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Association of human polyomavirus JC with peripheral blood of immunoimpaired and healthy individuals
Drries Kristina Sbiera Silviu Drews Klaus Arendt Gabriele Eggers Christian Drries Rdiger 《Journal of neurovirology》2003,9(1):81-87
JC virus (JCV) infection is regularly asymptomatic in healthy individuals. In contrast, in immunocompromised individuals, highly activated virus replication may lead to PML. Peripheral blood cells (PBCs) are found to habor JCV DNA in healthy and diseased individuals and it is discussed that they might be responsible for dissemination of the virus to the central nervous system (CNS) during persistence. To better understand the role of JCV DNA in PBCs for persistent infection and pathogenesis, the authors characterized the extent of JCV infection in Ficoll-gradient purified blood cells (peripheral blood mononuclear cells [PBMCs]) of healthy and human immunodeficiency virus type 1 (HIV-1)-infected individuals. Virus activation in PBMCs from healthy JCV-infected individuals was found at a rate of 0% to 38% at low polymerase chain reaction (PCR) sensitivity. In progressive multifocal leukoencephalopathy (PML) patients, a stronger signal was found, indicating increased virus activation. JCV DNA was regularly detected in T and B lymphocytes and in monocytes at low levels. However, granulocytes were shown to be the predominant reservoir of JCV DNA harboring high copy numbers. Although the overall distribution of viral genomes holds true for the population studied, in the individual, a markedly changed pattern of distribution can be found. 相似文献
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T. A. Drews K. G. Lamping D. E. Laughlin W. P. Dole 《Medical & biological engineering & computing》1987,25(4):420-427
Although present sonomicrometer techniques for measuring continuous changes in vascular diameter are very useful, two problems
with available methods are difficulty in maintaining crystal alignment throughout an acute experiment and inability to measure
absolute dimensions less than 1 mm. We have designed and ultrasonic dimension gauge system to over come these problems. The
design uses a gate to pass a 20 MHz signal to a counter during the sonic travel time between crystals, and then converts the
digital count to an analogue voltage. Interference from the transmitting impulse in the received signal was minimised using
MOSFET transistors allowing measurements of absolute dimensions from 0.00 mm to 99.9 mm. An averaging effect which depends
upon the asynchrony between the basic timer and the counter clock results in a resolution of at least 10 μm. Repeated calibration
curves showed an accuracy of 2.5 μm without significant bias. Piezoelectric crystals were mounted to a lighweight stainless-steel
clip to facilitate attachment to the vessel and to maintain the crystals in focus during changes in diameter. Mean and phasic
diameters measured in the femoral artery with the clip device correlated well with measurements obtained with crystals sewn
to the adventitia of the femoral artery of the dog (slope =0.97, r=0.99). 相似文献
6.
OBJECTIVE: To examine parenting stress among caregivers of young children with congenital cataracts and to assess whether diagnostic and/or treatment differences are associated with differences in perceived parenting stress. METHODS: Parents of 41 preschool-age children with congenital cataracts (13 with bilateral cataracts [BCCs] and 28 with unilateral cataracts [UCCs], of whom 14 were aphakic and 14 were pseudophakic) completed the Parenting Stress Index (PSI) and/or a disease-specific parental stress measure, ie, the Ocular Treatment Index (OTI). RESULTS: The 28-item OTI had excellent internal consistency (alpha = 0.94) and supported three of four a priori validity hypotheses. Parents of children with congenital cataracts reported normal parenting stress levels on the PSI. Parents of children with UCCs tended to report higher levels of stress, but not significantly so, than did parents of children with BCCs. Among parents of children with UCCs, those whose children were aphakic reported higher levels of stress on the OTI and all of the PSI subscales than did parents of pseudophakic children. These differences were statistically significant for two subscales (Adaptability [P =.03] and Mood [P =.01]). CONCLUSIONS: Although parents of children with congenital cataracts generally did not report increased parenting stress levels, clinicians should be aware that parenting stress can adversely impact patients' families. We did observe higher stress levels in parents with children who had UCCs and did not receive an intraocular lens-particularly stress related to their child's reaction to sensory stimulation and mood-compared with parents of pseudophakic children. Thus, clinicians may want to consider parenting stress levels when choosing a treatment for children with UCCs, especially because such stress has been associated with poor treatment compliance for children with other chronic conditions. 相似文献
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Takeshi Komoda MD Thorsten Drews MD Hans B. Lehmkuhl MD Roland Hetzer MD PhD 《Journal of artificial organs》2006,9(1):29-33
The Eurotransplant (ET) allocation algorithm, newly implemented in 2000, gives priority for heart transplantation (HTx) to
patients with high urgency (HU) status, but now this status is rescinded upon ventricular assist device (VAD) implantation
and only regained if severe complications occur during mechanical circulatory support (MCS). We studied the effects of this
change on the patients in our institute who were waiting for HTx with MCS. The median duration of MCS until HTx in adult patients
gradually increased from 3.1 months in 1994, reaching a peak of 16.7 months in 2000, and then gradually decreased to 6.0 months
in 2003. Among the patients with VAD implantation as a bridge to HTx, two patients were on MCS for more than 1 year (the longest
duration of MCS being 1.6 years) at the end of 1999, and this figure increased to nine patients and a maximum MCS duration
of 3.7 years at the end of 2003. These data imply that the patients in whom a complication occurred in the early phase of
MCS and who had overcome this complication underwent HTx early with HU status, and those who were stable during MCS waited
a long time for HTx. Furthermore, the number of patients in the latter group is increasing. The new allocation algorithm imposes
on patients with MCS waiting for HTx who are relatively young and free from complications and serious coexisting disease,
very long-term MCS without an end to VAD bridging, which is almost equivalent to destination therapy.
Part of this paper was presented at the 42nd JSAO Conference (Tokyo, October 5–7, 2004) 相似文献
9.
Qualitatively different organizational structures of lexical knowledge in the left and right hemisphere 总被引:2,自引:0,他引:2
E Drews 《Neuropsychologia》1987,25(2):419-427
The present study investigates and discusses the organization of lexical knowledge in the intact left and right hemisphere within the framework of hemisphere-specific cognitive modes of processing. Using a divided visual field technique, word pairs of concrete nouns had to be judged. Semantic relation was either intraconceptual (coordinates) or interconceptual (locative). The results suggest that the left hemisphere, lexical structures are predominantly based on intraconceptual relationships corresponding to its analytic sequential processing mechanism, whereas in the right hemisphere, lexical entries are exclusively associated by means of interconceptual relationships in accordance with its "gestalthaft" holistic processor. 相似文献
10.
Iciek R Wender-Ozegowska E Seremak-Mrozikiewicz A Drews K Brazert J 《Ginekologia polska》2007,78(8):642-646
The article presents information about leptin as the major metabolic hormone. The structure, localization of the hormone and its receptor have been described focusing on maturation and fertility processes. Several polymorphisms of leptin gene and its receptor have been described as potential developmental factors of pregnancy complications such as diabetes mellitus or pregnancy induced hypertension. 相似文献