A transcriptional landscape underlying sugar import for grain set in maize.

Developing seed depends on sugar supply for its growth and yield formation. Maize (Zea mays L.) produces the largest grains among cereals. However, there is a lack of holistic understanding of the transcriptional landscape of genes controlling sucrose transport to, and utilization within, maize grains. By performing in-depth data mining of spatio-temporal transcriptomes coupled with histological and heterologous functional analyses, we identified transporter genes specifically expressed in the maternal-filial interface, including (i) ZmSWEET11/13b in the placento-chalazal zone, where sucrose is exported into the apoplasmic space, and (ii) ZmSTP3, ZmSWEET3a/4c (monosaccharide transporters), ZmSUT1, and ZmSWEET11/13a (sucrose transporters) in the basal endosperm transfer cells for retrieval of apoplasmic sucrose or hexoses after hydrolysis by extracellular invertase. In the embryo and its surrounding regions, an embryo-localized ZmSUT4 and a cohort of ZmSWEETs were specifically expressed. Interestingly, drought repressed those ZmSWEETs likely exporting sucrose but enhanced the expression of most transporter genes for uptake of apoplasmic sugars. Importantly, this drought-induced fluctuation in gene expression was largely attenuated by an increased C supply via controlled pollination, indicating that the altered gene expression is conditioned by C availability. Based on the analyses above, we proposed a holistic model on the spatio-temporal expression of genes that likely govern sugar transport and utilization across maize maternal and endosperm and embryo tissues during the critical stage of grain set. Collectively, the findings represent an advancement towards a holistic understanding of the transcriptional landscape underlying post-phloem sugar transport in maize grain and indicate that the drought-induced changes in gene expression are attributable to low C status.

[Genetic testing and clinical analysis of a patient with Dilated cardiomyopathy due to variant of FLNC gene].

OBJECTIVE: To explore the genetic basis for a patient with Dilated cardiomyopathy. METHODS: A patient admitted to Beijing Anzhen Hospital Affiliated to Capital Medical University in April 2022 was selected as the study subject. Clinical data and family history of the patient was collected. Targeted exome sequencing was carried out. Candidate variant was verified by Sanger sequencing and bioinformatic analysis based on guidelines of the American College of Medical Genetics and Genomics (ACMG). RESULTS: DNA sequencing revealed that the patient has harbored a heterozygous c.5044dupG frameshift variant of the FLNC gene. Based on the ACMG guidelines, the variant was predicted to be likely pathogenic (PVS1+PM2_Supporting+PP4). CONCLUSION: The heterozygous c.5044dupG variant of the FLNC gene probably underlay the pathogenesis in this patient, which has provided a basis for the genetic counseling for his family.

Identification of transcription factors controlling cell wall invertase gene expression for reproductive development via bioinformatic and transgenic analyses.

Cell wall invertase (CWIN) hydrolyses sucrose into glucose and fructose in the extracellular matrix and plays crucial roles in assimilate partitioning and sugar signalling. However, the molecular regulators controlling CWIN gene transcription remain unknown. As the first step to address this issue, we performed bioinformatic and transgenic studies, which identified a cohort of transcription factors (TFs) modulating CWIN gene expression in Arabidopsis thaliana. Comprehensive bioinformatic analyses identified 18 TFs as putative regulators of the expression of AtCWIN2 and AtCWIN4 that are predominantly expressed in Arabidopsis reproductive organs. Among them, MYB21, ARF6, ARF8, AP3 and CRC were subsequently shown to be the most likely regulators of CWIN gene expression based on molecular characterization of the respective mutant of each candidate TF. More specifically, the obtained data indicate that ARF6, ARF8 and MYB21 regulate CWIN2 expression in the anthers and CWIN4 in nectaries, anthers and petals, whereas AP3 and CRC were determined primarily to regulate the transcriptional activity of CWIN4. TF-promoter interaction assays demonstrated that ARF6 and ARF8 directly control CWIN2 and CWIN4 transcription with AP3 activating CWIN4. The involvement of ARF8 in regulating CWIN4 expression was further supported by the finding that enhanced CWIN4 expression partially recovered the short silique phenotype displayed by the arf8-3 mutant. The identification of the five TFs regulating CWIN expression serves as a launching pad for future studies to dissect the upstream molecular network underpinning the transcription of CWINs and provides a new avenue, potentially, to engineer assimilate allocation and reproductive development for improving seed yield.

Archaic human remains from Hualongdong, China, and Middle Pleistocene human continuity and variation.

Middle to Late Pleistocene human evolution in East Asia has remained controversial regarding the extent of morphological continuity through archaic humans and to modern humans. Newly found ∼300,000-y-old human remains from Hualongdong (HLD), China, including a largely complete skull (HLD 6), share East Asian Middle Pleistocene (MPl) human traits of a low vault with a frontal keel (but no parietal sagittal keel or angular torus), a low and wide nasal aperture, a pronounced supraorbital torus (especially medially), a nonlevel nasal floor, and small or absent third molars. It lacks a malar incisure but has a large superior medial pterygoid tubercle. HLD 6 also exhibits a relatively flat superior face, a more vertical mandibular symphysis, a pronounced mental trigone, and simple occlusal morphology, foreshadowing modern human morphology. The HLD human fossils thus variably resemble other later MPl East Asian remains, but add to the overall variation in the sample. Their configurations, with those of other Middle and early Late Pleistocene East Asian remains, support archaic human regional continuity and provide a background to the subsequent archaic-to-modern human transition in the region.

Quality Evaluation of Taxilli Herba from Different Hosts Based on Simultaneous Determination of Multiple Bioactive Constituents Combined with Multivariate Statistical Analysis.

Taxilli Herba (TAXH) is an important traditional Chinese medicine with a long history, dating from the Eastern Han Dynasty to the present times. However, the active constituents in it that parasitize different hosts vary, affecting its clinical efficacy. Given the complexity of the host origins, evaluating the quality of TAXH is critical to ensure the safety and effectiveness of clinical medication. In the present study, a quantitative method based on ultra-fast liquid chromatography tandem triple quadrupole mass spectrometry (UFLC-QTRAP-MS/MS) was established, which simultaneously determined the content of 33 active constituents, including 12 flavonoids, 4 organic acids, 12 amino acids, and 5 nucleosides in 45 samples. Orthogonal partial least squares discriminant analysis (OPLS-DA) was employed to classify and distinguish between TAXH and its adulterants, Tolypanthi Herba (TOLH). A hierarchical clustering analysis (HCA) was conducted combined with a heatmap to visually observe the distribution regularity of 33 constituents in each sample. Furthermore, gray relational analysis (GRA) was applied to evaluate the quality of samples to get the optimal host. The results demonstrated that TAXH excelled TOLH in quality as a whole. The quality of TAXH parasitizing Morus alba was also better, while those that were parasitic on Cinnamomum camphora and Glyptostrobus pensilis had relatively poor quality. This study may provide comprehensive information that is necessary for quality control and supply a scientific basis for further exploring the quality formation mechanism of TAXH.

[Overview of metalomics research and its application prospect in mineral Chinese medicine research].

Metallomics is a frontier interdisciplinary subject at its vigorous development stage. Its goal is to systematically study the content, distribution, chemical species, structural characteristics and functions of metal elements in biological system. It is also a comprehensive discipline to study the existing state and function of free or complex metal elements in life. Metallomics is an ideal tool to study the biological behavior of inorganic elements, which can be used to solve many problems in the research of mineral Chinese medicine(MCM). It provides a strong theoretical basis and technical support for the research of MCM. Its theory and methods provide re-ference and enlightenment for the in-depth study of MCM, and also provide new ideas and open up new ways for the research of MCM. The application of metallomics theory and methods in the research of MCM is of great significance to reveal the material basis and mec-hanism of MCM, promote the process of basic research on MCM, fully exploit and utilize medicinal mineral resources and carry forward the traditional MCM treasure in China. In this paper, we introduced the concept, academic development, research content and research methods of metallomics, and discussed the application prospects of metallomics in the analysis of inorganic element composition characteristics and quality control, material basis and mechanism of MCM, so as to provide reference for further researches on MCM.

[Effects of mineral Chinese medicine Chloriti Lapis on contents of metal elements in plasma and lung tissue of acute exacerbation of chronic obstructive pulmonary disease(AECOPD) rats].

The effects of Chloriti Lapis on metal elements in plasma and lung tissue of acute exacerbation of chronic obstructive pulmonary disease( AECOPD) rats were studied. The rat AECOPD model with phlegm heat syndrome was established by smoking combined with Klebsiella pneumoniae infection. After the rats were treated by Chloriti Lapis,the contents of metal elements in plasma and lung tissue were determined by inductively coupled plasma-optical emission spectroscopy( ICP-OES) and inductively coupled plasma mass spectrometry( ICP-MS). The changes in the contents of metal elements were analyzed by SPSS 18. 0. Further,the correlations of differential metal elements( including Cu/Zn ratio) with differential metabolites in plasma,lung tissue and urine of AECOPD rats treated with Chloriti Lapis were analyzed. The results showed that Chloriti Lapis significantly up-regulated the contents of Fe,Al,Mn,Cu,Zn,Sn( P<0. 05),V,Co( P< 0. 01) and Cu/Zn ratio( P< 0. 05),and significantly down-regulated the contents of Ti( P< 0. 05)and Pb( P<0. 05) in the model rat plasma. It significantly increased the content of Be( P<0. 05) and decreased the contents of Mg,Ti and Al( P<0. 01) in model rat lung tissue. The element profiles of normal group,model group and Chloriti Lapis group can be well separated. Chloriti Lapis group and other groups were clustered into two categories. The taurine in plasma and phytosphingosine in lung tissue had the strongest correlations with differential metal elements. The Fe,Al,Mg,Be,Ti,V,Mn,Cu,Zn,Sn,and Co in Chloriti Lapis may directly or indirectly participate in the intervention of AECOPD rats. This group of metal elements may be the material basis of Chloriti Lapis acting on AECOPD rats,and reduce the Cu/Zn value in vivo. It was further confirmed that Chloriti Lapis could interfere with the metabolic pathways of taurine and hypotaurine in plasma and urine as well as the sphingolipid metabolism pathway in lung tissue of AECOPD rats. In addition,this study confirmed that long-term smoking can cause high-concentration Cd accumulation in the lung and damage the lung tissue.

[Metabonomics research on lung tissue of rats with acute exacerbation of chronic obstructive pulmonary disease treated with mineral Chinese medicine Chloriti Lapis].

To study the effect of mineral Chloriti Lapis on pulmonary metabolites and metabolic pathways in lung tissues of rats with acute exacerbation of chronic obstructive pulmonary disease(AECOPD). The AECOPD rat model of phlegm heat syndrome was replicated by the method of smoking combined with Klebsiella pneumoniae infection. Except for using UPLC-Q-TOF-MS analysis, SPSS 18.0, SIMCA 13.0 and other software were also used for statistical analysis. Through literature search and online database comparison, the differential metabolites were identified, and the possible metabolic pathways were analyzed. After 15 days of administration, PLS-DA analysis was carried out on lung tissue samples of rats in each group. The results showed that the metabolic profiles of lung tissues of rats in each group could be well separated, which indicated that Chloriti Lapis and aminophylline had significant intervention effect on the lung metabolic profile of rats with AECOPD. Moreover, the metabolic profile of Chloriti Lapis group was closer to that of control group, and the intervention effect was better than that of aminophylline group. As a result, 15 potential differential metabolites were identified: phytosphingosine, sphinganine, tetradecanoylcarnitine, L-palmitoylcarnitine, elaidic carnitine, lysoPC[18∶2(9Z,12Z)], lysoPC(16∶0), lysoPC[18∶1(9Z)], lysoPC(18∶0), stearic acid, lysoPC(15∶0), arachidonic acid, docosapentaenoic acid, linoleic acid and palmitic acid. Among them, Chloriti Lapis could significantly improve the levels of 10 differential metabolites of phytosphingosine, tetradecanoylcarnitine, L-palmitoylcarnitine, elaidic carnitine, lysoPC[18∶2(9Z,12Z)], lysoPC(16∶0), lysoPC[18∶1(9Z)], stearic acid, lysoPC(15∶0), and palmitic acid(P<0.05). The intervention effect of Chloriti Lapis group was better than that of aminophylline group. Analysis of metabolic pathways showed that there were 8 possible metabolic pathways that could be affected, and three of the most important metabolic pathways(pathway impact>0.1) were involved: linoleic acid metabolism, arachidonic acid metabolism, and sphingolipid metabolism. Chloriti Lapis had obvious intervention effects on lung tissue-related metabolites and metabolic pathways in rats with AECOPD, and the effect was better than that of aminophyllinne.

Development and validation of a prediction model (AHC) for early identification of refractory thrombotic thrombocytopenic purpura using nationally representative data.

Immune-mediated thrombotic thrombocytopenic purpura (iTTP) is a rare and life-threatening haematological emergency. Although therapeutic plasma exchange together with corticosteroids achieve successful outcomes, a considerable number of patients remain refractory to this treatment and require early initiation of intensive therapy. However, a method for the early identification of refractory iTTP is not available. To develop and validate a model for predicting the probability of refractory iTTP, a cohort of 265 consecutive iTTP patients from 17 large medical centres was retrospectively identified. The derivation cohort included 94 patients from 11 medical centres. For the validation cohort, we included 40 patients from the other six medical centres using geographical validation. An easy-to-use risk score system was generated, and its performance was assessed using internal and external validation cohorts. In the multivariable logistic analysis of the derivation cohort, three candidate predictors were entered into the final prediction model: age, haemoglobin and creatinine. The prediction model had an area under the curve of 0.886 (95% CI: 0.679-0.974) in the internal validation cohort and 0.862 (95% CI: 0.625-0.999) in the external validation cohort. The calibration plots showed a high agreement between the predicted and observed outcomes. In conclusion, we developed and validated a highly accurate prediction model for the early identification of refractory iTTP. It has the potential to guide tailored therapy and is a step towards more personalized medicine.

The Predictive Value of Red Cell Distribution Width and Red Cell Distribution Width to Erythrocyte Count Ratio for Adverse Cardiovascular Events During the Hospitalization of Patients of ST-segment Elevation Myocardial Infarction.

BACKGROUND: High red cell distribution width (RDW) is correlated with poor prognosis in acute coronary syndromes (ACS), including ST-segment elevation myocardial infarction (STEMI). However, the association of red cell distribution width to erythrocyte count ratio (RER) with STEMI undergoing percutaneous coronary intervention (PCI) during hospitalization has not been investigated. Therefore, we performed a retrospective study to investigate whether RER is associated with STEMI patients after PCI during hospitalization. METHODS: A total of 331 patients, who were hospitalized for STEMI and underwent PCI, were enrolled. Receiver operating characteristic curve (ROC) analyses were used to find the cutoff value of RER and classify the patients into two groups including higher RER group and lower RER group by cutoff value. Differences between measured parameters in higher RER and lower RER groups were analyzed by the Mann-Whitney U test. The evaluation correlation of RDW, red blood cell, and RER with major adverse cardiovascular events was determined by bivariate regression analysis. Univariate logistic regression analysis was used to determine the factors associated with adverse cardiovascular events during the hospitalization of STEMI patients. Multivariate logistic regression analysis was performed to evaluate the potential independent predictors of STEMI. RESULTS: According to ROC analysis, the cutoff value of RER and RDW is 3.10 and 13.9, the sensitivity is 51% and 35%, the specificity is 76% and 80%, respectively. RER showed improved diagnostic capacity compared to RDW in correlation with adverse cardiovascular events during hospitalization in STEMI patients (p < 0.001). Compared with the lower RER group, the incidence of adverse cardiovascular events in STEMI patients is elevated in the higher RER group (75% vs. 64.5%, p < 0.05). Bivariate regression analysis indicated that RER and RDW showed a good correlation with adverse cardiovascular events, and the difference was statistically significant (R = 0.10 p < 0.05 vs. R = 0.05 p < 0.05). Univariate logistic regression analysis showed that age, heart rate, left ventricular ejection fraction, hyperlipidemia, RDW, mean platelet volume, total cholesterol, and RER were correlated with the occurrence of adverse cardiovascular events during the hospitalization of STEMI patients (p < 0.05). Multivariate logistic regression analysis demonstrated that RER could be an independent predictor of adverse cardiovascular events in STEMI patients (B: 0.574, OR: 1.776, 95% CI: 1.043 ~ 3.023, p < 0.05). CONCLUSIONS: RER and RDW demonstrated good correlation with adverse cardiovascular events during hospitalization in STEMI patients. RER is a potential independent predictor of adverse cardiovascular events during hospitalization in STEMI patients.

The Relationship between Erythrocyte Sedimentation Rate and Erythrocyte Sedimentation/Red Blood Cell Ratio and Disease Activity in Systemic Lupus Erythematosus.

BACKGROUND: The treatment options of systemic lupus erythematosus (SLE) patients in active and inactive phases are very different clinically, and the prognosis of patients with active SLE is much worse than inactive patients. However, the present indicators for diagnosis of SLE in activity are limited and inefficient. METHODS: Three hundred thirty patients with SLE were included. All patients are classified as SLEDAI (systemic lupus erythematosus disease activity index) > 4 as active and SLEDAI ≤ 4 as inactive. The linear correlation between variables was assessed by Pearson's correlation analysis. The difference between parameters in active and inactive patients was evaluated by the Mann-Whitney U test. The evaluation capacity of erythrocyte sedimenta-tion/red blood cell (ERR) and red blood cell/albumin ratio (RAR) on SLE activity was determined by bivariate regression analysis. Sensitivity and specificity are assessed by receiver operating characteristic curve (ROC). RESULTS: Compared with the inactive SLE, ESR (52.97 ± 35.66 vs. 32.38 ± 29.16 p < 0.001), ERR (15.40 ± 12.41 vs. 8.19 ± 8.10 p < 0.001) and RAR (0.13 ± 0.10 vs. 0.11 ± 0.20 p = 0.038) are all elevated in active SLE (52.97 ± 35.66 vs. 32.38 ±2 9.16 p < 0.001). ERR shows better correlation than RAR with ESR (p < 0.001 vs. p = 0.911). Patients with active SLE exhibited higher SLEDAI than those with inactive SLE (8.67 ± 2.67 vs. 3.27 ± 1.36, p < 0.001). According to ROC analysis, when ESR levels > 58.5 and ERR levels > 13.18, the sensitivity is 37.6% and 45.2%, the specificity is 83.0% and 83.2%. CONCLUSIONS: ESR and ERR are potential indicators for diagnosis of active and inactive SLE.

Molecular and clinical analysis of Chinese patients with anaplastic lymphoma kinase (ALK)-rearranged non-small cell lung cancer.

Anaplastic lymphoma kinase (ALK) fusions have been recognized as a therapeutic target in non-small cell lung cancer (NSCLC). However, molecular signatures and clinical characteristics of the Chinese population with ALK-rearranged NSCLC are not well elucidated. In the present study, we carried out targeted next-generation sequencing on tissue and plasma ctDNA samples in 1688 patients with NSCLC. Overall, ALK fusions were detected in 70 patients (4.1%), and the frequencies of ALK fusions detected in tissue and plasma samples were 5.1% and 3.3%, respectively. Additionally, the prevalence of breakpoint locations for EML4-ALK fusions in ctDNA was significantly correlated with that in tumor tissues (R2  = .91, P = .045). According to age, the incidence rates of ALK fusions among young (age <45 years), middle-aged (between 45 and 70 years) and elderly (>70 years) patients were significantly different (P < .001). In 70 ALK-rearranged cases, coexistence of epidermal growth factor receptor (EGFR) alterations and ALK fusions was detected in 12 cases (17.1%) and EGFR mutations tended to coexist with non-EML4-ALK rearrangements. Notably, novel ALK fusion partners, including TRIM66, SWAP70, WNK3, ERC1, TCF12 and FBN1 were identified in the present study. Among EML4-ALK fusion variants, patients with variant V1 were younger than patients with variant V3 (P = .023), and TP53 mutations were more frequently concurrent with variant V3 compared with variant V1 (P = .009). In conclusion, these findings provide new insights into the molecular-clinical profiles of patients with ALK-rearranged NSCLC that may improve the treatment strategy of this population.

Polyphenols and Alkaloids in Byproducts of Longan Fruits (Dimocarpus Longan Lour.) and Their Bioactivities.

The longan industry produces a large amount of byproducts such as pericarp and seed, resulting in environmental pollution and resource wastage. The present study was performed to systematically evaluate functional components, i.e., polyphenols (phenolics and flavonoids) and alkaloids, in longan byproducts and their bioactivities, including antioxidant activities, nitrite scavenging activities in simulated gastric fluid and anti-hyperglycemic activities in vitro. Total phenolic and total flavonoid contents in pericarp were slightly higher than those in seeds, but seeds possessed higher alkaloid content than pericarp. Four polyphenolic substances, i.e., gallic acid, ethyl gallate, corilagin and ellagic acid, were identified and quantified using high-performance liquid chromatography. Among these polyphenolic components, corilagin was the major one in both pericarp and seed. Alkaloid extract in seed showed the highest DPPH radical scavenging activity and oxygen radical absorbance capacity. Nitrite scavenging activities were improved with extract concentration and reaction time increasing. Flavonoids in seed and alkaloids in pericarp had potential to be developed as anti-hyperglycemic agents. The research result was a good reference for exploring longan byproducts into various valuable health-care products.

Chemotherapy Near the End of Life for Chinese Patients with Solid Malignancies.

INTRODUCTION: There are increasing concerns about the negative impacts of chemotherapy near the end of life (EOL). There is discrepancy among different countries about its use, and little is known about the real-world situation in China. PATIENTS AND METHODS: This retrospective study was conducted at six representative hospitals across China. Adult decedents with a record of advanced solid cancer and palliative chemotherapy were consecutively screened from 2010 through 2014. The prevalence of EOL chemotherapy within the last 1 month of life was set as the primary outcome. The correlations among EOL chemotherapy, clinicopathological features, and overall survival (OS) were investigated. RESULTS: A total of 3,350 decedents who had had cancer were consecutively included; 2,098 (62.6%) were male and the median age was 56 years (range, 20-88). There were 177 (5.3%), 387 (11.6%), and 837 (25.0%) patients who received EOL chemotherapy within the last 2 weeks, 1 month, and 2 months of life, respectively. We identified inferior OS (median OS, 7.1 vs. 14.2 months; hazard ratio, 1.37; 95% confidence interval [CI], 1.23-1.53; p < .001), more intensive treatments (e.g., admitted to intensive care unit [ICU] in the last month of life, received cardiopulmonary resuscitation and invasive ventilation support), and hospital death (odds ratio, 1.53; 95% CI, 1.14-2.06; p = .005) among patients who received continued chemotherapy within the last month compared with those who did not. However, subgroup analyses indicated that receiving oral agents correlated with fewer ICU admissions and lower rates of in-hospital death. CONCLUSION: This study showed that EOL chemotherapy is commonly used in China. Intravenous chemotherapy at the EOL significantly correlated with poor outcomes and the role of oral anticancer agents warrants further investigation. The Oncologist 2017;22:53-60Implications for Practice: The role of chemotherapy toward the end of life (EOL) in patients with solid cancers is debatable. This article is believed to be the first to report the current prevalence of EOL chemotherapy in China. This study found that, compared with oral anticancer agents, intravenous chemotherapy at the EOL was significantly associated with poor outcomes. Therefore, the role of oral anticancer agents at the EOL stage deserves further investigation.

KRAS mutation-induced upregulation of PD-L1 mediates immune escape in human lung adenocarcinoma.

It was reported that PD-L1 expression was correlated with genetic alterations. Whether PD-L1 was regulated by mutant Kirsten rat sarcoma viral oncogene homolog (KRAS) in non-small-cell lung cancer (NSCLC) and the underlying molecular mechanism were largely unknown. In this study, we investigated the correlation between PD-L1 expression and KRAS mutation and the functional significance of PD-1/PD-L1 blockade in KRAS-mutant lung adenocarcinoma. We found that PD-L1 expression was associated with KRAS mutation both in the human lung adenocarcinoma cell lines and tissues. PD-L1 was up-regulated by KRAS mutation through p-ERK but not p-AKT signaling. We also found that KRAS-mediated up-regulation of PD-L1 induced the apoptosis of CD3-positive T cells which was reversed by anti-PD-1 antibody (Pembrolizumab) or ERK inhibitor. PD-1 blocker or ERK inhibitor could recover the anti-tumor immunity of T cells and decrease the survival rates of KRAS-mutant NSCLC cells in co-culture system in vitro. However, Pembrolizumab combined with ERK inhibitor did not show synergistic effect on killing tumor cells in co-culture system. Our study demonstrated that KRAS mutation could induce PD-L1 expression through p-ERK signaling in lung adenocarcinoma. Blockade of PD-1/PD-L1 pathway may be a promising therapeutic strategy for human KRAS-mutant lung adenocarcinoma.

Effects of Surface Charges on the Bactericide Activity of CdTe/ZnS Quantum Dots: A Cell Membrane Disruption Perspective.

The inhibitory effects of CdTe/ZnS quantum dots (QDs) modified with 3-mercaptopropionic acid (negatively charged) or cysteamine (positively charged) on the metabolic activity of Escherichia coli were investigated using biological microcalorimetry. Results show that the inhibitory ratio of positive QDs is higher than that of negative QDs. Transmission electron microscopy images indicate that QDs are prone to be adsorbed on the surface of E. coli. This condition disturbs the membrane structure and function of E. coli. Fluorescence anisotropy results demonstrate that positive QDs show a significant increase in the membrane fluidity of E. coli and dipalmitoylphosphatidylcholine (DPPC) model membrane. Furthermore, fluorescence anisotropy values of DPPC membrane in the gel phase decreased upon the addition of positive QDs. By contrast, anisotropy values in the liquid-crystalline phase are almost constant. The change in membrane fluidity is associated with the increased permeability of the membrane. Finally, the kinetics of dye leakage from liposomes demonstrate that the surface charge of QDs is crucial to the interaction between QDs and membrane.

[Mineral composition analysis and hemostatic effect of limonitum with different mineral genesis].

Models were established in mice with warfarin sodium method, and their bleeding time and hemostasis time were measured by tail cutting method and slide method respectively. Rats were administered for 15 consecutive days to measure their recalcification time, plasma viscosity, platelet adhesion rate, platelet aggregation rate and other blood indexes. As compared with the blank group, the bleeding time was prolonged in model groupn(P<0.05). As compared with the model group, the results showed that the positive vitamin K, the leaching type water decoction and the sediment type decoction could significantly shorten the bleeding time (P<0.01); positive vitamin K significantly (P<0.01) shortened clotting time, and the leaching type water decoction, the sediment type water decoction and the sediment type powder could also shorten the clotting time (P<0.05). As compared with blank group, low dose, medium dose of leaching type water decoction, medium dose of powder, high dose of sediment type decoction and low dose of drug residues could reduce plasma viscosity (P<0.05), and high dose of leaching powder and low dose of water decoction could significantly reduce (P<0.01) plasma viscosity. As compared with blank group, Limonitum leaching type decoction high dose group could significantly reduce the platelet adhesion rate (P<0.05), while sediment type water decoction could significantly increase the platelet adhesion rate (P<0.05); the high dose of leaching type water decoction, high dose of drug residues, low dose of leaching type powder and low dose of drug residues could decrease the platelet aggregation rate (P<0.05), while high dose of leaching type water decoction and high dose of the powder could increase the platelet aggregation rate (P<0.05). Analysis of mineral compositions was conducted by polarized light microscopy and X-ray diffraction (XRD). The results of the both methods showed that Limonitum mineral compositions contained goethite, quartz, and kaolinite, and sedimentary type also contained illite and albite. Sediment type of Limonitum showed better hemostatic effect, which may be related to the high content of goethite and illite.

[Intervention Study of Mineral Chinese Medicine Chloriti Lapis in PTZ-kindled Epileptic Rat].

Objective: To study the intervention effect of Chloriti Lapis in PTZ-kindled epileptic rat. Methods: Rats were kindled by pentylenetetrazol( PTZ),and successful kindled model were administered with drugs, then taken out the hippocampus of the brain. HE staining method was used to observe lesion in hippocampus, immunohistochemical method was used to test protein expression of nNOS, xanthine oxidase method was used to measure the activity of T-SOD, thiobarbituric acid method was used to measure the content of MDA,and phosphorus determination method was used to detect the activities of Na+,K+-ATPase and Ca2 +,Mg2 +-ATPase. Results: Each group of Chloriti Lapis( powder group, dregs group and decoction group) decreased the lesion grade, MDA content,nNOS protein expression, while increased the T-SOD activities, Na+,K+-ATPase and Ca2 +,Mg2 +-ATPase activities in the hippocampu of rats. Conclusion: Chloriti Lapis have antiepileptic effects, the mechanism may be related to increasing brain antioxidant activities, eliminating free radicals, protecting membrane function, maintaining dynamic balance of ion concentration in the braiofn rat, inhibiting brain abnormalities discharge, and ultimately achieve the goal of epilepsy treatment.

[Application of Thermogravimetric-Differential Scanning Calorimetry(TG-DSC)in Quality Control of Limonitum].

Objective: To control the quality of Limonitum by investigating the thermoanalysis curves. Methods: Analysis Limonitum samples from different origins by Thermogravimetric-Differential Scanning Calorimetry( TG-DSC),and the processed samples and fake samples were analyzed to compare the difference of them at the same time. Results: Thermal analysis curves showed that most of Limonitum samples had three weight loss steps in 30 ~ 1 000 ℃,and the process of dehydration weight loss of goethite was obviously in about309 ℃. There was a positive correlation between the weight loss rate of the second step and the content of iron. Conclusion: The Thermal analysis method can provide reference to the identification and quality control of Limonitum.

[Expression of SDF-1/CXCR4 in acute infarct myocardium after implantation of bone marrow mesenchymal stem cells in rats].

OBJECTIVE: To explore the role of stromal cell derived factor-1 (SDF-1)/CXCR4 axis in acute infarct myocardium after an implantation of bone marrow mesenchymal stem cells (MSCs) in rats. METHODS: The animals were anesthetized by an intraperitoneal injection of pentobarbital sodium. Left anterior thoracotomy through 3/4 intercostals region was performed and then left anterior descending coronary arteries were ligated for modeling acute myocardial infarction. The MSCs were injected into the area of acute infarct myocardium after a 10-minute ligation of left anterior descending coronary artery. The different concentration and expression of SDF-1/CXCR4 in the area of acute myocardial infarction and left ventricular function were analyzed. RESULTS: At day 28 post-transplantation, the vascular density in MSCs implant group were significantly higher than that in control group (P<0.05). And left ventricular function in MSCs implant group improved significantly than that in control group too (P<0.05). At the same time, the expressions of SDF-1 and CXCR4 in topical injection sites of infarct myocardium were significantly higher than those in control group (P<0.05). In MSCs implant group, the level of SDF-1/CXCR4 peaked at Day 1 post-transplantation and then it declined. CONCLUSIONS: After the implantation of MSCs into acute infarct myocardium, there is vascular regeneration and the level of SDF-1/CXCR4 increases so that left ventricular function improves. And the mechanism may be due to an up-regulation of SDF-1/CXCR4 axis.