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51.
The prevalence of type 2 diabetes in youth has increased substantially, yet the genetic underpinnings remain largely unexplored. To identify genetic variants predisposing to youth-onset type 2 diabetes, we formed ProDiGY, a multiethnic collaboration of three studies (TODAY, SEARCH, and T2D-GENES) with 3,006 youth case subjects with type 2 diabetes (mean age 15.1 ± 2.9 years) and 6,061 diabetes-free adult control subjects (mean age 54.2 ± 12.4 years). After stratifying by principal component–clustered ethnicity, we performed association analyses on ∼10 million imputed variants using a generalized linear mixed model incorporating a genetic relationship matrix to account for population structure and adjusting for sex. We identified seven genome-wide significant loci, including the novel locus rs10992863 in PHF2 (P = 3.2 × 10−8; odds ratio [OR] = 1.23). Known loci identified in our analysis include rs7903146 in TCF7L2 (P = 8.0 × 10−20; OR 1.58), rs72982988 near MC4R (P = 4.4 × 10−14; OR 1.53), rs200893788 in CDC123 (P = 1.1 × 10−12; OR 1.32), rs2237892 in KCNQ1 (P = 4.8 × 10−11; OR 1.59), rs937589119 in IGF2BP2 (P = 3.1 × 10−9; OR 1.34), and rs113748381 in SLC16A11 (P = 4.1 × 10−8; OR 1.04). Secondary analysis with 856 diabetes-free youth control subjects uncovered an additional locus in CPEB2 (P = 3.2 × 10−8; OR 2.1) and consistent direction of effect for diabetes risk. In conclusion, we identified both known and novel loci in the first genome-wide association study of youth-onset type 2 diabetes.  相似文献   
52.
ObjectiveTo assess the feasibility of enrollment and collecting patient-reported outcome (PRO) data as part of routine clinical urologic care for bladder and prostate cancer patients and examine overall patterns and racial variations in PRO use and symptom reports over time.Subjects/Patients and MethodsWe recruited 76 patients (n = 29 Black and n = 47 White) with prostate or bladder cancer at a single, comprehensive cancer center. The majority of prostate cancer patients had intermediate risk (57%) disease and underwent either radiation or prostatectomy. Over half (58%) of bladder cancer patients had muscle invasive disease and underwent cystectomy.Patients were asked to complete PRO symptom surveys using their preferred mode [web- or phone-based interactive voice response (IVR)]. Symptom summary reports were shared with providers during visits. Surveys were completed at 3 time points and assessed urinary, sexual, gastrointestinal, anxiety/depression, and sleep symptoms. Feasibility of enrollment and survey completion were calculated, and linear mixed effects models estimated differences in outcomes by race and time.ResultsSixty three percent of study participants completed all PRO measures at all 3 time points. Black patients were more likely to select IVR as their survey mode (40% vs. 13%, P < 0.05), and less likely to complete all surveys (55% vs. 74%, P = 0.13). Patients using IVR were also less likely to complete all surveys (41% vs. 69%, P = 0.046).ConclusionsReported preferences for survey mode and completion rates differ by race, which may influence survey completion rates and highlight potential obstacles for equitable implementation of PROs into clinical care.  相似文献   
53.
Objective: Children with special health care needs are increasingly enrolling in managed care arrangements. However, existing managed care organizations, including traditional HMOs, are often poorly suited for caring for this population. In the adult health care area, new managed care entities, called Social HMOs (S/HMO) and Programs for the All-inclusive Care for the Elderly (PACE), have been created to integrate health and health-related services for chronically ill and disabled adults. We describe these models and assess their potential for serving children with special health care needs. Method: We reviewed the literature on managed care for children with special health care needs and evaluation findings from the S/HMO and PACE models for the elderly. Results: Evaluations of the S/HMO and PACE models have yielded mixed findings. Some of the more positive accomplishments include lower use and expenditures for long-term care services compared to other demonstration projects, greater integration of primary care physicians in decision making concerning long-term care, and improved management of transitions between care levels. On the negative side, start-up has been slow, prospective members have been hesitant to enroll, intermittent and sometimes frequent operating deficits have emerged, no discernible positive effects on health or social outcomes are apparent, and no significant overall savings have emerged. Conclusions: With mixed results so far, caution is required in applying these or similar models for vulnerable child populations. However, given the inadequacies of traditional managed care for this population, we believe experimentation with new models of care that integrate health and health-related services is important. Such experimentation should be fostered only to the extent that the models are carefully designed and then implemented in a manner that protects the interests of children with special health care needs.  相似文献   
54.
The current role of argon laser trabeculoplasty in the treatment of open angle glaucoma is still open discussion. To evaluate the effectiveness of ALT we performed a study on 36 patients followed for 2 years. We noted a success rate of 61.11% after 2 years and noticed that the success rate decreased in time. ALT should be considered as an intermediate therapy in the management of open angle glaucoma, after drug therapy has failed and before filtering surgery is performed.  相似文献   
55.
This study was designed to determine which objective acoustic or aerodynamic parameters allowed a homogeneous group of patients with unilateral vocal fold paralysis (UVFP) to be distinguished from an age-matched and smoking-matched control group and to search for linear correlations between the objective parameters and the subjective breathiness ratings. Eight patients with recent-onset UVFP and 12 controls were prospectively studied. The acoustic parameters measured for the vowel /a/ at a comfortable frequency and intensity were: jitter, shimmer, harmonics-to-noise ratio, cepstral peak prominence, the difference between the levels of the first two harmonics and the relative energy above 6 kHz. Aerodynamic parameters included the mean flow rate during a sustained /a/ and intraoral pressure during the production of the phoneme /pi/. The long-term average spectrum was calculated for 40 s of text, and the relative average energies in four frequency bands were compared. Six judges rated a mid-/a/ sample using a five-parameter scale with four levels of severity. Nonparametric statistical analysis revealed significant differences ( P<.05) between the UVFP group and the control group for 14 of the 19 parameters studied. Correlations between the objective parameters and perceived breathiness differed in the two groups. Correlations were not always as expected as based on previous literature reports. These measurements provided an objective qualification of voice in patients with UVFP and successfully distinguished them from the normal controls. The objective acoustic and aerodynamic measurements had generally low linear correlations with breathiness ratings in the control group. Higher correlations were seen in the UVFP group, in which breathiness was best correlated with airflow measurements.  相似文献   
56.
Use of radiolabeled antibodies in the treatment of childhood acute leukemia   总被引:1,自引:0,他引:1  
Abstract: Despite advances in therapy for acute leukemia, relapse continues to be the major cause of treatment failure. Hematopoietic stem cell transplant can rescue some patients after relapse, but the ability to escalate the intensity of preparative regimens is limited by toxicity to normal organs. Radiolabeled monoclonal antibodies against hematopoietic antigens have emerged as an alternative to deliver targeted supplemental radiation to sites of leukemic involvement while relatively sparing normal organs. This paper will review the rationale for using this approach, our current experience with radiolabeled anti-CD45 antibody, and the potential challenges encountered in treating children with radiolabeled antibodies.  相似文献   
57.
目的设计并合成与环佐辛有类似的阿片受体亲和活性、在体内具有较长作用时间的3-四氢呋喃甲基苯并吗吩烷类似物。方法8-三氟甲磺酸酯-3-四氢呋喃甲基苯并吗吩烷经催化氨化制得目标物,对目标物进行受体亲和力测定。结果8-氨基及8-苯氨基化合物在体外与μ,δ和κ受体的亲和力均较相应的8-羟基化合物低。结论目标化合物的体外受体亲和力相对较低,但此结果尚不能完全说明其在体内的作用情况及其可否用于毒品成瘾的治疗。进一步研究正在进行。  相似文献   
58.
PURPOSE: To assess the antitumor efficacy of pharmacokinetically guided topotecan dosing in previously untreated patients with medulloblastoma and supratentorial primitive neuroectodermal tumors, and to evaluate plasma and CSF disposition of topotecan in these patients. PATIENTS AND METHODS: After maximal surgical resection, 44 children with previously untreated high-risk medulloblastoma were enrolled, of which 36 were assessable for response. The topotecan window consisted of two cycles, administered initially as a 30-minute infusion daily for 5 days, lasting 6 weeks. Pharmacokinetic studies were conducted on day 1 to attain a topotecan lactone area under the plasma concentration-time curve (AUC) of 120 to 160 ng/mL.h. After 10 patients were enrolled, the infusion was modified to 4 hours, with dosage individualization. RESULTS: Of 36 assessable patients, four patients (11.1%) had a complete response and six (16.6%) showed a partial response, and disease was stable in 17 patients (47.2%). Toxicity was mostly hematologic, with only one patient experiencing treatment delay. The target plasma AUC was achieved in 24 of 32 studies (75%) in the 30-minute infusion group, and in 58 of 93 studies (62%) in the 4-hour infusion group. The desired CSF topotecan exposure was achieved in seven of eight pharmacokinetic studies when the topotecan plasma AUC was within target range. CONCLUSION: Topotecan is an effective agent against pediatric medulloblastoma in patients who have received no therapy other than surgery. Pharmacokinetically guided dosing achieved the target plasma AUC in the majority of patients. This drug warrants testing as part of standard postradiation chemotherapeutic regimens. Furthermore, these results emphasize the importance of translational research in drug development, which in this case identified an effective drug.  相似文献   
59.
BACKGROUND: We used a murine model of orthotopic corneal transplantation to determine whether host deficiency in ICAM-1 promotes survival of corneal grafts with different degrees of allodisparity. METHODS: ICAM-1-/- and wild-type C57BL/6 (ICAM-1+/+) received corneal grafts from the following strains of mice: BALB/c (fully mismatched), BALB.b (mismatched at multiple minor H only), or B10.D2 [including major histocompatibility complex (MHC) mismatch]. Graft rejection, induction of allospecific delayed-type hypersensitivity (DTH) responses, and leukocytic infiltration of grafts were measured. RESULTS: There were no differences in long-term survival of allografts that were either fully mismatched or had only minor H disparity in ICAM-1+/+ vs. ICAM-1-/-hosts. However, whereas B10.D2 grafts were accepted in only 58% of the ICAM-1+/+ hosts, graft survival in ICAM-1-/- recipients was 100% (P=0.006). Moreover, none of the ICAM-1-/- mice receiving B10.D2 grafts developed allospecific DTH. CONCLUSIONS: Prolonged survival seen in MHC-mismatched grafts in ICAM-1-/- mice, along with a suppressed DTH response to donor alloantigens after transplantation, suggest that ICAM-1 is associated with recipient sensitization to MHC alloantigens.  相似文献   
60.
Genomic sequences of the human polyomaviruses, JC virus (JCV) and BK virus (BKV), and simian virus 40 (SV40) have been reported from several types of human brain tumors, but there have been no population-based seroepidemiologic studies to evaluate the association between polyomavirus infection and brain tumors. We conducted a case-control study, nested within a prospective cohort, to investigate the association between antibodies to JCV, BKV, and SV40, as measured in serum collected 1-22 years before diagnosis and incident primary malignant brain tumors. Brain tumor cases (n = 44) and age-, gender-, and race-matched controls (n = 88) were identified from participants of two specimen banks in Washington County, Maryland. IgG antibodies to the capsid proteins of JCV and BKV were assessed using ELISAs. SV40-neutralizing antibodies were measured using plaque neutralization assays. Similar to the general population, the prevalence of JCV and BKV infection was high in our study population (77 and 85%, respectively). Antibodies to SV40 were less prevalent (11%). The odds ratio for subsequent brain tumor development was 1.46 [95% confidence interval (CI), 0.61-3.5] for JCV, 0.66 for BKV (95% CI, 0.22-1.95), and 1.00 for SV40 (95% CI, 0.30-3.32). Given the high prevalence of JCV and BKV infections and the millions who were potentially exposed to SV40 through contaminated polio vaccines, future studies should attempt to replicate these findings.  相似文献   
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