Surface-independent CO2 and CO reduction on two-dimensional kagome metal KV3Sb5.

Two-dimensional kagome metals possess rich band structure characteristics, including Dirac points, flat bands, and van Hove singularities, because of their special geometric structures. Furthermore, kagome metals AV3Sb5 (A = K, Rb, and Cs) have garnered significant attention due to their nontrivial topological electronic structures. In this study, we theoretically demonstrate that the KV3Sb5 (001) surface is conducive to CO2 and CO reduction. The thermodynamic stability and electrochemical states of various surface types are investigated. The reaction paths reveal that the product is identical on different surfaces, and the free energy profiles exhibit low onset potentials. This paper elucidates the effect of two-dimensional topological kagome metals on CO2 and CO reduction.

Biphenylene network as sodium ion battery anode material.

Sodium ion batteries possess several advantages for large-scale energy storage, such as low cost and enhanced safety. However, graphite or other anode materials are not satisfactory because the large radius of Na+ hinders their embedding and removal in the charge and discharge processes. Recently, a biphenylene network (BPN), a two-dimensional (2D) carbon allotrope, has been synthesized. In this paper, we reveal the potential possibility of BPN as a Na storage material. The theoretical results indicate the advantages of BPN as a sodium battery anode. The maximum specific capacity (413 mA h g-1) is larger than that of the graphite-Li system (372 mA h g-1). With low Na+ diffusion barrier (<0.6 eV) and small volume expansion in the charging process (∼26%), BPN presents superiority to the graphite-Na system. Our findings show new insights into Na storage in BPN and provide guidance for the use of a BPN anode in sodium ion batteries.

Selective CO2 reduction on topological Chern magnet TbMn6Sn6.

As a new type of topological magnet, TbMn6Sn6 has a planar Mn kagome lattice with out-of-plane magnetic moments. Previous studies have found spin-polarized Chern gapped Dirac fermions in TbMn6Sn6, which are advantageous to topological catalysis. In this study, we theoretically demonstrate that the TbMn6Sn6 (001) surface is favorable for CO2 reduction. The stability of different surface types is investigated, and then the reaction paths of CO2 reduction on the surfaces are revealed to prove that the product is selective. This work reveals the effect of magnetic topological materials on CO2 reduction.

The correlation and role analysis of SLC30A1 and SLC30A10 in cervical carcinoma.

Background: SLC30 family genes, also known as ZnT family genes, can keep cellular zinc levels within a physiological range by exporting zinc to extracellular space or by isolating zinc in the specific regions of cytoplasm when cellular zinc concentrations are elevated in human cells. There are growing evidences that dysregulated expression of SLC30 family genes can potentially influence tumorigenesis. However, the expression and prognostic value of SLC30 family genes in cervical carcinoma are poorly characterized. Methods: In this study, we used many tools such as UALCAN, Kaplan-Meier Plotter, cBioPortal, LinkedOmics, FunRich, Metascape, GeneMANIA, Open targets and TISIDB to perform bioinformatics analysis of SLC30 family genes in cervical carcinoma. Results: We found that the expression of SLC30A1/7/10 was significantly higher in cervical carcinoma than that in normal matched tissues, while SLC30A2/8 mRNA levels were decreased compared to normal tissues. For tumor stages, SLC30A1, SLC30A7 and SLC30A10 groups significantly varied. And a high expression of SLC30A1, SLC30A6, SLC30A8 and SLC30A10 was associated with worse overall survival in cervical carcinoma patients. Besides, we found that SLC30A1/10 may have a potential regulatory role in immune infiltration in cervical carcinoma. In addition, the results showed that the high expression of SLC30A1 was resistant to 79 drugs or small molecules; Two drugs (Neopeltolide and Tozasertib) can inhibit the high expression of SLC30A10 in cancers. Conclusion: SLC30A1 and SLC30A10 can be recognized as potential diagnostic indicators and therapeutic targets in cervical carcinoma.

CO2 reduction on single-atom Ir catalysts with chemical functionalization.

As promising catalytic systems, single-atom catalysts (SACs) demonstrate improved catalytic performance for electrochemical reactions. However, the pinning of metal atoms on surfaces usually depends on the adsorption on defects. In this study, defect-free functionalization by attaching IrX3 (X = F or Cl) complexes on the MoS2 monolayer is theoretically demonstrated. The ligand-based method offers a damage-free route for stabilizing SACs on 2D materials. We demonstrate the CO2 reduction process on MoS2-IrX3 with a small change in free energy and a low onset potential. The d6 shell of Ir acts as a molecular joint with universal orbital orientations, which benefits the adsorption of different reaction intermediates. This study shows the superiority of defect-free functionalization of 2D materials using SAC-ligand complexes.

[Mechanical properties of 3D-printed titanium mesh and its biocompatibility in vitro].

PURPOSE: To compare the mechanical properties of 3D-printed titanium meshes and pre-shaped titanium meshes, and to evaluate the effects of 3D-printed titanium meshes on cell proliferation and differentiation. METHODS: 3D- printed titanium meshes were produced and prepared with laser printing machine. The mechanical properties were analyzed by static tension and compression load test. Bone marrow mesenchymal stem cells (BMSCs) were extracted from 4-week-old male SD rats. BMSCs were co-cultured with 3D-printed titanium meshes of different apertures. Cell counting kit-8 (CCK-8) assay was used to detect cell proliferation. Alkaline phosphatase (ALP) activity assay was used to test ALP activity. The expression of related osteogenic genes was tested by real-time PCR. The adhesion and growth of BMSCs were investigated by scanning electron microscopy (SEM) and living / dead cell staining. SPSS 22.0 software package was used for statistical analysis of the results. RESULTS: The results of 3D-printing Ti-meshes tension and compression loading experiment were excellent. The 3D-printing Ti-meshes showed no inhibitory effects on cell proliferation, survival and adhesion, but had a positive effect on osteogenesis of BMSCs. CONCLUSIONS: The mechanical properties of 3D-printed Ti-meshes are excellent. The 3D-printed Ti-meshes have good biocompatibility.

Effect and Mechanism of Survivin on Hypoxia-Induced Multidrug Resistance of Human Laryngeal Carcinoma Cells.

This study aimed at clarifying the mechanism and role of survivin in hypoxia-induced multidrug resistance (MDR) of laryngeal carcinoma cells. Human laryngeal cancer cells were incubated under hypoxia or normoxia. The expression of survivin was silenced by performing RNA interference. Additionally, by Western blot and real-time quantitative RT-PCR, survivin expression was detected. The sensitivity of human laryngeal carcinoma cells to multiple drugs was measured by CCK-8 assay. Meanwhile, the apoptosis of cells induced by cisplatin or paclitaxel was assessed by Annexin-V/propidium iodide staining analysis. Under hypoxic conditions, the upregulation of survivin was abolished by RNA interference. Then, CCK-8 analysis demonstrated that the sensitivity to multiple agents of laryngeal carcinoma cells could be increased by inhibiting survivin expression (P < 0.05). Moreover, Annexin-V/propidium iodide staining analysis revealed that decreased expression of survivin could evidently increase the apoptosis rate of laryngeal carcinoma cells that were induced by cisplatin or paclitaxel evidently (P < 0.05). Our data suggests that hypoxia-elicited survivin may exert a pivotal role in regulating hypoxia-induced MDR of laryngeal cancer cells by preventing the apoptosis of cells induced by chemotherapeutic drug. Thus, blocking survivin expression in human laryngeal carcinoma cells may provide an avenue for gene therapy.

Lactoferrin ameliorates aging-suppressed osteogenesis via IGF1 signaling.

Lactoferrin (LF) is an iron-binding glycoprotein that plays an important role in promoting bone formation and inhibiting bone resorption; however, its effects on senile osteoporosis remain unknown. This study aimed to investigate the effects and mechanism of LF intervention using a senile osteoporosis model (SAMP6 mice) and senescent osteoblasts. Micro-CT and hematoxylin and eosin staining demonstrated that the intragastric administration (2 g/kg/day) of LF could improve the bone mass and microstructure of SAMP6 mice. Furthermore, LF treatment improved bone metabolism and increased insulin-like growth factor 1 (Igf1) mRNA expression and activated phosphorylation status of AKT. Using osteoblasts passaged for ten generations as an in vitro senescence model, various markers associated with osteoblast formation and differentiation, as well as related indices of oxidative stress were analyzed. Our results revealed that after multiple generations, osteoblasts entered senescence, in conjunction with increased oxidative stress damage, reduced bone metabolism and enhanced expression of aging-related markers. While inhibiting oxidative stress, LF improved osteoblast proliferation by promoting the expression of osteogenesis markers, including alkaline phosphatase (ALP) activity, Igf1, bone gla protein (Bglap) and osteoprotegerin/receptor activator of nuclear factor-kB ligand (Opg/Rankl) mRNA and delayed senescence by decreasing the level of p16 and p21 expression. RNAI-mediated downregulation of IGF1 attenuated the effect of LF on osteogenesis. Therefore, the findings of the present study indicate that LF may promote osteogenesis via IGF1 signaling, thereby preventing senile osteoporosis.

Ternary Organic Solar Cells with Coumarin7 as the Donor Exhibiting Greater Than 10% Power Conversion Efficiency and a High Fill Factor of 75.

Ternary bulk heterojunction (BHJ) is a brilliant photovoltaic technology for improving the performance of organic solar cells (OSCs), because the light absorption range can be significantly extended by using multiple donors or acceptor materials. In this paper, coumarin7 (C7), a small organic molecule typical led used in organic light-emitting diodes, was initially exploited as second electron-donor component in ternary bulk heterojunction OSCs along with conventional blend system spolythieno[3,4-b]-thiophene/benzodithiophene(PTB7) and [6,6]-phenyl-C71 -butyric acid methyl(PC71 BM). A champion PCE value of 10.28% was realized in the ternary OSCs when incorporated with 10 wt % C7 doping ratio in the donors, corresponding to about 35% enhancement compared with the PTB7:PC71BM-based OSCs, a high fill factor (FF) of 75.03%, a short-circuit currentdensity (Jsc) of 18.72 mA cm-2 and an open-circuit voltage (Voc) of 0.73 V. The enhanced performance of the ternary OSCs can be attributed to the simultaneous improvement of the FF and the Jsc. In addition to extended light absorption, a perfect nanofiber filament active layer morphology is obtained due to the good compatibility between C7 and PTB7, which facilitates the balance of charge transportation and the suppression of charge recombination. This investigation suggests that coumarin derivatives, which have completely different structure with polymer donors, can also be used to fabricate ternary solar cells and have the potential applications to obtain amazing performance after further device engineering and optimization.

Oxymatrine downregulates HPV16E7 expression and inhibits cell proliferation in laryngeal squamous cell carcinoma Hep-2 cells in vitro.

OBJECTIVE: To investigate the possible mechanisms of oxymatrine's role in anti laryngeal squamous cell carcinoma. METHODS: We examined the effects of oxymatrine on the proliferation, cell cycle phase distribution, apoptosis, and the protein and mRNA expression levels of HPV16E7 gene in laryngeal carcinoma Hep-2 cells in vitro. The HPV16E7 siRNA inhibition was also done to confirm the effect of downregulating HPV16E7 on the proliferation in Hep-2 cells. RESULTS: Oxymatrine significantly inhibited the growth and proliferation of Hep-2 cells in a dose-dependence and time-dependence manner. Oxymatrine blocked Hep-2 cells in G0/G1 phase, resulting in an obvious accumulation of G0/G1 phase cells while decreasing S phase cells. Oxymatrine induced apoptosis of Hep-2 cells, whose apoptotic rate amounted to about 42% after treatment with 7 mg/mL oxymatrine for 72 h. Oxymatrine also downregulated the expression of HPV16E7 gene, as determined by the western blotting and reverse transcription-polymerase chain reaction analysis. Knockdown of HPV16E7 effectively inhibited the proliferation of Hep-2 cells. CONCLUSIONS: Oxymatrine inhibits the proliferation and induces apoptosis of laryngeal carcinoma Hep-2 cells, which might be mediated by a significant cell cycle arrest in G0/G1 phase and downregulation of HPV16E7 gene. Oxymatrine is considered to be a likely preventive and curative candidate for laryngeal cancer.

Hypoxia induced multidrug resistance of laryngeal cancer cells via hypoxia-inducible factor-1α.

OBJECTIVES: To investigate whether hypoxia has an effect on regulation of multidrug resistance (MDR) to chemotherapeutic drugs in laryngeal carcinoma cells and explore the role of hypoxia-inducible factor-1α (HIF- 1α). METHODS: Laryngeal cancer cells were cultured under normoxic and hypoxic conditions. The sensitivity of the cells to multiple drugs and levels of apoptosis induced by paclitaxel were determined by MTT assay and annexin-V/propidium iodide staining analysis, respectively. HIF-1α expression was blocked by RNA interference. The expression of HIF-1α gene was detected by real-time quantitative RT-PCR and Western blotting. The value of fluorescence intensity of intracellular adriamycin accumulation and retention in cells was evaluated by flow cytometry. RESULTS: The sensitivity to multiple chemotherapy agents and induction of apoptosis by paclitaxel could be reduced by hypoxia (P<0.05). A the same time, the adriamycin releasing index of cells was increased (P<0.05). However, resistance acquisition subject to hypoxia in vitro was suppressed by down-regulating HIF-1α expression. CONCLUSION: HIF-1α could be considered as a key regulator for mediating hypoxia-induced MDR in laryngeal cancer cells via inhibition of drug-induced apoptosis and decrease in intracellular drug accumulation.

Expression and significance of hypoxia-inducible factor-1α and MDR1/P-glycoprotein in laryngeal carcinoma tissue and hypoxic Hep-2 cells.

The present study aimed to evaluate the expression of hypoxia-inducible factor-1α (HIF-1α) and MDR1/P-glycoprotein (P-gp) in human laryngeal squamous cell carcinoma (LSCC) tissues, and also to investigate the regulation of MDR1 gene expression by HIF-1α in Hep-2 cells under hypoxic conditions. The expression of HIF-1α and MDR1/P-gp in human LSCC tissues was examined using immunohistochemistry. The HIF-1α and MDR1 gene expression in the Hep-2 cells was detected using real-time quantitative reverse transcription (QRT)-PCR and western blot analysis under normoxic and hypoxic conditions. In hypoxia, HIF-1α expression was inhibited by RNA interference. HIF-1α and MDR1/P-gp expression was high in the LSCC tissues and was associated with the clinical stage and lymph node metastasis (P<0.05). HIF-1α expression was positively correlated with MDR1/P-gp expression (P<0.01). In the Hep-2 cells, HIF-1α and MDR1/P-gp expression significantly increased in response to hypoxia. The inhibition of HIF-1α expression synergistically downregulated the expression of the MDR1 gene in hypoxic Hep-2 cells. HIF-1α expression is positively correlated with MDR1/P-gp expression in LSCC, and the two proteins may be able to serve as potential biomarkers for predicting the malignant progression and metastasis of LSCC. HIF-1α may be critical for the upregulation of MDR1 gene expression induced by hypoxia in Hep-2 cells.

Gene and microRNA expression reveals sensitivity to paclitaxel in laryngeal cancer cell line.

Paclitaxel is a widely used chemotherapy drug for advanced laryngeal cancer patients. However, the fact that there are 20-40% of advanced laryngeal cancer patients do not response to paclitaxel makes it necessary to figure out potential biomarkers for paclitaxel sensitivity prediction. In this work, Hep2, a laryngeal cancer cell line, untreated or treated with lower dose of paclitaxel for 24 h, was applied to DNA microarray chips for gene and miR expression profile analysis. Expression of eight genes altered significantly following paclitaxel treatment, which was further validated by quantitative real-time PCR. Four up-regulated genes were ID2, BMP4, CCL4 and ACTG2, in which ID2 and BMP4 were implicated to be involved in several drugs sensitivity. While the down-regulated four genes, MAPK4, FASN, INSIG1 and SCD, were mainly linked to the endoplasmic reticulum and fatty acid biosynthesis, these two cell processes that are associated with drug sensitivity by increasing evidences. After paclitaxel treatment, expression of 49 miRs was significantly altered. Within these miRs, the most markedly expression-changed were miR-31-star, miR-1264, miR-3150b-5p and miR-210. While the miRs putatively modulated the mRNA expression of the most significantly expression-altered genes were miR-1264, miR-130a, miR-27b, miR-195, miR-1291, miR-214, miR-1277 and miR-1265, which were obtained by miR target prediction and miRNA target correlation. Collectively, our study might provide potential biomarkers for paclitaxel sensitivity prediction and drug resistance targets in laryngeal cancer patients.

[Polychaete community in mangrove and salt marsh in Zhangjiang River Estuary, Fujian Province of East China].

In order to understand the community structure of polychaete in different botanic habitats in Zhangjiang River Estuary, an investigation was conducted in the habitats of Kandelia candel, Aegiceras corniculatum, Spartina alterniflora, and Avicennia marina in four seasons, 2010. A total of 15 polychaete species were recorded, and 6 species including Eteone delta, Namalycastis abiuma, Paraleonnates uschakovi, Polydora ciliata, Capitella capitata, and Mediomastus californiensis were found in the four habitats and four seasons. The density, biomass, richness index, evenness index, and diversity index of the polychaete had no significant differences among seasons but significant differences among habitats, and the dominant species of polychaete in S. alterniflora habitat differed from that in the other three mangrove habitats. Pearson correlation analysis showed that in the mangrove and salt marsh, there were no significant correlations between the polychaete parameters (density, biomass, richness index, evenness index, and diversity index) and the environmental factors (sediment temperature, salinity, total organic carbon, and total nitrogen), except that the species number of polychaete had significant correlation with sediment temperature due to the common species of polychaete such as Capitella capitata, Mediomastus californiensis, and Namalycastis abiuma in the mangrove and salt marsh in Zhangjiang River Estuary being of eurytherm and eurysalinity, and resistant to high organic matter content.

[Secondary productivity of macrobenthos in mangrove and salt marsh in Gaoqiao of Zhanjiang, Guangdong Province of South China].

In order to understand the secondary productivity of macrobenthos in different botanic habitats in intertidal zone in Gaoqiao of Zhanjiang, the Brey's empirical formula was applied to calculate the secondary productivity based on the investigations in the habitats of Sonneratia apetala, Aegiceras corniculatum, Sporobolus virginicus, and Bruguiera conjugate in four seasons, 2010. The secondary productivity of the macrobenthos in the habitats in four seasons was averagely 11.77 g AFDM x m(-2) x a(-1), being the highest in S. apetala habitat (18.16 g AFDM x m(-2) x a(-1)), followed by in A. corniculatum habitat (17.67 g AFDM x m(-2) x a(-1)), S. virginicus habitat (8.34 g AFDM x m(-2) x a(-1)), and B. conjugate habitat (2.92 g AFDM x m(-2) x a(-1)). The P/B ratio of the macrobenthos was the highest in B. conjugate habitat (2.38), followed by in S. virginicus, S. virginicus, and A. corniculatum habitats, with the values of 1.23, 0.99, and 0.48, respectively. The differences in the secondary productivity and P/B ratio of the macrobenthos among the four botanic habitats were mainly related to the sediment total organic carbon, food type, and macrobenthos individual size.

[Modified frontolateral partial larnygectomy without tracheostomy for early laryngeal cancer of the true vocal cord].

OBJECTIVE: To investigate the feasibility of modified frontolateral partial laryngectomy without tracheostomy in the treatment for early laryngeal cancer or severe atypical hyperplasia of the true vocal cord. METHODS: A retrospective analysis of 41 patients treated in the past 6 years with modified frontolateral partial laryngectomy without tracheostomy was carried out. There were 39 early laryngeal cancers of the lateral vocal cord with 34 in T1a stage and 5 in T2, and the remain 2 patients had severe atypical hyperplasia of the lateral vocal cord. An ipsilateral false vocal cord flap was used in 39 patients and cervical skin flap in 2 to reconstruct the defect after resection of the true vocal cord. In order to get a large laryngeal cavity, a reverted sternohyoid fascia was used to cover the front area, which made the new laryngeal lumen become ladder-shaped. RESULTS: The incisions of all 41 patients healed up by first intention. The only postoperative complication was subcutaneous emphysema, which developed postoperatively in 9 patients, but subsided prior to discharge. The estimated 1-, 3- and 5-year survival rates were all 100%. No patients died during the postoperative period. CONCLUSION: Modified frontolateral partial laryngectomy without tracheostomy is effective with a high rate of success in eradicating early or selected invasive glottic squamous cell carcinoma or severe atypical hyperplasia of the true vocal cord.

[Effects of risperidone on polysomnography in patients with first-episode schizophrenia].

OBJECTIVE: To investigate the effects of risperidone on the polysomnography (PSG) in the patients with first-episode schizophrenia. METHODS: Twenty-five patients with first-episode schizophrenia, 13 males and 12 females, aged 29 +/- 8, underwent polysomnographic recording for 4 consecutive nights, the first night being used for acclimatization, and on the 3 rd and 4 th nights risperidone in the dose of 1.2 mg was administered before going to bed. Forty-four healthy persons, 23 males and 21 females, aged 28 +/- 8, underwent polysomnographic recording for 2 consecutive nights, the first night being used for acclimatization. RESULTS: The baseline PSG recording showed that in comparison with the normal control group the total sleep time of the schizophrenia patients was shorter (378 min +/- 30 min vs 462 min +/- 21 min), sleep latency was longer (30 min +/- 14 min vs 18 min +/- 8 min), rapid eye movement (REM) sleep latency was shorter (59 min +/- 20 min vs 88 min +/- 10 min), REM sleep time was shorter (61 min +/- 17 min vs 84 min +/- 12 min), awakening time was longer (34 min +/- 17 min vs 15 min +/- 5 min), stage 1 (S1) time was longer (22% +/- 10% vs 9.0% +/- 1.7%), S3 time and S4 time were shorter, and the sleep efficacy was lower (86% +/- 10%) (P < 0.05 approximately P < 0.01); however, there was no significant difference in the S2 time between these 2 groups (54% +/- 16% vs 56% +/- 4%, P > 0.05). In the schizophrenia group, in comparison with the baseline levels in the third and fourth nights the total sleep times were significantly increased (406 min +/- 34 min and 428 min +/- 31 min respectively), the awakening times were significantly decreased (23 min +/- 15 min and 19 min +/- 8 min respectively), and S1 times were significantly decreased (14 min +/- 9 min and 10 min +/- 9 min respectively), with such changes time-dependently; and in the 4 th night the REM sleep time was significantly increased (87 min +/- 20 min) and the sleep efficacy was significantly improved (93% +/- 12%) (P < 0.05 approximately P < 0.01), however, there were no significant differences in the sleep latency and slow wave sleep (both P > 0.05). CONCLUSION: Risperidone significantly improves the quality of sleep.

[Surgery on laryngeal carcinoma--retrospective analysis of 205 cases].

OBJECTIVE: To evaluate the results of surgery for laryngeal carcinoma. METHODS: A retrospective analysis of long-term therapeutic effect was made on surgery of 105 patients with laryngeal carcinoma in the past 15 years. There were 197 males, 8 cases of female. Tumor stage were included 3 cases of Tis NOMO, 45 cases of T1NOM0, 1 case of T1N1M0, 88 cases of T2NOM0, 3 cases of T2N1M0, 1 case of T2N2M0, 33 cases of T3NOM0, 7 cases of T3N1M0, 3 cases of T3N2M0, 13 cases of T4NOM0, 6 cases of T4N1M0, 1 case of T4N2M0 and 1 case of T4N3M0. Different kinds of operations were as follows: cordectomy (1 case) or stripping (2 cases) by suspended laryngoscope, laryngofissure (9 cases), vertical partial laryngectomy without tracheotomy (16 cases), vertical partial laryngectomy (25 cases), horizontal laryngectomy (7 cases), Arslan's procedure (15 cases), cricohyoidoepiglottopexy (57 cases), subtotal laryngectomy (16 cases) and total laryngectomy (57 cases). RESULTS: There were only four missing cases among all 205 cases. The 3- and 5-year survival rate for glatt and carcinoma is 91.3% and 84. 7% respectively. The 3- and 5-year survival rate for supraglottic carcinoma is 67.5% and 65.0% respectively. Statistical differences were noted between survival rate of glottic and supraglottic carcinoma and between early and advantage disease. The overall 3- and 5-year survival rate is 84.8% and 79.4% respectively. The rate of surgical preservation of laryngeal function is 72.7%. CONCLUSIONS: The prognosis factors of laryngeal cancer were tumor stage, subsite, neck metastasis. All patients treated with different surgical techniques had fairly good quality of functional results. It is possible to preserve the laryngeal function by proper indication, safe margin, combined radiotherapy without compromising survival.

[Sensory gating of patients with first-episode schizophrenia].

OBJECTIVE: To investigate the characteristics of sensory gating P50 of patients with first-episode schizophrenia. METHODS: The auditory evoked potentials P50 were recorded in 66 patients (Group Sch) with first-episode schizophrenia and 92 normal controls (Group NC) by using conditioning/testing paradigm presented with auditory double click stimuli. RESULTS: The value of S1-P50 of Group Sch was 3 microV +/- 2 microV, significantly lower than that of Group NC (6 microV +/- 3 microV, P <0.01). The value of S2-P50 of Group Sch was 4 microV +/- 2 microV, significantly higher than that of Group NC (2 microV +/- 1 microV, P < 0.01). The S2/S1 ratio of Group Sc was 81% +/- 40%, significantly higher than that of Group NC (42% +/- 21%, P < 0.01). The value of S2 - S1 of Group Sch was 2 microV +/- 1 mciroV, significantly lower than that of Group Sch (3 mciroV +/- 2 microV). The value of 100 (1-S2/S1) of Group Sch was 19% +/- 17%, significantly lower than that of Group NC (58% +/- 21% , P < 0.01). CONCLUSION: Sensory gating deficit exists in the patients with first-episode schizophrenia, manifested in deficiency of inhibition that can be quantitatively observed by measuring auditory evoked potential P50.