Type IV collagen-derived angiogenesis inhibitor: canstatin low expressing in brain-invasive meningiomas using liquid chromatography-mass spectrometry (LC-MS/MS).

PURPOSE: Brain invasion in meningiomas is considered an indicator of more aggressive behavior and worse prognosis. But the precise definition and the prognostic role of brain invasion remains unsolved duo to lacking a standardized workflow of surgical sampling and the histopathological detection. Searching for molecular biomarker expression correlating with brain invasion, could contribute to establish a molecular pathological diagnosis without problems of subjective interobserver variation and deeply understand the mechanism of brain invasion and develop innovative therapeutic strategies. METHODS: We utilized liquid chromatography tandem mass spectrometry to quantify protein abundances between non-invasive meningiomas (n = 21) and brain-invasive meningiomas (n = 21) spanning World Health Organization grades I and III. After proteomic discrepancies were analyzed, the 14 most up-regulated or down-regulated proteins were recorded. Immunohistochemical staining for glial fibrillary acidic protein and most likely brain invasion-related proteins was performed in both groups. RESULTS: A total of 6498 unique proteins were identified in non-invasive and brain-invasive meningiomas. Canstatin expression in the non-invasive group was 2.1-fold that of the brain-invasive group. The immunohistochemical staining showed canstatin expressed in both groups, and the non-invasive group showed stronger staining for canstatin in the tumor mass (p = 0.0132) than the brain-invasive group, which showed moderate intensity. CONCLUSION: This study demonstrated the low expression of canstatin in meningiomas with brain invasion, a finding that provide a basis for understanding the mechanism of brain invasion of meningiomas and may contribute to establish molecular pathological diagnosis and identify novel therapeutic targets for personalized care.

[Impact of adjuvant chemotherapy on prognosis in intrahepatic cholangiocarcinoma patients underwent radical resection].

Objectives: To investigate the clinical value of adjuvant chemotherapy(ACT) in patients with intrahepatic cholangiocarcinoma(ICC) who underwent radical resection and to explore the optimal population that can benefit from ACT. Methods: A retrospective cohort study method was adopted. The clinical and pathological data of 685 patients with ICC who underwent curative intent resection in 10 Chinese hepatobiliary surgery centers from January 2010 to December 2018 were collected;There were 355 males and 330 females. The age(M(IQR)) was 58(14) years (range: 22 to 83 years). Propensity score matching(PSM) was applied to balance the differences between the adjuvant and non-adjuvant chemotherapy groups. Log-rank test was used to compare the prognosis of the two groups of patients. A Bayesian network recurrence-free survival(RFS) prediction model was constructed using the median RFS time (14 months) as the target variable, and the importance of the relevant prognostic factors was ranked according to the multistate Birnbaum importance calculation. A survival prognostic prediction table was established to analyze the population benefiting from adjuvant chemotherapy. Results: Among 685 patients,214 received ACT and 471 did not receive ACT. A total of 124 pairs of patients were included after PSM, and patients in the ACT group had better overall survival (OS) and RFS than those in the non-ACT group(OS: 32.2 months vs. 18.0 months,P=0.003;RFS:18.0 months vs. 10.0 months,P=0.001). The area under the curve of the Bayesian network RFS prediction model was 0.7124. The results of the prognostic factors in order of importance were microvascular invasion (0.158 2),perineural invasion (0.158 2),N stage (0.155 8),T stage (0.120 9), hepatic envelope invasion (0.090 3),adjuvant chemotherapy (0.072 1), tumor location (0.057 5), age (0.042 3), pathological differentiation (0.034 0), sex (0.029 3), alpha-fetoprotein (0.028 9) and preoperative jaundice (0.008 5). A survival prediction table based on the variables with importance greater than 0.1 (microvascular invasion,perineural invasion,N stage,T staging) and ACT showed that all patients benefited from ACT (increase in the probability of RFS≥14 months from 2.21% to 7.68%), with a more significant increase in the probability of RFS≥14 months after ACT in early-stage patients. Conclusion: ACT after radical resection in patients with ICC significantly prolongs the OS and RFS of patients, and the benefit of ACT is greater in early patients.

[A prognostic model of intrahepatic cholangiocarcinoma after curative intent resection based on Bayesian network].

Objective: To examine a survival prognostic model applicable for patients with intrahepatic cholangiocarcinoma (ICC) based on Bayesian network. Methods: The clinical and pathological data of ICC patients who underwent curative intent resection in ten Chinese hepatobiliary surgery centers from January 2010 to December 2018 were collected.A total of 516 patients were included in the study.There were 266 males and 250 females.The median age(M(QR)) was 58(14) years.One hundred and sixteen cases (22.5%) with intrahepatic bile duct stones,and 143 cases (27.7%) with chronic viral hepatitis.The Kaplan-Meier method was used for survival analysis.The univariate and multivariate analysis were implemented respectively using the Log-rank test and Cox proportional hazard model.One-year survival prediction models based on tree augmented naive Bayesian (TAN) and naïve Bayesian algorithm were established by Bayesialab software according to different variables,a nomogram model was also developed based on the independent predictors.The receiver operating characteristic curve and the area under curve (AUC) were used to evaluate the prediction effect of the models. Results: The overall median survival time was 25.0 months,and the 1-,3-and 5-year cumulative survival rates was 76.6%,37.9%,and 21.0%,respectively.Univariate analysis showed that gender,preoperative jaundice,pathological differentiation,vascular invasion,microvascular invasion,liver capsule invasion,T staging,N staging,margin,intrahepatic bile duct stones,carcinoembryonic antigen,and CA19-9 affected the prognosis(χ2=5.858-54.974, all P<0.05).The Cox multivariate model showed that gender,pathological differentiation,liver capsule invasion,T stage,N stage,intrahepatic bile duct stones,and CA19-9 were the independent predictive factors(all P<0.05). The AUC of the TAN model based on all 19 clinicopathological factors was 74.5%,and the AUC of the TAN model based on the 12 prognostic factors derived from univariate analysis was 74.0%,the AUC of the naïve Bayesian model based on 7 independent prognostic risk factors was 79.5%,the AUC and C-index of the nomogram survival prediction model based on 7 independent prognostic risk factors were 78.8% and 0.73,respectively. Conclusion: The Bayesian network model may provide a relatively accurate prognostic prediction for ICC patients after curative intent resection and performed superior to the nomogram model.

[Analysis of related factors for gallstones related gallbladder intraepithelial neoplasia and establishment of prediction models].

Objective: To evaluate the related factors of gallstones related gallbladder intraepithelial neoplasia(GBIN) and establish the prediction models for gallstones related GBIN. Methods: The clinicopathological data of 750 patients who underwent cholecystectomy for gallstones at Department of Hepatobiliary Surgery of the First Affiliated Hospital of Xi'an Jiaotong University from January 2013 to December 2018 and the postoperative pathological examination showed chronic cholecystitis or GBIN were analyzed retrospectively,including 150 cases of gallstones with GBIN and 600 cases of gallstones with chronic cholecystitis.There were 264 males and 486 females with age of (51.3±14.5) years (range: 18 to 90 years).The related factors for gallstones related GBIN were screened by χ2 test and Logistic regression model,and the prediction models were established based on independent related factors and internal validation was conducted.The original data were randomly divided into a training cohort(526 cases) and a validation cohort(224 cases) at a ratio of 7∶3,and the nomogram and tree augmented naïve Bayes were conducted to establish the prediction model for gallstones related GBIN.The consistency index(C-index),calibration chart,area under the receiver operating characteristic curve(AUC) and confusion matrix were used to evaluate the prediction performance of the two models. Results: Univariate analysis showed that age,gallstones history(years),gallbladder size,whether the gallbladder mucosa smooth or not,whether the gallbladder wall thickened or not,gallstones diameter,and number of gallstones were related factors for the occurrence of gallstones related GBIN (χ²=19.957,8.599,9.724,9.301,8.341,15.288,9.169,all P<0.05).Multivariate analysis showed that age (OR=2.23,95%CI:1.50-3.31,P<0.01),gallbladder size (OR=2.11,95%CI:1.17-3.80,P=0.013),whether the gallbladder mucosa smooth or not (OR=1.80,95%CI=1.13-2.88,P=0.014),gallstones diameter(OR=2.98,95%CI:1.71-5.21,P<0.01),and number of gallstones (OR=2.14,95%CI=1.34-3.42,P<0.01) were independent related factors for the occurrence of gallstones related GBIN; the C-index of the nomogram in training cohort and validation cohort were 0.708 and 0.696,respectively.The AUC of the two models in training cohort were 70.60% and 70.73%,and in validation cohort were 68.14% and 67.47%,respectively.The accuracy of the two models in training cohort were 69.96% and 70.72%,and in validation cohort were 66.96% and 67.41%,respectively. Conclusion: Age,gallbladder size,whether the gallbladder mucosa smooth or not,gallstones diameter and number of gallstones are independent related factors for the occurrence of gallstones related GBIN,and the nomogram and tree augmented naïve Bayes prediction models based on the above factors can be used to predict the occurrence of GBIN.

[The progress on survival prediction model of gallbladder carcinoma].

Gallbladder carcinoma (GBC) is the most common malignancy of the biliary tract, radical resection is the only effective treatment for GBC at present. However, the postoperative effect is still poor. Therefore, identifying the key prognostic factors and establishing an individual and accurate survival prediction model for GBC are critical to prognosis assessment, treatment options and clinical decision support in patients with GBC. The prediction value of current commonly used TNM staging system is limited. Cox regression model is the most commonly used classical survival analysis method, but it is difficult to establish the association between prognostic variables. Nomogram and machine learning techniques including Bayesian network have been used to establish survival prediction model of GBC in recent years, which representing a certain degree of advancement, however, the model precision and clinical application still need to be further verified. The establishment of more accurate survival prediction models for GBC based on machine learning algorithm from Chinese multicenter large sample database to guide the clinical decision-making is the main research direction in the future.

[Analysis of the relationship between the number of lymph nodes examined and prognosis for curatively resected gallbladder carcinoma: a multi-institutional study].

Objective: To examine the role of the number of lymph nodes examined(NLNE) on the prognosis of patients with curatively resected gallbladder carcinoma(GBC). Methods: The clinicopathological data and prognosis of 401 patients with GBC who underwent radical surgery from six institutions of China from January 2013 to December 2017 were analyzed retrospectively. There were 153 males(38.2%) and 248 females(61.8%), with age of (62.0±10.5) years (range: 30-88 years). Fifty-three patients(22.2%) were accompanied by jaundice. All patients underwent radical resection+regional lymphadenectomy.R0 or R1 resection was confirmed by postoperative pathological examination.The different cut-off values of NLNE were determined by the X-tile software, the optimal cut-off values were identified by analyzing the relationship between different cut-off values of NLNE with survival rate. Kaplan-Meier method was used for survival analysis. Univariate and multivariate analysis were implemented respectively using the Log-rank test and Cox proportional hazard model. Results: Among the 401 patients enrolled, 135 cases (33.6%) had lymphatic metastasis, of which 98 cases were in N1 stage(24.4%) and 37 cases were in N2 stage(9.2%).A total of 2 794 NLNE were retrieved, with a median count of 6 (5).The median positive lymph nodes count was 0 (1), and the median positive lymph nodes ratio was 0 (IQR, 0-0.2). Since the 12 and 15 were determined as the cut-off values by X-tile, all patients were divided into three groups of 1-11, 12-15 and ≥16.The 3-year survival rate of the three groups was 45.2%, 74.5%, 12.0% respectively, with statistically significant difference between three groups (χ(2)=10.94, P<0.01). The results of multivariate analysis showed that NLNE was an independent prognostic factor for overall survival (P<0.05). Further analysis was performed specifically for subgroup of T stages. For T1b patients, the prognosis of the NLNE with 1-7 group was significantly better than that of the ≥8 group(χ(2)=4.610, P<0.05). For T2 patients, the prognosis of the TLNE ≥7 group was significantly better than that of 1 -6 group (χ(2)=4.287, P<0.05). For T3 and T4 patients, the prognosis of the TLNE with 12 - 15 group was significantly better than that of 1 -11 group (χ(2)=5.007, P<0.01) and ≥16 group (χ(2)=10.158, P<0.01). Conclusions: The NLNE is an independent factor affecting the prognosis of patients with GBC.For patients with stage T1b,8 lymph nodes should be retrieved; for patients with stage T2,extensive dissection of more than 6 lymph nodes can significantly improve the prognosis.For advanced patients (stages T3 and T4), extensive dissection with 12-15 lymph nodes is recommended. However, it fails to get more survival benefits by dissecting more than 16 lymph nodes.

[Diagnosis and treatment of pancreatic tuberculosis: experiences of 10 cases].

Objectives: To study the clinical characteristics of pancreatic tuberculosis, and therefore to improve the diagnosis and treatment of this disease. Methods: The clinical data of 10 patients with pancreatic tuberculosis form 1990 to 2017 were reviewed, including clinical characteristics, laboratory tests and imaging features. Results: The ten patients aged 28 to 71 (median 56) years. All of them presented varying degrees of abdominal pain and weight loss (3 to 8 kg). Hypo-echoic pancreatic masses were shown by abdominal ultra-sound in 7 cases, and cystic-solid masses with thick wall was shown by abdominal CT scan in 4 cases, but dilatation of the pancreatic duct was found in none of the 10 cases. Hemoglobin levels lower than 12 g/L were found in 6 cases, and ESR more than 20 mm/1 h was present in 7 cases. Four cases received PPD test, but only one was positive. CA19-9 was found to be higher than normal (27 IU/ml) in 3 cases (39.2 IU/ml, 125.7 IU/ml, 88.9 IU/ml respectively). Three cases received T-spot.TB tests, and all the results were positive. Seven cases received laparotomy, and the other 3 received endoscopic ultrasound-guided biopsy. Caseous necrosis and Langerhans cells were found in all the 10 cases. Nine patients were treated by 6 to 12 months' anti-tuberculosis therapies, and at 1-5 years' follow-up, 8 were cured and 1 improved. Conclusions: The manifestations of pancreatic tuberculosis were easy to be confused with other diseases, and therefore a comprehensive understanding of history and careful examinations were important for a correct diagnosis. Once the diagnosis was made, prompt standard anti-tuberculosis therapy could lead to a favorable outcome.

[The epidemiological and clinical characteristics of liver hemangioma in health adults].

Objective: To report the epidemiological and clinical characteristics of liver hemangioma in health adults from a large sample of Health Examination Database. Methods: A retrospective study was performed to analyze the epidemiological and clinical Characteristics of liver hemangioma from people who underwent examination in China-Japan friendship hospital from 2014 to 2016. The analysis was also included the relationship between gender or age and the incidence and tumor size. Results: A total of 83 964 healthy adults (age≥18) were included in the study. The overall incidence of liver hemangioma was 2.95%. There was no significant difference of liver hemangiomas incidence between male which was 3.03%, and which was 2.88% in female. Liver hemangiomas incidence had shown obviously increased with patients' age, as the evidence indicating that the prevalence of liver hemangioma in <30 age group was only 1.87%, and the prevalence of liver hemangioma in 41-50 age group raised to 3.72%. While the size of liver hemangioma in different genders was also increasing with age, the tumor size of liver hemangioma in <30 age group was the smallest. Under 50 years old, the size of female patients' liver hemangioma was larger than that of male patients in each age group. The size of female patients' liver hemangioma had obviously decreased over 60 years old. Conclusion: The progress of liver hemangioma was highly influenced by age and gender.

[The survival prediction model of advanced gallbladder cancer based on Bayesian network: a multi-institutional study].

Objective: To investigate the clinical value of Bayesian network in predicting survival of patients with advanced gallbladder cancer(GBC)who underwent curative intent surgery. Methods: The clinical data of patients with advanced GBC who underwent curative intent surgery in 9 institutions from January 2010 to December 2015 were analyzed retrospectively.A median survival time model based on a tree augmented naïve Bayes algorithm was established by Bayesia Lab software.The survival time, number of metastatic lymph nodes(NMLN), T stage, pathological grade, margin, jaundice, liver invasion, age, sex and tumor morphology were included in this model.Confusion matrix, the receiver operating characteristic curve and area under the curve were used to evaluate the accuracy of the model.A priori statistical analysis of these 10 variables and a posterior analysis(survival time as the target variable, the remaining factors as the attribute variables)was performed.The importance rankings of each variable was calculated with the polymorphic Birnbaum importance calculation based on the posterior analysis results.The survival probability forecast table was constructed based on the top 4 prognosis factors. The survival curve was drawn by the Kaplan-Meier method, and differences in survival curves were compared using the Log-rank test. Results: A total of 316 patients were enrolled, including 109 males and 207 females.The ratio of male to female was 1.0∶1.9, the age was (62.0±10.8)years.There was 298 cases(94.3%) R0 resection and 18 cases(5.7%) R1 resection.T staging: 287 cases(90.8%) T3 and 29 cases(9.2%) T4.The median survival time(MST) was 23.77 months, and the 1, 3, 5-year survival rates were 67.4%, 40.8%, 32.0%, respectively.For the Bayesian model, the number of correctly predicted cases was 121(≤23.77 months) and 115(>23.77 months) respectively, leading to a 74.86% accuracy of this model.The prior probability of survival time was 0.503 2(≤23.77 months) and 0.496 8(>23.77 months), the importance ranking showed that NMLN(0.366 6), margin(0.350 1), T stage(0.319 2) and pathological grade(0.258 9) were the top 4 prognosis factors influencing the postoperative MST.These four factors were taken as observation variables to get the probability of patients in different survival periods.Basing on these results, a survival prediction score system including NMLN, margin, T stage and pathological grade was designed, the median survival time(month) of 4-9 points were 66.8, 42.4, 26.0, 9.0, 7.5 and 2.3, respectively, there was a statistically significant difference in the different points(P<0.01). Conclusions: The survival prediction model of GBC based on Bayesian network has high accuracy.NMLN, margin, T staging and pathological grade are the top 4 risk factors affecting the survival of patients with advanced GBC who underwent curative resection.The survival prediction score system based on these four factors could be used to predict the survival and to guide the decision making of patients with advanced GBC.

Application of Mono- and Disaccharides in Drug Targeting and Efficacy.

Carbohydrates and their conjugates play important roles in many biological processes including fertilization, differentiation, development, immune response, and infection. Their activities are largely dependent on the properties of terminal mono- or disaccharides. Galactose, mannose, fucose, glucose, sialic acid, etc., are commonly used as powerful scaffolds installed on drug molecules for targeting specific tissues including brain, liver, and cancers, and as epitopes for enhancing the targeting of various vaccines. This review focuses on the influence of their structural variations, including changes in sugar type, substituent groups and their positions, as well as length of linker portion, on the targeting of drugs or their efficacy. Particular attention is paid to the targeting properties of mono- and disaccharides applied in drug design and discovery.

MSN-on-a-Chip: Cell-Based Screenings Made Possible on a Small-Molecule Microarray of Native Natural Products.

Standard small-molecule microarrays (SMMs) are not well-suited for cell-based screening assays. Of the few attempts made thus far to render SMMs cell-compatible, all encountered major limitations. Here we report the first mesoporous silica nanoparticle (MSN)-on-a-chip platform capable of allowing high-throughput cell-based screening to be conducted on SMMs. By making use of a glass surface on which hundreds of MSNs, each encapsulated with a different native natural product, were immobilized in spatially defined manner, followed by on-chip mammalian cell growth and on-demand compound release, high-content screening was successfully carried out with readily available phenotypic detection methods. By combining this new MSN-on-a-chip system with small interfering RNA technology for the first time, we discovered that (+)-usniacin possesses synergistic inhibitory properties similar to those of olaparib (an FDA-approved drug) in BRCA1-knockdown cancer cells.

Cloning and association analysis of KIT and EDNRB polymorphisms with dominant white coat color in the Chinese raccoon dog (Nyctereutes procyonoides procyonoides).

The Chinese raccoon dog (Nyctereutes procyonoides procyonoides) is one of the most important fur-bearing animal species. The dominant white individual, a coat color variant in farmed Chinese raccoon dog, shows a completely white phenotype over the entire body. The KIT and EDNRB genes have been reported to be associated with the dominant white coat color in some mammalian species. In the present study, the full-length coding sequences of KIT and EDNRB were amplified from a dominant white and a wild-type Chinese raccoon dog. Sequence analysis revealed that the coding region of KIT and EDNRB in Chinese raccoon dog was 2919 and 1332 base pairs in length (accession No. KM083121 and KM083122), respectively, and 2 single-nucleotide polymorphisms (SNPs; c.600C>T and c.967G>A) in KIT and 1 SNP (c.259A>C) in EDNRB was found only in the dominant white individual. An alternative splicing site at the boundary of 4 and 5 of the KIT gene was identified in both individuals. We further investigated the association between the 3 SNPs of KIT and EDNRB and dominant white coat color by genotyping 18 individuals. We found no association between these SNPs and dominant white coat color. Based on these results, we can exclude the coding regions of the KIT and EDNRB genes as determinants of the dominant white coat color in Chinese raccoon dog.

Gene therapy by membrane-expressed superantigen for alpha-fetoprotein-producing hepatocellular carcinoma.

Staphylococcus enterotoxin A (SEA) is a powerful immunostimulant, which can stimulate T cells bearing certain T-cell receptor beta-chain variable regions, when bound to major histocompatibility complex II molecules. In vivo administration of intact superantigen in sufficient therapeutic amounts risks unwanted cytotoxicity against normal cells. In this study, we used SEA fused with CD80 transmembrane region (named as SEAtm) driven by alpha-fetoprotein (AFP) enhancer/promoter to reduce toxicity and to improve safety and efficiency in the application of SEA. We demonstrated that SEAtm by adenovirus from the AFP enhancer/promoter (AdAFPSEA) could be expressed on the surface of AFP-producing cell line Hepa1-6 instead of non-AFP-producing cell lines. Hepa1-6 infected by recombinant adenovirus stimulated proliferation of splenocytes and activated CD4(+) and CD8(+) T cells in vitro. After AdAFPSEA was injected into the subcutaneously established hepatoma in vivo, the expression of SEA was detected in tumor tissues, which subsequently induced tumor-specific cytotoxic T cells in spleen. Moreover, hepatocellular carcinoma (HCC) xenografts were suppressed by treatment with AdAFPSEA and the survival time of treated mice was prolonged. These findings suggest that membrane-expressed SEA by adenovirus from AdAFPSEA can generate stronger local and systemic antitumor responses against HCC.

Caudoputamen is damaged by hypocapnia during mechanical ventilation in a rat model of chronic cerebral hypoperfusion.

BACKGROUND AND PURPOSE: Postoperative brain dysfunction, such as delirium, is a common complication of anesthesia and is sometimes prolonged, especially in patients with cerebrovascular disease. In the present study we investigated the effect of hypocapnia during anesthesia on neuronal damage using a rat model of chronic cerebral hypoperfusion. METHODS: Chronic cerebral hypoperfusion was induced by clipping the bilateral common carotid arteries in male Wistar rats. Fourteen days after the operation, these animals were mechanically ventilated for 2 hours and then kept in suitable conditions for an additional 14 days. Twenty-four rats were assigned to 4 groups: those with chronic cerebral hypoperfusion with either hypocapnia or normocapnia during anesthesia, and those given sham operation with either hypocapnia or normocapnia. White matter lesions in the brain sections were evaluated with Klüver-Barrera staining. Proliferation of glial cells was estimated with the use of immunohistochemistry of glial fibrillary acidic protein, a marker for astroglia, and CD11b, a marker for microglia. Computer-assisted morphometry was applied to the immunohistochemical results of microtubule-associated protein 2 to evaluate the loss of neurons. RESULTS: The histological damage was localized almost exclusively in the white matter in the rats subjected to chronic cerebral hypoperfusion but without hypocapnia. Neuronal damage and astroglial proliferation occurred with aggravated white matter lesions in the caudoputamen in the rats with chronic cerebral hypoperfusion and hypocapnia. No lesions were observed in sham-operated rats with either hypocapnia or normocapnia. CONCLUSIONS: These results indicate that hypocapnia during anesthesia causes tissue damage in the caudoputamen, which may be responsible for long-lasting postoperative delirium in patients with stroke and/or dementia.

Xenon inhibits but N(2)O enhances ketamine-induced c-Fos expression in the rat posterior cingulate and retrosplenial cortices.

Both nitrous oxide (N(2)O) and xenon are N:-methyl-D-aspartate receptor antagonists that have psychotomimetic effects and cause neuronal injuries in the posterior cingulate and retrosplenial cortices. We investigated the effect of xenon, xenon with ketamine, N(2)O, and N(2)O with ketamine on c-Fos expression in the rat posterior cingulate and retrosplenial cortices, a marker of psychotomimetic effects. Brain sections were prepared, and c-Fos expression was detected with immunohistochemical methods. A loss of microtubule-associated protein 2, a marker of neuronal injury, was also investigated. The number of Fos-like immunoreactivity positive cells by ketamine IV at a dose of 5 mg/kg under 70% N(2)O (128 +/- 12 cells per 0.5 mm(2)) was significantly more than those under 30% (15 +/- 2 cells per 0.5 mm(2)) and 70% xenon (2 +/- 1 cells per 0.5 mm(2)). Despite differences in c-fos immunoreactivity, there was no loss of microtubule-associated protein 2 immunoreactivity in any group examined. Xenon may suppress the adverse neuronal effects of ketamine, and combined use of xenon and ketamine seems to be safe in respect to neuronal adverse effects.

[Effect of -6 degrees head-down-bed-rest on human cellular immune function].

OBJECTIVE: To observe the effect of -6 degrees head-down bed-rest on proliferation of lymphocyte and production of certain cytokines. METHODS: 6 healthy young men served as the subjects. Peripheral blood lymphocyte was assayed 1d prior to and on the 3rd day and 6th day of bed rest. RESULTS: The production of IFN-alpha on the 3rd day was markedly decreased (P < 0.05), but killing activity of NK was significantly enhanced (P < 0.05), production of IFN-gamma and expression of IL-2 receptor were all slightly reduced. Both production of IFN-alpha and killing activity of NK resumed to the control level on the 6th day, production of IFN-r and CD25 were significantly lowered (P < 0.05) on the 6th day, a lymphocyte proliferation and production of IL-2 were gradually decreased with time, but production of IL-6 was gradually increased. CONCLUSION: -6 degrees head-down bed-rested has certain effect on cellular immune function in man.

[Effect of -6 degrees bed-rest on T-lymphocyte proliferation and cytokines production in human].

In this study, the effect of -6 degrees head-down bed-rest on proliferation of T lymphocyte stimulated by phytohemagglutinin, a kind of polyclone T cell activators and cytokines production were observed. The results showed: after 2 d bed-rest, proliferation of T lymphocyte stimulated by phytohemagglutinin decreased significantly; the activity of interleukin-2 trended to decrease; the expression of interleukin-2 receptor tended to increase; the production of interleukin-6 decreased significantly. After 6 d bed-rest, T lymphocyte proliferation restored to normal; the activity of interleukin-2 and expression of interleukin-2 receptor had no change; the production of interleukin-6 decreased significantly. This result demonstrated that -6 degrees bed-rest can decrease T lymphocyte proliferation function, and this decrease may be caused by the reduction of cytokines secretion.

[Study on mechanisms of T lymphocyte function changes in mice under simulated weightlessness in terms of IL-2 and Bcl-2 gene transcription].

To understand the mechanisms of T lymphocyte function changes under simulated weightlessness T lymphocyte proliferation (MTT assay), IL-2 production (biological assay), IL-2 gene (dot blot) and Bcl-2 oncogene (RT-PCR) transcription of splenic cell were observed in mice. The results showed that on the 7 th and 14 th day of simulated weightlessness T lymphocyte proliferation and IL-2 production decreased and significant on the 14 th day; on the 7 th and 14 th day of simulated weightlessness IL-2 and Bcl-2 gene transcription decreased, significant on the 14 day. It demonstrated that simulated weightlessness inhibits IL-2 production by decreasing IL-2 gene transcrition. IL-2 and Bcl-2 gene may be regulators of lymphocyte function under simulated weightlessness.

RAR beta 2-mediated growth inhibition in HeLa cells.

Retinoic acid inhibits the growth of a variety of normal and transformed cells in vitro and in vivo. How retinoic acid inhibits cell growth is poorly understood but involves interactions between the ligand and a series of nuclear and cytoplasmic receptors. The nuclear receptors for retinoic acid are of two types, the RARs and the RXRs. Each can function as a ligand-inducible transcription enhancing factor. In previous studies, we have demonstrated that an isoform of one RAR, RAR beta 2, is transcriptionally up-regulated in senescent human dermal fibroblasts and senescent human mammary epithelial cells. Moreover, we have also shown that RAR beta 2 can inhibit oncogene-induced focus formation, in primary rat embryo fibroblasts, as effectively as the tumor suppressor gene p53. Here, we extend our studies of retinoid-regulated signal transduction pathways that inhibit cell proliferation by demonstrating that HeLa cells expressing an RAR beta 2 construct are growth inhibited by greater than 50% when compared to the parent cell lines. The RAR beta 2-expressing cell lines are inhibited further by the addition of exogenous all-trans-retinoic acid. Finally, soft agar assays show that the RAR beta 2-expressing cell lines also demonstrate an inhibition of growth in soft agar, when compared to the parent growth cell lines, and are inhibited further in the presence of added all-trans-retinoic acid. These data definitively show that RAR beta 2 can inhibit cell proliferation in an established tumor cell line and provide more strength to the notion that this isoform is an effective growth inhibitor in vitro and, most likely, in vivo.

Cellular aging and transformation suppression: a role for retinoic acid receptor beta 2.

Cellular senescence is characterized by a finite proliferative capacity in vitro. Moreover, the proliferative capacity of dermal fibroblasts harvested from humans is inversely proportional to the age of the donor, suggesting that senescence in culture is a manifestation, at the cellular level, of processes that occur during in vivo human aging. As cellular senescence is a program that ultimately decreases cell proliferation, it has been hypothesized that the genetic mechanisms responsible for the negative growth regulation of senescence may also be involved in the suppression of neoplastic transformation. Retinoic acid (RA) and its derivatives are effective negative growth regulators and are known to inhibit tumor growth, in vitro and in vivo. As a first step in examining a role for retinoic acid in the regulation of cellular aging in human fibroblasts, we examined the expression of the nuclear receptors for RA (RAR alpha, RAR beta, and RAR gamma) in human donors of different ages. These studies demonstrate a selective up-regulation of RAR beta, in response to RA, in fibroblasts that manifest a decreased proliferative capacity. We extend these observations to show that this finding is independent of the age of the donor and correlates with the proliferative capacity of the culture as a whole. Nuclear run-on studies show that the increase in RAR beta mRNA accumulation is mediated by a striking increase in the transcription of the RAR beta 2 isoform. Senescent fibroblasts manifesting the transcriptional increase of the RAR beta 2 isoform also demonstrate transcriptional repression of the protooncogene, c-fos. Functional studies demonstrate that RAR beta 2, like the tumor suppressor gene p53, can inhibit oncogene-induced focus formation. These data provide further support for the contention that genetic events important in cellular senescence may also play a significant role in tumor suppression in humans. Moreover, these observations suggest that RA, through transcriptional regulation of RAR beta 2, may mediate aspects of the negative growth control that characterizes both states.