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1.
Musculoskelet Surg ; 106(4): 469-474, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34342873

RESUMO

PURPOSE: To assess the complications and second surgeries rates at 1 year follow-up in a group of patients underwent minimally invasive fixation with screws or hybrid external fixation (HEF) for tibial plateau fractures (TPF). The hypothesis was that low Schatzker (I-IV) TPF would have shown a lower complication rate with respect to high Schatzker (V-VI) TPF. METHODS: 148 patients who underwent minimally invasive surgery with screws or HEF for TPF were included and pooled in two groups: mono-condylar (Schatzker I-IV) and bi-condylar (Schatzker V-VI). The rate of second surgeries and complications, such as stiffness, infection, wound dehiscence and malunion occurred within 1 year, were reported. RESULTS: Statistically significant difference between mono-condylar and bi-condylar groups was found in terms of stiffness (18% vs. 37%, p = 0.01), malunion (4% vs 21%, p = 0.004) and second surgeries (32% vs. 48%, p = 0.049). Associated procedures performed during TPF fixation increased risk of second surgeries (OR 2.1, p < 0.001). No differences in terms of second surgeries and complications were found in bi-condylar group treated with screws and HEF. CONCLUSION: Bi-condylar TPF treated with minimally invasive surgery developed a significantly higher rates of stiffness, malunion and second surgeries within 1 year compared to mono-condylar fractures. Moreover, when an associated procedure was performed, the risk of a reoperation was nearly doubled. Trial registration number PG 0012506 CE AVEC 620/2018/Oss/IOR.


Assuntos
Fixação de Fratura , Fraturas da Tíbia , Humanos , Fixação de Fratura/métodos , Fixadores Externos , Fraturas da Tíbia/cirurgia , Fraturas da Tíbia/etiologia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Procedimentos Cirúrgicos Minimamente Invasivos/efeitos adversos , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Fixação Interna de Fraturas/efeitos adversos , Fixação Interna de Fraturas/métodos
2.
Musculoskelet Surg ; 105(2): 173-181, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31993972

RESUMO

PURPOSE: The purpose of this study was to compare two types of posterior-stabilized (PS) mobile-bearing (MB) total knee arthroplasties (TKAs). The hypothesis was that no major differences were going to be found among the two TKA designs. METHODS: Two cohorts of patients who were divided according to implant design (Cohort A, new design gradually reducing radius PS MB TKA; Cohort B, traditional dual-radius PS MB TKA) were analyzed by means of intraoperative navigation. All operations were guided by a non-image-based navigation system that recorded relative femoral and tibial positions in native and implanted knees during the following kinematic tests: passive range of motion (PROM), varus-valgus stress test at 0° and 30° (VV0, VV30) and anterior/posterior drawer test at 90° of flexion (AP90). RESULTS: There were no significative differences in kinematic tests between the two implants. Cohort A, however, showed a different post-implant trend for VV0 and VV30 that were lower than the pre-implant ones, as expected, while for Cohort B, the trend is opposite. However, the gradually reducing radius prosthesis (Cohort A) showed a trend of improving stability (29% compared to the preoperative status) in mid-flexion (VV30) which the traditional dual-radius design (Cohort B) would not. Moreover, we found no differences among postoperative results of the two TKA designs. CONCLUSION: Despite design variations, no difference has been found among the prostheses in terms of PROM, rotations and translations. Both design kinematics did not show paradoxical external rotations, but an increase in femoral translation in mid-flexion without affecting the functioning of the prosthesis. LEVEL OF EVIDENCE: II.


Assuntos
Artroplastia do Joelho , Prótese do Joelho , Fenômenos Biomecânicos , Humanos , Articulação do Joelho/cirurgia , Desenho de Prótese , Amplitude de Movimento Articular
3.
Musculoskelet Surg ; 105(3): 235-246, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33315156

RESUMO

Loosening is considered as a main cause of implant failure in total knee replacement (TKR). Among the predictive signs of loosening, migration is the most investigated quantitative parameter. Several studies focused on the migration of the tibial component in TKR, while no reviews have been focused on the migration of the femoral component and its influence on patients' clinical outcomes. The aim of this narrative review was (1) to provide information about of the influence of migration in femoral component of TKR prostheses, (2) to assess how migration may affect patient clinical outcomes and (3) to present alternative solution to the standard cobalt-chrome prostheses. A database search was performed on PubMed Central® according to the PRISMA guidelines for studies about Cobalt-Chrome femoral component migration in people that underwent primary TKR published until May 2020. Overall, 18 articles matched the selection criteria and were included in the study. Few studies investigated the femoral component through the migration, and no clear migration causes emerged. The Roentgen Stereophotogrammetric Analysis has been mostly used to assess the migration for prognostic predictions. An annual migration of 0.10 mm seems compatible with good long-term performance and good clinical and functional outcomes. An alternative solution to cobalt-chrome prostheses is represented by femoral component in PEEK material, although no clinical evaluations have been carried out on humans yet. Further studies are needed to investigate the migration of the femoral component in relation to clinical outcomes and material used.


Assuntos
Artroplastia do Joelho , Prótese do Joelho , Ligas de Cromo , Humanos , Prótese do Joelho/efeitos adversos , Desenho de Prótese , Falha de Prótese , Tíbia
5.
Ann Ital Chir ; 76(1): 31-7, 2005.
Artigo em Italiano | MEDLINE | ID: mdl-16035669

RESUMO

Repairing a parietal defect of a large incisional hernia should not be limited to the closure of the breach by means of the modern biocompatible prosthetic sheets, but must also be able to restore a correct intra abdominal pressure, otherwise the derangement from the normal respiratory dynamics and the circulatory stasis in the abdominal veins and in those of the lower limbs remain unaltered. Over-correcting the parietal abdominal tension on the contrary can cause a dangerous compartmental syndrome. The attempts of an intraoperative measurement of the correct intra abdominal pressure restoration has been generally hampered from the condition of curarization of the patient during the operation. Using the automatic mechanical ventilator fixed at volume and not at pressure priority, as usual, can offer the possibility to calibrate, following objective parameters, the propriety of the surgical repair still during the final phases of the reparative operation. The simplicity and ingenuity of the here proposed method and the normal availability in every operative theatre of the necessary means for this measurements described, requires attention among the surgeons and a large diffusions of its simple use.


Assuntos
Hérnia Ventral/cirurgia , Monitorização Fisiológica/métodos , Procedimentos de Cirurgia Plástica , Telas Cirúrgicas , Idoso , Idoso de 80 Anos ou mais , Síndromes Compartimentais/prevenção & controle , Seguimentos , Hérnia Ventral/fisiopatologia , Humanos , Pessoa de Meia-Idade , Monitorização Fisiológica/instrumentação , Pressão
6.
Ann Ital Chir ; 75(1): 59-62, 2004.
Artigo em Italiano | MEDLINE | ID: mdl-15283389

RESUMO

The Argon Beam Coagulator has gained his space in surgery thanks to its operative characteristics, that are very useful in sealing the bleeding parenchymal tissue with minimal injury to the surroundings. The aim of the present study is that of evaluate the physical properties of the instrument in its coagulation action. The experimental study with the Birtcher 6000 Argon Beam Coagulator has been designed to measure the top temperature that develops right where the Argon beam meets the tissue, while operating. Using a laser guided telethermometer, the searching of that temperature was uneasy right on the operatory field because of the unwilling movements of the operator hand and those of the patient himself. Therefore a similar protocol was made on a piece of meat coming from the butcher. At the longest application of the beam coagulation on the same point the developed temperature was never higher than 100 degrees C whilst a complete coagulation effects. The advantage of the Argon Beam coagulation are therefore to seal the diffuse bleeding without injury to this adjacent tissues, never exposed to a temperature higher than that of boiling water. The advantages are also evident in comparison with the more usual spray electrosurgery that is instead characterized by a wide carbonisation also with this spray option.


Assuntos
Argônio , Perda Sanguínea Cirúrgica/prevenção & controle , Hemostasia Cirúrgica/métodos , Instrumentos Cirúrgicos , Animais , Bovinos , Temperatura Alta , Carne
7.
G Ital Nefrol ; 20(6): 606-10, 2003.
Artigo em Italiano | MEDLINE | ID: mdl-14732913

RESUMO

BACKGROUND: HCV infection in hemodialysis is still a matter of debate from an epidemiological and clinical point of view. Evaluation criteria for HCV-infected patients as transplant candidates are still not adequately standardized. Aims of the present study were to investigate: 1. the percentage of HCV positive patients on the waiting list of three Italian regions belonging to the Associazione InterRegionale Trapianti (AIRT); 2. to analyze the clinical approach in the evaluation of these patients in the attempt to define national guidelines for their pre- and post-transplant management. PATIENTS: We evaluated 2045 uremic patients on the waiting lists of four transplant centers (Bari, Bologna, Modena, Novara) belonging to AIRT at 31/12/2002. RESULTS: The overall prevalence of HCV positive patients was 14.2%, with a peak in the Puglia waiting list. The most common screening tests were AST and ALT serum levels and viral load (HCV RNA). Although there is a clear evidence that histological parameters are the main diagnostic and prognostic markers, a liver biopsy was performed in only 9.5% of patients. An even smaller percentage of HCV-infected patients underwent anti-viral therapy. CONCLUSIONS: Our retrospective analysis evidenced the need to improve common clinical strategies in approaching HCV-infected canditates to renal transplantation in the attempt to improve their post-transplant outcome.


Assuntos
Hepatite C/epidemiologia , Transplante de Rim , Adulto , Idoso , Algoritmos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Listas de Espera
8.
G Ital Nefrol ; 20(6): 611-4, 2003.
Artigo em Italiano | MEDLINE | ID: mdl-14732914

RESUMO

BACKGROUND: In transplanted patients undergoing immunossuppressive therapy the incidence of malignant neoplasia is 3-4 times higher than in the general population. Aim of the present study was to evaluate the prevalence of different tumours and the links between modulation of immunosuppressive therapy and patient and graft survival. PATIENTS: We evaluated 2029 kidney-transplanted patients from four Transplant Centres (Bari, Bologna, Modena, Novara) belonging to the Associazione InterRegionale Trapianti (AIRT). RESULTS: The incidence of neoplastic disease after transplantation was 3.9% in our population with a median time between transplantation and clinical onset of 23 months. We demonstrated a significant difference in the geographical distribution of different tumours. We did not observe any correlation with specific immunosuppressive drugs. Finally, dramatic reduction of the immunosuppression levels did not modify either the patients' or the graft's survival. CONCLUSIONS: Several factors can influence the post-transplant onset of neoplastic diseases with immunosuppressive therapy playing a pivotal role. The implementation of a National Registry would be the first step in an attempt to optimise immunosuppression in this particular group of patient's.


Assuntos
Transplante de Rim/efeitos adversos , Neoplasias/etiologia , Humanos , Incidência , Pessoa de Meia-Idade , Neoplasias/epidemiologia , Prevalência , Estudos Retrospectivos
9.
G Ital Nefrol ; 19(4): 446-50, 2002.
Artigo em Italiano | MEDLINE | ID: mdl-12369048

RESUMO

BACKGROUND: Proteinuria is associated with an increased risk of renal failure. In chronic kidney transplant failure it is associated with poorer graft outcome. MATERIALS AND METHODS: In our Unit 405 renal transplants were performed between April 1992 and December 2001. We analysed 1) the main causes of post-transplant proteinuria and 2) the prognostic significance for graft outcome in patients with a minimum follow-up of 6 months. RESULTS: Early proteinuria was associated with a higher incidence of chronic allograft nephropathy (CAN) and de novo/recurrent nephropathies. Graft outcome was poorer in patients with early persistent proteinuria. CONCLUSIONS: Proteinuria after renal transplantation increases the risk of graft failure. We can, therefore, hypothesize that a graft biopsy is the best way to reveal the causes of proteinuria so that therapeutic interventions, which have been shown to reduce proteinuria, can be applied immediately.


Assuntos
Rejeição de Enxerto/urina , Transplante de Rim , Complicações Pós-Operatórias/epidemiologia , Proteinúria/epidemiologia , Adulto , Biópsia , Feminino , Rejeição de Enxerto/epidemiologia , Humanos , Incidência , Itália , Testes de Função Renal , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Prognóstico , Estudos Retrospectivos , Coleta de Tecidos e Órgãos , Transplante/patologia , Resultado do Tratamento
10.
G Ital Nefrol ; 19(3): 316-25, 2002.
Artigo em Italiano | MEDLINE | ID: mdl-12195400

RESUMO

Over the last few years emerging evidence indicate the involvement of herpes viruses in the pathogenesis of several medical complications in transplanted patients. Herpes viruses are transmitted via inter-human contact and cause a primary infection, which commonly fails to give clinical signs and may persist even for years in a latent state in healthy subjects. In transplanted patients, herpes viruses may be transmitted through the transplanted organ or may be reactivated because of the use of powerful immunosuppressive drugs. Moreover, the persistence of immunosuppression greatly favours the clinical expression and severity of virus infection. Thus, herpes viruses seem to be involved in both acute and chronic deterioration of graft function, in the pathogenesis of post-transplant lymphoproliferative disorders and Kaposi sarcoma, and even in vessel atherosclerosis. This review will focus on relevant clinical aspects of herpes-virus infection, namely cytomegalovirus, EBV, herpes simplex 1 and 2, varicella zoster virus, HHV-6, HHV-7 and HHV-8, in kidney transplanted patients.


Assuntos
Infecções por Herpesviridae/etiologia , Transplante de Rim/efeitos adversos , Infecções por Citomegalovirus/etiologia , Infecções por Vírus Epstein-Barr/etiologia , Humanos
11.
Transplantation ; 64(6): 913-8, 1997 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-9326420

RESUMO

BACKGROUND: Recent data indicate that factors other than erythropoietin (EPO), such as insulin-like growth factor 1 (IGF-1), can promote erythropoiesis in vitro and correct the anemia of chronic renal failure in vivo. IGF-1 is produced by the liver under growth hormone control, as well as by other sources, including the kidney. The erythropoietic role of growth factors and cytokines and their possible modulation by angiotensin-converting enzyme inhibitors (ACEI) has never been explored. METHODS: This study evaluated the serum levels of EPO, IGF-1, interleukin (IL)-2, IL-3, and granulocyte macrophage-colony-stimulating factor in 40 kidney transplanted patients with or without posttransplant erythrocytosis (PTE) and in 10 living kidney donors. Then, the effect of ACEI therapy on the above pattern was examined in patients with PTE. RESULTS: EPO and IGF-1 serum levels were significantly higher in patients with PTE than in patients without PTE and in living kidney donor subjects. ACEI therapy significantly reduced hematocrit (Hct) as well as circulating IGF-1 and EPO levels. Of note, the decrease in IGF-1 was prominent mainly in those patients whose EPO levels were not significantly modified by ACEI therapy. In all of the patients Hct levels displayed a direct relationship with circulating IGF-1 levels, but not with EPO concentration. Growth hormone did not significantly differ among the groups examined, whereas it steeply increased under ACEI. Finally, no significant difference in IL-2, IL-3, and granulocyte macrophage-colony-stimulating factor serum levels was detected. CONCLUSIONS: IGF-1 seems to play a role in the ACEI-related decrease of Hct in patients with PTE, chiefly in patients without any modification of EPO serum levels.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/efeitos adversos , Eritropoese/efeitos dos fármacos , Eritropoetina/sangue , Hematócrito , Transplante de Rim/fisiologia , Doadores de Tecidos , Adulto , Análise de Variância , Creatinina/sangue , Contagem de Eritrócitos , Feminino , Fator Estimulador de Colônias de Granulócitos e Macrófagos/sangue , Hemoglobinas/análise , Humanos , Fator de Crescimento Insulin-Like I/análise , Interleucina-2/sangue , Interleucina-3/sangue , Transplante de Rim/imunologia , Contagem de Leucócitos , Masculino , Contagem de Plaquetas , Policitemia , Análise de Regressão
12.
Nephrol Dial Transplant ; 12(12): 2687-93, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9430873

RESUMO

BACKGROUND: Despite marked improvements in the success of solid organ transplantation, a significant percentage of transplanted organs is lost due to recurrent episodes of acute cellular rejection. The mechanisms that govern allograft rejection likely include a complex regulatory network of multiple cytokines and growth factors. DESIGN AND METHOD: This study investigated the kidney gene (in situ hybridization) and protein (immunohistochemistry) expression and the urinary excretion rate of IL-6 and EGF in 29 renal transplant recipients: 16 with acute cellular rejection (AR) and 13 with acute tubular damage/cyclosporine toxicity (ATD). RESULTS: AR patients displayed a 4-fold increase of renal IL-6 expression, which localized chiefly to proximal tubular cells and monocytes/macrophages, whereas EGF signal was extremely weak or even absent. In ATD patients, EGF expression was markedly reduced, while IL-6 specific signal was unchanged. In all the patients examined the renal expression of IL-6 and EGF strictly correlated with their urinary excretion rate (r:0.459, P:0.001). Thus, urinary IL-6/EGF ratio was markedly increased in the former group (> 20-fold at day 1), where it paralleled the modifications of plasma creatinine over time (r:0.603, P < 0.0001), and was only slightly increased in the latter group (< 3-fold). CONCLUSION: Kidney transplanted patients with acute cellular rejection or acute tubular damage/CyA nephrotoxicity exhibit a distinctly different pattern of intragraft expression of IL-6 and EGF, which is closely reflected by their rate of urinary excretion.


Assuntos
Ciclosporina/intoxicação , Fator de Crescimento Epidérmico/metabolismo , Rejeição de Enxerto/metabolismo , Imunossupressores/intoxicação , Interleucina-6/metabolismo , Rim/metabolismo , Doença Aguda , Adolescente , Adulto , Fator de Crescimento Epidérmico/genética , Fator de Crescimento Epidérmico/urina , Feminino , Expressão Gênica/fisiologia , Rejeição de Enxerto/urina , Humanos , Interleucina-6/genética , Interleucina-6/urina , Rim/efeitos dos fármacos , Rim/fisiopatologia , Masculino , Pessoa de Meia-Idade
13.
Kidney Int ; 49(3): 656-65, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8648906

RESUMO

The kidney is one of the major sites of EGF production and there it seems to play several biological functions, such as modulation of cell growth, renal repair following injury, regulation of cellular metabolism and glomerular haemodinamics. The present study was first aimed at localizing EGF and its receptor (R) in normal human kidney by immunohistochemical and in situ hybridization techniques. Then, the distribution of the growth factor and its R was explored in biopsy specimens from eight patients with acute tubulointerstitial damage. In the normal human kidney, both EGF immunoreactivity and EGF mRNA were localized in tubular profiles corresponding to Henle's loop and, although to a lesser intensity, to distal convoluted tubule. EGF immunostaining was remarkable mainly at the apical surface of tubular cells. EGF-R protein expression was detected in glomerular endothelial cells, in peritubular capillaries and arteriolar walls, as well as along the thick ascending limb of Henle's lop and distal convoluted tubule, where it colocalized with Tamm-Horsfall protein. Immunohistochemical analysis of tubular profiles revealed that EGF-R was located especially along the basolateral membrane of tubular cells and within the basal part of cytoplasm. Endogenous alkaline phosphatase and CHIP28 positive tubules did not show any signal for EGF and its receptor. Kidneys with acute tubulointerstitial injury exhibited a dramatic decrease of EGF expression, whereas EGF-R showed only minor modifications. Interestingly, EGF-R was localized to both apical and antiluminal membranes of positive tubular cells. It is concluded that EGF-EGF receptor loop may be relevant in the pathogenesis of acute tubulointerstitial damage and recovery from tubular injury, while its role in the physiological renewal of the urothelium remains speculative.


Assuntos
Carcinoma/metabolismo , Fator de Crescimento Epidérmico/metabolismo , Receptores ErbB/metabolismo , Neoplasias Renais/metabolismo , Rim/metabolismo , Biópsia , Carcinoma/patologia , Fator de Crescimento Epidérmico/genética , Receptores ErbB/genética , Humanos , Imuno-Histoquímica , Hibridização In Situ , Rim/patologia , Neoplasias Renais/patologia , RNA Mensageiro/metabolismo
14.
Thromb Haemost ; 74(6): 1516-20, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8772230

RESUMO

Cultured human mesangial cells (HMC) derived from normal kidneys have been shown to synthesize tissue-type plasminogen activator (t-PA) and excess amounts of PA inhibitor type 1 (PAI-1). Conflicting results have been obtained concerning the production of urokinase-type PA (u-PA) and efforts to show PA inhibitor 2 (PAI-2) met with failure. We evaluated the fibrinolytic profile of cultured HMC lines obtained from 12 patients with renal carcinoma and one cadaveric kidney donor. Subconfluent cells (third passage) were incubated overnight in serum-free medium. t-PA, u-PA, PAI-1 and PAI-2 antigens were assayed by ELISA methods and PA and PAI activities by amidolytic methods both in conditioned medium (CM) and cell extracts (CE). Besides PAI-1, PAI-2 antigen was detected in all but one HMC lines. At variance with the former, which was largely released in the culture medium, PAI-2 was mainly cell-associated. t-PA antigen was found in all but two cell lines while u-PA antigen was detected in relatively high concentrations in 8 cell lines. PA activity, identified as u-PA by functional and immunological criteria, was measured in CM of six of the eight u-PA producing cell lines, whereas PAI activity was undetectable or very low in CM of all cell lines, suggesting that PAI-1 was largely inactive. Functional assays of cell extracts demonstrated the presence of PA activity, again identified as u-PA, only in samples (five lines) containing u-PA antigen in excess over PAI-2. PAI activity was found instead in the extracts in which the inhibitor was higher than the activator (six lines) and was identified as PAI-2, as it inhibited u-PA but not single-chain t-PA and was neutralized by a polyclonal anti-PAI-2 antibody. The heterogeneous fibrinolytic pattern of HMC lines was confirmed by mRNA analysis of three representative lines. Results were similar when HMC lines at passage five were used, except that the u-PA content was significantly reduced both in CM and CE. These findings indicate that the fibrinolytic profile of cultured HMC is more complex than previously reported. The production of large amounts of PAI-2 may represent an additional control mechanism of proteinase activity.


Assuntos
Fibrinólise/fisiologia , Mesângio Glomerular/metabolismo , Inibidor 1 de Ativador de Plasminogênio/biossíntese , Inibidor 2 de Ativador de Plasminogênio/biossíntese , Northern Blotting , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Estudos de Avaliação como Assunto , Mesângio Glomerular/citologia , Humanos
15.
Acta Endocrinol (Copenh) ; 122(4): 450-4, 1990 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2159203

RESUMO

The effect of D-(-)-beta-hydroxybutyrate, at concentrations commonly achieved during ketoacidosis in humans (10 mmol/l), on human fat cell lipolysis in vitro was the aim of this study. The basal lipolysis was not modified and beta-hydroxybutyrate did not affect forskolin- or dibutyryl-cAMP-stimulated glycerol release, whereas it markedly inhibited isoproterenol-stimulated lipolysis. In membranes of intact adipocytes exposed to D-(-)-beta-hydroxybutyrate for 1 h, we found a decrease in beta-adrenoceptor affinity in saturation experiments and a shift to the right of the isoproterenol-mediated radioligand [( 125I]-cyanopindolol) displacement curve. These findings suggest that beta-hydroxybutyrate inhibits catecholamine-stimulated lipolysis by decreasing beta-adrenoceptor affinity. No effect of beta-hydroxybutyrate was found on beta-adrenoceptor binding of intact mononuclear cells of peripheral blood. In conclusion, the beta-adrenoceptor affinity lowering effect of beta-hydroxybutyrate is seemingly specific to human fat cells and might represent a feed-back mechanism that prevents an uncontrolled breakdown of triglycerides and indirectly regulates its own production rate.


Assuntos
Tecido Adiposo/efeitos dos fármacos , Hidroxibutiratos/farmacologia , Corpos Cetônicos/farmacologia , Leucócitos Mononucleares/efeitos dos fármacos , Lipólise/efeitos dos fármacos , Receptores Adrenérgicos beta/efeitos dos fármacos , Ácido 3-Hidroxibutírico , Tecido Adiposo/metabolismo , Adulto , Bucladesina/antagonistas & inibidores , Colforsina/antagonistas & inibidores , Retroalimentação , Humanos , Técnicas In Vitro , Isoproterenol/antagonistas & inibidores , Leucócitos Mononucleares/metabolismo , Masculino , Pessoa de Meia-Idade
16.
Diabete Metab ; 15(6): 409-15, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2560726

RESUMO

Catecholamines acutely exert a pronounced insulin-antagonistic effect, which is mediated by beta-adrenergic receptors stimulation. Nevertheless, several patients with pheochromocytoma fail to exhibit an overt diabetic syndrome, in spite of steadily elevated plasma levels of catecholamines. This prompted us to investigate a 16 years old male patient, bearing an extra-adrenal pheochromocytoma, who displayed a slightly impaired glucose tolerance to oral glucose tolerance test, whereas fasting and post-prandial blood glucose, as well as glycaemic response to intravenous glucagon, were in the normal range. Peripheral insulin sensitivity, as evaluated by intravenous insulin tolerance test, was slightly decreased. Supine norepinephrine plasma levels were steadily upon 9 ng/ml; plasma insulin, both fasting and post-prandial, was within the normal range. beta-adrenergic receptors density of peripheral mononuclear cells was strongly reduced when compared to controls (0.97 +/- 0.08 vs 2.82 +/- 0.37 fmol/10(6) cells), without any concomitant change of affinity. Insulin binding to circulating monocytes was reduced as well (2.38 +/- 0.27 vs 5.1 +/- 0.4%/10(7) monocytes); insulin receptor affinity was quite normal (1.7 ng/ml) and total receptor number was 9,200 sites/cell. In desensitization experiments, 1 microM isoproterenol caused only a 20% decrease of beta-adrenergic receptors density in the patient's cells (70% decrease in controls). Six months after surgery, all the above modifications of receptor binding, as well as the mild glucose intolerance, were almost completely reversed. Thus, high levels of norepinephrine were able to induce a decrease of both beta-adrenoceptor and insulin receptor binding, together with a marked reduction of in vitro agonist-induced redistribution of beta-adrenergic receptors.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Neoplasias das Glândulas Suprarrenais/fisiopatologia , Catecolaminas/sangue , Resistência à Insulina , Isoproterenol/farmacologia , Monócitos/metabolismo , Feocromocitoma/fisiopatologia , Receptor de Insulina/metabolismo , Receptores Adrenérgicos beta/metabolismo , Adolescente , Neoplasias das Glândulas Suprarrenais/sangue , Neoplasias das Glândulas Suprarrenais/cirurgia , Adulto , Glicemia/análise , Seguimentos , Teste de Tolerância a Glucose , Humanos , Técnicas In Vitro , Insulina/sangue , Masculino , Feocromocitoma/sangue , Feocromocitoma/cirurgia , Receptores Adrenérgicos beta/efeitos dos fármacos , Valores de Referência
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