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1.
J Bacteriol ; 206(7): e0011924, 2024 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-38837341

RESUMO

RsgA (small ribosomal subunit, 30S, GTPase), a late-stage biogenesis factor, releases RbfA from 30S-RbfA complex. Escherichia coli ΔrsgA (deleted for rsgA) shows a slow growth phenotype and an increased accumulation of 17S rRNA (precursor of 16S rRNA) and the ribosomal subunits. Here, we show that the rescue of the ΔrsgA strain by multicopy infB (IF2) is enhanced by simultaneous overexpression of initiator tRNA (i-tRNA), suggesting a role of initiation complex formation in growth rescue. The synergistic effect of IF2/i-tRNA is accompanied by increased processing of 17S rRNA (to 16S), and protection of the 16S rRNA 3'-minor domain. Importantly, we show that an IF2-binding anticonvulsant drug, lamotrigine (Ltg), also rescues the ΔrsgA strain growth. The rescue is accompanied by increased processing of 17S rRNA, protection of the 3'-minor domain of 16S rRNA, and increased 70S ribosomes in polysome profiles. However, Ltg becomes inhibitory to the ΔrsgA strain whose growth was already rescued by an L83R mutation in rbfA. Interestingly, like wild-type infB, overproduction of LtgRinfB alleles (having indel mutations in their domain II) also rescues the ΔrsgA strain (independent of Ltg). Our observations suggest the dual role of IF2 in rescuing the ΔrsgA strain. First, together with i-tRNA, IF2 facilitates the final steps of processing of 17S rRNA. Second, a conformer of IF2 functionally compensates for RsgA, albeit poorly, during 30S biogenesis. IMPORTANCE: RsgA is a late-stage ribosome biogenesis factor. Earlier, infB (IF2) was isolated as a multicopy suppressor of the Escherichia coli ΔrsgA strain. How IF2 rescued the strain growth remained unclear. This study reveals that (i) the multicopy infB-mediated growth rescue of E. coli ΔrsgA and the processing of 17S precursor to 16S rRNA in the strain are enhanced upon simultaneous overexpression of initiator tRNA and (ii) a conformer of IF2, whose occurrence increases when IF2 is overproduced or when E. coli ΔrsgA is treated with Ltg (an anticonvulsant drug that binds to domain II of IF2), compensates for the function of RsgA. Thus, this study reveals yet another role of IF2 in ribosome biogenesis.


Assuntos
Proteínas de Escherichia coli , Escherichia coli , Lamotrigina , Ribossomos , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Escherichia coli/efeitos dos fármacos , Lamotrigina/farmacologia , Ribossomos/metabolismo , Fator de Iniciação 2 em Procariotos/metabolismo , Fator de Iniciação 2 em Procariotos/genética , RNA Ribossômico 16S/genética , Proteínas Ribossômicas/genética , Proteínas Ribossômicas/metabolismo , Regulação Bacteriana da Expressão Gênica , RNA de Transferência de Metionina/metabolismo , RNA de Transferência de Metionina/genética , Triazinas/farmacologia , Triazinas/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , GTP Fosfo-Hidrolases
2.
Mol Cancer ; 23(1): 50, 2024 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-38461268

RESUMO

Despite advancements in treatment protocols, cancer is one of the leading cause of deaths worldwide. Therefore, there is a need to identify newer and personalized therapeutic targets along with screening technologies to combat cancer. With the advent of pan-omics technologies, such as genomics, transcriptomics, proteomics, metabolomics, and lipidomics, the scientific community has witnessed an improved molecular and metabolomic understanding of various diseases, including cancer. In addition, three-dimensional (3-D) disease models have been efficiently utilized for understanding disease pathophysiology and as screening tools in drug discovery. An integrated approach utilizing pan-omics technologies and 3-D in vitro tumor models has led to improved understanding of the intricate network encompassing various signalling pathways and molecular cross-talk in solid tumors. In the present review, we underscore the current trends in omics technologies and highlight their role in understanding genotypic-phenotypic co-relation in cancer with respect to 3-D in vitro tumor models. We further discuss the challenges associated with omics technologies and provide our outlook on the future applications of these technologies in drug discovery and precision medicine for improved management of cancer.


Assuntos
Multiômica , Neoplasias , Humanos , Medicina de Precisão/métodos , Genômica/métodos , Neoplasias/tratamento farmacológico , Neoplasias/genética , Neoplasias/diagnóstico , Metabolômica/métodos , Descoberta de Drogas
3.
J Fluoresc ; 34(2): 915-923, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37418200

RESUMO

Fluorescence spectra of Pr3+ doped CdS nanoparticles, synthesized by chemical precipitation method, have been recorded at room temperature. The synthesized particles are nearly spherical shaped and the grain size is decreased with the increase in Pr3+ concentration. The chemical identity of the nanoparticles was confirmed by EDAX spectrum, the absorption peaks was confirmed by FTIR spectrum and then the recorded values were compared with the CIE diagram. The oscillator strengths of the 4f ↔ 4I transitions are parameterized in terms of three phenomenological Judd-Ofelt intensity parameters Ωλ (λ = 2, 4 and 6). Using the fluorescence data and these Ωλ parameters, theoretical and experimental study of various radiative properties viz., spontaneous emission probability (A), radiative life time , fluorescence branching ratio and stimulated emission cross-section were evaluated. The values of these parameters indicate that 3P0→ 3H4 transition can be considered to be good laser transition in the visible colour region. Also, excitation with 493 nm, leads to similar blue regions. The synthesized Pr3+ doped CdS nanomaterials could be useful for sensing and detecting devices, particularly for temperature sensing measurement and bio-sensing detection.

4.
Mol Biol Rep ; 51(1): 896, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39115550

RESUMO

CRISPR-based (Clustered regularly interspaced short palindromic repeats-based) technologies have revolutionized molecular biology and diagnostics, offering unprecedented precision and versatility. However, challenges remain, such as high costs, demanding technical expertise, and limited quantification capabilities. To overcome these limitations, innovative microfluidic platforms are emerging as powerful tools for enhancing CRISPR diagnostics. This review explores the exciting intersection of CRISPR and microfluidics, highlighting their potential to revolutionize healthcare diagnostics. By integrating CRISPR's specificity with microfluidics' miniaturization and automation, researchers are developing more sensitive and portable diagnostic tools for a range of diseases. These microfluidic devices streamline sample processing, improve diagnostic performance, and enable point-of-care applications, allowing for rapid and accurate detection of pathogens, genetic disorders, and other health conditions. The review discusses various CRISPR/Cas systems, including Cas9, Cas12, and Cas13, and their integration with microfluidic platforms. It also examines the advantages and limitations of these systems, highlighting their potential for detecting DNA and RNA biomarkers. The review also explores the key challenges in developing and implementing CRISPR-driven microfluidic diagnostics, such as ensuring robustness, minimizing cross-contamination, and achieving robust quantification. Finally, it highlights potential future directions for this rapidly evolving field, emphasizing the transformative potential of these technologies for personalized medicine and global health.


Assuntos
Sistemas CRISPR-Cas , Microfluídica , Sistemas CRISPR-Cas/genética , Humanos , Microfluídica/métodos , Patologia Molecular/métodos , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Técnicas de Diagnóstico Molecular/métodos , Edição de Genes/métodos , Dispositivos Lab-On-A-Chip
5.
Nucleic Acids Res ; 50(20): 11712-11726, 2022 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-36399509

RESUMO

Initiation factor 3 (IF3) regulates the fidelity of bacterial translation initiation by debarring the use of non-canonical start codons or non-initiator tRNAs and prevents premature docking of the 50S ribosomal subunit to the 30S pre-initiation complex (PIC). The C-terminal domain (CTD) of IF3 can carry out most of the known functions of IF3 and sustain Escherichia coli growth. However, the roles of the N-terminal domain (NTD) have remained unclear. We hypothesized that the interaction between NTD and initiator tRNAfMet (i-tRNA) is essential to coordinate the movement of the two domains during the initiation pathway to ensure fidelity of the process. Here, using atomistic molecular dynamics (MD) simulation, we show that R25A/Q33A/R66A mutations do not impact NTD structure but disrupt its interaction with i-tRNA. These NTD residues modulate the fidelity of translation initiation and are crucial for bacterial growth. Our observations also implicate the role of these interactions in the subunit dissociation activity of CTD of IF3. Overall, the study shows that the interactions between NTD of IF3 and i-tRNA are crucial for coupling the movements of NTD and CTD of IF3 during the initiation pathway and in imparting growth fitness to E. coli.


Assuntos
Proteínas de Escherichia coli , Escherichia coli , RNA de Transferência de Metionina , Cotovelo , Escherichia coli/metabolismo , Fatores de Iniciação de Peptídeos/metabolismo , Fator de Iniciação 3 em Procariotos/metabolismo , RNA de Transferência de Metionina/genética , RNA de Transferência de Metionina/metabolismo
6.
Eur J Public Health ; 34(2): 230-236, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38345619

RESUMO

BACKGROUND: Cognitive development in pre-schoolers through healthy eating and socio-demographic support is crucial for their later lives. We investigated healthy eating encouragement, socio-demographic factors and their association with cognitive development in pre-schoolers. METHODS: Quantitative data were collected using a multi-stage random sampling between February and April 2021. Pre-schoolers 36 and 71 months and their primary caregivers were recruited from three local government units of Rupandehi district. We compared healthy eating encouragement, socioeconomic and demographic factors with cognitive development using t-test, one-way analysis of variance and multiple linear regression analysis to identify the predictors of the cognitive development among pre-schoolers. RESULTS: Cognitive development in pre-schoolers is significantly positively associated with age 36-48 months (ß = 0.153; 95% CI: 0.12, 13.96), living in a nuclear family (ß = 0.121; 95% CI: 0.59, 6.88) and following Buddhism (ß = 0.148; 95% CI: 0.88, 14.32). Conversely, children from specific caste/ethnic backgrounds, such as Dalit (ß = -0.126; 95% CI: -10.79, -0.68), Janajati (ß = -0.237; 95% CI: -6.14, -2.09) and non-Dalit Tarai caste or ethnicity (ß = -0.133; 95% CI: -3.46, -0.25) and mothers employed (ß = -0.134; 95% CI: -10.62, -1.44) show significantly lower levels of cognitive development. CONCLUSIONS: The finding shows that socioeconomic factors have an influence on cognitive development and also stimulate the adoption of healthy eating encouragement practices.


Assuntos
Cognição , Dieta Saudável , Criança , Feminino , Humanos , Pré-Escolar , Nepal , Estudos Transversais , Demografia
7.
J Res Adolesc ; 34(2): 327-338, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38708916

RESUMO

The social identity development of adolescents in marginalized communities across the globe holds paramount significance in determining the overall well-being of its future population. Focusing on one such community, the Kodavas, an Indigenous community in South India, this study aims to understand the shifting configurations of social identity based on the changing sociocultural structure and its implications on identity perception among the adolescents belonging to the Kodava community in Kodagu district in Karnataka, India. This study used a qualitative research design to develop an analytical framework of social identity formation and its transitions in the context of the Kodavas. Data were collected from 188 adolescents (47% boys, 53% girls) between 13 and 17 years (M age = 15 years), in the form of essay writing. The findings based on thematic analysis highlight the core traditional elements of Kodava identity, factors influencing the transition in identity, and its reflection in the contemporary period.


Assuntos
Identificação Social , Humanos , Índia/etnologia , Adolescente , Masculino , Feminino , Pesquisa Qualitativa , Povos Indígenas/psicologia , Autoimagem
8.
J Indian Assoc Pediatr Surg ; 29(1): 75-77, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38405254

RESUMO

Hemangiomas are rare small bowel tumors requiring a high index of suspicion for diagnosis. We present a case of ileal hemangioma in a 3-year-old male presenting with recurrent anemia. The patient was diagnosed with a contrast-enhanced computed tomography abdomen and managed surgically by resection and anastomosis. Histopathologically, it was a solitary ileal cavernous hemangioma with a submucosal infiltrative pattern with serosa involvement and a normal mucosa.

9.
Nat Prod Rep ; 40(9): 1550-1582, 2023 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-37114973

RESUMO

Covering: up to fall 2022.Nonribosomal peptide synthetases (NRPSs) are a family of modular, multidomain enzymes that catalyze the biosynthesis of important peptide natural products, including antibiotics, siderophores, and molecules with other biological activity. The NRPS architecture involves an assembly line strategy that tethers amino acid building blocks and the growing peptides to integrated carrier protein domains that migrate between different catalytic domains for peptide bond formation and other chemical modifications. Examination of the structures of individual domains and larger multidomain proteins has identified conserved conformational states within a single module that are adopted by NRPS modules to carry out a coordinated biosynthetic strategy that is shared by diverse systems. In contrast, interactions between modules are much more dynamic and do not yet suggest conserved conformational states between modules. Here we describe the structures of NRPS protein domains and modules and discuss the implications for future natural product discovery.


Assuntos
Peptídeo Sintases , Peptídeos , Peptídeo Sintases/metabolismo , Domínio Catalítico , Domínios Proteicos
10.
Mol Microbiol ; 117(2): 462-479, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34889476

RESUMO

The anticodon stem of initiator tRNA (i-tRNA) possesses the characteristic three consecutive GC base pairs (G29:C41, G30:C40, and G31:C39 abbreviated as GC/GC/GC or 3GC pairs) crucial to commencing translation. To understand the importance of this highly conserved element, we isolated two fast-growing suppressors of Escherichia coli sustained solely on an unconventional i-tRNA (i-tRNAcg/GC/cg ) having cg/GC/cg sequence instead of the conventional GC/GC/GC. Both suppressors have the common mutation of V93A in initiation factor 3 (IF3), and additional mutations of either V32L (Sup-1) or H76L (Sup-2) in small subunit ribosomal protein 12 (uS12). The V93A mutation in IF3 was necessary for relaxed fidelity of i-tRNA selection to sustain on i-tRNAcg/GC/cg though with a retarded growth. Subsequent mutations in uS12 salvaged the retarded growth by enhancing the fidelity of translation. The H76L mutation in uS12 showed better fidelity of i-tRNA selection. However, the V32L mutation compensated for the deficient fidelity of i-tRNA selection by ensuring an efficient fidelity check by ribosome recycling factor (RRF). We reveal unique genetic networks between uS12, IF3 and i-tRNA in initiation and between uS12, elongation factor-G (EF-G), RRF, and Pth (peptidyl-tRNA hydrolase) which, taken together, govern the fidelity of translation in bacteria.


Assuntos
Escherichia coli , RNA de Transferência de Metionina , Escherichia coli/metabolismo , Iniciação Traducional da Cadeia Peptídica/genética , Fator de Iniciação 3 em Procariotos/metabolismo , Subunidades Proteicas , RNA de Transferência de Metionina/genética , RNA de Transferência de Metionina/metabolismo , Proteínas Ribossômicas/genética , Proteínas Ribossômicas/metabolismo
11.
Lancet ; 399(10333): 1391-1400, 2022 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-35381194

RESUMO

BACKGROUND: Dietary restriction of sodium has been suggested to prevent fluid overload and adverse outcomes for patients with heart failure. We designed the Study of Dietary Intervention under 100 mmol in Heart Failure (SODIUM-HF) to test whether or not a reduction in dietary sodium reduces the incidence of future clinical events. METHODS: SODIUM-HF is an international, open-label, randomised, controlled trial that enrolled patients at 26 sites in six countries (Australia, Canada, Chile, Colombia, Mexico, and New Zealand). Eligible patients were aged 18 years or older, with chronic heart failure (New York Heart Association [NYHA] functional class 2-3), and receiving optimally tolerated guideline-directed medical treatment. Patients were randomly assigned (1:1), using a standard number generator and varying block sizes of two, four, or six, stratified by site, to either usual care according to local guidelines or a low sodium diet of less than 100 mmol (ie, <1500 mg/day). The primary outcome was the composite of cardiovascular-related admission to hospital, cardiovascular-related emergency department visit, or all-cause death within 12 months in the intention-to-treat (ITT) population (ie, all randomly assigned patients). Safety was assessed in the ITT population. This study is registered with ClinicalTrials.gov, NCT02012179, and is closed to accrual. FINDINGS: Between March 24, 2014, and Dec 9, 2020, 806 patients were randomly assigned to a low sodium diet (n=397) or usual care (n=409). Median age was 67 years (IQR 58-74) and 268 (33%) were women and 538 (66%) were men. Between baseline and 12 months, the median sodium intake decreased from 2286 mg/day (IQR 1653-3005) to 1658 mg/day (1301-2189) in the low sodium group and from 2119 mg/day (1673-2804) to 2073 mg/day (1541-2900) in the usual care group. By 12 months, events comprising the primary outcome had occurred in 60 (15%) of 397 patients in the low sodium diet group and 70 (17%) of 409 in the usual care group (hazard ratio [HR] 0·89 [95% CI 0·63-1·26]; p=0·53). All-cause death occurred in 22 (6%) patients in the low sodium diet group and 17 (4%) in the usual care group (HR 1·38 [0·73-2·60]; p=0·32), cardiovascular-related hospitalisation occurred in 40 (10%) patients in the low sodium diet group and 51 (12%) patients in the usual care group (HR 0·82 [0·54-1·24]; p=0·36), and cardiovascular-related emergency department visits occurred in 17 (4%) patients in the low sodium diet group and 15 (4%) patients in the usual care group (HR 1·21 [0·60-2·41]; p=0·60). No safety events related to the study treatment were reported in either group. INTERPRETATION: In ambulatory patients with heart failure, a dietary intervention to reduce sodium intake did not reduce clinical events. FUNDING: Canadian Institutes of Health Research and the University Hospital Foundation, Edmonton, Alberta, Canada, and Health Research Council of New Zealand.


Assuntos
Insuficiência Cardíaca , Sódio na Dieta , Idoso , Canadá , Feminino , Insuficiência Cardíaca/tratamento farmacológico , Humanos , Masculino , Sódio , Resultado do Tratamento
12.
RNA Biol ; 20(1): 681-692, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-37676049

RESUMO

Lamotrigine (Ltg), an anticonvulsant drug, targets initiation factor 2 (IF2), compromises ribosome biogenesis and causes toxicity to Escherichia coli. However, our understanding of Ltg toxicity in E. coli remains unclear. While our in vitro assays reveal no effects of Ltg on the ribosome-dependent GTPase activity of IF2 or its role in initiation as measured by dipeptide formation in a fast kinetics assay, the in vivo experiments show that Ltg causes accumulation of the 17S precursor of 16S rRNA and leads to a decrease in polysome levels in E. coli. IF2 overexpression in E. coli increases Ltg toxicity. However, the overexpression of initiator tRNA (i-tRNA) protects it from the Ltg toxicity. The depletion of i-tRNA or overexpression of its 3GC mutant (lacking the characteristic 3GC base pairs in anticodon stem) enhances Ltg toxicity, and this enhancement in toxicity is synthetic with IF2 overexpression. The Ltg treatment itself causes a detectable increase in IF2 levels in E. coli and allows initiation with an elongator tRNA, suggesting compromise in the fidelity/specificity of IF2 function. Also, Ltg causes increased accumulation of ribosome-binding factor A (RbfA) on 30S ribosomal subunit. Based on our genetic and biochemical investigations, we show that Ltg compromises the function of i-tRNA/IF2 complex in ribosome maturation.


Assuntos
Anticonvulsivantes , Proteínas de Escherichia coli , Lamotrigina/farmacologia , Escherichia coli/genética , Fator de Iniciação 2 em Procariotos , RNA de Transferência de Metionina/genética , RNA Ribossômico 16S/genética , Ribossomos , Proteínas Ribossômicas , Proteínas de Escherichia coli/genética
13.
J Therm Biol ; 116: 103656, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37481935

RESUMO

In the present paper, the phenomena of heat transport inside human forearm tissue are studied through a one-dimensional nonlinear bioheat transfer model under the influence of various boundary and interface conditions. In this study, we considered temperature-dependent thermal conductivity and metabolic heat to predict temperature distribution inside the forearm tissue. We have studied the temperature distribution inside inner tissue and bone because it has been found that burn injuries are mostly affected by layer thickness. The temperature distribution inside human forearm tissue is analyzed using the finite difference and bvp4c numerical techniques. To examine the accuracy of present numerical code, we compare the obtained numerical result with the exact analytical result in a specific case and find an excellent agreement with the exact results. We also validated our present numerical code with a hybrid scheme based on Runge-Kutta (4,5) and finite difference technique and found it in good compliance. From the obtained results, we observed that the homogeneous heat flux has a greater impact on the temperature at the outer surface of the skin, but the sinusoidal heat flux has a greater impact on the temperature of the subcutaneous layer and inner tissue. It is found that there is no burn injury in the first type of heat source (Tw=44°C), but it may occur in the second and third types of heat sources. It has been observed that by raising the blood perfusion rate and reducing the values of reference metabolic heat, coefficient of thermal conductivity, and heat fluxes, we can manage and reduce burn injuries and achieve hyperthermia temperature.


Assuntos
Queimaduras , Hipertermia Induzida , Humanos , Temperatura Alta , Temperatura , Condutividade Térmica , Modelos Biológicos , Simulação por Computador
14.
Proteins ; 90(5): 1054-1080, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34580920

RESUMO

Understanding the molecular evolution of the SARS-CoV-2 virus as it continues to spread in communities around the globe is important for mitigation and future pandemic preparedness. Three-dimensional structures of SARS-CoV-2 proteins and those of other coronavirusess archived in the Protein Data Bank were used to analyze viral proteome evolution during the first 6 months of the COVID-19 pandemic. Analyses of spatial locations, chemical properties, and structural and energetic impacts of the observed amino acid changes in >48 000 viral isolates revealed how each one of 29 viral proteins have undergone amino acid changes. Catalytic residues in active sites and binding residues in protein-protein interfaces showed modest, but significant, numbers of substitutions, highlighting the mutational robustness of the viral proteome. Energetics calculations showed that the impact of substitutions on the thermodynamic stability of the proteome follows a universal bi-Gaussian distribution. Detailed results are presented for potential drug discovery targets and the four structural proteins that comprise the virion, highlighting substitutions with the potential to impact protein structure, enzyme activity, and protein-protein and protein-nucleic acid interfaces. Characterizing the evolution of the virus in three dimensions provides testable insights into viral protein function and should aid in structure-based drug discovery efforts as well as the prospective identification of amino acid substitutions with potential for drug resistance.


Assuntos
COVID-19 , Pandemias , Aminoácidos , Humanos , Estudos Prospectivos , Proteoma , SARS-CoV-2 , Proteínas Virais/genética , Proteínas Virais/metabolismo
15.
J Therm Biol ; 108: 103278, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36031204

RESUMO

In this article, we discussed a one-dimensional bioheat transfer mathematical model that describes the process of temperature distribution in tissue for the multi-layer skin under the step heating generalized boundary condition. The finite difference scheme is used to estimate the temperature profile along with time and distance. We discussed the stability of the numerical scheme and also validated the accuracy of the numerical code by comparing the present results with the previous reference results. To remove heat from the skin is considered by the surface temperature, heat flux, and ambient temperature to be zero with the help of the unit step like function. Then, we observed that the skin temperature in the second kind boundary condition was slowly decreasing over time as compared to the first and third kind boundary conditions. The temperature or heat flux at the skin surface is assumed to be high then there is negligible effect of the blood perfusion rate on the temperature response over a short time period and the effect of blood perfusion rate is visible when the time duration is long. Effect of blood perfusion rate, heating and after removal of heating, water diffusion, and generalized boundary condition for the analysis of the behavior of temperature response in multi-layer skin are discussed in detail and the results obtained are presented graphically.


Assuntos
Calefação , Modelos Biológicos , Temperatura Alta , Pele , Temperatura Cutânea , Temperatura
16.
J Vector Borne Dis ; 58(3): 285-287, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35170468

RESUMO

Dengue is spread by the bite of infected Aedes aegypti mosquito. It is usually a self-limiting viral infection but sometimes complicates to mortality. In the last few decades, literature has shown that clinical and biochemical profile of dengue is expanding due to the addition of unusual manifestation day by day. Hereby, we report a young male student suffering from dengue complicated to retinal hemorrhage and severe pancytopenia who recovered near fully on treatment.


Assuntos
Aedes , Vírus da Dengue , Dengue , Animais , Cegueira/diagnóstico , Cegueira/etiologia , Dengue/complicações , Dengue/diagnóstico , Humanos , Masculino , Mosquitos Vetores
17.
J Synchrotron Radiat ; 27(Pt 2): 545-550, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32153296

RESUMO

X-ray absorption near-edge structure (XANES) imaging is a powerful tool to visualize the chemical state distribution of transition-metal-based materials at synchrotron radiation facilities. In recent years, the electrochemical working rechargeable battery has been the most studied material in XANES imaging owing to the large increase of portable electronics and electric vehicles. This work acknowledges the importance of battery analysis and has developed the XANES imaging system on BL7C at Pohang Light Source-II (PLS-II). BL7C employs an undulator taper configuration to obtain an energy band >130 eV near the K-absorption edge of the target element with a minimum energy interval >0.2 eV. While measuring energy-dependent images, the zone plate translation maintains the best focus, and then various data processes such as background correction, image registration and clustering allow single XANES spectrum extraction and chemical distribution mapping. Here, the XANES imaging process is described, the XANES spectrum quality is identified and the chemical states of the partially charged cathode material used in lithium-ion batteries as an application example are examined.

18.
Pharmacol Res ; 159: 105026, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32562815

RESUMO

Central nervous system (CNS) disorders like Alzheimer's disease (AD), Parkinson disease (PD), stroke, epilepsy, depression, and bipolar disorder have a high impact on both medical and social problems due to the surge in their prevalence. All of these neuronal disorders share some common etiologies including disruption of Ca2+ homeostasis and accumulation of misfolded proteins. These misfolded proteins further disrupt the intracellular Ca2+ homeostasis by disrupting the activity of several ion channels including transient receptor potential (TRP) channels. TRP channel families include non-selective Ca2+ permeable channels, which act as cellular sensors activated by various physio-chemical stimuli, exogenous, and endogenous ligands responsible for maintaining the intracellular Ca2+ homeostasis. TRP channels are abundantly expressed in the neuronal cells and disturbance in their activity leads to various neuronal diseases. Under the pathological conditions when the activity of TRP channels is perturbed, there is a disruption of the neuronal homeostasis through increased inflammatory response, generation of reactive oxygen species, and mitochondrial dysfunction. Therefore, there is a potential of pharmacological interventions targeting TRP channels in CNS disorders. This review focuses on the role of TRP channels in neurological diseases; also, we have highlighted the current insights into the pharmacological modulators targeting TRP channels.


Assuntos
Fármacos do Sistema Nervoso Central/uso terapêutico , Doenças do Sistema Nervoso Central/tratamento farmacológico , Sistema Nervoso Central/efeitos dos fármacos , Moduladores de Transporte de Membrana/uso terapêutico , Canais de Potencial de Receptor Transitório/antagonistas & inibidores , Animais , Sinalização do Cálcio , Sistema Nervoso Central/metabolismo , Sistema Nervoso Central/fisiopatologia , Fármacos do Sistema Nervoso Central/efeitos adversos , Doenças do Sistema Nervoso Central/metabolismo , Doenças do Sistema Nervoso Central/fisiopatologia , Humanos , Moduladores de Transporte de Membrana/efeitos adversos , Estresse Oxidativo , Dobramento de Proteína , Espécies Reativas de Oxigênio/metabolismo , Canais de Potencial de Receptor Transitório/metabolismo
19.
Molecules ; 25(17)2020 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-32825307

RESUMO

In the present study, different amounts, i.e., 1-3 v/v% of 1 M ammonium phosphate monobasic, were used as an eco-friendly corrosion inhibitor to mitigate the corrosion of steel rebar exposed to simulated concrete pore (SCP) + 3.5 wt% NaCl solution at a prolonged duration. Potentiodynamic polarization results show that as the amount of inhibitor is increased, the corrosion resistance of steel rebar is increased. The steel rebar exposed to 3% inhibitor-containing SCP + 3.5 wt% NaCl solution exhibited nobler corrosion potential (Ecorr), the lowest corrosion current density (icorr), and 97.62% corrosion inhibition efficiency after 1 h of exposure. The steel rebars exposed to 3% inhibitor-containing SCP + 3.5 wt% NaCl solution revealed higher polarization resistance (Rp) and film resistance (Ro) with exposure periods compared to other samples owing to the formation of passive film. The scanning electron microscopy (SEM) of steel rebar exposed to 3% inhibitor-containing SCP + 3.5 wt% NaCl solution showed homogenous and uniform dendritic passive film which covers all over the surface, whereas, bare, i.e., SCP + 3.5 wt% NaCl solution exposed samples exhibited pitting and irregular morphology. Raman spectroscopy results confirm the formation of goethite (α-FeOOH), maghemite (γ-Fe2O3), and iron phosphate (FePO4) as a passive film onto the steel rebar surface exposed to 3% inhibitor-containing SCP + 3.5 wt% NaCl solution. These phases are responsible for the corrosion mitigation of steel rebar which are very protective, adherent, and sparingly soluble.


Assuntos
Materiais de Construção , Fosfatos/química , Cloreto de Sódio/química , Aço/química , Corrosão
20.
Molecules ; 25(22)2020 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-33213017

RESUMO

Graphene is one of the most favorite materials for materials science research owing to its distinctive chemical and physical properties, such as superior conductivity, extremely larger specific surface area, and good mechanical/chemical stability with the flexible monolayer structure. Graphene is considered as a supreme matrix and electron arbitrator of semiconductor nanoparticles for environmental pollution remediation. The present review looks at the recent progress on the graphene-based metal oxide and ternary composites for photocatalysis application, especially for the application of the environmental remediation. The challenges and perspectives of emerging graphene-based metal oxide nanocomposites for photocatalysis are also discussed.


Assuntos
Grafite/química , Luz , Nanocompostos/química , Semicondutores , Poluentes Químicos da Água/isolamento & purificação , Catálise/efeitos da radiação
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