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91.
Desensitization for sulfasalazine skin rash   总被引:1,自引:0,他引:1  
Thirteen patients with inflammatory bowel disease and a documented allergy to sulfasalazine, manifested by skin rash with or without fever, were enrolled in a sulfasalazine-desensitization protocol. Twelve patients were successfully desensitized by using two concentrations of a liquid suspension of sulfasalazine. Four of thirteen patients developed a rash during the protocol. Although one patient refused further attempts at desensitization, the remainder completed the regimen successfully, despite recurrence of the rash on two occasions in one patient. No predilection to either fast or slow acetylator phenotype was found. This simple and convenient tolerance induction regimen may be used safely to desensitize most patients with sulfasalazine allergy manifested by skin rash with or without fever, despite recurrence of the rash during tolerance induction. Patients with serious reactions to sulfasalazine, such as agranulocytosis, toxic epidermal necrolysis, or fibrosing alveolitis, are not candidates for desensitization.  相似文献   
92.
OBJECTIVE: Many patients with functional (noncardiac) chest pain exhibit both hypersensitivity and motor dysfunction of the esophageal wall. We aimed to determine whether the sensory or motor dysfunction plays an important role in the pathogenesis of chest pain. METHODS: We performed graded balloon distentions of the esophagus using impedance planimetry in 16 consecutive patients with chest pain and otherwise normal cardiac and esophageal evaluations and in 13 healthy controls. In those patients who experienced chest pain with balloon distention, the test was repeated after atropine was given. Sensory and biomechanical parameters were measured. RESULTS: Balloon distention reproduced typical chest pain in 13/16 patients (81%) and at lower (p < 0.01) sensory thresholds than controls. Pain was reproduced in all 13 patients and at lower (p < 0.05) sensory thresholds after atropine. Also, after atropine, the esophageal cross-sectional area and wall tension increased (p < 0.05), the tension/strain association shifted to the right (p < 0.05), and reactivity decreased (p < 0.002) relative to results before atropine or in healthy controls (i.e., the esophageal wall relaxed and became more deformable). CONCLUSIONS: Even after relaxing the esophageal wall, most patients experienced chest pain and at lower sensory thresholds. Hence, hyperalgesia rather than motor dysfunction appears to be the predominant mechanism for functional chest pain of esophageal origin.  相似文献   
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Four patients who had stenosis of a single major coronary artery which was treated by percutaneous transluminal coronary angioplasty are described. Three had exercise induced myocardial ischaemia complicated by ventricular tachycardia, fibrillation, and sinus bradycardia, respectively. Asystole developed in a fourth patient who had spontaneous chest pain. After successful percutaneous transluminal coronary angioplasty these arrhythmias did not recur spontaneously or on treadmill exercise testing. Percutaneous coronary angioplasty can be effective in preventing arrhythmias complicating acute myocardial ischaemia secondary to stenosis of a single major coronary artery.  相似文献   
98.
The development of left ventricular cardiomyocyte hypertrophy in response to increased hemodynamic load and neurohormonal stress is initially a compensatory response. However, persistent stress eventually leads to dilated heart failure, which is a common cause of heart failure in human hypertensive and valvular heart disease. We have recently reported that Rho-associated coiled-coil containing protein kinase 1 (ROCK1) homozygous knockout mice exhibited reduced cardiac fibrosis and cardiomyocyte apoptosis, while displaying a preserved compensatory hypertrophic response to pressure overload. In this study, we have tested the effects of ROCK1 deficiency on cardiac hypertrophy, dilation, and dysfunction. We have shown that ROCK1 deletion attenuated left ventricular dilation and contractile dysfunction, but not hypertrophy, in a transgenic model of Gαq overexpression-induced hypertrophy which represents a well-characterized and highly relevant genetic mouse model of pathological hypertrophy. Although the development of cardiomyocyte hypertrophy was not affected, ROCK1 deletion in Gαq mice resulted in a concentric hypertrophic phenotype associated with reduced induction of hypertrophic markers indicating that ROCK1 deletion could favorably modify hypertrophy without inhibiting it. Furthermore, ROCK1 deletion also improved contractile response to β-adrenergic stimulation in Gαq transgenic mice. Consistent with this observation, ROCK1 deletion prevented down-regulation of type V/VI adenylyl cyclase expression, which is associated with the impaired β-adrenergic signaling in Gαq mice. The present study establishes for the first time a role for ROCK1 in cardiac dilation and contractile dysfunction.  相似文献   
99.
Most kidneys from potential elderly circulatory death (DCD) donors are declined. We report single center outcomes for kidneys transplanted from DCD donors over 70 years old, using preimplantation biopsy Remuzzi grading to inform implantation as single or dual transplants. Between 2009 and 2012, 43 single transplants and 12 dual transplants were performed from elderly DCD donors. Remuzzi scores were higher for dual than single implants (4.4 vs. 3.4, p < 0.001), indicating more severe baseline injury. Donor and recipient characteristics for both groups were otherwise similar. Early graft loss from renal vein thrombosis occurred in two singly implanted kidneys, and in one dual‐implanted kidney; its pair continued to function satisfactorily. Death‐censored graft survival at 3 years was comparable for the two groups (single 94%; dual 100%), as was 1 year eGFR. Delayed graft function occurred less frequently in the dual‐implant group (25% vs. 65%, p = 0.010). Using this approach, we performed proportionally more kidney transplants from elderly DCD donors (23.4%) than the rest of the United Kingdom (7.3%, p < 0.001), with graft outcomes comparable to those achieved nationally for all deceased‐donor kidney transplants. Preimplantation biopsy analysis is associated with acceptable transplant outcomes for elderly DCD kidneys and may increase transplant numbers from an underutilized donor pool.  相似文献   
100.

Background

Internet-based data collection relies on well-designed and validated questionnaires. The theory behind designing and validating questionnaires is well described, but few practical examples of how to approach validation are available in the literature.

Objective

We aimed to validate data collected in an ongoing Internet-based longitudinal health study through direct visits to participants and recall of their health records. We demonstrate that despite extensive pre-planning, social desirability can still affect data in unexpected ways and that anticipation of poor quality data may be confounded by positive validation.

Methods

Dogslife is a large-scale, Web-based longitudinal study of canine health, in which owners of Labrador Retrievers were recruited and questioned at regular intervals about the lifestyle and health of their dogs using an Internet-based questionnaire. The Dogslife questionnaire predominantly consists of closed-answer questions. In our work, two separate validation methodologies were used: (1) direct interviews with 43 participants during visits to their households and (2) comparison of owner-entered health reports with 139 historical health records.

Results

Our results indicate that user-derived measures should not be regarded as a single category; instead, each measurement should be considered separately as each presents its own challenge to participants. We recommend trying to ascertain the extent of recall decay within a study and, if necessary, using this to guide data collection timepoints and analyses. Finally, we recommend that multiple methods of communication facilitate validation studies and aid cohort engagement.

Conclusions

Our study highlighted how the theory underpinning online questionnaire design and validation translates into practical data issues when applied to Internet-based studies. Validation should be regarded as an extension of questionnaire design, and that validation work should commence as soon as sufficient data are available. We believe that validation is a crucial step and hope our suggested guidelines will help facilitate validation of other Internet-based cohort studies.  相似文献   
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