Evaluation of the use of tacrolimus ointment for the prevention of hypertrophic scars in experimental model

Abstract BACKGROUND: Tacrolimus, for its activity on modulation of collagen production and fibroblast activity, may have a role in the prevention of hypertrophic scars. OBJECTIVES: Evaluate macroscopic, microscopic, metabolic, laboratory effects and side effects of the use of topical tacrolimus ointment, in different concentrations, in the prevention of hypertrophic scars. METHODS: Twenty-two rabbits were submitted to the excision of 2 fragments of 1 cm of each ear, 4 cm apart, down to cartilage. The left ear of the animals was standardized as control and Vaseline applied twice a day. The right ear received tacrolimus ointment, at concentrations of 0.1% on the upper wound and 0.03% on the lower wound, also applied twice a day. Macroscopic, microscopic, laboratory criteria and the animals' weight were evaluated after 30 days of the experiment. RESULTS: Wounds treated with tacrolimus, at concentrations of 0.1% and 0.03%, when compared to control, showed a lower average degree of thickening (p = 0.048 and p <0.001, respectively). The average of scar thickness and lymphocyte, neutrophil and eosinophil concentrations are lower in the treated wounds compared to the control (p <0.001, p=0.022, p=0.007, p=0.044, respectively). The mean concentration of lymphocytes is lower in wounds treated with a higher concentration of the drug (p=0.01). STUDY LIMITATIONS: experiment lasted only 30 days. CONCLUSIONS: Tacrolimus at the 2 concentrations evaluated reduced the severity of inflammatory changes and positively altered the macroscopic aspect of the scar in the short term. Its use was shown to be safe, with no evidence of systemic or local adverse effects.

Effects of trace elements on albumin and lipoprotein glycation in diabetic retinopathy

To test the effect of some trace elements, on protein and lipoprotein glycosylation and their impact on the severity of diabetic retinopathy. A case control study was conducted in 42 diabetic patients [14 without retinopathy [DC]; 14 with non-proliferative diabetic retinopathy [NPDR]; 14 with proliferative diabetic retinopathy [PDR]] at Ebin Al-Haitham Specialized Hospital, Baghdad, Iraq for Ocular Diseases from February to December 2008. In addition to 20 age and gender matched healthy controls [NC]. The glycation of albumin, alpha-, pre beta-, and beta-lipoproteins was measured by agarose gel electrophoresis. Serum levels of cadmium [Cd], selenium [Se], chromium [Cr], zinc [Zn], and copper [Cu] were analyzed by flameless atomic absorption spectrophotometer. There was significant elevation in the mean serum glycated beta-lipoprotein in DC [p<0.05] and a near significant increase [p=0.06] in the means of both glycated albumin and pre beta-lipoproteins among the PDR and NPDR groups. Moreover, a significant reductions in serum means of Cd [p<0.05] and Zn/Cu ratios [p<0.001] were recorded in all diabetic retinopaths as compared to DC. The Cd level rises with the increase in duration of diabetes [p<0.001] and hyperglycemia [p<0.025] whereas, the serum Cr values decreases with the progression of diabetes [p<0.025]. Both glycation and oxidative processes are involved in the development of diabetic retinopathy, and changes in the concentration of Cd, Se, Cr, Zn, and Cu have some impact on the disease progression

effects of acetaminophen on human serum albumin [HSA]

Thermal conformational changes in human serum albumin [HSA] in present with a 10 mM phosphate buffer, at pH=7 have been investigated via circular dichroism [CD] and UV spectroscopic methods. The results indicate that temperature in a range of 25oC to 55oC could induce a reversible conformational change in the structure of HSA. The HSA phase transition corresponds to the physiological and pathological conditions of the body, especially fever. The conformational change observed in HSA is accompanied by a mild conversion of its secondary structures. Acetaminophen is a papular pain killer, and HSA is used as a drug carrier. Hence, acetaminophen could it interact with HSA. The study of HSA - acetaminophen interaction reveals the effects of acetaminophen on HSA structure, preventing it's phase transition. HSA - acetaminophen interaction leads to the stabilization of HAS. This interaction is accompanied with 8 kJ/mol of free energy change. The structural changes within HSA due to it's interaction with acetaminophen could be considered as a drug side effect and it may affect the protein functions

Chloramphenicol clearance in typhoid fever: implications for therapy.

We prospectively studied the pharmacokinetics of intravenous Chloramphenicol succinate (CS) in children (age 6 months-14 years) with culture proven typhoid fever (n = 30) and non typhoidal illnesses (n = 10). CS was administered in three different dosage regimens (50, 75 and 100 mg/kg/d-q 6 hourly). Liver function tests were monitored. Plasma trough and peak chloramphenicol concentrations were measured by HPLC analysis after 42 hrs. The 50 mg/kg/day dosage schedule was terminated midway through the study, as blood levels were consistently low and two patients with typhoid relapsed, children with typhoid had significantly lower clearance of CS in comparison with those with non-typhoidal illness (0.29 +/- 0.1 versus 0.5 +/- 0.37 1/kg/hr, P 0.05). There was no significant difference between mean peak and trough concentrations of chloramphenicol on 100 mg/kg/day and 75 mg/kg/day in children with typhoid. However, two children on 100 mg/kg/day dosage developed trough concentrations greater than 20 mcg/ml. No correlation was found between CS clearance and serum bilirubin, SGPT (alanine transaminase) and alkaline phosphatase. Our data show altered clearance of CS in children with typhoid and suggests that 75 mg/kg/day may be a safer dose in children with hepatic dysfunction in typhoid.

Aglutininas antialbúminas / Antialbumin agglutinins

Se presentan dos casos de donantes cuyos sueros presentaron Aglutininas Antialbúminas con diferentes patrones de reactividad serológica. Ambos casos representan los primeros observados en el Banco de Sangre del Hospital Universitario de Caracas desde su fundación en 1956. Se hace una revisión de la evolución y progresión que en el conocimiento de estos anticuerpos se ha adquirido en el transcurso de los años y se señala la necesidad de conocerlos, a fin de evitar la confusión con anticuerpos específicos para los antígenos eritrocitarios de gran importancia en la terapia transfusional