Global, but not chondrocyte-specific, MT1-MMP deficiency in adult mice causes inflammatory arthritis.

Membrane-type I metalloproteinase (MT1-MMP/MMP14) plays a key role in various pathophysiological processes, indicating an unaddressed need for a targeted therapeutic approach. However, mice genetically deficient in Mmp14 show severe defects in development and growth. To investigate the possibility of MT1-MMP inhibition as a safe treatment in adults, we generated global Mmp14 tamoxifen-induced conditional knockout (Mmp14kd) mice and found that MT1-MMP deficiency in adult mice resulted in severe inflammatory arthritis. Mmp14kd mice started to show noticeably swollen joints two weeks after tamoxifen administration, which progressed rapidly. Mmp14kd mice reached a humane endpoint 6 to 8 weeks after tamoxifen administration due to severe arthritis. Plasma TNF-α levels were also significantly increased in Mmp14kd mice. Detailed analysis revealed chondrocyte hypertrophy, synovial fibrosis, and subchondral bone remodeling in the joints of Mmp14kd mice. However, global conditional knockout of MT1-MMP in adult mice did not affect body weight, blood glucose, or plasma cholesterol and triglyceride levels. Furthermore, we observed substantial expression of MT1-MMP in the articular cartilage of patients with osteoarthritis. We then developed chondrocyte-specific Mmp14 tamoxifen-induced conditional knockout (Mmp14chkd) mice. Chondrocyte MT1-MMP deficiency in adult mice also caused apparent chondrocyte hypertrophy. However, Mmp14chkd mice did not exhibit synovial hyperplasia or noticeable arthritis, suggesting that chondrocyte MT1-MMP is not solely responsible for the onset of severe arthritis observed in Mmp14kd mice. Our findings also suggest that highly cell-type specific inhibition of MT1-MMP is required for its potential therapeutic use.

Ultrasensitive PEC cytosensor for breast cancer cells detection and inhibitor screening based on plum-branched CdS/Bi2S3 heterostructures.

Breast cancer is the most common malignant tumor in women, which seriously threatens the life and health of patients. Therefore, facile and sensitive detection of human breast cancer cells is crucial for cancer diagnosis. In this work, plum-branched CdS/Bi2S3 heterostructures (CdS/Bi2S3 HSs) were synthesized under hydrothermal condition, whose photoelectrochemical (PEC) property and biocompatibility were scrutinously investigated. In parallel, a signal amplification strategy was designed based on immune recognition between epidermal growth factor receptor (EGFR) overexpressed on membrane of breast cancer cells MDA-MB-231 and its aptamer. Integration of the above together, a highly sensitive PEC cytosensor was developed for analysis of target MDA-MB-231 cells, exhibiting a wider linear range of 1 × 102 âˆ¼ 3 × 105 cells mL-1 with a limit of detection (LOD) down to 6 cells mL-1 (S/N = 3). Further, the biosensor was explored for anticancer drug (e.g., dacomitinib) screening by monitoring the variations in the PEC signals of the expressed EGFR upon drug stimulation. The obtained CdS/Bi2S3 HSs are identified as promising and feasible photoactive material for determination of cancer cells and drug screening in clinic and related research.

Z-scheme Cu2MoS4/CdS/In2S3 nanocages heterojunctions-based PEC aptasensor for ultrasensitive assay of fumonisin B1 via signal amplification with hollow PtPd-CoSnO3 nanozyme.

Fumonisin B1 (FB1), the most prevalent and highest toxicity mycotoxins among fumonisins family, poses threats to human especially children and infants even at a trace level. Therefore, its facile and sensitive detection is of importance. Herein, Z-scheme Cu2MoS4/CdS/In2S3 nanocage-like heterojunctions (labeled Cu2MoS4/CdS/In2S3) were synthesized, whose photoelectrochemical (PEC) property and electron transfer mechanism were strictly investigated. The Cu2MoS4/CdS/In2S3 behaved as photoactive substrate for building a PEC sensing platform for detection of FB1, integrated with PtPd alloy modified hollow CoSnO3 nanoboxes (labeled PtPd-CoSnO3) nanozyme. By virtue of the stronger affinity between the target FB1 and its aptamer (FB1-Apt), the photocurrent was recovered by releasing the CoSnO3-PtPd3 modified FB1-Apt (FB1-Apt/PtPd-CoSnO3) from the photoanode, which can terminate the catalytic precipitation reaction for its peroxidase-like property. The resultant PEC aptasensor exhibited a wider dynamic linear range from 1 × 10-4 to 1 × 102 ng mL-1 with a lower limit of detection (0.0723 pg mL-1). Thus, this research provides a feasible PEC sensing platform for routine analysis of other mycotoxins in practice.

Dual II-scheme nanosheet-like Bi2S3/Bi2O3/Ag2S heterostructures for ultrasensitive PEC aptasensing of aflatoxin B1 coupled with catalytic signal amplification by dendritic nanorod-like Au@Pd@Pt nanozyme.

As one of the most toxic chemical substances, aflatoxin B1 (AFB1) has a strong carcinogenic effect even at a trace level in human and animal, which severely threatens human health and even causes cancers. Therefore, ultrasensitive detection of AFB1 is of significant importance. For such analysis, dual II-scheme sheet-like Bi2S3/Bi2O3/Ag2S heterostructures were prepared by the in-situ growth method, which exhibited high separation efficiency for the electron-hole (e--h+) pairs, prominent stability, and high photoactivity. Moreover, the dendritic nanorod-like Au@Pd@Pt (Au@Pd@Pt DNRs) nanozyme was homely synthesized, whose peroxidase-like activity was scrupulously investigated by catalytical oxidation of diaminobenzidine (DAB) in the presence of H2O2. Integration by the aptasensing strategy, a photoelectrochemical (PEC) "signal-on" aptasensor was prepared, which exhibited a broader linear range of 0.5 pg mL-1-100 ng mL-1 with a lower limit of detection (LOD = 0.09 pg mL-1, S/N = 3). This work provides a feasible strategy to develop advanced PEC biosensors for actual analysis of environmental pollutants.

Identification of amino acid residues in the MT-loop of MT1-MMP critical for its ability to cleave low-density lipoprotein receptor.

Low-density lipoprotein receptor (LDLR) mediates clearance of plasma LDL cholesterol, preventing the development of atherosclerosis. We previously demonstrated that membrane type 1-matrix metalloproteinase (MT1-MMP) cleaves LDLR and exacerbates the development of atherosclerosis. Here, we investigated determinants in LDLR and MT1-MMP that were critical for MT1-MMP-induced LDLR cleavage. We observed that deletion of various functional domains in LDLR or removal of each of the five predicted cleavage sites of MT1-MMP on LDLR did not affect MT1-MMP-induced cleavage of the receptor. Removal of the hemopexin domain or the C-terminal cytoplasmic tail of MT1-MMP also did not impair its ability to cleave LDLR. On the other hand, mutant MT1-MMP, in which the catalytic domain or the MT-loop was deleted, could not cleave LDLR. Further Ala-scanning analysis revealed an important role for Ile at position 167 of the MT-loop in MT1-MMP's action on LDLR. Replacement of Ile167 with Ala, Thr, Glu, or Lys resulted in a marked loss of the ability to cleave LDLR, whereas mutation of Ile167 to a non-polar amino acid residue, including Leu, Val, Met, and Phe, had no effect. Therefore, our studies indicate that MT1-MMP does not require a specific cleavage site on LDLR. In contrast, an amino acid residue with a hydrophobic side chain at position 167 in the MT-loop is critical for MT1-MMP-induced LDLR cleavage.

Novel Ultrasensitive Photoelectrochemical Cytosensor Based on Hollow CdIn2S4/In2S3 Heterostructured Microspheres for HepG2 Cells Detection and Inhibitor Screening.

Hepatocellular carcinoma is a life-threatening malignant tumor found around the world for its high morbidity and mortality. Therefore, it is of great importance for sensitive analysis of liver cancer cells (HepG2 cells) in clinical diagnosis and biomedical research. To fulfill this demand, hollow CdIn2S4/In2S3 heterostructured microspheres (termed CdIn2S4/In2S3 for clarity) were prepared by a two-step hydrothermal strategy and applied for building a novel photoelectrochemical (PEC) cytosensor for ultrasensitive and accurate detection of HepG2 cells through specific recognition of CD133 protein on the cell surface with the respective aptamer. The optical properties of CdIn2S4/In2S3 were investigated by UV-vis diffuse reflectance spectroscopy (DRS) and PEC technology. By virtue of their appealing PEC characteristics, the resultant PEC sensor exhibited a wider dynamic linear range from 1 × 102 to 2 × 105 cells mL-1 with a lower limit of detection (LOD, 23 cells mL-1), combined by evaluating the expression level of CD133 protein stimulated by metformin as a benchmarked inhibitor. This work opens a valuable and feasible avenue for sensitive detection of diverse tumor cells, holding great potential in early clinical diagnosis and treatment coupled by screening inhibitors.

Heterostructured BiVO4/CoPi nanoarrays as high-efficiency photoanode and AuPt nanodendrites as nanozyme for sensitive sensing of miRNA 141.

MicroRNA (miRNA) is a new class of tumor biomarkers in human body for early diagnosis and therapy of cancers, whose detection has scientific significance and potential applications. Herein, a sensitive heterostructured BiVO4/CoPi photoelectrochemical (PEC) biosensor was established for sensing miRNA 141 with assistance of home-synthesized AuPt nanodendrites (NDs) as nanozyme. Specifically, the BiVO4/CoPi heterostructures displayed rough worm-like internetworks, as characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). In parallel, the PEC and UV-vis diffuse reflectance spectroscopy tests confirmed their excellent optical property, combined by discussing the interfacial electron transfer mechanism. Additionally, the AuPt NDs displayed superior peroxidase-like property in the presence of H2O2 as identified by benchmarked tetramethylbenzidine (TMB) oxidation, coupled by showing remarkable catalysis for 3-amino-9-ethylcarbazole (AEC) oxidation to form biocatalytic precipitation (BCP). Integrated by a cyclic enzyme strategy, the developed PEC biosensor exhibited a wider linear range of 5 fM ∼1 pM and a lower limit of detection (LOD) as low as 0.17 fM (S/N = 3). This work provides some valuable insights for sensitive analysis of tumor-associated miRNA in clinic.

Regulation of PCSK9 Expression and Function: Mechanisms and Therapeutic Implications.

Proprotein convertase subtilisin/kexin type 9 (PCSK9) promotes degradation of low-density lipoprotein receptor (LDLR) and plays a central role in regulating plasma levels of LDL cholesterol levels, lipoprotein(a) and triglyceride-rich lipoproteins, increasing the risk of cardiovascular disease. Additionally, PCSK9 promotes degradation of major histocompatibility protein class I and reduces intratumoral infiltration of cytotoxic T cells. Inhibition of PCSK9 increases expression of LDLR, thereby reducing plasma levels of lipoproteins and the risk of cardiovascular disease. PCSK9 inhibition also increases cell surface levels of major histocompatibility protein class I in cancer cells and suppresses tumor growth. Therefore, PCSK9 plays a vital role in the pathogenesis of cardiovascular disease and cancer, the top two causes of morbidity and mortality worldwide. Monoclonal anti-PCSK9 antibody-based therapy is currently the only available treatment that can effectively reduce plasma LDL-C levels and suppress tumor growth. However, high expenses limit their widespread use. PCSK9 promotes lysosomal degradation of its substrates, but the detailed molecular mechanism by which PCSK9 promotes degradation of its substrates is not completely understood, impeding the development of more cost-effective alternative strategies to inhibit PCSK9. Here, we review our current understanding of PCSK9 and focus on the regulation of its expression and functions.

Membrane-type I matrix metalloproteinase (MT1-MMP), lipid metabolism, and therapeutic implications.

Lipids exert many essential physiological functions, such as serving as a structural component of biological membranes, storing energy, and regulating cell signal transduction. Dysregulation of lipid metabolism can lead to dyslipidemia related to various human diseases, such as obesity, diabetes, and cardiovascular disease. Therefore, lipid metabolism is strictly regulated through multiple mechanisms at different levels, including the extracellular matrix. Membrane-type I matrix metalloproteinase (MT1-MMP), a zinc-dependent endopeptidase, proteolytically cleaves extracellular matrix components, and non-matrix proteins, thereby regulating many physiological and pathophysiological processes. Emerging evidence supports the vital role of MT1-MMP in lipid metabolism. For example, MT1-MMP mediates ectodomain shedding of low-density lipoprotein receptor and increases plasma low-density lipoprotein cholesterol levels and the development of atherosclerosis. It also increases the vulnerability of atherosclerotic plaque by promoting collagen cleavage. Furthermore, it can cleave the extracellular matrix of adipocytes, affecting adipogenesis and the development of obesity. Therefore, the activity of MT1-MMP is strictly regulated by multiple mechanisms, such as autocatalytic cleavage, endocytosis and exocytosis, and post-translational modifications. Here, we summarize the latest advances in MT1-MMP, mainly focusing on its role in lipid metabolism, the molecular mechanisms regulating the function and expression of MT1-MMP, and their pharmacotherapeutic implications.

The long-non-coding RNA NEAT1 is a novel target for Alzheimer's disease progression via miR-124/BACE1 axis.

OBJECTIVES: Long-non-coding RNAs (lncRNAs) have been involved in central nervous system recently. A number of studies have reported that lncRNA NEAT1 exerts critical roles in neurodegenerative disorder. Beta-site amyloid precursor protein cleaving enzyme 1 (BACE1) has been reported to exert function in the accumulation of amyloid-ß (Aß). Moreover, BACE1 acts as a target of miR-124 in the progression of AD. So far, the biological role and underlying mechanisms of NEAT1 and miR-124 in AD remains elusive. METHODS: The relative NEAT1 and miR-124 expression was examined by qRT-PCR in the tissues and cells line of AD. Cell apoptosis was examined by FACS. Luciferase reporter assay was performed to verify that miR-124 is a direct target of NEAT1, and BACE1 is a downstream target of miR-124. qRT-PCR and western blot analysis were also performed to determinate the BACE1 and the phosphorylation of tau protein. RESULTS: NEAT1 was notably up-regulated and miR-124 was remarkably down-regulated in AD mouse model. Knockdown of NEAT1 or overexpression of miR-124 showed the protective effects on cellular AD model induced by Aß. Moreover, miR-124 expression could be up- and down-regulated by suppression or overexpression of NEAT1, respectively. In addition, the expression of BACE1 was the potential functional target of miR-124. These findings suggested that NEAT1 might play a vital role in the development of AD by regulating miR-124/BACE1 axis. DISCUSSION: The present study showed that NEAT1 worked as a regulating factor to promote the development of AD via modulating miR-124/BACE1 axis, which might be considered as a novel target in AD treatment.

Spirometric prediction equations and the relationship between metabolic syndrome and spirometric parameters from an island in Fujian, China.

BACKGROUND: We investigated risk factors for decreased lung function among Chinese island residents (≥30 years) to determine the relationship between metabolic syndrome (MS) and decreased lung function. METHODS: From October 17, 2011 to November 1, 2011, 2607 residents aged ≥30 years who lived on the Huangqi Peninsula of Fujian were enlisted by random cluster sampling. They completed a questionnaire designed according to the Burden of Obstructive Lung Disease (BOLD) questionnaire, and underwent physical examination, blood test, and lung function evaluation. We constructed spirometric prediction equations for forced vital capacity (FVC) and forced expiratory volume in one second (FEV1), determined the lower limits of normal for FVC, FEV1 and FEV1/FVC, and examined the relationship between lung function and MS. RESULTS: Prediction equations for normal island residents were as follows: FVC (L) = -0.023 × age (years) + 0.042 × height (cm) + 0.641 × weight (kg) - 3.607 (males); FVC (L) = -0.017 × age (years) + 0.030 × height (cm) + 0.009 × weight (kg) - 1.741 (females); FEV1 (L) = -0.023 × age (years) + 0.040 × height (cm) + 0.010 × weight (kg) - 2.999 (males); FEV1 (L) = -0.017 × age (years) + 0.026 × height (cm) + 0.007 × weight (kg) -1.135 (females). The odds ratio for MS for increased risk of decreased FVC was 4.623 (95%CI =3.626-5.894, P<0.001), and for increased risk of decreased FEV1 was 3.043 (95%CI =2.447-3.785, P<0.001). CONCLUSIONS: MS is a risk factor for decreased lung function in island residents ≥30 years old.

Local injection of lentivirus-delivered livinshRNA suppresses lung adenocarcinoma growth by inducing a G0/G1 phase cell cycle arrest.

The inhibitor of apoptosis protein (IAP) plays an important role in tumorigenesis and may be a potential target for cancer therapy. Livin, which belongs to this family, is highly expressed in various tumors. The previous study demonstrated that silencing Livin gene promoted lung cancer cell apoptosis; however, the effects on tumor growth suppression by targeting this gene in vivo, to thereby determine the efficacy of targeting Livin for patient therapy, have not been determined. This study injected lentivirus-delivered livinshRNA into established xenograft tumors derived from the lung adenocarcinoma cell line SPC-A-1 in BALB/C nude mice, the result showed that LivinshRNA down-regulated Livin expression effectively, induced tumor cell apoptosis, reduced tumor cell proliferation, and suppressed tumor growth dramatically, with a tumor volume inhibitory rate of (58.65±4.82)% and a tumor weight inhibitory rate of (47.44±1.64)%, but with less severe adverse reaction to the mouse. This study further demonstrated that Livin gene silencing induced a G0/G1-phase cell cycle arrest and cyclin D1 downregulation, which is a key regulator of the G0/G1- to S-phase transition. These findings suggest that LivinshRNA local injection may serve as a therapeutic method for patient treatment, and that LivinshRNA may suppress tumor growth by arresting the cell cycle in the G0/G1-phase.

[Study on over-weight, obesity and the exposure to stroke risk factors among 40 year olds and over in a community-based population].

OBJECTIVE: To describe the distribution of over weight and obesity to discover the level of exposure on risk factors of stroke among people aged 40 and over, in a community-based population. METHODS: From 2003 to 2004, people aged > or = 40 years in a community of Fengxian district in Shanghai were selected by cluster sampling. Out of 11,791 individuals who were selected, 10,565 met the inclusion criteria and responded to the investigation. By face to face interview, a cross-sectional survey was carried out, using a questionnaire for risk factors of stroke. Height, weight and blood pressures were measured and cerebrovascular hemodynamic parameters (CVHP) were checked. Age and gender distribution of over weight and obesity in the population were described. Using 60 year as cut-off point, participants were grouped into three: normal, over weight and obesity by body mass index. Level of stroke risk factor exposure between groups was compared and logistic regression model was used for multiple analyses. RESULTS: Proportions of over weight and obesity were 28.5 percent and 4.1 percent in male and 26.3 percent and 4.2 percent in female (P = 0.045). Systolic and diastolic blood pressure in over weight group were (132.5 +/- 19.4) mm Hg and (83.9 +/- 10.5) mm Hg (1 mm Hg = 0.133 kPa), which were higher than that in normal weight group and lower than that in obese group (P < 0.05). Exposure rate of heart disease, family history of stroke in < 60 year old group and diabetes in > or = 60 year group increased along with the increase of weight. Exposure rate of hypertension, abnormality of CVHP score in both age groups were also increased with the increase of weight. Data from multiple logistic regression indicated that hypertension, family history of stroke and heart disease, CVHP score below 75 points, sex and age were independent factors of over weight and obese. CONCLUSION: The prevalence of over weight or obesity in a community-based population among aged 40 years or over was around 30 percent. The overall exposure rate of stroke risk factors were increasing along with the increase of weight, especially for those in the middle age.

[Differential expression of USP2, USP14 and UBE4A between ovarian serous cystadenocarcinoma and adjacent normal tissues].

AIM: The differential expression of USP2, USP14 and UBE4A between ovarian serous cystadenocarcinoma and adjacent normal tissues was investigated. METHODS: Restriction fragment differential display polymerase chain reaction (RFDD-PCR), semi-quantitative RT-PCR and immunohistochemical staining were applied to analyze the differentially expressed genes and proteins of ubiquitin specific proteases (USPs), USP2 and USP14, and ubiquitin factor E4A (UBE4A) between ovarian serous cystadenocarcinoma and adjacent normal tissues obtained from 40 patients aged from 29 to 72 years old, collected in 2005 year at excision of surgical operation with ovarian serous cystadenocarcinoma. RESULTS: USP2, USP14 and UBE4A were over-expressed (>3 folds) in ovarian serous cystadenocarcinoma tissues compared to normal tissues. CONCLUSION: The results suggest that the activity of ubiquitin-proteasome system is obviously enhanced in ovarian cancer.

[Baseline study and analysis on a stroke risk factor-related cohort in Fengxian county of Shanghai].

OBJECTIVE: To explore the exposed level of stroke risk factors in Fengxian county of Shanghai and the relationships between risk factors and stroke. METHODS: Community based populations including 10,565 individuals aged 40 years old and over were cluster sampled from Fengxian county in 2003 or 2004. Status of exposure on common risk factors such as hypertension, cardiovascular disease, diabetes, family history of stroke, cigarette smoking, alcohol intake were gathered while cerebral vascular hemodynamic index (CVHI) was examined, with CVHI score below 75 points as abnormal. During 2003 to 2006, 78 stroke cases occurred. The relationships between risk factors and stroke were analyzed by univariate and Cox proportional hazards regression models. RESULTS: Rates of exposure regarding hypertension, cardiovascular disease, diabetes, family history of stroke, obesity (BMI > or = 28 kg/m2), smoking, drinking and CVHI score abnormal were 21.14%, 6.72%, 1.88%, 5.63%, 4.17%, 34.96%, 17.81% and 29.43%, respectively. Data from Univariate analysis indicated that relative risk (95% CI) of above-mentioned risk factors were 2.76 (1.76-4.32), 2.19 (1.16-4.14), 1.52 (0.38-6.19), 1.58 (0.69-3.62), 1.24 (0.45-3.38), 1.75 (1.12-2.73), 2.10 (1.30-3.39) and 12.72 (7.02-23.06), respectively. Results from Cox proportional hazards regression models analysis showed that cigarette smoking, CVHI score abnormal were screened into equation. CONCLUSION: Among all the risk factors, rate of hypertension was the highest while hypertension, cardiovascular disease, cigarette smoking, alcohol intake and abnomal CVHI score had remarkable etiological correlations to stroke. Abnormal CVHI score, cigarette smoking seemed to be the independent forecasting factors related to stroke.

[Baseline study on a stroke-related cohort in the rural community of Shanghai].

OBJECTIVE: To present data from a baseline investigation on stroke-related cohort population in rural area of Shanghai. METHODS: A cross-sectional study was carried out in a cluster sampling population aged 40 years and over. General information and data on common risk factors in the population were gathered and cerebral vascular hemodynamic indexes were checked. Hemodynamic score was estimated according to single indexes by unified methods. 5335 persons who had met the inclusion criteria were enlisted in the study. Exposure level of risk factors, prevalence of stroke, and hemodynamic indexes were analyzed and distributional characteristics were described. RESULTS: Exposure rate of hypertension, heart disease, diabetes, family history of hypertension, overweight or obesity in males were 31.74%, 6.09%, 1.16%, 3.22%, 17.64%, 29.68% and were 32.76%, 9.22%, 1.55%, 3.84%, 19.22%, 29.44% in female respectively. Standard prevalence of stroke was 1167.3/100000, which in male was significantly higher than that in female (P < 0.05). The change of cerebral vascular hemodynamic indexes was significantly associated with age. Hemodynamic score in 21.3% of the subjects was below 75 points. CONCLUSIONS: Among population of 40 years old and over in rural areas, hypertension was the principal risk factor regarding the rate of stroke. Prevalence of stroke in males was significantly higher than that in females. Abnormal rate of hemodynamic score was about 20% in this population.

[Effectiveness of Nao'an Capsule on stroke prevention among high risk population in Nanhui, Shanghai].

OBJECTIVE: To evaluate the effectiveness of stroke prevention among high risk population, using Nao'an Capsules. METHODS: Participants were selected from 696,558 residents in Nanhui, using county of Shanghai city. Individuals aged 35 years old and over with at least one risk factor exposure to stroke, received cerebral vascular hemodynamic examination. 18,271 cases meeting the criteria of cerebral vascular hemodynamic indexes accumulative score below 70 points were defined as individuals with high-risk and targets to receive intervention. According to the willingness of the participants, 10,313 cases received Nao'an Capsules for intensive intervention based on general intervention measures compared to 7958 cases only receiving general intervention. After the implementation of intervention, incidence and mortality rates of stroke and the effectiveness of three-year intervention were studied. RESULTS: Incidence of stroke in Nao'an Capsules group was significantly lower than that of the general intervention (P < 0.01) with 53.8% in males and 58.4% in females. The relative risk (RR) in two gender groups were 0.46 (0.33 - 0.64) and 0.39 (0.30 - 0.50) respectively. Multiple logistic regression analysis indicated that the history of hypertension, accumulative score of cerebral vascular hemodynamic indexes, age, gender and Nao'an Capsules intervention were the variables selected into the equation and significantly related to stroke. Among the variables, Nao'an Capsule was the strongest factor with a RR of 0.41. CONCLUSION: Incidence of stroke in Nao'an Capsule intervention group was significantly lower than that in the general intervention group after 3 years of intervention, suggesting that Nao'an Capsule intervention was the strongest factor affecting stroke occurrence in individuals at high-risk.

Biocompatible and biodegradable polymer nanofibers displaying superparamagnetic properties.

Superparamagnetic polymer nanofibers intended for drug delivery and therapy are considered here. Magnetite (Fe3O4) nanoparticles in the diameter range of 5-10 nm were synthesized in aqueous solution. Polymer nanofibers containing magnetite nanoparticles were prepared from commercially available poly(hydroxyethyl methacrylate), PHEMA, and poly-L-lactide (PLLA) by the electrospinning technique. Nanofibers with diameters ranging from 50 to 300 nm were obtained. Nanofibers containing up to 35 wt % magnetite nanoparticles displayed superparamagnetism at room temperature. The blocking temperature was about 50 K for an applied field of 500 Oe, and the saturation magnetization was 3.5 emu g(-1) and 1.1 emu g(-1) for Fe3O4/PHEMA and Fe3O4/PLLA nanofibers, respectively, and depended on the amount of Fe3O4 nanoparticles in the nanocomposites. To test such magnetic nano-objects for applications as drug carriers and drug-release systems we incorporated a fluorescent albumin with dog fluorescein isothiocyanate (ADFI).