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1.
Can J Neurol Sci ; : 1-8, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38525880

RESUMO

OBJECTIVE: We aimed to evaluate the effect of yoga on motor and non-motor symptoms and cortical excitability in patients with Parkinson's disease (PD). METHODS: We prospectively evaluated 17 patients with PD at baseline, after one month of conventional care, and after one month of supervised yoga sessions. The motor and non-motor symptoms were evaluated using the Unified Parkinson's disease Rating Scale (motor part III), Hoehn and Yahr stage, Montreal Cognitive Assessment, Hamilton depression rating scale, Hamilton anxiety rating scale, non-motor symptoms questionnaire and World Health Organization quality of life questionnaire. Transcranial magnetic stimulation was used to record resting motor threshold, central motor conduction time, ipsilateral silent period (iSP), contralateral silent period (cSP), short interval intracortical inhibition (SICI), and intracortical facilitation. RESULTS: The mean age of the patients was 55.5 ± 10.8 years, with a mean duration of illness of 4.0 ± 2.5 years. The postural stability of the patients significantly improved following yoga (0.59 ± 0.5 to 0.18 ± 0.4, p = 0.039). There was a significant reduction in the cSP from baseline (138.07 ± 27.5 ms) to 4 weeks of yoga therapy (116.94 ± 18.2 ms, p = 0.004). In addition, a significant reduction in SICI was observed after four weeks of yoga therapy (0.22 ± 0.10) to (0.46 ± 0.23), p = 0.004). CONCLUSION: Yoga intervention can significantly improve postural stability in patients with PD. A significant reduction of cSP and SICI suggests a reduction in GABAergic neurotransmission following yoga therapy that may underlie the improvement observed in postural stability. CLINICALTRIALSGOV IDENTIFIER: CTRI/2019/02/017564.

2.
3 Biotech ; 14(2): 59, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38314316

RESUMO

Polyhydroxybutyrate (PHB) is known for wide applications, biocompatibility, and degradability; however, it cannot be commercialized due to conventional recovery using solvents. The present study employed mechanical cell-disruption methods, such as Pestle and mortar, sonication, and glass bead vortexing, for solvent-free extraction of PHA from Bacillus sp. Different time intervals were set for grinding (5, 10, 15 min), sonicating (1, 3 and 5 min), and vortexing (2, 5 and 8 g glass beads with 5, 10 and 15 min each) hence studying their effect on cell lysis to release PHA. Tris buffer containing phenylmethyl sulfonyl fluoride (PMSF) (20 mM Tris-HCl, pH 8.0, 1 mM PMSF) was employed as a lysis buffer to study its action over Bacillus cells. Its presence was checked with the above methods in cell lysis. Sonicating cells for 5 min in the presence of lysis buffer achieved a maximum PHA yield of 45%. Cell lysis using lysis buffer yielded 35% PHA when vortexing with 5 g glass beads for 15 min. Grinding cells for 15 min showed a maximum yield of 34% but lacked a lysis buffer. The overall results indicated that the action of lysis buffer and physical extraction methods improved PHA yield by %. Therefore, the study sought to evaluate the feasibility of applying laboratory methods for cell disruption. These methods can showcase possible opportunities in large-scale applications. The polymer yield results were compared with standard sodium hypochlorite extraction. Confirmation of obtained polymers as polyhydroxy butyrate (PHB) was made through FTIR and 1HNMR characterization.

3.
Sci Rep ; 14(1): 2182, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38272929

RESUMO

The Monsoon Intra-Seasonal Oscillations in the Bay of Bengal (MISO-BOB) field campaign was conducted in the Indian Ocean during the 2018 and 2019 summer monsoon seasons. WC-130J aircraft of the 53rd Weather Reconnaissance Squadron of the US Air Force participated in the campaign in June 2018. The dropsonde observations across a tropical supercluster showed zonal wind variations in association with the structure of the convectively coupled Kelvin wave (CCKW). Within the supercluster, easterlies (westerlies) were observed in the upper (lower) troposphere; this transformation occurred just below the 0[Formula: see text] C level. The cold pool had an easterly component throughout, and it was coldest (by 2.5[Formula: see text] C) at the center of the supercluster, deepest ([Formula: see text] [Formula: see text]) at its rear/western end, and shallowest ([Formula: see text] 300 m) at the front/eastern end. The level of free convection (LFC) at the front end was at [Formula: see text] altitude. At the eastern flank of the supercluster, zonal convergence in the lower troposphere occurred between 500-1500 m levels above the surface between the westerlies within the supercluster and opposing ambient easterlies. Thus, the uplifting of conditionally unstable air parcels above LFC to the east of the supercluster was likely to occur due to this convergence rather than the cold pool influence. Conversely, the western flank of the supercluster had low-level zonal divergence. These observations support the notion of 'self-similarity' among the mesoscale convective systems and large-scale waves.

4.
Ophthalmic Genet ; 45(2): 207-209, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37722826

RESUMO

BACKGROUND: We present a case of a child with Floating-Harbor Syndrome (FHS) with bilateral chorioretinal coloboma (CC). To the best of our knowledge, this is the first case report of this association. Floating- Harbor syndrome is an extremely rare autosomal dominant genetic disorder with approximately 100 cases reported. It is characterized by a series of atypical features that include short stature with delayed bone age, low birth weight, skeletal anomalies, delayed speech development, and dysmorphic facial characteristics that typically portray a triangular face, deep-set eyes, long eyelashes, and prominent nose. MATERIALS AND METHODS: Our patient was examined by a pediatric ophthalmologist for the time at age of 7. Visual acuity, optical coherence tomography (OCT) and Optos imaging were collected on every visit. The patient had whole genome sequencing ordered by a pediatric geneticist to confirm Floating-Harbor syndrome. RESULTS: We present the patient's OCT and Optos images that illustrate the location of the patient's inferior chorioretinal coloboma in both eyes. The whole genome sequencing report collected revealed a heterozygous de novo pathogenic variant in the SRCAP gene, consistent with a Floating-Harbor syndrome diagnosis in the literature. DISCUSSION: Both genetic and systemic findings are consistent with the diagnosis of Floating-Harbor syndrome in our patient. Rubenstein-Taybi and Floating-Harbor syndrome share a similarity in molecular and physical manifestations, but because of the prevalence in Rubenstein-Taybi diagnoses, it is a syndromic condition that includes coloboma and frequently associated with each other. Therefore, a retinal exam should become part of the standard protocol for those with FHS, as proper diagnosis, examination and treatment can prevent irreversible retinal damage.


Assuntos
Anormalidades Múltiplas , Coloboma , Anormalidades Craniofaciais , Comunicação Interventricular , Humanos , Criança , Coloboma/diagnóstico , Coloboma/genética , Anormalidades Múltiplas/genética , Anormalidades Múltiplas/diagnóstico , Anormalidades Craniofaciais/diagnóstico , Anormalidades Craniofaciais/genética , Transtornos do Crescimento/diagnóstico , Transtornos do Crescimento/genética
5.
Multimed Tools Appl ; 81(5): 7253-7270, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35095330

RESUMO

In recent years, there has been an enormous demand for the security of image multimedia in healthcare organizations. Many schemes have been developed for the security preservation of data in e-health systems however the schemes are not adaptive and cannot resist chosen and known-plaintext attacks. In this contribution, we present an adaptive framework aimed at preserving the security and confidentiality of images transmitted through an e-healthcare system. Our scheme utilizes the 3D-chaotic system to generate a keystream which is used to perform 8-bit and 2-bit permutations of the image. We perform pixel diffusion by a key-image generated using the Piecewise Linear Chaotic Map (PWLCM). We calculate an image parameter using the pixels of the image and perform criss-cross diffusion to enhance security. We evaluate the scheme's performance in terms of histogram analysis, information entropy analysis, statistical analysis, and differential analysis. Using the scheme, we obtain the average Number of Pixels Change Rate (NPCR) and Unified Average Changing Intensity (UACI) values for an image of size 256 × 256 equal to 99.5996 and 33.499 respectively. Furthermore, the average entropy is 7.9971 and the average Peak Signal to Noise Ratio (PSNR) is 7.4756. We further test the scheme on 50 chest X-Ray images of patients having COVID-19 and viral pneumonia and found the average values of variance, PSNR, entropy, and Structural Similarity Index (SSIM) to be 257.6268, 7.7389, 7.9971, and 0.0089 respectively. Furthermore, the scheme generates completely uniform histograms for medical images which reveals that the scheme can resist statistical attacks and can be applied as a security framework in AI-based healthcare.

6.
Indian J Dent Res ; 33(4): 462-464, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-37006016

RESUMO

Introduction: A modified frenal treatment for aberrant frenum is presented in this report to reduce scar tissue formation and maintain the attached gingiva. Description: The case report describes two cases in which a V-shaped incision removed the aberrant frenum and then the flaps of the frenum were sutured at the mid line. Results: The results showed reduced scar tissue in the mid line and the tissue healed with adequate attached gingiva. Take-Away Lessons: The modified frenotomy technique presented here is ideal for a large frenum that could expose the underlying connective tissue that could reduce the scar tissue formation.


Assuntos
Diastema , Freio Labial , Humanos , Freio Labial/cirurgia , Freio Labial/patologia , Cicatriz/complicações , Cicatriz/patologia , Gengiva , Tecido Conjuntivo , Retalhos Cirúrgicos/cirurgia
7.
Genes Genet Syst ; 96(4): 187-191, 2021 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-34803080

RESUMO

Colorectal cancer (CRC), which includes the development of cancer from the colon or rectum, is one of the highly prevalent cancers in the populations of Jammu and Kashmir (J&K) in India. However, case-control genetic association studies on CRC are lacking in this population. Various genome-wide association studies have previously shown that single-nucleotide polymorphisms (SNPs) of the AT-rich interaction domain 5B (ARID5B) gene located on chromosome 10q21.2 contribute substantially to the development of colorectal cancer. The association between ARID5B and CRC risk in north Indian population groups is still unknown. To understand the role of ARID5B SNPs in CRC in the population of J&K, we designed a case-control study to investigate the association of the cancer susceptibility variant rs10740055 of ARID5B with CRC in the population of J&K. The study included 180 cases and 390 healthy controls. Genotyping of the rs10740055 variant was performed by RT-PCR using the TaqMan assay technique. Hardy-Weinberg equilibrium of the variant was assessed using the chi-squared test. The allele- and genotype-specific risks were estimated by odds ratios (ORs) with 95% confidence intervals (CIs). The rs10740055 variant showed a higher risk for colorectal cancer with an OR of 3.35 (1.99-5.65 at 95% CI) and P = 0.000005 corrected for age, gender, ethnicity, BMI, alcohol intake and smoking. Our results indicate that the A allele of rs10740055 imparts risk to the population and also that a larger sample size is needed for further statistical validation. The association of other variants in other ARID family genes should also be tested as their role cannot be ruled out.


Assuntos
Neoplasias Colorretais , Estudo de Associação Genômica Ampla , Estudos de Casos e Controles , Neoplasias Colorretais/genética , Proteínas de Ligação a DNA/genética , Predisposição Genética para Doença , Genótipo , Humanos , Índia , Polimorfismo de Nucleotídeo Único , Fatores de Transcrição/genética
8.
Front Microbiol ; 12: 751225, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34659185

RESUMO

Dietary fiber and flavonoids have substantial influence on the human gut microbiota composition that significantly impact health. Recent studies with dietary supplements such as quercetin and rice bran have shown beneficial impacts on the host alongside a positive influence of the gut microbiota. The specific bacterial species impacted by quercetin or rice bran in the diet is not well understood. In this study, we used a minibioreactor array system as a model to determine the effect of quercetin and rice bran individually, as well as in combination, on gut microbiota without the confounding host factors. We found that rice bran exerts higher shift in gut microbiome composition when compared to quercetin. At the species level, Acidaminococcus intestini was the only significantly enriched taxa when quercetin was supplemented, while 15 species were enriched in rice bran supplementation and 13 were enriched when quercetin and rice bran were supplemented in combination. When comparing the short chain fatty acid production, quercetin supplementation increased isobutyrate production while propionate dominated the quercetin and rice bran combined group. Higher levels of propionate were highly correlated to the lower abundance of the potentially pathogenic Enterobacteriaceae family. These findings suggest that the combination of quercetin and rice bran serve to enrich beneficial bacteria and reduce potential opportunistic pathogens. In vivo studies are necessary to determine how this synergy of quercetin and rice bran on microbiota impact host health.

9.
Int J Mol Sci ; 22(13)2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34208885

RESUMO

We previously demonstrated that flavonoid metabolites inhibit cancer cell proliferation through both CDK-dependent and -independent mechanisms. The existing evidence suggests that gut microbiota is capable of flavonoid biotransformation to generate bioactive metabolites including 2,4,6-trihydroxybenzoic acid (2,4,6-THBA), 3,4-dihydroxybenzoic acid (3,4-DHBA), 3,4,5-trihyroxybenzoic acid (3,4,5-THBA) and 3,4-dihydroxyphenylacetic acid (DOPAC). In this study, we screened 94 human gut bacterial species for their ability to biotransform flavonoid quercetin into different metabolites. We demonstrated that five of these species were able to degrade quercetin including Bacillus glycinifermentans, Flavonifractor plautii, Bacteroides eggerthii, Olsenella scatoligenes and Eubacterium eligens. Additional studies showed that B. glycinifermentans could generate 2,4,6-THBA and 3,4-DHBA from quercetin while F. plautii generates DOPAC. In addition to the differences in the metabolites produced, we also observed that the kinetics of quercetin degradation was different between B. glycinifermentans and F. plautii, suggesting that the pathways of degradation are likely different between these strains. Similar to the antiproliferative effects of 2,4,6-THBA and 3,4-DHBA demonstrated previously, DOPAC also inhibited colony formation ex vivo in the HCT-116 colon cancer cell line. Consistent with this, the bacterial culture supernatant of F. plautii also inhibited colony formation in this cell line. Thus, as F. plautii and B. glycinifermentans generate metabolites possessing antiproliferative activity, we suggest that these strains have the potential to be developed into probiotics to improve human gut health.


Assuntos
Ácido 3,4-Di-Hidroxifenilacético/farmacologia , Antineoplásicos/farmacologia , Bactérias/classificação , Bromobenzoatos/farmacologia , Ácido Gálico/farmacologia , Hidroxibenzoatos/farmacologia , Quercetina/química , Ácido 3,4-Di-Hidroxifenilacético/química , Actinobacteria/genética , Actinobacteria/isolamento & purificação , Actinobacteria/metabolismo , Antineoplásicos/química , Bacillus/genética , Bacillus/isolamento & purificação , Bacillus/metabolismo , Bactérias/genética , Bactérias/isolamento & purificação , Bactérias/metabolismo , Proteínas de Bactérias , Bacteroides/genética , Bacteroides/isolamento & purificação , Bacteroides/metabolismo , Bromobenzoatos/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Clostridiales/genética , Clostridiales/isolamento & purificação , Clostridiales/metabolismo , Eubacterium/genética , Eubacterium/isolamento & purificação , Eubacterium/metabolismo , Ácido Gálico/química , Microbioma Gastrointestinal , Perfilação da Expressão Gênica , Regulação Bacteriana da Expressão Gênica , Células HCT116 , Humanos , Hidroxibenzoatos/química , Filogenia , Análise de Sequência de RNA
10.
Sci Rep ; 11(1): 3355, 2021 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-33558617

RESUMO

Storms are convective cells responsible for the major fraction of convective precipitation. Here, the pre-monsoon and monsoon season characteristics of storms are reported at Lucknow, Patna, Bhopal, and Nagpur in India using equivalent radar reflectivity factor ([Formula: see text]) given at these radar locations. It is observed that the lifetime, speed of propagation, area, volume, echo top height and thickness lie in ranges 0.3-3 h, 5-60 km [Formula: see text], 4-184 [Formula: see text], 8-1600 [Formula: see text], 2-14 km, and 0.5-16 km respectively. For both seasons, the relationships between radar estimated rain volume (RERV; range [Formula: see text]-[Formula: see text] [Formula: see text]) and area-time integral (ATI; range 1-100 [Formula: see text] h) are established which are considered as a representative of total precipitation resulted from an individual storm during its life cycle. The results from statistical analysis of RERV-ATI pairs suggest that storms at Lucknow have similar seasonal characteristics at 87% confidence interval while other locations exhibit dissimilarities. In addition, the vertical profiles of radar reflectivity (VPRRs) of storms are constructed at their life phases, namely cumulus, mature and dissipation. It is concluded that the vertical [Formula: see text] gradient in mixed-phase region (5-8 km) is lower (2-2.9 dBZ [Formula: see text]) at cumulus and dissipation phases than at mature phase (3.6-4.4 dBZ [Formula: see text]) in monsoon season. For pre-monsoon season, this gradient lies between 3.3-5.2 dBZ [Formula: see text] at mature phase. Our results are of great importance for advancing knowledge about storm-scale, which has implications in short-range weather forecasting as well as developing new convective parametrization schemes.

11.
IEEE Internet Things J ; 8(21): 15652-15662, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-35582243

RESUMO

Internet of Medical Things (IoMT)-driven smart health and emotional care is revolutionizing the healthcare industry by embracing several technologies related to multimodal physiological data collection, communication, intelligent automation, and efficient manufacturing. The authentication and secure exchange of electronic health records (EHRs), comprising of patient data collected using wearable sensors and laboratory investigations, is of paramount importance. In this article, we present a novel high payload and reversible EHR embedding framework to secure the patient information successfully and authenticate the received content. The proposed approach is based on novel left data mapping (LDM), pixel repetition method (PRM), RC4 encryption, and checksum computation. The input image of size [Formula: see text] is upscaled by using PRM that guarantees reversibility with lesser computational complexity. The binary secret data are encrypted using the RC4 encryption algorithm and then the encrypted data are grouped into 3-bit chunks and converted into decimal equivalents. Before embedding, these decimal digits are encoded by LDM. To embed the shifted data, the cover image is divided into [Formula: see text] blocks and then in each block, two digits are embedded into the counter diagonal pixels. For tamper detection and localization, a checksum digit computed from the block is embedded into one of the main diagonal pixels. A fragile logo is embedded into the cover images in addition to EHR to facilitate early tamper detection. The average peak signal to noise ratio (PSNR) of the stego-images obtained is 41.95 dB for a very high embedding capacity of 2.25 bits per pixel. Furthermore, the embedding time is less than 0.2 s. Experimental results reveal that our approach outperforms many state-of-the-art techniques in terms of payload, imperceptibility, computational complexity, and capability to detect and localize tamper. All the attributes affirm that the proposed scheme is a potential candidate for providing better security and authentication solutions for IoMT-based smart health.

12.
Cryo Letters ; 42(5): 251-260, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35363845

RESUMO

The reduction in population genetic diversity due to inbreeding depression and the negative impact of human activity on habitats ultimately generates an extinction debt. Therefore, there is always a dire need to save wild population and to protect biodiversity. Preservation of wildlife female germplasm, i.e., oocytes and embryos, is a promising biotechnological tool to conserve species' biodiversity. Other applied tools of Assisted Reproductive Technology (ART) which assure conservation of endangered species include artificial insemination (AI), embryo transfer technology (ETT), and sperm cryopreservation. Only a few studies show the possibility of adapting the cryopreservation techniques developed for domestic animal female genetic material for use with wild animals. Difficulty is encountered in getting samples, accesses to animals for study, and the standardization of protocols for cryopreservation of such genetic material. Our meta-analysis of the literature (published or in press) and on-going studies found that biobanking for the preservation of vital tissues of wild animals is possible. Somatic tissue sections, ovarian tissues, sperms, oocytes and embryos are potential materials for preservation by vitrification. As vitrification is economical and easily applied, it appears to the best option currently available for the preservation of wildlife female genetics in order to conserve species' biodiversity.


Assuntos
Bancos de Espécimes Biológicos , Criopreservação , Animais , Criopreservação/métodos , Criopreservação/veterinária , Transferência Embrionária , Espécies em Perigo de Extinção , Feminino , Oócitos
13.
Int J Mol Sci ; 21(23)2020 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-33260951

RESUMO

Aspirin, synthesized and marketed in 1897 by Bayer, is one of the most widely used drugs in the world. It has a well-recognized role in decreasing inflammation, pain and fever, and in the prevention of thrombotic cardiovascular diseases. Its anti-inflammatory and cardio-protective actions have been well studied and occur through inhibition of cyclooxygenases (COX). Interestingly, a vast amount of epidemiological, preclinical and clinical studies have revealed aspirin as a promising chemopreventive agent, particularly against colorectal cancers (CRC); however, the primary mechanism by which it decreases the occurrences of CRC has still not been established. Numerous mechanisms have been proposed for aspirin's chemopreventive properties among which the inhibition of COX enzymes has been widely discussed. Despite the wide attention COX-inhibition has received as the most probable mechanism of cancer prevention by aspirin, it is clear that aspirin targets many other proteins and pathways, suggesting that these extra-COX targets may also be equally important in preventing CRC. In this review, we discuss the COX-dependent and -independent pathways described in literature for aspirin's anti-cancer effects and highlight the strengths and limitations of the proposed mechanisms. Additionally, we emphasize the potential role of the metabolites of aspirin and salicylic acid (generated in the gut through microbial biotransformation) in contributing to aspirin's chemopreventive actions. We suggest that the preferential chemopreventive effect of aspirin against CRC may be related to direct exposure of aspirin/salicylic acid or its metabolites to the colorectal tissues. Future investigations should shed light on the role of aspirin, its metabolites and the role of the gut microbiota in cancer prevention against CRC.


Assuntos
Aspirina/uso terapêutico , Neoplasias Colorretais/enzimologia , Neoplasias Colorretais/prevenção & controle , Prostaglandina-Endoperóxido Sintases/metabolismo , Animais , Aspirina/farmacologia , Quimioprevenção , Neoplasias Colorretais/tratamento farmacológico , Inibidores de Ciclo-Oxigenase/farmacologia , Inibidores de Ciclo-Oxigenase/uso terapêutico , Microbioma Gastrointestinal/efeitos dos fármacos , Humanos
14.
Medicina (Kaunas) ; 56(11)2020 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-33114101

RESUMO

About 40-70% of drug molecules in the clinical development pipeline suffer from one of either low aqueous solubility, poor absorption, or extremely low bioavailability. Approximately 75% of the world population relies on traditional therapies and therefore there has been a growing interest in the utilization of natural compounds. Zerumbone is one such natural compound, classified as a sesquiterpenoid that is extracted from the essential volatile oils of rhizomes from Zingiber zerumbet. It possesses strong antitumor, antioxidant, antimicrobial, and anti-inflammatory activity. However, despite promising preclinical studies demonstrating the therapeutic utility of zerumbone, its clinical development has been limited due to its low aqueous solubility, poor absorption, or associated low bioavailability. Multiple reviews demonstrating the pharmacological effects of zerumbone for various diseases have been published. However, to our knowledge, no review demonstrates the various formulation strategies developed to overcome the biopharmaceutical challenges of zerumbone. The purpose of this review is to provide a comprehensive perspective on zerumbone as a molecule for formulation development. A section related to pharmacokinetics, toxicity, and patents of zerumbone is included. This review provides the importance of developing novel formulations of zerumbone to overcome its biopharmaceutical challenges thereby advance its potential in the treatment of various diseases.


Assuntos
Sesquiterpenos , Disponibilidade Biológica , Humanos , Nanotecnologia , Solubilidade
15.
Molecules ; 25(9)2020 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-32397626

RESUMO

Despite decades of research to elucidate the cancer preventive mechanisms of aspirin and flavonoids, a consensus has not been reached on their specific modes of action. This inability to accurately pinpoint the mechanism involved is due to the failure to differentiate the primary targets from its associated downstream responses. This review is written in the context of the recent findings on the potential pathways involved in the prevention of colorectal cancers (CRC) by aspirin and flavonoids. Recent reports have demonstrated that the aspirin metabolites 2,3-dihydroxybenzoic acid (2,3-DHBA), 2,5-dihydroxybenzoic acid (2,5-DHBA) and the flavonoid metabolites 2,4,6-trihydroxybenzoic acid (2,4,6-THBA), 3,4-dihydroxybenzoic acid (3,4-DHBA) and 3,4,5-trihydroxybenzoic acid (3,4,5-THBA) were effective in inhibiting cancer cell growth in vitro. Limited in vivo studies also provide evidence that some of these hydroxybenzoic acids (HBAs) inhibit tumor growth in animal models. This raises the possibility that a common pathway involving HBAs may be responsible for the observed cancer preventive actions of aspirin and flavonoids. Since substantial amounts of aspirin and flavonoids are left unabsorbed in the intestinal lumen upon oral consumption, they may be subjected to degradation by the host and bacterial enzymes, generating simpler phenolic acids contributing to the prevention of CRC. Interestingly, these HBAs are also abundantly present in fruits and vegetables. Therefore, we suggest that the HBAs produced through microbial degradation of aspirin and flavonoids or those consumed through the diet may be common mediators of CRC prevention.


Assuntos
Aspirina/farmacologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Neoplasias Colorretais/prevenção & controle , Flavonoides/farmacologia , Frutas/metabolismo , Hidroxibenzoatos/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Animais , Aspirina/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Neoplasias Colorretais/tratamento farmacológico , Flavonoides/metabolismo , Frutas/química , Ácido Gálico/metabolismo , Gentisatos/metabolismo , Humanos , Hidroxibenzoatos/metabolismo , Sistema de Sinalização das MAP Quinases/genética
16.
Mol Divers ; 24(4): 1265-1279, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31506871

RESUMO

Diphenyl ether derivatives inhibit mycobacterial cell wall synthesis by inhibiting an enzyme, enoyl-acyl carrier protein reductase (InhA), which catalyses the last step in the fatty acid synthesis cycle of genus Mycobacterium. To select and validate a protein crystal structure of enoyl-acyl carrier protein reductase of Mycobacterium tuberculosis for designing inhibitors using molecular modelling, a cross-docking and correlation study was performed. A series of novel 1-(3-(3-hydroxy-4-phenoxyphenyl)-5-phenyl-4,5-dihydro-1H-pyrazol-1-yl) ethan-1-ones were synthesized from this model and screened for their antitubercular activity against M. tuberculosis H37Rv. Compound PYN-8 showed good antitubercular activity on M. tuberculosis H37Rv (MIC = 4-7 µM) and Mycobacterium bovis (% inhibition at 10 µM = 95.91%). Cytotoxicity of all the synthesized derivatives was assessed using various cell lines, and they were found to be safe. Structure of PYN-8 was also confirmed by single-crystal X-ray diffraction. The molecular modelling studies also corroborated the biological activity of the compounds. Further, in silico findings revealed that all these tested compounds exhibited good ADME properties and drug likeness and thus may be considered as potential candidates for further drug development.


Assuntos
Antituberculosos/síntese química , Antituberculosos/farmacologia , Éteres Fenílicos/síntese química , Éteres Fenílicos/farmacologia , Tuberculose/tratamento farmacológico , Proteínas de Bactérias/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Simulação por Computador , Cristalografia por Raios X , Desenho de Fármacos , Células HEK293 , Células HeLa , Humanos , Células MCF-7 , Testes de Sensibilidade Microbiana/métodos , Simulação de Acoplamento Molecular , Mycobacterium tuberculosis/efeitos dos fármacos , Células PC-3 , Relação Estrutura-Atividade , Tuberculose/metabolismo
17.
Drug Dev Res ; 81(3): 315-328, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31782209

RESUMO

A new series of novel triclosan (2,4,4'-trichloro-2'-hydroxydiphenylether) analogues were designed, synthesized, and screened for their in vitro antimycobacterial and antibacterial activities. Most of the compounds showed significant activity against Mycobacterium tuberculosis H37Rv strain with minimum inhibitory concentration (MIC) values in 20-40 µM range in GAST/Fe medium when compared with triclosan (43 µM) in the first week of assay, and after additional incubation, seven compounds, that is, 2a, 2c, 2g, 2h, 2i, 2j, and 2m, exhibited MIC values at the concentration of 20-40 µM. The compounds also showed more significant activity against Bacillus subtilis and Staphylococcus aureus. The synthesized compounds showed druggable properties, and the predicted ADME (absorption, distribution, metabolism, and excretion) properties were within the acceptable limits. The in silico studies predicted better interactions of compounds with target protein residues and a higher dock score in comparison with triclosan. Molecular dynamics simulation study of the most active compound 2i was performed in order to further explore the stability of the protein-ligand complex and the protein-ligand interaction in detail.


Assuntos
Antituberculosos/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Triclosan/farmacologia , Aminas/síntese química , Aminas/química , Aminas/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Antituberculosos/síntese química , Antituberculosos/química , Bacillus subtilis/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Staphylococcus aureus/efeitos dos fármacos , Relação Estrutura-Atividade , Triclosan/análogos & derivados , Triclosan/química
18.
Mol Med Rep ; 21(1): 20-34, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31746356

RESUMO

Although compelling evidence exists on the ability of aspirin to treat colorectal cancer (CRC), and numerous theories and targets have been proposed, a consensus has not been reached regarding its mechanism of action. In this regard, a relatively unexplored area is the role played by aspirin metabolites 2,3­dihydroxybenzoic acid (2,3­DHBA) and 2,5­dihydroxybenzoic acid (2,5­DHBA) in its chemopreventive actions. In a previous study, we demonstrated that 2,3­DHBA and 2,5­DHBA inhibited CDK1 enzyme activity in vitro. The aim of the present study was to understand the effect of these metabolites on the enzyme activity of all CDKs involved in cell cycle regulation (CDKs 1, 2, 4 and 6) as well as their effect on clonal formation in three different cancer cell lines. Additionally, in silico studies were performed to determine the potential sites of interactions of 2,3­DHBA and 2,5­DHBA with CDKs. We demonstrated that 2,3­DHBA and 2,5­DHBA inhibits CDK­1 enzyme activity beginning at 500 µM, while CDK2 and CDK4 activity was inhibited only at higher concentrations (>750 µM). 2,3­DHBA inhibited CDK6 enzyme activity from 250 µM, while 2,5­DHBA inhibited its activity >750 µM. Colony formation assays showed that 2,5­DHBA was highly effective in inhibiting clonal formation in HCT­116 and HT­29 CRC cell lines (250­500 µM), and in the MDA­MB­231 breast cancer cell line (~100 µM). In contrast 2,3­DHBA was effective only in MDA­MB­231 cells (~500 µM). Both aspirin and salicylic acid failed to inhibit all four CDKs and colony formation. Based on the present results, it is suggested that 2,3­DHBA and 2,5­DHBA may contribute to the chemopreventive properties of aspirin, possibly through the inhibition of CDKs. The present data and the proposed mechanisms should open new areas for future investigations.


Assuntos
Aspirina , Ciclo Celular/efeitos dos fármacos , Neoplasias Colorretais , Quinases Ciclina-Dependentes/antagonistas & inibidores , Proteínas de Neoplasias/antagonistas & inibidores , Aspirina/farmacocinética , Aspirina/farmacologia , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/enzimologia , Neoplasias Colorretais/patologia , Quinases Ciclina-Dependentes/metabolismo , Células HCT116 , Células HT29 , Humanos , Proteínas de Neoplasias/metabolismo
19.
BMC Med Inform Decis Mak ; 19(1): 139, 2019 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-31331394

RESUMO

BACKGROUND: Despite WHO guidelines for testing all suspected cases of malaria before initiating treatment, presumptive malaria treatment remains common practice among some clinicians and in certain low-resource settings the capacity for microscopic testing is limited. This can lead to misdiagnosis, resulting in increased morbidity due to lack of treatment for undetected conditions, increased healthcare costs, and potential for drug resistance. This is particularly an issue as multiple conditions share the similar etiologies to malaria, including brucellosis, a rare, under-detected zoonosis. Linking rapid diagnostic tests (RDTs) and digital test readers for the detection of febrile illnesses can mitigate this risk and improve case management of febrile illness. METHODS: This technical advance study examines Connected Diagnostics, an approach that combines the use of point-of-care RDTs for malaria and brucellosis, digitally interpreted by a rapid diagnostic test reader (Deki Reader) and connected to mobile payment mechanisms to facilitate the diagnosis and treatment of febrile illness in nomadic populations in Samburu County, Kenya. Consenting febrile patients were tested with RDTs and patient diagnosis and risk information were uploaded to a cloud database via the Deki Reader. Patients with positive diagnoses were provided digital vouchers for transportation to the clinic and treatment via their health wallet on their mobile phones. RESULTS: In total, 288 patients were tested during outreach visits, with 9% testing positive for brucellosis and 0.6% testing positive for malaria. All patients, regardless of diagnosis were provided with a mobile health wallet on their cellular phones to facilitate their transport to the clinic, and for patients testing positive for brucellosis or malaria, the wallet funded their treatment. The use of the Deki Reader in addition to quality diagnostics at point of care also facilitated geographic mapping of patient diagnoses in relation to key risk areas for brucellosis transmission. CONCLUSIONS: This study demonstrates that the Connected Dx approach can be effective even when addressing a remote, nomadic population and a rare disease, indicating that this approach to diagnosing, treatment, and payment for healthcare costs is feasible and can be scaled to address more prevalent diseases and conditions in more populous contexts.


Assuntos
Brucelose/diagnóstico , Malária/diagnóstico , Telemedicina , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Brucelose/epidemiologia , Brucelose/terapia , Telefone Celular , Criança , Pré-Escolar , Testes Diagnósticos de Rotina/métodos , Estudos de Viabilidade , Feminino , Geografia Médica , Humanos , Lactente , Quênia/epidemiologia , Malária/epidemiologia , Masculino , Pessoa de Meia-Idade , Testes Imediatos , Migrantes , Adulto Jovem
20.
Sci Rep ; 9(1): 10321, 2019 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-31311996

RESUMO

Significant increase in the frequency of occurrences of rainfall extremes has been reported over several parts of the world. These extreme events were defined at individual grids without considering their spatial extent. Here, using ground-based observations over India during boreal summer, we show that the average size of spatially collocated rainfall extremes has been significantly increasing since 1980. However, the frequency of occurrences of such collocated extreme events remains unchanged. Around 90% of the total number of large-sized events (area ≥ 70 × 103 km2) of our study period (1951 to 2015) have occurred after 1980. Some of the major floods in recent decades over India are attributed to these large events. These events have distinctive precursory planetary-scale conditions, unlike their smaller counterparts. As the underlying physical mechanisms of extremes rainfall events are size-dependent, their changing spatial extent needs to be considered to understand the observed trends correctly and obtain realistic future projections.

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