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The objective of this study was to evaluate the effect of apatinib on the pharmacokinetics of venlafaxine and O-desmethylvenlafaxine in SD rats and the inhibitory effects of apatinib on venlafaxine in rat and human liver microsomes. Twenty-one SD male rats were randomly divided into three groups (n = 7): group A (multiple dose of 40 mg/kg apatinib for 7 days), group B (single dose of 40 mg/kg apatinib) and group C (the control group). All samples were measured by UPLC-MS/MS. The results indicated that a single dose of apatinib increased the AUC(0-t) , AUC(0-∞) and Cmax of both venlafaxine and O-desmethylvenlafaxine significantly, while Vz/F and CLz/F were decreased. As for group A, only AUC(0-t) and CLz/F of venlafaxine were changed, while no parameters of O-desmethylvenlafaxine were altered. In addition, apatinib was determined to be a mixed inhibitor of venlafaxine.

Orthotropic steel decks are vulnerable to fatigue cracking in welded connections and complex geometrical details. A total of three fatigue tests were conducted on segments of orthotropic steel deck to evaluate the fatigue performance of trough-to-crossbeam connections with various cut-out configurations. In the tests, the specimens were subjected to cyclic three-point bending load and the fatigue cracks were more likely to initiate from the cope holes in the crossbeam web rather than the trough-to-crossbeam fillet welds. Three-dimensional finite element models (FEM) of the specimens were built and validated by the measured deflections and stresses. Using the validated FEM, the characteristic stresses based on the theory of critical distances (TCD) were calculated for the stress concentrations along the cope holes. The fatigue crack initiation life, predicted by the TCD-based stress combined with the plain material S–N curve, agreed reasonably with the fatigue test results. The TCD method could further form a basis of fatigue crack propagation analysis using the fracture mechanics approaches.

A solid-phase microextraction (SPME) fiber coated with poly(methacrylic acid-ethylene glycol dimethacrylate) coupled to GC with a micro electron-capture detector was developed for the determination of four chlorphenols in water samples for the first time. A novel and simple method for the preparation of this novel SPME fiber was proposed by copolymerization of methacrylic acid and ethylene glycol dimethacrylate in an appropriate solvent using a glass capillary as a "mold". The factors affecting the polymerization were optimized in detail. Furthermore, the extraction performance of the poly(methacrylic acid-ethylene glycol dimethacrylate) fiber was evaluated. Moreover, experimental headspace-SPME parameters, such as extraction temperature, extraction time, salt concentration, stirring speed, and pH, were optimized by orthogonal array experimental designs. Under the optimized conditions, the target analytes were linear in the range of 0.2-50 ng/mL, and the correlation coefficients were all greater than 0.99. RSD was less than 8.9%, and the detection limits were in the range of 0.1-10 ng/L. Four cholorphenols were detected from tap and lake water samples using the proposed method, with the recoveries of spiked natural water samples were ranged from 91.8 to 110.8, and 90.6 to 111.4% for tap and lake water samples, respectively.

Background and purpose: Spinal dural arteriovenous fistulas (DAVFs) may arise at any level from the foramen magnum to the sacrum. Only a few case series of DAVFs at the foramen magnum have been reported, especially with patients presenting with subarachnoid hemorrhage (SAH). We performed a retrospective study of four such cases and summarize experiences in the diagnosis and surgical treatment of a DAVF at the foramen magnum. Methods: Four male patients, aged from 35 to 51 years, were admitted with severe headache. The cranial computerized tomography scans of all four patients showed SAH, with hemorrhage in the fourth ventricle with or without hemorrhage in the occipital horns of the lateral ventricles. Pre-operative digital subtraction cerebral angiography showed a DAVF at the foramen magnum draining to medullary veins and/or the straight sinus and the confluence of sinuses. Two DAVFs were fed by the vertebral artery, whilst the others were fed by dural branches of the occipital artery and/or the ascending pharyngeal artery. Results: Three patients underwent direct microsurgical electrocoagulation and disconnection of the arteriovenous shunt via an enlargement of the foramen magnum and a hemilaminectomy at C1 by the far lateral suboccipital approach. Post-operative angiography confirmed complete obliteration of the fistula. Conclusions: Cerebral digital subtraction angiography is an effective and accurate method for examination of a DAVF at the foramen magnum. It can be treated effectively and with minimal surgical trauma by microsurgical electrocoagulation and disconnection of the shunt.