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The demand for methods and technologies capable of rapid, inexpensive and continuous monitoring of health status or exposure to environmental pollutants persists. In this work, the development of novel surface-enhanced Raman spectroscopy (SERS) substrates from metal-coated silk fabric, known as zari, presents the potential for SERS substrates to be incorporated into clothing and other textiles for the routine monitoring of important analytes, such as disease biomarkers or environmental pollutants. Characterization of the zari fabric was completed using scanning electron microscopy, energy dispersive X-ray analysis and Raman spectroscopy. Silver nanoparticles (AgNPs) were prepared, characterized by transmission electron microscopy and UV-vis spectroscopy, and used to treat fabric samples by incubation, drop-coating and in situ synthesis. The quality of the treated fabric was evaluated by collecting the SERS signal of 4,4'-bipyridine on these substrates. When AgNPs were drop-coated on the fabric, sensitive and reproducible substrates were obtained. Adenine was selected as a second probe molecule, because it dominates the SERS signal of DNA, which is an important class of disease biomarker, particularly for pathogens such as Plasmodium spp. and Mycobacterium tuberculosis. Excellent signal enhancement could be achieved on these affordable substrates, suggesting that the developed fabric chips have the potential for expanding the use of SERS as a diagnostic and environmental monitoring tool for application in wearable sensor technologies.
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DNA Bacteriano/análise , Nanopartículas Metálicas/química , Seda/análise , Prata/química , Análise Espectral Raman/métodos , Têxteis/análise , Poluentes Ambientais/análise , Microscopia Eletrônica de Varredura/métodos , Microscopia Eletrônica de Transmissão/métodos , Piridinas/química , Seda/química , Seda/economia , Propriedades de SuperfícieRESUMO
OBJECT The objective of this study was to provide a technique that could be used in the preoperative period to facilitate the surgical exploration of peripheral nerve pathology. METHODS The authors describe a technique in which 1) ultrasonography is used in the immediate preoperative period to identify target peripheral nerves, 2) an ultrasound-guided needle electrode is used to stimulate peripheral nerves to confirm their position, and then 3) a methylene blue (MB) injection is performed to mark the peripheral nerve pathology to facilitate surgical exploration. RESULTS A cohort of 13 patients with varying indications for peripheral nerve surgery is presented in which ultrasound guidance, stimulation, and MB were used to localize and create a road map for surgeries. CONCLUSIONS Preoperative ultrasound-guided MB administration is a promising technique that peripheral nerve surgeons could use to plan and execute surgery.
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Azul de Metileno/metabolismo , Procedimentos Neurocirúrgicos/métodos , Doenças do Sistema Nervoso Periférico/diagnóstico por imagem , Doenças do Sistema Nervoso Periférico/cirurgia , Ultrassonografia de Intervenção/métodos , Adulto , Estudos de Coortes , Feminino , Humanos , Injeções Intradérmicas , Imageamento por Ressonância Magnética , Masculino , Azul de Metileno/administração & dosagem , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos/normas , Doenças do Sistema Nervoso Periférico/etiologia , Doenças do Sistema Nervoso Periférico/metabolismoRESUMO
We synthesized and characterized two isomeric microporous hydrocarbon ladder polymers from catalytic arene norbornene annulation (CANAL) of regioisomeric bis-norbornene fused spirobifluorenes, where the ladder chains are connected either through the same fluorene unit or across two different fluorene units in spirobifluorene. This pair of isomeric polymers was used to investigate the effect of ladder macromolecular structures on the microporosity and transport properties. Both polymers form mechanically intact films with thermal stability up to 480 °C and relatively high BET surface areas. The polymer formed from 2,7-dibromospirobifluorene showed higher BET surface area and higher gas permeability than the polymer from 2,2'-dibromospirobifluorene despite similar intersegmental spacing as indicated by X-ray scattering. The aging behavior for both polymers followed the same trend as the previously reported CANAL-fluorene polymers, with dramatically increased permselectivities over time, resulting in gas separation performance above the 2008 upper bounds for H2/CH4 and O2/N2.
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Background: Asymptomatic congenital pulmonary airway malformations (CPAMs) and congenital lobar emphysema (CLE) may safely be observed, though little is known about how many patients later require surgery. The management of these lesions remains controversial, as limited research exists on which patients later require surgery. Notably, there are few reported cases where patients become symptomatic and require definitive treatment beyond childhood. Case Description: We present the rare case of a 17-year-old female who developed dyspnea on exertion associated with pre-syncope, following diagnosis of a CPAM at birth. She had undergone surveillance until 2 years of age. The decision to proceed with a left upper lobectomy via thoracotomy was made, for treatment of her symptoms. During the surgery, one lung ventilation suggested that oxygenation had likely limited to the patient's healthy lung, prior to intervention. The surgery was uncomplicated, and her recovery was uneventful. Pathology revealed CLE. Conclusions: This case highlights that congenital lung malformations should remain in the differential diagnosis of patients presenting in adolescence or adulthood with new onset respiratory symptoms. For patients with a history of untreated congenital lung pathology, it is important to consider the presence of adhesions and loss of domain in perioperative planning. This case also highlights the ongoing need for research on the prognostication of these lesions to better inform surveillance.
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An increased level of uric acid in urine and plasma is indicative of the development of preeclampsia, a hypertensive disorder that can occur during pregnancy. The preliminary steps towards developing a rapid tool for early diagnosis of preeclampsia using electrochemical SERS (E-SERS) for the detection of uric acid in urine are presented herein. Characterization of the uric acid species was completed using cyclic voltammetry, UV spectroscopy, Raman spectroscopy and electrochemical surface-enhanced Raman spectroscopy (E-SERS). E-SERS was capable of easily detecting uric acid directly at concentrations <1 mM in urine simulant, without the need for costly enzymes and bulky equipment, and thus demonstrates promise as a rapid point-of-care diagnostic tool for detection of early onset preeclampsia in developing nation settings.
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Técnicas Eletroquímicas , Pré-Eclâmpsia/diagnóstico , Análise Espectral Raman , Ácido Úrico/urina , Feminino , Humanos , Nanopartículas Metálicas/química , Gravidez , Prata/químicaRESUMO
Membranes have the potential to substantially reduce energy consumption of industrial chemical separations, but their implementation has been limited owing to a performance upper bound-the trade-off between permeability and selectivity. Although recent developments of highly permeable polymer membranes have advanced the upper bounds for various gas pairs, these polymers typically exhibit limited selectivity. We report a class of hydrocarbon ladder polymers that can achieve both high selectivity and high permeability in membrane separations for many industrially relevant gas mixtures. Additionally, their corresponding films exhibit desirable mechanical and thermal properties. Tuning of the ladder polymer backbone configuration was found to have a profound effect on separation performance and aging behavior.
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Undergraduate students in the biomedical sciences are often interested in future health-focused careers. This presents opportunities for instructors in genetics, molecular biology, and cancer biology to capture their attention using lab experiences built around clinically relevant data. As biomedical science in general becomes increasingly dependent on high-throughput data, well-established scientific databases such as The Cancer Genome Atlas (TCGA) have become publicly available tools for medically relevant inquiry. The best feature of this database is that it bridges the molecular features of cancer to human clinical outcomes-allowing students to see a direct connection between the molecular sciences and their future professions. We have developed and tested a learning module that leverages the power of TCGA datasets to engage students to use the data to generate and test hypotheses and to apply statistical tests to evaluate significance.