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11.
12.
Phagocyte function and cytokine production in community acquired pneumonia. 总被引:8,自引:3,他引:5
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K Moussa H J Michie I A Cree A C McCafferty J H Winter D P Dhillon S Stephens R A Brown 《Thorax》1994,49(2):107-111
BACKGROUND--It is possible that many deaths from pneumonia may involve the generation of inflammatory mediators and tissue damage by activated phagocytes. To test this hypothesis phagocyte function, plasma levels of interleukin 6 (IL-6), tumour necrosis factor alpha (TNF alpha), and soluble interleukin 2 receptor (IL-2R), disease severity, and outcome have been examined in 46 patients with community acquired pneumonia. METHODS--Polymorphonuclear leucocyte (PMNL) and monocyte function were measured daily by chemiluminescence in these patients during the first week of admission, and cytokine levels were subsequently determined by ELISA. A series of 61 healthy individuals were used as a control group for the chemiluminescence results. RESULTS--There was evidence of phagocyte, particularly PMNL, activation on admission in 76% of the patients. Most patients (86%) also had raised IL-2R levels on admission. IL-6 and unbound TNF alpha were present in 23% and 41% of patients at varying times during the course of the disease. There was little correlation between measurements of cytokine or phagocyte levels and outcome or indicators of disease severity, although this may be because of the small number of patients included in this preliminary study. CONCLUSIONS--These results are consistent with the hypothesis that activated phagocyte function and raised levels of circulating cytokines may contribute to the pathogenesis of community acquired pneumonia. There are striking similarities in this respect between pneumonia, adult respiratory distress syndrome, and sepsis. 相似文献
13.
R S Dhillon 《Journal of the Royal Society of Medicine》1988,81(12):710-713
A multicentre prospective trial was commenced in July 1984 to establish the incidence of otitis media with effusion (OME) in children born with a cleft of the palate. Additionally, the data recorded would allow an assessment of the effect of palatal closure on middle ear function. Prior to palatal closure, 97% of ears in a group of 50 patients had otitis media with effusion (OME). The insertion of a long-term ventilation tube provided a means of aeration of one ear with the non-ventilated ear acting as a control. Eighty percent of control ears had persistent OME during a 24-month follow-up period post palatal repair. It would seem that OME is universally present in children with a cleft palate prior to 4 months of age and this incidence is only marginally diminished by palatal surgery. The liaison between plastic surgical and ENT units should be even closer than before in order to manage these patients satisfactorily. 相似文献
14.
Focal reduction of villous blood flow in early indomethacin
enteropathy: a dynamic vascular study in the rat 总被引:3,自引:0,他引:3
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Background—Oral indomethacin causes villousshortening, microvascular damage, and distortion, which might inducemucosal ischaemia and necrosis.
Aims—In order to determine the early events inindomethacin induced jejunal injury we examined the temporal relationsbetween morphological damage and changes in villous blood flowfollowing indomethacin.
Methods—In anaesthetised rats, mid jejunal villiwere exteriorised in a chamber and observed by fluorescence microscopy.Blood flow in surface capillaries was calculated from velocities and diameters. Indomethacin was applied by both luminal and intravenous routes for 90 minutes, after which the animal was perfusion fixed andthe villi were processed for histological examination. Control animalsreceived intravenous or luminal bicarbonate (1.25%).
Results—Blood flow slowed in individual villi at20 minutes, and progressed to complete stasis (in another group) by 45 minutes. Histological examination at 20 minutes revealed microvascular distortion, but no villous shortening: crypt depth:villous height ratios were 0.356 (0.02) in test and 0.386 (0.01) in surrounding villi(p>0.5). At stasis, the villi under study showed epithelial clumpingand were shortened: crypt depth:villous height ratios were 0.92 (0.2)in test and 0.42 (0.06) in surrounding villi (p<0.02). Vehicle alonehad no effect on either blood flow or histology.
Conclusions—Focal slowing of villous blood flowand microvascular distortion precede villus shortening and epithelialdisruption, and indicate that damage to surface microvasculature is anearly event in indomethacin induced mucosal injury in this model.
Aims—In order to determine the early events inindomethacin induced jejunal injury we examined the temporal relationsbetween morphological damage and changes in villous blood flowfollowing indomethacin.
Methods—In anaesthetised rats, mid jejunal villiwere exteriorised in a chamber and observed by fluorescence microscopy.Blood flow in surface capillaries was calculated from velocities and diameters. Indomethacin was applied by both luminal and intravenous routes for 90 minutes, after which the animal was perfusion fixed andthe villi were processed for histological examination. Control animalsreceived intravenous or luminal bicarbonate (1.25%).
Results—Blood flow slowed in individual villi at20 minutes, and progressed to complete stasis (in another group) by 45 minutes. Histological examination at 20 minutes revealed microvascular distortion, but no villous shortening: crypt depth:villous height ratios were 0.356 (0.02) in test and 0.386 (0.01) in surrounding villi(p>0.5). At stasis, the villi under study showed epithelial clumpingand were shortened: crypt depth:villous height ratios were 0.92 (0.2)in test and 0.42 (0.06) in surrounding villi (p<0.02). Vehicle alonehad no effect on either blood flow or histology.
Conclusions—Focal slowing of villous blood flowand microvascular distortion precede villus shortening and epithelialdisruption, and indicate that damage to surface microvasculature is anearly event in indomethacin induced mucosal injury in this model.
Keywords:indomethacin; jejunum; villi; microcirculation; endothelium; microthrombi
相似文献15.
Comparison of serum hepatitis C virus RNA and core antigen concentrations and determination of whether levels are associated with liver histology or affected by specimen storage time
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Lagging LM Garcia CE Westin J Wejstål R Norkrans G Dhillon AP Lindh M 《Journal of clinical microbiology》2002,40(11):4224-4229
An enzyme immunoassay has recently been developed for the hepatitis C virus (HCV) core antigen. To evaluate the possible association between core antigen and HCV RNA levels with regards to the change in liver histology over time as well as study the effect of duration of storage on viral load results, sequential sera were analyzed from 45 patients with chronic HCV infection who had undergone two or more liver biopsies. A relatively strong association was found between the core antigen and HCV RNA concentrations (r(s) = 0.8), with a core antigen level of 1 pg/ml corresponding to approximately 1,000 IU/ml. All 42 sera with detectable HCV RNA at the time of the second biopsy had core antigen concentrations above 1 pg/ml, and the three sera without detectable HCV RNA had concentrations below 1 pg/ml. No association was found between HCV RNA or core antigen levels and the stage of fibrosis in biopsy samples, progression of fibrosis, necro-inflammatory grade, steatosis, genotype, alanine aminotransferase level, or alcohol consumption. A significant association was demonstrated between the storage time of the samples and both the HCV RNA and core antigen concentrations. The median log HCV RNA concentrations (international units/milliliter) were 3.92 for the sera obtained at the time of the first biopsy (median storage time, 13.0 years) and 4.41 for the sera obtained at the time of the second biopsy (median storage time, 6.6 years) compared to 5.96, the median for 102 different routine clinical patient samples. 相似文献
16.
17.
Androgen receptor YAC transgenic mice carrying CAG 45 alleles show trinucleotide repeat instability 总被引:1,自引:15,他引:1
La Spada AR; Peterson KR; Meadows SA; McClain ME; Jeng G; Chmelar RS; Haugen HA; Chen K; Singer MJ; Moore D; Trask BJ; Fischbeck KH; Clegg CH; McKnight GS 《Human molecular genetics》1998,7(6):959-967
X-linked spinal and bulbar muscular atrophy (SBMA) is caused by a CAG
repeat expansion in the first exon of the androgen receptor (AR) gene.
Disease-associated alleles (37-66 CAGs) change in length when transmitted
from parents to offspring, with a significantly greater tendency to shift
size when inherited paternally. As transgenic mice carrying human AR cDNAs
with 45 and 66 CAG repeats do not display repeat instability, we attempted
to model trinucleotide repeat instability by generating transgenic mice
with yeast artificial chromosomes (YACs) carrying AR CAG repeat expansions
in their genomic context. Studies of independent lines of AR YAC transgenic
mice with CAG 45 alleles reveal intergenerational instability at an overall
rate of approximately 10%. We also find that the 45 CAG repeat tracts are
significantly more unstable with maternal transmission and as the
transmitting mother ages. Of all the CAG/CTG repeat transgenic mice
produced to date the AR YAC CAG 45 mice are unstable with the smallest
trinucleotide repeat mutations, suggesting that the length threshold for
repeat instability in the mouse may be lowered by including the appropriate
flanking human DNA sequences. By sequence-tagged site content analysis and
long range mapping we determined that one unstable transgenic line has
integrated an approximately 70 kb segment of the AR locus due to
fragmentation of the AR YAC. Identification of the cis - acting elements
that permit CAG tract instability and the trans -acting factors that
modulate repeat instability in the AR YAC CAG 45 mice may provide insights
into the molecular basis of trinucleotide repeat instability in humans.
相似文献
18.
19.
20.
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