No association between two polymorphisms of the serotonin transporter gene and combined type attention deficit hyperactivity disorder

Several independent studies have reported association between serotonin transporter gene (SLC6A4) polymorphisms and attention deficit hyperactivity disorder (ADHD). Five studies found evidence for association between the long-allele of a 44-bp insertion/deletion polymorphism (5-HTTLPR) and ADHD. Another two studies corroborated this finding while a further six studies did not find such an association. For a second polymorphism within the gene, a variable number tandem repeat (VNTR) within intron 2, one study demonstrated that the 12/12 genotype was significantly less frequent in ADHD cases compared to controls, while a second study found that the 12-allele was preferentially transmitted to offspring affected with ADHD. To provide further clarification of the reported associations, we investigated the association of these two markers with ADHD in a sample of 1,020 families with 1,166 combined type ADHD cases for the International Multi-Centre ADHD Genetics project, using the Transmission Disequilibrium Test. Given the large body of work supporting the association of the promoter polymorphism and mood disorders, we further analyzed the group of subjects with ADHD plus mood disorder separately. No association was found between either of the two markers and ADHD in our large multisite study or with depression within the sample of ADHD cases.

Cysteinyl leukotriene receptor 1 gene variation and risk of asthma

Although it has been recognised that genetics plays an important role in the development of asthma, important causal loci remain to be identified. The aim of the present study was to examine the association of known and novel candidate genes with asthma. Two independent samples, including 170 asthmatic cases and 347 controls in the initial sample, and 202 asthmatic cases and 332 controls in the confirmation sample, were recruited from the same region of China. Functional single nucleotide polymorphisms (SNPs; n = 129) from 105 genes were genotyped using MassARRAY technology, and 119 SNPs were used for the subsequent analysis. In the initial sample, three SNPs, rs320995 in the cysteinyl leukotriene receptor 1 gene, rs1047266 in the tumour necrosis factor receptor superfamily, member 10b, gene and rs40401 in the interleukin-3 gene, were associated with risk of asthma. Notably, under the recessive genetic model, subjects without the thymidine allele in SNP rs320995 had a 3.1 times higher risk of asthma, which remained significant after accounting for multiple testing. This association was replicated in the confirmation sample and validated by meta-analysis. Further, sex-specific analysis was performed, but no sex difference was found. The present study provided coherent evidence that cysteinyl leukotriene receptor 1 gene variation is associated with risk of asthma.

Comparative disposition of [14C]ertapenem, a novel carbapenem antibiotic, in rat, monkey and man

1. The disposition and metabolism of ertapenem, a carbapenem antibiotic, was examined in rat, monkey and man. Sprague-Dawley rats and Rhesus monkeys were given, by intravenous administration, radiolabelled doses of ertapenem (60 and 30 mg kg(-1), respectively), and healthy normal volunteers received a single fixed dose of 1000 mg. Urine and faeces were collected for determination of total radioactivity. 2. In healthy volunteers, [14C]ertapenem was eliminated by a combination of hydrolytic metabolism to a beta-lactam ring-opened derivative and renal excretion of unchanged drug. Approximately equal amounts were excreted as a beta-lactam ring-opened metabolite and unchanged drug (36.7 and 37.5% of dose, respectively). A secondary amide hydrolysis product accounted for about 1% of the dose in man. About 10% of the administered radioactivity was recovered in faeces, which suggested that a minor fraction underwent biliary and/or intestinal excretion. 3. In animals, a greater fraction of the dose was eliminated via metabolism; excretion of unchanged drug accounted for 17 and 5% of dose in rats and monkeys, respectively. In monkeys, the beta-lactam ring-opened and amide hydrolysis metabolites accounted for 74.8 and 7.59% of the dose, respectively, whereas in rats, these metabolites accounted for 31.9 and 20% of dose, respectively. 4. In vitro studies with fresh rat tissue homogenates indicated that lung and kidney were the primary organs involved in mediating formation of the beta-lactam ring-opened metabolite. The specific inhibitor of dehydropeptidase-I, cilastatin, inhibited the in vivo and in vitro metabolism of ertapenem in rats, which suggested strongly that the hydrolysis of ertapenem in lung and kidney was mediated by this enzyme.

Stereoselective hepatic disposition of a diastereomeric pair of αvβ3antagonists in rat

1. The study investigated mechanisms underlying the stereoselective hepatic disposition observed in rats of a zwitterionic diastereomeric pair ((3S)-3-[(3R or 3S)-2-oxo-3-[3-(5,6,7,8-tetrahydro-1,8-naphthyridin-2-yl)propyl]pyrrolidin-1-yl]-3-quinolin-3-ylpropanoic acid) with different lipophilicities. 2. In a recirculating isolated rat liver system, the more hydrophilic diastereomer II possessed biliary clearance, CLb, and bile-to-liver concentration ratio higher (about 10-30-fold) than the lipophilic zwitterion I, whereas both I and II exhibited comparably high concentration ratios between liver and perfusate. Although MK-571, a known multidrug resistance protein (MRP) inhibitor, significantly inhibited the CLb of both compounds, it did not inhibit their canalicular transport, as evident by unchanged concentration ratios between bile and liver of either I or II. 3. Following an intravenous infusion of I or II to Sprague-Dawley rats, the biliary clearance calculated either based on plasma (CL(b,p)) or liver concentration (CL(b,l)), of II was much higher than that of I (about 5-50-fold). In rats lacking multidrug resistance protein 2 (Mrp2) (Eisai hyperbilirubinemic rat, EHBR), the biliary excretion rate and CL(b,p) of II were also higher than the corresponding values for I. However, both CL(b,p) or CL(b,l) of either I or II were not reduced in EHBR, as compared with control SD rats. 4. In the in vitro rat canalicular membrane vesicle study, I and II exhibited no differences in their inhibitory effect on the Mrp2 mediated ATP-dependent [3H]DNP-SG initial uptake (no inhibition at 10 microM and only about 40% inhibition at 100 microM). 5. Collectively, these results suggested that (1) the difference in the hepatic disposition between the two isomers was due primarily to the difference in their transport mechanism across the canalicular membrane and (2) Mrp2 did not play a major role in the observed differences in the biliary excretion of the diastereomers I and II in rats.

A retrospective study of plasma cell infiltrates in explanted renal allografts

Renal transplantation is the most effective therapy in end-stage renal disease. The prognosis for transplant survival is still determined by rejection. When plasma cells predominate in the cellular infiltrate of allografts in rejection, it is called plasma cell-rich rejection, which has a poor prognosis. To study the correlation between plasma cell infiltration and humoral rejection, and to explore whether the local plasma cells were involved in renal allograft loss we analyzed 40 explanted grafts and 20 specimens removed for other diseases. All specimens were embedded, deparaffined, and stained with hematoxylin eosin (HE) for analysis by immunohistochemistry (IH). Renal allograft rejection was classified according to the Banff 1997 criteria with examinations for C4d deposition and CD138 expression. Positive C4d staining was defined by linear endothelial C4d deposition in > or =25% of cortical peritubular capillaries. The specimens designated as CD138-positive demonstrated strong and diffuse staining characteristics; trace or rare CD138-positive were classified as negative. Our results showed that among 40 renal graft specimens, 17 cases were C4d-positive, 23 cases were CD138-positive, and 13 cases were C4d and CD138 double-positive, namely, 42.5%, 57.5%, and 32.5%, respectively. Among the double-positive cases, there were 2 patients with a diagnosis of acute cellular rejection, 1 with hyperacute rejection, and 10 with chronic humoral rejection. C4d deposition and CD138-positive plasma cell infiltrate were related by a Spearman analysis (r = 0.330; P = .038). In the control group, there was only 1 case showing C4d positive activities. These observations suggested that infiltrated plasma cells in the renal allograft probably participate in humoral rejection through local secretion of antibodies.

Adiposity measures and blood pressure in Chinese children and adolescents

OBJECTIVE

To investigate the association of adiposity measures with blood pressure (BP) in Chinese children and adolescents.

DESIGN

A cross-sectional study.

PARTICIPANTS

1330 boys and 1170 girls aged 6-18 years from a rural population-based cohort of twins studied in Anhui, China, 1998-2000.

OUTCOME MEASURES

Adiposity measures included body mass index (BMI), total body fat and trunk fat assessed by dual-energy x-ray absorptiometry. BMI was divided into fat mass index (FMI) and lean mass index (LMI) in the analysis. Major outcomes included: systolic (S) and diastolic (D) BP. Both linear and logistic regressions were performed to assess gender-specific associations between various adiposity measures and BP, with adjustment for age and height. Generalised estimating equations were used to account for intra-twin pair correlations.

RESULTS

Mean BMI and percentage body fat in children aged 6-11 years were 14.9 kg/m(2) and 9.7%, respectively; corresponding measures in children aged 12-18 years were 17.8 kg/m(2) and 14.2%. Adiposity measures were more strongly associated with SBP (p<0.05 in all age strata) than DBP (p<0.05 only in children aged 6-11 years). Both FMI (beta = 1.26-2.37) and LMI (beta = 1.00-1.71) are associated with SBP across age and gender strata after adjustment for age and height (p<0.05).

CONCLUSIONS

These results indicate that, in this relatively lean population of Chinese children and adolescents, BP, particularly SBP, is positively associated with measures of adiposity. Of all the adiposity measures, BMI is the strongest predictor of BP.

Expression of P2X5 receptors in the mouse CNS

P2X receptors are ATP-gated cationic channels composed of seven known subunits (P2X1-7) which are involved in different functions in neural tissue. The present study investigates the P2X5 receptor expression pattern in the mouse CNS using immunohistochemistry and in situ hybridization histochemistry. The specificity of the immunostaining has been verified by pre-absorption, Western blot and in situ hybridization methods. Heavy P2X5 receptor immunostaining was observed in the mitral cells of the olfactory bulb; cerebral cortex; globus pallidum, anterior cortical amygdaloid nucleus, amygdalohippocampal area of subcortical telencephalon; anterior nuclei, anteroventral nucleus, ventrolateral nucleus of thalamus; supraoptic nucleus, ventromedial nucleus, arcuate nucleus of hypothalamus; substantia nigra of midbrain; pontine nuclei, mesencephalic trigeminal nucleus, motor trigeminal nucleus, ambiguous nucleus, inferior olive, hypoglossal nucleus, dorsal motor vagus nucleus, area postrema of hindbrain; Purkinje cells of cerebellum; and spinal cord. The identification of extensive P2X5 receptor immunoreactivity and mRNA distribution within the CNS of the mouse demonstrated here is consistent with a role for extracellular ATP acting as a fast neurotransmitter.

[Humanistic burden and health resource utilization among neovascular age-related macular degeneration patients in France]

OBJECTIVE

To assess the impact of bilateral neovascular age-related macula degeneration (NV-AMD) on function and health resource utilization (HRU) in France.

PATIENTS AND METHODS

Cross-sectional study including 401 NV-AMD patients and 471 controls conducted in five countries in 2006. In both groups, demographic and clinical data were collected and the National Eye Institute Visual Function Questionnaire (NEI-VFQ-25), the EuroQoL (EQ-5D), the Hospital Anxiety and Depression Scale (HADS), and questionnaires on HRU were administered.

RESULTS

Eighty-seven NV-AMD patients and 92 controls were recruited in France. The mean age of the NV-AMD patients was 79 (range, 65-95), and 64% were female. After adjusting for age, gender, and co-morbidities, compared to controls, NV-AMD patients reported substantially worse vision-related quality of life on the NEI-VFQ (adjusted mean, 44.4 [36.2-52.7] versus 91.8 [86.2-97.5], p<0.0001). HADS anxiety and depression scores were significantly worse in NV-AMD patients (anxiety score, 8.5 [6.3-10.8] versus 5.1 [3.5-6.7] p=0.0005; depression score: 7.1 [5.1-9.1] versus 2.9 [1.5-4.4] p<0.0001). Per patient yearly cost analysis showed significantly higher direct medical costs: 3396 euro versus 85 euro (p<0.0001), and indirect nonmedical-related costs (mainly for assistance with activities of daily living): 2985 euro versus 494 euro (p=0.014).

CONCLUSIONS

NV-AMD patients in France reported substantially worse QoL and more anxiety and depression symptoms. The functional impact of blindness led to significantly higher health resource utilization in the AMD patients, resulting in higher total health costs compared to a similarly aged control group.

No association found between the promoter variants of TNF-alpha and diabetic retinopathy in Chinese patients with type 2 diabetes

PURPOSE

Necrosis tumor factor (TNF) is known to be associated with diabetic retinopathy (DR). The objective of this study was to examine the genetic variations of TNF-alpha and assess their possible relationship to DR in type 2 diabetic patients in the Chinese population.

MATERIALS AND METHODS

We conducted a case-control association study between the promoter variants of TNF-alpha and diabetic retinopathy in Chinese patients with type 2 diabetes. We selected three variants in the promoter region of TNF-alpha, namely rs1800629, rs1041981, and rs2857713.

RESULTS

No individual SNP nor any haplotype was found to be associated with DR in our study.

CONCLUSION

This is the first study to report TNF-alpha polymorphisms in patients with DR in the Chinese population. The results suggest that the variants among the promoter of TNF-alpha are unlikely to play a major role in the susceptibility to DR in Chinese patients with type 2 diabetes.

Influence of acute normovolaemic haemodilution on bispectral index monitoring and propofol dose requirements

BACKGROUND

Numerous medical and physiological conditions that might alter electroencephalography (EEG), such as hypoglycaemia, hypothermia or hypovolaemia, were shown to result in the bispectral Index (BIS) indicating an incorrect hypnotic state. Recently, acute normovolaemic haemodilution (ANH) was shown to be associated with significant impairment of cognitive functions that could alter EEG and consequently BIS monitoring, an EEG derived parameter.

METHODS

In a randomised clinical study, we assessed the effect of ANH on BIS monitoring before induction and after propofol target controlled infusion (TCI) anaesthesia in 45 unmedicated patients randomly allocated to ANH with oxygen insufflation (oxygen group), ANH with air insufflation (air group), or control group.

RESULTS

With ANH, mean BIS values briefly declined in the oxygen group (82+/-4) and air group (84+/-3) before returning to baseline values. The loss of consciousness time was significantly shorter, with fewer propofol TCI dose requirements, and BIS was significantly higher in the oxygen group (1.3+/-0.5 min, 2.41+/-0.15 microg/ml, 73+/-7) and air group (1.2+/-0.6 min, 2.44+/-0.17 microg/ml, 75+/-5), compared with the control group (1.7+/-0.4 min, 2.75+/-0.17 microg/ml, 61+/-5), respectively. Whereas, there was no significant difference in BIS values between the oxygen group (38+/-7), air group (36+/-5) and control group (40+/-6) at propofol TCI 4 microg/ml anaesthesia maintenance.

CONCLUSIONS

BIS values briefly declined with ANH before returning to baseline values before anaesthesia induction. Despite transient ANH enhancement of propofol effect during induction, there was no significant difference in BIS values with or without ANH during propofol maintenance of anaesthesia.

Crocetin improves the insulin resistance induced by high-fat diet in rats

BACKGROUND AND PURPOSE

The amelioration of insulin resistance by treatment with crocetin is closely related to the hypolipidaemic effect. The present study is designed to clarify the insulin-sensitizing mechanism of crocetin by elucidating the mechanism of regulation of lipid metabolism by crocetin.

EXPERIMENTAL APPROACH

Rats given a high-fat diet were treated with crocetin for 6 weeks before hyperinsulinaemic-euglycaemic clamp. 14C-palmitate was used as tracer to track the fate of non-esterified fatty acids or as substrate to measure beta-oxidation rate. Triglyceride clearance in plasma and lipoprotein lipase activity in tissues were tested. Content of lipids in plasma and tissues was determined. Real-time PCR was used to assay the level of mRNA from genes involved in non-esterified fatty acid and triglyceride uptake and oxidation.

KEY RESULTS

Crocetin prevented high-fat-diet induced insulin resistance (increased clamp glucose infusion rate), raised hepatic non-esterified fatty acid uptake and oxidation, accelerated triglyceride clearance in plasma, enhanced lipoprotein lipase activity in liver, and reduced the accumulation of detrimental lipids (DAG and long-chain acyl CoA) in liver and muscle. Genes involved in hepatic lipid metabolism which are regulated by peroxisome proliferator-activated receptor-alpha, were modulated to accelerate lipid uptake and oxidation.

CONCLUSIONS AND IMPLICATIONS

Through regulating genes involved in lipid metabolism, crocetin accelerated hepatic uptake and oxidation of non-esterified fatty acid and triglyceride, and reduced lipid availability to muscle, thus decreasing lipid accumulation in muscle and liver, and consequently improving sensitivity to insulin.