Nickel-Catalyzed Highly Selective Radical C-C Coupling from Carboxylic Acids with Photoredox Catalysis.

Controlling the cross-coupling reaction between two different radicals is a long-standing challenge due to the process occurring statistically, which would lead to three products, including two homocoupling products and one cross-coupling product. Generally, the cross-coupling selectivity is achieved by the persistent radical effect (PRE) that requires the presence of a persistent radical and a transient radical, thus resulting in limited radical precursors. In this paper, a highly selective cross-coupling of alkyl radicals with acyl radicals to construct C(sp2)-C(sp3) bonds, or with alkyl radicals to construct C(sp3)-C(sp3) bonds have been achieved with the readily available carboxylic acids and their derivatives (NHPI ester) as coupling partners. The success originates from the use of tridentate ligand (2,2' : 6',2''-terpyridine) to enable radical cross-coupling process to Ni-mediated organometallic mechanism. This protocol offers a facile and flexible access to structurally diverse ketones (up to 90 % yield), and also a new solution for the challenging double decarboxylative C(sp3)-C(sp3) coupling. The broad utility and functional group tolerance are further illustrated by the late-stage functionalization of natural-occurring carboxylic acids and drugs.

Photoinduced activation of alkyl chlorides.

In recent years, the activation of unactivated alkyl chlorides through light-induced processes has emerged as a promising field in radical chemistry, and has led to new transformations in organic synthesis. Direct utilization of alkyl chlorides as C(sp3)-hybridized electrophiles enables the facile construction of carbon-carbon and carbon-heteroatom bonds. Furthermore, recent studies in medicinal chemistry indicate that their presence is associated with high levels of success in clinical trials. This review summarizes the recent advances in the photoinduced activation of unactivated alkyl chlorides and discusses the mechanistic aspects underlying these reactions. We anticipate that this review will serve as a valuable resource for researchers in the field of unactivated chemical bond functionalization, and inspire considerable developments in organic chemistry, drug synthesis, materials science and other related disciplines.

Dinuclear-gold-catalyzed cyclization of 1,7-enynes with alkyl bromides.

Dinuclear-gold-catalyzed radical difunctionalization of alkyl bromides with 1,7-enynes has been established via dehalogenation and 1,5-HAT processes. This protocol was used to construct, in a facile and efficient manner, a wide range of cyclopenta[c]quinolines bearing two quaternary carbon centers with good yields (28 examples, up to 84% yield). The good functional group compatibility and gram-scale preparation ability of the reaction proved its synthetic robustness.

Microbial colonization and degradation of marine microplastics in the plastisphere: A review.

Marine microplastic pollution is a growing problem for ecotoxicology that needs to be resolved. In particular, microplastics may be carriers of "dangerous hitchhikers," pathogenic microorganisms, i.e., Vibrio. Microplastics are colonized by bacteria, fungi, viruses, archaea, algae and protozoans, resulting in the biofilm referred to as the "plastisphere." The microbial community composition of the plastisphere differs significantly from those of surrounding environments. Early dominant pioneer communities of the plastisphere belong to primary producers, including diatoms, cyanobacteria, green algae and bacterial members of the Gammaproteobacteria and Alphaproteobacteria. With time, the plastisphere mature, and the diversity of microbial communities increases quickly to include more abundant Bacteroidetes and Alphaproteobacteria than natural biofilms. Factors driving the plastisphere composition include environmental conditions and polymers, with the former having a much larger influence on the microbial community composition than polymers. Microorganisms of the plastisphere may play key roles in degradation of plastic in the oceans. Up to now, many bacterial species, especially Bacillus and Pseudomonas as well as some polyethylene degrading biocatalysts, have been shown to be capable of degrading microplastics. However, more relevant enzymes and metabolisms need to be identified. Here, we elucidate the potential roles of quorum sensing on the plastic research for the first time. Quorum sensing may well become a new research area to understand the plastisphere and promote microplastics degradation in the ocean.

Stakeholders' solutions to antiretroviral therapy interruption during the COVID-19 pandemic in China: a short report.

Obtaining antiretroviral therapy (ART) was a challenge for people living with HIV (PLHIV) in China during the COVID-19 outbreak. On 26 January 2020, the Chinese Center for AIDS/STD Control and Prevention issued a nationwide directive to relax restrictions on where and when PLHIV could refill ART. This qualitative study explored unexpected barriers under this directive and recommendations to improve future ART delivery. Between February 11 and February 15 2020, in-depth interviews of 4 groups of stake holders related to ART refilling (i.e., PLHIV, community-based organization employees, CDC staff, infectious disease physicians and nurses), were conducted via WeChat. Data were managed by NVivo 11.0 and transcripts were coded using thematic analysis. Sixty-two interviews were conducted. The main barriers to refilling ART included: (1) inconsistent documentation requirements to refill ART, (2) lack of specific protocols on ART refilling, (3) insufficient staffing, and (4) regimen verification and drug shortages. The most common recommendations to improve future ART delivery were: (1) to establish a nationwide system to distribute ART and (2) increase the number of pills delivered with each ART refill. Strengthening protocols and systems to refill ART and improving collaboration is key to preventing interruptions in ART among PLHIV during public health emergencies.

Pediatric HIV Pre-test Informational Video is Associated with Higher Knowledge Scores Compared to Counselor-Delivered Information.

Video-based pre-test information is used in high resource settings to increase HIV testing coverage but remains untested in resource-limited settings. We conducted formative and evaluative focus group discussions with healthcare workers (HCWs) and caregivers of children in Kenya to develop and refine a pediatric HIV pre-test informational video. We then assessed HIV knowledge among caregivers sequentially enrolled in one of three pre-test information groups: (1) individual HCW-led (N = 50), (2) individual video-based (N = 50), and (3) group video-based (N = 50) sessions. A brief video incorporating information on national pediatric testing, modes of HIV transmission, and dramatized testimonials of caregivers who tested children was produced in three languages. Compared to individual HCW-led sessions (mean: 7.2/9; standard deviation [SD]: 1.3), both the group video-based (mean: 7.7; SD: 0.9) and individual video-based (mean: 7.6; SD: 0.9) sessions had higher mean knowledge scores. Video-based pre-test information could enhance existing pediatric HIV testing services.

Brief Report: Pediatric Saliva-Based HIV Testing: Health care Worker and Caregiver Acceptability.

BACKGROUND: Pediatric HIV testing remains suboptimal. The OraQuick test [saliva-based test (SBT)] is validated in pediatric populations ≥18 months. Understanding caregiver and health care worker (HCW) acceptability of pediatric SBT is critical for implementation. METHODS: A trained qualitative interviewer conducted 8 focus group discussions (FGDs): 4 with HCWs and 4 with caregivers of children seeking health services in western Kenya. FGDs explored acceptability of pediatric SBT and home- and facility-based SBT use. Two reviewers conducted consensus coding and thematic analyses of transcripts using Dedoose. RESULTS: Most HCWs but few caregivers had heard of SBT. Before seeing SBT instructions, both had concerns about potential HIV transmission through saliva, which were mostly alleviated after kit demonstration. Noted benefits of SBT included usability and avoiding finger pricks. Benefits of facility-based pediatric SBT included shorter client waiting and service time, higher testing coverage, and access to HCWs, while noted challenges included ensuring confidentiality. Benefits of caregivers using home-based SBT included convenience, privacy, decreased travel costs, increased testing, easier administration, and child comfort. Perceived challenges included not receiving counseling, disagreements with partners, child neglect, and negative emotional response to a positive test result. Overall, HCWs felt that SBT could be used for pediatric HIV testing but saw limited utility for caregivers performing SBT without an HCW present. Caregivers saw utility in home-based SBT but wanted easy access to counseling in case of a positive test result. CONCLUSIONS: SBT was generally acceptable to HCWs and caregivers and is a promising strategy to expand testing coverage.

Stakeholder efforts to mitigate antiretroviral therapy interruption among people living with HIV during the COVID-19 pandemic in China: a qualitative study.

INTRODUCTION: The COVID-19 pandemic has affected antiretroviral therapy (ART) continuity among people living with HIV (PLHIV) worldwide. We conducted a qualitative study to explore barriers to ART maintenance and solutions to ART interruption when stringent COVID-19 control measures were implemented in China, from the perspective of PLHIV and relevant key stakeholders. METHODS: Between 11 February and 15 February 2020, we interviewed PLHIV, community-based organization (CBO) workers, staff from centres for disease control and prevention (CDC) at various levels whose work is relevant to HIV care (CDC staff), HIV doctors and nurses and drug vendors from various regions in China. Semi-structured interviews were conducted using a messaging and social media app. Challenges and responses relevant to ART continuity during the COVID-19 pandemic were discussed. Themes were identified by transcript coding and mindmaps. RESULTS: Sixty-four stakeholders were recruited, including 16 PLHIV, 17 CBO workers, 15 CDC staff, 14 HIV doctors and nurses and two drug vendors. Many CDC staff, HIV doctors and nurses responsible for ART delivery and HIV care were shifted to COVID-19 response efforts. Barriers to ART maintenance were (a) travel restrictions, (b) inadequate communication and bureaucratic obstacles, (c) shortage in personnel, (d) privacy concerns, and (e) insufficient ART reserve. CBO helped PLHIV maintain access to ART through five solutions identified from thematic analysis: (a) coordination to refill ART from local CDC clinics or hospitals, (b) delivery of ART by mail, (c) privacy protection measures, (d) mental health counselling, and (e) providing connections to alternative sources of ART. Drug vendors contributed to ART maintenance by selling out-of-pocket ART. CONCLUSIONS: Social and institutional disruption from COVID-19 contributed to increased risk of ART interruption among PLHIV in China. Collaboration among key stakeholders was needed to maintain access to ART, with CBO playing an important role. Other countries facing ART interruption during current or future public health emergencies may learn from the solutions employed in China.