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1.
Pathogens ; 12(9)2023 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-37764943

RESUMEN

Arboviruses are an important group of pathogens that cause diseases of medical and veterinary concern worldwide. The interactions of these viruses with their host cells are complex, and frequently, the coexistence of two different viruses in the same cell results in the inhibition of replication in one of the viruses, which is a phenomenon called viral interference. This phenomenon can be exploited to develop antiviral strategies. Insect cell lines persistently infected with arboviruses are useful models with which to study viral interference. In this work, a model of C6/36-HT cells (from Aedes albopictus mosquitoes) persistently infected with Dengue virus, serotype 2, was used. Viral interference was evaluated via plaque and flow cytometry assays. The presence of heterotypic interference against the other serotypes of the same virus and homologous interference against yellow fever virus was determined; however, this cell line did not display heterologous viral interference against Sindbis virus. The mechanisms responsible for viral interference have not been fully elucidated, but small RNAs could be involved. However, the silencing of Ago3, a key protein in the genome-derived P-element-induced wimpy testis pathway, did not alter the viral interference process, suggesting that viral interference occurs independent of this pathway.

2.
Microbiol Res ; 264: 127158, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36027845

RESUMEN

The geothermal zone of Araró, México, is located within the trans-Mexican volcanic belt, an area with numerous arsenic (As)-rich hot springs. In this study, the draft genome sequence of two endemic Bacillus strains (ZAP17 and ZAP62) from Araró microbial mat hot springs was determined, which were able to grow on arsenate As(V) (up to 64 mM) and arsenite As(III) (up to 32 mM). Phylogenetic analysis based on 16 S rRNA and gyrB sequences, as well as genome sequence analysis based on average nucleotide identity (>96 %) and digital DNA-DNA hybridization (>70 %), indicated that these strains belong to the Bacillus paralicheniformis ZAP17 and Bacillus altitudinis ZAP62. Furthermore, through genome mining, it was identified two arsenic resistance operons, arsRBC, and arsRBCDA in both strains as potential determinants of As resistance. Predicted ArsA (arsenial pump-driving ATPase), ArsB (Arsenical efflux pump protein), ArsC (Arsenate reductase), ArsD (Arsenical efflux pump protein) and ArsR (Metalloregulator/ars operon repressor) proteins, clearly grouped with their respective clades corresponding to other characterized bacterial species, mainly Firmicutes. To further evaluate the functionality of the ars operons in ZAP17 and ZAP62 strains, our results showed that arsRBC and arsRBCDA genes were expressed in the presence of As(III). Finally, the presence of ars operons in the genome of Bacillus species residing in As-rich environments, such as the Araró hot springs, might be a potential mechanism to survive under such harsh conditions.


Asunto(s)
Arsénico , Arsenicales , Bacillus , Manantiales de Aguas Termales , Bacillus/genética , Bacillus/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , ADN , Operón , Filogenia
3.
Curr Res Microb Sci ; 2: 100028, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34841319

RESUMEN

The endophytic bacterial diversity of root, stem, and leaf tissues of Mexican husk tomato plants (Physalis ixocarpa) was compared and deciphered, and screened for their plant growth-promoting activity and antagonism against fungal phytopathogens. Total 315 isolates (108 roots, 102 stems, and 105 leaves) were obtained and characterized by 16S ribosomal gene sequencing. The most abundant genera were Bacillus, Microbacterium, Pseudomonas, and Stenotrophomonas. Unique species were found for each tissue analyzed, along with B. thuringiensis, B. toyonensis, Neobacillus drentensis, Paenibacillus castaneae, P. fluorescens, P. poae, and S. maltophilia present throughout the plant. Biodiversity indices did not show significant differences, but root tissues showed the highest abundance of bacterial endophytes. Several isolates showed excellent promotion activities in Physalis ixocarpa seedlings, increasing the length and weight of the root, total biomass, and chlorophyll content. Various isolates also exhibited antagonism against fungal pathogens. Among screened isolates, Neobacillus drentensis CH23 was found in all plant compartments, exhibiting growth-promoting activity and fungal antagonism. Strain CH23 and other endophytes showed the production of indoleacetic acid, siderophores, proteases, and solubilization of phosphates. These results demonstrate that the husk tomato plant endobiome has a high potential as a bioinoculating agent for agriculturally important crops.

4.
Int J Spine Surg ; 14(s4): S16-S20, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33900939

RESUMEN

BACKGROUND: Ankylosing spondylitis (AS) is associated with high rates of severe thoracolumbar fractures, in many cases with neurological deficits. It is currently a point of debate as to whether the optimal surgical treatment is posterior fixation and fusion or combined approaches. Vascular injuries in this kind of fracture are a challenging issue to solve in the management of these patients. METHODS: We are reporting the case of a 65-year-old man who presented an L4 traumatic fracture-dislocation. He had a long history of symptomatic AS. No neurological deficits were detected during the initial exploration. During the preoperative work-up, a lumbar spine computed tomography (CT) scan was taken with vascular reconstruction of the abdominal vessels. It confirmed the compression of the abdominal aorta, which had caused more than 90% stenosis. A posterior approach, an open reduction, and fixation with pedicle screws were performed, without hemodynamic or neurological changes. A postoperative angiography demonstrated a complete recovery of the vessel caliber, without contrast leaks. RESULTS: After a 2-year follow-up, the patient was pain free and the CT scan revealed bone fusion. CONCLUSIONS: The vascular structures involved in severe thoracolumbar fractures present a dangerous situation that should be considered in the choice of the surgical approach. The posterior approach alone may be a good option in the absence of vascular damage. However, due to risk of vessel rupture during the fracture reduction, vascular surgeons must take part in the surgery. LEVEL OF EVIDENCE: 5. CLINICAL RELEVANCE: The article provides help for surgeons who have to treat severe fractures in the context of ankylosing spondylitis.

5.
Neurocirugía (Soc. Luso-Esp. Neurocir.) ; 32(2): 89-93, mar.- apr. 2021. ilus
Artículo en Español | IBECS | ID: ibc-222447

RESUMEN

Los ganglioglioma son tumores bien diferenciados, de crecimiento lento, compuestos por una mezcla de células ganglionares maduras y gliales. La mayoría son de grado I de la OMS. Aparecen predominantemente en niños y adultos jóvenes. La mayoría se localizan a nivel del lóbulo temporal, y la sintomatología más frecuente son las crisis epilépticas de difícil control farmacológico. En general tienen buen pronóstico tras la resección quirúrgica. La variante anaplásica, considerada grado III de la OMS, presenta mayor agresividad clínica y radiológica. La diseminación leptomeníngea es excepcional en estos tipos de tumores, pero cuando es diagnosticada presenta un curso rápidamente progresivo y fatal para el paciente (AU)


Gangliogliomas are well-differentiated, slow-growing tumors. The majority are grade I of WHO. It appears predominantly in children and young adults. Most are located at the temporal lobe, and as symptomatology more frequent epileptic seizures of difficult pharmacological control. In general, they have a good prognosis after surgical resection. The anaplasic variant, considered to be grade III of the WHO, presents greater clinical and radiological aggressiveness. Leptomeningeal dissemination is exceptional in these types of tumors, but when diagnosed it presents a rapidly progressive and fatal course for the patient (AU)


Asunto(s)
Humanos , Femenino , Adulto , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/cirugía , Ganglioglioma/diagnóstico por imagen , Ganglioglioma/cirugía , Epilepsia/etiología , Imagen por Resonancia Magnética
6.
Neurocirugia (Astur : Engl Ed) ; 32(2): 89-93, 2021.
Artículo en Inglés, Español | MEDLINE | ID: mdl-32265155

RESUMEN

Gangliogliomas are well-differentiated, slow-growing tumors. The majority are gradeI of WHO. It appears predominantly in children and young adults. Most are located at the temporal lobe, and as symptomatology more frequent epileptic seizures of difficult pharmacological control. In general, they have a good prognosis after surgical resection. The anaplasic variant, considered to be gradeIII of the WHO, presents greater clinical and radiological aggressiveness. Leptomeningeal dissemination is exceptional in these types of tumors, but when diagnosed it presents a rapidly progressive and fatal course for the patient.


Asunto(s)
Neoplasias Encefálicas , Epilepsia , Ganglioglioma , Niño , Ganglioglioma/cirugía , Humanos , Imagen por Resonancia Magnética , Convulsiones , Lóbulo Temporal , Adulto Joven
7.
3 Biotech ; 10(5): 220, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32355594

RESUMEN

Here we report the draft genome sequence of bacterial strain CR71, consisting of a single chromosome with 5,914,775 base pairs (bp), 34.7% G + C content, and 5733 protein-coding genes. Phylogenetic analysis indicates that the CR71 strain is affiliated with Bacillus thuringiensis species, with an average nucleotide identity > 96% and genome to genome distance > 70%. The genome of B. thuringiensis strain CR71 contains genes potentially involved in a wide variety of both plant pathogen-antagonistic and plant-growth-promoting activities, such as biofilm production; acetoin, butanediol, and indoleacetic acid (IAA) synthesis; production of quorum-sensing molecules; synthesis of toxins and lytic enzymes; and promotion of tolerance to oxidative, metal, and salt stress. Additionally, antiSMASH analysis revealed a potential synthesis of siderophores and peptide antibiotics. To confirm the in silico data, strain CR71 was inoculated into cucumber plants (Cucumis sativus L.) in a field trial, in which we observed an increase in stem thickness, as well as shoot fresh weight and length. Importantly, compared to un-inoculated control plants, plants inoculated with strain CR71 increased the size/weight ratio of cucumber fruits (34.99%), biovolume index (16.8%), and total fruit yield (34.97%). In conclusion, genome analysis of strain CR71 confirmed multifactorial plant-beneficial mechanisms and the potential of CR71 as an agricultural bio-inoculant.

8.
Asian Spine J ; 13(1): 119-125, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30347527

RESUMEN

STUDY DESIGN: A retrospective study. PURPOSE: We report our experience with 5-aminolevulinic acid (5-ALA)-assisted resection of spinal cord ependymomas in adults. OVERVIEW OF LITERATURE: Ependymoma is the most frequent primary spinal cord tumor in adults. Surgery is the treatment of choice in most cases. However, while complete resection is achieved in approximately 80% of cases, clinical improvement is achieved in 15% only. Five-ALA fluorescence-guided surgery seems to be useful for this tumor type. METHODS: We studied 14 patients undergoing 5-ALA fluorescence-guided surgery for spinal cord ependymomas in our service. The modified McCormick classification was used to determine clinical status and the degree of resection was assessed with magnetic resonance imaging. RESULTS: Of the 14 patients, the tumor showed an intense emission of fluorescence in 12 and the fluorescence was weak and nonuniform in two. Complete resection was achieved in 11 cases. According to the McCormick classification, 10 patients improved, two remained the same, and two deteriorated. CONCLUSIONS: Our results confirm that 5-ALA fluorescence-guided resection is useful in spinal cord ependymoma resection. Although the rate of complete resections is similar to that in published series without 5-ALA, clinical results are better when using 5-ALA with a lower percentage of clinical deterioration.

9.
J Clin Pediatr Dent ; 33(3): 187-91, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19476089

RESUMEN

The objective of this study was to evaluate the clinical efficacy of 5% sodium hypochlorite solution for removal of stains caused by dental fluorosis in young patients. A clinical trial involved 33 patients with diffuse opacities on the enamel surfaces of maxillary incisors due to effects of dental fluorosis. The protocol of treatment 3 steps: (1) cleaning and enamel etching with 37% phosphoric acid in order to eliminate the layer that covers the fluorotic enamel surface and allow better penetration of the bleaching agent, (2) application of 5% sodium hypochlorite to remove stains caused by organic material, and (3) filling the opened micro-cavities with a light-cured, composite surface sealant to prevent restaining. The whiteness of the enamel lesions before and after treatment were expressed in L*, a*, and b* color space measurements using a Minolta Chroma Meter CR300. Analysis of parameters of [symbol:see text]E (L*, a*, b*) showed that changes were observed in the L* (brightness) and a* (redness), which paralleled the [symbol: see text]E differences. There was no significant difference in the b* (yellow) parameter. The technique described in this study appears to have advantages over other methods for improving the appearance of fluorotic lesions. It is simple, low cost, non invasive so the enamel keeps its structure, relatively rapid, and safe; it requires no special materials, and it can be used with safety on young permanent teeth.


Asunto(s)
Fluorosis Dental/complicaciones , Oxidantes/uso terapéutico , Hipoclorito de Sodio/uso terapéutico , Blanqueamiento de Dientes/métodos , Decoloración de Dientes/tratamiento farmacológico , Grabado Ácido Dental , Niño , Colorimetría , Femenino , Humanos , Masculino , Cementos de Resina , Decoloración de Dientes/etiología
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