[Classification, diagnosis and treatment status of pulmonary hypertension from 2012 to 2019: a single center study in Yunnan province]

Objective: To analyze the classification, diagnosis and treatment status of patients with pulmonary hypertension (PH) in Yunnan province. Methods: This was a retrospective study. Hospitalized patients with PH at Yan'an Affiliated Hospital of Kunming Medical University from January 2012 to December 2019 were enrolled. The clinical data of enrolled patients, including demographic data, comorbidities, targeted drug therapy, echocardiography and right heart catheterization results, were obtained through the electronic medical record system. The composition ratio of PH, diagnosis and treatment were analyzed. Results: A total of 13 590 patients with PH were enrolled, accounting for 3.09% (13 590/440 056) of the total number of hospitalizations during the same period. The composition of PH was predominantly pulmonary arterial hypertension (PAH) (55.50% (7 542/13 590)), followed by pulmonary hypertension (PH) caused by left heart disease (24.16% (3 284/13 590)). Among them, PAH could be subdivided into four types: idiopathic pulmonary arterial hypertension (IPAH), PAH associated with connective tissue disease, PAH associated with portal hypertension, and PAH associated with congenital heart disease (CHD-PAH), with CHD-PAH as the predominating type (98.09% (7 398/7 542). Patients with PAH were predominantly adolescents. In hospitalized patients with PH, from 2012 to 2019, the proportion of children and adolescents showed a decreasing trend from year to year, and the proportion of middle-aged and older adults showed a significant increasing trend, and the proportion of female patients showed a gradual decreasing trend, and the proportion of patients with comorbid hypertension, diabetes mellitus, coronary artery disease, arrhythmia, and pneumonia showed an increasing trend. A total of 1 034 patients (7.61% (1 034/13 590)) underwent right heart catheterization. The concordance rate between echocardiographic and right heart catheterization findings was (86.98% (875/1 006)). A total of 2 574 (18.94%) of PH patients were treated with PAH targeted drugs, of which 58.16% (1 497/2 574) were treated with monotherapy. Among the PH patients treated with PAH targeted drugs, the majority of patients were PAH patients (86.44% (2 225/2 574)), and 83.53% (2 150/2 574) patients treated with PAH targeted drugs were CHD-PAH. Conclusions: Hospitalized PH patients in our center between 2012 and 2019 are predominantly CHD-PAH, and the proportion of patients receiving right heart catheterization and targeted drug therapy is relatively low. The percentage of middle-aged and elderly PH patients shows an increasing trend from year to year, as well as the percentage of those with concomitant comorbidities.

Signature of spin-phonon coupling driven charge density wave in a kagome magnet

The intertwining between spin, charge, and lattice degrees of freedom can give rise to unusual macroscopic quantum states, including high-temperature superconductivity and quantum anomalous Hall effects. Recently, a charge density wave (CDW) has been observed in the kagome antiferromagnet FeGe, indicative of possible intertwining physics. An outstanding question is that whether magnetic correlation is fundamental for the spontaneous spatial symmetry breaking orders. Here, utilizing elastic and high-resolution inelastic x-ray scattering, we observe a c-axis superlattice vector that coexists with the 2[Formula: see text]2[Formula: see text]1 CDW vectors in the kagome plane. Most interestingly, between the magnetic and CDW transition temperatures, the phonon dynamical structure factor shows a giant phonon-energy hardening and a substantial phonon linewidth broadening near the c-axis wavevectors, both signaling the spin-phonon coupling. By first principles and model calculations, we show that both the static spin polarization and dynamic spin excitations intertwine with the phonon to drive the spatial symmetry breaking in FeGe.

Construction of ecological security pattern in Ningbo based on remote sensing ecological index and graph theory knowledge

Constructing ecological security pattern and identifying ecological important areas are the focus of current research on regional ecological security. With Ningbo City as a case study area, we identified ecological sources by remote sensing ecological index, the ecological corridors and pinch point by circuit theory model, and the minimum spanning tree and cuts by graph theory algorithm. The results showed that there were 203 ecological sources in Ningbo, and that the main type of land cover was forest, including a small amount of paddy fields and flooded vegetation. There were 368 ecological corridors with a total length of 573.42 km, being dense in the southwest and sparse in the northeast. There were 91 ecological pinch points, which mainly distributed between coastal areas and closely related ecological sources. According to current situation, we put forward the optimization strategy with 187 primary corridors, 181 secondary corridors, 50 ecological restoration priority areas and 59 long-term ecological restoration areas. The optimization strategy combined with graph theory and circuit theory model would provide a refe-rence for the constructing of ecological security pattern.

[Clinical observation of bow-tie adjustable suture technique for overcorrection in intermittent exotropia]

Objective: To investigate the clinical effects of the bow-tie adjustable suture technique in managing overcorrection in patients with intermittent exotropia after surgery. Methods: This was a retrospective case series study. Clinical data were collected from children with intermittent exotropia who underwent strabismus correction surgery, including the bow-tie adjustable suture technique and conventional techniques, at the Department of Strabismus and Pediatric Ophthalmology, Shanxi Eye Hospital, from January 2020 to September 2021. Children with postoperative esodeviation≥15 prism diopters (PD) within the first 6 days were treated differently based on the surgical technique and their individual conditions, including suture adjustment and conservative treatment. The overcorrection rate and its changes among different surgical groups, the recovery of ocular alignment and binocular visual function after different treatment methods in children with overcorrection on the sixth postoperative day, and the postoperative complications in different surgical groups were observed. Statistical analysis was performed using independent samples t-test, Wilcoxon rank-sum test, repeated-measures analysis of variance, Bonferroni test, chi-square test, or Fisher's exact probability test, as appropriate. Results: A total of 643 children who underwent intermittent exotropia correction surgery were included in the study. Among them, 325 children underwent the bow-tie adjustable suture technique, with 185 males and 140 females, and the mean age was (9.50±2.69) years. The remaining 318 children underwent conventional techniques, with 176 males and 142 females, and the mean age was (9.90±2.67) years. There were no statistically significant differences in age and gender distribution between the two surgical groups (all P>0.05). On the first postoperative day, among children who underwent the bow-tie adjustable suture technique, 40 had an esodeviation of≥10 PD, resulting in an overcorrection rate of 12.3% (40/325), while among children who underwent conventional techniques, 32 had an esodeviation of≥10 PD, resulting in an overcorrection rate of 10.1% (32/318). On the sixth postoperative day, these rates decreased to 5.5% (18/325) and 3.1% (10/318) in the two groups, respectively. At 1, 6, and 12 months postoperatively, the overcorrection rate in children who underwent the bow-tie adjustable suture technique was 0, while in children who underwent conventional techniques, the overcorrection rate did not show a significant decrease compared to before surgery. The differences between the two surgical groups were statistically significant (all P<0.05). On the sixth postoperative day, among children with an esodeviation of≥15 PD, 13 underwent suture adjustment and 7 received conservative treatment. The results of repeated-measures analysis of variance showed statistically significant differences in near and distance esodeviation angles among children who received different treatment methods (F=145.20, 106.87, both P<0.001), as well as statistically significant differences in near and distance esodeviation angles at different time points within each group of children (F=81.67, 35.09, both P<0.001). There were also significant differences in the trends of change in near and distance esodeviation angles at different time points among children who received different treatment methods (F=79.90, 36.73, both P<0.001). Further pairwise comparisons showed significant differences in near and distance esodeviation angles between the sixth postoperative day and 1, 6, and 12 months postoperatively in children who underwent suture adjustment (all P<0.05), while no statistically significant differences were observed in children who received conservative treatment (all P>0.05). At 12 months postoperatively, among the 13 children who underwent suture adjustment, 12 achieved stereopsis, while among the 7 children who received conservative treatment, all became stereo-blind after removing the prismatic correction. No serious complications occurred in any of the children postoperatively. Conclusion: The proportion of children with intermittent exotropia who achieved orthotropic alignment one year after surgery was relatively low among those who had an overcorrection of≥15 PD on the sixth postoperative day. The bow-tie adjustable suture technique is a simple and effective approach for managing overcorrection in patients with intermittent exotropia. Adjusting the sutures on the sixth postoperative day can reduce the overcorrection rate and is considered a safe and effective method.

[Femtosecond laser-assisted open astigmatic keratotomy versus non-open astigmatic keratotomy for astigmatism correction in cataract surgery]

Objective: To compare the effects of femtosecond laser-assisted astigmatic keratotomy (FSAK) with and without a manual opening for correction of low to moderate corneal astigmatism at the time of cataract surgery. Methods: It was a prospective cohort study. Patients undergoing cataract surgery from June 2021 to June 2022 at the Army Specialty Medical Center were consecutively enrolled. To correct low to moderate astigmatism, they had combined FSAK with the corneal epithelium manually opened or not according to their own decisions. Pentacam HR corneal topography was performed at 3 months after surgery. The main indicators were target induced astigmatism, surgically induced astigmatism, difference vector, correction index and angle of error. The independent samples t-test was used for continuous variables conforming to a normal distribution, the Mann-Whitney U-test for those not conforming to a normal distribution, and the Chi-square test for categorical variables. Results: There were 51 patients (61 eyes), including 27 patients (31 eyes) receiving combined open FSAK and 24 patients (30 eyes) with non-open keratotomy. No statistical difference was found between the two groups of patients in terms of age, gender and mean follow-up time (P>0.05). The target induced astigmatism was 1.10(0.80, 1.50) D in patients with open keratotomy and 1.30(0.98, 1.73) D in patients with non-open keratotomy (Z=1.729, P=0.084). The surgically induced astigmatism was 0.70 (0.59, 1.25) D and 0.42 (0.20, 0.66) D (Z=-3.571, P<0.001), the difference vector was (0.51±0.31) D and (1.21±0.44) D (t=-7.238, P<0.001), the correction index was 0.78±0.32 and 0.38±0.25 (t=5.386, P<0.001), and the angle of error was -1.08°±10.76° and 5.93°±46.98° (t=0.809, P=0.422) in the two groups, respectively. Conclusion: Open FSAK can achieve better astigmatism correction and less postoperative residual astigmatism than non-open FSAK in cataract surgery.

[Pathological characteristics and clinical prognosis of nodular sclerosis grade 2 of classic Hodgkin's lymphoma]

Objective: To investigate the pathological characteristics and clinical prognosis of nodular sclerosis grade 2 of classic Hodgkin's lymphoma (cHL-NS2) in our cancer center. Methods: A retrospective collection of 23 cases of cHL-NS2 admitted in Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College from July 2008 to April 2019 was performed. Fifty-five cases of nodular sclerosis grade 1 of classical Hodgkin's lymphoma (cHL-NS1) during the same period were selected as control group. Survival curves were plotted using the Kaplan-Meier method, and Cox regression model was used to analyze the influencing factors for survival. Results: The median age of 23 cases of cHL-NS2 was 30 years old. Five cases had extra nodal invasion, and 19 cases were Ⅰ-Ⅱ stage based on Ann Arbor system. The pathological morphology of cHL-NS2 showed that the lymph node structure was completely destroyed and was divided into nodules by thick collagen. The tumor cells in the nodules were abundant and proliferated in sheets. The boundaries between the tumor cells were not clear. The incidence of tumor necrosis in cHL-NS2 was 43.5% (10/23), which was significantly higher than 18.2% (10/55) in cHL-NS1 (P=0.040). The 3-year progression-free survival (PFS) rate of patients in the cHL-NS2 group was 58.1%, which was significantly lower than 89.7% in the cHL-NS1 group (P=0.002). In all of 78 cases, the 3-year PFS rate of patients who did not obtain complete response (CR) was 67.1%, which was significantly lower than 92.2% in patients who achieved CR (P=0.030). Multivariate Cox regression analysis demonstrated that both cHL-NS2 and failure to obtain CR by first-line treatment were independent indicators for short PFS time (P<0.05). Conclusions: In cHL-NS2, the morphology of tumor cells are diverse, and tumor necrosis can be easily found. Under the current first-line treatments of doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD) or bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, and prednisone (BEACOPP), cHL-NS2 is an independent indicator for worse PFS.

[Short-term outcomes of prism treatment in a manner of reducing prism diopters step by step for small-angle acute acquired concomitant esotropia]

Objective: To investigate the short-term efficacy of the prism treatment in a manner of reducing prism diopters step by step for small-angle acute acquired concomitant esotropia (AACE). Methods: Retrospective case series study. The clinical data of 17 AACE patients with strabismus ≤25 prism degrees (PD) including 6 males and 11 females, aged 14 to 60 years, who underwent the prism treatment in the Strabismus and Pediatric Ophthalmology Clinic of Shanxi Eye Hospital from October 2018 to June 2020 were collected. The prism treatment was conducted by a step-by-step reduction of prism diopters. An under-corrected prism was applied to the patient for the first time, and the degree of the prism was reduced gradually with the decrease in the degree of strabismus. Statistical analysis was performed after 6 months of treatment. The treatment success was defined as obtaining orthotropia and deleting diplopia when prism glasses were weaned off. The strabismus degree, Worth 4 dot test results, near stereopsis (Titmus stereopsis) and synoptophore fusion function before and after treatment were compared, and the factors affecting the curative effect were analyzed. Statistical methods mainly included paired t-test, Wilcoxon rank sum test, the Fisher exact test and univariate logistic regression analysis. Results: Among these 17 patients, 15 had myopia and 2 had emmetropia. Pretherapeutic esodeviation was (13.94±5.83) PD at near (33 cm), and was (15.76±5.24) PD at distance (6 m). After 6 months of treatment, 7 patients were successfully cured. The deviation angle at distance [(10.60±7.16) PD] and near [(9.80±6.00) PD] of the remaining 10 patients at 6 months after prismatic treatment was significantly smaller than that before treatment [(17.50±5.40) PD and (16.10±5.47) PD; t=3.69, 4.10; both P<0.01]. The Titmus stereogram showed that 2 cases had no stereopsis, 6 cases had peripheral stereopsis, 3 cases had macular stereopsis, and 6 cases had foveal stereopsis before treatment. Stereopsis was significantly improved at 6 months after prismatic treatment, with 3 cases havimg macular stereopsis and 14 cases having foveal stereopsis (Z=-2.99; P<0.01). The Worth-4-dot test disclosed that, the number of patients who saw four lamps at distance and near was 0 and 2 before treatment, and 7 and 9 after treatment, respectively, and the difference was statistically significant (both P<0.05). The divergent fusional amplitude and convergent fusional amplitude in the synoptophore at 6 month after treatment was not significantly different from that before treatment (both P>0.05). The efficacy of treatment was not significantly related to the duration from onset to treatment, the pretherapeutic esodeviation, the Titmus stereoacuity, cycloplegic refractive error, and age (all P>0.05). None of the 7 patients, who were successfully cured had a recurrence of esotropia or diplopia during the observation period of 6 to 24 months (median, 11 months). Conclusions: Prism treatment in a manner of step-by-step reduction of prism diopters can significantly diminish the degree of esotropia and improve the binocular function in small-angle AACE. Furthermore, some patients could be cured, achieving orthophoria without diplopia.

[Clinical characteristics of patients with acute pulmonary embolism in high altitude area of Yunnan province in China]

Objective: To analyze the clinical features of patients with acute pulmonary embolism (APE) living in high altitude area of Yunnan province. Methods: This was a cross-sectional retrospective study. APE patients, hospitalized in our hospital between January 2017 and December 2019, were included. The selected patients were divided into low-risk group, medium-risk group and high-risk group according to risk stratification. The clinical data of patients, including demographic data, the main symptoms, risk factors of APE, heart rate and systolic blood pressure and laboratory testing results (D-dimer, cardiac troponin I (cTNI), N terminal B-type natriuretic peptide (NT-proBNP)) and echocardiography and electrocardiogram examination results, were obtained through the electronic medical record system. The clinical characteristics of selected patients were analyzed. Results: A total of 392 patients, aged (63.5±15.7) years, 224 males (57.14%), were included in this study and there were 59 low-risk, 304 medium-risk and 29 high-risk patients in this cohort. The main clinical manifestations were chest pain (157(40.05%)), dyspnea (107(27.30%)), hemoptysis (55(14.03%)), syncope as the first symptom (20(5.10%)), and only 6 cases (1.53%) presented with the typical "Virchow's triad". Most of the patients were accompanied by atypical chest tightness (223(56.89%)) and cough (208(53.06%)). The main risk factors were venous thrombosis of lower limbs (179(45.66%)), hypertension (138(35.20%)), surgery (63(16.07%)), and chronic obstructive pulmonary disease (COPD) (62(15.82%)). There were 57 cases (14.54%) of coronary heart disease, 57 cases (14.54%) of diabetes, 51 cases (13.01%) of cerebral infarction, 47 cases (12.00%) of advanced age, 15 cases (3.83%) of tumor, 7 cases (1.79%) of activity restriction, 6 cases (1.53%) of pregnancy and 4 cases (1.02%) of hormone use in this cohort. The proportion of lower extremity venous thrombosis was significantly higher in low-risk group than in medium-risk group (P<0.01), COPD was more common in high-risk and medium-risk groups than in low-risk group (P<0.01), hypertension was more common in high-risk group than in medium-and low-risk groups (P<0.01). The proportion of advanced age was significantly higher in medium-risk group than in low-risk group (P<0.01). There were no significant differences in RBC and hemoglobin level between low-, medium-and high-risk groups (P>0.05). The level of D-dimer was significantly higher in high-risk group than in medium-and low-risk groups (P<0.05). Levels of NT-proBNP and cTNI were significantly higher in high-risk group than in medium- and low-risk groups (P<0.05). Increased proportion of cTNI and NT-proBNP was significantly higher in high-risk group than in medium- and low-risk groups (P<0.05). There were 105 (26.79%) patients with pulmonary hypertension (PAH). The incidence of PAH was significantly higher in high-risk group than in low-risk group (P<0.01). There were 104 patients (26.53%) with right ventricular enlargement, and the incidence of right ventricular enlargement was significantly higher in high-risk group than in medium-and low-risk groups (P<0.01). Characteristic changes of electrocardiogram in patient with APE were T-wave inversion of limb leads (98(25.00%)), followed by S_ⅠQ_ⅢT_Ⅲ (83(21.17%)). Conclusions: The main clinical manifestations of APE in Yunnan high altitude area are chest pain and dyspnea, and syncope is the first symptom in some patients, but the typical "Virchow's triad" is rare. The most common risk factors are lower extremity venous thrombosis, hypertension, and COPD. Clinical symptoms, risk factors and laboratory examination results differ among patients with different risk stratification.

The complete chloroplast genome sequence of Clivia robusta

In this study, we reported the complete chloroplast genome sequence of Clivia robusta for the first time. The complete chloroplast genome of C. robusta was 157,130 bp in length, containing a large single-copy region (LSC, 85,430 bp), a small single-copy region (SSC, 18,278 bp), and two inverted repeat regions (IRs, 26,711 bp). The overall GC content was 38.01%. The chloroplast genome contained 128 genes in total, including 86 protein-coding, 34 tRNA, and eight rRNA genes. The phylogenetic tree showed that C. robusta formed a monophyletic clade with other Clivia species.

The complete chloroplast genome sequence of Clivia miniata var. citrina

The complete chloroplast genome of Clivia miniata var. citrina was assembled and subjected to phylogenetic analysis in this study. The complete chloroplast genome of C. miniata var. citrina was 158,112 bp in length, containing a large single-copy region (LSC, 86,202 bp), a small single-copy region (SSC, 18,334 bp), and two inverted repeat regions (IRs, 26,788 bp). The GC content was 37.97%. A total of 130 genes were annotated, including 86 protein-coding genes, 36 tRNA and 8 rRNA genes. Phylogenetic analysis showed that C. miniata var. citrina was the most related with C. miniata and they formed a monophyletic group that was sister to the clade of Hippeastrum, Leucojum, Narcissus and Lysoris.

The complete chloroplast genome sequence of Clivia caulescens

Clivia caulescens is an evergreen herbaceous flower with high ornamental value. In this study, we report its complete chloroplast genome sequence. The whole chloroplast genome was 158,149 bp in length, with a large single copy region (LSC, 86,250 bp), a small single copy region (SSC, 18,343 bp), and two inverted repeat regions (IRs, 26,778 bp). The overall GC content was 37.91%. There were 128 genes annotated, including 86 protein-coding genes, 34 tRNA genes, and eight rRNA genes. The phylogenetic tree showed that C. caulescens formed a monophyletic clade with C. miniata, C. miniata var. aurea, and C. gardenii.

The immunomodulatory peptide bursopentin (BP5) enhances proliferation and induces sIgM expression in DT40 cells

BACKGROUND

In the recent past, many studies have been focused on extracts of BF and multiple biologically active factors and their effects on humoral immune system in chickens and birds. However, the mechanism of those immunomodulatory peptides on the B lineage cells proliferation and antibody production in chicken is fairly unknown. DT40 cell line, an avian leucosis virus-induced chicken pre-B cell line, expresses immunoglobulin M (IgM) isotype B cell reporter in the plasma membrane. There are many evidences suggesting that DT40 cells are best characterized as a bursal stem cell line. Because of the unique characteristics of DT40 cell line, it has been widely used to observe biological processes of pre-B lymphocyte cell within living cells.

METHODS

The chicken B cell line DT40 was cultured in Roswell Park Memorial Institute (RPMI) 1640 medium and cytotoxicity was studied. Also, effect of BP5 on cell proliferation and cell cycle distribution of DT40 cells was studied. Also, the effect of BP5 on sIgM mRNA expression was studied by using real-time PCR.

OBJECTIVES

To investigat the effects of Bursopentin (Cys-Lys-Arg-Val-Tyr, BP5) on a chicken promyelocyte cell line DT40, assays of cell proliferation, cell cycle distribution, detection of surface immunoglobulin G (sIgM) mRNA expression and gene microarray analysis were performed.

RESULTS

The results showed that BP5 displayed concentration-dependent effects on the proliferation, cell cycle, and sIgM mRNA expression in DT40 cells. And the analysis of expression profiles identified a signature set of 3022 genes (1254 up regulated genes, 1762 down regulated genes), which clearly discriminated the BP5-treated DT40 cells from control with high certainty (P≤0.02). The results of microarray analysis were confirmed by quantitative reverse transcription-polymerase chain reaction for 12 of the differentially expressed genes.

CONCLUSION

Theses findings showed the immuno-activity effect of BP5 on B lymphocyte and indicated that BP5 treatment regulated eight signaling pathways, in which Toll-like signaling pathway was the most significant enrichment pathway.

[Effects of pretreatment with dimethyloxalylglycine on the survival of multi-territory perforator flap in rat and related mechanism]

OBJECTIVE

To observe the effects of pretreatment with dimethyloxalylglycine (DMOG) on the survival of multi-territory perforator flap and the vessels of choke zone (CZ) 2 in rat, and to explore related mechanism.

METHODS

Sixty adult SD rats were divided into group DMOG and normal saline group (NS) according to the random number table, with 30 rats in each group. Perforator flap with three angiosomes was made on the right dorsal side of rat, including deep iliac circumflex artery perforator, intercostal artery perforator, thoracodorsal artery perforator, as well as CZ 1 and CZ 2. Rats in group DMOG were intraperitoneally injected with 2 mL NS containing DMOG (40 mg/kg) 2 days before operation, 2 hours before operation, and 2 days after operation. Rats in group NS were intraperitoneally injected with equivalent volume of NS at the same time point. On post operation day (POD) 7, gross observation was conducted, and the survival rate of flap was calculated. On POD 7, the vascularity in CZ 2 and potential zone of flap was observed using angiography. On POD 7, new vessel in CZ 2 of flap was observed with HE staining, and the microvessel density (MVD) was calculated. On POD 7, the expression of vascular endothelial growth factor (VEGF) in CZ 2 of flap was detected by immunohistochemistry and Western blotting (respectively denoted as integral absorbance values and ratio of gray value), and blood flow volume of vessel in CZ 2 of flap was examined by laser Doppler perfusion imager. The sample number of each index was 6 in each group. Data were processed with t test.

RESULTS

(1) On POD 7, rats in two groups all survived, and the flaps were not infected. In group DMOG, the necrotic area of flaps of rats with dark yellow crust and soft texture was observed approximately at the distal end of skin entry point of thoracodorsal artery perforator. In group NS, the necrotic area of flaps of rats with brownish black crust and hard texture was observed approximately at the distal end of CZ 2. The survival rate of flap of rats in group DMOG was (88±3) %, which was significantly higher than that in group NS [(82±3) %, t=3.38, P<0.01]. (2) On POD 7, there were clear vascular structure and many new vessels in CZ 2 of flaps of rats in group DMOG, with intact vascular structure in potential zone. On POD 7, there were unclear vascular structure and few new vessels in CZ 2 of flaps of rats in group NS, with disorder vascular structure in potential zone. (3) On POD 7, MVD in CZ 2 of flaps in rats of group DMOG was (29.2±2.2)/mm(2,) which was significantly higher than that of group NS [(20.3±3.6)/mm(2,) t=5.10, P<0.01]. (4) On POD 7, the expressions of VEGF in CZ 2 of flaps in rats of group DMOG detected by immunohistochemistry and Western blotting were 5 060±432 and 0.48±0.04 respectively, which were significantly higher than those of group NS (2 811±382 and 0.26±0.06, with t values respectively 9.54 and 5.67, P values below 0.01). (5) On POD 7, blood flow volume of vessel in CZ 2 of flaps in rats of group DMOG was (58±4) perfusion units (PU), which was significantly more than that of group NS [(46±4) PU, t=5.20, P<0.01].

CONCLUSIONS

DMOG can increase the survival rate of multi-territory perforator flap through promoting angiogenesis in CZ 2 of flap on the back of rat and improving blood supply of flap.

Superconductivity in HfTe5 across weak to strong topological insulator transition induced via pressures

Recently, theoretical studies show that layered HfTe₅ is at the boundary of weak & strong topological insulator (TI) and might crossover to a Dirac semimetal state by changing lattice parameters. The topological properties of 3D stacked HfTe₅ are expected hence to be sensitive to pressures tuning. Here, we report pressure induced phase evolution in both electronic & crystal structures for HfTe₅ with a culmination of pressure induced superconductivity. Our experiments indicated that the temperature for anomaly resistance peak (Tp) due to Lifshitz transition decreases first before climbs up to a maximum with pressure while the Tp minimum corresponds to the transition from a weak TI to strong TI. The HfTe₅ crystal becomes superconductive above ~5.5 GPa where the Tp reaches maximum. The highest superconducting transition temperature (Tc) around 5 K was achieved at 20 GPa. Crystal structure studies indicate that HfTe₅ transforms from a Cmcm phase across a monoclinic C2/m phase then to a P-1 phase with increasing pressure. Based on transport, structure studies a comprehensive phase diagram of HfTe₅ is constructed as function of pressure. The work provides valuable experimental insights into the evolution on how to proceed from a weak TI precursor across a strong TI to superconductors.

[Molecular diagnosis of two Chinese cystic fibrosis children and literature review]

OBJECTIVE

To investigate the clinical manifestations and molecular features of cystic fibrosis in Chinese children.

METHOD

A retrospective analysis of two pediatric cystic fibrosis cases diagnosed by gene test in Beijing Children's Hospital, Capital Medical University from 2010 to 2015, and Chinese cystic fibrosis reported patients searched of"cystic fibrosis, Chinese"on Chinese databases (CNKI, Wanfang Data) and PubMed from 1975 to 2015.The clinical manifestations and molecular features were analyzed.

RESULT

One of the two newly diagnosed cystic fibrosis cases was a 10-year old girl who suffered from reccurent cough with expectoration and associated with cirrhosis.Sweat tests showed increased chloride twice with the lower level of 306.82 mmol/L.The other was an 8-month old boy with reccurent pneumonia from neonate, failure to thrive and fatty diarrhea.Two children had various degrees of bronchiectasis and massive sticky secretion on the bronchoscopy.They had no family history and their parents had no consanguineous marriage.CFTR mutations of c. 595C>T and c. 2290C>T were found in gene tests.On the database, twenty-one reports involving thirty-six Chinese patients (16 males and 20 females) were retrieved.Together with this group of 2 cases, a total of 38 cases were involved.The age at diagnosis was 4 months to 28 years with a median age of 10 years.All patients had reccurent respiratory infections, twenty-seven cases (71%) had malnutrition, fifteen (39%)had chronic diarrhea, and 16 cases (42%) had other digestive manifestations, including jaundice (4 cases), hepatomegaly (11 cases), ascites (2 cases) and pancreatic atrophy (3 cases). Five cases had a positive family history and six cases had a suspicious family history.Consanguineous marriage was found in three families.Sweat test revealed elevated chloride (52-327 mmol/L) in 28 cases.Eight of the 16 patients who performed pancreatic exocrine function examination showed pancreatic insufficiency.Eighteen of the 20 patients described the image manifestation of bronchiectasis.The age at death of 13 patients(34%) was 4 months to 25 years with a median of 11 years.Twenty-nine rare CFTR mutations were found in 25 tested patients, and c. 1766+ 5G>T(5 cases), c.2083dupG and c. 2684G>A (3 cases) held the top three mutation patterns.

CONCLUSION

Respiratory symptoms and bronchiectasis are the main manifestations of Chinese cystic fibrosis patients, although some of them may be associated with malnutrition, digestive symptoms and pancreatic insufficiency. CFTR mutations are various and rare in Caucasians.

Amino acid composition of royal jelly harvested at different times after larval transfer

The amino acids in royal jelly (RJ) have a wide range of pharmacological and health-promoting functions in humans. Multiple studies on the amino acid quality and composition in RJ have investigated RJ harvested at 72 h after larval transfer. In contrast, the concentration of amino acids in RJ harvested before 72 h remains unknown. In this study, the concentration of free amino acids (FAAs) and total amino acids (TAAs) in RJ harvested at 13 time points between 24 and 72 h after transfer of ten Apis mellifera colonies were measured. Our results indicated that the most abundant FAAs were Pro, Phe, Lys, Glu, and Tyr, whereas the most abundant TAAs were Asp, Glu, Leu, Lys, and Val. The total FAA concentration in RJ increased with increasing harvest time, from 4.30 mg/g at 24 h to 9.48 mg/g at 72 h. In contrast, the variation in concentration of TAAs observed was a decrease-increase-decrease trend with 40 h (149.53 mg/g) and 52 h (169.62 mg/g) as inflection points. The highest and lowest concentrations of TAA were 197.96 and 121.32 mg/g at 24 and 72 h, respectively. To our knowledge, this is the first study to investigate the concentration changes of FAAs and TAAs prior to 72 h after transfer. Our results will provide theoretical support to guide production practices of beekeeping, as well as elucidate the relationship between the harvest time point and RJ content.

[Association between β-arrestin2 genetic polymorphism and response to methadone maintenance treatment in heroin-dependent patients in Han population in Hunan province]

OBJECTIVE

To study the distributions of three single nucleotide polymorphisms (SNPs) in β-arrestin2 (ARRB2) which including rs3786047, rs1045280 and rs2036657 and to elucidate the relationship between these SNPs and response to methadone maintenance treatment (MMT) among heroin-dependent patients of Han ethnicity population in Hunan.

METHODS

Han MMT patients were recruited in four random-chosen MMT clinics from Hunan province. Demographics, history of drug-use and MMT were recorded. ARRB2 SNPs were genotyped to determine the association between SNPs and response to MMT.

RESULTS

Distributions of the three SNPs were in Hardy-Weinberg equilibrium in both groups (responders vs. non-responders). There was no statistical significance in the distribution frequency of genotype on rs3786047 (χ(2)=0.486 2, P=0.784), rs1045280 (χ(2)=1.591 9, P=0.451) and rs2036657 (χ(2)=1.061 5, P=0.588) in ARRB2 among the responders or the non-responders.

CONCLUSION

Associations between the ARRB2 genotypes, rs3786047, rs1045280 and rs2036657, and MMT response in Han MMT patients in Hunan province did not appear.

Molecular cloning and evolutionary analysis of captive forest musk deer bitter taste receptor gene T2R16

Sensing bitter tastes is crucial for most animals because it can prevent them from ingesting harmful food. This process is mainly mediated by the bitter taste receptors (T2R) that are largely expressed in the taste buds. Previous studies have identified some T2R gene repertoires. Marked variation in repertoire size has been noted among species. However, research on T2Rs is still limited and the mechanisms underlying the evolution of vertebrate T2Rs remain poorly understood. In the present study, we analyzed the structure and features of the protein encoded by the forest musk deer (Moschus berezovskii) T2R16 and submitted the gene sequence to NCBI GenBank. The results showed that the full coding DNA sequence (CDS) of musk deer T2R16 (GenBank accession No. KP677279) was 906 bp, encoding 301 amino acids, which contained ATG start codon and TGA stop codon, with a calculated molecular weight of 35.03 kDa and an isoelectric point of 9.56. The T2R16 protein receptor had seven conserved transmembrane regions. Hydrophobicity analysis showed that most amino acid residues in T2R16 protein were hydrophobic, and the grand average of hydrophobicity (GRAVY) was 0.657. Phylogenetic analysis based on this gene revealed that forest musk deer had the closest association with sheep (Ovis aries), as compared to cow (Bos taurus), Tursiops truncatus, and other species, whereas it was genetically farthest from humans (Homo sapiens). We hope these results would complement the existing data on T2R16 and encourage further research in this respect.

Association of IL-1, IL-18, and IL-33 gene polymorphisms with late-onset Alzheimer׳s disease in a Hunan Han Chinese population

Interleukin (IL)-1 plays an important role in Alzheimer׳s disease (AD), and single nucleotide polymorphisms (SNPs) in the IL-1 gene have been shown to be associated with AD susceptibility. IL-18 and IL-33 are proinflammatory cytokines of the IL-1 family, and increasing evidence has accumulated to support their crucial role in AD pathogenesis. To examine whether SNPs in IL-1α (rs1800587), IL-1β (rs1143627), IL-18 (rs187238), and IL-33 (rs11792633) are associated with late-onset Alzheimer׳s disease (LOAD) in a Hunan Han Chinese population, we carried out a case-control study involving 201 LOAD patients and 257 healthy controls. No significant differences were found in genotype frequencies of rs1800587 between LOAD patients and controls (P=0.079), but the T allele of rs1800587 was associated with a significantly increased risk of LOAD (P=0.032, odds ratio (OR)=1.592). Significant differences in genotype (P=0.004) and allele (P=0.001) frequencies of rs11792633 were found between LOAD patients and controls, but not for rs1143627 (P=0.535, 0.262, respectively) or rs187238 (P=0.257, 0.139, respectively). The T allele of rs11792633 was found to be a protective factor for LOAD (OR=0.648). These findings suggest that the IL-1α SNP rs1800587 and IL-33 SNP rs11792633, but not the IL-1β SNP rs1143627 or the IL-18 SNP rs187238, contribute to LOAD susceptibility in the Hunan Han Chinese population. This article is part of a Special Issue entitled SI: Brain and Memory.

Effect of sonication on B cell development and immunomodulatory functions of Bursa of Fabricius

A study was initiated with the objective of evaluating the effects of sonication treatment on important quality parameters of extract of Bursa of Fabricius. Sonication of extract was done (frequency 20 kHz and various amplitude levels) at 0 °C for 10 min, 30 min, 50 min, respectively. As results, the yield of bursa peptides significantly increased (p<0.05). Then we found sonicated bursa extract promoted the content of bursin and the CFU pre-B formation, exerted immunomodulatory function on antigen-specific immune responses in C57/BL6 mice immunized with inactivated Japanese encephalitis b virus (JEV) vaccine, including enhancing JEV-specific antibody and cytokine production, T-cell immunophenotyping and lymphocyte proliferation. Findings of the present study suggested the sonication treatment of Bursa of Fabricius could improve the yield as well as the quality of bursa peptides, indicating that sonication is effective in processing of bursa extract and could be a potential process for future immuno-pharmacological use.

Comparison of immunomodulatory functions of three peptides from the chicken bursa of Fabricius

The bursa of Fabricius (BF) is the acknowledged central humoral immune organ unique to birds which plays important roles in B cell development and antibody production. Little information on immunomodulatory functions of BF is reported, except for several reported active bursal-derived peptides. Three peptides were identified and characterized from BF through RP-HPLC and MADIL-TOF methods. They are named as bursal peptide (BP)-I, BP-II, BP-III. These peptides promoted CFU pre-B formation and decreased PU.1 expression. The different immunomodulatory activities of these three bursal peptides on antibody and cytokine productions were verified by the immunization comparative experiment. The results showed the three bursal peptides enhanced AIV-specific antibody and cytokine production, T-cell immunophenotyping at reachable concentrations. These results indicate the important orientations for the comprehensive understanding of the humoral central immune system, and provide a novel insight on new experimental reagents for immuno-adjuvant or immunopharmacological.

Immunomodulatory roles and functional analysis of pre-B lymphocyte DT40 cells with the bursal-derived BSP-II treatment

The bursa of Fabricius, the acknowledged central humoral immune organ, is vital to B cell differentiation. However, the regulatory function of the bursal-derived peptide on avian B cell proliferation has not been reported. BSP-II is a recently reported bursal-derived bioactive peptide. In this paper, 75 days-old chicks were twice subcutaneously immunized with BSP-II and inactivated avian influenza virus (AIV, H(9)N(2) strain). It was proved that BSP-II induced a strongly AIV-specific HI antibody production in the immunized chicks. Also, BSP-II could enhance avian pre-B lymphocyte DT40 cell viability. To investigate the global patterns of gene expression in DT40 cells after BSP-II treatment, gene microarray was carried out. It was identified that the differentially expressed genes were involved in various pathways, of which six pathways were associated with signaling transductions, including ErbB signaling, MAPK signaling, Toll-like receptor signaling, Notch signaling, mTOR signaling, and Wnt signaling. Finally, RT-qPCR was used to confirm the microarray expression data. These results indicated the molecular basis of pre-B lymphocyte viability with BSP-II treatment, which provided a potential mechanism of the bursa of Fabricius on pre-B lymphocyte viability, differentiation, and development. These results are valid for the mechanism of the bursa of Fabricius on B lymphocytes development.

Isolation, modulatory functions on murine B cell development and antigen-specific immune responses of BP11, a novel peptide from the chicken bursa of Fabricius

The bursa of Fabricius (BF) is the central humoral immune organ unique to birds which plays important roles in B lymphocyte differentiation. Here, a new bursal peptide (BP11) with the amino acid sequence DVAGKLPDNRT was identified and characterized from BF. It was proved that BP11 promoted CFU pre-B formation, and regulated B cell differentiation, including increase the percentage of immature and mature B cells in BM cells co-cultured with IL-7. BP11 also exerted immunomodulatory function on antigen-specific immune responses in BALB/c mice immunized with inactivated influence virus (AIV, H9N2 subtype) vaccine, including enhancing AIV-specific antibody and cytokine production. Furthermore, it was noteworthy that BP11 stimulated antibody productions and potentiates the Th1 and Th2-type immune responses in dose-dependent manner in chicken. These results suggested that BP11 might be highly relevant for the development of avian immune system.

Strongly interacting photons in asymmetric quantum well via resonant tunneling

We propose an asymmetric quantum well structure to realize strong interaction between two slow optical pulses. The essential idea is the combination of the advantages of inverted-Y type scheme and resonant tunneling. We analytically demonstrate that giant cross-Kerr nonlinearity can be achieved with vanishing absorptions. Owing to resonant tunneling, the contributions of the probe and signal cross-Kerr nonlinearities to total nonlinear phase shift vary from destructive to constrictive, leading to nonlinear phase shift on order of π at low light level. In this structure, the scheme is inherent symmetric for the probe and signal pulses. Consequently, the condition of group velocity matching can be fulfilled with appropriate initial electron distribution.

Characterization and immunomodulatory function comparison of various bursal-derived peptides isolated from the humoral central immune organ

The bursa of Fabricius (BF) is the acknowledged central immune organ, which is important to the B cell differentiation and antibody production. However, due to difficult purification, the immunomodulatory peptides from BF were little reported. In this study, the extract samples of BF were taken to a chromatographic analysis by RP-HPLC. Five novel low molecular weight peptides were isolated from BF, with amino acid sequences of YEYAY, RMYEE, GPPAT, AGCCNG, and RRL, and named as Bursal pentapeptide (BPP)-III, -IV, -V, and Bursal hexapeptide (BHP), and Bursal tripeptide (BTP), respectively. BSP-I, BSP-II, BPP-I and BPP-II are recently reported to be the bursal-derived bioactive peptides. In this paper, we analyzed the chemical formula and characteristics of these nine bursal-derived peptides. The immunization comparative experiment verified the different immunomodulatory activity of these nine bursal peptides on antibody and cytokine productions. Furthermore, the results showed that at reachable concentrations, BPP-II and BPP-I induced antibody productions, lymphocyte viabilities and cytokine responses in different dose-dependent manner in the immunized mice model, respectively. These results provided important orientations for the comprehensively understanding and study of the humoral central immune system of human, and provided a novel insight on the treatment of serious disease and immune improvement of human.

Identification and characterization of novel immunomodulatory bursal-derived pentapeptide-II (BPP-II)

The bursa of Fabricius, the acknowledged central humoral immune organ, plays a vital role in B lymphocyte differentiation. However, there are few reports of the molecular basis of the mechanism on immune induction and potential antitumor activity of bursal-derived peptides. In this paper, a novel bursal-derived pentapeptide-II (BPP-II, MTLTG) was isolated and exerted immunomodulatory functions on antibody responses in vitro. Gene microarray analyses demonstrated that BPP-II regulated expression of 2478 genes in a mouse-derived hybridoma cell line. Immune-related gene ontology functional procedures were employed for further functional analysis. Furthermore, the majority of BPP-II-regulated pathways were associated with immune responses and tumor processes. Moreover, BPP-II exhibited immunomodulatory effects on antigen-specific immune responses in vivo, including enhancement of avian influenza virus (H9N2 subtype)-specific antibody and cytokine production and modification of T cell immunophenotypes and lymphocyte proliferation. Finally, BPP-II triggered p53 expression and stabilization and selectively inhibited tumor cell proliferation. These data identified the multifunctional factor, BPP-II, as a novel biomaterial representing an important linking between the humoral central immune system and immune induction, including antitumor. Information generated in this study elucidates further the mechanisms involved in humoral immune system and represents the potential basis of effective immunotherapeutic strategies for treating human tumors and immune improvement.

Socio-economic disparities in maternal mortality in China between 1996 and 2006

OBJECTIVE

China's economic reforms have raised concerns over rising inequalities in maternal mortality, but it is not known whether the gap across socio-economic regions has increased over time.

DESIGN

A population-based, longitudinal, ecological correlation study.

SETTING

China.

SAMPLE

Records from the National Maternal and Child Mortality Surveillance System between 1996 and 2006.

METHODS

We report levels, causes and timing of maternal deaths, and examine crude and adjusted time trends in the overall and cause-specific maternal mortality ratio in five socio-economic regions (using Poisson regression). We examine whether socio-economic disparities have widened over time using concentration curves.

MAIN OUTCOME MEASURES

All-causes and cause-specific maternal mortality ratios.

RESULTS

Maternal mortality (MMR) declined by 6% per year (yearly rate ratio, RR, 0.94; 95% CI 0.93-0.96). The decline was most pronounced in the wealthiest rural type-I counties (RR 0.89; 95% CI 0.85-0.93), and in the poorest rural type-IV counties (RR 0.90; 95% CI 0.82-1.00). There were declines in almost all causes of maternal death. Postpartum haemorrhage (PPH) was by far the leading cause of maternal death (32%, 997/3164). The decline in MMR was largely explained by the increased uptake of institutional births. Concentration curves suggest that wealth-related regional inequalities did not increase over time.

CONCLUSIONS

China's extraordinary economic growth has not adversely affected disparities in MMR across socio-economic regions over time, but poor rural women remain at disproportionate risk. Other emerging economies can learn from China's focus on the supply and quality of maternity services along with more general health systems strengthening.

Low voltage nanoelectromechanical switches based on silicon carbide nanowires

We report experimental demonstrations of electrostatically actuated, contact-mode nanoelectromechanical switches based on very thin silicon carbide (SiC) nanowires (NWs). These NWs are lithographically patterned from a 50 nm thick SiC layer heteroepitaxially grown on single-crystal silicon (Si). Several generic designs of in-plane electrostatic SiC NW switches have been realized, with NW widths as small as approximately 20 nm and lateral switching gaps as narrow as approximately 10 nm. Very low switch-on voltages are obtained, from a few volts down to approximately 1 V level. Two-terminal, contact-mode "hot" switching with high on/off ratios (>10(2) or 10(3)) has been demonstrated repeatedly for many devices. We find enhanced switching performance in bare SiC NWs, with lifetimes exceeding those based on metallized SiC NWs.

Parametric nanomechanical amplification at very high frequency

Parametric resonance and amplification are important in both fundamental physics and technological applications. Here we report very high frequency (VHF) parametric resonators and mechanical-domain amplifiers based on nanoelectromechanical systems (NEMS). Compound mechanical nanostructures patterned by multilayer, top-down nanofabrication are read out by a novel scheme that parametrically modulates longitudinal stress in doubly clamped beam NEMS resonators. Parametric pumping and signal amplification are demonstrated for VHF resonators up to approximately 130 MHz and provide useful enhancement of both resonance signal amplitude and quality factor. We find that Joule heating and reduced thermal conductance in these nanostructures ultimately impose an upper limit to device performance. We develop a theoretical model to account for both the parametric response and nonequilibrium thermal transport in these composite nanostructures. The results closely conform to our experimental observations, elucidate the frequency and threshold-voltage scaling in parametric VHF NEMS resonators and sensors, and establish the ultimate sensitivity limits of this approach.

Variability of total and available copper concentrations in relation to land use and soil properties in Yangtze River Delta of China

The effects of land use and soil properties on total and available Cu concentrations in soils were investigated in this study. A total of 276 surface (0-20 cm) soil samples were collected from seven land uses: industrial area, woodland, vegetable field, dry land, paddy field, tea garden and orchard. The total and available (DTPA extractable) Cu concentrations, pH, organic matter, and total nitrogen contents, and cation exchange capacity were measured for each sample. The correlation and ANOVA analyses showed that land use significantly affected total and available Cu concentrations, and the available ratio of soil Cu (available Cu concentration/total Cu concentration). On total Cu concentration, total nitrogen had significant influence in dry land and paddy field, and CEC in garden land; on available Cu concentration, the four measured soil properties showed significant influence only in paddy field; on the available ratio of Cu, pH had significant effect in paddy field and woodland, and CEC in industrial area. Moreover, the relationship between available Cu concentration and soil properties was constructed in different land uses. Spatial analysis of grain Cu using indicator Kriging showed that most of the study areas were in low risk for arable activities, and 7.94% of the study area and 5.10% of the arable land were in high risk probability.

Identification of soil heavy metal sources from anthropogenic activities and pollution assessment of Fuyang County, China

Understanding regional variations of soil heavy metals and their anthropogenic influence are very important for environmental planning. In this study, 286 surface soil samples were collected in Fuyang county, and the 'total' metals for copper (Cu), zinc (Zn), lead (Pb), cadmium (Cd) and nickel (Ni) were measured in 2005. Statistic analysis showed that Cu, Zn, Pb and Cd had been added by exterior factors, and Ni was mainly controlled by natural factors. The combination of multivariate statistical and geostatistical analysis successfully grouped three groups (Cu, Zn and Pb; Cd; and Ni) of heavy metals from different sources. Through pollution evaluation, it was found that 15.76% of the study area for Cu, Zn and Pb, and 46.14% for Cd suffered from moderate or severe pollution. Further spatial analysis identified the limestone mining activities, paper mills, cement factory and metallurgic activities were the main sources for the concentration of Cu, Zn, Pb and Cd in soils, and soil Ni was mainly determined by the parent materials.

Self-transducing silicon nanowire electromechanical systems at room temperature

Electronic readout of the motions of genuinely nanoscale mechanical devices at room temperature imposes an important challenge for the integration and application of nanoelectromechanical systems (NEMS). Here, we report the first experiments on piezoresistively transduced very high frequency Si nanowire (SiNW) resonators with on-chip electronic actuation at room temperature. We have demonstrated that, for very thin (~90 nm down to ~30 nm) SiNWs, their time-varying strain can be exploited for self-transducing the devices' resonant motions at frequencies as high as approximately 100 MHz. The strain of wire elongation, which is only second-order in doubly clamped structures, enables efficient displacement transducer because of the enhanced piezoresistance effect in these SiNWs. This intrinsically integrated transducer is uniquely suited for a class of very thin wires and beams where metallization and multilayer complex patterning on devices become impractical. The 30 nm thin SiNW NEMS offer exceptional mass sensitivities in the subzeptogram range. This demonstration makes it promising to advance toward NEMS sensors based on ultrathin and even molecular-scale SiNWs, and their monolithic integration with microelectronics on the same chip.

A self-sustaining ultrahigh-frequency nanoelectromechanical oscillator

Sensors based on nanoelectromechanical systems vibrating at high and ultrahigh frequencies are capable of levels of performance that surpass those of larger sensors. Nanoelectromechanical devices have achieved unprecedented sensitivity in the detection of displacement, mass, force and charge. To date, these milestones have been achieved with passive devices that require external periodic or impulsive stimuli to excite them into resonance. Here, we demonstrate an autonomous and self-sustaining nanoelectromechanical oscillator that generates continuous ultrahigh-frequency signals when powered by a steady d.c. source. The frequency-determining element in the oscillator is a 428 MHz nanoelectromechanical resonator that is embedded within a tunable electrical feedback network to generate active and stable self-oscillation. Our prototype nanoelectromechanical oscillator exhibits excellent frequency stability, linewidth narrowing and low phase noise performance. Such ultrahigh-frequency oscillators provide a comparatively simple means for implementing a wide variety of practical sensing applications. They also offer intriguing opportunities for nanomechanical frequency control, timing and synchronization.

Zeptogram-scale nanomechanical mass sensing

Very high frequency (VHF) nanoelectromechanical systems (NEMS) provide unprecedented sensitivity for inertial mass sensing. We demonstrate in situ measurements in real time with mass noise floor approximately 20 zg. Our best mass resolution corresponds to approximately 7 zg, equivalent to approximately 30 xenon atoms or the mass of an individual 4 kDa molecule. Detailed analysis of the ultimate sensitivity of such devices based on these experimental results indicates that NEMS can ultimately provide inertial mass sensing of individual intact, electrically neutral macromolecules with single-Dalton (1 amu) resolution.

Incoherent subharmonic light scattering in isotropic media

Incoherent subharmonic light scattering in isotropic media is a new kind of nonlinear light scattering, which involves single input photon and multiple output photons of equal frequency. We investigate theoretically the dependence of the subharmonic scattering intensity on the hyperpolarizability of molecules and the incident intensity using nonlinear optics theory similar to that used for Hyper-Rayleigh scattering and degenerate optical parametric oscillators. It is derived that the subharmonic scattering intensities grow exponentially or superexponentially with the hyperpolarizability of molecules and the incident intensity.

Diaquabis(ethylenediamine)copper(II) bis[tris(ethylenediamine)nickel(II)] tris(naphthalene-2,6-disulfonate) tetrahydrate

The title mixed-metal compound, [Cu(C(2)H(8)N(2))(2)(H(2)O)(2)][Ni(C(2)H(8)N(2))(3)](2)(C(10)H(6)O(6)S(2))(3).4H(2)O, was obtained during investigations of the porous frameworks constructed by amino-coordinated metal complex cations and large organic anions. All three naphthalene-2,6-disulfonate anions and the [Cu(en)(2)(H(2)O)(2)](2+) cation are located on crystallographic inversion centers and assemble into an extended two-dimensional network through intermolecular hydrogen bonds, creating cavities in which the [Ni(en)(3)](2+) cations and water molecules are included.

Bis(beta-alaninium) biphenyl-4,4'-disulfonate

In the crystal structure of the title compound, 2C(3)H(8)NO(2)(+).C(12)H(8)O(6)S(2)(2-), N-H...O hydrogen bonds formed between the amino H atoms and the sulfonate O atoms give rise to the assembly of cationic beta-alaninium dimers and centrosymmetric biphenyl-4,4'-disulfonate anions into an extended two-dimensional layer. The resulting hydrogen-bonded ribbons can be described as C(2)(2)(6)R(4)(4)(12) according to graph-set notation. C-H...O hydrogen bonds between adjacent sheets further extend the structure into a three-dimensional arrangement.

Solid-state structures of group 1 and group 2 metal 1,5-naphthalenedisulfonates: systematic investigation of lamellar three-dimensional networks constructed by metal arenedisulfonate

Seven Group 1 and Group 2 1,5-naphthalenedisulfonates (1,5-nds) have been synthesized and structurally characterized by single-crystal X-ray diffraction, IR spectroscopy and thermal gravimetric analysis. For Group 1 metal complexes, with M = Li(+) (1), Na(+) (2) and K(+) (3), all crystallize in the same space group (P2(1)/c) with the same composition, [M(2)(1,5-nds)(H(2)O)(2)]. They adopt similar three-dimensional packing arrangements with the metal-sulfonate inorganic layers pillared by naphthalene rings. However, the coordination behavior of three metal cations toward the SO(3)(-) group and water molecule are different, resulting in different architectures for the inorganic portion. For Group 2 complexes with M = Mg(2+) (4), Ca(2+) (5), Sr(2+) (6) and Ba(2+) (7), Mg(2+) shows no direct coordination by the SO(3)(-) group while Ca(2+) is coordinated by four SO(3)(-) groups and a two-dimensional network is formed. Complexes (6) and (7) are isostructural, adopting the same three-dimensional, inorganic-organic pillared framework as seen for (1)-(3). The coordination behavior of the metal cations in these structures neatly illustrates the increase in coordination strength with decreasing charge/radius ratio for Group 1 and Group 2 metal cations with large organic anions.

[Removal of PEG and salt from recombinant human tumor necrosis factor-alpha(rhTNF-alpha) with serial operation of gel filtration chromatography]

A serial gel filtration operation with the combination of G25 and G100 in one column was developed to remove salt and PEG from upper phase rich in recombinant human tumor necrosis factor alpha after simultaneous cell disruption and two-phase aqueous extraction. Buffer exchanging and primary purification were also achieved at same time. The purification factor of 4.4 was obtained with an activity recovery of 97% by one single step of serial operation.

Alterations in metastatic properties of hepatocellular carcinoma cell following H-ras oncogene transfection

AIM: To demonstrate the relationship between H-ras oncogene and hepatocellular carcinoma (HCC) metastasis.

METHODS: Activated H-ras oncogene was transfected into SMMC 7721, a cell line derived from human HCC, by calcium phosphate transfection method. Some metastasis-related parameters were detected in vitro, including adhesion assay, migration assay, expression of collagenase IV (cIVase) and epidermal growth factor receptor (EGFR).

RESULTS: The abilities of H-ras-transfected cell clones in adhesion to laminin (LN) or fibronectin (FN), migration, cIVase secretion increased markedly, and the expression of EGFR elevated moderately. More importantly, these alterations were consistent positively with the expression of p21, the protein product of H-ras oncogene.

CONCLUSION: H-ras oncogene could induce the metastatic phenotype of HCC cell in vitro to raise its metastatic potential.

Biological behavior of plasmid in Rhizobium sp. strain S25 from Tephrosia candida

Rhizobium sp. strain S25 was isolated from the nodule on Tephrosia candida in Hainan Province, China. The strain showed high stress tolerance. The plasmid profile of strain S25, examined by the Eckhardt procedure, indicated that the strain harbors only one plasmid with an estimated size of 150 kb. The plasmid was shown to carry nod and nif genes by hybridization with probes of nodABC and nifHDK genes. Plasmid curing was carried out using the Bacillus subtilis sacB to generate derivatives of strain S25. In comparison with the parent strain S25, the cured derivative lost its ability to nodulate the host plant. Loss of the plasmid reduced significantly the strain's tolerance to acid, nitrous, and multiple antibiotics. The properties of the cured strain also indicated that the plasmid was involved in carbon and nitrogen metabolism. Reintroduction of the plasmid from S25 in the cured derivative restored its original biological phenotypes.

The abundance of NM23-H1 mRNA is related with in situ microenvironment and intrahepatic metastasis in hepato-cellular carcinoma

In HCC specimens from 25 patients, the levels of nm23-H1 and H-ras mRNA were analyzed by quantitative reverse transcription-polymerase-chain reaction (RT-PCR). Tumor microvessel density (MDV), the essential factor of microenvironment and proliferating cell nucleus antigen (PCNA), indexes as tumor cell proliferating in its microenvironment are also analyzed by immunohistochemical methods using antibodies against endothelial protein factor VIII related antigen (F8RA) and antibody PC-10. Results show that The MDV and PCNA index in the group with intrahepatic metastasis is remarkably higher than that in without one (p<0.01), but the abundance of nm23-H mRNA is opposite (p<0.01). The abundance of H-ras mRNA shows little difference (p>0.05). MDV index shows directly relationship with PCNA index (p<0.01), the abundance of nm23-H1 mRNA show an inverse one with PCNA index (p<0.05). We conclude that in HCC, tumor in situ microenvironment, especially a deteriorative one, plays an important selective role. The decline of nm23-H1 mRNA abundance implies the increase of highly potential metastatic cancer cells which adapt to their microenvironment.

Postnatal developmental changes in NSE and NNE mRNA expression in the rat pineal gland: in situ hybridization histochemistry

By in situ hybridization, neuron-specific enolase (NSE) and non-neuronal enolase (NNE) mRNAs were examined in the rat pineal gland at the postnatal developmental and adult stages. The distributions of hybridized signals were analyzed in comparison with immunohistochemical staining of synaptophysin (SYN), which is a marker for pinealocytes. In SYN-positive areas that were observed throughout postnatal developmental and adult stages, we detected both NSE and NNE signals, which increased simultaneously during early postnatal development and thereafter became stationary. Quantitative analysis revealed that NNE signals were 2- to 3-fold greater in number than NSE signals at any given stage. This predominant expression pattern of NNE differed from that in neurons, which usually showed both signals at similar levels and seemed to reflect the difference in physiological function from neurons. During the early postnatal stages, a cord-like arrangement of cells without distinct SYN staining was observed. This arrangement was the thickest at postnatal day 0 and became dispersed and thinner with development, showing a relationship with formation of vascularized connective tissue stroma. By in situ hybridization, many of the constituent cells showed weak NNE signals but no distinct NSE signals. However, some cells also showed weak NSE signals, suggesting heterogeneity of these cells. The characteristic NSE and NNE expression patterns in the pineal gland cells clarified in this study might provide a basis for further studies of the differentiation and function of the pineal gland.

[The correlation between occurrence of intracranial germ cell tumors and p53 tumor suppressor gene mutations]

Using PCR-SSCP molecular biological techniques and sequencing analysis, an investigation on intracranial germ cell tumors for a correlation between the p53 tumor suppressor gene mutations and the occurrence of these tumors was performed. The results were as follows: 1. The p53 gene mutations were closely related with the development of intracranial germ cell tumors; 2. Among the germ cell tumors, different types of tumors had different p53 tumor gene mutations.

The origin of isochromosomes and their significance in tumorigenesis of human lung cancer

Isochromosomes related to chromosomes 1, 5, 6, 8, and 9 were frequently observed in 23 cases of lung cancer. Their existence in tumor cells might be nonrandom. Premature centromere separation (PCS) was found in the PGT-131 cell line of a lung cancer. It is suggested that PCS may play a role in the formation of isochromosomes in lung cancer.

Cytogenetic abnormalities in a squamous cell carcinoma of the penis

Cytogenetic findings in a squamous cell carcinoma (SCC) of the penis in a 60-year-old patient was observed for the first time. The stemline karyotype of the tumor was 46,XY,del(2) (q33q36),der(4)t(4;?)(p16;?),der(5;15)(q10;q10),der(8)t(8;?13)(p21 ;?),-13,- 13,-15,+3mar.

Direct chromosome analysis of seven primary colorectal carcinomas

Chromosome studies were performed on direct preparations of seven cases of primary colorectal carcinomas. Two cases had relatively simple chromosome changes: 48,XY,+8,+21/51, XY,+8,+9,+10,+i(17q),+21, and 47,der(X)t(X;14)(q11;q11)-Y,t(6;18)(p22;q24)+7,+8,der(19)t (19;?)(q13;?). The five others had complicated deletions and translocations; 1p- was noted in five cases, and i(17q) was noted in three cases.

Cytogenetic studies of eight primary gastric cancers

Cytogenetic analysis was performed on eight primary gastric cancers. Three of them had simple chromosome changes: 47,XX,+X/48,XX,+X,+X; 48,XX,+8,+19,t(3;5) (q21;q31) and 47,XY,+del(7)(q22). The five others had complicated chromosome changes; both 3p- and 7q- were noted in four cases and i(5p) was noted in two cases.

Cytogenetic studies of five primary esophageal cancers

In direct preparation of five primary esophageal cancers, chromosomes 1, 3, and 12 were most frequently involved in structural abnormalities; 12p- was consistently seen in all five cases and, thus, could be considered as one of the characteristic chromosome changes in esophageal cancer. Moreover, 2p-, 4p-, and 7q- were seen in three cases.

Studies on the sites expressing evolutionary changes in the structure of eukaryotic 5S ribosomal RNA

We have determined the complete sequences of 5S rRNAs from a lamprey (Lampetra reissneri), a lancelet (Branchiostoma belcheri), silkworms (Philosamia cynthia ricini, Bombyx mori, Antheraea pernyi), and a silkworm hybrid (artificially fertilized hybrid species of Philosamia cynthia ricini male x Bombyx mori female), as well as those of cotton seeds (Gossypium hirsutum L.). Having compared more than 170 eukaryotic 5S rRNAs of which seven sequences have been determined by our group as mentioned above, we have found that the "evolutionary sites" that exist at special locations in these structures are closely related to the evolution of eukaryotes. The changes proceed step by step in an orderly way, i.e., the change in nucleotide residues of the "evolutionary sites" depends on the order of the evolution of the species and shows group-specific patterns.