Exhaust ventilation in attached garages improves residential indoor air quality

Previous research has shown that indoor benzene levels in homes with attached garages are higher than homes without attached garages. Exhaust ventilation in attached garages is one possible intervention to reduce these concentrations. To evaluate the effectiveness of this intervention, a randomized crossover study was conducted in 33 Ottawa homes in winter 2014. VOCs including benzene, toluene, ethylbenzene, and xylenes, nitrogen dioxide, carbon monoxide, and air exchange rates were measured over four 48-hour periods when a garage exhaust fan was turned on or off. A blower door test conducted in each garage was used to determine the required exhaust fan flow rate to provide a depressurization of 5 Pa in each garage relative to the home. When corrected for ambient concentrations, the fan decreased geometric mean indoor benzene concentrations from 1.04 to 0.40 μg/m³ , or by 62% (P<.05). The garage exhaust fan also significantly reduced outdoor-corrected geometric mean indoor concentrations of other pollutants, including toluene (53%), ethylbenzene (47%), m,p-xylene (45%), o-xylene (43%), and carbon monoxide (23%) (P<.05) while having no impact on the home air exchange rate. This study provides evidence that mechanical exhaust ventilation in attached garages can reduce indoor concentrations of pollutants originating from within attached garages.

[A discussion of the methods for the assessment of chronic hepatitis B-related liver fibrosis regression]

Antiviral therapy could reverse hepatitis B-related liver fibrosis and early-stage cirrhosis. However, the assessment of fibrosis regression remains controversial. As the gold standard for assessment, liver biopsy has its own limitations. In terms of non-invasive assessment, there are many interfering factors for transient elastography and less clinical evidence for the use of serum markers. Therefore, further evidence from clinical studies is still needed to determine the role of non-invasive methods in evaluating fibrosis regression.

Can changing the timing of outdoor air intake reduce indoor concentrations of traffic-related pollutants in schools?

Traffic emissions have been associated with a wide range of adverse health effects. Many schools are situated close to major roads, and as children spend much of their day in school, methods to reduce traffic-related air pollutant concentrations in the school environment are warranted. One promising method to reduce pollutant concentrations in schools is to alter the timing of the ventilation so that high ventilation time periods do not correspond to rush hour traffic. Health Canada, in collaboration with the Ottawa-Carleton District School Board, tested the effect of this action by collecting traffic-related air pollution data from four schools in Ottawa, Canada, during October and November 2013. A baseline and intervention period was assessed in each school. There were statistically significant (P < 0.05) reductions in concentrations of most of the pollutants measured at the two late-start (9 AM start) schools, after adjusting for outdoor concentrations and the absolute indoor-outdoor temperature difference. The intervention at the early-start (8 AM start) schools did not have significant reductions in pollutant concentrations. Based on these findings, changing the timing of the ventilation may be a cost-effective mechanism of reducing traffic-related pollutants in late-start schools located near major roads.

YAP and ERK mediated mechanical strain-induced cell cycle progression through RhoA and cytoskeletal dynamics in rat growth plate chondrocytes

Yes-associated protein (YAP) and extracellular signal-regulated kinase (ERK) have been considered as key regulators in tissue homeostasis, organ development, and tumor formation. However, the roles of YAP and ERK in the mediating strain mechanosensing in the growth plate cartilage have not been determined. In this study, chondrocytes obtained from the growth plate cartilage of 2-week-old Sprague-Dawley rats were subjected to the mechanical strain with different magnitudes and durations at a frequency of 0.5 Hz. We found that YAP and ERK activation in response to mechanical strain was time and magnitude dependent. Pretreatment with a RhoA inhibitor (C3 toxin) or a microfilament cytoskeleton disrupting reagent (cytochalasin D) could suppress their activation. In addition, activated YAP and ERK were able to induce cell cycle progression by up-regulating the expression of cell cycle-related genes. These results shed new light on the function of YAP and ERK in mechanical strain-promoted growth plate development. Our results also provided evidence that RhoA and cytoskeletal dynamics are required for this mechanotransduction. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1121-1129, 2016.

The impact of zinc oxide nanoparticles on phosphorus removal and the microbial community in activated sludge in an SBR

10 and 20 mg L⁻¹ ZnO NPs damaged the integrity of cell membranes and the microbial community and affected phosphorus removal.

Chondrogenic effect of cell-based scaffold of self-assembling peptides/PLGA-PLL loading the hTGFβ3 plasmid DNA

With the application of tissue engineering to tissue regeneration, additional new complexes have been made in response to the challenge of cartilage-injury repair. This study was performed to construct a rat precartilaginous stem cells-based scaffold of self-assembling peptides RADA16-I/PLGA-PLL (poly-L-lysine coated PLGA) as extracellular matrix loading the NLS-TAT as a peptide-based carrier for a plasmid DNA containing hTGFβ3. After composites were cultured for 1, 2, 3 and 4 weeks, respectively, the results showed that the levels of chondrogenic-related gene expression were higher in the experimental group with and hTGFβ3 gene by reverse transcription-polymerase chain reaction, and with higher histochemical and immunohistochemical expression. hTGFβ3 protein expression had increased at 4 weeks based on western blot analysis. The results of this study show that a complex may be a suitable scaffold for cartilage repair and offer a strategy for tissue regeneration through the use of tissue engineering.

Quantitative fibrosis parameters highly predict esophageal-gastro varices in primary biliary cirrhosis

OBJECTIVE

Esophageal-gastro Varices (EGV) may develop in any histological stages of primary biliary cirrhosis (PBC). We aim to establish and validate quantitative fibrosis (qFibrosis) parameters in portal, septal and fibrillar areas as ideal predictors of EGV in PBC patients.

PATIENTS AND METHODS

PBC patients with liver biopsy, esophagogastroscopy and Second Harmonic Generation (SHG)/Two-photon Excited Fluorescence (TPEF) microscopy images were retrospectively enrolled in this study. qFibrosis parameters in portal, septal and fibrillar areas were acquired by computer-assisted SHG/TPEF imaging system. Independent predictor was identified using multivariate logistic regression analysis.

PATIENTS AND METHODS

PBC patients with liver biopsy, esophagogastroscopy and Second Harmonic Generation (SHG)/Two-photon Excited Fluorescence (TPEF) microscopy images were retrospectively enrolled in this study. qFibrosis parameters in portal, septal and fibrillar areas were acquired by computer-assisted SHG/TPEF imaging system. Independent predictor was identified using multivariate logistic regression analysis.

RESULTS

Among the forty-nine PBC patients with qFibrosis images, twenty-nine PBC patients with both esophagogastroscopy data and qFibrosis data were selected out for EGV prognosis analysis and 44.8% (13/29) of them had EGV. The qFibrosis parameters of collagen percentage and number of crosslink in fibrillar area, short/long/thin strings number and length/width of the strings in septa area were associated with EGV (p < 0.05). Multivariate logistic analysis showed that the collagen percentage in fibrillar area ≥ 3.6% was an independent factor to predict EGV (odds ratio 6.9; 95% confidence interval 1.6-27.4). The area under receiver operating characteristic (ROC), diagnostic sensitivity and specificity was 0.9, 100% and 75% respectively.

CONCLUSIONS

Collagen percentage in

CONCLUSIONS

Collagen percentage in the fibrillar area as an independent predictor can highly predict EGV in PBC patients.

Prevalence of Metabolically Healthy Obese and Metabolically Obese but Normal Weight in Adults Worldwide: A Meta-Analysis

The objective of the present study was to summarize the prevalence and influencing factors of metabolically healthy obese (MHO) and metabolically obese but normal weight (MONW) among people ≥ 18 years old in the general population worldwide. We searched for studies of the prevalence of MHO and MONW published in English and Chinese up to October 2013. Pooled prevalence estimates were calculated by a random-effects model according to a Q test. The effects of gender, region, age, sample size, smoking, and alcohol consumption on MHO and MONW were analyzed. Differences between subgroups were assessed by chi-square test. Publication bias was estimated by Egger's test. Studies of MHO and MONW showed heterogeneity (I(2)=99.4% and I(2)=99.7%, respectively). The overall prevalence of MHO and MONW was 7.27% (95% CI 5.92-8.90%) and 19.98% (95% CI 16.54-23.94%), respectively. American populations had the highest MHO prevalence and European populations the highest MONW prevalence. Different patterns of MHO and MONW were observed in the subgroup analysis with respect to gender, age, sample size, smoking, alcohol consumption, and metabolically healthy criteria. The prevalence of both MHO and MONW were affected by gender, region, age, sample size, smoking, alcohol consumption, and metabolically healthy criteria, but studies showed high heterogeneity.

Ipsilateral hippocampal proteomics reveals mitochondrial antioxidative stress impairment in cortical-lesioned chronic mild stressed rats

In this study, a two-dimensional gel-based proteomic approach was applied to profile the protein alterations underlying the significant adverse effects from post-stroke depression (PSD). In view of the close association between left prefrontal cortical dysfunction and PSD, a PSD rat model was constructed through a left anterior cortical lesion followed by chronic mild stress (CMS) for three weeks. Through sucrose preference testing, PSD rats displayed depression-like behavior during the entire CMS period. In contrast, stroke rats displayed depression-like behavior in the first week post-stroke and recovered in the second week post-stroke. To investigate the PSD-induced protein expression changes, ipsilateral hippocampal protein expression in stroke, PSD, and control rats were comparatively analyzed. 46 differential proteins were identified, 22 of which were regulated in opposing directions by stroke and post-stroke stress. The majority of these 22 proteins were involved in neurogenesis, cytoskeletal remodeling, and energy metabolism. Additional proteins were functionally related to mitochondrial antioxidative stress systems. The differential proteins expressed in opposing directions by stroke and post-stroke stress may play a role in self-repair after adult brain lesions, suggesting that stroke induces self-repair mechanisms, while post-stoke stress mitigates them, in the rat hippocampus. Among these differential proteins dysregulated in opposing directions, three mitochondrial proteins involved in mitochondrial antioxidative stress - heat shock 70 kDa protein 9, peroxiredoxin-6, and prohibitin - were validated and may play an important role in stroke-injury self-repair and PSD-induced injury of hippocampal neurons. These findings offer new insight into deciphering the molecular mechanisms underpinning PSD&#039;s adverse effects on stroke recovery.

Chaperone-like protein p32 regulates ULK1 stability and autophagy

Mitophagy mediates clearance of dysfunctional mitochondria, and represents one type of mitochondrial quality control, which is essential for optimal mitochondrial bioenergetics. p32, a chaperone-like protein, is crucial for maintaining mitochondrial membrane potential and oxidative phosphorylation. However, the relationship between p32 and mitochondrial homeostasis has not been addressed. Here, we identified p32 as a key regulator of ULK1 stability by forming complex with ULK1. p32 depletion potentiated K48-linked but impaired K63-linked polyubiquitination of ULK1, leading to proteasome-mediated degradation of ULK1. As a result, silencing p32 profoundly impaired starvation-induced autophagic flux and the clearance of damaged mitochondria caused by mitochondrial uncoupler. Importantly, restoring ULK1 expression in p32-depleted cells rescued autophagy and mitophagy defects. Our findings highlight a cytoprotective role of p32 under starvation conditions by regulating ULK1 stability, and uncover a crucial role of the p32-ULK1-autophagy axis in coordinating stress response, cell survival and mitochondrial homeostasis.Cell Death and Differentiation advance online publication, 24 April 2015; doi:10.1038/cdd.2015.34.

Chaperone-like protein p32 regulates ULK1 stability and autophagy

Mitophagy mediates clearance of dysfunctional mitochondria, and represents one type of mitochondrial quality control, which is essential for optimal mitochondrial bioenergetics. p32, a chaperone-like protein, is crucial for maintaining mitochondrial membrane potential and oxidative phosphorylation. However, the relationship between p32 and mitochondrial homeostasis has not been addressed. Here, we identified p32 as a key regulator of ULK1 stability by forming complex with ULK1. p32 depletion potentiated K48-linked but impaired K63-linked polyubiquitination of ULK1, leading to proteasome-mediated degradation of ULK1. As a result, silencing p32 profoundly impaired starvation-induced autophagic flux and the clearance of damaged mitochondria caused by mitochondrial uncoupler. Importantly, restoring ULK1 expression in p32-depleted cells rescued autophagy and mitophagy defects. Our findings highlight a cytoprotective role of p32 under starvation conditions by regulating ULK1 stability, and uncover a crucial role of the p32-ULK1-autophagy axis in coordinating stress response, cell survival and mitochondrial homeostasis.

Alterations in enhancer of zeste homolog 2, matrix metalloproteinase-2 and tissue inhibitor of metalloproteinase-2 expression are associated with ex vivo and in vitro bone metastasis in renal cell carcinoma

Renal cell carcinoma (RCC) has a high potential for bone metastasis; however, the molecular mechanisms underlying this metastasis have remained to be elucidated. The present study aimed to explore the expression levels of enhancer of zeste homolog 2 (EZH2), matrix metalloproteinase-2 (MMP2) and tissue inhibitor of metalloproteinase-2 (TIMP2) as determinants of RCC-associated bone metastasis. Their expression was evaluated in a newly generated RCC cell subline that has a high potential for bone metastasis, in tissue specimens from metastasized bone tissues from patients with RCC and in RCC tissues without metastasis. A total of 25 RCC tissue specimens without metastasis and 13 RCC tissue specimens with bone metastasis were acquired for immunohistochemical analysis of EZH2, MMP2 and TIMP2 protein expression. The expression levels of EZH2, MMP2 and TIMP2 mRNA and protein were analyzed in the ACHN and ACHN-BO5 cell lines using western blot and reverse transcription polymerase chain reaction (PCR) analyses. Methylation-specific PCR was also used to analyze TIMP2 promoter methylation. EZH2 and MMP2 proteins were found to be expressed at higher levels in tissues from patients where RCC had metastasized to the bone as compared with those in RCC patients without metastasis, whereas there was no significant difference in the expression of TIMP2 protein between the two tissues. Furthermore, the expression of EZH2 protein was correlated with MMP2 expression, but there was no significant correlation between the expression of EZH2 and TIMP2 proteins. The in vitro results using cell lines confirmed the ex vivo findings, indicating that the expression levels of EZH2 and MMP2 protein and mRNA were higher in ACHN-BO5 cells than those in ACHN cells. By contrast, TIMP2 protein and mRNA expression levels were lower in ACHN-BO5 cells than those in the parental ACHN cells. The TIMP2 promoter was highly methylated in ACHN-BO5 cells compared with that in ACHN cells. Upregulation of EZH2, MMP2 and TIMP2 expression was correlated with metastasis of RCC to bone tissues ex vivo and in vitro. Further studies are required in order to elucidate the mechanism underlying the altered expression of these genes.

The impact of zinc oxide nanoparticles on nitrification and the bacterial community in activated sludge in an SBR

20 and 50 mg L⁻¹ of ZnO NPs affect transformation of NH₄⁺–N to NO₂⁻–N and NO₂⁻–N to NO₃⁻–N.

Association analysis of polymorphisms in OAS1 with susceptibility and severity of hand, foot and mouth disease

Hand, foot and mouth disease (HFMD) is a common childhood illness that mainly affects Asian children under the age of 5 years. Human enterovirus 71 (EV71) and coxsackievirus A16 (CA16) are the most common pathogens of HFMD. It is imperative that the susceptible population is screened early and that the severe illness population can be identified via genetic variation detection in children. Four single-nucleotide polymorphisms (SNP) [2'-5'-oligoadenylate synthetase1 (OAS1) rs10774671, selectin P ligand (SELPLG) rs2228315, scavenger receptor class B member 2 (SCARB2) rs41284767 and interleukin 28B (IL28B) rs12979860] were determined by Taqman assays in 333 HFMD samples and 163 control samples. The rs2228315, rs41284767 and rs12979860 polymorphisms did not differ significantly between HFMD patients and the controls, but the prevalence of the rs10774671 polymorphism was significantly different between the control children and children infected with CA16 (GG genotype vs. AA + AG genotype, P < 0.05). Children with the GG genotype were more susceptible to CA16-type HFMD. Furthermore, the rs10774671 genotype distribution was clearly different between children with severe HFMD and those with mild HFMD [P < 0.05, OR 0.240, 95% CI (0.071-0.809)]. HFMD children with the AA+AG genotype were more likely to progress to encephalitis than were those with the GG genotype. Plasma γ-interferon (IFN) expression levels among control children and the mild and severe HFMD children were detected by ELISA. Those with mild HFMD had higher γ-IFN expression levels compared with those with severe HFMD (P < 0.05). In addition, there is a significant correlation between γ-IFN levels and OAS1 rs10774671 SNP, as analysed by linear correlation assay. The GG genotype correlated with higher γ-IFN levels (P < 0.05). In short, the OAS1 rs10774671 SNP GG genotype contributed to CA16 susceptibility and was associated with the development of mild HFMD.

Statins in nervous system-associated diseases: angels or devils?

Statins are commonly prescribed lipid-lowering medications that significantly reduce the risk of cardiovascular events. In addition to their ability to lower cholesterol by affecting the rate-limiting step in cholesterol biosynthesis, statins also have anti-inflammatory, immunomodulatory, antioxidant, antiapoptotic, and antiplatelet effects. Because of these pleiotropic abilities, statins may have some beneficial effects on neurologic diseases, including cerebrovascular disease, neurodegenerative disease, multiple sclerosis, and brain tumors. Although statins are a well-tolerated class of drugs, they also have potential adverse effects (AEs). A growing body of evidence indicates that statins may have potential negative effects on nervous system-associated diseases, including myopathies, peripheral neuropathy, intracerebral hemorrhage (ICH), and other diseases of the central nervous system (e.g., cognitive impairment, depression, sleep disorders, nightmare, and headache). Clinicians, especially neurologists, should be aware of the potential risk of neuropathy in patients who take statins.

Chondrogenic effect of precartilaginous stem cells following NLS-TAT cell penetrating peptide-assisted transfection of eukaryotic hTGFβ3

Cell penetrating peptides (CPPs) are a series of promising carriers for delivering exogenous DNA to living cells. Among them, the combination of the human immunodeficiency virus TAT protein (TAT) with the SV40 large T protein nuclear localization signal (NLS) to form NLS-TAT performs well. In the present study, we took advantage of this new carrier to deliver transforming growth factor-beta 3 (TGFβ3) genes. TGFβ3 was expressed by the pEGFP-N1 vector following transfection of rat precartilaginous stem cells (PSCs), which promoted hTGFβ3 protein self-expression. At 24, 48, 72, and 120 h after transfection, the expression levels of hTGFβ3 were found to be elevated as compared with the control. The expression of hTGFβ3 was found to mediate the chondrogenic effect of PSCs. Thus, we determined the expression of the chondrogenesis-related genes type II collagen, Sox 9, and aggrecan in PSCs at 24, 48, 72, and 120 h after transfection. We found that their transcription and translation was augmented, which indicated a trend of active chondrogenesis in the PSCs. Our results demonstrated that NLS-TAT had the ability to deliver exogenous DNA into rat PSCs and could be actively expressed. This process successfully promoted PSC chondrogenesis. Additionally, PSC, may represent a new type of stem cells, and thus show great potential in regenerative repair following cartilage injury.

An empirical model for gas phase acidity and basicity estimation

Gas phase acidity and basicity estimation models have been developed for acidic and basic functional groups of amino acid side-chains and also for a number of small organic molecules. The acidic functional groups include aliphatic and aromatic alcohol, and aliphatic and aromatic carboxylic acid, and the basic functional groups include aliphatic, aromatic and hetero-aromatic amines, and also pyridino-, pyrazolo- and imidazolo-groupings. The models are described in terms of a linear combination of descriptors that highly influence reactivity at the reaction centres of the functional groups. In order to describe the chemical environments of the deprotonating and protonating sites, atomic descriptors such as the effective atomic electronegativity and effective atomic polarizability of the atoms in the reaction field and the electrostatic potentials at the reaction sites have been introduced. The coefficient of determination (r(2)) of each model is above 0.8, apart from the imidazole model. The models are readily applicable, ranging from simple organic molecules to proteins.

Immunomagnetic indirect positive sorting of precartilaginous stem cells from neonatal rat

To investigate the technique of sorting high-purity precartilaginous stem cells from rat's perichondrium, neonatal rat's perichondrium cells suspensions were incubated with monoclone antibody of anti-fibroblast growth factor receptor-3 (anti-FGFR-3), and the labeled cells were separated from the suspension in the magnetic field by immuno-beads coated with the second antibody. Purity of the sorted neural stem cells was found to be 93.0%-99.0%, with living cells amounting to 80% -85 %. The magnetic cell sorting system could effectively separate precartilaginous stem cells from perichondrium cell suspensions.

Regulation of PTHrP expression by cyclic mechanical strain in postnatal growth plate chondrocytes

Mechanical loading has been widely considered to be a crucial regulatory factor for growth plate development, but the exact mechanisms of this regulation are still not completely understood. In the growth plate, parathyroid hormone-related protein (PTHrP) regulates chondrocyte differentiation and longitudinal growth. Cyclic mechanical strain has been demonstrated to influence growth plate chondrocyte differentiation and metabolism, whereas the relationship between cyclic mechanical strain and PTHrP expression is not clear. The objective of this study was to investigate whether short-term cyclic tensile strain regulates PTHrP expression in postnatal growth plate chondrocytes in vitro and to explore whether the organization of cytoskeletal F-actin microfilaments is involved in this process. To this end, we obtained growth plate chondrocytes from 2-week-old Sprague-Dawley rats and sorted prehypertrophic and hypertrophic chondrocytes using immunomagnetic beads coated with anti-CD200 antibody. The sorted chondrocytes were subjected to cyclic tensile strain of varying magnitude and duration at a frequency of 0.5 Hz. We found that cyclic strain regulates PTHrP expression in a magnitude- and time-dependent manner. Incubation of chondrocytes with cytochalasin D, an actin microfilament-disrupting reagent, blocked the induction of PTHrP expression in response to strain. The results suggest that short-term cyclic tensile strain induces PTHrP expression in postnatal growth plate prehypertrophic and hypertrophic chondrocytes and that PTHrP expression by these chondrocytes may subsequently affect growth plate development. The results also support the idea that the organization of cytoskeletal F-actin microfilaments plays an important role in mechanotransduction.

A randomized double-blind crossover study of indoor air filtration and acute changes in cardiorespiratory health in a First Nations community

Few studies have examined indoor air quality in First Nations communities and its impact on cardiorespiratory health. To address this need, we conducted a crossover study on a First Nations reserve in Manitoba, Canada, including 37 residents in 20 homes. Each home received an electrostatic air filter and a placebo filter for 1 week in random order, and lung function, blood pressure, and endothelial function measures were collected at the beginning and end of each week. Indoor air pollutants were monitored throughout the study period. Indoor PM2.5 decreased substantially during air filter weeks relative to placebo (mean difference: 37 μg/m(3) , 95% CI: 10, 64) but remained approximately five times greater than outdoor concentrations owing to a high prevalence of indoor smoking. On average, air filter use was associated with a 217-ml (95% CI: 23, 410) increase in forced expiratory volume in 1 s, a 7.9-mm Hg (95% CI: -17, 0.82) decrease in systolic blood pressure, and a 4.5-mm Hg (95% CI: -11, 2.4) decrease in diastolic blood pressure. Consistent inverse associations were also observed between indoor PM2.5 and lung function. In general, our findings suggest that reducing indoor PM2.5 may contribute to improved lung function in First Nations communities.

PRACTICAL IMPLICATIONS

Indoor air quality is known to contribute to adverse cardiorespiratory health, but few studies have examined indoor air quality in First Nations communities. Our findings suggest that indoor PM2.5 may contribute to reduced lung function and that portable air filters may help to alleviate these effects by effectively reducing indoor levels of particulate matter.

Telbivudine treatment in chronic hepatitis B: experience from China

Telbivudine, one of the oral anti-hepatitis B virus (HBV) nucleoside analogues, has been used for more than 5 years to treat HBeAg-positive and -negative chronic hepatitis B (CHB) patients. This includes not only global Phase II and III trials, but also Chinese Phase III trials and several real-world clinical practice studies from China. The present review will first focus on 1-, 2- and 3-year data of telbivudine therapy on HBV DNA suppression, alanine aminotransferase (ALT) normalization, hepatitis B e antigen (HBeAg) seroconversion, viral resistance and safety in HBeAg-positive and -negative CHB patients. Second, telbivudine treatment predictors, including HBV DNA undetectability, ALT level and other immune-related markers at 12 and 24 weeks will be summarized to optimize therapy. Besides several retrospective studies, the Chinese EFFORT prospective study adapted from telbivudine virological response at 24 weeks has shown very promising results. Finally, the Chinese experience of using telbivudine in the second and third trimesters of pregnancy to prevent perinatal transmission of HBV infection will be touched on citing the latest studies.