[Spatiotemporal Distribution Characteristics of Ground-level-ozone and Its Relationship with Meteorological Conditions in a Representative City in the Bohai Rim from 2017 to 2022].

In recent years, ground-level-ozone（O3） pollution in urban areas in the Bohai Rim has attracted wide attention. Based on the analysis of the spatiotemporal distribution characteristics of O3 concentration in Dongying, a representative city in the Bohai Rim from 2017 to 2022, the effects of meteorological factors and sea-land breeze circulation on O3 concentration were evaluated. The results showed that： ① From 2017 to 2022, the annual assessment value of O3 concentration in Dongying showed a fluctuating upward trend, and the pollution days with O3 as the primary pollutant increased. O3 pollution mainly occurred in spring, summer, and autumn, with the most severe O3 pollution episodes typically occurring in May and June, and the duration of O3 pollution season tended to be longer. The monthly variation in the daily maximum 8-h average ozone （MDA8 O3） presented a bimodal distribution, with significant increases in the 5th and 25th percentiles, and the spatial distribution was "high in the north and south, low in the middle." In addition, the nocturnal O3 concentration in recent years in Dongying also showed a significant increase trend. ② Meteorological factors greatly influenced O3 concentration in Dongying. When the temperature was greater than 30℃, the relative humidity was less than 50%, and the wind direction was south-southwest or east-northeast, a high O3 value was more likely to occur. Meteorological factors contributed 30% of the MDA8 O3 variation in Dongying during the study period. In the case of moderate and severe O3 pollution, the contribution of meteorological factors to the change in MDA8 O3 could be as high as 40%. ③ To some extent, sea-land breeze contributed to the occurrence of MDA8 O3 exceeding the secondary standard limit value of the National Ambient Air Quality Standard. In the afternoon, the hourly concentration of O3 during the sea-land breeze days was approximately 20 µg·m-3 higher than that during the non-sea-land breeze days. On the days of moderate and severe O3 pollution, the O3 concentration during the sea-land breeze days from 10：00 to 16：00 was higher than that during non-sea-land breeze days, and the O3 concentration was also at a high level from 20：00 to 23：00 on sea-land breeze days. In the O3 pollution season, the sea-land breeze could significantly affect the O3 level in coastal cities, which could bring significant challenges for O3 pollution prevention and control in this region. In the future, cities in the Bohai Rim need to further strengthen regional joint prevention and control of O3 pollution and increase emission reduction efforts of nitrogen oxides and volatile organic compounds. This strategy could effectively lower pollutant concentrations within the land breeze air mass, consequently reducing the impact of the sea breeze air mass on air quality in cities in the Bohai Rim.

Nano-laponite encapsulated coaxial fiber scaffold promotes endochondral osteogenesis.

Osteoinductive supplements without side effects stand out from the growth factors and drugs widely used in bone tissue engineering. Lithium magnesium sodium silicate hydrate (laponite) nanoflake is a promising bioactive component for bone regeneration, attributed to its inherent biosafety and effective osteoinductivity. Up to now, the in vivo osteogenic potential and mechanisms of laponite-encapsulated fibrous membranes remain largely unexplored. This study presents a unique method for homogeneously integrating high concentrations of laponite RDS into a polycaprolactone (PCL) matrix by dispersing laponite RDS sol into the polymer solution. Subsequently, a core-shell fibrous membrane (10RP-PG), embedding laponite-loaded PCL in its core, was crafted using coaxial electrospinning. The PCL core's slow degradation and the shell's gradient degradation enabled the sustained release of bioactive ions (Si and Mg) from laponite. In vivo studies on a critical-sized calvarial bone defect model demonstrated that the 10RP-PG membrane markedly enhanced bone formation and remodeling by accelerating the process of endochondral ossification. Further transcriptome analysis suggested that osteogenesis in the 10RP-PG membrane is driven by Mg and Si from endocytosed laponite, activating pathways related to ossification and endochondral ossification, including Hippo, Wnt and Notch. The fabricated nanocomposite fibrous membranes hold great promise in the fields of critical-sized bone defect repair.

Oxygen Switchable Photo-Hydrovoltaic Effect along the Silicon-Water Interface.

Moving boundaries of electrical double layers have shown promising capability in driving directional electron flows in solids, leading to a range of hydrovoltaic effects. The recent discovery of a photohydrovoltaic phenomenon utilizes a moving illumination zone to generate moving boundaries with different properties at the solid-water interface, referred to as the kinetic photovoltaic effect. Here, oxygen was found to act as a chemical switch to turn on and off the kinetic photovoltaic effect. Introducing oxygen would rapidly diminish the kinetic photovoltage in p-Si. On the contrary, degassing oxygen leads to a gradual recovery, whose rate can be facilely speeded up by more than one order through electrostatic gating. Mechanistic investigations of the oxygen switch behavior uncovered a dependence of surface band bending intensity of silicon on oxygen adsorption, which highlights the role of gas molecules, often overlooked, in applications based on semiconductor-liquid interfaces, such as photoelectrochemistry.

In situ comparison of osteogenic effects of polymer-based scaffolds with different degradability by integrated scaffold model.

Polymer-based scaffolds with different degradability have been investigated to screen the matrix whose degradation rate is more closely matched with the bone regeneration rate. However, these comparisons are inclined to be compromised by the animal individual differences. In this study, we constructed an integrated scaffold model comprising four parts with different degradability and bioactivity to achieve an in situ comparison of bone regeneration ability of different scaffolds. Slow-degradable polycaprolactone (PCL), fast-degradable poly (lactic-co-glycolic acid) (PLGA), and silica-coated PCL and PLGA scaffolds were assembled into a round sheet to form a hydroxyapatite (HA)-free integrated scaffold. HA-doped PCL, PLGA, and silica-coated PCL and PLGA scaffolds were assembled to create an HA-incorporated integrated scaffold. The in vivo experimental results demonstrated that the local acid microenvironment caused by the rapid degradation of PLGA interfered with the osteogenic process promoted by PCL-based scaffolds in defect areas implanted with HA-free integrated scaffolds. Since the incorporation of HA alleviated the acidic microenvironment to some extent, each scaffold in HA-incorporated scaffolds exhibited its expected bone regeneration capacity. Consequently, it is feasible to construct an integrated structure for comparing the osteogenic effects of various scaffolds in situ, when there is no mutual interference between the materials. The strategy presented in this study inspired the structure design of biomaterials to enable in situ comparison of bone regeneration capacity of scaffolds.

The lncRNA1-miR6288b-3p-PpTCP4-PpD2 module regulates peach branch number by affecting brassinosteroid biosynthesis.

Branch number is one of the most important agronomic traits of fruit trees such as peach. Little is known about how LncRNA and/or miRNA modules regulate branching through transcription factors. Here, we used molecular and genetic tools to clarify the molecular mechanisms underlying brassinosteroid (BR) altering plant branching. We found that the number of sylleptic branch and BR content in pillar peach ('Zhaoshouhong') was lower than those of standard type ('Okubo'), and exogenous BR application could significantly promote branching. PpTCP4 expressed great differentially comparing 'Zhaoshouhong' with 'Okubo'. PpTCP4 could directly bind to DWARF2 (PpD2) and inhibited its expression. PpD2 was the only one differentially expressed key gene in the path of BR biosynthesis. At the same time, PpTCP4 was identified as a target of miR6288b-3p. LncRNA1 could act as the endogenous target mimic of miR6288b-3p and repress expression of miR6288b-3p. Three deletions and five SNP sites of lncRNA1 promoter were found in 'Zhaoshouhong', which was an important cause of different mRNA level of PpTCP4 and BR content. Moreover, overexpressed PpTCP4 significantly inhibited branching. A novel mechanism in which the lncRNA1-miR6288b-3p-PpTCP4-PpD2 module regulates peach branching number was proposed.

Enzyme-Activated Biomimetic Vesicles Confining Mineralization for Bone Maturation.

Inspired by the crucial role of matrix vesicles (MVs), a series of biomimetic vesicles (BVs) fabricated by calcium glycerophosphate (CaGP) modified polyurethane were designed to mediate the mineralization through in situ enzyme activation for bone therapy. In this study, alkaline phosphatase (ALP) was harbored in the porous BVs by adsorption (Ad-BVs) or entrapment (En-BVs). High encapsulation of ALP on En-BVs was effectively self-activating by calcium ions of CaGP-modified PU that specifically hydrolyzed the organophosphorus (CaGP) to inorganic phosphate, thus promoting the formation of the highly oriented bone-like apatite in vitro. Enzyme-catalyzed kinetics confirms the regulation of apatite crystallization by the synergistic action of self-activated ALP and the confined microcompartments of BVs. This leads to a supersaturated microenvironment, with the En-BVs group exhibiting inorganic phosphate (Pi) levels 4.19 times higher and Ca2+ levels 3.67 times higher than those of simulated body fluid (SBF). Of note, the En-BVs group exhibited excellent osteo-inducing differentiation of BMSCs in vitro and the highest maturity with reduced bone loss in rat femoral defect in vivo. This innovative strategy of biomimetic vesicles is expected to provide valuable insights into the enzyme-activated field of bone therapy.

Composite hydrogels with antioxidant and robust adhesive properties for the prevention of radiation-induced dermatitis.

Radiotherapy is a pivotal means of cancer treatment, but it often leads to radiation dermatitis, a skin injury caused by radiation-induced excess reactive oxygen species (ROS). Scavenging free radicals in the course of radiation therapy will be an effective means to prevent radiation dermatitis. This study demonstrates a novel double network hydrogel doped with MoS2 nanosheets for the prevention of radiation-induced dermatitis. The resultant SPM hydrogel constructed from polyacrylamide (PAM) and sodium alginate (SA) nanofiber presented favorable mechanical and adhesion properties. It could conform well to the human body's irregular contours without secondary dressing fixation, making it suitable for skin protection applications. The in vitro and in vivo experiments showed that the antioxidant properties conferred by MoS2 nanosheets enable SPM to effectively mitigate excessive ROS and reduce oxidative stress, thereby preventing radiation dermatitis caused by oxidative damage. Biosafety assessments indicated good biocompatibility of the composite hydrogel, suggesting SPM's practicality and potential as an external dressing for skin radiation protection.

High-Temperature Superlubricity in MoS2/Graphene van der Waals Heterostructures.

Achieving high-temperature superlubricity is essential for modern extreme tribosystems. Solid lubrication is the sole viable alternative due to the degradation of liquid ones but currently suffers from notable wear, instability, and high friction coefficient. Here, we report robust superlubricity in MoS2/graphene van der Waals heterostructures at high temperatures up to ∼850 K, achieved through localized heating to enable reliable friction testing. The ultralow friction of the MoS2/graphene heterostructure is found to be notably further reduced at elevated temperature and dominantly contributed by the MoS2 edge. The observation can be well described by a multi-contact model, wherein the thermally activated rupture of edge-contacts facilitates the sliding. Our results should be applicable to other van der Waals heterostructures and shed light on their applications for superlubricity at elevated temperature.

A sequential macrophage activation strategy for bone regeneration: A micro/nano strontium-releasing composite scaffold loaded with lipopolysaccharide.

Effective tissue repair relies on the orchestration of different macrophage phenotypes, both the M2 phenotype (promotes tissue repair) and M1 phenotype (pro-inflammatory) deserve attention. In this study, we propose a sequential immune activation strategy to mediate bone regeneration, by loading lipopolysaccharide (LPS) onto the surface of a strontium (Sr) ions -contained composite scaffold, which was fabricated by combining Sr-doped micro/nano-hydroxyapatite (HA) and dual degradable matrices of polycaprolactone (PCL) and poly (lactic-co-glycolic acid) (PLGA). Our strategy involves the sequential release of LPS to promote macrophage homing and induce the expression of the pro-inflammatory M1 phenotype, followed by the release of Sr ions to suppress inflammation. In vitro and in vivo experiments demonstrated that, the appropriate pro-inflammatory effects at the initial stage of implantation, along with the anti-inflammatory effects at the later stage, as well as the structural stability of the scaffolds conferred by the composition, can synergistically promote the regeneration and repair of bone defects.

Paulownia Witches' Broom Disease: A Comprehensive Review.

Phytoplasmas are insect-transmitted bacterial pathogens associated with diseases in a wide range of host plants, resulting in significant economic and ecological losses. Perennial deciduous trees in the genus Paulownia are widely planted for wood harvesting and ornamental purposes. Paulownia witches' broom (PaWB) disease, associated with a 16SrI-D subgroup phytoplasma, is a destructive disease of paulownia in East Asia. The PaWB phytoplasmas are mainly transmitted by insect vectors in the Pentatomidae (stink bugs), Miridae (mirid bugs) and Cicadellidae (leafhoppers) families. Diseased trees show typical symptoms, such as branch and shoot proliferation, which together are referred to as witches' broom. The phytoplasma presence affects the physiological and anatomical structures of paulownia. Gene expression in paulownia responding to phytoplasma presence have been studied at the transcriptional, post-transcriptional, translational and post-translational levels by high throughput sequencing techniques. A PaWB pathogenic mechanism frame diagram on molecular level is summarized. Studies on the interactions among the phytoplasma, the insect vectors and the plant host, including the mechanisms underlying how paulownia effectors modify processes of gene expression, will lead to a deeper understanding of the pathogenic mechanisms and to the development of efficient control measures.

A Novel Strategy for Fabrication of Polyamide 66/Nanohydroxyapatite Composite Bone Repair Scaffolds by Low-Temperature Three-Dimensional Printing.

Due to the decomposition temperature of Polyamide 66 (PA66) in the environment is close to its thermoforming temperature, it is difficult to construct porous scaffolds of PA66/nanohydroxyapatite (PA66/HAp) by fused deposition modeling (FDM) three-dimensional (3D) printing. In this study, we demonstrated for the first time a method for 3D printing PA66/HAp composites at room temperature, prepared PA66/HAp printing ink using a mixed solvent of formic acid/dichloromethane (FA/DCM), and constructed a series of composite scaffolds with varying HAp content. This printing system can print composite materials with a high HAp content of 60 wt %, which is close to the mineral content in natural bone. The physicochemical evaluation presented that the hydroxyapatite was uniformly distributed within the PA66 matrix, and the PA66/HAp composite scaffold with 30 wt % HAp content exhibited optimal mechanical properties and printability. The results of in vitro cell culture experiments indicated that the incorporation of HAp into the PA66 matrix significantly improved the cell adhesion, proliferation, and osteogenic differentiation of bone marrow stromal cells (BMSCs) cultured on the scaffold. In vivo animal experiments suggested that the PA66/HAp composite material with 30 wt % HAp content had the best structural maintenance and osteogenic performance. The three-dimensional PA66/HAp composite scaffold prepared by low temperature printing in the current study holds great potential for the repair of large-area bone defects.

Effectiveness and safety of auricular acupuncture on adjuvant analgesia in patients with total knee arthroplasty: a randomized sham-controlled trial.

Objective: This study aimed to evaluate the effectiveness and safety of auricular acupuncture (AA) on postoperative analgesia, the degree of postoperative nausea, and the effect of inflammation after total knee arthroplasty (TKA). Methods: This was a single-center, placebo-controlled, randomized clinical trial. In total, 96 patients were randomly divided into an AA group with an indwelling intradermal needle (n = 48) and a sham auricular acupuncture (SAA) group with a non-penetrating placebo needle (n = 48). Intra-spinal anesthesia was adopted in both groups during surgery, and an epidural analgesic pump was implanted after surgery for 48 h. The primary outcome was the post-surgery visual analog score (VAS) of resting and movement states (at 6, 12 h and 1, 2, 3, 5, and 7 days). The secondary outcomes included additional doses of analgesic injection during the treatment, C-reactive protein (CRP) levels, erythrocyte sedimentation rate (ESR), and white blood cell (WBC) count on the 1st, 3rd, and 7th day after the operation, nausea on the 1st, 2nd, and 3rd day after the operation, the Hospital for Special Surgery Knee Score (HSS) on the 2nd and 12th week after the operation, and adverse events. Results: The VAS in the AA group at 6 h, 12 h, 2, 3, and 5 days after surgery were lower than those of the SAA group (p < 0.05). Among the secondary outcomes, the total dose of additional analgesic injection after surgery in the AA group was lower than that in the SAA group (p < 0.05). The serum CRP on the 1st day after operation in the AA group was lower than that in the SAA group (p < 0.05). The degree of nausea on 2nd day after surgery in the AA group was lower than that in the SAA group (p < 0.05). There was no significant difference in other outcomes (p > 0.05). Conclusion: In this study, AA was shown to be an effective and safe complementary and alternative therapy for pain relief after TKA, which was able to reduce the total postoperative dose of additional painkillers, decrease serum CRP 1 day after surgery, and improve the degree of postoperative nausea. Clinical trial registration: www.chictr.org.cn, ChiCTR2100054403.

Preparation of Co-Ni-Ce/TiC alloy coatings by double-pulse under a sulfamic acid system and a process mechanism study.

To enhance the protective ability of copper crystallizers and extend their service life, this study explores the use of double pulse co-deposition under a sulfamic acid system to create protective coatings such as Co-Ni. The hardness test and friction wear analysis compare Co-Ni, Co-Ni-Ce, and Co-Ni-Ce/TiC coatings, revealing that the Co-Ni-Ce/TiC coating exhibits the most outstanding protective performance. SEM and XRD techniques are employed to characterize the three protective coatings, demonstrating that the incorporation of rare-earth cerium and nanoparticles improves the coating morphology and modifies their crystalline phase structure. Furthermore, cyclic voltammetry tests on the plating solutions of the three protective coatings indicate that the addition of Ce3+ and nanoparticles influences the deposition potentials. The deposition of Co2+ and Ni2+ follows a two-step, two-electron process, while the deposition of Ce3+ follows a one-step, three-electron process. It is observed that the deposition of all three ions is irreversible. To gain further insights into the nucleation mechanism of Ce3+, a chronoamperometry test is conducted, revealing that the nucleation of Ce3+ is a transient process controlled by diffusion.

A rapid and efficient Agrobacterium-mediated transient transformation system in grape berries.

Transient transformation is extremely useful for rapid in vivo assessment of gene function, especially for fruit-related genes. Grape berry, while an important fruit crop, is recalcitrant to transient transformation, due to the high turgor pressure in its mesocarp cells that limits the ability of Agrobacterium to penetrate into the tissue. It is urgent to establish a simple transient transformation system for rapid analysis of gene function. In this study, different injection methods, grape genotypes, and developmental stages were tested in order to develop a rapid and efficient Agrobacterium-mediated transient transformation methodology for grape berries. Two injection methods, namely punch injection and direct injection, were evaluated using the ß-glucuronidase (GUS) gene and by x-gluc tissue staining and 4-methylumbelliferyl-ß-D-glucuronide fluorescence analysis. The results indicated that there were no significant differences on transformation effects between the two methods, but the latter was more suitable because of its simplicity and convenience. Six grape cultivars ('Hanxiangmi', 'Moldova', 'Zijixin', 'Jumeigui', 'Shine-Muscat', and 'A17') were tested for transient transformation. 'Hanxiangmi', 'Moldova', and 'Zijixin' grape berries were not suitable for agroinfiltration due to frequently fruit cracking, browning, and formation of scar skin. The fruit integrity rates of 'Jumeigui', 'Shine-Muscat', and 'A17' berries were all above 80%, and GUS activity was detected in the berries of the three cultivars 3-14 days after injection with the Agrobacterium culture, while higher GUS activities were observed in the 'Jumeigui' berries. The levels of GUS activity in injected berries at 7-8 weeks after full blooming (WAFB) were more than twice at 6 WAFB. In subsequent assays, the over-expression of MYB transcription factor VvMYB44 via transient transformation accelerated the anthocyanin accumulation and fruit coloring through raising the expression levels of VvLAR1, VvUFGT, VvLDOX, VvANS, and VvDFR, which verified the effectiveness of this transformation system. These experiments finally identified the reliable grape cultivars and suitable operational approach for transient transformation and further indicated that this Agrobacterium-mediated transient transformation system was efficient and suitable for the elucidation of gene function in grape berries.

M2 macrophage-derived exosome-functionalized topological scaffolds regulate the foreign body response and the coupling of angio/osteoclasto/osteogenesis.

Designing scaffolds that can regulate the innate immune response and promote vascularized bone regeneration holds promise for bone tissue engineering. Herein, electrospun scaffolds that combined physical and biological cues were fabricated by anchoring reparative M2 macrophage-derived exosomes onto topological pore structured nanofibrous scaffolds. The topological pore structure of the fiber and the immobilization of exosomes increased the nanoscale roughness and hydrophilicity of the fibrous scaffold. In vitro cell experiments showed that exosomes could be internalized by target cells to promote cell migration, tube formation, osteogenic differentiation, and anti-inflammatory macrophage polarization. The activation of fibrosis, angiogenesis, and macrophage was elucidated during the exosome-functionalized fibrous scaffold-mediated foreign body response (FBR) in subcutaneous implantation in mice. The exosome-functionalized nanofibrous scaffolds also enhanced vascularized bone formation in a critical-sized rat cranial bone defect model. Importantly, histological analysis revealed that the biofunctional scaffolds regulated the coupling effect of angiogenesis, osteoclastogenesis, and osteogenesis by stimulating type H vessel formation. This study elaborated on the complex processes within the cell microenvironment niche during fibrous scaffold-mediated FBR and vascularized bone regeneration to guide the design of implants or devices used in orthopedics and maxillofacial surgery. STATEMENT OF SIGNIFICANCE: How to design scaffold materials that can regulate the local immune niche and truly achieve functional vascularized bone regeneration still remain an open question. Here, combining physical and biological cues, we proposed new insight to cell-free and growth factor-free therapy, anchoring reparative M2 macrophage-derived exosomes onto topological pore structured nanofibrous scaffolds. The exosomes functionalized-scaffold system mitigated foreign body response, including excessive fibrosis, tumor-like vascularization, and macrophage activation. Importantly, the biofunctional scaffolds regulated the coupling effect of angiogenesis, osteoclastogenesis, and osteogenesis by stimulating type H vessel formation.

Jujube Witches' Broom Phytoplasma Effector Zaofeng3, a Homologous Effector of SAP54, Induces Abnormal Floral Organ Development and Shoot Proliferation.

Plant-pathogenic phytoplasmas secrete specific virulence proteins into a host plant to modulate plant function for their own benefit. Identification of phytoplasmal effectors is a key step toward clarifying the pathogenic mechanisms of phytoplasma. In this study, Zaofeng3, also known as secreted jujube witches' broom phytoplasma protein 3 (SJP3), was a homologous effector of SAP54 and induced a variety of abnormal phenotypes, such as phyllody, malformed floral organs, witches' broom, and dwarfism in Arabidopsis thaliana. Zaofeng3 can also induce small leaves, dwarfism, and witches' broom in Ziziphus jujuba. Further experiments showed that the three complete α-helix domains predicted in Zaofeng3 were essential for induction of disease symptoms in jujube. Yeast two-hybrid library screening showed that Zaofeng3 mainly interacts with proteins involved in flower morphogenesis and shoot proliferation. Bimolecular fluorescence complementation assays confirmed that Zaofeng3 interacted with these proteins in the whole cell. Overexpression of zaofeng3 in jujube shoot significantly altered the expression patterns of ZjMADS19, ZjMADS47, ZjMADS48, ZjMADS77, and ZjTCP7, suggesting that overexpressing zaofeng3 might induce floral organ malformation and witches' broom by altering the expression of the transcriptional factors involved in jujube morphogenesis.

Biodegradable Polyurethane Scaffolds in Regeneration Therapy: Characterization and In Vivo Real-Time Degradation Monitoring by Grafted Fluorescent Tracer.

There is an urgent need to assess material degradation in situ and in real time for their promising application in regeneration therapy. However, traditional monitoring methods in vitro cannot always profile the complicated behavior in vivo. This study designed and synthesized a new biodegradable polyurethane (PU-P) scaffold with polycaprolactone glycol, isophorone diisocyanate, and l-lysine ethyl ester dihydrochloride. To monitor the degradation process of PU-P, calcein was introduced into the backbone (PU-5) as a chromophore tracing in different sites of the body and undegradable fluorescent scaffold (CPU-5) as the control group. Both PU-P and PU-5 can be enzymatically degraded, and the degradation products are molecularly small and biosafe. Meanwhile, by virtue of calcein anchoring with urethane, polymer chains of PU-5 have maintained the conformational stability and extended the system conjugation, raising a structure-induced emission effect that successfully achieved a significant enhancement in the fluorescence intensity better than pristine calcein. Evidently, unlike the weak fluorescent response of CPU-5, PU-5 and its degradation can be clearly imaged and monitored in real time after implantation in the subcutaneous tissue of nude mice. Meanwhile, the in situ osteogeneration has also been promoted after the two degradable scaffolds have been implanted in the rabbit femoral condyles and degraded with time. To sum up, the strategy of underpinning tracers into degradable polymer chains provides a possible and effective way for real-time monitoring of the degradation process of implants in vivo.

Analysis of histopathology and changes of major cytokines in the lesions caused by Mycoplasma ovipneumoniae infection.

BACKGROUND: Mycoplasma ovipneumoniae (M. ovipneumoniae) is one of the main pathogens of sheep pneumonia, causing a series of clinical symptoms, such as depression, anorexia, hyperthermia, cough, dyspnea, and tract secretions. In recent years, the prevalence of M. ovipneumoniae pneumonia has become increasingly serious in sheep farms in Ningxia, China, leading to the death of sheep, and causing significant economic losses. In this study, the pathological organs infected by M. ovipneumoniae were collected to observe histopathological change, to determine the tissue localization of M. ovipneumoniae, and to analyze the cytokine changes, which lays a basis for the diagnosis and pathogenesis of M. ovipneumoniae disease. RESULTS: In this study, M. ovipneumoniae was detected in 97 of 105 samples collected from 13 large-scale sheep farms for nucleic acid by PCR. One representative isolate per farm was isolated from 13 farms. The lesions caused by M. ovipneumoniae were mainly in the trachea, bronchus, and lung, including necrosis of tracheal mucosal epithelial cells, disintegration of some epithelial cells, edema of mucosal lamina propria, with inflammatory cell infiltration, cytoplasmic vacuolization of epithelial cells of bronchial mucosa, massive infiltration of inflammatory cells in the alveolar space of lung, necrosis and hyperplasia of alveolar epithelial cells. Immunohistochemical analysis showed that the proportion of M. ovipneumoniae positive area in the lung was the largest, followed by that in the bronchus and trachea. Compared to healthy animals, diseased animals exhibited up-regulated gene expression levels of IL-1ß, IL-6, and NF-κB in the trachea, bronchus, and lungs. In contrast, the expression of IL-10, IL-12, and IFN-γ was primarily limited to the trachea and bronchus. The expression of IL-1ß showed differential patterns across different lung regions, with variations observed among lung lobes. Additionally, other cytokines consistently showed significant up-regulation specifically in the bronchus. CONCLUSIONS: M. ovipneumoniae is primarily found in the lungs of infected individuals. NF-κB, an essential transcription factor, is involved in the regulation of IL-1ß transcription. IL-12 may enhance the cytotoxic function of natural killer cells during M. ovipneumoniae infection. Those findings demonstrate the distinct expression profiles of cytokines in various anatomical sites throughout disease progression, suggesting the potential role of bronchial tissue as a major site of immune response.

Hypothetical Proteins of Mycoplasma synoviae Reannotation and Expression Changes Identified via RNA-Sequencing.

Mycoplasma synoviae infection rates in chickens are increasing worldwide. Genomic studies have considerably improved our understanding of M. synoviae biology and virulence. However, approximately 20% of the predicted proteins have unknown functions. In particular, the M. synoviae ATCC 25204 genome has 663 encoding DNA sequences, among which 155 are considered encoding hypothetical proteins (HPs). Several of these genes may encode unknown virulence factors. This study aims to reannotate all 155 proteins in M. synoviae ATCC 25204 to predict new potential virulence factors using currently available databases and bioinformatics tools. Finally, 125 proteins were reannotated, including enzymes (39%), lipoproteins (10%), DNA-binding proteins (6%), phase-variable hemagglutinin (19%), and other protein types (26%). Among 155 proteins, 28 proteins associated with virulence were detected, five of which were reannotated. Furthermore, HP expression was compared before and after the M. synoviae infection of cells to identify potential virulence-related proteins. The expression of 14 HP genes was upregulated, including that of five virulence-related genes. Our study improved the functional annotation of M. synoviae ATCC 25204 from 76% to 95% and enabled the discovery of potential virulence factors in the genome. Moreover, 14 proteins that may be involved in M. synoviae infection were identified, providing candidate proteins and facilitating the exploration of the infection mechanism of M. synoviae.