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1.
Peiwen Pan Mari Leppilampi Silvia Pastorekova Jaromir Pastorek Abdul Waheed William S. Sly Seppo Parkkila 《The Journal of physiology》2006,571(2):319-327
Using real-time PCR and immunohistochemistry, we have examined the expression of carbonic anhydrase isozymes (CA) I, II, III, IV, IX, XII, XIII and XIV in the brain, kidney, stomach and colon of the wild-type, CA II-deficient ( Car2−/− ), and CA IX deficient ( Car9−/− ) mice. The expression of Car4, Car12, Car13 and Car14 mRNAs did not show any significant deviations between the three groups of mice, whereas both groups of CA deficient mice showed decreased expression levels of Car1 in the colon and Car3 in the kidney. The Car2 mRNA level was greatly reduced but not completely abolished in all four tissues from the Car2−/− mice in which no CA II protein was expressed. Sequencing the Car2 cDNA isolated from C57BL6 Car2−/− mice revealed two nucleotide differences from the wild-type C57BL6 mice. One is a silent polymorphism found in Car2 mRNA from wild-type DBA mice, which is the strain that provided the original mutagenized chromosome. The second change is a mutation that causes prematurely terminated translation at codon 155 (Gln155X). Car9 mRNA and CA IX protein expression levels were up-regulated about 2.5- and 3.6-fold, respectively, in the stomach of the Car2−/− mice. These results suggest that the loss of function of cytosolic CA II in the stomach of Car2−/− mice leads to up-regulation of an extracellular CA, namely CA IX, which is expressed on the cell surface of the gastric epithelium. 相似文献
2.
H E Broxmeyer D E Williams H S Boswell S Cooper R K Shadduck S Gillis A Waheed D L Urdal 《Immunobiology》1986,172(3-5):168-174
The influence of purified natural colony stimulating factor-1 (CSF-1), purified recombinant granulocyte-macrophage (GM)-CSF, purified recombinant interleukin 3 (IL3) and natural IL3 were assessed in mice that were untreated or pretreated with purified iron-saturated human lactoferrin (LF) in order to first suppress myelopoiesis in the mice. S1/S1d mice responded to recombinant GM-CSF and recombinant IL3 in a manner similar to the response of their +/+ littermates. These 4 factors increased the cycling status of hematopoietic progenitors in vivo. The effects were more noticeable if myelopoiesis was first decreased by LF. The effects do not appear to be due to endotoxin contamination. It cannot be discerned from these studies whether the effects are direct ones on the progenitor cells or indirect ones mediated through growth-factor releasing accessory cells. It is possible that effects can be both direct and indirect. 相似文献
3.
The effects of interleukins and other soluble factors on T-lymphocyte colony formation. 总被引:1,自引:0,他引:1
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When plated in semi-solid media, PHA-stimulated human peripheral blood mononuclear cells (PBMC) form discrete T-cell colonies. By contrast, Sephadex G-10 non-adherent (NA) cells (greater than 96% T lymphocytes) show virtually no clonal growth unless cocultured with soluble factors derived from either normal adherent cells or tumour cell lines. Purified IL-1 was able to initiate colony growth of mitogen-stimulated NA cells; cultures containing 20 U of human IL-1 yielded colony counts that were only slightly less than those with PBMC. In addition, recombinant IL-2, free of measurable IL-1, was able to provide the initiating signal required for clonal expansion. Both recombinant and lymphocyte-derived IL-2 were able to enhance the clonal growth of PBMC. Colony growth could be initiated by supernatants derived from short-term cultures of either monocytic (U937, HL60) or B-cell (Raji, Daudi) tumour cell lines. The abilities of these tumour cell lines to promote clonal responses did not correlate with their contents of either IL-1 or IL-2. By contrast, supernatants derived from either K562 (an erythroleukaemic line) or MOLT 4 (a T-cell lymphoma) cells did not provide the initiating signal. 相似文献
4.
Filippi M Rocca MA Wiessmann M Mennea S Cercignani M Yousry TA Sormani MP Comi G 《AJNR. American journal of neuroradiology》1999,20(10):1931-1938
BACKGROUND AND PURPOSE: Fast fluid-attenuated inversion-recovery (FLAIR) sequences are sensitive for detecting lesions in patients with multiple sclerosis (MS). More rapid fast-FLAIR imaging of the brain can be achieved by the concomitant use of half-Fourier acquisition single-shot turbo spin-echo (HASTE-FLAIR) and echo-planar imaging (EPI-FLAIR). The present study was performed in a large cohort of subjects to assess and compare the number and volume of brain lesions detected by the fast-FLAIR, HASTE-FLAIR, and EPI-FLAIR sequences in patients with MS. METHODS: Fast-FLAIR, HASTE-FLAIR, and EPI-FLAIR sequences were obtained from 46 consecutive MS patients. Lesions seen on each type of sequence were counted and classified by consensus by two observers. Lesion volumes were measured using a semiautomated segmentation technique based on local thresholding. RESULTS: The quality of the fast-FLAIR images was significantly better than that of HASTE-FLAIR and EPI-FLAIR images. Fast-FLAIR revealed significantly more lesions and higher lesion volumes than did HASTE-FLAIR and EPI-FLAIR. A similar number of large lesions was detected by the three sequences, but HASTE-FLAIR and EPI-FLAIR showed significantly fewer small and intermediate lesions than did fast-FLAIR. The number of lesions seen on HASTE-FLAIR and EPI-FLAIR images was similar. CONCLUSION: HASTE-FLAIR and EPI-FLAIR sequences revealed as many large MS lesions as fast-FLAIR. Because their acquisition times are only a fraction of that needed for fast-FLAIR sequences, they may be useful for making a rapid diagnosis of MS in uncooperative patients. Their reduced ability to detect smaller lesions indicates that they should not be used as a routine approach to imaging patients with MS. 相似文献
5.
The use of magnetic resonance imaging in multiple sclerosis treatment trials: power calculations for annual lesion load measurement 总被引:1,自引:0,他引:1
Molyneux PD Miller DH Filippi M Yousry T Kappos L Gasperini C Adèr HJ Barkhof F 《Journal of neurology》2000,247(1):34-40
Phase III definitive treatment trials of new multiple sclerosis (MS) therapies now routinely incorporate an annual magnetic
resonance imaging protocol, with change in T2-weighted brain lesion load providing an important outcome measure. To date the
accepted strategy has been to perform a core imaging protocol on all patients in such studies. The aim of this study was to
provide power calculations based on this MRI endpoint. Serial MRI data from 128 patients with either relapsing remitting (RR)
or secondary progressive (SP) MS were used to calculate sample size requirements using a repeated measures analysis of variance
design. We provide sample size calculations based on various follow-up intervals and effect sizes. Sample sizes for the SPMS
cohort were substantially larger than for the RRMS group, reflecting the greater variance in lesion load changes between patients
in the SPMS group. With a follow-up of 3 years, we estimate that only 12 and 33 patients per arm are needed to show stabilisation
of MRI lesion load in the RRMS and SPMS groups, respectively. Our results suggest that ongoing phase III treatment trials
are more than adequately powered to detect even subtle treatment effects, and indicate that incorporating measurements from
longer follow-up durations increases power substantially. We conclude that an annual imaging protocol provides a robust and
powerful tool for assessing effects on the radiological appearance of the disease process.
Received: 11 February 1999/Received in revised form: 28 July 1999/Accepted: 10 October 1999 相似文献
6.
Visualization of cranial nerves I–XII: value of 3D CISS and T2-weighted FSE sequences 总被引:5,自引:0,他引:5
Yousry I Camelio S Schmid UD Horsfield MA Wiesmann M Brückmann H Yousry TA 《European radiology》2000,10(7):1061-1067
The aim of this study was to evaluate the sensitivity of the three-dimensional constructive interference of steady state
(3D CISS) sequence (slice thickness 0.7 mm) and that of the T2-weighted fast spin echo (T2-weighted FSE) sequence (slice thickness
3 mm) for the visualization of all cranial nerves in their cisternal course. Twenty healthy volunteers were examined using
the T2-weighted FSE and the 3D CISS sequences. Three observers evaluated independently the cranial nerves NI–NXII in their
cisternal course. The rates for successful visualization of each nerve for 3D CISS (and for T2-weighted FSE in parentheses)
were as follows: NI, NII, NV, NVII, NVIII 40 of 40 (40 of 40), NIII 40 of 40 (18 of 40), NIV 19 of 40 (3 of 40), NVI 39 of
40 (5 of 40), NIX, X, XI 40 of 40 (29 of 40), and NXII 40 of 40 (4 of 40). Most of the cranial nerves can be reliably assessed
when using the 3D CISS and the T2-weighted FSE sequences. Increasing the spatial resolution when using the 3D CISS sequence
increases the reliability of the identification of the cranial nerves NIII–NXII.
Received: 29 September 1999; Revised: 2 February 2000; Accepted: 21 March 2000 相似文献
7.
8.
Luke A. Massey MRCP Caroline Micallef MD FRCR Dominic C. Paviour PhD Sean S. O'Sullivan PhD MRCPI Helen Ling BScMed BMBS MSc David R. Williams PhD Constantinos Kallis PhD Janice L. Holton PhD FRCPath Tamas Revesz MD FRCPath David J. Burn MD FRCP Tarek Yousry Dr med Habil FRCR Andrew J. Lees MD FRCP Nick C. Fox PhD FRCP Hans R. Jäger MD FRCR 《Movement disorders》2012,27(14):1754-1762
Conventional magnetic resonance imaging (cMRI) is often used to aid the diagnosis of progressive supranuclear palsy (PSP) and multiple system atrophy (MSA), but its ability to predict the histopathological diagnosis has not been systematically studied. cMRI from 48 neuropathologically confirmed cases, including PSP (n = 22), MSA (n = 13), Parkinson's disease (PD) (n = 7), and corticobasal degeneration (n = 6), and controls (n = 9) were assessed blinded to clinical details and systematically rated for reported abnormalities. Clinical diagnosis and macroscopic postmortem findings were retrospectively assessed. Radiological assessment of MRI was correct in 16 of 22 (72.7%) PSP cases and 10 of 13 (76.9%) MSA cases with substantial interrater agreement (Cohen's kappa 0.708; P < .001); no PSP case was misclassified as MSA or vice versa. MRI was less sensitive but more specific than clinical diagnosis in PSP and both more sensitive and specific than clinical diagnosis in MSA. The “hummingbird” and “morning glory” signs were highly specific for PSP, and “the middle cerebellar peduncle sign” and “hot cross bun” for MSA, but sensitivity was lower (up to 68.4%) and characteristic findings may not be present even at autopsy. cMRI, clinical diagnosis, and macroscopic examination at postmortem have similar sensitivity and specificity in predicting a neuropathological diagnosis. We have validated specific radiological signs in pathologically confirmed PSP and MSA. However, the low sensitivity of these and macroscopic findings at autopsy suggest a need for imaging techniques sensitive to microstructural abnormalities without regional atrophy. © 2012 Movement Disorder Society 相似文献
9.
10.
Estela Trebicka Susan Jacob Waheed Pirzai Bryan P. Hurley Bobby J. Cherayil 《Clinical and Vaccine Immunology : CVI》2013,20(10):1491-1498
Recent observations from Africa have rekindled interest in the role of serum bactericidal antibodies in protecting against systemic infection with Salmonella enterica serovar Typhimurium. To determine whether the findings are applicable to other populations, we analyzed serum samples collected from healthy individuals in the United States. We found that all but 1 of the 49 adult samples tested had robust bactericidal activity against S. Typhimurium in a standard in vitro assay. The activity was dependent on complement and could be reproduced by immunoglobulin G (IgG) purified from the sera. The bactericidal activity was inhibited by competition with soluble lipopolysaccharide (LPS) from S. Typhimurium but not from Escherichia coli, consistent with recognition of a determinant in the O-antigen polysaccharide. Sera from healthy children aged 10 to 48 months also had bactericidal activity, although it was significantly less than in the adults, correlating with lower levels of LPS-specific IgM and IgG. The lone sample in our collection that lacked bactericidal activity was able to inhibit killing of S. Typhimurium by the other sera. The inhibition correlated with the presence of an LPS-specific IgM and was associated with decreased complement deposition on the bacterial surface. Our results indicate that healthy individuals can have circulating antibodies to LPS that either mediate or inhibit killing of S. Typhimurium. The findings contrast with the observations from Africa, which linked bactericidal activity to antibodies against an S. Typhimurium outer membrane protein and correlated the presence of inhibitory anti-LPS antibodies with human immunodeficiency virus infection. 相似文献