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91.
92.
HCM, the most common inherited cardiac disease, is mainly caused by mutations in sarcomeric genes. More than a third of the patients are heterozygous for mutations in the MYH7 gene encoding for the β-myosin heavy chain. In HCM-patients, expression of the mutant and the wildtype allele can be unequal, thus leading to fractions of mutant and wildtype mRNA and protein which deviate from 1:1. This so-called allelic imbalance was detected in whole tissue samples but also in individual cells. There is evidence that the severity of HCM not only depends on the functional effect of the mutation itself, but also on the fraction of mutant protein in the myocardial tissue. Allelic imbalance has been shown to occur in a broad range of genes. Therefore, we aimed to examine whether the MYH7-alleles are intrinsically expressed imbalanced or whether the allelic imbalance is solely associated with the disease. We compared the expression of MYH7-alleles in non-HCM donors and in HCM-patients with different MYH7-missense mutations. In the HCM-patients, we identified imbalanced as well as equal expression of both alleles. Also at the protein level, allelic imbalance was determined. Most interestingly, we also discovered allelic imbalance and balance in non-HCM donors. Our findings therefore strongly indicate that apart from mutation-specific mechanisms, also non-HCM associated allelic-mRNA expression regulation may account for the allelic imbalance of the MYH7 gene in HCM-patients. Since the relative amount of mutant mRNA and protein or the extent of allelic imbalance has been associated with the severity of HCM, individual analysis of the MYH7-allelic expression may provide valuable information for the prognosis of each patient.  相似文献   
93.
94.

Purpose

To describe the natural history and identify predictors of cancer-specific survival in patients who experience disease recurrence after radical nephroureterectomy (RNU) for upper tract urothelial carcinoma (UTUC).

Methods

Of 2,494 UTUC patients treated with RNU without neoadjuvant chemotherapy, 597 patients experienced disease recurrence. A total of 148 patients (25?%) received adjuvant chemotherapy before disease recurrence. Multivariable Cox regression model addressed time to cancer-specific mortality after disease recurrence.

Results

The median time from RNU to disease recurrence was 12?months (interquartile range 5?C22). A total of 491 (82?%) of 597 patients died from UTUC, and 8 patients (1.3?%) died from other causes. The median time from disease recurrence to death of UTUC was 10?months. Actuarial cancer-specific survival estimate at 12?months after disease recurrence was 35?%. On multivariable analysis that adjusted for the effects of standard clinicopathologic characteristics, higher tumor stages [hazard ratio (HR) pT3 vs. pT0?CT1: 1.66, p?=?0.001; HR pT4 vs. pT0?CT1: 1.90, p?=?0.002], absence of lymph node dissection (HR 1.28, p?=?0.041), ureteral tumor location (HR 1.44, p?<?0.0005) and a shorter interval from surgery to disease recurrence (p?<?0.0005) were significantly associated with cancer-specific mortality. The adjusted 6-, 12- and 24-month postrecurrence cancer-specific mortality was 73, 60 and 57?%, respectively.

Conclusions

Approximately 80?% of patients who experience disease recurrence after RNU die within 2?years after recurrence. Patients with non-organ-confined stage, absence of lymph node dissection, ureteral tumor location and/or shorter time to disease recurrence died of their tumor more quickly than their counterparts. These factors should be considered in patient counseling and risk stratification for salvage treatment decision making.  相似文献   
95.
Study Type – Decision analysis (based on alternative scenarios) Level of Evidence 2b What's known on the subject? and What does the study add? Several studies have shown that abnormal levels of nuclear matrix protein 22 (NMP22) are associated with bladder cancer, and NMP22 has been approved by the FDA as a urinary biomarker for bladder cancer detection and surveillance. However, the benefit of adding NMP22 to the clinical care of patients remains unclear. Decision curve analysis incorporates the consequences of clinical decisions, such as an increased number of unnecessary cystoscopies or missed cancers.

OBJECTIVE

  • ? To employ decision curve analysis to determine the impact of nuclear matrix protein 22 (NMP22) on clinical decision making in the detection of bladder cancer using data from a prospective trial.

PATIENTS AND METHODS

  • ? The study included 1303 patients at risk for bladder cancer who underwent cystoscopy, urine cytology and measurement of urinary NMP22 levels.
  • ? We constructed several prediction models to estimate risk of bladder cancer. The base model was generated using patient characteristics (age, gender, race, smoking and haematuria); cytology and NMP22 were added to the base model to determine effects on predictive accuracy.
  • ? Clinical net benefit was calculated by summing the benefits and subtracting the harms and weighting these by the threshold probability at which a patient or clinician would opt for cystoscopy.

RESULTS

  • ? In all, 72 patients were found to have bladder cancer (5.5%). In univariate analyses, NMP22 was the strongest predictor of bladder cancer presence (predictive accuracy 71.3%), followed by age (67.5%) and cytology (64.3%).
  • ? In multivariable prediction models, NMP22 improved the predictive accuracy of the base model by 8.2% (area under the curve 70.2–78.4%) and of the base model plus cytology by 4.2% (area under the curve 75.9–80.1%).
  • ? Decision curve analysis revealed that adding NMP22 to other models increased clinical benefit, particularly at higher threshold probabilities.

CONCLUSIONS

  • ? NMP22 is a strong, independent predictor of bladder cancer.
  • ? Addition of NMP22 improves the accuracy of standard predictors by a statistically and clinically significant margin.
  • ? Decision curve analysis suggests that integration of NMP22 into clinical decision making helps avoid unnecessary cystoscopies, with minimal increased risk of missing a cancer.
  相似文献   
96.
Urothelial carcinoma of the urinary bladder (UCB) is a highly heterogeneous malignancy that causes significant morbidity and mortality. Despite advances in surgical and medical treatment, there has been no change in mortality in UCB over the past decades. Standard pathological features (stage, grade, nodal status) provide only limited information regarding biological potential and clinical behavior. Molecular biomarkers may shed light on important mechanisms of pathogenesis, provide useful additional prognostic information, and serve as targets for therapy. This review summarizes recent advances and the most promising UCB tissue and blood biomarkers of the past few years. We discuss the predictive and prognostic value of biomarkers at different stages of UCB. There is no doubt that a panel of biomarkers will eventually improve our clinical decision-making with regard to treatment and follow-up.  相似文献   
97.
Dendritic cells are able to present viral antigens to T-cells after uptake of apoptotic bodies derived from virus-infected cells. Immunization with virus-infected apoptotic cells was previously shown to induce HIV-specific immune responses in mice. Here we evaluate the safety and immunogenicity of immunization with activated apoptotic cells in non-human primates using autologous T-cells infected with replication defective VSV pseudotyped SIV(mac239)Δenv. Animals were immunized with γ-irradiated activated T-cells carrying the VSVenvSIV(mac239)Δenv pseudovirus. SIV Gag-specific cellular immune responses were induced as early as two weeks after the first immunization eliciting a biased IFN-γ and IL-2 response. In addition, induction of SIV Gag-specific antibody responses and high titer neutralizing activity against the SIV pseudovirus harboring a VSV-env were detected after two immunizations. The vaccinated group and a control group of Chinese rhesus macaques were intravenously challenged with pathogenic SIV(mac251.) All animals became infected, but SIV-replication was effectively suppressed (below 100 copies/ml) in several animals in both groups. However the group immunized with apoptotic cells revealed better preservation of the gut CD4(+) T-cell compartment. Viral control was inversely correlated with an early (4 weeks) but transient increase in the percentage of Ki67(+)CD4(+) peripheral blood T-cells (Spearman -0.73). We here show that immunizations with activated apoptotic lymphocytes expressing transduced SIV genes result in induction of both cellular and humoral immune responses. This study provides evidence for an immunological principle demonstrating that certain apoptotic cells can be considered as carriers of antigens directing immune responses in macaques.  相似文献   
98.
Krishnan V  Collop NA  Scherr SC 《Chest》2008,133(5):1135-1141
BACKGROUND: Oral appliances (OAs) are first-line therapy for mild-to-moderate obstructive sleep apnea (OSA) and are being used with increasing frequency. Additionally, best practice of OA titration is unknown. We describe the experience of patients treated with an OA, identify factors that predict treatment success with an OA, and offer a protocol for OA titration. METHODS: We retrospectively studied patients seen in a dental sleep clinic between 2002 and 2006. Patients selected for OA treatment underwent baseline polysomnography, were individually fit with an OA, and were instructed to titrate it at home until symptom resolution or discomfort. During follow-up polysomnography, additional titration was performed as needed. Primary outcome was successful treatment, defined as apnea-hypopnea index (AHI) <10 events per hour and AHI decrease at least 50% from baseline. Logistic regression models were created to identify associations between patient characteristics and successful treatment. Overall differences in AHI at baseline, after home titration, and after final titration were compared using Kruskal-Wallis test, and post hoc comparisons were performed with sign tests, with Bonferroni corrections. RESULTS: Of 57 subjects treated with an OA, 37 subjects (64.9%) were successfully treated with OA therapy. Of the 49 subjects for whom data were available for AHI after home titration, 27 subjects (55%) achieved successful treatment of OSA by self-titration, without need for further titration during follow-up polysomnography. CONCLUSIONS: A majority of subjects, regardless of OSA severity, are successfully treated with an OA. Men and younger patients were found to be the best responders. The titration protocol for an OA offers a beneficial initial step in the treatment of OSA.  相似文献   
99.
Late conduction defects following aortic valve replacement   总被引:1,自引:0,他引:1  
BACKGROUND AND AIM OF THE STUDY: The study aim was to determine the incidence and clinical significance of late cardiac conduction defects (CD) after aortic valve replacement (AVR). METHODS: An analysis was made of 100 consecutive cases after AVR in a prospective outpatient evaluation program. RESULTS: The perioperative (30-day) mortality rate was 5%, and incidence of perioperative pacemaker implantation 3%. Among patients, 19% had CDs before surgery; a normal ECG was present during all periods in 45% of patients. The most frequent perioperative CD was left anterior hemiblock (LAHB; n = 8), and the most frequent late CD was left bundle branch block (LBBB; n = 8). Overall, 13.7% of operative survivors with normal preoperative and perioperative ECGs developed late CDs; one patient (1%) required pacemaker implantation 82 months after AVR. A further three patients (3%) had worsening of pre-existent CDs. Late CDs occurred over a wide time range (3 to 102 months) after surgery. CONCLUSION: There is an important incidence of CDs that occur late after AVR, even if the perioperative ECGs are normal; however, a need for late pacemaker implantation is rare. As CDs may occur at any time after surgery, regular follow up with precise evaluation of ECGs is called for.  相似文献   
100.
Endorectal ultrasound: instrumentation and clinical aspects   总被引:20,自引:2,他引:20  
During the period 1983 to April 1986, 129 patients with rectal cancer were treated. In 76 of these depth of penetration of the rectal wall by tumour was assessed by ultrasound. T stage determined by ultrasound (uT) corresponded with the pathological stages (pT) in 67 patients. In the remaining 9 cases, ultrasound overstaged the tumour and in only one patient was the growth understaged. Lymph nodes could be visualised in 12 out of 27 patients in whom nodes were looked for but only six cases were found to be positive on histological examination. Of 22 recurrences detected or proven by ultrasound there was a group of 6 patients who had no other sign of recurrence.  相似文献   
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