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1.
Artif Organs ; 48(7): 763-770, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38234162

RESUMO

BACKGROUND: Although acute kidney injury (AKI) has been established as an independent risk factor for in-hospital mortality for patients on veno-arterial (V-A) extracorporeal membranous oxygenation (ECMO), the impact of Kidney Disease Improving Global Outcomes (KDIGO) stages of AKI has yet to be elucidated as a risk factor. METHODS: We conducted a retrospective analysis of patient outcomes based on KDIGO stages of AKI at a single institution. The analysis was a cohort of 179 patients; 66 without AKI, 19 with stage 1 AKI, 18 with stage 2 AKI, and 76 with stage 3 AKI. RESULTS: Every 1-year increase in age was associated with 4% increased odds of mortality at 30 days (95% confidence interval [CI] 1.01, 1.07; p = 0.004). The presence of AKI at any stage was associated with 59% increased odds of 30-day mortality (95% CI 0.81, 3.10; p = 0.176). The presence of stage 1 AKI was associated with a 5% decreased odds of 30-day mortality (95% CI 0.32, 2.89). The presence of stage 2 AKI (odds ratio [OR] 2.29, 95% CI 0.69, 7.55; p = 0.173) and stage 3 AKI (OR 1.68, 95% CI 0.81, 3.46; p = 0.164) was associated with increased odds of 30-day mortality. CONCLUSION: Based on our single-center study, higher KDIGO stages of AKI likely have increased odds of mortality at 30 days. Larger studies are needed to confirm these findings.


Assuntos
Injúria Renal Aguda , Oxigenação por Membrana Extracorpórea , Mortalidade Hospitalar , Humanos , Oxigenação por Membrana Extracorpórea/métodos , Oxigenação por Membrana Extracorpórea/efeitos adversos , Injúria Renal Aguda/terapia , Injúria Renal Aguda/mortalidade , Masculino , Estudos Retrospectivos , Feminino , Pessoa de Meia-Idade , Fatores de Risco , Idoso , Resultado do Tratamento , Adulto , Índice de Gravidade de Doença
2.
Bull World Health Organ ; 101(3): 179-190, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36865603

RESUMO

Objective: To describe the changes in tuberculosis case notifications by the private sector after implementation of the Joint Effort for Elimination of Tuberculosis project in India in 2018. Methods: We retrieved data from the project recorded in India's national tuberculosis surveillance system. We analysed data on 95 project districts in six states (Andhra Pradesh, Himachal Pradesh, Karnataka, Punjab including Chandigarh, Telangana and West Bengal) to assess changes in the number of tuberculosis notifications, private provider notifiers and microbiological confirmations of cases from 2017 (baseline) to 2019. We compared case notification rates in districts where the project was implemented with the rates in districts where it was not. Findings: From 2017 to 2019, tuberculosis notifications increased by 138.1% (from 44 695 to 106 404), and case notification rates more than doubled from 20 to 44 per 100 000 population. The number of private notifiers increased by over threefold, from 2912 to 9525, during this period. The number of microbiologically confirmed pulmonary and extra-pulmonary tuberculosis cases notified increased by more than two times (from 10 780 to 25 384) and nearly three times (from 1477 to 4096), respectively. The districts where the project was implemented showed a 150.3% increase in case notification rates per 100 000 population from 2017 to 2019 (from 16.8 to 41.9) while in non-project districts, this increase was only 89.8% (from 6.1 to 11.6). Conclusion: The substantial increase in tuberculosis notifications demonstrate the value of the project in engaging the private sector. Scaling up these interventions is important to consolidate and extend these gains towards tuberculosis elimination.


Assuntos
Tuberculose Extrapulmonar , Tuberculose , Humanos , Índia/epidemiologia , Tuberculose/epidemiologia , Tuberculose/prevenção & controle , Setor Privado , Registros
3.
Perfusion ; 38(5): 1095-1097, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-35442104

RESUMO

A 61-year-old male presented with a history of ischemic cardiomyopathy requiring left ventricular assist device (LVAD) implantation 9 months prior to presentation. The patient was on aspirin and warfarin as part of his LVAD management. The patient had chest pain and was found to have non-ST elevation myocardial infarction. Despite being on warfarin, a subtherapeutic international normalized ratio of 1.6 was measured on admission. Lactate dehydrogenase was 694 U/L (12-146) and high-sensitivity troponin peaked at 47,093 ng/L. Left heart catheterization revealed an extensive aortic root thrombus (AT). AT is an uncommon cause of thromboembolic events in long-term LVAD patients. Thrombotic events in LVAD patients are pump thrombosis, cerebrovascular accidents, heparin-induced thrombocytopenia, and rarely, AT. There is no well-described management of such a rare complication. In our report, we suggest a multidisciplinary approach and consideration of conservative treatment of these patients.


Assuntos
Coração Auxiliar , Infarto do Miocárdio , Trombose , Masculino , Humanos , Pessoa de Meia-Idade , Varfarina , Coração Auxiliar/efeitos adversos , Aorta Torácica , Trombose/etiologia , Infarto do Miocárdio/etiologia
4.
J Infect Dis ; 226(10): 1852-1856, 2022 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-35932228

RESUMO

In mice, pneumococcal polysaccharide (PPS) vaccines generate antigen-specific immunoglobulin M (IgM) and immunoglobulins G1, G2, and G3. Antibody and complement-dependent opsonophagocytosis correlates with the protection induced by PPS vaccines in vivo. Since IgM is a very efficient immunoglobulin isotype in activating the complement system, we evaluated whether anti-PPS IgM alone is sufficient to confer protective immunity to Streptococcus pneumoniae. We found that immunization of wild-type and activation-induced cytidine deaminase-deficient mice capable of producing only IgM with Pneumovax 23 generated comparable anti-PPS IgM and resistance to lethal systemic challenge with S pneumoniae. These data suggest that an IgM response to PPS vaccines is sufficient for conferring immunity.


Assuntos
Anticorpos Antibacterianos , Infecções Pneumocócicas , Camundongos , Animais , Imunoglobulina M , Vacinas Pneumocócicas , Streptococcus pneumoniae , Formação de Anticorpos , Infecções Pneumocócicas/prevenção & controle , Polissacarídeos Bacterianos
5.
J Phys Chem A ; 126(8): 1345-1359, 2022 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-35188378

RESUMO

Nanoclusters are materials of paramount catalytic importance. Among various unique properties featured by nanoclusters, a pronounced relativistic effect can be a decisive parameter in governing their catalytic activity. A concise study delineating the role of relativistic effects in nanocluster catalysis is carried by investigating the oxygen reduction reaction (ORR) activity of a Pt7 subnanometer cluster. Global optimization analysis shows the critical role of spin-orbit coupling (SOC) in regulating the relative stability between structural isomers of the cluster. An overall improved ORR adsorption energetics and differently scaled adsorption-induced structural changes are identified with SOC compared to a non-SOC scenario. Ab initio atomistic thermodynamics analysis predicted nearly identical phase diagrams with significant structural differences for high coverage oxygenated clusters under realistic conditions. Though inclusion of SOC does not bring about drastic changes in the overall catalytic activity of the cluster, it is having a crucial role in governing the rate-determining step, transition-state configuration, and energetics of elementary reaction pathways. Furthermore, a statistical ensemble-based approach illustrates the strong contribution of low-energy local minimum structural isomers to the total ORR activity, which is significantly scaled up along the activity improving direction within the SOC framework. The study provides critical insights toward the importance of relativistic effects in determining various catalytic activity relevant features of nanoclusters.

6.
J Comput Chem ; 42(27): 1944-1958, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34309891

RESUMO

Metal nanoclusters are an important class of materials for catalytic applications. Sub nanometer clusters are relatively less explored for their catalytic activity on account of undercoordinated surface structure. Taking this into account, we studied platinum-based sub nanometer clusters for their catalytic activity for oxygen reduction reaction (ORR). A comprehensive analysis with global optimization is carried out for structural prediction of the platinum clusters. The energetic and electronic properties of interactions of clusters with reaction intermediates are investigated. The role of structural sensitivity in the dynamics of clusters is unraveled, and unique intermediate specific interactions are identified. ORR energetics is examined, and exceptional activity for sub nanometer clusters are observed. An inverse size versus activity relationship is identified, challenging the conventional trends followed by larger nanoclusters. The principal role of atomicity in governing the catalytic activity of nanoclusters is illustrated. The structural norms governing the sub nanometer cluster activity are shown to be markedly different from larger nanoclusters.

7.
Inorg Chem ; 60(24): 19270-19277, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34882397

RESUMO

The structure-property correlation of a series of silver nanoclusters (NCs) is essential to understand the origin of photophysical properties. Here, we report a series of face-centered cubic (fcc)-based silver NCs by varying the halogen atom in the thiolate ligand to investigate the influence of the halide atoms on the electronic structure. These are {Ag14(FBT)12(PPh3)8·(solvent)x} (NC-1), Ag14(CBT)12(PPh3)8 (NC-2), and Ag14(BBT)12(PPh3)8 (NC-3), where 4-fluorothiophenol (FBT), 4-chlorothiophenol (CBT), and 4-bromothiophenol (BBT) have been utilized as thiolate ligands, respectively. Interestingly, the optical and electrochemical bandgap values of these NCs nicely correlated with the electronic effect of the halides, which is governed by the intracluster and interclusters π-π interactions. These clusters are emissive at room temperature and the luminescence intensity increases with the lowering of temperature. The short lifetime data suggest that the emission is predominantly originating due to the interband relaxation (d → sp) of the Ag cores. Femtosecond transient absorption (TA) spectra revealed similar types of decay profiles for NC-2 and NC-3 and longer decay time for NC-2. The relaxation dominates the decay profile to the surface states and most of the excited-state energy dissipates via this process. This supports the molecular-like dynamics of these series of NCs with an fcc core. This overview shed light on an in-depth understanding of ligand's role in luminescence and transient absorption spectra.

8.
Infect Immun ; 86(9)2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29967094

RESUMO

B cell antigen receptor (BCR) diversity increases by several orders of magnitude due to the action of terminal deoxynucleotidyl transferase (TdT) during V(D)J recombination. Unlike adults, infants have limited BCR diversity, in part due to reduced expression of TdT. Since human infants and young mice respond poorly to polysaccharide vaccines, such as the pneumococcal polysaccharide vaccine Pneumovax23 and Vi polysaccharide (ViPS) of Salmonella enterica serovar Typhi, we tested the contribution of TdT-mediated BCR diversity in response to these vaccines. We found that TdT+/- and TdT-/- mice generated comparable antibody responses to Pneumovax23 and survived Streptococcus pneumoniae challenge. Moreover, passive immunization of B cell-deficient mice with serum from Pneumovax23-immunized TdT+/- or TdT-/- mice conferred protection. TdT+/- and TdT-/- mice generated comparable levels of anti-ViPS antibodies and antibody-dependent, complement-mediated bactericidal activity against S Typhi in vitro To test the protective immunity conferred by ViPS immunization in vivo, TdT+/- and TdT-/- mice were challenged with a chimeric Salmonella enterica serovar Typhimurium strain expressing ViPS, since mice are nonpermissive hosts for S Typhi infection. Compared to their unimmunized counterparts, immunized TdT+/- and TdT-/- mice challenged with ViPS-expressing S Typhimurium exhibited a significant reduction in the bacterial burden and liver pathology. These data suggest that the impaired antibody response to the Pneumovax23 and ViPS vaccines in the young is not due to limited TdT-mediated BCR diversification.


Assuntos
DNA Nucleotidilexotransferase/imunologia , Vacinas Pneumocócicas/imunologia , Polissacarídeos Bacterianos/imunologia , Receptores de Antígenos de Linfócitos B/imunologia , Vacinas Tíficas-Paratíficas/imunologia , Fatores Etários , Animais , Anticorpos Antibacterianos/sangue , Anticorpos Antibacterianos/imunologia , Antígenos de Bactérias/imunologia , Carga Bacteriana , DNA Nucleotidilexotransferase/genética , Imunização Passiva , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Salmonella typhi/imunologia , Ensaios de Anticorpos Bactericidas Séricos , Streptococcus pneumoniae/imunologia , Vacinação
9.
Clin Orthop Relat Res ; 475(12): 3090-3099, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28948516

RESUMO

BACKGROUND: Version correction via eccentric reaming reduces clinically important retroversion in Walch type B2 glenoids (those with substantial glenoid retroversion and a second, sclerotic neoglenoid cavity) before total shoulder arthroplasty (TSA). Clinically, an increased risk of glenoid component loosening in B2 glenoids was hypothesized to be the result of compromised glenoid bone quality attributable to eccentric reaming. However, no established guidelines exist regarding how much version correction can be applied without compromising the quality of glenoid bone. QUESTIONS/PURPOSES: (1) How does version correction correlate to the reaming depth and the volume of resected bone during eccentric reaming of B2 glenoids? (2) How does version correction affect the density of the remaining glenoid bone? (3) How does version correction affect the spatial distribution of high-quality bone in the remaining glenoid? METHODS: CT scans of 25 patients identified with Walch type B2 glenoids (age, 68 ± 9 years; 14 males, 11 females) were selected from a cohort of 111 patients (age, 69 ± 10 years; 50 males, 61 females) with primary shoulder osteoarthritis who underwent TSA. Virtual TSA with version corrections of 0°, 5°, 10°, and 15° was performed on 25 CT-reconstructed three-dimensional models of B2 scapulae. After simulated eccentric reaming at each version correction angle, bone density (Hounsfield units [HUs]) was analyzed in five adjacent 1-mm layers under the reamed glenoid surface. Remaining high-quality bone (> 650 HUs) distribution in each 1-mm layer at different version corrections was observed on spatial distribution maps. RESULTS: Larger version corrections required more bone resection, especially from the anterior glenoid. Mean bone densities in the first 1-mm bone bed under the reamed surface were lower with 10° (523.3 ± 79.9 HUs) and 15° (479.5 ± 81.0 HUs) version corrections relative to 0° (0°, 609.0 ± 103.9 HUs; mean difference between 0° and 15°, 129.5 HUs [95% CI, 46.3-212.8 HUs], p < 0.001; mean difference between 0° and 10°, 85.7 HUs [95% CI, 8.6-162.9 HUs], p = 0.021) version correction. Similar results were observed for the second 1-mm bone bed. Spatial distribution maps qualitatively showed a decreased frequency of high-quality bone in the anterior glenoid as version correction increased. CONCLUSIONS: A version correction as low as 10° was shown to reduce the density of the glenoid bone bed for TSA glenoid fixation in our computational study that simulated reaming on CT-reconstructed B2 glenoid models. Increased version correction resulted in gradual depletion of high-quality bone from the anterior region of B2 glenoids. CLINICAL RELEVANCE: This computational study of eccentric reaming of the glenoid before TSA quantitatively showed glenoid bone quality is sensitive to version correction via simulated eccentric reaming. The bone density results of our study may benefit surgeons to better plan TSA on B2 glenoids needing durable bone support, and help to clarify goals for development of precision surgical tools.


Assuntos
Artroplastia de Substituição/métodos , Cavidade Glenoide/cirurgia , Osteoartrite/cirurgia , Osteotomia/métodos , Modelagem Computacional Específica para o Paciente , Articulação do Ombro/cirurgia , Cirurgia Assistida por Computador , Idoso , Artroplastia de Substituição/efeitos adversos , Artroplastia de Substituição/instrumentação , Densidade Óssea , Feminino , Cavidade Glenoide/diagnóstico por imagem , Cavidade Glenoide/fisiopatologia , Humanos , Imageamento Tridimensional , Masculino , Pessoa de Meia-Idade , Osteoartrite/diagnóstico por imagem , Osteoartrite/fisiopatologia , Osteotomia/efeitos adversos , Desenho de Prótese , Interpretação de Imagem Radiográfica Assistida por Computador , Articulação do Ombro/diagnóstico por imagem , Articulação do Ombro/fisiopatologia , Prótese de Ombro , Cirurgia Assistida por Computador/efeitos adversos , Tomografia Computadorizada por Raios X , Resultado do Tratamento
10.
ACS Nano ; 18(16): 10738-10757, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38609349

RESUMO

Biomolecular condensates play important roles in a wide array of fundamental biological processes, such as cellular compartmentalization, cellular regulation, and other biochemical reactions. Since their discovery and first observations, an extensive and expansive library of tools has been developed to investigate various aspects and properties, encompassing structural and compositional information, material properties, and their evolution throughout the life cycle from formation to eventual dissolution. This Review presents an overview of the expanded set of tools and methods that researchers use to probe the properties of biomolecular condensates across diverse scales of length, concentration, stiffness, and time. In particular, we review recent years' exciting development of label-free techniques and methodologies. We broadly organize the set of tools into 3 categories: (1) imaging-based techniques, such as transmitted-light microscopy (TLM) and Brillouin microscopy (BM), (2) force spectroscopy techniques, such as atomic force microscopy (AFM) and the optical tweezer (OT), and (3) microfluidic platforms and emerging technologies. We point out the tools' key opportunities, challenges, and future perspectives and analyze their correlative potential as well as compatibility with other techniques. Additionally, we review emerging techniques, namely, differential dynamic microscopy (DDM) and interferometric scattering microscopy (iSCAT), that have huge potential for future applications in studying biomolecular condensates. Finally, we highlight how some of these techniques can be translated for diagnostics and therapy purposes. We hope this Review serves as a useful guide for new researchers in this field and aids in advancing the development of new biophysical tools to study biomolecular condensates.


Assuntos
Condensados Biomoleculares , Condensados Biomoleculares/química , Condensados Biomoleculares/metabolismo , Microscopia de Força Atômica , Pinças Ópticas , Humanos , Microscopia/métodos
11.
Chem Sci ; 15(25): 9823-9829, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38939161

RESUMO

Transformation chemistry of atomically precise metal nanoclusters has emerged as a novel strategy for fundamental research on the structure-property correlations of nanomaterials. However, a thorough understanding of the transformation mechanism is indeed necessary to understand the structural growth patterns and corresponding property evolutions in nanoclusters. Herein, we present the ligand-exchange-induced transformation of the [Au23(SR)16]- (8e-) nanocluster to the [Au25(SR')18]- (8e-) nanocluster, through the Au23(SR)17 (6e-) intermediate species. Identification of this key intermediate through a partially reversible transformation helped in a detailed investigation into the transformation mechanism with atomic precision. Moreover, photophysical studies carried out on this Au23(SR)17 species, which only differs by a single ligand from that of the [Au23(SR)16]- nanocluster reveal the property evolutions at the slightest change in the nanocluster structure.

12.
Psychopharmacol Bull ; 54(2): 28-33, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38601836

RESUMO

As global aging becomes more prominent, neurocognitive disorders (NCD) incidence has increased. Patients with NCD usually have an impairment in one or more cognitive domains, such as attention, planning, inhibition, learning, memory, language, visual perception, and spatial or social skills. Studies indicate that 50-80% of these adults will develop neuropsychiatric symptoms (NPS), such as apathy, depression, anxiety, disinhibition, delusions, hallucinations, and aberrant motor behavior. The progression of NCD and subsequent NPS requires tremendous care from trained medical professionals and family members. The behavioral symptoms are often more distressing than cognitive changes, causing caregiver distress/depression, more emergency room visits and hospitalizations, and even earlier institutionalization. This signifies the need for early identification of individuals at higher risk of NPS, understanding the trajectory of their NCD, and exploring treatment modalities. In this case report and review, we present an 82-year-old male admitted to our facility for new-onset symptoms of depression, anxiety, and persecutory delusions. He has no significant past psychiatric history, and his medical history is significant for extensive ischemic vascular disease requiring multiple surgeries and two episodes of cerebrovascular accident (CVA). On further evaluation, the patient was diagnosed with major NCD, vascular subtype. We discuss differential diagnoses and development of NPS from NCD in order to explain the significance of more thorough evaluation by clinicians for early detection and understanding of NCD prognosis.


Assuntos
Delusões , Doenças Vasculares , Idoso de 80 Anos ou mais , Humanos , Masculino , Delusões/etiologia , Depressão/etiologia , Alucinações , Transtornos Neurocognitivos , Doenças Vasculares/complicações
13.
Cardiovasc Revasc Med ; 53S: S171-S173, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-35779996

RESUMO

Major vascular complications after transcatheter aortic valve replacement (TAVR) are a pertinent issue and associated with increased morbidity and mortality. We herein describe a case of acute limb ischemia following the administration of protamine sulfate (PS) that was administered to mitigate a bleeding complication post-failure of a vascular access closure device. PS should be used cautiously for the prevention or management of bleeding-site complications following TAVR. The patient described in this case has consented to having his case described in this manuscript.


Assuntos
Estenose da Valva Aórtica , Trombose , Substituição da Valva Aórtica Transcateter , Humanos , Protaminas/efeitos adversos , Estenose da Valva Aórtica/cirurgia , Fatores de Risco , Resultado do Tratamento , Trombose/diagnóstico por imagem , Trombose/etiologia , Valva Aórtica/cirurgia
14.
Nanoscale ; 15(18): 8141-8147, 2023 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-37070944

RESUMO

We present the fabrication and use of a film of a carborane-thiol-protected tetranuclear copper cluster with characteristic orange luminescence using ambient electrospray deposition (ESD). Charged microdroplets of the clusters produced by an electrospray tip deposit the clusters at an air-water interface to form a film. Different microscopic and spectroscopic techniques characterized the porous surface structure of the film. Visible and rapid quenching of the emission of the film upon exposure to 2-nitrotoluene (2-NT) vapours under ambient conditions was observed. Density functional theory (DFT) calculations established the favourable binding sites of 2-NT with the cluster. Desorption of 2-NT upon heating recovered the original luminescence, demonstrating the reusability of the sensor. Stable emission upon exposure to different organic solvents and its quenching upon exposure to 2,4-dinitrotoluene and picric acid showed selectivity of the film to nitroaromatic species.

15.
PLoS One ; 18(9): e0291269, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37708211

RESUMO

BACKGROUND: Tata MD CHECK SARS-CoV-2 kit 1.0, a CRISPR based reverse transcription PCR (TMC-CRISPR) test was approved by Indian Council of Medical Research (ICMR) for COVID-19 diagnosis in India. To determine the potential for rapid roll-out of this test, we conducted performance characteristic and an operational feasibility assessment (OFA) at a tertiary care setting. INTERVENTION: The study was conducted at an ICMR approved COVID-19 RT-PCR laboratory of King Edward Memorial (KEM) hospital, Mumbai, India. The TMC-CRISPR test was evaluated against the gold-standard RT-PCR test using the same RNA sample extracted from fresh and frozen clinical specimens collected from COVID-19 suspects for routine diagnosis. TMC-CRISPR results were determined manually and using the Tata MD CHECK application. An independent agency conducted interviews of relevant laboratory staff and supervisors for OFA. RESULTS: Overall, 2,332 (fresh: 2,121, frozen: 211) clinical specimens were analysed of which, 140 (6%) were detected positive for COVID-19 by TMC-CRISPR compared to 261 (11%) by RT-PCR. Overall sensitivity and specificity of CRISPR was 44% (95% CI: 38.1%-50.1%) and 99% (95% CI: 98.2%-99.1%) respectively when compared to RT-PCR. Discordance between TMC-CRISPR and RT-PCR results increased with increasing Ct values and corresponding decreasing viral load (range: <20% to >85%). In the OFA, all participants indicated no additional requirements of training to set up RT PCR. However, extra post-PCR steps such as setting up the CRISPR reaction and handling of detection strips were time consuming and required special training. No significant difference was observed between manual and mobile app-based readings. However, issues such as erroneous results, difficulty in interpretation of faint bands, internet connectivity, data safety and security were highlighted as challenges with the app-based readings. CONCLUSION: The evaluated version-Tata MD CHECK SARS-CoV-2 kit 1.0 of TMC-CRISPR test cannot be considered as an alternative to the RT-PCR. There is a definite scope for improvement in this assay.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/diagnóstico , Teste para COVID-19 , Estudos de Viabilidade , Testes Diagnósticos de Rotina
16.
Nanoscale ; 15(31): 13102-13109, 2023 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-37501634

RESUMO

Surface-protecting ligands can regulate the structure of a cluster's core either through electronic or steric effects. However, the influence of the steric effect along with the electronic effect over controlling the structure during ligand exchange reactions remains elusive. To understand this, we have carried out ligand exchange on [Au23(CHT)16]- (CHT: cyclohexane thiol) using aromatic thiolates where we have tuned the bulkiness at the para position of the thiolate group on the incoming ligands. The outcome of the experiments reveals that each of the ligands in the chosen series is precisely selective towards the parent cluster transformation through specific intermediates. The ligand with more steric crowding directed the reaction pathway to have Au28 nanocluster as the major product while Au36 was the final product obtained with the gradual decrease of bulkiness over the ligand. The combined experimental and theoretical results elucidated the mechanism of the reaction pathways, product formation, and their stability. Indeed, this study with the series of ligands will add up to the ligand library, where we can decide on the ligand to obtain our desired cluster for specific applications through the ligand exchange reaction.

17.
J Invest Dermatol ; 143(5): 699-710.e10, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36528128

RESUMO

Systemic sclerosis is a fibrotic disease that initiates in the skin and progresses to internal organs, leading to a poor prognosis. Unraveling the etiology of a chronic, multifactorial disease such as systemic sclerosis has been aided by various animal models that recapitulate certain aspects of the human pathology. We found that the transcription factor SNAI1 is overexpressed in the epidermis of patients with systemic sclerosis, and a transgenic mouse recapitulating this expression pattern is sufficient to induce many clinical features of the human disease. Using this mouse model as a discovery platform, we have uncovered a critical role for the matricellular protein Mindin (SPON2) in fibrogenesis. Mindin is produced by SNAI1 transgenic skin keratinocytes and aids fibrogenesis by inducing early inflammatory cytokine production and collagen secretion in resident dermal fibroblasts. Given the dispensability of Mindin in normal tissue physiology, targeting this protein holds promise as an effective therapy for fibrosis.


Assuntos
Fibroblastos , Escleroderma Sistêmico , Camundongos , Animais , Humanos , Fibroblastos/metabolismo , Escleroderma Sistêmico/patologia , Pele/patologia , Proteínas da Matriz Extracelular/metabolismo , Fibrose , Camundongos Transgênicos , Modelos Animais de Doenças , Proteínas de Neoplasias/metabolismo
18.
ACS Phys Chem Au ; 2(2): 125-135, 2022 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-36855504

RESUMO

Large-scale ammonia production through sustainable strategies from naturally abundant N2 under ambient conditions represents a major challenge from a future perspective. Ammonia is one of the promising carbon-free alternative energy carriers. The high energy required for N≡N bond dissociation during the Haber-Bosch process demands extreme reaction conditions. This problem could be circumvented by tuning Fe catalyst composition with the help of an induced ligand effect on the surface. In this work, we utilized density functional theory calculations on the Fe(110) surface alloyed with first-row transition-metal (TM) series (Fe-TM) to understand the catalytic activity that facilitates the electrochemical nitrogen reduction reaction (NRR). We also calculated the selectivity against the competitive hydrogen evolution reaction (HER) under electrochemical conditions. The calculated results are compared with those from earlier reports on the periodic Fe(110) and Fe(111) surfaces, and also on the (110) surface of the Fe85 nanocluster. Surface alloying with late TMs (Co, Ni, Cu) shows an improved NRR activity, whereas the low exchange current density observed for Fe-Co indicates less HER activity among them. Considering various governing factors, Fe-based alloys with Co (Fe-Co) showed enhanced overall performance compared to the periodic surface as well as other pure iron-based structures previously reported. Therefore, the iron-alloy based structured catalysts may also provide more opportunities in the future for enhancing NRR performance via electrochemical reduction pathways.

19.
Chem Sci ; 13(25): 7616-7625, 2022 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-35872832

RESUMO

Structural elucidation of atom-precise thiolate-protected copper nanoclusters (Cu NCs) containing Cu(0) is quite challenging. Here, we report a new adamantane-thiol-protected NC, [Cu18H3(S-Adm)12(PPh3)4Cl2] (Cu18), which represents the first observation of a rare mononuclear Cu(0)-containing Cu10H3Cl2 core that is constructed via kernel fusion through vertex sharing of the Platonic-solid- and Johnson-solid-geometry-like kernels and hydride-bridging. The unique core is surrounded by a Cu8S12P4 metal-ligand motif shell and adopts a butterfly-like structure. In comparison to its closest structural analogue, the predominant effect of the principal Cu atom vacancy-induced structural rearrangement is evidenced. The occupied orbitals of this NC have a major d-orbital contribution to the distorted Cu6 octahedral kernel, whereas unoccupied orbitals owe a contribution to the distorted Cu5 square-pyramidal kernel. Thus, the charge transfer phenomenon is uniquely instigated between the two fused kernels through Cu(d) → Cu(d) transition via the Cu(0) center. This NC exhibits violet emission due to kernel-dominated relaxation at room temperature, which is further enhanced by confining the surface protecting ligands through recognition-site-specific host-guest supramolecular adduct formation by ß-cyclodextrin. The unique electronic structure of this NC further facilitates its application toward photocurrent generation. Thus, this study offers a unique strategy for the controllable synthesis of a Cu(0)-containing Cu NC, which enables atomic-level insights into their optoelectronic properties.

20.
Biosaf Health ; 4(5): 347-363, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35765656

RESUMO

The outbreak of coronavirus disease 2019 (COVID-19) has adversely affected the public domain causing unprecedented cases and high mortality across the globe. This has brought back the concept of biosafety into the spotlight to solve biosafety problems in developing diagnostics and therapeutics to treat COVID-19. The advances in nanotechnology and material science in combination with medicinal chemistry have provided a new perspective to overcome this crisis. Herein, we discuss the efforts of researchers in the field of material science in developing personal protective equipment (PPE), detection devices, vaccines, drug delivery systems, and medical equipment. Such a synergistic approach of disciplines can strengthen the research to develop biosafety products in solving biosafety problems.

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