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91.
Biased immunoglobulin variable region gene expression by Ly-1 B cells due to clonal selection 总被引:11,自引:0,他引:11
C A Pennell T J Mercolino T A Grdina L W Arnold G Haughton S H Clarke 《European journal of immunology》1989,19(7):1289-1295
Most, if not all, autoantibodies specific for bromelain-treated mouse erythrocytes recognize the common membrane phospholipid, phosphatidyl choline (PtC). Anti-PtC antibodies are produced by 5%-15% of CD5+ Ly-1 B cells of normal unimmunized mice, but not by detectable numbers of conventional CD5- B cells. At 1 week of age PtC-specific B cells are undetectable but then increase dramatically over the next 3 to 4 weeks to reach adult numbers. We report here that PtC-specific Ly-1 B cells in B10.H-2aH-4bp/Wts mice predominantly express either of two heavy and kappa chain variable (V) region gene combinations. In addition, the sequence and length of DH genes are conserved among cells expressing the same V gene combination, and the V kappa-J kappa junctions of one group involve unusual splice sites. Preferential V gene rearrangement models are insufficient to explain the DH and V kappa-J kappa junctional sequences or the delayed appearance of this specificity, and so they cannot solely account for the high frequency of PtC-specific cells. These characteristics are more consistent with antigen selection. We therefore attribute the frequent use of the two V region gene combinations to selection for cells that express them and conclude that the expressed V gene repertoire of Ly-1 B cells in adult mice is influenced by antigen selection. Apparently, there is no selection for mutant anti-PtC antibodies of higher affinity during the formation of the Ly-1 B repertoire because the V region genes expressed by PtC-specific cells are unmutated. Our findings are consistent with an important, germ line-encoded function for the immunoglobulin products of these gene combinations. 相似文献
92.
A Z Arnold 《Postgraduate medicine》1987,81(4):283-287
Physicians have been reminded repeatedly of the many faces of bacterial endocarditis. In this case, Corynebacterium endocarditis presented as an occult malignancy and eluded diagnosis for six months. The coryneform isolates found in cultures are often considered to be contaminants because of their ubiquitous nature, sometimes causing a delay in diagnosis. Patients with culture-negative endocarditis or Corynebacterium "contamination" should be treated as having Corynebacterium endocarditis pending results of microbiologic isolation tests. 相似文献
93.
E A Brown I R Arnold P E Gower 《British medical journal (Clinical research ed.)》1986,292(6514):163-166
Twenty eight patients who had received haemodialysis for more than 10 years were reviewed to establish the incidence of joint problems. Only six patients had no joint symptoms, one had avascular necrosis, one had had recent septic arthritis, and four had hyperparathyroidism. The remaining 16 patients had no evidence of hyperparathyroidism yet had an arthropathy causing pain and stiffness in many joints, particularly the shoulders. Ten of these 16 patients had a recurrent carpal tunnel syndrome requiring repeated surgical decompressions, which resulted in only partial improvement. Of the eight patients who had received dialysis for more than 15 years, seven had this "dialysis arthropathy" and six had recurrent carpal tunnel syndrome. Dialysis arthropathy is a common and often severe and disabling complication of long term treatment with haemodialysis. The cause is not known, but amyloid was found in a synovial biopsy specimen from one patient. 相似文献
94.
Kenneth A. Kesler MD Malcolm B. Herring MD Michael P. Arnold MD Howard M. Park MD Sally Baughman MD John L. Glover MD 《Annals of vascular surgery》1986,1(1):60-65
A fibronectin substrate will significantly enhance the strength of endothelial cell attachment on grafts constructed of polyester elastomer (PE) and polytetrafluoroethylene (e-PTFE). This experiment was undertaken to determine the short-termin vivo stability of endothellum on these fibronectin coated surfaces. Eight mongrel dogs underwent bilateral carotid artery replacement with both graft materlals. All grafts were inoculated with 2,000 cells/mm2 using cultured autogenous venous endothelium labelled with Indium-111-oxine. The Indium-111 label in the grafts was measured immediately prior to implantation, after 1 hour ofin vivo perfusion, and at explantation after 24 hours. The percentage of inoculated cells attached to the grafts before perfusion was simillar for both materials, 93.3±3.0% versus 92.2±7.2%, for PE and e-PTFE respectively. All grafts were patent at one hour after implantation. PE grafts were found to have 93.8±3.9 % of the attached cells present at one hour while e-PTFE grafts had only 54.5 ± 10.8 % remaining, p<.001. After 24 hours, 5/8 (62.5%) e-PTFE grafts and 2/8 (25.0 %) PE grafts remained patent, p=.13. Of the patent grafts however, endothelial cell retention was still superior on the PE grafts with 78.0±0.6% of the attached cells remaining compared to only 24.5±6.1% on e-PTFE, p<.001. Occluded PE grafts had fewer cells remaining at 24 hours than patent ones, 78.0±0.6% versus 31.1±32.8%, respectively, p=.13. Histologically, patent PE grafts demonstrated nearly confluent endothelial monolayers while e-PTFE had patches of endothelial cells surrounded by, a platelet-fibrin carpet. We conclude that short-term patency appears to be determined by the extent of endothelial retention on PE but not e-PTFE. 相似文献
95.
OBSESSIVE–COMPULSIVE DISORDER (OCD) IS A COMMON and debilitating neuropsychiatric disorder. Although it is widely believed to have a genetic basis, no specific genetic factors have been conclusively identified as yet, leading researchers to look for environmental risk factors that may interact with an underlying genetic susceptibility in affected individuals. Recently, there has been increasing interest in a possible link between streptococcal infections and the development of OCD and tic disorders in children. It has been suggested that OCD in some susceptible individuals may be caused by an autoimmune response to streptococcal infections, that is, a similar biological mechanism to that associated with Sydenham's chorea. The term “pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections” (PANDAS) has been used to describe a subset of children with abrupt onset or exacerbations of OCD or tics, or both, following streptococcal infections. Affected children have relatively early symptom onset, characteristic comorbid symptoms and subtle neurological dysfunction. Neuroimaging studies reveal increased basal ganglia volumes, and the proposed cause involves the cross-reaction of streptococcal antibodies with basal ganglia tissue. Vulnerability to developing PANDAS probably involves genetic factors, and elevated levels of D8/17 antibodies may represent a marker of susceptibility to PANDAS. Prophylactic antibiotic treatments have thus far not been shown to be helpful in preventing symptom exacerbations. Intravenous immunoglobulin therapy may be an effective treatment in selected individuals. Further understanding of the role of streptococcal infections in childhood-onset OCD will be important in determining alternative and effective strategies for treatment, early identification and prevention of this common and debilitating psychiatric disorder. 相似文献
96.
Chan Stephen W. W. Chien C. W. Wong Arnold Y. L. Pang Marco Y. C. 《Quality of life research》2021,30(6):1779-1791
Quality of Life Research - To translate and cross-cultural validate the PROMIS Pediatric-25 Profile 2.0 (PROMIS-25) into traditional Chinese, and to investigate its psychometric properties in... 相似文献
97.
Iterative reconstruction algorithms 总被引:7,自引:0,他引:7
In this paper a survey of recent results on iterative reconstruction algorithms is given. These results, many of which have not yet appeared elsewhere, are applicable to a very general formulation of the reconstruction problem based on the series expansion approach. A set of optimization criteria and a number of iterative reconstruction algorithms are stated, together with theorems on the convergence of the algorithms to optimum images. The efficacy of the algorithms is compared to that of the convolution method. In particular, the falseness of the claim that ART and the backprojection method are the same is demonstrated. 相似文献
98.
Total parenteral nutrition during acute pancreatitis: Clinical experience with 156 Patients 总被引:3,自引:0,他引:3
Arnold P. Robin M.D. Rebecca Campbell R.D. Colathur K. Palani M.D. Katherine Liu M.D. Philip E. Donahue M.D. Lloyd M. Nyhus M.D. 《World journal of surgery》1990,14(5):572-579
Over a 3-year period, 156 of 815 patients admitted to a single institution with acute pancreatitis received total parenteral nutrition (TPN) for 2,572 patient days. Seventy had simple acute pancreatitis (group I) and 86 (group II) developed local complex disease (pseudocyst, abscess, or necrotic gland). In groups I and II, respectively, days without oral intake (NPO) were 13.6±1.5 (SEM) and 24.0±2.1 (p<0.005), hospital days were 19.8±1.7 and 35.8±3.2 (p<0.005), and duration of TPN was 10.9 ±1.0 and 21.0±2.3 days (p<0.005). Thirty-three patients in group I and 53 in group II required exogenous insulin. Alteration of standard formulas was necessary in 87 patients, but cessation of therapy was necessary in only one instance. Twenty catheters were removed for suspected sepsis with only 3 confirmed cases. Fat-based formulas were well tolerated in 15% of patients. During TPN, body weight rose from 95.0±2.4% to 97.4±4.3% of ideal in group I and remained at 90.5±1.8% in group II. Albumin rose from 3.36±0.10 to 3.50±0.08 g/dl in group I and from 3.01±0.07 to 3.35±0.07 g/dl in group II. The entire cohort differed from 10 randomly chosen patients who did not receive TPN in terms of days NPO (2.8±0.3) and hospital days (5.5±0.6). Variables associated with prolongation of hospital stay and time NPO were number of prognostic criteria, local complex disease, and underlying chronic pancreatitis only in select groups. We conclude that during acute pancreatitis, TPN can be administered safely but with careful monitoring and we recommend early aggressive therapy in the subgroups noted above and when underlying malnutrition exists. In the borderline patient, TPN may be administered by peripheral vein until the severity of disease is manifest.
Presented at the Société Internationale de Chirurgie in Toronto, Ontario, Canada, September, 1989. 相似文献
Resumen En el curso de un período de 3 años, 156 de 815 pacientes hospitalizados en una sola institución por pancreatitis aguda recibieron nutrición parenteral total (NPT) durante 2,572 paciente-días. Setenta presentaban pancreatitis aguda simple (grupo I) y 86 (grupo II) desarrollaron enfermedad local complicada (pseudoquiste, absceso, o necrosis de la glándula). Las siguientes fueron las características de los grupos I y II, respectivamente: días sin ingesta oral (NPO) 13.6±1.5 (SEM) y 24.0±2.1 (p<0.005), días de hospitalización: 19.8±1.7 y 35.8±3.2 (p<0.005), y duración de la NPT: 10.9±1.0 y 21.0 ±2.3 días (p<0.005). Trienta y tres pacientes en el grupo I y 53 en el grupo II requirieron insulina exógena. Se requirió alterar la fórmula estándar en 87 pacientes, pero sólo fue necesario cesar la terapia en un caso. Veinte catéteres fueron retirados por sospecha de sepsis, pero sólo en 3 se confirmó. Las fórmulas a base de grasa fueron bien toleradas en 15% de los pacientes. En el curso de la NPT el peso corporal ascendió de 95.0±2.4% a 97.4±4.3% del peso ideal en el grupo I y se mantuvo a un 90.5±1.8% en el grupo II. La albúmina ascendió de 3.36±0.10 a 3.50±0.8 g/dl en el grupo I y de 3.01±0.07 a 3.35±0.07 g/dl en el grupo II. Toda la cohorte se diferenció de un grupo de 10 pacientes escogidos al azar que no recibieron NPT en términos del número de días NPO (2.8±0.3) y de días de hospitalización (5.5±0.6). Las variables que aparecieron asociadas con prolongación de la hospitalización y el tiempo NPO fueron el número de criterios de pronóstico, la enfermedad complicada, y la presencia de pancreatitis crónica subyacente sólo en grupos seleccionados. Nuestra conclusión es que en el curso de la pancreatitis aguda, la NPT puede ser administrada con seguridad pero bajo monitoría cuidadosa, y recomendamos terapia agresiva precoz en los subgrupos anotados anteriormente y cuando exista mal nutrición concomitante. En el paciente limitrofe se puede administrar la NPT por vía periférica hasta cuando la gravedad de la enfermedad se haga manifiesta.
Résumé Pendant une période de 3 ans, 156 des 815 patients admis pour pancréatite aiguë ont reçu une alimentation parentérale totale (APT), soit en tout 2,572 jours patient. Soixante dix patients (groupe I) avaient une pancréatite simple et 86 (groupe II) avaient aussi une maladie locale complexe (pseudokyste, abcès ou nécrose du pancréas). La durée du jeûne était respectivement de 13.6±1.5 (ET) et de 24.0±2.1 (p<0.005), la durée moyenne de séjour était respectivement de 19.8±1.7 et de 35.8 ±3.2 (p<0.005) alors que la durée d'APT était respectivement de 10.9±1.0 et de 21.0±2.3 jours (p<0.005). Trente-trois patients dans le groupe I et 53 dans le groupe II avaient besoin d'insuline exogène. Un changement dans la formule standard a été nécessaire chez 87 patients mais l'APT n'a du être arrêté complètement que chez un patient seul. Vingt cathéters ont été enlevés avec suspicion de sepsis, confirmée cependant dans 3 cas seulement. Les compositions à base de lipides ont été bien tolérées chez 15% des patients. Pendant l'APT, le poids du corps s'est élevé de 95.0±2.4% à 97.4±4.3% du poids idéal chez les patients du groupe I et est resté à 90.5±1.8% chez ceux du groupe II. L'albumine s'est élevée de 3.36±0.10 à 3.50 ±0.08 g/dl dans le groupe I et de 3.01±0.07 à 3.35±0.07 g/dl dans le groupe II. La durée du jeûne (2.8±0.3) et la durée moyenne de séjour (5.5±0.6) de l'ensemble des patients différaient de ces mêmes données chez 10 autres patients choisis au hasard. Les facteurs associés avec un séjour hospitalier prolongé et sans alimentation orale étaient le nombre de critères pronostiques, l'existence de complications locales, et de pancréatite chronique sous-jacente chez certains patients. Nous concluons que pendant la pancréatite aiguë, l'APT peut être administrée sans danger sous contrôle permanent et nous conseillons un traitement agressif et précoce dans le sous groupe mentionné plus haut ou quand existe un état de nutrition déficient. Chez le patient limite, on peut se contenter d'APT par une veine périphérique tant que des signes de gravité ne se manifestent pas.
Presented at the Société Internationale de Chirurgie in Toronto, Ontario, Canada, September, 1989. 相似文献
99.
M. -G. Martinoli J. Q. Trojanowski M. L. Schmidt S. E. Arnold T. M. Fujiwara V. M. -Y. Lee H. Hurtig J. -P. Julien C. Clark 《Acta neuropathologica》1995,90(3):239-243
Apolipoprotein E (APOE) is a lipoprotein expressed in liver and brain as one of three isoforms (APOE 2, APOE 3 and APOE 4). Recent findings suggest that the presence of APOE 4 is associated with an increased risk for both familial Alzheimer's disease and late-onset Alzheimer's disease. We extended these observations by determining the frequency of APOE alleles in patients with pathologically confirmed Alzheimer's Disease (AD), Parkinson's disease (PD), diffuse Lewy Body disease (DLBD), AD with concomitant PD pathology, demented PD patients without or with concomitant AD pathology and in schizophrenics with a progressive dementia (SCHIZ+DEM). The APOE genotype was determined by restriction digestion of polymerase chain reaction-amplified DNA isolated from frozen brain samples. The frequency of the APOE 4 allele was highest among sporadic AD and DLBD patients (0.30 and 0.38, respectively) and lowest in the SCHIZ+DEM and non-demented PD patients (0.06 and 0.1, respectively). Thus, the APOE 4 allele is over-represented selectively in patients with dementias associated with plaques and tangles and/or cortical Lewy bodies, but not in demented schizophrenics or non-demented PD patients. 相似文献
100.
Arnold M Serpas D Case T Burns M DiPolito J Cummings E 《Journal of mental health administration》1995,22(1):85-93
The purpose of this investigation was to attempt to describe the health care needs of families providing in-home care to members with developmental disabilities as well as the characteristics and demographics of families providing in-home care. The survey included 761 families who participated in a federal demonstration project in rural southern Georgia. The results indicated that impoverished families need increased assistance to provide adequate medical and health care when providing in-home care to relatives experiencing developmental disabilities. Implications for administration of programs and development of policies are discussed. 相似文献