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Staphylococcus aureus is an opportunistic pathogen that is considered a global health threat. This microorganism can adapt to hostile conditions by regulating membrane lipid composition in response to external stress factors such as changes in pH and ionic strength. S. aureus synthesizes and incorporates in its membrane staphyloxanthin, a carotenoid providing protection against oxidative damage and antimicrobial agents. Staphyloxanthin is known to modulate the physical properties of the bacterial membranes due to the rigid diaponeurosporenoic group it contains. In this work, preparative thin layer chromatography and liquid chromatography mass spectrometry were used to purify staphyloxanthin from S. aureus and characterize its structure, identifying C15, C17 and C19 as the main fatty acids in this carotenoid. Changes in the biophysical properties of models of S. aureus membranes containing phosphatidylglycerol, cardiolipin, and staphyloxanthin were evaluated. Infrared spectroscopy shows that staphyloxanthin reduces the liquid-crystalline to gel phase transition temperature in the evaluated model systems. Interestingly, these shifts are not accompanied by strong changes in trans/gauche isomerization, indicating that chain conformation in the liquid-crystalline phase is not altered by staphyloxanthin. In contrast, headgroup spacing, measured by Laurdan GP fluorescence spectroscopy, and lipid core dynamics, measured by DPH fluorescence anisotropy, show significant shifts in the presence of staphyloxanthin. The combined results show that staphyloxanthin reduces lipid core dynamics and headgroup spacing without altering acyl chain conformations, therefore decoupling these normally correlated effects. We propose that the rigid diaponeurosporenoic group in staphyloxanthin and its positioning in the membrane is likely responsible for the results observed.

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Much research has been carried out to remove emerging contaminants using diverse materials. Furthermore, studies related to pollutant degradation have increased over the past decade. Mechanochemical degradation can successfully decompose molecules that are persistent in the environment. In this study, the biochar of fique bagasse with mixtures SiO2, Al, Al2O3, and Al-Al2O3 was treated with a mechanochemical technique using a planetary ball mill to investigate the degradation of caffeine and diclofenac. These tests resulted in the transformation of caffeine and diclofenac due to the use of Al employing mechanochemistry. In fact, through the use of liquid chromatography coupled with mass spectrometry, eight and six subproducts were identified for caffeine and diclofenac, respectively. Additionally, analysis of the molecules proposed for caffeine and diclofenac transformation suggested hydroxylation, demethylation, decarboxylation, oxidation reactions, and cleavage of the C-C and C-N bonds in the pollutants studied. The formation of these transformation products could be possible by reductant oxygen species generated from the molecular oxygen in the presence of aluminum and the energy delivered for ball milling. The results obtained show the potential application in the environmental management of mechanochemical treatment in the elimination of emerging contaminants caffeine and diclofenac.

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Staphylococcus aureus membranes contain carotenoids formed during the biosynthesis of staphyloxanthin. These carotenoids are considered virulence factors due to their activity as scavengers of reactive oxygen species and as inhibitors of antimicrobial peptides. Here, we show that the growth of S. aureus under oxygen-restricting conditions downregulates carotenoid biosynthesis and modifies phospholipid content in biofilms and planktonic cells analyzed using LC-MS. At oxygen-restrictive levels, the staphyloxanthin precursor 4,4-diapophytofluene accumulates, indicating that the dehydrogenation reaction catalyzed by 4,4'-diapophytoene desaturases (CrtN) is inhibited. An increase in lysyl-phosphatidylglycerol is observed under oxygen-restrictive conditions in planktonic cells, and high levels of cardiolipin are detected in biofilms compared to planktonic cells. Under oxygen-restriction conditions, the biophysical parameters of S. aureus membranes show an increase in lipid headgroup spacing, as measured with Laurdan GP, and decreased bilayer core order, as measured with DPH anisotropy. An increase in the liquid-crystalline to gel phase melting temperature, as measured with FTIR, is also observed. S. aureus membranes are therefore less condensed under oxygen-restriction conditions at 37 °C. However, the lack of carotenoids leads to a highly ordered gel phase at low temperatures, around 15 °C. Carotenoids are therefore likely to be low in S. aureus found in tissues with low oxygen levels, such as abscesses, leading to altered membrane biophysical properties.

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Sustainable management of non-edible agricultural residues of cashew nut production is a concern in Colombia. Therefore, this study aimed to study the fatty acid content of a pyrolytic liquid obtained from cashew nut shells (CNSs) from the Vichada region in Colombia. Transesterification of pyrolytic liquid was conducted to obtain biodiesel at the micro-scale as the first approach for this valorization route. Proximal analysis of samples was carried out using advanced analytical techniques (UHPLC-MS and CG-MS) whereas phenolic content and antioxidant activity were determined. The production yield of pyrolytic liquid was 69.15 ± 5.07% weight (wt.), at 550 °C and 2h of pyrolysis and the liquid was rich in fatty acids (∼70% wt.) and long-chain phenols (∼18% wt.). Among the phenolic compounds in liquid, mainly unsaturated C15:4 cardanol was identified (82.1 ± 5.5 mg/g), whereas the antioxidant activity of pyrolytic liquid was 0.714 ± 0.030 TE/g. Moreover, the biodiesel yield was 81% using catalyst sodium methoxide (12% v), and 50 °C and 26 min for the reaction. The obtained biodiesel in the hexane fraction was rich in methyl trans-8-octadecanoate (20.9 % wt.) and methyl palmitate (14.3 % wt.), being the representative compounds in the biodiesel. Therefore, the results indicated that thermal conversion of CNSs for obtaining biodiesel on a one-step process is a suitable strategy for the management of toxic and non-edible cashew residues. Finally, this is the first work of its kind that propose in detail the composition of pyrolytic liquid obtained from Colombian cashew nut residues under the proximate analysis approach and using advanced analytical techniques.

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La adicción a las redes sociales potencia las probabilidades de infidelidad de pareja. Esta investi-gación tuvo el objetivo de determinar la relación entre conducta infiel y adicción a redes sociales en adultos de las áreas comerciales de Tarapoto, Lamas, San José de Sisa, Moyobamba y Naran-jos, región de la Amazonía Peruana, durante el primer cuatrimestre de 2021. Así, se desarrolló un estudio con diseño no experimental y tipo de investigación correlacional, en una muestra de 318 individuos con edades entre 20 y 40 años, a los que se aplicó el Inventario Multidimensional de Infidelidad y el Cuestionario de Adicción a Redes Sociales. El 62,3% de los participantes perteneció al sexo masculino, el 57,5% tenía edades entre 30 y 59 años, el 66,7% convivía con sus parejas sin estar casados y el 51,6% se encontraban en la segunda etapa de la relación de pareja. Existieron diferencias significativas entre hombres y mujeres en cuanto a la conducta infiel (U=6387,500; p<0,000). En este contexto, se observó un predominio del nivel medio de la adición a las redes sociales en los participantes y del bajo en las dimensiones de la conducta de infidelidad, estableciéndose correlación estadísticamente significativa entre ambas variables.

Addiction to social networks increases the chances of partner infidelity. This research aimed to determine the relationship between unfaithful behavior and addiction to social networks in adults from the commercial areas of Tarapoto, Lamas, San José de Sisa, Moyobamba, and Naranjos, in the Peruvian Amazon region, during the first four-month period of 2021. Thus, a study with a non-experimental design and correlational research type was developed in a sample of 318 individuals between 20 and 40 years old. The Multidimensional Infidelity Inventory and the Social Networks Addiction Questionnaire were applied. 62.3% of the participants were male, 57.5% were between 30 and 59 years old, 66.7% lived with their partners without marria-ge, and 51.6% were in the second stage of the couple relationship. There were significant diffe-rences between men and women regarding unfaithful behavior (U=6387,500; p<0.000). In this context, a predominance of the medium level of addiction to social networks in the participants and the low level in the dimensions of infidelity behavior were observed, establishing a statisti-cally significant correlation between both variables.

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Natural carotenoids are secondary metabolites that exhibit antioxidant, anti-inflammatory, and anti-cancer properties. These types of compounds are highly demanded by pharmaceutical, cosmetic, nutraceutical, and food industries, leading to the search for new natural sources of carotenoids. In recent years, the production of carotenoids from bacteria has become of great interest for industrial applications. In addition to carotenoids with C40-skeletons, some bacteria have the ability to synthesize characteristic carotenoids with C30-skeletons. In this regard, a great variety of methodologies for the extraction and identification of bacterial carotenoids has been reported and this is the first review that condenses most of this information. To understand the diversity of carotenoids from bacteria, we present their biosynthetic origin in order to focus on the methodologies employed in their extraction and characterization. Special emphasis has been made on high-performance liquid chromatography-mass spectrometry (HPLC-MS) for the analysis and identification of bacterial carotenoids. We end up this review showing their potential commercial use. This review is proposed as a guide for the identification of these metabolites, which are frequently reported in new bacteria strains.

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Staphylococcus aureus (S. aureus) is a pathogenic gram-positive bacterium that normally resides in the skin and nose of the human body. It is subject to fluctuations in environmental conditions that may affect the integrity of the membrane. S. aureus produces carotenoids, which act as antioxidants. However, these carotenoids have also been implicated in modulating the biophysical properties of the membrane. Here, we investigate how carotenoids modulate the thermotropic phase behavior of model systems that mimic the phospholipid composition of S. aureus. We found that carotenoids depress the main phase transition of DMPG and CL, indicating that they strongly affect cooperativity of membrane lipids in their gel phase. In addition, carotenoids modulate the phase behavior of mixtures of DMPG and CL, indicating that they may play a role in modulation of lipid domain formation in S. aureus membranes.

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Multidrug-resistant tuberculosis (isoniazid/rifampin[RIF]-resistant TB) ravages developing countries. Fitness is critical in clinical outcomes. Previous studies on RIF-resistant TB (RR-TB) showed competitive fitness gains and losses, with rpoB-S450L as the most isolated/fit mutation. This study measured virulence/resistance genes, phthiocerol dimycocerosate (PDIM) levels and their relationship with rpoB S450L ATCC25618 RR-TB strain fitness. After obtaining 10 different RR-TB GenoType MTBDRplus 2.0-genotyped isolates (with nontyped, S441, H445 and S450 positions), only one S450L isolate (R9, rpoB-S450L ATCC 25618, RR 1 µg/mL) was observed, with H445Y being the most common. A competitive fitness in vitro assay with wild-type (wt) ATCC 25618: R9 1:1 in 50 mL Middlebrook 7H9/OADC was performed, and generation time (G) in vitro and relative fitness were obtained. mRNA and PDIM were extracted on log and stationary phases. Fitness decreased in rpoB S450L and H445Y strains, with heterogeneous fitness cues in three biological replicas of rpoB-S450L: one high and two low fitness replicas. S450L strain had significant pknG increase. Compared with S450L, wt-rpoB showed increased polyketide synthase ppsA expression and high PDIM peak measured by HPLC-MS in log phase compared to S450L. This contrasts with previously increased PDIM in other RR-TB isolates.

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Introducción: El síndrome de ojo seco es una enfermedad subdiagnosticada. El método diagnóstico más utilizado es la medición del tiempo de rotura de la lágrima con fluoresceína (TRLf). Sin embargo, no hay una prueba de referencia.­ Objetivo: Estimar la correlación del TRLf y el tiempo de rotura lagrimal no invasivo (TRLNI) con el puntaje del cuestionario OSDI (Ocular Surface Disease Index). Método: Estudio transversal. Se incluyeron 60 ojos de 30 pacientes mayores de edad que asistían a consulta de oftalmología en una clínica especializada de Cali, Colombia. Se recolectó por medio del cuestionario OSDI la sintomatología asociada y se tomó el TRLNI con el topógrafo corneal por personal calificado. El TRLf se tomó de la historia clínica. Se realizaron correlaciones con método de Kendall, Kappa y Spearman. Resultados: La mediana del TRLf para el ojo derecho (OD) fue de 15.2 s (6.4-22.4) y para el ojo izquierdo (OI) de 15.3 s (6.2-22.6). La mediana del TRLNI para el OD fue de 7.5 s (2.6-17.7) y para el OI de 6.7 s (1.4-17.1). El 36.6% de los pacientes presentaron TRLf < 10 s y el 70.0% por TRLNI. El coeficiente de correlación de Kendall mostró OD tau-b 0,2966 y OI tau-b 0,3065. La correlación del puntaje OSDI y el tiempo de rotura de la lágrima fue negativa, pero no significativa. Conclusiones: El TRLNI fue más corto que el TRLf. La correlación del puntaje del cuestionario OSDI fue moderada para ambos métodos.

Introduction: Dry eye syndrome is a sub diagnose disease. The diagnostic method most commonly used is the fluorescein tear break up time (fBUT). However, there is no gold test. Objective: To estimate the correlation of fBUT, non-invasive tear break up time (NIBUT) and with the score of the Ocular Surface Disease Index (OSDI). Method: Cross-sectional study. 60 eyes of 30 adult patients attending an ophthalmology clinic in Cali, Colombia were included. The associated symptomatology was collected through the OSDI questionnaire and the NIBUT was taken with the corneal topograph by qualified personnel. The fBUT was taken from the medical records. Correlations were made with the method of Kendall, Kappa and Spearman. Results: The median fBUT for the right eye (OD): 15.2 (6.4-22.4 s) and left eye (OS): 15.3 (6.2-22.6). The median of the TRLNI of the OD:7.5 (2.6-17.7 s) and OS 6.7 (1.4-17.1 s). 36.6% of the patients presented fBUT < 10 s and 70.0% due to NIBUT. The Kendall correlation coefficient showed OD: tau-b: 0.2966 and OS: tau-b: 0.3065. The correlation of the OSDI score and tear break time was negative but not significant. Conclusions: NIBUT had shorter tear film rupture time compared to the fluorescein method. The correlation of OSDI questionnaire score was moderate for both methods.

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Objetivo: analizar la tendencia de las enfermedades que afectan la salud visual y su impacto económico para Colombia. Método: con la información de cinco instituciones nacionales que proporcionaron las bases de datos de la población atendida en los años 2011 y 2012; se construyó una única base de datos. Con la información ya compilada, se realizó un análisis retrospectivo que incluyó la caracterización de la población, frecuencia diagnóstica, tipo de procedimientos y costos. Los diagnósticos encontrados fueron agrupados según la clasificación CIE-10 para enfermedades del ojo. El total de los registros se comparó con los datos de los registros individuales de prestación de servició de salud, para estos mismos años, y se obtuvo un costo promedio de las enfermedades. Resultados: el total de la base analizada estaba conformada por 94.661 pacientes, atendidos en el año 2011 y 73.433 pacientes para el año 2012. Se encontró que el total de pacientes incluidos en este análisis corresponden al 8,2 % para el año 2011 y al 9,9 % del total de los registros individuales de prestación de servició de salud para el año 2012. La distribución de los principales diagnósticos encontrados en consulta externa para los dos años analizados, arrojó que los trastornos de refracción ocupan el primer lugar, seguidos de cataratas para ambos años. Conclusiones: se evidencia la necesidad de contar con investigaciones que muestren la situación de salud visual de la población con representatividad nacional, para poder generar planes, que promuevan el control, seguimiento y prevención de las enfermedades de salud visual en Colombia.

Objective: to analyze the trend of the diseases that aff ect the visual health and their economic impact on Colombian population. Methods: with the information from five national institutions that provided databases of people examined in 2011 and 2012 a database was built. With that unified information a retrospective analysis was done, that included the characterization of the population, diagnosis frequency, type and cost of the procedures. The diagnoses found were grouped according to the ICD-10 classification for eye diseases. The total number of registers was compared with data from the individual records of health service assistance for the same years, and an average cost per disease was obtained. Results: the total base analyzed consisted of 94 661 patients seen in 2011 and 73,433 patients in 2012. The patients included in this analysis correspond to 8.2% for 2011 and 9, 9% of total from the individual records of health service assistance for 2012. Distribution of the main outpatient diagnoses for the two years analyzed, showed that refractive disorders rank first followed by cataracts in both years. Conclusions: It is necessary to investigate the visual health state of a representative population in the country, in order to generate plans that promote the control, monitoring and prevention of eye diseases in Colombia.

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The molecules of N-(3-tert-butyl-1-phenyl-1H-pyrazol-5-yl)-2-chloro-N-(4-methoxybenzyl)acetamide, C(23)H(26)ClN(3)O(2), are linked into a chain of edge-fused centrosymmetric rings by a combination of one C-H...O hydrogen bond and one C-H...pi(arene) hydrogen bond. In N-(3-tert-butyl-1-phenyl-1H-pyrazol-5-yl)-2-chloro-N-(4-chlorobenzyl)acetamide, C(22)H(23)Cl(2)N(3)O, a combination of one C-H...O hydrogen bond and two C-H...pi(arene) hydrogen bonds, which utilize different aryl rings as the acceptors, link the molecules into sheets. The molecules of S-[N-(3-tert-butyl-1-phenyl-1H-pyrazol-5-yl)-N-(4-methylbenzyl)carbamoyl]methyl O-ethyl carbonodithioate, C(26)H(31)N(3)O(2)S(2), are also linked into sheets, now by a combination of two C-H...O hydrogen bonds, both of which utilize the amide O atom as the acceptor, and two C-H...pi(arene) hydrogen bonds, which utilize different aryl groups as the acceptors.

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Discute as disfunçöes sexuais, suas causas e os recursos disponíveis de tratamento, patologia e terapia sexual. Aborda, de forma clara e objetiva, o que se conhece a respeito das patologias sexuais, as contradiçöes existentes e a conduta apropriada a ser tomada pelo terapeuta sexual em cada caso em particular. (AM)

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