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1.
Proteins ; 92(4): 540-553, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38037760

RESUMO

Preliminary studies have shown BRCA1 (170-1600) residues to be intrinsically disordered with unknown structural details. However, thousands of clinically reported variants have been identified in this central region of BRCA1. Therefore, we aimed to characterize h-BRCA1(260-553) to assess the structural basis for pathogenicity of two rare missense variants Ser282Leu, Gln356Arg identified from the Indian and Russian populations respectively. Small-angle X-ray scattering analysis revealed WT scores Rg -32 Å, Dmax -93 Å, and Rflex-51% which are partially disordered, whereas Ser282Leu variant displayed a higher degree of disorderedness and Gln356Arg was observed to be aggregated. WT protein also possesses an inherent propensity to undergo a disorder-to-order transition in the presence of cruciform DNA and 2,2,2-Trifluoroethanol (TFE). An increased alpha-helical pattern was observed with increasing concentration of TFE for the Gln356Arg mutant whereas Ser282Leu mutant showed significant differences only at the highest TFE concentration. Furthermore, higher thermal shift was observed for WT-DNA complex compared to the Gln356Arg and Ser282Leu protein-DNA complex. Moreover, mature amyloid-like fibrils were observed with 30 µM thioflavin T (ThT) at 37°C for Ser282Leu and Gln356Arg proteins while the WT protein exists in a protofibril state as observed by TEM. Gln356Arg formed higher-order aggregates with amyloidogenesis over time as monitored by ThT fluorescence. In addition, computational analyses confirmed larger conformational fluctuations for Ser282Leu and Gln356Arg mutants than for the WT. The global structural alterations caused by these variants provide a mechanistic approach for further classification of the variants of uncertain clinical significance in BRCA1 into amyloidogenic variants which may have a significant role in disease pathogenesis.


Assuntos
Amiloide , Mutação de Sentido Incorreto , DNA
2.
Molecules ; 28(24)2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-38138636

RESUMO

Urinary tract infection is an infectious disease that requires immediate treatment. It can occur in any age group and involves both genders equally. The present study was to check the resistance of some antibiotics and to assess the antibacterial potential of three extracts of three plants against notorious bacteria involved in urinary tract infections. Along with assessing the antibacterial activity of plant extracts, we checked for the anticancer potential of these extracts against the cancer cell lines MCF-7 and A2780. Cancer is the leading cause of mortality in developed countries. Determinations of total flavonoid content, total phenolic content, total alkaloid content, total tannin content, total carotenoid content, and total steroid content were performed. The disk diffusion method was used to analyze the antibacterial activity of plant extracts. Ethanolic extract of Selenicereus undatus showed sensitivity (25-28 mm) against bacteria, whereas chloroform and hexane extracts showed resistance against all bacteria except Staphylococcus (25 mm). Ethanolic extract of Pistacia vera L. showed sensitivity (22-25 mm) against bacteria, whereas chloroform and hexane extracts showed resistance. Ethanolic extract of Olea europaea L. showed sensitivity (8-16 mm) against all bacteria except Staphylococcus, whereas chloroform and hexane extracts showed resistance. Positive controls showed variable zones of inhibition (2-60 mm), and negative control showed 0-1 mm. The antibiotic resistance was much more prominent in the case of hexane and chloroform extracts of all plants, whereas ethanolic extract showed a sensitivity of bacteria against extracts. Both cell lines, MCF-7 and A2780, displayed decreased live cells when treated with plant extracts.


Assuntos
Olea , Neoplasias Ovarianas , Pistacia , Masculino , Feminino , Humanos , Hexanos , Linhagem Celular Tumoral , Células MCF-7 , Clorofórmio , Antibacterianos/farmacologia , Extratos Vegetais/farmacologia , Staphylococcus , Bactérias , Testes de Sensibilidade Microbiana
3.
Sensors (Basel) ; 22(4)2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-35214251

RESUMO

In many smart devices and numerous digital applications, authentication mechanisms are widely used to validate the legitimacy of users' identification. As a result of the increased use of mobile devices, most people tend to save sensitive and secret information over such devices. Personal Identification Number (PIN)-based and alphanumeric passwords are simple to remember, but at the same time, they are vulnerable to hackers. Being difficult to guess and more user-friendly, graphical passwords have grown in popularity as an alternative to all such textual passwords. This paper describes an innovative, hybrid, and much more robust user authentication approach, named GRA-PIN (GRAphical and PIN-based), which combines the merits of both graphical and pin-based techniques. The feature of simple arithmetic operations (addition and subtraction) is incorporated in the proposed scheme, through which random passwords are generated for each login attempt. In the study, we have conducted a comparative study between the GRA-PIN scheme with existing PIN-based and pattern-based (swipe-based) authentications approaches using the standard Software Usability Scale (SUS). The usability score of GRA-PIN was analyzed to be as high as 94%, indicating that it is more reliable and user friendly. Furthermore, the security of the proposed scheme was challenged through an experiment wherein three different attackers, having a complete understanding of the proposed scheme, attempted to crack the technique via shoulder surfing, guessing, and camera attack, but they were unsuccessful.


Assuntos
Esportes , Telemedicina , Segurança Computacional , Computadores de Mão , Confidencialidade , Humanos , Ombro , Software
4.
Sensors (Basel) ; 22(23)2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36501799

RESUMO

The Internet of medical things (IoMT) provides an ecosystem in which to connect humans, devices, sensors, and systems and improve healthcare services through modern technologies. The IoMT has been around for quite some time, and many architectures/systems have been proposed to exploit its true potential. Healthcare through the Internet of things (IoT) is envisioned to be efficient, accessible, and secure in all possible ways. Even though the personalized health service through IoT is not limited to time or location, many associated challenges have emerged at an exponential pace. With the rapid shift toward IoT-enabled healthcare systems, there is an extensive need to examine possible threats and propose countermeasures. Authentication is one of the key processes in a system's security, where an individual, device, or another system is validated for its identity. This survey explores authentication techniques proposed for IoT-enabled healthcare systems. The exploration of the literature is categorized with respect to the technology deployment region, as in cloud, fog, and edge. A taxonomy of attacks, comprehensive analysis, and comparison of existing authentication techniques opens up possible future directions and paves the road ahead.


Assuntos
Ecossistema , Internet das Coisas , Humanos , Internet , Tecnologia , Atenção à Saúde
5.
Sci Rep ; 14(1): 8408, 2024 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-38600156

RESUMO

The current study was conducted on the inhabitants living in the area adjacent to the Hudiara drain using bore water and vegetables adjacent to the Hudiara drain. Toxic heavy metals badly affect human health because of industrial environmental contamination. Particularly hundreds of millions of individuals globally have faced the consequences of consuming water and food tainted with pollutants. Concentrations of heavy metals in human blood were elevated in Hudiara drainings in Lahore city, Pakistan, due to highly polluted industrial effluents. The study determined the health effects of high levels of heavy metals (Cd, Cu, Zn, Fe, Pb, Ni, Hg, Cr) on residents of the Hudiara draining area, including serum MDA, 8-Isoprostane, 8-hydroxyguanosine, and creatinine levels. An absorption spectrophotometer was used to determine heavy metals in wate water, drinking water, soil, plants and human beings blood sampleas and ELISA kits were used to assess the level of 8-hydroxyguanosine, MDA, 8-Isoprostane in plasma serum creatinine level. Waste water samples, irrigation water samples, drinking water samples, Soil samples, Plants samples and blood specimens of adult of different weights and ages were collected from the polluted area of the Hudiara drain (Laloo and Mohanwal), and control samples were obtained from the unpolluted site Sheiikhpura, 60 km away from the site. Toxic heavy metals in blood damage the cell membrane and DNA structures, increasing the 8-hydroxyguanosine, MDA, creatinine, and 8-Isoprostane. Toxic metals contaminated bore water and vegetables, resulting in increased levels of creatinine, MDA, Isoprostane, and 8-hydroxy-2-guanosine in the blood of inhabitants from the adjacent area Hudiara drain compared to the control group. In addition,. This study also investigated heavy metal concentrations in meat and milk samples from buffaloes, cows, and goats. In meat, cow samples showed the highest Cd, Cu, Fe and Mn concentrations. In milk also, cows exhibited elevated Cu and Fe levels compared to goats. The results highlight species-specific variations in heavy metal accumulation, emphasizing the need for targeted monitoring to address potential health risks. The significant difference between the two groups i.e., the control group and the affected group, in all traits of the respondents (weight, age, heavy metal values MDA, 8-Isoprostane, 8-hydroxyguaniosine, and serum creatinine level). Pearson's correlation coefficient was calculated. The study has shown that the level of serum MDA, 8-Isoprostane, 8-hydroxyguaniosine, or creatinine has not significantly correlated with age, so it is independent of age. This study has proved that in Pakistan, the selected area of Lahore in the villages of Laloo and Mohanwal, excess of heavy metals in the human body damages the DNA and increases the level of 8-Isoprostane, MDA, creatinine, and 8-hydroxyguaniosine. As a result, National and international cooperation must take major steps to control exposure to heavy metals.


Assuntos
Água Potável , Metais Pesados , Poluentes do Solo , Adulto , Humanos , Animais , Bovinos , Creatinina/análise , Poluentes do Solo/metabolismo , Paquistão , Água Potável/análise , Cádmio/análise , Monitoramento Ambiental/métodos , Metais Pesados/análise , Intoxicação por Metais Pesados , Solo/química , Verduras/metabolismo , Dano ao DNA , DNA , Cabras/metabolismo , Medição de Risco
6.
J Biomol Struct Dyn ; 41(19): 9879-9889, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-36404616

RESUMO

Breast cancer type 2 susceptibility (BRCA2) protein plays a crucial role in DNA double-strand breaks repair mechanism by homologous recombination. Pathogenic mutations in the BRCA2 gene confer an increased risk of hereditary breast and ovarian cancer (HBOC). Different missense mutations are identified from a larger cohort of patient populations in the BRCA2. However, most missense mutations are classified as 'Variants of Uncertain Significance' (VUS) due to a lack of data from structural, functional, and clinical assessments. Therefore, this study focused on assessing VUS identified in the α-helical domain of h-BRCA2 using different in silico tools and structure-based molecular dynamics simulation. A total of 286 identified VUS were evaluated using Align-GVGD, PROVEAN and PANTHER servers and 18 variants were predicted to be pathogenic. Further, out of 18 variants analyzed using the ConSurf server, 16 variants were found to be evolutionary conserved. These 16 conserved variants were submitted to PremPS and Dynamut server to assess the effect of the mutation at the protein structure level; 12 mutations were predicted to have a destabilizing effect on the native protein structure. Finally, molecular dynamics simulations revealed 5 variants BRCA2 Cys2646Tyr, Asp2665Val, Trp2619Arg, Trp2619Ser and Tyr2660Cys can alter the folding pattern and need further validation using in vitro, structural and in vivo studies to classify as pathogenic.Communicated by Ramaswamy H. Sarma.


Assuntos
Neoplasias da Mama , Neoplasias Ovarianas , Humanos , Feminino , Genes BRCA2 , Neoplasias da Mama/genética , Mutação , Mutação de Sentido Incorreto , Proteína BRCA1/genética , Predisposição Genética para Doença , Neoplasias Ovarianas/genética , Proteína BRCA2/genética
7.
ACS Omega ; 8(18): 16273-16283, 2023 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-37179615

RESUMO

Human-ribosomal s6 kinase 1 (h-RSK1) is an effector kinase of the Ras/MAPK signaling pathway, which is involved in the regulation of the cell cycle, proliferation, and survival. RSKs comprise two functionally distinct kinase domains at the N-terminal (NTKD) and C-terminal (CTKD) separated by a linker region. The mutations in RSK1 may have the potential to provide an extra benefit to the cancer cell to proliferate, migrate, and survive. The present study focuses on evaluating the structural basis for the missense mutations identified at the C-terminal kinase domain of human-RSK1. A total of 139 mutations reported on RSK1 were retrieved from cBioPortal, where 62 were located at the CTKD region. Furthermore, 10 missense mutations Arg434Pro, Thr701Met, Ala704Thr, Arg725Trp, Arg726Gln, His533Asn, Pro613Leu, Ser720Cys, Arg725Gln, and Ser732Phe were predicted to be deleterious using in silico tools. To our observation, these mutations are located in the evolutionarily conserved region of RSK1 and shown to alter the inter- and intramolecular interactions and also the conformational stability of RSK1-CTKD. The molecular dynamics (MD) simulation study further revealed that the five mutations Arg434Pro, Thr701Met, Ala704Thr, Arg725Trp, and Arg726Gln showed maximum structural alterations in RSK1-CTKD. Thus, based on the in silico and MD simulation analysis, it can be concluded that the reported mutations may serve as potential candidates for further functional studies.

8.
ACS Omega ; 7(42): 37654-37662, 2022 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-36312387

RESUMO

Bardet-Biedl Syndrome (BBS) is a rare inherited disorder resulting in multiple organ dysfunctions, whose cardinal clinical features include cognitive impairment, obesity, and renal dysfunction. Although it is highly heterogeneous at genetic levels, BBS10 is one of the major causative genes worldwide. The BBS10 protein is part of a multiprotein complex localized at the basal body of the primary cilium. With the advancement of sequencing technologies, novel missense mutations are regularly reported in BBS10. However, prioritizing missense variants and conducting further in-depth analysis are key challenges in addressing their pathogenic effect. This study aims to characterize the known missense mutations of BBS10 by combining nine different in silico tools (SIFT, SNAP2, PROVEAN, Align-GVGD, ConSurf, I Mutant, MuPro, PremPS, and Dynamut) and molecular dynamics (MD) simulations. A total of 101 BBS10 missense variants have been analyzed. Our results showed that six BBS10 missense variants (Ser191Leu, Cys19Gly, Ile342Thr, Cys371Ser, Ala417Glu, and Tyr613Cys) were potentially deleterious. Overall, this study provides a comprehensive workflow for screening BBS10 missense mutations to identify pathogenic variants effectively.

9.
Int J Biol Macromol ; 209(Pt A): 716-724, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35413318

RESUMO

Breast cancer type 2 susceptibility (BRCA2) protein plays an essential role in the repair mechanism of DNA double-strand breaks and interstrand cross-links by Homologous recombination. Germline mutations identified in the BRCA2 gene confer an increased risk of hereditary breast and ovarian cancer. Missense mutations are identified all over the gene, including the DNA binding region of BRCA2 that interacts with FANCD2. However, the majority of these missense mutations are classified as 'Variants of Uncertain Significance' due to a lack of structural, functional and clinical correlations. Therefore, multi-disciplinary in-silico, in-vitro and biophysical approaches have been explored to characterize an unclassified missense mutation, BRCA2 Arg2502Cys, identified from a case-control study. Circular-dichroism and Fluorescence spectroscopy show that the Arg2502Cys mutation in hBRCA2 (residues 2350-2545) decreases the α-helical/ß-sheet propensity of the wild-type protein and perturb the tertiary structure conformation. Molecular dynamics simulations revealed alteration in the intramolecular H-bonds, overall compactness and stability of the hydrophobic core were observed in the mutant protein. Principle component analysis indicated that Arg2502Cys mutant exhibited comparatively large conformational transitions and periodic fluctuation. Therefore, to our conclusion, BRCA2 Arg2502Cys mutant perturbed the structural integrity and conformational dynamics of BRCA2.


Assuntos
Neoplasias da Mama , Genes BRCA2 , Proteína BRCA2/genética , Estudos de Casos e Controles , DNA , Quebras de DNA de Cadeia Dupla , Feminino , Mutação em Linhagem Germinativa , Humanos , Mutação de Sentido Incorreto
10.
Int J Biol Macromol ; 104(Pt A): 1338-1344, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28684355

RESUMO

Fanconi anemia (FA), a cancer predisposition syndrome exhibits hallmark feature of radial chromosome formation, and hypersensitivity to DNA crosslinking agents. A set of FA pathway proteins mainly FANCI, FANCD2 and BRCA2 are expressed to repair the covalent crosslink between the dsDNA. However, FA, BRCA pathways play an important role in DNA ICL repair as well as in homologous recombination repair, but the presumptive role of FA-BRCA proteins has not clearly explored particularly in context to function associated protein-protein interactions (PPIs). Here, in-vivo, in-vitro and in-silico studies have been performed for functionally relevant domains of FANCI, FANCD2 and BRCA2. To our conclusion, FANCI ARM repeat interacts with FANCD2 CUE domain and BRCA2 C-terminal region. Interestingly, FANCD2 CUE domain also interacts strongly with BRCA2 C-terminal region. Interactions between BRCA2 CTR and functionally relevant mutations Ser222Ala (cell cycle checkpoint mutant) and Leu231Arg (DNA ICL repair mutant) present in FANCD2 CUE domain have been analysed. To our finding, these mutations abrogate the binding between FANCD2 CUE domain and BRCA2 CTR. Furthermore, (1) different domain of FANCI, FANCD2 and BRCA2 are playing important role in PPIs, (2) mutations cause the impairment in the PPIs which in turn may disrupt the DNA ICL repair mechanism.


Assuntos
Reparo do DNA , Proteínas de Grupos de Complementação da Anemia de Fanconi/metabolismo , Mapeamento de Interação de Proteínas , Proteínas de Grupos de Complementação da Anemia de Fanconi/química , Proteínas de Grupos de Complementação da Anemia de Fanconi/genética , Mutação , Domínios Proteicos , Sequências Repetitivas de Aminoácidos
11.
Parasitol Int ; 64(1): 43-9, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25280460

RESUMO

In the malarial parasite Plasmodium falciparum, the conserved ribosomal stalk protein P2 (PfP2) exhibits extra-ribosomal stage-specific oligomerization and trafficking to the host red cell membrane. Antibodies directed against PfP2 arrested cell division. We sought to examine whether P2 from a closely related Apicomplexan parasite, Toxoplasma gondii, exhibits similar properties in terms of its oligomeric status as well as such unique host-cell localization. Circular dichroism spectroscopy of recombinant P2 from T. gondii (TgP2) showed a structure similar to that of PfP2, but unlike PfP2, which forms SDS- and DTT-resistant oligomers, TgP2 exhibited only a weak SDS-resistant dimerization. Also, unlike PfP2 localization to the infected erythrocyte surface, TgP2 did not localize to the host membrane in T. gondii infected human foreskin fibroblast cells. However, P2 protein was detected on the free tachyzoite surface, corroborated by localization of epitope-tagged P2 transfected in T. gondii. The presence of P2 on the surface of P. falciparum merozoites was also observed, and specific antibodies raised against the P2 protein blocked both T. gondii and P. falciparum zoite invasion of the host cells. Thus, although certain moonlighting functions of the acidic ribosomal protein P2 are different amongst P. falciparum and T. gondii, the P2 protein localizes to the surface of the invasive zoite form, and appears to constitute a potential target for host cell invasion inhibition in both the Apicomplexan infections.


Assuntos
Anticorpos Antiprotozoários/imunologia , Fosfoproteínas/imunologia , Fosfoproteínas/metabolismo , Plasmodium falciparum/metabolismo , Proteínas Ribossômicas/imunologia , Proteínas Ribossômicas/metabolismo , Toxoplasma/metabolismo , Animais , Células Cultivadas , Clonagem Molecular , Eletroforese em Gel de Poliacrilamida , Humanos , Merozoítos , Microscopia de Fluorescência , Fosfoproteínas/química , Fosfoproteínas/genética , Plasmodium falciparum/imunologia , Plasmodium falciparum/patogenicidade , Multimerização Proteica , Proteínas de Protozoários/química , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Proteínas Ribossômicas/química , Proteínas Ribossômicas/genética , Toxoplasma/imunologia , Toxoplasma/patogenicidade
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