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Occhiuto F Palumbo DR Samperi S Zangla G Pino A De Pasquale R Circosta C 《Phytotherapy research : PTR》2009,23(2):192-196
Oxidative stress-induced neuronal cell death has been implicated in different neurological disorders and neurodegenerative diseases such as Alzheimer's disease and Parkinson's. Using the Alzheimer's disease-associated hydrogen peroxide (H(2)O(2)), we investigated the neuroprotective efficacy of a natural mixture of phytoestrogenic isoflavones (genistein, daidzein, biochanin A and formononetin) from Trifolium pratense L. (Red clover) against oxidative stress-induced cell death in human cortical cell line HCN 1-A maintained in culture. Neuronal viability was determined by MTT or trypan blue test and neuronal integrity by morphological analysis.The results obtained indicate that exposure of HCN 1-A cell cultures to hydrogen peroxide resulted in a concentration-dependent decrease in neuron viability. Concentration of H(2)O(2) ranging from 50 to 200 microg/ml were toxic to these cultures. A 24-hour pretreatment with 0.5, 1 and 2 microg/ml isoflavones extract significantly increased cell survival as evidenced by MTT or trypan blue test and significantly prevented the morphological disruption caused by H(2)O(2) as shown by microscopical inspection, indicating that neurons treated with isoflavones were protected from the cell death induced by H(2)O(2) exposure. These findings imply that the neuroprotective effect of isoflavones extract is partly associated with its antioxidant activity. Further, results of these investigations indicate that although isoflavones extract exert a neuroprotective effect, it do not promoted cortical neuron process outgrowth. 相似文献
6.
Megakaryocytic Progenitors Can Be Generated Ex Vivo and Safely Administered to Autologous Peripheral Blood Progenitor Cell Transplant Recipients 总被引:9,自引:1,他引:8
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G Zamboni G Franzin F Bonetti A Scarpa M Chilosi R Colombari F Menestrina M Pea C Iacono G Serio 《The American journal of surgical pathology》1990,14(8):703-713
We report the clinicopathologic, immunohistochemical, and ultrastructural features of three small-cell neuroendocrine carcinomas of the ampullary region of the duodenum. All patients were men; their ages were 51, 62, and 66 years. The therapy consisted of pancreatoduodenectomy. All patients died of the disease; median survival was 10 months from the diagnosis. The histological appearance was identical to pulmonary and extrapulmonary small-cell carcinoma. The neuroendocrine differentiation was demonstrated ultrastructurally by the presence of dense-core granules, and by the positive immunoreaction for neuron-specific enolase and Leu-7 in each case. One case expressed a focal positivity for chromogranin A (PHE-5) and argyrophilic granules. The same case showed the presence of neurofilaments on frozen material. Neurofilament proteins could not be demonstrated in any case in paraffin sections. Neoplastic cells exhibited cytoplasmic immunostaining for cytokeratins (CAM 5.2) in all cases. In one case, a large number of neoplastic cells (60-70%) exhibited nuclear Ki-67 positivity. We postulate that the disease's histogenesis was from epithelial stem cell expressing both epithelial and neuroendocrine characteristics. The clinical behavior of small-cell neuroendocrine carcinomas of the ampullary region appears to be extremely aggressive, with early metastases and fatal outcome. 相似文献
8.
Calogero Iacono Giuseppe Verlato Giuseppe Zamboni Aldo Scarpa Ettore Montresor Paola Capelli Luca Bortolasi Giovanni Serio 《Journal of gastrointestinal surgery》2007,11(5):578-588
Objective To evaluate the prognostic significance of different clinico-pathological and molecular factors, and to compare survival after
standard and extended pancreaticoduodenectomy (PD) in ampulla of Vater adenocarcinoma (AVAC).
Summary Background Data There are discordant data on factors affecting prognosis, and hence therapeutic choices, in AVAC.
Patients and Methods Clinical-pathological factors were evaluated in 59 patients, subjected to PD for AVAC; in 42 subjects information on chromosome
17p and 18q allelic losses (LOH) and microsatellite instability (MSI) was also available. The association between survival
and type of PD was investigated in the 25 patients operated between 1990 and 2001 (16 standard and nine extended).
Results The overall 5- and 10-year tumor-related survival rates were 46% and 33%, respectively. Sixteen patients had T-stages 1–2,
14 T-stage 3, and 29 T-stage 4 cancers. Chromosome 17p and 18q LOH were detected in 23 (55%) and 15 cases (36%), respectively,
and in 12 cases (29%) coexisted. Five cases were MSI-positive (12%). At univariate analysis, poor survival was associated
with cancer ulceration (P = 0.051), poor differentiation (P = 0.008), T-stage 4 (P < 0.001), nodal metastases (P = 0.004), chromosome 17p (P < 0.001) and 18q LOH (P = 0.002), and absence of MSI (P = 0.009). At multivariate analysis, only T-stage (P = 0.002) and 17p LOH (P = 0.001) were independent predictors of survival. All patients with MSI-positive cancers were long-survivors (>12 yrs), whereas
only 30% of MSI-negative cancer patients survived at 5 years. Extended pancreaticoduodenectomy was associated with a 3-year
disease-related survival higher than standard resection (83% vs 31%; P = 0.018).
Conclusion MSI and chromosome 17p status allow to better define prognosis within ampullary cancers at the same stage. Surgery alone resulted
curative in MSI-positive cancer patients, whereas it was inadequate in patients showing allelic losses, who might benefit
from adjuvant therapy. In this observational study, extended PD was associated with increased survival compared to standard
procedures.
Presented at the 2006 Annual Meeting of the American Hepato-Pancreato-Biliary Association, Miami Beach, Florida, March 9–12,
2006 相似文献
9.
Family needs after traumatic brain injury: a factor analytic study of the Family Needs Questionnaire
The present investigation examined the empirical and theoretical validity of an instrument developed to assess family members' perceptions of needs following the brain injury of a relative. The Family Needs Questionnaire FNQ consists of 40 items reflecting commonly reported family needs. The development of the items was based on the literature describing family reactions to brain injury and other medical disabilities. A principal-components factor analysis was executed based on the FNQ responses of 178 family members. A six-factor solution was selection as the best fit for the data, yielding the following independent subscales: 1 Need for Health Information; 2 Need for Emotional Support; 3 Need for Instrumental Support; 4 Need for Professional Support; 5 Need for a Support Network; and 6 Need for Involvement with Care. Further analysis indicated at least adequate internal reliability for each scale. Overall, the measure appears to offer unique information relevant to family members' needs after brain injury. 相似文献
10.
Marina Quartu Maria Pina Serra Annalisa Manca Paolo Follesa Rossano Ambu Marina Del Fiacco 《International journal of developmental neuroscience》2003,21(6):309-320
The immunohistochemical occurrence of the high affinity neurotrophin (NT) receptors trkA, trkB, and trkC is shown in the pre-term newborn, infant, and adult human post-mortem cerebellum. Immunoreactive neuronal perikarya and processes were observed in all specimens examined, where they appeared unevenly distributed in the cerebellar cortical layers and deep nuclei, and showed regional differences among cerebellar lobules and folia. The trk receptor-antibodies, tested by Western blot on human cerebellum homogenates, revealed multiple immunoreactive bands for trkA and single bands for trkB and trkC. The results obtained show the tissue localization of the trk receptor-like immunoreactivity in the human cerebellum from prenatal to adult age. The analysis for codistribution of the receptors with the relevant ligand and among the receptors in discrete cortical and deep nuclei tissue fields shows a wide variety of conditions, from a good similarity in terms of type and density of labeled structures, to a lack of correspondence, and suggests the possibility of colocalization of trk receptors with the relevant neurotrophin and among them in the cerebellar cortex. These results sustain the concept that the neurotrophin trophic system participates in the development, differentiation, and maintenance of the human cerebellar connectivity and support the possibility of a multifactorial trophic support for the neurotrophins through target-derived and local mechanisms. 相似文献