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71.
Patterning of the vertebrate skeleton requires the coordinated activity of Hox genes. In particular, Hox10 proteins are essential to set the transition from thoracic to lumbar vertebrae because of their rib-repressing activity. In snakes, however, the thoracic region extends well into Hox10-expressing areas of the embryo, suggesting that these proteins are unable to block rib formation. Here, we show that this is not a result of the loss of rib-repressing properties by the snake proteins, but rather to a single base pair change in a Hox/Paired box (Pax)-responsive enhancer, which prevents the binding of Hox proteins. This polymorphism is also found in Paenungulata, such as elephants and manatees, which have extended rib cages. In vivo, this modified enhancer failed to respond to Hox10 activity, supporting its role in the extension of rib cages. In contrast, the enhancer could still interact with Hoxb6 and Pax3 to promote rib formation. These results suggest that a polymorphism in the Hox/Pax-responsive enhancer may have played a role in the evolution of the vertebrate spine by differently modulating its response to rib-suppressing and rib-promoting Hox proteins.  相似文献   
72.
Introduction: Goal setting, led by the patient, is promising as an effective treatment for the management of chronic low back pain (CLBP); however, little is known about current practice. The aims of the study were to explore (1) current goal setting practice in CLBP among physiotherapists; (2) perceived barriers to goal setting in CLBP; and (3) relationship between clinician’s attitudes and beliefs and goal setting practice. Method: A cross-sectional observational survey. Results: The majority of respondents used goal setting with the main aim of facilitating self-management. The greatest number of goals were set with 50% therapist/50% patient involvement. The most common perceived barriers to goal setting related to time constraints and lack of skill and confidence. A higher biomedical score for treatment orientation of the therapist was associated with a lower patient involvement score. Conclusion: Goal setting is common practice for CLBP and is perceived as a high priority. It is more often a collaboration between therapist and patient rather than patient-led with treatment orientation of the physiotherapist a predictor of patient involvement. Education of healthcare professionals needs to include better understanding of chronic pain to orient them away from a biomedical treatment approach, as well as to enhance skills in facilitating patient involvement in goal setting.  相似文献   
73.
Objectives Hypovitaminosis D (HD) and secondary hyperparathyroidism (SHP) are common in elders, and many factors could contribute to them. The objectives of this study were to estimate the prevalence of HD, SHP, and its associated factors, in individuals living in nonprofit homes for elders in south Brazil. Design Cross-sectional study. Methods Serum 25-hydroxyvitamin D 25(OH)D, intact parathyroid hormone (PTH), total calcium, phosphorus, alkaline phosphatase, magnesium, creatinine, and albumin levels were measured in late spring, November, 2005. The presence of factors potentially related with HD and SHP—age, sex, weight, height, skin phototype, sun exposure, exercise, smoking, use of ≤5 medications or diuretics or alcohol, and daily calcium ingestion. Results 102 subjects age 77.8 ± 9.0 were included in the study. HD was found in 85.7% and SHP in 53% of the subjects. The estimated daily calcium ingestion was 720 mg. There was no association between serum 25(OH)D levels and any of the risk factors evaluated. Serum 25(OH)D levels were correlated with serum PTH (r = −0.358, P = 0.000), calcium (r = 0.306, P = 0.002), and albumin (r = 0.253, P = 0.011) levels. In univariate analysis, SHP was positively associated with age (P = 0.006), and female sex (0.007); and negatively associated with sunlight exposure (P = 0.020), GFR (P = 0.000), Ln25(OH)D (P = 0.002), and total serum calcium (P = 0.024). After multivariate model adjustment, age [OR 1.09 (CI 1.01–1.18); P = 0.024], Ln25(OH)D [OR 0.92 (CI 0.08–0.74); P = 0.013], GFR [OR 0.96 (CI 0.92–0.99); P = 0.013], and hydrochlorothiazide treatment [OR 7.63 (CI 1.67–34.9); P = 0.008] were independently associated with SHP. Conclusions HD and SHP are highly prevalent in elders living in old-age homes. No associations were established between common risk factors and low serum levels of 25(OH)D levels; however, SHP was independently related with age, 25(OH)D, GFR, and hydrochlorothiazide use.  相似文献   
74.
75.

Background

Lipoprotein(a) [Lp(a)], a major carrier of oxidized phospholipids (OxPL), is associated with an increased incidence of aortic stenosis (AS). However, it remains unclear whether elevated Lp(a) and OxPL drive disease progression and are therefore targets for therapeutic intervention.

Objectives

This study investigated whether Lp(a) and OxPL on apolipoprotein B-100 (OxPL-apoB) levels are associated with disease activity, disease progression, and clinical events in AS patients, along with the mechanisms underlying any associations.

Methods

This study combined 2 prospective cohorts and measured Lp(a) and OxPL-apoB levels in patients with AS (Vmax >2.0 m/s), who underwent baseline 18F-sodium fluoride (18F-NaF) positron emission tomography (PET), repeat computed tomography calcium scoring, and repeat echocardiography. In vitro studies investigated the effects of Lp(a) and OxPL on valvular interstitial cells.

Results

Overall, 145 patients were studied (68% men; age 70.3 ± 9.9 years). On baseline positron emission tomography, patients in the top Lp(a) tertile had increased valve calcification activity compared with those in lower tertiles (n = 79; 18F-NaF tissue-to-background ratio of the most diseased segment: 2.16 vs. 1.97; p = 0.043). During follow-up, patients in the top Lp(a) tertile had increased progression of valvular computed tomography calcium score (n = 51; 309 AU/year [interquartile range: 142 to 483 AU/year] vs. 93 AU/year [interquartile range: 56 to 296 AU/year; p = 0.015), faster hemodynamic progression on echocardiography (n = 129; 0.23 ± 0.20 m/s/year vs. 0.14 ± 0.20 m/s/year] p = 0.019), and increased risk for aortic valve replacement and death (n = 145; hazard ratio: 1.87; 95% CI: 1.13 to 3.08; p = 0.014), compared with lower tertiles. Similar results were noted with OxPL-apoB. In vitro, Lp(a) induced osteogenic differentiation of valvular interstitial cells, mediated by OxPL and inhibited with the E06 monoclonal antibody against OxPL.

Conclusions

In patients with AS, Lp(a) and OxPL drive valve calcification and disease progression. These findings suggest lowering Lp(a) or inactivating OxPL may slow AS progression and provide a rationale for clinical trials to test this hypothesis.  相似文献   
76.
Objective: To determine the utility of ultrasound (US) in late pregnancy for identifying fetuses with growth disturbances.

Methods: This study was designed as a retrospective study of birth weights over a 12-month period at the Royal Hobart Hospital (RHH) and Barwon Health (BH). Data were collected from the discharge summaries and medical records at both hospitals targeting abnormal fetal weight below 10th percentile (small for gestational age – SGA) and above 90th percentile (large for gestational age – LGA).

Results: There were 4079 study patients from both hospitals. After weight adjustment by gender and gestational age, an abnormal fetal weight was detected in 741 cases (babies over the 90th percentile or below 10th percentile). One hundred and twenty-eight patients with high-risk pregnancies were excluded. Therefore, a total of 613 patients remained that were considered to be low-risk pregnancies with abnormal foetal growth; 305 patients from RHH and 308 from BH. The antenatal detection rate for LGA was 35.9%, at RHH by combination of US and clinical evaluation, while for BH it was 34.8% by clinical evaluation alone (p?=?0.910). The antenatal detection rate for SGA was 36.8% via US and clinical evaluation at RHH and 54.5% by clinical evaluation alone at BH (p?=?0.006).

Conclusion: This study shows no benefit in the use of routine US for the antenatal diagnosis of LGA compared with clinical evaluation in low-risk pregnancies. US evaluation was inferior to clinical evaluation in the antenatal diagnosis of SGA in low-risk pregnancies.  相似文献   

77.
78.
Background: Epidemiological investigations on Toxoplasma gondii infection have found a significant association between human toxoplasmosis and consumption of raw or undercooked meat. The present study aimed to characterize genotypes of T. gondii in 20 cattle, 40 sheep, 15 goats and 16 pigs from the North of Portugal.Methods: Nested PCR amplified the surface antigen 2 (SAG2) gene. Sequencing analysis was performed in order to assess the prevalence of SAG2 type strains (I, II and III). Results: Three and 4 strains of SAG2 type II were identified in heart samples of cattle and sheep, respectively. Three SAG2 type II strains were detected in brain, diaphragm and heart of 3 pigs. Three strains detected in heart samples of 3 goats belonged to SAG2 types I or II; with the same result being observed in heart samples from 2 sheep and in 2 brain and 1 heart samples from 3 pigs. Conclusion: SAG2 type II has been shown for the first time to infect cattle in North of Portugal. In addition, SAG2 type II has also been confirmed as the predominant strain in sheep and pigs in the same region. This is the first molecular report of T. gondii in goats from Portugal.Key Words: Genotypes, Portugal, Ruminants, Swine, Toxoplasma gondii  相似文献   
79.
Nutritional factors such as casein hydrolysates and long chain polyunsaturated fatty acids have been proposed to exert beneficial metabolic effects. We aimed to investigate how a casein hydrolysate (eCH) and long chain polyunsaturated fatty acids could affect human primary adipocyte function in vitro. Incubation conditions with the different nutritional factors were validated by assessing cell vitality with lactate dehydrogenase (LDH) release and neutral red incorporation. Intracellular triglyceride content was assessed with Oil Red O staining. The effect of eCH, a non-peptidic amino acid mixture (AA), and long-chain polyunsaturated fatty acids (LC-PUFAs) on adiponectin and leptin secretion was determined by enzyme-linked immunosorbent assay (ELISA). Intracellular adiponectin expression and nuclear factor-κB (NF-κB) activation were analyzed by Western blot, while monocyte chemoattractant protein-1 (MCP-1) release was explored by ELISA. The eCH concentration dependently increased adiponectin secretion in human primary adipocytes through its intrinsic peptide bioactivity, since the non-peptidic mixture, AA, could not mimic eCH’s effects on adiponectin secretion. Eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and DHA combined with arachidonic acid (ARA) upregulated adiponectin secretion. However, only DHA and DHA/ARA exerted a potentanti-inflammatory effect reflected by prevention of tumor necrosis factor-α (TNF-α) induced NF-κB activation and MCP-1 secretion in human adipocytes. eCH and DHA alone or in combination with ARA, may hold the key for nutritional programming through their anti-inflammatory action to prevent diseases with low-grade chronic inflammation such as obesity or diabetes.  相似文献   
80.
The antimicrobial properties of silver nanoparticles (AgNPs) have made these particles one of the most used nanomaterials in consumer products. Therefore, an understanding of the interactions (unwanted toxicity) between nanoparticles and human cells is of significant interest. The aim of this study was to assess the in vitro cytotoxicity effects of silver nanoclusters (AgNC, < 2 nm diameter) on peripheral blood mononuclear cells (PBMC). Using flow cytometry and comet assay methods, we demonstrate that exposure of PBMC to AgNC induced intracellular reactive oxygen species (ROS) generation, DNA damage and apoptosis at 3, 6 and 12 h, with a dose‐dependent response (0.1, 1, 3, 5 and 30 µg ml–1). Advanced electron microscopy imaging of complete and ultrathin‐sections of PBMC confirmed the cytotoxic effects and cell damage caused by AgNC. The present study showed that AgNC produced without coating agents induced significant cytotoxic effects on PBMC owing to their high aspect ratio and active surface area, even at much lower concentrations (<1 µg ml–1) than those applied in previous studies, resembling what would occur under real exposure conditions to nanosilver‐functionalized consumer products. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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