Parkinson disease (PD) is a neurodegenerative disorder characterized by loss of midbrain dopaminergic (DA) neurons. ES cells are currently the most promising donor cell source for cell-replacement therapy in PD. We previously described a strong neuralizing activity present on the surface of stromal cells, named stromal cellderived inducing activity (SDIA). In this study, we generated neurospheres composed of neural progenitors from monkey ES cells, which are capable of producing large numbers of DA neurons. We demonstrated that FGF20, preferentially expressed in the substantia nigra, acts synergistically with FGF2 to increase the number of DA neurons in ES cell-derived neurospheres. We also analyzed the effect of transplantation of DA neurons generated from monkey ES cells into 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-treated (MPTP-treated) monkeys, a primate model for PD. Behavioral studies and functional imaging revealed that the transplanted cells functioned as DA neurons and attenuated MPTP-induced neurological symptoms. IntroductionParkinson disease (PD) is a neurodegenerative disorder characterized by the loss of midbrain dopaminergic (DA) neurons, with subsequent reductions in striatal dopamine levels. While initial pharmacological treatment with L-dihydroxyphenylalanin (L-DOPA) can attenuate symptoms, the efficacy of this treatment gradually decreases over time. The development of motor complications then requires additional treatments, including deep brain stimulation and fetal DA neuron transplantation (1-3). Both studies of animal models and clinical investigations have shown that transplantation of fetal DA neurons can produce symptomatic relief (4-8). The technical and ethical difficulties in obtaining sufficient and appropriate donor fetal brain tissue, however, have limited the application of this therapy.ES cells are self-renewing, pluripotent cells derived from the inner cell mass of the preimplantation blastocyst. These cells have many of the characteristics required of a cell source for cell-replacement therapy, including proliferation and differentiation capacities (9). We previously discovered that a strong neuralizing activity, which we called stromal cell-derived inducing activity (SDIA), is present
Objective -To develop and validate a set of practical prediction tools that reliably estimate the outcome of subarachnoid haemorrhage from ruptured intracranial aneurysms (SAH).Design -Cohort study with logistic regression analysis to combine predictors and treatment modality.Setting -Subarachnoid Haemorrhage International Trialists' (SAHIT) data repository, including randomised clinical trials, prospective observational studies, and hospital registries.Participants -Researchers collaborated to pool datasets of prospective observational studies, hospital registries, and randomised clinical trials of SAH from multiple geographical regions to develop and validate clinical prediction models.Main outcome measure -Predicted risk of mortality or functional outcome at three months according to score on the Glasgow outcome scale.Results -Clinical prediction models were developed with individual patient data from 10 936 patients and validated with data from 3355 patients after development of the model. In the validation cohort, a core model including patient age, premorbid hypertension, and neurological grade on admission to predict risk of functional outcome had good discrimination, with an area under the receiver operator characteristics curve (AUC) of 0.80 (95% confidence interval 0.78 to 0.82). When the core model was extended to a "neuroimaging model," with inclusion of clot volume, aneurysm size, and location, the AUC improved to 0.81 (0.79 to 0.84). A full model that extended the neuroimaging model by including treatment modality had AUC of 0.81 (0.79 to 0.83). Discrimination was lower for a similar set of models to predict risk of mortality (AUC for full model 0.76, 0.69 to 0.82). All models showed satisfactory calibration in the validation cohort. Conclusion -The prediction models reliably estimate the outcome of patients who were managed in various settings for ruptured intracranial aneurysms that caused subarachnoid haemorrhage. The predictor items are readily derived at hospital admission. The web based SAHIT prognostic calculator (http://sahitscore.com) and the related app could be adjunctive tools to support management of patients. IntroductionSubarachnoid haemorrhage from a ruptured intracranial aneurysm (SAH) is a relatively uncommon but severe subtype of stroke that is associated with a sudden dramatic onset in otherwise apparently healthy individuals and often results in poor outcomes. On average, a third of affected individuals do not survive; at least one in five of those who do survive are unable to regain functional independence.1 SAH is unlike the more common ischaemic stroke as it affects younger adults (median age 55) and therefore results in disproportionately many years of lost productive life.1 2 Predicting the outcome of this condition can be challenging given the considerable heterogeneity in the characteristics of affected individuals and their clinical course and variability in morphology of the aneurysm. Reliance on clinical intuition alone might be insufficient for accur...
Parkinson disease (PD) is a neurodegenerative disorder characterized by loss of midbrain dopaminergic (DA) neurons. ES cells are currently the most promising donor cell source for cell-replacement therapy in PD. We previously described a strong neuralizing activity present on the surface of stromal cells, named stromal cell–derived inducing activity (SDIA). In this study, we generated neurospheres composed of neural progenitors from monkey ES cells, which are capable of producing large numbers of DA neurons. We demonstrated that FGF20, preferentially expressed in the substantia nigra, acts synergistically with FGF2 to increase the number of DA neurons in ES cell–derived neurospheres. We also analyzed the effect of transplantation of DA neurons generated from monkey ES cells into 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine–treated (MPTP-treated) monkeys, a primate model for PD. Behavioral studies and functional imaging revealed that the transplanted cells functioned as DA neurons and attenuated MPTP-induced neurological symptoms
The differentiation of dopaminergic (DA) neurons from mouse embryonic stem cells (ESCs) can be efficiently induced, making these neurons a potential source for transplantation as a treatment for Parkinson's disease, a condition characterized by the gradual loss of midbrain DA neurons. One of the major persistent obstacles to the successful implementation of therapeutic ESC transplantation is the propensity of ESC-derived grafts to form tumors in vivo. To address this problem, we used fluorescence-activated cell sorting to purify mouse ESC-derived neural precursors expressing the neural precursor marker Sox1. ESCderived, Sox1 ؉ cells began to express neuronal cell markers and differentiated into DA neurons upon transplantation into mouse brains but did not generate tumors in this site. In contrast, Sox1 ؊ cells that expressed ESC markers frequently formed tumors in vivo. These results indicate that Sox1-based cell sorting of neural precursors prevents graftderived tumor formation after transplantation, providing a promising strategy for cell transplantation therapy of neurodegenerative disorders.
Rho-GTPase has been implicated in the apoptosis of many cell types, including neurons, but the mechanism by which it acts is not fully understood. Here, we investigate the roles of Rho and ROCK in apoptosis during transplantation of embryonic stem cell-derived neural precursor cells. We find that dissociation of neural precursors activates Rho and induces apoptosis. Treatment with the Rho inhibitor C3 exoenzyme and/or the ROCK inhibitor Y-27632 decreases the amount of dissociation-induced apoptosis (anoikis) by 20-30%. Membrane blebbing, which is an early morphological sign of apoptosis; cleavage of caspase-3; and release of cytochrome c from the mitochondria are also reduced by ROCK inhibition. These results suggest that dissociation of neural precursor cells elicits an intrinsic pathway of cell death that is at least partially mediated through the Rho/ROCK pathway. Moreover, in an animal transplantation model, inhibition of Rho and/or ROCK suppresses acute apoptosis of grafted cells. After transplantation, tumor necrosis factor-alpha and pro-nerve growth factor are strongly expressed around the graft. ROCK inhibition also suppresses apoptosis enhanced by these inflammatory cytokines. Taken together, these results indicate that inhibition of Rho/ROCK signaling may improve survival of grafted cells in cell replacement therapy.
Notch signaling inhibits hair cell differentiation, based on studies on mice deficient in Notch signaling-related genes and its downstream genes. However, the precise mechanisms of this inhibition are unknown because it is difficult to control the timing and duration of the suppression of Notch signaling. Here, we developed a novel in vitro culture and analysis method for mouse fetal cochleae and examined the roles of Notch signaling by its reversible inhibition through the use of Notch signaling inhibitors of gamma-secretase and TNF-alpha-converting enzyme. Notch inhibition with Notch signaling inhibitor treatment increases the number of cochlear hair cells, as observed in gene deletion experiments. We elucidated that this increase is regulated by the dichotomy between hair cells and supporting cells from common progenitors. We also propose other roles of Notch signaling in cochlear development. First, Notch signaling arrests the cell cycle of the cochlear epithelium containing putative hair cells and supporting cell progenitors because Notch inhibition with inhibitor treatment increases the number of 5-bromo-2'-deoxyuridine (BrdU)-positive cells that can differentiate into hair cells or supporting cells. Second, Notch signaling is required for the induction of Prox1-positive supporting cells. Third, Notch signaling is required for the maintenance of supporting cells.
Transplantation of stem cells has the possibility of restoring neural functions after stroke damage. Therefore, we transplanted neuronal progenitors generated from monkey embryonic stem (ES) cells into the ischemic mouse brain to test this possibility. Monkey ES cells were caused to differentiate into neuronal progenitors by the stromal cell-derived inducing activity method. Focal cerebral ischemia was induced by occluding the middle cerebral artery by the intraluminal filament technique. The donor cells were transplanted into the ischemic lateral striatum at 24 h after the start of reperfusion. The cells transplanted into the ischemic brain became located widely around the ischemic area, and, moreover, the transplanted cells differentiated into various types of neurons and glial cells. Furthermore, at 28 days after the transplantation, over 10 times more cells in the graft were labeled with Fluorogold (FG) by stereotactic focal injection of FG into the anterior thalamus and substantia nigra on the grafted side when compared with the number at 14 days. From these results we confirmed the survival and differentiation of, as well as network formation by, monkey ES-cell-derived neuronal progenitors transplanted into the ischemic mouse brain.
TSH, T4, and T3 were measured by radioimmunoassay in plasma samples obtained from 77 young adult male and 114 female rats fed a Purina high-iodine diet and maintained in an isolated room, 2-4/cage, at 24 +/- 1 C with light from 0600-1800 h. In one experiment, 7 male and 7 female rats were decapitated every 3 h for 30 consecutive h and trunk blood was collected. There was a clear nyctohemeral rhythm of plasma TSH in both sexes characterized by a zenith at 1200 h and a nadir between 1800 and 2100 h. The plasma TSH cycle was approximately 180 degrees out of phase and negatively correlated (P less than .05) with that of plasma corticosterone (B) in both sexes. Although glucocorticoids have been reported to suppress TSH secretion, there was no causal relationship between plasma B and TSH in our experiments since the TSH cycles were normal in chronically adrenalectomized rats. Normal TSH cyclicity was not observed in severely iodine-deficient rats with extremely high plasma TSH levels although the nyctohemeral B rhythm was normal. Plasma TSH was approximately twice as high in males as in females (overall mean +/- SE: M = 149 +/- 11, F = 81 +/- 7 muU/ml, p less than 0.001). There was no significant difference (P greater than 0.05) in plasma TSH at different stages of the estrous cycle. Plasma T4 was slightly, but significantly, higher in males than females (overall mean +/- SE: M = 6.4 +/- 0.1, F = 6.0 +/- 0.1 mug/100 ml; P less than 0.001), while T3 was higher in females than in males (overall mean +/- SE: M = 69.5 +/- 1.7, F = 80.3 +/- 2.1 ng/100 ml; P less than 0.001). No significant nyctohemeral rhythm was observed in plasma T4 or T3 in either sex. These observations indicate that: 1) There is a nyctohemeral rhythm of plasma TSH which is independent of plasma B fluctuations and not associated with proportional changes in plasma thyroid hormones. 2) A sustained high rate of TSH secretion abolishes the normal nyctohemeral plasma TSH rhythm. 3) There are significant differences in plasma concentrations of TSH, T4, and T3 between male and female rats.
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