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Scott R. Ross Steven H. Putnam Scott R. Millis Kenneth M. Adams Rebecca A. Krukowski 《The Clinical neuropsychologist》2013,27(4):798-815
This study examined the capacity of the Seashore Rhythm Test (SRT) and the Speech-Sounds Perception Test (SSPT) to detect insufficient effort in a clinical sample. Forty-six participants with financially compensable mild head injury who obtained scores indicative of insufficient effort on multiple measures were compared to 49 participants with brain injury who were not involved in litigation. Receiver operating characteristic (ROC) curve analysis indicated that both the SRT (AUC = .84) and SSPT (AUC = .80) were significant (p < .001) predictors of insufficient effort. Maximizing sensitivity and specificity, the optimal cutoff scores were 8 errors on the SRT and 10 errors on the SSPT. Combining both variables into a logistic regression function increased the diagnostic efficiency. 相似文献
84.
Co-cultures of endothelial cells (EC) and mesenchymal stem cells (MSC) in three-dimensional (3D) protein hydrogels can be
used to recapitulate aspects of vasculogenesis in vitro. MSC provide paracrine signals that stimulate EC to form vessel-like
structures, which mature as the MSC transition to the role of mural cells. In this study, vessel-like network formation was
studied using 3D collagen/fibrin (COL/FIB) matrices seeded with embedded EC and MSC and cultured for 7 days. The EC:MSC ratio
was varied from 5:1, 3:2, 1:1, 2:3 and 1:5. The matrix composition was varied at COL/FIB compositions of 100/0 (pure COL),
60/40, 50/50, 40/60 and 0/100 (pure FIB). Vasculogenesis was markedly decreased in the highest EC:MSC ratio, relative to the
other cell ratios. Network formation increased with increasing fibrin content in composite materials, although the 40/60 COL/FIB
and pure fibrin materials exhibited the same degree of vasculogenesis. EC and MSC were co-localized in vessel-like structures
after 7 days and total cell number increased by approximately 70%. Mechanical property measurements showed an inverse correlation
between matrix stiffness and network formation. The effect of matrix stiffness was further investigated using gels made with
varying total protein content and by crosslinking the matrix using the dialdehyde glyoxal. This systematic series of studies
demonstrates that matrix composition regulates vasculogenesis in 3D protein hydrogels, and further suggests that this effect
may be caused by matrix mechanical properties. These findings have relevance to the study of neovessel formation and the development
of strategies to promote vascularization in transplanted tissues. 相似文献
85.
Assa'ad AH Putnam PE Collins MH Akers RM Jameson SC Kirby CL Buckmeier BK Bullock JZ Collier AR Konikoff MR Noel RJ Guajardo JR Rothenberg ME 《The Journal of allergy and clinical immunology》2007,119(3):731-738
BACKGROUND: Eosinophilic esophagitis (EE) is a gastrointestinal disorder that is increasingly diagnosed in pediatric patients. OBJECTIVE: We aimed to define, in pediatric patients with EE, their demographic and atopic characteristics, the histopathology of all segments of the gastrointestinal tract, and the effect of therapeutic interventions on the natural history. METHODS: We conducted a retrospective analysis of a database of pediatric patients with EE followed over a period of 8 years. RESULTS: In 89 pediatric patients with EE, male sex (78.6%), white race (94.4%), young age at diagnosis, mean +/- SD, 6.2 +/- 4.8 years, and atopy with sensitization to environmental and food allergens in 79% and 75%, respectively, were prevalent. Patients had EE of the proximal and distal esophagus, and 77% had in addition either mucosal eosinophilia or noneosinophilic histopathology in the stomach, duodenum, and colon. EE was chronic, with a duration of mean +/- SD, 0.91 +/- 0.84 years, until first resolution, and was recurrent; of 66% of the patients who had resolution, 79% later relapsed. CONCLUSION: Eosinophilic esophagitis in the pediatric population is a chronic and relapsing condition, associated with atopy and sometimes with subsequent histopathology in segments of the gastrointestinal tract other than the esophagus. CLINICAL IMPLICATIONS: Physicians evaluating pediatric patients with chronic gastrointestinal symptoms should consider the diagnosis of EE, particularly in young white male patients with atopy. Once diagnosed and treated, the physicians should follow the patients over a period of several years because the course of the disease is protracted, other gastrointestinal segments may be affected, and relapses are common. 相似文献
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Genetic variants of human serum albumin in Italy: point mutants and a carboxyl-terminal variant. 总被引:1,自引:1,他引:1 下载免费PDF全文
J Madison M Galliano S Watkins L Minchiotti F Porta A Rossi F W Putnam 《Proceedings of the National Academy of Sciences of the United States of America》1994,91(14):6476-6480
Of the > 50 different genetic variants of human serum albumin (alloalbumins) that have been characterized by amino acid or DNA sequence analysis, almost half have been identified in Italy through a long-term electrophoretic survey of serum. Previously we have reported structural studies of 11 Italian alloalbumins with point mutations, 2 different carboxyl-terminal variants, and 1 case of analbuminemia in an Italian family. This article describes confirmation by DNA sequencing of mutations previously inferred from protein sequencing of 4 of the above alloalbumins; it also reports the mutations identified by protein and DNA sequence analysis of 4 other Italian alloalbumins not previously recorded: albumin Larino, His3-->Tyr; Tradate-2 (protein sequencing only), Lys225-->Gln; Caserta, Lys276-->Asn; and Bazzano, a carboxyl-terminal variant. The first 3 have point mutations that produce a single amino acid substitution, but a nucleotide deletion causes a frameshift and an altered and truncated carboxyl-terminal sequence in albumin Bazzano. In these 4 instances the expression of the alloalbumin is variable, ranging from 10% to 70% of the total albumiN, in contrast to the usual 50% each for the normal and mutant albumin. The distribution of point mutations in the albumin gene is nonrandom; most of the 47 reported point substitutions involve charged amino acid residues on the surface of the molecule that are not concerned with ligand-binding sites. 相似文献
89.
Kobayashi H; Montgomery KT; Bohlander SK; Adra CN; Lim BL; Kucherlapati RS; Donis-Keller H; Holt MS; Le Beau MM; Rowley JD 《Blood》1994,84(10):3473-3482
Translocations and deletions of the short arm of chromosome 12 [t(12p) and del(12p)] are common recurring abnormalities in a broad spectrum of hematologic malignant diseases. We studied 20 patients and one cell line whose cells contained 12p13 translocations and/or 12p deletions using fluorescence in situ hybridization (FISH) with phage, plasmid, and cosmid probes that we previously mapped and ordered on 12p12-13. FISH analysis showed that the 12p13 translocation breakpoints were clustered between two cosmids, D12S133 and D12S142, in 11 of 12 patients and in one cell line. FISH analysis of 11 patients with deletions demonstrated that the deletions were interstitial rather than terminal and that the distal part of 12p12, including the GDI-D4 gene and D12S54 marker, was deleted in all 11 patients. Moreover, FISH analysis showed that cells from 3 of these patients contained both a del(12p) and a 12p13 translocation and that the affected regions of these rearrangements appeared to overlap. We identified three yeast artificial chromosome (YAC) clones that span all the 12p13 translocation breakpoints mapped between D12S133 and D12S142. They have inserts of human DNA between 1.39 and 1.67 Mb. Because the region between D12S133 and D12S142 also represents the telomeric border of the smallest commonly deleted region of 12p, we also studied patients with a del(12p) using these YACs. The smallest YAC, 964c10, was deleted in 8 of 9 patients studied. In the other patient, the YAC labeled the del(12p) chromosome more weakly than the normal chromosome 12, suggesting that a part of the YAC was deleted. Thus, most 12p13 translocation breakpoints were clustered within the sequences contained in the 1.39 Mb YAC and this YAC appears to include the telomeric border of the smallest commonly deleted region. Whether the same gene is involved in both the translocations and deletions is presently unknown. 相似文献
90.
Amino acid sequence of human plasma alpha 1B-glycoprotein: homology to the immunoglobulin supergene family. 总被引:4,自引:6,他引:4 下载免费PDF全文
N Ishioka N Takahashi F W Putnam 《Proceedings of the National Academy of Sciences of the United States of America》1986,83(8):2363-2367
The complete amino acid sequence has been determined for alpha 1B-glycoprotein (alpha 1B), a protein of unknown function present in human plasma. This protein (Mr approximately equal to 63,000) consists of a single polypeptide chain N-linked to four glucosamine oligosaccharides. The polypeptide has five intrachain disulfide bonds and contains 474 amino acid residues. Analysis of the amino acid sequence by several computer programs shows that alpha 1B exhibits internal duplication and consists of five repeating structural domains, each containing about 95 amino acids and one disulfide bond. alpha 1B has a unique amino acid sequence. However, several domains of alpha 1B, especially the third, show statistically significant homology to variable regions of certain immunoglobulin light and heavy chains. alpha 1B also exhibits sequence similarity to other members of the immunoglobulin supergene family such as the receptor for transepithelial transport of IgA and IgM and the secretory component of human IgA. Because of its internal duplication and its sequence homology to immunoglobulin-like proteins, alpha 1B appears to have evolved from an ancestral gene similar to that of the immunoglobulin supergene family. 相似文献