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ABSTRACT: A series of novel N-linked diglycose derivatives 9 and 10 were conveniently and directly synthesized based on the key step of one-pot tandem Staudinger/aza-Wittig/reduction reaction from the azido sugar and sugar-derived aldehyde followed by deprotection. The biological activities against glycosidases (α-amylase, α-glucosidase, and β-glucosidase) and HIV-RT and antitumor activity of these compounds were preliminarily evaluated.
Carbohydrate research 02/2013; 372C:15-22. · 2.03 Impact Factor
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ABSTRACT: Objective: To detect the correlation between survivin and rheumatoid arthritis (RA) to determine the possible mechanism of RA and multidrug resistance in refractory rheumatoid arthritis (RRA). Methods: We collected 15 normal controls, 35 early untreated RA patients, 20 effectively treated RA patients and 25 RRA patients according to selection standard. The expression of survivin in the peripheral blood lymphocytes was detected by immunocytochemical method. Results: There was significant difference in the survivin expression in the peripheral blood lymphocytes between the early untreated and normal control group (χ=29.59, P<0.01). The survivin expression in the peripheral blood lymphocytes of effectively treated RA group slightly elevated, but had no significant difference with the normal control group (χ=1.591, P>0.05). The survivin expression in the peripheral blood lymphocytes of the RRA group was significantly stronger than in the effectively treated RA group (χ=24.35, P<0.01), and normal control group (χ=26.53, P<0.01), with no significant difference compared with early untreated group (χ=0.014,P>0.05). Conclusion: Survivin has an influential role in the occurrence and development of rheumatism arthritis. Survivin might be involved in refractory multidrug resistance of RA and be one of the multidrug resistance mechanism of RRA.
Zhong nan da xue xue bao. Yi xue ban = Journal of Central South University. Medical sciences 02/2013; 38(2):186-90.
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ABSTRACT: The fabrication and high-frequency ferromagnetic performances of nanocrystalline Fe70Co30-B soft magnetic films were investigated. It is revealed that the composition gradient sputtering method dramatically improves the high-frequency soft magnetic properties of the as-prepared films. This method gives rise to almost a linearly-increased distribution of compositions and residual stress. As a result, a very high ferromagnetic resonance frequency up to 6.7 GHz, high uniaxial magnetic anisotropic field up to 450 Oe, and low magnetic loss were obtained in as-deposited samples, which are particularly in favor of the integration between magnetic films and microwave components.
Journal of Nanoscience and Nanotechnology 02/2013; 13(2):1091-4. · 1.56 Impact Factor
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ABSTRACT: Nanocrystalline Co2MnSi Heusler alloy films were deposited on the PZN-PT substrates by a composition gradient sputtering method. It is revealed that this multiferroic heterostructure shows very strong magnetoelectric coupling, leading to continuously tunable microwave frequency characteristics by electric field. With the increase of electric field intensity from 0 to 6 kV/cm, the magnetic anisotropy field H(K) increases from 90 Oe to 182 Oe with an increment of 102%, corresponding to a ME coefficient of 15.3 Oe cm/kV; the ferromagnetic resonance frequency f(FMR) shifts from 3.38 to 4.82 GHz with an increment of deltaf(FMR) = 1440 MHz or deltaf(FMR)/f(FMR) = 43%; moreover, the damping constant alpha dramatically decreases from 0.035 to 0.018. These merits demonstrate that this nanocomposite multiferroic structure is promising in fabrication of tunable microwave components.
Journal of Nanoscience and Nanotechnology 02/2013; 13(2):1182-5. · 1.56 Impact Factor
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ABSTRACT: Cerebral ischemia, traumatic brain injury, intracerebral hemorrhage and other brain insults trigger neurogenesis in the subventricular zone and hippocampal subgranular zone, and newly formed blood vessels promote the migration of these new neuronal cells to damaged brain regions. The molecular steps involved in brain injury-induced angiogenesis and neurogenesis are unclear. Here we used a rat model of collagenase-induced intracerebral hemorrhage (ICH) to examine whether matrix metalloproteinase-9 (MMP-9), a zinc endopeptidase that regulates growth factor levels during recovery from brain injury, is involved in neurogenesis and angiogenesis following ICH. Induction of ICH led to significant increases in the levels of MMP-9, VEGF, and NGF, as well as in the numbers of BrdU- and DCX-positive cells, in the ipsilateral brain. Intracerebroventricular injection of MMP-9 siRNA reduced these ICH-induced increases. These findings suggest that MMP-9 may promote angiogenesis and neurogenesis during recovery from ICH.
Neuroscience 11/2012; · 3.38 Impact Factor
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ABSTRACT: BACKGROUND: Cerebral microbleeds (MBs), defined as haemorrhagic microvascular lesions or microangiopathy in the brain, have traditionally been considered clinically silent. Recent studies, however, suggest that MBs are associated with a decline in cognitive function. OBJECTIVE: To determine whether an association between MBs and cognitive function exists, we conducted a systematic review of the literature using the Cochrane Library, MEDLINE, EMBASE and the China National Knowledge Infrastructure database. We also searched the reference lists of relevant studies and review articles. RESULTS: A total of seven studies were included. Qualitative meta-analysis of two studies suggested that the presence of MBs was significantly associated with cognitive impairment, while quantitative meta-analysis revealed an association between MBs and cognitive dysfunction in two studies (OR 3.06, 95% CI 1.59 to 5.89) and implicated MBs as important in cognitive function decline in three other studies (standardised mean difference -1.06, 95% CI -2.10 to -0.02). MBs in the frontal or temporal region and the basal ganglia might also be related to cognitive dysfunction. CONCLUSIONS: These results suggest that rather than being clinically silent, cerebral MBs might be a factor inducing cognitive function decline.
Journal of neurology, neurosurgery, and psychiatry 11/2012; · 4.87 Impact Factor
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ABSTRACT: Background and Purpose: FTY720 (fingolimod) is a known sphingosine-1-phosphate (S1P) receptor agonist, which has been used in clinical trials for treating multiple sclerosis, renal transplantation, and decreasing reperfusion injury in heart, liver, and kidney. Most of these clinical trials have showed a positive effect. Especially, the trials of MS showed a reduction of relapse rate in FTY720 treated patients. Now, some animal experiments indicated that FTY720 could be a new compound available treatment for stroke patients by exerting neuroprotection via S1P1 mediated antiapoptotic mechanisms. Whether it could be effective in animals is unclear, so we conducted a systematic review to make it clear. Methods: We conducted a systematic review and meta-analysis of the efficacy of FTY720 in animal models of focal cerebral ischemia by electronic and manual searches of the literature. Data on study quality, FTY720 dose, time of administration, and outcome measured as infarct volume or functional deficit were extracted. Data from all studies were analyzed by means of a standardized mean difference meta-analysis. Results: Of the 19 identified studies, 9 were included. Among all the included studies, 178 animals were calculated for infarct size and 194 animals were assessed of neurological deficits. The methodological quality of the studies ranged from 2 to 10 according to a published 11-item quality scale. Of the 9 studies selected, only one reported a negative result of FTY720.The result indicated that FTY720 reduced the infarct volume (SMD = -1.31, 95%CI -1.99 to -0.63)and improve the functional outcome(SMD = -1.61,95% CI -2.17to -1.05). Conclusions: The data we included supporting FTY720 was a candidate drug for stroke, but which should be considered with caution. More good quality experimental studies should be performed to evaluate the safety of FTY720 in the future. Whether FTY720 is effective in aged animals which mimicked human with comorbidities, like diabetes and hypertension should also be diliberated.
The International journal of neuroscience 11/2012; · 0.86 Impact Factor
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ABSTRACT: Neural stem cells, which reside mainly in the subventricular and subgranular zones of the hippocampus, can regenerate new neuroblasts after various brain insults. Aided by vascular remodeling, these new neuroblasts migrate long distances to injured brain regions. Studies have suggested that high-mobility group box1 (HMGB1), a nonhistone nuclear DNA-binding protein, may stimulate such remodeling in the late phase of some types of brain injury, but it is unclear whether this is true for intracerebral hemorrhage (ICH). Here we used a rat model of collagenase-induced ICH to determine whether HMGB1 can promote neurogenesis and angiogenesis in the late phase of injury. Daily administration of ethyl pyruvate, which inhibited HMGB1 expression, reduced recovery of neurological function, decreased VEGF and NGF levels in the ipsilateral striatum, and decreased the numbers of BrdU- and DCX-positive cells around the hematoma. These findings suggest that HMGB1 may promote angiogenesis and neurogenesis in the late phase of ICH.
Neuroscience 11/2012; · 3.38 Impact Factor
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ABSTRACT: Reduced blood hemoglobin levels may impair oxygen delivery to the brain and hinder neurological improvement. We prospectively registered consecutively hospitalized Chinese patients with acute ischemic stroke within 24hours of symptom onset to investigate whether anemia on admission influences case fatality and functional outcome of acute ischemic stroke at 12months. Anemia was defined as a blood hemoglobin level of < 120g/L for women, and < 130g/L for men. We also performed a meta-analysis of the current cohort and previously published studies. We included 1176 patients, of whom 351 patients (29.8%) had anemia. Age (odds ratio [OR]=1.02, 95% confidence interval [CI]: 1.01-1.03), history of hemorrhagic stroke (OR=3.34, 95% CI: 1.17-9.56), alcohol consumption (OR=0.59, 95% CI: 0.38-0.92), and estimated glomerular filtration rate < 60mL/minute per 1.73m(2) (OR=1.34, 95% CI: 1.00-1.80) were the independent predictors of anemia. After adjustment for potential confounders, anemia on admission was shown to be an independent predictor of death at discharge and at 12months (OR=1.66, 95% CI, 1.08-2.56; OR=1.56, 95% CI, 1.05-2.31). A meta-analysis of six included studies involving 3810 participants confirmed that anemia on admission was an independent predictor of death at the end of follow-up (OR=1.67, 95% CI, 1.25-2.08). Further studies are required to confirm these findings.
Journal of Clinical Neuroscience 10/2012; · 1.25 Impact Factor
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ABSTRACT: High-mobility Group Box1 (HMGB1) protein is massively released into the cytoplasm induces inflammation following various insults such as sepsis, acute cerebral ischemia, and pancreatitis. However, whether HMGB1 can act as an early proinflammatory cytokine to promote inflammation after intracerebral hemorrhage (ICH) is unclear. We explored this question using a rat model of collagenase-induced ICH. We found that HMGB1 was released into the cytoplasm soon after ICH. Administration of ethyl pyruvate decreased the level of HMGB1 and microglia around the hematoma. Ethyl pyruvate also ameliorated ICH-induced neuronal apoptosis, cerebral edema, and neurological impairment. These findings suggest that HMGB1 may act as an early proinflammatory cytokine within the neurovascular unit to mediate inflammation during the acute phase of ICH.
Neuroscience 10/2012; · 3.38 Impact Factor
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ABSTRACT: Admission hyperglycaemia is very common in acute ischaemic stroke (IS) patients and is associated with worse outcome in non-lacunar infarction, but its association with lacunar infarction remains controversial. We investigated the association between hyperglycaemia and clinical outcome in patients with acute lacunar stroke in a hospitalised Chinese population. Consecutive patients with acute IS were enrolled and classified into lacunar and non-lacunar stroke groups based on clinical criteria according to the Oxfordshire Community Stroke Project (OCSP) and findings on brain computed tomography (CT) or magnetic resonance imaging (MRI) scan. Hyperglycaemia was defined as blood glucose > 6.1 mmol/L. Univariate and multivariate analyses were used to examine the association between hyperglycaemia and outcomes in diabetic and non-diabetic groups. The main outcome measure was a poor outcome [defined as modified Rankin Scale (mRS) score ≥ 3] at 12 months after stroke. Of the 2020 acute ISs, 689 (34.1%) were acute lacunar strokes, of which 159 (23%) were diabetic and the other 530 (77%) were non-diabetic. In non-lacunar stroke, admission hyperglycaemia was independently associated with increased risk of poor outcome at 1 year (odds ratio (OR) = 1.782; 95% confidence interval (CI) = 1.340-2.370, p = 0.0005). In lacunar stroke, hyperglycaemia was not associated with functional outcome (OR = 1.337; 95% CI = 0.939-1.093, p = 0.086) irrespective of the diabetic status.
Diabetes & Vascular Disease Research 10/2012; · 2.12 Impact Factor
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ABSTRACT: Rheumatic heart disease (RHD) is an important risk factor for ischemic stroke in developing countries. Observational data on its characteristics and influence on outcome or recurrence of ischemic stroke are scarce. We aimed to investigate proportions, characteristics, functional outcome, and recurrence of acute ischemic stroke patients with RHD in a hospitalized Chinese population.
We prospectively enrolled consecutive patients with acute ischemic stroke who were admitted within 1 month of stroke onset from January 2003 to February 2007, into the analysis. Clinical characteristics such as age, gender, risk factors, and National Institutes of Health Stroke Scale on admission were investigated. Basic characteristics, functional outcomes, and recurrence were compared between RHD group and nonRHD group.
Of the 1638 cases included, RHD was present in 130 patients (7.9%). RHD patients, compared with those without RHD, were younger, more frequently female, and more often had experienced atrial fibrillation and higher National Institutes of Health Stroke Scale score on admission (all P<0.006). After adjustment for age, sex, and National Institutes of Health Stroke Scale on admission, the death risk in patients with RHD was 2.0-fold higher at 3 months, 6 months, and 1 year compared with patients without RHD (all P<0.013). Compared with patients without RHD, those with RHD showed a significantly higher cumulative recurrence rate (13.6% vs 6.0%; P=0.001, log rank test) by 1-year cumulative recurrent curves.
Stroke attributable to RHD is still common in the Chinese population. RHD was associated with 2-fold increased risk of death and 1-fold increased risk of recurrence in stroke patients.
Stroke 09/2012; 43(11):2853-7. · 5.73 Impact Factor
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ABSTRACT: Background: Randomized controlled trials (RCTs) are the most important evidence to guide clinical practice in the treatment of acute stroke. This study aims to evaluate the changes of quantity and methodological quality of acute stroke RCTs in Mainland China published in recent 15 years. Method: We included un-confounded RCTs on acute stroke from eight databases published in Chinese or English from 1996 to 2010. General characteristics, design methodology, and outcome measures of studies were assessed. Results: Totally, 9061 RCTs were identified. The number of acute stroke RCTs had increased by years, the total of trials published in 2010 was 20 times of that published in 1996. Three thousand four hundred eighty-eight trials (38.5%) used western drugs in the treatment, 3026 (33.4%) trials used traditional Chinese medicine (TCM), and 1933 (22.0%) trials used physical therapy. Ischemic stroke was the most common research subject among all trials (65.1%, 5,989). There were 541 (6.0%) RCTs using adequate randomization methods, 34 (0.4%) RCTs using adequate allocation concealment, and 195 (2.2%) using adequate blinding methods. Thirty-three (0.4%) RCTs adopted both adequate randomization methods and allocation concealment. Only 23 (0.3%) trials used all three methods of adequate randomization methods, allocation concealment, and blinding. During the 15 years, only the number of trials using adequate randomized methods and reporting adverse events had significantly increased (both P < 0.001). As for these RCTs, only the number of trials using adequate blinding method in pharmaceutical intervention was statistical differences compared with that of nondrug intervention trials (P = 0.043). Outcomes were assessed blindly in 72 trials. Death was reported by 14.2% of trials, impairment by 85.1%, disability by 22.5%, and handicap or quality of life by 0.4%. 99.7% trials reported positive results. Larger trials were more likely to use adequate randomized methods, allocation concealment and blinding methods, as well as to measure disability. Only 14 large-sample high-quality RCTs were found. Conclusion: During 15 years, the number of acute stroke RCTs has increased dramatically, but the quality of trials improves slowly. Most acute stroke trials used inadequate outcome measures in terms of their content, reliability, validity, blinding assessment.
Journal of Evidence-Based Medicine 08/2012; 5(3):174-182.
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Wen-Dan Tao, Ming Liu,
Marc Fisher,
De-Ren Wang,
Jie Li,
Karen L Furie,
Zi-Long Hao,
Sen Lin,
Can-Fei Zhang,
Quan-Tao Zeng,
Bo Wu
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ABSTRACT: Distinguishing between symptoms of posterior circulation infarction (PCI) and anterior circulation infarction (ACI) can be challenging. This study evaluated the frequency of symptoms/signs in the 2 vascular territories to determine the diagnostic value of particular symptoms/signs for PCI.
Neurological deficits were reviewed and compared from 1174 consecutive patients with a diagnosis of PCI or ACI confirmed by magnetic resonance imaging in the Chengdu Stroke Registry. The diagnostic value of specific symptoms/signs for PCI was determined by measuring their sensitivity, specificity, positive predictive value (PPV), and the OR.
Homolateral hemiplegia (PCI, 53.6% versus ACI, 74.9%; P<0.001), central facial/lingual palsy (PCI, 40.7% versus ACI, 62.2%; P<0.001), and hemisensory deficits (PCI, 36.4% versus ACI, 34.2%; P=0.479) were the 3 most common symptoms/signs in PCI and ACI. The signs with the highest predictive values favoring a diagnosis of PCI were Horner's syndrome (4.0% versus 0%; P<0.001; PPV=100.0%; OR=4.00), crossed sensory deficits (3.0% versus 0%; P<0.001; PPV=100.0%; OR=3.98), quadrantanopia (1.3% versus 0%; P<0.001; PPV=100.0%; OR=3.93), oculomotor nerve palsy (4.0% versus 0%; P<0.001; PPV=100.0%; OR=4.00), and crossed motor deficits (4.0% versus 0.1%; P<0.001; PPV=92.3%; OR=36.04); however, all had a very low sensitivity, ranging from 1.3% to 4.0%.
This study indicates that the symptoms/signs considered typical of PCI occur far less often than was expected. Inaccurate localization would occur commonly if clinicians relied on the clinical neurological deficits alone to differentiate PCI from ACI. Neuroimaging is vital to ensure accurate localization of cerebral infarction.
Stroke 06/2012; 43(8):2060-5. · 5.73 Impact Factor
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ABSTRACT: With recent progress in material science, resistive random access memory (RRAM) devices have attracted interest for nonvolatile,
low-power, nondestructive readout, and high-density memories. Relevant performance parameters of RRAM devices include operating
voltage, operation speed, resistance ratio, endurance, retention time, device yield, and multilevel storage. Numerous resistive-switching
mechanisms, such as conductive filament, space-charge-limited conduction, trap charging and discharging, Schottky Emission,
and Pool-Frenkel emission, have been proposed to explain the resistive switching of RRAM devices. In addition to a discussion
of these mechanisms, the effects of electrode materials, doped oxide materials, and different configuration devices on the
resistive-switching characteristics in nonvolatile memory applications, are reviewed. Finally, suggestions for future research,
as well as the challenges awaiting RRAM devices, are given.
Keywordsresistive random access memory–resistive switching–performance parameters
Chinese Science Bulletin 05/2012; 56(28):3072-3078. · 1.32 Impact Factor
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Sen Zhang,
Qi Liu,
Wei Wang,
Hangbing Lv,
Qingyun Zuo,
Yan Wang,
Yingtao Li,
Wentai Lian,
Shibing Long,
Qin Wang, Ming Liu
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ABSTRACT: Resistive switching memory is a very promising technology for emerging nonvolatile memory applications. Generally, the switching
behavior is triggered by a sweep or pulse voltage. In this paper, a charged capacitor is proposed to be used as the external
electrical source to program a resistive switching element. From theoretical analyses based on a set behavior model, the capacitor
approach can program the device efficiently. Compared with sweep or pulse mode, capacitor driving method can greatly reduce
over-programming after the set event, and thus improve the resistance uniformity. The experimental results performed on Cu/ZrO2:Cu/Pt device support this conclusion quite well. The proposed methodology has great value for achieving a reliable resistive
switching, which is important for high density or embedded application such as memory, FPGA, DSP, and even neuromorphic systems.
Applied Physics A 04/2012; 102(4):1003-1007. · 1.63 Impact Factor
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ABSTRACT: In order to obtain both high electromigration (EM) reliability and fine-dimensional control in high-frequency surface acoustic
wave (SAW) devices, 4-layered Ti/Al-Mo/Ti/Al-Mo electrode films were investigated on 128° Y-X LiNbO3 substrates by sputtering deposition. The results indicated that the 4-layered films had an improved EM reliability compared
to conventional Al-0.5wt.%Cu films. Their lifetime is approximately three times longer than that of the Al-0.5wt.%Cu films
tested at a current density of 5 × 107 A/cm2 and a temperature of 200°C. Moreover, the 4-layered films were easily etched in reactive ion etching and fine-dimensional
control was realized during the pattern replication for high-frequency SAW devices. For the 4-layered films, an optimum Mo
quantity and sputtering parameters were very significant for high EM reliability.
Rare Metals 04/2012; 28(6):554-558. · 0.59 Impact Factor
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ABSTRACT: Low voltage operating organic devices and circuits have been realized using atomic layer deposition deposited aluminum oxide
thin film as dielectric layer. The dielectric film has per unit area capacitance of 165 nF/cm2 and leakage current of 1 nA/cm2 at 1 MV/cm. The devices and circuits use the small-molecule hydrocarbon pentacene as the active semiconductor material. Transistors,
inverters, and ring oscillators with operating voltage lower than 5 V were obtained. The mobility of organic field-effect
transistors was extracted to be 0.16 cm2/Vs in saturation range, the threshold voltage is 0.3 V, and the on/off current ratio is larger than 105. The gain of inverters is estimated to be 12 at −5 V supply voltage, and the propagation delay is 0.25 ms per stage in 5-stage
ring oscillators.
KeywordsOFET–low voltage–atomic layer deposition–Al2O3 thin film–high-k dielectric
Science China Technological Sciences 04/2012; 54(1):95-98. · 0.75 Impact Factor
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ABSTRACT: Reports investigating the association between the genetic polymorphism of glutathione S-transferase T1 (GSTT1) and the risk of rheumatoid arthritis (RA) have revealed conflicting results. To clarify the effect of GSTT1 polymorphism on the risk of developing RA, we carried out a meta-analysis using published data.
Electronic searches were conducted to select studies. Reports were included if they were observational studies investigating the link between GSTT1 genotype and the risk of RA. The principal outcome measure was the odds ratio (OR) with 95% confidence interval (CI) for the risk of RA with GSTT1 null genotype.
We identified 7 eligible studies including 2652 cases and 4117 controls. The combined results showed that there was not a statistically significant link between GSTT1 null genotype and RA. However, we observed an increased risk in heavy smokers (cigarette consumption >10 pack-years) with GSTT1 null polymorphism compared with never or light smokers (cigarette consumption ≤10 pack-years) with GSTT1 present. Moreover, compared to GSTT1 positive polymorphism with seronegative results, there was an increased risk in GSTT1 null polymorphism with seropositive results.
The results from this meta-analysis suggested that GSTT1 null genotype is not association with an increased susceptibility to RA. However, GSTT1 null polymorphism may increase the risk of RA in relation to heavy smokers or seropositive results. Whether GSTT1 polymorphism may act in synergy with other genes or environmental factors remains to be studied more in depth.
Clinical and experimental rheumatology 04/2012; 30(5):741-7. · 2.15 Impact Factor
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ABSTRACT: Vibrio parahaemolyticus is a major causative agent of gastroenteritis, particularly in areas with high seafood consumptions, and it has recently become pandemic due to the emergence of the serotype O3:K6 (12). Major virulence factors, Tdh and Trh, have been implicated in V. parahaemolyticus that caused most of the clinical infections (17).
Antimicrobial Agents and Chemotherapy 04/2012; 56(7):4026-8. · 4.84 Impact Factor
