Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 15 de 15
Filtrar
1.
J Org Chem ; 86(12): 8437-8447, 2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34042441

RESUMO

An efficient transition-metal-free decarboxylative cyclization of N-arylacrylamides with 2,2-difluoro-2-(phenylthio)acetic acid for the construction of thiodifluoroindoleone derivatives is described. This strategy features stable and readily available substrates, mild reaction conditions, and transition-metal-free catalysts. Notably, this protocol has successfully applied to synthesis of gem-difluoroalkenes, which exist in numerous biologically active compounds.

2.
Gynecol Obstet Invest ; 86(3): 264-272, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34139701

RESUMO

OBJECTIVES: The pathogenesis of preeclampsia (PE) is associated with impaired trophoblast invasion, which results in placental insufficiency. Our earlier studies demonstrated that tissue transglutaminase (tTG) is highly expressed in human PE serum. However, whether tTG participates in trophoblast invasion remains unclear. The aim of the present study was to determine the role and mechanism of tTG in regulating matrix metalloproteinase (MMP)-2/MMP-9 expression to reduce trophoblast invasiveness in PE. METHODS: HTR-8/SVneo cells were transfected with a lentivirus vector and small interfering RNA targeting tTG. The protein level was detected by Western blotting. Cell proliferation and apoptosis were assessed by MTS and flow cytometry assays, respectively. Cell invasion was investigated by Transwell assay. In addition, the influence of tTG on PI3K and AKT mRNA levels in HTR-8/SVneo cells was evaluated using reverse transcription-quantitative PCR. RESULTS: tTG-overexpression inhibited HTR-8/SVneo cell proliferation and invasion and promoted apoptosis. In addition, upregulation of tTG induced an increase of PI3K and phosphorylated AKT and a decrease of MMP-2 and MMP-9 expression. tTG-knockdown significantly promoted the proliferation and invasion of HTR-8/SVneo cells and inhibited the apoptosis. Furthermore, the PI3K expression level was reduced, and the MMP-2/MMP-9 protein levels were increased. CONCLUSION: Taken together, the present study demonstrated that tTG-overexpression inhibited HTR-8/SVneo cell invasion via reducing the expression of MMP-2 and MMP-9 by activating PI3K/AKT signaling pathway, which may lead to the occurrence or development of PE. The present data provide new insights into modulation of tTG expression as a potential therapeutic target for PE.


Assuntos
Pré-Eclâmpsia , Trofoblastos , Apoptose , Movimento Celular , Feminino , Proteínas de Ligação ao GTP , Humanos , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Placenta/metabolismo , Gravidez , Proteína 2 Glutamina gama-Glutamiltransferase , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Transglutaminases , Trofoblastos/metabolismo
3.
J Recept Signal Transduct Res ; 37(6): 550-559, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28853308

RESUMO

Parkinson's disease (PD) is the second most common neurodegenerative disease in the elderly. In central nervous system, astrocytes regulates neuronal function via the modulation of synaptic transmission and plasticity, secretion of growth factors, uptake of neurotransmitters and regulation of extracellular ion concentrations and metabolic support of neurons. Therefore, C6 astroglial cells have been used to study the in vitro PD model induced by 1-methyl-4-phenyl pyridinium (MPP+). In this study, pre-treatment of insulin inhibited MPP+-induced cell membrane damages on LDH and NO releases, which also inhibited the iNOS and Cox-2 levels. Insulin also up-regulated the PI3K and p-GSK-3ß protein expressions in C6 cells. In addition, MPP+ and/or insulin enhanced the autophagy by increasing LC3-I to LC3-II conversion. Furthermore, MPP+-induced toxicity diminished the integrin ß3, αV, syndecan-1 and -3. Insulin pre-treatment enhanced the phosphorylation of integrin-linked kinase and further induced the integrin and syndecan molecules. These findings suggest that insulin prevents MPP+-induced toxicity through activation of PI3K, p-GSK-3ß, autophagy, integrins and syndecans pathways in C6 glial cells.


Assuntos
Astrócitos/patologia , Autofagia/efeitos dos fármacos , Doença de Parkinson Secundária/genética , Doença de Parkinson/metabolismo , 1-Metil-4-fenilpiridínio/toxicidade , Animais , Apoptose/efeitos dos fármacos , Astrócitos/efeitos dos fármacos , Autofagia/genética , Linhagem Celular , Modelos Animais de Doenças , Humanos , Insulina/farmacologia , Integrina alfaV/genética , Integrina beta3/genética , Óxido Nítrico/metabolismo , Doença de Parkinson/genética , Doença de Parkinson/patologia , Doença de Parkinson Secundária/induzido quimicamente , Doença de Parkinson Secundária/patologia , Fosforilação , Ratos , Transdução de Sinais/efeitos dos fármacos , Sindecana-1/genética , Sindecana-3/genética
4.
J Leukoc Biol ; 111(3): 695-709, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34405445

RESUMO

Dendritic cells (DCs) are efficient antigen-presenting cells that serve as a link between the innate and adaptive immune systems. These cells are broadly involved in cellular and humoral immune responses by presenting antigens to initiate T cell reactions, cytokine and chemokine secretion, T cell differentiation and expansion, B cell activation and regulation, and the mediation of immune tolerance. The functions of DCs depend on their activation status, which is defined by the stages of maturation, phenotype differentiation, and migration ability, among other factors. IL-6 is a soluble mediator mainly produced by a variety of immune cells, including DCs, that exerts pleiotropic effects on immune and inflammatory responses through interaction with specific receptors expressed on the surface of target cells. Here, we review the role of IL-6, when generated in an inflammatory context or as derived from DCs, in modulating the biologic function and activation status of DCs and emphasize the importance of searching for novel strategies to target the IL-6/IL-6 signaling pathway as a means to diminish the inflammatory activity of DCs in immune response or to prime the immunogenic activity of DCs in immunosuppressive conditions.


Assuntos
Células Dendríticas , Interleucina-6 , Diferenciação Celular , Tolerância Imunológica , Interleucina-6/metabolismo , Ativação Linfocitária , Linfócitos T
5.
Biomater Sci ; 10(12): 3346-3358, 2022 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-35588302

RESUMO

After injury, the endometrium cannot self-repair or regenerate because damage to the uterine basal layer often leads to intrauterine adhesions (IUAs), which can cause serious problems such as infertility and recurrent miscarriage. At present, no clinically effective method is available for the treatment of IUAs. With its advantages of being individualized and precise, three-dimensional (3D) bioprinting technology has been used to regenerate various damaged tissues and organs. Granulate colony-stimulating factor (G-CSF) clearly plays a positive role in endometrial regeneration, but precise and individualized drug applications are a prerequisite for improving the therapeutic effect of G-CSF. This study utilized a 3D-printed hydrogel in combination with a sustained-release microsphere (SRM) system to prepare a 3D-printed G-CSF-SRM system (3D microsphere) in vitro. The system advantageously allowed the spatial control of drug distribution and structural individualization. In addition to being long-acting and having a sustained release, the 3D microspheres increased the local concentration of G-CSF. Using a Sprague-Dawley rat IUA model, we confirmed that the 3D microspheres promoted local endometrial regeneration, significantly suppressed endometrium tissue fibrosis, and improved endometrial cell (epithelial and stromal cell) and vascular regeneration. The 3D microspheres significantly improved the endometrial receptivity and restored the pregnancy function of the damaged endometrium. We believe that the 3D-printed G-CSF-SRM hydrogel scaffold design concept may be used to develop a more precise and individualized treatment method for the structural and functional repair of damaged endometrial tissues.


Assuntos
Hidrogéis , Doenças Uterinas , Animais , Preparações de Ação Retardada/uso terapêutico , Endométrio , Feminino , Fator Estimulador de Colônias de Granulócitos/farmacologia , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Humanos , Hidrogéis/química , Microesferas , Gravidez , Impressão Tridimensional , Ratos , Ratos Sprague-Dawley , Regeneração , Aderências Teciduais
6.
Curr Med Sci ; 42(2): 333-340, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35419674

RESUMO

OBJECTIVE: S100A11 is a member of the S100 calcium-binding protein family and has intracellular and extracellular regulatory activities. We previously reported that S100A11 was differentially expressed in the respiratory tracts of asthmatic rats as compared with normal controls. Here, we aimed to analyze the potential of S100A11 to regulate both allergen-induced airway hyperresponsiveness (AHR) as well as acetylcholine (ACh)-induced hypercontractility of airway smooth muscle (ASM) and contraction of ASM cells (ASMCs). METHODS: Purified recombinant rat S100A11 protein (rS100A11) was administered to OVA-sensitized and challenged rats and then the AHR of animals was measured. The relaxation effects of rS100A11 on ASM were detected using isolated tracheal rings and primary ASMCs. The expression levels of un-phosphorylated myosin light chain (MLC) and phosphorylated MLC in ASMCs were analyzed using Western blotting. RESULTS: Treatment with rS100A11 attenuated AHR in the rats. ASM contraction assays showed that rS100A11 reduced the contractile responses of isolated tracheal rings and primary ASMCs treated with ACh. In addition, rS100A11 markedly decreased the ACh-induced phosphorylation of the myosin light chain in ASMCs. Moreover, rS100A11 also suppressed the contractile response of tracheal rings in calcium-free buffer medium. CONCLUSION: These results indicate that S100A11 protein can relieve AHR by relaxing ASM independently of extracellular calcium. Our data support the idea that S100A11 is a potential therapeutic target for reducing airway resistance in asthma patients.


Assuntos
Asma , Cadeias Leves de Miosina , Acetilcolina/metabolismo , Acetilcolina/farmacologia , Acetilcolina/uso terapêutico , Animais , Asma/tratamento farmacológico , Humanos , Pulmão/metabolismo , Contração Muscular , Músculo Liso/metabolismo , Cadeias Leves de Miosina/metabolismo , Cadeias Leves de Miosina/farmacologia , Ratos , Proteínas S100/genética , Proteínas S100/metabolismo , Proteínas S100/farmacologia
7.
Complement Med Res ; 29(2): 136-146, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34875661

RESUMO

OBJECTIVE: Asthma is a highly prevalent respiratory disease that remains difficult to control. Acupuncture, as an important alternative therapeutic modality in preventing and treating asthma, is widely used in the world due to its promising efficacy and safety. Although acupoint selection and combinations are critical to therapeutic effects of acupuncture, its fundamental rules for asthma have not been fully understood. Thus, using data mining, the present study aimed to discover the most effective acupoints and combinations in the acupuncture treatment of asthma. METHODS: Controlled clinical trials (CCTs) of acupuncture treatment for asthma were searched and retrieved from databases including Chinese National Knowledge Infrastructure (CNKI), Wanfang, and PubMed. Data regarding the main acupoints prescribed in these clinical trials was collected and quantified. A network analysis was performed to uncover the interconnections between the acupoints. Additionally, hierarchical clustering analysis and association rule mining were conducted to discover the potential acupoint combinations. RESULTS: A total of 183 CCTs were retrieved. Feishu (BL13), Dingchuan (EX-B1), Dazhui (GV14), Shengshu (BL23), Pishu (BL20), and Fengmen (BL12) appeared to be the most frequently used acupoints for asthma. While the Bladder Meridian of Foot Taiyang, the Governor Vessel, and the Conception Vessel, compared to other meridians, were found to be the more commonly selected meridians. In the acupoint interconnection network, Feishu (BL13), Fengmen (BL12), Dingchuan (EX-B1), and Dazhui (GV14) were defined as key node acupoints. Moreover, acupoint clustering analysis revealed the treatment principle of "facilitating the flow of the lung Qi, tonifying spleen and kidney, and treating both the symptoms and root causes." Association rule mining analysis demonstrated that the combination of Pishu, Shenshu, Feishu, and Dingchuan, as well as that of Feishu, Dazhui, and Fengmen were potential acupoint combinations that should be selected with priority in asthma treatment. CONCLUSION: Based on a data mining analysis of published CCTs, this study provides valuable information regarding the selection of the most effective acupoints and combinations for clinical acupuncture practice and experimental study aimed at the prevention and treatment of asthma.


Assuntos
Terapia por Acupuntura , Asma , Meridianos , Pontos de Acupuntura , Asma/terapia , Mineração de Dados , Humanos
8.
Bioengineered ; 13(4): 9948-9961, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35435106

RESUMO

Congenital heart disease (CHD) is the most common birth defect. Although ASXL transcriptional regulator 3 (ASXL3) has been reported to cause hereditary CHD, ASXL3-mediated mechanisms in heart development remain unclear. In this study, we used dimethyl sulfoxide (DMSO) to induce differentiation in P19 cells, observed cell morphology using light microscopy after ASXL3 knockdown, and determined the levels of associated myocardial cell markers using reverse transcription-quantitative polymerase chain reaction and western blotting. Subsequently, we used microRNA sequencing, messenger RNA (mRNA) sequencing, and bioinformatics to initially identify the possible mechanisms through which ASXL3-related microRNAs and mRNAs affect heart development. The results indicated that DMSO induced P19 cell differentiation, which could be inhibited by ASXL3 knockdown. We screened 1214 and 1652 differentially expressed microRNAs and mRNAs, respectively, through ASXL3 knockdown and sequencing; these differentially expressed miRNAs were largely enriched in PI3K-Akt, mitogen-activated protein kinase, and Rap1 signaling pathways. Additionally, 11 miRNAs associated with heart development were selected through a literature review. Our analysis indicated the involvement of mmu-miR-323-3p in P19 cell differentiation through the PI3K-Akt pathway. In conclusion, ASXL3 may be involved in the regulation of heart development. This comprehensive study of differentially expressed microRNAs and mRNAs through ASXL3 knockdown in P19 cells provides new insights that may aid the prevention and treatment of CHD.


Assuntos
MicroRNAs , Dimetil Sulfóxido , MicroRNAs/genética , MicroRNAs/metabolismo , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
9.
Bioengineered ; 12(2): 12179-12190, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34783299

RESUMO

Growth factor receptor bound protein 7 (GRB7) plays an important role in regulating the growth and metastasis of ovarian cancer. Angiogenesis is the basis for the growth, invasion, and metastasis of malignant tumors. In the current study, we aimed to determine whether GRB7 plays a role in regulating angiogenesis in ovarian cancer. Immunohistochemistry on tissue microarray showed that GRB7 and platelet endothelial cell adhesion molecule-1 (PECAM-1/CD31) protein expression were positively correlated in ovarian cancer tissues. GRB7 knockdown suppressed vascular endothelial growth factor A (VEGFA) expression and reduced VEGFA secretion. The effects of GRB7-silenced SKOV-3 cells on human umbilical vein endothelial cells (HUVECs) were evaluated using a transwell cell co-culture model, which showed that knockdown of GRB7 in SKOV-3 cells suppressed HUVEC proliferation, migration, invasion, and tube formation. Moreover, knockdown of GRB7 in SKOV-3 cells downregulated the expression of proteins associated with angiogenesis, including vascular endothelial growth factor receptor-2 (VEGFR2), mitogen-activated protein kinase kinase 1 (MAP2K1/MEK1), extracellular signal-regulated kinases 1 and 2 (ERK1/2), notch receptor 1 (NOTCH1), and delta-like canonical Notch ligand 4 (DLL4) in HUVECs. In conclusion, knockdown of GRB7 in ovarian cancer cells is an attractive potential therapeutic target for the suppression of angiogenesis in ovarian cancer. GRB7 may regulate angiogenesis through VEGFA/VEGFR2 signaling and its downstream pathways.


Assuntos
Proteína Adaptadora GRB7/metabolismo , Técnicas de Silenciamento de Genes , Neovascularização Patológica/metabolismo , Neoplasias Ovarianas/irrigação sanguínea , Neoplasias Ovarianas/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Feminino , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Neoplasias Ovarianas/patologia , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo
10.
Cell Prolif ; 54(2): e12968, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33332660

RESUMO

OBJECTIVES: Pre-eclampsia is a leading cause of morbidity and mortality during pregnancy. Although the two forms of this disorder, early- (EOPE) and late-onset of pre-eclampsia (LOPE) are different, the underlying pathology remains elusive. We aim to unravel the difference and to identify novel biomarkers for EOPE and LOPE. MATERIALS AND METHODS: A complete comparison of both placental and peripheral blood transcriptomes was performed to investigate the pathology of pre-eclampsia. Single-cell transcriptomics of the maternal-fetal interface were integrated to identify novel biomarkers for EOPE and LOPE which were further verified at protein or mRNA level in patients. RESULTS: We found that the transcriptomes of placentae from EOPE, but not LOPE, were significantly different from their respective controls. Conversely, the transcriptomes of peripheral blood from LOPE were more different from their controls than EOPE. Importantly, we identified that several classical biomarkers of pre-eclampsia were expressed specifically in extravillous trophoblast and syncytiotrophoblast and only upregulated in EOPE, suggesting they should not be applied to all pre-eclampsia patients in general. We further identified novel biomarkers for EOPE and LOPE from differentially expressed genes (DEGs) of placental and peripheral blood, respectively. The new biomarkers EBI3, IGF2, ORMDL3, GATA2 and KIR2DL4 were experimentally verified with patient blood samples. CONCLUSION: Our data demonstrate distinct pathology of EOPE and LOPE, and uncover new biomarkers that can be applied in diagnosis for pre-eclampsia.


Assuntos
Biomarcadores/metabolismo , Pré-Eclâmpsia/patologia , Transcriptoma , Biomarcadores/sangue , Estudos de Casos e Controles , Biologia Computacional , Feminino , Fator de Transcrição GATA2/sangue , Fator de Transcrição GATA2/metabolismo , Humanos , Interleucinas/sangue , Interleucinas/metabolismo , Transtornos de Início Tardio , Proteínas de Membrana/sangue , Proteínas de Membrana/metabolismo , Antígenos de Histocompatibilidade Menor/sangue , Antígenos de Histocompatibilidade Menor/metabolismo , Placenta/metabolismo , Pré-Eclâmpsia/metabolismo , Gravidez , Mapas de Interação de Proteínas , RNA Mensageiro/metabolismo , Análise de Sequência de RNA , Análise de Célula Única
11.
Org Lett ; 23(12): 4705-4709, 2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34060853

RESUMO

An iron-sulfur complex formed by the simple mixture of FeCl3 with S3•- generated in situ from K2S is developed and applied to selective aerobic oxidation of terminal alkenes. The reaction was carried out under an atmosphere of O2 (balloon) and could proceed on a gram scale, expanding the application of S3•- in organic synthesis. This study also encourages us to explore the application of an Fe-S catalyst in organic reactions.

12.
Biomol Ther (Seoul) ; 28(1): 104-109, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31474032

RESUMO

Probenecid is a representative drug used in the treatment of gout. A recent study showed that probenecid effectively inhibits oxidative stress in neural cells. In the present study, we investigated whether probenecid can affect osteoclast formation through the inhibition of reactive oxygen species (ROS) formation in RAW264.7 cells. Lipopolysaccharide (LPS)-induced ROS levels were dose-dependently reduced by probenecid. Fluorescence microscopy analysis clearly showed that probenecid inhibits the generation of ROS. Western blot analysis indicated that probenecid affects two downstream signaling molecules of ROS, cyclooxygenase 2 (COX-2) and c-Jun N-terminal kinase (JNK). These results indicate that probenecid inhibits ROS generation and exerts antiosteoclastogenic activity by inhibiting the COX-2 and JNK pathways. These results suggest that probenecid could potentially be used as a therapeutic agent to prevent bone resorption.

13.
J Vis Exp ; (162)2020 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-32925876

RESUMO

A high platform can fix rats without restriction and completely expose the acupoints on the back during acupuncture manipulation. This article describes methods for the fabrication of the high platform, establishes a rat model of asthma and measures changes in respiratory function using a noninvasive and real-time whole-body plethysmography (WBP) system.


Assuntos
Terapia por Acupuntura , Asma/terapia , Pontos de Acupuntura , Animais , Asma/fisiopatologia , Modelos Animais de Doenças , Humanos , Masculino , Nebulizadores e Vaporizadores , Agulhas , Pletismografia Total , Ratos , Respiração
14.
Org Lett ; 22(22): 9128-9132, 2020 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-33147971

RESUMO

A novel visible-light-photocatalytic deuterated thiomethylation/methylselenation of aryldiazonium salts utilizing S/Se-methyl-d3 sulfonothioate has been developed. The mild conditions and the various functional groups provide a green protocol for the efficient and rapid introduction of the S-CD3 or Se-CD3 group with useful levels of deuterium content (>91% D). Trideuteromethyl sulfoxides have also been successfully chemoselectively observed by simple atmospheric changes under photocatalytic conditions.

15.
J Clin Anesth ; 34: 535-9, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27687447

RESUMO

BACKGROUND: This study aimed to investigate the risk factors of intraoperative anesthesia adverse events (IAAEs) in children with laryngeal diseases. METHODS: We retrospectively recruited 118 children with laryngeal diseases who underwent surgical therapy. Based on medical history and preoperative imaging diagnosis, the baseline data, including sex, age, weight, onset age, the number of operation, the degree of airway obstruction, the nature of disease, the location of disease, complications, tracheotomy, and trachea intubation, were defined and recorded. IAAEs, such as pulse oxygen saturation (SpO2) decline, heart rate (HR) decline, emergency orotracheal intubation, emergency tracheotomy, and remaining intubated postoperatively, were also recorded. The risk factors for IAAEs were identified using multivariate logistic regression model. RESULTS: Increasing severity of airway obstruction and the presence of pneumonia were risk factors for SpO2 and HR decline in children with laryngeal diseases. Older age, supraglottic rather than subglottic disease, and trachea intubation rather than unprotected airway during surgery were protective factors for SpO2 decline. Furthermore, severe airway obstruction increased risks of emergency orotracheal intubation and remaining intubated postoperatively, whereas supraglottic rather than subglottic disease were protective factors for emergency orotracheal intubation and remaining intubated postoperatively. Only HR decline was found to be associated with the presence of congenital heart disease. CONCLUSIONS: The severe airway obstruction increases the risk of SpO2 decline and HR decline as well as the possibility of perioperative emergency orotracheal intubation and remaining intubated postoperatively, whereas supraglottic surgery and surgery performed under endotracheal intubation reduce the incidence rates of these IAAEs in children with laryngeal diseases.


Assuntos
Anestesia Geral/efeitos adversos , Complicações Intraoperatórias/epidemiologia , Doenças da Laringe/cirurgia , Obstrução das Vias Respiratórias/complicações , Monitorização Transcutânea dos Gases Sanguíneos , Feminino , Frequência Cardíaca , Humanos , Incidência , Lactente , Complicações Intraoperatórias/sangue , Complicações Intraoperatórias/etiologia , Intubação Intratraqueal/estatística & dados numéricos , Doenças da Laringe/complicações , Masculino , Oxigênio/sangue , Pneumonia/complicações , Estudos Retrospectivos , Fatores de Risco , Traqueostomia/estatística & dados numéricos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA