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81.
Recovery from paralysis in adult rats using embryonic stem cells   总被引:5,自引:0,他引:5  
OBJECTIVE: We explored the potential of embryonic stem cell-derived motor neurons to functionally replace those cells destroyed in paralyzed adult rats. METHODS: We administered a phosphodiesterase type 4 inhibitor and dibutyryl cyclic adenosine monophosphate to overcome myelin-mediated repulsion and provided glial cell-derived neurotrophic factor within the sciatic nerve to attract transplanted embryonic stem cell-derived axons toward skeletal muscle targets. RESULTS: We found that these strategies significantly increased the success of transplanted axons extending out of the spinal cord into ventral roots. Furthermore, transplant-derived axons reached muscle, formed neuromuscular junctions, were physiologically active, and mediated partial recovery from paralysis. INTERPRETATION: We conclude that restoration of functional motor units by embryonic stem cells is possible and represents a potential therapeutic strategy for patients with paralysis. To our knowledge, this is the first report of the anatomical and functional replacement of a motor neuron circuit within the adult mammalian host.  相似文献   
82.
We report a fatal case of encephalitis caused by Acanthamoeba in a 24-year-old woman from India with systemic lupus erythematosus. Diagnosis was made by identification of amebas in brain sections by immunofluorescence analysis and confirmed by demonstrating Acanthamoeba mitochondrial 16S rRNA gene DNA in brain tissue sections.  相似文献   
83.
We describe a rare case of pupillary-iris-lens membrane with goniodysgenesis, a unilateral neurocristopathy. The membrane represents ectopic iris on the lens with abnormal iris stroma and anterior chamber angle from aberrant induction, migration or regression of neural crest cells. The membrane can be progressive. Catastrophic vision loss from angle closure can occur and may be controlled with surgery. This subject needed treatment for amblyopia.  相似文献   
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Endocannabinoids block status epilepticus in cultured hippocampal neurons   总被引:3,自引:0,他引:3  
Status epilepticus is a serious neurological disorder associated with a significant morbidity and mortality. Antiepileptic drugs such as diazepam, phenobarbital and phenytoin are the mainstay of status epilepticus treatment. However, over 20% of status epilepticus cases are refractory to the initial treatment with two or more antiepileptic drugs. Endocannabinoids have been implicated as playing an important role in regulating seizure activity and seizure termination. This study evaluated the effects of the major endocannabinoids methanandamide and 2-arachidonylglycerol (2-AG) on status epilepticus in the low-Mg(2+) hippocampal neuronal culture model. Status epilepticus in this model was resistant to treatment with phenobarbital and phenytoin. Methanandamide and 2-AG inhibited status epilepticus in a dose-dependent manner with an EC(50) of 145+/-4.15 nM and 1.68+/-0.19 microM, respectively. In addition, the anti-status epilepticus effects of methanandamide and 2-AG were mediated by activation of the cannabinoid CB(1) receptor since they were blocked by the cannabinoid CB(1) receptor antagonist AM251. These results provide the first evidence that the endocannabinoids, methanandamide and 2-AG, are effective inhibitors of refractory status epilepticus in the hippocampal neuronal culture model and indicate that regulating the endocannabinoid system may provide a novel therapeutic approach for treating refractory status epilepticus.  相似文献   
86.
The aim of our study was to determine the pattern of female reproductive organ growth in Indian girls from birth to 18 years of age and to correlate the uterine length, mean ovarian volume (MOV) and Fundo Cervical Ratio (FCR) with chronological age, bone age and pubertal breast staging. A cross sectional study was performed on 218 girls from birth to 18 years of age. Height, weight, stage of puberty, X-ray for bone age and transabdominal ultrasounds were performed on all girls. Higher chronological age, bone age and increase in breast stage significantly predicted higher MOV (P < 0.001) and higher uterine length (P < 0.001). The MOV, uterine length and FCR are positively correlated with chronological age, bone age, height, weight and breast staging. Data from present study may be useful in screening cases of precocious puberty and other disorders that may need further evaluation.  相似文献   
87.
This study examines union certification elections in hospitals from October 1994 to September 1997. Results indicate that union win rates were significantly higher in single-union elections and larger bargaining units. On the other hand, union win rates were significantly lower in church-related hospitals and hospitals that belonged to a health care system or had higher payroll costs. Unions also appeared to win elections at a higher rate in this period than in the past.  相似文献   
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89.
The experiments were conducted to identify the toxin that produces pulmonary oedema in Mesobuthus tamulus (BT) envenomed animals. Crude BT venom was subjected to Sephadex gel filtration (G-75) and the fractions were screened for optical density (OD), neurotoxicity (prolongation of compound action potential in frog sciatic nerve) and lethality. All these parameters exhibited a peak between 54-94 ml eluates. Fractions of this peak were pooled (SP) and loaded on to carboxymethyl cellulose column. The column was then eluted with increasing buffer concentrations at constant pH and temperature. Eluates were screened for neurotoxicity and OD. Four peaks of neurotoxic activity (T1-T4) were detected. T2 and T3 were lethal whereas T1 and T4 were non-lethal. T2 exhibited mainly neurotoxicity and failed to augment phenyldiguanide (PDG)-induced reflex response or to produce pulmonary oedema. T3 was having minimal neurotoxic actions but augmented PDG-reflex and produced pulmonary oedema. The effects of T3 persisted even after dialysis with 8 kDa cut-off filter but not those of T2. The T3 effects resembled toxic manifestations of BT venom and were blocked by aprotinin pre-treatment. T3 demonstrated a band at approximately 100 kDa in SDS-PAGE. The results demonstrate the presence of a lethal, high molecular weight, pulmonary oedema producing toxin in BT venom.  相似文献   
90.
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