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A comparison of Skirrow's, Butzler's, Blaser's, Campy-BAP and Preston media for Campylobacter spp was made using human, animal and environmental specimens. Butzler's medium gave the lowest isolation rate and Preston medium, which was the most selective, the highest isolation rate. Enrichment culture using Preston enrichment broth gave a higher isolation rate than direct plating onto Preston medium. 相似文献
5.
Pfeifer JD Ashley Hill D Ramos CV Wippold FJ II Dehner LP 《Archives of pathology & laboratory medicine》2000,124(6):898-901
A 77-year-old woman with neurofibromatosis type 1 presented with ill-fitting dentures due to intraoral extension of a right temporal fossa mass. Computed tomographic scanning demonstrated that the masticator space mass bowed the zygomatic arch and remodeled the lateral orbit and maxillary sinus walls, findings that were consistent with the clinical diagnosis of a neurofibroma with possible malignant transformation. However, light microscopic, immunohistochemical, and ultrastructural examination of tissue from an incisional biopsy specimen were diagnostic of meningioma. This case illustrates that the clinicopathologic differential diagnosis of an enlarging mass in patient with neurofibromatosis should include sporadic, unrelated neoplasms as well as tumors known to be associated with the syndrome. 相似文献
6.
Molecular characterization of gentamicin-resistant Enterococci in the United States: evidence of spread from animals to humans through food 总被引:12,自引:0,他引:12
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Donabedian SM Thal LA Hershberger E Perri MB Chow JW Bartlett P Jones R Joyce K Rossiter S Gay K Johnson J Mackinson C Debess E Madden J Angulo F Zervos MJ 《Journal of clinical microbiology》2003,41(3):1109-1113
We evaluated the molecular mechanism for resistance of 360 enterococci for which the gentamicin MICs were >/=128 micro g/ml. The aac(6')-Ie-aph(2")-Ia, aph(2")-Ic, and aph(2")-Id genes were identified by PCR in isolates from animals, food, and humans. The aph(2")-Ib gene was not identified in any of the isolates. Two Enterococcus faecalis isolates (MICs > 1,024 micro g/ml) from animals failed to generate a PCR product for any of the genes tested and likely contain a new unidentified aminoglycoside resistance gene. Pulsed-field gel electrophoresis (PFGE) analysis showed a diversity of strains. However, 1 human and 18 pork E. faecalis isolates from Michigan with the aac(6')-Ie-aph(2")-Ia gene had related PFGE patterns and 2 E. faecalis isolates from Oregon (1 human and 1 grocery store chicken isolate) had indistinguishable PFGE patterns. We found that when a gentamicin-resistant gene was present in resistant enterococci from animals, that gene was also present in enterococci isolated from food products of the same animal species. Although these data indicate much diversity among gentamicin-resistant enterococci, the data also suggest similarities in gentamicin resistance among enterococci isolated from humans, retail food, and farm animals from geographically diverse areas and provide evidence of the spread of gentamicin-resistant enterococci from animals to humans through the food supply. 相似文献
7.
Frataxin is reduced in Friedreich ataxia patients and is associated with mitochondrial membranes 总被引:17,自引:8,他引:17
Campuzano V; Montermini L; Lutz Y; Cova L; Hindelang C; Jiralerspong S; Trottier Y; Kish SJ; Faucheux B; Trouillas P; Authier FJ; Durr A; Mandel JL; Vescovi A; Pandolfo M; Koenig M 《Human molecular genetics》1997,6(11):1771-1780
Friedreich ataxia is a progressive neurodegenerative disorder caused by
loss of function mutations in the frataxin gene. In order to unravel
frataxin function we developed monoclonal antibodies raised against
different regions of the protein. These antibodies detect a processed 18
kDa protein in various human and mouse tissues and cell lines that is
severely reduced in Friedreich ataxia patients. By immunocytofluorescence
and immunocytoelectron microscopy we show that frataxin is located in
mitochondria, associated with the mitochondrial membranes and crests.
Analysis of cellular localization of various truncated forms of frataxin
expressed in cultured cells and evidence of removal of an N-terminal
epitope during protein maturation demonstrated that the mitochondrial
targetting sequence is encoded by the first 20 amino acids. Given the
shared clinical features between Friedreich ataxia, vitamin E deficiency
and some mitochondriopathies, our data suggest that a reduction in frataxin
results in oxidative damage.
相似文献
8.
Dithiothreitol prevents age-associated decrease in oocyte/conceptus viability in vitro 总被引:2,自引:0,他引:2
The present study was designed to ascertain whether the negative effects on
reproductive potential of post-ovulatory ageing in vitro of oocytes can be
prevented by antioxidant therapy. Mouse metaphase II (MII) oocytes were
aged in vitro for 12 h prior to insemination in the presence of varying
concentrations of L-ascorbic acid, 6-methoxy-
2,5,7,8-tetramethylchromane-2-carboxylic acid (Trolox), L-cystine
dihydrochloride, ethylenediaminetetraacetic acid (EDTA), beta-
mercaptoethanol and DL-dithiothreitol (DTT). In-vitro ageing of oocytes was
associated with lower fertilization rate, higher proportion of concepti
exhibiting cellular fragmentation at 24 h post-insemination and lower
percentage of concepti reaching the blastocyst stage. Ascorbic acid, Trolox
and EDTA had no effect on cellular fragmentation or potential of oocytes
for development. However, the probability of an oocyte reaching the
blastocyst stage was decreased (P < or = or = 0.05) in oocytes incubated
in the presence of L-cystine (50 and 500 microM) and beta-mercaptoethanol
(5, 50 and 500 microM) when compared to control aged oocytes.
Age-associated cellular fragmentation at 24 h post-insemination was
partially prevented (P < or = 0.05) by incubating oocytes in the
presence of beta-mercaptoethanol (500 microM). DTT (50 and 500 microM)
increased (P < or = 0.05) fertilization rate and number of cells at 81 h
post-insemination to levels similar to those exhibited by control oocytes.
Furthermore, both age-associated fragmentation at 24 h post-insemination (P
< or = 0.05) and decreased potential of oocytes for development to the
blastocyst stage (P < or = 0.05) were prevented, at least in part, by
culturing oocytes in the presence of DTT (50 microM). Although the
mechanism by which DTT exerts its beneficial effects on aged oocytes
remains to be elucidated, it may protect oocytes by preventing oxidation of
free thiol groups and/or altering a redox-independent signalling pathway
that mediates cellular fragmentation and death.
相似文献
9.
Devasia RA Varma JK Whichard J Gettner S Cronquist AB Hurd S Segler S Smith K Hoefer D Shiferaw B Angulo FJ Jones TF 《Microbial drug resistance (Larchmont, N.Y.)》2005,11(4):371-377
Multidrug-resistant Salmonella Newport with decreased susceptibility to ceftriaxone (MDR-AmpC) is becoming increasingly common in its food animal reservoirs and in humans. Few data exist on rates of antimicrobial use or differences in clinical outcomes in persons infected with MDR-AmpC or other Salmonella strains. We conducted a case-comparison analysis of data from a multistate population-based case-control study to identify antimicrobial treatment choices and differences in clinical outcomes in those infected with MDRAmpC compared to pansusceptible S. Newport. Of isolates from 215 laboratory-confirmed S. Newport cases, 54 (25%) were MDR-AmpC, 146 (68%) were pansusceptible, and 15 (7%) had other resistance patterns; 146 (68%) patients with S. Newport were treated with antimicrobial agents and 66 (33%) were hospitalized. Over two-thirds of cases at low-risk for serious complications received antimicrobial therapy, most commonly with fluoroquinolones, to which this strain was susceptible. There were no significant differences in symptoms, hospitalization, duration of illness, or other outcomes between the persons infected with MDR-AmpC and pansusceptible S. Newport. Although currently prevalent MDR-AmpC S. Newport strains remains susceptible to the antimicrobial most commonly prescribed for it, continued efforts to reduce unnecessary use of antimicrobial agents in food animals and humans are critical to prevent further development of resistance to quinolones and cephalosporins, which is likely to lead to substantial adverse outcomes. 相似文献
10.
Y chromosome microdeletions, in azoospermic or near-azoospermic subjects, are located in the AZFc (DAZ) subregion 总被引:9,自引:2,他引:9
Submicroscopic deletions of the Y chromosome and polymorphisms of the
androgen receptor (AR) gene in the X chromosome have been observed in men
with defective spermatogenesis. To further define the subregions/genes in
the Y chromosome causing male infertility and its relationship to
polymorphisms of the AR polyglutamine tract, we screened the genomic DNA of
202 subfertile males and 101 healthy fertile controls of predominantly
Chinese ethnic origin. Y microdeletions were examined with 16
sequence-tagged site (STS) probes, including the RBM and DAZ genes,
spanning the AZFb and AZFc subregions of Yq11, and related to the size of
trinucleotide repeat encoding the AR polyglutamine tract. Y microdeletions
were detected and confirmed in three out of 44 (6.8%) of azoospermic and
three out of 86 (3.5%) severely oligozoospermic patients. No deletions were
detected in any of the patients with sperm counts of >0.5 x 10(6)/ml,
nor in any of the 101 fertile controls. All six affected patients had
almost contiguous Y microdeletions spanning the entire AZFc region
including the DAZ gene. The AZFb region, containing the RBM1 gene, was
intact in five of the six subjects. Y deletions were not found in those
with long AR polyglutamine tracts. Our study, the first in a Chinese
population, suggest a cause and effect relationship between Y
microdeletions in the AZFc region (possibly DAZ), and azoospermia or
near-azoospermia. Y microdeletions and long AR polyglutamine tracts appear
to be independent contributors to male infertility.
相似文献