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1.
Nat Commun ; 15(1): 5586, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38961090

RESUMO

Lateral momentum conservation is typically kept in a non-absorptive rotationally symmetric system through mirror symmetry via Noether's theorem when illuminated by a homogeneous light wave. Therefore, it is still very challenging to break the mirror symmetry and generate a lateral optical force (LOF) in the rotationally symmetric system. Here, we report a general dynamic action in the SO(2) rotationally symmetric system, originating from the polarization-tuned mirror symmetry breaking (MSB) of the light scattering. We demonstrate theoretically and experimentally that MSB can be generally applied to the SO(2) rotationally symmetric system and tuned sinusoidally by polarization orientation, leading to a highly tunable and highly efficient LOF (9.22 pN/mW/µm-2) perpendicular to the propagation direction. The proposed MSB mechanism and LOF not only complete the sets of MSB of light-matter interaction and non-conservative force only using a plane wave but also provide extra polarization manipulation freedom.

2.
BMC Oral Health ; 24(1): 719, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38909194

RESUMO

BACKGROUND: Neurofibroma is a common benign tumor of neuronal origin that can occur as a solitary tumor or as a component of the generalized syndrome of neurofibromatosis. Neurofibromas are primarily located in the subcutaneous soft tissues and commonly involve extra-oral sites. Solitary intraosseous neurofibromas of the oral cavity are infrequent, with occurrences in the maxilla being exceedingly rare. CASE PRESENTATION: A 22-year-old male patient presented with an asymptomatic mass in the maxilla. Cone-beam computed tomography revealed a round, well-outlined, radiolucent lesion with expansive growth. The neoplasm with the complete capsule was completely removed and confirmed as a neurofibroma based on histopathological and immunohistochemical findings. The reported cases of solitary intraosseous neurofibromas located in the maxilla published in the English literature were compiled to assist in the diagnosis of solitary intraosseous neurofibromas of the maxilla. Nine months after the surgery, there were no signs of tumor recurrence or malignant transformation. CONCLUSIONS: This report emphasizes that rare locations of neurofibromas, such as solitary intraosseous neurofibromas in the maxilla, typically demonstrate nonspecific clinical and radiological features. Clinicians should consider solitary intraosseous neurofibromas as possible differential diagnoses and recognize the histopathological and immunohistochemical features to confirm the correct diagnosis. A longer follow-up period is required because of the potential for local recurrence and malignant transformation of these tumors.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Neoplasias Maxilares , Neurofibroma , Humanos , Masculino , Neurofibroma/patologia , Neurofibroma/diagnóstico por imagem , Neurofibroma/cirurgia , Neoplasias Maxilares/patologia , Neoplasias Maxilares/diagnóstico por imagem , Neoplasias Maxilares/cirurgia , Adulto Jovem , Diagnóstico Diferencial
3.
PLoS One ; 19(4): e0288296, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38557995

RESUMO

Network traffic prediction is an important network monitoring method, which is widely used in network resource optimization and anomaly detection. However, with the increasing scale of networks and the rapid development of 5-th generation mobile networks (5G), traditional traffic forecasting methods are no longer applicable. To solve this problem, this paper applies Long Short-Term Memory (LSTM) network, data augmentation, clustering algorithm, model compression, and other technologies, and proposes a Cluster-based Lightweight PREdiction Model (CLPREM), a method for real-time traffic prediction of 5G mobile networks. We have designed unique data processing and classification methods to make CLPREM more robust than traditional neural network models. To demonstrate the effectiveness of the method, we designed and conducted experiments in a variety of settings. Experimental results confirm that CLPREM can obtain higher accuracy than traditional prediction schemes with less time cost. To address the occasional anomaly prediction issue in CLPREM, we propose a preprocessing method that minimally impacts time overhead. This approach not only enhances the accuracy of CLPREM but also effectively resolves the real-time traffic prediction challenge in 5G mobile networks.


Assuntos
Compressão de Dados , Redes Neurais de Computação , Algoritmos , Previsões
4.
World J Clin Cases ; 12(1): 59-67, 2024 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-38292645

RESUMO

BACKGROUND: Cardiovascular disease, particularly myocardial infarction (MI) profound impact on patients' quality of life and places a substantial burden on the healthcare and economy systems. Developments in medical technology have led to the emergence of coronary intervention as an essential method for treating MI. AIM: To assess the effects of cardiac rehabilitation care on cardiac function recovery and negative emotions in MI after coronary intervention. METHODS: This study included a total of 180 patients with MI during the period from June 2022 to July 2023. Selected patients were divided into two groups: An observation group, which receiving cardiac rehabilitation care; a control group, which receiving conventional care. By comparing multiple observation indicators such as cardiac function indicators, blood pressure, exercise tolerance, occurrence of adverse cardiac events, and negative emotion scores between the two groups of patients. All the data were analyzed and compared between two groups. RESULTS: There were 44 males and 46 females in the observation group with an average age of 36.26 ± 9.88 yr; there were 43 males and 47 females in the control group, with an average age of 40.87 ± 10.5 yr. After receiving the appropriate postoperative nursing measures, the results of the observation group showed significant improvement in several indicators compared with the control group. Indicators of cardiac function, such as left ventricular end-diastolic internal diameter and left ventricular ejection fraction were significantly better in the observation group than in the control group (P < 0.05). Exercise endurance assessment showed that the 6-minute walking test distance was significantly increased in the patients of the observation group (P < 0.01). In addition, the incidence of adverse cardiac events was significantly lower in the observation group, and negative mood scores were significantly reduced (P < 0.05). CONCLUSION: Cardiac rehabilitation care after coronary intervention has a significant positive impact on functional recovery. This emphasizes the importance of cardiac rehabilitation care to improve patient recovery.

5.
Sci Rep ; 13(1): 21621, 2023 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-38062094

RESUMO

The optimal surgical approach and placement of plates for the treatment of distal third diaphyseal fracture of the humerus are the subjects of debate. The aim of this retrospective study was to evaluate the clinical and radiographic outcomes of modified medial minimally invasive plate osteosynthesis (MIPO) techniques using a double technique for the treatment of distal third diaphyseal fracture of the humerus. A total of 30 patients with a distal third diaphyseal fracture of the humerus were selected from our hospital. Patients were seen between January 2017 and October 2022. They were treated with a modified medial approach combined with MIPO using a double plate technique. Patient demographics, operation time, bleeding volume, union time, complications, the mean fracture length (FL) and distal cortical length (DCL), and the number of screws in the distal fragment were analyzed. The function of the shoulder and elbow was evaluated using Neer's assessment of the shoulder and Mayo's assessment of the elbow. The FL was 56.1 ± 7.2 mm and the DCL was 38.3 ± 5.3 mm. The mean operative time was 84.8 ± 13.4 min (range 60-110 min). The mean blood loss during surgical treatment was 46.5 ± 10.2 ml (range 30-60 ml). Bone healing was observed in all patients from 10 to 16 weeks (average 12.1 ± 1.7) postoperatively, and one case with poor surgical wound healing was recorded. All the patients had good function of both the shoulder and elbow. The maximum flexibility of the elbow ranged from 130° to 145° (average 138.1 ± 4.8°), with a maximum flexibility straightness ranging from 0° to 5° (average 2.2 ± 1.3°). The Mayo elbow joint function score was 80-100 (average 91.4 ± 5.0). The Neer shoulder joint function score ranged from 85 to 100 (average 92.5 ± 3.9). The modified medial approach was beneficial it did not cause any iatrogenic radial nerve or ulnar nerve injuries. The anterior and the medial side plates are fixed perpendicular to the distal humerus and provide excellent stability at the same time producing better shoulder and elbow joint function.


Assuntos
Fraturas do Úmero , Humanos , Fraturas do Úmero/diagnóstico por imagem , Fraturas do Úmero/cirurgia , Estudos Retrospectivos , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Úmero , Fixação Interna de Fraturas/métodos , Resultado do Tratamento
6.
Science ; 382(6672): eabq8173, 2023 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-37972184

RESUMO

Neuropeptides are key signaling molecules in the endocrine and nervous systems that regulate many critical physiological processes. Understanding the functions of neuropeptides in vivo requires the ability to monitor their dynamics with high specificity, sensitivity, and spatiotemporal resolution. However, this has been hindered by the lack of direct, sensitive, and noninvasive tools. We developed a series of GRAB (G protein-coupled receptor activation‒based) sensors for detecting somatostatin (SST), corticotropin-releasing factor (CRF), cholecystokinin (CCK), neuropeptide Y (NPY), neurotensin (NTS), and vasoactive intestinal peptide (VIP). These fluorescent sensors, which enable detection of specific neuropeptide binding at nanomolar concentrations, establish a robust tool kit for studying the release, function, and regulation of neuropeptides under both physiological and pathophysiological conditions.


Assuntos
Técnicas Biossensoriais , Ilhotas Pancreáticas , Neurônios , Neuropeptídeos , Receptores Acoplados a Proteínas G , Humanos , Fluorescência , Células HEK293 , Neuropeptídeos/análise , Neuropeptídeos/metabolismo , Receptores Acoplados a Proteínas G/agonistas , Receptores Acoplados a Proteínas G/genética , Neurônios/química , Córtex Cerebral/química , Animais , Ratos , Ilhotas Pancreáticas/química
7.
J Environ Manage ; 348: 119400, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37925984

RESUMO

Real Drive Emission (RDE) test with Portable Emission Measurement System (PEMS) is a widely adopted way to assess vehicle emission compliance. However, the current NOx emissions calculation method stipulated in the China VI emission standard easily ignores the NOx emissions during cold start and low-power operation. To study the effect of cold start and low-power operation on the calculation of NOx emissions in the PEMS test, in this study, a China VI Heavy-Duty Vehicle (HDV) for urban use was used to conduct PEMS tests under various vehicle payload conditions. The data analysis results show that the increase in vehicle payload is beneficial to reducing the specific NOx emissions and passing the NOx emission compliance test because the increased payload improves the NOx conversion efficiency of the SCR system. Cold start duration has no obvious relationship with vehicle payload, accounting for only about 4∼6% in each test, but contributing more than 30% of NOx emissions. Due to the effect of the power threshold and the 90th cumulative percentile, the cold start data has little influence on the result of the NOx emissions assessment and the maximum variation of the NOx emissions result in this study is an 8% rise. For the HDV for urban use, the variation of the power threshold resulting from vehicle payload is small, no more than 2% in this study. The presence of the power threshold makes almost only the low-power operation in the second half of urban driving have an impact on the NOx emissions calculation, which may make more than 50% of NOx emissions in the PEMS test be neglected. The impact of the low-power operation on NOx emissions calculation result will be significantly enhanced if all windows are considered in the Moving Average Window (MAW) method. In the meantime, the degree of variation is closely related to the NOx emissions level during the first half of urban driving. The maximum deterioration of NOx emission assessment result can be more than 90% in this study.


Assuntos
Poluentes Atmosféricos , Poluentes Atmosféricos/análise , Veículos Automotores , Emissões de Veículos/análise , China , Gasolina/análise
8.
Structure ; 31(10): 1275-1281.e4, 2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37527655

RESUMO

Focused ion beam (FIB) is widely used for thinning frozen cells to produce lamellae for cryo-electron microscopy imaging and for protein structures study in vivo. However, FIB damages the lamellae and a quantitative experimental analysis of the damage is lacking. We used a 30-keV gallium FIB to prepare lamellae of a highly concentrated icosahedral virus sample. The viruses were grouped according to their distance from the surface of lamellae and reconstructed. Damage to the approximately 20-nm-thick outermost lamella surface was similar to that from exposure to 16 e-/Å2 in a 300-kV cryo-electron microscope at high-resolution range. The damage was negligible at a depth beyond 50 nm, which was reduced to 30 nm if 8-keV Ga+ was used during polishing. We designed extra steps in the reconstruction refinement to maximize undamaged signals and increase the resolution. The results demonstrated that low-energy beam polishing was essential for high-quality thinner lamellae.

9.
Fish Shellfish Immunol ; 139: 108906, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37348686

RESUMO

Synthetic phenolic antioxidants (SPAs) are an environmental concern due to their persistence nature and bioaccumulation. However, the hepatoxicity and mechanisms of SPAs in aquatic organisms remain poorly understood. In this study, grass carp were exposed to two representative SPAs (BHA and BHT) at environmentally relevant levels (0.1 µM) for 30 days. We observed that BHA and BHT exposure significantly increased the levels of serum aminotransferase (ALT) and aspartate aminotransferase (AST) in grass carp, accompanied by mild inflammatory cell infiltration and irregularity in the shape of hepatocytes. Dihydro ethylenediamine staining showed that BHA and BHT exposure resulted in elevated levels of superoxide levels, accompanied by increased antioxidant enzyme activities (T-AOC, SOD, CAT, GSH-PX) and MDA levels, which is suggestive of oxidative stress responses in the liver of grass carp. Besides, BHA and BHT could dock into the pocket of phosphatidylinositol 3-kinases (PI3K) and thereby inhibiting PI3K/mammalian target of rapamycin (mTOR)/protein kinase B (AKT) signaling cascades. Meanwhile, our results clarified that BHA and BHT could promote autophagosome production and increase the expression of key autophagy proteins, likely due to inhibition of PI3K/mTOR/AKT signaling pathway. Moreover, BHA and BHT could induce apoptotic process by upregulating the expression of Bax, Caspase3 and Caspase8 and downregulating Bcl2 expression. Notably, BHT exhibited more hepatoxicity on the indicators of the apoptosis and oxidative stress than BHA. In summary, our findings demonstrated that BHA and BHT exposure could induce liver damage induced via regulating ROS/PI3K-mediated autophagic hyperactivation, which is a crucial step in triggering hepatocyte death. This study provides novel insight into the potential mechanisms underlying liver damage caused by BHA and BHT in aquatic organisms, and offers a new theoretical basis for ecological risk assessment of SPAs.


Assuntos
Antioxidantes , Carpas , Animais , Antioxidantes/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Sirolimo , Carpas/metabolismo , Fenóis , Apoptose , Autofagia , Serina-Treonina Quinases TOR/metabolismo , Mamíferos/metabolismo
10.
Int J Mol Sci ; 24(4)2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36835348

RESUMO

ZnIn2S4, a novel two-dimensional visible light-responsive photocatalyst, has attracted much attention in the photocatalytic evolution of H2 under visible light irradiation due to its attractive intrinsic photoelectric properties and geometric configuration. However, ZnIn2S4 still has severe charge recombination, which results in moderate photocatalytic performance. Herein, we report the successful synthesis of 2D/2D ZnIn2S4/Ti3C2 nanocomposites by a facile one-step hydrothermal method. The efficiency of the nanocomposites in photocatalytic hydrogen evolution under visible light irradiation was also evaluated for different ratios of Ti3C2, and the optimal photocatalytic activity was achieved at 5% Ti3C2. Importantly, the activity was significantly higher than that of pure ZnIn2S4, ZnIn2S4/Pt, and ZnIn2S4/graphene. The enhanced photocatalytic activity is mainly due to the close interfacial contact between Ti3C2 and ZnIn2S4 nanosheets, which amplifies the transport of photogenerated electrons and enhances the separation of photogenerated carriers. This research describes a novel approach for the synthesis of 2D MXenes for photocatalytic hydrogen production and expands the utility of MXene composite materials in the fields of energy storage and conversion.


Assuntos
Grafite , Titânio , Elétrons , Hidrogênio
11.
Virol J ; 20(1): 29, 2023 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-36782252

RESUMO

BACKGROUND: Systemic lupus erythematosus (SLE) is a complex autoimmune disease, and the etiology is still unclear. Some studies have indicated that viral infection might contribute to the development of SLE. METHODS: A total of 105 individuals with SLE and 110 matched healthy controls were tested for EBV-specific DNA fragments in peripheral blood monocytes by PCR-Southern blotting. The expression of EBV-encoded genes was determined by RT-PCR and Southern blotting in EBV-positive patients. Serum EBV-specific IgM antibody was determined by ELISA. HHV-6 DNA in peripheral blood monocytes of those SLE patients and normal controls was tested by nested PCR. RESULTS: Statistical analysis showed that the EBV-positive rate of SLE patients was significantly higher than that of the control group (χ2 = 87.329, P = 0), while the difference in the HHV-6-positive rate between the two groups was not significant (P > 0.05). An association of EBV and HHV-6 positivity in SLE patients was found (P = 0, r = 0.38). The EBV IgM level was significantly higher in SLE patients than in healthy controls (χ2 = 25.184, P = 0). Forty-two of the 75 EBV DNA-positive specimens were positive for EBNA2 mRNA, and an association between EBV EBNA2 mRNA and anti-Sm antibody positivity was found (P = 0, r = 0.409). LMP1 mRNA was positive in 2 SLE patients with active phase, and no LMP2A mRNA expression was detected in EBV DNA-positive specimens. EBV early gene BARF1 mRNA was detected in 2 cases of EBV-positive SLE patients, and these 2 patients were also HHV-6 DNA positive. Thirty-eight patients were BcLF1 mRNA positive, and 33 of them were HHV-6 positive as well. These factors were associated (χ2 = 15.734, P = 0). The expression of the EBV immediate early gene BZLF1 was negative in all 75 EBV-positive SLE patients. CONCLUSIONS: The results suggest that EBV infection might be related to the occurrence of SLE. Although there is no direct evidence that HHV-6 infection is associated with the development of SLE, EBV and HHV-6 infection may have a coacceleration effect in SLE patients. This study provides a new theoretical and experimental basis for the study of viral etiology and the prevention and treatment of SLE.


Assuntos
Infecções por Vírus Epstein-Barr , Herpesvirus Humano 6 , Lúpus Eritematoso Sistêmico , Infecções por Roseolovirus , Humanos , Herpesvirus Humano 4/genética , Herpesvirus Humano 6/genética , Proteínas Virais/genética , Infecções por Roseolovirus/complicações , Lúpus Eritematoso Sistêmico/complicações , Lúpus Eritematoso Sistêmico/epidemiologia , Anticorpos Antivirais , RNA Mensageiro
12.
Ecotoxicol Environ Saf ; 253: 114655, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36812867

RESUMO

Imidacloprid (IMI) is among the common neonicotinoid insecticides used in agriculture worldwide, posing a potential toxic threat to non-target animals and humans. Numerous studies have shown that ferroptosis is involved in the pathophysiological progression of renal diseases. However, it remains unclear whether ferroptosis is involved in IMI-induced nephrotoxicity. In the present study, we investigated the potential pathogenic role of ferroptosis in IMI-induced kidney damage in vivo. Transmission electron microscopy (TEM) showed that the mitochondrial crest of kidney cells significantly decreased following IMI exposure. Moreover, IMI exposure triggered ferroptosis and lipid peroxidation in the kidney. We confirmed that nuclear factor erythroid 2-related factor 2 (Nrf2)-mediated antioxidant capability was negatively correlated with the ferroptosis induced by IMI exposure. Importantly, we verified that NOD-, LRR-, and pyrin domain-containing protein 3 (NLRP3)-driven inflammation occurred in the kidneys following IMI exposure, but pretreatment with the ferroptosis inhibitor ferrostatin (Fer-1) blocked this phenomenon. Additionally, IMI exposure induced F4/80+ macrophages to accumulated in the proximal tubules of the kidneys, and also increased the protein expression of high-mobility group box 1 (HMGB1), receptor for advanced glycation end products (RAGE), receptor for advanced glycation end products (TLR4), and nuclear factor kappa-B (NF-κB). In contrast, inhibition of ferroptosis by Fer-1 blocked IMI-induced NLRP3 inflammasome activation, F4/80 positive macrophages, and the HMGB1-RAGE/TLR4 signaling pathway. To the best of our knowledge, this is the first study to reveal that IMI stress can induce Nrf2 inactivation, thereby triggering ferroptosis, causing an initial wave of death, and activating HMGB1-RAGE/TLR4 signaling, which promotes pyroptosis that perpetuates kidney dysfunction.


Assuntos
Ferroptose , Proteína HMGB1 , Animais , Humanos , NF-kappa B/metabolismo , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Receptor 4 Toll-Like/metabolismo , Piroptose , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Proteína HMGB1/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Transdução de Sinais , Neonicotinoides/toxicidade
13.
Exp Appl Acarol ; 89(1): 45-60, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36635606

RESUMO

Exogenous application of methyl jasmonate (MeJA) could activate plant defense response against the two-spotted spider mite (TSSM), Tetranychus urticae Koch, in different plants. However, whether MeJA can also serve as an elicitor in cassava (Manihot esculenta Crantz) remains unknown. In this study, induced defense responses were investigated in TSSM-resistant cassava variety C1115 and TSSM-susceptible cassava variety KU50 when applied with MeJA. The performance of TSSM feeding on cassava plants that were pre-treated with various concentrations of MeJA was first evaluated. Subsequently, the activities of antioxidative enzymes (superoxide dismutase and catalase), detoxification enzymes (glutathione S-transferase, cytochrome P450 and carboxylesterase) and digestive enzymes (protease, amylase and invertase) in TSSM were analyzed at days 1, 2, 4 and 8 post-feeding. The results showed that MeJA treatment can induce cassava defense responses to TSSM in terms of reducing egg production and adult longevity as well as slowing development and prolonging the egg stage. Noticeably, C1115 exhibited stronger inhibition of TSSM development and reproduction than KU50. In addition, the activities of all the tested enzymes were induced in both C1115 and KU50, the most in C1115. We conclude that exogenous methyl jasmonate can induce cassava defense responses and enhance resistance to TSSM.


Assuntos
Manihot , Tetranychidae , Animais , Manihot/fisiologia , Tetranychidae/fisiologia , Antioxidantes , Acetatos/farmacologia , Verduras
14.
Structure ; 31(2): 213-220.e3, 2023 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-36586403

RESUMO

For cryoelectron microscopy (cryo-EM), high cooling rates have been required for preparation of protein samples to vitrify the surrounding water and avoid formation of damaging crystalline ice. Whether and how crystalline ice affects single-particle cryo-EM is still unclear. Here, single-particle cryo-EM was used to analyze three-dimensional structures of various proteins and viruses embedded in crystalline ice formed at various cooling rates. Low cooling rates led to shrinkage deformation and density distortions on samples having loose structures. Higher cooling rates reduced deformations. Deformation-free proteins in crystalline ice were obtained by modifying the freezing conditions, and reconstructions from these samples revealed a marked improvement over vitreous ice. This procedure also increased the efficiency of cryo-EM structure determinations and was essential for high-resolution reconstructions.


Assuntos
Gelo , Proteínas , Microscopia Crioeletrônica/métodos , Água
15.
Front Plant Sci ; 13: 1054909, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36570903

RESUMO

Introduction: Utilization of resistant germplasm is considered as an effective, economical and eco-friendly strategy for cassava pest management. Tetranychus urticae, known as the two-spotted spider mite (TSSM), is a devastating pest in Asian cassava planting countries as well as in China. However, the resistant levels of abundant cassava germplasms to TSSM remains largely unknown. Methods: To fill this knowledge gap, we conducted screening of 202 cassava germplasm for resistance to TSSM in China based on the classification of mite damage phenotype, under both greenhouse and field conditions. Results: The three rounds of large-scale greenhouse experiments had identified two highly resistant (HR) varieties (C1115 and MIANDIAN), five resistant (R) varieties (SC5, SC9, SC15, COLUMBIA-4D and LIMIN) and five highly susceptible (HS) varieties (KU50, BREAD, SC205, TMS60444 and BRA900), besides, these 'HR' and 'R' varieties would significantly repress the normal development and reproduction of TSSM. In addition, the 12 cassava varieties selected from the greenhouse screening were further subjected to consecutive five years of field validation at Danzhou, Wuming and Baoshan. The seven resistant varieties not only exhibited stable TSSM-resistance performance across the three field environments, but also possessed the same resistant levels as the greenhouse identification, while the resistant varieties SC5 was an exception, which was identified as moderate resistant in Baoshan, indicating the variety-environment interaction may affect its resistance. Furthermore, regional yield estimation suggested that the higher the resistance level was, the better capacity in reducing the yield losses. Discussion: This study demonstrated that the TSSM-resistant varieties could be considered as ideal materials in mite control or in future breeding programme of mite-resistant cassava plant.

16.
J Insect Sci ; 22(6)2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36545895

RESUMO

Methyl jasmonate (MeJA) is a phytohormone that has been used to artificially induce plant resistance against multiple arthropod herbivores. However, it is still uncertain whether MeJA can trigger pepper plant resistance against Myzus persicae (Sulzer) (Hemiptera: Aphididae) (green peach aphid, GPA). In this study, we assessed the effects of different concentrations (0, 0.008, 0.04, 0.2, 1.0, and 5.0 mM) of MeJA-treated pepper on the development and reproduction performance of GPA to identify an appropriate concentration for vigorous resistance enhancement. MeJA dose was applied on the pepper to investigate the changes in activities of protective enzyme (superoxide dismutase, SOD; catalase, CAT; peroxidase, POD and polyphenol oxidase, PPO), detoxification enzymes (acetylcholinesterase, AchE; glutathione S-transferase, GSTs; cytocrome P450, CYP450, and carboxylesterase, CarE), and digestive enzymes (protease, PRO and amylase, AMY) in GPA. The results showed that all concentrations of MeJA-treated pepper significantly suppressed GPA performance, wherein 0.2 mM was the optimal concentration, as it presented the lowest intrinsic rate of increase (rm), finite rate of increase (λ), and the highest population doubling time (Dt) values. Furthermore, the protective enzymes (SOD and CAT), detoxification enzymes (GSTs, CYP450, and CarE), and AMY activities increased significantly in MeJA-treated groups than the control group, while the POD and PPO activities were remarkly inhibited under 0.2 mM treatment. These findings indicate that exogenous spraying of 0.2 mM of MeJA significantly enhanced pepper resistance against GPA. The result of this study suggests MeJA application can be used as a promising strategy in integrative management of this insect pest.


Assuntos
Afídeos , Capsicum , Animais , Acetilcolinesterase , Superóxido Dismutase
17.
Nat Commun ; 13(1): 5363, 2022 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-36097007

RESUMO

cAMP is a key second messenger that regulates diverse cellular functions including neural plasticity. However, the spatiotemporal dynamics of intracellular cAMP in intact organisms are largely unknown due to low sensitivity and/or brightness of current genetically encoded fluorescent cAMP indicators. Here, we report the development of the new circularly permuted GFP (cpGFP)-based cAMP indicator G-Flamp1, which exhibits a large fluorescence increase (a maximum ΔF/F0 of 1100% in HEK293T cells), decent brightness, appropriate affinity (a Kd of 2.17 µM) and fast response kinetics (an association and dissociation half-time of 0.20 and 0.087 s, respectively). Furthermore, the crystal structure of the cAMP-bound G-Flamp1 reveals one linker connecting the cAMP-binding domain to cpGFP adopts a distorted ß-strand conformation that may serve as a fluorescence modulation switch. We demonstrate that G-Flamp1 enables sensitive monitoring of endogenous cAMP signals in brain regions that are implicated in learning and motor control in living organisms such as fruit flies and mice.


Assuntos
Diagnóstico por Imagem , Sistemas do Segundo Mensageiro , Animais , Corantes , Proteínas de Fluorescência Verde/genética , Células HEK293 , Humanos , Camundongos
18.
Front Plant Sci ; 13: 994866, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36061805

RESUMO

The two-spotted spider mite (TSSM) is a destructive cassava pest. Intensive demonstration of resistance mechanism greatly facilitates the creation of TSSM-resistant cassava germplasm. Gene to metabolite network plays a crucial role in modulating plant resistance, but little is known about the genes and related metabolites which are responsible for cassava resistance to TSSM. Here, a highly resistant (HR) and a highly susceptible (HS) cassava cultivar were used, integrative and comparative transcriptomic and metabolomic analyses between these two cultivars after TSSM infestation revealed that several genes and metabolites were closely related and significantly different in abundance. In particular, the expression of leucoanthocyanidin reductase (LAR) and anthocyanidin reductase (ANR) genes showed a high positive correlation with most of the metabolites in the tannin biosynthesis pathway. Furthermore, transgenic cassava lines overexpressing either of the genes elevated tannin concentrations and conferred cassava resistance to TSSM. Additionally, different forms of tannins possessed distinct bioactivity on TSSM, of which total condensed tannins (LC50 = 375.68 mg/l) showed maximum lethal effects followed by procyanidin B1 (LC50 = 3537.10 mg/l). This study accurately targets LAR, ANR and specific tannin compounds as critical genes and metabolites in shaping cassava resistance to TSSM, which could be considered as biomarkers for evaluation and creation of pest-resistant cassava germplasm.

19.
Cell Rep ; 40(7): 111229, 2022 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35977515

RESUMO

Learning induces the formation of new synapses in addition to changes of existing synapse strength. However, it remains unclear whether new synapses serve different functions from existing synapses. By performing two-photon structural and Ca2+ imaging of postsynaptic dendritic spines in layer 2/3 pyramidal neurons, we show that new spine formation increases in the mouse motor cortex 8-24 h after motor training. New spines, not existing spine populations, are preferentially active when mice perform the learned task rather than a new task. New spine activity is also more synchronized with dendritic/somatic activity when the learned task, not a new task, is carried out. Furthermore, new spines are formed to increase the task specificity in a subset of neurons, and their survival is not affected when a new task is learned. These findings suggest that newly formed synapses preferentially increase the task specificity of neurons over existing synapses at the retention stage of motor learning.


Assuntos
Espinhas Dendríticas , Plasticidade Neuronal , Animais , Espinhas Dendríticas/fisiologia , Aprendizagem/fisiologia , Camundongos , Plasticidade Neuronal/fisiologia , Células Piramidais/fisiologia , Sinapses/fisiologia
20.
Curr Oncol ; 29(8): 5383-5406, 2022 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-36005165

RESUMO

Exosomes, extracellular vesicles with a diameter of 40 to 160 nm, are among the smallest extracellular vesicles released by cells. They deliver different cargoes, including proteins, DNAs, and RNAs, and facilitate communication between cells to coordinate a variety of physiological and pathological functions. Hepatocellular carcinoma (HCC) is the sixth common malignant tumor and the fourth leading cause of cancer-related death worldwide. Its molecular mechanism remains largely unknown, and there is a lack of reliable and noninvasive biomarkers for early diagnosis and prognosis prediction. Mounting evidence has shown that exosomes carry a variety of ncRNAs, such as long non-coding RNAs (lncRNAs), microRNAs (miRNAs), and circular RNAs (circRNAs), which play critical roles in the occurrence and progression of HCC. In this review, we summarize the recent findings of exosomal miRNAs, lncRNAs, and circRNAs in HCC from their impact on the development of HCC to their potential applications in the diagnosis and treatment of HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , MicroRNAs , RNA Longo não Codificante , Biologia , Carcinoma Hepatocelular/genética , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/genética , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Circular , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo
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