ROS-responsive drug-releasing injectable microgels for ameliorating myocardial infarction

Despite of the recent advances in regulatory T cell (Treg) therapy, a limited number of available cells and specificity at the desired tissue site have severely compromised their efficacy. Herein, an injectable drug-releasing (MTK-TK-drug) microgel system in response to in situ stimulation by reactive oxygen species (ROS) was constructed with a coaxial capillary microfluidic system and UV curing. The spherical microgels with a size of 150 μm were obtained. The MTK-TK-drug microgels efficiently converted the pro-inflammatory Th17 cells into anti-inflammatory regulatory T cells (Treg) cells in vitro, and the ROS-scavenging materials synergistically enhanced the effect by modulating the inflammation microenvironment. Thus, the microgels significantly reduced cardiomyocyte apoptosis and decreased the inflammatory response in the early stages of post-myocardial infarction (MI) in vivo, thereby reducing fibrosis, promoting vascularization, and preserving cardiac function. Overall, our results indicate that the MTK-TK-drug microgels can attenuate the inflammatory response and improve MI therapeutic effects in vivo.

Hypoxia and Matrix Metalloproteinase 13-Responsive Hydrogel Microspheres Alleviate Osteoarthritis Progression In Vivo

The occurrence of osteoarthritis (OA) is highly associated with the inflammatory hypoxic microenvironment. Yet currently no attention has been paid to fabricating hypoxia-responsive platforms for OA treatment. Herein, an injectable hydrogel microsphere system (HAM-SA@HCQ) focusing on the hypoxic inflamed joint is prepared with methacrylate-modified sulfonated azocalix[4]arene (SAC4A-MA), methacrylated hyaluronic acid (HA-MA), and dithiol-terminated matrix metalloproteinase 13 (MMP-13) sensitive peptide via a microfluidic device and photo crosslinking technique, followed by encapsulation of the anti-inflammatory drug hydroxychloroquine (HCQ) through host-guest interaction. Owing to the hydrophobic deep cavity, phenolic units, and azo bonds of SAC4A-MA, the hydrogel microspheres show strong drug loading capacity, prominent reactive oxygen species (ROS) scavenging capability, and specific hypoxia-responsive drug release ability. In the OA tissue microenvironment, the hydrogel microspheres undergo degradation by excessive MMP-13 and release HCQ under the hypoxia condition, which synergizes with the ROS-scavenging calixarene to inhibit the inflammatory response of macrophages. After being injected into the OA-inflamed joint, the HAM-SA@HCQ can significantly attenuate the oxidative stress, downregulate the expression of hypoxia-induced factor-1α and inflammatory cytokines, and prevent the cartilage from being destroyed.

In vivo self-assembled shape-memory polyurethane for minimally invasive delivery and therapy

Advanced elastomers are highly in demand for the fabrication of medical devices for minimally invasive surgery (MIS). Herein, a shape memory and self-healing polyurethane (PCLUSe) composed of semi-crystalline poly(ε-caprolactone) (PCL) segments and interchangeable and antioxidative diselenide bonds was designed and synthesized. The excellent shape memory of PCLUSe contributed to the smooth MIS operation, leading to less surgical wounds than in the case of sternotomy. The diselenide bonds of PCLUSe contributed to the rapid self-healing under 405 nm irradiation within 60 s, and the alleviation of tissue oxidation post injury. After being delivered through a 10 mm diameter trocar onto a beating canine heart by MIS, two shape-recovered PCLUSe films self-assembled (self-healing) into a larger single patch (20 × 10 × 0.2 mm3) under the trigger of laser irradiation in situ, which could efficiently overcome the limited-size problem within MIS and meet a larger treatment area. The diselenide bonds in the PCLUSe cardiac patches protected the myocardium under oxidative stress post myocardial infarction (MI), and significantly maintained the cardiac functions.

Intrinsic morphology and spatial distribution of non-structural carbohydrates contribute to drought resistance of two mulberry cultivars

Drought is one of the most adverse environmental stresses limiting plant growth and productivity. However, the underlying mechanisms regarding metabolism of non-structural carbohydrates (NSC) in source and sink organs are still not fully elucidated in woody trees. Saplings of mulberry cv Zhongshen1 and Wubu were subjected to a 15-day progressive drought stress. NSC levels and gene expression involved in NSC metabolism were investigated in roots and leaves. Growth performance and photosynthesis, leaf stomatal morphology, and other physiological parameters were also analysed. Under well-watered conditions, Wubu had a higher R/S, with higher NSC in leaves than in roots; Zhongshen1 had a lower R/S with higher NSC in roots than leaves. Under drought stress, Zhongshen1 showed decreased productivity and increased proline, abscisic acid, ROS content and activity of antioxidant enzymes, while Wubu sustained comparable productivity and photosynthesis. Interestingly, drought resulted in decreased starch and slightly increased soluble sugars in leaves of Wubu, accompanied by notable downregulation of starch-synthesizing genes and upregulation of starch-degrading genes. Similar patterns in NSC levels and relevant gene expression were also observed in roots of Zhongshen1. Concurrently, soluble sugars decreased and starch was unchanged in roots of Wubu and leaves of Zhongshen1. However, gene expression of starch metabolism in roots of Wubu was unaltered, but in leaves of Zhongshen1 starch metabolism was more activated. These findings revealed that intrinsic R/S and spatial distribution of NSC in roots and leaves concomitantly contribute to drought resistance in mulberry.

Chronic thromboembolic pulmonary hypertension global cross-sectional scientific survey (CLARITY) – interim results on the adoption and perception of guidelines

Background

The chronic thromboembolic pulmonary hypertension (CTEPH) global cross-sectional scientific survey (CLARITY) was established to provide insights into current clinical practices and unmet needs in the diagnosis and treatment of CTEPH. The European Society of Cardiology (ESC) plays a leading role in establishing guidelines (GLs) for clinical decision-making in acute pulmonary embolism (PE) and CTEPH. It is of interest to better understand how these GLs affect real-world practice.

Purpose

To assess the adoption and perception of clinical practice GLs among medical specialists working in the fields of cardiology.

Methods

The online survey was developed by an independent committee of 11 international CTEPH experts using the Delphi method and designed to elicit responses regarding disease awareness and management, including follow-up after acute PE and diagnosis of suspected CTEPH. Logic functions were implemented to ensure respondents only viewed questions relevant to their clinical practice. To date, professional members of 17 Scientific Societies and other medical organizations were invited to respond to the survey. For this interim analysis response data were collected from 10.09.2021 to 10.02.2022.

Results

Out of 242 respondents, 107 specialized in cardiology (44%) and 7 specialized in angiology (3%) were included in this interim analysis. Respondents were from Europe (75%, n=85), Asia Pacific (20%, n=23) and the Americas (5%, n=6) and generally had 15–29 (40%, n=45) or 5–14 (37%, n=42) years of working experience. Of the 67 respondents (59%) that did not work in a pulmonary hypertension (PH)/CTEPH expert centre, only 24 (36%) were affiliated with such a centre.

Of respondents involved in acute PE management (n=101) and CTEPH diagnosis (n=87), 87 (86%) and 71 (82%) reported following the 2019 PE ESC/European Respiratory Society (ERS) and 2015 PH ESC/ERS GLs, respectively. Regardless of country, a higher proportion of respondents from Asia Pacific also reported using national GLs for PE (44%, n=10) and CTEPH (52%, n=12) compared to respondents from Europe (15%, n=11; 25%, n=15) and the Americas (25%, n=1; 40%, n=2). Overall, GLs were perceived to facilitate clinical practice (Fig. 1).

Lack of GLs to screen for CTEPH following acute PE was more often reported as a barrier by respondents from Asia Pacific and those working in an expert centre. Low adherence to GLs was reported as a barrier to CTEPH diagnosis by approximately 1/3 of respondents, irrespective of care setting, and in higher proportion among those with more working experience.

Conclusion

Despite the availability of GLs, reported barriers indicate an opportunity for educational activities to improve adoption and adherence to GLs. Observed differences and potential gaps between clinical practice and the GLs warrant further exploration through additional global insights collected by the survey throughout April 2022.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): This survey is sponsored by Actelion Pharmaceuticals Ltd, a Janssen Pharmaceutical Company of Johnson & Johnson

ROS-responsive polymer nanoparticles with enhanced loading of dexamethasone effectively modulate the lung injury microenvironment

The acute lung injury (ALI) is an inflammatory disorder associated with cytokine storm, which activates various reactive oxygen species (ROS) signaling pathways and causes severe complications in patients as currently seen in coronavirus disease 2019 (COVID-19). There is an urgent need for medication of the inflammatory lung environment and effective delivery of drugs to lung to reduce the burden of high doses of medications and attenuate inflammatory cells and pathways. Herein, we prepared dexamethasone-loaded ROS-responsive polymer nanoparticles (PFTU@DEX NPs) by a modified emulsion approach, which achieved high loading content of DEX (11.61 %). DEX was released faster from the PFTU@DEX NPs in a ROS environment, which could scavenge excessive ROS efficiently both in vitro and in vivo. The PFTU NPs and PFTU@DEX NPs showed no hemolysis and cytotoxicity. Free DEX, PFTU NPs and PFTU@DEX NPs shifted M1 macrophages to M2 macrophages in RAW264.7 cells, and showed anti-inflammatory modulation to A549 cells in vitro. The PFTU@DEX NPs treatment significantly reduced the increased total protein concentration in BALF of ALI mice. The delivery of PFTU@DEX NPs decreased the proportion of neutrophils significantly, mitigated the cell apoptosis remarkably compared to the other groups, reduced M1 macrophages and increased M2 macrophages in vivo. Moreover, the PFTU@DEX NPs had the strongest ability to suppress the expression of NLRP3, Caspase1, and IL-1β. Therefore, the PFTU@DEX NPs could efficiently suppress inflammatory cells, ROS signaling pathways, and cell apoptosis to ameliorate LPS-induced ALI. STATEMENT OF SIGNIFICANCE: The acute lung injury (ALI) is an inflammatory disorder associated with cytokine storm, which activates various reactive oxygen species (ROS) signaling pathways and causes severe complications in patients. There is an urgent need for medication of the inflammatory lung environment and effective delivery of drugs to modulate the inflammatory disorder and suppress the expression of ROS and inflammatory cytokines. The inhaled PFTU@DEX NPs prepared through a modified nanoemulsification method suppressed the activation of NLRP3, induced the polarization of macrophage phenotype from M1 to M2, and thereby reduced the neutrophil infiltration, inhibited the release of proteins and inflammatory mediators, and thus decreased the acute lung injury in vivo.

Dexamethasone-loaded ROS-responsive poly(thioketal) nanoparticles suppress inflammation and oxidative stress of acute lung injury

Acute lung injury (ALI) is associated with excessive inflammatory response, leading to acute respiratory distress syndrome (ARDS) without timely treatment. A fewer effective drugs are available currently to treat the ALI/ARDS. Herein, a therapeutic nanoplatform with reactive oxygen species (ROS)-responsiveness was developed for the regulation of inflammation. Dexamethasone acetate (Dex) was encapsulated into poly(thioketal) polymers to form polymeric nanoparticles (NPs) (PTKNPs@Dex). The NPs were composed of poly(1,4-phenyleneacetonedimethylene thioketal) (PPADT) and polythioketal urethane (PTKU), in which the thioketal bonds could be cleaved by the high level of ROS at the ALI site. The PTKNPs@Dex could accumulate in the pulmonary inflammatory sites and release the encapsulated payloads rapidly, leading to the decreased ROS level, less generation of pro-inflammatory cytokines, and reduced lung injury and mortality of mice. RNA sequencing (RNA-seq) analysis showed that the therapeutic efficacy of the NPs was associated with the modulation of many immune and inflammation-linked pathways. These findings provide a newly developed nanoplatform for the efficient treatment of ALI/ARDS.

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A therapeutic nanoplatform with ROS-responsiveness was developed for the regulation of inflammation.

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NPs composed of low Mw of PPADT and high Mw of PTKU were loaded with dexamethasone to obtain a self-adaptive system.

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The Dex-loaded NPs significantly decreased lung inflammation, and reduced lung injury and mortality in vivo.

Inflammation-modulating nanoparticles for pneumonia therapy

Pneumonia is a common but serious infectious disease, and is the sixth leading cause for death. The foreign pathogens such as viruses, fungi, and bacteria establish an inflammation response after interaction with lung, leading to the filling of bronchioles and alveoli with fluids. Although the pharmacotherapies have shown their great effectiveness to combat pathogens, advanced methods are under developing to treat complicated cases such as virus-infection and lung inflammation or acute lung injury (ALI). The inflammation modulation nanoparticles (NPs) can effectively suppress immune cells and inhibit inflammatory molecules in the lung site, and thereby alleviate pneumonia and ALI. In this review, the pathological inflammatory microenvironments in pneumonia, which are instructive for the design of biomaterials therapy, are summarized. The focus is then paid to the inflammation-modulating NPs that modulate the inflammatory cells, cytokines and chemokines, and microenvironments of pneumonia for better therapeutic effects. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Respiratory Disease.

Study of PWR hot leg creep rupture and RCS depressurization strategy during an SBO accident

Preventing the leakage of radioactive materials is important to nuclear safety. During a station blackout accident in pressurized water reactors, the hot leg creep rupture caused by hot leg countercurrent flow occurs before the reactor pressure vessel failure that caused by lower head rupture. The secondary fission products barrier is lost after hot leg creep rupture. An analysis for this phenomenon was done using the Modular Accident Analysis Program version 4.0.4 code. A station blackout accident for CPR1000 is simulated and the occurrence and influence of hot leg creep rupture phenomenon are analyzed in detail. After that, a sensitivity analysis of the opening of different pressurizer pilot-operated relief valves at five minutes after entering severe accident management guideline (before the hot leg creep rupture occurs) is studied. The results show that reactor pressure vessel failure time can be extended by at least 4 h if at least one pilot-operated relief valve is opened and direct containment heating phenomenon can be eliminated if at least two pilot-operated relief valves are opened.

Dimethyl Itaconate-Loaded Nanofibers Rewrite Macrophage Polarization, Reduce Inflammation, and Enhance Repair of Myocardic Infarction

Cellular metabolism plays a major role in the regulation of inflammation. The inflammatory macrophages undergo a wide-range of metabolic rewriting due to the production of significant amount of itaconate metabolite from cis-aconitate in the tricarboxylic acid cycle. This itaconate molecule has been recently described as a promising immunoregulator. However, its function and mode of action on macrophages and tissue repair and regeneration are yet unclear. Herein, the itaconate-derivative dimethyl itaconate (DMI) suppresses the IL-23/IL-17 inflammatory axis-associated genes and promotes antioxidant nuclear factor erythroid 2-related factor 2 target genes. The poly-ε-caprolactone (PCL)/DMI nanofibers implanted in mice initially maintain inflammation by suppressing anti-inflammatory activity and particular inflammation, while at later stage promotes anti-inflammatory activity for an appropriate tissue repair. Furthermore, the PCL/DMI nanofiber patches show an excellent myocardial protection by reducing infarct area and improving ventricular function via time-dependent regulation of myocardium-associated genes. This study unveils potential DMI macrophage modulatory functions in tissue microenvironment and macrophages rewriting for proper tissue repair.

The Dynamic Inflammatory Tissue Microenvironment: Signality and Disease Therapy by Biomaterials

Tissue regeneration is an active multiplex process involving the dynamic inflammatory microenvironment. Under a normal physiological framework, inflammation is necessary for the systematic immunity including tissue repair and regeneration as well as returning to homeostasis. Inflammatory cellular response and metabolic mechanisms play key roles in the well-orchestrated tissue regeneration. If this response is dysregulated, it becomes chronic, which in turn causes progressive fibrosis, improper repair, and autoimmune disorders, ultimately leading to organ failure and death. Therefore, understanding of the complex inflammatory multiple player responses and their cellular metabolisms facilitates the latest insights and brings novel therapeutic methods for early diseases and modern health challenges. This review discusses the recent advances in molecular interactions of immune cells, controlled shift of pro- to anti-inflammation, reparative inflammatory metabolisms in tissue regeneration, controlling of an unfavorable microenvironment, dysregulated inflammatory diseases, and emerging therapeutic strategies including the use of biomaterials, which expand therapeutic views and briefly denote important gaps that are still prevailing.

In situ formation of tetraphenylethylene nano-structures on microgels inside living cells via reduction-responsive self-assembly

Controlling the assembly of synthetic molecules in living systems is of significance for their adaptive applications. However, it is difficult to achieve, especially for composite self-assemblies, due to the complexity and dynamic change of the intracellular environment, and there exist technical difficulties for the direct visualization of organic and polymer self-assemblies. Herein, we demonstrate a novel strategy for the in situ formation of self-assembled micro-nano composite structures in a cell milieu using reduction-responsive microgels (MGs) as a platform. The MGs were prepared by a templating and crosslinking method using a synthetic amphiphlic polymer as the basic material and porous CaCO3 microparticles as the template. The aggregation-induced emission (AIE) tetraphenylethylene moieties and reduction-labile disulfide bonds in the MGs were employed as the self-assembly building blocks and triggering sites for the intracellular self-assembly, respectively. In the presence of reductive agents such as glutathione, nano-spikes were gradually formed on the MGs. After the MGs were internalized by cells, the in situ formation of microgel/nano-spike composite structures was evidenced by the enhanced fluorescence intensity and was further confirmed by direct transmission electron microscopy observation. This work provides an effective strategy to cope with the challenging task of achieving and probing controlled self-assembly in a cell milieu, leading to new insights into investigating biological self-assembly and promoting the development of micro-/nanomaterials by learning from nature.

Antiviral Activity of Nanomaterials against Coronaviruses

One of the challenges facing by world nowadays is the generation of new pathogens that cause public health issues. Coronavirus (CoV) is one of the severe pathogens that possess the RNA (ribonucleic acid) envelop, and extensively infect humans, birds, and other mammals. The novel strain "SARS-CoV-2" (severe acute respiratory syndrome coronavirus-2) causes deadly infection all over the world and presents a pandemic situation nowadays. The SARS-CoV-2 has 40 different strains that create a worrying situation for health authorities. The virus develops serious pneumonia in infected persons and causes severe damage to the lungs. There is no vaccine available for this virus up to present. To cure this type of infections by making vaccines and antiviral drugs is still a major challenge for researchers. Nanotechnology covering a multidisciplinary field may find the solution to this lethal infection. The interaction of nanomaterials and microorganisms is considered as a potential treatment method because the nanomaterials owe unique physicochemical properties. The aim of this review is to present an overview of previous and recent studies of nanomaterials against coronaviruses and to provide possible new strategies for upcoming research using the nanotechnology platform.

Micro- and nanoparticles-based immunoregulation of macrophages for tissue repair and regeneration

The importance of inflammatory tissue microenvironment on the repair and regeneration of tissues and organs has been well recognized. In particular, the phenotypes of macrophages can significantly influence on the processes of tissue repair and remodeling. Among the many types of biomaterials, the particles in the range from nanometers to submicron meters have been extensively studied and applied in tissue engineering and regenerative medicine. They can actively interact with cells in different levels, and show the ability to regulate the polarization of macrophages. In this review, the influence of physicochemical properties such as size, surface charge, chemical components and surface modification of micro-nanoparticles on the immune behavior of macrophages, including endocytosis and phenotype switch, shall be introduced. The important roles of nanoparticles-based immunoregulation of macrophages on the chronic skin wounds regeneration, myocardial repair, liver repair and bone regeneration are discussed.

Adaptive antibacterial biomaterial surfaces and their applications

Bacterial infections on the implant surface may eventually lead to biofilm formation ​and thus threaten the use of implants in body. Despite efficient host immune system, the implant surface can be rapidly occupied by bacteria, resulting in infection persistence, implant failure, and even death of the patients. It is difficult to cope with these problems because bacteria exhibit complex adhesion mechanisms to the implants that vary according to bacterial strains. Different biomaterial coatings have been produced to release antibiotics to kill bacteria. However, antibiotic resistance occurs very frequently. Stimuli-responsive biomaterials have gained much attention in recent years ​but are not effective enough in killing the pathogens because of the complex mechanisms in bacteria. This review is focused on the development of highly efficient and specifically targeted biomaterials that release the antimicrobial agents or respond to bacteria on demands in body. The mechanisms of bacterial adhesion, biofilm formation, and antibiotic resistance are discussed, and the released substances accounting for implant infection are described. Strategies that have been used in past for the eradication of bacterial infections are also discussed. Different types of stimuli can be triggered only upon the existence of bacteria, leading to the release of antibacterial molecules that in turn kill the bacteria. In particular, the toxin-triggered, pH-responsive, and dual stimulus-responsive adaptive antibacterial biomaterials are introduced. Finally, the state of the art in fabrication of dual responsive antibacterial biomaterials and tissue integration in medical implants is discussed.

The nitrone spin trap 5,5-dimethyl-1-pyrroline N-oxide dampens lipopolysaccharide-induced transcriptomic changes in macrophages

OBJECTIVE

M1-like inflammatory phenotype of macrophages plays a critical role in tissue damage in chronic inflammatory diseases. Previously, we found that the nitrone spin trap 5,5-dimethyl-1-pyrroline N-oxide (DMPO) dampens lipopolysaccharide (LPS)-triggered inflammatory priming of RAW 264.7 cells. Herein, we tested whether DMPO by itself can induce changes in macrophage transcriptome, and that these effects may prevent LPS-induced activation of macrophages.

MATERIALS AND METHODS

To test our hypothesis, we performed a transcriptomic and bioinformatics analysis in RAW 264.7 cells incubated with or without LPS, in the presence or in the absence of DMPO.

RESULTS

Functional data analysis showed 79 differentially expressed genes (DEGs) when comparing DMPO vs Control. We used DAVID databases for identifying enriched gene ontology terms and Ingenuity Pathway Analysis for functional analysis. Our data showed that DMPO vs Control comparison of DEGs is related to downregulation immune-system processes among others. Functional analysis indicated that interferon-response factor 7 and toll-like receptor were related (predicted inhibitions) to the observed transcriptomic effects of DMPO. Functional data analyses of the DMPO + LPS vs LPS DEGs were consistent with DMPO-dampening LPS-induced inflammatory transcriptomic profile in RAW 264.7. These changes were confirmed using Nanostring technology.

CONCLUSIONS

Taking together our data, surprisingly, indicate that DMPO by itself affects gene expression related to regulation of immune system and that DMPO dampens LPS-triggered MyD88- and TRIF-dependent signaling pathways. Our research provides critical data for further studies on the possible use of DMPO as a structural platform for the design of novel mechanism-based anti-inflammatory drugs.

Dissection of a circulating CD3+ CD20+ T cell subpopulation in patients with psoriasis

CD3⁺ CD20⁺ T cells are a population of CD3⁺ T cells that express CD20 and identified in healthy donors and autoimmune diseases. However, the nature and role of these cells in patients with psoriasis remain unclear. In this study, we aimed to investigate the level, phenotype, functional and clinical relevance of CD3⁺ CD20⁺ T cells in the peripheral blood of patients with psoriasis. We found that a small subset of CD3⁺ T cells expressed CD20 molecule in the peripheral blood of patients with psoriasis, and their levels were similar to those in healthy donors. Circulating CD3⁺ CD20⁺ T cells in patients with psoriasis were enriched in CD4⁺ cells and displayed an activated effector phenotype, as these cells contained fewer CD45RA⁺ -naive and CCR7⁺ cells with increased activity than those of CD3⁺ T cells lacking CD20. In addition, compared with healthy donors, circulating CD3⁺ CD20⁺ T cells in patients with psoriasis produced more cytokines, interleukin (IL)-17A, tumour necrosis factor (TNF)-α and IL-21, but not IL-4 and IFN-γ. Furthermore, a significantly positive correlation was found between the levels of IL-17A, TNF-α and IL-21-production CD3⁺ CD20⁺ T cells with Psoriasis Area and Severity Index scores. Our findings suggest that CD3⁺ CD20⁺ T cells may play a role in the pathogenesis of psoriasis.

Relationship between inducible NOS single-nucleotide polymorphisms and hypertension in Han Chinese

BACKGROUND

Inducible nitric oxide synthase (iNOS) single-nucleotide polymorphisms have been reported to confer susceptibility to hypertension, but no consensus has been reached. The aim of this study was to investigate the association between iNOS and hypertension in a Chinese population.

METHODS

This was a case-control study including 1172 hypertensive and 1172 control subjects to investigate the association between iNOS and hypertension.

RESULTS

There were significant differences in the distribution of genotype and allele frequencies of rs2779249 and rs2297518 between hypertensive and normotensive subjects. Logistic regression analyses were performed with different genetic models (additive, dominant, recessive) adjusting for confounding risk covariates, including age, sex, body mass index, total cholesterol, triglycerides, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, smoking, drinking, and family history of hypertension. The odds ratio (OR) was 1.27 (1.12, 1.44) in the additive model, 1.31 (1.09, 1.59) in the dominant, and 1.68 (1.28, 2.19) in the recessive model of rs2779249; the OR was 1.26 (1.06, 1.50) in the additive model and 1.46 (1.13, 1.89) in the dominant model of rs2297518.

CONCLUSION

The current study provides evidence that iNOS is strongly associated with hypertension.

Anin situneutron diffraction study of anomalous superelasticity in a strain glass Ni43Fe18Ga27Co12alloy

Superelastic behavior is traditionally related to the martensitic transition with a collective transformation scenario in some shape memory alloys. A kind of quasi-linear superelasticity accompanied by a finite avalanche or confined martensitic transformation was recently found in some alloy systems with strain glass state. Here, anin situneutron diffraction technique was used to study the deformation behavior in an Ni43Fe18Ga27Co12alloy with strain glass state in order to reveal the new intrinsic physical nature of the quasi-linear superelasticity. A significant modulus softening prior to the stress-induced martensitic transformation was observed during compression in the studied alloy, which is similar to the characteristics exhibited in the tweed precursor phenomena prior to temperature-induced martensitic transformation. Moreover, the diffraction peak broadening was further shown during the elastic stage of deformation for both single-crystal and polycrystalline samples, which mainly stems from the short-range fluctuation in the strain field inside each grain based on Williamson–Hall analysis. The authors believe that there exists a spatial heterogeneity in the modulus of the confined martensitic transformation alloy.

Increased circulating follicular helper T cells and activated B cells correlate with disease severity in patients with psoriasis

BACKGROUND

Follicular Helper T (TFH) Cells are a population of recently discovered CD4(+) T cells involved in autoimmune diseases. However, the contribution of TFH cells in patients with psoriasis remains unknown.

OBJECTIVE

We aimed to investigate the levels of TFH cells, B cells and their clinical relevance in patients with psoriasis.

METHODS

Using multi-colour flow cytometry, we detected different subsets of TFH cells and B cells in the peripheral blood of 27 patients with psoriasis and 13 healthy donors. Serum IL-21 levels were measured by ELISA. The relationship between the levels of TFH cells, IL-21, B cells and disease severity were analysed.

RESULTS

Compared with healthy donors, higher levels of circulating CD3(+) CD4(+) CXCR5(+) cells, CD3(+) CD4(+) CXCR5(+) ICOS(+), CD3(+) CD4(+) CXCR5(+) PD-1(+), CD3(+) CD4(+) CXCR5(+) ICOS(+) PD-1(+) TFH cells and CD19(+) IgD(+) CD27(-) naive B, CD19(+) CD86(+) activated B, but lower levels of CD19(+) IgD(+) CD27(+) preswitch and CD19(+) IgD(-) CD27(+) postswitch memory B cells, were observed in patients with psoriasis. In addition, serum IL-21 levels in patients with psoriasis were significantly higher than those in healthy donors, and showed to be positively correlated with the levels of different subsets of TFH cells, and the level of CD19(+) CD86(+) B cells was also correlated with TFH cells and IL-21 levels. Furthermore, a significant correlation was found between the levels of CD3(+) CD4(+) CXCR5(+) ICOS(+) TFH cells, CD3(+) CD4(+) CXCR5(+) ICOS(+) PD-1(+) TFH cells, CD19(+) CD86(+) B cells and IL-21 with Psoriasis Area and Severity Index scores.

CONCLUSION

The levels of TFH cells and activated B cells were increased in the peripheral blood of patients with psoriasis, and positively correlated with disease severity. These results suggest that TFH cells and activated B cells may play a role in the pathogenesis of psoriasis.

Association between loop diuretic use and fracture risk

SUMMARY

Loop diuretic use has been shown to be associated with an increased fracture risk, but the findings have been inconsistent. The present meta-analysis suggests that loop diuretics show a significant positive association with the overall risk of total fractures and, specifically, hip fractures.

INTRODUCTION

Despite being widely used, there is limited, prospective randomized trial evidence regarding the skeletal effects of loop diuretics. Previous observational studies have reported conflicting findings regarding the association between loop diuretic use and the risk of fractures.

METHODS

This meta-analysis of observational studies assessed the association between loop diuretic use and the risk of fractures. The PubMed, EMBASE, and OVID databases were searched for prospective cohort and case-control studies. Relative risks (RR) with 95% confidence intervals (CI) were derived using random-effects models throughout the analysis.

RESULTS

Thirteen studies (4 cohort studies and 9 case-control studies) were included, involving 842,644 participants and 108,247 fracture cases. Compared with non-users, people who had taken loop diuretics had an approximately 15% higher risk of total fractures (95% CI, 1.04-1.26; p<0.01), with high heterogeneity between studies (I2=80.5%; p<0.01). The RR was 1.14 (95% CI, 1.08-1.19) for hip fractures and 0.99 (95% CI, 0.93-1.05) for lower arm or wrist fractures. The RR was 1.05 (95% CI, 1.00-1.11) in prospective cohort studies and 1.22 (95% CI, 1.00-1.44) in case-control studies. There was no evidence of publication bias.

CONCLUSION

The results suggest that loop diuretics show a significant positive association with the overall risk of total fractures and hip fractures.

Coffee, tea, and the risk of hip fracture: a meta-analysis

The present meta-analysis shows no clear association between coffee consumption and the risk of hip fractures. There was a nonlinear association between tea consumption and the risk of hip fracture. Compared to no tea consumption, drinking 1-4 cups of tea daily was associated with a lower risk of hip fracture.

INTRODUCTION

Prospective cohort and case-control studies have suggested that coffee and tea consumption may be associated with the risk of hip fracture; the results have, however, been inconsistent. We conducted a meta-analysis to assess the association between coffee and tea consumption and the risk of hip fracture.

METHODS

We performed systematic searches using MEDLINE, EMBASE, and OVID until February 20, 2013, without limits of language or publication year. Relative risks (RRs) with 95% confidence intervals (CI) were derived using random-effects models throughout all analyses. We conducted categorical, dose-response, heterogeneity, publication bias, and subgroup analyses.

RESULTS

Our study was based on 195,992 individuals with 9,958 cases of hip fractures from 14 studies, including six cohort and eight case-control studies. The pooled RRs of hip fractures for the highest vs. the lowest categories of coffee and tea consumption were 0.94 (95% CI 0.71-1.17) and 0.84 (95% CI 0.66-1.02), respectively. For the dose-response analysis, we found evidence of a nonlinear association between tea consumption and the risk of hip fracture (p(nonlinearity) < 0.01). Compared to no tea consumption, 1-4 cups of tea per day may reduce the risk of hip fracture by 28% (0.72; 95% CI 0.56-0.88 for 1-2 cups/day), 37% (0.63; 95% CI 0.32-0.94 for 2-3 cups/day), and 21% (0.79; 95% CI 0.62-0.96 for 3-4 cups/day).

CONCLUSIONS

We found no significant association between coffee consumption and the risk of hip fracture. A nonlinear association emerged between tea consumption and the risk of hip fracture; individuals drinking 1-4 cups of tea per day exhibited a lower risk of hip fractures than those who drank no tea. The association between 5 daily cups of tea, or more, and hip fracture risk should be investigated.

Neuroimaging methods for adolescent substance use disorder prevention science

Magnetic resonance imaging (MRI) methods safely provide in vivo indicators of cerebral macrostructure, microstructure, and activation that can be examined in relation to substance use disorder (SUD) risks and effects. This article will provide an overview of MRI approaches, including volumetric measures, diffusion tensor imaging, and functional MRI, that have been applied to studies of adolescent neuromaturation in relationship to risk phenotypes and adolescent SUD. To illustrate these applications, examples of research findings will be presented. MRI indicators have demonstrated that neurobiological maturation continues throughout adolescence. MRI research has suggested that variations in neurobiological maturation may contribute to SUD risk, and that substance use adversely influences adolescent brain development. Directly measured neurobiological variables may be viable preventive intervention targets and outcome indicators. Further research is needed to provide definitive findings on neurodevelopmental immaturity as an SUD risk and to determine the directions such observations suggest for advancing prevention science.

Identification of the bacterial biodiversity in koumiss by denaturing gradient gel electrophoresis and species-specific polymerase chain reaction

Bacterial biodiversity in traditional koumiss fermented milk was studied by denaturing gradient gel electrophoresis (DGGE). Target DNA bands were identified according to the reference species ladder, constructed in this study. Comigrating bands present in the DGGE profiles were resolved by species-specific PCR. The results revealed a novel bacterial profile and extensive bacterial biodiversity in koumiss. The dominant lactic acid bacteria included Lactobacillus acidophilus, Lactobacillus helveticus, Lactobacillus fermentum, and Lactobacillus kefiranofaciens. Frequently encountered bacterial species were Enterococcus faecalis, Lactococcus lactis, Lactobacillus paracasei, Lactobacillus kitasatonis, and Lactobacillus kefiri. Leuconostoc mesenteroides, Streptococcus thermophilus, Lactobacillus buchneri, and Lactobacillus jensenii were occasionally found in this product. In addition, L. buchneri, L. jensenii, and L. kitasatonis, which were never previously isolated by culture-dependent methods, were identified for the first time in the Xinjiang koumiss. Furthermore, conventional cultivation was performed by plating samples on M17, de Man-Rogosa-Sharpe, Halligan-Pearce, and Kenner fecal media. The results revealed that lactobacilli were the dominant species in the koumiss ecosystem, which was consistent with the results obtained by the DGGE analysis. This is the first systematic study of the microbial composition in koumiss, and our findings will be helpful in selecting appropriate strains for the manufacture of this product at the industrial level.

Renoprotective effect of rosiglitazone through the suppression of renal intercellular adhesion molecule-1 expression in streptozotocin-induced diabetic rats

OBJECTIVE

To observe the effect of rosiglitazone on serum intercellular adhesion molecule-1 (SICAM-1) level, urinary excretion of ICAM-1, and renal expression of ICAM-1, and investigate its possible renoprotective mechanisms in diabetic rats.

METHOD

Twenty-four Wistar Rats were divided into 3 groups: non-diabetic control rats (group A, no.=8), streptozotocin-induced diabetic rats (group B, no.=8), and diabetic rats treated with rosiglitazone (group C, no.=8). Rats in group C were treated with rosiglitazone (5 mg x kg(-1) x d(-1)) 1 week after the establishment of diabetic model, group A and B were treated with corresponding sodium chloride. Peripheral blood glucose was tested weekly. Glycosylated hemoglobin (HbA1c) and SICAM-1 as well as urinary albumin excretion rate (UAER), urinary retinol binding-protein (URBP) excretion rate, and urinary ICAM-1 (UICAM- 1) excretion rate were tested at the 8th week, and the renal tissues of all rats were obtained for evaluating kidney/body weight ratio, observing pathologic change via electron microscope, and for examining the expression of ICAM-1 mRNA by reverse transcriptase-PCR.

RESULTS

At the 8th week, the blood glucose, HbA1c levels, UAER, URBP excretion rate, kidney/body weight ratio and serum, urinary ICAM-1 levels all increased significantly in group B and group C in comparison with group A; however, the above-mentioned parameters in group C (except the blood glucose and HbA1c levels) were much lower than those in group B. In addition, both SICAM-1 and UICAM-1 were highly correlated with the UAER, URBP level, and kidney/body weight ratio in all rats; renal pathological lesions observed by electron microscope in group C were much lighter than those of group B; compared with group A, the expression of ICAM-1 mRNA was markedly up-regulated in group B and group C, and rosiglitazone was able to decrease the expression of ICAM-1 mRNA in the renal tissue.

CONCLUSION

Rosiglitazone could definitely protect against the renal injury of diabetic rats, which may be partly associated with decreasing the expression of ICAM-1 in the renal tissue, reducing ICAM-1 productions in both serum and urine.

Relation between nuclear envelope and nuclear lamina in nuclear assembly in vitro

Xenopus laevis egg extracts cell-free nuclear assembly system was used as an experimental model to study the process of nuclear lamina assembly in nuclear reconstitution in vitro. The experimental results showed that lamin was involved in the nuclear assembly in vitro. The assembly of nuclear lamina was preceded by the assembly of nuclear matrix, and probably, inner nuclear matrix assembly provided the basis for nuclear lamina assembly. Inhibition of normal assembly of nuclear lamina, by preincubating egg extracts cell-free system with anti-lamin antibodies, resulted in abnormal assembly of nuclear envelope, suggesting that nuclear envelope assembly is closely associated with nuclear lamina assembly.

Composition and structure of nucleolar skeleton (nucleolar matrix) : Actin and fibrillarin are two main protein components of nucleolar skeleton

Purified nucleoli of HeLa cells were treated sequentially with nonionic detergent, nucleic acid enzyme, low salt and high salt. The residual nucleolar structure termed nucleolar skeleton (nucleolar matrix) was shown as a fine network under electron microscope with DGD embedding-unembedding technique. Such structures of BHK-21 cell and mouse liver cell are similar to that of HeLa cell. The protein composition of the nucleolar skeleton of HeLa cells was analyzed. The protein composition of such nucleolar residual shows obvious difference from the compositions of nuclear matrix and chromosome scaffold. The major protein composition of the nucleolar skeleton of HeLa cells contains 6-7 polypeptides. Their molecular weights are about 48, 43, 36 and 33 ku. Further studies show that actin and fibrillarin are two major protein components of nucleolar skeleton of HeLa cells.

Coil-1 of rod domain of NF-L is essential for its assemblyin vivo

Neurofilaments take highly ordered structures composed of parallel mays of 10 nm filaments linked to each other with frequent cross-bridge. It is composed of three components named NF-L, NF-M and NF-H. NF-L is able to form filamentous network alone in Sf9 cells, while M could not. To identify which domain is essential for the assembly of NF-L, two chimera proteins named ML and MML were constructed: ML was composed of the head domain of NF-M and other domains of NF-L; MML was composed of the head and Coil-1 domains of NF-M and Coil-2 and tail domains of NF-L. ML was not only able to form filaments in Sf9 cells, but also co-assemble with NF-M into parallel filamentous bundles. MML could not assemble into filaments. Thus the Coil-1 domain of NF-L was essential for its assembly.

Location identification for indoor instantaneous point contaminant source by probability-based inverse Computational Fluid Dynamics modeling

Indoor pollutions jeopardize human health and welfare and may even cause serious morbidity and mortality under extreme conditions. To effectively control and improve indoor environment quality requires immediate interpretation of pollutant sensor readings and accurate identification of indoor pollution history and source characteristics (e.g. source location and release time). This procedure is complicated by non-uniform and dynamic contaminant indoor dispersion behaviors as well as diverse sensor network distributions. This paper introduces a probability concept based inverse modeling method that is able to identify the source location for an instantaneous point source placed in an enclosed environment with known source release time. The study presents the mathematical models that address three different sensing scenarios: sensors without concentration readings, sensors with spatial concentration readings, and sensors with temporal concentration readings. The paper demonstrates the inverse modeling method and algorithm with two case studies: air pollution in an office space and in an aircraft cabin. The predictions were successfully verified against the forward simulation settings, indicating good capability of the method in finding indoor pollutant sources. The research lays a solid ground for further study of the method for more complicated indoor contamination problems.

PRACTICAL IMPLICATIONS

The method developed can help track indoor contaminant source location with limited sensor outputs. This will ensure an effective and prompt execution of building control strategies and thus achieve a healthy and safe indoor environment. The method can also assist the design of optimal sensor networks.

Inverse modeling methods for indoor airborne pollutant tracking: literature review and fundamentals

Reduction in indoor environment quality calls for effective control and improvement measures. Accurate and prompt identification of contaminant sources ensures that they can be quickly removed and contaminated spaces isolated and cleaned. This paper discusses the use of inverse modeling to identify potential indoor pollutant sources with limited pollutant sensor data. The study reviews various inverse modeling methods for advection-dispersion problems and summarizes the methods into three major categories: forward, backward, and probability inverse modeling methods. The adjoint probability inverse modeling method is indicated as an appropriate model for indoor air pollutant tracking because it can quickly find source location, strength and release time without prior information. The paper introduces the principles of the adjoint probability method and establishes the corresponding adjoint equations for both multi-zone airflow models and computational fluid dynamics (CFD) models. The study proposes a two-stage inverse modeling approach integrating both multi-zone and CFD models, which can provide a rapid estimate of indoor pollution status and history for a whole building. Preliminary case study results indicate that the adjoint probability method is feasible for indoor pollutant inverse modeling.

PRACTICAL IMPLICATIONS

The proposed method can help identify contaminant source characteristics (location and release time) with limited sensor outputs. This will ensure an effective and prompt execution of building management strategies and thus achieve a healthy and safe indoor environment. The method can also help design optimal sensor networks.

Fibrinogen controls human platelet fibronectin internalization and cell-surface retention

BACKGROUND

We recently demonstrated that platelet aggregation occurred in fibrinogen-deficient mice. In these animals, platelet fibronectin (Fn) content was increased 3-5 fold, suggesting that Fn may also be involved in platelet aggregation.

METHODS AND RESULTS

We compared platelet Fn content from a severe hypofibrinogenemic patient (with approximately 0.5% of normal fibrinogen levels) with his parents (heterozygous) and healthy donors. A significant increase in the patient's platelet Fn content was detected by immunoblot, flow cytometry, and immunoelectron microscopy (IEM). To examine the possible contribution of platelet Fn to platelet aggregation, we examined cell-surface Fn expression after thrombin treatment. Unexpectedly, IEM detected only trace amounts of Fn retained on the patient's platelet surface, and flow cytometry indicated that surface Fn was approximately 6-fold lower than that of his parents and tenfold lower than that of healthy donors. An ELISA further confirmed that the patient's platelet Fn was primarily released into the extracellular medium. To test whether retention of surface Fn was due to fibrin formation on the platelet surface, an antifibrin antibody (T2 G1) was employed. Fibrin was detected on platelets from healthy donors and from the father, but was negligible on the patient's platelets. Consistent with these data, when gel-filtered platelets of healthy donors were treated with thrombin receptor activation peptide (SFLLRN-NH(2); no conversion of fibrinogen to fibrin), little surface Fn was detected.

CONCLUSION

Fibrinogen not only competitively inhibits human platelet Fn internalization but also controls platelet-surface Fn retention via fibrin formation. The Fn-fibrin interaction is one possible mechanism to promote Fn interaction with platelets.

TTDN1 is a Plk1-interacting protein involved in maintenance of cell cycle integrity

Polo-like kinase 1 (Plk1) is a highly conserved serine/threonine kinase that plays critical roles in many cell cycle events, especially in mitosis. In the present study, we identified TTDN1 as a potential interacting partner of Plk1 in yeast two-hybrid screens. Sequence analysis indicates that TTDN1 contains a consensus Plk1-binding motif at its C terminus. TTDN1 colocalizes with Plk1 at the centrosome in mitosis and the midbody during cytokinesis. TTDN1 is phosphorylated by Cdk1 in mitosis, and this is required for its interaction with Plk1. Site-directed mutagenesis indicates that TTDN1 is phosphorylated at multiple residues, including Ser93 and Ser104. Mutation of Thr120 of TTDN1 abolishes its interaction with Plk1, suggesting phosphorylation of Thr120 in the consensus Plk1-binding motif is required for its interaction with Plk1. Overexpression of TTDN1 or its knockdown by siRNA causes multi-polar spindles and multiple nuclei, suggesting that TTDN1 plays a role in regulating mitosis and cytokinesis.