Oxidative stress in androgenetic alopecia.

Rationale:Androgenetic alopecia is not considered a life threatening disease but can have serious impacts on the patient's psychosocial life. Genetic, hormonal, and environmental factors are considered responsible for the presence of androgenetic alopecia. Recent literature reports have proved the presence of inflammation and also of oxidative stress at the level of dermal papilla cells of patients with androgenetic alopecia Objective:We have considered of interest to measure the oxidative stress parameters in the blood of patients with androgenetic alopecia Methods and results:27 patients with androgenetic alopecia and 25 age-matched controls were enrolled in the study. Trolox Equivalent Antioxidant Capacity (TEAC), malondialdehyde (MDA) and total thiols levels were measured on plasma samples. Superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT) activities, and also non protein thiols levels together with TEAC activity were determined on erythrocytes samples No statistically significant changes were observed for TEAC erythrocytes, non-protein thiols, GPx and CAT activities. Significantly decreased (p<0.01) SOD activity was found in patients with androgenetic alopecia. For plasma samples decreased TEAC activity (p<0.001), increased MDA levels (p<0.001) and no change in total thiols concentration were found in patients when compared with the controls. Discussions:Decreased total antioxidant activity and increased MDA levels found in plasma samples of patients with androgenetic alopecia are indicators of oxidative stress presence in these patients. Significantly decreased SOD activity but no change in catalase, glutathione peroxidase, non protein thiols level and total antioxidant activity in erythrocytes are elements which suggest the presence of a compensatory mechanism for SOD dysfunction in red blood cells of patients with androgenetic alopecia. ABBREVIATIONS: AAG = androgenetic alopecia, MDA = malondialdehyde, SOD = superoxide dismutase, CAT = catalase, GPx = glutathione peroxidase, GSH = glutathione, GST = glutathione transferase, SH = thiols, TEAC = trolox equivalent antioxidant capacity, ABTS = 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid), CDNB = 1-chloro-2,4-dinitrobenzene.

Impact of chronic administration of anabolic androgenic steroids and taurine on blood pressure in rats.

Supraphysiological administration of anabolic androgenic steroids has been linked to increased blood pressure. The widely distributed amino acid taurine seems to be an effective depressor agent in drug-induced hypertension. The purpose of this study was to assess the impact of chronic high dose administration of nandrolone decanoate (DECA) and taurine on blood pressure in rats and to verify the potentially involved mechanisms. The study was conducted in 4 groups of 8 adult male Wistar rats, aged 14 weeks, treated for 12 weeks with: DECA (A group); vehicle (C group); taurine (T group), or with both drugs (AT group). Systolic blood pressure (SBP) was measured at the beginning of the study (SBP1), 2 (SBP2) and 3 months (SBP3) later. Plasma angiotensin-converting enzyme (ACE) activity and plasma end products of nitric oxide metabolism (NOx) were also determined. SBP3 and SBP2 were significantly increased compared to SBP1 only in the A group (P<0.002 for both). SBP2, SBP3 and ACE activity showed a statistically significant increase in the A vs C (P<0.005), andvs AT groups (P<0.05), while NOx was significantly decreased in the A and AT groups vs controls (P=0.01). ACE activity was strongly correlated with SBP3 in the A group (r=0.71, P=0.04). These findings suggest that oral supplementation of taurine may prevent the increase in SBP induced by DECA, an effect potentially mediated by angiotensin-converting enzyme.

Impact of chronic administration of anabolic androgenic steroids and taurine on blood pressure in rats

Supraphysiological administration of anabolic androgenic steroids has been linked to increased blood pressure. The widely distributed amino acid taurine seems to be an effective depressor agent in drug-induced hypertension. The purpose of this study was to assess the impact of chronic high dose administration of nandrolone decanoate (DECA) and taurine on blood pressure in rats and to verify the potentially involved mechanisms. The study was conducted in 4 groups of 8 adult male Wistar rats, aged 14 weeks, treated for 12 weeks with: DECA (A group); vehicle (C group); taurine (T group), or with both drugs (AT group). Systolic blood pressure (SBP) was measured at the beginning of the study (SBP1), 2 (SBP2) and 3 months (SBP3) later. Plasma angiotensin-converting enzyme (ACE) activity and plasma end products of nitric oxide metabolism (NOx) were also determined. SBP3 and SBP2 were significantly increased compared to SBP1 only in the A group (P<0.002 for both). SBP2, SBP3 and ACE activity showed a statistically significant increase in the A vs C (P<0.005), andvs AT groups (P<0.05), while NOx was significantly decreased in the A and AT groups vs controls (P=0.01). ACE activity was strongly correlated with SBP3 in the A group (r=0.71, P=0.04). These findings suggest that oral supplementation of taurine may prevent the increase in SBP induced by DECA, an effect potentially mediated by angiotensin-converting enzyme.

Clozapine and risperidone influence on cortisol and estradiol levels in male patients with schizophrenia.

Estrogens role in schizophrenia patients is a subject, which has gained an increased attention from the medical community. Estrogens have been shown to inhibit dopamine actions, improve neuronal regeneration, and overall, have a protective role in the pathology of schizophrenia. The adjunctive estrogen therapy for men is currently under debate. Antipsychotic medication is known to influence the hypothalamo-hypophyseal - gonadal axis by inducing variable degrees of hyperprolactinemia. Several studies have found that some of the atypical antipsychotics lower cortisol levels in patients and also in healthy controls. We have investigated the effects of clozapine and risperidone on estradiol levels in men with schizophrenia. We have also evaluated the levels of prolactin and cortisol, taking into account the possible influence of antipsychotic drugs on both these hormones. Both prolactin and cortisol also have the potential to regulate sexual hormones biosynthesis. Our study found decreased estradiol levels in men with schizophrenia treated with clozapine and risperidone, while prolactin levels were increased only in the risperidone treated group. Cortisol levels are not statistically significant different between groups.

Oxidative stress and alopecia areata.

Alopecia areata (AA) is an inflammatory and autoimmune disease presenting with non-scarring hair loss. The aethiopathogenesis of alopecia areata is unclear and many factors including autoimmunity, genetic predisposition, emotional and environmental stress are thought to play important roles in its development. Antioxidant/ oxidant balance perturbation is a common feature in autoimmune, emotional and environmental stress. Therefore, our paper discusses the implications of oxidative stress in alopecia areata.

Venous versus arterial iron administration in haemodialysis. Influence on erythrocytes antioxidant parameters.

Introduction Intravenous iron administration in patients treated by haemodialysis for end stage renal disease can exacerbate oxidative stress by increasing the level of free redox active iron. A way to reduce the impact of iron on oxidative stress in haemodialysis patients may be the administration of iron through arterial extracorporeal circuit. Objective The aim of our study was to compare the influence of iron route of administration (venous versus arterial extracorporeal circuit infusion) on antioxidant parameters in red blood cells of haemodialysis patients in order to clarify if arterial iron administration can have positive impacts related to iron induced oxidative stress. Method Twenty stable patients on regular haemodialysis treatment were selected for the study. They were investigated in a cross-over design at 3 mid-week HD sessions, one week apart, without iron [HD basal] and with either IV infusion of 100mg iron sucrose over the first 20 minutes of HD session, via venous line [HDvenous], or the same solution infused on the arterial extracorporeal circulation [HDarterial]. Blood samples were drawn at 0 min, 40 min and 270 min. Erythrocytes superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px) activity, non-protein thiol levels and total antioxidant capacity (TEAC) were analysed. Conclusion Haemodialysis significantly decreases the total antioxidant activity in erythrocytes. Iron supplementation, through venous or arterial extracorporeal route has no impact on the total antioxidant activity in red blood cells. Venous iron administration increases GPx activity in erythrocytes suggesting increased lipid peroxidation compared with arterial extracorporeal administration.

Salivary changes related to systemic diseases in the edentulous patients.

INTRODUCTION: The relatively frequent systemic comorbidities of geriatric patients can be linked to salivary changes, which may induce oral alteration and discomfort with the removable prosthesis. The aim of the study was to evaluate the salivary parameters in completely edentulous patients treated by removable prosthesis, in relation to their general health status. MATERIAL AND METHOD: A cross-sectional study was performed on 30 completely edentulous patients, 53% male and 47% female, aged between 53 and 84. The evaluation of the salivary parameters (oral hydration index, pH and salivary flow, viscosity and saliva buffer capacity) was performed with the Saliva Check Buffer kit (GC Corporation). RESULTS: The salivary changes encountered were the following: low hydration level (63%), high saliva viscosity (57%), below-average pH (27%), reduced salivary flow (77%) and low saliva buffer capacity (80%). A reduced salivary flow and saliva buffer capacity was found in women. A lower buffer capacity of the saliva was found in patients with respiratory and gastro-intestinal disease. CONCLUSIONS: The alterations of the salivary flow are relatively frequent in geriatric patients, removable denture wearers, with compromised systemic status. These changes may be a risk factor for denture stomatitis and oral candidiasis, with a negative effect on the patient's comfort and quality of life.

Lidar returns from multiply scattering media in multiple-field-of-view and CCD lidars with polarization devices: comparison of semi-analytical solution and Monte Carlo data.

Quite recently, a semi-analytical approach to the sounding of multiply scattering media (clouds, seawaters) using multiple-field-of-view and CCD lidars with polarization devices was developed. The angular distributions of polarized components of the lidar returns from multiply scattering media computed on the basis of this theory using the small-angle approximation are presented and discussed. The semi-analytical nature of the solution makes the computation procedure faster. The obtained data are compared with results provided by the most advanced Monte Carlo algorithms for simulation of modern lidar performance. The good agreement between data provided by the semi-analytical approach and Monte Carlo computations assures one that these approaches can serve as a reliable theoretical base for interpretation and inversion of cloud lidar sounding data obtained with polarized lidars, including polarized multiple-field-of-view and CCD lidars.

Demodulation techniques for the amplitude modulated laser imager.

A new technique has been found that uses in-phase and quadrature phase (I/Q) demodulation to optimize the images produced with an amplitude-modulated laser imaging system. An I/Q demodulator was used to collect the I/Q components of the received modulation envelope. It was discovered that by adjusting the local oscillator phase and the modulation frequency, the backscatter and target signals can be analyzed separately via the I/Q components. This new approach enhances image contrast beyond what was achieved with a previous design that processed only the composite magnitude information.

Simple model of the optical characteristics of bubbles and sediments in seawater of the surf zone.

The development of a simple model of the seawater inherent optical properties (IOPs) associated with bubbles and sediments would represent a great advance in surf zone optics. We present one solution for this problem using a combination of geometrical optics and Fraunhofer diffraction. An analytic model of the IOPs of bubbles and sediments (the extinction and absorption coefficients, and phase function) is developed in terms of the moments of the particle size distribution and the complex refractive index of particles.

Amplitude-modulated laser imager.

Laser systems have been developed to image underwater objects. However, the performance of these systems can be severely degraded in turbid water. We have developed a technique using modulated light to improve underwater detection and imaging. A program, Modulated Vision System (MVS), which is based on a new theoretical approach, has been developed to predict modulated laser imaging performance. Experiments have been conducted in a controlled laboratory environment to test the accuracy of the theory as a function of system and environmental parameters. Results show a strong correlation between experiment and theory and indicate that the MVS program can be used to predict future system performance.