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BACKGROUND: The data about cardiovascular (CV) changes in patients with asymptomatic primary hyperparathyroidism (PHPT) are scarce. AIM: The aim of this study is to compare cardiac structure and functions in patients with asymptomatic PHPT and controls by using tissue Doppler echocardiography. SUBJECTS AND METHODS: Thirty-eight patients with asymptomatic PHPT and 31 sex- and age-matched controls with similar cardiac risk factors were evaluated. RESULTS: There was no significant difference in ejection fraction (EF) between the patients and the controls [64±5.95 vs 62±3.25% (p=0.094)]. Left ventricular mass index (LVMI) was significantly higher in patients than controls [105.96 (66.45-167.24) vs 93.79 (64.25- 139.25) g/m2, p=0.014]. There was a significant correlation between LVMI and serum calcium (Ca) (r=0.240, p<0.005). Myocardial performance index (MPI) was significantly higher in patients than controls [0.49 (0.35-0.60) vs 0.39 (0.33-0.62), p<0.001]. There was positive correlation between theMPI and serumCa levels (r=0.505, p<0.001), parathyroid hormone (PTH) levels (r=0.464, p<0.001) and LVMI (r=0.270, p<0.005). When the normotensive patients and controls were evaluated, the difference between the groups remained statistically significant considering LVMI and MPI [109 (66.45-167.24) g/m2 vs 94.17 (64.25-75.10) g/m2, p=0.03; and 0.49 (0.35-0.60) vs 0.39 (0.33-0.62), p<0.01, respectively]. There were significant correlations between MPI and Ca (r=0.566, p<0.001), and PTH (r=0.472, p<0.001). CONCLUSIONS: Our study results showed that cardiacmorphology and diastolic functions are altered in the patients with asymptomatic PHPT. High serum PTH and Ca levels may have an impact on these CV changes. Whether these subtle CV changes would affect cardiac systolic functions and mortality in patients with asymptomatic PHPT should be investigated in further prospective studies.
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Corazón/anatomía & histología , Corazón/fisiopatología , Hiperparatiroidismo Primario/fisiopatología , Presión Sanguínea , Estudios de Casos y Controles , Ecocardiografía Doppler , Femenino , Estudios de Seguimiento , Humanos , Hiperparatiroidismo Primario/complicaciones , Hiperparatiroidismo Primario/diagnóstico por imagen , Hiperparatiroidismo Primario/cirugía , Hipertrofia Ventricular Izquierda/etiología , Hipertrofia Ventricular Izquierda/metabolismo , Hipertrofia Ventricular Izquierda/patología , Masculino , Persona de Mediana Edad , Hormona Paratiroidea/metabolismo , Paratiroidectomía , Pronóstico , Factores de RiesgoRESUMEN
PurposeTo evaluate aqueous humor (AH) pentraxin-3 (PTX3) levels in diabetic patients with and without diabetic retinopathy (DR).MethodsIn this prospective study, patients undergoing cataract surgery were enrolled. The study group was composed of 26 type-2 diabetic patients without DR (group 1), 32 diabetic patients with DR (group 2) and 29 age-matched subjects without any systemic disease (group 3). Fifteen proliferative DR (PDR) and 17 non-proliferative DR (NPDR) patients were enrolled in Group 2. HbA1c levels and duration of diabetes were noted. AH samples were obtained from anterior chamber at the beginning of cataract surgery and PTX3 levels were analyzed with Elisa kit.ResultsBaseline demographic characteristics were similar between groups. The mean duration of diabetes was 11.9±7.9 years in group 1 and 15.8±7.8 years in group 2 (P=0.11). The mean plasma HbA1c levels in group 1 was 9.1±2.6 and 8.2±2.4 in group 2 (P=0.36). PTX3 levels were 5.75±0.41 in group 1, 6.11±1.47 in group 2 and 4.93±0.84 ng/ml in group 3 (P=0.01). PTX3 levels in group 2 were higher than in group 1 and 3 (P=0.06 and P=0.01, respectively). There was no correlation between HbA1c and PTX3 levels (P=0.06 r=0.57, P=0.19 r=0.3, respectively). The mean PTX3 was 6.6±0.3 in PDR group and 5.6±0.5 ng/ml in NPDR group (P=0.04).ConclusionsPTX3 is an important marker especially for vascular endothelial damage. Since diabetic vascular changes are dependent on endothelial cell damage, high levels of AH PTX3 of DR patients may indicate the importance of PTX3 protein in the pathogenesis of DR.
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Humor Acuoso/metabolismo , Proteína C-Reactiva/metabolismo , Retinopatía Diabética/metabolismo , Componente Amiloide P Sérico/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores/metabolismo , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/metabolismo , Retinopatía Diabética/etiología , Ensayo de Inmunoadsorción Enzimática , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de TiempoRESUMEN
Oxygen free radicals may be implicated in the pathogenesis of ischemia-reperfusion damage. It is known that 2-chloroadenosine (2-CADO) has neuromodulatory effects and prevents the neuronal damage seen in the period of postischemia reperfusion. However, direct effects of 2-CADO on lipid peroxidation have not been investigated previously. The attack on the cell membrane by free radicals leads to lipid peroxidation, which can be assayed by the malondialdehyde (MDA) level. The aim of this study was to determine the effect of 2-CADO therapy on lipid peroxidation in experimental forebrain ischemia and postischemia reperfusion in Mongolian gerbils. Cerebral ischemia was induced by a bilateral 30-mm occlusion of the common carotid arteries. 2-Chloroadenosine (0.6 mg/kg, IV) was administered 5 min subsequent to ischemia. Ischemia was followed by reperfusion for 30 min. The MDA level was measured by the thiobarbituric acid (TBA) test. Bilateral carotid artery occlusion for 30 min in gerbils resulted in no significant change in MDA level in the brain. The MDA level was higher in postischemia reperfusion than in the ischemic group. 2-Chloroadenosine treatment did not change the MDA level in the ischemic period. However, the MDA level recovered significantly upon 2-CADO therapy during reperfusion following ischemia. These results suggest that 2-CADO may offer some degree of protection against oxidative stress in cerebral ischemia-reperfusion damage.
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2-Cloroadenosina/uso terapéutico , Peroxidación de Lípido/efectos de los fármacos , Peróxidos Lipídicos/metabolismo , Fármacos Neuroprotectores/uso terapéutico , Prosencéfalo/efectos de los fármacos , Daño por Reperfusión/prevención & control , Animales , Evaluación Preclínica de Medicamentos , Femenino , Gerbillinae , Masculino , Malondialdehído/metabolismo , Prosencéfalo/irrigación sanguínea , Prosencéfalo/patología , Daño por Reperfusión/metabolismo , Tiobarbitúricos/metabolismoRESUMEN
Ocular melanin pigment has antioxidant effect against excess of dispersed light. To investigate whether it has a similar effect in ocular inflammations, we used albino and pigmented guinea pigs and measured retinal glutathione peroxidase activities and lipid peroxide levels (expressed as thiobarbituric acid reactive substances) in a model of lens induced uveitis. Although the increase in the levels of the retinal lipid peroxides were higher in the albino group (204%, p < 0.05), the decrease in the activities of glutathione peroxidase were higher in pigmented guinea pigs (26%, p < 0.005). The results of the study suggest that pigmentless animals are more sensitive to the ocular inflammations, and ocular melanin pigment may act as an endojen antioxidant in lens induced uveitis.
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Antioxidantes , Modelos Animales de Enfermedad , Melaninas/fisiología , Uveítis/metabolismo , Animales , Cristalinas/inmunología , Radicales Libres , Glutatión Peroxidasa/metabolismo , Cobayas , Peroxidación de Lípido , Peróxidos Lipídicos/metabolismo , Retina/metabolismo , Sustancias Reactivas al Ácido Tiobarbitúrico/metabolismo , Uveítis/inmunologíaRESUMEN
BACKGROUND: The free radical balance of the eye may be changed by excimer laser keratectomy. Previous studies have demonstrated that excimer laser keratectomy increases the corneal temperature, decreases the superoxide dismutase activity of the aqueous, and induces lipid peroxidation in the superficial corneal stroma. Aldehyde dehydrogenase (ALDH) and glutathione S-transferase (GST) are known to play an important role in corneal metabolism, particularly in detoxification of aldehydes, which are generated from free radical reactions. METHODS: In three groups of guinea pigs mechanical corneal de-epithelialisation was performed in group I, superficial corneal photoablation in group II, and deep corneal photoablation in group III, and the corneal ALDH and GST activities measured after 48 hours. RESULTS: The mean ALDH and GST activities of group I and II showed no differences compared with the controls (p > 0.05). The corneal ALDH activities were found to be significantly decreased (p < 0.05) and GST activities increased (p < 0.05) in group III. CONCLUSION: These results suggest that excimer laser treatment of high myopia may change the ALDH and GST activities, metabolism, and free radical balance of the cornea.
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Aldehído Deshidrogenasa/análisis , Córnea/enzimología , Glutatión Transferasa/análisis , Queratectomía Fotorrefractiva/efectos adversos , Animales , Córnea/efectos de la radiación , Lesiones Oculares/enzimología , Lesiones Oculares/etiología , Cobayas , Láseres de ExcímerosRESUMEN
PURPOSE: To investigate the level of ascorbic acid in human tear fluid after photorefractive keratectomy (PRK), transepithelial PRK, and laser in situ keratomileusis (LASIK). SETTING: Departments of Ophthalmology and Biochemistry, School of Medicine, Gazi University, Ankara, Turkey. METHODS: Twenty patients (7 women and 13 men) were included in this study. Traditional PRK with epithelial scraping by a blunt spatula followed by surface ablation (7 eyes), transepithelial PRK (7 eyes), or LASIK (6 eyes) was performed. Tears were collected preoperatively and 1 and 5 days postoperatively. Ascorbic acid levels were measured using 2-4 dinitrophenylhydrazine. RESULTS: Ascorbic acid levels in the tear fluid were decreased significantly 1 day after PRK, transepithelial PRK, and LASIK (P <.05). On the fifth day, the ascorbic acid levels were significantly lower than preoperatively in all groups. CONCLUSION: After PRK, transepithelial PRK, and LASIK, the ascorbic acid levels of the tear fluid decreased significantly. Because ascorbic acid is the major scavenger of superoxide radicals in tears, topical ascorbic acid therapy may help eliminate the harmful effect of free radicals from excimer laser surgery.
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Ácido Ascórbico/metabolismo , Queratomileusis por Láser In Situ , Queratectomía Fotorrefractiva , Lágrimas/metabolismo , Adulto , Córnea/metabolismo , Córnea/cirugía , Femenino , Humanos , Láseres de Excímeros , Masculino , Miopía/metabolismo , Miopía/cirugíaRESUMEN
BACKGROUND: In the management of mild acute biliary pancreatitis, it is generally recommended to perform laparoscopic cholecystectomy after the subsidence of the attack during the same hospital admission. The effect of laparoscopy on abdominal organs has been widely investigated but not in acute pancreatitis. This study used an animal model of mild acute pancreatitis to examine the effects of CO(2) pneumoperitoneum on acute pancreatitis in rats. METHODS: Mild acute pancreatitis was induced in 30 male Sprague-Dawley rats by surgical ligation of the biliopancreatic duct. After 2 days, animals were assigned to three groups: sham operation (animals were anesthetized for 30 min without undergoing laparotomy), CO(2) pneumoperitoneum (applied for 30 min at a pressure of 12 mmHg), and laparotomy (performed for 30 min, and then the abdomen was closed). Two hours after the surgical procedures, animals were killed and levels of lactate dehydrogenase, aspartate aminotransferase, glucose, urea, hematocrit, and leukocyte count among Ranson's criteria and levels of amylase, lipase, and total bilirubin were measured to determine the severity of acute pancreatitis. Histopathologic examination of the pancreas was done, and malondialdehyde and glutathione levels of the pancreas and lung were determined. RESULTS: The only significant differences between the groups were in lactate dehydrogenase and aspartate aminotransferase levels, which were significantly higher in the pneumoperitoneum group compared to the sham operation group. CONCLUSION: CO(2) pneumoperitoneum for 30 min at a pressure of 12 mmHg did not affect the severity of acute pancreatitis induced by ligation of the biliopancreatic duct in rats.
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Dióxido de Carbono/farmacología , Pancreatitis , Neumoperitoneo Artificial , Enfermedad Aguda , Animales , Masculino , Pancreatitis/sangre , Ratas , Ratas Sprague-Dawley , Índice de Severidad de la EnfermedadRESUMEN
BACKGROUND AND OBJECTIVES: We report on the use of intravenous (IV) high-dose lidocaine to relieve diabetic neuropathic pain, and the technique's effects on clinical measures of lipid peroxidation. METHODS: Under continuous electrocardiogram monitoring, IV lidocaine (5 mg kg(-1) in 100 mL saline) was administered over 30 minutes to 7 non-insulin-dependent diabetic patients suffering from neuropathic pain who reported increased pain within the preceding 6 months. This treatment was performed once a week for 1 month. Blood samples were collected from the contralateral limb to determine plasma superoxide dismutase (SOD) and malondialdehyde (MDA) levels on admission and following the final lidocaine administration. RESULTS: Plasma MDA concentrations significantly decreased after the final IV lidocaine treatment (P < .05, paired t-test), whereas SOD levels did not show a statistically significant difference compared with baseline levels. CONCLUSIONS: High-dose lidocaine treatment lessens MDA levels, a marker of free-radical-mediated cell damage. This suggests that one of lidocaine's mechanism of action may be its effect on oxygen free radicals, which in turn impacts lipid peroxidation.
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Anestésicos Locales/efectos adversos , Diabetes Mellitus Tipo 2/metabolismo , Lidocaína/efectos adversos , Malondialdehído/metabolismo , Superóxido Dismutasa/metabolismo , Adulto , Anestésicos Locales/administración & dosificación , Anestésicos Locales/uso terapéutico , Diabetes Mellitus Tipo 2/complicaciones , Neuropatías Diabéticas/complicaciones , Femenino , Humanos , Lidocaína/administración & dosificación , Lidocaína/uso terapéutico , Masculino , Dolor/tratamiento farmacológico , Dolor/etiología , Dimensión del Dolor , Factores de TiempoRESUMEN
IL-8 is a potent chemoattractant which has been postulated to play a role in the cytokine cascade associated with uveitis. The authors studied the effect of intravitreal IL-8 on the induction of uveitis in the rabbit. IL-8 at varying concentrations (1 ng, 10 ng or 100 ng) or endotoxin (100 ng) was injected intravitreally within the rabbit eye. At 6, 24 and 48 hours following injection the induction of uveitis was evaluated by clinical scoring, anterior chamber (AC) leukocyte count, AC protein concentration and histopathology in 15 rabbits. Only the 100 ng concentration of IL-8 induced uveitis at 6 and 24 hours by clinical scoring and AC leukocyte count; the AC protein concentration remained normal. In contrast, endotoxin caused a severe uveitis with a significant increase in all the parameters evaluated. The authors conclude that intravitreal IL-8, in the concentrations studied, induces a limited uveitis which is detectable at six hours and resolves within 48 hours. It is characterized by leukocyte infiltration without an increased AC protein concentration. Thus, IL-8 may play a role in the cytokine cascade involved in the induction of uveitis.
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OBJECTIVE: To evaluate the effect of arthrocentesis and sodium hyaluronate (SH) injections on nitrite, nitrate, and thiobarbituric acid-reactive substance (TBA-RS) levels in temporomandibular joint internal derangements. STUDY DESIGN: Arthrocentesis was performed on 10 patients, and 15 patients received a supplemental injection of SH after arthrocentesis. All these patients received an SH injection 15 days after the first intervention. The synovial fluid samples were obtained before arthrocentesis on the first appointment and before the SH injection 15 days later. Nitrite and nitrate levels were measured with a highly sensitive and specific chemiluminescence detection method, and the concentration of lipid peroxidation products was assessed by means of the thiobarbituric acid reaction. RESULTS: Symptomatic improvement was seen in both groups. Nitrite, nitrate, and TBA-RS levels only decreased significantly (P <.05) with a supplemental SH injection after arthrocentesis. CONCLUSIONS: Intra-articular injections of SH may reduce nitrite, nitrate, and TBA-RS levels that play a role in the pathogenesis of various temporomandibular disorders.
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Adyuvantes Inmunológicos/administración & dosificación , Ácido Hialurónico/administración & dosificación , Nitratos/metabolismo , Nitritos/metabolismo , Paracentesis , Líquido Sinovial/metabolismo , Trastornos de la Articulación Temporomandibular/terapia , Articulación Temporomandibular/cirugía , Sustancias Reactivas al Ácido Tiobarbitúrico/metabolismo , Adolescente , Adulto , Terapia Combinada , Humanos , Inyecciones Intraarticulares , Persona de Mediana Edad , Líquido Sinovial/efectos de los fármacos , Trastornos de la Articulación Temporomandibular/metabolismo , Irrigación Terapéutica , Factores de TiempoRESUMEN
Oxygen free radicals have been suggested to be a contributory factor in diabetes complications. The aim of this study was to examine the effects of glyburide on the antioxidant enzyme activities in the heart tissue of diabetic rats. We investigated the activities of antioxidant enzymes (superoxide dismutase, catalase and glutathione peroxidase) in the hearts of both control and streptozotocin-induced diabetic rats. In the heart of diabetic rats, the activity of total superoxide dismutase decreased significantly (p < 0.005), whereas the activity of catalase and glutathione peroxidase increased to a large extent (p < 0.0001 and p = 0.05, respectively) at the end of the fourth week compared with the control group. Glyburide treatment of diabetic rats for 4 weeks corrected the changes observed in diabetic heart. In addition, blood glucose levels of untreated diabetic rats decreased following the glyburide treatment. These results demonstrate that the sulfonylurea glyburide is capable of exerting direct insulin-like effect on heart superoxide dismutase, catalase and glutathione peroxidase activities of diabetic rats in vivo.
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Catalasa/metabolismo , Diabetes Mellitus Experimental/tratamiento farmacológico , Glutatión Peroxidasa/metabolismo , Gliburida/uso terapéutico , Hipoglucemiantes/uso terapéutico , Miocardio/enzimología , Superóxido Dismutasa/metabolismo , Animales , Antioxidantes , Glucemia/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Diabetes Mellitus Experimental/enzimología , Masculino , Ratas , EstreptozocinaRESUMEN
The effectiveness and success of antituberculosis therapy is mainly measured by its ability to identify the organism in the sputum. In certain cases, available tuberculosis tests are not satisfactory and do not provide enough information on the effectiveness of antituberculosis therapy. Copper (Cu), zinc (Zn), and selenium (Se) are the essential elements that play a crucial role in the immune system. The serum levels of these elements vary in many diseases including tuberculosis. In this study, we investigate whether the serum levels of Cu, Zn, and Se change during antituberculosis therapy. We have included 22 pulmonary tuberculosis cases that were newly diagnosed with positive sputum and 18 healthy subjects. At the beginning and 2 mo after therapy, serum levels of Cu, Zn, and Se were measured by atomic absorption spectrometry. Despite Se and Cu levels not being affected during the treatment, we found that there was a significant increase in the levels of Zn and a decrease in the Cu/Zn ratio. Serum Zn levels and the Cu/Zn ratio could be used as a valuable laboratory tool for the clinicians to assess response to therapy or effectiveness of the ongoing antituberculosis therapy.
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Antituberculosos/uso terapéutico , Cobre/sangre , Selenio/sangre , Tuberculosis Pulmonar/sangre , Tuberculosis Pulmonar/tratamiento farmacológico , Zinc/sangre , Adolescente , Adulto , Anciano , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
Behçet's disease is a multisystemic disease characterized by activation and remission periods. The etiopathogenesis is not exactly known; a genetic defect in the immunoregulatory system induced by infectious agents, like viruses and bacteria, is thought to cause the disease. In this study, we examine the serum levels of vitamins A, C, and E, beta-carotene, selenium, and zinc in Behçet's disease patients and investigate the relationship between these serum levels and the activation of the disease. We conclude that adding vitamin E to the treatment of Behçet's disease patients and its effects on the prognosis of the disease need to be further investigated by controlled studies.
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Síndrome de Behçet/sangre , Selenio/sangre , Vitaminas/sangre , Zinc/sangre , beta Caroteno/sangre , Adulto , Estudios de Casos y Controles , Femenino , Humanos , MasculinoRESUMEN
Corneal photoablation with 193 nm argon fluoride excimer laser is a new technique for the treatment of refractive errors and for removing corneal opacities and irregularities. Ultraviolet radiation and thermal injury induce free radical formation in the tissues. The aim of this study was to confirm the production of free radicals by excimer laser photoablation in rabbits. The thermal changes of the posterior corneal surface were recorded during excimer laser photoablation. The lipid peroxide (LPO) levels and superoxide dismutase (SOD) activities of aqueous humour were measured after excimer laser keratectomy. The aqueous LPO levels were not changed after excimer laser ablation, but both the thermal increase in the cornea during the photoablation and the decreased aqueous SOD activities suggest that free radicals are formed in the cornea during excimer laser keratectomy, and that they may be responsible for some of the complications of excimer laser corneal surgery.
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Humor Acuoso/metabolismo , Córnea/cirugía , Peroxidación de Lípido , Peróxidos Lipídicos/metabolismo , Queratectomía Fotorrefractiva , Superóxido Dismutasa/metabolismo , Animales , Radicales Libres/metabolismo , Calor , Láseres de Excímeros , Conejos , Superóxidos/metabolismoRESUMEN
Measurement of alkaline phosphatase enzymatic activity is the most commonly used serum marker to assess bone formation. In this present study serum alkaline phosphatase, calcium, and phosphate were measured in 12 patients where natural coral was implanted in surgical bony defects. Blood samples were obtained preoperatively which served as control, and at 1, 7, 15, and 30 days. No statistically significant increase in serum alkaline phosphatase, calcium, and phosphate was observed.
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Fosfatasa Alcalina/sangre , Calcio/sangre , Cnidarios , Procedimientos Quirúrgicos Ortognáticos , Fosfatos/sangre , Prótesis e Implantes , Adolescente , Adulto , Animales , Femenino , Humanos , Neoplasias Maxilomandibulares/cirugía , Masculino , Mandíbula/cirugía , Persona de Mediana Edad , Tercer Molar/cirugía , Tumores Odontogénicos/cirugía , Osteogénesis , Quiste Radicular/cirugía , Diente Impactado/cirugíaRESUMEN
Ethyl pyruvate is a simple derivative in Ca(+2)- and K(+)-containing balanced salt solution of pyruvate to avoid the problems associated with the instability of pyruvate in solution. It has been shown to ameliorate the effects of ischemia-reperfusion (I/R) injury in many organs. It has also been shown that I/R injury delays the healing of colonic anastomosis. In this study, the effect of ethyl pyruvate on the healing of colon anastomosis and anastomotic strength after I/R injury was investigated. Anastomosis of the colon was performed in 32 adult male Wistar albino rats divided into 4 groups of 8 individuals: (1) sham-operated control group (group 1); (2) 30 minutes of intestinal I/R by superior mesenteric artery occlusion (group 2); (3) I/R+ ethyl pyruvate (group 3), ethyl pyruvate was administered as a 50-mg/kg/d single dose; and (4) I/R+ ethyl pyruvate (group 4), ethyl pyruvate administration was repeatedly (every 6 hours) at the same dose (50 mg/kg). On the fifth postoperative day, animals were killed. Perianastomotic tissue hydroxyproline contents and anastomotic bursting pressures were measured in all groups. When the anastomotic bursting pressures and tissue hydroxyproline contents were compared, it was found that they were decreased in group 2 when compared with groups 1, 3, and 4 (P < .05). Both anastomotic bursting pressure (P = .005) and hydroxyproline content (P < .001) levels were found to be significantly increased with ethyl pyruvate administration when compared with group 2. When ethyl pyruvate administration doses were compared, a significant difference was not observed (P > .05). Ethyl pyruvate significantly prevents the delaying effect of I/R injury on anastomotic strength and healing independent from doses of administration.
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Piruvatos/farmacología , Daño por Reperfusión/prevención & control , Cicatrización de Heridas/efectos de los fármacos , Anastomosis Quirúrgica , Animales , Relación Dosis-Respuesta a Droga , Masculino , Piruvatos/uso terapéutico , Ratas , Ratas WistarRESUMEN
We investigated the day-night differences in intestinal oxidative-injury and the inflammatory response following total body (TB) or abdominopelvic (AP) irradiation, and the influence of melatonin administration on tissue injury induced by radiation. Rats (male Wistar, weighing 220-280 g) in the irradiated groups were exposed to a dose of 8 Gy to the TB or AP region in the morning (resting period - 1 h after light onset) or evening (activity span - 13 h after light onset). Vehicle or melatonin was administered immediately before, immediately after and 24 h after irradiation (10, 2.0 and 10 mg/kg, ip, respectively) to the irradiated rats. AP (P < 0.05) and TB (P < 0.05) irradiation applied in the morning caused a significant increase in thiobarbituric acid reactive substance (TBARS) levels. Melatonin treatment in the morning (P < 0.05) or evening (P < 0.05) decreased TBARS levels after TB irradiation. After AP irradiation, melatonin treatment only in the morning caused a significant decrease in TBARS levels (P < 0.05). Although we have confirmed the development of inflammation after radiotherapy by histological findings, neither AP nor TB irradiation caused any marked changes in myeloperoxidase activity in the morning or evening. Our results indicate that oxidative damage is more prominent in rats receiving TB and AP irradiation in the morning and melatonin appears to have beneficial effects on oxidative damage irrespective of the time of administration. Increased neutrophil accumulation indicates that melatonin administration exerts a protective effect on AP irradiation-induced tissue oxidative injury, especially in the morning.
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Antioxidantes/uso terapéutico , Inflamación/prevención & control , Intestino Delgado/efectos de la radiación , Melatonina/uso terapéutico , Estrés Oxidativo , Protectores contra Radiación/uso terapéutico , Animales , Ritmo Circadiano , Masculino , Estrés Oxidativo/efectos de los fármacos , Estrés Oxidativo/efectos de la radiación , Traumatismos Experimentales por Radiación , Ratas , Ratas Wistar , Sustancias Reactivas al Ácido Tiobarbitúrico/metabolismo , Sustancias Reactivas al Ácido Tiobarbitúrico/efectos de la radiación , Irradiación Corporal TotalRESUMEN
Acute exercise may induce free-radical production in mitochondria during basal metabolism of aerobic cells. Ascorbic acid is a strong antioxidant agent, whereas myoglobin is known to act as an oxygen reservoir. The purpose of this study was to investigate the effects of acute exercise on malondialdehyde levels in gastrocnemius, vastus medialis, and triceps brachi muscles and erythrocytes. In addition, we investigated the ascorbic acid levels and serum myoglobin concentrations in rats, following acute swimming exercise. We found that the levels of muscle malondialdehyde and serum myoglobin increased and the levels of plasma ascorbic acid decreased, in proportion to the duration of exercise; however, the levels of erythrocyte malondialdehyde did not change.
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Ácido Ascórbico/sangre , Eritrocitos/metabolismo , Malondialdehído/metabolismo , Músculos/metabolismo , Mioglobina/sangre , Anafilaxis Cutánea Pasiva/fisiología , Animales , Peroxidación de Lípido/fisiología , Masculino , Ratas , Ratas Wistar , NataciónRESUMEN
1. Ornithine decarboxylase and Na-K ATPase activities were studied in rat livers that were treated with different doses of epidermal growth factor (EGF). 2. The ornithine decarboxylase activities were studied with spectrophotometry, and results were expressed as micromoles of putrescine per hour per milligram of protein. Na-K ATPase activities were studied on the basis of the principle of measuring the amount of inorganic phosphates released by the hydrolysis of ATP, and the results were expressed as micromoles of inorganic phosphate per hour per milligram of protein. 3. When compared with the controls, although the Na-K ATPase activities were decreased at low doses of EGF, their activities were found to be increased at high doses of EGF. On the other hand, there was a positive correlation between ornithine decarboxylase activities and EGF doses. 4. The results of this study suggest that, whereas the decrease in Na-K ATPase activities at low doses of EGF can be due to the utilization of the enzyme, the increase in Na-K ATPase activities at high doses of EGF can be attributed to its enhanced synthesis.
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Factor de Crecimiento Epidérmico/farmacología , Hígado/efectos de los fármacos , Ornitina Descarboxilasa/efectos de los fármacos , ATPasa Intercambiadora de Sodio-Potasio/efectos de los fármacos , Animales , Animales Recién Nacidos , Relación Dosis-Respuesta a Droga , Hígado/enzimología , RatasRESUMEN
Trimetazidine (TMZ), a potent antioxidant agent, has been used to protect the myocardium, liver and kidney from ischemia reperfusion (IR) injury. We investigated the effect of TMZ, a cellular anti-ischemic agent and a free radical scavenger, on 60 min of warm intestinal IR injury in rats. Sprague-Dawley rats were divided into three groups: a sham-operated group (no IR injury, n = 8), an ischemic control group (control, n = 8), and a TMZ-treated group (3 mg/kg, n = 8). Malondialdehyde (MDA) levels, myeloperoxidase (MPO) activity, and mucosal damage were investigated after 120 min of reperfusion. MDA levels and MPO activity were more elevated and histopathological damage more severe in the control group than in the sham group (P < 0.05). MDA levels and MPO activity were lower and there was less histopathological damage in the TMZ group than in the control group (P < 0.05). Accumulation of lipid peroxidation products and neutrophils in mucosal tissues were significantly inhibited by TMZ treatment. We conclude that pretreatment of rats with TMZ before intestinal ischemia attenuates but does not prevent, histological damage.