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81.
We examined tracking of ultrasound measurements of vascular structure and function in adulthood using data collected in the 2001 and 2007 follow-ups of Cardiovascular Risk in Young Finns Study. B-mode ultrasound measures of carotid artery intima-media thickness (IMT), carotid artery distensibility (CDist) and brachial artery flow-mediated dilatation (FMD) was obtained on 1809 apparently healthy Finnish adults aged 24 to 39 years in 2001 (1014 females; 795 males). Significant 6-year tracking was observed for IMT (males, r = 0.56; females, r = 0.46), CDist (males, r = 0.35; females, r = 0.36) and FMD (males, r = 0.23; females, r = 0.20). Subjects with 10-year risk of CVD (according to the SCORE risk score) above sex-specific median had improved IMT (r = 0.44; r = 0.57, p = 0.0001) and CDist (r = 0.31; r = 0.40, p = 0.03) tracking compared with those below median. Body mass index (BMI) ≥ 30 kg/m2 decreased tracking of CDist (r = 0.36; r = 0.19, p = 0.01). In conclusion, ultrasound measurements tracked low to moderate over 6-years and was influenced by cardiovascular disease (CVD) risk factor status. (E-mail: juho.raiko@utu.fi)  相似文献   
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Background  Clinical diagnosis of acute bacterial sinusitis (ABS) is a concern when a patient presents with nasal discharge of recent onset together with facial pain or pressure. Given this presentation, the doctor would benefit from having access to software that specifies, first, what diagnostic indicators experts typically use in that diagnosis and then, upon entry of those facts, what experts' typical probability of ABS is in such a case.
Methods  We specified a set of 23 hypothetical presentations of this type by patients 20–75 years of age, involving a comprehensive set of clinical-diagnostic indicators. Members of an international expert panel independently set the probability of ABS in each of these cases. A logistic function of the diagnostic indicators was fitted to the medians of the probabilities.
Results  The fitting led to an expression of the experts' median probability of ABS as a joint function of the duration of the patient's facial pain/pressure, and indicators of the location(s) of this; indicators of exacerbation of the pain/pressure on bending forward, nasal obstruction, maxillary and/or frontal tenderness, pus from middle meatus, purulent postnasal drip, and fever; and indicators of recent upper respiratory tract infection, nasal polyposis and status post sinus surgery. This probability function is accessible at http://www.evimed.ch/ABS .
Interpretation  That probability function, made readily accessible, provides for expertly probability setting in clinical diagnosis of ABS, relevant for decisions about further diagnostics or treatment without further tests.  相似文献   
84.
Members of the mammalian protein kinase C (PKC) superfamily play key regulatory roles in multiple cellular processes. In the heart, PKC signaling is involved in hypertrophic agonist-induced gene expression and hypertrophic growth. To investigate the specific function of PKC signaling in regulating cardiomyocyte growth, we used antisense oligonucleotides to inhibit PKC alpha, the major isozyme present in the neonatal heart. Transfection of cultured neonatal cardiomyocytes with antisense PKCalpha oligonucleotides resulted in a marked reduction in both PKCalpha mRNA and protein levels. PKCalpha antisense treatment also reduced phenylephrine (PE)-induced PKC activity and perinuclear translocation of PKCalpha. Antisense inhibition of PKCalpha led to reduction of PE-induced increase in skeletal alpha-actin mRNA levels and atrial natriuretic peptide (ANP) secretion but had no significant effects on PE-induced beta-myosin heavy chain, ANP, or B-type natriuretic peptide (BNP) gene expression. On the other hand, antisense PKCalpha treatment attenuated endothelin-1-induced increase in ANP and BNP peptide secretion, whereas endothelin-1-induced gene expression of ANP and BNP remained unchanged. The hypertrophic agonist-induced growth of cardiomyocytes, characterized by increased [(3)H]leucine incorporation, was not affected with antisense PKCalpha treatment. Furthermore, we found that PE-induced increase in extracellular signal-regulated kinase (ERK) activity was partially inhibited by antisense PKCalpha treatment, implicating ERK as a downstream mediator for PKCalpha signaling. These results indicate that PKCalpha isozyme is involved in hypertrophic signaling in cardiomyocytes and provide novel strategies for future studies to identify other cellular targets controlled selectively by PKCalpha or other PKC isozymes.  相似文献   
85.
Timing of onset of autoimmunity is a prerequisite for unmasking triggers and pathogenesis of type 1 diabetes. We followed 4,590 consecutive newborns with 8 or 3% HLA-DQB1 conferred risk for type 1 diabetes at 3-, 6-, or 12-month intervals up to 5.5 years of age. Islet cell autoantibodies (ICAs) and, in the 137 children with ICAs, insulin autoantibodies (IAAs), GAD65 autoantibodies (GADAs), and IA-2 protein autoantibodies (IA-2As) were measured. Children with high genetic risk developed ICAs more often than those with moderate risk (log-rank P = 0.0015); 85 and 91% remained ICA negative by 5 years of age, respectively. The time of appearance of biochemical autoantibodies was then compared with the appearance of ICAs. IAAs and GADAs emerged usually before ICAs (means -1.8 and -1.5 months, respectively) and IA-2As after ICAs (mean 2.0 months). Ninety-five percent of all IAAs, GADAs, and IA-2As seroconversions occurred in a cluster (-12 to 8 months) around the ICA seroconversion. We conclude that diabetes-associated autoantibodies emerged in children with predisposing HLA-DQB1 alleles after 3 months of age at a constant tempo, determined by the genetic risk level, usually in the order of IAA, GADA, ICA, and IA-2A. Seroconversion to multiple autoantibody positivity usually occurred tightly clustered in time.  相似文献   
86.
In order to develop the diagnosis of hemi-inattention in patients with right hemispheric cerebrovascular accident (RCVA), the initial starting point of cancellation performance was studied in seven commonly used visual cancellation tasks, an Object Finding task, and a blindfold Tactuo-motor search task. The subject groups consisted of 34 patients with RCVA and 31 healthy subjects. Patients were divided into groups of contralateral neglect and no neglect. One additional case of ipsilesional neglect and one of nonlateralised attentional disorder in relation to early orienting bias, are reported. Patients with contralateral neglect showed a strong tendency to start their cancellation performance on the right. Also, half of the nonneglect patient group demonstrated right bias in initiating their cancellation performance, suggesting the presence of a subclinical hemi-inattention group. Contrary to expectations, also a small proportion of normal subjects were right-biased. Task dependent differences in the assessment of early rightward orienting bias were found.  相似文献   
87.
Catechol-O-methyltransferase (COMT) catalyses the O-methylation of compounds having a catechol structure and its main function involves the elimination of biologically active or toxic catechols and their metabolites. By means of homologous recombination in embryonic stem cells, a strain of mice has been produced in which the gene encoding the COMT enzyme is disrupted. We report here the levels of catecholamines and their metabolites in striatal extracellular fluid in these mice as well as in homogenates from different parts of the brain, under normal conditions and after acute levodopa administration. In immunoblotting studies, COMT-knockout mice had no COMT protein in brain or kidney tissues but the amounts of catecholamine synthesizing and other metabolizing enzyme proteins were normal. Under normal conditions, COMT deficiency does not appear to affect significantly brain dopamine and noradrenaline levels in spite of relevant changes in their metabolites. This finding is consistent with previous pharmacological studies with COMT inhibitors and confirms the pivotal role of synaptic reuptake processes and monoamine oxidase-dependent metabolism in terminating the actions of catecholamines at nerve terminals. In contrast, when COMT-deficient mice are challenged with l-dihydroxyphenylalanine, they show an extensive accumulation of 3,4-dihydroxyphenylacetic acid and dihydroxyphenylglycol and even dopamine, revealing an important role for COMT under such situations. Notably, in some cases these changes appear to be Comt gene dosage-dependent, brain-region specific and sexually dimorphic. Our results may have implications for improving the treatment of Parkinson's disease and for understanding the contribution of the natural variation in COMT activity to psychiatric phenotypes.  相似文献   
88.
Human malignant mesothelioma (MM) is a highly aggressive neoplasm related to occupational asbestos exposure and characterised by a long latency period between the exposure and onset of disease. Previous studies indicate that losses at different genomic regions are present in MM. We examined allele loss at three known tumour suppressor gene regions (22q/NF2 gene, 9p/p16 gene, and 3p/FHIT gene) and at two other frequently deleted areas (14q and 6q) in MM. Loss of heterozygosity (LOH) was investigated in cell cultures and primary tumours with several highly polymorphic markers for each site. To study if LOH of the NF2 gene is a consistent feature in MM, we performed a more detailed analysis of chromosome 22q that included a NF2 marker (NF2CA3). We observed a high frequency of LOH occurring simultaneously at multiple loci. In particular, 100% of the cultured MM cells exhibited LOH at the NF2 gene region. From the other chromosomal sites analysed, recurrent allele loss was detected at 9p (5/7; 71%), 3p (4/7; 57%), 14q (3/7; 43%), and 6q (3/7; 43%). Of the 32 tumours, even those trimmed to exclude normal tissue, few showed LOH, suggesting consielment by normal cells within MM tumours, whereas tumour cells in primary cultures showed LOH already in passages 1-2. In conclusion, our present LOH data indicate that MM cells exhibit allele losses at multiple tumour suppressor gene sites concurrently, involving NF2 gene preferentially. This supports the view that the accumulation of multiple genetic hits is characteristic to malignant transformation of MM cells.  相似文献   
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90.
NKX3.1 is a prostate-specific homeobox gene located on chromosome 8p21. In the mouse, Nkx3.1 has growth-suppressive and differentiating effects on prostatic epithelium. Mutations of the coding region of NKX3.1 were not found in human prostate cancer, failing to support the notion that NKX3.1 was a tumor suppressor gene. To study the expression o NKX3.1 protein in human tissues and prostate cancer, we derived a rabbit antiserum against purified recombinant NKX3.1. Among normal human tissues, NKX3.1 expression was seen in testis, in rare pulmonary mucous glands, and in isolated regions of transitional epithelium of the ureter. NKX3.1 was uniformly expressed in nuclei of normal prostate epithelial cells in 61 histological sections from radical prostatectomy specimens. We analyzed 507 samples of neoplastic prostate epithelium, most of which were contained on a tissue microarray that contained samples from different stages of prostatic neoplasia. We observed complete loss of NKX3.1 expression in 5% of benign prostatic hyperplasias, 20% of high-grade prostatic intraepithelial neoplasias, 6% of T1a/b samples, 22% of T3/4 samples, 34% of hormone-refractory prostate cancers, and 78% of metastases. Our data show that NKX3.1 expression is highly, but not exclusively, specific for the prostate. Loss of NKX3.1 expression is strongly associated with hormone-refractory disease and advanced tumor stage in prostate cancer (P < 0.0001).  相似文献   
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