A smart core-sheath nanofiber that captures and releases red blood cells from the blood

A smart core-sheath nanofiber for non-adherent cell capture and release is demonstrated. The nanofibers are fabricated by single-spinneret electrospinning of poly(N-isopropylacrylamide) (PNIPAAm), polycaprolactone (PCL) and nattokinase (NK) solution blends. The self-assembly of PNIPAAm and PCL blends during the electrospinning generates the core-sheath PCL/PNIPAAm nanofibers with PNIPAAm as the sheath. The PNIPAAm-based core-sheath nanofibers are switchable between hydrophobicity and hydrophilicity with temperature change and enhance stability in the blood. When the nanofibers come in contact with blood, the NK is released from the nanofibers to resist platelet adhesion on the nanofiber surface, facilitating the direct capture and isolation of red blood cells (RBCs) from the blood above phase-transition temperature of PNIPAAm. Meanwhile, the captured RBCs are readily released from the nanofibers with temperature stimuli in an undamaged manner. The release efficiency of up to 100% is obtained while maintaining cellular integrity and function. This work presents promising nanofibers to effectively capture non-adherent cells and release for subsequent molecular analysis and diagnosis of single cells.

J/psi production versus centrality, transverse momentum, and rapidity in Au+Au collisions at square root sNN=200 GeV

The PHENIX experiment at the BNL Relativistic Heavy Ion Collider (RHIC) has measured J/psi production for rapidities -2.2<y<2.2 in Au+Au collisions at square root sNN=200 GeV. The J/psi invariant yield and nuclear modification factor RAA as a function of centrality, transverse momentum, and rapidity are reported. A suppression of J/psi relative to binary collision scaling of proton-proton reaction yields is observed. Models which describe the lower energy J/psi data at the CERN Super Proton Synchrotron invoking only J/psi destruction based on the local medium density predict a significantly larger suppression at RHIC and more suppression at midrapidity than at forward rapidity. Both trends are contradicted by our data.

Development of Diagnostic Biomarkers for Detecting Diabetic Retinopathy at Early Stages Using Quantitative Proteomics

Diabetic retinopathy (DR) is a common microvascular complication caused by diabetes mellitus (DM) and is a leading cause of vision impairment and loss among adults. Here, we performed a comprehensive proteomic analysis to discover biomarkers for DR. First, to identify biomarker candidates that are specifically expressed in human vitreous, we performed data-mining on both previously published DR-related studies and our experimental data; 96 proteins were then selected. To confirm and validate the selected biomarker candidates, candidates were selected, confirmed, and validated using plasma from diabetic patients without DR (No DR) and diabetics with mild or moderate nonproliferative diabetic retinopathy (Mi or Mo NPDR) using semiquantitative multiple reaction monitoring (SQ-MRM) and stable-isotope dilution multiple reaction monitoring (SID-MRM). Additionally, we performed a multiplex assay using 15 biomarker candidates identified in the SID-MRM analysis, which resulted in merged AUC values of 0.99 (No DR versus Mo NPDR) and 0.93 (No DR versus Mi and Mo NPDR). Although further validation with a larger sample size is needed, the 4-protein marker panel (APO4, C7, CLU, and ITIH2) could represent a useful multibiomarker model for detecting the early stages of DR.

A novel thin-layer amperometric detector based on chemically modified ring-disc electrode and its application for simultaneous measurements of nitric oxide and nitrite in rat brain combined with in vivo microdialysis

A novel thin-layer amperometric detector (TLAD) based on chemically modified ring-disc electrode and its application for simultaneous measurements of nitric oxide (NO) and nitrite (NO(2)(-)) in rat brain were demonstrated in this work. The ring-disc electrode was simultaneously sensitive to nitric oxide (NO) and nitrite (NO(2)(-)) by modifying its inner disc with electropolymerized film of cobalt(II) tetraaminophthalocyanine (polyCoTAPc)/Nafion and its outer ring with poly(vinylpyridine) (PVP), respectively. The ring-disc electrode was used to constitute a novel TLAD in radial flow cell for simultaneous measurements of NO and NO(2)(-) in rat brain combined with techniques of high performance liquid chromatography (HPLC) and in vivo microdialysis. It was found that the basal concentration of NO in the caudate nucleus of rat brain is lower than 1.0x10(-7) mol l(-1), NO(2)(-) concentration is 5.0x10(-7) mol l(-1) and NO exists in brain maybe mainly in the form of its decomposed product.

Transfection of Smac sensitizes tumor cells to etoposide-induced apoptosis and eradicates established human hepatoma in vivo

A major concern in clinical treatment of cancers is resistance of tumors such as hepatocellular carcinoma (HCC) and osteosarcoma to current chemotherapy protocols. Here, we reported that overexpression of second mitochondria-derived activator of caspase (Smac) sensitized osteosarcoma cells and HCC cells in vitro to chemotherapeutic drugs-induced apoptosis. Constitutive expression of Smac resulted in enhanced Bax accumulation on mitochondria upon etoposide stimulation and inhibited Bcl-2-induced antiapoptosis activity. Thus, Smac would sensitize tumor cells to chemotherapeutic drugs in part through promoting Bax translocation to mitochondria and bypassing Bcl-2 block. Moreover, we demonstrated that blockade of Smac expression by antisense smac did not impair etoposide-induced apoptosis; however, p53-induced apoptosis was impaired in smac deficient Saos-2 cell. This suggested Smac might be required in p53-induced apoptosis. Most importantly, complete eradication of HepG2 xenografts in vivo was achieved upon combined therapy with Ad-Smac and 5-Fu. Thus, overexpression of Smac in tumor cells might be a potent strategy for cancer treatment by sensitization of tumor cells to chemotherapeutic drugs.

Pets keeping in home, parental atopy, asthma, and asthma-related symptoms in 12,910 elementary school children from northeast China

The effects of pet exposure and parental atopy on respiratory symptoms were investigated in 12,910 children residing in twelve districts of northeast China. Responses to a self-administered questionnaire completed by parents of children were used to ascertain children with persistent cough, persistent phlegm, doctor-diagnosed asthma, current asthma and current wheeze. Exposure to animals during pregnancy was positively associated with doctor-diagnosed asthma [adjusted odds ratio (ORs), 1.86; 95% confidence interval (CI) 1.35-2.57], current asthma (adjusted OR, 3.06; 95% CI, 1.95-4.81) and asthma-related symptoms. Pet exposure in the first year of life and currently having animals in household were also related to a significantly higher prevalence of doctor-diagnosed asthma and asthma-related symptoms in these children. Associations with respiratory symptoms strengthened with higher levels of animal exposure. Parental atopy increased the risk of asthma diagnosis (OR, 3.49; 95%CI, 2.84-4.30), current asthma (OR, 3.94; 95%CI, 2.81-5.54) and asthma-related symptoms. There was an interaction between parental atopy and pet exposure in persistent phlegm, but not in doctor-diagnosed asthma. We conclude that pet keeping and parental atopy increased the risk of respiratory symptoms in children. Parental atopy did modify the effect of pet exposure on persistent phlegm but not on doctor-diagnosed asthma.

PRACTICAL IMPLICATIONS

The relationship between exposure to animals and allergic respiratory diseases in childhood is controversial. Inconsistent with other cross-sectional studies mostly conducted in industrialized countries, our study indicates that exposure to animals may increase the occurrence of respiratory symptoms and diseases in children, and the associations with respiratory symptoms strengthened with higher levels of animal exposure parental atopy did modify the effect of pet exposure on persistent phlegm but not on doctor-diagnosed asthma. These findings support the view that measures should be taken to reduce animal exposure for children in China.

Observation of direct-photon collective flow in Au + Au collisions at √s(NN)] = 200 GeV

The second Fourier component v(2) of the azimuthal anisotropy with respect to the reaction plane is measured for direct photons at midrapidity and transverse momentum (p(T)) of 1-12 GeV/c in Au + Au collisions at √s(NN)] = 200 GeV. Previous measurements of this quantity for hadrons with p(T) < 6 GeV/c indicate that the medium behaves like a nearly perfect fluid, while for p(T) > 6 GeV/c a reduced anisotropy is interpreted in terms of a path-length dependence for parton energy loss. In this measurement with the PHENIX detector at the Relativistic Heavy Ion Collider we find that for p(T) > 4 GeV/c the anisotropy for direct photons is consistent with zero, which is as expected if the dominant source of direct photons is initial hard scattering. However, in the p(T) < 4 GeV/c region dominated by thermal photons, we find a substantial direct-photon v(2) comparable to that of hadrons, whereas model calculations for thermal photons in this kinematic region underpredict the observed v(2).

Retinal proteome analysis in a mouse model of oxygen-induced retinopathy

To identify proteins that are involved in the molecular mechanisms of oxygen-induced retinopathy (OIR), a well-established model of blinding ischemic retinopathy, we quantitatively analyzed the retinal proteome in a mouse model of OIR. OIR was induced by exposing C57BL/6 mice on postnatal day 7 (P7) to 75% hyperoxia for 5 days, followed by 5 days in room air. Retinas from mice on P12 and P17, the hyperoxic and hypoxic phases, respectively, and control groups were examined using isobaric tags for relative and absolute quantitation (iTRAQ) and nano-LC-ESI-MS/MS. In total, 1422 retinal proteins were identified: 699 from the iTRAQ experiment and 1074 by nano-LC-ESI-MS/MS. Compared with control retinas in the iTRAQ study, OIR retinas upregulated and downregulated 21 and 17 proteins, respectively, in P17 retinas and 25 and 14 proteins, respectively, in P12 retinas. Of the differentially expressed proteins, the retinal expression of crystallin proteins, Müller cell-associated proteins, neurodegeneration-associated proteins, and angiogenesis-associated proteins, such as 150-kDa oxygen-regulated protein (ORP150), were analyzed. ORP150 colocalized to the neovascular tufts, and knockdown of ORP150 by siRNA decreased the levels of secreted VEGF in cultured retinal pigment epithelial cells. Moreover, intravitreal administration of siRNA targeting ORP150 significantly reduced the retinal neovascularization in OIR. In conclusion, our proteomic discovery method, coupled with targeted approaches, revealed many proteins that were differentially regulated in the mouse model of OIR. These proteins, including ORP150, are potential novel therapeutic targets for the treatment of proliferative ischemic retinopathy.

L-carnitine protects against cyclosporine-induced pancreatic and renal injury in rats

BACKGROUND

L-carnitine has protective effects against various types of injury. This study was designed to evaluate the beneficial effects of L-carnitine on pancreatic and renal injuries caused by cyclosporine (CsA).

METHODS

Rats maintained on a low sodium diet were given vehicle (olive oil, 1 mL/kg/d), CsA (15 mg/kg/d), L-carnitine (50 or 200 mg/kg/d), or a combination of CsA and L-carnitine for 4 weeks. The impact of L-carnitine on pancreatic injury was assessed by blood glucose levels, plasma insulin concentrations, and hemoglobulin A1c (HbA1c). In addition, the protective effects of L-carnitine against CsA-induced kidney injury were evaluated in terms of renal function, histopathology (inflammatory cell influx and tubulointerstitial fibrosis), oxidative stress (8-hydroxy 2'-deoxyguanosine, 8-OHdG), transforming growth factor-betal (TGF-β1), apoptosis (caspase-3), and autophagy (LC3-II).

RESULTS

CsA treatment caused diabetes, renal dysfunction, tubulointerstitial inflammation (ED-1-positive cells), and fibrosis, which were accompanied by an increase in 8-OHdG production and upregulation of TGF-β1, caspase-3, and LC3-II. Concomitant administration of L-carnitine increased plasma insulin concentrations, decreasing plasma glucose and HbA1c levels. In the kidney, L-carnitine induced dose-dependent improvement of renal function, inflammation, and fibrosis in parallel with suppression of the expression of TGF-β1 and 8-OHdG. Furthermore, the administration of L-carnitine at a high dose inhibited the expression of caspase-3 and LC3-II.

CONCLUSION

These findings suggest that L-carnitine has a protective effect against CsA-induced pancreatic and renal injuries.

Circulating microRNAs as potential non-invasive biomarkers for the early detection of hypertension-related stroke

Hypertension is one of the most important risk and modifiable factors for stroke. Crucial in managing the cerebrovascular damage caused by long-lasting and inadequately treated hypertension is not only lowering arterial blood pressure but also early predicting subtypes of hypertension-related stroke and applying more effective interventions. Accumulating evidence suggested that circulating microRNAs (miRNAs) could be developed as biomarkers for early recognition of the onset of a variety of diseases. The role of miRNAs has been extensively reviewed, involving cardiac hypertrophy, hypertensive heart failure, kidney failure and renal fibrosis. miRNA research in stroke is still in its infancy, although there are few literatures reviewing the role of miRNAs in the processes of hypertension-related stroke. This review summarizes current advances in miRNAs regulation of critical pathogenic process underlying hypertension, ischemic stroke and hemorrhagic stroke, and highlights the potential of using circulating miRNAs as noninvasive biomarkers for the early detection of hypertension-related stroke.

Mechanism of Platelet Activation and Hypercoagulability by Antithymocyte Globulins (ATG)

T cell depletion with antithymocyte globulins (ATG) can be complicated by thrombopenia and hypercoagulability. The underlying mechanism is still unclear. We found that binding of ATG to platelets caused platelet aggregation, α-granule release, membrane phosphatidylserine exposure and the rapid release of procoagulant platelet microvesicles (MV). Platelet activation and MV release were complement-dependent and required membrane insertion of C5b-8 but not stable lytic pore formation by C5b-9. ATG also activated platelets via binding to the low-affinity Fc gamma receptor FcγRII. However, only complement inhibition but not blockade of FcγRII prevented MV release and subsequent thrombin activation in plasma. In 19 hematopoietic stem cell and kidney transplant patients, ATG treatment resulted in thrombopenia and increased plasma levels of d-dimer and thrombin-antithrombin complexes. Flow cytometric analysis of complement fragments on platelet MV in patient plasma confirmed dose-dependent complement activation by ATG. However, the rapid rise in MV numbers observed in vitro was not seen during ATG treatment. In vitro experiments suggested that this was due to adherence of C3b-tagged MV to red blood cells via complement receptor CR1. These data suggest a clinically relevant link between complement activation and thrombin generation and offer a potential mechanism underlying ATG-induced hypercoagulability.

Recognition of diverse sequences by class I zinc fingers: asymmetries and indirect effects on specificity in the interaction between CF2II and A+T-rich elements

The Drosophila CF2II protein, which contains zinc fingers of the Cys2His2 type and recognizes an A+T-rich sequence, behaves in cell culture as an activator of a reporter chloramphenicol acetyltransferase gene. This activity depends on C-terminal but not N-terminal zinc fingers, as does in vitro DNA binding. By site-specific mutagenesis and binding site selection, we define the critical amino acid-base interactions. Mutations of single amino acid residues at the leading edge of the recognition helix are rarely neutral: many result in a slight change in affinity for the ideal DNA target site; some cause major loss of affinity; and others change specificity for as many as two bases in the target site. Compared to zinc fingers that recognize G+C-rich DNA, CF2II fingers appear to bind to A+T-rich DNA in a generally similar manner, but with additional flexibility and amino acid-base interactions. The results illustrate how zinc fingers may be evolving to recognize an unusually diverse set of DNA sequences.

Measurement of nitric oxide released in the rat heart with an amperometric microsensor

Nitric oxide (NO) plays an important role in various physiological processes, acting either as an intra- and intercellular messenger or as a toxic agent. The detection and quantification of NO have been accomplished by a variety of methodologies. In the present study, real-time production of NO in the rat heart was continuously measured by using a novel copper-platinum microparticle-modified NO electrochemical microsensor. The linearity range of the microsensor is between 8.0 x 10(-8) and 4.8 x 10(-6) mol L-1 and the detection limit is 3.0 x 10(-8) mol L-1. NO release from the rat heart stimulated by the agonists L-arginine and acetylcholine was observed, and the responses were decreased by the NO synthase inhibitor L-N omega-nitroarginine. In addition, the effect of sodium nitroprusside (SNP), a NO donor, was also studied. SNP increases the concentration of NO in the rat heart. The experiments showed that electrochemical detection is suitable for detecting and quantifying NO in biological systems.

In-depth proteomic analysis of mouse microglia using a combination of FASP and StageTip-based, high pH, reversed-phase fractionation

Microglia are major immune cells in the central nervous system. A characterization of microglia proteome would facilitate on the study of microglial functions in association with various neurodegenerative diseases. To build a reference proteome, we established a BV-2 microglial proteome to a depth of 5494 unique protein groups using a novel strategy that combined FASP, StageTip-based high pH fractionation, and high-resolution MS quickly and cost efficiently. By bioinformatics analysis, the BV-2 proteome is a valuable resource for studies of microglial function, such as in the immune response, inflammatory response, and phagocytosis. All MS data have been deposited in the ProteomeXchange with identifier PXD000168.

Comprehensive Study of Bioanalytical Platforms: Xanthine Oxidase

A comprehensive study of a general bioanalytical platform for biosensor applications is presented using xanthine oxidase (XnOx) as a case study within the framework of developing approaches of broad applicability. In this context, emphasis is placed on amperometric biosensors based on XnOx, which has been immobilized by covalent binding to gold electrodes modified with dithiobis-N-succinimidyl propionate. The immobilized XnOx layers have been characterized using atomic force microscopy under liquid conditions and quartz crystal microbalance techniques. In addition, spatially resolved mapping of enzymatic activity has been carried out using scanning electrochemical microscopy. Redox dyes of phenothiazine derivatives, specifically, thionine and methylene blue, have been found to work well as electron acceptors for reduced XnOx. The kinetic parameters and equilibrium constants of the mediated enzymatic oxidation of xanthine in the presence of the above-mentioned redox dyes have been calculated. The response of the enzymatic electrode to varying xanthine concentrations has been obtained in the presence of thionine or methylene blue as redox mediator in solution. Under these conditions, xanthine could be determined amperometrically at +0.2 V versus SSCE.

Prokaryotic Soluble Overexpression and Purification of Human VEGF165 by Fusion to a Maltose Binding Protein Tag

Human vascular endothelial growth factor (VEGF) is a key regulator of angiogenesis and plays a central role in the process of tumor growth and metastatic dissemination. Escherichia coli is one of the most common expression systems used for the production of recombinant proteins; however, expression of human VEGF in E. coli has proven difficult because the E. coli-expressed VEGF tends to be misfolded and forms inclusion bodies, resulting in poor solubility. In this study, we successfully produced semi-preparative amounts of soluble bioactive human VEGF165 (hVEGF). We created seven N-terminal fusion tag constructs with hexahistidine (His6), thioredoxin (Trx), glutathione S-transferase (GST), maltose-binding protein (MBP), N-utilization substance protein A (NusA), human protein disulfide isomerase (PDI), and the b'a' domain of PDI (PDIb'a'), and tested each construct for soluble overexpression in E. coli. We found that at 18°C, 92.8% of the MBP-tagged hVEGF to be soluble and that this tag significantly increased the protein's solubility. We successfully purified 0.8 mg of pure hVEGF per 500 mL cell culture. The purified hVEGF is stable after tag cleavage, contains very low levels of endotoxin, and is 97.6% pure. Using an Flk1⁺ mesodermal precursor cell (MPC) differentiation assay, we show that the purified hVEGF is not only bioactive but has similar bioactivity to hVEGF produced in mammalian cells. Previous reports on producing hVEGF in E. coli have all been based on refolding of the protein from inclusion bodies. To our knowledge, this is the first report on successfully expressing and purifying soluble hVEGF in E. coli.

The involvement of sigma receptors in the choice reaction performance deficits induced by phencyclidine

The present study investigated the effects of phencyclidine (PCP) on choice reaction in a 3-choice serial reaction time task for studying attentional function. PCP (3.2 mg/kg) significantly delayed choice reaction time and reduced choice accuracy. A novel sigma receptor antagonist N,N-dipropyl-2-[4-methoxy-3-(2-phenylethoxy)phenyl]-ethylamine monohydrochloride (NE-100) at 3.2 mg/kg, and 1-(cyclopropylmethyl)-4-[2'-4"-fluorophenyl)-2'-oxoethyl]piperidin e HBr (DuP734) at 1.0-3.2 mg/kg, but not 4-[2'-(4"-cyanophenyl)-2'-oxoethyl]-1-(cyclopropylmethyl)pip eridine (XJ448), antagonized both the delayed choice reaction time and the decreased choice accuracy elicited by PCP administration. The antagonism induced by NE-100 was blocked by the sigma receptor agonist (+)-N-allylnormetazocine HCl [(+)-SKF10,047]. These findings indicated that PCP (3.2 mg/kg) significantly induced attention deficit in a 3-choice serial reaction time task, and that this process may be mediated by sigma receptors.

Unfavorable prognosis of elderly patients with early-stage extranodal nasal-type NK/T-cell lymphoma

BACKGROUND

Extranodal nasal-type NK (natural killer)/T-cell lymphoma in elderly patients is rare, and its prognosis is unclear. This study aims to investigate the clinical characteristics and prognosis of this lymphoma.

PATIENTS AND METHODS

We analyzed 24 patients (age, >60 years old) with early-stage extranodal nasal-type NK/T-cell lymphoma. Among these patients, 23 received radiotherapy alone (n = 15) or radiotherapy and chemotherapy (n = 8) and 1 received chemotherapy alone.

RESULTS

Elderly patients with early-stage extranodal nasal-type NK/T-cell lymphoma were characterized by male predominance, good performance, large proportion of localized disease, more comorbidities, low-risk international prognostic index, and unfavorable prognosis. The 5-year cancer-specific survival (CSS), overall survival (OS), and progression-free survival (PFS) rates for all patients were 54.3%, 42.0%, and 40.2%, respectively. The 5-year CSS, OS, and PFS rates were 43.5%, 36.6%, and 34.1% in patients who received radiotherapy alone, and 50%, 50%, and 50% in patients who received radiotherapy and chemotherapy, respectively (P = 0.852 for CSS, P = 0.801 for OS, and P = 0.694 for PFS). Four patients died of treatment-related mortality.

CONCLUSION

Elderly patients with early-stage extranodal nasal-type NK/T-cell lymphoma exhibit poor prognosis and need special attention because of high treatment-related mortality.

The Profile of Angiogenic Factors in Vitreous Humor of the Patients with Proliferative Diabetic Retinopathy

OBJECTIVE

To explore the expression profile of angiogenic factors associated with proliferative diabetic retinopathy (PDR).

METHODS

Undiluted vitreous humor samples were obtained from 10 diabetic patients with PDR (10 eyes) and 9 non-diabtic patients (9 eyes). The concentrations of 60 angiogenic factors in the vitreous humor samples were measured by RayBio Angiogenic Cytokine Antibody Array. Some differentially expressed factors were further confirmed in vitreous humor by enzyme-linked immunosorbent assay (ELISA).

RESULTS

Compared with the non-diabetic controls, 20 differentially expressed factors with more than 1.50 fold changes were detected in patients with PDR. The median concentration of vascular endothelial growth factor (VEGF), interleukin 6 (IL-6), angiopoietin (ANG)-1, ANG-2, urokinase-type plasminogen activator receptor (uPAR), Follistatin and matrix metalloproteinases 9 (MMP-9) was significantly increased in vitreous samples from PDR compared to controls (P < 0.05). However, (MCP)-1, Angiogenin and Leptin was significantly lower in PDR eyes compared to controls (P < 0.05). In the verification assay using ELISA, ANG-1, ANG-2, IL-6, VEGF, MMP-9, hepatocyte growth factor (HGF) and placenta growth factor (PIGF) concentration were increased in patients with PDR compared to controls (all P-values < 0.05).

CONCLUSION

This is the first report of a comprehensive multiplex analysis to identify angiogenic factors associated with PDR. These angiogenic factors may contribute to the pathogenesis of PDR and may be targets for therapeutic strategies of PDR.