Search

A series of methyl esters of N-substituted (Z)- and (E)-maleamic acids were synthesized and their effect on food intake measured on fifth-instar nymphs of Triatoma infestans. Suppression of food intake was found only for the (Z)-isomers. The initial reaction rate of the synthesized compounds with glutathione (GSH) was calculated from the reaction in vitro of the (Z)-isomers. No reaction was observed with the (E)-isomers. Good correlation between the suppression of food intake, measured by its ED50 (effective dose that inhibited feeding of 50% of the population) and the initial reaction rate with GSH and the hydrophobic parameter pi, was found. [ABSTRACT FROM AUTHOR]

This study provides new data which suggest a novel interpretative hypothesis not only on the specific painting, but on the use of bloodletting as medical practice in the Florentine Quattrocento. As a part of a cycle of frescoes devoted to the Seven Corporal Works of Mercy, the examined lunette depicts the "Visit to the sick" in a domestic interior, but it has never been considered as an historical document of precise medical practices. The scene's definitive interpretation is still unresolved because of the uncertainty of some iconographic details. A campaign of in-situ and non-invasive technical investigations was performed to retrieve possible traces of previous details today concealed. The technical solutions adopted to implement the measurements campaign are illustrated, as an experimental example for remote sensing inspection of mural paintings in-situ. The position of the painting high up on a wall of an historical venue led to opting for stand-alone optical imaging techniques which could operate in remote sensing mode. By combining the use of portable Hyperspectral Imaging with Near Infrared photography a set of detailed images could be obtained that highlighted details not otherwise detectable. Focused on the objects held by the persons present, the analysis of the mural of Visit of the Buonomini in her Lying in Bed, the gift of swaddling cloth could be a tourniquet, shadows of folds of a blanket a thumb lancet, and an object held a blood collection bowl, supported the hypothesis that it could be a medieval bloodletting scene., (© 2024. The Author(s).)

Introduction: Bacteria of the genus Pseudomonas act as opportunistic pathogens. Pseudomonas putida has been considered a pathogen of low virulence and susceptible to multiple antibiotics, but in recent years resistant strains have emerged. The objective of this study is to describe the clinical characteristics, evolution and antibiotic resistance of P. putida bacteremia documented in pediatric hospitalized patients., Methods: Retrospective cases series. Pediatric patients admitted to the Prof. Dr. Juan P. Garrahan Hospital of Buenos Aires City, Argentina, with isolation in blood cultures of P. putida were included, between August 2015 and August 2020., Results: Sample consisting of 13 patients. Median age: 81 months (IQR 15-163). Ten of the patients were immunocompromised (77%), 11 (85%) had a central venous catheter, 2 (15%) received transfusions prior to the episode of bacteremia, and 6 (46%) had had an invasive procedure within the previous 30 days. Three patients (23%) presented bacteremia secondary to clinical focus and 10 (77%) had central venous catheter-associated bacteremia. All presented fever, 62% (8) evolved with sepsis and 15% (2) with septic shock. Two patients required admission to the intensive care unit (15%), and in 7 (54%) the central venous catheter was removed. None died. The median days of treatment was 14 (IQR 10-14). Resistance to carbapenems was 30%., Conclusion: All children had underlying comorbidities, most of them immunocompromised. Catheter-associated infection predominated. The sensitivity to antibiotics was variable. Given the emergence of multi-resistant strains, it is essential to know the local epidemiology., (Copyright © 2021 Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. Published by Elsevier España, S.L.U. All rights reserved.)

This work illustrates a novel prototype of a transmittance hyperspectral imaging (HSI) scanner, operating in the 400-900 nm range, and designed on purpose for non-invasive analysis of photographic materials, such as negatives, films and slides. The instrument provides high-quality spectral data and high-definition spectral images on targets of small size (e.g., 35 mm film strips) and is the first example of HSI instrumentation specifically designed for applications in the photographic conservation field. The instrument was tested in laboratory and on a set of specimens selected from a damaged photographic archive. This experimentation, though preliminary, demonstrated the soundness of a technical approach based on HSI for large-scale spectroscopic characterization of photographic archival materials. The obtained results encourage the continuation of experimentation of HSI as an advanced tool for photography conservation.

The identification of gemstones is an important topic in the field of cultural heritage, given their enormous value. Particularly, the most important precious stones, namely diamond, emerald, ruby and sapphire, are frequently subjected to counterfeit by substitution with objects of lesser value with similar appearance, colour or shape. While a gemmologist is able to recognise a counterfeit in most instances, more generally, it is not easy to do this without resorting to instrumental methods. In this work, the use of UV-visible diffuse reflectance spectrophotometry with optic fibres (FORS) is proposed as a fast and easy method for the preliminary identification of gemstones, alternative to the classical methods used by gemmologists or to Raman spectroscopy, which is by far the instrumental method with the best diagnostic potential, but it cannot be used in situations of problematic geometric hindrance. The possibilities and the limitations given by the FORS technique are critically discussed together with the spectral features of the most important gemstones. Finally, the application of chemometric pattern recognition methods is described for the treatment of large sets of spectral data deriving from gemstones identification.

Sporotrichosis is a subacute-chronic fungal infection caused by dimorphic fungi of the Sporothrix schenckii Complex. It is more common in tropical areas. The prevalence in Argentina is estimated between 0.01 and 0.02%. In half of the patients it manifests as lymphocutaneous sporotrichosis, which occurs after inoculation of the fungus into the skin after minor trauma. The initial lesion is a papule or nodule that occurs with the appearance of an ascending chain of mobile, painless and erythematous subcutaneous nodules. The diagnosis is made from mycological culture. The antifungal of choice is itraconazole and the prognosis is usually favorable. We present the case of a healthy 4-year-old girl who consulted for subacute axillary lymphadenopathy without response to multiple antimicrobial regimens, arriving at the diagnosis of lymphocutaneous sporotrichosis from the culture of a lymph node biopsy sample.

Scientific investigations of artworks are crucial in terms of preservation since they provide a measurable evaluation of the materials and the state of conservation. This is the case of Antonello da Messina's painting "Ecce Homo": its delicate state of conservation, with the need for constant monitoring, required a broad and in-depth diagnostic campaign to support the restorers. The project was carried out entirely in situ using non-invasive cutting-edge techniques and proposes a multimodal and data-centric approach, integrating 3D and 2D methodologies. The surface irregularities and the support were analysed with a structured-light 3D scanner and X-ray tomography. The painting materials were investigated with X-ray fluorescence scanning (MA-XRF) and reflectance hyperspectral imaging (HSI). Primarily, the data were jointly used for a scientific scope and provided new knowledge of the painting in terms of materials and painting techniques. In addition, two web-based interactive platforms were developed: one to provide restorers and experts with a new perspective of the hidden geometries of the painting, and the other targeted at the general public for dissemination purposes. The results of the Ecce Homo scientific analysis were exhibited, using a touch-screen interface, and developed for different user levels, from adults to kids., (© 2021. The Author(s).)

Background: The knowledge of the clinical and evolutionary characteristics of children with SARS-CoV-2 is continuously updated. The true impact of the disease in the pediatric population is still unknown., Aim: To describe the clinical characteristics, the use of resources and the evolution of children with COVID-19 in the Garrahan Pediatric Hospital, Buenos Aires, Argentina, in the first 20 weeks from the identification of the first case., Methods: Descriptive, analytical, retrospective study. The epidemiological, clinical, evolutionary characteristics and the use of hospital resources of patients < 18 years with confirmed COVID-19 are described. In addition, these characteristics were compared according to whether they occurred in the first 10 epidemiological weeks from the first case of COVID-19 in the hospital or in the following ten weeks., Results: n: 280. The median age was 83 months (IQR 33-144). 209 patients (74.6%) were hospitalized. The median days of hospitalization was 8 days (IQR 3-13). According to the WHO severity classification, there were 184 mild cases (65.7%), 3 moderate (1.1%), 16 severe (5.7%) and 20 critical patients (7.1%). The main reasons for admission to the ICU were not related to SARS-CoV-2 infection. When comparing the characteristics of the patients in the two periods, in the first period there was a higher frequency of underlying comorbidities, immunosuppressive treatment, the consultation was later and the patients had more requirements for ICU admission. Two children (0.7%) died in relation to the infection, both with severe comorbidities and severe bacterial coinfections., Conclusion: In this study, patients with underlying disease predominated. The mild form of the disease was the most frequent presentation. At the beginning of the pandemic, there were more patients under immunosuppressive treatment, the consultation was later and the hospitalization was more frequent, prolonged and with more serious clinical pictures.

Objective: To evaluate the differential characteristics of SARS-COV-2 associated inflammatory multisystem syndrome (MIS-C) in children., Methods: A retrospective cohort study was conducted.  The definition of MIS- C was based on WHO criteria. Temporally related COVID-19 patients were included as controls., Results: 25 patients with MIS-C and 75 controls were included. Multivariate multiple logistic regression model of variables that showed to be significant in univariate analysis revealed that age ≥2 years (OR 24.7; 95% CI 1.03 -592.4; P=0.048), lymphopenia (OR 9.03, 95%CI 2.05-39.7; P=0.004), and platelet count <150x109/L (OR 11.7; 95% CI 1.88-75.22; P=0.009) were significantly associated with MIS-C. Presence of underlying disease seemed to reduce the risk of MIS-C (OR 0.06; 95% CI 0.01-0.3)., Conclusions: MIS-C was more common in patients older than 2 years and in those with lymphopenia or thrombocytopenia. Underlying disease appears to reduce the risk of MIS-C.

Plastics have been increasingly used to create modern and contemporary art and design, and nowadays, museum collections hold numerous objects completely or partially made of plastics. However, the preservation of these materials is still a challenging task in heritage conservation, especially because some plastics show signs of degradation shortly after their production. In addition, different degradation mechanisms can often take place depending on the plastic composition and appropriate environmental and packaging conditions should be adopted. Therefore, methods for in situ and rapid characterization of plastic artifacts' composition are greatly needed to outline proper conservation strategies. Infrared (IR) spectroscopy, such as attenuated total reflection Fourier transform infrared spectroscopy (ATR FT-IR), is a well-established method for polymeric material analysis. However, ATR FT-IR requires an intimate contact with the object, which makes its application less appropriate for the in situ investigation of fragile or brittle degraded plastic objects. Mid-FT-IR reflectance spectroscopy may represent a valid alternative as it allows in situ measurements with minimum or even no contact, and IR data can be acquired rapidly. On the other hand, spectral interpretation of reflectance spectra is usually difficult as IR bands may appear distorted with significant changes in band maximum, shape, and relative intensity, depending on the optical properties and surface texture of the material analyzed. Presently, mid-FT-IR reflection devices working in external reflection (ER FT-IR) and diffuse reflection infrared Fourier transform spectroscopy (DRIFTS) modes have been used in cultural heritage research studies. As the collected vibrational information depends on the optical layout of the measuring system, differences between ER FT-IR and DRIFT spectra are thus expected when the same polymer is analyzed. So far, ER FT-IR and DRIFT spectroscopy have been individually explored for the identification of plastic objects, but comparative studies between the application of two reflectance FT-IR modes have not been presented yet. In this work, the use of two portable FT-IR spectrometers equipped with ER FT-IR and DRIFTS modes were compared for plastics identification purposes for the first time. Both references of polymeric materials and historical plastic objects (from a Portuguese private collection) were studied and the differences between ER FT-IR and DRIFT spectra were discussed. The spectra features were examined considering the two different optical geometries and analytes' properties. This new insight can support a better understanding of both vibrational information acquired and practical aspects in the application of the ER FT-IR and DRIFTS in plastic analysis.

Body and head lice are known to be exclusive ectoparasites of human hosts. Current genomic and transcriptomic data suggest that both louse types represent ecotypes of the same species. They exhibit morphological and physiological differences that probably arose from living in different biotopes. Sensory traits represent suitable candidates to be affected by environmental heterogeneity. Therefore, through scanning electron microscope studies, this study analysed and compared the sensory structures of both ecotypes' antennae. Seven types of sensory structures were identified in both ecotypes: bristles, tuft organs, pore organs, single pore and three morphotypes of sensilla basiconica. Notably, the single pore and the morphotypes of sensilla basiconica were described for the first time in the body louse antenna. This study's comparative analysis mainly revealed size differences across the sensory structures of the ecotypes. Bristles of the flagellomere 2 of the body louse antenna were longer than the head louse bristles. In addition, the pore organs of the head louse antenna presented a higher diameter than those of the body louse. The possible relevance of size differences regarding the biotopes exploited by the body louse and the head louse is discussed. Yet, physiological studies may help to fully understand the phenotypical differences of both ecotypes., (© 2020 The Royal Entomological Society.)

RGB digital cameras (RGB) compress the spectral information into a trichromatic system capable of approximately representing the actual colors of objects. Although RGB digital cameras follow the same compression philosophy as the human eye (OBS), the spectral sensitivity is different. To what extent they provide the same chromatic experiences is still an open question, especially with complex images. We addressed this question by comparing the actual colors derived from spectral imaging with those obtained with RGB cameras. The data from hyperspectral imaging of 50 natural scenes and 89 paintings was used to estimate the chromatic differences between OBS and RGB. The corresponding color errors were estimated and analyzed in the color spaces CIELAB (using the color difference formulas Δ E * ab and CIEDE2000), J z a z b z , and iCAM06. In CIELAB the most frequent error (using Δ E * ab ) found was 5 for both paintings and natural scenes, a similarity that held for the other spaces tested. In addition, the distribution of errors across the color space shows that the errors are small in the achromatic region and increase with saturation. Overall, the results indicate that the chromatic errors estimated are close to the acceptance error and therefore RGB digital cameras are able to produce quite realistic colors of complex scenarios.

This paper focuses on the application of non-invasive techniques to study a peculiar object, an alchemical codex completely made of lead stored at the State Archive of Florence. 1 The sheets of the codex appeared entirely covered by thick and heterogeneous corrosion patinas for which a restoration was planned for their removal. This activity was supported by analytical investigations to characterise the materials that made up the patinas using non-invasive techniques. The codex pages were initially documented with imaging techniques. Subsequently, spectroscopic data were acquired on each sheet using spot analytical techniques: Total Reflectance Fourier Transform Infrared Spectroscopy (TR FT-IR), Fibre Optics Reflectance Spectroscopy (FORS), X-Ray Fluorescence (XRF), Scanning Electron Microscopy (SEM) and X-Ray Diffraction (XRD). The identification of deterioration compounds has been extremely useful for the conservator to deal with the removal of dangerous and disfiguring patinas., Competing Interests: Declaration of competing interest The authors declare that they have no known competing/financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)