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1.
China CDC Wkly ; 6(27): 651-657, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-39027633

RESUMEN

What is already known about this topic?: Given the common modes of transmission, outbreaks of both human immunodeficiency virus (HIV) and syphilis are primarily observed in men who have sex with men (MSM). However, minimal research has been conducted to concurrently evaluate the rates and trends of HIV and syphilis incidence within this community in China. What is added by this report?: This manuscript presents the incidence rates and associated factors of HIV and syphilis in MSM in Tianjin based on data derived from a decade-long cohort study. Intriguingly, it depicts a decreasing trend in HIV incidence juxtaposed with an increasing incidence of syphilis among this population in Tianjin. What are the implications for public health practice?: The interconnected risk factors for HIV and syphilis pose significant hindrances to disease control. Our study underscores the urgent need for improved intervention strategies specifically aimed at MSM to mitigate the propagation of both infections.

2.
J Org Chem ; 89(10): 7065-7075, 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38666304

RESUMEN

There are several challenging problems such as the usage of combustible and hazardous hydrogen sources and severe environmental pollution in the conventional reduction of aldehydes/ketones to alcohols. We report here a practical, safe, and green electrochemical reduction, which solves these problems to a large extent. Through an undivided cell, Zn(+) and Sn(-) as the electrode, tetrabutylammonium chloride (TBAC) as the electrolyte, water as the solvent and hydrogen source, a wide range of aldehydes and ketones are converted into the corresponding alcohols in mild conditions. Furthermore, the electrolytes and water can be recycled, and reductive deuteration can be achieved by simply using D2O as the solvent. Finally, the reduction can be smoothly scaled up to a kilogram level.

3.
Org Lett ; 26(15): 3069-3074, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38557118

RESUMEN

Free radical three-component nitration/spirocyclization of unsaturated sulfonamides/amides with tert-butyl nitrite was developed for the construction of diverse NO2-revised 4-azaspiro[4.5]decanes. This tandem system featured metal-free participation, simple operation, good selectivity/yields, and a green/low-cost O source. Meanwhile, one nitro-containing complex molecule and a scaled-up operation were performed well to test the synthetic potential of the cascade reaction. Isotopic labeling, radical inhibition experiments, and DFT analysis were carried out to gain insight into the reaction process.

4.
Chem Commun (Camb) ; 60(29): 3938-3941, 2024 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-38497681

RESUMEN

Free radical initiated bicyclization of 1,6-enynes with chloralkanes, is achieved via selective activation of the C(sp3)-H bond of the chloralkane, resulting in diverse polychlorinated/chlorinated polyheterocycles. Two kinds of transformations and a scaled-up experiment were performed to test the synthetic importance of the organic chlorides. Finally, a range of radical inhibition operations and radical clock tests were explored to support the reaction process.

5.
China CDC Wkly ; 5(48): 1067-1072, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-38058987

RESUMEN

What is already known about this topic?: Acquired immunodeficiency syndrome (AIDS) represents a significant public health challenge globally, not only inflicting harm on the health of individuals but also placing a considerable economic strain on society. What is added by this report?: This study represents the inaugural report on the potential reduction in economic burden attributable to human immunodeficiency virus (HIV) prevention strategies in Tianjin. Between 2011 and 2022, it is estimated that effective measures could prevent 2,965 new HIV infections and avert 658 deaths, resulting in an economic benefit of approximately 14.437 billion Chinese Yuan. What are the implications for public health practice?: The findings of this study offer valuable evidence to inform the development of localized HIV prevention and control strategies, as well as to guide public health policymaking.

6.
Chem Commun (Camb) ; 59(89): 13352-13354, 2023 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-37872833

RESUMEN

We demonstrated herein an I2O5-mediated radical nitration of olefins with NaNO2. A variety of (E)-nitroolefins can be synthesized in high yields and chemoselectivity.

7.
J Org Chem ; 88(16): 12141-12149, 2023 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-37530034

RESUMEN

A cyanomethylation/cyclization of aryl acetylenes/ethylenes with bromoacetonitrile was finished in a photopromoted condition, which offers an efficient and mild protocol for the preparation of cyanomethylated 7- or 5-membered N-heterocycles with good yields. Meanwhile, trichloroacetonitrile was also compatible with this radical pathway. In addition, a variety of single-crystal X-ray diffraction measurements, scaled-up operations to 1 mmol, functional group transformations of final products, light on/off experiments, and even radial inhibition studies were smoothly performed in this tandem system.

8.
J Org Chem ; 88(7): 4854-4862, 2023 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-36947717

RESUMEN

A metal/peroxide-free involved simple cascade 6-exo-trig spirocyclization of tert-butyl nitrite with biaryl ynones has been finished, which resulted in various NO2-modified spiro[5,5]trienones with good regioselectivity/yields. A variety of scaled-up experiments, reduction/epoxidation operations, and mechanistic studies were performed to verify the merits and spirocyclization process of this radical system. Finally, the structure of the spirocycles was confirmed by single-crystal X-ray diffraction.

9.
Artículo en Inglés | MEDLINE | ID: mdl-36674198

RESUMEN

COVID-19 accelerated the growth of the digital economy and digital transformation across the globe. Meanwhile, it also created a higher demand for productivity in the real economy. Hence, the correlation between the digital economy and green productivity is worth studying as COVID-19 prevention becomes the norm. The digital economy overcomes the limitations imposed by traditional factors of production on economic growth and empowers innovative R&D and resource allocation in all aspects. This study delved into the digital economy by focusing on its green value at different levels of development. The study gathered the green-productivity indices and the principal components of the digital economy for each prefecture-level city in China from 2011 to 2019 and meticulously portrayed their trends in spatial and temporal figures. Meanwhile, regression models were used to verify the mechanism through which digital-economy development influences the changes in green productivity. The results showed that: (1) a higher level of digital economy helps to increase urban green total-factor productivity (GTFP) and that the conclusions of this paper still held after potential endogeneity problems were solved through the instrumental-variables approach; (2) the digital economy will drive an increase in urban GTFP by upgrading firms' production technologies and that digital-economy development encourages green patent applications from firms; and (3) as the digital economy develops, it will also drive urban GTFP increases by removing polluting enterprises from the market and that the higher the level of digital-economy development, the greater the number and probability of polluting enterprises exiting the market. In view of this study's results, the government should increase the importance of the digital economy, strengthen the role of the digital economy in promoting urban green development, and provide more guidance on regional green development with the help of the digital economy.


Asunto(s)
COVID-19 , Humanos , Ciudades , COVID-19/epidemiología , Desarrollo Económico , Asignación de Recursos , China , Eficiencia
10.
Org Biomol Chem ; 21(1): 75-79, 2022 12 21.
Artículo en Inglés | MEDLINE | ID: mdl-36448655

RESUMEN

A palladium-catalyzed ß-C(sp3)-H nitrooxylation of aliphatic alcohols with AgNO2 is reported. An 8-formylquinoline-derived oxime is installed as an exo-type directing group for sp3 C-H activation and selectfluor acts as the oxidant. The reaction tolerates a variety of functional groups and shows good selectivity for ß-C-H nitrooxylation of alcohols.


Asunto(s)
Alcoholes , Paladio , Catálisis , Estructura Molecular , Oxidantes
11.
J Org Chem ; 87(13): 8773-8781, 2022 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-35709505

RESUMEN

Persulfate-promoted radical cascade trifluoromethylthiolation of aryl acetylenes with AgSCF3 provides a simple reaction system for the synthesis of SCF3-substituted dibenzazepines or dioxodibenzothiazepines with good Z/E selectivity. The single-crystal X-ray diffraction data confirms the structures of the final products. A series of scaled-up experiments, further transformations, and radical inhibition experiments were operated in the reaction system.


Asunto(s)
Alquinos , Dibenzazepinas , Catálisis , Radicales Libres
12.
Xenobiotica ; 52(5): 520-526, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35723590

RESUMEN

The recommended treatment regimen for tuberculosis is a combination of agents with antitubercular activity, during which hepatotoxicity is one of the most common side effects. In addition to the N-acetyltransferase 2 (NAT2) genotype, rs3814055 in nuclear receptor subfamily 1, group I, member 2 (NR1I2) has been demonstrated to be associated with anti-tuberculosis drug-induced hepatotoxicity (ATDH), but previous results have been inconsistent.A retrospective nested hospital-based case-control study was performed to investigate the association between genetic polymorphisms and the risk of ATDH. Fifteen genetic variants (13 SNPs and two null genotypes) in cytochrome P450 2E1, NR1I2, UDP-glucuronosyltransferase 1A1, NAT2, superoxide dismutase 1, superoxide dismutase 2, and glutathione S-transferases (GSTT1, GSTM1, GSTP1) were genotyped. Odds ratios with 95% confidence intervals were calculated with drug doses, body mass index comorbidity of diabetes mellitus, and baseline alanine transaminase value as covariates.Conditional logistic regression demonstrated that the NAT2 slow acetylation genotype and the T allele of rs3814055 in NR1I2 may contribute to susceptibility to ATDH.Stratified association analysis demonstrated that in NAT2 non-slow acetylators, the T allele of rs3814055 was a risk factor for ATDH, whereas the T allele did not increase the susceptibility to ATDH in slow acetylators.


Asunto(s)
Arilamina N-Acetiltransferasa , Enfermedad Hepática Inducida por Sustancias y Drogas , Antituberculosos , Estudios de Casos y Controles , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Polimorfismo de Nucleótido Simple , Receptor X de Pregnano , Estudios Retrospectivos
13.
Org Biomol Chem ; 20(20): 4074-4080, 2022 05 26.
Artículo en Inglés | MEDLINE | ID: mdl-35535704

RESUMEN

Organoboronic acids act as carbon-centered radical precursors that are widely utilized to construct diverse C-C bonds. This review summarizes the advances in this field. The content is divided into four parts according to the different categories of coupling partners with organoboronic acids. The reaction conditions as well as the mechanisms are demonstrated in each part.


Asunto(s)
Carbono , Alquilación , Carbono/química , Catálisis , Radicales Libres
14.
Int J Antimicrob Agents ; 59(6): 106589, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35405268

RESUMEN

OBJECTIVES: Linezolid can significantly impact drug-resistant tuberculosis (DR-TB) patient outcomes. However, the long-term use of this drug for TB treatment has been limited by adverse reactions and uncertainty regarding optimal dosage regimens for balancing drug efficacy and safety across different populations. This study attempted to find the optimal dosing regimen of linezolid in different populations. METHODS: A total of 355 blood samples were collected from 126 DR-TB patients. Population pharmacokinetic analysis (using a one-compartment model) and dose simulations were conducted using NONMEM and R software. The ratio between the area under the free drug plasma concentration-time curve to the MIC (fAUC/MIC) of > 119 and trough concentration (Cmin) ≤ 2 mg/L served as efficacy and safety targets, respectively, toward the formulation of optimal dosage regimens based on a ≥ 90% cumulative fraction of response. RESULTS: Body weight and blood urea nitrogen levels were the most significant covariates of apparent volume, while creatinine clearance and haemoglobin level significantly influenced apparent clearance. The probability of target attainment for different dosage regimens was evaluated via Monte Carlo simulation. For subjects with MICs of 0.125, 0.25 and 0.5 mg/L, specific total daily doses of ≥ 300 mg, ≥ 450 mg and ≥ 900 mg were required to reach the target, respectively. Subjects with body weight ≤ 70 kg and MIC ≥ 1 mg/L received a total 1200 mg daily dose to reach the probability of target attainment target. Notably, single dosing was safer than multiple dosing at the same daily dose. The optimal dosage regimens for subjects with body weight < 50 kg and ≥ 50 kg were 450 mg/d and 600 mg/d (once daily), respectively. CONCLUSION: Optimal dosage regimens for patients weighing < 50 kg and ≥ 50 kg were 450 mg/d and 600 mg/d, respectively. A single dose was safer than multiple doses.


Asunto(s)
Tuberculosis Resistente a Múltiples Medicamentos , Antibacterianos/uso terapéutico , Peso Corporal , Humanos , Linezolid , Pruebas de Sensibilidad Microbiana , Método de Montecarlo , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológico
15.
Front Microbiol ; 13: 803521, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35250926

RESUMEN

BACKGROUND: Pleural tuberculous is difficult to diagnose. Culture is still considered the gold standard, especially in resource-limited settings where quick, cheap, and easy techniques are needed. The aim of the study was to evaluate resuscitation-promoting factors (Rpfs)-based thin layer agar (TLA) culture method for quick detection of Mycobacterium tuberculosis in pleural fluid. METHODS: Patients with suspected pleural TB were enrolled prospectively in our hospital, pleural fluid of all patients were collected, stained with Ziehl-Neelsen for acid-fast bacilli (AFB), cultured on Rpfs-TLA, TLA, and Löwenstein-Jensen (LJ) medium, and identified according to recommended procedures. RESULTS: A total of 137 suspected pleural TB were enrolled and categorized, including 103 pleural TB (49 confirmed and 54 probable pleural TB) and 34 non-TBP patients. The sensitivity of Rpfs-TLA for total pleural TB was 43.7% (34.5∼53.3%), higher than that of TLA 29.1% (21.2∼38.5%) and LJ 26.2% (18.7∼35.5%) (p < 0.01), and all specificity was 100% in the diagnosis of pleural TB. Median time to detection of a positive culture was 11.8 days (95% CI 10.4∼13.4) for Rpfs-TLA, 21.0 days (95% CI 19.1∼22.9) for TLA, and 30.5 days (95% CI 28.5∼32.5) for LJ (p < 0.001). CONCLUSION: Rpfs-TLA is an accurate, rapid, cheap, and easy culture method, which makes it promising for use in clinical laboratories.

16.
J Org Chem ; 87(5): 3286-3295, 2022 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-35188765

RESUMEN

An electrochemistry-promoted oxidative cleavage of (sp3)C-C(sp3)/H bonds in alkylarenes was developed. Various aryl alkanes can be smoothly converted into ketones/aldehydes under aerobic conditions using a user-friendly undivided cell setup. The features of air as oxidant, scalability, and mild conditions make them attractive in synthetic organic chemistry.


Asunto(s)
Aldehídos , Cetonas , Aldehídos/química , Alcanos , Catálisis , Estrés Oxidativo
17.
BMC Public Health ; 21(1): 1900, 2021 10 20.
Artículo en Inglés | MEDLINE | ID: mdl-34670542

RESUMEN

BACKGROUND: In recent years, HIV testing has become one of the effective strategies to reduce the risk of the infection. Frequent quarterly HIV testing can be cost effective. Therefore, an in-depth study of factors related to the testing behavior of men who have sex with men (MSM) were analyzed to optimize intervention strategies. METHODS: From March 2011 to October 2018, the project was implemented in a Tianjin (China) bathhouse, and 5165 MSM were surveyed using snowball sampling. Factors related to HIV testing behavior were analyzed by ordinal logistic regression analysis after grouping according to testing frequency, and comprehensive analysis was performed. RESULTS: The multivariate logistic analysis showed that 6 variables including young MSM (OR = 0.67, 95% CI: 0.49-0.92, p = 0.01), low-educated MSM (OR = 0.60, 95% CI: 0.48-0.77, p < 0.0001), low HIV/AIDS knowledge (95% CI: 0.57-0.83, p < 0.0001), marital status (OR = 1.30, 95% CI: 1.07-1.57, p = 0.007), acceptance of condom promotion and distribution (OR = 14.52, 95% CI: 12.04-17.51, p < 0.0001), and frequency of condom use (p < 0.05) could link to HIV testing behaviors. CONCLUSIONS: In order to achieve the 95-95-95 goal, target publicity, HIV/AIDS education and promotion of HIV self-testing kits should be carried out to encourage frequent HIV testing among MSM who are young (especially students), married to women, poorly educated and who are reluctant to always use condoms.


Asunto(s)
Infecciones por VIH , Minorías Sexuales y de Género , China/epidemiología , Condones , Femenino , Infecciones por VIH/diagnóstico , Infecciones por VIH/epidemiología , Infecciones por VIH/prevención & control , Prueba de VIH , Homosexualidad Masculina , Humanos , Masculino , Factores de Riesgo , Conducta de Reducción del Riesgo , Conducta Sexual , Encuestas y Cuestionarios
18.
J Org Chem ; 86(17): 12460-12466, 2021 09 03.
Artículo en Inglés | MEDLINE | ID: mdl-34382805

RESUMEN

Free radical-initiated cascade cyclization of unactivated alkenes with chloralkanes, which undergoes selective activation of the α-C(sp3)-H bond of chloralkanes, provides a protocol for the synthesis of chlorinated heterocycles or polycyclic compounds. A series of radical inhibition experiments, radical capture operations, and radical clock tests were studied in this system.


Asunto(s)
Alquenos , Compuestos Policíclicos , Ciclización , Radicales Libres
19.
Org Lett ; 23(10): 4057-4061, 2021 05 21.
Artículo en Inglés | MEDLINE | ID: mdl-33955764

RESUMEN

A site-specific oxidation of (sp3)C-C(sp3) and (sp3)C-H bonds in aryl alkanes by the use of NaNO2/HCl was explored. The method is chemical-oxidant-free, transition-metal-free, uses water as the solvent, and proceeds under mild conditions, making it valuable and attractive to synthetic organic chemistry.

20.
Org Lett ; 23(8): 3207-3210, 2021 04 16.
Artículo en Inglés | MEDLINE | ID: mdl-33821663

RESUMEN

A direct and site-specific alkylation of (sp3)C-H bond with aliphatic boronic acid was achieved. By simply heating glycinates and amines together with alkylboronic acids under an oxygen atmosphere, a variety of unnatural α-amino acids and peptides could be obtained in good yields.

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