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71.

Background

Originally reported to occur predominantly in younger women, idiopathic pulmonary arterial hypertension (IPAH) is increasingly diagnosed in elderly patients. We aimed to describe the characteristics of such patients and their survival under clinical practice conditions.

Methods

Prospective registry in 28 centers in 6 European countries. Demographics, clinical characteristics, hemodynamics, treatment patterns and outcomes of younger (18–65 years) and elderly (> 65 years) patients with newly diagnosed IPAH (incident cases only) were compared.

Results

A total of 587 patients were eligible for analysis. The median (interquartile, [IQR]) age at diagnosis was 71 (16) years. Younger patients (n = 209; median age, 54 [16] years) showed a female-to-male ratio of 2.3:1 whereas the gender ratio in elderly patients (n = 378; median age, 75 [8] years) was almost even (1.2:1). Combinations of PAH drugs were widely used in both populations, albeit less frequently in older patients. Elderly patients were less likely to reach current treatment targets (6 min walking distance > 400 m, functional class I or II). The survival rates 1, 2, and 3 years after the diagnosis of IPAH were lower in elderly patients, even when adjusted for age- and gender-matched survival tables of the general population (p = 0.006 by log-rank analysis).

Conclusions

In countries with an aging population, IPAH is now frequently diagnosed in elderly patients. Compared to younger patients, elderly patients present with a balanced gender ratio and different clinical features, respond less well to medical therapy and have a higher age-adjusted mortality. Further characterization of these patients is required.Clinical trials registration: NCT01347216.  相似文献   
72.
73.
Since biomechanical studies have shown that the medial patellofemoral ligament (MPFL) is the main restraint against lateral patella displacement, reconstruction of the MPFL has become an accepted surgical technique to restore patellofemoral stability. Recently, various procedures have been described that address reconstruction of the medial patellofemoral complex. We present a technique, where the MPFL is reconstructed anatomically to restore physiological kinematics and stability, using a free gracilis tendon autograft.  相似文献   
74.
75.
We report the case of a 33-year-old man admitted to a psychiatric hospital because of paranoid schizophrenia. The man was found dead lying in his bed with the face pressed against a pillow and with elevated buttocks. The autopsy did not reveal a cause of death. The histological findings displayed the signs of the haemorrhagic–dysoric syndrome with acute emphysema; these findings are pathognomonic of obstructive asphyxia. The adverse effects of the neuroleptics demonstrated by the toxicological findings may have accelerated the loss of consciousness and facilitated the unusual position of the body. On the basis of the clinical history, the autopsy findings, the histological features and the toxicological results, asphyxia due to smothering was diagnosed as the cause of death.  相似文献   
76.
77.
The sedative and anesthetic-sparing ability of the alpha2-adrenergic agonist dexmedetomidine is well documented. In this study, we identified the effects of halothane, with and without dexmedetomidine, on hemodynamic and electroencephalographic (EEG) variables and quantified the concentration of halothane resulting in various anesthetic depth indices mediated through the central nervous system (CNS) in chronically instrumented cats. Halothane was given alone or after dexmedetomidine (15 microg/kg p.o.). In both groups, four indices of anesthetic depth--minimum alveolar anesthetic concentration (MAC; no movement to noxious stimuli), MAC(BAR) (no autonomic response to noxious stimuli), MAC(BS) (EEG burst suppression), and MAC(ISOELECTRIC) (EEG isoelectricity)--were determined. Halothane decreased arterial blood pressure, heart rate, and higher frequency components of the EEG before the onset of burst suppression and isoelectricity. Dexmedetomidine pretreatment augmented the actions of halothane on arterial pressure, heart rate, and the EEG. Dexmedetomidine reduced the halothane concentrations resulting in MAC (from 1.22% +/- 0.06% to 0.89% +/- 0.08%) and MAC(BAR) (from 1.81% +/- 0.05% to 1.1% +/- 0.10%), but not those resulting in MAC(BS) (3.01% +/- 0.17% vs 3.14% +/- 0.10%) or MAC(ISOELECTRIC) (4.39% +/- 0.26% vs 4.65% +/- 0.12%). These results suggest that dexmedetomidine does not alter various CNS-mediated indices of anesthetic action to equivalent degrees and that there are dissimilar degrees of an anesthetic-sparing action at different levels of the neuraxis. IMPLICATIONS: The anesthetic adjuvant dexmedetomidine seems to differentially alter central nervous system-mediated indices of anesthetic action. Lower brainstem or spinal determinants of anesthetic depth (movement and hemodynamic responses) are more attenuated than those of higher brain functions, such as the electroencephalogram.  相似文献   
78.
Halothane attenuates the alterations in arterial pressure (BP) and heart rate (HR) produced by central nervous svstem (CNS) stimulation. We examined the effects of the alpha2-adrenergic agonist dexmedetomidine, with and without halothane, on cardiovascular regulation during CNS pressor site stimulation in chronically instrumented cats. Stimuli trains via bipolar stimulating electrodes in the hypothalamus and reticular formation elicited pressor responses. Dexmedetomidine-induced (15 microg/kg PO) bradycardia was greater in the presence of halothane. CNS stimulation increased BP and HR, which were dose-dependently attenuated by halothane (hypothalamic stimulation 71 +/- 9 mm Hg at control, 25 +/- 5 and 15 +/- 3 mm Hg at 1.0% and 1.5% halothane, respectively). Although dexmedetomidine alone did not alter pressor responses, halothane plus dexmedetomidine attenuated pressor responses in a potentially synergistic fashion (hypothalamic stimulation 67 +/- 8 mm Hg at control, 2 +/- 1 and 1 +/- 0.4 mm Hg at 1.0% and 1.5% halothane, respectively). These results suggest differences in the disruptive effects of CNS-mediated cardiovascular responses by halothane and dexmedetomidine, and that dexmedetomidine has an anesthetic-sparing effect on these CNS-mediated cardiovascular control mechanisms, potentiating the depressant effect of halothane. IMPLICATIONS: A new potential anesthetic adjunct, dexmedetomidine, does not attenuate brain-mediated increases in blood pressure, but the combination of dexmedetomidine and the anesthetic halothane acts to modulate central cardiovascular responses.  相似文献   
79.

Background/purpose

Variation exists among pediatric surgeons in the management of pediatric appendicitis. The goal of this study was to determine current practice patterns and provide a foundation for evidence-based outcome studies that would standardize patient care.

Methods

Members of the American Pediatric Surgical Association (APSA) were surveyed. Data included preference of imaging, timing of operation, and opinions on interval appendectomy. Intraoperative principles surveyed included use of cultures, antibiotic irrigation, transperitoneal drains, and method of wound closure. Spectrum and duration of antibiotic coverage were assessed, as were discharge criteria.

Results

Survey response was 70%. A majority prefers computerized tomographic (CT) imaging and favors interval appendectomy in appropriate candidates. Seventy percent indicate a stable child with suspected appendicitis would be operated on in a semiurgent manner rather than emergently in their practice. Discrepancy exists in the type and duration of antibiotic coverage, impact of clinical parameters on antibiotic use, and utility of discharge criteria.

Conclusions

This study consolidates current opinions on appropriate management of pediatric appendicitis, providing a foundation for evidence-based outcome studies capable of bringing conformity to the management of this surgical disease. Such studies would establish clinical practice guidelines that optimize resource utilization while maintaining quality care.  相似文献   
80.
OBJECTIVE: To study the relationship of C677T and A1298C polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) gene to toxicity and efficacy of methotrexate (MTX) in patients with juvenile idiopathic arthritis (JIA). METHODS: Single nucleotide polymorphisms of the MTHFR gene were investigated by polymerase chain reaction and restriction enzyme analysis of DNA extracted from peripheral blood cells. The fasting plasma homocysteine concentration was analyzed by enzyme immunoassay. Clinical data of 58 patients with JIA treated with MTX were analyzed retrospectively. RESULTS: The 1298A/A genotype was present in 31 patients, 1298C/C in 4 patients, and 21 patients were heterozygous. The 677C/C genotype was present in 29 patients, 677 T/T in 3 patients, and 26 patients were heterozygous. In patients who presented the C allele of the A1298C polymorphism, improvement with respect to the number of swollen joints, the number of tender joints, and a decrease in erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) levels occurred more frequently than in 1298 A/A homozygous patients (p < 0.05 for ESR, p < 0.01 for CRP, chi-square test). There was no relationship between the C677T polymorphism and the efficacy of MTX treatment. Forty-two adverse events were noted in 26 patients; gastrointestinal symptoms were most common (n = 20), followed by elevated serum levels of transaminases (n = 19) and hair loss (n = 3). There was no cytopenia. Patients with the heterozygous genotype 677C/T exhibited adverse events more frequently than patients with the homozygous C/C genotype (65% vs 31%; p < 0.05, chi-square test). The A1298C polymorphism, however, was not associated with occurrence of adverse events. Plasma homocysteine was elevated in 6 patients with up to 16.9 mmol/l. No association was found to a specific genotype or to adverse events. CONCLUSION: These preliminary data suggest an association of the MTHFR 677C/C polymorphism to a higher tolerability of MTX, and of the 1298A/A to lower clinical efficacy of MTX therapy in JIA.  相似文献   
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