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991.
Exogenous advanced glycosylation end products induce diabetes-like vascular dysfunction in normal rats: a factor in diabetic retinopathy 总被引:2,自引:0,他引:2
Xun Xu Zhiping Li Dawei Luo Yufeng Huang Jianfeng Zhu Xiaojue Wang Honghui Hu C. Patrick 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2003,241(1):56-62
BACKGROUND. Diabetic retinopathy has been shown to be directly associated with the degree and duration of hyperglycemia, and advanced glycosylation end products (AGEs) have been implicated in this pathological process. The purpose of the experiments reported here was to study the effect of AGE deposition on retinal vascular damage which leads to diabetic retinopathy. METHODS. Intravenous injection of exogenous AGEs was used to treat wild-type non-diabetic Sprague-Dawley rats. One of the two retinal slides from each animal was treated using immunohistochemical staining to label retinal vascular AGE deposition, the other H&E staining for counting of capillary pericytes. The results were compared with the findings in untreated wild-type and diabetic controls and in rats treated with unmodified rat serum albumin (RSA). RESULTS. After 2 weeks of continuous treatment, AGEs were identified in the retinal vascular tissue of the AGE-RSA-injected group. The average number of retinal capillary pericytes per 10x100 microscope power field was 4.313+/-0.34 (mean +/- SD) in the AGE-RSA-injected group, compared with 5.798+/-0.481 in the control group ( P<0.01). CONCLUSION. These experiments demonstrate that AGEs, independent of other metabolic factors, can induce vascular change resembling that of diabetic retinopathy. 相似文献
992.
Contact lens fitting may be required following keratoplasty for either optical or thera‐peutic reasons. Optical indications for contact lens fitting include the correction of irregular astigmatism, high regular astigmatism, anisometropia and secondary aniseikonia, as well as simple ametropia, where the patient desires to wear contact lenses in preference to spectacles. Therapeutic lenses are not routinely fitted following kerate plasty, although this management is advised in certain cases, such as when there are protruding sutures or epithelial healing is impaired. Designing a contact lens for a patient who has undergone keratoplasty will require the practitioner to carefully assess all the relevant features of the corneal graft. In this regard, there are many factors that need to be considered including the diameter of the graft zone, the topographical relationship between the host cornea and donor cornea, the corneal (graft) toricity and the location of the graft. Special designs, such as reverse geometry lenses, or more complex contact lens modalities, such as piggyback contact lens systems, may be required to achieve success in fitting. 相似文献
993.
Lia Assumpcao John L. Cameron Christopher L. Wolfgang Barish Edil Michael A. Choti Joseph M. Herman Jean-Francois Geschwind Kelvin Hong Christos Georgiades Richard D. Schulick Timothy M. Pawlik 《Journal of gastrointestinal surgery》2008,12(11):1915-1923
Background
No data on incidence, management, or natural history of chyle leaks following pancreatic resection have been published. We
sought to identify possible risk factors associated with chyle leaks following pancreatic resection, as well as determine
the natural history of this rare complication.
Methods
Between 1993 and 2008, 3,532 patients underwent pancreatic resection at a single institution. Data on demographics, operative
details, primary tumor status, and chyle leak were collected. To identify risk factors associated with chyle leak, a matched
3:1 paired analysis was performed.
Results
Of 3,532 patients undergoing pancreatic resection, 47 (1.3%) developed a chyle leak (n = 34, contained chyle leak versus n = 13, diffuse chylous ascites). Chyle leak was identified at median 5 days following surgery. Median drain triglyceride levels
were 592 ng/dl. After matching on tumor size, disease etiology, and resection type, the number of lymph nodes harvested and
history of concomitant vascular resection predicted higher risk of chyle leak (both P < 0.05). Total parenteral nutrition (TPN) was required in more patients with chylous ascites (92.3%) than those with chyle
leaks (44.1%) (P = 0.003). The median time to resolution was shorter for contained chyle leaks (13 days) versus chylous ascites (36 days)
(P < 0.001). Patients with chylous ascites tended to have shorter overall survival (3-year, 18.8%) versus patients with no chyle
leak (3-year, 46.9%) (P = 0.12). In contrast, patients with a contained chyle leak had a similar survival as patients with no chyle leak (3-year,
53.4% versus 46.9%, respectively) (P = 0.32).
Conclusion
Chyle leak was a rare (1.3%) complication following pancreatic resection that was associated with number of lymph nodes harvested
and concomitant vascular resection. In general, chyle leaks were successfully managed with TPN with no adverse impact on outcome.
Patients with chylous ascites, however, had a more protracted clinical course and tended to have a worse long-term survival.
Presented at the Society for Surgery of the Alimentary Tract, 49th Annual Meeting, San Diego, CA, May 18th, 2008
Support: Dr. Pawlik is supported by Grant Number 1KL2RR025006-01 from the National Center for Research Resources (NCRR), a
component of the National Institutes of Health (NIH), and NIH Roadmap for Medical Research. The contents of this publication
are solely the responsibility of the authors and do not necessarily represent the official view of NCRR or NIH. 相似文献
994.
Gardenia C. G. Militão Daniel P. Bezerra Claudia Pessoa Manoel Odorico de Moraes Flavio A. F. da Ponte Mary Anne S. Lima Edilberto R. Silveira Letícia V. Costa-Lotufo 《Journal of natural medicines》2007,61(2):196-199
The purpose of this study was to investigate the antiproliferative activity of 2,3,9-trimethoxypterocarpan, a known pterocarpan
with cytotoxic activity against many tumor cell lines, in a panel of four leukemia cell lines (HL-60, Molt-4, Jurkat, and
K562) and on human peripheral blood mononuclear cells (PBMC). The pterocarpan showed IC50 ranging from 0.1 to 0.5 μg/ml at leukemic cells after 72 h of incubation, with K562 being the most resistant cell line. This
compound seemed to be selective to tumor cell lines, since at a concentration of 10 μg/ml after 72 h, it only reduced 19%
of viable peripheral mononuclear cells. 相似文献
995.
A high molecular weight arabinogalactan protein (AGP) from the pressed juice of Echinacea purpurea, known to exhibit immunomodulatory properties in vitro, was characterized. Alkaline hydrolysis was carried out, leading to
degradation of the protein core and to carbohydrate moieties linked to the amino acid responsible for binding. Gel permeation
chromatography of these AG subunits gave one peak with a molecular weight of 30 × 103 Da. Hydroxyproline (42.9% w/w) was detected as the dominant amino acid after alkaline hydrolysis and was thus identified as
the major amino acid responsible for the binding between the protein and the AG subunits via an O-glycosidic linkage. Large
amounts of glutamine/glutamic acid (24.5% w/w) and asparagine/aspartic acid (17.3% w/w) were also found. Polyclonal antibodies
raised against the intact AGP were shown to bind to the AG subunits too, indicating that the epitopes responsible for such
interactions are localized in the polysaccharide moiety of the AGP. 相似文献
996.
997.
Marco Frattini Enrico Vaienti Giovanni Soncini Francesco Pogliacomi 《Musculoskeletal surgery》2009,93(3):109-114
Tibial plateau fractures are complex injuries which, if not adequately treated, can lead to invalidating sequelae. They constitute
on average about 1% of all fractures, and up to 8% in patients over 65 years, and can be caused by both high- and low-energy
trauma. Unlike in younger subjects, treatment of tibial plateau fractures in the elderly is not univocal and depends on the
patient’s functional needs, bone quality and systemic comorbidities. In this retrospective study, 49 patients with a mean
age of 72 years, who underwent surgical treatment of a tibial plateau fracture, were assessed by the Rasmussen’s clinical
and radiological grading systems. Clinical and radiographic outcomes were satisfactory in 75.5 and 59.1% of cases, respectively.
Data were also analyzed, in terms of fracture type, age and gender, to detect any statistically significant correlation between
these parameters and clinical and radiographic outcomes. 相似文献
998.
Alberto J Espay Danielle M Andrade Richard A Wennberg Anthony E Lang 《Epileptic Disord》2005,7(3):227-230
Angelman syndrome is a neurogenetic disorder resulting in refractory epilepsy and profound psychomotor retardation in its most prevalent form, caused by deletion of maternal chromosome 15q11-13. We report the case of a 29-year-old, mentally retarded man with unusual electroencephalographic changes during periods of atypical absence status epilepticus, a previously unreported manifestation of the usually milder, drug-responsive epilepsy associated with Angelman syndrome due to the UBE3A mutation.[Published with video sequences]. 相似文献
999.
1000.
Sayime Aydin Bulent Ertugrul Berna Gultekin Guliz Uyar Erkin Kir 《BMC infectious diseases》2007,7(1):87