[Expressions of cysteine-rich secretory protein 2 in asthenospermia].

OBJECTIVE: To investigate the mRNA and protein expression levels of cysteine-rich secretory protein 2 (CRISP2) in the sperm of asthenospermia patients, and explore their relationship with sperm motility and related molecular mechanism. METHODS: We collected 78 semen samples from adult male patients with asthenospermia and another 70 from healthy volunteers as controls. We extracted total RNA and total protein from the sperm following purification of the sperm by Percoll gradient centrifugation, and detected the relative expressions of CRISP2 mRNA and protein in the two groups by RT-PCR, SYBR Green real-time PCR and Western blot. RESULTS: The expression of CRISP2 mRNA was down-regulated by 4.3 times and that of the CRISP2 protein by 1.71 times in the asthenospermia patients, significantly lower than in the normal control group (P < 0.05). CONCLUSION: The down-regulation of CRISP2 mRNA and protein expressions in the sperm of asthenospermia patients may be closely related with decreased sperm motility, which suggests that CRISP2 may serve as a potential molecular target for the research of asthenospermia.

[Differentially expressed genes in asthenospermia: a bioinformatics-based study].

OBJECTIVE: To study the differentially expressed genes in asthenospermia to gain a deeper insight into the molecular mechanisms of the disease. METHODS: We analyzed the differentially expressed genes in asthenospermia using GATHER, PANTHER and ToppGene online bioinformatics tools. RESULTS: Our bioinformatics mining and analyses revealed that the differentially expressed genes in asthenospermia played important roles in the cellular protein and macromolecular metabolism, protein modification, cell death, cell apoptosis and apoptosis induction. CONCLUSION: Asthenospermia patients experience a decline in sperm activity and the basic life activities of sperm simultaneously, and are also prone to cell apoptosis or death. Such differentially expressed genes as KIF3B, MYO15A, KIF6, KIF26B, KIF3A, DNHD2, DMN, DYNC2H1, STARD9, MYOHD1, and TPM1, which are involved in cytoskeletal structure, microtubule movement and cell movement, may be associated with asthenospermia, and therefore deserve further studies.

Fatal poisoning by accidental ingestion of the "heartbreak grass" (Gelsemium elegans) verified by toxicological and medico-legal analyses.

We present a case of fatal poisoning from accidental ingestion of Gelsemium elegans (G. elegans), a rarely toxic plant. A 41-year-old man was found dead, at his home, 6 h after drinking homemade herbal liqueur during lunch. Autopsy and routine toxicological analyses identified neither significant pathological findings nor routine poisons. However, a local botanist revealed that the homemade herbal liqueur contained G. elegans, a poisonous plant specific to Asia. To ascertain whether the decedent had ingested G. elegans, we performed liquid chromatography-mass spectrometry (LC-MS) and found two alkaloids (gelsemine and koumine) in his blood, gastric contents, as well as the suspected herbal liqueur. The cause of death was therefore confirmed to be G. elegans poisoning. Case reports of fatal poisoning due to ingestion of G. elegans are quite rare in English. Therefore, the present case broadens the scope on the possibility of death due to ingestion of G. elegans for forensic pathologists and toxicologists.

[Single- and two-layer gradient centrifugation in sperm separation: comparison and appraisal].

OBJECTIVE: To appraise the effect of single- and two-layer Percoll density gradient centrifugation in sperm separation. METHODS: Twenty semen specimens underwent single-(50%) and two-layer (90% and 45%) density gradient centrifugation, respectively. The sperm class analyzer (SCA) was used to analyze sperm density, motility and dynamic parameters and round cell density before and after the treatment. RESULTS: After separation, the sperm recovery rate of the single-layer method was (65.5 +/- 12.8)%, significantly higher than that of the two-layer method (P < 0.01). The percentages of grade a sperm of the single- and two-layer method were significantly higher than pre-treatment (P < 0.05, P < 0.01), that of the single-layer was significantly lower than that of the two-layer method (P < 0.05), but the percentage of grade c sperm of the former was significantly higher than that of the latter (P < 0.05). Compared with pre-treatment, the percentage of grade a + b sperm of the two-layer method was significantly higher (P < 0.05), while that of the single-layer method showed no significant difference (P > 0.05), and the round cell density of both the methods was significantly lower (P < 0.05, P < 0.01), with no significant differences between the two methods (P > 0.05). CONCLUSION: The single-layer method yields a higher rate of sperm recovery and causes little change in the sperm motility, while the two-layer method effects a lower rate and significantly improves sperm motility. Both the methods can efficiently separate sperm from round cells, and each has its own advantages and its application value in in vitro treatment of sperm.

[Update of asthenospermia-related genes and proteins].

One of the most common causes of male infertility is asthenospermia, whose pathogenesis, however, is not yet clear. Recent researches have found that some genes (such as tektin-2, DNAI1, DNAH5, DNAH11, AKAP4, SEPT4 and Smcp) and proteins (such as sperm proteins ACTB, ANXA5, PRM1, PRM2 and SABP and seminal proteins Tf, PSA, PAP and Fractalkine) are associated with asthenospermia. The finding of these molecular markers has provided a base for the explanation of the molecular mechanism of asthenospermia, and these markers may become the diagnostic and therapeutic targets of the disease.

[Literature-mining and bioinformatic analysis of androgen-independent prostate cancer-specific genes].

OBJECTIVE: To compare the differences of the gene expressions in androgen-independent and androgen-dependent prostate cancer (ADPC), gain a deeper insight into the molecular mechanism of androgen-independent prostate cancer (AIPC), and find effective means for its clinical diagnosis and treatment. METHODS: Eats of genes highly-associated with prostate cancer were obtained by mining PubMed with the FACTA tool, and the specifically expressed genes in AIPC were analyzed with a set of bioinformatic tools including GATHER, PANTHER, STRING and ToppGene. RESULTS: A total of 128 genes specifically expressed in AIPC were identified, as compared with 23 that were specific to ADPC. Bioinformatic analysis showed the essential roles of AIPC-specific genes in such important biological processes as cell signal transduction, cell adhesion, apoptosis, oncogenesis, cell proliferation and cell differentiation. CONCLUSION: Such genes as MMPJ, EGFR, MMP2, ADM, MIF, IGFBP3, 112, MET, BAD, RHOA, SPP1, EP300, SMAD3, RAE1, PTK2, and TGFB2 may play important roles in transforming ADPC into AIPC.

[Mutation of MTCYB and MTATP6 is associated with asthenospermia].

OBJECTIVE: To explore the correlation of the mutation of MTCYB and MTATP6 genes in sperm mitochondria with asthenospermia. METHODS: We extracted mtDNA from 80 semen samples of asthenospermia and 20 of normal sperm motility, amplified the MTCYB and MTATP6 genes by PCR, and analyzed their mutation by sequencing and BLAST matching. RESULTS: The deletion of both MTCYB and MTATP6 were detected in 20 of the 80 asthenospermia samples, MTCYB deletion in 16 and MTATP6 deletion in 4, accounting for 20% and 5% respectively. Sequencing and BLAST matching revealed G8887A mutation in the MTATP6 gene in the asthenospermia samples, with a mutation rate of 20%, while no regular mutation was noted in MTCYB. Neither significant deletion nor mutation was observed in any of the 20 samples of normal sperm motility. CONCLUSION: Both the deletion and mutation of MTCYB and MTATP6 genes in sperm mitochondria might affect sperm motility in adults.

[Research of the spermatozoal gene expression with gene microarrays].

OBJECTIVE: To perform the detection of spermatozoal gene expression in order to accelerate the study of spermatozoal molecular biology. METHODS: To collect the healthy adults sperm and lymphocytes respectively, and then to extract the total RNAs from them by RNeasy mini kit (QIAGEN) or Trizol reagent. Corresponding cDNAs were produced, digested, ligated, finally labeled with Cy3 (sperm) and CyS (lymphocyte) in the course of RD amplifying reactions. Hybridization with self-made microarrays contained 560 probes was carried out after the labeled cDNAs pured by PCR Product Purification Kit. RESULTS: Among the 560 probes, 72 genes were up-regulated, 321 genes were down-regulated, the others had no different expression. Furthermore, genes associated with replication, transcription, translation and regulative functions were non-different expression or down-regulated, and those belonged to the spermatogenesis associated, sperm associated antigen were up-regulated, but those involved in the glycolysis were up-regulated, in the oxidative phosphorylation were down-regulated. CONCLUSION: It had successfully confirmed that there were a plenty of genes expressed in sperm, furthermore the genes expressed were accorded to spermatozoal functions and characteristics.

[An initial examination of the spermatozoal gene expression profile].

OBJECTIVE: To collect the normal spermatozoal gene expression sequence tags with the restriction display technique for constructing a microarray to understand spermatozoal gene expression profiles. METHODS: The total RNA extracted from normal human spermatozoa were reversely transcribed into cDNAs, which were digested by Sau3AI and linked to universal adapters (adapter 1) at both ends. According to the sequence of the adapter, a pair of primers (universal primers 1) was designed, followed by PCR with primers 1 and the PCR products were transferred into E.coli. The positive clones were collected after identification to serve as the probes for constructing the gene expression microarray of spermatozoa by printing those probes on the slides. The accomplished microarrays were examined by Cy3-labeled normal spermatozoal samples. RESULTS: Altogether 1 859 probes were collected, from which 368 were picked out randomly for constructing the microarray. CONCLUSIONS: Human spermatozoa contain a rich repertoire of RNAs, and the probes we prepared possess good incredibility and speciality.

[Proliferation and denucleation of K562 cells induced by cytochalasin B].

OBJECTIVE: To observe the effect of cytochalasin B on the denucleation of K562 cells. METHODS: K562 cells were grown in RPMI 1640 medium supplemented with 10% calf serum and 4 microL cytochalasin B (CB). Denucleation was induced in the cultured cells by CB, and the cells were examined by phase contrast microscopy and Giemsa staining respectively. RESULTS: The denucleation of K562 cells induced by CB was clearly observed, and the cell proliferation was obviously inhibited. CONCLUSION: The denucleation efficiency of K562 cells is positively correlated with CB concentrations and the duration of CB treatment. CB at low doses may inhibit the cell proliferation and at high doses causes cell death.

Preliminary study of DNA microarray of human placenta gene expression profile.

OBJECTIVE: To prepare human placenta genechip for analyzing differential gene expressions. METHODS: The target gene amplified from Hybrid Hunter cDNA library was dotted onto the slides by the arrayer (PixSys 5500). Total RNA from K562 cells treated with or without arsenic trioxide was extracted, the mRNA purified and cDNA synthesized. Fluorescent labeling of the samples was performed by restriction display PCR, followed by hybridization with the microarray that was subsequently washed and scanned, with the derived signals analyzed by computer. RESULTS: A reliable and specific method for preparing and assessing gene expression profile microarray was established, with which a total of 45 differentially expressed gene fragments were isolated. CONCLUSION: The genechips can be helpful in the analysis of differential gene expressions.

[Analysis with DNA chips of the changes of gene expressions in K562 cells in response to As2O3 treatment].

OBJECTIVE: To investigate differential gene expression in apoptotic cells induced by As(2)O(3), and identify novel apoptosis-related genes. METHOD: Apoptosis of K562 cells cultured in RPMI 1640 medium supplemented with 10 % calf serum was induced by As(2)O(3). Total RNA of the apoptotic and normal cells were then extracted, purified and subject to reverse transcription into first-strand cDNA, labeled with Cy3/Cy5. Placenta DNA microarrays containing 348 DNA fragments were used to analyze the changes in gene expressions in the cells treated with As(2)O(3). RESULT: Eleven differentially expressed genes were identified in the apoptotic cells in comparison with the normal cells, 3 of which were associated with apoptosis, while the others were related to cell growth and proliferation. CONCLUSION: The placenta DNA microarrays we constructed may well apply to the analysis of the differentially expressed genes.

[Detection of cell apoptosis by MTT assay].

OBJECTIVE: To study the feasibility of using MTT assay to detect cell apoptosis. METHODS: K562 cells were grown in RPMI 1640 medium supplemented with 10% calf serum and 4 micromol/L arsenic trioxide. Apoptosis was induced in the cultured cells by As2O3, and the cells were detected with optical microscope, DNA gel electrophoresis and MTT staining respectively. RESULT: MTT staining could also accurately detect cell apoptosis, by which the apoptotic cells were easily distinguished from normal cells and dead cells. CONCLUSION: MTT staining is simple, convenient and practical for detecting cell apoptosis.

[Mining the specifically expressed genes in sperms based on the bioinformatics methods].

OBJECTIVE: To analyze the specifically expressed genes in sperms for better understanding of the molecular characteristics of sperms. METHODS: The hybridization data the genes in the sperms, oocytes and 10 normal tissues were retrieved from the GEO database to identify the genes expressed specifically in sperms and the patterns of their regulation using such bioinformatic tools as GATHER, PANTHER and DAVID. RESULTS AND CONCLUSIONS: Comparison of the spermatozoal gene expression profiles with those of the normal tissues identified 8998 differentially expressed probes, among which 25 genes were up-regulated by over 200 folds in the sperms. Comparison of the gene expression profiles between the oocytes and normal tissues resulted in the identification of 8981 differentially expressed probes. Of the 1709 up-regulated genes in the sperm with a ratio>5, 1218 genes showed similar expressions in the oocytes and the normal tissues, and 129 were up-regulated and 362 down-regulated in the oocytes. The 362 genes up-regulated in the sperms but down-regulated in the oocytes were involved mainly in protein modification and metabolism and nucleic acid metabolism, but very few participated in the intracellular signaling pathways. Numerous transcriptional factors containing the KRAB domain and receptor- independent serine/threonine kinase were specifically overexpressed in sperms, and the a very high proportion of the genes specifically overexpressed in the sperms coincided with the overexpressed genes in the neural stem cells and embryonic stem cells. The genes involved in the glycolysis were down-regulated in the sperms. These findings in the genes specifically expressed in the sperms by data mining using bioinformatic methods may provide better insight into the molecular characteristics of the sperms.

[Construction and preliminary identification of subtracted cDNA library of leukemia cell line K562].

OBJECTIVE: Subtractive hybridization technology is a common method to screen and clone differentially expressed genes. This study was to construct subtracted cDNA library of leukemia cell line K562, and screen for differentially expressed genes. METHODS: cDNA fragments of K562 cells (tester), prepared by restriction display (RD), were subtracted with the Sau3A I-digested cDNA fragments of normal lymphocytes (driver). The subtracted cDNA fragments were re-amplified, and cloned into pMD18-T vectors. Positive clones were selected by blue-white screening. The inserts in plasmid were amplified by polymerase chain reaction (PCR), and some of which were sequenced. RESULTS: The subtracted library contained 360 positive clones with cDNA fragments distributed mainly from 200 to 800 bp. The 50 randomly sequenced clones were derived from 42 known genes. CONCLUSION: Specific subtracted cDNA library of K562 cells was successfully constructed with reliable quality, and may be used to further screen and clone differentially expressed genes of K562 cells.

[Research advances on effect of arsenic trioxide on tumor].

Arsenic compounds are natural substances that have been used medically for more than 2,400 years in China. Since 1990s, Chinese physicians have began to use arsenic trioxide in treating the patients with acute promyelocytic leukemia (APL), and the results showed that arsenic trioxide was effective on APL patients. Further study of arsenic trioxide demonstrated that arsenic trioxide was safe and effective not only on patients with leukemia, but also on patients with many other kinds of malignant cancers. Arsenic trioxide exerted its anti-cancer effects mainly by inhibiting the cell growth and angiogenesis, inducing the cell partial cytodifferentiation and apoptosis, etc. In addition, this review looked forward to the prospect of application of gene chip, a newly developed and powerful technology in analysis of gene expression profile, in elucidation of the mechanism of arsenic trioxide on tumor.

[Analysis of gene expression patterns of leukemia K562 cells after cytochalasin B treatment].

BACKGROUND & OBJECTIVE: The advanced technique of DNA microarray makes it possible to monitor the expression of thousands of genes simultaneously in one hybridization experiment. This technique accelerates demonstration of anti-tumor drug mechanisms and discovery of new drug targets. This study was designed to investigate the differential gene expression of K562 cells after cytochalasin B treatment using cDNA microarray. METHODS: Restriction display polymerase chain reaction (RD-PCR) products of 277 human genes were spotted on a glass slide in microarray. K562 cells grew in RPMI 1640 medium with 10 microg/ml cytochalasin B. After 24 hours, the total RNA was isolated from K562 cells, and mRNA was purified. Both mRNA from the treated K562 cells and the controlled K562 cells were reversely transcribed into cDNA and labeled with two different fluorescence dyes: Cy5 or Cy3, using a method of restriction digestion and PCR labeling (RD-PCR). The probes were hybridized to the cDNA microarrays. After high-stringent washing,the cDNA microarray was scanned for the fluorescent signals and showed difference between the two cells. RESULTS: Among the 277 target genes, 18 down-regulated genes were identified after cytochalasin B treatment. CONCLUSION: There is a consistent tendency toward lower-expressed genes in partial K562 cells after cytochalasin B treatment. Most down-regulated genes were correlated with cell proliferation, signal transduction, and transcription factor.