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Introduction: A recent Rasch analysis performed on the Hammersmith Functional Motor Scale—Expanded (HFMSE) in patients with spinal muscular atrophy (SMA) identified issues impacting scale validity, redundant items, and disordered thresholds on some items. Methods: We modified the HMFSE scoring based on the Rasch analysis and on expert consensus to establish whether the traditional scoring overestimated the number of patients with changes within 2 points from baseline. Data were collected retrospectively from multicenter data sets in 255 type 2 and 3 SMA patients. Results: The mean 12‐month changes using the new and the traditional scoring system did not differ significantly (P > 0.05). The numbers of patients who improved or decreased by >2 points were also similar. Conclusions: The presence of outliers using the traditional scoring system was not due to overestimation of changes in activities that were tested bilaterally or to discrepancies in the scoring hierarchy of individual items. Muscle Nerve 52:435–437, 2015  相似文献   
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Although multiple recent studies have shown that myocardial contrast echocardiography (MCE) reliably differentiates between regional stunning and necrosis after acute myocardial infarction (AMI), prognosis is more closely related to measures of global left ventricular systolic function. One hundred fifteen patients underwent baseline wall motion assessment and MCE 2 days after admission and follow-up echocardiography a mean of 69 days later. Good agreement was found between perfusion score index and follow-up wall motion score index, indicating that MCE performed early after anterior wall AMI may be clinically useful in routine post-AMI risk stratification.  相似文献   
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Culture-based preemptive therapy with ganciclovir was shown to reduce the incidence of cytomegalovirus (CMV) disease after bone marrow transplantation (BMT). Culture techniques did not detect CMV in 12% to 13% of patients before the onset of CMV disease. In a prospective study, 71 patients either received preemptive therapy based on polymerase chain reaction (PCR) technique (37 patients) or on culture assays (34 patients). In both groups, therapy was continued until clinical signs disappeared and PCR negativity was documented. Twenty- two patients in the PCR group and 15 patients in the culture group received antiviral therapy. PCR allowed detection of the virus (median day, +32 v day +49; P = .006) and introduction of antiviral therapy (median day, +44 v day +54; P = .02) earlier than did culture assays. The incidences of CMV disease (2 of 37 v 8 of 34 in PCR group v culture group, respectively; P = .02) and CMV-associated mortality (0 of 37 v 5 of 34 in PCR group v culture group, respectively; P = .02) were decreased, and the duration of ganciclovir therapy (P < .001) was shorter in the PCR-monitored group. Incidence and median duration of severe neutropenia (less than 500/microL) were lower in the PCR group (two v eight episodes, P = .02; median duration, 1.5 v 5 days, P = .04), as was the incidence of nonviral infections during/after antiviral therapy (2 of 37 v 9 of 34; P = .012). Thus, preemptive therapy based on more sensitive detection methods such as the PCR assay reduces the incidence of CMV disease and CMV-related mortality. Additionally, stopping and withholding antiviral therapy in a PCR- negative patient is safe and allows reduction of the duration and side effects of antiviral therapy.  相似文献   
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Ivy  SP; Olshefski  RS; Taylor  BJ; Patel  KM; Reaman  GH 《Blood》1996,88(1):309-318
Clinical drug resistance may be attributed to the simultaneous selection and expression of genes modulating the uptake and metabolism of chemotherapeutic agents. P-glycoprotein (P-gp) functions as a membrane-associated drug efflux pump whose increased expression results in resistance to anthracyclines, epipodophyllotoxins, vinca alkaloids, and some alkylating agents. This type of resistance occurs as both de novo and acquired resistance to therapy for leukemia. We have studied P- gp expression and function in childhood acute leukemias by developing a series of doxorubicin- and vincristine-selected CEM, T-cell lymphoblastoid cell lines that recapitulate the low levels of expression and resistance seen clinically. These cell lines have been used to develop flow cytometric assays for the semiquantitative measurements of P-gp expression with the MRK16 monoclonal antibody and P-gp function using the enhanced retention of rhodamine 123 in the presence of verapamil, a resistance modulator. Kolmogorov-Smirnov statistics, represented by the D measurement, are used to determine the difference in level of P-gp expression by comparing MRK16 staining to an IgG2a isotype control. When D is > 0.09, there is an excellent correlation (R = 0.82) between P-gp expression and function. The evaluation of 107 bone marrow specimens from 84 children with lymphoblastic or myelogenous leukemia showed a statistically significant (P = .004) increase in P-gp function at relapse. P-gp expression at relapse, however, approached but did not reach a significant level (P = .097). Using this methodology, we can identify patients with levels of P-gp expression and function that we can define clinically, as well as children with discordant multidrug resistance phenotypes. This study supports the role of P-gp-mediated drug resistance in childhood leukemia and confirms that P-gp expression and function are measurable in their leukemic blasts. These assays provide the means for the in vitro testing of resistance modulators and the monitoring of in vivo response to treatment with these agents.  相似文献   
169.
BACKGROUND/AIMS: Hepatic steatosis is caused by the complex interaction of host and viral factors, such as metabolic syndrome (MS), alcoholism and HCV genotype, and in HIV-HCV co-infected patients, antiretroviral therapy may also play a role. A large population of patients from the AIDS Pegasys Ribavirin International Co-infection Trial (APRICOT) had paired liver biopsies interpreted and graded for steatosis along with lipid measurements and anthropometric data. METHODS: We analyzed these patients to determine the prevalence of steatosis, baseline factors associated with steatosis, effect of steatosis in HCV therapy efficacy and the impact of anti-HCV treatment on steatosis. RESULTS: A total of 65/283 (23%) patients with paired biopsies were positive for steatosis. Patients with steatosis were significantly more likely to have HCV genotype 3, bridging fibrosis/cirrhosis, higher HCV RNA levels, increased triglycerides and lower cholesterol levels. The only different body measurement was neck circumference which was greater in patients with steatosis and significantly decreased from baseline during the study. Hip circumference was predictive of steatosis at baseline. CONCLUSIONS: Factors associated to the metabolic syndrome are important in co-infected patients. Treatment outcome affected steatosis in that viral eradication reduced steatosis in genotype 3 patients, but altogether steatosis did not affect efficacy of treatment in any genotype.  相似文献   
170.
Virus-host interaction in chronic hepatitis B virus infection   总被引:3,自引:0,他引:3  
The clearance of HBV-infected cells from the liver is probably dependent on an interplay between the interferon system and the cellular limb of the host immune response. Although the importance of the nucleocapsid proteins as targets for sensitized cytotoxic T cells is established in chronic HBV infection, further studies are needed during the early phase of acute HBV infection. The relative importance of pre S sequences as inducers and targets of the virus neutralizing humoral immune response is becoming established, but their precise place will await the development of in vitro models of hepadnavirus infection and precise definition of the mechanism of viral uptake. Our understanding of the mechanisms underlying the development of chronic HBV infection is still incomplete. When this occurs in adult life, deficient production of alpha interferon and suppression of the ability of the host to respond to interferon are probably important factors, and the role of suppression of the humoral response remains to be determined. In the neonate, specific suppression of the cell-mediated immune response, perhaps because of exposure to soluble HBe antigen or to modulating quantities of maternally derived antinucleocapsid antibodies at a time when the immune system is "immature," may be involved. In each of these postulated mechanisms the virus has neutralized one important host defense. Increasing the response rate to therapy with interferon or synthetic antiviral compounds will depend on identifying the cause in each patient and devising specific therapies to reverse the host-virus balance in favor of the host defenses.  相似文献   
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