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41.
Matthew Freedman MD Dot Steller Hamid Jafroudi Seong Ki Mun 《Journal of digital imaging》1995,8(2):67-74
Quality control (QC) of storage phosphor devices is important in assuring that the image information entered into an Image management and communication (IMAC) system is sufficient for diagnosis. QC of storage phosphor digital radiography systems is complex because of the self-corrective nature of the image-processing software used in these machines. Currently, one must produce hard copy to perform adequate QC. Inspection of images with reject analysis and inspection of cassettes and imaging plates has helped us in our QC program. For those QC tests using control limits, the appropriate settings for these limits are unknown. Starting approximations are given. Recommended tests are described. 相似文献
42.
Nawawi HM Yazid TN Ismail NM Mohamad AR Nirwana SI Khalid BA 《The Malaysian journal of pathology》2001,23(2):79-88
The objectives of this study were to: (i) evaluate the diagnostic sensitivity and specificity of the biochemical bone markers: serum total alkaline phosphatase (TALP), bone specific alkaline phosphatase (BSALP) and urinary deoxypyridinoline (Dpyr) in postmenopausal osteoporosis, (ii) compare the bone turnover of postmenopausal osteoporotic patients without and with hormone replacement therapy (HRT) against controls and (iii) identify the correlation between these bone markers and bone mineral density (BMD). We examined 42 postmenopausal women with BMD proven osteoporosis and 35 control subjects. Serum TALP, BSALP and urinary Dpyr were measured. All three biochemical bone markers showed comparable moderate diagnostic sensitivity but Dpyr had the highest diagnostic specificity. There were significantly higher serum TALP, BSALP and urinary Dpyr levels in non-HRT treated patients compared to controls (p<0.005, <0.0001 and <0.005 respectively). There were no significant differences in the levels of all three bone markers between HRT treated patients and control subjects. There was no significant correlation between TALP, BSALP or Dpyr and BMD in both controls and patients. In conclusion, the biochemical bone markers are not useful in diagnosis of postmenopausal osteoporosis but may have a role in monitoring progress and response to treatment. HRT treatment reduces bone turnover of postmenopausal osteoporosis. 相似文献
43.
Pepe C Foley S Shannon J Lemiere C Olivenstein R Ernst P Ludwig MS Martin JG Hamid Q 《The Journal of allergy and clinical immunology》2005,116(3):544-549
BACKGROUND: Airway remodeling in asthma comprises a range of structural changes. Several studies have suggested an association between these changes and disease severity. The relationship between the extent of remodeling and lung function is not well defined. OBJECTIVE: We sought to contrast the structural changes in the airways of well-defined groups of subjects with severe and moderate asthma and to correlate the extent of remodeling with disease severity. METHODS: Endobronchial biopsy specimens were obtained from 15 subjects with severe and 13 subjects with moderate asthma. Epithelial integrity, cell-layer areas, subepithelial fibrosis, and the distance between epithelial and airway smooth muscle (ASM) layers were measured by means of image analysis. Collagen was identified by using Van Giesen stain, and ASM was defined by using smooth muscle alpha-actin immunostaining. Specific immunostains were performed for the evaluation of RANTES, IL-8, and eotaxin expression as markers of ASM phenotype. RESULTS: ASM area was greater in subjects with severe (0.24+/- 0.03 mm(2)) than in subjects with moderate (0.05+/- 0.01 mm(2)) asthma (P<.001). The distance between the epithelial and ASM layers was less in the severe group (0.12+/- 0.01 mm) than in the moderate group (0.24+/- 0.02, P<.001). A trend toward greater subepithelial fibrosis in subjects with severe asthma did not reach statistical significance. IL-8 and eotaxin expression, but not RANTES expression, were increased in the ASM of subjects with severe asthma compared with in subjects with moderate asthma. CONCLUSION: Smooth muscle alteration is the key structural change that distinguishes severe from moderate asthma, and phenotypic change in ASM might contribute to the difficulty in obtaining adequate control in some subjects with severe asthma. 相似文献
44.
The Cbl family of ubiquitin ligases: critical negative regulators of tyrosine kinase signaling in the immune system 总被引:9,自引:0,他引:9
The Cbl family of proteins are evolutionarily conserved negative regulators of activated tyrosine kinase-coupled receptors. Antigen receptors are prominent targets of negative regulation by the Cbl family members, Cbl and Cbl-b, which proteins function as ubiquitin ligases. Cbl and Cbl-b contain substrate recognition domains that interact specifically with activated protein tyrosine kinases of the Src and Syk/ZAP-70 families. Cbl-mediated ubiquitination of these kinases leads to their degradation, resulting in attenuation of receptor signals. Cbl may also control activation-induced monoubiquitination of antigen receptors, thus facilitating their delivery to lysosomes for subsequent degradation. Finally, the interactions of Cbl proteins with downstream targets of tyrosine kinases, such as PI-3-kinase and Vav, could provide an additional mechanism to attenuate receptor signaling. By targeting multiple components of antigen receptor signaling for degradation, the Cbl protein family provides a critical mechanism to ensure an appropriate immune response. The hyperresponsiveness of Cbl(-/-) and Cbl-b(-/-) lymphocytes and the autoimmune phenotype of Cbl-b(-/-) mice lend strong support for this proposal. The ability to control early receptor signals through regulated protein degradation provides a novel paradigm of immunoregulation. 相似文献
45.
Moallem HJ Taningo G Jiang CK Hirschhorn R Fikrig S 《Clinical immunology (Orlando, Fla.)》2002,105(1):75-80
Purine nucleoside phosphorylase (PNP) deficiency results in an autosomal recessive immunodeficiency disease characterized by initial involvement of cellular immunity and neurological manifestations with subsequent abnormalities of humoral immunity. The initial presentation and clinical course has varied widely in the relatively few published cases. The molecular basis has been reported in only 10 patients, precluding evaluation of phenotype-genotype relationships. We now report clinical, immunologic, and molecular findings in a new case of relatively early onset that emphasizes hypotonia and developmental delay as early manifestations. The patient carried two novel missense mutations (Gly56A1a and Val217Ile) on the same allele in apparent homozygosity. Expression of each of the mutant enzymes in vitro demonstrated that the Gly156A1a mutation abolished enzyme activity while the Val217Ile mutation was without obvious effect and is therefore a normal variant. Such "normal" polymorphisms might be associated with a variable response to the immunosuppressive PNP inhibitors currently in clinical trials. 相似文献
46.
Elaine Tierney Irena Bukelis Richard E Thompson Khalid Ahmed Alka Aneja Lisa Kratz Richard I Kelley 《American journal of medical genetics. Part B, Neuropsychiatric genetics》2006,(6):666-668
Although Smith-Lemli-Opitz Syndrome (SLOS), a genetic condition of impaired cholesterol biosynthesis, is associated with autism [Tierney et al., 2001; Am J Med Genet 98:191-200.], the incidence of SLOS and other sterol disorders among individuals with autism spectrum disorders (ASD) is unknown. This study investigated (1) the incidence of biochemically diagnosed SLOS in blood samples from a cohort of subjects with ASD from families in which more than one individual had ASD and (2) the type and incidence of other sterol disorders in the same group. Using gas chromatography/mass spectrometry, cholesterol, and its precursor sterols were quantified in 100 samples from subjects with ASD obtained from the Autism Genetic Resource Exchange (AGRE) specimen repository. Although no sample had sterol levels consistent with SLOS, 19 samples had total cholesterol levels lower than 100 mg/dl, which is below the 5th centile for children over age 2 years. These findings suggest that, in addition to SLOS, there may be other disorders of sterol metabolism or homeostasis associated with ASD. 相似文献
47.
Hauber HP Gotfried M Newman K Danda R Servi RJ Christodoulopoulos P Hamid Q 《The Journal of allergy and clinical immunology》2003,112(1):58-63
BACKGROUND: New hydrofluoroalkane (HFA) formulations of glucocorticoids have been shown to effectively control asthma. HFA glucocorticoids are deposited across all sizes of airways, including the small ones. However, it is not clear whether they can suppress peripheral airway inflammation. OBJECTIVE: We sought to determine whether HFA-flunisolide could suppress peripheral inflammation in asthma. METHODS: Twelve patients with mild to moderate asthma received HFA-flunisolide for 6 weeks. Transbronchial and endobronchial biopsy specimens were obtained before and after treatment, and spirometry was performed. Changes in inflammatory cells (eosinophils, neutrophils, lymphocytes, macrophages, basophils) and IL-5 and eotaxin were measured by using immunocytochemistry and in situ hybridization. RESULTS: Lung function significantly improved after treatment (P <.05). HFA-flunisolide significantly reduced eosinophils, IL-5, and eotaxin in both peripheral and central airways (P <.01). Neutrophils significantly increased after treatment in peripheral and central airways (P <.05). The numbers of lymphocytes remained unchanged. CONCLUSIONS: These results show that HFA-flunisolide effectively suppressed eosinophilic inflammation in peripheral and central airways. These changes were accompanied by improvement in lung function. 相似文献
48.
Elias JA Homer RJ Hamid Q Lee CG 《The Journal of allergy and clinical immunology》2005,116(3):497-500
Chitin is the second most abundant biopolymer in nature, where it protects crustaceans, parasites, fungi, and other pathogens from the adverse effects of their environments, hosts, or both. Because chitin does not exist in mammals, it had been assumed that the chitinases that degrade it are also restricted to lower life forms. However, chitinases and chitinase-like proteins have recently been noted in mice and human subjects. The prototypic chitinase, acidic mammalian chitinase, was also noted to be induced during T(H)2 inflammation through an IL-13-dependent mechanism. It was also shown to play an important role in the pathogenesis of T(H)2 inflammation and IL-13 effector pathway activation and demonstrated to be expressed in an exaggerated fashion in human asthmatic tissues. The finding that chitinases contribute to host anti-parasite responses and asthmatic T(H)2 inflammation support the concept that asthma might be a parasite-independent anti-parasite response. 相似文献
49.
Evidence for increased expression of eotaxin and monocyte chemotactic protein-4 in atopic dermatitis 总被引:7,自引:0,他引:7
Taha RA Minshall EM Leung DY Boguniewicz M Luster A Muro S Toda M Hamid QA 《The Journal of allergy and clinical immunology》2000,105(5):1002-1007
BACKGROUND: Atopic dermatitis (AD) is a chronic inflammatory skin disease associated with tissue eosinophilia and the activation of T lymphocytes. The novel eosinophil chemoattractants, eotaxin and monocyte chemotactic protein (MCP)-4, are up-regulated at sites of allergic inflammation, yet their contribution to the pathophysiologic mechanisms of AD remains to be determined. OBJECTIVE: We sought to investigate the expression of eotaxin and MCP-4 in acute and chronic lesions from patients with AD and to determine their relationship to the numbers of resident inflammatory cells. METHODS: With use of in situ hybridization, the expression of eotaxin and MCP-4 messenger RNA (mRNA) in skin biopsy specimens from patients with acute and chronic AD skin lesions was compared with that of uninvolved skin from these patients and skin from healthy volunteers. RESULTS: There was a constitutive expression of eotaxin and MCP-4 mRNA in skin biopsy specimens from healthy subjects. Positive signal for chemokine mRNA was observed both within the epidermis and inflammatory cells (macrophages, eosinophils, and T cells) of the subepidermis in AD skin lesions. Within the subepithelium acute and chronic skin lesions exhibited a significant increase in the numbers of eotaxin and MCP-4 mRNA-positive cells compared with uninvolved skin (P <.01), whereas the numbers of eotaxin and MCP-4 mRNA-positive cells were significantly higher in chronic AD compared with acute AD skin lesions (P <.005, P <.001, respectively). Correlations were observed between the expression of eotaxin and MCP-4 mRNA and the presence of eosinophils and macrophages, respectively, in AD lesions (r(2) = 0.84, r(2) = 0.94). CONCLUSION: There is an increased expression of eotaxin and MCP-4 in acute and chronic lesions, suggesting that these chemotactic factors play a major role in the pathophysiologic mechanisms of AD. 相似文献
50.
Bruno Amduri Khalid Berrada Bernard Boutevin Michel Mlas Roy D. Bowden 《Macromolecular chemistry and physics.》1993,194(11):3001-3014
The synthesis of novel telechelic monodispersed diols produced from the radical monoaddition of an excess of 10-undecenol with novel α, ω-dithiols, initiated by peroxides, is presented. The telechelic dithiols employed were prepared from nonconjugated dienes and a commercially available dithiol, or by esterification of adipic acid with 2-mercaptoethanol. From these dithiols, the diols were selectively obtained in high yields. Such α, ω-dihydroxylated compounds were characterized by both 1H and 13C NMR spectroscopy. The diol which exhibits the ester functions shows excellent solubility in common organic solvents contrarily to the other ones. The physical properties (Tg, Tm and decomposition temperatures) of these diols were compared and it is noted that the thermostability of these monodispersed telechelic diols is much better than those of the polydispersed commercially available ones such as poly(ethylene glycol)s or poly(tetramethylene glycol)s. 相似文献