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1.
Chembiochem ; 24(22): e202300542, 2023 11 16.
Artículo en Inglés | MEDLINE | ID: mdl-37743259

RESUMEN

The current study compares the antibacterial activity of zinc oxide nanostructures (neZnO). For this purpose, two bacterial strains, Escherichia coli (ATCC 4157) and Staphylococcus aureus (ATCC 29213) were challenged in room light conditions with the aforementioned materials. Colloidal and hydrothermal methods were used to obtain the quasi-round and quasi-diamond platelet-shape nanostructures. Thus, the oxygen vacancy (VO ) effects on the surface of neZnO are also considered to assess its effects on antibacterial activity. The neZnO characterization was achieved by X-ray diffraction (XRD), a selected area electron diffraction (SAED) and Raman spectroscopy. The microstructural effects were monitored by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Furthermore, optical absorption ultraviolet visible spectrophotometry (UV-Vis) and X-ray photoelectron spectroscopy (XPS) analyses complement the physical characterization of these nanostructures; neZnO caused 50 % inhibition (IC50 ) at concentrations from 0.064 to 0.072 mg/mL for S. aureus and from 0.083 to 0.104 mg/mL for E. coli, indicating an increase in activity against S. aureus compared to E. coli. Consequently, quasi-diamond platelet-shaped nanostructures (average particle size of 377.6±10 nm) showed enhanced antibacterial activity compared to quasi-round agglomerated particles (average size of 442.8±12 nm), regardless of Vo presence or absence.


Asunto(s)
Nanopartículas del Metal , Nanoestructuras , Óxido de Zinc , Óxido de Zinc/farmacología , Óxido de Zinc/química , Escherichia coli , Staphylococcus aureus , Espectroscopía Infrarroja por Transformada de Fourier , Pruebas de Sensibilidad Microbiana , Antibacterianos/farmacología , Antibacterianos/química , Nanoestructuras/química , Difracción de Rayos X , Nanopartículas del Metal/química
2.
J Invertebr Pathol ; 186: 107686, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34780719

RESUMEN

Melissococcus plutonius is a pathogenic bacterium that affects honeybee brood triggering colony collapse in severe cases. The bacterium causes a European foulbrood (EFB) disease in the honeybee populations, impacting beekeeping and agricultural industries. The pathogenesis, epidemiology, and variants of M. plutonius have been studied, but the virulence factors involved in larval infection are still unknown. Recently, an in-silico study suggested putative genes that might play a role in the pathogenesis of EFB. However, studies are required to determine their function as virulence factors. In addition, the few studies of clonal complexes (CCs), virulence factors, and variation in the honeybee larvae mortality have interfered with the development of more efficient control methods. The research, development, and differences in virulence between genetic variants (CCs) of M. plutonius and potential virulence factors implicated in honeybee larval mortality are discussed in this review.


Asunto(s)
Abejas/microbiología , Enterococcaceae/fisiología , Enterococcaceae/patogenicidad , Animales , Apicultura , Abejas/crecimiento & desarrollo , Larva/crecimiento & desarrollo , Larva/microbiología , Virulencia , Factores de Virulencia/genética
3.
J Invertebr Pathol ; 159: 71-77, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30312627

RESUMEN

European foulbrood (EFB) caused by Melissococcus plutonius is an important bee brood disease but, in Mexico, information about this bacterium is limited. We evaluated the prevalence of typical and atypical strains in beehives of seven apicultural regions of the state of Chihuahua, Mexico. We performed MLST and phylogenetic analysis to characterize the isolates. Prevalence was highest 59%, in the region of Chihuahua, and lowest, 14%, in the regions of Cuauhtémoc and Nuevo Casas Grandes. Typical and atypical strains were identified in hives from all regions; however, in the regions of Parral, Cuauhtémoc and Aldama, the atypical strains were only detected in combination with typical strains. We obtained 81 isolates of M. plutonius and identified seven sequence types, of which three were new types. Additionally, we observed a relation between sequence type and the region where the strain was isolated. Phylogenetic analysis and multilocus sequence typing using goeBURST analysis showed that 97.5% of the isolates correspond to the Clonal Complex (CC) 12 and 2.5% to the CC3. Our work is the first molecular characterization of M. plutonius in Mexico and contributes to global information about the epidemiology of this pathogen.


Asunto(s)
Abejas/microbiología , Enterococcaceae/fisiología , Filogenia , Animales , Larva/microbiología , México , Prevalencia
4.
Hum Mutat ; 37(12): 1263-1271, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27604516

RESUMEN

As whole genome sequencing becomes cheaper and faster, it will progressively substitute targeted next-generation sequencing as standard practice in research and diagnostics. However, computing cost-performance ratio is not advancing at an equivalent rate. Therefore, it is essential to evaluate the robustness of the variant detection process taking into account the computing resources required. We have benchmarked six combinations of state-of-the-art read aligners (BWA-MEM and GEM3) and variant callers (FreeBayes, GATK HaplotypeCaller, SAMtools) on whole genome and whole exome sequencing data from the NA12878 human sample. Results have been compared between them and against the NIST Genome in a Bottle (GIAB) variants reference dataset. We report differences in speed of up to 20 times in some steps of the process and have observed that SNV, and to a lesser extent InDel, detection is highly consistent in 70% of the genome. SNV, and especially InDel, detection is less reliable in 20% of the genome, and almost unfeasible in the remaining 10%. These findings will aid in choosing the appropriate tools bearing in mind objectives, workload, and computing infrastructure available.


Asunto(s)
Biología Computacional/métodos , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Análisis de Secuencia de ADN/métodos , Exoma , Variación Genética , Genoma Humano , Humanos , Programas Informáticos
6.
Front Immunol ; 13: 932559, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36172370

RESUMEN

Chimeric antigen receptor (CAR)-based therapies are presented as innovative treatments for multiple malignancies. Despite their clinical success, there is scientific evidence of the limitations of these therapies mainly due to immunogenicity issues, toxicities associated with the infusion of the product, and relapses of the tumor. As a result, novel approaches are appearing aiming to solve and/or mitigate the harmful effects of CAR-T therapies. These include strategies based on the use of ligands as binding moieties or ligand-based CAR-T cells. Several proposals are currently under development, with some undergoing clinical trials to assess their potential benefits. In addition to these, therapies such as chimeric autoantibody receptor (CAAR), B-cell receptor antigen for reverse targeting (BAR), and even chimeric human leukocyte antigen (HLA) antibody receptor (CHAR) have emerged, benefiting from the advantages of antigenic ligands as antibody-binding motifs. This review focuses on the potential role that ligands can play in current and future antitumor treatments and in other types of diseases, such as autoimmune diseases or problems associated with transplantation.


Asunto(s)
Neoplasias , Receptores Quiméricos de Antígenos , Humanos , Ligandos , Receptores de Antígenos de Linfocitos B/metabolismo , Receptores de Antígenos de Linfocitos T , Linfocitos T
7.
Artículo en Inglés | MEDLINE | ID: mdl-26451818

RESUMEN

The recent advent of high-throughput sequencing machines producing big amounts of short reads has boosted the interest in efficient string searching techniques. As of today, many mainstream sequence alignment software tools rely on a special data structure, called the FM-index, which allows for fast exact searches in large genomic references. However, such searches translate into a pseudo-random memory access pattern, thus making memory access the limiting factor of all computation-efficient implementations, both on CPUs and GPUs. Here, we show that several strategies can be put in place to remove the memory bottleneck on the GPU: more compact indexes can be implemented by having more threads work cooperatively on larger memory blocks, and a k-step FM-index can be used to further reduce the number of memory accesses. The combination of those and other optimisations yields an implementation that is able to process about two Gbases of queries per second on our test platform, being about 8 × faster than a comparable multi-core CPU version, and about 3 × to 5 × faster than the FM-index implementation on the GPU provided by the recently announced Nvidia NVBIO bioinformatics library.


Asunto(s)
Algoritmos , Gráficos por Computador/instrumentación , Equipos de Almacenamiento de Computador , Secuenciación de Nucleótidos de Alto Rendimiento/instrumentación , Almacenamiento y Recuperación de la Información/métodos , Procesamiento de Señales Asistido por Computador/instrumentación , Diseño de Equipo , Análisis de Falla de Equipo
8.
Rev Alerg Mex ; 59(3): 148-54, 2012.
Artículo en Español | MEDLINE | ID: mdl-24007991

RESUMEN

BACKGROUND: Allergic diseases constitute a worldwide health problem and mites are among the main etiological agents. OBJECTIVE: To characterize the sensitization to the mites Dermatophagoides pteronyssinus, Dermatophagoides siboney, and Blomia tropicalis, by skin tests in a children allergic sample from Cuba. METHODS: This is a descriptive transversal investigation that included 103 allergic children, with ages ranging from 3 to 15 years, who underwent skin prick tests with D. pteronyssinus, D. siboney, and B. tropicalis allergenic extracts. For the analysis of the results, sex, place of residence and degree of exposure to house dust were considered. RESULTS: The greater sensitization was to D. pteronyssinus (36,9%), followed by D. siboney (35%) and B. tropicalis (33%). The greater geometric mean of the wheal diameter was 5,14 mm for D. pteronyssinus (IC95%: 4.52-5.76 mm); 4.82 mm for D. siboney (IC95%: 4.22-5.43 mm) and 4.25 mm for B. tropicalis (IC95%: 3.93-4.58 mm). Fifty six children (54.3%) were not sensitive to none of the three mites. In 45.7% we found sensitization at least to one mite, and 21.4% were sensitive to the three mites. There were no significant differences (p >0.05) in the sensitization according to sex, place of residence and degree of exposure to house dust. The percentage of sensitive patients with rhinitis plus asthma was more significant (p < 0.001), and in them, the geometric mean of the wheal diameter was significant for D. pteronyssinus (p=0.028) and D. siboney (p=0. 027). CONCLUSIONS: A third of our studied child population, residing in a non-industrialized tropical area, presented sensitization to one or some of the three tested mites. There was a different pattern of sensitization with mites in relation to gender. Patients with asthma plus rhinitis showed more sensitization concerning the number and intensity of the skin tests.


Asunto(s)
Dermatophagoides pteronyssinus , Pyroglyphidae , Alérgenos , Animales , Asma/epidemiología , Niño , Cuba , Dermatophagoides pteronyssinus/inmunología , Humanos , Pyroglyphidae/inmunología , Pruebas Cutáneas
9.
Rev Alerg Mex ; 52(1): 18-24, 2005.
Artículo en Español | MEDLINE | ID: mdl-15957469

RESUMEN

BACKGROUND: Information on asthma is fundamental for an adequate control and management of patients who suffer from it, or for their relatives; hence, new educational programs are being carried out in order to achieve this aim. OBJECTIVE: To identify learning requirements for its subsequent use in the development of an educational program. MATERIAL AND METHODS: A descriptive study was carried out. 326 surveys were applied to relatives of pediatric patients seen at the allergology department of Hospital Leonor Perez, from April to September 2003. Frequencies, percentages, as well as Pearson's chi-square test were used in order to compare groups. RESULTS: An inadequate knowledge of treatment was observed in 69.3% of the cases, of its physiopathology in 84.7%, of its preventive medication and of crisis in 51.7 and 59.5%, respectively, as well as from the importance of both treatments in 65.3% of them. Most of the relatives included in this study recognized the importance of being instructed in the disease process (94.8%). There were no significant differences between the group of relatives with prior specialized attention and the group who attended consultation for the first time; except for preventive medication to treat crisis, where the first one showed better knowledge of the disease (p = 0.002). Difference on the overall knowledge was also better in the first group, although lower than expected. CONCLUSIONS: It is important to apply an educational program aimed at improving levels of knowledge on specific aspects of asthma.


Asunto(s)
Asma , Salud de la Familia , Educación en Salud , Niño , Estudios Transversales , Humanos , Encuestas y Cuestionarios
10.
J. bras. urol ; 13(4): 103-4, jul.-ago. 1987. ilus
Artículo en Portugués | LILACS | ID: lil-47766

RESUMEN

Paciente com adenocarcinoma prostático apresentou-se com priapismo e metástase tumoral na glande. Foi tratado através de orquiectomia e evoluiu para o óbito


Asunto(s)
Anciano , Humanos , Masculino , Adenocarcinoma/secundario , Neoplasias de la Próstata , Neoplasias del Pene/secundario , Adenocarcinoma/patología
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