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Due to good mechanical properties and biocompatibility, tissue engineering scaffolds have become the vital method for repairing and regenerating articular cartilage defects. With the continuous development of tissue engineering technology, many scaffolds preparation and formation methods have been developed and tested in the past decade, however, the preparation of ideal regenerative scaffolds remain controversial. As load-bearing tissue inside the body joints, the matrix structure and cell composition of articular cartilage are hierarchical, and there are several smooth natural gradients from the cartilage surface to the subchondral bone layer, including cell phenotype and number, specific growth factors, matrix composition, fiber arrangement, mechanical properties, nutrient and oxygen consumption. Therefore, in the design of regenerative scaffolds, it is necessary to achieve these gradients to regenerate articular cartilage in situ. In recent studies, many new biomimetic gradient scaffolds have been used to simulate the natural gradient of articular cartilage. These scaffolds show different mechanical, physicochemical or biological gradients in the structure, and have achieved good repair effects. The related articles on tissue engineering for the treatment of articular cartilage defects were retrieved by searching databases with key wordsarticular cartilage injury, cartilage repair and gradient scaffolds. In this work,the structural, biochemical, biomechanical and nutrient metabolism gradients of natural articular cartilage were studied and summarized firstly. Then, the latest design and construction of articular cartilage gradient scaffolds were classified. Besides that, the material composition (such as hydrogels, nanomaterials, etc.) and the preparation process (such as electrospinning, 3D printing, etc.) of grandient scaffolds were further enhanced. Finally, the prospect and challenge of biomimetic gradient scaffolds in cartilage engineering are discussed, which provides a theoretical basis for the successful application of gradient scaffolds in clinical transformation.
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The treatment of articular cartilage (AC) injury caused by various reasons is still a major clinical problem. The emergence of cartilage tissue engineering brings new hope for the treatment of AC injury. In general, AC tissue engineering can be divided into two categories, including cell-based tissue engineering and cell-free tissue engineering. Although cell-based tissue engineering can repair cartilage damage to a certain extent, existing therapeutic strategies still suffer from limited cell sources, high costs, risk of disease transmission, and complex procedures. However, the cell-free tissue engineering avoids these shortcomings and brings hope for in-situ AC regeneration. Non-cellular tissue engineering is mainly used to recruit endogenous stem cells/progenitor cells (SCPCs) to reach the site of cartilage injury, and provide a suitable regenerative microenvironment to promote cell proliferation and chondrogenic differentiation, then the maturation of new cartilage tissue was promoted. Therefore, it is also called as cell-homing in situ tissue engineering. Successful recruitment of endogenous SCPCs is the first step in in-situ cartilage tissue engineering. This review aims to introduce chemokine response of cartilage injury, systematically summarize traditional chemoattractant (chemokines and growth factors etc.) and emerging chemoattractant (functional peptides, exosomes and nucleic acid adapters etc.), evaluate the combination mode between chemoattractant and delivery devices, discuss the prospects and challenges of chemoattractant-mediated in situ tissue engineering and provide theoretical basis for the design of endogenous SCPCs homing-based in situ tissue engineering.
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Objective:Explore the main measures and operation mechanism to improve the scientific and technological innovation capacity of district and county hospitals by taking advantage of medical consortium, to achieve the goal of targeted poverty alleviation.Methods:Combine the practical exploration and empirical study on the main measures and operating mechanism to improve the scientific and technological innovation capacity of district and county hospitals, pre-and post comparison were conducted to analyze the effectiveness.Results:During the construction of medical consortium, a district-level general hospital has seen obvious increase in the comparison of many achievement indicators of scientific and technological innovation, with the growth rate ranging from 66.67% to 700%.Conclusions:Based on medical consortium, the operation mechanism that takes discipline construction as the starting point and key discipline establishment as the target, Scientific and technological innovation incubation platform, incentive mechanism and regular summary and evaluation can encourage district and county hospitals to improve scientific and technological innovation ability.
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Objective To investigate the role of SIRT1/PGC-1α pathway in the auditory cortex aging of guinea pigs with age-related hearing loss and whether the electroacupuncture can delay aging process of the auditory cortex in the aged guinea pigs induced by D-galactose through the regulation of SIRT1/PGC-1α pathway.Methods Thirty 4-month-old guinea pigs were randomly divided into three groups including the control group (n=10),D-galactose group (model group,n =10),and D-galactose and electroacupuncture group (electroacupuncture group,n =10).The elderly group (n=10) was composed of 18-month-old guinea pigs.The guinea pigs in model group and electroacupuncture group had been subcutaneously injected with D-galactose(300 mg· kg-1· d-1)for 6 weeks.Moreover,the guinea pigs in electroacupuncture group electroacupunctured at Tinggong and Yifeng for 15 minutes half an hour later once a day.After 6 weeks,the ABR threshold of guinea pigs in each group was detected.The mRNA and protein expression of SIR1 and PG-C-1α in auditory cortex of guinea pigs were detected by real -time fluoreacence quantitative PCR and Western Blot.Results There was a significant increase in the ABR threshold of the model group and elderly group (P＜0.001,compared with the control group),decrease in the electroacupuncture group (P＜0.001,compared with the model group),and no significant difference between model group and elderly group(P＞0.05).There was significant decrease in the expression of SIRT1 and PGC-1α in the model groupand elderly group(P＜0.05,compared with the control group),and significant increase at mRNA and protein levels in the electroacupuncture group (P＜0.05,compared with the model group).Conclusion SIRT1/PG-C-1α pathway may play a role in aging process of the auditory cortex in the aged guinea pigs induced by D-galactose,and electroacupuncture at Tinggong and Yifeng may increase the antioxidant capacity of auditory cortex by activating SIRT1/PGC 1α in guinea pigs with age-related hearing loss,thus delaying the aging process of auditory cortex.
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Objective How to make good use of the construction opportunity of the medical association to integrate resources,build scientific research platform and establish practical operation mechanism,to improve the technology innovation ability of district county-level hospitals.Methods Through literature analysis and empirical study,this paper discusses the feasibility and operation mechanism of the construction of research platform in district county-level hospitals.Results The research platform can be built with the help of medical association construction.The operation mechanism can effectively improve the research level of district county-level hospitals,by taking the chance of discipline construction,implementing the institutional mechanism for rewards and punishment.Conclusions With the help of superior medical experts,two-way referral,academic lectures and other activities,advanced scientific culture idea was spread;The training of scientific research personnel,resource integration,and project cooperation increased opportunities.All of this to set up a new platform for district county-level hospitals to promote their scientific and technological innovation abilities.By taking the chance of discipline construction,clarified target responsibility,to carry out the rewards and punishment system and the implementation of the scientific and technological innovation incentive mechanism,can force them to actively promote the ability of scientific and technological innovation,actively carry out scientific research and improve the level of business.
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Objective Investigation and analysis the innovation ability and its influencing factors about graduates in primary hospitals,discuss corresponding measurements to enhance their innovation capacities.Methods A total number of l17master students and leadership persons at related institutions in primary hospitalsfrom particular district of China were surveyed with self-made questionnaires.Transformational Leadership Questionnaire,Organizational Commitment Questionnaire,and Multi dimensional Innovative Behavior Scale were used to investigate both personal and environmental factors that maybe influential for further discussion of possible improvement strategies.Results Among the 117 master students,having a capacity for independent innovationand getting partial achievements is only 6.84％;that canactively participatingin but temporarily have notborne fruit is 11.96％,24.78％ of which are passively finishingthe task of writing papersunder the request of the hospital,high up to 56.41％ are do not have any achievements in technology innovation yet.In the meanwhile,63.16％ administrators,compared to 36.84％,have negative attitudes to the graduate students.In terms of influence factors,that closely related to creative production,creative execution are identity,virtue and the vision of transformational leadership behavior motivation,charismatic leadership,individualized consideration,and affective commitment,ideal commitment,economic commitment,opportunity commitment of organizational commitment,P＜0.05,the difference has statistically significant;but not correlative with normative commitment,P＞0.05,the difference have not statistically significant.Conclusions The innovation capacityof master students working in primary hospitals is seriously insufficient,and its influence factors are closely related to both personal and environmental factors.Targeted innovation knowledge training and appropriate incentive mechanism are effective measurements to improve their innovation capacity.The necessary condition of facilitiesis thepremise and guarantee for them to carry out the science and technology innovation.
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BACKGROUND:Accumulative evidence supports that co-culture technology can be applied to construct the tissue-engineered cartilage with excellent biological characters. OBJECTIVE:To elaborate the co-culture concept and conclude and analyze seed cell sources, cel mixed ratio, spatial y-defined co-culture models and biomaterials in co-culture systems to conclude and analyze the biological characters of tissue-engineered cartilage, and to prospect progression of co-culture systems in cartilage tissue engineering. METHODS:The first author retrieved the databases of PubMed, Web of Science, and CNKI for relative papers published from January 1976 to May 2016 using the keywords ofco-culture, co-culture systems;articular cartilage, chondrocytes, mesenchymal stem cells;tissue engineering, articular cartilage tissue engineeringin English and Chinese, respectively. Finally 60 literatures were included in result analysis, including 1 Chinese and 59 English articles. RESULTS AND CONCLUSION:Co-culture technology emphasizes the role of microenvironment in terms of various physical, chemical and biological factors in the cell processing. In cartilage tissue engineering, co-culture systems contribute to maintain the viability and natural cell phenotype of chondrocytes and induce cartilage differentiation of mesenchymal stem cells. In addition, co-culture technology provides a novel way for cartilage tissue engineering to overcome the shortage of chondrocytes and repair injury to the cartilage-subchondral bone. However, the mechanisms of cell-cell interaction in co-culture systems still need to be explored in depth, so as to optimize the co-culturing conditions and construct perfect tissue-engineered cartilage.
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Objective Current study was aimed to investigate the barrier of research conduction in primary hospital, andTo take appropriate countermeasures to improve the research ability in primary hospital.Methods Convenience sampling method was adopted, and 302 physicians were selected and interviewed using a designed questionnaire.Results 89.41％ of the participants believed that it is not appropriate to conduct research in primary hospitals because the hospital could not provide appropriate condition for research activity.There were lacks of research consciousness, research atmosphere, and research capacity in primary hospital.Conclusions These medical staff in primary hospital appeared a negative attitude to research, while negative attitude exhibited positive correlation with the level of hospital, academic atmosphere, and research capacity.To improve research capacity in primary hospital, it is important to establish continuing education program to train the physicians for research ability, and to change the research environment in the primary hospitals.In addition, the incentive system may be able to encourage physicians to actively conduct research.
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BACKGROUND:At present, a variety of extracel ular matrix-derived scaffolds have been successful y applied for cartilage tissue engineering in experiment and clinical practice. OBJECTIVE:To summarize the application and research status of extracel ular matrix-derived scaffolds in cartilage tissue engineering. METHODS:A computer-based online search in PubMed, CNKI, CqVip and WanFang databases was performed using the keywords of“tissue engineering, cartilage, extracel ular matrix, scaffolds”in English and Chinese, respectively. A total of 1 140 literatures were retrieved, and final y 65 eligible literatures were included. RESULTS AND CONCLUSION:In terms of the components, extracel ular matrix-derived scaffolds are divided into monomeric natural polymers, mixed natural polymers, natural polymers compositing with synthetic polymers as wel as acel ular extracel ular matrix-derived materials. Extracel ular matrix-derived scaffolds hold good biocompatibility and degradability, and can promote proliferation and differentiation of choncrodytes;therefore, they as good bionic scaffolds have been applied for cartilage tissue engineering in clinical practice, However, poor mechanical properties and difficulty to molding should never be ignored. Further research should focus on improving the preparation technology by combining synthetic materials with extracel ular matrix-derived scaffolds for cartilage tissue engineering.
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Objective To investigate the identity of the scientific research in different grade hospital medical staff in different levels and analysis of the influence factors and improvement strategy.Methods A total of 453 in different grade hospital medical staff in different levels from some district in China were recruited.Results Hospital of different levels, different titles and different degree and professional medical staff have significant differences to the identity of the scientific research, P＜0.001. Its influence factors including consciousness, ability, interest, atmosphere, time, energy, and so on have significant differences, P＜0.001. Conclusions different grade hospital medical staff in different levels have significant differences to the identity of the scientific research, the higher the level, the higher the identity, but have different influence factors.The level of different grade hospital scientific research should be improved according to different influence factors make corresponding strategies.
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Objective To investigate the effects and mechanisms of electroacupuncture at Tinggong and Yifeng on the local expression of insulin like growth factor-1 (IGF-1) and glucose metabolism in the auditory cor‐tex of guinea pig .Methods Eighteen Adult pigmented guinea pigs were randomly divided into 3 groups .Guinea pigs in electroacupuncture at auricular points group (EAPG ,n= 7) were electroacupunctured at Tinggong and Yifeng acupoints simultaneously for 15 minutes every day ,and electroacupunctur lasted 7 days .The electroacupuncture at non acupoint group (ENAG ,n=6) was electroacupunctured at non acupoints for the same time .The control group (CG ,n=5) received no treatment .After anesthetized ,guinea pigs were injected 18 F-FDG via dorsocuboidal vein , and scanned by PET/CT .PET image and CT image were processed and reconstructed in the workstation to observe the uptake of imaging agent in the brain of guinea pigs .The maximum SUV values and its ratios between auditory cortex and cerebellum were measured .The expression of IGF-1 mRNA were detected by real-time fluorescence quantitative PCR .The results were analyzed by the one-way ANOVA and P<0 .05 means statistical significance . Results 1 .Changes in glucose energy metabolism in the auditory cortex .The ratios of the maximum SUV value betweenthe auditory cortex and cerebellum were 0 .75 ± 0 .06 ,0 .84 ± 0 .05 and 0 .71 ± 0 .06 for CG ,EAPG and ENAG re‐spectively .There was a significant difference between the CG and EAPG (P=0 .042) ,the EAPG and ENAG (P=0 .009) ,and no significant difference between the CG and ENAG (P=0 .361) .2 .The fold changes in IGF-1 mR‐NA were 1 .34 ± 0 .24 ,2 .03 ± 0 .36 and 0 .92 ± 0 .23 for CG ,EAPG and ENAG respectively .There was a significant increase in IGF-1 mRNA expression in auditory cortex of the EAPG (P=0 .002 ,compared with the CG) ,and a significant difference between the EAPG and ENAG groups (P<0 .001) .Conclusion 1 .Acupuncturing at Tinggong and Yifeng point can improve glucose metabolism in the auditory cortex of guinea pig . 2 . Acupuncturing at Tinggong and Yifeng point can result in increase of the local expression of IGF-1 in the auditory cortex of guinea pig .
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BACKGROUND:Cartilage extracelular matrix with a large number of signaling molecule proteins and factors is likely to be an ideal material for tissue engineering cartilage. OBJECTIVE: To investigate the possibility of calcium alginate and cartilage extracelular matrix combined with microencapsulated stem cels derived from human umbilical cord Wharton’s jely to construct ectopic tissue-engineered cartilage in nude mice. METHODS: Microfilament suspension of the cartilage extracelular matrix was prepared. Human stem cels derived from Wharton’s jely of the umbilical cord were inoculated in to calcium alginate and cartilage extracelular matrix gel microspheres as experimental group. Stem cels derived from human umbilical cord Wharton’s jely were incubated in simple alginate gel microspheres as control group. After in vitro culture, the microspheres wereimplanted into the dorsal subcutaneous tissue of nude mice. Samples were taken after 4 weeks, respectively, for gross and histological observation. RESULTS AND CONCLUSION:The stem cels exhibited paralel-chondrocyte morphology in microspheres, which grew and proliferated quite wel during in vitro culture. A new paralel-cartilaginous tissue was found in the subcutaneous tissue 4 weeks after surgery in the experimental group, and the tissue was positive for hematoxylin-eosin, safranine O, toluidine blue and colagen II. A large number of paralel-chondrocytes and cartilage lacuna-like structures were observed under a microscope with no obvious inflammatory reaction around the microspheres. The control group showed the partial degradation of microspheres, surrounded by only a smal number of inflammatory cels and lymphocytes. Calcium alginate and cartilage extracelular matrix microspheres have a rather good histocompatibility which can be used to construct paralel-cartilaginous tissues by implanting stem cel-microspheric compound into the subcutaneous tissue of nude mice.
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Objective To investigate the scientific research ability and training needs of the new posts of medical undergraduates for better training them.Methods A total of 62 new posts of medical undergraduates from a level-two general hospital in China were recruited by questionnaire survey.Resuits the scientific research ability of the new posts of medical undergraduates is poor,so it is very necessary for their in-service training,93.5~ of them have interest in scientific research and hope to get the training,especially want to take part in the practical activity.Conclusions It is not better that the scientific research ability of the new posts of medical undergraduates,so as early as possible to give the scientific research skill training to them.
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Objective To evaluate the relationship between the level of AMP-activated protein kinase (AMPK) in hippocampus and cognitive dysfunction after splenectomy in aged rats.Methods Sixty-three male aged Sprague-Dawley rats,weighing 480-550 g,were randomly divided into 3 groups (n =21 each):control group (group C),anesthesia group (group A),and surgery group (group S).Morris water maze (MWM) test was performed to evaluate the spatial learning and memory ability before surgery and at 1,3 and 7 days after surgery.The escape latency and swimming distance were recorded.Seven rats were chosen after MWM test was performed at 1,3 and 7 days after surgery and sacrificed.Their hippocampi were removed for detection of the expression of AMPK and phosphorylated (p-AMPK) (by Western blot).Results Compared with the baseline,the escape latency and swimming distance were significantly prolonged at 1 and 3 days after surgery in group S (P ＜ 0.05).Compared with group C,the escape latency and swimming distance were significantly prolonged at 1 and 3 days after surgery,the expression of AMPK was up-regulated at 1,3 and 7 days after surgery,and the expression of p-AMPK was up-regulated at 1 and 3 days after surgery in group S (P ＜ 0.05),and no significant changes were found in the indices mentioned above in group A (P ＞ 0.05).Conclusion Increased AMPK level in hippocampus is the regulatory mechanism of the body adapting to the development of cognitive dysfunction after splenectomy in aged rats.
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To investigate the current situation of research management in basic hospital,sum up the experience and effects,study the efficient method to improve the level of research management.
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ObjectiveTo study the influence of humanized management mode for infection consciousness and control effect of infection of medical staff. Methods90 medical staff from June 2010 to March 2011 were selected as research object,and they were randomly divided into the control group and the observation group with 45 cases in each group,then the infection consciousness,grasping situation of related knowledge and infection control effect of two groups before and after the management on the third and sixth month were analyzed and compared.Results The infection consciousness,grasping situation of related knowledge and infection control effect of the observation group after the management on the third and sixth month were all better than those of the control group,there were significant differences. ConclusionsThe humanized management mode plays an active role in improving infection related evaluation indices of hospital staff,and is also effective in control of infection.
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Objective To probe the immunological traits of mesenchymal stem cells derived from umbilical cord Wharton's jelly (WJMSCs). Methods The diced Wharton's jelly which was from healthy fullterm birth human umbilical cord was cultured. The mesenchymal stem cells were identified with mesenchymal stem cells markers expression by flow cytometry and multiple differentiation ability. The expression of MHC- Ⅰ / Ⅱ, costimulatory molecules (CD40, CD80 and CD86) was detected with flow cytomctry, immunocytochemistry, and RT-PCR. The expression of immune inhibitors like HLA-G, IDO, and PGE2 was detected by immunocytochemistry and RT-PCR. The expression of immune-related molecules as IL-10, TGF-β, FGF and VEGF was detected with antibody microarray and western blot. Further more, to clarify the in vivo immune reaction of hWJMSCs, we fabricated the hWJMSC-scaffold constructs and implanted them into the rabbit backs. The lymphocyte infiltration and implanted cell survival observed with immunofluorescence. Results After culturinge of diced Wharton's jelly tissue, we obtained spindle-shaped cells. With differentiation medium, the cells can differentiate into osteoblasts, chongdrocytes, adipose cells and schwann cells. Expression of MHC, costimulatory molecules, and a series of immune suppressive-related molecules was found. Immune inhibitors as HLA-G, 1DO, PGE2, and immune suppressive related molecules as HGF, VEGF, TGFand IL-10 were positively expressed. But the cells did not express MHC-Ⅱ. No immune rejection was observed in vivo after implantation of hWJMSC-scaffold constructs. Conclusion It can be concluded that hWJMSCs have very low immunogenicity, which means the cells have potential to induce immune tolerance.The hWJMSCs do not provoke immune rejection in vivo.
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Objective To observe the effects of fasudil hydrochloride injections on the levels of endothdin(ET)-1,nitric oxide(NO)in plasma and cerebrospinal fluid(CSF)in patients with subarachnoid hemorrhage(SAH),and analyze,its mechanisms in preventing cerebral vasospasm(CVS).Method Sixty SAH cases were randomly divided into fasudil group(30 cases)and control group(30 cases).On 2nd and 10th day after in hospital,the speed of cerebral blood flow was measured by transeranial Doppier(TCD),and the levels of ET-1,NO in plasma and CSF were measured by radio-immunity.Results The incidence of CVS in fasudil group were significantly less than those in control group[6.67%(2/30)vs 36.67%(11/30),P<0.05].On the 10th day,the levels of ET-1 in plasma and CSF in fasudil group were signitlcandy lower than those in control group[(118.23±14.56)ng/L vs(132.26±15.18)ng/L,(138.23±16.58)ng/L vs (156.24±17.54)ng/L ](P<0.05),the levels of NO were significantly higher than those in control group [(88.25±15.54)μmol/L vs(70.26±14.86)μmol/L,(104.27±16.52)μmol/L vs(92.43 ±12.51)±mol/L](P<0.05).But there were no significant difference on the 2nd day(P>0.05).Conclusion Fasudil can reduce CVS in patients with SAH by lowering the levels of ET-1 and increasing the levels of NO in plasma and CSF.
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Objective To investigate and analysis the actuality and demands of scientific researchers in state clinical research facility of TCM, in order to provide evidences for policy making. Methods All the trainees taken part in the meeting for the training of clinical research method were assigned to answer the self-designed questionnaire. Results Of all these people, 47.58 percent people had senior professional title, 84.14 percent people had doctorate or master degree, 57.24 percent people had participated in project research at provincial or ministerial level as key personnel, 35.17 percent people had participated in a key disease research as directors, 65.52 percent people had taken methodology training of clinical research,30.34% of who trained by evidence-based medicine. The majority of these people had clear understanding in methodology of clinical research, who believed that evidence-based medicine and system evaluation are the most difficult subjects to understand and practice, hoping to learn more about the knowledge on statistics. Conclusion Clinical researchers of state clinical research facility of TCM had sound basis for scientific research, but relatively lacking of key disease research and systematic knowledge of scientific methodology, which needed to be enhanced.
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To analyze the expression of bile acid transport correlative proteins in the placenta of patients with intrahepatic cholestasis of pregnancy [ICP]. This case-control study was performed in the Department of Gynecology and Obstetrics, West China Second University Hospital, Sichuan University, Chengdu, Sichuan, China from March 2007 to October 2008. Real time reverse transcriptase polymerase chain reaction was applied for the mRNA expression measurement of 8 bile acid transport correlative proteins, organic anion transporting polypeptide [OATP]1A2, OATP1B1, multidrug resistance protein [MRP]1, MRP2, anion exchanger [AE]2, bile salt export pump [BSEP], multidrug resistance 3, and familial intrahepatic cholestasis [FIC]1, in normal human placentas [n=20] and those with ICP [n=20]. All the transcripts except OATP1B1 and BSEP were detected. Both OATP1A2 and AE2 mRNA were higher while FIC1 was lower in ICP patients. The alteration of bile acid transport correlative proteins OATP1A2, AE2, and FIC1 may be involved in the fetal cholestasis of ICP