Evaluation of plasma oxidative stress, with or without antioxidant supplementation, in superficial partial thickness burn patients: a pilot study

The Effects of Different Burn Dressings on Length of Telomere and Expression of Telomerase in Children With Thermal Burns

BACKGROUND

Burns are a common traumatic injury triggered by local tissue damage and a systemic response. In this study, we evaluated the effects of different burn dressings on telomere kinetics in children with thermal burn injury.

METHODS

Sixty children with thermal burn were included in this prospective study. The burn area of the patients included 20 to 50% total body surface area. Three different dressings (hydrofiber with silver [HFAg], poylactic membrane [PLM], and silver sulfadiazine [SSD]) and control groups were created. Telomere length in nucleated blood cells and telomerase expression in the skin tissue were evaluated in control and burn groups.

RESULTS

In the whole burn groups, telomere length in blood cells increased. The length of telomeres increased the most in the SSD group. The PLM group is the treatment that increases the number of squamous cell counts in the basal layer and telomerase expression in the skin. In HFAg and SSD groups, the expression of telomerase in the skin is decreased. In the HFAg group, the basal layer in the skin was also reduced in squamous cells.

CONCLUSION

In all burn groups, the telomere length of nucleated cells in the blood was higher than in the control group. SSD dressing along with autografting is the treatment method that maximizes telomere length in blood cells. The PLM has the most increased telomerase expression in the skin of burned patients. The PLM application increases the number of cells on both burned and normal skin.

Effects of different ascorbic acid doses on the mortality of critically ill patients: a meta-analysis

BACKGROUND

Low levels of ascorbic acid (AA) have been detected in critically ill patients in which AA supplementation leads to promising outcomes. However, the ability of AA to reduce mortality in critically ill patients remains controversial. In this study, we have performed a meta-analysis to evaluate the effects of AA dose on the mortality of critically ill adults.

METHODS

Electronic databases were searched for trials in which AA had been intravenously administered to critically ill patients regardless of the dose or the co-administration of antioxidant agents. The predefined primary outcome included all-cause mortality at final follow-up.

RESULTS

The included trials enrolled a total of 1210 patients. Intravenous (IV) AA doses of 3-10 g/d reduced the mortality of critically ill patients (OR 0.25; 95% CI (0.14-0.46); p < 0.001; I2 = 0.0%), while low (< 3 g/d) and high AA doses (≥ 10 g/d) had no effect (OR 1.44; 95% CI (0.79-2.61); p = 0.234; I2 = 0.0% versus OR 1.12; 95% CI (0.62-2.03); p = 0.700; I2 = 0.0%). AA was associated with a decreased duration of vasopressor support and mechanical ventilation, but did not influence fluid requirement or urine output during the first 24 h of admission. The number of patients suffering from acute kidney injury and the length of intensive care unit or hospital stays were also unaffected by the AA.

CONCLUSION

Intravenous AA reduces the duration of vasopressor support and mechanical ventilation; 3-10 g AA results in lower overall mortality rates. Given the limitations of the primary literature, further studies are required to fully clarify the effectiveness of AA during the management of critically ill patients.

Current Insights into the Biological Action of Squalene

Squalene is a triterpenic compound found in a large number of plants and other sources with a long tradition of research since it was first reported in 1926. Herein a systematic review of studies concerning squalene published in the last 8 years is presented. These studies have provided further support for its antioxidant, anti-inflammatory, and anti-atherosclerotic properties in vivo and in vitro. Moreover, an antineoplastic effect in nutrigenetic-type treatments, which depends on the failing metabolic pathway of tumors, has also been reported. The bioavailability of squalene in cell cultures, animal models, and in humans has been well established, and further progress has been made in regard to the intracellular transport of this lipophilic molecule. Squalene accumulates in the liver and decreases hepatic cholesterol and triglycerides, with these actions being exerted via a complex network of changes in gene expression at both transcriptional and post-transcriptional levels. Its presence in different biological fluids has also been studied. The combination of squalene with other bioactive compounds has been shown to enhance its pleiotropic properties and might lead to the formulation of functional foods and nutraceuticals to control oxidative stress and, therefore, numerous age-related diseases in human and veterinary medicine.

Plasma Oxidative Stress in Patients With Chronic Vascular Cutaneous Ulcers

Oxidative stress is hypothesized to be one of the main causes of the pathophysiologic alterations observed during impaired healing of wounds. In the present study, we aimed to measure systemic levels of free radicals in blood and anti-oxidant (AO) activity in the plasma of patients with chronic ulcers (venous stasis ulcers and arterial insufficiency ulcers) of lower extremities (CULEs). Oxidants and AO activity were measured in eighty-five consecutive patients with CVSUs of the lower extremities as they arrived randomly for routine visits to our ambulatory clinic. Values of oxidant and AO status in patients with CULEs were significantly different from normal. No significant differences in oxidant and AO values were found between patients with arterial ulcers or those with venous ulcers. A significant difference was found in AO values of diabetic patients with chronic venous ulcers compared with non-diabetic patients with chronic venous ulcers. No significant differences were observed when evaluating oxidant/AO values and smoking habits. Precise reasons why the association of diabetes and venous (but not arterial) ulcers was correlated with defective AO status in plasma are not known. Other data were also intriguing: diminished AO activity was observed in female patients, no significant differences in oxidant and values were found between patients with arterial ulcers or those with venous ulcers, no significant correlation was found between age and oxidant, as well as no significant differences were observed when evaluating oxidant/AO values and smoking habits.