Damaged mitochondria recruit the effector NEMO to activate NF-κB signaling.

Failure to clear damaged mitochondria via mitophagy disrupts physiological function and may initiate damage signaling via inflammatory cascades, although how these pathways intersect remains unclear. We discovered that nuclear factor kappa B (NF-κB) essential regulator NF-κB effector molecule (NEMO) is recruited to damaged mitochondria in a Parkin-dependent manner in a time course similar to recruitment of the structurally related mitophagy adaptor, optineurin (OPTN). Upon recruitment, NEMO partitions into phase-separated condensates distinct from OPTN but colocalizing with p62/SQSTM1. NEMO recruitment, in turn, recruits the active catalytic inhibitor of kappa B kinase (IKK) component phospho-IKKß, initiating NF-κB signaling and the upregulation of inflammatory cytokines. Consistent with a potential neuroinflammatory role, NEMO is recruited to mitochondria in primary astrocytes upon oxidative stress. These findings suggest that damaged, ubiquitinated mitochondria serve as an intracellular platform to initiate innate immune signaling, promoting the formation of activated IKK complexes sufficient to activate NF-κB signaling. We propose that mitophagy and NF-κB signaling are initiated as parallel pathways in response to mitochondrial stress.

Mechanism of replication origin melting nucleated by CMG helicase assembly.

The activation of eukaryotic origins of replication occurs in temporally separated steps to ensure that chromosomes are copied only once per cell cycle. First, the MCM helicase is loaded onto duplex DNA as an inactive double hexamer. Activation occurs after the recruitment of a set of firing factors that assemble two Cdc45-MCM-GINS (CMG) holo-helicases. CMG formation leads to the underwinding of DNA on the path to the establishment of the replication fork, but whether DNA becomes melted at this stage is unknown1. Here we use cryo-electron microscopy to image ATP-dependent CMG assembly on a chromatinized origin, reconstituted in vitro with purified yeast proteins. We find that CMG formation disrupts the double hexamer interface and thereby exposes duplex DNA in between the two CMGs. The two helicases remain tethered, which gives rise to a splayed dimer, with implications for origin activation and replisome integrity. Inside each MCM ring, the double helix becomes untwisted and base pairing is broken. This comes as the result of ATP-triggered conformational changes in MCM that involve DNA stretching and protein-mediated stabilization of three orphan bases. Mcm2 pore-loop residues that engage DNA in our structure are dispensable for double hexamer loading and CMG formation, but are essential to untwist the DNA and promote replication. Our results explain how ATP binding nucleates origin DNA melting by the CMG and maintains replisome stability at initiation.

Establishment of CD8+ T Cell Thymic Central Tolerance to Tissue-Restricted Antigen Requires PD-1.

Highly self-reactive T cells are censored from the repertoire by both central and peripheral tolerance mechanisms upon receipt of high-affinity TCR signals. Clonal deletion is considered a major driver of central tolerance; however, other mechanisms such as induction of regulatory T cells and functional impairment have been described. An understanding of the interplay between these different central tolerance mechanisms is still lacking. We previously showed that impaired clonal deletion to a model tissue-restricted Ag did not compromise tolerance. In this study, we determined that murine T cells that failed clonal deletion were rendered functionally impaired in the thymus. Programmed cell death protein 1 (PD-1) was induced in the thymus and was required to establish cell-intrinsic tolerance to tissue-restricted Ag in CD8+ thymocytes independently of clonal deletion. In bone marrow chimeras, tolerance was not observed in PD-L1-deficient recipients, but tolerance was largely maintained following adoptive transfer of tolerant thymocytes or T cells to PD-L1-deficient recipients. However, CRISPR-mediated ablation of PD-1 in tolerant T cells resulted in broken tolerance, suggesting different PD-1 signaling requirements for establishing versus maintaining tolerance. Finally, we showed that chronic exposure to high-affinity Ag supported the long-term maintenance of tolerance. Taken together, our study identifies a critical role for PD-1 in establishing central tolerance in autoreactive T cells that escape clonal deletion. It also sheds light on potential mechanisms of action of anti-PD-1 pathway immune checkpoint blockade and the development of immune-related adverse events.

Cancer Mutations in SPOP Put a Stop to Its Inter-compartmental Hops.

In this issue of Molecular Cell, Bouchard et al. (2018) identify liquid-liquid phase separation as a mechanism for substrate-triggered localization of SPOP and ubiquitination machinery to different nuclear bodies and describe how cancer mutations disrupt this process.

Small Interfering RNA to Reduce Lipoprotein(a) in Cardiovascular Disease.

BACKGROUND: Lipoprotein(a) is a presumed risk factor for atherosclerotic cardiovascular disease. Olpasiran is a small interfering RNA that reduces lipoprotein(a) synthesis in the liver. METHODS: We conducted a randomized, double-blind, placebo-controlled, dose-finding trial involving patients with established atherosclerotic cardiovascular disease and a lipoprotein(a) concentration of more than 150 nmol per liter. Patients were randomly assigned to receive one of four doses of olpasiran (10 mg every 12 weeks, 75 mg every 12 weeks, 225 mg every 12 weeks, or 225 mg every 24 weeks) or matching placebo, administered subcutaneously. The primary end point was the percent change in the lipoprotein(a) concentration from baseline to week 36 (reported as the placebo-adjusted mean percent change). Safety was also assessed. RESULTS: Among the 281 enrolled patients, the median concentration of lipoprotein(a) at baseline was 260.3 nmol per liter, and the median concentration of low-density lipoprotein cholesterol was 67.5 mg per deciliter. At baseline, 88% of the patients were taking statin therapy, 52% were taking ezetimibe, and 23% were taking a proprotein convertase subtilisin-kexin type 9 (PCSK9) inhibitor. At 36 weeks, the lipoprotein(a) concentration had increased by a mean of 3.6% in the placebo group, whereas olpasiran therapy had significantly and substantially reduced the lipoprotein(a) concentration in a dose-dependent manner, resulting in placebo-adjusted mean percent changes of -70.5% with the 10-mg dose, -97.4% with the 75-mg dose, -101.1% with the 225-mg dose administered every 12 weeks, and -100.5% with the 225-mg dose administered every 24 weeks (P<0.001 for all comparisons with baseline). The overall incidence of adverse events was similar across the trial groups. The most common olpasiran-related adverse events were injection-site reactions, primarily pain. CONCLUSIONS: Olpasiran therapy significantly reduced lipoprotein(a) concentrations in patients with established atherosclerotic cardiovascular disease. Longer and larger trials will be necessary to determine the effect of olpasiran therapy on cardiovascular disease. (Funded by Amgen; OCEAN[a]-DOSE ClinicalTrials.gov number, NCT04270760.).

Mechanism of head-to-head MCM double-hexamer formation revealed by cryo-EM.

In preparation for bidirectional DNA replication, the origin recognition complex (ORC) loads two hexameric MCM helicases to form a head-to-head double hexamer around DNA1,2. The mechanism of MCM double-hexamer formation is debated. Single-molecule experiments have suggested a sequential mechanism, in which the ORC-dependent loading of the first hexamer drives the recruitment of the second hexamer3. By contrast, biochemical data have shown that two rings are loaded independently via the same ORC-mediated mechanism, at two inverted DNA sites4,5. Here we visualize MCM loading using time-resolved electron microscopy, and identify intermediates in the formation of the double hexamer. We confirm that both hexamers are recruited via the same interaction that occurs between ORC and the C-terminal domains of the MCM helicases. Moreover, we identify the mechanism of coupled MCM loading. The loading of the first MCM hexamer around DNA creates a distinct interaction site, which promotes the engagement of ORC at the N-terminal homodimerization interface of MCM. In this configuration, ORC is poised to direct the recruitment of the second hexamer in an inverted orientation, which is suitable for the formation of the double hexamer. Our results therefore reconcile the two apparently contrasting models derived from single-molecule experiments and biochemical data.

Sensitization of silicon by singlet exciton fission in tetracene.

Silicon dominates contemporary solar cell technologies1. But when absorbing photons, silicon (like other semiconductors) wastes energy in excess of its bandgap2. Reducing these thermalization losses and enabling better sensitivity to light is possible by sensitizing the silicon solar cell using singlet exciton fission, in which two excited states with triplet spin character (triplet excitons) are generated from a photoexcited state of higher energy with singlet spin character (a singlet exciton)3-5. Singlet exciton fission in the molecular semiconductor tetracene is known to generate triplet excitons that are energetically matched to the silicon bandgap6-8. When the triplet excitons are transferred to silicon they create additional electron-hole pairs, promising to increase cell efficiencies from the single-junction limit of 29 per cent to as high as 35 per cent9. Here we reduce the thickness of the protective hafnium oxynitride layer at the surface of a silicon solar cell to just eight angstroms, using electric-field-effect passivation to enable the efficient energy transfer of the triplet excitons formed in the tetracene. The maximum combined yield of the fission in tetracene and the energy transfer to silicon is around 133 per cent, establishing the potential of singlet exciton fission to increase the efficiencies of silicon solar cells and reduce the cost of the energy that they generate.

Association Between Achieved Low-Density Lipoprotein Cholesterol Levels and Long-Term Cardiovascular and Safety Outcomes: An Analysis of FOURIER-OLE.

BACKGROUND: Low-density lipoprotein cholesterol (LDL-C) is a well-established risk factor for atherosclerotic cardiovascular disease. However, the optimal achieved LDL-C level with regard to efficacy and safety in the long term remains unknown. METHODS: In FOURIER (Further Cardiovascular Outcomes Research With PCSK9 Inhibition in Subjects With Elevated Risk), 27 564 patients with stable atherosclerotic cardiovascular disease were randomized to evolocumab versus placebo, with a median follow-up of 2.2 years. In the open-label extension (FOURIER-OLE), 6635 of these patients were transitioned to open-label evolocumab regardless of initial treatment allocation in the parent trial and were followed for an additional median of 5 years. In this prespecified analysis, we examined the relationship between achieved LDL-C levels (an average of the first 2 LDL-C levels measured) in FOURIER-OLE (available in 6559 patients) and the incidence of subsequent cardiovascular and safety outcomes. We also performed sensitivity analyses evaluating cardiovascular and safety outcomes in the entire FOURIER and FOURIER-OLE patient population. Multivariable modeling was used to adjust for baseline factors associated with achieved LDL-C levels. RESULTS: In FOURIER-OLE, 1604 (24%), 2627 (40%), 1031 (16%), 486 (7%), and 811 (12%) patients achieved LDL-C levels of <20, 20 to <40, 40 to <55, 55 to <70, and ≥70 mg/dL, respectively. There was a monotonic relationship between lower achieved LDL-C levels-down to very low levels <20 mg/dL-and a lower risk of the primary efficacy end point (composite of cardiovascular death, myocardial infarction, stroke, hospital admission for unstable angina or coronary revascularization) and the key secondary efficacy end point (composite of cardiovascular death, myocardial infarction, or stroke) that persisted after multivariable adjustment (adjusted Ptrend<0.0001 for each end points). No statistically significant associations existed in the primary analyses between lower achieved LDL-C levels and increased risk of the safety outcomes (serious adverse events, new or recurrent cancer, cataract-related adverse events, hemorrhagic stroke, new-onset diabetes, neurocognitive adverse events, muscle-related events, or noncardiovascular death). Similar findings were noted in the entire FOURIER and FOURIER-OLE cohort up to a maximum follow-up of 8.6 years. CONCLUSIONS: In patients with atherosclerotic cardiovascular disease, long-term achievement of lower LDL-C levels, down to <20 mg/dL (<0.5 mmol/L), was associated with a lower risk of cardiovascular outcomes with no significant safety concerns. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT01764633.

CDC50A is required for aminophospholipid transport and cell fusion in mouse C2C12 myoblasts.

Myoblast fusion is essential for the formation of multinucleated muscle fibers and is promoted by transient changes in the plasma membrane lipid distribution. However, little is known about the lipid transporters regulating these dynamic changes. Here, we show that proliferating myoblasts exhibit an aminophospholipid flippase activity that is downregulated during differentiation. Deletion of the P4-ATPase flippase subunit CDC50A (also known as TMEM30A) results in loss of the aminophospholipid flippase activity and compromises actin remodeling, RAC1 GTPase membrane targeting and cell fusion. In contrast, deletion of the P4-ATPase ATP11A affects aminophospholipid uptake without having a strong impact on cell fusion. Our results demonstrate that myoblast fusion depends on CDC50A and may involve multiple CDC50A-dependent P4-ATPases that help to regulate actin remodeling.

A Counterfactual Analysis of Impact of Cesarean Birth in a First Birth on Severe Maternal Morbidity in the Subsequent Birth.

BACKGROUND: It is known that cesarean birth affects maternal outcomes in subsequent pregnancies, but specific effect estimates are lacking. We sought to quantify the effect of cesarean birth reduction among nulliparous, term, singleton, vertex (NTSV) births (i.e., preventable cesarean births) on severe maternal morbidity (SMM) in the second birth. METHODS: We examined birth certificates linked with maternal hospitalization data (2007-19) from California for NTSV births with a second birth (N = 779,382). The exposure was cesarean delivery in first birth and the outcome was SMM in the second birth. We used adjusted Poisson regression models to calculate risk ratios and population attributable fraction for SMM in the second birth and conducted a counterfactual impact analysis to estimate how lowering NTSV cesarean births could reduce SMM in second birth. RESULTS: The adjusted risk ratio for SMM in the second birth given a prior cesarean birth was 1.7 (95% CI 1.5-1.9); 15.5% (95% CI 15.3%-15.7%) of this SMM may be attributable to prior cesarean birth. In a counterfactual analysis where 12% of the California population least likely to get a cesarean birth instead delivered vaginally, we observed 174 fewer SMM events in a population of individuals with a low-risk first birth and a subsequent birth. CONCLUSIONS: In our counterfactual analysis, lowering primary cesarean birth among a NTSV population was associated with fewer downstream SMM events in subsequent births and overall. Additionally, our findings reflect the importance of considering the cumulative accrual of risks across the reproductive life-course.

Hydroxychloroquine in lupus or rheumatoid arthritis pregnancy and risk of major congenital malformations: a population-based cohort study.

OBJECTIVES: To assess the infant risk of major congenital malformations (MCM) associated with first-trimester exposure to hydroxychloroquine (HCQ) among mothers with systemic lupus erythematosus (SLE) or rheumatoid arthritis (RA). METHODS: This population-based cohort study utilised Swedish nationwide registers and included all singleton births (2006-2021) among individuals with prevalent SLE or RA in Sweden. The exposure was filling ≥1 HCQ prescription during the first trimester. The outcome was infant MCM within one year of birth. Inverse probability of treatment weighting was applied to adjust for potential confounders (e.g. maternal smoking, body mass index, pregestational diabetes, and corticosteroids). Modified Poisson regression models with robust variance estimated risk ratios and 95% confidence intervals (RR 95%CI). RESULTS: We included 1,007 births (453 exposed) and 2,500 births (144 exposed) in the SLE and RA cohorts, respectively. The MCM risks in the SLE overall cohort, exposed, and unexposed groups were 3.6%, 3.7%, and 3.4%, respectively. The corresponding figures in the RA cohort were 4.4%, 5.6%, and 4.3%, respectively. The adjusted RRs (95%CI) were 1.29 (0.65-2.56) in the SLE cohort, 1.32 (0.56-3.13) in the RA cohort, and 1.30 (0.76-2.23) in the pooled analysis. The adjusted risk difference (exposed vs unexposed) was small (0.9% in SLE and 1.3% in RA). Sensitivity analyses examining different exposure and outcome windows yielded similar findings. CONCLUSIONS: First-trimester exposure to HCQ was not associated with a significantly increased risk of MCM. HCQ's benefits may outweigh the risks in managing SLE or RA during pregnancy.

Conditional Overall Survival After Diagnosis of Non-Metastatic Colon Cancer: Impact of Laterality, MSI, and KRAS Status.

BACKGROUND: The prognostic relevance of laterality, microsatellite instability (MSI), and KRAS status in colon cancer has been established. However, their effect on conditional overall survival (COS) remains unknown. METHODS: COS is the probability of surviving additional years after a time from diagnosis. The National Cancer Database (2010-2017) was queried for adults with non-metastatic colon cancer and known mutation status undergoing curative resection. COS was investigated at 2 years. RESULTS: Of 4838 patients, 3716 survived at least 2 years: 15% had stage I, 38% stage II, and 46% stage III disease. Fifty-nine percent had a right-sided tumor, 16% were MSI-high, and 37% were mutated KRAS (mKRAS). The proportion of patients alive at 2 years was higher for stage I compared with stage II and III (65 vs. 61 vs. 54%). The 5-year overall survival for stage I-III was 80, 76, and 67% for the initial cohort, and 90, 88, and 86% for those alive at 2 years. After adjustment, higher pathologic T and N stage, tumor deposits, and no chemotherapy were associated with worse COS (p < 0.01). While laterality and MSI status were not associated with COS, mKRAS was independently associated with decreased COS (HR 1.35, 95% CI 1.12-1.62). CONCLUSION: Patients with mKRAS had worse COS, suggesting that these mutations confer an aggressive biologic behavior, with patients remaining at higher risk of death 2 years after diagnosis. Routine evaluation of KRAS status should be considered in patients with non-metastatic disease for prognostication and to identify those who might benefit from modified surveillance protocols.

Myeloid neoplasm with histiocytosis and spleen tyrosine kinase fusion responds to fostamatinib.

Not available.

The Problem of Pain in Rheumatology: Variations in Case Definitions Derived From Chronic Pain Phenotyping Algorithms Using Electronic Health Records.

OBJECTIVE: The aim of this study was to investigate and compare different case definitions for chronic pain to provide estimates of possible misclassification when researchers are limited by available electronic health record and administrative claims data, allowing for greater precision in case definitions. METHODS: We compared the prevalence of different case definitions for chronic pain (N = 3042) in patients with autoimmune rheumatic diseases. We estimated the prevalence of chronic pain based on 15 unique combinations of pain scores, diagnostic codes, analgesic medications, and pain interventions. RESULTS: Chronic pain prevalence was lowest in unimodal pain phenotyping algorithms: 15% using analgesic medications, 18% using pain scores, 21% using pain diagnostic codes, and 22% using pain interventions. In comparison, the prevalence using a well-validated phenotyping algorithm was 37%. The prevalence of chronic pain also increased with the increasing number (bimodal to quadrimodal) of phenotyping algorithms that comprised the multimodal phenotyping algorithms. The highest estimated chronic pain prevalence (47%) was the multimodal phenotyping algorithm that combined pain scores, diagnostic codes, analgesic medications, and pain interventions. However, this quadrimodal phenotyping algorithm yielded a 10% overestimation of chronic pain compared to the well-validated algorithm. CONCLUSION: This is the first empirical study to our knowledge that shows that established common modes of phenotyping chronic pain can lead to substantially varying estimates of the number of patients with chronic pain. These findings can be a reference for biases in case definitions for chronic pain and could be used to estimate the extent of possible misclassifications or corrections in using datasets that cannot include specific data elements.

Anti-SARS-CoV-2 mRNA vaccination among patients living with SLE in Sweden: Coverage and clinical effectiveness.

OBJECTIVES: To describe the uptake of anti-SARS-CoV2 vaccination in 2021 and investigate vaccine effectiveness in systemic lupus erythematosus (SLE) patients in Sweden. METHODS: The cumulative incidence of first anti-SARS-CoV2 vaccination was estimated among SLE patients from the Swedish National Patient Register and matched comparators living in Sweden on January 1, 2021. To assess vaccine effectiveness, we included the individuals who received two doses of anti-SARS-CoV2 mRNA vaccines before year 2022, with no COVID-19 diagnosis code before the 2nd vaccine dose. Hospitalization rates with COVID-19 as main diagnosis during the year after second dose were compared between SLE patients and comparators in multivariable-adjusted marginal Cox models, overall and stratified by immunosuppressive treatment received during the year before second vaccine dose. RESULTS: Vaccination uptake was similar between SLE patients and comparators. By December 2021, 9% of both SLE and comparators had not received any vaccine doses. Among 5585 SLE patients and 37,102 comparators, 11 COVID-19 hospitalizations in the SLE group and 20 in the comparators occurred. SLE was associated with a higher risk of COVID-19 hospitalization (HR = 3.47, 95%CI 1.63-7.39). The HR was higher for immunosuppressive-treated SLE (7.03 95%CI 3.00-16.46) than for immunosuppressive-untreated (1.50 95%CI 0.34-6.60). Vaccination of immunosuppressive-untreated SLE patients had similar effectiveness as comparators. CONCLUSION: Anti-SARS-CoV2 vaccination coverage was similar between SLE patients and the general population in Sweden. Even though the incidence of post-vaccination COVID-19 hospitalization was very low, vaccine effectiveness was diminished in SLE patients compared to the general population and lowest in those treated with immunosuppressants.

Patient-Informed Value Elements in Cost-Effectiveness Analyses of Major Depressive Disorder Treatment: A Literature Review and Synthesis.

OBJECTIVES: Prior work identified 6 key value elements (attributes of treatment and desired outcomes) for individuals living with major depressive disorder (MDD) in managing their condition: mode of treatment, time to treatment helpfulness, MDD relief, quality of work, interaction with others, and affordability. The objective of our study was to identify whether previous cost-effectiveness analyses (CEAs) for MDD treatment addressed any of these value elements. A secondary objective was to identify whether any study engaged patients, family members, and caregivers in the model development process. METHODS: We conducted a systematic literature review to identify published model-based CEAs. We compared the elements of the published studies with the MDD patient value elements elicited in prior work to identify gaps and areas for future research. RESULTS: Of 86 published CEAs, we found that 7 included patient out-of-pocket costs, and 32 included measures of productivity, which were both priorities for individuals with MDD. We found that only 2 studies elicited measures from patients for their model, and 2 studies engaged patients in the modeling process. CONCLUSIONS: Published CEA models for MDD treatment do not regularly include value elements that are a priority for this patient population nor do they include patients in their modeling process. Flexible models that can accommodate elements consistent with patient experience are needed, and a multistakeholder engagement approach would help accomplish this.

Celiac disease symptom profiles and their relationship to gluten-free diet adherence, mental health, and quality of life.

BACKGROUND: A subgroup of adults with celiac disease experience persistent gastrointestinal and extraintestinal symptoms, which vary between individuals and the cause(s) for which are often unclear. METHODS: The present observational study sought to elucidate patterns of persistent symptoms and the relationship between those patterns and gluten-free diet adherence, psychiatric symptoms, and various aspects of quality of life (QOL) in an online sample of adults with celiac disease. U.S. adults with self-reported, biopsy-confirmed celiac disease (N = 523; Mage = 40.3 years; 88% women; 93.5% White) voluntarily completed questionnaires as part of the iCureCeliac® research network: (a) Celiac Symptoms Index (CSI) for physical symptoms and subjective health; (b) Celiac Dietary Adherence Test for gluten-free diet adherence; (c) PROMIS-29, SF-36, and Celiac Disease Quality of Life Survey for psychiatric symptoms and QOL. Symptom profiles were derived using latent profile analysis and profile differences were examined using auxiliary analyses. RESULTS: Latent profile analysis of CSI items determined a four-profile solution fit best. Profiles were characterized by: (1) little to no symptoms and excellent subjective health (37% of sample); (2) infrequent symptoms and good subjective health (33%); (3) occasional symptoms and fair to poor subjective health (24%); (4) frequent to constant symptoms and fair to poor subjective health (6%). Profiles 2 and 3 reported moderate overall symptomology though Profile 2 reported relatively greater extraintestinal symptoms and Profile 3 reported relatively greater gastrointestinal symptoms, physical pain, and worse subjective health. Profiles differed on anxiety and depression symptoms, limitations due to physical and emotional health, social functioning, and sleep, but not clinical characteristics, gluten-free diet adherence, or QOL. Despite Profile 3's moderate symptom burden and low subjective health as reported on the CSI, Profile 3 reported the lowest psychiatric symptoms and highest quality of life on standardized measures. CONCLUSIONS: Adults with celiac disease reported variable patterns of persistent symptoms, symptom severity, and subjective health. Lack of profile differences in gluten-free diet adherence suggests that adjunctive dietary or medical assessment and intervention may be warranted. Lower persistent symptom burden did not necessarily translate to better mental health and QOL, suggesting that behavioral intervention may be helpful even for those with lower celiac symptom burden.

γδ Thymocyte Maturation and Emigration in Adult Mice.

Several unique waves of γδ T cells are generated solely in the fetal/neonatal thymus, whereas additional γδ T cell subsets are generated in adults. One intriguing feature of γδ T cell development is the coordination of differentiation and acquisition of effector function within the fetal thymus; however, it is less clear whether this paradigm holds true in adult animals. In this study, we investigated the relationship between maturation and thymic export of adult-derived γδ thymocytes in mice. In the Rag2pGFP model, immature (CD24+) γδ thymocytes expressed high levels of GFP whereas only a minority of mature (CD24-) γδ thymocytes were GFP+ Similarly, most peripheral GFP+ γδ T cells were immature. Analysis of γδ recent thymic emigrants (RTEs) indicated that most γδ T cell RTEs were CD24+ and GFP+, and adoptive transfer experiments demonstrated that immature γδ thymocytes can mature outside the thymus. Mature γδ T cells largely did not recirculate to the thymus from the periphery; rather, a population of mature γδ thymocytes that produced IFN-γ or IL-17 remained resident in the thymus for at least 60 d. These data support the existence of two populations of γδ T cell RTEs in adult mice: a majority subset that is immature and matures in the periphery after thymic emigration, and a minority subset that completes maturation within the thymus prior to emigration. Additionally, we identified a heterogeneous population of resident γδ thymocytes of unknown functional importance. Collectively, these data shed light on the generation of the γδ T cell compartment in adult mice.

Hepatitis C and Cigarette Smoking Behavior: Themes From Focus Groups.

INTRODUCTION: People with chronic hepatitis C virus (HCV; PWHC) use cigarettes at a much higher prevalence than other individuals, and smoking can exacerbate the harms specifically related to HCV (eg, hepatocellular carcinoma). Little is known about factors related to cigarette use among PWHC. AIMS AND METHODS: This study examined focus group data to explore beliefs and behaviors related to cigarette use among PWHC. Qualitative data from two focus groups of PWHC reporting current cigarette smoking (n = 15, 60% male) were collected using a semi-structured interview guide. Participants were asked about reasons for smoking, barriers to quitting smoking, and the relationship of HCV to smoking. Focus groups were transcribed verbatim and coded in NVivo 12. Four coders examined themes that arose in the focus groups. Common themes are described and supported with quotes. RESULTS: Reasons for smoking included addiction to cigarettes, stress, substituting cigarettes for other drugs, and social norms, while reasons for quitting included health and being free from the use of all drugs. Barriers to quitting included concerns about coping with stress, weight gain, and having a lack of support for and education about quitting. Many participants believed there was a link between smoking and HCV and discussed smoking in relation to the stress of an HCV diagnosis. CONCLUSIONS: Participants identified both HCV-related and non-HCV-related aspects of cigarette smoking and cessation-related behaviors that could be targeted in cessation treatment. More research is needed to identify the best treatment approaches that reduce the significant medical consequences of cigarette use among PWHC. IMPLICATIONS: People with chronic hepatitis C virus (HCV; PWHC) smoke cigarettes at a high prevalence, yet little is known about their smoking behaviors. Moreover, there are no cessation treatments targeting PWHC. This is the first study to collect focus group data from PWHC who smoke in order to identify reasons for cigarette use (HCV-related and non-HCV-related), and motivators and barriers to quitting cigarettes. PWHC reports using cigarettes to cope with the stress of an HCV diagnosis and to celebrate HCV cure. These findings suggest there are specific times during the HCV care continuum where providers can aid with cessation efforts.

Relativistic effects and pressure-induced phase transition in CsAu.

Cesium auride (CsAu) is an intriguing compound formed by two metals that, upon reacting, exhibits properties of an ionic salt. In this study, we employ computer simulations to explore the influence of relativistic effects on the structure and some physical properties of CsAu, as well as on a potential pressure-induced structural phase transition, the effect of high pressures on its electronic gap, and the possible transition to a conducting state. We have found that including relativistic effects reduces the lattice parameter of CsAu and brings its volumetric properties closer to the trend observed in alkali halides. It also enhances the charge transfer from cesium to gold, resulting in a difference of up to 0.15e, at ambient pressure, between non-relativistic and fully relativistic calculations. Additionally, upon increasing pressure, in the absence of intervening structural phase transitions, the closing of CsAu's band gap is expected at approximately 31.5 GPa. The inclusion of relativistic effects stabilizes the CsAu Pm3̄m structure and shifts the transition pressure to a possible high-pressure P4/mmm phase from 2 GPa (non-relativistic calculation) to 14 GPa (fully-relativistic calculation). Both the Pm3̄m and P4/mmm structures become dynamically unstable around 15 GPa, thus suggesting that the tetragonal structure may be an intermediate state towards a truly stable high-pressure CsAu phase.