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41.
Protein deficiency is associated with impaired titanium osseointegration. We studied whether systemic treatment with PTH or pamidronate could influence the resistance to pull-out of titanium rods implanted into rats proximal tibia under normal and isocaloric low protein intake. PTH or pamidronate prevented the deleterious effects of protein undernutrition on bone microarchitecture close to the implant and on mechanical fixation. PTH even significantly improved implant osseointegration. INTRODUCTION: Protein deficiency is highly prevalent among elderly patients hospitalized in orthopedic wards. Reduced protein intake impairs titanium osseointegration in rats. Whether stimulator of bone formation or inhibitor of bone resorption could improve implant osseointegration under protein deprivation is not known. We studied the effects of systemic treatment with PTH or pamidronate on the resistance to pull-out of titanium rods implanted into rats proximal tibia under normal and isocaloric low protein intake. MATERIALS AND METHODS: We measured the resistance to pull-out 1-mm-diameter titanium rods implanted into the proximal tibias of 49 adult female rats receiving a normal or an isocaloric low protein diet. After 2 wk on either diet, the implants were inserted, and the rats received PTH(1-34), pamidronate or saline vehicle for 8 wk. The tibias were removed for microCT morphometry, followed by the evaluation of pull-out strength. RESULTS: Pull-out strength was lower in rats fed an isocaloric low protein diet compared with rats fed a normal protein intake (-29%). PTH and pamidronate significantly increased pull-out strength in animals fed a normal or a low protein diet, the effect of PTH being of higher magnitude. The PTH- or pamidronate-mediated increase in pull-out strength was associated with significant increases of relative bone volume, bone-to-implant contact, and trabecular thickness, whereas trabecular spacing was reduced, in the vicinity of the implants. CONCLUSIONS: We confirmed that isocaloric low protein intake impairs titanium implant osseointegration. PTH or pamidronate prevented the deleterious effects of protein undernutrition and even significantly improved the implant osseointegration. These results indicate that systemic administration of PTH or pamidronate could be considered for preventing uncemented arthroplasty loosening in protein undernourished patients.  相似文献   
42.
OBJECTIVE: To assess the efficacy and safety of aripiprazole for psychosis associated with Alzheimer dementia (AD). METHODS: In this double-blind, multicenter study, 487 institutionalized patients with psychosis associated with AD were randomized to placebo or aripiprazole, 2, 5 or 10 mg/day. Primary efficacy assessment was the mean change from baseline to week 10 on the Neuropsychiatric Inventory-Nursing Home (NPI-NH) version Psychosis Subscale score. Secondary measures included NPI-NH Total, Clinical Global Impression-Severity of Illness (CGI-S), Brief Psychiatric Rating Scale (BPRS) Core and Total, and the Cohen-Mansfield Agitation Inventory (CMAI) scores. RESULTS: Aripiprazole 10 mg/day showed significantly greater improvements (mean change [2 x SD]) than placebo on the NPI-NH Psychosis Subscale (-6.87 [8.6] versus -5.13 [10.0]; F = 6.29, df = 1, 422, p = 0.013 by analysis of covariance [ANCOVA]); CGI-S (-0.72 [1.8] versus -0.46 [1.6]; F = 4.68, df = 1, 419, p = 0.031 [ANCOVA]); BPRS Total (-7.12 [18.4] versus -4.17 [21.6]; F = 4.72, df = 1, 399, p = 0.030 [ANCOVA]); BPRS Core (-3.07 [6.9] versus -1.74 [7.8]; F = 7.30, df = 1, 407, p = 0.007 [ANCOVA]); CMAI (-10.96 [22.6] versus -6.64 [28.6]; F = 5.23, df = 1, 410, p = 0.023 [ANCOVA]), and NPI-NH Psychosis response rate (65 versus 50%; chi(2) = 5.52, df = 1, p = 0.019 [CMH]). Aripiprazole 5 mg/day showed significant improvements versus placebo on BPRS and CMAI scores. Aripiprazole 2 mg/day was not efficacious. Cerebrovascular adverse events were reported: aripiprazole 2 mg/day, N = 1; 5 mg/day, N = 2; 10 mg/day, N = 4; placebo, N = 0. No deaths in any group (aripiprazole 2 mg/day, 3%; 5 mg/day, 2%; 10 mg/day, 7%; placebo, 3%) were considered to be treatment-related. CONCLUSION: Aripiprazole 10 mg/day was efficacious and safe for psychosis associated with AD, significantly improving psychotic symptoms, agitation, and clinical global impression. However, clinicians should be aware of the safety considerations of atypical antipsychotic uses in this population.  相似文献   
43.
44.
Porcine small intestinal submucosa (SIS) is a cell-free collagen matrix that has demonstrated its ability as scaffold material for constructive remodeling of damaged or missing tissue. The purpose of this study was to evaluate the morphology and function of esophagoplasty in rat using a porcine SIS scaffold for the repair of a semi-circumferential defect in the cervical or in the abdominal esophagus. Sixty-seven rats underwent surgical excision of the anterior wall either of the cervical or of the abdominal esophagus and subsequent repair of the defect with an SIS patch graft. Outcomes of weight gain, signs of dysphagia, hematological and serum chemistry parameters, and barium swallow studies were used to assess the progress of healing and function over a 150-day time period. The grafts were studied for gross changes and histology at predetermined time points. Ninety-four percent of the SIS-treated rats survived, showing no significant differences in survival rate between groups. The grafted animals did well, without signs of dysphagia, and gaining weight. Barium swallow studies showed no evidence of fistula, significant stenosis, or diverticula. No hematological or serum biochemistry abnormalities were found. By 150 days, the SIS graft was replaced with esophageal-derived tissues. Specimens were completely lined by keratinized stratified squamous epithelium and showed complete regeneration of muscle fibers and scarce immunoreactivity for nerve. In the rat model, a patch graft technique using porcine SIS appears to induce esophageal regrowth either in cervical and abdominal esophagus. The repair mechanism occurred through a regenerative healing process.  相似文献   
45.
OBJECTIVE: This study analyzes the differences in psychological variables and symptomatology between temporomandibular disorder diagnosis subgroups. STUDY DESIGN: The sample included 114 temporomandibular disorder patients that were evaluated in coping, distress, and temporomandibular characteristics. Diagnostic muscular (n = 58) and articular (n = 56) subgroups were compared in these variables through a MANCOVA. RESULTS: Muscular patients show a higher level of general distress, specifically in the anxiety and somatization subscales and a more active coping style, with a tendency of a minor use of humor and a higher number of parafunctional habits, specifically, biting nails, hangnails, and lips. CONCLUSION: We discuss the differences found in order to design the targets of the psychological intervention of temporomandibular patients.  相似文献   
46.
BACKGROUND: Activation recovery intervals (ARIs) and monophasic action potential (MAP) duration are used as measures of action potential duration in beating hearts. However, controversies exist concerning the correct way to record MAPs or calculate ARIs. We have addressed these issues experimentally. OBJECTIVES: To experimentally address the controversies concerning the correct way to record MAPs or calculate ARIs. METHODS: Left ventricular local electrograms were recorded in isolated pig hearts with an exploring electrode grid, with a KCl reference electrode on the left ventricular myocardium, the aortic root, or the left atrium. Local activation was determined from calculated Laplacian electrograms. RESULTS: With the KCl electrode on the aortic root, local electrograms represented local activation. However, with the KCl electrode on the myocardium remote from the exploring electrode, a combined electrogram emerged consisting of local activation recorded from the grid and remote activation recorded from the reference electrode. The remote, inverted monophasic component did not show propagation and did not correlate with the Laplacian complex. When the KCl electrode was placed on the atrium during AV block, remote atrial monophasic components were completely dissociated from local, ventricular deflections. At left ventricular sites with a positive T wave, the Laplacian signal showed that the end of the T wave was caused by remote repolarization. During cooling-induced regional action potential prolongation, the T wave became negative, whereby the positive flank of the T wave remained correlated with repolarization (recorded with a MAP at the same site). CONCLUSIONS: MAPs are recorded from the depolarizing electrode. In both negative and positive T waves, the moment of maximum dV/dt corresponds to local repolarization.  相似文献   
47.
BACKGROUND: Portugal has one of the highest mortality rates from stroke, a high prevalence of hypertension and probably a high salt intake level. AIM: To evaluate Portuguese salt intake levels and their relationship to blood pressure and arterial stiffness in a sample of four different adult populations living in northern Portugal. METHODS: A cross-sectional study evaluating 24-hour urinary excretion of sodium (24 h UNa+), potassium and creatinine, blood pressure (BP), and pulse wave velocity (PWV) as an index of aortic stiffness in adult populations of sustained hypertensives (HT), relatives of patients with previous stroke (Fam), university students (US) and factory workers (FW), in the context of their usual dietary habits. RESULTS: We evaluated a total of 426 subjects, mean age 50 +/- 22 years, 56% female, BMI 27.9+/-5.1, BP 159/92 mmHg, PWV 10.4+/-2.2 m/s, who showed mean 24h UNa+ of 202 +/- 64 mmol/d, corresponding to a daily salt intake of 12.3 g (ranging from 5.2 to 24.8). The four groups were: HT: n = 245, 49 +/- 18 years, 92% of those selected, 69% treated, BP 163/94 mmHg, PWV 11.9 m/s, 24 h UNa+ 212 mmol/d, i.e. 12.4 g/d of salt); Fam: n = 38, 64 +/- 20 years, 57 % of those selected, BP 144/88 mmHg, PWV 10.5 m/s, 24 h UNa+ 194 mmol/d, i.e. 11.1 g/d of salt; US: n = 82, 22 +/- 3 years, 57% of those selected, BP 124/77 mmHg, PWV 8.7 m/s, 24h UNa+ 199 mmol/d, i.e. 11.3 g/d of salt; FW: n = 61, 39 9 years, 47% of those selected, BP 129/79 mmHg, PWV 9.5 m/s, 24 h UNa+ 221 mmol/d, i.e. 12.9 g/d of salt. The ratio of urinary sodium/potassium excretion (1.9 (0.4) was significantly higher in HT than the other three groups. In the 426 subjects, 24h UNa+ correlated significantly (p < 0.01) with systolic BP (r = 0.209) and with PWV (r=0.256) after adjustment for age and BP. Multivariate analysis showed that BP, age and 24h UNa+ correlated independently with PWV taken as a dependent variable. CONCLUSIONS: Four different Portuguese populations showed similarly high mean daily salt intake levels, almost double those recommended by the WHO. Overall, high urinary sodium excretion correlated consistently with high BP levels and appeared to be an independent determining factor of arterial stiffness. These findings suggest that Portugal in general has a high salt intake diet, and urgent measures are required to restrict salt consumption in order to prevent and treat hypertensive disease and to reduce overall cardiovascular risk and events.  相似文献   
48.
The authors studied quality control procedures at human milk banks and nutritional profiles of 909 milk samples (from 195 donors, aged 15 to 45 years) from banked human milk (BHM) in Brasília, Brazil. Number of donations per donor ranged from 1 to > 10 that consisted mostly of mature milk (90.9%) with a mean total energy of 529 +/- 85 kcal/L and a mean total lipid of 22.7 g/L +/- 13.2. Microbiological quality (titrable acidity-Dornic, degrees D) was suitable for infant feeding in 99.2% of samples (< 8 degrees D), ranging from 2 degrees D to 8 degrees D (mean 4.8 +/- 1.4 degrees D). Most BHM (98.1%) samples were dispensed to inpatient infants (1-7 days) diagnosed with respiratory distress (30.1%), prematurity (20.7%), metabolic distress (16.0%), jaundice (14.4%), bacterial infection (6.0%), pneumonia (3.3%), congenital cardiac distress (2.2%), or other conditions (6.2%). Well-motivated mothers and trained staff are serving and sustaining an important life-saving network with long-lasting impact on public health.  相似文献   
49.
BACKGROUND: Coronary vasculopathy is the main cause of cardiac graft failure. Because yearly coronary angiography is invasive in children, a non-invasive method for detecting graft vasculopathy is needed. The aim of this study was to test dobutamine-stress echocardiography in a pediatric population to determine its feasibility, safety and reliability in the detection of graft coronary artery disease. METHODS: Eighteen patients, aged 2 days to 16.8 years at transplantation (mean 8.4 years), underwent 44 dobutamine-stress echocardiography (DSE) exams, at a follow-up of 1.1 to 11.8 years (mean 5.1 years). Selective coronary angiography was performed for comparison. Echocardiographic recordings were obtained in 4 standard views of the left ventricle and measurements carried out within the frames of a 16-segment model. Segmental scores of contractility were obtained for each segment and a total segmental contractility index was calculated at each stage. RESULTS: All patients reached the maximum dose stage. Maximum heart rate was 57% to 90% of predicted maximum. Maximum systolic blood pressure reached 190 mmHg. Segmental scores were normal in 37 and abnormal in 7 cases. Echographic results were concordant with angiography in 82% and discordant in 18% of the cases (4 negative DSEs with minor angiographic lesions, 2 positive DSEs with normal angiography), but there was no significant angiographic lesion with normal DSE. CONCLUSIONS: DSE is a safe and highly feasible non-invasive technique in transplanted children. A normal DSE study successfully predicts the absence of significant coronary artery disease in the post-transplant population.  相似文献   
50.
OBJECTIVE: Kidney transplantation restores renal filtration, although it does not achieve the function of 2 native kidneys, and with time it may involute back to chronic renal failure. We hypothesized that bioelectrical impedance analysis (BIA) might highlight differences for body compartments among kidney transplants (Tx) with different filtration rates. METHODS: Thirty transplantation patients (19 male, 11 female) were studied at 62.4+/-26.6 months postsurgery and were divided into 3 groups: good creatinine clearance (crCl, mL/min/1.73 m2; >65.0), borderline (35.0相似文献   
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