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Biomedical subjects

A Secchi

Publications and source records attributed to A Secchi.

At least 55 records · Page 3Linked to original sources
PubMed1998

Improvement of glucose/insulin metabolism reduces hypertension in insulin-dependent diabetes mellitus recipients of kidney-pancreas transplantation.

There is increasing evidence that metabolic disorders are common in patients with hypertension. To evaluate the relationship between glucose/insulin metabolism and hypertension in diabetes, 61 hypertensive uremic insulin-dependent diabetes mellitus patients who were recipients of kidney or pancreas/kidney transplants were studied through a 1-year follow-up. Twenty of them received a kidney (K) transplant alone, 13 received a kidney and segmental pancreas (KSP), and 28 received a kidney and whole pancreas (KWP) with duodenocystostomy. All subjects received the same immunosuppressive treatment including steroids, azathioprine, and cyclosporine. The three groups of patients were comparable for biochemical parameters, clinical characteristic, cyclosporine levels, and renal function (creatinine < 2 mg/dl). The association between hypertension and type of transplant was evaluated according a global chi-square test, then the results were broken down into two components to test for differences in hypertension between KP versus K and KWP versus KSP groups. The improvement of hypertension rate was statistically associated with KP transplant the first week after surgery, at discharge, and 1 year after transplantation (hypertension% at 1 week: KWP = 75, KSP = 23 vs. K = 70, P = 0.004; at discharge: KWP = 39, KSP = 31 vs. K = 75, P = 0.017; at 1 yr: KWP = 44, KSP = 54 vs. K = 85, P = 0.02). One year after graft fasting, free immunoreactive insulin as well as glycosylated hemoglobin and glucose levels were statistically lower in the KP groups than in the K-alone recipients. The improvement of hypertension observed in KP recipients suggests a key role of glucose and insulin metabolism on pathogenesis of diabetic hypertension.

Adult↗
PubMed1998

Spontaneous hypoglycaemia after pancreas transplantation in Type 1 diabetes mellitus.

Hypoglycaemia is an important complication of insulin treatment in Type 1 diabetes mellitus (DM). Pancreas transplantation couples glucose sensing and insulin secretion, attaining a distinctive advantage over insulin treatment. We tested whether successful transplantation can avoid hypoglycaemia in Type 1 DM. Combined kidney and pancreas transplanted Type 1 DM who complied with good function criteria (KP-Tx, n = 55), and isolated kidney or liver transplanted non-diabetic subjects on the same immunosuppressive regimen (CON-Tx, n = 14), underwent 1-day metabolic profiles in the first 3 years after transplantation, sampling plasma glucose (PG) and pancreatic hormones every 2 hours. KP-Tx had lower PG than CON-Tx in the night and in the morning and higher insulin concentrations throughout the day. KP-Tx had lower PG nadirs than CON-Tx (4.40+/-0.05 vs 4.96+/-0.16 mmol l(-1), ANOVA p = 0.001). Nine per cent of KP-Tx had hypoglycaemic values (PG < or = 3.0 mmol l(-1)) in the profiles, both postprandial and postabsorptive, whereas none of CON-Tx did (p < 0.02). In conclusion, after pancreas transplantation, mild hypoglycaemia is frequent, although its clinical impact is limited. Compared to insulin treatment in Type 1 DM, pancreas transplantation improves but cannot eliminate hypoglycaemia.

Adult↗
PubMed1998

Measurement of blood flow in the main arteriole of the villi in rat small intestine with FITC-labeled erythrocytes.

Changes of blood flow in the intestine occur under various pathological conditions. The mucosa of the intestine is especially sensitive to tissue damage resulting in swelling, loss of tissue integrity, and ulceration. Changes of blood supply to the mucosa may contribute to local tissue damage. Therefore, the quantification of the perfusion of the intestinal mucosa in an animal model may help to elucidate the involved pathophysiological mechanisms. In our study, autologous erythrocytes were labeled with fluorescein-isothiocyanate and used for the evaluation of erythrocyte velocity in the main arteriole of the villi in the distal part of the ileum using intravital microscopy. In addition, the arteriolar diameter was determined, and the arteriolar blood flow was calculated. Under stable cardiovascular and respiratory conditions, blood flow ranged between 6.6 +/- 0.3 and 5.9 +/- 0.3 nl/min (means +/- SEM) during the observation period of 120 min. Our results suggest that this approach is a feasible method to quantify blood flow in the main arteriole of the villi and is therefore a suitable method for further investigating changes of mucosal blood flow in acute and chronic states of bowel disease.

Animals↗
PubMed1998

Mono-oligoclonal immunoglobulin abnormalities in diabetic patients after kidney transplantation: influence of simultaneous pancreas graft.

Monoclonal components (MC) are detected in as high as 30% of renal transplant recipients. Our aim was to evaluate the incidence, relevance and consequence of monoclonal components in patients with Type I (insulin-dependent) diabetes who received kidney (n = 22), kidney and whole pancreas (n = 41), kidney and segmental pancreas (n = 24) and kidney and islets (n = 12) transplants. Immuno-suppression was based on prophylactic anti-lymphocyte globulins, corticosteroids, azathioprine and cyclosporin in all patients; acute rejection was treated with steroids or anti-lymphocyte monoclonal immunoglobulin therapy (OKT3) or both. Serum immunofixation was carried out in all patients before transplantation and then after at 6 months and then yearly. Monoclonal components were detected in 81 of 99 patients (82%); 52 patients (52%) developed them within 6 months of transplantation, 15 (15%) between 6 and 12 months, with a peak prevalence at 1 year post-transplant (58%) and a decrease thereafter (10% at 9 years). Kidney recipients showed a lower incidence of monoclonal components when compared with those who received kidneys and segmental pancreases and those who received kidneys and whole pancreases. Monoclonal components were more often detected in patients who had previously experienced an acute renal rejection. Cytomegalovirus infection and acute rejection occurring in the same patient further increased the risk of developing monoclonal components, the development of which did not correlate with OKT3 treatment. A Post-transplant lymphoproliferative disorder was developed by two patients (2%), one with 5 and the other with 6 monoclonal components. In conclusion, diabetic patients receiving kidney and/or Pancreas transplantation, experiencing both cytomegalovirus infection and acute rejection, are at greatest risk of developing monoclonal components but they appear to be benign and transient; multiple band detection is a marker for the subsequent development of post-transplant lymphoproliferative disorder.

Adult↗
PubMed1997

Islet transplantation in IDDM patients.

This single-centre study investigated parameters that positively correlated with the success rate after islet allotransplantation in insulin-dependent diabetic (IDDM) patients. Twenty-one intrahepatic, fresh islet transplantations were performed in 20 IDDM patients (one patient had two transplants), after or simultaneous with kidney transplantation. The correlation between number and purity of transplanted islets and final outcome was investigated. One patient died of a cardiac arrest several hours after islet transplantation; this patient was not included in the follow-up analysis. Three patients (15%) experienced acute, irreversible, early failure of islet function, which was considered as a 'presumed rejection'. Nine patients (45%) achieved either complete insulin-independence (seven cases) or a reduction (> 50%) of exogenous insulin requirement (two cases), with sustained serum C-peptide secretion (0.89 +/- 0.04 nmol/l; duration: 21 +/- 7 months, range 2-58 months). Liver biopsy, performed 3 years after transplantation in one successful case, showed normal islets within the hepatic parenchyma. Eight cases (40%) did not show any metabolic effect of islet transplantation, with low serum C-peptide levels ('presumed function exhaustion'). Metabolic investigations performed in successful cases showed an early phase of insulin release after arginine, mild and reversible postprandial hyperglycaemia and normal HbA1c levels. Success of islet transplantation positively correlates with the number (p < 0.05) of the transplanted islets. Islet transplantation is a safe procedure, with 45% success rate, in terms of insulin-independence or relevant reductions of exogenous insulin requirement, although success can be transient.

Adult↗
PubMed1997

Amelioration of nerve conduction velocity following simultaneous kidney/pancreas transplantation is due to the glycaemic control provided by the pancreas.

Diabetic polyneuropathy is a common, disabling chronic complication of diabetes mellitus. Previous studies have suggested that combined pancreas-kidney transplantation can ameliorate nerve conduction. The relative contribution of the correction of hyperglycaemia and uraemia on nerve function is still a matter of debate. Nerve conduction velocity (NCV) was assessed before and after simultaneous pancreas and kidney transplantation, and before and after pancreas graft failure in five insulin-dependent diabetic (IDDM) patients affected by severe diabetic polyneuropathy. Sensory and motor NCV were recorded in five nerves and expressed as a cumulative index for each patient. Metabolic control was evaluated by fasting blood glucose and glycosylated haemoglobin levels. NCV index was below normal values before transplant: -3.8 +/- 0.7 (normal value: 0.89), improved 1 and 2 years after transplant: -3.1 +/- 1.3 and -2.6 +/- 0.9 (p = 0.0019), stabilised until pancreas failure and deteriorated to pre-transplant values 2 years after pancreas graft failure: -3.6 +/- 1.0 (p = 0.034). Fasting blood glucose levels worsened after pancreas graft failure. HbA1c levels, in the normal range during functioning pancreas graft (6.6 +/- 0.6%), deteriorated after its failure (8.0 +/- 0.6%, p = 0.04). Kidney function was preserved. These data support a positive effect of pancreas transplantation per se on NCV in IDDM subjects with diabetic polyneuropathy, thus demonstrating that metabolic control provided by a self-regulated source of insulin not only halts but also ameliorates nerve function, even if polyneuropathy is advanced.

Adult↗
PubMed1997

Dobutamine maintains intestinal villus blood flow during normotensive endotoxemia: an intravital microscopic study in the rat.

PURPOSE: The gut plays a pivotal role in sepsis. Intestinal hypoperfusion with subsequent ischemia leads to translocation of endotoxin. Dobutamine has been demonstrated to increase mesenteric blood flow during endotoxic shock; however, its effects on mucosal blood flow especially in intestinal villi is not known. Therefore, we investigated its influence on the blood flow and the arteriolar diameters in intestinal villi in a model of normotensive endotoxemia. MATERIALS AND METHODS: Twenty-one male Wistar rats were divided into three groups: (1) control, saline; (2) endotoxin, endotoxin 1.5 mg/kg during 60 minutes; and (3) dobutamine, endotoxin 1.5 mg/kg (60 minutes) and dobutamine 2.5 micrograms/kg/min during 120 minutes. Villus blood flow and arteriolar diameters were determined at 0 minutes, 60 minutes, and 120 minutes in each group using intravital microscopy. RESULTS: Villus blood flow was constant in the control group, significantly reduced at 120 minutes in the endotoxin group (120 minutes, 55.1 +/- 7.4%), and remained at baseline values in the dobutamine group. The arteriolar diameters remained constant in the control and the dobutamine groups, but they were significantly reduced in the endotoxin group at 120 minutes (7.8 +/- 0.2 to 6.5 +/- 0.7 micron). CONCLUSION: Our results indicate that in rats with normotensive endotoxemia, arteriolar diameters and blood flow in intestinal villi were reduced. Dobutamine prevented arteriolar constriction and maintained villus blood flow at preendotoxemic values.

Adrenergic beta-Agonists↗
PubMed1997

Personality traits and metabolic control: a study in insulin-dependent diabetes mellitus patients.

BACKGROUND: In the present study the authors evaluated the relationship between personality traits (according to DSM-III-R) and poor metabolic control in an adult onset insulin-dependent diabetes mellitus sample (n = 77). METHODS: Personality traits were assessed with the Personality Diagnostic Questionnaire--Revised. Metabolic control was evaluated through glycosilated hemoglobin (HbA1c): poor metabolic control was defined as HbA1c > or = 9% (normal values < 6.0%). RESULTS: Principal Component Analysis revealed three personality profiles: 'Cluster A/C Mixed', 'Cluster B Dependent' and 'Cluster B Aggressive'. Oneway ANCOVA, using sex as covariate, revealed a significant association (p = 0.01) only between poor metabolic control and Cluster B Dependent profile. No correlation was found between HbA1c and the other profiles. CONCLUSION: These data suggest that a specific personality profile is associated with poor metabolic control.

Adult↗
PubMed1997

Double-blind, randomised, placebo-controlled study of two concentrations of azelastine eye drops in seasonal allergic conjunctivitis or rhinoconjunctivitis.

This double-blind, randomised, placebo-controlled study was carried out to assess the efficacy and safety of 0.025% and 0.05% azelastine eye drops twice daily administered for 14 days to patients with seasonal allergic conjunctivitis or rhinoconjunctivitis. A total of 278 patients were recruited and 226 patients were evaluable for per protocol analysis. The target parameter was the response rate. Four eye symptoms, including the main symptom (itching) were recorded by patients in diaries and eight symptoms were assessed by physicians before and after seven and 14 days of treatment. Severity of symptoms was measured on a four-point scale. The response rates for itching (improvement of at least one score point within the first three days) according to patient assessment were 43% for placebo, 52% for 0.025% and 56% for 0.05% azelastine (NS). However, a more objective assessment of the three main eye symptoms by physicians showed a concentration-dependent improvement in response rate compared with placebo (a decrease of > or = 3 points from a baseline total score of > or = 6), which reached statistical significance for 0.05% azelastine on Day 7 (p < 0.002). In the evaluable patient population, the scores of the three main eye symptoms as well as of all eight recorded eye symptoms, as assessed by the physician, were significantly (p < 0.05) lower in the 0.05% azelastine eye drops group in comparison with the placebo group at Day 7. Inefficacy was the cause of withdrawal in five and three patients on 0.025% and 0.05% azelastine, respectively, and in six patients on placebo. Adverse drug effects, mainly a mild, transient irritation and a bitter or unpleasant taste, were reported by 14% (0.025%), 20% (0.05%) and 15% (placebo) of the patients. No serious side-effects occurred. Azelastine eye drops are effective and well tolerated at a concentration of 0.05% for the treatment of seasonal allergic conjunctivitis.

Adolescent↗
PubMed1997

Cancer arising after pancreas and/or kidney transplantation in a series of 99 diabetic patients.

OBJECTIVE: Recipients of solid organ transplants have an increased risk of developing certain types of malignancies as compared with the general population. The majority of the literature has reported on neoplasms in kidney and heart transplant recipients. RESEARCH DESIGN AND METHODS: We describe 9 neoplasms occurring in 7 out of 73 IDDM patients after simultaneous pancreas and kidney transplantation. No cases were recorded among 26 IDDM recipients of kidney transplantation. RESULTS: Among the neoplasms found were 2 cases of posttransplant lymphoproliferative disorder (PTLD), malignant melanoma, basal-cell and squamous-cell carcinoma of the skin in the same patient, squamous-cell carcinoma in situ of the vulva, hepatocarcinoma, small-cell lung cancer, and ductal carcinoma of the breast. Four patients died. Among immunological risk factors, over-immunosuppression for steroid-resistant kidney rejection was administered only in the 2 cases of PTLD. CONCLUSIONS: Increased dosage of immunosuppressive agents may be necessary in some patients of prevent or treat rejection in view of their reduced survival on hemodialysis.

Adult↗
PubMed1996

Metabolic effects of successful intraportal islet transplantation in insulin-dependent diabetes mellitus.

The intraportal injection of human pancreatic islets has been indicated as a possible alternative to the pancreas transplant in insulin-dependent diabetic patients. Aim of the present work was to study the effect of intraportal injection of purified human islets on: (a) the basal hepatic glucose production; (b) the whole body glucose homeostasis and insulin action; and (c) the regulation of insulin secretion in insulin-dependent diabetes mellitus patients bearing a kidney transplant. 15 recipients of purified islets from cadaver donors (intraportal injection) were studied by means of the infusion of labeled glucose to quantify the hepatic glucose production. Islet transplanted patients were subdivided in two groups based on graft function and underwent: (a) a 120-min euglycemic insulin infusion (1 mU/kg/min) to assess insulin action; (b) a 120-min glucose infusion (+75 mg/di) to study the pattern of insulin secretion. Seven patients with chronic uveitis on the same immunosuppressive therapy as grafted patients, twelve healthy volunteers, and seven insulin-dependent diabetic patients with combined pancreas and kidney transplantation were also studied as control groups. Islet transplanted patients have: (a) a higher basal hepatic glucose production (HGP: 5.1 +/- 1.4 mg/kg/ min; P < 0.05 with respect to all other groups) if without graft function, and a normal HGP (2.4 +/- 0.2 mg/kg/min) with a functioning graft; (b) a defective tissue glucose disposal (3.9 +/- 0.5 mg/kg/min in patients without islet function and 5.3 +/- 0.4 mg/kg/min in patients with islet function) with respect to normals (P < 0.01 for both comparisons); (c) a blunted first phase insulin peak and a similar second phase secretion with respect to controls. In conclusion, in spite of the persistence of an abnormal pattern of insulin secretion, successful intraportal islet graft normalizes the basal HGP and improves total tissue glucose disposal in insulin-dependent diabetes mellitus.

Adult↗
PubMed1996

Effect of endotoxemia on intestinal villus microcirculation in rats.

Intestinal mucosal hypoperfusion with subsequent ischemia during endotoxemia might cause a breakdown of the gut barrier with translocation of bacteria and their toxins into the systemic circulation, thus maintaining a "gut-derived" septic state. The aim of this study was to investigate the influence of endotoxin on the microcirculation of intestinal villi, which represent the most vulnerable part of the mucosa. The changes in blood flow and in the diameters of the central villus arterioles located in the distal ileum were monitored in control rats without lipopolysaccharide (LPS) exposure (n=7), and in rats receiving 1.5 mg/kg b.w. LPS (n=7) or 15 mg/kg b.w. LPS (n=7) over 60 min. The blood flow and the arteriolar diameters were determined using in vivo videomicroscopy at baseline, and 60 min and 120 min later. In control animals, no change in blood flow and arteriolar diameters were observed during the entire experiment. Administration of 1.5 mg/kg b.w. LPS reduced the blood flow to 69.5 +/- 9.0% of the baseline value at the end of the study period. This decrease in blood flow was associated with a decrease in the villus arteriolar diameters by 17.4 +/- 2.5% from the baseline values. In animals exposed to 15 mg/kg b.w. LPS, the decrease in villus blood flow at 60 min was 64.8 +/- 10.9% of baseline, and at 120 min 66.9 +/- 12.6% of baseline. The diameters of the villus arterioles were reduced by 11.5 +/- 2.4% and 15.1 +/- 1.7%, respectively. In the control group and in the 1.5-mg/kg LPS group, the mean arterial blood pressure did not change during the entire study period. In the 15-mg/kg LPS group, the mean arterial pressure tended to decrease after 60 min. These data suggest a reduction of villus blood flow due to vasoconstriction in the central villus arterioles during normotensive endotoxmia, which might represent the mechanism for the mucosal ischemia observed in critically ill patients.

Animals↗