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4.
Springerplus ; 5: 16, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26759755

RESUMO

INTRODUCTION: Laparoscopy for abdominal surgical emergencies is gaining increasing acceptance given the spreading of advanced laparoscopic skills among modern surgeons, as it may allow at the same time an accurate diagnosis and appropriate treatment of acute abdomen. The use of the laparoscopic approach also in case of diffuse peritonitis is now becoming accepted provided hemodynamic stability, despite the common belief in the past decades that such severe condition represented an indication for conversion to open surgery or an immediate contraindication to continue laparoscopy. Crohn's Disease (CD) is a rare cause of acute abdomen and peritonitis, only a few cases of CD acute perforations are reported in the published literature; these cases have always been approached and treated by open laparotomy. CASE DESCRIPTION: We report on a case of a faecal peritonitis due to an acute perforation caused by a terminal ileitis in an undiagnosed CD. The patient underwent diagnostic laparoscopy followed by a laparoscopic ileo-colic resection and primary intracorporeal anastomosis, with a successful postoperative outcome. CONCLUSIONS: Complicated CD has to be considered within the possible causes of small bowel non-traumatic perforation. Emergency laparoscopy with resection and primary intra-corporeal anastomosis can be feasible and may be a safe and effective minimally invasive alternative to open surgery even in case of faecal peritonitis, in selected stable patients and in presence of appropriate laparoscopic colorectal surgical skills and experience. To the best of our knowledge the present experience is the first ever reported case managed with a totally laparoscopic extended ileocecal resection with intracorporeal anastomosis in case of acutely perforated CD and diffuse peritonitis.

5.
Minerva Anestesiol ; 80(11): 1205-16, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24472749

RESUMO

Management of liver trauma is challenging and may vary widely given the heterogeneity of liver injuries' anatomical configuration, the hemodynamic status, the settings and resources available. Perhaps the use of non-operative management (NOM) may have potential drawbacks and the role of damage control surgery (DCS) and angioembolization represents a major evolving concept.1 Most severe liver trauma in polytrauma patients accounts for a significant morbidity and mortality. Major liver trauma with extensive parenchymal injury and uncontrollable bleeding is therefore a challenge for the trauma team. However a safe and effective surgical hemostasis and a carefully planned multidisciplinary approach can improve the outcome of severe liver trauma. The technique of perihepatic packing, according to DCS approach, is often required to achieve fast, early and effective control of hemorrhage in the highest grades of liver trauma and in unstable patients. A systematic and standardized technique of perihepatic packing may contribute to improve hemostatic efficacy and overall outcomes if wisely combined in a stepwise "sandwich" multimodal approach. DCS philosophy evolved alongside with damage control resuscitation (DCR) in the management of trauma patients, requiring close interaction between surgery and resuscitation. Therefore, as a result of a combined surgical and critical care clinical audit activity in our western European trauma center, a practical algorithm for multimodal sequential management of liver trauma has been developed based on a historical cohort of 253 liver trauma patients and subsequently validated on a prospective cohort of 135 patients in the period 2010-2013.


Assuntos
Algoritmos , Fígado/lesões , Ferimentos e Lesões/cirurgia , Ferimentos e Lesões/terapia , Hemorragia/terapia , Humanos , Itália , Centros de Traumatologia
8.
J Cell Mol Med ; 11(4): 852-67, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17760845

RESUMO

To develop a non-human primate model of systemic bone loss after ovariectomy, 24 ovariectomized (OVX) and eight control (non-OVX) female baboons Papio ursinus were investigated over a period of 48 months using bone mineral density (BMD), iliac crest bone histomorphometry, bone turnover markers, and variables of calcium metabolism. Lumbar spine (L1-L4) BMD measured by dual energy X-ray absorptiometry (DXA) decreased in OVX animals in the first 12 months (-7.6%) and showed a slow trend towards recovery after 24 months. Controls showed a slow increase in spinal BMD over 4 years (+9.7%). Total hip BMD decreased slowly up to 48 months in all animals (OVX -12.6%versus controls -10%); this indicated that OVX had a limited effect on total hip BMD. Forearm BMD did not change. The significant decrease in trabecular bone volume (TBV) of the iliac crest from baseline to 12 months was followed by some recovery. Microarchitectural deterioration of trabecular bone in OVX animals was demonstrated by a decline in trabecular number and an increase in trabecular spacing. These changes were also evident on sections of whole vertebrae, proximal femora and iliac crests. Changes in iliac TBV reflected spinal but not hip BMD changes in the OVX animals. Static and dynamic histomorphometric variables indicated that bone turnover was increased for 36 months following OVX. Controls showed no changes in histomorphometric variables. Bone specific alkaline phosphatase (ALPs) in OVX animals remained elevated throughout the study; osteocalcin (OC) was significantly elevated only at 6 and 12 months, and deoxypyridinoline (Pyr-D) was elevated at 12 months but declined after 24 months. ALPs was thus more sensitive to the long-term effects of OVX than were OC or Pyr-D. Controls showed no changes in bone turnover markers. This study showed consistent deleterious changes in lumbar BMD, bone histomorphometry with microarchitectural deterioration together with altered biochemical markers of bone turnover in the first 12 months after OVX. Since these changes resemble those in post-menopausal women, the non-human primate Papio ursinus is suitable for the study of bone loss in post-menopausal women.


Assuntos
Reabsorção Óssea/patologia , Ovário/cirurgia , Absorciometria de Fóton , Fosfatase Alcalina/sangue , Aminoácidos/urina , Animais , Biomarcadores , Densidade Óssea , Reabsorção Óssea/fisiopatologia , Cálcio/urina , Feminino , Humanos , Ílio/patologia , Vértebras Lombares/patologia , Osteocalcina/sangue , Papio , Pelvimetria , Fosfatos/urina
9.
Ann Ital Chir ; 75(4): 407-13, 2004.
Artigo em Italiano | MEDLINE | ID: mdl-15754689

RESUMO

BACKGROUND: To evaluate if combining operative treatment of patients with trauma and general surgery emergencies offers a good operative experience and can be a model for a Trauma Center organization, we compare our surgical experience with that of our general surgeons. METHODS: We reviewed records to determine number of operation, need of intensive care unit care for patients treated, the after hours practice by the trauma and emergency surgeons and general surgeons over a 1-year period at Ospedale Maggiore of Bologna. RESULTS: Emergency and trauma surgeons performed more operations per surgeons (133.7 vs 102.6) and managed more patients in intensive care unit than general surgeons. 51.8% of emergency and trauma operations were after hours. CONCLUSION: The care of trauma and emergency patients resulted in a breadth and scope of practice for trauma and emergency surgeons compared well with that of general surgeons but in a worse lifestyle.


Assuntos
Centro Cirúrgico Hospitalar , Centros de Traumatologia , Ferimentos e Lesões/cirurgia , Emergências , Humanos , Unidades de Terapia Intensiva , Itália
10.
Ann Ital Chir ; 75(4): 421-5, 2004.
Artigo em Italiano | MEDLINE | ID: mdl-15754691

RESUMO

PURPOSE: To evaluate our 2-year experience in the emergency surgical treatment of elderly people (aged > or = 80). METHOD: A retrospective review was conducted of 198 elderly patients admitted to Emergency Surgery Unit of the Ospedale Maggiore in Bologna from 01.07.2001 to 30.06.2003. RESULTS: All the Patients were submitted to emergency operations. Mean age was 84.8 (range 80-96); Female were 152, male 73. Preexisting condition, ASA scores and surgical procedures were recorded. The postoperative mortality was 17.1%. The mean length of stay in our Unit was 9.7 days; 93 patients needed rehabilitation facility at discharge. CONCLUSION: The Authors concluded that emergency surgery entails a high risk to the patients, high cost in hospital resources and rehabilitation facility.


Assuntos
Idoso de 80 Anos ou mais , Procedimentos Cirúrgicos Operatórios , Fatores Etários , Idoso , Emergências , Feminino , Humanos , Tempo de Internação , Masculino , Mortalidade , Complicações Pós-Operatórias , Estudos Retrospectivos , Fatores de Risco , Procedimentos Cirúrgicos Operatórios/economia
11.
Ann Ital Chir ; 74(1): 37-41; discussion 41-3, 2003.
Artigo em Italiano | MEDLINE | ID: mdl-12870280

RESUMO

BACKGROUND: From the first successful splenectomy performed in 1893 the trend, in the management of splenic injuries has been increasingly toward avoiding splenectomy in favor of splenic preservation, either operatively or nonoperatively. The aim of this study is to evaluate our experience in the management of splenic injuries. METHOD: 429 Patients who suffered splenic injuries from 1989 to 2001, were examinated retrospectively. RESULTS: 120 Patients were treated non operatively; 270 were treated with splenectomy and 39 with operative preservation. The mortality rate was 6.8% but no Patient treated nonoperatively or with surgical preservation died. CONCLUSION: The splenic preservation either operatively or nonoperatively is the treatment of choice of splenic injuries in all Patients irrespective of the grade of injury or the age of the Patient.


Assuntos
Baço/lesões , Baço/cirurgia , Esplenectomia/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Drenagem , Eletrocoagulação/métodos , Feminino , Hemodinâmica/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Baço/irrigação sanguínea
12.
Gut ; 52(4): 580-5, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12631673

RESUMO

BACKGROUND AND AIMS: In chronic liver disease, bone disease frequently develops. The contributions of the different features of liver disease such as parenchymal inflammation, portal hypertension, and portasystemic shunting on bone metabolism have not been systematically studied. The aim of this study was to identify the features of liver disease contributing to bone disease using rat models. METHODS: Parenchymal liver disease was induced by carbon tetrachloride administration, portal hypertension by partial portal vein ligation, and portasystemic shunting by end to side anastomosis of the portal vein to the inferior vena cava. Normal and sham operated surgical animals served as controls. Serum calcium, 25-hydroxy vitamin D (25-OH vit D), and osteocalcin levels, and urinary deoxypyridinoline excretion were analysed. Testosterone and oestradiol levels were determined in male and female rats, respectively. Interleukin 1, interleukin 6, and tumour necrosis factor alpha (TNF-alpha) were determined in serum. Bone density was measured in all groups and in addition, in the surgical groups, histomorphometry was performed on undecalcified specimens of the proximal tibia. The calcium content of the femurs, removed at termination and ashed, was determined. RESULTS: Early parenchymal disease and portal hypertension did not affect bone metabolism or body mass. Portasystemic shunting increased bone resorption, decreased bone formation, bone density, and trabecular bone volume which were commensurate with a reduction in body mass. TNF-alpha levels were elevated and testosterone levels were low in male portasystemic shunted rats. CONCLUSIONS: Portasystemic shunting in the rat adversely affects bone metabolism as part of a generalised catabolic state where high TNF-alpha and low testosterone and 25-OH vit D levels may play a role.


Assuntos
Hipertensão Portal/complicações , Cirrose Hepática Experimental/complicações , Osteoporose/etiologia , Derivação Portossistêmica Cirúrgica/efeitos adversos , Absorciometria de Fóton , Animais , Densidade Óssea , Tetracloreto de Carbono , Modelos Animais de Doenças , Feminino , Cirrose Hepática Experimental/induzido quimicamente , Masculino , Ratos , Ratos Sprague-Dawley , Tíbia/fisiopatologia , Fator de Necrose Tumoral alfa/metabolismo
13.
Ann Ital Chir ; 74(5): 529-33; discussion 534, 2003.
Artigo em Italiano | MEDLINE | ID: mdl-15139708

RESUMO

PURPOSE: To evaluate our 12-year experience in the treatment of complex hepatic injuries with periepatic packing and damage control priciples. METHOD: A retrospective review was conducted of 21 Patients with grade IV-V injuries of the liver and severe haemorrage induced hypothermia and acidosis admitted to the Ospedale Maggiore Trauma Center in Bologna from 1989 to 2001 RESULTS: All the Patients had major blunt trauma. Mean age was 39.6; mean ISS 41.5; mean RTS 4.13; extimated loss of blood was greater than 5300 ml. Packing provide definitive control of bleeding in 16 Patients but 10 had recurrent bleeding or bleeding from different injuries such as bone fractures and required further surgery or arterial embolization. 12 Patients died (57.2%). Survival was strongly associated with the ISS, GCS, the loss of blood and acidosis. CONCLUSION: The authors concluded that in selected circumstances the traditional approach to hepatic injuries is not appropiate. In this situation, alternative and aggressive treatment--damage control--has been recommended as the procedure of choice.


Assuntos
Técnicas Hemostáticas , Fígado/lesões , Fígado/cirurgia , Traumatismo Múltiplo/terapia , Ferimentos não Penetrantes/terapia , Ferimentos Penetrantes/terapia , Adolescente , Adulto , Idoso , Criança , Feminino , Hepatectomia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
14.
Biocell ; 25(1): 43-51, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11387876

RESUMO

Ethidium bromide (EB) is an intercalating agent which binds specifically to the kinetoplast (mitochondrial) DNA (kDNA) of trypanosomatids. Accordingly, EB inhibits DNA replication, thus inducing dyskinetoplasty. Since in eukariotic organisms mitochondrial DNA encodes the genetic information for cytochromes b, aa3 and F0F1 ATPase, it seemed of interest to establish whether a similar effect occurs in Crithidia fasciculata, a trypanosomatid used for assay of potential trypanocidal drugs. Culturing of C. fasciculata in the presence of EB inhibited growth and induced dyskinetoplasty, as confirmed by electron microscopy. The kinetoplast of EB-cultured crithidia lost its characteristic arc shape, it was misplaced in the cell cytoplasm its matrix structure and membrane differentiation were specifically modified. Dyskinetoplasty decreased crithidia respiration and oxidative phosphorylation, as indicated by the lower ATP level, ATP/ADP ratio and adenylate energy charge. The interference of EB with kinetoplastic constituents synthesis was confirmed by the lack of action of EB on crithidia in the stationary phase of growth, that ruled out direct inhibition of oxidative phosphorylation enzymes. The lipophilic o-naphthoquinone beta-lapachone produced structural alterations in kinetoplast membranes, that correlated with inhibition of oxidative phosphorylation. These latter effects involved free radicals since they were prevented by free radical scavengers.


Assuntos
Crithidia fasciculata/efeitos dos fármacos , DNA de Cinetoplasto/metabolismo , Etídio/farmacologia , Mitocôndrias/efeitos dos fármacos , Fosforilação Oxidativa/efeitos dos fármacos , Tripanossomicidas/farmacologia , Trifosfato de Adenosina/metabolismo , Animais , ATPase de Ca(2+) e Mg(2+)/metabolismo , Crithidia fasciculata/fisiologia , Crithidia fasciculata/ultraestrutura , DNA de Cinetoplasto/genética , Mitocôndrias/genética , Mitocôndrias/metabolismo , Mitocôndrias/ultraestrutura , Naftoquinonas/farmacologia , Compostos de Sulfidrila/farmacologia
15.
Biocell ; 25(1): 43-51, 2001 Apr.
Artigo em Inglês | BINACIS | ID: bin-39521

RESUMO

Ethidium bromide (EB) is an intercalating agent which binds specifically to the kinetoplast (mitochondrial) DNA (kDNA) of trypanosomatids. Accordingly, EB inhibits DNA replication, thus inducing dyskinetoplasty. Since in eukariotic organisms mitochondrial DNA encodes the genetic information for cytochromes b, aa3 and F0F1 ATPase, it seemed of interest to establish whether a similar effect occurs in Crithidia fasciculata, a trypanosomatid used for assay of potential trypanocidal drugs. Culturing of C. fasciculata in the presence of EB inhibited growth and induced dyskinetoplasty, as confirmed by electron microscopy. The kinetoplast of EB-cultured crithidia lost its characteristic arc shape, it was misplaced in the cell cytoplasm its matrix structure and membrane differentiation were specifically modified. Dyskinetoplasty decreased crithidia respiration and oxidative phosphorylation, as indicated by the lower ATP level, ATP/ADP ratio and adenylate energy charge. The interference of EB with kinetoplastic constituents synthesis was confirmed by the lack of action of EB on crithidia in the stationary phase of growth, that ruled out direct inhibition of oxidative phosphorylation enzymes. The lipophilic o-naphthoquinone beta-lapachone produced structural alterations in kinetoplast membranes, that correlated with inhibition of oxidative phosphorylation. These latter effects involved free radicals since they were prevented by free radical scavengers.

17.
J Clin Densitom ; 3(1): 49-55, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10917741

RESUMO

The rabbit could be a superior animal model to use in bone physiology studies, for the rabbit does attain true skeletal maturity. However, there are neither normative bone mineral density (BMD) data on the rabbit nor are there any validation studies on the use of dual-energy X-ray absorptiometry (DXA) to measure spinal BMD in the rabbit. Therefore, our aim was twofold: first, to investigate whether DXA could be used precisely and accurately to determine the bone mineral content (BMC). bone area (BA). and BMD of the rabbit lumbar spine: Second. to evaluate the new generation fan-beam DXA (Hologic QDR-4500) with small animal software by comparing two DXA methodologies QDR-1000 and QDR-4500 with each other, as well as against volumetric bone density (VBMD) derived from Archimedes principle. As expected. there was a magnification error in the QDR-4500 (BMC, BA. and BMD increased by 52%. 38%. and 10%, respectively, when the vertebrae were positioned flat against the scanning table). With the magnification error kept constant (vertebrae positioned 10 cm above the scanning table to match the height in vivo). there were no differences among the mean BMC. BA. and BMD of the rabbit vertebrae (Ll-L7) in vivo and in vitro using the QDR-4500 (p > 0.05). BMC, BA, and BMD differed between QDR-1000 and QDR-4500 in vitro because of a magnification error when the vertebrae were flat on the table (p <0.0001). and, consequently. the machines did not correlate with one another (p > 0.05). However, the BMC, BA, and BMD of the two DXAs did significantly correlate with each other in vivo and in vitro when the magnification error was compensated for (r = 0.44 and 0.52. i2 = 0.45 and 0.63. and 12 = 0.41 and 0.60. respectively. p < 0.05-0.008). The BMC and BMD (in vivo and in vitro) of the rabbit vertebrae measured by QDR-4500 was significantly correlated with VMBD, ash weight, and mineral content (,2 = 0.67-0.90,j <0.01-0.0001). Therefore, the QDR-4500 can be used to yield precise and accurate measurements of the rabbit spine.


Assuntos
Absorciometria de Fóton , Densidade Óssea , Vértebras Lombares/fisiologia , Análise de Variância , Animais , Feminino , Imagens de Fantasmas , Coelhos , Software
18.
Minerva Chir ; 52(3): 289-93, 1997 Mar.
Artigo em Italiano | MEDLINE | ID: mdl-9148220

RESUMO

Insulinoma is the most common endocrine tumor of the pancreas. It arises from the beta-islet cells of Langerhans. Insulinomas synthesize and secrete insulin autonomously in the presence of low blood glucose levels, causing spontaneous hypoglycemia and characteristic clinical symptoms. The authors examined data the from the most important international research projects on this topic during the past 20 years. Insulinomas are rare, with an annual incidence of 0.5 per million population. Up to 90% patients have benign solitary pancreatic insulinomas. People of all ages can be affected with this neoplasm. The authors reported a case of a large insulinoma of the body and tail of the pancreas, with atypical psychic symptoms. A distal pancreatectomy with splenectomy was performed. No surgical complications occurred in the postoperative course. The psychic symptoms were emphasized with refusal of food. The patient underwent Parenteral Nutrition and was discharged 24 days after the operation. The surgical removal of the tumor permitted the patient to recover completely, with glucose and insulin blood levels in normal range.


Assuntos
Insulinoma , Neoplasias Pancreáticas , Diagnóstico Diferencial , Humanos , Insulinoma/diagnóstico , Insulinoma/patologia , Insulinoma/cirurgia , Masculino , Pessoa de Meia-Idade , Pâncreas/patologia , Pancreatectomia , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/cirurgia
19.
Medicina (B Aires) ; 55(5 Pt 1): 397-407, 1995.
Artigo em Espanhol | MEDLINE | ID: mdl-8728769

RESUMO

Inactivation of lipoamide dehydrogenase (LipDH) by the Cu(II)/H2O2 Fenton system (SF-Cu(II): (5.0 microM Cu(II), 3.0 mM H2O2) was enhanced by catecholamines (CAs), namely, epinephrine, levoDOPA (DOPA), DOPAMINE, 6-hydroxyDOPAMINE (OH-DOPAMINE) and related compounds (DOPAC, CATECHOL, etc.). After 5 min incubation with the Cu(II)/H2O2/CA system (0.4 mM CA), the enzyme activity decayed as indicated by the following percentage values (mean +/- S.D.; in parenthesis, number of determinations): SF-Cu(II) alone, 43 +/- 10 (18); SF-Cu(II) + epinephrine, 80 +/- 9 (5); SF-Cu(II) + DOPA, 78 +/- 2 (4); SF + Cu(II) + DOPAMINE, 88 +/- 7 (5); SF-Cu(II) + OH-DOPAMINE 87 +/- 6 (7); SF-Cu(II) +/- DOPAC, 88 +/- 3 (6); SF-Cu(II) + catechol, 85 +/- 6 (5). In all cases P < 0.05, with respect to the SF-Cu(II) control sample. CAs effect was concentration-dependent and at the 0-100 microM concentration range, it varied with the CA structure. Above the 100 microM concentration, CAs were equally effective and produced 90-100% enzyme, inactivation (Figure 2). In the absence of oxy-radical generation, the enzyme specific activity (mean +/- S.D.) was 149 +/- 10 (24) mumol NADH/min/mg protein. Assay of HO. production by the Cu(II)/H2O2/CA system in the presence of deoxyribose (TBA assay) yielded values much greater than those obtained omitting CA. Hydroxyl radical production depended on the presence of Cu(II) and H2O2 and significant H. values were obtained with OH-DOPAMINE, DOPAC, epinephrine, DOPAMINE, DOPA and catecol supplemented systems (Table 2). LipDH (1.0 microM) inhibited 50-80% deoxyribose oxidation, the inhibition depending on the CA structure (Table 2). Native catalase (20 micrograms/ml) and bovine serum albumin (40 micrograms/ml) effectively prevented LipDH inactivation by the Cu(II)/H2O2/CA system; denaturated catalase, SOD, 0.3 M mannitol, 6.0 mM ethanol and 0.2 M benzoate were less effective or did not protect LipDH (Table 3). Incubation of CAs with the Cu(II)/H2O2 system produced a time and Cu(II)-dependent destruction of CAs, the corresponding o-quinone, production as illustrated with epinephrine (figures 6 and 7), as illustrated with epinephrine and DOPAMINE (Table 4). These results support LipDH inactivation by (a) reduction of Cu(II) to Cu(I) by CAs followed by Cu-catalyzed production of HO. from H2O2; (b) CA oxidation followed by the corresponding o-quinone interaction with LipDH. CAPTOPRIL, N-acetylcysteine, mercaptopropionylglycine and penicillamine prevented to various degree LipDH inactivation by the Cu(II)/H2O2/CA systems (Table 1). The former was the most effective and 0.4 mM CAPTOPRIL prevented about 95-100% the effect of Cu(II)/H2O2/CA systems supplemented with epinephrine, DOPAMINE and OH-DOPAMINE (Figures 3 and Table 1). LipDH increased and CAPTOPRIL inhibited epinephrine oxidation by Cu(II)/H2O2 (Figures 4 and 5). Since un-physiological concentrations of CAs and Cu(II) may be released in the myocardium after ischemia-reperfusion, the summarized observations may contribute to explain myocardial damage in that condition.


Assuntos
Catecol Oxidase/química , Catecolaminas/farmacologia , Di-Hidrolipoamida Desidrogenase/antagonistas & inibidores , Captopril/farmacologia , Catecolaminas/química , Cromatografia Líquida de Alta Pressão , Di-Hidrolipoamida Desidrogenase/metabolismo , Interações Medicamentosas , Espectrofotometria , Compostos de Sulfidrila/farmacologia
20.
Medicina [B Aires] ; 55(5 Pt 1): 397-407, 1995.
Artigo em Espanhol | BINACIS | ID: bin-37124

RESUMO

Inactivation of lipoamide dehydrogenase (LipDH) by the Cu(II)/H2O2 Fenton system (SF-Cu(II): (5.0 microM Cu(II), 3.0 mM H2O2) was enhanced by catecholamines (CAs), namely, epinephrine, levoDOPA (DOPA), DOPAMINE, 6-hydroxyDOPAMINE (OH-DOPAMINE) and related compounds (DOPAC, CATECHOL, etc.). After 5 min incubation with the Cu(II)/H2O2/CA system (0.4 mM CA), the enzyme activity decayed as indicated by the following percentage values (mean +/- S.D.; in parenthesis, number of determinations): SF-Cu(II) alone, 43 +/- 10 (18); SF-Cu(II) + epinephrine, 80 +/- 9 (5); SF-Cu(II) + DOPA, 78 +/- 2 (4); SF + Cu(II) + DOPAMINE, 88 +/- 7 (5); SF-Cu(II) + OH-DOPAMINE 87 +/- 6 (7); SF-Cu(II) +/- DOPAC, 88 +/- 3 (6); SF-Cu(II) + catechol, 85 +/- 6 (5). In all cases P < 0.05, with respect to the SF-Cu(II) control sample. CAs effect was concentration-dependent and at the 0-100 microM concentration range, it varied with the CA structure. Above the 100 microM concentration, CAs were equally effective and produced 90-100


enzyme, inactivation (Figure 2). In the absence of oxy-radical generation, the enzyme specific activity (mean +/- S.D.) was 149 +/- 10 (24) mumol NADH/min/mg protein. Assay of HO. production by the Cu(II)/H2O2/CA system in the presence of deoxyribose (TBA assay) yielded values much greater than those obtained omitting CA. Hydroxyl radical production depended on the presence of Cu(II) and H2O2 and significant H. values were obtained with OH-DOPAMINE, DOPAC, epinephrine, DOPAMINE, DOPA and catecol supplemented systems (Table 2). LipDH (1.0 microM) inhibited 50-80


deoxyribose oxidation, the inhibition depending on the CA structure (Table 2). Native catalase (20 micrograms/ml) and bovine serum albumin (40 micrograms/ml) effectively prevented LipDH inactivation by the Cu(II)/H2O2/CA system; denaturated catalase, SOD, 0.3 M mannitol, 6.0 mM ethanol and 0.2 M benzoate were less effective or did not protect LipDH (Table 3). Incubation of CAs with the Cu(II)/H2O2 system produced a time and Cu(II)-dependent destruction of CAs, the corresponding o-quinone, production as illustrated with epinephrine (figures 6 and 7), as illustrated with epinephrine and DOPAMINE (Table 4). These results support LipDH inactivation by (a) reduction of Cu(II) to Cu(I) by CAs followed by Cu-catalyzed production of HO. from H2O2; (b) CA oxidation followed by the corresponding o-quinone interaction with LipDH. CAPTOPRIL, N-acetylcysteine, mercaptopropionylglycine and penicillamine prevented to various degree LipDH inactivation by the Cu(II)/H2O2/CA systems (Table 1). The former was the most effective and 0.4 mM CAPTOPRIL prevented about 95-100


the effect of Cu(II)/H2O2/CA systems supplemented with epinephrine, DOPAMINE and OH-DOPAMINE (Figures 3 and Table 1). LipDH increased and CAPTOPRIL inhibited epinephrine oxidation by Cu(II)/H2O2 (Figures 4 and 5). Since un-physiological concentrations of CAs and Cu(II) may be released in the myocardium after ischemia-reperfusion, the summarized observations may contribute to explain myocardial damage in that condition.

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