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101.
Ecotoxicology - Nanomaterials have revolutionized many scientific fields and are widely applied to address environmental problems and to develop novel health care strategies. However, their...  相似文献   
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Allen K  Shykoff BE  Izzo JL 《Hypertension》2001,38(4):815-820
In the present study, we evaluated the effect of a nonevaluative social support intervention (pet ownership) on blood pressure response to mental stress before and during ACE inhibitor therapy. Forty-eight hypertensive individuals participated in an experiment at home and in the physician's office. Participants were randomized to an experimental group with assignment of pet ownership in addition to lisinopril (20 mg/d) or to a control group with only lisinopril (20 mg/d). On each study day, blood pressure, heart rate, and plasma renin activity were recorded at baseline and after each mental stressor (serial subtraction and speech). Before drug therapy, mean responses to mental stress did not differ significantly between experimental and control groups in heart rate (94 [SD 6.8] versus 93 [6.8] bpm), systolic blood pressure (182 [8.0] versus 181 [8.3] mm Hg), diastolic blood pressure (120 [6.6] versus 119 [7.9] mm Hg), or plasma renin activity (9.4 [0.59] versus 9.3 [0.57] ng. mL(-1). h(-1)). Lisinopril therapy lowered resting blood pressure by approximately 35/20 mm Hg in both groups, but responses to mental stress were significantly lower among pet owners relative to those who only received lisinopril (P<0.0001; heart rate 81 [6.3] versus 91 [6.5] bpm, systolic blood pressure 131 [6.8] versus 141 [7.8] mm Hg, diastolic blood pressure 92 [6.3] versus 100 [6.8] mm Hg, and plasma renin activity 13.9 [0.92] versus 16.1 [0.58] ng. mL(-1). h(-1)). We conclude that ACE inhibitor therapy alone lowers resting blood pressure, whereas increased social support through pet ownership lowers blood pressure response to mental stress.  相似文献   
104.
The cilium is a signaling platform of the vertebrate cell. It has a critical role in polycystic kidney disease and nephronophthisis. Cilia have been detected on endothelial cells, but the function of these organelles in the vasculature remains incompletely defined. In this study, using genetic and chemical genetic tools in the model organism zebrafish, we reveal an essential role of cilia in developmental vascular integrity. Embryos expressing mutant intraflagellar transport genes, which are essential and specific for cilia biogenesis, displayed increased risk of developmental intracranial hemorrhage, whereas the morphology of the vasculature remained normal. Moreover, cilia were present on endothelial cells in the developing zebrafish vasculature. We further show that the involvement of cilia in vascular integrity is endothelial autonomous, because endothelial-specific re-expression of intraflagellar transport genes in respective mutants rescued the intracranial hemorrhage phenotype. Finally, whereas inhibition of Hedgehog signaling increased the risk of intracranial hemorrhage in ciliary mutants, activation of the pathway rescued this phenotype. In contrast, embryos expressing an inactivating mutation in pkd2, one of two autosomal dominant cystic kidney disease genes, did not show increased risk of developmental intracranial hemorrhage. These results suggest that Hedgehog signaling is a major mechanism for this novel role of endothelial cilia in establishing vascular integrity.  相似文献   
105.
CKD is increasingly prevalent in pregnancy. In the Torino-Cagliari Observational Study (TOCOS), we assessed whether the risk for adverse pregnancy outcomes is associated with CKD by comparing pregnancy outcomes of 504 pregnancies in women with CKD to outcomes of 836 low-risk pregnancies in women without CKD. The presence of hypertension, proteinuria (>1 g/d), systemic disease, and CKD stage (at referral) were assessed at baseline. The following outcomes were studied: cesarean section, preterm delivery, and early preterm delivery; small for gestational age (SGA); need for neonatal intensive care unit (NICU); new onset of hypertension; new onset/doubling of proteinuria; CKD stage shift; “general” combined outcome (preterm delivery, NICU, SGA); and “severe” combined outcome (early preterm delivery, NICU, SGA). The risk for adverse outcomes increased across stages (for stage 1 versus stages 4–5: “general” combined outcome, 34.1% versus 90.0%; “severe” combined outcome, 21.4% versus 80.0%; P<0.001). In women with stage 1 CKD, preterm delivery was associated with baseline hypertension (odds ratio [OR], 3.42; 95% confidence interval [95% CI], 1.87 to 6.21), systemic disease (OR, 3.13; 95% CI, 1.51 to 6.50), and proteinuria (OR, 3.69; 95% CI, 1.63 to 8.36). However, stage 1 CKD remained associated with adverse pregnancy outcomes (general combined outcome) in women without baseline hypertension, proteinuria, or systemic disease (OR, 1.88; 95% CI, 1.27 to 2.79). The risk of intrauterine death did not differ between patients and controls. Findings from this prospective study suggest a “baseline risk” for adverse pregnancy-related outcomes linked to CKD.  相似文献   
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PURPOSE: To estimate the prevalence of neurological signs and their association with limitations in mobility and falls in a sample of older persons without known neurological disease. METHODS: A neurologist examined 818 participants from the InCHIANTI study who were aged > or =65 years and who did not have cognitive impairment, treatment with neuroleptics, and a history of neurological disease. Mobility was assessed as walking speed and self-reported ability to walk at least 1 km without difficulty. Participants were asked to report falls that had occurred in the previous 12 months. RESULTS: Less than 20% (160/818) of participants had no neurological signs. Neurological signs were more prevalent in older participants and those with impaired mobility. When all neurological signs were included in sex-and age-adjusted multivariate models, 10 were mutually independent correlates of poor mobility. After adjusting for age and sex, the number of neurological signs was associated with progressively slower walking speed (P <0.001), a higher probability of reported inability to walk 1 km (P <0.001), and a history of falls (P <0.05). CONCLUSION: Neurological signs are independent correlates of limitations in mobility and falls in older persons who have no clear history of neurological disease.  相似文献   
108.
Retinol-binding protein 4 (RBP4) is an adipocytokine associated with insulin resistance (IR). We tested serum levels of RBP4 to assess its link with steatosis in patients with genotype 1 chronic hepatitis C (CHC) or nonalcoholic fatty liver disease (NAFLD). Nondiabetic patients with CHC (n = 143) or NAFLD (n = 37) were evaluated by liver biopsy and anthropometric and metabolic measurements, including IR by the homeostasis model assessment. Biopsies were scored by Scheuer classification for CHC, and Kleiner for NAFLD. Steatosis was tested as a continuous variable and graded as absent-mild <30%, or moderate-severe > or =30%. Thirty nondiabetic, nonobese blood donors served as controls. RBP4 levels were measured by a human competitive enzyme-linked immunosorbent assay kit (AdipoGen). Mean values of RBP4 were similar in NAFLD and CHC (35.3 +/- 9.3 microg/L versus 36.8 +/- 17.6; P = 0.47, respectively), and both were significantly higher than in controls (28.9 +/- 12.1; P = 0.02 and P = 0.01, respectively). RBP4 was higher in CHC patients with steatosis than in NAFLD (42.1 +/- 19.7 versus 35.2 +/- 9.3; P = 0.04). By linear regression, RBP4 was independently linked to steatosis only (P = 0.008) in CHC, and to elevated body mass index (P = 0.01) and low grading (P = 0.04) in NAFLD. By linear regression, steatosis was independently linked to homeostasis model assessment score (P = 0.03) and high RBP4 (P = 0.003) in CHC. By logistic regression, RBP4 was the only variable independently associated with moderate-severe steatosis in CHC (odds ratio, 1.045; 95% confidence interval, 1.020 to 1.070; P = 0.0004), whereas waist circumference was associated with moderate-severe steatosis in NAFLD (odds ratio, 1.095; 95% confidence interval, 1.007 to 1.192; P = 0.03). CONCLUSION: In nondiabetic, nonobese patients with genotype 1 CHC, serum RBP4 levels might be the expression of a virus-linked pathway to steatosis, largely unrelated to IR.  相似文献   
109.
BACKGROUND: Inadequate blood pressure (BP) control could be due to incorrect management of hypertensives caused by the lack of interaction between general practitioners (GP) and hypertension specialists. OBJECTIVES: To test the effectiveness on BP and total cardiovascular risk (TCVR) control of an internet-based digital network connecting specialists and GPs. METHODS: We created a network among the Hypertension Clinic, Federico II University (Naples, Italy), 23 hospital-based hypertension clinics and 60 GPs from the area (CampaniaSalute Network, CS). Randomized GPs enrolled in CS could update online records of patients (n = 1979). As a control, we included 2045 patients referred to the specialist clinics by GPs from outside the network. All patients completed a 2-year follow-up. RESULTS: CS provided a larger reduction in BP [systolic/diastolic BP (SBP/DBP): 7.3 +/- 0.4/5.4 +/- 0.3 versus 4.1 +/- 0.4/3.1 +/- 0.26 mmHg, CS versus control; P < 0.001 for both] and percentage of patients with BP < 140/90 mmHg (CS versus control: baseline, 33 versus 34%, NS; end of follow-up, 51 versus 47%, chi = 13.371; P < 0.001). A European Society of Hypertension-European Society of Cardiology (ESH/ESC) TCVR score was calculated [from 1 (average) to 5 (very high TCVR)]. The CS group showed a reduction in the mean TCVR score (CS: from 3.5 +/- 0.02 to 3.2 +/- 0, P < 0.01, ANOVA; control group: 3.5 +/- 0.03 to 3.4 +/- 0.03, NS) and, accordingly, fatal and non-fatal major cardiovascular events (MACE) were less frequent (2.9 versus 4.3%; chi = 5.047, P < 0.02). CS predicts fewer MACE in multiple binary regression analysis (beta:-7.27, P < 0.008) reducing the risk for MACE compared to control [odds ratio (OR): 0.838; 95% confidence interval (CI): 0.73-0.96]. CONCLUSION: Our results support the idea that telemedicine can achieve better control of BP and TCVR.  相似文献   
110.
To evaluate the relationship between inflammatory markers and severity of asthma in children, the amount of interleukin-8 (IL-8) and granulocyte/macrophage colony-stimulating factor (GM-CSF) released by peripheral blood mononuclear cells, exhaled nitric oxide (FE NO) levels, p65 nuclear factor-kappaB subunit, and phosphorylated IkBalpha expression by peripheral blood mononuclear cells were assessed in six control subjects, 12 steroid-naives subjects with intermittent asthma, and 17 children with moderate asthma. To investigate their predictive value, biomarker levels were correlated with the number of exacerbations during a 18-month follow-up period. We found that GM-CSF release was higher in moderate and intermittent asthmatics than in control subjects, whereas IL-8 release was higher in moderate than in intermittent asthmatics and control subjects. FE NO levels were similar among study groups. In moderate asthmatics, IL-8, GM-CSF, and FE NO significantly correlated with the exacerbation numbers. Moreover, p65 and phosphorylated IkBalpha levels were greater in moderate than in intermittent asthmatics and control subjects. According to GM-CSF, IL-8, and FE NO levels, two distinct subgroups of moderate asthmatics (low and high producers) were identified. High producers experienced more exacerbations than low producers. This study shows ongoing inflammation associated with biological and clinical heterogeneity in moderate asthmatics despite regular treatment and proposes that large prospective studies confirm the importance of biomarkers to assess inflammation and asthma control in children with asthma.  相似文献   
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