Machine learning is an effective method to predict the 90-day prognosis of patients with transient ischemic attack and minor stroke.

OBJECTIVE: We aimed to investigate factors related to the 90-day poor prognosis (mRS≥3) in patients with transient ischemic attack (TIA) or minor stroke, construct 90-day poor prognosis prediction models for patients with TIA or minor stroke, and compare the predictive performance of machine learning models and Logistic model. METHOD: We selected TIA and minor stroke patients from a prospective registry study (CNSR-III). Demographic characteristics,smoking history, drinking history(≥20g/day), physiological data, medical history,secondary prevention treatment, in-hospital evaluation and education,laboratory data, neurological severity, mRS score and TOAST classification of patients were assessed. Univariate and multivariate logistic regression analyses were performed in the training set to identify predictors associated with poor outcome (mRS≥3). The predictors were used to establish machine learning models and the traditional Logistic model, which were randomly divided into the training set and test set according to the ratio of 70:30. The training set was used to construct the prediction model, and the test set was used to evaluate the effect of the model. The evaluation indicators of the model included the area under the curve (AUC) of the discrimination index and the Brier score (or calibration plot) of the calibration index. RESULT: A total of 10967 patients with TIA and minor stroke were enrolled in this study, with an average age of 61.77 ± 11.18 years, and women accounted for 30.68%. Factors associated with the poor prognosis in TIA and minor stroke patients included sex, age, stroke history, heart rate, D-dimer, creatinine, TOAST classification, admission mRS, discharge mRS, and discharge NIHSS score. All models, both those constructed by Logistic regression and those by machine learning, performed well in predicting the 90-day poor prognosis (AUC >0.800). The best performing AUC in the test set was the Catboost model (AUC=0.839), followed by the XGBoost, GBDT, random forest and Adaboost model (AUCs equal to 0.838, 0, 835, 0.832, 0.823, respectively). The performance of Catboost and XGBoost in predicting poor prognosis at 90-day was better than the Logistic model, and the difference was statistically significant(P<0.05). All models, both those constructed by Logistic regression and those by machine learning had good calibration. CONCLUSION: Machine learning algorithms were not inferior to the Logistic regression model in predicting the poor prognosis of patients with TIA and minor stroke at 90-day. Among them, the Catboost model had the best predictive performance. All models provided good discrimination.

Three New Aglain Derivatives from Aglaia odorata Lour. and Their Cytotoxic Activities.

Three new aglain derivatives (1-3), one known aglain derivative (4), two known rocaglamide derivatives (5 and 6), four known triterpenoids (7-10), and three steroids (11-13) were isolated from Aglaia odorata Lour. Their structures were established through the analysis of detailed spectroscopic data and electronic circular dichroism calculations. Five compounds (1 and 4-7) exhibited cytotoxic activities on human leukemia cells (HEL) and human breast cancer cells with IC50 values in the range of 0.03-8.40 µM. In particular, the cytotoxicity of compound 5 was six times stronger than that of the positive control (adriamycin) in HEL cell lines.

Atrial Fibrillation Known Before or Detected After Stroke Share Similar Risk of Ischemic Stroke Recurrence and Death.

Background and Purpose- We aim to compare the risk of 1-year ischemic stroke recurrence and death for atrial fibrillation diagnosed after stroke (AFDAS), atrial fibrillation known before stroke (KAF), and sinus rhythm (SR). Methods- From June 2012 to January 2013, 19 604 patients with acute ischemic stroke were admitted to 219 urban hospitals in the China National Stroke Registry II. Based on heart rhythm assessed during admission, we classified patients as AFDAS, KAF, or SR. We explored the relationship between heart rhythm groups and 1-year ischemic stroke recurrence or death by using Cox regression adjusted for multiple covariates. Considering that death is a competing risk for stroke recurrence, we used the competing risks analysis of Fine and Gray and subdistribution Cox proportional hazards to test the association between heart rhythm and 1-year outcomes. Results- Among 19 604 ischemic stroke patients, 17 727 had SR, 495 AFDAS, and 1382 KAF. At 1 year, 54 (10.9%) patients with AFDAS, 182 (13.2%) with KAF, and 1008 (5.7%) with SR had recurrent ischemic strokes ( P<0.0001). Mortality was 22.0% in patients with AFDAS, 22.1% in patients with KAF, and 7.0% in patients with SR ( P<0.0001). AFDAS-related ischemic stroke recurrence adjusted risk was higher than that of SR (adjusted subdistribution hazard ratios, 1.61; 95% CI, 1.29-2.01) but not different from that of KAF (adjusted subdistribution hazard ratio, 1.12; 95% CI, 0.87-1.45]). The adjusted risk of 1-year death for AFDAS was also higher than that of SR (hazard ratio, 1.70; 95% CI, 1.37-2.12) and not different from that of KAF (hazard ratio, 1.10; 95% CI, 0.86-1.41). Conclusions- This study showed that AFDAS had similar risk of 1-year ischemic stroke recurrence and mortality when compared with KAF and higher risk when compared with SR. The potential risk of AFDAS should be given more emphasis, and appropriate treatment is needed to achieve reduction in the incidence of stroke recurrence and mortality.

[Percentage of Th17 Cells in Spleen and IL-17 Level in Bronchoalveolar Lavage Fluid in Dermatophagoides farinae Allergic Asthma Mice].

OBJECTIVE: To detect the percentage of Th17 cells in spleen and IL-17 level in bronchoalveolar lavage fluid in Dermatophagoides farinae allergic asthma mice. METHODS: Twenty BALB/c mice were randomly divided into control group (n=10) and asthma group (n=10). Mice in control group were treated with PBS plus 2 mg Al(OH)3 and those in asthma group were sensitized with 200 µl solution [50 µg Dermatophagoides farinae crude extracts plus 2 mg Al (OH)3] on day 0, 7 and 14. One week after the last sensitization, all mice were intranasally challenged with 50 µg Dermatophagoides farinae crude extracts daily for 7 days. Twenty-four hours after the last challenge, mice were sacrificed. The sera, bronchoalveolar lavage fluid (BALF) and spleens were collected. The serum levels of IgE and IgG1, and IL-17 level in BALF were determined by ELISA. The percentage of Th17 cells in spleen was tested by flow cytometry. RESULTS: The serum levels of IgG, and IgE in asthma group were (0.10 ± 0.01) pg/ml and (1.15 ± 0.10) pg/ml, respectively, which were higher than that of the control [(0.06 ± 0.01) pg/ml and (0.04 ± 0.01) pg/ml] (P < 0.05). IL-17 level in asthma group (85.13 ± 2.36) pg/ml was higher than that of the control [(48.27 ± 4.14) pg/ml] (P < 0.01). The percentage of Th17 cells in asthma group [(5.19 ± 0.68)%] was also higher than that of the control [(0.95 ± 0.19)%] (P < 0.01). Meanwhile, the percentage of Thl7 cells in spleen was positively correlated with IL-17 level in BALF (r = 0.851, P < 0.01). CONCLUSION: Compared with healthy mice, both the percentage of Th17 cells in spleen and IL-17 level in BALF have increased significantly in Dermatophagoides farinae allergic asthma mice.

[The hepatic ChREBP expression and hyperinsulinemia in mice].

To explore the effects of serum insulin on the expression of ChREBP, ACC and FAS in vivo, KKAy mice which were characterized with high levels of both serum insulin and glucose and DIO mice which were characterized with high serum insulin level alone were utilized, separately. The age-matched C57BL/6J mice fed with standard chow were used as normal control (Con). Expressions of hepatic ChREBP, ACC and FAS were detected by Western blotting. As the results, in KKAy mice, a positive correlation between the levels of serum insulin and glucose (r = 0.902, P < 0.000), as well as between the levels of serum insulin and TG (r = 0.732, P < 0.000), was observed. Meanwhile, the expressions of hepatic ChREBP, ACC and FAS increased significantly and accompanied with its hyperinsulinemia and hyperglycemia, separately. In DIO mice, correlation between the levels of serum insulin and TG (r = 0.722, P < 0.001) also showed positive, and the expressions of hepatic ChREBP, ACC and FAS increased significantly and also accompanied with its hyperinsulinemia. However, their blood glucose values were almost normal. These demonstrated that hyperinsulinemia may cause glycolipid metabolic disorders by up-regulating the expression of ChREBP in vivo.

Modulating apoptosis as a novel therapeutic strategy against Respiratory Syncytial Virus infection: insights from Rotenone.

Respiratory syncytial virus (RSV) is a significant cause of acute lower respiratory tract infections, particularly in vulnerable populations such as neonates, infants, young children, and the elderly. Among infants, RSV is the primary cause of bronchiolitis and pneumonia, contributing to a notable proportion of child mortality under the age of 5. In this study, we focused on investigating the pathogenicity of a lethal RSV strain, GZ08-18, as a model for understanding mechanisms of hypervirulent RSV. Our findings indicate that the heightened pathogenicity of GZ08-18 stems from compromised activation of intrinsic apoptosis, as evidenced by aberration of mitochondrial membrane depolarization in host cells. We thus hypothesized that enhancing intrinsic apoptosis could potentially attenuate the virulence of RSV strains and explored the effects of Rotenone, a natural compound known to stimulate the intrinsic apoptosis pathway, on inhibiting RSV infection. Our results demonstrate that Rotenone treatment significantly improved mouse survival rates and mitigated lung pathology following GZ08-18 infection. These findings suggest that modulating the suppressed apoptosis induced by RSV infection represents a promising avenue for antiviral intervention strategies.

[Investigation of a compound, compatibility of Rhodiola crenulata, Cordyceps militaris, and Rheum palmatum, on metabolic syndrome treatment II - improving obesity].

To investigate the effect of compound FF16, compatibility of Rhodiola crenulata, Cordyceps militaris, and Rheum palmatum, on obesity, both the insulin resistant obese IRF mouse model induced by high fat diet and the spontaneous type 2 diabetes KKAy obese mouse model were used. The results showed that the body weights and the energy uptake were markedly reduced by compound FF16 in both IRF mice in dose-dependent manner and KKAy mice, respectively. Meanwhile, with the administration of FF16, the hypercholesterolemia and the hypertriglyceridemia were improved significantly in KKAy mice; and the levels of serum cholesterol and fatty index were decreased obviously, and the value of serum HDL-C was increased significantly in IRF mice, respectively. Moreover, the activity of a-glycosidase was inhibited by compound FF16 in vitro. In conclusion, FF16 could improve the obesity by inhibiting alpha-glycosidase activity.

[Investigation of a compound, compatibility of Rhodiola crenulata, Cordyceps militaris, and Rheum palmatum on metabolic syndrome treatment III--controlling blood glucose].

Base on the improvement of compound FF16, compatibility of Rhodiola crenulata, Cordyceps militaris, and Rheum palmatum, on both insulin resistance and obesity, its effects on type 2 diabetes (T2DM ) was investigated here. The results showed that the levels of fasting and no-fasting blood glucose were controlled in the spontaneous type 2 diabetes KKAy mice; the impaired glucose tolerance (IGT)was improved by decreasing significantly the values of the glucose peaks and the area under the blood glucose-time curve (AUC ) after glucose-loading in glucose tolerance test (OGTT) in both high-fat-diet-induced pre-diabetes IRF mice and KKAy mice, respectively. The pancreatic histopathological analysis showed that the increased islet amount, the enlarged islet area, and the lipid accumulation in the pancreas were reversed by FF16 treatment in both IRF mice and KKAy mice. In the palmitate-induced RINm5f cell model, FF16 could effectively reduce the apoptosis and enhance the glucose-stimulated insulin secretion, respectively. In conclusion, FF16 could improve the T2DM by protecting the pancreatic beta-cells.

UPLC-Q-Orbitrap-MS/MS-Guided Isolation of Bioactive Withanolides from the Fruits of Physalis angulata.

Physalis angulata Linn. is an exotic Amazonian fruit that is commonly recognized as wild tomato, winter cherry, and gooseberry. While its fruit is known to contain many nutrients, such as minerals, fibers, and vitamins, few papers have investigated withanolide derivatives from its fruits. UPLC-Q-Orbitrap-MS/MS, which produces fragmentation spectra, was applied for the first time to guide the isolation of bioactive withanolide derivatives from P. angulata fruits. As a result, twenty-six withanolide derivatives, including two novel 1,10-secowithanolides (1 and 2) and a new derivative (3), were obtained. Compounds 1 and 2 are rare rearranged 1,10-secowithanolides with a tetracyclic 7/6/6/5 ring system. All structures were assigned through various spectroscopic data and quantum chemical calculations. Nine withanolide derivatives exhibited significant inhibitory effects on three tumor cell lines with IC50 values of 0.51-13.79 µM. Moreover, three new compounds (1-3) exhibited potential nitric oxide inhibitory effects in lipopolysaccharide-stimulated RAW264.7 cells (IC50: 7.51-61.8 µM). This investigation indicated that fruits of P. angulata could be applied to treat and prevent cancer and inflammatory-related diseases due to their potent active withanolide derivatives.

Matrix metalloproteinase 2 of grass carp Ctenopharyngodon idella (CiMMP2) is involved in the immune response against bacterial infection.

The gene encoding matrix metalloproteinase 2 (MMP2) was cloned from grass carp (Ctenopharyngodon idella), and its expression levels during Aeromonas hydrophila infection and embryonic development stages were evaluated. The complete open reading frame of CiMMP2 was 1974 bp in length, encoding a 658-amino acid polypeptide. The deduced MMP2 protein contained four conserved domain structures, including an N-terminal signal sequence, a propeptide domain, three repeats of fibronectin-type II domain inserted in the catalytic domain and a C-terminal hemopexin-like domain. Phylogenetic analysis of MMP2s grouped grass carp with other teleosts. Detected in all fish tissues examined, CiMMP2 expression increased in the spleen and head kidney at 4 h and was significantly downregulated at 1 d after A. hydrophila infection. CiMMP2 transcripts were present in unfertilized eggs, suggesting its maternal origin. These findings implicate an important role for CiMMP2 in A. hydrophila-related diseases and early embryonic developmental stages of grass carp.

[A new fluorescence method for determination of sodium-glucose cotransporter 2 activity].

OBJECTIVE: To develop a new fluorescence method for the determination of human sodium glucose cotransporter 2 (SGLT2) activity. METHODS: Firstly full length human SGLT2 cDNA was cloned and the recombined plasmid pIRES2-EGFP-SGLT2 was constructed. Then the construct was subjected to restriction enzyme digestion analysis. In addition, SGLT2 insert clones were fully sequenced to confirm its nucleotide sequence, and then the recombined plasmid was transfected into HEK293 cells. The expression of green fluoresscent protein (GFP) was detected by confocal and flow cytometry (FCM), respectively. The protein expression of SGLT2 was determined by Western Blot assay. The transport activity of SGLT2 was determined by FCM choosing 2-NBDG as the detection target. RESULTS: Both restriction enzyme digestion and DNA sequencing assays showed that the recombined plasmid was constructed successfully. After transient transfection into HEK293 cells, the GFP expression analysis displayed high transfection efficiency and transcription activity, and the fluorescence intensity of the transfected cells was much higher than that of the untransfected cells (P<0.01). SGLT2 was more highly expressed in pIRES2-EGFP-SGLT2 transfected cells as compared with the empty vector (pIRES2-EGFP) transfected cells (P<0.05); the expression of SGLT2 in the untransfected cells was similar to that in the empty vector transfected cells. The Na(+) dependent 2-NBDG uptake was significantly increased in the transfected cells compared with that in the untransfected cells (P<0.01). CONCLUSION: A new fluorescence method for determination of SGLT2 activity has been developed with a eukaryotic expression vector of human SGLT2.

Genetic screening for hypertension and COVID-19 reveals functional variation of SPEG potentially associated with severe COVID-19 in women.

The coronavirus disease 2019 (COVID-19) pandemic, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has led to more than 6.4 million deaths worldwide. The prevalent comorbidity between hypertension and severe COVID-19 suggests common genetic factors may affect the outcome of both diseases. As both hypertension and severe COVID-19 demonstrate sex-biased prevalence, common genetic factors between the two diseases may display sex-biased differential associations. By evaluating COVID-19 association signals of 172-candidate hypertension single nucleotide polymorphisms (SNPs) derived from more than 1 million European individuals in two sex-stratified severe COVID-19 genome-wide association studies from UK BioBank with European ancestry, we revealed one functional cis expression quantitative trait locus of SPEG (rs12474050) showing sex-biased association with severe COVID-19 in women. The risk allele rs12474050*T associates with higher blood pressure. In our study, we found it is significantly correlated with lower SPEG expression in muscle-skeletal but with higher expression in both brain cerebellum and cerebellar hemisphere. Additionally, nominal significances were detected for the association between rs12474050*T and lower SPEG expression in both heart left ventricle and atrial appendage; among these tissues, the SPEG expression is nominally significantly higher in females than in males. Further analysis revealed SPEG is mainly expressed in cardiomyocytes in heart and is upregulated upon SARS-CoV-2 infection, with significantly higher upregulation of SPEG only observed in female but not in male COVID-19 patients compared to both normal female and male individuals, suggesting upregulation of SPEG is a female-specific protective mechanism against COVID-19 induced heart damage. Taken together, our analyses suggest the involvement of SPEG in both hypertension and severe COVID-19 in women, which provides new insights for sex-biased effect of severe COVID-19 in women.

Molecular cloning, characterization and expression patterns of HSP60 in the grass carp (Ctenopharyngodon idella).

HSP60 is a highly immunogenic molecule, which is able to activate a large number of T cell types and is implicated in a variety of autoimmune diseases. The grass carp (Ctenopharyngodon idella), a freshwater fish species of the family Cyprinidae, accounts for the third biggest value (USD 4.8 billion) at single species level of major cultured fish species in the world. Here, we isolated and characterized the HSP60 cDNA from grass carp (designated as CiHSP60). Its cDNA was 2434 bp in length and encoded a putative protein of 575 amino acids. BLAST analysis revealed that the CiHSP60 gene shared a high similarity with other known HSP60 sequences. CiHSP60 contained all three classical HSP60 family signatures. The mRNA of CiHSP60 was constitutively expressed in all tested tissues of untreated grass carp, including brain, muscle, trunk kidney, liver, head kidney, skin, spleen, heart, gill, intestine, and fin, with the highest expression level in the blood. CiHSP60 transcript was present in unfertilized eggs, which suggests that CiHSP60 transcription is maternally inherited. Fluorescent real-time quantitative RT-PCR was used to examine the expression of the CiHSP60 gene in grass carp after the challenge with the bacterium Aeromonas hydrophila. A clear time-dependent expression pattern of CiHSP60 was found after the bacterial challenge, and the mRNA expression reached a maximum level at three days post challenge, and returned to control levels after seven days. The upregulated mRNA expression of CiHSP60 in grass carp after bacterial challenge indicates that the HSP60 gene is inducible and involved in immune responses. These results suggest that CiHSP60 plays an important role in A. hydrophila-related diseases and in early embryonic development stages in grass carp.

NILs of Cold Tolerant Japonica Cultivar Exhibited New QTLs for Mineral Elements in Rice.

Chilling stress at booting stage can cause floret deterioration and sterility by limiting the supply of food chain and the accumulation of essential mineral elements resulting in reduction of yield and grain quality attributes in rice. Genomic selection of chilling tolerant rice with reference to the accumulation of mineral elements will have great potential to cope with malnutrition and food security in times of climate change. Therefore, a study was conducted to explore the genomic determinants of cold tolerance and mineral elements content in near-isogenic lines (NILs) of japonica rice subjected to chilling stress at flowering stage. Detailed morphological analysis followed by quantitative analysis of 17 mineral elements revealed that the content of phosphorus (P, 3,253 mg/kg) and potassium (K, 2,485 mg/kg) were highest while strontium (Sr, 0.26 mg/kg) and boron (B, 0.34 mg/kg) were lowest among the mineral elements. The correlation analysis revealed extremely positive correlation of phosphorus (P) and copper (Cu) with most of the cold tolerance traits. Among all the effective ear and the second leaf length correlation was significant with half of the mineral elements. As a result of comparative analysis, some QTLs (qBRCC-1, qBRCIC-2, qBRZC-6, qBRCHC-6, qBRMC-6, qBRCIC-6a, qBRCIC-6b, qBRCHC-6, and qBRMC-6) identified for calcium (Ca), zinc (Zn), chromium (Cr) and magnesium (Mg) on chromosome number 1, 2, and 6 while, a novel QTL (qBCPC-1) was identified on chromosome number 1 for P element only. These findings provided bases for the identification of candidate genes involved in mineral accumulation and cold tolerance in rice at booting stage.

Newly detected atrial fibrillation is associated with cortex-involved ischemic stroke.

BACKGROUND: Both cortical and cortical-subcortical (cortex-involved) lesions are typically associated with embolic stroke, of which atrial fibrillation (AF) is the common cause. The aim of this study was to find out the associations between cortex-involved stroke, vascular risk factors, and the subtypes (discovery time and duration) of AF. METHODS: This was an imaging study of the China Atrial Fibrillation Screening in Acute Ischemic Stroke Patients (CRIST) trial. Between October 2013 and June 2015, 1511 acute ischemic stroke or transient ischemic attack (TIA) patients within 7 days after stroke onset at 20 Chinese hospitals were enrolled in this prospective, multicenter cohort, cross-sectional study. The final analysis of this sub-study included 243 patients with AF with required magnetic resonance imaging (MRI) sequences. AF was diagnosed by 6-day Holter monitoring and classified by duration of 24 h. Two stroke specialists blinded to the clinical information reviewed MRI (diffusion-weighted MRI). The third stroke specialists, also blinded to the clinical information, assessed the conflicts. Adjusted large artery atherosclerosis as confounding factor, the associations between cortex-involved lesions, vascular risk factors, and the subtype of AF were evaluated by univariate and multivariate regression analyses. RESULTS: Of 243 acute ischemic stroke patients with AF, 190 were known AF and 53 were newly detected AF. There were 28 patients with AF persistent >24 h and 25 persistent ≤24 h in newly detected AF. Patients with newly detected AF were likely to have a fewer history of stroke or TIA (16.98% vs. 36.31%, P = 0.008) and lower fasting blood glucose (5.91 ±â€Š1.83 mmol/L vs. 6.75 ±â€Š3.83 mmol/L, P = 0.030) than patients with known AF. Among these 243 patients, 102 (41.98%) patients were with cortex-involved lesions. Cortex-involved lesions were significantly related to newly detected AF persistent >24 h (odds ratio [OR]: 4.517, 95% confidence interval [CI]: 1.490-13.696, P = 0.008), proteinuria (OR: 3.431, 95% CI: 1.530-7.692, P = 0.021), and glycosylated hemoglobin (OR: 0.632, 95% CI: 0.464-0.861, P = 0.004). CONCLUSIONS: Compared to previously known AF, newly detected AF persistent >24 h was associated with cortex-involved ischemic stroke. CLINICAL TRIAL REGISTRATION: NCT02156765, https://clinicaltrials.gov/ct2/show/record/NCT02156765.

Coevolution between human's anticancer activities and functional foods from crop origin center in the world.

Cancer is the leading cause of death around the world. Anticancer activities from many functional food sources have been reported in years, but correlation between cancer prevalence and types of food with anticancer activities from crop origin center in the world as well as food source with human migration are unclear. Hunger from food shortage is the cause of early human evolution from Africa to Asia and later into Eurasia. The richest functional foods are found in crop origin centers, housing about 70% in the world populations. Crop origin centers have lower cancer incidence and mortality in the world, especially Central Asia, Middle East, Southwest China, India and Ethiopia. Asia and Africa with the richest anticancer crops is not only the most important evolution base of humans and origin center of anticancer functional crop, but also is the lowest mortality and incidence of cancers in the world. Cancer prevention of early human migrations was associated with functional foods from crop origin centers, especially Asia with four centers and one subcenter of crop origin, accounting for 58% of the world population. These results reveal that coevolution between human's anticancer activities associated with functional foods for crop origin centers, especially in Asia and Africa.

A modified acid-fast staining method for rapid detection of Mycobacterium tuberculosis.

A modified acid-fast staining method was developed for rapid detection of Mycobacterium tuberculosis and its L forms, wherein carbol fuchsin and dioxogen were mixed into the sputum smear. With this method, the dyeing time is shortened and heating is not required. The sensitivity, specificity, positive predictive value, negative predictive value, positive rate, and diagnostic efficiency of the new method were compared to those obtained by PCR using 50 clinical samples. Further, 468 clinical samples were analyzed using the new method, the modified intensified Kinyoun (IK) acid-fast staining method, and the traditional Ziehl-Neelsen acid-fast staining method. Differences among the positive detection rates of the three methods were analyzed using Student's t-test, and no significant differences were found between the new method and the modified IK acid-fast staining method, while the rates of both these methods were higher than that of the traditional acid-fast staining method. Additionally, the dyeing time in the new method was markedly less than that in the modified IK acid-fast staining method (5 min and 24 h, respectively).

Induction of virus-neutralizing antibodies and T cell responses by dengue virus type 1 virus-like particles prepared from Pichia pastoris.

BACKGROUND: Dengue is currently a significant global health problem but no vaccines are available against the four dengue serotypes virus infections. The development of safe and effective vaccines has been hampered by the requirement of conferring complete protection against all four dengue serotypes and the lack of a convenient animal model. Virus-like particles (VLPs) have emerged as a promising subunit vaccine candidate. One strategy of vaccine development is to produce a tetravalent dengue subunit vaccine by mixing recombinant VLPs, corresponding to all four dengue virus serotypes. Towards this end, this study aimed to establish a Pichia pastoris (P. pastoris) expression system for production of dengue virus type 1 (DENV-1) VLPs and evaluate the humoral and cellular immune response of this particle in mice. METHODS: A recombinant yeast P. pastoris clone containing prM and E genes of DENV-1 was constructed and DENV-1 VLPs expressed by this clone were analyzed by sucrose density gradient centrifugation, Western blotting, and transmission electron microscope. Groups of mice were immunized by these particles plus adjuvant formulations, then mice were tested by ELISA and neutralization assay for humoral immune response, and by lymphocyte proliferation and cytokine production assays for a cellular immune response. RESULTS: Our data demonstrated that recombinant DENV-1 VLPs consisting of prM and E protein were successfully expressed in the yeast P. pastoris. Sera of VLPs immunized mice were shown to contain a high-titer of antibodies and the neutralization assay suggested that those antibodies neutralized virus infection in vitro. Data from the T lymphocyte proliferation assay showed proliferation of T cell, and ELISA found elevated secretion levels of interferon IFN-γ and IL-4. CONCLUSIONS: P. pastoris-expressed DENV-1 VLPs can induce virus neutralizing antibodies and T cell responses in immunized mice. Using P. pastoris to produce VLPs offers a promising and economic strategy for dengue virus vaccine development.

High-sensitivity C-reactive protein is a strong risk factor for death after acute ischemic stroke among Chinese.

BACKGROUND AND PURPOSE: Elevated plasma C-reactive protein (CRP) has been suggested as a risk factor for ischemic stroke (IS) and coronary ischemic disease. Evidence has shown that high-sensitivity CRP (hs-CRP) is related to a worsening prognosis after IS, but hs-CRP was rare in a large-sample study in a Chinese population. We investigated the associations between hs-CRP and outcome of Chinese patients after acute IS. METHODS: Seven hundred and forty-one consecutive acute IS patients (74.9% male, mean age 60.9 years), with baseline characteristics and hs-CRP measured within 24 h after hospitalization, were admitted in this study. We also prospectively followed up for clinical outcome and death 3 months after disease onset. hs-CRP was divided into two categories: hs-CRP >3 mg/L and hs-CRP ≤3 mg/L. Survival analysis using multivariable Cox regression was performed to analyze the association between hs-CRP and stroke outcomes after adjusting for potential confounding factors. RESULTS: Compared with low hs-CRP, patients with high hs-CRP (>3 mg/L) had a significantly higher rate of all-cause death (0.71% vs. 10.00%; P < 0.001) at 3 months after stroke onset. High hs-CRP was an independent risk factor for all-cause death (HR, 6.48; 95% CI, 1.41 to 29.8; P= 0.016), as well as history of atrial fibrillation (HR, 5.24; 95% CI, 1.83 to 15.0; P= 0.002), no statin therapy during hospitalization (HR, 4.56; 95% CI, 2.18 to 9.55; P < 0.001), high homocysteine (>15.1 mmol/L) (HR, 2.66; 95% CI, 1.26 to 5.60; P= 0.01); fasting glucose (>6.1 mmol/L) (HR, 9.14; 95% CI, 3.34 to 25.0; P < 0.001), NIHSS at admission (HR, 2.35; 95% CI, 1.35 to 4.09; P= 0.003) and history of coronary heart disease (CHD) (HR, 2.34; 95% CI, 1.06 to 5.17; P= 0.035). Kaplan-Meier survival curves showed a higher risk of death for patients with hs-CRP >3 mg/L (P= 0.016). CONCLUSION: Elevated plasma hs-CRP independently predicted risk of all-cause death within 3 months after acute IS in Chinese patients.