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1.
Network ; : 1-21, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38975754

RESUMEN

Cloud computing is an on-demand virtual-based technology to develop, configure, and modify applications online through the internet. It enables the users to handle various operations such as storage, back-up, and recovery of data, data analysis, delivery of software applications, implementation of new services and applications, hosting websites and blogs, and streaming of audio and video files. Thereby, it provides us many benefits although it is backlashed due to problems related to cloud security like data leakage, data loss, cyber attacks, etc. To address the security concerns, researchers have developed a variety of authentication mechanisms. This means that the authentication procedure used in the suggested method is multi-levelled. As a result, a better QKD method is offered to strengthen cloud security against different types of security risks. Key generation for enhanced QKD is based on the ABE public key cryptography approach. Here, an approach named CPABE is used in improved QKD. The Improved QKD scored the reduced KCA attack ratings of 0.3193, this is superior to CMMLA (0.7915), CPABE (0.8916), AES (0.5277), Blowfish (0.6144), and ECC (0.4287), accordingly. Finally, this multi-level authentication using an improved QKD approach is analysed under various measures and validates the enhancement over the state-of-the-art models.

2.
Pol J Radiol ; 89: e368-e377, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39139256

RESUMEN

Purpose: To detect foot ulcers in diabetic patients by analysing thermal images of the foot using a deep learning model and estimate the effectiveness of the proposed model by comparing it with some existing studies. Material and methods: Open-source thermal images were used for the study. The dataset consists of two types of images of the feet of diabetic patients: normal and abnormal foot images. The dataset contains 1055 total images; among these, 543 are normal foot images, and the others are images of abnormal feet of the patient. The study's dataset was converted into a new and pre-processed dataset by applying canny edge detection and watershed segmentation. This pre-processed dataset was then balanced and enlarged using data augmentation, and after that, for prediction, a deep learning model was applied for the diagnosis of an ulcer in the foot. After applying canny edge detection and segmentation, the pre-processed dataset can enhance the model's performance for correct predictions and reduce the computational cost. Results: Our proposed model, utilizing ResNet50 and EfficientNetB0, was tested on both the original dataset and the pre-processed dataset after applying edge detection and segmentation. The results were highly promising, with ResNet50 achieving 89% and 89.1% accuracy for the two datasets, respectively, and EfficientNetB0 surpassing this with 96.1% and 99.4% accuracy for the two datasets, respectively. Conclusions: Our study offers a practical solution for foot ulcer detection, particularly in situations where expert analysis is not readily available. The efficacy of our models was tested using real images, and they outperformed other available models, demonstrating their potential for real-world application.

3.
Clin Exp Immunol ; 214(2): 197-208, 2023 12 12.
Artículo en Inglés | MEDLINE | ID: mdl-37498307

RESUMEN

The interplay between platelets and leukocytes contributes to the pathogenesis of inflammation, thrombosis, and cardiovascular diseases (CVDs) in type 2 diabetes (T2D). Our recent studies described alpha-ketoglutarate (αKG), a Krebs cycle intermediate metabolite as an inhibitor to platelets and leukocytes activation by suppressing phosphorylated-Akt (pAkt) through augmentation of prolyl hydroxylase-2 (PHD2). Dietary supplementation with a pharmacological concentration of αKG significantly inhibited lung inflammation in mice with either SARS-CoV-2 infection or exposed to hypoxia treatment. We therefore investigated if αKG supplementation could suppress hyperactivation of these blood cells and reduce thromboinflammatory complications in T2D. Our study describes that dietary supplementation with αKG (8 mg/100 g body wt. daily) for 7 days significantly reduced the activation of platelets and leukocytes (neutrophils and monocytes), and accumulation of IL1ß, TNFα, and IL6 in peripheral blood of T2D mice. αKG also reduced the infiltration of platelets and leukocytes, and accumulation of inflammatory cytokines in lungs by suppressing pAkt and pP65 signaling. In a cross-sectional investigation, our study also described the elevated platelet-leukocyte aggregates and pro-inflammatory cytokines in circulation of T2D patients. T2D platelets and leukocytes showed an increased aggregation and thrombus formation in vitro. Interestingly, a pre-incubation of T2D blood samples with octyl αKG significantly suppressed the activation of these blood cells and ameliorated aggregate/thrombus formation in vitro. Thus, suggesting a potential therapeutic role of αKG against inflammation, thrombosis, and CVDs in T2D.


Asunto(s)
Enfermedades Cardiovasculares , Diabetes Mellitus Tipo 2 , Trombosis , Humanos , Ratones , Animales , Ácidos Cetoglutáricos/metabolismo , Estudios Transversales , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Activación Plaquetaria , Inflamación/metabolismo , Leucocitos/patología , Plaquetas/patología , Trombosis/tratamiento farmacológico , Trombosis/etiología , Enfermedades Cardiovasculares/patología , Citocinas/metabolismo , Suplementos Dietéticos
4.
IUBMB Life ; 2023 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-38063433

RESUMEN

Diabetes, a chronic metabolic disorder disrupting blood sugar regulation, has emerged as a prominent silent pandemic. Uncontrolled diabetes predisposes an individual to develop fatal complications like cardiovascular disorders, kidney damage, and neuropathies and aggravates the severity of treatable infections. Escalating cases of Type 1 and Type 2 diabetes correlate with a global upswing in diabetes-linked mortality. As a growing global concern with limited preventive interventions, diabetes necessitates extensive research to mitigate its healthcare burden and assist ailing patients. An altered immune system exacerbated by chronic hyperinflammation heightens the susceptibility of diabetic individuals to microbial infections, including notable viruses like SARS-CoV-2, dengue, and influenza. Given such a scenario, we scrutinized the literature and compiled molecular pathways and signaling cascades related to immune compartments in diabetics that escalate the severity associated with the above-mentioned viral infections in them as compared to healthy individuals. The pathogenesis of these viral infections that trigger diabetes compromises both innate and adaptive immune functions and pre-existing diabetes also leads to heightened disease severity. Lastly, this review succinctly outlines available treatments for diabetics, which may hold promise as preventive or supportive measures to effectively combat these viral infections in the former.

5.
Medicina (Kaunas) ; 59(10)2023 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-37893466

RESUMEN

Background and Objectives: Curcumin, derived from Curcuma longa, is a well-known traditional medicinal compound recognized for its therapeutic attributes. Nevertheless, its efficacy is hampered by limited bioavailability, prompting researchers to explore the application of nanoemulsion as a potential alternative. Materials and Methods: This study delves into the antihypertensive effects of curcumin nanoemulsion (SNEC) by targeting the renin-angiotensin-aldosterone system (RAAS) and oxidative stress in deoxycorticosterone acetate (DOCA) salt-induced hypertensive rats. To gauge the cardio-protective impact of SNEC in DOCA salt-induced hypertension, molecular docking was undertaken, uncovering curcumin's high affinity and adept binding capabilities to the active site of angiotensin-converting enzyme (ACE). Additionally, the investigation employed uninephrectomized rats to assess hemodynamic parameters via an AD instrument. Serum ACE, angiotensin II, blood urea nitrogen (BUN), and creatinine levels were quantified using ELISA kits, while antioxidant parameters were evaluated through chemical assays. Result: The outcomes of the molecular docking analysis revealed robust binding of curcumin to the ACE active site. Furthermore, oral administration of SNEC significantly mitigated systolic, diastolic, and mean arterial blood pressure in contrast to the DOCA-induced hypertensive group. SNEC administration also led to a reduction in left ventricular end-diastolic pressure (LVEDP) and an elevation in the maximum rate of left ventricular pressure rise (LV (dP/dt) max). Moreover, SNEC administration distinctly lowered serum levels of ACE and angiotensin II compared to the hypertensive DOCA group. Renal markers, including serum creatinine and BUN, displayed a shift toward normalized levels with SNEC treatment. Additionally, SNEC showcased potent antioxidant characteristics by elevating reduced glutathione, catalase, and superoxide dismutase levels, while decreasing the concentration of thiobarbituric acid reactive substances. Conclusions: Collectively, these findings underscore that curcumin nanoemulsion exerts noteworthy cardio-protective effects through ACE activity inhibition and remarkable antioxidant properties.


Asunto(s)
Curcumina , Acetato de Desoxicorticosterona , Hipertensión , Ratas , Animales , Antioxidantes/farmacología , Antioxidantes/uso terapéutico , Curcumina/farmacología , Curcumina/uso terapéutico , Acetato de Desoxicorticosterona/efectos adversos , Angiotensina II/efectos adversos , Simulación del Acoplamiento Molecular , Ratas Wistar , Antihipertensivos/uso terapéutico , Presión Sanguínea
6.
Pol J Radiol ; 88: e445-e454, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37808172

RESUMEN

Purpose: To detect tuberculosis (TB) at an early stage by analyzing chest X-ray images using a deep neural network, and to evaluate the efficacy of proposed model by comparing it with existing studies. Material and methods: For the study, an open-source X-ray images were used. Dataset consisted of two types of images, i.e., standard and tuberculosis. Total number of images in the dataset was 4,200, among which, 3,500 were normal chest X-rays, and the remaining 700 X-ray images were of tuberculosis patients. The study proposed and simulated a deep learning prediction model for early TB diagnosis by combining deep features with hand-engineered features. Gabor filter and Canny edge detection method were applied to enhance the performance and reduce computation cost. Results: The proposed model simulated two scenarios: without filter and edge detection techniques and only a pre-trained model with automatic feature extraction, and filter and edge detection techniques. The results achieved from both the models were 95.7% and 97.9%, respectively. Conclusions: The proposed study can assist in the detection if a radiologist is not available. Also, the model was tested with real-time images to examine the efficacy, and was better than other available models.

7.
Am J Ind Med ; 63(10): 902-906, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32803802

RESUMEN

BACKGROUND: The Indian hair and beauty salon industry is growing rapidly due to the demand for beauty and personal care services and products. Workers in the industry are vulnerable to several occupational factors such as chemicals, confined space, and poor ventilation. Chemicals in the products used are known or suspected to cause allergies, respiratory, neurological and reproductive health problems and cancer. METHODS: The present study was carried out to determine the factors associated with the occurrence of respiratory morbidity among hair and beauty salon workers of Udupi taluk, Karnataka, India. A total of 240 salon workers were recruited for the study. A semistructured, interviewer-led questionnaire was used to collect data. Peak expiratory flow rate (PEFR) was done using a JSB peak flow meter. RESULTS: The frequency of respiratory morbidity among participating beauty salon workers was 19%. Men reported respiratory symptoms more frequently than women. Receiving training on work materials and practices was a significant protective factor (odds ratio = 0.3; 95% confidence interval: 0.1-0.7) for the occurrence of respiratory morbidity. The mean observed PEFR in these workers was significantly lower than their predicted values. While 61.2% of the workers were using some form of personal protective equipment, only 4% of workers used a mask or respiratory protection. CONCLUSION: Hair and beauty salon workers are at risk of developing respiratory morbidity potentially from harmful exposures and lack of effective control measures at the workplace.


Asunto(s)
Industria de la Belleza/estadística & datos numéricos , Enfermedades Profesionales/epidemiología , Exposición Profesional/efectos adversos , Salud Laboral/estadística & datos numéricos , Trastornos Respiratorios/epidemiología , Adulto , Femenino , Humanos , India/epidemiología , Masculino , Enfermedades Profesionales/etiología , Exposición Profesional/análisis , Ápice del Flujo Espiratorio , Trastornos Respiratorios/etiología , Factores de Riesgo
8.
Bioorg Chem ; 87: 667-678, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30953886

RESUMEN

Meagre and suboptimal therapeutic response along with the side effect profile associated with the existing anticancer therapy have necessitated the development of new therapeutic modalities to curb this disease. Bearing in mind the current scenario, a series of 1,2,3-triazole linked 3-(1,3-diphenyl-1H-pyrazol-4-yl)acrylates was synthesized following a multi-step reaction scheme. Initial screening for anticancer potential was done by in vitro sulforhodamine B assay against four human cancer cell lines- MCF-7 (breast), A549 (Lung) and HCT-116 and HT-29 (Colon). On evaluation, several compounds showed promising growth inhibition against all the cell lines, particularly compounds 6e, 6f and 6n. Among them, compound 6f displayed IC50 values of 1.962, 3.597, 1.764 and 4.496 µM against A549, HCT-116, MCF-7 and HT-29 cell lines respectively. Furthermore, the apoptosis inducing potential of the compounds was determined by Hoechst staining and DNA fragmentation assay. Colony formation inhibition assay was also carried out to determine the long term cytotoxic potential of the molecules. Moreover, compounds 6e, 6f and 6n were also evaluated for anti-inflammatory activity by protein albumin denaturation assay and red blood cell membrane stabilizing assay.


Asunto(s)
Acrilatos/farmacología , Antiinflamatorios no Esteroideos/farmacología , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Triazoles/farmacología , Acrilatos/química , Antiinflamatorios no Esteroideos/síntesis química , Antiinflamatorios no Esteroideos/química , Antineoplásicos/síntesis química , Antineoplásicos/química , Membrana Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Eritrocitos/efectos de los fármacos , Humanos , Simulación del Acoplamiento Molecular , Estructura Molecular , Ovalbúmina/metabolismo , Desnaturalización Proteica/efectos de los fármacos , Albúmina Sérica Bovina/metabolismo , Relación Estructura-Actividad , Triazoles/química , Células Tumorales Cultivadas
9.
Bioorg Chem ; 89: 102986, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31146198

RESUMEN

In continuance with earlier reported work, an extension has been carried out by the same research group. Mulling over the ongoing condition of resistance to existing antimalarial agents, we had reported synthesis and antimalarial activity of certain pyrazole-1,3,4-oxadiazole hybrid compounds. Bearing previous results in mind, our research group ideated to design and synthesize some more derivatives with varied substitutions of acetophenone and hydrazide. Following this, derivatives 5a-r were synthesized and tested for antimalarial efficacy by schizont maturation inhibition assay. Further, depending on the literature support and results of our previous series, certain potent compounds (5f, 5n and 5r) were subjected to Falcipain-2 inhibitory assay. Results obtained for these particular compounds further strengthened our hypothesis. Here, in this series, compound 5f having unsubstituted acetophenone part and a furan moiety linked to oxadiazole ring emerged as the most potent compound and results were found to be comparable to that of the most potent compound (indole bearing) of previous series. Additionally, depending on the available literature, compounds (5a-r) were tested for their antileishmanial potential. Compounds 5a, 5c and 5r demonstrated dose-dependent killing of the promastigotes. Their IC50 values were found to be 33.3 ±â€¯1.68, 40.1 ±â€¯1.0 and 19.0 ±â€¯1.47 µg/mL respectively. These compounds (5a, 5c and 5r) also had effects on amastigote infectivity with IC50 of 44.2 ±â€¯2.72, 66.8 ±â€¯2.05 and 73.1 ±â€¯1.69 µg/mL respectively. Further target validation was done using molecular docking studies. Acute oral toxicity studies for most active compounds were also performed.


Asunto(s)
Antimaláricos/farmacología , Antiprotozoarios/farmacología , Leishmania/efectos de los fármacos , Oxadiazoles/química , Plasmodium falciparum/efectos de los fármacos , Animales , Antimaláricos/química , Antimaláricos/metabolismo , Antiprotozoarios/síntesis química , Antiprotozoarios/química , Sitios de Unión , Supervivencia Celular/efectos de los fármacos , Cisteína Endopeptidasas/química , Cisteína Endopeptidasas/metabolismo , Diseño de Fármacos , Concentración 50 Inhibidora , Leishmania/fisiología , Macrófagos/citología , Macrófagos/metabolismo , Macrófagos/parasitología , Ratones , Simulación del Acoplamiento Molecular , Oxadiazoles/síntesis química , Oxadiazoles/farmacología , Estructura Terciaria de Proteína , Pirazoles/química , Células RAW 264.7 , Ratas , Ratas Wistar , Relación Estructura-Actividad
10.
IUBMB Life ; 70(8): 732-742, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29935010

RESUMEN

The complex life cycle of intracellular parasitic protozoans entails multiple rounds of DNA replication and mitosis followed by cytokinesis to release daughter parasites. To gain insights into mitotic events it is imperative to identify the biomarkers that constitute the chromosome segregation machinery in the parasite. Chromosomal loci called centromeres and their associated proteins play an essential role in accurate chromosome segregation. Although new information on the centromere-kinetochore proteins has been added to the existing pool of knowledge, a paucity of biomarkers for nuclear division prevents a global view of chromosome segregation mechanism in the malaria parasite. In Plasmodium falciparum, except CENH3 and CENP-C homologues, other centromere associated proteins responsible for centromere functions and kinetochore assembly are not known. The focus of this review is to summarize the current understanding on the centromere organization and its associated proteins in eukaryotes with the emerging information in P. falciparum. © 2018 IUBMB Life, 70(8):732-742, 2018.


Asunto(s)
Centrómero/genética , Proteínas Cromosómicas no Histona/genética , Malaria Falciparum/genética , Plasmodium falciparum/genética , Autoantígenos/genética , Cromatina/genética , Segregación Cromosómica/genética , Cinetocoros/química , Malaria Falciparum/parasitología , Mitosis/genética , Plasmodium falciparum/patogenicidad
11.
Bioorg Chem ; 77: 106-124, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29353728

RESUMEN

Depravity of malaria in terms of morbidity and mortality in human beings makes it a major health issue in tropical and subtropical areas of the globe. Drug counterfeiting and non-adherence to the treatment regimen have significantly contributed to development and spread of multidrug resistance that has highlighted the need for development of novel and more efficient antimalarial drugs. Complexity associated with cancer disease and prevalence of diversified cell populations vindicates highly specific treatment options for treatment of cancer. Resistance to these anticancer agents has posed a great hindrance in successful treatment of cancer. Pondering this ongoing situation, it was speculated to develop novel compounds targeting malaria and cancer. Moving on the same aisle, we synthesized pyrazole acrylic acid based oxadiazole and amide derivatives using multi-step reaction pathways (6a-x; 6a'-h'). Schizont maturation inhibition assay was employed to determine antimalarial potential. Compound 6v emerged as the most potent antimalarial agent targeting falcipain-2 enzyme. Anticancer activity was done using sulforhodamine B assay. Compounds 6b' and 6g' demonstrated promising results against all the tested cell lines. Further, Microscopic view clearly indicated formation of apoptotic bodies, chromatin condensation, shrinkage of cells and bleb formation. Validation of the results was achieved using molecular docking studies. From the obtained results, it was observed that cyclization (oxadiazole) favored antimalarial activity while non-cyclized compounds (amides) emerged as better anticancer agents.


Asunto(s)
Acrilatos/farmacología , Amidas/farmacología , Antimaláricos/farmacología , Antineoplásicos/farmacología , Oxadiazoles/farmacología , Pirazoles/farmacología , Acrilatos/química , Amidas/síntesis química , Amidas/química , Antimaláricos/síntesis química , Antimaláricos/química , Antineoplásicos/síntesis química , Antineoplásicos/química , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Simulación del Acoplamiento Molecular , Estructura Molecular , Oxadiazoles/síntesis química , Oxadiazoles/química , Pruebas de Sensibilidad Parasitaria , Plasmodium falciparum/efectos de los fármacos , Pirazoles/química , Relación Estructura-Actividad
12.
Toxicol Mech Methods ; 28(1): 45-54, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28715929

RESUMEN

Glucocorticoids are known to have vital effects on metabolism, behavior and immunity. Any sort of impairment in their synthesis may lead to the generation of numerous ill health effects. Different environmental toxicants, including bisphenols and their analogs pose deleterious effect on the biosynthesis of glucocorticoids, thereby leading to endocrine disruption. In order to assess the effect of these environmental toxicants on gluocorticoid biosynthetic pathway, an in silico study was performed. This involved molecular docking studies of 18 ligands with the selected participating enzymes of the pathway. These enzymes were CYP11A1, CYP11B2, CYP19A1, CYP17A1, 3α/20ß-HSD, 3ß/17ß-HSD and CYP21A2. Comparison of their binding affinity was made with the known inhibitors of these enzymes. In case of CYP11A1, Bisphenol M (BP M) had the lowest docking score (D score) of -8.699 kCal/mol, and was better than that of the standard, Metyrapone. Bisphenol PH (BP PH) was found to have significant affinity with CYP11B2. In case CYP19A1, results were found to be comparable with the standards, Exemestane and Letrozole. BP PH elicited better results than the standard Abiraterone acetate against CYP17A1. BP M had a D score of -7.759 against 3α/20ß-HSD, again better results than the standard, Trilostane. Upon molecular docking of BP PH against CYP21A2, it was seen that amongst all the analogs, it had maximum interactions along with the lowest D score. From all the above instances mentioned, it is quite evident that certain BPA analogs have more potential to modulate the enzymes involved in comparison to the known inhibitors.


Asunto(s)
Compuestos de Bencidrilo/toxicidad , Inhibidores Enzimáticos del Citocromo P-450/toxicidad , Sistema Enzimático del Citocromo P-450/metabolismo , Disruptores Endocrinos/toxicidad , Contaminantes Ambientales/toxicidad , Glucocorticoides/biosíntesis , Hidroxiesteroide Deshidrogenasas/antagonistas & inhibidores , Simulación del Acoplamiento Molecular , Fenoles/toxicidad , Compuestos de Bencidrilo/química , Compuestos de Bencidrilo/metabolismo , Sitios de Unión , Inhibidores Enzimáticos del Citocromo P-450/química , Inhibidores Enzimáticos del Citocromo P-450/metabolismo , Sistema Enzimático del Citocromo P-450/química , Disruptores Endocrinos/química , Disruptores Endocrinos/metabolismo , Contaminantes Ambientales/química , Contaminantes Ambientales/metabolismo , Hidroxiesteroide Deshidrogenasas/química , Hidroxiesteroide Deshidrogenasas/metabolismo , Ligandos , Fenoles/química , Fenoles/metabolismo , Unión Proteica , Conformación Proteica , Medición de Riesgo , Relación Estructura-Actividad
13.
J Mol Recognit ; 30(12)2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28639323

RESUMEN

Dioxins and dioxin-like compounds (DLCs) are known to cause endocrine disruption in humans and animals. Being lipophilic xenobiotic chemicals, they can be easily absorbed into the biological system from the surrounding environments, thereby causing various health dysfunctions. In the present study, a total of 100 dioxins and DLCs were taken, and their binding pattern was assessed with the xenosensors pregnane X receptor (PXR) and constitutive androstane receptor (CAR) in comparison with the corresponding known inhibitors and a well-studied endocrine disrupting xenobiotic, bisphenol A (BPA). The nuclear receptors CAR and PXR are known to play a significant role in handling potential toxins by coordinating cellular transport and metabolic functions of the same. Among different endocrine-disrupting chemicals used in the present study, DLCs (PCDFs and PCBs) elicited better interactions in comparison with the parent dioxin (polychlorinated dibenzodioxins) compounds. On comparing D scores of all the compounds against both the receptors, PCDF 8-hydroxy-3,4-dichlorodibenzofuran (8-OH-DCDF) and PCB tetrachlorobenzyltoluene (TCBT) exhibited significant molecular interactions against PXR (-7.633 kcal mol-1 ) and CAR (-8.389 kcal mol-1 ), respectively. Predominant interactions were found to be H-bonding, π-π stacking, hydrophobic, polar, and van der Waals. By contrast, BPA and some natural ligands tested in this study showed lower binding affinities with these receptors than certain DLCs reported herein, ie, certain DLCs might be more toxic than the proven toxic agent, BPA. Such studies play a pivotal role in the risk assessment of exposure to dioxins and DLCs on human health.


Asunto(s)
Simulación por Computador , Dioxinas y Compuestos Similares a la Dioxina/química , Dioxinas y Compuestos Similares a la Dioxina/metabolismo , Receptores Citoplasmáticos y Nucleares/química , Receptores Citoplasmáticos y Nucleares/metabolismo , Receptores de Esteroides/metabolismo , Medición de Riesgo , Biocatálisis , Receptor de Androstano Constitutivo , Interacciones Hidrofóbicas e Hidrofílicas , Ligandos , Simulación del Acoplamiento Molecular , Receptor X de Pregnano , Receptores de Esteroides/química , Reproducibilidad de los Resultados
14.
Toxicol Mech Methods ; 27(2): 151-163, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27997270

RESUMEN

Dioxins and dioxin-like compounds (DLCs) are the ones with poor water solubility and low volatility, resistant to physical, chemical and biological processes, persistent in the environment even under extreme conditions. Due to lipophilic nature, they get adhered to the fatty material and concentrate through biomagnification and bioaccumulation, thereby easily getting incorporated into food chains, paving the way to endocrine disruption via modulation of various human receptors. This in turn leads to certain adverse health effects. In the present study, a total of 100 dioxins and DLCs were taken and their binding pattern was assessed with the ketosteroid receptors, i.e. androgen (hAR), glucocorticoid (hGR), progesterone (hPR) and mineralocorticoid (hMR) in comparison to the corresponding natural steroids and a known endocrine disrupting xenobiotic, Bisphenol A (BPA). Most of the DLCs, particularly those bearing hydroxyl (-OH) group showed considerable affinities with ketosteroid receptors. On comparing D scores of all the dioxins and DLCs against all four receptors, compound 8-hydroxy-3,4-dichlorodibenzofuran(8-OH-DCDF) exhibited least D score of -9.549 kcal mol-1 against hAR. 3,8-Dihydroxy-2-chlorodibenzofuran(3,8-DiOH-CDF), 4'-hydroxy-2,3,4,5-tetrachlorobiphenyl (4'-OH-TCB) and 4-hydroxy-2,2',5'-trichlorobiphenyl(4-OH-TCB) also showed comparable molecular interactions with the ketosteroid receptors. These interactions mainly include H-bonding, π-π stacking, hydrophobic, polar and van der Waals' interactions. In contrast, BPA and some natural ligands tested in this study showed lower binding affinities with these receptors than certain DLCs reported herein, i.e. certain DLCs might be more toxic than the proven toxic agent, BPA. Such studies play a pivotal role in the risk assessment of exposure to dioxins and DLCs on human health.


Asunto(s)
Dioxinas/química , Disruptores Endocrinos/química , Cetosteroides/química , Receptores de Esteroides/química , Enlace de Hidrógeno , Interacciones Hidrofóbicas e Hidrofílicas , Ligandos , Simulación del Acoplamiento Molecular , Unión Proteica , Reproducibilidad de los Resultados , Medición de Riesgo
15.
Indian J Med Res ; 141(1): 81-9, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25857499

RESUMEN

BACKGROUND & OBJECTIVES: There is a worldwide emergence of fluoroquinolone resistance in Shigella species. To understand the molecular mechanisms associated with fluoroquinolone resistance, naturally occurring fluoroquinolone-resistant strains and laboratory-induced spontaneous mutants of Shigella spp. were used and the relative contributions of acrAB-tolC efflux pumps, gyrase and topoisomerase target gene mutations towards fluoroquinolone resistance were determined. METHODS: Eight Shigella flexneri and six S. dysenteriae clinical isolates were studied. Three consecutive mutants resistant to ciprofloxacin for S. flexneri SFM1 (≥ 0.25 µg/ml), SFM2 (≥ 4 µg/ml) and SFM3 (≥ 32 µg/ml) were selected in 15 steps from susceptible isolates by serial exposure to increasing concentrations of nalidixic acid and ciprofloxacin. Similarly, two mutants for S. dysenteriae SDM1 (≥ 0.25 µg/ml) and SDM2 (≥ 4 µg/ml) were selected in eight steps. After PCR amplification sequence analyses of gyrase and topoisomerase target genes were performed. Expression of efflux genes acrA, acrB, acrR and tolC was measured using real-time PCR. RESULTS: Mutations were observed in gyrA Ser [83]→Leu, Asp [87]→Asn/Gly, Val [196]→Ala and in parC Phe [93]→Val, Ser [80]→Ile, Asp [101]→Glu and Asp [110]→Glu. Overall, acrA and acrB overexpression was associated with fluoroquinolone resistance ( p0 <0.05); while tolC and acrR expression levels did not. INTERPRETATION & CONCLUSIONS: Fluoroquinolone resistance in Shigella spp. is the end product of either a single or a combination of mutations in QRDRs and/ or efflux activity. Novel polymorphisms were observed at Val [196]→Ala in gyrA in clinical isolates and Phe [93]→Val, Asp [101]→Glu, Asp [110]→Glu and in parC in majority of laboratory-grown mutants.


Asunto(s)
Antibacterianos/farmacología , Ciprofloxacina/farmacología , Farmacorresistencia Bacteriana/genética , Proteínas de Transporte de Membrana/genética , Mutación , Shigella/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Shigella/genética
16.
J Enzyme Inhib Med Chem ; 30(4): 597-606, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25333767

RESUMEN

One of the most viable options to tackle the growing resistance to the antimalarial drugs is hybrid molecules. It involves combination of different scaffolds in one frame that may lead to compounds with diverse biological profiles. In this context, new hybrids of three different scaffolds viz pyrazole, pyrazoline and thiosemicarbazone moiety were incorporated into one single compound and evaluated for their in vitro schizontocidal activity against the CQ-sensitive 3D7 strain of Plasmodium falciparum. Compounds with significant in vitro antimalarial activity were further evaluated for cytotoxicity against VERO cell lines. The best active compound 48 exhibited an IC50 of 1.13 µM. The in vitro results were further validated by quantitative structure-activity relationship (QSAR).


Asunto(s)
Antimaláricos/farmacología , Pirazoles/farmacología , Tioamidas/química , Animales , Antimaláricos/síntesis química , Antimaláricos/química , Plasmodium falciparum/efectos de los fármacos , Pirazoles/química , Relación Estructura-Actividad Cuantitativa
17.
Malar J ; 13: 475, 2014 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-25476240

RESUMEN

BACKGROUND: The conserved centromere-associated proteins, CENH3 (or CENP-A) and CENP-C are indispensable for the functional centromere-kinetochore assembly, chromosome segregation, cell cycle progression, and viability. The presence and functions of centromere proteins in Plasmodium falciparum are not well studied. Identification of PfCENP-C, an inner kinetochore protein (the homologue of human CENP-C) and its co-localization with PfCENH3 was recently reported. This study aims to decipher the functions of inner kinetochore protein, PfCENP-C as a centromere protein in P. falciparum. METHODS: Bio-informatic tools were employed to demarcate the two conserved domains of PfCENP-C, and the functions of PfCENP-C domains were demonstrated by functional complementation assays in the temperature sensitive (TS) mutant strains (mif2-3 and mif2-2) of Saccharomyces cerevisiae with MIF2p (the yeast homologue of CENP-C) loss-of-function. By site-directed mutagenesis, the key residues essential for PfCENP-C functions were determined. The chromatin immunoprecipitation was carried out to determine the in vivo binding of PfCENP-C to the Plasmodium centromeres and the in vivo interactions of PfCENP-C with PfCENH3, and mitotic spindles were shown by co-immunopreciptation experiments. RESULTS: The studies demonstrate that the motif and the dimerization domain of PfCENP-C is able to functionally complement MIF2p functions. The essential role of some of the key residues: F1993, F1996 and Y2069 within the PfCENP-C dimerization domain in mediating its functions and maintenance of mitotic spindle integrity is evident from this study. The pull-down assays show the association of PfCENP-C with PfCENH3 and mitotic spindles. The ChIP-PCR experiments confirm PfCENP-C-enriched Plasmodium centromeres. These studies thus provide an insight into the roles of this inner kinetochore protein and establish that the centromere proteins are evolutionary conserved in the parasite. CONCLUSIONS: PfCENP-C is a true CENP-C homologue in P. falciparum which binds to the centromeric DNA and its dimerization domain is essential for its in vivo functions as a centromere protein. The identification and functional characterization of the P. falciparum centromeric proteins will provide mechanistic insights into some of the mitotic events that occur during the chromosome segregation in human malaria parasite, P. falciparum.


Asunto(s)
Proteínas Cromosómicas no Histona/metabolismo , Plasmodium falciparum/fisiología , Multimerización de Proteína , Centrómero/metabolismo , Inmunoprecipitación de Cromatina , Proteínas Cromosómicas no Histona/genética , Biología Computacional , Análisis Mutacional de ADN , Prueba de Complementación Genética , Plasmodium falciparum/genética , Unión Proteica , Mapeo de Interacción de Proteínas , Estructura Terciaria de Proteína , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/fisiología
18.
Eur J Pharmacol ; 970: 176484, 2024 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-38467235

RESUMEN

Protein kinases play pivotal roles in various biological functions, influencing cell differentiation, promoting survival, and regulating the cell cycle. The disruption of protein kinase activity is intricately linked to pathways in tumor development. This manuscript explores the transformative impact of protein kinase inhibitors on cancer therapy, particularly their efficacy in cases driven by targeted mutations. Focusing on key tyrosine kinase inhibitors (TKIs) like Bcr-Abl, Epidermal Growth Factor Receptor (EGFR), and Vascular Endothelial Growth Factor Receptor (VEGFR), it targets critical kinase families in cancer progression. Clinical trial details of these TKIs offer insights into their therapeutic potentials. Learning from FDA-approved kinase inhibitors, the review dissects trends in kinase drug development since imatinib's paradigm-shifting approval in 2001. TKIs have evolved into pivotal drugs, extending beyond oncology. Ongoing clinical trials explore novel kinase targets, revealing the vast potential within the human kinome. The manuscript provides a detailed analysis of advancements until 2022, discussing the roles of specific oncogenic protein kinases in cancer development and carcinogenesis. Our exploration on PubMed for relevant and significant TKIs undergoing pre-FDA approval phase III clinical trials enriches the discussion with valuable findings. While kinase inhibitors exhibit lower toxicity than traditional chemotherapy in cancer treatment, challenges like resistance and side effects emphasize the necessity of understanding resistance mechanisms, prompting the development of novel inhibitors like osimertinib targeting specific mutant proteins. The review advocates thorough research on effective combination therapies, highlighting the future development of more selective RTKIs to optimize patient-specific cancer treatment and reduce adverse events.


Asunto(s)
Neoplasias Pulmonares , Neoplasias , Humanos , Factor A de Crecimiento Endotelial Vascular , Neoplasias/tratamiento farmacológico , Neoplasias/inducido químicamente , Inhibidores de Proteínas Quinasas/efectos adversos , Proteínas Quinasas/metabolismo , Mutación , Neoplasias Pulmonares/tratamiento farmacológico
19.
J Biomol Struct Dyn ; 41(17): 8121-8164, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36218071

RESUMEN

The spread of antimalarial drug resistance is a substantial challenge in achieving global malaria elimination. Consequently, the identification of novel therapeutic candidates is a global health priority. Malaria parasite necessitates hemoglobin degradation for its survival, which is mediated by Falcipain 2 (FP2), a promising antimalarial target. In particular, FP2 is a key enzyme in the erythrocytic stage of the parasite's life cycle. Here, we report the screening of approved drugs listed in DrugBank using a computational pipeline that includes drug-likeness, toxicity assessments, oral toxicity evaluation, oral bioavailability, docking analysis, maximum common substructure (MCS) and molecular dynamics (MD) Simulations analysis to identify capable FP2 inhibitors, which are hence potential antiplasmodial agents. A total of 45 drugs were identified, which have positive drug-likeness, no toxic features and good bioavailability. Among these, six drugs showed good binding affinity towards FP2 compared to E64, an epoxide known to inhibit FP2. Notably, two of them, Cefalotin and Cefoxitin, shared the highest MCS with E64, which suggests that they possess similar biological activity as E64. In an investigation using MD for 100 ns, Cefalotin and Cefoxitin showed adequate protein compactness as well as satisfactory complex stability. Overall, these computational approach findings can be applied for designing and developing specific inhibitors or new antimalarial agents for the treatment of malaria infections.Communicated by Ramaswamy H. Sarma.

20.
Res Sq ; 2023 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-37790487

RESUMEN

Background: Postnatal care, crucial for preventing and assessing complications after birth, remains low in India. An interactive mHealth community-based postnatal intervention was implemented to promote healthy maternal behaviors through knowledge and social support in rural Northern India. However, there is limited information on how virtual health interventions in resource-constrained settings are perceived by the users and which elements influence their engagement and sustained participation. Objective: We explored the user perceptions of acceptability and impact of a virtual interactive maternal and child health intervention pilot tested in Punjab State, India, including their perspectives on barriers and facilitators to engage with this intervention. Methods: This qualitative study was embedded within extensive mixed-method research, and oriented by the Realist Evaluation approach. Sixteen participants were recruited from the parent study. They were identified by purposive sampling to cover diverse levels of attendance and engagement with the intervention. In-depth interviews were conducted by phone. Following translation, a framework analysis was completed to search for the main themes. Feedback was requested from intervention moderators during the process to prioritize local interpretation. Results: Study participants reported overall satisfaction with the intervention. The mothers appreciated the educational material provided and the communication with other participants and health professionals. Across context, intervention, and actor domains, the barriers most commented on were network and connectivity challenges, lack of time due to household responsibilities, and feeling uncomfortable sharing personal experiences. Family buy-in and support were fundamental for overcoming the high domestic workload and baby care. Another facilitator mentioned was moderators' guidance on using the different intervention modalities. Regarding perceived impact, participants shared that MeSSSSage increased their capability and motivation to breastfeed, seek care as needed, and use contraception according to their preferences. Finally, participants suggested adding more topics to the educational content and adjusting the dynamics within the group calls to improve the intervention. Conclusions: This study identifies the high acceptability and perceived impact of a novel postnatal care program in a rural setting, including the users' perceived barriers to engaging with the intervention and possible solutions to overcome them. These findings enable refinement of the ongoing intervention, providing a more robust framing for its scalability and long-term sustainability. On a larger scale, conclusions from this research provide new insights and encouragement to global stakeholders who aspire to improve maternal and neonatal outcomes in low-income and middle-income countries through mHealth.

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