Direct determination of exchange parameters in Cs2CuBr4 and Cs2CuCl4: high-field electron-spin-resonance studies

Spin-1/2 Heisenberg antiferromagnets Cs2CuCl4 and Cs2CuBr4 with distorted triangular-lattice structures are studied by means of electron spin resonance spectroscopy in magnetic fields up to the saturation field and above. In the magnetically saturated phase, quantum fluctuations are fully suppressed, and the spin dynamics is defined by ordinary magnons. This allows us to accurately describe the magnetic excitation spectra in both materials and, using the harmonic spin-wave theory, to determine their exchange parameters. The viability of the proposed method was proven by applying it to Cs2CuCl4, yielding J/kB=4.7(2)  K, J'/kB=1.42(7)  K, [J'/J≃0.30] and revealing good agreement with inelastic neutron-scattering results. For the isostructural Cs2CuBr4, we obtain J/kB=14.9(7)  K, J'/kB=6.1(3)  K, [J'/J≃0.41], providing exact and conclusive information on the exchange couplings in this frustrated spin system.

Microarray analysis of differentially expressed genes in preeclamptic and normal placental tissues

PURPOSE OF INVESTIGATION

To detect the candidate genes for preeclampsia (PE).

MATERIALS AND METHODS

The gene expression profiles in preeclamptic and normal placental tissues were analyzed using cDNA microarray approach and the altered expression of important genes were further confirmed by real-time RT-PCR (reverse transcription polymerase chain reaction) technique. Total RNA was extracted from placental tissues of three cases with severe PE and from three cases with normal pregnancy. After scanning, differentially expressed genes were detected by software.

RESULTS

In two experiments (the fluorescent labels were exchanged), a total of 111 differentially expressed genes were detected. In placental tissue ofpreeclamptic pregnancy, 68 differentially expressed genes were up-regulated, and 44 differentially expressed genes were down-regulated. Of these genes, 16 highly differentially expressed genes were confirmed by real-time fluorescent quantitative RT-PCR, and the result showed that the ratio of gene expression differences was comparable to that detected by cDNA microarray.

CONCLUSION

The results of bioinformatic analysis showed that encoding products of differentially expressed genes were correlated to infiltration of placenta trophoblastic cells, immunomodulatory factors, pregnancy-associated plasma protein, signal transduction pathway, and cell adhesion. Further studies on the biological function and regulating mechanism of these genes will provide new clues for better understanding of etiology and pathogenesis of PE.

Association analysis of the IL2RA gene with alopecia areata in a Chinese population

BACKGROUND

Interleukin-2 receptor subunit alpha (IL2RA) is highly expressed on CD4+CD25+ regulatory T cells and is important for immune homeostasis and the suppression of autoimmune responses. It has been suggested that the single nucleotide polymorphism in IL2RA may affect the pathogenesis of alopecia areata (AA).

OBJECTIVE

Our aim was to investigate the link between IL2RA polymorphism and AA in a Chinese population.

METHODS

We examined 427 patients and 430 controls in this study. The rs3118470 polymorphism was evaluated using high-resolution melting analysis and direct sequencing.

RESULTS

The prevalence of the C/C, T/C and T/T genotypes was 16.2, 48.2 and 35.6%, respectively. The genotype distribution and allele frequencies were significantly different between AA and control subjects (p < 0.0001). The C allele frequency was significantly higher in the AA group (p < 0.0001), and the frequencies of C allele and C/C genotype were higher in the patients with family history (p = 0.034; p < 0.0001).

CONCLUSIONS

The rs3118470 single nucleotide polymorphism of IL2RA may be a genetic marker to assess the risk of AA in a Chinese population.

The estimated glomerular filtration rate is associated with subclinical atherosclerosis, independently of albuminuria, in patients with type 2 diabetes

AIM

The aim of this paper was to study the relationship between the intima-media thickness (IMT) of the carotid artery and the estimated glomerular filtration rate (eGFR) and albuminuria in the Chinese patients with type 2 diabetes mellitus.

METHODS

As a cross-sectional study, common carotid artery (CCA) IMT as a surrogate marker of cardiovascular disease is adopted. Data were obtained from a study undertaken to evaluate the prevalence of diabetic complications. Body mass measurements, fasting blood measures, urinary albuminuria creatinine ratio and carotid atherosclerotic measurements were investigated. Association of the carotid IMT with albuminuria stage and eGFR was determined by stepwise multivariate regression analysis adjusting for the possible confounders.

RESULTS

1) The mean age of all 721 patients was 65.33±11.32 years and the duration of diabetes was 7.72±6.93 years. 2) The percentage of impaired eGFR (<60 mL/min/1.73 m2) and albuminuria was 4.9% and 41.3% respectively, 37.0% with microalbuminuria and 4.3% with macroalbuminuria. 3) Compared to subjects with normoalbuminuria (28.8%), the percentage of CCA-IMT thickening in subjects with macroalbuminuria (41.9%) and microalbuminuria (43.1%) was higher (P<0.01). Moreover, compared to patients with eGFR ≥90 mL/min/1.73 m2 (28.8%), patients with eGFR ranged from 60 to 89 mL/min/1.73 m2 (43.2%) and eGFR< 60 mL/min/1.73 m2 (51.4%) tended to have greater percentage of CCA-IMT thickening (P<0.01). 4) In a stepwise regression model, age, fasting blood glucose, total cholesterol, reduced HDL-cholesterol and eGFR were independent predictors of CCA-IMT, after adjusting for potential confounders including gender, current smoker, duration of diabetes, waist circumference, hypertension, systolic blood pressure, diastolic blood pressure, triglyceride, LDL-cholesterol, postprandial glucose, HbA1c and albuminuria stage.

CONCLUSION

Reduced eGFR associated with IMT thickening independently of albuminuria is found in the patients with type 2 diabetes mellitus, and further studies investigating the clinical outcomes are needed because this study is based on a cross-sectional design.

Effect of preconditioning with hyperbaric oxygen on neural cell apoptosis after spinal cord injury in rats

AIM

The aim of this study was to study the effect of preconditioning with hyperbaric oxygen on neural cell apoptosis after spinal cord injury in rats at different times, and to study the mechanism of neuroprotection with hyperbaric oxygen preconditioning after spinal cord injury.

METHODS

Fifty-five adult Sprague-Dawley rats were randomly divided into 3 groups, a hyperbaric oxygen preconditioning group (Hoping, N.=25), a normal injury group (NI, N.=25) and a control group (CON, N.=5). The acute spinal cord injury rat models were established using Allen's method, the spinal cord injury selections were obtained separately after injury day 1, 5, 7, 10 and 14, the neural cell apoptosis after the spinal cord injury in the rat was detected by the HE staining and TUNEL method.

RESULTS

The TUNEL-positive apoptotic cells were found in both the hyperbaric oxygen preconditional group and in the normal injury group. However, There was a statistically significant difference between each group (P<0.05). In the hyperbaric oxygen preconditioning group, the number of apoptotic cells decreased, while the neurofunction of the spinal cord was improved compared with the other two groups.

CONCLUSION

HBO preconditioning can reduce the number of apoptotic cells and promote the nerve functional recovery in rats after spinal cord injury, which provide some experimental basis for currently clinical hyperbaric oxygen therapy.

Prospective trial finds nystatin mouthwash effective prophylaxis for pulmonary invasive fungal infections that originate in the throat of patients with hematologic malignancies

We investigated the source of fungi in the lungs of patients with hematological malignancies who had invasive pulmonary fungal infections (IPFI). We also conducted a prospective study to evaluate the efficacy of different mouthwash solutions in preventing IPFI in patients with hematologic malignancies. In order to determine the source of fungi in the lungs of 30 patients with hematologic malignancies who had IPFI, we collected samples from sites with suspected fungal infection and used PCR and sequencing for pathogen identification. For the prospective study, we enrolled 158 patients with hematological malignancies who had IPFI and randomly assigned them to one of three mouthwash groups: 1% nystatin, 2.5% sodium bicarbonate, or normal saline. Fungal staining and incidence of IPFI, oral fungal infection, and intestinal fungal infection were evaluated. We showed that 96.7% of the fungi isolated from the throats and the lungs were identical; 76.9% of the fungi from the lungs and digestive tracts were identical and, 84.6 % of the fungi from the throats and digestive tract were identical. Patients using 1% nystatin had lower incidence of IPFI (1.6%) and fungal enteritis (1.6%) than those using sodium bicarbonate (16.3% and 14.3%) or normal saline (27.7% and 12.8%). All treatments had low incidences of oral fungal infections (0 to 4.3%). Our data showed that fungi originating from mouth and throat cause IPFI. We also showed that use of a prophylactic mouthwash containing 1% nystatin was effective in preventing IPFI in patients with hematological malignancies.

Genome-wide association study in a Chinese population identifies a susceptibility locus for type 2 diabetes at 7q32 near PAX4

AIMS/HYPOTHESIS

Most genetic variants identified for type 2 diabetes have been discovered in European populations. We performed genome-wide association studies (GWAS) in a Chinese population with the aim of identifying novel variants for type 2 diabetes in Asians.

METHODS

We performed a meta-analysis of three GWAS comprising 684 patients with type 2 diabetes and 955 controls of Southern Han Chinese descent. We followed up the top signals in two independent Southern Han Chinese cohorts (totalling 10,383 cases and 6,974 controls), and performed in silico replication in multiple populations.

RESULTS

We identified CDKN2A/B and four novel type 2 diabetes association signals with p < 1 × 10(-5) from the meta-analysis. Thirteen variants within these four loci were followed up in two independent Chinese cohorts, and rs10229583 at 7q32 was found to be associated with type 2 diabetes in a combined analysis of 11,067 cases and 7,929 controls (p meta = 2.6 × 10(-8); OR [95% CI] 1.18 [1.11, 1.25]). In silico replication revealed consistent associations across multiethnic groups, including five East Asian populations (p meta = 2.3 × 10(-10)) and a population of European descent (p = 8.6 × 10(-3)). The rs10229583 risk variant was associated with elevated fasting plasma glucose, impaired beta cell function in controls, and an earlier age at diagnosis for the cases. The novel variant lies within an islet-selective cluster of open regulatory elements. There was significant heterogeneity of effect between Han Chinese and individuals of European descent, Malaysians and Indians.

CONCLUSIONS/INTERPRETATION

Our study identifies rs10229583 near PAX4 as a novel locus for type 2 diabetes in Chinese and other populations and provides new insights into the pathogenesis of type 2 diabetes.

Osteocalcin, glucose metabolism, lipid profile and chronic low-grade inflammation in middle-aged and elderly Chinese

AIM

To assess the relationship between serum total osteocalcin and measurements of adiposity, glucose tolerance, lipid profile, adipokine and chronic low-grade inflammation in middle-aged and elderly Chinese subjects.

METHODS

We performed a cross-sectional community-based study in central Shanghai. Serum total osteocalcin was measured by radioimmunoassay in 783 men and 946 post-menopausal women. Their associations with measurements of adiposity, glucose tolerance, lipid profile and chronic low-grade inflammation were examined.

RESULTS

Serum total osteocalcin levels revealed a sexual dimorphism, with post-menopausal women having significantly higher levels than men (P < 0.001). Serum osteocalcin levels of participants with self-reported cardiovascular disease were significantly lower (P = 0.044) than those without. In men, serum osteocalcin levels of participants with the metabolic syndrome were significantly lower than those without the metabolic syndrome (P = 0.036). Serum osteocalcin correlated negatively with fasting serum insulin, homeostasis model assessment of insulin resistance, alanine aminotransferase, triglycerides and total cholesterol, and positively with homeostasis model assessment of β-cell function in both men and post-menopausal women (all P < 0.05). In men, serum osteocalcin correlated negatively with BMI, diastolic blood pressure, fasting plasma glucose and 2-h oral glucose tolerance test glucose after adjustment for age (all P < 0.05). In post-menopausal women, serum osteocalcin correlated negatively with waist-hip ratio, LDL cholesterol and C-reactive protein, and positively with adiponectin (all P < 0.05). Serum osteocalcin was not associated with CXC chemokine ligand 5 level (P > 0.05). Alanine aminotransferase was an independent predictor of serum osteocalcin in both men and post-menopausal women (both P < 0.001). Adiponectin was an independent predictor of serum osteocalcin in post-menopausal women (P = 0.011). Serum osteocalcin was an independent predictor of homeostasis model assessment of β-cell function in both genders (both P < 0.05).

CONCLUSIONS

Serum total osteocalcin was closely associated with glucose and lipid metabolism in both Chinese men and post-menopausal women.

Risk factors for invasive pulmonary fungal infection in patients with hematological malignancies not receiving hematopoietic stem cell transplant

We investigated the incidence, pathogens and risk factors of invasive pulmonary fungal infection (IPFI) in patients with hematological malignancies who did not receive hematopoietic stem cell transplantation (HSCT). Of the 323 patients included, 106 had confirmed IPFI, 111 had pulmonary bacterial infections, and 106 did not have pulmonary infections. The risk factors for IPFI were explored through logistic univariate and multivariate analysis. The incidence of IPFI in patients with hematological malignancies but without HSCT was 3.5%. The leading pathogen was Candida albicans which accounted for 50.7% of the infections, and the second one was Aspergillus which accounted for 37.3% of the infections. The main risk factors for these patients were days of hospitalization, history of IPFI, agranulocytosis, concomitant hypoproteinemia, number of antibiotics being used, concomitant bacterial sepsis, and age. Furthermore, Nystatin mouthwash was protective against IPFI. Among patients with hematological malignancies, IPFI causes the highest proportion of deaths. We have identified two important pathogens and several risk factors as well as one factor protective against IPFI. Awareness of risk factors and reduction of pathogens can decrease the incidence of IPFI.

Fasting capillary blood glucose: an appropriate measurement in screening for diabetes and pre-diabetes in low-resource rural settings

OBJECTIVE

To evaluate the efficiency of fasting capillary blood glucose (FCG) measurement as compared with fasting venous plasma glucose (FPG) measurement in screening diabetes and pre-diabetes in low-resource rural settings.

SUBJECTS AND METHODS

In 2010, 993 participants were randomly selected from 9 villages in Yunnan province using cluster sampling method. Samples for FCG and FPG test were obtained after demographics and physical examination. The oral glucose tolerance test was performed in parallel as gold standard for diagnosis. Diagnostic capacities of the FCG measurement in predicting undiagnosed diabetes and pre-diabetes were assessed. The performance of FCG and FPG tests was compared.

RESULTS

Fifty-seven individuals with undiagnosed diabetes and 145 subjects with pre-diabetes were detected. The concordance between FCG and FPG levels was high (r = 0.75, p < 0.001). The area under the curve (AUC) for FCG test in predicting diabetes was 0.88 [95% confidence interval (CI) 0.82-0.93] with the optimal cutoff value of 5.65 mmol/l, sensitivity of 84.2%, and specificity of 79.3%. The corresponding values in FPG tests were 0.92 (95% CI 0.88-0.97) (AUC), 6.51 mmol/l (optimal cutoff point), 82.5% (sensitivity) and 98.3% (specificity), respectively. No significant difference was found in the AUC for the two screening strategies.

CONCLUSION

FCG measurement is considered to be a convenient, practicable screening method in low-resource rural communities with acceptable test properties.

Abstract P5-01-03: Discordant Estrogen and Progesterone Receptor Status in Breast Cancer

Introduction: Hormone receptor status is used to guide clinical therapy in breast cancer. Estrogen receptor (ER) assays from pathology reports have been shown to be in agreement with ER measured by a centralized laboratory on tissue microarray 87% of the time (Kappa = 0.64); however, little is known of reproducibility within subsets of patients defined by ER/PR status (1).

Methods: We computed percent agreement and Kappa statistics for ER/PR status as reported in pathology reports from Nurse's Health Study (NHS) participants with breast cancer from 1976 to 2000, and as scored by immunohistochemistry (IHC) on tissue microarrays at a central laboratory (n = 2011). Statistics were computed separately for 4 subsets of patients stratified by ER/PR status as defined by pathology reports (ER+/PR+, ER+/PR−, ER−/PR+, ER−/PR−). We also used a curated compilation of publicly available gene expression data sets providing both IHC and microarray data on ER and PR expression (n = 1236).

Results: We observed significant heterogeneity in Kappa values across the four groups of patients, with ER+/PR+ and ER−/PR- showing the strongest agreement, ER+/PR- showing fair agreement, and ER−/PR+ showing no significant agreement: 89.1% of ER+/PR+ cases from medical record were ER+/PR+ by TMA (κ=.60), 69.4% of ER−/PR- cases from medical record were ER−/PR- by TMA (κ=.63), 42% of ER+/PR- cases from medical record were ER+/PR- by TMA (κ=.37), and only 6% of cases of ER−/PR+ cases from medical record were ER−/PR+ by TMA (κ=.06). Using publicly available microarray data, we observed similar results comparing IHC to gene expression data in the same samples. Expression values were scaled across patients, and a patient was classified as positive for the marker by microarray if the scaled expression value was greater than zero. The agreement between IHC data and gene expression-based classification was 50.0% (k = .50), 80.8% (κ=.54), 42.0% (κ=.15), and 7.2% (κ = −.006) for ER+/PR+, ER−/PR−, ER+/PR−, and ER−/PR+, respectively.

Conclusion: ER−/PR+ is by far the most rare and least reproducible subset of breast cancer cases. Given the lack of reproducibility of the ER−/PR+ group and the minimal reported benefit from hormonal therapy in these patients (2), these data question the clinical utility of assessment of PR, particularly in ER− breast cancer.

1. Collins LC, Marotti JD, Baer HJ, Tamimi RM. Comparison of estrogen receptor results from pathology reports with results from central laboratory testing. Journal of the National Cancer Institute. 2008;100(3):218–21. 2. Anderson H, Hills M, Zabaglo L, A'Hern R, Leary AF, Haynes BP, et al. Relationship between estrogen receptor, progesterone receptor, HER-2 and Ki67 expression and efficacy of aromatase inhibitors in advanced breast cancer. Annals of oncology: official journal of the European Society for Medical Oncology/ESMO. 2011;22(8):1770–6.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P5-01-03.

Rickettsia felis in cat fleas, Ctenocephalides felis parasitizing opossums, San Bernardino County, California

Los Angeles and Orange Counties are known endemic areas for murine typhus in California; however, no recent reports of flea-borne rickettsioses are known from adjacent San Bernardino County. Sixty-five opossums (Didelphis virginiana) were trapped in the suburban residential and industrial zones of the southwestern part of San Bernardino County in 2007. Sixty out of 65 opossums were infested with fleas, primarily cat fleas, Ctenocephalides felis (Bouché, 1835). The flea minimum infection rate with Rickettsia felis was 13.3% in pooled samples and the prevalence was 23.7% in single fleas, with two gltA genotypes detected. In spite of historic records of murine typhus in this area, no evidence for circulation of R. typhi in fleas was found during the present study. Factors contributing to the absence of R. typhi in these cat fleas in contrast to its presence in cat fleas from Orange and Los Angeles Counties are unknown and need to be investigated further in San Bernardino County.

Mean peak systolic velocity of the superior thyroid artery is correlated with radioactive iodine uptake in untreated thyrotoxicosis

OBJECTIVE

To evaluate the correlation between mean superior thyroid artery peak systolic velocity (STA-PSV) and radioactive iodine uptake (RAIU) in Chinese patients with untreated thyrotoxicosis, using retrospectively and prospectively collected data.

METHODS

Patients with untreated thyrotoxicosis (n = 220) and euthyroid control subjects (n = 30) underwent thyroid function, thyroid autoantibody and thyroid ultrasonography tests. Mean STA-PSV was measured by ultrasonography. RAIU tests identified 168 patients with Graves' disease and 52 with destructive thyroiditis. Linear correlation of mean STA-PSV with 3-h and 24-h RAIU, and sensitivity, specificity and receiver operating characteristic (ROC) curves for mean STA-PSV in the differential diagnosis of Graves' disease and destructive thyroiditis were calculated.

RESULTS

Mean STA-PSV was significantly higher in Graves' disease than in destructive thyroiditis. Mean STA-PSV correlated positively and significantly with 3-h and 24-h RAIU. Area under the ROC curve of mean STA-PSV for the differential diagnosis of Graves' disease and destructive thyroiditis was 0.825 (optimum cut-off value of mean STA-PSV, 45.25 cm/s; sensitivity, 80.4%; specificity, 81.4%).

CONCLUSIONS

Detection of mean STA-PSV by ultrasonography agrees with RAIU and is useful for the differential diagnosis of thyrotoxicosis in Chinese patients.

Modification of growth related enzymatic pathways and apparent loss of tumorigenicity of a ras-transformed bovine endothelial cell line by treatment with 5-iodo-6-amino-1,2-benzopyrone (INH2BP)

Bovine aortic endothelial cells were converted to a highly tumorigenic cell line by transfection with Ha-ras and stimulation with thrombin. Sustained pretreatment with a non-cytotoxic concentration (600 mu M) of 5-iodo-6-amino-1,2-benzopyrone (INH2BP), a lipophilic ligand of poly(ADP-ribose) polymerase, abrogated in vivo tumorigenicity, of 10(5) cells per inoculum an effect which developed progressively during 2 to 6 weeks of drug treatment. The initial action of the drug was cytostasis, consisting of an arrest in prophase, extreme cell enlargement consistent with cytoplasmic hypertrophy, as seen by EM, and dramatic morphologic changes. Although neither DNA, RNA or protein syntheses are directly affected by INH2BP, apparently newly synthesized cellular DNA is degraded by endonucleases, which are upregulated by the inhibition of their poly-ADP-ribosylation. The drug treated cells exhibited greatly increased respiration and aerobic glycolysis, due to an augmentation of,glycolytic and respiratory enzymes in enlarged cells. These responses to the drug were reversible in cell cultures following drug removal, within 5-10 days drug exposure but the progressive loss of tumorigenicity in nude mice that developed after 3-6 weeks of drug exposure of cells, prior to inoculation to nude mice, was not reversible in vivo. Drug treatment produced a sustained 70-80% inhibition of pADPRT in intact cells at 600 mu M extracellular concentration of INH2BP. The prerequisite for the abrogation of tumorigenicity was the maintenance of pADPRT inhibition. The arrest of cell multiplication and a large decrease of Topo I, especially of Topo II and MAP kinase activities occurred without loss of enzyme protein as assayed in cell extracts of drug-treated cells. However INH2BP had no direct effect on these enzymes. Drug treatment down-regulated DNA-methyltransferase, PKC, ODC proteins, diminished cyclin A protein, but the hypophosphorylated form of Rb protein was significantly augmented. None of the enzymatic components of signal pathways so far studied, were directly affected by INH2BP. The inhibition of pADPRT by INH2BP coincided with an induction or activation of alkaline phosphatase and leucyl and glutamyl peptidase. The pADPRT content or the expression of pADPRT gene were not influenced by drug treatment, but the expression of ras gene was completely absent in nontumorigenic drug-treated cells, without a loss of ras gene from genomic DNA. Telomerase activity was not directly influenced by INH2BP treatment when assayed in diluted cell extracts, but the addition of homogeneous pADPRT to cell extracts, to approach physiological concentration of this protein in the cell, inhibited telomerase activity by binding of the polymer-free pADPRT to telomer templates. We conclude that inhibition of pADPRT indirectly down-regulates growth stimulatory signal pathways and sustains growth-arrested cells in culture at a pre-apoptotic threshold which explains the absence of tumorigenicity in vivo.

A framework genetic map of Muscadinia rotundifolia

This study presents a framework linkage map based on microsatellite markers for Muscadinia rotundifolia (1n = 20). The mapping population consisted of 206 progeny generated from a cross of two M. rotundifolia varieties, 'Fry' and 'Trayshed'. A total of 884 primers were tested for their ability to amplify markers: 686 amplified and 312 simple sequence repeat (SSR) primer pairs generated 322 polymorphic markers for either one or both parents. The map for the female parent 'Fry' consisted of 212 markers and covered 879 cM on 18 chromosomes. The average distance between the markers was 4.1 cM and chromosome 6 was not represented due to a lack of polymorphic markers. The map for the male parent 'Trayshed' consisted of 191 markers and covered 841 cM on 19 chromosomes. The consensus map consisted of 314 markers on 19 chromosomes with a total distance of 1,088 cM, which represented 66 % of the distance covered by the Vitis vinifera reference linkage map. Marker density varied greatly among chromosomes from 5 to 35 mapped markers. Relatively good synteny was observed across 19 chromosomes based on markers in common with the V. vinifera reference map. Extreme segregation distortion was observed for chromosome 8 and 14 on the female parent map, and 4 on the male parent map. The lack of mapping coverage for the 20th M. rotundifolia chromosome is discussed in relation to possible evolutionary events that led to the reduction in chromosome number from 21 to 19 in the ancestral genome.

From incommensurate correlations to mesoscopic spin resonance in YbRh2Si2

Spin fluctuations are reported near the magnetic field-driven quantum critical point in YbRh(2)Si(2). On cooling, ferromagnetic fluctuations evolve into incommensurate correlations located at q(0) = ±(δ,δ), with δ = 0.14 ± 0.04 r.l.u. At low temperatures, an in-plane magnetic field induces a sharp intradoublet resonant excitation at an energy E(0) = gμ(B)μ(0)H with g = 3.8 ± 0.2. The intensity is localized at the zone center, indicating precession of spin density extending ξ = 6 ± 2 Å beyond the 4f site.

Laboratory studies on surface sampling of Bacillus anthracis contamination: summary, gaps and recommendations

This article summarizes previous laboratory studies to characterize the performance of methods for collecting, storing/transporting, processing and analysing samples from surfaces contaminated by Bacillus anthracis or related surrogates. The focus is on plate culture and count estimates of surface contamination for swab, wipe and vacuum samples of porous and nonporous surfaces. Summaries of the previous studies and their results were assessed to identify gaps in information needed as inputs to calculate key parameters critical to risk management in biothreat incidents. One key parameter is the number of samples needed to make characterization or clearance decisions with specified statistical confidence. Other key parameters include the ability to calculate, following contamination incidents, the (i) estimates of B. anthracis contamination, as well as the bias and uncertainties in the estimates and (ii) confidence in characterization and clearance decisions for contaminated or decontaminated buildings. Gaps in knowledge and understanding identified during the summary of the studies are discussed. Additional work is needed to quantify (i) the false-negative rates of surface-sampling methods with lower concentrations on various surfaces and (ii) the effects on performance characteristics of: aerosol vs liquid deposition of spores, using surrogates instead of B. anthracis, real-world vs laboratory conditions and storage and transportation conditions. Recommendations are given for future evaluations of data from existing studies and possible new studies.

Learning Chronobiology by Improving Wikipedia

Although chronobiology is of growing interest to scientists, physicians, and the general public, access to recent discoveries and historical perspectives is limited. Wikipedia is an online, user-written encyclopedia that could enhance public access to current understanding in chronobiology. However, Wikipedia is lacking important information and is not universally trusted. Here, 46 students in a university course edited Wikipedia to enhance public access to important discoveries in chronobiology. Students worked for an average of 9 h each to evaluate the primary literature and available Wikipedia information, nominated sites for editing, and, after voting, edited the 15 Wikipedia pages they determined to be highest priorities. This assignment ( http://www.nslc.wustl.edu/courses/Bio4030/wikipedia_project.html ) was easy to implement, required relatively short time commitments from the professor and students, and had measurable impacts on Wikipedia and the students. Students created 3 new Wikipedia sites, edited 12 additional sites, and cited 347 peer-reviewed articles. The targeted sites all became top hits in online search engines. Because their writing was and will be read by a worldwide audience, students found the experience rewarding. Students reported significantly increased comfort with reading, critiquing, and summarizing primary literature and benefited from seeing their work edited by other scientists and editors of Wikipedia. We conclude that, in a short project, students can assist in making chronobiology widely accessible and learn from the editorial process.

Association of genetic variation in FTO with risk of obesity and type 2 diabetes with data from 96,551 East and South Asians

AIMS/HYPOTHESIS

FTO harbours the strongest known obesity-susceptibility locus in Europeans. While there is growing evidence for a role for FTO in obesity risk in Asians, its association with type 2 diabetes, independently of BMI, remains inconsistent. To test whether there is an association of the FTO locus with obesity and type 2 diabetes, we conducted a meta-analysis of 32 populations including 96,551 East and South Asians.

METHODS

All studies published on the association between FTO-rs9939609 (or proxy [r (2) > 0.98]) and BMI, obesity or type 2 diabetes in East or South Asians were invited. Each study group analysed their data according to a standardised analysis plan. Association with type 2 diabetes was also adjusted for BMI. Random-effects meta-analyses were performed to pool all effect sizes.

RESULTS

The FTO-rs9939609 minor allele increased risk of obesity by 1.25-fold/allele (p = 9.0 × 10(-19)), overweight by 1.13-fold/allele (p = 1.0 × 10(-11)) and type 2 diabetes by 1.15-fold/allele (p = 5.5 × 10(-8)). The association with type 2 diabetes was attenuated after adjustment for BMI (OR 1.10-fold/allele, p = 6.6 × 10(-5)). The FTO-rs9939609 minor allele increased BMI by 0.26 kg/m(2) per allele (p = 2.8 × 10(-17)), WHR by 0.003/allele (p = 1.2 × 10(-6)), and body fat percentage by 0.31%/allele (p = 0.0005). Associations were similar using dominant models. While the minor allele is less common in East Asians (12-20%) than South Asians (30-33%), the effect of FTO variation on obesity-related traits and type 2 diabetes was similar in the two populations.

CONCLUSIONS/INTERPRETATION

FTO is associated with increased risk of obesity and type 2 diabetes, with effect sizes similar in East and South Asians and similar to those observed in Europeans. Furthermore, FTO is also associated with type 2 diabetes independently of BMI.

Separating the chaff from the grain (Tularemia)

A case of ulcero-glandular tularemia is presented. Discussion is based on the differential diagnosis of a patient presenting with cutaneous lesions, regional lymphadenopathy and fever.

Metabolic effects of bariatric surgery in type 2 diabetic patients with body mass index < 35 kg/m2

AIM

The aim of this meta-analysis is to assess the metabolic effects of bariatric surgery in type 2 diabetes mellitus (T2DM) patients with body mass index (BMI) < 35 kg/m(2) .

METHODS

We performed an electronic literature search of published articles to identify relevant evidence since inception to June 2011. Primary outcome measures were metabolic improvement and resolution diabetes after bariatric surgery. The weighted mean difference (WMD) and its 95% confidence interval (CI) were calculated from the raw data extracted from the original literature. The software Review Manager (version 4.3.1) was applied for meta-analysis.

RESULTS

Thirteen trials involving 357 patients were included in the meta-analysis. The follow-up interval ranged from 6 months to 18 years. According to WMD calculation, bariatric surgery led to 5.18 kg/m(2) of BMI lowering (95% CI, 3.79-6.57, p < 0.00001), 4.8 mmol/l of fasting plasma glucose (FPG) decrement (95% CI, 3.88-5.71 mmol/l, p < 0.00001), 2.59% of HbA1c decreasing (95% CI, 2.12-3.07%, p < 0.00001), 56.67 mg/dl of triglyceride decrement (95% CI 11.53-101.82, p = 0.01) and 48.38 mg/dl of total cholesterol reduction (95% CI 21.08-75.68, p = 0.0005). Moreover, the procedures produced an increased high-density lipoprotein cholesterol by 5.37 mg/dl (95% CI -11.37-0.63, p = 0.08). However, this effect was not statistically significant. Overall, 80.0% of the patients achieved adequate glycaemic control (HbA1c < 7%) without antidiabetic medication. The surgeries produced a low incidence of major complications (3.2%) with no mortality.

CONCLUSIONS

Bariatric surgery is effectual and safe in the treatment of non-severely obese (BMI < 35 kg/m(2) ) T2DM patients. Moreover, the metabolic benefits acquired from the procedures can be long sustained after the surgery.

Metabolic effects of bariatric surgery in type 2 diabetic patients with body mass index < 35 kg/m2

AIM

The aim of this meta-analysis is to assess the metabolic effects of bariatric surgery in type 2 diabetes mellitus (T2DM) patients with body mass index (BMI) < 35 kg/m(2) .

METHODS

We performed an electronic literature search of published articles to identify relevant evidence since inception to June 2011. Primary outcome measures were metabolic improvement and resolution diabetes after bariatric surgery. The weighted mean difference (WMD) and its 95% confidence interval (CI) were calculated from the raw data extracted from the original literature. The software Review Manager (version 4.3.1) was applied for meta-analysis.

RESULTS

Thirteen trials involving 357 patients were included in the meta-analysis. The follow-up interval ranged from 6 months to 18 years. According to WMD calculation, bariatric surgery led to 5.18 kg/m(2) of BMI lowering (95% CI, 3.79-6.57, p < 0.00001), 4.8 mmol/l of fasting plasma glucose (FPG) decrement (95% CI, 3.88-5.71 mmol/l, p < 0.00001), 2.59% of HbA1c decreasing (95% CI, 2.12-3.07%, p < 0.00001), 56.67 mg/dl of triglyceride decrement (95% CI 11.53-101.82, p = 0.01) and 48.38 mg/dl of total cholesterol reduction (95% CI 21.08-75.68, p = 0.0005). Moreover, the procedures produced an increased high-density lipoprotein cholesterol by 5.37 mg/dl (95% CI -11.37-0.63, p = 0.08). However, this effect was not statistically significant. Overall, 80.0% of the patients achieved adequate glycaemic control (HbA1c < 7%) without antidiabetic medication. The surgeries produced a low incidence of major complications (3.2%) with no mortality.

CONCLUSIONS

Bariatric surgery is effectual and safe in the treatment of non-severely obese (BMI < 35 kg/m(2) ) T2DM patients. Moreover, the metabolic benefits acquired from the procedures can be long sustained after the surgery.