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Soil salinization is currently an important limiting factor on agriculture development in irrigation areas all over the world. Electrical conductivity (EC) is one of the main indicators which are used to determine whether the irrigation water will cause soil salinization. It is of important significance to study the temporal and spatial variation of groundwater EC for agricultural irrigation in irrigation districts. This study was conducted to examine the temporal stability and periodicity of groundwater EC in irrigation districts. To accomplish this, 51 observation wells were selected for analysis of groundwater EC in Luohuiqu irrigation district which was an important agricultural production base in Shaanxi Province, China. The 51 observation wells belonged to 3 different terraces which were Terrace 1, 2 and 3. The altitudes of the 3 terraces were >342-360, >360-369 and >370-388 m, respectively. The numbers of observation wells in Terrace 1, 2 and 3 were 26, 13 and 12, respectively. Water samples were collected from 2 m below the well water surface to measure the groundwater EC and temperature at each site. Well 36 (high EC) and 43 (low EC) were selected for long-term observation. A CTD-Diver (USA) groundwater level data logger was adopted for measuring and recording the groundwater EC, temperature and level. According to the long sequence monitoring results of groundwater EC for the 51 observation wells, relative difference analysis and non-parametric Spearman's rank correlation test were used to check for temporal stability of groundwater EC, while Morlet wavelet analysis was applied to study the periodic variation of groundwater EC and groundwater level of high and low salinity wells. The results indicated that the order of mean groundwater EC values of the 3 terraces at different time instants was Terrace 3 > Terrace 1 > Terrace 2. Significant difference existed among the mean groundwater EC values of the 3 terraces (P<0.01). The groundwater EC values of the 3 terraces at different time instants all indicated moderate spatial variability, with coefficient of variation (CV) values ranging from 44% to 75%. Based on the mean EC value of each observation well, 21 wells were slightly saline and 30 wells were moderately saline. The ranges of minimum and maximum value of groundwater EC were 0.08-0.14 and 0.50-1.00 S/m, respectively. The most of Spearman rank correlation coefficients for groundwater EC were close to 1 (P< 0.01), which indicated that the groundwater EC of the 3 terraces exhibited strong temporal stability. But the temporal stability of groundwater EC had little relationship with the terraces which the corresponding well sites belonged to. The representative locations of mean groundwater EC for Terrace 1, 2 and 3 were Well 40, 38 and 45, respectively. The representative location of mean groundwater EC for the entire study area was Well 2. Based on the Morlet wavelet analysis of the groundwater EC and water level of Well 36 (high EC) and 43 (low EC), both of the groundwater EC and water level showed periodic variations. The groundwater EC and water level indicated different vibration periods on different time scales for both Well 36 and 43. The change in groundwater EC on small time scales was mainly affected by lateral recharge sources. The groundwater EC and water level showed an obviously inverse phase on large time scales. In conclusion, the groundwater EC has strong temporal stability and periodicity in Luohuiqu irrigation district. The representative location with mean groundwater EC can be used to monitor the mean groundwater EC of the study area. Irrigation time should be fully considered in irrigation districts to avoid soil salinization. The representative location with mean groundwater EC can provide great guidance to determine the irrigation time quickly and accurately to reduce the risk of soil salinization. [ABSTRACT FROM AUTHOR]

Background and purpose: Currently, several studies have demonstrated that body mass index (BMI) is a prognostic factor in breast cancer. The study aimed to assess the association pattern of BMI with mortality risk among patients of different age groups. Methods: This retrospective cohort study included the clinical characteristics and survival status of 25 629 patients diagnosed with breast cancer and subsequently hospitalized in Fudan University Shanghai Cancer Center between January 1, 2008 and December 31, 2016. The association between BMI and prognosis of breast cancer patients in different age subgroups was analyzed using Cox proportional hazards regression model with restricted cubic splines adjusting the main prognostic factors. Results: BMI and age were both influencing factors of breast cancer prognosis, and there was a significant interaction (P = 0.011). The pattern of association between risk of death and BMI differed among different age groups. A "J-shaped" association between risk of death and BMI was observed in the patients younger than 35 years, with a BMI of 20.16 kg/m2 corresponding to the lowest risk of death. In the age group of 35-60 years, no significant change in the risk of death was observed in patients with BMI below 23 kg/m2, and the risk of death in patients with BMI above 23 kg/m2 increased with increasing BMI; A "U-shaped" association between risk of death and BMI was observed in the patients older than 60 years, with a BMI of 23.86 kg/m2 being the lowest. The risk of death was more sensitive to changes in BMI in patients aged less than 35 years than in those aged 35-60 years and those aged more than 60 years. Conclusion: BMI and age have a significant interaction in the prognosis of breast cancer when adjusted for potential confounding factors. The association pattern between the risk of death and BMI of patients in different age groups is different. For patients under 35 years old, the lowest risk of death corresponds to BMI at diagnosis of about 20 kg/m2, while for patients over 60 years old, the lowest risk of death corresponds to a BMI at diagnosis of about 24 kg/m2.

Objective: To evaluate the role of germline mutations of TP53 gene among a Chinese population with high risk for breast cancer., Methods: A total of 81 BRCA-negative breast cancer probands from cancer families were analyzed using targeted capture and next-generation sequencing. Candidate mutations were verified with Sanger sequencing. Co-segregation analyses were carried out to explore the likely pathogenicity of the mutation., Results: Of the 81 BRCA-negative patients, 3 exonic mutations in the TP53 gene were identified in 3 breast cancer patients. Of these, 2 mutations were previously reported and 1 was novel. One family with TP53 mutation has met the criteria for Li-Fraumeni syndrome (LFS) and accounted for 9.1% of all families who fulfilled the diagnostic criteria for LFS. Two of the carriers were diagnosed with breast cancer under the age of 30, and have accounted for 11.8% (2/17) of all very young (≤30 years) breast cancer patients in our study., Conclusion: The TP53 germline mutation is more common in Chinese population with a high risk for breast cancer than previously thought. TP53 gene mutation screening should be considered particularly for patients with a family history of LFS and very young age of onset.

Objective: To explore the current trends of breast reconstruction (BR) for breast cancer patients in China., Methods: A questionnaire was designed for this study, and it included questions on surgeon demographics, number of mastectomy and BR, type and timing of BR, reconstructive choices in the setting of preoperative or postoperative radiotherapy or chemotherapy, etc. All data were collected until December 2012. Questionnaires were sent to 52 members of the Committee of Breast Cancer Society by e-mail or mail., Results: By July 2013, 41 questionnaires had been returned. Among all, 5 were excluded for not performing BR. These 36 hospitals covered 22 provinces and municipalities in China. A total of 538 surgeons working in the general surgery or oncological surgery department, but only 123 (22.9%) were qualified to perform BR. In 2012, except for 4 missing data, 24, 763 mastectomies were performed in 32 hospitals; among them, 1120 (4.5%) received BR. According to these 36 respondents, 32 (88.9%) performed prosthetic (1, 843 cases in all) while 4 (11.1%) performed prosthetic BR with acellular dermal matrix (17 cases in all) from the time of their first BR operation to the end of 2012. During the same period, 965 latissimus dorsi myocutaneous flaps with implant were performed in 23 (63.9%) hospitals while 738 latissimus dorsi myocutaneous flaps without implant were performed in 32 (88.9%) hospitals. At the same time, 366 pedicled transverse rectus abdominis myocutaneous flap BRs were performed in 28 (77.8%) hospitals, while 155 abdominal free flap BRs were carried out in 9 (25.0%) hospitals. The overall complication rate was 18.2%. Postoperative radiotherapy had some effect on influencing the esthetic outcomes of BR, so the autologous BR was recommended, but the timing remained controversial. Regarding chemotherapy, most respondents concluded that it had no effect or only a mild effect. The overall cosmetic outcomes of the reconstructed breasts satisfied the majority of physicians and patients., Conclusions: With more attention paid to the quality of life after mastectomy, more and more BRs are needed, but the ratio is still low in China. To improve this situation, more efforts are needed, including the improvement of the intrahospital framework of multi-disciplinary service, the training for doctors and the educational program for patients, etc.

Objective: To evaluate the feasibility of lymphoscintigraphy in sentinel lymph node biopsy of breast cancer., Method: Lymphoscintigraphy was performed after peritumoral or subdermal injection of radioactive colloid. Then, sentinel lymph node (SLN) biopsy guided by gamma detector probe was performed. Factors correlated with identification-detection rate were assessed., Results: Lymphatic drainage was present in preoperative lymphoscintigraphy in 88(93%) out of 95 patients, with 39 (44.3%) positive for lymphatic drainage other than in the axilla. A total of 91 (95.8%) patients had their SLN identified in the intraoperative procedure. The quality of lymphoscintigraphic image was closely related to SLN identification-detection rate in the intraoperative procedure (P = 0.025)., Conclusion: Sentinel lymph node outside the axilla can be detected by lymphoscintigraphy. The combination of lymphoscintigraphy and gamma detector probe for sentinel lymph node biopsy of breast cancer not only is acceptable but promising.

Objective: To evaluate the accuracy of sentinel lymph node biopsy (SLNB) to predict the axillary lymph node status in breast cancer patients and its clinical significance., Methods: Seventy patients with clinical TNM status T(1 - 2)N(0)M(0) underwent sentinel lymph node biopsy using Tc-99m sulfur colloid radiotracer and gamma probe, which was followed by standard axillary dissection. SLNB was compared with standard axillary dissection for its ability to reflect the final pathological status of the axillary nodes. The SLNs that were tumor negative in conventional HE staining were further evaluated using immunohistochemical stains for CK8, CK19 and KP-1 antibodies., Results: The sentinel lymph node (SLN) was successfully identified in 67 (95.7%) out of 70 patients. The number of sentinel nodes harvested ranged from 1 to 5 (average 1.6). The nonsentinel nodes ranged from 5 to 20 (average 12.3). Of the 67 patients, 29 (43.3%) had histologically positive axillary lymph nodes. SLN was positive in 24 patients with metastasis (35.8%), and in 7 patients without metastasis (10.4%). In 5 patients, SLN was negative for tumor with positive nodes. The accuracy of sentinel lymph node biopsy to predict the axillary lymph node status was 92.5% and the false negative rate was 7.5%. For tumors with diameter less than or equal to 2 cm, the accuracy was 100%. 65 SLNs that were negative for HE stain were also non-reactive to immunostain for CK8 and CK19 antibody., Conclusions: SLNB can accurately predict the axillary lymph node status in most of breast cancer patients. The accuracy is about 100% in patients with T(1) lesions. Immunohistochemical staining at the same level of HE stain can not increase the detection of lymph node micrometastasis.