Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 34
Filtrar
Más filtros










Base de datos
Intervalo de año de publicación
1.
PLoS One ; 19(5): e0303235, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38728287

RESUMEN

Excitotoxicity represents the primary cause of neuronal death following spinal cord injury (SCI). While autophagy plays a critical and intricate role in SCI, the specific mechanism underlying the relationship between excitotoxicity and autophagy in SCI has been largely overlooked. In this study, we isolated primary spinal cord neurons from neonatal rats and induced excitotoxic neuronal injury by high concentrations of glutamic acid, mimicking an excitotoxic injury model. Subsequently, we performed transcriptome sequencing. Leveraging machine learning algorithms, including weighted correlation network analysis (WGCNA), random forest analysis (RF), and least absolute shrinkage and selection operator analysis (LASSO), we conducted a comprehensive investigation into key genes associated with spinal cord neuron injury. We also utilized protein-protein interaction network (PPI) analysis to identify pivotal proteins regulating key gene expression and analyzed key genes from public datasets (GSE2599, GSE20907, GSE45006, and GSE174549). Our findings revealed that six genes-Anxa2, S100a10, Ccng1, Timp1, Hspb1, and Lgals3-were significantly upregulated not only in vitro in neurons subjected to excitotoxic injury but also in rats with subacute SCI. Furthermore, Hspb1 and Lgals3 were closely linked to neuronal autophagy induced by excitotoxicity. Our findings contribute to a better understanding of excitotoxicity and autophagy, offering potential targets and a theoretical foundation for SCI diagnosis and treatment.


Asunto(s)
Autofagia , Galectina 3 , Aprendizaje Automático , Neuronas , Animales , Neuronas/metabolismo , Ratas , Galectina 3/metabolismo , Galectina 3/genética , Ratas Sprague-Dawley , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Médula Espinal/metabolismo , Médula Espinal/patología , Traumatismos de la Médula Espinal/metabolismo , Traumatismos de la Médula Espinal/patología , Traumatismos de la Médula Espinal/genética , Mapas de Interacción de Proteínas , Ácido Glutámico/metabolismo , Proteínas de Choque Térmico/metabolismo , Proteínas de Choque Térmico/genética
2.
Chem Biol Interact ; 395: 111014, 2024 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-38648921

RESUMEN

There is an increasing appreciation that colonic barrier function is closely related to the development and progression of colitis. The mucus layer is a crucial component of the colonic barrier, responsible for preventing harmful bacteria from invading the intestinal epithelium and causing inflammation. Furthermore, a defective mucus barrier is also a significant characteristic of ulcerative colitis (UC). Biochanin A (BCA), an isoflavonoid, has garnered increasing interest due to its significant biological activities. However, the impact of BCA on UC has not been reported yet. In this study, we used a dextran sodium sulfate (DSS)-induced ulcerative colitis model and the Muc2 deficient (Muc2-/-) mice spontaneous colitis model to explore the mechanisms of BCA in the treatment of UC. Here, we verified that DSS-induced UC was observably attenuated and spontaneous colitis in Muc2-/- mice was relieved by BCA. Treatment with BCA improved colitis-related symptoms and reduced intestinal permeability by upregulating the levels of goblet cells and tight junction (TJ) proteins. In addition, we confirmed that BCA promotes autophagy through the AMP-activated protein kinase (AMPK)/mammalian target of rapamycin (mTOR)/Unc-51-like kinase 1 (ULK1) pathway, thereby alleviating DSS-induced UC. In addition, the administration of BCA was able to reduce apoptosis and promote proliferation by suppressing Cleaved Caspase-3 (Cleaved Cas-3) expression, and increasing PCNA and Ki67 levels. Further research revealed that BCA treatment ameliorated spontaneous colitis and alleviated epithelial damage in Muc2-/- mice by restoring the intestinal barrier and promoting autophagy. Our results demonstrated that BCA alleviated UC by enhancing intestinal barrier function and promoting autophagy. These findings indicate that BCA may be a novel treatment alternative for UC.


Asunto(s)
Colitis Ulcerosa , Colon , Sulfato de Dextran , Genisteína , Mucina 2 , Animales , Mucina 2/metabolismo , Mucina 2/genética , Sulfato de Dextran/toxicidad , Colitis Ulcerosa/inducido químicamente , Colitis Ulcerosa/tratamiento farmacológico , Colitis Ulcerosa/patología , Colitis Ulcerosa/metabolismo , Genisteína/farmacología , Genisteína/uso terapéutico , Ratones , Colon/patología , Colon/efectos de los fármacos , Colon/metabolismo , Autofagia/efectos de los fármacos , Ratones Endogámicos C57BL , Modelos Animales de Enfermedad , Ratones Noqueados , Apoptosis/efectos de los fármacos , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patología , Masculino , Proteínas Quinasas Activadas por AMP/metabolismo , Serina-Treonina Quinasas TOR/metabolismo
3.
Infect Control Hosp Epidemiol ; : 1-6, 2024 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-38404133

RESUMEN

OBJECTIVE: To evaluate the economic costs of reducing the University of Virginia Hospital's present "3-negative" policy, which continues methicillin-resistant Staphylococcus aureus (MRSA) contact precautions until patients receive 3 consecutive negative test results, to either 2 or 1 negative. DESIGN: Cost-effective analysis. SETTINGS: The University of Virginia Hospital. PATIENTS: The study included data from 41,216 patients from 2015 to 2019. METHODS: We developed a model for MRSA transmission in the University of Virginia Hospital, accounting for both environmental contamination and interactions between patients and providers, which were derived from electronic health record (EHR) data. The model was fit to MRSA incidence over the study period under the current 3-negative clearance policy. A counterfactual simulation was used to estimate outcomes and costs for 2- and 1-negative policies compared with the current 3-negative policy. RESULTS: Our findings suggest that 2-negative and 1-negative policies would have led to 6 (95% CI, -30 to 44; P < .001) and 17 (95% CI, -23 to 59; -10.1% to 25.8%; P < .001) more MRSA cases, respectively, at the hospital over the study period. Overall, the 1-negative policy has statistically significantly lower costs ($628,452; 95% CI, $513,592-$752,148) annually (P < .001) in US dollars, inflation-adjusted for 2023) than the 2-negative policy ($687,946; 95% CI, $562,522-$812,662) and 3-negative ($702,823; 95% CI, $577,277-$846,605). CONCLUSIONS: A single negative MRSA nares PCR test may provide sufficient evidence to discontinue MRSA contact precautions, and it may be the most cost-effective option.

4.
IEEE Rev Biomed Eng ; PP2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38194402

RESUMEN

The shortened radio frequency wavelength in high field MRI makes it challenging to create a uniform excitation pattern over a large field of view, or to achieve satisfactory transmission efficiency at a local area. Transmit arrays are one tool that can be used to create a desired excitation pattern. To be effective, it is important to be able to control the current amplitude and phase at the array elements. The control of the current may get complicated by the coil coupling in many applications. Various methods have been proposed to achieve current control, either in the presence of coupling, or by effectively decouple the array elements. These methods are applied in different subsystems in the RF transmission chain: coil; coil-amplifier interface; amplifier, etc. In this review paper, we provide an overview of the various approaches and aspects of transmit current control and decoupling.

5.
J Orthop Res ; 42(6): 1356-1368, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38245854

RESUMEN

A metabolic bone disease characterized by decreased bone formation and increased bone resorption is osteoporosis. It can cause pain and fracture of patients. The elderly are prone to osteoporosis and are more vulnerable to osteoporosis. In this study, radiomics are extracted from computed tomography (CT) images to screen osteoporosis in the elderly. Collect the plain scan CT images of lumbar spine, cut the region of interest of the image and extract radiomics features, use Lasso regression to screen variables and adjust complexity, use python language to model random forests, support vector machines, K nearest neighbor, and finally use receiver operating characteristic curve to evaluate the performance of the model, including precision, recall, accuracy and area under the curve (AUC). For the model, 14 radiolomics features were selected. The diagnosis performance of random forest model and support vector machine is good, all around 0.9. The AUC of K nearest neighbor model in training set and test set is 0.828 and 0.796, respectively. We selected the plain scan CT images of the elderly lumbar spine to build radiomics features model, which has good diagnostic performance and can be used as a tool to assist the diagnosis of osteoporosis in the elderly.


Asunto(s)
Vértebras Lumbares , Osteoporosis , Máquina de Vectores de Soporte , Tomografía Computarizada por Rayos X , Humanos , Anciano , Osteoporosis/diagnóstico por imagen , Vértebras Lumbares/diagnóstico por imagen , Femenino , Masculino , Anciano de 80 o más Años , Persona de Mediana Edad , Radiómica
6.
Plant Dis ; 2023 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-38127631

RESUMEN

Papaya (Carica papaya L.) belonging to the family Caricaceae is well known for its economic and nutritional value. Anthraconse caused by Colletotrichum spp. is a main postharvest disease of papaya fruit during storage (Cia et al., 2007). In July 2022, papaya fruits with anthracnose symptoms were collected in Changjiang County (108.996180E, 19.246560N), Hainan Province, China. The disease incidence of fruit rot reached 6.3%. Initial symptoms appeared as the watery lesions with tiny black spots, turning to dark brown, sunken necrotic lesions. The diseased tissues were cut into 18 pieces (5×5 mm) from 6 papaya fruits, disinfected with 2% sodium hypochlorite for 60 s, and rinsed three times with sterilized water. The pieces were air-dried and then placed on potato dextrose agar (PDA) at 28 ℃ for five days. Twelve isolates with similar morphology were obtained from 18 tissue pieces. Three isolates (FMG01, FMG02 and FMG03) were selected for morphological identification, molecular identification, and pathogenicity tests. Colonies were initially white, then gradually became dark grey on PDA. The ascospores were hyaline, fusoid, rounded at both ends, 37.43-84.32 (55.79±7.61) µm × 4.30-6.55 (5.36±0.60) µm (n=50). The conidia were hyaline, unicellular, long cylindrical, bluntly rounded at both ends, 11.59-25.54 (18.62±2.33) µm × 5.12-8.44 (7.19±0.62) µm (n=100). Appressoria were gray to dark brown, irregular, pyriform, or ovoid, 10.14-21.40 (13.81±2.25) µm × 6.05-11.85 (9.16±1.29) µm (n=50). Morphological features are similar to Colletotrichum gigasporum identified and described by Rakotoniriana et al (Rakotoniriana et al., 2013). In order to accurately identify the isolates, the internal transcribed spacer region (ITS) of the rDNA, the glyceraldehyde-3-phosphate dehydrogenase (GAPDH), the partial actin (ACT), the beta-tubulin (TUB2) and the calmodulin (CAL) genes were amplified and sequenced (Cannon et al., 2012). The nucleotide sequences were deposited into GenBank (accession numbers, ITS: OR017446 to OR017448, GAPDH: OR042810 to OR042812, ACT: OR042813 to OR042815, TUB2: OR042816 to OR042818, CAL: OR042819 to OR042821). Based on the BLASTn analysis, these sequences were more than 99% with the reference strain CBS 125476 of C. gigasporum sequences (ITS: MH863698, GAPDH: KF687833, ACT: KF687790, TUB2: KF687875, CAL: KF687814), respectively. The results of the multilocal phylogenetic analysis showed that the three isolates were C. gigasporum based on the Maximum Likelihood and Bayesian inference method. The pathogenicity test was performed by wounded with a sterile needle on the surface-sterilized papaya fruits. The mycelial discs (5 mm diameter) of three isolates were inoculated orderly on the same fruit, and the same inoculation was applied to non-wound papaya fruits. The control group were inoculated with sterilized PDA. Each treatment carried out with 9 fruits. The inoculated fruits were placed at 28 ℃ in plastic preservation boxes (32×22×11 cm) with sterilized distilled water to maintain high humidity. After 5 d of inoculation, typical anthracnose symptoms were observed on wound fruits and the non-wound fruits developed symptoms at 7 dpi, control fruits were symptomless. The fungi re-isolated from the inoculated fruits lesions after inoculation and identified by morphological characterization and molecular identification, fulfilling Koch's postulates. C. gigasporum has been reported causing leaf rot of Dalbergia odorifera in China (Wan et al., 2018). To our knowledge, this is the first report of anthracnose fruit rot of papaya caused by C. gigasporum in China.

7.
Macromolecules ; 56(21): 8754-8766, 2023 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-38024153

RESUMEN

The enantiomeric ratio is a key factor affecting the crystallization behavior and morphology of poly-l-lactide/poly-d-lactide (PLLA/PDLA) blends. Despite a number of studies on crystallization of nonequimolar PLLA/PDLA blends, a full picture of the effect of the L/D ratio is still lacking. Here, we put the two enantiomers in contact and allow interdiffusion above the melting point of the stereocomplex crystal (SC) to prepare samples with a continuously changing L/D ratio from enantiopure PLLA (ratio 0/100) to enantiopure PDLA (100/0). Using polarized optical microscopy, atomic force microscopy, and microbeam X-ray diffraction, the continuous spectrum of morphologies and phase behaviors across the contact zone is investigated. The blend morphology shows clear evidence of "poisoning by purity" of SC crystallization at all blend compositions. The low birefringence of the 50/50 SC is found to be due to the meandering of broken edge-on lamellae. Its further decrease to near zero as L/D deviates further away from 50/50 is explained by transition from radial edge-on lamellae to fully random meandering lamellae, then to mixed flat-on lamellae, and finally to submicron-sized axialites. In comparison with the smooth and straight homocrystal (HC) lamellae of pure enantiomers, the lamellae in the blends often have serrated edges caused by pinning by rejected excess enantiomer acting as an impurity during lamellar growth. A feature of the binary phase diagram is pure enantiomers acting as an impurity to the SC and counter-enantiomer acting as an impurity to homocrystallization of the enantiomers. Crystallization was found to be most suppressed at 99% enantiomeric purity, where the amount of the counter-enantiomer is insufficient for creation of SC nuclei and HC growth is inhibited by the small amount of the enantio-impurity. These and other intriguing results are less likely to be noticed without the continuous composition gradient of the contact sample.

8.
Sci Rep ; 13(1): 16197, 2023 09 27.
Artículo en Inglés | MEDLINE | ID: mdl-37758756

RESUMEN

Healthcare-associated infections (HAIs) are a major problem in hospital infection control. Although HAIs can be suppressed using contact precautions, such precautions are expensive, and we can only apply them to a small fraction of patients (i.e., a limited budget). In this work, we focus on two clinical problems arising from the limited budget: (a) choosing the best patients to be placed under precaution given a limited budget to minimize the spread (the isolation problem), and (b) choosing the best patients to release when limited budget requires some of the patients to be cleared from precaution (the clearance problem). A critical challenge in addressing them is that HAIs have multiple transmission pathways such that locations can also accumulate 'load' and spread the disease. One of the most common practices when placing patients under contact precautions is the regular clearance of pathogen loads. However, standard propagation models like independent cascade (IC)/susceptible-infectious-susceptible (SIS) cannot capture such mechanisms directly. Hence to account for this challenge, using non-linear system theory, we develop a novel spectral characterization of a recently proposed pathogen load based model, 2-MODE-SIS model, on people/location networks to capture spread dynamics of HAIs. We formulate the two clinical problems using this spectral characterization and develop effective and efficient algorithms for them. Our experiments show that our methods outperform several natural structural and clinical approaches on real-world hospital testbeds and pick meaningful solutions.


Asunto(s)
Infección Hospitalaria , Humanos , Infección Hospitalaria/prevención & control , Control de Infecciones , Hospitales , Pacientes , Atención a la Salud
9.
Macromolecules ; 56(14): 5502-5511, 2023 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-37521250

RESUMEN

Polymorphism of semicrystalline polymers has significant influence on their physical properties, with each form having its advantages and disadvantages. However, real-life polymer processing often results in different coexisting crystal polymorphs, and it remains a challenge to determine their shape, spatial distribution, and volume fraction. Here, i-polypropylene (i-PP) sheets containing both α- and ß-forms were prepared either by adding ß-nucleating agent or by fiber pulling-induced crystallization. By adding a compatible dye that is partially rejected from the growing crystalline aggregates (spherulites and cylindrites), we visualize the shape of these objects in 3D using two-photon fluorescence confocal microscopy. To distinguish between crystal forms, we take advantage of the difference in dye-retaining ability of the α- and ß-aggregates. Even in 2D, fluorescence microscopy (FM) distinguishes the two crystal forms better than polarized microscopy. In 3D imaging, the volume fraction and spatial distribution of α- and ß-forms in different morphological types could be determined quantitatively. Morphologies described as α-teeth, ß-fans, and α-teardrops were visualized for the first time in 3D. Furthermore, internal and surface microcracks were seen to be associated predominantly with the ß-form and around the fiber. Spatial distribution of α- and ß-forms was also determined by scanning with a synchrotron X-ray beam. Good agreement was obtained with 3D microscopy, but XRD could not match the detail obtainable by the tomography. The work demonstrates the ability of the 3D imaging method to distinguish different crystal forms and their specific morphologies.

10.
Front Bioeng Biotechnol ; 11: 1077490, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36860881

RESUMEN

Due to recalcitrant microangiopathy and chronic infection, traditional treatments do not easily produce satisfactory results for chronic diabetic ulcers. In recent years, due to the advantages of high biocompatibility and modifiability, an increasing number of hydrogel materials have been applied to the treatment of chronic wounds in diabetic patients. Research on composite hydrogels has received increasing attention since loading different components can greatly increase the ability of composite hydrogels to treat chronic diabetic wounds. This review summarizes and details a variety of newly loaded components currently used in hydrogel composites for the treatment of chronic diabetic ulcers, such as polymer/polysaccharides/organic chemicals, stem cells/exosomes/progenitor cells, chelating agents/metal ions, plant extracts, proteins (cytokines/peptides/enzymes) and nucleoside products, and medicines/drugs, to help researchers understand the characteristics of these components in the treatment of diabetic chronic wounds. This review also discusses a number of components that have not yet been applied but have the potential to be loaded into hydrogels, all of which play roles in the biomedical field and may become important loading components in the future. This review provides a "loading component shelf" for researchers of composite hydrogels and a theoretical basis for the future construction of "all-in-one" hydrogels.

11.
Macromolecules ; 56(3): 989-998, 2023 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-36818575

RESUMEN

Formation of stereocomplex crystals (SC) is an effective way to improve the heat resistance and mechanical performance of poly(lactic acid) products. However, at all but the slowest cooling rates, SC crystallization of a high-molecular-weight poly(l-lactic acid)/poly(d-lactic acid) (PLLA/PDLA) racemate stops at a high temperature or does not even start, leaving the remaining melt to crystallize into homochiral crystals (HC) or an SC-HC mixture on continuous cooling. To understand this intriguing phenomenon, we revisit the SC crystallization of both high- and low-molecular-weight PLLA/PDLA racemates. Based on differential scanning calorimetry (DSC), supplemented by optical microscopy and X-ray scattering, we concluded that what stops the growth of SC is the accumulation of the nearly pure enantiomer, either PDLA or PLLA, that is rejected from the SC ahead of its growth front. The excess enantiomer is a result of random compositional fluctuation present in the melt even if the average composition is 1:1. The situation is more favorable if the initial polymer is not fully molten or is brought up to just above the melting point where SC seeds remain, as proven by DSC and X-ray scattering. Moreover, we find that not only is SC growth poisoned by the locally pure enantiomer but also that at lower temperatures, the HC growth can be poisoned by the blend. This explains why SC growth, arrested at high temperatures, can resume at lower temperatures, along with the growth of HC. Furthermore, while some previous works attributed the incomplete SC crystallization to a problem of primary nucleation, we find that adding a specific SC-promoting nucleating agent does not help alleviate the problem of cessation of SC crystallization. This reinforces the conclusion that the main problem is in growth rather than in nucleation.

12.
Macromolecules ; 56(1): 198-206, 2023 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-36644554

RESUMEN

Two-photon confocal laser microscopy was used to obtain three-dimensional (3D) images of the morphology of poly(lactic acid) after shear-induced crystallization. The necessary fluorescence contrast was achieved by doping the polymer with Nile Red. The dye gets partially rejected from the growing crystalline aggregates during their formation, thus creating a renderable high-low fluorescence boundary outlining the shape of the aggregates. Parallel-plate melt-shearing and pulling a glass fiber through the melt were used as the two methods to achieve shear-induced crystallization. This study focuses on the shape of the resulting cylindrites, i.e., large-diameter shish-kebabs. The first 3D images of polymer cylindrites show that, if far from boundaries, they are circular cylinders, highly regular after fiber pull, but less so after parallel-plate shear. In the latter case, the cylindrite reveals the trajectory of the foreign particle that had nucleated its growth. Interestingly, lateral growth of the cylindrites was found to accelerate toward the sample surface when approaching it, giving the cylindrite an elliptical cross section. Furthermore and surprisingly, in the case of fiber pull, a row of spherulites is nucleated at the polymer-substrate interface nearest to the fiber, aligned along the fiber axis and appearing ahead of the rest of the space-filling spherulites. Both the phenomena, elliptical cylindrites and row of spherulites, are attributed to negative pressure buildup peaking at the cylindrite growth front and at the nearby film surface caused by crystallization-induced volume contraction. The pressure and flow distribution in the system is confirmed by numerical simulation. The results illustrate the value of 3D imaging of crystalline morphology in polymer science and polymer processing industry.

13.
Neurosci Bull ; 39(1): 57-68, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35713844

RESUMEN

PiT2 is an inorganic phosphate (Pi) transporter whose mutations are linked to primary familial brain calcification (PFBC). PiT2 mainly consists of two ProDom (PD) domains and a large intracellular loop region (loop7). The PD domains are crucial for the Pi transport, but the role of PiT2-loop7 remains unclear. In PFBC patients, mutations in PiT2-loop7 are mainly nonsense or frameshift mutations that probably cause PFBC due to C-PD1131 deletion. To date, six missense mutations have been identified in PiT2-loop7; however, the mechanisms by which these mutations cause PFBC are poorly understood. Here, we found that the p.T390A and p.S434W mutations in PiT2-loop7 decreased the Pi transport activity and cell surface levels of PiT2. Furthermore, we showed that these two mutations attenuated its membrane localization by affecting adenosine monophosphate-activated protein kinase (AMPK)- or protein kinase B (AKT)-mediated PiT2 phosphorylation. In contrast, the p.S121C and p.S601W mutations in the PD domains did not affect PiT2 phosphorylation but rather impaired its substrate-binding abilities. These results suggested that missense mutations in PiT2-loop7 can cause Pi dyshomeostasis by affecting the phosphorylation-regulated cell-surface localization of PiT2. This study helps understand the pathogenesis of PFBC caused by PiT2-loop7 missense mutations and indicates that increasing the phosphorylation levels of PiT2-loop7 could be a promising strategy for developing PFBC therapies.


Asunto(s)
Mutación Missense , Fosfatos , Proteínas Cotransportadoras de Sodio-Fosfato de Tipo III , Humanos , Membrana Celular , Fosfatos/metabolismo , Proteínas Cotransportadoras de Sodio-Fosfato de Tipo III/genética
14.
Plant Physiol Biochem ; 191: 99-109, 2022 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-36201884

RESUMEN

Leaf senescence is regulated by both endogenous hormones and environmental stimuli in a programmed and concerted way. The members of the S40 family have been reported to play roles in leaf senescence. Here we identified an S40 family member, CiS40-11, from Caragana intermedia. Phylogenetic analysis revealed that the CiS40-11 protein had the highest identity with AtS40-5 (AT1G11700) and AtS40-6 (AT1G61930) of Arabidopsis thaliana. CiS40-11 was highly expressed in leaves and was down-regulated after dark treatment. The subcellular localization analysis showed that CiS40-11 was a cytoplasm-nucleus dual-localized protein. Leaf senescence was delayed in both the CiS40-11 overexpressed A. thaliana and its transiently expressed C. intermedia. Transcriptomic analysis and endogenous hormones assay revealed that CiS40-11 inhibited leaf senescence via promoting the biosynthesis of cytokinins by blocking AtMYB2 expression in the CiS40-11 overexpression lines. Furthermore, overexpression of either AtS40-5 or AtS40-6 showed similar phenotype as the CiS40-11 overexpressing lines, while in the ats40-5a or ats40-6a mutants, the AtMYB2 expression was increased and their leaves exhibited a premature senescence phenotype. These results provide a new molecular mechanism of the S40 family in leaf senescence regulation of plants.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Citocininas/metabolismo , Regulación de la Expresión Génica de las Plantas , Hormonas/metabolismo , Filogenia , Hojas de la Planta/metabolismo , Senescencia de la Planta , Plantas Modificadas Genéticamente/metabolismo
15.
Front Cell Dev Biol ; 10: 935795, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36158222

RESUMEN

Anterior cruciate ligament injury is the most common sports injury in orthopaedics, which can adversely affect knee joint function and exercise of patients. Using arthroscopy to reconstruct the anterior cruciate ligament has become the first choice for treating anterior cruciate ligament rupture. However, different degrees of articular cartilage injury of the knee can be observed in patients after anterior cruciate ligament reconstruction. More importantly, the articular cartilage injury after anterior cruciate ligament reconstruction indicates that it will develop into osteoarthritis in the long term. It is of great significance to fully understand the factors that lead to the occurrence and development of cartilage injury. This article reviews the effects of surgical methods, meniscus status, different grafts, time from injury to surgical intervention, postoperative knee joint stability, postoperative rehabilitation, knee joint anatomical factors, and demographic characteristics of patients on articular cartilage degeneration after anterior cruciate ligament reconstruction. The present review provides insights into the anterior cruciate ligament reconstruction, which can be used to investigate new treatment strategies to delay and prevent the progress of osteoarthritis. At the same time, it provides a holistic understanding of the influence of multiple factors on cartilage lesions after anterior cruciate ligament reconstruction.

16.
Micromachines (Basel) ; 13(6)2022 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-35744460

RESUMEN

A high-property plasma resonance-sensor structure consisting of two metal-insulator-metal (MIM) waveguides coupled with a transverse ladder-shaped nano-cavity (TLSNC) is designed based on surface plasmon polaritons. Its transmission characteristics are analyzed using multimode interference coupling mode theory (MICMT), and are simulated using finite element analysis (FEA). Meanwhile, the influence of different structural arguments on the performance of the structure is investigated. This study shows that the system presents four high-quality formants in the transmission spectrum. The highest sensitivity is 3000 nm/RIU with a high FOM* of 9.7 × 105. In addition, the proposed structure could act as a biosensor to detect the concentrations of sodium ions (Na+), potassium ions (K+), and the glucose solution with maximum sensitivities of 0.45, 0.625 and 5.5 nm/mgdL-1, respectively. Compared with other structures, the designed system has the advantages of a simple construction, a wide working band range, high reliability and easy nano-scale integration, providing a high-performance cavity choice for refractive index sensing and biosensing devices based on surface plasmons.

17.
Eur Spine J ; 30(8): 2311-2322, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33871706

RESUMEN

PURPOSE: To investigate the perioperative complications of lateral anterior lumbar interbody fusion (LaLIF) surgery. METHODS: The participants were patients who underwent LaLIF surgery for degenerative lumbar diseases between April 2016 and November 2020. The collected data were classified into intraoperative and early-stage postoperative (1 month) complications. Intraoperative complications were subcategorized into nerve root injury, sympathetic chain injury, segmental artery injury, iliolumbar vein injury, peritoneum laceration, temporary psoas injury, endplate damage, and vertebral body fractures. Postoperative complications were subcategorized into surgical site infection, cage migration, cage subsidence and psoas major hematoma. RESULTS: In the 255 included patients, 39 complications (15.3%) were reported. One patient (0.4%) had residual neurological symptoms (numbness) at the last follow-up after conservative management. The most common complications were temporary psoas injury (3.9%), followed by sympathetic chain injury (2.7%) and endplate damage (2.0%). The most frequent postoperative complication was cage migration (1.6%), followed by cage subsidence (1.2%), and surgical site infection (0.8%). CONCLUSION: The complication rates for LaLIF are generally low and comparable to those for conventional OLIF and XLIF that have been reported in other studies. Almost all complications were transient after LaLIF. Severe complications can be avoided by using sufficient muscle relaxant, instruments with the required characteristics and vertical trajectories in multiple steps.


Asunto(s)
Fracturas de la Columna Vertebral , Fusión Vertebral , Humanos , Complicaciones Intraoperatorias/epidemiología , Complicaciones Intraoperatorias/etiología , Vértebras Lumbares/cirugía , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Músculos Psoas/diagnóstico por imagen , Estudios Retrospectivos , Fusión Vertebral/efectos adversos
18.
J Orthop Translat ; 28: 12-20, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33575167

RESUMEN

BACKGROUND: Many modified lateral lumbar interbody fusion techniques for lumbar degenerative diseases have been described by different authors. However, relatively high rates of vascular injury, peritoneal laceration, and even ureteral injury have been reported. PURPOSE: The objectives of this study were firstly to present the detailed, standardized technical notes and describe the required standard characteristics of the designed surgical system of LaLIF and secondly to evaluate clinical outcomes and highlight the approach-related complications. METHODS: The mini-open LaLIF is described in a step-wise manner. The outcome measures were operative parameters, self-report measures, radiographic measures, and complications within 1 month of surgery. Operative parameters measured included operative time, intraoperative blood loss, and length of hospital stay. The self-report measures include Visual Analogue Scale (VAS), Oswestry disability index (ODI), and Short Form 36 Health Survey (SF-36) score. The radiographic measures including the intervertebral foraminal height (FH), intervertebral disc height (DH), and intervertebral foraminal area (FA) were assessed with plain radiography. The complication profiles were classified into intraoperative and postoperative (up to 1 month). Intraoperative complications were subcategorized into neurologic, vascular, ureteral, peritoneal, and vertebral injuries. Postoperative complications were subcategorized into infection, cage migration, and subsidence. RESULTS: A total of 126 patients who underwent LaLIF between April 2016 and December 2018 â€‹by a senior author were retrospectively reviewed. There were 54 males and 72 females (range 42-89 â€‹years old, average 65 â€‹± â€‹11 years old). The mean follow-up was 20 â€‹± â€‹11 â€‹months (range 6-38 â€‹months). The LaLIF was conducted at 188 levels in 126 patients, with 1 level in 75 cases, 2 levels in 42, 3 levels in 7, and 4 levels in 2 cases. There were 114 patients who underwent stand-alone LaLIF and 12 patients required secondary posterior fixation. The mean operative time, intraoperative blood loss, and length of hospital stay were recorded. The patient-reported outcome scores (VAS, ODI, and SF-36) and radiographic parameters (FH, DH, and FA) demonstrated a significant improvement after surgery and at the last follow-up. There were 25 (19.8%) complications in the 126 patients. The intraoperative complications accounted for 19 cases (15.1%) and postoperative accounted for 6 cases (4.8%). The most frequent complications were neurological injury (6.3%) and temporary psoas injury (6.3%). CONCLUSIONS: The mini-open LaLIF, as a reproducible novel technique, can be performed safely at L2-L5. It is associated with reliable mid-term clinical outcomes and an acceptable complication profile when compared to traditional LLIF due to the advancements in the modified incision site, direct visualization, and usage of strictly vertical trajectory in multiple steps with the specially designed LaLIF system. TRANSLATIONAL POTENTIAL STATEMENT: To make the lateral lumbar fusion process repeatable and also maintain a shallow learning curve, especially for surgeons in the early stages of learning, by using instruments with the required standard characteristics, the standardized surgical steps, modified incision site, vertical trajectory, and the direct visualization during the entire procedure.

19.
Eur Spine J ; 30(1): 97-107, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32816081

RESUMEN

PURPOSE: To analyze correlations between the realistic surgical difficulty of LaLIF and anatomic characteristics in radiographic images, in order to develop a simple classification to provide guiding information for case selection and evaluate the potential risks of the technique. METHODS: Ninety-six consecutive cases who underwent LaLIF surgeries at the L4-5 level with MR T2-weighted images were analyzed. A novel classification based on the anatomic relationships among the disk, great vessels, and psoas muscle was used for grouping. Clinical outcomes and realistic surgical difficulty parameters were recorded, and comparisons were made among different types of classifications. RESULTS: Of the 96 analyzed cases, the time of surgical exposure was significantly longer for type C than for type B, and both of these were longer than that of type A. The VAS and ODI were significantly improved at a 1-year follow-up. There was no statistically significant difference among the three types. Type C had the highest incidence of complications, while Type A had the lowest. Analyses of another 304 MRI cases obtained in outpatient clinics showed that the distribution of the three types among these cases was consistent with that of the surgical cohort. CONCLUSION: Our novel and simple classification provides useful information for case selection. Type A provided the best indication and is most appropriate for a beginner in this technique. Type C includes the most challenging situations, which may have a high incidence of complications and require sophisticated surgical skills to achieve satisfactory outcomes and avoid approach-related complications.


Asunto(s)
Vértebras Lumbares , Fusión Vertebral , Correlación de Datos , Humanos , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/cirugía , Región Lumbosacra , Músculos Psoas
20.
Magn Reson Med ; 85(1): 551-559, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32820540

RESUMEN

PURPOSE: This work describes the construction and evaluation of a bilateral 32-channel receive array for breast imaging at 7T. METHODS: The receive array consisted of 32 receive coils, placed on two 3D-printed hemispherical formers. Each side of the receive array consisted of 16 receive loops, each loop having a corresponding detachable board with match/tune capacitors, active detuning circuitry, and a balun. Coil performance was evaluated on homogeneous canola oil phantoms using a Philips Achieva 7T system. Array coil performance was compared with a bilateral forced current excitation volume coil in transmit/receive mode and with a previously reported 16-channel unilateral coil with a similar design. RESULTS: The 32-channel array had an increase in average SNR throughout both phantoms by a factor of five as compared with the volume coil, with SNR increases up to 10 times along the periphery and three times in the center. Noise measurements showed low interelement noise correlation (average: 5.4%; maximum: 16.8%). Geometry factor maps were acquired for various acceleration factors and showed mean geometry factors <1.2, for combined acceleration factors of up to six. CONCLUSIONS: The improvements achieved demonstrate the clear potential for use in dynamic contrast-enhanced or diffusion-weighted MR studies, while maintaining diagnostically relevant spatial and temporal resolutions.


Asunto(s)
Mama , Imagen por Resonancia Magnética , Mama/diagnóstico por imagen , Diseño de Equipo , Fantasmas de Imagen , Relación Señal-Ruido , Análisis Espectral
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...