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1.
ACS Omega ; 9(12): 14520-14529, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38559968

RESUMO

Gastrodia elata Blume (G. elata) is a well-known medicine food homology plant widely used in treating neurological disorders such as Alzheimer's disease (AD). Here, undiscovered gastrodin derivatives were systematically studied. Seven novel gastrodin derivatives (1-7), including a unique gastrodin isocitrate (1) and six differently substituted parishin derivatives (2-7), were isolated. Structural identification was mainly based on 1D and 2D NMR data, high-resolution ESI-MS data, and HPLC analysis. Notably, the stereochemistry of 1 was further elucidated by ECD calculations. Compounds 1 and 6 showed neuroprotective effects on the H2O2-induced PC12 cell injury model. Molecular docking analysis exhibited that 1 and 6 had good affinities with three popular AD-related targets. These findings not only enriched the chemical diversity but also revealed potential active components in G. elata.

2.
Int J Biol Macromol ; 263(Pt 1): 130207, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38365156

RESUMO

Polysaccharides have been widely used in the development of natural drugs and health food. However, polysaccharide characterization lags due to inherently complicated features and the limitations of existing detection approaches. We aimed to provide new insight into the fine structure and conformational visualization of polysaccharides from Gastrodia elata Blume, a medicinal and edible plant. A water-soluble polysaccharide (GEP2-6) with the high molecular weight of 2.7 × 106 Da was first obtained, and its purity reached 99.2 %. Chemical and spectroscopic analyses jointly revealed that GEP2-6 was a glucan linked by α-(1 â†’ 4) and α-(1 â†’ 6) glycosidic bonds. After enzymolysis, the local structure of GEP2-6 included α-1,4-Glcp, α-1,6-Glcp, α-1,4,6-Glcp, and α-1-Glcp at a molar ratio of 31.27∶1.32∶1.08∶0.93. The glycosidic linkage pattern of repeating units was further simulated by a glycan database and spatial examination software. The good dissolution performance was interpreted by dynamics simulation and practical molecular characteristics. Spherical flexible chains and the porous stable conformation were corroborated using atomic force microscopy. In addition, GEP2-6 could effectively scavenge DPPH and hydroxyl radicals as a promising natural antioxidant. These efforts will contribute to the expansion of clinical applications of this G. elata polysaccharide and the structural elucidation for macromolecular polysaccharides combined with traditional and modern analysis techniques.


Assuntos
Gastrodia , Extratos Vegetais , Extratos Vegetais/química , Glucanos , Gastrodia/química , Simulação de Dinâmica Molecular , Peso Molecular , Água , Polissacarídeos/química
3.
Chin Med ; 17(1): 130, 2022 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-36403018

RESUMO

BACKGROUND: Traditional Chinese medicine (TCM) has been used to treat various diseases for thousands of years. However, the uncertainty of dosage as well as the lack of systemic evaluation of pharmacology and toxicology is one major reason why TCM remains mysterious and is not accepted worldwide. Hence, we aimed to propose an integrated dose-response metabolomics strategy based on both therapeutic effects and adverse reactions to guide the TCM dosage in treatment. METHODS: The proposed methodology of integrated dose-response metabolomics includes four steps: dose design, multiple comparison of metabolic features, response calculation and dose-response curve fitting. By comparing the changes of all metabolites under different doses and calculating these changes through superposition, it is possible to characterize the global disturbance and thus describe the overall effect and toxicity of TCM induced by different doses. Rhubarb, commonly used for constipation treatment, was selected as a representative TCM. RESULTS: This developed strategy was successfully applied to rhubarb. The dose-response curves clearly showed the efficacy and adverse reactions of rhubarb at different doses. The rhubarb dose of 0.69 g/kg (corresponding to 7.66 g in clinic) was selected as the optimal dose because it was 90% of the effective dose and three adverse reactions were acceptable in this case. CONCLUSION: An integrated dose-response metabolomics strategy reflecting both therapeutic effects and adverse reactions was established for the first time, which we believe is helpful to uncover the mysterious veil of TCM dosage. In addition, this strategy benefits the modernization and internationalization of TCM, and broadens the application of metabolomics.

4.
Chin Med ; 17(1): 50, 2022 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-35473719

RESUMO

BACKGROUND: Rhei Radix et Rhizoma (rhubarb), as one of the typical representatives of multi-effect traditional Chinese medicines (TCMs), has been utilized in the treatment of various diseases due to its multicomponent nature. However, there are few systematic investigations for the corresponding effect of individual components in rhubarb. Hence, we aimed to develop a novel strategy to fuzzily identify bioactive components for different efficacies of rhubarb by the back propagation (BP) neural network association analysis of ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry for every data (UPLC-Q-TOF/MSE) and integrated effects. METHODS: Through applying the fuzzy chemical identification, most components of rhubarb were classified into different chemical groups. Meanwhile the integration effect values of different efficacies can be determined by animal experiment evaluation and multi-attribute comprehensive indexes. Then the BP neural network was employed for association analysis of components and different efficacies by correlating the component contents determined from UPLC-Q-TOF/MSE profiling and the integration effect values. Finally, the effect contribution of one type of components may be totaled to demonstrate the universal and individual characters for different efficacies of rhubarb. RESULTS: It suggested that combined anthraquinones, flavanols and their polymers may be the universal character to the multi-functional properties of rhubarb. Other components contributed to the individuality of rhubarb efficacies, including stilbene glycosides, anthranones and their dimers, free anthraquinones, chromones, gallic acid and gallotannins, butyrylbenzenes and their glycosides. CONCLUSIONS: Our findings demonstrated that the bioactive components for different efficacies of rhubarb were not exactly the same and can be systematically differentiated by the network-oriented strategy. These efforts will advance our knowledge and understanding of the bioactive components in rhubarb and provide scientific evidence to support the expansion of its use in clinical applications and the further development of some products based on this medicinal herb.

5.
Ying Yong Sheng Tai Xue Bao ; 33(12): 3388-3394, 2022 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-36601845

RESUMO

The utilization of sewage sludge in forests is an important way of recycling. However, the effect of sewage sludge application on woody plant root growth has been rarely reported. The effects of surface application and mixed application of sewage sludge (mass ratio in 10%) on the dynamics in root morphology of a fast-growing tree species (Neolamarckia cadamba), soil pH, electric conductivity, and heavy metal content of roots in different soil layers were analyzed by a rhizobox experiment. The relationship between root length and soil pH value, electric conducti-vity, and root heavy metal content were further analyzed. Results showed that mixed application of sewage sludge inhibited root length, root surface area, and root volume. After 120 and 240 days of mixed application, total root length in the 0-20 cm soil layer was 76.9% and 67.4% of that of no sewage sludge application, respectively. Surface application of sewage sludge did not affect root length and root surface area but increased root volume. The mixed application of sewage sludge significantly increased soil pH, electric conductivity, and root heavy metal content. Root Cd contents in 0-20 cm and 20-40 cm soil layers with the mixed application of sewage sludge were 11.5 and 10.0 times as that of no sewage sludge application, respectively. Soil electric conductivity had a significant nega-tive correlation with root length in 0-20 cm soil layer among different treatments. Root Cd content had a significant negative correlation with root length in both the surface and the mixed applications of sewage sludge. These results indicated that mixed application of sewage sludge could inhibit N. cadamba root growth mainly by increasing soil electric conductivity and root Cd content, while the surface application of sewage sludge did not affect root growth.


Assuntos
Metais Pesados , Poluentes do Solo , Poluentes do Solo/análise , Esgotos/química , Cádmio , Solo/química , Metais Pesados/análise
6.
J Sep Sci ; 44(22): 4082-4091, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34514725

RESUMO

Red and yellow pigments are the major ingredients of safflower, often used to color food and cosmetics. Carthamin was the main component of red pigment and hydroxysafflor yellow A and anhydrosafflower yellow B were representative components of yellow pigment. Plant metabolomics and semi-quantitative analysis were used to analyze the changes of pigment composition during the blooming period, especially these characteristic components. Carthamin, hydroxysafflor yellow A, anhydrosafflower yellow B, and other components were screened out as differential metabolites based on plant metabolomics. Then semi-quantitative analysis was used to quantify these three representative components of pigments. Experimental results showed that the content of pigments has dynamic changes along with flowering, in the early blooming period, yellow pigment accumulated much and red pigment was low in content. In the middle period, the accumulation rate of the yellow pigment slowed down and content was stabilized. In the next step, the content of yellow pigments gradually decreased, and the content of red pigments gradually increased. Later, the level of yellow pigment decreased significantly, and the accumulation rate of red pigment increased significantly. Last, the appearance color of safflower was red, with yellow parts barely visible, and accumulation of red pigment was the highest and of the yellow pigment was the lowest in content.


Assuntos
Pigmentos Biológicos/metabolismo , Carthamus tinctorius/química , Chalcona/análogos & derivados , Chalcona/metabolismo , Cromatografia Líquida de Alta Pressão , Flores/química , Glucosídeos/metabolismo , Metabolômica , Plantas
7.
World J Clin Cases ; 9(23): 6900-6906, 2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34447840

RESUMO

BACKGROUND: Scrub typhus is an acute infectious disease caused by rickettsia infection. The diagnosis is based on eschar, and clinical manifestations can range from asymptomatic to multiorgan dysfunction. CASE SUMMARY: We report the case of a 35-year-old man living in Zhuhai, Guangdong, China, who had repeated high fever with a maximum body temperature of 40.2 °C and elevated white blood cells and procalcitonin levels. After 7 d of persistent high fever, the patient developed rash, abdominal pain, and symptoms of peritonitis. Within 24 h after admission, the patient developed diffuse peritonitis and pneumonedema, requiring ventilator support in the intensive care unit. However, there was no eschar on the body, and the first Weil-Felix test was negative. Taking into account that the patient had a history of jungle activities, doxycycline combined with meropenem was selected. The patient improved, healed, and was discharged after a week. The diagnosis of scrub typhus was confirmed by a repeat Weil-Felix test (Oxk 1:640), and pathology of the appendix resected by laparotomy suggests vasculitis. CONCLUSION: This rare presentation of peritonitis, pulmonary edema, and pancreatitis caused by scrub typhus reminds physicians to be alert to the possibility of scrub typhus.

8.
J Sep Sci ; 43(16): 3170-3182, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32506800

RESUMO

Safflower has both medicinal and edible values but research on its nutrient composition is still lacking. This study was established for the quantitative determination of 28 nucleosides, nucleobases, and amino acids based on the ultra-performance liquid chromatography coupled with triple-quadrupole linear ion-trap tandem mass spectrometry. Analysis of 30 batches of safflower from different producing areas indicated that the contents of l-proline, l-asparagine, l(+)-arginine, l-serine, l-histidine, uracil, guanosine, and uridine was high in safflower. Principle component analysis and cluster analysis found that samples from different regions could be distinguished well, and samples from the same area could be clustered into one class, different geographical environments may cause the differences of nucleosides, nucleobases, and amino acids in safflower. The analysis of principal component analysis, cluster analysis, and counter propagation artificial neural network show similar results. Then the content of nucleosides, nucleobases, and essential amino acids were compared, and found that the content in safflower from Gansu was higher than those from other regions, and there was a little difference between the samples from Xinjiang, Sichuan, and Yunnan. This research revealed the composition of nucleosides, nucleobases, and amino acids in safflower, and provided a theoretical basis for utilization of safflower.


Assuntos
Aminoácidos/análise , Carthamus tinctorius/química , Nucleosídeos/análise , Cromatografia Líquida de Alta Pressão , Análise por Conglomerados , Análise de Componente Principal , Espectrometria de Massas em Tandem
9.
J Pharm Biomed Anal ; 177: 112837, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31493746

RESUMO

The ambiguity of dose-effect relationship of many traditional Chinese medicines (TCMs) has always influenced their rational use in TCM clinic. Rhubarb, a preferred representative of cathartic TCM, is currently widely used that results in a diversity of its dosage. The aim of this study was to use an integrated metabolomics strategy to simultaneously reveal dose-effect relationship and therapeutic mechanisms of different efficacy of rhubarb in constipation rats. Six doses of rhubarb (0.135, 0.27, 0.81, 1.35, 4.05, and 8.1 g/kg) were examined to elucidate the laxative and fire-purging effects by pathological sections and UPLC-Q-TOF/MSE. The results showed that there existed serious lesions in the stomach and colon of model rats. And conditions were basically improved to some extent in rhubarb-treated groups. Through relative distance calculation based on metabolomics score plots, it suggested that the effective dose threshold (EC20-EC80 range) of rhubarb was from 0.31 to 4.5 g/kg (corresponding to 3.44-50.00 g in the clinic) in rat serum and 0.29-2.1 g/kg (corresponding to 3.22-23.33 g in the clinic) in feces. Then, 33 potential biomarkers were identified in total. Functional pathway analysis revealed that the alterations of these biomarkers were associated with 15 metabolic pathways, mainly including arachidonic acid metabolism, glycerophospholipid metabolism, steroid biosynthesis, primary bile acid biosynthesis and sphingolipid metabolism. Of note, different doses of rhubarb could alleviate endogenous disorders to varying degrees through regulating multiple perturbed pathways to the normal state, which might be in a dose-dependent manner and involved in therapeutic mechanisms. To sum up, integrated serum and fecal metabolomics obtained that rhubarb ranging from 0.31 to 2.1 g/kg is safe and effective for constipation treatment. Also, our findings showed that the robust metabolomics techniques would be promising to be more accurately used in the dose-effect studies of complex TCM, and to clarify syndrome pathogenesis and action mechanisms in Chinese medicine.


Assuntos
Constipação Intestinal/tratamento farmacológico , Medicamentos de Ervas Chinesas/administração & dosagem , Laxantes/administração & dosagem , Redes e Vias Metabólicas/efeitos dos fármacos , Rheum/química , Animais , Ácido Araquidônico/análise , Ácido Araquidônico/metabolismo , Biomarcadores/sangue , Biomarcadores/metabolismo , Cromatografia Líquida de Alta Pressão/métodos , Constipação Intestinal/sangue , Constipação Intestinal/metabolismo , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Medicamentos de Ervas Chinesas/isolamento & purificação , Fezes/química , Glicerofosfolipídeos/análise , Glicerofosfolipídeos/metabolismo , Humanos , Laxantes/isolamento & purificação , Masculino , Metaboloma/efeitos dos fármacos , Metabolômica/métodos , Ratos
10.
Zhongguo Zhong Yao Za Zhi ; 44(10): 2131-2138, 2019 May.
Artigo em Chinês | MEDLINE | ID: mdl-31355572

RESUMO

The dose-toxicity-effect relationship between licorice combined with rhubarb in purgation was studied. A total of 108 ICR mice were divided into control group,model group,positive group,low,medium and high-dose rhubarb groups,and low,medium and high-dose rhubarb-liquorice decoction group. After 6 days of continuous administration of loperamide hydrochloride,the constipation model of mice was replicated,and each group was given lactulose,different doses of rhubarb and rhubarb-liquorice decoction for 14 days. After administration,the defecation characteristics,blood biochemistry,liver,kidney and colon pathological changes in each group were compared. Based on the objective weight given by factor analysis,the dose-toxicity-effect relationship was comprehensively analyzed by multi-index scoring method. Two common factors were extracted by factor analysis,representing effect and toxicity respectively. The results showed that rhubarb could exert a diarrhea effect at the dosage of 1/2,2 and 8 times of the high limit set forth in the Chinese Pharmacopoeia,increase the defecation volume and the intestinal tract propulsion rate,reduce the time of anal and the oral transmission,and increase the water content of feces. The combination with licorice could alleviate its diarrhea effect,especially at the dosage of 1/2 times of the high limit set forth in the Chinese Pharmacopoeia. However,rhubarb showed obvious hepatic and colon toxicities at the dosage of 2 and 8 times of the high limit set forth in the Chinese Pharmacopoeia,and the combination with licorice could significantly reduce its toxicity. It shows that licorice has a " mediating" effect on rhubarb by alleviating the purgation property and reducing the toxicity.


Assuntos
Catárticos/farmacologia , Glycyrrhiza/química , Extratos Vegetais/farmacologia , Rheum/química , Animais , Colo , Relação Dose-Resposta a Droga , Rim , Fígado , Camundongos , Camundongos Endogâmicos ICR , Testes de Toxicidade
11.
J Ethnopharmacol ; 238: 111868, 2019 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-30981706

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Rhei Radix et Rhizoma (rhubarb), as the preferred representative of cathartic drugs of traditional Chinese medicine (TCM), has a long history of medicinal use and multifarious functions that produce a wide range of dosage. In modern times, rhubarb and its prescriptions are not only used to treat common clinical diseases, but also achieve good results in the treatment of acute, dangerous, severe and difficult diseases. However, rhubarb also has an alias called "General", which means that its efficacy is relatively rapid. AIM OF THE STUDY: The present study was conducted to simultaneously elucidate dosage-effect relationship of rhubarb of different efficacy, "Removing accumulation with purgation" (E1) and "Clearing heat and purging fire" (E2), providing reference for the safe and effective usage of rhubarb. MATERIALS AND METHODS: Three-week-old rats were randomly divided into the normal control group (Con.), model group (Mod.) and rhubarb groups with six doses (0.135, 0.27, 0.81, 1.35, 4.05, 8.1 g/kg). We established a constipation model with gastrointestinal accumulated heat induced by dyspepsia, taking defecation characteristics observed by metabolic cages, alvine pushing rate, gastrointestinal hormones in serum, etc., as indicators of E1, and taking TG, Na+-K+-ATPase, inflammatory factors and proteins, etc., as indicators of E2. The factor analytic approach was used to systematically evaluate the two effects and analyze the corresponding dosage-effect relationship. RESULTS: The levels of Gas, AchE, TG, Na+-K+-ATPase, TNF-α, IL-1ß, (p-)NF-κB p65, (p-)p38, (p-)ERK and p-JNK in model rats increased significantly while the levels of defecation, fecal water content, MTL, SS, ET, NTS, VIP, JNK and TLR4 decreased. Compared with the Mod., in rhubarb groups, the increase of faeces, alvine pushing rate, most gastrointestinal hormones, etc., reflected the therapeutic efficacy of E1, and the reduction of TG, Na+-K+-ATPase, expression levels of inflammatory indexes, etc., reflected the impact of E2. After the analysis, the effective threshold dose ranging from 0.67 to 5.37 g/kg (corresponding to 7.44-59.67 g in the clinic) was in the EC20-EC80 range for E1 treatment and from 0.78 to 5.60 g/kg (equivalently clinical 8.67-62.22 g) was for E2 treatment. And the 1.6- and 1.2-fold rhubarb highest dose of Chinese Pharmacopoeia might be the optimal doses for E1 and E2 respectively. In general, however, the concentration of rhubarb liquid for overall efficacy is suggested to be between middle and highest dose of Chinese Pharmacopoeia. CONCLUSION: A constipation model was used to elucidate two main effects of rhubarb, which was consistent with the characteristics of TCM syndrome. In the wide range of rhubarb dosage, low doses might have little or no effect and although high concentrations of rhubarb liquid enhanced curative efficacy, it would also have certain side effects on the body. Therefore, scientific-based experiments and rational analysis by mathematical models could contribute to the safe and effective application of rhubarb in the clinic.


Assuntos
Constipação Intestinal/tratamento farmacológico , Laxantes/farmacologia , Extratos Vegetais/farmacologia , Rheum/química , Animais , Colo/efeitos dos fármacos , Colo/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Inflamação/metabolismo , Laxantes/química , Masculino , Medicina Tradicional Chinesa , Fitoterapia , Extratos Vegetais/química , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley
12.
Oxid Med Cell Longev ; 2019: 8636835, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30911351

RESUMO

Ginkgo ketoester tablets (GT) and donepezil were a clinically used combination for the treatment of Alzheimer's disease (AD). The aim of the study was undertaken to investigate the antiamnesic effects of the two drugs alone and in combination through in vivo models of the Morris water maze along with in vitro antioxidants, acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE). The potential mechanisms were speculated by the activities of acetylcholine (ACh), AChE, superoxide dismutase (SOD), and malondialdehyde (MDA) and the protein expression of brain-derived neurotrophic factor (BDNF) and tyrosine protein kinase B (TrkB). The combination group showed a concentration-dependent inhibition of cholinesterase and antioxidation. As far as its mechanism was concerned, the combination of two drugs exerted excellent effects on oxidative stress, cholinergic pathway damage, and inactivation of the BDNF-TrkB signaling pathway. Additionally, to elucidate the binding mechanism of GT active ingredients into the structure of AChE, the results of molecular docking studies indicated that hydrogen and/or hydrophobic bonds might play an important role in their binding process. Thus, the combination of drugs could treat AD perfectly and further verify the scientific rationality of clinical medication.


Assuntos
Amnésia/tratamento farmacológico , Donepezila/uso terapêutico , Ginkgo biloba/química , Transtornos da Memória/induzido quimicamente , Transtornos da Memória/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Acetilcolina/metabolismo , Acetilcolinesterase , Amnésia/patologia , Animais , Benzotiazóis/química , Compostos de Bifenilo/química , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Inibidores da Colinesterase/farmacologia , Transtornos Cognitivos/tratamento farmacológico , Donepezila/farmacologia , Quimioterapia Combinada , Ginkgolídeos/química , Ligantes , Malondialdeído/metabolismo , Camundongos Endogâmicos ICR , Simulação de Acoplamento Molecular , Picratos/química , Extratos Vegetais/farmacologia , Receptor trkB/metabolismo , Escopolamina , Ácidos Sulfônicos/química , Superóxido Dismutase/metabolismo , Comprimidos
13.
J Pharm Anal ; 9(5): 312-323, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31929940

RESUMO

Although compatibility is highly advocated in traditional Chinese medicine (TCM), inappropriate combination of some herbs may reduce the therapeutic action and even produce toxic effects. Kansui and licorice, one of TCM "Eighteen Incompatible Medicaments", are the most representative cases of improper herbal combination, which may still be applied simultaneously under given conditions. However, the potential mechanism of their compatibility and incompatibility is unclear. In the present study, two different ratios of kansui and licorice, representing their compatibility and incompatibility respectively, were designed to elucidate their interaction by comparative plasma/tissue metabolomics and a heatmap with relative fold change. As a result, glycocholic acid, prostaglandin F2a, dihydroceramide and sphinganine were screened out as the principal alternative biomarkers of compatibility group; sphinganine, dihydroceramide, arachidonic acid, leukotriene B4, acetoacetic acid and linoleic acid were those of incompatibility group. Based on the values of biomarkers in each tissue, the liver was identified as the compatible target organ, while the heart, liver, and kidney were the incompatible target organs. Furthermore, important pathways for compatibility and incompatibility were also constructed. These results help us to better understand and utilize the two herbs, and the study was the first to reveal some innate characters of herbs related to TCM "Eighteen Incompatible Medicaments".

14.
Chem Commun (Camb) ; 52(26): 4796-9, 2016 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-26955799

RESUMO

An effective single crystal to single crystal transformation from a tetrahedral Ni cage to an FeNi cage was demonstrated. The iron(ii) centers of the FeNi cage can be induced to display spin crossover behaviors with an increasing amount of Fe(II) ions. The SCSC metal-center exchange provides a powerful approach to modify solid magnetic properties.

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