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1.
Int J Nurs Sci ; 10(3): 414-421, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37545776

RESUMO

Objectives: The use of 3D video in medical education has not been fully explored. This article aims to review the evidence on 3D video currently presented in the medical education literature, including its impact on curriculum activities, to reference future research in this field. Methods: According to the guidelines of Arksey and O'Malley, the authors used a systematic search strategy (the last search was in December 2022) to search nine literature databases published in English, and only primary studies were included. Two authors independently screened all articles based on the eligibility criteria and performed a thematic analysis of the included literature. Results: Of 1,302 articles identified, 23 were included for insights into how opportunities for 3D video in medical education are created, how they are experienced, and how they influence and manifest behavior demonstrated partial congruency. Three themes were identified: (a) advantages of using 3D video in medical education; (b) the effect of using 3D video in medical education on students' academic achievement and ability; and (c) students' experience of 3D video in medical education. Conclusions: The application of 3D video in medical education has won the support of most students and educators. However, the effect of using 3D video in medical education is still controversial. Medical educators should combine the curriculum's characteristics, the students' learning situation, and the existing educational resources and choose to use them after careful consideration.

2.
Taiwan J Obstet Gynecol ; 61(1): 15-23, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35181028

RESUMO

The presence of intermediate risk factors reduces the predictability of radical hysterectomy, demanding the use of adjuvant therapy for treatment of Early stage cervical cancer (ESCC) patients. Adjuvant radiotherapy (RT) and chemoradiotherapy (CRT) has been widely used with varied efficacy and safety issues. Therefore, the aim of this systematic review and meta-analysis was to update the available evidence and assess the effect of post-surgical adjuvant RT versus adjuvant CRT on survival rate and complications/toxicities in management of ESCC patients with intermediate risk factors. PubMed, EMBASE and Web of Science (WOS) and CENTRAL were searched using a combination of relevant keywords. All studies comparing outcomes of adjuvant RT versus CRT in ESCC patients with intermediate-risk factors in terms of recurrence free survival (RFS), overall survival (OS) and toxicities/complications were included. Both qualitative and quantitative analysis was carried out. The risk of bias assessment was done using Newcastle-Ottawa scale (NOS) for retrospective cohort studies and Cochrane risk of bias assessment tool was used for randomized clinical trials. Eleven retrospective cohort studies and two randomized clinical trials were included in this review. Adjuvant CRT was found to have better RFS with ESCC patients with multiple intermediate risk factors with OR 3.11 95% CI [1.04, 4.99], p < 0.0001; i2 = 6%. However, similar benefit was observed between both regimens in presence of a single intermediate risk factor OR 1.80 95% CI [0.96, 3.36], p = 0.07; i2 = 0%. Grade 3 or 4 haematological toxicity among patients receiving post-surgical adjuvant RT versus adjuvant CRT showed increased association of toxicity with adjuvant CRT with OR 7.73 95%CI [3.40, 17.59], p < 0.0001; i2 = 62%. Adjuvant CRT shows favourable RFS and OS in ESCC patients with multiple intermediate risk factors. CRT also showed greater incidence of grade 3 or 4 haematological and non-haematiological toxicity, however, the same could be well tolerated when used within the recommended dosage.


Assuntos
Quimiorradioterapia Adjuvante , Radioterapia Adjuvante , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/radioterapia , Carcinoma de Células Escamosas/mortalidade , Quimiorradioterapia , Feminino , Humanos , Histerectomia , Estadiamento de Neoplasias , Taxa de Sobrevida , Neoplasias do Colo do Útero/patologia
3.
Medicine (Baltimore) ; 100(32): e26911, 2021 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-34397927

RESUMO

RATIONALE: With the recent advancements in molecular biology research, epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) have emerged as excellent therapies for patients with EGFR-mutant cancers. However, these patients inevitably develop cross-acquired resistance to EGFR-TKIs. Transformation to small-cell lung cancer (SCLC) is considered a rare resistance mechanism against EGFR-TKI therapy. Here, we report a case of TKI resistance due to SCLC transformation and demonstrate its mechanisms and clinical features. PATIENT CONCERNS: A 54-year-old Chinese man with a history of smoking for 40 years complained of an intermittent cough in March 2019. DIAGNOSIS: Transbronchial lung biopsy was performed on the basal segment of the left lower lobe, which confirmed lung adenocarcinoma. In January 2020, repeat biopsy was performed, and the results of immunohistochemistry (IHC) staining showed TTF-1 (+), CK7 (+), napsin A (+), syn (+), and CD56 (+), with a Ki-67 (+) index 80% of small cell carcinomas. Infiltrating adenocarcinomas and small cell carcinomas were observed. INTERVENTIONS: Icotinib (125 mg thrice daily) was administered as a first-line treatment from June 2019. We subsequently administered a chemotherapy regimen consisting of etoposide (180 mg, days 1-3) plus cisplatin (45 mg, days 1-3) every 3 weeks for 1 cycle after recurrence. As the patient could not tolerate further chemotherapy, he continued taking icotinib orally and received whole-brain radiotherapy 10 times to a total dose of 30 Gy after brain metastases. OUTCOMES: The patient relapsed after successful treatment with icotinib for 9 months. A partial response was achieved after 4 cycles of chemotherapy, and despite the brief success of chemotherapy, our patient exhibited brain metastasis and metastases of the eleventh thoracic spine and the second lumbar vertebra with pathological fracture. The patient eventually died of aggressive cancer progression. LESSONS: Our case highlights the possibility of SCLC transformation from EGFR-mutant adenocarcinoma and the importance of repeat biopsy for drug resistance. Serum neuron-specific enolase levels may also be useful for detecting early SCLC transformation.


Assuntos
Adenocarcinoma de Pulmão/genética , DNA de Neoplasias/genética , Neoplasias Pulmonares/genética , Mutação , Carcinoma de Pequenas Células do Pulmão/genética , Adenocarcinoma de Pulmão/metabolismo , Adenocarcinoma de Pulmão/patologia , Biópsia , Transformação Celular Neoplásica , Análise Mutacional de DNA , Receptores ErbB/genética , Receptores ErbB/metabolismo , Evolução Fatal , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/metabolismo , Masculino , Pessoa de Meia-Idade , Carcinoma de Pequenas Células do Pulmão/diagnóstico , Carcinoma de Pequenas Células do Pulmão/metabolismo , Tomografia Computadorizada por Raios X
4.
Medicine (Baltimore) ; 100(10): e24991, 2021 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-33725872

RESUMO

RATIONALE: Crouzon syndrome is an autosomal dominant genetic disorder caused by mutations in fibroblast growth factor receptor 2 (FGFR2) and one of the most common types of craniosynostosis. Here we report the detection of FGFR2 mutation and its related clinical findings in 2 patients with Crouzon syndrome from a Chinese family. PATIENT CONCERNS: We report a case of a 28-year-old male patient presented with the chief complaint of gradually blurring of his eyes over the last 6 months before visiting our clinics. History revealed low visual acuity in his right eye since childhood. Physical examination showed that both the patient and his mother have the appearance of craniofacial dysostosis, mandibular prognathism, ocular proptosis, short superior lip, scoliosis, and thoracic deformity. DIAGNOSIS: Auxiliary examinations lead to the diagnosis of Crouzon syndrome with binocular optic atrophy, myelinated retina nerve fibers, and ametropia in both eyes, and amblyopia in the right eye of the male patient. The molecular genetic analysis confirmed the diagnosis by detecting a heterozygous pathogenic mutation c.1026C > G (C342W) in exon 10 of FGFR2 in both the patient and his mother, but not in any of the unaffected family members. INTERVENTIONS AND OUTCOMES: None. LESSONS: Our study confirms the presence of optic nerve atrophy in patients with Crouzon syndrome carrying FGFR2 C342W mutations and indicates that MRI and funduscopy should be performed to examine the optic nerve changes for patients with Crouzon syndrome.


Assuntos
Disostose Craniofacial/complicações , Atrofias Ópticas Hereditárias/genética , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/genética , Adulto , China , Disostose Craniofacial/genética , Análise Mutacional de DNA , Éxons/genética , Feminino , Angiofluoresceinografia , Heterozigoto , Humanos , Imageamento por Ressonância Magnética , Masculino , Mutação de Sentido Incorreto , Atrofias Ópticas Hereditárias/diagnóstico , Nervo Óptico/diagnóstico por imagem , Linhagem , Tomografia Computadorizada por Raios X
5.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 46(4): 349-356, 2017 Jul 25.
Artigo em Chinês | MEDLINE | ID: mdl-29256222

RESUMO

OBJECTIVE: To investigate the effects of microRNA(miRNA)-29b on the proliferation and migration of breast cancer cells and its molecular mechanism. METHODS: The recombinant lentiviral expression vector (lenti-miRNA-29b) was constructed and transfected into 293T cells to obtain lentivirus particles that were used to infect breast cancer MCF-7 cells. Transfection efficiency of lenti-miRNA-29b in MCF-7 cells was identified by the expression of green fluorescent protein (GFP). The expression of miRNA-29b was detected by real-time PCR. The cell proliferation and migration were detected by CCK8 assay and Transwell assay, respectively. The bioinformatics softwares were used to predict and screen the downstream target genes regulated by miRNA-29b, which were verified by double luciferase reporter gene assay, RT-PCR and Western blot. The effects of screened target gene RTKN on the growth and migration of MCF-7 cells were verified by RTKN siRNA. RESULTS: Recombinant lentiviral expression vector of miRNA-29b were successfully constructed. About 90% and 60% of the breast cancer cells showed green fluorescence in lenti-miRNA-29b and lenti-miRNA-NC groups, respectively. The expression of miRNA-29b in lenti-miRNA-29b group increased significantly compared with the lenti-miRNA-NC group and blank control group (all P<0.05); the proliferation and migration ability of MCF-7 cells significantly reduced compared with the control group (all P<0.05). The screening with bioinformatics softwares found that the 3'UTR coding region RTKN had the binding site to miRNA-29b; the dual luciferase reporter gene assay showed that the luciferase activity decreased significantly after the MCF-7 cells were co-transfected with wild type RTKN-WT-3'UTR and miRNA-29b mimics report gene vector (P<0.05). The RTKN proteins in MCF-7 cells were significantly decreased after transfection with siRNA-RTKN, and the proliferation and migration ability of MCF-7 cells were significantly reduced (all P<0.05). CONCLUSIONS: MiRNA-29b can inhibit the proliferation, invasion and metastasis of breast cancer cells by inhibiting the expression of RTKN.


Assuntos
Movimento Celular , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , MicroRNAs , Neoplasias da Mama , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Técnicas In Vitro , Células MCF-7 , MicroRNAs/genética , MicroRNAs/farmacologia
6.
Int J Clin Exp Med ; 8(1): 1482-6, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25785159

RESUMO

We reported a 9-year-old boy with mycoplasma pneumonia who developed pulmonary infarction. The child first had fever and cough, and then had difficult breathing. But, the signs of his lung were not obvious. Mycoplasma antibody IgM was positive. The child was given intravenous azithromycin for anti-infection, and intravenous low molecular weight heparin and oral warfarin for anti-coagulation. Although difficult breathing was relieved, sudden cardiac arrest occurred. His parents requested to give up treatment.

7.
Brain Res ; 1359: 247-55, 2010 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-20813100

RESUMO

Fibrates are activators of peroxisome proliferator-activated receptor (PPAR) α. Pretreatment with fibrates has been shown to protect brain against ischemia in mice. We hypothesized that fibrates elevate superoxide dismutase (SOD) levels in the brain microvessels (BMVs). BMVs were isolated from male C57BL/6 and PPARα null mice that had been treated with fenofibrate or gemfibrozil for 7 days. To examine the effect of discontinuation of fenofibrate, another animal group treated with fenofibrate was examined on post-discontinuation day 3 (D-3). To examine whether SOD elevations attenuate oxidative stress in the ischemic brain, separate animals treated with fenofibrate for 7 days were subjected to 60 minutes of focal ischemia on post-discontinuation day 0 (D-0) or D-3. Fenofibrate (30 mg/kg) increased mRNA levels of all three isoforms of SOD and activity level in BMV on D-0, but these effects were not detected on D-3. The elevations were not detected in PPARα null mice. SOD levels were also elevated by gemfibrozil (30 mg/kg). Fenofibrate significantly reduced superoxide production and protein oxidation in the ischemic brain at 30 minutes after reperfusion. Fenofibrate reduced infarct size measured at 24 hours after reperfusion on D-0; however, the infarct reduction was not seen when ischemia was induced on D-3. These findings suggest that fibrates elevate SOD in BMV through PPARα, which contributes to the infarct reduction, at least in part. Further studies are needed to establish the link between the SOD elevations and the brain protection by fibrates against ischemia.


Assuntos
Encéfalo/efeitos dos fármacos , Fenofibrato/farmacologia , Genfibrozila/farmacologia , Microvasos/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Superóxido Dismutase/biossíntese , Animais , Encéfalo/enzimologia , Encéfalo/fisiopatologia , Isquemia Encefálica/fisiopatologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microvasos/enzimologia , Microvasos/patologia , Estresse Oxidativo/efeitos dos fármacos , PPAR gama/metabolismo , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa
8.
J Cereb Blood Flow Metab ; 30(1): 70-8, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19724288

RESUMO

Fibrates, one group of peroxisome proliferator-activated receptor (PPAR) activators, are lipid lowering drugs. Fibrates have been shown to attenuate brain tissue injury after focal cerebral ischemia. In this study, we investigated the impact of fenofibrate on cerebral blood flow (CBF) in male wild type and PPARalpha-null mice. Animals were treated for 7 days with fenofibrate and subjected to 2 h of filamentous middle cerebral artery occlusion and reperfusion under isoflurane anesthesia. Cortical surface CBF was measured by laser speckle imaging. Regional CBF (rCBF) in nonischemic animals was measured by (14)C-iodoantipyrine autoradiography. Fenofibrate did not affect rCBF and mean arterial blood pressure in nonischemic animals. In ischemic animals, laser speckle imaging showed delayed expansions of ischemic area, which was attenuated by fenofibrate. Fenofibrate also enhanced CBF recovery after reperfusion. However, such effects of fenofibrate on CBF in the ischemic brain were not observed in PPARalpha-null mice. These findings show that fenofibrate improves CBF in the ischemic hemisphere. Moreover, fenofibrate requires PPARalpha expression for the cerebrovascular protective effects in the ischemic brain.


Assuntos
Circulação Cerebrovascular/efeitos dos fármacos , Fenofibrato/farmacologia , Hipolipemiantes/farmacologia , Artéria Cerebral Média/fisiologia , Animais , Antipirina/análogos & derivados , Arteriopatias Oclusivas/fisiopatologia , Autorradiografia , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/patologia , Capilares/efeitos dos fármacos , Capilares/patologia , Infarto Cerebral/patologia , Colesterol/sangue , Expressão Gênica/fisiologia , Masculino , Camundongos , Óxido Nítrico Sintase Tipo III/biossíntese , Óxido Nítrico Sintase Tipo III/genética , PPAR alfa/biossíntese , PPAR alfa/genética , PPAR alfa/fisiologia , RNA/biossíntese , RNA/genética , Compostos Radiofarmacêuticos , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Triglicerídeos/sangue
9.
Brain Res ; 1294: 183-92, 2009 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-19646426

RESUMO

Matrix metalloproteinase (MMP)-9 has been shown to contribute to blood-brain barrier (BBB) disruption, infarct formation, and hemorrhagic transformation after ischemic stroke. The cellular source of MMP-9 detectable in the ischemic brain remains controversial since extracellular molecules in the brain may be derived from blood. We here demonstrate that bone marrow-derived cells are the major source of MMP-9 in the ischemic brain. We made bone marrow chimeric mice with MMP-9 null and wild-type as donor and recipient. After 90 min of transient focal cerebral ischemia, MMP-9 null mice receiving wild-type bone marrow showed comparable outcomes to wild-type in brain MMP-9 levels and BBB disruption (endogenous albumin extravasation) at 1 h post-reperfusion and infarct size at 24 h post-reperfusion. In contrast, wild-type animals replaced with MMP-9 null bone marrow showed barely detectable levels of MMP-9 in the ischemic brain, with attenuations in BBB disruption and infarct size. MMP-9 null mice receiving wild-type bone marrow showed enhanced Evans blue extravasation as early as 1 h post-reperfusion compared to wild-type mice replaced with MMP-9 null bone marrow. These findings suggest that MMP-9 released from bone marrow-derived cells influences the progression of BBB disruption in the ischemic brain.


Assuntos
Barreira Hematoencefálica/fisiopatologia , Células da Medula Óssea/fisiologia , Infarto Encefálico/fisiopatologia , Isquemia Encefálica/fisiopatologia , Metaloproteinase 9 da Matriz/metabolismo , Acidente Vascular Cerebral/fisiopatologia , Animais , Animais Geneticamente Modificados , Barreira Hematoencefálica/patologia , Transplante de Medula Óssea , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Encéfalo/fisiopatologia , Infarto Encefálico/patologia , Isquemia Encefálica/patologia , Permeabilidade Capilar , Gelatinases/metabolismo , Masculino , Metaloproteinase 9 da Matriz/genética , Camundongos , Acidente Vascular Cerebral/patologia , Fatores de Tempo , Quimeras de Transplante
10.
Brain Res ; 1279: 121-30, 2009 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-19427843

RESUMO

Fibrates are lipid lowering drugs and found as ligands for peroxisome proliferator-activated receptors (PPARs). A clinical study has shown that one type of fibrate gemfibrozil reduces stroke incidence in men. However, it remains unknown whether gemfibrozil improves outcome after stroke. We hypothesized that prophylactic administration of gemfibrozil improves outcome after ischemic stroke. In this study, we measured the impact of gemfibrozil in two permanent middle cerebral artery occlusion (MCAO) models in young adult male mice on normal diet. First, we tested gemfibrozil in a filamentous MCAO model. Pretreatment with gemfibrozil (30 mg/kg) for 7 days moderately but significantly reduced infarct size at 24 h after MCAO. A higher dose (120 mg/kg) did not attenuate infarct size. Rather, it tended to increase brain swelling. Second, we tested in a distal MCAO model. Gemfibrozil (30 mg/kg) for 7 days before and after stroke significantly attenuated cortical lesion size at 7 days after MCAO. Cortical blood flow measured by laser speckle imaging was improved by gemfibrozil in the ischemic hemisphere. In non-stroke animals gemfibrozil also altered gene expression levels of PPARs in both the aorta and brain in organ specific manners; however, endothelial nitric oxide synthase (eNOS) was not significantly affected. These findings suggested the possibility that the observed infarct reductions and cortical blood flow improvements in ischemic brains were not through eNOS-mediated mechanisms. Further investigations may be meritorious to examine whether prophylactic usage of gemfibrozil against stroke is beneficial.


Assuntos
Genfibrozila/administração & dosagem , Hipolipemiantes/administração & dosagem , Infarto da Artéria Cerebral Média/tratamento farmacológico , Animais , Aorta/metabolismo , Temperatura Corporal/efeitos dos fármacos , Encéfalo/irrigação sanguínea , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Circulação Cerebrovascular/efeitos dos fármacos , Colesterol/metabolismo , Genfibrozila/química , Expressão Gênica/efeitos dos fármacos , Hipolipemiantes/química , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Óxido Nítrico Sintase Tipo III/metabolismo , Receptores Ativados por Proliferador de Peroxissomo/genética , Receptores Ativados por Proliferador de Peroxissomo/metabolismo , RNA Mensageiro/metabolismo , Índice de Gravidade de Doença , Resultado do Tratamento , Triglicerídeos/metabolismo
11.
Stroke ; 39(7): 2099-104, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18436885

RESUMO

BACKGROUND AND PURPOSE: Filamentous middle cerebral artery occlusion (fMCAO) is the most frequently used focal cerebral ischemia model in rodents. The proximity of the ophthalmic artery to the middle cerebral artery suggests that fMCAO induces retinal ischemia. We therefore tested whether fMCAO induces ischemia/reperfusion damage in retina in mice. METHODS: SV129EV mice were subjected to transient (30 or 60 minutes) fMCAO followed by reperfusion under isoflurane anesthesia. Retinal perfusion was evaluated by intravenous injection of fluorescent microspheres combined with fluorescent microscopy using flat-mounted retinas. The fluorescent density of ipsilateral retina relative to contralateral retina was determined in each animal. Retinal injury was assessed by cresyl violet staining and in situ TUNEL. RESULTS: Microsphere analysis demonstrated perfusion defect in the ipsilateral retina after 60 minutes fMCAO and effective restoration after reperfusion. Thirty minutes fMCAO did not produce evident histological changes, even after 2 days of reperfusion. Sixty minutes fMCAO followed by 2 hours reperfusion resulted in extensive cell damage in the inner nuclear (>30%) and ganglion cell (>50%) layers. TUNEL demonstrated very few positive cells, suggesting that damaged cells were mainly undergoing nonapoptotic cell death. CONCLUSIONS: Sixty minutes fMCAO produces retinal injury in SV129EV mice. Potential visual dysfunction should be considered when a particular occlusion period is selected for studying neurological outcomes after fMCAO. Because visual disturbance is often associated with thrombotic/embolic stroke in humans, fMCAO represents an appropriate model for future studies aimed at understanding and ameliorating the changes that lead to retinal damage in these patients.


Assuntos
Infarto da Artéria Cerebral Média/complicações , Isquemia/patologia , Retina/patologia , Amaurose Fugaz , Animais , Apoptose , Marcação In Situ das Extremidades Cortadas , Infarto da Artéria Cerebral Média/patologia , Isoflurano/farmacologia , Masculino , Camundongos , Microscopia de Fluorescência , Microesferas , Modelos Anatômicos , Consumo de Oxigênio , Traumatismo por Reperfusão
12.
Ann Emerg Med ; 47(4): 381-9, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16546625

RESUMO

STUDY OBJECTIVE: We compare the effects of postinjury administration of allopregnanolone, a metabolite of progesterone, to progesterone in an animal model of transient middle cerebral artery occlusion. METHODS: Focal cerebral ischemia was induced in age-matched, adult, male, Sprague-Dawley rats by using an intraluminal filament and suture method to occlude the right middle cerebral artery. After 120 minutes of middle cerebral artery occlusion, the occluding filament was withdrawn to allow reperfusion. Laser-Doppler flowmetry was used to monitor cerebral blood flow for the entire 2-hour period of occlusion and for 5 minutes after reperfusion. Animals subjected to middle cerebral artery occlusion received injections of allopregnanolone (8 mg/kg, n=6), progesterone (8 mg/kg, n=6) and vehicle (2-hydroxypropyl-beta-cyclodextrin, n=7) at 2 hours (intraperitoneally 5 minutes before reperfusion) and 6 hours (subcutaneously) postocclusion. Brains were removed at 72 hours post-middle cerebral artery occlusion, sectioned into coronal slices, and stained with 2,3,5-triphenyltetrazolium chloride (TTC). In a blinded analysis, infarct volume was calculated by using computer-aided morphometry to measure brain areas not stained with TTC. RESULTS: After progesterone or allopregnanolone treatment, stained sections revealed a significant reduction in cortical, caudate-putamen, and hemispheric infarct volumes (percentage of contralateral structure) compared with vehicle-injected controls. Cortical infarction (percentage of contralateral cortex) was 37.47%+/-10.57% (vehicle), 25.49%+/-7.38% (progesterone; P<.05 from vehicle), and 11.40%+/-7.09% (allopregnanolone; P<.05 from vehicle; P<.05 from progesterone). Caudate-putamen infarction (percentage of contralateral caudate-putamen) was 78.02%+/-22.81% (vehicle), 48.41%+/-22.44% (progesterone; P<.05 from vehicle), and 50.44%+/-10.90% (allopregnanolone; P<.05 from vehicle). Total hemispheric infarction (percentage of contralateral hemisphere) was 24.37%+/-6.69% (vehicle), 15.95%+/-3.59% (progesterone; P<.05 from vehicle), and 11.54%+/-3.71% (allopregnanolone; P<.05 from vehicle). No significant differences in cerebral blood flow between groups and time points during ischemia and early reperfusion were observed, suggesting that the relative ischemic insult was equivalent among all groups. CONCLUSION: Although progesterone and allopregnanolone are effective in reducing infarct pathology, allopregnanolone is more potent than progesterone in attenuating cortical damage. Our results suggest that both neurosteroids should be examined for safety and efficacy in a clinical trial for ischemic stroke.


Assuntos
Infarto da Artéria Cerebral Média/tratamento farmacológico , Pregnanolona/uso terapêutico , Progesterona/uso terapêutico , Análise de Variância , Animais , Autopsia , Encéfalo/patologia , Circulação Cerebrovascular , Interpretação Estatística de Dados , Modelos Animais de Doenças , Infarto da Artéria Cerebral Média/patologia , Infarto da Artéria Cerebral Média/fisiopatologia , Injeções Intraperitoneais , Injeções Subcutâneas , Fluxometria por Laser-Doppler , Masculino , Pregnanolona/administração & dosagem , Progesterona/administração & dosagem , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão , Fatores de Tempo
13.
Exp Neurol ; 198(2): 469-78, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16445913

RESUMO

This study investigates whether progesterone administration regulates AQP4 and GFAP expression in rats with bilateral contusion injuries of the medial frontal cortex. Male rats were given 0 or 16 mg/kg injections of progesterone at 1, 6, 24, and 48 h post-injury. Brains were extracted at 24 h or 72 h post-injury and assayed for cerebral edema and AQP4 and GFAP expression using Western blot analysis. Progesterone treatments reduced brain water content significantly in the brain-injured groups. There was no significant change in AQP4 expression 24 h after progesterone treatment compared to lesion + vehicle animals. However, progesterone significantly reduced AQP4 expression at 72 h post-injury in the tissue bounded by the lateral ventricles and the peri-contusion areas compared to lesion+ vehicle rats, but increased AQP4 expression in the tissue surrounding the third ventricle. Also progesterone effects on GFAP expression varied according to brain region. Our results can be taken to show that the expression of AQP4 protein after TBI is time-dependent, region-specific, and possibly implicated in the formation and resolution of TBI-induced cerebral edema.


Assuntos
Aquaporina 4/metabolismo , Edema Encefálico/tratamento farmacológico , Lesões Encefálicas/complicações , Regulação da Expressão Gênica/efeitos dos fármacos , Progesterona/administração & dosagem , Análise de Variância , Animais , Western Blotting/métodos , Edema Encefálico/etiologia , Edema Encefálico/patologia , Lesões Encefálicas/patologia , Ventrículos Cerebrais/efeitos dos fármacos , Ventrículos Cerebrais/metabolismo , Ventrículos Cerebrais/patologia , Modelos Animais de Doenças , Imunofluorescência/métodos , Expressão Gênica/efeitos dos fármacos , Proteína Glial Fibrilar Ácida/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Fatores de Tempo , Água/metabolismo
14.
J Neurotrauma ; 22(1): 106-18, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15665606

RESUMO

This report compares the effects of progesterone and its metabolite, allopregnanolone, on the early injury cascade (apoptosis) and long-term functional deficits after TBI. Progesterone (16 mg/kg) or allopregnanolone (4, 8, or 16 mg/kg) were injected at 1 h, 6 h, and then for 5 consecutive days after bilateral contusions of the frontal cortex in adult male rats. Within one day after injury, progesterone and allopregnanolone reduced both the expression of pro-apoptotic proteins caspase-3 and Bax, and apoptotic DNA fragmentation. Progesterone and allopregnanolone also reduced the size of glial fibrillary acid protein (GFAP)-positive astrocytes at the lesion site 24 h after injury. Compared to sham-operated controls at 19 days after injury, injured rats given either progesterone or any of three doses of allopregnanolone had equivalent numbers of ChAT-positive cells in the nucleus basalis magnocellularis. At 19 days post-injury, rats given progesterone or allopregnanolone (8 mg/kg) showed improved performance in a spatial learning task compared to injured rats given only the vehicle. These results provide evidence of the anti-apoptotic and anti-astrogliotic effects of progesterone and allopregnanolone and help to explain why better cognitive performance is observed after injury when animals are given either neurosteroid.


Assuntos
Apoptose/efeitos dos fármacos , Lesões Encefálicas/metabolismo , Fármacos Neuroprotetores/farmacologia , Pregnanolona/farmacologia , Progesterona/farmacologia , Animais , Astrócitos/efeitos dos fármacos , Lesões Encefálicas/complicações , Lesões Encefálicas/fisiopatologia , Caspase 3 , Caspases/efeitos dos fármacos , Caspases/metabolismo , Fragmentação do DNA/efeitos dos fármacos , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Proteínas Serina-Treonina Quinases/efeitos dos fármacos , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas/efeitos dos fármacos , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-akt , Proteínas Proto-Oncogênicas c-bcl-2/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos , Ratos Sprague-Dawley , Fatores de Tempo , Proteína X Associada a bcl-2
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