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1.
Appl Radiat Isot ; 181: 110101, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35065517

RESUMEN

Improving the treatment efficiency of sludge in Alexandria, Egypt, was studied to improve the primary and secondary sludge treatment efficiency, different doses ranging from 0.25 to 6 kGy of ionizing radiation were proposed and evaluated. The scope of This study is to assess the radiation-based treatment efficiency from physical, chemical, and biological perspectives and to compare between the conventional treatment method and the radiation-based treatment technology. To evaluate the performance of each treatment system, pH, oil and greases concentrations, total solid concentrations, BOD concentrations, COD concentrations, parasites, and microorganisms were assessed in the primary and secondary samples at different radiation doses (from 0.25 to 6 KGy), and in the conventionally treated samples. Irradiation by gamma radiation with a dose ranging from 0.25 to 6 kGy was efficient in reducing some of the physical contaminants. Oil & greases, Total Solids, BOD, COD concentrations were reduced significantly (p < 0.001) in a dose-dependent manner. Either primary or secondary sludge samples, total solid reduced significantly to about one-third of control concentration at six kGy. Six kGy able to reduce the BOD and COD concentrations in the primary sludge samples to that of the treated (after sludge dewatering) samples or less respectively and saved the secondary treatment stage. In primary and secondary sludge samples culture, E. coli, Staphylococcus aureus, and Vibrio spp were isolated as heavy growth on different culture media in the samples before radiation. After exposure to increasing doses of radiation, the number of isolated organisms decreased, however, the growth of Proteus, Acinetobacter, and vipro organisms was detected but in small numbers. No growth of any organism was noted at 5 kGy. On the other hand, in the secondary sludge samples, Proteus was isolated as heavy growth before radiation and After exposure to increasing doses of radiation, Moraxella spp. organisms were detected but in small numbers. By increasing the radiation doses, the free-living ciliates were decreased in the primary and secondary sludge samples. The free-living ciliates disappeared completely at 3 kGy. In the primary and secondary sludge samples, free-living ciliates reduction efficiency at 0.25 kGy was equivalent to the conventional treatment methods. So, we can conclude that radiation technology using Gamma rays at a dose higher than 5 kGy with a dose rate of 1.095 kGy/h is an effective technology for domestic and industrial waste sludge treatment from the environmental perspective and an experimental pilot plant study is required to optimize the cost of wastewater treatment through the use of irradiation technology.


Asunto(s)
Rayos gamma , Aguas del Alcantarillado/química , Purificación del Agua/métodos , Animales , Bacterias/efectos de la radiación , Egipto , Concentración de Iones de Hidrógeno , Residuos Industriales , Aceites/efectos de la radiación , Parásitos/efectos de la radiación , Dosis de Radiación
2.
Biomed Res Int ; 2018: 8497283, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29568768

RESUMEN

The impact of ultrashort nanopulse on cellular membrane is of biological significance and thus has been studied intensively. Different from cell study, this ex vivo study aims to investigate the biological effects of nanosecond pulsed electric field (nsPEF) on an independent multimembrane parasite, human hydatid cyst, to observe the unique influence of nanopulse on macromembrane structure, permeabilization, and biochemistry. The 300 ns nsPEF was delivered on an experimental model of single human hydatid cyst ex vivo with eight different parameters. Then pathological changes during 7 days of 48 parasite cysts were followed up after nsPEF. The laminated layer, the germinal layer, the protoscolex, and cyst fluid were evaluated by the morphological, pathological, and biochemical measurements. The parameter screening found that nsPEF can damage hydatid cyst effectively when the field strength is higher than 14 kV/cm. When nsPEF is higher than 29 kV/cm, nsPEF destroy hydatid cyst completely by collapsing the germinal layer, destructing protoscolices, and exhausting the nutrition.


Asunto(s)
Equinococosis/terapia , Echinococcus/efectos de la radiación , Campos Electromagnéticos , Animales , Membrana Celular/efectos de la radiación , Equinococosis/parasitología , Equinococosis/patología , Echinococcus/patogenicidad , Humanos , Parásitos/patogenicidad , Parásitos/efectos de la radiación
3.
J Invertebr Pathol ; 136: 68-73, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-26970260

RESUMEN

Bumblebees are ecologically and economically important pollinators, and the value of bumblebees for crop pollination has led to the commercial production and exportation/importation of colonies on a global scale. Commercially produced bumblebee colonies can carry with them infectious parasites, which can both reduce the health of the colonies and spillover to wild bees, with potentially serious consequences. The presence of parasites in commercially produced bumblebee colonies is in part because colonies are reared on pollen collected from honey bees, which often contains a diversity of microbial parasites. In response to this threat, part of the industry has started to irradiate pollen used for bumblebee rearing. However, to date there is limited data published on the efficacy of this treatment. Here we examine the effect of gamma irradiation and an experimental ozone treatment on the presence and viability of parasites in honey bee pollen. While untreated pollen contained numerous viable parasites, we find that gamma irradiation reduced the viability of parasites in pollen, but did not eliminate parasites entirely. Ozone treatment appeared to be less effective than gamma irradiation, while an artificial pollen substitute was, as expected, entirely free of parasites. The results suggest that the irradiation of pollen before using it to rear bumblebee colonies is a sensible method which will help reduce the incidence of parasite infections in commercially produced bumblebee colonies, but that further optimisation, or the use of a nutritionally equivalent artificial pollen substitute, may be needed to fully eliminate this route of disease entry into factories.


Asunto(s)
Abejas/parasitología , Polen/parasitología , Polen/efectos de la radiación , Esterilización/métodos , Animales , Rayos gamma , Parásitos/efectos de la radiación
4.
Ann Bot ; 117(3): 521-31, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26832961

RESUMEN

BACKGROUND AND AIMS: There have been very few studies investigating the influence of light on the effects of hemiparasitic plants on their hosts, despite the fact that hemiparasites are capable of photosynthesis but also access carbon (C) from their host. In this study we manipulated light availability to limit photosynthesis in an established hemiparasite and its hosts, and determined whether this affected the parasite's impact on growth and performance of two different hosts. We expected that limiting light and reducing autotrophic C gain in the parasite (and possibly increasing its heterotrophic C gain) would lead to an increased impact on host growth and/or host photosynthesis in plants grown in low (LL) relative to high light (HL). METHODS: The Australian native host Leptospermum myrsinoides and the introduced host Ulex europaeus were either infected or not infected with the native stem hemiparasite Cassytha pubescens and grown in either HL or LL. Photosynthetic performance, nitrogen status and growth of hosts and parasite were quantified. Host water potentials were also measured. KEY RESULTS: In situ midday electron transport rates (ETRs) of C. pubescens on both hosts were significantly lower in LL compared with HL, enabling us to investigate the impact of the reduced level of parasite autotrophy on growth of hosts. Despite the lower levels of photosynthesis in the parasite, the relative impact of infection on host biomass was the same in both LL and HL. In fact, biomass of L. myrsinoides was unaffected by infection in either HL or LL, while biomass of U. europaeus was negatively affected by infection in both treatments. This suggests that although photosynthesis of the parasite was lower in LL, there was no additional impact on host biomass in LL. In addition, light did not affect the amount of parasite biomass supported per unit host biomass in either host, although this parameter was slightly lower in LL than HL for U. europaeus (P = 0·073). We also found no significant enhancement of host photosynthesis in response to infection in either host, regardless of light treatment. CONCLUSIONS: Despite lower photosynthetic rates in LL, C. pubescens did not increase its dependency on host C to the point where it affected host growth or photosynthesis. The impact of C. pubescens on host growth would be similar in areas of high and low light availability in the field, but the introduced host is more negatively affected by infection.


Asunto(s)
Interacciones Huésped-Parásitos/efectos de la radiación , Especies Introducidas , Luz , Parásitos/fisiología , Tallos de la Planta/parasitología , Tallos de la Planta/efectos de la radiación , Análisis de Varianza , Animales , Biomasa , Transporte de Electrón/efectos de la radiación , Leptospermum/parasitología , Leptospermum/efectos de la radiación , Nitrógeno/metabolismo , Parásitos/crecimiento & desarrollo , Parásitos/efectos de la radiación , Fotosíntesis/efectos de la radiación , Brotes de la Planta/fisiología , Brotes de la Planta/efectos de la radiación , Estomas de Plantas/fisiología , Estomas de Plantas/efectos de la radiación , Ulex/parasitología , Ulex/efectos de la radiación
5.
New Phytol ; 182(4): 965-974, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19323792

RESUMEN

Holoparasitic plants such as Orobanche spp. have lost their photosynthetic ability, so photoresponses to optimize photosynthesis are not necessary in these plants. Photoresponses are also involved in the regulation of plant development but the photoresponses of holoparasites have not been characterized in detail. In this study, the phytochrome (phy)-related photoresponse of Orobanche minor was investigated. Its photoreceptor, phytochrome A (OmphyA), was also characterized. Light effects on germination, shoot elongation, anthocyanin biosynthesis, and OmphyA expression and subcellular localization were analyzed. Red light (R):far-red light (FR) reversible inhibition of O. minor seed germination demonstrated that phy-mediated responses are retained in this holoparasite. Shoot elongation was inhibited by FR but not by R. This pattern is unique among known patterns of plant photoresponses. Additionally, molecular analysis showed that OmphyA is able to respond to the light signals. Interestingly, the unique pattern of photoresponses in O. minor seems to have been modified for adaptation to its parasitic life cycle. We hypothesize that this alteration has resulted from the loss or alteration of some phy-signaling components. Elucidation of altered components in phy signaling in this parasite will provide useful information not only about its physiological characteristics but also about general plant photoreception systems.


Asunto(s)
Orobanche/metabolismo , Parásitos/metabolismo , Fitocromo A/metabolismo , Animales , Antocianinas/biosíntesis , Western Blotting , Regulación de la Expresión Génica de las Plantas , Germinación/efectos de la radiación , Proteínas Fluorescentes Verdes/metabolismo , Luz , Orobanche/genética , Orobanche/efectos de la radiación , Parásitos/genética , Parásitos/efectos de la radiación , Fotoperiodo , Fitocromo A/genética , Brotes de la Planta/genética , Brotes de la Planta/crecimiento & desarrollo , Brotes de la Planta/efectos de la radiación , Transporte de Proteínas/efectos de la radiación , Protoplastos/metabolismo , Protoplastos/efectos de la radiación , Semillas/crecimiento & desarrollo , Semillas/efectos de la radiación , Fracciones Subcelulares/metabolismo , Fracciones Subcelulares/efectos de la radiación , Factores de Tiempo
6.
Transfusion ; 46(7): 1168-77, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16836564

RESUMEN

BACKGROUND: The INTERCEPT Blood System, a photochemical treatment (PCT) process, has been developed to inactivate pathogens in platelet concentrates. These studies evaluated the efficacy of PCT to inactivate pathogens in plasma and the effect of PCT on plasma function. STUDY DESIGN AND METHODS: Jumbo (600 mL) plasma units were inoculated with high titers of test pathogens and treated with 150 micromol per L amotosalen and 3 J per cm(2) long-wavelength ultraviolet light. The viability of each pathogen before and after treatment was measured with biological assays. Plasma function was evaluated through measurement of coagulation factors and antithrombotic protein activities. RESULTS: The levels of inactivation expressed as log-reduction were as follows: cell-free human immunodeficiency virus-1 (HIV-1), greater than 6.8; cell-associated HIV-1, greater than 6.4; human T-lymphotropic virus-I (HTLV-I), 4.5; HTLV-II, greater than 5.7; hepatitis B virus (HBV) and hepatitis C virus, greater than 4.5; duck HBV, 4.4 to 4.5; bovine viral diarrhea virus, 6.0; severe acute respiratory syndrome coronavirus, 5.5; West Nile virus, 6.8; bluetongue virus, 5.1; human adenovirus 5, 6.8; Klebsiella pneumoniae, greater than 7.4; Staphylococcus epidermidis and Yersinia enterocolitica, greater than 7.3; Treponema pallidum, greater than 5.9; Borrelia burgdorferi, greater than 10.6; Plasmodium falciparum, 6.9; Trypanosoma cruzi, greater than 5.0; and Babesia microti, greater than 5.3. Retention of coagulation factor activity after PCT was expressed as the proportion of pretreatment (baseline) activity. Retention was 72 to 73 percent of baseline fibrinogen and Factor (F)VIII activity and 78 to 98 percent for FII, FV, FVII, F IX, FX, FXI, FXIII, protein C, protein S, antithrombin, and alpha2-antiplasmin. CONCLUSION: PCT of plasma inactivated high levels of a wide range of pathogens while maintaining adequate coagulation function. PCT has the potential to reduce the risk of transfusion-transmitted diseases in patients requiring plasma transfusion support.


Asunto(s)
Patógenos Transmitidos por la Sangre/efectos de la radiación , Transmisión de Enfermedad Infecciosa/prevención & control , Fotoquímica/métodos , Plasma/virología , Rayos Ultravioleta , Animales , Bacterias/efectos de la radiación , Coagulación Sanguínea/efectos de la radiación , Factores de Coagulación Sanguínea/análisis , Factores de Coagulación Sanguínea/efectos de la radiación , Eucariontes/efectos de la radiación , Furocumarinas/farmacología , Humanos , Parásitos/efectos de la radiación , Plasma/efectos de la radiación , Inactivación de Virus/efectos de la radiación , Virus/efectos de la radiación
9.
Zentralbl Bakteriol Orig B ; 161(1): 61-71, 1975 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-1189798

RESUMEN

The destroying effect of ionizing radiation on parasitic resistant stages in sludge has been tested. Suitable for that process is an electron beam accelerator which will be provided with energy from the electric power supply network which can be switched on and off according to the requirements. Such modern utilities have an enormous beam capacity and a high operating safety. The process is working according to the continuous flow principle and at room temperature. In a series of 13 experiments the effect of different doses has been tested. A dose of 480 kRad (accelerating voltage; 400 kV, beam current; 10 mA, irradiation time: 24 sec.) can easely obtained in practical work and is economically acceptable. By these means approximately 97% of the following parasitic stages have been destroyed: undeveloped eggs of Ascaris suum, Trichuris suis, Fasciola hepatica and gastrointestinal strongylids of pigs, embryonated eggs of Capillaria obsignata and probably of Taenia spec. A few third-stage larvae of Oesophagostomum (Strongylidae) of pigs survived even 108 sec of irradiation; however, they did not develop to maturity in the definitive host. Approximately 25% of the sporulated oocysts of Eimeria renella were still infective after 108 sec of irradiation.


Asunto(s)
Parásitos/efectos de la radiación , Efectos de la Radiación , Aguas del Alcantarillado , Ascaris/efectos de la radiación , Capillaria/efectos de la radiación , Relación Dosis-Respuesta en la Radiación , Eimeria/efectos de la radiación , Fasciola hepatica/efectos de la radiación , Humanos , Oesophagostomum/efectos de la radiación , Strongyloidea/efectos de la radiación , Taenia/efectos de la radiación , Trichuris/efectos de la radiación
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