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Background: Androgen insensitivity syndrome (AIS) is a disorder of sexual differentiation caused by complete or partial resistance to the biological action of androgens. The common malignant tumors associated with this syndrome are seminomas. However, the risk of malignancy in childhood remains low. Case Report: A 8-month-old child with a female phenotype and a 46, XY karyotype, presented with bilateral inguinal hernia. The patient underwent right radical inguinal orchiectomy with high ligation of the spermatic cord and laparoscopic percutaneous extra-peritoneal herniorrhaphy. Final pathology confirmed a pure yolk sac tumor (YST) from the right testis. Androgen receptor (AR) gene mutation was found in the children. The follow-up ultrasonography shown no recurrence, with serum AFP returned to normal within 3 months. Conclusion: The case we presented is relatively infrequent in the literature with yolk sac tumor in a AIS children presented with a palpable lump inguinal region.

Purpose We performed a systematic review and meta-analysis to compare the safety and efficacy of minimally invasive surgery (MIS) versus open ureteral reimplantation (OUR) in children. Methods Literature searches were conducted to identify studies that compared MIS (laparoscopic ureteral reimplantation or robot-assisted laparoscopic ureteral replantation) and OUR in children. Parameters such as operative time, blood loss, length of hospital stay, success rate, postoperative urinary tract infection (UTI), urinary retention, postoperative hematuria, wound infection, and overall postoperative complications were pooled and compared by meta-analysis. Results Among the 7,882 pediatric participants in the 14 studies, 852 received MIS, and 7,030 received OUR. When compared with the OUR, the MIS approach resulted in shorter hospital stays (I 2 = 99%, weighted mean difference [WMD] –2.82, 95% confidence interval [CI] –4.22 to –1.41; p Conclusion MIS is a safe, feasible, and effective surgical procedure in children when compared with OUR. Compared with OUR, MIS has a shorter hospital stay, less blood loss, and less wound infection. Furthermore, MIS is equivalent to OUR in terms of success rate and secondary outcomes such as postoperative UTI, urinary retention, postoperative hematuria, and overall postoperative complications. We conclude that MIS should be considered an acceptable option for pediatric ureteral reimplantation.

Polyurethane elastomers with amphiphilic ABA tri-block co-polymers as the soft segments robustly show record-high tensile strength and simultaneously increased ductility via producing small and uniform hard domains.

We conducted a systematic review and meta-analysis to compare the efficacy and safety between laparoscopic reduction (LR) and open reduction (OR) of intussusception in infants and children. Literature searches were conducted to identify studies having compared LR and OR for children with intussusception failed to enema reduction. Parameters such as operative time, time to oral intake, length of hospital stay, overall postoperative complications, and recurrence were pooled and compared by meta-analysis. Among the 502 pediatric participants included in the 11 studies, 275 had received LR and 227 received OR. There were shorter length of hospital stays and time to oral intake with the LR approach compared with OR. However, no significant difference was found between LR and OR in the secondary outcome, such as the overall postoperative complications and recurrence. LR is a feasible, safe, and effective surgical procedure alternative to OR for pediatric intussusception. Compared with OR, LR has the advantage of shorter hospital stay and faster time to oral intake. Besides, the overall postoperative complications may be slightly lower in LR. We conclude that LR should be considered an acceptable option for children.

SALL4 is a zinc finger transcription factor that exerts its physiological role during embryo-fetal development. Analyses of SALL4 expression have shown its oncogenic role in precursor B-cell lymphoblastic lymphoma, acute and chronic myeloid leukemia, gastrointestinal, breast, and lung cancers. The aim of this study was to determine the immunohistochemical profile of SALL4 in pediatric yolk sac tumors (YSTs). Immunohistochemistry detection of SALL4 was performed in 22 cases of pediatric YSTs and 10 mature teratomas. The percentage of tumor cells stained was scored as 0, 1+ (1–30% cells), 2+ (31–60%), 3+ (61–90%), and 4+ (> 90%). To compare its sensitivity and specificity with Glypican-3 and α-fetoprotein (AFP), we also stained tumors from these cases for Glypican-3 and AFP. In contrast to AFP and glypican-3, SALL4 staining in more than 90% of the tumor cells was seen in all 22 pediatric YSTs (100% sensitivity) (P

Purpose: Testicular torsion (TT) is a serious surgical emergency. Prompt diagnosis and treatment of TT are essential to improve the incidence of salvaged testes. The aim of this study was to evaluate the historical features, physical examination findings, laboratory tests, and ultrasound examinations in children with TT, as well as to identify the predictors of testicular salvage in children. Materials and Methods: We retrospectively reviewed the records of 136 males who presented with TT to our institution. Clinical findings, physical examinations, laboratory data, color Doppler ultrasound findings, operating results, and the results of follow-up were collected and analyzed. Patients with neonatal torsion, negative scrotal exploration, or testicular appendix torsion were excluded. A multivariable logistic regression model was used to identify predictors of testicular salvage. Receiver operator characteristics analyses were performed to determine the probability of a non-salvageable torsed testis based on time and degree of twisting. Results: A total of 136 children with TT were identified. Patients were aged from 1 to 16 years, with a mean age of 9.7 years (median, 12; range, 1–16 years). The peak incidences of TT were found between ages of 12 and 14 years. Acute TT is significantly more common in the winter. Testicular salvage occurred in 49 (36%) cases. Of the 49 cases of testicular salvage, 5 patients developed subsequent testicular atrophy. Cutoff values of 13.5 h and 530 degrees of torsion would provide sensitivities of 96 and 61%, with specificity of 80 and 70%, respectively. Multivariate analysis showed that time to surgery and degree of testicular twist were correlated with the risk of a non-salvageable testis. Conclusions: Testicular salvage can be predicted by the duration of symptoms along with degree of twisting. Early scrotal exploration based on careful physical examination decreases the risk of misdiagnosis of spermatic cord torsion. A certain percentage of children with TT presenting with lower abdominal pain should have their testicles checked to make sure that they do not have torsion, especially those visitors in cold season.

Intussusception secondary to pathologic lead points (PLPs) is a potential surgical emergency and almost all cases need surgery. The aim of this study was to evaluate the clinical manifestations, physical examinations and surgical outcomes of secondary intussusception (SI) caused by PLPs, as well as to improve the diagnosis and treatment of PLPs in children and infants.We retrospectively reviewed the records of 83 children and infants who were diagnosed with intussusception secondary to PLPs in our institution. The ultimate diagnosis was dependent on histopathological findings under a microscope by a pathologist. Patients were divided into a younger group ( 2 years old) and the older group ( 2 years old) according to age. Patient demographics, clinical manifestations, duration of symptoms, auxiliary examinations, and the presence of pathological lead point were recorded.A total of 83 patients were found with intussusception secondary to PLPs in this study. Patients were aged from 4 days to 14 years, with a mean age of 3.8 years (median 1.5; range 0-14 years). There were 47 cases in the younger group and 36 cases in the older group. The main clinical symptoms were intermittent crying or abdominal pain. PLPs were observed in only ten patients on US (12%). Ten patients underwent enteroscopy examination for further diagnosis, and all the patients had positive findings including seven cases of Peutz-Jeghers syndrome and three cases of benign polyps. Technetium-99 m pertechnetate scans were performed in ten patients and five patients had positive results (50%). Based on the surgical findings, complex/compound is the most common type of intussusception, followed by small intestinal and ileo-colic type. The main types of PLPs were Meckel's diverticulum (n = 31), duplication cyst (n = 19) and benign polyps (n = 13). Meckel's diverticulum and intestinal duplication were the most common causes of secondary intussusception among children younger than 2 years, accounting for 81% (38/47) of the cases. The most common causes of secondary intussusception in children older than 2 years were intestinal polyps, Meckel's diverticulum and Peutz-Jeghers syndrome, accounting for 72% (26/36) of the cases.The presence of a pathological lead point is more likely in older children. The most common types of intussusception secondary to PLPs are complex/compound and small intestinal. Meckel's diverticulum and intestinal duplication were the most common causes of secondary intussusception among younger children and Peutz-Jeghers syndrome and intestinal polyps were commonly seen in older children.

Cryptorchidism is the most common abnormality of male sexual development. For the protection of testicular functions, antioxidants have emerged as novel options. This study aimed to investigate the protective effect of curcumin (Cur), a strong antioxidant, on the Flutamide-induced cryptorchidism testicular tissue.Pregnant rats were randomly allocated to 3 groups (n = 10, each): a control, a model, and a Cur-treated group (100 mg/kg/d). All offspring were delivered by days 21-22 of gestation and the male rats were sacrificed at postnatal birth days (PNDs) PND60. The testicles were separated and weighed, followed by TUNEL staining to detect germ cell apoptosis, an ELISA kit to measure SOD and MDA, and Western blot analysis to evaluate the expression of Bax, Bcl-2, and PCNA.Curcumin administration ameliorated the histological appearance of the testis and greatly reduced the level of apoptosis in cryptorchidism rats' testicular cells. After curcumin treatment, the expression of proliferating cell nuclear antigen (PCNA) was restored in the testis tissues of cryptorchidism rats. Curcumin therapy reduced Bax expression while increasing Bcl-2 expression, according to the molecular study. Curcumin therapy also reduced malondialdehyde (MDA) levels and enhanced superoxide dismutase (SOD) levels in cryptorchidism rats' testis tissue.It can be concluded that curcumin administration significantly reduced the germ cell apoptosis in rats with cryptorchidism, which provides new insight for antioxidant therapy in preserving testicular functions before or after surgery in cryptorchidism.

The carbon fiber reinforced polymer (CFRP) has been widely used in aerospace, automobile and renewable engine. Since CFRPs are prone to cause impact-induced damage such as inner delamination, nondestructive testing methods have been applied to guarantee the safety. Optical pulsed thermography (OPT) is an effective nondestructive testing method. However, in the thermography processing, time and frequency information is not completely linked. In this paper, Hilbert transform is selected as well as integrating with L4 matrix factorization to mine both time–frequency information from thermal sequences. Compared with the pulsed phase thermography (PPT) which is mainly analyzed in frequency domain, the contrast is enhanced through the proposed method. In addition, time–frequency linked matrix factorization characteristics of defects at different depths can be interpreted as a basis for analysis of defects quality. The validity of the proposed method is verified by simulation and experimental results.

Purpose The purpose of this study is to investigate the corrosion behaviour of X70 steel in the presence and absence of various concentrations of inhibitor N-(2-o-Tolyl azophenyl)-acetamide (NTAA) in a CO2 environment. Design/methodology/approach The temperature was set at 80°C, and the flow velocity was 1.5 m/s. The inhibitor concentrations were 10, 20, 30, 60 and 80 ppm, and the CO2 partial pressure was 0.8 MPa. Weight loss method, pitting depth measurement, scanning electron microscopy and electrochemical techniques were used to investigate the inhibitory effects of the inhibitor NTAA. Findings The results showed that a small peak emerged in the curve of the corrosion rate versus inhibitor concentration plot at 20-30 ppm. Polarisation studies revealed that the anodic Tafel slopes changed greatly in the presence of an inhibitor; NTAA behaved as an anode-type inhibitor. At concentrations of 20-30 ppm, the incomplete coverage of the metal surface by inhibitor molecules resulted in macroscopic galvanic corrosion. Originality/value Corrosion behaviour of X70 steel in the presence and absence of various concentrations of an anode-type inhibitor was assessed. Cathodic Tafel slopes are almost unchanged, while the anodic Tafel slopes change significantly with the increase in inhibitor concentration. The corrosion rates of 20 and 30 ppm are almost three times of that of 10 ppm, which is because of the macroscopic galvanic corrosion caused by the inadequate coverage of inhibitor on steel surface.

RNA-binding protein LIN28 is involved in maintaining the pluripotency of embryonic stem cells. It has been detected in different types of testicular and ovarian germ cell tumors (GCTs), but its status in pediatric YSTs (yolk sac tumors) is still unknown. The aim of this study was to determine the immunohistochemical profile of LIN28 in pediatric YSTs. Immunohistochemistry detection of LIN28 was performed in 22 cases of pediatric YSTs and 10 mature teratomas. The percentage of tumor cells stained was scored as 0, 1+ (1–30 % cells), 2+ (31–60 %), 3+ (61–90 %), and 4+ (>90 %). To compare its sensitive and specificity with alpha-fetoprotein (AFP), we also stained AFP in 22 cases of pediatric YSTs and 10 mature teratomas in children. LIN28 staining was high in all 22 pediatric yolk sac tumor (2+ in 1, 3+ in 1, and 4+ in 20), and weak staining of LIN28 was seen in 1 of 10 mature teratomas (1+), 9 of 10 mature teratomas were negative expression. However, the expression of AFP in pediatric YST was lower compared with Lin28 (- in 1, 1+ in 8, 2+ in 12, and 3+ in 1), and weak expression of AFP was seen in 2 of 10 mature teratomas (1+), 8 of 10 mature teratomas were negative. LIN28 had higher intensity expression than AFP in pediatric YSTs (P

Epoxy adhesive as an engineering material has more and more applications in industry. But to date, water resistance of the adhesive is still a very difficult problem to be solved. By mimicking mussel adhesive proteins, dopamine (DA) was applied as one of the two curing agents of epoxy adhesive to improve the water resistance of the adhesive, and the other was phenethylamine (PEA). The effects of the contents of DA on both adhesion property and water absorption of epoxy/PEA/DA adhesives were investigated in detail. The results of lap shear test (LST) showed that the adhesion strength of the epoxy adhesives after the introduction of proper amount of DA was still up to 7 MPa even after the sample was immersed in water for over 230 days. And then the effects of metal ions Zn(II) and Fe(III) on the adhesion properties of the epoxy adhesives were also further studied. It was found that the adhesion strength of the adhesives, when the content of DA was no more than 5 wt%, can be further increased through the complexation of a small quantity of ferric ions with DA. The coordination mechanism of catechol with Fe(III) ions in the system has been investigated by both UV/Vis spectra and XRD curves. The results testified that more bis-catecholate complexes form at high DA: Fe ratios and thus the adhesives have higher cohesion strength for having more regular structures after curing. In a word, the introductions of proper amount of DA and metal ion endow the epoxy adhesive better water resistance and excellent adhesion properties.

We conducted a systematic review and meta-analysis to compare the clinical outcomes between laparoscopic splenectomy and the traditional open splenectomy in children. Literature searches were conducted to identify studies having compared the laparoscopic splenectomy (LS) and open splenectomy (OS) for children. Parameters such as operative time, blood loss, length of postoperative stay, the removal of accessory spleens and postoperative complications including postoperative high fever, acute chest syndrome (ACS), and ileus were pooled and compared by meta-analysis. Among the 922 pediatric participants included in the 10 studies, 508 had received LS and 414 OS. There were shorter length of hospital stays, less blood loss, and longer operative times with the LS approach compared with OS. However, no significant difference was found between LS and OS in the secondary outcome, such as the removal of accessory spleens or postoperative complications including postoperative high fever, ACS, and ileus. LS is a feasible, safe, and effective surgical procedure alternative to OS for pediatric patients. Compared with OS, LS has the advantage of shorter hospital stay and less blood loss. Besides, total postoperative complications may be slightly lower in LS. We conclude that LS should be considered an acceptable option for children.

Background Acute appendicitis is one of the most common emergency requiring operation. As the first discovered coagulation factor, plasma fibrinogen frequently increases with inflammation due to the activation of coagulation. The aim of this retrospective study was to investigate the diagnostic value of hyperfibrinogenemia as a preoperative laboratory marker for appendiceal perforation in patients with acute appendicitis. Materials and methods We identified 455 patients (202 females, 253 males; mean age, 31.7 years) with histologically confirmed acute appendicitis who underwent laparoscopic or open appendectomy. Results of preoperative laboratory values and post-operative histologic results were analysed retrospectively. A multivariate logistic regression model was performed to determine patient's age and laboratory tests associated with perforated appendicitis. Result Mean plasma fibrinogen level of all patients was 3.99 g/L (1.41 SD; range, 1.73–10.6 g/L; median, 3.69 g/L). Patients with appendiceal perforation had a mean fibrinogen level of 5.72 g/L (1.52 SD; range, 3.38–10.04 g/L; median, 5.28 g/L), which was significantly higher than those with nonperforated groups (P = 0.001). Multivariate analysis showed fibrinogen and D-dimer were associated with perforation (P = 0.001, P = 0.014, respectively). Areas under the receiver operating characteristic curve of fibrinogen for discriminating acute perforated appendicitis from non-perforated groups were larger than white blood cell and D-dimer. Conclusions Hyperfibrinogenemia was common in patients with acute appendicitis and fibrinogen may be useful as a predictive factor for appendiceal perforation.

There is an ongoing debate about whether laparoscopic or open herniorrhaphy (LH or OH) is the best choice for inguinal hernia in children. The aim of this study was to compare both of the surgical strategies as regards operative time, recurrence rate, postoperative complications by means of a systematic review, and meta-analysis of the available literatures.A systematic search for randomized clinical trials comparing OH and LH was conducted. Studies were reviewed for quality, inclusion and exclusion criteria, operative time for bilateral and unilateral hernias, recurrence, and complications.Five randomized clinical trials with a total of 553 children (OH 278, LH 275) fulfilled the inclusion criteria and were analyzed in this review. Compared with OH, shorter operative time for unilateral hernias was noted in extraperitoneal approaches' group [95% confidence interval (CI), -6.71 to -3.71; I2=0%] as well as for bilateral hernias (95% CI, -12.18 to -3.79; I2=82%). Besides, less total postoperative complications was found in LH group, especially for major postoperative complications in male children (95% CI, 0.01-0.78; I2=0%). However, no significant difference was observed between LH and OH in patients' recurrence.This meta-analysis favors LH in the repair of bilateral hernias and for unilateral hernias in extraperitoneal approaches' group. Total postoperative complications were significantly reduced in LH, especially for major postoperative complications in male children.

Single-incision laparoscopic appendectomy (SILA) has been considered as an alternative to conventional laparoscopic appendectomy (CLA). The aim of this systematic review and meta-analysis was to compare clinical outcomes between single-incision laparoscopic appendicectomy and conventional laparoscopic appendicectomy in children. An electronic search of EMBASE, PubMed, MEDLINE was performed. Operative time, length of hospital stay, postoperative complications including wound infection, intra-abdominal infection, ileus in SILA and CLA were pooled and compared by meta-analysis. Twelve studies (4 randomized controlled trials, 1 prospective study and 7 retrospective studies) that included 2,109 pediatric patients were studied. Of these patients, 933 and 1,176 patients had undergone SILA and CLA, respectively. There was significant shorter length of hospital stay for SILA compared with CLA in children; however, pooling the results for SILA and CLA revealed no significant difference in operative time and postoperative complications. Compared with CLA, SILA has the advantage of shorter hospital stay. However, SILA failed to show any obvious advantages over CLA in operative time and postoperative complications including wound infection, intra-abdominal infection, and ileus.

Previous studies have raised interest in using the genotyping of CYP2C9 and VKORC1 to guide warfarin dosing. However, there is lack of solid evidence to prove that genotype plus clinical algorithm provides improved clinical outcomes than the single clinical algorithm. The results of recent reported clinical trials are paradoxical and needs to be systematically evaluated. In this study, we aim to assess whether genotype plus clinical algorithm of warfarin is superior to the single clinical algorithm through a meta-analysis of randomized controlled trials (RCTs). All relevant studies from PubMed and reference lists from Jan 1, 1995 to Jan 13, 2014 were extracted and screened. Eligible studies included randomized trials that compared clinical plus pharmacogenetic algorithms group to single clinical algorithm group using adult (≥ 18 years) patients with disease conditions that require warfarin use. We further used fix-effect models to calculate the mean difference or the risk ratios (RRs) and 95% CIs to analyze the extracted data. The statistical heterogeneity was calculated using I(2). The percentage of time within the therapeutic INR range was considered to be the primary clinical outcome. The initial search strategy identified 50 citations and 7 trials were eligible. These seven trials included 1,910 participants, including 960 patients who received genotype plus clinical algorithm of warfarin dosing and 950 patients who received clinical algorithm only. We discovered that the percentage of time within the therapeutic INR range of the genotype-guided group was improved compared with the standard group in the RCTs when the initial standard dose was fixed (95% CI 0.09-0.40; I(2) = 47.8%). However, for the studies using non-fixed initial doses, the genotype-guided group failed to exhibit statistically significant outcome compared to the standard group. No significant difference was observed in the incidences of adverse events (RR 0.94, 95% CI 0.84-1.04; I(2) = 0%, p = 0.647) and death rates (RR 1.36, 95% CI 0.46-4.05; I(2) = 10.4%, p = 0.328) between the two groups. Allocation to genotype plus clinical algorithm may be associated with a significant improvement of the percentage of time within the therapeutic INR range for patients adopting fixed dose of warfarin. The incidence of total adverse events and death rates did not differ between these two groups. Further experiments need to be conducted to confirm these findings.

Novel amido-borate initiators based on imidazolide bridged borate complexes were developed for acrylic adhesives used to bond low surface energy substrates. The focus of this development was examining the shelf life of the acrylic adhesive system as a function of the molecular architecture of the organoboron curative. The two key molecular features which significantly affect stability are: 1) the chain length of the alkyl groups on the boron atom and 2) arrangement of the imidazolide bridged borate structure. The results show that superior shelf life stability can be attained over the conventional trialkyl borane- and tetraalkyl borate-type initiators when this new family of catalysts (imidazolide borate compounds) is incorporated into the adhesive formulation without any harmful effect on cure speed.

In situ fabrication of graphene scaffold-ZrO2 nanofilms is achieved by thermal annealing of Zr-based metal-organic oligomers on SiO2 substrates. The structural similarities of the aromatic moieties in the ligand (phenyl-, naphthyl-, anthryl-, and pyrenyl-) compared to graphene play a major role in the ordering of the graphene scaffolds obtained. The depth profiling analysis reveals ultrathin carbon-pure or carbon-rich surfaces of the graphene scaffold-ZrO2 nanofilms. The graphene scaffolds with ∼96.0% transmittance in the visible region and 4.8 nm in thickness can be grown with this non-chemical vapor deposition method. Furthermore, the heterogeneous graphene scaffold-ZrO2 nanofilms show a low sheet resistance of 17.0 kΩ per square, corresponding to electrical conductivity of 3197 S m(-1). The strategy provides a facile method to fabricate graphene scaffolds directly on high-k dielectrics without transferring process, paving the way for its application in fabricating electronic devices.

We performed a systematic review and meta-analysis to compare the efficacy and safety between single-incision, transscrotal orchidopexy, and the traditional inguinal orchidopexy in children. A systematic search of the electronic databases was conducted to identify studies compared the transscrotal orchidopexy (SO) and inguinal orchidopexy (IO) for children. Parameters, such as operative time, the incidence of patent processus vaginalis, and postoperative complications, including wound infection, testicular atrophy, testicular reascent, hernia, or hydrocele, were pooled and compared by meta-analysis. Among the 1376 children with palpable undescended testes (UDTs) included in the eight studies, 697 had received SO and 679 IO. There were shorter operative times with the SO approach compared with IO. However, no significant difference was found between SO and IO in the incidence of patent processus vaginalis and postoperative complications, including wound infection, testicular atrophy, testicular reascent, and hernia. SO is a safe and effective surgical approach alternative to IO for pediatric UDTs. Compared with IO, SO has the advantage of shorter operative times. Besides, the incidence of postoperative wound infection may be slightly lower in SO. We suggest that SO should be considered as an acceptable option for children with UDTs.

Purpose To systematically review and meta-analyze studies that have compared the clinical outcomes of laparoscopic and open Nissen fundoplication on children. Methods Online databases were searched to identify studies that have compared the laparoscopic Nissen fundoplication (LNF) and open Nissen fundoplication (ONF) on children, looking specifically for operative time, time to full feed, redo fundoplication rates and total postoperative complications including wound infection, retching, and airway complications. Results Of those 916 patients in the 9 selected studies, 557 and 359 patients had undergone LNF and ONF, respectively; and LNF had significant longer operative time and less total postoperative complications including retching and airway complications than ONF. However, no significant difference in time to full feed, wound infection, and redo fundoplication rates was found between LNF and ONF in children. Conclusion LNF is a safe, feasible, and effective surgical procedure alternative to ONF for gastroesophageal reflux in children. Compared with ONF, LNF has the advantage of less total postoperative complications including retching and airway complications. In addition, LNF is comparable to ONF in terms of time to full feed, wound infection, and redo fundoplication rates. Therefore, we conclude that LNF should be regarded as an acceptable option for children.

Crosslinked organic–inorganic hybrid membranes are prepared from hydroxyl-functionalized sulfonated poly(ether ether ketone) (SPEEK) and various amounts of silica with the aims to improve dimensional stability and methanol resistance. The partially hydroxyl-functionalized SPEEK is prepared by the reduction of some benzophenone moieties of SPEEK into the corresponding benzhydrol moieties which is then reacted with (3-isocyanatopropyl)triethoxysilane (ICPTES) to get a side chained polymer bearing triethoxysilyl groups. These groups are subsequently co-hydrolyzed with tetraethoxysilane (TEOS) and allow the membrane to form a crosslinked network via a sol–gel process. The obtained hybrid membranes with covalent bonds between organic and inorganic phases exhibit much lower methanol swelling ratio and water uptake. With the increase of silica content, the methanol permeability coefficient of the hybrid membranes decreases at first and then increased. At silica content of about 6 wt.%, the methanol permeability coefficient reaches a minimum of 7.15 × 10 −7 cm 2 s −1 , a 5-fold decrease compared with that of the pristine SPEEK. Despite the fact that the proton conductivity is decreased to some extent as a result of introduction of the silica, the hybrid membranes with silica content of 4–8 wt.% shows higher selectivity than Nafion117.

A series of covalently crosslinkable organic–inorganic hybrid membranes have been prepared from sulfonated poly(arylene ether sulfone) (SPAES) with pendant propenyl moiety and various amounts of vinyl substituted silica via sol–gel process which are then thermally crosslinked in the presence of benzoyl peroxide (BPO) initiator. The obtained membranes are characterized in terms of oxidative stability, thermal property, ion exchange capacity (IEC), water uptake, swelling ratio in methanol aqueous solution, proton conductivity, and methanol permeability coefficient. The results indicate that the oxidative stability and thermal stability of the hybrid membranes are improved. Moreover, introduction of silica reduces the water uptake and methanol swelling of membranes. The swelling ratio of membranes in 2 mol L −1 methanol aqueous solution at 80 °C slowly decreases from 26 to 19% with the increase of SiO 2 content from 0 to 12 wt.%. Furthermore, with the increase in silica content, the methanol permeability coefficient of the hybrid membranes decreases at first and then increases. When the silica content reaches 8 wt.%, the methanol permeability coefficient is at the minimum of 6.02 × 10 −7 cm 2 s −1 , a 2.64-fold decrease compared with that of the pristine SPAES membrane. Moreover, the proton conductivity is found to be at about 95% of that of pristine polymer at that silica content.

Partially hydroxyl-functionalized sulfonated poly(ether ether ketone) (SPEEK) was synthesized and further reacted with tetrafunctional MY721 epoxy resin to produce crosslinked networks. The crosslinked membranes were characterized in terms of gel fraction, solubility, ion exchange capacity (IEC), water uptake, swelling ratio in aqueous methanol solution, proton conductivity and methanol permeability coefficient. The result shows that all the crosslinked membranes exhibited lower water uptake and methanol swelling ratio compared with pristine SPEEK. Moreover, the methanol permeability coefficient dramatically decreased with the increase of epoxy resin content. The membrane crosslinked with 1 equivalent of epoxy group per hydroxyl group on SPEEK showed 2.43 times lower methanol crossover than pristine SPEEK. Despite the fact that the proton conductivity of crosslinked membranes was decreased to some extent as a result of the introduction of epoxy resin and crosslinking effect, the membrane crosslinked with 1 equivalent of epoxy group still showed a proton conductivity of 0.096 S/cm at 30 °C which could actually meet the requirement for proton exchange membrane fuel cell (PEMFC) applications. Furthermore, the membranes crosslinked with 1–2 equivalents of epoxy resin showed better selectivity than pristine SPEEK and Nafion117 taking into consideration the methanol crossover and proton conductivity comprehensively.

A series of ionically crosslinked composite membranes were prepared from sulfonated poly(arylene ether sulfone) (SPAES) and polybenzimidazole (PBI) via in situ polymerization method. The structure of the pristine polymer and the composite membranes were characterized by FT-IR. The performance of the composite membranes was characterized. The study showed that the introduction of PBI led to the reduction of methanol swelling ratio and the increase of mechanical properties due to the acid–base interaction between the sulfonic acid groups and benzimidazole groups. Moreover, the oxidative stability and thermal stability of the composite membranes were improved greatly. With the increase of PBI content, the methanol permeability coefficient of the composite membranes gradually decreased from 1.59 × 10−6 cm2/s to 1.28 × 10−8 cm2/s at 30 °C. Despite the fact that the proton conductivity decreased to some extent as a result of the addition of PBI, the composite membrane with PBI content of 5 wt.% still showed a proton conductivity of 0.201 S/cm at 80 °C which could actually meet the requirement of proton exchange fuel cell application. Furthermore, the composite membranes with PBI content of 2.5–7.5 wt.% showed better selectivity than Nafion117 taking into consideration the methanol swelling ratio and proton conductivity comprehensively.

A crosslinkable bisphenol monomer, 3,3′-diallyl-4,4′-dihydroxybiphenyl (ABP) was synthesized and then copolymerized with 4,4′-biphenol (BP), 4,4′-dichloro-diphenylsulfone (DCDPS) and 3,3′-disulfonated-4,4′-dichlorodiphenylsulfone (SDCDPS) by means of aromatic nucleophilic substitution reaction to provide a series of crosslinkable sulfonated poly(arylene ether sulfone)s. The copolymers were then thermally crosslinked in the presence of benzoyl peroxide (BPO) initiator. The structure of result polymers was characterized by FTIR and 1 H NMR spectroscopy. The properties of the uncrosslinked and crosslinked membranes were investigated in terms of water uptake, swelling ratio, proton conductivity and methanol permeability. The results showed that all the crosslinked membranes had lower swelling ratio relative to their uncrosslinked counterparts. Furthermore, with the increase of crosslinking extent, the methanol permeability coefficient of the membranes gradually decreased from 1.59 × 10 −6 cm 2 /s to 4.14 × 10 −7 cm 2 /s without much sacrifice in proton conductivity.

Acute appendicitis is one of the most common emergency requiring operation. As the first discovered coagulation factor, plasma fibrinogen frequently increases with inflammation due to the activation of coagulation. The aim of this retrospective study was to investigate the diagnostic value of hyperfibrinogenemia as a preoperative laboratory marker for appendiceal perforation in patients with acute appendicitis.We identified 455 patients (202 females, 253 males; mean age, 31.7 years) with histologically confirmed acute appendicitis who underwent laparoscopic or open appendectomy. Results of preoperative laboratory values and post-operative histologic results were analysed retrospectively. A multivariate logistic regression model was performed to determine patient's age and laboratory tests associated with perforated appendicitis.Mean plasma fibrinogen level of all patients was 3.99 g/L (1.41 SD; range, 1.73-10.6 g/L; median, 3.69 g/L). Patients with appendiceal perforation had a mean fibrinogen level of 5.72 g/L (1.52 SD; range, 3.38-10.04 g/L; median, 5.28 g/L), which was significantly higher than those with nonperforated groups (P = 0.001). Multivariate analysis showed fibrinogen and D-dimer were associated with perforation (P = 0.001, P = 0.014, respectively). Areas under the receiver operating characteristic curve of fibrinogen for discriminating acute perforated appendicitis from non-perforated groups were larger than white blood cell and D-dimer.Hyperfibrinogenemia was common in patients with acute appendicitis and fibrinogen may be useful as a predictive factor for appendiceal perforation.

To prepare proton conductive membrane for direct methanol fuel cells (DMFC), a novel sulfonated aromatic diamine monomer, 1,4-bis(4-amino-2-sulfonic acid-phenoxy)-benzene (DSBAPB) was synthesized and characterized by 1H NMR and FT-IR. Then a series of sulfonated polyimides (SPIs) were prepared from DSBAPB with 1,4,5,8-naphthalene tetracarboxylic dianhydride (NTDA) and a non-sulfonated diamine, 4,4′-oxydianiline (ODA) via one-step high-temperature polymerization method. The sulfonation degree of the SPIs can be controlled by changing the mole ratio of sulfonated monomer to non-sulfonated monomer. The obtained SPI membranes exhibit desirable proton conductivity ranged from 7.9 × 10−3 to 7.2 × 10−2 S cm−1 and low methanol permeability of less than 2.85 × 10−7 cm2 s−1. Furthermore, the hydrolysis stability of the obtained SPIs is better than the BDSA based SPIs caused by the flexible structure.

The half-sandwich imido tantalum dichloride (η5-C5Me4H)Ta(NtBu)Cl2 is prepared directly from the reaction of the neutral constrained-geometry ligand Me2Si(C5Me4H)(tBuNH) and TaCl5 in refluxing tolu...

Acute appendicitis is the most common emergency abdominal inflammation requiring operation in children. As an acute-phase protein, plasma fibrinogen always increases with inflammation or tissue necrosis. This had brought about the assumption that hyperfibrinogenemia in patients with appendicitis may have a predictive ability for the preoperative diagnosis of appendiceal. Aim of this retrospective study was to assess the diagnostic value of hyperfibrinogenemia as a preoperative laboratory marker for appendiceal perforation in children with acute appendicitis.We screened 466 children (168 girls, 298 boys, mean age, 7.6 years) with histologically confirmed acute appendicitis who received laparoscopic or open appendectomy between January 2012 and April 2014 in a pediatric surgery department of an academic teaching hospital. A retrospective review of the medical records including appendiceal perforation rate and laboratory results was conducted.Mean plasma fibrinogen level of all patients was 4.89 g/L (SD 1.74 g/L, range 1.94-15 g/L, median 4.61 mg/dL). Children with appendiceal perforation had a mean fibrinogen level of 6.18 g/L (SD 1.83 g/L, range 3.02-15 g/L, median 5.79 g/L), which was significantly higher than those with non-perforated children (P = 0.0001). The specificity of hyperfibrinogenemia for appendiceal perforation was 0.82 in comparison with 0.25 for white blood count (WBC) and 0.34 for C-reactive protein (CRP). Sensitivity was 0.74 compared with 0.76 for WBC and 0.94 for CRP.Children with hyperfibrinogenemia and clinical symptoms of appendicitis may be regarded as a higher risk of appendiceal perforation than whose fibrinogen level is normal.

The novel constrained geometry complexes [η5:η1-C5H4EMe2−SiMe2−N(t-Bu)]TiX2, 5a (E = C, X = Cl), 5b (E = C, X = Me), 6a (E = Si, X = Cl), and 6b (E = Si, X = Me), based on dimethylcyclohexadienyl and dimethylsilacyclohexadienyl ligands have been prepared and characterized by 1H and 13C{1H} NMR spectroscopy and single-crystal X-ray structure analysis (5a and 6a). These complexes are the first examples of compounds containing η5 “open” dienyl ligands (pentadienyl or cyclohexadienyl) for titanium in its highest (4+) oxidation state. The crystallographic and electrochemical analysis of these complexes demonstrate that “open” dienyl ligands can be used as a viable replacement for the cyclopentadienyl ring in complexes containing a pendant amido group.

We demonstrate that asymmetric catalytic hydrogenation reactions can be conducted in supercritical CO{sub 2} and that, in some cases, higher enantioselectivities can be achieved in this solvent relative to conventional solvents. These preliminary studies effectively demonstrate the feasibility of conducting highly enantioselective hydrogenation reactions in supercritical CO{sub 2}. Importantly, we have shown that higher enantioselectivities may be achieved in supercritical CO{sub 2} relative to conventional solvents. 16 refs., 2 tabs.

We demonstrate that asymmetric catalytic hydrogenation reactions can be conducted in supercritical CO{sub 2} and that, in some cases, higher enantioselectivities can be achieved in this solvent relative to conventional solvents. These preliminary studies effectively demonstrate the feasibility of conducting highly enantioselective hydrogenation reactions in supercritical CO{sub 2}. Importantly, we have shown that higher enantioselectivities may be achieved in supercritical CO{sub 2} relative to conventional solvents. 16 refs., 2 tabs.