Liver involvement in essential mixed cryoglobulinemia

Summary Twenty-one of 30 patients with essential mixed cryoglobulinemia (EMC) had evidence of liver involvement. The liver disease was characterized by the absence of clinical symptoms, hepatosplenomegaly, mild elevation of enzymes, abnormal BSP retention and low albumin levels. Histology, available in 12 patients, showed either chronic persistent or chronic active hepatitis or liver cirrhosis; 44% of the patients had HBsAg or HBsAb in sera and/or cryoglobulins, confirming the high frequency of exposure to hepatitis B virus (HBV) infection in EMC. However, liver lesions were similar in all patients, regardless of HBV exposure. Since other factors usually associated with chronic liver diseases were absent or apparently irrelevant, it is temptative to speculate that a ‘cryoglobulinemic hepatitis’ may exist as a distinct syndrome. The characteristic complement profile of the patients with EMC (low CH₅₀ and C4, normal C3PA), not related to albumin levels, can help to differentiate this disease from chronic liver disease without cryoglobulins. A preliminary report of this work was presented at the XIV International Congress of Rheumatology, San Francisco, Calif., USA, on June 27, 1977.     

Possible roles of insulin,glucagon, growth hormone and free fatty acids in the pathogenesis of insulin resistance of subjects with chronic liver diseases

Summary In the present investigation, insulin sensitivity and fasting levels of insulin, C-peptide, glucagon, growth hormone and free fatty acids were estimated and correlated in a population of individuals suffering from liver cirrhosis or chronic hepatitis. Insulin sensitivity, assessed by glucose disappearance rate after intravenous bolus injection of insulin, was reduced but not significantly different from controls in subjects with chronic persistent hepatitis, while it was significantly reduced in individuals suffering from chronic active hepatitis or liver cirrhosis. Insulin, glucagon, growth hormone, and free fatty acid fasting levels were higher than in healthy subjects in individuals with liver cirrhosis or chronic active hepatitis but not in subjects with chronic persistent hepatitis. C-peptide concentrations did not differ from controls in subjects with liver disease. Significant negative correlations occurred between coefficients of insulin sensitivity and fasting concentrations of insulin, glucagon, growth hormone and free fatty acids, but not with fasting levels of C-peptide. Positive relationships were present between fasting levels of free fatty acids and both glucagon and growth hormone concentrations. These results show that, unlike subjects with liver cirrhosis and chronic active hepatitis, individuals suffering from chronic persistent hepatitis do not differ from healthy subjects in insulin sensitivity and fasting levels of insulin, glucagon, growth hormone, and free fatty acids. Moreover, they suggest that both hyperinsulinemia and high concentrations of counterregulatory substances might play a role in the pathogenesis of insulin resistance in subjects suffering from chronic liver disease. Supported by grants from the Ministry of Public Education and grant No. 83/02132.04 from the National Research Council (C.N.R.), Rome.     

Mixed binary-continuous copula regression models with application to adverse birth outcomes

Bivariate copula regression allows for the flexible combination of two arbitrary, continuous marginal distributions with regression effects being placed on potentially all parameters of the resulting bivariate joint response distribution. Motivated by the risk factors for adverse birth outcomes, many of which are dichotomous, we consider mixed binary-continuous responses that extend the bivariate continuous framework to the situation where one response variable is discrete (more precisely, binary) whereas the other response remains continuous. Utilizing the latent continuous representation of binary regression models, we implement a penalized likelihood–based approach for the resulting class of copula regression models and employ it in the context of modeling gestational age and the presence/absence of low birth weight. The analysis demonstrates the advantage of the flexible specification of regression impacts including nonlinear effects of continuous covariates and spatial effects. Our results imply that racial and spatial inequalities in the risk factors for infant mortality are even greater than previously suggested.     

Incidence and clinical predictors of primary opportunistic deep cutaneous mycoses in solid organ transplant recipients: a multicenter cohort study

Tessari G, Naldi L, Piaserico S, Boschiero L, Nacchia F, Forni A, Rugiu C, Faggian G, Dall’Olio E, Fortina AB, Alaibac M, Sassi F, Gotti E, Fiocchi R, Fagioli S, Girolomoni G. Incidence and clinical predictors of primary opportunistic deep cutaneous mycoses in solid organ transplant recipients: a multicenter cohort study.
Clin Transplant 2010: 24: 328–333. © 2009 John Wiley & Sons A/S. Abstract: Background: Primary opportunistic deep cutaneous fungal
infections may cause significant morbidity and mortality in solid organ transplant recipients (OTR), but no data exist about their incidence, timing, and clinical predictors in a long‐term follow‐up. Patients and methods: A series of 3293 consecutive OTR including 1991 kidney, 929 heart, and 373 liver transplant recipients were enrolled. Patients were regularly followed up since time at transplantation (mean 5.5 yr ±5.9 SD) and primary opportunistic fungal infections registered. Persons‐year at risk (PYs), incidence rates (IR), incidence rate ratios (IRR), and 95% confidence intervals were computed. Results: Twenty‐two cases of deep cutaneous mycoses were detected, (IR 1.2 cases per 1000 PYs) after a mean follow‐up time since transplantation of 2.5 yr ± 2.0 SD (median 1.8 yr). Six patients had subsequent systemic involvement and three patients died of systemic dissemination. A higher risk for mycoses was observed in the first two yr after transplantation, (IRR 35.9, p < 0.0001), in renal transplant recipients (IRR 5.1 p = 0.030), and in patients transplanted after the age of 50 (IRR 11.5 p = 0.020). Conclusions: Primary deep cutaneous opportunistic mycoses in OTR occur mainly in the first two yr after transplantation, in renal transplant recipients, and in older patients.     

Toll-like receptors (TLRs) in innate immune defense against Staphylococcus aureus

Toll-like receptors (TLRs) are the most important class of innate pattern recognition receptors (PRRs) by which host immune and non-immune cells are able to recognize pathogen-associated molecular patterns (PAMPs). Most mammalian species have 10 to 15 types of TLRs. TLRs are believed to function as homo- or hetero-dimers. TLR2, which plays a crucial role in recognizing PAMPs from Staphylococcus aureus, forms heterodimers with TLR1 or TLR6 and each dimer has a different ligand specificity. Staphylococcal lipoproteins, Panton-Valentine toxin and Phenol Soluble Modulins have been identified as potent TLR2 ligands. Conversely, the ligand function attributed to peptidoglycan and LTA remains controversial. TLR2 uses a MyD88-dependent signaling pathway that results in NF-kB translocation into the nucleus and activation of the expression of pro-inflammatory cytokine genes. Recognition rouses both an inflammatory response, culminating in the phagocytosis of bacteria, and an adaptive immune response, with the presentation of resulting bacterial compounds to T cells. Here, recent advances on the recognition of S. aureus by TLRs are presented and discussed, as well as the new therapeutic opportunities deriving from this new knowledge.     

Reduced hippocampal 5HT1A PET receptor binding and depression in temporal lobe epilepsy

Summary:  Purpose: To study the relation of hippocampal 5HT1A receptor binding to symptoms of depression in patients with temporal lobe epilepsy. Depression is common in people with epilepsy, and reduced 5HT1A binding has been reported in patients with primary depressive disorders.
Methods: We studied 45 patients with temporal lobe epilepsy confirmed by ictal video-EEG recording. Mood was assessed with the Beck Depression Inventory (BDI). Positron emission tomographic measurement of 5HT1A receptors was performed with 18F-FCWAY, a highly specific silent antagonist. 3D-T1-weighted MRI was used to correct for structural atrophy. Receptor distribution volume (V) was corrected for plasma tracer free fraction (f1).
Results: There was a significant inverse relation between ipsilateral hippocampal v/f1 and the BDI. For contralateral hippocampus, there was a nonsignificant trend. Patients with BDI > 20 had significantly lower ipsilateral hippocampal V/f1 than patients in the low and medium groups. There was no significant effect of the presence of mesial temporal sclerosis, focus laterality, or gender on the BDI.
Conclusions: Our study shows a relationship between hippocampal 5HT1A binding and depressive symptoms measured by the BDI in patients with epilepsy. The findings parallel results in patients with MDD.     

Oral Specific Desensitization in Food-Allergic Children

The possibility of obtaining oral desensitization in patients with food allergy is still a matter of debate. We decided to evaluate the safety and efficacy of standardized protocols for oral desensitization with the most common food allergens. Forty-two children (ages up to 16 years) diagnosed as affected by food allergy (on the basis of clinical history, skin prick tests, measurement of specific IgE, and double-blind, placebo-controlled food challenge) underwent a sublingual-oral desensitizing treatment according to new standardized protocols. The control group consisted of 10 patients who followed an elimination diet. The treatment was successfully completed by 85.7% of the patients. Specific IgE showed a significant decrease, while specific IgG₄ showed a significant increase, in all treated patients. The immunological modifications observed in our patients lead us to hypothesize that oral tolerance may be mediated by the same mechanisms as those involved in traditional desensitizing treatments for respiratory and insect sting allergy.     

Acylated and unacylated ghrelin promote proliferation and inhibit apoptosis of pancreatic beta-cells and human islets: involvement of 3',5'-cyclic adenosine monophosphate/protein kinase A, extracellular signal-regulated kinase 1/2, and phosphatidyl inositol 3-Kinase/Akt signaling

Among its pleiotropic actions, ghrelin modulates insulin secretion and glucose metabolism. Herein we investigated the role of ghrelin in pancreatic beta-cell proliferation and apoptosis induced by serum starvation or interferon (IFN)-gamma/TNF-alpha, whose synergism is a major cause for beta-cell destruction in type I diabetes. HIT-T15 beta-cells expressed ghrelin but not ghrelin receptor (GRLN-R), which binds acylated ghrelin (AG) only. However, both unacylated ghrelin (UAG) and AG recognized common high-affinity binding sites on these cells. Either AG or UAG stimulated cell proliferation through Galpha(s) protein and prevented serum starvation- and IFN-gamma/TNF-alpha-induced apoptosis. Antighrelin antibody enhanced apoptosis in either the presence or absence of serum but not cytokines. AG and UAG even up-regulated intracellular cAMP. Blockade of adenylyl cyclase/cAMP/protein kinase A signaling prevented the ghrelin cytoprotective effect. AG and UAG also activated phosphatidyl inositol 3-kinase (PI3K)/Akt and ERK1/2, whereas PI3K and MAPK inhibitors counteracted the ghrelin antiapoptotic effect. Furthermore, AG and UAG stimulated insulin secretion from HIT-T15 cells. In INS-1E beta-cells, which express GRLN-R, AG and UAG caused proliferation and protection against apoptosis through identical signaling pathways. Noteworthy, both peptides inhibited cytokine-induced NO increase in either HIT-T15 or INS-1E cells. Finally, they induced cell survival and protection against apoptosis in human islets of Langerhans. These expressed GRLN-R but showed also UAG and AG binding sites. Our data demonstrate that AG and UAG promote survival of both beta-cells and human islets. These effects are independent of GRLN-R, are likely mediated by AG/UAG binding sites, and involve cAMP/PKA, ERK1/2, and PI3K/Akt.     

Multiple-dose pharmacokinetics of efavirenz with and without the use of rifampicin in HIV-positive patients

Rifampicin (RIF) decreases serum concentrations of several antiretroviral drugs. We carried out a prospective, comparative study to define efavirenz (EFV) pharmacokinetics in 16 cases and 13 controls. Cases were HIV and tuberculosis (TB) co-infected adults assuming RIF 600 mg once daily and EFV 800 mg once daily. Patients on EFV at standard 600 mg dose without RIF were taken as controls. EFV levels in plasma were assayed by high-performance liquid chromatography (HLPC) predose (C(trough)) and at 1, 2, 3, 4, 5, 6, 8, 10, 11, 12, 13, 14, 16, 18, 22 and 24 hours post-dose, and pharmacokinetic parameters were determined by non-compartmental methods. Among cases, 81% were males, mean age was 37 years, 50% were Caucasians, mean weight was 64 kg, mean CD4 cell counts and log HIV RNA copies were 160/microl and 5.2 /microl, respectively. Cases had a significantly higher Cl/F/kg if compared with controls (0.269 +/- 0.12 versus 0.167 + 0.05 L/h/kg, p<0.01). Otherwise, dose-dependent pharmacokinetic parameters of EFV were similar between cases and controls. Interindividual variability was consistently higher among TB cases compared to controls for all considered parameters. All cases completed combined treatment and no increased EFV toxicity was observed. These results suggest that a dose of 800 mg of EFV in association with rifampicin may be appropriate for patients of weight > 60 kg in Europe. Therapeutic drug monitoring may be beneficial for patients on combination therapy with RIF.