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Biologists often use systems of ontologies to classify gene lists obtained by high-throughput gene or protein-sequencing instruments, and then enrichment scores were used to rank the ontology system. Therefore, the important molecular functional categories related to the phenotype can be conveniently viewed in the ontology system. Since the birth of GO (Gene Ontology) organization, various types of ontology software have been developed to calculate enrichment scores for the target gene list in the GO system. Herein, we provide an enrichment calculation application oppOntology (Omics Pilot Platform for Ontology) developed by MATLAB. oppOntology supports simultaneous calculation of multiple samples with manifold enrichment scores (GeneCount, GeneRatio, EnrichFactor, HypergeometricTest, and FisherExactTest). oppOntology can not only calculate enrichment scores for generic functional databases, such as GO, KEGG, HPO, and MsigDB, but also for self-defined functional category databases and customized GO Slim. Moreover, oppOntology supports online mapping of KEGG pathway diagrams in a batch way. The GUI (Graphical User Interface) of oppOntology is developed on the architecture of AppDesigner in MATLAB, and all input and output files are Microsoft Excel. oppOntology is an independent, easy-to-use enrichment calculation software, that can be available at https://github.com/HangZhouSheep/oppOntology ., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

The discovery of new lncRNAs (long noncoding RNAs) and their regulatory pathways has always been a hotspot in the field of ceRNA (competing endogenous RNA). Herein, we report opplncRNA (Omics Pilot Platform of lncRNA), a novel and rapid tool for investigating lncRNA-miRNA-mRNA interactions based on the architecture of MATLAB AppDesigner. opplncRNA is useful to analyze the regulatory interaction networks of lncRNA with a friendly GUI (graphical user interface). There are three lncRNA databases (ENCORI, LncBase, and miRcode) about lncRNA-miRNA interactions that have been integrated into opplncRNA, as well as seven miRNA databases (miRcode, ENCORI, TarBase, miRTarBase, miRDB, miRanda, and miRecords) about miRNA-mRNA interactions as also. opplncRNA can read expression data from any profile techniques, such as microarray or RNA-seq. Then, the relationships between lncRNA-miRNA and miRNA-mRNA can be directly calculated through the profile data of lncRNA, miRNA, and mRNA by the threshold of correlation coefficients. Integrated databases can be used to filter calculation outcomes to obtain more reliable pathways. Moreover, opplncRNA has the functionality of directly demonstrating 3 layers network from lncRNA to mRNA in command line form., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

The mechanisms by which prostate cancer (PCa) progresses to the aggressive castration-resistant stage remain uncertain. Zinc finger of the cerebellum 5 (ZIC5), a transcription factor belonging to the ZIC family, is involved in the pathology of various cancers. However, the potential effect of ZIC5 on PCa malignant progression has not been fully defined. Here, we show that ZIC5 is upregulated in PCa, particularly in metastatic lesions, in positive association with poor prognosis. Genetic inhibition of ZIC5 in PCa cells obviously attenuated invasion and metastasis and blunted the oncogenic properties of colony formation. Mechanistically, ZIC5 functioned as a transcription factor to promote TWIST1-mediated EMT progression or as a cofactor to strengthen the β-catenin-TCF4 association and stimulate Wnt/β-catenin signaling. Importantly, ZIC5 and the androgen receptor (AR) form a positive feed-forward loop to mutually stimulate each other's expression. AR, in cooperation with its steroid receptor coactivator 3 (SRC-3), increased ZIC5 expression through binding to the miR-27b-3p promoter and repressing miR-27b-3p transcription. In turn, ZIC5 potentiated AR, AR-V7, and AR targets' expression. Besides, ZIC5 inhibition reduced AR and AR-V7 protein expression and enhanced the sensitivity of PCa to enzalutamide (Enz) treatment, both in vitro and in vivo. These findings indicate that the reciprocal activation between AR and ZIC5 promotes metastasis and Enz resistance of PCa and suggest the therapeutic value of cotargeting ZIC5 and AR for the treatment of advanced PCa., (© 2022. The Author(s).)

Exploring the biological function of periostin (POSTN) in prostate cancer (PCa) bone metastasis is of importance. It was observed that the expression of POSTN was high in PCa, especially highest in PCa metastasized to bone. In this study, we found that inhibiting POSTN in PCa cells could significantly alleviate PCa bone metastasis in vivo , suggesting POSTN is a promising therapeutic target. Since, due to the secreted expression of POSTN in osteoblasts and PCa, we hypothesized the positive feedback loop between osteoblasts and PCa mediated by POSTN in PCa bone metastasis. The in vitro experiments demonstrated that osteoblast-derived POSTN promoted PCa cell proliferation and invasion and PCa cell-derived POSTN promotes proliferation of osteoblasts. Furthermore, we found that POSTN regulated PCa and osteoblast function through integrin receptors. Finally, 18 F-Alfatide II was used as the molecule probe of integrin αvβ3 in PET-CT, revealing high intake in metastatic lesions. Our findings together indicate that targeting POSTN in PCa cells as well as in the osteoblastic may be an effective treatment for PCa bone metastasis., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Sun, Mi, Ge, Hu, Xu, Guo, Tan, Zhang, Zhong and Xia.)

Background and Objectives: Vancomycin is one of the most commonly used antibiotics for intra-articular (IA) infusion in the treatment of prosthetic joint infection (PJI). This study aimed to preliminarily investigate the serum and synovial vancomycin concentrations in patients with PJI after IA infusion., Methods: In total, 16 patients who developed PJI were enrolled in this study; 14 of the patients were treated with IA infusion of vancomycin postoperatively, while the other 2 patients received intravenous (IV) infusion of vancomycin alone. Chemiluminescent immunoassay assay (CLIA) and high-performance liquid chromatography (HPLC) were used to determine the serum and synovial vancomycin concentrations, respectively., Results: Administration of vancomycin 0.5 g once daily (qd) IA maintained a high vancomycin trough concentration in synovial fluid before the next IA dose, regardless of whether it was given in combination with IV administration. The combination vancomycin 0.5 g qd IA + vancomycin 1 g every 12 h (q12h) IV yielded relatively good trough concentrations of vancomycin in both serum and synovial fluid. The mean trough serum vancomycin concentration of patients who used vancomycin 1 g q12h IV therapy was above 10 μg/mL; however, no vancomycin was detected in their synovial fluid., Conclusions: The rational use of IA vancomycin infusion may help to achieve effective therapeutic concentrations of vancomycin in the serum and synovial fluid of patients with PJI., (© 2021. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

A composite Mn-Cu-Ce tri-metal oxide supported on γ-Al 2 O 3 (Mn-Cu-Ce/Al 2 O 3 ) catalyst was prepared by an impregnation-calcination method and investigated in the catalytic ozonation treatment of real coal chemical wastewater (CCW). The catalyst was characterized by XRD, SEM, TEM, XRF, BET, and XPS techniques. The results showed that Mn, Cu, and Ce metal oxides were evenly distributed on the Al 2 O 3 surface and the catalyst maintained a large surface area and a high pore volume compared with the pristine Al 2 O 3 . The synergy between Mn, Cu, and Ce oxides greatly enriched the catalytic active sites and enhanced the ozonation performance. The catalytic ozonation process with Mn-Cu-Ce/Al 2 O 3 increased the removal rate of total organic carbon (TOC) by 31.6% compared with ozonation alone. The ketones, aromatic compounds, phenols, and nitrogen-containing heterocyclic compounds in CCW have been effectively degraded and mineralized by Mn-Cu-Ce/Al 2 O 3 catalytic ozonation process, and its biodegradability has also been significantly improved. The experimental results of ∙OH scavengers revealed that the mechanism of Mn-Cu-Ce/Al 2 O 3 catalytic ozonation was to promote the generation of ∙OH radicals. The catalytic activity of Mn-Cu-Ce/Al 2 O 3 was only a slight decrease in six consecutive catalytic ozonation treatments, showing good stability. Therefore, Mn-Cu-Ce/Al 2 O 3 can be used as a candidate catalyst for the advanced treatment of refractory organic wastewaters upon catalytic ozonation., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Ginsenoside Rd (GS-Rd), isolated from the Chinese traditional herbal medicine Panax ginseng , is used for the treatment of cardiovascular diseases, inflammation, different body pains, and trauma. Caspase-3 and Caspase-9 belong to cysteine aspartic acid specific protease (Caspase) family that plays an important role in apoptosis progression of cancers. In the present study, we investigated the anti-tumor effect of GS-Rd by MTT assay, colony formation assessment, flow cytometry, and Western blotting. Our results revealed that ginsenoside Rd significantly inhibits human gastric cancer (GC) growth and cell proliferation. Flow cytometer analysis showed that the GS-Rd could significantly induce apoptosis and arrest the G0/G1 phase in GC cells. Further, GS-Rd was found to increase the ratio of Bax/Bcl-2 and the expression of Caspase-3 and Caspase-9, respectively, and to decrease the expression of Cyclin D1. Taken together, our study suggests that GS-Rd significantly inhibits GC cell proliferation, induces cell apoptosis through increase the expression of Caspase-3, Caspase-9, and the ratio of Bax/Bcl-2. GS-Rd also induces cell cycle arrest at G0/G1 phase by down-regulation Cyclin D1. Thus, GS-Rd could serve as a lead to develop novel therapeutic agents to against human gastric cancer.

Multidrug resistance is one of the reasons for low survival of advanced hepatocellular carcinoma (HCC). Our previous studies indicate that the hedgehog signalling is involved in hepatic carcinogenesis, metastasis and chemo-resistance. The present study aims to uncover molecular mechanisms underlying hepatoma chemo-resistance. TAP1 and GLI1/2 gene expression was assessed in both poorly differentiated hepatoma cells and HCC specimens. Potential GLI-binding site in the TAP1 promoter sequence was validated by molecular assays. Approximately 75% HCC specimens exhibited an elevated expression of hedgehog GLI1 transcription factor compared with adjacent liver tissue. Both GLI1/2 and TAP1 protein levels were significantly elevated in poorly differentiated hepatoma cells. Both Huh-7-trans and Huh-7-DN displayed more karyotypic abnormalities and differential gene expression profiles than their native Huh-7 cells. Sensitivity to Sorafenib, doxorubicin and cisplatin was remarkably improved after either GLI1 or TAP1 gene was inhibited by an RNAi approach or by a specific GLI1/2 inhibitor, GANT61. Further experiments confirmed that hedgehog transcription factor GLI1/2 binds to the TAP1 promoter, indicating that TAP1 is one of GLI1/2 target genes. In conclusion, TAP1 is under direct transcriptional control of the hedgehog signalling. Targeting hedgehog signalling confers a novel insight into alleviating drug resistance in the treatment of refractory HCC., (© 2020 The Authors. Journal of Cellular and Molecular Medicine published by by Foundation for Cellular and Molecular Medicine and John Wiley & Sons Ltd.)

Ectopic parathyroid adenomas that affect the submandibular region have not been widely reported. We describe a 34-year-old man who presented with a painless swelling of the submandibular region. The identification of hypercalcaemia encouraged us to engage a multidisciplinary team to evaluate further serum changes. Parathyroid hormone analysis, 99m Tc-methoxy-isobutyl-isonitrile ( 99m Tc-MIBI) scintigraphy, and single-photon emission computed tomography (SPECT-CT) were done to rule out hyperparathyroidism. Raised parathyroid hormone together with 99m Tc-MIBI and SPECT-CT examination were consistent with a tumour caused by the hyperparathyroidism. Removal of the lesion resulted in rapid improvement in serum calcium and parathyroid hormone, and the normalisation of the serum creatinine, concentrations. Histopathological analysis confirmed a parathyroid adenoma. We conclude that ectopic parathyroid adenomas should be considered as part of a differential diagnosis for tumours of the submandibular region., (Copyright © 2019 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.)

In this study, the methods of fluorescence spectroscopy and fluorescence quenching titration technique were used to identify the interactions between humic acid (HA) and roxarsone (ROX). Effects of HA concentration, pH and temperature on the bonding strength between HA and ROX were investigated. The results showed that the four fluorescence peaks (E(x)/E(m) = 300 nm/480 nm, 370 nm/480 nm, 420 nm/500 nm, 460 nm/520 nm, marked as peak A, B, C, D respectively) of HA could be quenched by ROX. The extent of decreases in fluorescence intensities of different peaks was different and followed the order of C > B > A > D. The common logarithm of association constants (lg K) between peak A and ROX increased slightly with the increase of HA concentration and were much larger than the bimolecular quenching constant of O2. It was confirmed that the carboxyl groups and the carboxide groups of HA were quenched statically by ROX. The lg K values fluctuated between 3.55 L x mol(-1) and 3.98 L x mol(-1) when pH ranged from 5.00 to 9.00, and the maximum value occurred at pH 6.00. It might be resulted from the fact that pH could change the formation of ROX and conformation of phenolic hydroxyl groups and carboxyl groups in HA. The lg K values decreased and fluctuated between 2.65 L x mol(-1) and 3.89 L x mol(-1) with temperature ranging from 25.0 degrees C to 55.0 degrees C, which further confirmed the static quenching interaction between HA and ROX. Transient-fluorescence spectrum analyses and liner model simulations revealed that single static quenching was the main mechanism between ROX and the functional groups of fluorescence peak A, B, D in HA, and combined dynamic and static quenching was the main mechanism between ROX and the functional groups of peak C in HA.

A gelatinolytic matrix metalloproteinase (gMMP) from grass carp skeletal muscle was purified by 30-70% ammonium sulphate fractionation and a combination of chromatographic steps including ion exchange on DEAE-Sephacel, gel filtration on Sephacryl S-200, and affinity on gelatin-sepharose. The molecular weight of the proteinase as estimated by SDS-PAGE was 70 kDa under non-reducing conditions. The enzyme revealed high activity from 30 to 50 °C, and the gelatin hydrolysing activity was investigated at a slightly alkaline pH range using gelatin as substrate. Metalloproteinase inhibitor EDTA completely suppressed the gelatinolytic activity, while other proteinase inhibitors did not show any inhibitory effect. Divalent metal ion Ca(2+) was essential for the gelatinolytic activity. Further, peptide mass fingerprinting obtained four fragments with 45 amino acid residues, which were highly identical to MMP-2 from fish species. The gMMP could effectively hydrolyse type I collagen even at 4 °C, suggesting its involvement in the texture softening of fish muscle during the post-mortem stage., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Purpose: To study oral precancerous lesion and oral cancer by using micro PET/CT., Methods: Thirty-nine SD rats were divided into experimental group and control group. 33 of them were raised with a 4-nitroquinoline-1-oxide (4NQO) solution with the concentration of 0.002% during the first 13 weeks, and then changed to normal water. The other 6 rats drank normal water all the time. During 25th to 30th week of the experiment, 2-Deoxy-2-[F-18]fluoro-D-glucose (FDG)-PET/CT was performed for these rats. One day after imaging, pathological examination was performed. SUVmax and T/NT were investigated according to pathological results. SAS6.0 software package was used for statistical analysis., Results: There was no significant difference in SUVmax among the normal group, precancerous group and cancerous group (P>0.05). There was significant difference in T/NT(muscle, brain) between the normal group and the cancerous group (P<0.05). But there was no significant difference between the normal group and the precancerous group (P>0.05); and no significant difference between the precancerous group and the cancerous group (P>0.05). The T/NT (muscle, brain) ratios increased along with the increase of the pathologic grade of the lesions. There was no significant difference in T/NT(thyroid) among the three groups and no correlation between the T/NT(thyroid) ratios and the pathologic grade., Conclusions: Micro PET/CT, as a non-invasive technology, may contribute to the dynamic studies of the process of carcinogenesis. T/NT(muscle, brain) ratios could show the degree of lesions of rat's tongue during carcinogenesis.

The α-tocopherol transfer protein (α-TTP) is a ~32 kDa protein that exhibits a marked ligand specificity and selectively recognizes of α-tocopherol, which is the most active form of vitamin E. The α-TTP gene has been cloned and its physiological functions have been studied in numbers of species, however, the understanding of sheep α-TTP is still in his infancy. In this study, the full-length cDNA of sheep α-TTP gene was cloned from sheep liver by using of rapid amplification of complementary DNA ends (RACE). As a result, the sheep α-TTP gene was 1098 bp in nucleotide which contained 23 bp 5'-untranslated region (UTR), 226 bp 3'-UTR and 849 bp open reading frame (ORF) that encoded a basic protein of 282 amino acids. Further bioinformatic analysis indicated that the sheep α-TTP gene had a high homologous of both nucleotide and amino acid sequences compared with that of other species and had a Sec14p-like lipid-binding domain which called the CRAL-TRIO domain. Moreover, the expression of sheep α-TTP mRNA and protein in response to different vitamin E supplemented levels were observed according to quantitative real-time PCR (qRT-PCR) and Western blotting analysis. The results showed that dietary vitamin E levels did not affect α-TTP mRNA expression significantly while the low vitamin E supplemented level groups of sheep had significantly higher α-TTP protein compared to high-vitamin E groups., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Spray drying is an important processing of producing modificatied yolk powder (MEYP). To investigate the correlation between the secondary structure and emulsifying property of MEYP made at different spray-drying-temperatures, Fourier transform infrared spectroscopy (FTIR) was applied in the present study. The result indicated that emulsifiability and the percentage of alpha-helix were both significantly increased firstly and then remarkably decreased with rising of spray-drying-temperature, and the emulsifying property of MEYP was relative to the percentage of alpha-helix. After heat-treating, the percentage of alpha-helix was significantly decreased and the percentage of p-sheet was remarkably increased, however, the total percentage of the two structures was maintained. The stable total percentage of alpha-helix and beta-sheet would be a good explanation for the great heat stability of emulsion presented in the MEYP made at different spray-drying temperature.

Interaction of lactoferrin and its peptides LfcinB4-14 and LfampinB with dipalmitoylglycero-phosphocholine (DPPC) and dipalmitoylglycero-phosphoglycerol (DPPG) liposomes were studied by means of Raman spectroscopy. In our study, conformational changes in the phospholipid molecules were investigated by measuring the intensities of 2 847 and 2 882 cm(-1) Raman bands which are assigned to acyl chains' symmetric and asymmetric C-H stretching vibrations. The addition of lactoferrin and its peptides LfcinB4-14 and LfampinB caused a decrease in the 2 882 cm(-1) intensity of DPPG liposomes, thus the order parameter for the lateral interactions between chains S(lat) decreased from 0.19 to 0.17, 0.14 and 0.12 respectively. On the contrary, the intensities at 2 847 and 2 882 cm(-1) of DPPC liposomes were poorly affected by lactoferrin and its peptides. The results show that lactoferrin and its peptides present a stronger effect on the molecular structure and order degree of anionic lipid DPPG than that of zwitterionic lipid DPPC. This suggests that lactoferrin, LfcinB4-14 and LfampinB can interact and combine with the negatively charged DPPG liposomes by electrostatic interaction and perform its antibacterial activity. Besides, LfcinB4-14 and LfampinB can affect the lipid more strongly than lactoferrin.

The immunoactivity was evaluated of Dendrobium officinale Kimura & Migo, a Chinese herbal plant, and its crude polysaccharides. Different dosages of D. officinale and its polysaccharides were orally administered to healthy BALB/c mice. The control group was given distilled water. After 4 weeks, immune parameters, including cellular immunity (delayed-type hypersensitivity and natural killer cell activity), humoral immunity (serum hemolytic complement activity), nonspecific immunity (peritoneal macrophage phagocytosis) and interferon-gamma production by splenocytes were measured. The results showed that D. officinale and its polysaccharides can significantly enhance cellular immunity and nonspecific immunity in mice. Humoral immunity was also enhanced after oral administration of D. officinale, but the polysaccharides had no influence. Both D. officinale and its polysaccharides markedly increased IFN-gamma production by murine splenocytes. Six fractions were isolated from the polysaccharides; the molecular weight of the major fraction was 533,700 Da, and composed of mannose, glucose and rhamnose in a molar ratio of 7.3:1.3:1.0.

A strain of bacterium capable of biodegrading microcystin (MC) RR and MC-LR was isolated from the sediments of Dianchi Lake. It was demonstrated that the enzymes in cell-free extract of this bacterium were responsible for the degradation of MC-RR and MC-LR, and the dead-end products of MC-RR and MC-LR catalyzed by these enzymes were observed on HPLC chromatograms. Results show that the optimum pH for the activities of these enzymes was in the range from 6.0 to 8.0, however the metal ions of Cu2+, Mn2+ and Zn2+ had no apparent effects on the enzymatic degradation of MC-RR and MC-LR.

Purpose: To investigate the effects of stress on periodontitis., Methods: 44 chronic periodontitis patients and 42 patients with healthy periodontal tissues(as control) were enrolled in the study. All subjects were required to complete a questionnaire which was mainly made up of the symptom checklist 90. Data collected included clinic parameters, psychological factors, life events and basic socio-demographics. The results were statistically assessed by SPSS 10.0 software., Results: There was significant difference between periodontitis group and the control group in education, marital status, and life events (P<0.05 or P<0.01). Compared with the controls, the periodontitis patients got higher scores in somatization, obsessive-compulsive, interpersonal sensitivity, depression, anxiety, hostility, the impact of sleep and diet (P<0.05 or P<0.01). In periodontitis group, there was significant correlation between CPITN, CI and depression, anxiety, interpersonal sensitivity, etc. (P<0.01 or P<0.05)., Conclusions: In this sample, there was a close association between stress and periodontitis. Stress may be a significant risk indicator for periodontitis.

Objective: To detect the differentially expressed genes in human polycystic kidney by cDNA microarray., Methods: The PCR products of 8398 genes were spotted onto a chip in array. Both mRNAs isolated from polycystic kidney tissue and normal kidney tissue were reversely transcribed to cDNAs with the incorporation of fluorescent dUTP (Cy5-dUTP and Cy3-dUTP) for preparing the hybridization probes. The mixed probes were hybridized to the cDNA microarray. Then the cDNA microarray was scanned for the fluorescent signals and the display of differences between the 2 tissues. IGF1 mRNA, one of the up regulated genes was detected by in situ hybridization technique in the two tissues to validate the result from cDNA microarray., Results: The result indicated that the expressions of 263 genes were up regulated while the expressions of 94 genes were down regulated in the polycystic kidney tissue among the 8398 target genes. Bioinformatical analysis of those genes had been performed. The up-regulated genes were mainly the ones of oncogene, cellular skeleton and movement, apoptosis related protein, cell signal transduction protein, and cytokine. The down regulated genes were mainly the ones of anti-oncogene, DNA binding and transcription factors, cell signal transduction protein, and metabolism protein. The IGF1 mRNA expression detected by in situ hybridization was consequently consistent with the cDNA microarray., Conclusion: cDNA microarray is an effective and quick method for studying differential expressed genes. Three hundred and fifty-seven differentially expressed genes with different functions were revealed in the polycystic kidney tissue, which may play some roles in the progression of polycystic kidney.

The process of decay of photo-generated electrons in the conduction band of ZnO:Zn and ZnO powder materials after excitation with a ultra-short pulse laser has been investigated in this paper by microwave absorption method. The excitation and emission spectra of ZnO:Zn were measured at room temperature. It was measured that the lifetime o photoelectrons in the materials ZnOand ZnO:Zn are 64 ns and 336 ns respectively. It is believed that the increase of the lifetime in the material of ZnO:Zn is due to the prolong of relaxation time caused by the defect structure in the material.

Extracellular field excitatory postsynaptic potentials (fEPSPs) were recorded in area CA1 of rat hippocampal slices in vitro. The responses evoked by spontaneously released glutamate and GABA were recorded from area CA1 pyramidal neurons in rat hippocampal slices in whole-cell mode. The glutamate and GABA receptor-associated ligand-gated currents were obtained from dissociated single hippocampal pyramidal cells. The results showed that 4-aminopyridine (4-AP) had obvious effects on both presynaptic and postsynaptic events. Applications of 4-AP in micromolar concentration resulted in persistent enhancement of the initial slope of fEPSPs with the half-maximal enhancement concentration (EC(50)) of 46.7+/-2.68 microM. At the concentration of 200 microM, 4-AP increased the initial slopes of the total fEPSPs, NMDA- and AMPA-mediated fEPSPs components to 225.6+/-23.8%, 177.4+/-20.1% and 142.3+/-18.9%, respectively, but had no effect on the fiber volley. The half-maximal stimulus intensity to induce responses was reduced from 5.14+/-0.27 to 3.58+/-0.23 V. The frequencies of mEPSCs and mIPSCs were increased to 324.2+/-25.4% and 287.3+/-36.3% by 200 microM 4-AP. The amplitude histograms of mEPSCs and mIPSCs were fitted with Gaussian distributions. After 200 microM 4-AP application, the first and second peaks in Gaussian distributions of mEPSCs were shifted from 8.73+/-0.94 and 17.78+/-2.13pA to 10.48+/-0.82 and 21.14+/-2.45 pA, while those of mIPSCs were shifted from 13.65+/-0.96 and 25.51+/-2.95 pA to 11.21+/-1.04 and 23.08+/-2.37 pA. At 200 microM, 4-AP reduced paired-pulse facilitation and accelerated synaptic fatigue induced by stimulation at 10 Hz (for 1 s) and the ratio of fEPSPs(10)/fEPSPs(1) was decreased from 1.62+/-0.16 to 0.61+/-0.15. At 200 microM, 4-AP inhibited postsynaptic GABA currents induced by 5 microM GABA to 68.2+/-15.5%: by countering the effect of enhanced release of GABA from presynaptic terminals, this could depress the inhibitory pathway. Also at 200 microM, 4-AP increased NMDA currents to 155.3+/-17.8%, but had no significant effect on AMPA currents (94.2+/-15.6%). Our experimental results thus show that 4-AP-induced changes of synaptic transmission in area CA1 of rat hippocampus may be attributed to 4-AP's effects on both presynaptic terminals and postsynaptic receptors.

Modulation of the voltage-dependent transient outward potassium current (IA) by Pb2+ was studied in acutely dissociated rat hippocampal pyramidal cells from the CA1 region at postnatal ages 7-14 days using the conventional whole-cell patch-clamp technique. In the presence of different concentrations of external Pb2+, the initial delay and activation time of IA were concentration-dependently lengthened. In particular, the initial delay was even longer in 1 mM Pb2+, showing no signs of saturation. Pb2+ also slowed the inactivation of IA, for decay time constants in the presence of Pb2+ were increased under the same experimental protocols. The activation curves, which were reasonably fitted by a single Boltzmann function, illustrated that Pb2+ increased the voltage threshold of IA and shifted the normalized activation current-voltage curves to more depolarizing voltage commands. Moreover, Pb2+ significantly affected the steady-state inactivation of IA. The application of Pb 2+ made the curves of the steady-state inactivation of IA shift to more depolarizing voltages with little change in the slopes factors. In brief, the results demonstrated that Pb2+ is a dose- and voltage-dependent, reversible blocker of IA currents of hippocampal CA1 neurons. The observations were fitted by the revised "Kuo and Chen type model", which postulates a Pb2+-selective site near the pore of the IA channel and that modulation of the IA channel by Pb2+ is the result of the competitive influences of Pb2+ on opening and inactivating different pathways.

Objective: To investigate the effect of stress on Guinea Pigs' periodontitis model., Methods: 24 periodontitis models of guinea pigs were provided by inoculating Actinobacillus actinomycetemcomitans (Aa) and Porphyromonas gingivalis (Pg) in the gingival sulcus. The guinea pigs were divided into two groups: stress group(stimulated with cold bath and fright) and control group(without stimulations). Three animals of each group were sacrificed successively at 1, 2, 4, 6 week after inoculation. Clinical and histological evaluation, cortisol concentration examinations, osteoclast and osteoblast numbers account were applied., Results: The cortisol concentration of stress group was significantly higher than that of control group at 1, 2, 4 week after stressed(P < 0.05 or P < 0.01). Pocket depth in stress group was significantly deeper than that in control group at 2, 4 week (P < 0.05), Compared with control group, the stress group demonstrated more active tissue damage and alveolar bone resorption. The bone repair in stress group was not as active as in control group. The osteoclast numbers in stress group was significantly higher than that in control group at 1, 4, 6 week (P < 0.05)., Conclusions: Stress could enhance the destruction of periodontal tissues infected by pathogenic bacteria and increase disease susceptibility. It was concluded that stress was a significant risk indicator for periodontitis.

The effects of ferrous ions (Fe(2+)) on taurine-induced Cl(-) current (I(tau)) recorded from single neurons, which was freshly isolated from the rat hippocampal CA1 area, were studied with conventional whole-cell recording under voltage-clamp conditions. Using standard pharmacological approaches, we found that the currents gated by concentrations of taurine (

Objective: In order to search the cause of dental caries and periodontitis., Methods: Selected 70 patients with severe chronic periodontitis (CP group) and 50 patients with caries sensitivity (CS group) in clinical adults of oral medicine (18 to 50-year-old) during 1 year. Parameters of oral hygiene, caries and periodontitis were recorded in the typical groups of CP and CS., Results: The patients of CP group had rare caries, DFS in the groups of CP and CS was 1.46+/-2.60 and 17.32+/-7.55 respectively(p<0.001),while the patients of CS group had relative periodontal health indeed, CPTNI in CS and CP groups were 0.98+/-0.63 and 3.24+/-0.62 respectively (p<0.001), and the number of missing teeth was 1.90+/-3.34 and 1.10+/-1.85 respectively(p>0.05). 3 patients(only 2.4%)confirmed the parameters of caries sensitive as well as severe periodontitis., Conclusion: The correlating pathogenesis of caries and periodontitis seems to have antiagonism tendency. The ecological connection and bacterial interaction are worthy of further study.

The conventional whole cell patch-clamp technique was used to measure the resting membrane conductance and membrane currents of nonstimulated cultured human umbilical vein endothelial cells (HUVECs) in different ionic conditions. Three electrophysiological phenotypes of cultured HUVECs (n = 122) were determined: first, 20% of cells as type I mainly displaying the inwardly rectifying potassium current (IKi); second, 38% of cells as type II in which IKi was super-posed on a TEA-sensitive, delayed rectifying current; third, 27% of cells as type III predominantly displaying the outwardly rectifying current which was sensitive to TEA and slightly inhibited by a chloride channel blocker niflumic acid (N.A.). In cells of type I, the mean zero-current potential (V0) was dependent on extracellular K+ ([K+]o) but not on Cl-, indicating major permeability to K+. Whereas V0 of type II was also affected by extracellular Cl- ([Cl-]o), indicating the contribution of an outward Cl- current in setting V0. The cells of type III were not sensitive to decrease of [Cl-]o and the outward current was activated in a relative stable voltage range. This varying phenotypic expression and multipotential behavior of HUVECs suggests that the electrical features of HUVEC may be primarily determined by embryonic origin and local effect of the microenvironment. This research provided the detailed electrophysiological knowledge of the endothelial cells.

The effects of Fe(2+) on the properties of three types of ion channels were studied in acutely dissociated rat hippocampal pyramidal neurons from area CA1 at postnatal ages of 7-14 days using the whole cell patch clamp technique. The results indicated that: (1) in the existence of Fe(2+), the activation voltage threshold of transient outward K(+) currents (I(A)) was decreased. The normalized current-voltage curves of activation were well fitted with a single Boltzmann function, and the V(1/2) was 2.44+/-1.14 mV (n=15) in control, whereas 1.79+/-1.53 (n=15), -2.96+/-0.92 (n=14), -5.11+/-1.31 (n=13), -9.05+/-1.64 mV (n=12) in 1, 10, 100 and 1000 microM Fe(2+), respectively. Differences between two groups were significant (P<0.05, n=12-15), except for that between the control and 1 microM (P>0.05, n=15). (2) Fe(2+) caused a left shift of the current-voltage curves of steady-state inactivation of I(A) in a concentration-dependent manner. The curves were well fitted with a single Boltzmann function with similar slope (P>0.05, n=10-13). The V(1/2) were -70.71+/-1.23 (n=13), -71.14+/-1.37 (n=13), -78.21+/-1.17 (n=11), -84.61+/-1.34 (n=12), and -89.68+/-2.59 mV (n=10) in control, 1, 10, 100 and 1000 microM Fe(2+), respectively. Fe(2+) also shifted the current-voltage curves of Na(+) channel steady-state inactivation to more negative depolarization potentials in parallel, with V(1/2), -67.37+/-1.33 mV (n=12) in control, and -67.52+/-1.28 mV (n=12), -68.24+/-1.61 mV (n=10), -71.58+/-1.45 mV (n=10), -76.65+/-1.76 mV (n=9) in 1, 10, 100 and 1000 microM Fe(2+) solutions, respectively. (3) In Fe(2+) solutions, the recovery from inactivation of I(A) was slowed. (4) With application of different concentrations of Fe(2+), the voltage threshold of activation of delayed rectified outward K(+) currents (I(K)) was decreased, while Fe(2+) showed a little inhibition at more positive depolarization. Briefly, the results demonstrated that Fe(2+) is a dose- and voltage-dependent, reversible modulator of I(A), I(K) and Na(+) channels. The results will be helpful to explain the mechanism of Fe(2+) physiological function and Fe(2+) intoxication in the central nervous system.

Previous studies have demonstrated that low-level lead exposure can impair the induction of long-term depression (LTD) in area CA1 and dentate gyrus (DG) of rat hippocampus in vitro and in vivo. The induction of LTD in area CA1 and DG has been shown to associate with N-methyl-D-aspartate receptors (NMDARs) and voltage-gated calcium channel (VGCC). In this study, the relative contributions of NMDARs-dependent and VGCC-dependent components in the induction of LTD in the hippocampus and the impairments of these two components of LTD by chronic low-level lead exposure were investigated. Neonatal Wistar rats were exposed to lead from parturition to weaning via milk of dams drinking 0.2% lead acetate solution. Field excitatory postsynaptic potentials (EPSPs) were recorded in area CA1 and DG before and after two 15-min trains of 1-Hz low-frequency stimulation (LFS) (2x900 pulses). In area CA1, the amplitude of NMDARs-dependent LTD (NMDA-LTD), in the presence of 10 microM nimodipine (a blocker of L-type Ca(2+) channels), was 80.05+/-2.54% (n=8) and 94.58+/-10.57% (n=8) in the control and lead-exposed rats, respectively. The amplitude of VGCC-dependent LTD (VGCC-LTD), in the presence of 50 microM (-)-2-amino-5-phosphonopentanoic acid (AP5), was 80.36+/-4.08% (n=10) and 93.91+/-7.85% (n=10) in the control and lead-exposed rats, respectively. In area DG the amplitude of NMDA-LTD, with both 50 microM Ni(2+) (a blocker of T-type Ca(2+) channels) and 10 microM nimodipine present, in the control rats (79. 97+/-4.30%, n=8) was significantly larger than that in the lead-exposed rats (91.24+/-11.08%, n=10, P<0.001). The amplitude of VGCC-LTD, with 50 microM AP5 present, was significantly larger in the control rats (70.80+/-3.64%, n=9) than that in the lead-exposed rats (87.60+/-9.00%, n=10, P<0.001). The results suggested that chronic lead exposure affected two components of LTD induction in area CA1 and DG. Furthermore, the impairment of two components by lead exposure might be similar in area CA1, while the impairment of VGCC-LTD might be more serious in DG of hippocampus.

Chronic developmental lead (Pb) exposure to the rat has been reported to impair the long-term potentiation (LTP) in area CA1 and DG of the hippocampus. The present study was performed to investigate the effects of chronic Pb exposure on homosynaptic short-term depression (STD) and long-term depression (LTD) of population spikes (PS) in area CA1 of the rat hippocampus in vivo. Neonatal Wistar rats were exposed to Pb from parturition to weaning via the milk of dams fed with 0.2% lead acetate solution. The input/output (I/O) function, paired-pulse reaction (PPR), the PS were measured in the area CA1 in response to low frequency stimulation (LFS). The results showed that the homo-STD amplitude of PS depotentiation in Pb-exposed rats (87.48 +/- 7.44%, n = 14) was less significant than that in control rats (72.34 +/- 6.05%, n = 18, P<0.05), and the homo-LTD amplitude of PS depotentiation in Pb-exposed rats (72.80 +/- 5.86%, n = 14) was even less significant than that in control rats (47.80 +/- 5.03%, n = 18, P<0.01). The results suggest that chronic Pb exposure in neonatal rats caused impairments in the STD and LTD of area CA1 of hippocampus.

Chronic developmental lead exposure is known to be associated with cognitive dysfunction in children. Impairment of the induction of long-term depression (LTD) has been reported in area CA1 and dentate gyrus (DG) of rat hippocampus following chronic lead exposure. The present study was carried out to investigate age-related alterations of LTD in area CA1 and DG of rat hippocampus following developmental lead exposure in vitro. Neonatal Wistar rats were exposed to lead from parturition to weaning via milk of dams drinking 0.2% lead acetate solution. Field excitatory postsynaptic potentials (EPSPs) were recorded in hippocampal slices at various postnatal ages: postnatal day (PND) 17-23, 27-33, and 57-63. Following low-frequency stimulation (LFS, 900 pulses/1 Hz), the average magnitude of LTD is age related. In the controls, LTD magnitude in area CA1 decreased with age, whereas in DG it increased with age. In the lead-exposed groups, the magnitude of LTD declined during development in both area CA1 and DG. The differences of LTD magnitude between the control and lead-exposed rats were 27.26 +/- 9.15% (PND 17-23), 21.59 +/- 12.93% (PND 27-33), and 16.96 +/- 9.33% (PND 57-63) in area CA1, and were 6.95 +/- 9.26%, 17.60 +/- 3.91%, and 33.63 +/- 10.47% in DG, respectively. These results demonstrated that the lead-induced impairment of LTD magnitude was an age-related decline in area CA1 and an age-related increase in area DG of rat hippocampus. Published by Elsevier Science Inc.

Long-term potentiation (LTP) and long-term depression (LTD), two forms of synaptic plasticity, are believed to underlie the mechanisms of learning and memory. Previous studies have demonstrated that low-level lead exposure can impair the induction and maintenance of LTP in vivo and in vitro. The present study was carried out to investigate whether the low-level lead exposure affected the induction and maintenance of LTD. Neonatal Wistar rats were exposed to lead from parturition to weaning via milk of dams drinking 0.2% lead acetate solution. Field excitatory postsynaptic potentials (EPSPs) were recorded in hippocampal slices in adult rats (50-65 days) to study the alterations of LTD in area CA1 and dentate gyrus (DG) of hippocampus following chronic lead exposure. The input-output (I/O) curves before conditioning in both areas showed no evident alterations in basic synaptic transmission between the control and lead exposure groups. In area CA1, the mean amplitude of EPSP slope in control rats (61+/-11%, n=15) decreased significantly greater than that in lead-exposed rats (78+/-8%, n=8, P<0.05) following low frequency stimulation (LFS, 1 Hz, 15 min), which lasted at least 45 min. In area DG, with application of the same LFS, the LTD was induced in control rats (72+/-22%, n=8), while the LFS failed to induce LTD in lead-exposed rats (100+/-26%, n=8). These results showed that chronic lead exposure affected the induction of LTD in both area CA1 and DG. The effect of lead on synaptic plasticity in area CA1 was also investigated. The alteration of the amplitude of LTP in hippocampal slices caused by lead was reexamined in order to compare with that on LTD (control: 189+/-23, n=5; lead-exposed: 122+/-12, n=10). The result demonstrated that low-level lead exposure could reduce the range of synaptic plasticity, which might underlie the dysfunction of learning and memory caused by chronic lead exposure., (Copyright 1999 Elsevier Science B.V.)