Dual role of lipids for genome stability and pluripotency facilitates full potency of mouse embryonic stem cells.

While Mek1/2 and Gsk3ß inhibition ("2i") supports the maintenance of murine embryonic stem cells (ESCs) in a homogenous naïve state, prolonged culture in 2i results in aneuploidy and DNA hypomethylation that impairs developmental potential. Additionally, 2i fails to support derivation and culture of fully potent female ESCs. Here we find that mouse ESCs cultured in 2i/LIF supplemented with lipid-rich albumin (AlbuMAX) undergo pluripotency transition yet maintain genomic stability and full potency over long-term culture. Mechanistically, lipids in AlbuMAX impact intracellular metabolism including nucleotide biosynthesis, lipid biogenesis, and TCA cycle intermediates, with enhanced expression of DNMT3s that prevent DNA hypomethylation. Lipids induce a formative-like pluripotent state through direct stimulation of Erk2 phosphorylation, which also alleviates X chromosome loss in female ESCs. Importantly, both male and female "all-ESC" mice can be generated from de novo derived ESCs using AlbuMAX-based media. Our findings underscore the importance of lipids to pluripotency and link nutrient cues to genome integrity in early development.

Assessing progression of health technology assessment implementation in Asia: a balanced scorecard for cross comparison of selected countries in Asia.

OBJECTIVE: To provide an update on the use of health technology assessment (HTA) in Asia and lessons for countries seeking to advance HTA. METHODS: Build upon the research by Chootipongchaivat and the World Health Organization identifying eighteen "factors conducive to the development of HTA in Asia." These factors were used to create a balanced scorecard to assess the progress of HTA, measuring progress against each factor in China, India, Indonesia, Malaysia, Philippines, South Korea, Taiwan, Thailand, and Vietnam. A scoring system was used wherein: 1, No progress; 2, milestone at early stages, ad hoc HTA use; 3, progress on milestone but limited impact; 4, significant progress but limited remit; and 5, significant progress on milestone, routine HTA informs decisions. Total scores indicated progress of HTA while milestone scores provided contextual insights within countries. Literature reviews and expert interviews were used to complete scorecards. RESULTS: South Korea and Thailand scored highest with seventy-three and seventy-one points, respectively, while Vietnam scored lowest at 28.5. Advanced HTA programs have independent HTA agencies with a broad remit, explicit process and methods, network of researchers, and routine use of HTA. Taiwan and Malaysia fall in a middle tier, with established HTA programs with limited remit. The final tier with China, India, Indonesia, Philippines, and Vietnam, emerging HTA processes. CONCLUSIONS: Universal Health Coverage goals have catalyzed expansion of HTA. Political will, technical expertise, and sustained financing remain challenges for sustainable HTA programs. Legislation supporting HTA is helpful but political will is key. Recommendations for regional collaboration are provided.

QSER1 protects DNA methylation valleys from de novo methylation.

DNA methylation is essential to mammalian development, and dysregulation can cause serious pathological conditions. Key enzymes responsible for deposition and removal of DNA methylation are known, but how they cooperate to regulate the methylation landscape remains a central question. Using a knockin DNA methylation reporter, we performed a genome-wide CRISPR-Cas9 screen in human embryonic stem cells to discover DNA methylation regulators. The top screen hit was an uncharacterized gene, QSER1, which proved to be a key guardian of bivalent promoters and poised enhancers of developmental genes, especially those residing in DNA methylation valleys (or canyons). We further demonstrate genetic and biochemical interactions of QSER1 and TET1, supporting their cooperation to safeguard transcriptional and developmental programs from DNMT3-mediated de novo methylation.

Exploring facilitators and barriers to introducing health technology assessment: a systematic review.

OBJECTIVE: This study aims to identify and codify the facilitators and barriers to help implementing partners institutionalize health technology assessment (HTA) successfully and navigate complex systems for health-related policy making. METHODS: We searched for peer-reviewed and gray literature articles examining HTA programs globally using six databases. Keywords used as a guide for capturing articles included "health technology assessment," "barrier," and "facilitator" and their synonyms. Search results were scrutinized for duplicates and screened through a review of titles and abstracts. A full-text review was conducted exploring articles' coverage of twenty-seven evaluation criteria across four primary areas of interest: barriers/facilitators, motivations, guidelines, and institutional frameworks. RESULTS: A total of 18,599 records were identified for duplication check, title, and abstract review. A total of 1,594 articles underwent full-text review, leading to a final synthesis of 262 studies. We found that ninety-seven articles discussed barriers/facilitators, with fifty-three of those discussing local capacity and unavailable human resources. Out of the sixty-six articles discussing motivations, forty-two cited the interest in supporting the decision-making process for, and promoting, appropriate resource allocation. Of the sixty-one articles that discussed guidelines and institutional framework, twenty-one articles described HTA as an independent national unit, and sixteen described their HTA unit as a unit within the Ministry of Health (MOH). CONCLUSIONS: This systematic review unpacks the dynamic and relevant contexts for understanding the HTA institutionalization process to help policy makers and practitioners achieve tangible progress in confronting the most critical issues facing priority setting and HTA institutionalization.

Correction to: Mass testing and treatment for malaria followed by weekly fever screening, testing and treatment in Northern Senegal: feasibility, cost and impact.

An amendment to this paper has been published and can be accessed via the original article.

Modeling polymorphic ventricular tachycardia at rest using patient-specific induced pluripotent stem cell-derived cardiomyocytes.

BACKGROUND: While mutations in the cardiac type 2 ryanodine receptor (RyR2) have been linked to exercise-induced or catecholaminergic polymorphic ventricular tachycardia (CPVT), its association with polymorphic ventricular tachycardia (PMVT) occurring at rest is unclear. We aimed at constructing a patient-specific human-induced pluripotent stem cell (hiPSC) model of PMVT occurring at rest linked to a single point mutation in RyR2. METHODS: Blood samples were obtained from a patient with PMVT at rest due to a heterozygous RyR2-H29D mutation. Patient-specific hiPSCs were generated from the blood samples, and the hiPSC-derived cardiomyocytes (CMs) were generated via directed differentiation. Using CRIPSR/Cas9 technology, isogenic controls were generated by correcting the RyR2-H29D mutation. Using patch-clamp, fluorescent confocal microscopy and video-image-based analysis, the molecular and functional properties of RyR2-H29D hiPSCCMs and control hiPSCCMs were compared. FINDINGS: RyR2-H29D hiPSCCMs exhibit intracellular sarcoplasmic reticulum (SR) Ca2+ leak through RyR2 under physiological pacing. RyR2-H29D enhances the contribution of inositol 1,4,5-trisphosphate receptors to excitation-contraction coupling (ECC) that exacerbates abnormal Ca2+ release in RyR2-H29D hiPSCCMs. RyR2-H29D hiPSCCMs exhibit shorter action potentials, delayed afterdepolarizations, arrhythmias and aberrant contractile properties compared to isogenic controls. The RyR2-H29D mutation causes post-translational remodeling that is fully reversed with isogenic controls. INTERPRETATION: To conclude, in a model based on a RyR2 point mutation that is associated with short-coupled PMVT at rest, RyR2-H29D hiPSCCMs exhibited aberrant intracellular Ca2+ homeostasis, shortened action potentials, arrhythmias and abnormal contractile properties. FUNDING: French Muscular Dystrophy Association (AFM; project 16,073, MNM2 2012 and 20,225), "Fondation de la Recherche Médicale" (FRM; SPF20130526710), "Institut National pour la Santé et la Recherche Médicale" (INSERM), National Institutes of Health (ARM; R01 HL145473) and New York State Department of Health (NYSTEM C029156).

A correlation study between meteorological parameters and COVID-19 pandemic in Mumbai, India.

BACKGROUND AND AIMS: Meteorological parameters play a major role in the transmission of infectious diseases such as COVID-19. In this study, we aim to analyze the correlation between meteorological parameters and COVID-19 pandemic in the financial capital of India, Mumbai. METHODS: In this research, we collected data from April 27 till July 25, 2020 (90 days). A Spearman rank correlation test along with two-tailed p test and an Artificial Neural Network (ANN) technique have been used to predict the associations of COVID-19 with meteorological parameters. RESULTS: A significant correlation of COVID-19 was found with temperature (Tmin), dew point (DPmax), relative humidity (RHmax, RHavg, RHmin) and surface pressure (Pmax, Pavg, Pmin). The parameters which showed significant correlation were then taken for the modeling and prediction of COVID-19 infections using Artificial Neural Network technique. CONCLUSIONS: It was found that the relative humidity and pressure parameters had the most influencing effect out of all other significant parameters (obtained from Spearman's method) on the active number of COVID-19 cases. The finding in this study might be useful for the public, local authorities, and the Ministry of Health, Govt. of India to combat COVID-19.

Sphingosine kinases protect murine embryonic stem cells from sphingosine-induced cell cycle arrest.

Sphingosine-1-phosphate (S1P) is a bioactive lipid molecule regulating organogenesis, angiogenesis, cell proliferation, and apoptosis. S1P is generated by sphingosine kinases (SPHK1 and SPHK2) through the phosphorylation of ceramide-derived sphingosine. Phenotypes caused by manipulating S1P metabolic enzymes and receptors suggested several possible functions for S1P in embryonic stem cells (ESCs), yet the mechanisms by which S1P and related sphingolipids act in ESCs are controversial. We designed a rigorous test to evaluate the requirement of S1P in murine ESCs by knocking out both Sphk1 and Sphk2 to create cells incapable of generating S1P. To accomplish this, we created lines mutant for Sphk2 and conditionally mutant (floxed) for Sphk1, allowing evaluation of ESCs that transition to double-null state. The Sphk1/2-null ESCs lack S1P and accumulate the precursor sphingosine. The double-mutant cells fail to grow due to a marked cell cycle arrest at G2/M. Mutant cells activate expression of telomere elongation factor genes Zscan4, Tcstv1, and Tcstv3 and display longer telomeric repeats. Adding exogenous S1P to the medium had no impact, but the cell cycle arrest is partially alleviated by the expression of a ceramide synthase 2, which converts excess sphingosine into ceramide. The results indicate that sphingosine kinase activity is essential in mouse ESCs for limiting the accumulation of sphingosine that otherwise drives cell cycle arrest.

A human embryonic stem cell reporter line for monitoring chemical-induced cardiotoxicity.

AIMS: Human embryonic stem cells (hESCs) can be used to generate scalable numbers of cardiomyocytes (CMs) for studying cardiac biology, disease modelling, drug screens, and potentially for regenerative therapies. A fluorescence-based reporter line will significantly enhance our capacities to visualize the derivation, survival, and function of hESC-derived CMs. Our goal was to develop a reporter cell line for real-time monitoring of live hESC-derived CMs. METHODS AND RESULTS: We used CRISPR/Cas9 to knock a mCherry reporter gene into the MYH6 locus of hESC lines, H1 and H9, enabling real-time monitoring of the generation of CMs. MYH6:mCherry+ cells express atrial or ventricular markers and display a range of cardiomyocyte action potential morphologies. At 20 days of differentiation, MYH6:mCherry+ cells show features characteristic of human CMs and can be used successfully to monitor drug-induced cardiotoxicity and oleic acid-induced cardiac arrhythmia. CONCLUSION: We created two MYH6:mCherry hESC reporter lines and documented the application of these lines for disease modelling relevant to cardiomyocyte biology.

Activation-Induced Cytidine Deaminase Regulates Fibroblast Growth Factor/Extracellular Signal-Regulated Kinases Signaling to Achieve the Naïve Pluripotent State During Reprogramming.

Induced pluripotent stem cells (iPSCs) derived by in vitro reprogramming of somatic cells retain the capacity to self-renew and to differentiate into many cell types. Pluripotency encompasses multiple states, with naïve iPSCs considered as ground state, possessing high levels of self-renewal capacity and maximum potential without lineage restriction. We showed previously that activation-induced cytidine deaminase (AICDA) facilitates stabilization of pluripotency during reprogramming. Here, we report that Acida-/- iPSCs, even when successfully reprogrammed, fail to achieve the naïve pluripotent state and remain primed for differentiation because of a failure to suppress fibroblast growth factor (FGF)/extracellular signal-regulated kinases (ERK) signaling. Although the mutant cells display marked genomic hypermethylation, suppression of FGF/ERK signaling by AICDA is independent of deaminase activity. Thus, our study identifies AICDA as a novel regulator of naïve pluripotency through its activity on FGF/ERK signaling. Stem Cells 2019;37:1003-1017.

Autopsy findings of miliary tuberculosis in a renal transplant recipient.

Miliary tuberculosis is a lethal form of disseminated tuberculosis (TB), deriving its name from the millet-seed-sized granulomas in multiple organs. As TB still remains a leading cause of morbidity and mortality in India, its disseminated forms need to be diagnosed early to ensure more aggressive treatment at the earliest possible time. However, a considerable number of cases are missed ante-mortem. We discuss the case of a 32-year-old immunocompromised, non-HIV patient with an ante-mortem diagnosis of pulmonary TB. However, multiple organ involvement by Mycobacterium tuberculosis was demonstrated on autopsy. This case highlights the role of autopsy as a research and learning tool, and prudential clinico-pathologic correlation, which will improve clinical outcomes in the future.

Autopsy findings of miliary tuberculosis in a renal transplant recipient

Miliary tuberculosis is a lethal form of disseminated tuberculosis (TB), deriving its name from the millet-seed-sized granulomas in multiple organs. As TB still remains a leading cause of morbidity and mortality in India, its disseminated forms need to be diagnosed early to ensure more aggressive treatment at the earliest possible time. However, a considerable number of cases are missed ante-mortem. We discuss the case of a 32-year-old immunocompromised, non-HIV patient with an ante-mortem diagnosis of pulmonary TB. However, multiple organ involvement by was demonstrated on autopsy. This case highlights the role of autopsy as a research and learning tool, and prudential clinico-pathologic correlation, which will improve clinical outcomes in the future.

An updated methodology to review developing-country vaccine manufacturer viability.

In 1997, Milstien, Batson, and Meaney published "A Systematic Method for Evaluating the Potential Viability of Local Vaccine Producers." The paper identified characteristics of successful vaccine manufacturers and developed a viability framework to evaluate their performance. This paper revisits the original study after two decades to determine the ability of the framework to predict manufacturer success. By reconstructing much of the original dataset and conducting in-depth interviews, the authors developed informed views on the continued viability of manufacturers in low- and middle-income country markets. Considering the marked changes in the market and technology landscape since 1997, the authors find the viability framework to be predictive and a useful lens through which to evaluate manufacturer success or failure. Of particular interest is how incumbent and potentially new developing-country vaccine manufacturers enter and sustain production in competitive international markets and how they integrate (or fail to integrate) new technology into the production process. Ultimately, most manufacturers will need to meet global quality standards to be viable. As governments and donors consider investments in vaccine producers, the updated viability factors will be a useful tool in evaluating the prospects of manufacturers over the mid to long term. The paper emphasizes that while up-front investments are important, other critical factors-including investments in a national regulatory authority, manufacturer independence, and ability to adapt and adopt new technology-are necessary to ensure viability.

Genome Editing in hPSCs Reveals GATA6 Haploinsufficiency and a Genetic Interaction with GATA4 in Human Pancreatic Development.

Human disease phenotypes associated with haploinsufficient gene requirements are often not recapitulated well in animal models. Here, we have investigated the association between human GATA6 haploinsufficiency and a wide range of clinical phenotypes that include neonatal and adult-onset diabetes using CRISPR (clustered regularly interspaced short palindromic repeat)/Cas9-mediated genome editing coupled with human pluripotent stem cell (hPSC) directed differentiation. We found that loss of one GATA6 allele specifically affects the differentiation of human pancreatic progenitors from the early PDX1+ stage to the more mature PDX1+NKX6.1+ stage, leading to impaired formation of glucose-responsive ß-like cells. In addition to this GATA6 haploinsufficiency, we also identified dosage-sensitive requirements for GATA6 and GATA4 in the formation of both definitive endoderm and pancreatic progenitor cells. Our work expands the application of hPSCs from studying the impact of individual gene loci to investigation of multigenic human traits, and it establishes an approach for identifying genetic modifiers of human disease.

The challenges of introducing routine G6PD testing into radical cure: a workshop report.

The only currently available drug that effectively removes malaria hypnozoites from the human host is primaquine. The use of 8-aminoquinolines is hampered by haemolytic side effects in glucose-6-phosphate dehydrogenase (G6PD) deficient individuals. Recently a number of qualitative and a quantitative rapid diagnostic test (RDT) format have been developed that provide an alternative to the current standard G6PD activity assays. The WHO has recently recommended routine testing of G6PD status prior to primaquine radical cure whenever possible. A workshop was held in the Philippines in early 2015 to discuss key challenges and knowledge gaps that hinder the introduction of routine G6PD testing. Two point-of-care (PoC) test formats for the measurement of G6PD activity are currently available: qualitative tests comparable to malaria RDT as well as biosensors that provide a quantitative reading. Qualitative G6PD PoC tests provide a binomial test result, are easy to use and some products are comparable in price to the widely used fluorescent spot test. Qualitative test results can accurately classify hemizygous males, heterozygous females, but may misclassify females with intermediate G6PD activity. Biosensors provide a more complex quantitative readout and are better suited to identify heterozygous females. While associated with higher costs per sample tested biosensors have the potential for broader use in other scenarios where knowledge of G6PD activity is relevant as well. The introduction of routine G6PD testing is associated with additional costs on top of routine treatment that will vary by setting and will need to be assessed prior to test introduction. Reliable G6PD PoC tests have the potential to play an essential role in future malaria elimination programmes, however require an improved understanding on how to best integrate routine G6PD testing into different health settings.

Necrotizing Fasciitis of the Abdominal Wall Caused by Serratia Marcescens.

In this article, we present the first case of necrotizing fasciitis affecting the abdominal wall caused by Serratia marcescens and share results of a focused review of S. marcescens induced necrotizing fasciitis. Our patient underwent aorto-femoral bypass grafting for advanced peripheral vascular disease and presented 3 weeks postoperatively with pain, erythema and discharge from the incision site in the left lower abdominal wall and underwent multiple debridement of the affected area. Pathology of debrided tissue indicated extensive necrosis involving the adipose tissue, fascia and skeletal muscle. Wound cultures were positive for Serratia marcescens. She was successfully treated with antibiotics and multiple surgical debridements. Since necrotizing fasciitis is a medical and surgical emergency, it is critical to examine infectivity trends, clinical characteristics in its causative spectrum. Using PubMed we found 17 published cases of necrotizing fasciitis caused by Serratia marcescens, and then analyzed patterns among those cases. Serratia marcescens is prominent in the community and hospital settings, and information on infection presentations, risk factors, characteristics, treatment, course, and complications as provided through this study can help identify cases earlier and mitigate poor outcomes. Patients with positive blood cultures and those patients where surgical intervention was not provided or delayed had a higher mortality. Surgical intervention is a definite way to establish the diagnosis of necrotizing infection and differentiate it from other entities.

Intracranial abscess due to Mycobacterium avium complex in an immunocompetent host: a case report.

BACKGROUND: Mycobacterium avium complex (MAC) is a ubiquitous pathogen, widely distributed in the environment including water, soil and animals. It is an uncommonly encountered clinical pathogen; primarily causing pulmonary infections in patients with underlying lung disease or disseminated disease in immunocompromised hosts. Sporadically, extra-pulmonary infections have been documented including involvement of the liver, spleen, skin, soft tissue and lymph nodes. Central nervous system (CNS) infections due to MAC are exceedingly rare and carry a poor prognosis. Additionally, such infections are largely reported in patients infected with HIV. Herein we report the first case of intracranial abscess due to MAC in an immunocompetent man with a normal CD4 count and negative HIV status. CASE PRESENTATION: A previously healthy 40-year-old male presented to us with progressively worsening CNS symptoms. The patient's presentation was uncharacteristic of MAC infection in immunocompetent hosts, as he developed subacute, progressive symptoms that included severe frontal headaches, left eyelid swelling, blurry vision, and diplopia, without any pulmonary or systemic manifestations. Neuroimaging revealed multiple ring-enhancing lesions, which required neurosurgical intervention. MAC was the only pathogen that grew from intraoperative tissue cultures. The patient was subsequently treated with a 12-month regimen consisting of Clarithromycin, Ethambutol, and Rifampin, with successful clinical resolution. CONCLUSION: Our findings indicate that it is important to consider rare infections such as MAC in immunocompetent patients, regardless of atypical symptoms. Despite the severity of this infection, with timely diagnosis effective treatment is available.

Multi-country analysis of treatment costs for HIV/AIDS (MATCH): facility-level ART unit cost analysis in Ethiopia, Malawi, Rwanda, South Africa and Zambia.

BACKGROUND: Today's uncertain HIV funding landscape threatens to slow progress towards treatment goals. Understanding the costs of antiretroviral therapy (ART) will be essential for governments to make informed policy decisions about the pace of scale-up under the 2013 WHO HIV Treatment Guidelines, which increase the number of people eligible for treatment from 17.6 million to 28.6 million. The study presented here is one of the largest of its kind and the first to describe the facility-level cost of ART in a random sample of facilities in Ethiopia, Malawi, Rwanda, South Africa and Zambia. METHODS & FINDINGS: In 2010-2011, comprehensive data on one year of facility-level ART costs and patient outcomes were collected from 161 facilities, selected using stratified random sampling. Overall, facility-level ART costs were significantly lower than expected in four of the five countries, with a simple average of $208 per patient-year (ppy) across Ethiopia, Malawi, Rwanda and Zambia. Costs were higher in South Africa, at $682 ppy. This included medications, laboratory services, direct and indirect personnel, patient support, equipment and administrative services. Facilities demonstrated the ability to retain patients alive and on treatment at these costs, although outcomes for established patients (2-8% annual loss to follow-up or death) were better than outcomes for new patients in their first year of ART (77-95% alive and on treatment). CONCLUSIONS: This study illustrated that the facility-level costs of ART are lower than previously understood in these five countries. While limitations must be considered, and costs will vary across countries, this suggests that expanded treatment coverage may be affordable. Further research is needed to understand investment costs of treatment scale-up, non-facility costs and opportunities for more efficient resource allocation.

Biological function of activation-induced cytidine deaminase (AID).

Activation-induced Cytidine Deaminase (AID) is an essential regulator of B cell diversification, but its full range of action has until recently been an enigma. Based on homology, it was originally proposed to be an RNA-editing enzyme, but so far, no RNA substrates are known. Rather, it functions by deaminating cytidine, and in this manner, coupled with base-excision repair or mismatch repair machinery, it is a natural mutator. This allows it to play a central role in adaptive immunity, whereby it initiates the processes of class switch recombination and somatic hypermutation to help generate a diverse and high-affinity repertoire of immunoglobulin isotypes. More recently, it has been appreciated that methylated cytidine, already known as a key epigenetic mark on DNA controlling gene expression, can also be a target for AID modification. Coupled with repair machinery, this can facilitate the active removal of methylated DNA. This activity can impact the process of cellular reprogramming, including transition of a somatic cell to pluripotency, which requires major reshuffling of epigenetic memory. Thus, seemingly disparate roles for AID in controlling immune diversity and epigenetic memory have a common mechanistic basis. However, the very activity that is so useful for B cell diversity and cellular reprogramming is dangerous for the integrity of the genome. Thus, AID expression and activity is tightly regulated, and deregulation is associated with diseases including cancer. Here, we review the range of AID functions with a focus on its mechanisms of action and regulation. Major questions remain to be answered concerning how and when AID is targeted to specific loci and how this impacts development and disease.