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1.
Sensors (Basel) ; 19(13)2019 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-31284580

RESUMO

With the growth of the internet of things (IoT), many challenges like information security and privacy, interoperability/standard, and regulatory and legal issues are arising. This work focused on the information security issue, which is one of the primary challenges faced by connected systems that needs to be resolved without impairing system behaviour. Information, which is made available on the Internet by the things, varies from insensitive information (e.g., readings from outdoor temperature sensors) to extremely sensitive information (e.g., video stream from a camera) and needs to be secured over the Internet. Things which utilise cameras as a source of information pertain to a subclass of the IoT called IoVT (internet of video things). This paper presents secured and unsecured video latency measurement results over the Internet for a marine ROV (remotely operated vehicle). A LabVIEW field programmable gate arrays (FPGAs)-based bump-in-the-wire (BITW) secure core is used to provide an AES (advanced encryption standard)-enabled security feature on the video stream of an IoVT node (ROV equipped with a live-feed camera). The designed LabVIEW-based software architecture provides an option to enable/disable the AES encryption for the video transmission. The latency effects of embedding encryption on the stream with real-time constraints are measured and presented. It is found that the encryption mechanism used does not greatly influence the video feedback performance of the observed IoVT node, which is critical for real-time secure video communication for ROV remote control and piloting. The video latency measurement results are taken using 128, 256 and 512 bytes block lengths of AES for both H.264 and MJPEG encoding schemes transmitted over both TCP and UDP transmission protocols. The latency measurement is performed in two scenarios (i.e., with matching equipment and different equipment on either end of the transmission).

2.
Sensors (Basel) ; 16(1)2016 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-26797620

RESUMO

Wireless sensor networks (WSNs) are being used to facilitate monitoring of patients in hospital and home environments. These systems consist of a variety of different components/sensors and many processes like clustering, routing, security, and self-organization. Routing is necessary for medical-based WSNs because it allows remote data delivery and it facilitates network scalability in large hospitals. However, routing entails several problems, mainly due to the open nature of wireless networks, and these need to be addressed. This paper looks at two of the problems that arise due to wireless routing between the nodes and access points of a medical WSN (for IoT use): black hole and selective forwarding (SF) attacks. A solution to the former can readily be provided through the use of cryptographic hashes, while the latter makes use of a neighbourhood watch and threshold-based analysis to detect and correct SF attacks. The scheme proposed here is capable of detecting a selective forwarding attack with over 96% accuracy and successfully identifying the malicious node with 83% accuracy.

3.
Nat Prod Commun ; 10(8): 1395-8, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26434126

RESUMO

Glibenclamide and thymoquinone plasma concentrations were analysed using a sensitive RP-HPLC method, and non-compartmental model pharmacokinetic parameters were calculated. The maximum reduction in blood glucose level was observed 3 hours following glibenclamide administration, which reached 47.4% of baseline, whereas it was reduced by 53.0% to 56.2% when co-administrated with thymoquinone. Plasma concentration of glibenclamide was increased by 13.4% and 21.8% by the co-administration of thymoquinone as single and multiple doses, respectively (P<0.05). The AUC and TI/2 of glibenclamide were also increased respectively by 32.0% and 17.4% with a thymoquinone single dose, and by 52.5% and 92.8% after chronic treatment. Furthermore, diabetic rats treated with thymoquinone demonstrated a marked decrease in hepatic protein expressions of CYP3A2 and CYP2C 11 enzymes that are responsible for the metabolism of glibenclamide. The current data suggest that thymoquinone exhibits a synergistic effect with glibenclamide on glucose level, which could be explained by reducing CYP450 activity at the protein level.


Assuntos
Benzoquinonas/administração & dosagem , Diabetes Mellitus Experimental/tratamento farmacológico , Glibureto/farmacocinética , Hipoglicemiantes/farmacocinética , Nigella/química , Extratos Vegetais/administração & dosagem , Animais , Hidrocarboneto de Aril Hidroxilases/genética , Hidrocarboneto de Aril Hidroxilases/metabolismo , Glicemia/metabolismo , Citocromo P-450 CYP3A/genética , Citocromo P-450 CYP3A/metabolismo , Família 2 do Citocromo P450 , Diabetes Mellitus Experimental/enzimologia , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/metabolismo , Modelos Animais de Doenças , Interações Medicamentosas , Humanos , Masculino , Ratos , Ratos Wistar , Esteroide 16-alfa-Hidroxilase/genética , Esteroide 16-alfa-Hidroxilase/metabolismo
4.
Biopharm Drug Dispos ; 28(3): 105-11, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17230598

RESUMO

Abouthiouzine is a novel antithyroid agent with a profile of fewer reported adverse effects than other currently used drugs. The purpose of this current work was to explore, for the first time, the disposition of abouthiouzine following intravenous and oral administration using an animal model; also, to study its plasma protein binding properties. Abouthiouzine (2 mg/kg intravenously) was administered to healthy male Vole rabbits and Beagle dogs. A dose of 20 mg/kg of the drug was also given orally to another group of Beagle dogs. Abouthiouzine plasma concentrations were measured using an HPLC method, and its pharmacokinetic parameters were determined by non-compartmental analysis. Abouthiouzine plasma protein binding was determined using an ultrafiltration technique. The drug was quickly eliminated from the rabbit and dog systemic circulations with terminal half-lives (T(1/2 lambda)) of 0.7 h and 1.9 h, respectively. The calculated T(1/2 lambda) following the oral administration in dogs was 1.8 h. Total abouthiouzine clearance (CL) in rabbits was 7.84+/-0.87 ml/min/kg, and 4.03+/-0.83 ml/min/kg in dogs. The apparent volume of distribution at steady state (V(ss)) in rabbits and dogs was 360.09+/-63.41 ml/kg and 481.10+/-62.64 ml/kg, respectively. The absolute oral bioavailability in dogs was approximately 16%, which may indicate poor absorption characteristics of the pure drug and/or an extensive first past effect. Protein binding studies have demonstrated that abouthiouzine has moderate-to-high binding properties ( approximately 63%-86%). Further studies are needed to evaluate the route of elimination of abouthiouzine in these animal models including any metabolite formation and the role of enterohepatic recycling in this process.


Assuntos
Antitireóideos/farmacocinética , Poliaminas/farmacocinética , Piridinas/farmacocinética , Administração Oral , Animais , Antitireóideos/administração & dosagem , Área Sob a Curva , Disponibilidade Biológica , Proteínas Sanguíneas/metabolismo , Cromatografia Líquida de Alta Pressão , Cães , Avaliação Pré-Clínica de Medicamentos , Injeções Intravenosas , Masculino , Modelos Animais , Poliaminas/administração & dosagem , Ligação Proteica , Piridinas/administração & dosagem , Coelhos , Especificidade da Espécie , Distribuição Tecidual , Ultrafiltração
5.
Vet Anaesth Analg ; 33(4): 241-5, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16764589

RESUMO

OBJECTIVES: The aim of this work was to examine the pharmacokinetics of diclofenac (DCLF) in sheep after intravenous (IV) and intramuscular (IM) dosing. ANIMALS: Healthy male Najdi sheep. MATERIALS AND METHODS: Diclofenac (1 mg kg(-1)) was administered to ten clinically healthy-male Najdi sheep IV or IM (n = 5 each). Blood samples (5 mL) were collected and serum was separated for drug analysis by high-performance liquid chromatography with UV detection. Diclofenac pharmacokinetic parameters were determined by noncompartmental analysis. RESULTS: Diclofenac is quickly eliminated from sheep with a terminal T(1/2lambda) of 2-3 hours for both routes of administration. Total DCLF clearance after IV and IM administration was 87.86 +/- 24.10 and 85.69 +/- 40.76 mL kg(-1) hour(-1) respectively. The absolute bioavailability of IM DCLF appears to be approximately 100%. CONCLUSIONS AND CLINICAL RELEVANCE: The drug should be administered two to three times daily in sheep by IM or IV injection to maintain therapeutic concentrations. Additional studies are needed to evaluate the route of elimination of DCLF in sheep including metabolites formation and the significance of enterohepatic circulation.


Assuntos
Anti-Inflamatórios não Esteroides/farmacocinética , Diclofenaco/farmacocinética , Ovinos/metabolismo , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/sangue , Área Sob a Curva , Diclofenaco/administração & dosagem , Diclofenaco/sangue , Injeções Intramusculares/veterinária , Injeções Intravenosas/veterinária , Masculino
6.
Artigo em Inglês | MEDLINE | ID: mdl-15686983

RESUMO

Abouthiouzine is a newly synthesized antithyroid agent with a proposed less adverse effects profile than other currently used drugs. A simple and rapid reversed phase high performance liquid chromatography assay was developed to determine the concentration of abouthiouzine in human plasma. The procedure involved extraction of the drug and propranolol (internal standard) from the plasma using ethylacetate. The extract was evaporated under nitrogen and the residue was constituted with the mobile phase and injected onto micro-Bondapack phenyl column (10 microm, 3.9 mm x 150 mm). The mobile phase consisted of 10 mM potassium dihydrogen phosphate buffer, acetonitrile, and methanol in the ratio of 60:25:15 (v/v/v, pH=3.0), which was delivered at a rate of 1.5 ml/min. Abouthiouzine and the internal standard were monitored using UV detection at 240 nm; the run time was less than 5 min. The detection limit of abouthiouzine is 0.5 microg/ml. The within- and between-day coefficients of variation were less than 7%. Our method has been successfully used to measure abouthiouzine plasma concentrations in a rabbit model following an intravenous administration of the drug.


Assuntos
Antitireóideos/sangue , Poliaminas/sangue , Piridinas/sangue , Antitireóideos/farmacocinética , Calibragem , Humanos , Poliaminas/farmacocinética , Piridinas/farmacocinética , Padrões de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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