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1.
Undersea Hyperb Med ; 51(1): 47-51, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38615353

RESUMO

Barodontalgia, barometric pressure-induced dental pain, may occur during hyperbaric oxygen(HBO2) therapy due to pressure changes. This case report presents an 8-year-old male patient with barodontalgia. The patient declared a severe toothache during HBO2 therapy. The diving medicine specialist referred the patient to the dental clinician immediately. On clinical examination, the pain was thought to be caused by caries lesions of the deciduous teeth in the left maxillary molar region. Tooth extraction was suggested. After extraction, the patient continued hyperbaric oxygen therapy sessions without any pain. The patient was recommended for an intraoral and radiographic examination session one week after the extraction. In conclusion, caries lesions and faulty restorations should be examined before hyperbaric oxygen therapy sessions. Even though barodontalgia is a rare phenomenon, dental examination is essential to avoid these kinds of pain-related complications. All carious lesions and defective restorations must be treated, if necessary. Removal of faulty restorations and management of inflammation as part of the treatment is suggested before exposure to pressure changes.


Assuntos
Oxigenoterapia Hiperbárica , Odontalgia , Masculino , Humanos , Criança , Odontalgia/etiologia , Odontalgia/terapia , Pressão Atmosférica , Oxigênio , Inflamação
2.
Rapid Commun Mass Spectrom ; 38(12): e9755, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38600731

RESUMO

RATIONALE: Atmospheric pressure matrix-assisted laser desorption/ionization (AP-MALDI) mass spectrometry has enabled the untargeted analysis and imaging of neuropeptides and proteins in biological tissues under ambient conditions. Sensitivity in AP-MALDI can be improved by using sample-specific preparation methods. METHODS: A comprehensive and detailed optimization strategy including instrument parameters, matrix spraying and sample tissue washing pretreatment was implemented to enhance the sensitivity and coverage of neuropeptides in mouse pituitary tissues by commercial AP-MALDI mass spectrometry imaging (MSI). RESULTS: The sensitivity of a commercial AP-MALDI system for endogenous neuropeptides in mouse pituitary was enhanced by up to 15.2-fold by shortening the transmission gap from the sample plate to the inlet, attaching copper adhesive tape to an indium tin oxide-coated glass slide, optimizing the matrix spray solvent and using sample tissue washing pretreatment. Following careful optimization, the distributions of nine endogenous neuropeptides were successfully visualized in the pituitary. Furthermore, the quantitative capability of AP-MALDI for neuropeptides was evaluated and the concentrations of neuropeptides oxytocin and vasopressin in the pituitary posterior lobe were increased approximately twofold under hypertonic saline stress. CONCLUSION: Mouse pituitary neuropeptides have emerged as important signaling molecules due to their role in stress response. This work indicates the potential of modified AP-MALDI as a promising AP MSI method for in situ visualization and quantification of neuropeptides in complex biological tissues.


Assuntos
Neuropeptídeos , Camundongos , Animais , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Neuropeptídeos/análise , Pressão Atmosférica , Lasers
3.
ACS Appl Mater Interfaces ; 16(11): 13597-13610, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38453642

RESUMO

Atmospheric pressure coaxial gaseous discharge tubes (DTs) with helium have demonstrated potential for in vitro inactivation or sensitization of glioblastoma cancer cells. Here, we study the effect of two configurations of the DT electrode system on its electromagnetic emissivity as well as other physical factors (heating and UV emission) that form in the vicinity of this device. We demonstrate that the configuration of the DT electrodes that concentrates the discharge streamers near the top of the device has a distant (cm scale) deactivation effect on U87-MG glioblastoma cancer cells when irradiated, without measurable UV components in the DT optical emission spectra. This effect persists even through different barriers such as glass, plastic, or quartz Petri dishes but is eliminated when glass or plastic dishes are filled with water. These findings demonstrate the potential for development of noninvasive, physical-based treatment methods of deep-tissue tumors.


Assuntos
Glioblastoma , Gases em Plasma , Humanos , Gases em Plasma/farmacologia , Hélio , Glioblastoma/terapia , Fenômenos Eletromagnéticos , Pressão Atmosférica
4.
Curr Pain Headache Rep ; 28(4): 181-187, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38358443

RESUMO

PURPOSE OF REVIEW: Many patients with migraine report their attacks are triggered by various weather anomalies. Studies have shown mixed results regarding the association of migraine to weather changes. The purpose of the current review is to compile the most up-to-date research studies on how weather may affect migraine. In addition, we explore the association between weather and other inflammatory disease states as well as neurotransmitters. RECENT FINDINGS: Migraine attacks can be related to weather variables such as barometric pressure, humidity, and wind. However, the results of recent studies are inconsistent; weathers' effect on migraine attacks is around 20%. However, very strong weather factors have a more significant effect on migraine attack variables. Many individuals identify weather as a migraine attack trigger, yet we see no causative relationship between weather and migraine patterns. The outcomes of studies indicate mixed results and reflect individual variation in how weather can impact migraine patterns. Similar relationships can be seen with other rheumatologic and pain conditions in general. Overall, the combination of weather plus other factors appears to be a more significant migraine trigger.


Assuntos
Transtornos de Enxaqueca , Tempo (Meteorologia) , Humanos , Transtornos de Enxaqueca/epidemiologia , Transtornos de Enxaqueca/etiologia , Pressão Atmosférica
5.
Sensors (Basel) ; 24(2)2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38257541

RESUMO

This study's primary objective was to identify individuals whose physiological responses deviated from the rest of the study population by automatically monitoring atmospheric pressure levels to which they are exposed and using parameters derived from their heart rate variability (HRV). To achieve this, 28 volunteers were placed in a dry hyperbaric chamber, where they experienced varying pressures from 1 to 5 atmospheres, with five sequential stops lasting five minutes each at different atmospheric pressures. The HRV was dissected into two components: the respiratory component, which is linked to respiration; and the residual component, which is influenced by factors beyond respiration. Nine parameters were assessed, including the respiratory rate, four classic HRV temporal parameters, and four frequency parameters. A k-nearest neighbors classifier based on cosine distance successfully identified the atmospheric pressures to which the subjects were exposed to. The classifier achieved an 88.5% accuracy rate in distinguishing between the 5 atm and 3 atm stages using only four features: respiratory rate, heart rate, and two frequency parameters associated with the subjects' sympathetic responses. Furthermore, the study identified 6 out of 28 subjects as having atypical responses across all pressure levels when compared to the majority. Interestingly, two of these subjects stood out in terms of gender and having less prior diving experience, but they still exhibited normal responses to immersion. This suggests the potential for establishing distinct safety protocols for divers based on their previous experience and gender.


Assuntos
Respiração , Taxa Respiratória , Humanos , Frequência Cardíaca , Atmosfera , Pressão Atmosférica
6.
Int J Mol Sci ; 25(2)2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38279247

RESUMO

Media exposed to atmospheric pressure plasma (APP) produce reactive oxygen and nitrogen species (RONS), with hydrogen peroxide (H2O2), nitrite (NO2-), and nitrate (NO3-) being among the most detected species due to their relatively long lifetime. In this study, a standardized microwave-excited (ME) APP jet (APPJ) source was employed to produce gaseous RONS to treat liquid samples. The source was a commercially available plasma jet, which generated argon plasma utilizing a coaxial transmission line resonator at the operating frequency of 2.45 GHz. An ultraviolet-visible spectrophotometer was used to measure the concentrations of H2O2 and NO3- in plasma-activated media (PAM). Three different types of media (deionized water, Hank's balanced salt solution, and cell culture solution Dulbecco's modified eagles medium [DMEM]) were utilized as liquid samples. Among these media, the plasma-treated DMEM was observed to have the highest levels of H2O2 and NO3-. Subsequently, the feasibility of using argon ME-APPJ-activated DMEM (PAM) as an adjuvant to enhance the therapeutic effects of cisplatin on human bladder cancer cells (T-24) was investigated. Various cancer cell lines, including T-24 cells, treated with PAM were observed in vitro for changes in cell viability using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. A viability reduction was detected in the various cancer cells after incubation in PAM. Furthermore, the study's results revealed that PAM was effective against cisplatin-resistant T-24 cells in vitro. In addition, a possible connection between HER expression and cell viability was sketched.


Assuntos
Gases em Plasma , Neoplasias da Bexiga Urinária , Humanos , Cisplatino/farmacologia , Peróxido de Hidrogênio/farmacologia , Micro-Ondas , Pressão Atmosférica , Espécies Reativas de Oxigênio/metabolismo , Espécies Reativas de Nitrogênio/metabolismo , Neoplasias da Bexiga Urinária/tratamento farmacológico , Gases em Plasma/farmacologia
7.
Life Sci Space Res (Amst) ; 40: 115-125, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38245336

RESUMO

The circadian clock extensively regulates physiology and behavior. In space, astronauts encounter many environmental factors that are dramatically different from those on Earth; however, the effects of these factors on circadian rhythms and the mechanisms remain largely unknown. The present study aimed to investigate the changes in the mouse diurnal rhythm and gut microbiome under simulated space capsule conditions, including microgravity, noise and low atmospheric pressure (LAP). Noise and LAP were loaded in the capsule while the conditions in the animal room remained constant. The mice in the capsule showed disturbed locomotor rhythms and faster adaptation to a 6-h phase advance. RNA sequencing of hypothalamus samples containing the suprachiasmatic nucleus (SCN) revealed that microgravity simulated by hind limb unloading (HU) and exposure to noise and LAP led to decreases in the quantities of differentially expressed genes (DEGs), including circadian clock genes. Changes in the rhythmicity of genes implicated in pathways of cardiovascular deconditioning and more concentrated phases were found under HU or noise and LAP. Furthermore, 16S rRNA sequencing revealed dysbiosis in the gut microbiome, and noise and LAP may repress the temporal discrepancy in the microbiome community structure induced by microgravity. Changes in diurnal oscillations were observed in a number of gut bacteria with critical physiological consequences on metabolism and immunodefense. We also found that the superimposition of noise and LAP may repress normal changes in global gene expression and adaptation in the gut microbiome. Our data demonstrate that in addition to microgravity, exposure to noise and LAP affect the robustness of circadian rhythms and the community structure of the gut microbiome, and these factors may interfere with each other in their adaptation to respective conditions. These findings are important for furthering our understanding of the alterations in circadian rhythms in the complex environment of space.


Assuntos
Microbioma Gastrointestinal , Ausência de Peso , Camundongos , Animais , Ausência de Peso/efeitos adversos , RNA Ribossômico 16S/genética , Ritmo Circadiano/genética , Pressão Atmosférica
8.
J Pharmacol Sci ; 154(2): 47-51, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38246727

RESUMO

Goreisan is a Kampo medicine used to treat headaches associated with climate change. Here, by using an implantable complementary metal-oxide-semiconductor (CMOS) device, we evaluated the effects of Goreisan and loxoprofen on cerebral blood flow (CBF) dynamics associated with barometric pressure fluctuations in freely moving mice. In the vehicle group, decreasing barometric pressure increased CBF that was prevented by Goreisan and loxoprofen. Notably, Goreisan, but not loxoprofen, reduced CBF after returning to atmospheric pressure. These results indicate that, unlike the mechanism of action of antipyretic analgesics, Goreisan normalizes CBF abnormalities associated with barometric pressure fluctuations by actively reducing CBF increase.


Assuntos
Pressão Atmosférica , Circulação Cerebrovascular , Medicamentos de Ervas Chinesas , Fenilpropionatos , Feminino , Animais , Camundongos , Camundongos Endogâmicos C57BL
9.
Talanta ; 271: 125673, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38244311

RESUMO

Photoionization-ion trap mass spectrometry (PI-ITMS) is one of the major directions of mass spectrometer miniaturization because of its great potential for rapid on-site VOCs detection in many cases. Traditionally, PI has always been investigated separately and is restrained by ion transmission structure, so a new structure needs to be designed and investigated for simplifying and improving the ion transmission efficiency. Interestingly, our preliminary experiments found that the signal intensity and mass range can be effectively improved by combing atmospheric pressure photoionization (APPI) and low-pressure photoionization (LPPI). Therefore, in this paper, a new dual photoionization - ion trap mass spectrometry (DPI-ITMS) was developed, explored and used to directly analyze complex VOCs. Compared with traditional single PI configuration, it presents two obvious merits: (1) simplified ion transmission structure, eliminating the need to use deflection electrode to repel ions and avoiding breakdown risk. (2) some missing/weak low m/z ion mass spectral peaks in APPI and some high m/z ion mass spectral peaks in LPPI were improved in DPI detection mode. In addition, by combining multivariate statistical analysis, we preliminary achieved in differentiating fruit types and maturity level. In summary, we concluded that the developed DPI-ITMS has moderate detection sensitivity (limited by the homemade ITMS, 0.1-1 ppmv with RSD of 6.36 %), and the DPI-ITMS configuration can be referenced by future PI-MS, and this study also provides a high-throughput, simple, noninvasive and no chemical contamination solution for analyzing main VOCs in fruit aroma.


Assuntos
Frutas , Odorantes , Cromatografia Gasosa-Espectrometria de Massas , Pressão Atmosférica , Contaminação de Medicamentos
10.
PLoS One ; 19(1): e0296907, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38236894

RESUMO

In high-altitude areas, the air is thin and the atmospheric pressure is low, which can affect the performance of centrifugal fans and aerodynamic noise. In this paper, steady and unsteady simulations of a centrifugal fan flow field are performed at altitudes of 0, 1000, 2000, 3000, 4000, and 5000 m, and the Ffowcs Williams-Hawkings equation is used to predict the aerodynamic noise of the fan. The results indicate that the tonal and broadband noise generated by the fan decrease with increasing altitude, and the A-weighted sound pressure level of each frequency band of the fan decreases when the air volume is held fixed. The maximum sound power level Lwmax, sound pressure pulsation interval, and total noise sound pressure level Lp decrease linearly with increasing altitude. For every 1000 m increase in altitude, Lwmax and Lp decrease by 0.45 dB and 1.05 dB respectively. The fan noise characteristics, performance parameters, and human auditory perception are the main factors that affect the establishment of fan noise standards in high-altitude areas.


Assuntos
Altitude , Ruído , Humanos , Acústica , Som , Pressão Atmosférica
11.
Int J Food Microbiol ; 410: 110474, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-37984215

RESUMO

Eggshell cuticles are first lines of defense against egg-associated pathogens, such as Salmonella enterica serovar Enteritidis (SE). Infections from eggs contaminated with this strain remain a significant risk. In addition, changes in the cuticle are closely related to changes in egg safety. The emerging non-thermal atmospheric pressure plasma technology enables a high rate of microbial inactivation at near-ambient temperatures, making it ideal for food safety applications. This study examines the effects of a cold atmospheric pressure air plasma jet (CAAP-J) on eggshell cuticle and egg quality whilst inactivating SE. Shell eggs inoculated with SE (7 log10 cfu/egg) were used as the samples to test the decontamination performance of the device. The tests were conducted using an industrial CAAP-J with different power levels (600-800 W), exposure times (60-120 s), at a fixeddistance of 20 mm from the plasma jet and an air flow rate of 3600 L/h. It was found that the best results were obtained after 120 s at maximum plasma power (800 W). Subsequent to the implementation of this plasma procedure, it was determined that no viable cells could be detected. After CAAP-J treatment, the temperature remains below 50.5 °C, thereby minimizing the risk of altering egg quality. All specific measurements (egg white pH, yolk pH, yolk color, HU, and eggshell breaking strength) have shown that CAAP-J treatment has no negative effect on egg quality. No changes in eggshell cuticle quality after CAAP-J treatment was confirmed through scanning electron microscope (SEM).


Assuntos
Gases em Plasma , Salmonella enterica , Animais , Gases em Plasma/farmacologia , Microbiologia de Alimentos , Desinfecção , Ovos , Salmonella enteritidis/fisiologia , Casca de Ovo , Pressão Atmosférica , Galinhas
12.
J Environ Sci (China) ; 138: 516-530, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38135417

RESUMO

On-line chemical characterization of atmospheric particulate matter (PM) with soft ionization technique and ultrahigh-resolution Mass Spectrometry (UHRMS) provides molecular information of organic constituents in real time. Here we describe the development and application of an automatic measurement system that incorporates PM2.5 sampling, thermal desorption, atmospheric pressure photoionization, and UHRMS analysis. Molecular formulas of detected organic compounds were deducted from the accurate (±10 ppm) molecular weights obtained at a mass resolution of 100,000, allowing the identification of small organic compounds in PM2.5. Detection efficiencies of 28 standard compounds were determined and we found a high sensitivity and selectivity towards organic amines with limits of detection below 10 pg. As a proof of principle, PM2.5 samples collected off-line in winter in the urban area of Beijing were analyzed using the Ionization Module and HRMS of the system. The automatic system was then applied to conduct on-line measurements during the summer time at a time resolution of 2 hr. The detected organic compounds comprised mainly CHON and CHN compounds below 350 m/z. Pronounced seasonal variations in elemental composition were observed with shorter carbon backbones and higher O/C ratios in summer than that in winter. This result is consistent with stronger photochemical reactions and thus a higher oxidation state of organics in summer. Diurnal variation in signal intensity of each formula provides crucial information to reveal its source and formation pathway. In summary, the automatic measurement system serves as an important tool for the on-line characterization and identification of organic species in PM2.5.


Assuntos
Poluentes Atmosféricos , Material Particulado , Material Particulado/análise , Poluentes Atmosféricos/análise , Espectrometria de Massas , Pressão Atmosférica , Aerossóis/análise , Aminas , Monitoramento Ambiental/métodos
13.
Cutis ; 112(5): 241-244, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38091435

RESUMO

Nonthermal atmospheric plasma (NTAP)(also known as cold atmospheric plasma [CAP]) is a rapidly emerging technology showing promising treatment results for a wide variety of dermatologic conditions. Research on NTAP for the treatment of pediatric dermatologic conditions is limited. We conducted a systematic review to elucidate reported applications of NTAP for skin conditions in children. Overall, NTAP offers a promising safety profile and painless treatment option that has the potential to deliver similar efficacy to many standard therapies in pediatric dermatology.


Assuntos
Pressão Atmosférica , Dermatopatias , Criança , Humanos , Dermatopatias/diagnóstico
14.
Int J Mol Sci ; 24(23)2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-38068979

RESUMO

Diabetes is one of the most significant causes of death all over the world. This illness, due to abnormal blood glucose levels, leads to impaired wound healing and, as a result, foot ulcers. These ulcers cannot heal quickly in diabetic patients and may finally result in amputation. In recent years, different research has been conducted to heal diabetic foot ulcers: one of them is using cold atmospheric pressure plasma. Nowadays, cold atmospheric pressure plasma is highly regarded in medicine because of its positive effects and lack of side effects. These conditions have caused plasma to be considered a promising technology in medicine and especially diabetic wound healing because studies show that it can heal chronic wounds that are resistant to standard treatments. The positive effects of plasma are due to different reactive species, UV radiation, and electromagnetic fields. This work reviews ongoing cold atmospheric pressure plasma improvements in diabetic wound healing. It shows that plasma can be a promising tool in treating chronic wounds, including ones resulting from diabetes.


Assuntos
Diabetes Mellitus , Pé Diabético , Gases em Plasma , Humanos , Gases em Plasma/farmacologia , Gases em Plasma/uso terapêutico , Relevância Clínica , Cicatrização , Pé Diabético/tratamento farmacológico , Pressão Atmosférica , Diabetes Mellitus/tratamento farmacológico
15.
ACS Biomater Sci Eng ; 9(12): 6632-6643, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-37982239

RESUMO

Atmospheric pressure plasma treatments are nowadays gaining importance to improve the performance of biomaterials in the orthopedic field. Among those, magnesium phosphate-based cements (MPCs) have recently shown attractive features as bone repair materials. The effect of plasma treatments on such cements, which has not been investigated so far, could represent an innovative strategy to modify MPCs' physicochemical properties and to tune their interaction with cells. MPCs were prepared and treated for 5, 7.5, and 10 min with a cold atmospheric pressure plasma jet. The reactive nitrogen and oxygen species formed during the treatment were characterized. The surfaces of MPCs were studied in terms of the phase composition, morphology, and topography. After a preliminary test in simulated body fluid, the proliferation, adhesion, and osteogenic differentiation of human mesenchymal cells on MPCs were assessed. Plasma treatments induce modifications in the relative amounts of struvite, newberyite, and farringtonite on the surfaces on MPCs in a time-dependent fashion. Nonetheless, all investigated scaffolds show a good biocompatibility and cell adhesion, also supporting osteogenic differentiation of mesenchymal cells.


Assuntos
Osteogênese , Fosfatos , Humanos , Teste de Materiais , Fosfatos/farmacologia , Fosfatos/química , Pressão Atmosférica
16.
Food Res Int ; 174(Pt 1): 113565, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37986520

RESUMO

Chickpea protein (CPI) is a promising dietary protein and potential substitute for soy protein in food product development due to its high protein content and low allergenicity. However, CPI possesses denser tertiary and quaternary structures and contains certain amount of anti-nutritional factors, both of which constrain its functional properties and digestibility. The objective of this study was to assess the effectiveness of atmospheric pressure plasma jets (APPJ) as a non-thermal method for enhancing the functional characteristics and digestibility of CPI. In this study, the reactive oxygen and nitrogen species generated by the APPJ treatment led to protein oxidation and increased carbonyl and di-tyrosine contents. At the same time, the secondary, tertiary and microstructural structures of CPI were changed. The solubility, water holding capacity, fat absorption capacity, emulsifying capacity and foaming capacity of CPI were significantly improved after 30 s APPJ treatment, and a higher storage modulus in rheology was observed. Additionally, it was observed that the in vitro protein digestibility (IVPD) of APPJ-treated CPI increased significantly from 44.85 ± 0.6 % to 50.2 ± 0.59 % following in vitro simulated gastric and intestinal digestion, marking a noteworthy improvement of 11.93 %. These findings indicate that APPJ processing can enhance the functional and digestive properties of CPI through structural modification and expand its potential applications within the food industry.


Assuntos
Cicer , Proteínas de Soja , Solubilidade , Água/química , Pressão Atmosférica
17.
Nat Commun ; 14(1): 7885, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38036495

RESUMO

Recent studies have reported worldwide vegetation suppression in response to increasing atmospheric vapor pressure deficit (VPD). Here, we integrate multisource datasets to show that increasing VPD caused by warming alone does not suppress vegetation growth in northern peatlands. A site-level manipulation experiment and a multiple-site synthesis find a neutral impact of rising VPD on vegetation growth; regional analysis manifests a strong declining gradient of VPD suppression impacts from sparsely distributed peatland to densely distributed peatland. The major mechanism adopted by plants in response to rising VPD is the "open" water-use strategy, where stomatal regulation is relaxed to maximize carbon uptake. These unique surface characteristics evolve in the wet soil‒air environment in the northern peatlands. The neutral VPD impacts observed in northern peatlands contrast with the vegetation suppression reported in global nonpeatland areas under rising VPD caused by concurrent warming and decreasing relative humidity, suggesting model improvement for representing VPD impacts in northern peatlands remains necessary.


Assuntos
Gases , Plantas , Pressão de Vapor , Pressão Atmosférica , Carbono
18.
J Am Soc Mass Spectrom ; 34(11): 2469-2480, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37843012

RESUMO

Matrix-assisted laser desorption/ionization (MALDI) mass spectrometry imaging (MSI) has become an important tool for skin analysis, as it allows the simultaneous detection and localization of diverse molecular species within a sample. The use of in vivo and ex vivo human skin models is costly and presents ethical issues; therefore, reconstructed human epidermis (RHE) models, which mimic the upper part of native human skin, represent a suitable alternative to investigate adverse effects of chemicals applied to the skin. However, there are few publications investigating the feasibility of using MALDI MSI on RHE models. Therefore, the aim of this study was to investigate the effect of sample preparation techniques, i.e., substrate, sample thickness, washing, and matrix recrystallization, on the quality of MALDI MSI for lipids analysis of the SkinEthic RHE model. Images were generated using an atmospheric pressure MALDI source coupled to a high-resolution mass spectrometer with a pixel size of 5 µm. Masses detected in a defined region of interest were analyzed and annotated using the LipostarMSI platform. The results indicated that the combination of (1) coated metallic substrates, such as APTES-coated stainless-steel plates, (2) tissue sections of 6 µm thickness, and (3) aqueous washing before HCCA matrix spraying (without recrystallization), resulted in images with a significant signal intensity as well as numerous m/z values. This refined methodology using AP-MALDI coupled to a high-resolution mass spectrometer should improve the current sample preparation workflow to evaluate changes in skin composition after application of dermatocosmetics.


Assuntos
Pressão Atmosférica , Técnicas Histológicas , Humanos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Lipídeos/análise , Epiderme/química
19.
J Agric Food Chem ; 71(37): 13899-13905, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37677086

RESUMO

Detecting bovine tuberculosis (bTB) primarily relies on the tuberculin skin test, requiring two separate animal handling events with a period of incubation time (normally 3 days) between them. Here, we present the use of liquid atmospheric pressure (LAP)-MALDI for the identification of bTB infection, employing a three-class prediction model that was obtained by supervised linear discriminant analysis (LDA) and tested with bovine mastitis samples as disease-positive controls. Noninvasive collection of nasal swabs was used to collect samples, which were subsequently subjected to a short (<4 h) sample preparation method. Cross-validation of the three-class LDA model from the processed nasal swabs provided a sensitivity of 75.0% and specificity of 90.1%, with an overall classification accuracy of 85.7%. These values are comparable to those for the skin test, showing that LAP-MALDI MS has the potential to provide an alternative single-visit diagnostic platform that can detect bTB within the same day of sampling.


Assuntos
Tuberculose Bovina , Animais , Feminino , Bovinos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Tuberculose Bovina/diagnóstico , Pressão Atmosférica , Biomarcadores , Análise Discriminante
20.
Molecules ; 28(17)2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37687137

RESUMO

Perception of flavor is a dynamic process during which the concentration of aroma molecules at the olfactory epithelium varies with time as they are released progressively from the food in the mouth during consumption. The release kinetics depends on the food matrix itself but also on food oral processing, such as mastication behavior and food bolus formation with saliva, for which huge inter-individual variations exist due to physiological differences. Sensory methods such as time intensity (TI) or the more-recent methods temporal dominance of sensations (TDS) and temporal check-all-that-apply (TCATA) are used to account for the dynamic and time-related aspects of flavor perception. Direct injection mass spectrometry (DIMS) techniques that measure in real time aroma compounds directly in the nose (nosespace), aimed at obtaining data that reflect the pattern of aroma release in real time during food consumption and supposed to be representative of perception, have been developed over the last 25 years. Examples obtained with MS operated in chemical ionization mode at atmospheric or sub-atmospheric pressure (atmospheric pressure chemical ionization APCI or proton-transfer reaction PTR) are given, with emphases on studies conducted with simultaneous dynamic sensory evaluation. Inter-individual variations in terms of aroma release and their relevance for understanding flavor perception are discussed as well as the evidenced cross-modal interactions.


Assuntos
Líquidos Corporais , Odorantes , Pressão Atmosférica , Face , Percepção
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