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1.
Detailed analyses of the neuropathologic changes in the cerebralcortex of elderly individuals and Alzheimer's disease patientshave demonstrated that certain components of the neocorticaland hippocampal circuits are likely to be selectively vulnerable.Based on the distribution of neurofibrillary tangles (NFTs)and senile plaques, it has been proposed that a global cortico-corticaldisconnection leads to the loss of integrated functions observedin Alzheimer's disease. In order to investigate the distributionof lesions associated with aging as well as with the earliestsymptoms of senile dementia, we performed a quantitative neuropathologicavaluation of a large series of elderly patients representingthe entire autopsy population for the year 1989 from a geriatrichospital. Among the 145 cases quantitatively assessed, therewere 102 nondemented patients, 33 patients presenting clinicallywith globally intact intellectual function but early signs ofimpairment of specific cognitive functions, and 10 cases withsenile dementia of the Alzheimer type. All of the cases hadNFTs in layer II of the entorhinal cortex, regardless of theirclinical diagnosis, and most cases had some NFTs in the CA1field of the hippocampus. Severe pathologic changes within theinferior temporal neocortex were observed only in the dementedcases. The extent of amyloid deposition was not correlated withthe clinical diagnosis and seemed to be present in the neocorticalareas earlier than in the hippocampal formation. Also, severalcases contained NFTs without amyloid deposition, but amyloidnever occurred without NFTs. These results suggests that involvementof certain structures within the hippocampal formation is aconsistent feature of aging. Thus, involvement of the hippocampalformation may be a necessary, but not sufficient, conditionfor the clinical expression of dementia, which is likely tobe more closely related to the progressive degeneration of selectneuronal populations in the neocortex.  相似文献   
2.
This study was sought to evaluate the relationship between Her-2 protein expression, cellular localization, gene amplification, and other clinicopathologic parameters in colorectal carcinomas. Her-2 protein expression and gene amplification were assessed in paraffin sections from 106 primary colorectal adenocarcinoma cases using immunohistochemistry and fluorescence in situ hybridization. Both membranous and cytoplasmic immunostaining was evaluated. The results were correlated with each other and with tumor grade, stage, and overall survival. Membranous and cytoplasmic protein expression was identified in 6 (5.6%) and 13 (12.26%) cases, respectively. Gene amplification was detected in 4 (3.7%) cases. There was a high concordance between membranous protein expression and gene amplification (kappa=0.791). No apparent association with any of the clinicopathologic parameters was identified. Membranous Her-2 protein expression and gene amplification are encountered in a small subset of colorectal carcinomas and are highly concordant events. Cytoplasmic protein expression might be either artifactual or it might represent a cross-reacting protein or a precursor form of the mature protein.  相似文献   
3.
Colorectal cancer is a disease affecting mainly older people, a fact that is becoming more apparent with the global population aging. However, this patient group is more likely to be subjected to suboptimal treatment due to a number of factors, but most commonly as a result of the physician’s weakness to recognize those fit for the full spectrum of cancer therapy. In this regard, clinical screening tests, such as the Comprehensive Geriatric Assessment, can be invaluable in guiding treatment decisions. Fluoropyrimidine-based adjuvant chemotherapy clearly confers a survival advantage in older individuals with node-positive disease; however, the benefit from the administration of oxaliplatin-based regimens is less clear. Palliative chemotherapy also has an important role in managing metastatic disease, and with the use of novel targeted agents it can potentially prolong survival and improve quality of life. The management of rectal cancer in this population can present a challenge, since it appears that the optimal treatment of chemoradiation followed by total mesorectal excision can be applied in select few. Indeed, the morbidity and mortality rates in older people treated with these combined modalities can be too high, guiding many physicians to opt for more conservative approaches, directed at providing palliation and local control, especially in those with limited life expectancy. In conclusion, in order to provide the best care in an older colorectal cancer patient, we need to individualize our approach, selecting the right patient for the right treatment.  相似文献   
4.
Diabetic nephropathy is the most serious problem among current issues in nephrology, as 40% of the cases of end-stage renal disease are due to this entity. The close relationship between type 2 diabetes and hypertension makes the problem even more severe. The knowledge of the intrarenal effects of angiotensin II and the greater effect of angiotensin converting enzyme inhibitors (ACEI) on reducing albuminuria suggested in the past a trend toward preferable use of these drugs in diabetic nephropathy. The first relevant clinical trials yielded rather poor conclusions because of lack of blind randomization and short duration. Subsequent double-blind studies with adequate numbers of patients and sufficient duration underlined the importance of blood pressure (BP) control as well as the rather poor response of diabetic nephropathy to any treatment. In most of these studies, the changes in albuminuria or microalbuminuria were a substitute end point for the renal function. Three clinical trials using angiotensin II receptor blockers (ARB), planned specifically to monitor the progression of renal damage, have been recently published. They showed better renal protection by ARB, as compared with placebo or calcium channel blockers (CCB), beyond or independently of the BP reduction. Nevertheless, these recent trials, like the previous ones with similar results, invariably demonstrate slightly better control of BP in the groups of the active drug. Another issue is that the vast majority of the patients need so many nonstudy drugs to keep their pressure under control, that the isolation of advantageous effects of certain drugs seems unrealistic.  相似文献   
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A 79-year-old patient with neuropathologically confirmed Alzheimer’s disease (AD) presented with a selective environmental reduplicative paramnesia (RP), the belief that one or more environments exist simultaneously in two or more physical locations. Clinical presentation and neuropathological examination revealed an atypical form of AD. High neurofibrillary tangle densities were observed in the frontal and temporal association cortex, whereas the parietal and entorhinal cortex, as well as the hippocampus, were nearly spared. These findings are compared to those reported in frontal and frontotemporal variants of AD and discussed in the light of current anatomoclinical models for environmental RP.  相似文献   
7.
BACKGROUND: p53 protein is regarded as a valuable prognostic marker in cancer with a potential use as a molecular target. Here, we sought to determine the prognostic value of p53 in ovarian cancer using a novel method of compartmentalized in situ protein analysis. PATIENTS AND METHODS: A tissue array composed of 141 advanced stage ovarian cancers uniformly treated was constructed. For evaluation of p53 protein expression, we used an immunofluorescence-based method of automated in situ quantitative measurement of protein analysis (AQUA). RESULTS: High nuclear p53 expression levels were associated with better outcome for overall survival (OS) (P = 0.0023) and disease-free survival (P = 0.0338) at 5-years. High cytoplasmic p53 expression levels were associated with better outcome for OS (P = 0.0002). In multivariable analysis, high nuclear and high cytoplasmic p53 level with International Federation of Gynecology and Obstetrics (FIGO) stage were the most significant predictor variables for OS and high nuclear p53 level with FIGO stage were the significant predictor variables for disease-free survival. CONCLUSIONS: Assessment of the prognostic value of p53 protein levels using conventional immunohistochemistry is limited by the nonquantitative nature of the method. AQUA provides precise estimation of p53 protein levels and was able to elucidate the association of p53 protein levels and ovarian cancer prognosis.  相似文献   
8.
The entorhinal cortex and hippocampus are the first cortical regions to be affected by the degenerative cellular process that leads to Alzheimer disease (AD) and display a limited degree of neuronal alterations in normal aging. Several quantitative studies have reported a substantial loss of neurons in these regions and a parallel increase in the number of neurofibrillary tangles (NFTs). However, accurate quantitative data on the dynamics of NFT formation are lacking. Here, we performed a stereologic assessment of the proportions of intracellular and extracellular (ghost) NFTs (iNFTs and eNFTs, respectively) and unaffected neurons in layer II of the entorhinal cortex and in the pyramidal cell layer of the CA1 field of the hippocampus in elderly control cases compared to cases with varying degrees of cognitive dysfunction. The data revealed differential rates of formation of iNFTs and eNFTs between the 2 regions and confirmed the presence of a severe disease-associated, but not age-related, neuronal loss. They also revealed that large numbers of neurons may persist either unaffected or in a transitional stage of NFT formation until the late stages of AD progression. These neurons with viability potential constitute 73% of the total numbers of profiles in layer II of the entorhinal cortex and 77% in the CA1 field in cases with a Clinical Dementia Rating score of 3. Whereas it is not possible in the present study to assess how functional such neurons with altered physiology might be, it is nonetheless likely that these transitional neurons open new options for potential therapeutic interventions aimed at protecting neurons vulnerable to neurofibrillary degeneration.  相似文献   
9.
Cornelia de Lange syndrome (CDLS) is a rare multisystemic malformative syndrome of uncertain etiology characterized by severe psychomotor and mental retardation. Here we report the neuropathological analysis of a 35-year-old patient who displayed the classical clinical symptomatology of CDLS. A congenital dysgenesis of the brain was evident including abnormal convolution patterns of the cerebral gyri, frontal lobe hypoplasia and focal lack of myelination in layers V and VI of the left temporal cortex. In addition, there were vascular scars in the CA2-3 region of the left hippocampus and in the right parietal cortex as well as a few neurofibrillary tangles in the CA fields of the hippocampus and in the entorhinal cortex. In contrast to previous reports, there were no midline cerebral dysgenesis and no ectopic neuron formations in the present case. Neuronal loss and gliosis were also absent in all cortical and subcortical areas. Our observations suggest that the main neurodevelopmental deficits in CDLS occur during the late phase of gestation. Conversely, early neurodegenerative changes are not characteristic of CDLS. In the light of previous studies in younger CDLS patients, the vascular and degenerative lesions observed in the present case may be secondary to his severe congenital heart abnormalities and self-injury behavior, respectively.  相似文献   
10.
BACKGROUND: The conversion of mild cognitive impairment (MCI) to Alzheimer's disease is associated with substantial compromise of neocortical circuits subserving rapid cognitive functions such as working memory. Event-related potential (ERP) analysis is a powerful tool to identify early impairment of these circuits, yet research for an electrophysiological marker of cognitive deterioration in MCI is scarce. Using a "2-back" activation paradigm, we recently described an electrophysiological correlate of working memory activation (positive-negative working memory [PN(wm)] component) over parietal electrodes. METHODS: Ours was a longitudinal study of 24 MCI patients with ERP analysis at inclusion and neuropsychological follow-up after 1 year. We used ERP waveform subtraction analysis between the n-back and control tasks. Analysis of variance (ANOVA) was used to compare electroencephalograph latencies between progressive MCI (PMCI) and stable MCI (SMCI), and univariate regression was used to assess the relationship between neuropsychological measures at baseline and clinical outcome. RESULTS: Thirteen (54%) MCI patients showed PMCI, and 11 (46%) remained stable (SMCI). In SMCI, a PN(wm) component with significantly larger density compared to baseline was identified when subtracting the detection task for both the 1- and 2-back tasks. In contrast, in PMCI, the PN(wm) component was absent in both 1-back and 2-back conditions. Neuropsychological variables and n-back test performance at inclusion did not predict cognitive deterioration 1 year later. CONCLUSIONS: In conjunction with recent functional imaging data, the present results support the notion of an early dysfunction of neural generators within the parietal cortex in MCI. They also reveal that the absence of the PN(wm) component may provide an easily applicable qualitative predictive marker of rapid cognitive deterioration in MCI.  相似文献   
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