A minimal-complexity light-sheet microscope maps network activity in 3D neuronal systems.

In vitro systems mimicking brain regions, brain organoids, are revolutionizing the neuroscience field. However, characterization of their electrical activity has remained a challenge as it requires readout at millisecond timescale in 3D at single-neuron resolution. While custom-built microscopes used with genetically encoded sensors are now opening this door, a full 3D characterization of organoid neural activity has not been performed yet, limited by the combined complexity of the optical and the biological system. Here, we introduce an accessible minimalistic light-sheet microscope to the neuroscience community. Designed as an add-on to a standard inverted microscope it can be assembled within one day. In contrast to existing simplistic setups, our platform is suited to record volumetric calcium traces. We successfully extracted 4D calcium traces at high temporal resolution by using a lightweight piezo stage to allow for 5 Hz volumetric scanning combined with a processing pipeline for true 3D neuronal trace segmentation. As a proof of principle, we created a 3D connectivity map of a stem cell derived neuron spheroid by imaging its activity. Our fast, low complexity setup empowers researchers to study the formation of neuronal networks in vitro for fundamental and neurodegeneration research.

What are the real environmental impacts of Antarctic tourism? Unveiling their importance through a comprehensive meta-analysis.

Human activities in Antarctica were increasing before the COVID-19 pandemic, and tourism was not an exception. The growth and diversification of Antarctic tourism over the last few decades have been extensively studied. However, environmental impacts associated with this activity have received less attention despite an increasing body of scholarship examining environmental issues related to Antarctic tourism. Aside from raising important research questions, the potential negative effects of tourist visits in Antarctica are also an issue discussed by Antarctic Treaty Consultative Parties. This study presents the results of a meta-analysis of scholarly publications that synthesizes and updates our current knowledge of environmental impacts resulting from Antarctic tourism. A first publication database containing 233 records that focussed on this topic was compiled and subjected to a general bibliometric and content analysis. Further, an in-depth content analysis was performed on a subset of 75 records, which were focussed on showing specific research on Antarctic tourism impacts. The main topic, methods, management proposals, and research gaps highlighted by the respective authors of these 75 publications were assessed. The range of research topics addressed, the methods used - including the application of established research designs from the field of environmental impact assessment -, and the conclusions reached by the study authors are discussed. Interestingly, almost one third of the studies did not detect a direct relationship between tourism and significant negative effects on the environment. Cumulative impacts of tourism have received little attention, and long-term and comprehensive monitoring programs have been discussed only rarely, leading us to assume that such long-term programs are scarce. More importantly, connections between research and policy or management do not always exist. This analysis highlights the need for a comprehensive strategy to investigate and monitor the environmental impacts of tourism in Antarctica. A first specific research and monitoring programme to stimulate a debate among members of the Antarctic scientific and policy communities is proposed, with the ultimate goal of advancing the regulation and management of Antarctic tourism collaboratively.

Search for Lepton Number and Flavor Violation in K

Searches for the lepton number violating K^{+}→π^{-}µ^{+}e^{+} decay and the lepton flavor violating K^{+}→π^{+}µ^{-}e^{+} and π^{0}→µ^{-}e^{+} decays are reported using data collected by the NA62 experiment at CERN in 2017-2018. No evidence for these decays is found and upper limits of the branching ratios are obtained at 90% confidence level: B(K^{+}→π^{-}µ^{+}e^{+})<4.2×10^{-11}, B(K^{+}→π^{+}µ^{-}e^{+})<6.6×10^{-11} and B(π^{0}→µ^{-}e^{+})<3.2×10^{-10}. These results improve by 1 order of magnitude over previous results for these decay modes.

Chemical composition and antioxidant activity of the volatile fraction extracted from air-dried fruits of Tunisian Eryngium maritimum L. ecotypes.

BACKGROUND: Eryngium maritimum L., also known as 'sea holly', is a typical dune plant species belonging to the Apiaceae family and commonly used in Tunisia for therapeutic purposes in folk medicine. In the present study, the chemical composition and antioxidant activity of the volatile fraction extracted from air-dried fruits of five Tunisian E. maritimum ecotypes were determined. RESULTS: The total volatile amount ranged from 0.31% to 0.93% (w d.w.-1 ). Sixty-six volatile components were identified by means of GC-MS and accounted for 77.05-86.65% of the total extracted volatile oil. The majority of the identified metabolites were hydrocarbon sesquiterpenes and oxygenated sesquiterpenes, amounting on average to 46.69% and 30.01% of total volatiles, respectively. The principal individual components were germacrene D (13.62-31.71%), 15-hydroxy-α-muurolene (12.04-18.58%), and germacrene B (6.77-15.04%). Significant differences were noticed among E. maritimum populations. The volatile profile of E. maritimum fruits was consistently different from those of the aerial parts and roots of plants of the same species reported in previous investigations. Average radical scavenging capacity of the volatile fraction, as determined by DPPH and ABTS tests, was twice higher than that of the Trolox control. CONCLUSION: This study characterised for the first time the fruits of E. maritimum for the composition and radical-scavenging capacity of their volatile fraction. The growth location confirmed as a pivotal factor in influencing the volatile profile of the fruits. © 2017 Society of Chemical Industry.

Identification and quantification of phenolic compounds in edible wild leafy vegetables by UHPLC/Orbitrap-MS.

BACKGROUND: A recent interest in edible wild leafy vegetables has been documented. Consumers often associate these species with health promotion. In this study, several wild species of the Asteraceae family and Knautia integrifolia (Dipsacaceae) were locally documented for their use in traditional cuisine and sampled from the wild. RESULTS: Phenolic compounds were identified and quantified by ultra-high-performance liquid chromatography coupled to Orbitrap high-resolution mass spectrometry. Hydroxycinnamic acids ranging from 1388 to 53 076 mg kg-1 dry weight (DW) were the most abundant compounds in all species (69-98% of the total phenolic content) except Tragopogon pratensis. Thirty compounds were identified as flavonoids, mostly as glycosidic forms of luteolin, apigenin, kaempferol and quercetin. The sum of flavonoids ranged between 212 and 12 598 mg kg-1 DW; they represented 65% of the total phenolic content for T. pratensis. Three anthocyanins were detected, representing in most cases less than 1% of the total phenolic content (3-627 mg kg-1 DW). Higher anthocyanin contents were observed for Cichorium types. CONCLUSION: Different phenolic profiles were observed between species, especially considering the class of flavonoids. Individual species may be of some interest for their content of specific minor flavonoids. © 2017 Society of Chemical Industry.

The impact of sesquiterpene lactones and phenolics on sensory attributes: An investigation of a curly endive and escarole germplasm collection.

In the present study, curly endive (Cichorium endivia L. var. crispum) and escarole (Cichorium endivia L. var. latifolium) accessions were investigated for their sensory characters (bitterness, astringency and herbaceous flavour) and acceptance in relation to sesquiterpene lactone and phenolic content. Different facets of the perception of these sensory traits in relation to lactones and phenolics were brought out. Lactucopicrin and kaempferol malonyl glucoside were consistently related to bitterness, astringency and herbaceous flavour perceptions. Overall acceptance was significantly and inversely related mainly to bitterness. The generic statement that sesquiterpene lactones and phenolic compounds are determinants of bitterness and other related sensory characters does not seem to be fully consistent with our data, that indicated how the balance of different compounds affects these traits individually, in a rather complex manner, with a prevailing negative impact of phenolics. Bitter, astringent, and herbaceous perceptions were significantly affected by variety, with curly endive showing on average higher scores in comparison to escarole, with particular respect to bitterness.

Effect of epidural analgesia on operative vaginal birth rate.

The aim of the study was to investigate if epidural analgesia may affect the operative vaginal birth rate. An observational study was carried out on 1,158 in low-risk patients who delivered vaginally; 46.9% of these patients underwent epidural analgesia using different doses and drugs. Overall, epidural analgesia enhanced the probability of vacuum delivery (OR 2.70 95% CI 1.88-3.89, p < 0.001). Vacuum application was increased about seven times by administration of fentanyl alone at the first dose, while it was reduced if ropivacaine was added to fentanyl. In patients undergoing epidural analgesia, increasing the amount of ropivacaine at the first dose reduced the probability of vacuum delivery (OR 0.82; 95% CI 0.67-1.00, p = 0.05). Moreover, increasing the number of top-ups reduced the probability of vacuum delivery (OR 0.49 95% CI 0.27-0.93, p = 0.029) and the time of the second stage of labor. On the other hand, increasing time from the first dose of epidural to the last top-up increased the risk of operative vaginal delivery (OR 1.33 95% CI 1.03-1.72, p = 0.031) and the time of the second stage of labor. Epidural analgesia seems to favor spontaneous delivery when it is properly carried on.

Diagnóstico por imágenes en pacientes pediátricos con carcinoma diferenciado tiroideo / Imaging diagnosis in pediatric patients with differentiated thyroid carcinoma

En 25 pacienes con Cáncer Diferenciado de tiroides (CDT) atendidos en nuestro hospital entre 1990 y 2005, analizamos retrospectivamente los signos clínicos, antecedentes personales y familiares, exámenes por imágenes e histopatología, con el objetivo de evaluar la utilidad del diagnóstico por imágenes. El 72 por ciento fueron mujeres y 28 por ciento varones. La edad promedio al diagnóstico fue de 10 años, rango: 4 años y 9 meses a 16 años. Presentaron antecedentes familiares de patología tiroidea el 26 por ciento. El motivo de consulta más frecuente fue la aparición de adenopatías en cuello, solo en un 10%, sólo en un 10 por ciento de los pacientes fue nódulo tiroideo, sin embargo 20 de ellos presentaron tumoración cervical asociada a ganglios regionales.. Tres pacientes fueron derivados con diagnóstico de cáncer por biopsia de un ganglio cervical. La ultrasonografía (US) mostró en 33% compromiso difuso bilateral y 67 por ciento unilateral, predominando el patrón nodular heterogéneo, hiperecogénico, contorno irregular y calcificaciones. Asimismo se realizó Eco Doppler en 11/25 pacientes, que mostraron flujo intranodular con vasos tortuosos y distribución anárquica. El 64 por ciento tenía adenomegalias regionales. El 32 por ciento presentaba metástasis pulmonares al diagnóstico confirmadas por Tomografía Computada (TC). Todos los pacientes con CDT presentaron la forma papilifera. Cuatro pacientes desarrollaron cáncer medular de tiroides derivado de las células parafoliculares: 2 pacientes correspondieron a la forma familiar MEN 2A, 1 fue MEN 2B y la cuarta paciente presentó un Ca medular esporádico. En todos los casos el tratamiento fue la tiroidectomía total y extirpación de los ganglios regionales seguidas por dosis terapéuticas de I 131. La US es el método más utilizado y de enorme valor para el diagnóstico de la patología nodular tiroidea siendo el método complementario de elección al examen físico.

Hallazgos ultrasonográficos en hipertensión portal secundaria a transformación cavernomatosa de la vena porta en pediatría / Ultrasonographic findings in portal hypertension caused by cavernomatous transformation of the portal vein in children

Propósito: reseñar los hallazgos clínicos y ecográficos obtenidos durante 16 años del estudio de 159 pacientes, en quienes se diagnosticó transformación cavernomatosa de la vena porta (TCVP) e hipertensión portal (HP). Material y Métodos: Evaluamos los registros de 159 pacientes a los que se les diagnosticó TCVP durante el período 1987 -2003, consignando los datos referidos al cuadro clínico de presentación, patologías asociadas, los signos ultrasonográficos (US) morfológicos hallados al diagnóstico, su prevalencia y las relaciones entre las diferentes variables. Resultados: Los hallazgos clínicos más significativos fueron sangrado gastrointestinal y esplenomegalia. La imagen US, se caracteriza por múltiples estructuras anecoicas tortuosas, que reemplazan la imagen ecográfica caracteristica de la vena porta, ella permite realizar el diagnóstico inmediato y preciso de TCVP. Los principales signos US de HP hallados fueron: esplenomegalia (71,6 por ciento el bazo fue de tamaño normal en el 28,3 por ciento) y relación epiplon menor /aorta aumentada (69 ,1 por ciento). Circulación colateral: vena coronaria en epiplon menor (44 por ciento), venas colaterales dorsales (28.9 por ciento), várices vasiculares (36,8 por ciento), várices hemorroidales ( 8.8 por ciento). Ascitis (9.4 por ciento). El tamaño hepático se observó disminuido en el 32.6 por ciento de los pacientes. Conclusión: la TCVP y la HP secundaria a la misma, en la actualidad, son entidades que pueden ser diagnosticadas mediante la exploración US morfológica. La utilización de otros métodos de imágenes de mayor complejidad, en los pacientes pediátricos, debe estar supeditada a la necesidad de información complementaria relacionada con la toma de decisiones quirúrgicas

Sindrome linfoproliferativo postransplante renal: evaluación por imágenes / Post transplant lymphoproliferative disease alter renal transplantation: imaging evaluation

El sindrome linfoproliferativo post transplante (SLPT) se presenta en pacientes transplantados en quienes la inmunosupresión crónica induce una proliferación linfoidea maligna monoclonal indistinguible del linfoma No Hodgkin. El éxito de los transplantes de órganos se incremento a partir de las nuevas terapias inmunosupresoras, los avances en las técnicas quirúrgicas, y los cuidados postoperatorios. Sin embargo pueden aparecer complicaciones como las infecciones oportunistas, enfermedades malignas secundarias, el SLPT y el rechazo, que reflejan la alteración del balance inmunológico del receptor. Propósito: Describir la incidencia, distribución y hallazgos por imágenes en el SLPT post transplante renal en una población de pacientes pediátricos. Población y Métodos: Se evaluaron los registros de los pacientes con transplante renal realizados entre diciembre 1988 y junio 2001. Se consignaron: clínica al diagnóstico del SLPT; tiempo postransplante; esquema inmunosupresor recibido, hallazgos por imágenes en radiología, ultrasonografía (US), tomografía computada (TC) y/o resonancia magnética (RM), variedad histológica, tratamiento y evolución: Resultados: En el período evaluado se realizaron 346 transplantes en 328 pacientes. Nueve de ellos presentaron SLPT (2.7%). En todos los casos la sospecha clínica fue confirmada por imágenes. El tratamiento incluyó reducción de la inmunosupresión. Los estudios por imágenes constituyen un elemento diagnóstico significativo en la evaluación de los pacientes con transplante tanto en el seguimiento programado como ante la sospecha clínica de SLPT.

X-ray photoelectron spectra of Pd(II) and Pt(II) complexes with 1,3-thiazolidine-2-thione. A quantum mechanics study on the free ligand.

Metal complexes of general formula M(ttz)2X2 (with M= Pd(II) or Pt(II); X = Cl or Br; ttz = 1,3-thiazolidine-2-thione) have been synthetized as crystalline compounds and studied by means of X-ray Photoelectron Spectroscopy (XPS). The chemical shift of core level signals showed that ttz is bonded to the metal through the thioketonic sulphur atom and that electronic charge redistribution in the ligand takes place after complexation. No metal-nitrogen bonds are present. This is consistent with the results of all the quantum mechanical models according to which hydrogen is bound to nitrogen, even in the hydrogen bonded complex, making the latter rather unavailable to coordination

Metodología diagnóstica en la obstrucción intestinal del recién nacido / Diagnostic radiology of neonatal intestinal obstruction

La obstrucción intestinal (OI) es la emergencia quirúrgica más frecuente en el recién nacido. Entre abril de 1988 y marzo de 1999 fueron estudiados 235 pacientes que presentaron OI. La radiografía simple de abdomen en dos proyecciones (decúbito dorsal, de pie, capo volta o invertograma) fue diagnóstica en todos los casos. Hallazgos: OI alta: atresia duodenal (n=28), malrotación (n=33). OI baja: malformación anorrectal (con atresia anal) (n=64), atresia yeyunal/ileal (n=49), enfermedad de Hischsprung (n=39), íleo meconial (n=22). La radiografía simple de abdomen permite una evaluación adecuada del paciente en la misma sala de Neonatología. Reemplaza a la seriada esofagogastroduodenal en el estudio de la obstrucción intestinal del recién nacido, utilizando el aire como contraste y evitando además los riesgos de aspiración por vómitos y disminuyendo la exposición a las radiaciones (AU)

Metodología diagnóstica en la obstrucción intestinal del recién nacido / Diagnostic radiology of neonatal intestinal obstruction

La obstrucción intestinal (OI) es la emergencia quirúrgica más frecuente en el recién nacido. Entre abril de 1988 y marzo de 1999 fueron estudiados 235 pacientes que presentaron OI. La radiografía simple de abdomen en dos proyecciones (decúbito dorsal, de pie, capo volta o invertograma) fue diagnóstica en todos los casos. Hallazgos: OI alta: atresia duodenal (n=28), malrotación (n=33). OI baja: malformación anorrectal (con atresia anal) (n=64), atresia yeyunal/ileal (n=49), enfermedad de Hischsprung (n=39), íleo meconial (n=22). La radiografía simple de abdomen permite una evaluación adecuada del paciente en la misma sala de Neonatología. Reemplaza a la seriada esofagogastroduodenal en el estudio de la obstrucción intestinal del recién nacido, utilizando el aire como contraste y evitando además los riesgos de aspiración por vómitos y disminuyendo la exposición a las radiaciones