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1.
IEEE Trans Cybern ; 54(4): 2566-2578, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37318961

RESUMO

This work solves the countermeasure design problems of distributed resilient output time-varying formation-tracking (TVFT) of heterogeneous multiagent systems (MASs) against general Byzantine attacks (GBAs). Inspired by the concept of Digital Twin, a hierarchical protocol equipped with a twin layer (TL) is proposed, which decouples the above problem into the defense against Byzantine edge attacks (BEAs) on the TL and the defense against Byzantine node attacks (BNAs) on the cyber-physical layer (CPL). First, a secure TL with respect to (w.r.t.) the high-order leader dynamics is designed, which achieves resilient estimation against BEAs. A trusted-node strategy against BEAs is proposed, which promotes network resilience by protecting almost the smallest fraction of crucial nodes on the TL. It is proven that strongly (2f+1) -robustness w.r.t. the above trusted nodes is sufficient for the resilient estimation performance of the TL. Second, a decentralized adaptive and chattering-free controller against potentially unbounded BNAs is designed on the CPL. This controller has the merit of uniformly ultimately bounded (UUB) convergence and an assignable exponential decay rate when converging into the above UUB bound. To the best of our knowledge, this article is the first to achieve resilient output TVFT against GBAs, rather than under GBAs. Finally, the practicability and validity of this new hierarchical protocol are illustrated via a simulation example.

2.
Arch. endocrinol. metab. (Online) ; 68: e220491, 2024. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1533663

RESUMO

SUMMARY Primary pigmented nodular adrenocortical disease (PPNAD) is a rare adrenocorticotropin hormone (ACTH)-independent Cushing's syndrome (CS). Pediatric patients with PPNAD typically have unusual skin lesions and slow growth with unknown causes. We present a case of a female Chinese patient with PPNAD caused by the germline PRKACA gene copy number gain of chromosome 19. The patient initially presented with kidney stones, short stature, and obesity. After further testing, it was discovered that the patient had diabetes, mild hypertension, low bone mass, a low ACTH level, and hypercortisolemia, and neither the low-dose or high-dose dexamethasone suppression test was able to inhibit hematuric cortisol, which paradoxically increased. PPNAD was pathologically diagnosed after unilateral adrenalectomy. Chromosome microarrays and whole exon sequencing analyses of the peripheral blood, as well as testing of sectioned adrenal tissue, showed a rise in the copy number of the duplication-containing PRKACA gene on chromosome 19p13.13p13.12, a de novo but not heritable gene defect that causes disease. The clinical signs and symptoms supported the diagnosis of Carney complex (CNC). One significant mechanism of CNC pathogenesis may be the rise in germline PRKACA copy number of chromosome 19. When assessing PPNAD patients for CNC, the possibility of PRKACA gene amplification should be considered. The effect of PRKACA gene amplification on the clinical manifestations of CNC needs to be confirmed by more cases.

3.
World J Psychiatry ; 13(11): 967-972, 2023 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-38073893

RESUMO

BACKGROUND: Cerebrotendinous xanthomatosis (CTX) is a rare autosomal recessive lipid-storage disorder caused by mutations in CYP27A1. Psychiatric manifestations in CTX are rare and nonspecific, and they often lead to considerable diagnostic and treatment delay. CASE SUMMARY: A 33-year-old female patient admitted to the psychiatric ward for presentation of delusions, hallucinations, and behavioral disturbance is reported. The patient presented with cholestasis, cataract, Achilles tendon xanthoma, and cerebellar signs in adulthood and with intellectual disability and learning difficulties in childhood. After the characteristic CTX findings on imaging were obtained, a pathological examination of the Achilles tendon xanthoma was refined. Re-placement therapy was then initiated after the diagnosis was clarified by genetic analysis. During hospitalization in the psychiatric ward, the nonspecific psychiatric manifestations of the patient posed difficulty in diagnosis. After the patient's history of CTX was identified, the patient was diagnosed with organic schizophrenia-like disorder, and psychotic symptoms were controlled by replacement therapy combined with antipsychotic medication. CONCLUSION: Psychiatrists should be aware of CTX, its psychiatric manifestations, and clinical features and avoid misdiagnosis of CTX for timely intervention.

4.
Arch Endocrinol Metab ; 68: e220491, 2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-37988664

RESUMO

Primary pigmented nodular adrenocortical disease (PPNAD) is a rare adrenocorticotropin hormone (ACTH)-independent Cushing's syndrome (CS). Pediatric patients with PPNAD typically have unusual skin lesions and slow growth with unknown causes. We present a case of a female Chinese patient with PPNAD caused by the germline PRKACA gene copy number gain of chromosome 19. The patient initially presented with kidney stones, short stature, and obesity. After further testing, it was discovered that the patient had diabetes, mild hypertension, low bone mass, a low ACTH level, and hypercortisolemia, and neither the low-dose or high-dose dexamethasone suppression test was able to inhibit hematuric cortisol, which paradoxically increased. PPNAD was pathologically diagnosed after unilateral adrenalectomy. Chromosome microarrays and whole exon sequencing analyses of the peripheral blood, as well as testing of sectioned adrenal tissue, showed a rise in the copy number of the duplication-containing PRKACA gene on chromosome 19p13.13p13.12, a de novo but not heritable gene defect that causes disease. The clinical signs and symptoms supported the diagnosis of Carney complex (CNC). One significant mechanism of CNC pathogenesis may be the rise in germline PRKACA copy number of chromosome 19. When assessing PPNAD patients for CNC, the possibility of PRKACA gene amplification should be considered. The effect of PRKACA gene amplification on the clinical manifestations of CNC needs to be confirmed by more cases.


Assuntos
Doenças do Córtex Suprarrenal , Síndrome de Cushing , Humanos , Criança , Feminino , Doenças do Córtex Suprarrenal/genética , Doenças do Córtex Suprarrenal/diagnóstico , Doenças do Córtex Suprarrenal/patologia , Síndrome de Cushing/genética , Adrenalectomia/efeitos adversos , Hidrocortisona , Hormônio Adrenocorticotrópico , Subunidades Catalíticas da Proteína Quinase Dependente de AMP Cíclico
5.
Foods ; 12(13)2023 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-37444353

RESUMO

Chilies undergo multiple stages from field production to reaching consumers, making them susceptible to contamination with foreign materials. Visually similar foreign materials are difficult to detect manually or using color sorting machines, which increases the risk of their presence in the market, potentially affecting consumer health. This paper aims to enhance the detection of visually similar foreign materials in chilies using hyperspectral technology, employing object detection algorithms for fast and accurate identification and localization to ensure food safety. First, the samples were scanned using a hyperspectral camera to obtain hyperspectral image information. Next, a spectral pattern recognition algorithm was used to classify the pixels in the images. Pixels belonging to the same class were assigned the same color, enhancing the visibility of foreign object targets. Finally, an object detection algorithm was employed to recognize the enhanced images and identify the presence of foreign objects. Random forest (RF), support vector machine (SVM), and minimum distance classification algorithms were used to enhance the hyperspectral images of the samples. Among them, RF algorithm showed the best performance, achieving an overall recognition accuracy of up to 86% for randomly selected pixel samples. Subsequently, the enhanced targets were identified using object detection algorithms including R-CNN, Faster R-CNN, and YoloV5. YoloV5 exhibited a recognition rate of over 96% for foreign objects, with the shortest detection time of approximately 12 ms. This study demonstrates that the combination of hyperspectral imaging technology, spectral pattern recognition techniques, and object detection algorithms can accurately and rapidly detect challenging foreign objects in chili peppers, including red stones, red plastics, red fabrics, and red paper. It provides a theoretical reference for online batch detection of chili pepper products, which is of significant importance for enhancing the overall quality of chili pepper products. Furthermore, the detection of foreign objects in similar particulate food items also holds reference value.

6.
Luminescence ; 38(8): 1521-1528, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37296519

RESUMO

To obtain optimal luminescence, 0.12 g of GdVO4 :3%Eu3+ nanocrystals (NCs) and different volumes of nitrogen-doped carbon dots (N-CDs) crude solution were used as precursors, and the composite synthesized using the hydrothermal deposition method showed optimal luminescence when 11 ml (2.45 mmol) crude solution was used. In addition, similar composites with the same molar ratio as GVE/cCDs(11) were also prepared with the hydrothermal and physical mixing processes. Based on the test results of XRD, XPS, and PL spectra, for the composite GVE/cCDs(11), the highest (lowest) peak intensity of the C-C/C=C (C=O/C=N) bond, which was 1.18 (0.75) times that of GVE/cCDs-m, indicated most N-CDs deposition and led to their highest emission intensity under 365 nm excitation, although nitrogen atoms in the composite were shed slightly during the deposition process. Finally, as can be seen from the patterns designed for security applications that the optimally luminescent composite is one of the most promising candidates in the anti-counterfeiting field.


Assuntos
Luminescência , Nanopartículas , Carbono/química , Nitrogênio/química
7.
Brain Behav ; 13(2): e2876, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36621889

RESUMO

OBJECTIVE: Attractin (ATRN) is a widely expressed member of the cell adhesion and guidance protein family in humans that is closely related to cellular immunity and neurodevelopment. However, while previous studies in our laboratory have confirmed the effect of ATRN mutations on long-term memory, its specific role and the molecular mechanism by which it influences spatial cognition are poorly understood. METHODS: This study aimed to examine the effect of ATRN mutations on working memory in water maze with a novel ATRN-mutant rat generated by the CRISPR/Cas9 system; the mutation involved the substitution of the 505th amino acid, glycine (G), with cysteine (C), namely, a mutation from GGC to TGC. The changes in myelin basic protein (MBP) expression in rats were also analyzed with the western blot. RESULTS: The ATRN-G505C(KI/KI) rats exhibited significant increases in the required latency and distance traveled to locate the escape platform in a Morris water maze test of working memory. In addition, the expression of MBP was reduced in ATRN-mutant rats, as shown in the western blot analysis. CONCLUSION: Our results indicate that ATRN gene mutations may directly lead to the impairment of working memory in the water maze; this impairment may be due to the inhibition of MBP expression, which in turn affects the spatial cognition.


Assuntos
Memória de Curto Prazo , Animais , Humanos , Ratos , Aprendizagem em Labirinto , Mutação
8.
Int J Biol Macromol ; 224: 1040-1051, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36283552

RESUMO

Repair of periodontal and maxillofacial bone defects is a major challenge in clinical. Guided bone regeneration (GBR) is considered one of the most effective methods. However, the efficacy of currently available GBR membranes for repair is frequently limited by their poor osteogenic potential and lack of antibacterial activity. The first step in this investigation was to construct a zinc-based zeolite-imidazolate framework loaded with copper ions (Cu@ZIF-8). Following that, a novel polycaprolactone/polylactic acid/nano-hydroxyapatite/Cu@ZIF-8 (PCL/PLA/n-HA/Cu@ZIF-8) GBR membrane was developed using a simple porogen with nonsolvent-induced phase separation (NIPS) approach. The produced membrane with asymmetric porous structure (one smooth side and one rough side) possesses hydrophilicity corresponding to the roughness of its two sides. The superior mechanical property, stability of degradation, and ion release capability of the membrane all contribute to the clinical feasibility. Additionally, in vitro biological experiments demonstrated that the PCL/PLA/n-HA/Cu@ZIF-8 membrane had favorable osteogenic and antibacterial properties, which suggests the high potential for application in the GBR procedure.


Assuntos
Regeneração Óssea , Durapatita , Durapatita/química , Porosidade , Poliésteres/química , Osteogênese , Antibacterianos/farmacologia
9.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 53(5): 911-915, 2022 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-36224696

RESUMO

Objective: To measure the parameters of eye movement of young adult patients of myopia, to compare the differences in the parameters of patient groups with varied degrees of myopia, and to analyze the correlation between eye movement parameters and axial length (AL) and spherical equivalent refraction (SER). Methods: A total of 91 young adult patients of myopia were recruited. The subjects were divided into three groups of low, moderate, and high myopia according to their SER. Information on the subjects' age and sex was collected and general clinical examination was completed. The subjects' binocular fixation, reflexive saccade, and antisaccade were measured with eye tracker. One-way ANOVA or Kruskal-wallis test was used to compare the general data and eye movement parameters of the three groups of myopic patients. Pearson or Spearman correlation analysis was used to analyze AL and SER's correlation with 95% bivariate contour ellipse area (BCEA) and saccadic parameters. Results: The 95% BCEA for mild, moderate, and high myopia groups were 2.08 (0.54, 14.69) deg 2, 4.99 (0.94, 49.22) deg 2, and 5.79 (2.18, 64.91) deg 2, respectively. There was significant difference between the 95% BCEA of the three groups ( P=0.029). The 95% BCEA of the mild myopia group was significantly smaller than that of the high myopia group ( P=0.01). There were no significant differences in saccadic parameters among the three groups ( P>0.05). There was a significant positive correlation between 95% BCEA and AL ( r=0.342, P=0.001). There was a significant negative correlation between 95% BCEA and SER ( r=-0.322, P=0.002). There was no significant correlation between the parameters of saccadic movement and the AL or SER ( P>0.05). Conclusion: For young adult myopic patients, the longer the AL is, the higher the degree of the myopia and the worse the fixation stability becomes. The fixation stability of patients with high myopia was significantly worse than that of patients with mild myopia. There was no significant difference in saccadic parameters in patients with different degrees of myopia.


Assuntos
Movimentos Oculares , Miopia , Comprimento Axial do Olho , Humanos , Refração Ocular , Adulto Jovem
10.
Zhongguo Zhong Yao Za Zhi ; 47(15): 4156-4163, 2022 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-36046906

RESUMO

Osteoarthritis is a common disease characterized by degenerative lesions of articular cartilage in the elderly.Fufang Duzhong Jiangu Granulues(FDJG), a classical prescription for the treatment of osteoarthritis, has the effects of nourishing liver and kidney, nourishing blood and sinew, and dredging collaterals and relieving pain.In this study, molecular simulation technology was combined with molecular biology methods to explore and verify the potential pharmacodynamic substances and molecular mechanism of FDJG in the treatment of osteoarthritis.Arachidonic acid(AA) metabolic pathway is a typical anti-inflammatory pathway, and secretory phospholipase A2 group ⅡA(sPLA2-ⅡA), 5-lipoxygenase(5-LOX), cyclooxygenase-2(COX-2), and leukotriene A4 hydrolase(LTA4 H) are the key targets of the pathway.Therefore, in this study, based on the pharmacophores and molecular docking models of the four key targets in AA pathway, a total of 1 522 chemical components in 12 medicinals of FDJG were virtually screened, followed by weighted analysis of the screening results in combination with the proportions of the medicinals in the prescription.The results showed that mainly 73 components in the preparation could act on the above four targets, suggesting they might be the potential anti-osteoarthritis components of FDJG.Considering the predicted effectiveness, availability, and compatibility of the medicinals, coniferyl ferulate, olivil, and baicalin were selected for further verification.Specifically, lipopolysaccharide(LPS)-induced RAW264.7 inflammatory cell model was used to verify the anti-inflammatory activity of the three components.The results showed that the three can effectively inhibit the release of NO, supporting the above selection.In addition, targets 5-LOX, COX-2, and LTA4 H had high activity, which suggested that they may be the key anti-osteoarthritis targets of FDJG.The comprehensive activity values of Eucommiae Cortex, Achyranthis Bidentatae Radix, Ginseng Radix et Rhizoma, Lycii Fructus, and Astragali Radix were much higher than that of other medicinals in the prescription, indicating that they may be the main effective medicinals in FDJG acting on the AA pathway.In this study, the potential anti-osteoarthritis components of FDJG were obtained.Moreover, it was clarified that the anti-osteoarthritis mechanism of FDJG was to act on LOX and COX pathway in AA metabolic pathway, which provided a reference for the study of pharmacodynamic substances and molecular mechanism of FDJG.


Assuntos
Medicamentos de Ervas Chinesas , Osteoartrite , Idoso , Anti-Inflamatórios/uso terapêutico , Ciclo-Oxigenase 2/metabolismo , Medicamentos de Ervas Chinesas/uso terapêutico , Humanos , Leucotrieno A4/análise , Lipopolissacarídeos , Simulação de Acoplamento Molecular , Osteoartrite/tratamento farmacológico , Rizoma/química
11.
Biotechnol Lett ; 44(8): 951-960, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35771408

RESUMO

OBJECTIVES: Ovarian cancer is one of the most fatal gynecological malignancies. It is emergently needed to select a novel molecular fragment as a targeting element for the future development of molecular imaging diagnosis and targeting chemotherapy to ovarian cancer. RESULTS: After five rounds of biopanning, a total of 44 positive phage clones were selected from final phage displayed peptide library. Nine consensus sequences were found based on the assay of sequencing results, then one clone of each consensus group was characterized and identified further by immunofluorescence assay. The result showed the phage clone R20 presents best targeting capacity. Then we synthesized peptide (OSP2) clone R20 displayed, it was characterized with high specificity and sensitivity binding to human ovarian cancer by a tissue chip assay. The target of OSP2 was predicted and docked as human carbonic anhydrase XII (CA12), an important protein usually deregulated in cancer. CONCLUSIONS: Taken together, OSP2 and its target indicate a novel investigation way in future to develop novel agent or drug delivery formulation for molecular imaging diagnosis and targeting chemotherapy of ovarian cancer.


Assuntos
Bacteriófagos , Neoplasias Ovarianas , Bacteriófagos/metabolismo , Linhagem Celular Tumoral , Feminino , Humanos , Biblioteca de Peptídeos , Peptídeos/química , Ligação Proteica
12.
J Parkinsons Dis ; 12(5): 1463-1478, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35527562

RESUMO

BACKGROUND: Parkinson's disease involves aberrant aggregation of the synaptic protein alpha-synuclein (aSyn) in the nigrostriatal tract. We have previously shown that proSAAS, a small neuronal chaperone, blocks aSyn-induced dopaminergic cytotoxicity in primary nigral cultures. OBJECTIVE: To determine if proSAAS overexpression is neuroprotective in animal models of Parkinson's disease. METHODS: proSAAS- or GFP-encoding lentivirus was injected together with human aSyn-expressing AAV unilaterally into the substantia nigra of rats and motor asymmetry assessed using a battery of motor performance tests. Dopamine neuron survival was assessed by nigral stereology and striatal tyrosine hydroxylase (TH) densitometry. To examine transsynaptic spread of aSyn, aSyn AAV was injected into the vagus of mice in the presence of AAVs encoding either GFP or proSAAS; the spread of aSyn-positive neurites into rostral nuclei was quantified following immunohistochemistry. RESULTS: Coinjection of proSAAS-encoding lentivirus profoundly reduced the motor asymmetry caused by unilateral nigral AAV-mediated human aSyn overexpression. This was accompanied by significant amelioration of the human aSyn-induced loss of both nigral TH-positive cells and striatal TH-positive terminals, demonstrating clear proSAAS-mediated protection of the nigrostriatal tract. ProSAAS overexpression reduced human aSyn protein levels in nigra and striatum and reduced the loss of TH protein in both regions. Following vagal administration of human aSyn-encoding AAV, the number of human aSyn-positive neurites in the pons and caudal midbrain was considerably reduced in mice coinjected with proSAAS-, but not GFP-encoding AAV, supporting proSAAS-mediated blockade of transsynaptic aSyn transmission. CONCLUSION: The proSAAS chaperone may represent a promising target for therapeutic development in Parkinson's disease.


Assuntos
Doença de Parkinson , alfa-Sinucleína , Animais , Modelos Animais de Doenças , Dopamina/metabolismo , Neurônios Dopaminérgicos/metabolismo , Camundongos , Neuroproteção , Doença de Parkinson/terapia , Ratos , Roedores/metabolismo , Substância Negra/metabolismo , Tirosina 3-Mono-Oxigenase/metabolismo , alfa-Sinucleína/metabolismo
13.
Eur J Pharmacol ; 923: 174933, 2022 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-35367421

RESUMO

Human retinal microvascular endothelial cells (HRMECs) injury plays an essential role in the pathogenesis of diabetic retinopathy (DR). As one of the crucial pathogenetic factors, oxidative stress induces HRMECs apoptosis and microvascular lesions. Nuclear factor erythroid 2-related factor 2 (Nrf2) acts as a molecular switch in oxidative stress-induced HRMECs injury. The present study was designed to investigate the protective effect and underlying mechanism of carnosol, a potential Nrf2 agonist, in tert-butyl hydroperoxide (t-BHP) induced HRMECs oxidative stress injury. In this study, carnosol was found to inhibit HRMECs injury induced by t-BHP. Transcriptomics and molecular biology illustrated that the mechanism was associated with oxidative stress, vascular system development, apoptosis, cell cycle, cell adhesion, cytoskeleton, and nitric oxide biosynthesis. Carnosol directly scavenged free radicals or activated the Nrf2 signaling pathway to alleviate HRMECs oxidative stress. ML385 pretreatment or Nrf2 small interference RNA (siRNA) inhibited the protective effect of carnosol on HRMECs injury. Moreover, the apoptosis and cell cycle arrest in HRMECs were suppressed by carnosol. Treatment with carnosol could also effectively regulate the adhesion and cytoskeleton. Overall, our data provide a systematic perspective for the mechanism of carnosol against HRMECs oxidative stress injury and reveal that carnosol may be a candidate drug for DR therapy.


Assuntos
Retinopatia Diabética , Doenças Retinianas , Abietanos , Células Endoteliais , Humanos , Biologia Molecular , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Transcriptoma , terc-Butil Hidroperóxido/toxicidade
14.
Biochem Biophys Res Commun ; 603: 138-143, 2022 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-35287055

RESUMO

Schistosoma japonicum is a parasitic worm that lives in the mesenteric vein of its host and feeds on blood, suggesting that it might be a natural resource of novel anticoagulants. Here, by comprehensive analyses of the genomic sequences of Schistosoma japonicum, a new Kunitz-type gene precursor was identified. The Kunitz-type gene precursor codes for an 18-residue signal peptide and a 60-residue mature peptide. The Kunitz peptide was functionally expressed, and it had apparent inhibitory activity towards the intrinsic coagulation pathway but no effect on the extrinsic coagulation pathway even at the high concentration of 3 µM. Enzyme and inhibitor experiments further showed that the Kunitz domain peptide was a potent and selective FXa inhibitor, so it was named Schixator (Schistosoma FXa inhibitor). Schixator inhibits coagulation factor FXa with a Ki of 2.66 nM, but had weak inhibitory activity towards chymotrypsin, FXIa, plasma kallikrein, and plasmin, and no inhibitory activity towards trypsin, elastase, FIIa or FXIIa. In vivo, the intravenous administration of Schixator into mice dramatically decreased the number of thrombi in the carotid artery in an FeCl3-induced thrombus formation model without producing bleeding complications. To the best of our knowledge, Schixator is the first potent and selective FXa inhibitor from parasitic worms with antithrombotic effects and a low bleeding risk that provides a new clue for lead drug discovery against thrombosis-associated human diseases.


Assuntos
Schistosoma japonicum , Trombose , Animais , Anticoagulantes/farmacologia , Coagulação Sanguínea , Inibidores do Fator Xa/farmacologia , Fibrinolíticos/farmacologia , Fibrinolíticos/uso terapêutico , Hemorragia , Camundongos , Trombose/tratamento farmacológico
15.
IEEE Trans Neural Netw Learn Syst ; 33(12): 7534-7544, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34138717

RESUMO

This article investigates the nonnegative consensus tracking problem for networked systems with a distributed static output-feedback (SOF) control protocol. The distributed SOF controller design for networked systems presents a more challenging issue compared with the distributed state-feedback controller design. The agents are described by multi-input multi-output (MIMO) positive dynamic systems which may contain uncertain parameters, and the interconnection among the followers is modeled using an undirected connected communication graph. By employing positive systems theory, a series of necessary and sufficient conditions governing the consensus of the nominal, as well as uncertain, networked positive systems, is developed. Semidefinite programming consensus design approaches are proposed for the convergence rate optimization of MIMO agents. In addition, by exploiting the positivity characteristic of the systems, a linear-programming-based design approach is also proposed for the convergence rate optimization of single-input multi-output (SIMO) agents. The proposed approaches and the corresponding theoretical results are validated by case studies.

16.
IEEE Trans Cybern ; 52(11): 11649-11660, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34029203

RESUMO

This work focuses on the stability analysis of positive Takagi-Sugeno (T-S) fuzzy descriptor systems with time-varying delays. An equivalent augmented system is constructed to investigate the positivity and stability of T-S fuzzy descriptor time-delay systems. By using this transformed system, a necessary and sufficient positivity condition is first derived for systems, which can be verified by linear programming (LP). Then, based on the positivity of T-S fuzzy descriptor systems, a sufficient condition is put forward for the asymptotic stability of systems with bounded and unbounded time-varying delays. Finally, several examples are provided to show the effectiveness of the obtained results.


Assuntos
Algoritmos , Lógica Fuzzy
18.
Int J Mol Sci ; 22(19)2021 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-34639214

RESUMO

Lymphoid enhancer-binding factor 1 (LEF1) is a key transcription factor mediating the Wnt signaling pathway. LEF1 is a regulator that is closely associated with tumor malignancy and is usually upregulated in cancers, including colonic adenocarcinoma. The underlying molecular mechanisms of LEF1 regulation for colonic adenocarcinoma progression remain unknown. To explore it, the LEF1 expression in caco2 cells was inhibited using an shRNA approach. The results showed that downregulation of LEF1 inhibited the malignancy and motility associated microstructures, such as polymerization of F-actin, ß-tubulin, and Lamin B1 in caco2 cells. LEF1 inhibition suppressed the expression of epithelial/endothelial-mesenchymal transition (EMT) relevant genes. Overall, the current results demonstrated that LEF1 plays a pivotal role in maintaining the malignancy of colonic adenocarcinoma by remodeling motility correlated microstructures and suppressing the expression of EMT-relevant genes. Our study provided evidence of the roles LEF1 played in colonic adenocarcinoma progression, and suggest LEF1 as a potential target for colonic adenocarcinoma therapy.


Assuntos
Adenocarcinoma/patologia , Biomarcadores Tumorais/metabolismo , Movimento Celular , Neoplasias do Colo/patologia , Regulação Neoplásica da Expressão Gênica , Fator 1 de Ligação ao Facilitador Linfoide/metabolismo , Actinas/metabolismo , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Apoptose , Biomarcadores Tumorais/genética , Proliferação de Células , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Humanos , Fator 1 de Ligação ao Facilitador Linfoide/genética , Pseudópodes/metabolismo , Tubulina (Proteína)/metabolismo , Células Tumorais Cultivadas
19.
Zhongguo Zhong Yao Za Zhi ; 46(18): 4824-4832, 2021 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-34581094

RESUMO

As one of the most commonly diagnosed cancers in the world, female breast cancer is induced by the high level of estrogen. Saussureae Involucratae Herba(SIH), a gynecological medicinal, regulates estrogen-induced diseases. However, the therapeutic effect of SIH on breast cancer has not been reported. Therefore, this study aims to explore the potential efficacy of SIH on breast cancer based on in vitro experiment and network pharmacology. The inhibitory effect of SIH water extract on proliferation and migration of breast cancer MDA-MB-231 cells was examined. The result demonstrated SIH water extract significantly suppressed the proliferation of breast cancer cells(IC_(50)=6.47 mg·mL~(-1)) and also restricted the migration. A total of 39 components of SIH were retrieved from traditional Chinese medicine database(TCMD) and 160 targets of SIH were screened by target fishing with the PharmaDB database. The Online Mendelian Inheritance in Man(OMIM) was used to establish a 1 001-targets data set of breast cancer. Based on the overlaps(45) of targets between SIH and breast cancer, a protein-protein interaction(PPI) network was built to analyze the interactions among these targets with STRING platform and Cytoscape. Finally, through topology and GO and KEGG analysis, 8 targets, 101 pathways and 85 biological processes were found to involve the treatment of breast cancer by SIH. SIH may exert the anti-breast cancer effect by regulating cell cycle, inhibiting proliferation, migration and adhesion of cancer cells, and modulating estrogen receptor. This study clarified the mechanism of SIH in treating breast cancer, which lays a foundation for the further development of SIH.


Assuntos
Neoplasias da Mama , Medicamentos de Ervas Chinesas , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Bases de Dados Genéticas , Feminino , Humanos , Medicina Tradicional Chinesa
20.
Front Microbiol ; 12: 684591, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34335511

RESUMO

Antibiotic-resistant ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species) has become a serious threat to public health worldwide. Cationic α-helical antimicrobial peptides (CαAMPs) have attracted much attention as promising solutions in post-antibiotic era. However, strong hemolytic activity and in vivo inefficacy have hindered their pharmaceutical development. Here, we attempt to address these obstacles by investigating BmKn2 and BmKn2-7, two scorpion-derived CαAMPs with the same hydrophobic face and a distinct hydrophilic face. Through structural comparison, mutant design and functional analyses, we found that while keeping the hydrophobic face unchanged, increasing the number of alkaline residues (i.e., Lys + Arg residues) on the hydrophilic face of BmKn2 reduces the hemolytic activity and broadens the antimicrobial spectrum. Strikingly, when keeping the total number of alkaline residues constant, increasing the number of Lys residues on the hydrophilic face of BmKn2-7 significantly reduces the hemolytic activity but does not influence the antimicrobial activity. BmKn2-7K, a mutant of BmKn2-7 in which all of the Arg residues on the hydrophilic face were replaced with Lys, showed the lowest hemolytic activity and potent antimicrobial activity against antibiotic-resistant ESKAPE pathogens. Moreover, in vivo experiments indicate that BmKn2-7K displays potent antimicrobial efficacy against both the penicillin-resistant S. aureus and the carbapenem- and multidrug-resistant A. baumannii, and is non-toxic at the antimicrobial dosages. Taken together, our work highlights the significant functional disparity of Lys vs Arg in the scorpion-derived antimicrobial peptide BmKn2-7, and provides a promising lead molecule for drug development against ESKAPE pathogens.

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