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1.
Pulmonary oxidative stress response in young children with cystic fibrosis 总被引:4,自引:3,他引:1 下载免费PDF全文
BACKGROUND: It has been suggested that oxidative stress contributes to lung injury in cystic fibrosis. There is, however, no direct evidence of increased pulmonary oxidative stress in cystic fibrosis nor of the effects of inflammation on the major pulmonary antioxidant, glutathione. A study was undertaken to measure these parameters in infants and young children in the presence or absence of pulmonary inflammation. METHODS: Thirty two infants and young children with cystic fibrosis of mean (SD) age 21.4 (15.3) months (range 2-54) and seven non-cystic fibrosis control subjects of mean (SD) age 21.0 (21.2) months (range 2-54) were studied using bronchoalveolar lavage (BAL). On the basis of the BAL findings the cystic fibrosis group was divided into those with (CF-I) and those without pulmonary inflammation (CF- NI). Levels of lipid hydroperoxide, total glutathione, and gamma- glutamyl transpeptidase (gamma-GT) were then measured in the BAL fluid. RESULTS: The concentrations of lipid hydroperoxide and gamma-GT in the epithelial lining fluid were significantly increased in the CF-I group compared with the control and CF-NI groups, each of which had similar values for these parameters (ratio of geometric means for CF-I group versus control for lipid hydroperoxide 5.4 (95% confidence interval (CI) 1.8 to 15.8) and for gamma-GT 5.2 (95% CI 1.4 to 19.4)). The glutathione concentration tended to be lower in the CF-I subjects but the difference did not reach statistical significance. CONCLUSIONS: These results demonstrate that the airways in patients with cystic fibrosis are exposed to increased oxidative stress which appears to be a consequence of pulmonary inflammation rather than part of the primary cystic fibrosis defect. The increase in gamma-GT in the CF-I group suggests a mechanism by which extracellular glutathione could be utilised by airway epithelial cells.
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2.
B. J. Young R. O’Regan F. Kinsella A. Benedict-Smith M. McDermott M. Hillery L. M. T. Collum M. Hickey-Dwyer P. Mullaney J. Blake M. Hope-Ross S. Travers D. Mooney P. S. Phelan P. E. Cleary D. F. P. Larkin D. Roden P. Eustace H. N. O’Donoghue J. D. McAdoo J. G. Madden J. P. Burke M. O’Keefe R. Bowell M. O’Sullivan P. T. McLister D. J. Wilson J. Walsh 《Irish journal of medical science》1988,157(3):91-94
3.
Relative carriage rates of nuclear dehydrogenating clostridia in two populations of different colorectal cancer risk 下载免费PDF全文
Carriage of nuclear dehydrogenating clostridia has been associated with colon cancer and implicated in its aetiology. This study has compared the carriage of these organisms in a British population at high risk for the development of colon cancer with a low risk Nigerian population. Clostridia were found in all of the stools from both populations. Nuclear dehydrogenating clostridia were only found in the stools of the British subjects (32%). These results support the suggestion that the carriage rate of nuclear dehydrogenating clostridia in a population is related to the risk of colon cancer. 相似文献
4.
Shadlen MF Larson EB Wang L Phelan EA McCormick WC Jolley L Teri L van Belle G 《Neurobiology of aging》2005,26(1):17-24
OBJECTIVES: To assess the influence of education on the association between apolipoprotein E and cognitive change. DESIGN: Prospective cohort. PARTICIPANTS: HMO-based sample of 2168 non-demented community-dwelling elderly followed over 6 years. MEASUREMENTS: Generalized estimating equations were used with the difference between baseline and follow-up cognitive abilities screening instrument (CASI) as the outcome variable. RESULTS: At follow-up, 6% of the sample had a decline of 1.5 S.D. or greater on the CASI. Compared to individuals without an APOE4 allele, individuals with a single APOE4 allele did not have greater CASI decline. By contrast, individuals with two APOE4 alleles experienced greater decline in cognitive performance and the magnitude of that decline decreased as years of educational attainment increased. These relationships held after adjusting for age, gender, ethnicity, depression, diabetes, and history of vascular disease. CONCLUSION: Lower education was associated with steep 4-year cognitive decline for APOE4 homozygotes but not for APOE4 heterozygotes. Potentially modifiable host factors such as education could influence the association of high-risk genotypes and cognitive decline. 相似文献
5.
Development of hatching blastocysts from immature human oocytes following in-vitro maturation and fertilization using a co-culture system 总被引:8,自引:0,他引:8
Hwu YM; Lee RK; Chen CP; Su JT; Chen YW; Lin SP 《Human reproduction (Oxford, England)》1998,13(7):1916-1921
Recently, in-vitro maturation (IVM) of immature human oocytes recovered
from non-stimulated follicles has been applied in the treatment of
infertility. However, in previous reports, very few embryos cultured in
conventional medium have reached the expanded blastocyst stage following
in-vitro maturation and fertilization (IVM/IVF). The objective of this
study was to investigate whether the developmental competence of human
embryos following IVM/IVF could be enhanced by the use of a human ampullary
cell co-culture system. Immature human oocytes were aspirated from small
follicles at Caesarean section and then cultured in medium containing human
menopausal gonadotrophin for 36 to 48 h, followed by insemination. Zygotes
were randomly cultured either in conventional culture medium alone or in
the co-culture system. Of 48 embryos cultured in conventional medium alone,
all arrested at the 2-16- cell stage on day 3 after insemination. Of 46
embryos cultured in the co-culture system, 26 embryos (56.5%) arrested at
the 2-16-cell stage. Six embryos (13%) developed to the morula stage.
Fourteen embryos (30.4%) developed to expanded blastocysts and two
blastocysts were hatching on day 7 after insemination. We conclude that
co-culture significantly enhances the development of blastocysts in embryos
resulting from IVM/IVF.
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6.
Detection of chromosomes and estimation of aneuploidy in human spermatozoa using fluorescence in-situ hybridization 总被引:11,自引:0,他引:11
The development and application of fluorescence in-situ hybridization
(FISH) has opened the way for comprehensive studies on numerical chromosome
abnormalities in human spermatozoa. FISH can be rapidly applied to large
numbers of spermatozoa and thus overcomes the major limitation of
karyotyping spermatozoa after penetration of zona-free hamster oocytes. The
simultaneous hybridization of two or more chromosome-specific probes to
spermatozoa and subsequent detection of the bound probes using different
fluorescent detection systems enables two or more chromosomes to be
localized simultaneously in the same spermatozoon and provides a technique
for undertaking reasonable estimates of aneuploidy. The most commonly used
probes are those which bind to the centromeric region of specific
chromosomes. Most studies to date have concentrated on estimating
aneuploidy in spermatozoa from normospermic men, although reports are
beginning to appear on aneuploidy in spermatozoa from subfertile and
infertile men. Multi- probe FISH studies have generally reported disomy
(hyperhaploidy) estimates of 0.05-0.2% per chromosome. There is preliminary
evidence that some chromosomes such as X, Y and 21 are predisposed towards
higher rates of non-disjunction during spermatogenesis. There are also
suggestions of inter-donor variability in aneuploidy frequencies for
specific chromosomes, although this requires confirmation in larger
studies. While FISH is clearly a powerful technique that has many
applications in reproductive medicine, it must also be realized that it
does have limitations and the technology itself is still evolving and has
yet to be fully validated on spermatozoa.
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7.
Preliminary observations on polar body extrusion and pronuclear formation in human oocytes using time-lapse video cinematography 总被引:10,自引:17,他引:10
Payne D; Flaherty SP; Barry MF; Matthews CD 《Human reproduction (Oxford, England)》1997,12(3):532-541
In this study, we have used time-lapse video cinematography to study
fertilization in 50 human oocytes that had undergone intracytoplasmic sperm
injection (ICSI). Time-lapse recording commenced shortly after ICSI and
proceeded for 17-20 h. Oocytes were cultured in an environmental chamber
which was maintained under standard culture conditions. Overall, 38 oocytes
(76%) were fertilized normally, and the fertilization rate and embryo
quality were not significantly different from 487 sibling oocytes cultured
in a conventional incubator. Normal fertilization followed a defined course
of events, although the timing of these events varied markedly between
oocytes. In 35 of the 38 fertilized oocytes (92%), there were circular
waves of granulation within the ooplasm which had a periodicity of 20-53
min. The sperm head decondensed during this granulation phase. The second
polar body was then extruded, and this was followed by the central
formation of the male pronucleus. The female pronucleus formed in the
cytoplasm adjacent to the second polar body at the same time as, or
slightly after, the male pronucleus, and was subsequently drawn towards the
male pronucleus until the two abutted. Both pronuclei then increased in
size, the nucleoli moved around within the pronuclei and some nucleoli
coalesced. During pronuclear growth, the organelles contracted from the
cortex towards the centre of the oocyte, leaving a clear cortical zone. The
oocyte decreased in diameter from 112 to 106 microm (P < 0.0001) during
the course of the observation period. The female pronucleus was
significantly smaller in diameter than the male pronucleus (24.1 and 22.4
microm respectively, P = 0.008) and contained fewer nucleoli (4.2 and 7.0
respectively, P < 0.0001). After time-lapse recording, oocytes were
cultured for 48 h prior to embryo transfer or cryopreservation. Embryo
quality was related to fertilization events and periodicity of the
cytoplasmic wave, and it was found that good quality embryos arose from
oocytes that had more uniform timing from injection to pronuclear abuttal
and tended to have a longer cytoplasmic wave. In conclusion, we have shown
that time-lapse video cinematography is an excellent tool for studying
fertilization and early embryo development, and have demonstrated that
human fertilization comprises numerous complex dynamic events.
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8.
Projection neurons in the rat dorsolateral septal nucleus (DLSN) were labeled intracellularly with horseradish peroxidase (HRP) in an in vitro slice preparation. The labeled neurons exhibited widespread 'isodendritic' type dendritic fields. Each of the neurons was identified as a projection neuron by the tracing of its main axon out of DLSN. The axons of these neurons gave rise to intrinsic collaterals which branched to form an extensive axon plexus which was confined to DLSN. These axon collaterals exhibited numerous en passant swellings suggestive of boutons. It is proposed that the recurrent axon collaterals of DLSN projection neurons may form an anatomical substrate for local inhibition within DLSN. 相似文献
9.
10.
AIMS: To assess the accuracy and precision of measuring haemoglobin A(2) by high performance liquid chromatography (HPLC) in the presence and absence of sickle cell trait, with or without alpha thalassaemia trait. METHODS: The haemoglobin A(2) percentage and the haemoglobin A(2) plus S percentages were determined by HPLC on 82 normal controls and 78 patients with sickle cell trait, respectively; the alpha thalassaemia status of each patient was determined by polymerase chain reaction. Red cell indices and haemoglobin A(2) and S percentages were compared in patients with two, three, or four alpha genes. RESULTS: Of the 78 patients with sickle cell trait, 17 were heterozygous for alpha(+) thalassaemia (-alpha(3.7)/alphaalpha) and 13 were homozygous (-alpha(3.7)/-alpha(3.7)). Microcolumn chromatography showed that the haemoglobin A(2) percentage was slightly, but significantly, higher than normal in sickle cell trait. HPLC determinations of haemoglobin A(2) percentage in patients with sickle cell trait are precise but inaccurate, the percentage being appreciably overestimated. The measured haemoglobin A(2) percentage is stable for one week, but inaccuracy increases by two weeks in most samples. Despite this inaccuracy, there are significant differences in the HPLC "haemoglobin A(2) percentage" between groups of individuals with two, three, and four alpha genes. CONCLUSIONS: Haemoglobin A(2) determinations by HPLC are precise but inaccurate. Nevertheless, there are significant differences in the haemoglobin A(2) percentage in subjects with two, three, and four alpha genes. Although there is some overlap between groups, this can be useful, together with the red cell indices, in predicting the likelihood of coexisting alpha thalassaemia. 相似文献