几种CAM植物PEP羧化酶同工酶的比较研究

比较研究几种兼性和专一性ＣＡＭ植物材料的ＰＥＰＣ同工酶表明：经自然干旱诱导,兼性ＣＡＭ植物露花（Ｍｅｓｅｍｂｒｙａｎｔｈｅｍｕｍｃｏｒｄｉｆｏｌｉｕｍ）、长药景天（Ｓｕｄｕｍｓｐｅｃｔａｂｉｌｅ）有新的ＰＥＰＣ同工酶的出现,诱导前后各同工酶的天然分子量变化不大;而土三七（Ｓｅｄｕｍａｉｚｏｏｎ）则没有新的ＰＥＰＣ同工酶出现,但诱导后其同工酶的天然分子量有所增大。以上几种兼性ＣＡＭ植物的ＰＥＰＣ同工酶酶谱无明显昼夜变化。专一性ＣＡＭ植物的ＰＥＰＣ酶谱和天然分子量均较一致,亦无昼夜差异。     

Nanoscale mapping and organization analysis of target proteins on cancer cells from B-cell lymphoma patients

CD20, a membrane protein highly expressed on most B-cell lymphomas, is an effective target demonstrated in clinical practice for treating B-cell non-Hodgkin's lymphoma (NHL). Rituximab is a monoclonal antibody against CD20. In this work, we applied atomic force microscopy (AFM) to map the nanoscale distribution of CD20 molecules on the surface of cancer cells from clinical B-cell NHL patients under the assistance of ROR1 fluorescence recognition (ROR1 is a specific cell surface marker exclusively expressed on cancer cells). First, the ROR1 fluorescence labeling experiments showed that ROR1 was expressed on cancer cells from B-cell lymphoma patients, but not on normal cells from healthy volunteers. Next, under the guidance of ROR1 fluorescence, the rituximab-conjugated AFM tips were moved to cancer cells to image the cellular morphologies and detect the CD20-rituximab interactions on the cell surfaces. The distribution maps of CD20 on cancer cells were constructed by obtaining arrays of (16×16) force curves in local areas (500×500 nm²) on the cell surfaces. The experimental results provide a new approach to directly investigate the nanoscale distribution of target protein on single clinical cancer cells.     

B3GNT3 Expression Is a Novel Marker Correlated with Pelvic Lymph Node Metastasis and Poor Clinical Outcome in Early-Stage Cervical Cancer

Background

The β1,3-N-acetylglucosaminyltransferase-3 gene (B3GNT3) encodes a member of the B3GNT family that functions as the backbone structure of dimeric sialyl-Lewis A and is involved in L-selectin ligand biosynthesis, lymphocyte homing and lymphocyte trafficking. B3GNT3 has been implicated as an important element in the development of certain cancers. However, the characteristics of B3GNT3 in the development and progression of cancer remain largely unknown. Thus, our study aimed to investigate the expression pattern and the prognostic value of B3GNT3 in patients with early-stage cervical cancer.

Methods

The mRNA and protein levels of B3GNT3 expression were examined in eight cervical cancer cell lines and ten paired cervical cancer tumors, using real-time PCR and western blotting, respectively. Immunohistochemistry (IHC) was used to analyze B3GNT3 protein expression in paraffin-embedded tissues from 196 early-stage cervical cancer patients. Statistical analyses were applied to evaluate the association between B3GNT3 expression scores and clinical parameters, as well as patient survival.

Results

B3GNT3 expression was significantly upregulated in cervical cancer cell lines and lesions compared with normal cells and adjacent noncancerous cervical tissues. In the 196 cases of tested early-stage cervical cancer samples, the B3GNT3 protein level was positively correlated with high risk TYPES of human papillomavirus (HPV) infection (P = 0.026), FIGO stage (P < 0.001), tumor size (P = 0.025), tumor recurrence (P = 0.004), vital status (P < 0.001), concurrent chemotherapy and radiotherapy (P = 0.016), lymphovascular space involvement (P = 0.003) and most importantly, lymph node metastasis (P = 0.003). Patients with high B3GNT3 expression had a shorter overall survival (OS) and disease-free survival (DFS) compared with those with low expression of this protein. Multivariate analysis suggested that B3GNT3 expression is an independent prognostic indicator for cervical cancer patients.

Conclusions

Our study demonstrated that elevated B3GNT3 expression is associated with pelvic lymph node metastasis and poor outcome in early-stage cervical cancer patients. B3GNT3 may be a novel prognostic marker and therapeutic target for the treatment of cervical cancer.     

Removal of pentachlorophenol by immobilized horseradish peroxidase

Researches on the polymerization of aqueous pentachlorophenol (PCP) by the catalysis of horseradish peroxidase (HRP) with the existence of hydrogen peroxide (H₂O₂) were conducted. Factors, such as acidity, temperature, enzyme activity, and initial concentration of PCP and H₂O₂ that could influence the degradation were studied. Results showed that the optimum pH value for free enzyme was 5–6; relative higher temperature could accelerate the reaction greatly; PCP removal increased with an increase of enzyme concentration, and PCP (initial concentration 12.6 mg/L) removal percentage could reach nearly 70% under the highest enzyme concentration (about 0.05 u/ml) adopted in the experiment; removal percentage increased slightly with an increase of initial concentration of PCP, and when initial PCP concentrations were 13.0 and 0.7 mg/L, the removal percentages were about 73.7% and 35.7%, respectively; the molar ratio of the reaction between PCP and H₂O₂ was about 1:2.Based on the above results, researches on the removal of PCP by the immobilized HRP were conducted. The free HRP was immobilized on the polyacrylamide gel prepared by gamma-ray radiation method; then the immobilized HRP was filled into a column, and PCP was successfully removed by the immobilized HRP column. The results were compared with results using free HRP enzyme, which showed that the optimum pH value for the immobilized HRP is similar to that for the free HRP, and when pH=5.15, the immobilized HRP could reduce PCP with initial concentration 13.4 mg/L to the concentration of 4.9 mg/L within 1 h, and the immobilized HRP column could be used to repeatedly.     

Polymorphic variations in manganese superoxide dismutase (MnSOD), glutathione peroxidase-1 (GPX1), and catalase (CAT) contribute to elevated plasma triglyceride levels in Chinese patients with type 2 diabetes or diabetic cardiovascular disease

Manganese superoxide dismutase (MnSOD), glutathione peroxidase-1 (GPX1), and catalase (CAT) provide the primary antioxidant defense system. Impaired antioxidant defense increases oxidative stress and contributes to the development of type 2 diabetes and diabetic cardiovascular disease (CVD). We preformed a case-control study in Chinese type 2 diabetes patients, to determine if the MnSOD Val16Ala (T→C), GPX1 Pro198Leu (C→T), and CAT -262C/T (C→T) functional polymorphisms contribute to the development of type 2 diabetes or diabetic CVD. Patients with type 2 diabetes (n = 168) were divided into the non-CVD group (n = 83, >10 year since diagnosis) and CVD group (n = 85, history of ischemic CVD). Genotyping was performed using PCR-restriction fragment length polymorphism (PCR-RFLP) or PCR-based direct sequencing. The genotypic distribution in the non-CVD- and CVD-group and the clinical parameters in genotypic groups were not significantly different in the three polymorphic sites, respectively. Among eight genotypic combinations, the most common TT+CC+CC genotype (59.5%) was associated with higher triglyceride levels than the TT+CT+CC genotype, the second frequent one (14.9%; 1.77 ± 0.12 vs. 1.21 ± 0.11 mmol/l, P = 0.001), and all non-TT+CC+CC genotypes (40.5%; 1.77 ± 0.12 vs. 1.43 ± 0.12 mmol/l, P = 0.048). In the CVD group, significantly elevated triglyceride levels were also observed in patients with TT+CC+CC compared to patients with TT+CT+CC (2.00 ± 0.18 vs. 1.37 ± 0.16 mmol/l, P = 0.018) or non-TT+CC+CC genotypes (2.00 ± 0.18 vs. 1.65 ± 0.19 mmol/l, P = 0.070). The common MnSOD, GPX1, and CAT TT+CC+CC genotype may contribute to hypertriglyceridemia in Chinese patients with type 2 diabetes or diabetic CVD.     

A novel microfluidic immunoassay system based on electrochemical immunosensors: an application for the detection of NT-proBNP in whole blood

Electrochemical immunosensors have attracted great interest in the search for a selective, simple and reliable system for molecular recognition. Presently, electrochemical immunosensors have been widely studied for biomedical molecular's detection, but the regeneration of these immunosensors has restricted their wide application. To prepare a regeneration-free immunosensor, which may be more suitable for clinical determination, a repeatable immunoassay system was developed based on an electrochemical immunosensor with magnetic nanoparticles, biotin-avidin system (BAS) and Fab antibodies for the heart failure markers aminoterminal pro-brain natriuretic peptides (NT-proBNP). At the same time, a microfluidic system was combined into the proposed system, which enabled continuous determination. Using NT-proBNP as a model system, the proposed immunosensor exhibited rapid and sensitive amperometric response to NT-proBNP with good selectivity, stability, and a wide linear range (0.005-1.67 ng/mL and 1.67-4 ng/mL with a detection limit of 0.003 ng/mL under optimal conditions). Importantly, the proposed immunosensor was also suitable for the detection of other proteins and provided new opportunities for disease diagnosis.     

CCL3L1-CCR5 genotype improves the assessment of AIDS Risk in HIV-1-infected individuals

Background

Whether vexing clinical decision-making dilemmas can be partly addressed by recent advances in genomics is unclear. For example, when to initiate highly active antiretroviral therapy (HAART) during HIV-1 infection remains a clinical dilemma. This decision relies heavily on assessing AIDS risk based on the CD4⁺ T cell count and plasma viral load. However, the trajectories of these two laboratory markers are influenced, in part, by polymorphisms in CCR5, the major HIV coreceptor, and the gene copy number of CCL3L1, a potent CCR5 ligand and HIV-suppressive chemokine. Therefore, we determined whether accounting for both genetic and laboratory markers provided an improved means of assessing AIDS risk.

Methods and Findings

In a prospective, single-site, ethnically-mixed cohort of 1,132 HIV-positive subjects, we determined the AIDS risk conveyed by the laboratory and genetic markers separately and in combination. Subjects were assigned to a low, moderate or high genetic risk group (GRG) based on variations in CCL3L1 and CCR5. The predictive value of the CCL3L1-CCR5 GRGs, as estimated by likelihood ratios, was equivalent to that of the laboratory markers. GRG status also predicted AIDS development when the laboratory markers conveyed a contrary risk. Additionally, in two separate and large groups of HIV⁺ subjects from a natural history cohort, the results from additive risk-scoring systems and classification and regression tree (CART) analysis revealed that the laboratory and CCL3L1-CCR5 genetic markers together provided more prognostic information than either marker alone. Furthermore, GRGs independently predicted the time interval from seroconversion to CD4⁺ cell count thresholds used to guide HAART initiation.

Conclusions

The combination of the laboratory and genetic markers captures a broader spectrum of AIDS risk than either marker alone. By tracking a unique aspect of AIDS risk distinct from that captured by the laboratory parameters, CCL3L1-CCR5 genotypes may have utility in HIV clinical management. These findings illustrate how genomic information might be applied to achieve practical benefits of personalized medicine.     

Resource utilization conditions as biochar of an invasive plant Spartina alterniflora in coastal wetlands of China

Converting feedstocks of invasive plants into biochar is a new and cost‐effective measure for their control, and benefits for the sustainable development of native ecosystems. Spartina alterniflora, an invasive plant widely distributed in coastal wetlands of China, was used to produce biochar. We aimed to analyze how S. alterniflora biochar properties changed with desalination of feedstocks, pyrolysis temperature, and residence time. Results showed that desalting feedstocks increased biochar pH, stability, porosity, and surface area, but diminished biochar yield and polarity. Pyrolysis temperature positively affected biochar pH, surface area, and pore volume, while it had negative effects on biochar yield, oxygen and hydrogen contents, hydrogen/carbon and oxygen/carbon ratios, pore size, and function groups. However, residence time of pyrolysis had slight effects on biochar properties. The results are valuable for optimizing pyrolysis temperature and pretreatment measure of feedstocks, to tune S. alterniflora biochar properties for specific environmental usage.