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2.
Artículo en Inglés | MEDLINE | ID: mdl-38703313

RESUMEN

Population growth and environmental degradation are major concerns for sustainable development worldwide. Hydrogen is a clean and eco-friendly alternative to fossil fuels, with a heating value almost three times higher than other fossil fuels. It also has a clean production process, which helps to reduce the emission of hazardous pollutants and save the environment. Among the various production methodologies described in this review, biochemical production of hydrogen is considered more suitable as it uses waste organic matter instead of fossil fuels. This technology not only produces clean energy but also helps to manage waste more efficiently. However, the production of hydrogen obtained from this method is currently more expensive due to its early stage of development. Nevertheless, various research projects are underway to develop this method on a commercial scale.

3.
Health Policy Plan ; 38(8): 907-915, 2023 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-37494416

RESUMEN

Smokeless tobacco (SLT) consumption increases the risk of cardiovascular diseases and cancer and leads to adverse reproductive health outcomes among women and newborns. This study examines the factors associated with initiation, continuation and cessation of SLT use among women in the reproductive age so as to formulate and include prevention and cessation interventions from its inception. The study was conducted in urban low-income communities in India. Using snowball and purposive sampling techniques, in-depth interviews were conducted with 20 pregnant and 22 lactating women who currently used SLT products. Data were analysed using thematic analysis with the help of QSR NVivo software. Findings revealed that factors such as people influencing usage change with different life stages including pre-marital and post-marital periods. Perceived health benefits, altered taste preferences during pregnancy and social influences were also studied. Women were found to be more aware of the harmful effects of tobacco during pregnancy than during breastfeeding. Social stigma around women consuming tobacco acted as a major driving factor for cessation. Most of the participants were willing to quit but were not aware of any technique or programme for cessation. The findings of the study highlight the need to develop behavioural change intervention tools, which are culturally and locally appropriate and have a gender-sensitive approach. Different socio-cultural factors associated with initiation/cessation at different life stages should also be taken into consideration while developing these tools.


Asunto(s)
Tabaquismo , Tabaco sin Humo , Recién Nacido , Embarazo , Humanos , Femenino , Tabaco sin Humo/efectos adversos , Lactancia , Uso de Tabaco , India
4.
Extremophiles ; 27(1): 1, 2022 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-36456889

RESUMEN

Archaea and bacteria in geothermal environments are predicted to suffer DNA depurination in vivo at high rates, which raises questions regarding the biological roles of their abasic-site-repair enzymes. Gene deletion and enzymatic assay demonstrated that the saci_0015 gene of Sulfolobus acidocaldarius encodes an AP endonuclease (Apn) accounting for as much as 95% of the assayable activity in cell extracts and is not essential for viability. To identify genetic functions of this enzyme, deletion (ΔApn) strains were examined with respect to growth, spontaneous mutation, transformation by ssDNA containing an abasic site, and conjugation. Relative to its isogenic control, the ΔApn strain did not exhibit any change in growth rate or final cell density, rate or spectrum of spontaneous mutation, transformation by DNA containing an abasic site, or efficiency of DNA transfer and recombination. The apparent lack of genetic impact of removing the major AP endonuclease was unexpected and indicated that abasic sites are rarely bypassed directly by DNA polymerases in S. acidocaldarius. AP endonuclease deficiency had no obvious effect on survival of S. acidocaldarius under several test conditions, but it accelerated the death of cells at 4º C under illumination. Our results suggest that the normal level of AP endonuclease in S. acidocaldarius is well above the minimum required for growth and cell division but not for recovery from prolonged exposure to certain low-temperature conditions. This situation illustrates a biological challenge that has not been emphasized in experimental studies of extremophiles, i.e., the problem of long-term survival under "non-extreme" conditions.


Asunto(s)
Archaea , Extremófilos , Endonucleasas , ADN-(Sitio Apurínico o Apirimidínico) Liasa , División Celular
5.
Front Public Health ; 10: 999552, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36311609

RESUMEN

Smokeless tobacco (SLT) consumption is associated with multiple adverse health effects and mortality, with the highest burden in India. The WHO FCTC has banned tobacco advertisement, promotion and sponsorship via Article 13. Indian laws also prohibit any kind of direct or indirect advertisements in all forms of audio, visual, and print media; brand promotion; and sponsorship of tobacco products. However, the tobacco industry continues to find aggressive marketing ways to advertise their products. This study aims to assess the extent of surrogate advertisement of smokeless tobacco products through frequency modulation (FM) radio stations in the city of Delhi (National Capital Territory of India). In this study, the advertisements broadcasted over FM radio across different channels (private and government owned) in total 162 h were analyzed. The time duration was spread evenly over morning peak hours, off hours, and evening peak hours. It was found that multiple brands including Vimal, Kamla Pasand, and Rajshree have used surrogate advertising to market their brands that are commonly associated with smokeless tobacco products. However, no such advertisement was found to be aired on government-owned FM channels. The total surrogate advertisements broadcasted were over 286 times, where no significant difference was found in distribution among peak and non-peak hours. The study indicated that the tobacco industry is making its way to sell the products through indirect advertisements. The need of the hour is to not only enforce tobacco advertising ban laws in all forms of advertising media but also to strictly regulate smokeless tobacco products.


Asunto(s)
Industria del Tabaco , Productos de Tabaco , Tabaco sin Humo , Tabaco sin Humo/efectos adversos , Uso de Tabaco , Publicidad , Nicotiana
6.
J Bacteriol ; 2020 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-32482723

RESUMEN

To identify DNA-oxidation defenses of hyperthermophilic archaea, we deleted genes encoding the putative 7,8-dihydro-8-oxoguanine (oxoG)-targeted N-glycosylase of S. acidocaldarius (ogg; Saci_01367), the Y-family DNA polymerase (dbh; Saci_0554), or both, and measured the effects on cellular survival, replication accuracy, and oxoG bypass in vivo Spontaneous G:C to T:A transversions were elevated in all Δogg and Δdbh constructs, and the Δogg Δdbh double mutant lost viability at a faster rate than isogenic WT and ogg strains. The distribution of G:C to T:A transversions within mutation-detector genes suggested that reactivity of G toward oxidation and the effect on translation contribute heavily to the pattern of mutations that are recovered. An impact of the Ogg protein on overall efficiency of bypassing oxoG in transforming DNA was evident only in the absence of Dbh, and Ogg status did not affect the accuracy of bypass. Dbh function, in contrast, dramatically influenced both the efficiency and accuracy of oxoG bypass. Thus, Ogg and Dbh were found to work independently to avoid mutagenesis by oxoG, and inactivating this simple but effective defense system by deleting both genes imposed a severe mutational burden on S. acidocaldarius cells.IMPORTANCE Hyperthermophilic archaea are expected to have effective (and perhaps atypical) mechanisms to limit the genetic consequences of DNA damage, but few gene products have been demonstrated to have genome-preserving functions in vivo This study confirmed by genetic criteria that the S. acidocaldarius Ogg protein avoids the characteristic mutagenesis of G oxidation. This enzyme and the bypass polymerase Dbh have similar impacts on genome stability but work independently, and may comprise most of the DNA-oxidation defense of S. acidocaldarius The critical dependence of accurate oxoG bypass on the accessory DNA polymerase Dbh further argues that some form of polymerase exchange is important for accurate genome replication in Sulfolobus, and perhaps in related hyperthermophilic archaea.

7.
Front Microbiol ; 11: 613375, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33424816

RESUMEN

The thermophilic crenarchaeon Sulfolobus acidocaldarius has four DNA polymerases (DNAPs): PolB1, PolB2, PolB3, and Dbh (PolY). Previous in vitro studies suggested that PolB1 is the main replicative DNAP of Sulfolobales whereas PolB2 and Y-family polymerases Dpo4 (Saccharolobus solfataricus) or Dbh are involved in DNA repair and translesion DNA synthesis. On the other hand, there are various opinions about the role of PolB3, which remains to be clearly resolved. In order to examine the roles of the DNAPs of S. acidocaldarius through in vivo experiments, we constructed polB2, polB3, and dbh deletion strains and characterized their phenotypes. Efforts to construct a polB1 deletion strain were not successful; in contrast, it was possible to isolate triple gene-deletion strains lacking polB2, polB3, and dbh. The growth of these strains was nearly the same as that of the parent strains under normal growth conditions. The polB2, polB3, and dbh single-deletion strains were sensitive to some types of DNA-damaging treatments, but exhibited normal sensitivity to UV irradiation and several other damaging treatments. Overall, the genotype which exhibited the greatest sensitivity to the DNA-damaging treatments we tested was the ΔpolB2 ΔpolB3 combination, providing the first evidence of overlapping function for these two DNAPs in vivo. The results of our study strongly suggest that PolB1 is responsible for the DNA replication of both the leading and lagging strands and is sufficient to complete the repair of most DNA damage under normal growth conditions in S. acidocaldarius.

8.
Emerg Med Clin North Am ; 36(4): 711-722, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30297000

RESUMEN

Central nervous system (CNS) infections require early recognition and aggressive management to improve patient survival and prevent long-term neurologic sequelae. Although early detection and treatment are important in many infectious syndromes, CNS infections pose unique diagnostic and therapeutic challenges. The nonspecific signs and symptoms at presentation, lack of characteristic infectious changes in laboratory and imaging diagnostics, and closed anatomic and immunologically sequestered space each present challenges to the emergency physician. This article proposes an approach to the clinical evaluation of patients with suspected CNS infection and highlights methods of diagnosis, treatment, and complications associated with CNS infections.


Asunto(s)
Infecciones del Sistema Nervioso Central/diagnóstico , Diagnóstico por Imagen/métodos , Diagnóstico Precoz , Servicio de Urgencia en Hospital/organización & administración , Humanos
9.
J Neuroinflammation ; 12: 210, 2015 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-26581714

RESUMEN

BACKGROUND: In experimental autoimmune encephalomyelitis (EAE), deletion of transient receptor potential melastatin 4 (Trpm4) and administration of glibenclamide were found to ameliorate disease progression, prompting speculation that glibenclamide acts by directly inhibiting Trpm4. We hypothesized that in EAE, Trpm4 upregulation is accompanied by upregulation of sulfonylurea receptor 1 (Sur1) to form Sur1-Trpm4 channels, which are highly sensitive to glibenclamide, and that Sur1-Trpm4 channels are required for EAE progression. METHODS: EAE was induced in wild-type (WT) and Abcc8-/- mice using myelin oligodendrocyte glycoprotein 35-55 (MOG35-55). Lumbar spinal cords were examined by immunohistochemistry, immuno-Förster resonance energy transfer (immunoFRET), and co-immunoprecipitation for Sur1-Trpm4. WT/EAE mice were administered with the Sur1 inhibitor, glibenclamide, beginning on post-induction day 10. Mice were evaluated for clinical function, inflammatory cells and cytokines, axonal preservation, and white matter damage. RESULTS: Sur1-Trpm4 channels were upregulated in EAE, predominantly in astrocytes. The clinical course and severity of EAE were significantly ameliorated in glibenclamide-treated WT/EAE and in Abcc8-/-/EAE mice. At 30 days, the lumbar spinal cords of glibenclamide-treated WT/EAE and Abcc8-/-/EAE mice showed significantly fewer invading immune cells, including leukocytes (CD45), T cells (CD3), B cells (CD20) and macrophages/microglia (CD11b), and fewer cells expressing pro-inflammatory cytokines (TNF-α, IFN-γ, IL-17). In both glibenclamide-treated WT/EAE and Abcc8-/-/EAE mice, the reduced inflammatory burden correlated with better preservation of myelin, better preservation of axons, and more numerous mature and precursor oligodendrocytes. CONCLUSIONS: Sur-Trpm4 channels are newly upregulated in EAE and may represent a novel target for disease-modifying therapy in multiple sclerosis.


Asunto(s)
Encefalomielitis Autoinmune Experimental/tratamiento farmacológico , Receptores de Sulfonilureas/antagonistas & inhibidores , Canales Catiónicos TRPM/antagonistas & inhibidores , Animales , Axones/patología , Femenino , Silenciador del Gen , Gliburida/uso terapéutico , Hipoglucemiantes/uso terapéutico , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Vaina de Mielina/efectos de los fármacos , Glicoproteína Mielina-Oligodendrócito , Fármacos Neuroprotectores/uso terapéutico , Fragmentos de Péptidos , Médula Espinal/patología , Receptores de Sulfonilureas/genética
10.
J Org Chem ; 74(11): 4017-23, 2009 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-19435298

RESUMEN

The purpose of this paper is to convince practitioners of (1)H NMR spectroscopy to consider simple quantum chemical calculations as a viable option to aid them in the assignment of their spectra. To this end, it is demonstrated, on a test set of 80 conformationally stable molecules of various kinds carrying different functional groups, that, in contrast to what is claimed in the literature, large basis sets are not needed to obtain rather accurate predictions of (1)H NMR chemical shifts by quantum chemical calculations. On the other hand, modeling the solvent by an SCRF-type calculation may improve certain predictions significantly. The best accuracy/cost ratio is provided by GIAO calculations in chloroform as a solvent with the specially parametrized WP04 functional of Cramer et al. using the cc-pVDZ or 6-31G** basis set, closely followed by similar calculations with the ubiquitious B3LYP functional (both predict (1)H chemical shifts with an average deviation of ca. 0.12 ppm, if the results are scaled linearly). A slightly higher accuracy can be attained by adding diffuse functions to the basis set, but going to the triple-zeta basis sets which have invariably been used hitherto in calculations of chemical shifts does not lead to any improvement. The popular increment schemes such as those implemented in the ChemDraw or ACD programs do not do nearly as well and are often incapable of correctly distinguishing stereoisomers.


Asunto(s)
Espectroscopía de Resonancia Magnética/métodos , Modelos Moleculares , Compuestos Orgánicos/química , Modelos Químicos , Conformación Molecular , Protones
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