Down regulation of the inverse relationship between parathyroid hormone and irisin in male vitamin D-sufficient HIV patients.

PURPOSE: Infection with the human immunodeficiency virus (HIV) predisposes to endocrine disorders, manifesting as a metabolic phenotype that affects the entire adipose-musculoskeletal unit (AMS). The present cross-sectional study aimed to investigate differences in irisin and adiponectin concentrations between people living with HIV and healthy controls, as well as to explore potential correlations between the levels of the aforementioned adipokines and markers of calcium homeostasis. METHODS: 46 HIV-infected individuals and 39 healthy controls (all men) were included in the study. Anthropometric data, adipokine levels, 25-hydroxyvitamin D [(25(OH)D)] and parathyroid hormone (PTH) concentrations were evaluated in the two groups. Correlations for the relationship between adiponectin, irisin, and PTH levels were examined. The results were adjusted for several confounders, including 25(OH)D levels, anthropometry, physical activity, bone mineral density, testosterone levels, and exposure to ultraviolet B radiation. RESULTS: Mean adiponectin concentrations were significantly lower in the HIV group compared to the control group: 5868 ± 3668 vs 9068 ± 4277 ng/mL, p = 0.011. The same was applicable to irisin concentrations: 8.31 ± 8.17 (HIV) vs 29.27 ± 27.23 (controls) ng/mL, p = 0.013. A statistically significant and negative correlation was observed between irisin and PTH in the control group (r = - 0.591; p = 0.033). In contrast, no significant correlation was observed between PTH and irisin in the HIV group (p = 0.898). CONCLUSION: Our results are the first to suggest a possible down regulation of the inverse relationship between PTH and irisin in HIV patients and to highlight that AMS dyshomeostasis could be involved in the development of skeletal and adipose HIV-related morbidities.

Study of frozen low density lipoprotein particles by using nanotechnology.

OBJECTIVES: To investigate the impact of freezing in -80°C on the structure of isolated low density lipoproteins (LDLs), using nanotechnology, such as Atomic Force Microscopy (AFM). DESIGN AND METHODS: Blood EDTA plasma was obtained from healthy subject and used immediately to isolate LDL by sequential ultracentrifugation at 10°C in 55,000 rpm for 3h, using a Beckmann XL-90 ultracentrifuge (75Ti rotor), in the presence of KBr in PBS. LDLs were then diluted with PBS until final concentrations of 5 and 15 mg LDL/dl. After initial observation, samples were frozen in -80°C for two weeks and observed again after thawing. Experiments were performed in triplicate on two smooth and clean substrates of different hydrophobicity, glass (HOPG) and Si (c-Si). Statistical significance was set at 0.05. RESULTS: Macroscopically, LDL particles formed aggregations in a dendroid layout. There were no differences between images taken from both substrates (HOPG and c-Si). Frozen samples presented significantly smaller LDL particles, than fresh ones. In specific, mean diameter of LDL particle in the fresh LDL sample was 19.77 nm, ranging from 13.34 to 28.76 nm. The frozen LDL sample had a mean diameter of 5.2 nm, ranging from 2.0 to 8.0 nm, which was significantly different from the unfrozen. CONCLUSIONS: Atomic Force Microscopy showed that freezing of LDL causes alterations in their size.

Impact of iron and folic acid supplementation on oxidative stress during pregnancy.

The aim of the study was to assess serum total antioxidant capacity (TAC) and the impact of supplements on oxidative stress (OS) during pregnancy. Fifty volunteer pregnant women (21-40 years old), in the 12 ± 2 weeks' and 38 ± 2 weeks' gestation of pregnancy (study group), and 25 non-pregnant healthy women (control group) were enrolled. All pregnant women were divided into two age groups (A1: < 35 years and A2: ≥ 35 years) and four groups according to supplementation (B1: iron, B2: folic acid, B3: both and B4: none). Antioxidant activity was assayed using the TAC kit (Cayman Chemical Co.). Level of statistical significance was p < 0.05. Serum TAC values in all pregnant women in the first trimester were significantly lower, as compared with those of the control group. Levels of TAC increased significantly in the third trimester of pregnancy, especially with folic acid or no supplementation. In conclusion, pregnancy is associated with OS, which is promoted by the administration of iron supplementation.

Effects of acute cigarette smoking on total blood count and markers of oxidative stress in active and passive smokers.

BACKGROUND: Free radicals, as a product of cigarette smoke, are considered to have deleterious effects causing oxidative stress. Acute active smoking seems to be followed by transient leukocytosis and delayed increase in neutrophil activation. The aim of the present study was to investigate the oxidative status of smokers and passive non-smokers, as well as the impact that acute cigarette smoking has on hematological parameters. METHODS: Thirty-two healthy volunteers, 16 active smokers (Group A) aged 20-23 years and 16 age-matched, non-smokers (Group B), 18 women and 14 men in total, participated voluntarily in the study. All subjects did not have any food, drink, or cigarette smoking for eight hours before the study. Each time, two active smokers and two non-smokers were exposed simultaneously for half an hour to the smoke of two cigarettes smoked consecutively by the smokers. Blood was drawn before and after the exposure to cigarette smoke. Whole blood was analyzed immediately for total blood count parameters and serum was stored in -70(◦)C until serum levels of malondialdehyde (MDA) and vitamin E (VitE), and total antioxidant capacity (TAC) were determined. RESULTS: No statistical significant difference was observed in the values of white blood cells and their subpopulations between the two groups and within the same group before and after exposure to cigarette smoke. In the group of smokers, granulocyte/lymphocyte ratio increased significantly, MDA levels showed significant elevation and protective VitE serum levels decreased significantly, whereas TAC was reduced, but not significantly, after the exposure. In the group of passive, non-smokers the results of the blood count parameters, MDA and VitE were similar to Group A, and there was a significant decrease in TAC, as well. Between the two groups, only hematocrit values and MDA levels differed significantly before the exposure to smoke, and no other significant difference was detected before or after the exposure, between active and passive smokers. CONCLUSIONS: Acute exposure to cigarette smoking affects hematological indexes and oxidative stress biomarkers negatively, in both active and passive smokers, with similar results. The outcome seems to be even worse in passive smokers regarding oxidative stress and antioxidant protection markers. Elimination of cigarette smoking could prevent the adverse effects for smokers, as well as for healthy non-smokers in their vicinity. Hippokratia 2015; 19 (4): 293-297.

Changes in antibiotic resistance of the most common Gram-negative bacteria isolated in intensive care units.

We studied the changes in antibiotic resistance of the most common Gram-negative bacteria isolated in the intensive care units at our hospital in 2000 and 2002. Bacterial identification was performed by use of the VITEK 60 analyser, and antibiotic susceptibilities were tested by the VITEK 60 analyser and the disk diffusion agar method. The bacteria isolated most frequently were Pseudomonas aeruginosa (132 strains in 2000 and 106 in 2002), Acinetobacter calcoaceticus (98 and 109 strains, respectively) and Klebsiella pneumoniae (53 and 83 strains, respectively). Acinetobacters presented the highest percentage resistance, with significant increases in resistance to imipenem (15% in 2000 and 67% in 2002) and piperacillin/tazobactam (41% and 72%, respectively). P. aeruginosa presented a significant increase in resistance to all antibiotics, except ceftazidime. A large increase was observed in the resistance of K. pneumoniae to amikacin (from 10% to 50%), ceftazidime (from 80% to 90%) and tobramycin (from 80% to 90%). No imipenem-resistant strains of K. pneumoniae were found.