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51.
We examined the ability of an immobilized antibody to salivary amylase (Clin Chem 1985;33:1283-8) to react with amylase in macroamylasemic sera. The antibody removed 50% (SD 23%) of the total amylase activity from 39 macroamylase sera, a percentage indistinguishable (P greater than 0.75) from the percentage removed from concurrently analyzed sera from healthy volunteers (49%, SD 11%). Electrophoretic analysis of 23 macroamylasemic sera revealed that the antibody removed only part of the macroamylase band(s) in 71% of the cases. We conclude that the mean isoenzyme composition of the macroamylase complexes is essentially identical to the mean isoenzyme distribution in normal sera (i.e., about half salivary and half pancreatic amylase). Further, the immobilized antibody can be used to distinguish most patients with macroamylasemia from those with acute pancreatitis, because sera from the latter contain an increased proportion (greater than 80%) of pancreatic amylase. 相似文献
52.
Choyke PL; Frank JA; Girton ME; Inscoe SW; Carvlin MJ; Black JL; Austin HA; Dwyer AJ 《Radiology》1989,170(3):713
53.
Jorge Jimenez MD Margarita Ochoa RN Maria Paz Soler RN Patricio Portales SW 《Contraception》1984,30(6):523-533
A long-term follow-up study compared development and health of 128 breast-fed children whose mothers had received depotmedroxyprogesterone acetate (depot-MPA) while lactating and 142 control children whose mothers had used mechanical contraceptives or no contraceptives or had undergone sterilization. The children, who were approximately 4-1/2 years old at follow-up, showed no ill effects on their growth and development and health status from exposure to depot-MPA. Depot-MPA-treated mothers lactated significantly longer than controls and also had greater parity than controls. These factors apparently contributed to a difference in weight at follow-up. Compared with the SempePedron standard, more of the depot-MPA group were underweight and more controls were overweight. 相似文献
54.
Roles of myofibroblasts in prostaglandin E2-stimulated intestinal epithelial proliferation and angiogenesis 总被引:5,自引:0,他引:5
Prostaglandins (PG) are produced throughout the gastrointestinal tract and are critical mediators for a complex array of physiologic and pathophysiologic processes in the intestine. Intestinal myofibroblasts, which express cyclooxygenase (COX) and generate PGE(2), play important roles in intestinal epithelial proliferation, differentiation, inflammation, and neoplasia through secreting growth factors and cytokines. Here, we show that PGE(2) activated human intestinal subepithelial myofibroblasts (18Co) through Gs protein-coupled E-prostanoid receptors and the cyclic AMP/protein kinase A pathway. 18Co cells and primary colonic myofibroblast isolates expressed a number of growth factors; several of them were dramatically regulated by PGE(2). An epidermal growth factor-like growth factor, amphiregulin (AR), which was not expressed by untreated cells, was strongly induced by PGE(2). Expression of vascular endothelial growth factor A (VEGFA) was rapidly increased by PGE(2) exposure. Hepatocyte growth factor (HGF) was elevated in PGE(2)-treated myofibroblasts at both mRNA and protein levels. Thus, PGE(2)-activated myofibroblasts promoted the proliferation and migration of intestinal epithelial cells, which were attenuated by neutralizing antibodies to AR and HGF, respectively. Moreover, in the presence of PGE(2), myofibroblasts strongly stimulated the migration and tubular formation of vascular endothelial cells. Neutralizing antibody to VEGFA inhibited the observed stimulation of migration. These results suggest that myofibroblast-generated growth factors are important mediators for PGE(2)-induced intestinal epithelial proliferation and angiogenesis, which play critical roles in intestinal homeostasis, inflammation, and neoplasia. 相似文献
55.
MA Rafiq M Ansar CR Marshall A Noor N Shaheen A Mowjoodi MA Khan G Ali M Amin‐ud‐Din L Feuk JB Vincent SW Scherer 《Clinical genetics》2010,78(5):478-483
Rafiq MA, Ansar M, Marshall CR, Noor A, Shaheen N, Mowjoodi A, Khan MA, Ali G, Amin‐ud‐Din M, Feuk L, Vincent JB, Scherer SW. Mapping of three novel loci for non‐syndromic autosomal recessive mental retardation (NS‐ARMR) in consanguineous families from Pakistan. To date, of 13 loci with linkage to non‐syndromic autosomal recessive mental retardation (NS‐ARMR), only six genes have been established with associated mutations. Here we present our study on NS‐ARMR among the Pakistani population, where people are traditionally bound to marry within the family or the wider clan. In an exceptional, far‐reaching genetic survey we have collected more than 50 consanguineous families exhibiting clinical symptoms/phenotypes of NS‐ARMR. In the first step, nine families (MR2‐9 and MR11) with multiple affected individuals were selected for molecular genetic studies. Two families (MR3, MR4) showed linkage to already know NS‐ARMR loci. Fifteen affected and 10 unaffected individuals from six (MR2, MR6, MR7, MR8, MR9 and MR11) families were genotyped by using Affymetrix 5.0 or 6.0 single‐nucleotide polymorphism (SNP) microarrays. SNP microarray data was visually inspected by dChip and genome‐wide homozygosity analysis was performed by HomozygosityMapper. Additional mapping was performed (to exclude false‐positive regions of homozygosity called by HomozygosityMapper and dChip) on all available affected and unaffected members in seven NS‐ARMR families, using microsatellite markers. In this manner we were able to map three novel loci in seven different families originating from different areas of Pakistan. Two families (MR2, MR5) showed linkage on chromosome 2p25.3‐p25.2. Three families (MR7, MR8, and MR9) that have been collected from the same village and belong to the same clan were mapped on chromosome 9q34.3. MR11 maps to a locus on 9p23‐p13.3. Analysis of MR6 showed two positive loci, on chromosome 1q23.2‐q23.3 and 8q24.21‐q24.23. Genotyping in additional family members has so far narrowed, but not excluded the 1q locus. In summary, through this study we have identified three new loci for NS‐ARMR, namely MRT14, 15 and 16. 相似文献
56.
57.
58.
Erin O. Rice Theodore E. Mifflin Sameer Sakallah Robert E. Lee Carol A. Sansieri John A. Barranger 《Clinical genetics》1996,49(3):111-118
This report summarizes the results on 39 patients with Gaucher disease who have been genotyped, evaluated, and/or followed at this center. Mutation analysis for 4 common mutations; N370S, L444P, 84gg and IVS2 (+1), was performed for all patients. Mutation analysis identified both mutant alleles in 69% and at least one mutant allele in 90% of all chromosomes. This study group of 39 patients included 32 type 1, four type 2 and three type 3 patients. We include the details of the clinical course of two patients with Gaucher disease treated with enzyme replacement therapy (ERT). One patient with chronic neuronopathic Gaucher disease has been treated with enzyme replacement therapy (ERT) at a dose of 60 U/kg every 2 weeks since 2.5 years of age and has shown no progression of neurologic involvement. A second patient with non-neuronopathic Gaucher disease has demonstrated an unusually delayed response to ERT. No clinical response was noted following 17 months of treatment at 60 U/kg every 2 weeks. Only after the dose was increased to 60 U/kg every week was a clinical response evident. Response to treatment at 15 U/kg every 2 weeks was variable in the four type 1 patients treated at the lower dose. In two of these patients with identical genotypes, one patient demonstrated a positive clinical response to low dose treatment while the other patient did not. 相似文献
59.
Immunohistochemical study of myofibroblasts in normal colonic mucosa,hyperplastic polyps,and adenomatous colorectal polyps 总被引:10,自引:0,他引:10
Adegboyega PA Mifflin RC DiMari JF Saada JI Powell DW 《Archives of pathology & laboratory medicine》2002,126(7):829-836
CONTEXT: Myofibroblasts are distinct cells with characteristics of both smooth muscle cells and fibroblasts. Through their ability to secrete cytokines, chemokines, prostaglandins, growth factors, and matrix components, they are thought to play critical roles in inflammation, growth, repair, and neoplasia. OBJECTIVE: The goal of this study was to identify the distinct cell populations of the lamina propria of normal colon and colorectal polyps. DESIGN: We studied the expression of alpha-smooth muscle actin (alphaSMA), smooth muscle myosin (SMM), desmin, vimentin, and c-kit by intestinal mesenchymal (stromal) cells in the normal colonic mucosa (n = 5), as well as in hyperplastic polyps (n = 5), sporadic colorectal adenomas (n = 47), and adenomas from patients with familial polyposis (n = 36). RESULTS: In the normal colonic mucosa, the pericryptal stromal cells were alphaSMA+, SMM+, desmin-, and vimentin+, defining them as myofibroblasts. In contrast, cells of the muscularis mucosae were alphaSMA+, SMM+, desmin+, and vimentin-, defining them as smooth muscle cells. alpha-Smooth muscle actin also highlighted direct connections between the muscularis mucosae and the pericryptal myofibroblasts, and vimentin immunostaining showed a network of connections between the alphaSMA+ pericryptal myofibroblasts and the alphaSMA- fibroblasts in the interstitium. In all hyperplastic polyps and adenomatous polyps, the interstitial stromal cells (fibroblasts) now also express alphaSMA and form a syncytium of alphaSMA+ networklike connections throughout the lamina propria. Stromal cells of sporadic adenomas demonstrated the same immunohistochemical staining characteristics displayed by adenomas from patients with familial polyposis and by hyperplastic polyps. Conclusions.-These findings indicate that in normal colon, alphaSMA- fibroblasts are the predominant cell type in the lamina propria. However, the pericryptal (subepithelial) stromal cells are a distinct cell type (alphaSMA+ myofibroblast) that is immunophenotypically different from muscularis mucosae smooth muscle cells and are connected to the interstitial, nonpericryptal fibroblasts with which they exist as a network throughout the lamina propria of the normal colon. Furthermore, in both hyperplastic and neoplastic polyps, there are changes in nonpericryptal fibroblasts from vimentin+, alphaSMA-, and SMM- to vimentin+, alphaSMA+, and SMM+; thus, the interstitial fibroblasts are replaced by myofibroblasts. The factors that cause these changes and the origin of the myofibroblasts need to be determined to clarify the biology of colorectal tumorigenesis. 相似文献
60.
Intracellular recordings from hypoglossal motoneurons in the brainstem of cats are described, along with postsynaptic potentials evoked by superior laryngeal, vagal and carotid sinus nerve stimulation. The study concentrates on hypoglossal motoneurons with respiratory-related discharge, which can be categorized into inspiratory, inspiratory/early-expiratory and expiratory patterns. Seven cells were labelled with horseradish peroxidase, their location and morphology are described. Stimulation of laryngeal receptors by balloon inflation or by water injection into the larynx, or mimicked by electrical stimulation of the superior laryngeal nerve results in enhanced postinspiratory activity in those cells (inspiratory/early-expiratory, expiratory) already receiving postinspiratory excitation; or actually produces a wave of postinspiratory depolarization in cells (inspiratory) previously quiescent during that period. It is concluded that the firing pattern of the respiratory-modulated hypoglossal motoneurons is unlikely to be static but depends on other factors, one of these being the level of ongoing, or previous laryngeal receptor stimulation. 相似文献