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Terahertz scattering scanning near-field optical microscopy is a robust spectral detection technique with a nanoscale resolution. However, there are still major challenges in investigating the heterogeneity of cell membrane components in individual cells. Here, we present a novel and comprehensive analytical approach for detecting and investigating heterogeneity in cell membrane components at the single-cell level. In comparison to the resolution of the topographical atomic force microscopy image, the spatial resolution of the terahertz near-field amplitude image is 3 times that of the former. This ultrafine resolution enables the compositional distribution in the cell membrane, such as the distribution of extracellular vesicles, to be finely characterized. Furthermore, via extraction of the near-field absorption images at specific frequencies, the visualization and compositional difference analysis of cell membrane components can be presented in detail. These findings have significant implications for the intuitive and visual analysis of cell development and disease evolutionary pathways.
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Membrana Celular , Análisis de la Célula Individual , Análisis de la Célula Individual/métodos , Membrana Celular/química , Humanos , Imágen por Terahertz/métodos , Microscopía de Fuerza Atómica/métodos , Vesículas Extracelulares/químicaRESUMEN
Metasurfaces have provided a flexible platform for designing ultracompact metalenses with unusual functionalities. However, traditional multi-foci metalenses are limited to generating circularly polarized (CP) or linearly polarized (LP) focal points, and the intensity distributions are always inhomogeneous/chaotical between the multiple focal points. Here, an inverse design approach is proposed to optimize the in-plane orientation of each meta-atom in a terahertz (THz) multi-foci metalens that can generate multi-polarized focal points with nearly uniform intensity distributions. As a proof-of-principle example, we numerically and experimentally demonstrate an inversely designed metalens for simultaneously generating multiple CP- and LP-based focal points with homogeneous intensity distributions, leading to a multi-polarized image (rather than the holography). Furthermore, the multi-channel and multi-polarized images consisting of multiple focal points with homogeneous intensity distributions are also numerically demonstrated. The unique approach for inversely designing multi-foci metalens that can generate multi-polarized focal points and images with uniform intensity distributions will enable potential applications in imaging and sensing.
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The plasma filament induced by photo-ionization in transparent media (e.g., air) is a competitive terahertz (THz) source, whose mechanism has been widely studied in two separate schemes, i.e., the one- or two-color femtosecond laser filamentation. However, the physical commonality of these two schemes is less explored currently, and a common theory is in urgent need. Here, we proposed the traveling-wave antenna (TWA) model applicable to both single- and dual-color laser fields, which successfully reproduced the reported far-field THz angular distribution/dispersion from different filament lengths with either a constant or a varied plasma density. This work paves the way toward a deeper understanding of the important laser-filament-based THz sources within the same theoretical framework.
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Low-cost broadband photodetectors (PDs) based on group-IV materials are highly demanded. Herein, a vertical all group-IV graphene-i-n (Gr-i-n) structure based on sputtering-grown undoped Ge0.92Sn0.08/Ge multiple quantum wells (MQWs) on n-Ge substrate was proposed to realize efficient visible/shortwave infrared (VIS/SWIR) dual-band photoresponse. Harnessing Gr-germanium tin (GeSn)/Ge MQWs van der Waals heterojunctions, an extended surface depletion region was established, facilitating separation and transportation of photogenerated carriers at VIS wavelengths. Consequently, remarkable VIS/SWIR dual-band response ranging from 400 to 2000â nm with a rapid response time of 23â µs was achieved. Compared to the PD without Gr, the external quantum efficiency at 420, 660, and 1520â nm was effectively enhanced by 10.2-, 5.2-, and 1.2-fold, reaching 40, 42, and 50%, respectively. This research paves the way for the advancement of all group-IV VIS/SWIR broadband PDs and presents what we believe to be a novel approach to the design of low-cost broadband PDs.
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BACKGROUND: Thyroid cancer (TC) frequently manifests with lung metastases in the pediatric population, occurring at a significant rate of 30 %. This study aims to evaluate the impact of regional patterns of cervical lymph node metastases on lung metastases in pediatric TC. METHODS: Retrospective analysis was conducted on data from pediatric TC patients spanning the years 2000 to 2018. We compared the rates of lymph node metastasis (LNR), the number of lymph node metastases, and the number of dissected lymph nodes in the central and lateral cervical regions between patients with and without lung metastases. Statistical methods were employed to adjust for confounders during hypothesis testing. RESULTS: A total of 227 pediatric patients, with a median age of 15.12 ± 2.84 years, were included in the study. Of these, 202 (89 %) exhibited LN metastasis, with 40(17.62 %) patients presenting with lung metastasis. Patients with lung metastases were found to be younger (13.40 ± 3.11 vs. 15.50 ± 2.64, p < 0.001), had larger primary tumor diameters (3.49 ± 1.98 vs. 2.31 ± 1.45, p < 0.001), and exhibited a higher number of lymph node metastases (23.40 ± 10.75 vs. 14.65 ± 13.16, p < 0.001). Notably, in patients with LN metastases, the presence of >12 lateral cervical lymph node metastases emerged as a significant risk factor for lung metastases. Among children with metachronous lung metastases, the median time to detection of lung metastases was 43 (12-132) months, and they appeared to receive a greater proportion of radioactive iodine (RAI) treatment compared to those with synchronous lung metastases. CONCLUSION: Lateral cervical lymph node metastasis independently predicts the likelihood of lung metastases in pediatric TC. Furthermore, our findings emphasize the importance of thorough examination of the lungs during follow-up, particularly when the number of metastatic lateral cervical lymph nodes exceeds 12.
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Carcinoma Papilar , Neoplasias Pulmonares , Neoplasias de la Tiroides , Humanos , Niño , Adolescente , Neoplasias de la Tiroides/patología , Metástasis Linfática/patología , Estudios Retrospectivos , Correlación de Datos , Radioisótopos de Yodo , Tiroidectomía/métodos , Carcinoma Papilar/patología , Ganglios Linfáticos/patología , Neoplasias Pulmonares/patologíaRESUMEN
BACKGROUND: Humeral head replacement (HHR) is now rarely recommended for complex proximal humeral fractures (PHFs) in older patients. However, in relatively young and active patients with unreconstructable complex PHFs, controversy still exists regarding the treatment options of reverse shoulder arthroplasty and HHR. The goal of this study was to compare the survival, functional, and radiographic outcomes of HHR in patients aged <70 years and those aged ≥70 years after a minimum 10 years follow-up. METHODS: Eighty-seven out of 135 patients undergoing primary HHR were enrolled and then divided into 2 groups based on age: <70 years and ≥70 years. Clinical and radiographic evaluations were performed with a minimum follow-up of 10 years. RESULTS: There were 64 patients (mean, 54.9 years) in the younger group and 23 patients (mean, 73.5 years) in the older group. The younger and older groups had comparable 10-year implant survivorship (98.4% vs. 91.3%). Patients aged ≥70 years had worse American Shoulder and Elbow Surgeons scores (74.2 vs. 81.0, P = .042) and lower satisfaction rates (12% vs. 64%, P < .001) than younger patients. At the final follow-up, older patients had worse forward flexion (117° vs. 129°, P = .047) and internal rotation (17 vs. 15, P = .036). More greater tuberosity complications (39% vs. 16%, P = .019), glenoid erosion (100% vs. 59%, P = .077), and humeral head superior migration (80% vs. 31%, P = .037) were also identified in patients aged ≥70 years. CONCLUSIONS: Unlike the increased risk for revision and functional deterioration over time after reverse shoulder arthroplasty for PHFs in younger patients, a high implant survival rate with lasting pain relief and stable functional outcomes could be observed in younger patients after HHR during long-term follow-up. Patients aged ≥70 years had worse clinical outcomes, lower patient satisfaction, more greater tuberosity complications, and more glenoid erosion and humeral head superior migration than those aged <70 years. HHR should not be recommended for the treatment of unreconstructable complex acute PHFs in older patient populations.
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Artroplastía de Reemplazo de Hombro , Artroplastia de Reemplazo , Fracturas del Hombro , Articulación del Hombro , Humanos , Anciano , Cabeza Humeral/cirugía , Estudios de Seguimiento , Articulación del Hombro/diagnóstico por imagen , Articulación del Hombro/cirugía , Resultado del Tratamiento , Estudios de Cohortes , Fracturas del Hombro/diagnóstico por imagen , Fracturas del Hombro/cirugía , Fracturas del Hombro/etiología , Estudios Retrospectivos , Rango del Movimiento ArticularRESUMEN
An equalizer based on a recurrent neural network (RNN), especially with a bidirectional gated recurrent unit (biGRU) structure, is a good choice to deal with nonlinear damage and inter-symbol interference (ISI) in optical communication systems because of its excellent performance in processing time series information. However, its recursive structure prevents the parallelization of the computation, resulting in a low equalization rate. In order to improve the speed without compromising the equalization performance, we propose a minimalist 1D convolutional neural network (CNN) equalizer, which is reconverted from a biGRU with knowledge distillation (KD). In this work, we applied KD to regression problems and explain how KD helps students learn from teachers in solving regression problems. In addition, we compared the biGRU, 1D-CNN after KD and 1D-CNN without KD in terms of Q-factor and equalization velocity. The experimental data showed that the Q-factor of the 1D-CNN increased by 1 dB after KD learning from the biGRU, and KD increased the RoP sensitivity of the 1D-CNN by 0.89 dB with the HD-FEC threshold of 1 × 10-3. At the same time, compared with the biGRU, the proposed 1D-CNN equalizer reduced the computational time consumption by 97% and the number of trainable parameters by 99.3%, with only a 0.5 dB Q-factor penalty. The results demonstrate that the proposed minimalist 1D-CNN equalizer holds significant promise for future practical deployments in optical wireless communication systems.
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Despite its important role in understanding ultrafast spin dynamics and revealing novel spin/orbit effects, the mechanism of the terahertz (THz) emission from a single ferromagnetic nanofilm upon a femtosecond laser pump still remains elusive. Recent experiments have shown exotic symmetry, which is not expected from the routinely adopted mechanism of ultrafast demagnetization. Here, by developing a bidirectional pump-THz emission spectroscopy and associated symmetry analysis method, we set a benchmark for the experimental distinction of the THz emission induced by various mechanisms. Our results unambiguously unveil a new mechanismâanomalous Nernst effect (ANE) induced THz emission due to the ultrafast temperature gradient created by a femtosecond laser. Quantitative analysis shows that the THz emission exhibits interesting thickness dependence where different mechanisms dominate at different thickness ranges. Our work not only clarifies the origin of the ferromagnetic-based THz emission but also offers a fertile platform for investigating the ultrafast optomagnetism and THz spintronics.
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Drought stress is one of the most severe natural disasters in terms of its frequency, length, impact intensity, and associated losses, making it a significant threat to agricultural productivity. Sorghum (Sorghum bicolor), a C4 plant, shows a wide range of morphological, physiological, and biochemical adaptations in response to drought stress, paving the way for it to endure harsh environments. In arid environments, sorghum exhibits enhanced water uptake and reduced dissipation through its morphological activity, allowing it to withstand drought stress. Sorghum exhibits physiological and biochemical resistance to drought, primarily by adjusting its osmotic potential, scavenging reactive oxygen species, and changing the activities of its antioxidant enzymes. In addition, certain sorghum genes exhibit downregulation capabilities in response to drought stress. Therefore, in the current review, we explore drought tolerance in sorghum, encompassing its morphological characteristics and physiological mechanisms and the identification and selection of its functional genes. The use of modern biotechnological and molecular biological approaches to improving sorghum resistance is critical for selecting and breeding drought-tolerant sorghum varieties.
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Sequías , Regulación de la Expresión Génica de las Plantas , Especies Reactivas de Oxígeno , Sorghum , Factores de Transcripción , Sorghum/genética , Sorghum/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Estrés Fisiológico/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Adaptación Fisiológica/genéticaRESUMEN
Electrocatalytic reduction of nitrate to ammonia provides a green alternate to the Haber-Bosch method, yet it suffers from sluggish kinetics and a low yield rate. The nitrate reduction follows a tandem reaction of nitrate reduction to nitrite and subsequent nitrite hydrogenation to generate ammonia, and the ammonia Faraday efficiency (FE) is limited by the competitive hydrogen evolution reaction. Herein, we design a heterostructure catalyst to remedy the above issues, which consists of Ni nanosphere core and Ni(OH)2 nanosheet shell (Ni/Ni(OH)2). In situ Raman spectroscopy reveals Ni and Ni(OH)2 are interconvertible according to the applied potential, facilitating the cascade nitrate reduction synergistically. Consequently, it attains superior electrocatalytic nitrate reduction performance with an ammonia FE of 98.50 % and a current density of 0.934â A cm-2 at -0.476â V versus reversible hydrogen electrode, and exhibits an average ammonia yield rate of 84.74â mg h-1 cm-2 during the 102-hour stability test, which is highly superior to the reported catalysts tested under similar conditions. Density functional theory calculations corroborate the synergistic effect of Ni and Ni(OH)2 in the tandem reaction of nitrate reduction. Moreover, the Ni/Ni(OH)2 catalyst also possesses good capability for methanol oxidation and thus is used to establish a system coupling with nitrate reduction.
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Recently, the concept of core-anti-resonant reflection (CARR) has been proposed, greatly expanding the options of cladding materials and morphologies for Fabry-Perot-type (F-P) cavities. For instance, a single-layer tube made of A4 paper can be a precision resonator in the terahertz (THz) band, which seemed counterintuitive before. More importantly, thanks to the involvement of paper-like materials as the cavity plates, it is possible to equip the CARR cavity with the currently popular origami functionality. Following this clue, in this work we combined a simple octagonal paper tube with different origami patterns and realized the programmable adjustment for the distance between two parallel surfaces of the tubular cavity. Accordingly, the combination of the CARR cavity and the origami property offers a new degree of freedom and flexibility to vary the cavity distance, tune the resonant frequency, and explore related applications. For applied examples, we carried out pressure sensing with this foldable structure and achieved a high sensitivity (S = 57.9 kPa-1). Meanwhile, the origami cavity could also act as a THz polarization converter, and the output polarization state of the cavity mode was easily modulated from the original linear to circular polarizations with different chiralities. In future works, besides the pressure-driven method used here, heat and magnetism, etc., can further be employed to tune the CARR cavity, benefiting from four dimensional (4D) or soft-magneto origami materials as the cavity wall.
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The dynamic control of magnetization by short laser pulses has recently attracted interest. The transient magnetization at the metallic magnetic interface has been investigated through second-harmonic generation and the time-resolved magneto-optical effect. However, the ultrafast light-driven magneto-optical nonlinearity in ferromagnetic heterostructures for terahertz (THz) radiation remains unclear. Here, we present THz generation from a metallic heterostructure, Pt/CoFeB/Ta, which is ascribed to an â¼6-8% contribution from the magnetization-induced optical rectification and an â¼94-92% contribution from both spin-to-charge current conversion and ultrafast demagnetization. Our results show that THz-emission spectroscopy is a powerful tool to study the picosecond-time-scale nonlinear magneto-optical effect in ferromagnetic heterostructures.
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OBJECTIVE: This study aims to develop a CT-based method for quantifying tracheal shape and evaluating its ability to distinguish between cases with or without tracheal invasion in patients with thyroid carcinoma. METHODS: A total of 116 quantitative shape features, including 56 geometric moments and 60 bounding shape features, were defined. The tracheal lumen was semi-automatically defined with a CT threshold of less than - 500 HU. Three contiguous slices with the 1st, 2nd, and 3rd smallest trachea lumen areas were contiguously selected, and the appropriate number of slices to be included was determined. Fifty-six patients with differentiated thyroid carcinoma (DTC) invading the trachea and 22 patients with DTC but without invasion were retrospectively included. A receiver operating characteristic (ROC) curve was applied to select the representative shape features and determine the optimal threshold. RESULTS: 23.3%, 25.9%, and 24.1% of the features displayed an area under the ROC curve (AUC) ≥ 0.800 when derived from 1, 2, and 3 slices, respectively. Calculating feature values from two slices with the 1st and 2nd smallest tracheal lumen area were considered appropriate. Six final features, including 3 geometric moments and 3 bounding shape features, were selected to determine the tracheal invasion status of DTC and displayed AUCs of 0.875-0.918, accuracies of 0.821-0.891, sensitivities of 0.813-0.893, and specificities of 0.818-0.932, outperforming the visual evaluation results. CONCLUSIONS: Geometric moments and bounding shape features can quantify the tracheal shape and are reliable for identifying DTC tracheal invasion. The selected features quantified the extent of tracheal deformity in DTC patients with and without tracheal invasion. CLINICAL RELEVANCE STATEMENT: Six geometric features provide a non-invasive, semi-automated evaluation of the tracheal invasion status of thyroid cancer. KEY POINTS: ⢠A novel method for quantifying tracheal shape using 56 geometric moments and 60 bounding shape features was developed. ⢠Six features identify tracheal invasion by thyroid carcinoma. ⢠The selected features quantified the extent of tracheal deformity in differentiated thyroid carcinoma patients with and without tracheal invasion.
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BACKGROUND: Proximal humeral fractures (PHFs) often occur in elderly individuals who experience low-energy falls. Open reduction and internal fixation (ORIF) of the proximal humerus is typically performed in young, active patients because of their good bone quality and high functional demands. Although good short-term results have been reported after ORIF in young patients, few studies have specifically evaluated long-term outcomes. QUESTIONS/PURPOSES: (1) What are the long-term clinical outcomes scores and (2) radiologic outcomes of nonosteoporotic three-part and four-part PHFs treated with locking plates? (3) What complications occurred after treatment, and what factors are associated with poor postoperative functional outcomes scores and avascular necrosis (AVN) of the humeral head after ORIF? METHODS: Between June 2005 and December 2012, we surgically treated 774 patients for displaced two-, three-, and four-part PHFs. Approximately 75% (581 of 774) underwent ORIF, 10% (77 of 774) underwent hemiarthroplasty, 7% (54 of 774) underwent intramedullary nailing, 5% (39 of 774) underwent reverse shoulder arthroplasty, and the remaining 3% (23 of 774) underwent other surgical treatments. We considered those who had ORIF as potentially eligible. Based on that criterion, 75% (581) were eligible. However, only patients with nonosteoporotic three- and four-part PHFs (cortical thickness of the proximal humeral diaphysis greater than 6 mm on a preoperative AP radiograph of the affected shoulder) and a minimum of 10 years of follow-up were included. Sixty-four percent (498 of 774) of the patients were excluded because of simple or osteoporotic fractures, 1% (7 of 774) were excluded because of ipsilateral limb multiple fractures, 0.3% (2 of 774) were excluded because of pathologic PHFs, and another 2% (13 of 774) were lost before the minimum study follow-up of 10 years, leaving 8% (61 of 774) for analysis here. The mean age at surgery was 45 ± 12 years, with a mean follow-up of 13 years. Fifty-seven percent (35 of 61) of the patients were men. Patient-reported outcomes were evaluated using the University of California Loas Angeles (UCLA) score (range 0 to 35; higher scores represent better shoulder function) and Constant score (range 0 to 100; higher scores represent better shoulder function) at least 10 years postoperatively. Postoperative radiographs were reviewed to assess the cortical bone thickness of the proximal humerus, neck-shaft angle, head-to-tuberosity distance, and radiologically confirmable complications. Logistic regression analysis was performed to evaluate factors associated with poor postoperative functional scores (UCLA score ≤ 27 or Constant score ≤ 70) and AVN of the humeral head; the association between AVN and postoperative functional outcomes was also assessed. RESULTS: At the most-recent follow-up, these patients had a mean UCLA score of 31 ± 3 and a Constant score of 88 ± 10. The mean neck-shaft angle was 133° ± 10°, and 23% (14 of 61) of patients experienced AVN of the humeral head during follow-up. Twenty-nine complications in 30% (18 of 61) of patients were reported. After controlling for potentially confounding variables such as age and gender, we found that the presence of greater tuberosity malposition (odds ratio 18 [95% confidence interval 2 to 167]; p = 0.01) and immediate postoperative neck-shaft angle less than 130° (OR 19 [95% CI 3 to 127]; p = 0.002) were associated with poor postoperative functional scores. Four-part PHFs (OR 13 [95% CI 2 to 82]; p = 0.008) and metaphyseal extension less than 8 mm (OR 7 [95% CI 1 to 35]; p = 0.03) were associated with AVN of the humeral head. For patients who met the criteria for anatomic reduction (achievement of all of the following three criteria: neck-shaft angle ≥ 130°, head-shaft displacement < 5 mm, and head-to-tuberosity distance greater than or equal to 3 mm and less than or equal to 20 mm), there were no differences in postoperative functional scores between patients with AVN and those without. CONCLUSION: ORIF of nonosteoporotic proximal humeral fractures with locking plates led to favorable functional and radiologic outcomes at a minimum of 10 years of follow-up. When encountering complex PHFs in patients with good bone quality, every effort must be made to achieve an anatomic reduction of the fracture as far as possible, which may not reduce the risk of AVN (this occurred in nearly one-fourth of patients). However, good outcomes can usually be expected, even in patients with AVN. Because this was a retrospective study with a high risk of bias owing to sparse data, the factors associated with poor postoperative functional outcomes must be further investigated in large prospective studies. LEVEL OF EVIDENCE: Level III, therapeutic study.
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Bladder cancer has a high incidence worldwide accompanies by high recurrent rate after treatment. The emergence of primary or acquired chemotherapy resistance leads to poor efficacy in many cases. To explore the underlying mechanisms of drug resistance, we firstly established a drug-resistant cell model T24/THP by repeated exposure of T24 cells to pirarubicin (THP) whose concentration increases gradually. Non-targeted metabolomics was performed to identify metabolic changes and key metabolism pathways variance in T24/THP cells. Pathway enrichment analysis demonstrated that the arginine and proline metabolic pathway was the most significantly changed pathway, where two representative members of polyamine, putrescine and spermidine were remarkably down regulated in T24/THP. Subsequent experiments further confirmed that ornithine decarboxylase (ODC1) and spermidine synthase (SRM), the key enzymes involved in the synthesis of these compounds, also showed a stable low expression in T24/THP. However, knocking down of ODC1 and SRM sensitized cells to chemotherapy treatment while overexpression of these two enzymes enhances chemotherapy resistance. This leaded to the point that ODC1 and SRM themselves are more likely to promote the drug resistance, which appears to contradict their low expression in T24/THP. We hypothesize that their diminished levels were due to the declined activity of genes upstream. According to this line of thought, we found that c-MYC was also down-regulated in T24/THP and its content could be significantly affected by drug administration. In addition, c-MYC could not only regulate the expression levels of ODC1 and SRM but also influence drug resistance in T24/THP. In conclusion, alterations in gene expression of ODC1 and SRM in drug resistance cell line is probably mediated by some upstream regulators rather than antineoplastic agents alone. Exploration of upstream signals and research on detailed regulatory mechanism, thereby understanding the actual role of c-MYC and polyamine in response to chemotherapy, can become a potential field direction to overcome drug resistance in bladder cancer.
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Neoplasias de la Vejiga Urinaria , Transportadores de Ácidos Dicarboxílicos , Resistencia a Múltiples Medicamentos , Genes myc , Humanos , Metabolómica , Proteínas de Transporte de Membrana Mitocondrial , Poliaminas/metabolismo , Poliaminas/uso terapéutico , Proteínas Proto-Oncogénicas c-myc , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Neoplasias de la Vejiga Urinaria/genética , Neoplasias de la Vejiga Urinaria/metabolismoRESUMEN
A highly sensitive room-temperature graphene photothermoelectric terahertz detector, with an efficient optical coupling structure of asymmetric logarithmic antenna, was fabricated by planar micro-nano processing technology and two-dimensional material transfer techniques. The designed logarithmic antenna acts as an optical coupling structure to effectively localize the incident terahertz waves at the source end, thus forming a temperature gradient in the device channel and inducing the thermoelectric terahertz response. At zero bias, the device has a high photoresponsivity of 1.54 A/W, a noise equivalent power of 19.8 pW/Hz1/2, and a response time of 900 ns at 105 GHz. Through qualitative analysis of the response mechanism of graphene PTE devices, we find that the electrode-induced doping of graphene channel near the metal-graphene contacts play a key role in the terahertz PTE response. This work provides an effective way to realize high sensitivity terahertz detectors at room temperature.
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PURPOSE: Shoulder hemiarthroplasty (HA) is now rarely indicated for complex proximal humeral fractures due to its unpredictable characteristic of the greater tuberosity (GT) healing. Despite the increasing popularity of reverse shoulder arthroplasty (RSA) in fracture treatment, there are still concerns about failure revision and its application in young populations. The complete negation of HA for fracture treatment is still under debate. METHODS: Eighty-seven out of 135 patients with acute proximal humeral fractures treated with HA were enrolled. Clinical and radiographic evaluations were performed. RESULTS: With a mean follow-up time of 14.7 years, the 10-year prosthetic survival rate was 96.6%. The mean ASES score and Constant score were 79.3 and 81.3, respectively, the mean VAS was 1.1, the average forward flexion was 125.9°, external rotation was 37.2°, and internal rotation was at the L4 level. Nineteen patients (21.8%) displayed GT complications and showed significantly worse outcomes. Glenoid erosion was observed in 64.9% of the patients and resulted in inferior outcomes. The patients who showed good postoperative two year functional outcomes and good acromiohumeral distances usually maintained their results without deterioration over time. CONCLUSIONS: With strict patient selection, a proper surgical technique and closely supervised postoperative rehabilitation, HA could achieve a 96.6% ten year survival rate and good pain relief at an average follow-up of 15 years. Although rarely indicated, HA should have a role in the treatment of acute complex proximal humeral fractures in relatively young and active patients with good GT bone and intact cuff.
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Artroplastía de Reemplazo de Hombro , Hemiartroplastia , Fracturas del Hombro , Articulación del Hombro , Humanos , Hemiartroplastia/efectos adversos , Hemiartroplastia/métodos , Articulación del Hombro/diagnóstico por imagen , Articulación del Hombro/cirugía , Resultado del Tratamiento , Hombro/cirugía , Fracturas del Hombro/diagnóstico por imagen , Fracturas del Hombro/cirugía , Fracturas del Hombro/etiología , Rango del Movimiento Articular , Artroplastía de Reemplazo de Hombro/efectos adversos , Artroplastía de Reemplazo de Hombro/métodos , Estudios RetrospectivosRESUMEN
Colletotrichum higginsianum is a major pathogen causing anthracnose in Chinese flowering cabbage (Brassica parachinensis), posing a significant threat to the Chinese flowering cabbage industry. The conidia of C. higginsianum germinate and form melanized infection structures called appressoria, which enable penetration of the host plant's epidermal cells. However, the molecular mechanism underlying melanin biosynthesis in C. higginsianum remains poorly understood. In this study, we identified two enzymes related to DHN-melanin biosynthesis in C. higginsianum: ChPks and ChThr1. Our results demonstrate that the expression levels of genes ChPKS and ChTHR1 were significantly up-regulated during hyphal and appressorial melanization processes. Furthermore, knockout of the gene ChPKS resulted in a blocked DHN-melanin biosynthetic pathway in hyphae and appressoria, leading to increased sensitivity of the ChpksΔ mutant to cell-wall-interfering agents as well as decreased turgor pressure and pathogenicity. It should be noted that although the Chthr1Δ mutant still exhibited melanin accumulation in colonies and appressoria, its sensitivity to cell-wall-interfering agents and turgor pressure decreased compared to wild-type strains; however, complete loss of pathogenicity was not observed. In conclusion, our results indicate that DHN-melanin plays an essential role in both pathogenicity and cell wall integrity in C. higginsianum. Specifically, ChPks is crucial for DHN-melanin biosynthesis while deficiency of ChThr1 does not completely blocked melanin production.
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Colletotrichum , Melaninas , Virulencia , Melaninas/metabolismo , Pared Celular/metabolismoRESUMEN
Phyto-melatonin improves crop yield by mitigating the negative effects of abiotic stresses on plant growth. Numerous studies are currently being conducted to investigate the significant performance of melatonin in crops in regulating agricultural growth and productivity. However, a comprehensive review of the pivotal performance of phyto-melatonin in regulating plant morpho-physiological and biochemical activities under abiotic stresses needs to be clarified. This review focused on the research on morpho-physiological activities, plant growth regulation, redox status, and signal transduction in plants under abiotic stresses. Furthermore, it also highlighted the role of phyto-melatonin in plant defense systems and as biostimulants under abiotic stress conditions. The study revealed that phyto-melatonin enhances some leaf senescence proteins, and that protein further interacts with the plant's photosynthesis activity, macromolecules, and changes in redox and response to abiotic stress. Our goal is to thoroughly evaluate phyto-melatonin performance under abiotic stress, which will help us better understand the mechanism by which phyto-melatonin regulates crop growth and yield.
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Melatonina , Melatonina/farmacología , Melatonina/metabolismo , Desarrollo de la Planta , Estrés Fisiológico , Productos Agrícolas/metabolismo , FotosíntesisRESUMEN
Cotton growth and yield are severely affected by abiotic stress worldwide. Mepiquate chloride (MC) and melatonin (MT) enhance crop growth and yield by reducing the negative effects of abiotic stress on various crops. Numerous studies have shown the pivotal role of MC and MT in regulating agricultural growth and yield. Nevertheless, an in-depth review of the prominent performance of these two hormones in controlling plant morpho-physiological activity and yield in cotton under abiotic stress still needs to be documented. This review highlights the effects of MC and MT on cotton morpho-physiological and biochemical activities; their biosynthetic, signaling, and transduction pathways; and yield under abiotic stress. Furthermore, we also describe some genes whose expressions are affected by these hormones when cotton plants are exposed to abiotic stress. The present review demonstrates that MC and MT alleviate the negative effects of abiotic stress in cotton and increase yield by improving its morpho-physiological and biochemical activities, such as cell enlargement; net photosynthesis activity; cytokinin contents; and the expression of antioxidant enzymes such as catalase, peroxidase, and superoxide dismutase. MT delays the expression of NCED1 and NCED2 genes involved in leaf senescence by decreasing the expression of ABA-biosynthesis genes and increasing the expression of the GhYUC5, GhGA3ox2, and GhIPT2 genes involved in indole-3-acetic acid, gibberellin, and cytokinin biosynthesis. Likewise, MC promotes lateral root formation by activating GA20x genes involved in gibberellin catabolism. Overall, MC and MT improve cotton's physiological activity and antioxidant capacity and, as a result, improve the ability of the plant to resist abiotic stress. The main purpose of this review is to present an in-depth analysis of the performance of MC and MT under abiotic stress, which might help to better understand how these two hormones regulate cotton growth and productivity.