Single-frequency DBR lasing by integrating FBGs into germanium-free photosensitive highly Yb3+-doped silica fibers.

Monolithic distributed Bragg reflector (DBR) cavity which directly integrates fiber Bragg gratings (FBGs) into the photosensitive RE-doped fibers is a promising configuration in constructing compact and efficient single frequency fiber lasers (SFFLs). Yet, the doping level of rare-earth (RE) ions has generally to be sacrificed in the classical Ge-photosensitized RE-doped silica fibers because of the dramatic refractive index increase caused by the introduction of Ge. Here, we demonstrate an approach to realize the trade-off between photosensitivity and RE doping concentration. We validate that the addition of a small amount of cerium (0.37wt.%) instead of Ge could photosensitize Yb3+-doped silica fiber (YDF), while maintaining fiber numerical aperture (NA) at 0.12 under a high 2.5-wt.% Yb doping level. Based on the short monolithic DBR cavity constructed by this germanium-free photosensitive highly YDF, a 1064 nm fiber laser with a 48.6% slope efficiency and an over 200 mW power on two orthogonally polarized modes could be realized. Further stable and linear-polarized 1064 nm SFFL is also demonstrated in a designed monolithic polarization maintaining cavity with an output power of 119 mW and an efficiency of 26.4%. Our results provide an alternative way to develop photosensitive highly RE-doped fibers towards monolithic laser cavity application.

Phage cocktail superimposed disinfection: A ecological strategy for preventing pathogenic bacterial infections in dairy farms.

Bovine mastitis (BM) is mainly caused by bacterial infection that has a highly impact on dairy production, affecting both economic viability and animal well-being. A cross-sectional study was conducted in dairy farms to investigate the prevalence and antimicrobial resistance patterns of bacterial pathogens associated with BM. The analysis revealed that Staphylococcus (49%), Escherichia (16%), Pseudomonas (11%), and Klebsiella (6%) were the primary bacterial pathogens associated with mastitis. A significant proportion of Staphylococcus strains displayed multiple drug resistance. The use of disinfectants is an important conventional measure to control the pathogenic bacteria in the environment. Bacteriophages (Phages), possessing antibacterial properties, are natural green and effective disinfectants. Moreover, they mitigate the risk of generating harmful disinfection byproducts, which are commonly associated with traditional disinfection methods. Based on the primary bacterial pathogens associated with mastitis in the investigation area, a phage cocktail, named SPBC-SJ, containing seven phages capable of lysing S. aureus, E. coli, and P. aeruginosa was formulated. SPBC-SJ exhibited superior bactericidal activity and catharsis effect on pollutants (glass surface) compared to chemical disinfectants. Clinical trials confirmed that the SPBC-SJ-based superimposed disinfection group (phage combined with chemical disinfectants) not only cut down the dosage of disinfectants used, but significantly reduced total bacterial counts on the ground and in the feeding trough of dairy farms. Furthermore, SPBC-SJ significantly reduced the abundance of Staphylococcus and Pseudomonas in the environment of the dairy farm. These findings suggest that phage-based superimposed disinfection is a promising alternative method to combat mastitis pathogens in dairy farms due to its highly efficient and environmentally-friendly properties.

Development and mouse model evaluation of a new phage cocktail intended as an alternative to antibiotics for treatment of Staphylococcus aureus-induced bovine mastitis.

Bovine mastitis (BM) is a prevalent infectious disease in dairy herds worldwide, resulting in substantial economic losses. Staphylococcus aureus is a major cause of mastitis in animals, and its antibiotic resistance poses challenges for treatment. Recently, there has been a renewed interest in the development of alternative methods to antibiotic therapy, including bacteriophages (phages), for controlling bacterial infections. In this study, 2 lytic phages (designated as JDYN for vB_SauM_JDYN and JDF86 for vB_SauM_JDF86) were isolated from the cattle sewage effluent samples collected from dairy farms in Shanghai. The 2 phages have a broad bactericidal spectrum against Staphylococcus of various origins. Genomic and morphological analyses revealed that the 2 phages belonged to the Myoviridae family. Moreover, JDYN and JDF86 remained stable under a wide range of temperatures or pH and were almost unaffected in chloroform. In this study, we prepared a phage cocktail designated "PHC-1" which consisted of a 1:1:1 ratio of JDYN, JDF86 and SLPW (a previously characterized phage). PHC-1 showed the strongest bacteriolytic effect and the lowest frequency of emergence of bacteriophage insensitive mutants compared with monophages. The bovine mammary epithelial cells (MAC-T cells) and lactating mice mastitis model were used to evaluate the effectiveness of PHC-1 in vitro and in vivo, respectively. The results demonstrated that PHC-1 treatment significantly reduced bacterial load, alleviated inflammatory response, and improved mastitis pathology. Altogether, these results suggest that PHC-1 has the potential to treat S. aureus-induced bovine mastitis and that phage cocktails can combat antibiotic-resistant S. aureus infections.

Novel modified semi-carbonized fiber prepared using discarded clothes for derisking Cu(II) and Pb(II) contaminated water.

We report a novel modified semi-carbonized fiber (CF) prepared using cotton and acrylic clothes for derisking contaminated water to realize the resource utilization of discarded clothes in wastewater treatment. In this study, amphoteric and auxiliary modifiers were used to modify CFs for preparing amphoteric and amphoteric-auxiliary CFs. The basic physicochemical properties of different modified CFs were determined, and the microscopic morphology of modified CFs was detected. The isothermal adsorption characteristics of Cu(II) and Pb(II) on different modified CFs were investigated by the batch method, and the effect mechanisms of temperature, pH, ionic strength, and material dose were compared. Physicochemical properties and microscopic morphology results proved that amphoteric and auxiliary modifiers were modified on the CF surface and changed the surface properties of CF. The adsorption capacities of Cu(II) and Pb(II) on modified CFs increased with the increase in equilibrium concentration of Cu(II) and Pb(II), and the isotherm was more suitable for Freundlich model fitting than that of the Langmuir model. The maximum adsorption capacities (qm) of Cu(II) and Pb(II) on different modified CFs were 60.72-81.26 mg/g and 102.58-161.72 mg/g, respectively, and presented the trend of amphoteric-auxiliary CFs > amphoteric CFs > CFs. Increasing pH and temperature and decreasing ionic strength and material dose were beneficial to Cu(II) and Pb(II) adsorption. The Cu(II) and Pb(II) adsorption process was a spontaneous, endothermic, and entropy-increasing reaction, and the adsorption rate was controlled by chemisorption. The adsorption amount of amphoteric-auxiliary CFs maintained about 65% of original materials after 3 times of regeneration. Electrostatic attraction, precipitation, complexation, and ion exchange were the main adsorption mechanisms. The cation exchange capacity and total pore volume of modified CFs were key to determining qm of Cu(II) and Pb(II).

High ytterbium concentration Yb/Al/P/Ce co-doped silica fiber for 1-µm ultra-short cavity fiber laser application.

We demonstrate a high ytterbium concentration Yb/Al/P/Ce co-doped silica fiber by conventional modified chemical vapor deposition (MCVD) technology and solution doping process. The fiber has a Yb concentration of about 2.5 wt%, and the corresponding core absorption coefficient is measured to be ∼1400 dB/m at 976 nm. The gain coefficient was measured to be approximately 1.0 dB/cm. It is found that the Yb/Al/P/Ce co-doped silica shows a lower photodarkening-induced equilibrium loss of 52 dB/m at 633 nm than the Yb/Al/P co-doped silica fiber of 117 dB/m. Using the heavily Yb3+-doped silica fiber, a compact and robust ultrashort cavity single-frequency fiber laser was achieved with a maximum output power of 75 mW and a linewidth of 14 kHz. Furthermore, a compact passively mode-locked fiber laser (MLFL) with a repetition rate of 1.23 GHz was also proposed using our developed Yb-doped fiber. The laser properties of the proposed lasers were systematically investigated, demonstrating the superior performance of this fiber in terms of photodarkening resistance and ultrashort-cavity laser application. Furthermore, utilizing an all-fiber structure based on silica-based fiber offers the significant advantage of high stability and reliability.

First Report of Lasiodiplodia pseudotheobromae Causing Postharvest Fruit Rot on Indian Jujube in China.

Indian jujube (Ziziphus mauritiana Lamarck), is one of the most popular fruit crops in South China. In March 2023, a fruit rot of indian jujube with about 5% disease incidence was observed in two supermarkets of Nanchang City, Jiangxi Province, China. Initially, the symptoms appeared as slightly brown spots on the fruit surface, with disease progression, the lesions gradually expanded and covered with a layer of hyphae. Small pieces (3 to 4 mm2) from the periphery of 15 diseased fruit were surface disinfected using 1% sodium hypochlorite for 30 s, rinsed three times in sterilized distilled water, air dried, and then aseptically placed onto potato dextrose agar (PDA) media and incubated at 25°C for three days. A total of ten single spore isolates with similar morphology were obtained. Colonies of these consisted of initially white, gradually turning gray and eventually becoming black, and aerial hyphae were dense and fluffy. Conidiogenous cells were smooth, hyaline, cylinder-shaped, and holoblastic. Conidia were ellipsoidal, top and base-rounded, and thick-walled, immature conidia were colorless, hyaline, and aseptate, compared with dark brown color of the mature conidia, which were one-septate with longitudinal striations, ranging in size from 22.8 to 31.8 (mean 27.6) µm in length and 12.2 to 20 (mean 14.6) µm in width. The morphological characteristics were consistent with the characteristics of the Lasiodiplodia species (Phillips et al. 2013). To accurately identify the strain, three representative isolates, namely JFRL 03-1147, JFRL 03-1148, and JFRL 03-1149, were selected for further identification. The internal transcribed spacers (ITS), translation elongation factor 1-alpha (TEF1-α), and beta-tubulin (TUB2) genes/regions were amplified and sequenced using primers ITS1/ITS4, EF1-688F/EF1-1251R, and Bt2a/Bt2b, respectively (Chen et al. 2021). These nucleotide sequences were deposited in GenBank with accession numbers OQ804425-OQ804427 (ITS), OQ818097-OQ818099 (TEF1-α), and OQ818100-OQ818102 (TUB2). A BLASTn homology search for these nucleotides showed 99-100% identity to ITS (EF622077, 487 nt/487 nt), TEF1-α (EF622057, 306 nt/307 nt) and TUB2 (EU673111, 434 nt/434 nt) sequences of Lasiodiplodia pseudotheobromae CBS 116459 (ex-type). The maximum likelihood analyses were performed for the combined ITS, TEF1-α and TUB2 data set using IQtree web server (Trifinopoulos et al. 2016). The phylogenetic tree showed that the three isolates clustered with Lasiodiplodia pseudotheobromae in a clade with 99% bootstrap support. Therefore, the fungus was identified as L. pseudotheobromae based on morphological and molecular characteristics. To evaluate pathogenicity, 4 healthy fruits of indian jujube were surface sterilized with 75% ethanol and wounded by sterile needle, and a 5-mm-diameter agar with 5-days-old mycelium of the isolate JFRL 03-1148 cultured on PDA at 25°C was put on the wound. Another set of 4 fruits was inoculated with sterile agar plugs as controls. The fruits were cultured at 25℃ and 85% relative humidity, and the test was repeated twice. These fruits inoculated with L. pseudotheobromae showed similar rot symptoms after 3 days, while the control group remained asymptomatic. To fulfill Koch's postulates, the pathogen was re-isolated from the inoculated fruits and confirmed as L. pseudotheobromae by morphological and molecular analysis. L. pseudotheobromae has previously been reported causing fruit rot on citrus, mango and papaya (Alam et al. 2021; Chen et al. 2021; Netto et al. 2014). But to our knowledge, this is the first report of L. pseudotheobromae caused postharvest fruit rot on indian jujube in China. Therefore, managers should pay more attention to postharvest fruit rot disease caused by L. pseudotheobromae, and formulate appropriate disease control measures to reduce its losses.

Whey protein isolate attenuates depression-like behavior developed in a mouse model of breast tumor.

Increasing evidence indicates that tryptophan (Trp) metabolism disturbance controls hippocampal 5-hydroxytryptamine (5-HT) and thereby affecting depression-like behavior, in which the gut microbiota (GM) might be involved. This study investigated the effect of Trp-rich whey protein isolate (WPI) on depressive-like behavior in 4T1 tumor-bearing mice. Female BALB/c mice were subcutaneously inoculated with murine 4T1 mammary carcinoma cells and received 2 g/kg of WPI by gavage daily for 21 days. The results showed that WPI exerted no significant effects on tumor weight and volume, but abrogated tumor-induced depression-like behavior, as evidenced by remarkably increased time and distance in the center of the open-field test, decreased immobility time in the tail suspension test, increased time and number of entries to the open arms in the elevated plus maze and sucrose preference. Moreover, WPI promoted the hippocampal Trp, 5-hydroxytryptophan (5-HTP), 5-HT, 5-hydroxyindoleacetic acid (5-HIAA) levels and inhibited kynurenine (Kyn) through up-regulating serotonin transporter (SERT) and down-regulating indoleamine 2, 3-dioxygenase (IDO). WPI showed an enriched microbial diversity indicated by increased Shannon index and decreased Simpson index, reduced the abundances of Proteobacteria, Rikenellaceae_RC9_gut_group, Alloprevotella and Prevotellaceae_UCG-001, and increased the abundance of unclassified_k__norank_d__Bacteria in tumor-bearing mice (P < 0.05). At level 3, WPI enhanced the function of microbial gene related to Trp metabolism in the KEGG pathways (P < 0.05). Our results suggest that WPI exhibits a potent antidepressant-like effect via the regulation of hippocampal Trp metabolism and alteration of GM composition and function, and it may be an effective prevention for cancer-related depression.

Risk factors for transplant-associated thrombotic microangiopathy (TA-TMA): a systematic review and meta-analysis.

INTRODUCTION: Transplant-associated thrombotic microangiopathy (TA-TMA) is a severe hematopoietic stem cell transplantation complication with high mortality and a poor patient prognosis. The pathogenesis of TA-TMA is not yet clear. In previous studies, the conclusions of different centers remain controversial. We conducted a systematic review and meta-analysis of nine selected risk factors that might be associated with the onset of TA-TMA. MATERIALS AND METHODS: PubMed databases were searched from their inception up to 15 September 2021, for relevant studies. The articles included unprocessed data related to one or more of the risk factors discussed in this meta-analysis, including recipient gender, donor type, graft source, pretreatment, infection, aGVHD, diagnosis, total body irradiation (TBI), and CMV infection. The outcome is the incidence rate (IR) of TA-TMA. RESULTS AND CONCLUSIONS: According to the sixteen articles included, risk factors included in this Meta-analysis included gender, unrelated donor source (95% CI: 1.29-2.01), graft source from peripheral blood stem cell (PBSC)(95% CI: 0.48-0.97), RIC/NMA, class II-IV aGVHD (95% CI: 2.22-4.78), nonmalignant disease, TBI. However, inconsistent diagnostic criteria for TA-TMA and the limited number of studies have an impact on the results of the study. More prospective cohort studies and More accurate diagnostic criteria are needed.

First Report of Brown Rot Caused by Phytophthora nicotianae on Navel Orange Fruit in China.

Navel orange (Citrus sinensis Osbeck cv. Newhall) is widely planted in southern China. From September to November 2021, severe outbreaks of Phytophthora brown rot were observed on navel orange fruit in three local orchards in Ganzhou City (28.80N, 115.53E), Jiangxi Province, China, with a disease incidence of 25 to 35%. Symptomatic fruit was mostly observed 1-m from the ground. Initial symptoms on infected fruit were circular, pale-brown to brown, water-soaked, slightly sunken lesions, covered with sparse white mycelia-like growth. As the disease progressed, the lesions turned dark brown and enlarged on the fruit surface. Three to four infected fruits were randomly collected from each orchard, placed in transparent plastic bags and immediately brought back to the laboratory for isolations. Infected fruits were surface-disinfested with 70% ethanol for 60 sec, and rinsed three times with sterile water. Symptomatic tissues from the margin between necrotic and healthy tissues were cut into 5 mm × 5 mm pieces, placed onto potato dextrose agar and incubated at 28°C for 5 days. Nine isolates were obtained. Colonies of three isolates (JFRL 03-16, 03-18, 03-19) in 10-day-old 20% V8 juice agar consisted of abundant, white, cottony aerial mycelia. Hyphal swellings and coenocytic mycelium were observed. Sporangia were ovoid, ellipsoid to spherical, papillate, and ranged in size from 17.2 to 60.1 µm × 15.8 to 48.6 µm (x ̅=46.2 ± 5.5 × 32.4 ± 4.8 µm, n=50). Chlamydospores were spherical, suborbicular, and ranged from 17.8 to 45.9 µm diam (x ̅=30.5 ± 3.5 µm, n=50). Oospores were not observed in pure cultures. These morphological characteristics were consistent with those of P. nicotianae (LaMondia et al. 2014). Genomic DNA was extracted from a representative isolate, JFRL 03-18, using the NuClean Plant Genomic DNA kit (CWBIO, China). The internal transcribed spacer (ITS) region, ras-related protein ypt1 (YPT), ß-tubulin (TUB) gene were amplified by Polymerase Chain Reaction using primers ITS1/ITS4 (White et al. 1990), Yph1F/Yph2R (Schena et al. 2008), and TUBUF2/TUBUR1 (Kroon et al. 2004), respectively. All sequences were deposited in GenBank (Accession Nos. ON231777 for ITS, ON246910 for YPT, ON246908 for TUB). BLASTN homology search for these nucleotide sequences showed 100% identical to the ITS (MH341621), YPT (MK058408), TUB (MH760160) sequences of P. nicotianae. Sequences of twelve Phytophthora species and Pythium ostracodes were downloaded from GenBank. The phylogenetic tree of combined ITS, YPT, TUB sequences showed that the isolate JFRL 03-18 clustered with P. nicotianae. To complete Koch's postulates, zoospore suspensions were prepared from the cultures grown on 10-day-old V8 juice agar of isolates (JFRL 03-16, 03-18, 03-19). Pathogenicity tests were performed on healthy and surface-disinfested navel orange fruit. Nine fruits were gently wounded with a needle, inoculated with 10 µl zoospore suspension (104 zoospores/ml) of three isolates separately, and three fruit treated with sterilized water as controls. All fruit were incubated at 25℃ with 80% relative humidity and the test was repeated three times. After 7 days of incubation, the fruit inoculated with P. nicotianae showed similar brown rot symptoms and the control fruit remained symptomless. The pathogen was re-isolated from all inoculated fruits and confirmed as P. nicotianae by morphological and molecular analysis. Phytophthora nicotianae was previously reported on Hamlin sweet orange (Citrus sinensis (L.) Osbeck) fruit causing Phytophthora brown rot in Florida (Graham and Timmer 1995; Hao et al. 2018). To our knowledge, this is the first report of P. nicotianae causing Phytophthora brown rot of navel orange fruit in China. Based on the severity of this disease, local growers should develop and implement integrated disease management strategies for control.

Effect mechanism of litter extract from Alternanthera philoxeroides on the selective absorption of heavy metal ions by amphoteric purple soil.

Plant litter causes a serious waste of resources. Thus, plant litter extract (LE) should be used in the soil remediation of heavy metals. In this study, different proportions of LE from the Alternanthera philoxeroides were used to modify dodecyl dimethyl betaine (BS)-modified purple soil (P). The basic physicochemical properties of LE + BS-modified Ps (LE + BS-Ps) were determined, and the microscopic morphology of LE + BS-Ps was studied by using scanning electron microscopy (SEM), energy dispersion spectroscopy (EDS), Fourier transform infrared (FTIR) spectroscopy, and specific surface area detection. The isothermal adsorption characteristics of heavy metal ions (Pb2+, Cu2+, and Cr6+) on different LE + BS-Ps were investigated by the batch method, and the effect mechanisms of temperature, pH, ionic strength, and LE + BS-P's property were compared. Results showed that the cation exchange capacity and specific surface area of LE + BS-Ps increased, pH of LE + BS-Ps decreased, and TOC of LE + BS-Ps increased first and then decreased with increasing proportion of LE. FTIR, SEM, and EDS results proved that LE was modified on the surface of BS-P. Langmuir and Freundlich models could be used to describe the adsorption isotherms of heavy metal ions on different LE + BS-Ps, and the fitting correlation of the Langmuir model was higher than that of the Freundlich model. The maximum adsorption capacity (qm) of Pb2+, Cu2+, and Cr6+ were 107.60-295.66, 133.00-342.11, and 33.59-75.41 mmol/kg, respectively. The qm of Pb2+, Cu2+, and Cr6+ on LE + BS-Ps all increased first and then decreased with increasing proportion of LE, and the peak value was observed in 20%LE + BS-Ps. High pH improved Pb2+ and Cu2+ adsorption but inhibited Cr6+ adsorption. The adsorption amounts of Pb2+, Cu2+, and Cr6+ all increased first and then decreased with incresing ionic strength and were maintained at the maximum value of 0.1-0.2 mol/L. The Pb2+, Cu2+, and Cr6+ adsorption mechanisms on different LE + BS-Ps showed a positive temperature effect and presented spontaneous, exothermic and entropy-adding processes.

Bacteriophage Cocktails Protect Dairy Cows Against Mastitis Caused By Drug Resistant Escherichia coli Infection.

Mastitis caused by Escherichia coli (E. coli) remains a threat to dairy animals and impacts animal welfare and causes great economic loss. Furthermore, antibiotic resistance and the lagged development of novel antibacterial drugs greatly challenge the livestock industry. Phage therapy has regained attention. In this study, three lytic phages, termed vB_EcoM_SYGD1 (SYGD1), vB_EcoP_SYGE1 (SYGE1), and vB_EcoM_SYGMH1 (SYGMH1), were isolated from sewage of dairy farm. The three phages showed a broad host range and high bacteriolytic efficiency against E. coli from different sources. Genome sequence and transmission electron microscope analysis revealed that SYGD1 and SYGMH1 belong to the Myoviridae, and SYGE1 belong to the Autographiviridae of the order Caudovirales. All three phages remained stable under a wide range of temperatures or pH and were almost unaffected in chloroform. Specially, a mastitis infected cow model, which challenged by a drug resistant E. coli, was used to evaluate the efficacy of phages. The results showed that the cocktails consists of three phages significantly reduced the number of bacteria, somatic cells, and inflammatory factors, alleviated the symptoms of mastitis in cattle, and achieved the same effect as antibiotic treatment. Overall, our study demonstrated that phage cocktail may be a promising alternative therapy against mastitis caused by drug resistant E. coli.

Phage vB_PaeS-PAJD-1 Rescues Murine Mastitis Infected With Multidrug-Resistant Pseudomonas aeruginosa.

Pseudomonas aeruginosa is a Gram-negative pathogen that causes a variety of infections in humans and animals. Due to the inappropriate use of antibiotics, multi-drug resistant (MDR) P. aeruginosa strains have emerged and are prevailing. In recent years, cow mastitis caused by MDR P. aeruginosa has attracted attention. In this study, a microbial community analysis revealed that P. aeruginosa could be a cause of pathogen-induced cow mastitis. Five MDR P. aeruginosa strains were isolated from milk diagnosed as mastitis positive. To seek an alternative antibacterial agent against MDR, P. aeruginosa, a lytic phage, designated vB_PaeS_PAJD-1 (PAJD-1), was isolated from dairy farm sewage. PAJD-1 was morphologically classified as Siphoviridae and was estimated to be about 57.9 kb. Phage PAJD-1 showed broad host ranges and a strong lytic ability. A one-step growth curve analysis showed a relatively short latency period (20 min) and a relatively high burst size (223 PFU per infected cell). Phage PAJD-1 remained stable over wide temperature and pH ranges. Intramammary-administered PAJD-1 reduced bacterial concentrations and repaired mammary glands in mice with mastitis induced by MDR P. aeruginosa. Furthermore, the cell wall hydrolase (termed endolysin) from phage PAJD-1 exhibited a strong bacteriolytic and a wide antibacterial spectrum against MDR P. aeruginosa. These findings present phage PAJD-1 as a candidate for phagotherapy against MDR P. aeruginosa infection.

UPLC-MS-Based Serum Metabolomics Reveals Potential Biomarkers of Ang II-Induced Hypertension in Mice.

Hypertension is caused by polygenic inheritance and the interaction of various environmental factors. Abnormal function of the renin-angiotensin-aldosterone system (RAAS) is closely associated with changes in blood pressure. As an essential factor in the RAAS, angiotensin II (Ang II) contributes to vasoconstriction and inflammatory responses. However, the effects of overproduction of Ang II on the whole body-metabolism have been unclear. In this study, we established a hypertensive mouse model by micro-osmotic pump perfusion of Ang II, and the maximum systolic blood pressure reached 140 mmHg after 2 weeks. By ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry, the metabolites in the serum of hypertensive model and control mice were analyzed. Partial least squares discriminant analysis (PLS-DA) in both positive and negative ionization modes showed clear separation of the two groups. Perfusion of Ang II induced perturbations of multiple metabolic pathways in mice, such as steroid hormone biosynthesis and galactose metabolism. Tandem mass spectrometry revealed 40 metabolite markers with potential diagnostic value for hypertension. Our data indicate that non-targeted metabolomics can reveal biochemical pathways associated with Ang II-induced hypertension. Although researches about the clinical use of these metabolites as potential biomarkers in hypertension is still needed, the current study improves the understanding of systemic metabolic response to sustained release of Ang II in hypertensive mice, providing a new panel of biomarkers that may be used to predict blood pressure fluctuations in the early stages of hypertension.

Role of Transient Receptor Potential Vanilloid 4 in Vascular Function.

Transient receptor potential vanilloid 4 (TRPV4) channels are widely expressed in systemic tissues and can be activated by many stimuli. TRPV4, a Ca2+-permeable cation channel, plays an important role in the vasculature and is implicated in the regulation of cardiovascular homeostasis processes such as blood pressure, vascular remodeling, and pulmonary hypertension and edema. Within the vasculature, TRPV4 channels are expressed in smooth muscle cells, endothelial cells, and perivascular nerves. The activation of endothelial TRPV4 contributes to vasodilation involving nitric oxide, prostacyclin, and endothelial-derived hyperpolarizing factor pathways. TRPV4 activation also can directly cause vascular smooth muscle cell hyperpolarization and vasodilation. In addition, TRPV4 activation can evoke constriction in some specific vascular beds or under some pathological conditions. TRPV4 participates in the control of vascular permeability and vascular damage, particularly in the lung capillary endothelial barrier and lung injury. It also participates in vascular remodeling regulation mainly by controlling vasculogenesis and arteriogenesis. This review examines the role of TRPV4 in vascular function, particularly in vascular dilation and constriction, vascular permeability, vascular remodeling, and vascular damage, along with possible mechanisms, and discusses the possibility of targeting TRPV4 for therapy.

TLR4 Agonist Combined with Trivalent Protein JointS of Streptococcus suis Provides Immunological Protection in Animals.

Streptococcus suis (S. suis) serotype 2 (SS2) is the causative agent of swine streptococcosis and can cause severe diseases in both pigs and humans. Although the traditional inactive vaccine can protect pigs from SS2 infection, novel vaccine candidates are needed to overcome its shortcomings. Three infection-associated proteins in S. suis-muramidase-released protein (MRP), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), and DLD, a novel putative dihydrolipoamide dehydrogenase-have been previously identified by immunoproteomic assays. In this study, the effective immune protection of the recombinant trivalent protein GAPDH-MRP-DLD (JointS) against SS2, SS7, and SS9 was determined in zebrafish. To improve the immune efficacy of JointS, monophosphoryl lipid A (MPLA) as a TLR4 agonist adjuvant, which induces a strong innate immune response in the immune cells of mice and pigs, was combined with JointS to immunize the mice. The results showed that immunized mice could induce the production of a high titer of anti-S. suis antibodies; as a result, 100% of mice survived after SS2 infection. Furthermore, JointS provides good protection against virulent SS2 strain infections in piglets. Given the above, there is potential to develop JointS as a novel subunit vaccine for piglets to prevent infection by SS2 and other S. suis serotypes.

Puerarin induces mouse mesenteric vasodilation and ameliorates hypertension involving endothelial TRPV4 channels.

Puerarin (Pue) is an isoflavone derived from the root of Pueraria lobata, which has been widely used as food and a herb for treating cardiovascular and cerebrovascular diseases. Transient receptor potential vanilloid 4 (TRPV4), a Ca2+-permeable channel with multiple modes of activation, plays an important role in vascular endothelial function and vasodilation. However, no reports have shown the effects of Pue on TRPV4 channels and mouse small mesenteric arteries. In the present study, we performed a molecular docking assay by using Discovery Studio 3.5 software to predict the binding of Pue to TRPV4 protein. The activation of TRPV4 by Pue was determined by intracellular Ca2+ concentration ([Ca2+]i), live-cell fluorescent Ca2+ imaging and patch clamp assays. Molecular docking results indicated a high possibility of Pue-TPRV4 binding. [Ca2+]i and Ca2+ imaging assays showed that Pue activated TRPV4 channels and increased [Ca2+]i in TRPV4-overexpressing HEK293 (TRPV4-HEK293) cells and primary mouse mesenteric artery endothelial cells (MAECs). Patch clamp assay demonstrated that Pue stimulated the TRPV4-mediated cation currents. Additionally, Pue relaxed mouse mesenteric arteries involving the TRPV4-small-conductance Ca2+-activated K+ channel (SKCa)/intermediate-conductance Ca2+-activated K+ channel (IKCa) pathway, and reduced systolic blood pressure (SBP) in high-salt-induced hypertensive mice. Our study found for the first time that Pue acts as a TRPV4 agonist, induces endothelium-dependent vasodilation in mouse mesenteric arteries, and attenuates blood pressure in high-salt-induced hypertensive mice, highlighting the beneficial effect of Pue in treating endothelial dysfunction-related cardiovascular diseases.

Catalytic Dehydrochlorination of 1,2-Dichloroethane into Vinyl Chloride over Nitrogen-Doped Activated Carbon.

The pyrolysis of 1,2-dichloroethane (EDC) is the most popular commercialized way of producing vinyl chloride monomers (VCM); however, it is plagued by high-energy consumption and the resulting coke formation. Here, a series of nitrogen-doped (N-doped) activated carbon catalysts (N-AC) were prepared conveniently for EDC dehydrochlorination. The structural and textural properties of N-doped catalysts were characterized by X-ray diffraction, transmission electron microscopy, Raman spectra, temperature-programmed desorption of VCM and EDC, and X-ray photoelectron spectroscopy. The results revealed that doping N into activated carbon supports introduced basicity sites and caused partial graphitization on the catalyst surfaces. Thus, an improved absorption capacity to EDC and VCM and an accelerated desorption rate were obtained, which greatly enhanced EDC conversion and VCM selectivity. EDC was almost completely dehydrochlorided into vinyl chloride at a temperature of 300 °C and an EDC liquid hourly space velocity of 0.313 h-1. The high catalytic activity and selectivity as well as good stability suggested that the N-AC catalyst would be a promising dehydrochlorination catalyst on an industrial scale.

Immunity induced by recombinant attenuated IHNV (infectious hematopoietic necrosis virus)-GN438A expresses VP2 gene-encoded IPNV (infectious pancreatic necrosis virus) against both pathogens in rainbow trout.

Infectious hematopoietic necrosis virus (IHNV) and infectious pancreatic necrosis virus (IPNV) are important pathogens in rainbow trout farming worldwide. Their co-infection is also common, which causes great economic loss in juvenile salmon species. Development of a universal virus vaccine providing broadly cross-protective immunity will be of great importance. In this study, we generated two recombinant (r) virus (rIHNV-N438A-ΔNV-EGFP and rIHNV-N438A-ΔNV-VP2) replacing the NV gene of the backbone of rIHNV at the single point mutation at residue 438 with an efficient green fluorescent protein (EGFP) reporter gene and antigenic VP2 gene of IPNV. Meanwhile, we tested their efficacy against the wild-type (wt) IHNV HLJ-09 virus and IPNV serotype Sp virus challenge. The relative per cent survival rates of two recombinant viruses against (wt) IHNV HLJ-09 virus challenge were 84.6% and 81.5%, respectively. Simultaneously, the relative per cent survival rate of rIHNV-N438A-ΔNV-VP2 against IPNV serotype Sp virus challenge was 88.9%. It showed the two recombinant viruses had high protection rates and induced a high level of antibodies against IHNV or IPNV. Taken together, these results suggest the VP2 gene of IPNV can act as candidate gene for vaccine and attenuated multivalent live vaccines and molecular marker vaccines have potential application for viral vaccine.

Recombinant infectious hematopoietic necrosis virus expressing infectious pancreatic necrosis virus VP2 protein induces immunity against both pathogens.

Infectious hematopoietic necrosis virus (IHNV) and infectious pancreatic necrosis virus (IPNV) are typical pathogens of rainbow trout. Their co-infection is also common, which causes great economic loss in juvenile salmon species. Although vaccines against IHNV and IPNV have been commercialized in many countries, the prevalence of IHNV and IPNV is still widespread in modern aquaculture. In the present study, two IHNV recombinant viruses displaying IPNV VP2 protein (rIHNV-IPNV VP2 and rIHNV-IPNV VP2COE) were generated using the RNA polymerase Ⅱ system to explore the immunogenicity of IHNV and IPNV. The recombinant IHNV viruses were stable, which was confirmed by sequencing, indirect immunofluorescence assay, western blotting, transmission electron microscopy and viral growth curve assay. IHNV and IPNV challenge showed that the recombinant viruses had high protection rates against IHNV and IPNV with approximately 65% relative percent survival rates. Rainbow trout (mean weight 20 g) vaccinated with these two recombinant viruses showed a high level of antibodies against IHNV and IPNV infection. Taken together, our findings demonstrate that rIHNV-IPNV VP2 and rIHNV-IPNV VP2COE might be promising vaccine candidates against IHNV and IPNV.

EvaGreen-based real-time PCR assay for sensitive detection of salmonid alphavirus.

Salmonid alphaviruses (SAVs), which include the etiological agents of salmon pancreas disease (PD) and sleeping disease (SD), are significant viral pathogens of European salmonid aquaculture, resulting in substantial economic losses to the salmonid-farming industry. Even though many countries including China have not reported the presence of SAV infections, these countries may be seriously threatened by these diseases as the salmon fish import trade increases. Thus, it is indeed necessary to develop efficient detection methods for the diagnosis and prevention of SAV infection. Real-time PCR assays have been increasingly used in viral detection, and in many cases scientists prefer dye-based real-time PCR assays for their high sensitivity and low cost. In this study, we developed a novel, sensitive, low-cost detection method, EvaGreen-based real-time PCR assay for the detection of SAV. This assay exhibited high specificity for SAV1, SAV2, and SAV5 and was able to detect SAV at concentrations as low as 1.5 × 101 copies, making them more sensitive than the approved conventional RT-PCR method (detection limit, 1.5 × 106 copies). Assessment of infected fish samples showed that the sensitivity of EvaGreen-based assay was higher than previously developed SYBR Green assay (227 assay). Thus, we report that the EvaGreen real-time PCR assays is an economical alternative diagnostic method for the rapid detection of SAV1, SAV2, and SAV5 infection, providing improved technical support for the clinical diagnosis and epidemiological investigation of SAV.