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Bisphenol compounds (BPs) have various industrial uses and can enter the environment through various sources. To evaluate the ecotoxicity of BPs and identify potential gene candidates involved in the plant toxicity, Arabidopsis thaliana was exposed to bisphenol A (BPA), BPB, BPE, BPF, and BPS at 1, 3, 10 mg/L for a duration of 14 days, and their growth status were monitored. At day 14, roots and leaves were collected for internal BPs exposure concentration detection, RNA-seq (only roots), and morphological observations. As shown in the results, exposure to BPs significantly disturbed root elongation, exhibiting a trend of stimulation at low concentration and inhibition at high concentration. Additionally, BPs exhibited pronounced generation of reactive oxygen species, while none of the pollutants caused significant changes in root morphology. Internal exposure concentration analysis indicated that BPs tended to accumulate in the roots, with BPS exhibiting the highest level of accumulation. The results of RNA-seq indicated that the shared 211 differently expressed genes (DEGs) of these 5 exposure groups were enriched in defense response, generation of precursor metabolites, response to organic substance, response to oxygen-containing, response to hormone, oxidation-reduction process and so on. Regarding unique DEGs in each group, BPS was mainly associated with the redox pathway, BPB primarily influenced seed germination, and BPA, BPE and BPF were primarily involved in metabolic signaling pathways. Our results provide new insights for BPs induced adverse effects on Arabidopsis thaliana and suggest that the ecological risks associated with BPA alternatives cannot be ignored.
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Arabidopsis , Compuestos de Bencidrilo , Oxidación-Reducción , Fenoles , Raíces de Plantas , Arabidopsis/efectos de los fármacos , Arabidopsis/genética , Fenoles/toxicidad , Compuestos de Bencidrilo/toxicidad , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/metabolismo , RNA-Seq , Análisis de Secuencia de ARN , Contaminantes del Suelo/toxicidadRESUMEN
OBJECTIVES: This study aimed to evaluate the surgical outcomes of composite-valve root replacement with bioprosthesis (b-CVRR) after acute type A aortic dissection (AAAD) repair. METHODS: We included 41 patients who underwent b-CVRR after surgery for AAAD from 2007 to 2022. We excluded seven patients with VSRR, three with mechanical valve use, one with mycotic aneurysm, and one with cardiopulmonary resuscitation. RESULTS: The overlapping surgical indications for b-CVRR were pseudoaneurysm in 21 patients (51.2%), severe AI in 19 (46.3%), re-dissection in 15 (36.6%), root dilatation (> 50 mm) in 12 (41.5%), and rupture in 3 (7.3%). The coronary artery reconstruction methods were bilateral Carrel patch in 13 patients (32%), Carrel patch with Piehler in 16 patients (38%), bilateral Piehler in six patients (15%), and Piehler with coronary artery bypass (CABG) in six patients (15%). Four patients who underwent the Carrel patch technique required additional intraoperative CABG. Three hospital mortality occurred (7.3%; myonephropathic metabolic syndrome, heart failure, bleeding from the thyroid carotid artery without injury). No thrombosis of the reconstructed site was observed with the Piehler procedure. CONCLUSION: Surgical outcomes for patients treated with b-CVRR after AAAD repair were acceptable. Intraoperative coronary artery events occurred due to stenosis caused by traction on the reconstructed coronary artery due to adhesions.
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Amino acids serve as the primary means of transport and organic nitrogen carrier in plants, playing an essential role in plant growth and development. Amino acid transporters (AATs) facilitate the movement of amino acids within plants and have been identified and characterised in a number of species. It has been demonstrated that these amino acid transporters exert an influence on the quality attributes of plants, in addition to their primary function of transporting amino acid transport. This paper presents a summary of the role of AATs in plant quality improvement. This encompasses the enhancement of nitrogen utilization efficiency, root development, tiller number and fruit yield. Concurrently, AATs can bolster the resilience of plants to pests, diseases and abiotic stresses, thereby further enhancing the yield and quality of fruit. AATs exhibit a wide range of substrate specificity, which greatly optimizes the use of pesticides and significantly reduces pesticide residues, and reduces the risk of environmental pollution while increasing the safety of fruit. The discovery of AATs function provides new ideas and ways to cultivate high-quality crop and promote changes in agricultural development, and has great potential in the application of plant quality improvement.
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Microplastics are heterogeneously distributed in soils. However, it is unknown whether soil microplastic heterogeneity affects plant growth and root foraging responses and whether such effects vary with plant species and microplastic types. We grew each of seven herbaceous species (Platycodon grandiflorus, Trifolium repens, Portulaca oleracea, Medicago sativa, Taraxacum mongolicum, Perilla frutescenst, and Paspalum notatum) in heterogeneous soil (patches without microplastics and patches with 0.2â¯% microplastics) and homogeneous soil (patches with 0.1â¯% microplastics). Three microplastic types were tested: polypropylene (PP), polyacrylonitrile (PAN), and polyester (PET). P. frutescens showed no response to soil microplastic heterogeneity. For P. grandiflora, microplastic heterogeneity tended to decrease its biomass (total, shoot and root) when the microplastic was PAN and also shoot biomass when it was PET, but had no effect when it was PP. For T. repens, microplastic heterogeneity promoted biomass when PAN was used, decreased total and root biomass when PET was used, but showed no effect when PP was used. Microplastic heterogeneity increased biomass of P. oleracea and decreased that of M. sativa when PET was used, but had no effect when PP or PAN was used. For T. mongolicum, microplastic heterogeneity reduced biomass when the microplastic was PAN, tended to increase total and root biomass when it was PP, but showed no effect when it was PET. For P. notatum, microplastic heterogeneity increased biomass when the microplastic was PP, decreased it when PET was used, but had no effect when PAN was used. However, biomass of none of the seven species showed root foraging responses at the patch level. Therefore, soil microplastic heterogeneity can influence plant growth, but such effects depend on species and microplastic types and are not associated with root foraging. Our findings highlight the roles of soil microplastic heterogeneity, which may influence species interactions and community structure and productivity.
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Managing teeth with open apices can be a challenging scenario for clinicians. This case report describes the 24-year follow-up of a maxillary central incisor that failed to develop after a traumatic injury resulting in a wide-open apex. A 10-year-old girl presented complaining of discomfort in her upper teeth. Tooth #9 had received a traumatic blow several years before and was discoloured with a resin composite restoration on the mesio-incisal edge. The tooth was painful to percussion and palpation. An inadequate root canal filling and incomplete root formation were observed on the initial periapical radiograph. Root canal retreatment was initiated, and the canal filled entirely with mineral trioxide aggregate (MTA) because of the extremely wide canal and open apex. The patient was asymptomatic at the 24-year follow-up with the cone beam computed tomography and periapical radiographs demonstrating the stability of the MTA.
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BACKGROUND: Brassica napus L. (B. napus) is susceptible to waterlogging stress during different cultivation periods. Therefore, it is crucial to enhance the resistance to waterlogging stress to achieve a high and stable yield of B. napus. RESULTS: Here we observed significant differences in the responses of two B. napus varieties in root under waterlogging stress. The sensitive variety (23651) exhibited a more pronounced and rapid reduction in cell wall thickness and root integrity compared with the tolerant variety (Santana) under waterlogging stress. By module clustering analysis based on transcriptome data, we identified that cell wall polysaccharide metabolism responded to waterlogging stress in root. It was found that pectin content was significantly reduced in the sensitive variety compared with the tolerant variety. Furthermore, transcriptome analysis revealed that the expression of two homologous genes encoding polygalacturonase-inhibiting protein 2 (PGIP2), involved in polysaccharide metabolic pathways, was highly upregulated in root of the tolerant variety under waterlogging stress. BnaPGIP2s probably confer waterlogging resistance by inhibiting the activity of polygalacturonases (PGs), which in turn reduces the degradation of the pectin backbone polygalacturonic acid. CONCLUSIONS: Our findings demonstrate that cell wall polysaccharides in root plays a vital role in response to the waterlogging stress and provide a theoretical foundation for breeding waterlogging resistance in B. napus varieties.
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Brassica napus , Pared Celular , Raíces de Plantas , Polisacáridos , Estrés Fisiológico , Brassica napus/fisiología , Brassica napus/genética , Pared Celular/metabolismo , Polisacáridos/metabolismo , Raíces de Plantas/fisiología , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Pectinas/metabolismo , Agua/metabolismoRESUMEN
Leguminous tree root nodule nitrogen-fixing bacteria are critical for recuperation of soil C and N cycle processes after disturbance in tropical forests, while other nodule-associated bacteria (NAB) may enhance nodule development and activity, and plant growth. However, little is known of these root nodule microbiomes. Through DNA analysis, we evaluated the bacterial taxa associated with the root nodules of the 1-year-old, 2-year-old, 13-year-old, and old growth Inga punctata trees in a cloud forest. Bradyrhizobium diazoefficiens was the dominant taxon found in all nodules at 63.16% to 85.71% mean percent sequences (MPS) of the total nodule bacterial DNA and was found in the youngest nodules examined (1 year old), suggesting that it is the primary nodular bacteria. There were 26 other NAB genera with collective MPS levels between 7.4% to 12.2%, while 15 of these genera were found in the Bulk Forest soils at collective MPS levels of 4.6%. These bacterial community compositions were different between the NAB and Bulk Forest soils, suggesting the NAB became concentrated within the root nodules, resulting in communities with different compositions from the Bulk Forest soils. Twenty-three of the 26 NAB genera were previously identified with the potential to perform 9 plant growth promoting (PGP) activities, suggesting their importance in root nodule development and plant growth. These NAB communities appeared to successionally develop over time into more complex taxonomic communities, which is consistent with the outcome of advanced microbial communities following succession. The presence of both B. diazoefficiens and the NAB communities in the nodules across all ages of tree roots, and the potential for PGP activities linked with most of the NAB genera, suggest the importance of B. diazoefficiens and the NAB community for nodule development and enhanced development and growth of I. punctata throughout its lifespan, and most critically in the younger plants.
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Avulsion occurs when the tooth is completely knocked out of its alveolar socket. The maxillary central incisors are more vulnerable to avulsion due to their prominent position in the dental arch. This case report describes a successful permanent maxillary incisor replantation in an 11-year-old child. The replanted tooth was stabilized in the socket using orthodontic wire, followed by root canal treatment and composite restoration within a two-week interval. Clinical and radiographic follow-up was done at one and six months. Successful management of an avulsed tooth requires educating the patient about different storage mediums and emergency management after an avulsion. This case report concluded that the avulsed tooth result is highly dependent on the patient's understanding of avulsion and how to approach it.
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Introduction: Negative oxygen ions are produced by plants through photosynthesis, utilizing "tip discharge" or the photoelectric effect, which has various functions such as sterilization, dust removal, and delaying aging. With global warming, high temperatures may affect the ability of Phalaenopsis aphrodite Rchb. f. to produce negative oxygen ions. P. aphrodite is commonly used in modern landscape planning and forest greening. Methods: In this study, P. aphrodite was selected as the research object. By artificially simulating the climate, the control group (CK) and the high temperature stress group (HS) were set up in the experiment. Results: The study found that compared with the control group, the ability of P. aphrodite to produce negative oxygen ions significantly decreased when exposed to high temperature stress. Meanwhile, under high temperature stress treatment, peroxidase content increased by 102%, and proline content significantly increased by 35%. Discussion: Redundancy analysis results indicated a significant correlation between the root endophytic microbial community of P. aphrodite and negative oxygen ions, as well as physiological indicators. Under high temperature stress, P. aphrodite may affect the regulation of physiological indicators by modifying the composition of root endophytic microbial communities, thereby influencing the ability to release negative oxygen ions.
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Investigating the quantity and spatiotemporal dynamics of metabolite release from plant roots is essential if we are to understand the ecological significance of root exudates in the rhizosphere; however, this is difficult to quantify. In the present study, we quantified in situ root exudation rates during three incubation periods (0-24, 24-48, and 48-72 h) and fine roots within four diameter ranges (<0.8, 0.8-1.0, 1.0-1.2, and 1.2-2.0 mm), and also measured nine morphological traits in the fine roots of Pinus massoniana. Higher root carbon (C) exudation rates were detected during the 0-24 h period. During the 0-24 h and 24-48 h periods, nitrogen (N) uptake rates were higher than N exudation rates, while during the 48-72 h period, N exudation rates exceeded uptake rates. As C exudation increased during 0-48h incubation period, the uptake of N tended to level out. We concluded that the 24-48 h incubation period was the most suitable for capturing root exudates from P. massoniana. The exudation of C from the roots was positively associated with root mass, length, surface area, volume, the number of root tips, and the root tissue density, when incubated for 0-24 h and 24-48 h. Furthermore, length-specific C exudation rates, along with N exudation and uptake rates, all increased as the diameter of the fine roots increased. The release of root exudates could be efficiently predicted by the fine root morphological traits, although the accuracy of prediction depended on the incubation period. Higher values for fine root morphological traits were generally indicative of higher nutrient requirements and tissue investment, as well as higher C exudation rates.
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Atrazine, a commonly employed herbicide for corn production, can leave residues in soil, resulting in photosynthetic toxicity and impeding growth in subsequent alfalfa (Medicago sativa L.) crops within alfalfa-corn rotation systems. The molecular regulatory mechanisms by which atrazine affects alfalfa growth and development, particularly its impact on the microbial communities of the alfalfa rhizosphere, are not well understood. This study carried out field experiments to explore the influence of atrazine stress on the biomass, chlorophyll content, antioxidant system, and rhizosphere microbial communities of the atrazine-sensitive alfalfa variety WL-363 and the atrazine-resistant variety JN5010. The results revealed that atrazine significantly reduced WL-363 growth, decreasing plant height by 8.58 cm and root length by 5.42 cm (p < 0.05). Conversely, JN5010 showed minimal reductions, with decreases of 1.96 cm in height and 1.26 cm in root length. Chlorophyll content in WL-363 decreased by 35% under atrazine stress, while in JN5010, it was reduced by only 10%. Reactive oxygen species (ROS) accumulation increased by 60% in WL-363, compared to a 20% increase in JN5010 (p < 0.05 for both). Antioxidant enzyme activities, such as superoxide dismutase (SOD) and catalase (CAT), were significantly elevated in JN5010 (p < 0.05), suggesting a more robust defense mechanism. Although the predominant bacterial and fungal abundances in rhizosphere soils remained generally unchanged under atrazine stress, specific microbial groups exhibited variable responses. Notably, Promicromonospora abundance declined in WL-363 but increased in JN5010. FAPROTAX functional predictions indicated shifts in the abundance of microorganisms associated with pesticide degradation, resistance, and microbial structure reconstruction under atrazine stress, displaying different patterns between the two varieties. This study provides insights into how atrazine residues affect alfalfa rhizosphere microorganisms and identifies differential microbial responses to atrazine stress, offering valuable reference data for screening and identifying atrazine-degrading bacteria.
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Background: Knowledge of the anatomy and morphology of root canal orifices and variations are vital elements affecting treatment outcomes. Aim: The objective of this study was to evaluate variations in the number of root canal orifices and their patterns in primary teeth, as identified by both the naked eye and under magnifying loupes. Materials and methods: Total of 173 primary teeth was scheduled for pulpectomy over a period of 18 months. Two examiners assessed the number and pattern of the root canal orifices. After access cavity preparation, the operator recorded the number of root canal orifices with naked eye, and examiner recorded the same using magnifying loupes (3.5×). After cleaning and shaping, the same protocol was used. Collected data were statistically analyzed using SPSS version 23.0 and compared using a paired t-test. Results: The overall variation in the in the identification of root canal orifices between the naked eye and magnifying loupes (3.005 ± 0.971) was statistically significant after access cavity preparation (P ≤ 0.05). Conclusion: Magnifying loupes significantly enhances the determination of the number and pattern of root canal orifices in primary teeth. Therefore, the application of magnifying loupes is essential for accurately assessing variations in root canal orifices in primary dentition.
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Extraoral sinus tracts of endodontic origin might be confused for a variety of dermatological conditions. Differential diagnosis of this clinical condition plays an essential role in providing appropriate clinical care because misdiagnosis is the most prevalent cause of prolonged therapy and healing failure. As a result, every cutaneous sinus structure affecting the face or neck should be investigated for dental issues. Its diagnosis can sometimes be difficult until the treating clinician examines the potential of a dental cause. Once an appropriate diagnosis has been established, definitive treatment, consisting of root canal therapy or tooth extraction, to remove the primary source of infection is a straightforward and successful operation.
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Root cap cuticles (RCCs), comprising mainly very-long-chain fatty acids (VLCFAs), promote salt tolerance by preventing ion influx. Glycosylphosphatidylinositol-anchored lipid transfer protein (LTPG)1 and LTPG2 participate in VLCFA deposition in the extracellular region, aiding RCC formation in the lateral roots. In this study, we investigated whether LTPG1 and LTPG2 have similar functions in the primary roots of young Arabidopsis thaliana. Phenotypic analyses, fluorescence microscopy, and RT-qPCR confirmed that NaCl exposure induced LTPG1 and LTPG2 expression and promoted RCC formation in young primary roots. The loss of RCC in the ltpg1 and ltpg2 mutants resulted in increased NaCl sensitivity of root elongation. NaCl also upregulated the expression of several NaCl-responsive genes in ltpg1 and ltpg2. We conclude that RCC formation via LTPG function is pivotal in enhancing salt tolerance in young primary roots.
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Ginseng, from the roots of Panax ginseng C. A. Meyer, is a widely used herbal medicine in Asian countries, known for its excellent therapeutic properties. The growth of P. ginseng is depend on specific and strict environments, with a preference for wetness but intolerance for flooding. Under excessive soil moisture, some irregular rust-like substances are deposited on the root epidermis, causing ginseng rusty symptoms (GRS). This condition leads to a significant reduce in yield and quality, resulting in substantial economic loses. However, there is less knowledge on the cause of GRS and there are no effective treatments available for its treatment once it occurs. Unsuitable environments lead to the generation of large amounts of reactive oxygen species (ROS). We investigated the key indicators associated with the stress response during different physiological stages of GRS development. We observed a significant change in ROS level, MDA contents, antioxidant enzymes activities, and non-enzymatic antioxidants contents prior to the GRS. Through the analysis of soil features with an abundance of moisture, we further determined the source of ROS. The levels of nitrate reductase (NR) and nitric oxide synthase (NOS) activities in the inter-root soil of ginseng with GRS were significantly elevated compared to those of healthy ginseng. These enzymes boost nitric oxide (NO) levels, which in turn showed a favorable correlation with the GRS. The activities of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase first rose and then decreased as GRS developed. Excess soil moisture causes a decrease in oxygen levels. This activated NR and NOS in the soil, resulting in a production of excess NO. The NO then diffused into the ginseng root and triggered a burst of ROS through NADPH located on the cell membrane. Additionally, Fe2+ in soil was oxidized to red Fe3+, and finally led to GRS. This conclusion was also verified by the Sodium Nitroprusside (SNP), a precursor compound producing NO. The presence of NO from NR and NOS in water-saturated soil is responsible for the generation of ROS. Among these, NO is the main component that contribute to the occurrence of GRS.
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Óxido Nítrico , Panax , Raíces de Plantas , Especies Reactivas de Oxígeno , Suelo , Panax/metabolismo , Raíces de Plantas/metabolismo , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/efectos de los fármacos , Óxido Nítrico/metabolismo , Suelo/química , Especies Reactivas de Oxígeno/metabolismo , Estrés Fisiológico , Antioxidantes/metabolismo , Óxido Nítrico Sintasa/metabolismo , Nitrato-Reductasa/metabolismo , Enfermedades de las PlantasRESUMEN
BACKGROUND: Rusted root rot is one of the most common root diseases in Panax ginseng, and Cylindrocarpon destructans is one of the main pathogenic fungus. The objective of this study was to screen and explore the extracts of biocontrol bacteria isolated from ginseng rhizosphere soil against Cylindrocarpon destructans. RESULTS: Bacterial strains Bacillus amyloliquefaciens YY8 and Enterobacteriacea YY115 were isolated and found to exhibit in vitro antifungal activity against C. destructans. A combination of crude protein extract from B. amyloliquefaciens YY8 and ethyl acetate extract from Enterobacteriacea YY115 in a 6:4 ratio exhibited the strongest antifungal activity against C. destructans. Measurements of electrical conductivity, protein content, and nucleic acid content in suspension cultures of C. destructans treated with a mixture extracts indicated that the extracts disrupted the cell membranes of rusted root rot mycelia, resulting in the leakage of electrolytes, proteins, and nucleic acids from the cells, and ultimately inhibiting the growth of C. destructans. The combined extracts suppressed the infection of ginseng roots discs by C. destructans effectively. CONCLUSION: The extracts obtained from the two bacterial strains effectively inhibited C. destructans in P. ginseng. It can provide scientific basis for the development of new biological control pesticides, reduce the use of chemical pesticides, and promote the sustainable development of agriculture.
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Bacillus amyloliquefaciens , Enterobacteriaceae , Panax , Enfermedades de las Plantas , Raíces de Plantas , Panax/microbiología , Panax/química , Bacillus amyloliquefaciens/metabolismo , Bacillus amyloliquefaciens/química , Bacillus amyloliquefaciens/fisiología , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/prevención & control , Raíces de Plantas/microbiología , Enterobacteriaceae/efectos de los fármacos , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Microbiología del Suelo , Rizosfera , Acetatos/farmacología , Ascomicetos/efectos de los fármacos , Ascomicetos/química , Antifúngicos/farmacología , Antifúngicos/metabolismo , Agentes de Control Biológico/farmacologíaRESUMEN
Effector secretion is crucial for root endophytes to establish and protect their ecological niche. We used time-resolved transcriptomics to monitor effector gene expression dynamics in two closely related Sebacinales, Serendipita indica and Serendipita vermifera, during symbiosis with three plant species, competition with the phytopathogenic fungus Bipolaris sorokiniana, and cooperation with root-associated bacteria. We observed increased effector gene expression in response to biotic interactions, particularly with plants, indicating their importance in host colonization. Some effectors responded to both plants and microbes, suggesting dual roles in intermicrobial competition and plant-microbe interactions. A subset of putative antimicrobial effectors, including a GH18-CBM5 chitinase, was induced exclusively by microbes. Functional analyses of this chitinase revealed its antimicrobial and plant-protective properties. We conclude that dynamic effector gene expression underpins the ability of Sebacinales to thrive in diverse ecological niches with a single fungal chitinase contributing substantially to niche defense.
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BACKGROUND: Orthodontically induced inflammatory root resorption (OIIRR) is one of the most important side effects of orthodontic treatment. Low-level laser therapy (LLLT) is a useful way to reduce the orthodontic treatment duration and may have some effect on preventing and repairing OIIRR. However, the specific effects of LLLT on OIIRR remain unknown. OBJECTIVE: Our research aimed to evaluate the Dentin Sialophosphoprotein (DSPP) expression level and root resorption volume during treatment and retention to explore the role of LLLT in preventing and repairing OIIRR. METHODS: Thirty-seven 6-week-old male Sprague-Dawley rats were selected to establish an OIIRR model; the rats were divided into Group B (blank), Group F (force), Group F(LLLT) (force and LLLT), Group F+R (force and retention) and Group F+R(LLLT) (force, retention and LLLT). The root resorption volume of the distal buccal root and mesial root in the maxillary left first molar was calculated by micro-CT, and the DSPP expression level on the compression side of the periodontal ligament was analysed by immunohistochemical staining. RESULTS: The resorption volume in Group F was greater than that in Group F(LLLT). For the mesial root, the volume in Group F was greater than that in Groups F+R and F+R(LLLT). For the distal buccal root, the volume in Groups F and F+R was greater than that in Group F+R(LLLT). The DSPP level in Group F(LLLT) was greater than that in Group F and there was no difference between Groups F+R and F+R(LLLT). CONCLUSIONS: LLLT has a certain preventive effect and a limited reparative effect on OIIRR in rats.
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BACKGROUND: Peripheral nerve injury is a challenging orthopedic issue in clinical management that often leads to limb dysfunction or even disability in severe cases. A thorough exploration of the repair process of peripheral nerve injury and the underlying mechanism contributes to formulate more effective therapeutic strategies. METHODS: In the present study, we established a sciatic nerve transection injury model in Sprague-Dawley (SD) rats. A 12-week compensatory repair of sciatic nerve transection injury using a chitin cannula for small gap anastomosis was then performed via sleeve jointing the proximal common peroneal nerve to the distal tibial nerve and common peroneal nerve, with a 2 mm interval. Compensatory repair via small gap amplification was observed via gross observation of nerve specimen, osmic acid staining, and electrophysiological stimulation of sciatic nerve branches of the tibial and common peroneal nerve. Rat limbs were observed, and the functional recovery of effector muscles of the gastrocnemius and tibialis anterior muscles was assessed through weighing the muscle wet weight, Hematoxylin and Eosin (H&E) staining, and muscle strength detection. H&E staining, Masson staining, and toluidine blue staining were performed to observe the morphological changes of the dorsal root ganglion. Positive expressions of key proteins involved in the Phosphatase and tensin homologue deleted on chromosome ten (PTEN)-protein kinase B (AKT)/mammalian target of rapamycin (mTOR) signaling pathway, including PTEN, AKT, mTOR, Toll-like receptor 4 (TLR4), and Caspase9 in the dorsal root ganglion during compensatory repair of sciatic nerve after injury via small gap amplification, were detected by immunohistochemical staining. RESULTS: It is found that the compensatory repair of sciatic nerve transection injury using a chitin cannula for small gap anastomosis via sleeve jointing effectively restored the continuity, number of myelinated nerve fibers, and nerve conduction velocity. It promoted toe abduction recovery, improved muscle fiber morphology and increased the wet weight and muscle strength of the gastrocnemius muscle and tibialis anterior muscle. Moreover, it increased the number of neurons and nerve fibers, and improved their morphology. Downregulated PTEN, TLR4, and Caspase9 in the dorsal root ganglia and upregulated AKT and mTOR were observed after small gap amplification than those of the transection injury group, which were closer to those of the control group. CONCLUSIONS: Compensatory repair of sciatic nerve transection injury using a chitin cannula for small gap anastomosis via sleeve jointing can restore the morphology and function of the sciatic nerve, effector muscles, and corresponding dorsal root ganglia by activating the PTEN-AKT/mTOR signaling pathway in the dorsal root ganglia. Our findings provide novel therapeutic targets for peripheral nerve injuries.
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Ganglios Espinales , Regeneración Nerviosa , Fosfohidrolasa PTEN , Proteínas Proto-Oncogénicas c-akt , Ratas Sprague-Dawley , Transducción de Señal , Serina-Treonina Quinasas TOR , Animales , Fosfohidrolasa PTEN/metabolismo , Serina-Treonina Quinasas TOR/metabolismo , Transducción de Señal/fisiología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ganglios Espinales/metabolismo , Ratas , Regeneración Nerviosa/fisiología , Modelos Animales de Enfermedad , Masculino , Traumatismos de los Nervios Periféricos/metabolismo , Nervio Ciático/lesiones , Neuropatía Ciática/metabolismoRESUMEN
Previous studies showed that aphid performance was compromised on Brassica nigra infected by root-lesion nematodes (Pratylenchus penetrans, Pp), but less, or positively influenced by root-knot nematode (Meloidogyne spp., Mi) infection. These experiments were on single-nematode infections, while naturally, roots are infected with several nematode species simultaneously. We performed greenhouse assays to assess the effects of single (Mi, Pp) and concurrent (MP)-nematode infections on aphid performance. Using targeted and untargeted profiling of leaf and phloem metabolomes, we examined how single- and concurrent-nematode infections affect shoot metabolomes, and elucidated the possible consequences on aphid performance. We found that the metabolic response towards double-infection is different from single-species infections. Moreover, Mi- and Pp-infections triggered discrete changes in B. nigra leaf and phloem metabolic profiles. Both Pp and MP-infections reduced aphid survival, suggesting that the biological effect could primarily be dominated by Pp-induced changes. This concurred with increased indole glucosinolates and hydroxycinnamic acid levels in the leaves, in particular the putative involvement of salicylic acid-2-O-ß-D-glucoside. This study provides evidence that concurrent infection by different nematode species, as is common in natural environments, is associated with distinct changes in aboveground plant metabolomes, which are linked to differences in the survival of an aboveground herbivore.