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Bin Ramli MN, Lim YS, Koe CT, Demircioglu D, Tng WQ, Gonzales KAU, Tan CP, Szczerbinska I, Liang HQ, Soe EL, Lu ZP, Ariyachet C, Yu KM, Koh SH, Yaw LP, Jumat NHB, Lim JSY, Wright G, Shabbir A, Dan YY, Ng HH, Chan YS
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Human Pluripotent Stem Cell-Derived Organoids as Models of Liver Disease (opens in new window)

GASTROENTEROLOGY 2020 OCT; 159(4):1471-1486.e12
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BACKGROUND & AIMS: There are few in vitro models for studying the 3-dimensional interactions among different liver cell types during organogenesis or disease development. We aimed to generate hepatic organoids that comprise different parenchymal liver cell types and have structural features of the liver, using human pluripotent stem cells. METHODS: We cultured H1 human embryonic stem cells (WA-01, passage 27-40) and induced pluripotent stem cells (GM23338) with a series of chemically defined and serum-free media to induce formation of posterior foregut cells, which were differentiated in 3 dimensions into hepatic endoderm spheroids and stepwise into hepatoblast spheroids. Hepatoblast spheroids were reseeded in a high-throughput format and induced to form hepatic organoids; development of functional bile canaliculi was imaged live. Levels of albumin and apolipoprotein B were measured in cell culture supernatants using an enzyme-linked immunosorbent assay. Levels of gamma glutamyl transferase and alkaline phosphatase were measured in cholangiocytes. Organoids were incubated with troglitazone for varying periods and bile transport and accumulation were visualized by live-imaging microscopy. Organoids were incubated with oleic and palmitic acid, and formation of lipid droplets was visualized by staining. We compared gene expression profiles of organoids incubated with free fatty acids or without. We also compared gene expression profiles between liver tissue samples from patients with nonalcoholic steatohepatitis (NASH) versus without. We quantified hepatocyte and cholangiocyte populations in organoids using immunostaining and flow cytometry; cholangiocyte proliferation of cholangiocytes was measured. We compared the bile canaliculi network in the organoids incubated with versus without free fatty acids by live imaging. RESULTS: Cells in organoids differentiated into hepatocytes and cholangiocytes, based on the expression of albumin and cytokeratin 7. Hepatocytes were functional, based on secretion of albumin and apolipoprotein B and cytochrome P450 activity; cholangiocytes were functional, based on gamma glutamyl transferase and alkaline phosphatase activity and proliferative responses to secretin. The organoids organized a functional bile canaliculi system, which was disrupted by cholestasis-inducing drugs such as troglitazone. Organoids incubated with free fatty acids had gene expression signatures similar to those of liver tissues from patients with NASH. Incubation of organoids with free fatty acid-enriched media resulted in structural changes associated with nonalcoholic fatty liver disease, such as decay of bile canaliculi network and ductular reactions. CONCLUSIONS: We developed a hepatic organoid platform with human cells that can be used to model complex liver diseases, including NASH.
Cheleuitte-Nieves CE, Diaz LL, de la Gandara MP, Gonzalez A, Freiwald WA, de Lencastre HM, Tomasz A, Euler CW
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Evaluation of Topical Lysostaphin as a Novel Treatment for Instrumented Rhesus Macaques (Macaca mulatta) Infected with Methicillin-Resistant Staphylococcus aureus (opens in new window)

COMPARATIVE MEDICINE 2020 OCT; 70(5):335-347
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Lytic enzymes are novel antimicrobial agents that degrade bacterial cell walls, resulting in cell rupture and death. We tested one enzyme, the bacteriocin lysostaphin, for treatment of nonhuman primates (Macaca mulatta) with persistent methicillin-resistant Staphylococcus aureus (MRSA) infection of their cranial implant margins. The goal of this study was to determine if topical lysostaphin, either alone or as an adjunct therapy, could eliminate MRSA. Lysostaphin had in vitro lytic activity against all 4 previously identified NHP MRSA clones, as well as against 12 MRSA isolates of the same clonal type (MLST ST3862 and spa type t4167) before and after treatment, with no resistance discovered. In an in vivo pilot study, a 2-d application of lysostaphin alone reduced MRSA in the implant margins by 3-logs during treatment of one animal; however, MRSA titers had returned to control levels by 1 wk after treatment. In the main study, all animals (n = 4) received 10 d of systemic antibiotic treatment and both the animals and their environment (cages, equipment, room) underwent 5-d of decontamination. The experimental animals (n = 2) received 5 doses of topical lysostaphin (15 mg, every other day) applied onto their implant margins. Daily cultures showed that MRSA counts decreased significantly (<= 25 colony-forming units/mL; P < 0.05). However, sampling of the cranial implant margin 7 d after last treatment showed that MRSA counts had returned to control levels. Our study suggests that lysostaphin, coupled with other treatment modalities, can decrease MRSA infection short-term but do not completely eradicate MRSA in the long-term. This reappearance of MRSA may be due to cross-contamination or reinfection from other infected areas, an inability of the treatment to reach all colonized areas, or insufficient dosing or length of treatment. Topical lysostaphin may be more useful clinically for superficial nonimplant associated wounds in which the lytic enzyme has better access to the infected tissue.
Gleicher N, Darmon S, Molinari E, Zhang L, Hu JJ, Albertini DF, Barad DH
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A form of secondary ovarian insufficiency (SOI) due to adrenal hypoandrogenism as new infertility diagnosis (opens in new window)

ENDOCRINE 2020 OCT 2; ?(?):?
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Background Mediated via the androgen receptor on granulosa cells, models of small growing follicle stages demonstrate dependence on testosterone. Androgen deficiency reduces ovarian response to follicle stimulation hormone (FSH), granulosa cell mass and estradiol (E2) production falls and FSH, therefore, rises. Though potentially of adrenal and/or ovarian origin, androgen deficiency in association with female infertility is almost universally primarily of adrenal origin, raising the possibility that women with presumptive diagnosis of primary ovarian insufficiency (POI), also called primary ovarian failure (POF) may actually suffer from secondary ovarian insufficiency (SOI) due to adrenal hypoandrogenism that leads to follicular arrest at small-growing follicle stages. Methods This retrospective cohort study was performed in a private, academically affiliated infertility center in New York City. We searched the center's anonymized electronic research data bank for consecutive patients who presented with a diagnosis of POI, defined by age <41 year, FSH > 40.0 mIU/mL, amenorrhea for at least 6 month, and low testosterone (T), defined as total T (TT) in the lowest age-specific quartile of normal range. This study did not include patients with oophoritis. Since dehydroepiandrosterone sulfate (DHEAS) is the only androgen almost exclusively produce by adrenals, adrenal hypoandrogenism was defined by DHEAS < 100ug/dL. Thirteen of 78 presumed POI women (16.67%) qualified and represented the original study population. POI patients are usually treated with third-party egg donation; 6/13, however, rejected egg donation for personal or religious reasons and insisted on undergoing at least one last IVF cycle attempt (final study population). In preparation, they were supplemented with DHEA 25 mg TID and CoQ10 333 mg TID for at least 6 weeks prior to ovarian stimulation for IVF with FSH and human menopausal gonadotropins (hMG). Since POI patients are expected to be resistant to ovarian stimulation, primary outcome for the study was ovarian response, while secondary outcome was pregnancy/delivery. Results Though POI/POF patients usually are completely unresponsive to ovarian stimulation, to our surprise, 5/6 (83.3%) patients demonstrated an objective follicle response. In addition, 2/6 (33.3%) conceived spontaneously between IVF cycles, while on DHEA and CoQ10 supplementation and delivered healthy offspring. One of those is currently in treatment for a second child. Conclusions This preliminary report suggests that a surprising portion of young women below age 41, tagged with a diagnosis of POI/POF, due to adrenal hypoandrogenism actually suffer from a form of SOI, at least in some cases amenable to treatment by androgen supplementation. Since true POI/POF usually requires third-party egg donation, correct differentiation between POI and SOI in such women appears of great importance and may warrant a trial stimulation after androgen pre-supplementation for at least 6 weeks.
Gaebler C, Nussenzweig MC
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All eyes on the hurdle race for a SARS-CoV-2 vaccine (opens in new window)

NATURE 2020 OCT 22; 586(7830):?
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Leading COVID-19 vaccine candidates have progressed through laboratory tests at record speed. Two early clinical trials suggest that immunization delivers a favourable immune response and safety profile, but questions remain.
Kauppi PE, Ciais P, Hogberg P, Nordin A, Lappi J, Lundmark T, Wernick IK
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Carbon benefits from Forest Transitions promoting biomass expansions and thickening (opens in new window)

GLOBAL CHANGE BIOLOGY 2020 OCT; 26(10):5365-5370
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The growth of the global terrestrial sink of carbon dioxide has puzzled scientists for decades. We propose that the role of land management practices-from intensive forestry to allowing passive afforestation of abandoned lands-have played a major role in the growth of the terrestrial carbon sink in the decades since the mid twentieth century. The Forest Transition, a historic transition from shrinking to expanding forests, and from sparser to denser forests, has seen an increase of biomass and carbon across large regions of the globe. We propose that the contribution of Forest Transitions to the terrestrial carbon sink has been underestimated. Because forest growth is slow and incremental, changes in the carbon density in forest biomass and soils often elude detection. Measurement technologies that rely on changes in two-dimensional ground cover can miss changes in forest density. In contrast, changes from abrupt and total losses of biomass in land clearing, forest fires and clear cuts are easy to measure. Land management improves over time providing important present contributions and future potential to climate change mitigation. Appreciating the contributions of Forest Transitions to the sequestering of atmospheric carbon will enable its potential to aid in climate change mitigation.
Hsiao KF, Noble C, Pitman W, Yadav N, Kumar S, Keele GR, Terceros A, Kanke M, Conniff T, Cheleuitte-Nieves C, Tolwani R, Sethupathy P, Rajasethupathy P
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A Thalamic Orphan Receptor Drives Variability in Short-Term Memory (opens in new window)

CELL 2020 OCT 15; 183(2):522-536.e19
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Working memory is a form of short-term memory that involves maintaining and updating task-relevant information toward goal-directed pursuits. Classical models posit persistent activity in prefrontal cortex (PFC) as a primary neural correlate, but emerging views suggest additional mechanisms may exist. We screened similar to 200 genetically diverse mice on a working memory task and identified a genetic locus on chromosome 5 that contributes to a substantial proportion (17%) of the phenotypic variance. Within the locus, we identified a gene encoding an orphan G-protein-coupled receptor. Gpr12, which is sufficient to drive substantial and bidirectional changes in working memory. Molecular, cellular, and imaging studies revealed that Gpr12 enables high thalamus-PFC synchrony to support memory maintenance and choice accuracy. These findings identify an orphan receptor as a potent modifier of short-term memory and supplement classical PFC-based models with an emerging thalamus-centric framework for the mechanistic understanding of working memory.
Orange DE, Darnell RB
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PRIME Cells Predicting Rheumatoid Arthritis Flares (opens in new window)

NEW ENGLAND JOURNAL OF MEDICINE 2020 OCT 15; 383(16):1594-1596
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Sandifer P, Knapp L, Lichtveld M, Manley R, Abramson D, Caffey R, Cochran D, Collier T, Ebi K, Engel L, Farrington J, Finucane M, Hale C, Halpern D, Harville E, Hart L, Hswen Y, Kirkpatrick B, McEwen B, Morris G, Orbach R, Palinkas L, Partyka M, Porter D, Prather AA, Rowles T, Scott G, Seeman T, Solo-Gabriele H, Svendsen E, Tincher T, Trtanj J, Walker AH, Yehuda R, Yip F, Yoskowitz D, Singer B
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Framework for a Community Health Observing System for the Gulf of Mexico Region: Preparing for Future Disasters (opens in new window)

FRONTIERS IN PUBLIC HEALTH 2020 OCT 15; 8(?):? Article 578463
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The Gulf of Mexico (GoM) region is prone to disasters, including recurrent oil spills, hurricanes, floods, industrial accidents, harmful algal blooms, and the current COVID-19 pandemic. The GoM and other regions of the U.S. lack sufficient baseline health information to identify, attribute, mitigate, and facilitate prevention of major health effects of disasters. Developing capacity to assess adverse human health consequences of future disasters requires establishment of a comprehensive, sustained community health observing system, similar to the extensive and well-established environmental observing systems. We propose a system that combines six levels of health data domains, beginning with three existing, national surveys and studies plus three new nested, longitudinal cohort studies. The latter are the unique and most important parts of the system and are focused on the coastal regions of the five GoM States. A statistically representative sample of participants is proposed for the new cohort studies, stratified to ensure proportional inclusion of urban and rural populations and with additional recruitment as necessary to enroll participants from particularly vulnerable or under-represented groups. Secondary data sources such as syndromic surveillance systems, electronic health records, national community surveys, environmental exposure databases, social media, and remote sensing will inform and augment the collection of primary data. Primary data sources will include participant-provided information via questionnaires, clinical measures of mental and physical health, acquisition of biological specimens, and wearable health monitoring devices. A suite of biomarkers may be derived from biological specimens for use in health assessments, including calculation of allostatic load, a measure of cumulative stress. The framework also addresses data management and sharing, participant retention, and system governance. The observing system is designed to continue indefinitely to ensure that essential pre-, during-, and post-disaster health data are collected and maintained. It could also provide a model/vehicle for effective health observation related to infectious disease pandemics such as COVID-19. To our knowledge, there is no comprehensive, disaster-focused health observing system such as the one proposed here currently in existence or planned elsewhere. Significant strengths of the GoM Community Health Observing System (CHOS) are its longitudinal cohorts and ability to adapt rapidly as needs arise and new technologies develop.
Weisblum Y, Schmidt F, Zhang FW, DaSilva J, Poston D, Lorenzi JCC, Muecksch F, Rutkowska M, Hoffmann HH, Michailidis E, Gaebler C, Agudelo M, Cho A, Wang ZJ, Gazumyan A, Cipolla M, Luchsinger L, Hillyer CD, Caskey M, Robbiani DF, Rice CM, Nussenzweig MC, Hatziioannou T, Bieniasz PD
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Escape from neutralizing antibodies by SARS-CoV-2 spike protein variants (opens in new window)

ELIFE 2020 OCT 28; 9(?):? Article e61312
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Neutralizing antibodies elicited by prior infection or vaccination are likely to be key for future protection of individuals and populations against SARS-CoV-2. Moreover, passively administered antibodies are among the most promising therapeutic and prophylactic anti-SARSCoV-2 agents. However, the degree to which SARS-CoV-2 will adapt to evade neutralizing antibodies is unclear. Using a recombinant chimeric VSV/SARS-CoV-2 reporter virus, we show that functional SARS-CoV-2 S protein variants with mutations in the receptor-binding domain (RBD) and N-terminal domain that confer resistance to monoclonal antibodies or convalescent plasma can be readily selected. Notably, SARS-CoV-2 S variants that resist commonly elicited neutralizing antibodies are now present at low frequencies in circulating SARS-CoV-2 populations. Finally, the emergence of antibody-resistant SARS-CoV-2 variants that might limit the therapeutic usefulness of monoclonal antibodies can be mitigated by the use of antibody combinations that target distinct neutralizing epitopes.
Capili B
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How Does Research Start? (opens in new window)

AMERICAN JOURNAL OF NURSING 2020 OCT; 120(10):41-44
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