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The quality of the buried heterojunction of nickel oxide (NiOX)/perovskite is crucial for efficient charge carrier extraction and minimizing interfacial non-radiative recombination in inverted perovskite solar cells (PSCs). However, NiOX has limitations as a hole transport layer (HTL) due to energy level mismatch, low conduction, and undesirable redox reactions with the perovskite layer, which impede power conversion efficiency (PCE) and long-term stability. In this study, para-amino 2,3,5,6-tetrafluorobenzoic acid (PATFBA) is proposed as a bifacial defect passivator to tailor the NiOX/perovskite interface. The acid group and adjacent fluorine atoms of PATFBA effectively passivate NiOX surface defects, thereby improving its Ni3+/Ni2+ ratio, hole extraction capability, and energy band alignment with perovskite, while also providing active sites for homogenous nucleation. Meanwhile, the amine and adjacent fluorine atomsstabilize the buried perovskite interface by passivating interfacial defects, resulting in higher crystalline perovskite films with supressed non-radaitive recombination. Furthermore, the PATFBA buffer layer prevents redox reactions between Ni3+ and perovskite.These synergistic bi-directional interactions lead to optimized inverted PSCs with a PCE of 20.51% compared to 16.89% for pristine devices and the unencapsulated PATFBA-modified devices exhibit outstanding thermal and long-term stability. This work provides a new engineering approach to buried interfaces through the synergy of functional groups.
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The complex immunosuppressive nature of solid tumor microenvironments poses a significant challenge to generating efficacious and durable anticancer responses. Photoimmunotherapy is a cancer treatment strategy by which an antibody is conjugated with a non-toxic light-activatable dye. Following administration of the conjugate and binding to the target tumor, subsequent local laser illumination activates the dye, resulting in highly specific target cell membrane disruption. Here we demonstrate that photoimmunotherapy treatment elicited tumor necrosis, thus inducing immunogenic cell death characterized by the release of damage-associated molecular patterns (DAMPs). Photoimmunotherapy-killed tumor cells activated dendritic cells (DC), leading to the production of proinflammatory cytokines, T cell stimulation, priming antigen-specific T cells, and durable memory T cell responses, which led complete responder mice to effectively reject new tumors upon rechallenge. PD-1 blockade in combination with photoimmunotherapy enhanced overall anticancer efficacy, including against anti-PD-1-resistant tumors. The combination treatment also elicited abscopal anticancer activity, as observed by reduction of distal, non-illuminated tumors, further demonstrating the ability of photoimmunotherapy to harness local and peripheral T cell responses. With this work we therefore delineate the immune mechanisms of action for photoimmunotherapy and demonstrate the potential for cancer-targeted photoimmunotherapy to be combined with other immunotherapy approaches for augmented, durable anticancer efficacy. Moreover, we demonstrate responses utilizing various immunocompetent mouse models, as well as in vitro data from human cells, suggesting broad translational potential.
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Imunoterapia , Neoplasias , Humanos , Animais , Camundongos , Imunoterapia/métodos , Fototerapia/métodos , Neoplasias/terapia , Modelos Animais de Doenças , Linhagem Celular Tumoral , Microambiente TumoralRESUMO
Mechanistic understanding of DNA recombination in the Cre-loxP system has largely been guided by crystallographic structures of tetrameric synaptic complexes. Those studies have suggested a role for protein conformational dynamics that has not been well characterized at the atomic level. We used solution nuclear magnetic resonance (NMR) spectroscopy to discover the link between intrinsic flexibility and function in Cre recombinase. Transverse relaxation-optimized spectroscopy (TROSY) NMR spectra show the N-terminal and C-terminal catalytic domains (CreNTD and CreCat) to be structurally independent. Amide 15N relaxation measurements of the CreCat domain reveal fast-timescale dynamics in most regions that exhibit conformational differences in active and inactive Cre protomers in crystallographic tetramers. However, the C-terminal helix αN, implicated in assembly of synaptic complexes and regulation of DNA cleavage activity via trans protein-protein interactions, is unexpectedly rigid in free Cre. Chemical shift perturbations and intra- and intermolecular paramagnetic relaxation enhancement (PRE) NMR data reveal an alternative autoinhibitory conformation for the αN region of free Cre, wherein it packs in cis over the protein DNA binding surface and active site. Moreover, binding to loxP DNA induces a conformational change that dislodges the C terminus, resulting in a cis-to-trans switch that is likely to enable protein-protein interactions required for assembly of recombinogenic Cre intasomes. These findings necessitate a reexamination of the mechanisms by which this widely utilized gene-editing tool selects target sites, avoids spurious DNA cleavage activity, and controls DNA recombination efficiency.
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DNA/metabolismo , Integrases/química , Integrases/metabolismo , Sítios de Ligação , Cristalografia por Raios X , DNA/genética , Integrases/genética , Modelos Moleculares , Ligação Proteica , Conformação Proteica , Domínios ProteicosRESUMO
Benzannulation reactions involve construction of a benzene ring from acyclic precursors. This class of reactions offer a versatile and often superior alternative to aromatic substitution for construction of substituted arenes. Selected pioneering and recent reports of various benzannulation reactions are categorised and discussed in this review.
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Microbial association networks are frequently used for understanding and comparing community dynamics from microbiome datasets. Inferring microbial correlations for such networks and obtaining meaningful biological insights, however, requires a lengthy data management workflow, choice of appropriate methods, statistical computations, followed by a different pipeline for suitably visualizing, reporting and comparing the associations. The complexity is further increased with the added dimension of multi-group 'meta-data' and 'inter-omic' functional profiles that are often associated with microbiome studies. This not only necessitates the need for categorical networks, but also integrated and bi-partite networks. Multiple options of network inference algorithms further add to the efforts required for performing correlation-based microbiome interaction studies. We present MetagenoNets, a web-based application, which accepts multi-environment microbial abundance as well as functional profiles, intelligently segregates 'continuous and categorical' meta-data and allows inference as well as visualization of categorical, integrated (inter-omic) and bi-partite networks. Modular structure of MetagenoNets ensures logical flow of analysis (inference, integration, exploration and comparison) in an intuitive and interactive personalized dashboard driven framework. Dynamic choice of filtration, normalization, data transformation and correlation algorithms ensures, that end-users get a one-stop solution for microbial network analysis. MetagenoNets is freely available at https://web.rniapps.net/metagenonets.
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Microbiota , Software , Algoritmos , Humanos , Doenças Inflamatórias Intestinais/microbiologia , MetagenômicaRESUMO
Staufen1 (STAU1) is a dsRNA binding protein mediating mRNA transport and localization, translational control and STAU1-mediated mRNA decay (SMD). The STAU1 binding site (SBS) within human ADP-ribosylation factor1 (ARF1) 3'UTR binds STAU1 and this downregulates ARF1 cytoplasmic mRNA levels by SMD. However, how STAU1 recognizes specific mRNA targets is still under debate. Our structure of the ARF1 SBS-STAU1 complex uncovers target recognition by STAU1. STAU1 dsRNA binding domain (dsRBD) 4 interacts with two pyrimidines and one purine from the minor groove side via helix α1, the ß1-ß2 loop anchors the dsRBD at the end of the dsRNA and lysines in helix α2 bind to the phosphodiester backbone from the major groove side. STAU1 dsRBD3 displays the same binding mode with specific recognition of one guanine base. Mutants disrupting minor groove recognition of ARF1 SBS affect in vitro binding and reduce SMD in vivo. Our data thus reveal how STAU1 recognizes minor groove features in dsRNA relevant for target selection.
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Fator 1 de Ribosilação do ADP/química , Proteínas do Citoesqueleto/química , Motivo de Ligação ao RNA de Cadeia Dupla/genética , RNA de Cadeia Dupla/química , Proteínas de Ligação a RNA/química , Fator 1 de Ribosilação do ADP/genética , Sítios de Ligação/genética , Citoplasma/química , Citoplasma/genética , Proteínas do Citoesqueleto/genética , Humanos , Conformação Proteica , Estabilidade de RNA/genética , RNA de Cadeia Dupla/genética , Proteínas de Ligação a RNA/genéticaRESUMO
Hygiene hypothesis and sanitization are two important pivots of modern civilization. The drinking water should be free from urine and stool contamination. Coliform test is popular for understanding feces contamination. However, understanding urine contamination in drinking water is a difficult task. On the other hand, urine contamination can cause disease like leptospirosis. It occurs mainly in animals and infects humans through contaminated water, food, and soil and causes serious consequences. Rat urine is the most common source of such disease outbreaks. Further, sophisticated laboratories with high-end technologies may not be present at the site of disease outbreaks. In this context, we have proposed a spectrofluorimetric approach to screen urine contamination in water. The screening method can sense up to 156 nl/ml of rat urine.
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Água Potável , Leptospirose , Vigilância em Saúde Pública , Poluição da Água , Animais , Humanos , Ratos , Água Potável/análise , Índia/epidemiologia , Leptospirose/epidemiologia , Espectrometria de Fluorescência , Urina , Poluição da Água/efeitos adversos , Poluição da Água/análise , Vigilância em Saúde Pública/métodosRESUMO
OBJECTIVE: To assess the implementation of a mobile dispensing service to improve opioid users' access to methadone maintenance therapy. METHODS: In March 2019, we started mobile methadone dispensing in an urban underprivileged locality in Delhi, India. The doctor was available only at the main community drug treatment clinic for clinical services, while the nurse dispensed methadone from a converted ambulance. We involved patients in identifying community leaders for sensitization and in deciding the location and timings for dispensing. We conducted a retrospective chart review of the programme data collected during delivery of clinical services. We compared the numbers of patients registered for methadone therapy and their retention and adherence to therapy in the 12-month periods before and after implementation of the mobile service. FINDINGS: The number of patients registered for therapy at the clinic increased from 167 in the year before implementation to 671 in the year after. A significantly higher proportion of patients were retained in therapy at 3, 6 and 9 months after enrolment; 9-month retention rates were 19% (32/167 patients) and 45% (44/97 patients) in the year before and after implementation, respectively. There was no significant difference in patients' adherence to therapy between the two periods. Challenges included providing suitable dispensing hours for patients in employment and concerns of local community near to the dispensing sites. CONCLUSION: It is feasible to dispense methadone by a mobile team in an urban setting, with better retention rates in therapy compared with dispensing through a stationary clinic.
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Analgésicos Opioides/uso terapêutico , Implementação de Plano de Saúde , Metadona/uso terapêutico , Unidades Móveis de Saúde/organização & administração , Transtornos Relacionados ao Uso de Opioides/reabilitação , Adulto , Feminino , Humanos , Índia , Masculino , Pessoa de Meia-Idade , Tratamento de Substituição de Opiáceos , Transtornos Relacionados ao Uso de Opioides/tratamento farmacológico , Avaliação de Programas e Projetos de Saúde , Estudos Retrospectivos , Resultado do TratamentoRESUMO
Tuberculosis, a global threat, is a highly infectious disease intensified by the emergence of drug-resistant strains. In tuberculosis disease spectrum, a typical situation is a dormant or latent phase where a person exposed to Mycobacterium tuberculosis has the reservoir of the disease that may or may not result in an active state. Existence of the dormant state is retarding the eradication of tuberculosis. Transcription of several genes helps M. tuberculosis to survive in nonreplicative mode. DosR transcription factor is the hallmark for this genesis. Diabetes mellitus is a predisposition factor leading to the development of tuberculosis and latent tuberculosis. High plasma insulin concentrations in the prediabetic state can increase the tuberculosis bacterium. On the other hand, antidiabetic drug metformin is known to reduce active tuberculosis disease when provided in combination with antitubercular therapy. However, the effect of the same on latent tuberculosis is still unknown. In the present work using tools of computational biology, we have tried to find the consequence of adding metformin in combination with rifampicin, a well-known antitubercular drug, on molecular mechanisms of latent tuberculosis. We have investigated whether metformin and rifampicin interact with DosR machinery or not. Our results indicate that if metformin-bound DosR-DNA complex binds with rifampicin, it will result in the conversion of active tuberculosis to latent tuberculosis.
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Antituberculosos/farmacologia , Tuberculose Latente/tratamento farmacológico , Metformina/farmacologia , Simulação de Acoplamento Molecular , Mycobacterium tuberculosis/efeitos dos fármacos , Rifampina/farmacologia , Antituberculosos/química , Humanos , Tuberculose Latente/microbiologia , Metformina/química , Testes de Sensibilidade Microbiana , Rifampina/químicaRESUMO
BACKGROUND: Previous studies have shown that the position and presence of mandibular third molars is associated with a high risk of mandibular angle fractures. The aim of this study was to assess the relationship between the position and presence of mandibular third molars and mandibular angle fractures. MATERIAL AND METHODS: A retrospective study consisting of 256 patients who were admitted for treatment of mandibular fractures between January 2016 and January 2018 was undertaken. Patients' data and orthopantomogram radiographs were obtained from their medical record. The predictor variable was the presence and position of mandibular third molars. The position of the third molars was grouped based on the Pell and Gregory classification. The outcome variable was the presence of an angle fracture. Other study variables included age, gender, mechanism of injury, and fracture location. RESULTS: Patients with mandibular third molars had a 2.7 times greater chance of an angle fracture than patients without third molars. Patients with their third molars present at occlusal position C and ramus position level 3 had a higher risk of angle fracture in comparison with other groups. There was a statistically significant variation in the risk of an angle fracture, depending on mandibular third molar position (P < .001). CONCLUSION: Patients with mandibular third molars have an increased risk of angle fractures. The risk for an angle fracture varied depending on the third molar position.
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Fraturas Mandibulares , Dente Impactado , Humanos , Mandíbula/diagnóstico por imagem , Fraturas Mandibulares/diagnóstico por imagem , Fraturas Mandibulares/epidemiologia , Dente Serotino/diagnóstico por imagem , Estudos Retrospectivos , Fatores de Risco , Dente Impactado/diagnóstico por imagemRESUMO
Allenyl sulfones are versatile building blocks that readily partake in a variety of transformations such as Michael additions, rearrangements, cycloadditions, electrophilic additions and redox reactions. Selected recent developments in the preparation and various reactions of allenyl sulfones are presented.
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Indoles, benzofurans and benzosultams endowed with arylsulfonyl groups were prepared in two steps from 2-bromoallyl sulfones. ortho-Halosulfonamides and ortho-iodophenol reacted with 2-bromoallyl sulfones in the presence of cesium carbonate to furnish products resulting from a formal vinylic substitution reaction. Palladium-catalyzed intramolecular Heck reaction of these adducts furnished sulfonylated indoles, benzosultams and benzofurans. Isomerization of the double bond participating in the Heck reaction under basic conditions led to the formation of two isomeric products in two cases. Conditions for selectively accessing each of the regioisomeric indoles were developed.
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A facile DBU-mediated [3 + 3] benzannulation reaction of 1,3-bis-sulfonyl propenes and Morita-Baylis-Hillman (MBH) bromides is described. The benzannulation reaction afforded bis-sulfonyl biarylmethanes/arenes with complete regioselectivity. The products may be converted readily into corresponding benzophenones via site-selective benzylic oxidation.
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In the fusion fuel cycle, the accurate analysis and understanding of the chemical composition of any gas mixture is of great importance for the efficient design of a tritium extraction and purification system or any tritium handling system. Methods like laser Raman spectroscopy and gas chromatography with thermal conductivity detector have been considered for hydrogen isotopes analyses in fuel cycles. Gas chromatography with a cryogenic separation column has been used for the analysis of hydrogen isotopes gas mixtures in general due to its high reliability and ease of operation. Hydrogen isotopes gas mixture analysis with cryogenic columns has been reported earlier using different column materials for percentage level composition. In the present work, trace levels of hydrogen isotopes (â¼100 ppm of H2 and D2 ) have been analyzed with a Zeolite 5A and a modified γ-Al2 O3 column. Impurities in He gas (â¼10 ppm of H2 , O2 , and N2 ) have been analyzed using a Zeolite 13-X column. Gas chromatography with discharge ionization detection has been utilized for this purpose. The results of these experiments suggest that the columns developed were able to separate ppm levels of the desired components with a small response time (<6 min) and good resolution in both cases.
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BACKGROUND: Depression is the most common form of mental disorder among inmates, with a prevalence much higher than in the general population. This study aims to estimate the prevalence of depression among inmates and identify factors associated with it. METHODS: This cross-sectional study was conducted in Jhumka Regional Prison, the largest prison in eastern Nepal, from September 2014 to August 2015. A total of 434 randomly selected inmates were interviewed using a semi-structured questionnaire examining socio-demographic characteristics, detention status, self-reported health problems, substance use status, and suicidal ideation. Depression was screened using the Center for Epidemiologic Studies Depression scale. Chi-square tests and multiple logistic regression analysis were applied to determine the association between depression and related variables. RESULTS: The mean age of the participants was 35.7 years (SD 13.3). The prevalence of depression among the inmates was 35.3%. Approximately 2.3% reported suicidal ideation during imprisonment and 0.9% had attempted suicide inside the prison. In bivariate analysis, depression was significantly associated with previous incarceration (OR = 1.91, 95% CI = 1.05-3.47, p = 0.033), poor self-rated health (OR = 1.75, 95% CI = 1.16-2.64, p = 0.007), frequent appointments when encountering health problems (OR = 1.66, 95% CI = 1.06-2.61, p = 0.028), suicidal ideation (OR = 4.44, 95%CI = 1.13-17.44, p = 0.038) and loss of weight (OR = 1.49, 95% CI = 1.00-2.23, p = 0.049). However, only previous incarceration (AOR = 1.97, 95% CI = 1.04-3.74, p = 0.037) and frequent appointments when encountering health problems (AOR = 1.61, 95% CI = 1.01-2.57, p = 0.046) remained significant in a multivariate model. CONCLUSIONS: This study showed a high rate of depression among inmates in Nepal. The results suggest a need for psychiatric and rehabilitative care in correctional settings to improve the health status of the inmates.
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Depressão/epidemiologia , Transtorno Depressivo/epidemiologia , Saúde Mental/estatística & dados numéricos , Prisioneiros/psicologia , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nepal , Prevalência , Prisioneiros/estatística & dados numéricos , Prisões , Ideação Suicida , Tentativa de Suicídio/psicologia , Inquéritos e QuestionáriosRESUMO
Monodisperse silver (Ag) nanoparticles were synthesized by using Parthenium hystrophorus L leaf extract in aqueous media. The synthesized nanoparticles were characterized by using UV-vis spectrophotometer, X-ray diffracto-meter (XRD), transmission electron microscope (TEM), and dynamics light scattering (DLS). Size-dependent antibacterial activities of Ag nanoparticles were tested against Gram negative Pseudomonas aeruginosa and Gram positive Staphylococcus aureus. Ag nanoparticles having 20 ± 2 nm size in diameter show maximum zone of inhibition (23 ± 2.2 mm) in comparison to 40 nm and 70 nm diameter nanoparticles for Pseudomonas aeruginosa. The zone of inhibition against Staphylococcus aureus were 19 ± 1.8 mm, 15 ± 1.5 mm and 11 ± 1 mm for 20 nm, 40 nm, and 70 nm, respectively. In addition, affect of concentration of 20 nm size Ag nanoparticles on Bacillus cereus, Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus species were also reported and results were compared with 10 µg/ml dose of Gentamicin sulphate. The Parthenium hystrophorus L leaf extract capped 20 ± 2 nm Ag nanoparticles (7.5 µg/ml) shows statistically significant antibacterial activity than Gentamicin sulphate (10 µg/ml) against Staphylococcus aureus.
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Antibacterianos/síntese química , Antibacterianos/farmacologia , Gentamicinas/farmacologia , Nanopartículas Metálicas/administração & dosagem , Extratos Vegetais/farmacologia , Prata/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Macrófagos/efeitos dos fármacos , Macrófagos/fisiologia , Camundongos , Partenogênese , Folhas de Planta , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Água/farmacologiaRESUMO
In the present study, singlet oxygen (¹O2) scavenging activity of tocopherol and plastochromanol was examined in tocopherol cyclase-deficient mutant (vte1) of Arabidopsis thaliana lacking both tocopherol and plastochromanol. It is demonstrated here that suppression of tocopherol and plastochromanol synthesis in chloroplasts isolated from vte1 Arabidopsis plants enhanced ¹O2 formation under high light illumination as monitored by electron paramagnetic resonance spin-trapping spectroscopy. The exposure of vte1 Arabidopsis plants to high light resulted in the formation of secondary lipid peroxidation product malondialdehyde as determined by high-pressure liquid chromatography. Furthermore, it is shown here that the imaging of ultra-weak photon emission known to reflect oxidation of lipids was unambiguously higher in vte1 Arabidopsis plants. Our results indicate that tocopherol and plastochromanol act as efficient ¹O2 scavengers and protect effectively lipids against photooxidative damage in Arabidopsis plants.