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51.
52.
Allosensitization represents a major barrier to heart transplantation (HTx). We assessed the efficacy and safety of complement inhibition at transplant in highly sensitized heart transplant recipients. We performed a single-center, single-arm, open-label trial (NCT02013037). Patients with panel reactive antibodies (PRA) ≥70% and pre–formed donor-specific antibodies (DSA) were eligible. In addition to standard of care, patients received nine infusions of eculizumab during the first 2 months posttransplant. The primary composite endpoint was antibody-mediated rejection (AMR) ≥pAMR2 and/or left ventricular dysfunction during the first year. Secondary endpoints included hemodynamic compromise, allograft rejection, and patient survival. Twenty patients were included. Median cPRA and mean fluorescence intensity of immunodominant DSA were 95% (90%–97%) and 6250 (5000–10 000), respectively. Retrospective B cell and T cell flow crossmatches were positive in 14 and 11 patients, respectively. The primary endpoint occurred in four patients (20%). Survival at 1 year was 90% with no deaths resulting from AMR. In a prespecified analysis comparing treated patients to matched control patients, we observed a dramatic reduction in the risk of biopsy-proven AMR in patients treated with eculizumab (HR = 0.36, 95% CI = 0.14–0.95, p = .032). Our findings support the prophylactic use of complement inhibition for heart transplantation at high immunological risk. ClinincalTrials.gov, NCT02013037.  相似文献   
53.
Wound‐dressing performances are affected by exudate viscosity, resistance to flow because of gravity, and bodyweight loads, the level of which is related to the body position. Here, we focussed on two dressing properties: (a) Sorptivity—the ability of dressings to transfer exudate away from the wound bed by capillary action—and (b) Durability—the capacity of dressings to maintain their integrity over time and during their removal. Both properties are critically important for avoiding further tissue damage but require the development of new laboratory tests for their measurement. A computer‐controlled phantom of an exuding sacral pressure ulcer has therefore been developed and used to compare the performances of Exufiber (Mölnlycke Health Care) vs an alternative market‐leading dressing. Sorptivity was determined using weight tests, and durability was measured through tensile tests of the used dressings. For a supine configuration, the Exufiber dressing demonstrated ~three times higher sorptivity and better durability, withstanding ~five times greater strain energy than the other product before failure occurred. This work paves the way for quantitative, standardised testing of dressings in all aspects of exudate management. The reported tests are further suitable for testing dressing combinations or how dressings interact with negative pressure wound therapy.  相似文献   
54.
ObjectiveTo examine variation in trajectories of abandoning conventionally fractionated whole‐breast irradiation (CF‐WBI) for adjuvant breast radiotherapy among physician peer groups and the associated cost implications.Data SourcesMedicare claims data were obtained from the Chronic Conditions Data Warehouse for fee‐for‐service beneficiaries with breast cancer in 2011‐2014.Study DesignWe used social network methods to identify peer groups of physicians that shared patients. For each physician peer group in each time period (T1 = 2011‐2012 and T2 = 2013‐2014), we calculated a risk‐adjusted rate of CF‐WBI use among eligible women, after adjusting for patient clinical characteristics. We applied a latent class growth analysis to these risk‐adjusted rates to identify distinct trajectories of CF‐WBI use among physician peer groups. We further estimated potential savings to the Medicare program by accelerating abandonment of CF‐WBI in T2 using a simulation model.Data Collection/Extraction MethodsUse of conventionally fractionated whole‐breast irradiation was determined from Medicare claims among women ≥ 66 years of age who underwent adjuvant radiotherapy after breast conserving surgery.Principal FindingsAmong 215 physician peer groups caring for 16 988 patients, there were four distinct trajectories of abandoning CF‐WBI: (a) persistent high use (mean risk‐adjusted utilization rate: T1 = 94.3%, T2 = 90.6%); (b) decreased high use (T1 = 81.3%, T2 = 65.3%); (c) decreased medium use (T1 = 60.1%, T2 = 44.0%); and (d) decreased low use (T1 = 31.6%, T2 = 23.6%). Peer groups with a smaller proportion of patients treated at free‐standing radiation facilities and a larger proportion of physicians that were surgeons tended to follow trajectories with lower use of CF‐WBI. If all physician peer groups had practice patterns in T2 similar to those in the “decreased low use” trajectory, the Medicare program could save $83.3 million (95% confidence interval: $58.5 million‐$112.2 million).ConclusionsPhysician peer groups had distinct trajectories of abandoning CF‐WBI. Physician composition and setting of radiotherapy were associated with the different trajectories. Distinct practice patterns across the trajectories had important cost implications.  相似文献   
55.
Patterns of neuronal activity in the lumbar spinal cord of the anaesthetized rat were mapped by immunocytochemical localization of the c-fos gene product, Fos protein, at different timepoints following brief noxious stimulation of one hindpaw (20 s immersion in water at 52 degrees C). After 2 h, Fos-immunoreactive neurons were seen mainly in the superficial laminae of the ipsilateral dorsal horn, with maximum somatotopic organization in lamina II. Subcutaneous injection of dilute formalin produced a similar pattern of immunostaining at 2 h, with a greater proportion of Fos-positive neurons in laminae III-VIII than with heat. With a survival time of 8 h following formalin injection, Fos immunoreactivity was virtually absent from the spinal cord. Eight hours after heat stimulation, however, the superficial pattern had given way to the appearance of a population of immunoreactive cells in the deeper laminae. The pattern of this "second wave" of heat-induced Fos-positive cells had a marked contralateral component, and was still present after 24 h, having become even more diffuse and symmetrical. The number of Fos-positive cells seen at 8 h was increased by local anaesthetic blockade of the peripheral nerve after stimulation, and reduced by continuous barbiturate anaesthesia. These findings suggest that the early stages of thermal injury trigger a complex pattern of molecular events within the spinal cord, which are initially monosynaptic and closely related to primary afferent terminal depolarization, and in the longer term the result of an induced pattern of synaptic activity set up within the spinal cord.  相似文献   
56.
The treatment of 17 chronic, unreduced anterior dislocations of the shoulder was reviewed. Eleven women and six men with on average age of 67 years (range 36 to 88 years) were studied. The duration of dislocation averaged 2.3 years (8 weeks to 8 years). Seven patients were treated without surgery despite severe functional deficits, for reasons of health or motivation. Ten were treated with surgery. One patient with preserved joint surfaces underwent open reduction and corticoid transfer to bone graft an eroded anterior glenoid. Nine patients with destroyed articular surfaces underwent unconstrained replacement orthroplosty. Humeral retroversion was increased for stability. The soft tissues were reattached, and rehabilitation was modified as with a repair of recurrent dislocations. Anterior glenoid erosion was often present and required bone grafting to support the glenoid component in four shoulders. Two chronic rotator cuff tears required repair. Nine patients were followed from 2 to 6 years, with an average of 3.9 years. The results were four excellent, four satisfactory, and one unsatisfactory. Although the reconstruction is complex, the surgical results were clearly superior to those of the nonoperative group.  相似文献   
57.
A case is presented of acute intraoperative atelectasis causing profound hypoxaemia in a patient undergoing a combined epidural-general anaesthetic for hip surgery in the lateral position. The pathophysiology of the resultant ventilation-perfusion mis-match and the effects of applied positive end-expiratory pressure in the lateral position are explored. The emergency management is assessed, with emphasis on the role of bronchoscopy in diagnosis and treatment of this rare cause of life-threatening hypoxaemia in the operating room. This patient with risk factors for respiratory complications may have benefited from preoperative bronchoscopy to assist in lung expansion.  相似文献   
58.
Preclinical pharmacokinetics and antitumor activity of imexon   总被引:2,自引:0,他引:2  
Summary Imexon is an aziridine compound originally studied for immune-enhancing effects on lymphocytes. The drug was well-tolerated in humans and was shown to be active in a variety of animal tumor models. Recently, imexon has demonstrated antitumor activity in human multiple myeloma cell linesin vitro. The pharmacokinetics of the compound using a normal phase HPLC assay were studied in normal mice and in dogs with mast cell tumors. Doses of 100 mg/kg given intraperitoneally produced peak plasma levels over 100 (ml in mice and the drug was rapidly eliminated with half lives of 8 minutes ( phase) and 29 minutes ( phase). Only 20% of an oral imexon dose was absorbed in the mouse. In dogs, the and phase half lives ranged from 18–26 minutes and 91–110 minutes, respectively. Peak levels over 100 g/ml were obtained following intravenous doses of 12.5 mg/kg and 25 mg/kg. Imexon was active in mice bearing either P-388 or L-1210 leukemia, but not in mice with B-16 melanoma. These results suggest that cytotoxic drug concentrations can be obtainedin vivo and that imexon is active in lymphoproliferative tumors.  相似文献   
59.
BACKGROUND: New medications that enter the marketplace have been tested almost exclusively in controlled clinical trials conducted in specialty research settings. There is some concern that these carefully selected patient samples may not provide information generalizable to the "real world" clinical population. The purpose of this investigation was to compare results from a large, open-label study of sertraline in the treatment of major depression in the clinical practice setting with pooled results from 2 multicenter, double-blind, placebo-controlled studies conducted in specialty research settings. METHOD: Clinical practice patients (N = 1482), aged 21 to 65 years, from 228 psychiatric clinical practice sites across the United States participated in the open-label treatment study (Clinical Practice sample). Patients who met DSM-III-R criteria for moderate-to-severe unipolar major depression (i.e., had pretreatment Hamilton Rating Scale for Depression [HAM-D] scores >/= 18) were treated for 8 weeks with sertraline in a flexible dosing fashion (50-200 mg daily). Outcomes on the HAM-D and Clinical Global Impressions-Improvement scale (CGI-I) were compared with the pooled results from 2 previously published placebo-controlled, multicenter treatment studies of sertraline in outpatients with major depression (N = 280). The overall response to sertraline in the Clinical Practice sample was compared with the outcome from the research study patient sample (Clinical Research sample). Additionally, comparison of outcomes of patients with common depressive subtypes (double depression, anxious depression, and melancholic ["endogenous"] depression) were examined. RESULTS: The percentage of sertraline-treated patients rated as responders on the CGI-I was significantly higher in the Clinical Practice sample compared with the Clinical Research sample (87% vs. 73%; p <.001). Sertraline was also much better tolerated in the Clinical Practice sample than in the Clinical Research sample as evidenced by significantly lower overall reports of adverse events (9.4% vs. 13.2%; p <.05) and lower patient dropout rates (17.5% vs. 34.3%; p <.01). Among clinical practice patients, sertraline was found to be equally effective in treating endogenous/melancholic and anxious subtypes and only mildly less effective in achieving a response in patients with double depression (chronic low-grade depression with a superimposed major depression). A regression analysis identified older age and double depression as being predictors of a slower time to response. More than 70% of patients who reported nonresponse to previous treatment with fluoxetine or a tricyclic antidepressant responded to sertraline. CONCLUSION: The effectiveness and tolerability of sertraline treatment was found to be significantly better in the Clinical Practice sample, suggesting that the results from controlled studies in research settings may represent an underestimate of the benefits of a drug. More effectiveness research is needed to confirm and extend these findings.  相似文献   
60.
Injury to the long thoracic nerve causing paralysis or weakness of the serratus anterior muscle can be disabling. Patients with serratus palsy may present with pain, weakness, limitation of shoulder elevation, and scapular winging with medial translation of the scapula, rotation of the inferior angle toward the midline, and prominence of the vertebral border. Long thoracic nerve dysfunction may result from trauma or may occur without injury. Fortunately, most patients experience a return of serratus anterior function with conservative treatment, but recovery may take as many as 2 years. Bracing often is tolerated poorly. Patients with severe symptoms in whom 12 months of conservative treatment has failed may benefit from surgical reconstruction. Although many surgical procedures have been described, the current preferred treatment is transfer of the sternal head of the pectoralis major tendon to the inferior angle of the scapula reinforced with fascia or tendon autograft. Many series have shown good to excellent results, with consistent improvement in function, elimination of winging, and reduction of pain.  相似文献   
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