJ Comput Sci ; 10: e1925, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38660206

RESUMEN

This article introduces a recognition system for handwritten text in the Pashto language, representing the first attempt to establish a baseline system using the Pashto Handwritten Text Imagebase (PHTI) dataset. Initially, the PHTI dataset underwent pre-processed to eliminate unwanted characters, subsequently, the dataset was divided into training 70%, validation 15%, and test sets 15%. The proposed recognition system is based on multi-dimensional long short-term memory (MD-LSTM) networks. A comprehensive empirical analysis was conducted to determine the optimal parameters for the proposed MD-LSTM architecture; Counter experiments were used to evaluate the performance of the proposed system comparing with the state-of-the-art models on the PHTI dataset. The novelty of our proposed model, compared to other state of the art models, lies in its hidden layer size (i.e., 10, 20, 80) and its Tanh layer size (i.e., 20, 40). The system achieves a Character Error Rate (CER) of 20.77% as a baseline on the test set. The top 20 confusions are reported to check the performance and limitations of the proposed model. The results highlight complications and future perspective of the Pashto language towards the digital transition.

20.
J Mass Spectrom ; 59(2): e5002, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38311469

RESUMEN

In this study, low-energy cesium (Cs+ ) ion-induced sputtered fragmentation of poly allyl diglycol carbonate (PADC) was investigated using mass spectrometry. The collision-induced dissociation mechanism revealed emission of various fragments, including monoatomic (H- , C1 - , O1 - ), diatomic (C2 - ), and multiatomic (C3 - , CO2 - , C2 O2 - , C3 O2 - ) species within the Cs+ ion energy range of 1-5 keV. The anion current of these fragments exhibited a linear increase with rising incident Cs+ ion energy, indicating a corresponding rise in fragment abundance. Analysis of normalized yield indicated that at 1 keV incident energy, the dominant fragment was monoatomic hydrogen (H- ), followed by diatomic carbon (C2 - ), monoatomic carbon (C1 - ), and monoatomic oxygen (O1 - ). Although C2 - remained dominant up to 5 keV, other fragments exhibited varying normalized yields at different ion energy steps. The sputter yield estimation revealed that monoatomic hydrogen (H- ) and diatomic carbon (C2 - ) exhibited the highest yields, increasing exponentially beyond 3 keV, while multiatomic fragments like C3 - , CO2 - , C2 O2 - , and C3 O2 - displayed the lowest yields. The sputter dissociation mechanism pointed to dehydrogenation, chain scission, and bond breakage as the primary processes during low-energy Cs+ ion impact. Postsputtering Scanning Electron Mircoscope (SEM) micrographs show craters, pits, and micropores on the PADC surface, indicating significant surface degradation. X-ray Diffraction (XRD) spectra exhibited reduced diffraction intensity, while Fourier Transform Infrared Spectroscopy (FTIR) analysis indicated the absence of molecular bands in the IR spectrum, confirming extensive surface damage due to Cs+ ion-induced sputtering.

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