Engineered Cas12i2 is a versatile high-efficiency platform for therapeutic genome editing.

The CRISPR-Cas type V-I is a family of Cas12i-containing programmable nuclease systems guided by a short crRNA without requirement for a tracrRNA. Here we present an engineered Type V-I CRISPR system (Cas12i), ABR-001, which utilizes a tracr-less guide RNA. The compact Cas12i effector is capable of self-processing pre-crRNA and cleaving dsDNA targets, which facilitates versatile delivery options and multiplexing, respectively.

Genome-wide CRISPR interference screen identifies long non-coding RNA loci required for differentiation and pluripotency.

Although many long non-coding RNAs (lncRNAs) exhibit lineage-specific expression, the vast majority remain functionally uncharacterized in the context of development. Here, we report the first described human embryonic stem cell (hESC) lines to repress (CRISPRi) or activate (CRISPRa) transcription during differentiation into all three germ layers, facilitating the modulation of lncRNA expression during early development. We performed an unbiased, genome-wide CRISPRi screen targeting thousands of lncRNA loci expressed during endoderm differentiation.

The SWI/SNF complex regulates the expression of miR-222, a tumor suppressor microRNA in lung adenocarcinoma.

SWitch/Sucrose Non-Fermentable (SWI/SNF) chromatin remodeling complexes are key epigenetic regulators that are recurrently mutated in cancer. Most studies of these complexes are focused on their role in regulating protein-coding genes. However, here, we show that SWI/SNF complexes control the expression of microRNAs.

TRIM71 binds to IMP1 and is capable of positive and negative regulation of target RNAs.

TRIM71 is an important RNA-binding protein in development and disease, yet its direct targets have not been investigated globally. Here we describe a number of disease and developmentally-relevant TRIM71 RNA targets such as the family, , and . We describe a new role for TRIM71 as capable of positive or negative RNA regulation depending on the RNA target.

Author Correction: BRD9 defines a SWI/SNF sub-complex and constitutes a specific vulnerability in malignant rhabdoid tumors.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

BRD9 defines a SWI/SNF sub-complex and constitutes a specific vulnerability in malignant rhabdoid tumors.

Bromodomain-containing protein 9 (BRD9) is a recently identified subunit of SWI/SNF(BAF) chromatin remodeling complexes, yet its function is poorly understood. Here, using a genome-wide CRISPR-Cas9 screen, we show that BRD9 is a specific vulnerability in pediatric malignant rhabdoid tumors (RTs), which are driven by inactivation of the SMARCB1 subunit of SWI/SNF. We find that BRD9 exists in a unique SWI/SNF sub-complex that lacks SMARCB1, which has been considered a core subunit.

Myelin modifications after chronic sleep loss in adolescent mice.

Study Objectives: Previous studies found that sleep loss can suppress the expression of genes implicated in myelination and can have adverse effects on oligodendrocyte precursor cells. On the other hand, sleep may favor myelination by promoting the expression of genes involved in its formation and maintenance. Albeit limited, these results suggest that sleep loss can have detrimental effects on the formation and maintenance of myelin.

The SWI/SNF chromatin remodelling complex is required for maintenance of lineage specific enhancers.

Genes encoding subunits of SWI/SNF (BAF) chromatin remodelling complexes are collectively altered in over 20% of human malignancies, but the mechanisms by which these complexes alter chromatin to modulate transcription and cell fate are poorly understood. Utilizing mouse embryonic fibroblast and cancer cell line models, here we show via ChIP-seq and biochemical assays that SWI/SNF complexes are preferentially targeted to distal lineage specific enhancers and interact with p300 to modulate histone H3 lysine 27 acetylation. We identify a greater requirement for SWI/SNF at typical enhancers than at most super-enhancers and at enhancers in untranscribed regions than in transcribed regions.

Subxiphoid Exchange of HeartMate II Left Ventricular Assist Device.

With increasing use of left ventricular assist devices (LVADs) for long-term circulatory support comes a growing need for device exchange. The conventional surgical approach for device exchanges has been a reoperative median resternotomy. Less-invasive HeartMate II LVAD exchange via a nonmuscle-dividing subxiphoid incision as an alternative to a left subcostal incision may reduce pain burden and facilitate recovery.

SMARCB1-mediated SWI/SNF complex function is essential for enhancer regulation.

SMARCB1 (also known as SNF5, INI1, and BAF47), a core subunit of the SWI/SNF (BAF) chromatin-remodeling complex, is inactivated in nearly all pediatric rhabdoid tumors. These aggressive cancers are among the most genomically stable, suggesting an epigenetic mechanism by which SMARCB1 loss drives transformation. Here we show that, despite having indistinguishable mutational landscapes, human rhabdoid tumors exhibit distinct enhancer H3K27ac signatures, which identify remnants of differentiation programs.

Association of Perivascular Localization of Aquaporin-4 With Cognition and Alzheimer Disease in Aging Brains.

Importance: Cognitive impairment and dementia, including Alzheimer disease (AD), are common within the aging population, yet the factors that render the aging brain vulnerable to these processes are unknown. Perivascular localization of aquaporin-4 (AQP4) facilitates the clearance of interstitial solutes, including amyloid-β, through the brainwide network of perivascular pathways termed the glymphatic system, which may be compromised in the aging brain.

Objectives: To determine whether alterations in AQP4 expression or loss of perivascular AQP4 localization are features of the aging human brain and to define their association with AD pathology.

SWI/SNF-mutant cancers depend on catalytic and non-catalytic activity of EZH2.

Human cancer genome sequencing has recently revealed that genes that encode subunits of SWI/SNF chromatin remodeling complexes are frequently mutated across a wide variety of cancers, and several subunits of the complex have been shown to have bona fide tumor suppressor activity. However, whether mutations in SWI/SNF subunits result in shared dependencies is unknown. Here we show that EZH2, a catalytic subunit of the polycomb repressive complex 2 (PRC2), is essential in all tested cancer cell lines and xenografts harboring mutations of the SWI/SNF subunits ARID1A, PBRM1, and SMARCA4, which are several of the most frequently mutated SWI/SNF subunits in human cancer, but that co-occurrence of a Ras pathway mutation is correlated with abrogation of this dependence.

Direct neuronal glucose uptake heralds activity-dependent increases in cerebral metabolism.

Metabolically, the brain is a highly active organ that relies almost exclusively on glucose as its energy source. According to the astrocyte-to-neuron lactate shuttle hypothesis, glucose is taken up by astrocytes and converted to lactate, which is then oxidized by neurons. Here we show, using two-photon imaging of a near-infrared 2-deoxyglucose analogue (2DG-IR), that glucose is taken up preferentially by neurons in awake behaving mice.

Molecular pathways: SWI/SNF (BAF) complexes are frequently mutated in cancer--mechanisms and potential therapeutic insights.

SWI/SNF chromatin remodeling complexes are pleomorphic multisubunit cellular machines that utilize the energy of ATP hydrolysis to modulate chromatin structure. The complexes interact with transcription factors at promoters and enhancers to modulate gene expression and contribute to lineage specification, differentiation, and development. Initial clues to a role in tumor suppression for SWI/SNF complexes came over a decade ago when the gene encoding the SMARCB1/SNF5 core subunit was found specifically inactivated in nearly all pediatric rhabdoid tumors.

The use of capacity ratios in introductory pharmacy practice experiences.

Objective: To describe the use of capacity ratios following the assignment of introductory pharmacy practice experiences (IPPEs) to a rising third-year pharmacy (P3) class.

Methods: Practice experience availability for IPPEs was collected by means of preceptor response to requests. Following assignment of IPPEs to the rising P3 class, capacity ratios from the IPPEs available across the entire state and within each of 4 geographic zones were calculated.

Characterization of the functional domains of the SloR metalloregulatory protein in Streptococcus mutans.

Streptococcus mutans is a commensal member of the healthy plaque biofilm and the primary causative agent of dental caries. The present study is an investigation of SloR, a 25-kDa metalloregulatory protein that modulates genes responsible for S. mutans-induced cariogenesis.

Predicting trends in HIV-1 sexual transmission in sub-Saharan Africa through the Drug Resource Enhancement Against AIDS and Malnutrition model: antiretrovirals for 5 reduction of population infectivity, incidence and prevalence at the district level.

Background: The use of antiretrovirals to reduce the incidence of human immunodeficiency virus (HIV) infection has been evaluated in mathematical models as potential strategies for curtailing the epidemic. Cohort data from the Drug Resource Enhancement Against AIDS and Malnutrition (DREAM) Program was used to generate a realistic model for the HIV epidemic in sub-Saharan Africa.

Methods: Two combined stochastic models were developed: patient and epidemic models.

Extended antenatal use of triple antiretroviral therapy for prevention of mother-to-child transmission of HIV-1 correlates with favorable pregnancy outcomes.

Objective: To evaluate pregnancy outcomes in a cohort of HIV-infected women receiving triple antiretroviral therapy (ART) for prevention of mother-to-child-transmission.

Methods: A retrospective cohort study with review of records of 3273 HIV-positive women receiving prenatal care in Malawi and Mozambique from July 2005 to December 2009 was conducted in Drug Resource Enhancement Against AIDS and Malnutrition (DREAM) centers. Patients were offered nevirapine-based triple ART initiated in pregnancy until 6 months postpartum.

Limited risk of drug resistance after discontinuation of antiretroviral prophylaxis for the prevention of breastfeeding transmission of HIV.

We evaluated 70 HIV-infected pregnant women with CD4⁺ cell count >350 cells per cubic millimeter who received zidovudine, lamivudine, and nevirapine from week 25 of gestation until 6 months after delivery and a 3-week tail of zidovudine and lamivudine at the moment of drug discontinuation. Forty days after the interruption of all drugs resistance mutations were present in 5 of 70 (7.1%) women.

Extended antenatal antiretroviral use correlates with improved infant outcomes throughout the first year of life.

Objectives: To evaluate the effect of extended antenatal triple antiretroviral therapy (ART) on infant outcomes.

Design: Retrospective cohort study using pooled data from health clinics in Malawi and Mozambique from July 2005 to December 2009.

Methods: Computerized records of 3273 HIV-infected pregnant women accessing Drug Resource Enhancement Against AIDS and Malnutrition centers were reviewed.

A cecal diaphragm associated with the use of nonsteroidal anti-inflammatory drugs.

In the small intestine, strictures and diaphragms causing obstructive symptoms are well known to occur in patients using nonsteroidal anti-inflammatory drugs. Recently, two cases of nonsteroidal anti-inflammatory drug (NSAID)-associated diaphragm-like colonic stricture were reported as unexpected findings in patients being investigated for iron-deficiency anemia. We present a third such case that occurred in the cecum in a 49-year-old woman with rheumatoid arthritis who had been taking NSAIDs for 5 years.