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991.
PURPOSE: New, highly efficient technologies used in genomic analysis are described, and their implications for health care are discussed. SUMMARY: The availability of the human genome sequence, in confluence with the ability to affordably package it for analysis, is opening new frontiers in biomedical research. On the horizon, personalized medicine--driven by molecular characterization of disease, genetic analysis of the patient, and information technologies designed to enable health care professionals to leverage these tools--promises to fundamentally transform health care. New genetics technologies, such as high-density microarrays, will fuel this research by providing researchers with the ability to comprehensively access the human genome in all its complexity. Some of the most promising areas for application of genetic information are those where society's current needs are greatest: complex, common disorders, such as cancer and cardiovascular disease; drug interactions; inherited genetic disorders that afflict children; and late-onset conditions for which no cure currently exists. The barriers to using genetic information widely in health care are in many cases not technological or economic, but social and political. CONCLUSION: New technology enables efficient, large-scale analysis of the whole genome, genetic variations, and gene expression. Genomic analysis has profound clinical, economic, and social implications for health care.  相似文献   
992.
First reported prairie dog-to-human tularemia transmission, Texas, 2002   总被引:1,自引:0,他引:1  
A tularemia outbreak, caused by Francisella tularensis type B, occurred among wild-caught, commercially traded prairie dogs. F. tularensis microagglutination titers in one exposed person indicated recent infection. These findings represent the first evidence for prairie-dog-to-human tularemia transmission and demonstrate potential human health risks of the exotic pet trade.  相似文献   
993.
Inadequate health literacy adversely affects health care outcomes and the quality of life of 90 million Americans and costs the health care system dollars 73 billion annually. Current strategies addressing inadequate health literacy primarily target physicians, nurses, and pharmacists but omit the allied health practitioners responsible for providing most patient services. The 2003 Coalition for Allied Health Leadership Health Literacy Project team undertook a survey of allied health professionals and educators to assess their awareness and needs concerning inadequate health literacy. Less than one third of all respondents were aware of the issues surrounding health literacy or that health literacy resources are available or had institutional policy or goals to address health literacy. Brochures and videos were identified most frequently as new resources needed to establish or increase the effectiveness of health literacy awareness programs. The results of this project indicated that there is substantial opportunity to increase awareness of the impact of health literacy, to develop and assess institutional policies toward health literacy, and to create new resources to promote health literacy within the allied health professions. Any approach to improving health literacy must be universal by involving all health care professionals and all patients in the intervention.  相似文献   
994.
Integrins are a class of cell adhesion molecules that participate in cell-cell and cell-substratum interactions and are present on essentially all human cells. The distribution of nine different alpha and beta integrin subunits in human endometrial tissue at different stages of the menstrual cycle was determined using immunoperoxidase staining. Glandular epithelial cells expressed primarily alpha 2, alpha 3, and alpha 6 (collagen/laminin receptors), while stromal cells expressed predominantly alpha 5 (fibronectin receptor). The presence of alpha 1 on glandular epithelial cells was cycle specific, found only during the secretory phase. Expression of both subunits of the vitronectin receptor, alpha v beta 3, also underwent cycle specific changes on endometrial epithelial cells. Immunostaining for alpha v increased throughout the menstrual cycle, while the beta 3 subunit appeared abruptly on cycle day 20 on luminal as well as glandular epithelial cells. Discordant luteal phase biopsies (greater than or equal to 3 d "out of phase") from infertility patients exhibited delayed epithelial beta 3 immunostaining. These results demonstrate similarities, as well as specific differences, between endometrium and other epithelial tissues. Certain integrin moieties appear to be regulated within the cycling endometrium and disruption of integrin expression may be associated with decreased uterine receptivity and infertility.  相似文献   
995.
The pharmacokinetics of the trichothecene mycotoxin, T-2 toxin, were determined in growing gilts and heifers. Following intra-aortal administration in swine and intravenous administration in calves, the disappearance of the parent T-2 toxin followed a 2-compartment open model. Mean elimination phase half-lives were 13.8 and 17.4 min and mean apparent specific volumes of distribution were 0.366 and 0.376 l/kg in swine and calves, respectively. The fraction of T-2 toxin eliminated as parent compound in the urine was negligible. In spite of administration of a lethal oral dose in swine (2.4 mg/kg) and toxic oral doses (up to 3.6 mg/kg) in calves, no parent T-2 toxin was detected in plasma or urine. After intra-aortal administration in swine, tissue concentrations of T-2 toxin were consistently highest in lymphoid organs. Tissue residues of T-2 toxin were rapidly depleted such that, in spite of administration of a potentially lethal intra-aortal dose, no quantifiable T-2 toxin was present in any of the tissues collected at 4 hr after dosing. No T-2 toxin could be detected in liver, even at 1 hr after dosing.  相似文献   
996.
Starting from a novel, achiral 1,3,4-benzotriazepine-based CCK2 receptor antagonist, a process of optimization has afforded further compounds of this type that maintain the nanomolar affinity for recombinant, human CCK2 receptors and high selectivity over CCK1 receptors observed in the initial lead but display more potent inhibition of pentagastrin-stimulated gastric acid secretion in vivo. Moreover, this has largely been achieved without altering their potency at wild-type canine and rat receptors, as judged by their displacement of [125I]-BH-CCK-8S in a radioligand binding assay and by their activity in an isolated, perfused rat stomach bioassay, respectively. 2-(5-Cyclohexyl-1-(2-cyclopentyl-2-oxo-ethyl)-2-oxo-1,2-dihydro-3H-1,3,4-benzotriazepin-3-yl)-N-(3-(5-oxo-2,5-dihydro- [1,2,4]oxadiazol-3-yl)-phenyl)-acetamide (47) was identified as the most effective compound stemming from this approach, proving to be a potent inhibitor of pentagastrin-stimulated gastric acid secretion in rats and dogs by intravenous bolus as well as by enteral administration.  相似文献   
997.
BACKGROUND: Adenovirus-based gene therapy is a promising approach to treat advanced cancers that are resistant to other treatments. However, many primary cells lack the requisite coxsackie-adenovirus receptor (CAR), limiting the in vivo efficacy of gene therapy. Recently, a modified adenovirus that is not dependent on CAR expression for infectivity was developed. We used noninvasive imaging to investigate the in vivo antitumor efficacy of gene therapy using this adenovirus in an animal model of ovarian cancer. METHODS: The adenoviral vectors RGDTKSSTR (CAR-independent) and AdTKSSTR (CAR-dependent) express herpes simplex virus thymidine kinase (TK) for molecular chemotherapy and the human somatostatin receptor subtype 2 (SSTR) for noninvasive nuclear imaging. Subcutaneous or peritoneal human xenograft ovarian cancers were established from highly aggressive SKOV3.ip1 cells in immune-deficient mice. Adenoviral constructs were infected intratumorally or intraperitoneally once a day for 3 days. Control mice received three injections, one per day, of Ad5Luc1, a CAR-dependent adenoviral vector that includes a luciferase marker gene. The somatostatin analogue (99m)Tc-P2045 was used for noninvasive in vivo imaging of RGDTKSSTR that was injected into subcutaneous tumors. For mice with peritoneal tumors, survival was compared among the different treatment groups using Kaplan-Meier analysis with the log-rank statistic. All statistical tests were two-sided. RESULTS: Tumor-associated RGDTKSSTR could be detected 15 days after introduction of the vector. In the subcutaneous model, tumors injected with RGDTKSSTR were statistically significantly smaller than those injected with AdTKSSTR (P<.001). In the intraperitoneal model, mice treated with RGDTKSSTR lived longer (survival at day 45 = 63.6%; 95% confidence interval [CI] = 35.2% to 92.0%) than those treated with AdTKSSTR (survival at day 45 = 0%) or Ad5Luc1 (survival at day 45 = 18.1%; 95% CI = 0.0% to 41.0%). DISCUSSION: RGDTKSSTR shows antitumor efficacy against ovarian cancer in vivo in animal models. The virus can be imaged noninvasively and may have the potential to be a useful agent for treating ovarian cancer.  相似文献   
998.
Treatment of second- and third-line patients with non-small-cell lung carcinoma (NSCLC) with the epidermal growth factor receptor (EGFR) kinase inhibitor erlotinib significantly increased survival relative to placebo. Whereas patient tumors with EGFR mutations have shown responses to EGFR inhibitors, an exclusive role for mutations in patient survival benefit from EGFR inhibition is unclear. Here we show that wild-type EGFR-containing human NSCLC lines grown both in culture and as xenografts show a range of sensitivities to EGFR inhibition dependent on the degree to which they have undergone an epithelial to mesenchymal transition (EMT). NSCLC lines which express the epithelial cell junction protein E-cadherin showed greater sensitivity to EGFR inhibition in vitro and in xenografts. In contrast, NSCLC lines having undergone EMT, expressing vimentin and/or fibronectin, were insensitive to the growth inhibitory effects of EGFR kinase inhibition in vitro and in xenografts. The differential sensitivity of NSCLC cells with epithelial or mesenchymal phenotypes to EGFR inhibition did not correlate with cell cycle status in vitro or with xenograft growth rates in vivo, or with total EGFR protein levels. Cells sensitive to EGFR inhibition, with an epithelial cell phenotype, did exhibit increased phosphorylation of EGFR and ErbB3 and a marked increase in total ErbB3. The loss of E-cadherin and deregulation of beta-catenin associated with EMT have been shown to correlate with poor prognosis in multiple solid tumor types. These data suggest that EMT may be a general biological switch rendering non-small cell lung tumors sensitive or insensitive to EGFR inhibition.  相似文献   
999.
Overexpression of CD24 has a negative impact on breast cancer prognosis. We have recently reported that the CD24 codon 57 Val/Val genotype (rs52812045) is associated with pathologic complete response after neoadjuvant chemotherapy for primary breast cancer and correlates with intratumoral lymphocyte infiltrates. This study was performed to investigate the influence of CD24 polymorphisms on breast cancer prognosis and risk. A total of 2,514 patients and 4,858 controls recruited as part of the MARIE study, a population-based case–control study, were genotyped for two CD24 polymorphisms (rs52812045, rs3838646) using TaqMan custom genotyping assays. Associations with overall and breast cancer-specific survival were assessed using uni- and multivariable Cox regression models stratified by age at diagnosis and adjusted for prognostic factors. Conditional logistic regression analysis adjusted for major risk factors was used to estimate multivariable odds ratios for risk of putative allele carriers compared to wildtype carriers. CD24 Ala/Val was significantly associated with breast cancer prognosis [Val/Val hazard ratio (HR)adjusted = 1.52; 95 % confidence interval (CI): 1.00–2.30, p = 0.05 and HRadjusted = 1.83; 95 % CI: 1.10–3.05, p = 0.018 for all-cause and breast cancer-specific mortality, respectively). The association was significant only in patients with a BMI <25 and in those who received adjuvant chemotherapy. None of the CD24 alleles was associated with breast cancer risk. These results provide further evidence of the CD24 Val/Val genotype influencing outcome in primary breast cancer. Together with previous data of CD24 overexpression as a poor prognostic marker, the findings underline the biological importance of CD24 for breast cancer.  相似文献   
1000.
Pericardial effusion in women with breast cancer   总被引:3,自引:0,他引:3  
Ninety patients with a history of breast cancer and pericardial effusion detected on echocardiography were identified and divided on a clinical basis into three groups. Group 1 consisted of 20 patients who had progressive metastatic breast cancer and echocardiography performed on a routine basis as a part of a clinical trial involving 38 patients. All 20 had small unexpected effusions, and only one patient developed symptomatic malignant pericardial disease late in her clinical course. Group 2 consisted of 32 patients who were without evidence of metastatic disease at the time of positive echocardiography and the etiology was considered benign in all patients. Six patients required pericardiectomy, five for severe radiation induced pericarditis and one for amyloid. No patient developed proven or suspected malignant pericardial disease. Group 3 comprised 38 patients who had known metastatic disease outside the pericardium at the time of positive echocardiography. Nineteen patients in Group 3 had histologically proven malignant involvement during life or at autopsy, and five more had suspected malignant pericardial disease. Ten patients initially were treated with pericardiectomy and 28 patients were managed with systemic therapy alone (24 patients) or with pericardiocentesis (four patients). Among the 12 patients with malignant effusion treated without surgery, proven local progression of pericardial disease occurred in six, with sudden death in two of those patients. No patient treated initially with surgery suffered progression of her pericardial disease. It was concluded that: small, clinically unsuspected pericardial effusions appear to be relatively common in women with metastatic breast cancer; no patient with clinical pericardial disease confirmed on echocardiography and no evidence of metastatic breast cancer developed malignant pericardial involvement; 50% of patients with known metastatic disease and a clinically apparent pericardial effusion had malignant pericardial disease; and nonsurgical therapy in patients with histologically proven or clinically suspected malignant pericardial effusion was associated with a high incidence of progressive pericardial disease.  相似文献   
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