Mid-upper arm circumference as a screening tool for identifying children with obesity: a 12-country study

BACKGROUND

No studies have examined if mid-upper arm circumference (MUAC) can be an alternative screening tool for obesity in an international sample of children differing widely in levels of human development.

OBJECTIVE

Our aim is to determine whether MUAC could be used to identify obesity in children from 12 countries in five major geographic regions of the world.

METHODS

This observational, multinational cross-sectional study included 7337 children aged 9-11 years. Anthropometric measurements were objectively assessed, and obesity was defined according to the World Health Organization reference data.

RESULTS

In the total sample, MUAC was strongly correlated with adiposity indicators in both boys and girls (r > 0.86, p < 0.001). The accuracy level of MUAC for identifying obesity was high in both sexes and across study sites (overall area under the curve of 0.97, sensitivity of 95% and specificity of 90%). The MUAC cut-off value to identify obesity was ~25 cm for both boys and girls. In country-specific analyses, the cut-off value to identify obesity ranged from 23.2 cm (boys in South Africa) to 26.2 cm (girls in the UK).

CONCLUSIONS

Results from this 12-country study suggest that MUAC is a simple and accurate measurement that may be used to identify obesity in children aged 9-11 years. MUAC may be a promising screening tool for obesity in resource-limited settings.

CSR1 suppresses tumor growth and metastasis of human hepatocellular carcinoma via inhibition of HPIP

OBJECTIVE

Cellular stress response 1 (CSR1) is a tumor suppressor gene that was frequently down-regulated in prostate cancer. CSR1 has critical roles in the regulation of cell apoptosis via inactivation of CPSF3 or preventing the interaction of XIAP with caspases. However, whether CSR1 plays a role in human hepatocellular carcinoma (HCC) is completely unknown.

PATIENTS AND METHODS

The expression of CSR1 in HCC clinic samples and cell lines was detected by Real-time PCR and Western blot. CRISPR (clustered regularly interspaced short palindromic repeats)/Cas9 system was used to knockout CSR1 gene in HepG2 cells. The proliferation of HCC cells was measured by MTT assay. The migration and invasion abilities of HepG2 cells were determined by in vitro scratch wounding and matrigel invasion assays. Co-immunoprecipitation assay was used to determine the interaction between CSR1 and hematopoietic PBX interacting protein (HPIP).

RESULTS

The mRNA and protein levels of CSR1 were down-regulated in human HCC cell lines and clinic HCC tissues. Over-expression of CSR1 inhibited cell proliferation, migration and invasion in human HCC cell lines. Knockout of CSR1 gene by CRISPR-Cas9 in HepG2 cells achieved the opposite effects. At the molecular level, we found that CSR1 associated with HPIP and inhibited the activation PI3K/AKT pathway.

CONCLUSIONS

For the first time we demonstrated that CSR1 inhibited HCC cell proliferation, migration and invasion through inactivation of HPIP and its downstream PI3K/AKT signaling pathway and suggested CSR1 as a potential therapy target for HCC treatment.

Associations between meeting combinations of 24-h movement guidelines and health-related quality of life in children from 12 countries

OBJECTIVES

To examine whether meeting vs not meeting movement/non-movement guidelines (moderate-to-vigorous physical activity [MVPA], screen time, sleep duration), and combinations of these recommendations, are associated with health-related quality of life (HRQoL) in children from 12 countries in five major geographic regions of the world and explore whether the associations vary by study site.

STUDY DESIGN

Observational, multinational cross-sectional study.

METHODS

This study included 6106 children aged 9-11 years from sites in Australia, Brazil, Canada, China, Colombia, Finland, India, Kenya, Portugal, South Africa, the United Kingdom, and the United States. Participants completed the KIDSCREEN-10 to provide a global measure of their HRQoL. Sleep duration and MVPA were assessed using 24-h accelerometry. Screen time was assessed through self-report. Meeting the recommendations was defined as ≥60 min/day for MVPA, ≤2 h/day for screen time, and between 9 and 11 h/night for sleep duration. Age, sex, highest parental education, unhealthy diet pattern score, and body mass index z-score were included as covariates in statistical models.

RESULTS

In the full sample, children meeting the screen time recommendation, the screen time + sleep recommendation, and all three recommendations had significantly better HRQoL than children not meeting any of these guidelines. Differences in HRQoL scores between sites were also found within combinations of movement/non-movement behaviors. For example, while children in Australia, Canada, and USA self-reported better HRQoL when meeting all three recommendations, children in Kenya and Portugal reported significantly lower HRQoL when meeting all three recommendations (relative to not meeting any).

CONCLUSIONS

Self-reported HRQoL is generally higher when children meet established movement/non-movement recommendations. However, differences between study sites also suggest that interventions aimed at improving lifestyle behaviors and HRQoL should be locally and culturally adapted.

Population dynamics of rice planthoppers, Nilaparvata lugens and Sogatella furcifera (Hemiptera, Delphacidae) in Central Vietnam and its effects on their spring migration to China

Rice planthopper (RPH) populations of Nilaparvata lugens and Sogatella furcifera periodically have erupted across Asia. Predicting RPH population dynamics and identifying their source areas are crucial for the management of these migratory pests in China, but the origins of the migrants to temperate and subtropical regions in China remains unclear. In particular, their early migration to China in March and April have not yet been explored due to a lack of research data available from potential source areas, Central Vietnam and Laos. In this study, we examined the population dynamics and migratory paths of N. lugens and S. furcifera in Vietnam and South China in 2012 and 2013. Trajectory modeling showed that in March and April in 2012 and 2013, RPH emigrated from source areas in Central Vietnam where rice was maturing to the Red River Delta and South China. Early migrants originated from Southern Central Vietnam (14-16°N), but later most were from Northern Central Vietnam (16-19°N). Analysis of meteorological and light-trap data from Hepu in April (1977-2013) using generalized linear models showed that immigration increased with precipitation in Southern Central Vietnam in January, but declined with precipitation in Northern Central Vietnam in January. These results determined that the RPH originate from overwintering areas in Central Vietnam, but not from southernmost areas of Vietnam. Winter precipitation, rather than temperature was the most important factor determining the number of RPH migrants. Based on their similar population dynamics and low population densities in Central Vietnam, we further speculated that RPH migrate to track ephemeral food resources whilst simultaneously avoiding predators. Migrations do not seem to be initiated by interspecific competition, overcrowding or host deterioration. Nevertheless, S. furcifera establishes populations earlier than N. lugens South China, perhaps to compensate for interspecific competition. We provide new information that could assist with forecasting outbreaks and implementing control measures against these migratory pests.

Hypertensive disorders of pregnancy in women with gestational diabetes mellitus on overweight status of their children

Hypertensive disorders of pregnancy (HDP) as a group of medical complications in pregnancy are believed to be associated with an increased risk of poor fetal growth, but the influence on offspring’s body composition is not clear. The aim of the present study was to evaluate the association between maternal hypertensive disorders of pregnancy and overweight status in the offspring of mothers with gestational diabetes mellitus (GDM).

A cross-sectional study among 1263 GDM mother-child pairs was performed in Tianjin, China. General linear models and logistic regression models were used to assess the associations of maternal hypertension in pregnancy with anthropometry and overweight status in the offspring from birth to 1–5 years old.

Offspring of GDM mothers who were diagnosed with hypertensive disorders during pregnancy had higher mean values of Z scores for birth weight for gestational age and birth weight for length, and higher mean values of Z scores for weight for age, weight for length/height, and body mass index for age at 1–5 years old than those of GDM mothers with normal blood pressure during pregnancy. Maternal hypertensive disorders of pregnancy were associated with increased risks of large for gestational age (OR 1.74, 95%CI 1.08–2.79) and macrosomia (OR 2.02, 95%CI 1.23–3.31) at birth and childhood overweight/obesity at 1–5 years old age (OR 1.88, 95%CI 1.16–3.04).

For offspring of mothers with GDM, maternal hypertension during pregnancy was a risk factor for macrosomia at birth and childhood overweight and obesity, and controlling the maternal hypertension may be more important for preventing large for gestational age babies and childhood obesity.

Degradation of methomyl by the combination of Aminobacter sp. MDW-2 and Afipia sp. MDW-3

Methomyl (S-methyl N-(methylcarbamoyloxy) thioacetimidate) is a kind of oxime carbamate insecticide. It is considered to be extremely toxic to nontarget organism. To date, no pure culture or consortium has been reported to have the ability to degrade methomyl completely. In this study, a methomyl-degrading enrichment E1 was obtained by using the sludge from the wastewater-treating system of a pesticide manufacturer as the original inoculant. Two bacterial strains named MDW-2 and MDW-3 were isolated from this enrichment, and they were preliminarily identified as Aminobacter sp. and Afipia sp. respectively. Strains MDW-2 and MDW-3 could coexist and degrade 50 mg l^-1 methomyl completely within 3 days by the cooperative metabolism. Methomyl was first converted to methomyl oxime and methylcarbamic acid by strain MDW-2, and the latter could be used as the carbon source for the growth of strain MDW-2. But methomyl oxime could not be sequentially degraded by strain MDW-2. However, it could be degraded and used as the carbon source by strain MDW-3.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study presents a bacterial combination of Aminobacter sp. MDW-2 and Afipia sp. MDW-3, which could degrade methomyl completely by biochemical cooperation. This study also proposes the biodegradation pathway of methomyl for the first time and highlights the application potential of a bacterial combination in the remediation of methomyl-contaminated environments.

Abstract P4-01-02: Diagnostic value of breast specific gamma imaging for breast cancer

In this study, 422 female patients who presented with clinical indications and underwent ultrasound (US), mammography (MMG), and breast specific gamma imaging (BSGI) before surgery during the period from July 2013 to June 2015 were retrospectively reviewed. Twenty-two of the patients had no pathological report available and were excluded. These patients who presented with clinical indications underwent both ultrasound and mammographic examinations initially. If both US and MMG were positive, the patient was recommended for a BSGI examination for pre-surgical planning. A BSGI examination was also recommended for patients with negative or indeterminate mammographic findings.

The diagnostic results were compared with histological examination and the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for each modality were determined. Combinations of either two or three of the diagnostic results were also reviewed and the corresponding diagnostic indicators calculated. For these combinations, a positive indication on one of the two (or three) diagnostic tests were interpreted as a positive result. The sensitivity of US, MMG, BSGI, the combination of US and MMG, US and BSGI, MMG and BSGI, and the combination of all three together in the diagnosis of breast carcinoma were determined for the 400 patients included in the study and are listed in Table 1, column 1. The specificity, PPV, and NPV for each of these modalities and combinations of modalities were also determined and are shown Table 1, column 2-4.

Table 1 SensitivitySpecificityPPVNPVUS61.389.289.759.8MMG67.594.394.765.2BSGI83.187.991.477.1US & MMG86.884.789.880.6US & BSGI91.382.889.186.1MMG & BSGI92.283.489.585.6US & MMG & BSGI97.579.087.895.4

The population was comprised of 243 patients with 245 malignant lesions and 157 patients with 189 benign lesions. The malignant lesions were primarily infiltrating ductal carcinoma (76%) and ductal carcinoma in situ (14%), with the remaining lesions (10%) being invasive lobular carcinoma, Paget's disease and mixed carcinomas. The benign lesions were primarily fibroadenoma (39%), adenosis (40%) and papilloma (10%), with the remaining lesions (11%) being duct ectasia, inflammation or phyllodes. There were 79 false negative cases by MMG, however, when ultrasound and BSGI were combined, 73 out of 79 were accurately identified. Additionally, there were nine, seventeen and eighteen Ductal Carcinoma in situ (DCIS) misdiagnosed by BSGI, MMG, and ultrasound respectively, but through joint imaging of BSGI+MMG+US; 33 out of 35 were accurately judged.

BSGI is a useful adjunct modality for the diagnosis of breast carcinoma. It is also extremely useful for diagnosis of non-calcified DCIS, and circumvents limitations of mammography in identifying malignant lesion in dense breast. Moreover, it is helpful for improving the diagnosis accuracy of breast carcinoma when BSGI is combined together with MMG and US.

Citation Format: Mallik DK, Zhang H, Shi H, Tan H, Shen L, Hu G, Hu H, Sejdinaj F, Pang Y, Zhu W, Yang W. Diagnostic value of breast specific gamma imaging for breast cancer [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P4-01-02.

Aberrant activation of hedgehog signaling promotes cell proliferation via the transcriptional activation of forkhead Box M1 in colorectal cancer cells

BACKGROUND

Recent evidence suggests that the aberrant activation of Hedgehog (Hh) signaling by Gli transcription factors is characteristic of a variety of aggressive human carcinomas, including colorectal cancer (CRC). Forkhead box M1 (FoxM1) controls the expression of a number of cell cycle regulatory proteins, and FoxM1 expression is elevated in a broad range of human malignancies, which suggests that it plays a crucial role in tumorigenesis. However, the mechanisms underlying FoxM1 expression are not fully understood. Here, we aim to further investigate the molecular mechanism by which Gli1 regulates FoxM1 in CRC.

METHODS

Western blotting and immunohistochemistry (IHC) were used to evaluate FoxM1 and Gli1 protein expression, respectively, in CRC tissues and matched adjacent normal mucosa. BrdU (5-bromo-2'-deoxyuridine) and clone formation assays were used to clarify the influence of FoxM1 on CRC cell growth and proliferation. Chromatin immunoprecipitation (ChIP) and luciferase experiments were performed to explore the potential mechanisms by which Gli1 regulates FoxM1. Additionally, the protein and mRNA expression levels of Gli1 and FoxM1 in six CRC cell lines were measured using Western blotting and real-time PCR. Finally, the effect of Hh signaling on the expression of FoxM1 was studied in cell biology experiments, and the effects of Hh signaling activation and FoxM1 inhibition on the distribution of CRC cells among cell cycle phases was assessed by flow cytometry.

RESULTS

Gli1 and FoxM1 were abnormally elevated in human CRC tissues compared with matched adjacent normal mucosa samples, and FoxM1 is a downstream target gene of the transcription factor Gli1 in CRC and promoted CRC cell growth and proliferation. Moreover, the aberrant activation of Hh signaling promoted CRC cell proliferation by directly binding to the promoter of FoxM1 and transactivating the activity of FoxM1 in CRC cells.

CONCLUSION

The dysregulation of the Hh-Gli1-FoxM1 axis is essential for the proliferation and growth of human CRC cells and offers a potent target for therapeutic intervention in CRC.

Sleep duration and quality, and risk of gestational diabetes mellitus in pregnant Chinese women

AIMS

To examine the association between sleep disturbances during pregnancy and risk of gestational diabetes mellitus.

METHODS

From 2010 to 2012, 12 506 women in Tianjin, China, were screened using a 50-g 1-h glucose challenge test at 24-28 weeks' gestation. Those with glucose challenge test values of ≥ 7.8 mmol/l were invited to further undergo a 75-g 2-h oral glucose tolerance test. Gestational diabetes was determined according to the International Association of Diabetes and Pregnancy Study Group's definition. Self-reported sleep duration and sleep quality during pregnancy was documented using a modified questionnaire. Logistic regression was used to obtain odds ratios and 95% CIs.

RESULTS

A total of 919 women (7.3%) had gestational diabetes. Sleep duration was found to have an approximate J-shaped association with gestational diabetes risk after adjusting for covariates. Compared with a sleep duration of 7-9 h/day (43% of 12 506 women), the adjusted odds ratios for sleep duration of ≥ 9 h/day (55%) and < 7 h/day (2%) for gestational diabetes were 1.21 (95% CI 1.03-1.42) and 1.36 (95% CI 0.87-2.14), respectively. Compared with good sleep quality (37.9% of 12 506 women), the adjusted odds ratios of moderate (59.9%) and poor sleep quality (2.2%) for gestational diabetes were 1.19 (95% CI 1.01-1.41) and 1.61 (95% CI 1.04-2.50), respectively.

CONCLUSION

In pregnant Chinese women, poor sleep quality, and shorter and longer duration of sleep during pregnancy were independently associated with an increased risk of gestational diabetes.

In vivo effects of high dietary copper levels on hepatocellular mitochondrial respiration and electron transport chain enzymes in broilers

The diet of broiler chickens supplemented with increasing concentrations of copper (Cu) was assessed for the effect of Cu on liver mitochondrial function. A total of 160, 1-d-old Cobb 500 broilers (Gallus domesticus) were randomly assigned in equal numbers into 4 groups, which differed in the concentration of copper supplements in the diet; 11 (control), 110, 220 and 330 mg of Cu/kg dry matter. Liver mitochondrial function was recorded at 12, 24, 36, 48 and 60 d of age. Supplementation with 110 mg Cu/kg dry matter enhanced mitochondrial function and activities of complexes I-V, and this was significant at 36 d of age compared with the other diets (P < 0.05). Supplementation with 220 mg Cu/kg dry matter and 330 mg Cu/kg dry matter enhanced mitochondrial function and activities of complexes I-V at 12, 24 and 36 d of age, but displayed reduced function (P < 0.05) at 48 and 60 d of age except in complex IV (P > 0.05). Mitochondrial hydrogen peroxide (H2O2) production was also increased (P < 0.05) with an increase of copper supplementation in the diet. The results indicate that appropriate dietary copper supplements are sufficient for improving mitochondrial function and activities of the respiratory complexes. Higher concentrations of copper, on the other hand, lead to copper toxicity by affecting certain respiratory complexes.

A System for the Comprehensive Quantification of Real-Time Heartbeat Activity

Heartbeat can reflect the dynamics of the heart control system, and it is also a commonly used index in health monitoring, exercise load calculation and psycho-physiological arousal quantification. This paper fuses three heartbeat measures, i.e. the running mean, the range of local Hurst exponents and the relative fluctuation, to construct a system that can automatically quantify the heartbeat activity both from its static aspect and from its dynamic aspect in a real-time manner. Experiments show that the system can reveal the heartbeat arousal difference between physically relaxed status and exercise-loaded status. When the affective heartbeat data in literature are quantified by this system, the results also show the capability of the system to illustrate psycho-physiological arousal.

The microRNA-182-PDK4 axis regulates lung tumorigenesis by modulating pyruvate dehydrogenase and lipogenesis

Reprogrammed metabolism is one of the hallmarks of cancer. The dysregulation of glycolysis in cancer has been heavily studied. However, it remains largely unclear how other metabolic processes are regulated in cancer cells. Here we show that microRNA-182 (miR-182) suppresses pyruvate dehydrogenase (PDH) kinase 4 (PDK4) and promotes lung tumorigenesis. miR-182 is dysregulated and inversely correlated with PDK4 in human lung adenocarcinomas. The miR-182-PDK4 axis regulates lung cancer cell growth by modulating the activity of PDH, the gatekeeping enzyme of pyruvate flux into acetyl-CoA, and subsequently de novo lipogenesis of cancer cells. Suppression of lipogenesis by silencing ATP citrate lyase (ACLY) and fatty acid synthase (FASN) or by chemical inhibitors diminishes the effects of miR-182-PDK4 in tumor growth. Alteration of de novo lipogenesis also affects reactive oxygen species (ROS) production and the downstream JNK signaling pathway. Hence, our work suggests that the miR-182-PDK4 axis is a crucial regulator of cancer cell metabolism and a potential target for antitumor therapy.

Dorsal open reduction with pedicle screw rod internal fixation for lower cervical spine dislocation: A retrospective analysis of 12 cases

BACKGROUND

Lower cervical spine dislocation remains a surgical challenge.

METHODS

Twelve patients with lower cervical dislocation due to articular process injury underwent dorsal open reduction and manual pedicle screw rod fixation. Patients with cervical spinal cord injury received simultaneous open door expansive laminoplasty. Neurological function was evaluated using ASIA Impairment Scale 12.

RESULTS

Median time from injury to operation was 10 days (range, 5 to 52 days). Anatomic reduction was achieved in all patients. In nine patients with cervical spinal cord injury, 55.5% (5/9) showed improvement in ASIA grade following surgery. Unilateral numbness of the superior radicular area in one patient resolved 2 weeks post-surgery and two cases (11.1%, 2/9) had postoperative leakage of the cerebrospinal fluid, which resolved in 11 days and 13 days, respectively.

CONCLUSION

Dorsal open reduction and manual pedicle screw rod fixation is safe and effective for lower cervical spine dislocation due to articular process injury.

The role of 18F-FDG PET/CT in the management of patients with secondary haemophagocytic lymphohistiocytosis

AIM

To investigate the ability of combined 2-[¹⁸F]-fluoro-2-deoxy-d-glucose (¹⁸F-FDG) positron-emission tomography (PET)/computed tomography (CT) to determine potential causes of secondary haemophagocytic lymphohistiocytosis (sHLH) and to predict prognosis.

MATERIAL AND METHODS

Forty-three patients (male/female 20/23, median age 48.5 years), who were diagnosed with sHLH and underwent FDG-PET/CT before treatment, were retrospectively reviewed. The clinical characteristics were compared to identify the predictors of high-yield FDG-PET/CT. Univariate and multivariate analyses were conducted to identify factors associated with survival. Statistical analysis was performed using SPSS version 19.0.

RESULTS

PET results were helpful in 65.1% (28/43), whilst non-contributory in 34.9% (15/43) of patients with regard to the final diagnosis. Lymphoma was the most common (25/43) reason for sHLH, and patients with focal FDG uptake were more likely to be diagnosed with underlying diseases. C-reactive protein (CRP) was found to be a good indicator for the usefulness of PET/CT in HLH patients. Multivariate analysis showed that therapy regimen (hazard ratio [HR]=4.99, p=0.026), fibrinogen (FBG) <1.5 g/l (HR=3.87, p=0.049) and spleen:mediastinum ratio (SP/M) (HR=7.44, p=0.006) were independent prognostic factors for survival.

CONCLUSION

FDG-PET/CT could be a useful technique for detecting underlying diseases causing sHLH. CRP was a useful predictor of FDG-PET/CT effectiveness. Therapy regimen, FBG level, and SP/M were independent prognostic factors for HLH survival.

Mechanism underlying the bio-effects of an electromagnetic field based on the Huang-Ferrell model

To understand the beneficial and harmful bio-effects of extremely low frequency electromagnetic fields, we studied the MAPK/ERK signaling pathway based on the Huang-Ferrell model. The sensitivity analysis method was used to study the influence of the model parameters on the activity of ERK, and to further investigate the key biochemical reactions and proteins. The results of the simulation show that an increase in the reaction rate of MAPK/ERK kinase had little effect on ERK activation and the steady-state molecular number. However, a decrease in the reaction rate of MAPK/ERK kinase significantly affected the trigger time of ERK activation and decreased the steady-state molecular number. Together with the biological significance of ERK activity, our findings indicate that the effects of electromagnetic fields are a result of the decrease in the reaction rate of MAPK/ERK kinase, which eventually determines whether these effects cause physical damage or are beneficial in treatment.

Nerve growth factor receptor negates the tumor suppressor p53 as a feedback regulator

Cancer develops and progresses often by inactivating p53. Here, we unveil nerve growth factor receptor (NGFR, p75NTR or CD271) as a novel p53 inactivator. p53 activates NGFR transcription, whereas NGFR inactivates p53 by promoting its MDM2-mediated ubiquitin-dependent proteolysis and by directly binding to its central DNA binding domain and preventing its DNA-binding activity. Inversely, NGFR ablation activates p53, consequently inducing apoptosis, attenuating survival, and reducing clonogenic capability of cancer cells, as well as sensitizing human cancer cells to chemotherapeutic agents that induce p53 and suppressing mouse xenograft tumor growth. NGFR is highly expressed in human glioblastomas, and its gene is often amplified in breast cancers with wild type p53. Altogether, our results demonstrate that cancers hijack NGFR as an oncogenic inhibitor of p53.

DOI:http://dx.doi.org/10.7554/eLife.15099.001

Cancer often develops as a result of alterations to “tumor suppressor” genes within cells. This results in the cells growing and dividing too much, which causes a tumor to form. One of the most important tumor suppressor genes produces a protein called p53, which is lost or mutated in roughly half of all human cancers. In the other half of cancers p53 itself is normal, but is often disabled by proteins that promote tumor growth.

One of the remaining challenges in the field of cancer research is to identify which proteins inhibit p53 directly. Identifying these proteins would help clarify why many human cancers, such as some brain cancers, breast and skin cancers, often maintain a normal form of the p53 tumor suppressor protein.

Zhou et al. now provide evidence that shows that a protein called nerve growth factor receptor (NGFR) is one such protein. NGFR was known to be important for the healthy development of the brain and nervous system. Unexpectedly, however, Zhou et al. found that NGFR binds directly to p53 and disables it in several types of human cancer cells. This finding is likely to be important because NGFR is produced in abnormally high amounts in several human cancer types, including skin, breast, bone and some brain cancers.

Reducing the levels of NGFR in cancer cells caused the cells to become more sensitive to some anti-cancer drugs. Overall, the results presented by Zhou et al. suggest that developing new drugs that target NGFR could produce new treatments for human cancers that have a normal form of the gene that produces p53. More experiments are also needed to find out whether NGFR has other ways of promoting the development of cancerous tumors.

DOI:http://dx.doi.org/10.7554/eLife.15099.002

Comparison of the heart failure risk stratification performance of the CKD-EPI equation and the MDRD equation for estimated glomerular filtration rate in patients with Type 2 diabetes

AIMS

To investigate the risk prediction and the risk stratification performances of the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation and the Modification of Diet in Renal Disease (MDRD) equation for estimated glomerular filtration rate (eGFRCKD - EPI vs. eGFRMDRD ) on heart failure in patients with Type 2 diabetes.

METHODS

The study cohort included 12 258 White and 16 886 African American low-income patients with Type 2 diabetes who were 30-90 years old at baseline. Heart failure risk according to different eGFRCKD - EPI and eGFRMDRD categories was prospectively assessed.

RESULTS

During a mean follow-up of 6.5 years, 5043 incident heart failure cases were identified. Multivariable-adjusted hazard ratios (HRs) of heart failure associated with the eGFRCKD - EPI categories [≥ 90 (reference group), 75-89, 60-74, 30-59 and < 30 ml/min/1.73 m(2) ] were 1.00, 1.11, 1.31, 1.75 and 2.93 (Ptrend < 0.001) for African American patients, and 1.00, 1.11, 1.08, 1.59 and 2.92 (Ptrend < 0.001) for White patients, respectively. The model with eGFRCKD - EPI and the other risk factors had significantly higher Harrell's C than the model with eGFRMDRD and other risk factors. Patients reclassified downward from eGFRMDRD 60-74 to eGFRCKD - EPI 30-59 and from eGFRMDRD 30-59 to eGFRCKD - EPI < 30 ml/min/1.73 m(2) showed higher heart failure risk than those who were not reclassified.

CONCLUSIONS

Impaired kidney function (i.e. GFR < 60 ml/min/1.73 m(2) ), and even mildly decreased GFR (60-74 ml/min/1.73 m(2) ) estimated by both equations is associated with an increased risk of heart failure. Compared with GFR estimated using the MDRD equation, GFR estimated using the CKD-EPI equation added more predictive power to the model with the other risk factors. Also, eGFRCKD - EPI provided more accurate heart failure risk stratification than eGFRMDRD .

Leptin changes differentiation fate and induces senescence in chondrogenic progenitor cells

Body weight is a component of the mechanical theory of OA (osteoarthritis) pathogenesis. Obesity was also found to be a risk factor for digital OA involving non-weight-bearing joints, which suggested that metabolism influences the occurrence and progression of OA. The metabolic origin of OA has been partially attributed to the involvement of adipokines, such as leptin, the levels of which are significantly and positively correlated with cartilage degeneration in OA patients. However, the mechanisms by which leptin-induced cartilage degeneration occurs are poorly understood. The discovery of chondrogenic progenitor cells (CPCs) opened up new opportunities for investigation. Investigating the effects of leptin on differentiation and proliferation in CPCs would increase our understanding of the roles played by leptin in the aetiology and development of OA. Here, CPCs were harvested using single-cell sorting from rat cartilage tissues to obtain mesenchymal stem-like cells, which possess clonogenicity, proliferation and stemness. High doses of leptin decreased the ability of the CPCs to migrate, inhibited their chondrogenic potential and increased their osteogenic potential, suggesting that leptin changes differentiation fates in CPCs. High doses of leptin induced cell cycle arrest and senescence in CPCs by activating the p53/p21 pathway and inhibiting the Sirt1 pathway. Inhibiting the Sirt1 pathway accelerated cartilage senescence in knockout (KO) mice. Activating the leptin pathway induced higher Ob-Rb expression and was significantly correlated with cartilage degeneration (lower levels of Coll-2) and tissue senescence (higher levels of p53/p21 and lower levels of Sirt1) in OA patients, suggesting that leptin-induced CPCs senescence contributes to the development of OA. Taken together, our results reveal new links between obesity and cartilage damage that are induced by leptin-mediated effects on cell behaviour and senescence.

Influence of Dipole Orientation on Solution Properties of Polyzwitterions

We have studied the influence of segmental dipole orientation on the solution properties of polyzwitterions using dynamic and static light scattering of poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC), n-butyl-substituted choline phosphate polymers (PMBP), and their diblock (PMPC-b-PMBP) copolymers in solutions of different salt concentration. We find that these three structures exhibit dramatically different aggregation behaviors. For the conditions in our study, PMPC is a swollen excluded-volume chain without significant presence of dipolar correlations as evident from the lack of sensitivity to the ionic strength of the solution. In contrast, PMBP self-assembles into finite-sized structures in solution, which are stabilized by electrostatic dipole-dipole interactions. Evidence of these interactions is also present in the diblock polymer, PMPB-b-PMPC, which self-assembles into two distinct, stable aggregates in addition to unaggregated chains. These results contribute to the breadth of understanding of polyzwitterions in solution and provide a platform for future simulation and experimental explorations.

Manipulation of a neutral and nonpolar nanoparticle in water using a nonuniform electric field

The manipulation of nanoparticles in water is of essential importance in chemical physics, nanotechnology, medical technology, and biotechnology applications. Generally, a particle with net charges or charge polarity can be driven by an electric field. However, many practical particles only have weak and even negligible charge and polarity, which hinders the electric field to exert a force large enough to drive these nanoparticles directly. Here, we use molecular dynamics simulations to show that a neutral and nonpolar nanoparticle in liquid water can be driven directionally by an external electric field. The directed motion benefits from a nonuniform water environment produced by a nonuniform external electric field, since lower water energies exist under a higher intensity electric field. The nanoparticle spontaneously moves toward locations with a weaker electric field intensity to minimize the energy of the whole system. Considering that the distance between adjacent regions of nonuniform field intensity can reach the micrometer scale, this finding provides a new mechanism of manipulating nanoparticles from the nanoscale to the microscale.