Risk factors for psoriasis: A case–control study

A case–control study of 110 consecutive psoriatic outpatients and 200 unmatched controls was carried out in order to analyze the association of psoriasis with smoking habits, alcohol consumption, family history of psoriasis and stressful life events. Stressful life events were assessed with Paykel's Interview for Recent Life Events, a semi-structured interview covering 63 life events. According to our results, the risk of psoriasis is higher in urban dwellers (odds ratio [OR] = 3.61; 95% confidence interval [CI] = 0.99–13.18), patients who were divorced (OR = 5.69; 95% CI = 2.26–14.34) and those exposed to environmental tobacco smoke at home (OR = 2.29; 95% CI = 1.12–4.67). Alcohol consumption (OR = 2.55; 95% CI = 1.26–5.17), family history of psoriasis (OR = 33.96; 95% CI = 14.14–81.57) and change in work conditions (OR = 8.34; 95% CI = 1.86–37.43) are also risk factors for psoriasis. Separate analyses for men and women showed that the risk of developing psoriasis was stronger in men with a family history of psoriasis (OR = 30.39; 95% CI = 6.72–137.42) than in women (OR = 16.99; 95% CI = 7.21–40.07). The effect of environmental tobacco smoke at home was found only in women (OR = 2.44; 95% CI = 1.26–4.73). Future well-designed epidemiological studies need to be performed in order to determine whether lifestyle factors and stress could be risk factors triggering or aggravating psoriasis.     

Supercritical fluid drying of carbohydrates: selection of suitable excipients and process conditions.

The processibility of 15 carbohydrates, more or less commonly used, was investigated as excipients in supercritical fluid drying. The focus was on the ability to produce amorphous powder, the stability of the powders towards crystallisation, and the residual water and ethanol content. The aqueous solutions were sprayed into a pressurised carbon dioxide-ethanol mixture flowing cocurrently through a coaxial two-fluid nozzle. The powder characteristics appeared to be influenced by the supersaturation level reached during the SCF-drying process and by the properties of the sugar species, such as water solubility and glass transition temperature, or the solution viscosities. The stability and the residual solvent content of a selected set of sugars and some mixtures were further analysed. The stability of amorphous powders was investigated at 4 degrees C, room temperature, 40 and 50 degrees C. Lactose, maltose, trehalose, raffinose, cyclodextrin, low-molecular-weight dextran and inulin could form free-flowing powders that remained amorphous during the 3-month stability study. Sucrose had to be mixed with other sugars to form a stable amorphous powder. Ethanol could be entrapped in supercritical fluid dried low-molecular-weight sugars, whereas polysaccharide powders were free of ethanol. Measures to prevent or overcome the presence of ethanol are discussed.     

Croatian population data for the C677T polymorphism in methylenetetrahydrofolate reductase: frequencies in healthy and atherosclerotic study groups

BACKGROUND: The aim of this study was to investigate the frequency of C677T methylenetetrahydrofolate reductase (MTHFR) mutation in healthy Croatian volunteers and in patients with atherosclerosis. METHODS: The C677T MTHFR gene mutation was determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) in 640 subjects, residents of the Zagreb city or Zagreb surroundings. Control group (n=298) was healthy blood donors. Patients (n=342) were divided into two groups of those with coronary heart disease, CAD (n=247) and those with >60% carotid stenosis, CS (n=95). RESULTS: CC genotype was recorded in 45% of healthy volunteers and 46% of patients (46.3% with CS and 46.2% with CAD). TC genotype was found in 49% of healthy volunteers and 45% of patients (46.3% with CS and 44.9% with CAD). There was no significant difference (p>0.05) from the control group in the genotype or allele frequency either for the overall group of patients with atherosclerosis or for the patient subgroups. CONCLUSION: The preliminary study of MTHFR polymorphism in control subjects and cardiovascular disease/carotid stenosis patients revealed that in Croats there was a low frequency of TT genotype (6% in controls vs. 9% in patients) and T allele (31% for cases and controls). Additionally, our results did not show significantly higher frequency of MTHFR mutation in CAD and CS studied groups.     

cAMP levels in lymphocytes and CD4+ regulatory T‐cell functions are affected by dopamine receptor gene polymorphisms

The neurotransmitter dopamine (DA) has prominent effects in the immune system and between the immune cells, CD4⁺ regulatory T (Treg) lymphocytes, a specialized T‐cell subset crucial for the control of immune homeostasis, are especially sensitive to DA. Dopaminergic receptors (DR) are grouped into two families according to their pharmacological profile and main second messenger coupling: the D₁‐like (D₁ and D₅), which activate adenylate cyclase, and the D₂‐like (D₂, D₃ and D₄), which inhibit adenylate cyclase and exist in several variants that have been associated to clinical conditions such as schizophrenia, bipolar disorder, substance abuse and addiction. We aimed to examine, in venous blood samples from healthy volunteers, the relationship between the arbitrary DR score and DR functional responses in human lymphocytes. All the samples were genotyped for selected DR gene variants (DRD1: rs4532 and rs686; DRD2: rs1800497 and rs6277; DRD3: rs6280; DRD4: rs747302 and seven 48‐base pair variable number tandem repeat (VNTR)) and a DR score was attributed to each participant. We have also tested whether DR gene polymorphisms might affect Treg cell ability to suppress effector T‐cell function. To our knowledge, this is the first study showing a correlation between DR gene variants and human T lymphocyte function. The main results are that both D₁‐like and D₂‐like DR are functionally active in human lymphocytes, although the D₁‐like DR stimulation results in stronger effects in comparison to the D₂‐like DR stimulation. In addition, it seems that the DR genetic profile may affect the ability of lymphocytes to respond to dopaminergic agents. More investigations are needed about the possible clinical relevance of such findings.     

Subsequent stress increases gene expression of catecholamine synthetic enzymes in cardiac ventricles of chronic-stressed rats

Since previous experience of stressful situation profoundly affects response to a subsequent novel stressor, we examined changes in gene expression and protein levels of catecholamine biosynthetic enzymes in cardiac ventricles after exposure of chronic psychosocially isolated adult Wistar male rats to short-term immobilization stress. Chronic social isolation did not affect gene expression of tyrosine hydroxylase (TH) in either right or left ventricle. Subsequent immobilization of these animals produced an elevation of TH mRNA level in right and left ventricles. The levels of dopamine-β-hydroxylase (DBH) mRNA were detectable only after immobilization both in right and left ventricles of control and chronically isolated rats. Chronic isolation stress increased phenylethanolamine N-methyltransferase (PNMT) mRNA levels in the right ventricle. Immobilization led to an elevated PNMT mRNA level in right and left ventricles of both control and chronically stressed animals. Protein levels of TH, DBH, and PNMT in right and left ventricles of socially isolated rats were increased after subsequent immobilization. Taking into consideration the role of cardiac catecholamines in physiological and pathophysiological processes, it could be hypothesized that increased catecholamine synthesis in the ventricles after novel immobilization stress could point to the susceptibility of the heart to subsequent stress.     

Overcoming instability and low solubility of new cytostatic compounds: a comparison of two approaches

The pharmaceutical use of some 3-hydroxyquinolinone derivatives with high cytotoxic and cytostatic activities (under in vitro conditions) as well as potential immunosuppressive properties is seriously limited by their low solubility in water accompanied by instability in oxidative environment, like physiological fluids. In an attempt to improve the bioavailability and the stability of four of these derivatives, we propose here two different approaches: complexation with β-cyclodextrin derivatives and incorporation of these substances inside antioxidant micelles. The comparison of the two different methods is the focus of this work, as well as the investigation of some physicochemical properties of the micellar aqueous dispersions. Antioxidant micellar dispersions appear to be suitable for increasing the apparent solubility and stability for all the compounds studied, most probably because of the antioxidant activity of the specific surfactant used, combined with the low amount of water present in the center of the micelles. On this regard, (1)H NMR and UV-vis spectroscopy result as efficient tools to verify that the drug molecules are indeed placed in the core of the micelles. Moreover, freeze-drying provides a very easy and powerful technique to obtain solid formulations starting from micellar dispersions. On the contrary, cyclodextrins could potentially be used as solubilizing agents, but the drawback connected to degradation in aqueous media could not be overcome with this type of solubilizer.     

Cathepsin X cleavage of the beta2 integrin regulates talin-binding and LFA-1 affinity in T cells

T cell migration, essential for immune surveillance and response, is mediated by the integrin LFA-1. CatX, a cysteine carboxypeptidase, is involved in the regulation of T cell migration by interaction with LFA-1. We show that sequential cleavage of C-terminal amino acids from the β(2) cytoplasmic tail of LFA-1, by CatX, enhances binding of the adaptor protein talin to LFA-1 and triggers formation of the latter's high-affinity form. As shown by SPR analysis of peptides constituting the truncated β(2) tail, the cleavage of three C-terminal amino acids by CatX resulted in a 1.6-fold increase of talin binding. Removal of one more amino acid resulted in a 2.5-fold increase over the intact tail. CatX cleavage increased talin-binding affinity to the MD but not the MP talin-binding site on the β(2) tail. This was shown by molecular modeling of the β(2) tail/talin F3 complex to be a result of conformational changes affecting primarily the distal-binding site. Analysis of LFA-1 by conformation-specific mAb showed that CatX modulates LFA-1 affinity, promoting formation of high-affinity from intermediate-affinity LFA-1 but not the initial activation of LFA-1 from a bent to extended form. CatX post-translational modifications may thus represent a mechanism of LFA-1 fine-tuning that enables the trafficking of T cells.     

Botulinum toxin efficacy in the treatment of patients with spasmodic dysphonia

BACKGROUND/AIM: Spasmodic dysphonia (DS) is a disabling speech disturbance appearing as the consequence of dystonic vocal folds contraction. Its intermittent appearance in the laryngeal muscles causes vocal function discontinuation. The quality of life of these patients is significantly disturbed. Surgical and a medical therapy appear to be inadequate and unsuccessful ones of no steady improvement. It is the botulinum toxin therapy that proved to be highly efficacious one, with the established improvement in 80-100% of patients. The aim of our study was to evaluate the efficacy of botulinum toxin therapy in patients with SD and to show our preliminary results. METHODS: The study included 10 patients with adductor spasmodic dysphonia. After diagnostic procedures, botulinum toxin was applied either in one or both vocal folds, in doses of 12-16 units each. In our study we applied indirect technique originally developed by Hocevar and Pirtosek. Perceptive voice and speech analysis was performed prior to and after the instillation of botuline toxin as per structured Scale of pathological characteristics of voice and speech appearing in the spasmodic dysphonia. RESULTS: The majority of our patients experienced both subjective improvement and the improvement in the terms of the quality of life, Voice Henolicap Index--(VHI) that was rated as rather significant one (t = 3.562; p = 0.006). CONCLUSION: Regardless unquestionable improvement of definite phonation, further function restitution requires individual vocal therapy and psychotherapy. Vocal therapy includes structural vocal techniques which reduce degree of vocal tension and rapid changes in the power and the height of voice. Further investigations are necessary for the scope of the definition of a standardized therapeutically procedure for spasmodic dysphonia treatment which comprises multidisciplinary approach in diagnosis, therapy and treatment efficacy evaluation.