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1.
PLoS One ; 17(12): e0276109, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36548254

RESUMEN

The restoration of the once abundant Cisco (Coregonus artedi) is a management interest across the Laurentian Great Lakes. To inform the restoration, we (1) described historical distributions of Cisco and (2) explored whether non-indigenous Rainbow Smelt (Osmerus mordax) and Alewife (Alosa pseudoharengus) played a role in the decline of Cisco populations across the upper Great Lakes (i.e., Lakes Superior, Michigan, and Huron). Our source data were collected from fishery-independent surveys conducted by the U.S. Fish and Wildlife Service's research vessel R/V Cisco in 1952-1962. By analyzing data collected by gill-net surveys, we confirmed the importance of embayment and shallow-water habitats to Cisco. We found that Cisco was abundant in Whitefish Bay and Keweenaw Bay, Lake Superior, and in Green Bay, Lake Michigan, but we also found a sign of Cisco extirpation in Saginaw Bay, Lake Huron. Our results also showed that Ciscoes generally stayed in waters <80 m in bottom depth throughout the year. However, a substantial number of Ciscoes stayed in very deep waters (>150 m in bottom depth) in summer and fall in Lake Michigan, although we cannot exclude the possibility that these Ciscoes had hybridized with the other Coregonus species. By comparing complementary data collected from bottom-trawl surveys, we concluded that the spatiotemporal overlap between Rainbow Smelt and Cisco likely occurred across the upper Great Lakes throughout 1952-1962. These data were consistent with the hypothesis that Rainbow Smelt played a role in the decline of Cisco populations across the upper Great Lakes in the period. We also found that the spatiotemporal overlap between Alewife and Cisco likely occurred only in Saginaw Bay in fall 1956 and in Lake Michigan after 1960. Thus, any potential recovery of Cisco after the 1950s could have been inhibited by Alewife in Lakes Michigan and Huron.


Asunto(s)
Osmeriformes , Salmonidae , Animales , Lagos , Ecosistema , Michigan , Great Lakes Region
2.
Nat Commun ; 11(1): 2526, 2020 05 20.
Artículo en Inglés | MEDLINE | ID: mdl-32433562

RESUMEN

Globally, our knowledge on lake fisheries is still limited despite their importance to food security and livelihoods. Here we show that fish catches can respond either positively or negatively to climate and land-use changes, by analyzing time-series data (1970-2014) for 31 lakes across five continents. We find that effects of a climate or land-use driver (e.g., air temperature) on lake environment could be relatively consistent in directions, but consequential changes in a lake-environmental factor (e.g., water temperature) could result in either increases or decreases in fish catch in a given lake. A subsequent correlation analysis indicates that reductions in fish catch was less likely to occur in response to potential climate and land-use changes if a lake is located in a region with greater access to clean water. This finding suggests that adequate investments for water-quality protection and water-use efficiency can provide additional benefits to lake fisheries and food security.


Asunto(s)
Explotaciones Pesqueras , Lagos/química , Animales , Cambio Climático , Ecosistema , Peces/crecimiento & desarrollo , Humanos , Temperatura , Calidad del Agua
3.
PLoS One ; 15(4): e0231420, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32267898

RESUMEN

With the global-scale loss of biodiversity, current restoration programs have been often required as part of conservation plans for species richness and ecosystem integrity. The restoration of pelagic-oriented cisco (Coregonus artedi) has been an interest of Lake Michigan managers because it may increase the diversity and resilience of the fish assemblages and conserve the integrity of the ecosystems in a changing environment. To inform restoration, we described historical habitat use of cisco by analyzing a unique fishery-independent dataset collected in 1930-1932 by the U.S. Bureau of Fisheries' first research vessel Fulmar and a commercial catch dataset reported by the State of Michigan in the same period, both based on gear fished on the bottom. Our results confirmed that the two major embayments, Green Bay and Grand Traverse Bay, were important habitats for cisco and suggest that the Bays were capable of supporting cisco to complete its entire life cycle in the early 20th century as there was no lack of summer feeding and fall spawning habitats. Seasonally, our results showed that cisco stayed in nearshore waters in spring, migrated to offshore waters in summer, and then migrated back to nearshore waters in fall. The results also suggest that in summer, most ciscoes were in waters with bottom depths of 20-70 m, but the highest cisco density occurred in waters with a bottom depth around 40 m. We highlight the importance of embayment habitats to cisco restoration and the seasonal migration pattern of cisco identified in this study, which suggests that a restored cisco population can diversify the food web by occupying different habitats from the exotic fishes that now dominate the pelagic waters of Lake Michigan.


Asunto(s)
Ecosistema , Peces/fisiología , Lagos , Animales , Biodiversidad , Bases de Datos Factuales , Explotaciones Pesqueras/historia , Historia del Siglo XX , Estaciones del Año
4.
Cytotherapy ; 18(7): 911-24, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27260210

RESUMEN

BACKGROUND AIMS: Pooled human platelet lysate (HPL) is becoming the new gold standard as supplement for ex vivo cell culture for clinical protocols. However, the risk of pathogen contamination of HPL increases with the platelet pool size. We hypothesized that hollow fiber anion exchange membrane chromatography using QyuSpeed D (QSD) could remove resistant and untested bloodborne pathogens, such as parvoviruses and prions, from HPL-supplemented growth media without substantially affecting their capacity to support ex vivo cell expansion. METHODS: Frozen or thawed platelet concentrates were serum-converted and centrifuged for obtaining HPL that was added to various growth media (ca. 100 mL), filtered through a 0.6-mL QSD membrane and characterized for proteins, growth factors and chemical composition. Capacity to expand Chinese hamster ovary, periodontal ligament, gingival fibroblast cells and Wharton's jelly mesenchymal stromal cells was studied. Removal of porcine parvovirus (PPV) and of the 263K prion strain of hamster-adapted scrapie was studied by spiking experiments following international guidelines. RESULTS: QSD had minimal impact on HPL-supplemented medium composition in proteins, growth factors and chemical content, nor capacity to expand and differentiate cells. In addition, QSD could remove ≥5.58 log10 [TCID50/mL] and ≥3.72 log10 of PPV and the 263K prion, respectively. CONCLUSIONS: QSD hollow fiber chromatography can be used to improve the virus and prion safety of HPL-supplemented media to safely expand cells for clinical protocols. These data bring new perspectives for increasingly safer use of pooled HPL in cell therapy and regenerative medicine applications.


Asunto(s)
Plaquetas/citología , Plaquetas/virología , Parvovirus/aislamiento & purificación , Priones/aislamiento & purificación , Animales , Células CHO , Recuento de Células , Técnicas de Cultivo de Célula , Proliferación Celular , Supervivencia Celular , Cricetinae , Cricetulus , Medios de Cultivo , Fibroblastos/citología , Encía/citología , Humanos , Células Madre Mesenquimatosas/citología , Ligamento Periodontal/citología , Sus scrofa , Gelatina de Wharton/citología
5.
Nanomedicine (Lond) ; 9(1): 77-87, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23799985

RESUMEN

AIM: We developed biodegradable, lidocaine-embedded poly([D,L]-lactide-co-glycolide) nanofibers for epidural analgesia to reduce the severe pain in rats after laminectomies. MATERIALS & METHODS: Nanofibers were prepared by an electrospinning process and were introduced into the epidural space of rats after laminectomy. The lidocaine concentration, postoperative bodyweight change and amount of food/water intake were monitored to evaluate the analgesic effectiveness of the drug-eluting nanofibers. RESULTS: It was demonstrated that the nanofibers provided a sustained release of lidocaine for more than 2 weeks, and the local pharmaceutical concentration was much higher than the concentration in plasma. Rats that received laminectomies without nanofibers exhibited the greatest bodyweight reduction. The food/water intake and activity performance were significantly higher in rats receiving laminectomies with nanofibers than in rats without nanofibers. CONCLUSION: The results of this study suggest that the lidocaine-loaded nanofibers can provide an easy, practical and safe means of achieving effective postlaminectomy analgesia.


Asunto(s)
Plásticos Biodegradables/química , Sistemas de Liberación de Medicamentos , Lidocaína/administración & dosificación , Nanofibras/administración & dosificación , Animales , Dioxanos/administración & dosificación , Dioxanos/química , Espacio Epidural , Humanos , Laminectomía , Lidocaína/química , Nanofibras/química , Ratas
6.
ACS Chem Neurosci ; 4(9): 1314-21, 2013 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-23815098

RESUMEN

Successful treatment of a brain infection requires aspiration of the pus or excision of the abscess, followed by long-term (usually 4-8 weeks) parenteral antibiotic treatment. Local antibiotic delivery using biodegradable drug-impregnated carriers is effective in treating postoperative infections, thereby reducing the toxicity associated with parenteral antibiotic treatment and the expense involved with long-term hospitalization. We have developed vancomycin-loaded, biodegradable poly[lactic-co-glycol acid] nanofibrous membranes for the sustainable delivery of vancomycin to the brain tissue of rats by using the electrospinning technique. A high-performance liquid chromatography assay was employed to characterize the in vitro and in vivo release behaviors of pharmaceuticals from the membranes. The experimental results suggested that the biodegradable nanofibers can release high concentrations of vancomycin for more than 8 weeks in the cerebral cavity of rats. Furthermore, the membranes can cover the wall of the cavity after the removal of abscess more completely and achieve better drug delivery without inducing adverse mass effects in the brain. Histological examination also showed no inflammation reaction of the brain tissues. By adopting the biodegradable, nanofibrous drug-eluting membranes, we will be able to achieve long-term deliveries of various antibiotics in the cerebral cavity to enhance the therapeutic efficacy of cerebral infections.


Asunto(s)
Implantes Absorbibles , Antibacterianos/administración & dosificación , Absceso Encefálico/tratamiento farmacológico , Encéfalo/efectos de los fármacos , Ácido Láctico , Membranas Artificiales , Nanofibras , Ácido Poliglicólico , Vancomicina/administración & dosificación , Absorción , Animales , Antibacterianos/efectos adversos , Antibacterianos/uso terapéutico , Encéfalo/ultraestructura , Cromatografía Líquida de Alta Presión , Terapia Combinada , Portadores de Fármacos , Evaluación Preclínica de Medicamentos , Implantes de Medicamentos , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Porosidad , Distribución Aleatoria , Ratas , Vancomicina/efectos adversos , Vancomicina/uso terapéutico , Cicatrización de Heridas
7.
Sensors (Basel) ; 13(5): 6636-50, 2013 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-23686142

RESUMEN

The current trend of the civil aviation technology is to modernize the legacy air traffic control (ATC) system that is mainly supported by many ground based navigation aids to be the new air traffic management (ATM) system that is enabled by global positioning system (GPS) technology. Due to the low receiving power of GPS signal, it is a major concern to aviation authorities that the operation of the ATM system might experience service interruption when the GPS signal is jammed by either intentional or unintentional radio-frequency interference. To maintain the normal operation of the ATM system during the period of GPS outage, the use of the current radar system is proposed in this paper. However, the tracking performance of the current radar system could not meet the required performance of the ATM system, and an enhanced tracking algorithm, the interacting multiple model and probabilistic data association filter (IMMPDAF), is therefore developed to support the navigation and surveillance services of the ATM system. The conventional radar tracking algorithm, the nearest neighbor Kalman filter (NNKF), is used as the baseline to evaluate the proposed radar tracking algorithm, and the real flight data is used to validate the IMMPDAF algorithm. As shown in the results, the proposed IMMPDAF algorithm could enhance the tracking performance of the current aviation radar system and meets the required performance of the new ATM system. Thus, the current radar system with the IMMPDAF algorithm could be used as an alternative system to continue aviation navigation and surveillance services of the ATM system during GPS outage periods.

8.
Expert Opin Drug Deliv ; 10(7): 879-88, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23289446

RESUMEN

OBJECTIVE: Glioblastoma multiforme (GBM) is the most common and most aggressive malignant primary brain tumor in humans. The only interstitial chemotherapy pharmaceutical approved to date for GBM treatment is the Gliadel® wafer. Despite the safety and efficacy of this approach that have been demonstrated in patients undergoing resection of both newly diagnosed and recurrent malignant gliomas, the wafer provides an effective release of the anticancer 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) for only 5 days. METHODS: In this study, the authors developed biodegradable poly[(d,l)-lactide-co-glycolide] nanofibrous membranes via electrospinning that provided a sustained release of BCNU. An elution method and a HPLC assay were employed to characterize the in vitro and in vivo release behaviors of pharmaceuticals from the electrospun membranes. RESULTS: The experimental results show that the biodegradable, nanofibrous membranes released high concentrations of BCNU for more than 6 weeks in the cerebral cavity of rats. Furthermore, the membranes can better conform to the geometry of the brain tissue and can cover more completely the tissue after the removal of tumors, achieving better drug transport without interfering with the normal function of the brain. Histological examination showed no obvious inflammation reactions of the brain tissues. CONCLUSION: Adopting the electrospinning technique will help in manufacturing biodegradable, nanofibrous membranes for the long-term deliveries of various anticancer drugs in the cerebral cavity, which will further enhance the therapeutic efficacy of GBM treatment.


Asunto(s)
Antineoplásicos Alquilantes/farmacocinética , Materiales Biocompatibles/química , Carmustina/farmacocinética , Corteza Cerebral/metabolismo , Portadores de Fármacos/química , Implantes de Medicamentos , Ácido Láctico/química , Ácido Poliglicólico/química , Implantes Absorbibles , Animales , Antineoplásicos Alquilantes/administración & dosificación , Disponibilidad Biológica , Transporte Biológico , Barrera Hematoencefálica/efectos de los fármacos , Neoplasias Encefálicas/tratamiento farmacológico , Carmustina/administración & dosificación , Química Farmacéutica , Cromatografía Líquida de Alta Presión , Nanofibras , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Ratas , Ratas Wistar
9.
J Biomed Mater Res A ; 94(2): 489-98, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20186774

RESUMEN

In this study, we modified poly(ethylene-co-vinyl alcohol) (EVAL) membranes by the covalent bonding of diamines via epoxidation of surface hydroxyl groups of EVAL to analyze the effect of immobilized diamines with different carbon chain length on the cultured cerebellar granule neurons. Morphological studies showed that neurons seeded on the diamine-immobilized EVAL membrane were able to survive and regenerate with formation of an extensive neuritic network. Furthermore, cultured neurons showed that the presence of diamine with different carbon chain length was able to effectively regulate the neuron adhesion, migration, aggregation, and neurite growth pattern, but mediated neuronal activity with equal efficacy. The short-chain amine stimulated neuron migration, aggregation, and neurite fasciculation, whereas the long carbon chain diamine maintained single neuron distribution with the defasciculated feature of the neurite. Although it is known that positively charged amine molecules can interact directly with cell surface proteoglycans to mediate cell attachment, this study further demonstrated that the terminal primary amine with different carbon chain length is involved in mediating cell-substrate interaction to further regulate neuron aggregation and neurite fasciculation. This indicates a delicate interaction of neuron with the immobilized diamine molecules on the EVAL membrane surface. This work is encouraging because the diamine- immobilized EVAL membranes can be applied for the establishment of different neural culture systems useful for future investigations of neuron biology under in vitro conditions.


Asunto(s)
Alcoholes/química , Diaminas/química , Neuritas/fisiología , Neuronas/fisiología , Polietilenos/química , Animales , Adhesión Celular/fisiología , Movimiento Celular/fisiología , Forma de la Célula , Células Cultivadas , Neuronas/citología , Ratas , Ratas Wistar , Propiedades de Superficie
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