Exosome Isolation and Detection: From Microfluidic Chips to Nanoplasmonic Biosensor.

Exosomes are becoming more widely acknowledged as significant circulating indicators for the prognosis and diagnosis of cancer. Circulating exosomes are essential to the development and spread of cancer, according to a growing body of research. Using existing technology, characterizing exosomes is quite difficult. Therefore, a direct, sensitive, and targeted approach to exosome detection will aid in illness diagnosis and prognosis. The review discusses the new strategies for exosome isolation and detection technologies from microfluidic chips to nanoplasmonic biosensors, analyzing the advantages and limitations of these new technologies. This review serves researchers to better understand exosome isolation and detection methods and to help develop better exosome isolating and detecting devices for clinical applications.

Neuroprotective effect of green tea extract (-)-epigallocatechin-3-gallate in a preformed fibril-induced mouse model of Parkinson's disease.

Parkinson's disease (PD) is the second most common neurodegenerative disease characterized by the progressive degeneration of dopaminergic neurons in the substantia nigra (SN). The main bioactive component of green tea polyphenols (-)-epigallocatechin-3-gallate (EGCG) exerts protective effects against diseases such as neurodegenerative diseases and cancer. Therefore, this study investigated the effect of EGCG on the amelioration of neural damage in a chronic PD mouse model induced by α-synuclein preformed fibrils (α-syn-PFFs). A total of 20 C57BL/6J female mice were randomly divided into 3 groups: control group (saline, n = 6), model group (PFFs, n = 7), and prevention group (EGCG+PFFs, n = 7). A chronic PD mouse model was obtained by the administration of α-syn-PFFs by stereotaxic localization in the striatum. Behavioral tests were performed to evaluate PD-related anxiety-like behavior and motor impairments in the long-term PD progression. Tyrosine hydroxylase (TH) immuno-positive neurons and Ser129-phosphorylated α-syn (p-α-syn) were identified by immunohistochemistry. Pro-inflammatory and anti-inflammatory cytokines were measured by real-time quantitative PCR. EGCG pretreatment reduced anxiety-like behavior and motor impairments as revealed by the long-term behavioral test (2 weeks, 1 month, 3 months, and 6 months) on PD mice. EGCG also ameliorated PFF-induced degeneration of TH immuno-positive neurons and accumulation of p-α-syn in the SN and striatum at 6 months. Additionally, EGCG reduced the expression of pro-inflammatory cytokines while promoting the release of anti-inflammatory cytokines. EGCG exerts a neuroprotective effect on long-term progression of the PD model.

The role of T-lymphocytes in central nervous system diseases.

The central nervous system (CNS) has been considered an immunologically privileged site. In the past few decades, research on inflammation in CNS diseases has mostly focused on microglia, innate immune cells that respond rapidly to injury and infection to maintain CNS homeostasis. Discoveries of lymphatic vessels within the dura mater and peripheral immune cells in the meningeal layer indicate that the peripheral immune system can monitor and intervene in the CNS. This review summarizes recent advances in the involvement of T lymphocytes in multiple CNS diseases, including brain injury, neurodegenerative diseases, and psychiatric disorders. It emphasizes that a deep understanding of the pathogenesis of CNS diseases requires intimate knowledge of T lymphocytes. Aiming to promote a better understanding of the relationship between the immune system and CNS and facilitate the development of therapeutic strategies targeting T lymphocytes in neurological diseases.

Performance and microbial response to nitrate nitrogen removal from simulated groundwater by electrode biofilm reactor with Ti/CNT/Cu5-Pd5 catalytic cathode.

To enhance the removal of nitrate nitrogen (NO3 - -N) in groundwater with a low C/N ratio, electrocatalytic reduction of NO3 - -N has received extensive attention since its electrons can be directly produced in situ while simultaneously providing a clean electronic donor of hydrogen for denitrifying bacteria. In this study, Ti/CNT/CuPd bimetallic catalytic electrodes with different copper-palladium (CuPd) ratios were prepared by electrodeposition onto carbon nanotube (CNT) using titanium (Ti) plates. The results showed that the NO3 - -N conversion rate by Ti/CNT/Cu5-Pd5 electrode was the highest (53.60%) compared with other CuPd electrode ratios because of the combined role of the copper's high NO3 - -N catalytic activity and the palladium's high N2 selectivity. A new type of electrode biofilm reactor (EBR) with Ti/CNT/Cu5-Pd5 cathode, biochar substrate was constructed to explore the removal ability of NO3 - -N in simulated low C/N groundwater. When the influent NO3 - -N concentration was 30 mg/L, under the condition of a 30 mA electronic current and hydraulic retention time (HRT) of 12 h, the removal rate of NO3 - -N could reach as high as 78.1 ± 1.2%, and the N2 conversion rate was 99.7%. The horizontal distribution of microbial communities in EBR showed that the denitrification capacity was significantly improved through the electrochemical catalytic reduction of the Ti/CNT/Cu5-Pd5 cathode and the supply of the hydrogen electron donor to autotrophic denitrogenerating microbes such as Anaerobacillus, Thauera, and Hydrophaga. This study provides a new bimetallic catalytic cathode to enhance the removal of NO3 - -N in groundwater with a low C/N ratio. PRACTITIONER POINTS: The Cu5Pd5/CNTs/Ti electrode is beneficial to the adsorption and reduction of NO3 - -N to N2 . The production of hydrogen electron donors by cathode promoted nitrogen degradation. Activated electrodes together with denitrifying microorganisms contributed to the improved N removal rate.

Identification of New Compounds against PRRSV Infection by Directly Targeting CD163.

The porcine reproductive and respiratory syndrome viruses (PRRSV) led to a global panzootic and huge economical losses to the pork industry. PRRSV targets the scavenger receptor CD163 for productive infection. However, currently no effective treatment is available to control the spread of this disease. Using bimolecular fluorescence complementation (BiFC) assays, we screened a set of small molecules potentially targeting the scavenger receptor cysteine-rich domain 5 (SRCR5) of CD163. We found that the assay examining protein-protein interactions (PPI) between PRRSV glycoprotein 4 (GP4) and the CD163-SRCR5 domain mainly identifies compounds that potently inhibit PRRSV infection, while examining the PPI between PRRSV-GP2a and the SRCR5 domain maximized the identification of positive compounds, including additional ones with various antiviral capabilities. These positive compounds significantly inhibited both types 1 and 2 PRRSV infection of porcine alveolar macrophages. We confirmed that the highly active compounds physically bind to the CD163-SRCR5 protein, with dissociation constant (KD) values ranging from 28 to 39 µM. Structure-activity-relationship (SAR) analysis revealed that although both the 3-(morpholinosulfonyl)anilino and benzenesulfonamide moieties in these compounds are critical for the potency to inhibit PRRSV infection, the morpholinosulfonyl group can be replaced by chlorine substituents without significant loss of antiviral potency. Our study established a system for throughput screening of natural or synthetic compounds highly effective on blocking of PRRSV infection and shed light on further SAR modification of these compounds. IMPORTANCE Porcine reproductive and respiratory syndrome virus (PRRSV) causes significant economic losses to the swine industry worldwide. Current vaccines cannot provide cross protection against different strains, and there are no effective treatments available to hamper the spread of this disease. In this study, we identified a group of new small molecules that can inhibit the PRRSV interaction with its specific receptor CD163 and dramatically block the infection of both types 1 and type 2 PRRSVs to host cells. We also demonstrated the physical association of these compounds with the SRCR5 domain of CD163. In addition, molecular docking and structure-activity relationship analyses provided new insights for the CD163/PRRSV glycoprotein interaction and further improvement of these compounds against PRRSV infection.

An Update on Peripheral Blood Extracellular Vesicles as Biomarkers for Parkinson's Disease Diagnosis.

Parkinson's disease (PD) is the world's second primary neurodegenerative disease, and the diagnosis and treatment of PD have become mainstream research. Over the past decades, several studies have identified potential biomarkers for diagnosing PD. Among them, extracellular vesicles (EVs) can carry specific biomarkers reflecting the physiological and pathological state of the body. Due to the blood-brain barrier (BBB) limitation, peripheral blood is limited in diagnosing neurodegenerative diseases. With the increasing research on EVs, their ability to pass through BBB indicated that peripheral blood could depict disease status like cerebrospinal fluid (CSF). Peripheral blood is a clinically available sample and has recently been widely used by researchers in various studies. In this review, we summarized previous studies on PD diagnosis biomarkers in peripheral blood EVs and evaluated their diagnostic value. Some EV surface markers were also described, which can extract EVs from specific cell origins. In addition, the combination of several biomarkers demonstrated good diagnostic performance in PD diagnosis compared with a single biomarker, suggesting the focus of future research.

Bisphenol A exposure causes testicular toxicity by targeting DPY30-mediated post-translational modification of PI3K/AKT signaling in mice.

Bisphenol A (BPA), one of the chemicals with the highest volume of production worldwide, has been demonstrated to cause testicular toxicity via different pathways. However, there is little evidence concerning the mechanism of BPA exposure induced histone modification alterations, especially regarding the effect on the histone H3 lysine 4 (H3K4) epigenetic modification. Our results demonstrated a new epigenetic regulation of BPA exposure on testicular damage using both cell culture and mouse models. With BPA treatment, disordered and shrunken seminiferous tubules and poor sperm quality were observed in vivo, and mouse spermatogonial germ cell proliferation was inhibited in vitro. BPA attenuated PI3K expression inducing phospho-AKT inhibition in vivo and in vitro. DPY30 was the only downregulated subunit in BPA and MEK2206 (AKT inhibitor) treated cells, which contributed to reducing H3K4me3 recruitment at the PIK3CA transcriptional start site (TSS) in BPA treated cells. The toxicity caused by BPA exposure was relieved after the transduction of adenoviruses expressing DPY30 transgenes, which resulted in the stimulation of PI3K/AKT with H3K4me3 enriched at the PI3KCA TSS. DPY30 promoted cell glycolysis via AMPK and proliferation through AKT/P21. DPY30 was mainly located in the round and elongated spermatids for energy accumulation in mature sperm in AD-DPY30-treated mice which showed higher sperm quality. Overall, our results indicated that BPA exposure causes testicular toxicity through a DPY30-mediated H3K4me3 epigenetic modification, which serves to regulate the PI3K/AKT/P21 pathway.

Hydrothermally assisted synthesis of nano zero-valent iron encapsulated in biomass-derived carbon for peroxymonosulfate activation: The performance and mechanisms for efficient degradation of monochlorobenzene.

A facile, green and easily-scalable method of synthesizing stable and effective nano zero-valent iron (nZVI)­carbon composites for peroxymonosulfate (PMS) activation was highly desirable for in-situ groundwater remediation. This study developed a two-step hydrothermally assisted carbothermal reduction method to prepare nZVI-encapsulated carbon composite (Fe@C) using rice straw and ferric nitrate as precursors. The hydrothermal reactions were conducive to iron loading, and carbothermal temperature was crucial for the aromatization and graphitization of hydrothermal carbonaceous products, the reductive transformation of iron oxides into nZVI and the development of porous structure in composites. At carbothermal temperature of 800 °C following hydrothermal reactions, the stable Fe@C800 with nZVI encapsulated in the spherical carbon shell was obtained and exhibited the best catalytic performance for PMS activation and the degradation of monochlorobenzene (MCB) in a wide range of pH values (3-11) with removal efficiency after 120 min reaction and first-order kinetic rate constant (k1) of 98.7% and 0.087 min-1 respectively under the optimum conditions of 10 mM PMS and 0.2 g·L-1 Fe@C800. The inhibiting effects of common co-existed anions (i.e., Cl-, HCO3- and H2PO4-) and humic acid in groundwater on the removal of MCB in Fe@C800/PMS system was also investigated. Both OH-dominated radical processes and nonradical pathways involving 1O2 and surface electron transfers were accounted for PMS activation and MCB removal. The inner nZVI was protected by the carbon shell, endowing Fe@C800 with high reactivity and good reusability. Additionally, 81.2% and 73.5% of MCB removal rates were achieved in tap water and actual contaminated groundwater respectively. This study not only provided a novel strategy to synthesize highly effective and stable nZVI­carbon composites using the agricultural biomass waste for PMS induced oxidation of organic contaminants in groundwater, but also enhanced the understanding on the activation mechanism of iron­carbon based catalysts towards PMS.

Preparation and Properties of Poly(ethylene glycol-co-cyclohexane-1,4-dimethanol terephthalate)/Polyglycolic Acid (PETG/PGA) Blends.

Polyglycolic acid (PGA) is used as a reinforcing component to enhance the mechanical properties of poly(ethylene glycol-co-cyclohexane-1,4-dimethanol terephthalate) (PETG). The tensile performance, micromorphology, crystallinity, heat resistance, and melt mass flow rates (MFRs) of PETG/PGA blends with varying PGA contents were studied. Both the tensile yield strength and tensile modulus of the PETG/PGA blends increased gradually with an increase in the PGA content from 0 to 35 wt%. The tensile yield strength of the PETG/PGA (65/35) blend increased by 8.7% (44.38 to 48.24 MPa), and the tensile modulus increased by 40.2% (1076 to 1509 MPa). However, its tensile ductility decreased drastically, owing to the poor interfacial compatibility of PETG/PGA and the oversized PGA domains. A multiple epoxy chain extender (ADR) was introduced into the PETG/PGA (65/35) blend to improve its interfacial compatibility and rheological properties. The tensile performance, micromorphology, rheological properties, crystallinity, and heat resistance of PETG/PGA (65/35) blends with varying ADR contents were studied. The strong chain extension effect of ADR along with its reactive compatibilization improved the rheological properties and tensile ductility. By carefully controlling the ADR concentration, the performance of PETG/PGA blends can be regulated for different applications.

Spatiotemporal differences in phosphorus release potential of bloom-forming cyanobacteria in Lake Taihu.

The abnormal elevation of cyanobacterial density and total phosphorus concentration after the reduction of exogenous pollutants in Lake Taihu is still an open question. An in-situ light-dark bottle method was used to investigate the spatiotemporal differences of phosphorus release potential of bloom-forming cyanobacteria (BFC) in Lake Taihu. Generalized additive model analysis (GAM) of field data revealed that the phosphorus release potential of BFC increased with the upregulation of Chlorophyll a (Chl-a) content per cell, which was further validated by the laboratory experiment results. We deduced that the accumulation of Chl-a content per cell might be an essential index of high phosphorus release potential of BFC. The phosphorus release potential of BFC was much higher in summer and autumn than that in spring and winter, while the phosphorus absorption potential increased with the rising of temperature. The distinct physiological status of BFC at different seasons brought about their variation in phosphorus release potential. Additionally, high phosphorus release potential of BFC region mainly concentrated in the eastern and the central, northwest, western, and the south of Lake Taihu in spring, summer, autumn, and winter, respectively. Further studies showed that the spatial differences in phosphorus release potential of BFC were most probably due to the horizontal drift of BFC driven by the prevailing wind. Collectively, the synergism of BFC's physiological status and horizontal drift determined the spatiotemporal differences of phosphorus release potential of BFC in Lake Taihu. Moreover, apparent spatiotemporal differences in phosphorus release potential of BFC were essential factors that induced the distinct distribution of total phosphorus in Lake Taihu. This study provides insight for exploring the reason for the constant increase of total dissolved phosphorus concentration and cyanobacterial density in Lake Taihu for the past 5 years.

Efficient nitrate removal by Pseudomonas mendocina GL6 immobilized on biochar.

The performance of nitrate removal by Pseudomonas mendocina GL6 cells immobilized on bamboo biochar was investigated. The results showed that immobilized bacterial cells performed better nitrate removal than the free bacterial cells, and the nitrate removal rate increased from 6.51 mg/(L·h) of free cells to 8.34 mg/(L·h) of immobilized cells. The nitrate removal of immobilized bacterial cells fitted well to the zero-order kinetics model. Moreover, bath experiments showed that immobilized bacterial cells displayed more nitrate removal capacity under different conditions than free bacterial cells due to the protection of biochar carrier. The subsequent mechanistic study suggested that biochar promoted the expression level of denitrification functional genes (napA and nirK) and electron transfer genes involved in denitrification (napB and napC), which resulted in the increase of nitrate removal efficiency. Thus, biochar-immobilized P. mendocina GL6 has much potential to remove nitrate from wastewater via aerobic denitrification.

Study on the experimental performance by electrolysis-integrated ecological floating bed for nitrogen and phosphorus removal in eutrophic water.

The new-type electrolysis-integrated ecological floating beds (EEFBs) were set up to study their water removal ability due to the excellent water treatment capacity of electrolysis, this enhanced EEFBs were made of polyethylene filled with biochar substrate and in middle of the substrate placed the Mg-Al alloy served as anode and graphite served as cathode. The results show that removal rates of total nitrogen (TN), ammonia nitrogen (NH3-N), total phosphorus (TP) and phosphate (PO43--P) by the EEFBs increased 53.1%, 96.5%, 76.5% and 74.5%, respectively. The electrolysis reaction was the main pathway for TN and TP removals in the EEFBs. A higher concentration of hydrogen autotrophic denitrification bacteria was recorded in the substrate of the EEFBs than that in the traditional ecological floating beds (EFBs) (p < 0.05), suggesting that the electrolysis may have enhanced the NO3--N removal efficiency of the EEFBs by promoting the growth and reproduce of hydrogen autotrophic denitrification bacteria. The in-situ formation of Mg2+ and Al3+ ions from a sacrificial Mg-Al alloy anode, caused PO43--P and other suspended matter flocculation, improved phosphorus removal and simultaneously reduced turbidity. Thus, electrolysis-integrated ecological floating bed has high nitrogen and phosphorus removal potential in eutrophic water.

Effects of Organic Montmorillonite (OMMT) and Pre-Orientation on Property of Poly(l-lactic acid) (PLLA)/Ethylene Propylene Diene Monomer (EPDM) Blends.

Poly(l-lactic acid)/ethylene propylene diene monomer/organic montmorillonite (PLLA/EPDM/OMMT) samples were melt-compounded and then processed into sheets via two routes, namely, compression-molding and calendering. Tensile performance, morphology, and thermal property of the samples were investigated. Tensile test showed that the incorporation of OMMT resulted in significant enhancement in the tensile ductility of the PLLA/EPDM samples. SEM observation revealed that EPDM domain size decreased largely with increasing OMMT loading, indicating the compatibility of OMMT with PLLA/EPDM blends. Moreover, the elongation at break, tensile yield strength, and modulus of the calendered samples were found to be much higher than those of the compression-molded samples. It can be attributed to the pre-oriented rigid amorphous fraction of PLLA matrix and pre-stretched EPDM phases in the calendered samples produced by the stretching/shearing effect of calendering. Compared to the spherical/ellipsoidal EPDM particles in the compression-molded samples, these stretched EPDM phases with higher aspect ratio in the calendered samples can be more effective to initiate craze, and terminate the craze growing to a crack along transversal direction. Therefore, the calendered samples show a better tensile ductility than the compression-molded ones. Moreover, annealing was carried out to increase the crystallinity of the samples. Tensile performance, morphology, and thermal property of the annealed samples were also systematically investigated.

The impact of heating season factors on eight PM2.5-bound polycyclic aromatic hydrocarbon (PAH) concentrations and cancer risk in Beijing.

In 2015, 443 atmospheric PM2.5 samples were collected at five sampling sites in Beijing. The concentrations of PM2.5-bound PAH8 (Chr, BaA, BbF, BkF, B[a]P, DBA, BghiP, and IND) were determined via high performance liquid chromatography (HPLC). The annual concentration of PM2.5-bound PAH8, lifetime cancer risk, and the increasing value due to heating season factors (heating and meteorological conditions) were analyzed. The results showed that the sum concentration of PM2.5-bound PAH8 during heating season was 72.6 ng/m3 and higher than the non-heating season concentration of 4.77 ng/m3. The annual concentration was 10.6 ng/m3, which increased 5.83 ng/m3 due to heating season factors. The B[a]P annual concentration was 1.67 ng/m3 and higher than the limit of 1 ng/m3, which was 15.2 times that of non-heating season. Diesel vehicles and gasoline vehicles were the primary PAH8 sources during non-heating season, while the mixed sources of diesel vehicles, gasoline vehicles, and combustion were the dominant PAH8 sources during heating season. The most significant health hazard pollutant was B[a]P, which accounted for 72%, 74%, and 69% of the B[a]P equivalent concentration (B[a]Peq) of PAH8 during heating season, non-heating season, and throughout 2015, respectively. The lifetime cancer risk was 2.67 × 10-6, which increased 1.36 × 10-6 due to heating season factors. Therefore, heating season factors nearly doubled the annual concentration of PM2.5-bound ∑PAH8 and lifetime cancer risk. The results indicated that to protect human health, it is very important to control PM2.5-bound ∑PAH8 emissions during heating season, especially B[a]P emissions.

The Mechanism of Rap1 Regulates N-cadherin to Control Neuronal Migration.

Rap1 and N-cadherin regulate glia-independent translocation of cortical neurons. It remains unclear how Rap1 regulates N-cadherin-mediated neuronal migration. Here, we overexpressed Rap1gap in mouse brains (embryonic day 16) to inactivate Rap1, and observed that neurons did not migrate to the outer layer. We confirmed that Rap1 was involved in the regulation of late neurons in vivo. Rap1gap overexpression and Rap1 suppression in CHO cells decreased the expression of cytoskeletal proteins such as tubulin. Changes in the expression of cell morphology regulators, such as N-cadherin and ß-catenin, were also observed. Inhibition of N-cadherin in mouse brains prevented neuronal migration to the outer layer. The morphology of CHO cells was changed after overexpression of Rap1gap. We propose that Rap1 regulates the expression of N-cadherin during embryonic development, which affects ß-catenin expression. Beta-catenin in turn regulates cytoskeletal protein expression, ultimately affecting neuronal morphology and migration.

Characterization of Aerobic Denitrifying Bacterium Pseudomonas mendocina Strain GL6 and Its Potential Application in Wastewater Treatment Plant Effluent.

To remove nitrate in wastewater treatment plant effluent, an aerobic denitrifier was newly isolated from the surface flow constructed wetland and identified as Pseudomonas mendocina strain GL6. It exhibited efficient aerobic denitrification ability, with the nitrate removal rate of 6.61 mg (N)·L-1·h-1. Sequence amplification indicated that the denitrification genes napA, nirK, norB, and nosZ were present in strain GL6. Nitrogen balance analysis revealed that approximately 74.5% of the initial nitrogen was removed as gas products. In addition, the response surface methodology experiments showed that the maximum removal of total nitrogen occurred at pH 7.76, C/N ratio of 11.2, temperature of 27.8 °C, and with shaking at 133 rpm. Furthermore, under the optimized cultivation condition, strain GL6 was added into wastewater treatment plant effluent and the removal rates of nitrate nitrogen and total nitrogen reached 95.6% and 73.6%, respectively. Thus, P. mendocina strain GL6 has high denitrification potential for deep improvement of effluent quality.