Volatile terpenes - mediators of plant-to-plant communication.

Plants interact with other organisms employing volatile organic compounds (VOCs). The largest group of plant-released VOCs are terpenes, comprised of isoprene, monoterpenes, and sesquiterpenes. Mono- and sesquiterpenes are well-known communication compounds in plant-insect interactions, whereas the smallest, most commonly emitted terpene, isoprene, is rather assigned a function in combating abiotic stresses. Recently, it has become evident that different volatile terpenes also act as plant-to-plant signaling cues. Upon being perceived, specific volatile terpenes can sensitize distinct signaling pathways in receiver plant cells, which in turn trigger plant innate immune responses. This vastly extends the range of action of volatile terpenes, which not only protect plants from various biotic and abiotic stresses, but also convey information about environmental constraints within and between plants. As a result, plant-insect and plant-pathogen interactions, which are believed to influence each other through phytohormone crosstalk, are likely equally sensitive to reciprocal regulation via volatile terpene cues. Here, we review the current knowledge of terpenes as volatile semiochemicals and discuss why and how volatile terpenes make good signaling cues. We discuss how volatile terpenes may be perceived by plants, what are possible downstream signaling events in receiver plants, and how responses to different terpene cues might interact to orchestrate the net plant response to multiple stresses. Finally, we discuss how the signal can be further transmitted to the community level leading to a mutually beneficial community-scale response or distinct signaling with near kin.

Visible-Light-Induced Decarboxylative Cyclization of 2-Alkenylarylisocyanides with α-Oxocarboxylic Acids: Access to 2-Acylindoles.

An efficient and practical protocol for visible-light-induced decarboxylative cyclization of 2-alkenylarylisocyanides with α-oxocarboxylic acids has been developed, which afforded a broad range of 2-acylindoles in moderate to good yields. The reaction proceeds through a cascade of acyl radical addition/cyclization reactions under irradiation of an Ir3+ photoredox catalyst without external oxidants and features simple operation, scalability, a broad substrate scope, and good functional group tolerance.

An in vitro study of coagulation properties in refrigerated whole blood and reconstituted whole blood.

OBJECTIVE: Fresh whole blood (WB) has been used in military applications and cardiac surgery. We undertook a study of the coagulation properties of refrigerated WB stored for 21 days and compared them with the properties of reconstituted WB. STUDY DESIGN AND METHODS: Ten WB units were obtained from healthy volunteer donors and stored at 4 ± 2°C. Samples were obtained on Days 1, 2, 4, 6, 8, 10, 14 and 21 from the WB units. Ten units of reconstituted WB were prepared with a ratio of red cells, platelets and plasma of 1:1:1. Tests included complete blood count, electrolyte, routine coagulation, blood coagulation factor and thromboelastography. RESULTS: There was a progressive decline in Hb, WBC, PLT, sodium and coagulation factors but a progressive increase in APTT, PT and potassium in WB. The concentrations of factor (F)V and FVIII as well as FII and FX of WB were higher before Days 4, 2, 8 and 14, respectively, compared with the concentrations of reconstituted WB. The concentrations of FVII, FIX, FXI and FXII in WB were found to be equal to or higher than those in reconstituted WB throughout the course of 21 days. TEG variables in all WB units were normal throughout the course of 10 days. The mean PT and APTT of WB were lower than those of reconstituted WB before Days 14 and 10, respectively. CONCLUSION: This study suggests that the coagulation properties of refrigerated WB were equal to or superior to those of reconstituted WB for a minimum of 10 days.

A case of dispermic chimerism with normal phenotype identified during ABO blood grouping.

BACKGROUND: Human chimerism with normal phenotype derived from the fusion of two different zygotes is a rare phenomenon. We describe a case of a phenotypically normal 17-year-old diagnosed with dispermic chimerism during routine ABO blood grouping. METHODS: ABO grouping, ABO genotyping, karyotyping, human leukocyte antigen (HLA) typing, and short tandem repeat (STR) analysis were performed. RESULTS: Forward typing with anti-A and anti-B sera resulted in mixed-field agglutination of red blood cells. The mother and father were blood group O and AB, respectively. The proposita had O1, A201 and B alleles in the ABO locus; O1 was a maternal allele, while A201 and B were the paternal alleles. The proposita karyotype was 46,XX/46,XY. HLA typing revealed that the proposita had three alleles (46, 51, 54) at the HLA-B locus, with the additional allele of paternal origin. STR analysis identified three alleles for five of the 15 markers (D2S1338, TPOX, D8S1179, D19S433, and D21S11) analyzed in the proposita's blood- and skin fibroblast-derived DNA. The additional alleles of TPOX, D8S1179, and D21S11 were of paternal origin. CONCLUSIONS: The genetic findings suggest that this proposita was produced by dispermic fertilization of two identical haploid ova formed by parthenogenetic activation.

[Biological Effect of Microplastics with Different Functional Groups on the Bacterial Communities and Metabolic Functions of Zebrafish (Danio rerio) Embryos].

To investigate the influences of functional groups on the biological effects caused by microplastics, the accumulation of three polystyrene microplastics (PS, PS-NH2, and PS-COOH) in zebrafish (Danio rerio) embryos were analyzed, and then the responses of metabolic functions and microbial communities in zebrafish larvae were revealed using the combination of the microbiome and metabolome methods. The results showed that all microplastics could accumulate in zebrafish with concentrations ranging from 143 to 175 µg·g-1, and there were no significant differences in the accumulation potentials among different PS treatments. Exposure to plain PS significantly affected the metabolic capacity of aminoglycosides in zebrafish larvae, whereas the metabolic processes of amino acids were affected by PS-NH2. In the PS-COOH treatment, the metabolic pathways of the tricarboxylic acid cycle, amino acids, and glycolysis in zebrafish were markedly altered. The metabolic functions of zebrafish larvae were changed by all PS microplastics, resulting in toxic effects on zebrafish, and the functional group modification of microplastics may have further enhanced these toxicities. Compared to that in the control, exposure to PS-NH2 significantly reduced the diversity of microbial communities in zebrafish larvae and increased the proportion of Proteobacteria in the composition, leading to an imbalance of the bacterial community in zebrafish and thus disrupting the metabolic functions in the fish. Therefore, the functional modifications of microplastics may significantly alter the related stresses on aquatic organisms, leading to unpredictable ecological risks.

Polystyrene microplastics alter the trophic transfer and biotoxicity of fluoxetine in an aquatic food chain.

Microplastics (MPs) and fluoxetine are ubiquitous emerging pollutants in aquatic environments that may interact with each other due to the carrier effects of MPs, posing unpredictable risks to non-target organisms. However, limited studies have focused on the carrier effects of MPs in the aquatic food chain. This study evaluated the influences of polystyrene MPs on the trophic transfer and biotoxicity of fluoxetine in a simple food chain composed of brine shrimp (Artemia nauplii) and zebrafish (Danio rerio). The finding reveals that carrier effects of MPs enhanced the accumulation of waterborne fluoxetine in brine shrimp, but suppressed that in zebrafish due to the distinct retention times. The accumulated fluoxetine in shrimp was further transferred to fish through the food chain, which was alleviated by MPs due to their cleaning effects. In addition, the specific neurotransmission biotoxicity in fish induced by fluoxetine was mitigated by MPs, whilst the oxidative damage, apoptosis, and immune responses in zebrafish were reversely enhanced by MPs due to the stimulating effect. These findings highlight the alleviating effects of MPs on the trophic transfer and specific biotoxicity of fluoxetine in the food chain, providing new insights into the carrier effects of MPs in aquatic environments in the context of increasing global MP pollution.

Co-exposure of microplastics and sulfamethoxazole propagated antibiotic resistance genes in sediments by regulating the microbial carbon metabolism.

The concerns on the carriers of microplastics (MPs) on co-existing pollutants in aquatic environments are sharply rising in recent years. However, little is known about their interactions on the colonization of microbiota, especially for the spread of pathogens and antibiotic resistance genes (ARGs). Therefore, this study aimed to investigate the influences on the propagation of ARGs in sediments by the co-exposure of different MPs and sulfamethoxazole (SMX). The results showed that the presence of MPs significantly enhanced the contents of total organic carbon, while having no effects on the removal of SMX in sediments. Exposure to SMX and MPs obviously activated the microbial carbon utilization capacities based on the BIOLOG method. The propagation of ARGs in sediments was activated by SMX, which was further promoted by the presence of polylactic acid (PLA) MPs, but significantly lowered by the co-exposed polyethylene (PE) MPs. This apparent difference may be attributed to the distinct influence on the antibiotic efflux pumps of two MPs. Moreover, the propagation of ARGs may be also dominated by microbial carbon metabolism in sediments, especially through regulating the carbon sources of carboxylic acids, carbohydrates, and amino acids. This study provides new insights into the carrier effects of MPs in sediments.

Qihuang Zhuyu formula alleviates coronary microthrombosis by inhibiting PI3K/Akt/αIIbß3-mediated platelet activation.

BACKGROUND: Coronary microembolism (CME) is commonly seen in the peri-procedural period of Percutaneous Coronary Intervention (PCI), where local platelet activation and endothelial cell inflammation crosstalk may lead to micro thrombus erosion and rupture, with serious consequences. Qihuang Zhuyu Formula (QHZYF) is a Chinese herbal compound with high efficacy against coronary artery disease, but its antiplatelet mechanism is unclear. HYPOTHESIS/PURPOSE: This study aimed to elucidate the effects and mechanisms of QHZYF on sodium laurate-induced CME using network pharmacology and in vitro and in vivo experiments. METHODS: We employed high-performance liquid chromatography mass spectrometry to identify the main components of QHZYF. Network pharmacology analysis, molecular docking and surface plasmon resonance (SPR) were utilized to predict the primary active components, potential therapeutic targets, and intervention pathways mediating the effects of QHZYF on platelet activation. Next, we pretreated a sodium laurate-induced minimally invasive CME rat model with QHZYF. In vivo experiments were performed to examine cardiac function in rats, to locate coronary arteries on heart sections to observe internal microthrombi, to extract rat Platelet-rich plasma (PRP) for adhesion assays and CD62p and PAC-1 (ITGB3/ITGA2B) flow assays, and to measure platelet-associated protein expression in PRP. In vitro clot retraction and Co-culture of HUVECs with PRP were performed and the gene pathway was validated through flow cytometry and immunofluorescence. RESULTS: Combining UPLC-Q-TOF/MS technology and database mining, 78 compounds were finally screened as the putative and representative compounds of QHZYF, with 75 crossover genes associated with CME. QHZYF prevents CME mainly by regulating key pathways of the inflammation and platelets, including Lipid and atherosclerosis, Fluid shear stress, platelet activation, and PI3K-Akt signaling pathways. Five molecules including Calyson, Oroxin A, Protosappanin A,Kaempferol and Geniposide were screened and subjected to molecular docking and SPR validation in combination with Lipinski rules (Rule of 5, Ro5). In vivo experiments showed that QHZYF not only improved myocardial injury but also inhibited formation of coronary microthrombi. QHZYF inhibited platelet activation by downregulating expression of CD62p receptor and platelet membrane protein αIIbß3 and reduced the release of von Willebrand Factor (vWF), Ca2+ particles and inflammatory factor IL-6. Further analysis revealed that QHZYF inhibited the activation of integrin αIIbß3, via modulating the PI3K/Akt pathways. In in vitro experiments, QHZYF independently inhibited platelet clot retraction. Upon LPS induction, the activation of platelet membrane protein ITGB3 was inhibited via the PI3K/Akt pathway, revealing an important mechanism for attenuating coronary microthrombosis. We performed mechanistic validation using PI3K inhibitor LY294002 and Akt inhibitor MK-2206 to show that QHZYF inhibited platelet membrane protein activation and inflammation to improved coronary microvessel embolism by regulating PI3K/Akt/αIIbß3 pathways, mainly by inhibiting PI3K and Akt phosphorylation. CONCLUSION: QHZYF interferes with coronary microthrombosis through inhibition of platelet adhesion, activation and inflammatory crosstalk, thus has potential in clinical anti-platelet applications. Calyson, Oroxin A, Protosappanin A, Kaempferol and Geniposide may be the major active ingredient groups of QHZYF that alleviate coronary microthrombosis.

Rapid screening of illegally added drugs in functional food using a miniature ion trap mass spectrometer.

With the expansion of the functional food market, the qualification assessment of these products has become a major challenge, and efficient analytical tools are urgently needed. Here, a miniature mass spectrometer (MS) with self-aspiration capillary electrospray ionization (SACESI) source and ion trap analyzer was developed for rapid screening of various illegally added drugs in functional foods. No chromatographic separation was required, but a simplified two-step pretreatment method was developed to reduce the operational procedures and time consumption of the entire analysis. SACESI source uses capillary action to drive solution injection, which utilizes a simple structure and convenient operation to constitute a kind of disposable MS detection solution. To achieve accurate and automatic identification, an intelligent recognition algorithm with steps of spectrum preprocessing, characteristic peak matching, and support vector machine learning was constructed. The relative accuracy of rapid screening of 31 suspicious drugs in various samples is up to 99.78%. It achieves 100% correct identification for the 55 batches of actual samples captured by on-site inspection, which demonstrates the feasibility of the proposed analytical system and strategy in food safety applications.

Mycorrhiza-Tree-Herbivore Interactions: Alterations in Poplar Metabolome and Volatilome.

Plants are continuously interacting with other organisms to optimize their performance in a changing environment. Mycorrhization is known to affect the plant growth and nutrient status, but it also can lead to adjusted plant defense and alter interactions with other trophic levels. Here, we studied the effect of Laccaria bicolor-mycorrhization on the poplar (Populus x canescens) metabolome and volatilome on trees with and without a poplar leaf beetle (Chrysomela populi) infestation. We analyzed the leaf and root metabolomes employing liquid chromatography-mass spectrometry, and the leaf volatilome employing headspace sorptive extraction combined with gas-chromatography-mass spectrometry. Mycorrhization caused distinct metabolic adjustments in roots, young/infested leaves and old/not directly infested leaves. Mycorrhization adjusted the lipid composition, the abundance of peptides and, especially upon herbivory, the level of various phenolic compounds. The greatest change in leaf volatile organic compound (VOC) emissions occurred four to eight days following the beetle infestation. Together, these results prove that mycorrhization affects the whole plant metabolome and may influence poplar aboveground interactions. The herbivores and the mycorrhizal fungi interact with each other indirectly through a common host plant, a result that emphasizes the importance of community approach in chemical ecology.

Preparation of Three-Dimensional Porous Graphene by Hydrothermal and Chemical Reduction with Ascorbic Acid and its Electrochemical Properties.

Three-dimensional porous graphene (3D-PG) has attracted much attention due to its excellent electrochemical performance. Chemical reduction is one of common methods for preparing porous graphene. In order to develop a green and facile method for preparing three-dimensional porous graphene, in this paper, 3D-PG was fabricated by reduction of graphene oxide (GO) with ascorbic acid (AA) as reductant in hydrothermal condition based on non-toxic, non-flammable and mild reducing performance of ascorbic acid. It was found that the size and distribution of pores could be controlled by the reduction time and the concentration of AA in the solution. The pore sizes in R0, R1 and R2 were in the range of 0.5-1 µm, 1-1.5 µm, and 1.5-3 µm, respectively. It was found that the average pore size and volume increased along with the amount of reductants. Under optimal conditions - a reaction time of 20 h and a ratio of GO to AA=1 : 1 - the CV area of the so-obtained sample R1-20 at 100 mV was 0.06 and the specific capacitance of the 3D-PG electrode reaches 153.5 F ⋅ g-1 , which is suitable for use in supercapacitors.

Silver-Catalyzed Decarboxylative Allylation of Difluoroarylacetic Acids with Allyl Sulfones in Water.

A practical silver-catalyzed decarboxylative allylation of α,α-difluoroarylacetic acids with allyl sulfones is described, which provides a variety of ß,ß-difluorinated alkenes in good yields. Notably, the reaction proceeds smoothly in water with good functional group tolerance. The practicality and synthetic value of this process was demonstrated by scaled-up experiment and elaboration of the products via reduction or Heck reaction. Primary mechanism investigations suggest that a radical process might be involved.

Molecular prenatal diagnosis in 2 pregnancies at risk for spondyloepiphyseal dysplasia congenita.

BACKGROUND: Spondyloepiphyseal dysplasia congenita (SEDC) is an autosomal dominant skeletal dysplasia characterized by short stature, abnormal epiphyses, and flattened vertebral bodies. Secondary prevention of SEDC can be achieved by prenatal diagnosis. Reports of antenatally-diagnosed SEDC fetuses have been very rare and molecular prenatal diagnosis even rarer. We previously reported a familial G504S mutation in the type II collagen (COL2A1) gene resulting in SEDC. In this study, molecular prenatal diagnosis was performed to 2 couples in this family with pregnancies at risk for SEDC. METHODS: Amniotic fluid was sampled by amniocentesis under ultrasound guidance at 19+3 and 18+6 weeks' gestation, respectively. Karyotype and molecular genetic analysis were performed on cultured amniotic fluid cells. Maternal cell contamination was excluded by short tandem repeat (STR) analysis. Direct DNA sequencing and DHPLC were conducted to detect the potential mutation in exon 23 of COL2A1 gene. Both women underwent serial sonograms because they insisted that the molecular diagnosis should be confirmed by another method, although they had been informed that mutation analysis is predictive of the disease. RESULTS: Karyotype of both fetuses was normal and molecular genetic analysis revealed that fetus 1 carried a G504S mutation in exon 23, while fetus 2 was normal. In case 1, femur length of the fetus was markedly below the 5th centile at 23 weeks' gestation, which confirms the accuracy of molecular diagnosis. A medical termination was carried out at 27+5 weeks' gestation and a male fetus with a relatively large head and short limbs was delivered. The fetal radiograph demonstrated a number of features, including generalised platyspondyly, absent ossification of the vertebral bodies in the cervical region and significant shortening of the long bones. The diagnosis of SEDC was thus confirmed clinically. Ultrasound monitoring of fetus 2 showed that its femur length was normal for gestational age at repeated scans, which was consistent with the molecular diagnosis. CONCLUSIONS: Molecular analysis allows early and accurate prenatal diagnosis for SEDC once mutation is known in a family. However, considering the poor genotype/phenotype correlation in many cases of SEDC, the combination of ultrasound as well as molecular genetic approach might be needed.

[Coagulation Properties for Whole Blood Stored at 4℃].

OBJECTIVE: To study the coagulation properties the refrigerated whole blood stored at 4℃. METHODS: Ten units of whole blood were obtained from healthy volunteer donors and stored at 4±2℃ for 21 days. Samples were collected on the day after donation and on days 2, 4, 6, 8, 10, 14 and 21 for delection including complete blood count, electrolyte, APTT, PT, Fg, blood coagulation factors, and thromboelastography(TEG). RESULTS: The levels of Hb, WBC, Plt, sodium and potassium in each sample accorded with standard of storing whole blood. The level of Hb, WBC, Plt and Na+ decreased along with prolonging of storage time, while the K+ level increased along with prolonging of stored time, APTT and PT prolonged along with prolonging of thored time, PT>17 min at d 21, the Fg level change was no-obvious, The level of factor Ⅴ and Ⅷ decreased more than 50 % of baseline on d 6 and 4 respectively; the levels of factor Ⅱ, Ⅶ, Ⅸ, Ⅹ, Ⅺ, Ⅻ showed decreasing trend, but their levels were less than 40 % of baseline values at d 21. TEG test showed that no abnormalily of R value was found, the abnormal valnes of K and Angle were observed at d 21, the abnormal value of MA was observed at d 14. CONCLUSION: The whole blood stored for 10 days possesses normal coagulation function showing important significance for treatment of hemorrhage from war injury and surgical openation of heart and chest.

RNA sequencing enables systematic identification of platelet transcriptomic alterations in NSCLC patients.

Platelets are implicated as key players in the metastatic dissemination of tumor cells. Previous evidence demonstrated platelets retained cytoplasmic RNAs with physiologically activity, splicing pre-mRNA to mRNA and translating into functional proteins in response to external stimulation. Recently, platelets gene profile of healthy or diseased individuals were characterized with the help of RNA sequencing (RNA-Seq) in some studies, leading to new insights into the mechanisms underlying disease pathogenesis. In this study, we performed RNA-seq in platelets from 7 healthy individuals and 15 non-small cell lung cancer (NSCLC) patients. Our data revealed a subset of near universal differently expressed gene (DEG) profiles in platelets of metastatic NSCLC compared to healthy individuals, including 626 up-regulated RNAs (mRNAs and ncRNAs) and 1497 down-regulated genes. The significant over-expressed genes showed enrichment in focal adhesion, platelets activation, gap junction and adherens junction pathways. The DEGs also included previously reported tumor-related genes such as PDGFR, VEGF, EGF, etc., verifying the consistence and significance of platelet RNA-Seq in oncology study. We also validated several up-regulated DEGs involved in tumor cell-induced platelet aggregation (TCIPA) and tumorigenesis. Additionally, transcriptomic comparison analyses of NSCLC subgroups were conducted. Between non-metastatic and metastatic NSCLC patients, 526 platelet DEGs were identified with the most altered expression. The outcomes from subgroup analysis between lung adenocarcinoma and lung squamous cell carcinoma demonstrated the diagnostic potential of platelet RNA-Seq on distinguishing tumor histological types.

Nonylphenol induces apoptosis of Jurkat cells by a caspase-8 dependent mechanism.

Nonylphenol is the final biodegradation product of nonylphenol polyethoxylates, which are widely used surfactants in domestic and industrial products. Although nonylphenol is well known as an endocrine disrupting chemical, its effects on cell death and the mechanisms responsible for these apoptotic effects remain unclear. In the present study, Jurkat cells were treated with 0.1, 1 and 10 microM nonylphenol for 12 and 24 h, respectively. Cell viability was assessed with a Cell Counting Kit. The effects of nonylphenol on apoptosis of Jurkat cells were determined by DNA fragmentation (DNA ladder), Hoechst33258, PI and Annexin V FITC/PI double staining. Changes in mitochondrial membrane potential were detected with JC-1 fluorescence. In addition, enzyme activity of caspase-8 was evaluated by flow cytometry. The results demonstrated that nonylphenol inhibited the proliferation and induced loss of mitochondrial membrane potential, caspase-8 activation, internucleosomal DNA fragmentation. Furthermore, a caspase-8 inhibitor, IETD-fmk, blocked loss of mitochondrial membrane potential and apoptosis. These findings suggested that nonylphenol induced apoptosis of Jurkat cells by caspase-8 dependent mechanisms.

Induction of apoptosis by recombinant soluble human TRAIL in Jurkat cells.

OBJECTIVE: To investigate the therapeutic potential of tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL), a member of the TNF superfamily, and to analyze TRAIL-induced apoptosis in Jurkat cells. METHODS: Expression of TRAIL receptors (DR4 and DR5) was detected by reverse transcriptase-polymerase chain reaction (RT-PCR). Cytotoxic effects were determined by colony formation assay and a cell counting kit. The effects of recombinant TRAIL on apoptosis of Jurkat cells were determined by DNA fragmentation (DNA ladder) and PI staining. Changes in mitochondrial membrane potential were detected with JC-1 fluorescence. RESULTS: TRAIL inhibited the proliferation and induced internucleosomal DNA fragmentation (characteristic of apoptosis) and loss of mitochondrial membrane potential. CONCLUSION: Recombinant soluble TRAIL can be used as a therapy for cancer.

[Cloning, expression and purification of human TNF-related apoptosis-inducing ligand in Escherichia coli].

OBJECTIVE: To clone human tumor necrosis factor-related apoptosis-inducing ligand (TRAIL, 114-281) cDNA and develop an inducible system for expression in E. coli. METHODS: The human TRAIL (114-281) cDNA was amplified with the total RNA from the human peripheral blood monocytes by RT-PCR. The cDNA was inserted into pMD T vector. The selected integrants were confirmed by PCR screen, digestion with restriction enzymes and DNA sequencing. Then, the insert of human TRAIL cDNA was subcloned into prokaryotic expression vector pET28a. The construction of prokaryotic expression vector was proofed correct by RT-PCR and digestive identification. The recombinant protein was induced by IPTG (isopropyl-beta-D-thiogalactopyranoside) . The sTRAIL inclusion bodies were refolded by dilution method. Refolded protein was purified with column chromatography. RESULTS: Agarose gel electrophoresis of product of RT-PCR revealed a band around 500bp, which was expected. The positive integrants were confirmed by PCR screen and digestion with restriction enzymes. The same band as RT-PCR product was showed by PCR screen and digestion with restriction enzymes. Then the selected integrants were confirmed by DNA sequencing. The sequence was checked in GenBank. The construction of prokaryotic expression vector pET 28a was proofed correct by RT-PCR and digestive identification. TRAIL protein was successfully induced by IPTG in E. coli BL21. The results also showed that the protein was expressed as inclusion bodies. After the sTRAIL inclusion bodies were solubilized and refolded, the protein expressed was purified with one band, which was about 20kD, analyzed by SDS-PAGE. CONCLUSION: These results suggested that the hsTRAIL was cloned, expressed and purified in the present study. Significant quantities of TRAIL produced by this method should allow further studies in determining the physiological significance and function of TRAIL in the future.

[Scientific consideration and topic selection in the field of andrology].

The improvement of diagnosis and treatment of andrological disease depends on scientific advances in the corresponding domain of andrology. In this article, the author thought topic selection was of great significance for the improvement of diagnosis and treatment based on his clinical and scientific experience for years in the field of andrology. Topic selection should be closely combined with clinical practice and follow the principles of importance, innovation, feasibility and reality, which meets the demands of basic, therapeutic and epidemiologic aspects in andrology research. Several common approaches to topic selection were discussed as well in the article.

[Study on fetal SRY gene in maternal plasma using nested polymerase chain reaction].

OBJECTIVE: To develop a nested polymerase chain reaction (PCR) technique for fetal SRY gene identification using cell-free fetal DNA in maternal plasma. METHODS: Peripheral blood samples were obtained from 30 pregnant women and cell-free DNA was extracted by the phenol/chloroform method from plasma. The nested PCR was carried out to amplify the fragment of SRY gene by two sets of PCR primer pairs. Direct sequencing analysis was then performed on the PCR product. RESULTS: Among the 17 women bearing male fetuses, SRY sequences were detected in 15 plasma samples after nested PCR amplification, while none of the 13 women bearing female fetuses had the positive results. The accuracy and sensitivity were 93.3% (28/30) and 88.2% (15/17), respectively. CONCLUSION: The phenol/chloroform extraction for fetal DNA in maternal plasma was effective and simple. And the nested PCR amplification of SRY sequence is a convenient and low-cost approach for the non-invasive early prenatal diagnosis of sex-linked inheritant diseases.