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1.
Trauma Case Rep ; 49: 100975, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38130411

ABSTRACT

Penetrating trauma is usually divided into stab and gunshot wounds (GSW). When considering GSW, the initial assessment involves the identification of all the wounds, to understand the projectile's trajectory as well as to determine which anatomic structures might have been damaged [1]. Rarely, the projectile might not leave the victim's body and embolize to a different region through large blood vessels. Known as Missile Embolism (ME), this uncommon complication can compromise multiple body segments, resulting in severe injuries, whether it occurs through an artery or a vein, such as pulmonary embolism, cardiac-valve incompetence, limb-threatening ischemia, coronary infarct, and stroke [2,3]. This is a case report of an 18-year-old male patient who suffered a gunshot wound and was submitted to an exploratory laparotomy which identified a laceration of the inferior vena cava. Further exams concluded that the bullet was embolized to the right hepatic vein. ME treatment will depend mostly on the bullet's placement; if located in the left circulation or arterial vessels, retrieval is the preferred treatment. It can be executed through surgical exploration or endovascular procedure [3,4,8] Venous ME has several treatment options, including conservative management if the patient remains asymptomatic [[3], [4], [5], [6], [7]]. Cases of paradoxical embolization might be managed as arterial ME [3,4].

2.
Science ; 371(6532): 931-936, 2021 02 26.
Article in English | MEDLINE | ID: mdl-33632843

ABSTRACT

Seafloor geophysical instrumentation is challenging to deploy and maintain but critical for studying submarine earthquakes and Earth's interior. Emerging fiber-optic sensing technologies that can leverage submarine telecommunication cables present an opportunity to fill the data gap. We successfully sensed seismic and water waves over a 10,000-kilometer-long submarine cable connecting Los Angeles, California, and Valparaiso, Chile, by monitoring the polarization of regular optical telecommunication channels. We detected multiple moderate-to-large earthquakes along the cable in the 10-millihertz to 5-hertz band. We also recorded pressure signals from ocean swells in the primary microseism band, implying the potential for tsunami sensing. Our method, because it does not require specialized equipment, laser sources, or dedicated fibers, is highly scalable for converting global submarine cables into continuous real-time earthquake and tsunami observatories.

3.
Microsyst Nanoeng ; 5: 55, 2019.
Article in English | MEDLINE | ID: mdl-31700673

ABSTRACT

Single-cell profiling provides insights into cellular behaviour that macroscale cell cultures and bulk measurements cannot reveal. In the context of personalized cancer treatment, the profiling of individual tumour cells may lead to higher success rates for therapies by rapidly selecting the most efficacious drugs. Currently, genomic analysis at the single-cell level is available through highly sensitive sequencing approaches. However, the identification and quantification of intracellular or secreted proteins or metabolites remains challenging. Here, we introduce a microfluidic method that facilitates capture, automated data acquisition and the multiplexed quantification of proteins from individual cells. The microfluidic platform comprises 1026 chambers with a volume of 152 pL each, in which single cells and barcoded beads are co-immobilized. We demonstrated multiplexed single-cell protein quantification with three different mammalian cell lines, including two model breast cancer cell lines. We established on-chip immunoassays for glyceraldehyde-3-phosphate dehydrogenase (GAPDH), galectin-3 (Gal-3) and galectin-3 binding protein (Gal-3bp) with detection limits as low as 7.0 × 104, 2.3 × 105 and 1.8 × 103 molecules per cell, respectively. The three investigated cell types had high cytosolic levels of GAPDH and could be clearly differentiated by their expression levels of Gal-3 and Gal-3bp, which are important factors that contribute to cancer metastasis. Because it employed commercially available barcoded beads for this study, our platform could be easily used for the single-cell protein profiling of several hundred different targets. Moreover, this versatile method is applicable to the analysis of bacteria, yeast and mammalian cells and nanometre-sized lipid vesicles.

4.
Dalton Trans ; 47(31): 10759-10766, 2018 Aug 21.
Article in English | MEDLINE | ID: mdl-29978162

ABSTRACT

Transition metal carbodiimides MNCN (M = Co, Ni, Co0.9Ni0.1, Mn and Cu), were studied by simultaneous operando Raman and X-ray absorption spectroscopy (XAS) with focus on surface oxide detection during electrocatalytic water oxidation. As a proof of concept, easily modifiable screen-printed electrodes were used in this unified operando synchrotron setup for a trade-off between convenience of electrochemical anodization and spectroscopic data acquisition. Monitoring of chemical and structural transformations at the electrode surface during initial anodic electrode polarization shows stability for MNCN with M = Co, Ni, Co0.9Ni0.1 and Mn. While MnNCN is inactive, CoNCN emerges as the most active representative of the series. CuNCN displays pronounced side reactions and the formation of a surface copper oxide layer leading to lower current density attributed to water oxidation, as evident from an irreversible variation of the CuNCN redox behaviour in rotating ring-disc voltammetry. Furthermore, the accompanying structural and vibrational spectroscopy properties of the different MNCN compounds were explored with complementary ex situ analytical methods.

5.
Anal Chem ; 90(15): 9234-9240, 2018 08 07.
Article in English | MEDLINE | ID: mdl-29963853

ABSTRACT

Nanoscale depth profiling analysis of a CoNCN-coated electrode for water oxidation catalysis was carried out using table-top extreme ultraviolet (XUV) laser ablation time-of-flight mass spectrometry. The self-developed laser operates at λ = 46.9 nm and represents factor of 4 reduction in wavelength with respect to the 193 nm excimer laser. The reduction of the wavelength is an alternative approach to the reduction of the pulse duration, to enhance the ablation characteristics and obtain smaller quasi-nondestructive ablation pits. Such a XUV-laser ablation method allowed distinguishing different composite components of the catalyst-Nafion blend, used to modify a screen-printed carbon electrode surface. Chemical information was extracted by fragment assignment and relative amplitude analysis of the mass spectrometry peaks. Pure Nafion and the exposed carbon substrate were compared as references. Material specific fragments were clearly identified by the detected nonoverlapping mass-to-charge peaks of Nafion and CoNCN. Three dimensional mapping of relevant mass peak amplitudes was used to determine the lateral distribution and to generate depth profiles from consecutive laser pulses. Evaluating the profiles of pristine electrodes gave insight into fragmentation behavior of the catalyst in a functional ionomer matrix and comparison of post-catalytic electrodes revealed spots of thin localized Co residues.

6.
Acta sci., Biol. sci ; 39(2): 243-249, abr.- jun. 2017. tab, ilus
Article in English | LILACS | ID: biblio-846870

ABSTRACT

Germination of diaspores and the seedling structure of Ruprechtia laxiflora Meissn. (Polygonaceae) which is a secondary species frequent in forest remnants are described. Seedlings were embedded in hydroxymethacrylate and sectioned in a rotary microtome according to usual techniques in plant anatomy. For bioassays of germination, the experimental design was completely randomized in a 3x2 bifactorial arrangement, corresponding to three temperatures (20, 25 and 30°C) and two light conditions (photoperiod and continuous darkness) for the diaspores newly harvested and in a 4x2 bifactorial arrangement, corresponding to four temperatures (15, 20, 25 and 30°C) and two light conditions (photoperiod and continuous darkness) for diaspores analyzed after storage. There was no interaction between the factors light condition and temperature for germination parameters analyzed. However, the temperature affected the germination and diaspores maintained at 25°C showed a shorter mean time and higher germination speed index. Seedlings are phanerocotylar and epigeal with tetrarch root, intermediate-low type of root-stem transition and trilacunar cotyledonary node.


Foram descritas a germinação de diásporos e a estrutura de plântulas de Ruprechtia laxiflora Meissn. (Polygonaceae), espécie secundária frequente em remanescentes florestais. As plântulas foram emblocadas em historresina e secionadas em micrótomo de rotação, de acordo com técnicas usuais em anatomia vegetal. Para os bioensaios de germinação, o delineamento experimental utilizado foi inteiramente casualizado em um esquema fatorial 3x2, correspondendo a três temperaturas (20, 25 e 30°C) e duas condições de luz (fotoperíodo e escuro contínuo) para os diásporos recém coletados e em esquema fatorial 4x2, correspondendo a quatro temperaturas (15, 20, 25 e 30°C) e duas condições de luz (fotoperíodo e escuro contínuo) para os diásporos analisados após armazenamento. Não houve interação entre os fatores condição de luz e temperatura para os parâmetros de germinação analisados. No entanto, o fator temperatura afetou a germinação e os diásporos mantidos sob 25°C apresentaram menor tempo médio e maior índice de velocidade de germinação. As plântulas são fanerocotiledonares e epigeias, com raiz tetrarca, tipo intermediário-baixo de zona de transição raiz-caule e nó cotiledonar trilacunar.


Subject(s)
Germination , Polygonaceae , Seedlings
7.
Acta sci., Biol. sci ; 37(4): 505-509, Oct.-Dec. 2015. tab, ilus
Article in English | LILACS | ID: biblio-875969

ABSTRACT

Studies on seed structure of Asteraceae have received little attention of botanists. Seed structure in Asteraceae is analyzed to evaluate the usefulness of characters in the separation of species through the analysis of nine weedy species. Seeds originate from anatropous, unitegmic and tenuinucellate ovules. The partial collapse of the developing seed coat is a common characteristic in the Asteraceae species studied. The testa consists of crushed and thin-walled cells in almost all of the species studied herein, except for Elephantopus mollis and Parthenium hysterophorus, which showed exotesta cells with U-shaped thickening. The analysis revealed high uniformity in seed characters.


Estudos da estrutura da semente de Asteraceae receberam pouca atenção de botânicos. A estrutura da semente de Asteraceae é examinada com a finalidade de avaliar a utilidade dos caracteres na separação de espécies, mediante a análise de nove espécies de plantas daninhas. As sementes são originárias de óvulos anátropos, unitegumentado e tenuinucelados. O colapso parcial do revestimento da semente em desenvolvimento é uma característica comum nas espécies estudadas de Asteraceae. A testa é composta por células colapsadas e de paredes finas em quase todas as espécies estudadas, com exceção de Elephantopus mollis e Parthenium hysterophorus, que demonstraram células da exotesta com espessamento em U. A análise revelou uma grande quantidade de uniformidade dos caracteres estudados das sementes.


Subject(s)
Asteraceae , Embryonic Structures , Endosperm , Ovum
8.
Chempluschem ; 80(9): 1389-1398, 2015 Sep.
Article in English | MEDLINE | ID: mdl-31973363

ABSTRACT

In search of structure-activity relationships for polyoxometalate (POM)-based water reduction catalysts, nickel-monosubstituted Keggin-type POMs ([Ni(H2 O)XW11 O39 ]n- ; XP, Si, Ge) were compared with respect to their activity in photochemical hydrogen evolution. The title compound series was characterized by single-crystal X-ray diffraction methods and a wide range of spectroscopic and electrochemical techniques. Nickel substitution was identified as a crucial feature for catalytic activity through comparison with nickel-free reference POMs. Furthermore, turnover number (TON) and turnover frequency strongly depended on the heteroatom X, and the highest TON among the series was recorded for [Ni(H2 O)GeW11 O39 ]6- . Photochemical hydrogen evolution activity was compared with redox and onset potentials obtained from electrochemical analyses. Furthermore, activity trends were correlated with electronic structure properties derived from density functional theory calculations.

9.
Phys Chem Chem Phys ; 13(30): 13759-64, 2011 Aug 14.
Article in English | MEDLINE | ID: mdl-21720644

ABSTRACT

Signal Amplification by Reversible-Exchange (SABRE) is a method of hyperpolarizing substrates by polarization transfer from para-hydrogen without hydrogenation. Here, we demonstrate that this method can be applied to hyperpolarize small amounts of all proteinogenic amino acids and some chosen peptides down to the nanomole regime and can be detected in a single scan in low-magnetic fields down to 0.25 mT (10 kHz proton frequency). An outstanding feature is that depending on the chemical state of the used catalyst and the investigated amino acid or peptide, hyperpolarized hydrogen-deuterium gas is formed, which was detected with (1)H and (2)H NMR spectroscopy at low magnetic fields of B(0) = 3.9 mT (166 kHz proton frequency) and 3.2 mT (20 kHz deuterium frequency).


Subject(s)
Amino Acids/chemistry , Hydrogen/chemistry , Peptides/chemistry , Deuterium/chemistry , Gases/chemistry , Hydrogenation , Magnetic Resonance Spectroscopy
10.
Analyst ; 136(8): 1566-8, 2011 Apr 21.
Article in English | MEDLINE | ID: mdl-21331396

ABSTRACT

Advances with para-hydrogen induced polarization open up new fields of applications for portable low-field NMR. Here we report the possibility of tracing drugs down to the micromolar regime. We could selectively polarize nicotine quantities similar to those found in one cigarette. Also less than 1 mg of harmine, a drug used for treatment of Parkinson's disease, and morphine extracted from an opium solution were detectable after polarization with para-hydrogen in single-scan (1)H-experiments. Moreover, we demonstrate the possibility to selectively enhance and detect the (1)H-signal of drug molecules with PHIP in proton rich standard solutions that would otherwise mask the (1)H NMR signal of the drug.


Subject(s)
Drug Residues/analysis , Magnetic Resonance Spectroscopy/methods , Harmine/analysis , Hydrogen/chemistry , Morphine/analysis , Nicotine/analysis , Opium/chemistry , Nicotiana/chemistry
11.
Rev Soc Bras Med Trop ; 35(4): 283-91, 2002.
Article in English | MEDLINE | ID: mdl-12170321

ABSTRACT

Although acute respiratory infections (ARIs) are a major cause of child morbidity and mortality in Southern Brazil, little information is available on their seasonality and viral etiology. This study was conducted on children under 5 years of age with ARI to assess viral etiology in the State of Rio Grande do Sul, from 1990 to 1992. A total of 862 nasopharyngeal secretion (NPS) samples were tested using indirect immunofluorescence. The results showed that 316 (36.6%) NPS samples were positive: 26.2% for RSV, 6% for adenovirus, 1.7% for influenza viruses, 1.5% for parainfluenza viruses, and 1.2% for mixed infection. The mean viral prevalence rates in out-patient services, emergency wards, and in-patient hospital wards were 26.7%, 53% and 42.3%, respectively. Respiratory syncytial virus (RSV) and adenovirus accounted for 91.4 % of the viral diagnoses. RSV was more frequent in children under one year of age at the three levels of health care and was prevalent in infants under six months. Adenovirus was the most prevalent pathogen in hospitalized children, in 1992. Influenza A virus showed an increased prevalence with age among out-patient children. This study shows the annual occurrence of viral respiratory infections in the coldest months, with a significant annual variation in the frequency of RSV infection.


Subject(s)
Adenovirus Infections, Human/complications , Respiratory Syncytial Virus Infections/complications , Respiratory Tract Infections/virology , Acute Disease , Adenovirus Infections, Human/epidemiology , Brazil/epidemiology , Child, Preschool , Female , Humans , Infant , Infant, Newborn , Male , Prevalence , Respiratory Syncytial Virus Infections/epidemiology , Respiratory Tract Infections/epidemiology
12.
Rev. Soc. Bras. Med. Trop ; 35(4): 283-291, jul.-aug. 2002.
Article in English | LILACS | ID: lil-331755

ABSTRACT

Although acute respiratory infections (ARIs) are a major cause of child morbidity and mortality in Southern Brazil, little information is available on their seasonality and viral etiology. This study was conducted on children under 5 years of age with ARI to assess viral etiology in the State of Rio Grande do Sul, from 1990 to 1992. A total of 862 nasopharyngeal secretion (NPS) samples were tested using indirect immunofluorescence. The results showed that 316 (36.6) NPS samples were positive: 26.2 for RSV, 6 for adenovirus, 1.7 for influenza viruses, 1.5 for parainfluenza viruses, and 1.2 for mixed infection. The mean viral prevalence rates in out-patient services, emergency wards, and in-patient hospital wards were 26.7, 53 and 42.3, respectively. Respiratory syncytial virus (RSV) and adenovirus accounted for 91.4 of the viral diagnoses. RSV was more frequent in children under one year of age at the three levels of health care and was prevalent in infants under six months. Adenovirus was the most prevalent pathogen in hospitalized children, in 1992. Influenza A virus showed an increased prevalence with age among out-patient children. This study shows the annual occurrence of viral respiratory infections in the coldest months, with a significant annual variation in the frequency of RSV infection.


Subject(s)
Humans , Male , Female , Infant, Newborn , Infant , Child, Preschool , Adenovirus Infections, Human , Respiratory Syncytial Virus Infections/complications , Respiratory Tract Infections/virology , Acute Disease , Adenovirus Infections, Human , Brazil , Respiratory Syncytial Virus Infections/epidemiology , Respiratory Tract Infections/epidemiology , Prevalence
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