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Visualizing the Spatial Relationship of the Genome with the Nuclear Envelope Using Fluorescence In Situ Hybridization
The genome has a special relationship with the nuclear envelope in cells. Much of the genome is anchored at the nuclear periphery, tethered by chromatin binding proteins such nuclear lamins and other integral membrane proteins. Even though there are global assays such as DAM-ID or ChIP to assess what parts of the genome are associated with the nuclear envelope, it is also essential to be able to visualize regions of the genome in order to reveal their individual relationships with nuclear structures in single cells. This is executed by fluorescence in situ hybridization (FISH) in 2-dimensional flattened nuclei (2D-FISH) or 3-dimensionally preserved cells (3D-FISH) in combination with indirect immunofluorescence to reveal structural proteins. This chapter explains the protocols for 2D- and 3D-FISH in combination with indirect immunofluorescence and discusses options for image capture and analysis. Due to the nuclear envelope proteins being part of the non-extractable nucleoskeleton, we also describe how to prepare DNA halos through salt extraction and how they can be used to study genome behavior and association when combined with 2D-FISH.SPARKs children’s charity for funding CSC; Brunel University London Progeria Research Fund; The Gordon Memorial Trust; EURO-laminopathies consortium FP6
Elemental analysis of lung tissue particles and intracellular iron content of alveolar macrophages in pulmonary alveolar proteinosis
<p>Abstract</p> <p>Background</p> <p>Pulmonary alveolar proteinosis (PAP) is a rare disease occurred by idiopathic (autoimmune) or secondary to particle inhalation. The in-air microparticle induced X-ray emission (in-air micro-PIXE) system performs elemental analysis of materials by irradiation with a proton microbeam, and allows visualization of the spatial distribution and quantitation of various elements with very low background noise. The aim of this study was to assess the secondary PAP due to inhalation of harmful particles by employing in-air micro-PIXE analysis for particles and intracellular iron in parafin-embedded lung tissue specimens obtained from a PAP patient comparing with normal lung tissue from a non-PAP patient. The iron inside alveolar macrophages was stained with Berlin blue, and its distribution was compared with that on micro-PIXE images.</p> <p>Results</p> <p>The elements composing particles and their locations in the PAP specimens could be identified by in-air micro-PIXE analysis, with magnesium (Mg), aluminum (Al), silicon (Si), phosphorus (P), sulfur (S), scandium (Sc), potassium (K), calcium (Ca), titanium (Ti), chromium (Cr), copper (Cu), manganase (Mn), iron (Fe), and zinc (Zn) being detected. Si was the major component of the particles. Serial sections stained by Berlin blue revealed accumulation of sideromacrophages that had phagocytosed the particles. The intracellular iron content of alveolar macrophage from the surfactant-rich area in PAP was higher than normal lung tissue in control lung by both in-air micro-PIXE analysis and Berlin blue staining.</p> <p>Conclusion</p> <p>The present study demonstrated the efficacy of in-air micro-PIXE for analyzing the distribution and composition of lung particles. The intracellular iron content of single cells was determined by simultaneous two-dimensional and elemental analysis of paraffin-embedded lung tissue sections. The results suggest that secondary PAP is associated with exposure to inhaled particles and accumulation of iron in alveolar macrophages.</p
Sexual Phenotype Differences in zic2 mRNA Abundance in the Preoptic Area of a Protogynous Teleost, Thalassoma bifasciatum
The highly conserved members of the zic family of zinc-finger transcription factors are primarily known for their roles in embryonic signaling pathways and regulation of cellular proliferation and differentiation. This study describes sexual phenotype differences in abundances of zic2 mRNA in the preoptic area of the hypothalamus, a region strongly implicated in sexual behavior and function, in an adult teleost, Thalassoma bifasciatum. The bluehead wrasse (Thalassoma bifasciatum) is a valuable model for studying neuroendocrine processes because it displays two discrete male phenotypes, initial phase (IP) males and territorial, terminal phase (TP) males, and undergoes socially-controlled protogynous sex change. Previously generated microarray-based comparisons suggested that zic2 was upregulated in the brains of terminal phase males relative to initial phase males. To further explore this difference, we cloned a 727 bp sequence for neural zic2 from field-collected animals. Riboprobe-based in situ hybridization was employed to localize zic2 signal in adult bluehead brains and assess the relative abundance of brain zic2 mRNA across sexual phenotypes. We found zic2 mRNA expression was extremely abundant in the granular cells of the cerebellum and widespread in other brain regions including in the thalamus, hypothalamus, habenula, torus semicircularis, torus longitudinalis, medial longitudinal fascicle and telencephalic areas. Quantitative autoradiography and phosphorimaging showed zic2 mRNA hybridization signal in the preoptic area of the hypothalamus was significantly higher in terminal phase males relative to both initial phase males and females, and silver grain analysis confirmed this relationship between phenotypes. No significant difference in abundance was found in zic2 signal across phenotypes in the habenula, a brain region not implicated in the control of sexual behavior, or cerebellum
Demographic and circumstantial accounts of burn mortality in Cape Town, South Africa, 2001-2004: An observational register based study
<p>Abstract</p> <p>Background</p> <p>Burns are a persisting public health problem in low- and middle-income countries; however, epidemiologic data for these settings is scarce. South Africa is no exception although there is an emerging knowledge base, especially for paediatric burns. The current study describes the epidemiology of burn mortality across the lifespan in Cape Town (2.9 million inhabitants in 2001), one of the six South African metropolitan centres.</p> <p>Methods</p> <p>The distribution of burn mortality across socio-demographic groups and also their circumstances of occurrence were investigated using four year (2001 to 2004) surveillance data from the National Injury Mortality Surveillance System (n = 1024 cases).</p> <p>Results</p> <p>Burn mortality occurred at a rate of 7.9 per 100 000 person-years (95% CI: 7.3-8.3). Males sustained fatal rates 2.2 times more than that for females (p < 0.001), with rates significantly higher in the 25 to 38 and 39 to 50 age groups than at other ages (p < 0.001). The greatest difference between male and female deaths was observed in the 25 to 38 year age group, when almost three male deaths occurred for every female one. The vast majority of fatal burns were registered as accidental and occurred in the home, either over the cold and wet months or during recreational periods over weekends and across the year. Alcohol intoxication was reported for the majority of those adults whose alcohol blood levels were tested (i.e. 52.6% of cases aged 16+ years).</p> <p>Conclusion</p> <p>Besides paediatric burns, the high prevalence and circumstances of occurrence of burns among middle age men are a source of concern. There are reasons to believe that this over-representation is a reflection of detrimental living conditions, life-style and poor socio-economic status. It is recommended that there be greater prioritisation of prevention activities that involve the control or management of kerosene heat sources, the provision of alternatives to flammable housing materials, and the implementation of strategies to reduce harmful drinking practices.</p
Hypertension and type 2 diabetes: What family physicians can do to improve control of blood pressure - an observational study
Background: The prevalence of type 2 diabetes is rising, and most of these patients also have hypertension,
substantially increasing the risk of cardiovascular morbidity and mortality. The majority of these patients do not
reach target blood pressure levels for a wide variety of reasons. When a literature review provided no clear focus
for action when patients are not at target, we initiated a study to identify characteristics of patients and providers
associated with achieving target BP levels in community-based practice.
Methods: We conducted a practice- based, cross-sectional observational and mailed survey study. The setting was
the practices of 27 family physicians and nurse practitioners in 3 eastern provinces in Canada. The participants
were all patients with type 2 diabetes who could understand English, were able to give consent, and would be
available for follow-up for more than one year. Data were collected from each patient’s medical record and from
each patient and physician/nurse practitioner by mailed survey. Our main outcome measures were overall blood
pressure at target (< 130/80), systolic blood pressure at target, and diastolic blood pressure at target. Analysis
included initial descriptive statistics, logistic regression models, and multivariate regression using hierarchical
nonlinear modeling (HNLM).
Results: Fifty-four percent were at target for both systolic and diastolic pressures. Sixty-two percent were at systolic
target, and 79% were at diastolic target. Patients who reported eating food low in salt had higher odds of
reaching target blood pressure. Similarly, patients reporting low adherence to their medication regimen had lower
odds of reaching target blood pressure.
Conclusions: When primary care health professionals are dealing with blood pressures above target in a patient
with type 2 diabetes, they should pay particular attention to two factors. They should inquire about dietary salt
intake, strongly emphasize the importance of reduction, and refer for detailed counseling if necessary. Similarly,
they should inquire about adherence to the medication regimen, and employ a variety of patient-oriented
strategies to improve adherence
Polygenic risk modeling for prediction of epithelial ovarian cancer risk
Polygenic risk scores (PRS) for epithelial ovarian cancer (EOC) have the potential to improve risk stratification. Joint estimation of Single Nucleotide Polymorphism (SNP) effects in models could improve predictive performance over standard approaches of PRS construction. Here, we implemented computationally efficient, penalized, logistic regression models (lasso, elastic net, stepwise) to individual level genotype data and a Bayesian framework with continuous shrinkage, "select and shrink for summary statistics" (S4), to summary level data for epithelial non-mucinous ovarian cancer risk prediction. We developed the models in a dataset consisting of 23,564 non-mucinous EOC cases and 40,138 controls participating in the Ovarian Cancer Association Consortium (OCAC) and validated the best models in three populations of different ancestries: prospective data from 198,101 women of European ancestries; 7,669 women of East Asian ancestries; 1,072 women of African ancestries, and in 18,915 BRCA1 and 12,337 BRCA2 pathogenic variant carriers of European ancestries. In the external validation data, the model with the strongest association for non-mucinous EOC risk derived from the OCAC model development data was the S4 model (27,240 SNPs) with odds ratios (OR) of 1.38 (95% CI: 1.28-1.48, AUC: 0.588) per unit standard deviation, in women of European ancestries; 1.14 (95% CI: 1.08-1.19, AUC: 0.538) in women of East Asian ancestries; 1.38 (95% CI: 1.21-1.58, AUC: 0.593) in women of African ancestries; hazard ratios of 1.36 (95% CI: 1.29-1.43, AUC: 0.592) in BRCA1 pathogenic variant carriers and 1.49 (95% CI: 1.35-1.64, AUC: 0.624) in BRCA2 pathogenic variant carriers. Incorporation of the S4 PRS in risk prediction models for ovarian cancer may have clinical utility in ovarian cancer prevention programs
The cancer genome atlas comprehensive molecular characterization of renal cell carcinoma
Renal cell carcinoma (RCC) is not a single disease, but several histologically defined cancers with different genetic drivers, clinical courses, and therapeutic responses. The current study evaluated 843 RCC from the three major histologic subtypes, including 488 clear cell RCC, 274 papillary RCC, and 81 chromophobe RCC. Comprehensive genomic and phenotypic analysis of the RCC subtypes reveals distinctive features of each subtype that provide the foundation for the development of subtype-specific therapeutic and management strategies for patients affected with these cancers. Somatic alteration of BAP1, PBRM1, and PTEN and altered metabolic pathways correlated with subtype-specific decreased survival, while CDKN2A alteration, increased DNA hypermethylation, and increases in the immune-related Th2 gene expression signature correlated with decreased survival within all major histologic subtypes. CIMP-RCC demonstrated an increased immune signature, and a uniform and distinct metabolic expression pattern identified a subset of metabolically divergent (MD) ChRCC that associated with extremely poor survival
Comprehensive molecular characterization of the hippo signaling pathway in cancer
Hippo signaling has been recognized as a key tumor suppressor pathway. Here, we perform a comprehensive molecular characterization of 19 Hippo core genes in 9,125 tumor samples across 33 cancer types using multidimensional “omic” data from The Cancer Genome Atlas. We identify somatic drivers among Hippo genes and the related microRNA (miRNA) regulators, and using functional genomic approaches, we experimentally characterize YAP and TAZ mutation effects and miR-590 and miR-200a regulation for TAZ. Hippo pathway activity is best characterized by a YAP/TAZ transcriptional target signature of 22 genes, which shows robust prognostic power across cancer types. Our elastic-net integrated modeling further reveals cancer-type-specific pathway regulators and associated cancer drivers. Our results highlight the importance of Hippo signaling in squamous cell cancers, characterized by frequent amplification of YAP/TAZ, high expression heterogeneity, and significant prognostic patterns. This study represents a systems-biology approach to characterizing key cancer signaling pathways in the post-genomic era
The everyday experience of living with and managing a neurological condition (the LINC study): study design
Background: The impact of neurological conditions on individuals, families and society is increasing and having a
significant economic impact in Canada. While some economic data is known, the human costs of living with a
neurological condition are poorly understood and rarely factored into future burden analyses. The “Living with the
Impact of a Neurological Condition (LINC)” study aims to fill this gap. It seeks to understand, for children and adults with neurological conditions, the supports and resources that make everyday life possible and meaningful.
Methods/design: The LINC study is a nested study using mixed methods. We are interested in the following
outcomes specifically: health status; resource utilization; self-management strategies; and participation. Three studies
captured data from multiple sources, in multiple ways and from multiple perspectives. Study One: a populationbased
survey of adults (n = 1500), aged 17 and over and parents (n = 200) of children aged 5 to 16 with a neurological condition. Study Two: a prospective cohort study of 140 adults and parents carried out using monthly telephone calls for 10 months; and Study Three: a multiple perspective case study (MPCS) of 12 adults and 6
parents of children with a neurological condition. For those individuals who participate in the MPCS, we will have
data from all three studies giving us rich, in depth insights into their daily lives and how they cope with barriers to living in meaningful ways.
Discussion: The LINC study will collect, for the first time in Canada, data that reflects the impact of living with a
neurological condition from the perspectives of the individuals themselves. A variety of tools will be used in a
combination, which is unique and innovative. This study will highlight the commonalities of burden that Canadians
living with neurological conditions experience as well as their strategies for managing everyday life
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