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1.
J Proteomics ; 249: 104370, 2021 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-34517122

RESUMO

It is well established that the ink pigment used for writing the Dead Sea Scrolls (DSS) is mainly composed of carbon soot. The ink's binder however has yet to be securely identified. By applying EVA (ethylene vinyl acetate containing strong anion and cation exchangers admixed with C8 and C18) diskettes on one fragment and analyzing the captured material, the following study was able to determine the composition of the binder. Proteins admixed of plant proteins (ribulose biphosphate carboxylase, rhamnogalacturonate lyase, α-galactosidase A, calmodulin, among those identified) as well as of a few glycoproteins with different combinations of pentosyl and hexosyl units with plant acids (stearic, palmitic, oleic, linoleic and linolenic acids) and terpenes (triacontanol, catechin, lupeol) are mixed attributes of acacia trees which suggests the use of gum Arabic as the ink's binder. SIGNIFICANCE: Whereas a huge body of reports has explored any possible aspect of the Dead Sea Scrolls, including the dating and the animal origin of the parchment, one aspect had not been investigated so far, namely which kind of ligand had been adopted to ensure a firm binding of the ink (in reality carbon soot) to the supporting parchment. In the present investigation it has been demonstrated that this "glue" is a mixture of plant proteins, as well as a few glycoproteins, together with plant acids and terpenes. These proteins and metabolites belong to two species of trees, Vachellia nilotica and Acacia Albida, widespread in this Middle East region. The EVA methodology here adopted has shown that it is possible to explore any item pertaining to the world Cultural Heritage in the absence of damage or contamination thus permititng to analyze any possible precious document stored in museum, public libraries and private collections.


Assuntos
Tinta , Proteômica , Animais , Metabolômica
2.
Electrophoresis ; 41(21-22): 1931-1940, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32459049

RESUMO

George Orwell, fighter for the Republican Army during the Spanish Civil War, was shot through the throat by a sniper on 20th May 1937 and nearly killed. After receiving only a summary external treatment, on the 29th, he was cured in a Barcelona hospital where he was infected by the Koch bacillus. After fleeing from Spain on 23rd June 1937, he repaired to his cottage in Wallington, Hertfordshire, wherefrom he wrote a letter to Sergey Dynamov, Editor of Soviet journal "Foreign Literature." This typewritten letter was analyzed by application of five EVA strips (ethylene vinyl acetate studded with strong cation and anion and with C8 and C18 resins; four on the corners and one over his signature), searching for biological traces. Upon elution of the captured biologicals, trypsin digestion and Orbitrap Fusion trihybrid mass spectrometer analyses, three of the five strips yielded clear traces of six unique proteins (via proteotypic peptides) of the tuberculosis bacterium. Additionally, MALDI TOF analysis of saliva of a tuberculosis patient and the EVA strip eluates gave a spectrum of 14 peptide bands (Mr 2700 to 6700 Da range) coincident between the two samples, thus, fully confirming Orwell's pathology. These results are attributed to saliva traces on Orwell's fingertips and to the fact that the letter was written on 2nd July 1937, when Orwell's pathology was at its peak.


Assuntos
Proteínas de Bactérias , Correspondência como Assunto/história , Mycobacterium tuberculosis/química , Proteômica/métodos , Tuberculose , Conflitos Armados/história , Proteínas de Bactérias/análise , Proteínas de Bactérias/química , Proteínas de Bactérias/isolamento & purificação , História do Século XX , Humanos , Literatura , Masculino , Saliva/microbiologia , Extração em Fase Sólida , Espanha , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Tuberculose/diagnóstico , Tuberculose/história , Tuberculose/microbiologia
3.
Electrophoresis ; 40(23-24): 3050-3056, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-30963594

RESUMO

The original manuscript of Casanova's Memoirs is stored at the Bibliothèque Nationale de France in Paris. We have gained access to it and explored the surfaces of chapters one and two (via the ethylene vinyl acetate [EVA] film technology, i.e., of diskettes of ethylene vinyl acetate with embedded strong cation and anion exchangers and C8 resins) in search of potential diseases of the author, especially of the gonorrhea bacterium, since Casanova reported that he had several bouts of this pathology along his adventurous life. Although the bacterium was not found, we have detected high levels of HgS as red spots along the lines of the manuscript, suggesting that Casanova was using this chemical as a cure for his venereal disease. Additionally, among the several bacteria identified on the surface via mass spectrometry, we could detect traces of Streptococcus uberis, a typical animal infection, found also in humans, together with a few strains of Lactobacilli, probably present in his saliva. The EVA film technology appears to open new horizons for investigating the world Cultural Heritage.


Assuntos
Livros/história , Tipagem Molecular/métodos , Redação/história , Proteínas de Bactérias/análise , Proteínas de Bactérias/química , Proteínas de Bactérias/classificação , França , História do Século XVIII , Humanos , Lactobacillus/química , Espectrometria de Massas/métodos , Compostos de Mercúrio/análise , Compostos de Mercúrio/química , Polivinil , Streptococcus/química
4.
Electrophoresis ; 39(18): 2344-2350, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29607521

RESUMO

A noninvasive mini-sensor for blood glucose concentration assessment has been developed. The monitoring is performed by gently pressing a wrist or fingertip onto the chemochromic mixture coating a thin glass or polymer film positioned on the back panel of a smart watch with PPG/HRM (photoplethysmographic/heart rate monitoring sensor). The various chemochromic components measure the absolute values of the following metabolites present in the sweat: acetone, acetone beta-hydroxybutirate, aceto acetate, water, carbon dioxide, lactate anion, pyruvic acid, Na and K salts. Taken together, all these parameters give information about blood glucose concentration, calculated via multivariate analysis based on neural network algorithms built into the sensor. The Clarke Error Grid shows an excellent correlation between data measured by the standard invasive glucose analyser and the present noninvasive sensor, with all points aligned along a 45-degree diagonal and contained almost exclusively in sector A. Graphs measuring glucose levels five times a day (prior, during and after breakfast and prior, during and after lunch), for different individuals (males and females) show a good correlation between the two curves of conventional, invasive meters vs. the noninvasive sensor, with an error of ±15%. This novel, noninvasive sensor for indirect glucometry is fully miniaturized, easy to use and operate and could represent a valid alternative in clinical settings and for individual, personal users, to current, invasive tools.


Assuntos
Automonitorização da Glicemia/instrumentação , Dispositivos Eletrônicos Vestíveis , Adulto , Algoritmos , Técnicas Biossensoriais/instrumentação , Glicemia/análise , Calorimetria/instrumentação , Feminino , Vidro/química , Humanos , Masculino , Membranas Artificiais , Polímeros/química , Propriedades de Superfície
5.
Electrophoresis ; 38(17): 2168-2174, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28556952

RESUMO

A miniaturized chemical sensor is here described for the analysis of environmental pollutants (VOC: volatile organic chemicals). It is used for remote detection of formaldehyde (FA) fumes in the atmosphere, and is based on the redox reaction between FA and silver nitrate. The sensor is worn as a bracelet and the data acquired are transferred via a Bluetooth channel to a smartphone. A dedicated software transforms the signal from a grey to a color scale. The signal response has been assessed over low (20 to 120 ppb) as well as higher (1-15 ppm range) levels. The sensor has been applied to monitor potential FA fumes of some artwork in the Summer Palace in Beijing and the modifications induced by FA treatment on a precious Stradivarius violin. The performance of this novel sensor is compared with a commercial apparatus widely adopted, namely the Honeywell MultiRAE Lite wireless portable multi-gas monitor (pumped model).


Assuntos
Monitoramento Ambiental/instrumentação , Monitoramento Ambiental/métodos , Formaldeído/análise , Miniaturização/instrumentação , Smartphone , Sensibilidade e Especificidade , Compostos Orgânicos Voláteis/análise
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