[Postoperative survival analysis of patients with stage Ⅲ-pN2 non-small cell lung cancer]

Objective: To investigate the effect of mediastinal lymph node resection, metastasis status and treatment on the prognosis of patients with stage Ⅲ-pN2 non-small cell lung cancer (NSCLC). Methods: Clinical data of 206 patients who were pathologically diagnosed as stage Ⅲ-pN2 NSCLC in Tongji Hospital from July 2006 to Dec 2009 were retrospectively analyzed and followed up. Log rank test and Cox proportional hazards regression model were used to analyze the prognostic significance of mediastinal lymph node excision, metastasis state and treatment. Results: The median overall survival (OS) time of the whole group was 29.6 months, and the median disease-free survival (DFS) time was 27.2 months. Univariate analysis showed that the less number of mediastinal lymph node stations with metastasis (single station), the less number of mediastinal lymph nodes involved (less than 2), and postoperative chemotherapy were associated with longer postoperative OS and DFS time (P<0.05 for all). The patients with skip metastasis, negative metastasis of subcarinal lymph node, the lower mediastinal lymph node metastasis rate (MLNR<33%) and postoperative radiotherapy had longer OS and DFS time than those without these factors (P<0.05 for all). Multivariate analysis showed that metastasis of subcarinal lymph node, MLNR and postoperative chemotherapy were the independent prognostic factors for patients with stage Ⅲ-pN2 NSCLC (P<0.05 for all). Conclusion: Metastasis of subcarinal lymph nodes and the higher MLNR might shorten the postoperative survival time of NSCLC patients with stage Ⅲ-pN2, whereas postoperative chemotherapy prolongs the survival time.

Greater trochanter of the femur (GTF) vs. proximal femoral nail anti-rotation (PFNA) for unstable intertrochanteric femoral fracture

OBJECTIVE

We aim to compare the effects of stem type prosthesis implantation of the greater trochanter of the femur (GTF) and proximal femur nail anti-rotation (PFNA) for treatment of unstable intertrochanteric femoral fracture.

PATIENTS AND METHODS

We retrospectively analyzed 108 patients with unstable intertrochanteric femoral fracture, including 61 cases who underwent GTF treatment and 47 cases who underwent PFNA treatment. We compared the operative time, blood loss, clinical healing and bone healing time, partial weight bearing and full weight bearing time, Harris hip score, rate of complications and rate of adverse reactions of implantation materials.

RESULTS

Comparing the two groups in terms of operative time and blood loss, the differences were not statistically significant (p>0.05). The clinical and bone healing time in the GTF group were shorter than those in the PFNA group and the differences were statistically significant (p<0.05). The partial and full-weight bearing times in the GTF group were significantly shorter than those in the PFNA group. The Harris scores, one and six months after surgery, were higher than those in the PFNA group and by comparing the scores after 12 and 18 months, the differences were not statistically significant (p>0.05). The rate of complications and rate of adverse reactions of implantation material in the GTF group were lower than those in the PFNA group and the differences were statistically significant (p<0.05).

CONCLUSIONS

GTF implantation is more advantageous in functional improvement and in reducing complications compared with PFNA for the treatment of unstable intertrochanteric femoral fracture.

Absolute CBV for the differentiation of recurrence and radionecrosis of brain metastases after gamma knife radiotherapy: a comparison with relative CBV

AIM

To investigate the efficiency of absolute cerebral blood volume (CBV) in the differentiation of tumour recurrence (TR) and radionecrosis (RN) in brain metastases (BM) and to evaluate the performance of absolute CBV compared to relative CBV (rCBV).

MATERIALS AND METHODS

Between March 2015 and June 2017, 46 patients with BM underwent quantitative dynamic susceptibility contrast perfusion-weighted imaging (DSC-PWI) because new enhancement had been demonstrated in irradiated lesions after gamma knife radiotherapy. The patients were assigned to either the TR group or RN group on the basis of MR perfusion follow-up or histopathological outcome. Absolute CBV of lesions (CBVlesion) and contralateral normal appearing white matter (CBVNAWM) in both groups were obtained. Mean rCBV were calculated as CBVlesion/CBVNAWM, which was equal to rCBV using traditional DSC-PWI.

RESULTS

CBVlesion of TR alone was significantly higher than the other parameters in both groups (p<0.001, separately). CBVlesion had smaller interobserver difference than CBVNAWM and rCBV (p<0.001, separately). Although CBVlesion significantly correlated with rCBV (r=0.914, p<0.001) and both had a similar specificity (96%) in differential diagnosis, CBVlesion had a higher sensitivity (96.9% versus 90.9%) to predict the treatment outcome. The best cut-off value of CBVlesion was 21.8 ml/100 g.

CONCLUSION

Quantitative DSC-PWI is a powerful method for the assessment of radiosurgically treated brain metastases. Absolute CBV has higher diagnostic efficiency than rCBV, which enables an absolute quantification of the regional CBV and prediction of tumour response. These advantages promote the intra- and inter-patient quantitative image comparison across different institutions.

The effect of nitridation on the polarity and optical properties of GaN self-assembled nanorods

We report on the effect of nitridation on GaN self-assembled nanorods grown on the c-plane sapphire by metalorganic chemical vapour deposition (MOCVD). Nitridation conditions are found to critically influence the nanorod morphology and optical properties. The nanorod polarity was determined through a direct observation of atomic dumbbell pairs. While purely N-polar wires are obtained under optimised nitridation, incomplete or missing nitridation leads to mixed polarity. By comparing the morphology and the crystal structure with spatially resolved cathodoluminescence results, our study unambiguously establishes a link between appropriate nitridation duration and a homogeneous improvement in optical quality.

Non-Dirac Chern insulators with large band gaps and spin-polarized edge states

Based on first-principles calculations and k·p models, we demonstrate that PbC/MnSe heterostructures are a non-Dirac type of Chern insulator with very large band gaps (244 meV) and exotically half-metallic edge states, providing the possibilities of realizing very robust, completely spin polarized, and dissipationless spintronic devices from the heterostructures. The achieved extraordinarily large nontrivial band gap can be ascribed to the contribution of the non-Dirac type electrons (composed of px and py) and the very strong atomic spin-orbit coupling (SOC) interaction of the heavy Pb element in the system. Surprisingly, the band structures are found to be sensitive to the different exchange and correlation functionals adopted in the first-principles calculations. Chern insulators with various mechanisms are acquired from them. These discoveries show that the predicted nontrivial topology in PbC/MnSe heterostructures is robust and can be observed in experiments at high temperatures. The system has great potential to have attractive applications in future spintronics.

Postcontrast T1 Mapping for Differential Diagnosis of Recurrence and Radionecrosis after Gamma Knife Radiosurgery for Brain Metastasis

BACKGROUND AND PURPOSE

The differential diagnosis of radionecrosis and tumor recurrence in brain metastases is challenging. We investigated the diagnostic efficiency of postcontrast T1 mapping in solving this problem.

MATERIALS AND METHODS

Between March 2016 and June 2017, fifty-six patients with brain metastases who underwent contrast-enhanced cerebral T1 mapping were recruited for this prospective study. The findings revealed new enhancement after gamma knife radiosurgery. The subjects were assigned to radionecrosis and recurrence groups based on follow-up (median, 11.5 months) and histopathologic results. T1 values of lesions 5 (T1_5min) and 60 (T1_60min) minutes after administration of contrast agent and their difference (T1_differ) were compared between the 2 groups with the 2-tailed Mann-Whitney U test. Receiver operating characteristic curves were used to determine the optimum cutoff values for differential diagnosis.

RESULTS

There were significant differences between the 2 groups in T1_5min, T1_60min, and T1_differ values (P = .012, P = .004, and P < .001, respectively). Relative to T1_5min and T1_60min, T1_differ exhibited greater sensitivity and specificity (P < .001, respectively) in identifying radionecrosis. The optimum T1_differ value for differential diagnosis was 71.1 ms (area under the curve = 0.97; 95% CI, 0.93-1.00), with sensitivity and specificity of 81.5% and 96.5%, respectively.

CONCLUSIONS

Postcontrast T1 mapping is optimal for the differential diagnosis of radionecrosis and tumor recurrence. Among T1 parameters, T1_differ is the most powerful parameter for differential diagnosis. Advantages in terms of quantitative analysis and high resolution portend the wide use of postcontrast T1 mapping in the future.

Pure red cell aplasia with t-cell large granular lymphocytic leukemia

Pure red cell aplasia (PRCA) develops as a result of erythroid precursors failing to reach maturity in the bone marrow, which eventually leads to anemia. Here we present a case of a 64-year-old Asian male with a medical history of colorectal adenocarcinoma who had been treated with 6 cycles of oxaliplatin and capecitabine four years ago. The patient was diagnosed with PRCA and T-cell large granular lymphocyte leukemia.

Depression and anxiety in multiple system atrophy

BACKGROUND

It has been noticed that the patients with multiple system atrophy (MSA) can accompany with depression and anxiety. This study aimed to establish the incidence and determinants of depression and anxiety symptoms in Chinese MSA patients.

METHODS

A total of 237 MSA patients were enrolled in the study. Neuropsychological assessment was performed using Hamilton Depression Rating Scale-24 items and Hamilton Anxiety Rating Scale.

RESULTS

We found that 62.0% and 71.7% patients had at least mild depression and anxiety symptoms, respectively. The severity of depression of MSA patients was associated with lower educational years (P=.024), longer disease duration (P<.001), and disease severity (P<.001). The severity of anxiety was associated with increased disease duration (P<.001), disease severity (P=.013), and orthostatic hypotension (P=.005). Binary logistic regression showed the determinants of depression and anxiety were female gender, longer disease duration, and disease severity.

CONCLUSION

Depression and anxiety symptoms are common in patients with MSA. Neurologists should pay attention to depression and anxiety in patients with MSA, especially in female patients and those with longer disease duration and severe disease condition.

Genome-wide DNA methylation profiling of articular cartilage reveals significant epigenetic alterations in Kashin-Beck disease and osteoarthritis

OBJECTIVE

To determine genome-wide DNA methylation profiles of knee cartilage from patients with Kashin-Beck disease (KBD) and osteoarthritis (OA).

METHOD

Knee cartilage was collected from 14 grade III KBD patients, 5 primary OA patients and 13 healthy subjects. The genome-wide methylation profiles of 5 KBD cartilage, 5 OA cartilage and 5 normal cartilage were determined by Illumina HumanMethylation450 array. Illumina Methylation Analyzer package was employed for identifying differentially methylated CpG sites. Functional annotation and enrichment analysis of differentially methylated genes (DMG) were conducted using GeneRIF database, Ingenuity Pathway Analysis (IPA) and The Database for Annotation, Visualization and Integrated Discovery (DAVID). Mass spectrometry (MS) and immunohistochemistry (IHC) were conducted to validate the functional relevance of identified KBD associated gene.

RESULTS

We identified a total of 1212 differentially methylated CpG sites in KBD vs Normal, annotated to 264 hypermethylated and 368 hypomethylated genes. Comparing the DNA methylation profiles of KBD vs Normal and OA vs Normal detected overlap of 367 differentially methylated CpG sites (annotated to 182 genes) as well as 845 KBD-specific differentially methylated CpG sites (annotated to 471 unique genes). MS and IHC confirmed the hypermethylation status and decreased protein expression of HAPLN1 gene in KBD cartilage.

CONCLUSION

Our data implicate epigenetic dysregulation of a host of genes in KBD and OA. Furthermore, we observed common causal epigenetic changes shared by KBD and OA.