Multi-analytical characterization of an oncoid from a high altitude hypersaline lake using techniques employed in the Mars2020 and Rosalind Franklin missions on Mars.

In this work, a geological sample of great astrobiological interest was studied through analytical techniques that are currently operating in situ on Mars and others that will operate in the near future. The sample analyzed consisted of an oncoid, which is a type of microbialite, collected in the Salar Carachi Pampa, Argentina. The main peculiarity of microbialites is that they are organo-sedimentary deposits formed by the in situ fixation and precipitation of calcium carbonate due to the growth and metabolic activities of microorganisms. For this reason, the Carachi Pampa oncoid was selected as a Martian analog for astrobiogeochemistry study. In this sense, the sample was characterized by means of the PIXL-like, SuperCam-like and SHERLOC-like instruments, which represent instruments on board the NASA Perseverance rover, and by means of RLS-like and MOMA-like instruments, which represent instruments on board the future ESA Rosalind Franklin rover. It was possible to verify that the most important conclusions and discoveries have been obtained from the combination of the results. Likewise, it was also shown that Perseverance rover-like remote-sensing instruments allowed a first detailed characterization of the biogeochemistry of the Martian surface. With this first characterization, areas of interest for in-depth analysis with Rosalind Franklin-like instruments could be identified. Therefore, from a first remote-sensing elemental identification (PIXL-like instrument), followed by a remote-sensing molecular characterization (SuperCam and SHERLOC-like instruments) and ending with an in-depth microscopic analysis (RLS and MOMA-like instruments), a wide variety of compounds were found. On the one hand, the expected minerals were carbonates, such as aragonite, calcite and high-magnesium calcite. On the other hand, unexpected compounds consisted of minerals related to the Martian/terrestrial surface (feldspars, pyroxenes, hematite) and organic compounds related to the past biological activity related to the oncoid (kerogen, lipid biomarkers and carotenes). Considering samples resembling microbialites have already been found on Mars and that one of the main objectives of the missions is to identify traces of past life, the study of microbialites is a potential way to find biosignatures protected from the inhospitable Martian environment. In addition, it should be noted that in this work, further conclusions have been obtained through the study of the results as a whole, which could also be carried out on Mars.

Sustained zero-order delivery of GC-1 from a nanochannel membrane device alleviates metabolic syndrome.

BACKGROUND/OBJECTIVES: Our objective was to assess the sustained, low-dose and constant administration of the thyroid receptor-ß (TRß)-selective agonist GC-1 (sobetirome) from a novel nanochannel membrane device (NMD) for drug delivery. As it known to speed up metabolism, accomplish weight loss, improve cholesterol levels and possess anti-diabetic effects, GC-1 was steadily administered by our NMD, consisting of an implantable nanochannel membrane, as an alternative to conventional daily administration, which is subject to compliance issues in clinical settings. SUBJECTS/METHODS: Diet-induced obese C57BL/J6 male mice were fed a very high-fat diet (VHFD) and received NMD implants subcutaneously. Ten mice per group received capsules containing GC-1 or phosphate-buffered saline (control). Weight, lean and fat mass, as well as cholesterol, triglycerides, insulin and glucose, were monitored for 24 days. After treatment, plasma levels of thyroid-stimulating hormone (TSH) and thyroxine were compared. mRNA levels of a panel of thermogenic markers were examined using real-time PCR in white adipose tissue (WAT) and brown adipose tissue (BAT). Adipose tissue, liver and local inflammatory response to the implant were examined histologically. Pancreatic islet number and ß-cell area were assessed. RESULTS: GC-1 released from the NMD reversed VHFD-induced obesity and normalized serum cholesterol and glycemia. Significant reductions in body weight and fat mass were observed within 10 days, whereas reductions in serum cholesterol and glucose levels were seen within 7 days. The significant decrease in TSH was consistent with TRß selectivity for GC-1. Levels of transcript for Ucp1 and thermogenic genes PGC1a, Cidea, Dio2 and Cox5a showed significant upregulation in WAT in NMD-GC-1-treated mice, but decreased in BAT. Although mice treated by NMD-GC-1 showed a similar number of pancreatic islets, they exhibited significant increase in ß-cell area. CONCLUSIONS: Our data demonstrate that the NMD implant achieves steady administration of GC-1, offering an effective and tightly controlled molecular delivery system for treatment of obesity and metabolic disease, thereby addressing compliance.

Soybean fungal soil-borne diseases: a parameter for measuring the effect of agricultural intensification on soil health.

The aim of this study was to investigate the influence of agricultural intensification on soil microbial diversity, chemical and physical parameters, and the decrease of the incidence of sudden death syndrome (Fusarium crassistipitatum) and charcoal rot (Macrophomina phaseolina) in soybean. Soils under different management systems were evaluated during 2 crop cycles: soybean monoculture for 24 and 11 years, soybean-maize rotation for 15 and 4 years, 1 year of soybean, and native vegetation. The incidence of both soil-borne diseases was higher under monoculture than under rotation. Increased populations of potential biocontrol agents (Trichoderma spp., Gliocladium spp., fluorescent pseudomonads) were associated with rotation treatments, especially in 2010-2011. The comparison of agricultural vs. native vegetation soil and the average of agricultural cycles showed that microbial biomass carbon and glomalin-related soil protein were higher in the rotation system than in monoculture (50% and 77%, respectively). Furthermore, from the community-level functional diversity (Biolog Eco plates), McIntosh index showed lower functional diversity in monoculture than in rotation and native vegetation plots. Agricultural intensification reduced microbial biomass carbon, glomalin-related soil protein, organic matter, total nitrogen, aggregate stability, and yield, and increased bulk density. Soil quality degradation was associated with the establishment of soil-borne pathogens and increased soybean plant susceptibility to disease.

Alpaca semen characteristics previous to a mating period.

Increasing the knowledge of the semen characteristics in the alpaca will contribute to understanding one of the many factors that affect the poor fertility rate in this species. Ten adult male alpacas, 2.6-10 years of age, average weight 64.7 +/- 4.7 kg were used. The animals were distributed randomly into two groups of five each and submitted alternatively to two semen collections, using an artificial vagina and sexually receptive females. For the first semen collection the animals had a sexual rest period of about 90 and 45 days before the second. Duration of semen collection, color and volume of ejaculate were recorded, and sperm concentration and morphology (light microscopy) were evaluated. Descriptive statistical analyses were used for each variable, considering all samples obtained (n= 19). An analysis of variance for animal groups and opportunity of collection were used for quantitative variables. Most frequent color was opalescent white (84.2%). There were no statistical differences among male groups or between semen collections. The average values and standard deviations for the quantitative variables were: 12.3 +/- 7.2 min for semen collection time, 1.8 +/- 0.8 ml for ejaculate volume, (17.6 +/- 26.1) x 10(6) sperm/ml for sperm concentration and 34.0 +/- 52.2 x 10(6) for total number of sperm per ejaculate. The percentage of normal spermatozoa was 51.0 +/- 12.4%. From the total abnormalities, that of mid piece segment (14.4%) was the most frequent. These results indicate that male alpaca have poor semen quality, when compared with other domestic species. Nevertheless, for the evaluation of male alpaca as breeders it would be necessary to create a protocol for the selection of them, where phenotypic, behavioral and seminogram aspects are considered. The values reported herein define the characteristics of the alpaca semen that could be considered as the initial base of the seminal analysis to select male alpacas before mating.

Determination of polarimetric parameters of honey by near-infrared transflectance spectroscopy.

NIR transflectance spectroscopy was used to determine polarimetric parameters (direct polarization, polarization after inversion, specific rotation in dry matter, and polarization due to nonmonosaccharides) and sucrose in honey. In total, 156 honey samples were collected during 1992 (45 samples), 1995 (56 samples), and 1996 (55 samples). Samples were analyzed by NIR spectroscopy and polarimetric methods. Calibration (118 samples) and validation (38 samples) sets were made up; honeys from the three years were included in both sets. Calibrations were performed by modified partial least-squares regression and scatter correction by standard normal variation and detrend methods. For direct polarization, polarization after inversion, specific rotation in dry matter, and polarization due to nonmonosaccharides, good statistics (bias, SEV, and R(2)) were obtained for the validation set, and no statistically (p = 0.05) significant differences were found between instrumental and polarimetric methods for these parameters. Statistical data for sucrose were not as good as those of the other parameters. Therefore, NIR spectroscopy is not an effective method for quantitative analysis of sucrose in these honey samples. However, NIR spectroscopy may be an acceptable method for semiquantitative evaluation of sucrose for honeys, such as those in our study, containing up to 3% of sucrose. Further work is necessary to validate the uncertainty at higher levels.

Evolution of invertase activity in honey over two years.

Invertase activity is a good parameter for evaluating honey freshness. Invertase activity evolution was determined on 57 fresh, unheated, commercially purchased Galician (northwestern Spain) floral honey samples. All honeys were stored in darkness at room temperature for up 24 months and analyzed each 6 months so as to determine the invertase activity evolution tendency for the first time. Invertase activity analysis was carried out according to Siegenthaler's method and in a simple assay, the latter showing a good precision (coefficient of variation between 0.35 and 0.66%). Initial invertase activity mean value was 163.9 (48.4-251.0) micromol of 4-nitrophenyl-alpha-D-glucopyranoside hydrolyzed/kg of honey/min. After application of the SPSS statistical package, the values of invertase activity showed five types of temporal behavior: exponential (56% of samples), linear (25% of samples), logarithmic (11% of samples), inverse (5% of samples), and quadratic (3% of samples). Linear regression equations were used to predict the invertase activity at 6, 12, 18, and 24 months from the initial Galician honeys' invertase activities; no statistical differences were found between experimental data and the activities calculated from the linear regression equations.

Major components of honey analysis by near-infrared transflectance spectroscopy.

NIR transflectance spectroscopy was used to analyze fructose, glucose, and moisture in honey. A total of 161 honey samples were collected during 1992 (46), 1995 (58), and 1996 (57). Samples were analyzed by instrumental, enzymatic (fructose and glucose), and refractometric (moisture) methods. Initially, different calibrations were performed for each of the 3 years of sampling. Good predictions were obtained for all three components with equations of the particular year. But good predictions were not always obtained when the equations calculated one year were applied to samples from another year. To perform a lasting calibration, unique calibration (121 samples) and validation (40 samples) sets were built; honeys of the 3 years were included in both sets. Good statistics (bias, standard error of validation (SEV), and R(2)) were obtained for all three components of the validation set. No statistically significant differences (p = 0.05) were found between instrumental and reference methods.

[The scope of moral responsibility due to therapeutic actions]. / Alcances de la responsabilidad moral por la acción terapéutica.

Besides utilitarianism, there are different ways to understand Medicine and its role. The opinion of the author is that the pursuit of mankind welfare is not the role of physicians and that their responsibility is not referred to the world. On the contrary, their bumble mission is to cure or mitigate pain through therapeutic actions. Any other way of proceeding means that the medical action is becoming orchestrated, destroying the fundamental value of patient physician relationship. This article intends to demonstrate the insufficiency of the Aristotelian idea of technique applied to medicine and that, on the other hand, the modern ideal of a principle free science does not account for the complexity of medical practice, mainly in the field of Psychiatry. Finally the author wonders if the moral convictions of physicians may play a role in the treatment of specific diseases caused by morally inadequate behaviors.

Acaricide residues in honeys from Galicia (N.W. Spain).

Honey samples (101) from Galicia (N.W. Spain) were analyzed by gas chromatography (electron capture and flame ionization) for the presence of acaricides (amitraz, bromopropylate, coumaphos, and fluvalinate). Seventy-three samples were free from detectable residues. Bromopropylate residues were found in 16 samples in levels ranging from 5 to 60 microg/kg. Fluvalinate residues were found in 11 samples in levels ranging from 10 to 40 microg/kg. One sample contained 100 microg of fluvalinate per kg. Neither amitraz nor coumaphos residues were detected.

Histology of the mucosa of the oesophagogastric junction and the stomach in adult Rana perezi.

The histological structure of the frog digestive mucosa changes at the oesophagogastric junction. The pseudostratified ciliated mucosal epithelium of oesophageal type changes to a simple mucus-secreting epithelium of gastric type. The glands straighten and the muscularis mucosae develops as a complete layer. The muscularis increases in thickness. Unlike the mammalian stomach, in the frog the surface of the plicae forms convoluted ridges that delimit furrow-shaped pits. Two types of gastric glands are distinguished, fundal and pyloric. The former consist of mucous, oxynticopeptic and endocrine cells. The pyloric glandular cells are mainly of mucus-secreting type with scattered endocrine cells. Scattered endocrine cells of P, D, G, A, EC, and EC-L-like types are found in the glands along the stomach. It is concluded that the mucosal structure of the anuran oesophagogastric junction and stomach is less complicated than that of mammals, including man.

Abnormal spermatozoa in the cauda epididymidis of adult and aged hamsters (Mesocricetus auratus): a study by electron microscopy.

The morphology of the spermatozoa in the cauda epididymidis of 6- and 24-month-old (adult and aged) hamster was studied by electron microscopy. Lesions found in the spermatozoa included alterations in the acrosomal matrix and nuclear membranes, abnormal or absent mitochondria, alterations in the axonemes, dense fibres and microtubules, and bent flagella. All these abnormalities are similar to those found in other species and few alterations were exclusive to the older animals. Ultrastructurally abnormal spermatozoa were observed in both groups but were present at a significantly greater frequency in aged hamsters (p < 0.005). the percentage of sperm with abnormal acrosomes, mitochondria and dense fibres and of bent (but not disrupted) spermatozoa was significantly greater in the older animals. These results show that the ultrastructural alterations in hamster sperm are similar to those found in other mammals. Moreover, the percentage of ultrastructurally abnormal spermatozoa in aged hamsters is greater than 6-month-old hamsters, this increase is not accompanied by any new kinds of alteration.

Nonacaricide Pesticide Residues in Honey: Analytical Methods and Levels Found.

A bibliographic review on honey pollution with pesticides is presented. This paper reviews the methods set up for determining pesticide residues in honey samples as well as the pesticide residue levels found in European countries.

Acaricide Residues in Honey: Analytical Methods and Levels Found.

A bibliographic review on the pollution of honey with acaricides is presented. This paper reviews methods for determining amitraz, bromopropylate, coumaphos, cymiazole, fluvalinate, malathion and phenothiazine residues in honey samples, as well as multiresidue methods. Acaricide residue levels found in European countries are also reviewed.

Histochemical study of glycoconjugates in the nasal mucosa of the rat and guinea pig.

A histochemical study was carried out on the glycoconjugates of the nasal mucosa of rat and guinea pig using conventional techniques and peroxidase-labelled lectins. Both the respiratory mucosa and neuroepithelium were studied. Sulphate and sialic acid groups were found in the mucous layer of the neuroepithelia, Bowman's glands and goblet cells. In contrast, the nasal glands did not possess these groups, and only a few showed neutral mucins. Carbohydrate residues were more numerous in the acini of the Jacobson glands. Thus, the nasal glands in the rat and guinea pig are probably of a serous type because of the scarcity of carbohydrate residues.

Histology of the esophagus of the adult frog Rana perezi (Anura: Ranidae).

Study of the esophageal microscopic morphology of adult Rana perezi by light and electron microscopy discloses some large folds throughout the esophagus that are in themselves ringed. Glandular ostia open in the furrows of the luminal surface. The esophageal wall is made up of a connective adventitia rich in melanocytes, a muscular tunica, a connective and glandular subepithelial layer, and a pseudostratified ciliated epithelium. This epithelium basically consists of ciliated, goblet, basal, microvillous-apex, and migratory cells. Two types of goblet cells are distinguished with regard to the granular ultrastructure. The microvillous-apex cell has not been found in other amphibians. It shows a very differentiated morphology with a high number of mitochondria. The basal cells give the epithelium a pseudostratified morphology, and they have a proliferative function. Glands are branched and drain through an excretory duct that has a monolayered mucosecreting epithelium. The glandular units are formed by two principal types of cells: mucosecretory and serous.