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1.
Indian J Tuberc ; 71(4): 471-475, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39278682

RESUMO

Silico-Tuberculosis (silico-TB) is a severe combination of tuberculosis and silicosis, caused by occupational exposure to fine crystalline silica dust, which has become a global health concern. This comprehensive review compiles the updated knowledge regarding pathophysiology, clinical manifestations, important diagnostic techniques, treatment aspects, and challenges in understanding silico-TB. The review compiles the disease's history and epidemiology, highlighting a lack of data owing to poor monitoring and healthcare particularly in low- and middle-income countries like India. Further weak safety regulations, lack of preventative measures, and inadequate education increase the rates of silico-TB. The pathophysiology shows how silica particles impair the immune system and stimulate Th2 cells and M2 macrophages, which exacerbate TB, while inhibiting Th1 cells and M1 macrophages, which fight against the disease. Subsequently, it can be difficult to distinguish current TB from pre-existing silicosis. In cases where sputum and X-ray results are negative, chest CT scans may be helpful since radiographic screening identifies TB earlier than sputum assessment. Isoniazid, rifampicin, or both minimize the risk of active tuberculosis in people with silicosis. Consistent anti-tuberculosis drug therapy is recommended for 8-9 months to stop recurrence. The assessment recommends integrating silicosis and TB control initiatives to fight this combined health issue.


Assuntos
Silicose , Humanos , Silicose/diagnóstico , Antituberculosos/uso terapêutico , Antituberculosos/efeitos adversos , Exposição Ocupacional/efeitos adversos , Índia/epidemiologia , Silicotuberculose/diagnóstico
2.
Phys Rev Lett ; 133(8): 083801, 2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39241710

RESUMO

We show a new class of optical silk torsion pendulum (TOP) with zepto-Newton-meter (zNm) sensitivity achieved by exploiting hitherto unknown ultrasoft twist response of tough silk fibers in ultrahigh vacuum. We demonstrate several macroscopic microgram TOPs using three different silk types showing 6 orders of magnitude wide range of sensitivity calibrated using up to zNm optical torques. Remarkably, a nanoscale diameter capture silk exhibits about 20 fNm/rad torsion constant with low damping and responds to sub-400 zNm impulses over many oscillation cycles. We have isolated sub-3.0±0.2 zNm/s torque velocity sensitivity with an integration time of the order of hours. We show systematic measurements of optical torsional damping induced by well-timed subcycle impulses as well as periodic on-off torquing down to 470 zNm amplitude, in quantitative agreement with model simulations. Our calculation suggests that a 100 nm diameter silk nanofibril can open a route to sub-yocto-Nm sensitive macroscopic TOP thereby making silk sensors attractive for real-world ultrasensitive metrology applications.

4.
ACS Pharmacol Transl Sci ; 7(7): 2063-2079, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-39022355

RESUMO

TLR-7/8 agonists are a well-known class of vaccine adjuvants, with a leading example now included in Covaxin, a licensed human COVID-19 vaccine. This thereby provides the opportunity to develop newer, more potent adjuvants based on structure-function studies of these classes of compounds. Imidazoquinoline-based TLR7/8 agonists are the most potent, but when used as a vaccine adjuvant side effects can arise due to diffusion from the injection site into a systemic circulation. In this work, we sought to address this issue through structural modifications in the agonists to enhance their adsorption capacity to the classic adjuvant alum. We selected a potent TLR7-selective agonist, BBIQ (EC50 = 0.85 µM), and synthesized polyphenolic derivatives to assess their TLR7 agonistic activity and adjuvant potential alone or in combination with alum. Most of the phenolic derivatives were more active than BBIQ and, except for 12b, all were TLR7 specific. Although the synthesized compounds were less active than resiquimod, the immunization data on combination with alum, specifically the IgG1, IgG2b and IgG2c responses, were superior in comparison to BBIQ as well as the reference standard resiquimod. Compound 12b was 5-fold more potent (EC50 = 0.15 µM in TLR7) than BBIQ and induced double the IgG response to SARS-CoV-2 and hepatitis antigens. Similarly, compound 12c (EC50 = 0.31 µM in TLR7) was about 3-fold more potent than BBIQ and doubled the IgG levels. Even though compound 12d exhibited low TLR7 activity (EC50 = 5.13 µM in TLR7), it demonstrated superior adjuvant results, which may be attributed to its enhanced alum adsorption capability as compared with BBIQ and resiquimod. Alum-adsorbed polyphenolic TLR7 agonists thereby represent promising combination adjuvants resulting in a balanced Th1/Th2 immune response.

5.
Curr Protoc ; 4(6): e1030, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38923763

RESUMO

Functional characterization of enzymes/proteins requires determination of the binding affinity of small molecules or other biomolecules with the target proteins. Several available techniques, such as proteomics and drug discovery strategies, require a precise and high-throughput assay for rapid and reliable screening of potential candidates for further testing. Surface plasmon resonance (SPR), a well-established label-free technique, directly measures biomolecular affinities. SPR assays require immobilization of one interacting component (ligand) on a conductive metal (mostly gold or silver) and a continuous flow of solution containing potential binding partner (analyte) across the surface. The SPR phenomenon occurs when polarized light excites the electrons at the interface of the metal and the dielectric medium to generate electromagnetic waves that propagate parallel to the surface. Changes in the refractive index due to interaction between the ligand and analyte are measured by detecting the reflected light, providing real-time data on kinetics and specificity. A prominent use of SPR is identifying compounds in crude plant extracts that bind to specific molecules. Procedures that utilize SPR are becoming increasingly applicable outside the laboratory setting, and SPR imaging and localized SPR (LSPR) are cheaper and more portable alternative for in situ detection of plant or mammalian pathogens and drug discovery studies. LSPR, in particular, has the advantage of direct attachment to test tissues in live-plant studies. Here, we describe three protocols utilizing SPR-based assays for precise analysis of protein-ligand interactions. © 2024 Wiley Periodicals LLC. Basic Protocol 1: SPR comparison of binding affinities of viral reverse transcriptase polymorphisms Basic Protocol 2: SPR screening of crude plant extract for protein-binding agents Basic Protocol 3: Localized SPR-based antigen detection using antibody-conjugated gold nanoparticles.


Assuntos
Ressonância de Plasmônio de Superfície , Ressonância de Plasmônio de Superfície/métodos , Ligantes , Ligação Proteica , Proteínas/química , Proteínas/metabolismo , Ouro/química
6.
Biomed J ; : 100746, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38734408

RESUMO

Mpox is a zoonotic disease caused by the monkeypox virus (MPV), primarily found in Central and West African countries. The typical presentation of the disease before the 2022 mpox outbreak includes a febrile prodrome 5-13 days post-exposure, accompanied by lymphadenopathy, malaise, headache, and muscle aches. Unexpectedly, during the 2022 outbreak, several cases of atypical presentations of the disease were reported, such as the absence of prodromal symptoms and the presence of genital skin lesions suggestive of sexual transmission. As per the World Health Organization (WHO), as of March 20, 2024, 94,707 cases of mpox were reported worldwide, resulting in 181 deaths (22 in African endemic regions and 159 in non-endemic countries). The United States Centers for Disease Control and Prevention (CDC) reports a total of 32,063 cases (33.85% of total cases globally), with 58 deaths (32.04% of global deaths) due to mpox. Person-to-person transmission of mpox can occur through respiratory droplets and sustained close contact. However, during the 2022 outbreak of mpox, a high incidence of anal and perianal lesions among MSMs indicated sexual transmission of MPV as a major route of transmission. Since MSMs are disproportionately at risk for HIV transmission, this review discusses the risk factors, transmission patterns, pathogenesis, vaccine, and treatment options for mpox among MSM and people living with HIV (PLWH). Furthermore, we provide a brief perspective on the evolution of the MPV in immunocompromised people like PLWH.

7.
Antiviral Res ; 227: 105904, 2024 07.
Artigo em Inglês | MEDLINE | ID: mdl-38729306

RESUMO

Despite considerable progress in developing vaccines and antivirals to combat COVID-19, the rapid mutations of the SARS-CoV-2 genome have limited the durability and efficacy of the current vaccines and therapeutic interventions. Hence, it necessitates the development of novel therapeutic approaches or repurposing existing drugs that target either viral life cycle, host factors, or both. Here, we report that SRX3177, a potent triple-activity CDK4/6-PI3K-BET inhibitor, blocks replication of the SARS-CoV-2 Omicron variant with IC50 values at sub-micromolar concentrations without any impact on the cell proliferation of Calu-3 cells at and below its IC50 concentration. When SRX3177 is combined with EIDD-1931 (active moiety of a small-molecule prodrug Molnupiravir) or MU-UNMC-2 (a SARS-CoV-2 entry inhibitor) at a fixed doses matrix, a synergistic effect was observed, leading to the significant reduction in the dose of the individual compounds to achieve similar inhibition of SARS-CoV-2 replication. Herein, we report that the combination of SRX3177/MPV or SRX3177/UM-UNMC-2 has the potential for further development as a combinational therapy against SARS-CoV-2 and in any future outbreak of beta coronavirus.


Assuntos
Antivirais , Tratamento Farmacológico da COVID-19 , SARS-CoV-2 , Replicação Viral , SARS-CoV-2/efeitos dos fármacos , Humanos , Antivirais/farmacologia , Replicação Viral/efeitos dos fármacos , Citidina/análogos & derivados , Citidina/farmacologia , Hidroxilaminas/farmacologia , Inibidores de Fosfoinositídeo-3 Quinase/farmacologia , Internalização do Vírus/efeitos dos fármacos , Chlorocebus aethiops , Animais , Leucina/análogos & derivados , Leucina/farmacologia , Células Vero , Sinergismo Farmacológico , Linhagem Celular , Quinase 4 Dependente de Ciclina/antagonistas & inibidores , COVID-19/virologia
8.
bioRxiv ; 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38617336

RESUMO

Formation of biomolecular condensates can be driven by weak multivalent interactions and emergent polymerization. However, the mechanism of polymerization-mediated condensate formation is less studied. We found lateral root cap cell (LRC)-specific SUPPRESSOR OF RPS4-RLD1 (SRFR1) condensates fine-tune primary root development. Polymerization of the SRFR1 N-terminal domain is required for both LRC condensate formation and optimal root growth. Surprisingly, the first intrinsically disordered region (IDR1) of SRFR1 can be functionally substituted by a specific group of intrinsically disordered proteins known as dehydrins. This finding facilitated the identification of functional segments in the IDR1 of SRFR1, a generalizable strategy to decode unknown IDRs. With this functional information we further improved root growth by modifying the SRFR1 condensation module, providing a strategy to improve plant growth and resilience.

9.
Biology (Basel) ; 13(4)2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38666816

RESUMO

DNA polymerases replicate cellular genomes and/or participate in the maintenance of genome integrity. DNA polymerases sharing high sequence homology with E. coli DNA polymerase I (pol I) have been grouped in Family A. Pol I participates in Okazaki fragment maturation and in bacterial genome repair. Since its discovery in 1956, pol I has been extensively studied, primarily to gain deeper insights into the mechanism of DNA replication. As research on DNA polymerases advances, many novel functions of this group of polymerases are being uncovered. For example, human DNA polymerase θ (a Family A DNA pol) has been shown to synthesize DNA using RNA as a template, a function typically attributed to retroviral reverse transcriptase. Increased interest in drug discovery against pol θ has emerged due to its roles in cancer. Likewise, Pol I family enzymes also appear attractive as drug-development targets against microbial infections. Development of antimalarial compounds targeting apicoplast apPOL, an ortholog of Pol I, further extends the targeting of this family of enzymes. Here, we summarize reported drug-development efforts against Family A polymerases and future perspective regarding these enzymes as antibiotic targets. Recently developed techniques, such as artificial intelligence, can be used to facilitate the development of new drugs.

10.
J Prim Health Care ; 16(1): 70-77, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38546768

RESUMO

Introduction Cancer screening programmes for cervical, breast, and colorectal cancer have successfully reduced mortality rates among target groups. However, a large proportion of women and men are unscreened. Aim This review aims to provide an overview of the literature regarding the determinants of cancer screening participation among target groups in Queensland. Methods Electronic databases were searched for studies on determinants of cancer screening participation in Queensland. Retrieved studies were screened, and eligible articles were selected for data extraction. Both peer-reviewed and grey literature studies were included. The determinants of cancer screening participation were classified according to the I-Change model. Results Sixteen out of 75 articles were selected and analysed. Information factors, such as the lack of tailored strategies, determined cancer screening participation. Age, gender, cultural beliefs, fear and past experiences were the most reported predisposing factors to cancer screening participation. Lack of knowledge, misconceptions, low awareness, timely access to service, privacy and confidentiality were mainly reported awareness and motivation factors. Encouragement from health professionals, providing more information and interactions with communities would result in different effects on cancer screening participation among the target groups. Discussion The I-Change model is a valuable tool in mapping the current determinants of cancer screening participation programs. Further research may be needed to fully understand the barriers and facilitators of cancer screening programs.


Assuntos
Detecção Precoce de Câncer , Neoplasias , Masculino , Humanos , Feminino , Queensland , Motivação , Programas de Rastreamento , Neoplasias/diagnóstico , Neoplasias/prevenção & controle
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