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Hein David W.; Flammang Thomas J.; Kirlin Ward G.; Trinidad Alma; Ogolla Fredrick 《Carcinogenesis》1987,8(12):1767-1774
A genetic polymorphism in S-acetyl coenzyme A (AcCoA)-dependentN-acetyltransferase has been associated with a differentialrisk for certain cancers in humans. In this study, several tissuesfrom the inbred Syrian hamster with a genetically defined AcCoA-dependentN-acetyltransferase polymorphism (homozygous rapid acetylator,Bio. 87.20; homozygous slow acetylator, Bio. 82.73/H; and heterozygousacetylator, Bio. 87.20 x Bio. 82.73/H F1), were investigatedfor the relationship of arylamine N-acetyltransferase to theAcCoA-dependent metabolic activation of carcinogenic N-hydroxy(N-OH)-arylamines to bind to DNA (O-acetyltransferase). Thelevels of both 2-aminofluorene (AF) N-acetyltransferase andN-OH-AF O-acetyltransferase activity reflected the N-acetylatorgenotype in liver, intestine, kidney and lung cytosols. A significantacetylator genedose response for AF N-acetyltransferaseand N-OH-AF O-acetyltransferase activities was observed in liverand lung cytosols. In contrast, acetylator genotype was notconsistently expressed for the AcCoA-dependent N-acetylationof 4-aminobiphenyl (ABP), nor for the AcCoA-dependent metabolicactivation of N-OH ABP and N-OH-3,2'-dimethyl-4-aminobiphenylin these me tissue cytosols. Two peaks of acetyltransferaseactivity were partially purified by ion exchange FPLC chromatographyfrom the hepatic cytosol of both the homozygous rapid and homozygousslow acetylator hamster. In contrast to unfractionated cytosol,the isozyme(s) eluting first clearly demonstrated levels ofAcCoA-dependent arylamine N-acetyltransferase and N-OH-arylamineO-acetyltransferase activities that were consistent with N-acetylatorgenotype (polymorphic) for all substrates tested. In contrast,the slower eluting isozyme(s) in each acetylator cytosol showedlevels of AcCoA-dependent N-and O-acetyltransferase activitiesthat did not vary with N-acetylator genotype (monomorphic).The AcCoA-dependent O-acetyltransferase activity of both themonomorphic and polymorphic peaks was paraoxon resistant. Thesestudies demonstrate acetylator genotype-dependent control ofAcCoA-dependent metabolic activation of N-OH-arylamines(O-acetylation)by polymorphic isozyme(s) similar to that for AcCoA-dependentN-acetylation of arylamines in the hamster. The polymorphicgenetic control of N-OH arylamine O-acetyltransferase may bean important risk factor for arylamine-induced cancer, in thosespecies and tissues expressing appreciable levels of O-acetyltransferaseactivity. 相似文献
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Dr. Joseph A. Kuhn MD Lawrence D. Wagman MD John A. Lorant MD Fredrick W. Grannis MD Mordecai Dunst MD William R. Dougherty MD Daniel I. Jacobs MD 《Annals of surgical oncology》1994,1(4):353-359
Background: A radical forequarter amputation with partial chest wall resection (one to four ribs) has been reported for benign and malignant
lesions involving the shoulder and chest wall region. Concerns about reconstruction and postoperative pulmonary function have
previously limited more extensive chest wall resections. The current report describes the first case in which a complete unilateral
anterior and posterior chest wall resection and pneumonectomy (hemithoracectomy) accompany a forequarter amputation. A novel
reconstructive technique used the full circumference of the forearm tissue with an intact ulna as a free osseomyocutaneous
flap.
Methods: In this case, a 21-year-old patient presented with an extensive recurrent desmoid tumor that involved the shoulder, brachial
plexus, subclavian vein, and chest wall from the lateral sternal border to the midportion of the scapula and down to the eighth
rib. The operative technique involved removal of the entire right hemithorax from the midline sternum to the transverse process
posteriorly, down to the ninth rib inferiorly. Due to the absence of a rigid hemithorax, the uninvolved ipsilateral lung was
also removed. The forearm flap was prepared before final separation of the specimen and division of the subclavian vessels.
Results: Postoperatively, the patient maintained excellent oxygenation without atelectasis or fever and was extubated on the 15th
postoperative day. As expected after pneumonectomy, significant decreases from preoperative to immediate postoperative values
were noted for the vital capacity (VC) (from 4.87 L to 1.29 L), forced 1-s expiratory volume (FEV1) (from 3.77 L to 1.02 L),
and inspiratory capacity (IC) (3.33 1 to 0.99 1). Rehabilitation included a specially designed external prosthesis to provide
cosmesis and prevent scoliosis. By the 15th postoperative week the patient had returned to normal social and physical activities,
with a gradual improvement in all respiratory parameters: VC 1.52 L, FEV1 1.29 L, IC 1.04 L. There has been no evidence of
tumor recurrence at 1 year.
Conclusions: This report provides evidence that a complete hemithoracectomy, pneumonectomy, and forequarter amputation can be safely performed
for selective tumors involving the shoulder region with extensive chest wall invasion. Reconstruction may be achieved with
an extended forearm osseomyocutaneous free flap with an excellent functional outcome.
Presented at the 46th Annual Cancer Symposium of The Society of Surgical Oncology, Los Angeles, California, March 18–21, 1993. 相似文献
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Datar RA Rueggeberg FA Caughman GB Wataha JC Lewis JB Schuster GS 《Journal of biomaterials science. Polymer edition》2005,16(10):1293-1302
The biological effects of camphorquinone (CQ), an initiator for light-polymerized resins, have been reported to relate to its ability to generate free radicals and cause radical-induced membrane damage via lipid peroxidation. However, the effects of CQ on lipids other than peroxidation may result in unfavorable tissue responses especially at concentrations that are not overtly toxic to cells. The purpose of the current study was to examine the effects of CQ on cell lipid metabolism at subtoxic concentrations, with or without visible light irradiation. HCP and THP-1 cells were exposed to CQ with or without light irradiation under clinically relevant conditions and lipid metabolism was analyzed using 14C-labeling and thin-layer chromatography. We found that CQ increased synthesis of neutral lipids, such as triglycerides, from 7 to nearly 15% of the total and diglycerides from 2% to about 3% of the total in HCP cells, while synthesis of phospholipids, such as sphingomyelin, was decreased by 1-1.5%. In THP-1 cells cholesterol synthesis increased more than 2-fold and cholesterol ester synthesis increased more than 5-fold. Light-activated CQ did not differ significantly in terms of its bioactivity compared to no-light conditions. We conclude that CQ significantly altered the metabolism of several important structural lipids in two cell types at sub-toxic concentrations that are clinically relevant. These changes in lipid metabolism may in turn affect membrane integrity and permeability and possibly lead to significant changes in cell responses. 相似文献
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Lodenyo H Rana F Mutuma GZ Kabanga JM Kuria JK Okoth FA 《African journal of health sciences》2005,12(1-2):49-54
Upper gastrointestinal complaints are common in Kenya. Though these have remained unchanged over the last 20 years, the pattern of upper gastrointestinal disease on endoscopic examination seems to be changing. There appears to be progressive increase in oesophagitis and cancer of the stomach. Peptic ulcer disease has remained stable while Cancer of the oesophagus is still common. The paper intends to report on endoscopic findings at the Centre for Clinical Research, Kenya Medical Research Institute (KEMRI) over the period October 1998 and May 2001. The sources of information are records made at the time of endoscopy and histology reports on biopsies taken. Seven hundred and sixty eight patients were endoscoped. The male to female ratio was 1.7:1 with mean age +/-SD of 40.8 +/-20.1 years and age range was 3 to 96 years. Majority of the patients had abnormal findings with gastritis being the most common ( 25.8%). It is concluded that gastritis is an important cause of morbidity in Kenya. Oesophagitis, mainly due to gastroesophageal reflux disease, seems to be on the increase. Gastric cancer is not as rare as previously thought and peptic ulcer disease is still common. 相似文献
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Infection of the reproductive tract and eggs with Salmonella enterica serovar pullorum in the chicken is associated with suppression of cellular immunity at sexual maturity 下载免费PDF全文
Wigley P Hulme SD Powers C Beal RK Berchieri A Smith A Barrow P 《Infection and immunity》2005,73(5):2986-2990
Salmonella enterica serovar Pullorum causes persistent infections in laying hens. Splenic macrophages are the main site of persistence. At sexual maturity, numbers of bacteria increase and spread to the reproductive tract, which may result in vertical transmission to eggs or chicks. In this study we demonstrate that both male and female chickens may develop a carrier state following infection but that the increases in bacterial numbers and spread to the reproductive tract are phenomena restricted to hens, indicating that such changes are likely to be related to the onset of egg laying. The immunological responses during the carrier state and through the onset of laying in hens were determined. These indicate that chickens produce both humoral and T-cell responses to infection, but at the onset of laying both the T-cell response to Salmonella and nonspecific responses to mitogenic stimulation fall sharply in both infected and noninfected birds. The fall in T-cell responsiveness coincided with the increase in numbers of Salmonella serovar Pullorum and its spread to the reproductive tract. Three weeks after the onset of egg laying, T-cell responsiveness began to increase and bacterial numbers declined. Specific antibody levels changed little at the onset of laying but increased following the rise in bacterial numbers in a manner reminiscent of a secondary antibody response to rechallenge. These findings indicate that a nonspecific suppression of cellular responses occurs at the onset of laying and plays a major role the ability of Salmonella serovar Pullorum to infect the reproductive tract, leading to transmission to eggs. The loss of T-cell activity at the point of laying also has implications for Salmonella enterica serovar Enteritidis infection and transmission to eggs, along with its control by vaccination offering a "window of opportunity" in which infection may occur. 相似文献
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