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1.
Renal tubular diseases may present with osteopenia, osteoporosis or osteomalacia, as a result of significant derangements in body electrolytes. In case of insufficient synthesis of calcitriol, as in renal failure, the more complex picture of renal osteodystrophy may develop. Hypothetically, also disturbed renal production of BMP-7 and Klotho could cause bone disease. However, the acknowledgment that osteocytes are capable of producing FGF23, a phosphaturic hormone at the same time modulating renal synthesis of calcitriol, indicates that it is also bone that can influence renal function. Importantly, a feed-back mechanism exists between FGF23 and calcitriol synthesis, while Klotho, produced by the kidney, determines activity and selectivity of FGF23. Identification of human diseases linked to disturbed production of FGF23 and Klotho underlines the importance of this new bone-kidney axis. Kidney and bone communicate reciprocally to regulate the sophisticated machinery responsible for divalent ions homeostasis and for osseous or extraosseous mineralisation processes.  相似文献   
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Summary The use of Fourier transform coherent optical techniques in the pattern recognition of microscopic algae, i.e., diatoms, is described. The results of the construction of complex-valued filters for diatoms and their usefulness in algal identification are presented. Some general applications to water pollution monitoring and control are discussed.  相似文献   
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Several types of colorectal cancers are associated with a prominent lymphoid component, which is considered a positive prognostic factor.We report a case of a dome-type carcinoma of the cecum in a 57 year old female.The sessile, non-polypoid lesion histologically consisted of a tubulovillous adenoma with low-grade dysplasia.The submucosal invasive component showed low-grade architectural features that included cystically dilated glands containing eosinohilic debris. Immunohistochemical studies displayed retention of the four mistmach repair proteins, consistent with a stable phenotype. After 3 years, the patient remains free of recurrence.A literature review highlighted striking similarities between dome-type carcinoma and the gut-associated lymphoid tissue carcinoma, the two sharing an intimate association with the gut associated lymphoid tissue.The two variants might therefore be grouped into a unified category.  相似文献   
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Background

Polycyclic aromatic hydrocarbons (PAH) are both man-made and naturally occurring environmental pollutants that may be related to cardiometabolic health risk.

Objective

To determine whether PAH is associated with obesity in the adult population and to examine whether urinary concentrations of PAH metabolites are associated with differences in how obesity relates to 3 or more risk factors for the metabolic syndrome (3RFMetS), type 2 diabetes (T2D), hypertension, and dyslipidemia.

Methods

A total of 4765 adult participants from the 2001–2008 National Health and Nutrition Examination Survey were examined. The association between 8 urinary hydroxylated PAH metabolites, obesity, and health were examined using weighted logistic regressions adjusting for age, sex, ethnicity, PIR, smoking status, and urinary creatinine.

Results

There was a positive dose-dependent association between obesity and 2-phenanthrene quintiles (P trend <0.0001). Contrarily, higher quintiles of 1-naphthalene were associated with lower risk of obesity (P trend = 0.0004). For a given BMI, those in the highest quintile of 2-naphthalene, 2-fluorene, 3-fluorene and 2-phenanthrene had a 66–80% greater likelihood of 3RFMetS (P≤0.05) compared to low levels. Higher quintiles of 1-naphthalene, 2-naphthalene, 2-phenanthrene and 1-pyrene were associated with a 78–124% greater likelihood of T2D (P≤0.05) compared to low levels while high 1-naphthalene, 2-naphthalene, 2-fluorene, 3-fluorene and 2-phenanthrene were associated with a 38–68% greater likelihood of dyslipidemia (P≤0.05) compared to lower levels. Finally, 2-naphthalene and 2-phenanthrene were positively associated with hypertension (P trend = 0.008 and P trend = 0.02 respectively).

Conclusions

PAH is related to obesity and the expression of a number of obesity-related cardiometabolic health risk factors. Future research is needed to bring to light the mechanistic pathways related to these findings.  相似文献   
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CXCL8 was the first chemokine shown to be secreted by thyrocytes. Experimental data suggest that CXCL8 plays a role in thyroid homeostasis but its role in thyroid diseases remains poorly investigated. Clinical studies measuring the serum levels of CXCL8 in patients with autoimmune-thyroid-diseases reported conflicting results. Solid evidences support a role of CXCL8 as a tumor-promoting agent in several human cancers. Studies in thyroid cancer are still in their initial stage, but promising. Several evidences indicate that thyroid cancer may share with other human malignancies some of the effects of CXCL8 and highlight the possibility of using CXCL8 as a marker of aggressiveness. Basic and clinical evidences in favor or against a role for CXCL8 in thyroid diseases are discussed.  相似文献   
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The molecular mechanism by which the lipido‐sterolic extract of Serenoa repens (LSESr, Permixon®) affects prostate cells remains to be fully elucidated. In androgen‐independent PC3 prostate cancer cells, the LSESr‐induced effects on proliferation and apoptosis were evaluated by counting cells and using a FACScan cytofluorimeter. PC3 cells were stained with JC‐1 dye to detect mitochondrial membrane potential. Cell membrane lipid composition was evaluated by thin layer chromatography and gas chromatographic analysis. Akt phosphorylation was analyzed by Western blotting and cellular ultrastructure through electron microscopy. LSESr (12.5 and 25 µg/ml) administration exerted a biphasic action by both inhibiting proliferation and stimulating apoptosis. After 1 h, it caused a marked reduction in the mitochondrial potential, decreased cholesterol content and modified phospholipid composition. A decrease in phosphatidylinositol‐4,5‐bisphosphate (PIP2) level was coupled with reduced Akt phosphorylation. After 24 h, all of these effects were restored to pre‐treatment conditions; however, the saturated (SFA)/unsaturated fatty acid (UFA) ratio increased, mainly due to a significant decrease in ω6 content. The reduction in cholesterol content could be responsible for both membrane raft disruption and redistribution of signaling complexes, allowing for a decrease of PIP2 levels, reduction of Akt phosphorylation and apoptosis induction. The decrease in ω6 content appears to be responsible for the prolonged and more consistent increase in the apoptosis rate and inhibition of proliferation observed after 2–3 days of LSESr treatment. In conclusion, LSESr administration results in complex changes in cell membrane organization and fluidity of prostate cancer cells that have progressed to hormone‐independent status. J. Cell. Physiol. 219: 69–76, 2009. © 2008 Wiley‐Liss, Inc.  相似文献   
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NAD plays essential redox and non-redox roles in cell biology. In mammals, its de novo and recycling biosynthetic pathways encompass two independent branches, the “amidated” and “deamidated” routes. Here we focused on the indispensable enzymes gating these two routes, i.e. nicotinamide mononucleotide adenylyltransferase (NMNAT), which in mammals comprises three distinct isozymes, and NAD synthetase (NADS). First, we measured the in vitro activity of the enzymes, and the levels of all their substrates and products in a number of tissues from the C57BL/6 mouse. Second, from these data, we derived in vivo estimates of enzymes''rates and quantitative contributions to NAD homeostasis. The NMNAT activity, mainly represented by nuclear NMNAT1, appears to be high and nonrate-limiting in all examined tissues, except in blood. The NADS activity, however, appears rate-limiting in lung and skeletal muscle, where its undetectable levels parallel a relative accumulation of the enzyme''s substrate NaAD (nicotinic acid adenine dinucleotide). In all tissues, the amidated NAD route was predominant, displaying highest rates in liver and kidney, and lowest in blood. In contrast, the minor deamidated route showed higher relative proportions in blood and small intestine, and higher absolute values in liver and small intestine. Such results provide the first comprehensive picture of the balance of the two alternative NAD biosynthetic routes in different mammalian tissues under physiological conditions. This fills a gap in the current knowledge of NAD biosynthesis, and provides a crucial information for the study of NAD metabolism and its role in disease.  相似文献   
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