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101.
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Two patients from two separate families were diagnosed as having type IIB von Willebrand disease, because they had lifelong bleeding tendencies, prolonged bleeding times, no large von Willebrand factor multimers, and low levels of ristocetin cofactor in plasma with heightened ristocetin-induced platelet aggregation. There was no history of bleeding, and no laboratory abnormalities were found in the parents and sibship of either propositi, in contrast with the autosomal dominant pattern of inheritance usually observed in type IIB von Willebrand disease. Abnormalities of ristocetin-induced von Willebrand factor-platelet interactions were less severe than in a patient from a previously reported family with type IIB von Willebrand disease studied in parallel. The peculiar features of these cases provide additional evidence of the existence of heterogeneity within this variant.  相似文献   
104.
Summary Alteration in insulin secretion and reduced peripheral sensitivity to the hormone have been reported in type II diabetes. In this paper, a comparison is made of basal glucose production (3H-6 glucose), insulin secretion and insulin sensitivityin vivo (hyperglycemic clamp) andin vitro (binding to circulating monocytes) in 24 patients with recently diagnosed type II diabetes, matched for age and fasting glycemia and divided into non-obese (14 subjects) and moderately obese (10 subjects), and in 9 non-obese controls. The non-obese diabetics were slightly hyperinsulinemic during fasting (10.8±1.0vs 4.8±0.8 μU/ml in controls, p < 0.0005), with a significant reduction in early and late insulin secretion (14.0±1.5vs 20.8 ± 2.0 μU/ml, p<0.01 and 24.8±3.3vs 34.7±2.14 μU/ml, p<0.025). The insulin sensitivity index MCR/I was significantly reduced (2.30±0.32vs 4.14±0.40, p<0.005). Endogenous glucose production was significantly increased (107±10.2vs 84±3.7 mg/m2 per min, p<0.025) and displayed a positive correlation with fasting glycemia (r=0.51, p<0.05). Insulin binding to monocytes was significantly lower than in controls (2.36±0.22%vs 4.06±0.32%, p<0.0005). Moderately obese diabetics also were significantly hyperinsulinemic in the fasting state (18.1±2.8 μU/ml, p<0.0005vs controls) but, typically, lacked the early secretory phase (20.6±3.6 μU/mlvs baseline, n.s.). A similar increase of hepatic glucose production (107±11.2 mg/m2 per min, p<0.025vs controls, n.s.vs non-obese diabetics) and decrease of peripheral sensitivity to insulin (MCR/I=1.78±0.31, p<0.0005vs controls, n.s.vs non-obese diabetics) was found in moderately obsese diabetics, as well as a significant reduction of insulin binding to insolated monocytes (2.62±0.4% p<0.01vs controls, n.s.vs non-obese diabetics). These results confirm that common defects of both non-obese and moderately obese type II diabetics are: lack of early phase of glucose induced insulin secretion, increase in hepatic glucose production and decrease of peripheral insulin sensitivity together with reduction of insulin binding to circulating monocytes. The hypothesis of a unique defect as a cause of hyperglycemia in type II diabetes in early clinical phase is not borne out by the results of this study. Moderate obesity, even if able to reduce insulin sensitivity, seems to be less important in determining hyperglycemia. This study was supported by a grant fromConsiglio Nazionale delle Ricerche, P.F. Medicina Preventiva, SP4,Malattie Degenerative, N. 84.02449.56.  相似文献   
105.
OBJECTIVE: Acquired hypopituitarism in adults is obviously suspected in patients with primary hypothalamic-pituitary diseases, particularly after neurosurgery and/or radiotherapy. That brain injuries (BI) can cause hypopituitarism is commonly stated and has been recently emphasized but the management of BI patients does not routinely include neuroendocrine evaluations. AIM: To clarify the occurrence of hypopituitarism in patients after traumatic brain injury (TBI) or subarachnoid haemorrhage (SAH) 3 months after the BI. SUBJECTS AND METHODS: The occurrence of hypopituitarism in conscious patients after traumatic brain injury [TBI, n = 100, 31 women, 69 men; age 37.1 +/- 1.8 years; body mass index (BMI) 23.7 +/- 0.4 kg/m(2); Glasgow Coma Scale (GCS) 3-15] or subarachnoid haemorrhage [SAH, n = 40, 14 men, 26 wpmen, 51.0 +/- 2.0 years; 25.0 +/- 0.6 kg/m(2); Fisher's scale 1-4] was studied in a multicentre study 3 months after the BI. All patients underwent wide basal hormonal evaluation; the GH/IGF-I axis was evaluated by GHRH + arginine test and IGF-I measurement. RESULTS: In TBI patients, some degree of hypopituitarism was shown in 35%. Total, multiple and isolated deficits were present in 4, 6 and 25%, respectively. Diabetes insipidus was present in 4%. Secondary adrenal, thyroid and gonadal deficit was present in 8, 5 and 17%, respectively. Severe GH deficiency (GHD) was the most frequent pituitary defect (25%). In SAH patients, some degree of hypopituitarism was shown in 37.5%. Despite no total hypopituitarism, multiple and isolated deficits were present in 10 and 27.5%, respectively. Diabetes insipidus was present in 7.5%. Secondary adrenal, thyroid and gonadal deficit was present in 2.5, 7.5 and 12.5%, respectively. Severe GHD was the most frequent defect (25%). CONCLUSIONS: TBI and SAH are conditions associated with high risk of acquired hypopituitarism. The pituitary defect is often multiple and severe GHD is the most frequent defect. Thus neuroendocrine evaluations are always mandatory in patients after brain injuries.  相似文献   
106.
The immunocytochemical detection of multidrug-resistance (MDR) associated P-glycoprotein (P-170) was longitudinally performed on bone marrow smears from 32 responsive patients with acute leukaemia in the different phases of the disease (at diagnosis, in complete remission, at relapse) by means of APAAP technique and monoclonal antibody C219. The whole group of eight patients with presence of P-170 positive cells while in complete remission rapidly relapsed with a high proportion of blasts showing MDR phenotype; they were resistant to further treatments. Twelve out of 24 subjects without cells with MDR phenotype in complete remission remained in this condition, six had a responsive relapse (without significant expression of P-170 in 5/6 patients) and six a resistant relapse. Four patients of this last group significantly expressed P-170. Our data indicate that the detection of scattered P-170 positive cells during complete remission might identify a subset of leukaemic patients with high risk of early and resistant relapse.  相似文献   
107.
The aim of this study was to evaluate the efficacy of a 6-month treatment with lanreotide (LAN) (60–90 mg/month) alone and combined with cabergoline (CAB) (1.5-3 mg/week) in 10 acromegalic patients previously demonstrated to be poor responders to octreotide (OCT) (0.6 mg/day) alone and combined with quinagolide (CV) (0.6 mg/day).All patients had previously undergone unsuccessful surgery and none of them received radiotherapy. Immunohistochemistry showed intense positive GH staining in all adenomas, positive PRL staining in 5 adenomas and faint ACTH or FSH/LH positive staining in other 2 adenomas. Moderately elevated serum PRL levels (35 and 47 ng/ml) were recorded in two patients. Fasting plasma IGF-I and serum GH levels were assayed at baseline and 30, 60, 90 and 120 days after each treatment. Gallbladder ultrasonography and sellar MRI were performed before and after 6 months of OCT and LAN treatments.After OCT treatment circulating GH and IGF-I levels remained elevated in all patients, while after 3 months of combined OCT+CV treatment, serum GH levels were suppressed (below 2.5 ng/ml) in only 1 patient. Significant increase of the percent GH (83.9±4.3 vs. 70.3±5.6%, p<0.01) and IGF-I suppression (54±4.4 vs. 45.3±5.7, p<0.01) and decrease of the nadir of GH (8.5±1.2 vs. 14.6±1.9 ng/ml, p<0.01) and IGF-I (400.9±32.8 vs. 462.1±45.1 ng/ml) were obtained with the combined treatment when compared to OCT treatment alone. After a 15–30 days wash-out, circulating GH and IGF-I levels significantly increased up to pretreatment level in all patients. After 6 months of treatment with LAN, suppression of serum GH was achieved in 1 patient, but no difference in GH (66.3±6.3%) and IGF-I (43.9±4.6%) suppression was recorded in comparison to OCT treatment. After 3 months of treatment with LAN combined with CAB, suppression of serum GH and normalization of plasma IGF-I levels was achieved in 4 and 5 patients, respectively. Percent suppression of GH (88.1±2.1%) and IGF-I (57.5±2.8%) was significantly greater with the combined treatment than with LAN treatment alone. In the 7 patients with evident residual mass no change was documented by magnetic resonance imaging (MRI). None of the patients withdrew LAN+CAB treatment for poor tolerance, one patient had mild hypotension. Sludge was shown after 6 months of LAN treatment in one patient without notable change after 3 months of LAN+CAB treatment.In conclusion, the treatment with dopaminergic drugs such as CV and CAB, significantly increased the efficacy of somatostatin analogs, and can be used in combined therapy in poorly responsive patients.  相似文献   
108.
The prostate is a target organ of the GH and IGF-I axis because prostate hypertrophy is found in acromegaly, reduced prostate size is found in GH deficiency (GHD) patients, and additionally, IGF-I is reported to be a positive predictor factor of prostate cancer. To investigate whether GH replacement therapy in adult patients with GHD has adverse effects on the prostate, we studied the effect of 12-month GH or GH plus testosterone replacement on prostate pathophysiology in 24 adult patients with GHD (11 euandrogenemic and 13 hypoandrogenemic), compared with 24 age-matched healthy controls. At study entry, GHD patients had lower prostate volume than controls (19.4 +/- 1.7 vs. 24.9 +/- 1.7 ml; P = 0.03). After 12 months of treatment, all hypoandrogenemic patients achieved normal testosterone levels, and prostate volume increased in the patients to the same level as controls (25.0 +/- 1.9 ml). The percentage increase in prostate volume was greater in hypoandrogenemic patients receiving both GH and testosterone replacement (51 +/- 11%) than in those receiving GH replacement alone (15 +/- 3%; P < 0.0009). At baseline, prostate volume was similar in GHD patients below or above 60 yr of age (16.8 +/- 1.3 vs. 23 +/- 3.6 ml; P = 0.08), whereas after treatment it was higher in the latter patients (21.8 +/- 1.2 vs. 29.5 +/- 3.9 ml; P = 0.04). Prostate-specific antigen (PSA) and free PSA did not change, whereas PSA density was significantly reduced after treatment in hypoandrogenemic patients; there was also no change in calcifications, cysts, or nodules. In conclusion, GH replacement restores prostate size to normal in both young and elderly patients, with no increase in prostate abnormalities. Because the simultaneous treatment with GH and testosterone induces an increase of prostate size by 50% of baseline on average, care is suggested in elderly patients with prostate hyperplasia to avoid any risk of prostate symptoms. In these cases, GH replacement might be performed sequentially to reduce the hypertrophic effect of combining GH and testosterone.  相似文献   
109.
More than 20 DNA mutations with different inheritance pattern have been described in patients with Bernard-Soulier Syndrome (BSS), leading to abnormal or absent synthesis and/or expression of GPIbalpha. Clinical phenotype shows considerable variation between individuals, such as bleeding, platelet count and the percentage of large platelets. We describe in a BSS patient the first case of homozygous four bases deletion (TGAG) in the gpIbalpha gene coding sequence, leading to a premature stop codon. In the propositus, blood smears revealed giant platelets (30 x 10(9) platelets/L), and platelet agglutination to ristocetin was absent. Propositus' parents are consanguineous. His father and paternal grandmother showed a mild thrombocytopenia (108 x 10(9)/L and 120 x 10(9)/L platelets respectively) while mothers and sister's referred normal platelet counts. The surface expression of GPIbalpha was practically undetectable by flow-cytometry and western blot in the patient and was reduced in the father. Proband's DNA analysis revealed a homozygous four-base-pair deletion (TGAG), starting from the last base of the codon for Ser39, leading to a coding frame shift with a new termination codon after 11 novel amino acids. The same mutation was seen in heterozygosis in both parents. This is the first report of GPIbalpha TGAG deletion in homozygous state even if the defect has already been described in a case of compound heterozygosis. Surprisingly, the propositus does not report any spontaneous bleeding tendency.  相似文献   
110.
Cardiovascular disease is claimed to be one of the most severe complications of acromegaly, contributing significantly to mortality in this disease. In fact, an excess of growth hormone (GH) and insulin-like growth factor 1 (IGF-I) causes a specific derangement of cardiomyocytes, leading to abnormalities in cardiac muscle structure and function, inducing a specific cardiomyopathy. In the early phase of acromegaly the excess of GH and IGF-I induces a hyperkinetic syndrome, characterized by increased heart rate and increased systolic output. Concentric hypertrophy is the most common feature of cardiac involvement in acromegaly, found in more than two thirds of patients at diagnosis. This abnormality is commonly associated with diastolic dysfunction and eventually with impaired systolic function ending in heart failure, if the GH/IGF-I excess is left untreated. In addition, abnormalities of cardiac rhythm and of heart valves have also been described in acromegaly. The coexistence of other complications, such as arterial hypertension and diabetes mellitus, aggravates acromegalic cardiomyopathy. Successful control of acromegaly induces a decrease in left ventricular mass and an improvement in diastolic function, while the effects of GH/IGF-I suppression on systolic function are more variable. However, since cardiovascular alterations in young patients with short disease duration are milder than in those with longer disease duration, it is likely to be easier to reverse and/or arrest acromegalic cardiomyopathy in young patients with early-onset disease. In conclusion, careful assessments of cardiac function, morphology, and activity are required in patients with acromegaly. An early diagnosis and prompt effective treatment are important in order to reverse acromegalic cardiomyopathy.  相似文献   
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