Theoretical Analysis of Thermophysical Properties of 3D Carbon/Epoxy Braided Composites with Varying Temperature.

A three-dimensional helix geometry unit cell is established to simulate the complex spatial configuration of 3D braided composites. Initially, different types of yarn factors, such as yarn path, cross-sectional shape, properties, and braid direction, are explained. Then, the multiphase finite element method is used to develop a new theoretical calculation procedure based on the unit cell for predicting the impacts of environmental temperature on the thermophysical properties of 3D four-direction carbon/epoxy braided composites. The changing rule and distribution characteristics of the thermophysical properties for 3D four-direction carbon/epoxy braided composites are obtained at temperatures ranging from room temperature to 200 °C. The influences of environmental temperature on the coefficients of thermal expansion (CTE) and the coefficients of thermal conduction (CTC) are evaluated, by which some important conclusions are drawn. A comparison is conducted between theoretical and experimental results, revealing that variations in temperature exert a notable influence on the thermophysical characteristics of 3D four-directional carbon/epoxy braided composites. The theoretical calculation procedure is an effective tool for the mechanical property analysis of composite materials with complex geometries.

Comparison of drug-coated balloon angioplasty versus common balloon angioplasty for arteriovenous fistula stenosis: A systematic review and meta-analysis.

Drug-coated balloons (DCBs) have been used in dialysis patients with arteriovenous fistula (AVF) stenosis, but whether DCBs have advantages over ordinary balloons is still controversial. A meta-analysis was designed to investigate the safety and efficacy of DCBs and common balloons (CBs) in the treatment of AVF stenosis. We searched the PubMed, EMBASE, and China National Knowledge Internet (CNKI) databases for randomized controlled trials that evaluated the comparison of DCB angioplasty versus CB angioplasty for AVF stenosis in dialysis patients and reported at least one outcome of interest. The results showed that the DCB group had a higher first-stage patency rate of the target lesion 6 months [odds ratio, OR = 2.31, 95% confidence interval, CI: (1.69, 3.15), p < .01] and 12 months [OR = 2.09, 95% CI: (1.50, 2.91), p < .01] after surgery. There was no statistically significant difference in all-cause mortality between the two groups at 6 months [OR = 0.85, 95% CI: (0.47, 1.52), p = .58] and 12 months [OR = 0.99, 95% CI: (0.60, 1.64), p = .97]. Compared with CB, DCBs as a new endovascular treatment for AVF stenosis have a higher primary patency rate of target lesions and can delay the occurrence of restenosis. There is no evidence that DCB can increase the mortality of patients.

[Quality standards of Gleditsiae Spina and its decoction pieces].

In view of the current inadequate standards for Gleditsiae Spina in the Chinese Pharmacopoeia, this study put forward some new items of the quality standards of Gleditsiae Spina. Thin-layer chromatography(TLC) was performed for identification with the reference substance of taxifolin and the reference material of Gleditsiae Spina as the control. According to the general principles of the Chinese Pharmacopoeia(2020 edition, Vol. 4), the moisture, total ash content, and alcohol-soluble extract of medicinal materials and decoction pieces of Gleditsiae Spina were determined. The content determination method for medicinal materials and decoction pieces of Gleditsiae Spina was established using high-performance liquid chromatography(HPLC), with taxifolin as the quality control index. Based on the determination results of 30 batches of samples of Gleditsiae Spina from different habitats, the draft quality standards of Gleditsiae Spina were developed, which provided suggestions for the revision of the quality standards of Gleditsiae Spina in the Chinese Pharmacopoeia.

Antiproliferative Phenothiazine Hybrids as Novel Apoptosis Inducers against MCF-7 Breast Cancer.

We designed a series of novel phenothiazine-1,2,3-triazole hybrids by the molecular hybridization strategy and evaluated their antiproliferative activity against three cancer cell lines (MDA-MB-231, MDA-MB-468 and MCF-7). For the structure-activity relationships, the importance of 1,2,3-triazole and substituents on phenyl ring was explored. Among these phenothiazine-1,2,3-triazole hybrids, compound 9f showed the most potent inhibitory effect against MCF-7 cells, with an IC50 value of 0.8 µM. Importantly, compound 9f could induce apoptosis against MCF-7 cells by regulating apoptosis-related proteins (Bcl-2, Bax, Bad, Parp, and DR5). These potent phenothiazine-1,2,3-triazole hybrids as novel apoptosis inducers might be used as antitumor agents in the future.

Neuroprotective effects of Yiqihuoxue calm wind capsule on ischemic stroke in rats.

Stroke remains the third leading cause of death and of adult disability worldwide. Vascular occlusion, followed by ischemic cascade, leads to irreversible tissue injury. Recombinant tissue plasminogen activator is the only FDA approved drug for the current treatment of acute ischemic stroke. However, traditional Chinese medicine has a long history and rich clinical experience in the treatment and rehabilitation of ischemic stroke. Using a classical middle cerebral artery occlusion (MCAO) stroke model, we tested the effectiveness of Yiqihuoxue calm wind (YCW) capsule on neurological function, gross pathology and oxidative stress status in MCAO rats. YCW capsule (3.36 and 6.72 g·kg-1 of crude drug) could significantly lower Longa's score and superoxide dismutase (SOD) level, together with less necrotic cells and infarcted area. In addition to elevated MDA and downregulated iNOS expression, YCW capsule exhibited its neuroprotective effects via free radical scavenging and NO inhibition.

[Chemical constituents from lipophilic parts in roots of Angelica dahurica cv.Yubaizhi].

The chemical constituents from lipophilic parts in the roots of Angelica dahurica cv. Yubaizhi were studied in this paper. The compounds were separated and purified by repeated column chromatographic methods on silica gel and HPLC, and the chemical structures of compounds were determined by spectral data analyses. Thirty-three compounds were obtained and identified as isoimperatorin (1), imperatorin (2), stigmasterol (3), isooxypeucedanin (4), pabulenol (5), psoralen (6), bergapten (7), isodemethylfuropinarine (8), phellopterin (9), osthenol (10), alloimperatorin (11), xanthotoxin (12), xanthotoxol (13), isopimpinellin (14), alloisoimperatorin (15), ß-sitosterol (16), oxyalloimperatorin (17), pabularinone (18), 5-hydroxy-8-methoxypsoralen (19), columbianetin (20), heracol (21), isogosferol (22), 2″R-neobyakangelicol (23), byakangelicin ethoxide (24), byakangelicin (25), oxypeucedanin hydrate (26), uracil (27), umbelliferone (28), bergaptol (29), demethylfuropinarine (30), isobyakangelicol (31), oxypeucedanin ethanolate (32), heraclenol (33). Among them, compounds 8, 10, 17, 21, and 30 were obtained from the roots of title plant for the first time.

Carbon isotopes of C3 herbs correlate with temperature on removing the influence of precipitation across a temperature transect in the agro-pastoral ecotone of northern China.

Plant δ13C-temperature (δ-T) relation has been established in many systems and is often used as paleotemperature transfer function. However, it is still unclear about the exact contributions of temperature variation to plant 13C discrimination because of covariation between temperature and precipitation (aridity), which reduces confidence in reconstruction of paleoclimate. In this study, we measured carbon isotope composition (δ13C) of 173 samples of C3 perennial herbs from 22 sites across a temperature gradient along the 400 mm isohyet in the farming-pastoral zone of North China. The results showed that precipitation obviously affected the correlations of temperatures and foliar δ13C. After removing the influence of precipitation by analysis of covariance (ANCOVA), a more strongly positive relationship was obtained between site-mean foliar δ13C and annual mean temperature (AMT), with a regression coefficient of 0.1636‰/°C (p = .0024). For widespread species, Artemisia lavandulaefolia and Artemisia capillaries, the slopes (or coefficients) of foliar δ13C and AMT were significantly steeper (larger) than those of foliar δ13C and AMT where the precipitation influence was not excluded, whereas the δ-T coefficients of Polygonum persicaria and Leymus chinensis showed little change across the transect after deducting the precipitation effect. Moreover, the positive relationship between temperature and δ13C over the transect could be explained by soil moisture availability related to temperature. Our results may afford new opportunities for investigating the nature of past climate variability.

[Effects on phosphorus fraction distribution in sediment by roots of Vallisneria natans].

The present study explored phosphorus fractions in sediments with the growth of Vallisneria natans. Sediment samples in different layers were collected at 20, 50 and 80 d, and vertical change of several phosphorus fractions were measured in the samples. The root distributions and biomass of the V. natans were measured. Our results showed that roots were distributed between 0 and 14 cm in the experimental device. The average number of roots and average root length were 58 and 5.86 cm. After 80 days growth, the percentage of V. natans root biomass were 45.99%, 32.75%, 16.03% and 5.23% in the sediment with depths of 0-3, 4-6, 7-10 and 11-14 cm. Total phosphorus (TP) content, phosphorus extracted by NaOH (NaOH-P), and organic phosphorus (OP) levels remarkably decreased (P < 0.05) in the area with a high concentration of tape grass roots. The content of phosphorus extracted by HCl (HCl-P), and inorganic phosphorus (IP), showed no significant difference (P > 0.05). The results suggest that V. natans root affects the migration and transformation of phosphorus species in the sediment.

[Distribution of nitrogen in the sediment of Taige south river estuary].

To characterize the distribution of nitrogen in the sediment of Taige south river estuary, column samples of sediments were collected and analyzed in April, 2012. Our results revealed that a synchronized trend existed among the levels of ammonium nitrogen (NH4(+) -N), organic nitrogen (Org-N) and total nitrogen (TN) in the surface layer of sediment. The NH4(+) -N positively correlated with TN and Org-N significantly (P < 0.05) while TN highly significantly correlated with Org-N (P < 0.01). Org-N was the major form of nitrogen, comprising 93.38% of total nitrogen (TN) averagely. Both horizontal and vertical distribution of nitrogen in sediments apparently changed along the distance to stream outlet. In the horizontal dimension in sediments, Org-N and TN decreased progressively as forwarding into the lake in the extending direction of the main stream, while showed a "W"-type fluctuation in the diverged direction away from the main stream. The level of NH4(+) -N decreased rapidly within 100 m to the stream outlet and remained constantly at a lower level beyond 100 m. However, the level of nitrate nitrogen (NO3(-) -N) stabilized within 0-800 m and increased greatly beyond 800 m. In the vertical dimension in sediments, the level of NH4(+) -N increased with increasing depth. As the distance to the stream outlet increasing, the enrichment of NO3(-) -N was enhanced in surface layers rather than in lower subsurface layers. Alternatively, the enrichment of Org-N and TN were reduced in surface layers but enhanced in subsurface layers.

[Influence of two different species of aquatic plant communities on the concentration of various nitrogen forms in sediment of Lake Taihu].

To investigate the spatial distribution of nitrogen in the sediment from both internal and external sites of Potamogeton malaianus and Limnanthemun nymphoides communities, levels of various forms of nitrogen were quantified in sediment samples collected from Gonghu Bay, the southern region and the intermediate area between East and West mountains of Lake Taihu in June 2012. The results showed that: (1) Within the algae-type region in Gonghu Bay, the contents of organic (Org-N) and total nitrogen (TN) in the internal sediment (0-25 cm) from P. malaianus communities were higher than those of the external sediment, by 38.06% and 25.65%, respectively. (2) In the non-algal region, the contents of TN, Org-N, NH4(+)-N and NO3(-) -N in the internal sediments from P. malaianus communities were lower by 43.29%, 50.78%, 7.09% and 10.86% compared to those in the external sediments; for L. nymphoides communities, the contents of TN, Org-N, NH4(+) -N and NO3(-) -N in the external sediments were lower by 4.65%, 4.63%, 5.01% and 2.76% compared to the internal sediments. These values suggested that the promotion in reducing sedimentary nitrogen was more effective by the P. malaianus community than by the L. nymphoides community. (3) A significant positive correlation (P < 0.05, n = 24) was found between pH and TN within the external sediments and between pH and NO3(-) -N within the internal sediments (P < 0.05, n = 24), while a significant negative correlation (P < 0.05, n = 24) was found between pH and NH4(+)-N of both aquatic plant communities. The redox potential (Eh) was also found to be significantly positively correlated with TN in both the internal and external sediments of P. malaianus communities (GMN, P < 0.01, R = 0.922 8 * *; NMN, P < 0.01, R = 0.827 7 * *; GMW, P < 0.05, R = 0.748 9 *; NMW, P < 0.05, R = 0.663 7 *). It is therefore concluded that the presence of aquatic plant communities could impact the physical and chemical properties of the sediments.

[Influence of submerged macrophytes on phosphorus transference between sediment and overlying water in the growth period].

In order to study the process of phosphorus transfer between sediment and overlying water, Hydrilla verticillata and Vallisneria natans were cultured in spring, Potamogeton crispus was cultured in winter. Changes of environmental factors and phosphorus concentrations in water and sediment were investigated. The results indicated that: submerged macrophytes could reduce all phosphorus fractions in the overlying water. Phosphorus concentrations in overlying water maintained in a relative low level in the growth period of submerged macrophytes. The concentrations of total phosphorus (TP) in overlying water of H. verticillata, V. natans and P. crispus were 0.03-0.05, 0.04-0.12, 0.02-0.11 mg x L(-1), respectively. All phosphorus fractions in sediment were reduced. The maximum value between submerged macrophyte and control of H. verticillata, V. natans and P. crispus were 35.34, 60.67 and 25.92 mg x kg(-1), respectively. Dissolved oxygen (DO), redox potential (Eh) and pH in overlying water increased (DO 10.0-14.0 mg x L(-1), Eh 185-240 mV, pH 8.0-11.0) in the submerged macrophytes groups. Submerged macrophytes increased Eh( -140 - -23 mV) and maintained pH(7.2-8.0) in neutral range. The results indicated that submerged macrophytes affected phosphorus transferring between sediment and overlying water through increasing DO, Eh and pH in overlying water, and Eh in sediment.

TNFα-induced IP3R1 expression through TNFR1/PC-PLC/PKCα and TNFR2 signalling pathways in human mesangial cell.

BACKGROUND: Little information is available regarding the mechanisms involved in cytokine-induced type 1 inositol 1,4,5-trisphosphate receptor (IP(3)R1) expression in human mesangial cells (HMCs) in the occurrence of hepatorenal syndrome (HRS). Over-expression of IP(3)R1 would enhance both IP(3)-binding activity and sensitivity. We hypothesize that it is possible that increased IP(3)R1, induced by TNFα, would lead to increased IP(3) sensitivity in response to a variety of vasoconstrictors, and promote HMC contraction and thus lead to reduced GFP, promoting HRS occurrence and development. METHODS: Quantitative real-time polymerase chain reaction and immunoblot assay were used to examine the effects of TNFα on IP(3)R1 mRNA and protein expression. Several inhibitors of kinases, depletion PKC, over-expression of dominant-negative mutant of PKC and non-radioactive PKC assay were used to examine the mechanism of signal transduction of TNFα-regulated IP(3)R1 in HMCs. RESULTS: TNFα increased IP(3)R1 mRNA and protein expression in HMCs, an effect that was blocked by prolonged incubated chronic PMA, D609, safingol and also by transfection with domain-negative PKCα construct. TNFα activated and promoted autophosphorylation of the PKCα. In addition, both anti-TNFR1 and anti-TNFR2 antibodies blocked TNFα-induced IP(3)R1 protein expression, while only anti-TNFR1 antibodies but not anti-TNFR2 antibodies attenuated TNFα-induced PKCα activity. CONCLUSIONS: TNFα increased the expression of IP(3)R1, and this was mediated, at least in part, through the TNFR1/PC-PLC/PKCα and TNFR2 signalling pathways in HMCs.

[Constituents of essential oil from different processing drynesses of Radix Angelicae Dahuricae].

OBJECTIVE: To analyze the constituents of essential oil from different processing drynesses of Radix Angelicae Dahuricae. METHODS: Water steam distillation and GC-MS were used. Relative contents were determined by area. RESULTS: 37 compounds were identified. The constituents of essential oil the constituents from Radix Angelicae Dahuricae by insolation, drying and microwave dryness were similar, but one by dryness after sulfurizing and dryness after perspiring were different. CONCLUSION: Dryness after sulfurizing and dryness after perspiring are not fit for the dryness of Radix Angelicae Dahuricae.

The effects of C-peptide on type 1 diabetic polyneuropathies and encephalopathy in the BB/Wor-rat.

Diabetic polyneuropathy (DPN) occurs more frequently in type 1 diabetes resulting in a more severe DPN. The differences in DPN between the two types of diabetes are due to differences in the availability of insulin and C-peptide. Insulin and C-peptide provide gene regulatory effects on neurotrophic factors with effects on axonal cytoskeletal proteins and nerve fiber integrity. A significant abnormality in type 1 DPN is nodal degeneration. In the type 1 BB/Wor-rat, C-peptide replacement corrects metabolic abnormalities ameliorating the acute nerve conduction defect. It corrects abnormalities of neurotrophic factors and the expression of neuroskeletal proteins with improvements of axonal size and function. C-peptide corrects the expression of nodal adhesive molecules with prevention and repair of the functionally significant nodal degeneration. Cognitive dysfunction is a recognized complication of type 1 diabetes, and is associated with impaired neurotrophic support and apoptotic neuronal loss. C-peptide prevents hippocampal apoptosis and cognitive deficits. It is therefore clear that substitution of C-peptide in type 1 diabetes has a multitude of effects on DPN and cognitive dysfunction. Here the effects of C-peptide replenishment will be extensively described as they pertain to DPN and diabetic encephalopathy, underpinning its beneficial effects on neurological complications in type 1 diabetes.

Characterization of active phenolic components in the ethanolic extract of Ananas comosus L. leaves using high-performance liquid chromatography with diode array detection and tandem mass spectrometry.

HPLC-DAD-MS was utilized to investigate the phytochemical constituents in ethanolic extract of Ananas comosus L. leaves (EEACL) responsible for antidiabetic, antihyperlipidemic and antioxidative effects. Eight phenylpropane diglycerides, together with two hydroxycinnamic acids, three hydroxycinnamoyl quinic acids, four phenylpropane monoglycerides, three flavones and six phenylpropanoid glycosides were detected, and their proposed structures were elucidated based on HPLC retention time, UV and MS profiles. Meanwhile, a new HPLC-DAD-MS method was established for the identification and characterization of phenylpropane diglycerides in natural plants.

Alzheimer-like changes in rat models of spontaneous diabetes.

OBJECTIVE: To examine whether changes characteristic of Alzheimer's disease occur in two rat models with spontaneous onset of type 1 and type 2 diabetes. RESEARCH DESIGN AND METHODS: The frontal cortices of 8-month-diabetic rats were examined with respect to neuronal densities, neurite degeneration, expression, and/or immunolocalization of amyloid precursor protein (APP), beta-secretase, beta-amyloid, COOH-terminal fragment (CTF), insulin receptor, IGF-1 receptor, glycogen synthase kinase 3-beta (GSK-3beta), protein kinase B (Akt), phosphorylated tau (phospho-tau), synaptophysin, and phosphorylated neurofilaments (SMI-31). RESULTS: Neuronal loss occurred in both models, significantly more so in type 2 diabetic BBZDR/Wor rats compared with type 1 diabetic BB/Wor rats and was associated with a ninefold increase of dystrophic neurites. APP, beta-secretase, beta-amyloid, and CTF were significantly increased in type 2 diabetic rats, as was phospho-tau. The insulin receptor expression was decreased in type 1 diabetes, whereas IGF-1 receptor was decreased in both models, as were Akt and GSK-3beta expression. CONCLUSIONS: The data show that beta-amyloid and phospho-tau accumulation occur in experimental diabetes and that this is associated with neurite degeneration and neuronal loss. The changes were more severe in the type 2 diabetic model and appear to be associated with insulin resistance and possibly hypercholesterolemia. The two models will provide useful tools to unravel further mechanistic associations between diabetes and Alzheimer's disease.

[Study on HPLC fingerprint of processed Radix Angelicae Dahuricae].

OBJECTIVE: To establish HPLC fingerprint analysis for the quality control of processed Radix Angelicae Dahuricae. METHODS: HPLC fingerprint analysis of processed Radix Angelicae Dahuricae was developed Agilent C18 column (250 mm x 4.6 mm, 5 microm) was used, with mixture of acetonitrile and 5% phosphorous acid mobile phase in a gradient mode. The flow rate was 1.0 mL/min. The wavelength of measurement was 254 nm. Fifteen batches of processed Radix Angelicae Dahuricae were determined. RESULTS: The methodological evaluation showed that the method had a good repeatability. CONCLUSION: The method can be used to identify and evaluate the quality of Radix Angelicae Dahuricae conveniently.

Diabetes and Alzheimer's disease - is there a connection?

It has been known for some time that diabetes may be associated with impaired cognitive function. During the last decade, epidemiological data have emerged suggesting a linkage between diabetes, particularly type 2 diabetes, and Alzheimer's disease (AD). There is evidence to suggest that impaired activities of neurotrophic factors such as insulin, IGF-1 and NGF, which occur in both diabetes and AD, may provide a mechanistic link between the two disorders. An additional probable factor that has been less evaluated to date is hypercholesterolemia, a common accompaniment to type 2 diabetes. Increased cholesterol availability is believed to play a crucial role in the abnormal metabolism of amyloid precursor protein leading to accumulation of amyloid-beta. Impaired insulin signaling in particular appears to be involved in hyperphosphorylation of the tau protein, which constitutes neurofibrillary tangles in AD. The linkage between abnormal amyloid metabolism and phosphor-tau is likely to be provided by the activation of caspases both by increased amyloid-beta and by impaired insulin signaling. Although the details of many of these components still await evaluation, it appears clear that commonalities exist in the underlying pathogenesis of diabetes and Alzheimer's disease. In this review we provide a brief update on linkages between these two diverse but common disorders.

The effect of C-peptide on cognitive dysfunction and hippocampal apoptosis in type 1 diabetic rats.

Primary diabetic encephalopathy is a recently recognized late complication of diabetes resulting in a progressive decline in cognitive faculties. In the spontaneously type 1 diabetic BB/Wor rat, we recently demonstrated that cognitive impairment was associated with hippocampal apoptotic neuronal loss. Here, we demonstrate that replacement of proinsulin C-peptide in this insulinopenic model significantly prevented spatial learning and memory deficits and hippocampal neuronal loss. C-peptide replacement prevented oxidative stress-, endoplasmic reticulum-, nerve growth factor receptor p75-, and poly(ADP-ribose) polymerase-related apoptotic activities. It partially ameliorated apoptotic stresses mediated via impaired insulin and IGF activities. These findings were associated with the prevention of increased expression of Bax and active caspase 3 and the frequency of caspase 3-positive neurons. The results show that several partially interrelated apoptotic mechanisms are involved in primary encephalopathy and suggest that impaired insulinomimetic action by C-peptide plays a prominent role in cognitive dysfunction and hippocampal apoptosis in type 1 diabetes. Although these abnormalities were not fully prevented by C-peptide replacement, the findings suggest that this regime will substantially prevent cognitive decline in the type 1 diabetic population.

The role of impaired insulin/IGF action in primary diabetic encephalopathy.

We have previously shown that hippocampal neuronal apoptosis accompanied by impaired cognitive functions occurs in type 1 diabetic BB/Wor rats. To differentiate the contribution by insulin deficiency vs. that by hyperglycemia on neuronal apoptosis, we examined the activities of various apoptotic pathways in hippocampi from type 1 diabetic BB/Wor rats (hyperglycemic and insulinopenic) and type 2 diabetic BBZDR/Wor rats (hyperglycemic and hyperinsulinemic). DNA fragmentation was demonstrated by LM-PCR in type 1 diabetic BB/Wor rats, but was not detectable in duration- and hyperglycemia-matched type 2 BBZDR/Wor rats. Of various apoptotic pathways, Fas activations, 8-OHdG expression, and caspase-12 were demonstrated in type 1 diabetic BB/Wor rats only. In contrast, perturbations of the IGF and NGF systems and PARP activation were demonstrated in type 1 and to a lesser extent in type 2 diabetes. Expressions of Bax and active caspase-3 were significantly increased in type 1, but not in type 2, diabetic rats. These data suggest a lesser apoptogenic stress in type 2 vs. type 1 diabetes. These differences translated into a more profound neuronal loss in the hippocampus of type 1 rats. The results demonstrate that caspase-dependent apoptotic activities dominate in type 1 diabetes, whereas PARP-mediated caspase-independent apoptotic stress is present in both type 1 and type 2 diabetes. The findings suggest that insulin deficiency plays a compounding role to that of hyperglycemia in neuronal apoptosis underpinning primary diabetic encephalopathy.