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81.
Use of R-Mix Fresh Cells has been shown to be a rapid and sensitive method for the detection and identification of respiratory viruses. We prospectively evaluated the impact of incorporation of R-Mix shell vials on the sensitivity and time to detection of seven respiratory viruses recovered in a comprehensive culture during the course of an entire respiratory season in a high-volume clinical laboratory. In this study, R-Mix shell vials were used as part of the culture of 3803 respiratory specimens. A total of 428 respiratory viruses were recovered. Staining of R-Mix vials after overnight incubation allowed initial detection of 274 of 279 influenza viruses, 33 of 38 parainfluenza viruses, 35 of 51 adenoviruses, and 52 of 60 respiratory syncytial viruses (RSVs). The time to reporting of all positive cultures after in-lab specimen receipt was 2.9 days on average and those initially detected in R-Mix cells were reported in 2.3 days on average. A combination of direct fluorescent-antibody (DFA) staining and virus culture was performed on a subset of 711 respiratory specimens. Of 152 viruses identified, 57 were observed only with DFA testing (55 RSV and 2 influenza A viruses) and 31 were recovered only in cell culture. After overnight incubation, R-Mix cells detected 87.1% of respiratory viruses not observed by DFA testing and 96.9% of viruses positive by both methods. The sensitivities of DFA testing and R-Mix cells for identification of influenza viruses were 70.5% and 96.7%, respectively. The R-Mix method detected influenza virus in 18 samples that were negative by DFA testing. 相似文献
82.
Functional consequences of ROMK mutants linked to antenatal Bartter's syndrome and implications for treatment 总被引:4,自引:0,他引:4
The antenatal variant of Bartter's syndrome is an autosomal recessive
kidney disease characterized by polyhydramnios, premature delivery,
hypokalemic alkalosis and hypercalciuria. It is genetically heterogeneous,
having been linked recently to mutations in an ATP- sensitive, renal outer
medullary K+channel, ROMK, and earlier to mutations in the Na-K-2Cl
co-transporter, NKCC2. We characterized four of the mutations reported in
three heterozygous ROMK variants of antenatal Bartter's and found that each
expressed a distinct phenotype in Sf9 cells. One mutation expressed normal
function and appears to be an allelic polymorphism. The other three
mutations produced channels with significantly reduced K+fluxes. However,
the mechanisms in each case were different and reflected abnormalities in
phosphorylation, proteolytic processing or protein trafficking. The
different mechanisms may be important in the design of appropriate therapy
for patients with this disease.
相似文献
83.
Detecting pre-ovulatory luteinizing hormone surges in urine 总被引:2,自引:1,他引:2
Kesner JS; Knecht EA; Krieg EF Jr; Wilcox AJ; O'Connor JF 《Human reproduction (Oxford, England)》1998,13(1):15-21
The study objectives were to determine (i) if pre-ovulatory luteinizing
hormone (LH) surges, undetected in urine by two immunoradiometric assays
(IRMA), were detectable by an ultrasensitive immunofluorometric assay
(IFMA) and (ii) the influence of creatinine adjustment on the detection and
timing of the urinary LH surges. Daily urine specimens were contributed by
healthy 25-36 year old volunteers during 14 ovulatory menstrual cycles for
an epidemiological study conducted in 1983-1985. Specimens were selected as
having been previously assayed by two IRMA without consistently detecting
LH surges. These urine specimens were remeasured using an IFMA and adjusted
for creatinine concentration. IFMA measurements revealed unambiguous LH
surges in all cycles. Adjusting IRMA urinary LH values for creatinine
concentrations revealed previously undetected LH surges in four of eight
cycles. Creatinine adjustment also altered the timing of IRMA and IFMA LH
surges by 1-5 days. These results demonstrate an IFMA that detects pre-
ovulatory LH surges in unpreserved, frozen urine from cycles where such
surges were previously undetectable. Further, creatinine adjustment can
markedly affect detection and timing of the onset and peak of the urinary
LH surge. While our analysis suggests that this adjustment improves the
validity of the LH measure, this requires further investigation.
相似文献
84.
85.
Chemoreceptors in the ventral medulla contribute to the respiratory response to hypercapnia. Do they ‘sense’ intracellular pH (pHi)? We measured pHi in the ventral medulla or cortex (control) using 31P-NMR obtained via a novel 3×5 mm2 surface coil in anesthetized rats breathing air or 7% CO2. During air breathing over 240 min, pHi decreased slightly from 7.13±0.02 to 7.05±0.02 (SEM; n=5; 2 cortex, 3 ventral medulla). During 180 min of hypercapnia, cortical pHi (n=4) decreased from 7.17±0.02 to 6.87±0.01 by 90 min and recovered by 150 min. Ventral medulla pHi showed no such regulation. It decreased from 7.11±0.02 to 6.88±0.02 at 90 min and recovered only after cessation of hypercapnia (n=5), results consistent with pHi being the chemoreceptor stimulus. However, non-chemoreceptor neurons that contribute to our medullary NMR signal also do not appear to regulate pHi in vitro. Regional differences in pHi regulation between cortex and ventral medulla may be due to both chemosensitive and non-chemosensitive neurons. 相似文献
86.
87.
Gregory J. Sengstock Kevin B. Johnson Paul T. Jantzen Edwin M. Meyer Adrian J. Dunn Gary W. Arendash 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1992,90(1):163-174
Summary Ibotenic acid was infused into the nucleus basalis magnocellularis (nBM) of 2-day old rats to eliminate immature cholinergic neurons before they develop functional synaptic connections in the neocortex. For bilaterally lesioned neonates, cognitive testing was initiated 2 months after lesioning and animals were sacrificed at 8 or 12 months of age. Lesioned animals exhibited a marked deficit in the retention of passive avoidance behavior, as well as in the acquisition of 2-way active avoidance behavior. Lesioned animals also made significantly more alternation errors than control animals in the Lashley III spatial maze and showed severe impairments in general learning, reference memory and working memory during 17-arm radial maze testing. For all 4 tasks, neonatally lesioned animals did not show any recovery to the performance level of control animals. Histological analysis of the subcortex from lesioned animals during adulthood revealed: (1) a substantial reduction in acetylcholinesterase-positive cells (presumably cholinergic) within the nucleus basalis, (2) decreased acetylcholinesterase staining in neocortex and (3) a gliosis essentially restricted to the globus pallidus. Surrounding brain regions were apparently not damaged as a direct result of excitotoxin infusion. Neurochemically, neonate nBM lesioning produced a long term cholinergic hypofunction as evidenced by significant reductions of 25% and 18% in frontal cortex chorine acetyltransferase (CAT) activity at 12 and 8 months of age, respectively. By contrast, prefrontal cortical concentrations of biogenic amines and their metabolites were unaffected, thus indicating a degree of neurochemical specificity for these neonatal nBM lesions. The persistant cortical cholinergic hypofunction in lesioned animals may be related to the long term deficits in learning/memory abilities that were also observed. It is suggested that neonatal nBM lesioning could provide a useful animal model for elucidating the plasticity of the developing brain after cortical anervation. 相似文献
88.
Davey S Carter V Goodman R Day S Brown C Morris J Key T Bendukidze N Dunn PP 《Tissue antigens》2005,65(5):485-487
A novel allele, human leukocyte antigen (HLA)-A*6824, has been identified in three unrelated individuals of northwestern European origin in a period of less than 4 months, implying that this allele may be quite common in this population. HLA-A*6824 differs from A*680102 by a single nucleotide change at position 275 in exon 2, which results in a conservative amino acid substitution from lysine to arginine in the peptide-binding groove at codon 68. 相似文献
89.
We have identified a new HLA-B*15 allele (B*1569) by polymerase chain reaction (PCR) using sequence-specific primers (SSP) and sequence-based typing (SBT). This novel allele was found in a 67-year-old white Caucasian male and differs from HLA-B*1503 at 3 positions. The nucleotide substitutions at positions 544, 559 and 560 result in amino acid changes at codon 158 from GCC (alanine) to ACC (threonine), and at codon 163 from CTG (leucine) to ACG (threonine). 相似文献
90.