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91.
Background
In the field of bariatric surgery, research on symptoms of adult attention deficit hyperactivity disorder (ADHD) and their interrelationships with other psychological risk factors such as depression and anxiety is scarce. The symptoms of adult ADHD seem to be common in the obese population, but they are rarely investigated before bariatric surgery. ADHD-related symptoms such as impulsivity have at the same time been identified as potential risk factors for less successful weight loss among bariatric surgery patients. The aims of the current study were to screen for symptoms of adult ADHD and to investigate their relationships with other psychological risk factors.Methods
Candidates for bariatric surgery (N?=?187) were anonymously screened for symptoms of anxiety, depression, and adult ADHD, in addition to disordered eating patterns, by means of questionnaires. The relations between these symptoms were investigated.Results
In the current sample, 10% of patients screened positively for adult ADHD, and the symptoms of adult ADHD were significantly correlated with those of anxiety, depression, and disordered eating.Conclusions
The results show that adult ADHD is more common in this clinical group than in the general population (4%) and that adult ADHD is associated with disordered eating patterns, depression, and anxiety. Further prospective research, using multivariate analysis, is needed to investigate whether the symptoms of adult ADHD, and their interaction with anxiety, depression, or disordered eating, may possibly constitute a risk factor in terms of difficulties in adhering to the post-surgery regime and its potential unfavorable outcome. 相似文献92.
93.
High-molecular-weight kininogen is exclusively membrane bound on endothelial cells to influence activation of vascular endothelium 总被引:3,自引:1,他引:3
An important biologic function of high-molecular-weight kininogen (HK) is to deliver bradykinin (BK) to its cellular receptors. Internalization and degradation of HK may provide a mechanism by which endothelial cells modulate the production of BK and control its activities. Therefore, we investigated the binding and subsequent distribution of biotinylated-HK (biotin-HK) associated with human umbilical vein endothelial cells (HUVEC). HUVEC bound 3 to 4 times more HK and with greater avidity at 1 to 3 hours at 37 degrees C than at 4 degrees C (Bmax = 1.0 +/- 0.02 x 10(7) molecules/cell, kd = 7 +/- 3 nmol/L v Bmax = 2.6 +/- 0.2 x 10(6) molecules/cell, kd = 46 +/- 8 nmol/L). However, there was no evidence that the difference was caused by internalization of HK at the higher temperature. First, the same amount of biotin-HK was associated with nonpermeabilized and permeabilized HUVEC using buffers containing 20 to 50 mumol/L zinc ion in the absence or presence of 2 mmol/L calcium ion. Second, binding of biotin-HK to HUVEC was approximately 92% reversible at 1 hour when the cells were maintained at both 37 degrees C and 4 degrees C. Third, neither chloroquine nor primaquine altered the amount of biotin-HK bound to HUVEC. Fourth, biotin-HK bound to HUVEC was almost completely removed by pronase. Fifth, the nonpermeable dye, crystal violet, almost completely quenched the fluorescence signal emitted by HUVEC-associated fluorescein isothiocyanate (FITC) HK. Finally, the localization of HUVEC-bound FITC-HK was restricted to the membrane as shown by laser scanning confocal microscopy. The expression of HK binding sites had an absolute requirement for metabolic energy, but was not dependent on new protein synthesis. Membrane-bound HK contributed to the anticoagulant nature of endothelial cells by blocking human alpha-thrombin binding and its resultant induction of prostacyclin formation. These studies indicate that HK is not internalized by HUVEC, but remains primarily on cell surfaces to be accessible for BK liberation and to modulate the binding and actions of alpha-thrombin. 相似文献
94.
Role of light chain variable region in myeloma with light chain deposition disease: evidence from an experimental model 总被引:4,自引:2,他引:4
Khamlichi AA; Rocca A; Touchard G; Aucouturier P; Preud'homme JL; Cogne M 《Blood》1995,86(10):3655-3659
Light chain deposition disease (LCDD) results from a propensity of some human monoclonal L chains to form tissue deposits. We designed an experimental model for in vivo expression of human kappa L chain sequences in mice and compared a somatically mutated LCDD chain with a closely related control kappa chain, both encoded by the unique V kappa IV gene. Mice secreting the LCDD chain but not those producing the control chain showed deposits with a distribution similar to that observed in patients. These data show that discrete changes in V region sequences can play a major role in tissue deposition of human L chains. 相似文献
95.
Background There is evidence for increased risk of thrombosis in patients with β-thalassemia intermedia and β-thalassemia major. The
present study investigated the prevalence of thromboembolic risk factors of prothrombin G20210A, factor V Leiden G1691A and
methylentetrahydrofolate reductase (MTHFR) C677T, as well as the hematological and clinical profiles in β-thalassemia major
and intermedia patients from Western Iran. Methods Patients consisted of 158 β-thalassemia patients, 151 β-thalassemia major and 7 β-thalassemia intermedia patients, including
82 males and 76 females aged 13.6 ± 6.3 years. The control group were 180 healthy blood donors and school students, consisting
of 103 males and 77 females aged 16.8 ± 2.1. Genotyping was done by PCR-RFLP using Mnl I, Hind III and Hinf I for factor V
Leiden and prothrombin G20210A and MTHFR, respectively. Results The prevalence of prothrombin G20210A variant in patients and healthy individuals were 1.3 and 3.3%, respectively. Factor
V Leiden G1691A was insignificantly higher in β-thalassemia patients (prevalence 5.7% and allele frequency 3.2%) compared
to healthy individuals (2.8%). This mutation was found in eight β-thalassemia major (5.3%) and one β-thalassemia intermedia
(14.3%) patients. The prevalence of MTHFR C677T polymorphism was slightly higher in patients (50%) compared to healthy individuals
(48.3%). Around 71% of β-thalassemia intermedia and 38.4% of β-thalassemia major patients had undergone splenectomy. In β-thalassemia
major patients, 5.3% had insulin dependent diabetes mellitus (IDDM) and 6.6% had HCV antibodies. All patients with IDDM were
splenectomized and in one of them the prothrombin G20210A variant was found. Two patients, a 7-year-old boy with β-thalassemia
intermedia receiving regularly blood transfusion and a β-thalassemia major patient (a 22-year-old splenectomized female),
were found to be homozygous for MTHFR 677TT and heterozygous for factor V Leiden G1691A. Double heterozygosity for factor
V Leiden G1691A and MTHFR C677T and also homozygous factor V Leiden 1691AA were found in two β-thalassemia major patients.
No thromboembolic event has been recorded in the files of patients. Conclusions The results of present study establish the prevalence of biological risk factors of thrombosis in β-thalassemia patients
from Western Iran. It seems that thrombophilic mutations may not be associated with thrombotic events in thalassemic patients,
which needs to be confirmed by the study of larger
sample sizes. 相似文献
96.
The Ig heavy chain (IgH) gene was used as a marker to investigate clonal succession and the origin of the neoplastic cell in multiple myeloma. The polymerase chain reaction (PCR) was used to amplify a section of the rearranged IgH gene at diagnosis and at progression in 21 patients who had exhibited a plateau phase. A monoclonal PCR product was seen for 16 of the patients and the product present at progression was of the same molecular weight as that at diagnosis. This finding suggests that the IgH rearrangement present at diagnosis and progression was the same. This was confirmed by sequencing the IgH gene in 10 patients. The IgH genes were found to be hypermutated at diagnosis, but no further hypermutation occurred during the course of the disease. The results provide evidence that the neoplastic cell in myeloma may originate as a memory B cell, plasmablast, or plasma cell, and suggest that progression beyond the plateau phase is not caused by clonal succession. 相似文献
97.
Heterogeneity of breakpoints of 11q23 rearrangements in hematologic malignancies identified with fluorescence in situ hybridization 总被引:3,自引:0,他引:3
Kobayashi H; Espinosa R d; Thirman MJ; Gill HJ; Fernald AA; Diaz MO; Le Beau MM; Rowley JD 《Blood》1993,82(2):547-551
Twenty-four patients whose cells contained a variety of 11q23 rearrangements, including translocations, insertions, and an inversion, were studied using fluorescence in situ hybridization with cosmid, phage, and plasmid probes mapped to 11q22-24. In 17 patients, the breakpoints of the common 11q23 translocations involving chromosomes 4, 6, 9, and 19 as well as some uncommon translocations involving 3q23, 17q25, 10p11, and an insertion 10;11 were all located in the breakpoint cluster region of the MLL gene, regardless of age, phenotype of disease, or involvement of a third chromosome. The breakpoints in 11q23 in the other 7 patients with a t(7;11)(p15;q23), inv(11)(p11q23), t(4;11)(q23;q23), der(5)t(5;11)(q13;q23), ins(10;11)(p11;q23q24), t(11;14)(q23;q11), or t(11;18;11) (p15;q21;q23) were located either centromeric to CD3D or telomeric to THY1. Thus, although most 11q23 rearrangements, involve the same breakpoint cluster region of MLL, there is heterogeneity in the breakpoint in some of the rare rearrangements. 相似文献
98.
This paper studies a design problem concerning installation locations for a number of structural magneto‐rheological (MR) dampers. The mechanical characteristic of each MR damper is functional dependent to an input current, which is regulated by a Fuzzy Logic controller. It is demanded that the chosen arrangement of dampers should change the dynamic response of the structure to meet certain constraints expressed in terms of minimization of an objective function. For this purpose, an improved version of Ant Colony Optimization algorithm is presented. The modified algorithm also utilizes additional heuristic data derivable from a pre‐analysis of the structure in the optimization procedure. Further improvements regarding convergence speed of search algorithm are proposed as well, provided numerical examples study the functionality of the algorithm in different cases. With an acceptable probability from a structural designer's point of view, the proposed method finds qualified solutions during a reasonable number of search iterations. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
99.
Digital and conventional chest images: observer performance with Film Digital Radiography System 总被引:5,自引:0,他引:5
The Film Digital Radiography System (FilmDRS) is a device with a laser optical film digitizer, 2,000 X 2,000 X 12-bit memory, and a 1,000-line video display. To evaluate the adequacy of this device for general radiography of the chest, four readers independently analyzed both radiographs and the corresponding video display of the digitized chest images of 150 patients, consisting of 100 images of abnormalities and 50 normal images. The overall results indicate equal sensitivity for the two systems. The FilmDRS, with interactive windowing, proved superior in the detection of hilar and mediastinal disease. X-ray film was superior in allowing detection of hyperlucent states. There was equivalent sensitivity for other disease categories. Superior specificity was achieved with conventional radiographs. 相似文献
100.