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Formation and fission of tubules from autolysosomes, endolysosomes, or phagolysosomes are required for lysosome reformation. However, the mechanisms governing these processes in these different lysosomal organelles are poorly understood. Thus, the role of phosphatidylinositol-4-phosphate (PI(4)P) is unclear as it was shown to promote the formation of tubules from phagolysosomes but was proposed to inhibit tubule formation on autolysosomes because the loss of PI4KIIIβ causes extensive lysosomal tubulation. Using super-resolution live-cell imaging, we show that Arf1-PI4KIIIβ positive vesicles are recruited to tubule fission sites from autolysosomes, endolysosomes, and phagolysosomes. Moreover, we show that PI(4)P is required to form autolysosomal tubules and that increased lysosomal tubulation caused by loss of PI4KIIIβ represents impaired tubule fission. At the site of fission, we propose that Arf1-PI4KIIIβ positive vesicles mediate a PI(3)P signal on lysosomes in a process requiring the lipid transfer protein SEC14L2. Our findings indicate that Arf1-PI4KIIIβ positive vesicles and their regulation of PI(3)P are critical components of the lysosomal tubule fission machinery. [ABSTRACT FROM AUTHOR]

Membrane-bound organelles in eukaryotic cells form an interactive network to coordinate and facilitate cellular functions. The formation of close contacts, termed "membrane contact sites" (MCSs), represents an intriguing strategy for organelle interaction and coordinated interplay. Emerging research is rapidly revealing new details of MCSs. They represent ubiquitous and diverse structures, which are important for many aspects of cell physiology and homeostasis. Here, we provide a comprehensive overview of the physiological relevance of organelle contacts. We focus on mitochondria, peroxisomes, the Golgi complex and the plasma membrane, and discuss the most recent findings on their interactions with other subcellular organelles and their multiple functions, including membrane contacts with the ER, lipid droplets and the endosomal/lysosomal compartment. Unlabelled Image • Membrane contact sites (MCSs) physically and functionally link organelles. • MCSs are ubiquitous, diverse and dynamic. • Mitochondria, ER, peroxisomes, Golgi and plasma membrane all form numerous MCSs. • MCSs facilitate intracellular signalling, lipid and metabolite transfer. • MCSs are important for organelle dynamics, division and inheritance. [ABSTRACT FROM AUTHOR]

Objective This study aimed to assess factors that influence patients' decisions in accepting prenatal diagnostic testing following genetic counseling for increased risk of fetal aneuploidy. Methods This is a retrospective cohort study of women at increased risk of fetal aneuploidy and genetic disorders who had genetic counseling from January 2012 to December 2016 at a single academic center. Demographics, indications for genetic counseling, and rates of diagnostic testing were collected and compared between those who accepted diagnostic testing and those who chose cell free DNA. The variables were analyzed using Chi-square, Fisher's exact test, and multiple logistic regression. Result Of the 2,373 pregnant women who underwent genetic counseling for increased risk of fetal aneuploidy and genetic disorders during the study period, 321 women had diagnostic testing (13.5%). Women at 35 years and older accepted diagnostic testing more than women younger than 35 years (20.7 vs. 11.5%, p < 0.001). Asian women accepted diagnostic testing at 27.7% more than white, non-Hispanic Black, and Hispanic women at 18.0, 12.1, and 11.7%, respectively, p = 0.002. Number of indications for genetic counseling influenced the likelihood of accepting diagnostic testing. Women with one indication had 11.5% acceptance of diagnostic testing, and with two and three indications, it was 17.0 and 29.2%, respectively. The commonest indication for diagnostic testing was cystic hygroma (risk ratio [RR] = 7.5, 95% confidence interval [CI]: 3.12–8.76 p < 0.001). The relative risk of diagnostic testing for fetuses with shortened long bones, femur and humerus, thickened nuchal fold, echogenic bowel, single umbilical artery, and increased nuchal translucency were 4.0, 3.3, 3.1, 2.7, and 2.7, respectively. Abnormal serum analyte alone was associated with less acceptance of diagnostic testing (RR = 0.8, 95% CI: 0.7–0.96, p = 0.017). Conclusion Age, race, ethnicity, and cumulative number of indications for genetic counseling influenced acceptance of diagnostic testing in at-risk women of fetal aneuploidy and genetic disorders. Key Points Genetic counseling. Fetal aneuploidy. Genetic disorders. Prenatal diagnostic testing. Prenatal diagnostic testing in women with increased risk of fetal aneuploidy and genetic disorders. [ABSTRACT FROM AUTHOR]

Longer glucan chains tend to precipitate. Glycogen, by far the largest mammalian glucan and the largest molecule in the cytosol with up to 55 000 glucoses, does not, due to a highly regularly branched spherical structure that allows it to be perfused with cytosol. Aberrant construction of glycogen leads it to precipitate, accumulate into polyglucosan bodies that resemble plant starch amylopectin and cause disease. This pathology, amylopectinosis, is caused by mutations in a series of single genes whose functions are under active study toward understanding the mechanisms of proper glycogen construction. Concurrently, we are characterizing the physicochemical particularities of glycogen and polyglucosans associated with each gene. These genes include GBE1, EPM2A and EPM2B, which respectively encode the glycogen branching enzyme, the glycogen phosphatase laforin and the laforin-interacting E3 ubiquitin ligase malin, for which an unequivocal function is not yet known. Mutations in GBE1 cause a motor neuron disease (adult polyglucosan body disease), and mutations in EPM2A or EPM2B a fatal progressive myoclonus epilepsy (Lafora disease). RBCK1 deficiency causes an amylopectinosis with fatal skeletal and cardiac myopathy (polyglucosan body myopathy 1, OMIM# 615895). RBCK1 is a component of the linear ubiquitin chain assembly complex, with unique functions including generating linear ubiquitin chains and ubiquitinating hydroxyl (versus canonical amine) residues, including of glycogen. In a mouse model we now show (i) that the amylopectinosis of RBCK1 deficiency, like in adult polyglucosan body disease and Lafora disease, affects the brain; (ii) that RBCK1 deficiency glycogen, like in adult polyglucosan body disease and Lafora disease, has overlong branches; (iii) that unlike adult polyglucosan body disease but like Lafora disease, RBCK1 deficiency glycogen is hyperphosphorylated; and finally (iv) that unlike laforin-deficient Lafora disease but like malin-deficient Lafora disease, RBCK1 deficiency's glycogen hyperphosphorylation is limited to precipitated polyglucosans. In summary, the fundamental glycogen pathology of RBCK1 deficiency recapitulates that of malin-deficient Lafora disease. Additionally, we uncover sex and genetic background effects in RBCK1 deficiency on organ- and brain-region specific amylopectinoses, and in the brain on consequent neuroinflammation and behavioural deficits. Finally, we exploit the portion of the basic glycogen pathology that is common to adult polyglucosan body disease, both forms of Lafora disease and RBCK1 deficiency, namely overlong branches, to show that a unified approach based on downregulating glycogen synthase, the enzyme that elongates glycogen branches, can rescue all four diseases. [ABSTRACT FROM AUTHOR]

: BackgroundWest Nile virus is an emerging pathogen in the United States. Although most cases are subclinical, serious infection can occur in the form of fulminant meningoencephalitis.: CaseWe present a case of West Nile virus meningoencephalitis complicating pregnancy. The patient presented in the second trimester with fever, nuchal rigidity, and mental status changes. The diagnosis was made by demonstrating the presence of immunoglobulin M antibody to West Nile virus in the cerebrospinal fluid. Gradual clinical improvement was noted after several days of supportive care. No obvious fetal consequences of infection were noted after birth.: ConclusionObstetricians and health care providers need to be mindful of West Nile virus infection in pregnant women presenting with fever and neurological signs, particularly in endemic areas. [Copyright &y& Elsevier]

Although multigene panel testing (MGPT) is increasingly utilized in clinical practice, there remain limited data on patient‐reported outcomes. BRCA 1/2 negative patients were contacted and offered MGPT. Patients completed pre‐ and posttest counseling, and surveys assessing cognitive, affective and behavioral outcomes at baseline, postdisclosure and 6 and 12 months. Of 317 eligible BRCA1/2 negative patients who discussed the study with research staff, 249 (79%) enrolled. Decliners were more likely to be older, non‐White, and recruited by mail or email. Ninety‐five percent of enrolled patients proceeded with MGPT. There were no significant changes in anxiety, depression, cancer specific distress or uncertainty postdisclosure. There were significant but small increases in knowledge, cancer‐specific distress and depression at 6‐12 months. Uncertainty declined over time. Those with a VUS had significant decreases in uncertainty but also small increases in cancer specific distress at 6 and 12 months. Among those with a positive result, medical management recommendations changed in 26% of cases and 2.6% of all tested. Most BRCA1/2 negative patients have favorable psychosocial outcomes after receipt of MGPT results, although small increases in depression and cancer‐specific worry may exist and may vary by result. Medical management changed in few patients. [ABSTRACT FROM AUTHOR]

Purpose: Understanding the outcomes of returning individual genetic research results to participants is critical because some genetic variants are found to be associated with health outcomes and have become available for clinical testing. Materials and Methods: BRCA1/2 -negative women with early-onset breast cancer, multiple primary cancers, or a family history of breast cancer who participated in a gene discovery cancer registry were offered the opportunity to learn their individual genetic research results of 24 breast cancer susceptibility genes with a genetic counselor after predisclosure genetic counseling. Outcomes included uptake of research results, knowledge, informed choice, psychosocial adjustment, uncertainty, satisfaction, and uptake of clinical confirmation testing. Results: Four hundred two potential participants were contacted. One hundred ninety-four participants (48%) did not respond despite multiple attempts, and 85 participants (21%) actively or passively declined. One hundred seven participants (27%) elected for predisclosure counseling and were more likely to be younger, married, and white. Ninety percent of participants who had predisclosure counseling elected to receive their genetic research results, and 89% made an informed choice. Knowledge increased significantly after predisclosure counseling, and anxiety, intrusive cancer-specific distress, uncertainty, and depression declined significantly after receipt of results. General anxiety and intrusive cancer-specific distress declined significantly for both participants with a positive result and those with a negative result. Sixty-four percent of participants had clinical confirmation testing when recommended, including all participants with a mutation in a high-penetrance gene. Conclusion: Uptake of genetic research results may be lower than anticipated by hypothetical reports and small select studies. Participants who elected to receive research results with genetic providers did not experience increases in distress or uncertainty, but not all patients return for confirmation testing. [ABSTRACT FROM AUTHOR]

Purpose Women at elevated risk for breast cancer are motivated to reduce their risk. Current approaches rely primarily on hormonal intervention. A preventive exercise intervention might address the same hormonal issues, yet have fewer serious side effects and less negative impact on quality of life as compared to prophylactic mastectomy. WISER Sister was a randomized controlled trial which examined effects of two doses of exercise training on endogenous sex hormone exposure, hormonally active breast tissue, and other breast cancer risk factors. Methods Subjects for this single site trial were recruited from across the U.S., in collaboration with organizations that serve women at elevated risk, via emails, flyers, and letters. Eligibility criteria included age ≥ 18, eumenorrheic, and at elevated risk for breast cancer (e.g. BRCA1 or BRCA2 mutation and/or ≥ 18% lifetime risk according to prediction models). A 1:1:1 randomization scheme was used to allocate participants into: control, low dose (150 min/week), or high dose (300 min/week) home based treadmill exercise. Participants provided first morning urine samples daily for two menstrual cycles at study beginning and end for calculation of endogenous hormone exposure. In addition, women completed breast dynamic contrast enhanced magnetic resonance imaging, a fasting blood draw, a treadmill exercise test, and surveys at baseline and follow-up. Discussion WISER Sister randomized 139 women, 122 of whom completed the study. The overall drop-out rate was 12%. Findings will be useful in understanding the potential for exercise to assist with reducing risk for breast cancer among women at elevated risk. [ABSTRACT FROM AUTHOR]

Background: While there is increasing interest in sharing genetic research results with participants, how best to communicate the risks, benefits and limitations of research results remains unclear. Methods: Participants who received genetic research results answered open and closed‐ended questions about their experiences receiving results and interest in and advantages and disadvantages of a web‐based alternative to genetic counseling. Results: 107 BRCA1/2 negative women with a personal or family history of breast cancer consented to receive genetic research results and 82% completed survey items about their experience. Most participants reported there was nothing they disliked (74%) or would change (85%) about their predisclosure or disclosure session (78% and 89%). They most frequently reported liking the genetic counselor and learning new information. Only 24% and 26% would not be willing to complete predisclosure counseling or disclosure of results by a web‐based alternative, respectively. The most frequently reported advantages included convenience and reduced time. Disadvantages included not being able to ask questions, the risk of misunderstanding and the impersonal nature of the encounter. Conclusion: Most participants receiving genetic research results report high satisfaction with telephone genetic counseling, but some may be willing to consider self‐directed web alternatives for both predisclosure genetic education and return of results. [ABSTRACT FROM AUTHOR]