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41.
Evaluation of the Staph-Zym system with staphylococci isolated from bovine intramammary infections 总被引:1,自引:1,他引:1
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A total of 148 staphylococci isolated from bovine intramammary infections were used to evaluate the Staph-Zym system (ROSCO, Taastrup, Denmark). The overall accuracy of the system was 91.9%. The system correctly identified all strains of Staphylococcus aureus, Staphylococcus simulans, and Staphylococcus xylosus and 95% of Staphylococcus intermedius strains. Of 33 Staphylococcus hyicus strains, 31 (93.9%) were classified correctly by the Staph-Zym system, as well as 8 (80%) of 10 Staphylococcus chromogenes strains. All 11 Staphylococcus epidermidis strains and the 1 Staphylococcus haemolyticus strain included in the study were identified, but the Staph-Zym system had difficulty distinguishing strains of Staphylococcus warneri and Staphylococcus hominis from other species in the S. epidermidis group. The Staph-Zym system correctly identified all six S. xylosus strains and two of three Staphyloccus sciuri strains. The Staph-Zym system was considered an acceptable alternative to conventional methods for identification of bovine mammary gland isolates. 相似文献
42.
Identification of veterinary pathogens by use of commercial identification systems and new trends in antimicrobial susceptibility testing of veterinary pathogens. 总被引:4,自引:0,他引:4
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Veterinary diagnostic microbiology is a unique specialty within microbiology. Although isolation and identification techniques are similar to those used for human pathogens, many veterinary pathogens require unique cultivation or identification procedures. Commercial identification systems provide rapid, accurate identification of human pathogens. However, the accuracy of these systems with veterinary pathogens varies widely depending on the bacterial species and the host animal from which it was isolated. Increased numbers of veterinary strains or species in the data bases of the various systems would improve their accuracy. Current procedures and interpretive criteria used for antimicrobial susceptibility testing of veterinary pathogens are based on guidelines used for human pathogens. The validity of these guidelines for use with veterinary pathogens has not been established. As with fastidious human pathogens, standardized methodologies and quality control isolates are needed for tests of organisms such as Actinobacillus pleuropneumoniae and Haemophilus somnus. Furthermore, interpretive criteria for veterinary antimicrobial agents based on the MIC for veterinary pathogens, the pharmacokinetics of the antimicrobial agent in the host animal, and in vivo efficacy of the antimicrobial agent are needed. This article reviews both the commercial identification systems evaluated with veterinary pathogens and current methods for performing and interpreting antimicrobial susceptibility tests with veterinary pathogens. Recommendations for future improvements in both areas are discussed. 相似文献
43.
M. A. Helal K. C. Watts A. E. Marble 《Medical & biological engineering & computing》1993,31(6):562-568
A hydrodynamic model for the part of the human arterial network below the renal arteries has been constructed using specially
fabricated distensible tubes and a pulsatile pump to simulate an aortoiliac bypass. The experiments and the computer model
indicated that no ‘steal’ occurred due to the insertion of the bypass graft. Also, the results showed that the length of the
stenosis had a non-systematic apparent effect on the physiological significance of the obstruction and that the kinetic power
represented only a small percentage of the total power. The total power efficiency of the bypass graft was unaffected by its
elastic properties. The experimental investigation also indicated that the pressure drop across the stenosis was considerably
larger than the drop calculated using the Poiseuille flow relationship when the stenosis was severe. Therefore, a critical
arterial stenosis value cannot be defined as an obstruction of a constant percentage reduction of luminal area. It varies
directly with the effective cross-sectional area and inversely with the flow rate. The value of angiography in assessing the
functional significance of any arterial stenosis is there-fore limited. A better method for evaluation requires quantitative
measurements of local blood pressure and blood flow, not only at rest, but also under conditions creating augmented flows
due to exercise. 相似文献
44.
Disseminated cryptococcosis presenting as cellulitis with necrotizing vasculitis. 总被引:1,自引:0,他引:1
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Patients with disseminated cryptococcosis infrequently present with cutaneous involvement. Skin lesions, when present, are usually multiple and polymorphous in appearance. Cellulitis caused by Cryptococcus neoformans is rare, and necrotizing vasculitis associated with cryptococcal vascular invasion has not to our knowledge been reported. We report here a case of disseminated cryptococcosis in a renal transplant recipient who had cellulitis and necrotizing vasculitis and in whom a diagnostic skin biopsy allowed for early therapy with cure and salvage of the renal allograft. 相似文献
45.
Shaw MM Gürr WK Thackray AM Watts PA Littler E Field HJ 《Journal of virological methods》2002,102(1-2):93-102
Levels of bystander death occurring in herpes simplex virus type 1 (HSV-1)-infected mouse brain stems were studied, as well as the extent to which bystander death is influenced by guanosine nucleoside analogue treatment. Consecutive sections from brain stems of HSV-1-infected mice were stained alternately for (i) viral infection and (ii) cell death (TUNEL assay). Virus antigen was detectable in brain stems on day 3 of infection, while TUNEL staining was comparatively lower. An increase in the extent of TUNEL staining was observed on day 4 of infection. Despite this increase, however, the ratio of TUNEL-stained to infection marker-stained tissue still indicated that the amount of TUNEL staining remained lower than infection staining at this time point. On days 5 and 6 of infection, TUNEL staining continued to increase and the TUNEL/infection marker ratio switched on day 6 in favour of excess TUNEL staining, which was observed in and around the foci of infection, suggesting bystander death. The excess TUNEL staining on day 6 of infection was further increased on treatment with antivirals. The significance and implications of these results are discussed with respect to the nature and mechanism of action of the TUNEL assay, dynamics of primary HSV-1 infection, immunological influences and potential effects of antiviral treatment. The potential problems of the TUNEL assay are considered in the context of viral infection and the TUNEL assay, in combination with infection marker staining, may potentially provide a model system for quantitative analysis of true bystander death during HSV infection in vivo. 相似文献
46.
Hore J Ritchie R Watts S 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1999,125(3):302-312
Accuracy in an overarm throw requires great precision in the timing of finger opening. We tested the hypothesis that finger
opening in an overarm throw is triggered by proprioceptive feedback from elbow extension or wrist flexion. The hypothesis
was tested in two ways: first, by unexpectedly perturbing elbow extension or slowing wrist flexion and determining whether
changes occurred in finger opening, and second, by measuring the latency from the start of these joint rotations to the start
of finger opening. Subjects threw balls fast and accurately from a sitting or standing position while joint rotations were
recorded with the search-coil technique. Elbow extension was unexpectedly blocked near the start of forward motion of the
hand by a rope attached to the wrist that passed through a catch mechanism located behind the subject. In spite of a slowing
or complete block of elbow extension, and in some cases a replacement of elbow extension by elbow flexion, finger opening
always occurred and at the same latency as for normal throws. Wrist flexion was slowed in seven of eight subjects when subjects
changed from throwing with a light ball (14 g, 70 mm diam.) to a heavy ball (210 g, 65 mm diam.). For the first throw with
the heavy ball, this slowing was neither fully anticipated by the subject nor compensated for by the changed proprioceptive
feedback associated with the slowing. Consequently, the timing of finger opening was unchanged and (to the surprise of the
thrower) the ball went high. Furthermore, in unperturbed throws with tennis balls, the latency from onset of wrist flexion
or elbow extension to onset of finger opening was too short for either to have triggered finger opening (across subjects means
were 4 ms for wrist flexion and 21 ms for elbow extension). In additional analysis, no relation was found between the time
of onset of earlier occurring rotations at the shoulder and the time of onset of finger opening. We concluded that, although
a role for all proprioceptive feedback in triggering finger opening cannot be disproved by these experiments, it can be ruled
out for feedback arising from elbow extension and wrist flexion, and it seems unlikely for feedback arising from events occurring
very early in the throw. The more likely possibility is that finger opening in an overarm throw is triggered by a central
command based on an internal model of hand trajectory.
Received: 6 July 1998 / Accepted: 16 October 1998 相似文献
47.
APOE is a potential modifier gene in an autosomal dominant form of frontotemporal dementia (IBMPFD).
Sarju G Mehta Giles D J Watts Jennifer L Adamson Mike Hutton Geanie Umberger Shuling Xiong Sheena Ramdeen Mark A Lovell Virginia E Kimonis Charles D Smith 《Genetics in medicine》2007,9(1):9-13
PURPOSE: Inclusion-body myopathy, Paget's disease of bone and frontotemporal dementia is an adult-onset autosomal dominant illness (IBMPFD) caused by mutations in the valosin-containing protein (VCP) on chromosome 9p21.1-p12. The penetrance of the gene is 82% for myopathy, 49% for Paget's disease, but may be as low as 30% for frontotemporal dementia. Modifier genes could account for decreased frontotemporal dementia penetrance. In this study apolipoprotein-E (APOE) was evaluated for this role in IBMPFD families based on its known modifier effect in Alzheimer's disease. METHODS: From a database of 231 members of 15 families, 174 had APOE genotype available for analysis. Logistic regressions on APOE genotype and frontotemporal dementia were performed, using appropriate covariates. RESULTS AND CONCLUSION: FTD was associated with APOE 4 genotype (P=0.0002), myopathy (P=0.0006), and age (P=0.01), but not microtubule associated protein tau (MAPT) H2 haplotype (P=0.5) or gender (0.09) after adjustment for membership in pedigrees with at least one APOE 4 genotype. These data suggest a potential link between APOE 4 genotype and the specific form of frontotemporal dementia found in IBMPFD. The molecular basis of this link bears further investigation. We did not observe an association of frontotemporal dementia and H2 MAPT haplotype. 相似文献
48.
Positional cloning of the gene for X-linked retinitis pigmentosa 3: homology with the guanine-nucleotide-exchange factor RCC1 总被引:6,自引:7,他引:6
Roepman R; van Duijnhoven G; Rosenberg T; Pinckers AJ; Bleeker-Wagemakers LM; Bergen AA; Post J; Beck A; Reinhardt R; Ropers HH; Cremers FP; Berger W 《Human molecular genetics》1996,5(7):1035-1041
The gene for retinitis pigmentosa 3 (RP3), the most frequent form of X-
linked RP (XLRP), has been mapped previously to a chromosome interval of
less than 1000 kbp between the DXS1110 marker and the OTC locus at
Xp21.1-p11.4. Employing a novel technique, YAC Representation Hybridization
(YRH)', we have recently identified a small XLRP associated microdeletion
in this interval, as well as several putative exons including the 3' end of
a gene that was truncated by the deletion. cDNA library screening and
sequencing of a cosmid centromeric to the deletion has now enabled us to
identify numerous additional exons and to detect several point mutations in
patients with XLRP. The predicted gene product shows homology to RCC1, the
guanine-nucleotide- exchange factor (GEF) of the Ras-like GTPase Ran. Our
findings suggest that we have cloned the long-sought RP3 gene, and that it
may encode the GEF of a retina-specific GTP-binding protein.
相似文献
49.
Acidosis and blood epinephrine levels in hemorrhagic hypotension 总被引:1,自引:0,他引:1
50.
High throughput parallel analysis of hundreds of patient samples for more than 100 mutations in multiple disease genes 总被引:5,自引:0,他引:5
Shuber AP; Michalowsky LA; Nass GS; Skoletsky J; Hire LM; Kotsopoulos SK; Phipps MF; Barberio DM; Klinger KW 《Human molecular genetics》1997,6(3):337-347
As more mutations are identified in genes of known sequence, there is a
crucial need in the areas of medical genetics and genome analysis for
rapid, accurate and cost-effective methods of mutation detection. We have
developed a multiplex allele-specific diagnostic assay (MASDA) for analysis
of large numbers of samples (> 500) simultaneously for a large number of
known mutations (> 100) in a single assay. MASDA utilizes
oligonucleotide hybridization to interrogate DNA sequences. Multiplex DNA
samples are immobilized on a solid support and a single hybridization is
performed with a pool of allele-specific oligonucleotide (ASO) probes. Any
probes complementary to specific mutations present in a given sample are in
effect affinity purified from the pool by the target DNA. Sequence-specific
band patterns (fingerprints), generated by chemical or enzymatic sequencing
of the bound ASO(s), easily identify the specific mutation(s). Using this
design, in a single diagnostic assay, we tested samples for 66 cystic
fibrosis (CF) mutations, 14 beta-thalassemia mutations, two sickle cell
anemia (SCA) mutations, three Tay-Sachs mutations, eight Gaucher mutations,
four mutations in Canavan disease, four mutations in Fanconi anemia, and
five mutations in BRCA1. Each mutation was correctly identified. Finally,
in a blinded study of 106 of these mutations in > 500 patients, all
mutations were properly identified. There were no false positives or false
negatives. The MASDA assay is capable of detecting point mutations as well
as small insertion or deletion mutations. This technology is amenable to
automation and is suitable for immediate utilization for high-throughput
genetic diagnostics in clinical and research laboratories.
相似文献