770 resultados para Dunn, Jack
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Lymphedema is an accumulation of lymph fluid in the limb resulting from an insufficiency of the lymphatic system. It is commonly associated with surgical or radiotherapy treatment for breast cancer. As with many progressively debilitating disorders, the effectiveness of treatment is significantly improved by earlier intervention. Multiple frequency bioelectrical impedance analysis (MFBIA) previously was shown to provide accurate relative measures of lymphedema in the upper limb in patients after treatment for breast cancer, This presentation reports progress to date on a three-year prospective study to evaluate the efficacy of MFBIA to predict the early onset of lymphedema in breast cancer patients following treatment. Bioelectrical impedance measurements of each upper limb were recorded in a group of healthy control subjects (n = 50) to determine the ratio of extracellular limb-fluid volumes. From this population, the expected normal range of asymmetry (99.7% confidence) between the limbs was determined, Patients undergoing surgery to treat breast cancer were recruited into the study, and MFBIA measurements were recorded presurgery, at one month and three months after surgery, and then at two-month intervals for up to 24 months postsurgery, When patients had an MFBIA measure outside the 99.7% range of the control group, they were referred to their physician for clinical assessment. Results to date: Over 100 patients were recruited into the study over the past two years; at present, 19 have developed lymphedema and, of these, 12 are receiving treatment. In each of these 19 cases, MFBIA predicted the onset of the condition up to four months before it could be clinically diagnosed. The false-negative rate currently is zero, The study will continue to monitor patients over the remaining year to accurately ascertain estimates of specificity and sensitivity of the procedure.
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Neonate Lepidoptera are confronted with the daunting task of establishing themselves on a food plant. The factors relevant to this process need to be considered at spatial and temporal scales relevant to the larva and not the investigator. Neonates have to cope with an array of plant surface characters as well as internal characters once the integument is ruptured. These characters, as well as microclimatic conditions, vary within and between plant modules and interact with larval feeding requirements, strongly affecting movement behavior, which may be extensive even for such small organisms. In addition to these factors, there is an array of predators, pathogens, and parasitoids with which first instars must contend. Not surprisingly, mortality in neonates is high but can vary widely. Experimental and manipulative studies, as well as detailed observations of the animal, are vital if the subtle interaction of factors responsible for this high and variable mortality are to be understood. These studies are essential for an understanding of theories linking female oviposition behavior with larval survival, plant defense theory, and population dynamics, as well as modern crop resistance breeding programs.
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Following the Ninth International Congress of Toxicology (ICT-IX) and its satellite meeting ‘The International Conference on the Environmental Toxicology of Metals and Metalloids’ held in 2001 in Australia, a special issue on Arsenic was published in July 2002 (Toxicology Letters, 133(1), 1–120, 2002). We felt that it was timely to follow up with a special issue covering a wider range of metals and metalloids. Participants from the above conferences were invited to contribute to this special issue on ‘Environmental Toxicology of Metals and Metalloids’. This special issue consists of 11 manuscripts, representing up to date studies on a number of important harmful elements including aluminium, arsenic, cadmium, selenium, tin (tributyltin) and zinc. It illustrates the multidisciplinary nature of modern research in environmental toxicology involving chemical, biological and molecular technological approaches. It has been our great pleasure to produce this special issue. We would like to thank the authors for their contributions. We greatly appreciate the guidance and assistance provided by Dr J.P. Kehrer (Managing Editor), Dr Lulu Stader (Senior Publishing Editor) and their colleagues at Elsevier Science.
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Purpose: To evaluate wavefront performance and modulation transfer function (MTF) in the human eye aft er the implantation of diffractive or refractive multifocal intraocular lenses (IOLs). Materials and Methods: This was a prospective, interventional, comparative, nonrandomized clinical study. Uncorrected distance and near visual acuity, and wavefront analysis including MTF curves (iTrace aberrometer, Tracey Technologies, Houston, TX, USA) were measured in 60 patients aft er bilateral IOL implantation with 6 months of follow-up. Forty eyes received the diffractive ReSTOR (Alcon), 40 eyes received the refractive ReZoom (Advanced Medical Optics) and 40 eyes, the Tecnis ZM900 (Advanced Medical Optics). The comparison of MTF and aberration between the intraocular lenses was performed using analysis of variance (ANOVA), followed by the Dunn test when necessary. Results: The mean uncorrected distance visual acuity was similar in all three groups of multifocal IOLs. The ReSTOR group provided better uncorrected near visual acuity than the ReZoom group (P < 0.001), but similar to the Tecnis group. Spherical aberration was significantly higher in the ReZoom group (P = 0.007). Similar MTF curves were found for the aspheric multifocal IOL Tecnis and the spheric multifocal IOL ReSTOR, and both performed better than the multifocal IOL ReZoom in a 5 mm pupil (P < 0.001 at all spatial frequencies). Conclusions: Diffractive IOLs studied presented similar MTF curves for a 5 mm pupil diameter. Both diffractive IOLs showed similar spherical aberration, which was significantly better with the full-diffractive IOL Tecnis than with the refractive IOL ReZoom.
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A line of FVB (H-2(q)) mice transgenic for the E6/E7 open reading frames of Human Papillomavirus type 16 driven from the alpha-A crystallin promoter expresses E7 mRNA in lens and skin epithelium. E7 protein is detectable in adult skin, coinciding with the development or inflammatory skin disease, which progresses to papillomata and squamous carcinomata in some mice. By examining the outcome of parenteral immunization with E7 protein, we sought to determine whether endogenous expression of E7 in skin had induced a preexisting immune outcome, i.e., specific immunity or tolerance, or whether the mice remain naive (''ignorant'') to E7. Our data show that the antibody response to defined E7 B-epitopes, the proliferative response to Th epitopes, and the delayed-type hypersensitivity (DTH) response to whole E7 did not differ between groups or young and old E6/E7 transgenic mice (likely having different degrees of lifetime exposure to E7 protein) or between E6/E7-transgenic and nontransgenic parental strain control mice. Although an E7-specific CTL response could not be induced in the H-2(q) background of these mice, incorporation of a D-b allele into the genome allowed comparison of D-b-restricted CTL responses in E6/E7 transgenic and nontransgenic mice. Experiments indicated that the E7-immunization-induced CTL response did not differ significantly between E6/E7 transgenic and nontransgenic mice. We interpret these results to indicate that in spite of expression of E7 protein in adult skin, E6/E7 transgenic mice remain immunologically naive (ignorant) of E7 epitopes presented by immunization. (C) 1997 Academic Press.
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Changes in molecular motion in blends of PEO-PVPh have been studied using measurements of C-13 T-1 rho relaxation times. C-13 T-1 rho relaxation has been confirmed as arising from spin-lattice interactions by observation of the variation in T-1 rho with rf field strength and temperature. In the pure homopolymers a minimum in T-1 rho is observed at ca. 50 K above the glass transition temperatures detected by DSC. After blending, the temperature of the minimum in T-1 rho for PEO increased, while that for PVPh decreased, however, the minima, which correspond to the temperatures where the average correlation times for reorientation are close to 3.1 mu s, are separated by 45 K (in a 45% PEO-PVPh blend). These phenomena are explained in terms of the local nature of T-1 rho measurements. The motions of the individual homopolymer chains are only partially coupled in the blend. A short T-1 rho has been observed for protonated aromatic carbons, and assigned to phenyl rings undergoing large-angle oscillatory motion, The effects of blending, and temperature, on the proportion of rings undergoing oscillatory motion are analyzed.
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The E7 transforming protein of Human Papillomavirus type 16 (HPV16) is expressed in the skin of a line of RIB mice transgenic for the E6 and E7 open reading frames of HPV16 driven from the alpha A crystallin promoter (FVB alpha AcryHPV16E6E7). We have transferred skin from FVB alpha AcryHPV16E6E7 mice to naive or E7-primed syngeneic NE recipients to assess whether the E7 protein of HPV16 can function as a minor transplantation antigen (MTA) and promote skin graft rejection. FVB mice did not reject E7 expressing tail or flank skin grafts. E7 immunized FVB x C57BL/6J mice recipients of FVB alpha AcryHPV16E6E7 x C57BL/6J skin generated humoral and DTH responses to E7 in vivo and E7-specific CTL precursors in the spleen, but failed to reject 57 expressing tail skin grafts by 100 days posttransfer. Thus although HPV16 E7 + ve mesenchymal and endodermal tumors can be eliminated by an E7-specific immune response, the same protein is unable to act as a MTA and promote graft rejection when expressed in skin cells. Lack of rejection of grafts expressing MTAs such as E7 may be relevant to the immunology of epithelial tumors expressing tumor-specific antigens and to our understanding of the immunology of diseases of the skin. (C) 1997 Academic Press.
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Primary or idiopathic osteoarthritis (OA) of the hip has increasingly been attributed to the presence of presumably minor femoral or acetabular deformities that are not routinely identified. The alpha angle reflects one such deformity of the femoral neck and reflects a risk for femoroacetabular impingement, which in turn reportedly is associated with OA. If impingement is in fact associated with OA, then one might expect the mean alpha angle to be greater in patients with presumed idiopathic hip OA. We therefore compared the alpha angle among a group of elderly patients with idiopathic OA with that in a control group of elderly individuals without OA. We measured the alpha angles in 50 individuals (72 hips) with a mean age of 70 years (range, 60-84 years) with apparently idiopathic OA and compared their angles with those from a control group of 56 individuals without OA. The alpha angle was measured by means of radiographs of their hips using the Dunn view at 45A degrees flexion. The patients with OA had a greater percentage with abnormal alpha angles than did the normal subjects: 82% versus 30%, respectively. The mean alpha angle in the group with OA was larger than in the control subjects: 66.4A(0) (range, 28A degrees-108A degrees) versus 48.1A(0) (range, 34A degrees-68A degrees). Hips with presumably idiopathic OA had more abnormalities at the femoral head-neck junction than did the control hips without OA and may relate to the risk of OA developing. Level II, prognostic study. See Guidelines for Authors for a complete description of levels of evidence.
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Background/Aims: Hepatocellular carcinoma (HCC) is a well recognized complication of advanced NASH (non-alcoholic steatohepatitis). We sought to produce a rat model of NASH, cirrhosis and HCC. Methods: Adult Sprague-Dawley rats, weighing 250-300 g, were fed a choline-deficient, high trans-fat diet and exposed to DEN in drinking water. After 16 weeks, the animals underwent liver ultrasound (US), sacrifice and assessment by microscopy, immunohistochemistry and transmission electron microscopy (TEM). Results: US revealed steatosis and focal lesions in 6 of 7. All had steatohepatitis defined as inflammation, advanced fibrosis and ballooning with Mallory-Denk bodies (MDB) with frank cirrhosis in 6. Areas of more severe injury were associated with anti-CK19 positive ductular reaction. HCC, present in all, were macro-trabecullar or solid with polyhedral cells with foci of steatosis and ballooned cells. CK19 was positive in single or solid nests of oval cells and in neoplastic hepatocytes. TEM showed ballooning with small droplet fat, dilated endoplasmic reticulum and MDB in non-neoplastic hepatocytes and small droplet steatosis in some cancer cells. Conclusions: This model replicated many features of NASH including steatohepatitis with ballooning, fibrosis, cirrhosis and hepatocellular carcinoma. Oval cell proliferation was evident and the presence anti-CK 19 positivity in the cancer suggests oval cell origin of the malignancy. (C) 2008 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.
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The amygdala participates in the detection and control of affective states, and has been proposed to be a site of dysfunction in affective disorders. To assess amygdala processing in individuals with unipolar depression, we applied a functional MRI (fMRI) paradigm previously shown to be sensitive to amygdala function. Fourteen individuals with untreated DSM-IV major depression and 15 healthy subjects were studied using fMRI with a standardized emotion face recognition task. Voxel-level data sets were subjected to a multiple-regression analysis, and functionally defined regions of interest (ROI), including bilateral amygdala, were analyzed with MANOVA. Pearson correlation coefficients between amygdala activation and HAM-D score also were performed. While both depressed and healthy groups showed increased amygdala activity when viewing emotive faces compared to geometric shapes, patients with unipolar depression showed relatively more activity than healthy subjects, particularly on the left. Positive Pearson correlations between amygdala activation and HAM-D score were found for both left and right ROIs in the patient group. This study provides in vivo imaging evidence to support the hypothesis of abnormal amygdala functioning in depressed individuals. (C) 2009 Elsevier Ireland Ltd. All rights reserved.
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We aimed to quantify fatigue frequency and evolution in amyotrophic lateral sclerosis (ALS), and to correlate fatigue with factors such as age, sex, educational level, disease duration, functionality, quality of life, dyspnoea, depression and sleepiness. Sixty ALS patients (test group: TG) selected by El Escorial criteria and 60 normal individuals (control group: CG) matched according to sex and age, were followed every three months, during 9 months, by means of self-report scales: Fatigue Assessment Instrument (Fatigue Severity Scale plus three qualitative subscales); ALS Functional Rating Scale; McGill Quality of Life Questionnaire; dyspnoea analogical scale; Beck Depression Inventory and Epworth Sleepiness Scale. Fatigue was reported by 83% of TG (median: 3.6, interquartile range 1.5-5.4), compared with 20% of CG (median: 1, 1 - 1), and was significantly greater in the TG (p < 0.001, Mann-Whitney test). Fatigue severity increased by the ninth month of the study (p=0.0008, Friedman, Muller-Dunn post test). There was no correlation between fatigue and other parameters, except for an inverse correlation with age at disease onset (p=0.0395, Spearman rank correlation). In conclusion, fatigue was frequent in ALS, greater in the youngest patients and worsened during follow-up. Possibly, ALS related fatigue is an independent factor, which deserves individualized approach and treatment.
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Transcripts that lack any protein-coding potential represent at least half of the identified elements transcriptome. We review the evidence for the existence of such transcripts in the mammalian transcriptome, and argue that there may be many more noncoding RNAs (ncRNAs) still to be discovered. Relatively few ncRNA “genes” have been ascribed a function based upon mutation analysis. The review discusses possible roles of ncRNAs as cis-acting and trans-acting elements in epigenetic transcriptional control, including monoallelic gene silencing and imprinting. We also consider the evidence that the production of ncRNAs is a common feature of transcriptional enhancers.