Effect of thymol and carvacrol on nutrient digestibility in rams fed high or low concentrate diets

Published data on the effects of essential oils (EO) on in vivo nutrient digestibility in sheep are contradictory. In 2 experiments, the effect of thymol and carvacrol on nutrient digestibility was studied in sheep fed with high (70%) or low (52%) concentrate diets, using incomplete Latin Square designs. The essential oils were mixed with the concentrate portion of the diet at the rate of 0.0, 0.3, or 0.6 g per kg dry matter (DM) diet. Supplementation of thymol had no significant effect on digestibility of dry matter (DM), organic matter (OM), crude protein (CP) and acid detergent fiber (ADF). The main effect of thymol on neutral detergent fiber (NDF) and ether extract (EE) digestibility and on nitrogen balance (NB) was significant (P<0.05), but within each level of dietary concentrate no significant differences were observed for these measurements. Overall, ruminal ammonia concentration was higher (P<0.05) in both HCD and LCD lambs receiving 0.3 mg thymol per kg diet. Supplementation of carvacrol had no significant effect on nutrient digestibility. The main effect of carvacrol on ruminal ammonia levels and NB was significant, but within each level of dietary concentrate no significant differences were observed in ammonia levels and NB. Inclusion of 0.3 g/kg diet DM of carvacrol or thyme was more effective than 0.6 g/kg diet DM in terms of NB but neither dose affected nutrient digestibility. Future research should determine the long-term effects of essential oils on digestibility and performance in sheep, before recommendation can be made for their use under practical husbandry conditions.Key Words: Carvacrol, Digestibility, Essential oils, Sheep, Thymol     

Red cell membrane stiffness in iron deficiency

The purpose of this study was to characterize red blood cell (RBC) deformability by iron deficiency. We measured RBC deformability to ektacytometry, a laser diffraction method for determining the elongation of suspended red cells subjected to shear stress. Isotonic deformability of RBC from iron-deficient human subjects was consistently and significantly lower than that of normal controls. In groups of rats with severe and moderate dietary iron deficiency, RBC deformability was also reduced in proportion to the severity of iron deficiency. At any given shear stress value, deformability of resealed RBC ghosts from both iron-deficient humans and rats was lower than that of control ghosts. However, increase of applied shear stress resulted in progressive increase in ghost deformation, indicating that ghost deformability was primarily limited by membrane stiffness rather than by reduced surface area-to-volume ratio. This was consistent with the finding that iron-deficient cells had a normal membrane surface area. In addition, the reduced mean corpuscular hemoglobin concentration (MCHC) and buoyant density of the iron-deficient rat cells indicated that a high hemoglobin concentration was not responsible for impaired whole cell deformability. Biochemical studies of rat RBC showed increased membrane lipid and protein crosslinking and reduced intracellular cation content, findings that are consistent with in vivo peroxidative damage. RBC from iron-deficient rats incubated in vitro with hydrogen peroxide showed increased generation of malonyldialdehyde, an end-product of lipid peroxidation, compared to control RBC. Taken together, these findings suggest that peroxidation could contribute in part to increased membrane stiffness in iron- deficient RBC. This reduced membrane deformability may in turn contribute to impaired red cell survival in iron deficiency.     

Molecular diagnosis of X-linked chronic granulomatous disease in Iran

Chronic granulomatous disease (CGD) is an inherited disorder of pathogen killing by phagocytic leukocytes caused by mutations in NADPH oxidase subunits. Patients with CGD have life-threatening bacterial and fungal infections. Children’s Medical Center at Tehran University is the referral center for immunodeficiency in Iran. During 2 years of study, 11 non-consanguineous families with clinically diagnosed CGD were referred to this center. In functional assays performed on neutrophils from affected children and their mothers; no activity or strongly decreased oxidase activity was detected in the patients’ cells. In oxidase tests that scored this activity on a per-cell basis, a mosaic pattern was detected in the neutrophils from all 11 mothers. Western blot analysis revealed an X91° phenotype in all patients. Mutation screening in the CYBB gene encoding gp91^phox by SSCP analysis followed by sequencing showed nine different mutations, including two novel mutations. The present survey is the first study aimed to analyze the clinical features and the molecular diagnosis of X-CGD in Iranian patients.     

The relative importance of thrombin inhibition and factor Xa inhibition to the antithrombotic effects of heparin

The relative importance of antithrombin and anti-factor Xa activities of heparin fractions required to achieve optimal antithrombotic effects is unknown. To study this, we measured the effects of standard heparin, an octasaccharide heparin fraction (anti-factor Xa activity only), and dermatan sulfate (antithrombin activity only) on the prevention of thrombosis and related this to their anticoagulant effects in vivo in rabbits. Thrombosis was measured as the incorporation of 125I- fibrinogen into tissue thromboplastin-induced thrombi using a Wessler- type model. Ex vivo changes in thrombin clotting time (TCT) were used as an index of antithrombin activity, and a chromogenic anti-factor Xa assay was used to measure anti-factor Xa activity. In addition, the ability of the three sulfated polysaccharides to simultaneously inhibit the generation of thrombin activity and to enhance the inactivation of the factor Xa added to initiate thrombin generation in plasma was determined. Standard heparin, in a dose of 10 anti-factor Xa U/kg, inhibited thrombus formation by 90%, prolonged the TCT by two seconds, and resulted in an anti-factor Xa level of 0.32 U/mL. The octasaccharide heparin fraction, in a dose of 10 anti-factor Xa U/kg, inhibited thrombus formation by 41%, had no effect on the TCT, and resulted in an anti-factor Xa level of 0.28 U/mL. Higher doses of the octasaccharide resulted in a further increase in the anti-factor Xa levels but had no further effect on thrombus formation. Dermatan sulfate, in a dose of 500 micrograms/kg, inhibited thrombus formation by 95%, but had no affect on the TCT. These results indicate that the antithrombotic effect achieved by inhibiting factor Xa is limited and that better antithrombotic effects are achieved by heparin or heparin- like substances capable of influencing the inactivation and/or the generation of thrombin.     

Fear Assessment in Inflammatory Rheumatic diseases (FAIR) questionnaire: a cross-cultural adaptation and validation to the Turkish language

In chronic inflammatory rheumatic diseases (CIRD), it is important to understand patients’ fears towards their disease in order to improve patient-physician dialog, to raise the quality of care offered, and to optimize treatment adherence. In this study, we aimed to translate the Fear Assessment in Inflammatory Rheumatic diseases (FAIR) questionnaire into Turkish and evaluate its psychometric properties in patients with CIRD. One hundred fifteen patients filled the provided socio-demographic information form, FAIR-Tr questionnaire, Hospital Anxiety and Depression Scale (HADS), and Beck’s Hopelessness Scale (BHS). For the analysis of short-term reliability, 50 patients re-filled the FAIR-Tr questionnaire 1 week later. Internal consistency was evaluated with Cronbach’s α coefficient and test-retest reliability was evaluated with intraclass correlation coefficients (ICC). Construct validity analysis was investigated based on the correlation with HADS and BHS. All patients found FAIR-Tr easily understandable and acceptable. FAIR-Tr internal consistency (Cronbach’s α?=?0.93) and test-retest reliability (ICC?=?0.91) were excellent. Psychometric validation was proved upon observing high correlation with HADS (Anxiety, r?=?0.77; Depression, r?=?0.70) and moderate correlation with BHS (r?=?0.65). FAIR-Tr is a questionnaire that has excellent internal consistency and test-retest reliability. The successful correlation with HADS and BHS supported its psychometric validity in terms of evaluating the fear in CIRD cases. We think that FAIR-Tr is a specific scale that can help to evaluate the disease- and treatment-related fears of the Turkish patients with CIRD and may be useful in both routine practice and clinical studies.