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1.
Fish Physiol Biochem ; 49(6): 1409-1419, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37943346

RESUMEN

Approximately 80% of luminous organisms live in the oceans, and considerable diversity of life dependence on bioluminescence has been observed in marine organisms. Among vertebrates, luminous fish species are the only group of vertebrates that have the ability to emit bioluminescent light. Meanwhile, the lantern fish family (Myctophidae), with 33 genera all of which have the ability to emit light, is considered the most prominent family among the luminous fish of the deep oceans and seas. Lantern fish Benthosema pterotum has bioluminescence properties due to the presence of photophores scattered in its ventral-lateral region. However, no research has been performed on its bioluminescence system and light emission mechanism. The present research aimed to assess the type of bioluminescence, pigment, photoprotein, or luciferin-luciferase system in B. pterotum. In order to determine the type of light-emitting system in B. pterotum species, several specific experiments were designed and performed. It was shown that the light emission system in B. pterotum species is categorized into the luciferin-luciferase type. Conducting this research was not only innovative, but it also could be the beginning of further research in the field of marine biochemistry and production of the recombinant active forms of enzymes for industrial, commercial, medical, and pharmaceutical purposes.


Asunto(s)
Peces , Luciferinas , Animales , Luciferasas/genética , Mediciones Luminiscentes
3.
Adv Healthc Mater ; 11(20): e2201583, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35916145

RESUMEN

Conventional drug delivery systems are challenged by concerns related to systemic toxicity, repetitive doses, drug concentrations fluctuation, and adverse effects. Various drug delivery systems are developed to overcome these limitations. Nanomaterials are employed in a variety of biomedical applications such as therapeutics delivery, cancer therapy, and tissue engineering. Physiochemical nanoparticle assembly techniques involve the application of solvents and potentially harmful chemicals, commonly at high temperatures. Genetically engineered organisms have the potential to be used as promising candidates for greener, efficient, and more adaptable platforms for the synthesis and assembly of nanomaterials. Genetically engineered carriers are precisely designed and constructed in shape and size, enabling precise control over drug attachment sites. The high accuracy of these novel advanced materials, biocompatibility, and stimuli-responsiveness, elucidate their emerging application in controlled drug delivery. The current article represents the research progress in developing various genetically engineered carriers. Organic-based nanoparticles including cellulose, collagen, silk-like polymers, elastin-like protein, silk-elastin-like protein, and inorganic-based nanoparticles are discussed in detail. Afterward, viral-based carriers are classified, and their potential for targeted therapeutics delivery is highlighted. Finally, the challenges and prospects of these delivery systems are concluded.


Asunto(s)
Portadores de Fármacos , Sistema de Administración de Fármacos con Nanopartículas , Celulosa , Portadores de Fármacos/química , Elastina , Sistema de Administración de Fármacos con Nanopartículas/química , Polímeros , Seda
4.
Mar Biotechnol (NY) ; 24(3): 599-613, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35507234

RESUMEN

The present study focused on the cloning, expression, and characterization of L-asparaginase of marine Pseudomonas aeruginosa HR03 isolated from fish intestine. Thus, a gene fragment containing the L-asparaginase sequence of Pseudomonas aeruginosa HR03 isolated from the fish intestine was cloned in the pET21a vector and then expressed in Escherichia coli BL21 (DE3) cells. Thereafter, the recombinant L-asparaginase (HR03Asnase) was purified by nickel affinity chromatography, and the enzymatic properties of HR03Asnase, including the effects of pH and temperature on HR03Asnase activity and its kinetic parameters, were determined. The recombinant enzyme HR03Asnase showed the highest similarity to type I L-asparaginase from Pseudomonas aeruginosa. The three-dimensional (3D) modeling results indicate that HR03Asnase exists as a homotetramer. Its molecular weight was 35 kDa, and the maximum activity of the purified enzyme was observed at pH8 and at 40 °C. The km and Vmax of the enzyme obtained with L-asparagine as substrate were 10.904 mM and 3.44 × 10-2 mM/min, respectively. The maximum activity of HR03Asnase was reduced by 50% at 90 °C after 10-min incubation; however, the enzyme maintained more than 20% of its activity after 30-min incubation. This enzyme also maintained almost 50% of its activity at pH 12 after 40-min incubation. The evaluation of pH and temperature stability of HR03Asnase showed that the enzyme has a wide range of activity, which is a suitable characteristic for its application in different industries. Overall, the results of the present study indicate that marine sources are promising biological reservoirs for enzymes to be used for biotechnological purposes, and marine thermostable HR03Asnase is likely a potential candidate for its future usage in the pharmaceutical and food industries.


Asunto(s)
Asparaginasa , Pseudomonas aeruginosa , Animales , Asparaginasa/química , Asparaginasa/genética , Asparaginasa/metabolismo , Asparagina/metabolismo , Estabilidad de Enzimas , Escherichia coli/genética , Escherichia coli/metabolismo , Concentración de Iones de Hidrógeno , Cinética , Pseudomonas aeruginosa/genética , Proteínas Recombinantes/metabolismo
5.
Environ Sci Pollut Res Int ; 29(16): 23712-23720, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34813012

RESUMEN

Despite the increasing interest in mangroves as one of the most carbon-rich ecosystems, arid mangroves are still poorly investigated. We aimed to improve the knowledge of biomass and soil carbon sequestration for an arid mangrove forest located at the Azini creek, Sirik, Hormozgan Province (Iran). We investigated the biomass and organic carbon stored in the above and belowground biomass for three different regions selected based on the composition of the principal species: (1) Avicennia marina, (2) mixed forest of A. marina and Rhizophora mucronata, and (3) R. mucronata. Topsoil organic carbon storage to 30 cm depth was also estimated for each analyzed area. Biomass carbon storage, considering both aboveground (AGB) and belowground biomass (BGB), was significantly different between the cover areas. Overall, the mean forest biomass (MFB) was 283.1 ± 89 Mg C ha-1 with a mean C stored in the biomass of 128.9 ± 59 Mg C ha-1. Although pure Rhizophora stand showed the lowest value of above and below tree carbon (AGC + BGC); 17.6 ± 1.9 Mg C ha-1), soil organic carbon stock in sites under Rhizophora spp. was significantly higher than in the site with pure stand of Avicennia spp. Overall, forest soil stored the highest proportion of Sirik mangrove ecosystem organic carbon (59%), with a mean value of 188.3 ± 27 Mg C ha-1. These results will contribute to broaden the knowledge and the dataset available, reducing the uncertainties related to estimates and modeling of carbon pools in arid mangrove ecosystem, which also represent an important climatic threshold of mangrove worldwide distribution.


Asunto(s)
Carbono , Suelo , Biomasa , Carbono/análisis , Secuestro de Carbono , Ecosistema , Bosques , Irán , Humedales
6.
PLoS One ; 16(7): e0252384, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34214101

RESUMEN

Early prediction of patient mortality risks during a pandemic can decrease mortality by assuring efficient resource allocation and treatment planning. This study aimed to develop and compare prognosis prediction machine learning models based on invasive laboratory and noninvasive clinical and demographic data from patients' day of admission. Three Support Vector Machine (SVM) models were developed and compared using invasive, non-invasive, and both groups. The results suggested that non-invasive features could provide mortality predictions that are similar to the invasive and roughly on par with the joint model. Feature inspection results from SVM-RFE and sparsity analysis displayed that, compared with the invasive model, the non-invasive model can provide better performances with a fewer number of features, pointing to the presence of high predictive information contents in several non-invasive features, including SPO2, age, and cardiovascular disorders. Furthermore, while the invasive model was able to provide better mortality predictions for the imminent future, non-invasive features displayed better performance for more distant expiration intervals. Early mortality prediction using non-invasive models can give us insights as to where and with whom to intervene. Combined with novel technologies, such as wireless wearable devices, these models can create powerful frameworks for various medical assignments and patient triage.


Asunto(s)
COVID-19/mortalidad , Pandemias , SARS-CoV-2 , Máquina de Vectores de Soporte , Adulto , Anciano , Anciano de 80 o más Años , Comorbilidad , Registros Electrónicos de Salud , Femenino , Predicción , Humanos , Masculino , Persona de Mediana Edad , Modelos Teóricos , Riesgo , Índice de Severidad de la Enfermedad , Evaluación de Síntomas , Triaje , Adulto Joven
7.
J Therm Biol ; 92: 102692, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32888577

RESUMEN

Mangroves are ideal habitat for a variety of marine species especially brachyuran crabs as the dominant macrofauna. However, the global distribution, endemicity, and latitudinal gradients of species richness in mangrove crabs remains poorly understood. Here, we assessed whether species richness of mangrove crabs decreases towards the higher latitudes and tested the importance of environmental factors such as Sea Surface Temperature (SST) in creating the latitudinal gradients in species richness of mangrove crabs. A total of 8262 distribution records of 481 species belonging to six families of mangrove crabs including Camptandriidae, Dotillidae, Macrophthalmidae, Ocypodidae, Sesarmidae, and Oziidae were extracted from open-access databases or collected by the authors, quality controlled, cleaned, and analyzed. Species richness was plotted against 5° latitudinal bands in relation to environmental factors. The R software and ArcGIS 10.6.1 were used to analyze the species latitudinal range and richness as well as to map the distribution of mangrove forest, endemic species, species geographical distribution records, and biogeographic regions. The Indo-West Pacific showed the highest species richness of mangrove crabs where more than 65% of species were found in the Indian Ocean and along the western Pacific Ocean. Our results showed that there are 11 significantly different biogeographic regions of mangrove crabs. The highest endemicity rate was observed in the NW Pacific Ocean (29%). Latitudinal patterns of species richness in Macrophthalmidae, Ocypodidae, and Sesarmidae showed an increasing trend from the poles toward the intermediate latitudes including one dip near the equator. However, latitudinal gradients in Camptandriidae, Dotillidae, and Oziidae were unimodal increasing from the higher latitudes towards the equator. Species richness per 5° latitudinal bands significantly increased following mean SST mean (°C), calcite, euphotic depth (m), and mangrove area (km2) across all latitudes, and tide average within each hemisphere. Species richness significantly decreased with dissolved O2 (ml l-1) and nitrate (µmol l-1) over all latitudes and in the southern hemisphere. The climax of global latitudinal species richness for some mangrove was observed along latitudes 20° N and 15°-25° S, not at the equator. This can suggest that temperature is probably the key driver of latitudinal gradients of mangrove crabs' species richness. Species richness and mangrove area were also highly correlated.


Asunto(s)
Biodiversidad , Braquiuros/fisiología , Animales , Ecosistema , Océano Pacífico , Temperatura
8.
Sci Adv ; 6(17): eaba3252, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32426469

RESUMEN

A smart contact lens can be used as an excellent interface between the human body and an electronic device for wearable healthcare applications. Despite wide investigations of smart contact lenses for diagnostic applications, there has been no report on electrically controlled drug delivery in combination with real-time biometric analysis. Here, we developed smart contact lenses for both continuous glucose monitoring and treatment of diabetic retinopathy. The smart contact lens device, built on a biocompatible polymer, contains ultrathin, flexible electrical circuits and a microcontroller chip for real-time electrochemical biosensing, on-demand controlled drug delivery, wireless power management, and data communication. In diabetic rabbit models, we could measure tear glucose levels to be validated by the conventional invasive blood glucose tests and trigger drugs to be released from reservoirs for treating diabetic retinopathy. Together, we successfully demonstrated the feasibility of smart contact lenses for noninvasive and continuous diabetic diagnosis and diabetic retinopathy therapy.

9.
Andrologia ; 52(6): e13604, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32324915

RESUMEN

Cryopreservation is the most effective method for preserving semen for a long period of time. However, during the freeze-thaw process, production of reactive oxygen species (ROS) leads to a steep reduction in sperm fertility indices. In this study, we tested the effects of the extract of the coelomic cavity of five Holotheria parva, a marine organism rich in antioxidants, for its ROS-scavenging activity and cryoprotective effects on oxidative stress. Using a total of 50 semen samples, our results demonstrated that doses of 250 and 500 µg/ml of H. parva coelomic cavity extract significantly increased sperm vitality as compared to the control (p < .05). The addition of 250 µg/ml of the extract exerted a significant positive effect on sperm motility. Moreover, sperm DNA damage and ROS production were significantly reduced at extract concentrations of 250 and 500 µg/ml (p < .05). To the best of our knowledge, the results of this study represent the first demonstration of the possibility of improving sperm parameters and reducing ROS production and DNA damage by supplementing sperm freezing media with H. parva coelomic extract. Our results suggested that H. parva coelomic extract could be useful for improving the fertilising ability of frozen-thawed human semen.


Asunto(s)
Criopreservación , Daño del ADN/efectos de los fármacos , Depuradores de Radicales Libres/farmacología , Holothuria , Estrés Oxidativo/efectos de los fármacos , Preservación de Semen , Espermatozoides/efectos de los fármacos , Extractos de Tejidos/farmacología , Animales , Supervivencia Celular , Cromatina/efectos de los fármacos , Humanos , Masculino , Proyectos Piloto , Especies Reactivas de Oxígeno/metabolismo , Análisis de Semen , Motilidad Espermática/efectos de los fármacos
10.
Int J Biol Macromol ; 142: 811-821, 2020 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-31622713

RESUMEN

The monooxygenase enzymes, cytochrome P450s (CYPs), are ubiquitous in their presence and versatile in their functions. They are indispensable for hormone synthesis, dietary metabolism, and detoxification among other roles. CYPs from marine organisms are interesting candidates for recruitment in drug biotransformation, synthesis of therapeutics, bioconversion of xenobiotics, degradation of chemical carcinogens, and for use as ecotoxicological tools. However, excess CYP production in marine organisms indicates a 'stressed condition', which has a negative impact on the ecological balance. This review discusses the CYPs in marine organisms of various phyla, their application potentials, as well as the need to restore normal CYP level in them to regulate the relationship between marine organisms and environment.


Asunto(s)
Organismos Acuáticos/química , Sistema Enzimático del Citocromo P-450/química , Sistema Enzimático del Citocromo P-450/metabolismo , Animales , Biocatálisis , Biotecnología , Biotransformación , Sistema Enzimático del Citocromo P-450/genética , Regulación de la Expresión Génica , Humanos , Contaminantes Químicos del Agua/metabolismo , Xenobióticos/química
11.
Mater Sci Eng C Mater Biol Appl ; 102: 324-340, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31147005

RESUMEN

Despite the fact that magnetic iron oxide nanoparticles (Fe3O4-MNPs) considered as the most promising nanoparticles (NPs) in biomedicine and environmental biotechnology, their safety and ecotoxicological impacts of biogenic and chemogenic routes of Fe3O4-MNPs in the marine aquatic system is scarcely studied. In this work, we report the optimized and suitable phyco-synthesis route for nano-Fe3O4 based on the six selected species of the Persian Gulf seaweeds: Ulva prolifera, U. flexuosa, U. linza, U. intestinalis, U. clathrata, and Sargassum boveanum. Moreover, antibacterial activities and acute zooplanktonic responses in Artemia salina and acorn barnacle Amphibalanus amphitrite to chemogenic and biogenic Fe3O4-MNPs, were evaluated. Although all the seaweeds extract showed reducing potential for Fe3O4-MNPs green synthesis - mainly on the basis of characterization results- the algal route selectivity has been demonstrated to be important for the biosynthesis of magnetite NPs. Herein, the cubo-spherical and polydisperse U. prolifera-derived Fe3O4-MNPs with particles sizes of 9.59 nm were the best ones. The comparative zooplanktonic cytotoxicity of chemo- and bio-route of Fe3O4-MNPs exhibited no acute toxicity in nauplii and adults of A. salina (96-h EC50 ≥ 1000 mg/L) and the potential of toxicity in A. amphitrite nauplii (48-h EC50 = 466.5 and 842.3 mg/L for chemo- and bio-route of Fe3O4-MNPs, respectively). The in vitro antimicrobial activity of both chemo- and bio-route of magnetite NPs to selective human pathogenic bacteria and fungi (i.e. n = 11) showed strong antagonistic activity against Staphylococcus epidermidis, Bacillus subtilis, B. pumulis, and Saccharomyces cerevisiae. In conclusion, these findings demonstrate the optimized phyco-fabrication of Fe3O4-MNPs as promising nontoxic approach in ecobiotechnology, the new insight about the potential adverse effects of chemosynthesized Fe3O4-MNPs to crustacean zoo-organisms after their possible entrance into the marine environments, and bio/chemo-route Fe3O4-MNPs as pivotal agent for nanoantimicrobials.


Asunto(s)
Antibacterianos/farmacología , Nanopartículas de Magnetita/química , Ulva/química , Zooplancton/efectos de los fármacos , Adsorción , Animales , Artemia/efectos de los fármacos , Bacterias/efectos de los fármacos , Bioensayo , Hongos/efectos de los fármacos , Nanopartículas de Magnetita/toxicidad , Nanopartículas de Magnetita/ultraestructura , Magnetometría , Pruebas de Sensibilidad Microbiana , Tamaño de la Partícula , Algas Marinas/química , Espectroscopía Infrarroja por Transformada de Fourier , Electricidad Estática , Termogravimetría , Thoracica/efectos de los fármacos , Pruebas de Toxicidad , Difracción de Rayos X
12.
Environ Pollut ; 237: 50-64, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29474987

RESUMEN

Following the recent progress in magnetic nanotechnology, concern over the optimal benefits and potential risks of iron oxide nanoparticles (Fe NPs), has increased. Hence, to minimize the negative impacts of inorganic Fe NPs, we report the phyco-synthesis and characterization of superparamagnetic Fe3O4 NPs via reduction of ferric/ferrous chloride solution (2:1 M ratio; 88 °C) with green macroalga, Ulva flexuosa (wulfen) J.Agardh aqueous extract. The biogenic process is clean, eco-friendly, rapid, and facile to handle. These green fabricated magnetite NPs are characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM), thermogravimetric analysis (TGA), particle size analysers (PSA), zeta potential (ZP) measurement, and vibrating sample magnetometry (VSM) techniques. The results confirmed that the cubo-spherical, polydisperse of biosynthesized Fe3O4 NPs with an average diameter of 12.3 nm was formed. The antagonistic effects of algal extract, chemo-route and U. flexuosa-derived Fe3O4 MgNPs on selective human pathogenic microbes (i.e. n = 11) resulted in strong antibacterial and moderate antifungal activity. The comparative toxic and reproductive effects of the chemo- and bio-routes of Fe3O4-MgNPs against rotifer B. rotundiformis exhibited low acute toxicity with a lower inducing effect of biogenic nano-magnetite on reduction rotifer reproductive rate than its chemogenic counterpart. In view of the nanoecotoxicity, though the current study covered a wide range of exposure concentrations (10-500 mg/L) of organic and inorganic nano sizes of Fe3O4 in brackish water rotifer, a biotoxicity assay at higher dosage or a comprehensive risk assessment in different aqua-organisms is recommended.


Asunto(s)
Antiinfecciosos/toxicidad , Compuestos Férricos/toxicidad , Nanopartículas/toxicidad , Pruebas de Toxicidad Aguda , Ulva/fisiología , Animales , Antibacterianos/farmacología , Óxido Ferrosoférrico/química , Humanos , Magnetismo , Microscopía Electrónica de Transmisión , Tamaño de la Partícula , Rotíferos , Espectroscopía Infrarroja por Transformada de Fourier , Ulva/efectos de los fármacos , Agua/química , Difracción de Rayos X
13.
Ecotoxicol Environ Saf ; 151: 236-241, 2018 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-29353173

RESUMEN

Superoxide dismutase (SOD) is the pivotal antioxidant enzyme that defends organisms against the oxidative stresses of superoxide radicals. In this experimental study, purification of SOD from the leaves of Avicennia marina (grey mangrove or white mangrove) from the family Acanthaceae, located in Sirik mangrove forest on the shore of the Gulf of Oman was performed, for the intended characterization of SOD. The Sirik AmSOD (A. marina SOD) expressed optimum activity in the pH range of 6-9 with the maximum activity at pH 8. The optimal temperature for Sirik AmSOD activity was 70°C. Comparison of the pH and temperature optima in two regions (the Persian Gulf and the Gulf of Oman) showed significant differences with P<0.05. The SOD from the Persian Gulf was more resistant against the environmental stressors, because of the biochemical adaption to this environment, which is harsher. The evidence from these results suggests that AmSOD has different characteristics in each place, and mangroves undergo different adaptations and require different protections. The results of the enzymatic research can be useful for ecological management of organisms.


Asunto(s)
Avicennia/enzimología , Monitoreo del Ambiente , Hojas de la Planta/enzimología , Superóxido Dismutasa-1/metabolismo , Contaminantes Químicos del Agua/análisis , Concentración de Iones de Hidrógeno , Océano Índico , Omán , Estrés Oxidativo , Estrés Fisiológico , Temperatura
14.
Chemosphere ; 191: 485-493, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29055873

RESUMEN

This study aimed to investigate the ecological risk assessment of Khamir, Tiyab, and Jagin estuaries and the impact of anthropogenic activities on these ecosystems during a one-year study period (April 2015 to March 2016) using trace metals as pollution indices. The sediment samples were collected from nine sampling stations, following a gradient of contamination from the industrial wastewater and shrimp farming effluents to the less impacted stations. Pollution indices (i.e. PERI and PLI) were applied to ascertain the sediment quality. Based on pollution indices, the overall pattern of environmental quality status demonstrated that industrial sewage and shrimp farming effluents are major sources of pollution in the Khamir and Tiyab estuaries, respectively. The sediments in the most stations in studied coastal ecosystems of Iran posed moderate or considerable ecological risk. Results from this study showed that Zn, Pb, Cu, and Cd were mostly derived from anthropogenic activities such as domestic sewage and industrial effluents. Also, the findings of this study revealed that the pollution indices are suitable for evaluating the environmental situation of coastal ecosystems and the separation of areas with less impacted by human activities from areas affected by these activities and could be used as a robust management tool for monitoring programs in coastal areas. Altogether, these findings could be useful in providing more effective and targeted strategies of development better management practices for coastal areas.


Asunto(s)
Monitoreo del Ambiente/métodos , Metales Pesados/análisis , Contaminantes Químicos del Agua/análisis , Agricultura , Ecología , Ecosistema , Estuarios , Sedimentos Geológicos , Océano Índico , Irán , Omán , Medición de Riesgo/métodos , Aguas del Alcantarillado , Oligoelementos/análisis
15.
Chronobiol Int ; 34(10): 1366-1376, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29064303

RESUMEN

A study was carried out to investigate the daily rhythms of locomotor and feeding activity of Khajoo, Schizothorax pelzami, a candidate species for freshwater aquaculture. Using self-feeder juvenile Khajoo were exposed to a 12/12 LD cycle to determine the rhythms of locomotor and feeding activity. The effects of feeding on locomotor and feeding activity of fish were also examined. Finally, the endogenous rhythmicity under different lighting condition tested. Fish displayed a strictly diurnal feeding and locomotor activities with 98% and 84% of the total activity occurred in the photophase, respectively. In scheduled feeding, both the L-group (fed in light) and the D-group (fed in the dark) showed a diurnal locomotor activity pattern. However, the L-group had a peak of locomotor activity near the feeding time, but the D-group had a scarce locomotor activity in the scatophase with no significant change at the mealtime. Most of the individuals display free-running rhythms when exposed to different lighting condition including, constant darkness, ultradian 45:45 min LD cycle and reversed DL photo cycle. Taken together the results of this study showed that both locomotor and feeding activity have diurnal rhythms in Khajoo S. pelzami, even fish feeding had taken place at night. Additionally, the free-running locomotor activity of the fish in the absence of external light stimuli, suggests the existence of an endogenous timing mechanism in this fish species.


Asunto(s)
Ritmo Circadiano , Cyprinidae/fisiología , Conducta Alimentaria , Locomoción , Animales , Acuicultura , Fotoperiodo
16.
Int J Biol Macromol ; 105(Pt 3): 1556-1562, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28720545

RESUMEN

A novel Cu/Zn-superoxide dismutase was extracted from Avicennia marina and purified. The sample was collected from Khamir port located in the north shore of Persian Gulf. The purification procedure comprised of (NH4)2SO4 precipitation followed by CM-Sephadex C-50 and DEAE-Sepharose chromatography, and gel filtration chromatography (Sephadex G-75). The enzyme with a characteristic molecular weight of 31kDa, measured by SDS-page, showed its highest catalytic efficiency at pH 8.0 and 50°C. Its activity was greatly inhibited by cyanide and hydrogen peroxide. The pH profile showed that the enzyme could maintain most of its activity at pH values ranging from 5 to 10. The temperature profile of this enzyme showed a broad range of activity compared with other superoxide dismutases. Catalytic hydrolysis rate followed Michaelis-Menten equation. The values of kcat and Km were obtained from Michaelis-Menten plot as 107000s-1 and 11.5µmol respectively. The evidences from kinetic and thermodynamic parameters suggest that Avicennia marina superoxide dismutase (AmSOD) can be used as a suitable enzyme for biotechnological and pharmacological applications.


Asunto(s)
Antioxidantes/metabolismo , Avicennia/enzimología , Superóxido Dismutasa/metabolismo , Antioxidantes/química , Estabilidad de Enzimas , Concentración de Iones de Hidrógeno , Industrias , Cinética , Peso Molecular , Superóxido Dismutasa/química , Temperatura
17.
Rev. biol. trop ; 65(1): 365-373, Jan.-Mar. 2017. tab, ilus
Artículo en Inglés | LILACS | ID: biblio-897548

RESUMEN

Abstract:Freshwater crab, Sodhiana iranica, is an endemic gecarcinucid crab that has been recently reported from Southern Iran. This research examined some reproductive aspects of S. iranica from Eelood freshwater spring, Southern Iran. Crabs were haphazardly sampled from April 2012 to April 2013, on a bimonthly basis. Measurements of Gonado-Somatic Index (GSI), Hepato-Somatic Index (HSI), oocyte diameter, and other aspects such as carapace width (CW) and total body weight (TW) were made in the captured specimens. Results showed a single seasonal reproductive cycle. Maturation and spawning occurred from December 2012 to April 2013 during the study period. The peaks of HSI were observed in April 2012 and February 2013. The oocyte diameter showed its most significant increase between August 2012 and February 2013. Considering the single seasonal breeding of S. iranica, a correct management, during the reproductive cycle, is necessary to support a healthy stock of this crab. Rev. Biol. Trop. 65 (1): 365-373. Epub 2017 March 01.


ResumenEl cangrejo agua dulce Sodhiana iranica es un cangrejo gecarcinucido que ha sido recientemente encontrado en el sur de Irán. Este trabajo examina algunos aspectos de la reproducción del cangrejo de agua dulce S. Iranica en el manantial Eelood del sur de Irán. Los cangrejos se muestrearon al azar entre abril 2012 y abril 2013 cada dos meses. Las mediciones del índice gonadosomático, el hepatosomático (HSI), el diámetro de los ovocitos y las observaciones de las etapas de maduración de los especímenes capturados, revelaron un único ciclo reproductivo estacional. La maduración y el desove se produjeron entre Diciembre 2012 y Abril 2013. El pico del índice hepatosomático se observó en Abril 2012 y Febrero 2013, respectivamente, y resultó más significativo el incremento en la media del diámetro de los ovocitos, que se produjo entre Agosto 2012 y Febrero 2013. En este estudio, se encontró que S. iranica se reproduce una vez al año estacionalmente. Por lo anterior, la gestión correcta durante el ciclo reproductivo de esta especie es necesaria para mantener la naturaleza y salud del stock de cangrejo.


Asunto(s)
Animales , Masculino , Femenino , Braquiuros/fisiología , Oocitos/fisiología , Reproducción/fisiología , Estaciones del Año , Maduración Sexual , Factores de Tiempo , Factores Sexuales , Agua Dulce , Irán
18.
Rev Biol Trop ; 65(1): 365-73, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29466651

RESUMEN

Freshwater crab, Sodhiana iranica, is an endemic gecarcinucid crab that has been recently reported from Southern Iran. This research examined some reproductive aspects of S. iranica from Eelood freshwater spring, Southern Iran. Crabs were haphazardly sampled from April 2012 to April 2013, on a bimonthly basis. Measurements of Gonado-Somatic Index (GSI), Hepato-Somatic Index (HSI), oocyte diameter, and other aspects such as carapace width (CW) and total body weight (TW) were made in the captured specimens. Results showed a single seasonal reproductive cycle. Maturation and spawning occurred from December 2012 to April 2013 during the study period. The peaks of HSI were observed in April 2012 and February 2013. The oocyte diameter showed its most significant increase between August 2012 and February 2013. Considering the single seasonal breeding of S. iranica, a correct management, during the reproductive cycle, is necessary to support a healthy stock of this crab.


Asunto(s)
Braquiuros/fisiología , Animales , Femenino , Agua Dulce , Irán , Masculino , Oocitos/fisiología , Reproducción/fisiología , Estaciones del Año , Factores Sexuales , Maduración Sexual , Factores de Tiempo
19.
Braz. arch. biol. technol ; 60: e17160532, 2017. tab, graf
Artículo en Inglés | LILACS | ID: biblio-951467

RESUMEN

ABSTRACT Increasingly burden of inhabitants growing in coastlines has led to damage in various mangrove expanses. Though these regions play as fish nursery grounds and are actual vital in stock assessments, there is no precise and state-of-the-art accessible information about them. Herein the catch records in the Qeshm island marine protected area (MPA) was studied by means of 11 stake-nets. Thoroughly, 81 specimens of 69 genera and 63 families were caught, which the main stream of them were discards. The salable fish were undeveloped which were frequently undersized in comparison with LM50. For Pampus argenteus as well, lone 15.3% of the caught those remained in the permissible catch size. Henceforward, this catch conformation would be there an impending hazard to fish stocks. The chief relative abundance and weight based specimens were Dussumieria acuta (10.05%) and Arius maculatus (5.9%), respectively. Encompassing seven species, the Clupeidae was the utmost rich family in the catch conformation. Ultimately, overall once yearly catch by aforementioned stake-nets surrounded by the mangrove woodlands in the Qeshm Island marine protected area was appraised to be 186.77-188.75 tonnes, approximately.

20.
Lab Chip ; 15(18): 3638-60, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26245815

RESUMEN

High-tech businesses are the driving force behind global knowledge-based economies. Academic institutions have positioned themselves to serve the high-tech industry through consulting, licensing, and university spinoffs. The awareness of commercialization strategies and building an entrepreneurial culture can help academics to efficiently transfer their inventions to the market to achieve the maximum value. Here, the concept of high-tech entrepreneurship is discussed from lab to market in technology-intensive sectors such as nanotechnology, photonics, and biotechnology, specifically in the context of lab-on-a-chip devices. This article provides strategies for choosing a commercialization approach, financing a startup, marketing a product, and planning an exit. Common reasons for startup company failures are discussed and guidelines to overcome these challenges are suggested. The discussion is supplemented with case studies of successful and failed companies. Identifying a market need, assembling a motivated management team, managing resources, and obtaining experienced mentors lead to a successful exit.


Asunto(s)
Academias e Institutos/economía , Biotecnología/economía , Dispositivos Laboratorio en un Chip/economía , Concesión de Licencias/economía , Nanotecnología/economía , Sector Privado/economía
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