Vitamin D levels in the assessment of Crohn's disease activity and their relation to nutritional status and inflammation.

BACKGROUND: Crohn's disease (CD) is frequently associated with malnutrition, inflammation and a deficiency of vitamin D (VD) with the relationships between these symptoms being poorly defined. VD is a modulator of the immune system and is associated with the onset of CD and disease activity. The level of serum VD may have potential in the assessment of CD activity. This study aimed to evaluate the relationships between VD, nutritional status and inflammation, and to identify more accurate VD thresholds. METHODS: The study included 76 outpatients with CD diagnosed between October 2018 and October 2020 and 76 healthy volunteers. Levels of serum 25(OH)D and nutritional indicators, as well as biochemical and disease activity assessments, were conducted. RESULTS: Patients with CD and healthy participants were found to differ significantly in their 25(OH)D levels as well in levels of nutritional and inflammatory indicators. The optimal VD cut-off value was found to be 46.81 nmol/L for CD development and 35.32 nmol/L for disease activity. Levels of 25(OH)D were correlated with both nutritional status and inflammation. CONCLUSIONS: The VD level is likely to be a useful additional tool in the evaluation of CD patients and predicting the disease activity and clinical response. The VD level may relate both to the nutritional status and levels of inflammation in CD patients, and disease progression.

Lung cancer screening study from a smoking population in Kunming.

OBJECTIVE: Yunnan, China, is a central tobacco-producing region with a large smoking population and an increasing incidence of lung cancer in recent years. This study aimed to understand the incidence of lung cancer and the characteristics of lung nodules on low-dose computed tomography (LDCT) scans of the chest in a long-term smoking population in Kunming. PATIENTS AND METHODS: Long-term smokers in Kunming who were not at risk of evident lung disease symptoms were recruited through recommendation and publicity by the Kunming University of Science and Technology. RESULTS: Among 375 cases eligible for inclusion,14 cases of lung cancer were detected with a detection rate of 3.73% (95% CI: 2.55%-4.27%), including one case of squamous carcinoma, one case of small cell lung cancer, seven cases of adenocarcinoma of the lung and five cases of early-stage lung cancer (35.71%). In the group of < 6 mm solid nodules and < 5 mm non-solid nodules, no lung cancer was detected in 201 cases; lung cancer was detected in 14 cases in 61 cases, and there was a statistical difference between the two groups (p < 0.05). CONCLUSIONS: The lung cancer detection rate in long-term smokers was high, with the type predominantly adenocarcinoma and a high incidence of lung nodules, and increased when solid nodules≥6 mm or non-solid nodules ≥ 5 mm were present. It is recommended that screening for lung cancer by LDCT of the chest be introduced in the male smoking population who meet the risk factors and that screening for lung cancer in women should be redefined as a high-risk factor.

[A descriptive analysis of tea consumption in adult twins in China].

Objective: To describe the distribution characteristics of tea consumption in adult twins recruited in the Chinese National Twin Registry (CNTR) and provide clues to genetic and environmental influences on tea consumption. Methods: Enrolled in CNTR during 2010-2018, 25 264 twin pairs aged 18 years and above were included in subsequent analysis. Random effect models were used to estimate tea consumption in the population and regional distribution characteristics. The concordance rate of the behavior and difference in consumption volume of tea within pairs were also described. Results: The mean age of all subjects was (35.38±12.45) years old. The weekly tea consumers accounted for 17.0%, with an average tea consumption of (3.36±2.44) cups per day. The proportion of weekly tea consumers was higher among males, 50-59 years old, southern, urban, educated, and the first-born in the twin pair (P<0.05), and lower among unmarried individuals (P<0.001). Within-pair analysis showed that the concordance rate of tea consumption of monozygotic (MZ) twins was higher than that of dizygotic (DZ) twins and the overall heritability of tea consumption was 13.45% (11.38%-15.51%). Stratified by the characteristics mentioned above, only in males, the concordance rate of MZ showed a tendency to be greater than that of DZ (all P<0.05). The differences in consumption volume of tea within twin pairs were minor in MZ among males (P<0.05), while the differences were not significant in female twins. Conclusion: There were discrepancies in the distribution of tea consumption among twins of different demographic and regional characteristics. Tea consumption was mainly influenced by environmental factors and slightly influenced by genetic factors. The size of genetic factors varied with gender, age, and region, and gender was a potential modified factor.

[A descriptive analysis on type 2 diabetes in twins in China].

Objective: To describe the distribution characteristics of type 2 diabetes in twins in Chinese National Twin Registry (CNTR), provide clues and evidence for revealing the influence of genetic and environmental factors for type 2 diabetes. Methods: Of all twins registered in the CNTR during 2010-2018, a total 18 855 twin pairs aged ≥30 years with complete registration information were included in the analysis. The random effect model was used to describe the population and area distribution characteristics and concordance of type 2 diabetes in twin pairs. Results: The mean age of the subjects was (42.8±10.2) years, the study subjects included 10 339 monozygotic (MZ) twin pairs and 8 516 dizygotic (DZ) twin pairs. The self-reported prevalence rate of type 2 diabetes was 2.2% in total population and there was no sighificant difference between MZ and DZ. Intra-twin pairs analysis showed that the concordance rate of type 2 diabetes was 38.2% in MZ twin pairs, and 16.0% in DZ twin pairs, the difference was statistically significant (P<0.001). The concordance rate of type 2 diabetes in MZ twin parts was higher than that in DZ twin pairs in both men and women, in different age groups and in different areas (P<0.05). Further stratified analysis showed that in northern China, only MZ twin pairs less than 60 years old were found to have a higher concordance rate of type 2 diabetes compared with DZ twin pairs (P<0.05). In southern China, the co-prevalence rate in male MZ twin pairs aged ≥60 years was still higher than that in DZ twin pairs (P<0.05). Conclusion: The twin pairs in this study had a lower self-reported prevalence of type 2 diabetes than the general population. The study results suggested that genetic factors play a role in type 2 diabetes prevalence in both men and women, in different age groups and in different areas, however, the effect might vary.

[A descriptive analysis on coronary heart disease in adult twins in China].

Objective: To describe the distribution characteristics of coronary heart disease in adult twins recruited from Chinese Twin Registry (CNTR), and provide clues and evidence for the effect of genetic and environmental influences on coronary heart disease. Methods: By using the data of CNTR during 2010-2018, a total of 34 583 twin pairs aged ≥18 years who completed questionnaire survey and had related information were included in the current study to analyze the population and area distribution characteristics of coronary heart disease. Random effect models were used to compare the differences between groups. The concordane rate of coronary heart disease were calculated respectively in monozygotic (MZ) twin pairs and dizygotic (DZ) twin pairs to estimate the heritability. Results: The twin pairs included in this analysis were aged (34.2±12.4) years. The overall prevalence rate of coronary heart disease in twin pairs was 0.7%. Twin pairs who were women, older, obese and lived in northern China had higher prevalence of coronary heart disease (P<0.05). Intra-pair analysis in the same-sex twin pairs found that the concordane rate of coronary heart disease was higher in MZ twin pairs (25.3%) than in DZ twins (7.4%), and the difference was statistically significant (P<0.001). The overall heritability of coronary heart disease was 19.3% (95%CI: 11.8%-26.8%). Stratified by gender, age and area, the concordane rate was still higher in MZ twin pairs than in DZ pairs. Participants who were women, aged 18-30 years or ≥60 years and lived in northern China had a higher heritability of coronary heart disease. Conclusion: The distribution of coronary heart disease in twin pairs differed in populations and areas. The prevalence of coronary heart disease was affected by genetic factors, but the effect varied with age, gender and area.

[Effect of occupational factors on pre-diabetes mellitus among iron and steel workers].

Objective: To investigate the prevalence of pre-diabetes mellitus (PDM) and the impact of occupation-related factors on PDM, among workers from a steel company in Tangshan city, Hebei province. Methods: Clustering sampling method was used to select a steel company and to carry out occupational health-related physical checkup programs for eligible workers who had working in this company for longer than one year. The study began in February and ended up in June, 2017. Workers who were with FPG level as ≤6.9 mmol/L, and free from diabetes, were selected as the subjects for this study. Questionnaires were used and physical examinations and FPG testing conducted. Results: The total number of subjects in this study was 4 173, of which 2 648 appeared as pre-diabetic, with the prevalence rate as 63.4%. Increase of the PDM prevalence was in parallel with the length of service, among the workers. The risk for the pre-diabetes in those who worked more than 8 hours per day was 1.696 times higher than those who worked less than or equal to 8 h/d (95%CI:1.517-1.937). Compared with those workers without exposures to heat, noise or carbon monoxides, the proportion of pre-diabetes appeared higher in workers exposed to heat, noise or CO with OR=1.782 (95%CI: 1.205-2.636), 1.815 (95%CI: 1.209-2.794) and 1.653 (95%CI: 1.158-2.361), respectively. Risks for those who were exposed to heat or noise were higher than those who were free from exposure to any occupational hazards (OR=2.098, 95%CI: 1.296-3.397). Prevalence rates of pre-diabetes in those who were exposed to heat, noise or CO, were higher than that those who were not. Conclusion: Working hours and exposures to heat, noise or CO appeared as influential factors on PDM.

An innovative method based on cloud model learning to identify high-risk pollution intervals of storm-flow on an urban catchment scale.

Identifying high-risk storm-flow pollution intervals in an urban watershed is critical for watershed pollution control decision-making. High-risk pollution intervals of storm-flow are defined as storm-flow intervals that contribute more than the background pollutant load, and whose load contribution rank in the top 20%. However, the identification of high-risk pollution intervals is difficult due to variations in the flow-concentration relationship among rain events, uncertainty inherent in stormwater quality data, and physically-based stormwater models requiring a substantial number of parameters. A new method for identifying high-risk pollution intervals during different rain events is proposed. A dataset of the urban watershed located in Shenzhen, southern China, was used to demonstrate the proposed method. A "cut-pool" strategy was initially used to pre-process the dataset for maximizing valuable information hidden in existing datasets and to investigate the impact of rainfall on flow-concentration relationships. Gaussian cloud distribution was then introduced to capture the trend, dispersing extent and randomness of stormwater quality data at any flow interval. Interval Overlapping Ratio (IOR) and Load contribution of storm-flow high-risk pollution intervals was used to assess the performance of the method. Results show that storm-flow high-risk Chemical Oxygen Demand (COD) pollution intervals of the Shiyan watershed was 0.5-1.5 mm under light rain (0-13 mm), 1-3 mm under moderate rain (13-27 mm) and 5-7 mm under heavy rain (27-43 mm). The accuracy of the identified high-risk pollution intervals (IOR) was 63-66% under light rain, 64-67% under moderate rain. Moreover, COD load can be reduced by 44-48% with high-risk storm-flow under light rain; 43-49% under moderate rain; 32% under heavy rain. This method is very useful for effectively controlling storm-flow pollution on an urban catchment scale.

Overexpression of maelstrom promotes bladder urothelial carcinoma cell aggressiveness by epigenetically downregulating MTSS1 through DNMT3B.

We have recently identified and characterized a novel oncogene, maelstrom (MAEL) from 1q24, in the pathogenesis of hepatocellular carcinoma. In this study, MAEL was investigated for its oncogenic role in urothelial carcinoma of the bladder (UCB) tumorigenesis/aggressiveness and underlying molecular mechanisms. Here, we report that overexpression of MAEL in UCB is important in the acquisition of an aggressive and/or poor prognostic phenotype. In UCB cell lines, knockdown of MAEL by short hairpin RNA is sufficient to inhibit cell growth, invasiveness/metastasis and suppressed epithelial-mesenchymal transition (EMT), whereas ectopic overexpression of MAEL promoted cell growth, invasive and/or metastatic capacity and enhanced EMT both in vitro and in vivo. We further demonstrate that MAEL could induce UCB cell EMT by downregulating a critical downstream target, the metastasis suppressor 1 (MTSS1) gene, ultimately leading to an increased invasiveness of cancer cells. Notably, overexpression of MAEL in UCB cells substantially enhanced the enrichment of DNA methyltrans-ferase (DNMT)3B and histone deacetylase (HDAC)1/2 on the promoter of the MTSS1, and thereby epigenetically suppressing the MTSS1 transcription. Downregulation of MTSS1 by MAEL in UCB cells is partially dependent on DNMT3B. Furthermore, we identify that beside the gene amplification of MAEL, miR-186 is a key negative regulator of MAEL and downregulation of miR-186 is another important mechanism for MAEL overexpression in UCBs. These data suggest that overexpression of MAEL, caused by gene amplification and/or decreased miR-186, has a critical oncogenic role in UCB pathogenesis by downregulation of MTSS1, and MAEL could be used as a novel prognostic marker and/or effective therapeutic target for human UCB.

Characterization of Complete Genome Sequences of a Porcine Endogenous Retrovirus Isolated From China Bama Minipig Reveals an Evolutionary Time Earlier Than That of Isolates From European Minipigs.

BACKGROUND: A porcine endogenous retroviruses (PERV) isolate, PERV-A-BM, was isolated from a Guangxi Bama minipig in China. METHODS: To understand its genetic variation and evolution, the complete PERV-A-BM genome sequences were determined and compared with isolates from different Sus scrofa breeds and porcine cell lines. A total of 69 nucleotide substitutions were found in the full-length genome, including 26 non-synonymous mutations. RESULTS: Phylogenetic trees based on the complete genome sequence as well as the gag, pol, and env gene sequences from 21 PERV isolates demonstrated that the PERV-A-BM was closely related to the EF133960 isolate from Chinese Wuzhishan miniature pigs inbred in Hainan, China, and distantly related to strains isolated from European-born pigs. CONCLUSIONS: The estimation of age in the proviral PERV-A-BM integrating into the host genome reveals that the age of PERV-A-BM is at least 8.3 × 10(6) years, an evolutionary time earlier than that of isolates from European-born pigs.

Effects of flurbiprofen axetil on postoperative serum IL-2 and IL-6 levels in patients with colorectal cancer.

We explored the effects of flurbiprofen axetil on interleukin (IL)-2 and IL-6 levels in postoperative patients with colorectal cancer. A total of 120 patients (American Society of Anesthesiologists I and II) scheduled to undergo colorectal cancer surgery were randomly divided into 3 groups (N = 40 in each group): flurbiprofen axetil group (group F), morphine group (group M), and tramadol group (group T). Group M received 0.1 mg/kg morphine, group T received 1.5 mg/kg tramadol, and group F received 1.5 mg/kg flurbiprofen axetil. Patients in the 3 groups were administered treatments through intravenous injection 10 min before surgery. Serum IL-2 and IL-6 levels were detected. Postoperative adverse reactions were recorded, such as nausea, vomiting, and pruritus. The serum IL-6 level of the 3 groups increased 3 h after surgery. Compared with group M, IL-6 level was higher in group T and group F at 1 day after the surgery, and the differences between group M and the other groups were significant (P < 0.05). Moreover, the incidence of adverse reactions was significantly different among 3 groups (P < 0.05). Flurbiprofen axetil promoted the secretion of IL-2 and inhibited IL-6; additionally, flurbiprofen axetil may have a lower incidence of adverse reactions compared to other treatments.

A novel simple phantom for verifying the dose of radiation therapy.

A standard protocol of dosimetric measurements is used by the organizations responsible for verifying that the doses delivered in radiation-therapy institutions are within authorized limits. This study evaluated a self-designed simple auditing phantom for use in verifying the dose of radiation therapy; the phantom design, dose audit system, and clinical tests are described. Thermoluminescent dosimeters (TLDs) were used as postal dosimeters, and mailable phantoms were produced for use in postal audits. Correction factors are important for converting TLD readout values from phantoms into the absorbed dose in water. The phantom scatter correction factor was used to quantify the difference in the scattered dose between a solid water phantom and homemade phantoms; its value ranged from 1.084 to 1.031. The energy-dependence correction factor was used to compare the TLD readout of the unit dose irradiated by audit beam energies with (60)Co in the solid water phantom; its value was 0.99 to 1.01. The setup-condition factor was used to correct for differences in dose-output calibration conditions. Clinical tests of the device calibrating the dose output revealed that the dose deviation was within 3%. Therefore, our homemade phantoms and dosimetric system can be applied for accurately verifying the doses applied in radiation-therapy institutions.

Subretinal fluid is common in experimental non-arteritic anterior ischemic optic neuropathy.

PURPOSE: Anterior ischemic optic neuropathy (AION) is an important cause of acute vision loss for which several animal models exist. It has been associated with subretinal fluid in a previous study on patients but not yet so in animal models. PATIENTS AND METHODS: A patient presented with acute non-arteritic AION (NAION) and underwent ophthalmic evaluation and testing including fluorescein angiography and spectral-domain optical coherence tomography (SD-OCT). On the basis of the patient's findings, we used SD-OCT circular and volume scans to analyze retinal changes in a murine model of NAION. RESULTS: One week after left eye vision loss, the patient had clinical and imaging findings consistent with NAION. On SD-OCT, there was prominent peripapillary retinal thickening consistent with intra-retinal edema and sub-foveolar fluid. Inspired by the findings in human AION, we looked for similar changes in murine NAION using SD-OCT. The circular scan did not adequately detect the presence of subretinal fluid. Using the 25-line scan, which covered a larger part of the posterior pole, we found that 100% of murine AION resulted in subretinal fluid at day 1. The subretinal fluid resolved by week 1. CONCLUSION: This study detailed a case of clinical NAION associated with intra-retinal and subretinal fluid. We also found that subretinal fluid was common in murine photochemical thrombosis model of AION and could be found far away from the optic disc.

MiR-29c mediates epithelial-to-mesenchymal transition in human colorectal carcinoma metastasis via PTP4A and GNA13 regulation of ß-catenin signaling.

BACKGROUND: Distant metastasis is the major cause of cancer-related death, and epithelial-to-mesenchymal transition (EMT) has a critical role in this process. Accumulating evidence indicates that EMT can be regulated by microRNAs (miRNAs). miR-29c has been implicated as a tumor suppressor in several human cancers. However, the role of miR-29c in the progression of colorectal cancer (CRC) metastasis remains largely unknown. PATIENTS AND METHODS: The expression of miR-29c was examined by qRT-PCR in a cohort of primary CRC (PC) and distant liver metastasis (LM) tissues. A series of in vivo and in vitro assays were carried out in order to elucidate the functions of miR-29c and the molecular mechanisms underlying the pathogenesis of metastatic CRC. RESULTS: miR-29c was markedly downregulated in PCs with distant metastasis and determined to be an independent predictor of shortened patient survival. But LM tissues showed higher levels of miR-29c than that in PC tissues. In CRC cells, miR-29c dramatically suppressed cell migration and invasion abilities in vitro and cancer metastasis in vivo. In addition, miR-29c inhibited EMT and negatively regulated Wnt/ß-catenin signaling pathway. Guanine nucleotide binding protein alpha13 (GNA13) and protein tyrosine phosphatase type IVA (PTP4A) were identified as direct targets of miR-29c, which acted through ERK/GSK3ß/ß-catenin and AKT/GSK3ß/ß-catenin pathways, respectively, to regulate EMT. Furthermore, significant associations between miR-29c, its target genes (GNA13 and PTP4A) and EMT markers were validated in both PC and LM tissues. CONCLUSION: Our findings highlight the important role of miR-29c in regulating CRC EMT via GSK-3ß/ß-catenin signaling by targeting GNA13 and PTP4A and provide new insights into the metastatic basis of CRC.

Dose distributions of an ¹9²Ir brachytherapy source in different media.

This study used MCNPX code to investigate the brachytherapy (192)Ir dose distributions in water, bone, and lung tissue and performed radiophotoluminescent glass dosimeter measurements to verify the obtained MCNPX results. The results showed that the dose-rate constant, radial dose function, and anisotropy function in water were highly consistent with data in the literature. However, the lung dose near the source would be overestimated by up to 12%, if the lung tissue is assumed to be water, and, hence, if a tumor is located in the lung, the tumor dose will be overestimated, if the material density is not taken into consideration. In contrast, the lung dose far from the source would be underestimated by up to 30%. Radial dose functions were found to depend not only on the phantom size but also on the material density. The phantom size affects the radial dose function in bone more than those in the other tissues. On the other hand, the anisotropy function in lung tissue was not dependent on the radial distance. Our simulation results could represent valid clinical reference data and be used to improve the accuracy of the doses delivered during brachytherapy applied to patients with lung cancer.

Longikaurin A, a natural ent-kaurane, induces G2/M phase arrest via downregulation of Skp2 and apoptosis induction through ROS/JNK/c-Jun pathway in hepatocellular carcinoma cells.

Hepatocellular carcinoma (HCC) is the most common form of primary liver cancer, and is also highly resistant to conventional chemotherapy treatments. In this study, we report that Longikaurin A (LK-A), an ent-kaurane diterpenoid isolated from the plant Isodon ternifolius, induced cell cycle arrest and apoptosis in human HCC cell lines. LK-A also suppressed tumor growth in SMMC-7721 xenograft models, without inducing any notable major organ-related toxicity. LK-A treatment led to reduced expression of the proto-oncogene S phase kinase-associated protein 2 (Skp2) in SMMC-7721 cells. Lower Skp2 levels correlated with increased expression of p21 and p-cdc2 (Try15), and a corresponding decrease in protein levels of Cyclin B1 and cdc2. Overexpression of Skp2 significantly inhibited LK-A-induced cell cycle arrest in SMMC-7721 cells, suggesting that LK-A may target Skp2 to arrest cells at the G2/M phase. LK-A also induced reactive oxygen species (ROS) production and apoptosis in SMMC-7721 cells. LK-A induced phosphorylation of c-Jun N-terminal kinase (JNK), but not extracellular signal-regulated kinase and P38 MAP kinase. Treatment with, the JNK inhibitor SP600125 prevented LK-A-induced apoptosis in SMMC-7721 cells. Moreover, the antioxidant N-acetylcysteine prevented phosphorylation of both JNK and c-Jun. Taken together, these data indicate that LK-A induces cell cycle arrest and apoptosis in cancer cells by dampening Skp2 expression, and thereby activating the ROS/JNK/c-Jun signaling pathways. LK-A is therefore a potential lead compound for development of antitumor drugs targeting HCC.

EZH2 supports nasopharyngeal carcinoma cell aggressiveness by forming a co-repressor complex with HDAC1/HDAC2 and Snail to inhibit E-cadherin.

The enhancer of zeste homolog 2 (EZH2) is upregulated and has an oncogenic role in several types of human cancer. However, the abnormalities of EZH2 and its underlying mechanisms in the pathogenesis of nasopharyngeal carcinoma (NPC) remain unknown. In this study, we found that high expression of EZH2 in NPC was associated closely with an aggressive and/or poor prognostic phenotype (P<0.05). In NPC cell lines, knockdown of EZH2 by short hairpin RNA was sufficient to inhibit cell invasiveness/metastasis both in vitro and in vivo, whereas ectopic overexpression of EZH2 supported NPC cell invasive capacity with a decreased expression of E-cadherin. In addition, ablation of endogenous Snail in NPC cells virtually totally prevented the repressive activity of EZH2 to E-cadherin, indicating that Snail might be a predominant mediator of EZH2 to suppress E-cadherin. Furthermore, co-immunoprecipitation (IP), chromatin IP and luciferase reporter assays demonstrated that in NPC cells, (1) EZH2 interacted with HDAC1/HDAC2 and Snail to form a repressive complex; (2) these components interact in a linear fashion, not in a triangular fashion, that is, HDAC1 or HDAC2 bridge the interaction between EZH2 and Snail; and (3) the EZH2/HDAC1/2/Snail complex could closely bind to the E-cadherin promoter by Snail, but not YY1, to repress E-cadherin. The data provided in this report suggest a critical role of EZH2 in the control of cell invasion and/or metastasis by forming a co-repressor complex with HDAC1/HDAC2/Snail to repress E-cadherin, an activity that might be responsible, at least in part, for the development and/or progression of human NPCs.

Anthracyclines disrupt telomere maintenance by telomerase through inducing PinX1 ubiquitination and degradation.

Telomere maintenance is essential for cancer growth. Induction of telomere dysfunction, for example, by inhibition of telomeric proteins or telomerase, has been shown to strongly enhance cancer cells' sensitivity to chemotherapies. However, it is not clear whether modulations of telomere maintenance constitute cancer cellular responses to chemotherapies. Furthermore, the manner in which anti-cancer drugs affect telomere function remains unknown. In this study, we show that anthracyclines, a class of anti-cancer drugs widely used in clinical cancer treatments, have an active role in triggering telomere dysfunction specifically in telomerase-positive cancer cells. Anthracyclines interrupt telomere maintenance by telomerase through the downregulation of PinX1, a protein factor responsible for targeting telomerase onto telomeres, thereby inhibiting telomerase association with telomeres. We further demonstrate that anthracyclines downregulate PinX1 by inducing this protein degradation through the ubiquitin-proteasome-dependent pathway. Our data not only reveal a novel action for anthracyclines as telomerase functional inhibitors but also provide a clue for the development of novel anti-cancer drugs based on telomerase/telomere targeting, which is actively investigated by many current studies.

Functional rescue of experimental ischemic optic neuropathy with αB-crystallin.

PURPOSE: Anterior ischemic optic neuropathy (AION) is an important cause of acute vision loss in adults, and there is no effective treatment. We studied early changes following experimental AION and tested the benefit of a potential treatment. MATERIALS AND METHODS: We induced experimental AION in adult mice and tested the effects of short-term (daily for 3 days) and long-term (every other day for 3 weeks) αB-crystallin (αBC) treatment using histological and serial intracranial flash visual evoked potential recordings. RESULTS: One day after experimental AION, there was swelling at the optic nerve (ON) head and increased expression of αBC, a small heat shock protein important in ischemia and inflammation. This upregulation coincided with microglial and astrocytic activation. Our hypothesis was that αBC may be part of the endogenous protective mechanism against injury, thus we tested the effects of αBC on experimental AION. Daily intraveneous or intravitreal αBC injections did not improve visual evoked potential amplitude or latency at days 1-2. However, αBC treatment decreased swelling and dampened the microglial and astrocytic activation on day 3. Longer treatment with intravenous αBC led to acceleration of visual evoked potential latency over 3 weeks, without improving amplitude. This latency acceleration did not correlate with increased retinal ganglion cell survival but did correlate with complete rescue of the ON oligodendrocytes, which are important for myelination. CONCLUSIONS: We identified αBC as an early marker following experimental AION. Treatment with αBC enhanced this endogenous, post-ischemic response by decreasing microglial activation and promoting ON oligodendrocyte survival.

On tests of rate ratio under standard inverse sampling.

Inverse sampling suggests one continues to sample subjects until a pre-specified number of rare events of interest is observed. It is generally considered to be more appropriate than the usual binomial sampling when the subjects come sequentially, when the response probability is rare, and when maximum likelihood estimators of some epidemiological measures are undefined under binomial sampling. Reliable but conservative exact conditional procedure for the ratio of the response probabilities of subject without the attribute of interest has been studied. However, such a procedure is inapplicable to the risk ratio (i.e., ratio of the response probabilities of subject with the attribute of interest). In this paper, we investigate various test statistics (namely Wald-type, score and likelihood ratio test statistics) for testing non-unity risk ratio under standard inverse sampling scheme, which suggests one continue to sample until the predetermined number of index subjects with the attributes of interest is observed. Both asymptotic and numerical approximate unconditional methods are considered for P-value calculation. Performance of these test procedures are evaluated under different settings by means of Monte Carlo simulation. In general, the Wald-type test statistic is preferable for its satisfactory and stable performance with approximate unconditional procedures. The methodologies are illustrated with a real example from a heart disease study.

Oxidative damage in cerebral vessels of diabetic db/db mice.

BACKGROUND: Oxidative stress in diabetes mellitus has recently received increasing attention as it has been proven to be associated with the development of diabetic vascular complications. Our aim was to examine whether microvascular changes, including oxidative damage, were induced in the brains of diabetic animals. METHODS: The expression of 8-hydroxy-2'-deoxyguanosine (8-OHdG), a marker of oxidative DNA damage, the binding of cationized ferritin, a marker for evaluating endothelial glycocalyx, to the endothelial cells of capillaries and vascular permeability of intravenously injected horseradish peroxidase were examined in the cortices of 12- and 20-week-old db/db and db/+m mice. RESULTS: Immunostaining for 8-OHdG was clearly seen in the vessels of the cortex of 20-week-old db/db mice, but was hardly seen in those of mice in the other groups. The immunopositive area of 8-OHdG was significantly increased in the cortex of 20-week-old db/db mice compared with that of 20-week-old db/+m mice. No extravasated leakage of horseradish peroxidase was seen in any groups of mice, while the numbers of cationized ferritin particles binding to the endothelial cells was significantly decreased in 12- and 20-week-old db/db mice compared with that of db/+m mice at the same age, respectively. CONCLUSION: These findings suggest that changes in endothelial glycocalyx are induced in db/db mice and, in addition, the long-term diabetic condition of these mice induces oxidative DNA damage to the cerebral vessels.