In vitro and in vivo evaluation of effects of Mg-6Zn alloy on tight junction of intestinal epithelial cell

The effects of biodegradable Mg?6Zn alloy on tight junction of intestinal epithelial cells (IEC-6) were investigated. In the in vitro experiments, the cells were exposed to Mg?6Zn alloy extracts with different concentrations (0, 20% and 40%) for 1, 3 and 5 d. The real-time polymerase chain reaction (PCR) results show that when the cells are treated with 40% and 20% extracts, the expression of Zona Occludens 1 (ZO-1) and Occludin increase as compared with those in the control group. In the in vivo experiments, Mg?6Zn alloy and titanium staples were implanted into rabbits’ intestinal tract for 1, 2 and 3 weeks. By immunohistochemical staining of peri-implant intestinal tissue, increased expression of Occludin and ZO-1 are observed in the Mg?6Zn alloy groups as compared with those in the titanium and control groups. The results show that Mg?6Zn alloy in intestine may promote the regeneration of tight junction, and the extract with a certain concentration can induce the expression of tight junction related genes in IEC-6 cells.

CWD2000燃气热值分析仪的测量原理与应用

介绍了宝钢集团不锈钢配套工程石灰窑中所使用的燃气热值分析仪的原理、理论计算依据，以及在使用和维护中要注意的一些问题。

Expression of Angiopoietin-2 and Vascular Endothelial Growth Factor in Oral Squamous Cell Carcinoma and Its Significance

Objective： To investigate the expression of angiopoietin-2 （Ang-2） and vascular endothelialcell growth factor （VEGF） in oral squamous cell carcinoma （OSCC） and their correlations with clinicopathologic parameters, angiogenesis and vessel maturation of OSCC. Methods： The expression of Ang-2 and VEGF was detected in 41 speciments of human OSCC, 30 adjacent noncancerous oral tissues and 10 specimens of normal oral mucosa by conventional immumohistochemistry. Microvessel density （MVD） and vessel maturation index （VMI） were also assessed by double-labelling immumohistochemistry staining against CD34, a marker of pan-endothelial cells, and that against alpha-smooth muscle actin （α-SMA）, a marker of mural cells （pericytes/smooth muscle cells）. Results： The positive expression rate of Ang-2 and VEGF in 41 OSCC tissues was 51.22% and 63.42%, respectively. The expression of Ang-2 and VEGF was significantly higher in OSCC than in adjacent noncancerous oral tissues （all P〈0.05） and normal oral mucosa （all P〈0.05）. In the clinicopathologic parameters, the Ang-2 expression was closely correlated with tumor lymph node metastasis （P〈0.01） and the VEGF expression was correlated with tumor differentiated degree （P〈0.05）, but there was no significant correlation among the Ang-2 and VEGF expression and patients＇ sex, age and TNM stages （all P〉0.05）. The MVD of OSCC positive for both Ang-2 and VEGF was significantly higher than that of OSCC negative for both Ang-2 and VEGF （P〈0.05）. The VMI of OSCC positive for Ang-2 was significantly lower than that of OSCC negative for Ang-2 （P〈0.05）. When Ang-2 expression was combined with the staus of VEGF expression, MVD of OSCC positive for both Ang-2 and VEGF was the highest （51.08±2.99） as compared with that of other status in patient with OSCC （all P〈0.05）. Conclusion： The overexpression of Ang-2 and VEGF may play a crucial role in the development of OSCC. They are closely associated with angiogenesis and vessel maturation of tumor.

Evaluation of Some Physical Properties of Cucumber （Cucumis sativus L.）

Cucumber is one of the important vegetables in many countries. Information about physical properties of cucumber is necessary for designing, grading, sorting and processing operations. In this study, some physical properties such as diameter, length, height, and weight of three varieties of cucumber （Green Gold, Dharwad, and Super Dominus） were measured. The results revealed that there was no significant difference （P〈0.01） in the density values of the studied varieties, but regarding other physical properties there were a significant difference （P〈0.01） among them. The average density for Green Gold, Dharwad and Super Dominus were 0.98, 0.95 and 0.94 g/cm^3, respectively. Green Gold cucumber had the highest diameter, volume, weight, flesh diameter, geometric mean diameter and sphericity. Dharwad and Super Dominus varieties with 15.49 cm length and 4.61 length to diameter ratio had the highest length and length to diameter ratio, respectively. Smallest skin thickness （1.48 cm） was for Super Dominus. Surface area of Green Gold, Dharwad and Super Dominus were 192.29, 192.4 and 131.2 cm^2. As well as there was a high and positive correlation between weight and volume in the studied varieties. There was a non-significant and low correlation （0.56） between diameter and length in Super Dominus. There was also a high and positive correlation between diameter and geometric mean diameter in all the varieties.

Correlative studies on uPA mRNA and uPAR mRNA expression with vascular endothelial growth factor, microvessel density, progression and survival time of patients with gastric cancer

AIM： To investigate the correlations between the expression of urokinase-type plasminogen activator （uPA） mRNA, uPA receptor （uPAR） mRNA and vascular endothelial growth factor （VEGF） protein and clinicopathologic features, microvessel density （MVD） and survival time. METHODS： In situ hybridization and immuno-histochemistry techniques were used to study the expressions of uPA mRNA, uPAR mRNA, VEGF and CD34 protein in 105 gastric carcinoma specimens. RESULTS： Expressions of uPA mRNA, uPAR mRNA and VEGF protein were observed in 61 （58.1%） cases, 70 （66.7%） cases and 67 （63.8%） cases, respectively. The uPA mRNA and uPAR mRNA positive expression rates in infiltrating-type cases （73.7%, 75.4%）, stage Ⅲ- Ⅳ （72.1%, 75.4%）, vessel invasion （63.2%, 69.9%）, lymphatic metastasis （67.1%, 74.4%） and distant metastasis （88.1%, 85.7%） were significantly higher than those of the expanding-type （χ^2 = 15.57, P = 0.001; χ^2 = 6.91, P = 0.046）, stage Ⅰ-Ⅱ （χ^2 = 19.22, P = 0.001; χ^2 = 16.75, P = 0.001）, non-vessel invasion （χ^2 = 11.92, P = 0.006; χ^2 = 14.15, P = 0.002）, non- lymphatic metastasis （χ^2 = 28.41, P = 0.001; χ^2 = 22.5, P = 0.005） and non-distant metastasis （χ^2 = 12.32, P = 0.004; χ^2 = 17.42, P = 0.002; χ^2 = 11.25, P = 0.012; χ^2 = 18.12, P = 0.002）.The VEGF positive expression rates in infiltrating-type cases （75.4%）, stage Ⅲ-Ⅳ （88.5%）, vessel invasion （82.9%）, lymphatic metastasis （84.3%） and distant metastasis （95.2%） were significantly higher than those of the expanding-type （χ^2 = 9.61, P = 0.021）,stage Ⅰ-Ⅱ （χ^2 = 16.66, P = 0.001）, non-vessel invasion （χ^2 = 29.38, P = 0.001）, non-lymphatic metastasis （χ^2 = 18.68, P = 0.005）, and non-distant metastasis （χ^2 = 22.72, P = 0.007; χ^2 = 21.62, P = 0.004）. The mean MVD in the specimens positive for the uPA mRNA, uPAR mRNA and VEGF protein was markedly higher than those with negative expression groups. Moreover, a positive relation between MVD and uPA mRNA （rs = 0.199, P = 0.042）, uPAR mRNA （rs = 0.278, P = 0.035）, and VEGF （rs = 0.398, P = 0.048） expressions was observed. The mean survival time in cases with positive uPA mRNA, uPAR mRNA and VEGF protein expression or MVD value ≥54.9 was significantly shorter than those in cases with negative expression or MVD value 〈 54.9. CONCLUSION： uPA and uPAR expressions are correlated with enhanced VEGF-induced tumor angiogenesis and may play a role in invasion and nodal metastasis of gastric carcinoma, thereby serving as prognostic markers of gastric cancer.

Side-on Ignition Compared with Ignition by Laser Driven Compression

Recent results for side-on ignition of uncompressed proton-boron （HB 11） fusion that use the Chu-Bobin side-on ignition with petawatt-picosecond laser pulses is extended to the reaction of helium 3-helium 3 （He3）. The HBll reaction resulted in radioactivity is lower values than from burning coal per generated energy. This was based on the very rare experiments with extreme suppression ofpre-pulses in order to suppress relativistic self-focusing. Subsequently, acceleration of highly directed plasma blocks of modest temperature and ultra-high ion current densities above 10H Amps/cm2 were measured in agreement with earlier derived theory. This permits the conditions of the Chu-Bobin for side-on ignition of solid density fusion. Results for similar neutron lean He3 are reported. A detailed comparison with the usual spherical laser compression and ignition of fusion is given for clarifying the basic differences of the ignition process.

High densities of serotonin and peptide YY cells in the colon of patients with lymphocytic colitis

AIM： TO investigate colonic endocrine cells in lympho- cytic colitis （LC） patients. METHODS： Fifty-seven patients with LC were in- cluded. These patients were 41 females and 16 males, with an average age of 49 years （range 19-84 years）. Twenty-seven subjects that underwent colonoscopy with biopsies were used as controls. These subjects underwent colonoscopy because of gastrointestinal bleeding or health worries, where the source of bleed- ing was identified as haemorrhoids or angiodysplasia. They were 19 females and 8 males with an average age of 49 years （range 18-67 years）. Biopsies from the right and left colon were obtained from both patients and controls during colonoscopy. Biopsies were fixed in 4% buffered paraformaldehyde, embedded in paraffin and cut into 5 μm-thick sections. The sections immunostained by the avidin-biotin-complex method for se- rotonin, peptide YY （PYY）, pancreatic polypeptide （PP） enteroglucagon and somatostatin cells. The cell densi- ties were quantified by computerised image analysis using Olympus software. RESULTS： The colon of both the patient and the control subjects were macroscopically normal. Histo- pathological examination of colon biopsies from con- trols revealed normal histology. All patients fulfilled the diagnosis criteria required for of LC： an increase in intraepithelial lymphocytes （〉 20 lymphocytes/100 epithelial cells） and surface epithelial damage with increased lamina propria plasma cells and absent or minimal crypt architectural distribution. In the colon of both patients and control subjects, serotonin-, PYY-, PP-, enteroglucagon- and somatostatin-immunoreac- tive cells were primarily located in the upper part of the crypts of Lieberk0hn. These cells were basket- or flask-shaped. There was no statistically significant dif- ference between the right and left colon in controls with regards to the densities of serotonin- and PYY- immunoreactive cells （P = 0.9 and 0.1, respectively）. Serotonin cell density in the right colon in controls was 28.9 ± 1.8 and in LC patients 41.6±2.6 （P = 0.008）. In the left colon, the corresponding figures were 28.5± 1.9 and 42.4± 2.9, respectively （P = 0.009）. PYY cell density in the right colon of the controls was 10.1 ± 1 and of LC patients 41 ± 4 （P = 0.00006）. In the left colon, PYY cell density in controls was 6.6± 1.2 and in LC patients 53.3 ± 4.6 （P = 0.00007）. CONCLUSION： The change in serotonin cells could be caused by an interaction between immune cells and serotonin cells, and that of PYY density might be sec- ondary.

Effect of toll-like receptor 3 agonist poly I:C on intestinal mucosa and epithelial barrier function in mouse models of acute colitis

AIM To investigate potential effects of poly I:C on mucosal injury and epithelial barrier disruption in dextran sulfate sodium (DSS)-induced acute colitis. METHODS Thirty C57BL/6 mice were given either regular drinking water (control group) or 2% (w/v) DSS drinking water (model and poly I:C groups) ad libitum for 7 d. Poly I:C was administrated subcutaneously (20 mu g/mouse) 2 h prior to DSS induction in mice of the poly I:C group. Severity of colitis was evaluated by disease activity index, body weight, colon length, histology and myeloperoxidase (MPO) activity, as well as the production of proinflammatory cytokines, including tumor necrosis factor-a (TNF-alpha), interleukin 17 (IL-17) and interferon-. (IFN-gamma). Intestinal permeability was analyzed by the fluorescein isothiocyanate labeled-dextran (FITC-D) method. Ultrastructural features of the colon tissue were observed under electron microscopy. Expressions of tight junction (TJ) proteins, including zo-1, occludin and claudin-1, were measured by immunohistochemistry/immunofluorescence, Western blot and real-time quantitative polymerase chain reaction (RT-qPCR). RESULTS DSS caused significant damage to the colon tissue in the model group. Administration of poly I:C dramatically protected against DSS-induced colitis, as demonstrated by less body weight loss, lower disease activity index score, longer colon length, colonic MPO activity, and improved macroscopic and histological scores. It also ameliorated DSS-induced ultrastructural changes of the colon epithelium, as observed under scanning electron microscopy, as well as FITC-D permeability. The mRNA and protein expressions of TJ protein, zo-1, occludin and claudin-1 were also found to be significantly enhanced in the poly I:C group, as determined by immunohistochemistry/immunofluorescence, Western blot and RT-qPCR. By contrast, poly I:C pretreatment markedly reversed the DSS-induced up-regulated expressions of the inflammatory cytokines TNF-alpha, IL-17 and IFN-gamma. CONCLUSION Our study suggested that poly I:C may protect against DSS-induced colitis through maintaining integrity of the epithelial barrier and regulating innate immune responses, which may shed light on the therapeutic potential of poly I:C in human colitis.

Hypoxia training attenuates left ventricular remodeling in rabbit with myocardial infarction

Objective Previous studies showed that hypoxia preconditioning could protect cardiac function against subsequent myo-cardial infarction injury. However, the effect of hypoxia on left ventricular after myocardial infarction is still unclear. This study therefore aims to investigate the effects of hypoxia training on left ventricular remodeling in rabbits post myocardial infarction. Methods Adult male rabbits were randomly divided into three groups： group SO （sham operated）, group MI （myocardial infarc-tion only） and group MI-HT （myocardial infarction plus hypoxia training）. Myocardial infarction was induced by left ventricular branch ligation. Hypoxia training was performed in a hypobaric chamber （having equivalent condition at an altitude of 4000 m, FiO214.9%） for 1 h/day, 5 days/week for four weeks. At the endpoints, vascular endothelial growth factor （VEGF） in the plasma was measured. Infarct size and capillary density were detected by histology. Left ventricular remodeling and function were as-sessed by echocardiography.Results After the 4-week experiment, compared with the group SO, plasma VEGF levels in groups MI （130.27 ± 18.58 pg/mL,P〈 0.01） and MI-HT （181.93 ± 20.29 pg/mL,P〈 0.01） were significantly increased. Infarct size in Group MI-HT （29.67% ± 7.73%） was deceased remarkably, while its capillary density （816.0 ± 122.2/mm2） was significantly increased. For both groups MI and MI-HT, left ventricular end-diastolic and end-systolic dimensions were increased whereas left ventricular ejection fraction was decreased. However, compared with group MI, group MI-HT diminished left ventricular end-diastolic （15.86 ± 1.09 mm,P〈 0.05） and end-systolic dimensions （12.10 ± 1.20 mm,P〈 0.01） significantly and im-proved left ventricular ejection fraction （54.39 ± 12.74 mm,P〈 0.05）.ConclusionHypoxia training may improve left ven-tricular function and reduce remodeling via angiogenesis in rabbits with MI.

Association of serum vascular endothelial growth factor-C and lymphatic vessel density with lymph node metastasis and prognosis of patients with gastric cancer

AIM： To investigate whether serum vascular endothelial growth factor-C （SVEGF-C）, VEGF-C, and lymphatic vessel density （LVD） in tumor tissues are related to lymph node metastasis （LNM） and prognosis in gastric cancer. METHODS： SVEGF-C levels of 80 gastric cancer patients and 20 healthy donors were examined using ELISA. VEGF-C expression and LVD were examined using immunohistochemical staining. Kaplan-Meier survival analysis was performed to determine their influence on the prognosis of the patients. RESULTS： The SVEGF-C level in gastric cancer patients （595.9 ± 201.0 ng/L） was significantly higher （P = 0.000） than controls （360.0 ± 97.4 ng/L）. Both SVEGF-C and LVD were significantly higher in poorly differentiated adenocarcinomas, T3 and T4, LNM, distant metastasis, and pTNM groups Ⅲ and Ⅳ （P = 0.000）. The sensitivity and specificity of SVEGF-C for predicting LNM were 82.8% and 81.8%, respectively （cut-off = 542.5 ng/L）. The positive expression rate of VEGF-C was significantly higher in cancerous than in normal tissues （65% vs 20%; P = 0.001）. VEGF-C expression up-regulation was significantly related to differentiation, depth of invasion, LNM, distant metastasis, and pTNM stage （P = 0.000）. LVD was 10.7 ± 3.1/200 HP in the experimental group vs 4.9 ± 1.3/200 HP in controls （P = 0.000）; LVD in cancerous tissues with and without LNM was 12.0 ± 2.7/200 HP vs 7.6 ± 0.5/200 HP, respectively （P = 0.000）. SVEGF-C and LVD were significantly higher in VEGF-C positive than in negative patients （P = 0.000）; SVEGF-C level was related to LVD （P = 0.000）. Kaplan-Meier survival analysis factors predicating poor prognosis were： SVEGF-C level （P = 0.001）, VEGF-C expression and LVD （both P = 0.000）. CONCLUSION： SVEGF-C level, VEGF-C and LVD are related to LNI and poor prognosis of patients with gastric cancer, SVEGF-C may be a biomarker for LNI in gastric cancer,

The effects of vascular endothelial growth factor and microvessel density in the fibromyoma uteri

Objective： To investigate vascular endothelial growth factor （VEGF） expression and microvessel density （MVD） on the fibromyoma uteri treated with mifepristone. Methods： VEGF expression and MVD were counted on 60 cases of the fibromyoma uteri by SP method, including 40 cases of mifepristone treated and 20 cases of untreated patients as controlled group. Results： VEGF positive expression rate and MVD in treated group were 3715% and 9.90 ＋ 5.95, which were lower than those in controlled group （80% and 16.36 ＋ 2.07; P 〈 0.05）. Meanwhile, in treated group, those in marked shrink in tumor size sub-group were lower than in not obvious sub-group （12.0% and 7.89 ＋ 4.36 vs. 80% and 11,29 ＋ 3.10; P 〈 0.05）. Conclusion： VEGF and MVD expression decreases in the fibromyoma uteri after treatment with mifepristone, suggesting that mifepristone could inhibit angiogenesis and blood supply resulting in tumor shrink.

The Inhibitory Effects of Arresten Protein on Tumor Formation

Objective To examine the inhibitory effects of recombinant purified arresten on tumor formation. Methods Purified arresten protein was incubated with human umbilical vein endothelial cells (HUVECs) and HeLa cells in vitro. The effect on proliferation of HUVECs and HeLa cells was examined using 3-(4,5)-dimethylthiahiazo (-z-y1)-3,5-di-phenytetrazoliumromide assay, and apoptosis of these cells monitored by flow cytometry. The effect on migration of HUVECs and HeLa cells was examined by Boyden chamber. Twenty colon carcinoma-bearing C67BL/6 mice were used to investigate the antitumor effects of arresten protein. The mice were randomly divided into arresten treatment group (n=10) and control group (n=10). The microvessel densities of the tumors were measured by immunohistochemical staining with anti-CD31 monoclonal antibody. Results Arresten inhibited the proliferation and migration of HUVECs in a dose-dependent manner while promoting apoptosis. However, arresten had no significant effects on the proliferation and apoptosis of HeLa cells. The migration of HeLa cells was modestly inhibited by arresten. The arresten treatment group of mice showed no weight loss or unusual behavior during the course of treatment, and the tumor growth was significantly decreased; in contrast, the control group of mice exhibited rapidly growing tumors and cachexia. A dramatically decreased microvessel density in tumor tissues was found in arresten-treated mice compared with that in the control mice. Conclusion Arresten can inhibit tumor growth through inhibition of tumor angiogenesis.

Prognostic significance of erythropoietin and erythropoietin receptor in gastric adenocarcinoma

AIM: To investigate the expression of Erythropoietin (Epo) and its receptor (EpoR) in gastric adenocarcinoma (GAC) and the correlation with angiogenesis and clinicopathological features. METHODS: The expressions of Epo, EpoR and vascular endothelial growth factor (VEGF), as well as mi-crovessel density were evaluated in 172 GAC biopsies by immunohistochemical staining. The correlations between these parameters and patient’s clinicopathological features were analyzed statistically. RESULTS: The proportion of Epo and EpoR alterations in GAC was higher than that in adjacent normal mucosa (P = 0.035 and 0.030). Epo high-expression was associ-ated with EpoR high-expression, Lauren type, extensivelymph node metastasis and advanced stage of GAC (P = 0.018, 0.018, 0.004 and 0), while EpoR expression was linked with older age, World Health Organization type, extensive lymph node metastasis and advanced stage (P = 0.001, 0.013, 0.008 and 0.001). VEGF high expression was significantly correlated with EpoR low-expression, Lauren type, extensive lymph node metastasis and advanced stage (P = 0.001, 0.001, 0.001 and 0.007). The expression of Epo or EpoR was associated with microvessel density (P = 0.004 and 0.046). On multivariate analysis, only lymph node metastasis, abnormal Epo expression and tumor nodes metastases stage were independently associated with survival. In addition, a strong association with the immunohistochemical expression of EpoR and the angiogenic protein, VEGF, was noted. CONCLUSION: Increased expression of Epo and EpoR may play a signif icant role in the carcinogenesis, angiogenesis and progression of GAC. Epo may be an inde-pendent prognostic factor.

The Estimation of the Number of Zeros of the Abelian Integrals for a Class of Hamiltonian Systems

In this paper, we discuss the estimation of the number of zeros of the Abelian integral for the quadratic system which has a periodic region with a parabola and a straight line as its boundary when we perturb the system inside the class of all polynomial systems of degree n. The main result is that the upper bound for the number of zeros of the Abelian integral associated to this system is 3n-1.

Vascular endothelial growth factor and microvessel density for detection and prognostic evaluation of invasive breast cancer

Objective The purpose of this study was to evaluate the distribution of vascular endothelial growth factor （VEGF） and CD105-microvessel density （MVD）in invasive breast carcinomas. We also aimed to analyze the relationship between VEGF and MVD expression with other standard prognostic parameters associated with invasive breast cancer, such as size, grade, stage of the cancer, metastases, and tumor recurrence. Methods immunohistochemistry via the Ultra SensitiveTM S-P method was used to detect VEGF and MVD expression in 128 cases of invasive breast carcinoma. Specimens were evaluated for CD105 expression. Positively stained microvessels were counted in dense vascular loci under 400x magnification, MVD in the peripheral area adjacent to the lesion and in the central, area within the lesion in invasive breast carcinomas and benign leisions groups were also assessed. Fifty cases of benign breast disease tissue were selected as the control group. Results Results showed that 64.1% of invasive breast cancer samples were VEGF-positive, higher than in benign breast disease tissue （22.0%, P 〈 0.05）. There was a positive correlation between VEGF overexpression and histological grade, lymph node metastasis, and distant metastasis of invasive breast cancer. VEGF expression was not related to age or size of the tumor （P 〉 0.05）. MVD of the peripheral area adjacent to the lesion was significantly higher than those central area within the lesion in both invasive breast cancer and benignbreast disease groups （P 〈 0.01 for each group）. There were significant differences in the mean CD105-MVD, between invasive breast tumors with a histological grade of Ⅰ or Ⅱ and grade Ⅲ; between tumors with lymph node or distant metastasis; and between patients with or without recurrence （P 〈 0.05）. However, there was no difference in the mean MVD between the two age groups （≤ 50 years vs. 〉 50 years） or the two tumor diameter groups （〈 2 cm vs. 〉 2 cm）, P 〉 0.05. Conclusion Overexpression of VEGF and MVD may be important biological.markers for invasion and lymph node and distant metastases of invasive breast cancer. Combined detection of the two tumor markers could provide better prognostic monitoring for disease recurrence and metastasis, as well as aid with clinical staging of breast tumors. Prediction of the risk for metastasis and recurrence, as well as recurrence patterns based on VEGF and MVD post-surgery, could aid design of better follow-up regimens and appropriate treatment strategies for breast cancer patients.

Percutaneous estrogen in prevention of early postmenopausal bone loss in Chinese women

OBJECTIVE: To identify the optimal dosage of 17beta-estradiol gel + oral progestin for preventing bone loss in postmenopausal Chinese women. METHODS: A 3-year open label, randomized, prospective clinical trial was conducted. Sixty healthy women who had been postmenopausal for 1 to 5 years were recruited and divided into following 4 groups: group 1, percutaneous gel 17beta-estradiol (E(2)) 1.5 mg/d plus micronized progesterone (MP) 100 mg/d; group 2, percutaneous gel 17beta-estradiol (E(2)) 1.5 mg/d plus medroxyprogesterone acetate (MPA) 2 mg/d; group 3, percutaneous gel 17beta-estradiol (E(2)) 0.75 mg/d plus micronized progesterone (MP) 100 mg/d; and group 4, percutaneous gel 17beta-estradiol (E(2)) 0.75 mg/d plus medroxyprogesterone acetate (MPA) 2 mg/d. Estrogen and progestin were given continuously for 25 days per month. Bone mineral density (BMD) was measured using quantitative computed tomography (QCT) for trabecular bone of L2-5 and dual energy X-ray absorptiometry (DEXA) for L2-4 and hip 5 times during the trial at baseline and at the 6-, 12-, 18-, 24- and 36-month visits. RESULTS: Fifty-nine patients (98.3%, 59/60) stayed in the study for 1 year, 56 patients (93.3%, 56/60) for 2 years, and 51 (85%, 51/50) for 3 years. On average, menopausal symptoms were relieved by 80% after 6 months of treatment. By the 24th month, the mean increase in BMD ranged from 4.3% to 7.5% in trabecular bone; and by the 36th month, it ranged from 4.2% to 6.2% in L2-4 and 1.61% to 3.77% in the neck. There were significant difference after treatment (P 0.05) was found in improvement of symptoms, levels of bone markers or BMD. CONCLUSION: A daily dose of estradiol gel, either 0.75 mg or 1.5 mg, is effective in preventing early postmenopausal bone loss and relieving menopausal symptoms. After 3-year treatment, spinal BMD could increase steadily, so does hip BMD, especially in the first 2 years.

Symmetry energy at subsaturation densities and the neutron skin thickness of ^(208)Pb

The mass-dependent symmetry energy coefficients asym（A） has been extracted by analysing the heavy nuclear mass differences reducing the uncertainties as far as possible in our previous work. Taking advantage of the obtained symmetry energy coefficient asym（A） and the density profiles obtained by switching off the Coulomb interaction in ^208Pb, we calculated the slope parameter L0.11 of the symmetry energy at the density of 0.11 fm^-3. The calculated L0.11 ranges from 40.5 MeV to 60.3 MeV. The slope parameter L0.11 of the symmetry energy at the density of 0.11 fm^-3 is also calculated directly with Skyrme interactions for nuclear matter and is found to have a fine linear relation with the neutron skin thickness of ^208spb, which is the difference of the neutron and proton rms radii of the nucleus. With the linear relation the neutron skin thickness ARnp of ^208spb is predicted to be 0.15-0.21 fm.

Dating a 109.9 m ice core from Dome A (East Antarctica) with volcanic records and a firn densification model

A 109.9 m ice core was extracted at a location about 300 m away from the Dome A summit （80°00′S, 77°21″E） by the Chinese team of the International Trans-Antarctic Science Expedition （ITASE） during the 21st Chinese National Antarctica Research Expedition （CHINARE） in January 2005. Two independent methods were used for dating the ice core, volcanic event markers shown by prominent non-sea-salt sulfate （nss-SO4^2-） and the Herron and Langway （H-L） firn densification model. Six promi- nent volcanic events （Agung 1963 AD, Tambora 1815 AD, Kuwae 1453 AD, Unknown 1259 AD, Taupo 186 AD and Pinatubo 1050 BC） were identified by comparison with other Antarctic ice cores. Based on the mean accumulation rates be- tween adjacent events, we estimate the age at the tim pore close-off depth （102 m） was 3516±100 a BP. This is the oldest close-off age ever reported from the Antarctic and the Greenland ice sheets. Calculations using the H-L model show that the age at the same depth is 3581±100 a BP. The two dating techniques differ by 65 years, or -1.8% of the record. We calculated the bottom age of the ice core as 4009±150 a BP using the volcanic dating method and 4115±150 a BP using the H-L model method.

Neural circuits and temporal plasticity in hindlimb representation of rat primary somatosensory cortex:revisited by multi-electrode array on brain slices

Objective The well-established planar multi-electrode array recording technique was used to investigate neural circuits and temporal plasticity in the hindlimb representation of the rat primary somatosensory cortex （S1 area） . Methods Freshly dissociated acute brain slices of rats were subject to constant perfusion with oxygenated artificial cerebrospinal fluid （95% O2 and 5% CO2） , and were mounted on a Med64 probe （64 electrodes, 8×8 array） for simultaneous multi-site electrophysiological recordings. Current sources and sinks across all the 64 electrodes were transformed into two-dimensional current source density images by bilinear interpolation at each point of the 64 electrodes. Results The local intracortical connection, which is involved in mediation of downward information flow across layers II-VI, was identified by electrical stimulation （ES） at layers II-III. The thalamocortical connection, which is mainly involved in mediation of upward information flow across layers II-IV, was also characterized by ES at layer IV. The thalamocortical afferent projections were likely to make more synaptic contacts with S1 neurons than the intracortical connections did. Moreover, the S1 area was shown to be more easily activated and more intensively innervated by the thalamocortical afferent projections than by the intracortical connections. Finally, bursting conditioning stimulus （CS） applied within layer IV of the S1 area could success-fully induce long-term potentiation （LTP） in 5 of the 6 slices （83.3%） , while the same CS application at layers II-III induced no LTP in any of the 6 tested slices. Conclusion The rat hindlimb representation of S1 area is likely to have at least 2 patterns of neural circuits on brain slices： one is the intracortical circuit （ICC） formed by interlaminar connections from layers II-III, and the other is the thalamocortical circuit （TCC） mediated by afferent connections from layer IV. Besides, ICC of the S1 area is spatially limited, with less plasticity, while TCC is spatially extensive and exhibits a better plasticity in response to somatosensory afferent stimulation. The present data provide a useful experimental model for further studying microcircuit properties in S1 cortex at the network level in vitro.