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Objective: To investigate knee contact forces (KCFs), and their relationships with knee pain, across grades of radiographic knee osteoarthritis (OA) severity.Design: Cross-sectional exploratory analysis of 164 participants with medial knee OA. Radiographic severity was classified as mild (grade 2), moderate (grade 3) or severe (grade 4) using the Kellgren & Lawrence (KL) scale. Walking knee pain was assessed using an 11-point numerical rating scale. External knee adduction moment (external KAM) and internal muscle forces were used to calculate medial, lateral and total KCFs using a musculoskeletal computational model. Force-time series across stance phase of gait were compared across KL grades using Statistical Parametric Mapping. Associations between KCFs and pain across KL grades were assessed using linear models.Results: Medial KCFs during early and middle stance were higher in participants with KL3 and KL4 compared to those with KL2. In contrast, lateral KCFs were higher in those with KL2 compared to KL3 and KL4 in middle to late stance. The external loading component (i.e., KAM) of the medial KCF during middle to late stance was also greater in participants with KL3 and KL4 compared to those with KL2, whereas the internal (i.e., muscle) component was greater in those with KL3 and KL4 compared to KL3 during early stance. There were no associations between medial KCF and knee pain in any KL grade.Conclusions: Medial and lateral KCFs differ between mild, moderate and severe radiographic knee OA but are not associated with knee pain severity for any radiographic OA grade. [ABSTRACT FROM AUTHOR]

The deep circumflex iliac artery perforator flap with iliac crest (DCIAPF) is considered a favourable single-flap option for oromandibular reconstruction. The aim of this study was to evaluate the effectiveness of venous superdrainage using the superficial circumflex iliac vein (SCIV) in the DCIAPF for oromandibular reconstruction. The data of 22 patients (12 female, 10 male) aged 10–76 years (median 53 years) who underwent simultaneous oromandibular reconstruction with a DCIAPF were reviewed retrospectively. Eleven patients received the DCIAPF with SCIV for superdrainage (group A) and another 11 patients received the conventional single-pedicled DCIAPF flap (group B). No flap loss occurred in either group. Venous congestion due to relative venous insufficiency was significantly more frequent in group B (P = 0.045). There was no significant difference in the incidence of partial flap necrosis and wound dehiscence, or in the total operation time between the two groups. Superdrainage using the SCIV has the potential to reduce the incidence of venous congestion due to relative venous insufficiency in DCIAPF used for oromandibular reconstruction. [ABSTRACT FROM AUTHOR]

Hepatoblastoma is the most common type of liver cancer in children. Refined therapeutic approaches combining risk-adapted chemotherapy along with complete tumor resection has led to improved survival. We aimed to evaluate the current state of management and outcomes for hepatoblastoma in the United States. We retrospectively reviewed 794 children (<18 years) with hepatoblastoma from the National Cancer Database (2004–2015). We assessed overall survival by means of Kaplan-Meier method, log-rank tests, and multivariable Cox regression. Median age was 1 year (interquartile range: 0–2) and 170 (21.4%) presented with metastatic disease. Surgical resection was included in the treatment of 614 (77.3%) children (resection in 66.8% and liver transplantation in 10.6%). In the entire cohort, 95.1% of children received chemotherapy. In the surgical cohort, 575 (93.6%) received chemotherapy (34.5% neoadjuvant, 28.7% adjuvant, 30.5% both neoadjuvant and adjuvant). The 5-year overall survival was 76.6% for the entire cohort (no-surgery group: 55.3% vs surgery group: 82.8%). In multivariable analysis for all children, age ≥8 years (P =.009), metastasis (P <.001), surgery only (P =.009), and chemotherapy only (P <.001) were risk factors for mortality. In multivariable analysis for the surgical cohort, metastasis (P =.001), multifocality (P =.02), no chemotherapy (P =.03), and margin-positive resection (P =.02) were risk factors for mortality. Excellent long-term overall survival is achievable with a combination of chemotherapy and surgical resection when a negative resection margin is achieved. However, nearly a quarter of children never received surgical treatment, representing a potential opportunity for improvement in care. [Display omitted] [ABSTRACT FROM AUTHOR]

Adamantinoma is an extremely rare tumour originating from bone that can be divided into classical and osteofibrous dysplasia (OFD)-like adamantinoma. This low-grade malignancy almost exclusively occurs in long bones, and only few cases of mandibular adamantinoma have been reported. Here, we report the case of a 30-year-old female with a 2-year history of right mandible tenderness. Radiological examinations showed a lytic lesion involving the right mandible without a well-defined margin. Biopsy confirmed the diagnosis of adamantinoma. She underwent a segmental mandibulectomy and reconstruction with a fibula flap. The definitive diagnosis was OFD-like adamantinoma. However, the tumour recurred after 5 years. The residual mandible and fibula flap were widely involved. A total mandibulectomy was performed. Five years later, there is no evidence of recurrence or metastasis. We recommend that adamantinoma be treated by radical resection with clear margins, and long-term surveillance is necessary due to the likely high local recurrence rate and the potential for late tumour metastasis. [ABSTRACT FROM AUTHOR]

Background: Globally, there have been many cases of coronavirus disease 2019 (COVID-19) among medical staff; however, the main factors associated with the infection are not well understood.Aim: To identify the super-factors causing COVID-19 infection in medical staff in China.Methods: A cross-sectional study was conducted between January 1st and February 30th, 2020, in which front-line members of medical staff who took part in the care and treatment of patients with COVID-19 were enrolled. Epidemiological and demographic data between infected and uninfected groups were collected and compared. Social network analysis (SNA) was used to establish socio-metric social links between influencing factors.Findings: A total of 92 medical staff were enrolled. In all participant groups, the super-factor identified by the network was wearing a medical protective mask or surgical mask correctly (degree: 572; closeness: 25; betweenness centrality: 3.23). Touching the cheek, nose, and mouth while working was the super-factor in the infected group. This was the biggest node in the network and had the strongest influence (degree: 370; closeness: 29; betweenness centrality: 0.37). Self-protection score was the super-factor in the uninfected group but was the isolated factor in the infected group (degree: 201; closeness: 28; betweenness centrality: 5.64). For family members, the exposure history to Huanan Seafood Wholesale Market and the contact history to wild animals were two isolated nodes.Conclusion: High self-protection score was the main factor that prevented medical staff from contracting COVID-19 infection. The main factor contributing to COVID-19 infections among medical staff was touching the cheek, nose, and mouth while working. [ABSTRACT FROM AUTHOR]

Objectives: This study:Healthy Active and in Control (HA1C), examined the feasibility and acceptability of yoga as a complementary therapy for adults with Type-2 Diabetes (T2DM).Design: A 2-arm randomized clinical trial comparing Iyengar yoga with a supervised walking program.Setting: Hospital based gym-type facility and conference rooms.Interventions: Participants were randomized to a 12-week program of either; (1) a twice weekly Iyengar yoga, or (2) a twice-weekly program of standard exercise (SE).Main Outcome Measures: Primary outcomes assessed feasibility and acceptability, including enrollment rates, attendance, study completion, and participant satisfaction. Secondary outcomes included HbA1c, physical activity, and measures of diabetes-related emotional distress, self-care and quality of life (QOL). Assessments were conducted at baseline, end of treatment, 6-months and 9-months post-enrollment.Results: Of 175 adults screened for eligibility, 48 (30 women, 18 men) were eligible and enrolled. The most common reasons for ineligibility were orthopedic restrictions, HbA1c levels <6.5 and BMI > 42. Session attendance was high (82% of sessions attended), as was follow-up completion rates (92%). Program satisfaction rated on a 5-point scale, was high among both Yoga (M = 4.63, SD = 0.57) and SE (M = 4.77, SD = 0.52) participants. Overall 44 adverse events (26 Yoga, 18 SE) were reported. Of these, six were deemed "possibly related" (e.g., neck strain, back pain), and 1 "probably related" (ankle pain after treadmill) to the study. Yoga produced significant reductions in HbA1c. Median HbA1c at 6 months was 1.25 units lower for Yoga compared to SE (95% CI: -2.54 -0.04). Greater improvements in diabetes self-care, quality of life, and emotional distress were seen among Yoga participants than among SE participants. Increases in mindfulness were seen in Yoga but not in SE.Conclusions: The yoga intervention was highly feasible and acceptable, and produced improvements in blood glucose and psychosocial measures of diabetes management. [ABSTRACT FROM AUTHOR]

This study aimed to analyze the changes in mandibular morphology after bilateral mandibular distraction osteogenesis (BMDO) in children with Pierre Robin sequence. The positions of the condyles were analyzed in reconstructed three-dimensional craniomaxillofacial images obtained for 18 children before and 8–12 weeks after BMDO. Differences between pre- and postoperative parameters were assessed using paired t -tests. After surgery, a significant decrease in superior joint space was detected ( P < 0.05), but no change in anterior joint space or posterior joint space was observed. The ratio of the distance between gonia and distance between condylion points (GoL–GoR/CoL–CoR) ( P < 0.001) and the distances between the condyle and midsagittal plane ( P < 0.001) increased after surgery, while the condylar horizontal angle decreased ( P < 0.05). No change in condylar vertical angle was noted. After BMDO, the condyle displayed an outward and upward shift, as well as outward rotation along the proximal segment. The mandible body exhibited forward movement with a more significant opening range. These changes were consistent with the extent of the newly formed bone tissue and the improvement in coordination and appearance of the children’s facial structures. The long-term effects of changes in condylar position on the development of the maxillofacial structures needs to be studied further. [ABSTRACT FROM AUTHOR]

This study was performed to investigate the incidence of and risk factors for postoperative cleft relapse and oronasal fistula after Furlow palatoplasty in infants. Sixty-two infants with cleft palate, aged 6–12 months (mean 8.25 months), who underwent cleft repair by Furlow double opposing Z-plasty between March 2012 and August 2014, were enrolled in the study. Risk factors for postoperative cleft relapse and oronasal fistula after Furlow palatoplasty were identified by logistic regression analysis. The incidence rates of cleft relapse at 1 week and oronasal fistula at 3 months after surgery were 24.2% (15/62) and 9.7% (6/62), respectively. Among all of the variables screened, only the width of the cleft was significantly associated with the incidence of postoperative cleft relapse ( P = 0.001) and oronasal fistula ( P = 0.011); the incidence rates were positively correlated with the width of the cleft when it exceeded 6.8 mm and 7.5 mm, respectively. Based on these findings, in order to reduce the incidence of postoperative cleft relapse and oronasal fistula, Furlow repair is not recommended for patients with wide clefts. An appropriate angle between the Z-flap incision and the central axis, use of a bilateral relaxation incision, and postoperative nursing care can help reduce the incidence of postoperative cleft relapse. [ABSTRACT FROM AUTHOR]

The lingual lymph nodes (LLNs) can only be detected with difficulty in early-stage tongue squamous cell carcinomas owing to the small size. Recurrence or metastasis could occur in the floor of the mouth as a result of neglecting the LLNs. The injection of carbon nanoparticles to track occult LLNs in early-stage tongue squamous cell carcinoma is presented and discussed. This technique is simple and easy to use intraoperatively. If LLNs were stained black during the operation, the sublingual gland along with the fatty tissue of the floor of the mouth were removed simultaneously. The LLNs in early-stage tongue squamous cell carcinoma deserve more attention. [ABSTRACT FROM AUTHOR]

Introduction: A triage cardiology program, in which cardiologists provide consultation to the Emergency Department (ED), may safely reduce admissions. For patients with chest pain, the HEART Pathway may obviate the need for cardiology involvement, unless there is a difference between ED and cardiology assessments. Therefore, in a cohort concurrently evaluated by both specialties, we analyzed discordance between ED and cardiology HEART scores.Methods: We performed a single-center, cross-sectional, retrospective study of adults presenting to the ED with chest pain who had a documented bedside evaluation by a triage cardiologist. Separate ED and cardiology HEART scores were computed based on documentation by the respective physicians. Discrepancies in HEART score between ED physicians and cardiologists were quantified using Cohen κ coefficient.Results: Thirty-three patients underwent concurrent ED physician and cardiologist evaluation. Twenty-three patients (70%) had discordant HEART scores (κ = 0.13; 95% confidence interval, -0.02 to 0.32). Discrepancies in the description of patients' chest pain were the most common source of discordance and were present in more than 50% of cases. HEART scores calculated by ED physicians tended to overestimate the scores calculated by cardiologists. When categorized into low-risk or high-risk by the HEART Pathway, more than 25% of patients were classified as high risk by the ED physician, but low risk by the cardiologist.Conclusion: There is substantial discordance in HEART scores between ED physicians and cardiologists. A triage cardiology system may help refine risk stratification of patients presenting to the ED with chest pain, even when the HEART Pathway tool is used. [ABSTRACT FROM AUTHOR]

Introduction Intraductal papillary mucinous neoplasm (IPMN) is a field defect disease of pancreas that has malignant potential. Many studies have recommended surgery as the preferred treatment. We investigated whether a total pancreatectomy (TP) can improve patient prognosis compared to a pancreatoduodenectomy (PD) and the indications for each approach. Patients and methods We obtained data of 548 malignant IPMN patients who underwent either a TP or a PD from SEER database. The survival rates were analyzed using the Kaplan–Meier method and a Cox regression model. Cases were subdivided to investigate the advantages of each procedure. Results The surgical procedures (PD and TP) did not significantly affect either cancer-specific survival (CSS) times or overall survival (OS) times in both Kaplan–Meier analysis and Cox regression (Kaplan–Meier: P CSS = 0.919, P OS = 0.996; Cox: P CSS = 0.735, P OS = 0.820). In the subgroup analyses, patients in stage T4 and AJCC stage III in the TP group had a longer survival time than did those in the PD group (33 months vs 14 months), but not significant (T4: P CSS = 0.124, AJCC III: P CSS = 0.102). In addition, PD had the trend to be better for poorly differentiated patients (P os = 0.055) and older patients. Conclusion TP did not offer any significant OS and CSS benefits as compared to PD. However, for patients in stage T4 and AJCC stage III, TP may extend survival time in some degree. In older or histologically poorly differentiated patients, PD may be preferable to TP. The results are rational, but still warrant further verification due to limited sample volumes of specific subgroups. [ABSTRACT FROM AUTHOR]

Defects of pressure piping, especially cracks, are inevitable during the lifetime of pipe, which will result in the pipe failure. In order to ensure safe operation of pipe, failure assessment for the pressure pipe containing defects needs to be implemented. In fact, the assessment parameters would show two types of uncertainty: randomness and fuzziness, because of the errors of inspection and lack of precise information. In this paper, a fuzzy-probabilistic failure assessment method has been developed based on Failure Assessment Diagram (FAD) from API 579-1/ASME FFS-1 procedure. This method combines the probability theory with possibility theory to deal with fuzzy and random variables. Also, Monte Carlo simulation is used to calculate the failure probability of pipe. This method was applied to a pipe with a surface crack. The effects of variables and their uncertainties on failure probability were analyzed. The results show that the wall thickness and diameter of the pipe has the most important contribution to the pipe failure, followed by the fracture toughness, the yield strength, the operating pressure, the depth and length of the crack. [ABSTRACT FROM AUTHOR]

Objective: The objective of the study is to compare the risks and benefits of lumbar puncture (LP) to evaluate for subarachnoid hemorrhage (SAH) after a normal head computed tomographic (CT) scan.Methods: This was an observational study of adult emergency department patients at a single hospital who presented with headache and underwent LP after a normal head CT to evaluate for SAH. Lumbar puncture results classified as indicating a SAH included xanthochromia in cerebrospinal fluid (CSF) or red blood cells in the final tube of CSF with an aneurysm or arteriovenous malformation on cerebral angiography. An LP-related complication was defined as hospitalization or a return visit due to symptoms attributed to the LP. Proportions of the study patients who had SAH diagnosed by LP and who experienced an LP-related complication were compared.Results: The study included 302 patients, including 2 (0.66%) who were diagnosed with SAH based on LP (number needed to diagnose, 151); both of these patients had a known intracranial aneurysm. Eighteen (5.96%) patients experienced an LP-related complication (P < .01 compared with number with SAH diagnosed; number needed to harm, 17). Complications included 12 patients with low-pressure headaches, 4 with pain at the LP site, and 2 with contaminated CSF cultures.Conclusion: The yield of LP for diagnosing SAH in adults with nontraumatic headache after a normal head CT was very low. The severity of LP-related complications was low, but complications were more common than SAH diagnoses. Lumbar puncture may not be advisable after a normal head CT to evaluate for SAH, particularly in patients with low-risk clinical features for SAH. [ABSTRACT FROM AUTHOR]

Introduction Intrahepatic cholestasis of pregnancy (ICP) is a pregnancy-specific disorder, which is characterized by raised serum bile acid level and potential adverse fetal outcome. Farnesoid X receptor (FXR), also known as a bile acid receptor, was found to be expressed in placenta with low level. Whether activation of FXR by specific agonists could regulate the pathogenesis of ICP is still unclear. Methods A model of maternal cholestasis was induced by administration of 17α-ethynylestradiol (E2) in pregnant mice for 6 days. We explored the regulatory effect of WAY-362450 (W450), a highly selective and potent FXR agonist on placenta. Results In this study, we demonstrated that administration of E2 increased bile acid levels in mouse serum, liver and amniotic fluid. Bile acid levels were significantly decreased after W450 treatment. W450 protected against the impairment of placentas induced by E2, including severe intracellular edema and apoptosis of trophoblasts. Moreover, W450 significantly induced the expressions of FXR target bile acid transport gene ATP-binding cassette, sub-family B (MDR/TAP), member 11 ( Abcb11 ; Bsep ) in placenta. W450 could also attenuate placental oxidative stress and increase the expressions of antioxidant enzymes Prdx1 and Prdx3 . Discussion and conclusion In conclusion, our data demonstrated that FXR agonist W450 modulated bile acid balance and protected against placental oxidative stress. Thus, our results support that potent FXR agonists might represent promising drugs for the treatment of ICP. [ABSTRACT FROM AUTHOR]

In the research, fractal theory was adopted in water supply network. K-means algorithm was adopted to make the nodes multistage cluster zoning, and prioritize nodes was determined according to the actual situation of each zone level division. In each zone, prim algorithm completed each sub-region of water supply pipe network based on the use of fractal growth of self-organization. The established water supply network could be operated and managed according to the form of partition. The fractal self-growth model was applied to the water distribution system planning of one north city in China, the results clearly show the economic effectiveness. [ABSTRACT FROM AUTHOR]

The paper investigates an optimized leakage locating model combining Genetic Algorithms and Bayesian Decision Theory in water distribution networks. Both of the leakage detection models based on model calibration and Bayesian Decision Theory are described in the paper and contribute to the establishment of the optimized model. A numerical example network was used for evaluation of the optimized model and proves its excellent detection accuracy and outstanding locating efficiency. [ABSTRACT FROM AUTHOR]

Introduction Gestational trophoblastic disease (GTD) is a heterogeneous group of pregnancy-related disorders. Hydatidiform mole (HM) is the most common type of GTD, whereas gestational choriocarcinoma is the most aggressive. Non-receptor tyrosine kinase c-Src contributes to the transformation to a malignant phenotype in various cancers. However, the role of c-Src in the pathogenesis of GTD remains largely unknown. Methods The expression level of phosphorylated c-Src was determined by immunohistochemistry and Western blotting assay. JAR and JEG-3 cells were treated with hCG, specific c-Src inhibitor saracatinib and PP2, and PKA specific inhibitor, PKI. Cell growth rate and cell migration/invasion ability was determined by cell proliferation and transwell assays respectively. Results c-Src was highly activated in HM tissues and choriocarcinoma cells (JAR and JEG-3). c-Src was activated by hCG in a time and concentration-dependent manner, which was abrogated by specific c-Src and PKA inhibitors. Inhibition of c-Src activity in JAR and JEG-3 cells by saracatinib leaded to a decrease in the rate of cell growth and cell migration/invasion ability. Furthermore, inhibition of c-Src phosphorylation induced cell cycle arrest and reduced expressions of cyclin A2, cyclin B1, cyclin E1, FOXD3 and NANOG. Moreover, inhibition of c-Src activity resulted in decreased p-FAK Tyr397 phosphorylation. Discussion and conclusion Our findings indicate an important role of c-Src in the pathogenesis of GTD, and we propose that c-Src inhibitors are potential adjuvant chemotherapeutic drugs for the treatment of GTD. [ABSTRACT FROM AUTHOR]

Abstract: As a proof of concept a Centrifugal Particle Receiver (CentRec) prototype in laboratory scale (∼10 kWth) was designed, built and tested in the High-Flux Solar Simulator in Cologne, Germany. Since they can be heated up to 1000°C without sintering in the storage, small bauxite particles produced for the oil and gas industry are used as the absorber, the heat transfer and storage media at the same time. A defined rotation is used to form a thin direct absorbing particle film on the inner surface of the cylindrical receiver. Depending on the incoming heat flux the particle residence time can be adjusted by controlling rotation speed and mass flow. A constant particle outlet temperature for all load conditions can be therefore ensured. First experiments were conducted with various power levels and mass flows at two different receiver inclinations. Particle outlet temperatures of up to 900°C were demonstrated and the expected simple control capability of the receiver concept was verified. [Copyright &y& Elsevier]

Abstract: Due to various influence, some potential risks were hidden in water supply system. In order to control unexpected accidents, the fuzzy comprehensive evaluation method for risk assessment is adopted in this paper. The most serious risk internal cause of water supply system is water hammer, and to eliminate the potential risks of pipe burst, water hammer was calculated under various conditions, to identify pipeline weak sections. The submerged model of was established. According to the simulation of typical case, the plan of emergency was made to deal with a series of problems caused by pipeline rupture. [Copyright &y& Elsevier]

Abstract: In this paper, we introduce smart sensors for monitoring water distribution systems. To improve the quality of monitoring and prolong the lifetime of the sensor node, there is a need to reduce the amount of data transmitted by predicting the future behaviour of the data while detecting and classifying important events locally in the sensor node, transferring only important data. We propose to reduce the amount of data transmitted between the sensor node and end user by using Principle Component Analysis (PCA) and dual prediction models for the monitoring of hydraulic data based on an Autoregressive Moving Average (ARMA) model. [Copyright &y& Elsevier]

Abstract: In consideration of using fewer decision variables in building least cost pumping operation optimal, the two-phase optimal method is used as the frame. By abstracting pump stations into high level reservoirs, the water distribution system hydraulic model can be modified into a modality, which can be used in first optimal phase of two-phase optimal method. And by building on feasible pump combination database, a new optimal method in the second optimal phase will be proposed. And the proposed new method in the second optimal phase will be embedded into the first optimal phase, so that the problem of results discordant in different phases of two-phase optimal method will be solved. By introducing new concept and improving present optimal method, a more practical optimal operation method of water distribution system (WDS) will be established. By applying to a large scale water distribution system, the practicability of proposed method has been evaluated. [Copyright &y& Elsevier]

Abstract: The main aim of optimal schedule of traditional water distribution system is to reduce energy consumption, without consideration of minimizing network leakage. This research is on the premise of meeting water demand, pressure and quality, at same time taking the minimization of network leakage and power consumption as the optimization objectives, taking pump and valve opening and closing as decision variables, to build leakage control model of multi-source water distribution system by optimal pump schedule. On the basis of this model, the partition scheme and pump scheduling of water supply system are determined; the NSGA-II algorithm is used for solving the optimisation problem. By applying it to practical water supply network in HD city, the results showed thatthis method can simultaneously reduce power consumption and network leakage. [Copyright &y& Elsevier]

Abstract: Aims: We investigated the relationship between predominant subtype, according to the International Association for the Study of Lung Cancer/American Thoracic Society/European Respiratory Society International Multidisciplinary Lung Adenocarcinoma Classification, and prognosis in stage I lung adenocarcinoma in Zhejiang Cancer Hospital. Methods: Two hundred and sixty-one patients with stage I lung adenocarcinoma, operated in Zhejiang Cancer Hospital, were identified between 2000 and 2010. Survival curves were plotted using the Kaplan–Meier method. The Cox proportional hazard model was used for multivariate analysis. Results: None of the cases were adenocarcinoma in situ and six were minimally invasive adenocarcinomas. Two hundred and fifty-five cases were invasive adenocarcinoma. Of those, 80, 76, 42, 34, 19, and 4 were papillary predominant, acinar predominant, micropapillary predominant, solid predominant, lepidic predominant subtypes, and variants of invasive adenocarcinoma, respectively. Patients with micropapillary and solid predominant tumors had a significantly worse disease-free survival as compared to those with other subtypes predominant tumors (p < 0.001). Multivariate analysis revealed that the new classification was an independent predictor of the disease-free and overall survival (p = 0.002 and 0.015). Conclusion: The predominant subtype in the primary tumor was associated with prognosis in resected stage I lung adenocarcinoma. [Copyright &y& Elsevier]

Abstract: In oromaxillofacial surgery patients, the incidence of difficult airways is up to 15.4–16.9%. Blind nasal intubation remains a safe technique for difficult airway management in some remote areas where a fibreoptic bronchoscope is not always available. The lightwand is an easy-to-use, highly economical device, and can facilitate endotracheal intubation through illumination in the neck. The study aims to evaluate the efficacy of nasotracheal intubation using lightwand in oromaxillofacial surgery patients with difficult airways. One hundred and sixteen patients with difficult airways requiring nasotracheal intubation were randomly divided into a lightwand group and a blind group, with 58 cases in each group. The first attempt and overall success rates of lightwand intubation were 84.5% and 93.1%, respectively, which were higher than those of blind intubation (65.5% and 75.9%, respectively; P <0.05). The total intubation time was 91.4±27.7s in the lightwand group and 130.7±33.4s in the blind group (P <0.001). Patients in the lightwand group also experienced more stable haemodynamic responses and less pharyngalgia. In conclusion, lightwand-guided nasotracheal intubation is superior to blind intubation in patients with difficult airways, with a higher success rate, more stable haemodynamic responses, and fewer postoperative complications. [Copyright &y& Elsevier]

Abstract: The FAIR project undertaken at GSI (Darmstadt, Germany) will lead to the construction of 2 superconducting synchrotrons and one superconducting fragment separator called Super-FRS. This paper presents quench measurements and calculations on the FAIR Super-FRS dipole using two different 3D FEM programs. The first (called Opera Quench) gives the same order of propagation velocities as those computed with a 1D program. The second (developed by CIEMAT) succeeds to reproduce the current drop and quench resistance measured on the Super-FRS dipole. [Copyright &y& Elsevier]

Abstract: This paper attempts to develop a simple and practical procedure for the optimal design of machine tool bed. In this research, a simplified model is first defined to characterize the bed structure. The load bearing topology of the bed structure is then identified to represent the optimal layout of the inner stiffener plates. Subsequently, detailed sizing optimization is conducted by using a novel criterion which describes the best solution in terms of weight distribution of both the outer supporting panels and inner stiffener plates. Finally, calculation results are elaborated to demonstrate the effectiveness of the proposed method. [Copyright &y& Elsevier]

Abstract: Spatiotemporal variation analysis of water quality and identification of water pollution sources in river basins is very important for water resources protection and sustainable utilization. In this study, fuzzy comprehensive analysis and two statistical methods including cluster analysis and seasonal Kendall test method were used to evaluate the spatiotemporal variation of water quality in the Zhangweinan River basin. The results for spatial cluster analysis and assessment on water quality at 19 monitoring sites indicated that water quality in the Zhangweinan River basin could be classified into two regions according to pollution levels. One is the Zhang River basin located in northwest of the Zhangweinan River basin where water quality is good. Another one includes the Wei River and eastern plain of the Zhangweinan River basin, and the water pollution in this region is serious, where the pollutants from point sources flow into the river and the water quality changes greatly. The results of temporal cluster analysis and seasonal Kendall test indicated that the sampling periods may be classified into three periods during 2002-2009 according to water quality. Results of temporal cluster analysis and seasonal Kendall test indicated that the study periods may be classified into three periods and two different trends was detected during the period of 2002-2009. The first period was the year of 2002-2003, during which water quality had deteriorated and serious pollution was observed in the Wei River basin and eastern plain of the Zhangweinan River basin. The second period was the year of 2004-2006, during which water quality became better. The year of 2007-2009 is the third period, during which water quality had been improved greatly. Despite that water quality in the Zhangweinan River basin had been improved during the period of 2004-2009, water quality in the Wei River (southwestern part of the basin), the Wei Canal River and the Zhangweixin River (eastern plain of the basin) is still poor. These results provide may useful information for better pollution control strategies in the Zhangweinan River basin. [Copyright &y& Elsevier]

Abstract: Baojixia water diversion works have direct impacts on river hydrology, primarily resulting in the changes of the magnitude, frequency of low and high flows, ultimately generating a new hydrologic regime differing significantly from the natural flow regime. Streamflow and precipitation data from 1944 to 2008 at Linjiacun station are analyzed in this study. In order to evaluate hydrologic alteration before and after water diversion, the Range of Variability Approach (RVA) is used in this paper, and hydrologic data was divided into two periods: before and after 1972, when Baojixia diversion works brought to service in the Wei River. It is supposed that the hydrologic time series before 1972 represents the hydrologic regime for the pre-impact period, and that after 1972 for the post-impact period. The Chi-square test is used to analyze the hydrologic alteration of monthly flows, which is classified as low, middle and high hydrologic alterations. Flow Duration Curve (FDC) representing the relationship between the magnitude and frequency of streamflow was used to investigate flow characteristics from low flow to high flow. FDC is categorized as three parts on the basis of magnitude of streamflow: high flow (below 10% of exceedance frequency), low flow (over 90% of exceedance frequency) and constant flow (from 10% to 90% of exceedance frequency). The results show that the magnitude of monthly flow decreased obviously in the post-impact period, especially in dry seasons. The degree of hydrologic alteration is high. The shape of FDC in the post-impact period is different from that in the pre-impact period. There is an obvious trend for FDC in the pre-impact period, while there is no obvious regularity between magnitude of streamflow and exceedance probability in the post-impact period. According to the analysis on the data of water diversion, water withdrawn accounted for about 80 percent of natural runoff in dry seasons. This may be the reason why the alteration of monthly flow in dry seasons is highest. In summary, monthly streamflow after 1972 changed greatly because of water diversion. This analysis makes one to understand hydrologic regime well, and will be helpful for the management of water resources in the Wei River basin. [Copyright &y& Elsevier]

Abstract: An ecological base flow method is developed to estimate the ecological base flows of Wei River in Shaaxi province. The method considers not only the self purification flow to fulfill the water quality demand, but also the flow demand for the existing aquatic lives’ habitat. A water quality model is developed to estimate the self purification flow for four scenarios, including the present emission and other 3 scenarios corresponding to different measurements of pollution treatment. The flow demand of the existing aquatic lives’ habitat is calculated by the biological indicator method. By synthesizing these flow demands, the ecological flow of Wei River in Shaanxi province is estimated. The results are also compared with those of other methods, such as the Tennant method, the wetted perimeter method, and the R2ROSS method. It shows that the proposed method has more reliability and is more suitable for the calculation of the ecological base flow of Wei River in Shaanxi province. [Copyright &y& Elsevier]

Abstract: The dynamics of nickel (Ni) uptake, transfer, retention and clearance in fetuses and late gestational rats were investigated by assessing its distributions in placenta, maternal and fetal organs and tissues during the 24 h period after a single dose of 63Ni intraperitoneal injection on gestational day 20. Peak 63Ni radioactivity was detected at 0.5 h in maternal blood, at 3 h in placenta, fetal membranes, fetal blood, fetal heart, maternal kidney, lung, stomach, liver and brain, at 9 h in fetal kidney, stomach, liver and brain, and lastly at 24 h in fetal lung and amniotic fluid. The maximal 63Ni radioactivity among all samples was detected consistently in the fetal membranes and placenta. The 63Ni radioactivity in fetal blood was higher than that in maternal blood from 3 to 24 h. The fetal liver, heart, stomach and brain exhibited higher 63Ni radioactivity than the corresponding maternal organs from 6 to 24 h. However, maternal kidney consistently exhibited significantly higher 63Ni radioactivity than the fetal kidney. The 63Ni in fetal lung and amniotic fluid increased throughout the period of experimental observation. These observations corroborated previous finding that nickel is actively transferred across the blood-placenta-barrier into fetus, but hardly from fetus to mother. Moreover, these results suggest that the placenta has a high affinity for nickel and its barrier does not protect the fetus from nickel exposure. The fact that nickel concentrations are higher in most fetal organs and tissues than in corresponding maternal organs and tissues in late gestation indicates that, unlike the dam, fetuses lack effective means for getting rid of excessive nickel due to its confined environment and relatively weak kidney functions. The situation is exacerbated by mother-to-fetus unidirectional transfer. Consequently, the fetuses are particularly vulnerable to the damaging effects of nickel. [Copyright &y& Elsevier]

Abstract: Objective: maternal mortality remains a major public health problem in many countries. The aim of this paper is to describe the progress made in maternal health care in Zhejiang Province, China over 20 years in reducing the maternal mortality ratio (MMR). Setting: Zhejiang Province is located on the mid-east coast of China, approximately 180km south of Shanghai, and has a population of 49 million. Almost all mothers give birth in hospitals or maternal and infant health institutes. Method: the annual maternal death audit reports from 1988 to 2008 were analysed. These reports were prepared annually by the Zhejiang Prenatal Health Committee after auditing each individual case. Measurements and findings: China has made considerable progress in reducing the MMR. Zhejiang has one of fastest developing economies in China, and since the 86 economic reforms of 1978, health care has improved rapidly and the MMR has declined. During the 1988–2008 period, 2258 maternal deaths were reported from 8,880,457 live births. During these two decades, the MMR decreased dramatically from 48.50 in 1988 to 6.57 per 100,000 in 2008. The MMR in migrant women dropped from 66.87 in 2003 to 21.67 per 100,000 in 2008. The rate of decline was more rapid in rural areas than in the city. There has been a decline in the proportion of deaths with direct obstetric causes and a corresponding increase in the proportion of indirect causes. The proportion of deaths classified as preventable has declined in the past two decades. Social factors are important in maternal safety, and on average 26.8% of maternal deaths were influenced by these factors. Conclusion: as the economy was developing, maternal safety was made a priority health issue by the Government and health workers. The provincial MMR has dropped rapidly and is now similar to the rates in developed countries and lower than that in the USA. However, more work is still needed to ensure that all mothers, including migrant workers, continue to have these low rates. [ABSTRACT FROM AUTHOR]

Abstract: To elucidate the cytotoxicity mechanism of Garnoderma triterpenes, a chemoproteomic study using five purified ganoderic acids, ganoderic acid F (GAF), ganoderic acid K (GAK), ganoderic B (GAB), ganoderic acid D (GAD) and ganoderic acid AM1 (GAAM1) was conducted. GAF, GAK, GAB, GAD and GAAM1 treatment for 48 h inhibited the proliferation of HeLa human cervical carcinoma cells with IC50 values of 19.5±0.6μM, 15.1±0.5μM, 20.3±0.4μM, 17.3±0.3μM, 19.8±0.7μM, respectively. The protein expression profiles of HeLa cells treated with each ganoderic acid at dose of 15μM for 48h were checked using two-dimensional electrophoresis (2-DE). The possible target-related proteins of ganoderic acids, i.e. proteins with same change tendency in all five ganoderic acids-treated groups compared with control, were identified using MALDI-TOF MS/MS. Twelve proteins including human interleukin-17E, eukaryotic translation initiation factor 5A (eIF5A), peroxiredoxin 2, ubiquilin 2, Cu/Zn-superoxide dismutase, 14-3-3 beta/alpha, TPM4-ALK fusion oncoprotein type 2, PP2A subunit A PR65-alpha isoform, nucleobindin-1, heterogeneous nuclear ribonucleoprotein K, reticulocalbin 1 and chain A of DJ-1 protein were identified. Ganoderic acids might exert their cytotoxicity by altering proteins involved in cell proliferation and/or cell death, carcinogenosis, oxidative stress, calcium signaling and ER stress. [Copyright &y& Elsevier]

Abstract: The effects of gestational age and dose of nickel exposure on regulating and influencing placental transfer were investigated. Pregnant rats on gestational day (GD) 12, 15 or 20 were injected intraperitoneally with saline, 64, 320 or 640kBq/kg body weight of 63Ni. Twenty-four hours after administration, samples were harvested from each for measurement of radioactivity by liquid scintillation counting and for autoradiography. In placenta, amniotic fluid and fetal membrane, 63Ni concentrations increased with increasing doses and gestational age. In fetus, 63Ni concentrations reached a maximum on GD 15 and then declined on GD 20 although they maintained a dose-dependency for each GD group. In fetal blood on GD 20, 63Ni concentration increased dose-dependently and was higher than in maternal blood. The autoradiographs demonstrated that 63Ni radioactivity was located within placental basal lamina, fetal bones and most organs. These findings suggest that the nickel uptake, retention and transport in placenta increase dose- and gestation age-dependently, and nickel transfer through placental barrier is primarily from mother into the fetus, but hardly from fetus to mother. [Copyright &y& Elsevier]

Isolated cases of extracorporeal membrane oxygenation (ECMO) in patients with hepatopulmonary syndrome (HPS) undergoing liver transplantation (LT) have been reported with increasing frequency. We aimed to systemically review and synthesize the available literature on ECMO use in this population. A systematic literature review of the PubMed, Web of Science, Cochrane Library, and Embase databases (end-of-search date: November 14, 2021) was conducted in accordance with the PRISMA statement. Eligible studies presented clinical parameters and outcomes of adult or pediatric patients with HPS receiving ECMO support at the time of, or following, LT. Sixteen studies from 4 continents reporting on 17 patients who were initiated on ECMO prior to (n = 2), during (n = 1) or after LT (n = 14) were included. Nine of the 16 studies were published between 2019 and 2021. The median pre-LT PaO 2 was 38.0 mmHg (IQR 35.0–52.0). The median time from LT to ECMO initiation was 7 days (IQR, 3–12). Six patients (50%, n = 6 of 12) were extubated post-LT, before deterioration, development of refractory hypoxemia, and initiation of ECMO. Most patients were cannulated with a venovenous configuration (75%, n = 12 of 16). Most patients cannulated with a venoarterial or veno-arterial-venous strategy (75%, n = 3 of 4) had concurrent hemodynamic instability. The median total time on ECMO was 13 days (IQR 10–29). Using linear regression, for patients cannulated postoperatively, each day between LT and ECMO initiation was associated with a 3.5-day increase in total ECMO duration (95%CI: 2.23–4.73, p < 0.001, R2 = 73.7%). The median postoperative intensive care unit length of stay was 40 days (IQR, 37–61) and hospital length of stay was 59.5 days (IQR 42–77). 82.4% of patients (14 of 17) survived to discharge. ECMO is feasible in patients with HPS undergoing LT and appears to be associated with better outcomes compared to other causes of cardiopulmonary failure in LT patients. As the volume of experience grows, ECMO may become a central part of perioperative support in LT patients with severe HPS. • ECMO use in LT patients with HPS and refractory hypoxemia is increasingly reported. • Median time from LT to ECMO initiation was 7 days. • Median ECMO duration was 13 days. • Fourteen of 17 (82.4%) patients survived to discharge. • ECMO for severe HPS may have better outcomes than ECMO for other indications in LT. [ABSTRACT FROM AUTHOR]

PURPOSE: Platelet-rich plasma (PRP) has been widely applied to promote tissue healing and used as a novel injectable scaffold in bone tissue engineering. However, there is no report about its feasibility to support chondrogenesis. This study aimed to investigate the feasibility of a PRP carrier to deliver chondrocytes and regenerate cartilage tissues in a rabbit model via injection. MATERIALS AND METHODS: Eight New Zealand rabbits were divided into a chondrocytes/PRP group (n = 4) and a PRP-alone group (n = 4). Chondrocytes harvested from the auricular root of New Zealand rabbits were cultured and harvested. The chondrocytes were then mixed with PRP solution to generate chondrocytes/PRP composites with final cellular density of 5.0 x 10(7)/mL. Bovine thrombin was used as a cross-linking agent to gel chondrocytes/PRP composites, then, the composites were injected subcutaneously into the dorsal tissue of cell donor animals. As controls, PRP alone was injected into another 4 rabbits. At the second month after injection, rabbits were prepared for magnetic resonance imaging. The samples were then harvested for macroscopical examination, histological analysis, and glycosaminoglycan quantification. RESULTS: Two months after injection, the hard knobbles were easily palpated under the dorsal skin of the animals in the chondrocytes/PRP group, and magnetic resonance images showed the presence of cartilage-like tissues. In histological analysis, formation of new cartilage was observed in the chondrocytes/PRP composites. Safranin-O staining and Masson's trichrome staining showed proteoglycan and collagen were produced in matrices. In contrast, no tissue formed in the PRP-alone group. CONCLUSIONS: This study suggests the feasibility of using PRP as injectable scaffold seeded with chondrocytes to regenerate cartilage and showed the potential of using this method for the reconstruction of cartilage defects.Copyright © 2007 by the American Association of Oral and Maxillofacial Surgeons [ABSTRACT FROM AUTHOR]

Abstract: Osteochondroma is rarely found in oral and maxillofacial regions. The majority of reported osteochondromas occurred in mandibular areas; their occurrence in bones developed by intramembranous ossification is extremely rare. In this report, a case of osteochondroma arising from the pterygoid process of the sphenoid is described. Radiological investigations showed a large bony mass under the left great wing of the sphenoid and involving the left parapharyngeal space. The tumour was compressive to the mandibular ramus and pharyngeal cavity, causing marked disturbance of mouth opening and secretory otitis media. Histopathological examination confirmed the lesion to be osteochondroma. [Copyright &y& Elsevier]

Abstract: The size and specific shape of bone grafts are important for jaw reconstruction. In this experiment, segmental bone grafts were engineered in a predetermined shape via seeding osteoblast precursor cells into titanium mesh–coral composite scaffolds. Titanium meshes were moulded into the shape of a column with length 12mm and diameter 8mm. The column was filled with natural coral granules and the complex acted as a cell-seeding scaffold. About 4×107 osteoblast precursor cells in 200μl cell-culture medium were seeded into each of six scaffolds and incubated in vitro for 2 days. Then, the composites were implanted subcutaneously into the backs of nude mice and incubated in vivo. Two months after implantation, the animals were killed and new bone formed in the scaffolds was investigated by gross inspection, X-ray examination, histological observation and mechanical testing. The results showed that newly formed tissue was red and presented the gross appearance of bone, and kept the original shape of the column. Titanium mesh was situated on the surface of the bone graft. An X-ray blocking shadow was observed in and around the titanium scaffolds; most of the coral granules had been absorbed. Histological observation demonstrated a large amount of new bone formed and integrated well with titanium mesh. Mechanical testing showed that new bone improved the mechanical property of the graft significantly. In conclusion, a titanium mesh–coral composite scaffold with osteoblast precursor cells is an efficient means to engineer segmental bone, possessing the desired shape and mechanical strength. [Copyright &y& Elsevier]

Abstract: Aims: The aim of this study was to investigate the relationship between RhoA expression and clinic pathological parameters of hepatocellular carcinoma (HCC), and to evaluate the prognostic value of RhoA for HCC patients. Methods: Three methods, including reverse transcription and polymerase chain reaction, Western blot and immunohistochemical staining were employed to detect RhoA expression in 128 HCC specimens. The correlation between RhoA expression and clinicopathologic outcome, and prognostic value of RhoA for HCC patients were analyzed. Results: HCC tissues revealed significantly higher levels of both RhoA mRNA and protein than pericarcinomatous liver tissues (PCLT) (P =0.001). The mRNA and protein expression levels of RhoA in HCC tissues showed strongly positive correlation (correlation coefficient=0.712, P =0.01). There was significant correlation among RhoA mRNA and protein overexpression, and venous invasion (P =0.009 and P =0.040, respectively) and cell differentiation (P =0.021 and P =0.017). HCC patients with RhoA-positive expression showed a significantly poor prognosis than those with RhoA-negative expression (P =0.039). Conclusions: Our data strongly suggested that increased RhoA expression in HCC correlated with venous invasion and cell differentiation of HCC, overexpression of RhoA indicated a poor prognosis in HCC patients. [Copyright &y& Elsevier]

Objective: To evaluate the efficacy and tolerability of fluticasone propionate (FP) hydrofluoroalkane (HFA) in children age 1 to < 4 years with asthma.Study Design: Children were assigned (2:1) to receive FP HFA 88 mug (n = 239) or placebo HFA (n = 120) twice daily through a metered-dose inhaler with a valved holding chamber and attached facemask for 12 weeks. The primary efficacy measure was mean percent change from baseline to endpoint in 24-hour daily (composite of daytime and nighttime) asthma symptom scores.Results: The FP-treated children had significantly greater (P < or = .05) reductions in 24-hour daily asthma symptom scores (-53.9% vs -44.1%) and nighttime symptom scores over the entire treatment period compared with the placebo group. Daytime asthma symptom scores and albuterol use were slightly more decreased with FP than with placebo; however, the differences were not statistically significant. Increases in the percentage of symptom-free days were comparable. The percentage of patients who experienced at least 1 adverse event was similar in the 2 groups. Baseline median urinary cortisol excretion values were comparable between the groups, and there was little change from baseline at endpoint. FP plasma concentrations demonstrated that systemic exposure was low.Conclusions: FP HFA 88 mug twice daily was effective and well tolerated in pre-school-age children with asthma. [ABSTRACT FROM AUTHOR]

Mice with a targeted disruption of adenosine A3 receptor (A3AR) gene were assessed for their nociceptive threshold and for their localized inflammatory response following carrageenan injected into the hindpaw. Under basal conditions no difference was seen between A3AR knock-out (A3AR−/−) and wild-type (A3AR+/+) mice in nociceptive response to mechanical or heat stimuli. The antinociceptive response to the intrathecal adenosine analogue R-phenylisopropyl adenosine (R-PIA) was also unchanged in the A3AR−/− mice. In contrast, heat hyperalgesia, plasma extravasation and edema following carrageenan-induced inflammation in the hind paw were significantly reduced in A3AR−/− mice compared to the A3AR+/+ controls. Thus, mice lacking A3AR had deficits in generating the localized inflammatory response to carrageenan, supporting a pro-inflammatory role of A3AR in peripheral tissues. However, no evidence for a role of A3AR in nociception and the antinociceptive effect of R-PIA was found. [Copyright &y& Elsevier]

Objective: The purposes of this study were to determine (1) whether uterine tissues as well as the fetal placenta are involved in the development of prostaglandin-synthesizing capacity associated with impending labor in pregnant sheep and (2) whether the key enzyme of prostaglandin synthesis, prostaglandin H synthase 2, is differentially expressed in the different intrauterine tissues during late gestation and in association with labor.Study Design: Myometrium, endometrium, and fetal placenta were removed from ewes at 95 days' gestation, (n = 3), 101 to 110 days' gestation (n = 3), 111 to 120 days' gestation (n = 3), 121 to 130 days' gestation (n = 3), 131 to 140 days' gestation (n = 3), and 141 to 145 days' gestation (n = 4) and from ewes in spontaneous term labor at 143 to 147 days' gestation (n = 4). Expressions of prostaglandin H synthase 2 messenger ribonucleic acid and protein were determined by Northern blot and Western blot analyses. Prostaglandin H synthase 2 was localized in the fetal placenta by immunohistochemical means.Results: Levels of both prostaglandin H synthase 2 messenger ribonucleic acid and protein increased gradually from 115 days' gestation in the fetal placenta and from 131 days' gestation in the endometrium. A further and more significant increase in prostaglandin H synthase 2 concentration occurred in the placenta and endometrium during spontaneous term labor. In contrast, myometrial concentrations of prostaglandin H synthase 2 messenger ribonucleic acid and protein remained at steady basal levels during the course of pregnancy and increased only during labor. Prostaglandin H synthase 2 was localized in the trophoblast cells of the fetal placenta.Conclusions: Tissue-specific ontogenic expression of prostaglandin H synthase 2 was observed in myometrium, endometrium, and placenta during late ovine gestation and spontaneous term labor. Fetal placenta and endometrium showed increased expression of prostaglandin H synthase 2 messenger ribonucleic acid and protein during late ovine gestation, whereas myometrial prostaglandin H synthase 2 concentration remained low throughout late gestation. Prostaglandin H synthase 2 concentrations in the myometrium, endometrium, and placenta are all upwardly regulated during labor. [ABSTRACT FROM AUTHOR]

Objective: Our purpose was to determine differential effects of natural and synthetic glucocorticoids on cytochrome 17alpha-hydroxylase and cytochrome P-450 side-chain cleavage messenger ribonucleic acid in the sheep placenta and to determine whether feed-forward effects during labor are involved in further inducing placental cytochrome 17alpha-hydroxylase.Study Design: Sheep underwent placement of myometrial electromyogram electrodes while they were under general anesthesia at 117 days' gestation. At 125 days' gestation either saline solution (early control animals not in labor, n = 5), 0.48 mg betamethasone during 48 hours (n = 7), 0.48 mg dexamethasone during 48 hours (n = 7), or 55 mg cortisol during a maximum of 96 hours (n = 4) was directly administered intravenously to the fetus. Necropsies were performed at 127 to 129 days' gestation. We also studied 6 ewes in spontaneous term labor at 143-147 days' gestation, 6 term control animals not in labor at 140 to 147 days' gestation, and 6 sheep in which myometrial activity was inhibited by intravenous infusion to the ewe of the selective cyclooxygenase 2 inhibitor nimesulide 9 hours after the onset of labor beginning at 147 to 148 days' gestation. Total fetal placental ribonucleic acid was analyzed by Northern blot with complementary deoxyribonucleic acid probes for cytochrome 17alpha-hydroxylase, cytochrome P-450 side-chain cleavage, and 18S ribosomal ribonucleic acid to correct for loading.Results: Placental cytochrome 17alpha-hydroxylase messenger ribonucleic acid was detectable neither in term control animals not in labor nor in early control animals not in labor. Placental cytochrome 17alpha-hydroxylase messenger ribonucleic acid was induced in spontaneous term labor and all cortisol-infused sheep in labor with respect to term control animals not in labor and early control animals not in labor (P <.01). All betamethasone-infused sheep had myometrial contraction activity; however, only 4 of 7 had detectable placental cytochrome 17alpha-hydroxylase messenger ribonucleic acid. Placental cytochrome 17alpha-hydroxylase messenger ribonucleic acid was not detected in dexamethasone-infused sheep, even the 2 that had myometrial contractions. After reversal of the progression of spontaneous labor with nimesulide placental cytochrome 17alpha-hydroxylase messenger ribonucleic acid was significantly lower than the spontaneous term labor group (without nimesulide treatment). The placentas from all animals expressed cytochrome P-450 side-chain cleavage messenger ribonucleic acid, but no changes were associated with either gestational age studied (130 versus > 140 days' gestation) or glucocorticoid-induced premature labor and spontaneous term labor.Conclusions: (1) In sheep the expression of placental cytochrome 17alpha-hydroxylase is tightly associated with spontaneous term labor, and active synthesis of placental cytochrome 17alpha-hydroxylase is required during the progression of labor. (2) Cortisol is a more potent stimulator of placental cytochrome 17alpha-hydroxylase messenger ribonucleic acid in sheep than are synthetic glucocorticoids. (3) Betamethasone has a greater effect in inducing labor in sheep than does dexamethasone, possibly mediated through placental cytochrome 17alpha-hydroxylase. [ABSTRACT FROM AUTHOR]

Objective: Our purpose was to investigate, first, whether there were changes in the abundance of prostacyclin synthase protein in intrauterine tissues of pregnant ewes in association with spontaneous term labor. Second, we examined the effect of either estradiol or progesterone, or both, on regulation of prostacyclin synthase protein abundance in uterine tissues using an ovariectomized nonpregnant sheep model.Study Design: The abundance of prostacyclin synthase protein was quantified by Western blot analysis in the myometrium, endometrium, and placenta of pregnant ewes in spontaneous term labor (n = 6) and term control ewes not in labor (n = 6). The changes of prostacyclin synthase in the myometrium and endometrium of 20 ovariectomized nonpregnant sheep (n = 5 for each group) were evaluated after treatment with estradiol, progesterone, or both.Results: Prostacyclin synthase protein was present in pregnant and nonpregnant sheep myometrium, endometrium, and placenta at a molecular weight of about 55 kd. At spontaneous term labor the level of prostacyclin synthase decreased in endometrium (P <.05), increased in myometrium (P <.05), and remained unchanged in placenta. Estradiol and progesterone had no effect on prostacyclin synthase protein abundance in nonpregnant ovine endometrium and myometrium.Conclusions: The decrease in prostacyclin synthase in pregnant sheep endometrium during labor may indicate paracrine interactions between the endometrium, the myometrium, fetal membranes, or a combination of these. The significant increase of prostacyclin synthase in pregnant sheep myometrium at spontaneous term labor may contribute to the increased uterine sensitivity to oxytocin or stimulate vasodilatation during labor to increase myometrial blood flow. Neither estradiol nor progesterone at the dosages studied changed prostacyclin synthase expression in the nonpregnant myometrium and endometrium. The molecular mechanism or mechanisms that differentially regulate prostacyclin synthase expression in pregnant uterine tissues merit further study. [ABSTRACT FROM AUTHOR]

Objective: Our purpose was to investigate the temporal relationship between delta4-androstenedione-induced preterm switching of myometrial activity patterns from contractures to contractions and maternal plasma estradiol and oxytocin concentrations in the 0.8 gestation rhesus monkey.Study Design: Eight rhesus monkeys (132 to 136 days' gestation) were instrumented under halothane with femoral artery and vein catheters and uterine electromyogram electrodes. At 138 to 142 days' gestation baseline maternal femoral artery blood samples for estradiol and oxytocin measurement were taken at 30-minute intervals for 7 hours, starting 2 hours before the onset of darkness. The day after baseline sampling a continuous intravenous delta4-androstenedione infusion (0.3 mg . kg-1 .hr-1 in 10% intralipid at 0.25 ml . hr-1) was started in four monkeys, while four monkeys were infused intravenously with intralipid alone. The sampling regimen was then repeated at 1 and 3 days after the start of the delta4-androstenedione or intralipid infusion. Contractions were counted and estradiol and oxytocin were measured by radioimmunoassay.Results: Androstenedione promoted a premature nocturnal increase in myometrial contractions in conjunction with an increase in maternal plasma concentrations of estradiol and oxytocin, which were of similar magnitude to those measured in spontaneous term labor. The increase in maternal estradiol preceded the increase in maternal oxytocin levels and myometrial contractions. The onset of the increase in maternal plasma oxytocin was closely associated with the appearance of myometrial contractions after delta4-androstenedione treatment. In contrast, no sustained premature contractions or changes in estradiol and oxytocin occurred in intralipid-treated monkeys.Conclusions: We conclude that in the 0.8 gestation rhesus monkey (1) the increase in maternal plasma estradiol precedes the increase in maternal plasma oxytocin after delta4-androstenedione treatment and (2) delta4-androstenedione-induced preterm myometrial contractions are closely associated in time with physiologic increases in maternal plasma oxytocin concentrations. [ABSTRACT FROM AUTHOR]

Objective: Our purpose was to investigate whether there is an increase in messenger ribonucleic acid for estrogen receptor in critical maternal or fetal tissues in the last third of pregnancy and during labor in sheep.Study Design: Estrogen receptor messenger ribonucleic acid was measured by Northern hybridization analysis in fetal-placental and maternal uterine tissues during the last third of pregnancy and during spontaneous or cortisol-induced labor in sheep. Statistical differences were assessed with two-way analysis of variance.Results: No estrogen receptor messenger ribonucleic acid was observed in amnion or chorion in any animal studied. There were no gestational age related changes in estrogen receptor messenger ribonucleic acid in any tissues between 100 and 145 days' gestation. During spontaneous and cortisol-induced labor estrogen receptor messenger ribonucleic acid increased significantly (p < 0.05) in myometrium, endometrium, and cervix. No increase was observed in the fetal placental cotyledon and mesometrium. Estrogen receptor messenger ribonucleic acid was markedly decreased (p < 0.05) in myometrium and endometrium after fetal adrenalectomy.Conclusion: An increase in estrogen receptor messenger ribonucleic acid in association with labor may contribute part of the mechanism by which estrogens exert their influence on the process of parturition. [ABSTRACT FROM AUTHOR]