Objective: To analyze the prevalence and the risk factors of fungal sepsis in 25 neonatal intensive care units (NICU) among preterm infants in China, and to provide a basis for preventive strategies of fungal sepsis. Methods: This was a second-analysis of the data from the "reduction of infection in neonatal intensive care units using the evidence-based practice for improving quality" study. The current status of fungal sepsis of the 24 731 preterm infants with the gestational age of <34⁺⁰ weeks, who were admitted to 25 participating NICU within 7 days of birth between May 2015 and April 2018 were retrospectively analyzed. These preterm infants were divided into the fungal sepsis group and the without fungal sepsis group according to whether they developed fungal sepsis to analyze the incidences and the microbiology of fungal sepsis. Chi-square test was used to compare the incidences of fungal sepsis in preterm infants with different gestational ages and birth weights and in different NICU. Multivariate Logistic regression analysis was used to study the outcomes of preterm infants with fungal sepsis, which were further compared with those of preterm infants without fungal sepsis. The 144 preterm infants in the fungal sepsis group were matched with 288 preterm infants in the non-fungal sepsis group by propensity score-matched method. Univariate and multivariate Logistic regression analysis were used to analyze the risk factors of fungal sepsis. Results: In all, 166 (0.7%) of the 24 731 preterm infants developed fungal sepsis, with the gestational age of (29.7±2.0) weeks and the birth weight of (1 300±293) g. The incidence of fungal sepsis increased with decreasing gestational age and birth weight (both P<0.001). The preterm infants with gestational age of <32 weeks accounted for 87.3% (145/166). The incidence of fungal sepsis was 1.0% (117/11 438) in very preterm infants and 2.0% (28/1 401) in extremely preterm infants, and was 1.3% (103/8 060) in very low birth weight infants and 1.7% (21/1 211) in extremely low birth weight infants, respectively. There was no fungal sepsis in 3 NICU, and the incidences in the other 22 NICU ranged from 0.7% (10/1 397) to 2.9% (21/724), with significant statistical difference (P<0.001). The pathogens were mainly Candida (150/166, 90.4%), including 59 cases of Candida albicans and 91 cases of non-Candida albicans, of which Candida parapsilosis was the most common (41 cases). Fungal sepsis was independently associated with increased risk of moderate to severe bronchopulmonary dysplasia (BPD) (adjusted OR 1.52, 95%CI 1.04-2.22, P=0.030) and severe retinopathy of prematurity (ROP) (adjusted OR 2.55, 95%CI 1.12-5.80, P=0.025). Previous broad spectrum antibiotics exposure (adjusted OR=2.50, 95%CI 1.50-4.17, P<0.001), prolonged use of central line (adjusted OR=1.05, 95%CI 1.03-1.08, P<0.001) and previous total parenteral nutrition (TPN) duration (adjusted OR=1.04, 95%CI 1.02-1.06, P<0.001) were all independently associated with increasing risk of fungal sepsis. Conclusions: Candida albicans and Candida parapsilosis are the main pathogens of fungal sepsis among preterm infants in Chinese NICU. Preterm infants with fungal sepsis are at increased risk of moderate to severe BPD and severe ROP. Previous broad spectrum antibiotics exposure, prolonged use of central line and prolonged duration of TPN will increase the risk of fungal sepsis. Ongoing initiatives are needed to reduce fungal sepsis based on these risk factors.
Infant ; Infant, Newborn ; Humans ; Birth Weight ; Intensive Care Units, Neonatal ; Retrospective Studies ; Tertiary Care Centers ; Infant, Extremely Low Birth Weight ; Gestational Age ; Infant, Extremely Premature ; Sepsis/epidemiology* ; Retinopathy of Prematurity/epidemiology* ; Bronchopulmonary Dysplasia/epidemiology*

Objective: To investigate the feasibility of Cai tube-assisted natural orifice specimen extraction surgery (NOSES) in gastrointestinal surgery. Methods: This was a descriptive case-series study. Inclusion criteria: (1) colorectal or gastric cancer diagnosed by preoperative pathological examination or redundant sigmoid or transverse colon detected by barium enema; (2) indications for laparoscopic surgery; (3) body mass index <30 kg/m² (transanal surgery) and 35 kg/m² (transvaginal surgery); (4) no vaginal stenosis or adhesions in female patients undergoing transvaginal specimen extraction; and (5) patients with redundant colon aged 18-70 years and a history of intractable constipation for more than 10 years. Exclusion criteria: (1) colorectal cancer with intestinal perforation or obstruction, or gastric cancer with gastric perforation, gastric hemorrhage, or pyloric obstruction; (2) simultaneous resection of lung, bone, or liver metastases ; (3) history of major abdominal surgery or intestinal adhesions; and (4) incomplete clinical data. From January 2014 to October 2022, 209 patients with gastrointestinal tumors and 25 with redundant colons who met the above criteria were treated by NOSES utilizing a Cai tube (China invention patent number:ZL201410168748.2) in the Department of Gastrointestinal Surgery, Zhongshan Hospital, Xiamen University. The procedures included eversion and pull-out NOSES radical resection in 14 patients with middle and low rectal cancer, NOSES radical left hemicolectomy in 171 patients with left-sided colorectal cancer, NOSES radical right hemicolectomy in 12 patients with right-sided colon cancer, NOSES systematic mesogastric resection in 12 patients with gastric cancer, and NOSES subtotal colectomy in 25 patients with redundant colons. All specimens were collected by using an in-house-made anal cannula (Cai tube) with no auxiliary incisions. The primary outcomes included 1-year recurrence-free survival (RFS) and postoperative complications. Results: Among 234 patients, 116 were male and 118 were female. The mean age was (56.6±10.9) years. NOSES was successfully completed in all patients without conversion to open surgery or procedure-related death. The negative rate of circumferential resection margin was 98.8% (169/171) with both two positive cases having left-sided colorectal cancer. Postoperative complications occurred in 37 patients (15.8%), including 11 cases (4.7%) of anastomotic leakage, 3 cases(1.3%) of anastomotic bleeding, 2 cases (0.9%) of intraperitoneal bleeding, 4 cases (1.7%) of abdominal infection, and 8 cases (3.4%) of pulmonary infection. Reoperations were required in 7 patients (3.0%), all of whom consented to creation of an ileostomy after anastomotic leakage. The total readmission rate within 30 days after surgery was 0.9% (2/234). After a follow-up of (18.3±3.6) months, the 1-year RFS was 94.7%. Five of 209 patients (2.4%) with gastrointestinal tumors had local recurrence, all of which was anastomotic recurrence. Sixteen patients (7.7%) developed distant metastases, including liver metastases(n=8), lung metastases(n=6), and bone metastases (n=2). Conclusion: NOSES assisted by Cai tube is feasible and safe in radical resection of gastrointestinal tumors and subtotal colectomy for redundant colon.
Humans ; Male ; Female ; Middle Aged ; Aged ; Anastomotic Leak/surgery* ; Stomach Neoplasms/surgery* ; Retrospective Studies ; Laparoscopy ; Rectal Neoplasms/surgery* ; Colectomy ; Postoperative Complications ; Liver Neoplasms/surgery* ; Treatment Outcome

Objective: This cross-sectional investigation aimed to determine the incidence, clinical characteristics, prognosis, and related risk factors of olfactory and gustatory dysfunctions related to infection with the SARS-CoV-2 Omicron strain in mainland China. Methods: Data of patients with SARS-CoV-2 from December 28, 2022, to February 21, 2023, were collected through online and offline questionnaires from 45 tertiary hospitals and one center for disease control and prevention in mainland China. The questionnaire included demographic information, previous health history, smoking and alcohol drinking, SARS-CoV-2 vaccination, olfactory and gustatory function before and after infection, other symptoms after infection, as well as the duration and improvement of olfactory and gustatory dysfunction. The self-reported olfactory and gustatory functions of patients were evaluated using the Olfactory VAS scale and Gustatory VAS scale. Results: A total of 35 566 valid questionnaires were obtained, revealing a high incidence of olfactory and taste dysfunctions related to infection with the SARS-CoV-2 Omicron strain (67.75%). Females(χ2=367.013, P<0.001) and young people(χ2=120.210, P<0.001) were more likely to develop these dysfunctions. Gender(OR=1.564, 95%CI: 1.487-1.645), SARS-CoV-2 vaccination status (OR=1.334, 95%CI: 1.164-1.530), oral health status (OR=0.881, 95%CI: 0.839-0.926), smoking history (OR=1.152, 95%CI=1.080-1.229), and drinking history (OR=0.854, 95%CI: 0.785-0.928) were correlated with the occurrence of olfactory and taste dysfunctions related to SARS-CoV-2(above P<0.001). 44.62% (4 391/9 840) of the patients who had not recovered their sense of smell and taste also suffered from nasal congestion, runny nose, and 32.62% (3 210/9 840) suffered from dry mouth and sore throat. The improvement of olfactory and taste functions was correlated with the persistence of accompanying symptoms(χ2=10.873, P=0.001). The average score of olfactory and taste VAS scale was 8.41 and 8.51 respectively before SARS-CoV-2 infection, but decreased to3.69 and 4.29 respectively after SARS-CoV-2 infection, and recovered to 5.83and 6.55 respectively at the time of the survey. The median duration of olfactory and gustatory dysfunctions was 15 days and 12 days, respectively, with 0.5% (121/24 096) of patients experiencing these dysfunctions for more than 28 days. The overall self-reported improvement rate of smell and taste dysfunctions was 59.16% (14 256/24 096). Gender(OR=0.893, 95%CI: 0.839-0.951), SARS-CoV-2 vaccination status (OR=1.334, 95%CI: 1.164-1.530), history of head and facial trauma(OR=1.180, 95%CI: 1.036-1.344, P=0.013), nose (OR=1.104, 95%CI: 1.042-1.171, P=0.001) and oral (OR=1.162, 95%CI: 1.096-1.233) health status, smoking history(OR=0.765, 95%CI: 0.709-0.825), and the persistence of accompanying symptoms (OR=0.359, 95%CI: 0.332-0.388) were correlated with the recovery of olfactory and taste dysfunctions related to SARS-CoV-2 (above P<0.001 except for the indicated values). Conclusion: The incidence of olfactory and taste dysfunctions related to infection with the SARS-CoV-2 Omicron strain is high in mainland China, with females and young people more likely to develop these dysfunctions. Active and effective intervention measures may be required for cases that persist for a long time. The recovery of olfactory and taste functions is influenced by several factors, including gender, SARS-CoV-2 vaccination status, history of head and facial trauma, nasal and oral health status, smoking history, and persistence of accompanying symptoms.
Female ; Humans ; Adolescent ; SARS-CoV-2 ; Smell ; COVID-19/complications* ; Cross-Sectional Studies ; COVID-19 Vaccines ; Incidence ; Olfaction Disorders/etiology* ; Taste Disorders/etiology* ; Prognosis

Objective: To investigate the incidence and trend of short-term outcomes among preterm infants born <34 weeks' gestation. Methods: A secondary analysis of data from the standardized database established by a multicenter cluster-randomized controlled study "reduction of infection in neonatal intensive care units (NICU) using the evidence-based practice for improving quality (REIN-EPIQ) study". This study was conducted in 25 tertiary NICU. A total of 27 192 infants with gestational age <34 weeks at birth and admitted to NICU within the first 7 days of life from May 2015 to April 2018 were enrolled. Infants with severe congenital malformation were excluded. Descriptive analyses were used to describe the mortality and major morbidities of preterm infants by gestational age groups and different admission year groups. Cochran-Armitage test and Jonckheere-Terpstra test were used to analyze the trend of incidences of mortality and morbidities in 3 study-years. Multiple Logistic regression model was constructed to analyze the differences of outcomes in 3 study-years adjusting for confounders. Results: A total of 27 192 preterm infants were enrolled with gestational age of (31.3±2.0) weeks at birth and weight of (1 617±415) g at birth. Overall, 9.5% (2 594/27 192) of infants were discharged against medical advice, and the overall mortality rate was 10.7% (2 907/27 192). Mortality for infants who received complete care was 4.7% (1 147/24 598), and mortality or any major morbidity was 26.2% (6 452/24 598). The incidences of moderate to severe bronchopulmonary dysplasia, sepsis, severe intraventricular hemorrhage or periventricular leukomalacia, proven necrotizing enterocolitis, and severe retinopathy of prematurity were 16.0% (4 342/27 192), 11.9% (3 225/27 192), 6.8% (1 641/24 206), 3.6% (939/25 762) and 1.5% (214/13 868), respectively. There was a decreasing of the overall mortality (P<0.001) during the 3 years. Also, the incidences for sepsis and severe retinopathy of prematurity both decreased (both P<0.001). However, there were no significant differences in the major morbidity in preterm infants who received complete care during the 3-year study period (P=0.230). After adjusting for confounders, infants admitted during the third study year showed significantly lower risk of overall mortality (adjust OR=0.62, 95%CI 0.55-0.69, P<0.001), mortality or major morbidity, moderate to severe bronchopulmonary dysplasia, sepsis and severe retinopathy of prematurity, compared to those admitted in the first study year (all P<0.05). Conclusions: From 2015 to 2018, the mortality and major morbidities among preterm infants in Chinese NICU decreased, but there is still space for further efforts. Further targeted quality improvement is needed to improve the overall outcome of preterm infants.
Bronchopulmonary Dysplasia/epidemiology* ; Gestational Age ; Humans ; Infant ; Infant Mortality/trends* ; Infant, Newborn ; Infant, Premature ; Infant, Premature, Diseases/epidemiology* ; Patient Discharge ; Retinopathy of Prematurity/epidemiology* ; Sepsis/epidemiology*

With the improvement of people's living standard and the change of dietary structure, the prevalence of gout has increased gradually with the increased intake of protein, sugar and fat. There has been a positive correlation between gout and age, and the age of onset decreased gradually. The inflammation induced by sodium urate crystal is the pathological basis of gout, which activates innate immunity, releases many kinds of inflammatory mediators, such as interleukin(IL)-1β, IL-6 and tumor necrosis factor(TNF)-α, and then causes inflammatory cascade reaction and acute attacks, such as joint redness, swelling and heat pain. There is a spontaneous remission mechanism in gout. For one thing, macrophages reduce the stimulation of monosodium urate(MSU) through phagocytosis of MSU crystals as foreign bodies, for another, differentiated and mature macrophages secrete anti-inflammatory factor transforming growth factor(TGF)-β₁, inhibit the expression of inflammatory factors and promote spontaneous relief of acute gout attack. In addition to the activation mechanism of intracellular signaling molecules associated with inflammatory response, the inflammatory mechanism of gout also involves complement activation, cell activation and other pathways. The complications caused by gout, such as cardiovascular system damage and joint destruction, are seriously harmful to human health. At present, western drugs, such as allopurinol and febuxostat, exert an effect in inhibiting xanthine oxidase. Benzimarone has effect in reducing renal absorption of uric acid and promoting uric acid excretion by inhibiting uric acid transporter 1(URAT1) and glucose transporter 9(GLUT9). Even Lesinurad and other medicines in current studies are based on the inhibition of uric acid re-absorption, but with adverse reactions that limit the clinical application. The treatment of gout with traditional Chinese medicine(TCM) has multi-target characteristics, with advantages in reducing uric acid, resisting inflammation and improving joint function and a high safety. It has been gradually popularized and applied in clinical treatment of gout. Therefore, it is a promising research direction to treat gout with TCM and western medicine based on the pathomechanism of gout.

Objective: Several COVID-19 patients have overlapping comorbidities. The independent role of each component contributing to the risk of COVID-19 is unknown, and how some non-cardiometabolic comorbidities affect the risk of COVID-19 remains unclear. Methods: A retrospective follow-up design was adopted. A total of 1,160 laboratory-confirmed patients were enrolled from nine provinces in China. Data on comorbidities were obtained from the patients' medical records. Multivariable logistic regression models were used to estimate the odds ratio ( Results: Overall, 158 (13.6%) patients were diagnosed with severe illness and 32 (2.7%) had unfavorable outcomes. Hypertension (2.87, 1.30-6.32), type 2 diabetes (T2DM) (3.57, 2.32-5.49), cardiovascular disease (CVD) (3.78, 1.81-7.89), fatty liver disease (7.53, 1.96-28.96), hyperlipidemia (2.15, 1.26-3.67), other lung diseases (6.00, 3.01-11.96), and electrolyte imbalance (10.40, 3.00-26.10) were independently linked to increased odds of being severely ill. T2DM (6.07, 2.89-12.75), CVD (8.47, 6.03-11.89), and electrolyte imbalance (19.44, 11.47-32.96) were also strong predictors of unfavorable outcomes. Women with comorbidities were more likely to have severe disease on admission (5.46, 3.25-9.19), while men with comorbidities were more likely to have unfavorable treatment outcomes (6.58, 1.46-29.64) within two weeks. Conclusion Besides hypertension, diabetes, and CVD, fatty liver disease, hyperlipidemia, other lung diseases, and electrolyte imbalance were independent risk factors for COVID-19 severity and poor treatment outcome. Women with comorbidities were more likely to have severe disease, while men with comorbidities were more likely to have unfavorable treatment outcomes.
Adult ; Aged ; COVID-19/virology* ; China/epidemiology* ; Comorbidity ; Female ; Humans ; Male ; Middle Aged ; Retrospective Studies ; Severity of Illness Index ; Treatment Outcome

OBJECTIVETo observe the effect of Compound Zhajin Granule (CZG) on Toll-like re-ceptor 4 (TLR4) signaling pathway in high-fructose corn syrup induced NASH mice.

METHODSThirty 6-week-old male C3H mice were divided into the high fat and high fructose (HFHFr) group (n = 20) and the control group (n = 10) according to body weight. Mice in the HFHFr group ate high fat diet and drank 20% fructose water, while those in the control group ate common diet and drank common water. After 8 weeks mice in the HFHFr group were divided into two group according to body weight, the HFHFr group and the CZG group, 10 in each group. Mice in the CZG group were fed with high fat forage and 20% fructose water, and administered with 50 mL/kg 12. 8% CZG (prepared by hawthorn, Radix Curcumae, Alisma Orientale, Fritillaria Thunbergii, Silybum Marianum, peach seed in the ratio of 3:1.5:1.5:2:1.5:2:1) by gastrogavage. Mice in the HFHFr group were fed in the same way and daily administered with equal volume of distilled water by gastrogavage. Sixteen weeks later all mice were sacrificed. Body weight, liver wet weight, liver function, and lipid metabolism were detected. Pathological changes of liver tissues were assessed by HE staining, oil red O staining, and Masson staining. Expressions of TLR4, myeloid differentiation factor 88 (MyD88), tumor necrosis factor-alpha (TNF-α) were detected using immunohistochemical staining and real-time fluorescent quantitative PCR.

RESULTSBody weight, alanine aminotransferase (ALT), aspartate aminotransferase (AST) were obviously lower in the CZG group than in the HFHFr group (P < 0.05); oil red O stained area and density were decreased more in the CZG group than in the control group. HE staining showed ballooning inflammation was reduced more in the CZG group than in the HFHFr group. Masson staining was negative. Positive rates of TLR4 and MyD88 and mRNA expressions were significantly lower in the CZG group than in the HFHFr group (all P < 0.05).

CONCLUSIONCZG could significantly inhibit TLR4 signaling pathway of liver in NASH mice.

Alanine Transaminase ; metabolism ; Animals ; Aspartate Aminotransferases ; metabolism ; Diet, High-Fat ; Drugs, Chinese Herbal ; pharmacology ; Fructose ; administration & dosage ; adverse effects ; Inflammation ; Lipid Metabolism ; Male ; Mice ; Mice, Inbred C3H ; Myeloid Differentiation Factor 88 ; metabolism ; Non-alcoholic Fatty Liver Disease ; drug therapy ; Signal Transduction ; drug effects ; Toll-Like Receptor 4 ; metabolism ; Tumor Necrosis Factor-alpha ; metabolism

BACKGROUNDWith the progress of perinatal medicine and neonatal technology, more and more extremely low birth weight (ELBW) survived all over the world. This study was designed to investigate the short-term outcomes of ELBW infants during their Neonatal Intensive Care Unit (NICU) stay in the mainland of China.

METHODSAll infants admitted to 26 NICUs with a birth weight (BW) < l000 g were included between January l, 2011 and December 31, 2011. All the data were collected retrospectively from clinical records by a prospectively designed questionnaire. The data collected from each NICU transmitted to the main institution where the results were aggregated and analyzed. Categorical variables were performed with Pearson Chi-square test. Binary Logistic regression analysis was used to detect risk factors.

RESULTSA total of 258 ELBW infants were admitted to 26 NICUs, of whom the mean gestational age (GA) was 28.1 ± 2.2 weeks, and the mean BW was 868 ± 97 g. The overall survival rate at discharge was 50.0%. Despite aggressive treatment 60 infants (23.3%) died and another 69 infants (26.7%) died after medical care withdrawal. Furthermore, the survival rate was significantly higher in coastal areas than inland areas (53.6% vs. 35.3%, P = 0.019). BW < 750 g and GA < 28 weeks were the largest risk factors, and being small for gestational age was a protective factor related to mortality. Respiratory distress syndrome was the most common complication. The incidence of patent ductus arteriosus, intraventricular hemorrhage, periventricular leukomalacia, bronchopulmonary dysplasia, retinopathy of prematurity was 26.2%, 33.7%, 6.7%, 48.1%, and 41.4%, respectively. Ventilator associated pneumonia was the most common hospital acquired infection during hospitalization.

CONCLUSIONSOur study was the first survey that revealed the present status of ELBW infants in the mainland of China. The mortality and morbidity of ELBW infants remained high as compared to other developed countries.

China ; Female ; Humans ; Infant ; Infant Mortality ; Infant, Extremely Low Birth Weight ; Infant, Newborn ; Intensive Care Units, Neonatal ; statistics & numerical data ; Male ; Morbidity ; Respiratory Distress Syndrome, Newborn ; mortality ; Retrospective Studies ; Surveys and Questionnaires

OBJECTIVETo explore the central mechanism of postoperative fatigue syndrome by detecting the expression of NMDA receptor and tryptophan metabolism.

METHODSAfter being numbered according to the weight, ninety-six male SD rats were randomly divided into control group (bowel loop was flipped after laparotomy and received intraperitoneal injection of saline at a dose of 1 ml/kg), POFS model(70% of the length of small intestine was resected and received intraperitoneal injection of saline at a dose of 1 ml/kg), and NMDA antagonist groups(70% of the length of small intestine was resected and received intraperitoneal injection of MK801 at a dose of 1 ml/kg). Each group was divided into subgroups by postoperative 1, 3, 5 and 7 d, with 8 rats in each subgroup. The hippocampus was removed at each time point after open field test (OFT) to detect the mRNA expression levels of NMDA receptor 1 and kynurenine aminotransferase III((KATIII() by real-time PCR. Protein level of NMDA receptor 1 was detected by Western blot. High performance liquid chromatography (HPLC) was used to measure the concentrations of tryptophan (TRP), kynurenine (KYN) and kynurenic acid(KYNA). Ultra-structural changes of hippocampal neurons were observed by transmission electron microscopy(TEM).

RESULTSAs compared to control group, exercise score decreased(P<0.05), rest time and central panel residence time prolonged, periphery/central panel ratio increased (all P<0.05), mRNA and protein expressions of NMDA receptor 1 increased (P<0.05), mRNA expression of KAT III( decreased (P<0.05), KYN/TRP ratio and KYN/KYNA ratio decreased (all P<0.05) in POFS group on postoperative day 1 and 3. As compared to POFS group, central panel residence time and periphery/central panel ratio decreased on postoperative day 1, and mRNA and protein expressions of NMDA receptor 1 decreased on postoperative day 1 and 3 (all P<0.05) in antagonist group. TEM revealed that degenerated neuron was found in the hippocampus of POFS rats, while such damage was improved in antagonist group.

CONCLUSIONThe increased expression level of NMDA receptor may play an important role in POFS. NMDA receptor antagonist MK801 may improve the POFS.

Animals ; Fatigue ; Hippocampus ; Humans ; Injections, Intraperitoneal ; Male ; Postoperative Period ; Rats ; Rats, Sprague-Dawley ; Receptors, N-Methyl-D-Aspartate ; Signal Transduction ; Transaminases

Objective To explore the central mechanism of postoperative fatigue syndrome by detecting the expression of NMDA receptor and tryptophan metabolism. Methods After being numbered according to the weight, ninety-six male SD rats were randomly divided into control group (bowel loop was flipped after laparotomy and received intraperitoneal injection of saline at a dose of 1 ml/kg ), POFS model (70% of the length of small intestine was resected and received intraperitoneal injection of saline at a dose of 1 ml/kg), and NMDA antagonist groups (70% of the length of small intestine was resected and received intraperitoneal injection of MK801 at a dose of 1 ml/kg ). Each group was divided into subgroups by postoperative 1, 3, 5 and 7 d, with 8 rats in each subgroup. The hippocampus was removed at each time point after open field test (OFT) to detect the mRNA expression levels of NMDA receptor 1 and kynurenine aminotransferase Ⅲ (KATⅢ) by real-time PCR. Protein level of NMDA receptor 1 was detected by Western blot. High performance liquid chromatography (HPLC) was used to measure the concentrations of tryptophan (TRP), kynurenine (KYN) and kynurenic acid(KYNA). Ultra-structural changes of hippocampal neurons were observed by transmission electron microscopy (TEM). Results As compared to control group, exercise score decreased (P<0.05), rest time and central panel residence time prolonged, periphery/central panel ratio increased (all P<0.05), mRNA and protein expressions of NMDA receptor 1 increased (P<0.05), mRNA expression of KAT Ⅲ decreased (P<0.05), KYN/TRP ratio and KYN/KYNA ratio decreased (all P<0.05) in POFS group on postoperative day 1 and 3. As compared to POFS group, central panel residence time and periphery/central panel ratio decreased on postoperative day 1 , and mRNA and protein expressions of NMDA receptor 1 decreased on postoperative day 1 and 3 (all P<0.05) in antagonist group. TEM revealed that degenerated neuron was found in the hippocampus of POFS rats , while such damage was improved in antagonist group. Conclusion The increased expression level of NMDA receptor may play an important role in POFS. NMDA receptor antagonist MK801 may improve the POFS.