Probing the Electronic Structure and Chemical Bonding of Uranium Nitride Complexes of NU-XO (X = C, N, O).

Uranium(III) compounds are very reactive and exhibit a broad range of chemical-bonding tendencies owing to the spatially diffused valence orbitals of uranium. A systematic study on the geometries, electronic structures, and chemical bonding of NU-XO (X = C, N, O) is performed using relativistic quantum chemistry approaches. The NU-CO and NU-NO complexes have an end-on structure, that is, (NU) (η1-CO) and (NU) (η1-NO), whereas NU-OO adopts a side-on ((NU) (η2-O2)) structure. The electronic structure analysis shows that UN exhibits efficient activation reactivity to molecules, especially to NO and O2, because of the significant U 7s/5f → XO 2π* electron transfer. Thus, the oxidation state of U is +V with the dianion ligand NO2- and O22- in NU-NO and NU-OO, respectively. Instead, U retains its usual +III oxidation state in NU-CO with a neutral CO ligand. The significant stability of NU-XO (X = C, N, O) is determined by the covalent U-X bonding which contains both X → U σ-, π-donation from the X lone pair and U 5f → XO 2π* back-donation contributions. The significant back-donation to the antibonding X-O 2π* orbital results in the obvious weakening of the X-O bonding.

[Clinical observation of the immediate breast reconstruction following breast-conserving surgery for centrally located breast cancer].

OBJECTIVE: To investigate the clinical efficacy of the immediate breast reconstruction following breast-conserving surgery for centrally located breast cancer. METHODS: From January of 2006 through December of 2011, 30 women with centrally located breast cancer of stage I or II was treated by breast-conserving surgery removing or not removing the nipple-areola complex. All the patients received immediate breast reconstruction with adjacent gland tissue flap or latissimus dorsi myocutaneous flap. The breast shape and complication were observed. All the patients were followed up. RESULTS: The thirty women underwent the breast-conserving surgery successfully, in which 12 cases received immediate breast reconstruction with adjacent gland tissue flap and 18 cases received immediate breast reconstruction with latissimus dorsi myocutaneous flap. The superior rate of the aesthetic effect was 90% (27/30) according to JCRT in one week or six months after surgery. No recurrence and metastasis were observed after a median follow-up of 38 months ( range 4-72 months). CONCLUSION: The immediate breast reconstruction following breast-conserving surgery for centrally located breast cancer at early stage is satisfactory for the aesthetic result and clinical efficacy, and deserves further clinical application.

Triport periareolar thoracoscopic surgery versus right minithoracotomy for repairing atrial septal defect in adults.

OBJECTIVES: Our goal was to investigate the safety and feasibility of triport periareolar thoracoscopic surgery (TPTS) and its advantages in repairing adult atrial septal defect. METHODS: Between January 2017 and January 2020, a total of 121 consecutive adult patients underwent atrial septal defect closure in our institution. Of these, 30 patients had TPTS and 31 patients had a right minithoracotomy (RMT). Operational data and clinical outcomes were compared between the 2 groups. RESULTS: The total operation time, cardiopulmonary bypass time and aortic cross-clamp time in the TPTS group were slightly longer than those in the RMT group, but there were no differences between the 2 groups. Compared with the RMT group, the TPTS group showed a decrease in the volume of chest drainage in 24 h (98.6 ± 191.2 vs 222.6 ± 217.2 ml; P = 0.032) and a shorter postoperative hospital stay (6.5 ± 1.5 vs 8.0 ± 3.7 days; P = 0.042). The numeric rating scale on postoperative day 7 was significantly less in the TPTS group than in the RMT group (2.82 ± 1.14 vs 3.56 ± 1.42; P = 0.034). The patient satisfaction scale for the cosmetic results in the TPTS group was significantly higher than in the RMT group (4.68 ± 0.55 vs 4.22 ± 0.76; P = 0.012). No differences were found in postoperative complications. No in-hospital death or major adverse events occurred in the 2 groups. CONCLUSIONS: TPTS is safe and feasible for the closure of adult atrial septal defect. Compared with RMT, it has been associated with less pain and better cosmetic outcomes.

[Lesion localization and surgical resection for non-palpable breast cancer].

OBJECTIVE: To investigate the methods of lesion localization and surgical treatment for non-palpable breast cancer, presented with only small calcification lesion on the images. METHODS: From November 2003 to August 2007, 61 patients with non-palpable lesion were finally pathologically diagnosed as early breast cancer (T1-2N0M0), based on the small calcification lesions shown by full field digital mammography (FFDM) through molybdenum target, and the rich blood supply shown by type-B ultrasonic examination. Accurate lesion-localization prior to surgical resection was conducted, and sample re-examination by FFDM was done after resection. Patients with single lesion underwent breast-conserving surgery, precise excision with the aid of image-guided wire localization, and stage I breast reconstruction was performed simultaneously using wide-based gland-tissue flap. Patients with multiple lesions received modified radical mastectomy. RESULTS: Among the 50 patients treated with breast-conserving surgery, the accuracy of localization for lesions was 100% (50/50), and all lesions were excised completely with a negative margin proven by FFDM re-examination and pathological examination. The superior rate of mammaplasty was 86.0% (43/50) according to JCRT criteria, with a compliance difference of 1.5 cm. Modified radical mastectomy was performed in 11 patients. The follow-up period in this series was from 6 to 58 months with a mean follow-up time of 39 months. Distant metastases were detected in only one patient and local recurrence was not observed yet. CONCLUSION: Lesion localization by FFDM in patients with non-palpable breast cancer is accurate and practical. In patients with single lesion, breast-conserving resection followed by synchronous stage I breast reconstruction with wide-based gland-tissue flap is appropriate.

[Effects of chemotherapy on circulating angiogenic factor levels in patients with breast cancer].

OBJECTIVE: To study the changes in circulating VEGF and endostatin (ES) levels during chemotherapy for patients with breast cancer, and their correlation with efficacy of chemotherapy. METHODS: 40 breast cancer patients with metastases were included in this study. They received TAC/TEC, CAF/CEF, NP, CAP, CMF, TFP, TA or TC regime chemotherapy, respectively. Totally 120 serum samples were collected from the patients at three time points: before chemotherapy, the end of 1 and 5-6 chemotherapy cycles, and analyzed for VEGF and ES levels using ELISA. Tumor agiogenesis activity was evaluated by serum soluble vascular cell adhesion molecule (VCAM - 1) measured by ELISA as a surrogate marker. RESULTS: (1) Before chemotherapy, the median level of VEGF in patients with breast cancer was 496.6 pg/ml, 4.7 times higher than that of healthy controls (P <0.001). The median level of ES was 95.5 ng/ml, 18.3% lower than that of healthy controls (P = 0.183). VCAM-1 was 1077.1 ng/ml and higher than that of controls (P <0.001). The serum VEGF levels correlated with VCAM-1 levels, tumor staging and metastatic sites (P <0.05). (2) At the end of 1 cycle of chemotherapy, the serum VEGF level (median 524.8 pg/ml) was higher than the pretreatment values (P = 0.047), whereas the levels of ES and VCAM-1 were not significantly altered (110.5 ng/ml, P = 0.055; and 975.6 ng/ml, P = 0.27). (3) At the end of 5-6 cycles, the changes in VEGF correlated with the response to chemotherapy. Serum VEGF levels in 27 patients with chemotherapy-responsive and stable disease showed a significant decrease (median 287.4 pg/ml) , but not observed in 13 patients with progressive disease. VCAM-1 also showed a treatment-related change like VEGF. However, chemotherapy might only have a minor effect on ES, because there was no significant difference in the ES levels among 5-6 cycle patients, 1 cycle patients and healthy controls, and neither between therapy-responsive patients. CONCLUSION: Intensive chemotherapy for breast cancer results in a significant decrease of serum VEGF level, which might be an indicator of the controlled disease status, and following the treatment-induced response or stabilization, the tumor angiogenesis seems to change into an anti-angiogenesis direction.

The association of polymorphisms of CDT1 and GMNN gene with the risk of breast cancer in Chinese women: a case-control analysis.

OBJECTIVE: To investigate the association of polymorphisms of CDT1 and GMNN gene, two important genes participating in DNA replication, with the risk of sporadic breast cancer. METHODS: Using polymerase chain reaction-restriction fragment length polymorphism (PCR - RFLP) and the primer-introduced restriction analysis (PIRA)-PCR assay to genotype the CDT1 838G/A and GMNN 387C/A polymorphisms in a case-control study of 427 breast cancer cases and 477 cancer-free controls in a Chinese population. RESULTS: No significant association of the CDT1 838G/A and GMNN 387C/A polymorphisms with the risk of breast cancer was found (adjusted OR:1.16, 95% CI:0.88-1.54 for CDT1 GA+AA genotypes and adjusted OR:0.90, 95% CI:0.67-1.21 for GMNN CA+AA genotypes). However, in the stratified analyses, a significant association of CDT1 GA+AA genotypes with breast cancer risk among subjects with family history of cancer was found (adjusted OR:2.21, 95% CI:1.20-4.09). CONCLUSION: These findings suggest that the CDT1 838G/A and GMNN 387C/A polymorphisms may not play a major role in the etiology of breast cancer, but CDT1 variant may have a potential role only in genetically susceptible women.

Overexpression of microRNA-24 increases the sensitivity to paclitaxel in drug-resistant breast carcinoma cell lines via targeting ABCB9.

Paclitaxel has been widely used in the treatment of breast cancer. However, the development of drug resistance often increases the failure of chemotherapy. Growing evidence has reported the significant role of microRNAs (miRs) in drug resistance. The present study identified that miR-24 was significantly downregulated in paclitaxel-resistant (PR) breast cancer patients and in MCF-7/PR human breast carcinoma cells, and that overexpression of miR-24 could increase the effect of paclitaxel on drug-resistant breast carcinoma cells. Furthermore, miR-24 could directly bind to the 3'-untranslated region of ATP binding cassette B9 to downregulate its expression, thereby reducing drug transportation and improving the anti-tumor effect of paclitaxel on breast cancer cells. In vivo experiments also demonstrated that overexpression of miR-24 could increase the sensitivity of drug-resistant MCF-7 cells to paclitaxel. In conclusion, the present results suggested a novel function for miR-24 in reducing paclitaxel resistance in breast cancer, which may be of important clinical significance.

Coffee consumption and risk of breast cancer: an up-to-date meta-analysis.

OBJECTIVES: This updated meta-analysis was conducted to assess the association between coffee consumption and breast cancer risk. METHODS: We conducted a systematic search updated July 2012 to identify observational studies providing quantitative estimates for breast cancer risk in relation to coffee consumption. Pooled relative risks (RRs) with 95% confidence intervals (CIs) were calculated using a random-effects model, and generalized least square trend estimation was used to assess dose-response relationships. RESULTS: A total of 26 studies (16 cohort and 10 case-control studies) on coffee intake with 49497 breast cancer cases were included in the meta-analysis. The pooled RR showed a borderline significant influence of highest coffee consumption (RR = 0.96; 95% CI 0.93-1.00), low-to moderate coffee consumption (RR = 0.99; 95% CI 0.95-1.04), or an increment of 2 cups/day of coffee consumption (RR = 0.98; 95% CI 0.97-1.00) on the risk of breast cancer. In stratified analysis, a significant inverse association was observed in ER-negative subgroup. However, no significant association was noted in the others. CONCLUSIONS: Our findings suggest that increased coffee intake is not associated with a significantly reduced risk of breast cancer, but we observe an inverse association in ER-negative subgroup analysis. More large studies are needed to determine subgroups to obtain more valuable data on coffee drinking and breast cancer risk.

A modified tricuspid valve annuloplasty technique for functional tricuspid regurgitation.

BACKGROUND: Functional tricuspid regurgitation often occurs in patients with concomitant left sided, valve disease. Several types of tricuspid valve annuloplasty have been described, but there is no consensus on the management of functional tricuspid regurgitation. We report a modified annuloplasty technique and compare its efficacy with the conventional Kay technique. METHODS: A retrospective review was made of 60 patients who received tricuspid valve annuloplasty (group A, modified method; group B, Kay technique) and the early and midterm outcomes of modified method and Kay technique were compared. RESULTS: Three patients underwent ring annuloplasty using a semirigid Carpentier-Edwards ring due to failing suture annuloplasty. All patients were completely cured when they left the hospital. The follow-up time was (32 ± 7) months in group A and (30 ± 7) months in group B. After three years, tricuspid regurgitation decreased by more than two grades in 13 patients in group A and 11 in group B. The mean postoperative regurgitation grade in group A was lower than group B at 12, 24 and 36 months but not significantly. Three of 28 patients developed recurrent tricuspid regurgitation in group A and five of 26 patients in group B during the follow-up period (three deaths and three ring annuloplasties excluded). Freedom from recurrent tricuspid regurgitation in group A was higher than that group B at all follow-up points. Postoperative right atrium diameter, right ventricle endodiastolic dimension and tricuspid regurgitation area decreased obviously in both groups. The right ventricle endodiastolic dimension and tricuspid regurgitation area improved more significantly in group A than group B over three years of follow-up, CONCLUSIONS: The modified annuloplasty technique achieved the same outcomes as the conventional Kay annuloplasty over the first three years postoperation. As this modified technique is simple and less expensive, it is another option for correction of functional tricuspid regurgitation.

Circulating levels of angiogenic cytokines in advanced breast cancer patients with system chemotherapy and their potential value in monitoring disease course.

PURPOSE: The low-dose metronomic chemotherapy was reported to inhibit directly tumor angiogenesis or VEGF secretion. The study aimed to seek for this effect of system chemotherapy by observing the changes in serum levels of angiogenic cytokines during treatment and assessing their value in monitoring the advanced breast cancer. METHODS: In sixty-one patients with advanced breast cancer, serum levels of vascular endothelial growth factor (VEGF) and endostatin (ES) were compared at baseline (B0), after one cycle (B1), after 3 cycles (B3), and after 5-6 cycles (B5-6) of system chemotherapy using a quantitative ELISA. Data were correlated with treatment response and total survival. RESULTS: The response to chemotherapy did not correlate with serum VEGF level before therapy or after one cycle, but the changes in VEGF levels after 3 cycles and 5-6 cycles showed good association with clinical responses, i.e., the patients with disease control had a decreased VEGF value, whereas the progressive patients had an increased value. The Cox proportional hazard model revealed that a normalized VEGF level after therapy and an increase in VEGF level after 5-6 cycles were independent predictors for survival. CONCLUSIONS: System chemotherapy for advanced breast cancer lead to a significant decrease in serum VEGF level in patients with disease control, and this anti-VEGF efficacy may be mainly due to the reduction in tumor burden. Sequential measurement of serum VEGF could be useful for evaluating treatment efficacy and prognosis.