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1.
Planta ; 260(2): 48, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38980389

RESUMO

MAIN CONCLUSION: We studied the D3-type cyclin function during gynoecium development in Arabidopsis and how they are related to the hormone cytokinin and the transcription factor SPATULA. Growth throughout the life of plants is sustained by cell division and differentiation processes in meristematic tissues. In Arabidopsis, gynoecium development implies a multiphasic process where the tissues required for pollination, fertilization, and seed development form. The Carpel Margin Meristem (CMM) is a mass of undifferentiated cells that gives rise to the gynoecium internal tissues, such as septum, ovules, placenta, funiculus, transmitting tract, style, and stigma. Different genetic and hormonal factors, including cytokinin, control the CMM function. Cytokinin regulates the cell cycle transitions through the activation of cell cycle regulators as cyclin genes. D3-type cyclins are expressed in proliferative tissues, favoring the mitotic cell cycle over the endoreduplication. Though the role of cytokinin in CMM and gynoecium development is highly studied, its specific role in regulating the cell cycle in this tissue remains unclear. Additionally, despite extensive research on the relationship between CYCD3 genes and cytokinin, the regulatory mechanism that connects them remains elusive. Here, we found that D3-type cyclins are expressed in proliferative medial and lateral tissues. Conversely, the depletion of the three CYCD3 genes showed that they are not essential for gynoecium development. However, the addition of exogenous cytokinin showed that they could control the division/differentiation balance in gynoecium internal tissues and outgrowths. Finally, we found that SPATULA can be a mechanistic link between cytokinin and the D3-type cyclins. The data suggest that the role of D3-type cyclins in gynoecium development is related to the cytokinin response, and they might be activated by the transcription factor SPATULA.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Fatores de Transcrição Hélice-Alça-Hélice Básicos , Citocininas , Flores , Regulação da Expressão Gênica de Plantas , Citocininas/metabolismo , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Flores/crescimento & desenvolvimento , Flores/genética , Flores/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Ciclina D3/metabolismo , Ciclina D3/genética , Meristema/genética , Meristema/crescimento & desenvolvimento , Meristema/metabolismo , Ciclinas
2.
BMC Ophthalmol ; 24(1): 311, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39054506

RESUMO

Vascular conjunctival tumors are uncommon, usually benign lesions. Here, we report a 65-year-old male who presented with a nasal interpalpebral bulbar firm, oval, and dark-brown and non-mobile conjunctival mass. The systemic and ocular examinations including fundoscopy and gonioscopy were within normal limits. With a diagnosis of conjunctival malignant melanoma (CMM), the patient underwent excisional biopsy, partial sclerectomy, and cryotherapy. Microscopic examination revealed dilated vascular channels filled by red blood cells, separated by fibrous interstitium and no sign of malignancy. Therefore, a diagnosis of conjunctival cavernous hemangioma was made. Our case demonstrates that the conjunctival cavernous hemangioma can mimic malignant conjunctival lesions as well as extrascleral extension of uveal melanoma or uveal prolapse due to scleral necrosis.


Assuntos
Neoplasias da Túnica Conjuntiva , Hemangioma Cavernoso , Humanos , Masculino , Idoso , Hemangioma Cavernoso/diagnóstico , Hemangioma Cavernoso/patologia , Hemangioma Cavernoso/cirurgia , Neoplasias da Túnica Conjuntiva/diagnóstico , Neoplasias da Túnica Conjuntiva/patologia , Diagnóstico Diferencial , Túnica Conjuntiva/patologia
3.
Sensors (Basel) ; 24(9)2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38733026

RESUMO

In this paper, a six-degree-of-freedom analog tactile probe with a new, simple, and robust mechanical design is presented. Its design is based on the use of one elastomeric ring that supports the stylus carrier and allows its movement inside a cubic measuring range of ±3 mm. The position of the probe tip is determined by three low-cost, noncontact, 2D PSD (position-sensitive detector) sensors, facilitating a wider application of this probe to different measuring systems compared to commercial ones. However, several software corrections, regarding the size and orientation of the three LED light beams, must be carried out when using these 2D sensors for this application due to the lack of additional focusing or collimating lenses and the very wide measuring range. The development process, simulation results, correction models, experimental tests, and calibration of this probe are presented. The results demonstrate high repeatability along the X-, Y-, and Z-axes (2.0 µm, 2.0 µm, and 2.1 µm, respectively) and overall accuracies of 6.7 µm, 7.0 µm, and 8.0 µm, respectively, which could be minimized by more complex correction models.

4.
Int J Mol Sci ; 25(18)2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-39337557

RESUMO

Cutaneous metastatic melanoma (CMM) is the most aggressive form of skin cancer with a poor prognosis. Drug-induced secondary tumorigenesis and the emergency of drug resistance worsen an already worrying scenario, thus rendering urgent the development of new treatments not dealing with mutable cellular processes. Triphenyl phosphonium salts (TPPSs), in addiction to acting as cytoplasmic membrane disruptors, are reported to be mitochondria-targeting compounds, exerting anticancer effects mainly by damaging their membranes and causing depolarization, impairing mitochondria functions and their DNA, triggering oxidative stress (OS), and priming primarily apoptotic cell death. TPP-based bola amphiphiles are capable of self-forming nanoparticles (NPs) with enhanced biological properties, as commonly observed for nanomaterials. Already employed in several other biomedical applications, the per se selective potent antibacterial effects of a TPP bola amphiphile have only recently been demonstrated on 50 multidrug resistant (MDR) clinical superbugs, as well as its exceptional and selective anticancer properties on sensitive and MDR neuroblastoma cells. Here, aiming at finding new molecules possibly developable as new treatments for counteracting CMM, the effects of this TPP-based bola amphiphile (BPPB) have been investigated against two BRAF mutants CMM cell lines (MeOV and MeTRAV) with excellent results (even IC50 = 49 nM on MeOV after 72 h treatment). With these findings and considering the low cytotoxicity of BPPB against different mammalian non-tumoral cell lines and red blood cells (RBCs, selectivity indexes up to 299 on MeOV after 72 h treatment), the possible future development of BPPB as topical treatment for CMM lesions was presumed. With this aim, a biodegradable hyaluronic acid (HA)-based hydrogel formulation (HA-BPPB-HG) was prepared without using any potentially toxic crosslinking agents simply by dispersing suitable amounts of the two ingredients in water and sonicating under gentle heating. HA-BPPB-HA was completely characterized, with promising outcomes such as high swelling capability, high porosity, and viscous elastic rheological behavior.


Assuntos
Proliferação de Células , Ácido Hialurônico , Hidrogéis , Melanoma , Proteínas Proto-Oncogênicas B-raf , Espécies Reativas de Oxigênio , Humanos , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/metabolismo , Hidrogéis/química , Hidrogéis/farmacologia , Melanoma/tratamento farmacológico , Melanoma/patologia , Melanoma/metabolismo , Ácido Hialurônico/química , Ácido Hialurônico/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Mutação , Nanopartículas/química , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/patologia
5.
Pain Pract ; 24(1): 109-119, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37661347

RESUMO

OBJECTIVE: The MOTION study is designed to measure the impact of percutaneous image-guided lumbar decompression as a first-line therapy on patients otherwise receiving real-world conventional medical management for lumbar spinal stenosis with neurogenic claudication secondary to hypertrophic ligamentum flavum. This prospective, multicenter randomized controlled trial uses objective and patient-reported outcome measures to compare the combination of the mild® percutaneous treatment and nonsurgical conventional medical management (CMM) to CMM-Alone. METHODS: Test group patients received the mild procedure after study enrollment. Test and control groups were allowed conventional conservative therapies and low-risk interventional therapies as recommended by their physicians. Subjective outcomes included the Oswestry Disability Index, Numeric Pain Rating Scale, and Zurich Claudication Questionnaire. Objective outcomes included a validated Walking Tolerance Test, the rate of subsequent lumbar spine interventions, and safety data. RESULTS: Two-year follow-up included 64 mild + CMM and 67 CMM-Alone patients. All outcome measures showed significant improvement from baseline for mild + CMM, whereas the majority of CMM-Alone patients had elected to receive mild treatment or other lumbar spine interventions by 2 years, precluding valid 2-year between-group comparisons. Neither group reported any device- or procedure-related adverse events. CONCLUSIONS: The durability of mild + CMM for this patient population was demonstrated for all efficacy outcomes through 2 years. Improvements in walking time from baseline to 2 years for patients treated with mild + CMM were significant and substantial. The lack of reported device or procedure-related adverse events reinforces the strong safety profile of the mild procedure. These results provide support for early interventional treatment of symptomatic LSS with the mild procedure.


Assuntos
Estenose Espinal , Humanos , Seguimentos , Estudos Prospectivos , Estenose Espinal/complicações , Estenose Espinal/cirurgia , Descompressão Cirúrgica/métodos , Vértebras Lombares/cirurgia , Resultado do Tratamento
6.
Zhongguo Zhong Yao Za Zhi ; 49(13): 3409-3413, 2024 Jul.
Artigo em Zh | MEDLINE | ID: mdl-39041112

RESUMO

This article outlined the composition and species characteristics of Chinese materia medica(CMM) resources identified in the fourth national survey of CMM resources. The survey was conducted based on field investigations and office collation, adhering to the "four principles", which emphasized the existence of survey records, voucher specimens, actual photographs, and evidence of medicinal use, so as to summarize the species of CMM resources and ensure the scientific integrity and accuracy of the results. According to the results, China had a total of 18 817 CMM resources, including 15 321 medicinal plants, 826 medicinal fungi, 2 517 medicinal animals, and 153 medicinal minerals. Additionally, the fourth national survey of CMM resources also conducted specialized investigations on 3 151 species of unique medicinal plants, 464 species of rare and endangered medicinal plants, and 196 new species in China. These latest statistics on these CMM resources will provide the most up-to-date foundational data for the protection, management, development, and utilization of these resources over an extended period, offering scientific guidance for the development of the traditional Chinese medicine(TCM) industry.


Assuntos
Materia Medica , Plantas Medicinais , China , Plantas Medicinais/química , Plantas Medicinais/classificação , Plantas Medicinais/crescimento & desenvolvimento , Medicina Tradicional Chinesa , Medicamentos de Ervas Chinesas , Animais , Conservação dos Recursos Naturais
7.
Sensors (Basel) ; 23(2)2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36679393

RESUMO

Advances in the scientific fields of photogrammetry and computer vision have led to the development of automated multi-image methods that solve the problem of 3D reconstruction. Simultaneously, 3D scanners have become a common source of data acquisition for 3D modeling of real objects/scenes/human bodies. This article presents a comprehensive overview of different 3D modeling technologies that may be used to generate 3D reconstructions of outer or inner surfaces of different kinds of targets. In this context, it covers the topics of 3D modeling using images via different methods, it provides a detailed classification of 3D scanners by additionally presenting the basic operating principles of each type of scanner, and it discusses the problem of generating 3D models from scans. Finally, it outlines some applications of 3D modeling, beyond well-established topographic ones.


Assuntos
Imageamento Tridimensional , Fotogrametria , Humanos , Imageamento Tridimensional/métodos , Fotogrametria/métodos
8.
Zhongguo Zhong Yao Za Zhi ; 48(6): 1691-1699, 2023 Mar.
Artigo em Zh | MEDLINE | ID: mdl-37005857

RESUMO

Slicing is critical in the processing of Chinese materia medica(CMM) processed product and the specification(thickness) is closely related to the quality of the decoction. On the basis of clarifying the concept and evolution of slicing of CMM processed product by reviewing the Chinese herbal classics of the past dynasties and general rules of local processing standards, this study discussed the development history of slicing specifications in general rules of Chinese Pharmacopoeia(2020 edition), analyzed the current situation and key problems, and proposed the thinking and suggestion on promoting the sound development of slicing of CMM processed product. Since 2000, the slicing thickness of CMM processed product in the general rules of local CMM processed product processing specifications newly revised and issued by 27 provinces, autonomous regions, and municipalities has been consistent with that in the general rules of the Chinese Pharmacopoeia(2020 edition). The standard that the thickness of extremely thin pieces is less than 0.5 mm is rarely retained, and the pieces in 0.5-1 mm thickness have not been found on the market, which is consistent with the provisions of the general rules of the Chinese Pharmacopoeia. This study can provide a historical and modern basis for the rationality of slicing of CMM processed product.


Assuntos
Medicamentos de Ervas Chinesas , Materia Medica , Medicina Tradicional Chinesa , Padrões de Referência
9.
Zhongguo Zhong Yao Za Zhi ; 47(13): 3675-3680, 2022 Jul.
Artigo em Zh | MEDLINE | ID: mdl-35850822

RESUMO

The internationalization of traditional Chinese medicine(TCM) is one of the strategic development objectives in China, which has been incorporated into the national strategy as an important part of the Belt and Road Initiative development strategy. As the basis and prerequisite of TCM development, Chinese materia medica(CMM) has a direct impact on the internationalization of TCM. The International Organization for Standardization(ISO) is a global organization composed of national standardization bodies, and the ISO standards impact the world's economy, trade, communication and cooperation. Based on a brief introduction to ISO/Traditional Chinese Medicine Technical Committee(ISO/TC 249), this study elaborates the necessity of establishing ISO standards for CMM and analyzes the current status and challenges faced by the formulation of international standards for CMM. Finally, this study puts forward the development strategy of international standards for CMM. Specifically, efforts should be made to develop top-level design with international market demands as the guidance and improve the quality of standards to accelerate the transformation of domestic high-quality standards into international standards. Moreover, measures should be taken to give full play to the positive role of enterprises in the formulation of standards, vigorously cultivate compound talents for international standardization of TCM, and constantly strengthen international cooperation. The experience and thinking are of guiding significance for the scientific, efficient and reasonable formulation of high-quality ISO standards for CMM in the future.


Assuntos
Medicamentos de Ervas Chinesas , Materia Medica , China , Humanos , Medicina Tradicional Chinesa , Padrões de Referência
10.
Sensors (Basel) ; 20(8)2020 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-32340325

RESUMO

Trigger probes are widely used in precision manufacturing industries such as coordinate measuring machines (CMM) and high-end computer numerical control(CNC) machine tools for quality control. Their performance and accuracy often determine the measurement results and the quality of the product manufacturing. However, because there is no accurate measurement of the trigger force in different directions of the probe, and no special measuring device to calibrate the characteristic parameters of the probe in traditional measurement methods, it is impossible to exactly compensate for the measurement error caused by the trigger force of the probe in the measurement process. The accuracy of the measurement of the equipment can be improved by abiding by the Abbé principle. Thus, in order to better evaluate the performance parameters of the probe and realize the accurate compensation for its errors, this paper presents a method which can directly measure the performance parameters of the trigger probe based on the Abbé measurement principle, expounds the measurement principle, the establishment of the mathematical model, and the calibration system, and finishes with an experimental verification and measurement uncertainty analysis. The experimental results show that this method can obtain the exact calibration errors of the performance parameters of the trigger probe intuitively, realize the compensation for the errors of the probe in the measurement process, and effectively improve the measurement accuracy.

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