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141.
Guy RJ Breschkin AM Keenan CM Catton MG Enriquez AM Hellard ME 《Journal of acquired immune deficiency syndromes (1999)》2005,38(4):495-499
Between 1999 and 2000, new diagnoses of HIV in Victoria (Australia) rose by 41%, from 140 to 197. In this time period, sera from new HIV diagnoses were tested using the Organon Teknika "detuned" enzyme immunoassay (EIA). We compared the results of the detuned EIA with incident infections defined by surveillance (on the basis of a previous negative or indeterminate HIV test and/or a seroconversion illness within the 12 months preceding HIV diagnosis). Of 317 specimens, 97 (31%) incident infections and 114 (36%) recent infections were detected using surveillance and detuned EIA, respectively. The detuned assay misclassified 11 cases with AIDS and 2 cases with CD4 counts < or = 200 micro3 (probable long-standing infections) as recent infections and was unable to identify 31 (32%) of 97 cases previously classified as incident cases by surveillance. The assay detected an extra 35 recent infections that were previously classified as nonincident by surveillance. By combining the detuned assay and surveillance, 132 (42%) incident infections were identified from 317 specimens, 36% more than surveillance alone. We recommend that a detuned assay or similar test become part of the routine strategy to identify incident infections in Victoria. Incident infections provide important information for targeting prevention strategies and the opportunity to interrupt ongoing viral transmission. 相似文献
142.
Chaiken J Finney W Knudson PE Weinstock RS Khan M Bussjager RJ Hagrman D Hagrman P Zhao Y Peterson CM Peterson K 《Journal of biomedical optics》2005,10(3):031111
Tissue modulated Raman spectroscopy was used noninvasively to measure blood glucose concentration in people with type I and type II diabetes with HemoCue fingerstick measurements being used as reference. Including all of the 49 measurements, a Clarke error grid analysis of the noninvasive measurements showed that 72% were A range, i.e., clinically accurate, 20% were B range, i.e., clinically benign, with the remaining 8% of measurements being essentially erroneous, i.e., C, D, or E range. Rejection of 11 outliers gave a correlation coefficient of 0.80, a standard deviation of 22 mg/dL with p<0.0001 for N=38 and places all but one of the measurements in the A and B ranges. The distribution of deviations of the noninvasive glucose measurements from the fingerstick glucose measurements is consistent with the suggestion that there are at least two systematic components in addition to the random noise associated with shot noise, charge coupled device spiking, and human factors. One component is consistent with the known variation of fingerstick glucose concentration measurements from laboratory reference measurements made using plasma or whole blood. A weak but significant correlation between the deviations of noninvasive measurements from fingerstick glucose measurements and the test subject's hemoglobin concentration was also observed. 相似文献
143.
Combined reflectance and fluorescence spectroscopy for in vivo detection of cervical pre-cancer 总被引:1,自引:0,他引:1
Chang SK Mirabal YN Atkinson EN Cox D Malpica A Follen M Richards-Kortum R 《Journal of biomedical optics》2005,10(2):024031
Optical technologies, such as reflectance and fluorescence spectroscopy, have shown the potential to provide improved point-of-care detection methods for cervical neoplasia that are sensitive, specific, and cost-effective. Our specific goals are to analyze the diagnostic potential of reflectance and fluorescence spectra, alone and in combination, to discriminate normal and precancerous cervical tissue in vivo and to identify which classification features contain significant diagnostic information. Reflectance spectra are measured at four source-detector separations and fluorescence emission spectra are measured at 16 excitation wavelengths, from 324 sites in 161 patients. These 20 spectral features are permuted in all possible combinations of one, two, and three; and classification algorithms are developed to evaluate the diagnostic performance of each combination. Algorithms based on fluorescence spectra alone yield better diagnostic performance than those based on reflectance spectra alone. The combination of fluorescence and reflectance do not significantly improve diagnostic performance compared to fluorescence alone, except in the case of discriminating high-grade precancers from columnar normal tissue. In general, fluorescence emission spectra at 330- to 360-nm and 460- to 470-nm excitation provide the best diagnostic performance for separating all pairs of tissue categories. 相似文献
144.
145.
Objective and Design: Whilst the anti-microbial properties of tea tree oil (TTO) are established, the anti-inflammatory effects of TTO in human skin remain largely anecdotal and require evaluation. This study examined the effect of topically applied TTO on nickel-induced contact hypersensitivity reactions in human dorsal skin.Treatment: TTO (100%), a 5% TTO lotion, a placebo lotion (no TTO), or 100% macadamia oil were applied at days 3 and 5 after nickel exposure.Methods: The flare area and erythema index were measured on days 3, 5 and 7. The regulatory effects of TTO were also investigated on the proliferative response to nickel or polyclonal mitogens by peripheral blood mononuclear cells from nickel-sensitive and control subjects.Results: TTO (100%) significantly reduced the flare area and erythema index when compared to the nickel-only sites. With respect to the erythema index, the anti-inflammatory effects were predominantly, but not exclusively, seen in a subgroup of nickel-sensitive subjects with a prolonged development phase of nickel-induced contact hypersensitivity response. The 5% TTO lotion, the placebo lotion and the 100% macadamia oil were all without significant effect. TTO significantly inhibited proliferation to nickel but not to non-specific polyclonal mitogens by peripheral blood mononuclear cells from nickel-sensitive subjects.Conclusions: Topical application of 100% TTO may have therapeutic benefit in nickel-induced contact hypersensitivity in human skin. The mode of action of TTO requires further investigation, but may be an effect on the antigen presenting cells or the antigen presenting process in nickel-induced contact hypersensitivity, as well as vascular changes associated with this response.Received 14 February 2004; returned for revision 30 June 2004; accepted by J. S. Skotnicki 13 September 2004 相似文献
146.
Isolation and characterization of Mycoplasma sphenisci sp. nov. from the choana of an aquarium-reared jackass penguin (Spheniscus demersus) 下载免费PDF全文
Frasca S Weber ES Urquhart H Liao X Gladd M Cecchini K Hudson P May M Gast RJ Gorton TS Geary SJ 《Journal of clinical microbiology》2005,43(6):2976-2979
Strain UCMJ was isolated from the choana of a jackass penguin (Spheniscus demersus) with recurrent mucocaseous choanal discharge. Isolation of this mycoplasma expands the known range of species hosting mycoplasmas. The name Mycoplasma sphenisci sp. nov. is proposed for this new species, for which strain UCMJ is the type strain. 相似文献
147.
148.
Identification of cathepsin C mutations in ethnically diverse papillon-Lefèvre syndrome patients 下载免费PDF全文
Hart PS Zhang Y Firatli E Uygur C Lotfazar M Michalec MD Marks JJ Lu X Coates BJ Seow WK Marshall R Williams D Reed JB Wright JT Hart TC 《Journal of medical genetics》2000,37(12):927-932
INTRODUCTION—Papillon-Lefèvre syndrome (PLS) is an autosomal recessive disorder characterised by palmoplantar keratoderma and severe, early onset periodontitis, which results from deficiency of cathepsin C activity secondary to mutations in the cathepsin C gene. To date, 13 different cathepsin C mutations have been reported in PLS patients, all of which are homozygous for a given mutation, reflecting consanguinity.
AIM—To evaluate the generality of cathepsin C mutations in PLS, we studied an ethnically diverse group of 20 unrelated families.
METHODS—Mutations were identified by direct automated sequencing of genomic DNA amplified for exonic regions and associated splice site junctions of the cathepsin C gene. Long range PCR was performed to determine the genomic structure of the cathepsin C gene.
RESULTS—The cathepsin C gene spans over 46 kb, with six introns ranging in size from 1.6 to 22.4 kb. Eleven novel mutations and four previously reported mutations were identified in affected subjects from 14 families. Missense mutations were most common (9/15), followed by nonsense mutations (3/15), insertions (2/15), and deletions (1/15). Among these 14 probands, two were compound heterozygotes. Affected subjects with transgressions of the dermal lesions onto the knees or elbows or both had mutations in both the pro- and mature regions of the enzyme, although most were in the mature region.
CONCLUSION—Mutations in the mature region of cathepsin C were more likely to be associated with the transgressions of the dermatological lesions, although the results were not statistically significant. A comprehensive list of all cathepsin C mutations described to date, representing 25 mutations from 32 families with PLS and related conditions, is also presented.
Keywords: cathepsin C; genetics; severe early onset periodontitis; hyperkeratosis 相似文献
AIM—To evaluate the generality of cathepsin C mutations in PLS, we studied an ethnically diverse group of 20 unrelated families.
METHODS—Mutations were identified by direct automated sequencing of genomic DNA amplified for exonic regions and associated splice site junctions of the cathepsin C gene. Long range PCR was performed to determine the genomic structure of the cathepsin C gene.
RESULTS—The cathepsin C gene spans over 46 kb, with six introns ranging in size from 1.6 to 22.4 kb. Eleven novel mutations and four previously reported mutations were identified in affected subjects from 14 families. Missense mutations were most common (9/15), followed by nonsense mutations (3/15), insertions (2/15), and deletions (1/15). Among these 14 probands, two were compound heterozygotes. Affected subjects with transgressions of the dermal lesions onto the knees or elbows or both had mutations in both the pro- and mature regions of the enzyme, although most were in the mature region.
CONCLUSION—Mutations in the mature region of cathepsin C were more likely to be associated with the transgressions of the dermatological lesions, although the results were not statistically significant. A comprehensive list of all cathepsin C mutations described to date, representing 25 mutations from 32 families with PLS and related conditions, is also presented.
Keywords: cathepsin C; genetics; severe early onset periodontitis; hyperkeratosis 相似文献
149.
Normal adolescent development is often accompanied by transient emotional and behavioral problems. For most individuals with postpubertal-onset adjustment problems, there is a resolution by early adulthood and relative stability through the adult life span. But for a minority, adjustment problems escalate during adolescence and portend the development of serious mental illness in adulthood. In this article, we explore adolescent behavioral changes and neurodevelopmental processes that might contribute to stress sensitivity and vulnerability for the emergence of the mental disorders. Of particular interest is the role that hormonal changes might play in the expression of genetic vulnerabilities for psychopathology. Drawing on recent findings from clinical research and behavioral neuroscience, we describe the ways in which postpubertal hormones might alter brain function and, thereby, behavior. It is concluded that there are both activational and organization effects of hormones on the adolescent brain, and these contribute to developmental discontinuities in behavioral adjustment. Implications for adult psychopathology and preventive intervention are discussed. 相似文献
150.
Mark S. Sothmann Thelma S. Horn Barbara A. Hart Anthony B. Gustafson 《Psychophysiology》1987,24(1):47-54
Discrete cardiovascular fitness groups consisting of high-fit (n=10) and low-fit (n=9) men performed a well-learned vigilance task and their self-report, performance, and plasma catecholamine responses were compared. No significant differences were observed between the fitness groups on self-report or psychomotor performance responses to the vigilance task. However, the low-fit group took significantly longer than high-fit subjects to complete the first of three sets of anagrams administered immediately after the vigilance task. Plasma norepinephrine but not epinephrine response was greater in the low-fit group compared to their high-fit counterparts. The findings indicate that enhanced cardiovascular fitness may be characterized by an attenuated plasma norepinephrine response to a vigilance task with sustained cognitive performance subsequent to the task. 相似文献