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1.
Org Lett ; 25(7): 1172-1177, 2023 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-36779869

RESUMEN

Chiral benzoxazinones and 4H-3,1-benzoxazines as important motifs are widely found in abundant pharmaceuticals and biological molecules. We herein successfully developed the first kinetic resolution (KR) process of racemic benzoxazinones through Ir-catalyzed asymmetric intramolecular allylation, furnishing a wide range of chiral benzoxazinones and 4H-3,1-benzoxazines with excellent results via outstanding KR performances (with the s factor up to 170). This protocol exhibited broad substrate scope generality and good functional group tolerance, and the chiral 4H-3,1-benzoxazine products could be readily transformed to other useful optically active heterocycles.

2.
Comput Math Methods Med ; 2022: 1956908, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36254239

RESUMEN

Background: Despite guidelines provided by the Brain Trauma Foundation (BTF) for treating patients with TBI, including advice to monitor intracranial pressure (ICP), the clinical application of ICP monitoring is far from universal. This laxity has been attributed to the relationship between mortality in TBI patients and ICP monitoring. Objective: This systematic review and meta-analysis was aimed at determining the effect of intracranial pressure (ICP) monitoring on the mortality of patients with traumatic brain injury (TBI). Method: A systematic search for articles was conducted on PubMed, Scopus, Cochrane Central Register of Control Trials (CENTRAL), and APA PsycNet for articles published from 1 January 2000 to 1 August 2022. Manager 5.4 was used to carry out statistical analysis. Results: Article search yielded 1421 articles, but only 23 cohort studies were included in the systematic review and meta-analysis. The total number of study participants is 80,058. Seventeen studies reported unadjusted odds ratios (OR), and only 8 reported the adjusted odds ratio (OR). Nine out of seventeen studies reported an unadjusted OR of less than 1, and five out of eight studies reported an adjusted OR of less than 1. From this paper's analysis, the OR for in-hospital mortality was 1.01 [95% CI, 0.80, 1.28], with a p value of 0.92. OR for ICU mortality was 0.84 [95% CI, 0.52, 1.35], with a p value of 0.47. Conclusion: But due to conflicting results, as evident above, it is unsatisfyingly challenging to draw any substantial conclusions from them. This paper thus calls for more research on this particular paper.


Asunto(s)
Lesiones Traumáticas del Encéfalo , Presión Intracraneal , Estudios de Cohortes , Mortalidad Hospitalaria , Humanos , Monitoreo Fisiológico/métodos
3.
Comput Intell Neurosci ; 2022: 6002672, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36275975

RESUMEN

Background: The first-line treatment for patients with any type of pituitary adenoma is trans-sphenoidal surgery. Considering the prevalence of the condition globally, the treatment is quite common. The recurrence of pituitary adenoma is a recognized occurrence in the medical field; however, there is limited comprehensive research and analysis of the predictive factors of recurrence rates and the clinical factors impacting relapse rates. Identifying the recurrence rates of pituitary adenomas and the clinical factors associated with them could help increase the remission rate by increasing focus on the specific aspects for early diagnosis and improved treatment. Objective: The objective of the current systematic review and meta-analysis is to assess the recurrent rates based on previous studies and to explore the clinical factors after pituitary surgery. Methods: A search was performed on PubMed, APA PsycINFO, Scopus, CENTRAL, and Google Scholar databases for English articles published from 1st January 2010 to 1st August 2022. Systematic reviews, meta-analysis, evidence syntheses, editorials, commentaries, preclinical studies, abstracts, theses, and preprints were excluded. Meta XL statistical software was used to conduct a prevalence meta-analysis. Results: PubMed, PsycINFO, and Medline databases were searched. All of the articles were written between 2012 and 2022. In the beginning, 612 items were recognized. After removing duplicates and analyzing the remaining articles in terms of inclusion and exclusion criteria, 31 articles remained. Conclusion: There is a relationship between recurrence rates and the follow-up period. There were conflicting results about the clinical factors after pituitary adenoma surgery, specifically age and tumor size. Some included studies that there was an association between macroadenomas and high recurrence rates. No study reported that gender was a clinical factor affecting pituitary adenoma surgery outcomes or the recurrence rate. Studies also reported that there was a correlation between the remnant tumor factor and the recurrence rates; adenoma remnants after surgery increased the risk of recurrence rates for patients.


Asunto(s)
Adenoma , Neoplasias Hipofisarias , Humanos , Neoplasias Hipofisarias/epidemiología , Neoplasias Hipofisarias/cirugía , Neoplasias Hipofisarias/patología , Inteligencia Artificial , Adenoma/epidemiología , Adenoma/cirugía , Adenoma/patología , Computadores
4.
Front Microbiol ; 13: 794738, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35359724

RESUMEN

Wool keratin is difficult to degrade as comparing to feathers because of its tough secondary structure. In order to develop an approach for high-value utilization of wool fiber waste by keratinolytic microorganisms, which is produced from shearing, weaving, and industrial processing of wool, screening of wool-degrading bacterium with high degradation efficiency were performed in this study. To this end, Lysobacter brunescens YQ20 was identified and characterized. The optimized conditions for wool degradation were pH 9.0 and 37°C with 20% liquid volume of Erlenmeyer flask. After fermentation, 15 essential amino acids were detected when wool fiber waste was fermented. The total amino acids produced from 1% wool per hour were 13.7 mg/L. The concentration was 8.6-fold higher than that produced by the strain Stenotrophomonas maltophilia BBE11-1, which had previously been reported to have the highest wool-degrading capacity. Our study reports the first Lysobacter strain that exhibits efficient wool degradation and yields higher concentrations of amino acids than previously reported strains. Whole-genome sequencing indicated that there were 18 keratinase-like genes in the genome of YQ20, which exhibited a long evolutionary distance from those of Bacillus. Therefore, L. brunescens YQ20 may have applications in the environmentally friendly management of wool waste as fertilizer in agriculture.

5.
Environ Microbiol ; 23(9): 5481-5486, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34309156

RESUMEN

Atmospheric particulate matter (APM) is an environmental hazard that endangers human health and causes a variety of diseases. In this work, the microbial community composition, chemical element composition and antimicrobial resistance gene (ARG) prevalence, along with their relationships with environmental parameters were analysed using APM samples collected in Jinan, China. Pathogenic Klebsiella and Aeromonas were found to be significantly correlated with PM2.5 and temperature, suggesting their proliferation on APM. PM2.5 and PM10 have similar microbial community compositions but different chemical element compositions, suggesting they have different origins, which have little impact on microbial community structures. This finding, together with analysis of the timing of microbial community structure changes, suggests that microbial community composition is impacted by anthropic activities. Further investigations showed that rare metals including lanthanides are significantly negatively correlated with pathogens in APM, suggesting their inhibitory role. ARGs were observed for every class of antibiotic except for carbapenems in APM, suggesting high ARG prevalence in APM, and APM functions in transmission of antimicrobial resistance. Results obtained in this study suggest that APM can act as a transmission vehicle for pathogenic bacteria and ARGs and lead to the implication of a new transmission route for bacterial pathogenesis by APM.


Asunto(s)
Microbiología del Aire , Microbiota , Material Particulado , Bacterias/genética , Monitoreo del Ambiente , Genes Bacterianos , Metales/análisis , Material Particulado/análisis
6.
Chem Commun (Camb) ; 56(36): 4934-4937, 2020 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-32239044

RESUMEN

Highly efficient Ni-catalyzed asymmetric hydrogenation of cyclic N-sulfonyl ketimino esters was, for the first time, successfully developed, providing various chiral α-monosubstituted α-amino acid derivatives with excellent results (97-99% yields, 90 to >99% ee). Cyclic N-sulfonyl ketimines were also hydrogenated well to afford chiral amine derivatives with 98-99% yields and 97 to >99% ee. The gram-scale asymmetric hydrogenation was performed well with 85% yield and 99% ee using only 0.2 mol% catalyst.

7.
Org Lett ; 21(11): 3923-3926, 2019 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-31117697

RESUMEN

The highly efficient Ni-catalyzed asymmetric hydrogenation of ß-boronic ester substituted-α,ß-unsaturated carboxylic esters was successfully developed using ( S, S)-Ph-BPE as the ligand. A series of chiral ß-borylated carboxylic esters were obtained with high yields (94%-99% yields) and excellent enantioselectivities (89%-99% ee). The gram-scale asymmetric hydrogenation with a low catalyst loading (0.25 mol %) and synthetic transformation of hydrogenation product demonstrated the great synthetic utility of this methodology.

8.
RSC Adv ; 9(33): 18971-18977, 2019 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-35516889

RESUMEN

Benzoic acid (BA) is one of the most common organic acids in the Earth's atmosphere and an important component of atmospheric aerosol particles. The reaction mechanism of OH, NO3 and SO4 - radicals with BA in atmospheric water droplets and that of OH radicals with BA in the atmosphere were studied in this paper. The results show that in atmospheric water droplets the potential barriers of the elementary addition reactions of BA with OH radicals are lower than those of elementary abstraction reactions, and the potential barriers of OH-initiated reactions are less than for NO3 and SO4 - reactions. The initiation reactions of OH radicals and BA are exothermic, but the abstraction reactions of NO3 and SO4 - are endothermic processes. Among the products, 6-hydroxybenzoic acid (6-HBA) and 4,6-dihydroxybenzoic acid (4,6-DHBA) are the most stable, while 3-hydroxybenzoic acid (3-HBA) and 3,5-dihydroxybenzoic acid (3,5-DHBA) are much less stable and, thus, much less abundant compared to 6-HBA and 4,6-DHBA. The initiation and subsequent degradation of BA with OH radicals in the gas phase were calculated. The products of addition and abstraction reactions of BA with OH radicals can be further oxidized and degraded by O2/NO. According to the results of kinetic calculations, the total reaction rate constant of OH radicals with BA at 298.15 K in atmospheric water droplets is 2.35 × 10-11 cm3 per molecule per s. The relationship between reaction rate constants, temperature and altitude were also investigated and discussed in the present study.

9.
Sci Total Environ ; 627: 256-263, 2018 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-29426148

RESUMEN

Hexachloro-1,3-butadiene (HCBD) is a persistent organic pollutant in the environment. When its samples were collected and observed, the levels of HCBD in its source and high mountains are higher than in urban cities, oil factories and countryside. The density functional theory is applied to the degradation mechanism of HCBD with Cl, NO3, HO2, OH and O3. Those reactions are optimized and calculated at two carbon sites of double bonds, and then the subsequent reactions of the OH-initiated intermediates with O2 and NO are taken as examples. Ozonization reactions of HCBD including the formation of primary and secondary ozonides are investigated. The Criegee intermediates created in the ozonization reactions can react with O2, SO2, NO2 and H2O. Reaction rate constants of the Cl, NO3, HO2, OH and O3 initiated reactions with HCBD are calculated within 200 to 400 K with the transition state theory method, and the rate constants of the Cl, NO3, HO2, OH and O3 at 298.15 K are 4.51 × 10-13, 1.32 × 10-20, 4.33 × 10-29, 6.33 × 10-16, 5.80 × 10-27 cm3 molecule-1 s-1, respectively. The reactions of OH and Cl radicals with HCBD are more important than those of NO3, HO2 and O3 according to the reaction rate branching ratio. Both the temperature and reaction rate could change with the height.

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