Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 13 de 13
Filtrar
Añadir filtros








Intervalo de año
1.
Chinese Journal of Anesthesiology ; (12): 1380-1384, 2022.
Artículo en Chino | WPRIM | ID: wpr-994122

RESUMEN

Objective:To evaluate role of Ras homolog gene family member A (RhoA)/Rho-associated coiled-coil protein kinase 2 (ROCK2) signaling pathway in trilobatin-induced reduction of cerebral ischemia-reperfusion (I/R) injury in rats.Methods:Eighty clean-grade healthy male Sprague-Dawley rats, aged 6-8 weeks, weighing 230-280 g, were divided into 4 groups ( n=20 each) using a random number table method: sham operation group (group S), cerebral I/R group (group IR), cerebral I/R plus trilobatin group (group T) and cerebral I/R plus trilobatin plus RhoA/ROCK2 signaling pathway agonist AA group (group A). The model of focal cerebral I/R injury was developed by middle cerebral artery occlusion in anesthetized animals.Trilobatin 15 mg/kg was given by gavage twice a day for 3 consecutive days in T and A groups.RhoA/ROCK2 signaling pathway agonist AA 10 mg/kg was intraperitoneally injected before each administration by gavage in group A. Neurobehavioral score was assessed at 24 h of reperfusion, then the rats were sacrificed, and the hippocampal tissues were isolated for determination of the apoptosis rate of hippocampal neurons (by flow cytometry), cerebral infarction volume (by TTC staining), and expression of phosphorylated RhoA (p-RhoA), ROCK2 and cleaved caspase-3 (by Western blot) and for microscopic examination of ultrastructure of hippocampal neurons (with a transmission electron microscope). Results:Compared with group S, the neurobehavioral score, apoptosis rate of hippocampal neurons, and cerebral infarction volume were significantly increased, the expression of p-RhoA, ROCK2 and cleaved caspase-3 was up-regulated ( P<0.05), and the pathological damage to hippocampal neurons was aggravated in group IR.Compared with group IR, the neurobehavioral score, apoptosis rate of hippocampal neurons and cerebral infarction volume were significantly decreased, the expression of p-RhoA, ROCK2 and cleaved caspase-3 was down-regulated ( P<0.05), and the pathological damage to hippocampal neurons was alleviated in group T. Compared with group T, the neurobehavioral score, apoptosis rate of hippocampal neurons, and cerebral infarction volume were significantly increased, the expression of p-RhoA, ROCK2 and cleaved caspase-3 was up-regulated ( P<0.05), and the pathological damage to hippocampal neurons was aggravated in group A. Conclusions:RhoA/ROCK2 signaling pathway is involved in trilobatin-induced reduction of cerebral I/R injury, which may be related to inhibition of apoptosis in hippocampal neurons of rats.

2.
Chinese Journal of Anesthesiology ; (12): 171-175, 2022.
Artículo en Chino | WPRIM | ID: wpr-933313

RESUMEN

Objective:To evaluate the role of brain-derived neurotrophic factor (BDNF)/tyrosine kinase receptor B (TrkB) signaling pathway in 17β estradiol-induced reduction of long-term cognitive impairment induced by multiple propofol anesthesia in developing rats.Methods:Eighty 7-day-old clean-grade healthy newborn Sprague-Dawley rats of both sexes, weighing 11-17 g, were divided into 4 groups ( n=20 each) using a random number table method: control group (group C), propofol group (group P), 17β estradiol plus propofol group (EP group) and 17β estradiol plus propofol plus BDNF/TrkB signaling pathway blocker K252a group (K group). Propofol 80 mg/kg was intraperitoneally injected every day for 5 days in P, EP and K groups.The equal volume of fat emulsion was given instead in group C. In EP and K groups, 17β estradiol 600 μg/kg was subcutaneously injected at 30 min before propofol injection.BDNF/TrkB signaling pathway blocker K252a 100 μg/kg was intraperitoneally injected in group K. Morris water maze test was performed on days 30-34 after birth to assess the cognitive function.The rats were sacrificed after the end of Morris water maze test, and the hippocampal tissues were removed for determination of the apoptosis rate of hippocampal neurons (by flow cytometry), expression of BDNF, p-Trkb and cleaved caspase-3 (by Western blot and immunofluorescence), and expression of Bcl-2 and Bax mRNA (by real-time polymerase chain reaction) and for microscopic examination of the pathological changes in hippocampal CA1 region (with a light microscope). Bax mRNA/Bcl-2 mRNA ratio was calculated. Results:Compared with group C, the escape latency was significantly prolonged, the number of crossing the original platform was reduced, the expression of BDNF and p-TrkB was down-regulated, the expression of cleaved caspase-3 was up-regulated, the apoptosis rate of hippocampal neurons and Bax mRNA/Bcl-2 mRNA ratio were increased ( P<0.05), and the pathological changes in hippocampal CA1 region were accentuated in group P. Compared with group P, the escape latency was significantly shortened, the number of crossing the original platform was increased, the expression of BDNF and p-TrkB was up-regulated, the expression of cleaved caspase-3 was down-regulated, the apoptosis rate of hippocampal neurons and Bax mRNA/Bcl-2 mRNA ratio were decreased( P<0.05), and the pathological changes in hippocampal CA1 region were attenuated in group EP.Compared with group EP, the escape latency was significantly prolonged, the number of crossing the original platform was reduced, the expression of BDNF and p-TrkB was down-regulated, the expression of cleaved caspase-3 was up-regulated, the apoptosis rate of hippocampal neurons and Bax mRNA/Bcl-2 mRNA ratio were increased( P<0.05), and the pathological changes in hippocampal CA1 region were accentuated in group K. Conclusions:BDNF/TrkB signaling pathway is involved in 17β estradiol-induced reduction of long-term cognitive impairment induced by multiple propofol anesthesia in developing rats.

3.
Chinese Journal of Anesthesiology ; (12): 105-108, 2019.
Artículo en Chino | WPRIM | ID: wpr-745673

RESUMEN

Objective To evaluate the effect of bone marrow-derived mesenchymal stem cells (BMSCs) on transforming growth factor-β1 (TGF-β1)/Smad signaling pathway during acute lung injury (ALI) in rats.Methods Healthy clean-grade adult male Sprague-Dawley rats,aged 4-5 weeks,weighing 100-120 g,were selected,and BMSCs were prepared and cultured in vitro.Eighty-four healthy clean-grade adult male Sprague-Dawley rats,aged 4 weeks,weighing 170-190 g,were selected and divided into 4 groups (n=21 each) using a random number table method:control group (group C),group ALI,ALI plus BMSCs group (group ALI + BMSCs),and ALI plus phosphate buffer solution (PBS)group (group ALI+PBS).ALI was induced by intraperitoneally injecting 5 mg/kg lipopolysaccharide 0.5 ml in anesthetized rats.In group ALI+BMSCs,1×104 cells/ml BMSCs 0.5 ml (in PBS) was injected via the tail vein after intraperitoneal injection of lipopolysaccharide.PBS 0.5 ml was injected via the tail vein after intraperitoneal injection of lipopolysaccharide in group ALI+PBS.Arterial blood samples were collected at 6,24 and 48 h after injecting BMSCs for blood gas analysis and for determination of wet to dry weight ratio (W/D ratio),pathological changes (using haematoxylin and eosin staining),and expression of TGF-β1,Smad2 and Smad3 in lung tissues (by Western blot).Results Compared with group C,PaO2 was significantly decreased,PaCO2 and W/D ratio were increased,the expression of TGF-β1,Smad2 and Smad3 in lung tissues was up-regulated (P<0.05),and the pathological changes of lung tissues were accentuated in ALI,ALI+BMSCs and ALI+PBS groups.Compared with group ALI,PaO2 was significantly increased,PaCO2and W/D ratio were decreased,the expression of TGF-β1,Smad2 and Smad3 in lung tissues was down-regulated (P<0.05),and the pathological changes of lung tissues were significantly reduced in group ALI+BMSCs.Conclusion The mechanism by which BMSCs mitigates ALI may be associated with inhibiting TGF-β1/Smad signaling pathway in rats.

4.
Chinese Journal of Anesthesiology ; (12): 484-488, 2018.
Artículo en Chino | WPRIM | ID: wpr-709794

RESUMEN

Objective To evaluate the effect of bone marrow-derived mesenchymal stem cells (BMSCs) on mammalian target of rapamycin (mTOR) signaling pathways in lung tissues of rats with acute lung injury (ALI).Methods Healthy pathogen-free adult male Sprague-Dawley rats were selected,and the BMSCs were obtained and cultured in vitro.One hundred and five healthy clean adult male SpragueDawley rats,weighing 170-190 g,were divided into 5 groups (n=21 each) using a random number table:control group (group C),PBS group,group ALI,ALI plus BMSC group (group ALI+BMSCs),and ALI plus phosphate buffer solution (PBS) group (group ALI+PBS).Group C received no treatment.PBS 0.5 ml was injected via the tail vein in group PBS.Lipopolysaccharide (LPS,0.5 ml) 5 mg/kg was intraperitoneally injected to establish the model of ALI in group ALI.BMSCs (0.5 ml) 1×104 cells/ml were injected via the tail vein after intraperitoneal injection of LPS in group ALI+ BMSCs.PBS 0.5 ml was injected via the tail vein after intraperitoneal injection of LPS in group ALI+PBS.Arterial blood samples were collected for blood gas analysis at 6,24 and 48 h after injection of BMSCs.Lungs were then removed for determination of wet/dry weight ratio (W/D ratio) and expression of mTOR,nuclear factor kappa B (NF-κB) and tumor necrosis factor-alpha (TNF-o) in lung tissues (by Western blot) and for examination of the pathologic changes of lungs tissues (using haematoxylin and eosin staining).Results Compared with group C,pH value and PaO2 were significantly decreased,PaCO2 and W/D ratio were increased,and the expression of mTOR,NF-κB and TNF-α was up-regulated at each time point in ALI,ALI+BMSCs and ALI+PBS groups (P<0.05).Compared with group ALI,pH value and PaO2 were significantly increased,PaCO2 and W/D ratio were decreased,the expression of mTOR,NF-κB and TNF-α was down-regulated at each time point (P<0.05),and the pathologic changes of lungs tissues were significantly attenuated in group ALI+BMSCs.Conclusion The mechanism by which BMSCs reduce ALI may be associated with inhibiting mTOR signaling pathways in lung tissues of rats.

5.
Chinese Journal of Anesthesiology ; (12): 563-565, 2014.
Artículo en Chino | WPRIM | ID: wpr-455698

RESUMEN

Objective To evaluate the role of spinal neuronal extracellular signal-regulated protein kinases 5/cAMP response element binding protein (ERK5/CREB) signaling pathway in withdrawal responses in morphinedependent rats.Methods Ninety-six adult male Sprague-Dawley rats in which intrathecal catheters were successfully placed,weighing 200-250 g,were randomly divided into 4 groups (n =24 each):normal control group (group A),morphine withdrawal group (group B),dimethyl sulfoxide (DMSO) + morphine withdrawal group (group C) and ERK5 inhibitor BIX02188 + morphine withdrawal group (group D).Morphine dependence (MD) was induced by increasing doses of subcutaneous morphine for 6 days.The initial dose of morphine was 10 mg/kg once a day and was increased by 10 mg/kg once a day from 2nd to 5th days until 50 mg/kg on 6th day in B,C and D groups.Morphine withdrawal response (MW) was induced by intraperitoneal naloxone 4 mg/kg at 4 h after last morphine administration in B,C and D groups.In addition,BIX02188 10 μg and 1% DMSO 10 μl were injected intrathecally at 1 h before naloxone injection in D and C groups,respectively.MW and morphine withdrawal-induced hyperalgesia were scored.The rats were then sacrificed after hyperalgesia was scored and the spinal cord was removed for determination of CREB and phosphorylated CREB (p-CREB) expression.Results Compared with group A,MW and hyperalgesia scores were significantly increased and the expression of p-CREB was up-regulated in B,C and D groups.Compared with group B,MW and hyperalgesia scores were significantly decreased and the expression of p-CREB was down-regulated in D group,and no significant change was found in group C.Conclusion The spinal neuronal ERK5/CREB signaling pathway is involved in withdrawal responses in morphine-dependent rats.

6.
Chinese Journal of Behavioral Medicine and Brain Science ; (12): 577-579, 2014.
Artículo en Chino | WPRIM | ID: wpr-455531

RESUMEN

Objective To investigate the roles of spinal N-methyl-D-aspartic acid receptor-extracellular signal-regulated protein kinases 5 signaling pathway in naloxone-induced withdrawal response in morphine-dependent rats.Methods Ninety-six adult male SD rats weighting 230-250 g were randomly divided into 4 groups:control group,withdrawal group,DMSO group and MK801 group.Rats were subcutaneously injected with morphine.On day 6,rats were injected with naloxone (intraperitoneal) to precipitate morphine withdrawal syndromes.To identify the function of NMDAR-ERK5 signaling pathway in morphine withdrawal,morphine withdrawal-like behavior test and western blot technique were used in this research.The scores of morphine withdrawal symptom,morphine withdrawal-induced allodynia and the activation of ERK5 in spinal cord were observed after intrathecal injection of MK801.Results There was no withdrawal symptoms and withdrawal-induced allodynia in group A after intraperitoneal injection of naloxone.Compared with group A,withdrawal score (45.2±7.3),score of withdrawal-induced allodynia (14.4±3.7) of group B,withdrawal score (44.7±6.2),score of withdrawal-induced allodynia (13.2±2.7) of group C and withdrawal score (28.3±1.6),score of withdrawal-induced allodynia (5.9± 1.1) of group D were significantly increased (P< 0.05).Compared with group C,the total withdrawal score (28.3 ± 1.6),score of withdrawal-induced allodynia (5.9± 1.1) of group D were significantly decreased (P<0.05).Compared with group A,the expression of spinal p-ERK5 of group B (12848±621) and group C (12579±396) were significantly increased (P<0.05).Compared with group C,the expression of spinal p-ERK5 of group D (5 123±546) was significantly decreased (P<0.05).Condusion The signaling pathway of spinal N-methyl-D-aspartic acid receptor-extracellular signal-regulated protein kinases 5 contributes to naloxone-induced withdrawal response in morphine-dependent rats.

7.
Chinese Journal of Anesthesiology ; (12): 409-411, 2014.
Artículo en Chino | WPRIM | ID: wpr-450280

RESUMEN

Objective To evaluate the efficacy of intra-articular dexmedetomidine mixed with ropivacaine for postoperative analgesia after arthroscopic knee surgery.Methods Sixty ASA physical status Ⅰ or Ⅱ patients,aged 20-64 yr,weighing 50-90 kg,with body height 160-180cm,scheduled for elective arthroscopic knee surgery,were randomly assigned into 2 equal groups using a random number table:ropivacaine group (group R) and dexmedetomidine mixed with ropivacaine group (group RD).In group R,the mixture of noraml saline 1 ml and 19 ml of 0.25% ropivacaine was injected intra-articularly at the end of surgery.In group RD,the mixture of dexmedetomidine 1 μg/kg and 19 ml of 0.25% ropivacaine was injected intra-articularly at the end of surgery.VAS scores at rest and during activity were observed and recorded at 1,2,4,8,12,20 and 24 h after surgery.The duration of analgesia after sugery (from the time immediately after intra-articular administration to the time of first administration of fentanyl as an adjunct to analgesia) and consumption of fentanyl at 24 h after surgery were recorded.Results Compared with group R,VAS scores were significantly decreased at 1,2,4 and 8 h after surgery,the duration of analgesia after sugery was prolonged,and the consumption of fentanyl at 24 h after surgery was reduced in group RD (P < 0.05 or 0.01).There was no significant difference in VAS scores at 12-24 h after surgery between the two groups (P > 0.05).Conclusion Intra-articular dexmedetomidine can significantly improve the efficacy of ropivacaine for postoperative analgesia after arthroscopic knee surgery.

8.
Chinese Journal of Anesthesiology ; (12): 171-173, 2014.
Artículo en Chino | WPRIM | ID: wpr-446824

RESUMEN

Objective To evaluate the changes in the activity of extracellular signal-regulated kinase 5 (ERK5) in the distal cerebrospinal fluid contacting neurons (CSF-CNs) in the mid-brain of morphine dependent rats.Methods Forty-eight male adult Sprague-Dawley rats weighing 230-270 g,were randomly divided into 2 groups (n =24 each) using a random number table:control group (group A) and morphine dependence group (group B).Morphine dependence was induced by increasing doses of subautaneous morphine for 5 consecutive days.The initial dose of morphine was 10 mg/kg twice a day and was increased by 10 mg/kg everyday until 50 mg/kg on 5th dav.The equal volume of normal saline was injected subcutaneously instead of morphine in group A.On 3rd day after morphine dependence was induced,the distal CSF-CNs in the mid-brain was labeled with 30% cholera toxin subunit B and horseradish peroxidase compound (CB-HRP) 3 μl injected in the lateral cerebral ventricle in the morning.At 4 h after the last injection of morphine,the segments in which CSF-CNs were located were removed,and CB-HRP positive neurons,phosphor-ERK5 (p-ERK5) positive neurons and CB-HRP/p-ERK5 positive neurons were counted.Results Compared with group A,the number of p-ERK5 and CB-HRP/p-ERK5 positive neurons in the mid-brain was significantly increased (P < 0.05),and no significant change was found in CB-HRP positive neurons in group B (P > 0.05).Conclusion The enhanced activity of ERK5 in the distal CSFCNs in the mid-brain may contribute to the development of morphine dependence in rats.

9.
Chinese Journal of Behavioral Medicine and Brain Science ; (12): 1057-1059, 2013.
Artículo en Chino | WPRIM | ID: wpr-443100

RESUMEN

Objective To investigate the roles of spinal extracellular signal-regulated protein kinases 5 (ERK5) on morphine withdrawal in rats.Methods Ninety-six male and adult SD rats weighting 230-250 g were randomly divided into saline-naloxone-DMSO group (group A),saline-naloxone-BIX02188 group (group B),morphine-naloxone-DMSO group (group C) and morphine-naloxone-BIX02188 group (group D).To set up morphine dependent model,rats were subcutaneously injected with morphine in the increasing dosage method.On day 6,4 h after the injection of morphine,rats were injected with naloxone (intraperitoneal) to precipitate morphine withdrawal syndrome.The scores of morphine withdrawal symptom and morphine withdrawal-induced allodynia were observed after intrathecal injection of ERK5 inhibitor BIX02188.Result There were not withdrawal symptoms and withdrawal-induced allodynia in group A and B after intraperitoneal injection of naloxone.Compared with group A,teeth chatting (7.5± 1.1),wet dog shacks (4.6± 0.7),jump (5.3± 0.7),abnormal position (8.9± 1.9),diarrhea (7.1 ± 1.6),salivation (2.8±0.6),weight loss (7.9±0.9),total withdrawal score (44.8±5.9),score of withdrawalinduced allodynia (14.6±2.4) of group C and teeth chatting (3.1±0.5),wet dog shacks (1.5±0.4),jump (2.2± 0.5),abnormal position (7.9± 1.6),diarrhea (1.8±0.5),salivation (2.8±0.9),weight loss (3.7±0.6),total withdrawal score (23.1± 1.3) and score of withdrawal-induced allodynia (3.5± 1.1) of group D were significantly increased (P<0.05).Compared with group C,teeth chatting (3.1±0.5),wet dog shacks (1.5±0.4),jump (2.2±0.5),diarrhea (1.8±0.5),weigbt loss (3.7±0.6) and total withdirawal score (23.1±1.3),score of withdrawal-induced allodynia (3.5±1.1) of group D were significantly decreased (P<0.05).But there was not significant change in abnoral position (7.9±1.6) and salivation (2.8±0.9).Conclusion Inhibition of the activation of spinal cord ERK5 can significantly alleviate withdrawal symptoms of morphine dependent rats by intrathecal injection BIX02188.

10.
Chinese Journal of Anesthesiology ; (12): 1212-1214, 2013.
Artículo en Chino | WPRIM | ID: wpr-440391

RESUMEN

Objective To evaluate the role of extracellular signal-regulated protein kinase 5 (ERK5) in the spinal cord in withdrawal responses in morphine-dependent rats.Methods Ninety-six adult male SpragueDawley rats in which intrathecal catheters were successfully placed,weighing 200-250 g,were randomly divided into 4 groups (n =24 each) using a random number table:normal saline group (group A),withdrawal group (group B),dimethyl sulfoxide (DMSO) group (group C) and ERK5 inhibitor BIX02188 group (group D).Morphine dependence (MD) was induced by increasing doses of subcutaneous morphine for 6 days.The initial dose of morphine was 10 mg/kg once a day and was increased by 10 mg/kg once a day from the 2nd to 5th days until 50 mg/kg on the 6th day in B,C and D groups.Morphine withdrawal response (MW) was induced by intraperitoneal naloxone 4 mg/kg at 4 h after last morphine administration in B,C and D groups.In addition,BIX02188 and 1% DMSO 10 μl were injected intrathecally at 1 h before naloxone injection in D and C groups,respectively.MW and morphine withdrawal-induced hypemlgesia were scored.The rats were then sacrificed after hyperalgesia was scored and the spinal cord was removed for determination of ERK5 and phosphorylated ERK5 (p-ERK5) expression.Results Compared with group A,MW and hyperalgesia scores were significantly increased and the expression of pERK5 was up-regulated in B,C and D groups (P < 0.05).Compared with group B,MW and hyperalgesia scores were significantly decreased and the expression of p-ERK5 was down-regulated in D group (P < 0.05),and no significant change was found in group C (P > 0.05).Conclusion ERK5 in the spinal cord is involved in withdrawal responses in morphine-dependent rats.

11.
Chinese Journal of Practical Nursing ; (36): 20-21, 2009.
Artículo en Chino | WPRIM | ID: wpr-393050

RESUMEN

rade the unsafe factors, elevate the rescue drug ad-ministration level, improve nursing personnels' working efficiency and quality.

12.
Journal of Peking University(Health Sciences) ; (6)2003.
Artículo en Chino | WPRIM | ID: wpr-679026

RESUMEN

Objective:To study the role of interleukin 9 in the airway inflammation from patients with COPD. Methods: Induced sputum was obtained from 30 COPD patients with stable disease(group A) ,31 asthmatics patients with stable disease(group B) and 15 healthy individuals(group C). IL 9,IL 5 and IL 8 in sputum supernatants were measured by sandwich enzyme linked immunosorbent assay(ELISA) and IL 9 positive expression and quantitative analysis were conducted by Streptavidin peroxidase method and image analysis technology. Results:The levels of IL 9 in group A and B were all significantly higher than those in groups C. IL 9 positive expression mainly located in the cytoplasm of macrophages. The positive rates of IL 9 in group A and B were all significantly higher than that of group C(? 2=20.821, 19.908, P

13.
Journal of Peking University(Health Sciences) ; (6)2003.
Artículo en Chino | WPRIM | ID: wpr-557058

RESUMEN

Objective : To investigate the changes of leukotriene B4 (LTB4) in both the airways and the blood circulation in an animal model of chronic obstructive pulmonary disease (COPD) and the effects of theophylline on LTB4. Methods: Thirty-two male Wistar rats were divided into four groups by random number meter: Group A (normal controls), group B (COPD), group C (smoking+low dose theophylline), and group D (smoking+high dose theophylline ),with 8 rats in each group. Pulmonary functions of the rats were assessed, and pathological changes of airways were scored. Cell counts and cell differentiation in bronchoalveolar lavage fluid (BALF) were also performed. Concentrations of IL-8 and LTB4 in BALF, plasma and lung tissue were measured by enzyme-linked immunosorbent assay (ELISA) and enzyme immunoassay (EIA). Results: LTB4 concentrations in BALF of COPD rats increased significantly as compared with the normal controls, and positively correlated with the percentage of neutrophil and IL-8 in BALF (r=0.794,0.863 ; P=0.007,0.012), and negatively correlated with peak expiratory flow (PEF) (r=-0.718, P=0.028). Positive correlations were also found between levels of LTB4 in BALF and the scores of inflammatory cell infiltration of COPD rats (r=0.836, P=0.036). Treatment with theophylline decreased the percentage of neutrophil and the concentrations of LTB4 in BALF of the COPD rats, attenuated the pathological changes of small airways, such as airway occlusion, goblet-cell metaplasia, inflammatory cell infiltration, and fibrosis and smooth muscle proliferation. The effect was more significant on goblet-cell metaplasia and inflammatory cell infiltration in the high dose group. However theophylline had little effect on PEF. Conclusion: Our results suggest that LTB4 is involved in airway inflammation in COPD. Theophylline is effective in decreasing the levels of LTB4 in BALF of COPD rats, reducing the percentage of neutrophil, and attenuating pathological changes of small airways.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA