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1.
EPJ Data Sci ; 11(1): 35, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35694703

RESUMO

This study examined how the knowledge market promotes knowledge construction on question-and-answer (Q&A) websites. Data were collected from Zhihu, one of the largest Q&A sites in China. Hierarchical linear modeling was employed to estimate the dynamics of information accumulation, that is, the provision of informative content as factual construction. By employing information accumulation as the objective measure of knowledge construction, we determined that online knowledge construction was facilitated by a competitive marketplace of ideas. In addition, participation, temporal, and discourse features affected the dynamics of information accumulation. In specific, active users contributed significantly less to information accumulation than did ordinary users. Information accumulation shows a naturally decaying process represented as a function of answer order. The time interval between answers at the two preceding time points reduced the informativeness of answers at the subsequent time point. Answers with a higher readability score reduced the informativeness of subsequent answers. The results indicate that knowledge construction on Q&A sites unfolds as a process of mass collaboration among users. Supplementary Information: The online version contains supplementary material available at 10.1140/epjds/s13688-022-00346-6.

2.
World J Clin Cases ; 8(19): 4512-4520, 2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-33083412

RESUMO

BACKGROUND: Duodenal obstruction is a common clinical scenario that can either be mechanical or a pseudo-obstruction. Clinical management of intestinal obstruction starts from localization and proceeds to histological examination of the stenotic intestine. Systemic factors and dysfunction of distant organs might contribute to the development of intestinal obstruction. Here, we report a unique case of idiopathic mechanical duodenal obstruction, which resolved spontaneously after 3 mo of conservative treatment, but was followed by intestinal pseudo-obstruction. CASE SUMMARY: An 84-year-old woman presented with worsened postprandial vomiting accompanied by prolonged pneumonia. Thorough noninvasive investigations revealed complete circumferential stenosis in the descending duodenum without known cause. Exploratory surgery was postponed due to septic shock and possible pulmonary fungal infection. Conservative treatment for 3 mo for ileus and control of pulmonary infection resolved the intestinal obstruction completely. Unfortunately, 2 wk later, she had regurgitation and postprandial vomiting again, complicated by deteriorating wheezing and dyspnea. Computed tomography revealed a dilated stomach and proximal duodenum without new intestinal stricture or pulmonary infiltration. The patient fully recovered after combined treatment with antireflux agents, enema, prokinetics, and bronchodilators. CONCLUSION: This complicated case highlights the inter-relationship of local and systemic contributions to ileus and gut dysfunction, which requires multidisciplinary treatment.

3.
Ying Yong Sheng Tai Xue Bao ; 30(6): 1956-1964, 2019 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-31257768

RESUMO

The variation of forest canopy structure and understory light caused by natural or human disturbances might account for environmental heterogeneity and species diversity in the understory. These factors play an important role in driving the structure, process and pattern in forest ecosystem. We set up two 0.25 hm2 permanent plots in secondary Betula platyphylla-Populus davidiana forests on the Taoshan Forest Farm, one of which was thinned in 2012 and the other one remained natural. The canopy images of two plots were collected by hemispherical photography technology from 2012 to 2016 and 2018. Analysis of variance and Markov matrix were applied to examine the dynamics of canopy structure, understory light, and canopy closing process after thinning. The results showed that thinning was effective in adjusting canopy structure and understory light availability. Such process lasted for a long time and the adjusting effect decreased over time. After thinning, the change rate of canopy structure and understory light decreased over time. The tree canopy quickly closed during the first three years and then reached a stable state. Understory light availability was positively correlated with canopy openness and negatively correlated with leaf area index. The correlation between understory scattered radiation and canopy structural parameters was the strongest. The correlation between canopy structure and understory light in the thinning plot was stronger than that of the control plot. After thinning, the recovery rate of canopy structure was related to the canopy openness, with larger canopy openness being accompanied with higher recovery rate. Thus, less time was required for the transfer to smaller canopy openness. The Markov matrix model could simulate changes in distributions of canopy structure and could be used to predict the dynamics of the canopy structure.


Assuntos
Betula , Populus , Ecossistema , Agricultura Florestal , Florestas , Árvores
4.
BMC Surg ; 19(1): 3, 2019 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-30616574

RESUMO

BACKGROUND: Intrahepatic subcapsular hematoma (ISH) is an extremely rare, life-threatening complication after laparoscopic cholecystectomy (LC). Only few cases have been reported. Herein, we reported a rare giant ISH after LC and summarized all of the reported cases. CASE PRESENTATION: A 32-year old woman with recurrent acute cholecystitis for one year, underwent elective LC without intra-operative complications and was discharged 2 days after operation. On the next day after discharge, she developed severe right upper abdominal pain and was sent to our emergency department. The computed tomography scan showed a 10.9 × 12.5 × 6.6 cm ISH in the right liver without free fluid and the hemoglobin dropped to 86 g/l from 127 g/l. Postoperative hemorrhagic shock and a giant ISH after LC were diagnosed. After fluid resuscitation, the hemodynamic was still unstable and the hemoglobin kept dropping. An emergency laparoscopic exploration was performed and the ISH was confirmed, however no active bleeding point was found. A drainage tube was placed under liver for early warning of rupture. Patient was discharged home 10 days after readmission. CONCLUSIONS: Giant ISH is an extremely rare, life-threatening complication after LC. This case showed that the need to consider this rare complication in patients suffering abdominal pain after LC and timely and correct diagnosis and treatment were crucial to saving the lives of the patients.


Assuntos
Colecistectomia Laparoscópica/efeitos adversos , Hematoma/etiologia , Hepatopatias/diagnóstico , Adulto , Colecistite Aguda/cirurgia , Drenagem/métodos , Feminino , Humanos , Tomografia Computadorizada por Raios X
5.
Chin J Integr Med ; 24(10): 763-767, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29926388

RESUMO

OBJECTIVE: To investigate the anti-proliferative effects of saponins prepared from Plena Clematis (PC) cultured in Fujian Province, China on 4 human tumor cell lines and its possible anti-tumor mechanism. METHODS: The growth inhibition assays of saponins on human esophageal squamous carcinoma cell line (EC9706), human hepatoma cell line (HepG-2), human oral cancer cell line (KB) and human gastric cancer cell line (BGC-823) were evaluated in vitro by thiazolyl blue (MTT) method. The inhibitory effects on EC9706 treated with different concentrations of saponins (15.62, 31.25, 62.50, 125, 250 and 500 µg/mL) were performed in vitro by MTT method. The morphology and nuclear staining with acridine orange/ethidium bromide of EC9706 cells treated with saponins were illustrated under an inverted phase fluorescence microscope. The apoptotic effects of saponins were further evaluated by annexin-V/propidium iodide dual staining experiment to examine the occurrence of phosphatidylserine externalization onto the cell surface by a flflow cytometer. RESULTS: MTT assay showed that the saponins could inhibit the proliferation of 4 tumor cell lines. Among them, the maximum inhibition rate of 73.1% was detected in EC9706 cells at the saponins concentration of 250 µg/mL for 24 h. Further investigation indicated that the saponins induced EC9706 cells apoposis. The EC9706 cells presented apoptotic characteristics when treated with saponins, including that the morphologies of EC9706 cells were appeared round-shaped with higher refraction, and the cell nuclear stained orange with EB after 250 µg/mL saponins exposure. The flow cytometry analysis results showed that the induction of cell cycle arrest in apoptotic system may participate in the anti-proliferative activity of saponins on EC9706 cells. CONCLUSION: The saponins from PC exhibited significant cytotoxicity against human EC9706, KB, BGC-823, and HepG-2 cells and might be beneficial to development of ethnic pharmaceutical plant for potential anti-tumor drugs.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Clematis , Saponinas/farmacologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Clematis/química , Humanos
6.
Biomed Environ Sci ; 31(3): 197-207, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29673442

RESUMO

OBJECTIVE: To investigate the subchronic oral toxicity of silica nanoparticles (NPs) and silica microparticles (MPs) in rats and to compare the difference in toxicity between two particle sizes. METHODS: Sprague-Dawley rats were randomly divided into seven groups: the control group; the silica NPs low-, middle-, and high-dose groups; and the silica MPs low-, middle-, and high-dose groups [166.7, 500, and 1,500 mg/(kg•bw•day)]. All rats were gavaged daily for 90 days, and deionized water was administered to the control group. Clinical observations were made daily, and body weights and food consumption were determined weekly. Blood samples were collected on day 91 for measurement of hematology and clinical biochemistry. Animals were euthanized for necropsy, and selected organs were weighed and fixed for histological examination. The tissue distribution of silicon in the blood, liver, kidneys, and testis were determined. RESULTS: There were no toxicologically significant changes in mortality, clinical signs, body weight, food consumption, necropsy findings, and organ weights. Differences between the silica groups and the control group in some hematological and clinical biochemical values and histopathological findings were not considered treatment related. The tissue distribution of silicon was comparable across all groups. CONCLUSION: Our study demonstrated that neither silica NPs nor silica MPs induced toxicological effects after subchronic oral exposure in rats.


Assuntos
Nanopartículas/toxicidade , Dióxido de Silício/toxicidade , Administração Oral , Animais , Relação Dose-Resposta a Droga , Feminino , Masculino , Tamanho da Partícula , Ratos , Ratos Sprague-Dawley , Testes de Toxicidade Subcrônica
8.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 36(6): 680-5, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25556746

RESUMO

Acute spinal cord injury(ASCI),mainly caused by traffic accidents and fall injuries,is a catastrophic event that can profoundly affect the trajectory of a patient's life. Debate continues over the medical management of ASCI,in particular the usefulness,dosage,and potential risks of methylprednisolone(MP). Although the results of American National Acute Spinal Cord Injury Study 2 and 3 trials led to the wide adoption of a high-dose MP regimen for ASCI patients,the reliabilities of their study methods and data were still questionable. Based on the currently available literature,we conclude that high-dose MP is no longer a recommended therapy for ASCI;however,due to the lack of effective treatment,it remains a useful option for this condition.


Assuntos
Metilprednisolona/uso terapêutico , Fármacos Neuroprotetores/uso terapêutico , Traumatismos da Medula Espinal/tratamento farmacológico , Ensaios Clínicos como Assunto , Humanos , Resultado do Tratamento
10.
Zhonghua Yu Fang Yi Xue Za Zhi ; 46(6): 556-60, 2012 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-22943906

RESUMO

OBJECTIVE: To assess the immunotoxicologic effects of genetically modified drought resistant wheat T349 with GmDREB1 gene. METHODS: A total of 250 female BALB/c mice (6-8 week-old, weight 18-22 g) were divided into five large groups (50 mice for each large group) by body weight randomly. In each large group, the mice were divided into five groups (10 mice for each group) by body weight randomly, which were set as negative control group, common wheat group, parental wheat group, genetically modified wheat group and cyclophosphamide positive control group, respectively. Mice in negative control and positive control group were fed with feedstuff AIN-93G, mice in common wheat group, non-genetically modified parental wheat group and genetically modified wheat group were fed with feedstuffs added corresponding wheat (proportion up to 76%) for 30 days, then body weight, organ coefficient of spleen and thymus, peripheral blood lymphocytes phenotyping, serum cytokine, serum immunoglobulin, antibody plaque-forming cell (PFC), serum 50% hemolytic value (HC50), mitogen-induced splenocyte proliferation, delayed-type hypersensitivity (DTH) reaction and phagocytic activities of phagocytes were detected respectively. RESULTS: After 30 days raise, among negative control group, common wheat group, non-genetically modified parental wheat group, genetically modified wheat group and cyclophosphamide positive control group, mice body weight were (21.0±0.3), (20.4±0.7), (21.1±1.0), (21.1±1.0), (19.4±1.0) g, respectively (F=7.47, P<0.01); organ coefficient of spleen were (0.407±0.047)%, (0.390±0.028)%, (0.402±0.042)%, (0.421±0.041)%, (0.304±0.048)%, respectively (F=12.41, P<0.01); organ coefficient of thymus were (0.234±0.032)%, (0.246±0.028)%, (0.249±0.040)%, (0.234±0.034)%, (0.185±0.039)%, respectively (F=5.58, P<0.01); the percentage of T cell in peripheral blood were (70.43±4.44)%, (68.33±5.37)%, (73.04±2.68)%, (74.42±2.86)%, (90.42±1.66)%, respectively (F=57.51, P<0.01); the percentage of B cell were (13.89±3.19)%, (15.34±4.84)%, (13.06±4.22)%, (12.93±2.36)%, (3.01±0.96)%, respectively (F=12.79, P<0.01); the percentage of Th cell were (55.87±3.80)%, (55.24±4.60)%, (57.92±3.70)%, (59.57±2.54)%, (77.37±2.31)%, respectively (F=68.58, P<0.01);the Th/Ts ratio were 4.16±0.29, 4.73±0.96, 4.19±0.78, 4.52±0.40, 6.34±0.73, respectively (F=17.57, P<0.01);the serum IgG were (1046.38±210.67), (1065.49±297.22), (1517.73±299.52), (1576.67±241.92), (1155.88±167.05) µg/ml, respectively (F=10.53, P<0.01); the serum IgM were (333.83±18.97), (327.73±27.72), (367.47±27.18), (363.42±46.14), (278.71±24.42) µg/ml, respectively (F=12.11, P<0.01); the serum IgA were (51.69±10.10), (42.40 ± 8.35), (32.11±4.22), (37.12±4.90), (41.45±8.89) µg/ml, respectively (F=8.25, P<0.01); the PFC were (29.2±14.6), (28.0±20.0), (34.8±30.9), (33.2±25.1), (4.8±5.3) per 10(6) splenocyte, respectively (F=3.33, P<0.05); the HC50 were 82.3±6.5, 79.7±4.6, 75.8±4.1, 74.9±3.6, 70.8±2.1, respectively (F=9.99, P<0.01);the LPS-induced splenocyte proliferation were 0.21±0.10, 0.21±0.14, 0.26±0.12, 0.25±0.14, 0.07±0.06, respectively (F=4.18, P<0.05). CONCLUSION: The genetically modified drought-resistant wheat T349 was substantially equivalent to parental wheat in the effects on immune organs and immunologic functions of mice, and it didn't show immunotoxicity.


Assuntos
Secas , Plantas Geneticamente Modificadas/toxicidade , Triticum/genética , Triticum/toxicidade , Animais , Testes Imunológicos de Citotoxicidade , Citotoxicidade Imunológica , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Plantas Geneticamente Modificadas/imunologia , Triticum/imunologia
11.
Zhonghua Wai Ke Za Zhi ; 49(8): 707-11, 2011 Aug 01.
Artigo em Chinês | MEDLINE | ID: mdl-22168934

RESUMO

OBJECTIVES: To summarize the experiences in clinical application of neuronavigation in transsphenoidal microsurgery of specific pituitary adenomas, and to discuss its indications. METHODS: From January 2006 to December 2010, 138 cases of transsphenoidal microsurgery for specific pituitary adenomas under neuronavigation were reviewed. The indications for neuronavigation in transsphenoidal microsurgery includes: recurrent or regrowth of residual pituitary adenomas after former transsphenoidal surgery in 36 cases, invasive pituitary adenomas in 45 cases, extremely laterally or deeply situated microadenomas in 45 cases, poor pneumatization of the sphenoid in 4 cases, skull base anomalies due to osteodysplasia fibrosa in 3 cases, narrow space between bilateral internal carotid arteries in 4 cases, distortion of nasal septum in 1 case. RESULTS: In the recurrence group, 12 were totally removed, 9 subtotally removed; postoperative complications included hematoma within the tumor cavity in 2 cases, cerebrospinal fluid (CSF) leakage in 4 cases among which 3 developed intracranial infection and 2 communicating hydrocephalus, oculomotor paralysis in 1 case and hypopituitarism in 3 cases; 9 were cured and 8 remission. In the invasive group, 5 were totally removed, 27 subtotally removed; postoperative complications included hematoma within the tumor cavity in 1 case, CSF leakage and intracranial infection in 1 case; 2 were cured and 22 remission. None of the 30 invasive hormone-secreting adenomas were cured or remission. The 45 cases of hormone-secreting microadenomas were all totally removed, among which 38 were cured. Among the poor sphenoid pneumatization group, total and subtotal tumor removal were achieved in 2 cases respectively with only one cured. In the skull base anomaly group, 2 were totally removed and 1 subtotally removed, with only one cured. For the cases with narrow space between bilateral internal carotid arteries and distortion of nasal septum, all were totally removed and cured. CONCLUSIONS: Transsphenoidal microsurgery under neuronavigation can be applied for pituitary adenomas in above specific indications. It is an accurate, safe and effective approach for specific pituitary adenomas, which can not only expand the indication of transsphenoidal microsurgery for pituitary adenomas, but also reduce the harmful exposure of X-rays for the operating staff.


Assuntos
Adenoma/cirurgia , Neuronavegação , Neoplasias Hipofisárias/cirurgia , Adolescente , Adulto , Idoso , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Seio Esfenoidal/cirurgia , Adulto Jovem
12.
Zhonghua Wai Ke Za Zhi ; 49(6): 546-50, 2011 Jun 01.
Artigo em Chinês | MEDLINE | ID: mdl-21914308

RESUMO

OBJECTIVE: To study the clinical characteristics, diagnosis and surgical effects of thyroid-stimulating hormone pituitary adenomas (TSH-omas). METHODS: The clinical data of 19 patients (14 female and 5 male) with TSH-omas were analyzed retrospectively in this study from January 2001 to December 2008. The patients ranged from 20 to 70 years old (average 40.5 years old) and had disease histories from 1 to 228 months (average 55 months). Among these patients, 15 of them complained of thyrotoxicosis symptoms, while the other 4 patients' symptoms were associated with headache and/or visual disturbance caused by the tumor mass effect. Initially, 12 of the 15 patients with thyrotoxicosis symptoms were misdiagnosed with Grave's disease. As a result 2 of them received (131) Iodine, and one received subtotal thyroidectomy. All of these patients underwent transsphenoidal microsurgery. RESULTS: Average follow-up period was 3.6 years (6 months-7 years). Pathological analysis of the surgical specimen showed pituitary adenoma in all patients, immunohistochemistry were positive for TSH in 17 cases, negative for TSH in 2, positive for growth hormone in 2, positive for prolactin in 1, and positive for adrenocorticotrophic hormone in 1. Postoperative MRI revealed that the tumors in 15 patients were removed totally, though 4 patients still had residual tumors. The thyroid hormone level tests suggested that 13 patients could be considered normal 3 months after their tumors were removed, though 2 of patients with normal postoperative MRI and thyroid hormones showed increased levels of TSH. For these 2 patients, tumors did not recur and their thyroid hormone levels returned to normal after pituitary radiotherapy. The cure rate was 11/19 after surgery and 13/19 after surgery plus pituitary radiotherapy. CONCLUSIONS: The screening test for hyperthyroidism patients with high TSH levels is a key point to improve the accuracy rate in early diagnoses of TSH-omas. The transsphenoidal microsurgery is first choice to treat TSH-omas, while pituitary radiotherapy and somatostatin analogs are beneficially adjunctive therapies.


Assuntos
Hipertireoidismo/metabolismo , Neoplasias Hipofisárias/diagnóstico , Neoplasias Hipofisárias/cirurgia , Tireotropina/metabolismo , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Hipofisárias/metabolismo , Estudos Retrospectivos , Adulto Jovem
13.
Bioorg Med Chem ; 19(13): 4043-50, 2011 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-21664827

RESUMO

Ursolic acid (UA) as the leader compound was designed to prepare a series of derivatives (three novel compounds UA-1a, UA-1b and UA-2) by modification at the C3 and C28 positions. Their chemical structures were confirmed by IR, (1)H NMR and MS. The cytotoxic activity of the derivatives was evaluated against HepG2, BGC-823 and HT-29 by the MTT assay. The novel derivative UA-1a, [3ß-acetoxy-urs-12-en-28-oyl]-1-monoglyceride showed significant anti-growth ability against the assayed cancer cell lines, particularly against BGC-823, while low cytotoxicity to human normal gastric cell line GES-1. Further investigation revealed that UA-1a could induce apoptotic events of the treated BGC-823 cells, such as comet-like DNA bend, sub-G0/G1 phase accumulation and phosphatidylserine externalization. The activity of Caspase-3 was found to be up-regulated, while the expression of Bcl-2 and Survivin were down-regulated in UA-1a treated cells. UA-1a might trigger the death of BGC-823 cells by inducing apoptosis via the mitochondria pathway. UA-1a exerted stronger ability than Taxol to retard tumor growth in nude mice without leaving apparent toxicity to the hosts. The experimental data suggested that UA-1a would have a therapeutic potential in the treatment of gastric cancer.


Assuntos
Antineoplásicos/síntese química , Monoglicerídeos/síntese química , Neoplasias Gástricas/tratamento farmacológico , Triterpenos/síntese química , Antineoplásicos/uso terapêutico , Antineoplásicos/toxicidade , Caspase 3/metabolismo , Linhagem Celular Tumoral , Humanos , Proteínas Inibidoras de Apoptose/metabolismo , Monoglicerídeos/uso terapêutico , Monoglicerídeos/toxicidade , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Neoplasias Gástricas/metabolismo , Survivina , Triterpenos/uso terapêutico , Triterpenos/toxicidade
14.
Zhonghua Yi Xue Za Zhi ; 91(41): 2920-2, 2011 Nov 08.
Artigo em Chinês | MEDLINE | ID: mdl-22333614

RESUMO

OBJECTIVE: To explore the clinical efficacy of microvascular decompression plus intraoperative monitoring of abnormal muscle response in the treatment of hemifacial spasm. METHODS: Between 2009 and 2010, a total of 47 patients underwent microvascular decompression for hemifacial spasm. There were 15 males and 32 females with an age range 23 - 70 years old. During operations, intermittent electrical pulses were applied to stimulate the zygomatic branch of facial nerve at the spasm side. And evoked potentials were monitored in orbicularis oris. All patients were followed up for 5 - 22 months. RESULTS: The abnormal muscle responses were recorded pre-operatively in all 47 patients at the spasm side. In 42 patients, the abnormal muscle responses disappeared at the different stages of operations (4 while opening dura, 9 while dissecting arachnoid membrane and 29 while separating responsible vessels). All 42 patients were cured during the follow-up period. In the remaining 5 patients, the abnormal muscle response were still recorded even at the end of operations. Two of 5 patients were free from spasm during the follow-up period while the symptoms of other 3 patients became obviously relieved. CONCLUSION: The combined approaches of microvascular decompression and intraoperative monitoring of abnormal muscle response may assist the identification of responsible vessels and improve the outcomes of hemifacial spasm.


Assuntos
Espasmo Hemifacial/cirurgia , Cirurgia de Descompressão Microvascular , Monitorização Intraoperatória , Adulto , Idoso , Potenciais Evocados , Músculos Faciais/cirurgia , Feminino , Seguimentos , Espasmo Hemifacial/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem
15.
Hum Gene Ther ; 22(2): 207-15, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21128742

RESUMO

Our objective was to achieve the enhanced delivery of vascular endothelial growth factor (VEGF) to ischemically disordered brain through transferrin-coupled liposomes (Tf-PLs) via intravenous administration, and to observe the effect of Tf-VEGF-PLs on ischemic brain neuroprotection and angiogenesis. Cerebral VEGF overexpression was achieved with Tf-PLs by intravenous injection 48 hr after an acute stroke. ß-Galactosidase expression was monitored; saline was injected as a control. The success of postischemic gene transduction was confirmed by ß-galactosidase staining and by increased VEGF mRNA and protein in ischemic brain. Vascular density, neurological recovery, and ischemic area calculation were performed to evaluate the effect of Tf-VEGF-PLs. The positive expression of ß-galactosidase indirectly indicated that VEGF was successfully delivered into brain by Tf-VEGF-PLs. VEGF mRNA in the Tf-VEGF-PL group 24 hr after injection was significantly higher than in the control group (p < 0.05). Western blot analysis showed that postischemic Tf-VEGF-PLs resulted in increased VEGF protein levels compared with VEGF-PLs and saline-administered rats (p < 0.05) 48 hr after administration. At 21 days after drug injection, we observed a significant decrease in infarct volume and better neurological function in the Tf-VEGF-PL-treated group, compared with the VEGF-PL group. FITC-dextran marking showed increased vascular density in the penumbra of Tf-VEGF-PL-treated hemispheres (245,873.9, number of microvessels per field) compared with that in VEGF-PL-treated hemispheres (139,801.3) or saline-treated hemispheres (102,175.5) (p < 0.05). The remainder of the cerebral blood flow after ischemia in the Tf-VEGF-PL group was significantly more than in the control groups (0.35 vs. 0.29, 0.21; p < 0.05). We conclude that the VEGF gene can be delivered noninvasively into the brain by Tf-VEGF-PLs. Postischemic treatment with Tf-VEGF-PLs effectively promoted neuroprotection and vascular regeneration in the chronic stage of cerebral infarction.


Assuntos
Isquemia Encefálica/terapia , Encéfalo/irrigação sanguínea , Acidente Vascular Cerebral/patologia , Fator A de Crescimento do Endotélio Vascular/genética , Animais , Isquemia Encefálica/patologia , Dextranos/análise , Modelos Animais de Doenças , Fluoresceína-5-Isotiocianato/análogos & derivados , Fluoresceína-5-Isotiocianato/análise , Terapia Genética , Injeções Intravenosas , Lipossomos , Masculino , Fármacos Neuroprotetores/farmacologia , Ratos , Ratos Sprague-Dawley , Transferrina/metabolismo , beta-Galactosidase/metabolismo
16.
Zhonghua Wai Ke Za Zhi ; 48(19): 1451-3, 2010 Oct 01.
Artigo em Chinês | MEDLINE | ID: mdl-21176650

RESUMO

OBJECTIVE: To explore and evaluate the methodology of neuro-endoscope assisted atlanto occipital decompression in Chiari type I malformation with syringomyelia. METHODS: Between January 2007 to January 2008, 8 patients underwent neuro-endoscope assisted atlanto occipital decompression, including 2 male patients and 6 female patients (aged 13 to 52 years). During the operations, the surgical fields were lightened by the illuminator of endoscope. All the manipulations were done outside the sheath of neuroendoscope. The decompression bone window was about 2.0 cm × 2.0 cm. After the atlanto occipital fascia was cleared thoroughly, dura were opened in 6 cases and intact in 2 cases. RESULTS: There were no complications observed in this study. Seven patients were determined as excellent in recovery according to the Tator criteria because of apparent improvements in superficial sensation. Five of the seven patients had improvements in muscle strength. One patient was assessed as good because of stable symptom without deterioration. CONCLUSION: Neuro-endoscope assisted atlanto occipital decompression is a potential technique worthy of employing in the mini-invasive neurosurgical technology.


Assuntos
Malformação de Arnold-Chiari/cirurgia , Descompressão Cirúrgica/métodos , Siringomielia/cirurgia , Adolescente , Adulto , Malformação de Arnold-Chiari/complicações , Endoscopia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Siringomielia/complicações , Resultado do Tratamento , Adulto Jovem
17.
Chin Med J (Engl) ; 123(14): 1878-83, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20819571

RESUMO

BACKGROUND: In order to make posterior fossa decompression for the management of Chiari I malformation simple and less invasive while using direct visualization, a novel solely endoscopic procedure has been employed for the decompression of Chiari malformation type I. The objective of this study was to present neural endoscopic posterior fossa decompression and atlas laminectomy for Chiari type I patients. METHODS: Twenty-one patients with Chiari type I underwent neural endoscopic posterior fossa decompression and atlas laminectomy. We described the procedure for neural endoscopic posterior fossa decompression and atlas laminectomy. All patients in this series demonstrated cerebellar tonsil herniation below the foramen magnum in addition to syringomyelia. All patients in the reviewed study underwent preoperative MRI as well as 3-month postoperative MRI. Additional follow-up MRI varied but was usually repeated 12 months to 18 months after surgery. Postoperative MRI studies were retrospectively reviewed and compared with preoperative studies. RESULTS: All patients showed clinical improvements, and none had any complications. Patients with syringomyelia had symptoms entirely disappear. Eleven patients (52.4%) experienced radiographic improvement in syringomyelia (decreased size or resolution) during the follow-up period. Nine patients (42.8%) demonstrated decreased syrinx size and four (19%) demonstrated resolved syrinx. Of the 15 patients with symptomatic syringomyelia, 11 (73.3%) experienced symptomatic improvement. The median time to symptom improvement was four months after surgery. Post surgical MRI examinations indicated complete and sufficient decompression of foramen magnum region. CONCLUSIONS: Endoscope atlanto-occipital decompression surgery is an innovative, safe and effective surgical procedure. It has similar results compared to traditional surgery, however with the added advantages of being minimal invasive, having fewer complications, decreased influence on stability of occipital bony structure, and a faster recovery as well as reduced hospital stay and expenses.


Assuntos
Malformação de Arnold-Chiari/cirurgia , Endoscopia/métodos , Siringomielia/cirurgia , Adolescente , Criança , Descompressão Cirúrgica/métodos , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Estudos Retrospectivos
18.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 32(3): 332-5, 2010 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-20602890

RESUMO

OBJECTIVE: To summarize the diagnosis and treatment of pulmonary thromboembolism (PTE) in post-operative neurosurgical patients. METHODS: We retrospectively analyzed the clinical data of 7 patients who experienced pulmonary thromboembolism after neurosurgical operations in our department from October 2009 to March 2010. RESULTS: Of these 7 patients, 6 were confirmed with computed tomographic pulmonary angiography (CTPA) and 1 was diagnosed according to the clinical manifestations and other diagnostic examinations. All the patients were treated initially with low-dose heparin or low-molecular-weight heparin and then with warfarin. Two patients were implanted with permanent inferior vena cava filters before anticoagulation. One received anticoagulant therapy and died of respiratory failure due to pulmonary embolism on the fourth post-operative day. Six patients were discharged after significant improvement. CONCLUSIONS: Many risk factors may cause PTE peri-operatively. Post-operative CTPA may be indicated. Anticoagulation and other management strategies may be applied to improve the outcome.


Assuntos
Complicações Pós-Operatórias , Embolia Pulmonar/diagnóstico , Embolia Pulmonar/terapia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/terapia , Embolia Pulmonar/etiologia , Estudos Retrospectivos
19.
J Neurosurg ; 112(1): 108-17, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19408986

RESUMO

OBJECT: The standard transsphenoidal approach has been successfully used to resect most pituitary adenomas. However, as a result of the limited exposure provided by this procedure, complete surgical removal of pituitary adenomas with parasellar or retrosellar extension remains problematic. By additional bone removal of the cranial base, the extended transsphenoidal approach provides better exposure to the parasellar and clival region compared with the standard approach. The authors describe their surgical experience with the extended transsphenoidal approach to remove pituitary adenomas invading the anterior cranial base, cavernous sinus (CS), and clivus. METHODS: Retrospective analysis was performed in 126 patients with pituitary adenomas that were surgically treated via the extended transsphenoidal approach between September 1999 and March 2008. There were 55 male and 71 female patients with a mean age of 43.4 years (range 12-75 years). There were 82 cases of macroadenoma and 44 cases of giant adenoma. RESULTS: Gross-total resection was achieved in 78 patients (61.9%), subtotal resection in 43 (34.1%), and partial resection in 5 (4%). Postoperative complications included transient cerebrospinal rhinorrhea (7 cases), incomplete cranial nerve palsy (5), panhypopituitarism (5), internal carotid artery injury (2), monocular blindness (2), permanent diabetes insipidus (1), and perforation of the nasal septum (2). No intraoperative or postoperative death was observed. CONCLUSIONS: The extended transsphenoidal approach provides excellent exposure to pituitary adenomas invading the anterior cranial base, CS, and clivus. This approach enhances the degree of tumor resection and keeps postoperative complications relatively low. However, radical resection of tumors that are firm, highly invasive to the CS, or invading multidirectionally remains a big challenge. This procedure not only allows better visualization of the tumor and the neurovascular structures but also provides significant working space under the microscope, which facilitates intraoperative manipulation. Preoperative imaging studies and new techniques such as the neuronavigation system and the endoscope improve the efficacy and safety of tumor resection.


Assuntos
Adenoma/cirurgia , Procedimentos Neurocirúrgicos/métodos , Neoplasias Hipofisárias/cirurgia , Neoplasias da Base do Crânio/cirurgia , Osso Esfenoide/cirurgia , Adenoma/patologia , Adolescente , Adulto , Idoso , Seio Cavernoso/patologia , Seio Cavernoso/cirurgia , Criança , Fossa Craniana Posterior/patologia , Fossa Craniana Posterior/cirurgia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos/efeitos adversos , Neoplasias Hipofisárias/patologia , Estudos Retrospectivos , Base do Crânio/patologia , Base do Crânio/cirurgia , Neoplasias da Base do Crânio/patologia , Osso Esfenoide/patologia , Resultado do Tratamento , Adulto Jovem
20.
Chin Med J (Engl) ; 122(17): 2022-6, 2009 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-19781389

RESUMO

BACKGROUND: Cholecystokinin (CCK) is one of the richest neuropeptides in the mammalian brain, which is mainly distributed in the cerebral cortex, hippocampus, thalamus and caudate-putamen. CCK is implicated in a variety of behavioral functions such as food intake, learning, memory, anxiety, pain and neuroprotection. The current research results for CCK are obtained mainly through injection of CCK peptide into the body. The key issues of whether CCK can regulate diet by a central pathway and whether there are long-term regulation effects on diet are still unresolved. In this study, the effects of CCK on food intake in transgenic mice were investigated. METHODS: Transgenic mice were created by microinjection of the PDGF-CCK construct into male pronucleus of the zygotes. The genomic phonetype of transgenic mice were identified by PCR. The expression of PDGF-CCK was analyzed by Western blotting. Body weight, plasma glucose, cholesterol and triglycerides were assayed and analyzed. RESULTS: Two PDGF-CCK transgenic independent lines were established and exhibited a high-levels brain-specific transgene expression compared with that of nontransgenic littermate controls. The food intake of male CCK transgenic mice was decreased by 5% - 10% with the same levels of water consumed compared with wild type mice. The food intake in female mice was not obviously changed. In the transgenic mice the bodyweight was lower and plasma glucose was higher compared with the nontransgenic littermate controls. CONCLUSIONS: The high expression of the CCK gene in the brain can decrease body weight and increase plasma glucose. The differences in food intake between the males and females require further study.


Assuntos
Colecistocinina/genética , Ingestão de Alimentos/genética , Camundongos Transgênicos , Animais , Glicemia/genética , Glicemia/fisiologia , Western Blotting , Peso Corporal/genética , Peso Corporal/fisiologia , Encéfalo/metabolismo , Colecistocinina/metabolismo , Colesterol/sangue , Feminino , Lipase/sangue , Masculino , Camundongos , Camundongos Endogâmicos C57BL
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