Previous fracture and subsequent fracture risk: a meta-analysis to update FRAX

A large international meta-analysis using primary data from 64 cohorts has quantified the increased risk of fracture associated with a previous history of fracture for future use in FRAX.

INTRODUCTION

The aim of this study was to quantify the fracture risk associated with a prior fracture on an international basis and to explore the relationship of this risk with age, sex, time since baseline and bone mineral density (BMD).

METHODS

We studied 665,971 men and 1,438,535 women from 64 cohorts in 32 countries followed for a total of 19.5 million person-years. The effect of a prior history of fracture on the risk of any clinical fracture, any osteoporotic fracture, major osteoporotic fracture, and hip fracture alone was examined using an extended Poisson model in each cohort. Covariates examined were age, sex, BMD, and duration of follow-up. The results of the different studies were merged by using the weighted β-coefficients.

RESULTS

A previous fracture history, compared with individuals without a prior fracture, was associated with a significantly increased risk of any clinical fracture (hazard ratio, HR = 1.88; 95% CI = 1.72-2.07). The risk ratio was similar for the outcome of osteoporotic fracture (HR = 1.87; 95% CI = 1.69-2.07), major osteoporotic fracture (HR = 1.83; 95% CI = 1.63-2.06), or for hip fracture (HR = 1.82; 95% CI = 1.62-2.06). There was no significant difference in risk ratio between men and women. Subsequent fracture risk was marginally downward adjusted when account was taken of BMD. Low BMD explained a minority of the risk for any clinical fracture (14%), osteoporotic fracture (17%), and for hip fracture (33%). The risk ratio for all fracture outcomes related to prior fracture decreased significantly with adjustment for age and time since baseline examination.

CONCLUSION

A previous history of fracture confers an increased risk of fracture of substantial importance beyond that explained by BMD. The effect is similar in men and women. Its quantitation on an international basis permits the more accurate use of this risk factor in case finding strategies.

The effect of Mediterranean diet on inflammatory biomarkers and components of metabolic syndrome in adolescent girls

BACKGROUND

The prevalence of obesity and metabolic syndrome (MetS) during childhood and adolescence is rising significantly worldwide. Previous studies have shown that following a healthy dietary pattern, like the Mediterranean diet (MD), might be an efficacious approach for the prevention and management of MetS during childhood. In the present study, we aimed to examine the effect of MD on inflammatory markers and components of MetS among adolescent girls with MetS.

METHODS

This randomized controlled clinical trial was conducted on 70 girl adolescents with metabolic syndrome. Patients in the intervention group followed a prescribed MD, while participants in the control group received dietary advice according to the food pyramid. The length of intervention was 12 weeks. Participants' dietary intakes were evaluated using three 1-day food records throughout the study. Anthropometric measures, inflammatory markers, systolic and diastolic blood pressure, and hematological factors were assessed at the baseline and end of the trial. An intention-to-treat approach was taken into account for the statistical analysis.

RESULTS

After 12 weeks, participants in the intervention group had lower weight (Ptime*group ≤ 0/001), body mass index (BMI) (Ptime*group ≤ 0/001), and waist circumference (WC) (Ptime*group ≤ 0/001) compared with those in the control group. In addition, MD resulted in a significantly reduced systolic blood pressure compared to the those in the control group (Ptime*group ≤ 0/001). In terms of metabolic variables, MD led to a significant decrease in fasting blood glucose (FBS) (Ptime*group ≤ 0/001), triglycerides (TG) (Ptime*group ≤ 0/001), low-density lipoprotein (LDL) (Ptime*group ≤ 0/001), homeostatic model assessment of insulin resistance (HOMA-IR) (Ptime*group = 0/02) and a meaningful increase in serum levels of high-density lipoprotein (HDL) (Ptime*group ≤ 0/001). In addition, adherence to the MD resulted in a significant reduction in serum levels of inflammatory markers including Interleukin 6 (IL-6) (Ptime*group = 0/02) and high-sensitivity C-reactive protein (hs-CRP) (Ptime*group = 0/02). However, no significant effect was seen on serum levels of tumor necrosis factor α (TNF-α) (Ptime*group = 0/43).

CONCLUSION

Overall, the findings of the present study revealed that consumption of MD for 12 weeks resulted in a favorable effect on anthropometric measures, components of MetS, as well as on some inflammatory biomarkers.

Alteration in Gut Microbiota Composition of Older Adults Is Associated with Obesity and Its Indices: A Systematic Review

BACKGROUND

Obesity in the older adults is a health concern that increases the risk of several life-threatening diseases. Previous research has been revealed that alterations in the gut microbiota composition is related to obesity. So, understanding the gut microbiota changes in older adults' obesity may help to provide promising strategies for their health management.

OBJECTIVES

Here we conducted a systematic review that investigate the alteration of gut microbiota composition in association with obesity and its indices in the older adults.

DESIGN

Systematic review.

SETTING

A comprehensive systematic search was performed through PubMed, Web of Science, Scopus and Embase databases for all relative studies up to 2023 with the main search concepts as Microbiota, Obesity and Elderly. The data about gut microbiota in association with obesity indices had been extracted.

PARTICIPANTS

Older adults (≥60 years).

INTERVENTION

None.

MEASUREMENTS

None.

RESULTS

Within 10741 recordes, 11 studies met the inclusion criteria and were included in this systematic review. Most of them indicated the gut microbiota alterations in obese compared with non-obese older adults. However, the gut microbiome composition in obese older adults is affected by other underlying diseases like diabetes and metabolic syndrome. The most important taxa that had abundance alteration in association with obesity in older adults were Christensenellaceae, Porphyromonadaceae and Rikenellaceae, Akkermansia, Blautia, Prevotella, Ruminococcus, Bacteroides and Faecalibacterium.

CONCLUSION

The gut microbiota composition is associated with obesity in older adults. Considering the other factors affecting the composition of gut microbiota, such as age, underlying diseases and lifestyle, a more accurate conclusion about this matter requires more future studies.

Update of the fracture risk prediction tool FRAX: a systematic review of potential cohorts and analysis plan

We describe the collection of cohorts together with the analysis plan for an update of the fracture risk prediction tool FRAX with respect to current and novel risk factors. The resource comprises 2,138,428 participants with a follow-up of approximately 20 million person-years and 116,117 documented incident major osteoporotic fractures.

INTRODUCTION

The availability of the fracture risk assessment tool FRAX® has substantially enhanced the targeting of treatment to those at high risk of fracture with FRAX now incorporated into more than 100 clinical osteoporosis guidelines worldwide. The aim of this study is to determine whether the current algorithms can be further optimised with respect to current and novel risk factors.

METHODS

A computerised literature search was performed in PubMed from inception until May 17, 2019, to identify eligible cohorts for updating the FRAX coefficients. Additionally, we searched the abstracts of conference proceedings of the American Society for Bone and Mineral Research, European Calcified Tissue Society and World Congress of Osteoporosis. Prospective cohort studies with data on baseline clinical risk factors and incident fractures were eligible.

RESULTS

Of the 836 records retrieved, 53 were selected for full-text assessment after screening on title and abstract. Twelve cohorts were deemed eligible and of these, 4 novel cohorts were identified. These cohorts, together with 60 previously identified cohorts, will provide the resource for constructing an updated version of FRAX comprising 2,138,428 participants with a follow-up of approximately 20 million person-years and 116,117 documented incident major osteoporotic fractures. For each known and candidate risk factor, multivariate hazard functions for hip fracture, major osteoporotic fracture and death will be tested using extended Poisson regression. Sex- and/or ethnicity-specific differences in the weights of the risk factors will be investigated. After meta-analyses of the cohort-specific beta coefficients for each risk factor, models comprising 10-year probability of hip and major osteoporotic fracture, with or without femoral neck bone mineral density, will be computed.

CONCLUSIONS

These assembled cohorts and described models will provide the framework for an updated FRAX tool enabling enhanced assessment of fracture risk (PROSPERO (CRD42021227266)).

The Fusion of Quantitative Molecular Proteomics and Immune-Oncology: A Step Towards Precision Medicine in Cancer Therapeutics

Innate and adaptive immune systems are built-in homeostatic functions of many multicellular organisms and protect the host against foreign pathogens and infections. Dysregulation of the molecular mechanisms of the immune system can result in autoimmune diseases. The immune system can also be harnessed and manipulated to provide targeted cancer therapies, some of them relying on the blockade of immune-checkpoint receptors. Two prominent immune checkpoints, PD-1/PD-L1 and CTLA-4/CD80, comprise receptor-ligand pairs that prevent the host immune cells from attacking host tissues. However, cancer cells upregulate the respective PD-L1 and CD80 ligands for PD-1 and CTLA-4 and thereby evade the host-immune response. Therapeutic drugs that block PD-1/PD-L1 and CTLA-4/CD80 interactions re-enable the immune system to attack cancer cells, but their prognostic biomarker remains challenging. In this review, we discuss how the use of quantitative molecular imaging can be exploited to predict the response to anti-PD-1/PD-L1 therapies and to identify cancer patients who would benefit from them.

Abstract 2337: Label-free single-cell drug response determined by fluorescence lifetime imaging microscopy (FLIM) and RNA sequencing

Colorectal cancer (CRC) is the second-leading cause of cancer-related death worldwide, and treatment failure in patients with metastatic CRC portends a poor prognosis. Early detection of chemoresistance would help reduce the usage of ineffective and possibly toxic therapies and facilitate alternative treatment strategies. We present a new technique combining phasor-fluorescence lifetime imaging microscopy (phasor-FLIM) and a machine learning algorithm that quantitatively identifies chemoresistant single cells, which may also be potentially applicable for evaluating heterogeneous circulating tumor cells (CTCs) obtained by liquid biopsy. We used parental HCT116 CRC cells sensitive to 5-fluorouracil (5-FU), a common chemotherapeutic agent used in CRC, to generate a cell line resistant to 5-FU; we confirmed resistance by a cell proliferation assay (MTS). We then analyzed phasor-FLIM patterns in sensitive and resistant cells before and after treatment with 5-FU of two endogenously fluorescent biomarkers, NADH and NADPH, which are key co-enzymes involved in energy metabolism. This was performed at 21% and 1% oxygen, which simulates both standard cell culture and tumor hypoxic conditions. Differences in phasor-FLIM signatures were found in resistant cells that suggested upregulation of the electron transport chain under normoxia (21% oxygen) and reprogrammed glucose metabolism under hypoxia (1% oxygen). Such changes were confirmed using NADH, lactate, and pyruvate production colorimetric tests, which are readouts of energy metabolism. To improve the quantification of changes in phasor-FLIM patterns, a new drug resistance indexing algorithm was developed to separate sensitive and resistant cells based on fluorescence lifetime multiparametric analysis of the intrinsic fluorescent biomarkers at the single-cell level. We then used single-cell total RNA sequencing (scRNA-Seq) to explore gene expression differences between sensitive and resistant HCT116 cells. Principal component analysis (PCA) and Uniform Manifold Approximation and Projection (UMAP) clustering showed a clear separation of 5-FU-sensitive and -resistant cells. There was increased expression of proliferation markers in resistant cells and upregulation of genes involved in electron transport from NADPH to ferredoxin, consistent with our single-cell phasor-FLIM findings. We demonstrate proof of concept that the phasor-FLIM method combined with our new drug resistance indexing algorithm provides a marker-free technology for quantitatively assaying drug response and discriminating drug resistance at single-cell resolution.

Citation Format: Ning Ma, Hui Ren, Naveen Ramalingam, David King, Banafshé Larijani, Stefanie S. Jeffrey. Label-free single-cell drug response determined by fluorescence lifetime imaging microscopy (FLIM) and RNA sequencing [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2337.

Metabolomic biomarkers of low BMD: a systematic review

Due to the metabolic nature of osteoporosis, this study was conducted to identify metabolomic studies investigating the metabolic profile of low bone mineral density (BMD) and osteoporosis. A comprehensive systematic literature search was conducted through PubMed, Web of Science, Scopus, and Embase databases up to April 08, 2020, to identify observational studies with cross-sectional or case-control designs investigating the metabolic profile of low BMD in adults using biofluid specimen via metabolomic platform. The quality assessment panel specified for the "omics"-based diagnostic research (QUADOMICS) tool was used to estimate the methodologic quality of the included studies. Ten untargeted and one targeted approach metabolomic studies investigating biomarkers in different biofluids through mass spectrometry or nuclear magnetic resonance platforms were included in the systematic review. Some metabolite panels, rather than individual metabolites, showed promising results in differentiating low BMD from normal. Candidate metabolites were of different categories including amino acids, followed by lipids and carbohydrates. Besides, certain pathways were suggested by some of the studies to be involved. This systematic review suggested that metabolic profiling could improve the diagnosis of low BMD. Despite valuable findings attained from each of these studies, there was great heterogeneity regarding the ethnicity and age of participants, samples, and the metabolomic platform. Further longitudinal studies are needed to validate the results and confirm the predictive role of metabolic profile on low BMD and fracture. It is also mandatory to address and minimize the heterogeneity in future studies by using reliable quantitative methods. Summary: Due to the metabolic nature of osteoporosis, researchers have considered metabolomic studies recently. This systematic review showed that metabolic profiling including different categories of metabolites could improve the diagnosis of low BMD. However, great heterogeneity was observed and it is mandatory to address and minimize the heterogeneity in future studies.

The enigma of phosphoinositides and their derivatives: Their role in regulation of subcellular compartment morphology

The general segregation of a molecular class, lipids, from the pathways of cellular communication, via endo-membranes, has resulted in the over-simplification and misconceptions in deciphering cell signalling mechanisms. Mechanisms in signal transduction and protein activation require targeting of proteins to membranous compartments with a specific localised morphology and dynamics that are dependent on their lipid composition. Many posttranslational events define cellular behaviours and without the active role of membranous compartments these events lead to various dysregulations of the signalling pathways. We summarise the key findings, using tools such as the rapalogue dimerisation, in the structural roles and signalling of the inter-related phosphoinositide lipids and their derivative, diacylglycerol, in the regulation of nuclear envelope biogenesis and other subcellular compartments such as the nucleoplasmic reticulum.

Effects of metabolic syndrome on bone health in older adults: the Bushehr Elderly Health (BEH) program

Based on the clinical, BMD, and TBS data of 2380 participants aged ≥ 60 which was gathered during the BEH program, stage II, we showed that MetS was positively associated with BMD, while a negative or no association was observed between MetS and TBS depending on the sex and the adjustment model.

INTRODUCTION

The results of previous reports in regard to the effect of metabolic syndrome (MetS) on bone health are not conclusive. This study aimed to evaluate the association between MetS with bone mineral density (BMD) and trabecular bone score (TBS) as an indicator of bone quantity and quality, respectively.

METHODS

Using a cross-sectional design, this study was carried out based on the data collected during the BEH Program, stage II. MetS was defined according to NCEP-ATP III criteria. BMD (at the lumbar spine and the hip) and lumbar spine TBS were assessed by dual-energy X-ray absorptiometry device.

RESULTS

The data of 2380 participants (women = 1228, men = 1152) aged ≥ 60 were analyzed. In the fully adjusted regression models (including BMI), significant associations between MetS and mean BMD were observed across all locations in men (P values ≤ 0.001) and in the lumbar spine in women (P value = 0.003). In addition, the prevalence of osteoporosis (based on BMD) was significantly lower in those with MetS than those without MetS in both sexes, even after full adjustments (women, OR = 0.707, P value = 0.013; men, OR = 0.563, P value = 0.001). In contrast, in age-adjusted regression analyses, the prevalence of degraded bone microarchitecture (TBS ≤ 1.2) was significantly increased in those with MetS than those without, irrespective of the participants' sex (P values < 0.05). The mean TBS was also negatively associated with MetS in women (β = - 0.075, P value = 0.007) but not in men (β = - 0.052, P value = 0.077), in age-adjusted regression models. However, after including BMI in the adjusted models, all significant associations between TBS values and MetS disappeared.

CONCLUSION

It seems that a positive association exists between MetS and BMD, while MetS is either not associated or negatively correlated with bone quality as measured by TBS.

High PD-1/PD-L1 Checkpoint Interaction Infers Tumor Selection and Therapeutic Sensitivity to Anti-PD-1/PD-L1 Treatment

Many cancers are termed immunoevasive due to expression of immunomodulatory ligands. Programmed death ligand-1 (PD-L1) and cluster of differentiation 80/86 (CD80/86) interact with their receptors, programmed death receptor-1 (PD-1) and cytotoxic T-lymphocyte antigen-4 (CTLA-4), respectively, on tumor-infiltrating leukocytes eliciting immunosuppression. Immunotherapies aimed at blocking these interactions are revolutionizing cancer treatments, albeit in an inadequately described patient subset. To address the issue of patient stratification for immune checkpoint intervention, we quantitatively imaged PD-1/PD-L1 interactions in tumor samples from patients, employing an assay that readily detects these intercellular protein-protein interactions in the less than or equal to 10 nm range. These analyses across multiple patient cohorts demonstrated the intercancer, interpatient, and intratumoral heterogeneity of interacting immune checkpoints. The PD-1/PD-L1 interaction was not correlated with clinical PD-L1 expression scores in malignant melanoma. Crucially, among anti-PD-1-treated patients with metastatic non-small cell lung cancer, those with lower PD-1/PD-L1 interaction had significantly worsened survival. It is surmised that within tumors selecting for an elevated level of PD-1/PD-L1 interaction, there is a greater dependence on this pathway for immune evasion and hence, they exhibit more impressive patient response to intervention. SIGNIFICANCE: Quantitation of immune checkpoint interaction by direct imaging demonstrates that immunotherapy-treated patients with metastatic NSCLC with a low extent of PD-1/PD-L1 interaction show significantly worse outcome.

The unprecedented membrane deformation of the human nuclear envelope, in a magnetic field, indicates formation of nuclear membrane invaginations

Human nuclear membrane (hNM) invaginations are thought to be crucial in fusion, fission and remodeling of cells and present in many human diseases. There is however little knowledge, if any, about their lipid composition and dynamics. We therefore isolated nuclear envelope lipids from human kidney cells, analyzed their composition and determined the membrane dynamics after resuspension in buffer. The hNM lipid extract was composed of a complex mixture of phospholipids, with high amounts of phosphatidylcholines, phosphatidylinositols (PI) and cholesterol. hNM dynamics was determined by solid-state NMR and revealed that the lamellar gel-to-fluid phase transition occurs below 0 °C, reflecting the presence of elevated amounts of unsaturated fatty acid chains. Fluidity was higher than the plasma membrane, illustrating the dual action of Cholesterol (ordering) and PI lipids (disordering). The most striking result was the large magnetic field-induced membrane deformation allowing to determine the membrane bending elasticity, a property related to hydrodynamics of cells and organelles. Human Nuclear Lipid Membranes were at least two orders of magnitude more elastic than the classical plasma membrane suggesting a physical explanation for the formation of nuclear membrane invaginations.

FRAX-based intervention and assessment thresholds for osteoporosis in Iran

We compared the utility of the current Iranian guidelines that recommend treatment in women with a T-score ≤ - 2.5 SD with a FRAX-based intervention threshold equivalent to women of average BMI with a prior fragility fracture. Whereas the FRAX-based intervention threshold identified women at high fracture probability, the T-score threshold was less sensitive, and the associated fracture risk decreased markedly with age.

INTRODUCTION

The fracture risk assessment algorithm FRAX® has been recently calibrated for Iran, but guidance is needed on how to apply fracture probabilities to clinical practice.

METHODS

The age-specific ten-year probabilities of a major osteoporotic fracture were calculated in women with average BMI to determine fracture probabilities at two potential intervention thresholds. The first comprised the age-specific fracture probabilities associated with a femoral neck T-score of - 2.5 SD, in line with current guidelines in Iran. The second approach determined age-specific fracture probabilities that were equivalent to a woman with a prior fragility fracture, without BMD. The parsimonious use of BMD was additionally explored by the computation of upper and lower assessment thresholds for BMD testing.

RESULTS

When a BMD T-score ≤ - 2.5 SD was used as an intervention threshold, FRAX probabilities in women aged 50 years was approximately two-fold higher than in women of the same age but with an average BMD and no risk factors. The relative increase in risk associated with the BMD threshold decreased progressively with age such that, at the age of 80 years or more, a T-score of - 2.5 SD was actually protective. The 10-year probability of a major osteoporotic fracture by age, equivalent to women with a previous fracture rose with age from 4.9% at the age of 50 years to 17%, at the age of 80 years, and identified women at increased risk at all ages.

CONCLUSION

Intervention thresholds based on BMD alone do not effectively target women at high fracture risk, particularly in the elderly. In contrast, intervention thresholds based on fracture probabilities equivalent to a "fracture threshold" target women at high fracture risk.

A Complex Interplay of Anionic Phospholipid Binding Regulates 3'-Phosphoinositide-Dependent-Kinase-1 Homodimer Activation

3'-Phosphoinositide-dependent-Kinase-1 (PDK1) is a master regulator whereby its PI3-kinase-dependent dysregulation in human pathologies is well documented. Understanding the direct role for PtdIns(3,4,5)P3 and other anionic phospholipids in the regulation of PDK1 conformational dynamics and its downstream activation remains incomplete. Using advanced quantitative-time-resolved imaging (Fluorescence Lifetime Imaging and Fluorescence Correlation Spectroscopy) and molecular modelling, we show an interplay of antagonistic binding effects of PtdIns(3,4,5)P3 and other anionic phospholipids, regulating activated PDK1 homodimers. We demonstrate that phosphatidylserine maintains PDK1 in an inactive conformation. The dysregulation of the PI3K pathway affects the spatio-temporal and conformational dynamics of PDK1 and the activation of its downstream substrates. We have established a new anionic-phospholipid-dependent model for PDK1 regulation, depicting the conformational dynamics of multiple homodimer states. We show that the dysregulation of the PI3K pathway perturbs equilibrium between the PDK1 homodimer conformations. Our findings provide a role for the PtdSer binding site and its previously unrewarding role in PDK1 downregulation, suggesting a possible therapeutic strategy where the constitutively active dimer conformer of PDK1 may be rendered inactive by small molecules that drive it to its PtdSer-bound conformer.

Metformin use and risk of fracture: a systematic review and meta-analysis of observational studies

INTRODUCTION

No study is available summarizing earlier publications on the association between metformin use and risk of fracture. This systematic review and meta-analysis were conducted to summarize earlier findings on the association between metformin use and risk of fracture.

METHODS

We conducted a systematic search on all published articles up to October 2018 using online databases including PubMed/Medline, ISI Web of Science, and Scopus. Observational studies that considered metformin use as the exposure variable and bone fracture as the main outcome variable or as one of the outcome variables and participants included were 18 years and older were included in the systematic review. Publications in which hazard ratios (HRs), rate or risk ratios (RRs), or odds ratios (ORs) were reported as effect size were included in the meta-analysis.

RESULTS

Totally, three cohort studies, one cross-sectional study, one nested case-control study, and one case-control study were included in this systematic review and meta-analysis. When seven effect sizes from six studies were combined, a significant inverse association between metformin use and risk of fracture was observed (RR 0.82; 95% CI 0.72, 0.93). No significant between-study heterogeneity was found (I² = 22.4%, P_{heterogeneity} = 0.25). In addition, no evidence of publication bias was seen using Egger's test (P = 0.99).

CONCLUSION

We found that metformin use was inversely associated with the risk of fracture.

Palladium-Catalyzed Regioselective Heck–Suzuki–Miyaura Cascade Cyclization for the Synthesis of Trisubstituted Arylideneisoquinolinones

An Ugi four-component reaction was used to construct propargylamide starting materials for a subsequent domino Heck–Suzuki–Miyaura cross-coupling reaction to give derivatives of 4-benzylidene-1-oxo-3,4-dihydro-1H-isoquinoline.

Resveratrol supplementation significantly influences obesity measures: a systematic review and dose-response meta-analysis of randomized controlled trials

This study aimed to summarize earlier randomized controlled trials on the effects of resveratrol supplementation on body weight (BW), body mass index (BMI), waist circumference (WC) and fat mass (FM). We searched PubMed, SCOPUS, Cochrane Library and Google Scholar from inception to April 2018 using relevant keywords. All clinical trials investigating the effects of resveratrol supplementation on BW, BMI, WC and FM in adults were included. Overall, 28 trials were included. Pooled effect sizes suggested a significant effect of resveratrol administration on weight (weighted mean differences [WMD]: -0.51 kg, 95% confidence interval [CI]: -0.94 to -0.09; I²  = 50.3%, P = 0.02), BMI (WMD: -0.17 kg m^-2 , 95% CI: -0.32, -0.03; I²  = 49.6%, P = 0.02) and WC (WMD: -0.79 cm, 95% CI: -1.39, -0.2; I²  = 13.4%, P = 0.009), respectively. However, no significant effect of resveratrol supplementation on FM was found (WMD: -0.36%, 95% CI: -0.88, 0.15; I²  = 0.0%, P = 0.16). Findings from subgroup analysis revealed a significant reduction in BW and BMI in trials using resveratrol at the dosage of <500 mg d^-1 , those with long-term interventions (≥3 month), and performed on people with obesity. Taken together, the data suggest that resveratrol supplementation has beneficial effects to reduce BW, BMI and WC, but not FM.

Acute depletion of diacylglycerol from the cis-Golgi affects localized nuclear envelope morphology during mitosis

Dysregulation of nuclear envelope (NE) assembly results in various cancers; for example, renal and some lung carcinomas ensue due to NE malformation. The NE is a dynamic membrane compartment and its completion during mitosis is a highly regulated process, but the detailed mechanism still remains incompletely understood. Previous studies have found that isolated diacylglycerol (DAG)-containing vesicles are essential for completing the fusion of the NE in nonsomatic cells. We investigated the impact of DAG depletion from the cis-Golgi in mammalian cells on NE reassembly. Using advanced electron microscopy, we observed an enriched DAG population of vesicles at the vicinity of the NE gaps of telophase mammalian cells. We applied a mini singlet oxygen generator-C1-domain tag that localized DAG-enriched vesicles at the perinuclear region, which suggested the existence of NE fusogenic vesicles. We quantified the impact of Golgi-DAG depletion by measuring the in situ NE rim curvature of the reforming NE. The rim curvature in these cells was significantly reduced compared with controls, which indicated a localized defect in NE morphology. Our novel results demonstrate the significance of the role of DAG from the cis-Golgi for the regulation of NE assembly.

Polarized two-photon photoselection in EGFP: Theory and experiment

In this work, we present a complete theoretical description of the excited state order created by two-photon photoselection from an isotropic ground state; this encompasses both the conventionally measured quadrupolar (K = 2) and the "hidden" degree of hexadecapolar (K = 4) transition dipole alignment, their dependence on the two-photon transition tensor and emission transition dipole moment orientation. Linearly and circularly polarized two-photon absorption (TPA) and time-resolved single- and two-photon fluorescence anisotropy measurements are used to determine the structure of the transition tensor in the deprotonated form of enhanced green fluorescent protein. For excitation wavelengths between 800 nm and 900 nm, TPA is best described by a single element, almost completely diagonal, two-dimensional (planar) transition tensor whose principal axis is collinear to that of the single-photon S₀ → S₁ transition moment. These observations are in accordance with assignments of the near-infrared two-photon absorption band in fluorescent proteins to a vibronically enhanced S₀ → S₁ transition.

The association of neck circumference with risk of metabolic syndrome and its components in adults: A systematic review and meta-analysis

BACKGROUND & AIMS

Several prior studies suggested that neck circumference (NC) is a reliable diagnostic tool for risk of metabolic syndrome (MetS) and its features. However, not all studies support this view. Therefore, we aimed to perform a meta-analysis to summarize the association between NC with MetS and its components in adult populations.

METHODS AND RESULTS

PubMed/Medline, Web of Knowledge, and Scopus electronic databases were searched until May 31, 2017 to find relevant English-language papers. We included studies that examined the association of NC with risk of MetS, or at minimum, one of its components as outcomes. Of 2628 publications identified, 19 papers met selection criteria. We found no association between NC and MetS (odd ratio (OR): 0.73; 95% CI: 0.003, 1.47). However, there was a positive association between NC and waist circumference (WC) (r = 0.85; 95%: 0.75, 0.95; I²: 98.2%; p = 0.0001), BMI: (r:0.88; 95% CI: 0.74, 0.91, I²:97.3%), triglycerides (TG) (OR: 1.87; 95% CI: 1.60, 2.19; I²:58.4%; p = 0.03), TC (r:0.14; 95%CI: 0.05, 0.23, I²:94.1%), LDL-C (r: 0.18; 95%CI: 0.07, 0.29, I²:94.3%), hypertension (OR: 1.94; 95% CI:1.43, 2.64, I²:87.3%), systolic (r: 0.21, 95%CI: 0.19, 0.23; I²:67.1%) and diastolic blood pressures (r: 0.20, 95%CI: 0.16, 0.23; I²:79.7%), low HDL-C (r:-0.21; 95% CI: -0.26, -0.15, I² = 92.5%), as well as fasting blood sugar (FBS) concentrations (r: 0.20, 95%CI: 0.16, 0.24; I²:88.1%).

CONCLUSION

Subjects with higher NC were at approximately two-fold higher risk for hypertriglyceridemia compared to those with lower NC. We found positive associations between NC, WC, BMI, hypertension, FBS, TC, LDL-C, SBP, DBP, and low HDL-C concentrations. However, heterogeneity was considerably high. Therefore, the findings should be taken with caution. Future studies using longitudinal designs are needed to further understand the association between NC and features of MetS.

Peroxisome proliferator-activated receptor gamma expression in peripheral blood mononuclear cells and angiopoietin-like protein 4 levels in obese children and adolescents

PURPOSE

The peroxisome proliferator-activated receptor γ (PPARγ) is highly expressed in adipose tissue and functions as transcriptional regulator of metabolism and adipocyte differentiation. Angiopoietin-like protein 4 (ANGPTL4), a central player in various aspects of energy homoeostasis, is induced by PPARγ. The aim of this study was to evaluate ANGPTL4 plasma levels and PPARγ gene expression in peripheral blood mononuclear cells (PBMCs) of children and adolescents with obesity and their association with metabolic parameters.

METHODS

Seventy children and adolescents (35 obese and 35 age- and gender-matched control subjects), were selected. PBMCs were separated and their total RNA was extracted. After cDNA synthesis, PPARG gene expression was analyzed by real-time PCR. Relative differences in gene expression were calculated by ΔCt method using β-actin as a normalizer. Serum ANGPTL4 and insulin were measured using ELISA, and insulin resistance (IR) was calculated by the homeostatic model assessment of insulin resistance (HOMA-IR). Fasting plasma glucose (FPG), triglyceride, total cholesterol, LDL-C and HDL-C were also measured.

RESULTS

The expression of the PPARG gene as well as the plasma ANGPTL4 levels were significantly diminished in obese subjects as compared to control ones. However, they were not significantly different in obese children with IR compared to obese children without IR or in those with or without metabolic syndrome. A significant positive correlation was found between PPARγ and ANGPTL4 (r = 0.364, p = 0.002). PPARγ expression levels were also significantly correlated with FPG (r = -0.35, p = 0.003).

CONCLUSION

PPARγ is decreased in childhood obesity and may be responsible for diminished ANGPTL4 levels.

Quantifying intracellular equilibrium dissociation constants using single-channel time-resolved FRET

Quantification of the intracellular equilibrium dissociation constant of the interaction, K_d , is challenging due to the variability of the relative concentrations of the interacting proteins in the cell. Fluorescence lifetime imaging microscopy (FLIM) of the donor provides an accurate measurement of the molecular fraction of donor involved in FRET, but the fraction of bound acceptor is also needed to reliably estimate K_d . We present a method that exploits the spectroscopic properties of the widely used eGFP - mCherry FRET pair to rigorously determine the intracellular K_d based on imaging the fluorescence lifetime of only the donor (single-channel FLIM). We have assessed the effect of incomplete labelling and determined its range of application for different K_d using Monte Carlo simulations. We have demonstrated this method estimating the intracellular K_d for the homodimerisaton of the oncogenic protein 3-phosphoinositide-dependent kinase 1 (PDK1) in different cell lines and conditions, revealing a competitive mechanism for its regulation. The measured intracellular K_d was validated against in-vitro data. This method provides an accurate and generic tool to quantify protein interactions in situ.

Uncoupling TORC2 from AGC kinases inhibits tumour growth

Mammalian target of rapamycin (mTOR) is a central regulator of growth and metabolism. mTOR resides in two distinct multi-protein complexes - mTORC1 and mTORC2 - with distinct upstream regulators and downstream targets. While it is possible to specifically inhibit mTORC1 with rapamycin, or inhibit both mTOR complexes together with ATP pocket directed mTOR kinase inhibitors, it is not possible to assess the specific roles for mTORC2 pharmacologically. To overcome this, we have developed a novel, inducible, dominant negative system for disrupting substrate recruitment to mTORC2. Previously we identified the mTORC2 specific subunit Sin1 as a direct binding partner for AGC kinases Akt and PKC. Sin1 mutants, which retain the ability to bind Rictor and mTOR, but fail to recruit their AGC client kinases, inhibit AKT and PKC priming and block cell growth. In this study, we demonstrate that uncoupling mTORC2 from AGC kinases in DLD1 colon cancer cells inhibits Akt activation and blocks tumour growth in vivo. Further we demonstrate, using time resolved two-site amplified FRET (A-FRET) analysis of xenograft tumours, that inhibition of tumour growth correlates with the degree of mTORC2 uncoupling from its downstream targets, as demonstrated for Akt. These data add weight to the body of evidence that mTORC2 represents a pharmacological target in cancer independently of mTORC1.

Time resolved amplified FRET identifies protein kinase B activation state as a marker for poor prognosis in clear cell renal cell carcinoma

Purpose

Clear cell Renal Cell Carcinomas (ccRCC), the largest group of renal tumours, are resistant to classical therapies. The determination of the functional state of actionable biomarkers for the assessment of these adenocarcinomas is essential. The dysregulation of the oncoprotein, PKB/Akt has been linked with poor prognoses in human cancers.

Material & methods

We analysed the status of the PKB/Akt pathway in a representative tumour tissue microarray obtained from the primary tumours and their metastases in 60 ccRCC with long term follow up. We sought to define the evolution of this pathway from the primary tumour to the metastatic event and to know the impact of its functional state in tumour aggressiveness and patient survival. Two-site time resolved amplified FRET (A-FRET) was utilised for assessing the activation state of PKB/Akt and this was compared to conventional immunohistochemistry measurements.

Results

Activation state of PKB/Akt in primary tumours defined by A-FRET correlated with poorer overall survival (hazard ratio 0.228; p = 0.002). Whereas, increased protein expression of phosphoPKB/Akt, identified using classical immunohistochemistry, yielded no significant difference (hazard ratio 1.390; p = 0.548).

Conclusions

Quantitative determination of PKB/Akt activation in ccRCC primary tumours alongside other diagnostics tools could prove key in taking oncologists closer to an efficient personalised therapy in ccRCC patients.

General significance

The quantitative imaging technology based on Amplified-FRET can rapidly analyse protein activation states and molecular interactions. It could be used for prognosis and assess drug function during the early cycles of chemotherapy. It enables evaluation of clinical efficiency of personalised cancer treatment.

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Time Resolved Amplified FRET (A-FRET), has been used to quantitatively assess PKB/Akt activation states in ccRCC.

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Increased activation state of PKB/Akt in primary tumours was shown to correlate with poorer prognoses.

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Companion diagnostic tools such as A-FRET will prove valuable for assessing prognostic models and for predicting the response to systemic therapy.

Inverse association between cigarette and water pipe smoking and hypertension in an elderly population in Iran: Bushehr elderly health programme

The collected data in Bushehr Elderly Health (BEH) Program which had detailed the data on participants' smoking status and habits, was analysed to investigate the association between smoking of both water pipes and cigarettes and hypertension in an elderly population. Three thousand elderly men and women who participated in the baseline assessment of the BEH Program-a prospective population-based study being conducted in Bushehr, Iran-were selected randomly through a multistage, stratified cluster sampling method. Systolic and diastolic blood pressures were measured twice using a mercury sphygmomanometer, and researchers asked participants about medical history of hypertension as well as history of cigarette and water pipe smoking. Researchers used binary logistic regression models to assess the association of hypertension and smoking, and found an inverse, statistically significant association between current smoking and hypertension (odds ratio (OR)=0.50 (95% confidence interval (CI)=0.41, 0.60)). The association remained statistically significant after controlling for age, education and body mass index (OR=0.54 (95% CI=0.45, 0.66)). Findings were consistent for cigarette and water pipe smoking by sex (all ORs were inverse and statistically significant). Both cigarette and water pipe smoking were associated with reduced hypertension among older people, but the strength of association was different between men and women and also between cigarette and water pipe smoking. The reasons behind the association as well as the differences observed need to be investigated through more comprehensive, longitudinal studies.

Vesicular PtdIns(3,4,5)P3 and Rab7 are key effectors of sea urchin zygote nuclear membrane fusion

Regulation of nuclear envelope dynamics is an important example of the universal phenomena of membrane fusion. The signalling molecules involved in nuclear membrane fusion might also be conserved during the formation of both pronuclear and zygote nuclear envelopes in the fertilised egg. Here, we determine that class-I phosphoinositide 3-kinases (PI3Ks) are needed for in vitro nuclear envelope formation. We show that, in vivo, PtdIns(3,4,5)P₃ is transiently located in vesicles around the male pronucleus at the time of nuclear envelope formation, and around male and female pronuclei before membrane fusion. We illustrate that class-I PI3K activity is also necessary for fusion of the female and male pronuclear membranes. We demonstrate, using coincidence amplified Förster resonance energy transfer (FRET) monitored using fluorescence lifetime imaging microscopy (FLIM), a protein-lipid interaction of Rab7 GTPase and PtdIns(3,4,5)P₃ that occurs during pronuclear membrane fusion to create the zygote nuclear envelope. We present a working model, which includes several molecular steps in the pathways controlling fusion of nuclear envelope membranes.

Adherence to Healthy Eating Index-2010 is inversely associated with metabolic syndrome and its features among Iranian adult women

BACKGROUND/OBJECTIVES

Nowadays, metabolic syndrome (MetS) is deemed as a major public health challenge in both developed and developing countries. Therefore, the aim of this study was to determine the association between Healthy Eating Index-2010 (HEI-2010) score and MetS and its features among Iranian female nurses.

SUBJECTS/METHODS

This cross-sectional study was performed among 1036 Iranian women. A validated, self-administered, dish-based, semiquantitative food frequency questionnaire was used to assess the habitual intake of participants. HEI-2010 score was used to assess diet quality of participants. MetS was defined based on the guidelines of the National Cholesterol Education Program Adult Treatment Panel III (ATP III). Multivariate logistic regression adjusted for potential confounders was used to assess the relation between HEI-2010 and MetS.

RESULTS

After adjusting for potential confounders, participants in the highest quartile of HEI-2010 had the lowest risk of MetS compared with those in the first quartile (odds ratio: 0.72; 95% confidence interval: 0.50-0.96). Furthermore, the risk of MetS features including abdominal obesity, high blood pressure, high serum triacylglycerol and low serum high-density lipoprotein-cholesterol significantly decreased across HEI-2010 quartiles (P<0.05).

CONCLUSIONS

Higher HEI-2010 scores were inversely associated with lower risk of MetS and its components among Iranian women.

Gut Microbiota as a Target in the Pathogenesis of Metabolic Disorders: A New Approach to Novel Therapeutic Agents

As the prevalence of metabolic disorders increases dramatically, the importance of identifying environmental factors affecting metabolism control becomes greater accordingly. Gut microbiota, a complex ecosystem inhabiting the human gastrointestinal tract, is one of these potential factors. Recently, the evidence has shown the associations between alteration in gut microbiota composition and obesity, diabetes, and osteoporosis. However, the causality of gut microbiota on metabolic health has yet to be explored in intervention studies and the underlying mechanisms need to be investigated more in depth. Gut microbiota plays critical roles in the control of immunity, food intake, lipid accumulation, production of short chain fatty acids, insulin signaling, and regulation of bone mass. The gut microbiota represents a novel potential therapeutic strategy for the treatment of metabolic disorders. In this review, we provide insights into the role of the gut microbiota in metabolic disorders and its modulating interventions such as prebiotics, probiotics, and fecal microbiota transplantation.

Polymorphonuclear leucocyte respiratory burst activity correlates with serum zinc level in type 2 diabetic patients with foot ulcers

Patients with diabetes mellitus (DM) are prone to infection, in part due to phagocyte dysfunction and impaired polymorphonuclear (PMN) leucocyte superoxide generation. Another frequently mentioned factor in the pathogenesis of infection in DM patients is altered zinc status. This study aims to evaluate the association between serum zinc level and PMN respiratory burst activity in patients with type 2 DM. Thirty-nine type 2 DM patients (19 with foot ulcers) and 20 healthy controls are studied. Respiratory burst activity is evaluated at baseline and in stimulated states by a nitro blue tetrazolium (NBT) reduction test. Serum zinc level is evaluated by atomic absorption spectrophotometry. Although not statistically significant, PMNs from diabetics with foot ulcers appeared to be slightly hyperactivated at the baseline state. The NBT index was significantly lower in DM patients with foot ulcers after stimulation. Mean serum zinc level was significantly lower in diabetics with foot ulcers compared to those without foot ulcers. A significant negative correlation between serum zinc level and NBT index at baseline was seen in patients with foot ulcers, but this changed to a significant positive correlation after stimulation. These findings may be explained by PMN hyperactivity at baseline and by respiratory burst dysfunction following stimulation in diabetic patients.

The Use of Two-Photon FRET-FLIM to Study Protein Interactions During Nuclear Envelope Fusion In Vivo and In Vitro

FRET-FLIM techniques have wide application in the study of protein and protein-lipid interactions in cells. We have pioneered an imaging platform for accurate detection of functional states of proteins and their interactions in fixed cells. This platform, two-site-amplified Förster resonance energy transfer (a-FRET), allows greater signal generation while retaining minimal noise thus enabling application of fluorescence lifetime imaging microscopy (FLIM) to be routinely deployed in different types of cells and tissue. We have used the method described here, time-resolved FRET monitored by two-photon FLIM, to demonstrate the direct interaction of Phospholipase Cγ (PLCγ) by Src Family Kinase 1 (SFK1) during nuclear envelope formation and during male and female pronuclear membrane fusion in fertilized sea urchin eggs. We describe here a generic method that can be applied to monitor any proteins of interest.

Conservation of proteo-lipid nuclear membrane fusion machinery during early embryogenesis

The fusogenic lipid diacylglycerol is essential for remodeling gamete and zygote nuclear envelopes (NE) during early embryogenesis. It is unclear whether upstream signaling molecules are likewise conserved. Here we demonstrate PLCγ and its activator SFK1, which co-operate during male pronuclear envelope formation, also promote the subsequent male and female pronuclear fusion. PLCγ and SFK1 interact directly at the fusion site leading to PLCγ activation. This is accompanied by a spatially restricted reduction of PtdIns(4,5)P2. Consequently, pronuclear fusion is blocked by PLCγ or SFK1 inhibition. These findings identify new regulators of events in the early embryo and suggest a conserved "toolkit" of fusion machinery drives successive NE fusion events during embryogenesis.

Endomembrane PtdIns(3,4,5)P3 activates the PI3K-Akt pathway

PKB/Akt activation is a common step in tumour growth, proliferation and survival. Akt activation is understood to occur at the plasma membrane of cells in response to growth factor stimulation and local production of the phosphoinositide lipid phosphatidylinositol (3,4,5)-trisphosphate [PtdIns(3,4,5)P3] following phosphoinositide 3-kinase (PI3K) activation. The metabolism and turnover of phosphoinositides is complex--they act as signalling molecules as well as structural components of biological membranes. The localisation and significance of internal pools of PtdIns(3,4,5)P3 has long been speculated upon. By using transfected and recombinant protein probes for PtdIns(3,4,5)P3, we show that PtdIns(3,4,5)P3 is enriched in the nuclear envelope and early endosomes. By exploiting an inducible dimerisation device to recruit Akt to these compartments, we demonstrate that Akt can be locally activated in a PtdIns(3,4,5)P3-dependent manner and has the potential to phosphorylate compartmentally localised downstream substrates. This could be an important mechanism to regulate Akt isoform substrate specificity or influence the timing and duration of PI3K pathway signalling. Defects in phosphoinositide metabolism and localisation are known to contribute to cancer, suggesting that interactions at subcellular compartments might be worthwhile targets for therapeutic intervention.

Association between alterations in global DNA methylation and predisposing factors in diabetes: a high pressure liquid chromatography based study

AIM

The aim of this study was to investigate the relationship between inter-individual global DNA methylation and diabetes predisposing factors.

METHODS

The 5-methyl cytosine content was assessed by reverse phase high pressure liquid chromatography (RP-HPLC) of peripheral blood leukocytes obtained from 178 type 2 diabetes patients to determine individual global DNA methylation status.

RESULTS

There was a positive significant correlation between diabetes duration and DNA methylation levels (P=0.002) with increasing levels of DNA methylation associated with age (P=0.047). There was no significant correlation between DNA methylation levels and HbA1c (P=0.15). No significant differences were observed between patients with and without diabetes predisposing factors including: hypertension (P=0.772), dyslipidemia (P=0.617), insulin resistance (homeostatic model assessment index) (P=0.156) and obesity (P=0.609). As such, the duration of diabetes (>10 years) was the most important predictor of global DNA methylation levels in diabetic patients after adjusting for age and sex (P=0.023).

CONCLUSION

Our findings indicate that chronic hyperglycemic exposure plays an independent role in global DNA methylation levels in type 2 diabetes patients.

Managing diabetes mellitus using information technology: a systematic review

Objective

To review published evidences about using information technology interventions in diabetes care and determine their effects on managing diabetes.

Design

Systematic review of information technology based interventions.

Research design and methods

MEDLINE®/PubMed were electronically searched for articles published between 2004/07/01 and 2014/07/01. A comprehensive, electronic search strategy was used to identify eligible articles.

Inclusion criteria were defined based on type of study and effect of information technology based intervention in relation to glucose control and other clinical outcomes in diabetic patients. Studies must have used a controlled design to evaluate an information technology based intervention.

A total of 3613 articles were identified based on the searches conducted in MEDLINE from PubMed. After excluding duplicates (n = 6), we screened titles and abstracts of 3607 articles based on inclusion criteria. The remaining articles matched with inclusion criteria (n = 277) were reviewed in full text, and 210 articles were excluded based on exclusion criteria. Finally, 67 articles complied with our eligibility criteria and were included in this study.

Results

In this study, the effect of various information technology based interventions on clinical outcomes in diabetic patients extracted and measured from selected articles is described and compared to each other.

Conclusion

Information technology based interventions combined with the usual care are associated with improved glycemic control with different efficacy on various clinical outcomes in diabetic patients.

Association between breakfast intake with anthropometric measurements, blood pressure and food consumption behaviors among Iranian children and adolescents: the CASPIAN-IV study

OBJECTIVE

The aim of this study is to assess the association between breakfast intake with anthropometric measurements and blood pressure among Iranian children and adolescents. The second goal is to investigate the correction of breakfast consumption with other food consumption behaviors.

RESEARCH METHODS & PROCEDURES

In this national survey, 13,486 children and adolescents, aged 6-18 years, were selected by multistage, cluster sampling method from rural and urban areas of 31 provinces of Iran (2011-2012). Physical measurements included height, weight, waist circumference, and blood pressure. Food habits were assessed by self-reported questionnaire. Breakfast frequency was defined as skippers (eating breakfast 0-2 days/week), semi-skippers (eating breakfast 3-4 days/week) and non-skippers (eating breakfast 5-7 days/week). The data were analyzed by the STATA package.

RESULTS

Of the participants, 18.9%, 13.2% and 67.9%, were breakfast skippers, semi-skippers and non-skippers respectively. The prevalence of overweight and obesity among breakfast skippers were higher than non-skippers counterparts (P-value < 0.001). The percentage rates of abdominal obesity among breakfast skippers and non-skippers group were 22.6% (CI 95%: 21-24.3) and 17.9% (CI 95%: 17-18.6), respectively. Blood pressure did not significantly differ between non-skippers students and breakfast skippers (P-value = 0.1). Non-skipping adolescents ate more fresh fruits, dried fruits, vegetables and drank milk more frequently compared with breakfast skipper; while the skippers showed a higher intake of salty snack, soft drinks, packed fruit juice and fast foods (all P-value < 0.001).

CONCLUSION

Regular breakfast consumption is significantly associated with lower body fatness and healthier dietary habits but that further study, using controlled intervention trials, is required to test whether this represents a causal relationship.

Acute regulation of PDK1 by a complex interplay of molecular switches

Phosphoinositide-dependent kinase 1 (PDK1) is the master regulator of at least 23 other AGC kinases whose downstream signalling has often been implicated in various diseases and in particular in cancer. Therefore there has been great interest in determining how PDK1 is controlled and how it regulates its substrates spatially and temporally. The understanding of these mechanisms could offer new possibilities for therapeutic intervention. Over the years, a more comprehensive view of the mechanisms involved in the regulation of PDK1 has emerged and these comprise serine/threonine as well as tyrosine phosphorylation, subcellular localization, regulator binding and conformation status. In the present review, we discuss how various molecular mechanisms are together responsible for the conformational regulation behind the activation of PDK1 in cells.

High-throughput time-resolved FRET reveals Akt/PKB activation as a poor prognostic marker in breast cancer

Dysregulation of the Akt/PKB pathway has been associated with poor prognosis in several human carcinomas. Current approaches to assess Akt activation rely on intensity-based methods, which are limited by the subjectivity of manual scoring and poor specificity. Here, we report the development of a novel assay using amplified, time-resolved Förster resonance energy transfer (FRET), which is highly specific and sensitive and can be adapted to any protein. Using this approach to analyze primary breast tissue microarrays, we quantified levels of activated pAkt at a spatial resolution that revealed molecular heterogeneity within tumors. High pAkt status assessed by amplified FRET correlated with worse disease-free survival. Our findings support the use of amplified FRET to determine pAkt status in cancer tissues as candidate biomarker for the identification of high-risk patients.

Vitamin D status of type 2 diabetic patients compared with healthy subjects in the Islamic Republic of Iran

An inverse relationship has been shown between vitamin D deficiency and type 2 diabetes mellitus (DM). In this cross-sectional study in Tehran, Islamic Republic of Iran, a country with a high prevalence of vitamin D deficiency, we determined the prevalence of vitamin D deficiency among 90 type 2 DM patients and 90 healthy subjects. Based on serum levels of 25-hydroxyvitamin D, the rates of deficiency (< 50 nmol/L) and insufficiency (50-75 nmol/L) were 59.0% and 27.0% respectively in patients with type 2 DM, and 47.0% and 24.0% respectively in healthy subjects. Using the national cut-offs for vitamin D deficiency, 64.0% women with DM and 47.4% of healthy women were suffering from different degrees of vitamin D deficiency. The prevalence of vitamin D deficiency in men with type 2 DM and healthy men were 42.7% and 22.2% respectively. None of the differences between the 2 groups was statistically significant.