Parity and osteoporotic fracture risk in postmenopausal women: a dose-response meta-analysis of prospective studies

The present dose-response meta-analysis shows linearly decreased hip fracture (HF) risk and nonlinearly decreased osteoporotic fracture (OF) risk associated with increasing number of parity of up to five live births among postmenopausal women.

INTRODUCTION

Epidemiological reports suggest that parity is associated with reduced OF risk among women. However, these findings are controversial. Here, we present a meta-analysis of prospective studies of parity in relation to OF risk.

METHODS

We performed systematic searches using Medline and Embase from January 1, 1966, to December 31, 2014, with limits of language in English and prospective study design. Relative risks (RRs) and confidence intervals (CIs) were derived mainly using random-effects models. Categorical, dose-response, heterogeneity, publication bias, and subgroup analyses were conducted.

RESULTS

We analyzed 10 articles of 19 independent reports from 1966 to 2014, comprising a total of 217,295 participants and 26,525 cases of OF. Compared to nulliparous women, the OF and HF risks of parous women with at least one live birth were reduced by 11 % (95 % confidence interval (CI) 3-19 %; I (2) = 77.1 %, p < 0.001) and 26 % (95 % CI 17-35 %; I (2) = 19.5 %, p = 0.287), respectively. Representative nonlinearly and linearly inverse dose-response associations were found between parity (range of 0-6) and OF risk (p nonlinearity = 0.0163; I (2) = 79.7 %, p < 0.001), and between parity (range of 0-5) and HF risk (p nonlinearity = 0.054; I (2) = 76.5 %, p < 0.001), respectively. The lowest risk reduction for OF of 25 % (95 % CI 16-33 %) was observed for five live births. And, the summary risk reduction for HF was 12 % (95 % CI 9-15 %) for each one increased live birth.

CONCLUSIONS

We found that increasing number of parity is associated with linearly reduced HF risks among women. The association between parity of six or more live births and HF risks should be studied further in future.

Operational Head-on Beam-Beam Compensation with Electron Lenses in the Relativistic Heavy Ion Collider

Head-on beam-beam compensation has been implemented in the Relativistic Heavy Ion Collider in order to increase the luminosity delivered to the experiments. We discuss the principle of combining a lattice for resonance driving term compensation and an electron lens for tune spread compensation. We describe the electron lens technology and its operational use. To date, the implemented compensation scheme approximately doubled the peak and average luminosities.

Baseline characteristics and management of patients with atrial fibrillation/flutter in the emergency department: results of a prospective, multicentre registry in China

BACKGROUND/AIM

There have been several studies of atrial fibrillation (AF) over the past decades; however, data from Chinese patients are scarce. The aim of the study was therefore to describe the patient characteristics, risk profile and management strategies for Chinese AF patients presenting to emergency department (ED).

METHODS

We conducted a prospective, multicentre registry of patients with AF or atrial flutter (AFL) in China. Participants were enrolled at 20 EDs, then data regarding baseline characteristics and treatment in EDs were collected.

RESULTS

Of the 2016 Chinese patients, 1104 (54.8%) were female. Six hundred eighteen (30.7%) had paroxysmal AF, 452 (22.4%) had persistent AF and 945 (46.9%) had permanent AF. The most common comorbidity was hypertension (55.5%), followed by coronary artery disease (41.8%) and heart failure (HF, 37.4%). The prevalence of concomitant cardiovascular risk factors, such as HF and valvular heart disease, increased as AF progressed. Among the patients with non-valvular AF, 110 (12.7%) of those with CHADS2 (congestive HF, hypertension, age of 75 years and greater, diabetes mellitus and history of stroke) ≥2 were prescribed oral anticoagulants (OAC), while 119 (15.6%) of those with CHADS2 <2 received such agents. Among the 324 patients with valvular AF, 134 (41.4%) actually were treated with OAC. The international normalised ratio value was within the target range (2.0-3.0) in 96 patients only (26.4%). Moreover, a total of 16.2% of the patients received ≥1 anti-arrhythmic agents, whereas rate control agents were used more frequently (68.4%).

CONCLUSIONS

According to the present study, the risk profile and management of Chinese patients with AF/AFL differed from that observed in previous studies. The use of OAC inadequately deviate from current guidelines.

Molecular identification of Echinococcus granulosus on the Tibetan Plateau using mitochondrial DNA markers

Cystic echinococcosis (CE) is an important worldwide zoonotic disease that causes large economic losses and human suffering. Echinococcus granulosus, the causative agent of CE, exhibits different genotypes in different locations. In order to identify its genotypes and analyze its genetic structure on the Tibetan Plateau, we collected 72 hydatid cysts from different intermediate hosts and amplified and sequenced their mitochondrial cytochrome c oxidase subunit 2 (cox2) genes. Seventy isolates were identified as the E. granulosus G1 genotype, while two isolates belonged to the G6 genotype. There were 18 haplotypes among the 70 E. granulosus isolates, which exhibited a star-like network pattern and shared a common haplotype (H1). There was little difference between geographical sub-populations. Our results suggest that a recent E. granulosus population expansion occurred on the Tibetan Plateau, suggesting that E. granulosus was introduced into China. This study increases the basic molecular data needed for the molecular diagnosis, epidemiology, prevention, and control of Echinococcus diseases.

Altered mesenchymal niche cells impede generation of normal hematopoietic progenitor cells in leukemic bone marrow

Degeneration of normal hematopoietic cells is a shared feature of malignant diseases in the hematopoietic system. Previous studies have shown the exhaustion of hematopoietic progenitor cells (HPCs) in leukemic marrow, whereas hematopoietic stem cells (HSCs) remain functional upon relocation to non-leukemic marrow. However, the underlying cellular mechanisms, especially the specific niche components that are responsible for the degeneration of HPCs, are unknown. In this study, we focused on murine bone mesenchymal stem cells (MSCs) and their supporting function for normal hematopoietic cells in Notch1-induced acute T-cell lymphocytic leukemia (T-ALL) mice. We demonstrate that the proliferative capability and differentiation potential of T-ALL MSCs were impaired due to accelerated cellular senescence. RNA-seq analysis revealed significant transcriptional alterations in leukemic MSCs. After co-cultured with the MSCs from T-ALL mice, a specific inhibitory effect on HPCs was defined, whereas in vivo repopulating potential of normal HSCs was not compromised. Furthermore, osteoprotegerin was identified as a cytokine to improve the function of T-ALL MSCs and to enhance normal HPC output via the p38/ERK pathway. Therefore, this study reveals a novel cellular mechanism underlying the inhibition of HPC generation in T-ALL. Leukemic MSCs may serve as a cellular target for improving normal hematopoietic regeneration therapeutically.

Integration of Physiologically-Based Pharmacokinetic Modeling into Early Clinical Development: An Investigation of the Pharmacokinetic Nonlinearity

BMS-911543, a promising anticancer agent, exhibited time-dependent and dose-dependent nonlinear pharmacokinetics (PKs) in its first-in-human (FIH) study. Initial physiologically based pharmacokinetic (PBPK) modeling efforts using CYP1A2-mediated clearance kinetics were unsuccessful; however, further model analysis revealed that CYP1A2 time-dependent inhibition (TDI) and perhaps other factors could be keys to the nonlinearity. Subsequent experiments in human liver microsomes showed that the compound was a time-dependent inhibitor of CYP1A2 and were used to determine the enzyme inactivation parameter values. In addition, a rat tissue distribution study was conducted and human plasma samples were profiled to support the refinement of the PBPK model. It was concluded that the interplay between four BMS-911543 properties, namely, low solubility, saturation of the metabolizing enzyme CYP1A2, CYP1A2 TDI, and CYP1A2 induction likely resulted in the time-dependent and dose-dependent nonlinear PKs. The methodology of PBPK model-guided unmasking of compound properties can serve as a general practice for mechanistic understanding of a new compound's disposition.

Serum leptin levels in obese women with and without type 2 diabetes mellitus

AIM

The role of leptin has been more clear in the endocrinology area after the discovery of its secretion from the adipose tissue. The aim of the study is to investigate the leptin levels in obese women in whom type 2 diabetes mellitus were present or absent.

METHODS

Fifty obese women with type 2 diabetes mellitus (group 1) and another 50 obese women without type 2 diabetes mellitus (group 2) were enrolled in the study. In both groups the body mass index (BMI), waist circumference, and waist-to-hip ratio were measured. Leptin, HbA1c, creatinine and the lipid profile were assessed.

RESULTS

Leptin was found to be statistically significantly lower in group 1 than in group 2 (38.79 ± 18.75 ng/ml versus 52.45 ± 16.89 ng/ml, respectively; P=0.017). In group 1, correlation of leptin was moderate with creatinine and high-density lipoprotein-cholesterol (r=0.46, p = 0.039 versus r=0.47, p=0.028, respectively), whereas triglyceride had a negative correlation (r= -0.35, p=0.047). In group 2, the only significant correlation with leptin was BMI (r=0.41, p=0.02). Leptin was also significantly lower in 24 patients with poorly controlled diabetes mellitus patients than in 26 well-controlled diabetics (35.45 ± 14.92 ng/ml versus 45.72 ± 16.69 ng/ml, respectively; p=0.029).

CONCLUSION

Since leptin is lower in obese women with diabetes than without diabetes and additionally it is even lower in the poorly controlled diabetes subgroup, we think that further studies are required to make clear the issue for lower leptin levels, whether it is a reason or an outcome.

Hypoxia-inducible factor-1alpha: molecular-targeted therapy for hepatocellular carcinoma

Hypoxia-inducible factor (HIF)-1α is over-expressed in hepatocellular carcinoma (HCC) and degraded by ubiquitin-proteasome pathways under normoxic conditions. Hepatocyte hypoxia enhances proliferation, angiogenesis, metastasis, chemoresistance, and radioresistance of HCC. The importance role of HIF-1α expression in HCC may improve the prognostic and therapeutic technique. This article reviews the HIF-1α expression and its gene during the rat HCC development, the level of HIF-1α expression in HCC patients, and the effect of silencing HIF-1α gene by miRNA on inhibition of HepG2 cell proliferation.