COVID-19 pandemic in long-term care: An international perspective for policy considerations.

This paper identifies key factors rooted in the systemic failings of the long-term care sector amongst four high income countries during the COVID-19 pandemic. The goal is to offer practice and policy solutions to prevent future tragedies. Based on data from Australia, Canada, Spain and the United States, the findings support evidence-based recommendations at macro, meso and micro levels of practice and policy intervention.

Operationalizing an academic pediatric practice during the COVID-19 crisis.

We report on innovating protocols at an Academic Pediatric practice during the COVID-19 (2019 novel coronavirus) crisis. Facing the challenges of limited personal protective equipment and testing capacity, we rapidly and efficiently changed processes to optimize infection control, providing safe and effective care for our vulnerable population.

Exposure and Use of Mobile Media Devices by Young Children.

Background And Objectives: Research on children's use of mobile media devices lags behind its adoption. The objective of this study was to examine young children's exposure to and use of mobile media devices.

Methods: Cross-sectional study of 350 children aged 6 months to 4 years seen October to November 2014 at a pediatric clinic in an urban, low-income, minority community.

Modeling Photo-Bleaching Kinetics to Create High Resolution Maps of Rod Rhodopsin in the Human Retina.

We introduce and describe a novel non-invasive in-vivo method for mapping local rod rhodopsin distribution in the human retina over a 30-degree field. Our approach is based on analyzing the brightening of detected lipofuscin autofluorescence within small pixel clusters in registered imaging sequences taken with a commercial 488nm confocal scanning laser ophthalmoscope (cSLO) over a 1 minute period. We modeled the kinetics of rhodopsin bleaching by applying variational optimization techniques from applied mathematics.

Immunoguided microdissection techniques.

Over the past 15 years, laser-based microdissection has improved the precision by which scientists can procure cells of interest from a heterogeneous tissue section. However, for studies that require a large amount of material (e.g.

Nonlinear gene cluster analysis with labeling for microarray gene expression data in organ development.

Background: The gene networks underlying closure of the optic fissure during vertebrate eye development are not well-understood. We use a novel clustering method based on nonlinear dimension reduction with data labeling to analyze microarray data from laser capture microdissected (LCM) cells at the site and developmental stages (days 10.5 to 12.

Expression microdissection adapted to commercial laser dissection instruments.

Laser-based microdissection facilitates the isolation of specific cell populations from clinical or animal model tissue specimens for molecular analysis. Expression microdissection (xMD) is a second-generation technology that offers considerable advantages in dissection capabilities; however, until recently the method has not been accessible to investigators. This protocol describes the adaptation of xMD to commonly used laser microdissection instruments and to a commercially available handheld laser device in order to make the technique widely available to the biomedical research community.

RedundancyMiner: De-replication of redundant GO categories in microarray and proteomics analysis.

Background: The Gene Ontology (GO) Consortium organizes genes into hierarchical categories based on biological process, molecular function and subcellular localization. Tools such as GoMiner can leverage GO to perform ontological analysis of microarray and proteomics studies, typically generating a list of significant functional categories. Two or more of the categories are often redundant, in the sense that identical or nearly-identical sets of genes map to the categories.

Association between oxidative stress and masked hypertension in a multi-ethnic population of obese children and adolescents.

Objective: To evaluate whether oxidative stress is correlated with adiposity, obesity-related metabolic abnormalities, and ambulatory blood pressure (ABP) in a multi-ethnic pediatric population.

Study Design: We conducted a prospective study enrolling 42 obese children (age, 12.8 ± 2.

Fundus autofluorescence in type 2 idiopathic macular telangiectasia: correlation with optical coherence tomography and microperimetry.

Purpose: To use multiple imaging methods to investigate patients with type 2 idiopathic macular telangiectasia (IMT) at different disease severity stages so as to characterize and categorize disease progression through the full spectrum of disease phenotypes.

Design: Observational case series.

Methods: Twelve patients with type 2 IMT (22 eyes) examined with fundus photography, angiography, optical coherence tomography imaging, fundus autofluorescence (FAF), and microperimetry testing in an institutional setting.

Expression profiling during ocular development identifies 2 Nlz genes with a critical role in optic fissure closure.

The gene networks underlying closure of the optic fissure during vertebrate eye development are poorly understood. Here, we profile global gene expression during optic fissure closure using laser capture microdissected (LCM) tissue from the margins of the fissure. From these data, we identify a unique role for the C(2)H(2) zinc finger proteins Nlz1 and Nlz2 in normal fissure closure.

Ccl2/Cx3cr1-deficient mice: an animal model for age-related macular degeneration.

Background/aims: Senescent Ccl2-/- mice develop cardinal features of human age-related macular degeneration (AMD). Loss-of-function single-nucleotide polymorphisms within CX3CR1 are associated with AMD.

Methods: We generated Ccl2-/-/Cx3cr1-/- [double-knockout (DKO)] mice and evaluated the eyes using fundoscopy routine histology, immunochemistry, biochemistry and proteomics.

Histological staining methods preparatory to laser capture microdissection significantly affect the integrity of the cellular RNA.

Background: Gene expression profiling by microarray analysis of cells enriched by laser capture microdissection (LCM) faces several technical challenges. Frozen sections yield higher quality RNA than paraffin-imbedded sections, but even with frozen sections, the staining methods used for histological identification of cells of interest could still damage the mRNA in the cells. To study the contribution of staining methods to degradation of results from gene expression profiling of LCM samples, we subjected pellets of the mouse plasma cell tumor cell line TEPC 1165 to direct RNA extraction and to parallel frozen sectioning for LCM and subsequent RNA extraction.

Tumor-associated endothelial cells display GSTP1 and RARbeta2 promoter methylation in human prostate cancer.

Background: A functional blood supply is essential for tumor growth and proliferation. However, the mechanism of blood vessel recruitment to the tumor is still poorly understood. Ideally, a thorough molecular assessment of blood vessel cells would be critical in our comprehension of this process.

Assessment of the correlation of platelet morphology with in vivo recovery and survival.

Background: There is continuing interest in the development of in vitro tests evaluating the in vivo function, recovery, and survival of platelets stored for transfusion. A recent forum concluded that no completely reliable test exists, although discoid morphology indicates a platelet's good health. We evaluated a novel device, the NAPSAC (Noninvasive Assessment of Platelet Shape and Concentration), designed to determine noninvasively the proportion of discoid platelets in a stored concentrate, as well as platelet concentration.

A model of spectral filtering to reduce photochemical damage in age-related macular degeneration.

Background/purpose: Cumulative sunlight exposure and cataract surgery are reported risk factors for advanced age-related macular degeneration (AMD). Laboratory studies suggest that accumulation and photochemical reactions of A2E (N-retinylidene-N-retinylethanolamine) and its epoxides, components of lipofuscin, are important in AMD. To relate this data to the clinical setting, we modeled the effects of macular irradiance and spectral filtering on production of A2E and reactive oxygen intermediates (ROIs) in pseudophakic eyes with a clear or "yellow" intraocular lens (IOL) and in phakic eyes.

Identification of genes expressed in primate primordial oocytes.

Background: The factors involved in oocyte survival and transition from quiescence to the growing phenotype remain unknown. Herein we report genes that are differentially expressed in the primordial oocyte revealed by DNA arrays.

Methods: Primordial oocytes were captured selectively in rhesus monkey ovary sections using laser capture microdissection.

Assessment of gene expression in head and neck carcinoma using laser capture microdissection and real-time reverse transcription polymerase chain reaction.

Objectives: To quantify gene expression in tumor cells from human head and neck squamous cell carcinomas (HNSCC) using laser capture microdissection (LCM).

Study Design: Histopathologically identified HNSCC cells were microdissected from frozen sections, RNA was isolated, and vascular endothelial growth factor (VEGF) gene expression was measured by real-time reverse transcriptase polymerase chain reaction (RT-PCR).

Materials And Methods: Two human HNSCC tumor samples and matched normal mucosal biopsies and five human xenograft tumor specimens were harvested, embedded, and frozen in OCT.

Expression microdissection: operator-independent retrieval of cells for molecular profiling.

Tissue microdissection is an important method for the study of disease states. However, it is difficult to perform high-throughput molecular analysis with current techniques. We describe here a prototype version of a novel technique (expression microdissection) that allows for the procurement of desired cells via molecular targeting.

Selective gene expression in magnocellular neurons in rat supraoptic nucleus.

Oxytocin- and vasopressin-producing magnocellular neurons (MCNs) of the hypothalamo-neurohypophysial system are the only neuronal phenotypes present in the rat supraoptic nucleus (SON). Laser microdissection of the SON, extraction and T7-based amplification of its RNAs, and analysis of the resulting cDNAs by hybridization on a 35, 319 element DNA microarray have provided a detailed composite view of the gene expression profile of the MCNs. The genes expressed in the SON were compared with those expressed in a reference tissue consisting of total hypothalamus, and this "expression ratio" indicated which genes were preferentially expressed in the SON.

Histone H2AX phosphorylation is dispensable for the initial recognition of DNA breaks.

Histone H2AX is rapidly phosphorylated in the chromatin micro-environment surrounding a DNA double-strand break (DSB). Although H2AX deficiency is not detrimental to life, H2AX is required for the accumulation of numerous essential proteins into irradiation induced foci (IRIF). However, the relationship between IRIF formation, H2AX phosphorylation (gamma-H2AX) and the detection of DNA damage is unclear.

Post-analysis follow-up and validation of microarray experiments.

Measurement of gene-expression profiles using microarray technology is becoming increasingly popular among the biomedical research community. Although there has been great progress in this field, investigators are still confronted with a difficult question after completing their experiments: how to validate the large data sets that are generated? This review summarizes current approaches to verifying global expression results, discusses the caveats that must be considered, and describes some methods that are being developed to address outstanding problems.

A comparison of hydraulic and laser capture microdissection methods for collection of single B cells, PCR, and sequencing of antibody VDJ.

During the development of B lymphocytes, a series of gene rearrangements assemble the sequences that encode immunoglobulin heavy and light chains (VDJ). Earlier studies of VDJ sequence diversification during expansion of cells in splenic or appendix germinal centers used hydraulic micromanipulation (HM) to collect single B cells for PCR amplification of rearranged antibody heavy and light chain genes. PCR products were directly sequenced without a cloning step.

A preservation method that allows recovery of intact RNA from tissues dissected by laser capture microdissection.

We report a novel method for preparing samples for laser capture microdissection. The procedure described here permits extraction of intact RNA while preserving morphology, thus being suitable both for identification of specific cells and for analysis of their gene expression. The method is applicable to both mouse embryos and human tumors and may improve the preparation of cDNA libraries from specific cell types without interfering with histological diagnosis.