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1.

Background

Available models for predicting lymph node invasion (LNI) in prostate cancer (PCa) patients undergoing radical prostatectomy (RP) might not be applicable to men diagnosed via magnetic resonance imaging (MRI)-targeted biopsies.

Objective

To assess the accuracy of available tools to predict LNI and to develop a novel model for men diagnosed via MRI-targeted biopsies.

Design, setting, and participants

A total of 497 patients diagnosed via MRI-targeted biopsies and treated with RP and extended pelvic lymph node dissection (ePLND) at five institutions were retrospectively identified.

Outcome measurements and statistical analyses

Three available models predicting LNI were evaluated using the area under the receiver operating characteristic curve (AUC), calibration plots, and decision curve analyses. A nomogram predicting LNI was developed and internally validated.

Results and limitations

Overall, 62 patients (12.5%) had LNI. The median number of nodes removed was 15. The AUC for the Briganti 2012, Briganti 2017, and MSKCC nomograms was 82%, 82%, and 81%, respectively, and their calibration characteristics were suboptimal. A model including PSA, clinical stage and maximum diameter of the index lesion on multiparametric MRI (mpMRI), grade group on targeted biopsy, and the presence of clinically significant PCa on concomitant systematic biopsy had an AUC of 86% and represented the basis for a coefficient-based nomogram. This tool exhibited a higher AUC and higher net benefit compared to available models developed using standard biopsies. Using a cutoff of 7%, 244 ePLNDs (57%) would be spared and a lower number of LNIs would be missed compared to available nomograms (1.6% vs 4.6% vs 4.5% vs 4.2% for the new nomogram vs Briganti 2012 vs Briganti 2017 vs MSKCC).

Conclusions

Available models predicting LNI are characterized by suboptimal accuracy and clinical net benefit for patients diagnosed via MRI-targeted biopsies. A novel nomogram including mpMRI and MRI-targeted biopsy data should be used to identify candidates for ePLND in this setting.

Patient summary

We developed the first nomogram to predict lymph node invasion (LNI) in prostate cancer patients diagnosed via magnetic resonance imaging-targeted biopsy undergoing radical prostatectomy. Adoption of this model to identify candidates for extended pelvic lymph node dissection could avoid up to 60% of these procedures at the cost of missing only 1.6% patients with LNI.  相似文献   
2.
Prediction of hemorrhagic transformation (HT) in patients treated by intravenous recombinant tissue-type plasminogen activator (rt-PA) is a challenging issue in acute stroke management. HT may be correlated with severe hypoperfusion. Signal changes may be observed at susceptibility-weighted magnetic resonance imaging (MRI) within large perfusion defects. A signal drop within cerebral veins at T2*-weighted gradient-echo MRI may be expected in severe ischemia, and may indicate subsequent risk of HT. The authors prospectively searched for an abnormal visibility of transcerebral veins (AVV) within the ischemic area in patients with hemispheric ischemic stroke, before they were treated with intravenous rt-PA therapy. Any correlation between AVV and baseline clinical or MRI findings, or further HT, was noted. An AVV was present in 23 of 49 patients (obvious, n = 8; moderate, n = 15), and was supported by severe hemodynamic changes at baseline MRI. The AVV was correlated with the occurrence of parenchymal hematoma type 2 at computed tomography during the first week (r = 0.44, P = 0.002). Five of six type 2 parenchymal hematomas occurred in association with obvious AVV. At multiple regression analysis, two baseline MRI factors had an independent predictive value for HT risk during the first week: the AVV and the cerebral blood volume ratio (Nagelkerke R2 = 0.48).  相似文献   
3.
multicenter study was conducted to evaluate a new temporary caval filter (TempofilterT) designed to be implanted for up to 6 weeks. A total of 66 patients with a mean age of 51.8 years were enrolled in the study. All had documented high risk of pulmonary embolism: severe deep venous thrombosis in 89.5% of cases and previous symptomatic pulmonary embolism in 65% of cases. Filter placement was performed in association with a surgical or obstetrical procedure in 68.5% of cases. The indication for filter placement was contraindication to or failure of anticoagulant therapy in 85% of the cases. The mean duration of implantation was 29.9 days. Pulmonary embolism was not observed during the implantation period. Partial thrombosis of the filter was observed in 15% of cases due to trapping of clots by the filter. Thrombosis did not hinder filter removal when attempted. Filter-related complications were minor. Filter migration occurred in only 7.5% of cases. Migration never led to complications and did not hinder filter removal. In all cases migration was due to specific, preventable causes. The results of this study show that the TempofilterT is not only safe and easy to use but also effective in preventing pulmonary embolism. A significantly longer maximum implantation time is a major advantage of the TempofilterT over conventional temporary filters. We believe that this filter can be used for temporary protection against the risk of pulmonary embolism particularly in young patients and in a surgical setting. (Ann Vasc Surg 1997;11:520–528.)  相似文献   
4.
Alazami syndrome (AS) (MIM# 615071) is an autosomal recessive microcephalic primordial dwarfism (PD) with recognizable facial features and severe intellectual disability due to depletion or loss of function variants in LARP7. To date, 15 patients with AS have been reported. Here we describe two consanguineous Algerian sisters with Alazami PD due to LARP7 homozygous pathogenic variants detected by whole exome sequencing. By comparing these two additional cases with those previously reported, we strengthen the key features of AS: severe growth restriction, severe intellectual disability and some distinguishing facial features such as broad nose, malar hypoplasia, wide mouth, full lips and abnormally set teeth. We also report significant new findings enabling further delineation of this syndrome: disproportionately mild microcephaly, stereotypic hand wringing and severe anxiety, thickened skin over the hands and feet, and skeletal, eye and heart malformations. From previous reviews, we summarize the main etiologies of PD according to the involved mechanisms and cellular pathways, highlighting their clinical core features.  相似文献   
5.
OBJECTIVE: To investigate the causal pathways by which age and the CCR5-Delta32, CCR2-64I, and SDF-1 3'A alleles influence progression to AIDS. DESIGN: Analysis of follow-up data from 2 cohort studies among homosexual men (n=400), having >10 years of follow-up. METHODS: The effects of the 4 cofactors on the CD4 and HIV-1 RNA trajectories after seroconversion were modeled in a random-effects model. A proportional hazards model was used to investigate their effect on the risk of AIDS after correction for CD4 cell count and RNA level. This approach allows investigation as to whether they influence AIDS progression by affecting CD4 count and RNA level or by other pathways. RESULTS: Persons of younger age or having the CCR2-64I or SDF-1 3'A mutation have significantly higher CD4 levels. Persons with the CCR5-Delta32 deletion or CCR2-64I mutation have significantly lower RNA levels. After correction for both CD4 count and RNA level, only the SDF-1 3'A mutation significantly increases the AIDS risk. CONCLUSIONS: Age and the CCR5-Delta32 deletion and CCR2-64I mutation influence AIDS progression by affecting CD4 and HIV-1 RNA. The SDF-1 3'A allele increases the AIDS risk, but this effect is countered by its effect on CD4 and HIV-1 RNA level.  相似文献   
6.
NS3 protease is essential for hepatitis C Virus (HCV) replication, and is one of the most promising targets for specific anti-HCV therapy. Its natural polymorphism has not been studied at the quasispecies level. In the present work, the genetic heterogeneity of the NS3 protease gene was analyzed in 17 HCV genotype 1 (5 subtypes 1a and 12 subtypes 1b) samples collected from infected patients before anti-viral therapy. A total of 294 clones were sequenced. Although the protease NS3 is considered to be one of the less variable genes in the HCV genome, variability of both nucleotide and amino acid sequences was found. In variants belonging to 1a and 1b subtypes, 224 and 267 of 543 positions showed one or more nucleotide substitutions, respectively. Forty and 74 of the 181 NS3 amino acid positions showed at least one mutation in HCV-1a and HCV-1b isolates, respectively. Most substitutions were conservative. This substantial polymorphism of the NS3 protease produced by HCV-1a and HCV-1b suggests that, despite the numerous functional and structural constraints, the enzyme is sufficiently flexible to tolerate substitutions.  相似文献   
7.
Introduction: Ghrelin is an orexigenic hormone which favors food-seeking behavior and has been postulated to be a biomarker of stress. We conducted a systematic review and meta-analysis on the evolution of ghrelin levels following acute stress. Methods: The PubMed, Cochrane Library, Embase, and ScienceDirect databases were searched for studies reporting ghrelin levels before and after acute stress in humans. Results: We included ten studies for a total of 348 patients. Acute stress (intervention) was always in a laboratory. Acute stress was psychological (Trier Social Stress Test), physical, or mixed (cold pressure test). The overall meta-analysis demonstrated an increase in ghrelin after the stress intervention (ES = 0.21, 95CI 0.09 to 0.34) compared with baseline levels. Stratification by time demonstrated an acute increase in ghrelin levels in the five minutes immediately following the initiation of stress (0.29, 0.10 to 0.48) but without any difference after. Obese individuals had a more significant (ES = 0.51, 95CI 0.18 to 0.84) and prolonged increase in ghrelin levels for up to 45 min compared with non-obese individuals who had a significant increase only five minutes after stress. Moreover, the ghrelin levels increased in response to stress with BMI (coefficient 0.028, 0.01 to 0.49; p = 0.013) and decreased with the time after the stress intervention (coefficient -0.007, −0.014 to −0.001; p = 0.025). Conclusion: Ghrelin is a biomarker of stress, with a short-term increase following acute stress. Obese individuals have both a higher and prolonged response, emphasizing the link between obesity and stress.  相似文献   
8.
In 1996 Congress enacted legislation which, among other things, substantially cut off Supplemental Security Income payments and food stamps for present and future legal alien residents of the United States, and made it much harder for them to qualify for Medicaid. For low-income elderly immigrants, who constituted more than two-thirds of aliens on SSI, the adverse and potential impacts were substantial in terms of economic hardship and access to health care. In the months that followed, their plight received significant attention from the media and state and local politicians who now had greater economic and social responsibilities thrust upon them. One year later, Congress restored SSI benefits only for aliens who been receiving them before August 22, 1996 and made it easier for them to qualify for Medicaid. Food stamp benefits, however, were not restored. The limited scope of this restoration of benefits means that many of today's older immigrants, as well as those in the future, will be faced with serious problems in meeting their basic income and health care needs.  相似文献   
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