Wnt/β-Catenin Signaling Pathway Is Necessary for the Specification but Not the Maintenance of the Mouse Retinal Pigment Epithelium.

β-Catenin (Ctnnb1) has been shown to play critical roles in the development and maintenance of epithelial cells, including the retinal pigment epithelium (RPE). Ctnnb1 is not only a component of intercellular junctions in the epithelium, it also functions as a transcriptional regulator in the Wnt signaling pathway. To identify which of its functional modalities is critically involved in mouse RPE development and maintenance, we varied gene content and activity in mouse RPE lineage cells and tested their impacts on mouse eye development.

mTORC1-induced retinal progenitor cell overproliferation leads to accelerated mitotic aging and degeneration of descendent Müller glia.

Retinal progenitor cells (RPCs) divide in limited numbers to generate the cells comprising vertebrate retina. The molecular mechanism that leads RPC to the division limit, however, remains elusive. Here, we find that the hyperactivation of mechanistic target of rapamycin complex 1 (mTORC1) in an RPC subset by deletion of () makes the RPCs arrive at the division limit precociously and produce Müller glia (MG) that degenerate from senescence-associated cell death.

Retinoid Metabolism in the Degeneration of Pten-Deficient Mouse Retinal Pigment Epithelium.

In vertebrate eyes, the retinal pigment epithelium (RPE) provides structural and functional homeostasis to the retina. The RPE takes up retinol (ROL) to be dehydrogenated and isomerized to 11--retinaldehyde (11--RAL), which is a functional photopigment in mammalian photoreceptors. As excessive ROL is toxic, the RPE must also establish mechanisms to protect against ROL toxicity.

A 9-Year Comparison of Dementia Prevalence in Korea: Results of NaSDEK 2008 and 2017.

Background: In many high-income Western countries, the prevalence of dementia had been reduced over the past decades.

Objective: We investigated whether the prevalence of all-cause dementia, Alzheimer's disease, vascular dementia, and mild cognitive impairment (MCI) had changed in Korea from 2008 to 2017.

Methods: Nationwide Survey on Dementia Epidemiology of Korea (NaSDEK) in 2008 and 2017 was conducted on representative elderly populations that were randomly sampled across South Korea.

A Systematic Review and Meta-Analysis of Nonpharmacological Interventions for Moderate to Severe Dementia.

Objective: Due to limited efficacy of medications, non-pharmacological interventions (NPI) are frequently co-administered to people with moderate to severe dementia (PWMSD). This systematic review and meta-analysis investigated the effects of NPI on activities of daily living (ADL), behavioral and psychological symptoms of dementia (BPSD), and cognition and quality of life (QoL) of PWMSD.

Methods: A literature search was conducted in the following databases: Cochrane CENTRAL, EMBASE, Medline, CIHNAL, PsycINFO, KoreaMED, KMbase, and KISS.

A Systematic Review of Nonpharmacological Interventions for Moderate to Severe Dementia: A Study Protocol for a Systematic Review and Meta-Analysis.

The study is designed as a systematic review on nonpharmacological interventions for patients with moderate to severe dementia. This review will be conducted in accordance with the Cochrane Handbook for Systematic Reviews of Interventions. The following databases will be searched: Cochrane CENTRAL, MEDLINE, EMBASE, CINAHL, PsycINFO, KoreaMED, KMbase, and KISS.

Cognitive Stimulation as a Therapeutic Modality for Dementia: A Meta-Analysis.

Objective: Although cognitive stimulation (CS) is one of the most popular non-pharmacological interventions for people with dementia, its efficacy is still debatable. We performed a meta-analysis of randomized controlled trials (RCTs) on the efficacy of CS in people with dementia.

Methods: Data sources were identified by searching PubMed, MEDLINE, Embase, psychINFO, and Cochrane Reviews Library.

Prevalence Rates of Dementia and Mild Cognitive Impairment Are Affected by the Diagnostic Parameter Changes for Neurocognitive Disorders in the DSM-5 in a Korean Population.

Aim: To examine the impact of the revised diagnostic criteria for neurocognitive disorders (NCDs) in the Diagnostic and Statistical Manual of Mental Disorders, 5th edition (DSM-5) on the prevalence of dementia and mild cognitive impairment (MCI).

Methods: A total of 755 participants aged 65 years or older in the Nationwide Survey on Dementia Epidemiology in Korea 2012 were rediagnosed according to the DSM-5 criteria.

Results: The estimated age-, gender-, education-, and urbanicity-standardized prevalence rates of major and mild NCDs were 8.

An International Comparative Study on Driving Regulations on People with Dementia.

Over 40% of people with dementia drive, with a two to five times greater accident risk than controls. This has fueled public concerns about the risk of traffic accidents by drivers with dementia (DWD). We compared driving regulations on seniors and DWD between ten European and Asia-Pacific countries to identify key implications for national strategies.

Incidence of and risk factors for Alzheimer's disease and mild cognitive impairment in Korean elderly.

Background/aims: Knowledge of incidence rates and risk factors is essential for the development of strategies to treat patients with Alzheimer's disease (AD) and mild cognitive impairment (MCI).

Methods: A subpopulation of the Nationwide Survey on Dementia Epidemiology (460 Korean subjects aged ≥65 years from 2 rural and 2 urban districts) was followed up for 3.5 years.

Prevalence and trends of dementia in Korea: a systematic review and meta-analysis.

Through a systematic review and meta-analysis of epidemiological studies on dementia, we assessed the prevalence of dementia and its subtypes-Alzheimer' disease (AD) and vascular dementia (VaD)-in Korea. We searched for epidemiological studies on dementia published in 1990-2013 using PubMed, Scopus, EMBASE, KoreaMed, KISS, and RiCH. Dementia prevalence in elderly patients (aged≥65 yr) was 9.

Association between measures of obesity and colorectal adenoma.

Background: Few studies have used body mass index (BMI), waist-to-hip ratio (WHR) and waist circumference (WC) at the same time to investigate the association between obesity and colorectal adenoma. This study examined the strength of association between colorectal adenoma and obesity using not only BMI, but also WHR and WC.

Methods: Subjects of this study included 1322 asymptomatic patients who underwent colonoscopy for cancer screening from January 2006 to June 2008.

Zinc increases the phagocytic capacity of canine peripheral blood phagocytes in vitro.

Zinc is a trace element that plays a central role in the immune system. In the present study, the effect of zinc on the phagocytic capacity of canine peripheral blood phagocytes was examined in vitro by flow cytometry. Zinc was used at a concentration of 100 microM, which preserved cell viability.

Neuroprotective effects of human mesenchymal stem cells on dopaminergic neurons through anti-inflammatory action.

Parkinson's disease (PD) is a common, progressive neurodegenerative disorder caused by the loss of dopaminergic neurons in the substantia nigra (SN). Numerous studies have provided evidence suggesting that neuroinflammation plays an important role in the pathogenesis of PD. In this study, we used lipopolysaccharide (LPS)-induced in vitro and in vivo inflammation models to investigate whether human mesenchymal stem cells (hMSCs) have a protective effect on the dopaminergic system through anti-inflammatory mechanisms.

Prevalence of irritable bowel syndrome, influence of lifestyle factors and bowel habits in Korean college students.

Background And Aims: Irritable bowel syndrome (IBS) is considered to be prevalent in the general population, but there are little data on bowel habits and IBS in Korea. Because nurses are frequently called on to help this patient population with IBS and help manage their symptoms, it is very necessary to get some practical information about patients' experiences and to outline a multifaceted approach to the practical management of patient with IBS. So this study aims to describe the bowel habits and the prevalence of IBS in young university students in Korea and to investigate the influence of lifestyle factors, including dietary habits, on IBS prevalence.

[Effect of Helicobacter pylori on gastric epithelial cell kinetics and expression of apoptosis-related proteins in gastric carcinogenesis].

Background/aims: We investigated apoptosis, cell proliferation and the expression of apoptosis-related proteins in the gastric epithelial cells of Helicobacter pylori (H. pylori)-negative and positive patients.

Methods: TUNEL staining, immunohistochemical staining for Ki-67, p53, Bcl-2, Bcl-X(L) and Bax were performed on paraffin-embedded specimens obtained from 11 H.