Time Of Flight
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2021 ◽  
Author(s):  
Yajun Fang ◽  
Shuhua Li ◽  
Chuanchen Zhang

The persistent proatlantal intersegmental artery is a rare variant of persistent carotid-vertebrobasilar anastomoses, especially their bilateral presence is rarer. We report a case of bilateral typeII persistent proatlantal intersegmental artery. The absence of bilateral vertebral arteries was incidentally noted on neck ultrasound examination. Subsequent time-of-flight MR angiography confirmed this. The bilateral typeIIpersistent proatlantal intersegmental artery arose from the cervical external carotid artery, penetrated the C1 transverse foramen, entered the skull via the foramen magnum, and joined the lower portion of the basilar artery.


2021 ◽  
pp. 96-101
Author(s):  
Maria Eduarda Campos Bezerra ◽  
Rosilma Melo ◽  
Francisco Montenegro

O índice da resistência antimicrobiana (RAM) cresce progressivamente no mundo e acaba limitando a eficácia de tratamento de doenças comuns, como a infecção do trato urinário (ITU). Além disso, na atualidade, a RAM é apontada como um dos principais problemas de saúde pública. Diante do exposto, o objetivo do presente estudo foi avaliar a resistência bacteriana frente aos antibióticos orais mais comumente utilizados para o tratamento das ITU em pacientes ambulatoriais, bem como a identificação das bactérias isoladas. Foi realizado um estudo observacional experimental com abordagem quantitativa no período de janeiro a maio de 2019, desenvolvido em um hospital privado de alta complexidade localizado na cidade do Recife, PE. Foram incluídas no estudo todas as uroculturas positivas de pacientes adultos atendidos no ambulatório do referido hospital, onde foi utilizado, para a identificação bacteriana, o equipamento MALDI – TOF (Matrix Associated Laser Desorption-Ionization – Time of Flight). Foram analisadas um total de 379 amostras positivas de uroculturas, das quais 16 (4,2%) representavam espécies sem interesse clínico, pois obtiveram uma porcentagem de frequência muito baixa, bem como 327 (86,3%) pertenciam a três espécies de bactérias Gram-negativas: Escherichia coli (72,8%), Klebsiella pneumoniae (16,2%) e Proteus mirabilis (11%). Enquanto nas 36 (9,5%) amostras foram identificadas duas espécies Gram-positivas: Staphylococcus saprophyticus (66,7%) e Enterococcus faecalis (33,3%).  Foi possível observar que o antibiótico oral com maior percentual de resistência foi o sulfametoxazol + trimetoprima com 24,5% seguido da ciprofloxacina com 22,1%, cefuroxima (16,7%), amoxicilina + clavulanato (13,0%) e nitrofurantoína (8,1%). De acordo com recomendação, é excluído o uso de antibióticos que apresentarem resistência acima de 20%, desta forma os únicos antibióticos por via oral que possui perfil terapêutico adequado para o tratamento empírico dos pacientes adultos com ITU na região do presente estudo são cefuroxima, amoxicilina + clavulanato e nitrofurantoína.  


2021 ◽  
Author(s):  
Cheick Oumar Guindo ◽  
Lynda Amir ◽  
Carine Couder ◽  
Michel Drancourt ◽  
Ghiles Grine

Methanogens, the archaea uniquely detoxifying fermentative hydrogen into methane in the digestive tract, are increasingly detected in pathology situations, rendering their rapid identification mandatory. We improved the experimental protocol to identify broth-cultured methanogens by matrix-assisted laser desorption time-of-flight mass spectrometry (MALDI-TOF-MS). A database incorporating 34 reference spectra derived from 16 methanogen reference strains representative of eight species, supported further identification of 21 Methanobrevibacter smithii and 14 Methanobrevibacter oralis isolates broth-cultured from human stool and oral fluid, respectively, with scores > 2. In addition, MALDI-TOF-MS differentiated five Methanobrevibacter smithii genotypes incorporated in the study. Data here reported found MALDI-TOF-MS as a first line identification method for methanogens recovered from microbiota and clinical samples.


2021 ◽  
pp. 1-26
Author(s):  
Manale Noun ◽  
Rayane Akoumeh ◽  
Imane Abbas

Abstract The potential of mass spectrometry imaging (MSI) has been demonstrated in cell and tissue research since 1970. MSI can reveal the spatial distribution of a wide range of atomic and molecular ions detected from biological sample surfaces, it is a powerful and valuable technique used to monitor and detect diverse chemical and biological compounds, such as drugs, lipids, proteins, and DNA. MSI techniques, notably matrix-assisted laser desorption/ionization time of flight (MALDI-TOF) and time of flight secondary ion mass spectrometry (TOF-SIMS), witnessed a dramatic upsurge in studying and investigating biological samples especially, cells and tissue sections. This advancement is attributed to the submicron lateral resolution, the high sensitivity, the good precision, and the accurate chemical specificity, which make these techniques suitable for decoding and understanding complex mechanisms of certain diseases, as well as monitoring the spatial distribution of specific elements, and compounds. While the application of both techniques for the analysis of cells and tissues is thoroughly discussed, a briefing of MALDI-TOF and TOF-SIMS basis and the adequate sampling before analysis are briefly covered. The importance of MALDI-TOF and TOF-SIMS as diagnostic tools and robust analytical techniques in the medicinal, pharmaceutical, and toxicology fields is highlighted through representative published studies.


2021 ◽  
Vol 42 ◽  
pp. 101207
Author(s):  
Aikaterini Liangou ◽  
Antonios Tasoglou ◽  
Heinz J. Huber ◽  
Christopher Wistrom ◽  
Kevin Brody ◽  
...  

Metabolites ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 793
Author(s):  
Jiyoung Shin ◽  
Junho Yang ◽  
Eunji Cha ◽  
Hyunsuk Kim ◽  
Yoonhyeung Lee ◽  
...  

Country-of-origin violations have occurred in which some merchants have fraudulently sold cheap Japanese yellowtail (Seriola quinqueradiata) by presenting them as domestic Korean products. There are many methods for determining the origins of marine organisms, such as molecular genetic methods and isotope analysis. However, this study aimed to develop a method for determining the origins of aquatic products using metabolite analysis technology. Ten yellowtail each from Korea and Japan were analyzed by capillary electrophoresis–time of flight/mass spectrometry (CETOF/MS). Hierarchical cluster analysis (HCA) and principal component analysis (PCA) results showed highly differing aspects between the Korean and Japanese samples. In the tricarboxylic acid (TCA) cycle, citric, malic, oxaloglutaric, and fumaric acids exhibited significant differences between Korean and Japanese yellowtail. Sixteen of the twenty essential amino acids analyzed as metabolites also differed significantly. All amino acids were involved in protein digestion, absorption, and metabolism. All 16 amino acid contents were higher in Japanese yellowtail than in Korean yellowtail, except for glutamine. The fasting period was found to be the biggest factor contributing to the difference in amino acid contents, in addition to environmental factors (including feeding habits). These significant differences indicated that metabolomics could be used to determine geographical origin.


2021 ◽  
Vol 11 (22) ◽  
pp. 10913
Author(s):  
Kaiwen Guo ◽  
Tianqu Zhai ◽  
Elton Pashollari ◽  
Christopher J. Varlamos ◽  
Aymaan Ahmed ◽  
...  

This study describes a contactless vital sign monitoring (CVSM) system capable of measuring heart rate (HR) and respiration rate (RR) using a low-power, indirect time-of-flight (ToF) camera. The system takes advantage of both the active infrared illumination as well as the additional depth information from the ToF camera to compensate for the motion-induced artifacts during the HR measurements. The depth information captures how the user is moving with respect to the camera and, therefore, can be used to differentiate where the intensity change in the raw signal is from the underlying heartbeat or motion. Moreover, from the depth information, the system can acquire respiration rate by directly measuring the motion of the chest wall during breathing. We also conducted a pilot human study using this system with 29 participants of different demographics such as age, gender, and skin color. Our study shows that with depth-based motion compensation, the success rate (system measurement within 10% of reference) of HR measurements increases to 75%, as compared to 35% when motion compensation is not used. The mean HR deviation from the reference also drops from 21 BPM to −6.25 BPM when we apply the depth-based motion compensation. In terms of the RR measurement, our system shows a mean deviation of 1.7 BPM from the reference measurement. The pilot human study shows the system performance is independent of skin color but weakly dependent on gender and age.


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