Machine Learning Radiomics-Based Prediction of Non-sentinel Lymph Node Metastasis in Chinese Breast Cancer Patients with 1-2 Positive Sentinel Lymph Nodes: A Multicenter Study.

RATIONALE AND OBJECTIVES: This study aimed to construct a machine learning radiomics-based model using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) images to evaluate non-sentinel lymph node (NSLN) metastasis in Chinese breast cancer (BC) patients who underwent total mastectomy (TM) and had 1-2 positive sentinel lymph nodes (SLNs). MATERIALS AND METHODS: In total, 494 patients were retrospectively enrolled from two hospitals, and were divided into the training (n = 286), internal validation (n = 122), and external validation (n = 86) cohorts. Features were extracted from DCE-MRI images for each patient and screened. Six ML classifies were trained and the best classifier was evaluated to calculate radiomics (Rad)-scores. A combined model was developed based on Rad-scores and clinical risk factors, then the calibration, discrimination, reclassification, and clinical usefulness were evaluated. RESULTS: 14 radiomics features were ultimately selected. The random forest (RF) classifier showed the best performance, with the highest average area under the curve (AUC) of 0.833 in the validation cohorts. The combined model incorporating RF-based Rad-scores, tumor size, lymphovascular invasion, and proportion of positive SLNs resulted in the best discrimination ability, with AUCs of 0.903, 0.890, and 0.836 in the training, internal validation, and external validation cohorts, respectively. Furthermore, the combined model significantly improved the classification accuracy and clinical benefit for NSLN metastasis prediction. CONCLUSION: A RF-based combined model using DCE-MRI images exhibited a promising performance for predicting NSLN metastasis in Chinese BC patients who underwent TM and had 1-2 positive SLNs, thereby aiding in individualized clinical treatment decisions.

Development and validation of convolutional neural network-based model to predict the risk of sentinel or non-sentinel lymph node metastasis in patients with breast cancer: a machine learning study.

Background: For patients with sentinel lymph node (SLN) metastasis and low risk of residual non-SLN (NSLN) metastasis, axillary lymph node (ALN) dissection could lead to overtreatment. This study aimed to develop and validate an automated preoperative deep learning-based tool to predict the risk of SLN and NSLN metastasis in patients with breast cancer (BC) using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) images. Methods: In this machine learning study, we retrospectively enrolled 988 women with BC from three hospitals in Zhejiang, China between June 1, 2013 to December 31, 2021, June 1, 2017 to December 31, 2021, and January 1, 2019 to June 30, 2023, respectively. Patients were divided into the training set (n = 519), internal validation set (n = 129), external test set 1 (n = 296), and external test set 2 (n = 44). A convolutional neural network (CNN) model was proposed to predict the SLN and NSLN metastasis and was compared with clinical and radiomics approaches. The performance of different models to detect ALN metastasis was measured by the area under the curve (AUC), accuracy, sensitivity, and specificity. This study is registered at ChiCTR, ChiCTR2300070740. Findings: For SLN prediction, the top-performing model (i.e., the CNN algorithm) achieved encouraging predictive performance in the internal validation set (AUC 0.899, 95% CI, 0.887-0.911), external test set 1 (AUC 0.885, 95% CI, 0.867-0.903), and external test set 2 (AUC 0.768, 95% CI, 0.738-0.798). For NSLN prediction, the CNN-based model also exhibited satisfactory performance in the internal validation set (AUC 0.800, 95% CI, 0.783-0.817), external test set 1 (AUC 0.763, 95% CI, 0.732-0.794), and external test set 2 (AUC 0.728, 95% CI, 0.719-0.738). Based on the subgroup analysis, the CNN model performed well in tumour group smaller than 2.0 cm, with the AUC of 0.801 (internal validation set) and 0.823 (external test set 1). Of 469 patients with BC, the false positive rate of SLN prediction declined from 77.9% to 32.9% using CNN model. Interpretation: The CNN model can predict the SLN status of any detectable lesion size and condition of NSLN in patients with BC. Overall, the CNN model, employing ready DCE-MRI images could serve as a potential technique to assist surgeons in the personalized axillary treatment of in patients with BC non-invasively. Funding: National Key Research and Development projects intergovernmental cooperation in science and technology of China, National Natural Science Foundation of China, Natural Science Foundation of Zhejiang Province, and Zhejiang Medical and Health Science Project.

Multi-algorithms analysis for pre-treatment prediction of response to transarterial chemoembolization in hepatocellular carcinoma on multiphase MRI.

OBJECTIVES: This study compared the accuracy of predicting transarterial chemoembolization (TACE) outcomes for hepatocellular carcinoma (HCC) patients in the four different classifiers, and comprehensive models were constructed to improve predictive performance. METHODS: The subjects recruited for this study were HCC patients who had received TACE treatment from April 2016 to June 2021. All participants underwent enhanced MRI scans before and after intervention, and pertinent clinical information was collected. Registry data for the 144 patients were randomly assigned to training and test datasets. The robustness of the trained models was verified by another independent external validation set of 28 HCC patients. The following classifiers were employed in the radiomics experiment: machine learning classifiers k-nearest neighbor (KNN), support vector machine (SVM), the least absolute shrinkage and selection operator (Lasso), and deep learning classifier deep neural network (DNN). RESULTS: DNN and Lasso models were comparable in the training set, while DNN performed better in the test set and the external validation set. The CD model (Clinical & DNN merged model) achieved an AUC of 0.974 (95% CI: 0.951-0.998) in the training set, superior to other models whose AUCs varied from 0.637 to 0.943 (p < 0.05). The CD model generalized well on the test set (AUC = 0.831) and external validation set (AUC = 0.735). CONCLUSIONS: DNN model performs better than other classifiers in predicting TACE response. Integrating with clinically significant factors, the CD model may be valuable in pre-treatment counseling of HCC patients who may benefit the most from TACE intervention.

CYLD deubiquitinates plakoglobin to promote Cx43 membrane targeting and gap junction assembly in the heart.

During heart maturation, gap junctions assemble into hemichannels and polarize to the intercalated disc at cell borders to mediate electrical impulse conduction. However, the molecular mechanism underpinning cardiac gap junction assembly remains elusive. Herein, we demonstrate an important role for the deubiquitinating enzyme cylindromatosis (CYLD) in this process. Depletion of CYLD in mice impairs the formation of cardiac gap junctions, accelerates cardiac fibrosis, and increases heart failure. Mechanistically, CYLD interacts with plakoglobin and removes lysine 63-linked polyubiquitin chains from plakoglobin. The deubiquitination of plakoglobin enhances its interaction with the desmoplakin/end-binding protein 1 complex localized at the microtubule plus end, thereby promoting microtubule-dependent transport of connexin 43 (Cx43), a key component of gap junctions, to the cell membrane. These findings establish CYLD as a critical player in regulating gap junction assembly and have important implications in heart development and diseases.

Home Dust Mites Promote MUC5AC Hyper-Expression by Modulating the sNASP/TRAF6 Axis in the Airway Epithelium.

House dust mites (HDMs) are a common source of respiratory allergens responsible for allergic asthma and innate immune responses in human diseases. Since HDMs are critical factors in the triggering of allergen-induced airway mucosa from allergic asthma, we aimed to investigate the mechanisms of Toll-like receptors (TLR) in the signaling of the HDM extract that is involved in mucus hypersecretion and airway inflammation through the engagement of innate immunity. Previously, we reported that the somatic nuclear autoantigenic sperm protein (sNASP)/tumor necrosis factor receptor-associated factor 6 (TRAF6) axis controls the initiation of TLRs to maintain the homeostasis of the innate immune response. The present study showed that the HDM extract stimulated the biogenesis of Mucin 5AC (MUC5AC) in bronchial epithelial cells via the TLR2/4 signaling pathway involving MyD88 and TRAF6. Specifically, sNASP binds to TRAF6 in unstimulated bronchial epithelial cells to prevent the activation of TRAF6-depenedent kinases. Upon on HDMs' stimulation, sNASP is phosphorylated, leading to the activation of TRAF6 downstream of the p38 MAPK and NF-κB signaling pathways. Further, NASP-knockdown enhanced TRAF6 signaling and MUC5AC biogenesis. In the HDM-induced mouse asthma model, we found that the HDM extract promoted airway hyperresponsiveness (AHR), MUC5AC, and allergen-specific IgE production as well as IL-5 and IL-13 for recruiting inflammatory cells. Treatment with the PEP-NASP peptide, a selective TRAF6-blocking peptide, ameliorated HDM-induced asthma in mice. In conclusion, this study indicated that the sNASP/TRAF6 axis plays a regulatory role in asthma by modulating mucus overproduction, and the PEP-NASP peptide might be a potential target for asthma treatment.

[Serum Lipid Levels and Their Prognostic Significance in Patients with Multiple Myeloma].

OBJECTIVE: To investigate the serum lipid levels and their prognostic significance in patients with multiple myeloma (MM). METHODS: A total of 87 newly diagnosed MM patients and 87 healthy controls in our hospital from January 2012 to April 2021 were selected. Serum lipid levels were compared between MM patients and healthy controls. The differences of serum lipid levels in patients among two groups of sex, age, hemoglobin (Hb), albumin (ALB), platelet (PLT), ß2-microglobulin (ß2-MG) and bone marrow plasma cell ratio (BMPC), different immune types, different ISS stages, before and after chemotherapy were analyzed. Univariate and COX multivariate regression analysis were used to analyze the influence of clinical parameters such as serum lipid indexes on prognosis of MM. RESULTS: The serum levels of total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), apolipoprotein A1 (Apo A1) and apolipoprotein B (Apo B) in MM patients were significantly lower than those in healthy controls (P<0.05). Anemia, low protein and low PLT in patients were related to low cholesterol. The levels of TC, LDL-C, HDL-C, Apo A1 and Apo B in patients with low Hb and ALB were significantly lower than those in patients with high Hb and ALB (P<0.05). The Apo B level of low PLT patients was significantly lower than that of high PLT patients (P<0.05). The levels of TC, LDL-C, HDL-C, Apo A1 and Apo B in patients with different immune types were significantly different, the above indexes of IgA type were significantly lower than IgG type(P<0.05), IgG type were significantly lower than light chain type(P<0.05), double clone type were significantly lower than light chain type (P<0.05). The levels of TC, LDL-C, and Apo B in patients with different ISS stages were significantly different, stage Ⅱ were lower than those of stage Ⅰ (P>0.05), stage Ⅲ were significantly lower than those of stage Ⅱ and stageⅠ(P<0.05). The levels of TC, TG, LDL-C, HDL-C, Apo A1 and Apo B in patients after chemotherapy were significantly higher than those before chemotherapy (P<0.05). Univariate analysis showed that Hb, PLT, ß2-MG, BMPC, LDL-C and Apo B affected the prognosis of MM. Multivariate analysis showed that BMPC and Apo B were independent factors affecting the prognosis of MM. CONCLUSION: The serum cholesterol level is decreased in MM patients, and hypocholesterolemia is related to the classification and staging of the disease. With the improvement of the disease, the serum cholesterol level is increased, and low serum Apo B level predicts a poor prognosis.

Ureteral calculi lithotripsy for single ureteral calculi: can DNN-assisted model help preoperatively predict risk factors for sepsis?

OBJECTIVES: To explore the utility of radiomics and deep learning model in assessing the risk factors for sepsis after flexible ureteroscopy lithotripsy (FURL) or percutaneous nephrolithotomy (PCNL) in patients with ureteral calculi. METHODS: This retrospective analysis included 847 patients with treatment-naive proximal ureteral calculi who received FURL or PCNL. All participants were preoperatively conducted non-contrast computed tomography scans, and relevant clinical information was meanwhile collected. After propensity score matching, the radiomics model was established to predict the onset of sepsis. A deep learning model was also adapted to further improve the prediction accuracy. Performance of these trained models was verified in another independent external validation set including 40 cases of ureteral calculi patients. RESULTS: The overall incidence of sepsis after FURL or PCNL was 5.9%. The least absolute shrinkage and selection operator (LASSO) regression analysis revealed 26 predictive variables, with an overall AUC of 0.881 (95% CI, 0.813-0.931) and an AUC of 0.783 (95% CI, 0.766-0.801) in external validation cohort. Judicious adaption of a deep neural network (DNN) model to our dataset improved the AUC to 0.920 (95% CI, 0.906-0.933) in the internal validation. To eliminate the overfitting, external validation was carried out for DNN model (AUC = 0.874 (95% CI, 0.858-0.891)). CONCLUSIONS: The DNN was more effective than the LASSO model in revealing risk factors for sepsis after FURL or PCNL in single ureteral calculi patients, and females are more susceptible to sepsis than males. Deep learning models have the potential to act as gatekeepers to facilitate patient stratification. KEY POINTS: • Both the least absolute shrinkage and selection operator (LASSO) and deep neural network (DNN) models were shown to be effective in sepsis prediction. • The DNN model achieved superior prediction capability, with an AUC of 0.920 (95% CI, 0.906-0.933). • DNN-assisted model has potential to serve as a gatekeeper to facilitate patient stratification.

Extracellular domain of semaphorin 5A serves a tumor­suppressing role by activating interferon signaling pathways in lung adenocarcinoma cells.

Semaphorin 5A (SEMA5A), which was originally identified as an axon guidance molecule in the nervous system, has been subsequently identified as a prognostic biomarker for lung cancer in nonsmoking women. SEMA5A acts as a tumor suppressor by inhibiting the proliferation and migration of lung cancer cells. However, the regulatory mechanism of SEMA5A is not clear. Therefore, the purpose of the present study was to explore the roles of different domains of SEMA5A in its tumor­suppressive effects in lung adenocarcinoma cell lines. First, it was revealed that overexpression of full length SEMA5A or its extracellular domain significantly inhibited the proliferation and migration of both A549 and H1299 cells using MTT, colony formation and gap closure assays. Next, microarray analyses were performed to identify genes regulated by different domains of SEMA5A. Among the differentially expressed genes, the most significant function of these genes that were enriched was the 'Interferon Signaling' pathway according to Ingenuity Pathway Analysis. The activation of the 'Interferon Signaling' pathway was validated by reverse transcription­quantitative PCR and western blotting. In summary, the present study demonstrated that the extracellular domain of SEMA5A could upregulate genes in interferon signaling pathways, resulting in suppressive effects in lung adenocarcinoma cells.

HIV-1 exposure promotes PKG1-mediated phosphorylation and degradation of stathmin to increase epithelial barrier permeability.

Exposure of mucosal epithelial cells to the human immunodeficiency virus type 1 (HIV-1) envelope glycoprotein gp120 is known to disrupt epithelial cell junctions by impairing stathmin-mediated microtubule depolymerization. However, the pathological significance of this process and its underlying molecular mechanism remain unclear. Here we show that treatment of epithelial cells with pseudotyped HIV-1 viral particles or recombinant gp120 protein results in the activation of protein kinase G 1 (PKG1). Examination of epithelial cells by immunofluorescence microscopy reveals that PKG1 activation mediates the epithelial barrier damage upon HIV-1 exposure. Immunoprecipitation experiments show that PKG1 interacts with stathmin and phosphorylates stathmin at serine 63 in the presence of gp120. Immunoprecipitation and immunofluorescence microscopy further demonstrate that PKG1-mediated phosphorylation of stathmin promotes its autophagic degradation by enhancing the interaction between stathmin and the autophagy adaptor protein p62. Collectively, these results suggest that HIV-1 exposure exploits the PKG1/stathmin axis to affect the microtubule cytoskeleton and thereby perturbs epithelial cell junctions. Our findings reveal a novel molecular mechanism by which exposure to HIV-1 increases epithelial permeability, which has implications for the development of effective strategies to prevent mucosal HIV-1 transmission.

Comparison of reduced field-of-view diffusion-weighted imaging (DWI) and conventional DWI techniques in the assessment of Cervical carcinoma at 3.0T: Image quality and FIGO staging.

OBJECTIVE: To evaluate imaging quality (IQ) and International Federation of Gynecology and Obstetrics (FIGO) staging of reduced field-of-view (r-FOV) diffusion-weighted imaging (DWI) in cervical carcinoma (CC). MATERIALS AND METHODS: Sixty patients with pathologically proven CC who underwent both pre-treatment r-FOV DWI and full field-of-view (f-FOV) DWI on a 3.0T MRI scanner were retrospectively reviewed. The subjective qualitative image scores were compared using the Wilcoxon signed-rank test. Objective quality values and apparent diffusion coefficient (ADC) were estimated by paired t-test or Wilcoxon signed-rank test for the two DWI sequences according to Normality test. Spearman rank correlation analysis was used to evaluate the relationship between pathological results and mean ADC value. RESULTS: The subjective IQ scores for r-FOV DWI were significantly higher than those for f-FOV DWI (P < 0.001). Similarly, the contrast-to-noise (CNR) value of r-FOV DWI was superior to that of f-FOV DWI (10.30 ±â€¯3.676, 8.91 ±â€¯3.008, P = 0.021). However, the signal-to-noise ratio (SNR) value of r-FOV DWI was considerably lower than that of f-FOV DWI (27.80 ±â€¯6.056, 33.67 ±â€¯7.833, P＜0.001). No significant difference was found between mean ADC values of f-FOV DWI and r-FOV DWI. There was a significant tendency for a negative correlation between the ADC values and FIGO stages of CC for both two sequences (r=-0. 436, P＜0.01; r=-0.470, P＜0.01, respectively). CONCLUSIONS: The rFOV DWI sequence provided significantly better IQ and lesion conspicuity than the fFOV DWI sequence. In addition, rFOV sequences can be used in evaluation of FIGO staging of cervical cancer.

Prediction of the World Health Organization Grade of rectal neuroendocrine tumors based on CT histogram analysis.

OBJECTIVES: To investigate the diagnostic value of contrast-enhanced computed tomography (CECT) histogram analysis in predicting the World Health Organization (WHO) grade of rectal neuroendocrine tumors (R-NETs). MATERIALS AND METHODS: A total of 61 (35 G1, 12 G2, 10 G3, and 4 NECs) patients who underwent preoperative CECT and treated with surgery to be confirmed as R-NETs were included in this study from January 2014 to May 2019. We depicted ROIs and measured the CECT texture parameters (mean, median, 10th, 25th, 75th, 90th percentiles, skewness, kurtosis, and entropy) from arterial phase (AP) and venous phase (VP) images by two radiologists. We calculated intraclass correlation coefficient (ICC) and compared the histogram parameters between low-grade (G1) and higher grade (HG) (G2/G3/NECs) by applying appropriate statistical method. We obtained the optimal parameters to identify G1 from HG using receiver operating characteristic (ROC) curves. RESULTS: The capability of AP and VP histogram parameters for differentiating G1 from HG was similar in several histogram parameters (mean, median, 10th, 25th, 75th, and 90th percentiles) (all p < 0.001). Skewness, kurtosis, and entropy on AP images showed no significant differences between G1 and HG (p = 0.853, 0.512, 0.557, respectively). Entropy on VP images was significantly different (p = 0.017) between G1 and HG, however, skewness and kurtosis showed no significant differences (p = 0.654, 0.172, respectively). ROC analysis showed a good predictive performance between G1 and HG, and the 75th (AP) generated the highest area under the curve (AUC = 0.871), followed by the 25th (AP), mean (VP), and median (VP) (AUC = 0.864). Combined the size of tumor and the 75th (AP) generated the highest AUC. CONCLUSIONS: CECT histogram parameters, including arterial and venous phases, can be used as excellent indicators for predicting G1 and HG of rectal neuroendocrine tumors, and the size of the tumor is also an important independent predictor.

[Inhibition of vegfr-2 gene expression by RNA interference].

This study was aimed to explore a novel potential gene target for therapy of malignant tumor. The recombinant expression plasmids of VEGF/VEGFR-2 were designed, constructed and then transfected into A549 cells by using lipofectamine. The expressions of VEGF/VEGFR-2 mRNA and protein were detected by RT-PCR and Western blot respectively. The cell proliferation was assayed by CCK-8 and the cell apoptosis was detected using Hoechst Staining. The results indicated that as compared with the blank control, pGenesil-1 and scramble groups, the interference effect of pGenesil-1-vegfr-2-shRNA-1 vector group was more obvious. As the expression of endogenous vegfr-2 mRNA decreased, the expression of VEGFR-2 protein decreased correspondingly. The proliferation of A549 cells was inhibited significantly by RNAi at 72 hours (p<0.01). The apoptosis of A549 cells was induced at 48 hours after being transfected with pGenesil-1-vegfr-2-shRNA-1 and the typical apoptosis morphology could be seen by fluorescence microscopy. It is concluded that the expression of vegfr-2 gene is inhibited effectively by vegfr-2 specific shRNA. The proliferation of A549 cells is inhibited significantly and the apoptosis of cells is induced. This result showed that VEGF/VEGFR-2 signaling pathway can be an effective target for the prevention and treatment of malignant tumor.

[Dynamic analysis of expression of VEGF and its receptor-2 in mouse model with acute myeloid leukemia].

The objective of study was to explore the role of vascular endothelial growth factor (VEGF) and its receptor-2 in pathogenesis of acute myeloid leukemia. The acute myeloid leukemia model was established on 20 mice with severe combined immunodeficiency (SCID) transplanted by HL-60 cells. The mice were divided into the normal control and test group randomly. The expression of VEGF was detected by enzyme linked immunosorbent assay (ELISA). The expression of VEGFR-2 mRNA was detected by RT-PCR. The results showed that the establishment of acute myeloid leukemia model was succeeded on all SCID mice by HL-60 cell transplantation. The expressions of VEGF and VEGFR-2 mRNAs could be determined on all mice. As compared with the normal control group, the expressions of VEGF and VEGFR-2 mRNAs in the test group significantly increased, but gradually increased during the course of disease. It is concluded that the abnormal expressions of VEGF and VEGFR-2 exist in mice with acute myeloid leukemia, which may be involved in the pathogenesis of AML.

[The clinical study of the damage of visual function caused by pituitary tumor].

PURPOSE: To investigate the clinical manifestation of damage of visual function caused by pituitary adenoma. METHODS: Visual acuity, visual field, fundus fluorescein angiography (FFA), pattern visual evoked potential (PVEP) and examination fundus were performed in 126 cases (252 eyes) of pituitary tumor. RESULTS: There was 73.8% (186 eyes) of patients with decreased visual acuity, 51.6% (130 eyes) with primary optic atrophy, 69.6% (156 eyes) with the defects of visual field and 88.9% (160 eyes) with abnormal PVEP. Abnormal ophthalmological manifestation was the first diagnostic symptom in 26.2%, and 16.7% was misdiagnosed as eye diseases. CONCLUSIONS: Pituitary tumor could cause defection of visual function. It is helpful to early diagnosis and timely treatment by fully understanding clinical features in the eye with pituitary tumor.

[Effect of fas mRNA expression on cytochrome C-induced apoptosis of HL-60 cells in vitro].

The aim of this study was to investigate the effect of cytochrome C on apoptosis of HL-60 cells and to explore the mechanism of HL-60 cell apoptosis induced by cytochrome C. The HL-60 cells were treated with different concentrations of cytochrome C for 24 hours. The concentrations of cytochrome C were as follows: 0 (control group), 9.375 mg/L, 18.75 mg/L, 37.5 mg/L, 75 mg/L and 150 mg/L. The apoptosis was analyzed by flow cytometry (FCM) after HL-60 cells were treated with different concentrations of cytochrome C for 24 hours. The fas mRNA expression changes of relevant apoptotic genes were examined by reverse transcription-polymerase chain reaction (RT-PCR) after HL-60 cells were treated with different concentrations of cytochrome C for 24 hours and were analyzed half-quantitatively. The expressions of fas involved in HL-60 treated with different concentrations of cytochrome C for 24 hours were detected by Western blot. The results indicated that the flow cytometry (FCM) (PI straining) showed obvious hypo-diploid peak before G(1) phase in the treated group, and its apoptotic ratio increased in a dose-dependent manner. The fas mRNA expression levels of the relevant apoptotic genes could be detected by RT-PCR after HL-60 cells treated with different concentrations of cytochrome C for 24 hours, and the expression of fas mRNA in HL-60 cells was increased by cytochrome C in dose-dependent manner within range of 0-37.5 mg/L. It is concluded that the cytochrome C up-regulates expressions of fas mRNA and their protein so as to induce apoptosis of the HL-60 cells.

[Effect of cytochrome C on HL-60 cell apoptosis and its relationship with the relevant genes bcl-2 and bax].

To study the effect of cytochrome C on HL-60 cells in vitro and the mechanism of expression changes of relevant apoptotic genes, the inhibition rate of cytochrome C on HL-60 cells was detected by MTT, the morphology of HL-60 cells was observed by light microscopy and fluorescence microscopy, the changes of apoptosis rate and cell cycle were assayed by flow cytometry (FCM), DNA ladder was investigated on electrophoresis, the expression changes of bax and bcl-2 mRNA were examined by RT-PCR, when HL-60 cells were treated with different concentrations of cytochrome C for 24 hours. The results showed that the inhibition rate increased with increase of the cytochrome C concentration within 0 - 150 mg/L; when treated with 0 - 37.5 mg/L cytochtome C for 24 hours, the percentage of apoptotic HL-60 cells increased with the dose increasing, and the typical apoptotic cells and the apoptotic DNA ladder were observed. At the same time, within this range of concentration, the expression of bcl-2 mRNA decreased gradually and the expression of bax increased gradually. When the cytochrome C concentration was higher than 37.5 mg/L, the percentage of apoptotic HL-60 cells not increased, but decreased, while the cells necrosed. The above metioned results suggested that at certain range of concentration of cytochrome C, apoptosis or necrosis can be induced by cytochrome C, and cell cycle arrests at G(1) phase in HL-60 cells, the percentage of apoptotic cells and the changes of expression of bax and bcl-2 depend on the dose of cytochrome C. The mechanism that cytochtome C induced apoptosis in HL-60 cells may be related to the activation of bax and inhibition of bcl-2.

[Influence of cytochrome C on apoptosis induced by daunorubicine in acute myeloid leukemia (AML) cells].

The purpose was to study the responses of AML cell treated with cytochrome C and to explore the influence of cytochrome C on apoptosis of AML cell induced by daunorudicine (DNR). The differentiation of AML cell was detected by Wright-Giemsa staining and NBT test, the apoptosis of AML cell was assayed by flow cytometry and fluorescence microscopy. The results showed as follows: (1) different concentrations of cytochrome C could induce different effects on AML cells. Concentration of cytochrome C for differentiation was 10 microl/ml, for apoptosis was 20 microl/ml, and for necrosis was 40 microl/ml. (2) the apoptosis of AML cells decreased with the administration of cytochrome C in 10.0 microg/ml before treating AML cells with DNR (P < 0.01), but no change was shown with the administration of cytochrome C in 20.0 microg/ml (P > 0.05). (3) in reverse sequence, administrating of cytochrome C in 10 microl/ml and 20 microl/ml after treating AML cells with DNR, two different concentrations of cytochrome C could increase the apoptosis of AML cells (P < 0.01). It is suggested that cytochrome C may probably affect the apoptosis of AML cells induced by DNR.

[Effect of IL-15 on the proliferation and differentiation of CD34+ cells from MDS patients].

AIM: To explore the effect of IL-15 on proliferation and differentiation of CD34 (+) cells from MDS patients. METHODS: The CD34 (+) cells were separated by magnetic bead-activated cell sorter (MACS) system, and cultured in fluid or methylcellulose semisolid medium. MTT colorimetry was used to examine the inhibitory effect of IL-15 on the proliferation of MDS CD34(+) cells.The numbers of CD34(+)cells and colony formation of CFU-E, BFU-E, CFU-G, CFU-GEMM were counted. The expressions of CD33, CD13, CD71, CD19 and CD3 on cultured cells and the change of cell-cycle were analyzed by FCM. RESULTS: The recovery rate of CD34(+) cells was (75.4+/-5.2) %, the purity of CD34 (+) cells in positive fraction was (90.3+/-6.3) % and the enriched rate was (83.1+/-12.5) % in 11 MDS patients. MTT colorimetry detection showed that IL-15 could promote the proliferation of MDS CD34(+) cells. The optimal time of promotoing CD34(+) cell proliferation by IL-15 was 8 days and optimal dosage of IL-15 was 20 microg/L. After culture for 8 days with 0 microg/L IL-15 (control group) and 20 microg/L IL-15(experimental group), the number of CD34 (+) cells increased by 4.6-fold in control group and 6.3-fold in experimental group (P<0.05, n=5). The colony formation rates of experimental group were significantly higher than those of control group. The expression rates of the CD molecules (except for CD3) on CD34(+) in experimental group were notably higher than those in control group. As compared with control group, much more CD34(+) cells of experimental group were in G(2) and S phase of cell cycle(P<0.05, n=7). CONCLUSION: IL-15 can obviously promote the proliferation and differentiation of CD34(+) cells from MDS patients.

[Microsurgical technique of brain glioma---a report of 183 cases].

BACKGROUND & OBJECTIVE: Prognosis of glioma is still poor, its main treatment is surgery. The extent of tumor resection relates with prognosis. This study was to evaluate the extent of resection, post-operative Karnofsky performance scale (KPS), and survival rate of the glioma patients received microsurgery. METHODS: Records of 183 glioma patients received microneurosurgery were retrospectively analyzed, the extent of resection, post-operative KPS, and survival rate of patients were evaluated. Different microsurgical techniques were applied according to the location of gliomas. En bloc resection was performed for gliomas in non-functional areas by dissecting the tumors along edema area with high-power bipolar electrocoagulation. The tumors in functional areas were separated along cortex sulcus, the central part of tumor was removed firstly, and residual part was resected with low-power electrocoagulation. Gliomas close to important vessels were sucked, and electrocoagulation seldom performed. RESULTS: Among 183 cases of glioma, 85 in non-functional area, 47 in functional area, and 51 close to important vessels. Total and sub-total resection was performed in 163 patients (89.1%). The average post-operative KPS was 74. The KPS was decreased in 23 patients, increased in 44 patients, and stable in 116 patients. Patients were followed up for 12-216 months with an average of 47.8 months. The follow-up rate was 100%. Among 113 patients with long-term follow-up (>/=5 years), 5-year survival rates of low-grade, and high-grade astrocytoma patients were 75.4% (52/69), and 18.2% (8/44). CONCLUSION: Using different microsurgical patterns according to location of glioma, maximal resection of tumor may achieve with protection of neurological function.

[Controlled pathological study and preoperative MRI evaluation of the consistency of pituitary adenomas].

BACKGROUND & OBJECTIVE: Consistency of pituitary adenoma may influence surgical remote of the tumor. Preoperative evaluation of tumor consistency will be useful in guiding the operative approach. This study was designed to investigate the relationship among pituitary adenoma consistency, collagen type I and MRI signal intensity. METHODS: Twenty pituitary adenoma patients received transsphenoidal surgery. Preoperative MRI, H-E stains and collagen type I immunohistochemistry(IHC)-autonomic image analysis for tumor specimens were performed RESULTS: Ten tumors were soft, mean T2WI tumor/while matter signal intensity ratio (TWSIR) is 17.38%; six were moderate, mean T2WI TWSIR was 2.01; and 4 were firm, mean T2WI TWSIR was 1.56. Mean collagen type I positive area ratio(CIPAR) of soft, moderate, and firm tumors was 17.38%, 27.30%, and 40.31%, respectively. Both C1PAR and T2WI TWSIR were significantly different among three types (P < 0.01) C1PAR was negatively correlated to T2WI TWSIR(P < 0.01). CONCLUSION: Collagen type I content relates with the consistency of pituitary adenomas. MRI can predict of pituitary consistency adenoma; and those show hypointensity in T2WI are firm.