CNTN1 Aggravates Neuroinflammation and Triggers Cognitive Deficits in Male Mice by Boosting Crosstalk between Microglia and Astrocytes.

A wealth of knowledge regarding glial cell-mediated neuroinflammation, which contributes to cognitive deficits in Alzheimer's disease (AD) has emerged in recent years. Contactin 1(CNTN1), a member of the cell adhesion molecule and immunoglobulin supergene family, is centrally involved in axonal growth regulation and is also a key player in inflammation-associated disorders. However, whether CNTN1 plays a role in inflammation-related cognitive deficits and how this process is triggered and orchestrated remain to be fully elucidated. In this study, we examined postmortem brains with AD. CNTN1 immunoreactivity was markedly increased, particularly in the CA3 subregion, as compared with non-AD brains. Furthermore, by applying an adeno-associated virus-based approach to overexpress CNTN1 directly via stereotactic injection in mice, we demonstrated that hippocampal CNTN1 overexpression triggered cognitive deficits detected by novel object-recognition, novel place-recognition and social cognition tests. The mechanisms underlying these cognitive deficits could be attributed to hippocampal microglia and astrocyte activation, which led to aberrant expression of excitatory amino acid transporters (EAAT)1/EAAT2. This resulted in long-term potentiation (LTP) impairment that could be reversed by minocyline, an antibiotic and the best-known inhibitor of microglial activation. Taken together, our results identified Cntn1 as a susceptibility factor involved in regulating cognitive deficits via functional actions in the hippocampus. This factor correlated with microglial activation and triggered astrocyte activation with abnormal EAAT1/EAAT2 expression and LTP impairment. Overall, these findings may significantly advance our understanding of the pathophysiological mechanisms underlying the risk of neuroinflammation related cognitive deficits.

Soybean GmSAUL1, a Bona Fide U-Box E3 Ligase, Negatively Regulates Immunity Likely through Repressing the Activation of GmMPK3.

E3 ubiquitin ligases play important roles in plant immunity, but their role in soybean has not been investigated previously. Here, we used Bean pod mottle virus (BPMV)-mediated virus-induced gene silencing (VIGS) to investigate the function of GmSAUL1 (Senescence-Associated E3 Ubiquitin Ligase 1) homologs in soybean. When two closely related SAUL1 homologs were silenced simultaneously, the soybean plants displayed autoimmune phenotypes, which were significantly alleviated by high temperature, suggesting that GmSAUL1a/1b might be guarded by an R protein. Interestingly, silencing GmSAUL1a/1b resulted in the decreased activation of GmMPK6, but increased activation of GmMPK3 in response to flg22, suggesting that the activation of GmMPK3 is most likely responsible for the activated immunity observed in the GmSAUL1a/1b-silenced plants. Furthermore, we provided evidence that GmSAUL1a is a bona fide E3 ligase. Collectively, our results indicated that GmSAUL1 plays a negative role in regulating cell death and immunity in soybean.

[Interaction of Chinese and western medicines in treatment of cardiovascular diseases].

Cardiovascular diseases are a global public health problem, and the combination of Chinese and western medicine tends to be a major solution in China. However, the complex components in traditional Chinese medicine may interact with the therapeutic western medicines for the diseases, which will lead to the herb-drug interaction(HDI). The information on the interaction can serve as a reference for the rational combination of the Chinese and western medicines in the clinical treatment of cardiovascular diseases and help avoid the occurrence of clinical safety events. However, the research on the interaction of Chinese medicine is limited as compared with that on western medicine, and no systematic review on HDI in the treatment of cardiovascular diseases is available. Therefore, this study first introduced the mechanism of HDI, then summarized the research on HDI for the commonly used drugs for cardiovascular diseases, analyzed the problems in the available studies, and put forward suggestions on the application, regulation, and research. This study aims to highlight HDI in clinical drug use and provide a reference for rational use of combination of Chinese and western medicines in the treatment of cardiovascular diseases.

[Effects of sleep deprivation induced blood stasis syndrome on platelet activation in rats].

Blood stasis syndrome is the pre-state of thrombotic disease. The model of blood stasis syndrome in rats was induced by sleep deprivation to study on effects of blood stasis syndrome on platelet activation. The weight, the color of tongue and hemorheology for the blood stasis syndrome of Chinese medicine were measured after modeling. The release of platelet granules and platelet activation factors in plasma were detected by ELISA kit related indicators to provide experimental basis for platelet function evaluation and related drug effects in syndrome research. The results showed that the weight of the model group rats was significantly lower than that of the normal group (P<0.01). The tongue showed a dark purple blood stasis pattern, and the R, G and B values of the tongue surface in model group were significantly lower than those of the normal group (P<0.01). The hemorheological parameters including high shear, middle shear and low shear viscosity in whole blood were significantly higher than those in the normal group (P<0.01). But plasma viscosity did not change significantly. The release levels of platelet α particles (GMP-140, ß-TG, PF4) and dense particles (ADP, 5-HT) were significantly higher than those in the normal group (P<0.01). The levels of TXB2 and 6-keto-PGF1α in plasma were significantly higher than those in the normal group (P<0.01). The ratios of TXB2 and 6-keto-PGF2α were also significantly higher than those in the normal group (P<0.01). The levels of PAF in plasma in model group were significantly higher than those in the normal group (P<0.01). It was concluded that platelet functions could be changed induced by sleep deprivationin rats with blood stasis syndrome, and there might be inflammation and endothelial cell dysfunction.

[Characterization and pathophysiological changes of cerebral infarction rat model with qi-deficiency and blood-stasis Syndrome].

This study aimed to observe the general state and changes in pathophysiological indexes of multiple cerebral infarction rat model with Qi-deficienty and Blood-stasis syndrome. Rats were randomly divided into 4 groups(with 30 in each group): the normal group, the sham group, the model group and the Yiqi Huoxue recipe group. Rats in the model group and Yiqi Huoxue group were provided with interruptable sleep deprivation for 7 days before the multiple cerebral infarction operation, and followed by another 4 weeks of sleep deprivation; rats in the Yiqi Huoxue group were intragastrically administrated with drug at a dose of 26 g·kg⁻¹, once a day for 4 weeks. The general state was observed, and the pathophysiological indexes were measured at 48 h, 2 weeks and 4 weeks after administration. The results showed that rats in the normal group and the sham group represented a good general state and behaviors, with a normal morphological structure of brain tissues; rats in the model group featured yellow fur, depression, accidie, loose stools and movement disorder, with obvious brain histomorphological damage, which became aggravated with the increase of modeling time; rats in the Yiqi Huoxue group showed release in the general state and above indexes. Compared with the sham group at three time points, rats in the model group showed decrease in body weight, exhaustive swimming time and RGB value of tongue surface image, and increase in whole blood viscosity of the shear rate under 5, 60 and 150 S⁻¹, reduction in cerebral cortex Na⁺-K⁺-ATPase, Ca²âº-ATPase activity and contents of 5-HT, rise in TXB2 levels and decline in 6-keto-PGF1a in serum(P<0.05, P<0.01). Compared with the model group, rats in the Yiqi Huoxue group showed alleviations in the above indexes at 2 w and 4 w(P<0.05, P<0.01). The results showed that the characterization and pathophysiological indexes in the multiple cerebral infarction rat model with Qi-deficiency and blood-stasis syndrome were deteriorated; Yiqi Huoxue recipe could significantly alliviate the abnormal conditions, which suggested of the model was stable and reliable and the pathophysiologic evolutionary mechanism might be related to energy metabolism dysfunction, vasoactive substance abnormality and changes in neurotransmitters.

Brucella induces unfolded protein response and inflammatory response via GntR in alveolar macrophages.

Brucella is an intracellular bacterium that causes the zoonosis brucellosis worldwide. Alveolar macrophages (AM) constitute the main cell target of inhaled Brucella. Brucella thwarts immune surveillance and evokes endoplasmic reticulum (ER) stress to replicate in macrophages via virulence factors. The GntR regulators family was concentrated as an important virulence factor in controlling virulence and intracellular survival of Brucella. However, the detailed underlying mechanism for the host-pathogen interaction is poorly understood. In this study the BSS2_II0438 mutant (ΔGntR) was constructed. The type IV secretion system (T4SS) virulence factor genes (VirB2, VirB6, and VirB8) were down-expression in ΔGntR. ΔGntR could infect and proliferate to high titers in GAMs without a significant difference compared with the parental strain. ΔGntR infection increased the expression of ER stress marker genes GRP78, ATF6, and PERK in the early stages of its intracellular cycle but decreased the expression of these genes in the late stages. ΔGntR increased greatly the number of Brucella CFUs in the inactive ER stress state in GAMs. Meanwhile, ΔGntR infection increased the levels of IFN-γ, IL-1ß, and TNF-α, indicating ΔGntR could induce the secretion of inflammatory but not anti-inflammatory cytokines IL-10. Taken together, our results clarified the role of the GntR in B. suis. S2 virulence expression and elucidated that GntR is potentially involved in the signaling pathway of the Brucella-induced UPR and inflammatory response in GAMs.

Allicin improves carotid artery intima-media thickness in coronary artery disease patients with hyperhomocysteinemia.

Homocysteine (Hcy) is an important and independent risk factor for atherosclerotic diseases, such as coronary artery disease and ischemic cerebrovascular disease. Increased carotid artery intima-media thickness (IMT) is a non-invasive marker of systemic atherosclerosis. Allicin treatment may decrease serum Hcy levels and improve impaired endothelial function in rats with hyperhomocysteinemia (HHcy). The present study hypothesized that allicin has an anti-atherosclerotic effect in coronary heart disease and tested the effects of allicin treatment on carotid artery IMT and plasma Hcy levels in coronary heart disease patients with HHcy. Sixty-two coronary heart disease patients with HHcy were randomly divided into an allicin group and a control group. All patients underwent diagnostic assessment, plasma Hcy assay, blood lipid measurement and B-mode ultrasound of the carotid artery prior to and after treatment. Plasma Hcy levels were determined by high-performance liquid chromatography and fluorescence detection. Carotid artery IMT was calculated using an automated algorithm based on a validated edge-detection technique. After 12 weeks, significant decreases in carotid artery IMT, plasma Hcy levels, total cholesterol and triglycerides were observed in the allicin group (all P<0.05), and the decreases in the allicin group were significantly greater than those in the control group (all P<0.01). These findings suggested that reducing plasma Hcy levels may be useful for preventing the generation and development of atherosclerosis in patients with coronary heart disease. Allicin was able to decrease Hcy levels, total cholesterol and triglycerides as well as carotid artery IMT.

Prevalence and Predictors of Hypertension in the Labor Force Population in China: Results from a Cross-sectional Survey in Xinjiang Uygur Autonomous Region.

The objective of this study was to examine the prevalence of hypertension and identify its contributory factors in the labor force population in Karamay. A total of 2819 adults (55.9% male adults) were interviewed and examined. The overall crude prevalence of hypertension was 32.4%. Among 914 hypertensive patients, 34.8% were aware of their diagnosis, 22.1% received treatment, and 5.6% achieved blood pressure control. Hypertension was significantly correlated with age, overweight/obesity, central obesity, diabetes, and dyslipidemia in both men and women. In addition, less education, alcohol consumption, and less walking were risk factors for men. Effective hypertension prevention and control programs are urgently needed to decrease the burden of hypertension in this region.

[Determination of aflatoxin B1, B2, G1, G2 in Ben Lamge granules by HPLC-FLD after multi-pretreatment clean-up].

To establish a multi-pretreatment method for the determination of aflatoxin B1, B2, G1, G2 in Chinese patent medicines, aflatoxins were analyzed by high performance liquid chromatography-fluorescence detector with post-column derivatization, after the multi-pretreatment of samples. The results showed that after the samples extracted with MeOH-H2O, dehydrated by anhydrous magnesium sulphate and sodium chloride, and finally purified by neutral alumina, the impurity interference of different sources in Chinese patent medicines matrix can be effectively removed, and the main peak can be nicely separated from the impurity peak. The detection limits were 0.25, 0.25, 0.50, 0.25 µg x L(-1) for AFB1, AFB2, AFG1, AFG2, respectively. The quantification limits were 1.00, 0.50, 1.00, 0.50 µg x L(-1), respectively. Aflatoxin B1, G1 showed a good linear relationship at a range of 1.0-50 µg x L(-1), aflatoxin B2, G2 at a range of 0.5-12.5 µg x L(-1) (R2 > 0.99). The average recovery was 80.40% - 108.6%. The present method is simple, reproducible with the reasonable recoveries and can be applied for the determination of aflatoxins in Chinese patent medicines.

[Clinical analysis of syndrome-relative biological indices in acute lacuna encephalon infarction patients of upper hyperactivity of Gan Yang syndrome].

OBJECTIVE: To analyze and summarize changes of syndrome-related biological indices in acute lacuna encephalon infarction patients of upper hyperactivity of Gan yang syndrome (UHGYS), thus providing objective evidence for syndrome typing and disease identification. METHODS: Recruited were 50 patients at Department of Encephalopathy, Xiyuan Hospital, China Academy of Chinese Medical Sciences, who were in line with diagnostic criteria of UHGYS as the experimental group in this study. Another 40 healthy volunteers were recruited as the control group from May 2010 to July 2012. Blood routines (including WBC, RBC, Hb, NEUT%, and LY%), hepatic and renal functions tests (including ALT, AST, TBIL, TP, ALB, Cr, and BUN) were performed by automatic whole blood analyzer and colorimetric technique. The levels of fasting blood glucose, HbAlc, blood lipids (including TC, TG, HDL-C, LDL-C, and VLDL-C), and coagulation functions (including AT-III, PT, PTA, INR, TT, APTT, and FBG, reaction time), renin, angiotensin II, hs-CRP, and Hcy were also measured. The thyroid functions (including FT3, FT4, T3, T4, and TSH) were detected by electrochemiluminescence immunoassay. The levels of tumor necrosis factor alpha (TNF-alpha), IL-6 and IL-1 in serum were measured by ELISA and radioimmunoassay respectively. RESULTS: Compared with the control group, RBC, LY%, ALT, TP, ALB, HDL-C, AT-III activities, contents of PTA and FT4 obviously decreased, TBIL, BUN, Glu, HbAlc, TSH, hs-CRP, renin, Ang II, TNF-alpha, IL-1 and IL-6 significantly increased in the experimental group (P < 0.05, P < 0.01). CONCLUSION: The pathological process of acute lacuna encephalon infarction patients of UHGYS was closely correlated with thyroid functions, the renin-angiotensin-aldosterone system, the extrinsic and intrinsic coagulation systems, as well as inflammation reaction.

[Effect of formula of removing both phlegm and blood stasis on inflammatory reaction in Chinese mini-swine with coronary atherosclerosis].

OBJECTIVE: To observe the effect of formula of removing both phlegm and blood stasis (TYTZ) in inhibiting the inflammatory reaction in Chinese mini-swine with coronary atherosclerosis. METHOD: Totally 36 Chinese mini-swine were randomly divided to six groups: the normal control group, the model group, the Shujiangzhi group and TYTZ groups with does of 2.0, 1.0 and 0.5 g x kg(-1), and six each in every group. Except for the normal control group, all of other groups were fed with high-fat diet for 2 weeks. Interventional balloons are adopted to injure their left anterior descending artery endothelium. After the operation, they were fed with high-fat diet for 8 weeks to prepare the coronary atherosclerosis model. In the 8th week after the operation and administration, the intravascular ultrasound was adopted to observe the coronary artery plaque burden of each group and the pathological morphology of coronary artery. Such inflammatory factors as high-sensitivity C-reactive protein (hs-CRP), tumor necrosis factor (TNF)-alpha and interleukin (IL)-6 were detected by ELISA. The expression of NF-kappaB p65 nuclear translocation was observed by the immunohistochemical method. RESULT: Compared with the normal control group, the model group showed significant increase in the coronary artery plaque burden at the end of the experiment (P < 0.01), notably abnormal structural changes in atherosclerotic vascular tissues, luminal stenosis, a large number of foam cells and inflammatory cell infiltration, remarkable growth of hs-CRP, TNF-alpha and IL-6 levels (P < 0.01). The immunohistochemical staining also showed the significant increase in the NF-kappaB p65 nuclear translocation of coronary artery of Chinese mini-swine in the model group. Compared with the model group, TYTZ could significantly attenuate atherosclerotic plaque burden (P < 0.01), inhibit the coronary luminal stenosis, reduce inflammatory cell infiltration, decrease such inflammatory cell factors as hs-CRP, TNF-alpha and IL-6 in serum, and inhibit the NF-kappaB p65 nuclear translocation of coronary artery (P < 0.05 or P < 0.01). CONCLUSION: TYTZ can reduce the downstream inflammatory reaction by controlling NF-kappaB p65 nuclear translocation, so as to inhibit the occurrence and development of coronary atherosclerotic plaque in Chinese mini-swine.

[Effect of formula of removing both phlegm and blood stasis in improving hemorheology and blood fat of mini-swine with coronary heart disease of phlegm-stasis cementation syndrome].

OBJECTIVE: To observe effect of formula of removing both phlegm and blood stasis (TYTZ) in improving hemorheology and blood fat of mini-swine with coronary heart disease of phlegm-stasis cementation syndrome. METHOD: Thirty-six Chinese mini-swine were randomly divided to six groups: the normal control group, the model group, the Shujiangzhi group and TYTZ groups with doses of 2.0, 1.0 and 0.5 g x kg(-1), with six mice in each group. Except for the normal control group, all of other groups were fed with high-fat diet for 2 weeks. Interventional balloons are adopted to injure their left anterior descending artery endothelium. After the operation, they were fed with high-fat diet for 8 weeks to prepare the coronary heart disease model of phlegm-stasis cementation syndrome. In the 8th week after the operation and administration, the changes in hemorheological parameters, serum lipid level, myocardial ischemia level and range were observed. RESULT: Compared with the normal control group, the model group showed significant increase in serum TC, TG, LDL-C and VLDL-C levels (P < 0.01), whole blood viscosity under the shear rate of 5 s (-1) and 60 s (-1) (P < 0.01), and myocardial ischemia degree and range (P < 0.01). Compared with the model group, TYTZ groups revealed significant decrease in myocardial ischemia degree and range (P < 0.01), serum TC, TG, LDL-C and VLDL-C levels (P < 0.05 or P < 0.01) and whole blood viscosity under the shear rate of 5 s(-1) and 60 s(-1) (P < 0.05). CONCLUSION: TYTZ could improve the abnormal hemorheology in Chinese mini-swine with coronary heart disease of phlegm-stasis cementation syndrome, and regulate serum lipid, with a certain efficacy for coronary heart disease of phlegm-stasis cementation syndrome.

[Significance of serum MMP-3, TIMP-1, and monocyte CD147 in rheumatoid arthritis patients of damp-heat Bi-syndrome and of cold-damp Bi-syndrome].

OBJECTIVE: To explore the clinical significance of serum matrix metalloproteinase-3 (MMP-3), tissue inhibitor of metalloproteinase-1 (TIMP-1), and monocyte CD147 in rheumatoid arthritis (RA) patients of damp-heat Bi-syndrome (DHBS) and of cold-damp Bi-syndrome (CDBS). METHODS: The clinical data of 22 patients from inpatients and outpatients with RA were collected, and their peripheral blood was withdrawal. The disease activity scores [DAS28(4)] were assessed. The serum levels of MMP-3 and TIMP-1 were detected by double antibody sandwich enzyme linked immunosorbent assay (ELISA). The mean fluorescence intensity (MFI) and the expression percentage of CD147 on CD14+ monocytes were detected by flow cytometry. The difference of each index between RA patients of DHBS and RA patients of CDBS was analyzed. RESULTS: The level of serum MMP-3 and the MFI of CD147 on the monocyte surface were obviously higher in RA patients of DHBS than in those of CDBS and the normal control group (P < 0.05). The concentration of serum TIMP-1 was obviously higher in RA patients of DHBS than in those of the normal control group (P < 0.05), while there was no statistical difference between the two syndrome types. The percentage of CD147 expression was obviously lower in DHBS than in those of CDBS and the normal control group (P < 0.05). CONCLUSIONS: Increased serum MMP-3 level of RA patients of DHBS might result in destroy of joint cartilages and sclerotin. The significant increase of MFI and decreased expression percentage of monocyte CD147 might be the results of increased disease activity of RA and monocyte migration to the synovial membrane tissue.

[Effect of sailuotong capsule on intervening cognitive dysfunction of multi-infarct dementia in rats].

OBJECTIVE: To study the effect of Sailuotong capsule (Sailuotong) on learning and memory functions of multi-infarct dementia (MID) rats and its mechanism. METHOD: All SD rats were divided into five groups, namely the sham operation group, the model group, the positive group, the low dosage Sailuotong-treated group and the high dosage Sailuotong-treated group. The multi-infarct dementia model was established by injecting the micro-sphere vascular occlusive agent. On the 10th day after the successful operation, the rats were administered intragastrically with distilled water, memantine hydrochloride (20 mg x kg(-1)) and Sailuotong (16.5 mg x kg(-1) and 33.0 mg x kg(-1)) once a day for 60 days respectively, in order to detect the effect of Sailuotong in different doses on the latent period and route length in Morris water maze and the activities of choline acetyltransferase (ChAT) and acetylcholinesterase (AchE) in brain tissues. RESULT: Compared with the sham operation rats, it had been observed that the latent period and route length of MID rats in Morris water maze were significantly increased (P < 0.05 or P < 0.01), and the activity of ChAT in brain tissues was significantly decreased (P < 0.05). After the intervention with Sailuotong for sixty days, the latent period and route length of MID rats in Morris water maze significantly shrank (P < 0.05 or P < 0.01). Additionally, Sailuotong decreased AchE activity, while increasing ChAT activity in brain tissues of MID rats (P < 0.05 or P < 0.01). CONCLUSION: Sailuotong capsule can improve cognitive dysfunction of MID rats to some extent. Its mechanism may be related to its different regulation of activities of ChAT and AchE in brain tissues.

Silver-coated magnetite-carbon core-shell microspheres as substrate-enhanced SERS probes for detection of trace persistent organic pollutants.

Highly active surface-enhanced Raman scattering (SERS) substrates of Ag nanoparticle (Ag-NP) modified Fe(3)O(4)@carbon core-shell microspheres were synthesized and characterized. The carbon coated Fe(3)O(4) microspheres were prepared via a one-pot solvothermal method and were served as the magnetic supporting substrates. The Ag-NPs were deposited by in situ reduction of AgNO(3) with butylamine and the thickness of the Ag-NP layer was variable by controlling the AgNO(3) concentrations. The structure and integrity of the Fe(3)O(4)@C@Ag composite microspheres were confirmed by TEM, XRD, VSM and UV-visible spectroscopy. In particular, the Ag-NP coated Fe(3)O(4)@carbon core-shell microspheres were shown to be highly active for SERS detections of pentachlorophenol (PCP), diethylhexyl phthalate (DEHP) and trinitrotoluene (TNT). These analytes are representatives of environmentally persistent organic pollutants with typically low SERS activities. The results suggested that the interactions between the carbon on the microsphere substrates and the aromatic cores of the target molecules contributed to the facile pre-concentration of the analytes near the Ag-NP surfaces.

[Activities of daily living and demand for care of the elderly with chronic conditions in Chengdu].

OBJECTIVE: To evaluate the activities of daily living and demand for care of the elderly with chronic conditions in Chengdu in order to develop appropriate care models. METHODS: Convenient sampling strategy was adopted to recruit participants in four communities in Chengdu. A total of 180 elderly respondents with chronic conditions completed a questionnaire survey, which evaluated the activities of daily living and demand for care of the respondents. RESULTS: More than 77% respondents suffered from two or more chronic conditions. Over 97% respondents followed medical advices of doctors in drug therapy, with 70% monitoring the effectiveness of the drug therapy by themselves. The chronic conditions of 61% of respondents were well controlled. More than 54% were able to perform activities of daily living; 38% needed assistance; and 8% were completely dependent on others. Age and numbers of conditions influenced the activities of daily living (P < 0.005). Over 98% respondents were aware of their care needs and 1% identified unmet needs. Care for elderly came mainly from families, followed by relatives, friends, neighbors and workmates. Demands for care depended on financial capacity, degree of independence and numbers of conditions. Demands for nursing care increased with numbers of conditions (P < 0.05). CONCLUSION: The ability of elderly performing activities of daily living decreases with age and chronic conditions. A multidimensional care model involving professional carers needs to be developed in responding to the increasing needs of aged care.

[Using PAA template to fabricate SERS substrate and the SERS detection of melamine].

The authors have got silver film with orderly arranged nanoparticles as the surface-enhanced Raman spectra (SERS) substrates using porous anodic alumina templates (PAA). A silver film (99.99%) with the thickness of several millimeters was thermally evaporated onto the PAA templates and the SERS substrate was got after removing the PAA templates in hydrochloric acid. SERS spectra of pyridine (0.01 mol x L(-1)) were measured on Renishaw 2000 Ramanscope with a He-Ne (632.8 nm) laser as an excitation source in backscattering geometry, and the average enhancement factors were more than 10(5). The authors compared SERS spectra of pyridine from the SERS substrates and from Ag film evaporated directly on glass slide, and the former was 30 times stronger than the latter. The authors got different SERS spectra of pyridine while changing the excitation laser power. It was found that the relationship between the peak intensity of SERS spectra and the excitation laser power was linear as the normal Raman spectrum. We used the substrates to detect melamine, 2.5 mg x L(-1) melamine solution could be recognized al though excitation laser power was below 1 mW.

Pretreatment of plasma samples by a novel hollow fiber centrifugal ultrafiltrate device for the determination of cefaclor concentrations in human plasma.

A simple sample preparation method was developed by using a centrifugal ultrafiltration (CF-UF) device with hollow fiber (HF) for the determination of cefaclor in plasma by HPLC. Samples were placed into a homemade device, which was consisted of a glass tube and a U-shaped hollow fiber. The filtrate was withdrawn from the hollow fiber into a syringe after centrifugation and 20 µL was directly injected into the HPLC for analysis. The HPLC method had a linear calibration curve in the concentration range of 6.00×10(-2)-30.7 µg mL(-1)(r=0.9996). The limit of detection (LOD) and limit of quantitation (LOQ) were 0.02 and 0.06 µg mL(-1), respectively. The intra and inter-day precisions (RSD) were 1.7%, 1.2%, 1.0% and 3.6%, 2.5%, 1.9%, respectively, for three concentrations. Assay accuracy was higher than 99.2% and the absolute recovery was 86.8-92.5%. It is feasible to use this novel and low cost device for sample pretreatment for the analysis of cefaclor in plasma.

[Limited determination of trace toxical aconitine alkaloid in guifudihuang pills].

OBJECTIVE: To establish a capillary electrophoresis with field-amplified sample stacking method for the separation and determination of aconitine alkaloid in Guifudihuang pills. METHOD: An uncoated fused-silica capillary column (50 microm x 43 cm, effective length 35 cm) was used. The running buffer was 50 mmol x L(-1) phosphate electrolyte solution (pH 4.6)-methanol (8:2). The runing voltage was 10 kV and the capillary inlet was dipped in methanol for 5 s prior to electrokinetic injection (10 kV, 40 s). The detection wavelength was 235 nm. RESULT: This method allowed 500 fold enrichment of aconitine alkaloid. A good linear relation was obtained in the range of 31.3-2 x 10(3) microg x L(-1) (r = 0.9996), with the detection limit of 9.4 microg x L(-1). The average recovery was 98.0% with the RSD of 2.6%. CONCLUSION: The method is simple, rapid and specific with high stacking efficiency; it provides a new reliable means for production and quality control of Guifudihuang pills.