Effect of surface modification on biotribological properties of ultra-high molecular weight polyethylene artificial joints / 中国骨伤

Friction and wear of ultra-high molecular weight polyethylene is a major cause of artificial joint failure. According to mechanism of surface modification method, friction reduction and wear-resistance properties of UHMWPE were improve by several kinds of surface modification methods. Meanwhile, this do not damage the internal structure and properties of UHMWPE. In the process, condition is easy to control and operation is simple. However, reaction time of radiation crosslinking method is too long, the material will be oxidized embrittlement; Monomer itself homopolymerization are seriously in the process of surface grafting; The injection layer of ion implantation methods is very thin and easy to be destroyed. Objective in order to provide a reference for further research on the biotribological properties of ultra-high molecular weight polyethylene artificial joints. At present, as the researches of UHMWPE material main focus on abrasion resistance, and application in the clinical trial is the focus of research, it has a wide prospect in the future.

Research on repair strategies for articular cartilage defects / 中国骨伤

Articular cartilage damage is very common in clinical practices. Due to the low self-healing abilities of articular cartilage, the repair strategies for articular cartilage such as arthroscopic lavage and debridement,osteaochondral or chondrocytes transplantation, tissue engineering and hydrogel based artificial cartilage materials are the primary technologies of repairing articular cartilage defect. In this paper,the main repair strategies for the articular cartilage damage and the advantages or disadvantages of each repair technology are summarized. The arthroscopic lavage and debridement is successful in treating the early stage of osteoarthritis. Osteochondral and chondrocytes transplantation are beneficial to treat small full thickness defects. The technology of tissue engineering becomes a new method to heal articular cartilage damage, but the major problem is the absence of bonding strength between the implants and natural defect surfaces. Hydrogel based artificial cartilage possesses similar bio-mechanical and bio-tribological performances to that of natural articular cartilage. However, both bioactivity and interfacial bonding strength between the implant and natural cartilage could be further improved. How to simultaneously optimize the mechanical and bioactive as well as biotribological properties of hydrogel based materials is a focus problem concerned.

Clinical analysis of allergic rhinitis in children between 1 and 3 years of age / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To study the atopy spectrum and its related factors in 1 to 3 years old children with allergic rhinitis.</p><p><b>METHODS</b>Ninety-six children with allergic rhinitis, aged between 1 and 3 years old, referred to ENT department of Beijing Children's Hospital between August 2009 and November 2010 were retrospectively reviewed. Data were recorded for patients' age, age stratification, sex, the age of first symptom, the duration of history, and the allergic history of children, the allergic history of parents. The screening tests on inhalant and food allergens were conducted by immunoblot assay using the Allergy Screen system. The total serum IgE level was also measured. The distribution of the inhalant and food allergens was summarized. The influence of the clinical characteristics was analyzed according to the age subgroup determined by month, allergen category and positiveness of eczema or asthma. Logistic regression was used to analyze the relationship of clinical characteristics and allergen spectrum.</p><p><b>RESULTS</b>The total positive rates of allergic screening test rate were 81.3%. The inhalant and food allergens were 62.5% and 53.1% respectively. The commonest allergy was mixed fungal (50.0%), followed by milk (34.4%), lamb (31.3%), beef (26.0%), dust mite (21.0%), wheat (18.8%), mugwort (12.5%), egg white or egg yolk (11.5%).62.5% of patients could be diagnosed as AR, the remaining could be diagnosed temporarily as non-allergic rhinitis temporarily. Single factor analysis of clinical characteristics in different subgroup determined by month showed that: inhalant allergen (positive/negative) (χ2=13.699, P=0.001), father suffered from AR (χ2=14.060, P=0.001), and father or mother suffered from AR (χ2=7.396, P=0.025) were statistically significant at three monthly age groups. The personal history of eczema (OR=3.143, P=0.034) might increase the possibility of sensitization to allergens. The personal history of eczema (OR=3.125, P=0.015) and the total serum IgE level>200 IU/ml (OR=3.119, P=0.030) might increase the possibility of sensitization to inhalant allergens. No clinical features for food allergen sensitization was statistically significant. There was no significant difference in positive rates between inhalant and food allergens groups. The presence of inhalant allergens (OR=3.594, P=0.046), insect bites dermatitis (OR=11.941, P=0.002) were the risk factors for positiveness of eczema or asthma, and the father with AR (OR=0.251, P=0.040) as protective factors.</p><p><b>CONCLUSIONS</b>Inhalant and food allergens all can be sensitized in the children with AR symptoms between 1 to 3 years old, and the positive rate of inhalant group is slightly higher. The differences of the inhalant allergen (positive/negative) and father suffered from AR are statistically significant at three monthly age groups. The history of eczema is the risk factor for allergen screening positive. Serum total IgE>200 IU/ml and eczema history are risk factors for inhalant allergen screening positive. The factors of inhalant allergens, insect bites dermatitis and father suffered from AR relate to any positive of eczema or asthma.</p>

Cryopreservation and resuscitation of neural stem cells from fetal rat / 临床耳鼻咽喉头颈外科杂志

OBJECTIVE@#To explore the survival rate of neural stem cells (NSCs) from fetal rat and its biological properties after cryopreservation and thawing.@*METHOD@#Different generations NSCs (the first generation, the third generation and the sixth generation) from fetal rat which cultivated with serum-free medium in vitro were cryopreserved in the cryogen, which were neurosphere culture medium with 10% BSA and 7.5% DMSO (without neural growth factor). The cryopreserved cells were resuscitated at 1st week, 4th week, 8th week, 12th week and 16th week respectively. The survival rate of cells were calculated and the cells were incubated and differentiated again.@*RESULT@#Different time of cryopreservation, different generations did not affect NSCs survival (P > 0.05) after cryopreservation. The survival rate of NSCs was from 60% to 70% after resuscitated, which were differentiated into neurons and astrocytes in 10% embryonic bovine serum (without growth factor).@*CONCLUSION@#NSCs were successfully cryopreserved, resuscitated and recultured, which would create bases for the experimental study on the selected-date application of NSCs transplantation into cochlea for treating sensorineural deafness.

Impact of RelA antisense oligonucleotides on laryngeal carcinoma Hep-2 cell proliferation / 临床耳鼻咽喉头颈外科杂志

OBJECTIVE@#To study the impacts of RelA antisense oligonucleotides on proliferation in laryngeal carcinoma Hep-2 cell.@*METHOD@#RelA antisense oligonucleotides was designed, which was transferred into laryngeal carcinoma Hep-2 cell. MTT was used to detect the growth-inhibiting ratio at different transferred timepoints. Hep-2 cell which was transferred 48 h was used to do colony assay, and expression of RelA was detected by Reverse Transcription PCR and Western blot.@*RESULT@#MTT results showed that RelA antisense oligonucleotides could significantly suppress the proliferation of Hep-2 cell, and the suppression-ratio elevated with time. There were statistical difference compared with control groups. The number of cells colony was reduced in RelA antisense oligonucleotides group compared with control groups, which had statistic significance. RT-PCR and Western blot results demonstrated that RelA antisense oligonucleotides could significantly inhibit the expression of messenger RNA and protein in Hep-2 cell.@*CONCLUSION@#RelA antisense oligonucleotides can inhibit the expression of messenger RNA and protein, and induce the cell proliferation and increase the number of cells colony in Hep-2 cell.

Expression and significance of IGF-IR and PKC in laryngeal squamous cell carcinoma / 临床耳鼻咽喉头颈外科杂志

OBJECTIVE@#To investigate the expression of IGF-IR and PKC and their clinical significance in laryngeal squamous cell carcinoma(LSCC).@*METHOD@#The expression of IGF-IR and PKC protein were detected by immunohistochemistry and Western blot in 60 cases of LSCC, 25 cases of adjacent non-tumorous laryngeal epithelium and 10 cases of normal laryngeal epithelium.@*RESULT@#The positive rate of IGF-IR and PKC expression in LSCC were significantly higher than that in normal laryngeal epithelium and adjacent non-tumorous laryngeal epithelium (P < 0.05). IGF-IR positive expression were increased more in cases with stage III-IV, cervical lymph node metastasis and well differentiation than that in cases with stage I-II, non-lymph node metastasis and poor/mediate differentiation, respectively (P < 0.05). The positive rate of PKC in LSCC were correlated with clinical stage and cervical lymph node metastasis. There was a correlation between the expression of IGF-IR and PKC in LSCC.@*CONCLUSION@#The overexpression of IGF-IR and PKC in the laryngeal carcinoma may play an important role in the carcinogenesis and development of LSCC. It is suggested that detecting the expression of IGF-IR and PKC can be used for early diagnosis and treatment of LSCC.

Cyclic strain promotes migration of human periodontal ligament cell via extracellular signal-regulated kinase (ERK) signaling pathway / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To study the effect of cyclic strain on migration of human periodontal ligament cell(hPDLC) and underlying mechanism.</p><p><b>METHODS</b>The cultured hPDLC were subjected to 10% or 20%-elongation magnitude cyclic strain at frequency of 0.1 Hz by FX-4000T system for 6 or 24 hours-duration respectively, while the static group serves as control. hPDLC migration was assayed by wound healing method. The expressions of matrix metalloproteinases-9 (MMP-9) and p-ERK1/2 in hPDLC without or with cyclic strain were analyzed by Western blotting. To investigate the effect of ERK signaling pathway and MMP-9 on migration of hPDLC, the cells were incubated with PD98059, a specific extracellular signal-regulated kinase (ERK) kinase inhibitor, or doxycycline, a MMP inhibitor. Then the expressions of p-ERK1/2 and MMP-9 and hPDLC migration were analyzed.</p><p><b>RESULTS</b>In wound healing tests, the migration of hPDLC exposed to 10% or 20%-cyclic strain at 0.1 Hz-frequency for 6 hours was not apparent but became significantly different for 24 hours (P < 0.05) compared to control. Furthermore, the 20%-elongation magnitude of cyclic strain had more remarkable effect on migration of hPDLC than 10%-elongation magnitude at 24 hours-duration (P < 0.05). Cyclic strain obviously increased the expression of MMP-9 in hPDLC (P < 0.05). PD98059 could repress not only the activation of p-ERK1/2 but also the expression of MMP-9 induced by cyclic strain in hPDLC. The migration of hPDLC enhanced by cyclic strain was repressed by DOX or PD98059 in wound healing tests.</p><p><b>CONCLUSIONS</b>Cyclic strain promotes the migration of hPDLC through activating ERK signaling pathway and inducing the expression of MMP-9.</p>

Therapeutic effects of potassium sodium hydrogen citrate on melamine-induced urinary calculi in China / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>In 2008, a sharp increase of the number of children diagnosed with urinary calculi was observed in China, 9433 children were diagnosed as having melamine-induced urinary calculi at outpatient clinic in Beijing Children's Hospital. This study examined the therapeutic efficacy of potassium sodium hydrogen citrate (PSHC) used to treat melamine-induced urinary stones in Chinese children who consumed melamine-containing infant formula.</p><p><b>METHODS</b>Seventy-two infants and children (average age (18.2 +/- 7.7) months) who were diagnosed with urinary calculi were randomly divided into three treatment groups using the SAS Plan program. Group 1 was given a low dose (1 g/d) of PSHC, group 2 was given high dose of PSHC (2 g/d) and group 3 was given no PSHC (control group). The dose of drug was adjusted according to the baseline urinary pH. This study analyzed the influence of the dose of PSHC, the age of patients, stone size and position, and urinary pH on the level of efficacy of PSHC (cured, effectively treated or not cured).</p><p><b>RESULTS</b>After 1 - 6 months of therapy, 19 patients from group 1, five patients from group 2 and six patients from group 3 were cured. Five patients from group 1, five patients from group 2 and four patients from group 3 were effectively treated. There were significant differences in therapeutic efficacy between the two treatment doses after 3 and 6 months as measured by the increase in the successful expulsion rate and time of melamine-induced urinary calculi. After 6 months the mean time of expulsion of urinary calculi in groups 1 and 2 was significantly shorter than in the control group.</p><p><b>CONCLUSIONS</b>PSHC can significantly increase the successful expulsion rate and time of melamine-induced urinary calculi. The therapeutic efficacy is affected by PSHC dose, treatment duration, calculi position, and urinary pH. There is no relationship between the therapeutic efficacy and the stone size or patient age.</p>

Expression and significance of IGF-IR and PKC in laryngeal squamous cell carcinoma / 临床耳鼻咽喉头颈外科杂志

Objective:To investigate the expression of IGF-IR and PKC and their clinical significance in laryngeal squamous cell carcinoma(LSCC).Method:The expression of IGF-IR and PKC protein were detected by immunohistochemistry and Western blot in 60 cases of LSCC, 25 cases of adjacent non-tumorous laryngeal epithelium and 10 cases of normal laryngeal epithelium.Result:The positive rate of IGF-IR and PKC expression in LSCC were significantly higher than that in normal laryngeal epithelium and adjacent non-tumorous laryngeal epithelium(P<0.05). IGF-IR positive expression were increased more in cases with stage Ⅲ-Ⅳ, cervical lymph node metastasis and well differentiation than that in cases with stageⅠ-Ⅱ, non-lymph node metastasis and poor/mediate differentiation, respectively(P<0.05).The positive rate of PKC in LSCC were correlated with clinical stage and cervical lymph node metastasis.There was a correlation between the expression of IGF-IR and PKC in LSCC.Conclusion:The overexpression of IGF-IR and PKC in the laryngeal carcinoma may play an important role in the carcinogenesis and development of LSCC. It is suggested that detecting the expression of IGF-IR and PKC can be used for early diagnosis and treatment of LSCC.

Study on health economics regarding the screening of gastric cancer in Zhuanghe high risk area / 中华流行病学杂志

<p><b>OBJECTIVE</b>Using the health economics methodology to assess the screening program on gastric cancer in Zhuanghe high risk area for gastric cancer, from 2001 to 2003 and to assess the feasibility on cost of the screening program and to provide a basis for the popularization of the two-time gastric cancer screening methodology.</p><p><b>METHODS</b>Three major techniques of medical economics namely cost-effective analysis (CEA), cost-benefit analysis (CBA) and cost-utility analysis (CUA) were used to assess the screening program. The screening program was composed of two steps: (1) epidemiological survey and detection of blood pepsinogen; (2) gastroscopy and biopsy of membrane. 'Number of deaths reduced' was used to evaluate the effect during cost-effective analysis while cost-benefit analysis would include the evaluation on the direct cost and indirect cost, direct benefit and indirect benefit as well as the cost-benefit ratio (CBR). During CUA, a questionnaire of WHOQOL-BREF was used to assess the value of the utility while the number of quality adjusted life year (QALY) saved by the screening program was also computed. The direct cost of per saved QALY was also calculated.</p><p><b>RESULTS</b>Dada from CEA showed that: investing every 8448 Yuan on screening program and treatment in Zhuanghe high risk area of gastric cancer, one gastric cancer patient could be avoided. Results from CBA showed that: direct cost was 1,260,000 Yuan while indirect cost was 40 621 Yuan with direct benefit as 101 500 Yuan and indirect benefit as 1 540 979 Yuan. The total cost however, was 1,300,621 Yuan with total benefit as 2,555,979 Yuan and CBR was 1:1.97. Data from CUA showed that: a total number of 331.44 QALY was saved, 11.43 QALY was saved by reducing one death, 3802 Yuan per QALY was saved in high risk area of gastric cancer, through this screening program.</p><p><b>CONCLUSION</b>The screening program of gastric cancer appeared to be an economic and society-beneficial measure regarding primary prevention in high risk area of gastric cancer. We also suggested that in the future, evaluations through health economics methodologies on different screening programs be carried out in the same population to solve the problem of comparability.</p>

Inhibition of growth and proliferation of Hep-2 cells by targeting human telomerase reverse transcriptase mRNA using RNA interference technology / 中华病理学杂志

<p><b>OBJECTIVE</b>To investigate the effect of RNA interference by targeting human telomerase reverse transcriptase (hTERT) mRNA in the larynx cancer cell line, Hep-2.</p><p><b>METHODS</b>The primary structures of hTERT cDNA were found in GenBank. Then the structure analysis were done according to RNAi strategy which determined the specific base sequences to design shRNA plasmid. Two types of plasmid, pshRNA1 and pshRNA2, involved in fluorescein gene were synthesized based on the specific base sequences. Control pshRNA3, a random sequence, and control pshRNA4, without additional specific sequence were also constructed. Cells were treated daily with pshRNA1-4 or normal culture medium respectively. The pshRNA1-3 was identified by electrophoresis. After administration of pshRNA1-4, fluorescence expression was detected by confocal microscopy, the expression of hTERT of the transfected cells was determined by Western blotting, telomerase activity was measured by TRAP-PCR ELISA, cell viability was determined by MTT assay, morphological changes and apoptosis were examined by inverted microscope and TUNEL respectively.</p><p><b>RESULTS</b>There was a 400 bp balteum in pshRNA1-3 after cut by SalI, which was identical with the size of the objective gene. Many cells presented green fluorescence after being treated by pshRNA1-4, but there are much more dead green fluorescent cells in the pshRNA1 and pshRNA2 group. hTERT protein and telomerase activity was significantly decreased after treated by pshRNA1 or pshRNA2. It was observed that treatment with pshRNA1 or pshRNA2 in the presence of a valid transfection reagent could reduce cell viability of Hep-2 cells within 96 h (P < 0.01). Under the same culture conditions, cells grew more sparsely and the number of apoptotic cell increased significantly.</p><p><b>CONCLUSIONS</b>shRNA plasmid directed against human telomerase reverse transcriptase can effectively transfect Hep-2 cells. shRNA targeted hTERT gene can significantly inhibit the growth and proliferation of Hep-2 cells, which results in apoptotic cell death. RNA interference may be a promising strategy for the treatment of laryngeal cancer.</p>

Cloning and Sequencing of Movement Protein Gene of Cymbidium Mosaic Virus / 中国病毒学

The viral RNA was extracted from purified cymbidium mosa ic virus (CyMV) isolated from Dendrobium orchid cultivated in Hainan island. The gene of the movement protein (MP) was amplified by means of reverse transcripti on-polymerase chain reaction (RT-PCR), and cloned into pGEM-T easy vector. Se quence analysis showed that the gene fragment contained 3 open reading frames (O RFs) which may be encoding 14 kD、12 kD and 10 kD peptides. The nucleotide seque nce of the cloned gene fragment shared 97.8% homology with the MP genes of CyMV isolated from orchids cultivated in Hawaii and Singapore.