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1.
Mol Cell ; 79(3): 406-415.e7, 2020 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-32692975

RESUMO

Protein secretion in eukaryotes and prokaryotes involves a universally conserved protein translocation channel formed by the Sec61 complex. Unrelated small-molecule natural products and synthetic compounds inhibit Sec61 with differential effects for different substrates or for Sec61 from different organisms, making this a promising target for therapeutic intervention. To understand the mode of inhibition and provide insight into the molecular mechanism of this dynamic translocon, we determined the structure of mammalian Sec61 inhibited by the Mycobacterium ulcerans exotoxin mycolactone via electron cryo-microscopy. Unexpectedly, the conformation of inhibited Sec61 is optimal for substrate engagement, with mycolactone wedging open the cytosolic side of the lateral gate. The inability of mycolactone-inhibited Sec61 to effectively transport substrate proteins implies that signal peptides and transmembrane domains pass through the site occupied by mycolactone. This provides a foundation for understanding the molecular mechanism of Sec61 inhibitors and reveals novel features of translocon function and dynamics.


Assuntos
Macrolídeos/farmacologia , Microssomos/química , Ribossomos/química , Canais de Translocação SEC/química , Animais , Sítios de Ligação , Sistema Livre de Células/metabolismo , Cães , Expressão Gênica , Células HCT116 , Células HEK293 , Humanos , Macrolídeos/química , Macrolídeos/isolamento & purificação , Microssomos/metabolismo , Simulação de Dinâmica Molecular , Mutação , Mycobacterium ulcerans/química , Mycobacterium ulcerans/patogenicidade , Pâncreas/química , Pâncreas/metabolismo , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Domínios e Motivos de Interação entre Proteínas , Transporte Proteico , Ribossomos/metabolismo , Canais de Translocação SEC/antagonistas & inibidores , Canais de Translocação SEC/genética , Canais de Translocação SEC/metabolismo , Homologia Estrutural de Proteína , Especificidade por Substrato
2.
Mol Syst Biol ; 19(3): e11099, 2023 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-36705093

RESUMO

Metabolic flux is the final output of cellular regulation and has been extensively studied for carbon but much less is known about nitrogen, which is another important building block for living organisms. For the tuberculosis pathogen, this is particularly important in informing the development of effective drugs targeting the pathogen's metabolism. Here we performed 13 C15 N dual isotopic labeling of Mycobacterium bovis BCG steady state cultures, quantified intracellular carbon and nitrogen fluxes and inferred reaction bidirectionalities. This was achieved by model scope extension and refinement, implemented in a multi-atom transition model, within the statistical framework of Bayesian model averaging (BMA). Using BMA-based 13 C15 N-metabolic flux analysis, we jointly resolve carbon and nitrogen fluxes quantitatively. We provide the first nitrogen flux distributions for amino acid and nucleotide biosynthesis in mycobacteria and establish glutamate as the central node for nitrogen metabolism. We improved resolution of the notoriously elusive anaplerotic node in central carbon metabolism and revealed possible operation modes. Our study provides a powerful and statistically rigorous platform to simultaneously infer carbon and nitrogen metabolism in any biological system.


Assuntos
Carbono , Nitrogênio , Carbono/metabolismo , Isótopos de Carbono/metabolismo , Nitrogênio/metabolismo , Análise do Fluxo Metabólico , Teorema de Bayes , Modelos Biológicos
3.
Anal Chem ; 95(39): 14727-14735, 2023 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-37725657

RESUMO

In this work, we demonstrate the development and first application of nanocapillary sampling followed by analytical flow liquid chromatography-mass spectrometry for single-cell lipidomics. Around 260 lipids were tentatively identified in a single cell, demonstrating remarkable sensitivity. Human pancreatic ductal adenocarcinoma cells (PANC-1) treated with the chemotherapeutic drug gemcitabine can be distinguished from controls solely on the basis of their single-cell lipid profiles. Notably, the relative abundance of LPC(0:0/16:0) was significantly affected in gemcitabine-treated cells, in agreement with previous work in bulk. This work serves as a proof of concept that live cells can be sampled selectively and then characterized using automated and widely available analytical workflows, providing biologically relevant outputs.


Assuntos
Lipidômica , Neoplasias Pancreáticas , Humanos , Cromatografia Líquida , Lipidômica/métodos , Lipídeos/análise , Espectrometria de Massas em Tandem , Neoplasias Pancreáticas/tratamento farmacológico , Gencitabina , Neoplasias Pancreáticas
4.
Molecules ; 28(15)2023 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-37570657

RESUMO

Time-of-flight secondary ion mass spectrometry (ToF-SIMS) has been shown to enhance fingermark recovery compared to standard processes used by police forces, but there is no data to show how generally applicable the improvement is. Additionally, ToF-SIMS can be run in either positive or negative ion mode (or both), and there is no data on which mode of operation is most effective at revealing fingerprints. This study aims to fill these gaps by using ToF-SIMS to image fingerprints deposited on two common exhibit-type surfaces (polyethylene and stainless steel) using 10 donors and ageing fingerprints in either ambient, rainwater, or underground for 1 and 5 months. In all, 120 fingerprints were imaged using ToF-SIMS, and each was run in positive and negative modes. A fingerprint expert compared the fingerprint ridge detail produced by the standard process to the ToF-SIMS images. In over 50% of the samples, ToF-SIMS was shown to improve fingerprint ridge detail visualised by the respective standard process for all surfaces tested. In over 90% of the samples, the ridge detail produced by ToF-SIMS was equivalent to standard development across all different ageing and exposure conditions. The data shows that there is a benefit to running the ToF-SIMS in both positive and negative modes, even if no ridge detail was seen in one mode.

5.
Anal Chem ; 94(34): 11798-11806, 2022 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-35981335

RESUMO

Elemental imaging is widely used for imaging cells and tissues but rarely in combination with organic mass spectrometry, which can be used to profile lipids and measure drug concentrations. Here, we demonstrate how elemental imaging and a new method for spatially resolved lipidomics (DAPNe-LC-MS, based on capillary microsampling and liquid chromatography mass spectrometry) can be used in combination to probe the relationship between metals, drugs, and lipids in discrete areas of tissues. This new method for spatial lipidomics, reported here for the first time, has been applied to rabbit lung tissues containing a lesion (caseous granuloma) caused by tuberculosis infection. We demonstrate how elemental imaging with spatially resolved lipidomics can be used to probe the association between ion accumulation and lipid profiles and verify local drug distribution.


Assuntos
Lipidômica , Lipídeos , Animais , Biomarcadores , Cromatografia Líquida/métodos , Lipídeos/análise , Espectrometria de Massas/métodos , Coelhos
6.
Anal Chem ; 93(40): 13450-13458, 2021 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-34597513

RESUMO

Elemental and molecular imaging play a crucial role in understanding disease pathogenesis. To accurately correlate elemental and molecular markers, it is desirable to perform sequential elemental and molecular imaging on a single-tissue section. However, very little is known about the impact of performing these measurements in sequence. In this work, we highlight some of the challenges and successes associated with performing elemental mapping in sequence with mass spectrometry imaging. Specifically, the feasibility of molecular mapping using the mass spectrometry imaging (MSI) techniques matrix-assisted laser desorption ionization (MALDI) and desorption electrospray ionization (DESI) in sequence with the elemental mapping technique particle-induced X-ray emission (PIXE) is explored. Challenges for integration include substrate compatibility, as well as delocalization and spectral changes. We demonstrate that while sequential imaging comes with some compromises, sequential DESI-PIXE imaging is sufficient to correlate sulfur, iron, and lipid markers in a single tissue section at the 50 µm scale.


Assuntos
Oligoelementos , Lipídeos , Imagem Molecular , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Enxofre
7.
Anal Chem ; 92(14): 9847-9855, 2020 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-32545955

RESUMO

The use of a low aerosol dispersion ablation chamber within a laser ablation inductively coupled plasma mass spectrometer (LA-ICP-MS) setup allows for high-resolution, high-speed imaging of the distribution of elements within a sample. Here we show how this enhanced capability creates new analytical problems and solutions. We report the distribution of platinum at the cellular level in non-small cell lung cancer (NSCLC) explant models after treatment with clinically relevant doses of cisplatin. This revealed for the first time a correlation between the platinum signal and the presence of carbon deposits within lung tissue. We show how complementary ion beam analysis techniques, particle-induced X-ray emission (PIXE) and elastic backscattering spectrometry (EBS), can be used to explore potential matrix effects in LA-ICP-MS data. For these samples, it was confirmed that the enhancement was unlikely to have resulted from a matrix effect alone. Thus, the presence of carbon deposits within tissue has potential implications for the effective distribution of the cisplatin drug.


Assuntos
Cisplatino/uso terapêutico , Neoplasias Pulmonares/química , Neoplasias Pulmonares/tratamento farmacológico , Espectrometria de Massas/métodos , Antineoplásicos/uso terapêutico , Carbono/química , Carcinoma Pulmonar de Células não Pequenas , Humanos , Terapia a Laser , Esferoides Celulares , Técnicas de Cultura de Tecidos
8.
Analyst ; 145(8): 3038-3048, 2020 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-32134419

RESUMO

The use of synthetic stimulants, including designer cathinones, remains a significant concern worldwide. Thus, the detection and identification of synthetic cathinones in biological matrices is of paramount importance for clinical and forensic laboratories. In this study, distribution of mephedrone and its metabolites was investigated in fingerprints. Following a controlled human mephedrone administration (100 mg nasally insufflated), two mass spectrometry-based methods for fingerprint analysis have been evaluated. The samples deposited on triangular pieces of chromatography paper were directly analysed under ambient conditions by paper spray-mass spectrometry (PS-MS) while those deposited on glass cover slips were extracted and analysed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The LC-MS/MS method was 5-6 times more sensitive than PS-MS but required sample preparation and longer analysis time. Mephedrone was detected in 62% and in 38% of all post-administration samples analysed by LC-MS/MS and PS-MS, respectively. Nor-mephedrone was the only metabolite detected in 3.8% of all samples analysed by LC-MS/MS. A large inter- and intra-subject variation was observed for mephedrone which may be due to several factors, such as the applied finger pressure, angle and duration of contact with the deposition surface and inability to control the 'amount' of collected fingerprint deposits. Until these limitations are addressed, we suggest that the sole use of fingerprints can be a useful diagnostic tool in qualitative rather than quantitative analysis, and requires a confirmatory analysis in a different biological matrix.


Assuntos
Estimulantes do Sistema Nervoso Central/análise , Cromatografia Líquida de Alta Pressão/métodos , Dermatoglifia , Metanfetamina/análogos & derivados , Detecção do Abuso de Substâncias/métodos , Espectrometria de Massas em Tandem/métodos , Administração por Inalação , Estimulantes do Sistema Nervoso Central/administração & dosagem , Estimulantes do Sistema Nervoso Central/metabolismo , Humanos , Masculino , Metanfetamina/administração & dosagem , Metanfetamina/análise , Metanfetamina/metabolismo , Papel , Espectrometria de Massas em Tandem/instrumentação
9.
Anal Chem ; 91(24): 15411-15417, 2019 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-31747247

RESUMO

Direct analyte-probed nanoextraction (DAPNe) is a technique that allows extraction of drug and endogenous compounds from a discrete location on a tissue sample using a nano capillary filled with solvent. Samples can be extracted from spot diameters as low as 6 µm. Studies previously undertaken by our group have shown that the technique can provide good precision (5%) for analyzing drug molecules in 150 µm diameter areas of homogenized tissue, provided an internal standard is sprayed on to the tissue prior to analysis. However, without an isotopically labeled standard, the repeatability is poor, even after normalization to the spot area or matrix compounds. By application to tissue homogenates spiked with drug compounds, we can demonstrate that it is possible to significantly improve the repeatability of the technique by incorporating a liquid chromatography separation step. Liquid chromatography is a technique for separating compounds prior to mass spectrometry (LC-MS) which enables separation of isomeric compounds that cannot be discriminated using mass spectrometry alone, as well as reducing matrix interferences. Conventionally, LC-MS is carried out on bulk or homogenized samples, which means analysis is essentially an average of the sample and does not take into account discrete areas. This work opens a new opportunity for spatially resolved liquid chromatography mass spectrometry with precision better than 20%.

10.
Artigo em Inglês | MEDLINE | ID: mdl-31414505

RESUMO

RATIONALE: Paper spray offers a rapid screening test without the need for sample preparation. The incomplete extraction of paper spray allows for further testing using more robust, selective and sensitive techniques such as liquid chromatography/mass spectrometry (LC/MS). Here we develop a two-step process of paper spray followed by LC/MS to (1) rapidly screen a large number of samples and (2) confirm any disputed results. This demonstrates the applicability for testing medication adherence from a fingerprint. METHODS: Following paper spray analysis, drugs of abuse samples were analysed using LC/MS. All analyses were completed using a Q Exactive™ Plus Orbitrap™ mass spectrometer. This two-step procedure was applied to fingerprints collected from patients on a maintained dose of the antipsychotic drug quetiapine. RESULTS: The extraction efficiency of paper spray for two drugs of abuse and metabolites was found to be between 15 and 35% (analyte dependent). For short acquisition times, the extraction efficiency was found to vary between replicates by less than 30%, enabling subsequent analysis by LC/MS. This two-step process was then applied to fingerprints collected from two patients taking the antipsychotic drug quetiapine, which demonstrates how a negative screening result from paper spray can be resolved using LC/MS. CONCLUSIONS: We have shown for the first time the sequential analysis of the same sample using paper spray and LC/MS, as well as the detection of an antipsychotic drug from a fingerprint. We propose that this workflow may also be applied to any type of sample compatible with paper spray, and will be especially convenient where only one sample is available for analysis.

11.
Anal Chem ; 90(20): 12094-12100, 2018 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-30260213

RESUMO

Direct analyte probed nanoextraction (DAPNe) is a method of extracting material from a microscale region of a sample and provides the opportunity for detailed mass spectrometry analysis of extracted analytes from a small area. The technique has been shown to provide enhanced sensitivity compared with bulk analysis by selectively removing analytes from their matrix and has been applied for selective analysis of single cells and even single organelles. However, the quantitative capabilities of the technique are yet to be fully evaluated. In this study, various normalization techniques were investigated in order to improve the quantitative capabilities of the technique. Two methods of internal standard incorporation were applied to test substrates, which were designed to replicate biological sample matrices. Additionally, normalization to the extraction spot area and matrix compounds were investigated for suitability in situations when an internal standard is not available. The variability observed can be significantly reduced by using a sprayed internal standard and, in some cases, by normalizing to the extracted area.


Assuntos
Fígado/citologia , Nanotecnologia , Análise de Célula Única , Humanos , Espectrometria de Massas , Organelas/química
12.
Clin Chem ; 64(6): 909-917, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29567660

RESUMO

BACKGROUND: Recent publications have explored the possibility of using fingerprints to confirm drug use, but none has yet dealt with environmental contamination from fingertips. Here we explored the possibility of establishing an environmental cutoff for drug testing from a single fingerprint. METHODS: Fingerprint samples (n = 100) were collected from the hands of 50 nondrug users before and after handwashing to establish separate environmental cutoff values and testing protocols for cocaine, benzoylecgonine, heroin, and 6-monoacetylmorphine. The cutoff was challenged by testing the fingerprints of drug-free volunteers after shaking hands with drug users. Fingerprints from patients who testified to taking cocaine (n = 32) and heroin (n = 24) were also collected and analyzed. RESULTS: A different cutoff value needed to be applied, depending on whether the fingerprints were collected as presented or after handwashing. Applying these cutoffs gave a 0% false-positive rate from the drug-free volunteers. After application of the cutoff, the detection rate (compared to patient testimony) for washed hands of patients was 87.5% for cocaine use and 100% for heroin use. CONCLUSIONS: Fingerprints show enhanced levels of cocaine, heroin, and their respective metabolites in patients who testified to taking the substances, compared with the population of naïve drug users surveyed, and a cutoff (decision level) can be established. The cutoff is robust enough to account for small increases in analyte observed after secondary transfer.


Assuntos
Cocaína/análise , Dedos , Heroína/análise , Pele/química , Detecção do Abuso de Substâncias/métodos , Estudos de Casos e Controles , Cocaína/análogos & derivados , Desinfecção das Mãos , Humanos , Limite de Detecção , Derivados da Morfina/análise , Reprodutibilidade dos Testes , Transtornos Relacionados ao Uso de Substâncias/diagnóstico
13.
Clin Chem ; 63(11): 1745-1752, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28939761

RESUMO

BACKGROUND: Paper spray mass spectrometry (PS-MS) is a technique that has recently emerged and has shown excellent analytical sensitivity to a number of drugs in blood. As an alternative to blood, fingerprints have been shown to provide a noninvasive and traceable sampling matrix. Our goal was to validate the use of fingerprint samples to detect cocaine use. METHODS: Samples were collected on triangular pieces (168 mm2) of washed Whatman Grade I chromatography paper. Following application of internal standard, spray solvent and a voltage were applied to the paper before mass spectrometry detection. A fingerprint visualization step was incorporated into the analysis procedure by addition of silver nitrate solution and exposing the sample to ultraviolet light. RESULTS: Limits of detection for cocaine, benzoylecgonine, and methylecgonine were 1, 2, and 31 ng/mL respectively, with relative standard deviations < 33%. No matrix effects were observed. Analysis of 239 fingerprint samples yielded a 99% true-positive rate and a 2.5% false-positive rate, based on the detection of cocaine, benzoylecgonine, or methylecgonine with use of a single fingerprint. CONCLUSIONS: The method offers a qualitative and noninvasive screening test for cocaine use. The analysis method developed is rapid (4 min/sample) and requires no sample preparation.


Assuntos
Cocaína/análogos & derivados , Cocaína/análise , Espectrometria de Massas/métodos , Detecção do Abuso de Substâncias/métodos , Dermatoglifia , Humanos , Limite de Detecção , Papel , Saliva/química , Suor/química
14.
Analyst ; 140(18): 6254-9, 2015 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-25977942

RESUMO

Latent fingerprints provide a potential route to the secure, high throughput and non-invasive detection of drugs of abuse. In this study we show for the first time that the excreted metabolites of drugs of abuse can be detected in fingerprints using ambient mass spectrometry. Fingerprints and oral fluid were taken from patients attending a drug and alcohol treatment service. Gas chromatography mass spectrometry (GC-MS) was used to test the oral fluid of patients for the presence of cocaine and benzoylecgonine. The corresponding fingerprints were analysed using Desorption Electrospray Ionization (DESI) which operates under ambient conditions and Ion Mobility Tandem Mass Spectrometry Matrix Assisted Laser Desorption Ionization (MALDI-IMS-MS/MS) and Secondary Ion Mass Spectrometry (SIMS). The detection of cocaine, benzoylecgonine (BZE) and methylecgonine (EME) in latent fingerprints using both DESI and MALDI showed good correlation with oral fluid testing. The sensitivity of SIMS was found to be insufficient for this application. These results provide exciting opportunities for the use of fingerprints as a new sampling medium for secure, non-invasive drug detection. The mass spectrometry techniques used here offer a high level of selectivity and consume only a small area of a single fingerprint, allowing repeat and high throughput analyses of a single sample.


Assuntos
Cocaína/análogos & derivados , Cocaína/análise , Dermatoglifia , Espectrometria de Massas/métodos , Detecção do Abuso de Substâncias/métodos , Pressão Atmosférica , Humanos , Propriedades de Superfície , Fatores de Tempo
15.
Heliyon ; 10(7): e28233, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38596052

RESUMO

UNESCO's Intergovernmental Oceanographic Commission launched the United Nations Decade of Ocean Science for Sustainable Development in 2021 to boost global and sustainable Ocean governance. The initiative resulted from historical and political dynamics at the global and lower political scales, with maritime environmental and economic concerns becoming more prominent in 2010. The Ocean Decade's pillars include science and research, sustainability, conservation, and bridging gaps for a global Ocean-Climate-Biodiversity nexus. The Sustainable Development Goals recognized the importance of oceans and marine resources, and the Ocean was officially perceived as a determining factor of Climate Change at CoP 21 in 2015. Portugal has built integrated and far-reaching policies for ocean governance, including significant involvement with an international perspective since the Lisbon World Exhibition in 1998. In addition, the national government established a Ministry of the Sea in 2015 to re-develop relations with its maritime space. This article analyzes and compares the discourse of the United Nations' Sustainable Development Goals reports and the Portuguese government programs (2005-2022) to explore the prominent trends in Portuguese Ocean governance discourse and how global and national perspectives interact. Through this case study, the research aims to develop insights into the multiscalar impacts of promoting global and sustainable Ocean governance and its interaction with national perspectives.

16.
Biomedicines ; 11(12)2023 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-38137361

RESUMO

Prostate cancer (PCa) remains a significant global health concern, being a major cause of cancer morbidity and mortality worldwide. Furthermore, profound understanding of the disease is needed. Prostate inflammation caused by external or genetic factors is a central player in prostate carcinogenesis. However, the mechanisms underlying inflammation-driven PCa remain poorly understood. This review dissects the diagnosis methods for PCa and the pathophysiological mechanisms underlying the disease, clarifying the dynamic interplay between inflammation and leukocytes in promoting tumour development and spread. It provides updates on recent advances in elucidating and treating prostate carcinogenesis, and opens new insights for the use of bioactive compounds in PCa. Polyphenols, with their noteworthy antioxidant and anti-inflammatory properties, along with their synergistic potential when combined with conventional treatments, offer promising prospects for innovative therapeutic strategies. Evidence from the use of polyphenols and polyphenol-based nanoparticles in PCa revealed their positive effects in controlling tumour growth, proliferation, and metastasis. By consolidating the diverse features of PCa research, this review aims to contribute to increased understanding of the disease and stimulate further research into the role of polyphenols and polyphenol-based nanoparticles in its management.

17.
Artigo em Inglês | MEDLINE | ID: mdl-37754575

RESUMO

Noncommunicable diseases (NCDs) present a major public health challenge, prompting their inclusion in the United Nations' 2030 Agenda for Sustainable Development. In response, the World Health Organization (WHO) has implemented various initiatives, including a comprehensive monitoring framework with global targets and indicators. However, the extent to which these initiatives have shaped the scientific discourse remains unclear. This article addresses this knowledge gap through a two-fold approach. Firstly, a bibliometric analysis of 14,187 studies spanning over 60 years is conducted, identifying key contributors and trends. Secondly, the content analysis compares these trends to the goals established by the WHO. The findings indicate that the WHO initiatives have accelerated scientific research, and elevated global targets and indicators as central themes in scholarly discussions, since 2011. This study takes an innovative approach that contributes to the advancement of knowledge in this field, by providing valuable insights into the impact of WHO initiatives on the scientific debate surrounding NCDs, and offering guidance for policymakers, researchers, and stakeholders engaged in combating these diseases.

18.
Sci Justice ; 63(1): 9-18, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36631186

RESUMO

The processes routinely used by police forces to visualise fingermarks in casework may not provide sufficient ridge pattern quality to aid an investigation. Time of Flight-Secondary Ion Mass Spectrometry (ToF-SIMS) has been proposed as a technique to enhance fingermark recovery. The technique is currently designated a Category C process in the Fingermark Visualisation Manual (FVM) as it shows potential for effective fingermark visualisation but has not yet been fully evaluated. Here the sensitivity of ToF-SIMS on three common exhibit-type surfaces - paper, polyethylene and stainless-steel was compared to standard processes. An adapted Home Office grading scale was used to evaluate the efficacy of fingerprint development by ToF-SIMS and to provide a framework for comparison with standard processes. ToF-SIMS was shown to visualise more fingerprints than the respective standard process, for all surfaces tested. In addition, ToF-SIMS was applied after the standard processes and successfully enhanced the fingerprint detail, even when the standard process failed to visualise ridge detail. This demonstrates the benefit for incorporating it into current operational fingermark development workflows. Multivariate analysis (MVA), using simsMVA, was additionally explored as a method to simplify the data analysis and image generation process.


Assuntos
Dermatoglifia , Espectrometria de Massa de Íon Secundário , Humanos , Espectrometria de Massa de Íon Secundário/métodos , Polícia , Análise Multivariada
19.
Behav Sci (Basel) ; 13(4)2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-37102827

RESUMO

This work aims to clarify the psychosocial variables that lead women to undertake and those that prevent them from doing so. Two studies were conducted using a mixed methodology to compensate for the inherent weaknesses of using each approach. The first study was based on the collection of quantitative data using the GloPEW questionnaire with a sample of 296 people. The second study, of a qualitative nature, was carried out through focus groups with a sample of 26 people. The results show that self-efficacy and emotional intelligence are the main factors to develop to promote entrepreneurship among women. Although the data show statistical strength, it seems necessary to expand the sample and incorporate more profiles of female entrepreneurs, for example, with different levels of training, given the complexity and variety of intervening factors.

20.
Metabolites ; 13(2)2023 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-36837881

RESUMO

The colocation of elemental species with host biomolecules such as lipids and metabolites may shed new light on the dysregulation of metabolic pathways and how these affect disease pathogeneses. Alkali metals have been the subject of extensive research, are implicated in various neurodegenerative and infectious diseases and are known to disrupt lipid metabolism. Desorption electrospray ionisation (DESI) is a widely used approach for molecular imaging, but previous work has shown that DESI delocalises ions such as potassium (K) and chlorine (Cl), precluding the subsequent elemental analysis of the same section of tissue. The solvent typically used for the DESI electrospray is a combination of methanol and water. Here we show that a novel solvent system, (50:50 (%v/v) MeOH:EtOH) does not delocalise elemental species and thus enables elemental mapping to be performed on the same tissue section post-DESI. Benchmarking the MeOH:EtOH electrospray solvent against the widely used MeOH:H2O electrospray solvent revealed that the MeOH:EtOH solvent yielded increased signal-to-noise ratios for selected lipids. The developed multimodal imaging workflow was applied to a lung tissue section containing a tuberculosis granuloma, showcasing its applicability to elementally rich samples displaying defined structural information.

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