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1.
Hortic Res ; 11(5): uhae066, 2024 May.
Article in English | MEDLINE | ID: mdl-38725461

ABSTRACT

CaWRKY40 coordinately activates pepper immunity against Ralstonia solanacearum infection (RSI) and high temperature stress (HTS), forms positive feedback loops with other positive regulators and is promoted by CaWRKY27b/CaWRKY28 through physical interactions; however, whether and how it is regulated by negative regulators to function appropriately remain unclear. Herein, we provide evidence that CaWRKY40 is repressed by a SALT TOLERANCE HOMOLOG2 in pepper (CaSTH2). Our data from gene silencing and transient overexpression in pepper and epoptic overexpression in Nicotiana benthamiana plants showed that CaSTH2 acted as negative regulator in immunity against RSI and thermotolerance. Our data from BiFC, CoIP, pull down, and MST indicate that CaSTH2 interacted with CaWRKY40, by which CaWRKY40 was prevented from activating immunity or thermotolerance-related genes. It was also found that CaSTH2 repressed CaWRKY40 at least partially through blocking interaction of CaWRKY40 with CaWRKY27b/CaWRKY28, but not through directly repressing binding of CaWRKY40 to its target genes. The results of study provide new insight into the mechanisms underlying the coordination of pepper immunity and thermotolerance.

2.
Antioxidants (Basel) ; 13(4)2024 Mar 27.
Article in English | MEDLINE | ID: mdl-38671848

ABSTRACT

Glutathione (GSH), a robust endogenous antioxidant, actively participates in the modulation of the redox status of cysteine residues in proteins. Previous studies have indicated that GSH can prevent ß-cell failure and prediabetes caused by chronic oscillating glucose (OsG) administration. However, the precise mechanism underlying the protective effect is not well understood. Our current research reveals that GSH is capable of reversing the reduction in Nrf2 levels, as well as downstream genes Grx1 and HO-1, in the islet ß-cells of rats induced by chronic OsG. In vitro experiments have further demonstrated that GSH can prevent ß-cell dedifferentiation, apoptosis, and impaired insulin secretion caused by OsG. Additionally, GSH facilitates the translocation of Nrf2 into the nucleus, resulting in an upregulation of Nrf2-targeted genes such as GCLC, Grx1, HO-1, and NQO1. Notably, when the Nrf2 inhibitor ML385 is employed, the effects of GSH on OsG-treated ß-cells are abrogated. Moreover, GSH enhances the S-glutathionylation of Keap1 at Cys273 and Cys288, but not Cys151, in OsG-treated ß-cells, leading to the dissociation of Nrf2 from Keap1 and facilitating Nrf2 nuclear translocation. In conclusion, the protective role of GSH against OsG-induced ß-cell failure can be partially attributed to its capacity to enhance Keap1 S-glutathionylation, thereby activating the Nrf2 signaling pathway. These findings provide novel insights into the prevention and treatment of ß-cell failure in the context of prediabetes/diabetes, highlighting the potential of GSH.

3.
Sci Total Environ ; 925: 171326, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38460703

ABSTRACT

Environmental fluoride exposure has been linked to numerous cases of fluorosis worldwide. Previous studies have indicated that long-term exposure to fluoride can result in intellectual damage among children. However, a comprehensive health risk assessment of fluorosis-induced intellectual damage is still pending. In this research, we utilized the Bayesian Benchmark Dose Analysis System (BBMD) to investigate the dose-response relationship between urinary fluoride (U-F) concentration and Raven scores in adults from Nayong, Guizhou, China. Our research findings indecate a dose-response relationship between the concentration of U-F and intelligence scores in adults. As the benchmark response (BMR) increased, both the benchmark concentration (BMCs) and the lower bound of the credible interval (BMCLs) increased. Specifically, BMCs for the association between U-F and IQ score were determined to be 0.18 mg/L (BMCL1 = 0.08 mg/L), 0.91 mg/L (BMCL5 = 0.40 mg/L), 1.83 mg/L (BMCL10 = 0.83 mg/L) when using BMRs of 1 %, 5 %, and 10 %. These results indicate that U-F can serve as an effective biomarker for monitoring the loss of IQ in population. We propose three interim targets for public policy in preventing interllectual harm from fluoride exposure.


Subject(s)
Fluorides , Fluorosis, Dental , Child , Adult , Humans , Fluorides/analysis , Fluorosis, Dental/epidemiology , Benchmarking , Bayes Theorem , Intelligence , China/epidemiology
4.
Chem Biol Interact ; 386: 110771, 2023 Dec 01.
Article in English | MEDLINE | ID: mdl-37866489

ABSTRACT

Chronic obstructive pulmonary disease (COPD) is a common respiratory disease characterized by symptoms of shortness of breath and chronic inflammation. Curcuma zedoaria (Christm.) Roscoe is a well-documented traditional medical herb that is frequently used in the treatment of COPD. Previously, we identified a diarylheptanoid compound (1-(4-hydroxy-5-methoxyphenyl)-7-(4,5-dihydroxyphenyl)-3,5-dihydroxyheptane; abbreviated as HMDD) from this herb that exhibited potent agonistic activity on ß2-adrenergic receptors (ß2 adrenoreceptor) that are present on airway smooth muscle cells. In this work, we used chemically synthesized HMDD compound, and confirmed its bioactivity on ß2 adrenoreceptors. Then by a proteomics study and anti-inflammatory evaluation detections, we found that HMDD downregulated the nucleotide-binding oligomerization domain (NOD)-like receptor (NLR) signaling pathway and suppressed the NLRP3 receptor expression in RAW264.7 macrophages and in a COPD model in A549 lung carcinoma cells. HMDD also decreased nitric oxide production levels, and impacted other interleukins and the phosphorylation of NF-κB and ERK pathways. We performed molecular docking of HMDD on ß2 adrenoreceptor and NLRP3 protein models. This work reports the anti-inflammatory effects of HMDD and suggests a dual-targeting mechanism of ß2-adrenoreceptor agonism and NLRP3 inhibition. Such a mechanism scientifically supports the clinical uses of Curcuma zedoaria (Christm.) Roscoe in treating COPD, as it can simultaneously relieve persistent breathlessness and inflammation. HMDD can be considered as a potential non-steroidal anti-inflammatory drug in novel therapy design for the treatment of COPD and other inflammatory diseases.


Subject(s)
NLR Family, Pyrin Domain-Containing 3 Protein , Pulmonary Disease, Chronic Obstructive , Humans , Curcuma , Diarylheptanoids/pharmacology , Molecular Docking Simulation , Signal Transduction , Anti-Inflammatory Agents/pharmacology , NF-kappa B/metabolism , Inflammation/drug therapy , Pulmonary Disease, Chronic Obstructive/drug therapy
5.
Opt Lett ; 48(19): 4969-4972, 2023 Oct 01.
Article in English | MEDLINE | ID: mdl-37773362

ABSTRACT

A diode laser (LD) end-pumped acousto-optic Q-switched self-frequency-doubled (SFD) Yb:YCa4O(BO3)3 (Yb:YCOB) pulsed green laser was realized for the first time (to our knowledge), with a maximum average output power of 11.6 W and an optical conversion efficiency of 30.0% from the LD to SFD lasers. The wavelength of the SFD lasers was controlled to be 507 nm for improving quantum efficiency up to 96% and reducing thermal effects. The repetition rates ranged from 20 to 500 kHz, and the maximum pulse energy was 312.0 µJ with a peak power of 4.78 kW at a repetition rate of 20 kHz. This work represents the highest output power in the SFD pulsed lasers and provides an efficient and compact way to generate high-power pulsed green lasers that should have important applications in many aspects, such as ultraviolet (UV) laser generation, laser display, and medical, military, and scientific research.

6.
Kaohsiung J Med Sci ; 39(8): 769-778, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37166084

ABSTRACT

Atopic dermatitis (AD) is a chronic and recurrent inflammatory skin disease. Keratinocyte dysfunction plays a central role in AD development. MicroRNA is a novel player in many inflammatory and immune skin diseases. In this study, we investigated the potential function and regulatory mechanism of miR-193b in AD. Inflamed human keratinocytes (HaCaT) were established by tumor necrosis factor (TNF)-α/interferon (IFN)-γ stimulation. Cell viability was measured using MTT assay, while the cell cycle was analyzed using flow cytometry. The cytokine levels were examined by enzyme-linked immunosorbent assay. The interaction between Sp1, miR-193b, and HMGB1 was analyzed using dual luciferase reporter and/or chromatin immunoprecipitation (ChIP) assays. Our results revealed that miR-193b upregulation enhanced the proliferation of TNF-α/IFN-γ-treated keratinocytes and repressed inflammatory injury. miR-193b negatively regulated high mobility group box 1 (HMGB1) expression by directly targeting HMGB1. Furthermore, HMGB1 knockdown promoted keratinocyte proliferation and inhibited inflammatory injury by repressing nuclear factor kappa-B (NF-κB) activation. During AD progression, HMGB1 overexpression abrogated increase of keratinocyte proliferation and repression of inflammatory injury caused by miR-193b overexpression. Moreover, transcription factor Sp1 was identified as the biological partner of the miR-193b promoter in promoting miR-193b expression. Therefore, Sp1 upregulation promotes keratinocyte proliferation and represses inflammatory injury during AD development via promoting miR-193b expression and repressing HMGB1/NF-κB activation.


Subject(s)
Dermatitis, Atopic , HMGB1 Protein , MicroRNAs , Sp1 Transcription Factor , Humans , Dermatitis, Atopic/genetics , HMGB1 Protein/genetics , MicroRNAs/metabolism , NF-kappa B/metabolism , Skin/pathology , Sp1 Transcription Factor/genetics , Tumor Necrosis Factor-alpha/pharmacology
7.
Light Sci Appl ; 12(1): 28, 2023 Jan 24.
Article in English | MEDLINE | ID: mdl-36693852

ABSTRACT

SiC semiconductor is the focus of recent international research. It is also an important raw material for China to achieve carbon emission peak and carbon neutrality. After nearly 20 years of research and development, we focus on the three types SiC crystals, n-type, p-type and semi-insulating, indicating the development of Shandong University for crystal growth. And defects control, electrical property, atomic polishing, and corresponding device authentication all obtain great progress. Total dislocation density of 6-inch n-type substrates decreases to 2307 cm-2, where BPD (Basal Plane Dislocation) lowers to 333 cm-2 and TSD (Threading Screw Dislocation) 19 cm-2. The full width at half maximum (FWHM) (0004) rocking curves is only 14.4 arcsec. The resistivity reaches more than 1E + 12 Ω·cm for semi-insulating SiC and lower than 20 mΩ·cm for n-type SiC. The impurity concentrations in 6-inch high-purity semi-insulating (HPSI) SiC crystals reach extreme low levels. The devices made of various substrate materials have good performance.

8.
J Mol Cell Cardiol ; 176: 21-32, 2023 03.
Article in English | MEDLINE | ID: mdl-36657637

ABSTRACT

The Hippo signaling pathway plays a critical role in cardiovascular development and stem cell differentiation. Using microarray profiling, we found that the Hippo pathway components vestigial-like family member 4 (VGLL4) and TEA domain transcription factor 1 (TEAD1) were upregulated during vascular smooth muscle cell (VSMC) differentiation from H1 ESCs (H1 embryonic stem cells). To further explore the role and molecular mechanisms of VGLL4 in regulating VSMC differentiation, we generated a VGLL4-knockdown H1 ESC line (heterozygous knockout) using the CRISPR/Cas9 system and found that VGLL4 knockdown inhibited VSMC specification. In contrast, overexpression of VGLL4 using the PiggyBac transposon system facilitated VSMC differentiation. We confirmed that this effect was mediated via TEAD1 and VGLL4 interaction. In addition, bioinformatics analysis revealed that Ten-eleven-translocation 2 (TET2), a DNA dioxygenase, is a target of TEAD1, and a luciferase assay further verified that TET2 is the target of the VGLL4-TEAD1 complex. Indeed, TET2 overexpression promoted VSMC marker gene expression and countered the VGLL4 knockdown-mediated inhibitory effects on VSMC differentiation. In summary, we revealed a novel role of VGLL4 in promoting VSMC differentiation from hESCs and identified TET2 as a new target of the VGLL4-TEAD1 complex, which may demethylate VSMC marker genes and facilitate VSMC differentiation. This study provides new insights into the VGLL4-TEAD1-TET2 axis in VSMC differentiation and vascular development.


Subject(s)
Dioxygenases , Pluripotent Stem Cells , Humans , Transcription Factors/genetics , Transcription Factors/metabolism , DNA-Binding Proteins/genetics , DNA-Binding Proteins/metabolism , TEA Domain Transcription Factors , Muscle, Smooth, Vascular/metabolism , Cell Differentiation/physiology , Pluripotent Stem Cells/metabolism , Myocytes, Smooth Muscle/metabolism , Cell Proliferation
9.
IEEE Trans Cybern ; 53(2): 753-764, 2023 Feb.
Article in English | MEDLINE | ID: mdl-35316203

ABSTRACT

An echo state network (ESN) draws widespread attention and is applied in many scenarios. As the most typical approach for solving the ESN, the matrix inverse operation of high computational complexity is involved. However, in the modern big data era, addressing the heavy computational burden problem is necessary. In order to reduce the computational load, an inverse-free ESN (IFESN) is proposed for the first time in this article. Besides, an incremental IFESN is constructed to attain the network topology with theoretical proof on the training error's monotone decline property. Simulations and experiments are conducted on several numerical and real-world time-series benchmarks, and corresponding results indicate that the proposed model is superior to some existing models and possesses excellent practical application potential. The source code is publicly available at https://github.com/LongJin-lab/the-supplementary-file-for-CYB-E-2021-04-0944.

10.
J Environ Sci (China) ; 126: 517-530, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36503778

ABSTRACT

Graphite carbon nitride has many excellent properties as a two-dimensional semiconductor material so that it has a wide application prospect in the field of photocatalysis. However, the traditional problems such as high recombination rate of photogenerated carriers limit its application. In this work, we introduce nitrogen deficiency into g-C3N4 to solve this problem a simple and safe in-situ reduction method. g-C3N4/CaCO3 was obtained by a simple and safe one-step calcination method with industrial-grade micron particles CaCO3. Cyano group modification was in-situ reduced during the thermal polymerization process, which would change the internal electronic structure of g-C3N4. The successful combination of g-C3N4 and CaCO3 and the introduction of cyanide have been proved by Fourier transform infrared spectroscopy and X-ray photoelectron spectrometer. The formation of the cyano group, an electron-absorbing group, promotes the effective separation of photogenic electron hole pairs and inhibits the recombination of photogenic carriers. These advantages result in the generation of more •O2- and 1O2 in the catalytic system, which increases the photocatalytic efficiency of nicotine degradation by ten times. Furthermore, the degradation process of nicotine has been studied in this work to provide a basis for the degradation of nicotine organic pollutants in the air.


Subject(s)
Environmental Pollutants , Nicotine , Catalysis , Cyanides , Electrons
11.
Opt Lett ; 47(24): 6393-6396, 2022 Dec 15.
Article in English | MEDLINE | ID: mdl-36538446

ABSTRACT

We report a high-power self-frequency-doubled (SFD) Yb:YCa4O(BO3)3 laser by employing a simple and high-integration monolithic configuration with an oscillator length of 6 mm. By reducing the reabsorption and increasing the quantum efficiency, the continuous-wave output power of 21.6 W was obtained with an optical conversion efficiency of 19.0% at the wavelength of about 510 nm. To our knowledge, the results represent the highest output power of a SFD laser. We believe that the high-power SFD laser with a highly compact structure will have broad and promising application prospects in laser display, medical treatment, spectral analysis, scientific research, and other fields.

12.
RSC Adv ; 12(45): 28997-29002, 2022 Oct 11.
Article in English | MEDLINE | ID: mdl-36320762

ABSTRACT

Photothermal materials based on organic small molecules have the characteristics of structural diversity and easy modification for solar-driven water evaporation and power generation technology. However, there still exist limitations, such as the utilization of solar energy and photostability. Therefore, it is the focus of current research to design organic photothermal materials with excellent photothermal stability, strong solar absorption capacity, and high photothermal conversion efficiency. Herein, photothermal conversion materials based on tetrapyridylporphyrin (TPyP) is studied, which possesses polypyrrole macrocyclic framework (18π electrons), which makes it exhibit strong absorption in the 300-800 nm region with high photothermal conversion. The interfacial-heating evaporation system based on polyurethane (PU) foam loaded with TPyP was prepared, whose solar-to-vapor conversion efficiency and vapor evaporation rate of PU + TPyP foam solar energy reached 56% and 0.81 kg m-2 h-1, respectively. In addition, TPyP-loaded solar evaporator equipped with abundant microchannels for water flow are integrated with thermoelectric devices, thus achieving an evaporation rate and voltage as high as 0.69 kg m-2 h-1 and 60 mV under 1 kW m-2 solar irradiation, respectively. The successful application of TPyP in water evaporation and power generation effectively addresses the difficulties faced in the process of using organic small molecule photothermal materials to solve the energy crisis.

13.
Zhongguo Yi Liao Qi Xie Za Zhi ; 46(5): 529-533, 2022 Sep 30.
Article in Chinese | MEDLINE | ID: mdl-36254481

ABSTRACT

The pathological mechanism of wound healing is complicated and affected by multiple factors. Modern wound dressings are widely used in the clinical management of wound healing and have achieved good therapeutic effects. Clinically, wounds are often caused by different etiologies. However, there are few reviews focus on the selection of reasonable dressings for different types of wounds. This study mainly focuses on the characteristics of commonly used wound dressings and summarizes the characteristics of the most commonly used wound dressings in clinical practice and their effects. The advantages and disadvantages of pathology wounds: diabetic foot ulcers, pressure injuries, burns, and leg ulcers are reviewed. This study aims to provide references for the development and clinical selection of wound dressings for scientific researchers and first-line nursing staff who are engaged in wound dressings.


Subject(s)
Bandages, Hydrocolloid , Diabetic Foot , Humans , Diabetic Foot/pathology , Diabetic Foot/therapy , Wound Healing
14.
Article in English | MEDLINE | ID: mdl-35839197

ABSTRACT

Neural networks have evolved into one of the most critical tools in the field of artificial intelligence. As a kind of shallow feedforward neural network, the broad learning system (BLS) uses a training process based on random and pseudoinverse methods, and it does not need to go through a complete training cycle to obtain new parameters when adding nodes. Instead, it performs rapid update iterations on the basis of existing parameters through a series of dynamic update algorithms, which enables BLS to combine high efficiency and accuracy flexibly. The training strategy of BLS is completely different from the existing mainstream neural network training strategy based on the gradient descent algorithm, and the superiority of the former has been proven in many experiments. This article applies an ingenious method of pseudoinversion to the weight updating process in BLS and employs it as an alternative strategy for the dynamic update algorithms in the original BLS. Theoretical analyses and numerical experiments demonstrate the efficiency and effectiveness of BLS aided with this method. The research presented in this article can be regarded as an extended study of the BLS theory, providing an innovative idea and direction for future research on BLS.

15.
J Elder Abuse Negl ; 34(4): 241-258, 2022.
Article in English | MEDLINE | ID: mdl-35765770

ABSTRACT

This study aims to explore the prevalence of self-neglect and associated factors among older adults admitted to the hospital in the COVID-19 pandemic context. The cross-sectional study conducted at a Chinese comprehensive hospital between January and April 2021, 452 older adults were recruited to complete the Abrams Geriatric Self-Neglect Scale, Social Support Rate Scale, FRAIL scale, Barthel index, Patient Health Questionnaire-9, and 10-item Connor-Davidson Resilience Scale. Multivariate logistic regression was used to explore the factors associated with elder self-neglect. The results showed that the prevalence of self-neglect among our sample was 30.3%. Factors that were associated with the risk of elder self-neglect included male, having multiple children (≥4), receiving infrequent visits from children, frailty, and depression. There is a need to screen for self-neglect among older adults admitted to the hospital in the COVID-19 pandemic context. Tailored interventions are warranted to improve the quality of life of older adults.


Subject(s)
COVID-19 , Elder Abuse , Self-Neglect , Aged , China , Cross-Sectional Studies , Geriatric Assessment , Hospitals , Humans , Male , Pandemics , Quality of Life
16.
Cell Death Dis ; 13(5): 440, 2022 05 06.
Article in English | MEDLINE | ID: mdl-35523788

ABSTRACT

The activation of pancreatic stellate cells (PSCs) is the key mechanism of pancreatic fibrosis, which can lead to ß-cell failure. Oxidative stress is an important risk factor for PSC activation. There is no direct evidence proving if administration of glutathione can inhibit fibrosis and ß-cell failure. To explore the role of glutathione in pancreatic fibrosis and ß-cell failure induced by hyperglycaemia, we established a rat model of pancreatic fibrosis and ß-cell failure. The model was founded through long-term oscillating glucose (LOsG) intake and the setup of a sham group and a glutathione intervention group. In vitro, rat PSCs were treated with low glucose, high glucose, or high glucose plus glutathione to explore the mechanism of high glucose-induced PSC activation and the downstream effects of glutathione. Compared with sham rats, LOsG-treated rats had higher reactive oxygen species (ROS) levels in peripheral leukocytes and pancreatic tissue while TGFß signalling was upregulated. In addition, as the number of PSCs and pancreatic fibrosis increased, ß-cell function was significantly impaired. Glutathione evidently inhibited the upregulation of TGFß signalling and several unfavourable outcomes caused by LOsG. In vitro treatment of high glucose for 72 h resulted in higher ROS accumulation and potentiated TGFß pathway activation in PSCs. PSCs showed myofibroblast phenotype transformation with upregulation of α-SMA expression and increased cell proliferation and migration. Treatment with either glutathione or TGFß pathway inhibitors alleviated these changes. Together, our findings suggest that glutathione can inhibit PSC activation-induced pancreatic fibrosis via blocking ROS/TGFß/SMAD signalling in vivo and in vitro.


Subject(s)
Pancreatic Stellate Cells , Transforming Growth Factor beta , Animals , Cells, Cultured , Fibrosis , Glucose/metabolism , Glucose/toxicity , Glutathione/metabolism , Pancreas/pathology , Pancreatic Stellate Cells/metabolism , Rats , Reactive Oxygen Species/metabolism , Transforming Growth Factor beta/metabolism
17.
Chemosphere ; 299: 134375, 2022 Jul.
Article in English | MEDLINE | ID: mdl-35314181

ABSTRACT

As some of the most promising alternatives to traditional non-degradable materials, photodegradable materials have advantages of environmental benignity and rapid degradation under simple conditions. In this work, nontoxic TiO2 and cost-effective g-C3N4 have been compounded in a weight of 9:1 to form a photocatalytic additive with high activity. A 25 wt% loading of this photocatalytic additive has been incorporated into the polyacrylonitrile (PAN) by centrifugal electrospinning to prepare an abiotic degradable PAN material. Our results showed that the PAN chain could be almost fully degraded within 90 h in an aqueous medium under simulated sunlight in the absence of microorganisms. Product analysis implied that degradation of the PAN chain mainly involved the breaking of -CN and C-C bonds by radicals, followed by oxidation of terminal groups to carboxyl and gradual mineralization to CO2 and H2O. This design strategy may provide new insight for the production and degradation mechanism of photodegradable polymer.


Subject(s)
Lighting , Sunlight , Acrylic Resins , Catalysis , Titanium
18.
Nanomaterials (Basel) ; 12(3)2022 Jan 21.
Article in English | MEDLINE | ID: mdl-35159691

ABSTRACT

Epitaxial graphene on SiC without substrate interaction is viewed as one of the most promising two-dimensional (2D) materials in the microelectronics field. In this study, quasi-free-standing bilayer epitaxial graphene (QFSBEG) on SiC was fabricated by H2 intercalation under different time periods, and the temperature-dependent Raman spectra were recorded to evaluate the intrinsic structural difference generated by H2 time duration. The G peak thermal lineshift rates dω/dT showed that the H2 intercalation significantly weakened the pinning effect in epitaxial graphene. Furthermore, the G peak dω/dT value showed a perspicuous pinning effect disparity of QFSBEG samples. Additionally, the anharmonic phonon effect was investigated from the Raman lineshift of peaks. The physical mechanism responsible for dominating the G-mode temperature-dependent behavior among samples with different substrate coupling effects was elucidated. The phonon decay process of different samples was compared as the temperature increased. The evolution from in situ grown graphene to QFSBEG was determined. This study will expand the understanding of QFSBEG and pave a new way for its fabrication.

19.
Vet Sci ; 9(1)2022 Jan 12.
Article in English | MEDLINE | ID: mdl-35051111

ABSTRACT

Infectious coryza is an acute infectious respiratory disease in chickens that is caused by Avibacterium paragallinarum (A. paragallinarum). Infectious coryza has major economic effects due to decreased egg production in growing birds and slowed growth in broilers. In this study, we isolated and identified 40 strains of A. paragallinarum from chickens that showed typical clinical signs of coryza in part of China from 2019 to 2020. Using a hemagglutination-inhibition test, 11 isolates were identified as serovar A, 10 isolates were identified as serovar B, and 19 isolates were identified as serovar C. Antimicrobial sensitivity tests showed that high minimum inhibitory concentration (MIC) values were encountered for compounds sulfamethoxine sodium and oxytetracycline hydrochloride. Especially, of the 40 A. paragallinarum isolates, 30% had an MIC value of compound sulfamethoxine sodium of 64 µg/mL, 10% of 128 µg/mL, and 15% of 256 µg/mL. For oxytetracycline hydrochloride, 85% of isolates showed MIC values of 64 µg/mL or more. Excitingly, the MIC values of ß-lactamase (amoxicillin, ampicillin, and ceftiofur) were low, with 77.5%, 70%, and 92.5% of isolates having an MIC value of ≤1 µg/mL, respectively. Our results may provide a reference for the treatment of infectious coryza.

20.
Poult Sci ; 101(1): 101523, 2022 Jan.
Article in English | MEDLINE | ID: mdl-34784516

ABSTRACT

Infectious coryza (IC) is an acute infectious upper respiratory disease in chickens. Recently, the prevalence of IC has increased in China. In this study, to clarify the pathogenic mechanism and innate immune response of Avibacterium paragallinarum (A. paragallinarum), an infection experiment with A. paragallinarum was conducted. Our results showed that the whole course of IC was approximately 7 d. The clinical signs score was highest at 3 dpi and decreased from 5 dpi. A large amount of mucus and exudates was found in the infraorbital sinuses and nasal cavity. The A. paragallinarum contents in blood remained the highest, reaching 9.16 × 105 CFU/g at 5 dpi, which indicated that A. paragallinarum could rapidly invade the host, replicate in the blood and cause bacteremia. A. paragallinarum targets the upper respiratory tract. The infiltration of inflammatory cells, macrophages, and heterophilic granulocytes was only observed in the nasal cavity and infraorbital sinus. The Tlr4 and Nod1 pathways were activated and induced proinflammatory responses in chickens after infection with A. paragallinarum. The expression of Il1ß and Il6 in the nasal cavity was significantly higher than that in the spleen, and it was consistent with the gross lesions and pathological changes. In particular, the expression of Il6 increased 229.07-fold at 1 dpi in the nasal cavity and increased 3.12-fold in the spleen. The high level of proinflammatory cytokines in the nasal cavity at an early stage of infection may be the main factor related to acute upper respiratory inflammation in chickens. These findings provide a reference for the occurrence and development of diseases mediated by A. paragallinarum.


Subject(s)
Chickens , Haemophilus paragallinarum , Animals , Mucus , Spleen , Virulence
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