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1.
Arch Virol ; 168(2): 44, 2023 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-36609878

RESUMO

The rise of antibiotic resistance in bacterial strains has led to vigorous exploration for alternative treatments. To this end, phage therapy has been revisited, and it is gaining increasing attention, as it may represent an efficient alternative for treating multiresistant pathogenic bacteria. Phage therapy is considered safe, and phages do not infect eukaryotic cells. There have been many studies investigating phage-host bacteria interactions and the ability of phages to target specific hosts. Escherichia coli is the causative agent of a multitude of infections, ranging from urinary tract infections to sepsis, with growing antibiotic resistance. In this study, we characterized the Escherichia phage fBC-Eco01, which was isolated from a water sample collected at Oued, Tunis. Electron microscopy showed that fBC-Eco01 phage particles have siphovirus morphology, with an icosahedral head of 61 ± 3 nm in diameter and a non-contractile tail of 94 ± 2 nm in length and 12 ± 0.9 nm in width. The genome of fBC-Eco01 is a linear double-stranded DNA of 43.466 bp with a GC content of 50.4%. Comparison to databases allowed annotation of the functions to 39 of the 78 predicted gene products. A single-step growth curve revealed that fBC-Eco01 has a latent period of 30 minutes and a burst size of 175 plaque-forming units (PFU) per infected cell. Genomic analysis indicated that fBC-Eco01 is a member of the subfamily Guernseyvirinae. It is most closely related to a group of phages of the genus Kagunavirus that infect Enterobacter, Raoultella, and Escherichia strains.


Assuntos
Bacteriófagos , Siphoviridae , Águas Residuárias , Tunísia , Genoma Viral , Bacteriófagos/genética , Escherichia coli/genética , Siphoviridae/genética
2.
Holist Nurs Pract ; 37(1): 34-44, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36378090

RESUMO

Given the serious threats posed by the COVID-19 virus, preventive measures and coping strategies are critical in lowering infection rates, managing disease transmission, and improving people's psychological well-being. This study aimed to evaluate the effect of telehealth nursing intervention on psychological status and coping strategies among parents during the second wave of COVID-19. A quasi-experimental (one group pre-/posttest) design was used. A purposive sample of 209 parents in Menoufia governorate, Egypt, was collected using Google Form. Tools: (1) Structured questionnaire for parents (a) Demographic data (b) Parents' knowledge regarding COVID-19. (2) Parents' preventive practices of the COVID-19 questionnaire. (3) Parents" coping strategies with COVID-19 pandemic questionnaire. (4) Depression, Anxiety, and Stress Scale (Arabic DASS-21). Approximately 82.8% of the participants had normal to mild depression after the telehealth nursing intervention compared with 62.6% before the telehealth nursing intervention. Approximately 55.4% of them had moderate to extremely severe level of anxiety before the telehealth nursing intervention compared with (21.6%) after the telehealth nursing intervention. Approximately 85.2% reported a normal level of stress after the telehealth nursing intervention compared with (62.7%) before the telehealth nursing. Telehealth nursing intervention was effective for improving parents' knowledge, preventive practice, and coping strategies during the second wave of COVID-19.


Assuntos
COVID-19 , Telemedicina , Humanos , Pandemias , Adaptação Psicológica , Ansiedade/psicologia , Pais , Estresse Psicológico/psicologia
3.
Arch Virol ; 167(5): 1333-1341, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35399144

RESUMO

Characterization of bacteriophages facilitates better understanding of their biology, host specificity, genomic diversity, and adaptation to their bacterial hosts. This, in turn, is important for the exploitation of phages for therapeutic purposes, as the use of uncharacterized phages may lead to treatment failure. The present study describes the isolation and characterization of a bacteriophage effective against the important clinical pathogen Escherichia coli, which shows increasing accumulation of antibiotic resistance. Phage fEg-Eco19, which is specific for a clinical E. coli strain, was isolated from an Egyptian sewage sample. Phage fEg-Eco19 formed clear, sharp-edged, round plaques. Electron microscopy showed that the isolated phage is tailed and therefore belongs to the order Caudovirales, and morphologically, it resembles siphoviruses. The diameter of the icosahedral head of fEg-Eco19 is 68 ± 2 nm, and the non-contractile tail length and diameter are 118 ± 0.2 and 13 ± 0.6 nm, respectively. The host range of the phage was found to be narrow, as it infected only two out of 137 clinical E. coli strains tested. The phage genome is 45,805 bp in length with a GC content of 50.3% and contains 76 predicted genes. Comparison of predicted and experimental restriction digestion patterns allowed rough mapping of the physical ends of the phage genome, which was confirmed using the PhageTerm tool. Annotation of the predicted genes revealed gene products belonging to several functional groups, including regulatory proteins, DNA packaging and phage structural proteins, host lysis proteins, and proteins involved in DNA/RNA metabolism and replication.


Assuntos
Bacteriófagos , Caudovirales , Antibacterianos/farmacologia , Bacteriófagos/genética , Caudovirales/genética , Escherichia coli/genética , Genoma Viral , Especificidade de Hospedeiro
4.
Saudi J Biol Sci ; 29(3): 1611-1617, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35280572

RESUMO

Water stress is a critical abiotic stress for plant reduction in arid and semiarid zones and, has been discovered to be detrimental to the development of seedlings as well as the growth and physiological characteristics of many crops such as cotton. The objectives of our study were to determine the combining ability and genetic components for five quantitative traits [(leaf area (LA), leaf dry weight (LDW), plant height (PH), fiber length (2.5 percent SL), and lint cotton yield/plant (LCY/P)] under water shortage stress, a half diallel cross between six cotton genotypes representing a wide range of cotton characteristics was evaluated in RCBD with four replications. The genotype mean squares were significant for all traits studied, demonstrating significant variation among genotypes for all characters under water shortage stress. LCY/P had the highest phenotypic and genotypic correlation co-efficient with PH, LDW, and LA shortage. The highest direct effect on lint cotton yield was exhibited by leaf area (3.905), and the highest indirect effects of all traits were through LA, with the exception of 2.5 percent SL, which was through LDW. The highest dissimilarity (Euclidean Distance) between parental genotypes was between G.87 and G.94, followed by G.87 and Menoufi. G.94 was also a well-adapted genotype, and the combinations G.87 x G.94 and G.87 x Menoufi may outperform their parents. The combining ability analysis revealed highly significant differences between parental GCA effects and F1 crosses SCA effects. The variation of GCA and SCA demonstrated the assurance of additive and non- additive gene action in the inheritance of all traits studied. In terms of general combining ability (GCA) effects, parental genotype G.94 demonstrated the highest significant and positive GCA effects for all traits studied, with the exception of 2.5 percent SL, where G.87 revealed the highest significant and positive GCA effects. The effects of specific combining ability (SCA) revealed that the cross (G.87 x2G.94) revealed stable, positive, and significant SCA for all of the studied traits.

5.
Plants (Basel) ; 10(8)2021 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-34451704

RESUMO

Rice production under salinity stress is a critical challenge facing many countries, particularly those in arid and semi-arid regions. This challenge could be handled by applying novel approaches to overcome yield limiting factors and improve resource use efficiency. The usage of nanoparticles (NPs) could be a beneficial approach to managing the growing problem of soil salinity. The aim of our study was to investigate the advantageous effects of soaking and foliar application of silicon (Si) and selenium (Se), (NPs-Si at 12.5 mg L-1 and NPs-Se at 6.25 mg L-1) on root characteristics, moropho-physiological traits, and yields of two rice varieties (i.e., Giza 177 as a salt sensitive and Giza 178 as a salt tolerant) grown in saline soil compared to untreated plants (control treatment). Results showed that soaking NPs-Se resulted in the highest value of root thickness for Giza 178 (0.90 mm, 0.95 mm) and root volume (153.30 cm3, 154.30 cm3), while Giza 177 recorded 0.83 mm, 0.81 mm for root thickness and 143.30 cm3, 141.30 cm3 for root volume in the 2018 and 2019 seasons, respectively. Soaking NPs-Se, NPs-Si and foliar application of NPs-Se at BT resulted in the highest relative water content and dry matter, while foliar application of NPs-Si at BT gave the highest leaf area index of rice plants compared to the other treatments. Giza 178 (i.e., salt tolerant variety) significantly surpassed Giza 177 (i.e., salt sensitive variety) in the main yield components such as panicle number and filled grains/ panicle, while Giza 177 significantly exceeded Giza 178 in the panicle weight, 1000-grain weight, and unfilled grains number/ panicle. Soaking NPs-Se and foliar application of NPs-Si at BT resulted in the highest grain yield of 5.41 and 5.34 t ha-1 during 2018 and 5.00 and 4.91 t ha-1 during 2019, respectively. The salt sensitive variety (Giza 177) had the highest Na+ leaf content and Na+/K+ ratio as well as the lowest K+ leaf content during both seasons. Applying nano nutrients such as NPs-Si and NPs-Se improved the yield components of the salt sensitive variety (Giza 177) by enhancing its ion selectivity. Both NPs-Si and NPs-Se had almost the same mode of action to mitigate the harmful salinity and enhance plant growth, and subsequently improved the grain yield. In summary, the application of NPs-Si and NPs-Se is recommended as a result of their positive influence on rice growth and yield as well as minimizing the negative effects of salt stress.

6.
Plants (Basel) ; 9(10)2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-33053807

RESUMO

Given the expectancy of the water supply becoming scarce in the future and more expensive, water conservation during wheat production processes has become very crucial especially in saline sodic soil. Biochar and salicylic acid (SA) were used to assess the potential to alleviate the influences of depletion of available soil moisture (DAM) on physicochemical, physiological, biochemical attributes, as well as wheat production absorption (Triticum aestivum L. cv. Misr 1) and macro-elements. Two seasons (2018/2019 and 2019/2020) of field trials were investigated using twelve combinations of three water treatments (50%, 70%, and 90% DAM) and foliar- and soil-applied treatments (control, biochar, salicylic acid, and biochar + SA). Biochar treated plots amplified soil physicochemical attributes, leading to improved physiological traits and antioxidant enzymes, as well as yield related traits under water limitation conditions in both years. Similarly, synergistic use of biochar and salicylic acid greatly augmented the designed characteristics such as chlorophyll a, b, K+ content, relative water content (RWC), stomatal conductance, photosynthetic rate, and intrinsic water use efficiency, whilst exhibited inhibitory effects on proline content, electrolyte leakage, Na+ content SOD, POX, CAT, and MDA, consequently increased 1000-grain weight, number of grains spike-1, grain yield, as well nutrient uptake (N, P, K) under water limitation condition in both years, followed by treatment of sole biochar or SA compared to unamended plots treatment (control). Wheat productivity achieved further increasing at 70% DAM alongside synergistic use of biochar and SA which was on par with 50% DAM under unamended plots (control). It is concluded from the findings that coupled application of biochar alongside salicylic acid accomplished an efficient approach to mitigate the injurious influences of water limitation, along with further improvement of the soil, physiology, biochemical attributes, and wheat yield, as well nutrient uptake, under saline sodic soil.

7.
Viruses ; 12(6)2020 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-32486497

RESUMO

Acinetobacter baumannii is an opportunistic pathogen that presents a serious clinical challenge due to its increasing resistance to all available antibiotics. Phage therapy has been introduced recently to treat antibiotic-incurable A. baumannii infections. In search for new A. baumannii specific bacteriophages, 20 clinical A. baumannii strains were used in two pools in an attempt to enrich phages from sewage. The enrichment resulted in induction of resident prophage(s) and three temperate bacteriophages, named vB_AbaS_fEg-Aba01, vB_AbaS_fLi-Aba02 and vB_AbaS_fLi-Aba03, all able to infect only one strain (#6597) of the 20 clinical strains, were isolated. Morphological characteristics obtained by transmission electron microscopy together with the genomic information revealed that the phages belong to the family Siphoviridae. The ca. 35 kb genomic sequences of the phages were >99% identical to each other. The linear ds DNA genomes of the phages contained 10 nt cohesive end termini, 52-54 predicted genes, an attP site and one tRNA gene each. A database search revealed an >99% identical prophage in the genome of A.baumannii strain AbPK1 (acc. no. CP024576.1). Over 99% identical prophages were also identified from two of the original 20 clinical strains (#5707 and #5920) and both were shown to be spontaneously inducible, thus very likely being the origins of the isolated phages. The phage vB_AbaS_fEg-Aba01 was also able to lysogenize the susceptible strain #6597 demonstrating that it was fully functional. The phages showed a very narrow host range infecting only two A.baumannii strains. In conclusion, we have isolated and characterized three novel temperate Siphoviridae phages that infect A.baumannii.


Assuntos
Acinetobacter baumannii/virologia , Siphoviridae/fisiologia , DNA Viral/genética , DNA Viral/isolamento & purificação , Genoma Viral/genética , Lisogenia , Microscopia Eletrônica de Transmissão , Filogenia , Análise de Sequência de DNA , Siphoviridae/genética , Siphoviridae/isolamento & purificação , Siphoviridae/patogenicidade , Ensaio de Placa Viral , Ativação Viral
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