Study of intermolecular interactions of piroxicam polymorphs / 药学学报

Piroxicam has polymorphism. Different crystalline forms can exhibit different physicochemical properties and biological activities. Analysis of the intermolecular interactions is essential to reveal the formation mechanism and differences of polymorphs. In this paper, Hirshfeld surface analysis and semi-empirical methods were used to calculate and analyze the intermolecular interactions in seven polymorphic forms of piroxicam. The results show that the Hirshfeld surface analysis method can clearly and intuitively reveal the intermolecular interactions, among which H…H, O…H/H…O and N…H/H…N interactions account for 95% of the total energy. There are differences in the proportion and distribution of the forces of different crystal forms. The energy calculation shows that the lattice energy of the hydrate is significantly lower than that of the anhydrous forms, and in the specific energy distribution, the contribution of the dispersion force is the most prominent. Further interaction energy analysis was found that within the distance of 3.8 Å from the center of the piroxicam molecule, different crystalline forms of piroxicam molecule have different interaction energies with surrounding molecules.

MeCP2 duplication causes hyperandrogenism by upregulating LHCGR and downregulating RORα.

Duplication of MECP2 (methyl-CpG-binding protein 2) gene causes a serious neurological and developmental disorder called MECP2 duplication syndrome (MDS), which is usually found in males. A previous clinical study reported that MDS patient has precocious puberty with hyperandrogenism, suggesting increased MeCP2 may cause male hyperandrogenism. Here we use an MDS mouse model and confirm that MECP2 duplication significantly upregulates androgen levels. We show for the first time that MeCP2 is highly expressed in the Leydig cells of testis, where androgen is synthesized. Mechanistically, MECP2 duplication increases androgen synthesis and decreases androgen to estrogen conversion through either the upregulation of luteinizing hormone receptor (LHCGR) in testis, as a result of MeCP2 binds to G-quadruplex structure of Lhcgr promoter and recruits the transcription activator CREB1 or the downregulation of the expression of aromatase in testis by binding the CpG island of Rorα, an upstream regulator of aromatase. Taken together, we demonstrate that MeCP2 plays an important role in androgen synthesis, supporting a novel non-CNS function of MeCP2 in the process of sex hormone synthesis.

Preparation, characterization and improved solubility of ticagrelor salts / 药学学报

Four salts of ticagrelor, ticagrelor-3,5-dinitrobenzoic acid, ticagrelor-pyrazinamide, ticagrelor-D-proline and ticagrelor-L-proline were prepared by solvent suspension and liquid-assisted grinding to improve the solubility of ticagrelor. The compounds were characterized by powder X-ray diffraction, Fourier transform infrared spectroscopy, differential scanning calorimetry, nuclear magnetic resonance spectroscopy, elemental analysis, and the intermolecular salt-bonding forces were analyzed. The equilibrium solubility of salts and pure drug in hydrochloride buffer pH 1.2 and phosphate buffer pH 6.8 were measured by high-performance liquid chromatography. Ticagrelor was salted with 3,5-dinitrobenzoic acid, pyrazinamide, D-proline, L-proline all in a stoichiometric ratio of 1∶1; with the exception of ticagrelor-D-proline, the solubility of the other three salts provided significantly improved solubility in hydrochloride buffer pH 1.2, and the equilibrium solubility of ticagrelor-3,5-dinitrobenzoic acid was increased by approximately 1.7 folds as compared to pure drug. Salt-forming technology is convenient and can improve the solubility of ticagrelor.

Novel mutations of AXIN2 identified in a Chinese Congenital Heart Disease Cohort.

Congenital heart defects (CHDs), the most common congenital human birth anomalies, involves complex genetic factors. Wnt/ß-catenin pathway is critical for cardiogenesis and proved to be associated with numerous congenital heart abnormities. AXIN2 has a unique role in Wnt/ß-catenin pathway, as it is not only an important inhibitor but also a direct target of Wnt/ß-catenin pathway. However, whether AXIN2 is associated with human CHDs has not been reported. In our present study, we found a differential expression of Axin2 mRNA during the development of mouse heart, indicating its importance in mouse cardiac development. Then using targeted next-generation sequencing, we found two novel case-specific rare mutations [c.28 C > T (p.L10F), c.395 A > G (p.K132R)] in the sequencing region of AXIN2. In vitro functional analysis suggested that L10F might be a loss-of-function mutation and K132R is a gain-of-function mutation. Both mutations disrupted Wnt/ß-catenin pathway and failed to rescue CHD phenotype caused by Axin2 knockdown in zebrafish model. Collectively, our study indicates that rare mutations in AXIN2 might contribute to the risk of human CHDs and a balanced canonical Wnt pathway is critical for cardiac development process. To our knowledge, it is the first study of AXIN2 mutations associated with human CHDs, providing new insights into CHD etiology.

MicroRNA-197 controls ADAM10 expression to mediate MeCP2's role in the differentiation of neuronal progenitors.

Duplication of MECP2 (Methyl-CpG-binding protein 2) causes severe mental illness called MECP2 duplication syndrome (MDS), yet the underlying mechanism remains elusive. Here we show, in Tg(MECP2) transgenic mouse brain or cultured neural progenitor cells (NPCs), that elevated MeCP2 expression promotes NPC differentiation into neurons. Ectopic expression of MeCP2 inhibits ADAM10 and thus the NOTCH pathway during NPC differentiation. In human cells, this downregulation on ADAM10 was mediated by miRNA-197, which is upregulated by MeCP2. Surprisingly, miR-197 binds to the ADAM10 3'-UTR via its 3' side, not the canonical seed sequence on the 5' side. In mouse cells, a noncoding RNA Gm28836 is used to replace the function of miR-197 between MeCP2 and ADAM10. Similar to MeCP2, overexpressing miR-197 also promotes NPCs differentiation into neurons. Interestingly, three rare missense mutations (H371R, E394K, and G428S) in MECP2, which we identified in a Han Chinese autism spectrum disorders (ASD) cohort showed loss-of-function effects in NPC differentiation assay. These mutations cannot upregulate miR-197. Overexpressing miR-197 together with these MeCP2 mutations could rescue the downregulation on ADAM10. Not only the inhibitor of miR-197 could reverse the effect of overexpressed MeCP2 on NPCs differentiation, but also overexpression of miR-197 could reverse the NPCs differentiation defects caused by MECP2 mutations. Our results revealed that a regulatory axis involving MeCP2, miR-197, ADAM10, and NOTCH signaling is critical for NPC differentiation, which is affected by both MeCP2 duplication and mutation.

Formate rescues neural tube defects caused by mutations in Slc25a32.

Periconceptional folic acid (FA) supplementation significantly reduces the prevalence of neural tube defects (NTDs). Unfortunately, some NTDs are FA resistant, and as such, NTDs remain a global public health concern. Previous studies have identified SLC25A32 as a mitochondrial folate transporter (MFT), which is capable of transferring tetrahydrofolate (THF) from cellular cytoplasm to the mitochondria in vitro. Herein, we show that gene trap inactivation of Slc25a32 (Mft) in mice induces NTDs that are folate (5-methyltetrahydrofolate, 5-mTHF) resistant yet are preventable by formate supplementation. Slc25a32gt/gt embryos die in utero with 100% penetrant cranial NTDs. 5-mTHF supplementation failed to promote normal neural tube closure (NTC) in mutant embryos, while formate supplementation enabled the majority (78%) of knockout embryos to complete NTC. A parallel genetic study in human subjects with NTDs identified biallelic loss of function SLC25A32 variants in a cranial NTD case. These data demonstrate that the loss of functional Slc25a32 results in cranial NTDs in mice and has also been observed in a human NTD patient.

Mild decrease in TBX20 promoter activity is a potentially protective factor against congenital heart defects in the Han Chinese population.

Congenital heart defects (CHDs) are one of the most common human birth defects worldwide. TBX20 is a crucial transcription factor for the development of embryonic cardiovascular system. Previous studies have demonstrated that mutations in the TBX20 coding region contribute to familial and sporadic CHD occurrence. However, it remains largely unknown whether variants in the TBX20 regulatory region are also related to CHDs. In this study, we sequenced the 2 kb region upstream of the TBX20 transcription start site in 228 CHD patients and 292 controls in a Han Chinese population. Among the 8 single nucleotide polymorphisms (SNPs) identified, six SNPs are in strong linkage disequilibrium and the minor alleles are associated with lower CHD risk (for rs10235849 chosen as tag SNP, p = 0.0069, OR (95% CI) = 0.68 (0.51-0.90)). Functional analysis showed that the minor alleles have lower transcriptional activity than major alleles in both human heart tissues and three cell lines. The electrophoretic mobility shift assay suggested that TBX20 minor alleles may exhibit higher binding affinity with certain transcription repressors. Our results indicate that a moderately lower TBX20 activity potentially reduces CHD risk in the Han Chinese population, providing new insight in the study of CHD etiology.

Weak power frequency magnetic field acting similarly to EGF stimulation, induces acute activations of the EGFR sensitive actin cytoskeleton motility in human amniotic cells.

In this article, we have examined the motility-related effects of weak power frequency magnetic fields (MFs) on the epidermal growth factor receptor (EGFR)-sensitive motility mechanism, including the F-actin cytoskeleton, growth of invasive protrusions and the levels of signal molecules in human amniotic epithelial (FL) cells. Without extracellular EGF stimulation, the field stimulated a large growth of new protrusions, especially filopodia and lamellipodia, an increased population of vinculin-associated focal adhesions. And, an obvious reduction of stress fiber content in cell centers was found, corresponding to larger cell surface areas and decreased efficiency of actin assembly of FL cells in vitro, which was associated with a decrease in overall F-actin content and special distributions. These effects were also associated with changes in protein content or distribution patterns of the EGFR downstream motility-related signaling molecules. All of these effects are similar to those following epidermal growth factor (EGF) stimulation of the cells and are time dependent. These results suggest that power frequency MF exposure acutely affects the migration/motility-related actin cytoskeleton reorganization that is regulated by the EGFR-cytoskeleton signaling pathway. Therefore, upon the MF exposure, cells are likely altered to be ready to transfer into a state of migration in response to the stimuli.

[Epidemiological and clinical features of occult hepatitis B in HIV infection without antiretroviral treatment].

OBJECTIVE: To investigate and analyze the differential prevalence, as well as the risk factors and clinical features, of occult hepatitis B virus (HBV) infection in the human immunodeficiency virus (HIV)-infected population without antiretroviral therapy (ART) as compared to the general (non-HIV-infected) population. METHODS: Two-hundred-and-forty-eight individuals with confirmed HIV infection but ART naive (males: 220, females: 28; 15-82 years old) were enrolled in the study, along with 121 healthy individuals (confirmed HIV antibody-negative; males: 53, females: 68; 20-88 years old). HBV markers (hepatitis B surface antigen (HBsAg); hepatitis B e antigen (HBeAg); anti-HBs, anti-HBe and anti-hepatitis B core (HBc) antibodies) were detected by microparticle enzyme-linked immunosorbent assay (AxSYM immunology analyzer manufactured by Abbott Laboratories); all cases and controls were confirmed negative for hepatitis B surface antigen (HBsAg). Then, the HBV DNA level in serum was detected using nucleic acid amplification assay (COBAS AmpliPrep/COBAS TaqMan HBV test, version 2.0 manufactured by Roche). CD4+ T lymphocytes were measured by flow cytometry, and alanine aminotransferase (ALT, marker of liver function) was measured by enzymatic assay. RESULTS: Twenty-four of the HIV cases (9.7%) and four of the healthy controls (3.3%) tested positive for HBV DNA; the amount of individuals with HBV DNA-positivity was significantly higher in the HIV-infected group (P = 0.035). Among the 24 cases of HBV DNA(+) HIV-infected individuals, the lowest HBV DNA load was < 20 IU/ml and the highest was 3.22 x 10s IU/ml; nine of the individuals (37.5%) had HBV DNA load > 100 IU/ml, four (16.7%) had 20-99 IU/ ml, and 11 (45.8%) had < 20 IU/ml. Among the total HIV-infected cases with HBV DNA-positivity, 7.3% (8/110) were anti-HBc(+)/anti-HBs(+), 20.8% (11/53) were anti-HBc(+)/anti-HBs(-), 14.3% (3/21) were anti-HBc(-)/anti-HBs(+), and 3.1% (2/64) were anti-HBc(-)/anti-HBs(-). The amount of individuals with HBV DNA-positivity in the anti-HBc(+)/anti-HBs(-) group was significantly different from those in the anti-HBc(+)/anti-HBs(+) group (P = 0.018) and the anti-HBc(-)/anti-HBs(-) group (P = 0.003). However, multiple comparison of HBV DNA loads detected between the four groups of HBV marker status revealed no significant difference (P = 0.805). Furthermore, statistical analysis provided no evidence to support that occult hepatitis B infection in HIV-infected individuals had any impact on CD4+ T lymphocytes count (Z = 1.902, P = 0.059) or ALT levels (Z =1.401, P = 0.161). CONCLUSION: HIV-infected individuals who are ART naive and HBsAg(-) have a higher incidence of HBV DNA-positivity than individuals in the general (non-HIV-infected) population. In addition, the highest rate of occult hepatitis B among the HIV-infected cases occurred among individuals who were anti-HBc(+)/anti-HBs(-).

A study in vitro on differentiation of bone marrow mesenchymal stem cells into endometrial epithelial cells in mice.

OBJECTIVE: To investigate the differentiation conditions of bone marrow mesenchymal stem cells (BMSCs) into endometrial epithelial cells and to confirm the effect of 17ß-estradiol in this process. STUDY DESIGN: BMSCs were cultured alone or co-cultured with endometrial stromal cells (EStCs) in control/differentiation medium (17ß-estradiol, growth factors) and were co-cultured with EStCs in different concentrations of 17ß-estradiol. Flow cytometry and immunocytochemistry were used to identify the isolated cells. Real-time RT-PCR and immunofluorescence were used to test the expression of epithelial cell markers. RESULTS: The epithelial markers cytokeratin-7, cytokeratin-18, cytokeratin-19, and epithelial membrane antigen were elevated in real-time RT-PCR (P<0.05), and cytokeratin was strongly positive in immunofluorescence analysis in the differentiated BMSCs. Cytokeratin-7 and cytokeratin-19 expression levels were highest in the 1 × 10⁻8 mol/L 17ß-estradiol group, as shown in real-time RT-PCR (P<0.05). CONCLUSION: BMSCs could be differentiated in the direction of endometrial epithelial cells in appropriate conditions in vitro: 17ß-estradiol may play a key role in stimulating BMSCs' epithelial differentiation in the process of endometriosis. CONDENSATION: Bone marrow mesenchymal stem cells can differentiate in the direction of endometrial epithelial cells in a certain microenvironment and appropriate concentration of 17ß-E2 can facilitate this differentiation.

[Markers of endothelial injury and plasma adipocytokine in antiretroviral-naive HIV patients].

OBJECTIVES: To investigate the markers of endothelial injury, adipocytokine and thrombotic activity and explore whether there are cardiovascular disease risk factors in antiretroviral-naive HIV patients. METHODS: Clinical data and venous blood samples were collected from 43 anti-retroviral naive HIV-infected patients during February-October 2009 in our center, and compared with 17 healthy subjects. Plasma leptin, adiponectin, soluble intercellular adhesion molecule-1 (sICAM-1), D-dimer were measured by ELISA. Four markers and cholesterol, triglyceride, fasting plasma glucose were compared between the two groups. The CD(4)(+)T cells and percentages of CD(38), HLA-DR on CD(8)(+)T were determined by flow cytometry and plasma HIV copies were detected with bDNA analyzer among HIV-infected participants. Spearman correlations between the significant markers and CD(4)(+) T cells, CD(8)(+) CD(38)(+)/CD(8)(+), CD(8)(+) HLA-DR(+)/CD(8)(+), HIV viral load were examined among HIV-infected participants. Analyses were conducted by using Stata version 7. RESULTS: Thirty-eight of the 43 patients were sexually infected by HIV and the median absolute CD(4)(+)T cell count was (133 ± 82) cells/µl, HIV RNA was (4.42 ± 0.66) lg copies/ml. HIV-infected patients, compared with healthy subjects, had lower leptin [11.41(7.91, 14.53) µg/L vs 55.31 (16.49, 229.65) µg/L, P = 0.0005], adiponectin [1.79 (1.40, 4.00) mg/L vs 3.36 (2.92, 4.18) mg/L, P = 0.003] and higher sICAM-1 [1.71(1.11, 2.40) mg/L vs 0.69 (0.57, 0.80) mg/L, P = 0.0000]. No significant differences exist in cholesterol, triglyceride, fasting plasma glucose. For HIV-infected participants, sICAM-1 tended to correlate with CD(8)(+)CD(38)(+)/CD(8)(+) and HIV viral load (r = 0.3378, P = 0.0267; r = 0.3904, P = 0.0096). CONCLUSION: Patients with untreated HIV infection have lower leptin, adiponectin and higher sICAM-1 levels and the relationship of these markers to HIV-mediated atherosclerotic risk requires further study.

[Long-term and stable expression of transgene mediated by piggyBac transposon in gynecological malignant tumor cells].

OBJECTIVE: To investigate the expression of exogenous gene transferred by piggyBac (PB) transposon in various gynecological malignant cell lines and reveal its potential application of gene therapy in gynecological cancer. METHODS: Amplified herpes simplex virus thymidine kinase (HSV-tk) gene coding region by PCR and integrated it into PB expression vector, PB[Act-RFP]DS, for reconstructing PB[Act-RFP, HSV-tk]DS (pPB/TK). By using different transfection reagents: FuGENE HD, jetPEI, lipofectamine 2000, pPB/TK together with helper plasmid Act-PBase were cotransfected into four mostly common gynecological malignant tumor cell lines HeLa, JEG-3, SKOV3 and HEC-1B. The mRFP1 report gene expressions was observed and detected by fluorescence microscope and flow cytometry to analyze transfection efficiency. The expressions of HSV-tk and mRFP1 gene were detected by reverse transcription PCR (RT-PCR). The cytotoxic effect of various concentration of pro-drug ganciclovir (GCV) for transfected cells was detected by methyl thiazole tetrazolium assay. The transfected cells were positive sorted by flow cytometry and limiting diluted to obtain the stable transfected cell line. The insertion sites of foreign gene transferred by PB transposon in genome were analyzed by inverse PCR. RESULTS: (1) Double digests analysis and sequences test demonstrated that pPB/TK vector was reconstructed successfully. (2) Using three different transfective reagents, PB transposon transferred HSV-tk gene and mRFP1 gene into HeLa, HEC-1B, SKOV3 and JEG-3 cell efficiently, and the transfection efficiency of pPB/TK for the same cell was different by using different transfective reagents; in Hela cell, the transfection efficiency of FuGENE HD [(78.7+/-9.2)%] was higher than that of lipofectamine 2000 [(54.1+/-11.4)%] and jetPEI [(46.5+/-7.4)%, all P<0.05]; using the same transfective reagent, the transfection efficiency of pPB/TK was also different on various cell lines, using FuGENE HD, the transfection efficiency of pPB/TK on HeLa, JEG-3 and SKOV3 cell was (78.7+/-9.2)%, (74.4+/-8.9)% and (83.2+/-9.7)% respectively, which all were higher than that on HEC-1B [(39.5+/-8.7)%, P<0.05]. (3) RT-PCR showed that there were the mRNA expression of HSV-tk and mRFP1 in all cell lines. (4) 50% inhibitory concentration of GCV for transfected cells, HeLa, JEG-3, SKOV3 and HEC-1B, was 1.29, 3.35, 0.09 and 13.28 microg/ml respectively. Inhibitory effect of GCV (10 microg/ml) on SKOV3 transfected with pPB/TK was (86+/-9)%, which was superior to that transfected with pORF-HSVtk alone [(52+/-12)%, P<0.05]. (5) The insertion sites of PB transposon in the target cells genome were located at TTAA sites. mRFP1 expression still could be detected in three months after transfected. CONCLUSIONS: PB transposon could transfer exogenous gene into various gynecological malignant cells, which could integrated into genome and obtain a long-term and stable expression. It is expected that PB transposon may supply a more efficient and safer transgene technology platform for gene therapy in gynecological cancer.

Follicle-stimulating hormone peptide can facilitate paclitaxel nanoparticles to target ovarian carcinoma in vivo.

Chemotherapy is an important treatment for ovarian cancer. However, conventional chemotherapy has inevitable drawbacks due to side effects from nonspecific biodistribution of the chemotherapeutic drugs. To solve such problem, targeted delivery approaches were developed. The targeted delivery approaches combine drug carriers with the targeting system and can preferentially bring drugs to the targeted sites. Follicle-stimulating hormone receptor (FSHR) is an ovarian cancer-specific receptor. By using a peptide derived from FSH (amino acids 33-53 of the FSH beta chain, named as FSH33), we developed a conjugated nanoparticle, FSH33-NP, to target FSHR in ovarian cancer. FSH33-NP was tested for recognition specificity and uptake efficiency on FSHR-expressing cells. Then, the antitumor efficiency of paclitaxel (PTX)-loaded FSH33-NP (FSH33-NP-PTX) was determined. FSH33-NP-PTX displayed stronger antiproliferation and antitumor effects compared with free PTX or naked PTX-loaded nanoparticles (NP-PTX) both in vitro and in vivo. In summary, this novel FSH33-NP delivery system showed very high selectivity and efficacy for FSHR-expressing tumor tissues. Therefore, it has good potential to become a new therapeutic approach for patients with ovarian cancer.

The piggyBac transposon is an integrating non-viral gene transfer vector that enhances the efficiency of GDEPT.

Gene-directed enzyme prodrug therapy (GDEPT) is a strategy developed to selectively target cancer cells. However, the clinical benefit is limited due to its poor gene transfer efficiency. To overcome this obstacle, we took advantage of piggyBac (PB) transposon, a natural non-viral gene vector that can induce stable chromosomal integration and persistent gene expression in vertebrate cells, including human cells. To determine whether the vector can also mediate stable gene expression in ovarian cancer cells, we constructed a PB transposon system that simultaneously expresses the Herpes simplex virus thymidine kinase (HSV-tk) gene and the monomeric red fluorescent protein (mRFP1) reporter gene. The recombinant plasmid, pPB/TK, was transfected into ovarian adenocarcinoma cells SKOV3 with FuGENE HD reagent, and the efficiency was given by the percentage of mRFP1-positive cells detected by flow cytometry and confocal microscopy. The specific expression of HSV-tk in transfected cells was confirmed by RT-PCR and western blotting. The sensitivity of transfected cells to pro-drug ganciclovir (GCV) was determined by methylthiazoletetrazolium (MTT) assay. A total of 56.4 +/- 8.4% cells transfected with pPB/TK were mRFP1 positive, compared to no measurable mRFP1 expression in pORF-HSVtk-transfected cells. The expression level of HSV-tk in pPB/TK-transfected cells was 10 times higher than in pORF-HSVtk-transfected cells. The results show that pPB/TK transfection increases the sensitivity of cells to GCV in a dose-dependent manner. Our data indicate that the PB transposon system could enhance the anti-tumor efficiency of GDEPT in ovarian cancer.

[A cross-sectional survey of occult hepatitis B virus infection in HIV-infected patients].

OBJECTIVES: Occult HBV infection is defined by positive HBV DNA in individuals with undetectable levels of HBsAg. The objective of this study was to assess the prevalence of occult HBV infection in HIV-infected patients. METHODS: Serum samples were obtained from 105 HBsAg-negative HIV patients who were hospitalized and were not given anti-virus treatment at Shanghai Public Health Clinical Center. Microparticle enzyme immunoassay (MEIA) was used to detect HBV serologic markers (HBsAg, anti-HBs, HBeAg, anti-HBe and anti-HBc). ELISA was used to detect HCV antibody. CD4+ T cell count was examined with flow cytometry. Nested PCR was used to amplify surface protein region of HBV. RESULTS: 32 (30.5%) patients (27 men, 5 women) were HBV DNA positive in the 105 HBsAg-negative HIV-infected patients (92 men and 13 women). 22 patients (including 5 patients with HBV DNA +) were in 16-30 years group, 44 patients (including 15 patients with HBV DNA +) were in 3149 years group and 39 patients (including 12 patients with HBV DNA +) were in 50-75 years group. 5 patients were negative for all HBV serologic markers and 27 patients detected with at least one of anti-HBc, anti-HBe or anti-HBs. 14 patients (29.8%) with HBV DNA + in 47 HIV-infected patients were coinfected with HCV, 18 patients (31.0%) were HBV DNA + in 58 HIV-monoinfected patients. The median absolute CD4+ T cell count was 145.1 cells/microl (4-623 cells/microl), 26 patients (34.7%) were HBV DNA + in 75 AIDS patients with CD4+ T cell <200 cells/microl and 6 patients (20.0%) HBV DNA + in 30 HIV-infected patients with CD4+ T cell >200 cells/microl. No statistical significant association could be established between the above factors. CONCLUSIONS: It is found that occult HBV did occur in HIV-infected patients. No statistical significant association could be established between occult HBV infection and gender, age, HBV serologic markers, coinfected HCV and CD4+ T cell count.

The effects of GABAergic neurotransmitters and GABAA receptors on the auditory afferent pathway in the brainstem analyzed by optical recording / 中国应用生理学杂志

<p><b>AIM</b>To explore the influence of GABAergic neurotransmitters and GABAA receptors on the auditory afferent impulses recorded in the brainstem evoked by electro-stimulation.</p><p><b>METHODS</b>Brainstem slices were prepared using ddy/ddy mice of postnatal 0-5th days. The brainstem slices were stained with a voltage-sensitive dye(NK3041). The cut end of the vestibulocochlear nerve (nVIIIth) connected with slices was stimulated by a tungsten electrode, a 16 x 16 pixels silicon photodiode array apparatus was used to record the optical mapping from auditory brainstem slices. The data were analyzed by ARGUS-50/PDA software.</p><p><b>RESULTS</b>The spatial-temporal patterns of the excitatory propagation from the vestibulocochlear nerve (nVIIIth) to cochlear nucleus and vestibular nucleus were displayed with multiple-sites optical recording. The optical signal coming from one pixel consisted of a fast spike-like response and a following slow response. Inhibitory neurotransmitter GABA decreased the fast spike-like response and following slow response of evoked optical signals, while an antagonist BMI against GABAA receptors increased the both responses.</p><p><b>CONCLUSION</b>A 16 x 16 pixel silicon photodiode array apparatus can be used to record multiple-sites optical mapping evoked by electro-stimulation to the cut end of the vestibulocochlear nerve. The every optical signal consists of both presynaptic and postsynaptic elements. Inhibitory neurotransmitter GABA and an antagonist BMI of GABAA receptors can modulate the excitatory propagation of evoked optical signals.</p>

Normal and modified urinary nucleosides represent novel biomarkers for colorectal cancer diagnosis and surgery monitoring.

BACKGROUND: Up to now, there is still no ideal tumor marker in early diagnosis and effective monitoring, especially for surgical resection of colorectal cancer (CRC). The aim of the present study was to evaluate the application of urinary normal and modified nucleosides in diagnosis and surgery monitoring of CRC. METHODS: Between October 2002 and July 2003, 52 consecutive patients with pathological confirmed CRC were enrolled. Spontaneous urine samples were collected 1 day before surgery and on day 8 postoperatively, and 14 urinary nucleosides were determined by reverse-phase high-performance liquid chromatography (RP-HPLC). Another 62 healthy people were also studied as control. The clinical routine tumor markers, serum carcinoembryonic antigen (CEA), carbohydrate antigen (CA)199, CA125, and alpha-fetoprotein (AFP) of CRC patients, were correspondingly evaluated by electrochemiluminescent immunoassay. RESULTS: The levels of 11 out of 14 of the determined urinary nucleosides in the CRC group were much higher than those of normal controls. Through the principal component analysis of these 14 nucleosides, 76.9% of CRC patients were correctly classified. The sensitivity of this analysis was much higher than that of CEA (38.5%), CA199 (40.4%), CA125 (15.4%), and AFP (17.3%; P < 0.01). Receiver operating characteristic (ROC) curve analysis of 1-methylguanosine (m1G) and pseudouridine (Pseu) showed good sensitivity-specificity profiles of the diagnosis of CRC. The elevated levels of the nine nucleosides significantly decreased after curative resection of 40 CRC cases. The data also showed that the preoperative levels of some nucleosides were positively related with tumor size and Dukes staging of CRC. CONCLUSION: The evaluation of normal and modified urinary nucleosides might become novel tumor markers, which will be facilitated in the clinical setting and helpful in the diagnosis, management and follow up of CRC. Pseu and m1G may be more promising for clinical use and be worthy of further studies in the near future.

Urinary nucleosides as biological markers for patients with colorectal cancer.

AIM: Fourteen urinary nucleosides, primary degradation products of tRNA, were evaluated to know the potential as biological markers for patients with colorectal cancer. METHODS: The concentrations of 14 kinds of urinary nucleosides from 52 patients with colorectal cancer, 10 patients with intestinal villous adenoma and 60 healthy adults were determined by column switching high performance liquid chromatography method. RESULTS: The mean levels of 12 kinds of urinary nucleosides (except uridine and guanosine) in the patients with colorectal cancer were significantly higher than those in patients with intestinal villous adenoma or the healthy adults. Using the levels of 14 kinds of urinary nucleosides as the data vectors for principal component analysis, 71% (37/52) patients with colorectal cancer were correctly classified from healthy adults, in which the identification rate was much higher than that of CEA method (29%). Only 10% (1/10) of patients with intestinal villous adenoma were indistinguishable from patients with colorectal cancer. The levels of m1G, Pseu and m1A were positively related with tumor size and Duke's stages of colorectal cancer. When monitoring the changes in urinary nucleoside concentrations of patients with colorectal cancer associated with surgery, it was found that the overall correlations with clinical assessment were 84% (27/32) and 91% (10/11) in response group and progressive group, respectively. CONCLUSION: These findings indicate that urinary nucleosides determined by column switching high performance liquid chromatography method may be useful as biological markers for colorectal cancer.