Association of β-cell function and insulin sensitivity with fasting and 2-h plasma glucose in a large Chinese population

AIM

Our aim was to provide a quantitative analysis of the changes in the principal determinants of insulin sensitivity and secretion in relation to fasting plasma glucose (FPG) or 2-h plasma glucose (2h PG) in a Chinese population with a wide range of glucose tolerance.

METHODS

A total of 5728 adults spanning the entire range of glucose tolerance were included. Insulin sensitivity was measured by Matsuda insulin sensitivity index (ISI(M)) and homeostasis model assessment of 1/homeostasis model assessment of insulin resistance (HOMA-IR). β-Cell function adjusted by insulin sensitivity was assessed from disposition index (DI) at early-phase DI(30) and total DI(120). The exponential curve was established as the best fit for the relationship between insulin sensitivity or β-cell function and FPG or 2h PG.

RESULTS

Relative to the trend classified as increasing 2h PG, hepatic insulin sensitivity and insulin secretion showed a decreasing trend to a substantial degree as FPG increased. A 1 mmol/l increase in FPG and 2h PG concentration was associated with a -22 and -21% decline in ISI(M), -16 and -4% in 1/HOMA-IR, -38 and -35% in DI(30) and -36 and -26% in DI(120). The decay constant of ISI(M) and DI(30) in IFG or ISI(M), 1/HOMA-IR, DI(30) and DI(120) in IGT was lower than that in normal glucose tolerance. Significant interactions between sex and glucose levels determining DI were found.

CONCLUSIONS

We conclude that impairment of insulin sensitivity and insulin secretion contributes to both FPG or 2h PG hyperglycaemia in a Chinese population, but that the decline in insulin secretion is more pronounced with increasing fasting than 2h PG.

A Bayesian approach to risk-adjusted outcome monitoring in healthcare

Clinical outcomes are commonly monitored in healthcare practices to detect changes in care providers' performance. One key challenge in outcome monitoring is the need of adjustment for patient base-line risks. Various control charting methods have been developed to conduct risk-adjusted outcome monitoring, but they all rely on the availability of a large number of historical data. We propose a Bayesian approach to this type of monitoring for cases where historical data are not available. In our approach, detection of change is formulated as a model-selection problem and solved using a popular Bayesian tool for variable selection, the Bayes factor. Issues in decision-making about whether there is a change point in the observed patient outcomes are addressed, including specification of priors and computation of Bayes factors. This approach is applied to a real data set on cardiac surgeries, and its performance under different parameter scenarios is studied through simulations.

Update on the systematic review of palliative radiotherapy trials for bone metastases

AIMS

To update previous meta-analyses of randomised palliative radiotherapy trials comparing single fractions versus multiple fractions.

MATERIALS AND METHODS

All published randomised controlled trials comparing single fraction versus multiple fraction schedules for the palliation of uncomplicated bone metastases were included in this analysis. Odds ratios and 95% confidence intervals were calculated for each trial. Forest plots were created using a random effects model and the Mantel-Haenszel statistic.

RESULTS

In total, 25 randomised controlled trials were identified. For intention-to-treat patients, the overall response rate was similar in patients receiving single fractions (1696 of 2818; 60%) and multiple fractions (1711 of 2799; 61%). Complete response rates were 620 of 2641 (23%) in the single fraction arm and 634 of 2622 (24%) in the multiple fraction arm. No significant difference was seen in overall or complete response rates. Pathological fracture did not favour either arm, but spinal cord compression trended towards favouring multiple fractions; however, neither was statistically significant (P = 0.72 and P = 0.13, respectively). Retreatment rates favoured patients in the multiple fraction arm, where the likelihood of requiring re-irradiation was 2.6-fold greater in the single fraction arm (95% confidence interval: 1.92-3.47; P < 0.00001). Repeated analyses excluding drop-out patients did not alter these findings. In general, no significant differences in acute toxicities were seen.

CONCLUSION

Overall and complete response rates were similar in both intention-to-treat and assessable patients. Single and multiple fraction regimens provided equal pain relief; however, significantly higher retreatment rates occurred in those receiving single fractions.

Assessment of health-related quality of life with the European Organization for Research and Treatment of Cancer QLQ-C15-PAL after palliative radiotherapy of bone metastases

AIMS

To assess health-related quality of life (HRQOL) after palliative radiotherapy for painful bone metastases using a palliative questionnaire (European Organization for Research and Treatment of Cancer QLQ-C15-PAL).

MATERIALS AND METHODS

Patients scheduled to receive palliative radiotherapy for painful bone metastases (n=178) completed the QLQ-C15-PAL questionnaire before treatment and at week 1, week 2, month 1 and month 2 after the first day of radiotherapy. A partial response (PR) or a complete response (CR) to radiotherapy was defined according to the International Consensus criteria. General linear regression was used to analyse changes in QOL in the entire cohort and within responders and non-responders to radiotherapy at all follow-up periods.

RESULTS

The overall radiotherapy response was 45% at week 1 (n=21) (41% PR, 4% CR), 62% at week 2 (n=28) (58% PR, 4% CR), 62% at month 1 (n=58) (60% PR, 2% CR) and 65% at month 2 (n=38) (60% PR, 5% CR). In general, a significant decrease in pain (P<0.0001), insomnia (P<0.0001) and constipation (P=0.004) was seen by month 1 after radiotherapy. In patients who responded to radiotherapy, overall QOL significantly improved by month 2 after radiotherapy (P=0.002). Radiotherapy responders also reported an improvement in emotional functioning together with a decrease in symptoms such as insomnia and constipation at month 1. No improvements were seen in any of the QLQ-C15-PAL scores for patients whose pain did not respond to radiotherapy.

CONCLUSION

Radiotherapy responders showed not only an improvement in pain, but also in HRQOL as assessed by QLQ-C15-PAL. As early as 1 week after radiotherapy for bone metastases, a pain relief response was reported by patients.

Seroprevalence of hepatitis B virus markers in individuals for physical examination in West China Hospital, China

BACKGROUND

Hepatitis B virus (HBV) is the major cause of chronic hepatitis,cirrhosis, and hepatocellular carcinoma. The global epidemiological scenario of HBV infection has been changing rapidly over the last two decades due to an effective immunization programme initiated by the World Health Organization. The objective of this study is to estimate the prevalence of HBV in apparently adult people who were taken health examination in our Hospital.

METHODS

A cross-sectional seroprevalence analysis of hepatitis B virus infection was performed in 12037 adult residents (aged > or =18 years) in Chengdu, who visited Health Examination Center of West China Hospital of Sichuan University for routine medical check-up during the period from March to December 2008. A structured medical form was used to collect data on demographic characteristics and risk factors. ELISA was used to test sera for HBV markers. Descriptive and logistic regression models were used for analysis.

RESULTS

A total of 12,037 urban residents were involved. Prevalence of positive HBsAg was 6.1%, lower than the level of national seroepidemiological survey in (7.18%). Among HBsAg negative people, anti-HBs and anti-HBc was 60.2% and 13.6% respectively. There was a maximum between 18 to 29 years of age (61.8%) in anti-HBs positive people. Multivariate conditional logistic regressive analysis showed that, except for blood and vertical transmission, factors of male gender (OR, 1.876; 95% CI, 1.519-2.316; P < 0.001) and alcohol intake (OR, 0.689; 95% CI, 0.571-0.832; P < 0.001) were associated with a higher risk of positive HBsAg.

CONCLUSIONS

Among the medical examination people in Chengdu, HBsAg positive rate was lower than the national general population, the epidemiological characteristics of hepatitis B has been changed, because of vacination policies to the newborn; therefore, the necessity to continue to carry on the vaccination program.

Polymorphisms in the toll-like receptor 9 gene associated with sepsis and multiple organ dysfunction after major blunt trauma

BACKGROUND

Toll-like receptor (TLR) 9 is the pattern recognition receptor for microbial DNA. Genetic variation within pattern recognition receptors for bacterial endotoxin and exotoxin has been shown to be associated with the risk of sepsis and organ dysfunction in critical illness. However, little is known about the clinical relevance of TLR9 gene polymorphisms in critical illness.

METHODS

A total of 557 patients with major blunt trauma were included in the study. Genetic variation data for the entire TLR9 gene were obtained from the HapMap Project. The genotypes of TLR9 gene polymorphisms were determined using a pyrosequencing method. Whole peripheral blood samples obtained immediately after admission were stimulated with bacterial DNA and production of tumour necrosis factor (TNF) α was then determined. Sepsis morbidity rate and multiple organ dysfunction (MOD) scores were assessed.

RESULTS

Of five single-nucleotide polymorphisms (SNPs) genotyped, four (rs187084, rs352139, rs352140 and rs352162) existed as common SNPs and were in strong linkage disequilibrium. Both rs187084 and rs352162 were significantly associated with TNF-α production by peripheral blood leucocytes in response to bacterial DNA stimulation and a higher sepsis morbidity rate in patients with major trauma. In addition, the rs352162 polymorphism was significantly associated with MOD scores, whereas rs187084 showed a trend to be associated with MOD score.

CONCLUSION

TLR9 polymorphisms rs187084 and rs352162 might be used to provide relevant risk estimates for the development of sepsis and MOD in patients with major trauma.

Increased numbers of circulating ECs are associated with systemic GVHD

INTRODUCTION

Circulating endothelial cells (ECs) are known to reflect endothelial injury, and endothelial injury is associated with graft-versus-host disease (GVHD). We hypothesised that circulating ECs might be associated with systemic acute graft-versus-host disease (aGVHD).

METHODS

BALB/c (H-2k(d) ) mice were treated with total body irradiation and then infused with C57B/6-derived T-cell-depleted bone marrow (TCD-BM) cells or TCD-BM cells and splenocytes. Cyclosporine was used to prevent aGVHD. Circulating ECs and allogeneic lymphocytes were analysed by flow cytometry at multiple time points. The morphology and ultrastructure of the endothelium were examined by light microscopy or transmission electron microscopy.

RESULTS

The results indicated that the number of circulating ECs peaked at day 5 after lethal irradiation in all mice; allogenic transplanted mice (TCD-BM cells and splenocytes) developed typical aGVHD beginning at day 7, exhibiting both histological and clinical symptoms of disease. Circulating ECs peaked a second time at day 9 with aGVHD progression. However, following the administration of CSA, an absence of or a reduction in the amount of subsequent endothelial injury was observed.

CONCLUSION

Circulating ECs might be associated with systemic aGVHD.

Adult endothelial progenitor cells retain hematopoiesis potential

Hematopoietic stem cells (HSCs) are derived from endothelium in the aortic-gonado-mesonephric (AGM) region during embryogenesis. But little is known about whether endothelial progenitor cells (EPCs) retain hematopoiesis potential after birth. In this study, we isolated adult EPCs from the bone marrow of C57BL/6 mice and identified them with an endothelial functional assay and by the CD31(+) CD133(+) CD45(-/dim) VEGFR2(+) phenotype. EPCs isolated from green fluorescence protein (GFP) transgenic C57BL/6 mice were cotransfused with bone marrow cells from wild-type C57BL/6 mice into lethally irradiated BABL/c mice. One month after transplantation, granulocytes (25.73 ± 5.43%) and lymphocytes (12.68 ± 3.26%) in peripheral blood showed GFP(+), referred to as donor EPC-derived blood cells. After an additional month, the percentage of GFP(+) granulocytes decreased to (3.69 ± 1.43%), whereas the percentage of GFP(+) lymphocytes showed no significant difference. Most of the GFP(+) elements showed a diffuse distribution in the spleen; but some were present as aggregates forming lymphoid nodules. GFP(+) endothelial cells were observed in the liver sinusoids, intestinal villi, and lung of recipient mice. These results indicated that adult EPCs not only took part in vasculogenesis, but also retained hematopoietic ability.

Vascular endothelium changes after conditioning in hematopoietic stem cell transplantation: role of cyclophosphamide and busulfan

Vascular endothelial injury, a feature of some complications of hematopoietic stem cell transplantation (HSCT), is characterized by increased endothelial cells. We investigated that classical pretreatment drugs in HSCT could result in vascular endothelial injury in mice. Six-to eight-week-old female BALB/c mice were divided into a control group, a cyclophosphamide group (60 mg/kg per day for 2 days) and a busulfan group (4 mg/kg per day for 4 days). We observed the general state of health and regularly counted the number of white blood cells. Circulating endothelial cells and their progenitors were estimated by flow cytometry. Morphologic endothelial changes were analyzed with optical and transmission electron microscopy. After conditioning with cyclophosphamide or busulfan, white blood cells fell to a low number with injuries noted on hematoxylin and eosin-stained pathology sections. Circulating endothelial cells and their progenitors peaked significantly higher than in the control group. Vascular endothelial injuries were observed in the 2 experimental groups by transmission electron microscopy. These data support the hypothesis the vascular endothelial injury occurs during conditioning with cyclophosphamide or busulfan for HSCT, with simultaneous mobilization of endothelial progenitor cells.

Palliative response and functional interference outcomes using the Brief Pain Inventory for spinal bony metastases treated with conventional radiotherapy

AIMS

To report pain and functional interference responses in patients radiated for painful spinal metastases, and to determine if location within the vertebral column or dose fractionation are associated with response.

MATERIALS AND METHODS

Patients treated with palliative radiotherapy for symptomatic spinal metastases from May 2003 to June 2005 were analysed. All patients completed the Brief Pain Inventory (BPI) assessment tool at 1, 2 and 3 months after radiotherapy. The pain response was determined using the International Bone Metastases Consensus response definitions. Given seven BPI functional interference items, a Bonferroni adjusted P value of less than 0.007 was considered significant.

RESULTS

One hundred and nine treated patients were assessed. About 50% of patients were treated with a single fraction of 8Gy. All pain scores and functional interference scores significantly decreased over time after radiotherapy. At 3 months, 64% of patients achieved a response. Mood was significantly improved for responders (P=0.003) and a trend in improvement was observed for general activity (P=0.01) and normal work (P=0.04). Breast and prostate primaries were more likely to achieve an early response as compared with a lung primary. Neither location within the vertebral column or radiotherapy dose fractionation independently predicted for pain or functional interference responses.

CONCLUSION

Conventional radiotherapy with 8Gy in a single fraction for spine metastases resulted in effective palliation of pain at 3 months and had a positive effect on a patient's mood. Location within the spine was not a predictive factor.