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101.
J J Asca?o H Frierson C A Moskaluk J C Harper F Roviello C E Jackson W El-Rifai C Vindigni P Tosi S M Powell 《Modern pathology》2001,14(10):942-949
Loss of the cell adhesion molecule E-cadherin has been observed in a variety of human carcinomas, and germline E-cadherin mutations have been found in several familial cases of diffuse gastric cancer. We sought to determine the prevalence and nature of E-cadherin alterations in "sporadic" gastric carcinomas. We performed comprehensive sequencing of the coding region, loss of heterozygosity (LOH) analysis, and immunohistochemical protein expression determination on 40 sporadic gastric adenocarcinomas. In total, 7 of 25 diffuse-type cancers harbored genetic alterations in the E-cadherin gene. Novel mutations predicted to significantly compromise protein function were found within 4 of these cancers, 2 of which harbored alterations resulting in biallelic inactivation of the gene product. Three diffuse cancers failed to amplify Exon 8 of E-cadherin, suggesting the presence of a homozygous abnormality. Notably, one germline E-cadherin mutation was also identified within these "sporadic" diffuse cancers. Significant gene mutations were not found in the 14 intestinal-type or histologically mixed cancer. Immunohistochemistry revealed aberrant or negative protein expression in seven diffuse-type tumors, four of which correlated with the genetic alterations. Both diffuse and intestinal-type tumors exhibited low rates of LOH, suggesting that allelic loss at the locus is not a common mechanism for E-cadherin inactivation during gastric tumorigenesis. Our observations suggest that inactivation of the E-cadherin gene occurs only in a subset of diffuse-type gastric cancers, as the majority of cases did not contain genetic alterations or identifiable protein abnormalities. Germline E-cadherin alterations, although rare, may underlie some diffuse gastric cancer cases that have important biologic and practical implications 相似文献
102.
DL?MagerEmail author AD?Haffajee PM?Devlin CM?Norris MR?Posner JM?Goodson 《Journal of translational medicine》2005,3(1):27
Background
The purpose of the present investigation was to determine if the salivary counts of 40 common oral bacteria in subjects with an oral squamous cell carcinoma (OSCC) lesion would differ from those found in cancer-free (OSCC-free) controls. 相似文献103.
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106.
T al-Shawaf A Nolan J Harper P Serhal I Craft 《Human reproduction (Oxford, England)》1991,6(3):365-366
Cryopreserved spermatozoa from men having treatment for lymphoma or testicular tumour have been reported to function sub-optimally. We report on three successful pregnancies following gamete intra-Fallopian transfer (GIFT) using such cryopreserved sperm samples. In one case, ovum donation was required since the woman had premature ovarian failure. 相似文献
107.
N. Y. Calingasan S. E. Gandy H. Baker K. F. Sheu J. D. Smith B. T. Lamb J. D. Gearhart J. D. Buxbaum C. Harper D. J. Selkoe D. L. Price S. S. Sisodia G. E. Gibson 《The American journal of pathology》1996,149(3):1063-1071
Experimental thiamine deficiency (TD) is a classical model of a nutritional deficit associated with a generalized impairment of oxidative metabolism and selective cell loss in the brain. In rats, TD-induced cell degeneration is accompanied by an accumulation of amyloid precursor protein (APP)/amyloid precursor-like protein 2 (APLP2) immunoreactivity in abnormal neurites and perikarya along the periphery of, or scattered within, the lesion. Prompted by these data and our previous findings of a genetic variation in the development of TD symptoms, we extended our studies to mice. C57BL/6, ApoE knockout, and APP YAC transgenic mice received thiamine-deficient diet and pyrithiamine injections. Unlike rats, APP/APLP2-immunoreactive neurites in all strains of mice were sparsely scattered within damaged areas and did not delimit the thalamic lesion. In addition, abnormal clusters of intensely immunoreactive neurites occurred only in areas of damage including the thalamus, mammillary body, and inferior colliculus. The clusters appeared as either irregular clumps or round or oval rosettes that strikingly resembled the neuritic component of Alzheimer amyloid plaques. However, immunostaining using various antisera to synthetic amyloid beta-protein (A beta 1-40) and thioflavine S histochemistry failed to show evidence of a component of A beta Neither APP/APLP2-immunoreactive clusters nor amyloid plaques were observed in the brain from patients with Wernicke-Korsakoff syndrome, the clinical manifestation of TD in man. Our results demonstrate species (i.e., genetic) differences in the response to TD-induced damage and support a role for APP and APLP2 in the response to brain injury. This is the first report that chronic oxidative deficits can lead to this novel pathology. 相似文献
108.
Moore GE Ruangvutilert P Chatzimeletiou K Bell G Chen CK Johnson P Harper JC 《European journal of human genetics : EJHG》2000,8(3):223-228
In man high levels of aneuploidy are seen in spontaneous abortions. Very few autosomal trisomies survive to birth, the three most common being those for chromosome 13, 18 and 21 giving rise to the syndromes named Patau, Edwards and Down respectively. Since the majority of these spontaneously abort, what makes the survivors different from the aborters? Could it be that they have tissue specific mosaicism with the additional normal cell line supporting survival? In this study fluorescence in situ hybridisation was used as a convenient way to detect trisomy in interphase cells. To study the level of mosaicism across gestation, different tissues from 21 trisomic foetuses were analysed using probes for chromosome 13, 18, 21, X and Y. Two trisomy 18 foetuses exhibited mosaicism. Two others, one trisomy 13 and one trisomy 18 had mosaic placentas. There was no clear association between the limited mosaicism seen and severity of the phenotype. We conclude that at least for this sample set, tissue-specific mosaicism was not likely to be responsible for potential survival to birth. 相似文献
109.
The effectiveness of a treatment protocol for male lower urinary tract symptoms in general practice: a practical randomised controlled trial
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Roelf JC Norg Kees van de Beek Piet JM Portegijs CP Onno van Schayck J Andr Knottnerus 《The British journal of general practice》2006,56(533):938-944
BACKGROUND: Randomised controlled trials have shown the efficacy of several treatment modalities for lower urinary tract symptoms (LUTS) in selected populations. The effectiveness in daily practice has hardly been investigated, especially in primary care and is dependent on choices between all possible treatment options and best investigated in a comprehensive study, including all treatment modalities (watchful waiting, alpha-blockers, 5-alpha-reductase inhibitors, and surgery). AIM: Assessment of the effectiveness of a comprehensive treatment protocol for LUTS in primary care. DESIGN OF STUDY: Randomised controlled trial. SETTING: Fourteen general practices in the Netherlands. METHOD: Intervention: treatment protocol based on a formalised expert opinion. Control condition: usual care. Study population: 208 subjects with moderate to severe LUTS (IPSS > or =8, median = 13). OUTCOME MEASURES: symptom severity (IPSS [International Prostate Symptom Score]), bother score (Dan-PSS [Danish Prostate Symptom Score]), and maximum urinary flow (Q(max)); incidence of acute urinary retention and urinary tract infections. RESULTS: In the intervention group markedly more subjects used an alpha-blocker at end of follow-up than in the usual care group (24% versus 6%). No significant differences were found between intervention and control group in IPSS, Q(max) or Dan-PSS. CONCLUSION: alpha-blockers and watchful waiting are the most frequent treatment modalities for LUTS in primary care. Our study showed no evidence that a protocol using well-defined indications for all possible treatment modalities based on a formalised expert opinion procedure has added value. Based on our results, we cannot recommend a broadening of the indication for alpha-blockers, which, however, seems to be the current trend. 相似文献
110.