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1.
Am J Hum Genet ; 107(3): 445-460, 2020 09 03.
Artículo en Inglés | MEDLINE | ID: mdl-32750315

RESUMEN

Tandem repeats are proposed to contribute to human-specific traits, and more than 40 tandem repeat expansions are known to cause neurological disease. Here, we characterize a human-specific 69 bp variable number tandem repeat (VNTR) in the last intron of WDR7, which exhibits striking variability in both copy number and nucleotide composition, as revealed by long-read sequencing. In addition, greater repeat copy number is significantly enriched in three independent cohorts of individuals with sporadic amyotrophic lateral sclerosis (ALS). Each unit of the repeat forms a stem-loop structure with the potential to produce microRNAs, and the repeat RNA can aggregate when expressed in cells. We leveraged its remarkable sequence variability to align the repeat in 288 samples and uncover its mechanism of expansion. We found that the repeat expands in the 3'-5' direction, in groups of repeat units divisible by two. The expansion patterns we observed were consistent with duplication events, and a replication error called template switching. We also observed that the VNTR is expanded in both Denisovan and Neanderthal genomes but is fixed at one copy or fewer in non-human primates. Evaluating the repeat in 1000 Genomes Project samples reveals that some repeat segments are solely present or absent in certain geographic populations. The large size of the repeat unit in this VNTR, along with our multiplexed sequencing strategy, provides an unprecedented opportunity to study mechanisms of repeat expansion, and a framework for evaluating the roles of VNTRs in human evolution and disease.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/genética , Esclerosis Amiotrófica Lateral/genética , Evolución Molecular , Secuencias Repetidas en Tándem/genética , Anciano , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/patología , Esclerosis Amiotrófica Lateral/patología , Expansión de las Repeticiones de ADN/genética , Femenino , Regulación de la Expresión Génica/genética , Humanos , Masculino , Repeticiones de Minisatélite/genética , Fenotipo , Especificidad de la Especie
2.
Curr Microbiol ; 77(7): 1184-1190, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32078007

RESUMEN

Probiotics are defined as live organisms that are able to confer health benefits to the host by improving their intestinal microbial balance. In the last decade, there has been an increasing interest to reveal health benefits associated with them. The objective of this study was to isolate indigenous probiotic organisms and assess their probiotic activity and therapeutic characteristics. The isolates were identified as Lactobacillus fermentum (isolates 2, 4, 6, 7, 8, and 9), Lactobacillus salivarius (isolate 13), and Lactobacillus plantarum (isolates 32 and 36). Five isolates showed growth at pH 2.5, while all isolates could grow at pH 8.5. All isolates showed good growth upto 5% NaCl concentration while two isolates showed growth in 7% NaCl concentration. All the isolates were susceptible to most of the broad-spectrum antibiotics. Cell-free suspensions from the isolates showed antimicrobial activity against the tested strains of Escherichia coli, Pseudomonas aeruginosa, Salmonella typhi, and Staphylococcus aureus. Two of the isolates 32 and 36 showed good revival after long-term storage, without any change in the morphology. Hence among all the other isolates these two isolates could have a good marketable potential. These strains can further be formulated into a probiotic drink that can be used as a health supplement.


Asunto(s)
Heces/microbiología , Lactobacillus , Leche/microbiología , Probióticos/farmacología , Animales , Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Bovinos , Lactobacillus/genética , Lactobacillus/fisiología , Pruebas de Sensibilidad Microbiana
3.
AJR Am J Roentgenol ; 212(1): 117-123, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30422713

RESUMEN

OBJECTIVE: The purpose of this study was to compare dual-energy CT (DECT) urography with a 50% reduced iodine dose to single-energy CT (SECT) urography with a standard iodine dose with respect to attenuation of renal vascular and urinary tract structures and with respect to image quality. SUBJECTS AND METHODS: The study included 62 patients undergoing evaluation of urinary tract lithiasis, tumor, or hematuria. Thirty-one patients underwent DECT urography with a 50% reduced iodine dose and reconstruction at 50 and 77 keV. These subjects were sex, age, and size matched to a group of 31 patients who underwent 120-kVp SECT urography with a standard iodine dose. The mean iodine dose was 22 g for DECT and 44 g for SECT. Attenuation was measured at seven locations in the renal arteries, renal veins, and urinary tract. Two reviewers subjectively scored the image quality parameters image noise, sharpness of urinary tract contours, enhancement of urinary structures, and streak artifacts. RESULTS: Mean DECT attenuation at 50 keV was the same as or greater than SECT attenuation at each of the seven locations. Measured image noise was highest at 50-keV DECT but was the same for 77-keV DECT and 120-kVp SECT. Mean subjective scores for DECT image quality parameters were the same as or higher than those of SECT, except for streak artifact and sharpness of urinary tract contours. CONCLUSION: DECT urography with a 50% reduced iodine dose may result in measured renal vascular and urinary tract attenuation the same as or higher than and image quality measurements and scores similar to those obtained with 120-kVp SECT urography with a standard iodine dose.


Asunto(s)
Medios de Contraste/administración & dosificación , Yohexol/administración & dosificación , Imagen Radiográfica por Emisión de Doble Fotón/métodos , Tomografía Computarizada por Rayos X/métodos , Ácidos Triyodobenzoicos/administración & dosificación , Urografía/métodos , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Interpretación de Imagen Radiográfica Asistida por Computador
4.
Cureus ; 14(2): e21819, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35291515

RESUMEN

Mycobacterium tuberculosis (TB) used to be one of the most widespread infections around the world. However, with improvements in sanitation, access to therapy, and increased public health efforts, TB has almost been eliminated from the developed world. While classically located in the lungs, infection can spread to distant sites from either late stage complications or as a sequelae from immunosuppression. In this paper, we present a case of a 53-year-old female who presented with nonspecific neurological complaints and multiple ring-enhancing lesions in the brain who was eventually diagnosed with central nervous system (CNS) tuberculosis after a lengthy workup despite following guideline-directed management. The purpose of this case report is to review an approach for ring-enhancing lesions and clinical considerations for central nervous system tuberculosis and add to the limited body of literature on the subject.

5.
Abdom Radiol (NY) ; 46(5): 1992-2002, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33079256

RESUMEN

PURPOSE: To evaluate the feasibility of CT perfusion performed during routine multiphase contrast-enhanced CT on a 160 mm wide-coverage 256-slice scanner in patients with pancreatic ductal adenocarcinoma (PDAC). METHODS: Fifty-seven patients had a CT perfusion acquisition during their routine multiphase CT. Perfusion was performed 5 to 42.5 s (15 passes at 2.5 s intervals) after intravenous contrast administration (4.2-5 ml/s), followed by pancreatic parenchymal and portal venous phases for clinical interpretation. Perfusion maps were generated and blood flow (BF), blood volume (BV), and permeability surface area product (PS) for tumor and uninvolved pancreas were calculated using deconvolution algorithms and compared to existing similar publications. Radiation dose information was recorded and size-specific dose estimate (SSDE) was calculated using body dimensions. RESULTS: Diagnostic quality of standard images was unaffected by performing the perfusion acquisition. Average tumor center BF was 20.8 ± 12.1 ml/100 g/min, BV 2.5 ± 2.1 ml/100 g and PS 15.5 ± 39.4 ml/100 g/min. Average pancreas BF was 90.8 ± 50.2 ml/100 g/min, BV 11.9 ± 4.3 ml/100 g and PS 33.6 ± 27.7 ml/100 g/min. For the perfusion acquisition, mean SSDE was 57 ± 11 mGy, CTDIvol 43 ± 6 mGy and DLP 685 ± 100 mGy-cm. CONCLUSION: Adding a perfusion CT acquisition to standard pancreatic CT protocol is feasible using a wide-detector 256-slice CT scanner and adds quantitative information while maintaining diagnostic quality of the standard of care examination. This novel protocol adds no time or cost to the examination and yields perfusion parameters that are comparable to existing literature using a separate dedicated perfusion protocol.


Asunto(s)
Adenocarcinoma , Neoplasias Pancreáticas , Estudios de Factibilidad , Humanos , Neoplasias Pancreáticas/diagnóstico por imagen , Imagen de Perfusión , Tomografía Computarizada por Rayos X
6.
Curr Diabetes Rev ; 16(7): 657-673, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31490762

RESUMEN

BACKGROUND: The increasing prevalence of reported cases of diabetes has evidently become a major global public health concern. Although diabetes management is possible by the administration of synthetic anti-diabetic agents, there are profound side-effects associated with their long-term usage. Hence there is a demand for safer alternatives which could be possibly formulated using specific yet common phytonutrients. OBJECTIVES: The main objective of this review is to describe the cellular mechanisms of phytonutrients as an alternative to commercially available synthetic anti-diabetic agents in the management of diabetes and related complications. Furthermore, the clinical evidence that supports this view is also highlighted. METHODOLOGY: An in-depth review of published literature was carried out to identify the most promising phytonutrients in the management of diabetes and related complications. RESULTS: A number of phytonutrients are reported to be potential anti-diabetic agents. Few examples include biguanides, resveratrol, lycopene, thymoquinone and quercetin. However, suitable formulations using these phytonutrients and their clinical trials are still underway. Most of the reported findings focus on one aspect of several biochemical processes e.g. enhancement of glucose utilization, antioxidation, induction of insulin production, antiglycation, etc. An in-depth study of phytonutrients with respect to functional, immunological as well as biochemical factors suggesting their efficacy, as well as safety in the management of diabetes, is rarely reported. CONCLUSION: Our study thus highlights the abundance of clinical evidence of the efficiency of phytonutrients, and at the same time, the scarcity of clinically approved and marketed phytonutrients, as drugs, for the management of diabetes and related complications.


Asunto(s)
Complicaciones de la Diabetes/prevención & control , Diabetes Mellitus/terapia , Fitoquímicos/uso terapéutico , Complicaciones de la Diabetes/etiología , Diabetes Mellitus/dietoterapia , Diabetes Mellitus/tratamiento farmacológico , Dieta , Humanos , Hipoglucemiantes/efectos adversos , Hipoglucemiantes/uso terapéutico
7.
Abdom Radiol (NY) ; 45(8): 2370-2377, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32333072

RESUMEN

PURPOSE: To evaluate feasibility of a wide detector liver CT protocol with three acquisitions in the hepatic arterial phase. METHODS: Forty-one patients with cirrhosis prospectively underwent a wide detector axial liver CT protocol. Three 16 cm axial liver acquisitions were obtained during a single breath hold at peak aortic enhancement plus 10, 20, and 25 s. Two readers working separately scored overall exam quality, identified hyperenhancing lesions, and subjectively scored and ranked relative lesion conspicuity. Objective lesion enhancement was measured and CNR calculated. Data were analyzed using a generalized linear models and Tukey's post hoc testing. RESULTS: Seventy-one hyperenhancing lesions were identified with average size of 1.8 cm (range 0.4-9.6 cm). The two readers separately identified 60 and 54 lesions on the 10 s arterial acquisition, 70 and 67 on the 20 s, and 52 and 51 on the 25 s. The readers determined all exams had diagnostic image quality. Subjective ranking of lesion conspicuity was greatest at 20 s in 62% of lesions but was greatest at 10 or 25 s in 38%. CNR was highest at 20 s in 58% of lesions but was highest at 10 or 25 s in 42%. Overall, there was no significant difference in mean CNR between the three arterial acquisitions. CONCLUSION: A wide detector axial liver CT protocol with three acquisitions in the hepatic arterial phase is technologically feasible and results in diagnostic image quality. With this protocol, peak subjective and objective hyperenhancing lesion conspicuity may be earlier or later than 20 s in up to 40% of lesions.


Asunto(s)
Neoplasias Hepáticas , Interpretación de Imagen Radiográfica Asistida por Computador , Medios de Contraste , Estudios de Factibilidad , Humanos , Cirrosis Hepática/diagnóstico por imagen , Neoplasias Hepáticas/diagnóstico por imagen , Tomografía Computarizada por Rayos X
8.
Mol Ther Nucleic Acids ; 19: 572-580, 2020 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-31927330

RESUMEN

Gene knockdown using short hairpin RNAs (shRNAs) is a promising strategy for targeting dominant mutations; however, delivering too much shRNA can disrupt the processing of endogenous microRNAs (miRNAs) and lead to toxicity. Here, we sought to understand the effect that excessive shRNAs have on muscle miRNAs by treating mice with recombinant adeno-associated viral vectors (rAAVs) that produce shRNAs with 19-nt or 21-nt stem sequences. Small RNA sequencing of their muscle and liver tissues revealed that shRNA expression was highest in the heart, where mice experienced substantial cardiomyopathy when shRNAs accumulated to 51.2% ± 13.7% of total small RNAs. With the same treatment, shRNAs in other muscle tissues reached only 12.1% ± 5.0% of total small RNAs. Regardless of treatment, the predominant heart miRNAs remained relatively stable across samples. Instead, the lower-expressed miR-451, one of the few miRNAs processed independently of Dicer, changed in relation to shRNA level and toxicity. Our data suggest that a protective mechanism exists in cardiac tissue for maintaining the levels of most miRNAs in response to shRNA delivery, in contrast with what has been shown in the liver. Quantifying miRNA profiles after excessive shRNA delivery illuminates the host response to rAAV-shRNA, allowing for safer and more robust therapeutic gene knockdown.

9.
Chemosphere ; 207: 255-266, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29803157

RESUMEN

Chromium (VI) is one of the most common environmental contaminant due to its tremendous industrial applications. It is non-biodegradable as it is a heavy metal, and hence, of major concern. Therefore, it is pertinent that the remediation method should be such that brings chromium within permissible limits before the effluent is discharged. Several different strategies are adopted by microorganisms for Cr (VI) removal mostly involving biosorption and biotransformation or both. These mechanisms are based on the surface nature of the biosorbent and the availability of reductants. This review article focuses on chromium pollution problem, its chemistry, sources, effects, remediation strategies by biological agents and detailed chromium detoxification mechanism in microbial cell. A summary of applied in situ and ex situ chromium bioremediation technologies is also listed. This can be helpful for developing technologies to be more efficient for Cr (VI) removal thereby bridging the gap between laboratory findings and industrial application for chromium remediation.


Asunto(s)
Biotransformación/fisiología , Cromo/química
10.
J Biomol Screen ; 10(8): 788-94, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16234350

RESUMEN

A microfluidic assay was developed for screening botulinum neurotoxin serotype A (BoNT-A) by using a fluorescent resonance energy transfer (FRET) assay. Molded silicone microdevices with integral valves, pumps, and reagent reservoirs were designed and fabricated. Electrical and pneumatic control hardware were constructed, and software was written to automate the assay protocol and data acquisition. Detection was accomplished by fluorescence microscopy. The system was validated with a peptide inhibitor, running 2 parallel assays, as a feasibility demonstration. The small footprint of each bioreactor cell (0.5 cm2) and scalable fluidic architecture enabled many parallel assays on a single chip. The chip is programmable to run a dilution series in each lane, generating concentration-response data for multiple inhibitors. The assay results showed good agreement with the corresponding experiments done at a macroscale level. Although the system has been developed for BoNT-A screening, a wide variety of assays can be performed on the microfluidic chip with little or no modification.


Asunto(s)
Bioensayo/métodos , Toxinas Botulínicas Tipo A/análisis , Microfluídica/instrumentación , Bioensayo/instrumentación , Estudios de Factibilidad , Microquímica/instrumentación , Miniaturización
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