Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 36
Filtrar
1.
Handchir Mikrochir Plast Chir ; 47(6): 359-64, 2015 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-26562009

RESUMO

OBJECTIVE: The aim of this study was to determine whether the extirpation of lymphatic vessels induces lymphatic transport disturbances in the donor limb of patients following the harvest of lymph vessel grafts. PATIENTS, MATERIAL AND METHODS: A total of 19 consecutive patients (15 females, 4 males; mean age 51.5 years, range 21.8-72.3) were examined by lymphoscintigraphy before and after surgery. The patients had previously been diagnosed with upper or lower limb lymphoedema in accordance with the criteria of the International Society of Lymphology, and autologous lymph vessel transplantation had been intended for treatment. Since only patients with normal scintigraphic tests at the harvesting site were considered for treatment, all consecutive patients (n=19) had normal scintigraphic tests of the donor limb prior to surgery. In order to quantify the visual scintigraphic findings, a well established numeric transport index (TI) was used, which combined 5 visual parameters of transport kinetics. To that end, the following visually assessed criteria were evaluated: temporal and spatial kinetics, radiopharmaceutical distribution pattern, time to appearance of inguinal lymph nodes, qualitative visualisation of lymph nodes and lymph vessels. RESULTS: All patients underwent a preoperative scintigraphic baseline study and a postoperative scintigraphic follow-up after autologous lymphatic vessel grafting. The mean time period from the baseline study to the date of microsurgical lymph vessel transplantation was 3.5 months (median 2.5 months). The scintigraphic follow-up was performed 48.6 months (median 57.8 months) following transplantation. In all patients the postoperative TI was very close to the TI calculated in the preoperative baseline scintigraphy, and all TIs were within the normal range (TI<10). The absolute value of deviation of pre- vs. post-operative transport indices was calculated to be 0.2 on average (maximum 0.4). CONCLUSIONS: The results show that microsurgical transfer of lymph vessel grafts is possible without compromising lymphatic drainage of the donor limb if safety precautions are taken into account.


Assuntos
Extremidades/cirurgia , Vasos Linfáticos/transplante , Linfedema/diagnóstico por imagem , Linfedema/cirurgia , Linfocintigrafia , Microcirurgia/métodos , Complicações Pós-Operatórias/diagnóstico por imagem , Complicações Pós-Operatórias/etiologia , Coleta de Tecidos e Órgãos/efeitos adversos , Coleta de Tecidos e Órgãos/métodos , Adulto , Idoso , Extremidades/diagnóstico por imagem , Feminino , Seguimentos , Humanos , Vasos Linfáticos/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Adulto Jovem
2.
Clin Nephrol ; 73(1): 64-7, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20040354

RESUMO

Acute renal failure developed in an elderly woman with a rapidly progressive illness characterized by nuchal rigidity, limb spasm, repetitive grunting vocalizations without intelligible speech, and risus sardonicus. Eventually she developed characteristic findings of increased tone in her masseter muscles (trismus) and rigid upper and lower extremities, consistent with generalized tetanus. Increasing serum creatinine was temporally associated with rising creatine phosphokinase (CPK) and striking elevations of plasma myoglobin. The patient had marked lability of blood pressure and pulse. She improved briefly after tetanus toxoid and broad-spectrum antibiotics, but died of heart failure after 9 days of hospitalization. A necrotic pelvic tumor was believed to be the source of infection. Tetanus is a preventable disease, which has not been eradicated, even in Western populations. Full-blown tetanus has a high fatality rate, and should be considered in the differential diagnosis of acute renal failure in the setting of rising CPK and continued release of muscle myoglobin.


Assuntos
Injúria Renal Aguda/etiologia , Rabdomiólise/etiologia , Tétano/complicações , Acidentes por Quedas , Injúria Renal Aguda/sangue , Idoso de 80 Anos ou mais , Creatina Quinase/sangue , Creatinina/sangue , Progressão da Doença , Evolução Fatal , Feminino , Humanos , Mioglobina/sangue , Rabdomiólise/sangue , Tétano/sangue , Fatores de Tempo
3.
Arch Biochem Biophys ; 409(2): 274-86, 2003 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-12504894

RESUMO

Accumulating evidence suggests that the pathophysiology of diabetes is analogous to chronic inflammatory states. Circulating levels of inflammatory cytokines such as IL-6 and tumor necrosis factor alpha (TNFalpha) are increased in both type 1 and type 2 diabetes. TNFalpha plays an important role in the pathogenesis of insulin resistance in type 2 diabetes. However, the reason for this increase remains unclear. Levels of the dicarbonyl methylglyoxal (MGO) are elevated in diabetic plasma and MGO-modified bovine serum albumin (MGO-BSA) can trigger cellular uptake of TNF. Therefore we tested the hypothesis that MGO-modified proteins may cause TNFalpha secretion in macrophage-like RAW 264.7 cells. Treatment of cells with MGO-BSA induced TNFalpha release in a dose-dependent manner. MGO-modified ribonuclease A and chicken egg ovalbumin had similar effects. Cotreatment of cells with antioxidant reagent N-acetylcysteine (NAC) inhibited MGO-BSA-induced TNFalpha secretion. MGO-BSA stimulated the simultaneous activation of p44/42 and p38 mitogen-activated protein kinase. PD98059, a selective MEK inhibitor, inhibited MGO-BSA-induced TNFalpha release as well as ERK phosphorylation. Pretreatment of cells with NAC also resulted in inhibition of MGO-BSA-induced ERK phosphorylation. MGO-BSA induced dose-dependent NFkappaB activation as shown by electrophoresis mobility shift assay. The MGO-BSA-induced NFkappaB activation was prevented in the presence of PD98059, NAC, and parthenolide, a selective inhibitor of NFkappaB. Furthermore, the NFkappaB inhibitor parthenolide suppressed MGO-BSA-induced TNFalpha secretion. Confocal microscopy using dichlorofluorescein to demonstrate intracellular reactive oxygen species (ROS) showed that MGO-BSA produced more ROS compared with native BSA. MGO-BSA could also stimulate protein kinase C (PKC) translocation to the cell membrane, considered a key signaling pathway in diabetes. However, there was no evidence that PKC was involved in TNFalpha release based on inhibition by calphostin C and staurosporine. Our findings suggest that the presence of chronically elevated levels of MGO-modified bovine serum albumin may contribute to elevated levels of TNFalpha in diabetes.


Assuntos
Macrófagos/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/metabolismo , Aldeído Pirúvico/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Soroalbumina Bovina/farmacologia , Fator de Necrose Tumoral alfa/metabolismo , Animais , Bovinos , Relação Dose-Resposta a Droga , Ativação Enzimática , MAP Quinase Quinase Quinase 3 , MAP Quinase Quinase Quinases/metabolismo , Camundongos , Proteínas Quinases Ativadas por Mitógeno/efeitos dos fármacos , NF-kappa B/antagonistas & inibidores , Proteína Quinase C/efeitos dos fármacos , Proteína Quinase C/metabolismo , Espécies Reativas de Oxigênio/antagonistas & inibidores , Células Tumorais Cultivadas , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Proteínas Quinases p38 Ativadas por Mitógeno
4.
Adv Perit Dial ; 17: 93-7, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11510306

RESUMO

Abdominal catastrophe, defined as peritonitis from a visceral source, occurs in a significant number of patients treated by peritoneal dialysis. Peritonitis due to visceral injury is difficult to manage and is associated with high morbidity and mortality. Surgical intervention for both diagnosis and repair is definitive. However, no preventive strategy has been identified to date. The experience at University Hospitals of Cleveland and the published experiences of many other centers demonstrate that the risk of this complication has not changed in parallel with the many other improvements in the technique and outcome of peritoneal dialysis. We propose an approach to improve the understanding and outcome of this devastating complication. First, classification of peritonitis by source, not by organism, may lead to a more focused response to each episode of peritonitis. Second, the importance of antibiotic prophylaxis should be re-assessed in defined clinical settings that have a high likelihood of progressing to abdominal catastrophe. Third, optimal antibiotic regimens need to be devised and applied when visceral injury is highly suspected as a cause of peritonitis. Finally, the results of surgical interventions must be carefully studied.


Assuntos
Diálise Peritoneal/efeitos adversos , Peritonite/etiologia , Humanos , Peritonite/classificação , Peritonite/diagnóstico , Peritonite/microbiologia , Estudos Retrospectivos , Vísceras/lesões
5.
Diabetes Obes Metab ; 3(4): 230-9, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11520302

RESUMO

AIMS: Advanced glycation end products (AGE), which form from the non-enzymatic reaction of proteins and sugars, have been implicated in the pathogenesis of diabetic nephropathy. Recently, a compound [N-phenacylthiazolium bromide (PTB)] has been described which cleaves alpha,beta-dicarbonyl compounds. In the present study we used diabetic C57BL/6 mice to determine if PTB altered renal AGE levels and reduced diabetic glomerulosclerosis. METHODS: Mice with stable hyperglycaemia induced by streptozotocin were given daily subcutaneous injections of either PTB (10 microg/g) or saline for 12 weeks. Renal-collagen bound AGE and urinary AGE-peptides were measured by ELISA using an anti-AGE-RNase antibody. Renal collagen-released Nepsilon(carboxymethyl)lysine (CML) and pentosidine were determined by high pressure liquid chromatography (HPLC). Glomerular lesions (volume and mesangial/total surface area) were evaluated by computer-assisted image analysis. We determined urinary protein/creatinine ratio as a functional parameter. AGE localization was examined by immunohistochemistry using the anti-AGE-RNase antibody. RESULTS: Renal collagen-bound AGE were decreased and urinary AGE excretion was increased in PTB-treated diabetic mice. However, collagen-released CML and pentosidine were similar in both groups. Glomerular histology and morphometric analysis revealed also no differences between PTB-and saline-treated diabetic mice. The urinary protein/creatinine ratio was unaffected by PTB-treatment. AGE staining by anti-AGE-RNase antibody was present in Bowman's capsules, glomerular basement membranes and cortical tubules. It was decreased in all structures in PTB-treated diabetic mice. CONCLUSION: In summary, PTB decreased renal AGE accumulation but did not ameliorate glomerular lesions or proteinuria. Thus, cleavage of AGE by PTB is not sufficient to prevent development of diabetic nephropathy in C57BL/6 mice.


Assuntos
Arginina/análogos & derivados , Diabetes Mellitus Experimental/fisiopatologia , Nefropatias Diabéticas/fisiopatologia , Produtos Finais de Glicação Avançada/metabolismo , Rim/fisiopatologia , Lisina/análogos & derivados , Tiazóis/farmacologia , Animais , Arginina/farmacologia , Colágeno/metabolismo , Diabetes Mellitus Experimental/urina , Nefropatias Diabéticas/patologia , Nefropatias Diabéticas/urina , Feminino , Mesângio Glomerular/efeitos dos fármacos , Mesângio Glomerular/patologia , Produtos Finais de Glicação Avançada/urina , Rim/efeitos dos fármacos , Rim/patologia , Glomérulos Renais/efeitos dos fármacos , Glomérulos Renais/patologia , Lisina/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Proteinúria
6.
Am J Kidney Dis ; 37(5): 970-80, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11325679

RESUMO

The pathological role of oxidative stress in patients treated by hemodialysis has gained increasing recognition in recent years. Because complications related to vascular access are a major source of morbidity, immunohistochemical evidence of oxidative stress and activation of growth factors were examined in native arteriovenous (AV) fistulae (n = 11) and expanded polytetrafluoroethylene (ePTFE) grafts (n = 15) recovered from hemodialysis patients at the time of surgical revision or resection. To show the presence of oxidative stress in tissues, three markers were chosen: N(epsilon)(carboxymethyl)lysine, a structurally identified advanced glycation end product; 4-hydroxy-2,3-nonenol, a lipid peroxidation product; and redox-active transition metals bound to proteins, a source of Fenton chemistry-generated free radicals. Markers of cell growth and proliferation were endothelin-1 (ET-1), a potent mitogenic peptide implicated in the formation of intimal hyperplasia; transforming growth factor-beta (TGF-beta), a stimulus to vascular cell growth and matrix production; and platelet-derived growth factor (PDGF), a mediator of intimal hyperplasia. All specimens studied showed significant intimal hyperplasia. In general, the neointima close to the vascular lumen of the AV fistula and the pseudointima close to the lumen of the ePTFE graft were positive for oxidative stress markers. At sites of injury, especially in the presence of histological evidence of inflammation and healing, expression of oxidative markers was particularly intense. Prominent staining of PDGF was shown at sites of anastomotic hyperplasia and in neovasculature. TGF-beta was associated with proliferation or repair in both AV fistulae and ePTFE grafts. ET-1 staining was most intense in the neointima and pseudointima. This study showed histochemical colocalization of markers of oxidative stress with growth factors known to contribute to intimal hyperplasia.


Assuntos
Anastomose Arteriovenosa/metabolismo , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Substâncias de Crescimento/metabolismo , Falência Renal Crônica/metabolismo , Estresse Oxidativo/fisiologia , Diálise Renal/efeitos adversos , Adulto , Idoso , Fístula Arteriovenosa/complicações , Fístula Arteriovenosa/patologia , Biomarcadores/análise , Constrição Patológica/etiologia , Endotelina-1/análise , Feminino , Humanos , Hiperplasia/complicações , Hiperplasia/patologia , Ferro/análise , Falência Renal Crônica/terapia , Peroxidação de Lipídeos , Lisina/análogos & derivados , Masculino , Pessoa de Meia-Idade , Oxirredução , Fator de Crescimento Derivado de Plaquetas/análise , Politetrafluoretileno , Fator de Crescimento Transformador beta/análise , Túnica Íntima/patologia , Grau de Desobstrução Vascular
8.
Adv Perit Dial ; 16: 134-7, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11045278

RESUMO

In 1996, we raised our peritoneal dialysis (PD) dose to meet new DOQI adequacy targets. Concurrently, we noted an increase in the frequency of K+ levels below 3.5 mEq/L. A continuous quality improvement (CQI) project was initiated to quantify the impact of increasing dialysis dose on the prevalence of hypokalemia in our unit. Measurements of serum K+, blood urea nitrogen (BUN), creatinine, residual renal function, and the number and type of clinical interventions required to maintain eukalemia were abstracted from the charts of 62 patients enrolled in our program for more than 6 months and having more than two adequacy data points. In the seven consecutive 6-month periods from January 1996 to June 1999, dialysis dose progressively increased while median serum K+ decreased, and the percentage of patients requiring either diet counselling or K+ supplementation rose from 9% to 42%. We conclude that the increased clearance of K+ that occurs with increasing dialysis dose may lead to significant hypokalemia in a large proportion of PD patients dialyzed to DOQI adequacy targets. Maintenance of eukalemia in this population often requires increased K+ intake and or oral supplementation. Further studies are needed to ascertain whether the prevalence of hypokalemia is sufficient to warrant routine addition of K+ to PD dialysis solutions.


Assuntos
Hipopotassemia/etiologia , Diálise Peritoneal/efeitos adversos , Creatinina/metabolismo , Humanos , Diálise Peritoneal/métodos , Potássio/administração & dosagem , Potássio/sangue , Estudos Retrospectivos , Ureia/metabolismo
9.
Kidney Int ; 57(6): 2571-85, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10844627

RESUMO

BACKGROUND: Advanced glycation end products (AGEs) accumulate on tissue and plasma proteins in patients with renal failure far in excess of normal aging or diabetes. The aim of these studies was to elucidate the nature of the precursors and the pathways that lead to an accelerated formation of two structurally identified AGEs [pentosidine and Nepsilon(carboxymethyl)lysine (CML)] in the uremic milieu. METHODS: Serum levels of the glycoxidation products, pentosidine and CML, were quantitated by high-performance liquid chromatography in uremic patients treated by dialysis. The formation of early glycation products (as furosine) and late glycoxidation products was modeled in uremic serum and in spent peritoneal dialysate. RESULTS: Clinical factors that affect circulating levels of AGEs included dialysis clearance and dialyzer membrane pore size, but not the presence or absence of diabetes. Both pentosidine and CML form at an accelerated rate in serum from uremic patients. Chelating agents most effectively slow the formation in vitro. In uremic fluids, the primary mechanism of formation of pentosidine is through the Amadori pathway. The primary mechanism of formation of CML is through metal-chelated autoxidation of reducing sugars generating reactive carbonyl precursors. In uremic serum, the presence of an unidentified reactive low molecular weight precursor accelerates the formation of pentosidine. CONCLUSIONS: The formation of the two glycoxidation products, pentosidine and CML, proceeds by different pathways and is enhanced by different precursors in the uremic milieu. The formation of both AGEs is markedly enhanced by metal-catalyzed reactions, evidence for the presence of increased metal-ion mediated oxidant stress in uremia.


Assuntos
Produtos Finais de Glicação Avançada/biossíntese , Falência Renal Crônica/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Arginina/análogos & derivados , Arginina/sangue , Inibidores Enzimáticos/farmacologia , Feminino , Glucose/metabolismo , Produtos Finais de Glicação Avançada/sangue , Guanidinas/farmacologia , Humanos , Falência Renal Crônica/sangue , Falência Renal Crônica/terapia , Lisina/análogos & derivados , Lisina/sangue , Reação de Maillard , Masculino , Pessoa de Meia-Idade , Oxirredução , Diálise Peritoneal , Diálise Renal
10.
Am J Physiol Renal Physiol ; 278(4): F676-83, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10751230

RESUMO

Increased activation of specific protein kinase C (PKC) isoforms and increased nonenzymatic glycation of intracellular and extracellular proteins [the accumulation of advanced glycation end products (AGEs)] are major mechanistic pathways implicated in the pathogenesis of diabetic complications. Blocking PKC-beta(II) has been shown to decrease albuminuria in animal models of diabetes. To demonstrate a direct relationship between AGEs and the induction and translocation of PKC-beta(II), studies were carried out in rat neonatal mesangial cells, known to express PKC-beta(II) in association with rapid proliferation in post-natal development. Oxidative stress was studied by using the fluorescent probe dichlorfluorescein diacetate. Translocation of PKC-beta(II) was demonstrated by using immunofluorescence and Western blotting of fractionated mesangial cells. Induction of intracellular oxidative stress, increase in intracellular calcium, and cytosol to membrane PKC-beta(II) translocation (with no change in PKC-alpha) were demonstrated after exposure to AGE-rich proteins. These data support the hypothesis that AGEs cause mesangial oxidative stress and alterations in PKC-beta(II), changes that may ultimately contribute to phenotypic abnormalities associated with diabetic nephropathy.


Assuntos
Animais Recém-Nascidos/metabolismo , Mesângio Glomerular/metabolismo , Produtos Finais de Glicação Avançada/farmacologia , Isoenzimas/metabolismo , Estresse Oxidativo , Proteína Quinase C/metabolismo , Animais , Transporte Biológico/efeitos dos fármacos , Divisão Celular/fisiologia , Células Cultivadas , Ativação Enzimática/fisiologia , Mesângio Glomerular/citologia , Mesângio Glomerular/efeitos dos fármacos , Membranas Intracelulares/metabolismo , Proteína Quinase C beta , Ratos , Ratos Sprague-Dawley
11.
Kidney Int ; 57(1): 92-104, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10620191

RESUMO

UNLABELLED: Studies of renal injury III: Lipid-induced nephropathy in type II diabetes. BACKGROUND: Nephrotoxicity from elevated circulating lipids occurs in experimental and clinical situations. We tested the hypothesis that lipid-induced nephropathy causes advanced renal failure in rats with type II diabetes and dyslipidemia. METHODS: First generation (F1) hybrid rats derived from the spontaneous hypertensive heart failure rat (SHHF/Gmi-fa) and the LA/NIH-corpulent rat (LA/N-fa) were studied for 41 weeks while being on specific diets. Group 1 (14 rats) ingested 11.5% protein, 47.9% fat, and 40.6% carbohydrate. Group 2 (8 rats) ingested 26.9% protein, 16.7% animal fat, and 56.4% carbohydrate, and group 3 (20 rats) ingested 20.2% protein, 40.4% soy and coconut oil, and 39.4% carbohydrate. RESULTS: Hyperglycemia was more severe in rat groups 1 and 2 than in group 3. In contrast, circulating cholesterol and hydroperoxide levels were highest in group 3, intermediate in group 2, and lowest in group 1. Group 3 had severe renal failure secondary to glomerulosclerosis and tubulointerstitial disease, with striking deposition of the lipid peroxidation stress biomarker 4-hydroxynonenal in glomeruli and renal microvessels. Moreover, in group 3, increased arterial wall thickness also connoted vascular injury. In contrast, the glycoxidation stress biomarkers pentosidine and carboxymethyl-lysine were preferentially localized to renal tubules of hyperglycemic rats in groups 1 and 2 and did not segregate with the most severe renal injury. Glomerular and interstitial fibrosis was accompanied by proportional increases in renal transforming growth factor-beta1 levels, which were threefold higher in the hypercholesterolemic rats of group 3 than in the hyperglycemic rats of group 1. CONCLUSIONS: Acquisition of non-nodular glomerular sclerosis and tubulointerstitial disease is dependent on lipoxidation stress in rats with type II diabetes. On the other hand, in the absence of hypercholesterolemia, prolonged glycoxidation stress does not appear to be uniquely nephrotoxic.


Assuntos
Nefropatias Diabéticas/fisiopatologia , Hipercolesterolemia/complicações , Animais , LDL-Colesterol/sangue , Nefropatias Diabéticas/complicações , Nefropatias Diabéticas/metabolismo , Ensaio de Imunoadsorção Enzimática , Feminino , Produtos Finais de Glicação Avançada/metabolismo , Imuno-Histoquímica , Testes de Função Renal , Glomérulos Renais/metabolismo , Túbulos Renais Proximais/metabolismo , Peroxidação de Lipídeos , Masculino , Obesidade/complicações , Obesidade/metabolismo , Ratos , Renina/metabolismo , Fator de Crescimento Transformador beta/metabolismo
12.
Perit Dial Int ; 20 Suppl 5: S33-8, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11229610

RESUMO

Advanced glycosylation end-products (AGEs) are associated with diabetic complications and peritoneal damage after long-term peritoneal dialysis (PD) with high glucose dialysis solutions. Glucose degradation products (GDPs) derived during heat sterilization of high glucose dialysis solutions are thought to accelerate AGE formation. A new technique of separating glucose from electrolytes has yielded markedly lower GDP levels and permitted the use of dialysis solutions containing the physiologic buffer bicarbonate. Formation of AGEs in vitro with this new solution is significantly lower compared with formation of AGEs with conventional solutions. The purpose of the present study was to investigate the effect of long-term intraperitoneal use of new, neutral dialysis solution (B/L) containing bicarbonate (25 mmol/L) and lactate (15 mmol/L) on peritoneal AGE accumulation and permeability. Normal male Sprague-Dawley rats were used. Twice daily for 12 weeks, 30 mL of new solution (B/L) or conventional solution [Lac (lactate 40 mmol/L)] was injected into the peritoneal cavity of the test rats. As a control, rats that were not injected were kept for 12 weeks in the same manner as the test rats. After 12 weeks, a 2-hour peritoneal equilibration test (PET) was performed in the test rats. After the PET, the parietal peritoneum and liver were obtained for evaluation of peritoneal morphology and for immunohistochemistry for AGE. Intensity of AGE staining was semi-quantitatively graded from 0 to 3. The omentum was also obtained and immediately frozen for analysis of pentosidine content by high-performance liquid chromatography. Compared with findings in the control group, hematoxylin and eosin staining of the parietal peritoneum and liver samples revealed partial denudation of mesothelial cells in the Lac group; denudation was not remarkable in the B/L group. The B/L solution showed significantly less AGE staining in the peritoneal cavity compared to conventional solution. However, B/L solution failed to lower pentosidine levels. Intraperitoneal volume and the ratio of dialysate glucose at 2 hours to dialysate glucose at instillation (D2/D0 glucose) were significantly lower and the ratio of dialysate urea to plasma urea at 2 hours (D2/P2 urea) was significantly higher in the Lac and B/L groups than in the control group. Intraperitoneal volume was significantly higher in the B/L group than in the Lac group; D2/D glucose and D2P2 urea did not differ between the two groups. In conclusion, peritoneal ultrafiltration decreased after long-term PD. The B/L solution showed a small but statistically significant protective effect against decreasing ultrafiltration as compared with Lac solution. The B/L solution attenuated peritoneal AGE accumulation compared with conventional solution, but did not affect peritoneal pentosidine levels. These findings indicate that biochemical kinetics of various AGE peptides are not unique, but multivalent.


Assuntos
Soluções para Diálise/farmacologia , Produtos Finais de Glicação Avançada/metabolismo , Animais , Bicarbonatos/química , Bicarbonatos/farmacologia , Soluções para Diálise/química , Glucose/metabolismo , Técnicas In Vitro , Ácido Láctico/química , Ácido Láctico/farmacologia , Fígado/metabolismo , Masculino , Cavidade Peritoneal/citologia , Peritônio/metabolismo , Peritônio/patologia , Ratos , Ratos Sprague-Dawley , Esterilização
15.
Perit Dial Int ; 19 Suppl 2: S68-74, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10406497

RESUMO

BACKGROUND: Glucose-containing dialysis solutions in peritoneal dialysis (PD) patients induce non enzymatic glycosylation (NEG) within the peritoneal cavity. The subsequent formation of advanced glycosylation end-products (AGEs) may be implicated in the functional deterioration of the peritoneal membrane in long-term PD patients. AIM OF THE STUDY AND PARAMETERS: Measurement of NEG by the determination of percent glycation of albumin and IgG (GP), and of AGEs by measuring pentosidine content of protein in 4-hour effluents (Peff) and serum. SUBJECTS: In 5 patients each, a comparison was made between 3.86% glucose and 1.36% glucose (GP and Peff), and between 3.86% glucose and 7.5% icodextrin (Peff). Nine patients with clinically severe ultrafiltration failure (UFF) were compared to nine patients treated with PD for 1 month. Six of the patients with UFF were treated with non glucose dialysis solutions and Peff was studied again after 6 weeks. RESULTS: No difference was found between Peff comparing 3.86% glucose to either 1.36% glucose or icodextrin. GP were higher in 3.86% glucose than in 1.36%. Glycated/non glycated (G/NG) protein clearance ratios were 1.29 for albumin and 1.12 for IgG (p = 0.003). In contrast to GP, both Peff and serum pentosidine were higher in the UFF patients than in the recently started patients. Peff, but not GP, correlated with duration of PD (r = 0.67, p = 0.04). In 5 of 6 patients treated with non glucose dialysate, Peff decreased while serum pentosidine was stable. DISCUSSION: These data show that 4-hour Peff contents are not influenced by glucose concentration or osmolality, in contrast to GP. The relation between Peff and duration of PD, and the effect of non glucose dialysate on Peff, suggest that long-term glucose exposure is an important determinant of membrane glycosylation. Thus Peff probably reflects the long-term effects of intraperitoneal glycosylation of peritoneal membrane proteins. Treatment with non glucose dialysis solutions may result in "washout" of glycosylated proteins from the peritoneal membrane.


Assuntos
Soluções para Diálise/química , Produtos Finais de Glicação Avançada/metabolismo , Diálise Peritoneal , Proteínas/metabolismo , Albuminas/análise , Arginina/análogos & derivados , Arginina/análise , Glucanos , Glucose , Glicosilação , Humanos , Icodextrina , Imunoglobulina G/análise , Lisina/análogos & derivados , Lisina/análise
16.
Biochem Biophys Res Commun ; 260(2): 332-8, 1999 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-10403771

RESUMO

Aging and age-related diseases are associated with the production of reactive oxygen species which modify lipids, proteins and DNA. Here we hypothesized the glyco- and lipoxidation product N(epsilon)-(carboxymethyl)lysine (CML) in proteins should bind divalent and redox active transition metal binding. CML-rich poly-L-lysine and bovine serum albumin (BSA) were chemically prepared and found to bind non-dialyzable Cu(2+), Zn(2+) and Ca(2+). CML-BSA-copper complexes oxidized ascorbate and depolymerized protein in the presence of H(2)O(2). CML-rich tail tendons implanted for 25 days into the peritoneal cavity of diabetic rats had a 150% increase in copper content and oxidized ascorbate three times faster than controls. CML-rich proteins immunoprecipitated from serum of uremic patients oxidized four times more ascorbate than control and generated spin adducts of DMPO in the presence of H(2)O(2). The chelator DTPA suppressed ascorbate oxidation thereby implicating transition metals in the process. In aging and disease, CML accumulation may result in a deleterious vicious cycle since CML formation itself is catalyzed by lipoxidation and glycoxidation.


Assuntos
Cobre/metabolismo , Diabetes Mellitus Experimental/metabolismo , Produtos Finais de Glicação Avançada , Falência Renal Crônica/metabolismo , Lisina/análogos & derivados , Animais , Ácido Ascórbico/metabolismo , Sítios de Ligação , Biopolímeros , Catálise , Cátions Bivalentes , Colágeno/metabolismo , Radicais Livres , Humanos , Peróxido de Hidrogênio/metabolismo , Lisina/metabolismo , Metilação , Oxirredução , Estresse Oxidativo , Peroxidase/metabolismo , Ratos , Ratos Sprague-Dawley , Serina/metabolismo
17.
Obstet Gynecol ; 93(4): 599-602, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10214841

RESUMO

OBJECTIVE: To evaluate outcomes of patients with stage IC endometrial carcinoma treated with external whole pelvic radiation but not vaginal brachytherapy. METHODS: Sixty-one women with stage IC endometrial carcinoma had postoperative pelvic radiation without vaginal brachytherapy. The median age was 69 years (range 44-87 years). Most subjects had histologic findings of adenocarcinoma (71%) and grade 2 or 3 disease (74%). The median pelvic irradiation dose was 48.6 Gy (range 43.2-50.4 Gy). No patients received adjuvant chemotherapy or hormonal therapy. The median follow-up time was 69.5 months (range 7-196 months). RESULTS: The 5-year actuarial disease-free and overall survivals of the entire group were 86.7% and 97.6%, respectively. No patient developed local (vaginal) recurrence. One patient had recurrent disease in the lateral pelvis. Ten patients (16.4%) had distant (extrapelvic) metastases. No serious sequelae were noted, including vaginal necrosis, small bowel obstruction, proctitis, or fistulae. CONCLUSION: Local control was excellent in stage IC endometrial carcinoma treated with adjuvant radiation therapy alone. Attention needs to be focused on efforts to control extrapelvic recurrence in patients with this disease.


Assuntos
Neoplasias do Endométrio/radioterapia , Análise Atuarial , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias do Endométrio/mortalidade , Neoplasias do Endométrio/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Taxa de Sobrevida , Resultado do Tratamento
18.
J Dairy Sci ; 82(3): 618-22, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10194682

RESUMO

A crossover design was implemented using four nonlactating dairy cows [mean body weight (BW) = 678 kg] and two rations to measure the true absorption of Ca and P from corn silage. True absorption was calculated after dosing cows intravenously with 45Ca and 32P to measure endogenous fecal losses. Rations consisted mainly of corn silage and were formulated to supply 32 g/d of Ca and 20 g/d of P or 16 g/d of Ca and 12 g/d of P. The percentages of total Ca and P that came from corn silage were 95 and 77%, respectively, for ration 1, and 98 and 79%, respectively, for ration 2. Cows ate more dry matter (10.9 vs. 10.2 kg/d) when consuming the corn silage in ration 1 than when consuming the corn silage in ration 2. Calcium intake was greater for cows fed ration 1 than for cows fed ration 2 (32.6 vs. 16.1 g/d), and P intake was greater for cows fed ration 1 than for cows fed ration 2 (20.1 vs. 11.7 g/d). True absorption of Ca was 34.4 and 43.7% for rations 1 and 2, respectively, and true absorption of P was 84.5 and 93.9% for rations 1 and 2, respectively. True absorption of Ca was about equal to values currently used in the National Research Council (NRC) feeding standards, but true absorption of P was higher than values currently used by the NRC. Fecal endogenous excretion of Ca (mean = 8.23 mg/kg of BW per d) was one-half of the value currently used by the NRC, and fecal endogenous excretion of P (mean = 7.23 mg/kg of BW per d) was only slightly less than NRC values.


Assuntos
Cálcio/farmacocinética , Bovinos/metabolismo , Valor Nutritivo , Fósforo/farmacocinética , Silagem , Zea mays , Absorção , Animais , Digestão , Fezes , Feminino , Necessidades Nutricionais , Gravidez
19.
Kidney Int ; 54(1): 193-202, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9648079

RESUMO

BACKGROUND: Patients with diabetic nephropathy experience a progressive and usually inexorable decline in renal function. The presence of the structurally defined advanced glycation end product (AGE) pentosidine on tissue and circulating proteins has been correlated with the severity of diabetic complications. METHODS: To delineate a role for this AGE in the progression of diabetic nephropathy, glycohemoglobin and free and protein-bound pentosidine were measured in baseline stored serum and urine from a subgroup of patients with diabetes mellitus and proteinuria originally followed by the Collaborative Study Group Trial. To delineate a potential role for an immune-activation response to AGEs, the inflammatory markers, interleukin-6 (IL-6), C-reactive protein (CRP), and the monocyte activation marker marker neopterin were also measured at baseline. The patients chosen represented 67 subjects whose creatinine levels had "doubled" over the course of the study whether or not they later were treated with captopril, and 67 paired "non-doublers." RESULTS: Baseline disease activity, as manifested by glycohemoglobin, serum creatinine and degree of proteinuria was equal in the two groups, as was protein-bound pentosidine and the immune-markers IL-6 and CRP. At baseline the "doublers" as compared to the "non-doublers" had elevated serum levels of free pentosidine and neopterin. Baseline increases in these two parameters were also associated with an increased rate of "doubling" of serum creatinine by the proportional hazards method. CONCLUSION: Differences in individual responsiveness to AGEs, as manifested by either the production of free pentosidine or its release from a protein-bound form, and by evidence of monocyte/macrophage activation, are associated with progression of diabetic nephropathy.


Assuntos
Arginina/análogos & derivados , Nefropatias Diabéticas/metabolismo , Lisina/análogos & derivados , Neopterina/sangue , Adulto , Inibidores da Enzima Conversora de Angiotensina/administração & dosagem , Arginina/sangue , Arginina/urina , Biomarcadores , Captopril/administração & dosagem , Creatinina/sangue , Reagentes de Ligações Cruzadas/metabolismo , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 1/mortalidade , Nefropatias Diabéticas/tratamento farmacológico , Nefropatias Diabéticas/mortalidade , Progressão da Doença , Método Duplo-Cego , Feminino , Hemoglobinas Glicadas/análise , Humanos , Lisina/sangue , Lisina/urina , Masculino , Neopterina/urina , Valor Preditivo dos Testes , Análise de Sobrevida
20.
J Surg Oncol ; 55(4): 222-8, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8159004

RESUMO

Autolymphocyte therapy (ALT) is adoptive cellular therapy of cancer using ex vivo activation of autologous peripheral blood lymphocytes (PBL). Memory T cells are the principal effector population in ALT, with in vivo activity in patients with metastatic renal cell carcinoma (RCC) and melanoma, and ex vivo cytotoxicity against autologous tumor targets. However, the noncytolytic lymphocyte portion of ex vivo-activated memory T cells (ALT cells) may also contribute as antitumor effectors. Pretreatment of murine and human tumor cells ex vivo with chemotherapeutic agents can enhance their susceptibility to antitumor lymphocytes ex vivo and in vivo. To determine whether cis-diamminedichloroplatinum(II) (DDP) could enhance ex vivo antitumor effects of ALT cells by immunomodulation, human breast and colorectal carcinoma target cells were derived from both primary and metastatic surgical specimens and incubated in complete medium (CM) with DDP or in CM alone (control group). Viability of each group was confirmed by trypan blue-dye exclusion test. ALT cells were prepared from autologous PBL at surgery. Primary and metastatic tumor cells from each group were used as targets for ALT cells and levels of interferon-gamma (IFN-gamma) release were measured as a determination of antitumor effect and recognition. Primary tumor target cells incubated in DDP showed enhanced antitumor effects and recognition by autologous ALT cells, as measured by the IFN-gamma assay compared to non-DDP-treated controls. Metastatic autologous tumor target cells demonstrated less IFN-gamma release than did the primary targets, although this was enhanced by pre-treating metastatic tumor targets with DDP. ALT cells demonstrated minimal IFN-gamma release when incubated with allogeneic tumor targets. These data suggest that autotumor recognition of metastatic tumor targets is comparable to that of primary lesions following ex vivo pretreatment of metastatic cells with nonlethal doses of certain chemotherapeutic agents. DDP may somehow alter the physical properties of target cells, rendering them susceptible to immune-mediated attack and the combination of ALT and DDP may lead to increased therapeutic efficacy in patients with metastatic breast and colon cancer.


Assuntos
Neoplasias da Mama/terapia , Cisplatino/uso terapêutico , Neoplasias Colorretais/terapia , Imunoterapia Adotiva , Linfócitos T/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/imunologia , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/imunologia , Terapia Combinada , Sinergismo Farmacológico , Feminino , Humanos , Interferon gama/biossíntese , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade , Linfócitos T/imunologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA