Low-valent-tungsten catalysis enables hydroboration of esters and nitriles

In the research presented herein, low-valent-tungsten-catalyzed hydroboration of esters and nitriles was investigated. Aromatic and aliphatic substrates were smoothly reduced to corresponding alcohol derivatives and N,N-diborylamines in the presence of W(CO)4(NCMe)2. Valuable derivatives were conveniently accessed by introducing a further functionalization process to crude hydroboration mixtures in one pot.

Zwitterionic Aqua Palladacycles with Noncovalent Interactions for meta-Selective Suzuki Coupling of 3,4-Dichlorophenol and 3,4-Dichlorobenzyl Alcohol in Water

The site-selective reaction of substrates with multiple reactive sites has been a focus of the current synthetic chemistry. The use of attractive noncovalent interactions between the catalyst and substrate is emerging as a versatile approach to address site-selectivity challenges. Herein, we designed and synthesized a series of palladacycles, to control meta-selective Suzuki coupling of 3,4-dichlorophenol and 3,4-dichlorobenzyl alcohol. Noncovalent interactions directed zwitterionic aqua palladacycles catalyzed meta-selective Suzuki couplings of 3,4-dichloroarenes bearing hydroxyl in water have been developed. Experiments and density functional theory (DFT) calculations demonstrated that the electrostatic interactions play a critical role in meta-selective coupling of 3,4-dichlorophenol, while meta-selective coupling of 3,4-dichlorobenzyl alcohol arises due to the hydrogen-bonding interactions.

[Efficacy and safety analysis of an improved overlength biliary stent in the treatment of biliary stricture]

Objective: To evaluate the efficacy and safety of an improved overlength biliary stent in the treatment of bile duct stricture. Methods: Prospective randomized controlled study. Patients with bile duct stricture in Peking University International Hospital from February 2016 to June 2021 were randomly divided into the conventional plastic biliary stents (CPBS) group and the improved overlength biliary stents (IOBS) group by envelope random method. CPBS or IOBS were placed after endoscopic retrograde cholangiopancreatography (ERCP) breast catheterization was successfully conducted and the stenosis length was determined by angiography. The incidence of postoperative complications, median patency time of postoperative stent and reoperation rate within 6 months were compared between the two groups, Kaplan-Meier method was used to draw the survival curve, and log-rank test was conducted to evaluate the safety and efficacy of IOBS in the treatment of bile duct stricture. Results: A total of 90 patients were included. There were 45 patients in IOBS group, including 28 males and 17 females, aged (67.2±11.7) years. There were 45 patients in CPBS group, including 26 males and 19 females, aged (64.6±14.4) years. The patients in the both groups were balanced and comparable. There were no significant differences in success rate of operation, operation time, hospitalization time, operation cost and prospective complication rate between the two groups (all P>0.05). There were no significant differences in the changes of liver function index before and 72 hours after operation between the two groups (both P>0.05). The median patency time of stents in IOBS group was longer than that in CPBS group [M(Q1, Q3), 201(155,246) vs 109(55,167) d, P=0.002].The IOBS group had lower reoperation rate than the CPBS group within 6 months [46.2% (18/39) vs 78.9%(30/38), P=0.003]. Conclusion: IOBS has good safety in the treatment of bile duct stricture and the clinical efficacy is superior to CPBS.

[Prognostic factors for non-small cell lung cancer patients with central nervous system metastasis with positive driver genes]

Objective: To investigate the prognostic factors of patients with central nervous system (CNS) metastatic non-small cell lung cancer (NSCLC) with positive driver genes. Methods: The clinical data of 103 patients with CNS metastatic NSCLC admitted to Beijing Tongren Hospital from January 2016 to December 2020 were retrospectively analyzed, and the patients were divided into positive driver gene group (patients with driver genes mutation and receiving corresponding targeted therapy) and negative driver gene group. Cox univariate and multivariate regression analyses were performed to identify the factors affecting patients' prognosis, and the receiver operating characteristic curve (ROC) was used to compare the predictive ability of 4 scoring systems [recursive partitioning analysis (RPA) classes, diagnosis-specific graded prognostic assessment (DS-GPA) index, basic score for brain metastasesn (BS-BM) and (lung-molecular graded prognostic assessment (lung-mol GPA)]on patients' prognosis. Results: Among the 103 patients, 48 were males and 55 were females, and aged (64.6±9.7) years old. The median survival time of the 103 patients was 24.0 (95%CI: 20.0-28.0) months, the median survival time of the 59 patients in the positive driver gene group was 33.0 (95%CI: 23.4-42.6) months, the median survival time of the 44 patients in the negative driver gene group was 17.0 (95%CI: 14.4-19.6) months, and the difference was statistically significant (χ²=24.69, P<0.001). The results of Cox multivariate analysis showed that the negative driver genes (HR=3.788, 95%CI: 1.951-7.301, P=0.001), Karnofsky performance status (KPS) score<70 (HR=2.613, 95%CI: 1.185-5.761, P=0.017) and neutrophil-to-lymphocyte ratio (NLR)>3.22 (HR=2.714, 95%CI: 1.157-6.365, P=0.022) were independent risk factors affecting the prognosis of patients with CNS metastatic NSCLC. KPS score<70 (HR=3.719, 95%CI: 1.165-11.876, P=0.027) and no radiotherapy (HR=2.032, 95%CI: 1.033-11.364, P=0.041) were independent risk factors affecting the prognosis of patients with CNS metastatic NSCLC with positive driver genes. ROC curve analysis showed that the area under curve (AUC) value of lung-mol GPA was the highest among the 4 scoring systems (AUC=0.843, 95%CI: 0.731-0.956, P<0.001), and the AUC value of the lung-mol GPA combined scoring system (AUC=0.904, 95%CI: 0.816-0.991, P<0.001) was higher than lung-mol GPA. Conclusions: A low KPS score and no cranial radiation therapy are independent risk factors for the prognosis of patients with CNS metastatic NSCLC with positive driver genes; the lung-mol GPA joint scoring system is more conducive to the prognostic assessment of patients with CNS metastatic NSCLC with positive driver genes.

Development and validation of risk prediction models for stroke and mortality among patients with type 2 diabetes in northern China

BACKGROUND

Stroke is one of the leading causes of disability and mortality in patients with type 2 diabetes mellitus (T2DM). Risk models have been developed for predicting stroke and stroke-associated mortality among patients with T2DM. Here, we evaluated risk factors of stroke for individualized prevention measures in patients with T2DM in northern China.

METHODS

In the community-based Tianjin Chronic Disease Cohort study, 58,042 patients were enrolled between January 2014 and December 2019. We used multiple imputation (MI) to impute missing variables and univariate and multivariate Cox's proportional hazard regression to screen risk factors of stroke. Furthermore, we established and validated first-ever prediction models for stroke (Model 1 and Model 2) and death from stroke (Model 3) and evaluated their performance.

RESULTS

In the derivation and validation groups, the area under the curves (AUCs) of Models 1-3 was better at 5 years than at 8 years. The Harrell's C-index for all models was above 0.7. All models had good calibration, discrimination, and clinical net benefit. Sensitivity analysis using the MI dataset indicated that all models had good and stable prediction performance.

CONCLUSION

In this study, we developed and validated first-ever risk prediction models for stroke and death from stroke in patients with T2DM, with good discrimination and calibration observed in all models. Based on lifestyle, demographic characteristics, and laboratory examination, these models could provide multidimensional management and individualized risk assessment. However, the models developed here may only be applicable to Han Chinese.

Markedly decreased growth rate and biofilm formation ability of Acinetobacter schindleri after a long-duration (64 days) spaceflight

OBJECTIVE

The objective of this study was to investigate the effects of long-duration space flight on the biological characteristics of Acinetobacter schindleri (A. schindleri).

MATERIALS AND METHODS

In this study, an A. schindleri strain was collected from condensate water of the Shenzhou-10 spacecraft and then was sent into space again to the Tiangong-2 space lab for a long-duration spaceflight (64 days). Later, the impacts of the long-duration spaceflight on phenotype, genome and transcriptome of A. schindleri were analyzed.

RESULTS

It was found that the long-duration spaceflight markedly decreased the growth rate and biofilm formation ability of A. schindleri. Furthermore, comparative genomic and transcriptomic analyses revealed that the decreased growth rate might be associated with differentially expressed genes (DEGs) involved in transmembrane transport, energy production and conversion, and biofilm was reduced due to downregulation of the pil and algR genes.

CONCLUSIONS

The findings are of major importance for predicting bacterial pathogenesis mechanisms and possible spacecraft contamination during long-duration spaceflights in the future.

Taxamat: Automated biodiversity data management tool - Implications for microbiome studies

Working with biodiversity data is a computationally intensive process. Numerous applications and services provide options to deal with sequencing and taxonomy data. Professional statistics software are also available to analyze these type of data. However, in-between the two processes there is a huge need to curate biodiversity sample files. Curation involves creating summed abundance values for chosen taxonomy ranks, excluding certain taxa from analysis, and finally merging and downsampling data files. Very few tools, if any, offer a solution to this problem, thus we present Taxamat, a simple data management application that allows for curation of biodiversity data files before they can be imported to other statistics software. Taxamat is a downloadable application for automated curation of biodiversity data featuring taxonomic classification, taxon filtering, sample merging, and downsampling. Input and output files are compatible with most widely used programs. Taxamat is available on the web at http://www.taxamat.com either as a single executable or as an installable package for Microsoft Windows platforms.

[Operative efficacy of 13 malignant uterine tumors after Cf-252 intracavitary irradiation]

Objective: To investigate the surgical therapeutic efficacy of uterine tumors patients underwent Cf-252 neutron intra-cavity and external radiotherapy, and evaluate the application value of Cf-252 neutron radiotherapy. Methods: Thirteen cases of uterine tumor with local suspicious lesions or poor prognostic factors after CF-252 neutron intracavity and external radiotherapy were treated with surgery. Among them, 12 cases underwent extrafascial hysterectomy, 1 case underwent extensive hysterectomy and lymphadenectomy. The postoperative pathology and follow-up results were used to evaluate the efficacy. Results: Nine cases showed severe response to radiotherapy in postoperative cervical pathological tissues without residual tumor, and survived for more than 3-14 years, the median survival time was 8 years. All of 4 cases with residual tumor died within 1 year. Delayed healing of vaginal wounds occurred in 3 of the 12 cases. Conclusions: Cf-252 is a good brachytherapy source. The cervical tissue shows severe response to radiotherapy and prolonged healing time of vaginal wound is observed in some cases after CF-252 radiotherapy. To those uterine tumor patients with local suspicious lesions or poor prognostic factors after CF-252 neutron intracavity and external radiotherapy, extrafascial hysterectomy is a safe and feasible treatment method.

Fecal expression of Escherichia coli lysine decarboxylase (LdcC) is downregulated in E-cadherin negative lobular breast carcinoma

Breast cancer is characterized by oncobiosis, the abnormal composition of the microbiome in neoplastic diseases. The biosynthetic capacity of the oncobiotic flora in breast cancer is suppressed, as suggested by metagenomic studies. The microbiome synthesizes a set of cytostatic and antimetastatic metabolites that are downregulated in breast cancer, including cadaverine, a microbiome metabolite with cytostatic properties. We set out to assess how the protein expression of constitutive lysine decarboxylase (LdcC), a key enzyme for cadaverine production, changes in the feces of human breast cancer patients (n = 35). We found that the fecal expression of Escherichia coli LdcC is downregulated in lobular cases as compared to invasive carcinoma of no special type (NST) cases. Lobular breast carcinoma is characterized by low or absent expression of E-cadherin. Fecal E. coli LdcC protein expression is downregulated in E-cadherin negative breast cancer cases as compared to positive ones. Receiver operating characteristic (ROC) analysis of LdcC expression in lobular and NST cases revealed that fecal E. coli LdcC protein expression might have predictive values. These data suggest that the oncobiotic transformation of the microbiome indeed leads to the downregulation of the production of cytostatic and antimetastatic metabolites. In E-cadherin negative lobular carcinoma that has a higher potential for metastasis formation, the protein levels of enzymes producing antimetastatic metabolites are downregulated. This finding represents a new route that renders lobular cases permissive for metastasis formation. Furthermore, our findings underline the role of oncobiosis in regulating metastasis formation in breast cancer.

[Comparison of endoscopic features between colorectal sessile serrated adenoma/polyp with or without cytologic dysplasia and hyperplastic polyp]

Objective: To investigate the morphological features of colorectal sessile serrated adenoma/polyp (SSA/P) and hyperplastic polyp (HP) by white light endoscope (WLE) and Image enhancement endoscope (IEE) . Methods: The data of 7 384 patients who underwent colonoscopy at the Center of Digestive Endoscopy, Peking University International Hospital from August 1, 2016 to February 29, 2018 were analyzed retrospectively. WLE and IEE[Fuji intelligent chromo endoscopy (FICE) or Blue Laser Imaging (BLI) ]were used to compare the morphological features of SSA/P with HP, SSA/P-CD(+)with SSA/P-CD(-). The diagnostic values of endoscopic features in SSA/P and SSA/P-CD(+)were analyzed. Results: A total of 3 401 polyps were detected in 7 384 patients, including 164 SSA/Ps (135 patients). During the same period, there were 270 HPs (223 patients) in accordance with the admission criteria. Compared with HP group, SSA/P group was more common in the right colon with a diameter>5 mm and more likely to be manifested as: Ⅱ-O pit pattern, surface mucus, cumulus-like surface, irregular morphology, VMV, redness, and also more likely to be associated with colon adenoma, colon cancer elsewhere in the colorectum. The differences were statistically significant (P<0.01). Compared with SSA/P-CD(-)group, SSA/P-CD(+)group was more common in the right colon with a diameter>5 mm and more likely to be manifested as: Ⅱ-O pit pattern, surface mucus, cumulus-like surface, irregular morphology, VMV. The differences were statistically significant (P<0.001). The differential diagnosis between SSA/P and HP was predicted by combining any two endoscopic morphological features (right colon, Ⅱ-O pit pattern, surface mucus, cumulus surface, irregular morphology, VMV, diameter>5 mm, at least 2 of 7 endoscopic features). The sensitivity, specificity, accuracy, positive likelihood ratio and negative likelihood ratio were 59.15%, 95.56%, 81.80%, 13.32 and 0.43, respectively. Similarly, the differential diagnosis between SSA/P-CD(+) and HP was predicted. The sensitivity, specificity, accuracy, positive likelihood ratio and negative likelihood ratio were 92.16%, 95.56%, 95.02%, 20.76 and 0.08, respectively. Conclusion: Comprehensive analysis of the WLE and FICE/BLI morphological features of the lesions can effectively distinguish SSA/P from HP, especially SSA/P-CD(+) from HP.

[The clinicopathologic parameters and prognostic analysis of vulvar squamous cell carcinoma]

Objective: To evaluate the significance of different clinicopathologic features on prognosis of patients with squamous cell carcinoma of vulva. Methods: We retrospectively analyzed the prognostic relevance of different clinicopathological variables of 201 patients with squamous cell carcinoma of vulva treated in Cancer Hospital, Chinese Academy of Medical Sciences. The data including age, initial symptoms, stage, location, tumor size, histological grade, number and size of metastatic lymph nodes, treatment mode, and presence of leukoplakia vulva was used to evaluate the prognosis of vulvar squamous cell carcinoma. Results: The median age of onset was 62.0 years old, with 74 patients in stage Ⅰ, 27 in stage Ⅱ, 55 in stage Ⅲ and 9 in stage Ⅳ. The median progression-free survival was 90.0 months. The 5-year progression-free survival rate of the total patients was 55.5%, while the 10-year progression-free survival rate was 48.5%. Univariate analysis showed statistically significant prognostic parameters included clinical stage, number of metastatic lymph nodes, tumor size and treatment mode (all P<0.001). Multivariate analysis showed that number of metastatic lymph nodes (P<0.05) was an independent prognostic factor for progression-free survival. Conclusion: The study illustrates that number of metastatic lymph nodes represents important independent factor for progression-free survival of patients with vulvar squamous cell carcinoma.

[A comparative study of cold snare and hot snare resection of small colorectal polyps]

Objective: To compare the effect of cold snare and hot snare on the resection of small colorectal polyps, and to explore the clinical value of cold snare technique in removing colorectal polyps. Methods: From September 1, 2017 to January 31, 2018, 206 cases of patients with colorectal polyp resection in the Department of Gastroenterology of Peking University International Hospital were studied. During this period, according to the standard, 103 cases of patients (158 polyps) were in the cold snare group, and 103 patients (180 polyps) were randomly selected as control group from patients of the hot snare group. The related clinical data were analyzed retrospectively. The location, shape, size, polypectomy time, pathological type, complete resection rate, specimen recovery rate, complications and related costs of the two groups of polyps were compared. Results: The polypectomy time of the cold snare group was shorter than that of the hot snare group.The difference was statistically significant (Z=-11.727, P<0.001). The related cost of the perioperative period of the cold snare group was lower than that of the hot snare group.The difference was statistically significant (Z=-12.680, P<0.001). There were no statistically significant differences in the number of polyps/case, size, shape, pathological classification, complete resection rate, specimen recovery rate, and perioperative complications of the patients in the two groups(P>0.05). Conclusions: The operation time of cold snare technique in colorectal polyps (6-9 mm in diameter) is shorter and the cost is lower, which is worthy of clinical promotion.

[Regulation of Ruxolitinib on matrix metalloproteinase in JAK2V617F positive myeloroliferative neoplasms cells]

Objective: To investigate the regulation of JAK2 tyrosine kinase inhibitor ruxolitinib on extracellular matrix metalloproteinase (MMP in JAK2V617F positive myeloproliferative neoplasms (MPN) cells. Methods: ①Forty cases of newly diagnosed JAK2V617F positive MPN patients and 15 healthy volunteers as control in Baoding No.1 Hospital between January 2012 and December 2015 were enrolled in this study. JAK2V617F/JAK2 ratio was detected by real-time-PCR; the expression levels of phosphorylation protein tyrosine kinase 2 (p-JAK2) , MMP-2 and MMP-9 in pathological tissues of bone marrow were detected by immunohistochemistry. The bone marrow cells of JAK2V617F positive MPN patients were treated with ruxolitinib, then the migration ability and MMP-2, MMP-9 gene and protein expression levels were detected. ②The human erythroleukemia cell line HEL cells were treated with different concentrations of ruxolitinib (0, 50, 100, 250, 500, 1 000 nmol/L) . The cell viability was detected by CCK-8 test; cell migration ability was tested by transwell chambers. The mRNA expression levels of JAK2, MMP-2 and MMP-9 were detected by real-time-PCR. The protein expression levels of p-JAK2, MMP-2 and MMP-9 were detected by Western blot. Results: ①The expression levels of p-JAK2, MMP-2 and MMP-9 in the newly diagnosed group were significantly higher than control group respectively [ (78.56±24.55) % vs (41.59±17.29) %, P<0.05; (48.25±18.74) % vs (22.79±13.89) %, P<0.05; (53.29±19.28) % vs (15.56±14.96) %, P<0.05]. Spearman correlation analysis showed the positive correlation of MMP-2 and MMP-9 protein expression levels with JAK2V617F mutation (r=0.526, P=0.001; r=0.543, P=0.001) . ②The proliferation of HEL cells was inhibited by different concentrations of ruxolitinib in time and dose dependent manner. ③Cell migration test showed the number of cells leaked to the low chamber in MPN patients bone marrow cells and HEL cells treated with 5 nmol/L of ruxolitinib group were significantly lower than that without ruxolitinib treatment after 24 h [ (154.7±27.5) vs (320.3±67.3) , t=13.47, P<0.05; (70.7±10.5) vs (135.3±16.7) , t=13.89, P<0.05]. The mRNA and protein expression levels of JAK2, MMP-2 and MMP-9 decreased with the increased concentration of ruxolitinib. Conclusion: Ruxolitinib inhibits MPN cell migration and expression of MMP-2 and MMP-9 via JAK2 signal pathway.

[Prognostic analysis of stage Ⅰb2 andⅡa2 cervical squamous cancer without high risk factors treated with neo-adjuvant chemotherapy and radical hysterectomy]

Objective: To analyze the prognosis of Ⅰb2 and Ⅱa2 cervical squamous cancer without high risk factors treated with neo-adjuvant chemotherapy (NACT) and radical hysterectomy. Methods: This retrospective study included patients with International Federation of Gynecology and Obstetrics (FIGO) stage Ⅰ b2 and Ⅱ a2 cervical squamous cancer without high risk factors who underwent platinum-based NACT followed by radical surgery from January 2008 to January 2015. The responses of NACT were observed and compared in their effect on postoperative pathologic risk factors. Kaplan-Meier method and Cox regression analysis were performed to analyze survival status. Results: This study was recruited 282 patients with the average age of (44.4±6.7) years old. After NACT, 42 patients achieved complete response [CR, 14.9% (42/282) ], while 138 patients achieved partial response [PR, 48.9% (138/282) ] and 102 stable disease [SD, 36.2% (102/282) ]. The rate of pathologic diameter ≥4 cm, deep stromal invasion (DSI) positive and lymph-vascular space invasion (LVSI) positive rate decreased significantly in CR and PR group compared with SD group (P<0.05) . The number of postoperative risk factors in CR, PR and SD groups varied significantly (χ(2)=64.869, P=0.000) . Besides, the rate of multiple intermediate risk factors was respectively 0 vs 13.8% vs 45.1% (χ(2)=7.107, P=0.008) . The disease relapsed in 23 patients, and 12 died. On the whole series, 5-year overall survival rate was 91.7%, and 5-year recurrence-free survival rate was 88.9%. The rate of recurrence (P=0.002) and mortality (P=0.036) were higher in LVSI positive patients compared with LVSI negative. And the rate of recurrence was higher in patients with multiple intermediate risk factors, compared with no or one intermediate risk factors (P=0.002) . Univariate analysis revealed that LVSI positive and multiple intermediate risk factors were the factors predicted recurrence and mortality (P<0.05) , and no significance in age, stage, tumor grade, tumor diameter before or after NACT, response to NACT, or DSI positive factors (all P>0.05) . The multivariate analysis showed that, the factor of primary tumor diameter ≥6 cm (P=0.022) and multiple intermediate risk factors (P=0.001) were independent prognostic variables for recurrent-free survival. Besides, multiple intermediate risk factors was independent prognostic variable for overall survival (P=0.034) . After surgery, 107 patients did not receive adjuvant therapy, while 175 patients received adjuvant therapy with 26 radiotherapy, 46 chemotherapy and 103 concurrent radiochemotherapy. On survival analysis of postoperative adjuvant treatment, 5-year recurrence-free survival rate of radiotherapy group was significantly lower in patients with the factor of SD response to NACT (P=0.011) and multiple intermediate risk factors (P=0.008) , while overall no significance in overall survival rate (P>0.05) . Conclusions: NACT may be play beneficial role in relieving the status of intermediate risk factors for stage Ⅰ b2 and Ⅱ a2 cervical squamous cancer without high risk factors. The status of multiple intermediate risk factors is independent prognostic factors for recurrence and mortality. For patients with multiple intermediate risk factors, postoperative adjuvant chemotherapy or concurrent radiochemotherapy might be the better choice to prevent relapse.

Clozapine modifies the differentiation program of human adipocytes inducing browning

Administration of second-generation antipsychotic drugs (SGAs) often leads to weight gain and consequent cardio-metabolic side effects. We observed that clozapine but not six other antipsychotic drugs reprogrammed the gene expression pattern of differentiating human adipocytes ex vivo, leading to an elevated expression of the browning marker gene UCP1, more and smaller lipid droplets and more mitochondrial DNA than in the untreated white adipocytes. Laser scanning cytometry showed that up to 40% of the differentiating single primary and Simpson-Golabi-Behmel syndrome (SGBS) adipocytes had the characteristic morphological features of browning cells. Furthermore, clozapine significantly upregulated ELOVL3, CIDEA, CYC1, PGC1A and TBX1 genes but not ZIC1 suggesting induction of the beige-like and not the classical brown phenotype. When we tested whether browning induced by clozapine can be explained by its known pharmacological effect of antagonizing serotonin (5HT) receptors, it was found that browning cells expressed 5HT receptors 2A, 1D, 7 and the upregulation of browning markers was diminished in the presence of exogenous 5HT. Undifferentiated progenitors or completely differentiated beige or white adipocytes did not respond to clozapine administration. The clozapine-induced beige cells displayed increased basal and oligomycin-inhibited (proton leak) oxygen consumption, but these cells showed a lower response to cAMP stimulus as compared with control beige adipocytes indicating that they are less capable to respond to natural thermogenic anti-obesity cues. Our data altogether suggest that novel pharmacological stimulation of these masked beige adipocytes can be a future therapeutic target for the treatment of SGA-induced weight gain.

[Hormonal therapy of advanced or relapsed ovarian granulosa cell tumor]

Ovarian granulosa cell tumor is a rare gynecologic malignancy with hormonal activity. Surgical excision is the standard treatment for this disease. Most patients present excellent short term prognosis, however, late relapse often occurs, even after many years. Viable treatments of advanced or relapsed granulosa cell tumor are still limited, and the optimal therapy method has not been established. Compared with chemotherapy and radiotherapy, hormonal therapy is a well-tolerated treatment which can be administrated over a long period of time without serious side effects, and the combined application of hormones may achieve a better outcome. Therefore, hormonal therapy has been suggested as a potential treatment option for patients with advanced or relapsed granulosa cell tumor, and to extend the tumor-free interval and attenuate the disease progression. Future researches should be focused on the identification of the hormonal therapy which may provide the greatest clinical benefit, comparing and analyzing the effects of different combined therapeutic regimens of hormone drugs, and on the synthesis of drugs highly activating estrogen receptor β expressed in the granulosa cell tumor cells.

Fluorescence enhancement in visible light: dielectric or noble metal?

A comprehensive comparison is conducted between a dielectric and plasmonic metal to evaluate their capability and applicability in fluorescence enhancement.

The response of meat ducks from 15 to 35 d of age to gossypol from cottonseed meal

The objective of this study was to investigate the responses of meat ducks of 15 to 35 d of age to free gossypol (FG) from cottonseed meal (CSM) and to establish the maximum limits of dietary FG concentration based on growth performance, blood parameters, and tissue residues of gossypol. Nine hundred 15-d-old ducks were randomly allocated to 5 treatments with 10 cages/treatment and 18 ducks/cage on the basis of BW. Five isonitrogenous and isocaloric experimental diets were formulated on a digestible amino acid basis to produce diets in which 0% (without FG), 25% (36 mg FG/kg), 50% (75 mg FG/kg), 75% (111 mg FG/kg), and 100% (153 mg FG/kg) of protein from soybean meal were replaced by that from CSM. Increasing dietary FG content, BW, and ADG decreased (linearly, P < 0.05, except for ADG of days 29 to 35), and F/G linearly increased (P < 0.05). At 35 d, blood hemoglobin, mean corpuscular hemoglobin, and mean corpuscular hemoglobin concentration linearly decreased (P < 0.05), while serum total protein, albumin, and globulin content linearly decreased (P < 0.05), and the residue of gossypol in liver, kidney, heart, breast, and leg muscle linearly increased (P < 0.001) with increases in dietary FG concentration. Ducks fed 36 mg FG/kg (5.83% CSM of diet) diet had a normal histological structure of liver, and muscle (breast and leg) had no residue of gossypol. The maximum limit of dietary FG concentration was estimated to range from a low of 36 mg/kg to maximize serum globulin concentration to a high of 124 mg/kg to minimize feed intake for 22 to 28d on the basis of a quadratic broken-line model.

Plasmonic coupled-cavity system for enhancement of surface plasmon localization in plasmonic detectors

A plasmonic coupled-cavity system, which consists of a quarter-wave coupler cavity, a resonant Fabry-Pérot detector nanocavity, and an off-resonant reflector cavity, is used to enhance the localization of surface plasmons in a plasmonic detector. The coupler cavity is designed based on transmission line theory and wavelength scaling rules in the optical regime, while the reflector cavity is derived from off-resonant resonator structures to attenuate transmission of plasmonic waves. We observed strong coupling of the cavities in simulation results, with an 86% improvement of surface plasmon localization achieved. The plasmonic coupled-cavity system may find useful applications in areas of nanoscale photodetectors, sensors, and an assortment of plasmonic-circuit devices.

Low Temperature Processing for Multilevel Interconnection and Packaging

The future high density multilevel interconnection and packaging requires that the combination of the insulator and conductor layers has a low RC value. Thermal stress and diffusion during processing are issues of great concern in the high density multilevel structures. The problem can be alleviated by a proper choice of materials and processes that do not require high temperature. In this paper we propose to use parylene and its derivatives (dielectric constant 2.3–2.6) as the possible interlayer dielectrics and Cu (bulk resistivity ∼1.7 μ Ω-cm) as the conductor. Parylene can be vapor-deposited and cured at room temperature. The metallization of Cu has been achieved at room temperature using the newly developed partially ionized beam deposition technique. This technique has been shown to grow high quality metal films with low resistivity at low substrate temperatures. The interaction between Cu and parylene, including adhesion and diffusion, is also discussed.

Carbon nanotube Schottky diode: an atomic perspective

The electron transport properties of semiconducting carbon nanotube (SCNT) Schottky diodes are investigated with atomic models using density functional theory and the non-equilibrium Green's function method. We model the SCNT Schottky diode as a SCNT embedded in the metal electrode, which resembles the experimental set-up. Our study reveals that the rectification behaviour of the diode is mainly due to the asymmetric electron transmission function distribution in the conduction and valence bands and can be improved by changing metal-SCNT contact geometries. The threshold voltage of the diode depends on the electron Schottky barrier height which can be tuned by altering the diameter of the SCNT. Contrary to the traditional perception, the metal-SCNT contact region exhibits better conductivity than the other parts of the diode.

Stochastic and deterministic models for agricultural production networks

An approach to modeling the impact of disturbances in an agricultural production network is presented. A stochastic model and its approximate deterministic model for averages over sample paths of the stochastic system are developed. Simulations, sensitivity and generalized sensitivity analyses are given. Finally, it is shown how diseases may be introduced into the network and corresponding simulations are discussed.

Activation of poly(ADP-ribose) polymerase contributes to development of doxorubicin-induced heart failure

Activation of the nuclear enzyme poly(ADP-ribose) polymerase (PARP) by oxidant-mediated DNA damage is an important pathway of cell dysfunction and tissue injury in conditions associated with oxidative stress. Increased oxidative stress is a major factor implicated in the cardiotoxicity of doxorubicin (DOX), a widely used antitumor anthracycline antibiotic. Thus, we hypothesized that the activation of PARP may contribute to the DOX-induced cardiotoxicity. Using a dual approach of PARP-1 suppression, by genetic deletion or pharmacological inhibition with the phenanthridinone PARP inhibitor PJ34, we now demonstrate the role of PARP in the development of cardiac dysfunction induced by DOX. PARP-1+/+ and PARP-1-/- mice received a single injection of DOX (25 mg/kg i.p). Five days after DOX administration, left ventricular performance was significantly depressed in PARP-1+/+ mice, but only to a smaller extent in PARP-1-/- ones. Similar experiments were conducted in BALB/c mice treated with PJ34 or vehicle. Treatment with a PJ34 significantly improved cardiac dysfunction and increased the survival of the animals. In addition PJ34 significantly reduced the DOX-induced increase in the serum lactate dehydrogenase and creatine kinase activities but not metalloproteinase activation in the heart. Thus, PARP activation contributes to the cardiotoxicity of DOX. PARP inhibitors may exert protective effects against the development of severe cardiac complications associated with the DOX treatment.

Partial protection by poly(ADP-ribose) polymerase inhibitors from nitroxyl-induced cytotoxity in thymocytes

Nitroxyl (NO(-)/HNO), has been proposed to be one of the NO(*)-derived cytotoxic species. Although the biological effect of nitroxyl is largely unknown, it has been reported to cause DNA breakage and cytotoxicity. We have therefore investigated whether NO(-)/HNO-induced DNA single-strand breakage activates the nuclear nick sensor enzyme poly(ADP-ribose) polymerase (PARP) and whether PARP activation affects the mode of NO(-)/HNO- induced cell death. NO(-)/HNO generated from Angeli's salt (AS, sodium trioxodinitrate) (0-300 microM) induced DNA single-strand breakage, PARP activation, and a concentration-dependent cytotoxicity in murine thymocytes. AS-induced cell death was also accompanied by decreased mitochondrial membrane potential and increased secondary superoxide production. The cytotoxicity of AS, as measured by propidium iodide uptake, was abolished by electron acceptors potassium ferricyanide, TEMPOL, the intracellular calcium chelator BAPTA-AM, and by PARP inhibitors 3-aminobenzamide (3-AB) and PJ-34. The cytoprotective effect of 3-AB was paralleled by increased output of AS-induced apoptotic parameters such as phosphatidylserine exposure, caspase activation, and DNA fragmentation. No significant increase in tyrosine nitration could be observed in AS-treated thymocytes as opposed to peroxynitrite-treated cells, indicating that tyrosine nitration is not likely to contribute to NO(-)/HNO-induced cytotoxicity. Our results demonstrate that NO(-)/HNO-induced PARP activation shifts the default apoptotic cell death toward necrosis in thymocytes. However, as total PARP inhibition resulted only in 30% cytoprotection, PARP-independent mechanisms dominate NO(-)/HNO-induced cytotoxicity in thymocytes.

Cooperative folding of the isolated alpha-helical domain of hen egg-white lysozyme

Proteins in the alpha-lactalbumin and c-type lysozyme family have been studied extensively as model systems in protein folding. Early formation of the alpha-helical domain is observed in both alpha-lactalbumin and c-type lysozyme; however, the details of the kinetic folding pathways are significantly different. The major folding intermediate of hen egg-white lysozyme has a cooperatively formed tertiary structure, whereas the intermediate of alpha-lactalbumin exhibits the characteristics of a molten globule. In this study, we have designed and constructed an isolated alpha-helical domain of hen egg-white lysozyme, called Lyso-alpha, as a model of the lysozyme folding intermediate that is stable at equilibrium. Disulfide-exchange studies show that under native conditions, the cysteine residues in Lyso-alpha prefer to form the same set of disulfide bonds as in the alpha-helical domain of full-length lysozyme. Under denaturing conditions, formation of the nearest-neighbor disulfide bonds is strongly preferred. In contrast to the isolated alpha-helical domain of alpha-lactalbumin, Lyso-alpha with two native disulfide bonds exhibits a well-defined tertiary structure, as indicated by cooperative thermal unfolding and a well-dispersed NMR spectrum. Thus, the determinants for formation of the cooperative side-chain interactions are located mainly in the alpha-helical domain. Our studies suggest that the difference in kinetic folding pathways between alpha-lactalbumin and lysozyme can be explained by the difference in packing density between secondary structural elements and support the hypothesis that the structured regions in a protein folding intermediate may correspond to regions that can fold independently.

[The clinical value of surgical-pathological staging for endometrial carcinoma]

OBJECTIVE

To explore the practical value of surgical-pathological staging for endometrial carcinoma.

METHODS

Ninety-six patients with endometrial carcinoma accepted primary surgical treatment from January 1995 to December 1999 were analyzed retrospectively in our hospital. The clinical and surgical pathologic staging of these patients were compared.

RESULTS

The total differences between clinical and surgical-pathologic staging were 44 cases (45.8%), in stage I 24.0%, stage II 76.9%, in stage III 2 of 5 cases. The metastasis rate of pelvic lymph nodes was 10.3%, in stage I 1 of 16 cases, stage II 14.7%. Fourteen patients (14.6%) with extrauterine pelvic metastasis were found, of which 2 of 19 cases in stage I b, 23.1% in stage II. 9.4% with ovarian metastasis, in stage I a 9.7%, stage II 10.3%. 7.9% with positive peritoneal cytology, in stage I 4.0%, stage II 10.3%. 5.2% with omentum metastasis. 2.1% with appendix metastasis. Clinical stages, depth of myometrial invasions, pathological grades and histological types were related to the extent of pelvic and abdominal cavity by univariate analysis (P < 0.01, 0.05). The first three factors were significantly correlated to dissemination by multivariate (P < 0.05).

CONCLUSIONS

The surgical-pathological staging is more accurate than the clinical staging, especial in stage II clinical stage depth of myoinvasion, patho-histological grades were closely related to the dissemination in pelvic-abdominal cavity. The surgical-pathological staging is able to assess prognosis objectively and guide therapy for endometrial carcinoma.

Peroxynitrite production, DNA breakage, and poly(ADP-ribose) polymerase activation in a mouse model of oxazolone-induced contact hypersensitivity

Peroxynitrite-induced poly(ADP-ribose) polymerase activation has been implicated in the pathogenesis of various inflammatory conditions. Here we have investigated whether peroxynitrite and poly(ADP-ribose) polymerase may play a role in the pathophysiology of the elicitation phase of contact hypersensitivity. We have detected nitrotyrosine, DNA breakage, and poly(ADP-ribose) polymerase activation in the epidermis of mice in an oxazolone-induced contact hypersensitivity model. As tyrosine nitration is mostly mediated by peroxynitrite, a nitric-oxide-derived cytotoxic oxidant capable of causing DNA breakage, we have applied peroxynitrite directly on mouse skin and showed poly(ADP-ribose) polymerase activation in keratinocytes and in some scattered dermal cells. We have also investigated the cellular effects of peroxynitrite in HaCaT cells, a human keratinocyte cell line. We found that peroxynitrite inhibited cell proliferation and at higher concentrations also caused cytotoxicity. Peroxynitrite activates poly(ADP-ribose) polymerase in HaCaT cells and poly(ADP-ribose) polymerase activation contributes to peroxynitrite-induced cytotoxicity, as indicated by the cytoprotective effect of the poly(ADP-ribose) polymerase inhibitor 3-aminobenzamide. The cytoprotective effect of 3-aminobenzamide cannot be attributed to inhibition of apoptosis, as apoptotic parameters (caspase activation and DNA fragmentation) were not reduced in the presence of 3-aminobenzamide in peroxynitrite-treated cells. Moreover, poly(ADP-ribose) polymerase inhibition by 3-aminobenzamide dose-dependently reduced interferon-induced intercellular adhesion molecule 1 expression as well as interleukin-1beta-induced interleukin-8 expression. Our results indicate that peroxynitrite and poly(ADP-ribose) polymerase regulate keratinocyte function and death in contact hypersensitivity.

Structure and dynamics of the alpha-lactalbumin molten globule: fluorescence studies using proteins containing a single tryptophan residue

The fluorescence properties of three variants of alpha-lactalbumin (alpha-LA) containing a single tryptophan residue were investigated under native, molten globule, and unfolded conditions. These proteins have levels of secondary structure and stability similar to those of the wild type. The fluorescence signal in the native state is dominated by that of W104, with the signal of W60 and W118 significantly quenched by the disulfide bonds in their vicinity. In the molten globule state, the magnitude of the fluorescence signal of W60 and W118 increases, due to the loss of rigid, specific side chain packing. In contrast, the magnitude of the signal of W104 decreases in the molten globule state, perhaps due to the protonation of H107 or quenching by D102 or K108. The solvent accessibilities of individual tryptophan residues were investigated by their fluorescence emission maximum and by acrylamide quenching studies. In the native state, the order of solvent accessibility is as follows: W118 > W60 > W104. This order changes to W60 > W104 > W118 in the molten globule state. Remarkably, the solvent accessibility of W118 in the alpha-LA molten globule is lower than that in the native state. The dynamic properties of the three tryptophan residues were examined by time-resolved fluorescence anisotropy decay studies. The overall rotation of the molecule can be observed in both the native and molten globule states. In the molten globule state, there is an increase in the extent of local backbone fluctuations with respect to the native state. However, the fluctuation is not sufficient to result in complete motional averaging. The three tryptophan residues in the native and molten globule states have different degrees of motional freedom, reflecting the folding pattern and dynamic heterogeneity of these states. Taken together, these studies provide new insight into the structure and dynamics of the alpha-LA molten globule, which serves as a prototype for partially folded proteins.

[The effect of tamoxifen of endometrium]

OBJECTIVE

To evaluate the effect of tamoxifen on the endometrium.

METHODS

Hysteroscopy and endometrial biopsies were performed in 26 patients with breast cancer receiving tamoxifen and having vaginal bleeding or endometrial thickness detected by ultrasound. In addition 78 women with postmenopausal bleeding without receiving tamoxifen underwent the same examination.

RESULTS

Thirteen (50.0%) patients receiving tamoxifen had endometrial or endocervical polyps, whereas 14 cases(17.9%) not receiving tamoxifen developed the polyps (P < 0.05). Nine (34.6%) patients receiving tamoxifen had thyperplasias, which was significantly higher than that of women not receiving tamoxifen (P < 0.05).

CONCLUSIONS

The incidence of endometria disease in the patient with breast cancer receiving tamoxifen was increased. These patients should be closely monitored by transvaginal sonography and hysteroscopy.