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Editorial 2002; 23(Suppl 2): 79-81 PubMed PMID: 12163853 Citation  Keywords:  Animals, Humans, Light:adverse effects, Neoplasms:epidemiology, Neurosecretory Systems:physiology, Risk Factors,.   

: A conference was held at the University of Cologne on May 2-3, 2002, to discuss the strength-of-the-evidence supporting a linkage between light, endocrine systems and cancer. This overview of the conference is intended to summarize some of the key elements of the conference and to indicate both conclusions and research gaps identified by this reviewer....

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Editorial 2002; 23(Suppl 2): 71-78 PubMed PMID: 12163852 Citation  Keywords:  Darkness, Decision Making, Humans, Light:adverse effects, Neoplasms:epidemiology, Neurosecretory Systems:physiology, Risk Factors,.   

: Research on light at night and cancer is evolving at an accelerating pace, fueled largely by exciting results in rodent toxicology and basic human biology. Epidemiologic research is at a relatively early stage of development in which the exposure surrogates such as shift work and blindness predominate. Causal graphs for shift work, light at night and breast cancer illustrate some of the subtleties that can arise in the use of exposure surrogates of different kinds. Baseline data on circadian rhythms and melatonin cycles among human populations living at different latitudes are needed. Epidemiologic study of this topic is expected to mature soon as studies begin to incorporate quantitative and semiquantitative measurements and personal histories of exposure to light at night. The current emphasis on breast cancer should widen to include other cancers and intermediate outcomes. An advance in epidemiologic studies of blind persons would be to compare cancer rates between the "cortically blind" and the "retinally blind" within levels of visual impairment. Without a proposed intervention to reduce exposure to light at night, attributable fraction and attributable caseload estimates are meaningless. In the near future, both epidemiologic and laboratory research in this area are expected to grow appreciably in scope and scale....

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Journal Article 2002; 23(Suppl 2): 57-60 PubMed PMID: 12163850 Citation  Keywords:  Breast Neoplasms:epidemiology, Circadian Rhythm, Female, Humans, Light:adverse effects, Lighting, Risk Factors,.   

: Risk of breast cancer varies by about 5-fold among societies, and incidence and mortality have been increasing worldwide for many decades. Migrants from low-risk Asian societies to the U.S. suffer elevated risk of breast cancer in their own lifetimes, and the second or third generation Asian-Americans attain the high risk of the multi-generational European immigrants [1,2]. Something about a modern Western lifestyle apparently increases risk dramatically. Madigan et al. [3] estimate that 41% of the new U.S. cases of breast cancer are explained by "known risk factors"; these include the reproductive factors of age at first birth, menarche, menopause. They ascribe about 30% to reproductive factors when they are analyzed alone. "High income" is estimated to account for about 19% when analyzed by itself. The 41% is an analysis taking all the factors together, and since they are related, the total is less than the sum of estimates for the individual items. By itself, "High income" has no biological interpretation and must reflect attributes of lifestyle and/or environment that increase risk. So, the proportion of breast cancer cases in the U.S. that can be accounted for by known biological risk factors is about one third. Therefore, at least half of breast cancer risk in the U.S., and other Westernized/industrialized societies, is in excess of that found in non-industrialized societies and is without any agreed-upon explanation. Many candidate factors exist, each with a cadre of proponents. The sum of these may turn out to explain the bulk of the excess risk in modern societies. On the other hand, they may not, and worse, may fall woefully short....

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Journal Article 2002; 23(Suppl 2): 17-22 PubMed PMID: 12163843 Citation  Keywords:  Breast Neoplasms:epidemiology, Circadian Rhythm:physiology, Female, Humans, Light, Melatonin:physiology, Photoreceptor Cells, Vertebrate:physiology, Risk Factors,.   

: The impact of breast cancer on women across the world has been extensive and severe. As prevalence of breast cancer is greatest in industrialized regions, exposure to light at night has been proposed as a potential risk factor. This theory is supported by the epidemiological observations of decreased breast cancer in blind women and increased breast cancer in women who do shift-work. In addition, human, animal and in vitro studies which have investigated the melatonin-cancer dynamic indicate an apparent relationship between light, melatonin and cancer, albeit complex. Recent developments in understanding melatonin regulation by light in humans are examined, with particular attention to factors that contribute to the sensitivity of the light-induced melatonin suppression response. Specifically, the role of spectral characteristics of light is addressed, and recent relevant action spectrum studies in humans and other mammalian species are discussed. Across five action spectra for circadian and other non-visual responses, a peak sensitivity between 446-484 nm was identified. Under highly controlled exposure circumstances, less than 1 lux of monochromatic light elicited a significant suppression of nocturnal melatonin. In view of the possible link between light exposure, melatonin suppression and cancer risk, it is important to continue to identify the basic related ocular physiology. Visual performance, rather than circadian function, has been the primary focus of architectural lighting systems. It is now necessary to reevaluate lighting strategies, with consideration of circadian influences, in an effort to maximize physiological homeostasis and health....

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Journal Article 2001; 22(1): 39-44 PubMed PMID: 11335878 Citation  Keywords:  Adult, Aged, Antiviral Agents:adverse effects, Comorbidity, Female, Follow-Up Studies, Hepatitis C, Chronic:drug therapy, Humans, Incidence, Interferon-alpha:adverse effects, Male, Middle Aged, Prevalence, Retrospective Studies, Risk Factors, Sex Distribu.   

OBJECTIVES: To clarify the relationship between interferon-alpha (IFN-alpha) therapy and autoimmune thyroiditis in chronic hepatitis C virus (HCV) infection, we investigated a selected number of patients without basal thyroid dysfunctions.

MATERIALS AND METHODS: 130 patients (average age: 20-70), with chronic HCV infection and without basal clinical and laboratory signs of autoimmune thyroiditis were divided into two groups: IFN-alpha treated (A) and untreated (B) patients. Group A received IFN-alpha (three million U.I./3 times a week) for six months; group B was followed for the same period. Thyroid peroxidase and thyroglobulin autoantibodies were measured by radioimmunoassay; thyroid function was measured by radioimmunoassay (free thyroxine and triiodothyronine) and immunoradiometric assay (thyroid stimulating hormone).

RESULTS: After a 6-month period, thyroid autoantibodies positivity was documented in 21.1% of group A and in 10.3% of group B patients, both statistically relevant (p<0.001 and p<0.011, respectively). The comparison between the two groups was not statistically relevant (p=0.142).

CONCLUSIONS: Our study showed a prevalence of de novo thyroid autoimmunity in chronic HCV patients treated with IFN-alpha, confirming previous data in literature. The lack of a significant difference between treated and untreated patients strongly suggests that the anti-thyroid autoimmune response is linked to the HCV infection itself. Moreover, IFN-alpha therapy probably does not represent a risk factor in renewing the autoimmune processes of the thyroid gland. Thyroid function and autoantibodies must be systematically monitored in patients with HCV infection, especially in female and IFN-alpha treated population, not only to verify the possible thyroid abnormalities but also to rule out concomitant autoimmune diseases....

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Journal Article 2018; 39(3): 219-225 PubMed PMID: 30431736 Citation  Keywords:  Adolescent, Adult, Body Mass Index, Estradiol:blood, Female, Humans, Menstruation Disturbances:blood, Obesity:blood, Oligomenorrhea:blood, Overweight:blood, Risk Factors, Sex Hormone-Binding Globulin:metabolism, Testosterone:blood, Vitamin D:analogs & der.   

INTRODUCTION: Vitamin D (VD) plays a crucial role in calcium metabolism as well as immunological and endocrine homeostasis. Previous studies revealed strong inverse correlation between VD levels and insulin resistance, parathyroid dysfunctions and autoimmune thyroid disease. Insufficient evidence concerns its dependency of ovarian hormones. Malfunctioning of the ovaries results in menstrual disorders that are one of the most common endocrine impairments in young women of reproductive age. MATERIAL AND METHODS: The study was aimed to evaluate the correlation between 25(OH)D serum concentration and estradiol, testosterone as well as body mass index (BMI) in women with oligomenorrhea. 134 women of reproductive age with oligomenorrhea were eligible for the study. 25-hydroxyvitamin D [25(OH)D], estradiol, testosterone and sex hormone-binding globulin (SHBG) were measured using chemiluminescence immunoassay. Free androgen index (FAI) and body mass index (BMI) were calculated. RESULTS: Critical 25(OH)D deficiency (<10 ng/ml) was found in 13.4% of women, the risk of deficiency (<30 mg/dl) was diagnosed in 69.4%, while sufficient level of VD (>30 mg/ml) in 17.2% of them. Significant negative correlation was detected between 25(OH)D and estradiol serum concentrations (r=-0.2; p=0.049), as well as BMI levels (r=-0.22; p=0.01). However, no significant correlation was found between 25(OH)D and testosterone (r=-017; p=0.055), SHBG (r=0.08; p=0.4) and FAI (r=-0.1; p=0.24). CONCLUSIONS: Thorough assessment of vitamin D deficiency/insufficiency is required among patients with menstrual disorders, especially those overweighed and obese. Early screening and VD supplementation in women with estrogen-dependent disorders may become a part of routine management in order to optimize endocrine health....

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Journal Article 2018; 39(4): 321-324 PubMed PMID: 30531707 Citation  Keywords:  Adult, Female, Gestational Age, Humans, Laser Coagulation, Myopia:epidemiology, Ophthalmoscopy, Pregnancy, Pregnancy Complications:diagnosis, Puerperal Disorders:diagnosis, Retinal Degeneration:diagnosis, Retinal Diseases:diagnosis, Risk Factors, Young Ad.   

OBJECTIVES: Myopia is associated with increased frequency of retinal degenerative changes which are the risk factors of intra- and postpartal ophthalmological complications. Aim of this study was to analyze the degenerative lesions detected in opthalmological examination (including peripheral retinal lesions) as a potential risk factors for eyes' status in terms of delivery in myopic women. MATERIAL AND METHODS: 254 pregnant women affected with myopia underwent opthalmological examination as a screening method to examine retina. In case of any degenerative lesions, the qualification for laser photocoagulation treatment was performed. Furthermore, study group was divided into two subgroups due to presence or absence of the retinal lesions and opthalmological outcomes compared. Follow up examination was performed in every patient from the study group between 3 and 6 months after the delivery. RESULTS: Among 508 eyes, retinal lesions were revealed in 69 women (121 eyes) what constituted for 23.8%. In remaining 185 patients results of the opthalmological examination were normal. Average maternal age was higher in group affected with degenerative lesions (p<0.001). Myopia in women with retinal lesions ranged between -0.25 and -12 dioptries (D), while in 43 cases of degenerative lesions qualified for laser photocoagulation this value ranged between -0.5 and -12.0 D (p=ns). Postpartal follow-up examination did not reveal any abnormalities in this group, as well. CONCLUSION: Degenerative retinal lesions are present in one fourth of pregnant women. Both the severity and type of the lesions are not associated with severity of myopia. Among pregnant patients, retinal lesions occur in patients with more advanced maternal age. opthalmological examination remains an important prophylactic modality in retinal disorders, especially in primary retinal detachment due degenerative disorders....

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Journal Article 2019; 39(7): 481-488 PubMed PMID: 30860679 Citation  Keywords:  Accidental Falls:statistics & numerical data, Adult, Aged, Aged, 80 and over, Case-Control Studies, Czech Republic:epidemiology, Female, Hospitals:statistics & numerical data, Humans, Male, Middle Aged, Prevalence, Risk Factors, Young Adult,.   

THEORY: Patients falls have a multifactorial character and typically have multiple causalities. GOAL: The goal of the study was to identify risk factors for falls of hospitalized patients. METHODOLOGY: This was a case-control study. The study included 222 patients who experienced a fall during their hospitalization (cases) and 1,076 patients who did not fall during their hospitalization (controls). The study involved four hospitals in the South Bohemian Region of the Czech Republic. The study took place during the 2017 calendar year. RESULTS: The average age of patients who experienced a fall was 77.9 years. The group of cases included 5-times more patients with a history of falls than the controls. Patients who fell were in higher risk of falls than patients in the control group at hospital admission. The group of cases also had a higher prevalence of confused and restless patients; however, the group did not include a statistically significantly higher number of incontinent patients, patients with eating and drinking disorders, or patients with intravenous therapy than the control group. CONCLUSION: Interventions aimed at prevention of falls should be included in care plans, especially for older patients, patients who have fallen in the past, patients who have movement restriction, patients with cognitive dysfunction, and patients with increased need of assistance with basic daily activities....

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