Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
1.
Sensors (Basel) ; 23(11)2023 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-37299864

RESUMEN

The fish industry experiences substantial illegal, unreported, and unregulated (IUU) activities within traditional supply chain systems. Blockchain technology and the Internet of Things (IoT) are expected to transform the fish supply chain (SC) by incorporating distributed ledger technology (DLT) to build trustworthy, transparent, decentralized traceability systems that promote secure data sharing and employ IUU prevention and detection methods. We have reviewed current research efforts directed toward incorporating Blockchain in fish SC systems. We have discussed traceability in both traditional and smart SC systems that make use of Blockchain and IoT technologies. We demonstrated the key design considerations in terms of traceability in addition to a quality model to consider when designing smart Blockchain-based SC systems. In addition, we proposed an Intelligent Blockchain IoT-enabled fish SC framework that uses DLT for the trackability and traceability of fish products throughout harvesting, processing, packaging, shipping, and distribution to final delivery. More precisely, the proposed framework should be able to provide valuable and timely information that can be used to track and trace the fish product and verify its authenticity throughout the chain. Unlike other work, we have investigated the benefits of integrating machine learning (ML) into Blockchain IoT-enabled SC systems, focusing the discussion on the role of ML in fish quality, freshness assessment and fraud detection.


Asunto(s)
Cadena de Bloques , Productos Pesqueros , Internet de las Cosas , Animales , Industria de Alimentos
2.
Sensors (Basel) ; 23(11)2023 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-37299875

RESUMEN

This study is directed towards developing a fast, non-destructive, and easy-to-use handheld multimode spectroscopic system for fish quality assessment. We apply data fusion of visible near infra-red (VIS-NIR) and short wave infra-red (SWIR) reflectance and fluorescence (FL) spectroscopy data features to classify fish from fresh to spoiled condition. Farmed Atlantic and wild coho and chinook salmon and sablefish fillets were measured. Three hundred measurement points on each of four fillets were taken every two days over 14 days for a total of 8400 measurements for each spectral mode. Multiple machine learning techniques including principal component analysis, self-organized maps, linear and quadratic discriminant analyses, k-nearest neighbors, random forest, support vector machine, and linear regression, as well as ensemble and majority voting methods, were used to explore spectroscopy data measured on fillets and to train classification models to predict freshness. Our results show that multi-mode spectroscopy achieves 95% accuracy, improving the accuracies of the FL, VIS-NIR and SWIR single-mode spectroscopies by 26, 10 and 9%, respectively. We conclude that multi-mode spectroscopy and data fusion analysis has the potential to accurately assess freshness and predict shelf life for fish fillets and recommend this study be expanded to a larger number of species in the future.


Asunto(s)
Inteligencia Artificial , Peces , Animales , Espectrometría de Fluorescencia/métodos
3.
Biochem Biophys Res Commun ; 413(2): 164-70, 2011 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-21871870

RESUMEN

Up to now, all reported Ca(2+)-regulated photoproteins, except for mnemiopsin, have been cloned and expressed in Escherichia coli. In this study, the cDNA for an isotype of mnemiopsin, from the ctenophore Mnemiopsis leidyi, has been cloned, sequenced, and functionally expressed. The full length cDNA encoding mnemiopsin of M. leidyi was 624 bp open reading frame encoding a protein of 207 amino acid residues with calculated molecular mass of ∼24 kDa. The deduced amino acid sequence showed 90% and 84% identity to berovine (from ctenophore Beroe abyssicola) and bolinopsin 2 (from the ctenophore Bolinopsis infundibulum) respectively. In contrast to all known EF-hand in photoproteins, a unique EF-hand motif was found in mnemiopsin, in which a conserved glycine is substituted with glutamic acid. According to the results, the optimum pH was 9.0, time course of regeneration was 15 h and its Ca(2+) sensitivity was lower than aequorin. Results of pK(a) calculation for ionizable residues, motif scan and hydrophobic interactions of cavity aromatic residues of mnemiopsin in comparison with aequorin showed different patterns in these two photoproteins. In addition, experimental results are confirmed with the theoretical studies.


Asunto(s)
Calcio/metabolismo , Ctenóforos/metabolismo , Proteínas Luminiscentes/metabolismo , Aequorina/química , Secuencia de Aminoácidos , Animales , Calcio/farmacología , Ctenóforos/efectos de los fármacos , Ctenóforos/genética , Concentración de Iones de Hidrógeno , Imidazoles/química , Proteínas Luminiscentes/química , Proteínas Luminiscentes/genética , Datos de Secuencia Molecular , Conformación Proteica , Pirazinas/química
4.
Acta Medica (Hradec Kralove) ; 53(3): 147-51, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21171527

RESUMEN

Muslims abstain from eating, drinking and smoking from dawn to sunset during the holy month of Ramadan. Prolonged fasting is thought to be among risk factors for many diseases, e.g., cardiovascular, gastrointestinal and various infectious diseases. It could also play a part in several eye diseases, including dry eye syndrome, glaucoma, and cataract. Toxic and oxidative effects due to increased concentrations of some biochemicals as a result of reduction in tear volume thought to play an important role in damaging ocular tissue. Human tear is an important biological fluid similar to blood in many aspects. Tear film is composed of three basic layers i.e. lipid, aqueous and mucin. The tear film covering the ocular surface presents a mechanical and antimicrobial barrier, and endures an optical refractive surface. The aim of this study was to analyze and compare tear protein of volunteers during fasting. Using two reliable analytical methods, i.e. electrophoresis and high performance liquid chromatography (HPLC), we compared tear protein content of sixty volunteers (35 males and 25 females, 23-27 years old) during fasting in holly month of Ramadan (FAST: n = 62) and one month before Ramadan (CTRL: n = 60). The results showed that some identified tear proteins decreased during fasting. On the other hand, the activity of some enzymes such as lysozyme, lactoferrin and alpha amylase also decreased in fasting samples. Electrophoresis results showed that tear protein patterns in FAST (P < 0.05) were different from those of CTRL. There were a few more protein peaks in the FAST group (P < 0.005) than in CTRL.


Asunto(s)
Proteínas del Ojo/análisis , Ayuno , Adulto , Cromatografía Líquida de Alta Presión , Electroforesis en Gel de Poliacrilamida , Ayuno/efectos adversos , Femenino , Humanos , Islamismo , Masculino
5.
FEMS Immunol Med Microbiol ; 50(3): 319-23, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17521395

RESUMEN

The herpes simplex viruses are important causes of disease worldwide. Herpes simplex virus type 1 (HSV-1) is the primary cause of oral-facial and pharyngeal infections and may cause herpetic whitlow, eye infections as well as severe and sometimes dangerous infections of the eyes and brain. HSV-1 also accounts for 10-15% of all genital herpetic infections. Therefore, laboratory diagnosis of this virus and development of diagnostic serological techniques for HSV-1 is of particular importance. In the present study, pTrc His2A-gG1 plasmid, containing the full-length glycoprotein G (gG) protein, was produced in a prokaryotic system for the first time. Upon confirmation of a 37-kDa gG-1 protein production in a prokaryotic system based on western blotting and monoclonal antibodies, the protein was produced at a large scale and purified by ion-exchange chromatography using DEAE-sepharose. An HSV-1 type-specific diagnostic kit was designed and developed and the specificity and sensitivity of this kit were demonstrated to be 89.5% and 100%, respectively, as compared with a commercially available kit. A significant correlation was shown between the developed kit and the commercial kit.


Asunto(s)
Ensayo de Inmunoadsorción Enzimática/métodos , Herpes Simple/diagnóstico , Herpesvirus Humano 1/aislamiento & purificación , Juego de Reactivos para Diagnóstico , Proteínas Recombinantes/biosíntesis , Proteínas del Envoltorio Viral/biosíntesis , Escherichia coli/genética , Vectores Genéticos , Humanos , Plásmidos/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/aislamiento & purificación , Proteínas del Envoltorio Viral/aislamiento & purificación
6.
J Biochem Mol Biol ; 40(3): 315-24, 2007 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-17562282

RESUMEN

The novel alpha-amylase purified from locally isolated strain, Bacillus sp. KR-8104, (KRA) (Enzyme Microb Technol; 2005; 36: 666-671) is active in a wide range of pH. The enzyme maximum activity is at pH 4.0 and it retains 90% of activity at pH 3.5. The irreversible thermoinactivation patterns of KRA and the enzyme activity are not changed in the presence and absence of Ca(2+) and EDTA. Therefore, KRA acts as a Ca(2+)-independent enzyme. Based on circular dichroism (CD) data from thermal unfolding of the enzyme recorded at 222 nm, addition of Ca(2+) and EDTA similar to its irreversible thermoinactivation, does not influence the thermal denaturation of the enzyme and its T(m). The amino acid sequence of KRA was obtained from the nucleotide sequencing of PCR products of encoding gene. The deduced amino acid sequence of the enzyme revealed a very high sequence homology to Bacillus amyloliquefaciens (BAA) (85% identity, 90% similarity) and Bacillus licheniformis alpha-amylases (BLA) (81% identity, 88% similarity). To elucidate and understand these characteristics of the alpha-amylase, a model of 3D structure of KRA was constructed using the crystal structure of the mutant of BLA as the platform and refined with a molecular dynamics (MD) simulation program. Interestingly enough, there is only one amino acid substitution for KRA in comparison with BLA and BAA in the region involved in the calcium-binding sites. On the other hand, there are many amino acid differences between BLA and KRA at the interface of A and B domains and around the metal triad and active site area. These alterations could have a role in stabilizing the native structure of the loop in the active site cleft and maintenance and stabilization of the putative metal triad-binding site. The amino acid differences at the active site cleft and around the catalytic residues might affect their pKa values and consequently shift its pH profile. In addition, the intrinsic fluorescence intensity of the enzyme at 350 nm does not show considerable change at pH 3.5-7.0.


Asunto(s)
Calcio/metabolismo , alfa-Amilasas/química , alfa-Amilasas/metabolismo , Secuencia de Aminoácidos , Bacillus/enzimología , Bacillus/genética , Dicroismo Circular , Simulación por Computador , Concentración de Iones de Hidrógeno , Modelos Moleculares , Datos de Secuencia Molecular , Estructura Secundaria de Proteína , Estructura Terciaria de Proteína , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido , Homología Estructural de Proteína , Temperatura , alfa-Amilasas/genética
7.
Tuberc Respir Dis (Seoul) ; 78(3): 253-7, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26175780

RESUMEN

BACKGROUND: Tuberculosis (TB) is the leading cause of mortality among human immunodeficiency virus (HIV) patients and the majority of them occur in developing countries. The aims of the present study were to determine the frequency of HIV/TB co-infection and other probable associated factors. METHODS: This 10 year retrospective study was conducted on 824 HIV patients in the south-west of Iran. HIV infection was diagnosed by the enzyme linked immunosorbent assay and confirmed by Western blot. TB diagnosis was based on consistency of the clinical manifestations, chest X-ray, and microscopic examination. Drug susceptibility testing was done by the proportional method on Löwenstein-Jensen media. RESULTS: Of 824 HIV patients, 59 (7.2%) were identified as TB co-infected and the majority (86.4%) of them were male. Of the overall TB infected patients, 6 cases (10.2%) showed multidrug-resistant with the mean CD4+ lymphocyte count of 163±166 cells/mm(3). The main clinical forms of TB were pulmonary (73%). There was a significant (p<0.05) correlation between TB infection and CD4+ lymphocyte counts ≤200 cells/mm(3), gender, prison history, addiction history, and highly active anti-retroviral therapy. CONCLUSION: We reported novel information on frequency of HIV/TB co-infection and multidrug resistant-TB outcome among co-infected patients that could facilitate better management of such infections on a global scale.

8.
Appl Biochem Biotechnol ; 119(1): 41-50, 2004 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15496727

RESUMEN

A new alpha-amylase was extracted from a recently found strain of Bacillus sp. and purified by ion-exchange chromatography. Sodium dodecyl sulfate polyacrylamide gel electrophoresis showed a single band for the purified enzyme with an apparent molecular weight of 59 kDa. The optimum temperature and pH range of the enzyme were 40-60 degrees C and 4.5-7.5, respectively, and its activation energy was 1.974 kcal/mol. The Km value for the enzyme activity on soluble starch was 4 mg/mL, and the Tm values obtained from the circular dichroism (CD) results of thermal unfolding were 78.7 and 80.2 degrees C in the absence and presence of the calcium, respectively. The enzyme was almost completely inhibited by the addition of Fe3+, Mn2+, and Zn2+ and was activated by EDTA, Cr3+, and Al3+. Moreover, it was partially inhibited by Ca2+, Ba2+, Ni2+, and Co2+. Proteolytic digestion of the enzyme using trypsin combined with results from Tm using CD and irreversible thermoinactivation suggests that this enzyme can be considered a moderate thermophile with both mild flexibility and rigidity.


Asunto(s)
Bacillus/enzimología , Proteínas Bacterianas , Calcio/metabolismo , alfa-Amilasas , Proteínas Bacterianas/química , Proteínas Bacterianas/aislamiento & purificación , Proteínas Bacterianas/metabolismo , Dicroismo Circular , Estabilidad de Enzimas , Concentración de Iones de Hidrógeno , Metales/metabolismo , Temperatura , alfa-Amilasas/química , alfa-Amilasas/aislamiento & purificación , alfa-Amilasas/metabolismo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA