Characteristics of genotype, drug resistance, and molecular transmission network among newly diagnosed HIV-1 infections in Shenzhen, China.

The HIV-1 pandemic has persisted for four decades, and poses a major challenge to global public health. Shenzhen, a city with large number of migrant populations in China, is suffering HIV-1 epidemic. It is necessary to continuously conduct the molecular surveillance among newly diagnosed HIV-1 patients in these migrant population. In this study, plasma samples of newly diagnosed and ART-naive HIV-1 infections were collected from Shenzhen city in China. The partial genes of HIV-1 gag and pol were amplified and sequenced for the analysis of genotype, drug resistance, and molecular transmission network. Ninety-one sequences of pol gene were obtained from newly diagnosed HIV-1 infections in Shenzhen, and seven HIV-1 subtypes were revealed in this investigation. Among them, the circulating recombinant form (CRF) 07_BC was the mostly frequent subtype (53.8%, 49/91), followed by CRF01_AE (20.9%, 19/91), CRF55_01B (9.9%, 9/91), unique recombinant forms (URFs) (8.8%, 8/91), B (3.3%, 3/91), CRF59_01B (2.2%, 2/91), and CRF08_BC (1.1%, 1/91). The overall prevalence of pretreatment drug resistance (PDR) was 23.1% (21/91), and 52.38% (11/21) of the PDR was specific for the nonnucleotide reverse transcriptase inhibitors (NNRTIs). Furthermore, a total of 3091 pol gene sequences were used to generate 19 molecular transmission clusters, and then one growing cluster, a new cluster, and a cluster with growth reactivation were identified. The result revealed that more sexual partner, CRF_07BC subtype, and seven amino acid deletions in gag p6 region might be the influencing factors associated with the high risk of transmission behavior. Compared with CRF01_AE subtype, CRF07_BC subtype strains were more likely to form clusters in molecular transmission network. This suggests that long-term surveillance of the HIV-1 molecular transmission should be a critical measure to achieve a precise intervention for controlling the spread of HIV-1 in China.

An indispensable role for dynamin-related protein 1 in beige and brown adipogenesis.

Emerging evidence indicates that proper mitochondrial dynamics are critical for adipocyte differentiation and functional thermogenic capacity. We found that the mitochondrial fission protein dynamin-related protein 1 (DRP1, also known as DNML1) is highly expressed in brown adipose tissue compared to expression in white adipose tissue, and these expression levels increase during brown adipocyte differentiation. Our results reveal that the inhibition of DRP1 using mdivi-1 mitigates beige adipocyte differentiation and differentiation-associated mitochondrial biogenesis. We found that DRP1 is essential for the induction of the early-phase beige adipogenic transcriptional program. Intriguingly, inhibition of DRP1 is dispensable following the induction of beige adipogenesis and adipogenesis-associated mitochondrial biogenesis. Altogether, we demonstrate that DRP1 in preadipocytes plays an essential role in beige and brown adipogenesis.This article has an associated First Person interview with the first author of the paper.

Formation of the Si-B bond: insertion reactions of silylenes into B-X(X = F, Cl, Br, O, and N) bonds.

The insertion reactions of the silylene H2Si with H2BXHn-1 (X = F, Cl, Br, O, N; n = 1, 1, 1, 2, 3) have been studied by DFT and MP2 methods. The calculations show that the insertions occur in a concerted manner, forming H2Si(BH2)(XHn-1). The essences of H2Si insertions with H2BXHn-1 are the transfers of the σ electrons on the Si atom to the positive BH2 group and the electrons of X into the empty p orbital on the Si atom in H2Si. The order of reactivity in vacuum shows the barrier heights increase for the same-family element X from up to down and the same-row element X from right to left in the periodic table. The energies relating to the B-X bond in H2BXHn-1, and the bond energies of Si-X and Si-B in H2Si(BH2)(XHn-1) may determine the preference of insertions of H2Si into B-X bonds for the same-column element X or for the same-row element X. The insertion reactions in vacuum are similar to those in solvents, acetone, ether, and THF. The barriers in vacuum are lower than those in solvents and the larger polarities of solvents make the insertions more difficult to take place. Both in vacuum and in solvents, the silylene insertions are thermodynamically exothermic. Graphical Abstract The insertion process of H2Si and H2BXHn-1(X = F, Cl, Br, O, and N; n = 1, 1 , 1, 2, 3).

The insertion reactions of the p-complex silylenoid H2SiLiF with Si-X (X=F, Cl, Br, O, N) bonds.

The insertion reactions of the silylenoid H(2)SiLiF with SiH(3)XH(n-1) (X = F, Cl, Br, O, N; n = 1, 1, 1, 2, 3) have been studied by DFT calculations. The results indicate that the insertions proceed in a concerted manner, forming H(3)SiSiH(2)XH(n-1) and LiF. The essence of H(2)SiLiF insertion into Si-X bonds reactions are the donations of the electrons of X into the p orbital on the Si atom in H(2)SiLiF and the σ electrons on the Si atom in H(2)SiLiF to the positive SiH(3) group. The order of reactivity by H(2)SiLiF insertion in vacuum indicates the reaction barriers decrease for the same-row element X from right to left and the same-family element X from up down in the periodic table. The insertion reactions in ether are similar to those in vacuum. The energy barriers in vacuum are higher than those in ether. The silylenoid insertions are thermodynamically exothermic both in vacuum and in ether.