Effect of intravenous immunoglobulin treatment on the Th1/Th2 balance in women with recurrent spontaneous abortions

PROBLEM: The way by which intravenous immunoglobulin (IvIg) acts to prevent immunlogically mediated recurrent spontaneous abortions (RSA) has not been clarified. In the present study, a possible effect of IvIg on the T helper cell (Th1/Th2) balance was investigated in abortions of either alloimmune or autoimmune abnormalities. METHOD OF STUDY: The study included 21 women treated with IvIg before conception because of a history of RSA characterized by alloimmune abnormalities (n = 15) or associated with anti-phospholipid antibodies (APA) (n = 6). Peripheral blood samples, collected before and 5 days after the first IvIg infusion, were stimulated, and Th1 and Th2 cells were detected by flow-cytometric analysis using a combination of monoclonal antibodies against T-cell surface markers and intracellular interferon (IFN)-gamma and interleukin (IL)-4. The percentage of IFN-gamma-producing (Th1) and IL-4-producing (Th2) cells and the Th1/Th2 ratio were compared between pre- and post-infusion samples. RESULTS: A decrease of Th1 percentage in 66.6% of the cases and a concurrent Th2 percentage increase (47.61%) resulted in a decrease in the Th1/Th2 ratio in most of the cases (76.1%) (p < 0.01). Similar results were found in Group A (Th1/Th2 decreased in 60% of the cases, p < 0.05), while in Group B the effect of IvIg was not clear (Th1/Th2 increased in three and decreased in another three cases). CONCLUSION: Our finding suggests that IvIg administration in women with alloimmune RSA enhances Th2 polarization. This is not always the case with APA-associated abortions.     

Melanin-concentrating hormone regulates leptin synthesis and secretion in rat adipocytes

Obesity is a common problem in Western society and is associated with significant morbidity and mortality. Energy homeostasis is regulated by a complex system involving both peripheral signals such as leptin and a number of orexigenic and anorectic neuropeptides. Obesity can result from dysregulation of the peripheral and/or central signals. Melanin-concentrating hormone (MCH) is a hypothalamic peptide that is important in the regulation of feeding behavior, primarily via uncharacterized signaling pathways in the central nervous system. Leptin, expressed in adipose tissue, mediates some of its actions through several hypothalamic neuropeptides, notably agouti-related peptide, proopiomelanocortin, and neuropeptide Y. Expression of leptin is regulated by dietary status, insulin, and glucocorticoids. Furthermore, certain neuropeptides may act on adipocytes. However, the potential effect of MCH has not been investigated. We report that MCH stimulates leptin mRNA expression and leptin secretion. MCH stimulated a 2-fold increase in leptin secretion by isolated rat adipocytes after 4 h of treatment. This increase in secreted leptin was preceded by a rapid and transient increase in ob mRNA levels; MCH stimulated a 2.5-fold increase in ob mRNA within 1 h of treatment, followed by a decline to basal levels within 4 h. In addition, we demonstrate that the MCH receptor SLC-1 is expressed in adipocytes, suggesting that fat cells may be targets of MCH or an MCH-like peptide under physiological conditions. Finally, using a radioimmunoassay, MCH/MCH-like peptide was detected in rat plasma. This study establishes a novel in vitro mammalian system for examining MCH signaling pathways.     

High‐frequency p16INK4A promoter methylation is associated with histone methyltransferase SETDB1 expression in sporadic cutaneous melanoma

Epigenetic mechanisms participate in melanoma development and progression. The effect of histone modifications and their catalysing enzymes over euchromatic promoter DNA methylation in melanoma remains unclear. This study investigated the potential association of p16^INK4A promoter methylation with histone methyltransferase SETDB1 expression in Greek patients with sporadic melanoma and their correlation with clinicopathological characteristics. Promoter methylation was detected by methylation‐specific PCR in 100 peripheral blood samples and 58 melanoma tissues from the same patients. Cell proliferation (Ki‐67 index), p16^INK4A and SETDB1 expression were evaluated by immunohistochemistry. High‐frequency promoter methylation (25.86%) was observed in tissue samples and correlated with increased cell proliferation (P = 0.0514). p16^INK4A promoter methylation was higher in vertical growth‐phase (60%) melanomas than in radial (40%, P = 0.063) and those displaying epidermal involvement (P = 0.046). Importantly, p16^INK4A methylation correlated with increased melanoma thickness according to Breslow index (P = 0.0495) and marginally with increased Clark level (I/II vs III/IV/V, P = 0.070). Low (1–30%) p16^INK4A expression was detected at the majority (19 of 54) of melanoma cases (35.19%), being marginally correlated with tumor lymphocytic infiltration (P = 0.078). SETDB1 nuclear immunoreactivity was observed in 47 of 57 (82.46%) cases, whereas 27 of 57 (47.37%) showed cytoplasmic immunoexpression. Cytoplasmic SETDB1 expression correlated with higher frequency of p16^INK4A methylation and p16^INK4A expression (P = 0.033, P = 0.011, respectively). Increased nuclear SETDB1 levels were associated with higher mitotic count (0–5/mm² vs >5/mm², P = 0.0869), advanced Clark level (III‐V, P = 0.0380), epidermal involvement (P = 0.0331) and the non‐chronic sun exposure‐associated melanoma type (P = 0.0664). Our data demonstrate for the first time the association of histone methyltransferase SETDB1 with frequent methylation of the euchromatic p16^INK4A promoter and several prognostic parameters in melanomas.     

Methodological Challenges in Online Trials

Health care and health care services are increasingly being delivered over the Internet. There is a strong argument that interventions delivered online should also be evaluated online to maximize the trial’s external validity. Conducting a trial online can help reduce research costs and improve some aspects of internal validity. To date, there are relatively few trials of health interventions that have been conducted entirely online. In this paper we describe the major methodological issues that arise in trials (recruitment, randomization, fidelity of the intervention, retention, and data quality), consider how the online context affects these issues, and use our experience of one online trial evaluating an intervention to help hazardous drinkers drink less (DownYourDrink) to illustrate potential solutions. Further work is needed to develop online trial methodology.     

A 10-year aerobiological study (1994-2003) in the Mediterranean island of Crete, Greece: trees, aerobiologic data, and botanical and clinical correlations.

Pollen grains from the plant cover of a given area participate largely in the composition of aeroflora (pollen and molds) of this area. Association of allergic respiratory disorders with concentration of allergenic particles in the atmosphere is well documented, and aerobiologic studies are of great relevance. A 10-year volumetric aerobiologic study was conducted in the city of Heraklion, located in the center of the north-shore of the island of Crete, Greece. Main allergenic families and genera encountered were, in descending order of frequency Oleaceae, Quercus, Platanaceae, Cupressaceae, Pinaceae, Populus, Moraceae, and Corylaceae. Concentrations noted for most of these aeroallergens were much lower than those reported from other European regions. In parallel, an atopic population of 576 individuals, exhibiting allergic symptoms mainly of the respiratory tract were subjected to a battery of skin-prick tests. A fair degree of agreement between total pollen counts and positive skin-prick test frequencies for the families of Oleaceae, Platanaceae, and Cupressaceae was noted. On the contrary a poor degree of concordance was noted for the rest of the families and genera.