Intraocular pressure distribution and reference interval of high-altitude eye health screening population from Xining, Qinghai / 中华实验眼科杂志

Objective:To investigate the distribution of intraocular pressure (IOP) in high-altitude population aged 18 years and over in Xining, Qinghai and establish the reference interval (RI) of IOP.Methods:A cross-sectional study was conducted in Xining, Qinghai Province at 2.271 km above sea level from September 2019 to May 2020.Ophthalmic examinations and IOP measurement were conducted among subjects from Physical Examination Center of Qinghai Provincial People's Hospital.The subjects who had been living in Xining without leaving for three months were enrolled.Ophthalmic examinations included vision examination, IOP measurement, slit-lamp microscopy, fundus photography, anterior and posterior segment optical coherence tomography.IOP was measured using Goldmann applanation tonometry under local anesthesia.Subjects with factors that could cause significant changes in IOP and affect the accuracy of IOP measurement, and those who were unable to receive IOP measurement were excluded.Subjects were grouped according to sex, age and ethnicity, and the distribution and RI of IOP were compared among all groups.This study adhered to the Declaration of Helsinki.The study protocol was approved by the Ethics Committee of Beijing Tongren Hospital, Capital Medical University (No.TRECKY2017-024). Written informed consent was obtained from each subject.Results:A total of 6 120 subjects (6 120 eyes) aged 18-90 years old were enrolled, including 2 850 males and 3 270 females with average age of (45.54±13.85) years.The average IOP of high-altitude population in Xining, Qinghai Province was (14.32±1.93) mmHg (1 mmHg=0.133 kPa), with the RI of 10.54-18.10 mmHg.The average IOP was (14.42±1.98) mmHg in male with the RI of 10.54-18.30 mmHg, (14.23±1.88) mmHg in female with the RI of 10.55-17.91 mmHg.The IOP of male was higher than that of female ( t=3.71, P<0.001). The IOP of Han, Tibetan, Hui and other nationalities were (14.38±1.91), (13.93±2.06), (14.21±1.87), (13.94±1.95) mmHg, respectively, with a statistically significant overall difference ( F=6.73, P<0.001). The IOP of Han nationality was significantly higher than that of Tibetan, Hui and other nationalities, and the differences were statistically significant (all at P<0.05). Conclusions:RI of IOP in high-altitude population from Xining, Qinghai is lower compared with normal altitude area.

Research progress on the relationship between liver cirrhosis and thyroid hormones / 中华肝脏病杂志

There exists a complex relationship between liver and thyroid hormones. Liver plays an important role in the activation, inactivation, transportation, and metabolism of thyroid hormones. At the same time, thyroid hormones also affect hepatocytes activity and liver metabolism, such as lipid and bilirubin metabolism. Importantly, thyroid hormone levels often change abnormally in patients with liver cirrhosis. Therefore, studying the change of thyroid hormone levels in patients with liver cirrhosis has a certain clinical value for assessing the severity, prognosis, diagnosis and treatment. This paper reviews the research progress on the relationship between liver cirrhosis and thyroid hormone.

Molecular Mechanism of Aurora Kinase A Regulating the Meiosis of Oocyte / 中国医学科学院学报

Aurora kinase A (AURKA),a family member of aurora kinases,is involved in mitotic entry,maturation and separation of centrosome,assembly and stabilization of bipolar spindle,and condensation and separation of chromosome.Studies have demonstrated that AURKA plays a similar role in meiosis,while the specific mechanism and the similarities and differences in its role between meiosis and mitosis remain unclear.Therefore,we reviewed the studies about the localization and activation of AURKA in oocyte meiosis,and compared the role of AURKA in regulating spindle formation,activating spindle assembly checkpoint,and correcting the kinetochore-microtubule attachment between the meiosis of oocytes and the mitosis of somatic cells.This review will lay a theoretical foundation for revealing the mechanism of AURKA in the regulation of cell division and for the clinical research related to cancer and reproduction.

Study on the mechanical differences between single-row belt rivets and double-row suture bridge in repairing rotator cuff injury / 中国骨伤

OBJECTIVE@#To compare and analyze the mechanical differences between single-row suture anchor fixation for repairing rotator cuff injuries and double-row suture bridges for repairing rotator cuff injuries from a biomechanical perspective.@*METHODS@#The CT scan data of healthy adult shoulder joint were imported into Mimics, Geomagics and Hypermesh to carry out reverse reconstruction of two repair models, material assignment and mesh division, and the tearing of supraspinatus muscle was designed. After treatments, the load and boundary conditions were applied to the shoulder joint in ABAQUS software. The shoulder joint was fixed with four working conditions including flexion 15 °, flexion 30 °, internal rotation 15 ° and internal rotation 30 ° after anchor fixationand repair. The stress changes of the upper rotator cuff muscle and the anchor with thread were compared under these four conditions.@*RESULTS@#Under the two flexion conditions, the stress of the supraspinatus in the double row suture bridge fixation model was 8.3% and 12% less than that in the single-row suture anchor fixation, respectively. Under the two internal rotation conditions, the stress of supraspinatus in the double row suture bridge fixation model was 47% and 48% less than that in the single row fixation repair model, respectively.@*CONCLUSION@#The "load sharing" effect between the two rows of four anchors makes the stress distribution more dispersed, increases the contact area between the supraspinatus muscle and the humerus, reduces the stress of the anchor, avoids the serious stress concentration phenomenon, and explains the advantages of the fixation method of the double row suture bridge from the biomechanical angle.

CT and Magnetic Resonance Imaging Findings of the Intracranial Extra-cerebral Chondroma:A Case Report / 中国医学科学院学报

Intracranial intradural chondroma is a rare disorder,the imaging findings of which have been rarely reported.The current study reported a case of intracranial extra-cerebral chondroma and described the detailed CT and magnetic resonance imaging findings,which would provide valuable imaging evidence for the diagnosis of intracranial extra-cerebral chondroma.

Study on lignans compounds from Lavandula angustifolia / 中草药

Objective: To investigate the lignans compounds constituents of Lavandula angustifolia. Methods: The chemical constituents were isolated and purified by TLC, silica gel, MCI-gel, and RP-HPLC, and their structures were identified by analysis of spectroscopic evidences and physicochemical properties. Results: A total of 11 constituents were isolated from L. angustifolia and elucidated as pinoresinol (1), syringaresinol (2), fraxiresinol-4'-O-β-D-glucopyranoside (3), syringaresinol-4'-O-β-D-glucopyranoside (4), 8-hydroxypinoresinol-4-O-β-D-glucopyranoside (5), rel-(2α,3β)-7-O-methylcedrusin (6), lariciresinol-4'-O-β-D-glucoside (7), (2S,3R)-2,3-dihydro-2-(4-hydroxy-3-methoxyphenyl)-3-hydroxymethyl-7-methoxybenzofuran-5-(trans) propen-1-ol-3-O-β-glucoside (8), (7S,8R)-dihydrodehydrodiconiferyl alcohol-9-β-D-glucopyranoside (9), (7R,8R)-7,8-dihydro-9'-hydroxyl-3'-methoxyl-8- hydroxymethyl-7-(4-hydroxy-3-methoxyphenyl)-1'-benzofuranpropanol-9'-O-β-D-glucopyranoside (10), and (E)-3-((2S,3S)-2-(4- hydroxy-3-methoxyphenyl)-3-hydroxymethyl-7-methoxy-2,3-dihydrobenzofuran-5-yl) allyl-2-hydroxyacetate (11). Conclusion: The 11 compounds are isolated from this plant for first time.

Dual mobility total hip arthroplasty for the treatment of femoral neck fracture with hemiplegia / 中国骨伤

OBJECTIVE@#To investigate the clinical effects of dual mobility total hip prosthesis in treating femoral neck fracture patients with hemiplegia.@*METHODS@#A retrospective analysis was performed on 18 patients with femoral neck fracture combined with hemiplegia who underwent dual mobility total hip prosthesis replacement from March 2014 to December 2016. The follow up data of these patients was complete. There were 5 males and 13 females, aged 65 to 70 years old with an average of (66.50±1.38) years. The left side was involved in 12 cases, while the right side in 6 cases. There were 4 cases with Garden Ⅲ type and 14 cases with type Ⅳ. Limb muscle strength of hemiplegia were in grade Ⅳ. The posterior-lateral approach of hip joint was used in surgery for all patients. The implant position, dislocation and loosening of the prosthesis were evaluated by X-ray examination. Harris hip score and the Merle D'aubigne score were used to assess the hip function in the follow up.@*RESULTS@#The operation duration was for 70-90 (81.56±7.48) min and the blood loss during the operation was for 160-200 (170.32± 12.56) ml. No blood was transfused during the operation. Postoperative incisions were healed at the first stage. The follow-up time was for 28-60(36.0±3.5) months. Harris hip score increased from 16.94±0.73 preoperatively to 96.19±1.27 at the final follow-up(<0.05). Merle D 'Aubigne score increased from 3.96±0.06 preoperatively to 16.81±0.63 at the final follow-up(< 0.05). No fracture or nerve or vascular injury were found during the operation. The postoperative X-ray showed that the prosthesis was in good position. No complications such as joint dislocation, dislocation of prosthesis, loosening of prosthesis, fracture around the prosthesis, pain in the front of thethigh, fracture of the self tapping screw in the ilium, and delayed infection occurred in the patients after operation.@*CONCLUSION@#Dual mobility total hip prosthesis has the advantages of both good initial stability and low dislocation rate of the prosthesis, and the clinical application of total hip replacement in hemiplegic femoral neck fracture is satisfactory.

Supratentorial Primary Central Nervous System Lymphoma with Hyperperfusion:Report of One Case / 中国医学科学院学报

We reported a case of supratentorial primary central nervous system lymphoma with hyperperfusion.Computed tomography revealed hyperdense lesions on the bilateral centrum semiovale with obvious edema.Magnetic resonance imaging demonstrated that the lesion presented slightly long and iso-T1 signal and slightly long and long T2 signals;hyperintensity was found on diffusion-weighted imaging,with relatively high apparent diffusion coefficient value compared with the adjacent normal white matter.Contrast-enhanced imaging revealed bilateral evenly enhanced lesions,along with patchy non-enhanced shadows in right-sided lesion.The perfusion-weighted imaging revealed hyperperfusion in bilateral lesions.

Clinical effectiveness of Subjective Global Nutritional Assessment in hospitalized children with cerebral palsy / 中国当代儿科杂志

OBJECTIVE@#To investigate the nutritional status of children with cerebral palsy (CP) and the clinical effectiveness of Subjective Global Nutritional Assessment (SGNA) in nutritional assessment of hospitalized children with CP.@*METHODS@#A total of 208 children with CP, aged 1-5 years, who were hospitalized from April to October 2019 were enrolled as subjects. SGNA was used to investigate nutritional status, and the Z-score method recommended by the World Health Organization was used as a reference standard to validate the clinical effectiveness of SGNA.@*RESULTS@#The detection rate of malnutrition in children with CP was 42.3% by SGNA and 39.4% by the Z-score method (P>0.05). The application of SGNA showed high consistency between different evaluators (κ=0.621, P<0.001). With the Z-score method as the reference standard, SGNA had a sensitivity of 80.5%, a specificity of 82.5%, a positive predictive value of 75.0%, and a negative predictive value of 86.7%, and high consistency was observed between the two evaluation methods (κ=0.622, P<0.001). SGNA was moderately consistent with weight-for-age Z-score and height-for-age Z-score (κ=0.495 and 0.478 respectively, P<0.001) and was poorly consistent with weight-for-height Z-score (κ=0.197, P<0.05).@*CONCLUSIONS@#There is a relatively high incidence rate of malnutrition in children with CP. SGNA can be used as a tool to assess the nutritional status of children with CP.

Correlation Analysis of " Toxin Damaging Brain Collaterals" from Glymphatic System / 中国实验方剂学杂志

The collaterals are branches of the meridians and vessels system, and have the roles of connecting upper-lower and interior-exterior portions of the body, the characteristics of two-way flow in supporting the operation of Qi and blood, and the functions of material exchange and metabolism. The brain is the intersection of the Yang meridians. Crisscross brain collaterals permeate Qi and blood to enrich the brain, and spread Yang Qi, in order to warm the brain-mind, and provide material basis and source power to the " brain governing mind" . Under pathological conditions, cerebral collaterals are blocked, and toxic pathogens are endogenous, resulting in " toxin damaging brain collaterals" . This theory is not only applied to the study of stroke pathogenesis, but also extended to other encephalopathy, such as dementia, which promoted the development of the theory of pathogenesis in traditional Chinese medicine. Recently, a " glymphatic system" was discovered in the brain, which is an exchange flow system of cerebrospinal fluid-brain interstitial fluid mediated by astrocyte. The glymphatic system transports nutrients and neuroactive substances, such as glucose, lipids, electrolytes and apolipoprotein E in the cerebrospinal fluid, to brain tissue, and also removes metabolic products (such as lactic acid), soluble proteins (such as β-amyloid protein and Tau protein) from the brain and foreign bodies, which are important liquid flow systems that maintain the homeostasis of the brain. The discovery of the glymphatic system provides a new perspective for the study of pathological mechanism of neurological diseases, and may become a new target for interventions in neurological diseases, such as cerebrovascular diseases and neurodegenerative diseases. As a widely distributed cerebral metabolic waste removal way and material delivery system, the lymphatic system may be the biological foundation of " brain collateral" disease, and a cross point of understanding on " toxin impairing brain collaterals" by Western and traditional Chinese medicine. The study based on the glymphatic system will give a more rational explanation on " toxic damage to brain collaterals" .

Fumigaclavine C attenuates adipogenesis in 3T3-L1 adipocytes and ameliorates lipid accumulation in high-fat diet-induced obese mice

Fumigaclavine C (FC), an active indole alkaloid, is obtained from endophytic Aspergillus terreus (strain No. FC118) by the root of Rhizophora stylosa (Rhizophoraceae). This study is designed to evaluate whether FC has anti-adipogenic effects in 3T3-L1 adipocytes and whether it ameliorates lipid accumulation in high-fat diet (HFD)-induced obese mice. FC notably increased the levels of glycerol in the culture supernatants and markedly reduced lipid accumulation in 3T3-L1 adipocytes. FC differentially inhibited the expressions of adipogenesis-related genes, including the peroxisome proliferator-activated receptor proteins, CCAAT/enhancer-binding proteins, and sterol regulatory element-binding proteins. FC markedly reduced the expressions of lipid synthesis-related genes, such as the fatty acid binding protein, lipoprotein lipase, and fatty acid synthase. Furthermore, FC significantly increased the expressions of lipolysis-related genes, such as the hormone-sensitive lipase, Aquaporin-7, and adipose triglyceride lipase. In HFD-induced obese mice, intraperitoneal injections of FC decreased both the body weight and visceral adipose tissue weight. FC administration significantly reduced lipid accumulation. Moreover, FC could dose-dependently and differentially regulate the expressions of lipid metabolism-related transcription factors. All these data indicated that FC exhibited anti-obesity effects through modulating adipogenesis and lipolysis.

Multicystic Encephalomalacia:Report of One Case / 中国医学科学院学报

The magnetic resonance imaging findings of multicystic encephalomalacia are featured by bilateral frontal large cystic lesion with corpus callosum involvement,evident heterogeneous enhancement of the lesion margin,ring hyperintensity on diffusion weighted imaging,and high choline peak and low N-acetylaspartate peak of the enhanced lesion margin on magnetic resonance spectroscopy.This article reports a case of multicystic encephalomalacia.

Ependymoma in Sellar Region:Report of One Case / 中国医学科学院学报

Ependymoma arises from the ependymal cells of the ventricles and the ependymal cell nest in the white matter of the extra-ventricles. It may be located inside or outside ventricle and can be anatomically classified into supra- and infratentorial ependymomas. Supratentorial ependymoma can be found both inside and outside ventricle but is rarely seen in the sellar regio. This article reports a pathologically confirmed ependymoma case featured by plastic growth,nodular calcification,and flow-void signal.

Effect of SUMO Modification on the Chromosomal Aneuploidy in Oocytes / 中国医学科学院学报

The chromosomal aneuploidy in oocytes is one of main causes of abortion and neonatal birth defects.It is mainly due to the premature separation of sister chromatid caused by the loss of Cohesin protein complex and the non-disjunction sister chromatids caused by abnormal microtubule dynamics aneuploidy.As a pathway of protein post-translational modification,SUMO modification(or SUMOylation)involves many physiological regulation processes including cell proliferation,differentiation,apoptosis,and cycle regulation.In the oocytes,SUMOylation can regulate the localization of Cohesin protein complex on the chromosome to affect the chromosomal aneuploidy in oocytes caused by premature separation of sister chromatid.On the other hand,SUMOylation can regulate the microtubule dynamics to affect the chromosomal aneuploidy in oocytes caused by non-disjunction sister chromatids.Therefore,SUMOylation plays an important role in regulating the chromosomal aneuploidy of oocytes;the exact mechanisms via which the SUMOylated substrates affect aneuploidy in oocytes remain unclear.This articles reviews the roles of SUMOylation in premature separation and non-isolated chromatid aneuploidy in oocyte from the effects of SUMOylationon Cohesin protein complex and microtubule dynamics.

Magnetic Resonance Imaging Features of the Supratentorial Extra-axial Hemangioblastoma:A Case Report / 中国医学科学院学报

We reported a case of supratentorial extra-axial hemangioblastoma diagnosed by magnetic resonance imaging (MRI). As a simple solid mass,this tumor has its unique MRI features due to its tissue structures.

Clinicopathologic features and prognosis of adenoid cystic carcinoma of external auditory meatus / 中华病理学杂志

Objective@#To investigate clinicopathologic features and prognosis of adenoid cystic carcinoma (ACC) involving external auditory meatus.@*Methods@#The clinical presentation and follow-up data of 63 patients with ACC of external auditory canal were collected from January 2006 to February 2017 at PLA General Hospital and Hainan Branch of PLA General Hospital. The clinicopathologic features and prognostic factors of external auditory canal ACC were analyzed.@*Results@#(1) There were 28 males and 35 females and the average age of the first diagnosis was 48.9 years (22-81 years). The tumors showed cribriform pattern in 35 cases (15 cases of late stage), tubular pattern in 14 cases (8 cases of late stage), and solid pattern in 14 cases (9 cases of late stage). Cases with solid pattern was relatively more frequent than that of cribriform pattern and tubular pattern, but the difference was not statistically significant (P>0.05). (2) The average follow-up time was 62.4 months (2-228 months) in the 57 available cases. Among the 33 cases with recurrence, 18 cases had local recurrence and 15 cases had distant metastasis. The mean recurrence time was 40.6 months (2-204 months). Nine patients died of ACC: 2 cases in early stage (died at 48 and 102 months after the first treatment), 7 cases in late stage and 57 with (died at 9, 30, 32, 60, 72, 94 and 228 months). (3) Among the 37 patients with perineural invasion, there were 21 cases of cribriform pattern, 4 cases of tubular pattern and 12 cases of solid pattern; the number of cases in early stage and late stage were 15 and 22, respectively; and the differences were statistically significant (P<0.05). In addition, 31 cases had otalgia among the 37 patients with perineural invasion, where differences were not significant (P>0.05). (4) Thirty of 45 cases with tumor resection or partial resection of temporal bone had recurrence, whereas 3 of 12 cases of tumor combined with superficial lobectomy of parotid gland had recurrence. The difference was statistically significant (P<0.05). Postoperative adjuvant radiotherapy was given in 19 cases, including 7 cases of early stage (2 cases of recurrence), and 12 cases of late stage (8 cases of recurrence), among which there was no significant difference (P>0.05).@*Conclusions@#ACC occurring in external auditory canal frequently recurs. Superficial parotid lobectomy at the first operation is necessary to prevent tumor recurrence. Postoperative adjuvant radiotherapy has certain curative effect on patients with early stage tumor, but it does not affect the recurrence rate. Patients at late stage are more prone to perineural invasion than those in early stage. In addition, cribriform and solid patterns are more common that tubular pattern, and there is no significant correlation between perineural invasion and otalgia.

The progresses of molecular mechanism of Isoniazid resistance in Mycobacterium Tuberculosis / 医学研究生学报

Mycobacterium tuberculosis is the causative agent of tuberculosis, which is a threat to public health worldwide. Isoniazid is one of the most active compounds used to treat tuberculosis worldwide. The pro-drug isoniazid is activated by catalase-peroxidase (KatG), and the active isoniazid products are targeted to InhA. The molecular mechanisms of isoniazid resistance involve several genes mutations. Mutation in the katG gene is the major cause for isoniazid resistance, followed by inhA, kasA, oxyR . Efflux pump systems also play important role in conferring isoniazid resistance. Understanding the mechanisms operating behind isoniazid action and resistance would enable better diagnosis and treatment of isoniazid-resistant tuberculosis.

Role of microRNA-126-5p in myocardial injury induced by doxorubicin / 中国病理生理杂志

AIM:To observe the expression of microRNA-126-5p during myocardial injury and its role in myo-cardial cell injury induced by adriamycin(also called doxorubicin, DOX).METHODS: The BALB/c mouse model of DOX-induced acute and chronic myocardial injury was established via intraperitoneal injection of DOX.HE staining was applied to observe the morphological changes of myocardial tissues.Lactate dehydrogenase(LDH)in serum was detected and PowerLab system was used to detect the influence of DOX on the changes of ±dp/dtmax.The expression of microRNA-126-5p in injured myocardial tissues and the H 9c2 cells exposed to DOX was detected by real-time PCR.Gain-and loss-of-function experiments were conducted to detect the role of microRNA-126-5p in H9c2 cells treated with DOX on LDH release and caspase-3 activation.RESULTS:In acute and chronic DOX myocardial damage models in mice,HE staining showed disarranged myocardial fibers, dissolved myofibril and inflammatory cell infiltration.Higher serum LDH level and lower ±dp/dtmaxin DOX-treated mice than those in normal mice were found.Compared with the normal mice, the expression level of microRNA-126-5p was significant increased in the myocardium with DOX-induced injury.Similarly,the expression level of microRNA-126-5p was significant increased in the H9c2 cells treated with DOX.In addition, over-expression of microRNA-126-5p decreased cell viability and promoted apoptosis,while microRNA-126-5p ablation promoted the viability and inhibited the apoptosis of H9c2 cells.CONCLUSION:The microRNA-126-5p expression is up-regulated in myocar-dial injury induced by DOX,and microRNA-126-5p inhibits cell viability and promotes apoptosis induced by DOX.

Effect of poly(hydroxybutyrate-co-hydroxyoctanoate)/collagen composite osteochondral scaffold combined with bone marrow mesenchymal stem cells in the repair of articular osteochondral defects / 中国组织工程研究

BACKGROUND: Preliminary experiments have confirmed that poly(hydroxybutyrate-co-hydroxyoctanoate) (PHBHOx)/collagen composite osteochondral scaffold exhibits desirable pore structure and biocompatibility. OBJECTIVE: To investigate the effect of PHBHOx/collagen composite osteochondral scaffold carrying bone marrow mesenchymal stem cells in the repair of articular osteochondral defects in the weight-bearing area of rabbits. METHODS: Cone-shaped osteochondral defects were created in the femoral medial condyle of the right knee of 30 New Zealand white rabbits. Then, the rabbit models were randomized into three groups and underwent implantation of PHBHOx/collagen composite osteochondral scaffold carrying bone marrow mesenchymal stem cells in the scaffold-cell group, PHBHOx/collagen composite osteochondral scaffold in the scaffold group and no intervention in the control group. At 4 and 12 weeks after surgery, animals were sacrificed for gross, Micro-CT, histological and immunohistochemical collagen II observations. RESULTS AND CONCLUSION: At 12 weeks after surgery, Micro-CT scanning results suggested that osteochondral defects were not repaired in the control group, repaired incompletely in the scaffold group with many new bone trabeculae, and repaired completely in the scaffold-cell group. Histological results showed that at 4 weeks after surgery, the defects in the control group were filled with amorphous tissues, subchondral bone formation just occurred in the scaffold group but increased in the scaffold-cell group. At 12 weeks after surgery, trabecular bone structure with no cartilage lacuna was observed in the control group; incomplete subchondral bone formation was observed in the scaffold group, and the cartilage layer was repaired by the fibrous tissues; in the scaffold-cell group, osteochondral defect repair was complete, with the emergence of tidal line, and the newborn cartilage was completely integrated with the surrounding normal tissue in addition to a similar thickness. At 12 weeks after surgery, collagen II basically did not express in the control group, weakly expressed in the scaffold group and highly expressed in the scaffold-cell group. In short, the PHBHOx/collagen composite osteochondral scaffold promotes the repair of articular osteochondral defects in the weight-bearing area.

Expression and clinical significance of MMR protein and MLH1 promoter methylation testing in endometrial cancer / 中华妇产科杂志

Objective To explore the expression and clinical significance of mismatch repair (MMR)protein and MLH1 promoter methylation testing in endometrial cancer(EC). Methods A total of 420 cases with EC diagnosed by the surgical pathology examination from the Department of Pathology of PLA General Hospital, MLH1,MSH2,MSH6 and PMS2 protein in EC were detected by immunohistochemistry and methylation-specific multiplex ligation-dependent probe amplification(MS-MLPA) testing. Results (1)Of the 420 tumor cases, the total expression loss rate of MMR protein was 34.5%(145/420), the expression loss rates of MLH1,MSH2,MSH6 and PMS2 protein were respectively 17.1%(72/420), 8.1% (34/420), 7.4%(31/420), 26.2%(110/420)and loss rates of MLH1 and PMS2,MSH2 and MSH6 were 16.7%(70/420), 6.2%(26/420). When there was a loss of MMR protein expression, any one or more protein expression deletions in MLH1, PMS2, MSH2 and MSH6, it could be Lynch syndrome related endometrial carcinoma(LS-EC). The expression loss rate of MMR protein in the poorly differentiated endometrioid adenocarcinoma was higher than that in the well differentiated endometrioid adenocarcinoma(P<0.05).(2) The expression loss rate of MMR and PMS2 protein had statistically significant between the endometrioid adenocarcinoma and non-endometrioid adenocarcinoma(P<0.01). The expression loss rate of MSH2 protein had statistically significant in the stage Ⅲ(P<0.01). Moreover, there were also significant differences in depth of myometrial invasion and lymph node metastasis between the expression loss rate of MMR protein (P<0.05).(3)The expression loss rate of MLH1 protein was 72 cases and 57 cases had MLH1 promoter methylation testing(excluding those who were not qualified for DNA testing). The positive rate was 47.4% (27/57). Therefore, these patients were sporadic endometrial cancer, not non-LS-EC. Conclusions MMR protein may be play an important role in the development of endometrial cancer and be indicated poor prognosis. Immunohistochemical staining and MLH1 promoter methylation detection may be play an important role in the screening of the LS-EC.