Mutation update and long-term outcome after treatment with active vitamin D3 in Chinese patients with pseudovitamin D-deficiency rickets (PDDR)

Pseudovitamin D-deficiency rickets is a rare disease which is caused by CYP27B1. In this study, we identified 9 mutations in 7 PDDR patients. In addition, we observed the response to long-term treatment of calcitriol in 15 Chinese patients with PDDR, which showed that the biochemical abnormalities had been corrected satisfactorily after 1-year treatment.

INTRODUCTION

Pseudovitamin D-deficiency rickets is a rare autosomal recessive disorder resulting from a defect in 25-hydroxyvitamin D 1α-hydroxylase, which is encoded by CYP27B1. The purpose of this study was to identify the CYP27B1 mutations and investigate the response to long-term treatment of calcitriol in Chinese patients with PDDR.

METHODS

We investigated CYP27B1 mutations in seven individuals from six separate families. To investigate the response to long-term (13 years) treatment with calcitriol in PDDR patients, we additionally collected clinical data of eight families from our previous report and analyzed their biochemical parameter and radiographic changes during the treatment.

RESULTS

Nine different mutations were identified: two novel missense mutations (G194R, R259L), three novel and one reported deletion mutations (c1442delA, c1504delA, c311-321del, and c. 48-60del), two novel nonsense mutations (c.85G>T, c.580G>T), and a reported insertion mutation (c1325-1332insCCCACCC). The statistical analysis revealed that parathyroid hormone (PTH) and ALP significantly decreased after 6-month and 1-year treatment with calcitriol respectively. Urine calcium was measured in all the patients without kidney stones being documented. After 6-year treatment, the radiographic abnormalities had also been improved. Two patients who had reached their final height are both with short stature (height Z-score below - 2.0).

CONCLUSIONS

We identified seven novel mutations of CYP27B1 gene in seven Chinese PDDR families. Our findings revealed after 1-year treatment of active vitamin D₃, PTH and ALP significantly decreased. The correction of the biochemical abnormalities had not improved the final height satisfactorily.

KIR2DL4-HLAG interaction at human NK cell-oligodendrocyte interfaces regulates IFN-γ-mediated effects

Interactions between germline-encoded natural killer (NK) cell receptors and their respective ligands on tumorigenic or virus-infected cells determine NK cell cytotoxic activity and/or cytokine secretion. NK cell cytokine responses can be augmented in and can potentially contribute to multiple sclerosis (MS), an inflammatory disease of the central nervous system focused upon the oligodendrocytes (OLs). To investigate mechanisms by which NK cells may contribute to MS pathogenesis, we developed an in vitro human model of OL-NK cell interaction. We found that activated, but not resting human NK cells form conjugates with, and mediate cytotoxicity against, human oligodendrocytes. NK cells, when in conjugate with OLs, rapidly synthesize and polarize IFN-γ toward the OLs. IFN-γ  is capable of reducing myelin oligodendrocyte and myelin associated glycoproteins (MOG and MAG) content. This activity is independent of MHC class-I mediated inhibition via KIR2DL1, but dependent upon the interaction between NK cell-expressed KIR2DL4 and its oligodendrocyte-expressed ligand, HLA-G. NK cells from patients with MS express higher levels of IFN-γ following conjugation to OLs, more actively promote in vitro reduction of MOG and MAG and have higher frequencies of the KIR2DL4 positive population. These data collectively suggest a mechanism by which NK cells can promote pathogenic effects upon OLs.

[Association between platelet-to-lymphocyte ratio and neutrophil-to-lymphocyte ratio with disease activity in Takayasu arteritis patients]

Objective: To explore the relation between platelet-to-lymphocyte ratio (PLR) or neutrophil-to-lymphocyte ratio (NLR) with disease activity in Takayasu arteritis (TA) patients. Methods: Present retrospective study involved 289 patients with TA, who were hospitalized in our department between January 2010 and October 2017, and 280 age and gender matched healthy controls,who underwent thealth examination in our health examination center during the same period (control group). TA patients were further divided into active and inactive groups (180 and 109 cases respectively) according to Kerr scores. The clinical data were compared between groups. Pearson correlation analysis was used to evaluate the relationship between PLR or NLR and disease activity (Kerr score or C-reactive protein or erythrocyte sedimentation rate). Receiver operating characteristic (ROC) curve was employed to judge the cut-off value of disease activity for TA patients. Results: PLR and NLR were significantly higher in TA group than in control group(137.33 (97.38, 193.37) vs. 120.55 (96.86, 144.60) and 2.38 (1.76, 3.57) vs. 1.66 (1.35, 2.08) , respectively, all P<0.001). PLR and NLR were significantly higher in active TA group than in inactive TA group (163.43 (123.64, 224.15) vs. 110.53 (84.22, 147.24) and 2.59 (1.96, 3.94) vs. 1.95 (1.53, 2.86) respectively, all P<0.001). PLR and NLR of active group were significantly decreased after 6 months treatment (164.05 (123.29, 226.29) vs. 104.67 (77.22, 138.43) and 2.58 (1.96, 3.91) vs. 2.15 (1.67, 2.60) respectively, all P<0.001). PLR was positively correlated with Kerr score (r=0.439, P<0.001), C-reactive protein (r=0.328, P<0.001) and erythrocyte sedimentation rate (r=0.410, P<0.001). NLR also exhibited a positive relationship with Kerr score (r=0.235, P<0.001), C-reactive protein (r=0.169, P=0.005) and erythrocyte sedimentation rate (r=0.123, P=0.037). A PLR level of 176.709 was shown to be the best predictive cut-off value for TA disease activity (sensitivity 44.6%, specificity 93.0%, and area under the curve=0.766).A NLR level of 2.128 was shown to be the best predictive cut-off value for TA disease activity (sensitivity 70.9%, specificity 47.7%, and area under the curve=0.691). Conclusion: PLR and NLR are useful markers for predicting disease activity of TA patients.

Hemoglobin A1c predicts hemorrhagic transformation and poor outcomes after acute anterior stroke

BACKGROUND AND PURPOSE

Hemorrhagic transformation (HT) is a major complication of acute ischaemic stroke that is potentially related to clinical deterioration. The objective of this study was to assess whether chronic hyperglycemia is a predictive factor of HT in patients with acute anterior stroke.

METHODS

Patients with acute anterior stroke were included in this study. Hemoglobin A1c (HbA1c) was measured in the morning after hospitalization. HT was detected by computed tomography scans or gradient echo magnetic resonance imaging performed 4 (±2) days after onset. Univariate and multivariate logistic regression analyses were used to assess the risks for HT and short-term outcomes.

RESULTS

Of the 426 patients included, 93 (21.8%) had HT: 61 (14.3%) presented with hemorrhagic infarction and 32 (7.5%) presented with parenchymal hematoma. A total of 54 patients received thrombolytic treatment and 18 (33.3%) were found to have HT. In the multivariate analysis, HbA1c [odds ratio (OR), 1.294; 95% confidence interval (CI), 1.097-1.528], infarction size (OR, 3.358; 95% CI, 1.748-6.449) and thrombolytic therapy (OR, 3.469; 95% CI, 1.757-6.847) were predictors of HT. The predictive effect of HbA1c on HT was still observed in both groups when patients were stratified according to the levels of fasting blood glucose. HbA1c was found to be a predictor of poor outcomes in the multilogistic regression analysis (OR, 1.482; 95% CI, 1.228-1.788).

CONCLUSIONS

Higher HbA1c was independently related to HT and poor neurological outcomes in patients with ischaemic stroke. These findings have significant implications for the treatment of diabetes and glucose management in patients with diabetes mellitus and/or acute ischaemic stroke.

The association between distance to public amenities and cardiovascular risk factors among lower income Singaporeans

Existing evidence on the association between built environment and cardiovascular disease (CVD) risk factors focused on the general population, which may not generalize to higher risk subgroups such as those with lower socio-economic status (SES). We examined the associations between distance to 5 public amenities from residential housing (public polyclinic, subsidized private clinic, healthier eatery, public park and train station) and 12 CVD risk factors (physical inactivity, medical histories and unhealthy dietary habits) among a study sample of low income Singaporeans aged ≥ 40 years (N = 1972). Using data from the Singapore Heart Foundation Health Mapping Exercise 2013–2015, we performed a series of logistic mixed effect regressions, accounting for clustering of respondents in residential blocks and multiple comparisons. Each regression analysis used the minimum distance (in km) between residential housing and each public amenity as an independent continuous variable and a single risk factor as the dependent variable, controlling for demographic characteristics. Increased distance (geographical inaccessibility) to a train station was significantly associated with lower odds of participation in sports whereas greater distance to a subsidized private clinic was associated with lower odds of having high cholesterol diagnosed. Increasing distance to park was positively associated with higher odds of less vegetable and fruits consumption, deep fried food and fast food consumption in the preceding week/month, high BMI at screening and history of diabetes, albeit not achieving statistical significance. Our findings highlighted potential effects of health-promoting amenities on CVD risk factors in urban low-income setting, suggesting gaps for further investigations.

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We examined associations between access to 5 amenities and 12 CVD risk factors.

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Only 2/60 associations were statistically significant.

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Poorer access to train station was associated with lower odds of sports.

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Poorer access to primary care was associated with lower high cholesterol diagnosis.

Setback distances between small biological wastewater treatment systems and drinking water wells against virus contamination in alluvial aquifers

Contamination of groundwater by pathogenic viruses from small biological wastewater treatment system discharges in remote areas is a major concern. To protect drinking water wells against virus contamination, safe setback distances are required between wastewater disposal fields and water supply wells. In this study, setback distances are calculated for alluvial sand and gravel aquifers for different vadose zone and aquifer thicknesses and horizontal groundwater gradients. This study applies to individual households and small settlements (1-20 persons) in decentralized locations without access to receiving surface waters but with the legal obligation of biological wastewater treatment. The calculations are based on Monte Carlo simulations using an analytical model that couples vertical unsaturated and horizontal saturated flow with virus transport. Hydraulic conductivities and water retention curves were selected from reported distribution functions depending on the type of subsurface media. The enteric virus concentration in effluent discharge was calculated based on reported ranges of enteric virus concentration in faeces, virus infectivity, suspension factor, and virus reduction by mechanical-biological wastewater treatment. To meet the risk target of <10^-4infections/person/year, a 12 log₁₀ reduction was required, using a linear dose-response relationship for the total amount of enteric viruses, at very low exposure concentrations. The results of this study suggest that the horizontal setback distances vary widely ranging 39 to 144m in sand aquifers, 66-289m in gravel aquifers and 1-2.5km in coarse gravel aquifers. It also varies for the same aquifers, depending on the thickness of the vadose zones and the groundwater gradient. For vulnerable fast-flow alluvial aquifers like coarse gravels, the calculated setback distances were too large to achieve practically. Therefore, for this category of aquifer, a high level of treatment is recommended before the effluent is discharged to the ground surface.

Role of vitacamphore in improving central pro-inflammatory cytokines following transient global ischemia

Pro-inflammatory cytokines (PICs) including interleukin-1β (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) are responsive to ischemic stress. This process thereby modulates the responsiveness of many cell types under diseased conditions. The current study was to examine the role played by vitacamphore (VCP) in regulating the levels of PICs and protein expression of PIC receptors in the cerebral cortex and hippocampus of rats after cardiac arrest (CA)-induced transient global ischemia. CA was induced by asphyxia followed by cardiopulmonary resuscitation (CPR) in rats. ELISA and Western blot analyses were employed to determine PICs and their receptors in the cortex and hippocampus. Our results show that IL-1β, IL-6 and TNF-α were significantly elevated in the cortex and hippocampus after CA. This was accompanied with increasing of PIC receptors, namely IL-1R, IL-6R and TNFR1. Systemic injection of VCP attenuated amplification of PIC signal pathway in these brain regions. VCP also improved Neurological Severity Score and brain tissue edema in CA rats. Notably, VCP resulted in a significant increase in survival of CA rats as compared with controls. In conclusion, VCP is likely to play a beneficial role in modulating transient global ischemia induced by CA via PIC signal mechanisms.

Evaluation of the PPAR-γ Agonist Pioglitazone in Mild Asthma: A Double-Blind Randomized Controlled Trial

Background

Peroxisome proliferator-activated receptor gamma (PPAR-γ) is a nuclear receptor that modulates inflammation in models of asthma. To determine whether pioglitazone improves measures of asthma control and airway inflammation, we performed a single-center randomized, double-blind, placebo-controlled, parallel-group trial.

Methods

Sixty-eight participants with mild asthma were randomized to 12 weeks pioglitazone (30 mg for 4 weeks, then 45 mg for 8 weeks) or placebo. The primary outcome was the adjusted mean forced expiratory volume in one second (FEV₁) at 12 weeks. The secondary outcomes were mean peak expiratory flow (PEF), scores on the Juniper Asthma Control Questionnaire (ACQ) and Asthma Quality of Life Questionnaire (AQLQ), fractional exhaled nitric oxide (FeNO), bronchial hyperresponsiveness (PD₂₀), induced sputum counts, and sputum supernatant interferon gamma-inducible protein-10 (IP-10), vascular endothelial growth factor (VEGF), monocyte chemotactic protein-1 (MCP-1), and eosinophil cationic protein (ECP) levels. Study recruitment was closed early after considering the European Medicines Agency’s reports of a potential increased risk of bladder cancer with pioglitazone treatment. Fifty-five cases were included in the full analysis (FA) and 52 in the per-protocol (PP) analysis.

Results

There was no difference in the adjusted FEV₁ at 12 weeks (-0.014 L, 95% confidence interval [CI] -0.15 to 0.12, p = 0.84) or in any of the secondary outcomes in the FA. The PP analysis replicated the FA, with the exception of a lower evening PEF in the pioglitazone group (-21 L/min, 95% CI -39 to -4, p = 0.02).

Conclusions

We found no evidence that treatment with 12 weeks of pioglitazone improved asthma control or airway inflammation in mild asthma.

Trial Registration

ClinicalTrials.gov NCT01134835

Variants in mitochondrial tRNA gene may not be associated with thyroid carcinoma

Thyroid cancer is a very common form of endocrine system malignancy. To date, the molecular mechanism underlying thyroid cancer remains poorly understood. Studies of oncocytic tumors have led to a hypothesis which proposes that defects in oxidative phosphorylation (OX- PHOS) may result in a compensatory increase in mitochondrial replication and gene expression. As a result, mitochondrial DNA (mtDNA) mutation analysis has become a useful tool to explore the molecular basis of this disease. Among these mutations, mitochondrial transfer RNAs (mttRNAs) are the hot spots for pathogenic mutations associated with thyroid cancer. However, due to its high mutation rate, the role of mt-tRNA variants in thyroid cancer is still controversial. To address this problem, in this study, we reassessed seven reported mt-tRNA variants: tRNA^Asp G7521A, tRNA^Arg T10411C and T10463C, tRNA^Leu(CUN) A12308G, tRNA^Ile G4292C and C4312T, and tRNA^Ala T5655C, in clinical manifestations of thyroid cancer. We first performed the phylogenetic conservation analysis for these variants; moreover, we used a bioinformatic tool to compare the minimum free energy (G) of mt-tRNA with and without mutations. Most strikingly, none of these variants caused the significant change of the G between the wild-type and the mutant form, suggesting that they may not play an important roles in thyroid cancer. In addition, we screened the frequency of the “pathogenic” A12308G alternation in 300 patients with thyroid cancer and 200 healthy controls. We found that there were five patients and three control subjects carrying this variant. It seemed that the A12308G variant may be a common polymorphism in the human population. Taken together, our study indicated that variants in mt-tRNA genes may not play active roles in patients with thyroid cancer.

[Follistatin-like 1-engineered mesenchymal stem cells prevent myocardial ischemic reperfusion injury]

OBJECTIVE

To investigate the role of follistatin-like protein 1 (FSTL1) on bone marrow mesenchymal stem cells (BM-MSCs)-mediated cardioprotection during myocardial ischemia/reperfusion injury.

METHODS

Rat bone marrow mesenchymal stem cells were isolated by whole bone marrow adherence method in vitro. A total of 60 Wistar rats were randomly divided into 4 groups: control group, ischemic /reperfusion injury (IRI) group, ischemia/reperfusion injury group treated with natural BM-MSCs (IRI+ MSC group), ischemia/reperfusion injury group treated with BM-MSCs which did not contain FSTL1 (IRI+ MSC FSTL1 siRNA group). Survival analysis was used to analyze survival time of rats, besides, expression of FSTL1 was detected by Western blotting. Myocardial pathological changes were detected by Hematoxylin and Eosin (HE) staining. Terminal-deoxynucleoitidyl transferase mediated nick end labeling (TUNEL) and enzyme-linked immunosorbent assay (ELISA) were used to determine the associated biomarkers and apoptosis 7 days after operation.

RESULTS

Compared with IRI group, rats in IRI+ MSC group had a higher survival rate and lived longer. Meanwhile, IRI+ MSC group had higher FSTL1 expression in blood and myocardial tissues than IRI group. Control group showed significantly lower apoptosis rate of myocardial cells[(1.4±0.1)% vs (29.8±4.5)%, P<0.05], less histological changes and infarction areas (0 vs 24.48±4.27, P<0.05) than IRI group. Compared with IRI group, IRI+ MSC group had an improvement of apoptosis rate[(4.2±0.3)% vs (29.8±4.5)%, P<0.05], less histological injury and infarction areas (15.12±3.82 vs 24.48±4.27, P<0.01). IRI+ MSC group had lower expression of LDH, MDA, CK and higher expression of SOD than IRI group (P<0.05). However, IRI+ MSC FSTL1 siRNA group showed weaker protection of myocardial cells than IRI+ MSC group after knockdown of FSTL1 (P<0.05).

CONCLUSION

FSTL1, which was secreted by BM-MSCs, plays a protective role in myocardial IRI.

Rotavirus infection and histo-blood group antigens in the children hospitalized with diarrhoea in China

To explore the association between rotavirus (RV) infection and histo-blood group antigens (HBGAs), a cross-sectional study was conducted in children hospitalized with diarrhoea in China from November 2014 to February 2015. In total, 424 sets of stool, saliva and buccal cell samples were collected. For the 125 RV-negative samples, 92% (104/125) were secretors/partial secretors, 8% (10/125) were non-secretors. Among the 299 RV-positive samples, 277 were P[8] and 22 were P[4]. All P[4] and P[8] positive individuals were secretors/partial secretors except for one P[8] (0.3%, 1/299), which was a non-secretor. These findings indicate that P[8] and P[4] RVs preferably infect secretors/partial secretors (p <0.001).

Mitochondrial ND3 G10398A mutation: a biomarker for breast cancer

Mitochondrial DNA mutations have been found to play important roles in carcinogenesis. The most common G10398A mutation, a non-conservative amino acid substitution from Thr to Ala, seems to be involved in the tumorigenesis of breast cancer. Results from studies concerning this mutation remain inconclusive. In the current study, we first took clinical and molecular datasets from case-control studies to determine the association between the G10398A mutation and breast cancer. We further used the Phylotree to determine the haplogroups of this mutation. The frequencies of this mutation in 500 unrelated healthy controls were also screened. We found that this mutation is very common in the human population, and may be a polymorph.

MiR-26b modulates insulin sensitivity in adipocytes by interrupting the PTEN/PI3K/AKT pathway

BACKGROUND

MicroRNAs (miRNAs) have emerged as epigenetic regulators of metabolism and energy homeostasis. There is a growing body of evidence pointing to miRNAs that have important regulatory roles in insulin sensitivity.

OBJECTIVE

The aim of this work was to explore the expression and mechanism of action of miR-26b in obesity-related insulin resistance (IR) in adipocytes.

METHODS

Quantitative real-time PCR was performed to determine miR-26b expression in obese rodent models, human obesity subjects and insulin-resistant adipocytes. We analysed the roles of miR-26b overexpression and inhibition on glucose uptake in adipocytes. Western blotting was used to detect the levels of protein molecules involved in the phosphoinositide-3-kinase (PI3K) pathway. Bioinformatics and the Dual Luciferase Assay were used to identify the target gene of miR-26b. We assessed the regulatory roles of miR-26b on the phosphatase and tensin homologue (PTEN)/PI3K/AKT pathway and the relationship between miR-26b and the metabolism of human obese subjects.

RESULTS

Levels of miR-26b are reduced in visceral adipose tissue (VAT) in obese rodent models, human obesity and insulin-resistant adipocytes. MiR-26b promotes insulin-stimulated glucose uptake and increases insulin-stimulated glucose transporter type 4 translocation to the plasma membrane in human mature adipocytes. MiR-26b modulates insulin-stimulated AKT activation via inhibition of its target gene, PTEN, and significantly increases insulin sensitivity via the PTEN/PI3K/AKT pathway. The expression level of miR-26b negatively correlates with increasing body mass index and homeostasis model assessment for IR in human obese subjects.

CONCLUSION

Decreased miR-26b expression in VAT may be involved in obesity-related IR by interrupting the PTEN/PI3K/AKT pathway.

A polymorphism in melanoma differentiation-associated gene 5 may be a risk factor for enterovirus 71 infection

Enterovirus 71 (EV71) infection has a wide variety of clinical manifestations, from no symptoms to fatal disease. Host immune response may be a determinant of disease severity. We investigated the association of polymorphisms in three pattern recognition receptor (PRR) genes-toll-like receptor 3 (TLR3) (rs3775291), retinoic acid-inducible gene I (RIG-I) (rs10813831) and melanoma differentiation-associated gene 5 (MDA5) (rs1990760)-with the severity of EV71 infection. Polymorphisms of candidate genes in 87 EV71-infected patients and 57 asymptomatic controls were detected. Binary logistic regression analysis revealed statistically significant differences in polymorphism of MDA5 (rs1990760) between patients with severe EV71 infection and asymptomatic controls in an additive model (OR 0.424, 95% CI 0.213-0.845, p 0.015) and a dominant model (OR 0.256, 95% CI 0.103-0.635, p 0.003). Polymorphism of MDA5 (rs1990760) (OR 0.399, 95% CI 0.199-0.798, p 0.009) was found to be associated with the severity of EV71 infection with the analysis of ordinal logistic regression. These results indicated the association between MDA5 (rs1990760) polymorphism and an increased risk of a severe EV71 infection in Chinese children, which offers potential for investigating the innate immune mechanism of EV71 infection and identifying at-risk infants, for whom a preventive strategy may reduce the severity of EV71 infection.

Engineered materials for all-optical helicity-dependent magnetic switching

The possibility of manipulating magnetic systems without applied magnetic fields have attracted growing attention over the past fifteen years. The low-power manipulation of the magnetization, preferably at ultrashort timescales, has become a fundamental challenge with implications for future magnetic information memory and storage technologies. Here we explore the optical manipulation of the magnetization in engineered magnetic materials. We demonstrate that all-optical helicity-dependent switching (AO-HDS) can be observed not only in selected rare earth-transition metal (RE-TM) alloy films but also in a much broader variety of materials, including RE-TM alloys, multilayers and heterostructures. We further show that RE-free Co-Ir-based synthetic ferrimagnetic heterostructures designed to mimic the magnetic properties of RE-TM alloys also exhibit AO-HDS. These results challenge present theories of AO-HDS and provide a pathway to engineering materials for future applications based on all-optical control of magnetic order.