[The value of preservation of subvalvular structures in patients with mitral and aortic valve replacement surgery and its effect on left ventricular contractility]

Objective: To discuss the clinical value of preserving subvalvular structure in mitral and aortic valve replacement surgery and its effect on left ventricular contractility. Methods: A total of 97 patients who underwent mitral valve replacement surgery in the Adult Cardiac Surgery of Heart Center of Henan Provincial People's Hospital, Central China Fuwai Hospital from June 2016 to December 2018 were selected as the research subjects, of whom 45 cases were preserved subvalvular structure and 52 cases were in the total resection group (intraoperative total resection of the mitral valve and subvalvular chordae tendineae). General cardiac function indexes and left ventricular function quantitative indexes were compared before and in 3 months and 6 months after the operation of the two groups; The changes of the overall longitudinal strain of the long axis of the apex and the overall circumferential strain of the short axis of the left ventricle determined by the two-dimensional speckle tracking technology were compared before and after the operation. Results: The ages of the patients in the preservation group and the total resection group were (41.8±11.3) and (43.3±10.6) years old, respectively, and the male proportions were 58.0% (26 cases) and 44.0% (23 cases), respectively, with no significant difference (all P>0.05). The aortic occlusion time and cardiopulmonary bypass time of the patients in the preservation group were (57.8±4.5) and (78.6±6.7) min, respectively, which were longer than those in the total resection group [(48.1±4.4) and (48.1±4.4) min, respectively] (all P<0.05). The left atrial pressure of the patients in the preservation group at shutdown was (8.4±1.8) mmHg (1 mmHg=0.133 kPa), which was lower than that of the total resection group (11.3±2.5) mmHg (P<0.001). There were interaction effects between groups and time in regards to the left ventricular end-diastolic diameter ( LVEDD ), left ventricular ejection fraction ( LVEF ) and Tei index, as well as the strain rate of mitral annulus and left ventricular wall of interventricular septum of the preservation group and the total resection group (all P<0.05). LVEDD and LVEF of patients in the preservation group at 3rd month after operation were (44.7±4.0) mm and (45.5±4.2) mm, and at 6th months were (56.5±4.9)% and (58.8±5.0)%, respectively, all larger than (42.7±3.6) mm and (42.7±3.6) mm, (54.5±4.6)% and (56.3±4.8)% of the total resection group. The measured value of LVESD in the preservation group at 3rd month after surgery was (32.6±3.2) mm, which was greater than that in the total resection group (31.2±3.4) mm (P<0.05). The Tei index of patients in the preservation group at 3rd and 6th months after surgery were 1.0±0.2 and 0.8±0.2, respectively, which were lower than those in the total resection group 1.2±0.3 and 0.9±0.2 (all P<0.05). Conclusion: Preserving the subvalvular structure during mitral valve replacement surgery can better improve the patient's left ventricular function and left ventricular systolic capacity.

Ectopic expression of a combination of 5 genes detects high risk forms of T-cell acute lymphoblastic leukemia

BACKGROUND

T cell acute lymphoblastic leukemia (T-ALL) defines a group of hematological malignancies with heterogeneous aggressiveness and highly variable outcome, making therapeutic decisions a challenging task. We tried to discover new predictive model for T-ALL before treatment by using a specific pipeline designed to discover aberrantly active gene.

RESULTS

The expression of 18 genes was significantly associated with shorter survival, including ACTRT2, GOT1L1, SPATA45, TOPAZ1 and ZPBP (5-GEC), which were used as a basis to design a prognostic classifier for T-ALL patients. The molecular characterization of the 5-GEC positive T-ALL unveiled specific characteristics inherent to the most aggressive T leukemic cells, including a drastic shut-down of genes located on the mitochondrial genome and an upregulation of histone genes, the latter characterizing high risk forms in adult patients. These cases fail to respond to the induction treatment, since 5-GEC either predicted positive minimal residual disease (MRD) or a short-term relapse in MRD negative patients.

CONCLUSION

Overall, our investigations led to the discovery of a homogenous group of leukemic cells with profound alterations of their biology. It also resulted in an accurate predictive tool that could significantly improve the management of T-ALL patients.

[Analysis of occurrence and treatment of perioperative complete atrioventricular block by transcatheter aortic valve implantation]

Objective: To retrospectively analyze the occurrence and treatment of perioperative complete atrioventricular block (CAVB) by transcatheter aortic valve implantation (TAVI). Methods: A total of 65 patients who underwent TAVI via femoral artery in the Heart Center of Henan People's Hospital from October 2017 to May 2021 were enrolled. Perioperative data of patients were recorded. The patients were divided into two groups according to whether complete atrioventricular block was occurred during TAVI: complete atrioventricular block group (Group CAVB) and non-complete atrioventricular block group (Group NCAVB). Multivariate logistic regression model was used to analyze the risk factors of complete atrioventricular block during transcatheter aortic valve implantation. The incidence of perioperative complications were recorded. Results: The patients age was (69.1±7.3) years old. and there were 35 males and 30 femals. There were 15 patients in group CAVB with complete atrioventricular block and 50 patients in group NCAVB. Multivariate analysis showed that preoperative right bundle branch block [OR (95%CI) vs 3.325 (2.132-13.061), P=0.005] and severe aortic valve calcification [OR (95%CI) vs 1.271 (1.052-3.326), P=0.030] were independent correlative factors for CAVB during TAVI perioperative period. The implantation rate of permanent pacemaker in group CAVB was 73.3% (11 cases), which was higher than 6.0% (3 cases) in group NCAVB (P<0.001). Conclusions: It indicated that preoperative right bundle branch block and severe aortic valve calcification are correlative factors for complete atrioventricular block for TAVI. The implantation rate of permanent pacemaker in complete atrioventricular block group increased significantly.

Modeling and improvement of a low-frequency micro-accelerometer

A sensitivity- and resolution-improving method for a low-frequency micro-vibration accelerometer is presented in this paper. A sensitivity model of the measurement system is derived and established. The key parameters that limit the sensitivity and the resolution of the accelerometer were identified through the sensitivity coefficient analysis method. The structural parameters and the signal process method were then optimized. Experimental results show that the sensitivity of the accelerometer has improved from 1.10 V/(m/s²) to 19.21 V/(m/s²), and the resolution has improved from 1.47 mm/s² to 0.21 mm/s². The lowest working frequency range has expanded from 1 Hz to 0.7 Hz. The presented method is effective and cheap and can be applied to other sensors.

[Clinical study on preserving right gastroepiploic vein during laparoscopic right hemicolectomy]

Objective: The operative approach and steps of laparoscopic right hemicolon cancer radical resection have been standardlized and professional consensus has been reached. However, some detailed issues such as the handling of Henle's trunk and whether to preserve the right gastroepiploic vein (RGEV) still remain controversial. This study investigates the safety, feasibility, short- and long-term outcomes of preserving RGEV during laparoscopic right hemicolectomy. Methods: A retrospective cohort study was carried out. Clinical data of 92 patients undergoing laparoscopic right hemicolectomy in Taizhou People's Hospital from March 2016 to May 2018 were retrospectively analyzed. All the patients were treated with complete mesocolon resection (CME) and had complete postoperative pathological data and follow-up data. Based on the tumor location, 49 patients preserved RGEV (preservation group) and 43 did not (non-preservation group). Pathological data, postoperative complications, short- and long-term outcomes were compared between the two groups. Results: There were no significant differences in baseline data between the two groups (all P>0.05). No significant differences were found in operation time, intraoperative blood loss, unplanned reoperation, anastomotic leak, number of harvested lymph nodes, number of metastatic lymph node, and time to food intake after surgery between two groups (all P>0.05). Compared with non-preservation group, the preservation group had faster recovery of anal gas passage after operation [(3.1±1.0) days vs. (4.0±1.7) days, t=-2.787, P=0.007], shorter length of hospitalization [(11.5±1.5) days vs. (15.0±7.9) days, t=-2.823, P=0.007], and reduced the hospitalization expenses [(46 000±5000) yuan to (57 000±33 000) yuan, t=-2.076, P=0.044]. No postoperative gastroparesis (PGS) occurred in the preservation group, while 6 cases in the non-preservation group developed gastroparesis during perioperative period (P<0.05). The median time of follow-up time was 31.8 (5.2-43.7) months. The overall survival time of the preservation group and non-preservation group was (35.4±1.8) months and (37.6±1.7) months, respectively without significant difference (P=0.336); the disease-free survival was (32.0±2.2) months and (35.5±2.0) months, respectively without significant difference as well (P=0.201). Conclusions: Dissection of the Henle's truck and preservation of RGEV is safe and feasible during laparoscopic right hemicolectomy, which can significantly reduce the incidence of postoperative gastroparesis, shorten the recovery time of postoperative intestinal function and hospitalization, and decrease the cost of hospitalization. The efficacy of RGEV preservation is similar to non-preservation of RGEV.

[Predictive value of cervical length measured by transvaginal ultrasound during the second and the third trimester of pregnancy for preterm birth in twin pregnancies]

Objective: To investigate the predictive value of cervical length (CL) measured by transvaginal ultrasound for preterm birth <32 weeks, <34 weeks in twin pregnancies in the second and the third trimester of pregnancy. Methods: A total of 490 twin pregnant women with CL measured by transvaginal ultrasound during the second trimester of pregnancy (20-24 weeks) and the third trimester of pregnancy (28-32 weeks) delivered in Peking University Third Hospital, and Tongzhou Maternal and Child Health Hospital from January 2014 to December 2017 were collected, and 161 cases out of which were measured by CL during both the second trimester and the third trimester of pregnancy. Based on the measured gestational weeks, 427 cases were in the second trimester group and 224 cases in the third trimester group. The predictive value of CL for preterm birth was evaluated by calculating the optimal cut-off point with sensitivity and specificity. Logistic regression analysis was used to assess the relationship between CL and preterm birth after adjusting for confounding factors (age of pregnant women, chorionic status, mulipara, assisted reproductive pregnancy and pre-pregnancy body mass index). Results: (1) The median CL of pregnant women in the second trimester group and the third trimester group were 36 mm (33-40 mm) and 28 mm (18-33 mm) respectively. In the second trimester group, 151 cases (35.4%, 151/427) were preterm birth and 276 cases (64.6%, 276/427) were full-term birth; the median CL of preterm and full-term pregnant women were 34 mm (30-37 mm) and 37 mm (34-40 mm), respectively, with significant difference (P<0.01). In the third trimester group, 100 cases (44.6%, 100/224) were preterm birth and 124 cases (55.4%, 124/224) were full-term birth; the median CL of preterm and full-term pregnant women were 22 mm (15-30 mm) and 31 mm (23-34 mm), respectively, with significant difference (P<0.01). (2) Prediction of preterm birth <32 weeks and <34 weeks was performed with CL in the second trimester group. The area under the receiver-operating characteristics curve were 0.78 (95%CI: 0.70-0.86) and 0.71 (95%CI: 0.64-0.79), respectively. The optimal cut-off points were 36.5 mm and 33.5 mm, respectively. After adjusting for confounding factors, CL was inversely associated with preterm birth <32 weeks and <34 weeks of gestation. (3) Prediction of preterm birth <32 weeks and <34 weeks were performed with CL in the third trimester group. The area under the receiver-operating characteristics curve were 0.86 (0.75-0.96) and 0.75 (0.67-0.84), respectively. The optimal cut-off points were 17.5 mm and 18.5 mm, respectively. After adjusting for confounding factors, CL was inversely associated with preterm birth at <32 weeks and <34 weeks of gestation. Conclusions: CL measured by transvaginal ultrasound in the second and the third trimester is a good predictor for preterm birth of twin pregnancy. CL≤36.5 mm and ≤33.5 mm at 20-24 weeks of gestation could predict preterm birth <32 weeks and <34 weeks respectively. CL≤17.5 mm and ≤18.5 mm at 28-32 weeks of gestation could predict preterm birth <32 weeks and <34 weeks respectively.

Dynamics and functional interplay of histone lysine butyrylation, crotonylation, and acetylation in rice under starvation and submergence

BACKGROUND

Histone lysine acylations by short-chain fatty acids are distinct from the widely studied histone lysine acetylation in chromatin, although both modifications are regulated by primary metabolism in mammalian cells. It remains unknown whether and how histone acylation and acetylation interact to regulate gene expression in plants that have distinct regulatory pathways of primary metabolism.

RESULTS

We identify 4 lysine butyrylation (Kbu) sites (H3K14, H4K12, H2BK42, and H2BK134) and 45 crotonylation (Kcr) sites on rice histones by mass spectrometry. Comparative analysis of genome-wide Kbu and Kcr and H3K9ac in combination with RNA sequencing reveals 25,306 genes marked by Kbu and Kcr in rice and more than 95% of H3K9ac-marked genes are marked by both. Kbu and Kcr are enriched at the 5' region of expressed genes. In rice under starvation and submergence, Kbu and Kcr appear to be less dynamic and display changes in different sets of genes compared to H3K9ac. Furthermore, Kbu seems to preferentially poise gene activation by external stresses, rather than internal circadian rhythm which has been shown to be tightly associated with H3K9ac. In addition, we show that rice sirtuin histone deacetylase (SRT2) is involved in the removal of Kcr.

CONCLUSION

Kbu, Kcr, and H3K9ac redundantly mark a large number of active genes but display different responses to external and internal signals. Thus, the proportion of rice histone lysine acetylation and acylation is dynamically regulated by environmental and metabolic cues, which may represent an epigenetic mechanism to fine-tune gene expression for plant adaptation.

[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.

[Effect of miR-19b on the proliferation and apoptosis of P19CL6 cells during the late-stage of cardiac differentiation]

Objective: To explore the effect of miR-19b on the function of P19CL6 cells and its molecular mechanism. Methods: Overexpression of miR-19b was carried out by transfecting miR-19b plasmid into the P19CL6 cells. MTT assay and flow cytometry were used to determine cell growth and apoptosis, respectively. Western blot was used to detect the expression level of Sox6 in P19CL6 cells. ELISA assay was used to detect the expression levels of apoptosis-related genes (Bax, Bcl-2) in P19CL6 cells at late-stage cardiac differentiation. Further online software TargetScan was used to predict the target genes of miR-19b and verified by dual luciferase reporter assay. Results: Our data showed that overexpression of miR-19b in P19CL6 cells significantly increased the cell growth rates and the apoptosis inhibition rates. The ratio of apoptosis-related proteins (Bax/Bcl-2) was significantly reduced. Results from the TargetScan and dual luciferase reporter showed that Sox6 is the direct target of miR-19b. Conclusions: We conclude that miR-19b might promote cell proliferation and inhibits cell apoptosis during the late-stage of cardiac differentiation by targeting Sox6 expression.

Comparative Proteomic Analysis of the Effect of the Four-Herb Chinese Medicine ANBP on Promoting Mouse Skin Wound Healing

Traditional Chinese medicine has great potential to improve wound healing. ANBP, the mixture of 4 Chinese herbs- Agrimoniapilosa, Nelumbonucifera, Boswelliacarteri, and Pollen typhae-is effective in trauma treatment while its mechanism is still elusive. In this study, quantitative proteomics and bioinformatics analyses were performed to decipher the possible roles of ANBP in accelerated wound healing of mouse skin. Among all 3171 identified proteins, 90, 71, 80, and 140 proteins were found to be differently expressed in 6 hours, 3 days, 7 days, and 14 days ANBP-treated tissues compared with corresponding control tissues, respectively. The result showed that different biological processes and pathways were activated at different healing stages. At the early healing stage, ANBP treatment mainly affected several biological processes, including immune and defense response, vascular system restoration, hemostasis and coagulation regulation, lipid metabolism and signal transduction, while muscle tissue, hair, epidermis, extracellular matrix and tissue remodeling related activities were the major events in ANBP promoted later wound healing. This is the first quantitative proteome study of ANBP-treated wound tissues, which provide a new perspective for the mechanism of ANBP accelerated wound healing and is of guiding significance for clinical application of ANBP in trauma disorders cure.

[Feasibility of retrograde approach for percutaneous closure of ventricular septal defect under solely guidance of transesophageal echocardiography]

OBJECTIVE

To evaluate the feasibility of retrograde transcatheter closure of ventricular septal defects (VSD) under trans-esophageal echocardiography (TEE).

METHODS

Twelve patients with VSD, with 4 residual shunt, treated by transcatheter VSD closure under solely guidance of TEE were summarized. Mean age, body weight and average diameter of VSD in 12 cases were (11.58±6.57) years, (31.85±13.28) kg, (5.50±2.20) mm, respectively. All patients were treated by retrograde transcatheter closure under solely guidance of TEE. The post-operative efficiency was estimated by TEE immediately. Patients were followed up by echocardiography, X-ray examination and electrocardiogram at 24 hours, 1, 3 and 6 months after the procedures.

RESULTS

All 12 patients were treated successfully under solely guidance of TEE. The diameter of devices were 5-14 mm. There were 1 case with trivial residual shunt after the procedures immediately. No patients suffered from residual shunt, occluder malposition, peripheral vascular injury and pericardial effusion during the follow-up.

CONCLUSION

Percutaneous transcatheter closure of VSD completely guided by TEE is safe and effective. This method could avoid the radiation and contrast media reaction, and also could simplify the procedure.

Effect of oxygen stoichiometry in LuFe2O(4-δ) and its microstructure observed by aberration-corrected transmission electron microscopy

A series of oxygen deficient LuFe(2)O(4-δ) materials have been prepared under a controlled oxygen partial-pressure atmosphere. Measurements of magnetization reveal that the increase of oxygen deficiencies could evidently depress the ferrimagnetic phase transition temperature (T(N)). In additional to the well-known charge ordering within the (11(-)0) crystal plane, a visible structural modulation with q = (0,1/4.2,7/8) commonly appears on the (100) plane in the oxygen deficient samples. An aberration-corrected transmission electron microscopy study on the oxygen deficient samples demonstrates the presence of oxygen vacancies and local structural distortion. The atomic structural features in correlation with the structural modulation, distortion of the FeO(5) polyhedron and the (001) twinning domains have been also examined.

Multishell intermetallic onions by symmetrical configuration of ordered domains

Ordered domains are utilized to construct new nanostructures, i.e., multishell intermetallic onions, which are formed by symmetrical configuration of ordered domains. Through density-functional theory calculations, we have shown that the energy penalties for introducing antiphase boundaries into the nanoparticles are small in some alloy systems compared to typical surface energies, making it feasible to prepare intermetallic onions by tuning surface energies. The unique surface atomic arrangements would provide opportunities for developing novel materials like efficient catalysts.

Direct subangstrom measurement of surfaces of oxide particles

Using aberration-corrected transmission electron microscopy combined with first-principles calculations, we show that the surface structure of Co3O4, a typical complex oxide, can be directly imaged and quantitatively analyzed at the subangstrom scale. The atomic positions of both light oxygen and heavier cobalt within the surface layers have been measured to an accuracy of several picometers. The surface electronic structure analysis suggests a polarity compensation model based on the electronic polarizability of surface ions.

[The structure and regulation of plant proteinase inhibitor genes and their strategy in pest control]

The diverse plant proteinase inhibitors (PIs) genes from different plant species have been isolated and their products with one or more genes are targeted at different biochemical and physiological process with the insect, and well played a potent defensive role against insects and pathogens. The use of recombinant PIs and synergistic activation to protect plants has been incorporated in integrated pest management program. Though they may not replace the use of chemical pesticides in the near future, but effectively complement it. Currently, the role and mechanism of action for most of these inhibitors are being studied in detail. This article describes the structure of PIs genes, their regulation and expression, and discusses the strategy to develop transgenic plants against phytophagous insects.

[Separation and determination of glibenclamide in xiaotangling tablets by micellar electrokinetic capillary chromatography]

A high performance capillary electrophoresis method has been developed for separation and quantitative analysis of glibenclamide in Xiaotangling tablets. Electrophoretic conditions were as follows: micellar electrokinetic capillary chromatography (MECC) mode, trimethoprimum as internal standard, uncoated fused silica capillary (34.8 cm/39.5 cm(effective/total length), 50 microns i.d.), 25 mmol/L borax-30 mmol/L SDS(pH 9.0), applied voltage 17 kV, (+)-->(-), temperature 28 degrees C, detection wavelength 228 nm, pressure injection 68.95 kPa.s. Glibenclamide was separated successfully from other components within 14 minutes under the optimum conditions, and the relative peak area of glibenclamide increased linearly with the increase of its concentration within the range of 25 mg/L-275 mg/L. The recovery was (100.6 +/- 1.4)%. The method is simple, rapid and well reproducible, and can be used as a reliable tool for the quality control of Chinese traditional medicine containing glibenclamide.

[Separation and determination of baicalin in prescriptions containing Scutellaria baicalensis Georgi by HPCE]

Qingkailing Oral Tonic and Shuanghuanglian Oral Tonic are two kinds of complex formlae of Chinese traditional patent medicine, and both contain Scutellaria baicalensis Georgi. Baicalin is referred to the main active component with functions of dispelling wind-heat to reduce fever and detoxicating, and takes effect on uppering respiratory tract infection and tonsillities. In this work a high performance capillary electrophoresis (HPCE) method was established for separation and quantitative analysis of baicalin in prescriptions containing Scutellaria baicalensis Georgi, based on the mode of capillary zone electrophoresis. Electrophoretic conditions are as follows: uncoated fused silica capillary (34.8/39.5 cm x 50 microns i.d.), 40 mmol/L borax buffer(pH 9.0), applied voltage 17 kV, polarity anode (inlet) to cathode (outlet), temperature 25 degrees C, detection wavelength 285 nm, injection 68.95 kPa x s. Under the optimum conditions, baicalin was separated successfully from other components within 15 minutes. The relative peak area of baicalin increased linearly with the increase of its concentration in the range of 10-640 mg/L. The recoveries were (100.31 +/- 1.98)% for Qingkailing Oral Tonic and (100.60 +/- 2.36)% for Shuanghuanglian Oral Tonic. The analytical results demonstrate the method is simple, rapid and well reproducible, and can be used as a reliable tool for the quality control of Chinese traditional medicines containing Scutellaria baicalensis Georgi.

Effect of high energy electron irradiation on the electromechanical properties of poly (vinylidene fluoride-trifluorethylene) 50/50 and 65/35 copolymers

High energy electron irradiation with a broad range dosage was carried out on poly(vinylidene fluoride trifluorethylene) copolymer 65/35 mol% and 50/50 mol% films at different temperatures from room temperature to a temperature close to the melt temperature. The effect of irradiation on the properties of the films, such as electric field-induced strain, dielectric and polarisation behaviors, and mechanical modulus, is presented. The irradiated films can exhibit a very large electric field-induced strain, more than 4.5% longitudinal strain, and 3% transverse strain. The transverse strain of the stretched film can compare with the longitudinal strain; that of the unstretched film is much smaller than the longitudinal strain. With regard to the dielectric and polarization behaviors, we found that irradiation changes the copolymer from a typical ferroelectric to a relaxor ferroelectric in which the behavior of microregions under the electric field plays the key role. Between the two copolymers studied, we found that the 65/35 copolymer is preferred for both longitudinal and transverse strain generation. A model is proposed to explain the experimental results that the amplitude of the charge electrostrictive coefficient (Q) increases with decreasing crystallinity.

[Determination of baicalin and chlorogenic acid in yinhuang granule by capillary electrophoresis]

Yinhuang Granule is a kind of complex formulae made up of extract of Flos lonicerae and that of Radix scutellariae, of the fuctions of dispelling wind-heat to reduce fever, detoxicating, relieving inflammation, promoting urination and tranquilizimg the mind and can be applied to upper respiratory tract infection and tonsillitis. Baicalin and chlorogenic acid are referred to main effective components of it. In this paper, the separation and determination of baicalin and chlorogenic acid in Yinhuang Granule by capillary electrophoresis is described. The experimental conditions are stated as follow: separation column: bare fused-sillica capillary (50 microns i.d., 370 microns o.d., total length 47 cm, 40 cm from the inlet to UV detector); electrolyte: 25 mmol/L borax, pH 8.5; detection wavelength: 310 nm; sampling: 17 kPa.s; running voltage: 25 kV, polarity from anode (inlet) to cathode (outlelt); temperature: 25 degrees C; internal standard: p-nitrobenzoic acid. The linear ranges of determination for baicalin and chlorogenic acid were 160-960 mg/L(r = 0.9993, RSD = 1.76%-2.33%) and 80-960 mg/L(r = 0.9989, RSD = 1.07%-2.51%), respectively. The recoveries of baicalin and chlorogenic acid were (102.09 + 1.74)% (RSD = 1.71%, n = 6) and (99.81 + 3.11)% (RSD = 3.12%, n = 6). The method is simple, fast and accurate. It can be used for the quality control of Yinhuang Granule and its related Chinese medicines.

Baseband integrated acousto-optic frequency shifter/modulator module for fiber optic at 1.3 mum

A baseband integrated acoustooptic (AO) frequency shifter/modulator module that consists of a pair of titanium-indiffused proton-exchanged (TIPE) waveguide lenses and a pair of cascaded guided-wave AO Bragg cells has been realized in a Y-cut LiNbO(3) waveguide substrate 0.1 cmx1.0 cmx2.0 cm in size. A device module operating at the optical wavelength of 1.3 mum has provided a -3-dB tunable bandwidth of 120 MHz at baseband. The frequency-shifted or -modulated light propagates in a fixed direction, irrespective of the magnitude of frequency shift or modulation, and is focused into a spot (FWHM) of 6.2-mum size on the output edge of the waveguide. Accordingly, this optical frequency shifter/module can be directly interfaced with single-mode optical fibers to facilitate applications in fiber optic systems.

The antitumor effects of qigong-emitted external Qi and its influence on the immunologic functions of tumor-bearing mice

By utilizing murine tumor models bearing Ehrlich ascites carcinoma (EAC) and ascitic Sarcoma-180 (S-180), we investigated the in vivo antitumor effects of QEQ or/and the chemotherapeutic agent cyclophosphamide (CY) and their influence on the splenic natural killer (NK) activity, macrophage-mediated tumor cytolysis (MTC) activity and interleukin-2 (IL-2) production level of different groups of TBM. The results demonstrate that Qigong-emitted external Qi (QEQ) has inhibitory effects on tumor growth of tumor-bearing mice (TBM) and enhancing effects on antitumor immunologic functions of the tumor host simultaneously. Moreover, when used in combination with CY, QEQ can not only significantly increase the antitumor efficacy, but also markedly improve the compromised antitumor immunologic functions of the tumor host. Therefore, our findings suggest that in clinical practice of cancer treatment Qigong therapy in combination with conventional therapy (such as chemotherapy) is a treatment regimen worth recommending.

Molecular markers for the agouti coat color locus of the mouse

The agouti (a) coat color locus of the mouse acts within the microenvironment of the hair follicle to control the relative amount and distribution of yellow and black pigment in the coat hairs. Over 18 different mutations with complex dominance relationships have been described at this locus. The lethal yellow (Ay) mutation is the top dominant of this series and is uniquely associated with an endogenous provirus, Emv-15, in three highly inbred strains. However, we report here that it is unlikely that the provirus itself causes the Ay-associated alteration in coat color, since one strain of mice (YBR-Ay/a) lacks the provirus but still retains a yellow coat color. Using single-copy mouse DNA sequences from the regions flanking Emv-15 we have detected three patterns of restriction fragment length polymorphisms (RFLPs) within this region that can be used as molecular markers for different agouti locus alleles: a wild-type agouti (A) pattern, a pattern which generally cosegregates with the nonagouti (a) mutation, and a pattern which is specific to Emv-15. We have used these RFLPs and a panel of 28 recombinant inbred mouse strains to determine the genetic linkage of these sequences with the agouti locus and have found complete concordance between the two (95% confidence limit of 0.00 to 3.79 centimorgans). We have also physically mapped these sequences by in situ hybridization to band H1 of chromosome 2, thus directly confirming previous assignments of the location of the agouti locus.

Isolation of transcribed DNA sequences from chromosome 21 using mouse fetal cDNA

A technique for isolating DNA sequences that are likely to be transcriptionally active in both humans and mice has been developed. This method is based on the screening of a human genomic DNA library with single stranded cDNA prepared from late gestation mouse fetal RNA. Using a human chromosome 21 DNA library, we have isolated and characterized two clones which are entirely composed of single copy human DNA sequences and are 2.7 and 6.7 kilobases in length. The 2.7 kilobase clone is homologous to a transcript found predominantly in nonpolyadenylated human fibroblast RNA. It also shows homology to mouse genomic DNA and recognises several polyadenylated RNAs in mouse testis. This cloned sequence has been mapped by in situ hybridization to the distal third of chromosome 21, the region involved in the causation of Down syndrome.

The mouse IFN-alpha (Ifa) locus: correlation of physical and linkage maps by in situ hybridization

The physical location of the mouse IFN-alpha locus (Ifa) on chromosome 4 was defined by in situ hybridization of a cloned mouse IFN-alpha probe to metaphase spreads in which one chromosome 4 was present as part of a single metacentric chromosome, all other chromosomes being acrocentric. (This approach greatly facilitates analysis and can be used even when it is difficult to obtain good banding). Using unbanded chromosomes, the grains were localized over the chromosome 4 part of the metacentric, in a region 0.61 +/- 0.07 (SD) of the distance from the centromere to the telomere. In Giemsa-banded spreads, the majority of the grains were in the region 4C3----C6. Consideration of these results and of the known linkage maps for mouse and man indicates that the Galt - Aco-1 - Ifa syntenic group spans a distance of approximately 14 cM and suggests that the same group on human 9p will also occupy a similarly sized region, with GALT proximal and IFL distal to the centromere.