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31.
Serum antibodies to JC virus, BK virus, simian virus 40, and the risk of incident adult astrocytic brain tumors. 总被引:3,自引:0,他引:3
Dana E M Rollison Kathy J Helzlsouer Anthony J Alberg Sandra Hoffman Jean Hou Richard Daniel Keerti V Shah Eugene O Major 《Cancer epidemiology, biomarkers & prevention》2003,12(5):460-463
Genomic sequences of the human polyomaviruses, JC virus (JCV) and BK virus (BKV), and simian virus 40 (SV40) have been reported from several types of human brain tumors, but there have been no population-based seroepidemiologic studies to evaluate the association between polyomavirus infection and brain tumors. We conducted a case-control study, nested within a prospective cohort, to investigate the association between antibodies to JCV, BKV, and SV40, as measured in serum collected 1-22 years before diagnosis and incident primary malignant brain tumors. Brain tumor cases (n = 44) and age-, gender-, and race-matched controls (n = 88) were identified from participants of two specimen banks in Washington County, Maryland. IgG antibodies to the capsid proteins of JCV and BKV were assessed using ELISAs. SV40-neutralizing antibodies were measured using plaque neutralization assays. Similar to the general population, the prevalence of JCV and BKV infection was high in our study population (77 and 85%, respectively). Antibodies to SV40 were less prevalent (11%). The odds ratio for subsequent brain tumor development was 1.46 [95% confidence interval (CI), 0.61-3.5] for JCV, 0.66 for BKV (95% CI, 0.22-1.95), and 1.00 for SV40 (95% CI, 0.30-3.32). Given the high prevalence of JCV and BKV infections and the millions who were potentially exposed to SV40 through contaminated polio vaccines, future studies should attempt to replicate these findings. 相似文献
32.
D. Major M. Cadenas L. Fournier S. Leclerc M. Lefebvre R. Cloutier 《Pediatric surgery international》1998,13(8):547-549
The etiology of congenital diaphragmatic hernia (CDH) is not yet known. Studies in the literature from 1941 have reported
that nutritional deficiency of vitamin A during pregnancy could lead to CDH, associated or not with other malformations in
young rats. More recently, possible correlations between expression patterns of cellular retinoid-binding protein and retinoic-acid
receptors and morphologic effects of vitamin A deficiency have been suggested. The purpose of this study was to verify in
human newborns the possible link between vitamin A deficiency and CDH previously observed in experimental animals. Blood samples
were obtained during the first hours after birth from 11 term CDH newborns and 11 healthy controls matched for gestational
age, and also from 7 mothers in each group, for a total of 7 newborn-mother pairs of matched CDH-controls. Plasma retinol
was measured by high-performance liquid chromatography and retinol-binding protein (RBP) by nephelometry. In the 11 matched
CDH-control newborns, plasma retinol and RBP levels in CDH newborns were 50% less than control values (P< 0.0002 and <0.006, respectively); in contrast, retinol levels in CDH mothers were significantly higher than those of control
mothers (P < 0.005). The observation that the plasma concentrations of retinol and RBP are low in infants with CDH relative to controls
may be clinically very relevant and may help to elucidate the mechanism of development of this congenital anomaly. 相似文献
33.
34.
H. Major J. Castro-Perez J. K. Nicholson I. D. Wilson 《Xenobiotica; the fate of foreign compounds in biological systems》2013,43(8):855-869
1. The metabolic fate of 4-bromoaniline (4-BrA) was investigated in rat following intraperitoneal administration at 50?mg kg ? 1 using HPLC-TOF-MS/MS. 2. The sensitivity provided by the use of TOF-MS/MS, aided by the distinctive isotope pattern resulting from the presence of the bromine substituent in the molecule, enabled the detection of many previously uncharacterized metabolites in the samples. 3. Several groups of minor metabolites were detected in the urine that corresponded to a number of isomeric hexose and di-hexose-containing conjugates (possibly glucosides and diglucosides) of 4-BrA. 4. As well as hexose and di-hexose conjugates of 4-BrA, several further groups of metabolites that also contained either a sulphamate or sulphate group in addition to the sugar moieties were also detected. 相似文献
35.
Andrew G. King Georgina M. Cooke Rebecca N. Johnson Richard E. Major 《Conservation Genetics Resources》2012,4(4):893-896
Using 454 pyrosequencing and multiplex genotyping we developed 18 novel microsatellite loci in Epthianura albifrons (Jardine & Selby, 1828), a small passerine threatened by loss of coastal saltmarsh. We also tested the utility of 21 previously-developed microsatellite loci from two con-familial species, however these were weakly polymorphic in E. albifrons. The 18 loci developed for E. albifrons were polymorphic with a mean of 17.1 (±2.6SE) alleles per locus. The 18 new microsatellites will be useful tools for measuring gene flow in the Endangered population of E. albifrons. 相似文献
36.
Nicole A. Kiewel Nick M. Wisdom Major R. Bradshaw Nicholas J. Pastorek 《The Clinical neuropsychologist》2013,27(6):965-974
There has been extensive research on the use of both stand-alone and embedded measures of effort in neuropsychological testing; however, relatively few studies have reported on their utility in the context of dementia. Previous studies that have examined the specificity of traditionally used cut-scores on embedded measures of effort with dementia samples have largely found high rates of false positive errors. The present study examined the specificity of several Digit Span derived embedded measures of effort in a large clinical sample of patients with probable Alzheimer's disease stratified by level of dementia severity. Of the measures that were examined, only the Vocabulary – Digit Span score demonstrated promising specificity through the moderate level of dementia severity. All of the remaining indices, including Reliable Digit Span, Digit Span Age-Corrected Scaled Score, and Longest Digits Forward (1 & 2 Trials), yielded unacceptable rates of false positive errors as dementia severity increased. The implications for these findings are discussed, including the limitations of importing methods of assessing effort from one sample to another. 相似文献
37.
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39.
Desmond A. Brown Benjamin T. Himes Brittny T. Major Benjamin F. Mundell Ravi Kumar Bruce Kall Fredric B. Meyer Michael J. Link Bruce E. Pollock John D. Atkinson Jamie J. Van Gompel W. Richard Marsh Giuseppe Lanzino Mohamad Bydon Ian F. Parney 《Mayo Clinic proceedings. Mayo Clinic》2018,93(1):16-24
Objective
To determine adverse event rates for adult cranial neuro-oncologic surgeries performed at a high-volume quaternary academic center and assess the impact of resident participation on perioperative complication rates.Patients and Methods
All adult patients undergoing neurosurgical intervention for an intracranial neoplastic lesion between January 1, 2009, and December 31, 2013, were included. Cases were categorized as biopsy, extra-axial/skull base, intra-axial, or transsphenoidal. Complications were categorized as neurologic, medical, wound, mortality, or none and compared for patients managed by a chief resident vs a consultant neurosurgeon.Results
A total of 6277 neurosurgical procedures for intracranial neoplasms were performed. After excluding radiosurgical procedures and pediatric patients, 4151 adult patients who underwent 4423 procedures were available for analysis. Complications were infrequent, with overall rates of 9.8% (435 of 4423 procedures), 1.7% (73 of 4423), and 1.4% (63 of 4423) for neurologic, medical, and wound complications, respectively. The rate of perioperative mortality was 0.3% (14 of 4423 procedures). Case performance and management by a chief resident did not negatively impact outcome.Conclusion
In our large-volume brain tumor practice, rates of complications were low, and management of cases by chief residents in a semiautonomous manner did not negatively impact surgical outcomes. 相似文献40.
Kidney renin mRNA levels in the early and chronic phases of two-kidney, one clip hypertension in the rat 总被引:2,自引:0,他引:2
The effect of clipping the left renal artery on left and right kidney renin mRNA levels during the early and chronic phases of two-kidney, one clip Goldblatt hypertension in the rat was studied. Renin mRNA levels were determined using northern and dot blotting. Four weeks after clipping, renin mRNA levels were sixfold higher in the left kidney and eightfold lower in the right kidney of the Goldblatt rats compared with the left kidney of the sham-operated rats. Similar analysis at 20 weeks after clipping showed a fourfold increase in the left kidney and a 16-fold suppression in the right kidney compared with age-matched sham-operated control rats. The study demonstrates the profound changes that occur in renin gene expression in the clipped and contralateral kidneys in this model of hypertension and shows that these changes persist into the chronic phase of the hypertension. 相似文献