MicroRNAs: A novel signature in the metastasis of esophageal squamous cell carcinoma

Esophageal squamous cell carcinoma (ESCC) is a malignant epithelial tumor, characterized by squamous cell differentiation, it is the sixth leading cause of cancer-related deaths globally. The increased mortality rate of ESCC patients is predominantly due to the advanced stage of the disease when discovered, coupled with higher risk of metastasis, which is an exceedingly malignant characteristic of cancer, frequently leading to a high mortality rate. Unfortunately, there is currently no specific and effective marker to predict and treat metastasis in ESCC. MicroRNAs (miRNAs) are a class of small non-coding RNA molecules, approximately 22 nucleotides in length. miRNAs are vital in modulating gene expression and serve pivotal regulatory roles in the occurrence, progression, and prognosis of cancer. Here, we have examined the literature to highlight the intimate correlations between miRNAs and ESCC metastasis, and show that ESCC metastasis is predominantly regulated or regulated by genetic and epigenetic factors. This review proposes a potential role for miRNAs as diagnostic and therapeutic biomarkers for metastasis in ESCC metastasis, with the ultimate aim of reducing the mortality rate among patients with ESCC.

Sequential 2.5 mg letrozole/FSH therapy is more effective for promoting pregnancy in infertile women with PCOS: a pragmatic randomized controlled trial

Study question

In infertile women with polycystic ovary syndrome (PCOS), is the sequential use of letrozole 2.5 mg/follicle stimulating hormone(FSH) more effective than letrozole 5 mg/FSH in stimulating ovulation and promoting pregnancy?

Research design and methods

The study was designed as a prospective, single-center, randomized, controlled pragmatic clinical trial. 220 infertile women between the ages of 20 and 40, who matched the Rotterdam criteria for PCOS and had no other identified reasons for infertility were enrolled from April 2023 to July 2023.The participants were randomly assigned to two groups in a 1:1 ratio. One group received 2.5 mg of letrozole on cycle days 3-7 with a sequential injection of 75 IU FSH on cycle days 8-10 (n = 110), while the other group received 5 mg of letrozole on cycle days 3-7 with a sequential injection of 75 IU FSH on cycle days 8-10 (n = 110). The duration of FSH treatment varied depending on the follicular development stage. Each participant underwent one to three treatment cycles until achieving pregnancy.The primary outcome was the cumulative pregnancy rate of all the participants. Secondary outcomes included characteristics and clinical pregnancy rates of all the intervention cycles.

Results

For all 220 participants, the sequential letrozole 2.5 mg/FSH treatment group had a significantly higher cumulative pregnancy rate compared to the letrozole 5 mg/FSH treatment group (72.7% versus 59.1%, RR (95%CI) = 1.23 (1.02, 1.49), P-value = 0.033). For all 468 intervention cycles, letrozole 2.5 mg/FSH group had a significantly higher clinical pregnancy rate than the letrozole 5 mg/FSH group (36.2% versus 26.3%, P-value = 0.021), no statistically significant differences were observed in ovulation rates or adverse effects.

Conclusions

The data indicate that the sequential letrozole 2.5mg/FSH protocol may be more effective than the sequential letrozole 5mg/FSH protocol for promoting pregnancy in infertile women with PCOS.

Clinical trial registration

www.chictr.org.cn, identifier ChiCTR2300069638.

[Epidemiological characteristics of reinfection of 2019-nCoV and influencing factors in Ningbo]

Objective: To analyze the epidemiological characteristics of reinfection of 2019-nCoV and influencing factors, and provide evidence for effective prevention and control of COVID-19 epidemic. Methods: The incidence data of COVID-19 in Ningbo from January 1, 2020 to November 30, 2022 were collected from the infectious disease surveillance system of Chinese information system for disease control and prevention. The incidence of reinfection of 2019-nCoV was investigated by using questionnaire. logistic regression analysis was used to analyze the influences of gender, age, time interval from the first infection, history of underlying disease, 2019-nCoV vaccination dose and disease severity on the reinfection. Results: A total of 897 previous 2019-nCoV infection cases were investigated, of which 115 experienced the reinfection of 2019-nCoV, the reinfection rate was 12.82%. The interval between the two infections M(Q1, Q3) was 1 052 (504, 1 056) days. Univariate analysis showed that age, 2019-nCoV vaccination dose, history of underlying disease, type of 2019-nCoV variant causing the first infection, time interval from the first infection and severity of the first infection were associated with the reinfection rate (all P<0.05). Multivariate logistic regression analysis showed that the risk for reinfection in age group 30- years was higher than that in age group ≥60 years (OR=2.10, 95%CI: 1.11-3.97). No reinfection occurred in those with time interval from the first infection of <6 months, and the risk for reinfection was higher in those with the time interval of ≥12 months than in those with the time interval of 6- months (OR=6.68, 95%CI: 3.46-12.90). The risk for reinfection was higher in the common or mild cases than in the asymptomatic cases (OR=2.64, 95%CI: 1.18-5.88; OR=2.79, 95%CI: 1.27-6.11). Conclusion: The time interval from the first infection was an important influencing factor for the reinfection of 2019-nCoV, and the probability of the reinfection within 6 months was low.

MALAT1 binds to miR-188-3p to regulate ALOX5 activity in the lung inflammatory response of neonatal bronchopulmonary dysplasia

Bronchopulmonary dysplasia (BPD) causes high morbidity and mortality in infants, but no effective preventive or therapeutic agents have been developed to combat BPD. In this study, we assessed the expression of MALAT1 and ALOX5 in peripheral blood mononuclear cells from BPD neonates, hyperoxia-induced rat models and lung epithelial cell lines. Interestingly, we found upregulated expression of MALAT1 and ALOX5 in the experimental groups, along with upregulated expression of proinflammatory cytokines. According to bioinformatics prediction, MALAT1 and ALOX5 simultaneously bind to miR-188-3p, which was downregulated in the experimental groups above. Silencing MALAT1 or ALOX5 and overexpressing miR-188-3p inhibited apoptosis and promoted the proliferation of hyperoxia-treated A549 cells. Suppressing MALAT1 or overexpressing miR-188-3p increased the expression levels of miR-188-3p but decreased the expression levels of ALOX5. Moreover, RNA immunoprecipitation (RIP) and luciferase assays showed that MALAT1 directly targeted miR-188-3p to regulate ALOX5 expression in BPD neonates. Collectively, our study demonstrates that MALAT1 regulates ALOX5 expression by binding to miR-188-3p, providing novel insights into potential therapeutics for BPD treatment.

Brucellosis complicated by myelofibrosis: report of five cases and review of literature

Myelofibrosis is a myeloproliferative tumor, that can be secondary to malignant hematologic or inflammatory diseases, such as chronic myeloid leukemia, polycythemia vera, primary thrombocythemia, multiple myeloma, disseminated tuberculosis, or vasculitis. However, few cases of brucellosis-associated myelofibrosis have been reported. Moreover, due to the rarity of this phenomenon, it is often overlooked by clinicians, resulting in misdiagnosis and mismanagement. Thus, brucellosis should be considered as a possible cause of myelofibrosis. In the present study, we report five cases of brucellosis, of which three had myelofibrosis. In addition, to further determine the potential link between brucellosis and myelofibrosis, we retrospectively analyzed the levels of various cytokines by collecting the clinicopathologic data of patients and using immunohistochemical staining. We found that brucellosis patients with myelofibrosis had elevated levels of cytokines such as interferon (IFN)-γ, interleukin (IL)-1β, basic fibroblast growth factor (b-FGF), vascular endothelial growth factor (VEGF), suggesting that the regulation of cytokines may play a central role in the development of myelofibrosis in patients with brucellosis.

[Pharmacokinetics and tissue distribution of four alkaloids in Ermiao Pills and Sanmiao Pills in normal and arthritic model rats]

This work aimed to investigate the differences of pharmacokinetics and tissue distribution of four alkaloids in Ermiao Pills and Sanmiao Pills in normal and arthritic model rats. The rat model of arthritis was established by injecting Freund's complete adjuvant, and ultra-high performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS) in the positive ion multiple reaction monitoring(MRM) mode was used for the determination of four alkaloids in plasma and tissues of normal and arthritic rats after administration of Ermiao Pills and Sanmiao Pills, respectively. The differences in pharmacokinetics and tissue distribution of the four active components were compared, and the effect of Achyranthis Bidentatae Radix on the major components of Sanmiao Pills was explored. This study established an UPLC-MS/MS for simultaneous determination of four alkaloids, and the specificity, linearity, accuracy, precision, and stability of this method all met the requirements. Pharmacokinetics study found that as compared with normal rats, the AUC and C_(max) of phellodendrine, magnoflorine, berberine and palmatine in model rats were significantly decreased after administration of Ermiao Pills, the clearance rate CL/F was significantly increased, and the distribution and tissue/plasma concentration ratio of the four alkaloids in the liver, kidney, and joint were significantly reduced. Achyranthis Bidentatae Radix increased the AUC of phellodendrine, berberine, and palmatine, reduced the clearance rate, and significantly increased the distribution of the four alkaloids in the liver, kidney, and joints in arthritic rats. However, it had no significant effect on the pharmacokinetics and tissue distribution of the four alkaloids in normal rats. These results suggest that Achyranthis Bidentatae Radix may play a guiding role in meridian through increasing the tissue distribution of effective components in Sanmiao Pills under arthritis states.

[Isoquinoline alkaloids from two species of Thalictrum genus plants]

The chemical constituents from the roots of Thalictrum cultratum and T. baicalense were investigated. By various isolation methods, such as silica gel, aluminium oxide, ODS, and Sephadex LH-20 column chromatographies, and semi-preparative HPLC, 11 simple isoquinoline alkaloids were isolated from the ethanol extract of the roots of these two plants, including a new compound, named dehydrothalflavine(1), and ten known ones(2-11): N-methylcorydaline(2), N-methylthalidaldine(3), thaliflavine(4), oxyhydrastinine(5), noroxyhydrastinine(6), dimethoxyisoquinolone(7), thalactamine(8), dehydronoroxyhydrastinine(9), 6,7-dimethoxy-2-methyl-1,2,3,4-tetrahydroisoquinoline(10), and isopicnarrhine(11). Their structures were elucidated on the basis of HR-ESI-MS and 1 D and 2 D NMR techniques. Compound 1 was a new isoquinoline alkaloid. Compound 11 was obtained from Tha-lictrum plant for the first time. All compounds did not show cytotoxic activities against HL-60, U937, HCT116, Caco-2, and HepG2 cancer cell lines.

Skimmianine as a novel therapeutic agent suppresses proliferation and migration of human esophageal squamous cell carcinoma via blocking the activation of ERK1/2

Esophageal squamous cell carcinoma (ESCC), one of the main histopathological subtypes of esophageal cancer (EC), is characterized by high morbidity and mortality. Clinical treatment for ESCC lacks specific molecular targets and effective therapeutic drugs. Skimmianine (SK), one of the natural fluroquinolone alkaloids, is widely present in Rutaceae family plants. Here, we mainly used CCK-8 assay, clone formation, flow cytometry analysis, wound-healing assay, Transwell assay, western blot, quantitative real-time PCR (qRT-PCR), molecular docking analysis, tumor xenograft assay, and immunohistochemistry (IHC) staining to investigate the potential anti-tumor effect of SK on ESCC. We demonstrated that SK inhibited the proliferation of TE-1 and Eca109 cells via inducing the G0/G1 phase cell cycle arrest, prevented the migration and invasion of tumor cells via regulating epithelial-mesenchymal transition (EMT) in vitro. In addition, SK obviously suppressed the growth of xenografted Eca109 tumors in nude mice. The anti-tumor mechanism of SK could be blocking the activation of extracellular signal-regulated kinases 1/2 (ERK1/2) in the mitogen-activated protein kinase (MAPK)/ERK signaling pathway. Our basic research suggests that SK can be a potential therapeutic agent for ESCC.

[Pollution Characteristics and Health Risk Assessment of Perfluorinated Compounds in PM2.5 in Zhejiang Province]

As typical new pollutants, perfluorinated compounds (PFCs) have been widely concerned by environmental workers in recent years. This study was carried out to investigate the pollution characteristics of perfluorinated compounds in atmospheric particulate matter (PM_2.5) in Zhejiang Province. The chemical extraction of PM_2.5 was performed using the accelerated solvent extraction (ASE) method with mixed dichloromethane and acetone (2:1). The chemical analysis was implemented by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The results showed that the daily average concentration of the sum of 12 PFCs (Σ₁₂ PFCs) ranged from 131.63 pg·m^-3 to 578.53 pg·m^-3, which was slightly higher in winter compared to that in autumn. The concentrations of perfluorosulfonic acids (PFSAs) were much lower than those of perfluorocarboxylic acids (PFCAs). PFOS was the primary contaminant among PFASs, with an average concentration of 12.90 pg·m^-3. The content of PFCAs exhibited a trend of PFOA>PFHxA>PFHpA, and the detection rate of long-chain PFCs was much lower than that of short-chain PFCs. The hysplit-4 model was used to calculate the QZ air mass transport trajectory. The results indicated that the backward trajectory of this point was significantly different along time, and the source of air mass rarely affected the concentration. The forward trajectory confirmed that PFCs can be transmitted over long distances in the atmosphere in a short time. The correlation coefficient between PFUdA and PFTeDA was evaluated to be 0.68, and that between PFHxS and PFOS was 0.66, suggesting the same sources of these chemicals. The content of PFCs was positively correlated with PM_2.5, indicating that people might suffer from higher health risks on haze days. The risk quotient estimation implied no health risk of PFCs in PM_2.5 in Zhejiang Province.

Rutaecarpine enhances the anti-diabetic activity and hepatic distribution of metformin via up-regulation of Oct1 in diabetic rats

Diabetes mellitus is a chronic metabolic disorder with multiple complications, patients who receive metformin may have a simultaneous intake of herbal medicine containing rutaecarpine due to cardiovascular protection and hypolipidemic effects of rutaecarpine. There might be drug interactions between metformin and rutaecarpine. This study aimed to investigate the effects of rutaecarpine on the pharmacodynamics and pharmacokinetics of metformin in diabetic rats.The diabetic rat model was induced with high-fat diet and low dose streptozotocin. Metformin with or without rutaecarpine was administered by oral gavage for 42 days. Pharmacodynamics and pharmacokinetics parameters were evaluated.The pharmacodynamics results revealed that co-administration of rutaecarpine with metformin resulted in a remarkable reduction of serum glucose and lipid profiles in diabetic rats compared to metformin treated alone. The pharmacokinetics results showed that co-treatments of rutaecarpine with metformin did not affect the systemic exposure and renal distribution of metformin, but increased metformin concentration in liver. Furthermore, rutaecarpine increased Oct1-mediated metformin uptake into hepatocytes by upregulation of Oct1 expression in the liver.The above data indicate that rutaecarpine enhanced the anti-diabetic effect of metformin, which may be associated with the increased hepatic distribution of metformin through up-regulation of Oct1 in response to rutaecarpine.

[Analysis of clinical features of cervical precancerous lesions in postmenopausal women]

Objective: To analyze the characteristics of high-grade squamous intraepithelial lesion (HSIL) diagnosed by cervical tissue sampling in postmenopausal women. Methods: A retrospective study was performed on 2 013 patients with HSIL diagnosed by cervical tissue sampling under colposcopy and treated by cervical conization at the First Affiliated Hospital of Zhengzhou University from June 2017 to November 2018, to compare the difference of patients' clinical features, HPV test, liquid-based thin-layer cytology (TCT), performance of colposcopy and biopsy pathology, pathology after cervical conization between 439 postmenopausal patients and 1 574 pre-menopausal patients. Results: (1) Clinical features: the proportion of contact bleeding showed no significant difference between postmenopausal patients and pre-menopausal patients [4.3% (19/439) vs 6.4% (101/1 574); χ²=2.672, P=0.102]. Among the patients with contact bleeding, the proportion of cervical cancer after cervical cone resection was significantly higher in postmenopausal patients compared with pre-menopausal patients [10/19 vs 22.8% (23/101); χ²=7.157, P=0.007]. Among the patients found by routine screening, the proportion of cervical cancer after cervical cone resection was significantly higher in postmenopausal patients compared with pre-menopausal patients [9.0% (38/420) vs 4.3% (63/1 473); χ²=14.726, P<0.01]. The proportion of smooth cervix was higher in postmenopausal patients compared with pre-menopausal patients [63.6% (279/439) vs 35.5% (558/1 574); χ²=111.601, P<0.01]. (2) High-risk HPV infection: there was no significant difference in the high-risk HPV positive rate between the postmenopausal group and the pre-menopausal group [92.0% (404/439) vs 94.4% (1 486/1 574); χ²=3.394, P=0.065]; the HPV 16 infection was the most common type, but there was no significant difference in the HPV 16 infection rate between the two groups [65.8% (289/439) vs 68.0% (1 070/1 574); χ²=0.722, P=0.395]. (3) TCT test: TCT test results included negative for intraepithelial lesion and malignancy (NILM), atypical squamous cell of undetermined signification (ASCUS), atypical squamous cells cannot exclude high-grade lesion (ASC-H), low grade squamous intraepithelial lesion (LSIL), HSIL, compared with the different results of TCT examination, there were not statistically significant difference between postmenopausal and pre-menopausal patients (all P>0.05). (4) The performance of colposcopy: the proportion of insufficient colposcopy and the proportion of cervical type Ⅲ conversion area were higher in postmenopausal patients compared with pre-menopausal patients [87.5% (384/439) vs 32.5% (511/1 574), P<0.01; 80.0% (351/439) vs 21.9% (344/1 574), P<0.01]. The proportion and positive rate of endocervical curettage (ECC) in postmenopausal patients were higher than those in pre-menopausal patients [35.3% (155/439) vs 20.4% (322/1 574), P<0.01; 67.7% (105/155) vs 53.1% (171/322), P=0.003]. The proportion of lesions involving the vaginal wall was higher in postmenopausal patients compared with pre-menopausal patients [5.9% (26/439) vs 1.0% (16/1 574); χ²=40.443, P<0.01]. There was a positive correlation between vaginal wall lesions and cervical lesions in postmenopausal patients (r=0.660, P<0.01). (5) Postoperative pathology: the positive rate of margin and the proportion of pathological escalation after cervical conization were significantly higher in postmenopausal patients compared with pre-menopausal patients [14.6% (64/439) vs 4.8% (75/1 574), 10.9% (48/439) vs 5.5% (86/1 574); P<0.01]. Conclusions: Colposcopy in postmenopausal women is often inadequate, and the cervix is mostly type Ⅲ transformation zone. The lesion in postmenopausal women is more likely to involve the cervical canal and vaginal wall. Clinical attention should be paid to cervical tube curettage and comprehensive examination of the vaginal wall. The high rate of positive margins and a high proportion of pathological upgrading after cervical conization in postmenopausal patients requires further active intervention.

Promotion of Bronchopulmonary Dysplasia Progression Using Circular RNA circabcc4 via Facilitating PLA2G6 Expression by Sequestering miR-663a

Circular RNA (circRNA) has been increasingly proven as a new type of promising therapeutic RNA molecule in a variety of human diseases. However, the role of circRNA in bronchopulmonary dysplasia (BPD) has not yet been elucidated. Here, a new circRNA circABCC4 was identified from the Agilent circRNA chip as a differentially expressed circRNA in BPD. The relationship between circABCC4 level and BPD clinicopathological characteristics was analyzed. The function of circABCC4 was evaluated by performing CCK-8 and apoptosis analysis in vitro and BPD model analysis in vivo. RNA immunoprecipitation (RIP), luciferase reporter and rescue experiments were used to elucidate the interaction between circABCC4 and miR-663a. Luciferase reporter assay and rescue experiments were used to elucidate the interaction between PLA2G6 and miR-663a. CircABCC4 and PLA2G6 levels were increased, while miR-663a levels were decreased in the BPD group, compared to the control group. MiR-663a inhibited apoptosis by repressing PLA2G6 expression, while circABCC4 enhanced the apoptosis and inhibited the proliferation of A549 cells by sponging miR-663a and increasing PLA2G6 expression. In conclusion, circABCC4 promotes the evolving of BPD by spongening miR-663a and up-regulating PLA2G6 expression, which makes circABCC4 an ideal molecular target for early diagnosis and intervention of BPD.

Effect and Safety of Tongyan Spray () on Hyoid Motion in Patients with Dysphagia after Ischemic Stroke

OBJECTIVE

To observe the effects and safety of Tongyan Spray () on the range and time of hyoid motion in patients with ischemic post-stroke dysphagia.

METHODS

Seventy-two patients with ischemic post-stroke dysphagia were selected and randomly assigned to a treatment group (36 cases) and a control group (36 cases) by a random number table from January 2013 to October 2014. All patients swallowed 4 kinds of barium meals with different traits respectively, and each patient underwent video fluoroscopy (VF) examination twice. In the treatment group, Tongyan Spray was sprayed to the pharynx on both sides and the middle part once respectively. The spray was applied 30 min before the second examination. Purified water at room temperature was used as placebo in the control group. The changes in the range and time of hyoid motion in both groups were observed before and after treatment.

RESULTS

Six patients dropped out in each group, and 60 patients completed the study and were included in the final analysis. Significant improvement was observed in the range of superior hyoid excursion distance and the time of hyoid motion in the treatment group compared with the control group (P<0.05). There were no obvious adverse reactions observed in oral mucosa in both groups during the whole study.

CONCLUSION

Tongyan Spray was an effective and safe medicine for improving swallowing function in patients with ischemic post-stroke dysphagia.

[Grading evaluation of operative complications and analysis of related risk factors in patients with stage Ⅰ endometrial cancer treated by robotic-assisted and traditional laparoscopic surgery]

Objective: To investigate the surgical complications in the treatment of stage Ⅰ endometrial cancer by robotic-assisted laparoscopy, the risk degree of Clavein-Dindo complications and the main risk factors affecting the occurrence of surgical complications. Methods: A retrospective case-control study was conducted in the First Affiliated Hospital of Zhengzhou University from October 2014 to June 2019. The patients were divided into robotic-assisted laparoscopy group and traditional laparoscopy group according to the operation mode, including 131 cases in robot group and 290 cases in traditional laparoscopy group. To compare the complications during and after operation and the risk degree of complications between the two groups by Clavein-Dindo classification standard, the age, body mass index (BMI), comorbidities, past history of pelvic surgery, American Society of Anesthesiologists (ASA) grade, preoperative anemia, number of pelvic lymph node resection, number of abdominal aortic lymph node resection, the total number of lymph node resection, operation time, surgical methods (robot surgery or traditional laparoscopic surgery) and other clinicopathological data were analyzed by logistic regression analysis. Results: (1) Complications of operation: the incidence of operative complications (including intraoperative and postoperative complications) in robot group was significantly lower than that in traditional laparoscopy group [(20.6%, 27/131) vs (34.8%, 101/290); χ(2)=8.620, P=0.003)]. The incidence of intraoperative complications in robot group was lower than that in traditional laparoscopy group [1.5% (2/131) vs 6.2% (18/290); χ(2)=4.368, P=0.037]. The incidence of intraoperative vascular injury in robot group was significantly lower than that in traditional laparoscopy group [0.8% (1/131) vs 5.2% (15/290); χ(2)=4.798, P=0.022]. The incidence of postoperative complications in robot group was also lower than that in traditional laparoscopy group [19.1% (25/131) vs 28.6% (83/290); χ(2)=4.303, P=0.038], but the incidence of postoperative lymphatic leakage in robot group was higher than that in traditional laparoscopy group [10.7% (14/131) vs 5.2% (15/290); χ(2)=4.279, P=0.039]. (2) Clavein-Dindo classification: the incidence of Clavein-Dindo Ⅰ, Ⅲ, Ⅲ, Ⅳ and Ⅴ grade between two groups were respectively 3.8% (5/131) vs 11.0% (32/290), 13.7% (18/131) vs 14.5% (42/290), 3.1% (4/131) vs 8.6% (25/290), 0 (0/131) vs 0.3% (1/290), 0 (0/131) vs 0.3% (1/290), and the incidence of grade Ⅰ (χ(2)=5.684, P=0.015) and Ⅲ (χ(2)=4.361, P=0.037) complications were statistically significant. The incidence of severe complications in robot group (grade Ⅲ and above) was lower than that in traditional laparoscopy group [3.1% (4/131) vs 9.3% (27/290); χ(2)=5.179, P=0.023]. (3) Analysis of influencing factors of surgical complications: univariate analysis showed that BMI (χ(2)=15.801, P=0.000), preoperative anemia (χ(2)=14.299, P=0.000), total number of lymph node resection (χ(2)=10.425, P=0.001), surgical methods (χ(2)=8.620, P=0.003) were related to the occurrence of surgical complications of endometrial carcinoma. Multivariate analysis showed that BMI (OR=0.289, 95%CI: 0.097-0.864, P=0.026), preoperative anemia (OR=0.309, 95%CI: 0.129-0.740, P=0.008), the total number of lymph node resection (OR=0.624, 95%CI: 0.403-0.966, P=0.034) and surgical methods (OR=3.491, 95%CI: 1.030-11.840, P=0.045) were independent risk factors for surgical complications of endometrial carcinoma. Conclusions: Compared with traditional laparoscopic surgery, robot-assisted laparoscopic surgery has fewer complications and lower incidence of severe complications. BMI, preoperative anemia, the total number of lymph node resection and surgical methods are independent risk factors for the occurrence of surgical complications of stage Ⅰ endometrial cancer.

Lipoxin A4 attenuates hyperoxia‑induced lung epithelial cell injury via the upregulation of heme oxygenase‑1 and inhibition of proinflammatory cytokines

The present study examined whether lipoxin A4 (LXA4) increases the expression of HO‑1, and inhibits the production of interleukin 6 (IL‑6) and monocyte chemotactic protein 1 (MCP‑1) in LXA4‑induced protection during hyperoxia‑induced injury in murine lung epithelial cells (MLE‑12) and what signal pathway may participate in the actions of LXA4 inhibiting IL‑6 and MCP‑1. MLE‑12 cells were exposed to air or hyperoxia with or without pretreatment with LXA4, Zinc protoporphyrin IX (ZnPP‑IX), IL‑6, anti‑IL‑6, MCP‑1, anti‑MCP‑1, inhibitors of p38 mitogen‑activated protein kinase (p38 MAPK), protein kinase B (Akt) and extracellular signal‑regulated kinase 1/2 (ERK1/2) signaling pathways. The cell survival rates, cell viability, apoptosis rates, expression of superoxide dismutase (SOD), heme oxygenase‑1 (HO‑1), IL‑6 and MCP‑1, and the activations of p38 MAPK, ERK1/2 and Akt were measured. LXA4 significantly increased the cell survival rates, cell viability, SOD levels and HO‑1 expression, reduced the apoptosis rates, and inhibited the MCP‑1 and IL‑6 levels induced by hyperoxia in cells. ZnPP‑IX, an inhibitor of HO‑1, blocked LXA4‑induced protection on cell viability in cells exposed to hyperoxia. Anti‑IL‑6 and anti‑MCP‑1 improved the cell viability of cells exposed to hyperoxia. Inhibition of p38 MAPK and ERK1/2 blocked the expression of MCP‑1 and IL‑6 induced by hyperoxia. LXA4 inhibited the activation of p38 MAPK and ERK1/2 induced by hyperoxia, and increased the activation of the Akt signaling pathway, which was inhibited by hyperoxia. Therefore, LXA4 attenuated hyperoxia‑induced injury in MLE‑12 cells via the upregulation of HO‑1 expression. The protection of LXA4 in hyperoxia‑induced cell injury may be associated with the downregulation IL‑6 and MCP‑1 levels via the inhibition of the p38 MAPK and ERK1/2 signaling pathways.

Atomically Precise Gold-Levonorgestrel Nanocluster as a Radiosensitizer for Enhanced Cancer Therapy

Gold nanoclusters have become promising radiosensitizers due to their ultrasmall size and robust ability to adsorb, scatter, and re-emit radiation. However, most of the previously reported gold nanocluster radiosensitizers do not have a precise atomic structure, causing difficulties in understanding the structure-activity relationship. In this study, a structurally defined gold-levonorgestrel nanocluster consisting of Au₈(C₂₁H₂₇O₂)₈ (Au₈NC) with bright luminescence (58.7% quantum yield) and satisfactory biocompatibility was demonstrated as a nanoradiosensitizer. When the Au₈NCs were irradiated with X-rays, they produced reactive oxygen species (ROS), resulting in irreversible cell apoptosis. As indicated by in vivo tumor formation experiments, tumorigenicity was significantly suppressed after one radiotherapy treatment with the Au₈NCs. In addition, compared with tumors treated with X-rays (4 Gy) alone, tumors treated with the nanosensitizer exhibited an inhibition rate of 74.2%. This study contributes to the development of atomically precise gold nanoclusters as efficient radiosensitizers.

Combination of Preoperative D-Dimer and Platelet Distribution width Predicts Postoperative Deep Venous Thrombosis in Patients with Cervical Carcinoma

Background:

Deep venous thrombosis (DVT) is associated with severe morbidity and mortality in cancer. Platelet distribution width (PDW), a platelet index, indicates variation in platelet size. We aimed to investigate whether the combination of D-dimer and PDW could have a better performance in predicting DVT in patients with cervical carcinoma.

Materials and Methods:

In 198 consecutive cervical carcinoma patients without preoperative DVT, preoperative D-dimer and PDW levels were measured. Compression ultrasonography was performed in all cervical carcinoma patients before surgery, as well as one month, three months, six months, and 12 months.

Results:

During a median period of 12 months, 17 of the 198 patients (8.6 %) developed DVT. PDW levels were reduced and D-dimer levels were increased in patients with DVT events compared to those without DVT. Multivariate Cox analysis revealed that both PDW and D-dimer were independent predictors for DVT events. The area under the ROC curve was 0.628 (95% CI: 0.556 to 0.695, p=0.142) when D-dimer was used alone, whereas it increased to 0.777 (95% CI: 0.712 to 0.833, p<0.011) with the addition of PDW. Incorporation of PDW into the D-dimer model significantly improved the predictive value.

Conclusions:

The combination of preoperative D-dimer and PDW improves the predictive power of postoperative DVT risk in patients with cervical carcinoma.

miR-375 inhibits the proliferation and invasion of glioblastoma by regulating Wnt5a

The aberrant expression of microRNA-375 (miR-375) has been proved to be associated with carcinogenesis. However, the role of miR-375 in glioblastoma (GBM) remains unknown. The aim of this study was to investigate biological functions and its molecular mechanisms of miR-375 in GBM cells. In this study, real-time PCR results showed that the level of miR-375 expression in GBM tissues and GBM cell lines (U87 and U251) was decreased. Using MTT assay, Transwell migration and invasion assay, we demonstrated that miR-375 overexpression significantly suppress cell proliferation, cell migration and cell invasion capacity in U87 and U251 cells. However, downregulation of miR-375 had reverse effects on cell proliferation, migration and invasion. Targeting association analysis, dual luciferase assay, RT-PCR and western blot analysis results confirmed that miR-375 could target the 3'UTR of Wnt5a mRNA and regulated its protein expression. Further studies also find overexpression of Wnt5a could significantly reverse miR-375-mediated proliferation, migration and invasion on U87 and U251 cells. Therefore, we concluded that miR-375 inhibited the proliferation and invasion of GBM by regulating Wnt5a and might be a possible therapeutic agent for GBM.

Identification of an (AC)n microsatellite in the Six1 gene promoter and its effect on production traits in Pietrain × Duroc × Landrace × Yorkshire pigs

The Sine oculis homeobox 1 (Six1) gene is important for skeletal muscle growth and fiber specification; therefore, it is considered as a promising candidate gene that may influence porcine growth and meat quality traits. Nevertheless, the association of Six1 with these processes and the mechanisms regulating its expression remain unclear. The objectives of this study were to identify variant sites of Six1 in different pig breeds, conduct association analysis to evaluate the relationship between polymorphisms of these variants and porcine production traits in Pietrain × Duroc × Landrace × Yorkshire commercial pigs, and explore the potential regulatory mechanisms of Six1 affecting production traits. A total of 12 variants were identified, including 10 single- nucleotide variations (SNVs), 1 insertion- deletion (Indel), and 1 (AC)n microsatellite. Association analysis demonstrated that the SNV, g.1595A>G, was significantly associated with meat color (redness, a*); individuals with the G allele had greater a* values (P < 0.05). Moreover, our results demonstrated that the (AC)n polymorphism in the Six1 promoter was significantly associated with weaning weight (P < 0.05), carcass weight (P < 0.05), and thoracic and lumbar back fat (P < 0.01).In addition, we found that the (AC)n variant was closely related with Six1 expression levels and demonstrated this polymorphism on promoter activity by in vitro experiments. Overall, this study provides novel evidence for elucidating the effects of Six1 on porcine production traits as promising candidate and describes two variants with these traits, which are potential reference markers for pig molecular breeding. In addition, our data on the relationship between porcine Six1 expression and the polymorphic (AC)n microsatellite in its promoter may facilitate similar studies in other species.

Motor imagery training induces changes in brain neural networks in stroke patients

Motor imagery is the mental representation of an action without overt movement or muscle activation. However, the effects of motor imagery on stroke-induced hand dysfunction and brain neural networks are still unknown. We conducted a randomized controlled trial in the China Rehabilitation Research Center. Twenty stroke patients, including 13 males and 7 females, 32–51 years old, were recruited and randomly assigned to the traditional rehabilitation treatment group (PP group, n = 10) or the motor imagery training combined with traditional rehabilitation treatment group (MP group, n = 10). All patients received rehabilitation training once a day, 45 minutes per session, five times per week, for 4 consecutive weeks. In the MP group, motor imagery training was performed for 45 minutes after traditional rehabilitation training, daily. Action Research Arm Test and the Fugl-Meyer Assessment of the upper extremity were used to evaluate hand functions before and after treatment. Transcranial magnetic stimulation was used to analyze motor evoked potentials in the affected extremity. Diffusion tensor imaging was used to assess changes in brain neural networks. Compared with the PP group, the MP group showed better recovery of hand function, higher amplitude of the motor evoked potential in the abductor pollicis brevis, greater fractional anisotropy of the right dorsal pathway, and an increase in the fractional anisotropy of the bilateral dorsal pathway. Our findings indicate that 4 weeks of motor imagery training combined with traditional rehabilitation treatment improves hand function in stroke patients by enhancing the dorsal pathway. This trial has been registered with the Chinese Clinical Trial Registry (registration number: ChiCTR-OCH-12002238).

[Telbivudine for prevention of perinatal transmission in pregnant women infected with hepatitis B virus in immune-tolerant phase: a study of efficacy and safety of drug withdrawal]

OBJECTIVE

To observe the success rate of telbivudine (LdT) for the prevention of perinatal transmission of hepatitis B virus (HBV) and the incidence of alanine aminotransferase (ALT) elevation during LdT treatment and after LdT withdrawal in HBV-infected pregnant woman with high viremia in immune-tolerant phase and receiving LdT treatment at the end of pregnancy, and to evaluate the efficacy of LdT in the prevention of perinatal transmission and the safety for pregnant women.

METHODS

Pregnant women infected with HBV in immune-tolerant phase who had normal ALT levels (≤40 U/L) and high viremia (HBV DNA ≥6 log10 IU/ml) with positive HBeAg were enrolled as subjects. All pregnant women received antiviral treatment with LdT at the end of pregnancy to prevent perinatal transmission of HBV. All infants received standard combined immunoprophylaxis. Failure for prevention of perinatal transmission of HBV was defined as positive HBsAg or HBV DNA in infants 7 months of age (or at one month after the third injection of hepatitis B vaccine). Liver function, HBV DNA, and HBV serological markers were evaluated at baseline, after 1 month of treatment, before childbirth, and 1, 3, and 6 months after drug withdrawal. SPSS 16.0 software was used to analyze the data. Between-group comparison of continuous data was made by t test, and comparison of categorical data was made by chi-square test.

RESULTS

One hundred and four pregnant women (treatment group) received oral administration of 600 mg LdT once a day, and 25 pregnant women (observation group) did not receive any antiviral therapy. The success rate for the prevention of perinatal transmission was significantly higher in the treatment group than in the observation group (100% vs 89.47%, χ (2) = 9.862, P = 0.028). There was no significant difference in the incidence of ALT elevation during treatment and within 6 months after drug withdrawal between the treatment group and the observation group (4.81% (5/104) vs 4.00% (1/25), χ (2) = 0.030, P = 1.000). In the treatment group, the mean HBV DNA at baseline was significantly higher than that before childbirth (8.20±0.78 vs 3.98±0.90 log10IU/ml, t = 6.979, P < 0.001). One hundred patients with drug withdrawal had HBV DNA increased to 8.11±0.80 log10 IU/ml at one month after childbirth.

CONCLUSION

LdT treatment at the end of pregnancy can effectively reduce the incidence of perinatal transmission of HBV in pregnant women with high viremia in immune-tolerant phase. The immediate drug withdrawal after childbirth is safe for the mother. The incidence of hepatitis is low after drug withdrawal.

Enhancing local luminescence in a hollow ZnO microcolumn by antiresonant reflecting

Hollow ZnO microcolumns with size induced photoluminescence and cathodoluminescence properties were prepared by a thermal chemical vapor transport and condensation method. It was found that the luminescence emission could be confined in the nano-sized hollow core and the wavelength dependent light intensity could be influenced by the geometric structure of the ZnO microcolumn, which can act as a hollow optical waveguide. Based on the antiresonant reflection in the optical waveguide, we established a theoretical model to address the field enhancement in the hollow ZnO microcolumn, which systematically clarifies the influence of the geometric structure of the microcolumn on the field enhancement. We report for the first time, the enhanced emission of the near ultraviolet light (working wavelength of 385 nm) along the axial direction of the ZnO microcolumn. The corresponding microsized light emitter has also been obtained. Experiments agree well with both theoretical predictions and computer simulations based on the finite-difference time-domain method with perfectly matched layer boundary conditions. These findings provide valuable information for the application of ZnO micro- and nanostructures in optoelectronic devices.

Effect of lipoic acid combined with paclitaxel on breast cancer cells

Breast cancer is the most common gynecologic tumor globally that threatens women's health. Lipoic acid is a type of antioxidant that can alleviate oxidative stress damage. Studies showed that lipoic acid could inhibit the proliferation of tumor cells in cervical cancer and colon cancer. This paper intends to explore the combined effect of lipoic acid and paclitaxel on breast cancer cells. Breast cancer MCF-7 cells were divided into four groups: control group, lipoic acid group, paclitaxel group, and a combination group. MTT was applied to detect the drugs' influence on breast cancer cell proliferation. A colony formation test was used to determine the effects on breast cancer cell clone formation rate. Western blot was performed to detect the effects on nuclear factor (NF)-κB. Lipoic acid alone can inhibit tumor cell proliferation and clone formation with time dependence. Compared with the control, paclitaxel alone can significantly suppress tumor cell proliferation and clone formation (P < 0.05). Lipoic acid and paclitaxel in combination obviously strengthened their individual inhibitory effects on tumor cells (P < 0.05). Compared with the paclitaxel alone group, the combination group exhibited more remarkable inhibitory effect (P < 0.05). Lipoic acid alone or combined with paclitaxel can inhibit NF-κB expression and inhibit breast cancer cell proliferation.

S-phase kinase-associated protein 2 expression interference inhibits breast cancer cell proliferation

We investigated the expression of S-phase kinase-associated protein 2 (SKP2) in breast cancer tissues, and the effects of SKP2-specific small interfering RNA (siRNA) interference on breast cancer cell proliferation. Thirty subjects provided breast cancer tissue samples and 18 subjects provided normal breast specimens for this study. The expression of SKP2 in breast cancer patient tissues and normal breast tissues was detected by western blotting analysis and reverse transcription-polymerase chain reaction. SKP2-specific siRNA was used to decrease SKP2 expression in breast cancer cell line MDA-MB-231. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to detect cell proliferation. SKP2 expression in breast cancer tissues was significantly higher than in normal breast tissues (P < 0.05). Two pairs of siRNA specific to SKP2 were required to downregulate SKP2 expression in the breast cancer cell line MDA-MB-231. The MTT assay showed that MDA-MB-231 growth significantly slowed after SKP2 interference. Patients with breast cancer have an increased SKP2 level. Interference in SKP2 gene expression can inhibit breast cancer cell growth, suggesting that SKP2 is potentially a new target for breast cancer therapy.

TBX21 polymorphisms are associated with virus persistence in hepatitis C virus infection patients from a high-risk Chinese population

Hepatitis C virus (HCV) infection is a major cause of chronic liver disease and the varied outcomes of the infection depend on both viral and host factors. We have demonstrated that the HCV alternate reading frame protein (F protein) is related to Th1/Th2 bias which is involved in virus persistence in chronic hepatitis C (CHC) patients. The purpose of this study was to test the hypothesis that genetic variants of TBX21 (T cell specific T-box transcription factor) were associated with the outcomes of HCV infection and F protein generation. Three single nucleotide polymorphisms (SNPs) (rs17250932, rs2074190, rs4794067) in the TBX21 gene were genotyped in a case-control study in a cohort of a high-risk group, including 354 healthy controls and 747 CHC patients (190 anti-F protein antibody seronegative patients and 557 anti-F protein antibody seropositive patients). Results showed that the rs4794067 C allele in the TBX21 promoter was significantly more common in CHC patients (OR = 1.335, 95% CI = 1.058-1.684, P = 0.015), exceptionally in anti-F protein seropositive patients (OR = 1.547, 95% CI = 1.140-2.101, P = 0.005), compared with healthy controls. And the risk effect was also significantly high in patients with HCV 1b genotype and mild fibrosis (P = 0.021, P = 0.010, respectively). Compared with the most frequent haplotype TAT, haplotype analysis showed that the distribution of TAC was significantly different between the chronic HCV carrier group and the healthy group, and so was the anti-F antibody seronegativity group and the anti-F antibody seronegativity group (all P < 0.001). Our results suggested that TBX21 variants may be involved in the etiology of this disease.

First Report of Corynespora Leaf Spot Caused by Corynespora cassiicola on Gynura in China

Gynura (Gynura bicolor DC.) is a perennial herbaceous plant in the family Compositae. It is an important Chinese vegetable, and is commonly used as a Chinese herbal medicine. In 2010, a severe leaf spot disease was observed on gynura grown in the main production areas in Tong Nan County, Chongqing City, China. Some farms experienced 60% disease incidence. Symptoms usually began on the lower leaves, as circular to elliptical or irregular spots with concentric rings. Individual spots were dark brown with grayish centers, sometimes coalescing and leading to extensive necrosis. The fungus associated with lesions was characterized as follows: Conidiophores were single or in clusters, straight or flexuous, unbranched, percurrent, cylindrical, pale to dark brown, 87.5 to 375.0 μm long and 5.0 to 10.5 μm wide. Conidia were solitary or catenate, straight to slightly curved, obclavate to cylindrical, 3 to 14 pseudoseptate, 82.8 to 237.5 μm long and 7.0 to 7.8 μm wide, and pale brown. The morphological characteristics of the conidia and conidiophores agreed with the descriptions for Corynespora cassiicola (1). To isolate the causal pathogen, surface-sterilized tissue at the margin of lesions was immersed in 75% ethanol for 30 s, rinsed in sterile water, dried in a laminar flow bench, transferred to PDA, and incubated at 28°C. Four single-spore cultures of the isolates were obtained and named from ZBTK10110637 to ZBTK10110640. All strains were identified as C. cassiicola. The isolate ZBTK10110637 was selected as representative for molecular identification. Genomic DNA was extracted by CTAB (2). The internal transcribed spacer (ITS) region of the rDNA was amplified using primers with ITS1 (5'-TCCGATGGTGAACCTGCGG-3') and ITS4 (5'-TCCTCCGCTTATTGATATGC-3'). Amplicons were 433 bp (GenBank Accession No. JX867272) and shared 100% similarity with that of C. cassiicola (NRC2-1 No. AB539285.1). To confirm pathogenicity, four isolates were used to inoculate 12 gynura plants (6 weeks old) by mist spray-inoculation with 10⁸ spores/ml suspension in sterile distilled water on the leaves. Control plants were misted with sterile distilled water. After inoculation, all plants were incubated in a greenhouse maintained at 20 to 28°C with relative humidity of 80 to 85%. Five days after inoculation, dark brown spots with a grayish center typical of field symptoms were observed on all inoculated plants. No symptoms were seen on water-treated control plants. The fungus was re-isolated from inoculated plants. The morphological characteristics of isolates were identical with the pathogen recovered originally. This is the first report of C. cassiicola on gynura. References: (1) M. B. Ellis. CMI Mycological Papers 65(9):1-15, 1957. (2) T. J. White et al. Page 315 in: PCR Protocols: A Guide to Methods and Applications. Academic Press, San Diego, CA, 1990.

The methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism and tumor risk: evidence from 134 case-control studies

Methylenetetrahydrofolate reductase (MTHFR) is an important enzyme involved in folate metabolism, which is essential for DNA synthesis and methylation. Genetic variations in the MTHFR gene seem to contribute to a decreased activity of MTHFR, ultimately confer increased susceptibility to cancer. As the most extensively studied polymorphism, MTHFR C677T polymorphism was shown to contribute to cancer susceptibility but the results were inconsistent. The authors performed a meta-analysis including 134 studies (46,207 cases and 69,160 controls) to address the issue. Odds ratios (ORs) with corresponding 95% confidence intervals (CIs) were used to assess the association. Overall, a significant elevated risk of cancer was associated with the MTHFR C677T polymorphism in T-allele versus C-allele comparison (OR = 1.06, 95% CI 1.02-1.11, P(heterogeneity) < 0.001), homozygote model (OR = 1.08, 95% CI 1.01-1.17, P(heterogeneity) < 0.001) and dominant model (OR = 1.05, 95% CI 1.00-1.10, P(heterogeneity) < 0.001). In the stratified analyses, significantly increased cancer risks were indicated among Asians in all genetic models except for heterozygote model. Further analysis revealed that C677T was significantly associated with an increased risk of esophageal and stomach cancer. This meta-analysis supports an association between the MTHFR C677T polymorphism and increased risk of esophageal and stomach cancer, especially among Asians. Additionally, more high-quality studies and that the covariates responsible for heterogeneity should be controlled to obtain a more conclusive response about the function of MTHFR C677T in cancer.

First Report of Pseudomonas cichorii Causing Leaf Spot of Vegetable Sponge Gourd in China

A suspect bacterial leaf spot on vegetable sponge gourd (Luffa cylindrical (L.) Roem.) was found in a commercial greenhouse in Pi County, Chengdu City, Sichuan Province, China, in February 2011. Approximately 20 to 30% of plants were affected, causing serious economic loss. Symptoms occurred only on seedlings and consisted of water-soaked, irregularly shaped, black lesions on the surface and margins of cotyledons. A bacterium was consistently isolated on nutrient agar from diseased leaf tissues that had been surface disinfected in 70% ethyl alcohol for 30 s. The bacterium produced small gray colonies with smooth margins, was gram negative, fluoresced on King's B medium, and showed pectolytic activity when inoculated on potato slices. The partial sequences of 16SrRNA gene (1,377 bp) of the bacterium (GenBank Accession No. KC762217), amplified by using universal PCR primers 16SF (5'-AGAGTTTGATCCTGGCTCAG-3') and 16SR (5'-GGTTACCTTGTTACGACTT-3'), shared 100% similarity with that of Pseudomonas cichorii (GenBank Accession No. HM190228). The vegetable sponge gourd isolate was also identified by using the Biolog Microbial Identification System (version 4.2, Biolog Inc., Hayward, CA) as P. cichorii with the following characteristics (1): negative for arginine dihydrolase, gelatin liquefaction, and N₂ production. Positive reactions were obtained in tests for catalase, oxidase, potato rot, utilization of melibiose, and mannitol. Tests were negative for utilization of sucrose, trehalose, D-arabinose, raffinose, cellobiose, and rhamnose. A pathogenicity test was conducted on 4-week-old vegetable sponge gourd plants by spray-inoculation with 10⁸ CFU/ml sterile distilled water on the leaves of 15 vegetable sponge gourd plants and by needle puncture on the stems of 15 other plants with P. cichorii, respectively. Control plants were misted with sterile distilled water or punctured on the stem with a clean needle. Plants were placed in a greenhouse maintained at 28 ± 2°C with relative humidity of 80 to 85%. Symptoms, the same as seen on the original diseased plants, developed after 7 to 10 days on inoculated plants. Control plants remained healthy. The bacterium was readily re-isolated from inoculated plants and identified as P. cichorii using P. cichorii-specific primer hrpla/hrp2a (1). To our knowledge, this is the first report of P. cichorii causing disease on commercially grown vegetable sponge gourd in China. This new finding will provide the basis for developing resources for diagnostics and management, including screening varieties for resistance. References: (1) S. Mazurier et al. J. FEMS Microbiol. Ecol. 49:455, 2004. (2) N. W. Schaad et al., eds. Laboratory Guide for Identification of Plant Pathogenic Bacteria, 3rd ed. APS Press, St. Paul, MN, 2001.

Poly[diaqua-[μ6-4,4'-(1,4-phenyl-ene)bis-(2,6-dimethyl-pyridine-3,5-dicarboxyl-ato)]dilead(II)]

The asymmetric unit of the title Pb-based coordination polymer, [Pb₂(C₂₄H₁₆N₂O₈)(H₂O)₂]_n, consists of one Pb^II cation, half of a 4,4′-(1,4-phenyl­ene)bis­(2,6-dimethyl­pyridine-3,5-di­carb­oxyl­ate (L⁴⁻) ligand and one coordinating water mol­ecule. The centers of the benzene ring of the ligand and the four-membered Pb/O/Pb/O ring are located on centers of inversion. The Pb^II ion is coordinated in form of a distorted polyhedron by seven O atoms from four separate L⁴⁻ ligands and by one water O atom. The PbO₇ polyhedra share O atoms, forming infinite zigzag [PbO₄(H₂O)]_n chains along [100] that are bridged by L⁴⁻ ligands, forming a two-dimensional coordination network parallel to (001). O—H⋯O hydrogen bonds involving the water mol­ecule are observed.

ZnO nanocone: application in fabrication of the smallest whispering gallery optical resonator

ZnO semiconductors at the micro- and nanometre scales are attractive in optical, magnetic, and electronic applications because of their particular features and excellent properties. The whispering gallery mode (WGM) is a general and effective type to amplify the intensity of the luminescence emission, and has gained extensive application in lasing and microcavities. In this contribution, we reported that the smallest whispering gallery optical resonator has been achieved in an individual ZnO nanocone whose diameter gradually reduces from bottom to top in the range of 700 to 50 nm. Using the monochromatic cathodoluminescence (CL) equipment attached at a scanning electron microscopy, we observed the alternating patterns of bright and dark rings from the monochromatic CL image of an individual ZnO nanocone, which is attributed to the WGM-like enhanced luminescence emission when the ZnO nanocone is considered as an optical resonator. The smallest mode number of WGM, N=0, was observed in the ZnO nanocone with a radius of 55 nm for the considered light wavelength of 380 nm, and with a radius of 81 nm for the considered light wavelength of 500 nm, respectively. These results showed that the smallest whispering gallery optical resonator from an individual ZnO nanocone has been fabricated. Experiments are in good agreement with both theoretical predictions and computer simulations based on the finite-difference time domain method with perfectly matched layer boundary conditions. These findings provided valuable information for applications of ZnO micro- and nanostructures in optoelectronic devices.

Improved field emission properties of thiolated multi-wall carbon nanotubes on a flexible carbon cloth substrate

In this paper we report the observation of enhanced field emission properties from thiolated multi-wall carbon nanotubes (MWCNTs) produced by a simple and effective two-step chemical surface modification technique. This technique implements carboxylation and thiolation on the MWCNTs synthesized by microwave plasma chemical vapor deposition (MPCVD) on the flexible carbon cloth substrate. The resulting thiolated MWCNTs were found to have a very low threshold field value of 1.25 V µm(-1) and a rather high field enhancement factor of 1.93 × 10(4), which are crucial for applications in versatile vacuum microelectronics.

Presence of bacterial phage-like DNA sequences in commercial Taq DNA polymerase reagents

Many studies have reported the presence of bacterial DNA contamination in commercial Taq DNA polymerase reagents. This is the first report of the presence of phage-like DNA sequences in certain commercial Taq DNA polymerase reagents. Precautions are needed when using amplification reagents with exogenous DNAs.

Characterization of an IS element in Mycoplasma orale that is highly homologous to M. fermentans ISLE

In a previous study, using a primer set designed from Mycoplasma fermentans, we amplified a PCR fragment from Mycoplasma orale similar to the 206-bp DNA fragment amplified from M. fermentans insertion-sequence-like element (ISLE). The presence of this similar ISLE fragment has the potential to cause confusion in the PCR diagnosis of M. fermentans and M. orale, which have significantly different clinical scenarios. An ISLE from three different M. orale strains was amplified by using a primer set designed from sequence within the left and right terminal stem and loop (S&L) structures flanking the ISLE of M. fermentans. Sequence analysis showed that the M. orale ISLE is 93% identical to that of M. fermentans at the nucleotide level and codes for two open reading frames also found in the M. fermentans ISLE. This is the first finding that two different mycoplasma species harbor highly homologous IS elements. This finding has great significance in clinical diagnosis and suggests a possibility of horizontal transfer of an IS element between two different mycoplasma species.

The structure dependent electrochemical-response of novel 1-(4-mercaptobutyl)-4-(2-ferrocenylvinyl)pyridinium bromide SAMs on an au electrode

The 1-(4-mercaptobutyl)-4-(2-ferrocenylvinyl)pyridinium bromide (1-HS(CH2)(4)-4-[(E)-FcCH=CH]C5H4N)+Br- and its hydrogenated product [1-HS(CH2)(4)-4-(-FcCH2CH2)C5H4N]+Br- were synthesized and assembled on an Au electrode to form self-assembled monolayers which showed a structure-dependent electrochemical-response in phosphate buffer aqueous solutions (pH = 7).

[Expression and characterization of t-PA in insect cells]

With the RT-PCR technique, human tissue-type plasminogen activator (t-PA) cDNA was amplified from human melanoma cells. The sequence was proved to be the same as those reported by foreign researchers. The t-PA cDNA containing whole reading frame was inserted into the transfer vector pBacPAK8. The constructed pBac-tPA and the linear BacPAK6 virus DNA were cotransfected with Tn-5B-1 insect cells by lipofectin-mediated transfection method. Eleven pure recombinant viruses were isolated by plaque assay, and one of them, nominated BactPA3, was selected by PCR identification and biological activity comparison. The t-PA activity expressed in serum-containing media reach the highest level at 72 h postinfection. The activity was 3.04 x 10(3) IU/ml, e.g. 1.8 x 10(4) IU/10(6) cells. The highest expression level in serum-free media was almost the same, but needed more time (at 132 h postinfection). SDS-PAGE fibrin autography showed that the molecular weight of the expressed t-PA was about 68 kDa. Its stimulation by fibrinogen, affinity with fibrin and inactivation in plasma were almost the same as the native t-PA purified from human melanoma cell culture. The half-life of t-PA expressed in serum-free media was seven minutes.

[Research on improving rice resistance to the pest by B.t. and SBTi genes]

B.t. gene alone or and SBTi gene together were introduced into two elite indica rice varieties grown in South China by bombardment. And 21 independent transgenic lines containing B.t. gene and 4 independent transgenic lines containing B.t. gene and SBTi gene were obtained. Molecular and genetics analysis for R1 plants showed integration of multiple transgenes occurred at one genetic locus. Northern blot result proved B.t. gene expressed in R2 transgenic plants stably. Bioassays using R2 transgenic plants with leaf-folder (Cnaphalocrosis medinalis), indicated that transgenic rice plants are more resistant to the pest than untransformed control plants. And those transgenic plants containing B.t. and SBTi genes showed more resistance compared with those plants containing B.t. gene.

[Fertile transgenic indica rice from microprojectile bombardment of embryogenic callus]

A reproducible and efficient transformation system for indica rice was developed based on microprojectile bombardment of embryogenic callus. Sufficient globular embryogenic calli were produced within 2-6 weeks from 3-4 week old calli derived from mature embryos. The embryogenic calli were bombarded with the plasmid pFWZ16 containing bar gene and B.t. delta-endotoxin gene. Selection, pre-regeneration, regeneration and rooting were carried out on media with 2-4 mg/L Basta. Partial desiccation treatment was used to increase the efficiency of regeneration. Transformed plantlets were recovered within 4-5 months after mature seeds were plated. From 821 bombarded embryogenic calli of two elite rice varieties popularized in South China, 477 Basta resistant plants of 48 lines were obtained. Results of PCR, Southern blotting, RNA dot blotting, and topical application of Basta demonstrated that the foreign bar gene and B.t. gene were integrated into the genome of transgenic rice plants, and also expressed. 87.5% of the transgenic plants were fertile. Mendelian segregation of the foreign genes was indicated by Basta application and Southern blot analysis of R1 plants.

Mycoplasma orale has a sequence similar to the insertion-like sequence of M. fermentans

Polymerase chain reaction (PCR) using the Mycoplasma fermentans insertion sequence-like element (ISLE) RW primer set amplifies DNA from Mycoplasma orale when more than 1 ng is present in the reaction tube. In this study, amplified products from 11 different clinical isolates and the ATCC prototype of M. orale were sequenced and compared to 206 bp amplicons from eight isolates and the ATCC strain of M. fermentans. The nucleotide sequences of the amplified M. orale products had high sequence homology (88-92%) to those from M. fermentans, but differed at several key positions. The M. orale products contained a DraI restriction enzyme site not found in any of the M. fermentans amplified products. Consistent with this finding, the PCR products from M. orale were digested by DraI while the PCR products from M. fermentans were resistant to DraI digestion. The results suggest that M. orale may carry a similar IS-like element that complicates but does not negate using the ISLE PCR assay designed to detect M. fermentans. It appears possible for the RW primers to amplify M. orale if the mycoplasmas are present at higher concentrations. The amplified products can be differentiated from those from M. fermentans by a rapid DraI restriction endonuclease digestion or by Southern blot analysis using the RW006 internal probe under highly stringent conditions.

[Obtaining transgenic rice plants and their progenies using Agrobacterium tumefaciens]

Rice (Oriza sativa L.) suspension cells of Taipei 309 were co-cultivated with A. tumefaciens stran EHA101 harbouring binary vector pBYT2 for 3 days in the presence of vir inducer, 100 mumol/L acetosyringone (AS). After 2 months of continuous selection, 17 stable hygromycin-resistant, GUS-positive calli were recovered from 364 suspension cell clusters co-cultivated with A. tumefaciens. 10 putative transgenic R0 plants obtained from 8 tansformed calli and their progenies were analyzed for the integration and expression of foreign genes. Southern blot analysis of R0 and R1 generations indicated that foreign genes had been stably integrated in the genome of transgenic rice and sexually transmitted. One of the transgenic lines showed 5 copies of T-DNA integration, while the others had only one copy. Histochemical staining observation and fluorometric assay of GUS activity in transgenic rice cells and plants showed ubiquitin promoter from maize was highly effective in driving the expression of gus reporter gene in transgenic rice cells. GUS protein and its activity were also investigated through ndPAGE-X-Gluc staining assay, and it was found that the GUS protein in transgenic rice cells was smaller in size than the standard GUS protein (Sigma Co. G0786) but as large as that from E.coli HB101 (pBI121). This study suggested that Agrobacterium-mediated transformation of plant is an efficient and reliable method to introduce foreign genes into rice.

Two-dimensional Raman-Nath acousto-optic bistability by use of frequency feedback

From the frequency dependence of the optical transmission characteristics of Raman-Nath acoustic-optic diffraction, the dynamic equations and steady-state solutions of a two-dimensional Raman-Nath acousto-optic bistable system are derived. In this system, feedback is realized by use of a diffracted light beam to control the frequency of the acoustic-optic driver. The curves of light output versus input corresponding to several orders of the diffracted beams are obtained by theoretical analysis. They can all lead to bistability. The amount of hysteresis is a function of the order of the diffracted beam, the bias frequency, and the feedback coefficient. Experimental results are presented and compared with theoretical analyses.

Integration and expression of human growth hormone gene in Caladium bicolor

Human growth hormone (hGH) gene has been inserted into the plasmid pLGV1103 to give the recombinant plasmid pLB-9. It has been introduced into the agrobacterium containing plasmid pGV3850. The recombinant Ti plasmid pGL198(hGH) has been obtained by homologous recombination. The monocotyledon Caladium bicolor has been transferred with pGL198 (hGH) with the leaf-disk co-cultivation method, and transgenic plants have been regenerated. The results of nopaline analysis, NPT II detection Southern blot and Western blot show that the hGH gene was integrated into the genome of Caladium bicolor, and a 22-kD protein was synthesized in the transgenic plants.

[Classification and treatment of torsades de pointes (TdP): a report of 11 cases]

A clinical analysis of 11 cases with TdP was reported. These patients were divided into two groups: 9 cases with long QT syndrome and 2 with normal QT interval. All of the patients suffered from coronary heart disease with various concomitant ailments, such as pulmonary heart disease (1 case), atrioventricular block (5 cases with complete or type II second degree AV block), hypokalemia (7 cases). In one case the TdP was caused by aminodarone administration. The principle of treatment included removing the inducing causes, treating the primary diseases and interrupting TdP. All patients who had hypokalemia were treated with potassium chloride. 7 of 9 cases showed effective response to treatment with magnesium sulfate. The patients with long QT syndrome failed to respond with MgSO4. Severe bradycardia should be treated with isoprenaline. Only one patient had pacing therapy and another received electric conversion. According to our experience, for patients of TdP with long QT syndrome class Ia and III antiarrhythmic agents were contraindicated, but those with normal QT interval can take these drugs.

Cytotoxic activity of trewiasine in 4 human cancer cell lines and 5 murine tumors

Trewiasine (TWS) is a mytansinoid compound. It possessed a significant cytotoxic activity against various human cancer cell lines in vitro. U937 cells, which were more sensitive to the TWS, required TWS 1 microgram.ml-1 to inhibit cell growth over 90% (P less than 0.01). TWS also showed activities against murine tumors in vivo, such as the ascitic tumors S180, hepatoma, U14, and solid tumor Lewis lung carcinoma. Depression of leukocytes was not seen when mice were given ip TWS 10 or 50 micrograms.kg-1.d-1 x 7 d. TWS 0.1-1 micrograms.ml-1 caused no sister chromatid exchange induction in Chinese hamster cell line V79.

[Cytological examination of bronchoalveolar lavage fluid and its clinical significance in patients with diffuse interstitial lung diseases]

Cytological examination of bronchoalveolar lavage fluid (BALF) was carried out in 48 patients with diffuse interstitial lung diseases based on chest roentgenography. 7 cases manifested with respiratory symptoms but without any abnormality on both chest roentgenogram and fibroptic bronchoscopy served as controls. The total cell counts of BALF in the study group were all higher than those of the control group (3.1 x 10(5)/ml) and the differential count of the cells showed that neutrophilic granulocytes was found in patients with fibrosing alveolitis, Neutrophilic granulocytes accounted for 21.3 +/- 2.4% of all the cells and the percentage was significantly higher than that of the control group (1.8 +/- 0.5% P less than 0.01). On the contrary, lymphocytosis was found in patients with allergic alveolitis and sarcoidosis; lymphocytes accounted for 30.8 +/- 5.3% and 29.0 +/- 1.1% of all the cells in these two diseases respectively and the percentage was also higher than that of the control group (3.0 +/- 0.6% P less than 0.01). However, the differential cell count of BALF in alveolar carcinoma showed no significant difference with that of the control group (P greater than 0.05). The factors influencing the quality control of both BAL and cytological examination were evaluated and the clinical significance of these results was discussed.

Somatic embryogenesis and plantlet regeneration in the soybean Glycine max

A tissue culture procedure for the regeneration of somatic embryos and plantlets from somatic cells of the soybean Glycine max is described. Bean pods of soybean cv. TGM119 were immersed in liquid nitrogen for 20 minutes. Young embryos were excised from the immature seeds and cultured to form calli. Calli grown from the young embryos were incubated in liquid culture for two weeks. The liquid suspension culture was filtered to obtain single cells. The soybean cells were cultured for one month in a liquid medium in hanging drop cultures for development into proembryoids. The proembryoids were maintained on a solid growth medium for 40 days. The resultant callus tissue was transferred into MS media containing selected combinations and concentrations of 2,4-Dichlorophenoxyacetic acid, Naphthaleneacetic acid, Kinetin, Benzyladenine and Indoleacetic acid. In the presence of Benzyladenine (0.2 mg/l) and Indoleacetic acid (0.01 mg/l), globular and heart shaped somatic embryos were formed on the surface of the calli. Calli containing somatic embryos were transferred into liquid medium and incubated under low light conditions. After six months further incubation, more than 1,000 plantlets and a large number of somatic embryoids at various developmental stages were obtained per flask.