[Reappraisals of biological behaviors of PDGFRA mutant gastrointestinal stromal tumor]

Objective: To investigate the biological behavior spectrum of platelet-derived growth factor alpha receptor (PDGFRA)-mutant gastrointestinal stromal tumor (GIST), and to compare the clinical values of the Zhongshan method of benign and malignant evaluation with the modified National Institutes of Health (NIH) risk stratification. Methods: A total of 119 cases of GIST with PDGFRA mutation who underwent surgical resection at Zhongshan Hospital, Fudan University from 2009 to 2020 were collected. The clinicopathological data, follow-up records, and subsequent treatment were reviewed and analyzed statistically. Results: There were 79 males and 40 females. The patients ranged in age from 25 to 80 years, with a median age of 60 years. Among them, 115 patients were followed up for 1-154 months, and 13 patients progressed to disease. The 5-year disease-free survival (DFS) and overall survival (OS) were 90.1% and 94.1%, respectively. According to the modified NIH risk stratification, 8 cases, 32 cases, 38 cases, and 35 cases were very-low risk, low risk, intermediate risk, and high risk, and 5-year DFS were 100.0%, 95.6%, 94.3%, and 80.5%, respectively. There was no significant difference in prognosis among the non-high risk groups, only the difference between high risk and non-high risk groups was significant (P=0.029). However, the 5-year OS was 100.0%, 100.0%, 95.0% and 89.0%, and there was no difference (P=0.221). According to the benign and malignant evaluation Zhongshan method, 43 cases were non-malignant (37.4%), 56 cases were low-grade malignant (48.7%), 9 cases were moderately malignant (7.8%), and 7 cases were highly malignant (6.1%). The 5-year DFS were 100.0%, 91.7%, 77.8%, 38.1%, and the difference was significant (P<0.001). The 5-year OS were 100.0%, 97.5%, 77.8%, 66.7%, the difference was significant (P<0.001). Conclusions: GIST with PDGFRA gene mutation shows a broad range of biological behavior, ranging from benign to highly malignant. According to the Zhongshan method, non-malignant and low-grade malignant tumors are common, the prognosis after surgery is good, while the fewer medium-high malignant tumors showed poor prognosis after surgical resection. The overall biological behavior of this type of GIST is relatively inert, which is due to the low proportion of medium-high malignant GIST. The modified NIH risk stratification may not be effective in risk stratification for PDGFRA mutant GIST.

[Prevalence and influencing factors of abnormal spinal curvature in primary and secondary school students in Shandong Province in 2020]

In 2020, the prevalence of abnormal spinal curvature among 54 079 students in Shandong Province was 1.54%. The multivariate logistic regression model analysis showed that, compared with those in primary school, economically underdeveloped areas, and non-residential schools, students in middle and high schools, economically average areas, and residential schools had a higher risk of abnormal spinal curvature, with OR (95%CI) values of 2.029 (1.662-2.476), 2.746 (2.208-3.416), 2.237 (1.740-2.875) and 2.057 (1.705-2.483), respectively. Compared with those in economically underdeveloped areas, who were underweight, who had seat adjustments≤1 time per academic year, and who had physical education classes≤1 per week, students in economically developed areas, who were normal weight, overweight, and obese, who had seat adjustments≥2 times per academic year, and who had physical education classes 2-3 or≥4 per week, had a lower risk of abnormal spinal curvature, with OR (95%CI) values of 0.690 (0.521-0.915), 0.722 (0.546-0.955), 0.535 (0.389-0.735), 0.383 (0.274-0.535), 0.835 (0.711-0.980), 0.561 (0.474-0.663) and 0.491 (0.315-0.766), respectively.

[Selection strategy of pedicled axial flaps for repairing high-voltage electric burn wounds in foot and ankle]

Objective: To explore the selection strategy of pedicled axial flaps for repairing high-voltage electric burn wounds in foot and ankle. Methods: The retrospective observational research method was used. From January 2017 to December 2022, 16 patients with skin and soft tissue defects in foot and ankle after high-voltage electric burns were treated in General Hospital of Eastern Theater Command, including 11 cases of unilateral defect and 5 cases of bilateral defect. All patients were male, aged from 25 to 75 years. After thorough debridement, the area of the defect to be repaired with the flap was 5.0 cm×4.0 cm to 12.0 cm×8.0 cm. Before operation, the color Doppler ultrasound, computed tomography angiography, or digital subtraction angiography was used to fully evaluate the degree of vascular injury in the affected limb and to identify the distribution and traffic anastomosis of vascular network. Pedicled axial flaps with reliable blood supply were used to repair the wounds as soon as possible, and the area of flaps ranged from 3.0 cm×2.0 cm to 13.0 cm×8.0 cm. The wound in the donor area of flaps was repaired with split-thickness skin graft from head or medium-thickness skin graft from thigh. The flap repair of wounds in various areas of the ankle and foot was recorded. The postoperative survivals of the flaps and skin grafts were observed after surgery. The postoperative appearance of flaps and walking function of patients were followed up. At the last follow-up, the foot and ankle function was evaluated and rated using the American Association of Foot and Ankle Surgeons Ankle Posterior Foot Scoring System. Results: Two wounds in toe area were repaired with reverse dorsal pedis flaps, 3 wounds in medial ankle area and 2 wounds in heel area were repaired with medial plantar flaps, 2 wounds in anterior plantar area combined with toe area were repaired with reverse medial plantar flaps, 2 wounds in anterior plantar area combined with toe area and 5 wounds in anterior plantar area were repaired with reverse medial pedis flaps, 1 wound in toe area was combined with proper plantar digital artery flap, 1 dorsal pedis wound and 1 lateral malleolus wound were repaired with lateral supramalleolar perforator flaps, and 1 lateral malleolus wound and 1 dorsal pedis wound were repaired with sural neurovascular flap. One flap had venous reflux disorder after surgery and survived after treatment, while the other flaps and skin grafts survived completely after surgery. During the follow-up of 6 to 24 months after operation, the appearance of the flaps was good, and the walking function of patients was normal. At the last follow-up, the functional score of foot and ankle was 76 to 95, which was evaluated as excellent in 11 cases and good in 5 cases. Conclusions: According to the condition of high-voltage electric burn in foot and ankle, early and thorough debridement, preoperative imaging examination to evaluate blood vessels of the affected limb, and selection of pedicled axial flap with reliable blood supply are good methods for wound repair and related functional reconstruction of high-voltage electric burn in foot and ankle.

[Analysis of the status of occupational disease prevention and control of enterprises in mining and manufacturing industries in China in 2019]

Objective: To analyze the status of prevention and treatment of occupational diseases among mining and manufacturing industries in China in 2019, provide the scientific basis for the formulation and revision of policies and standards of prevention and treatment of occupational diseases. Methods: In May 2022, Collecting data of a project named Surveillance of Occupational Hazards in the Workplace in 2019 through the National Surveillance System for Occupational Hazards in the workplace. Compare the status of prevention and treatment of occupational diseases in 63 563 enterprises of mining and manufacturing industries among different dimensions. Results: The training rate of managers was 76.17% and that of occupational health managers was 76.97%. The rate of reporting of occupational diseases hazardous items was 67.58%, the rate of launching of the detection of occupational hazards was 57.16%, and the rate of launching of occupational health examination was 62.42%. Excluding the distribution rate of dust mask, the installation rate of various occupational prevention facilities and the distribution rate of gas mask and hearing protector were less than 80%. The differences in all the indicators among different areas, enterprise scales, economic types were statistically significant (P<0.05) . Conclusion: There are still some enterprises which are relatively weak in the ability of the prevention and treatment of occupational diseases in China. Measures such as special support, guidance and strengthen supervision should be taken towards those enterprises toimprove the awareness of prevention and treatment of occupational diseases and the level of that.

Clinical application prospects and transformation value of dental follicle stem cells in oral and neurological diseases

Since dental pulp stem cells (DPSCs) were first reported, six types of dental SCs (DSCs) have been isolated and identified. DSCs originating from the craniofacial neural crest exhibit dental-like tissue differentiation potential and neuro-ectodermal features. As a member of DSCs, dental follicle SCs (DFSCs) are the only cell type obtained at the early developing stage of the tooth prior to eruption. Dental follicle tissue has the distinct advantage of large tissue volume compared with other dental tissues, which is a prerequisite for obtaining a sufficient number of cells to meet the needs of clinical applications. Furthermore, DFSCs exhibit a significantly higher cell proliferation rate, higher colony-formation capacity, and more primitive and better anti-inflammatory effects than other DSCs. In this respect, DFSCs have the potential to be of great clinical significance and translational value in oral and neurological diseases, with natural advantages based on their origin. Lastly, cryopreservation preserves the biological properties of DFSCs and enables them to be used as off-shelf products for clinical applications. This review summarizes and comments on the properties, application potential, and clinical transformation value of DFSCs, thereby inspiring novel perspectives in the future treatment of oral and neurological diseases.

[Clinicopathological features and prognostic factors of gastric intermediate-risk gastrointestinal stromal tumor after surgical resection: a retrospective study]

Objective: To investigate the clinicopathological features, treatment and prognosis of gastric intermediate-risk gastrointestinal stromal tumor (GIST), so as to provide a reference for clinical management and further research. Methods: A retrospective observational study of patients with gastric intermediate-risk GIST, who underwent surgical resection between January 1996 and December 2019 at Zhongshan Hospital of Fudan University, was carried out. Results: Totally, 360 patients with a median age of 59 years were included. There were 190 males and 170 females with median tumor diameter of 5.9 cm. Routine genetic testing was performed in 247 cases (68.6%, 247/360), and 198 cases (80.2%) showed KIT mutation, 26 cases (10.5%) showed PDGFRA mutation, and 23 cases were wild-type GIST. According to "Zhongshan Method"(including 12 parameters), there were 121 malignant and 239 non-malignant cases. Complete follow-up data were available in 241 patients; 55 patients (22.8%) received imatinib therapy, 10 patients (4.1%) experienced tumor progression, and one patient (PDGFRA mutation, 0.4%) died. Disease-free survival (DFS) and overall survival rate at 5 years was 96.0% and 99.6%, respectively. Among the intermediate-risk GIST, there was no difference in DFS between the overall population, KIT mutation, PDGFRA mutation, wild-type, non-malignant and malignant subgroups (all P>0.05). However, the non-malignancy/malignancy analysis showed that there were significant differences in DFS among the overall population (P<0.01), imatinib treatment group (P=0.044) and no imatinib treatment group (P<0.01). Adjuvant imatinib resulted in potential survival benefit for KIT mutated malignant and intermediate-risk GIST in DFS (P=0.241). Conclusions: Gastric intermediate-risk GIST shows a heterogeneous biologic behavior spectrum from benign to highly malignant. It can be further classified into benign and malignant, mainly nonmalignant and low-grade malignant. The overall disease progression rate after surgical resection is low, and real-world data show that there is no significant benefit from imatinib treatment after surgery. However, adjuvant imatinib potentially improves DFS of intermediate-risk patients with tumors harboring KIT mutation in the malignant group. Therefore, a comprehensive analysis of gene mutations in benign/malignant GIST will facilitate improvements in therapeutic decision-making.

[Clinical significance of pathological diagnosis and genetic abnormalities detection in gastrointestinal stromal tumor using endoscopic biopsy]

Objective: To investigate the clinical significance of pathological diagnosis and genetic abnormalities detection of gastrointestinal stromal tumor (GIST) using endoscopic biopsy. Methods: Patients with GIST diagnosed by endoscopic biopsy (from January 1st, 2016 to August 1st, 2018, at Zhongshan Hospital, Fudan University) were included in this study. This retrospective study evaluated the histopathologic and immunohistochemical (IHC) features, genetic abnormalities of the tumors and the treatment and clinical course of the patients. Results: Totally 4 095 cases of GIST were collected, among which 67 patients (67/4 095, 1.6%) underwent endoscopic biopsy. Forty-eight patients (71.6%) were male and 19 (28.4%) were female, with a mean age of 61 years (range 31-90 years). Fifty-nine lesions were located in stomach and eight in duodenum. Of all the 67 cases, 47 were spindle type, 14 were epithelioid type, and 6 mixed type. IHC staining showed the positive rates were 100.0% (64/64) for DOG1, 98.4% (62/63) for CD117, 87.5% (56/64) for CD34, 3.6% (2/56) for S-100 protein, 12.1% (7/58) for α-SMA, 12.3% (7/57) for desmin and 4.0% (2/50) for CKpan. Morphologically, 34 cases were malignant; three cases (all epithelioid type) were originally misdiagnosed as poorly differentiated carcinoma; missed-diagnosis were found in four cases (spindle type) due to the insufficient diagnostic tumor cells. The genetic abnormality detection rate in the biopsy tissue was 38.8% (26/67),among them two patients were lost to follow up after biopsy, 33 patients received surgical resection, 16 cases underwent operation after neoadjuvant therapy and 16 patients with advanced disease underwent continuous imatinib therapy, with the genetic testing rate of 6.1% (2/33), 10/16 and 14/16, respectively. Conclusions: Endoscopic biopsy is a useful but rare method for the preoperative diagnosis of GIST. For majority of biopsy, accurate pathological diagnosis and auxiliary examination can be completed to guide clinical treatment. A thorough history in combination with endoscopic finding is essential to avoid misdiagnosis (epithelioid type) and missed diagnosis (spindle type) in suspicious cases. Genetic testing should be recommended in patients who will undergo targeted therapy after endoscopic biopsy, and it can provide valuable information and guidance for clinical treatment.

Virtual reconstruction of midfacial bone defect based on generative adversarial network

BACKGROUND

The study aims to evaluate the accuracy of the generative adversarial networks (GAN) for reconstructing bony midfacial defects.

METHODS

According to anatomy, the bony midface was divided into five subunit structural regions and artificial defects are manually created on the corresponding CT images. GAN is trained to reconstruct artificial defects to their previous normal shape and tested. The clinical defects are reconstructed by the trained GAN, where the midspan defects were used for qualitative evaluation and the unilateral defects were used for quantitative evaluation. The cosine similarity and the mean error are used to evaluate the accuracy of reconstruction. The Mann-Whitney U test is used to detect whether reconstruction errors were consistent in artificial and unilateral clinical defects.

RESULTS

This study included 518 normal CT data, with 415 in training set and 103 in testing set, and 17 real patient data, with 2 midspan defects and 15 unilateral defects. Reconstruction of midspan clinical defects assessed by experts is acceptable. The cosine similarity in the reconstruction of artificial defects and unilateral clinical defects is 0.97 ± 0.01 and 0.96 ± 0.01, P = 0.695. The mean error in the reconstruction of artificial defects and unilateral clinical defects is 0.59 ± 0.31 mm and 0.48 ± 0.08 mm, P = 0.09.

CONCLUSION

GAN-based virtual reconstruction technology has reached a high accuracy in testing set, and statistical tests suggest that it can achieve similar results in real patient data. This study has preliminarily solved the problem of bony midfacial defect without reference.

Association Between the Aldehyde Dehydrogenase-2 rs671 G>A Polymorphism and Head and Neck Cancer Susceptibility: A Meta-Analysis in East Asians

BACKGROUND

Aldehyde dehydrogenase-2 (ALDH2) plays an important role in the alcohol detoxification and acetaldehyde metabolism. Published studies have demonstrated some inconsistent associations between ALDH2 rs671 G>A polymorphism and head and neck cancer (HNC) risk.

METHODS

A meta-analysis was performed to provide pooled data on the association between the ALDH2 rs671 G>A polymorphism and HNC risk. Electronic databases were searched to identify relevant studies. Odds ratios and 95% confidence intervals (CIs) were used to examine the pooled effect size of each genetic model. In addition, heterogeneity test, accumulative analysis, sensitivity analysis, and publication bias were conducted to test the statistical power.

RESULTS

Thirteen publications (14 independent case-control studies) involving 10,939 subjects were selected. The stratified analysis indicated that both light/moderated drinking (e.g., GA vs. GG: OR = 1.47, 95% CI = 1.16 to 1.86, p < 0.01, I²  = 81.1%) and heavy drinking would increase HNC risk with rs671 G>A mutation (e.g., GA vs. GG: OR = 2.30, 95% CI = 1.11 to 4.77, p = 0.03, I²  = 81.9%).

CONCLUSIONS

In summary, this meta-analysis suggested that the ALDH2 rs671 G>A polymorphism may play an important synergistic effect in the pathogenesis of HNC development in East Asians.

Remediation of arsenic-contaminated paddy soil by intercropping aquatic vegetables and rice

Soil contamination by arsenic (As) is an important environmental issue globally. Intercropping of hyperaccumulators with main crop is typically applied for remediation of As-contaminated soil. Most hyperaccumulators are wild plants with small biomass and slow growth rates. Thus, remediation is slow. Here, we propose an effective intercropping system for remediation of As-contaminated paddy soil. Four treatments-intercropping with water spinach (Ipomoea aquatica Forsk) (T1), water celery (Oenanthe javanica (Blume) DC.) (T2), or Guangdong white arrowhead (Sagittaria sagittifolia L. var) (T3), with rice (Oryza sativa L.) monoculture (control, CK)-were used. Compared with the CK, grain yield per plant of rice under T1 and T2 increased by 58.13% and 10.48%, respectively, but decreased by 46.90% in T3. As concentration, bioaccumulation factor, and translocation factor in brown rice were significantly lower in the intercropping treatments than in CK. As removal by water spinach was 7.04 and 1.47 times that by water celery and arrowhead, respectively. The pH of paddy soil was significantly higher in all treatments than in CK, and iron plaque on rice roots under T1 and T2 decreased significantly but increased significantly under T3 compared with that of CK. Rice intercropped with water spinach had the best remediation effect. Novelty Statement: We believe that the following highlights of this manuscript will make it interesting to general readers of this journal.First, in recent years, many articles about intercropping system for the remediation of soil heavy metal pollution focus on dry land, and few studies have focused on paddy soil. The present study was on arsenic-contaminated paddy soil remediation.Second, water spinach, water celery, and arrowhead have great potential for phytoremediation. Studies have shown that these three aquatic vegetables play a role in the removal of certain pollutants, such as heavy metals. Moreover, when intercropped with rice, they can effectively increase rice yield and reduce rice diseases and insect pests. However, studies on remediation of arsenic-contaminated soil by intercropping aquatic vegetables and rice have not been reported. We propose here a rice-aquatic vegetables (water spinach, water celery and arrowhead) intercropping pattern for remediation of arsenic in soil.Third, according to the arsenic concentration and removal rate, we used a bioaccumulation factor, translocation factor, and arsenic removal per unit area of plants for the quantitative evaluation of the remediation effects of the intercropping systems. We found that the intercropping of rice and water spinach could be used to remediate arsenic-contaminated soil. Moreover, the extraction contents of arsenic using intercropping with water spinach was higher than that achieved in a previous study that applied intercropping with the arsenic hyperaccumulator Pteris vittata over the same growth time. This study provides a reference for realizing both remediation and increased production in arsenic-contaminated soil and for promoting sustainable development of agriculture.

[Genotypes and phenotypes of nine Uygur children with osteogenesis imperfecta in Xinjiang]

Objective: To explore the genotypes and phenotypes of osteogenesis imperfecta (OI) in Xinjiang Uygur children. Methods: The history of nine Uygur children with OI who were hospitalized in First Affiliated Hospital of Xinjiang Medical University from January 2013 to December 2017 were retrospectively reviewed. They were classified into 4 types according to the classical Sillence classification. The genes associated with OI were detected, and the pathogenic variation was assessed by InterVar and Alamut software according to the American College of Medical Genetics and Genomics (ACMG) recommendations. The phenotypes of children with different genotypes were further analyzed. Results: Nine cases aged 3 years and 6 monthes to 15 years were all clinically diagnosed as OI, the clinical manifes tations were repeated fractures, skeletal deformities,short stature, blue sclera, abnormol hearing, hypoplasia of dentin, and relaxation of Joint ligaments, among whom 6 was type Ⅲ OI, 3 were type Ⅳ OI. Nine mutations in 3 genes (COL1A1, COL1A2, and SERPINF1) were detected, and 5 of them were first reported and were all pathogenic variations. Conclusions: The cinical phenotypes of osteogenesis imperfecta in Xinjiang Uygur are complex and varied, but all of them have fractures and skeletal deformities. Genotype is different from that reported at China and abroad, and the SERPINF1 gene may have a higher incidence in Uyghur population. The genetic heterogeneity and unique gene variation pedigree of Uyghur osteogenesis imperfecta defects further provide a basis for the correlation between genotype and phenotype of osteogenesis defects.

[Clinical observation of five pediatric-type follicular lymphoma in adult]

目的

探讨成人儿童型滤泡淋巴瘤（PTFL）患者的病理诊断、临床特征、治疗及转归特点。

方法

回顾性分析在江苏省人民医院就诊的5例成人PTFL患者的临床病理特点、实验室检查、诊治经过及随访结果，并结合文献进行综述。

结果

5例PTFL患者均为成年发病，中位年龄22（15~33）岁。起病时表现为局部无痛性淋巴结肿大，无发热、盗汗、消瘦等全身B症状。组织病理表现为典型的大滤泡结构，增殖指数高，存在免疫球蛋白重链基因克隆性重排，组化提示无BCL-2蛋白表达，荧光原位杂交未见BCL-2基因异常。所有患者均为Ⅰ~Ⅱ期，治疗仅通过局部肿块切除，未追加局部放疗或全身系统性免疫化疗。中位随访27个月，5例患者均处于持续缓解状态。

结论

成人PTFL病理增殖指数较高，无BCL-2表达和基因异常，临床多为局限病变，通过局部手术治疗预后较好，与经典成人滤泡淋巴瘤有显著差异。

Genome-wide analysis of differentially expressed lncRNA in sporadic parathyroid tumors

Diagnosis of parathyroid carcinoma on histological examination is challenging. Thousands of differentially expressed lncRNAs were identified on the microarray data between parathyroid cancer and adenoma samples. Four lncRNAs were significantly dysregulated in further validation. The "lncRNA score" calculated from these lncRNAs differentiated parathyroid carcinomas from adenomas. LncRNAs serve as biomarkers for parathyroid cancer diagnosis.

INTRODUCTION

Diagnosis of parathyroid carcinoma (PC) on histological examination is challenging. LncRNA profile study was conducted to find diagnostic biomarkers for PC.

METHODS

LncRNA arrays containing 91,007 lncRNAs as well as 29,857 mRNAs were used to assess parathyroid specimen (5 carcinomas and 6 adenomas). Bioinformatics analyses were also conducted to compare the microarray results between parathyroid carcinomas and adenomas (PAs). Differentially expressed lncRNAs of 11 PCs and 31 PAs were validated by real-time quantitative PCR.

RESULTS

On the microarray data between PC and PA samples (fold change ≥ 2, P < 0.05), 1809 differentially expressed lncRNAs and 1349 mRNAs also were identified. All carcinomas were clustered in the same group by clustering analysis using dysregulated lncRNAs or mRNAs. Four lncRNAs (LINC00959, lnc-FLT3-2:2, lnc-FEZF2-9:2, and lnc-RP11-1035H13.3.1-2:1) identified were significantly dysregulated in further RT-PCR validation. The global "lncRNA score" calculated from the lncRNAs above also differentiated parathyroid carcinomas from adenomas.

CONCLUSIONS

LncRNA profiling shows distinct differentially expressed lncRNAs in parathyroid neoplasm. They may play a key role in parathyroid cancer and serve as potential biomarkers to distinguish parathyroid cancers from parathyroid adenomas.

[Clinical and genetic features of Chinese kindreds with Van der Woude syndrome caused by interferon regulatory factor 6 mutation]

OBJECTIVE

This study aimed to investigate the clinical phenotype and genetic characteristics of Chinese families with Van der Woude syndrome (VWS).

METHODS

Clinical manifestations between 14 families and within each family were recorded. Possible inheritance modes and pathogenic genes were analyzed. Phenotypic distribution and gene frequencies were calculated.

RESULTS

Of the pedigrees investigated, an autosomal dominant inheritance pattern was suggested. All patients had typical symptoms. The pathogenic gene was interferon regulatory factor 6 (IRF6). Phenotypic distribution frequencies were as follows: lip pits (91.9%), cleft lip and/or palate (73.0%), and hyperdontia (8.1%). There were significant differences in clinical phenotypes among individuals of different families and individuals of the same family.

CONCLUSIONS

VWS in a Chinese population was dominantly inherited with high penetrance and variable expressivity. The pathogenic gene was IRF6. VWS in a Chinese population was genotyped as VWS1.

[Abuse of diphenoxylate and related factors of forced drug abstainer in Gansu province]

Objective: To investigate the prevalence of diphenoxylate abuse and related factors of forced drug abstainer in Gansu province. Methods: By using a self-designed questionnaire, an epidemiologic investigation was carried out among 2 108 forced drug abstainer selected from the compulsory isolation detoxification center of Gansu province. A case-control study was conducted to analyze the factors related with diphenoxylate abuse. Results: The diphenoxylate abuse rate among forced drug abstainer in Gansu was 19.8% (406/2 046), ranking first in medical drug abuse. Multiple logistic regression analysis showed that factors as relieving withdrawal symptoms (OR=2.08, 95%CI: 1.01- 4.32), ways to obtain diphenoxylate (other ways: OR=1.00; regular clinic: OR=27.67, 95%CI: 2.64-289.82; friend: OR=0.01, 95%CI: 0.01-0.03), degree of euphoria (high: OR=1.00; medium: OR =3.36, 95%CI: 1.18-9.55; low: OR=26.16, 95%CI: 10.30-66.42), years of drug abuse (<5 years: OR=1.00; 10-15 years: OR=2.48, 95%CI: 1.02-6.04), abuse at home or in friend's house (OR=3.04, 95%CI: 1.08-8.68), abuse in car (OR=0.05, 95%CI: 0.00-0.68) and detoxification for the first time (OR=0.61, 95%CI: 0.43-0.86) were the possible influencing factors for diphenoxylate abuse. Conclusions: The prevalence of diphenoxylate abuse in forced drug abstainer in Gansu was relatively high. Reasons of abusing, the way to obtain diphenoxylate, whether using drug together with friends, degree of euphoria, years of abuse, abuse place and times for detoxification were related factors influencing the abuse of diphenoxylate.

Vascular endothelial growth factor polymorphisms are associated with osteosarcoma susceptibility

Polymorphisms in the vascular endothelial growth factor (VEGF) gene may contribute to osteosarcoma risk, but the results of previous studies have been inconsistent and inconclusive. We conducted a meta-analysis to assess this association more accurately. Relevant studies were collected systemically from three online English databases. Crude odds ratios (ORs) and 95% confidence intervals (CIs) were used to assess the strength of the associations of three VEGF gene polymorphisms (+936C/T, '634 G/C, +1612 G/A) with osteosarcoma risk. Seven case-control studies involving 1,350 cases and 1,706 controls were selected for the meta-analysis. The pooled OR indicated that the VEGF +936C/T polymorphism was associated with increased risk of osteosarcoma in a Chinese population (T vs. C: OR = 1.26, 95% CI = 1.12–1.42, P < 0.01; TT vs. CC: OR = 1.70, 95% CI = 1.29–2.24, P < 0.01; CT + TT vs. CC: OR = 1.23, 95% CI = 1.06–1.44, P < 0.01; TT vs. CC + CT: OR = 1.61, 95% CI = 1.23–2.10, P < 0.01). A significant association was also found between the −634 G/C polymorphism and osteosarcoma risk (C vs. G: OR = 0.81, 95% CI = 0.69-0.96, P = 0.01; CC vs. GG: OR = 0.66, 95% CI = 0.48–0.90, P < 0.01; GC + CC vs. GG: OR = 0.80, 95% CI = 0.67–0.96, P = 0.02; CC vs. GG + GC: OR = 0.72, 95% CI = 0.60–0.86, P < 0.01). In sum, our meta-analysis suggests VEGF polymorphisms are associated with osteosarcoma susceptibility in the Chinese population. However, further studies that include different ethnicities and larger populations are needed.

Significant association between Let-7-KRAS rs712 G > T polymorphism and cancer risk in the Chinese population: a meta-analysis

Association between let-7-KRAS rs712 polymorphism and cancer risk was inconsistent. We therefore conducted this meta-analysis to clarify the association between let-7-KRAS rs712 polymorphism and cancer risk with STATA 14.0 software. A systemic literature search in online databases (PubMed, Embase, CNKI and Wanfang database) was preformed to obtain relevant articles. A total of 13 case-control studies involving 3,453 patients and 4,470 controls were identified up to May 16, 2015. The pooled results indicated that significantly increased risk were observed in Chinese population in T vs. G (OR = 1.21, 95% CI = 1.03–1.42) and TT vs. GG + GT genetic models (OR = 1.69, 95% CI = 1.17–2.42). Sensitivity analysis was conducted and the result without heterogeneity showed significant associations in all five genetic models. Subgroup analyses of cancer type indicated a similar result in digestive cancer (for T vs. G: OR = 1.41, 95% CI = 1.26–1.57; GT vs. GG: OR = 1.24, 95% CI = 1.07–1.43; TT vs. GG: OR = 2.53, 95% CI = 1.86–3.44; GT + TT vs. GG: OR = 1.36, 95% CI = 1.19–1.56; TT vs. GG + GT: OR = 2.35, 95% CI = 1.73–3.19). In summary, these evidences demonstrate that let-7-KRAS rs712 G > T polymorphism might be associated with digestive system cancer risk in the Chinese population.

[Acute effect of ambient air pollution on small airway lung functions among school children in Shanghai]

Objective: To study the acute effects of compound ambient air pollution on small airway lung functions among school children in Shanghai. Method: A longitudinal survey on lung functions was conducted among 233 school-children from three schools (A, B and C, located in innerring, mid-ring and outer-ring areas). Lung function test was performed once a week for 3 times respectively, among children in school A and B in Dec. 2013 and in school C in Dec. 2014. The fourth lung function test was tested in Jun. 2014 and May 2015 in the respective schools. Results: from the lung function would include items as: forced mid-expiratory flow at 25% of forced vital capacity (MEF(25%)), mid-expiratory flow at 50% of forced vital capacity (MEF(50%)), mid-expiratory flow at 75% of forced vital capacity (MEF(75%)) and mid-expiratory flow between 25% and 75% of the forced vital capacity (FEF(25%-75%)). Data regarding the daily air quality real-time of PM(2.5), PM(10), SO(2) and NO(2) in Dec. 2013, Dec. 2014, Jun. 2014 and May. 2015 from the three environmental monitoring spots and meteorological data from the Shanghai Meteorological Service system which were physically close to the three schools, were collected simultaneously. Linear mixed effect model was used to examine the levels of correlation between lung function indicators and ambient air pollutants. Results When confounding factors on meteorology and individuals were controlled, the lag effects and accumulated lag effects were found to have existed between the internal quarter rang (IQR) concentration of PM(2.5) and PM(10) in lag2 day and lag02 days, IQR concentration of SO(2) in lag02 day and IQR concentration of NO(2) lag0 day, when small airway lung functions like MEF(25%), MEF(50%), MEF(75%) and FEF(25%-75%)(P<0.05) were inspected. Results from the two air pollutants model analysis showed that SO(2) and NO(2) presenting interactive effects with PM(2.5), PM(10) and lag effects more significant than the individual SO(2) and NO(2), respectively (P<0.05). Conclusion: Contents on the ambient air pollutants as PM(2.5), PM(10), SO(2) and NO(2) were negatively associated with the lung functions in the small airways of children, in Shanghai.

Role of interleukin-4 genetic polymorphisms and environmental factors in the risk of asthma in children

Asthma is an allergic disease characterized by hyperresponsiveness and chronic inflammation of the airway. The interleukin-4 (IL-4) gene and its single nucleotide polymorphisms are associated with asthma susceptibility in children. A case-control study was performed to evaluate the relationship between asthma risk and the IL-4 rs2243250 (589 C/T) and rs2070874 (107 T/C), and IL-4 receptor (IL-4R) rs1801275 (576 Q/R) polymorphisms in 317 childhood asthma patients and 351 healthy children as controls. Polymerase chain reaction amplification and sequencing was performed. The effects of interactions between the genes of interest and environmental factors were also analyzed. IL-4 rs2243250 and rs2070874 allele and genotype frequencies did not significantly differ between the asthma and control groups (P > 0.05), but those of IL-4R rs1801275 did (P < 0.05). The RR genotype and R allele of this IL-4R variant were significantly associated with asthma risk, with odds ratios (ORs; and 95% confidence intervals) of 2.97 (2.08-4.25) and 2.99 (2.32-3.85), respectively. Logistic regression analysis showed that the IL-4R 576 Q/R RR genotype demonstrated a positive interaction with environments associated with smoking or pets in its effect on asthma risk, with ORs of 2.18 (P = 0.02) and 2.29 (P = 0.01), respectively. Our results suggest that the IL-4R rs1801275 polymorphism is associated with childhood asthma, and the RR genotype confers a high risk of developing this condition. This variant exhibited positive interactions with environments in which smoking or pets were present in increasing the risk of childhood asthma.

Phylogenetic analysis of the Mongolian gerbil (Meriones unguiculatus) from China based on mitochondrial genome

Meriones unguiculatus (Gerbillinae, Rodentia) is widely used as an animal model of human disease. Here, we provide the first report of the complete mitochondrial genome sequence of M. unguiculatus (GenBank accession Nos. KF425526 and NC_023263). The sequence contained the conserved vertebrate pattern of 13 protein-coding genes, 2 ribosomal RNAs, 22 transfer RNAs, and 1 major noncoding region. We identified one extended termination-associated sequence and one conserved sequence block in the non-coding region. The putative origin of replication for the light strand (O_L) was 35 bp long. The O_L stem and adjacent sequences were highly conserved, but the loop region differed from those of other rodent species. Base composition and codon usage of the 13 protein-coding genes in M. unguiculatus were compared with those of 23 rodent species with previously sequenced mitochondrial genomes. An A+T content of 63.0% was present in M. unguiculatus; this is similar to the Murinae average (62.4 ± 0.8%) and falls between the average for Mus musculus (63.1 ± 0.1%) and Rattus sp (61.7 ± 0.4%). The AT and GC skew values of M. unguiculatus were 0.035 and -0.28, respectively, similar to those of Cricetinae species (0.057 ± 0.05 and -0.31 ± 0.05). The codon families exhibited similar abundance in all 24 species. Analysis of phylogenetic relationships with 23 other rodent species using neighbor-joining and maximum likelihood protocols and the 12 protein-coding regions on the H strand showed that M. unguiculatus should be classified as genus Meriones, sub-family Gerbillinae, family Muridae.

[Measurement and analysis of hand-transmitted vibration of vibration tools in workplace for automobile casting and assembly]

OBJECTIVE

To investigate the features of hand-transmitted vibration of common vibration tools in the workplace for automobile casting and assembly.

METHODS

From September to October, 2014, measurement and spectral analysis were performed for 16 typical hand tools(including percussion drill, pneumatic wrench, grinding machine, internal grinder, and arc welding machine) in 6 workplaces for automobile casting and assembly according to ISO 5349-1-2001 Mechanical vibration-Measurement and evaluation of human exposure to hand-transmitted vibration-part 1: General requirements and ISO 5349-2-2001 Mechanical vibration-Measurement and evaluation of human exposure to hand-transmitted vibration-Part 2: Practical guidance for measurement in the workplace.

RESULTS

The vibration acceleration waveforms of shearing machine, arc welding machine, and pneumatic wrench were mainly impact wave and random wave, while those of internal grinder, angle grinder, percussion drill, and grinding machine were mainly long-and short-period waves. The daily exposure duration to vibration of electric wrench, pneumatic wrench, shearing machine, percussion drill, and internal grinder was about 150 minutes, while that of plasma cutting machine, angle grinder, grinding machine, bench grinder, and arc welding machine was about 400 minutes. The range of vibration total value(ahv) was as follows: pneumatic wrench 0.30~11.04 m/s(2), grinding wheel 1.61~8.97 m/s(2), internal grinder 1.46~8.70 m/s(2), percussion drill 11.10~14.50 m/s(2), and arc welding machine 0.21~2.18 m/s(2). The workers engaged in cleaning had the longest daily exposure duration to vibration, and the effective value of 8-hour energy-equivalent frequency-weighted acceleration for them[A(8)] was 8.03 m/s(2), while this value for workers engaged in assembly was 4.78 m/s(2). The frequency spectrogram with an 1/3-time frequency interval showed that grinding machine, angle grinder, and percussion drill had a high vibration acceleration, and the vibration limit curve was recommended for those with a frequency higher than 400 min/d.

CONCLUSION

The workers who are engaged in cleaning, grinding, and a few positions of assembly and use grinding machine, angle grinder, internal grinder, and percussion drill are exposed to vibrations with a high vibration acceleration and at a high position of the frequency spectrum. The hand-transmitted vibration in the positions of cutting, polishing, and cleaning in automobile casting has great harm, and the harm caused by pneumatic wrench in automobile assembly should be taken seriously.

Novel ultra-thin near-eye augmented-view device (UNAD)

The current augmented-view device for glaucoma patients are limited by the low angle minification (less than 3X), image overlapping and pupil mismatching. We present a novel ultra-thin near-eye augmented-view device (UNAD) with a proper minification angle of 4X to avoid scanning eye movements. The device is realized by one symmetrical ultra-thin off-axis eight-mirror reversed telescopic optical system (field-of-view (FOV): x:-34°~3°; y: -5°~-20°, 5°~20°) and one central un-minified optical system (FOV: -5°~5°), and hence, the system can achieve a FOV (x:-34°~3°; y: -20°~20°) without overlapping images. Furthermore, the device fully accounts for pupil matching with the entrance pupil of the human eye. Finally, the simulation results in CODE V and LightTools verify that our proposed system is feasible and has potential practical value for glaucoma patients.

Development of novel DNA markers for genetic analysis of grey hamsters by cross-species amplification of microsatellites

The grey hamster has been used in biomedical research for decades. However, effective molecular methods for evaluating the genetic structure of this species are lacking, which hinders its wider usage. In this study, we employed cross-amplification of microsatellite loci of species within the same genus by polymerase chain reaction. Loci screened included 107 from the Mongolian gerbil (MG) and 60 from the Chinese hamster (CH); of these, 15 polymorphic loci were identified for the grey hamster. Of the 167 loci screened, 95 (56.9%) with clear bands on agarose gel were initially identified. After sequencing, 74 (77.9%) of these matched the criteria for microsatellite characteristics, including 41 from MG and 33 from CH. Lastly, 15 (20.3%) loci with more than two alleles for each locus were identified through capillary electrophoresis scanning. To justify the applicability of the 15 grey hamster loci, genetic indexes of grey hamsters were evaluated using 46 generations of outbred stock, established 20 years ago, from Xinjiang, China. Mean effective allele numbers and expected heterozygosity of stock were as low as, respectively, 1.2 and 0.14; these were 2.8 and 4.0 times inferior, respectively, to wild grey hamsters. This finding suggests that the genetic structure of the stock-bred population is too weak to resist artificial and natural selection, mutation and genetic drifting. In conclusion, we have developed de novo microsatellite markers for genetic analysis of the grey hamster, providing data and methodology for the enrichment of a genetic library for this species.

Selection of an effective microsatellite marker system for genetic control and analysis of gerbil populations in China

Although gerbils have been widely used in many areas of biological research over many years, there is currently no effective genetic quality control system available. In the present study, we sought to establish a microsatellite marker system for quality control and conducted an optimized analysis of 137 microsatellite loci in two laboratory gerbil populations and one wild population. Independent sample t-tests on the mean effective allele number, mean of Shannon's information index, and mean HE suggested that 28 of the 137 microsatellite markers were informative for gerbil genetic control. Analysis of 4 laboratory gerbil populations and 1 wild population using the 28 microsatellite loci indicated that allele numbers varied from 1.9639 (Guangzhou, GZ) to 6.6071 (North-West wild, NW). The average of HO versus HE was 0.6236/0.3802, 0.6671/0.4159, 0.4185/0.3464, 0.4592/0.3821, and 0.3972/0.4167 for the Beijing, NW, Hangzhou, Dalian, and GZ populations, respectively. The GZ population showed the greatest differentiation, having higher RST and Nei's standard genetic distances. An AMO-VA revealed high genetic differentiation among the five populations (FST = 0.296). The microsatellite system established here is effective and will be important in future studies for genetic quality control and monitoring of gerbil breeds.

Significant association between functional microRNA polymorphisms and head and neck cancer susceptibility: a comprehensive meta-analysis

Molecular epidemiological studies have showed a closer association between microRNA polymorphisms with and head and neck cancer (HNC) risk. But the results of these studies were inconsistent. We performed this meta-analysis to clarify the associations between microRNA polymorphisms and HNC risk. Four electronic databases (PubMed, Embase, CNKI, and Wanfang) were searched. Odds ratios (ORs) with 95% confidence interval (CIs) were calculated to assess the association between microRNA-146a rs2910164 G > C, microRNA-196a2 rs11614913 C > T, microRNA-149 rs2292832 C > T, microRNA-499 rs3746444 A > G polymorphisms and HNC risk. Heterogeneity, publication bias and sensitivity analysis were conducted to guarantee the statistical power. Overall, 11 selected articles involving 16100 subjects were included in this meta-analysis. Significantly increased risk between microRNA-146a rs2910164 G > C polymorphism and HNC risk were observed in Caucasian population (GC vs. GG: OR = 1.31, 95%CI = 1.01–1.68; GC + CC vs. GG: OR = 1.26, 95%CI = 1.02–1.57). For microRNA-196a2 rs11614913 C > T, similarly increased risk were also found in Asian population (T vs. C, OR = 1.14, 95%CI = 1.04–1.25; TT vs. CC, OR = 1.33, 95%CI = 1.09–1.61; CT + TT vs. CC OR = 1.32, 95%CI = 0.99–1.76; TT vs. CC + CT, OR = 1.14, 95%CI = 0.99–1.33). In addition, no significant association was detected between microRNA-149 rs2292832 C > T and microRNA-499 rs3746444 A > G polymorphism and HNC risk. This meta-analysis demonstrates that microRNA polymorphisms are associated with HNC development based on ethnicity diversity.

Selected representative microsatellite loci for genetic monitoring and population structure analysis of miniature swine

To optimize the combination of microsatellite loci for genetic control of outbred swine stocks, 32 of 100 loci distributed among almost all chromosomes (except 12) were screened out by 1.5% agarose, 8% polyacrylamide gel and capillary electrophoresis scanning among 3 miniature swine outbred stocks, namely Bama (BM), Guizhou (GZ) and Tibeta (TB). The mean total and effective allele numbers among these stocks were 12.1 and 5.9, respectively. The mean heterozygosity for these breeds was 0.5428, 0.6978 and 0.7646, and polymorphism information content was 0.5469, 0.7296 and 0.7663, respectively. Accordingly, hereditary variation from low to high was BM < GZ < TB. This showed that the genetic relationship between BM and GZ pigs was closer, and both were distant from TB. Additionally, the effectiveness of the 32-locus combination for evaluation of genetic quality was demonstrated in Changchun-junmo-1 (CJ-1), a standard outbred Chinese pig stock, in which the mean total and effective allele numbers and mean heterozygosity were 6.1613, 3.8483 and 0.6903, respectively. Since our results were consistent with the breeding pedigrees, the 32 loci could be used for both genetic monitoring within the individual outbred miniature swine stocks and population structure analysis between them.

Selecting representative microsatellite loci for genetic monitoring and analyzing genetic structure of an outbred population of orange tabby cats in China

We optimized a panel of microsatellite markers from cat and tiger genetic data for efficient genetic monitoring and used it to analyze the genetic structure of an outbred cat stock in China. We selected a set of rich polymorphic microsatellite loci from 131 cat microsatellite loci and 3 Sumatran tiger microsatellite loci using agarose gel electrophoresis. Next, the set of optimized genetic markers was used to analyze the genetic variation in an outbred population of orange tabby cats in China by simple-tandem repeat scanning. Thirty-one loci rich in polymorphisms were selected and the highest allele number in a single locus was 8. Analysis of the orange tabby cat population illustrated that the average observed number of alleles, mean effective allele number, mean Shannon's information index, mean expected heterozygosity, and observed heterozygosity were 3.8387, 2.4027, 0.9787, 0.5565, and 0.5528, respectively. The 31 microsatellite markers used were polymorphic and suitable for analyzing the genetic structure of cats. The population of orange tabby cats was confirmed to be a well-outbred stock.

Transferability of retrotransposon primers derived from Persimmon (Diospyros kaki Thunb.) across other plant species

Retrotransposon-based molecular markers are powerful molecular tools. However, these markers are not readily available due to the difficulty in obtaining species-specific retrotransposon primers. Although recent techniques enabling the rapid isolation of retrotransposon sequences have facilitated primer development, this process nonetheless remains time-consuming and costly. Therefore, research into the transferability of retrotransposon primers developed from one plant species onto others would be of great value. The present study investigated the transferability of retrotransposon primers derived from 'Luotian-tianshi' persimmon (Diospyros kaki Thunb.) across other fruit crops, as well as within the genus using inter-retrotransposon amplified polymorphism molecular marker. Fourteen of the 26 retrotransposon primers tested (53.85%) produced robust and reproducible amplification products across all fruit crops tested, indicating their applicability across plant species. Four of the 13 fruit crops showed the best transferability performances: persimmon, grape, citrus, and peach. Furthermore, similarity coefficients and UPGMA clustering indicated that these primers could further offer a potential tool for germplasm differentiation, parentage identification, genetic diversity assessment, classification, and phylogenetic studies across a variety of plant species. Transferability was further confirmed by examining published primers derived from Rosaceae, Gramineae, and Solanaceae. This study is one of the few currently available studies concerning the transferability of retrotransposon primers across plant species in general, and is the first successful study of the transferability of retrotransposon primers derived from persimmon. The primers presented here will help reduce costs for future retrotransposon primer development and therefore contribute to the popularization of retrotransposon molecular markers.

[Purification and characterization of L-amino acid oxidase from Agkistrodon halys pallas venom]

L-amino acid oxidase (LAO, EC 1.4.3.2) is widely found in snake venoms and is thought to contribute to the toxicity in envenoming. By using of Sephadex G-150, DEAE-Sepharose CL-6B and FPLC Superose 12 chromatography, a protein with L-amino acid oxidase activity was purified and characterized from Agkistrodon haly Pallas venom. Its molecular mass was 57 kD as determined by SDS-PAGE analysis under both reducing and non-reducing conditions, and its pI was about 4.9. The protein catalysed the stereospecific oxidative deamination of L-amino acid substrate. It inhibited the platelet aggregation induced by ADP and collagen dose-dependently, even at low concentrations of 0.2 micromol/L and 0.08 micromol/L, respectively. The LAO had antibacterial effect to E.coli K12D31, and the effective concentration was as low as 0.03 g/L. Furthermore, the LAO showed cytotoxicity in crystal violet assay and apoptosis-inducing activity in the A549 cells. After 24h treatment with 5 mg/L LAO, the typical DNA fragmentation pattern of apoptotic cells was observed by using of agrose gel electrophoresis.

Bilinexin, a snake C-type lectin from Agkistrodon bilineatus venom agglutinates platelets via GPIb and alpha2beta1

A new snake protein, named bilinexin, has been purified from Agkistrodon bilineatus venom by ion-exchange chromatography and gel filtration chromatography. Under non-reducing conditions it has a mass of 110 kDa protein on SDS-PAGE. On reduction, it can be separated into five subunits with masses in the range 13-25 kDa. The N-terminal sequences of these subunits are very similar to those of convulxin or the alboaggregins, identifying bilinexin as a new member of the snake C-type lectin family, unusual in having multiple subunits. Bilinexin agglutinates fixed platelets. washed platelets and platelet rich plasma (PRP) without obvious activation (shape change) as confirmed by light microscope examination. Both inhibitory and binding studies indicate that antibodies against alpha2beta1 inhibit not only platelet agglutination induced by bilinexin, but also bilinexin binding to platelets. VM16d, a monoclonal anti-GPIbalpha antibody, completely inhibits platelet agglutination induced by bilinexin, and polyclonal antibodies against GPIbalpha prevent its binding to platelets. However, neither convulxin, polyclonal anti-GPVI antibodies, nor GPIIb/IIIa inhibitors affect its binding to and agglutination of platelets. Bilinexin neither activates GPIIb/IIIa integrin on platelets nor induces tyrosine phosphorylation of platelet proteins, nor increases intracellular Ca2+ in platelets. Like alboaggregin B, bilinexin agglutinates platelets, which makes it a good tool to investigate the differences in mechanism between snake C-type lectins causing platelet agglutination and those that induce full activation.

Multifunctional snake C-type lectins affecting platelets

Snake venoms contain a wide range of components, many of which affect haemostasis by activation or inhibition of platelets or coagulation factors. They can be classified into groups based on structure and mode of action. One group is the snake C-type lectins, so called because of the typical folding which closely resembles that found in classical C-type lectins, such as selectins and mannose-binding proteins. Unlike the classic C-type lectins, those from snakes are generally heterodimeric with two subunits, alpha and beta. Some are multimeric heterodimers. The subunits have homologous sequences and are generally linked by a disulphide bond as well as by swapping loops. One of the first C-type lectins with a defined function was echicetin which was demonstrated to bind to platelet GPIb and block several functions of this receptor. Since then, many proteins with similar structure have been reported to act on platelet receptors or coagulation factors and several have been crystallized. These proteins were thought to be specific for a single platelet receptor or coagulation factor, i.e. they had only one receptor per heterodimer. Recent studies show that most of these C-type lectins have binding sites for more than one ligand and have complex mechanisms of action.

Preparation and characterization of hCG-loaded polylactide or poly(lactide-co-glycolide) microspheres using a modified water-in-oil-in-water (w/o/w) emulsion solvent evaporation technique

A modified w/o/w emulsion solvent evaporation technique was adopted to prepare human Chorionic Gonadotropin (hCG)-loaded polylactide (PLA) or poly(lactide-co-glycolide) (PLGA) microspheres. The effects of preparative parameters, such as stirring rate, polymer MW and concentration, and the composition of both the inner aqueous phase and oil phase etc., on hCG entrapment efficiency and microsphere characteristics were investigated. It was found that by adding 20% glycerol into the inner aqueous phase and 40% acetone into the oil phase, smooth microspheres approximately 1 microm in diameter could be produced with high hCG entrapment efficiency (>90%). In vitro release test showed a burst release of hCG from PLGA (75:25) microspheres, followed by sustained release of 55% hCG over 2 months. The initial hCG burst from PLGA microspheres increased with the glycerol concentration in the inner aqueous phase, but decreased to a low value (ca. 20%) with the addition of acetone into the oil phase, which could be attributed to the associated changes in surface morphology of the microspheres. In vivo experiments demonstrated that a single shot of hCG-loaded PLGA microspheres could produce a comparable antibody response with the inoculation of free hCG four times.

Purification, characterization, and cDNA sequence of halysetin, a disintegrin-like/cysteine-rich protein from the venom of Agkistrodon halys Pallas

By means of DEAE-Sepharose CL-6B column chromatography, gel filtration on Sephadex G-75 and Superose 12 FPLC, halysetin, an antiplatelet protein, was purified from the venom of Agkistrodon halys Pallas with molecular mass of 29 kDa on SDS-PAGE and 23,168 Da by mass spectrometry. The p1 was about 5.0. Halysetin was devoid of phospholipase A2, fibrino-(geno)lytic, esterase, hemorrhagenic activities. Halysetin dose-dependently inhibited the aggregation of human platelet, which was stimulated by collagen with IC50 of 420 nM, but not that stimulated by ADP. The N-and C-terminal sequences of halysetin were characterized. Its full-length cDNA was cloned by RT-PCR from the total RNA extracted from the snake venom gland. It encoded a protein of 212-amino-acid residues with disintegrin-like/cysteine-rich domains and was highly homologous with SYMPs (snake venom metalloprotease).

Cardiac swelling-induced chloride current is enhanced by endothelin

Endothelins (ETs) are a family of peptide hormones that act on G protein-coupled ET(A) and ET(B) receptors. ETs exert inotropic and chronotropic actions in the heart. Myocardial ischemia is associated with increased plasma levels of ET and cell swelling. We examined the effect of ETs on dog atrial swelling-induced chloride current (I(Cl,swell)). Whole-cell patch clamp was used; 10 nM ET-1 or ET-2 increased I(Cl,swell) by approximately twofold. ET-2 had no effect if I(Cl,swell) activation was prevented by hypertonic superfusate. Outward ET-2-induced current was blocked by 150 microM DIDS more effectively than inward current. Overnight pretreatment with phorbol 12-myristate 13-acetate (1.6 microM), pertussis toxin (100 ng/ml), or dialysis of the cell with 300 microM 2'-deoxyadenosine 3'-monophosphate, a P-site inhibitor of adenylyl cyclase, did not diminish the effect of ET-2. The effect of ET-2 was blocked by an ET(A1)- (BQ123), but not an ET(B)-selective (BQ788) antagonist. ET-2-induced currents were inhibited approximately 70% by PD 98059 (30 microM), a selective MAPK kinase (MEK) blocker. PD 98059 did not affect basal whole cell current or I(Cl,swell) before exposure to ET-2. The data suggest that MEK activity is not required for activation of atrial I(Cl,swell) but that ET-2 stimulates I(Cl,swell) by a MEK-dependent pathway.

Paucity of CFTR current but modest CFTR immunoreactivity in non-diseased human ventricle

We looked for evidence of expression of the cystic fibrosis transmembrane conductance regulator (CFTR) in non-diseased human ventricle. In rabbit and guinea pig the CFTR current is present in the highest density in subepicardial ventricular myocytes. In the present study, whole-cell patch-clamp was used to determine if a CFTR-like chloride current (I(CFTR,card)) can also be activated in human subepicardial ventricular myocytes. No evidence for I(CFTR,card) was detected in these electrophysiological studies when 10 microM forskolin was applied to 23 different cells from 4 donor hearts. Consistent with our previous results, a swelling-induced chloride current (I(Cl,swell)) could be observed after cell inflation. The enzymatic digestion of human ventricle to release single myocytes may have affected our ability to detect I(CFTR,card). Therefore, we looked for anti-CFTR immunoreactivity in slices of left ventricular free wall. A strong immunoreactivity signal was observed in guinea pig ventricle, a positive control. Background staining levels were seen in dog ventricle, a negative control tissue. Human anti-CFTR immunoreactivity was slightly above background. This low level of anti-CFTR immunoreactivity is consistent both with reports that CFTR mRNA is detectable in human ventricle and our inability to detect a significant I(CFTR,card) current density.

Isoprenaline can activate the acetylcholine-induced K+ current in canine atrial myocytes via Gs-derived betagamma subunits

1. G protein betagamma subunits activate the acetylcholine-induced potassium current IK,ACh. There is no evidence of specificity at the level of the betagamma subunits. Therefore all G protein-coupled receptors in atrial myocytes should be able to activate IK,ACh. Paradoxically, it is often stated that isoprenaline does not activate IK,ACh. Rationales to explain this negative result include insufficient concentrations of Gs in the atrium or restricted access of Gs-derived betagamma subunits to the IK,ACh channel. We took advantage of a non-specific increase in Gs that results after infection with adenovirus. 2. Adenoviral infection unmasked a 1 microM isoprenaline-induced IK,ACh which was prevented by propranolol. Isoprenaline occasionally activated IK,ACh in uninfected and freshly dissociated atrial myocytes but the effect was larger and more consistent in infected myocytes. 3. Pertussis toxin pretreatment (100 ng ml-1 overnight) did not block the effect of isoprenaline. The effect of isoprenaline became persistent if cells were pretreated with cholera toxin (200 ng nl-1). 4. Signal transduction events distal to adenylyl cyclase were not involved in isoprenaline-induced IK,ACh. Forskolin (10 microM) did not activate IK,ACh. Inhibition of adenylyl cyclase with cytoplasmic application of 300 microM 2'-deoxyadenosine 3'-monophosphate did not prevent the activation of IK,ACh by isoprenaline. 5. Cytoplasmic application of a betagamma binding peptide derived from the C terminus of beta-adrenergic receptor kinase 1 (50 microM) prevented the effect of isoprenaline on IK,ACh. The peptide did not prevent the stimulation of the L-type calcium current by isoprenaline. 6. The results indicate that beta-adrenoceptors can activate IK,ACh in atrial myocytes through the release of betagamma subunits from Gs.

Protein kinase C stimulates swelling-induced chloride current in canine atrial cells

The whole-cell patch-clamp technique was used to study the effect of protein kinase C (PKC) stimulation and alpha-adrenergic agonists on the swelling-induced chloride current (ICl,swell) in canine atrial cells. ICl,swell was activated by positive-pressure inflation. 4beta-Phorbol 12, 13-dibutyrate (PDBu) concentration-dependently stimulated ICl,swell. PDBu (500 nM) increased the current density of ICl,swell from 9.1+/-1.3 to 24.2+/-4.8 pA/pF at +20 mV (n=4). This effect developed slowly, reaching a steady-state after more than 5 min of exposure. 4alpha-Phorbol 12, 13-dibutyrate (4alpha-PDBu, 500 nM), an inactive analogue of PDBu, did not affect ICl,swell. The effect of PDBu was inhibited by bisindolylmaleimide I. After down regulation of PKC by phorbol 12-myristate 13-acetate (PMA, 1.6 microM, 24 h), ICl,swell no longer responded to PDBu (n=4). Neither the basal whole-cell current (prior to cell inflation) nor inflation-induced ICl,swell were affected by PKC down regulation. Phenylephrine did not affect ICl,swell. We conclude that PKC activity stimulates and does not prevent the activation of dog atrial ICl,swell. These results contrast with reports of PKC-dependent inhibition of rabbit atrial ICl,swell and currents conducted by ClC-3, a putative clone for ICl,swell. The data suggest species-dependent variations in the modulation of cardiac ICl,swell by PKC.

Delayed activation of cardiac swelling-induced chloride current after step changes in cell size

INTRODUCTION

A lag phase has been reported for the activation of cardiac swelling-induced chloride currents. Prior demonstrations of this lag used methods that produce gradual changes in cell size, making interpretation and quantification of the time course problematic.

METHODS AND RESULTS

Isolated dog atrial cells were studied using the whole cell, patch clamp technique. Step changes in cell size were produced by application of transient pulses of positive pressure, and the time course for activation of the swelling-induced chloride current was observed. There was a distinct temporal dissociation between size changes and current activation that was temperature sensitive. Activation half-times were 98 +/- 31 seconds and 586 +/- 112 seconds at 36 degrees C and room temperature, respectively. Swelling-induced chloride currents were evoked in a higher percentage of cells at 36 degrees C (83%) compared with room temperature (50%).

CONCLUSION

Cardiac swelling-induced chloride current activates with a distinct lag after step changes in cell size. The activation time course is temperature sensitive. These observations are consistent with the notion that signal transduction events, and not simply membrane stretch, are required for the activation of cardiac swelling-induced chloride current.

Purification, cDNA cloning and molecular characteristic of a fibrinolytic enzyme from the venom of Agkistrodon acutus

A nonglycoprotein-like fibrinolytic enzyme ((FIB-I) was purified from the crude venom of Agkistrodon acutus by CM-Sepharose CL-6B and DEAE-Sepharose CL-6B ion exchange chromatography and then by FPLC through Superose 12 gel filtration. Its molecular weight is about 23 kDa and isoelectric point is near 6.0. It not only has fibrinolytic and caseinolytic activity, but also can hydrolyze BAEE. The local hemorrhagic activity was found in mice after the subcutaneous injection of this enzyme. EDTA can inhibit its fibrinolytic activity completely, but PMSF and arrowhead proteinase inhibitor have no such obvious inhibitory effect, thus implying that FIB-I is a metalloproteinase. The N-terminal ten amino acid residues 'STEFQRYMEI' of FIB-I was elucidated. A full-length cDNA gene of this enzyme was cloned by using RT-PCR from the total RNA extracted from the snake venom gland and FIB-I was expressed in E. coli. Having analyzed the sequence, we found that it had a typical zinc-chelating characteristic as 'HEXXHXXGXXHD.'

ATP-dependent activation of the atrial acetylcholine-induced K+ channel does not require nucleoside diphosphate kinase activity

Prior reports by others have shown that cytoplasmically applied ATP can activate the acetylcholine-induced K+ channel in inside-out atrial membrane patches when no guanine nucleotides are present in the solution bathing the cytosolic face of the membrane. A nucleoside diphosphate kinase mechanism was proposed to explain the activation by ATP. We show in the present study that cytoplasmic adenylylimidodiphosphate mimics the activation by ATP. Unlike ATP, the activation by adenylylimidodiphosphate does not subside on washout. Although commercially available adenylylimidodiphosphate is contaminated by guanylylimidodiphosphate, the activation by adenylylimidodiphosphate still occurs after HPLC purification to remove guanine nucleotide contamination. Adenylylimidodiphosphate does not support phosphotransferase activity by nucleoside diphosphate kinase. Therefore, nucleoside diphosphate kinase activity cannot explain the activation of atrial acetylcholine-induced K+ current by ATP and adenylylimidodiphosphate. We hypothesize that the activation by millimolar concentrations of ATP is due to binding of adenine nucleotide to the guanine nucleotide binding site of the G protein(s) responsible for stimulating the acetylcholine-induced K+ current.

Modulation of dog atrial swelling-induced chloride current by cAMP: protein kinase A-dependent and -independent pathways

1. The modulation of dog atrial swelling-induced chloride current (I(Cl,swelling)) by cAMP-elevating agents was studied. Forskolin (10 microM) or isoprenaline (1 microM) exerted multiple effects. Although the pattern between cells was variable, there was, in general, a stimulatory action and a more slowly developing inhibitory effect. 2. In any given cell, the response to forskolin or isoprenaline was qualitatively similar suggesting that all of the responses were dependent on stimulation of adenylyl cyclase. The effects of forskolin or isoprenaline on I(Cl,swelling) were inhibited by intracellular dialysis with a P-site inhibitor of adenylyl cyclase, 2'-deoxyadenosine 3'-monophosphate (300 microM). 3. Intracellular dialysis with a peptide inhibitor of protein kinase A (PKI(6-22); 100 microM) blocked the inhibitory response to forskolin or isoprenaline and all cells responded with a monophasic stimulation of I(Cl,swelling). 4. After intracellular dialysis of cells with PKI(6-22) (100 microM) and cAMP (100 microM), current amplitude was not further stimulated by forskolin. 5. After intracellular dialysis with PKI(6-22) and adenosine 5'-O-(3-thiotriphosphate) (ATPgammaS), forskolin stimulated I(Cl,swelling) and the effect of forskolin subsided after it was washed out. 6. In conclusion, there are dual pathways by which cAMP can modulate dog atrial cell I(Cl,swelling). Inhibition results from protein kinase A (PKA)-dependent phosphorylation. In addition, a stimulatory pathway exists that is independent of phosphorylation by PKA or other cellular kinases. Although alternative explanations are possible, the stimulatory effect of cAMP may represent a direct modulation of I(Cl,swelling).

Cardiac swelling-induced chloride current depolarizes canine atrial myocytes

The effect of the cardiac swelling-induced chloride current (I(Cl,swell)) on the transmembrane potential was examined. Osmotic swelling affected the resting potassium current through an apparent dilution of intracellular potassium. Inflating cells by applying positive pressure to the patch electrode prevented the effect on the resting potassium current. Inflation depolarized dog atrial myocytes when the recording electrodes contained either 17 or 42 mM Cl-. The depolarization coincided with activation of I(Cl,swell) and was antagonized by the chloride-channel blocker niflumic acid. Substituting extracellular chloride with the more permeant ion SCN- shifted the reversal potential for I(Cl,swell) to more negative values and antagonized inflation-induced depolarization. The depolarization was accentuated by replacing extracellular chloride with a less permeant ion, aspartate. We conclude that activation of I(Cl,swell) in atrial cells causes significant depolarization of the resting membrane. The outward rectification of I(Cl,swell) and the high cell membrane resistance during the action potential plateau suggest that I(Cl,swell) will also have significant effects on atrial action potential configuration.

Carotid blood flow distribution, haemodynamics and inotropic responses following calcitonin gene-related peptide in the pig

The sensory neuropeptide, calcitonin gene-related peptide (alpha-CGRP), has been implicated in the pathogenesis of migraine headache. The present study aimed to evaluate the effects of intracarotid infusions of human alpha-CGRP (10, 30 and 100 pmol/kg.min; n = 8), as compared to that of saline (4 times; n = 8) on haemodynamics and blood flow distribution within the carotid circulation of the anaesthetized pig, using the radioactive microsphere method. Furthermore, the effects of antimigraine drugs, dihydroergotamine (100 micrograms/kg i.v.; n = 4) or sumatriptan (300 micrograms/kg i.v.; n = 4), on these parameters were studied in the presence of the infusion of the highest concentration of human alpha-CGRP. Additionally, putative positive inotropic responses to human alpha-CGRP (10(-9)-10(-7) M) were investigated in porcine isolated atrial and ventricular trabeculae. Human alpha-CGRP increased carotid artery blood flow and conductance dose-dependently, together with an enhancement in vascular pulsations. These effects were associated with a fall in systemic blood pressure with concomitant increases in heart rate and cardiac output. The increase in carotid blood flow was reflected by an increase in total capillary blood flow, predominantly to extracerebral tissues including the dura, whereas blood flow through arteriovenous anastomoses remained stable. Both dihydroergotamine and sumatriptan reduced carotid blood flow and its capillary fraction without affecting systemic vascular conductance. In tissues, these drugs reversed blood flow increases due to human alpha-CGRP in most extracerebral tissues, but failed to reduce dural blood flow. In porcine isolated atrial and ventricular trabeculae, noradrenaline (10(-8)-10(-5) M) increased force of contraction in a concentration-dependent manner. In contrast, human alpha-CGRP (10(-9)-10(-7) M) failed to increase force of contraction in atrial trabeculae (n = 6) and exerted only a moderate concentration-dependent positive inotropic effect in ventricular trabeculae (approximately 25% of the response to 10(-5) M noradrenaline, n = 10). These data indicate that human alpha-CGRP caused arteriolar dilatation together with a fall in blood pressure in the pig. The tachycardia may be reflex-mediated, but the peptide also exerts a moderate positive inotropic action on ventricular trabeculae. The fall in systemic arterial blood pressure and the marked increase in capillary blood flow most likely prevented the opening of arteriovenous anastomoses. Furthermore, the antimigraine drugs, dihydroergotamine and sumatriptan, were able to reverse blood flow changes induced by human alpha-CGRP in the porcine carotid circulation.

Characterization of the positive and negative inotropic effects of acetylcholine in the human myocardium

In the human isolated myocardium, acetylcholine (10(-9) to 10(-3) M) elicited a biphasic inotropic effect (a decrease in the lower and an increase in the higher concentration range) in atrial and a positive inotropic effect in ventricular trabeculae. However, under conditions of raised contractility achieved by exposure to noradrenaline (10(-5) M), only negative inotropic effects were observed in both atria and ventricles. Atropine (10(-6) M), but not propranolol (10(-6) M), antagonized both positive and negative inotropic effects of acetylcholine, thus showing that the responses were mediated by muscarinic acetylcholine receptors. The use of subtype selective muscarinic receptor antagonists (10(-7) to 10(-5) M), pirenzepine (M1 > M3 > M2), AF-DX 116 (11-([2-[(diethylamino)-methyl]-1-piperidyl]acetyl)-5,11-dihydro-6H- pyridol[2,3-b][1,4]benzodiazepine-6-one base; M2 > M1 > M3) and HHSiD (p-fluorohexahydro-siladifenidol hydrochloride; M3 > or = M1 >> M2) revealed that the negative inotropic effect of acetylcholine in atrial as well as the positive inotropic effect in ventricular trabeculae were best antagonized by AF-DX 116 and not by pirenzepine, suggesting the involvement of the muscarinic M2 receptor subtype, possibly linked to different second messenger systems. On the other hand, the positive inotropic effect of acetylcholine (10(-6) to 10(-3) M) in the atrial tissue, observed only in preparation with depressed contractility, was not effectively antagonized by either AF-DX 116 or HHSiD, but was significantly reduced by pirenzepine. (ABSTRACT TRUNCATED AT 250 WORDS)

Different pharmacological responses of atrium and ventricle: studies with human cardiac tissue

It has been recently reported that 5-hydroxytryptamine (5-HT) increases force of contraction in atrial tissue but not in ventricular tissue. In the present study with trabeculae obtained from non-diseased human hearts, we investigated whether this difference in the contractile responses is specific for 5-HT or is also observed for other substances: calcitonin gene-related peptide (CGRP), angiotensin II, adenosine, somatostatin and acetylcholine. CGRP (10(-9) to 10(-7) M) and angiotensin II (10(-9) to 10(-5) M) caused concentration-dependent increases in force of contraction in atrial trabeculae (up to 36 +/- 8% and 42 +/- 8% of the response to 10(-5) M noradrenaline, respectively). Similar to 5-HT, no effects were observed with CGRP and angiotensin II in ventricular trabeculae. Adenosine (10(-8) to 10(-5) M) and somatostatin (10(-8) to 10(-6) M) caused concentration-dependent negative inotropic effects on baseline atrial contractility (-54 +/- 17% and -51 +/- 25%, respectively), but no response was found on baseline ventricular contractility. Adenosine, but not somatostatin, reduced force of contraction after pre-stimulation with 10(-5) M noradrenaline in atrial tissue and, to a lesser extent, in ventricular tissue. Acetylcholine exhibited a biphasic concentration-response curve in the atrial tissue, consisting of an initial negative inotropic response (10(-9) to 10(-7) M, from 120 +/- 41 mg at baseline to 48 +/- 16 mg at 10(-7) M), followed by a positive inotropic response (10(-6) to 10(-3) M, from 48 +/- 16 mg at 10(-7) M to 77 +/- 15 mg).(ABSTRACT TRUNCATED AT 250 WORDS)