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1.
Avian Pathol ; 52(5): 351-361, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37439655

RESUMEN

Avian influenza H9N2 is one of the most commonly circulating viruses in numerous Egyptian poultry farms. The Asian lineage H9N2 exhibits an immunosuppressive effect, and its pathogenicity is amplified when it co-infects with other pathogens, especially with the immunosuppressive infectious bursal disease virus (IBDV), resulting in increased mortality rates. Both vaccines and field infection can exacerbate the pathogenicity of H9N2, particularly in the bursa of Fabricius, causing more significant lymphoid depletion. To comprehend the impact of the IBD vaccine on the viral and pathogenic effect of H9N2 infection in specific pathogen-free chicks (SPF), the experiment was designed as four groups; group 1 served as the negative control, group 2 received (228E) IBD vaccine, group 3 was challenged with H9N2, and group-4 was vaccinated by the IBD vaccine then challenged with H9N2. The clinical signs, relative immune organs weights and histopathological lesion scores were recorded. The tracheal and cloacal H9N2 viral shedding were also measured. Group 4 exhibited a significant decrease (P ≤ 0.05) in the relative bursal weight and an increase in the bursal lesion score when compared with groups 1 and 3 at 4 and 8 days post-challenge (dpc). The tracheal lesion score of group-4 recorded a significant increase when compared with groups 1 and 3. The renal lesion score of group 4 achieved a significant increase when compared with 1 and 3 at 8 dpc. Also, group 4 recorded a significant increase in H9N2 shedding in comparison with groups 1 and 3. Consequently, our study concluded that routine vaccination with the IBD intermediate plus vaccine exacerbates the silent infection of H9N2 resulting in outbreaks.


Asunto(s)
Infecciones por Birnaviridae , Virus de la Enfermedad Infecciosa de la Bolsa , Subtipo H9N2 del Virus de la Influenza A , Gripe Aviar , Enfermedades de las Aves de Corral , Vacunas Virales , Animales , Pollos , Aves de Corral , Vacunas Atenuadas , Vacunas Virales/efectos adversos , Infecciones por Birnaviridae/veterinaria , Infecciones por Birnaviridae/prevención & control
2.
BMC Plant Biol ; 22(1): 14, 2022 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-34979930

RESUMEN

BACKGROUND: Unreduced gametes, a driving force in the widespread polyploidization and speciation of flowering plants, occur relatively frequently in interspecific or intergeneric hybrids. Studies of the mechanisms leading to 2n gamete formation, mainly in the wheat tribe Triticeae have shown that unreductional meiosis is often associated with chromosome asynapsis during the first meiotic division. The present study explored the mechanisms of meiotic nonreduction leading to functional unreduced gametes in an interspecific Trifolium (clover) hybrid with three sub-genomes from T. ambiguum and one sub-genome from T. occidentale. RESULTS: Unreductional meiosis leading to 2n gametes occurred when there was a high frequency of asynapsis during the first meiotic division. In this hybrid, approximately 39% of chromosomes were unpaired at metaphase I. Within the same cell at anaphase I, sister chromatids of univalents underwent precocious separation and formed laggard chromatids whereas paired chromosomes segregated without separation of sister chromatids as in normal meiosis. This asynchrony was frequently accompanied by incomplete or no movement of chromosomes toward the poles and restitution leading to unreduced chromosome constitutions. Reductional meiosis was restored in progeny where asynapsis frequencies were low. Two progeny plants with approximately 5 and 7% of unpaired chromosomes at metaphase I showed full restoration of reductional meiosis. CONCLUSIONS: The study revealed that formation of 2n gametes occurred when asynapsis (univalent) frequency at meiosis I was high, and that normal gamete production was restored in the next generation when asynapsis frequencies were low. Asynapsis-dependent 2n gamete formation, previously supported by evidence largely from wheat and its relatives and grasshopper, is also applicable to hybrids from the dicotyledonous plant genus Trifolium. The present results align well with those from these widely divergent organisms and strongly suggest common molecular mechanisms involved in unreduced gamete formation.


Asunto(s)
Células Germinativas de las Plantas/crecimiento & desarrollo , Meiosis , Trifolium/crecimiento & desarrollo , Células Germinativas de las Plantas/metabolismo , Hibridación Genética , Trifolium/genética
3.
BMC Plant Biol ; 19(1): 438, 2019 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-31640569

RESUMEN

BACKGROUND: Trifolium ambiguum occurs as a 2x, 4x, 6x polyploid series in W Asia. The 6x form is the most agronomically desirable, having strong rhizomatous spread and drought tolerance. These traits would be potentially very valuable if they could be transferred to white clover (T. repens) which is the most important agronomic clover species. However, to-date, no fertile interspecific hybrids with 6x T. ambiguum are available. Previously, 2x T. occidentale from W Europe has produced synthetic fertile hybrids with both 2x and 4x T. ambiguum and these were inter-fertile with white clover. Here we ask whether 2x T. occidentale can form fertile hybrids with 6x T. ambiguum and act as a genetic bridge to white clover and bring these species together as part of a common gene pool. RESULTS: Ten verified F1 (6x T. ambiguum x 2x T. occidentale) hybrids were produced by embryo rescue and seven were studied further. All four investigated for chromosome number were 2n = 4x = 32 and FISH confirmed the expected 21 T. ambiguum and 8 T. occidentale chromosomes. Hybrid fertility was extremely low but 2n female gametes functioned with white clover pollen to produce seeds. Derived plants were confirmed using FISH and were successfully backcrossed to white clover to produce partially fertile breeding populations. CONCLUSIONS: Although T. occidentale and 6x T. ambiguum are widely separated by geography and ecological adaptation they have maintained enough genomic affinity to produce partially fertile hybrids. Inter-fertility of the hybrids with allotetraploid T. repens showed that T. occidentale can provide a genetic bridge between 6x T. ambiguum and white clover to produce plants with new phenotypes combining the traits of all three species. Use of this information should enable potentially valuable stress tolerance traits from 6x T. ambiguum to be used in white clover breeding for the first time.


Asunto(s)
Genoma de Planta/genética , Trifolium/genética , Genotipo , Hibridación Genética , Fenotipo , Fitomejoramiento , Poliploidía , Semillas/genética
4.
Cutan Ocul Toxicol ; 36(4): 387-392, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28351163

RESUMEN

BACKGROUND: Chronic spontaneous urticaria (CSU) is a common dermatological condition defined by the sudden occurrence of daily wheals and pruritus for at least six weeks. Multifactorial origin is suggested such as oxidative stress. This latter may play a double role as a trigger and remnant agent. OBJECTIVES: The first aim of this study is to investigate antioxidant status, inflammatory proteins, hematologic counts and clinical assessment in CSU patients. The second aim is to evaluate the effect of a first-line treatment: desloratadine 5 mg/d on these different parameters. PATIENTS AND METHODS: This study enrolled 30 CSU patients and same number of controls. We assessed the urticaria activity score (UAS), total antioxidant status (TAS), glutathione S-transferase (GST), superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT), albumin, alpha1, alpha2, beta1 beta2, gamma globulins, c-reactive protein (CRP) and hematologic numeration. RESULTS: At baseline alpha1, alpha2, beta1, beta2, gamma globulins, CRP, SOD activity, leukocytes and basophils were significantly higher in patients versus controls (p < 0.05). TAS, GST, CAT, GPx and albumin were significantly low in patients versus controls (p < 0.05). After treatment, TAS, GST and GPx were significantly increased in patients versus patients before treatment (p < 0.001). SOD, alpha1, alpha2, beta1, beta2, gamma globulins, CRP, albumin, leukocytes and basophils were significantly decreased after treatment versus before treatment (p < 0.05). A significant correlation between CRP and UAS (r = 0.3; p = 0.011) was noted. UAS assessment revealed the efficacy of 30 d-antihistaminic treatment. CONCLUSIONS: Desloratadine exerted anti-inflammatory and antioxidant effects on CSU patients revealed by CRP. Patients' remission was synergistic to CRP attenuation emphasizing CRP relevance for CSU clinical assessment.


Asunto(s)
Antiinflamatorios/uso terapéutico , Antioxidantes/uso terapéutico , Proteína C-Reactiva/análisis , Loratadina/análogos & derivados , Urticaria/tratamiento farmacológico , Adulto , Antiinflamatorios/farmacología , Antioxidantes/farmacología , Catalasa/sangre , Enfermedad Crónica , Femenino , Glutatión Peroxidasa/sangre , Glutatión Transferasa/sangre , Antagonistas de los Receptores Histamínicos H1 no Sedantes/farmacología , Antagonistas de los Receptores Histamínicos H1 no Sedantes/uso terapéutico , Humanos , Loratadina/farmacología , Loratadina/uso terapéutico , Masculino , Persona de Mediana Edad , Índice de Severidad de la Enfermedad , Superóxido Dismutasa/sangre , Túnez , Urticaria/sangre , Urticaria/patología , Adulto Joven
5.
BMC Genomics ; 17(1): 977, 2016 11 25.
Artículo en Inglés | MEDLINE | ID: mdl-27887567

RESUMEN

BACKGROUND: The unambiguous identification of individual chromosomes is a key part of the genomic characterization of any species. In this respect, the development and application of chromosome banding techniques has revolutionised mammalian and especially, human genomics. However, partly because of the traditional use of chromosome squash preparations, consistent fluorescence banding has rarely been achieved in plants. Here, successful fluorescence chromosome banding has been achieved for the first time in perennial ryegrass (Lolium perenne), a forage and turf grass with a large genome and a symmetrical karyotype with chromosomes that are difficult to distinguish. RESULTS: Based on flame-dried chromosome preparations instead of squashes, a simple fluorescence Q-banding technique using quinacrine mustard, unambiguously identified each chromosome and enabled the development of a banded karyotype and ideogram of the species. This Q-banding technique was also shown to be compatible with sequential FISH mapping enabling labelled genes and molecular markers to be precisely assigned to specific cytogenetic bands. A technique for DAPI-banding, which gave a similar pattern to Q-banding, was also introduced. This was compatible with FISH mapping and was used to anchor a single copy gene from an earlier mapped linkage group of L. perenne, thus providing a step towards integration of the genetic and cytogenetic maps. CONCLUSIONS: By enabling the allocation of genes mapped by other methods to physically identified chromosome positions, this work will contribute to a better understanding of genomic structures and functions in grasses.


Asunto(s)
Bandeo Cromosómico , Mapeo Cromosómico , Hibridación Fluorescente in Situ , Lolium/genética , Cariotipo
6.
Sci Rep ; 13(1): 10964, 2023 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-37415084

RESUMEN

This study investigates the physical and optical properties as well as the radiation shielding capacity of polyvinyl chloride (PVC) loaded with x% of bismuth vanadate (BiVO4) (x = 0, 1, 3, and 6 wt%). As a non-toxic nanofiller, the designed materials are low-cost, flexible, and lightweight plastic to replace traditional lead, which is toxic and dense. XRD patterns and FTIR spectra demonstrated a successful fabrication and complexation of nanocomposite films. In addition, the particle size, morphology, and elemental composition of the BiVO4 nanofiller were demonstrated through the utilization of TEM, SEM, and EDX spectra. The MCNP5 simulation code assessed the gamma-ray shielding effectiveness of four PVC + x% BiVO4 nanocomposites. The obtained mass attenuation coefficient data of the developed nanocomposites were comparable to the theoretical calculation performed with Phy-X/PSD software. Moreover, the initial stage in the computation of various shielding parameters, such as half-value layer, tenth value layer, and mean free path, besides the simulation of linear attenuation coefficient. The transmission factor declines while radiation protection efficiency increases with an increase in the proportion of BiVO4 nanofiller. Further, the current investigation seeks to evaluate the thickness equivalent (Xeq), effective atomic number (Zeff), and effective electron density (Neff) values as a function of the concentration of BiVO4 in a PVC matrix. The results obtained from the parameters indicate that incorporating BiVO4 into PVC can be an effective strategy for developing sustainable and lead-free polymer nanocomposites, with potential uses in radiation shielding applications.


Asunto(s)
Nanocompuestos , Protección Radiológica , Humanos , Simulación por Computador , Atención Odontológica , Rayos gamma
7.
BMC Plant Biol ; 12: 55, 2012 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-22530692

RESUMEN

BACKGROUND: White clover (Trifolium repens) is a ubiquitous weed of the temperate world that through use of improved cultivars has also become the most important legume of grazed pastures world-wide. It has long been suspected to be allotetraploid, but the diploid ancestral species have remained elusive. Putative diploid ancestors were indicated by DNA sequence phylogeny to be T. pallescens and T. occidentale. Here, we use further DNA evidence as well as a combination of molecular cytogenetics (FISH and GISH) and experimental hybridization to test the hypothesis that white clover originated as a hybrid between T. pallescens and T. occidentale. RESULTS: T. pallescens plants were identified with chloroplast trnL intron DNA sequences identical to those of white clover. Similarly, T. occidentale plants with nuclear ITS sequences identical to white clover were also identified. Reciprocal GISH experiments, alternately using labeled genomic DNA probes from each of the putative ancestral species on the same white clover cells, showed that half of the chromosomes hybridized with each probe. F1 hybrids were generated by embryo rescue and these showed strong interspecific chromosome pairing and produced a significant frequency of unreduced gametes, indicating the likely mode of polyploidization. The F1 hybrids are inter-fertile with white clover and function as synthetic white clovers, a valuable new resource for the re-incorporation of ancestral genomes into modern white clover for future plant breeding. CONCLUSIONS: Evidence from DNA sequence analyses, molecular cytogenetics, interspecific hybridization and breeding experiments supports the hypothesis that a diploid alpine species (T. pallescens) hybridized with a diploid coastal species (T. occidentale) to generate tetraploid T. repens. The coming together of these two narrowly adapted species (one alpine and the other maritime), along with allotetraploidy, has led to a transgressive hybrid with a broad adaptive range.


Asunto(s)
Quimera/genética , Evolución Molecular , Genoma de Planta/genética , Trifolium/genética , Adaptación Biológica/genética , Secuencia de Bases , Cruzamiento , Quimera/clasificación , Emparejamiento Cromosómico , Cromosomas de las Plantas/genética , Análisis Citogenético , ADN de Cloroplastos/química , ADN de Cloroplastos/genética , ADN de Plantas/química , ADN de Plantas/genética , ADN Ribosómico/química , ADN Ribosómico/genética , ADN Espaciador Ribosómico/química , ADN Espaciador Ribosómico/genética , Diploidia , Genotipo , Hibridación Genética , Datos de Secuencia Molecular , Filogenia , Hojas de la Planta/genética , Polen/genética , Semillas/genética , Análisis de Secuencia de ADN , Tetraploidía , Trifolium/clasificación
8.
Phys Rev Lett ; 108(13): 133401, 2012 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-22540697

RESUMEN

Explosions of large Xe clusters ( ~ 11,000) irradiated by femtosecond pulses of 850 eV x-ray photons focused to an intensity of up to 10(17) W/cm(2) from the Linac Coherent Light Source were investigated experimentally. Measurements of ion charge-state distributions and energy spectra exhibit strong evidence for the formation of a Xe nanoplasma in the intense x-ray pulse. This x-ray produced Xe nanoplasma is accompanied by a three-body recombination and hydrodynamic expansion. These experimental results appear to be consistent with a model in which a spherically exploding nanoplasma is formed inside the Xe cluster and where the plasma temperature is determined by photoionization heating.

9.
Heredity (Edinb) ; 108(3): 219-28, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21792224

RESUMEN

Analyzing the processes that determine whether species boundaries are maintained on secondary contact may shed light on the early phase of speciation. In Anacamptis morio and Anacamptis longicornu, two Mediterranean orchid sister-species, we used molecular and morphological analyses, together with estimates of pollination success and experimental crosses, to assess whether floral isolation can shelter the species' genomes from genetic admixture on secondary contact. We found substantial genetic and morphological homogenization in sympatric populations in combination with an apparent lack of postmating isolation. We further detected asymmetric introgression in the sympatric populations and an imbalance in cytotype representation, which may be due either to a difference in flowering phenology or else be a consequence of cytonuclear incompatibilities. Estimates of genetic clines for markers across sympatric zones revealed markers that significantly deviated from neutral expectations. We observed a significant correlation between spur length and reproductive success in sympatric populations, which may suggest that directional selection is the main cause of morphological differentiation in this species pair. Our results suggest that allopatric divergence has not led to the evolution of sufficient reproductive isolation to prevent genomic admixture on secondary contact in this orchid species pair.


Asunto(s)
Flores/genética , Orchidaceae/genética , Polinización , Análisis del Polimorfismo de Longitud de Fragmentos Amplificados , Evolución Biológica , Cruzamientos Genéticos , Genotipo , Hibridación Genética , Fenotipo , Sitios de Carácter Cuantitativo , Reproducción
10.
J Phys Chem A ; 116(36): 9058-70, 2012 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-22916845

RESUMEN

Structures, heats of formation, ionization energies, and proton affinities of selenium, argon dimer, argon-chlorine, and their hydrides (Se, SeH, SeH2, ArH, ArH2, Ar2, Ar2H, Ar2H2, ArCl, and ArHCl) are estimated by quantum chemistry calculations using G3, G4, and W1 composite methods and coupled cluster approach at the CCSD(T)/aug-cc-pVTZ levels. Thermochemistry of the reactions between ions A(+) = Se(•+), SeH(+), SeH2(•+), SeH3(+), Ar2(•+), Ar2H(+), Ar2H2(•+), Ar2H3(+), ArCl(+), ArClH(•+), and ArClH2(+) with various neutral gas G commonly used in dynamic reaction chamber-inductively coupled plasma-mass spectrometry (DRC-ICP-MS) (G = H2, CH4, NH3, O2, CO, CO2, NO, and N2O) has been investigated.

11.
Chemosphere ; 303(Pt 1): 134969, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35588881

RESUMEN

A systematic investigation on the isotopic and elemental signature, for both stable and radioactive elements, and mineral contents was performed to examine the characteristics of subsurface formations collected at different depths between 3.962 km and 4.115 km around deep-laying coal seams located under the Marmarica plateau in Egypt. Concentrations of major and minor oxides (Na2O, MgO, Al2O3, SiO2, SO3, K2O, CaO, TiO2, MnO, ΣFeO + Fe2O3, SrO, ZrO2, and BaO) were determined by X-ray fluorescence and dependencies among these concentrations revealed the type and sort of the formations. Organic contents were determined by Fourier Transform infrared spectroscopy to investigate the variation of the CO/CC bonding ratio with depth. Rare earth elements (REE), specifically Y, Sc, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu were determined by inductively coupled plasma mass spectrometry while actinoids were detected by the radioactive decay of its daughter nuclei. The results showed a high trapping of REE elements and actinoids in layers above the coal seams which indicates the occurrence of aqueous flow followed by possible sorption in these layers. The mobility of the fluid was investigated using the process radioactive decay series between Ra226 and Ac228 from one side and their daughters from the other side.


Asunto(s)
Carbón Mineral , Metales de Tierras Raras , Carbón Mineral/análisis , Isótopos/análisis , Metales de Tierras Raras/análisis , Minerales , Dióxido de Silicio
12.
Front Plant Sci ; 13: 858714, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35371143

RESUMEN

White clover (Trifolium repens) is an allotetraploid pasture legume widely used in moist temperate climates, but its vulnerability to drought, grazing pressure and pests has restricted its wider use. A related species, Caucasian clover (Trifolium ambiguum), is a potential source of resistances to drought, cold, grazing pressure and pests that could potentially be transferred to white clover by interspecific hybridization. Although direct hybridization has been achieved with difficulty, the hybrids have not been easy to backcross for introgression breeding and no interspecific chromosome recombination has been demonstrated. The present work shows that interspecific recombination can be achieved by using Trifolium occidentale, one of the ancestral parents of T. repens, as a bridging species and that large white clover breeding populations carrying recombinant chromosomes can be generated. A 4x hybrid between T. ambiguum and T. occidentale was crossed with T. repens and then backcrossed for two generations. Five backcross hybrid plants with phenotypes appearing to combine traits from the parent species were selected for FISH-GISH analyses. Recombinant chromosome segments from T. ambiguum were found in all five plants, suggesting that recombination frequencies were significant and sufficient for introgression breeding. Despite early chromosome imbalances, the backcross populations were fertile and produced large numbers of seeds. These hybrids represent a major new resource for the breeding of novel resilient forms of white clover.

13.
Ann Bot ; 108(7): 1269-77, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21880661

RESUMEN

BACKGROUND AND AIMS: DNA sequence similarities and hybridization patterns in Trifolium (clovers) section Trifoliastrum suggest that rapid radiation from a common ancestral source led to this complex of diverse species distributed across Europe, western Asia and North Africa. Two of the most geographically and ecologically divergent of these species are the rhizomatous T. ambiguum from high altitudes in eastern Europe and western Asia and the stoloniferous T. occidentale from sea level in western Europe. Attempts were made to hybridize these species to ascertain whether, despite this separation, gene flow could be achieved, indicating the retention of the genetic factors necessary for hybridization. METHODS: Three F(1) hybrids formed after embryo rescue were described, characterized by conventional and molecular cytogenetics, subjected to fertility tests and progeny generations were developed. RESULTS AND CONCLUSIONS: Partially fertile hybrids between Trifolium ambiguum and T. occidentale were obtained for the first time. The F(1) hybrids produced seeds after open-pollination, and also produced triploid progeny in backcrosses to T. occidentale from the functioning of unreduced gametes in the hybrids. These plants were fertile and produced progeny with T. occidentale and with T. repens. Meiotic chromosome pairing in the F(1) showed six to eight bivalents per pollen mother cell, indicating pairing between the parental genomes. A chromosome-doubled form of one hybrid, produced using colchicine, showed some multivalents, indicative of interspecific chromosome pairing. The hybrid plants were robust and combined phenotypic characteristics of both species, having stolons, thick roots and a few rhizomes. Results show that despite separation by the entire breadth of Europe, the speciation process is incomplete, and these taxa have partially retained most of the genetic compatibilities needed for hybridization (possibly except for endosperm development, which was not tested). The fertile progeny populations could lead to new clover breeding strategies based on new hybrid forms.


Asunto(s)
Quimera/genética , Diploidia , Trifolium/genética , Emparejamiento Cromosómico , Europa (Continente) , Flujo Génico , Transferencia de Gen Horizontal , Especiación Genética , Genoma de Planta , Hibridación Genética , Triploidía
14.
Fungal Genet Biol ; 45(2): 84-93, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17919950

RESUMEN

A fundamental hallmark of fungal growth is that vegetative hyphae grow exclusively by extension at the hyphal tip. However, this model of apical growth is incompatible with endophyte colonization of grasses by the symbiotic Neotyphodium and Epichloë species. These fungi are transmitted through host seed, and colonize aerial tissues that develop from infected shoot apical meristems of the seedling and tillers. We present evidence that vegetative hyphae of Neotyphodium and Epichloë species infect grass leaves via a novel mechanism of growth, intercalary division and extension. Hyphae are attached to enlarging host cells, and cumulative growth along the length of the filament enables the fungus to extend at the same rate as the host. This is the first evidence of intercalary growth in fungi and directly challenges the centuries-old model that fungi grow exclusively at hyphal tips. A new model describing the colonization of grasses by clavicipitaceous endophytes is described.


Asunto(s)
Ascomicetos/crecimiento & desarrollo , Lolium/microbiología , Ascomicetos/ultraestructura , Hifa/crecimiento & desarrollo , Hifa/ultraestructura , Lolium/fisiología , Microscopía Confocal , Hojas de la Planta/microbiología , Simbiosis
15.
Microbiol Res ; 163(4): 445-55, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-17223327

RESUMEN

The chemical composition of the Tamarix boveana volatile oils obtained from the whole aerial part, flowers, leaves and stems by steam distillation was analysed using gas chromatograph (GC)-flame ionization detectors (FID) and GC-MS. Sixty-two components were identified. Hexadecanoic acid (18.14%), docosane (13.34%), germacrene D (7.68%), fenchyl acetate (7.34%), Benzyl benzoate (4.11%) were found to be the major components in the whole aerial parts. This composition differed according to the tested part: 2.4 Nonadienal was the main compound in the flowers (12.13%) while germacrene D was the major component in leaves (31.43%) and hexadecanoic acid in the stems (13.94%). To evaluate in vitro antimicrobial activity, all volatile oils were tested against six Gram-positive and Gram-negative bacteria and four fungi. The T. boveana volatile oils exhibited an interesting antibacterial activity against all strains tested except Pseudomonas aeruginosa but no antifungal activity was detected.


Asunto(s)
Antiinfecciosos/química , Antiinfecciosos/farmacología , Aceites Volátiles/química , Aceites Volátiles/farmacología , Extractos Vegetales/química , Extractos Vegetales/farmacología , Tamaricaceae/química , Antiinfecciosos/aislamiento & purificación , Flores/química , Hongos/efectos de los fármacos , Hongos/crecimiento & desarrollo , Cromatografía de Gases y Espectrometría de Masas , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Gramnegativas/crecimiento & desarrollo , Bacterias Grampositivas/efectos de los fármacos , Bacterias Grampositivas/crecimiento & desarrollo , Pruebas de Sensibilidad Microbiana , Aceites Volátiles/aislamiento & purificación , Extractos Vegetales/aislamiento & purificación , Hojas de la Planta/química , Tallos de la Planta/química
16.
Microbiol Res ; 163(1): 87-95, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-17482441

RESUMEN

The chemical composition of the volatile fractions obtained by steam distillation from the capitula (C) and the aerial parts of Rhaponticum acaule DC were analysed by GC-MS. From the 57 identified constituents, representing 95.5% and 96.3% of the two oils, respectively, methyl eugenol, epi-13 manool, beta-ionone, beta-bisabolol, 1-octadecanol, phytol and farnesyl acetate were found to be the main components. Furthermore, the oils were tested against six Gram-positive and Gram-negative bacteria and four phytopathogenic fungi. It was found that oils from both parts of R. acaule, and especially that of C, exhibited interesting antibacterial activity, but no antifungal activity was observed.


Asunto(s)
Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Leuzea/química , Aceites Volátiles/farmacología , Componentes Aéreos de las Plantas/química , Aceites de Plantas/farmacología , Pruebas de Sensibilidad Microbiana , Aceites Volátiles/aislamiento & purificación , Aceites de Plantas/aislamiento & purificación , Plantas Medicinales/química , Túnez , Volatilización
17.
Nutr Health ; 19(3): 221-6, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-19009744

RESUMEN

Selected fish oils are the main industrial sources of PUFAs. However, this oil may be insufficient in the future to meet the expected growth in world demand for n-3 fatty acids (Tacon, 1995). Refined oils produced by marine microalgae represent potential sources of supplemental dietary fatty acids. This study examines the lipid and fatty acid composition of three microalgae that were isolated from the costal waters of Tunisia with particular interest on the variability of composition related to the cellular growth stage.


Asunto(s)
Eucariontes/crecimiento & desarrollo , Eucariontes/metabolismo , Ácidos Grasos Insaturados/análisis , Alimentos Orgánicos , Animales , Eucariontes/química , Ácidos Grasos/análisis , Humanos , Especificidad de la Especie
18.
Breast ; 31: 1-8, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27771499

RESUMEN

OBJECTIVE: The aim is to identify the epidemiological and clinicopathological features associated with young breast cancer (BC) patients and to discuss factors affecting tumor recurrence and DFS. PATIENTS & METHODS: A retrospective analysis was conducted based on medical records from young females patients aged ≤35 years with pathologically confirmed primary breast cancer treated during 2008-2010 at NCI. Cases with non invasive cancer and non carcinoma histology are excluded. RESULTS: Of the 5408 cases diagnosed with breast cancer, 554 were young. Four hundred & fifty eight patients representing 9.2% were within our inclusion criteria. Almost half of the patients (45.9%) presented with stage III. Axillary nodes involvement was in 63.9%, 83.3% were grade 2. More than one quarter of tumors was hormone receptors negative (28.8%) & Her2 was over-expressed in 30%. Mastectomy was offered in 72% while conservative breast surgery in 26%, 69.2% received chemotherapy either adjuvant, neoadjuvant or both, 82.5% received adjuvant radiotherapy, 68.6% received hormonal therapy. Metastatic disease developed in 51.3%, with 31% having more than one site of metastases. After a median follow up period of 66 months, the median DFS of patients was 60 months. The median DFS was significantly shorter among patients with positive lymph nodes (P < 0.0001), ER negative disease (P = 0.045) and stage III disease (P < 0.0001). CONCLUSION: Breast cancer in young women is aggressive from the time of diagnosis. Our results provide baseline data of young BC in the Middle East & North Africa region; thus, contributing to future epidemiological and hospital-based researches.


Asunto(s)
Factores de Edad , Neoplasias de la Mama/epidemiología , Adulto , Axila , Neoplasias de la Mama/química , Neoplasias de la Mama/patología , Supervivencia sin Enfermedad , Egipto/epidemiología , Femenino , Humanos , Estimación de Kaplan-Meier , Ganglios Linfáticos/patología , Mastectomía/estadística & datos numéricos , Estadificación de Neoplasias , Receptor ErbB-2/análisis , Estudios Retrospectivos , Adulto Joven
19.
Vaccine ; 35(28): 3523-3527, 2017 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-28533052

RESUMEN

Transmission of viruses from the commercial poultry to wild birds is an emerging paradigm of livestock-wildlife interface. Here, we report the identification and isolation of vaccine strains of avian paramyxovirus serotype 1 (APMV1) and avian coronaviruses (ACoV) from different wild bird species across eight Egyptian governorates between January 2014 and December 2015. Surveillance of avian respiratory viruses in free-ranging wild birds (n=297) identified three species that harboured or excreted APMV1 and ACoVs. Genetic characterization and phylogenetic analysis of recovered viruses revealed a close association with the most widely utilized vaccine strains in the country. These results highlight the potential spillover of vaccine-viruses probably due to extensive use of live-attenuated vaccines in the commercial poultry, and close interaction between domesticated and wild bird populations. Further exploring the full spectrum of vaccine-derived viral vaccine strains in wild birds might help to assess the emergence of future wild-birds origin viruses.


Asunto(s)
Aves/virología , Gammacoronavirus/aislamiento & purificación , Virus de la Enfermedad de Newcastle/aislamiento & purificación , Enfermedades de las Aves de Corral/prevención & control , Vacunas Virales , Animales , Animales Salvajes/virología , Egipto , Gammacoronavirus/genética , Gammacoronavirus/inmunología , Virus de la Enfermedad de Newcastle/genética , Virus de la Enfermedad de Newcastle/inmunología , Filogenia , Aves de Corral/virología , Enfermedades de las Aves de Corral/transmisión , Enfermedades de las Aves de Corral/virología , Vacunas Atenuadas/administración & dosificación
20.
Hum Immunol ; 67(1-2): 13-21, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16698420

RESUMEN

Interleukin-8 (IL-8), a potent chemoattractant, has been demonstrated to contribute to human cancer progression through its potential functions as a mitogenic, angiogenic, and motogenic factor. We designed a broad study to investigate whether genetic variation in IL-8 has implications for susceptibility to and prognosis in breast carcinoma. We used the allele-specific polymerase chain reaction to characterize the variation of the IL-8 promoter region for 308 unrelated Tunisian patients with breast carcinoma and 236 healthy control subjects. Associations of the clinicopathologic parameters and the genetic marker with the rates of the breast carcinoma-specific overall survival and the disease-free survival were assessed using univariate and multivariate analyses. A significantly increased risk of breast carcinoma was associated with heterozygous IL-8 (-251) TA (OR=1.58, p=0.02) and homozygous IL-8 (-251) AA (OR=1.76, p=0.01) variants. A significant association between the IL-8 (-251) AA homozygous genotype and the aggressive phenotype of breast carcinoma as defined by the high histological grade, auxiliary's lymph node metastasis, and large tumor size was found. The IL-8 (-251) A allele manifested a significant association with decreased overall survival and disease-free survival for breast carcinoma patients. The polymorphism in the promoter region of the IL-8 gene may not only represent a marker for the increased risk of breast carcinoma but also predict the clinical outcome.


Asunto(s)
Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/genética , Carcinoma/diagnóstico , Carcinoma/genética , Interleucina-8/genética , Polimorfismo Genético , Adulto , Neoplasias de la Mama/epidemiología , Carcinoma/epidemiología , Femenino , Variación Genética , Humanos , Persona de Mediana Edad , Epidemiología Molecular , Pronóstico , Regiones Promotoras Genéticas/genética , Riesgo , Túnez/epidemiología
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