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1.

Background

Programmed death ligand-1 (PD-L1) is a potential predictive biomarker for immunotherapy in several malignancies. However, the expression level and clinical significance of PD-L1 in von Hippel–Lindau (VHL)-associated hereditary clear-cell renal cell carcinoma (ccRCC) remain unclear.

Patients and Methods

Surgical specimens were recruited from 129 patients with sporadic ccRCC and 26 patients with VHL-associated hereditary ccRCC. The PD-L1 expression level was assessed using immunohistochemistry. Correlations between PD-L1 expression and clinicopathological features were analyzed.

Results

In sporadic ccRCC, the positive expression rate of PD-L1 was 47.3% (61/129). Positive PD-L1 expression was correlated with advanced tumor T stage (P = .011), higher Fuhrman nuclear grade (P = .022), poor disease-free survival (P = .037), and sex (P = .025). In the VHL-associated hereditary ccRCC, positive PD-L1 expression rate was 34.6% (9/26), lower than that in sporadic ccRCC. Positive PD-L1 was correlated with higher Fuhrman nuclear grade (P = .008), but not with sex, age, tumor stage, or the onset age of VHL-associated tumors.

Conclusion

Positive PD-L1 expression was correlated with the aggressive clinicopathological features in sporadic and VHL-associated hereditary ccRCC. Whether PD-L1 expression level in ccRCC is related to the effectiveness of programmed death-1/PD-L1 checkpoint inhibitor immunotherapy needs to be further investigated.  相似文献   
2.
Objective To analyze the variants of 42 Chinese patients with Bartter syndrome type 3 (BS3) and explore the characteristics of genotype and phenotype. Methods Forty-two genetically diagnosed patients from 40 Han and one Hui families were collected in the Affiliated Hospital of Qingdao University and the Affiliated Qingdao Municipal Hospital of Qingdao University during the period of June 2012 to October 2018. The second-generation sequencing and multiplex ligase probe-dependent amplification (MLPA) technique were used to analyze the CLCNKB gene variation and its characteristics in children with BS3. The clinical data were collected, and the therapeutic effect and growth improvement were observed and followed up. Thirty eight patients were divided into severe (n=26) and light (n=12) groups according to the severity of genetic variation. The clinical phenotypic characteristics of the two groups were compared. Results Thirty-six variants including 16 novel ones of CLCNKB gene were found. The whole gene deletion of CLCNKB gene was the most frequent mutation (40%), and the rate of large deletions was up to 55%. The most common symptoms included development retardation (38/42), polydipsia and polyuria (35/42), constipation (31/42) and vomiting (27/42). All patients presented with hypokalemia, hypochloremia and metabolic alkalosis. After the medicine treatment that based on indomethacin and potassium chloride, most patients could achieve obvious recovery of growth rate and restoration of hypokalemia. The severe group showed more severe metabolic alkalosis than the light group. Conclusions Thirty-six variants of CLCNKB gene have been found in this study, including 16 novel ones, which enrich the human gene mutation database (HGMD) and provide valuable references to diagnosis, treatment and the genetic counseling of Chinese population.  相似文献   
3.
Twins with Duchenne muscular dystrophy (DMD) have been widely studied. We report the first rare case of monozygotic triplets with DMD who shared consistent phenotypes, including delayed motor and language milestones, muscle wasting and weakness, joint contracture, and lumbar lordosis. Muscle magnetic resonance imaging and biopsy revealed the similar muscle injury characteristics and dystrophin absence. Short tandem repeat analysis confirmed monozygosity. A de novo mutation (exon 49–52 deletion) was found in the triplets but not in their mother. Treatment included prednisone, idebenone, and rehabilitation management. At the 2-year follow-up, motor function had deteriorated, and muscle fatty infiltration was more extensive and severe. Our case offers a unique opportunity for genetic and therapeutic research. Furthermore, it highlights the critical role of genetic factors in DMD phenotypes and provides a potential choice for treatment observations.  相似文献   
4.

Objective

To assess the impact of focality and location of positive surgical margins (PSM) on long-term outcomes after radical prostatectomy (RP) for prostate cancer (PCa), including biochemical recurrence (BCR), metastasis and overall mortality.

Patients and Methods

From a total of 2796 cases of RP between 1993 and 2007 in our single hospital, 476 cases with PSMs were identified and included in this study. PSM location was categorized into apex, peripheral, and bladder neck. Survival was estimated using the Kaplan-Meier method. Cox proportional hazard regression models were used to analyze the impact of PSM focality and location status on oncologic survival.

Results

Of these 476 cases with PSMs, 335 (70.4%) cases were with single focal (sF) PSMs and 141 (29.6%) cases were with multifocal (mF) PSMs. Furthermore, 406 (85.3%) cases were found to have single location (sL) PSMs, and 70 (14.7%) cases were with multilocation (mL) PSMs. The median follow-up was 12.9 years. mF-PSMs and mL-PSMs showed significant impact on increased BCR risk on univariate analysis, and mL-PSMs remained significant on multivariate analysis (P = .048). Furthermore, the combination of multifocality and multilocation showed added prognostic value on predicting BCR-free survival, but not on metastasis-free survival or overall survival.

Conclusion

The presence of mF-PSMs and mL-PSMs, and especially the combination of both, demonstrated significant impact on BCR prognosis. Patients with apex sLsF-PSMs were less likely to have BCR when compared with all those with non-apex sLsF-PSMs. These results should be considered when evaluating patients for adjuvant therapy.  相似文献   
5.
6.
Abstract

Background: Increasing access to buprenorphine treatment is a critical tool for addressing the opioid epidemic in the United States. In 2016, a federal policy change allowed physicians who meet specific requirements to treat up to 275 concurrent buprenorphine patients. This study examines state-level measures of buprenorphine treatment supply over 21?months since this policy change and estimates associations between the supply of 275-patient waivers and state characteristics. Methods: Monthly state-level measures of the number of physicians holding the 275-patient waiver per 100,000 residents were constructed from September 2016 to May 2018 using the Drug Enforcement Agency’s Controlled Substance Act database. State characteristics were obtained from publicly available sources. Mixed-effects regression models were estimated to examine change over time. Results: During the 21-month period, the number of physicians waivered to treat 275 patients increased from 153 to 4009 physicians. The mean supply of 275-patient physicians per 100,000 state residents significantly increased from 0.07 (SD?=?0.21) in September 2016 to 1.43 (SD?=?1.08) in May 2018 (t?=??9.84, df?=?50, P?<?.001). The final mixed-effects regression model indicated that Census division and the preexisting supply of 100-patient waivered physicians were correlated with the rate of growth in 275-patient waivers over the study period. Conclusions: Although uptake of the 275-patient waiver has exceeded initial projections, growth is uneven across the United States. Unequal patterns of growth pose a challenge to efforts to increase treatment availability as a means of addressing the opioid epidemic.  相似文献   
7.
目的探讨康复运动操联合牵引在老年腰椎间盘突出症患者中的应用效果及对腰椎活动度的影响。 方法选择2018年10月至2019年9月老年腰椎间盘突出症患者86例作为对象,随机分为对照组(n=43例)和观察组(n=43例)。对照组采用常规牵引治疗,观察组在对照组基础上联合康复运动操治疗,4周治疗后对患者效果进行评估,比较两组视觉模拟疼痛(VAS)评分、炎症因子水平、腰椎活动度及满意度。 结果观察组治疗后1、2、3、4周VAS评分低于对照组(P<0.05);观察组治疗后4周IL-1β、TNF-α及TXB2水平均低于对照组(P<0.05);观察组治疗后4周前屈、后伸、侧屈均高于对照组(P<0.05);观察组治疗后4周遵医治疗、康复运动、定期复查、治疗效果及治疗形式满意度均高于对照组(P<0.05)。 结论康复运动操联合牵引能减轻老年腰椎间盘突出症患者疼痛,提高患者腰椎活动度,且两种方法干预能降低机体炎症瀑布联级反应,提高患者治疗满意度,值得推广应用。  相似文献   
8.
ABSTRACT

Various machine learning techniques have been developed for keratoconus detection and refractive surgery screening. These techniques utilize inputs from a range of corneal imaging devices and are built with automated decision trees, support vector machines, and various types of neural networks. In general, these techniques demonstrate very good differentiation of normal and keratoconic eyes, as well as good differentiation of normal and form fruste keratoconus. However, it is difficult to directly compare these studies, as keratoconus represents a wide spectrum of disease. More importantly, no public dataset exists for research purposes. Despite these challenges, machine learning in keratoconus detection and refractive surgery screening is a burgeoning field of study, with significant potential for continued advancement as imaging devices and techniques become more sophisticated.  相似文献   
9.

Background

Pure mucinous breast cancer (PMBC) is a rare pathologic type of breast cancer, the prognostic factors of which have not been clearly defined. This study aimed to analyze the prognostic markers and distribution of 21-gene recurrence score (RS) in patients with PMBC.

Patients and Methods

Utilizing the Surveillance, Epidemiology, and End Results (SEER) database, a retrospective analysis of PMBC cases was conducted. Multivariate analyses were used to evaluate the indicators for prognosis and the correlations between RS and traditional clinicopathologic characteristics. Disease was subdivided into 4 molecular phenotypes using estrogen receptor (ER) status and tumor grade.

Results

Of the 8048 patients, most had ER-positive and node-negative tumors. Multivariate analysis revealed that molecular phenotype as well as age, race, tumor size, and lymph node status was an independent prognostic factor for patients with PMBC (P < .05). The 5-year breast cancer–specific survival of patients among different phenotypes was significantly different (97.9% for ER-positive and grade I tumor, 96.9% for ER-positive and grade II-III tumor, 96% for ER-negative and grade I tumor, 90.1% for ER-negative and grade II-III tumors, P < .001). The proportions of patients categorized into low, intermediate, and high RS risk group were 64.9%, 31.9%, and 3.2%, respectively. Grade, progesterone receptor status, and age were identified as independent variables associated with RS.

Conclusion

PMBC had favorable biological features and relatively good prognosis. Molecular phenotype as well as age, race, tumor size, and lymph node status were independent prognostic markers. Furthermore, age, progesterone receptor status, and grade could independently predict RS.  相似文献   
10.
Lin  Hua  Li  Muwei  Zhan  Yang  Lin  Li  Yang  Kun  Hu  Shimin  Han  Ying 《Brain imaging and behavior》2021,15(4):1739-1747

The ε4 allele of the APOE gene is thought to increase risk from amnestic mild cognitive impairment (aMCI) to Alzheimer’s disease. Cognitive decline in the condition is increasingly considered to worsen functional disconnections in brain network composed of gray matter and white matter. Nevertheless, Whether APOEε4 targets specific white matter functional connectivity in patients with aMCI remains mostly unexplored, mainly due to the challenges of detecting BOLD signals in white matter. Here, we applied a novel approach to investigate APOEε4-related specific bundles and cortical area alterations in aMCI subjects, in order to characterize white matter-gray matter functional connectivity differences throughout the brain. We analyzed 75 patients with aMCI and 76 demographically matched normal controls. The aMCI APOEε4 carriers showed decreased functional connectivity located at left corticospinal tract, bilateral posterior limb of internal capsule, and right temporopolaris, which was different from the regions of aMCI-related changes. We further found that recognition scores were positively associated with the right temporopolaris in aMCI APOEε4 carriers. Collectively, the data provide new evidence that APOEε4 genotype exerts a negative impact on neural activity in both gray and white matter in aMCI, which potentially contributes to functional disconnection and memory decline. A novel method provides full-scale measuring effect of disease conditions on functional architecture throughout the brain. Trial registration: https://www.ClinicalTrials.gov (Identifier: NCT02225964). Registered January 2014.

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