The synthetic peptide T-20 (enfuvirtide) represents the first of a new class of antiretroviral compounds to demonstrate in vivo potency by targeting a step in viral entry. T-20 inhibits a conformational change in the human immunodeficiency virus type 1 (HIV-1) transmembrane glycoprotein (gp41) that is required for fusion between HIV-1 and target cell membranes. The initial phase I clinical trial of T-20 treatment for HIV-infected patients thus provided a unique opportunity to evaluate the emergence of resistant virus in vivo to this novel class of antiretroviral agents. All four patients who received an intermediate dose of T-20 (30 mg twice daily) had an initial decline in plasma viral load over the first 10 days but a rising trend by day 14, suggestive of selection for resistant virus. Plasma virus derived from patients enrolled in all dosage groups of the phase I T-20 trial was analyzed by population sequencing before and after treatment. While no mutations were found within a highly conserved 3-amino-acid sequence (GIV) known to be critical for fusion at baseline, after 14 days of therapy, virus from one patient in the 30-mg dose group (30-1) developed a mutation in this motif, specifically an aspartic acid (D) substitution for glycine (G) at position 36. Multiple env clones were derived from the plasma virus of all four patients in the 30-mg dosage group. Sequence analysis of 49 clones derived from the plasma of patient 30-1 on day 14 revealed that 25 clones contained the G36D mutation, while 8 contained the V38A mutation. Dual mutations involving G36D and other residues within the HR1 domain were also identified. In 5 of the 49 env clones, other mutations involving residues 32 (Q32R or Q32H) and 39 (Q39R) were found in combination with G36D. Cloned env sequences derived from the plasma virus of subject 30-3 also had single mutations in the GIV sequence (V38M and I37V) detectable following therapy with T-20. The plasma virus from subjects 30-2 and 30-4 did not contain changes within the GIV sequence. To analyze the biological resistance properties of these mutations, we developed a novel single-cycle HIV-1 entry assay using JC53BL cells which express ␤-galactosidase and luciferase under control of the HIV-1 long terminal repeat. Full-length env clones were derived from the plasma virus of patients 30-1 and 30-3 and used to generate pseudotyped virus stocks. The mean 50% inhibition concentrations (IC 50 s) for mutants G36D and V38A (patient 30-1) were 2.3 g/ml and 11.2 g/ml, respectively, statistically significant increases of 9.1-and 45-fold, respectively, compared with those of wild-type Env. The IC 50 for the V38 M mutation (patient 30-3) was 7.6 g/ml, an 8-fold increase compared with that of the wild type. The I37V mutation resulted in an IC 50 3.2-fold greater than that of the wild type. Envs with double mutations (Q32R plus G36D and Q32H plus G36D) exhibited a level of resistance similar to that of G36D alone. These findings provide the first evidence for the rapid emergence of clinical resistance to a...

The electrochemical reduction of CO to multi-carbon products has attracted much attention because it provides an avenue to the synthesis of value-added carbon-based fuels and feedstocks using renewable electricity. Unfortunately, the efficiency of CO conversion to C products remains below that necessary for its implementation at scale. Modifying the local electronic structure of copper with positive valence sites has been predicted to boost conversion to C products. Here, we use boron to tune the ratio of Cu to Cu active sites and improve both stability and C-product generation. Simulations show that the ability to tune the average oxidation state of copper enables control over CO adsorption and dimerization, and makes it possible to implement a preference for the electrosynthesis of C products. We report experimentally a C Faradaic efficiency of 79 ± 2% on boron-doped copper catalysts and further show that boron doping leads to catalysts that are stable for in excess of ~40 hours while electrochemically reducing CO to multi-carbon hydrocarbons.

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BACKGROUND: On January 20, 2020, a new coronavirus epidemic with human-to-human transmission was officially declared by the Chinese government, which caused significant public panic in China. In light of the coronavirus disease 2019 outbreak, pregnant women may be particularly vulnerable and in special need for preventive mental health strategies. Thus far, no reports exist to investigate the mental health response of pregnant women to the coronavirus disease 2019 outbreak. OBJECTIVE: This study aimed to examine the impact of coronavirus disease 2019 outbreak on the prevalence of depressive and anxiety symptoms and the corresponding risk factors among pregnant women across China. STUDY DESIGN: A multicenter, cross-sectional study was initiated in early December 2019 to identify mental health concerns in pregnancy using the Edinburgh Postnatal Depression Scale. This study provided a unique opportunity to compare the mental status of pregnant women before and after the declaration of the coronavirus disease 2019 epidemic. A total of 4124 pregnant women during their third trimester from 25 hospitals in 10 provinces across China were examined in this crosssectional study from January 1, 2020, to February 9, 2020. Of these women, 1285 were assessed after January 20, 2020, when the coronavirus epidemic was publicly declared and 2839 were assessed before this pivotal time point. The internationally recommended Edinburgh Postnatal Depression Scale was used to assess maternal depression and anxiety symptoms. Prevalence rates and risk factors were compared between the pre-and poststudy groups. RESULTS: Pregnant women assessed after the declaration of coronavirus disease 2019 epidemic had significantly higher rates of depressive symptoms (26.0% vs 29.6%, P¼.02) than women assessed before the epidemic declaration. These women were also more likely to have thoughts of self-harm (P¼.005). The depressive rates were positively associated with the number of newly confirmed cases of coronavirus disease 2019 (P¼.003), suspected infections (P¼.004), and deaths per day (P¼.001). Pregnant women who were underweight before pregnancy, primiparous, younger than 35 years, employed full time, in middle income category, and had appropriate living space were at increased risk for developing depressive and anxiety symptoms during the outbreak. CONCLUSION: Major life-threatening public health events such as the coronavirus disease 2019 outbreak may increase the risk for mental illness among pregnant women, including thoughts of self-harm. Strategies targeting maternal stress and isolation such as effective risk communication and the provision of psychological first aid may be particularly useful to prevent negative outcomes for women and their fetuses.

Mitochondria maintain tight regulation of inner mitochondrial membrane (IMM) permeability to sustain ATP production. Stressful events cause cellular calcium (Ca 2+ ) dysregulation followed by rapid loss of IMM potential known as permeability transition (PT), which produces osmotic shifts, metabolic dysfunction, and cell death. The molecular identity of the mitochondrial PT pore (mPTP) was previously unknown. We show that the purified reconstituted c-subunit ring of the F O of the F 1 F O ATP synthase forms a voltage-sensitive channel, the persistent opening of which leads to rapid and uncontrolled depolarization of the IMM in cells. Prolonged high matrix Ca 2+ enlarges the c-subunit ring and unhooks it from cyclophilin D/cyclosporine A binding sites in the ATP synthase F 1 , providing a mechanism for mPTP opening. In contrast, recombinant F 1 beta-subunit applied exogenously to the purified c-subunit enhances the probability of pore closure. Depletion of the c-subunit attenuates Ca 2+ -induced IMM depolarization and inhibits Ca 2+ and reactive oxygen species-induced cell death whereas increasing the expression or single-channel conductance of the c-subunit sensitizes to death. We conclude that a highly regulated c-subunit leak channel is a candidate for the mPTP. Beyond cell death, these findings also imply that increasing the probability of c-subunit channel closure in a healthy cell will enhance IMM coupling and increase cellular metabolic efficiency.metabolism | necrosis | apoptosis | ion channel | excitotoxicity M itochondria produce ATP by oxidative phosphorylation (OXPHOS). Leak currents in the inner mitochondrial membrane (IMM) reduce the efficiency of this process by uncoupling the electron transport system from ATP synthase activity. Many studies have described the biophysical and pharmacological features of an IMM pore [the mitochondrial permeability transition pore (mPTP)] that is responsible for a rapid IMM uncoupling, causing osmotic shifts within the mitochondrial matrix in the setting of cellular Ca 2+ dysregulation and adenine nucleotide depletion (1-4). Some studies suggest that such uncoupling also functions during physiological events and that the mPTP may transiently operate as a Ca 2+ -release channel (5-7). Although models for the molecular identity of the mPTP have been proposed (8), deletions of putative components, such as adenine nucleotide translocase (ANT) and the voltagedependent anion channel (VDAC), have failed to prevent rapid depolarizations (9). In the meantime, nonpore forming regulatory components of the mPTP, such as cyclophilin D (CypD), have been extensively investigated (10, 11).We recently reported a leak conductance sensitive to ATP/ ADP and the Bcl-2 family member B-cell lymphoma-extra large (Bcl-x L ) within the membrane of isolated submitochondrial vesicles (SMVs) enriched in ATP synthase (12, 13). We demonstrated binding of Bcl-x L within F 1 to the beta-subunit of the ATP synthase, suggesting that the channel responsible for the leak conductance lies within the memb...

The recruitment of mononuclear leukocytes and formation of intimal macrophage-rich lesions at specific sites of the arterial tree are key events in atherogenesis. Inducible endothelial cell adhesion molecules may participate in this process. In aortas of normal chow-fed wild-type mice and rabbits, vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1), but not E-selectin, were expressed by endothelial cells in regions predisposed to atherosclerotic lesion formation. En face confocal microscopy of the mouse ascending aorta and proximal arch demonstrated that VCAM-1 expression was increased on the endothelial cell surface in lesion-prone areas. ICAM-1 expression extended into areas protected from lesion formation. Hypercholesterolemia induced atherosclerotic lesion formation in rabbits, LDL receptor and apolipoprotein E knockout mice, and Northern blot analysis demonstrated increased steady-state mRNA levels of VCAM-1 and ICAM-1, but not of E-selectin. Immunohistochemical staining revealed that VCAM-1 and ICAM-1 were expressed predominantly by endothelium in early lesions and by intimal cells in more advanced lesions. In early and advanced lesions, staining was most intense in endothelial cells at and adjacent to lesion borders. ICAM-1 staining extended into the uninvolved aorta. These expression patterns were highly reproducible in both species. The only difference was that VCAM-1 expression in endothelium over the central portions of lesions was found frequently in rabbits and rarely in mice. The expression of VCAM-1 by arterial endothelium in normal animals may represent a pathogenic mechanism or a phenotypic marker of predisposition to atherogenesis.

Tissue inhibitors of metalloproteinases (TIMPs) suppress matrix metalloproteinase (MMP) activity critical for extracellular matrix turnover associated with both physiologic and pathologic tissue remodeling. We demonstrate here that TIMP-2 abrogates angiogenic factor-induced endothelial cell proliferation in vitro and angiogenesis in vivo independent of MMP inhibition. These effects require alpha 3 beta 1 integrin-mediated binding of TIMP-2 to endothelial cells. Further, TIMP-2 induces a decrease in total protein tyrosine phosphatase (PTP) activity associated with beta1 integrin subunits as well as dissociation of the phosphatase SHP-1 from beta1. TIMP-2 treatment also results in a concomitant increase in PTP activity associated with tyrosine kinase receptors FGFR-1 and KDR. Our findings establish an unexpected, MMP-independent mechanism for TIMP-2 inhibition of endothelial cell proliferation in vitro and reveal an important component of the antiangiogenic effect of TIMP2 in vivo.

Excessive inflammation occurs during infection and autoimmunity in mice lacking the alpha-subunit of the interleukin 27 (IL-27) receptor. The molecular mechanisms underlying this increased inflammation are incompletely understood. Here we report that IL-27 upregulated IL-10 in effector T cells that produced interferon-gamma and expressed the transcription factor T-bet but did not express the transcription factor Foxp3. These IFN-gamma+T-bet+Foxp3- cells resembled effector T cells that have been identified as the main source of host-protective IL-10 during inflammation. IL-27-induced production of IL-10 was associated with less secretion of IL-17, and exogenous IL-27 reduced the severity of adoptively transferred experimental autoimmune encephalomyelitis by a mechanism dependent on IL-10. Our data show that IL-27-induced production of IL-10 by effector T cells contributes to the immunomodulatory function of IL-27.