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1.
BMC Anesthesiol ; 23(1): 55, 2023 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-36797680

RESUMO

BACKGROUND: Pharmacogenetics could represent a further resource to understand the interindividual heterogeneity of response of the host to sepsis and to provide a personalized approach to the critical care patient. METHODS: Secondary analysis of data from the prospective observational study NCT02750163, in 50 adult septic and septic shock patients treated with Acetaminophen (ACT) for pyrexia. We investigated the presence of two polymorphisms, located respectively in the genes UGT1A1 and CYP3A5, that encode for proteins related to the hepatic metabolism of ACT. The main dependent variables explored were plasmatic concentration of ACT, body temperature and hepatic parameters. RESULTS: 8% of the patients carried CYP3A5 rs776746 A/G genotypes and showed significantly higher plasma levels of ACT than GG wild type patients, and than patients with UGT1A1 rs8330 C/G genotypes. CONCLUSIONS: Identifying specific genotypes of response to ACT may be helpful to guide a more personalized titration of therapy in sepsis and septic shock. CYP3A5 might be a good biomarker for ACT metabolism; however further studies are needed to confirm this result. TRIAL REGISTRATION: NCT02750163.


Assuntos
Sepse , Choque Séptico , Adulto , Humanos , Choque Séptico/tratamento farmacológico , Choque Séptico/genética , Acetaminofen/uso terapêutico , Farmacogenética , Citocromo P-450 CYP3A/genética , Sepse/tratamento farmacológico , Sepse/genética , Genótipo , Cuidados Críticos
2.
Prog Neurobiol ; 87(1): 58-79, 2009 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-18952141

RESUMO

In neurons, as in other excitable cells, mitochondria extrude Ca(2+) ions from their matrix in exchange with cytosolic Na(+) ions. This exchange is mediated by a specific transporter located in the inner mitochondrial membrane, the mitochondrial Na(+)/Ca(2+) exchanger (NCX(mito)). The stoichiometry of NCX(mito)-operated Na(+)/Ca(2+) exchange has been the subject of a long controversy, but evidence of an electrogenic 3 Na(+)/1 Ca(2+) exchange is increasing. Although the molecular identity of NCX(mito) is still undetermined, data obtained in our laboratory suggest that besides the long-sought and as yet unfound mitochondrial-specific NCX, the three isoforms of plasmamembrane NCX can contribute to NCX(mito) in neurons and astrocytes. NCX(mito) has a role in controlling neuronal Ca(2+) homeostasis and neuronal bioenergetics. Indeed, by cycling the Ca(2+) ions captured by mitochondria back to the cytosol, NCX(mito) determines a shoulder in neuronal [Ca(2+)](c) responses to neurotransmitters and depolarizing stimuli which may then outlast stimulus duration. This persistent NCX(mito)-dependent Ca(2+) release has a role in post-tetanic potentiation, a form of short-term synaptic plasticity. By controlling [Ca(2+)](m) NCX(mito) regulates the activity of the Ca(2+)-sensitive enzymes pyruvate-, alpha-ketoglutarate- and isocitrate-dehydrogenases and affects the activity of the respiratory chain. Convincing experimental evidence suggests that supraphysiological activation of NCX(mito) contributes to neuronal cell death in the ischemic brain and, in epileptic neurons coping with seizure-induced ion overload, reduces the ability to reestablish normal ionic homeostasis. These data suggest that NCX(mito) could represent an important target for the development of new neurological drugs.


Assuntos
Mitocôndrias/metabolismo , Doenças do Sistema Nervoso , Neurônios , Trocador de Sódio e Cálcio/metabolismo , Animais , Humanos , Modelos Biológicos , Doenças do Sistema Nervoso/etiologia , Doenças do Sistema Nervoso/metabolismo , Doenças do Sistema Nervoso/patologia , Neurônios/patologia , Neurônios/fisiologia , Neurônios/ultraestrutura , Trocador de Sódio e Cálcio/genética
3.
Int J Artif Organs ; 29(10): 1012-20, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17211823

RESUMO

Titanium is the most widely used material for dental implants. The natural formation, in presence of oxygen, of different oxide films (passivation films) is correlated to titanium implant biocompatibility, resistance to corrosion and is responsible for implant bacteriostatic action. Surface roughness is another surface property of Ti-implants that, affecting implant-to-bone contact, improves integration. In the present study data concerning composition, surface roughness and biocompatibility of Ghimas implants and mini-implants undergoing sandblasting with Calcium Magnesium Carbonate (CaMg(CO3)2) are reported. AFM, SEM/EDX, XRD analyses and morpho-functional tests (MTT and ALP) were performed. Cell actin cytoskeletal modification (fluorescence phalloidin staining) was also observed with confocal laser microscopy (CLSM). Data related to surface geometry and chemical properties, associated with evidence of high purity of all the tested materials (XRD and EDX), highlighted the elevated biocompatibility of tested implants and mini-implants. CLSM investigation confirmed osteoblast features of an active cell behavior able to fit cell to chemico-mechanical stimuli present at the bone/implant interface and suggests an effective implant/alveolar bone integration in vivo.


Assuntos
Materiais Biocompatíveis , Implantes Dentários , Titânio , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Faloidina , Coloração e Rotulagem , Difração de Raios X
4.
Cancer Res ; 58(4): 815-22, 1998 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-9485040

RESUMO

The human ether-a-go-go-related gene (herg) encodes a K+ current (IHERG) that plays a fundamental role in heart excitability by regulating the action potential repolarization (IKr); mutations of this gene are responsible for the chromosome 7-linked long QT syndrome (LQT2). In this report, we show that in a variety (n = 17) of tumor cell lines of different species (human and murine) and distinct histogenesis (neuroblastoma, rhabdomyosarcoma, adenocarcinoma, lung microcytoma, pituitary tumors, insulinoma beta-cells, and monoblastic leukemia), a novel K+ inward-rectifier current (IIR), which is biophysically and pharmacologically similar to IHERG, can be recorded with the patch-clamp technique. Northern blot experiments with a human herg cDNA probe revealed that both in human and murine clones the very high expression of herg transcripts can be quantified in at least three clearly identifiable bands, suggesting an alternative splicing of HERG mRNA. Moreover, we cloned a cDNA encoding for IIR from the SH-SY5Y human neuroblastoma. The sequence of this cDNA result was practically identical to that already reported for herg, indicating a high conservation of this gene in tumors. Consistently, the expression of this clone in Xenopus oocytes showed that the encoded K+ channel had substantially all of the biophysical and pharmacological properties of the native IIR described for tumor cells. In addition, in the tumor clones studied, IIR governs the resting potential, whereas it could not be detected either by the patch clamp or the Northern blot techniques in cells obtained from primary cell cultures of parental tissues (sensory neurons and myotubes), whose resting potential is controlled by the classical K+ anomalous rectifier current. This current substitution had a profound impact on the resting potential, which was markedly depolarized in tumors as compared with normal cells. These results suggest that IIR is normally only expressed during the early stages of cell differentiation frozen by neoplastic transformation, playing an important pathophysiological role in the regulatory mechanisms of neoplastic cell survival. In fact, because of its biophysical features, IIR, besides keeping the resting potential within the depolarized values required for unlimited tumor growth, could also appear suitable to afford a selective advantage in an ischemic environment.


Assuntos
Proteínas de Transporte de Cátions , Proteínas de Ligação a DNA , Neoplasias/genética , Canais de Potássio de Abertura Dependente da Tensão da Membrana , Canais de Potássio/genética , Transativadores , Sequência de Aminoácidos , Animais , Sequência de Bases , Fenômenos Biofísicos , Biofísica , Linhagem da Célula , Transformação Celular Neoplásica , Canal de Potássio ERG1 , Canais de Potássio Éter-A-Go-Go , Humanos , Camundongos , Dados de Sequência Molecular , Músculos/fisiologia , Neuroblastoma/genética , Neurônios/fisiologia , Regulador Transcricional ERG , Células Tumorais Cultivadas
5.
J Neurosci ; 20(10): 3915-25, 2000 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-10804231

RESUMO

Potassium homeostasis plays an important role in the control of neuronal excitability, and diminished buffering of extracellular K results in neuronal Hyperexcitability and abnormal synchronization. Astrocytes are the cellular elements primarily involved in this process. Potassium uptake into astrocytes occurs, at least in part, through voltage-dependent channels, but the exact mechanisms involved are not fully understood. Although most glial recordings reveal expression of inward rectifier currents (K(IR)), it is not clear how spatial buffering consisting of accumulation and release of potassium may be mediated by exclusively inward potassium fluxes. We hypothesized that a combination of inward and outward rectifiers cooperate in the process of spatial buffering. Given the pharmacological properties of potassium homeostasis (sensitivity to Cs(+)), members of the ether-a-go-go (ERG) channel family widely expressed in the nervous system could underlie part of the process. We used electrophysiological recordings and pharmacological manipulations to demonstrate the expression of ERG-type currents in cultured and in situ hippocampal astrocytes. Specific ERG blockers (dofetilide and E 4031) inhibited hyperpolarization- and depolarization-activated glial currents, and ERG blockade impaired clearance of extracellular potassium with little direct effect on hippocampal neuron excitability. Immunocytochemical analysis revealed ERG protein mostly confined to astrocytes; ERG immunoreactivity was absent in presynaptic and postsynaptic elements, but pronounced in glia surrounding the synaptic cleft. Oligodendroglia did not reveal ERG immunoreactivity. Intense immunoreactivity was also found in perivascular astrocytic end feet at the blood-brain barrier. cDNA amplification showed that cortical astrocytes selectively express HERG1, but not HERG2-3 genes. This study provides insight into a possible physiological role of hippocampal ERG channels and links activation of ERG to control of potassium homeostasis.


Assuntos
Astrócitos/química , Astrócitos/fisiologia , Proteínas de Transporte de Cátions , Canais de Potássio de Abertura Dependente da Tensão da Membrana , Canais de Potássio/análise , Canais de Potássio/genética , Animais , Antiarrítmicos/farmacologia , Astrócitos/ultraestrutura , Comunicação Celular/fisiologia , Césio/farmacologia , Relação Dose-Resposta a Droga , Eletrofisiologia , Epilepsia/fisiopatologia , Canais de Potássio Éter-A-Go-Go , Expressão Gênica/fisiologia , Coração/fisiologia , Hipocampo/citologia , Técnicas In Vitro , Síndrome do QT Longo/fisiopatologia , Masculino , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/fisiologia , Microscopia Eletrônica , Neurônios/citologia , Neurônios/fisiologia , Sondas de Oligonucleotídeos , Fenetilaminas/farmacologia , Piperidinas/farmacologia , Bloqueadores dos Canais de Potássio , Piridinas/farmacologia , RNA Mensageiro/análise , Ratos , Ratos Wistar , Medula Espinal/citologia , Sulfonamidas/farmacologia
6.
Transplantation ; 72(8): 1370-5, 2001 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-11685105

RESUMO

BACKGROUND: Pancreatic islet transplantation in diabetes, by restoring euglycemia, should in time correct the abnormal accumulation of advanced glycation end products (AGEs) over target tissues, thus delaying the development of late diabetic complications. METHODS: Homologous islet transplantation was performed in inbred Lewis rats 15 days (TA), 4 months (TB), and 8 months (TC) after streptozotocin diabetes. Group TA was studied for 12 months and groups TB and TC were studied for 4 months after transplantation. Normal (N) and diabetic (D) rats formed the control groups. Metabolic control in the transplant (T) groups was evaluated by oral glucose tolerance test. Blood glucose, glycated hemoglobin, and body weight were determined in all groups. AGE levels were determined by spectrofluorometry in eye lens proteins and by ELISA in aortic and tail tendon collagen. RESULTS: T groups showed normal oral glucose tolerance tests and metabolic parameters. The latter were altered in all D groups (P<0.005 to P<0.0001 versus N and T groups). AGEs were increased in the D groups (P<0.05 to P<0.001) versus the N groups. AGEs in the TA and TB groups were not different from those of the N groups but were significantly reduced (P<0.05 to P<0.001) when compared with those of the D groups. In the TC group, eye lens AGEs were significantly elevated (P<0.001) or significantly reduced (P<0.01) when compared with those of the N or D groups, respectively. Aortic collagen AGEs were elevated (P<0.01) by comparison with those of the N groups and not statistically different from those of the D groups. Tail tendon collagen AGE levels lay between those of the N and D groups, without reaching a statistical significance. CONCLUSIONS: These results indicate that primary and early secondary (groups TA and TB) but not late secondary (group TC) islet transplantations are capable of blocking or reducing an abnormal accumulation of AGEs, thus confirming the importance of preventive transplantation therapies.


Assuntos
Aorta/química , Diabetes Mellitus Experimental/terapia , Produtos Finais de Glicação Avançada/análise , Transplante das Ilhotas Pancreáticas , Cristalino/química , Tendões/química , Animais , Colágeno/análise , Diabetes Mellitus Experimental/metabolismo , Masculino , Ratos , Ratos Endogâmicos Lew , Estreptozocina , Cauda
7.
Transplantation ; 60(12): 1431-7, 1995 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-8545870

RESUMO

The early detection of allograft rejection remains elusive after solitary pancreas transplantation (PTX). We have previously described a modified technique of cystoscopic transduodenal PTX biopsy using the Biopty gun under ultrasound guidance. During the last 2 years, we performed 24 solitary PTXs with prospective protocol biopsy monitoring as well as biopsies performed whenever clinically indicated. The study group included 17 pancreas transplants alone, 6 sequential pancreas after kidney transplants, and 1 sequential pancreas after liver transplant. Five patients received pancreas retransplants. A total of 92 cystoscopically directed core PTX biopsies were performed, including 50 protocol biopsies (mean 2.1 per patient). Protocol biopsies were performed at 1 month (19), 2 months (3), 3 months (20), 6 months (7), and 12 months (1) after PTX. Adequate PTX tissue for histopathologic examination was obtained in 49 cases (98%). Biopsy findings included no rejection (34), mild rejection (13), pancreatitis (1), and cytomegalovirus infection (1). Overall, 15 of the 49 evaluable biopsies (31%) had significant histopathologic findings. All but 1 of the cases of mild rejection were treated with bolus steroids. Eight of these patients subsequently developed recurrent biopsy-proven rejection within 2 months; 5 grafts were subsequently lost to rejection between 3 and 13 months after PTX. Three biopsy complications occurred: 1 hematoma, 1 pancreatitis, and 1 ileus. Patient survival is 96% and PTX graft survival (complete insulin independence) is 75% after a mean follow-up of 15 months. In the remaining 42 clinically indicated biopsies, 3 were insufficient, 8 showed no rejection, and 31 (79%) had rejection. In half of these cases, the rejection was graded as moderate to severe. In conclusion, prospective monitoring with protocol PTX biopsies may result in the earlier detection of allograft rejection and have a direct effect on improving results after solitary PTX.


Assuntos
Rejeição de Enxerto/patologia , Transplante de Pâncreas/métodos , Adolescente , Adulto , Biópsia por Agulha/métodos , Criança , Humanos , Prognóstico , Estudos Prospectivos , Transplante Homólogo
8.
Br J Pharmacol ; 131(6): 1081-8, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11082114

RESUMO

1. Ventricular arrhythmias are rare but life-threatening side effects of therapy with the second-generation H(1) receptor antagonists terfenadine and astemizole. Blockade of the K(+) channels encoded by the Human Ether-à-go-go-Related Gene 1 (HERG1) K(+) channels, which is the molecular basis of the cardiac repolarizing current I(Kr), by prolonging cardiac repolarization, has been recognized as the mechanism underlying the cardiac toxicity of these compounds. 2. In the present study, the potential blocking ability of the novel second-generation H(1) receptor antagonist mizolastine of the HERG1 K(+) channels heterologously expressed in Xenopus oocytes and in HEK 293 cells or constitutively present in SH-SY5Y human neuroblastoma cells has been examined and compared to that of astemizole. 3. Mizolastine blocked HERG1 K(+) channels expressed in Xenopus oocytes with an estimated IC(50) of 3.4 microM. Mizolastine blockade was characterized by a fast dissociation rate when compared to that of astemizole; when fitted to a monoexponential function, the time constants for drug dissociation from the K(+) channel were 72.4+/-11.9 s for 3 microM mizolastine, and 1361+/-306 s for 1 microM astemizole. 4. In human embryonic kidney 293 cells (HEK 293 cells) stably transfected with HERG1 cDNA, extracellular application of mizolastine exerted a dose-related inhibitory action on I(HERG1), with an IC(50) of 350+/-76 nM. Furthermore, mizolastine dose-dependently inhibited HERG1 K(+) channels constitutively expressed in SH-SY5Y human neuroblastoma clonal cells. 5. The results of the present study suggest that the novel second-generation H(1) receptor antagonist mizolastine, in concentrations higher than those achieved in vivo during standard therapy, is able to block in some degree both constitutively and heterologously expressed HERG1 K(+) channels, and confirm the heterogeneity of molecules belonging to this therapeutical class with respect to their HERG1-inhibitory action.


Assuntos
Astemizol/farmacologia , Benzimidazóis/farmacologia , Proteínas de Transporte de Cátions , Proteínas de Ligação a DNA , Antagonistas dos Receptores Histamínicos H1/farmacologia , Canais de Potássio de Abertura Dependente da Tensão da Membrana , Canais de Potássio/efeitos dos fármacos , Transativadores , Animais , Linhagem Celular , Canal de Potássio ERG1 , Canais de Potássio Éter-A-Go-Go , Feminino , Humanos , Canais de Potássio/genética , Regulador Transcricional ERG , Xenopus
9.
Biochem Pharmacol ; 55(11): 1741-6, 1998 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-9714291

RESUMO

Electrophysiological and molecular biology techniques have widely expanded our knowledge of the diverse functions where K+ channels are implicated as potential and proven pharmacological targets. The aim of the present commentary is to review the recent progress in the understanding of the functional role of the K+ channels encoded by the human ether-a-gogo related gene (HERG), with particular emphasis on their direct pharmacological modulation by drugs, or on their regulation by pharmacologically relevant phenomena. About 3 years have passed since the cloning, expression, and description of the pathophysiological role of HERG K+ channels in human cardiac repolarization. Despite this short lapse of time, these K+ channels have already gained considerable attention as pharmacological targets. In fact, interference with HERG K+ channels seems to be the main mechanism explaining both the therapeutic actions of the class III antiarrhythmics and the potential cardiotoxicity of second-generation H1 receptor antagonists such as terfenadine and astemizole, as well as of psychotropic drugs such as some antidepressants and neuroleptics. It seems possible to anticipate that the main tasks for future investigation will be, on the one side, the better understanding of the intimate mechanism of action of HERG K+ channel-blocking drugs in order to elucidate the conditions regulating the delicate balance between antiarrhythmic and proarrhythmic potential and, on the other, to unravel the pathophysiological role of this K+ channel in the function of the brain and of other excitable tissues.


Assuntos
Antiarrítmicos/farmacologia , Proteínas de Transporte de Cátions , Proteínas de Ligação a DNA , Antagonistas dos Receptores Histamínicos H1/farmacologia , Canais de Potássio de Abertura Dependente da Tensão da Membrana , Canais de Potássio/efeitos dos fármacos , Transativadores , Animais , Antiarrítmicos/uso terapêutico , Sistema Nervoso Central/efeitos dos fármacos , Sistema Nervoso Central/metabolismo , Sistema Nervoso Central/fisiopatologia , Canal de Potássio ERG1 , Canais de Potássio Éter-A-Go-Go , Coração/efeitos dos fármacos , Coração/fisiopatologia , Antagonistas dos Receptores Histamínicos H1/uso terapêutico , Humanos , Miocárdio/metabolismo , Miocárdio/patologia , Estresse Oxidativo/efeitos dos fármacos , Canais de Potássio/genética , Canais de Potássio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Regulador Transcricional ERG
10.
Biochem Pharmacol ; 62(9): 1229-38, 2001 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-11705456

RESUMO

In the present study, the effect of the blockade of membrane calcium channels activated by intracellular Ca(2+) store depletion on basal and depolarization-induced [3H]norepinephrine ([3H]NE) release from SH-SY5Y human neuroblastoma cells was examined. The second-generation H(1) receptor blockers astemizole, terfenadine, and loratadine, as well as the first-generation compound hydroxyzine, inhibited [3H]NE release induced by high extracellular K(+) concentration ([K(+)](e)) depolarization in a concentration-dependent manner (the IC(50)s were 2.3, 1.7, 4.8, and 9.4 microM, respectively). In contrast, the more hydrophilic second-generation H(1) receptor blocker cetirizine was completely ineffective (0.1-30 microM). The inhibition of high [K(+)](e)-induced [3H]NE release by H(1) receptor blockers seems to be related to their ability to inhibit Ca(2+) channels activated by Ca(i)(2+) store depletion (SOCs). In fact, astemizole, terfenadine, loratadine, and hydroxyzine, but not cetirizine, displayed a dose-dependent inhibitory action on the increase in intracellular Ca(2+) concentrations ([Ca(2+)](i)) obtained with extracellular Ca(2+) reintroduction after Ca(i)(2+) store depletion with thapsigargin (1 microM), an inhibitor of the sarcoplasmic-endoplasmic reticulum calcium ATPase (SERCA) pump. The rank order of potency for SOC inhibition by these compounds closely correlated with their inhibitory properties on depolarization-induced [3H]NE release from SH-SY5Y human neuroblastoma cells. Nimodipine (1 microM) plus omega-conotoxin (100 nM) did not interfere with the present model for SOC activation. In addition, the inhibition of depolarization-induced [3H]NE release does not seem to be attributable to the blockade of the K(+) currents carried by the K(+) channels encoded by the human Ether-a-Gogo Related Gene (I(HERG)) by these antihistamines. In fact, whole-cell voltage-clamp experiments revealed that the IC(50) for astemizole-induced hERG blockade is about 300-fold lower than that for the inhibition of high K(+)-induced [3H]NE release. Furthermore, current-clamp experiments in SH-SY5Y cells showed that concentrations of astemizole (3 microM) which were effective in preventing depolarization-induced [3H]NE release were unable to interfere with the cell membrane potential under depolarizing conditions (100 mM [K(+)](e)), suggesting that hERG K(+) channels do not contribute to membrane potential control during exposure to elevated [K(+)](e). Collectively, the results of the present study suggest that, in SH-SY5Y human neuroblastoma cells, the inhibition of SOCs by some second-generation antihistamines can prevent depolarization-induced neurotransmitter release.


Assuntos
Canais de Cálcio/metabolismo , Proteínas de Transporte de Cátions , Proteínas de Ligação a DNA , Antagonistas dos Receptores Histamínicos H1/farmacologia , Norepinefrina/metabolismo , Canais de Potássio de Abertura Dependente da Tensão da Membrana , Receptores Histamínicos H1/metabolismo , Transativadores , Astemizol/farmacologia , Cálcio/metabolismo , Bloqueadores dos Canais de Cálcio/farmacologia , Canais de Cálcio/efeitos dos fármacos , Cetirizina/farmacologia , Canal de Potássio ERG1 , Canais de Potássio Éter-A-Go-Go , Humanos , Hidroxizina/farmacologia , Loratadina/farmacologia , Neuroblastoma , Canais de Potássio/metabolismo , Terfenadina/farmacologia , Regulador Transcricional ERG , Trítio , Células Tumorais Cultivadas
11.
Kidney Int Suppl ; 78: S230-3, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11169016

RESUMO

Homocysteine is regarded as a cardiovascular risk factor in both the general population and chronic renal failure patients. Among the mechanisms for homocysteine toxicity, its interference with transmethylation reactions, through its precursor/derivative S-adenosylhomocysteine, plays a multifarious role. In uremia, inhibition of S-adenosylmethionine methyl transfer reactions has been reported by independent investigators, using multiple approaches. This has several possible consequences, which can ultimately affect the patient's relative state of health.


Assuntos
Homocisteína/metabolismo , Uremia/metabolismo , Acilação , Aminoácidos/metabolismo , Doenças Cardiovasculares/etiologia , Humanos , Hiper-Homocisteinemia/complicações , Hiper-Homocisteinemia/epidemiologia , Metilação , Compostos Nitrosos/metabolismo , Oxirredução , Proteínas/metabolismo , Uremia/complicações
12.
Arch Surg ; 126(2): 149-56, 1991 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1992992

RESUMO

During a 50-month period, we identified 91 episodes of fungal infection in 72 liver transplant recipients (23.8%). Candida species accounted for 83.5% of cases. Clinical patterns of fungal infections included disseminated infection (19), peritonitis (17), pneumonitis (15), multiple sites of colonization (13), fungemia (11), and other sites (16). The diagnosis of fungal infection was usually made in the first 2 months (84.7% of cases), at a mean time of 16 days after transplantation. Risk factors for fungal infections included retransplantation, Risk score, intraoperative transfusion requirement, urgent status, Roux limb biliary reconstruction (in adults), steroid dose, bacterial infections and antibiotic therapy, and vascular complications. Fungal infections were successfully treated with amphotericin B in 63 cases (74.1%) but were associated with diminished patient survival (50% vs 83.5%). Fungal infection is a frequent source of early morbidity and can be related to well-defined risk factors, suggesting the need for effective prophylaxis.


Assuntos
Transplante de Fígado , Micoses/epidemiologia , Adolescente , Adulto , Idoso , Anfotericina B/uso terapêutico , Aspergilose/epidemiologia , Candidíase/epidemiologia , Criança , Pré-Escolar , Ciclosporinas/administração & dosagem , Feminino , Seguimentos , Humanos , Terapia de Imunossupressão , Incidência , Lactente , Recém-Nascido , Transplante de Fígado/efeitos adversos , Masculino , Pessoa de Meia-Idade , Micoses/tratamento farmacológico , Micoses/mortalidade , Micoses/fisiopatologia , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida
13.
J Am Coll Surg ; 184(3): 281-9, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9060926

RESUMO

BACKGROUND: Bladder drainage by the duodenal segment technique is currently the preferred method of handling the exocrine secretions after vascularized pancreatic transplantation. Despite improving results, however, the management of metabolic and urologic complications associated with bladder drainage remains problematic. STUDY DESIGN: A retrospective survey was performed of a consecutive case series of 196 pancreatic transplantations in 186 patients with diabetes over an 80-month period. All patients underwent whole organ pancreatic transplantation with bladder drainage by the duodenal segment technique. RESULTS: A total of 25 conversions (13 percent) from bladder drainage to enteric drainage were performed in 24 patients (24 side-to-side duodenoenterostomies, one Roux-en-Y limb duodenoenterostomy). The mean time of enteric conversion after pancreatic transplantation was 22 +/- 18 months (range, 1 to 72 months). All but two of the enteric conversions were performed at least 6 months after pancreatic transplantation. Indications for enteric conversion included dehydration with intractable metabolic acidosis (n = 18; 9 percent), urologic complications (n = 5; 3 percent), or problems with the duodenal segment (n = 2; 1 percent). The mean length of hospitalization for enteric conversion was 12 +/- 7 days (range, 6 to 30 days). All patients experienced improvement in their symptoms after enteric conversion. Anastomotic leaks developed postoperatively in five patients; two were managed operatively and three were managed nonoperatively. Oral bicarbonate supplementation was eliminated in all but one patient after enteric conversion. Patient survival is 100 percent and pancreatic graft survival (insulin independence) is 96 percent after a mean follow-up of 22 months after enteric conversion. CONCLUSIONS: Enteric conversion after pancreatic transplantation with bladder drainage is a safe and effective therapy for refractory problems related to the duodenal segment, altered physiologic function, or urologic complications and should be considered after 6 months for patients with persistent side effects.


Assuntos
Diabetes Mellitus Tipo 1/cirurgia , Drenagem , Transplante de Pâncreas/métodos , Complicações Pós-Operatórias , Bexiga Urinária/cirurgia , Adulto , Anastomose Cirúrgica , Duodeno/cirurgia , Humanos , Estudos Retrospectivos
14.
Eur J Surg Oncol ; 23(3): 211-4, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9236893

RESUMO

The ideal surgical approach for differentiated thyroid carcinomas (DTC) is a matter for debate. Total (TT) or near total (NT) thyroidectomy on one side, and lobectomy (LL) or lobo-isthmusectomy (LI) on the other side are the options. Extended (TT, NT) resections are preferable for several reasons, and LL or LI are preferred by some groups. Our 10-year experience indicates that the post-operative complications percentage may be low enough to make TT the preferred surgical option.


Assuntos
Complicações Pós-Operatórias/etiologia , Neoplasias da Glândula Tireoide/cirurgia , Tireoidectomia/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma/cirurgia , Distribuição de Qui-Quadrado , Feminino , Humanos , Incidência , Itália , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Neoplasias da Glândula Tireoide/patologia , Tireoidectomia/efeitos adversos , Resultado do Tratamento
15.
Physiol Behav ; 59(4-5): 729-33, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8778859

RESUMO

Despite the great interest of Cephalopods in learning studies, behavioral pharmacological experiments using these animals are scanty. The purpose of this study was to find an appropriate method of injection of substances for studying their effects on the behavior of octopuses. We injected into the branchial heart a known volume of seawater to test the effect of cold anaesthesia and of different types of manipulation on the predatory performance of Octopus vulgaris. An injection procedure that is simple, reliable, and does not require anaesthesia is proposed. The article also addresses ethical and manipulation requirements of modern behavioral pharmacology.


Assuntos
Comportamento Animal/efeitos dos fármacos , Manobra Psicológica , Octopodiformes/fisiologia , Anestesia , Animais , Temperatura Baixa , Feminino , Masculino , Modelos Psicológicos , Comportamento Predatório/efeitos dos fármacos , Água do Mar
16.
J Nephrol ; 12(4): 230-40, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10493566

RESUMO

Homocystinuria, an inherited disease in which plasma levels of homocysteine are high, was discovered in the sixties and it soon became clear that the affected patients had striking features of generalized atherosclerosis. The most common causes of death were arterial and venous thrombosis, stroke, or myocardial infarction. Observations in this human model of hyperhomocysteinemia led to studies in the general population whose findings suggest - though not conclusively- that homocysteine is a cardiovascular risk factor. The same is true for patients with chronic renal failure who almost always have moderate to severe high blood homocysteine levels. Homocysteine accumulates in relation to the concentration of its precursor, S-adenosylhomocysteine, a powerful competitive transmethylation inhibitor. Inhibition of a methyltransferase required to repair damaged proteins has actually been detected in uremic patients' red blood cells. However, in view of the multiple, widespread metabolic roles of S-adenosylmethionine-dependent methyltransferases, in many organs and tissues including the vascular endothelium, hypomethylation is currently interpreted as one of homocysteine's most important mechanisms of action. Various biological compounds, including small molecules and nucleic acids, as well as proteins, which are involved in the pathophysiology of thrombosis and atherosclerosis, are all potential targets of hypomethylation. Epidemiological studies and experimental models tend to confirm that homocysteine is both a cardiovascular risk factor and a uremic toxin, acting through different mechanisms.


Assuntos
Doenças Cardiovasculares/etiologia , Hiper-Homocisteinemia/complicações , Falência Renal Crônica/etiologia , Animais , Arteriosclerose/etiologia , Arteriosclerose/fisiopatologia , Homocisteína/fisiologia , Homocistinúria/complicações , Humanos , Hiper-Homocisteinemia/fisiopatologia , Hiper-Homocisteinemia/terapia , Falência Renal Crônica/fisiopatologia , Fatores de Risco
17.
Forensic Sci Int ; 146 Suppl: S55-6, 2004 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-15639588

RESUMO

Splenectomized patients are likely to suffer from severe infections, such as sepsis and meningitis. This syndrome is called overwhelming postsplenectomy infection (OPSI) in Europe and America. We present an adult case of OPSI syndrome, which occurred as respiratory insufficiency, and thrombocytopenia. The course is rapid, the clinical symptoms are serious, and the prognosis is very poor. Clinical examination showed cyanosis, mandibular hypertonia, psychomotor anxiety and purpura. Laboratory findings were thrombocytopenia, leukocytosis, hypoglycemia and altered coagulation parameters. A chest X-ray showed right pulmonary aspecific thickening. The autopsy findings occurred as Waterhouse-Friderichsen syndrome.


Assuntos
Coagulação Intravascular Disseminada/patologia , Esplenectomia/efeitos adversos , Síndrome de Waterhouse-Friderichsen/patologia , Dispneia/etiologia , Hemoptise/etiologia , Humanos , Hipoglicemia/etiologia , Pulmão/patologia , Masculino , Pessoa de Meia-Idade
18.
Forensic Sci Int ; 146 Suppl: S57-8, 2004 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-15639589

RESUMO

Isolated chloromas (granulocytic sarcomas) are rare tumours. Chloromas are masses composed of immature granulocytic cells. Granulocytic sarcoma occurs primarily in patients with acute myelogenous leukaemia, but can also arise in patients with other myeloproliferative disorders. We present an adult case of chloroma in HIV patient, which occurred as sudden death. Skin examination of right thigh showed dyschromia. Longitudinal incision of muscle revealed a "dark green" infiltration. Pathology showed in muscle fragments a infiltrate of granulocytes. The histologic sections of the excised tumour confirmed the cytologic diagnosis of chloroma.


Assuntos
Infecções por HIV/complicações , Sarcoma Mieloide/complicações , Adulto , Morte Súbita/etiologia , Humanos , Masculino , Músculo Esquelético/patologia
19.
J Pediatr Surg ; 27(12): 1557-9, 1992 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1469573

RESUMO

The authors describe a case of orthotopic liver transplantation (OLT) in a patient with an infantile form of choledochal cyst that progressed to severe hepatic failure. Choledochal cyst must be included in the differential diagnosis of extrahepatic biliary obstruction in infants; it represents an additional reason to consider early exploratory laparotomy, both for diagnosis and to perform definitive excision. In the event that end-stage liver disease develops, OLT should be considered.


Assuntos
Cisto do Colédoco/complicações , Falência Hepática/etiologia , Transplante de Fígado , Cisto do Colédoco/diagnóstico , Diagnóstico Diferencial , Feminino , Humanos , Lactente , Cirrose Hepática Biliar/etiologia , Falência Hepática/cirurgia
20.
J Cardiovasc Surg (Torino) ; 37(3): 229-35, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8698756

RESUMO

PURPOSE: To evaluate the effect of coenzyme Q10 in reducing the skeletal muscle reperfusion injury following clamping and declamping the abdominal aorta. METHODS: 30 patients undergoing elective vascular surgery for abdominal aortic aneurysm or obstructive aorto-iliac disease were randomly divided into two groups: patients in group I were treated with coenzyme Q10 (150 mg/day) for seven days before operation, and those in group II received a placebo. We studied the hemodynamic profile in each patient during clamping and declamping of the abdominal aorta. The plasma concentrations of thiobarbituric acid reactive substances (malondialdhehyde), conjugated dienes, creatine kinase and lactate dehydrogenase were measured in samples from both arterial and inferior vena cava sites. Serial sampling was performed after induction of anesthesia, 5 and 30 minutes after abdominal aortic cross clamping, 5 and 30 minutes after aortic cross-clamp removal. RESULTS: The concentrations of malondialdehyde, conjugated dienes, creatine kinase and lactate dehydrogenase in patients who received CoQ10 were significantly lower than in the placebo group. Decrease of plasma malondialdehyde concentrations correlated positively (p < 0.01) with decrease of both creatine kinase and lactate dehydrogenase release in samples from the inferior vena cava. The hemodynamic profile during clamping and declamping the abdominal aorta was similar in both groups. CONCLUSIONS: Our findings suggest that pre-treatment with coenzyme Q10 may play a protective role during routine vascular procedures requiring abdominal aortic cross clamping by attenuating the degree of peroxidative damage.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Doenças da Aorta/cirurgia , Arteriopatias Oclusivas/cirurgia , Músculo Esquelético/irrigação sanguínea , Traumatismo por Reperfusão/prevenção & controle , Ubiquinona/análogos & derivados , Coenzimas , Constrição , Método Duplo-Cego , Feminino , Hemodinâmica/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/metabolismo , Pré-Medicação , Traumatismo por Reperfusão/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Ubiquinona/uso terapêutico
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