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1.
Sensors (Basel) ; 23(17)2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37688010

RESUMO

We further simplify the most 'user-friendly' potentiometric sensor for waterborne analytes, the 'extended-gate field effect transistor' (EGFET). This is accomplished using a 'bridge' design, that links two separate water pools, a 'control gate' (CG) pool and a 'floating gate' (FG) pool, by a bridge filled with agar-agar hydrogel. We show electric communication between electrodes in the pools across the gel bridge to the gate of an LND150 FET. When loading the gel bridge with a sorbent that is known to act as a sensitiser for Cu2+ water pollution, namely, the ion exchanging zeolite 'clinoptilolite', the bridged EGFET acts as a potentiometric sensor to waterborne Cu2+. We then introduce novel sensitisers into the gel bridge, the commercially available resins PurometTM MTS9140 and MTS9200, which are sorbents for the extraction of mercury (Hg2+) pollution from water. We find a response of the bridged EGFET to Hg2+ water pollution, setting a template for the rapid screening of ion exchange resins that are readily available for a wide range of harmful (or precious) metal ions. We fit the potentiometric sensor response vs. pollutant concentration characteristics to the Langmuir-Freundlich (LF) model which is discussed in context with other ion-sensor characteristics.

2.
Antibiotics (Basel) ; 11(5)2022 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-35625227

RESUMO

Edible films and essential oil (EO) systems have the potency to enhance the microbial quality and shelf life of food. This investigation aimed to evaluate the efficacy of chitosan films including essential oils against spoilage bacteria and foodborne pathogens associated with meat. Antimicrobial activity (in vitro and in vivo) of chitosan films (CH) incorporated with oregano oil (OO) and thyme oil (TO) at 0.5 and 1% was done against spoilage bacteria and foodborne pathogens, compared to the control sample and CH alone. Preliminary experiments (in vitro) showed that the 1% OO and TO were more active against Staphylococcus aureus compared to Escherichia coli O157:H7 and Salmonella Typhimurium. In in vivo studies, CH containing OO and TO effectively inhibited the three foodborne pathogens and spoilage bacteria linked with packed beef meat which was kept at 4 °C/30 days compared to the control. The total phenolic content of the EOs was 201.52 mg GAE L-1 in thyme and 187.64 mg GAE L-1 in oregano. The antioxidant activity of thyme oil was higher than oregano oil. The results demonstrated that the shelf life of meat including CH with EOs was prolonged ~10 days compared to CH alone. Additionally, CH-OO and CH-TO have improved the sensory acceptability until 25 days, compared to the control. Results revealed that edible films made of chitosan and containing EOs improved the quality parameters and safety attributes of refrigerated or fresh meat.

3.
J Nucl Med Technol ; 2021 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-34876477

RESUMO

Background: While normal ranges for 99mTc thyroid percentage uptake vary, the seemingly intuitive evaluation of thyroid function does not reflect the complexity of thyroid pathology and biochemical status. The emergence of artificial intelligence (AI) in nuclear medicine has driven problem solving associated with logic and reasoning that warrant re-examination of established benchmarks in thyroid functional assessment. Methods: There were 123 patients retrospectively analysed in the study sample comparing scintigraphic findings to grounded truth established through biochemistry status. Conventional statistical approaches were used in conjunction with an artificial neural network (ANN) to determine predictors of thyroid function from data features. A convolutional neural network (CNN) was also used to extract features from the input tensor (images). Results: Analysis was confounded by sub-clinical hyperthyroidism, primary hypothyroidism, sub-clinical hypothyroidism and T3 toxicosis. Binary accuracy for identifying hyperthyroidism was highest for thyroid uptake classification using a threshold of 4.5% (82.6%), followed by pooled physician 6interpretation with the aid of uptake values (82.3%). Visual evaluation without quantitative values reduced accuracy to 61.0% for pooled physician determinations and 61.4% classifying on the basis of thyroid gland intensity relative to salivary glands. The machine learning (ML) algorithm produced 84.6% accuracy, however, this included biochemistry features not available to the semantic analysis. The deep learning (DL) algorithm had an accuracy of 80.5% based on image inputs alone. Conclusion: Thyroid scintigraphy is useful in identifying hyperthyroid patients suitable for radioiodine therapy when using an appropriately validated cut-off for the patient population (4.5% in this population). ML ANN algorithms can be developed to improve accuracy as second readers systems when biochemistry results are available. DL CNN algorithms can be developed to improve accuracy in the absence of biochemistry results. ML and DL do not displace the role of the physician in thyroid scintigraphy but could be used as second reader systems to minimize errors and increase confidence.

4.
Sci Rep ; 11(1): 8950, 2021 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-33903607

RESUMO

Reconstruction of a critical-sized osseous defect is challenging in maxillofacial surgery. Despite novel treatments and advances in supportive therapies, severe complications including infection, nonunion, and malunion can still occur. Here, we aimed to assess the use of a beta-tricalcium phosphate (ß-TCP) scaffold loaded with high mobility group box-1 protein (HMGB-1) as a novel critical-sized bone defect treatment in rabbits. The study was performed on 15 specific pathogen-free New Zealand rabbits divided into three groups: Group A had an osseous defect filled with a ß-TCP scaffold loaded with phosphate-buffered saline (PBS) (100 µL/scaffold), the defect in group B was filled with recombinant human bone morphogenetic protein 2 (rhBMP-2) (10 µg/100 µL), and the defect in group C was loaded with HMGB-1 (10 µg/100 µL). Micro-computed tomography (CT) examination demonstrated that group C (HMGB-1) showed the highest new bone volume ratio, with a mean value of 66.5%, followed by the group B (rhBMP-2) (31.0%), and group A (Control) (7.1%). Histological examination of the HMGB-1 treated group showed a vast area covered by lamellar and woven bone surrounding the ß-TCP granule remnants. These results suggest that HMGB-1 could be an effective alternative molecule for bone regeneration in critical-sized mandibular bone defects.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Proteína HMGB1/farmacologia , Mandíbula/metabolismo , Traumatismos Mandibulares/tratamento farmacológico , Animais , Fosfatos de Cálcio/farmacologia , Humanos , Masculino , Mandíbula/patologia , Traumatismos Mandibulares/mortalidade , Traumatismos Mandibulares/patologia , Coelhos
5.
Mymensingh Med J ; 16(2): 214-6, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17703162

RESUMO

Osteosarcoma of clavicle is extremely rare. Improved survival in patients with osteosarcomas has been associated with recent advances in imaging techniques, histopathological methods, surgery and chemotherapy. In most cases the diagnosis can be made with confidence on the x-ray appearance. Other imaging studies like- radioisotope scans may show up-skip lesions, computed tomography (CT) and magnetic resonance imaging (MRI) show the extend of the tumour. Incisional biopsy or excisional biopsy is carried out after careful clinical study and proper investigations. A 30 years old cultivator with a late case of primary osteosarcoma of clavicle was treated with pre-operative and post-operative chemotherapy and was managed with surgical excision of tumor with limb sparing. The patient was clinically disease free for about 08 (eight) months. Then the patient developed recurrences and died 11 (eleven) months after operation.


Assuntos
Neoplasias Ósseas/cirurgia , Clavícula , Salvamento de Membro , Osteossarcoma/cirurgia , Adulto , Humanos , Masculino
6.
Biotechniques ; 32(2): 338-40, 342, 344, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11848411

RESUMO

The comprehensive analysis and visualization of data extracted from cDNA microarrays can be a time-consuming and error-prone process that becomes increasingly tedious with increased number of gene elements on a particular microarray. With the increasingly large number of gene elements on today's microarrays, analysis tools must be developed to meet this challenge. Here, we present MarC-V, a Microsoft Excel spreadsheet tool with Visual Basic macros to automate much of the visualization and calculation involved in the analysis process while providing the familiarity and flexibility of Excel. Automated features of this tool include (i) lower-bound thresholding, (ii) data normalization, (iii) generation of ratio frequency distribution plots, (iv) generation of scatter plots color-coded by expression level, (v) ratio scoring based on intensity measurements, (vi) filtering of data based on expression level or specific gene interests, and (vii) exporting data for subsequent multi-array analysis. MarC-V also has an importing function included for GenePix results (GPR) raw data files.


Assuntos
Análise de Sequência com Séries de Oligonucleotídeos/métodos , Software , DNA Complementar
8.
J Clin Invest ; 100(2): 398-403, 1997 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-9218517

RESUMO

Lowering of the elevated plasma FFA concentration in 18- 24-h fasted rats with nicotinic acid (NA) caused complete ablation of subsequent glucose-stimulated insulin secretion (GSIS). Although the effect of NA was reversed when the fasting level of total FFA was maintained by coinfusion of soybean oil or lard oil (plus heparin), the more saturated animal fat proved to be far more potent in enhancing GSIS. We therefore examined the influence of individual fatty acids on insulin secretion in the perfused rat pancreas. When present in the perfusion fluid at 0.5 mM (in the context of 1% albumin), the fold stimulation of insulin release from the fasted pancreas in response to 12.5 mM glucose was as follows: octanoate (C8:0), 3.4; linoleate (C18:2 cis/cis), 5.3; oleate (C18:1 cis), 9.4; palmitate (C16:0), 16. 2; and stearate (C18:0), 21.0. The equivalent value for palmitoleate (C16:1 cis) was 3.1. A cis--> trans switch of the double bond in the C16:1 and C18:1 fatty acids had only a modest, if any, impact on their potency. A similar profile emerged with regard to basal insulin secretion (3 mM glucose). When a subset of these fatty acids was tested in pancreases from fed animals, the same rank order of effectiveness at both basal and stimulatory levels of glucose was seen. The findings reaffirm the essentiality of an elevated plasma FFA concentration for GSIS in the fasted rat. They also show, however, that the insulinotropic effect of individual fatty acids spans a remarkably broad range, increasing and decreasing dramatically with chain length and degree of unsaturation, respectively. Thus, for any given level of glucose, insulin secretion will be influenced greatly not only by the combined concentration of all circulating (unbound) FFA, but also by the makeup of this FFA pool. Both factors will likely be important considerations in understanding the complex interplay between the nature of dietary fat and whole body insulin, glucose, and lipid dynamics.


Assuntos
Gorduras na Dieta/farmacologia , Ácidos Graxos/farmacologia , Insulina/metabolismo , Niacina/farmacologia , Animais , Gorduras na Dieta/administração & dosagem , Gorduras na Dieta/metabolismo , Emulsões Gordurosas Intravenosas/administração & dosagem , Emulsões Gordurosas Intravenosas/farmacologia , Ácidos Graxos/sangue , Ácidos Graxos/química , Ácidos Graxos Insaturados/farmacologia , Glucose/farmacologia , Insulina/sangue , Masculino , Pâncreas/metabolismo , Perfusão , Ratos , Ratos Sprague-Dawley , Óleo de Soja/administração & dosagem , Óleo de Soja/farmacologia
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