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11.
BACKGROUND: On 21 May 2005, the Norwegian health authorities were alerted by officials from a local hospital that several recent patients had received the diagnosis of legionnaires disease; all patients resided in 2 neighboring municipalities. We investigated the outbreak to identify the source and to implement control measures. METHODS: We interviewed all surviving case patients and investigated and harvested samples from 23 businesses with cooling towers and other potential infection sources. The locations of the businesses and the patients' residences and movements were mapped. We calculated attack rates and risk ratios among people living within various radii of each potential source. Isolates of Legionella pneumophila were compared using molecular methods. RESULTS: Among 56 case patients, 10 died. The case patients became ill 12-25 May, resided up to 20 km apart, and had not visited places in common. Those living up to 1 km from a particular air scrubber had the highest risk ratio, and only for this source did the risk ratio decrease as the radius widened. Genetically identical L. pneumophila serogroup 1 isolates were recovered from patients and the air scrubber. The air scrubber is an industrial pollution-control device that cleans air for dust particles by spraying with water. The circulating water had a high organic content, pH of 8-9, and temperature of 40 degrees C. The air was expelled at 20 m/s and contained a high amount of aerosolized water. CONCLUSIONS: The high velocity, large drift, and high humidity in the air scrubber may have contributed to the wide spread of Legionella species, probably for >10 km. The risk of Legionella spread from air scrubbers should be assessed.  相似文献   
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Education has been related to various advantageous lifetime outcomes. Here, using longitudinal structural MRI data (4,422 observations), we tested the influential hypothesis that higher education translates into slower rates of brain aging. Cross-sectionally, education was modestly associated with regional cortical volume. However, despite marked mean atrophy in the cortex and hippocampus, education did not influence rates of change. The results were replicated across two independent samples. Our findings challenge the view that higher education slows brain aging.  相似文献   
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Purpose Experimental in vitro models including well-characterised cell lines can be used to identify possible new therapeutic targets for the treatment of osteosarcoma. Culture media including inactivated serum is often recommended for in vitro culture of osteosarcoma cells, but the serum component then represents a nonstandardised parameter including a wide range of unidentified mediators. To improve the standardisation we have investigated whether serum-free culture media can be used in experimental in vitro studies of osteosarcoma cell lines.Methods The seven osteosarcoma cell lines Cal72, SJSA-1, Saos-2, SK-ES-1, U2OS, 143.98.2, and KHOS-32IH were cultured in vitro in various serum-free media and media supplemented with 10% heat-inactivated fetal calf serum (FCS).Results Although proliferation often was relatively low in serum-free media (X-vivo 10, X-vivo 15, X-vivo 20, Stem Span SFEM), some cell lines (Cal72, KHOS-32IH, Saos-2) showed proliferation comparable with the recommended FCS-containing media even when using serum-free conditions. The optimal serum-free medium then varied between cell lines. We also compared 6 different FCS-containing media (including Stem Span with 10% FCS) and the optimal FCS-containing medium varied between cell lines. However, all cell lines proliferated well in Stem Span with FCS, and this medium was regarded as optimal for four of the lines. FCS could not be replaced by fatty acids or low density lipoprotein when testing the Stem Span medium. The release of a wide range of soluble mediators showed only minor differences when using serum-free and FCS-containing media (including Stem Span with and without FCS), and serum-free Stem Span could also be used for in vitro studies of mitogen-stimulated T cell activation in the presence of accessory osteosarcoma cells. The use of Stem Span with 10% FCS allowed the release of a wide range of chemokines by osteosarcoma cell lines (Cal72, SJSA-1), and the chemokine release profile was very similar to the fibroblast lines Hs27 and HFL1.Conclusions Serum-free culture media can be used for in vitro studies of several osteosarcoma cell lines, but the optimal medium varies between cell lines and thus depends on: (i) the cell lines to be investigated/compared; (ii) the functional characteristic that is evaluated (proliferation, cytokine release); and (iii) whether coculture experiments are included.  相似文献   
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Purpose

The purpose of this study is to assess the exocrine and neuroendocrine properties of tumour cells in diffuse gastric cancer with signet ring cell differentiation.

Material and methods

Mucin mRNA and protein expressions (MUC1, 2, 3, 4, 5AC, 6 and MUC13) were assessed by immunohistochemistry and in situ hybridization. The neuroendocrine properties were evaluated by protein and mRNA expression of the general neuroendocrine markers chromogranin A and synaptophysin.

Results

No MUC expression was observed in signet ring tumour cells including the amorphous substance in any of the nine cases. All cases showed immunoreactivity to synaptophysin, and seven out of nine cases immunoreactivity to chromogranin A in signet ring and non-signet ring tumour cells. Chromogranin A mRNA expression was observed in tumour cells in all samples with retained mRNA.

Conclusions

The lack of MUC protein and mRNA in signet ring tumour cells suggests the amorphous substance is not mucin. The lack of MUC mRNA expression in non-signet ring tumour cells questions exocrine differentiation in this tumour group. The abundant protein expression of the general neuroendocrine markers CgA and synaptophysin, and mRNA expression in tumour cells strengthens the hypothesis that this tumour group may be of neuroendocrine origin.  相似文献   
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Acute myeloid leukaemia (AML) is a heterogeneous malignancy. Intracellular signalling through the phosphatidylinositol 3‐kinase (PI3K)‐Akt‐mammalian target of rapamycin (mTOR) pathway is important for regulation of cellular growth and metabolism, and inhibitors of this pathway is considered for AML treatment. Primary human AML cells, derived from 96 consecutive adult patients, were examined. The effects of two mTOR inhibitors (rapamycin, temsirolimus) and two PI3K inhibitors (GDC‐0941, 3‐methyladenine) were studied, and we investigated cytokine‐dependent proliferation, regulation of apoptosis and global gene expression profiles. Only a subset of patients demonstrated strong antiproliferative effects of PI3K‐mTOR inhibitors. Unsupervised hierarchical clustering analysis identified two main clusters of patients; one subset showing weak or absent antiproliferative effects (59%) and another group showing a strong growth inhibition for all drugs and concentrations examined (41%). Global gene expression analyses showed that patients with AML cell resistance against PI3K‐mTOR inhibitors showed increased mRNA expression of the CDC25B gene that encodes the cell cycle regulator Cell Division Cycle 25B. The antileukaemic effect of PI3K‐Akt‐mTOR inhibition varies between patients, and resistance to these inhibitors is associated with the expression of the cell cycle regulator CDC25B, which is known to crosstalk with the PI3K‐Akt‐mTOR pathway and mediate rapamycin resistance in experimental models.  相似文献   
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Treatments offered at the Maharishi Ayurveda Health Centre in Norway are based on Maharishi Vedic Medicine (MVM). MVM is a consciousness-based revival by Maharishi Mahesh Yogi, the founder of the Transcendental Meditation (TM) program of the ancient Ayurvedic medicine tradition in India. To extend from 6 to 24 months, a pilot study of the effects of the treatment program at the Health Centre on fibromyalgia. Retesting 2 years after a clinical trial. In this intention to treat study, 31 women with a diagnosis of fibromyalgia received an individually tailored program of (1) physiological purification therapy (Maharishi Panchakarma) and (2) Ayurvedic recommendations regarding daily routine and diet including a novel approach to food intolerance. Five subjects chose to learn TM for stress reduction, pain management and personal development. All were recommended Ayurvedic herbal products for follow-up treatment. A modified Fibromyalgia Impact Questionnaire (FIQ) that included seven dimensions. Scores at 24 months follow-up were compared with pre-treatment scores. At 24-months follow-up, there were significant reductions (26% to 44%) in six of the seven fibromyalgia dimensions: impairment of working ability, pain, tiredness, morning tiredness, stiffness and anxiety. The 7th, depression, decreased 32% (borderline significant). At 24 months, the four subjects who continued practising TM, had almost no symptoms and significantly lower FIQ change scores (−92% to 97%) than the non-meditators on all outcomes. This pilot study suggests that the treatments and health promotion programs offered at the Maharishi Ayurveda Health Centre in Norway lead to long-term reductions in symptoms of fibromyalgia, which is considered a treatment-resistant condition, and further studies are warranted.  相似文献   
20.

Background

As most pancreatic neuroendocrine tumors (PNET) are relatively small and solitary, they may be considered well suited for removal by a minimally invasive approach. There are few large series that describe laparoscopic surgery for PNET. The primary aim of this study was to describe the feasibility, outcome, and histopathology associated with laparoscopic pancreatic surgery (LS) of PNET in a large series.

Methods

All patients with PNET who underwent LS at a single hospital from March 1997 to April 2011 were included retrospectively in the study.

Results

A total of 72 patients with PNET underwent 75 laparoscopic procedures, out of which 65 were laparoscopic resections or enucleations. The median operative time of all patients who underwent resections or enucleations was 175 (60–520) min, the median blood loss was 300 (5–2,700) ml, and the median length of hospital stay was 7 (2–27) days. The overall morbidity rate was 42 %, with a surgical morbidity rate of 21 % and postoperative pancreatic fistula (POPF) formation in 21 %. Laparoscopic enucleations were associated with a higher rate of POPF than were laparoscopic resections. Five-year disease-specific survival rate was 90 %. The T stage, R stage, and a Ki-67 cutoff value of 5 % significantly predicted 5-year survival.

Conclusion

LS of PNET is feasible with acceptable morbidity and a good overall disease-specific long-term prognosis.  相似文献   
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