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21.
Vaughan JR; Farrer MJ; Wszolek ZK; Gasser T; Durr A; Agid Y; Bonifati V; DeMichele G; Volpe G; Lincoln S; Breteler M; Meco G; Brice A; Marsden CD; Hardy J; Wood NW 《Human molecular genetics》1998,7(4):751-753
A mutation in exon 4 of the human alpha-synuclein gene was reported
recently in four families with autosomal dominant Parkinson's disease (PD).
In order to examine whether mutations in this exon or elsewhere in the gene
are common in familial PD, all seven exons of the alpha- synuclein gene
were amplified by PCR from index cases of 30 European and American
Caucasian kindreds affected with autosomal dominant PD. Each product was
sequenced directly and examined for mutations in the open reading frame. No
mutations were found in any of the samples examined. We conclude that the
A53T change described in the alpha- synuclein gene is a rare cause of PD or
may even be a rare variant. Mutations in the regulatory or intronic regions
of the gene were not excluded by this study.
相似文献
22.
Effect of histamine infusion on circulating methionine-enkephalin and catecholamine concentrations 总被引:1,自引:0,他引:1
In 5 normal adult men, histamine was infused i.v. for 5 min at 20 micrograms/kg/h and at 80 micrograms/kg/h on two occasions one week apart. Diastolic blood pressure fell and heart rate, plasma adrenaline and noradrenaline all rose in a dose-dependent manner, but plasma methionine-enkephalin (Met-Enk) concentrations were unchanged. These results indicate that while Met-Enk may be co-stored with catecholamines (CAs) in the adrenal medulla in at least this paradigm, circulating concentrations of CAs may be altered without similar changes in plasma Met-Enk immunoreactivity. 相似文献
23.
Amanda E. Brandon Amanda C. Boyce Eugenie R. Lumbers Monika A. Zimanyi John F. Bertram Karen J. Gibson 《Anatomical record (Hoboken, N.J. : 2007)》2008,291(3):318-324
We have shown that fetuses whose mothers underwent subtotal nephrectomy (STNx) before pregnancy had high urine flow rates and sodium excretions, but lower hematocrits, plasma chloride, and plasma renin levels compared with controls. To see if these functional differences in utero persist after birth and are the result of altered renal development, we studied 8 lambs born to STNx mothers (STNxL) and 10 controls (ConL) in the second week of life. These lambs were of similar body weights, nose–rump lengths and abdominal girths. Their kidney weights were not different (ConL 36.1 ± 1.9 vs. STNxL 39.8 ± 3.3 g), nor were kidney dimensions or glomerular number (ConL 423,520 ± 22,194 vs. STNxL 429,530 ± 27,471 glomeruli). However, STNxL had 30% larger glomerular volumes (both mean and total, P < 0.01) and there was a positive relationship between total glomerular volume and urinary protein excretion (P < 0.05) in STNxL. Despite this change in glomerular morphology, glomerular filtration rate, tubular function, urine flow, and sodium excretion rates were not different between STNxL and ConL, nor were plasma electrolytes, osmolality, and plasma renin levels. Thus while many of the functional differences seen in late gestation were not present at 1–2 weeks after birth, the alteration in glomerular size and its relationship to protein excretion suggests that exposure to this altered intrauterine environment may predispose offspring of mothers with renal dysfunction to renal disease in adult life. Anat Rec, 291:318–324, 2008. © 2008 Wiley‐Liss, Inc. 相似文献
24.
In the past 6 years we have encountered 26 cases of fatal adenoviral pneumonia in six species of simian primates. O these, 22 animals were between 11 and 38 days old at the time of death, and pneumonia was the primary clinical disease. The spectrum of clinical disease varied from peracute fatal disease to inapparent disease with seroconversion. In one outbreak involving 4 infants housed together in an isolation unit, simian virus 11 was isolated from 3 of the infants and seroconversion occurred in all 4. At necropsy the lungs were voluminous, with firm gray areas of consolidation. On histopathologic examination, severe patchy necrotizing alveolitis and bronchiolitis were present. Variable edema and hyaline membrane formation, alveolar epithelial hyperplasia, and secondary bacterial pneumonia were also seen. Large basophilic intranuclear inclusions were present in bronchiolar and alveolar epithelial cells in all 26 cases. In 4 of 8 cases examined ultrastructurally typical intranuclear paracrystalline arrays of adenoviral virions were demonstrated. Intranuclear inclusion bodies were also observed occasionally in bile duct and pancreatic duct epithelium. Simian adenoviral pneumonia can be a spontaneous disease problem in laboratory-reared primates and offers excellent potential as an animal model of human adenoviral pneumonia. 相似文献
25.
Michele R Cooley Cheryl A Boyce 《Journal of clinical child and adolescent psychology》2004,33(2):210-215
Recognizing that researchers and clinicians are increasingly faced with assessing, treating, and studying ethnically, racially, and culturally diverse populations, one question is whether the appropriate tools exist. This special section aspires to advance the available assessment strategies that are appropriate for the treatment, prevention, and research of diverse children and adolescents with anxiety symptoms and disorders. This introduction presents an overview of anxiety and its disorders among multiethnic youth and identifies emerging challenges and opportunities in the assessment and treatment of anxiety symptoms and disorders among Asian American and Pacific Islander, Hispanic/Latino, African American, and European American children and adolescents within a sociocultural context. 相似文献
26.
This study observes that physicians routinely inform parents about a small minority of the medical complications and risks associated with elective circumcisions. When selecting which medical complications to mention to parents, physicians appeared to use a policy based on their subjective assessment of the frequency and seriousness of the complications' occurrence. Subsequent analyses revealed that the physicians' probability estimates were biased and their seriousness assessments were consistently less than those expressed by mothers of newborn sons. Replacing the physicians' policy of partial disclosure with a comprehensive disclosure of "unbiased" information of possible risks and complications had no effect on the mothers' decisions to have their sons circumcised but did generate numerous influences on the mothers' attitudes. Among the effects observed in mothers were a reduction in their confidence in the appropriateness of their decision and a dissatisfaction with their physician's behavior. The implications of these findings to informed consent are discussed, and a greater flexibility in providing informed consent is advocated. 相似文献
27.
Molly E. Baumann Danielle M. DeBruler Britani N. Blackstone Rebecca A. Coffey Steven T. Boyce Dorothy M. Supp J. Kevin Bailey Heather M. Powell 《Burns : journal of the International Society for Burn Injuries》2021,47(2):466-478
IntroductionDetermining the efficacy of anti-scar technologies can be difficult as qualitative, subjective assessments are often utilized instead of systematic, objective measures. Perceptions regarding the reliability of instruments for quantitative measurements along with their high cost and increased data collection time may discourage their use, leading to use of scar scales which are relatively quick and low-cost. To directly evaluate the reliability of instruments for quantitative measurements of scar properties, instruments and two qualitative scales were compared by assessing a variety of cutaneous scars.MethodsScar height and surface texture were evaluated using a 3D scanner and a mold/cast technique. Scar color was evaluated by using a spectroscopy-based tool, the Mexameter®, and digital photography with image analysis. Scar biomechanics were evaluated using the BTC-2000?, Dermal Torque Meter (DTM®), and ballistometer®. The Vancouver Scar Scale (VSS) and Patient and Observer Scar Assessment Scale (POSAS) were used to qualitatively evaluate the same scar properties. Intraclass correlation coefficients (ICC) were used to determine inter- and intra-user reliability (poor, moderate, good, excellent) with all instruments and the kappa reliability statistic was used to asses inter-user reliability (poor, fair, moderate, good, very good) for VSS and POSAS. Time for measurement collection and after collection analysis was also recorded.ResultsThe Mexameter® was the most reliable method for evaluating erythema and pigmentation compared to digital photography and image processing, POSAS and VSS. Digital photography and analysis was more reliable than POSAS and VSS. Assessment of scar height was significantly more reliable when using a 3D scanner versus VSS and POSAS. The 3D scanner and mold-cast techniques also offered an additional benefit of providing an absolute value of scar height relative to the surrounding tissue. Intra-user reliability for all mechanical tests was moderate to good. Inter-user reliability was greater when using the BTC-2000? and ballistometer® versus the DTM®. All quantitative measurements took less than 90 s for collection, with the exception of the mold/cast technique.ConclusionNon-invasive instruments allow scar properties to be quantitatively assessed with high sensitivity and as a function of time and/or treatment without the need for biopsy collection. Overall, the reliability of scar assessments was significantly improved when quantitative instruments were utilized versus scar scales. Quantitative assessment of color and biomechanics were swift, requiring less than 90 s per measurement while assessments of texture and height required additional analysis time after collection. With proper training of clinical staff and well-defined protocols for measurement collection, reliable, quantitative assessments of scar properties can be collected with little disruption to the clinical workflow. 相似文献
28.
Timotej Jagrič Christine Brown Tammy Boyce Vita Jagrič 《Health policy (Amsterdam, Netherlands)》2021,125(1):90-97
Policy-makers face pressures to improve lives and safeguard public finances sustainably. In this analysis, we estimate the economic importance of the health-care sector in 19 European national economies.We use input–output tables for the year 2010 and sectoral data to estimate a set of multipliers: simple, total, truncated, type I and type II multipliers for output, income, value-added, employment and import multiplier.The analysis reveals similarities in the economic importance of the health-care sector for the national economies of the observed countries. Results suggest prevailing positive effects on national economies (value-added, employment and household income) when spending on health-care sector products and services increases, especially in comparison to the effects of increases in spending in other sectors. The importance of the health-care sector is connected to countries’ levels of development; the benefits are especially promising in countries with lower levels of gross domestic product (GDP) per capita, where changes in the health-care sector have a larger impact on employment in the national economy than similar changes in more developed countries. The health-care sector therefore can play an important role as an instrument of economic policy. 相似文献
29.
Induction of chorea and dystonia in parkinsonian primates 总被引:1,自引:0,他引:1
S Boyce C E Clarke R Luquin D Peggs R G Robertson I J Mitchell M A Sambrook A R Crossman 《Movement disorders》1990,5(1):3-7
Administration of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine in primates induced a parkinsonian syndrome that could be reversed by levodopa treatment. Animals quickly developed an apparent restlessness ("akathisia") of the lower limbs after as little as five doses. After 4-10 weeks of regular levodopa therapy, animals developed "peak dose" choreiform movements in the lower limbs that spread, with time, to involve the upper limbs and orofacial musculature. With further treatment (5-21 months), animals developed "peak dose" dystonia that variably involved the limbs and orofacial musculature. These conditions represent novel models of levodopa-induced chorea and dystonia in humans. They depend on the same underlying neuropathology and treatment regimen as their human counterparts. It is to be anticipated that these models of dyskinesia will be useful in determining the mechanisms underlying chorea and dystonia in humans and are ideally suited for experimental evaluation of new treatment strategies. 相似文献
30.
Parasite-specific plasma immunoglobulins have been used to indicate the presence of Giardia intestinalis infection in 60 infants living in a rural area of The Gambia. Infants were studied longitudinally between 2 and 8 mo of age. The median age for first exposure to G. intestinalis was between 3 and 4 mo, and by 8 mo all but 3 infants (95%) showed a positive titer on at least one occasion. Raised Giardia-specific IgM titers were associated with reduced weight gain in the 2 wk preceding a positive titer, but catch-up growth occurred in the following 2 wk. IgM antibody titers were also positively associated with intestinal permeability (lactulose/mannitol ratio), urinary lactose excretion, plasma concentrations of alpha1-antichymotrypsin and total IgM, IgA and IgG immunoglobulins. However, infant growth over the whole 6-mo period (i.e., between 2 and 8 mo of age) was not related to mean Giardia-specific antibody titers, nor the time of first exposure to the parasite. The data suggest that giardiasis in these very young breast-fed children occurs as a mild, acute disease, and its presence could not explain the marked, long-term growth faltering observed in many of the subjects. 相似文献