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Mammalian vaults are ribonucleoprotein (RNP) complexes, composed of a small ribonucleic acid and three proteins of 100, 193, and 240 kD in size. The 100-kD major vault protein (MVP) accounts for >70% of the particle mass. We have identified the 193-kD vault protein by its interaction with the MVP in a yeast two-hybrid screen and confirmed its identity by peptide sequence analysis. Analysis of the protein sequence revealed a region of approximately 350 amino acids that shares 28% identity with the catalytic domain of poly(ADP-ribose) polymerase (PARP). PARP is a nuclear protein that catalyzes the formation of ADP-ribose polymers in response to DNA damage. The catalytic domain of p193 was expressed and purified from bacterial extracts. Like PARP, this domain is capable of catalyzing a poly(ADP-ribosyl)ation reaction; thus, the 193-kD protein is a new PARP. Purified vaults also contain the poly(ADP-ribosyl)ation activity, indicating that the assembled particle retains enzymatic activity. Furthermore, we show that one substrate for this vault-associated PARP activity is the MVP. Immunofluorescence and biochemical data reveal that p193 protein is not entirely associated with the vault particle, suggesting that it may interact with other protein(s). A portion of p193 is nuclear and localizes to the mitotic spindle.

There are over 1.4 million adolescents living with HIV in sub-Saharan Africa, the majority of whom acquired the virus through perinatal transmission (PHIV). HIV stigma is particularly high among adolescents living with HIV and is associated with several outcomes that worsen health and increase the risk of onward HIV transmission. We tested associations between internalized HIV stigma and four of these outcomes over a one-year period among a sample of adolescent boys living with PHIV in Soweto, South Africa. Participants (N = 241) answered questions about internalized HIV stigma at baseline. They completed weekly mobile surveys over the following year to answer questions about their experiences with depression, binge drinking, medication adherence, and violence victimization. Using generalized linear mixed models, we found that baseline internalized HIV stigma was associated with increased odds of depression (OR 1.74), alcohol misuse (OR 2.09), and violence victimization (OR 1.44) and decreased odds of medication adherence (OR 0.60) over the course of a year. These outcomes negatively impact the health and wellbeing of adolescents living with PHIV and increase their risk of transmitting HIV to their partners in the future. Our findings provide novel, longitudinal evidence for the deleterious effects of HIV stigma. To improve health outcomes for adolescents with PHIV, it will be crucial to develop effective HIV stigma reduction interventions that address specific developmental, gendered, and cultural experiences., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Over one million people in the United States are transgender, nonbinary, or gender expansive (TGE). TGE individuals, particularly those who have pursued gender-affirming care, often need to disclose their identities in the process of seeking healthcare. Unfortunately, TGE individuals often report negative experiences with healthcare providers (HCPs). We conducted a cross-sectional online survey of 1684 TGE people assigned female or intersex at birth in the United States to evaluate the quality of their healthcare experiences. Most respondents (70.1%, n = 1180) reported at least one negative interaction with an HCP in the past year, ranging from an unsolicited harmful opinion about gender identity to physical attacks and abuse. In an adjusted logistic regression model, those who had pursued gender-affirming medical care (51.9% of the sample, n = 874) had 8.1 times the odds (95% CI: 4.1-17.1) of reporting any negative interaction with an HCP in the past year, compared to those who had not pursued gender-affirming care, and tended to report a higher number of such negative interactions. These findings suggest that HCPs are failing to create safe, high-quality care interactions for TGE populations. Improving care quality and reducing bias is crucial for improving the health and well-being of TGE people.

Intimate partner violence, including physical, psychological, and sexual violence, affects over one-third of Americans and is particularly common among college students. Previous work has found links between rejection sensitivity and aggressive or hostile behavior (i.e., perpetration) in intimate relationships, but this construct has only been tested as a predictor of violence in an all-male sample. A related body of work has found relationships between self-silencing and rejection sensitivity, and between self-silencing and both hostile and ingratiating behavior. The purpose of this study was to bridge these related literatures and examine the relationship between rejection sensitivity and intimate partner violence experiences and the role of self-silencing as a possible mediator. To test these relationships, we collected survey data from a sample of college students ( N = 410) at a large university in the northeast United States. Using mediation analyses, we found that rejection sensitivity predicted intimate partner violence victimization (i.e., being the target of violence) through self-silencing. Similarly, rejection sensitivity predicted intimate partner violence perpetration (i.e., being violent toward one's partner) through self-silencing. Neither gender nor race significantly moderated either path of the models. Implications of this study include incorporating individual difference variables in intimate partner violence research and programming.

The number of women with opioid use disorder (OUD) in the United States has risen precipitously. Pregnant women with OUD are a particularly vulnerable subset of addicted women with unique characteristics and needs. Many of them are impoverished, have strenuous life circumstances, are affected by past and current trauma, and have high rates of psychiatric comorbidities. Their addiction can compromise their and their infant's health, particularly without sufficient treatment including prenatal care, medication-assisted treatment (MAT), and social and behavioral care. Furthermore, these women's needs are often undetected and untreated: They may not seek appropriate prenatal and addiction care, or if they do, may face barriers to comprehensive, evidence-based treatment. Theories, methods, tools, and existing knowledge from the field of psychology are needed to improve research, prevention, and treatment for pregnant women with OUD. Although a number of psychologists have made critical contributions to research on pregnant women with OUD, we demonstrate by a scoping review of scientific literature and by examining American Psychological Association (APA) Annual Convention proceedings that much research on this population has been communicated in areas and journals outside psychology and among audiences other than psychologists. We identify relevant theoretical frameworks and methods to facilitate psychological investigation as well as evidence-based intervention and care for this population. Our field is well positioned to examine, identify, and alleviate the needs of pregnant women with OUD to improve their health and the health of their children. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Background: Population-based strategies can expand the reach of tobacco cessation treatment beyond clinical encounters., Objective: To determine the effect of two population-based tobacco cessation strategies, compared with usual care, on providing tobacco treatment outside of clinical encounters., Design: 3-arm pragmatic randomized controlled trial., Participants: Current smokers ≥ 18 years old with a primary care provider at one of five community health centers in Massachusetts were identified via the electronic health record (n = 5225) and recruited using automated phone calls., Interventions: One intervention group involved engagement with a health system-based tobacco coach (internal care coordination), and the other connected patients to a national quitline (external community referral)., Measurements: Proportion of smokers with documentation of any evidence-based cessation treatment in the 6 months after enrollment., Key Results: Of 639 individuals who responded to the proactive treatment offer, 233 consented and were randomized 1:1:1 to study arm. At 6-month follow-up, the pooled intervention group, compared with usual care, had higher documentation of any smoking cessation treatment (63% vs. 34%, p < 0.001), cessation medication prescription (52% vs. 30%, p = 0.002), and counseling (47% vs. 9%, p < 0.001). Internal care coordination was more effective than external community referral at connecting smokers to any cessation treatment (76% vs. 50%, p = 0.001) and at providing cessation medication (66% vs. 39%, p < 0.001), but comparable at linking smokers to cessation counseling resources., Conclusions: Smokers responding to a population-based, proactive outreach strategy had better provision of tobacco cessation treatment when referred to either a health system-based or community-based program compared with usual care. The health system-based strategy outperformed the quitline-based one in several measures. Future work should aim to improve population reach and test the effect on smoking cessation rates., Trial Registration: ClinicalTrials.gov NCT03612895.

Vaults are abundant large ribonucleoprotein particles. They frequently colocalize with microtubules and accumulate in filamentous actin-rich lamellipodia. To examine the movement of vaults in living cells, a chimera between the green fluorescent protein and the major vault protein was created. This fusion protein assembled into vault particles as assayed by biochemical fractionation and direct observation of living or fixed cells. By fluorescence recovery after photobleaching, we analyzed the bulk transport of vault particles into neuritic tips of PC12 cells treated with nerve growth factor. Confocal laser scanning microscopy demonstrated co-localization of the major vault protein and microtubules. Video microscopy indicated that, whereas the majority of vault particles were stationary, some individual vault particles moved rapidly, consistent with the action of a microtubule-based or actin-based molecular motor.

The major vault protein (MVP) is the predominant member of a large ribonucleoprotein particle, named vault. Vaults are abundant in the cytosol of mammalian cells. Mammalian MVP has previously been reported to be associated with the nucleus, particularly its cytosolic surface on which vaults are thought to dock at or near the nuclear pore complex. To date the presence of vault particles inside the nucleus has been convincingly reported only for sea urchin cells. We have addressed the potential nuclear localization of MVP in mammalian cells by employing confocal laser microscopy and cryo-immunoelectron microscopy. As revealed by immunostaining and by analysis of cells transfected with a construct encoding MVP and green fluorescent protein, MVP is present in both the cytosol and in the nucleus. Cryo-electron microscopy of human astroglioma U373 cells reveals clusters of immunogold particles at nuclear pores and in the nucleoplasm suggesting that nuclear MVP is associated with particulate structures. Quantification of the fluorescence observed in the cytosol and in the nuclei reveals that about 5% of the MVP in U373 cells is localized inside the nucleus. Our results further support the notion that part of the cellular MVP can enter the nucleus.

The Na-K-ATPase, or sodium pump, is comprised of two subunits, alpha and beta. Each subunit spans the lipid bilayer of the cell membrane. This review summarizes our efforts to determine how the two subunits interact to form the functional ion transporter. Our major approach has been to observe the potential for subunit assembly when one or both subunits are truncated or present as chimeras that retain only a limited region of the Na-K-ATPase. DNAs encoding these altered subunit forms of the avian Na-K-ATPase are expressed in mammalian cells. Monoclonal antibodies specific for the avian beta-subunit are then used to purify newly synthesized avian beta-subunits, and the presence of accompanying alpha-subunits indicates that subunit assembly has occurred. The ectodomain of the beta-subunit (approximately residues 62-304) is sufficient for assembly with the alpha-subunit, and a COOH-terminal truncation of the beta-subunit that lacks aminoacyl residues beyond 162 will assemble inefficiently. A maximum of 26 aminoacyl residues of the alpha-subunit are necessary for robust assembly with the beta-subunit, when this sequence replaces the COOH-terminal half of the loop between membrane spans 7 and 8 in the SERCA1 Ca-ATPase. This region of the Ca-ATPase faces the lumen of the endoplasmic reticulum. These findings encourage study of other related questions, including whether there is preferential assembly of certain subunit isoforms and how various P-type ATPases are targeted to their appropriate subcellular compartments.

cDNAs encoding Na,K-ATPase beta-subunits containing deletions in the cytoplasmic domain or in the single membrane-spanning domain of the molecule were constructed and expressed in mouse L cells to determine the effect(s) of deletions in these domains on alpha/beta-subunit assembly and intracellular targeting. Avian beta-subunits lacking some or all of the cytoplasmic domain (endodomain) assemble with the endogenous mouse alpha-subunit and are correctly transported to the plasma membrane. Mutants containing deletions in the transmembrane domain were constructed by fusing portions of cDNAs encoding the amino-terminal one-third of human beta-subunit deletion mutants with avian beta-subunit cDNA encoding the carboxyl two-thirds of the molecule. A deletion of 3 amino acids in transmembrane domain resulted in correct alpha/beta-subunit assembly and localization to the plasma membrane. In contrast, deletions of 5 or more amino acids in the transmembrane domain prevented expression of the beta-subunit at the cell surface and resulted in the accumulation of these molecules in the ER. In spite of these targeting differences, all beta-subunit mutants capable of membrane insertion were also able to assemble with the alpha-subunit. These results suggest that the specificity for alpha/beta assembly resides in the ectodomains of the subunits.

1. The effect of mental arithmetic tasks on ventilation, breathing pattern, oxygen intake and carbon dioxide output was studied during air breathing and carbon dioxide rebreathing in healthy subjects. 2. Ventilation and breathing frequency increased significantly on performance of the task during 4 min air breathing and 4 min rebreathing; tidal volume was unchanged. The slopes of the ventilatory, frequency and tidal volume responses to carbon dioxide changed little during task performance. 3. During 15 min air breathing, oxygen intake was unchanged with task performance. Carbon dioxide output increased significantly with task performance, as a result of wash-out of carbon dioxide from body stores by the increased ventilation. 4. Mental arithmetic had no effect on the coefficients of variation of the slope and position variables of the ventilatory, frequency and tidal volume responses to carbon dioxide. It is concluded that task performance does not improve the reproducibility of these responses.