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1.
Lupus ; 29(2): 191-198, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31959041

RESUMO

OBJECTIVE: This study aimed to investigate how septicaemia, non-septicaemia infection and the disease itself are associated with disease activity and mortality in inpatients with systemic lupus erythematosus (SLE) in Taiwan. METHODS: We retrospectively reviewed 1115 patients and enrolled 427 with SLE admitted for lupus flare-ups and co-morbidities. Disease activity and infection type/site were recorded and categorized according to the causes of admission and mortality into three categories, of which two were specified as follows: (a) septicaemia admissions, non-septicaemia admissions; and (b) septicaemia mortality, non-septicaemia infection mortality and non-infection mortality. The relationships between lupus flare-ups and mortality in different groups were analysed using an unpaired t-test, Mann-Whitney U-test and logistic regression. RESULTS: Septicaemia was the major cause of mortality in SLE inpatients. There were 98 (22.95%) mortality patients among all 427 SLE patients. The septicaemia admissions had higher disease activity (SLE Disease Activity Index 2000 = 13.00 ± 7.98) than the non-septicaemia admissions (9.77 ± 5.72; p < 0.01). The mean current SLEDAI score of the septicaemia mortality group (14.91 ± 8.01) was higher than that of the non-septicaemia infection mortality group (10.05 ± 5.75; p = 0.02), in spite of the similar mean earlier SLEDAI score. The risk of mortality in the septicaemia mortality group due to previous septicaemia admissions was 13.2 times (odds ratio) higher than in the non-septicaemia infection mortality group and 15.6 times higher than in the non-infection mortality group. CONCLUSION: Septicaemia relates to increased lupus disease activity and is associated with a greater risk of mortality in the SLE patients than other causes of admission. Fewer previous septicaemia admissions decrease the risk of septicaemia mortality.


Assuntos
Hospitalização/estatística & dados numéricos , Lúpus Eritematoso Sistêmico/mortalidade , Sepse/mortalidade , Índice de Gravidade de Doença , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Comorbidade , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Taiwan/epidemiologia , Adulto Jovem
2.
Oncogene ; 36(34): 4929-4942, 2017 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-28436951

RESUMO

Hypoxia plays a critical role during the evolution of malignant cells and tumour microenvironment (TME).Tumour-derived exosomes contain informative microRNAs involved in the interaction of cancer and stromal cells, thus contributing to tissue remodelling of tumour microenvironment. This study aims to clarify how hypoxia affects tumour angiogenesis through exosomes shed from lung cancer cells. Lung cancer cells produce more exosomes under hypoxic conditions than do parental cells under normoxic conditions. miR-23a was significantly upregulated in exosomes from lung cancer under hypoxic conditions. Exosomal miR-23a directly suppressed its target prolyl hydroxylase 1 and 2 (PHD1 and 2), leading to the accumulation of hypoxia-inducible factor-1 α (HIF-1 α) in endothelial cells. Consequently, hypoxic lung cancer cells enhanced angiogenesis by exosomes derived from hypoxic cancer under both normoxic and hypoxic conditions. In addition, exosomal miR-23a also inhibits tight junction protein ZO-1, thereby increasing vascular permeability and cancer transendothelial migration. Inhibition of miR-23a by inhibitor administration decreased angiogenesis and tumour growth in a mouse model. Furthermore, elevated levels of circulating miR-23a are found in the sera of lung cancer patients, and miR-23a levels are positively correlated with proangiogenic activities. Taken together, our study reveals the clinical relevance and prognostic value of cancer-derived exosomal miR-23a under hypoxic conditions, and investigates a unique intercellular communication, mediated by cancer-derived exosomes, which modulates tumour vasculature.


Assuntos
Permeabilidade Capilar/fisiologia , Exossomos/metabolismo , Neoplasias Pulmonares/metabolismo , MicroRNAs/metabolismo , Neovascularização Patológica/metabolismo , Prolil Hidroxilases/metabolismo , Proteína da Zônula de Oclusão-1/metabolismo , Animais , Hipóxia Celular/fisiologia , Linhagem Celular , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Células Endoteliais da Veia Umbilical Humana , Humanos , Hipóxia/metabolismo , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteínas de Junções Íntimas/metabolismo
3.
Mater Sci Eng C Mater Biol Appl ; 75: 1-6, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-28415381

RESUMO

Safety and reliability are crucial issues for medical instruments and implants. In the past few decays, bulk metallic glasses (BMGs) have drawn attentions due to their superior mechanical properties, good corrosion resistance, antibacterial and good biocompatibility. However, most Zr-based and Ti-based BMGs contain Ni as an important element which is prone to human allergy problem. In this study, the Ni-free Ti-based and Zr-based BMGs, Ti40Zr10Cu36Pd14, and Zr48Cu36Al8Ag8, were selected for systematical evaluation of their biocompatibility. Several biocompatibility tests, co-cultural with L929 murine fibroblast cell line, were carried out on these two BMGs, as well as the comparison samples of Ti6Al4V and pure Cu. The results in terms of cellular adhesion, cytotoxicity, and metallic ion release affection reveal that the Ti40Zr10Cu36Pd14 BMG and Ti6Al4V exhibit the optimum biocompatibility; cells still being attached on the petri dish with good adhesion and exhibiting the spindle shape after direct contact test. Furthermore, the Ti40Zr10Cu36Pd14 BMG showed very low Cu ion release level, in agreement with the MTT results. Based on the current findings, it is believed that Ni-free Ti-based BMG can act as an ideal candidate for medical implant.


Assuntos
Fibroblastos/metabolismo , Vidro/química , Teste de Materiais , Titânio/química , Zircônio/química , Animais , Adesão Celular , Linhagem Celular , Fibroblastos/citologia , Camundongos , Níquel
4.
Osteoarthritis Cartilage ; 24(1): 129-33, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26241778

RESUMO

OBJECTIVE: Although anterior cruciate ligament (ACL) injury is a well-recognized risk factor for developing knee post-traumatic osteoarthritis (PTOA), the process in the patellofemoral (PF) joint after ACL injury is still under-researched. Our aim was to investigate the perfusion changes in PF subchondral bone marrow in the rat ACL transection (ACLX) model of PTOA using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). DESIGN: Eighteen male Sprague Dawley rats were randomly separated into three groups (n = 6 each group): a normal control group and groups receiving ACLX and sham-surgery, respectively, in the right knee. Perfusion parameters in the patellar and femoral subchondral bone marrows of all rats were measured on DCE-MRI at 0, 4, 8, and 16 weeks after respective treatment. After the last MRI at week 16, the rats were sacrificed and their right knees were harvested for histologic examination. In addition, to observe the long-term histologic change in PF joints, 9 additional rats (n = 3 in each group) were included and sacrificed at week 32 for histologic examination. RESULTS: In the ACLX group vs the sham and control groups, the perfusion parameters were significantly changed in both patellar and femoral subchondral bone marrows at week 16. Histologic examination revealed cartilage defects in ACLX rats at 32 weeks after surgery. CONCLUSIONS: These data point to a possible functional relationship between subchondral bone marrow perfusion abnormalities and cartilage breakdown in PTOA. Moreover, the perfusion parameters derived from DCE-MRI can potentially serve as biomarkers of early OA.


Assuntos
Lesões do Ligamento Cruzado Anterior , Medula Óssea/irrigação sanguínea , Fêmur/irrigação sanguínea , Osteoartrite do Joelho/fisiopatologia , Patela/irrigação sanguínea , Animais , Meios de Contraste , Traumatismos do Joelho/complicações , Imageamento por Ressonância Magnética , Masculino , Osteoartrite do Joelho/etiologia , Ratos , Ratos Sprague-Dawley
5.
Neuroradiol J ; 25(6): 649-56, 2012 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-24029176

RESUMO

Magnetic resonance susceptibility-weighted imaging (SWI), a novel 3D gradient echo MRI sequence exploiting phase and magnitude data for post-processing, is able to detect blood, iron, calcification and deoxygenated hemoglobin content for brain. SWI has been widely used to evaluate cerebral vascular disorders, trauma, multiple sclerosis, and tumors. We have also used SWI to evaluate acute stroke patients to identify thrombosis and possible penumbra. The acquisition was too long for examining acute stroke patients due to motion from agitation and mental changes. We have altered the parameters of phase resolution, voxel size, matrix size and partial Fourier to shorten the acquisition time to improve the diagnostic quality of SWI for acute stroke patients. The result was to reduce the acquisition time from 3:46 min to 2:14 min thereby providing a helpful tool in screening stroke patients.

6.
Acta Neurol Scand ; 123(3): 187-92, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20569227

RESUMO

OBJECTIVE: Percutaneous carotid angioplasty and stenting (CAS) has been used to improve cerebral circulation and autoregulation. However, whether CAS ameliorates the autonomic regulatory dynamics remains unclear. This prospective study examines the neurocardiovascular dynamics following carotid stenting. METHODS: Thirty minutes electrocardiograms were recorded at three different time points (pre-operative, 1-h post-operative, 1-day post-operative) on twelve male patients (mean age 70.8 ± 9.6 years) receiving unilateral primary CAS. The HR data were analyzed by the conventional heart rate variability (HRV) and the multiscale entropy (MSE) methods; the former associates with autonomic activities and the latter quantifies the regulatory complexity of heart beat intervals. Loss of complexity at multiple scales has been associated with decoupled regulatory network in vivo. RESULTS: Conventional HRV indices showed no difference after CAS. Complexity indices increased significantly on scales 2-8 at 1-h and on scales 2-3 1-day post-treatment. The lower scale MSE (1-5) correlated with the frequency components of conventional HRV indices. The increased complexity could imply a restoration of the neurocardiovascular dynamics on the path to a healthier state. CONCLUSIONS: Primary CAS can induce a recovery in the neurocardiovascular regulatory dynamics in patients with high-grade carotid stenosis.


Assuntos
Estenose das Carótidas/fisiopatologia , Estenose das Carótidas/terapia , Stents , Doença Aguda , Idoso , Idoso de 80 Anos ou mais , Angioplastia/métodos , Estenose das Carótidas/diagnóstico , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Exame Neurológico/métodos , Projetos Piloto , Estudos Prospectivos , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/fisiopatologia , Acidente Vascular Cerebral/terapia
7.
Osteoarthritis Cartilage ; 18(1): 54-60, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19761884

RESUMO

OBJECTIVE: The purpose of this study was to investigate whether the effect of treatment with hyaluronic acid (HA) on cartilage in osteoarthritis (OA) can be determined by measuring the magnetic resonance (MR) T2 value of cartilage in an anterior cruciate ligament transection (ACLX) animal model. METHOD: Eighteen male Sprague Dawley rats were separated randomly into three groups (n=6 for each group). Group 1 was given ACLX and intra-articular (IA) normal saline (NS) injection (ACLX+NS), group 2 was given ACLX and IA HA injection (ACLX+HA), and group 3 was the sham control. The ACLX+NS and ACLX+HA groups received ACLX on the right knee at 8 weeks of age and were then treated with IA NS or HA injection once a week, respectively, for 4 weeks starting at 13 weeks of age. In the sham-control group, the right knee joint was opened surgically but ACLX was not performed at 8 weeks of age. MR T2 measurements were obtained on all rats at 8, 12, and 21 weeks of age, and histological Mankin scoring was performed at 21 weeks of age. RESULTS: Five weeks after the 4-week treatment, the MR T2 value of the ACLX right knee cartilage was significantly lower in ACLX+HA (29.58+/-1.12ms) than in ACLX+NS (32.04+/-1.39ms) (P<0.05). Five weeks after the 4-week treatment, the Mankin score of the ACLX right knee was significantly lower in ACLX+HA (3.3+/-0.81) than in ACLX+NS (7.3+/-1.03) (P<0.001). The T2 value was significantly and positively correlated with the Mankin score in the ACLX+NS (rho=0.77, P<0.05) and ACLX+HA (rho=0.69, P<0.05) groups. CONCLUSION: This study demonstrates the feasibility of quantitative MR T2 measurement in the early assessment of HA treatment efficiency in a cartilage degeneration model.


Assuntos
Adjuvantes Imunológicos/uso terapêutico , Lesões do Ligamento Cruzado Anterior , Cartilagem Articular/patologia , Ácido Hialurônico/uso terapêutico , Osteoartrite do Joelho/tratamento farmacológico , Adjuvantes Imunológicos/administração & dosagem , Adjuvantes Imunológicos/farmacologia , Animais , Ligamento Cruzado Anterior/cirurgia , Artrite Experimental/patologia , Cartilagem Articular/efeitos dos fármacos , Modelos Animais de Doenças , Ácido Hialurônico/administração & dosagem , Ácido Hialurônico/farmacologia , Injeções Intra-Articulares , Imageamento por Ressonância Magnética/métodos , Masculino , Osteoartrite do Joelho/patologia , Ratos , Ratos Sprague-Dawley
8.
Osteoarthritis Cartilage ; 17(8): 988-94, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19332176

RESUMO

OBJECTIVE: The magnetic resonance (MR) T2 value of the cartilage, which has been shown in the articular cartilage to correlate with collagen fiber orientation and water content, may be helpful for early detection of chondropathy. However, the measurement and significance of MR T2 value for knee meniscus have not been well established. The purpose of this study was to investigate whether the MR T2 values in the diverse zones of the posterior horn of the knee meniscus differ between sexes in a young healthy population. METHOD: Twenty healthy volunteers, 10 men and 10 women (aged from 22 to 32 years), were enrolled for MR imaging of the right knee menisci. The T2 values of the posterior horns of the medial and lateral knee menisci were measured for the white zone, red/white zone, and red zone on images acquired with fat-suppressed multislice turbo spin-echo sequence at 3.0 T. RESULTS: The T2 value, with medial and lateral menisci considered together, increased significantly from the inner white zone (T2=8.02+/-0.60 ms), to the red/white zone (T2=8.78+/-0.99 ms), and to the outer red zone (T2=12.22+/-0.92 ms) of the posterior horns of the menisci (P<0.001). A generalized estimating equation method and multiple linear regression model showed that the T2 values averaged for the medial and lateral menisci together in the red and red/white zones were significantly lower in men than in women by 1.320 ms (P=0.002) and 0.865 ms (P<0.001), respectively, while the white zone showed no significant difference (P=0.694) between men (8.08+/-0.63 ms) and women (7.98+/-0.60 ms). CONCLUSION: Zonal and sex differences in the MR T2 values in the posterior horns of the knee menisci exist in the young healthy population. These differences may be associated with sex differences in the occurrence of knee osteoarthritis.


Assuntos
Cartilagem Articular/patologia , Articulação do Joelho/patologia , Osteoartrite do Joelho/patologia , Adulto , Cartilagem Articular/fisiologia , Estudos de Viabilidade , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Meniscos Tibiais/patologia , Meniscos Tibiais/fisiologia , Osteoartrite do Joelho/fisiopatologia , Valores de Referência , Fatores Sexuais , Adulto Jovem
9.
Osteoarthritis Cartilage ; 17(4): 441-7, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18990590

RESUMO

OBJECTIVE: Both animal and human studies using magnetic resonance imaging (MRI) show that cartilage degeneration increases the T2 value. However, it is unclear whether the T2 value correlates linearly with water content in cartilage with osteoarthritis. The purpose of this study was to investigate the relationship between the T2 value and water content using an animal model of cartilage injury measured at 4.7 T. DESIGN: Thirty Sprague Dawley rats were randomly separated into three groups (n=10 for each group). Group 1 rats were not operated on (control). Group 2 rats received a sham operation, and group 3 rats received an anterior cruciate ligament (ACL) transection. Six rats of each group were randomly assigned to T2 measurement and later subjected to ex vivo analysis of the relative water content of the knee cartilage. The other four rats in each group were killed, and the severity of cartilage degeneration was examined histologically. The knees of the six rats in the ACL transection group were imaged sequentially 4 and 13 weeks after ACL transection, and the relative water content was measured at 13 weeks. RESULTS: The cartilage T2 value was significantly higher 4 and 13 weeks after ACL transection in the operated knees than in the knees of the control and sham groups. The cartilage T2 value was significantly higher at 13 weeks than at 4 weeks in the operated knees. The T2 value was strongly positively correlated with the relative water content (R=0.885, P<0.0001). CONCLUSION: The trend of changes in the T2 values is consistent with an increase in the relative water content in our cartilage degeneration model. This model has potential use for the clinical evaluation of osteoarthritis.


Assuntos
Artrite Experimental/complicações , Doenças das Cartilagens/etiologia , Cartilagem Articular/patologia , Edema/etiologia , Osteoartrite/complicações , Animais , Lesões do Ligamento Cruzado Anterior , Artrite Experimental/etiologia , Água Corporal , Doenças das Cartilagens/diagnóstico , Edema/diagnóstico , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Masculino , Ratos , Ratos Sprague-Dawley
10.
Cephalalgia ; 28(10): 1017-22, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18624806

RESUMO

We established a cohort of 60 subjects with chronic daily headache (CDH) out of 1533 community-based elderly in 1993 and finished two short-term follow-ups in 1995 and 1997. All of the 26 survivors without dementia (4 M/22 F, mean age 82.7 +/- 3.4 years) finished the follow-up in 2006. The mean headache frequency was 8.4 +/- 11.8 days per month in the past year, and seven (27%) had persistent CDH. Based on the International Classification of Headache Disorders, 2nd edn, the CDH subtypes diagnoses were chronic migraine in three subjects, chronic tension-type headache in three, and one with medication-overuse headache. All these seven subjects had CDH during the 1995 and 1997 follow-ups. The diagnosis of CDH with migrainous features increased from 25 to 71% in those with CDH from 1993 to 2006. Migraine was the most common headache type in those with CDH resolution. Aggressive treatment should be applied especially for those with persistent CDH at short-term follow-ups.


Assuntos
Transtornos da Cefaleia/classificação , Transtornos da Cefaleia/epidemiologia , Afeto , Idoso , Idoso de 80 Anos ou mais , Analgésicos/uso terapêutico , Avaliação da Deficiência , Feminino , Seguimentos , Transtornos da Cefaleia/tratamento farmacológico , Transtornos da Cefaleia Secundários/tratamento farmacológico , Transtornos da Cefaleia Secundários/epidemiologia , Humanos , Masculino , Transtornos de Enxaqueca/tratamento farmacológico , Transtornos de Enxaqueca/epidemiologia , Medicamentos sem Prescrição/uso terapêutico , Prevalência , Prognóstico , Modelos de Riscos Proporcionais , Cefaleia do Tipo Tensional/tratamento farmacológico , Cefaleia do Tipo Tensional/epidemiologia
11.
Cephalalgia ; 28(6): 653-7, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18422723

RESUMO

Our previous study demonstrated that heavily T2-weighted magnetic resonance (MR) myelography could successfully detect abnormal cerebrospinal fluid (CSF) collections in patients with spontaneous intracranial hypotension (SIH); however, its ability to demonstrate ongoing CSF leakage sites is uncertain. Currently, computed tomographic (CT) myelography is still considered the study of choice for such a purpose. In this study, we compared the results of the two imaging modalities in two patients with SIH. CSF leakages, such as C1-2 extraspinal collections, CSF along nerve root sleeves, and epidural fluid collections were noted on both studies with minor discrepancies. CSF collection along nerve root sleeves demonstrated by MR myelography was the most likely ongoing leakage site in comparison with CT myelography. Targeted epidural blood patches in both patients resulted in complete headache resolution. Non-invasive, non-contrasted and time-saving MR myelography is a promising study for patients with SIH. Further large-scale validation studies are needed.


Assuntos
Hipertensão Intracraniana/diagnóstico por imagem , Hipertensão Intracraniana/patologia , Imageamento por Ressonância Magnética/métodos , Mielografia/métodos , Derrame Subdural/diagnóstico por imagem , Derrame Subdural/patologia , Tomografia Computadorizada por Raios X/métodos , Adulto , Líquido Cefalorraquidiano/citologia , Líquido Cefalorraquidiano/diagnóstico por imagem , Feminino , Humanos , Hipertensão Intracraniana/complicações , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Derrame Subdural/complicações
12.
Cephalalgia ; 27(8): 929-34, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17645756

RESUMO

We performed whole-spine heavily T2-weighted magnetic resonance (MR) myelography using a single-shot fast spin-echo pulse sequence in 17 patients (8 M/9 F) with spontaneous intracranial hypotension (SIH) to detect abnormal cerebrospinal fluid (CSF) collections. In addition, a group of age- and sex-matched controls were recruited. Follow-up MR myelography was also done at 3 weeks. MR myelography showed three kinds of abnormal CSF collections in 15 patients with SIH (88%): epidural fluid collection (n = 15, 88%), C1-2 extraspinal collections (n = 6, 35%) and CSF collections along nerve roots in the lower cervical or upper thoracic spines (n = 6, 35%). One patient (6%) showed a meningeal diverticulum. In contrast, none of the controls showed these findings. Overall, MR myelography results helped in early diagnosis of SIH in four (24%) patients whose initial brain MRIs failed to show typical SIH findings. Follow-up MR myelography results were compatible with the clinical changes with kappa statistics of 0.52 and an agreement rate of 76%. Our study showed heavily T2-weighted MR myelography provided a rapid, non-invasive and high yield method to diagnose and follow-up patients with SIH. Whether the CSF collections along the nerve roots represent the ongoing leakage sites warrants further study.


Assuntos
Hipotensão Intracraniana/diagnóstico , Imageamento por Ressonância Magnética , Mielografia , Medula Espinal/patologia , Adulto , Placa de Sangue Epidural , Encéfalo/patologia , Estudos de Casos e Controles , Feminino , Humanos , Hipotensão Intracraniana/terapia , Masculino
13.
Cephalalgia ; 27(2): 133-8, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17257233

RESUMO

The incidence and clinical relevance of subdural haematoma (SDH) in patients with spontaneous intracranial hypotension (SIH) remain undetermined. We reviewed 40 consecutive SIH patients (18 female, 22 male) in a tertiary hospital. Eight (20%) of them had SDH and nine (23%), non-haemorrhagic subdural collections. The presence of SDH was associated with higher frequencies of male gender, recurrence of severe headache and neurological deficits. Outcomes were satisfactory after supportive care or epidural blood patches except for one SDH patient, who developed transtentorial herniation resulting in Duret haemorrhage and infarctions of bilateral posterior cerebral artery territories. In conclusion, subdural fluid collections were common in patients with SIH. SDH was associated with headache worsening or neurological deficits. Patients with SDH generally recovered well; however, serious sequela might occur.


Assuntos
Encéfalo/patologia , Hematoma Subdural/epidemiologia , Hematoma Subdural/etiologia , Hipotensão Intracraniana/complicações , Adulto , Idoso , Analgésicos/uso terapêutico , Anti-Inflamatórios/uso terapêutico , Placa de Sangue Epidural , Feminino , Fludrocortisona/uso terapêutico , Hematoma Subdural/patologia , Humanos , Hipotensão Intracraniana/patologia , Hipotensão Intracraniana/terapia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores Sexuais , Teofilina/uso terapêutico , Vasodilatadores/uso terapêutico
14.
J Neurosci Res ; 63(4): 320-9, 2001 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-11170182

RESUMO

Integrins mediate cell-extracellular matrix connections and are particularly important during neuronal development. We here investigated the regulatory role of extracellular matrix (ECM) proteins on the synaptic transmission at developing motoneurons. Synaptic currents were recorded from innervated myocytes of 1-day-old Xenopus cultures by whole-cell recordings. Soluble fibronectin and laminin had no significant effect on the frequency of spontaneous synaptic currents (SSCs) by themselves and markedly increased SSC frequency in the presence of low concentration of protein kinase C (PKC) activators. Pretreatment with Gly-Arg-Gly-Asp-Ser peptide inhibited the SSC increasing action of 12-o-tetradecanoyl-phorbol-13-acetate (TPA, 0.5 microM) plus fibronectin, but not that of TPA plus laminin. Genistein but not cytochalasin D inhibited the SSC increasing action of TPA plus fibronectin or laminin. High concentration of TPA (5 microM) markedly increased the SSC frequency by itself and occluded the SSC increasing action of fibronectin. Very low concentration of TPA (0.05 microM) markedly enhanced the SSC frequency when the cells were plated onto fibronectin- or laminin-coated substratum for 1 day. The SSC frequency increased markedly right after a train stimulation, which was defined as post-train potentiation (PTrP), when the cultures were plated onto fibronectin substratum and chronically treated with brain-derived neurotrophic factor (BDNF). The PTrP phenomenon is not observed upon chronic treatment with neurotrophin-3, glial cell line-derived neurotrophic factor, or ciliary neurotrophic factor. Our results suggest that the activation of PKC and tyrosine kinase but not actin reorganization plays a role in the SSC potentiating action of fibronectin. BDNF exerts synergistic effects in increasing synaptic transmission in neurons grown on fibronectin substratum. ECMs in concert with neurotrophic factor may play a role in regulating synaptic function at developing motoneurons.


Assuntos
Acetilcolina/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Neurônios Motores/enzimologia , Fatores de Crescimento Neural , Proteína Quinase C/metabolismo , Animais , Fator Neurotrófico Derivado do Encéfalo/farmacologia , Carcinógenos/farmacologia , Células Cultivadas , Fator Neurotrófico Ciliar/farmacologia , Fibronectinas/farmacologia , Fator Neurotrófico Derivado de Linhagem de Célula Glial , Integrinas/metabolismo , Laminina/farmacologia , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/fisiologia , Neurônios Motores/citologia , Neurônios Motores/efeitos dos fármacos , Proteínas do Tecido Nervoso/farmacologia , Fármacos Neuroprotetores/farmacologia , Técnicas de Patch-Clamp , Solubilidade , Transmissão Sináptica/efeitos dos fármacos , Transmissão Sináptica/fisiologia , Acetato de Tetradecanoilforbol/farmacologia , Xenopus
15.
Am J Pediatr Hematol Oncol ; 12(4): 472-6, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2285129

RESUMO

A 10-year-old boy with Shwachman-Diamond syndrome and severe bone marrow failure was treated with high-dose cyclophosphamide, busulfan, and antithymocyte globulin followed by an infusion of human leukocyte antigen-identical, mixed lymphocyte culture (MLC) non-reactive sibling bone marrow. He developed cardiac arrhythmias and intractable hypotension and died on day 23 posttransplant. Autopsy findings were consistent with cyclophosphamide-induced pancarditis. The bone marrow showed signs of early engraftment. Allogeneic bone marrow transplantation may be a treatment alternative for Shwachman-Diamond syndrome with severe bone marrow failure. However, fatal posttransplant pancarditis due to doses of cyclophosphamide not usually associated with cardiac death may be an unanticipated problem. Further trials of bone marrow transplantation as therapy for this syndrome may be warranted, perhaps using lower doses of cyclophosphamide or substituting for it other immunosuppressive and myelosuppressive agents.


Assuntos
Doenças da Medula Óssea/terapia , Transplante de Medula Óssea , Ciclofosfamida/efeitos adversos , Insuficiência Cardíaca/induzido quimicamente , Neutropenia/terapia , Pancreatopatias/terapia , Criança , Humanos , Masculino , Neutropenia/genética , Pancreatopatias/genética , Pré-Medicação , Síndrome
16.
Br J Haematol ; 73(1): 112-20, 1989 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2803966

RESUMO

To determine whether the erythropoietin (epo) insensitivity of erythroid progenitor differentiation in congenital pure red cell aplasia or Diamond-Blackfan anaemia is intrinsic to the progenitor itself or is due to defective accessory cell function or active suppression, progenitors from normals and two patients (one steroid resistant and one spontaneously remitting), separated from all known accessory cells using sequential negative selection techniques (adherence, E-rosetting, and direct and indirect immune-panning), were studied. Initially, we evaluated three patients with DBA using unfractionated bone marrow mononuclear cells. Progenitors from two steroid non-responsive patients showed insensitivity to crude epo (c-epo) while one steroid responsive patient demonstrated normal in vitro sensitivity to c-epo. When recombinant epo (r-epo) was used in place of c-epo, the two steroid non-responders continued to demonstrate in vitro progenitor epo insensitivity. However, sensitivity of progenitors from the steroid responder, which was normal in the presence of c-epo, became abnormal when recombinant epo (r-epo) was substituted. Thus, using unfractionated bone marrow, the abnormal response to epo of progenitors from some patients with DBA appears to be obscured by stimulating factors termed erythroid burst-promoting activity (BPA) which are present in c-epo. Using fractionated highly enriched progenitors, from normals and a steroid responsive patient a final 3-10-fold enrichment of progenitors was achieved, but no such enrichment was seen when marrow from a steroid resistant patient was cultured. The epo sensitivities of normal and of patient erythroid progenitors were similar. However, at sub-optimal epo concentrations in both patients CFU-E responsiveness to crude BPA was abnormal compared to the three controls. We conclude from these studies that in DBA: (a) the failure of erythropoiesis is due to an intrinsic progenitor defect; (b) this defect involves progenitor insensitivity to factors in addition to erythropoietin: and (c) there exists a spectrum of disease reflected in the degree of the in vitro abnormality observed.


Assuntos
Anemia Aplástica/sangue , Eritropoese , Células-Tronco Hematopoéticas/fisiologia , Adolescente , Medula Óssea/patologia , Separação Celular , Células Cultivadas , Criança , Pré-Escolar , Relação Dose-Resposta a Droga , Eritropoetina/farmacologia , Humanos , Lactente , Interleucina-3/farmacologia , Proteínas Recombinantes/farmacologia
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