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Amyloid-β (Aβ) protein causes neurotoxicity and its abnormal aggregation into amyloid is a pathological hallmark of Alzheimer's disease (AD). Cellular proteins able to interact with Aβ or its precursor, AβPP (amyloid-β protein precursor), may regulate Aβ production and neurotoxicity. We identified a brain-enriched type I transmembrane protein, tomoregulin (TR), that directly binds Aβ and Aβ oligomers (AβO). TR co-immunoprecipitated with Aβ and AβO in cultured cells and co-localized with amyloid plaques and intraneuronal Aβ in the 5xFAD AD mouse model. TR was also enriched in astrocytic processes reactive to amyloid plaques. Surface plasmon resonance spectroscopy studies showed that the extracellular domain of TR binds to AβO with a high affinity (KD = 76.8 nM). Electron paramagnetic resonance spectroscopy also demonstrated a physical interaction between spin-labeled Aβ and the TR extracellular domain in solution. Furthermore, TR also interacted with AβPP and enhanced its cleavage by α-secretase. Both cellular expression of TR and application of recombinant TR extracellular domain protected N2a neurons from AβO-induced neuronal death. These data provide first evidence that neuronal and astrocytic expression of TR is intimately related to Aβ metabolism and toxicity, and could be neuroprotective through its direct interaction with Aβ and AβPP. [ABSTRACT FROM AUTHOR]

Background: Diabetes mellitus is one of the most important risk factors for atherosclerosis. However, the mechanisms underlying high-glucose-induced atherosclerosis remain unclear. This study was designed to observe the effects of high-glucose stimulation on the permeability of cultured human umbilical vein endothelial cells (HUVECs), and to explore the effects of RhoA-Rho-associated protein kinase (ROCK) signal transduction pathway activation and myosin light chain (MLC) phosphorylation. Methods: HUVECs were cultured in conventional M199 medium to produce endothelial cell monolayers, and stimulated with high-glucose-M199 medium. The transmembrane transport of dextran and THP-1 cells and levels of MLC phosphorylation were measured. The effects of blocking the RhoA-ROCK pathway using dnRhoA or the ROCK inhibitor Y27632 on dextran and THP-1 transport and MLC phosphorylation were observed. Results: Transendothelial migration of dextran and THP-1 cells were significantly increased by stimulation of HUVEC monolayers with high glucose (P < 0.05). This effect was attenuated by treatment with dnRhoA or Y27632. Conclusion: High-glucose stimulation upregulated MLC phosphorylation and increased endothelial permeability by activating the RhoA-ROCK signaling pathway in HUVECs in vitro. [ABSTRACT FROM AUTHOR]

Background/Aims: To investigate the differential expression of RING finger (RNF) proteins in Barrett esophagus (BE) and esophageal adenocarcinoma (EAC). Methods: The differential expression of RNFs in normal esophagus (NE), BE, and EAC was screened using microarray assay. Real-time quantitative polymerase chain reaction (PCR), tissue microarray assay, and Western blot analysis were independently performed to detect the mRNA and protein expression of screened RNFs. Results: The expression of nine RNFs in the BE or EAC was 2-fold higher than those in NE. Among these proteins, the RNF32 and RNF121 expression in BE was 20.3-fold and 16.4-fold higher, respectively, than that in NE, and the expression of RNF24, RNF130, RNF141, RNF139, RNF11, RNF14, and RNF159 was upregulated more than 2-fold compared with NE. The expression of nine RNFs was not only upregulated in the EAC but was also positively related to the RNF expression in BE. The PCR results also indicated increased expression of these RNFs in BE and EAC compared to NE. Furthermore, the mRNA expression of all RNFs, except for RNF141 in EAC, was dramatically higher than those in the BE. Similar results were also obtained from the Western blot analysis. Conclusions: A total of nine RNFs play critical roles in the progression of BE to EAC. [ABSTRACT FROM AUTHOR]

Background/Aims: Upregulated CD64 expression on neutrophils is the most useful marker for acute bacterial infections and systemic inflammation. However, it is unknown whether CD64 is involved in the pathogenesis of acute pancreatitis (AP). This study was designed to determine whether CD64 is implicated in severe acute pancreatitis (SAP), and thus, is a suitable marker for SAP. Methods: SAP was induced in rats with an intraperitoneal injection of L-arginine. CD64 expression in the rat pancreas was determined by quantitative real-time polymerase chain reaction (qRT-PCR) and immunohistochemistry. Additionally, the CD64 mRNA expression in peripheral blood leukocytes from 21 patients with mild acute pancreatitis (MAP) and 10 patients with SAP was investigated at the time of admission and during remission by qRT-PCR. Results: CD64 mRNA and protein expression in the pancreas was significantly higher in rats with SAP, compared to the controls. The CD64 expression was higher in the patients with SAP than in the patients with MAP. During remission, CD64 mRNA decreased in both the MAP and SAP patients. The area under the curve of CD64 expression for the detection of SAP was superior to both the Ranson and the Acute Physiology and Chronic Health Evaluation II scores. Conclusions: The CD64 level was significantly increased in correlation with the disease severity in SAP and may act as a useful marker for predicting the development of SAP. [ABSTRACT FROM AUTHOR]

Background and study aims: Delayed perforation is a rare complication of therapeutic colonoscopy, and it is severe and sometimes lethal. This paper reports on a new minimally invasive method for the treatment of delayed colonic perforation. Patients and methods: Three patients with delayed colonic perforation underwent the therapy, which involved three steps: (1) closure with endoclips and loop, (2) overtube placement, and (3) antibiotic wash through a nasobiliary tube. Results: The procedure was successful in all three patients and no recurrence was observed during 5-41 months of follow-up. Conclusions: Although this study involved only a small number of patients and no control arm, the method involving an overtube appears to be a feasible and effective endoscopic treatment for delayed colonic perforation. [ABSTRACT FROM AUTHOR]

We investigate the evanescent field of a microfiber wrapped by colloidal crystals. The microfiber has the diameter of about 1 µm that is drawn from a single-mode fiber with an alcohol lamp. The colloidal spheres are further attached to the microfiber through thermal evaporation, then they self-assemble to crystal-like structures. The 400 nm, 590 nm, and 710 nm-diameter SiO2 colloidal spheres are used, respectively. The spectral responses are studied theoretically and experimentally, and the results agree with each other. It is revealed that the evanescent field of a microfiber could be modulated by the photonic band-gap of colloidal crystals. This characteristic is very useful in refractive index sensing for liquids. [ABSTRACT FROM AUTHOR]

Zuota is regarded as the king of Tibetan medicine. However, due to the confidentiality of this precious medicine, the scientific characterization of Zuota is very scarce, which limits the pharmacology and biosafety studies of Zuota. Herein, we collected four different Zuota samples from Tibet, Qinghai, Gansu, and Sichuan and characterized them by multiple techniques. Our results showed that Zuota was mainly an inorganic mixture of HgS, sulfur, and graphite. Morphologically, Zuota samples were composed of nanoparticles, which further aggregated into microsized particles. Chemically, the majorities of Zuota were S and Hg (in the forms of HgS and pure sulfur). All samples contained pure sulfur with orthorhombic crystalline. Zuota fromQinghai province had different HgS crystalline, namely, hexagonal crystalline. The others were all face-centered cubic crystalline. Carbon in Zuota NPs was in the form of graphite. The implication to future studies of Zuota was discussed. [ABSTRACT FROM AUTHOR]

Background: Until now, the conventional treatment of stromal tumors has been primarily open surgery or laparoscopic excision. The use of combined laparoscopic/endoscopic surgeries has been investigated, but endoscopic therapy alone has been limited to en bloc resection or nucleus removal of intracavitary tumors with diameters <2 cm. Nonintracavitary and intramural gastric stromal tumors preclude the use of endoscopic resection due to the risk of gastric perforation. This study was designed to show the safety and effectiveness of full-thickness endoscopic resection of nonintracavitary stromal tumors based on our direct experience. Methods: A total of 109 consecutive patients with nonintracavitary gastric stromal tumors <4 cm in diameter underwent surgical treatment; 66 patients received endoscopic surgery and 43 patients received laparoscopic surgery. Results: No significant differences existed between the two groups in terms of demographics and clinical characteristics, and no tumor exceeded 3.5 cm in size. Median operation times (endoscopic group, 53.6 min; laparoscopic group, 139 min) and hospitalization fees of the endoscopic group were significantly lower than those of the laparoscopic group with significant median hospital stays (8 days for endoscopic group; 6 days for laparoscopic group). No intraoperative complications occurred in the laparoscopic group and complete removal of tumors was achieved in the endoscopic group. Postoperative complications occurred in 6 patients of 43 who underwent laparoscopic surgery and 17 patients of 66 who underwent endoscopic surgery, representing a significant difference; the size of the lesion correlated positively with the occurrence of complications. Conclusions: Endoscopic resection is safe and effective for treating nonintracavitary stromal tumors. The endoscopic natural-cavity technique produced less surgical injury to the patients and preserved the anatomy of intra-abdominal structures. In addition, the endoscopic technique reduced operative times, postoperative bleeding, and costs. [ABSTRACT FROM AUTHOR]

Abstract  Arginine vasopressin (AVP) has been shown to directly induce neonatal rat cardiac fibroblasts (CFs) proliferation, a major component involved in cardiac hypertrophy. Herein, we explored whether AVP is also a growth factor for adult rat CFs and, if so, whether the growth effect could be inhibited by simvastatin, a 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor. AVP significantly increased DNA synthesis in adult rat CFs by 73.5 ± 5.1% (P ≤ 0.05), an effect inhibited by V1 receptor antagonist, d(CH2)5[Tyr2(Me), Arg8]-vasopressin. AVP also activated extracellular signal-regulated kinase 1/2 (ERK1/2) as assessed by MBP phosphotransferase activity (5.1 ± 0.6 fold over basal level, P ≤ 0.05) and Western blot analysis, and effects were mimicked by protein kinase C (PKC) activator, phorbol 12-myristate 13-acetate (PMA), but abolished by inhibiting cellular PKC through chronic PMA incubation. In addition, AVP induced PKC activation (27.2 ± 3.8% from a basal value of 9.3 ± 0.7%, P ≤ 0.05). AVP-induced increase in DNA synthesis could be attenuated by the specific inhibitors of ERK1/2 (PD98059), PI3K (LY294002), and AKT (1L-6-hydroxymethyl-chiro-inositol 2-(R)-2-O-methyl-3-O-octadecylcarbonate, HIMO). Simvastatin inhibited the effects of AVP on DNA synthesis, ERK1/2, and PKC activation in a dose-dependent manner. Phosphatidylinositol-3-kinase (PI3K)-dependent AKT activation induced by AVP was also inhibited by simvastatin. The effects of simvastatin on ERK1/2, PKC, and AKT activation and DNA synthesis could be reversed by mevalonate. These results support a growth-inducing effect of AVP on adult rat CFs through ERK and AKT signalings and the growth effect could be attenuated by simvastatin via inhibiting these two pathways. [ABSTRACT FROM AUTHOR]

Understanding chemical composition of organic matter in oil shales in detail is of importance to both organic geochemistry and efficient utilization of oil shales. Because of low boiling point and good penetrability, carbon disulfide was used for extraction of organic matter from solid fossils. In the present study, oil shale samples from Fushun, Longkou and Huadian deposits of China were extracted with carbon disulfide, and extraction solutions were analyzed with gas chromatography and gas chromatography/mass spectrometry. The results show that alkanes, including a series of normal alkanes, isoprenoids and cyclanes, are predominant in extraction solutions. Other compounds detected in the extraction solutions are alkenes, alkylated arenes and organo-oxygen compounds. Normal alkanes are predominant in the carbon disulfide--extractable fraction (CDEF) from Huadian oil shale. CDEF from Longkou oil shale contains much more alkanes than those from other two oil shales, whereas CDEF from Fushun oil shale contains more cyclanes than those from other two oil shale deposits. [ABSTRACT FROM AUTHOR]

In vitro studies have demonstrated that bovine angiogenin (ANG) significantly stimulates both the migration of endothelial cells and the formation of tubelike structures. The aim of this study was to explore whether ANG gene transfer could enhance vascularization, modify left ventricular remodeling, and attenuate cardiac dysfunction in rats with myocardial infarction (MI). We constructed a recombinant adeno-associated virus vector encoding the ANG gene (rAAV-ANG) and evaluated its angiogenic potential after regional transfection by intramyocardial injection immediately after left anterior descending artery ligation in rats. Four weeks after coronary artery ligation, rAAV-ANG transfection upregulated the myocardium ANG protein expression level in both normal and MI rats, and immunohistochemistry showed that the overexpressed ANG was distributed in the cytoplasm of cardiomyocytes. In rats with MI, rAAV-ANG treatment altered left ventricular remodeling, as indicated by a decrease in left ventricular end diastolic diameter, left ventricular end systolic diameter, cardiomyocyte diameter, ventricular weight to body weight ratio and interstitial fibrosis infiltration. We also found an increase in capillary density and partly restored cardiac function in the group receiving rAAV-ANG treatment. These results confirmed that in rats with MI, ANG gene transfer could induce angiogenesis, alter left ventricular remodeling, and attenuate cardiac dysfunction. This study provides a new choice of treatment for ischemic heart disease. [ABSTRACT FROM AUTHOR]

Huperzine A, a novel cholinesterase inhibitor, was found to inhibit the N-methyl-d-aspartate (NMDA) receptors in the brain. In this study, the mechanisms of the NMDA receptor inhibition were investigated using [3H]dizocilpine (MK-801) binding in synaptic membrane of rat cerebral cortex. Changing the concentrations of l-glutamate and l-glycine did not alter the potency of huperzine A. Spermidine caused rightward shift of the concentration–response curve of huperzine A, and considerably increased its IC50 value. Huperzine A did not affect the potency of unlabeled (+)-MK-801 in [3H]MK-801 binding. Saturation binding studies reveal that huperzine A exerts a negative allosteric modulation on the MK-801 binding site within the NMDA receptor-channel. The results suggest that huperzine A is a non-competitive antagonist of the NMDA receptors, acting at one of the polyamine binding sites. [Copyright &y& Elsevier]

The article presents a case study of a 59-year-old male patient who has a medical history of melena and dizziness without prior history of dysphagia. The patient has underwent an endoscopy which shows ulcers on polyps which are potentially bleeding and could result to pharyngeal anesthesia. The article discusses that most patients with fibrovascular polyps of the esophagus and hypopharynx underwent surgical treatment through an endoscopic polypectomy.

Trichoderma isolates were collected from moist soils near a water source in different areas of China. ITS sequences were submitted to MIST (Multiloci Identification System for Trichoderma) and meets the Trichoderma [ITS76] standard. Combined analyses of phylogenetic analyses of both phylograms (tef1-α and rpb2) and morphological characteristics, revealed five new species of Trichoderma, namely Trichoderma hailarense, T. macrofasciculatum, T. nordicum, T. shangrilaense and T. vadicola. Phylogenetic analyses showed T. macrofasciculatum and T. shangrilaense belong to the Polysporum clade, T. hailarense, while T. nordicum and T. vadicola belong to the Viride clade. Each new taxon formed a distinct clade in phylogenetic analysis and have unique sequences of tef1-α and rpb2 that meet the Trichoderma new species standard. The conidiation of T. macrofasciculatum typically appeared in white pustules in concentric rings on PDA or MEA and its conidia had one or few distinctly verrucose. Conidiophores of T. shangrilaense are short and rarely branched, phialides usually curved and irregularly disposed. The aerial mycelium of T. hailarense and T. vadicola formed strands to floccose mat, conidiation tardy and scattered in tufts, conidiophores repeatedly rebranching in dendriform structure. The phialides of T. nordicum lageniform are curved on PDA and its conidia are globose to obovoidal and large. [ABSTRACT FROM AUTHOR]

Salt-alkali tolerance is one of the important breeding traits of Portunus trituberculatus. Identification of molecular markers linked to salt-alkali tolerance is prerequisite to develop such molecular marker-assisted breeding. In this study, Bulked Segregant Analysis (BSA) was used to screen molecular markers associated with salt-alkali tolerance trait in P. trituberculatus. Two DNA mixing pools with significant difference in salt-alkali tolerance were prepared and 94.83G of high-quality sequencing data was obtained. 855 SNPs and 1051 Indels were firstly selected as candidate markers by BSA analysis, out of which, 20 markers were further selected via △index value (close to 0 or 1) and eight of those were successfully verified. In addition, based on the located information of the markers in genome, eight candidate genes related to salt-alkali tolerance were anchored including ubiquitin-conjugating enzyme, aspartate–tRNA ligase, vesicle-trafficking protein, and so on. qPCR results showed that the expression patterns of all these genes changed significantly after salt-alkali stress, suggesting that they play certain roles in salt-alkali adaptation. Our results will provide applicable markers for molecular marker-assisted breeding and help to clarify the mechanisms of salt-alkali adaptation of P. trituberculatus.

A compact wideband coplanar waveguide (CPW) excited slot antenna with dual-circular polarization (DCP) is presented and fabricated in this paper. Two inverted-L-shaped patches are implanted in a square slot to achieve wideband DCP characteristic. The feed line is terminated on an inverted-L-shaped patch. Moreover, two rectangular slots are added on the corners of the antenna to improve the bandwidth of axial ratio (AR) and the voltage standing wave ratio (VSWR). The simulated results show that the designed antenna can generate a good impedance bandwidth of 70.4% and a 3-dB AR bandwidth of 48.6%, respectively. This antenna possesses the qualities of small size, simple structure, and good dual-circular polarization. [ABSTRACT FROM AUTHOR]

Aim: To study the effect of hydrogen sulfide (H2S) on severe acute pancreatitis (SAP) in a rat model., Methods: Sprague-Dawley (SD) rats were administered an intraperitoneal injection of saline containing 20% L-Arg (250 mg/100 g) hourly for over 2 h to induce SAP. The rats were treated with DL-propargylglycine (PAG, 50 mg/kg) or different dosages of NaHS (5 mg/kg, 10 mg/kg, 20 mg/kg or 100 mg/kg). PAG or NaHS was administered 1 h before induction of pancreatitis. Rats were sacrificed 24 h after the last L-Arg injection. Blood and pancreas tissues were collected., Results: The H2S and cystathionine-γ-lyase mRNA levels in SAP rats were significantly lower than those in the control group, and treatment with PAG further reduced the H2S level. Nevertheless, H2S was significantly increased after NaHS administration compared with the SAP group, and the degree of upregulation was associated with the NaHS dosage. NaHS reduced the levels of plasma amylase, interleukin-6 and myeloperoxidase in pancreatic tissue. NaHS suppressed the degradation of IκBα and the activity of nuclear factor-κB, as well as the phosphorylation of PI3K/AKT., Conclusion: H2S plays an anti-inflammatory role in SAP in vivo.

Aim: To investigate the feasibility and safety of pH capsule to monitor pH in patients with gastroesophageal reflux disease (GERD)., Methods: Ninety-one patients with symptoms suggestive of GERD were enrolled in this study, 46 of whom were randomized to the pH capsule group; the remaining 45 patients used the conventional catheter and pH capsule simultaneously. The pH data and traces were recorded via automatic analysis, and capsule detachment was assessed using X-ray images. All of the patients were required to complete a questionnaire regarding tolerance with the capsule., Results: The capsules were successfully attached on the first attempt, and no early detachment of the capsules was observed. Compared to the 24-h pH data recorded with the conventional catheter, the data collected with the pH capsule showed no significant differences in 24-h esophageal acid exposure. The measurements of esophageal acid exposure over 24 h collected with the two devices showed a significant correlation (r(2) = 0.996, P < 0.001). Capsule detachment occurred spontaneously in 89 patients, and 2 capsules required endoscopic removal due to chest pain. The capsule was associated with less interference with daily activity., Conclusion: The wireless pH capsule provides a feasible and safe method for monitoring gastroesophageal reflux and therefore may serve as an important tool for diagnosing GERD.