(1,25-D 3 ), is inhibition of cell growth and induction of cell differentiation and/or apoptosis. Synthesis and degradation of the secosteroid occurs not only in the kidney but also in normal tissue or malignant extrarenal tissues such as the colon. Because 25-hydroxyvitamin D 3 24-hydroxylase (CYP24A1) is considered to be the main enzyme determining the biological half-life of 1,25-D 3 , we have examined expression of the CYP24A1 mRNA (by real-time RT-PCR) and protein (by immunohistochemistry) in normal human colon mucosa, colorectal adenomas, and adenocarcinomas in 111 patients. Although 76% of the normal and benign colonic tissue was either completely devoid of or expressed very low levels of CYP24A1, in the majority of the adenocarcinomas (69%), the enzyme was present at high concentrations. A parallel increased expression of the proliferation marker Ki-67 in the same samples suggests that overexpression of CYP24A1 reduced local 1,25-D 3 availability, decreasing its antiproliferative effect. (J Histochem Cytochem 58:277-285, 2010) COLORECTAL CANCER (CRC) is the second leading cause of malignant mortality in Western industrialized countries (Boyle and Ferlay 2005). Geographical distribution of cancer mortality in the US correlates with exposure to solar (ultraviolet B) radiation; the highest mortality rates for CRC were observed in regions with less solar radiation (Freedman et al. 2002). Furthermore, epidemiological data have shown an inverse association of serum 25-hydroxyvitamin D 3 (25-D 3 ) levels with risk for prostate, breast, and colorectal malignancies (Garland et al. 1989;Ahonen et al. 2000;Bertone-Johnson et al. 2005). Estimating premature cancer mortality in the US, Grant and Garland (2006) implied that actually 20-30% of CRC cases could be avoided by sufficient exposure to sunlight.A recent meta-analysis of 18 cohort and case-control studies showed that an elevation of serum 25-D 3 concentration to levels $33 ng/ml led to a 50% lower incidence of CRC (Gorham et al. 2005). Cumulative epidemiological evidence suggests that there is a direct correlation between reduced CRC incidence and sunlight exposure, nutritional vitamin D intake, and high serum levels of 25-D 3 (Giovannucci et al. 2006).Vitamin D metabolism is a strictly regulated, multistep process, beginning with the formation of previtamin D 3 in the skin, mediated by ultraviolet radiation, or with absorption of vitamin D from dietary sources (Henry 1997;Sawada et al. 2000;Cheng et al. 2003). Vitamin D is hydroxylated by CYP27A1 to 25-hydroxyvitamin D 3 in the liver. The last step of the activation is accomplished by the 25-hydroxyvitamin D 3 1a hydroxylase (CYP27B1) in the kidney. The most active metabolite of vitamin D 3, 1a,25-dyhydroxyvitamin D 3 (1,25-D 3 , also known as calcitriol), has a crucial Correspondence to: Enikö Kállay,
Cognitive impairment and dementia are major medical, social, and economic public health issues worldwide with significant implications for life quality in older adults. The leading causes are Alzheimer’s disease (AD) and vascular cognitive impairment/dementia (VCID). In both conditions, pathological alterations of the cerebral microcirculation play a critical pathogenic role. Currently, the main pathological biomarkers of AD—β-amyloid peptide and hyperphosphorylated tau proteins—are detected either through cerebrospinal fluid (CSF) or PET examination. Nevertheless, given that they are invasive and expensive procedures, their availability is limited. Being part of the central nervous system, the retina offers a unique and easy method to study both neurodegenerative disorders and cerebral small vessel diseases in vivo. Over the past few decades, a number of novel approaches in retinal imaging have been developed that may allow physicians and researchers to gain insights into the genesis and progression of cerebromicrovascular pathologies. Optical coherence tomography (OCT), OCT angiography, fundus photography, and dynamic vessel analyzer (DVA) are new imaging methods providing quantitative assessment of retinal structural and vascular indicators—such as thickness of the inner retinal layers, retinal vessel density, foveal avascular zone area, tortuosity and fractal dimension of retinal vessels, and microvascular dysfunction—for cognitive impairment and dementia. Should further studies need to be conducted, these retinal alterations may prove to be useful biomarkers for screening and monitoring dementia progression in clinical routine. In this review, we seek to highlight recent findings and current knowledge regarding the application of retinal biomarkers in dementia assessment.
Background: Epidemiological studies suggested the chemopreventive role of higher calcium intake in colorectal carcinogenesis. We examined genetic polymorphisms that might influence calcium metabolism: lactase (LCT) gene 13910 C/T polymorphism causing lactose intolerance and calcium-sensing receptor (CaSR) gene A986S polymorphism as a responsible factor for the altered cellular calcium sensation.
BackgroundBreast, colorectal, ovarian, and endometrial cancers constitute approximately 30% of newly diagnosed cancer cases in Switzerland, affecting more than 12,000 individuals annually. Hundreds of these patients are likely to carry germline pathogenic variants associated with hereditary breast ovarian cancer (HBOC) or Lynch syndrome (LS). Genetic services (counseling and testing) for hereditary susceptibility to cancer can prevent many cancer diagnoses and deaths through early identification and risk management.ObjectiveCascade screening is the systematic identification and testing of relatives of a known mutation carrier. It determines whether asymptomatic relatives also carry the known variant, needing management options to reduce future harmful outcomes. Specific aims of the CASCADE study are to (1) survey index cases with HBOC or LS from clinic-based genetic testing records and determine their current cancer status and surveillance practices, needs for coordination of medical care, psychosocial needs, patient-provider and patient-family communication, quality of life, and willingness to serve as advocates for cancer genetic services to blood relatives, (2) survey first- and second-degree relatives and first-cousins identified from pedigrees or family history records of HBOC and LS index cases and determine their current cancer and mutation status, cancer surveillance practices, needs for coordination of medical care, barriers and facilitators to using cancer genetic services, psychosocial needs, patient-provider and patient-family communication, quality of life, and willingness to participate in a study designed to increase use of cancer genetic services, and (3) explore the influence of patient-provider communication about genetic cancer risk on patient-family communication and the acceptability of a family-based communication, coping, and decision support intervention with focus group(s) of mutation carriers and relatives.MethodsCASCADE is a longitudinal study using surveys (online or paper/pencil) and focus groups, designed to elicit factors that enhance cascade genetic testing for HBOC and LS in Switzerland. Repeated observations are the optimal way for assessing these outcomes. Focus groups will examine barriers in patient-provider and patient-family communication, and the acceptability of a family-based communication, coping, and decision-support intervention. The survey will be developed in English, translated into three languages (German, French, and Italian), and back-translated into English, except for scales with validated versions in these languages.ResultsDescriptive analyses will include calculating means, standard deviations, frequencies, and percentages of variables and participant descriptors. Bivariate analyses (Pearson correlations, chi-square test for differences in proportions, and t test for differences in means) will assess associations between demographics and clinical characteristics. Regression analyses will incorporate generalized estimating equations for pairing index cases wit...
Diabetes mellitus itself and the severity of DR affect CT significantly, even after adjusting for the effects of confounding systemic factors. Disease duration seems to be associated with a reduction of choroidal thickness. Decreased CT proved to be correlated with the severity of DR.
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