Comparison of ß2-microglobulin serum level between Alzheimer's patients, cognitive healthy and mild cognitive impaired individuals.

BACKGROUND: Several studies performed in the last years on the brain, showed that beta2-microglobulin (ß2m) and MHC can act independently of their canonical immune function to regulate normal brain development, synaptic plasticity and behaviour. Increased systemic levels of soluble ß2m have been implicated in cognitive impairments like that associated with chronic haemodialysis, or aortic valve replacement. Increased soluble ß2m has also been detected in the cerebral spinal fluid (CSF) of patients with HIV-associated dementia and Alzheimer's disease (AD). OBJECTIVE: To compare plasma ß2m levels in healthy subjects and subjects with dementia or cognitive impairment. METHODS: We measured the concentration of ß2m in a cohort of 245 individuals and compared sex matched, cognitive healthy individuals. RESULTS: We found higher levels of ß2m in AD patients compared to non-AD MCI and healthy controls (2063 ng/mL ±852 versus 1613 ± 503 and 1832 ± 382 ng/mL, p< 0.001 and <0.033, respectively), while there was no difference between mild cognitive impairment (MCI) and healthy controls (p > 0.05). CONCLUSIONS: Our data confirm that ß2m could play a role in AD. However, a replication study in an independent cohort would be necessary to confirm our preliminary results.

High-Dose and High-Frequency Lanreotide Autogel in Acromegaly: A Randomized, Multicenter Study.

Context: Increase in drug frequency or dose is recommended for acromegaly patients with partial response to long-acting somatostatin receptor ligands (SRLs). However, the efficacy and safety data with lanreotide (LAN) Autogel (LAN-ATG) at high dose (HD) or high frequency (HF) are still scanty. Objective: To evaluate the biochemical efficacy and safety of HF and HD LAN-ATG in patients with active acromegaly. Design: Twenty-four-week prospective, multicenter, randomized, open-label trial. Patients and Interventions: Thirty patients with active acromegaly, partial responders to SRLs, were randomized to HF (120 mg/21 days; 15 patients) or HD (180 mg/28 days; 15 patients) LAN-ATG. Outcomes: Normalization of serum insulin-like growth factor-I (IGF-I) and reduction in random growth hormone (GH) values < 1.0 µg/L, reduction in serum IGF-I and GH from baseline, differences in biochemical response between HF and HD LAN-ATG, adverse events. Results: IGF-I decreased significantly (P = 0.007) during the 24-week treatment, with greater decrease in HD (P = 0.03) vs HF group (P = 0.08). Normalization in IGF-I values occurred in 27.6% of patients (P = 0.016 vs baseline), without a significant difference between HF and HD groups (P = 0.59). The decrease in serum IGF-I significantly correlated with serum LAN values (P = 0.04), and normalization of IGF-I was predicted by baseline IGF-I values (P = 0.02). Serum GH values did not change significantly (P = 0.22). Overall, 19 patients (63.3%) experienced adverse events, all being mild to moderate and transient, without differences between the two therapeutic arms. Conclusion: HF and HD LAN-ATG regimens are effective in normalizing IGF-I values in about one-third of patients with active acromegaly inadequately controlled by long-term conventional SRLs therapy.

Effects of high-dose octreotide LAR on glucose metabolism in patients with acromegaly inadequately controlled by conventional somatostatin analog therapy.

OBJECTIVE: In this study, the effect of high-dose octreotide LAR on glucose metabolism in patients with acromegaly was investigated. DESIGN: A post-hoc analysis of a clinical trial enrolling 26 patients with acromegaly not controlled by standard maximal somatostatin analog (SSAs) dose and randomized to receive high-dose (60  mg/28 days) or high-frequency (30  mg/21 days) octreotide i.m. injection (octreotide LAR) for 6 months. METHODS: Glucose metabolic status was defined as worsened when a progression from normoglycemia to impaired fasting glucose (IFG) or from IFG to diabetes occurred or when an increase of HbAlc by at least 0.5% was demonstrated. An improvement of glucose metabolism was defined in the presence of a regression from IFG to normoglycemia and/or when HbAlc decreased by at least 0.5%. RESULTS: Glucose metabolic status remained unchanged in a majority of patients (16/26 patients, 65.3%), worsened in six patients, and improved in four patients. Pre-existing metabolic status did not predict worsening of glucose metabolism, which, conversely, was significantly related to persistent biochemical activity of the disease. In fact, patients with worsened glucose metabolism exhibited a less frequent decrease in serum GH and IGF1 levels, compared with patients with improved or unchanged glucose metabolism (2/6 vs 18/20; P=0.01). CONCLUSION: An increase in octreotide LAR dose or frequency did not impact on glucose metabolism in most patients. Worsening of glucose metabolic status occurred in close relation with persistently uncontrolled acromegaly.

High-dose intramuscular octreotide in patients with acromegaly inadequately controlled on conventional somatostatin analogue therapy: a randomised controlled trial.

OBJECTIVE: In acromegaly, 25-50% of patients respond inadequately to conventional long-acting somatostatin analogue (SSA) therapy. Response may be improved by increasing SSA frequency or dose. This study evaluated the biochemical efficacy and safety of high-dose octreotide in patients with acromegaly. DESIGN: A 24-week prospective, multicentre, randomised, open-label trial conducted from 12 December 2005 to 23 October 2007 in patients with persistently uncontrolled acromegaly despite > or =6 month conventional SSA therapy. METHODS: Patients with > or =50% reduction in GH levels during previous SSA treatment were randomised to high-dose (60 mg/28 days) or high-frequency (30 mg/21 days) octreotide i.m. injection. Primary end-points were week 12 and 24 reduction in serum IGF1 and GH from baseline. Secondary end points included IGF1 normalisation and tumour shrinkage rates, and safety/tolerability evaluations. RESULTS: Significantly, more patients (10 out of 11) achieved week 24 IGF1 reduction in the high-dose than the high-frequency group (8 out of 15; P<0.05). In the high-dose group only, week-24 IGF1 values were significantly reduced (P=0.02) versus baseline. Normalisation of IGF1 occurred only with the high-dose regimen (4/11; P=0.02). Out of 14 patients experiencing adverse events, 5 reported drug-related gastrointestinal effects. No dose-response relationship was seen. Safety parameters were similar between treatment groups, apart from a slight decrease in HbA1c in the high-dose group only. CONCLUSION: High-dose octreotide treatment is safe and effective (normalisation of IGF1 levels) in a subset of patients with active acromegaly inadequately controlled with long-term SSA. Individualised octreotide doses up to 60 mg/28 days may improve outcomes of SSA therapy.

Identification of patients at low risk for thyroidectomy-related hypocalcemia by intraoperative quick PTH.

BACKGROUND: Transient hypoparathyroidism is a frequent and challenging complication following total thyroidectomy. The aim of the study was to identify patients at risk of developing thyroidectomy-related hypocalcemia and symptoms by means of the intraoperative quick parathyroid hormone (PTH) assay. METHODS: Eighty-one patients undergoing total thyroidectomy were included in the study. Quick PTH levels were measured at induction of anaesthesia and 10 minutes after total thyroidectomy. A sample of 10 patients who underwent unilateral thyroid lobectomy was considered as a control group. The accuracy of intraoperative PTH decline in predicting postoperative hypoparathyroidism was analysed. RESULTS: After total thyroidectomy, 27 patients (33.3%) developed postoperative hypocalcemia. Symptoms were reported by 21 patients (25.9%). The mean percentage decline of intraoperative quick PTH was 81% in hypocalcemic compared with 39% in normocalcemic patients (P<0.001), and it was 83% in symptomatic compared with 42% in asymptomatic patients (P<0.001). Mean proportion decline of quick PTH after unilateral lobectomy was 20%, significantly lower than the 53% registered after total thyroidectomy (P=0.005). Analysis of variation of intraoperative quick PTH with the receiver operator characteristics (ROC) curve showed a 75.7% decline as the cut-off value predicting postoperative hypocalcemia with the highest accuracy (91.4%) (sensitivity: 81.5% specificity: 96.3% positive likelihood ratio: 22; negative likelihood ratio: 0.2). Regarding the prediction of postoperative symptoms, a 79.5% decline was the most accurate (92.6%) cut-off point (sensitivity: 76.2% specificity: 98.3% positive likelihood ratio: 46; negative likelihood ratio: 0.2). CONCLUSIONS: Quick PTH monitoring during total thyroidectomy is a useful means for identifying low-risk patients for postoperative hypoparathyroidism and candidates for early, safe discharge. Furthermore, it is an objective method complementary to the surgeon's judgement of the intraoperative function of parathyroid glands, which should be implanted in the event of a 75%-80% decline.

Active acromegaly enhances spontaneous parathyroid hormone pulsatility.

In healthy subjects, parathyroid hormone (PTH) is secreted in a dual fashion, with low-amplitude and high-frequency pulses superimposed on tonic secretion. These 2 components of PTH secretion seem to have different effects on target organs. The aim of our study was to evaluate whether growth hormone excess in acromegaly may modify the spontaneous pulsatility of PTH. Five male patients with newly diagnosed active acromegaly and 8 healthy subjects were evaluated by 3-minute blood sampling for 6 hours. Plasma PTH concentrations were evaluated by multiparameter deconvolution analysis. Plasma PTH release profiles were also subjected to an approximate entropy (ApEn) estimate, which provides an ensemble measure of the serial regularity or orderliness of the release process. In acromegalic patients, baseline serum PTH values were not significantly different from those measured in the healthy subjects, as well as tonic PTH secretion rate, number of bursts, fractional pulsatile PTH secretion, and ApEn ratio. Conversely, PTH pulse half-duration was significantly longer in acromegalic patients vs healthy subjects (11.8+/-0.95 vs 6.9+/-1.6 minutes; P=.05), whereas PTH pulse mass showed a tendency (P=.06) to be significantly greater in acromegalic patients. These preliminary data suggest that growth hormone excess may affect PTH secretory dynamics in patients with acromegaly. Potentially negative bone effects of the modifications of PTH secretory pattern in acromegaly should be investigated.

Chronic glucocorticoid treatment alters spontaneous pulsatile parathyroid hormone secretory dynamics in human subjects.

OBJECTIVE: Spontaneous parathyroid hormone (PTH) secretory dynamics include tonic and pulsatile components. It is not known how glucocorticoids might alter these secretory dynamics. DESIGN: The aim of our study was to evaluate spontaneous fluctuations in serum PTH levels in six adult male patients (aged 31-64 years) receiving chronic (>6 months) therapy with glucocorticoids (daily dosage >7.5 mg of prednisone or dose equivalent of other corticosteroid) as compared with a control group of 10 age- and sex-matched normal subjects. METHODS: Peripheral venous blood sampling was performed every 3 min for 6 h from 0900 to 1500 h. Plasma PTH release profiles were subjected to deconvolution analysis, a method that resolves measured hormone concentrations into secretion and clearance components, and to an approximate entropy (ApEn) estimate, that in turn provides an integrated measure of the serial regularity or orderliness of the release process. RESULTS: In the glucocorticoid-treated group, the PTH tonic secretory rate was reduced (4.3+/-0.74 vs 8.8+/-1.4 pg/ml per min in controls, P = 0.017). There was, however, an increase in the fractional pulsatile PTH secretion (42+/-8.2 vs 18.3+/-3.9 pg/ml per min, P = 0.006) in glucocorticoid-treated vs normal subjects. Mean overall PTH concentration, as well as mean integrated area, was similar among normal and glucocorticoid-treated subjects. CONCLUSIONS: These results demonstrate, for the first time, that chronic glucocorticoid treatment induces a redistribution of spontaneous PTH secretory dynamics by reducing the amount released in tonic fashion and increasing the amount released as pulses.

Evaluation of soluble Fas ligand as a serological marker for melanoma.

BACKGROUND: Fas ligand (Fas-L), which is expressed by melanoma cells, can be cleaved from cell membranes and become soluble (soluble Fas-L, sFas-L). No previous study examined sFas-L levels in patients affected with all clinical stages of melanoma. OBJECTIVE: To investigate if sFas-L can be considered a serological marker for melanoma. METHODS: Serological sFas-L values in 114 patients with melanoma and 25 controls were measured by using ELISA. RESULTS: sFas-L values in patients were not significantly higher than in controls. They were not significantly different, moreover, when patient groups belonging to different clinical stages were compared with the control group. Two patients affected with distant metastases had the highest sFas-L values. CONCLUSION: sFas-L cannot be considered, within the limits of this study, as a serological marker for the detection of melanoma. Further studies are needed to evaluate whether sFas-L can be used as a marker for disease progression and/or prediction of therapy outcome.