Objective:To explore the obliteration of the old mastoid cavity and reconstruction of the posterior canal wall after radical mastoidectomy. Method:Posterior canal wall reconstruction and mastoid obliteration of 11 ears of 10 patients with old mastoid cavity for 1 to 6 years after radical mastoidectomy were done using the pedicle postauricular composite skin flap (PPCSF),and their tympanoplasty were performed at the same time. Follow-up was performed at 3 to 30 months. Result:All PPCSFs survived. The old mastoid cavity of 11 ears vanished and reconstructed posterior canal wall remained in normal position without retraction. The drying ear time took 2 to 3 weeks postoperatively,and the symptoms of the radical cavity disease after radical mastoidectomy were cleared up nearly,and the average hearing threshold decreased 13.6 dB HL. The otorrhea and perforation of tympanic membrane resulted from infection happened to 1 of 11 ears three month after the operation. Conclusion: The PPCSF is an effective method in the obliteration of old mastoid cavity and reconstruction of the posterior canal wall. It can reduce drying ear time postoperatively, treat the radical cavity disease after radical mastoidectomy and is beneficial to the tympanoplasty at the posterior external at the same time.

AIM:?To?investigate?if?alfentanil?protects?the?isolated?rat?heart?against?myocardial?reperfusion?injury?and?if?the?mechanism?of?this?protection?is?mediated?via?opioid?receptors?and?NO-dependent?pathways. METHODS: Langendorff rat hearts were perfused at constant pressure with Kreb-Henseleit(K-H) buffer for 20 min?and?then?were?perfused?with?test?solution:?K-H?buffer?or?K-H?buffer?containing?alfentanil? 50 ?g?L -1,?alfentanil? 100 ?g?L -1, naloxone 200 ?g?L -1, alfentanil 100 ?g?L -1+naloxone 200 ?g?L -1, L-NAME 100 ?mol?L -1 and alfentanil 100 ?g?L -1+L-NAME 100 ?mol?L -1. After 10 min of this, the hearts were subjected to 25 min normothermic( 37 ℃) global ischemia followed by 30 min reperfusion with the same test solution as before. To evaluate myocardial function, LVEDP, LVDP, ?dp/dt max, HR and CF were measured at the 20th, 25 and 30th minute of perfusion and the 1st, 3rd, 5th, 10th, 20th and 30th minute of reperfusion. After experiment, the NOS and ATP content of myocardium were assessed. RESULTS: Before ischemia, alfentanil 100 ?g?L -1 decreased the HR at the 30th minute compared with the 20th minute(P

BACKGROUND: Foreign studies have demonstrated that the blue light at 470 nm inhibits melatonin secretion and displays the most obvious biorhythm regulation. To date, light-emitting diode (LED) applied in regulating biorhythm remains poorly explored. OBJECTIVE: To explore whether a certain intensity of LED (blue) light could induce retinal injury in rats. DESIGN, TIME AND SETTING: Randomized, controlled animal experiment was performed at the Animal Laboratory of Peking University Third Hospital between May 2007 and April 2008. MATERIALS: A total of 32 SD rats and 16 BN rats were provided by Animal Department of Peking University Third Hospital. METHODS: A total of 16 SD and 16 BN rats were respectively randomly divided into test and control groups. Test group rats were placed in light boxes which were controlled by blue LED (wavelength 470 nm) at a intensity of 300-350μW/cm2, 4 hours everyday for 3 days. The remaining SD rats were placed in light box which was controlled by blue LED (wavelength 470 nm) at a intensity of 120-150μW/cm2, 4 hours everyday for 3 days. The control rats were not treated. MAIN OUTCOME MEASURES: At the second day after light irradiation, the rats of all groups were sacrificed and both eyeballs were harvested. The frozen sections were subjected to hematoxylin-eosin staining to observe changes of rat retina. RESULTS: A total of 48 rats were included in final analysis. The retina of SD rats became thinning and disorderly arranged following blue LED irradiation at density of 300-350μW/cm2, but the retina of BN rat remained unchanged similar to control group. After blue LED irradiation at density of 120-150μW/cm2, the retina of SD rat remained unchanged similar to control group. CONCLUSION: Blue LED light source irradiation at a intensity of 300-350μW/cm2 is safe to pigment-protected retina, and at a intensity of 120-150μW/cm2 does not injury retina of different races of rats.

OBJECTIVE To evaluate the effects of arsenic trioxide (As2O3) on the cell cycle and microfilament cytoskeleton in human nasopharyngeal carcinoma cell line(CNE1),as well as possible mechanisms. METHODS The variation of cell cycle and microfilament cytoskeleton in CNE1 were observed using the flow cytometry (FCM),the laser scanning confocal microscopy(LSCM)and technology of fluorescence.RESULTS FCM showed that the proportion of G1 phase cells significantly increased in cells exposed to 2 and 4?mol/L As2O3(P

OBJECTIVE: To explore the treatment effect of selective neurotomy of anterior ethmoid nerve and squeezing operation of inferior turbinate in the treatment of perennial allergic rhinitis (PAR). METHOD: Seventy cases of perennial allergic rhinitis were selected and subjected to selective neurotomy of anterior ethmoid nerve and squeezing operation of inferior turbinate,and the treatment effect was observed by analysis of the the symptoms and signs score of all cases preoperatively and postoperatively. RESULT: The total effective rate were 90.0% at 1 year follow-up. CONCLUSION Selective neurotomy of anterior ethmoid nerve and squeezing operation of inferior turbinate were effective for the patients with PAR. It is worthy to be popularized for its convent and rare complications.
Adolescent ; Adult ; Denervation ; methods ; Ethmoid Bone ; innervation ; Female ; Humans ; Male ; Middle Aged ; Rhinitis, Allergic, Perennial ; surgery ; Turbinates ; surgery ; Young Adult

Objective: To investigate the features of literature on hand-transmitted vibration in China, 1990-2016. Methods: In September 2017, the studies on hand-transmitted vibration in China, which were published in Chinese or English during 1990-2016, with "China" and "Taiwan" as the places where author affiliations were located, were retrieved. A bibliometric analysis was performed to investigate the type of articles, publication time, the journals in which articles were published, author affiliations, author regions, and funding. Results: A total of 205 articles on hand-transmitted vibration were retrieved. There were 7.59 articles on average published annually from 1990 to 2016. In the 205 articles, 114 (55.61%) were published in the journals indexed in one or two core journal databases. In the 64 journals, 22 (34.38%) were indexed in one or two core journal databases. The first authors were from 22 provincial regions (provinces, autonomous regions, or centrally administered municipalities) in China, with 152 articles (74.15%) by the authors in the top five regions. There were a total of 876 authors, and the co-authorship degree was 4.27 (876/205). Most of the first authors (136 articles, 66.34%) were affiliated with universities or institutes for prevention and control of occupational diseases. Among the 205 articles, 103 (50.24%) were original articles or investigations, and 72 (35.12%) were funded. Conclusion The studies on hand-transmitted vibration fluctuated and increased from 1990 to 2016, with a relatively concentrated distribution in terms of sources, regions, and institutions. Interregional and international academic exchange should be strengthened.

Objective: To study the correlation between low back pain (LBP) and occupational stress in coal miners. Methods: From January 2015 to December 2016, a total of 472 front-line workers in a mining area of a large-scale coal mining enterprise in Shanxi, China were enrolled in the study. The general information, condition of LBP, and occupational stress level of the subjects were obtained by questionnaire survey. Dichotomous logistic regression (DLR) was used to analyze the correlation between LBP and occupational stress. Results: Of the 472 subjects, 186 subjects experienced LBP in the past year; the prevalence rate of LBP was 39.41%. The scores of the Occupational Role Questionnaire were significantly higher for workers in the LBP group than in the non-LBP group (P<0.01) . As revealed by the DLR analysis, age, marital status, length of service, occupational stress role, labor intensity, keeping single posture during work, and working in shifts were risk factors of LBP (P<0.01) , while smoking may be a protective factor against LBP (P<0.01) . Conclusion Occupational stress role is a potential risk factor for LBP in coal miners (P<0.01) . Reasonable work assignment and timely alleviation of occupational stress may be one of the effective approaches to prevent LBP.

BACKGROUND: Corneal disease is second only to cataract considered as the leading cause of blindness in the world, with high morbidity. Construction of corneal substitutes In Vitro by tissue engineering technology to achieve corneal regeneration has become a research hotspot in recent years. We conducted in-depth research on the biocompatibility, physicochemical and mechanical properties of rat bone marrow mesenchymal stem cells (rBM-MSCs)-seeded gelatin methacrylate (GelMA) as a bioengineered cornea. METHODS: Four kinds of GelMA with different concentrations (7, 10, 15 and 30%) were prepared, and their physicchemical, optical properties, and biocompatibility with rBM-MSCs were characterized. MTT, live/dead staining, cell morphology, immunofluorescence staining and gene expression of keratocyte markers were performed. RESULTS: 7%GelMA hydrogel had higher equilibrium water content and porosity, better optical properties and hydrophilicity. In addition, it is more beneficial to the growth and proliferation of rBM-MSCs. However, the 30%GelMA hydrogel had the best mechanical properties, and could be more conducive to promote the differentiation of rBM-MSCs into keratocyte-like cells. CONCLUSION As a natural biological scaffold, GelMA hydrogel has good biocompatibility. And it has the ability to promote the differentiation of rBM-MSCs into keratocyte-like cells, which laid a theoretical and experimental foundation for further tissue-engineered corneal stromal transplantation, and provided a new idea for the source of seeded cells in corneal tissue engineering.

OBJECTIVE： To study the mechanism of Prunus persica-Carthamus tinctorius couplet medicine in the treatment of osteonecrosis of the femoral head （ONFH）. METHODS： The network pharmacology was adopted. The active components of P. persica -C. tinctorius couplet medicine and ONFH target were screened through TCM systematic pharmacological analysis platform target （TCMSP）， DRAR-CPI， hnuman gene database （GeneCards） and online medelian inheritance in man （OMIM） using oral availability of compounds （OB）＞30％ and drug like （DL）＞0.18 as standard. Network topology attribute analysis software Cytoscape 3.6.0 was utilized to construct the active components-ONFH targets network. Target protein interaction network was established on the basis of STRING database， and top 5 target proteins in the list of connectivity were screened， and molecular docking server was used to predict the combination activity of active components from P. persica -C. tinctorius couplet medicine. The biological processes of target gene ontology （GO） and metabolic pathways in Kyoto encyclopedia of genes and genomes （KEGG） were enriched and analyzed by DAVID. RESULTS： A total of 44 active components were screened from P. persica -C. tinctorius couplet medicine， including baicalin， quercetin， etc.， and 78 targets related to ONFH including VEGF， VEGI， CRP， etc. Through analysis of molecular docking server， binding activity of active components of P. persica -C. tinctorius couplet medicine to target protein was strong. GO and KEGG pathway enrichment analysis showed that biological process of P. persica -C. tinctorius couplet medicine for ONFH was related with negative regulation of apoptosis process and positive regulation of nuclear factor-κB transcription factor， mainly through regulating secretory glycoprotein signaling pathway， melanogenesis signaling pathway， VEGF signaling pathway， signaling pathway of basal cell carcinoma， adenosine-activated protein kinase signaling pathway. CONCLUSIONS： This study preliminarily validates the major targets and pathways of P. persica -C. tinctorius couplet medicine for ONFH， which lay a foundation for further study on their pharmacological action.

Carbon nanotube (CNT) composite materials are very attractive for use in neural tissue engineering and biosensor coatings. CNT scaffolds are excellent mimics of extracellular matrix due to their hydrophilicity, viscosity, and biocompatibility. CNTs can also impart conductivity to other insulating materials, improve mechanical stability, guide neuronal cell behavior, and trigger axon regeneration. The performance of chitosan (CS)/polyethylene glycol (PEG) composite scaffolds could be optimized by introducing multi-walled CNTs (MWCNTs). CS/PEG/CNT composite scaffolds with CNT content of 1%, 3%, and 5% (1%=0.01 g/mL) were prepared by freeze-drying. Their physical and chemical properties and biocompatibility were evaluated. Scanning electron microscopy (SEM) showed that the composite scaffolds had a highly connected porous structure. Transmission electron microscope (TEM) and Raman spectroscopy proved that the CNTs were well dispersed in the CS/PEG matrix and combined with the CS/PEG nanofiber bundles. MWCNTs enhanced the elastic modulus of the scaffold. The porosity of the scaffolds ranged from 83% to 96%. They reached a stable water swelling state within 24 h, and swelling decreased with increasing MWCNT concentration. The electrical conductivity and cell adhesion rate of the scaffolds increased with increasing MWCNT content. Immunofluorescence showed that rat pheochromocytoma (PC12) cells grown in the scaffolds had characteristics similar to nerve cells. We measured changes in the expression of nerve cell markers by quantitative real-time polymerase chain reaction (qRT-PCR), and found that PC12 cells cultured in the scaffolds expressed growth-associated protein 43 (GAP43), nerve growth factor receptor (NGFR), and class III β‍-tubulin (TUBB3) proteins. Preliminary research showed that the prepared CS/PEG/CNT scaffold has good biocompatibility and can be further applied to neural tissue engineering research.
Animals ; Axons ; Biocompatible Materials/chemistry* ; Chitosan/chemistry* ; Nanotubes, Carbon/chemistry* ; Nerve Regeneration ; Polyethylene Glycols ; Porosity ; Rats ; Tissue Engineering/methods* ; Tissue Scaffolds/chemistry*