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1.
Diabetes Metab Syndr ; 18(5): 103042, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38781718

RESUMO

AIMS: The clinical utility of waist-to-height ratio (WHtR) in predicting cardiometabolic risk factors (CMRFs) and subclinical markers of cardiovascular disease remains controversial. We aimed to compare the utility of WHtR with waist circumference (WC) and body mass index (BMI) in identifying children and adolescents (youths) at risk for cardiometabolic outcomes, including clustered CMRFs, high carotid intima-media thickness (cIMT), and arterial stiffness (assessed as high pulse wave velocity, PWV). METHODS: We analyzed data from 34,224 youths (51.0 % boys, aged 6-18 years) with CMRFs, 5004 (49.5 % boys, aged 6-18 years) with cIMT measurement, and 3100 (56.4 % boys, aged 6-17 years) with PWV measurement from 20 pediatric samples across 14 countries. RESULTS: WHtR, WC, and BMI z-scores had similar performance in discriminating youths with ≥3 CMRFs, with the area under the curve (AUC) (95 % confidence interval, CI)) ranging from 0.77 (0.75-0.78) to 0.78 (0.76-0.80) using the modified National Cholesterol Education Program (NCEP) definition, and from 0.77 (0.74-0.79) to 0.77 (0.74-0.80) using the International Diabetes Federation (IDF) definition. Similarly, all three measures showed similar performance in discriminating youths with subclinical vascular outcomes, with AUC (95 % CI) ranging from 0.67 (0.64-0.71) to 0.70 (0.66-0.73) for high cIMT (≥P95 values) and from 0.60 (0.58-0.66) to 0.62 (0.58-0.66) for high PWV (≥P95 values). CONCLUSIONS: Our findings suggest that WHtR, WC, and BMI are equally effective in identifying at-risk youths across diverse pediatric populations worldwide. Given its simplicity and ease of use, WHtR could be a preferable option for quickly screening youths with increased cardiometabolic risk in clinical settings.

2.
World J Clin Cases ; 12(9): 1622-1633, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38576744

RESUMO

BACKGROUND: The pathogenesis of ulcerative colitis (UC) is complex, and recent therapeutic advances remain unable to fully alleviate the condition. AIM: To inform the development of novel UC treatments, bioinformatics was used to explore the autophagy-related pathogenesis associated with the active phase of UC. METHODS: The GEO database was searched for UC-related datasets that included healthy controls who met the screening criteria. Differential analysis was conducted to obtain differentially expressed genes (DEGs). Autophagy-related targets were collected and intersected with the DEGs to identiy differentially expressed autophagy-related genes (DEARGs) associated with active UC. DEARGs were then subjected to KEGG, GO, and DisGeNET disease enrichment analyses using R software. Differential analysis of immune infiltrating cells was performed using the CiberSort algorithm. The least absolute shrinkage and selection operator algorithm and protein-protein interaction network were used to narrow down the DEARGs, and the top five targets in the Dgree ranking were designated as core targets. RESULTS: A total of 4822 DEGs were obtained, of which 58 were classified as DEARGs. SERPINA1, BAG3, HSPA5, CASP1, and CX3CL1 were identified as core targets. GO enrichment analysis revealed that DEARGs were primarily enriched in processes related to autophagy regulation and macroautophagy. KEGG enrichment analysis showed that DEARGs were predominantly associated with NOD-like receptor signaling and other signaling pathways. Disease enrichment analysis indicated that DEARGs were significantly linked to diseases such as malignant glioma and middle cerebral artery occlusion. Immune infiltration analysis demonstrated a higher presence of immune cells like activated memory CD4 T cells and follicular helper T cells in active UC patients than in healthy controls. CONCLUSION: Autophagy is closely related to the active phase of UC and the potential targets obtained from the analysis in this study may provide new insight into the treatment of active UC patients.

3.
Front Aging Neurosci ; 16: 1267780, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38352237

RESUMO

Background: Alzheimer's disease (AD) is characterized by neuroinflammation, which is frequently accompanied by immune system dysfunction. Although the mechanism of neurodegenerative lesions is unclear, various clinical trials have highlighted that early intervention in AD is crucial to the success of treatment. In order to explore the potential of immunotherapy in the early period of AD, the present study evaluated whether application of glatiramer acetate (GA), an immunomodulatory agent approved for remitting-relapsing multiple sclerosis (RRMS), in the early stages of AD prior to amyloid beta (Aß) deposition altered the Aß pathology and cognitive impairments in APPswe/PSEN1dE9 (APP/PS1) transgenic mice. Methods: We treated two cohorts of pre-depositing and amyloid-depositing (2- and 6-month-old) APP/PS1 mice with weekly-GA subcutaneous injection over a 12-week period. We then tested spatial learning and memory using the Morris water maze (MWM) and the Y maze. Immunohistochemistry staining was utilized to analyze Aß burden in the brain as well as activated microglia. Furthermore, the inflammatory cytokine milieu within brains was estimated by quantitative real-time polymerase chain reaction, and the peripheral CD4+CD25+Foxp3+ regulatory T cells (Tregs) in the spleen were measured by flow cytometry. Results: We found that early GA administration reduced Aß burden and ameliorated cognitive decline. Meanwhile, the immune microenvironment had changed in the brain, with an increase in the production of anti-inflammatory cytokines and a decrease in microglial activation. Interestingly, early GA administration also modulated the peripheral immune system through the amplification of Tregs in the spleen. Conclusion: Overall, our findings revealed that GA treatment might enhance the central and peripheral immune systems' protective capabilities in the early stages of AD, eventually improving cognitive deficits. Our research supports the advantages of immunomodulatory treatments for AD at an early stage.

4.
Neurosci Lett ; 818: 137555, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37972684

RESUMO

The massive cell death of dopaminergic neurons (DANs) in substantia nigra pars compacta (SNC) is associated with motor diseases, such as Parkinson's disease. Moreover, as a subtype of DANs in SNC, ALDH1A1+ neurons show better resistance to PD related neurotoxin. DANs can also be found in the substantia nigra pars reticulata (SNR), however, whether they are ALDH1A1+ neurons are rarely reported, as well as their projection, function, and reaction in the PD pathology. We studied the distribution of ALDH1A1+ neurons and track their projection by injecting pAAV. We figured out that, in SNR, 87 % neurons are ALDH1A1+/TH+ in ALDH1A1+ cluster averagely, while ALDH1A1+/TH+: TH+ is 52 % averagely. There are two enrichment regions of ALDH1A1+/TH+ neurons at brgma -3.40 mm and brgma -3.70 mm in the SNR of the nTg mice. Nevertheless, in one type of PD-liked mice model, the proportion of ALDH1A1+/TH+: ALDH1A1+ neurons are 98 % averagely, while ALHD1A1+/TH+: TH+ is 57 %. Intriguingly, neuro-tracing discovered that there may be a previously unreported connection between SNR and anterior dorsal thalamus (ADT). The mouse received MPTP stereotactic injection to destroy TH+ neurons in SNR showed depression behavior, indicated the DANs death in SNR may contribute to depression behavior.


Assuntos
Doença de Parkinson , Parte Reticular da Substância Negra , Camundongos , Animais , Substância Negra/metabolismo , Doença de Parkinson/metabolismo , Parte Compacta da Substância Negra , Neurônios Dopaminérgicos
5.
Animals (Basel) ; 13(20)2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37893966

RESUMO

In order to achieve goat localization to help prevent goats from wandering, we proposed an efficient target localization method based on machine vision. Albas velvet goats from a farm in Ertok Banner, Ordos City, Inner Mongolia Autonomous Region, China, were the main objects of study. First, we proposed detecting the goats using a shallow convolutional neural network, ShallowSE, with the channel attention mechanism SENet, the GeLU activation function and layer normalization. Second, we designed three fully connected coordinate regression network models to predict the spatial coordinates of the goats. Finally, the target detection algorithm and the coordinate regression algorithm were combined to localize the flock. We experimentally confirmed the proposed method using our dataset. The proposed algorithm obtained a good detection accuracy and successful localization rate compared to other popular algorithms. The overall number of parameters in the target detection algorithm model was only 4.5 M. The average detection accuracy reached 95.89% and the detection time was only 8.5 ms. The average localization error of the group localization algorithm was only 0.94 m and the localization time was 0.21 s. In conclusion, the method achieved fast and accurate localization, which helped to rationalize the use of grassland resources and to promote the sustainable development of rangelands.

6.
Stem Cells ; 40(1): 59-73, 2022 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-35511865

RESUMO

Increased neurogenesis elicits antidepressive-like effects. The antidiabetic drug metformin (Met) reportedly promotes hippocampal neurogenesis, which ameliorates spatial memory deficits and depression-like behaviors. However, the precise molecular mechanisms underpinning Met-induced neuronal differentiation of neural stem cells (NSCs) remain unclear. We showed that Met enhanced neuronal differentiation of NSCs via Gadd45g but not Gadd45a and Gadd45b. We further found that Gadd45g increased demethylation of neurogenic differentiation 1 promoter by regulating the activity of passive and active DNA demethylation enzymes through an adenylate-activated protein kinase -independent mechanism in Met-treated NSCs. Importantly, genetic deficiency of Gadd45g decreased hippocampal neurogenesis, which could contribute to spatial memory decline, and depression-like behaviors in the adult mice, whereas forced expression of Gadd45g alleviated the depressive-like behaviors. Our findings provide a model that Gadd45g-mediated DNA demethylation contributes to Met-induced neuronal genesis and its antidepressant-like effects and propose the concept that targeting Gadd45g regulation of neurogenesis might serve as a novel antidepressant strategy.


Assuntos
Metformina , Células-Tronco Neurais , Animais , Antidepressivos/metabolismo , Antidepressivos/farmacologia , Antígenos de Diferenciação/genética , Antígenos de Diferenciação/metabolismo , Desmetilação do DNA , Hipocampo/metabolismo , Metformina/metabolismo , Metformina/farmacologia , Camundongos , Células-Tronco Neurais/metabolismo , Neurogênese
7.
BMC Bioinformatics ; 21(1): 566, 2020 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-33297947

RESUMO

BACKGROUND: Drug repositioning has been an important and efficient method for discovering new uses of known drugs. Researchers have been limited to one certain type of collaborative filtering (CF) models for drug repositioning, like the neighborhood based approaches which are good at mining the local information contained in few strong drug-disease associations, or the latent factor based models which are effectively capture the global information shared by a majority of drug-disease associations. Few researchers have combined these two types of CF models to derive a hybrid model which can offer the advantages of both. Besides, the cold start problem has always been a major challenge in the field of computational drug repositioning, which restricts the inference ability of relevant models. RESULTS: Inspired by the memory network, we propose the hybrid attentional memory network (HAMN) model, a deep architecture combining two classes of CF models in a nonlinear manner. First, the memory unit and the attention mechanism are combined to generate a neighborhood contribution representation to capture the local structure of few strong drug-disease associations. Then a variant version of the autoencoder is used to extract the latent factor of drugs and diseases to capture the overall information shared by a majority of drug-disease associations. During this process, ancillary information of drugs and diseases can help alleviate the cold start problem. Finally, in the prediction stage, the neighborhood contribution representation is coupled with the drug latent factor and disease latent factor to produce predicted values. Comprehensive experimental results on two data sets demonstrate that our proposed HAMN model outperforms other comparison models based on the AUC, AUPR and HR indicators. CONCLUSIONS: Through the performance on two drug repositioning data sets, we believe that the HAMN model proposes a new solution to improve the prediction accuracy of drug-disease associations and give pharmaceutical personnel a new perspective to develop new drugs.


Assuntos
Algoritmos , Biologia Computacional/métodos , Reposicionamento de Medicamentos , Bases de Dados como Assunto , Humanos , Estatística como Assunto
8.
Ann Plast Surg ; 85(4): 430-436, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32931683

RESUMO

PURPOSE: This study aimed to investigate the repair of bone defects in rabbits with tissue-engineered bones using cocultured endothelial progenitor cells (EPCs) and bone marrow mesenchymal stem cells (BMSCs) as seeding cells. METHODS: Endothelial progenitor cells and BMSCs were isolated and purified from the peripheral blood and bone marrow, respectively, of New Zealand rabbits. The third passage of BMSCs was cultured alone or with EPCs. Cells were characterized using specific markers and then seeded on partially deproteinized biologic bones from pigs as a scaffold. The engineered bones were used to repair bone defects in rabbits. Hematoxylin and eosin and Masson staining were performed to examine vascularization and osteogenesis in the engineered bone. RESULTS: The cocultured EPCs and BMSCs grew well on the surface of the scaffold. Compared with monocultured BMSCs, cocultured EPCs and BMSCs promoted the formation of blood vessels and bone on the scaffold, in addition to accelerating the repair of bone defects. The collagen content was significantly increased in the scaffold with cocultured EPCs and BMSCs, compared with the scaffold seeded with mono-cultured BMSCs. CONCLUSIONS: Tissue-engineered bones seeded with cocultured EPCs and BMSCs may be used effectively for the repair of bone defects.


Assuntos
Medula Óssea , Células Progenitoras Endoteliais , Células-Tronco Mesenquimais , Engenharia Tecidual , Animais , Células da Medula Óssea , Células Cultivadas , Osteogênese , Coelhos , Suínos , Alicerces Teciduais
9.
Neuroscience ; 448: 94-106, 2020 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-32946950

RESUMO

Neuroinflammation contributes to neuronal death in cerebral ischemia. Urolithin A (UA), a gut microbial metabolite of ellagic acid, has emerged as a potential anti-inflammatory agent. However, its roles and precise mechanisms in stroke remain unknown. Here we found that UA treatment ameliorated infarction, neurological deficit scores, and spatial memory deficits after cerebral ischemia. Furthermore, UA significantly reduced neuron loss and promoted neurogenesis after ischemic stroke. We also found that UA attenuated apoptosis by regulating apoptotic-related proteins. Meanwhile, UA treatment inhibited glial activation via affecting inflammatory signaling pathways, specifically by enhancing cerebral AMPK and IκBa activation while decreasing the activation of Akt, P65NFκB, ERK, JNK, and P38MAPK. Our findings reveal a key role of UA against ischemic stroke through modulating apoptosis and neuroinflammation in mice.


Assuntos
Isquemia Encefálica , Acidente Vascular Cerebral , Animais , Apoptose , Isquemia Encefálica/tratamento farmacológico , Cumarínicos/farmacologia , Camundongos , Transdução de Sinais , Acidente Vascular Cerebral/tratamento farmacológico
10.
J Neuroinflammation ; 16(1): 62, 2019 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-30871577

RESUMO

BACKGROUND: Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by an abnormal accumulation of amyloid-ß (Aß) plaques, neuroinflammation, and impaired neurogenesis. Urolithin A (UA), a gut-microbial metabolite of ellagic acid, has been reported to exert anti-inflammatory effects in the brain. However, it is unknown whether UA exerts its properties of anti-inflammation and neuronal protection in the APPswe/PS1ΔE9 (APP/PS1) mouse model of AD. METHODS: Morris water maze was used to detect the cognitive function. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay was performed to detect neuronal apoptosis. Immunohistochemistry analyzed the response of glia, Aß deposition, and neurogenesis. The expression of inflammatory mediators were measured by enzyme-linked immunosorbent assay (ELISA) and quantitative real-time polymerase chain reaction (qRT-PCR). The modulating effects of UA on cell signaling pathways were assayed by Western blotting. RESULTS: We demonstrated that UA ameliorated cognitive impairment, prevented neuronal apoptosis, and enhanced neurogenesis in APP/PS1 mice. Furthermore, UA attenuated Aß deposition and peri-plaque microgliosis and astrocytosis in the cortex and hippocampus. We also found that UA affected critical cell signaling pathways, specifically by enhancing cerebral AMPK activation, decreasing the activation of P65NF-κB and P38MAPK, and suppressing Bace1 and APP degradation. CONCLUSIONS: Our results indicated that UA imparted cognitive protection by protecting neurons from death and triggering neurogenesis via anti-inflammatory signaling in APP/PS1 mice, suggesting that UA might be a promising therapeutic drug to treat AD.


Assuntos
Anti-Inflamatórios/uso terapêutico , Cumarínicos/uso terapêutico , Citocinas/metabolismo , Encefalite/tratamento farmacológico , Regulação da Expressão Gênica/efeitos dos fármacos , Transtornos da Memória/tratamento farmacológico , Doença de Alzheimer/complicações , Doença de Alzheimer/genética , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Citocinas/genética , Modelos Animais de Doenças , Encefalite/etiologia , Feminino , Regulação da Expressão Gênica/genética , Gliose/tratamento farmacológico , Gliose/genética , Aprendizagem em Labirinto/efeitos dos fármacos , Transtornos da Memória/etiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteínas do Tecido Nervoso/metabolismo , Neurogênese/efeitos dos fármacos , Neurogênese/genética , Placa Amiloide/tratamento farmacológico , Placa Amiloide/etiologia , Presenilina-1/genética , Presenilina-1/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética
11.
Brain Behav Immun ; 79: 159-173, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30763768

RESUMO

Neuroinflammation, considered as a pathological hallmark of Alzheimer's disease (AD), has been demonstrated to affect hippocampal neurogenesis and cognitive function. Interleukin-6 (IL-6) is a proinflammatory cytokine known to modulate neurogenesis. However, the mechanisms are still largely unknown. Here, we reported that IL-6 suppressed neurogenesis via a JAK2/STAT3 signaling in neural stem cells (NSCs). Importantly, we found that NeuroD1 (Neurogenic differentiation 1) gene expression, which drives NSCs neurodifferentiation, was regulated by TET3 and DNMT1 in a JAK2/STAT3-dependent manner. We further found that JAK2/STAT3 inhibition enhanced demethylation of NeuroD1 regulatory elements in IL-6-treated cells, which is related to the significant upregulation of TET3 expression as well as the decreased expression of DNMT1. Furthermore, Inhibiting JAK2/STAT3 significantly rescued the memory deficits and hippocampal neurogenesis dysfunction in APP/PS1 mice. Our data suggest that JAK2/STAT3 signaling plays a vital role in suppressing neurogenesis of NSCs exposed to IL-6 at the epigenetic level, by regulating DNA methylation/demethylation.


Assuntos
Janus Quinase 2/metabolismo , Neurogênese/fisiologia , Fator de Transcrição STAT3/metabolismo , Doença de Alzheimer/metabolismo , Doença de Alzheimer/fisiopatologia , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , DNA (Citosina-5-)-Metiltransferase 1/genética , DNA (Citosina-5-)-Metiltransferase 1/metabolismo , Desmetilação do DNA , Metilação de DNA , Dioxigenases/genética , Dioxigenases/metabolismo , Hipocampo/metabolismo , Humanos , Interleucina-6/metabolismo , Masculino , Camundongos , Camundongos Transgênicos , Células-Tronco Neurais/metabolismo , Neurogênese/imunologia , Neuroimunomodulação , Transdução de Sinais/imunologia
12.
Brain Behav Immun ; 69: 351-363, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29253574

RESUMO

Alzheimer'sdisease(AD) is characterized by deposition of amyloid-ß (Aß)plaques, neurofibrillary tangles, andneuronal loss, accompaniedbyneuroinflammation. Neuroinflammatoryprocesses are thought to contribute toAD pathophysiology. Metformin has been reported to have anti-inflammatory efficacy. However, whether metformin is responsible for the anti-neuroinflammationand neuroprotection on APPswe/PS1ΔE9 (APP/PS1) mice remains unclear. Here we showed that metformin attenuated spatial memory deficit, neuron loss in the hippocampus and enhanced neurogenesis in APP/PS1 mice. In addition, metformin administration decreased amyloid-ß (Aß)plaque load and chronic inflammation (activated microglia and astrocytes as well as pro-inflammatory mediators) in the hippocampus and cortex. Further study demonstrated that treatment with metformin enhanced cerebral AMPK activation. Meanwhile, metformin notably suppressed the activation of P65 NF-κB, mTOR and S6K, reduced Bace1 protein expression. Our data suggest that metformin can exert functional recovery of memory deficits and neuroprotective effect on APP/PS1 mice via triggering neurogenesis and anti-inflammation mediated by regulating AMPK/mTOR/S6K/Bace1 and AMPK/P65 NF-κB signaling pathways in the hippocampus, which may contribute to improvement in neurological deficits.


Assuntos
Doença de Alzheimer/patologia , Hipocampo/efeitos dos fármacos , Transtornos da Memória/prevenção & controle , Metformina/uso terapêutico , Fármacos Neuroprotetores/uso terapêutico , Placa Amiloide/prevenção & controle , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Hipocampo/metabolismo , Hipocampo/patologia , Masculino , Transtornos da Memória/metabolismo , Transtornos da Memória/patologia , Metformina/farmacologia , Camundongos , Camundongos Transgênicos , Fármacos Neuroprotetores/farmacologia , Placa Amiloide/metabolismo , Placa Amiloide/patologia , Presenilina-1/genética , Presenilina-1/metabolismo
13.
Stem Cell Reports ; 8(5): 1256-1269, 2017 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-28494938

RESUMO

Although valproic acid (VPA), has been shown to induce neuronal differentiation of neural stem cells (NSCs), the underlying mechanisms remain poorly understood. Here we investigated if and how mammalian target of rapamycin (mTOR) signaling is involved in the neuronal differentiation of VPA-induced NSCs. Our data demonstrated that mTOR activation not only promoted but also was necessary for the neuronal differentiation of NSCs induced by VPA. We further found that inhibition of mTOR signaling blocked demethylation of neuron-specific gene neurogenin 1 (Ngn1) regulatory element in induced cells. These are correlated with the significant alterations of passive DNA demethylation and the active DNA demethylation pathway in the Ngn1 promoter, but not the suppression of lysine-specific histone methylation and acetylation in the promoter region of Ngn1. These findings highlight a potentially important role for mTOR signaling, by working together with DNA demethylation, to influence the fate of NSCs via regulating the expression of Ngn1 in VPA-induced neuronal differentiation of NSCs.


Assuntos
Epigênese Genética , Células-Tronco Neurais/metabolismo , Neurogênese , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Células Cultivadas , Metilação de DNA , Inibidores Enzimáticos/farmacologia , Código das Histonas , Proteínas do Tecido Nervoso/metabolismo , Células-Tronco Neurais/citologia , Células-Tronco Neurais/efeitos dos fármacos , Regiões Promotoras Genéticas , Ratos , Ratos Sprague-Dawley , Ácido Valproico/farmacologia
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