Prevalence and incidence of Alzheimer's disease in Europe: A meta-analysis

BACKGROUND

A disease of unknown aetiology, Alzheimer's disease (AD) is the most common type of dementia. As the elderly population grows worldwide, the number of patients with AD also increases rapidly. The aim of this meta-analysis is to evaluate the prevalence and incidence of AD in Europe.

METHODOLOGY

We conducted a literature search on Medline, Scopus, and CINAHL Complete using the keywords «Alzheimer», «Alzheimer's disease», and «AD» combined with «prevalence», «incidence», and «epidemiology». A Bayesian random effects model with 95% credible intervals was used. The I² statistic was applied to assess heterogeneity.

RESULTS

The prevalence of Alzheimer's disease in Europe was estimated at 5.05% (95% CI, 4.73-5.39). The prevalence in men was 3.31% (95% CI, 2.85-3.80) and in women, 7.13% (95% CI, 6.56-7.72), and increased with age. The incidence of Alzheimer's disease in Europe was 11.08 per 1000 person-years (95% CI, 10.30-11.89). Broken down by sex, it was 7.02 per 1000 person-years (95% CI, 6.06-8.05) in men and 13.25 per 1000 person-years (95% CI, 12.05-14.51) in women; again these rates increased with age.

CONCLUSIONS

The results of our meta-analysis allow a better grasp of the impact of this disease in Europe.

Antigen receptor signaling induces MAP kinase-mediated phosphorylation and degradation of the BCL-6 transcription factor

The bcl-6 proto-oncogene encodes a POZ/zinc finger transcriptional repressor expressed in germinal center (GC) B and T cells and required for GC formation and antibody affinity maturation. Deregulation of bcl-6 expression by chromosomal rearrangements and point mutations of the bcl-6 promoter region are implicated in the pathogenesis of B-cell lymphoma. The signals regulating bcl-6 expression are not known. Here we show that antigen receptor activation leads to BCL-6 phosphorylation by mitogen-activated protein kinase (MAPK). Phosphorylation, in turn, targets BCL-6 for rapid degradation by the ubiquitin/proteasome pathway. These findings indicate that BCL-6 expression is directly controlled by the antigen receptor via MAPK activation. This signaling pathway may be crucial for the control of B-cell differentiation and antibody response and has implications for the regulation of other POZ/zinc finger transcription factors in other tissues.

Chromosomal translocations cause deregulated BCL6 expression by promoter substitution in B cell lymphoma

The BCL6 gene codes for a zinc-finger transcription factor and is involved in chromosomal rearrangements in 30-40% of diffuse large-cell lymphoma (DLCL). These rearrangements cluster within the 5' regulatory region of BCL6 spanning its first non-coding exon. To determine the functional consequences of these alterations, we have analyzed the structure of the rearranged BCL6 alleles and their corresponding RNA and protein species in two DLCL biopsies and one tumor cell line which carried the t(3;14)(q27;q32) translocation involving the BCL6 and immunoglobulin heavy-chain (IgH) loci. In all three cases, the breakpoints were mapped within the IgH switch region and the BCL6 first intron, leading to the juxtaposition of part of the IgH locus upstream and in the same transcriptional orientation to the BCL6 coding exons. An analysis of cDNA clones showed that these recombinations generate chimeric IgH-BCL6 transcripts which initiated from IgH germline transcript promoters (I mu or I gamma 3), but retain a normal BCL6 coding domain. In the tumor cell line, the chimeric I gamma 3-BCL6 allele, but not the germline BCL6 gene, was transcriptionally active and produced a normal BCL6 protein. These findings indicate that t(3;14) translocations alter BCL6 expression by promoter substitution and imply that the consequence of these alterations is the deregulated expression of a normal BCL6 protein.

Isolation of motile and non-motile insertional mutants of Campylobacter jejuni: the role of motility in adherence and invasion of eukaryotic cells

A method of insertional mutagenesis for naturally transformable organisms has been adapted from Haemophilus influenzae and applied to the study of the pathogenesis of Campylobacter jejuni. A series of kanamycin-resistant insertional mutants of C. jejuni 81-176 has been generated and screened for loss of ability to invade INT407 cells. Eight noninvasive mutants were identified which showed 18-200-fold reductions in the level of invasion compared with the parent. Three of these eight show defects in motility, and five are fully motile. The three mutants with motility defects were further characterized to evaluate the method. One mutant, K2-32, which is non-adherent and non-invasive, has an insertion of the kanamycin-resistance cassette into the flaA flagellin gene and has greatly reduced motility and a truncated flagellar filament typical of flaA mutants. The adherent non-invasive mutants K2-37 and K2-55 are phenotypically paralysed, i.e. they have a full-length flagellar filament but are non-motile. All three mutants show an aberration in flagellar structure at the point at which the filament attaches to the cell. Mutants K2-37 and K2-55 represent overlapping deletions affecting the same gene, termed pflA (paralysed flagella). This gene encodes a predicted protein of 788 amino acid residues and a molecular weight of 90,977 with no significant homology to known proteins. Site-specific insertional mutants into this open reading frame result in the same paralysed flagellar phenotype and the same invasion defects as the original mutants. The differences in adherence between the two classes of flagellar mutant suggest that flagellin can serve as a secondary adhesion, although other adhesins mediate a motility-dependent internalization process. Characterization of the mutants at the molecular level and in animal models should further contribute to our understanding of the pathogenicity of these organisms.

Bioinspired trimodal macro/micro/nano-porous scaffolds loading rhBMP-2 for complete regeneration of critical size bone defect

Critical size bone defects raise great demands for efficient bone substitutes. Mimicking the hierarchical porous architecture and specific biological cues of natural bone has been considered as an effective strategy to facilitate bone regeneration. Herein, a trimodal macro/micro/nano-porous scaffold loaded with recombinant human bone morphogenetic protein-2 (rhBMP-2) was developed. With mesoporous bioactive glass (MBG) as matrix, a trimodal MBG scaffold (TMS) with enhanced compressive strength (4.28 MPa, porosity of 80%) was prepared by a "viscosity controlling" and "homogeneous particle reinforcing" multi-template process. A 7.5 nm, 3D cubic (Im3m) mesoporous structure was tailored for a "size-matched entrapment" of rhBMP-2 to achieve sustained release and preserved bioactivity. RhBMP-2-loaded TMS (TMS/rhBMP-2) induced excellent cell attachment, ingrowth and osteogenesis in vitro. Further in vivo ectopic bone formation and orthotopic rabbit radius critical size defect results indicated that compared to the rhBMP-2-loaded bimodal macro/micro- and macro/nano-porous scaffolds, TMS/rhBMP-2 exhibited appealing bone regeneration capacity. Particularly, in critical size defect, complete bone reconstruction with rapid medullary cavity reunion and sclerotin maturity was observed on TMS/rhBMP-2. On the basis of these results, TMS/rhBMP-2 developed here represents a promising bone substitute for clinical application and the concepts proposed in this study might provide new thoughts on development of future orthopedic biomaterials.

STATEMENT OF SIGNIFICANCE

Limited self-regenerating capacity of human body makes the reconstruction of critical size bone defect a significant challenge. Current bone substitutes often exhibit undesirable therapeutic efficacy due to poor osteoconductivity or low osteoinductivity. Herein, TMS/rhBMP-2, an advanced mesoporous bioactive glass (MBG) scaffold with osteoconductive trimodal macro/micro/nano-porosity and osteoinductive rhBMP-2 delivery was developed. The preparative and mechanical problems of hierarchical MBG scaffold were solved without affecting its excellent biocompatibilities, and rhBMP-2 immobilization in sizematched mesopores was first explored. Combining structural and biological cues, TMS/rhBMP-2 achieved a complete regeneration with rapid medullary cavity reunion and sclerotin maturity in rabbit radius critical size defects. The design conceptions proposed in this study might provide new thoughts on development of future orthopedic biomaterials.

Bioinspired, Injectable, Quaternized Hydroxyethyl Cellulose Composite Hydrogel Coordinated by Mesocellular Silica Foam for Rapid, Noncompressible Hemostasis and Wound Healing

Massive bleeding control and anti-infection are the major challenges for urgent trauma with deep and noncompressible hemorrhage in both clinic and battlefield. Inspired by the coordinated primarily blood clot formation and secondly coagulation cascade activation in natural hemostasis process, an injectable, quaternized hydroxyethyl cellulose/mesocellular silica foam (MCF) hydrogel sponge (QHM) for both hemorrhage control and antibacterial activities were prepared via one-pot radical graft copolymerization. The as-prepared QHMs exhibited instant water-triggered expansion and superabsorbent capacity and thereby effectively facilitated blood components concentration. Moreover, the QHM1 with appropriate amount of MCF (9.82 w/w %) could further activate the coagulation factors. Synergistically, the QHM1 could reduce the plasma clotting time to 59 ± 4% in vitro and showed less blood loss than commercially available hemostatics in vivo noncompressible hemorrhage models of lethal rabbit-liver defect. Furthermore, the QHM with a quaternary ammonium groups density of 2.732 mmol/g exhibited remarkable antibacterial activities and excellent cytocompatibility. With the efficient hemostasis efficacy and excellent antibacterial behavior, QHM dramatically facilitated the wound healing in a full-thickness skin defect model in vivo. Thus, this QHM represents a promising hemostatic in more widespread clinical application.

Phosphorylation of the p34 subunit of human single-stranded-DNA-binding protein in cyclin A-activated G1 extracts is catalyzed by cdk-cyclin A complex and DNA-dependent protein kinase

The human single-stranded-DNA-binding protein (HSSB, also called RP-A) is a trimeric complex (p70, p34, and p14) required for multiple functions in DNA transactions. We report here that the p34 subunit of HSSB was hyperphosphorylated by kinase activities present in G1 extract (obtained from HeLa cells in G1 phase) preincubated with human cyclin A. This hyperphosphorylated HSSB product included at least four species of p34 that migrated more slowly through denaturing polyacrylamide gels than the hypophosphorylated form. Fractionation of cyclin A-activated G1 extract identified two kinases involved in the hyperphosphorylation of HSSB p34: cdk-cyclin A complex and DNA-dependent p350 protein kinase (DNA-PK). Kinetic analysis revealed that in cyclin A-activated G1 extract, p34 was first phosphorylated by cdk-cyclin A prior to the action of DNA-PK. Addition of p21cip1, a specific inhibitor of cdk-cyclin A but not DNA-PK, nearly abolished the hyperphosphorylation of HSSB p34 in G1 extract preincubated with cyclin A. This suggests a requirement of the cdk-cyclin A activity for the phosphorylation of p34 by DNA-PK in G1 extract.

Synergy among thymol, eugenol, berberine, cinnamaldehyde and streptomycin against planktonic and biofilm-associated food-borne pathogens

Essential oils have been found to exert antibacterial, antifungal, spasmolytic, and antiplasmodial activity and therapeutic effect in cancer treatment. In this study, the antibacterial activities of four main essential oils' components (thymol (Thy), eugenol (Eug), berberine (Ber), and cinnamaldehyde (Cin)) were evaluated against two food-borne pathogens, Listeria monocytogenes and Salmonella Typhimurium, either alone or in combination with streptomycin. Checkerboard assay demonstrated that Thy and Cin elicited a synergistic effect with streptomycin against L. monocytogenes, while a synergy existed between Cin or Eug and streptomycin against Salm. Typhimurium. Further experiments showed that this synergy was sufficient to eradicate biofilms formed by these two bacteria. Thus, our data highlighted that the combinations of specific components from essential oils and streptomycin were useful for the treatment of food-borne pathogens, which might help prevent the spread of antibiotic resistance through improving antibiotic effectiveness.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study has shown the synergistic effect of four components of essential oil (thymol, eugenol, berberine and cinnamaldehyde) combined with streptomycin on planktonic and biofilm-associated food-borne pathogens Listeria monocytogenes and Salmonella Typhimurium. These findings indicate that combination of specific components of essential oils with streptomycin may provide alternative methods to overcome the problem of food-borne bacteria both in suspension and in biofilm.

Tannic acid-loaded mesoporous silica for rapid hemostasis and antibacterial activity

The as-prepared tannic acid (TA)-load mesoporous silica via electrostatic adsorption (TMS) exhibited excellent hemorrhage control by both TA-induced faster blood contact and plasma protein crosslinking, and MS-initiated water absorption, blood components concentration and coagulation factors activation, and good antibacterial properties.

Mapping of amino acid residues in the p34 subunit of human single-stranded DNA-binding protein phosphorylated by DNA-dependent protein kinase and Cdc2 kinase in vitro

Human single-stranded DNA-binding protein (HSSB, also called RPA), is a heterotrimeric complex that consists of three subunits, p70, p34, and p11. HSSB is essential for the in vitro replication of SV40 DNA and nucleotide excision repair. It also has important functions in other DNA transactions, including DNA recombination, transcription, and double-stranded DNA break repair. The p34 subunit of HSSB is phosphorylated in a cell cycle-dependent manner. Both Cdc2 kinase and the DNA-dependent protein kinase (DNA-PK) phosphorylate HSSB-p34 in vitro. In this study, we show that efficient phosphorylation of HSSB-p34 by DNA-PK requires Ku as well as DNA. The DNA-PK phosphorylation sites in HSSB-p34 have been mapped at Thr-21 and Ser-33. Kinetic studies demonstrated that a phosphate residue is first incorporated at Thr-21 followed by the incorporation of a second phosphate residue at Ser-33. We also identified Ser-29 as the major Cdc2 kinase phosphorylation site in the p34 subunit.

Fractional optical vortex beam induced rotation of particles

We experimentally demonstrate optical rotation and manipulation of microscopic particles by use of optical vortex beams with fractional topological charges, namely fractional optical vortex beams, which are coupled in an optical tweezers system. Like the vortex beams with integer topological charges, the fractional optical vortex beams are also capable of rotating particles induced by the transfer of orbital angular momentum. However, the unique radial opening (low-intensity gap) in the intensity ring encompassing the dark core, due to the fractional nature of the beam, hinders the rotation significantly. The fractional vortex beam's orbital angular momentum and radial opening are exploited to guide and transport microscopic particles.

Polyester microfiber and natural organic matter impact microbial communities, carbon-degraded enzymes, and carbon accumulation in a clayey soil

Microplastics can alter microbial communities and enzymatic activities in soils. However, the influences of microplastics on soil carbon cycling which driven by microbial communities remain largely unknown. In this study, we investigated the effects of polyester microfiber (PMF) and natural organic matter（OM）on soil microbial communities, carbon-degraded enzymes, and carbon accumulation through an incubation experiment. Our results showed that the addition of PMF increased the activities of soil cellulase and laccase but did not impact soil bacterial and fungal communities too much. However, the addition of OM largely altered soil microbial communities and the activities of carbon-degraded enzymes, then mitigated the PMF effects on the activities of soil cellulase and laccase. On the other hand, greater alpha diversity of bacterial community attached on PMF was observed than those in the surrounding soils. The interaction of PMF and OM increased the richness of bacterial community in soils and on PMF. More importantly, we observed that the accumulation of natural organic carbon in soils reduced with increasing PMF. Thus, our results provide valuable insights into the effects of microplastics on soil organic carbon dynamics and microbial communities, and further work is required to clarify the biochemical processes at the surface of microplastics.

PEGylated poly(glycerol sebacate)-modified calcium phosphate scaffolds with desirable mechanical behavior and enhanced osteogenic capacity

Calcium phosphate (CaP) scaffolds have been widely used as bone graft substitutes, but undesirable mechanical robustness and bioactivity greatly hamper its availability in clinic application. To address these issues, PEGylated poly (glycerol sebacate) (PEGS), a hydrophilic elastomer, was used to modify a model calcium phosphate cement (CPC) scaffold for bone regeneration in this study. The PEGS pre-polymer with PEG content from 0% to 40% was synthesized and was subsequently coated onto the pre-fabricated CPC scaffolds by facile infiltration and thermal-crosslink process. Compression strength and toughness of the CPC/PEGS composite scaffold (defined as CPX/Y, X referred to the PEG content in PEGS and Y referred to PEGS amount in final scaffold) were effectively tailored with increasing coating amount and PEG content, and CPX/Y exhibited an optimal compressive strength of 3.82MPa and elongation at break of 13.20%, around 5-fold and 3-fold enhancement compared to the CPC. In vitro cell experiment with BMSCs as model indicated that coating and PEG-modified synchronously facilitated cell attachment and proliferation in a dose-dependent manner. Particularly, osteogenic differentiation of BMSCs on PEGS/CPC scaffold was strongly enhanced, especially for CP20/18. Further in vivo experiments confirmed that PEGS/CPC induced promoted osteogenesis in striking contrast to CPC and PGS/CPC. Collectively, hybrids scaffolds (around 18% coating amount and PEG content from 20% to 40%) with the combination of enhanced mechanical behavior and up-regulated cellular response were optimized and PEGS/CaP scaffolds can be deemed as a desirable option for bone tissue engineering.

STATEMENT OF SIGNIFICANCE

Insufficient mechanical robustness and bioactivity still limit the availability of calcium phosphate (CaP) scaffolds in clinic application. Herein, calcium phosphate cement (CPC) scaffold, as a model CaP-matrix material, was modified with PEGylated PGS (PEGS) polymers by facile infiltration and thermal-crosslink process. Such biomimetic combination of PEGS and CaP-matrix porous scaffold was first explored, without affecting its porous structure. In this study, CPC scaffold was endowed with robust mechanical behavior and promoted bioactivity by simultaneously optimizing the amount of polymer-coating and the PEG content in PGS. In rat critical-sized calvarial defects repairing, osteogenic efficacy of PEGS/CPC further demonstrated the potential for application in bone tissue regeneration. The design concept proposed in this study might provide new insights into the development of future tissue engineering materials.

Inhibition of DNA2 nuclease as a therapeutic strategy targeting replication stress in cancer cells

Replication stress is a characteristic feature of cancer cells, which is resulted from sustained proliferative signaling induced by activation of oncogenes or loss of tumor suppressors. In cancer cells, oncogene-induced replication stress manifests as replication-associated lesions, predominantly double-strand DNA breaks (DSBs). An essential mechanism utilized by cells to repair replication-associated DSBs is homologous recombination (HR). In order to overcome replication stress and survive, cancer cells often require enhanced HR repair capacity. Therefore, the key link between HR repair and cellular tolerance to replication-associated DSBs provides us with a mechanistic rationale for exploiting synthetic lethality between HR repair inhibition and replication stress. DNA2 nuclease is an evolutionarily conserved essential enzyme in replication and HR repair. Here we demonstrate that DNA2 is overexpressed in pancreatic cancers, one of the deadliest and more aggressive forms of human cancers, where mutations in the KRAS are present in 90–95% of cases. In addition, depletion of DNA2 significantly reduces pancreatic cancer cell survival and xenograft tumor growth, suggesting the therapeutic potential of DNA2 inhibition. Finally, we develop a robust high-throughput biochemistry assay to screen for inhibitors of the DNA2 nuclease activity. The top inhibitors were shown to be efficacious against both yeast Dna2 and human DNA2. Treatment of cancer cells with DNA2 inhibitors recapitulates phenotypes observed upon DNA2 depletion, including decreased DNA double strand break end resection and attenuation of HR repair. Similar to genetic ablation of DNA2, chemical inhibition of DNA2 selectively attenuates the growth of various cancer cells with oncogene-induced replication stress. Taken together, our findings open a new avenue to develop a new class of anticancer drugs by targeting druggable nuclease DNA2. We propose DNA2 inhibition as new strategy in cancer therapy by targeting replication stress, a molecular property of cancer cells that is acquired as a result of oncogene activation instead of targeting currently undruggable oncoprotein itself such as KRAS.

Biophysical effects of adrenaline on the smooth muscle of the rabbit common carotid artery

Effects of adrenaline on the smooth muscle of the rabbit common carotid artery were studied by the partitional chamber method. The experiments on excitation-contraction coupling were carried out in isotonic Krebs solution; the other experiments were carried out in hypertonic Krebs solution. Adrenaline (10(-7) g/ml) caused rhythmical electrical and mechanical activity of arterial strips in isotonic Krebs solution. By addition of adrenaline (10(-5) g/ml), the membrane was depolarized by about 10 mv and the amplitude of the electrotonic potential was decreased by 40-50% of the control in hypertonic Krebs solution. Present experimental results suggest that the depolarization of the membrane and the decrease of the amplitude of the electrotonic potential in the artery are due to the increase of Na and Cl conductance. Contraction appeared in all preparations exposed to 10(-8) g/ml adrenaline; at that concentration membrane potential and membrane resistance showed little or no change.

Multicellularity-interweaved bone regeneration of BMP-2-loaded scaffold with orchestrated kinetics of resorption and osteogenesis

Synchronization of material resorption and new bone formation is vital to achieve harmonious bone regeneration in the treatment of large bone defects. To exposit the resorption/osteogenesis properties in the guided bone repairing, rhBMP-2-loaded trimodal macro/micro/nano-porous bioactive glass scaffolds (TMS-rhBMP-2) were set as substrate model. We penetratingly investigated the particular function of hierarchical structure and incorporated rhBMP-2 in the resorption/osteogenesis, and dissected the cellular interplay throughout the regenerative procedure. The results suggested that rhBMP-2 significantly facilitated osteoclastogenesis-mediated scaffold degradation and strikingly up-regulated mesenchymal stem cells (MSCs)-involved osteogenesis in vitro. Further gene microarray and related proteins expression indicated that in the presence of rhBMP-2, MSCs rather than differentiated MSCs could exert synergistic effects on osteoclastogenesis, osteoclasts maturation and resorptive function; meanwhile, rhBMP-2-induced MSCs osteogenesis was also strengthened by the osteoclasts. In vivo micro-CT, X-ray, kinetic and histological analyses qualitatively and quantitively demonstrated the optimized coupling of bioresorption/osteogenesis and the most rapid regeneration in TMS-rhBMP-2. Consequently, with rhBMP-2 acted as ignitor and MSCs/osteoclasts interaction as booster, a harmonious bone regeneration was obtained. Besides, long-term magnetic resonance imaging (MRI) in virtue of Gd³⁺ suggested that the degradation products mainly distributed in liver and spleen, verifying the accumulation/discharge profiles and safety application of TMS-rhBMP-2 system in vivo. This study will not merely provide guidance for the design of clinical bone repairing materials, but shed substantial light on the multicell-mediated tissue regeneration.

Antitumor activity of expanded human tumor-infiltrating gammadelta T lymphocytes

BACKGROUND

The objective of this study was to investigate the antitumor activity of selectively expanded gammadelta T cells in tumor-infiltrating lymphocytes (gammadeltaTILs) or tumor ascites lymphocytes (gammadeltaTALs) from patients with colorectal and ovarian epithelial carcinoma (OEC) in vitro and in vivo.

METHODS

gammadeltaTILs/TALs were expanded by the solid-phase antibody method; their cytolytic and proliferative activities in vitro were detected by the MTT method and 3H-TdR incorporation and their effect in vivo was evaluated by the nude mice model.

RESULTS

Expanded gammadeltaTILs from colorectal tumors demonstrated marked cytotoxicities to allogeneic human colon adenocarcinoma HR8348 and lymphoma Daudi cells, as well as xenogeneic murine thymoma EL-4 cell lines. Cytokines, including IL-2, IL-4, IL-12, IL-15, TNF-alpha and INF-gamma, could promote the cytotoxicities of gammadeltaTILs to tumor cells, whereas IL-10, GM-CSF and TFG-beta had no effect on such killing activities. Rested gammadeltaTILs could proliferate strongly in response to mitomycin C-treated Daudi and EL-4 tumor cells, but not to HR8348 tumor cells, suggesting that the latter might possess only cytotoxicity-related antigen recognized by gammadeltaTILs. Either alphabetaTILs or gammadeltaTILs from patients with OEC displayed cytotoxicities to allogeneic or autologous OEC cell lines at a similar strength in vitro. Transferring gammadeltaTILs into Daudi cell-bearing BALB/c nude mice with an injection of IL-2 was able to maintain a high survival rate of the mice for 30 days, when compared with mice treated with alphabetaTILs or without any treatment (p < 0.05). Without coinjection of IL-2, after 3 months of Daudi tumor inoculation, a high survival rate was observed in gammadeltaTIL-treated mice. Similarly, adoptive gammadeltaTALs from the ascites of patients with OEC transferred into nude mice displayed a stronger antitumor response to OEC SKOV3 cells than alphabetaTALs in vivo. Tumor volumes in gammadeltaTAL-treated mice were smaller than in alphabetaTAL-treated or non-TAL-treated mice within the period from day 23 to day 50 after tumor inoculation (p < 0.05). Fifty days after SKOV3 tumor inoculation, a decreasing trend of carcinogenic rate was observed in gammadeltaTAL-treated nude mice.

CONCLUSION

Taken together, our results suggest that gammadeltaT cells could be a new candidate for adoptive immunotherapy in the future treatment of patients with cancer.

Bio-inspired, bio-degradable adenosine 5′-diphosphate-modified hyaluronic acid coordinated hydrophobic undecanal-modified chitosan for hemostasis and wound healing

Uncontrolled hemorrhage and wound infection are crucial causes of trauma-associated death in both the military and the clinic. Therefore, developing an efficient and rapid hemostatic method with biocompatibility, easy degradation, and wound healing is of great importance and desirability. Inspired by spontaneous blood cell plug formation in the hemostasis process, an adenosine 5′-diphosphate modified pro-coagulation hyaluronic acid (HA-ADP) coordinated with enhanced antibacterial activity of undecanal-modified chitosan (UCS) was fabricated through physical electrostatic cross-linking and freeze-drying. The as-prepared hydrogel sponges showed a porous structure suitable for blood cell adhesion. In particular, the hydrogel exhibited excellent antibacterial ability and promoted the adhesion of platelets and red blood cells, thus inducing a prominent pro-coagulation ability via platelet activation, which exhibits a shorter hemostasis time (58.94% of control) in vitro. Compared with commercially available CELOX and gelatin sponge (GS), HA-ADP/UCS accelerates hemostasis and reduces blood loss in both rat tail amputation and rat artery injury models. Furthermore, all the samples exhibited superior cytocompatibility and biodegradability. Due to these performances, HA-ADP/UCS promoted full-thickness skin defect healing significantly in vivo. All the properties of HA-ADP/UCS suggest that it has great potential for translation as a clinical application material for hemostatic and wound healing.

•

Using adenosine 5'-diphosphate, a physiologically platelet agonist, to modify hyaluronic acids to promote hemostatic effect.

•

Using undecanal to modify Chitosan fabricated with HA-ADP via electrostatic interactions and noncovalent crosslinking method.

•

The hydrogel sponges have excellent antibacterial properties related to the bacterial disruption abilities of UCS.

•

HA-ADP/UCS posed a great hemostatic performance, promoting wound healing by regulating inflammatory response in early stage.

Expression of the autoimmune Fcgr2b NZW allele fails to be upregulated in germinal center B cells and is associated with increased IgG production

The inhibitory receptor FcgammaRIIb regulates B-cell functions. Genetic studies have associated Fcgr2b polymorphisms and lupus susceptibility in both humans and murine models, in which B cells express reduced FcgammaRIIb levels. Furthermore, FcgammaRIIb absence results in lupus on the appropriate genetic background, and lentiviral-mediated FcgammaRIIb overexpression prevents disease in the NZM2410 lupus mouse. The NZM2410/NZW allele Fcgr2b is, however, located in-between Sle1a and Sle1b, two potent susceptibility loci, making it difficult to evaluate Fcr2b(NZW) independent contribution. By using two congenic strains that each carries only Sle1a (B6.Sle1a(15-353)), or Fcr2b(NZW) in the absence of Sle1a or Sle1b (B6.Sle1(111-148)), we show that the Fcr2b(NZW) allele does not upregulate its expression on germinal center B cells and plasma cells, as does the C57BL/6 allele on B6.Sle1a(15-353) B cells. Furthermore, in the absence of the flanking Sle1a and Sle1b, Fcr2b(NZW) does not produce an autoimmune phenotype, but is associated with an increased number of class-switched plasma cells. These results show that while a lower level of FcgammaRIIb does not by itself induce the development of autoreactive B cells, it has the potential to amplify the contribution of autoreactive B cells induced by other lupus-susceptibility loci by enhancing the production of class-switched plasma cells.

Dexamethasone regulates basic fibroblast growth factor, nerve growth factor and S100beta expression in cultured hippocampal astrocytes

Glucocorticoids regulate hippocampal neuron survival during fetal development, in the adult, and during aging; however, the mechanisms underlying the effects are unclear. Since astrocytes contain adrenocortical receptors and synthesize and release a wide variety of growth factors, we hypothesized that glucocorticoids may alter neuron-astrocyte interactions by regulating the expression of growth factors in hippocampal astrocytes. In this study, three growth factors, which are important for hippocampal neuron development and survival, were investigated: basic fibroblast growth factor (bFGF), nerve growth factor (NGF), and S100beta. Enriched type I astrocyte cultures were treated with 1 microM dexamethasone (DEX), a synthetic glucocorticoid, for up to 120 h. Cells and culture medium were collected and total RNA and protein were measured at 6, 12, 24, 48, 72, 96 and 120 h after the initiation of hormone treatment. Growth factor mRNA levels were measured and quantified using solution hybridization-RNase protection assays and protein levels were quantified using ELISA methods. We report that DEX stimulates the bFGF mRNA levels over the 120-h treatment. In contrast, DEX suppresses NGF mRNA continuously over the same period of treatment. DEX induces a biphasic response in S100beta mRNA levels. In addition, some of the changes in gene expression are translated into parallel changes in protein levels of these growth factors. Our results demonstrate that dexamethasone can differentially regulate the expression of growth factors in hippocampal astrocytes in vitro. This suggests that one of the mechanisms through which glucocorticoids affect hippocampal functions may be by regulating the expression of astrocyte-derived growth factors.

Meta-analysis of prevalence of wheezing and recurrent wheezing in infants

BACKGROUND

Wheezing affects children's quality of life, and is related with asthma in childhood. Although prevalence of wheezing has been previously studied in several countries, there is no reference of worldwide prevalence in infants. The aim of this meta-analysis is to estimate the prevalence of wheezing and recurrent wheezing in infants aged up to two years, and compare the prevalence across world regions.

METHODS

Literature search was conducted in MEDLINE and SCOPUS databases, looking for observational studies published up to June 2016, including as keywords "prevalence" or "epidemiology" combined with "wheeze", "wheezing" or "asthma symptoms" and "infant" or "preschool". Fast*Pro software and random effects Bayesian model were used. Heterogeneity was estimated using I² statistic, and sensitivity analyses were performed.

RESULTS

We identified 109 studies after duplicates were removed. After exclusions, 14 studies were included in the meta-analysis. Prevalence of wheezing and recurrent wheezing were 36.06% (95% CI 35.17-36.96), and 17.41% (95% CI 16.74-18.09), respectively. In European countries, prevalence of wheezing was 30.68% (95% CI 28.97-32.45), and 12.35% (95% CI 11.27-13.47) for recurrent wheezing. Prevalence of wheezing and recurrent wheezing in Latin America were higher, 40.55% (95% CI 39.40-41.71), and 19.27% (95% CI 18.44-20.11), respectively. In Africa, prevalence of wheezing was 15.97% (95% CI 14.05-18.00). Low or no heterogeneity was found in all cases.

CONCLUSIONS

More than one third of infants suffer from wheezing and almost one fifth from recurrent wheezing, being these illnesses especially prevalent in Latin American countries, pointing out an important public health problem.