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101.
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Aim

To investigate urban-rural differences in the distribution of risk factors for breast cancer.

Methods

We analyzed the data from the first round of the “Mamma” population based-screening program conducted in Croatia between 2007 and 2009 and self-reported questionnaire results for 924 patients with histologically verified breast cancer. Reproductive and anthropometric characteristics, family history of breast cancer, history of breast disease, and prior breast screening history were compared between participants from the city of Zagreb (n = 270) and participants from 13 counties with more than 50% of rural inhabitants (n = 654).

Results

The screen-detected breast cancer rate was 4.5 per 1000 mammographies in rural counties and 4.6 in the city of Zagreb, while the participation rate was 61% in rural counties and 59% in Zagreb. Women from Zagreb had significantly more characteristics associated with an increased risk of breast cancer (P < 0.001 in all cases): no pregnancies (15% vs 7%), late age of first pregnancy (≥30 years) (10% vs 4%), and the most recent mammogram conducted 2-3 years ago (32% vs 14%). Women from rural counties were more often obese (41% vs 28%) and had early age of first live birth (<20 years) (20% vs 7%, P < 0.001 for both).

Conclusion

Identification of rural-urban differences in mammography use and their causes at the population level can be useful in designing and implementing interventions targeted at the reduction of inequalities and modifiable risk factors.Significant differences in breast cancer frequency have been identified in different socioeconomic groups, ethnic groups, and between urban and rural populations (1,2). Living in rural areas may be associated with lower access to health care and mammography screening (3), as well as with late-stage diagnosis (4). This often means that patients need to travel great distances to receive care (5). Blair et al found that people in rural and urban areas were diagnosed with breast cancer at similar stages of the disease, although those from rural communities lacked basic cancer information because they did not have access to cancer education programs offered in urban areas (6). Robbins et al explained the higher breast cancer incidence in the San Francisco Bay Area than in other regions by known risk factors: parity, age at first full-term pregnancy, breast-feeding, age at menarche, and age at menopause (7). In Croatia, Polašek et al found that in a period without a national cancer screening program access to health care was the strongest cancer screening utilization predictor in adult rural population (8).Risk factors for breast cancer are mostly those related to the reproductive life of women (9,10): menarche, nulliparity or late age at first birth, late menopause, as well as hormonal factors, be they endogenous or exogenous (eg, term use of oral contraceptives or menopausal hormonal replacement). Other risk factors related to hormonal status include obesity and a diet characterized by a high caloric intake, low intake of fruits and vegetables, and lack of physical activity (11). Radiation, in particular during breast development, was also found to be a risk factor (12), while the role of contaminants, such as xenoestrogens and certain pesticides, remains controversial. Four- to 5-fold risk of developing breast cancer was associated with epithelial proliferative lesions, particularly atypical ductal or lobular hyperplasia (11).In Croatia, breast cancer is the leading cancer among women, amounting to 27% of new female cancer cases; moreover, the incidence rate in 2007 was 17% higher than in the previous year (13). In 2007, cancer incidence by county and age-standardized rates per 100 000 women varied considerably: from 273.1 (Šibensko-kninska county) to 437.7 (the city of Zagreb), but the prevalence of breast cancer risk factors remains unknown. A government-funded mammography screening program was established in October 2006 and has since been implemented in 21 counties, including the city of Zagreb (14).Population-based screening for breast cancer is conducted through mammographic examination of all women of a specified age at prescribed time intervals. The implementation of population-based screening requires technical resources and trained personnel for double reading of mammograms, as well as a major media campaign (15).Within a more extensive study of breast cancer risk factors, this study investigated urban-rural differences in reproductive, anthropometric, and family history of breast cancer and personal history of breast disease among women aged 50-69 from 13 rural counties and the city of Zagreb who participated in the first round of population-based mammography screening in Croatia.  相似文献   
105.
For successful immunotherapy for cancer, it is important to understand the immunological status of tumor antigen-specific CD8+ T cells in the tumor microenvironment during tumor progression. In this study, we monitored the behavior of B16OVA-Luc cells in mice immunized with a model tumor antigen ovalbumin (OVA). Using bioluminescence imaging, we identified the time series of OVA-specific CD8+ T-cell responses during tumor progression: initial progression, immune control, and the escape phase. As a result of analyzing the status of tumor antigen-specific CD8+ cells in those 3 different phases, we found that the expression of NKG2D defines tumor-reacting effector CD8+ T cells. NKG2D may control the fate and TOX expression of tumor-reacting CD8+ T cells, considering that NKG2D blockade in OVA-vaccinated mice delayed the growth of the B16OVA-Luc2 tumor and increased the presence of tumor-infiltrating OVA-specific CD8+ T cells.  相似文献   
106.
The objective was to investigate the association of nutrients and lifestyle modifiers with bone mineral density (BMD) and weight and/or body mass index (BMI) in 120 healthy Croatian postmenopausal women. The hip and spine BMD was assessed by Lunar Prodigy (GE Medical Systems). Nutrient assessment from 3-day records was analyzed using the US Department of Agriculture Food Composition Tables and the Croatian National Institute of Public Health database. Subjects were asked to record the consumption of alcohol, coffee, tea and mineral waters, the amount of salt added to foods and smoking habits, as well as involvement in recreational activities, walking and heavy housework. Spot urine samples were analyzed for calcium, magnesium, sodium, potassium and zinc and were normalized by creatinine. Alcohol showed statistically significant positive association with femur and spine BMD and its consumption was higher in subjects without osteoporosis. Urinary sodium/creatinine was significantly positively associated with femoral neck and trochanter BMD, while urinary calcium/creatinine was significantly negatively associated with trochanter, total femur and spine BMD. Consumption of mineral waters was inversely associated with weight/BMI and so were dietary fiber and magnesium. In conclusion, moderate alcohol consumption and urinary sodium were positively associated while urinary calcium was negatively associated with either hip and/or spine BMD. Mineral waters, higher fiber and magnesium intake were beneficial for weight/BMI in this population of apparently healthy Croatian women.  相似文献   
107.
The antagonist-sensitive binding of [3H]mepyramine to beef aortic membranes was as expected for binding to histamine H1-receptors. [3H]mepyramine binds rapidly and in saturable fashion to the specific receptor sites, specific binding reaching equilibrium in 3 min at 37°CScatchard's analysis of the binding data gave a dissociation constant of 3.0 nM for the radioligand-receptor complex and maximal number of binding sites: 31 fmol/mg protein. In the competition studies histamine H1-antagonists are more potent inhibitors of radioligand binding than H2-antagonist. They inhibit [3H]mepyramine binding in the following order: mepyramine >triprolidine  相似文献   
108.
In this study, we present evidence that red blood cell (RBC) membrane p68 in the Belgrade (b/b) rat is similar if not identical to rat serum albumin (RSA). Structural homology between RSA and the RBC p68 has been determined by a variety of biochemical and immunological criteria. This albumin-like protein is a normal constituent of rat RBC and it is partially exported by exosomes during erythroid differentiation. The endogenous origin of rat RBC albumin-like protein was demonstrated by monitoring protein synthesis in reticulocytes and by identification of reticulocyte mRNA for albumin. Haemolytic anaemia, either hereditary (b/b rat) or drug-induced (phenylhydrazine-treated normal rat), results in increased accumulation of the albumin-like protein in rat RBCs as a result of its induced synthesis.  相似文献   
109.
BACKGROUND: During short-term storage of hematopoietic cells (HCs) at 4°C a substantial decline in number and in functional capacity of progenitors occurs after 3 days. We hypothesized that physiologic O2 and CO2 concentrations of hematopoietic tissue microenvironment (approx. 3% O2 and approx. 6% CO2) could improve cell viability and functionality during storage at 4°C.
STUDY DESIGN AND METHODS: Mobilized peripheral blood (PB) CD34+ cells from multiple myeloma or non-Hodgkin's lymphoma patients were stored in flasks containing air (approx. 20% O2 and approx. 0.05% CO2) or 3% O2/6% CO2 atmosphere, for 3, 5, and 7 days at 4°C. The total number of cells, the number of cells in G0 or G1 phase of cell cycle, and the apoptosis rate were determined. The functional capacity of stored cells was assessed by the capacity of progenitors to form colonies in methylcellulose (colony-forming cells [CFCs]) and of stem cells to repopulate the bone marrow (BM) of immunodeficient mice (SCID-repopulating cell [SRC] assay).
RESULTS: The total number of viable cells and cells in G1 phase as well as the number of total CFCs were significantly higher at 3% O2/6% CO2 than in air at all time points. Cells in G0 phase and SRC were equally preserved in both conditions.
CONCLUSION: Atmosphere with low O2 and high CO2 concentration (3% O2/6% CO2) in hypothermia (+4°C) during 7 days of storage prevents cell damage and preserves a high number of functional HSCs and progenitors mobilized in PB by granulocyte–colony-stimulating factor.  相似文献   
110.
Molecular mechanisms of insulin resistance and associated diseases   总被引:24,自引:0,他引:24  
Insulin resistance is a state in which higher than normal concentrations of insulin are required for normal response. The most common underlying cause is central obesity, although primary insulin resistance in normal-weight individuals is also possible. Excess abdominal adipose tissue has been shown to release increased amounts of free fatty acids which directly affect insulin signalling, diminish glucose uptake in muscle, drive exaggerated triglyceride synthesis and induce gluconeogenesis in the liver. Other factors presumed to play the role in insulin resistance are tumour necrosis factor alpha, adiponectin, leptin, IL-6 and some other adipokines. Hyperinsulinaemia which accompanies insulin resistance may be implicated in the development of many pathological states, such as hypertension and hyperandrogenaemia. Insulin resistance underlies metabolic syndrome and is further associated with polycystic ovary syndrome and lipodystrophies. When beta-cells fail to secrete the excess insulin needed, diabetes mellitus type 2 emerges, which is, besides coronary heart disease, the main complication of insulin resistance and associated diseases.  相似文献   
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