Prognostic implication of sodium nitroprusside vasodilator test in pulmonary hypertension and left heart disease: insights from PUSHON registry

Background

Definition of combined post and pre-capillary pulmonary hypertension (Cpc-PH) is controversial, despite involving up to 25% of patients with heart failure with reduced ejection fraction (HFrEF). The 2019 World Symposium on PH focused on conflicting results and potential misleading interpretation of mean transpulmonary gradient (TPG) and diastolic transpulmonary gradient (DPG) in predicting outcomes in type 2 PH patients. A new Cpc-PH definition has been proposed, basing on pulmonary arterial wedge pressure (PAWP) >15 mmHg and pulmonary vascular resistance (PVR) >3 WU. In this setting, the role of vasodilator challenge has marginally been explored.

Purpose

This study aims to investigate whether vasodilator test increases prognostic accuracy in PH-LHD comparing to PVR and TPG.

Methods

125 patients with a first diagnosis of PH-LHD were selected within the PUlmonary hypertenSion in rigHt heart catheterization (PUSHON) registry. All patients underwent right heart catheterization and sodium nitroprusside vasodilator infusion. Hemodynamic response was defined as decrease of mean pulmonary arterial pressure (mPAP) <25 mmHg with maintenance of systemic systolic arterial pressure >85 mmHg. Primary endpoint was a composite of cardiac death, heart transplantation and urgent LVAD implant at 2 years.

Results

34 (27%) patients were sodium nitroprusside responders. Normalization of mPAP during acute vasodilator challenge was associated with higher event-free survival at 2 years (HR 2.46, 95% C.I. 1.29–4.69, p=0.006). Responders to nitroprusside showed lower baseline pressure regimens in pulmonary artery (sPAP 56.4±12.9 vs 63.2±12.4 mmHg, p=0.009; mPAP 38.1±6.9 vs 44.7±8.8 mmHg, p=0.001) and lower Wedge Pressure (25.1±6.6 vs 29.8±6.6 mmHg, p=0.001). Also, patients with positive vasodilator test showed better right ventricular function expressed by TAPSE (17.2±4.3 vs 15.4±3.8 mm, p=0.05) and higher EF (34.6±15.3% vs 28.1±13.1%, p=0.023). Interestingly, nitroprusside responders exhibited lower DPG (−0.11±5.30 vs 2.04±5.21 p=0.04). At multivariate analysis PVR and TPG ≥12 mmHg fail to independently predict primary endpoint, while positive vasodilator response was independently associated with better outcome (OR 0.22, 95% C.I. 0.09–0.52, p=0.001). The same results were confirmed in the Cpc-PH subgroup (OR 0.54, 95% C.I. 0.08–0.78, p=0.018).

Conclusions

Nitroprusside vasodilator response was associated with a higher event-free survival at 2 years follow-up in our cohort of patients with PH-LHD. Larger studies with prospective hemodynamic evaluations are needed to support our hypothesis.

Figure 1

Funding Acknowledgement

Type of funding source: None

COVID-19 therapies and their impact on QT interval prolongation: A multicentre retrospective study on 196 patients

Background

SARS-CoV-2 infection has caused a global pandemic. Many of the medications identified to treat COVID-19 could be connected with QTc prolongation and its consequences.

Methods

Non-ICU hospitalized patients of the three centres involved in the study from the 19th of March to the 1st of May were included in this retrospective multicentre study. Relevant clinical data were digitally collected. The primary outcome was the incidence of QTc prolongation ≥ 500 ms, the main secondary outcomes were the Tisdale score ability to predict QTc prolongation and the incidence of ventricular arrhythmias and sudden deaths.

Results

196 patients were analysed. 20 patients (10.2%) reached a QTc ≥ 500 ms. Patients with QTc ≥ 500 ms were significantly older (66.7 ± 14.65 vs 76.6 ± 8.77 years p: 0.004), with higher Tisdale score (low 56 (31.8%) vs 0; intermediate 95 (54.0%) vs 14 (70.0%); high 25 (14.2%) vs 6 (30.0%); p: 0.007) and with higher prognostic lab values (d-dimer 1819 ± 2815 vs 11486 ± 38554 ng/ml p: 0.010; BNP 212.5 ± 288.4 vs 951.3 ± 816.7 pg/ml p < 0.001; procalcitonin 0.27 ± 0.74 vs 1.33 ± 4.04 ng/ml p: 0.003). After a multivariate analysis the Tisdale score was able to predict a QTc prolongation ≥ 500 ms (OR 1,358 95% CI 1,076–1,714p: 0,010). 27 patients died because of COVID-19 (13.7%), none experienced ventricular arrhythmias, and 2 (1.02%) patients with concomitant cardiovascular condition died of sudden death.

Conclusions

In our population, a QTc prolongation ≥ 500 ms was observed in a minority of patients, no suspected fatal arrhythmias have been observed. Tisdale score can help in predicting QTc prolongation.

Patterns of brain structural changes in first-contact, antipsychotic drug-naive patients with schizophrenia

BACKGROUND AND PURPOSE

Previous studies have suggested that structural changes do occur in the brain of patients with schizophrenia compared with healthy control participants. However, findings from such studies are inconclusive, probably because of the different methodologic approaches, the clinical heterogeneity of patient samples, and also the fact that patients enrolled were treated with antipsychotic drugs. The aim of this study was to investigate brain GM volumes and intrinsic structural WM changes in first-contact, antipsychotic drug-naïve patients with schizophrenia.

MATERIALS AND METHODS

A total of 43 first-contact, drug-naïve, patients with schizophrenia and 17 age-matched control participants were studied. All participants underwent T1-weighted MR imaging and DTI scans. Voxel-based morphometry and tract-based spatial statistics were used to compare GM volumes and WM DTI metrics between groups. MR imaging measures were correlated with the duration of the untreated psychosis and the clinical positive and negative symptoms.

RESULTS

Compared with control participants, patients with schizophrenia showed smaller volumes of the temporal, parietal, and occipital GM, and a pattern of decreased mean diffusivity and increased fractional anisotropy in the brain stem and cerebellum bilaterally, interhemispheric and cortico-cortical connections bilaterally, and right anterior and posterior limb of the internal capsule. In patients, decreased mean diffusivity and increased fractional anisotropy in several brain regions were related to a longer duration of the untreated psychosis and the severity of positive symptoms.

CONCLUSIONS

First-contact, drug-naïve, patients with schizophrenia present with volumetric and DTI changes, which correlated with their clinical features. This study increases our knowledge on the neural networks involved in the pathophysiologic mechanisms of schizophrenia.

Clinical and metabolic effects of first-line treatment with somatostatin analogues or surgery in acromegaly: a retrospective and comparative study

To evaluate the metabolic effects of first-line somatostatin analogues or surgery in acromegaly. Retrospective, comparative, 12-month follow-up. Two hundred and thirty one patients (123 men, age 47.32 ± 14.63 years) with active acromegaly, first line treatments were somatostatin analogues in 151 (65.4%) and surgery in 80 (34.6%). Metabolic syndrome (MS) parameters, glucose, insulin and GH during oral glucose tolerance test, stimulated insulin sensitivity by insulin sensitivity index (ISI Matsuda), early and total insulin-secretion rate by insulinogenic index and AUC(INS), visceral adiposity function, expressed by visceral adipose index (VAI). Somatostatin analogues treatment improved all MS parameters and significantly reduced fasting glucose (P < 0.001), HbA1c (P = 0.014) and the prevalence of DM (P = 0.003) when disease control was achieved. Both somatostatin analogues and surgery improved ISI Matsuda (P < 0.001) and reduced AUC(INS) (P < 0.001) and VAI (P < 0.001 and P = 0.003, respectively). Only in controlled somatostatin analogues-treated patients a significant reduction in insulinogenic index (P = 0.010) was observed. ISI Matsuda showed a significant independent correlation with IGF-1 levels (β = -0.258; P = 0.001) and VAI score (β = -0.430; P < 0.001). VAI was independently correlated with IGF-1 (β = 0.183; P = 0.004). Both somatostatin analogues and surgery can safely be used as first-line therapy in acromegaly, without any untoward effects on glucose tolerance. The control of acromegaly is the main determinant of beneficial effects on general features of insulin sensitivity. VAI could represent an additional link between disease control and insulin sensitivity.

Janus kinase (JAK) 2 V617F mutation as the cause of primary thrombocythemia in acromegaly with severe visceromegaly and divergence between growth hormone and insulin-like growth factor-1 concentrations during the follow-up: causal or casual association?

OBJECTIVE

An increased prevalence of hematological abnormalities is reported in acromegaly, but to date no reports about the presence of the Janus Kinase (JAK) 2 mutation in acromegalic patients have been described.

DESIGN

We report the complex clinical presentation of the unique case, never described, of acromegaly due to GH-secreting pituitary adenoma associated with JAK2 V617F mutation.

RESULTS

The patient shows primary thrombocythemia and myelofibrosis, due to JAK2 V617F mutation, severe visceromegaly and a peculiar clinical course of the disease characterized by discrepant values of GH and IGF-1 during somatostatin analog (SA) treatment despite a significant reduction in pituitary adenoma size and therapeutic resistance both to SA and pegvisomant.

CONCLUSIONS

The presence of JAK2 V617F mutation is a cause of primary thrombocythemia and myelofibrosis in acromegaly. In this patient, a peculiar clinical course of acromegaly was observed, with the difficulty in controlling the disease. More data, on a larger cohort of patients, could clarify whether JAK2 V617F mutation has a serious impact on the clinical features and course of acromegaly.

In vitro phenotypic, genomic and proteomic characterization of a cytokine-resistant murine β-TC3 cell line

Type 1 diabetes mellitus (T1DM) is caused by the selective destruction of insulin-producing β-cells. This process is mediated by cells of the immune system through release of nitric oxide, free radicals and pro-inflammatory cytokines, which induce a complex network of intracellular signalling cascades, eventually affecting the expression of genes involved in β-cell survival.

The aim of our study was to investigate possible mechanisms of resistance to cytokine-induced β-cell death. To this purpose, we created a cytokine-resistant β-cell line (β-TC3R) by chronically treating the β-TC3 murine insulinoma cell line with IL-1β + IFN-γ. β-TC3R cells exhibited higher proliferation rate and resistance to cytokine-mediated cell death in comparison to the parental line. Interestingly, they maintained expression of β-cell specific markers, such as PDX1, NKX6.1, GLUT2 and insulin. The analysis of the secretory function showed that β-TC3R cells have impaired glucose-induced c-peptide release, which however was only moderately reduced after incubation with KCl and tolbutamide. Gene expression analysis showed that β-TC3R cells were characterized by downregulation of IL-1β and IFN-γ receptors and upregulation of SOCS3, the classical negative regulator of cytokines signaling. Comparative proteomic analysis showed specific upregulation of 35 proteins, mainly involved in cell death, stress response and folding. Among them, SUMO4, a negative feedback regulator in NF-kB and JAK/STAT signaling pathways, resulted hyper-expressed. Silencing of SUMO4 was able to restore sensitivity to cytokine-induced cell death in β-TC3R cells, suggesting it may play a key role in acquired cytokine resistance by blocking JAK/STAT and NF-kB lethal signaling.

In conclusion, our study represents the first extensive proteomic characterization of a murine cytokine-resistant β-cell line, which might represent a useful tool for studying the mechanisms involved in resistance to cytokine-mediated β-cell death. This knowledge may be of potential benefit for patients with T1DM. In particular, SUMO4 could be used as a therapeutical target.

Visceral adiposity index is associated with significant fibrosis in patients with non-alcoholic fatty liver disease

BACKGROUND

Metabolic factors have been associated with liver damage in patients with non-alcoholic fatty liver disease (NAFLD).

AIMS

To test a new marker of adipose dysfunction, the visceral adiposity index (VAI), in NAFLD patients to assess whether or not it is associated with host factors, and to investigate a potential correlation with histological findings.

METHODS

One hundred and forty-two consecutive NAFLD patients were evaluated by liver biopsy, and clinical and metabolic measurements, including insulin resistance with the homeostasis model assessment (HOMA), and VAI by using waist circumference, body mass index, triglycerides and HDL. Serum levels of TNFα, IL-6, adiponectin and leptin were also assessed. All biopsies were scored for NAFLD activity score (NAS) and its components, and for staging (Kleiner).

RESULTS

By multiple linear regression analysis, VAI was independently associated with higher HOMA (P = 0.04), and fibrosis (P = 0.04). In addition, an independent association was found between higher VAI and lower adiponectin levels (P = 0.002). Higher HOMA (OR 1.149, 95% CI 1.003-1.316, P = 0.04), higher VAI (OR 1.446, 95% CI 1.023-2.043, P = 0.03), lobular inflammation (OR 3.777, 95% CI 1.771-8.051, P = 0.001), and ballooning (OR 2.884, 95% CI 1.231-6.757, P = 0.01) were correlated with significant fibrosis (F2-F4) on multiple logistic regression analysis. In particular, the prevalence of significant fibrosis progressively increased from patients with a VAI ≤ 2.1 and HOMA ≤ 3.4 (26%) to those with a VAI > 2.1 and HOMA > 3.4 (83%).

CONCLUSIONS

In NAFLD patients, visceral adiposity index is an expression of both qualitative and quantitative adipose tissue dysfunction and, together with insulin resistance, is independently correlated with significant fibrosis.

BRAFV600E mutation, TIMP-1 upregulation, and NF-κB activation: closing the loop on the papillary thyroid cancer trilogy

BRAF(V600E) is the most common mutation found in papillary thyroid carcinoma (PTC). Tissue inhibitor of metalloproteinases (TIMP-1) and nuclear factor (NF)-κB have been shown to play an important role in thyroid cancer. In particular, TIMP-1 binds its receptor CD63 on cell surface membrane and activates Akt signaling pathway, which is eventually responsible for its anti-apoptotic activity. The aim of our study was to evaluate whether interplay among these three factors exists and exerts a functional role in PTCs. To this purpose, 56 PTC specimens were analyzed for BRAF(V600E) mutation, TIMP-1 expression, and NF-κB activation. We found that BRAF(V600E) mutation occurs selectively in PTC nodules and is associated with hyperactivation of NF-κB and upregulation of both TIMP-1 and its receptor CD63. To assess the functional relationship among these factors, we first silenced BRAF gene in BCPAP cells, harboring BRAF(V600E) mutation. We found that silencing causes a marked decrease in TIMP-1 expression and NF-κB binding activity, as well as decreased invasiveness. After treatment with specific inhibitors of MAPK pathway, we found that only sorafenib was able to increase IκB-α and reduce both TIMP-1 expression and Akt phosphorylation in BCPAP cells, indicating that BRAF(V600E) activates NF-κB and this pathway is MEK-independent. Taken together, our findings demonstrate that BRAF(V600E) causes upregulation of TIMP-1 via NF-κB. TIMP-1 binds then its surface receptor CD63, leading eventually to Akt activation, which in turn confers antiapoptotic behavior and promotion of cell invasion. The recognition of this functional trilogy provides insight on how BRAF(V600E) determines cancer initiation, progression, and invasiveness in PTC, also identifying new therapeutic targets for the treatment of highly aggressive forms.

Cut-off points of the visceral adiposity index (VAI) identifying a visceral adipose dysfunction associated with cardiometabolic risk in a Caucasian Sicilian population

BACKGROUND

The Visceral Adiposity Index (VAI) is a sex-specific mathematical index, based on Waist Circumference (WC), Body Mass Index (BMI), triglycerides (TG) and HDL cholesterol (HDL) levels, indirectly expressing visceral adipose function and insulin sensitivity. Our aim was to find the optimal cut-off points of VAI identifying a visceral adipose dysfunction (VAD) associated with cardiometabolic risk in a Caucasian Sicilian population.

METHODS

Medical check-up data of 1,764 Primary Care patients (PC patients) were retrospectively and cross-sectionally examined using a receiver-operating characteristic (ROC) curve to determine appropriate stratified-for-age cut-off of VAI, for the identification of PC patients with Metabolic Syndrome (MetS) according to the NCEP-ATP III criteria. The PC patients with higher VAI scores were subdivided into three groups according to VAI tertiles (i.e. PC patients with mild VAD, moderate VAD or severe VAD). Finally, VAD classes were compared to classical cardio- and cerebrovascular risk factors as independent predictors of coronary heart disease and/or myocardial infarction, transient ischemic attack and/or ischemic stroke.

RESULTS

Moderate and severe VADs proved to be independently associated with cardiovascular events [(OR: 5.35; 95% CI: 1.92-14.87; p = 0.001) and (OR: 7.46; 95% CI: 2.64-21.05; p < 0.001) respectively]. Mild, moderate and severe VADs were found to be independently associated with cerebrovascular events [(OR: 2.73; 95% CI: 1.12-6.65; p = 0.027), (OR: 4.20; 95% CI: 1.86-9.45; p = 0.001) and (OR: 5.10; 95% CI: 2.14-12.17; p < 0.001) respectively].

CONCLUSIONS

Our study suggests that among Caucasian Sicilian subjects there are clear cut-off points of VAI able to identify a VAD strongly associated with cardiometabolic risk.

Low estradiol-to-testosterone ratio is associated with oligo-anovulatory cycles and atherogenic lipidic pattern in women with polycystic ovary syndrome

OBJECTIVE

The estradiol-to-testosterone (E2/T) ratio has been investigated in different diseases but few in vivo data are available with regard to its role in women with ovary syndrome (PCOS). The aim of this study was to evaluate the role of the E2/T ratio in the ovulatory function and metabolic pattern in such women.

METHODS

We retrospectively evaluated hyperandrogenemia, clinical hyperandrogenism, ovarian morphology, hypothalamo-hypophyseal axis and metabolic syndrome parameters in a cohort of 202 consecutive women affected by PCOS. An oral glucose tolerance test measured areas under the curve for insulin (AUC(2hIRI)), for glucose (AUC(2hglucose)), and the HOMA-IR and Matsuda index of insulin resistance were evaluated. Serum progesterone (Pg) was determined from day 20 to day 24 of the menstrual cycle and chronic oligo-anovulation was established if two consecutive cycles were anovulatory.

RESULTS

Women with PCOS with normal ovulation [66/202 (32.7%)] showed a significantly higher E2/T ratio than women with PCOS with chronic oligo/anovulation [136/202 (67.3%)] (p < 0.05). Using a series of multiple linear regression models, we also investigated which variables correlated with the E2/T ratio. The analysis showed a strongly positive correlation of the E2/T ratio with Pg (β =  0.473, p < 0.001) and a negative correlation with total cholesterol (β =  -0.433, p < 0.001).

CONCLUSIONS

Our data suggest that in women with PCOS a low E2/T ratio is not only associated with chronic oligo-anovulation, but is also a determinant factor of the atherogenic lipid profile.

In vitro generation of pancreatic endocrine cells from human adult fibroblast-like limbal stem cells

Stem cells might provide unlimited supply of transplantable cells for β-cell replacement therapy in diabetes. The human limbus is a highly specialized region hosting a well-recognized population of epithelial stem cells, which sustain the continuous renewal of the cornea, and the recently identified stromal fibroblast-like stem cells (f-LSCs), with apparent broader plasticity. However, the lack of specific molecular markers for the identification of the multipotent limbal subpopulation has so far limited the investigation of their differentiation potential. In this study we show that the human limbus contains uncommitted cells that could be potentially harnessed for the treatment of diabetes. Fourteen limbal biopsies were obtained from patients undergoing surgery for ocular diseases not involving the conjunctiva or corneal surface. We identified a subpopulation of f-LSCs characterized by robust proliferative capacity, expressing several pluripotent stem cell markers and exhibiting self-renewal ability. We then demonstrated the potential of f-LSCs to differentiate in vitro into functional insulin-secreting cells by developing a four-step differentiation protocol that efficiently directed f-LSCs towards the pancreatic endocrine cell fate. The expression of specific endodermal, pancreatic, islet, and β-cell markers, as well as functional properties of f-LSC-derived insulin-producing cells, were evaluated during differentiation. With our stage-specific approach, up to 77% of f-LSCs eventually differentiated into cells expressing insulin (also assessed as C-peptide) and exhibited phenotypic features of mature β-cells, such as expression of critical transcription factors and presence of secretory granules. Although insulin content was about 160-fold lower than what observed in adult islets, differentiated cells processed ∼98% of their proinsulin content, similar to mature β-cells. Moreover, they responded in vitro in a regulated manner to multiple secretory stimuli, including glucose. In conclusion, f-LSCs represent a possible relevant source of autologous, transplantable, insulin-producing cells that could be tested for the reversal of diabetes.

Predictors of microvascular complications in type 1 diabetic patients at onset: the role of metabolic memory

BACKGROUND

Several epidemiological studies showed a close association between metabolic control and microvascular complications in type 1 Diabetes Mellitus (T1DM). The aim of our longitudinal observational study was to evaluate the predictive role of the main clinical and biochemical parameters in determining microvascular complications.

METHODS

376 T1DM patients, hospitalized in our division from 1991 to 2005 (mean follow-up=10.93±4.26 years) were studied. Stepwise Cox regression analysis was used to identify the influence of residual ß-cell function, ß-cell autoimmunity, HbA1c levels and other clinical and laboratory parameters in the development of microalbuminuria and retinopathy.

RESULTS

The probability of developing microalbuminuria was higher in males than in females (HR 1.82; 95% CI 1.01-3.28; p=0.044), in patients with higher mean HbA1c values (HR 2.80; 95% CI 1.63-4.83; p<0.001), longer duration of disease (HR 1.98; 95% CI 1.10-3.57; p=0.022) and younger age of diabetes onset (HR 0.53; 95% CI 0.03-0.92; p=0.026). An increased probability of developing retinopathy was found in patients with higher mean HbA1c levels during follow-up (HR 2.35; 95% CI 1.34-4.12, p=0.003), as well as at onset (HR 1.85; 95% CI 1.06-3.24; p=0.030).

CONCLUSIONS

Our study suggests that among the clinical, metabolic, immunological and biochemical factors evaluated at onset, only HbA1c is predictive for the microangiopathy development in T1DM.

Cornea in acromegalic patients as a possible target of growth hormone action

BACKGROUND

GH exerts its effects on many organs and the eye also seems to be a target site, although few authors have investigated the corneal thickness in patients with acromegaly.

AIM

To perform a detailed ophthalmological evaluation in acromegalic patients, in relation to disease activity.

MATERIAL AND METHODS

Twenty-eight acromegalic patients (11 males, 17 females) and 22 voluntary healthy subjects underwent complete metabolic and ophthalmological evaluation, including retinal thickness (RT), central corneal thickness (CCT), and intraocular pressure values (IOP).

RESULTS

Significantly greater CCT values were found in all acromegalic patients in comparison with controls (567 vs 528.5 μm; p<0.001), without concomitant greater corrected IOP. No difference was found for RT. Analyzing these data according to disease activity, uncontrolled patients showed greater CCT values (573.5 vs 559 μm; p=0.002) and corrected IOP (17.4 vs 16 mmHg; p=0.001) than the controlled ones. CCT also correlated with basal and nadir GH after oral glucose load levels, IGF-I levels, and duration of active disease.

CONCLUSIONS

Acromegaly is characterized by greater CCT values, supporting the hypothesis that GH excess may have stimulatory effects on the cornea as well as on other target organs. Higher GH levels, disease control status and duration of active disease seem to be the main causes of increased corneal thickness. We suggest a careful and detailed corneal evaluation in acromegalic patients to prevent the potential risk of increased IOP, in addition to the already-known complications.

Visceral adiposity index is associated with histological findings and high viral load in patients with chronic hepatitis C due to genotype 1

Metabolic factors have been associated with liver damage in patients with genotype 1 chronic hepatitis C (G1 CHC). We tested visceral adiposity index (VAI), a new marker of adipose dysfunction in G1 CHC, patients to assess its association with host and viral factors and its link to both histological findings and sustained virological response (SVR). Two hundred thirty-six consecutive G1 CHC patients were evaluated by way of liver biopsy and anthropometric and metabolic measurements, including insulin resistance (IR), homeostasis model assessment (HOMA), and VAI using waist circumference, body mass index, triglycerides, and high-density lipoprotein cholesterol. All biopsies were scored by one pathologist for staging and grading and graded for steatosis, which was considered moderate to severe if ≥ 30%. Multiple linear regression analysis revealed that VAI score was independently associated with higher HOMA score (P = 0.009), log10 hepatitis C virus RNA levels (P = 0.01), necroinflammatory activity (P = 0.04), and steatosis (P = 0.04). Multiple logistic regression analysis revealed that IR (OR 3.879, 95% CI 1.727-8.713, P = 0.001), higher VAI score (OR 1.472, 95% CI 1.051-2.062, P = 0.02), and fibrosis (OR 2.255, 95% CI 1.349-3.768, P = 0.002) were linked to steatosis ≥ 30%. Logistic regression analysis revealed that older age (OR 1.030, 95% CI 1.002-1.059, P = 0.03), higher VAI score (OR 1.618, 95% CI 1.001-2.617, P = 0.04), and fibrosis (OR 2.608, 95% CI 1.565-4.345, P < 0.001) were independently associated with moderate to severe necroinflammatory activity. No independent associations were found between VAI score and both fibrosis and SVR.

CONCLUSION

In G1 CHC patients, higher VAI score is independently associated with both steatosis and necroinflammatory activity and has a direct correlation with viral load.

OCT is not useful for detection of minimal diabetic retinopathy in type 1 diabetes

Optical coherence tomography (OCT) has been proven useful in measuring retinal thickness (RT) in patients with diabetes, although with discordant results in different studies. We examined RT in patients with type 1 diabetes (T1D) with or without minimal diabetic retinopathy (MDR) to test whether OCT is able to identify early retinal changes and potential correlations with metabolic parameters. RT of 102 patients with T1D (53 females, 49 males, aged 27.03 +/- 7.4 years) and of 42 healthy controls was examined, with analysis of nine different sectors (fovea, four pericentral and four peripheral sectors). According to the results of basal fundus photography, patients were divided into two groups, without MDR (48 cases) and with MDR (54 cases). Patients with proliferative DR or macular edema were excluded. No difference was found between patients with or without MDR and the control group for all OCT parameters investigated. Mean HbA1c of the last 5 years (P < 0.001), microalbuminuria (P = 0.002), total (P = 0.046) and LDL cholesterol (P = 0.007) and triglyceride (P < 0.001) levels were higher in patients with MDR, along with higher prevalence of hypertension (P = 0.013), younger age at diagnosis (P = 0.018) and longer diabetes duration (P < 0.001) with regard to the patients without MDR and controls, although no significant correlation between these parameters and RT was found. Our study suggests that MDR without macular edema in patients with T1D cannot be detected with OCT. Therefore, the conventional diagnostic methods are mandatory to detect early DR.

Visceral Adiposity Index: a reliable indicator of visceral fat function associated with cardiometabolic risk

OBJECTIVE

To individuate a novel sex-specific index, based on waist circumference, BMI, triglycerides, and HDL cholesterol, indirectly expressing visceral fat function.

RESEARCH DESIGN AND METHODS

Visceral adiposity index (VAI) was first modeled on 315 nonobese healthy subjects. Using two multiple logistic regression models, VAI was retrospectively validated in 1,498 primary care patients in comparison to classical cardio- and cerebrovascular risk factors.

RESULTS

All components of metabolic syndrome increased significantly across VAI quintiles. VAI was independently associated with both cardiovascular (odd ratio [OR] 2.45; 95% CI 1.52-3.95; P < 0.001) and cerebrovascular (1.63; 1.06-2.50; P = 0.025) events. VAI also showed significant inverse correlation with insulin sensitivity during euglycemic-hyperinsulinemic clamp in a subgroup of patients (R(s) = -0.721; P < 0.001). By contrast, no correlations were found for waist circumference and BMI.

CONCLUSIONS

Our study suggests VAI is a valuable indicator of "visceral adipose function" and insulin sensitivity, and its increase is strongly associated with cardiometabolic risk.

Adrenal morphology and function in acromegalic patients in relation to disease activity

Visceromegaly is a common consequence of acromegaly. However, few studies investigated the chronic effects of growth hormone on adrenal glands. Our aim was to evaluate adrenal morphology and function in a cohort of acromegalic patients in relation to disease activity. Twenty-six acromegalics (10 males and 16 females) and 21 healthy subjects were investigated. Gland morphology was evaluated by computerized axial tomography, measuring central, lateral, and medial adrenal segments. Uncontrolled acromegalics showed increased volume of all adrenal segments, higher urinary free cortisol (UFC), and lower morning adrenocorticotropic hormone in comparison with healthy subjects. However, normal cortisol levels after low-dose dexamethasone suppression test indicated a preserved regulation of the hypothalamic-pituitary-adrenal axis. In addition, uncontrolled patients showed greater medial segment of right gland, higher UFC, and aldosterone levels with respect to controlled patients. All acromegalics did not show any difference in adrenal size when grouped according to UFC/24 h levels. In addition, no difference was found in any of the parameters between normotensive and hypertensive patients. In conclusion, our findings confirm that acromegaly affects adrenal size as well as other organs. In addition, we report a stimulatory effect of growth hormone on adrenal function, although the regulation of the hypothalamic-pituitary-adrenal axis is preserved.

In vitro identification and characterization of CD133(pos) cancer stem-like cells in anaplastic thyroid carcinoma cell lines

Background

Recent publications suggest that neoplastic initiation and growth are dependent on a small subset of cells, termed cancer stem cells (CSCs). Anaplastic Thyroid Carcinoma (ATC) is a very aggressive solid tumor with poor prognosis, characterized by high dedifferentiation. The existence of CSCs might account for the heterogeneity of ATC lesions. CD133 has been identified as a stem cell marker for normal and cancerous tissues, although its biological function remains unknown.

Methodology/Principal Findings

ATC cell lines ARO, KAT-4, KAT-18 and FRO were analyzed for CD133 expression. Flow cytometry showed CD133^pos cells only in ARO and KAT-4 (64±9% and 57±12%, respectively). These data were confirmed by qRT-PCR and immunocytochemistry. ARO and KAT-4 were also positive for fetal marker oncofetal fibronectin and negative for thyrocyte-specific differentiating markers thyroglobulin, thyroperoxidase and sodium/iodide symporter. Sorted ARO/CD133^pos cells exhibited higher proliferation, self-renewal, colony-forming ability in comparison with ARO/CD133^neg. Furthermore, ARO/CD133^pos showed levels of thyroid transcription factor TTF-1 similar to the fetal thyroid cell line TAD-2, while the expression in ARO/CD133^neg was negligible. The expression of the stem cell marker OCT-4 detected by RT-PCR and flow cytometry was markedly higher in ARO/CD133^pos in comparison to ARO/CD133^neg cells. The stem cell markers c-KIT and THY-1 were negative. Sensitivity to chemotherapy agents was investigated, showing remarkable resistance to chemotherapy-induced apoptosis in ARO/CD133^pos when compared with ARO/CD133^neg cells.

Conclusions/Significance

We describe CD133^pos cells in ATC cell lines. ARO/CD133^pos cells exhibit stem cell-like features - such as high proliferation, self-renewal ability, expression of OCT-4 - and are characterized by higher resistance to chemotherapy. The simultaneous positivity for thyroid specific factor TTF-1 and onfFN suggest they might represent putative thyroid cancer stem-like cells. Our in vitro findings might provide new insights for novel therapeutic approaches.

Insulin resistance and polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is one of the most common endocrine disorders in humans, affecting approximately 7-8% of women of reproductive age. Despite the criteria adopted, PCOS is considered to be a predominantly hyperandrogenetic syndrome and the evaluation of metabolic parameters and insulin sensitivity is not mandatory. Most women with PCOS also exhibit features of the metabolic syndrome, including insulin resistance, obesity and dyslipidaemia. While the association with type 2 diabetes is well established, whether the incidence of cardiovascular disease is increased in women with PCOS remains unclear. Acknowledging the strong impact of insulin-resistance in the genesis of PCOS could be helpful not only to make the diagnosis more robust, but also for conferring better cardiovascular risk prevention. Several current studies support a strong recommendation that women with PCOS should undergo comprehensive evaluation for the metabolic syndrome and recognized cardiovascular risk factors, and receive appropriate treatment as needed. Lifestyle modifications remain the first-line therapy for all obese women with PCOS. However, many of these women do not lose weight easily. Insulin-sensitizing drugs are discussed as a promising and unique therapeutic option for the chronic treatment of PCOS.

The evaluation of metabolic parameters and insulin sensitivity for a more robust diagnosis of the polycystic ovary syndrome

BACKGROUND

Polycystic ovary syndrome (PCOS) is considered predominantly as a hyperandrogenetic syndrome and the evaluation of metabolic parameters and insulin sensitivity is not mandatory.

CONTEXT

PCOS diagnostic criteria [National Institute of Health (NIH), Rotterdam Consensus (ROT), Androgen Excess Society (AES)] are unanimous recognized. We aimed to assess in women with suspected PCOS whether the application of the three diagnostic criteria differently characterizes the metabolic profile and insulin sensitivity.

DESIGN

Retrospective study in a cohort of women admitted to our Outpatient Clinic for suspected PCOS.

PATIENTS

Two hundred and four women with suspected PCOS in comparison to a group of normal, age-matched Sicilian women (N = 34) without signs of metabolic syndrome.

MEASUREMENTS

We evaluated hyperandrogenaemia and clinical hyperandrogenism, ovarian morphology, hypothalamo-hypophyseal axis and metabolic syndrome parameters. An oral glucose tolerance test (OGTT; 75 g glucose) measured areas under the curve (AUC) for insulin, C peptide and homeostasis model assessment of insulin-resistance (HOMA-IR) were performed.

RESULTS

The prevalence of PCOS was 51% according to NIH, 83% to ROT and 70.6% to AES, and only 100 patients were qualified simultaneously under these three criteria. The prevalence of the metabolic syndrome in PCOS women was 26.92% (NIH), 21.77% (ROT) and 23.61% (AES), respectively. In comparison to healthy women, PCOS women showed increased fasting insulinaemia (PCOS/ROT: P = 0.028; PCOS/NIH: P = 0.007; PCOS/EAS: P = 0.023), 120 min insulin after OGTT insulinaemia (for the three criteria: P < 0.001), AUC(2h) insulin (for the three criteria: P < 0.001) and AUC(2h) C peptide (for the three criteria: P < 0.001).

CONCLUSIONS

Our study highlights the fact that regardless of the diagnostic criteria used, evaluation of the metabolic parameters and insulin sensitivity is important for a correct diagnosis of PCOS and a therapeutic approach.

Identification of tyrosine phosphatase 2(256-760) construct as a new, sensitive marker for the detection of islet autoimmunity in type 2 diabetic patients: the non-insulin requiring autoimmune diabetes (NIRAD) study 2

OBJECTIVE

The presence of autoantibodies to islet antigens GAD and/or tyrosine phosphatase 2 (IA-2) in type 2 diabetic patients (latent autoimmune diabetes in adults [LADA]) identifies subjects at high risk to develop insulin dependency. The aim of this study was to dissect humoral anti-IA-2 immune response in Caucasian LADA patients, identifying the most sensitive construct to evaluate IA-2 immunoreactivity and comparing LADA IA-2 epitope specificities to those found in type 1 diabetes.

RESEARCH DESIGN AND METHODS

We analyzed 177 LADA and 978 type 2 diabetic patients with different disease duration, collected in a nationwide Italian survey, the Non-Insulin Requiring Autoimmune Diabetes (NIRAD) study aimed at assessing prevalence and characteristics of autoimmune diabetes in type 2 diabetic patients and 106 newly diagnosed type 1 diabetic patients (53 children, 53 adults). By radioimmunoassay, we analyzed humoral immunoreactivity to seven IA-2 constructs: IA-2(PTP (687-979)), IA-2((761-964)), IA-2((256-760)), IA-2(JM (601-630)), IA-2(IC (605-979)), IA-2(BDC (256-556:630-979)), and IA-2(FL (1-979)).

RESULTS

IA-2((256-760)) fragment was identified as the marker with the highest sensitivity for detection of humoral IA-2 immunoreactivity in LADA patients, identifying IA-2 autoantibodies in approximately 30% of GAD antibody (GADA)-positive LADA patients and in 3.4% of GADA-negative type 2 diabetic patients. LADA IA-2((256-760))A positivity was associated with an increased frequency of autoimmune diabetes HLA-susceptible genotypes and with a higher risk for developing thyroid autoimmunity compared with autoantibody-negative type 2 diabetic patients. At disease diagnosis, adult-onset type 1 diabetic and LADA patients showed a lower IA-2 COOH-terminal immunoreactivity compared with childhood-onset type 1 diabetic patients.

CONCLUSIONS

IA-2 immunoreactivity in LADA patients has thus far been underestimated, and IA-2((256-760)) autoantibody detection may represent a novel diagnostic tool for the identification of islet autoimmunity in these patients.

Outcome of pregnancy in type 1 diabetic patients treated with insulin lispro or regular insulin: an Italian experience

Some studies have shown that fetal outcome observed in patients using insulin lispro is much the same as in pregnant women using regular insulin. This study aims to analyze the Italian data emerging from a multinational, multicenter, retrospective study on mothers with type 1 diabetes mellitus before pregnancy, comparing those treated with insulin lispro for at least 3 months before and 3 months after conception with those treated with regular insulin. The data collected on pregnant women with diabetes attending 15 Italian centers from 1998 to 2001 included: HbA1c at conception and during the first and third trimesters, frequency of severe hypoglycemic episodes, spontaneous abortions, mode and time of delivery, fetal malformations and mortality. Seventy-two diabetic pregnancies treated with lispro and 298 treated with regular insulin were analyzed, revealing a trend towards fewer hypoglycemic episodes in the former, who also had a significantly greater reduction in HbA1c during the first trimester. The rate of congenital malformations was similar in the offspring of the two groups of women treated with insulin lispro or regular insulin. These findings suggest that insulin lispro could be useful for the treatment of hyperglycemia in type 1 diabetic pregnant women.

Markers of inflammation and prevalence of vascular disease in patients with metabolic syndrome

AIM

The aim of this study was to determine the prevalence of carotid atherosclerosis and coronary heart disease and cerebrovascular disease in subjects with metabolic syndrome and to investigate the relationship between atherosclerosis and C-reactive protein (CRP) levels.

METHODS

We studied 568 ambulatory subjects, referred to our Center for the study of atherosclerosis and cardiovascular prevention by general practitioner, for the presence of traditional cardiovascular risk factors. Subjects were divided in two groups: those with metabolic syndrome (n=163), and those with 0-2 metabolic abnormalities (n=405). All subjects underwent carotid artery ultrasound and blood tests including high sensitivity-CRP measurement.

RESULTS

Prevalence of carotid lesions, previous cardiac or cerebrovascular events was higher in patients with metabolic syndrome. CRP levels were higher in patients with metabolic syndrome (0.6+/-0.23 vs 0.42+/-0.2, P<0.01). An increased relative risk for carotid atherosclerosis, coronary heart disease and cerebrovascular disease was not associated with each single component of the metabolic syndrome, but it was significantly associated with the coexistence of three or more of these. Patients with the metabolic syndrome had a higher incidence of carotid and coronary disease, if CRP levels were above 0.3 mg/dL.

CONCLUSION

Patients with metabolic syndrome are at increased risk for cardiovascular events. Strategy to treat these patients is not well clarified. Life style changes are mandatory, but in very high-risk subgroups secondary prevention strategies may be advisable. These may be identified by using CRP levels as a marker.

Fine-needle aspiration molecular analysis for the diagnosis of papillary thyroid carcinoma through BRAF V600E mutation and RET/PTC rearrangement

OBJECTIVE

To evaluate BRAF(V600E) mutation on consecutive fine-needle aspiration biopsy (FNAB) specimens in order to assess FNAB's usefulness in preoperative papillary thyroid carcinoma (PTC) diagnosis with the contemporaneous analysis of RET/PTC1 and RET/PTC3 rearrangements obtained from ex vivo thyroid nodules.

DESIGN

Thyroid FNABs from 156 subjects with nodules and 49 corresponding surgical samples were examined for the presence of BRAF mutation by real-time allele-specific polymerase chain reaction, confirmed with the use of a laser pressure catapulting system. Samples were also examined for RET/PTC rearrangements. The results were compared with the cytological diagnosis and histopathology.

MAIN OUTCOMES

13/156 cytological examinations were diagnostic for PTC and 19/156 showed suspicious/indeterminate FNAB (12.2%). FNAB-BRAF(V600E) mutation was detected in 11/16 (69%) cases with histological confirmation of PTC. In our series, RET/PTC rearrangement was detected in only one case of PTC, whereas it was not present in any case of adenoma, goiter, or Hashimoto's thyroiditis. No PTC case was found positive at the same time for BRAF mutation and RET/PTC rearrangements.

CONCLUSION

BRAF(V600E) mutation detected on FNAB specimens, more than RET/PTC rearrangements, is highly specific for PTC and its routine research might well be an adjunctive and integrative diagnostic tool for the preoperative diagnostic iter.

Metabolic parameters and adipokine profile during GH replacement therapy in children with GH deficiency

OBJECTIVE

GH replacement therapy in children with GH deficiency (GHD) mainly promotes linear growth. Not only have very few studies fully analyzed the metabolic consequences of GH therapy, but also the question as to whether GH may affect adipokine secretion has been insufficiently investigated. Our aim was to study the effects of GH replacement therapy on auxological data, lipid and glycemic profiles, insulin homeostasis (HOMA-IR) and serum adipokines in children.

METHODS

This was a 1-year prospective study. Thirty-four GHD children (11.6 +/- 2.6 years) and thirty healthy matched controls were enrolled. Children affected by GHD were studied both before beginning continuous GH replacement therapy and again at 12 months.

RESULTS

At the beginning of the study, total and LDL cholesterol were higher in GHD children than in controls (P<0.001), whereas HDL cholesterol, triglycerides, insulin, HOMA-IR, leptin, and adiponectin were similar. At 12 months of continuous GH replacement therapy in the GHD group, there was a significant increase in both auxological data and IGF-I (P<0.001); total cholesterol (P<0.001), LDL (P<0.001), triglycerides (P<0.005), and leptin (P<0.001) decreased significantly; HDL (P<0.003), insulin (P<0.001), HOMA-IR (P<0.001) increased while adiponectin was unmodified. Furthermore, IGF-IDelta showed an inverse correlation with leptin Delta (rho = -0.398, P = 0.02).

CONCLUSIONS

In GHD children, the evaluation of metabolic parameters proves to be a useful tool for the evaluation of auxological parameters during GH replacement therapy. In our study, GH replacement therapy in GHD children improved final height, restored IGF-I levels, reduced leptin levels, and improved the lipid profile, without producing any unfavorable effects on glucose metabolism.

BRAFV600E mutation and p27kip1 expression in papillary carcinomas of the thyroid ≤1 cm and their paired lymph node metastases

BACKGROUND

BRAF(V600E) mutation and p27(kip1) expression have been introduced as novel indicators that may predict prognosis in different tumors, as well as in papillary thyroid carcinomas.

METHODS

Tissue samples from 214 consecutive patients who underwent total or near-total thyroidectomy with histological diagnosis of papillary thyroid carcinoma (PTC) <or=1 cm were analyzed for BRAF(V600E) mutation by a real-time, allele-specific amplification and for p27(kip1) expression by immunohistochemistry.

RESULTS

The BRAF(V600E) mutation was detected in 88 of the tumors examined, with significant differences between groups with and without lymph node (LN) metastases; the mean age of patients with BRAF(V600E) mutation was significantly higher than that of patients without mutations. A significant association was found between low p27(Kip1) protein expression and multifocality, bilaterality, and extrathyroidal extension, in addition to LN metastasis. In 42 cases with LN metastases, 23 harbored the BRAF(V600E) mutation in the metastatic tumor and presented a wider diameter of the largest metastatic area, a higher number of involved LNs, and a higher percentage of metastatic lesions with extracapsular extension of LN (ECE-LN). A significantly lower mean value of p27(Kip1) was observed in LNs harboring the BRAF(V600E) mutation and in ECE-LN; an inverse correlation was found between p27(Kip1) and the number of metastatic LNs, as well as the diameter of the largest metastatic area in LN.

CONCLUSIONS

The authors' data suggested that BRAF(V600E) mutation and p27(Kip1) down-regulation in cancer cells of PTC <or=1 cm may be factors that facilitate tumor-cell growth and progression once these are seeded in the LNs.

Lower insulin sensitivity differentiates hirsute from non-hirsute Sicilian women with polycystic ovary syndrome

OBJECTIVE

It is well known that hyperandrogenism and insulin-resistance with or without compensatory hyperinsulinism are closely associated, but the Rotterdam Consensus has concluded that principally obese women with polycystic ovary syndrome (PCOS) should be evaluated for the metabolic syndrome. Our aim was to study insulin sensitivity in PCOS women with hirsutism regardless of obesity.

METHODS

Clinical characteristics, sex hormones and fasting- and after OGTT-glycemia and insulinemia, homeostatic model of insulin resistance (HOMA IR), and Matsuda index of insulin sensitivity were analyzed in 130 women with PCOS. Hirsutism has been evaluated through the Ferriman-Gallwey (FG) map scoring system.

RESULTS

PCOS women with hirsutism (57.7% of participants) showed significant higher values of total testosterone levels (P = 0.016), free testosterone (P = 0.027), DHEA sulfate (P = 0.017), and Delta4androstenedione (P = 0.018). They had similar body mass index (BMI) (P = 0.073) and were significantly less insulin sensitive (P = 0.002) than those without hirsutism (42.3% of participants). In women with PCOS and hirsutism, there was a significant correlation between FG score and insulin-sensitivity indexes (HOMA IR, rho = 0.33, P = 0.005; Matsuda index, rho = -0.34, P = 0.003) but not with the androgen levels. Moreover, women with hirsutism showed a significantly greater insulin (P = 0.019), C-peptide (P = 0.002), and glucose (P = 0.024) areas under the curve (auc2h).

CONCLUSIONS

Our study suggests that the increased responsiveness of the pilo-sebaceous unit to androgens seems to be influenced by insulin sensitivity and that insulin resistance should be assessed in all hirsute women with PCOS regardless of their BMI, as insulin resistance was found in hirsute women irrespective of whether they were overweight or obese.

[Role of MR cholangiopancreatography in the evaluation of biliary disease]

PURPOSE

To evaluate the diagnostic accuracy of MR cholangiopancreatography (MRCP) in biliary tree patology in comparison with percutaneous transhepatic cholangiography (PTC), endoscopic retrograde cholangiopancreatography (ERCP) and surgical findings.

MATERIALS AND METHODS

Forty-six patients , with clinical and laboratory findings suggestive of biliary tree pathology, and after an abdominal US, underwent MRCP with a 1.5 T superconductive magnet equipped with a phased-array body coil. MR exam was performed with baseline sequences for the examination of the upper abdomen, followed by specific MRCP sequences and, in cases of suspected neoplastic disease, completed with abdominal sequences after a bolus injection of paramagnetic contrast.

RESULTS

MRCP showed normal findings in 16/46 patients, biliary duct dilatation in 25/46 patients (7 choledocolithiasis, 10 benign obstructions and 8 neoplastic stenoses) and stenoses without dilatation of biliary tree in 5/46 patients. In 25 patients with biliary duct dilatation, CPRM correctly identified the level of in 100% of patients (25/25) and the nature in 88% of patients (22/25). In 5 patients with stenosis without dilatation of biliary tree, CPRM identified 2 true positives (sclerosing cholangitis), 2 false positives and 1 patient is still in follow-up.

CONCLUSIONS

In our experience MRCP proved to be highly accurate as fundamental diagnostic step in patients with clinical and laboratory findings suggestive of biliary disease. The workload of ERCP, invasive method with risk of complications, in the diagnosis stage could therefore be reduced and its use be reserved for therapeutic indications.

Transient chylomicronemia preceding the onset of insulin-dependent diabetes in a young girl with no humoral markers of islet autoimmunity

OBJECTIVE

We investigated the possible causes of diabetes in a young child who presented with hyperglycemia associated with severe hypertriglyceridemia (>166 mmol/l), hypercholesterolemia (>38 mmol/l) and fasting chilomicrons.

RESULTS

The patient did not have any of the HLA and autoantibody markers typically associated with type 1 diabetes. A glucose clamp failed to demonstrate insulin resistance (peripheral glucose utilization rate (M)=4.3 mg/kg per min) and there was no family history of type 2 diabetes or maturity onset diabetes in youth. Both fasting and stimulated C-peptide levels, including those in response to i.v. glucagon, were below the limit of detection. This is consistent with loss of beta-cell function. The family history did not reveal the existence of relatives with lipid abnormalities, coronary heart disease, and pancreatitis. We did not find any abnormality of plasma apoCII, lipoproteinlipase and hepatic lipase activities. The patients had a epsilon3/epsilon3 apoE genotype and she rapidly cleared an oral fat load after normalization of plasma lipids.

CONCLUSIONS

The mild hyperglycemia seems an unlikely explanation for both the severe hypertriglyceridemia and chylomicronemia. A more plausible explanation is transient lipoproteinlipase deficiency. This rare condition, occasionally associated with a high-fat diet, could have caused the rapid and dramatic hypertriglyceridemia observed in this patient, which in turn might have led to the beta-cell destruction by direct lipid toxicity.

Up-regulation of c-FLIPshort and reduction of activation-induced cell death in T-cells from patients with Type 1 diabetes

AICD of T-cells is an efficient way of removing activated T-lymphocytes. In this study we investigated the molecular basis of AICD upon reactivation in peripheral T-lymphocytes from newly diagnosed T1DM patients and age-matched healthy controls. In an in vitro model system, PHA-stimulated T-cells, upon prolonged culture in IL-2, acquire a sensitive phenotype to Fas-mediated apoptosis. This phenomenon is less pronounced in T1DM T-cells. Moreover, the restimulation of activated T-cells via TCR/CD3 and/or via CD28 inhibits Fas-mediated apoptosis in T1DM in comparison to control T-cells. After Fas triggering, the generation of the active sub-units of caspase-8 is significantly reduced in T1DM T-cells restimulated via TCR/CD3 and/or CD28. In parallel, we found that the amount of c-FLIPshort protein is significantly increased in the DISC only in T1DM T-cells restimulated via TCR/CD3 and via CD28. These data suggest that increased levels of c-FLIPshort may prevent recruitment of pro-caspase-8 in T1DM CD3-treated T-cells and provide new insight into the molecular mechanisms of apoptosis resistance in stimulated T-cells from T1DM patients.

Importance of premeal injection time in insulin therapy: Humalog Mix25 is convenient for improved post-prandial glycemic control in type 2 diabetic patients with Italian dietary habits

We investigated the use, in a short period, of Humalog Mix25 (Mix25) in a twice-daily administration regimen compared to a twice-daily injection therapy with Humulin 30/70 (30/70) in diabetic patients with Italian dietary habits. We studied 33 type 2 diabetic patients aged 59.1 +/- 8.1 years, BMI 29.8 +/- 2.7 kg/m2, duration of diabetes and insulin therapy of 14.4 +/- 9.8 and 4.2 +/- 4.6 years, respectively. After a 4-day lead-in period of twice-daily human insulin 30/70 treatment, patients were randomized to one of two treatment sequences: (1) a twice-daily regimen with Mix25 just 5 minutes before the morning and evening meals for 12 days, followed by a twice-daily therapy with human insulin 30/70 given 30 minutes before the morning and evening meals for an additional 12 days; or (2) the alternate sequence. Each patient underwent a mixed meal test: Humulin 30/70 was administered 30 minutes before the meal, while Mix25 was given 5 minutes before. The 2-hour post-prandial glucose concentration after breakfast was significantly lower during treatment with Mix25 than with Humulin 30/70 (157 +/- 43.2 vs. 180 +/- 43.2 mg/dl, p<0.05). The glycemic excursion after dinner on Mix25 treatment was significantly lower than with Humulin 30/70 (12.2 +/- 48.01 vs. 35.5 +/- 36.92 mg/dl, p<0.05). AUCglucose after Mix25 was lower than after Humulin 30/70. Glycemia after test meal was significantly lower with Mix25 than with Humulin 30/70. Insulin and free insulin concentrations after the test meal were significantly higher with Mix25 in comparison to Humulin 30/70. AUC serum insulin and free insulin curves after Mix25 were significantly higher than after Humulin 30/70 (p=0.028 and p=0.005, respectively). Twice-daily injections of Humalog Mix25, compared to human insulin 30/70 in type 2 diabetic patients with Italian dietary habits, provide improved and lasting post-prandial glycemic control, with the great convenience of the injection just before the meal.

Regulation of apoptosis in endocrine autoimmunity: insights from Hashimoto's thyroiditis and Graves' disease

Dysregulation of apoptosis is associated with the pathogenesis of organ-specific autoimmune diseases, through altered target organ susceptibility. Apoptosis signaling pathways can be initiated through activation of death receptors such as Fas. A comparative analysis of the expression of Fas and FasL, the antiapoptotic molecule Bcl-2, and apoptosis in both thyrocytes and thyroid-infiltrating lymphocytes (TILs) from patients with either Graves' disease (GD) or Hashimoto's thyroiditis (HT) was performed. GD thyrocytes expressed less Fas than HT thyrocytes, whereas GD TILs had higher levels of Fas and FasL than HT TILs. GD thyrocytes expressed higher levels of Bcl-2 compared with HT thyrocytes. The opposite pattern was observed in GD (low Bcl-2) and HT (high Bcl-2) TILs. Consistently, thyrocyte apoptosis was marked in HT and poor in GD thyroids, and TIL apoptosis was marked in GD and poor in HT. Our findings suggest that in GD thyroid the regulation of Fas/FasL/Bcl-2 favors apoptosis of infiltrating lymphocytes. Moreover, the reduced levels of Fas/FasL and increased levels of Bcl-2 should favor thyrocyte survival and hypertrophy associated with stimulatory thyroid-stimulating hormone receptor antibodies. In contrast, the regulation of Fas/FasL/Bcl-2 expression in HT can promote thyrocyte apoptosis via homophylic Fas-FasL interactions, and a gradual reduction in thyrocyte numbers leading to hypothyroidism. Fas-mediated apoptosis may be a general mechanism of cell damage in destructive organ-specific autoimmunity.

Preprandial combination of lispro and NPH insulin improves overall blood glucose control in type 1 diabetic patients: a multicenter randomized crossover trial

BACKGROUND AND AIM

While lispro insulin has been reported to lower postprandial blood glucose concentrations, less consistent effects have been shown for glycosylated hemoglobin (HbA1c) levels. Aim of this study was to determine whether pre-meal association of NPH, an intermediate-acting insulin, with lispro improves overall glycemic control in type 1 diabetic patients.

METHODS AND RESULTS

Eighty-five type 1 diabetic patients were studied in a multicenter randomized comparative (human regular vs lispro insulin) crossover (3-month) study in which NPH insulin was given as a dinner or bedtime injection and at breakfast and lunch if necessary. The number of injections was kept constant: 42% and 58% of patients injected insulin 3 and 4 times per day, respectively. Fasting and preprandial blood glucose levels were similar, while postprandial levels improved after lispro compared to human regular insulin (breakfast: 8.28 +/- 2.39 vs 9.28 +/- 2.72 mmol/l; lunch: 8.33 +/- 2.67 vs 9.06 +/- 2.67 mmol/l, dinner: 8.06 +/- 2.72 vs 9.28 +/- 2.44 mmol/l, ANOVA: p = 0.003). HbA1c also improved after lispro: 8.1 +/- 0.9 vs 8.3 +/- 0.8%, p < 0.05. The rate of hypoglycemia was similar. Patients showed better acceptance of lispro treatment (p < 0.001).

CONCLUSIONS

Lispro improves overall blood glucose control in type 1 diabetic patients without increasing the incidence of hypoglycemia. This can be achieved by an optimal combination of lispro insulin with NPH whenever the time intervals between meals are too long.

Cytokine profiles in drug-naive schizophrenic patients

A large body of evidence concerning immunological abnormalities in schizophrenic patients seems to suggest a role of the immune system in the multifactorial pathogenesis of schizophrenia. We investigated the production of various cytokines [interleukin (IL)-2, IL-4, IL-10, interferon (INF)-gamma] in drug-free (n=26) and drug-naive (n=7) schizophrenic patients and in healthy controls (n=33). Production of IL-2 and INF-gamma was significantly higher (respectively P=0.021 and P=0.001) in patients than in controls. These findings provide further evidence that immunological abnormalities are present in some schizophrenic patients.

Differential regulation of Fas-mediated apoptosis in both thyrocyte and lymphocyte cellular compartments correlates with opposite phenotypic manifestations of autoimmune thyroid disease

Several mechanisms are probably involved in determining the evolution of autoimmune thyroid disease (AITD) towards either hypothyroidism and the clinical syndrome known as Hashimoto's thyroiditis (HT) or toward hyperthyroidism and the symptoms of Graves' disease (GD). To gain further insight into such mechanisms we performed an exhaustive comparative analysis of the expression of key molecules regulating cell death (Fas, Fas ligand [FasL], Bcl-2) and apoptosis in both thyrocytes and thyroid infiltrating lymphocytes (TILs) from patients with either GD or HT. GD thyrocytes expressed less Fas/FasL than HT thyrocytes, whereas GD TILs had higher levels of Fas/FasL than HT TILs. GD thyrocytes expressed increased levels of the antiapoptotic molecule Bcl-2 compared to the low levels detected in HT thyrocytes. The opposite pattern was observed in GD (low Bcl-2) and HT (high Bcl-2) TILs. The patterns of apoptosis observed were consistent with the regulation of Fas, FasL, and Bcl-2 described above. Our findings suggest that in GD thyroid the regulation of Fas/FasL/Bcl2 favors apoptosis of infiltrating lymphocytes, possibly limiting their autoreactive potential and impairing their ability to mediate tissue damage. Moreover, the reduced levels of Fas/FasL and increased levels of Bcl-2 should favor thyrocyte survival and favor the thyrocyte hypertrophy associated with immunoglobulins stimulating the thyrotropin (TSH) receptor. In contrast, the regulation of Fas/FasL/Bcl2 expression in HT promotes thyrocyte apoptosis, tissue damage, and a gradual reduction in thyrocyte numbers leading to hypothyroidism. These findings help define key molecular mechanisms contributing to the clinical outcome of thyroid autoimmunity.

Possible pathogenetic relevance of interleukin-1 beta in "destructive" organ-specific autoimmune disease (Hashimoto's thyroiditis)

Thyroid follicular cells (TFC) abundantly express a variety of immunologically relevant surface molecules in Hashimoto's thyroiditis (HT), for example, MHC antigens and adhesion molecules such as ICAM-1. Cytokines produced by infiltrating type 1 helper and cytotoxic T cells are importantly involved in de novo expression or up-regulation of such molecules. We recently demonstrated that TFC from HT patients almost invariably bear on their surface two additive functional molecules: Fas/Apo1/CD95, an important participant in apoptosis, and B7.1, a member of a family of "co-stimulatory" molecules that are crucial for efficient antigen presentation. To date, 12 out of 14 surgical HT thyroid specimens that we studied by immunohistochemistry showed B7.1-positive TFC, and all showed Fas-positive TFC, different from Graves' disease (GD) or nonautoimmune specimens. We have investigated the role of a number of cytokines (IL-1 beta, TNF-alpha, IL-4, IL-6, IL-10, IL-12, TGF-beta 1, IFN-gamma) in regulating B7.1 and Fas expression. The experiments were performed by immunofluorescence flow cytometry on TFC purified from nontoxic goiter specimens which were Fas- and B7.1-negative at baseline, and one B7.1/Fas-positive HT specimen. IFN-gamma (500 U/mL) and TNF-alpha (200 ng/mL) were unable to induce de novo expression of B7.1 or Fas on cultured TFC. At higher doses (2000 U/mL and 800 ng/mL, respectively), they were unable to induce B7.1, but potentiated the spontaneous expression of Fas. Type 2 cytokines (IL-4 and IL-10) were unable to induce Fas or B7.1 on TFC at all, or to down-regulate Fas or B7.1 when expressed. On the other hand, IL-1 beta was the only cytokine able to induce Fas expression on Fas-negative TFC at doses ranging from 100 to 1000 pg/mL. Moreover, at a dose of 400 pg/mL, it was also able to induce B7.1. We demonstrated by immunohistochemistry that IL-1 beta is abundantly present on HT thyroids, including follicular structures. It is conceivable that IFN-gamma, or other cytokines secreted by infiltrating T-lymphocytes, are able to promote IL-1 beta secretion by TFC. In conclusion, a crucial role of IL-1 beta in "destructive" organ-specific autoimmunity may be suggested both for the perpetuation of the autoimmune reaction (induction of efficient autoantigen presentation by TFC, via co-stimulatory molecules) and in induction of tissue damage via "suicide" Fas/FasL-mediated TFC interaction.

Nitric oxide primes pancreatic beta cells for Fas-mediated destruction in insulin-dependent diabetes mellitus

Fas is an apoptosis-inducing surface receptor involved in controlling tissue homeostasis and function at multiple sites. Here we show that beta cells from the pancreata of newly diagnosed insulin-dependent diabetes mellitus (IDDM) patients express Fas and show extensive apoptosis among those cells located in proximity to Fas ligand-expressing T lymphocytes infiltrating the IDDM islets. Normal human pancreatic beta cells that do not constitutively express Fas, become strongly Fas positive after interleuken (IL)-1beta exposure, and are then susceptible to Fas-mediated apoptosis. NG-monomethyl-L-arginine, an inhibitor of nitric oxide (NO) synthase, prevents IL-1beta-induced Fas expression, whereas the NO donors sodium nitroprusside and nitric oxide releasing compound (NOC)-18, induce functional Fas expression in normal pancreatic beta cells. These findings suggest that NO-mediated upregulation of Fas contributes to pancreatic beta cell damage in IDDM.

Defective expression of CD95 (FAS/APO-1) molecule suggests apoptosis impairment of T and B cells in HLA-B8, DR3-positive individuals

Activation-induced apoptosis is one of the primary control mechanisms for the negative selection of an immune response, leading to maintenance of immune homeostasis and selective T cell deletion. The interaction between the surface molecule Fas and its ligand (FasL) has been proposed as a primary mechanism initiating T cell apoptosis. The T cell receptor modulates the expression and function of these molecules. Defects in the Fas/FasL apoptosis pathway have been shown to result in autoimmune disease in humans and in murine models. Because subjects carrying the HLA-B8, DR3 haplotype show a number of immune dysfunctions, including membrano-proliferative glomerulonephritis, systemic lupus erythematosus, Graves' disease, and others, we investigated Fas expression on T and B cells, and sensitivity to Fas-mediated apoptosis of activated T cells, to determine whether abnormalities of the Fas pathway might be associated with the development of autoimmune diseases in this group of individuals. Our findings show that B cells and resting T cells from HLA-B8+, DR3+ subjects express markedly reduced levels of Fas compared with those isolated from HLA-B8-, DR3+ individuals. Reduced levels of Fas were also evident on the surface of T cells from HLA-B8+, DR3+ subjects activated in vitro by stimulation with OKT3 and phytohemoagglutinin. Cycling T cells from these subjects, evaluated for apoptotic nuclei by flow cytometry after incubation with a cytolytic anti-Fas mAb, showed a significantly lower percentage of Fas-mediated apoptosis than did those from HLA-B8-, DR3- individuals. Normal levels of apoptosis were restored after exposure to a synthetic ceramide analog (C2). Further elucidation of the interaction of these molecules in autoimmune diseases may lead to better understanding of the pathogenesis of these disorders.

Influences of obesity and weight loss on thyroid hormones. A 3-3.5-year follow-up study on obese subjects with surgical bilio-pancreatic by-pass

The effects of changing body size, energy intake and substrate oxidation on serum T4, FT4, T3, FT3 and TSH were investigated in ten morbidly obese subjects (4 men/6 women; age: 37 +/- 6 years; BMI: 53.8 +/- 6.5 kg/m2; mean +/- SD) who had undergone a surgical bilio-pancreatic by-pass in order to reduce their body weight. The starting value of serum FT3 was inversely related to the BMI (r = -0.63; p < 0.05). After 1-3 months, all the subjects were losing weight and their intake of carbohydrates was almost negligible; at this time a significant reduction of T3 (-14.6%; p < 0.0001), T4 (-19.5%; p < 0.0001), and FT3 (-10.5%; p < 0.001) was observed. Nine to 16 months after surgery, all the subjects were still losing weight, although there was no carbohydrate restriction; T3, T4, and FT3 were lower than prior to surgery but were beginning to increase. Finally, after 36-42 months the body weight of all the patients had been stable for at least the previous six months (final BMI: 32.9 +/- 4.1) and their body composition, as assessed by bio-impedance, was almost normal; only the concentrations of FT3 proved to be significantly lower than the basal value (-11.2%; p < 0.03). The change in FT3 proved to be independently influenced by the degree of fat malabsorption but not by changes in any of the physical characteristics considered. All values were always in the normal range; FT4 and TSH did not change significantly during the whole period of study. The final concentrations of TSH proved to be independently related to the postabsorptive protein oxidation (g/24h) (TSH = 2.37-0.018* protein oxidation). These results would suggest that nutritional factors have some influence on the blood levels of thyroid hormones, especially of FT3, while the removal of obesity does not seem to have any independent effect in the long-run.

Potential involvement of Fas and its ligand in the pathogenesis of Hashimoto's thyroiditis

The mechanisms responsible for thyrocyte destruction in Hashimoto's thyroiditis (HT) are poorly understood. Thyrocytes from HT glands, but not from nonautoimmune thyroids, expressed Fas. Interleukin-1beta (IL-1beta), abundantly produced in HT glands, induced Fas expression in normal thyrocytes, and cross-linking of Fas resulted in massive thyrocyte apoptosis. The ligand for Fas (FasL) was shown to be constitutively expressed both in normal and HT thyrocytes and was able to kill Fas-sensitive targets. Exposure to IL-1beta induced thyrocyte apoptosis, which was prevented by antibodies that block Fas, suggesting that IL-1beta-induced Fas expression serves as a limiting factor for thyrocyte destruction. Thus, Fas-FasL interactions among HT thyrocytes may contribute to clinical hypothyroidism.

Depression of CD4 T cell subsets and alteration in cytokine profile in boutonneuse fever

Interferon (IFN)-gamma, interleukin (IL)-10, IL-6, and tumor necrosis factor (TNF)-alpha were significantly increased in sera from Sicilian patients with acute boutonneuse fever (BF) compared with those of healthy controls. IFN-gamma levels dropped sharply within the second week after infection. IL-6, IL-10, and TNF-alpha levels gradually declined; in convalescent patients only were they in the normal range. In contrast, peripheral blood mononuclear cells (PBMC) stimulated in vitro with phytohemagglutinin (PHA) produced low levels of IL-10 and IFN-gamma in acute BF that were compatible with the reduction in the levels of CD4+, CD4+/CD45RO+, and CD4+/CD45RA+ cells. In vitro production of TNF-alpha and IL-6 from PBMC stimulated with PHA was not significantly modified during the various phases of the infection compared with control PBMC, which could be due to the persistence of high levels of CD14+ monocytes compensating for the decrease in CD20+ B cells.

[Pancreatic harvesting from multiorgan donors for islet transplantation]

The result of human islet isolation procedures to transplant in type I insulin-dependent diabetic patients is significantly conditioned by the technique used for pancreas procurement from multiorgan donor. In fact, during multiorgan procurement, an improper handling of the gland could result in edema or degranulation of the acinar tissue, detrimental for the islet purification step. The surgical technique used by our surgical team, includes some important refinements to obtain the largest quantity and the best quality of purified endocrine material.