No abstract

We analyzed the effect of diosgenin, administered with atorvastatin or ezetimibe, on the fate of 3H(G)-taurocholic acid or 26-14C-cholesterol in hypercholesterolemic rats. Male Wistar rats received a hypercholesterolemic diet (HD), HD + atorvastatin (HD+ATV), HD + ezetimibe (HD+EZT), HD + diosgenin (HD+DG), HD+ATV+EZT, or HD+ATV+DG for 40 days. We also included a control normal group (ND). The labelled compounds were administered on day 30. The animals were placed in metabolic cages for daily feces collection. At day 40 the rats were sacrificed. Lipid extracts from blood, liver, spinal cord, testicles, kidneys, epididymis, intestine, and feces were analyzed for radioactivity. Cholesterol activity was the highest in the liver in HD rats. DG diminished one half of this activity in HD+DG and HD+ATV+DG groups in comparison with the HD group. HD+ATV rats showed four to almost ten-fold cholesterol activity in the spinal cord compared with the ND or HD rats. Fecal elimination of neutral steroids was approximately two-fold higher in the HD+DG and HD+ATV+DG groups. Taurocholic acid activity was four to ten-fold higher in HD+DG intestine as compared to the other experimental groups. Taurocholic activity in the liver of HD and HD+DG groups was two and a half higher than in ND. Our results show that the combination of DG and ATV induced the highest cholesterol reduction in the liver and other tissues.

Suicides and suicidal behavior are major causes of mortality and morbidity in public health and are a global problem. Various authors have proposed changes in lipid metabolism (total cholesterol decrease) as a possible biological marker for suicidal behavior. The objective of this study was to review the studies that have demonstrated a relationship between serum cholesterol levels and suicidal behavior and to describe the possible pathophysiological mechanisms that associate changes in cholesterol concentration and suicidal behavior. Relevant literature related to serum cholesterol levels and suicidal behavior was identified through various database searches. The data from the existing literature present the findings that relate low cholesterol levels and possible pathophysiological mechanisms (neuroinflammation, serotonergic neurotransmission), genes related to cholesterol synthesis, pharmacological treatments that alter lipid metabolism and the possible participation in suicidal behavior. Nevertheless, future research is required to describe how serum cholesterol affects cholesterol metabolism in the CNS to establish and understand the role of cholesterol in suicidal behavior.

Hypoxemia is defined as the decrease in arterial partial pressure of oxygen (PaO2) below 80 mmHg. One of the ways to alleviate this condition is through oxygen therapy, which consists of administering oxygen at a concentration higher than atmospheric. This therapy is indicated in various pathologies and is aimed to treat hypoxemia and reduce the patient's myocardial demand and respiratory effort. Classically, this treatment has been carried out using low-flow systems, in which the inspiratory fraction of oxygen (FiO2) cannot be regulated. However, an increase in the use of high-flow oxygen therapy (HFO) has been observed in recent years. These systems allow for greater patient comfort as well as more precise regulation of the FiO2. The purpose of this article is to review respiratory physiology to understand respiratory failure from a clinical and pathophysiological point of view. Likewise, the different oxygen therapy systems most widely used are discussed, as well as their indications for acute and chronic pathologies, both in the pediatric and adult populations.

Q fever is a worldwide zoonosis caused by Coxiella burnetii. Looking to the duration of the disease, Q fever may be divided into acute and chronic forms. In humans, acute C. burnetii is often asymptomatic or mistaken for an influenza-like illness or atypical pneumonia. On the other hand, chronic Q fever is characterized by a spontaneous evolution lasting for > 6 months and a high level of IgG antibodies titre, generally determined by the indirect fluorescence antibody (IFA). However, other clinical manifestations may be observed, including hepatic, neurologic, dermatologic, and cardiac disturbs. Teha last one includes pericarditis, which has been observed in 1% of patients affected by C. burnetii infection. However, this incidence is probably underestimated. In fact, over 80% of acute as well as recurrent pericarditis remains aetiologically unexplained.We describe a case of a 36-year-old man reporting progressive onset of dyspnea, chest pain and dysthermia sensation. Ambulatory treatment was unsatisfactory developing a severe respiratory failure recquiring his admission in the Critical Care Department. Blood test showed discrete leukocytosis with left deviation and increased reactive protein C levels. Thoracic computed tomography (CT) showed a 22mm pericardial effusion with a bilateral pleural effusion more marked in the left lung area. Microbiological as well as serological studies showed positive IgM titers to C. Burnetii. Doxycycline treatment was initiated with postive results.

Statins are the cornerstone of therapy for individuals with hyperlipidemia. The aim of this study was to analyze the undesirable effects of mild, moderate and high doses of rosuvastatin in CD-1 male mice who received a cholesterol-rich diet, focusing on the morphological and functional changes on hepatocyte mitochondria. In a mouse model we studied the combined administration of a cholesterol-rich diet along with mild and moderate doses of rosuvastatin (1, 2.5 or 5 mg/kg/day) during several days. After the animals were sacrificed, liver mitochondria were isolated for microscopic studies and to analyze the respiratory function. The respiratory control (state-3/state-4) was evaluated in mice who received high doses of rosuvastatin. Rosuvastatin doses higher than 20 mg/kg/day induced premature death in mice with a hypercholesterolemic diet, but not in mice with a cholesterol-free diet. Doses from 2.5 to 5 mg/kg/day also induced morphological and functional alterations in mitochondria but these hypercholesterolemic animals survived longer. Giving 1 mg/kg/day, which is close to the maximal therapeutic dose for humans, did not affect mitochondrial architecture or respiratory function after two months of treatment. We analyzed the effect of rosuvastatin on hepatic tissue because it is where statins are mainly accumulated and it is the main site of endogenous cholesterol synthesis. Our results contribute to understand the side effects of rosuvastatin in hypercholesterolemic mice, effects that could also affect humans who are intolerant to statins.

ABSTRACT. Fabry disease (FD) is an inherited X-linked lysosomal disease that causes renal failure in a high percentage of affected individuals. The eNOS gene encodes for endothelial nitric oxide synthase, which plays an important role in glomerular hemodynamics. This gene has two main polymorphisms (Glu298Asp and 4b/a) that have been studied in the context of many different diseases, including those involving cardiovascular and renal alterations. Considering the lack of information regarding eNOS variants and FD, we investigated whether there were associations between eNOS genetic variants and renal function parameters in Mexican patients with FD and renal impairment. In total, 15 FD patients with renal alterations were included in the present study, and associations between eNOS polymorphisms and renal function parameters (urea, creatinine, and GFR) were evaluated. The Asp298 and 4a alleles of the eNOS gene were found to be significantly associated with increased levels of urea and creatinine, and a decreased glomerular filtration rate in FD patients, and this association behaved in a co-dominant fashion. Our results coincide with previous reports showing an association between these polymorphisms and kidney disease, and along with other studies regarding their role in the nitric oxide pathway, suggest that these variants affect the severity of nephropathy in patients with FD.

From studies using different experimental techniques employed to determine the presence of aggregates e.g. isothermal titration calorimetry, surface tension, electrical conductivity, UV–Vis spectrophotometry, dynamic and static light scattering, it is clearly demonstrated that the compound [Cu(4, 4′-dimethyl-2, 2′-bipyridine)(acetylacetonato)H2O]NO3 (Casiopeína III-ia), promising member of a family of new generation compounds for cancer treatment, is able to auto associate in aqueous media. Physicochemical properties associated with the formation of the aggregates were determined in pure water and in phosphate buffer media in order to simulate physiological conditions. From isothermal titration calorimetry and electrical conductivity measurements we calculated the dissociation constant of the aggregates, K D. For pure water the values obtained in both techniques are 2.73 × 10−4 and 5.93 × 10−4 M respectively while for the buffer media we obtained 4.61 × 10−4 and 1.57 × 10−3 M. The enthalpy of dissociation, ∆H D, calculated from the calorimetric data shows that the presence of the phosphate ions has an energetic effect on the aggregate stability since in pure water a value of 18.79 kJ mol−1 was obtained in comparison with the buffer media where a value 4 times bigger was found (70.48 kJ mol−1). With the data collected from these techniques the number of monomers calculated which participate in the formation of the aggregates is around two. From our surface tension, electrical conductivity and UV–Vis spectrophotometry measurements the critical aggregate concentration, cac, was determined. For each technique specific concentration ranges were obtained but we can summarize that the cac in pure water is between 3 and 3.5 mM and for the buffer media is between 3.5 and 4 mM. Dynamic light scattering measurements provide us with the hydrodynamic diameter of the aggregates and from static light scattering measurements we determined the molecular weight of the Casiopeína III-ia aggregates to be of 1000.015 g mol−1 which is two times the molecular weight of the Casiopeína III-ia molecule. This value is in agreement with the number of monomers which participate in the formation of the aggregates obtained from isothermal titration calorimetry and electrical conductivity data analysis.