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31.
PURPOSE: Radiolabeled annexin V may allow for repetitive and selective in vivo identification of apoptotic cell death without the need for invasive biopsy. This study reports on the relationship between quantitative technetium-99m- (99mTc-) 6-hydrazinonicotinic (HYNIC) radiolabeled annexin V tumor uptake, and the number of tumor apoptotic cells derived from histologic analysis. PATIENTS AND METHODS: Twenty patients (18 men, two women) suspected of primary (n = 19) or recurrent (n = 1) head and neck carcinoma were included. All patients underwent a spiral computed tomography (CT) scan, 99mTc-HYNIC annexin V tomography, and subsequent surgical resection of the suspected primary or recurrent tumor. Quantitative 99mTc-HYNIC annexin V uptake in tumor lesions divided by the tumor volume, derived from CT, was related to the number of apoptotic cells per tumor high-power field derived from terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end-labeling (TUNEL) assays performed on sectioned tumor slices. RESULTS: Diagnosis was primary head and neck tumor in 18 patients, lymph node involvement of a cancer of unknown primary origin in one patient, and the absence of recurrence in one patient. Mean percentage absolute tumor uptake of the injected dose per cubic centimeter tumor volume derived from tomographic images was 0.0003% (standard deviation [SD], 0.0004%) at 1 hour postinjection (PI) and 0.0001% (SD, 0.0000%) at 5 to 6 hours PI (P =.012). Quantitative 99mTc-HYNIC annexin V tumor uptake correlated well with the number of apoptotic cells if only tumor samples with no or minimal amounts of necrosis were considered. CONCLUSION: In the absence of necrosis, absolute 99mTc-HYNIC annexin V tumor uptake values correlate well with the number of apoptotic cells derived from TUNEL assays.  相似文献   
32.
PURPOSE: The aim of this study was to investigate the hypothesis that, independent of other known prognostic factors, pessimistic head and neck (H&N) cancer patients have a greater risk of being dead 1 year after diagnosis than do optimistic patients. PATIENTS AND METHODS: A prospective observational study design was used with a cohort of H&N cancer patients diagnosed during the period from March 1, 1997, to August 31, 1998, at the Centre Hospitalier Universitaire, Clermont-Ferrand, France. Dispositional optimism (DO) was evaluated at baseline using a French version of the Life Orientation Test translated and validated for this study. One-year survival status was collected on all subjects. The analysis of the hypothesized association between DO and 1-year survival was performed using multiple logistic regression analysis, controlling for other sociodemographic and clinical variables. RESULTS: The sample size was 101 patients, representing all but one of those patients fitting the inclusion criteria who were diagnosed during the recruitment period. Of these, 51 were alive at 1 year after diagnosis, 45 were dead, and five were lost to follow-up. The multivariate analysis was performed on the data from the 96 subjects in whom 1-year survival status was known. Controlling for known predictors of H&N cancer survival, pessimistic subjects (odds ratio [OR], 1.12; 95% confidence interval [CI], 1.01 to 1.24) and those living alone (OR, 4.14; 95% CI, 1.21 to 14.17) were more likely than optimistic subjects and those living with others to be dead at 1 year. CONCLUSION: The results of this study of a cohort of French H&N cancer patients indicate that dispositional optimism predicts 1-year survival independent of other sociodemographic and clinical variables.  相似文献   
33.
In order to compare phylogenetic methods and to reconstruct the evolutionary history of the tubercle bacilli, a set of macro-array-based genotyping data of Mycobacterium tuberculosis clinical isolates (called spoligotyping for spacer oligonucleotide typing, which assays the variability of the Direct Repeat -DR- locus), was analyzed in four settings of the Caribbean region (Guadeloupe, Martinique, Cuba and Haiti). A set of 47 alleles, split into 26 shared and 21 unique alleles) representative of 321 individual M. tuberculosis clinical isolates from patients residing in the above regions was studied. The following methods (and software in brackets) were investigated: numerical taxonomy distance methods (TAXOTRON), maximum parsimony procedure (PAUP), median-joining networks (NETWORK), and nested clade analysis (GEODIS). Results using these methods were analyzed, compared and discussed. The latter method (GEODIS) was investigated in detail by introducing geographical data together with genetic variability results to detect a link between population structure and population history, and to test the null hypothesis of no association between geography and genotypes. Irrespective of the methods used, our findings demonstrate that a core structure of four families (or clades) of M. tuberculosis strains is highly prevalent within the islands studied, indirectly reflecting passed colonization history of these different settings. Specificity of M. tuberculosis genotypes in each of the islands is discussed in the light of their respective colonial and contemporary histories.  相似文献   
34.
Plant-derived polyphenols flavonoids are increasingly being recognized for their medicinal potential. These bioactive compounds derived from plants are gaining more interest in ameliorating adverse health risks because of their low toxicity and few side effects. Among them, therapeutic approaches demonstrated the efficacy of catechins, a major group of flavonoids, in reverting several aspects of Down syndrome, the most common genomic disorder that causes intellectual disability. Down syndrome is characterized by increased incidence of developing Alzheimer’s disease, obesity, and subsequent metabolic disorders. In this focused review, we examine the main effects of catechins on comorbidities linked with Down syndrome. We also provide evidence of catechin effects on DYRK1A, a dosage-sensitive gene encoding a protein kinase involved in brain defects and metabolic disease associated with Down syndrome.  相似文献   
35.
OBJECTIVES: To evaluate the level of information and informed consent for maternal serum screening (MSS) for Down syndrome (DS) in the second trimester of pregnancy and analyse the exercise of autonomy towards the test by the women concerned. METHODS: We studied the population of pregnant women attending obstetric consultations in two French hospitals over a 3-month period. The women were assigned to three groups according to MSS results for DS: women at high risk of having a child with DS (group 1), women at low risk (group 2) and women who did not undergo the test (group 3). A questionnaire was completed before the medical consultation, to assess the quality of consent before amniocentesis for the group at high risk and before the second-trimester ultrasound scan for the other two groups. RESULTS: We analysed 305 questionnaires for 89, 137 and 79 women belonging to groups 1, 2 and 3 respectively. In total, 123 women (40.3% [IC 95%, 35-46%]) were considered to be well informed; 33 (10%, [IC 95%, 8-12%]) had a high level of knowledge, but made choices not consistent with their stated attitude, and 149 (49.7% [IC 95%, 45-56%]) were considered uninformed. Logistic regression analysis showed that maternal consent depended on three independent components: The score attributed to the doctor for information about MSS (t = 4.216, p < 0.001).Whether the patient belonged to group 1 (t = -2.631, p < 0.009).Educational level (< high-school diploma, high-school diploma or at least two years of higher education after high school) (t = 2.324, p < 0.02). The rate of consent increased with educational level and was highest for the women in group 1 and for those whose doctor had a high information score. CONCLUSIONS: Our findings clearly show that women are provided with insufficient information concerning MSS screening for DS in the second trimester of pregnancy for real and valid consent to be obtained.  相似文献   
36.
BackgroundWomen are nearly twice as likely as men to suffer from major depressive disorder. Yet, there is a dearth of studies comparing the clinical outcomes of women and men with treatment-resistant depression (TRD) treated with similar augmentation strategies. We aimed to evaluate the effects of the augmentation strategies in women and men at the McGill University Health Center.MethodsWe reviewed health records of 76 patients (42 women, 34 men) with TRD, treated with augmentation strategies including antidepressants (AD) with mood stabilizers (AD+MS), antipsychotics (AD+AP), or in combination (AD+AP+MS). Clinical outcomes were determined by comparing changes on the 17-item Hamilton Depression Rating Scale (HAMD-17), Montgomery-Åsberg Depression Rating Scale (MADRS), Quick Inventory of Depressive Symptomatology (QIDS-C16), and Clinical Global Impression rating scale (CGI-S) at the beginning and after 3 months of an unchanged treatment. Changes in individual items of the HAMD-17 were also compared between the groups.ResultsWomen and men improved from beginning to 3 months on all scales (P < .001, η p2 ≥ 0.68). There was also a significant sex × time interaction for all scales (P < .05, η p2 ≥ 0.06), reflecting a greater improvement in women compared with men. Specifically, women exhibited greater improvement in early (P = .03, η p2 = 0.08) and middle-of-the-night insomnia (P = .01, η p2 = 0.09) as well as psychomotor retardation (P < .001 η p2 = 0.16) and psychic (P = .02, η p2 = 0.07) and somatic anxiety (P = .01, η p2 = 0.10).ConclusionsThe combination of AD+AP/MS generates a significantly greater clinical response in women compared with men with TRD, supporting the existence of distinct pharmacological profiles between sexes in our sample. Moreover, they emphasize the benefit of augmentation strategies in women, underscoring the benefit of addressing symptoms such as insomnia and anxiety with AP and MS.  相似文献   
37.
38.
Aneurysms of the Internal Iliac Artery: Management Strategy   总被引:5,自引:0,他引:5  
With the widespread use of CT scans, detection and treatment of internal iliac artery aneurysms (IIA) have become more frequent. In the last few years, endovascular repair has been added to the therapeutic arsenal. We reviewed the records of 38 patients treated for 44 IIA between 1987 and 1997 to assess immediate and long-term outcome using various therapeutic methods. Aneurysms were divided into three groups according to the circumstances of treatment. Group I included 25 IIA treated at the same time as abdominal aortic aneurysm (AAA). The morbidity/mortality rate in this group was comparable to that in patients who underwent isolated AAA repair. Group II included 14 IIA treated during follow-up of AAA repair. Most complications in this group were intraoperative. Group III included five isolated IIA not associated with AAA repair. Complications were similar to those in group I. On the basis of this retrospective analysis, we propose a management strategy in which open surgery, endovascular repair, or both are used, depending on the circumstances of treatment.  相似文献   
39.
With the multiplication of electronic devices in our daily life, there is a need for tailored wideband electromagnetic (EM) absorbers that could be conformed on any type of surface-like antennas for interference attenuation or military vehicles for stealth applications. In this study, a wideband flexible flat electromagnetic absorber compatible with additive manufacturing has been studied in the X-Ku frequency bands. A multilayer structure has been optimized using a genetic algorithm (GA), adapting the restrictions of additive manufacturing and exploiting the EM properties of loaded and non-loaded filaments, of which the elaboration is described. After optimization, a bi-material multilayer absorber with a thickness of 4.1 mm has been designed to provide a reflectivity below −12 dB between 8 and 18 GHz. Finally, the designed multilayer structure was 3D-printed and measured in an anechoic chamber, achieving −11.8 dB between 7 and 18 GHz. Thus, the development of dedicated materials has demonstrated the strong potential of additive technologies for the manufacturing of thin wideband flexible EM absorbers.  相似文献   
40.
We report the case of a young female with embolic myocardial infarction. The embolic etiology was confirmed by Fourier Domain Optical Coherence Tomography as well as histo-pathology.  相似文献   
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