Complex interactions between nicotine and resveratrol in the Drosophila melanogaster wing spot test.

Nicotine (NIC) and resveratrol (RES) are chemicals in tobacco and wine, respectively, that are widely consumed concurrently worldwide. NIC is an alkaloid known to be toxic, addictive and to produce oxidative stress, while RES is thought of as an antioxidant with putative health benefits. Oxidative stress can induce genotoxic damage, yet few studies have examined whether NIC is genotoxic in vivo. In vitro studies have shown that RES can ameliorate deleterious effects of NIC. However, RES has been reported to have both antioxidant and pro-oxidant effects, and an in vivo study reported that 0.011 mM RES was genotoxic. We used the Drosophila melanogaster wing spot test to determine whether NIC and RES, first individually and then in combination, were genotoxic and/or altered the cell division. We hypothesized that RES would modulate NIC's effects. NIC was genotoxic in the standard (ST) cross in a concentration-independent manner, but not genotoxic in the high bioactivation (HB) cross. RES was not genotoxic in either the ST or HB cross at the concentrations tested. We discovered a complex interaction between NIC and RES. Depending on concentration, RES was protective of NIC's genotoxic damage, RES had no interaction with NIC, or RES had an additive or synergistic effect, increasing NIC's genotoxic damage. Most NIC, RES, and NIC/RES combinations tested altered the cell division in the ST and HB crosses. Because we used the ST and HB crosses, we demonstrated that genotoxicity and cell division alterations were modulated by the xenobiotic metabolism. These results provide evidence of NIC's genotoxicity in vivo at specific concentrations. Moreover, NIC's genotoxicity can be modulated by its interaction with RES in a complex manner, in which their interaction can lead to either increasing NIC's damage or protecting against it.

Association between adiposity levels and cognitive impairment in the Chilean older adult population.

Although both obesity and ageing are risk factors for cognitive impairment, there is no evidence in Chile on how obesity levels are associated with cognitive function. Therefore, the aim of the present study was to investigate the association between adiposity levels and cognitive impairment in older Chilean adults. This cross-sectional study includes 1384 participants, over 60 years of age, from the Chilean National Health Survey 2009-2010. Cognitive impairment was evaluated using the Mini-Mental State Examination. BMI and waist circumference (WC) were used as measures of adiposity. Compared with people with a normal BMI, the odds of cognitive impairment were higher in participants who were underweight (OR 4·44; 95 % CI 2·43, 6·45; P < 0·0001), overweight (OR 1·86; 95 % CI 1·06, 2·66; P = 0·031) and obese (OR 2·26; 95 % CI 1·31, 3·21; P = 0·003). The associations were robust after adjustment for confounding variables. Similar results were observed for WC. Low and high levels of adiposity are associated with an increased likelihood of cognitive impairment in older adults in Chile.

Occurrence of antibiotics and bacterial resistance in wastewater and sea water from the Antarctic.

The potential presence of introduced antibiotics in the aquatic environment is a hot topic of concern, particularly in the Antarctic, a highly vulnerable area protected under the Madrid protocol. The increasing presence of human population, especially during summer, might led to the appearance of pharmaceuticals in wastewater. The previous discovery of Escherichia coli strains resistant to antibiotics in sea water and wastewater collected in King George Island motivated our investigation on antibiotics occurrence in these samples. The application of a multi-residue LCMS/MS method for 20 antibiotics, revealed the presence of 8 compounds in treated wastewater, mainly the quinolones ciprofloxacin and norfloxacin (92% and 54% of the samples analyzed, average concentrations 0.89 µg/L and 0.75 µg/L, respectively) and the macrolides azithromycin and clarithromycin (15% positive samples, and average concentrations near 0.4 µg/L), and erythromycin (38% positive samples, average concentration 0.003 µg/L). Metronidazole and clindamycin were found in one sample, at 0.17 and 0.1 µg/L, respectively; and trimethoprim in two samples, at 0.001 µg/L. Analysis of sea water collected near the outfall of the wastewater discharges also showed the sporadic presence of 3 antibiotics (ciprofloxacin, clindamycin, trimethoprim) at low ng/L level, illustrating the impact of pharmaceuticals consumption and the poor removal of these compounds in conventional WWTPs. The most widespread antibiotic in sea water was ciprofloxacin, which was found in 15 out of 34 sea water samples analyzed, at concentrations ranging from 4 to 218 ng/L. Bacteria resistance was observed for some antibiotics identified in the samples (e.g. trimetropim and nalidixic acid -a first generation quinolone). However, resistance to some groups of antibiotics could not be correlated to their presence in the water samples due to analytical limitations (penicillins, tetraciclines). On the contrary, for some groups of antibiotics detected in samples (macrolides), the antibacterial activity against E. Coli was not investigated because these antibiotics do not include this bacterial species in their spectrum of activity. Our preliminary data demonstrate that antibiotics occurrence in the Antarctic aquatic environment is an issue that needs to be properly addressed. Periodical monitoring of water samples and the implementation of additional treatments in the WWTPs are recommended as a first step to prevent potential problems related to the presence of antibiotics and other emerging contaminants in the near future in Antarctica.

Swope Supernova Survey 2017a (SSS17a), the optical counterpart to a gravitational wave source.

On 17 August 2017, the Laser Interferometer Gravitational-Wave Observatory (LIGO) and the Virgo interferometer detected gravitational waves (GWs) emanating from a binary neutron star merger, GW170817. Nearly simultaneously, the Fermi and INTEGRAL (INTErnational Gamma-Ray Astrophysics Laboratory) telescopes detected a gamma-ray transient, GRB 170817A. At 10.9 hours after the GW trigger, we discovered a transient and fading optical source, Swope Supernova Survey 2017a (SSS17a), coincident with GW170817. SSS17a is located in NGC 4993, an S0 galaxy at a distance of 40 megaparsecs. The precise location of GW170817 provides an opportunity to probe the nature of these cataclysmic events by combining electromagnetic and GW observations.

Electromagnetic evidence that SSS17a is the result of a binary neutron star merger.

Eleven hours after the detection of gravitational wave source GW170817 by the Laser Interferometer Gravitational-Wave Observatory and Virgo Interferometers, an associated optical transient, SSS17a, was identified in the galaxy NGC 4993. Although the gravitational wave data indicate that GW170817 is consistent with the merger of two compact objects, the electromagnetic observations provide independent constraints on the nature of that system. We synthesize the optical to near-infrared photometry and spectroscopy of SSS17a collected by the One-Meter Two-Hemisphere collaboration, finding that SSS17a is unlike other known transients. The source is best described by theoretical models of a kilonova consisting of radioactive elements produced by rapid neutron capture (the r-process). We conclude that SSS17a was the result of a binary neutron star merger, reinforcing the gravitational wave result.

Light curves of the neutron star merger GW170817/SSS17a: Implications for r-process nucleosynthesis.

On 17 August 2017, gravitational waves (GWs) were detected from a binary neutron star merger, GW170817, along with a coincident short gamma-ray burst, GRB 170817A. An optical transient source, Swope Supernova Survey 17a (SSS17a), was subsequently identified as the counterpart of this event. We present ultraviolet, optical, and infrared light curves of SSS17a extending from 10.9 hours to 18 days postmerger. We constrain the radioactively powered transient resulting from the ejection of neutron-rich material. The fast rise of the light curves, subsequent decay, and rapid color evolution are consistent with multiple ejecta components of differing lanthanide abundance. The late-time light curve indicates that SSS17a produced at least ~0.05 solar masses of heavy elements, demonstrating that neutron star mergers play a role in rapid neutron capture (r-process) nucleosynthesis in the universe.

Convergence of mechanosensory inputs onto neuromodulatory serotonergic neurons in the leech.

By the frequency-dependent release of serotonin, Retzius neurons in the leech modulate diverse behavioral responses of the animal. However, little is known about how their firing pattern is produced. Here we have analyzed the effects of mechanical stimulation of the skin and intracellular stimulation of mechanosensory neurons on the electrical activity of Retzius neurons. We recorded the electrical activity of neurons in ganglia attached to their corresponding skin segment by segmental nerve roots, or in isolated ganglia. Mechanosensory stimulation of the skin induced excitatory synaptic potentials (EPSPs) and action potentials in both Retzius neurons in a ganglion. The frequency and duration of responses depended on the strength and duration of the skin stimulation. Retzius cells responded after T and P cells, but before N cells, and their sustained responses correlated with the activity of P cells. Trains of five impulses at 10 Hz in every individual T, P, or N cell in isolated ganglia produced EPSPs and action potentials in Retzius neurons. Responses to T cell stimulation appeared after the first impulse. In contrast, the responses to P or N cell stimulation appeared after two or more presynaptic impulses and facilitated afterward. The polysynaptic nature of all the synaptic inputs was shown by blocking them with a high calcium/magnesium external solution. The rise time distribution of EPSPs produced by the different mechanosensory neurons suggested that several interneurons participate in this pathway. Our results suggest that sensory stimulation provides a mechanism for regulating serotonin-mediated modulation in the leech.

Monoclonal antibodies to human apolipoproteins: application to the study of high density lipoprotein subpopulations.

We produced, selected and cloned hybridomas that secrete monoclonal antibodies against human apolipoprotein (apo) A-I. All of the antibodies corresponded to the IgG(1) subclass and were named 1C11, 2B4, 2C10, 7C5, 8A4 and 8A5. The antibodies were characterized by their reactivity with whole lipoproteins, apolipoproteins, synthetic peptides and fragments generated by cleavage of the apo A-I. Three of the monoclonal antibodies studied (2B4, 2C10 and 7C5) were similarly inhibited by an amino-terminal peptide (amino acid sequence 1-20) of apo A-I, whereas antibodies 1C11, 8A4 and 8A5 had no reaction. Other results show that monoclonal antibody 1C11 recognizes an epitope located between amino acids 135-148. We evaluated the monoclonal antibody 8A4 against different HDL subpopulations by competitive displacement analysis and it showed a similar reactivity with the HDL particles: LpA-I and LpA-I:A-II. This antibody was used to standardize a sandwich ELISA to quantitate LpA-I in plasma. We conclude that these monoclonal antibodies are relevant for the study of apo A-I epitope expression and for quantitating apo A-I containing lipoparticles.

[Lipoprotein particles LpA-I, LpA-I: A-II and LpB in coronary artery disease]. / Partículas lipoproteicas LpA-I, LpA-I: A-II y LpB en enfermedad coronaria.

BACKGROUND: High density lipoproteins are an heterogeneous population of particles. Two main subpopulations have been identified, one contains Apo A-I and Apo A-II and is denominated LpA-I:A-II and another one contains only Apo A-I and is denominated LpA-I. AIM: To measure the concentrations of these particles in patients with stable coronary artery disease. PATIENTS AND METHODS: Serum lipids, A-I and B apolipoproteins, LpA-I, LpA-I:A-II and LpB particles were measured in 73 men aged 33 to 82 years with angiographically documented coronary artery disease (CAD) and 33 control subjects aged 39 to 76 years. LpA-I, LpA-I:A-II and LpB were measured by a noncompetitive enzyme linked immunoassay using previously characterized monoclonal antibodies against ApoA-I, ApoA-II and apoB. RESULTS: Patients with CAD had significantly higher mean levels of LDL cholesterol than the control group (p = 0.038). The mean concentration of LpA-I particles in patients with CAD was significantly lower (p = 0.031) than in control subjects, while the concentration of LpA-I:A-II particles was significantly higher (p = 0.016). The percentage of coronary stenosis correlated negatively with LpA-I and positively with LpA-I:A-II. The best relative risk (RR) indicator in these patients was LDL-cholesterol. The relative risk increases 2.5 fold when LpA-I falls below the cut-off level. Likewise, the relative risk increases 3-fold when LpA-I:A-II raises over the cut-off level. CONCLUSIONS: Our findings indicate that the quantification of LpA-I and LpA-I:A-II particles might allow a more accurate evaluation of the CAD risk than HDL cholesterol. LpA-I might represent the antiatherogenic fraction of HDL.

Characterization of monoclonal antibodies against apolipoproteins A-I and A-II. Epitope expression in LpA-I and LpA-I:A-II particles.

Two monoclonal antibodies (MAbs) against apolipoprotein A-I (apo A-I), 6B9 and FF9B10, and one MAb against apolipoprotein A-II (apo A-II), 3F5, were characterized. To establish the epitope of apo A-I recognized by these antibodies, different experimental approaches were performed. First, competition between MAbs and the related epitopes on the same antigen was performed using double-determinant tests with previously characterized MAbs. Second, competition of different synthetic peptides of apo A-I in solution with apo A-I immobilized to solid phase was carried out. The MAbs against apo A-I (6B9 and FF9B10) appear to recognize discontinuous epitopes located in the amino-terminal region of the apo A-I. In competition experiments MAb 3F5 did not recognize central- or carboxy-terminal peptides of apo A-II. Furthermore, apo A-II was stronger recognized when it was included in HDL or LpA-I:A-II than in its purified form. So the epitope for 3F5 is better expressed in the lipoprotein structure. Finally, to establish the epitopes expression in different antigens in solution, competition of purified apo A-I, apo A-II, LpA-I, and LpA-I:A-II particles or HDL3, with apo A-I or HDL immobilized to solid phase, was carried out. The results showed that both MAbs against apo A-I reacted with poor affinity against free apo A-I, with high and similar affinities against Lp A-I and Lp A-I:A-II lipoparticles and with the highest affinity against HDL3. The MAb 3F5 against apo A-II recognized only LpA-I:A-II and not LpA-I lipoparticles.

An immunoenzymatic procedure for human apo B-containing particles quantification using monoclonal antibodies.

The present report describes a new monoclonal antibody-based enzyme immunoassay (ELISA) for the quantification of apolipoprotein (apo) B-containing particles in plasma. Native low-density lipoprotein (LDL) and a reference serum were utilized to prepare the standard curve. Three different antibodies to apo B-100--4A6E3, 6A10B10, and 2D9--all produced in our laboratory, were examined. The apparent affinity constants of the monoclonal antibodies (MAbs) 4A6E3, 6A10B10, and 2D9 were 2.9 x 10(9), 1.74 x 10(9), and 0.63 x 10(8), respectively. The standard curve was generated for an apo B-LDL range of 0.1 to 4.0 microg/ml. Evaluating the concentration of apo B-containing particles in plasma may allow for a more accurate assessment of the risk of coronary artery disease.

Increased activity of lecithin:cholesterol acyltransferase during short-term oral estrogen progestin replacement therapy in a group of postmenopausal women.

The aim of the study was to assess the short-term effect of estrogen-progestin therapy on the plasma level of lecithin: cholesterol acyltransferase ([LCAT] EC 2.3.1.43), a key enzyme in the cholesterol reverse-transport process. The trial included 21 women with at least 6 months of menopause, which was confirmed by anamnesis, physical evaluation, and follicle-stimulating hormone (FSH) determination. Women receiving pharmacological treatment or who had any kind of endocrine disorder were excluded. In addition, we evaluated and confirmed normal Papanicolaou and mammography tests in all 21 women included in the trial. They received conjugated equine estrogen 0.625 mg daily, plus cyclic medroxyprogesterone acetate (5 mg daily) for 12 days each month. Plasma levels of LCAT, cholesterol, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), triglycerides, apoB, and apoAI were evaluated before and after 1 and 3 months of therapy. Pretherapy and posttherapy results were analyzed statistically by Wilcoxon's rank-sum test for paired samples. No significant changes were observed either for body mass index or for blood pressure. A significant increase in plasma LCAT activity was found at the first and third month posttherapy (P < .005). In addition, after 3 months of therapy, HDL-C significantly increased (P < .005), in contrast to the significant decrease detected in total cholesterol (P < .025), LDL-C (P < .005), cholesterol to HDL-C and LDL-C/HDL-C ratios (P < .005). Triglyceride levels did not show significant modification. In conclusion, our results indicate that short-term estrogen-progestin therapy produces a significant increase in plasma LCAT activity, as well as beneficial changes in the lipid profile, in postmenopausal women.

A monoclonal antibody-based enzyme immunoassay for the measurement of native and glycated apolipoprotein B-containing particles.

We describe the development of sandwich enzyme-linked immunosorbent assays designed to measure native and glycated apolipoprotein B containing particles in plasma. The assays utilize monoclonal antibodies anti native or glycated apo B-LDL for coating and a polyclonal anti apoB-LDL-peroxidase conjugate as the detecting antibody. The method is specific, sensitive and precise. The intra assay coefficient of variation for the plasma native and glycated apolipoprotein B-containing particles was determine to be 7.8% and 7.5%, respectively. The method described can provide specific and reproducible determinations of apoB and glycated-apoB containing particles in plasma; it will be of great interest in the evaluation of atherosclerotic risk in dyslipoproteinemic states in diabetic and non-diabetic subjects.

Influencia de la etnia sobre los niveles de Lp(a) y sus isoformas / Influence of the ethnic origin on Lp(a) serum levels and its isoforms

Se midieron las concentraciones séricas y la distribución de frecuencia de lipoproteína (a) en 71 niños caucásicos y 41 pehuenches (de 6 a 15 años de edad) que habitan en la zona del Alto Bío-Bío, VIII Región geopolítica de Chile. Adicionalmente se registraron las isoformas de apolipoproteína (a) en 50 de los participantes. Las concentraciones de lipoproteína (a) fueron 10,5 ñ 6,2 y 21,3 ñ 34,5 mg/dl, respectivamente, en los niños pehuenches y caucásicos (p< 0,001). La distribución de las frecuencias de ambos grupos mostró inclinación hacia las concentraciones más bajas de una curva normal. La prevalencia de concentraciones séricas de lipoproteína (a) consideradas riesgosas en términos de enfermedades cardiovasculares (> 30 mg/dl) fue de 21,1 por ciento y 7,3 por ciento, respectivamente, para niños caucásicos y pehuenches. En los caucásicos se observó una correlación inversa entre el tamaño de la isoforma de apolipoproteína (a) y la concentración plasmática de lipoproteína (a) (r=0,77), lo que fue menos claro en la población pehuenche (r=0,33)

[Lipoprotein in children and adolescents: relationship with family history of coronary artery disease]. / Lipoproteína en niños y adolescentes: relación con historia familiar de enfermedad coronaria.

BACKGROUND: Lipoprotein (a) is considered an independent cardiovascular risk factor. AIM: To study lipoprotein (a) levels in children of 18 years old or less with or without family history of coronary artery disease. SUBJECTS AND METHODS: Forty four children aged between 3 and 18 years old with a family history of coronary artery disease and 44 age and sex matched controls were studied. A fasting blood sample was obtained to measure total, HDL and LDL cholesterol, triglycerides, A1 and B apoproteins and lipoprotein (a). RESULTS: Compared to controls, children with a family history of coronary disease had higher total cholesterol (177 +/- 35 and 159 +/- 23 mg/dl respectively), LDL cholesterol (112 +/- 34 and 94 +/- 21 mg/dl respectively), triglycerides (89 +/- 38 and 71 +/- 25 mg/dl respectively), apoprotein B (85 +/- 17 and 65 +/- 13 mg/dl respectively) and lipoprotein (a) (40 +/- 50 and 22 +/- 31 mg/dl respectively). Thirty two percent of children with positive family history had lipoprotein (a) levels over 30 mg/dl, compared to 23% of controls. CONCLUSIONS: Children with family history of coronary artery disease have higher levels of cholesterol, triglycerides and lipoprotein (a) than matched controls.

Lipoproteína en niños y adolescentes: relación con historia familiar de enfermedad coronaria / Lipoprotein in children and adolescents: relation with familiar history of coronary disease

Lipoprotein(a) is considered an independent cardiovascular risk factor. Forty four children aged between 3 and 18 years old with family history of coronary artery disease and 44 age and sex matched controls were studied. A fasting blood sample was obtained to measure total, HDL and LDL, cholesterol, triglycerides. A1 and B apoproteins and lipoprotein (a). Comparaed to controls, children with family history of coronary disease had higher total cholesterol (177ñ35 and 159ñ23 mg/dl respectively). LDL cholesterol (112ñ34 and 94ñ21 mg/dl respectively), triglycerides (89ñ38 and 71ñ25 mg/dl respectively), apoprotein B (85ñ17 and 65ñ13 mg/dl respectively), and lipoprotein (a) (40ñ50 and 23ñ31 mg/dl respectively). Thirty two percent of children with positive family history had lipoprotein (a) levels over 30 mg/dl, compared to 23 percent of controls. Children with family history of coronary artery disease have higher levels of cholesterol, triglycerides and lipoprotein (a) than matched controls

Development of monoclonal antibodies for the selective isolation of human plasma apolipoprotein A-containing particles.

Monoclonal antibodies (MAbs) to human plasma apolipoprotein A-I (apo A-I), denoted FF9 and 6B9, and apolipoprotein A-II (apo A-II), 3F5, were developed to be used in an immunoaffinity chromatography procedure to isolate lipoprotein particles Lp A-I and Lp A-I:A-II. MAb FF9 and MAb 6B9 reacted with apo A-I and high-density lipoprotein (HDL) while MAb 3F5 was directed to apo A-II and HDL. The apparent affinity constant (Kapp) for apo A-I of the MAb FF9 was higher (2 x 10(7) M-1) than that of 6B9 (5 x 10(6) M-1). MAb 3F5 recognized the apo A-II with a Kapp value of 1 x 10(9) M-1. The isolated lipoparticles Lp A-I and Lp A-I:A-II will be used to standardize an immunoassay for the measurement of these apo A-I-containing lipoprotein particles in human plasma.

A single intravenous high dose of cholic acid to a pregnant ewe does not affect fetal well-being.

Cardiovascular variables of both mother and fetus and total bile acid levels were monitored in amniotic fluid and in maternal and fetal plasma after the administration of a single intravenous high dose (29 mg) of cholic acid to a pregnant ewe. We observed the diffusion of significant quantities of cholic acids from the mother to the fetus and amniotic fluid. Nevertheless, cardiovascular parameters (heart rate, blood pressure, PO2, PCO2 and pH) were not affected, neither did intra-amniotic pressure show significant changes compared with the initial experimental conditions. It is concluded that an acute increase in maternal plasma levels of bile acids does not produce important adverse effects in either the mother animal or the fetus and consequently, if bile acids should be deemed responsible for any deleterious effect observed in a preterm fetus in intrahepatic cholestasis, this should be considered as the consequence of a chronic process.