Lnc-AC145676.2.1-6-3 can influence STX3-induced abnormal autophagy by sponging hsa-miR-1292-3p in intestinal aGVHD.

OBJECTIVE: Intestinal acute graft-versus-host disease (aGVHD) is a serious complication of allogeneic hematopoietic stem cell transplantation (allo-HSCT). Abnormal autophagy levels in intestinal aGVHD have been confirmed in many studies. LncRNAs exert coregulatory functions and participate in a variety of intracellular regulatory processes. In this study, we investigated how lnc-AC145676.2.1-6-3 regulates dysregulated STX3-related autophagy in aGVHD. MATERIALS AND METHODS: First, we established a mouse model of aGVHD by transplanting a mononuclear cell suspension from Balb/c donor mice treated with 60Co X-rays into CB6F1 recipient mice. STX3-related indicators were analyzed by Western blotting (WB) and immunohistochemistry which confirmed that STX3 plays an important role in dysregulating autophagy in intestinal aGVHD. TNF-αinduced Caco-2 cells, which is an in vitro model of intestinal barrier dysfunction, were established to verify the effect of STX3. The direct interaction between the partners of lnc-AC145676.2.1-6-3-mediated hsa-miR-1292-3p and STX3 axis was evaluated by the Dual-Luciferase activity assay. We performed PCR, WB, and immunofluorescence in Caco-2 cells to determine whether the abnormal autophagy levels were influenced by lnc-AC145676.2.1-6-3. RESULTS: The results showed that lnc-AC145676.2.1-6-3 could significantly suppress the number of autophagic vacuoles, the LC3-II/I ratio, and beclin1 levels by increasing STX3 levels. CONCLUSIONS: Lnc-AC145676.2.1-6-3 may play an important role in intestinal aGVHD by targeting STX3.

[CART therapy followed by allo-HSCT for patients with B-cell acute lymphoblastic leukemia relapsing after the first hematopoietic stem cell transplantation].

Objective: To study the clinical efficacy of chimeric antigen receptor T-cell (CART) treatment followed by a second allogeneic hematopoietic stem cell transplantation (allo-HSCT) in patients with B-cell acute lymphoblastic leukemia (ALL) who relapsed following the first HSCT. Methods: Retrospective analysis of the clinical characteristics and prognosis of 41 patients with B-cell ALL who received a second allo-HSCT from October 2015 to June 2020 in Hebei Yanda Lu Daopei Hospital. After the first HSCT, all patients received CD19-CART, or CD22-CART treatment following a relapse of bone marrow morphology or extramedullary leukemia. Results: A total of 41 patients (male, 21; female, 20) were included in this study. The median age at the second HSCT was 16 (3-46) years. There were 31 cases of bone marrow recurrence (75.6%) , 5 cases of extramedullary recurrence (12.2%) , and 5 cases of bone marrow and extramedullary recurrences (12.2%) . After relapse, 35 patients (85.4%) received CD19-CART treatment, 2 patients received CD22-CART treatment (4.9%) , and 4 patients received CD19-CART and CD22-CART treatments (9.8%) . The expected 3-year overall survival (OS) , leukemia-free survival, cumulative relapse incidence, and non-relapse mortality (NRM) of patients after the second HSCT were 48.9% (95%CI 23.0%-70.6%) , 41.8% (95%CI 17.3%-64.9%) , 8.8% (95%CI 2.9%-26.4%) , and 51.1% (95%CI 31.2%-83.6%) , respectively. The 1-year OS of patients who relapsed ≤6 months and >6 months after the first HSCT were 45.0% (95%CI 12.7%-73.5%) and 75.0% (95%CI 51.4% -88.8%) (P=0.017) , respectively. Conclusion: CART bridging in the second HSCT enables some B-cell ALL patients who relapsed after the first HSCT to achieve long-term survival. However, because of the high NRM, further modifications could help improve the outcome.

[Comparison of the clinical outcomes of haploidentical and matched-sibling donor stem cell transplantation for T cell acute lymphoblastic leukemia in complete remission].

Objective: To compare the efficacy of haplotype hematopoietic stem cell transplantation (HIDT) and sibling matched hematopoietic stem cell transplantation (MSDT) in the treatment of complete remission (CR) acute T-lymphoblastic leukemia (T-ALL) . Methods: We retrospectively analyzed the clinical characteristics and outcomes of 98 patients who underwent HSCT in Hebei Yanda Ludaopei hospital with HID (n=81) or ISD (n=17) between May 2012 and May 2016. Results: The incidence of grades 2-4 and 3-4 acute-versus-host disease 100 days after HSCT were 51.9% (95% Confidence interval [CI] 42.0%-64.0%) vs 29.4% (95% CI 14.1%-61.4%) (P=0.072) and 9.8% (95% CI 5.1%-19.1%) vs 11.8% (95% CI 3.2%-43.3%) (P=1.000) for HIDT and MSDT. The 100-day cumulative incidences of CMV and EBV viremia were 53.1% (95% CI 43.3%-65.2%) vs 29.4% (95% CI 14.1%-61.4%) (P=0.115) and 35.8% (95% CI 26.8%-47.9%) vs11.8% (95% CI 3.2%-43.3%) (P=0.048) . The 5-year overall survival, leukemia-free survival, cumulative incidences of relapse, and no-relapse mortality were 60.5% (95% CI 5.4%-49.0%) vs 68.8% (95% CI 11.8%-40.0%) (P=0.315) , 58.0% (95% CI 5.5%-46.5%) vs 68.8% (95% CI 11.8%-40.0%) (P=0.258) , 16.1% (95% CI 9.8%-26.4%) vs 11.8% (95% CI 3.2%-43.3%) (P=0.643) , 25.9% (95% CI 17.9%-37.5%) vs 19.4% (95% CI 6.9%-54.4%) (P=0.386) for HIDT and MSDT, respectively. Conclusion: HID could be a valid alternative donor for patients with T-ALL in CR lacking an identical donor.

[The effect of TP53 mutations on the clinical outcomes of Ph-negative B-acute lymphoblastic leukemia following allogeneic hematopoietic stem cell transplantation].

Objective: To evaluate the association of TP53 mutations with the clinical outcomes of Ph-negative B-ALL following allogeneic hematopoietic stem cell transplantation (allo-HSCT) . Methods: Total 300 patients with Ph-negative B-ALL who underwent allo-HSCT at the Hebei Yanda Ludaopei Hospital from May 2012 to May 2017 were retrospectively analyzed; their clinical characteristics, TP53 gene mutation type, and association between TP53 mutations and transplantation outcomes, including leukemia-free survival (LFS) , overall survival (OS) , non-relapse mortality (NRM) , relapse, and GVHD, were evaluated. Results: Total 23 patients had TP53 mutations; all the TP53 mutations affected P53'DNA-binding domain. The 5-year-LFS, OS, and RI were 34.8% and 62.3% (P=0.001) , 41.9% and 65.1% (P=0.020) , and 47.8% and 14.8% (P=0.000) , respectively, for TP53 mutations and wild-type TP53 patients. However, there were no significant differences in NRM and GVHD. Multivariate analysis showed that TP53 mutations remained adverse prognostic factors for LFS, OS, and RI after allo-HSCT. Conclusion: Some patients with TP53 mutations can achieve long-term survival with allo-HSCT. TP53 mutations are adverse prognostic factors for Ph-negative B-ALL patients who undergo allo-HSCT.

[Threshold effects of body mass index on the bone mineral density of Chinese rural women in fluorosis area].

To explore the threshold effect of body mass index (BMI) on bone mineral density (BMD) in Chinese women living in the fluorosis area, we conducted a cross-sectional study and recruited 722 women in rural areas in Henan Province, China. After detection and analyses, we found that compared with the normal BMI group, the risk of osteoporosis in the overweight and obese groups were reduced by 32% and 69%, respectively. Threshold effect analysis showed that BMD was positively correlated with BMI when BMI was 16.8-31.2 kg/m2; while when BMI was greater than 31.2 kg/m2, the correlation reached saturation. The correlation observed between low-to-moderate fluoride exposure and BMD in rural women was not significant.

[Prognostic analysis of allogeneic hematopoietic stem cell transplantation for Philadelphia chromosome-positive acute lymphoblastic leukemia in complete remission in the era of tyrosine kinase inhibitors].

Objective: To study the clinical results and prognostic factors for allo-HSCT of Philadelphia chromosome-positive (Ph(+)) acute lymphoblastic leukemia (ALL) in complete remission (CR) in the era of tyrosine kinase inhibitors (TKI) . Methods: We performed a retrospective analysis of the clinical characteristics of 116 patients with Ph(+)ALL who underwent allo-HSCT while in CR. Results: The study population included 72 men and 44 women. The median patient age was 20 years (4-64 years) . The patients received sibling-identical donor (n=21) , haplo (n=77) , and unrelated donor (n=18) HSCT. The overall survival (OS) rate at 5 years was 73.2% (95% CI 63.8% -80.5% ) . In particular, the 5-year OS can reach 87.5% when the time from diagnosis to transplant is <180 days. The 5-years DFS was 61.4% (95% CI 51.8% -69.7% ) , the 5-year molecular and morphology cumulative relapse incidence was 18.5% (95% CI 12.6% -27.3% ) , and the 5-year TRM was 19.9% (95% CI 13.8% -28.7% ) . A multivariate analysis showed that an age range of 15-39 years (HR=2.730, P=0.044) , time from diagnosis to HSCT ≥ 180 days (HR=4.534, P=0.010) , and Ⅲ-Ⅳgrade aGVHD (HR=7.558, P=0.000) were significantly associated with an inferior overall survival. Limited cGVHD subgroup had better OS (HR=0.300, P=0.034) . Sex, WBC count at diagnosis, type of BCR-ABL fusion genes, somatic gene mutations, CR(1) or >CR(1), MRD negative or positive, conditioning regimen based on TBI or Bu, conditioning intensity, donor source, GVHD prophylactic proposal using cyclosporine or tacrolimus, presence/absence of CMV viremia, and presence/absence of EBV viremia were not significantly different in terms of the OS and DFS. Conclusion: Factors influencing the overall survival of Ph(+) ALL patients who underwent allo-HSCT in CR in the TKI era include age, time form diagnosis to HSCT, and aGVHD severity.

[A new exploration and consideration of Type A fracture of distal femur based on finite element biomechanical analysis].

Objective: To investigate the changes of internal fixation stress under different angles of interior fracture line and different screw placement modes in the case of A-type distal femoral fracture. Methods: A 24-year-old healthy male volunteer was recruited to collect the right femur data. CATIA V5R21 software produced a 10 mm fracture gap at the external side of the femur 6.5 cm proximal to the joint line and different angle fracture lines were generated on the internal of the femur at the same height. Based on the actual measured dimensions, the three-dimensional (3D) model of the locking plate and screw was reconstructed using CATIA V5R21 software, ignoring the screw surface threads and then the assembly of the internal fixation of the titanium plate, screws and femur was done. All models were meshed using Hypermesh 13.0 software. The assembled 3D model was input into ABAQUS 6.14 to generate a finite element model. Preliminary finite element biomechanical analysis was performed using the four medial fracture line angles and the stress distribution of the internal fixation under the three screw placement modes, and then the analysis was continued after the optimal screw placement method was re-determined. Results: Under an axial loading of 700 N, with the increase of the angle of the fracture line, the stress of the lateral internal fixation gradually increased, and the displacement of the proximal end of the fracture gradually increased. The sequential screw placement method was superior to the leaping screw placement method. The placement of the first screw at the proximal end of the fracture was critical to the distribution of the internal fixation stress. Conclusions: The operation plan of the type A of distal femoral fracture needs to be confirmed according to the internal and external fracture's condition. When the fracture line is at a excessive positive angle or a negative angle, a simple lateral fixation may not provide a stable fracture fixation so that other fixation methods are needed.

Short-term effect of metronomic chemotherapy of low-dose Tegafur on patients with primary hepatic carcinoma after radiofrequency ablation.

OBJECTIVE: To investigate the therapeutic effect of metronomic chemotherapy with low-dose Tegafur on patients with primary hepatic carcinoma (PHC) after radiofrequency ablation (RFA). PATIENTS AND METHODS: PHC patients who underwent RFA were assigned to RFA + Tegafur group and RFA group, respectively. Patients in RFA + Tegafur group received metronomic chemotherapy with low-dose Tegafur after RFA. PHC patients in RFA group only received radiofrequency ablation. Therapeutic efficacy of the two groups was prospectively analyzed within 18 months after RFA. Disease control rate (DCR) and progression-free survival (PFS) in both groups were evaluated. RESULTS: Follow-up data showed that DCR in RFA + Tegafur group and RFA group at 9 months after RFA was 93.3% and 73.4%, respectively (p=0.038). Within the 18-month follow-up, median PFS in RFA + Tegafur group and RFA group was 16.25 months and 12.25 months, respectively (p<0.001). One-year PFS in RFA group was 53.3%, which was remarkably lower than that of RFA + Tegafur group (83.3%, p=0.012). Moreover, the prevalence of major complications in the present study was 13.3%. No treatment-related death occurred in both groups. CONCLUSIONS: Metronomic chemotherapy with low-dose Tegafur after RFA can slow down tumor progression and prolong the progression-free survival of PHC patients.

TGF-ß1 promotes human hepatic carcinoma HepG2 cells invasion by upregulating autophagy.

OBJECTIVE: To study the role of TGF-ß1 in autophagy and invasion ability of human hepatic carcinoma HepG2 cells. MATERIALS AND METHODS: Cultured HepG2 cells were treated with different concentrations of TGF-ß1 for 24 h. The protein expression levels of autophagy relative marker LC3 and Beclin1 were detected by Western blot. The effect of TGF-ß1 on invasion ability of HepG2 cells was detected with transwell method. RESULTS: The results demonstrated that TGF-ß1 was able to activate autophagy of HepG2 cells in a dose-dependent manner. Autophagy inhibitor 3-methyladenine (3-MA) could reverse TGF-ß1 induced autophagy process. Also, TGF-ß1 significantly promotes the invasion ability of HepG2 cells; however, this process could effectively reverse by autophagy inhibitor 3-MA. CONCLUSIONS: TGF-ß1 enhances HepG2 cells invasion by upregulating autophagy.

[Comparison of three different types of donor hematopoietic stem cell transplantation for intermediate and high-risk myelodysplastic syndrome].

Objective: To investigate three different types of donor hematopoietic stem cell transplantation (HSCT) for intermediate and high-risk myelodysplastic syndrome (MDS) . Methods: Between August 2001 and May 2015, 167 consecutive patients with MDS in intermediate and high-risk who underwent allogeneic HSCT were analyzed retrospectively. Results: With the median follow up of 60 (12-177) months, The total 5-year DFS was 67.8% (95%CI 60.0%-75.6%) . Among three different types of donor, 5-year DFS rates were 68.0% (95%CI 54.1%-81.9%) in MSD-HSCT vs 77.4% (95%CI 62.1%-92.7%) in MUD-HSCT vs 64.0% (95% CI 52.4%-75.6%) in Haplo-HSCT (P=0.632) , respectively. Univariate analysis showed that median disease course before HSCT was the influencing factor of DFS (P=0.018) . Five-year relapse and TRM had no correlation with the above-mentioned factor. Conclusions: Haplo-HSCT for intermediate and high-risk MDS achieved similar effect produced by MUD or MSD, Haplo-HSCT could be used as an important alternative donor. allo-HSCT must be performed on intermediate and high-risk MDS patients as early as possible after diagnosis.

[Effect of minimal residual disease monitoring by multiparameter flow cytometry pre-conditioning on prognosis of acute myeloid leukemia after allogeneic hematopoietic stem cell transplantation].

Objective: To investigate the effect of minimal residual disease (MRD) monitoring by multiparameter flow cytometry (MFC) pre-conditioning on prognosis of acute myeloid leukemia in first complete remission (CR(1)-AML) after allogeneic hematopoietic stem cell transplantation (allo-HSCT) , and to explore the value of MRD monitoring by MFC in the prognosis evaluation on allo-HSCT in CR(1)-AML. Methods: Between April 2012 and March 2015, consecutive 186 patients with CR(1)-AML who underwent allo-HSCT were analyzed retrospectively. MRD in BM before conditioning was detected by eight-color MFC. Any level of residual disease was considered to be MRD positive. Results: ①Of 186 patients, MRD was negative in 151 patients, positive in 35 patients (<1% in 25 patients and 1% to 3% in 10 patients) . ② With the median follow up of 18 (5-41) months, two-year DFS was 80.0% (95%CI 68.5%-92.3%) . Univariate analysis showed that MRD positive patients had lower DFS[62.9% (95%CI 50.6%-75.2%) vs 88.9% (95%CI 76.6%-100.0%) , P<0.001], higher relapse[11.4% (95%CI 4.1%-29.0%) vs 3.3% (95% CI 0.6%-20.9%) , P=0.003] and higher NRM [25.7% (95% CI 8.1%-43.3%) vs 7.9% (95% CI 1.3%-26.5%) , P=0.001] after HSCT compared with that of MRD negative patients. Secondary AML showed lower DFS than primary AML [60.0% (95% CI 42.4%-76.6%) vs 86.0% (95% CI 68.4%-100.0%) , P=0.004]. ③Multivariate analysis indicated that MRD positive pre-HSCT was the independent risk factor on DFS [HR=4.565 (95%CI 2.918-9.482) , P<0.001], relapse [HR=5.854 (95%CI 1.538-22.288) , P=0.010] and NRM [HR=3.379 (95%CI 1.361-8.391) , P=0.009] after allo-HSCT in CR(1)-AML. Conclusion: MRD positive pre-conditioning was the only negative impact factor for patients with CR(1)-AML after allo-HSCT. MRD by MFC can be used to assess the prognosis of CR(1)-AML after allo-HSCT.

[Effect of NCCN (2015) risk stratification on prognosis of patients with acute myeloid leukemia after allogeneic hematopoietic stem cell transplantation].

Objective: To analyze the effect of NCCN (2015) risk stratification on prognosis of patients with acute myeloid leukemia (AML) after allogeneic hematopoietic stem cell transplantation (allo-HSCT) . Methods: Retrospective analysis of 258 patients with AML in CR (186 cases in CR(1), 72 cases in CR(2)) who underwent allogeneic HSCT in our hospital between April 2012 and March 2015 according to NCCN (2015) risk stratification. Of them, 63 cases were classified as low risk, 112 cases intermediate risk and 83 cases high risk. Results: ①With the median follow up of 18 (5-41) months, two-year disease free surviva (DFS) in 258 patients was 78.0% (95% CI 60.4%-96.6%) . Two-year DFS in AML after transplantation was 78.6% (95% CI 61.0%-96.2%) in low risk, 76.0% (95% CI 84.0%-93.6%) in intermediate risk and 80.3% (95% CI 62.7%-97.9%) (P=0.886) in high risk groups respectively. ②Univariate analysis showed that DFS has no significant difference in patient age, the median disease course before HSCT, the WBC number at the beginning of the disease, blood routine and chromosomes examination before transplantation, extramedullary disease before transplantation, disease status before transplantation, conditioning regimen, donor type, donor and recipient sex, recipient blood type, transfused MNC number, transfused CD34(+) cell number and transfused CD3(+) cell number. DFS was significant lower in primary AML than that in secondary AML (P=0.006) and also lower in MRD positive than that in MRD negative (P=0.003) . The accumulative relapse was significant higher in CR(2) compared to that in CR(1) (P=0.046) . Accumulative non-relapse mortality (NRM) was significanlyt higher in secondary AML compared to that in primary AML (P=0.004) and also higher in MRD positive compared to that in MRD negative (P=0.010) . ③Multivariate analysis showed that MRD positive was the only significant factor in DFS and NRM. Conclusion: Allo-HSCT treatment of AML CR patients could achieve a high efficacy, which is similar between CR(1) and CR(2) patients. There is no significant correlation between NCCN (2015) risk stratification and the prognosis of AML patients with allo-HSCT treatment. Pre-conditioning MRD status monitored by multiparameter flow cytometry was the only impact factor on DFS and NRM in allo-HSCT for CR-AML patients.

Risk Factors for Death of Elderly Patients with Acute Obstructive Suppurative Cholangitis.

OBJECTIVE: To identify the risk factors for death of elderly patients with acute obstructive suppurative cholangitis (AOSC). METHODS: Three hundred and forty-eight AOSC patients > 60 years of age were retrospectively analysed in the First People's Hospital of Jining from June 2005 to June 2013. The patients were treated with endoscopic retrograde cholangiopancreatography (ERCP) immediately after AOSC was diagnosed to clear the stones and drain, and surgical procedures were then performed in the patients in whom ERCP failed. The risk factors were identified with univariate and multivariate analysis. RESULTS: Among the 348 AOSC patients, 27 patients died after treatment. Two hundred and forty-nine patients were treated with ERCP, and 11 patients died; 99 patients were treated with ERCP plus surgery, and 16 patients died. Two hundred and thirty-two patients were treated within 24 hours after they were admitted to the hospital, and 10 patients died; 116 patients were treated beyond 24 hours, and 17 patients died. According to the results of the univariate and multivariate analysis, shock, ERCP plus surgery, advanced age, low platelet count, the presence of co-morbidities, door to treatment time > 24 hours, hypoproteinaemia, and hyperbilirubinaemia were the independent risk factors for death of elderly patients with AOSC. CONCLUSION: The strategies of dealing with these risk factors should be researched to reduce mortality of elderly patients with AOSC.

Cardiovascular research is thriving in China.

Cardiovascular disease has become the leading cause of death and constitutes a serious public health issue in China. Faced with the burgeoning epidemic of cardiovascular disease and the huge burden and economic losses it causes, the Chinese government has attached the utmost importance to cardiovascular research, increasing funding to support basic and clinical studies, integrating resources and recruiting outstanding talent from overseas. The continued and growing support from the government has yielded substantial changes in terms of new discoveries, scientific publications and drug research and development within the last decade. In spite of the advances in cardiovascular research, China still faces significant challenges ahead in encouraging innovation, developing the prevention-oriented health policies and strengthening international collaboration.

Innovations in the assessment of transplant center performance: implications for quality improvement.

Continuous quality improvement efforts have become a central focus of leading health care organizations. The transplant community has been a pioneer in periodic review of clinical outcomes to ensure the optimal use of limited donor organs. Through data collected from the Organ Procurement and Transplantation Network (OPTN) and analyzed by the Scientific Registry of Transplant Recipients (SRTR), transplantation professionals have intermittent access to specific, accurate and clinically relevant data that provides information to improve transplantation. Statistical process control techniques, including cumulative sum charts (CUSUM), are designed to provide continuous, real-time assessment of clinical outcomes. Through the use of currently collected data, CUSUMs can be constructed that provide risk-adjusted program-specific data to inform quality improvement programs. When retrospectively compared to currently available data reporting, the CUSUM method was found to detect clinically significant changes in center performance more rapidly, which has the potential to inform center leadership and enhance quality improvement efforts.

Kinetics of the endocytotic pathway of Low Density Lipoprotein (LDL) in human endothelial cells line under shear stress: an in vitro confocal microscopy study.

We studied the effect of mechanical forces (shear stress) on the kinetics of internalization of native LDL and ox-LDL in endothelial cell line ECV304. This study was performed by using Confocal microscopy and FRET with two carbocyanine dyes, 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate (DiO) as the donor and 3,3'-dioctadecyloxacarbocyanine perchlorate (DiI) as the receptor. The cells were incubated with a culture medium containing either 10 microg/ml DiI-LDL or DiO-LDL in static conditions or subjected to a laminar flow under a Confocal Laser Scanning Microscope (SP2 Leica, Germany). The results showed: (1) the possibility to evaluate the kinetics of LDL endocytosis in living cells, (2) shear stress in comparison with control group more effectively enhanced LDL uptake, (3) ox-LDL (>50 microg/ml) >4 hours incubation was found to affect the cells as reflected by their detachment at low shear stress.

Role of Ca2+ in the effects of shear stress and TNF-alpha on caveolin-1 expression.

The aim of this work was to study the influences of Ca2+ (medium free calcium, with BAPTA, with 100 mM Ca2+, 100 mM Ca2++10 microM ionomycin) on the expression of caveolin-1 (structural protein of caveolae) of endothelial cells (ECs) submitted to mechanical forces (shear stress) or biochemical stimulation (TNF-alpha). We found that shear stress enhanced the caveolin-1 expression. Simultaneously, the caveolin-1 expression is dependant on [Ca2+]i: [Ca2+]free medium+100 microM BAPTA<[Ca2+]free medium<[Ca2+]100 mM<[Ca2+]100 mM+10 microM ionomycin. In contrast, TNF-alpha induced a decrease of caveolin-1 in the cells, whatever the [Ca2+]i. These results suggest that there could be a synergistic effect between shear stress and Ca2+ on caveolin-1 expression but an inflammatory stimulation (TNF-alpha) induces a down regulation of caveolin-1 expression.

Optimum nitrogen use and reduced nitrogen loss for production of rice and wheat in the Yangtse Delta region.

A long-term field and lysimeter experiment under different amount of fertilizer-N application was conducted to explore the optimal N application rates for a high productive rice-wheat system and less N leaching loss in the Yangtse Delta region. In this region excessive applications of N fertilizer for the rice-wheat production has resulted in reduced N recovery rates and environment pollution. Initial results of the field experiments showed that the optimal N application rate increased with the yield. On the two major paddy soils (Hydromorphic paddy soil and Gleyed paddy soil) of the region, the optimal N application rate was 225-270 kg N hm(-2) for rice and 180-225 kg N hm(-2) for wheat, separately. This has resulted in the highest number of effective ears and Spikelets per unit area, and hence high yield. Nitrogen leaching in the form of NO(3-)-N occurs mainly in the wheat-growing season and in the ponding and seedling periods of the paddy field. Its concentration in the leachate increased with the N application rate in the lysimeter experiment. When the application rate reached 225 kg N hm(-2), the concentration rose to 5.4-21.3 mgN l(-1) in the leachate during the wheat-growing season. About 60% of the leachate samples determined contained NO(3-)-N beyond the criterion (NO(3-)-N 10 mg l(-1)) for N pollution. In the field experiment, when the N application rate was in the range of 270-315 kg hm(-2), the NO(3-)-N concentration in the leachate during the wheat-growing season ranged from 1.9 to 11.0 mg l(-1). About 20% of the leachate samples reached close to, and 10% exceeded, the criterion for N pollution. Long-term accumulation of NO(3-)-N from leaching will no doubt constitute a potential risk of N contamination of the groundwater in the Yangtse Delta Region.

Caveolin-1 redistribution in human endothelial cells induced by laminar flow and cytokine.

Caveolin-1 is a principal component of caveolae and is involved in signaling transduction in a number of cells. A hypothesis was proposed in this work that mechanical forces due to flow induce caveolin-1 translocation. So the changes of caveolin-1 expression and distribution in cultured endothelial cells (HUVECs) exposed to a steady laminar flow were studied. For comparing with the influence of cytokine, caveolin-1 in the cells stimulated by TNF-alpha was also investigated. Indirect immunofluorescence and double fluorescence labeling showed that in control cells, caveolin-1 was primarily localized on the cell surface, which corresponded to the peripheral distribution of F-actin, and presented some local concentrations. In the cells exposed to a laminar flow (1.0 Pa), caveolin-1 distribution showed a time-dependent variation. After 24 h of shear, the local concentration of caveolin-1 was found, in the most cells, at upstream side of cell body. Also more caveolin-1 molecules were observed in the cells. In contrast, TNF-alpha induced a decrease of caveolin-1 in cells. The redistribution of caveolin-1 seems to be correlated to F-actin organization.