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91.
INTRICATE is a prospective double-blind placebo-controlled feasibility study, assessing the influence of combined vitamin K2 and vitamin D3 supplementation on micro-calcification in carotid artery disease as imaged by hybrid Sodium [18F]Fluoride (Na[18F]F) positron emission tomography (PET)/ magnetic resonance imaging (MRI). Arterial calcification is an actively regulated process and results from the imbalance between calcification promoting and inhibiting factors. Considering the recent advancements in medical imaging, ultrasound (US), PET/MRI, and computed tomography (CT) can be used for the selection and stratification of patients with atherosclerosis. Fifty-two subjects with asymptomatic carotid artery disease on at least one side of the neck will be included in the study. At baseline, an Na[18F]F PET/MRI and CT examination will be performed. Afterwards, subjects will be randomized (1:1) to a vitamin K (400 µg MK-7/day) and vitamin D3 (80 µg/day) or to placebo. At the 3-month follow-up, subjects will undergo a second Na[18F]F PET/MRI and CT scan. The primary endpoint is the change in Na[18F]F PET/MRI (baseline vs. after 3 months) in the treatment group as compared to the placebo arm. Secondary endpoints are changes in plaque composition and in blood-biomarkers. The INTRICATE trial bears the potential to open novel avenues for future large scale randomized controlled trials to intervene in the plaque development and micro-calcification progression.  相似文献   
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93.
PurposeAssessing surgical accuracy and patient-recorded outcome measures for patients fitted with either the OPTY-LINE intramedullary realignment system or the Tomofix plate for medial opening wedge high tibial osteotomy (HTO).Patients and methodsTwo matched case series of patients with symptomatic medial compartment osteoarthritis without other significant knee pathology. One group comprised of 19 patients receiving the Tomofix plate, whereas another comprised of 12 patients receiving the OPTY-LINE intramedullary nail. Patella-centred long leg alignment radiographs were assessed to calculate surgical accuracy in all cases. Patients completed knee injury osteoarthritis outcome scores (KOOS) and osteotomy surgery patient satisfaction questionnaires pre-operatively and at 24 months post-surgery.ResultsAbsolute surgical accuracy at 2 years post-surgery was a mean 4.2 [standard deviation 3.7] for OPTY-LINE versus 9.2 [SD 7.8] for Tomofix (p = 0.11, Mann–Whitney U test). On average, patients in either the OPTY-LINE or Tomofix cohort reported at least a minimal perceptible clinical improvement—minimum average improvement of 15—for all five KOOS themes. No significant difference in change of KOOS scores over time or patient satisfaction levels were observed between the two cohorts.ConclusionThe OPTY-LINE device for HTO performs to a similar level as the Tomofix device. Surgical accuracy data are promising for OPTY-LINE, but does not seem to readily translate into difference in patient-reported outcomes compared to Tomofix. Even longer follow-up periods, to measure survival rates, and true randomised trials on larger samples can elucidate if there is a benefit for using one device over the other.  相似文献   
94.
AimRates of simultaneous liver and kidney transplantation (SLKT) have increased, but indications for SLKT remain poorly defined. Additional data are needed to determine which patients benefit from SLKT to best direct use of scarce donor kidneys.MethodsData were extracted from the Australia and New Zealand Dialysis and Transplant Registry (ANZDATA) database for all SLKT performed until the end of 2017. Patients were divided by pretransplant dialysis status into no dialysis before SLKT (preemptive kidney transplant) and any dialysis before SLKT (nonpreemptive). Baseline characteristics and outcomes were compared.ResultsBetween 1989 and 2017, inclusive, 84 SLKT procedures were performed in Australia, of which 24% were preemptive. Preemptive and nonpreemptive SLKT recipients did not significantly differ in age (P = .267), sex (P = .526), or ethnicity (P = .870). Over a median follow-up time of 4.5 years, preemptively transplanted patients had a statistically equivalent risk of kidney graft failure (hazard ratio (HR) 1.83, 95% confidence interval [CI]: 0.36-12.86, P = .474) and all-cause mortality (HR 1.69, 95% CI: 0.51-5.6, P = .226) compared to nonpreemptive patients. Overall, 1- and 5-year survival rates for all SLKTs were 92% (95% CI: 86-96) and 60% (95% CI: 45-75), respectively.ConclusionKidney graft and overall patient survival were similar between patients with preemptive kidney transplant and those who were dialysis dependent.  相似文献   
95.
Evidence from animal models suggests that undercarboxylated osteocalcin (ucOC) is involved in muscle mass maintenance and strength. In humans, the ucOC to total (t)OC ratio may be related to muscle strength and perhaps physical function and falls risk, but data are limited. We tested the hypothesis that ucOC and ucOC/tOC ratio are associated with muscle function (muscle strength and physical function) in older women and 15-year falls-related hospitalizations. Serum tOC and ucOC were assessed in 1261 older women (mean age 75.2 ± 2.7 years) forming the Perth Longitudinal Study of Aging Women (1998 to 2013). Timed-up-and-go (TUG) and grip strength were assessed at baseline and at 5 years. Falls-related hospitalizations (14.5-year follow-up) were captured by the Hospital Morbidity Data Collection, via the Western Australian Data Linkage System. At baseline, women with higher ucOC/tOC ratio (quartile 4) had slower TUG performance compared with quartile 1 (~0.68 seconds, p < .01). Grip strength and 5-year change of TUG and grip were not different (p > .05) between quartiles. Fear of falling limiting house, outdoor, and combined activities was significantly different across quartiles (p < .05). Higher ucOC/tOC was significantly associated with poorer TUG performance at baseline and 5-year change in performance, increased walking aid use, and fear of falling (all p < .05). Higher ucOC was related to lower grip strength at baseline (p < .05) but not 5-year change in strength. Those with the highest ucOC/tOC had greater falls-related hospitalizations (unadjusted log rank, p = .004) remaining significant after adjusting for key variables (hazard ratio [HR] = 1.31, 95% confidence interval [CI] 1.09–1.57, p = .004). We identified a large proportion of older women with high ucOC/tOC ratio who had reduced physical function, including its long-term decline and increased risk of falls-related hospitalizations. Early identification of women at higher risk can enable prevention and intervention strategies to occur, reducing risk for injurious falls. © 2020 American Society for Bone and Mineral Research (ASBMR)..  相似文献   
96.
97.
 Nitric oxide (NO) has been implicated as a modulator of the vascular effects of angiotensin II (ANG II) in the kidney. We used a NO-sensitive microelectrode to study the effect of ANG II on NO release, and to determine the effect of selective inhibition of the ANG II subtype I receptor (AT1) with losartan (LOS) and candesartan (CAN). NO release from isolated and perfused renal resistance arteries was measured with a porphyrin-electroplated, carbon fiber. The vessels were microdissected from isolated perfused rat kidneys and perfused at constant flow and pressure in vitro. The NO-electrode was placed inside the glass collection cannula to measure vessel effluent NO concentration. ANG II stimulated NO release in a dose-dependent fashion: 0.1 nM, 10 nM and 1000 nM ANG II increased NO-oxidation current by 85±18 pA (n = 11), 148±22 pA (n = 11), and 193±29 pA (n = 11), respectively. These currents correspond to changes in effluent NO concentration of 3.4±0.5 nM, 6.1±1.1 nM, and 8.2±1.3 nM, respectively. Neither LOS (1 μM) nor CAN (1 nM) significantly affected basal NO production, but both AT1-receptor blockers markedly blunted NO release in response to ANG II (10 nM): 77±6% inhibition with LOS (n = 8) and 63±9% with CAN (n = 8). These results are the first to demonstrate that ANG II stimulates NO release in isolated renal resistance arteries, and that ANG II-induced NO release is blunted by simultaneous AT1-receptor blockade. Our findings suggest that endothelium-dependent modulation of ANG II-induced vasoconstriction in renal resistance arteries is mediated, at least in part, by AT1-receptor-dependent NO release. Received: 24 September 1997 / Accepted: 20 October 1997  相似文献   
98.
The authors describe their experience with maintenance electroconvulsive therapy administered to 10 patients, using an abbreviated or a full maintenance schedule. Recommendation for either form of treatment was made on clinical grounds. Patients with major depressive episodes with delusional features appear to respond best to maintenance ECT.  相似文献   
99.
Summary The polycyclic aromatic hydrocarbon 7,12-dimethylbenz(a)anthracene (DMBA) is a metabolism-dependent procarcinogen whose tumorigenicity is modified by dietary and endocrine manipulationsin vivo. DMBA initiates molecular and cellular alterations in the mammary tissue, while dietary components and estrogens affect the post-initiational phase of tumorigenic transformation. The mechanism(s) responsible for modulation of tumorigenic transformation remain unclear. This study examines the effects of selected tumor suppressing agents and estradiol (E2) metabolites onin vitro DMBA carcinogenesis utilizing a newly established mouse mammary epithelial cell line C57/MG. Alteration in DNA repair synthesis, metabolism of E2 via the C2- and C16-hydroxylation pathways, and acquisition of anchorage-independent growth were utilized as molecular, endocrine, and cellular biomarkers to quantitate the cellular transformation by DMBA and its modulation by tumor suppressing agents and E2 metabolites. A single 24 hr exposure of 0.78 µM DMBA to C57/MG cells resulted in a 193.9% increase in DNA repair synthesis and a 73.1% decrease in C2/C16 hydroxylation of E2. The DMBA treated C57/MG cells also exhibited increased anchorage-independencein vitro prior to tumorigenesisin vivo. A simultaneous treatment of cells with DMBA and with the highest non-cytotoxic doses of the tumor suppressing agents 5 µM N-(4-hydroxyphenyl) retinamide (HPR), 50 µM indole-3-carbinol (I3C), or 1 µM tamoxifen (TAM) resulted in a 35.6% to 63.9% decrease in DNA repair synthesis, a 23.8% to 1347.6% increase in C2/C16 hydroxylation of E2, and a 53.8% to 72.4% decrease in anchorage-independent growth. The E2 metabolites at the highest non-cytotoxic doses of 0.76 µM estrone (E1), 0.69 µM 2-hydroxyestrone (2-OHE1), and 0.66 µM 2-methoxyestrone (2-MeOHE1) suppressed DMBA-induced DNA repair synthesis by 56.0% to 68.8%. These tumor suppressing agents and E2 metabolites also effectively suppressed post-initiational, anchorage-independent growth by 24.9% to 72.4%. These results indicate that DMBA induces cellular transformation in part by causing DNA damage, altering C2/C16 hydroxylation in favor of C16-hydroxylation, and inducing anchorage-independent growth prior to tumor development. Effective downregulation of these genotoxic, endocrine and proliferative end points by prototypic tumor suppressing agents and by E2 metabolites generated via the C2-hydroxylation pathway suggest that these agents may influence mammary tumorigenesis by inhibiting early occurring initiational and/or post initiational events.Abbreviations DMBA 7,12-dimethylbenz(a)anthracene - HPR N-(4-hydroxyphenyl) retinamide - I3C indole-3-carbinol - TAM tamoxifen - E2 17-estradiol - E1 estrone - 2-OHE1 2-hydroxyestrone - 2-MeOHE1 2-methoxyestrone - 16-OHE1 16-hydroxyestrone - E3 estriol - DME/F12 Dulbecco's modified Eagle's medium - F12 Ham's medium - HU hydroxyurea - PBS phosphate buffered saline - NaOH sodium hydroxide - SDS sodium dodecyl sulfate - TCA trichloroacetic acid - [C2-3H] E2 estradiol labeled at C2 position - [C16-3H] E2 estradiol labeled at C16 position - ANOVA analysis of variance  相似文献   
100.
P M Marzuk  K Tardiff  A C Leon  M Stajic  E B Morgan  J J Mann 《JAMA》1990,263(2):250-256
We determined the prevalence of recent cocaine and alcohol use among motor vehicle fatalities occurring in New York, NY, from 1984 through 1987. Recent cocaine use was detected at autopsy in 18.2% of the sample and no significant difference between drivers (20.0%) and passengers (13.9%) was found. Both alcohol and cocaine metabolites were found in 10.0% of cases tested. The prevalence of cocaine metabolites or alcohol detected in driver fatalities aged 16 through 45 years did not change significantly when the period prior to the widespread availability of "crack" cocaine (1984 through 1985) was compared with the period immediately following the introduction of crack cocaine (1986 through 1987). Additional studies are needed both to elucidate the association between cocaine use and these fatalities and to determine the value of screening persons seriously injured in traffic accidents in areas where such drug use is endemic.  相似文献   
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