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1.
Genes Cells ; 26(11): 927-937, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34487583

RESUMEN

Bacteria exhibit chemotaxis by controlling flagellar rotation to move toward preferred places or away from nonpreferred places. The change in rotation is triggered by the binding of the chemotaxis signaling protein CheY-phosphate (CheY-P) to the C-ring in the flagellar motor. Some specific bacteria, including Vibrio spp. and Shewanella spp., have a single transmembrane protein called ZomB. ZomB is essential for controlling the flagellar rotational direction in Shewanella putrefaciens and Vibrio parahaemolyticus. In this study, we confirmed that the zomB deletion results only in the counterclockwise (CCW) rotation of the motor in Vibrio alginolyticus as previously reported in other bacteria. We found that ZomB is not required for a clockwise-locked phenotype caused by mutations in fliG and fliM, and that ZomB is essential for CW rotation induced by overproduction of CheY-P. Purified ZomB proteins form multimers, suggesting that ZomB may function as a homo-oligomer. These observations imply that ZomB interacts with protein(s) involved in either flagellar motor rotation, chemotaxis, or both. We provide the evidence that ZomB is a new player in chemotaxis and is required for the rotational control in addition to CheY in Vibrio alginolyticus.


Asunto(s)
Proteínas de Escherichia coli , Vibrio alginolyticus , Proteínas Bacterianas/genética , Quimiotaxis , Flagelos , Proteínas de la Membrana/genética
2.
Mol Pharm ; 19(7): 2335-2342, 2022 07 04.
Artículo en Inglés | MEDLINE | ID: mdl-35604773

RESUMEN

Alcoholic liver disease (ALD) has a significant impact on human health and is one of the leading causes of liver disease mortality. The early and exact diagnosis of ALD is very important since the early stage of disease progression can be reversible. Although ALD can be evaluated by ultrasound, CT, or MRI, there is still no imaging technique sufficient in the diagnosis of early-stage ALD. Of the current studies, epigenetic modulation plays a significant role in the development and progression of ALD. In this work, we evaluate whether BRDs play a vital role in the early-stage ALD using our new PET imaging probe of BET proteins, [11C]CW22. PET/CT imaging of [11C]CW22 and [18F]FDG was used to identify early-stage lesions of livers and brains in the mice model. We found that the average uptake values of livers and brains in early-stage ALD were significantly increased for [11C]CW22 PET/CT imaging but only slightly changed in [18F]FDG PET/CT imaging. Consistently, we also found that BRD 3, 4 protein expression levels were significantly higher in the liver and brain tissues of early-stage ALD. Furthermore, through Pmod software, we found that [11C]CW22 PET/CT uptakes in the brain stem, cerebellum, and midbrain were significantly up-regulated in the early-stage ALD. In conclusion, BRDs were important mediators of damage in early-stage ALD. [11C]CW22 PET/CT imaging can detect the early-phase alcohol-induced damage of livers and brains, which will likely lead to human trials in the future.


Asunto(s)
Fluorodesoxiglucosa F18 , Hepatopatías Alcohólicas , Animales , Encéfalo/metabolismo , Fluorodesoxiglucosa F18/metabolismo , Hepatopatías Alcohólicas/diagnóstico por imagen , Hepatopatías Alcohólicas/patología , Ratones , Tomografía Computarizada por Tomografía de Emisión de Positrones , Tomografía de Emisión de Positrones/métodos
3.
J Environ Manage ; 133: 293-301, 2014 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-24412592

RESUMEN

The objective of this study was to investigate the effect of the feed-to-microbe (F/M) ratios on anaerobic digestion of Chinese cabbage waste (CCW) generated from a kimchi factory. The batch test was conducted for 96 days under mesophilic (36.5 °C) (Experiment I) and thermophilic (55 °C) conditions (Experiment II) at F/M ratios of 0.5, 1.0 and 2.0. The first-order kinetic model was evaluated for methane yield. The biogas yield in terms of volatile solids (VS) added increased from 591 to 677 mL/g VS under mesophilic conditions and 434 to 639 mL/g VS under thermophilic conditions when the F/M ratio increased from 0.5 to 2.0. Similarly, the volumetric biogas production increased from 1.479 to 6.771 L/L under mesophilic conditions and from 1.086 to 6.384 L/L under thermophilic conditions when F/M ratio increased from 0.5 to 2.0. The VS removal increased from 59.4 to 75.6% under mesophilic conditions and from 63.5 to 78.3% under thermophilic conditions when the F/M ratio increased from 0.5 to 2.0. The first-order kinetic constant (k, 1/day) decreased under the mesophilic temperature conditions and increased under thermophilic conditions when the F/M ratio increased from 0.5 to 2.0. The difference between the experimental and predicted methane yield was in the range of 3.4-14.5% under mesophilic conditions and in the range of 1.1-3.0% under thermophilic conditions. The predicted methane yield derived from the first-order kinetic model was in good agreement with the experimental results.


Asunto(s)
Anaerobiosis , Brassica/metabolismo , Reactores Biológicos , Cinética
4.
Conserv Physiol ; 12(1): coae028, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38765884

RESUMEN

Blood biochemistry represents a minimally invasive tool for monitoring sea turtle health, assessing injured sea turtles and supporting conservation strategies. In Grenada, West Indies, plasma biochemical variables were examined in 33 nesting leatherback (Dermochelys coriacea), 49 foraging green (Chelonia mydas), 49 foraging hawksbill (Eretmochelys imbricata) and 12 nesting hawksbill sea turtles sampled between 2017 and 2022. Plasma biochemistry reference intervals are described herein except for nesting hawksbills, which are represented by descriptive statistics due to the low sample size. Select analyte concentrations were positively correlated with curved carapace length in leatherbacks (chloride), green turtles (total protein, albumin and globulin) and foraging hawksbills (total protein, albumin and phosphorus). Cholesterol (7.8 mmol/l ± 1.6 SD) and triglyceride (6.9 mmol/l ± 1.9 SD) concentrations were significantly higher in leatherbacks compared to foraging green turtles, foraging hawksbills and nesting hawksbills (P < 0.001 for all). Cholesterol was significantly higher in nesting hawksbills compared to foraging green turtles (P = 0.050) and foraging hawksbills (P = 0.050). Foraging hawksbills demonstrated significantly higher aspartate transaminase activities than leatherbacks (P = 0.002), green turtles (P = 0.009) and nesting hawksbills (P < 0.001). Biochemical results provide baseline population health data and support guidance for treatments during clinical sea turtle rehabilitation efforts. They also provide insight into species-specific physiologic differences and preludes further studies to better characterize the impacts of life-stage class on biochemistry reference intervals to better support wild sea turtle populations in Grenada.

5.
Curr Res Struct Biol ; 4: 59-67, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35345452

RESUMEN

Flagella are necessary for bacterial movement and contribute to various aspects of virulence. They are complex cylindrical structures built of multiple molecular rings with self-assembly properties. The flagellar rotor is composed of the MS-ring and the C-ring. The FliG protein of the C-ring is central to flagellar assembly and function due to its roles in linking the C-ring with the MS-ring and in torque transmission from stator to rotor. No high-resolution structure of an assembled C-ring has been resolved to date, and the conformation adopted by FliG within the ring is unclear due to variations in available crystallographic data. Here, we use molecular dynamics (MD) simulations to study the conformation and dynamics of FliG in different states of assembly, including both in physiologically relevant and crystallographic lattice environments. We conclude that the linker between the FliG N-terminal and middle domain likely adopts an extended helical conformation in vivo, in contrast with the contracted conformation observed in some previous X-ray studies. We further support our findings with integrative model building of full-length FliG and a FliG ring model that is compatible with cryo-electron tomography (cryo-ET) and electron microscopy (EM) densities of the C-ring. Collectively, our study contributes to a better mechanistic understanding of the flagellar rotor assembly and its function.

6.
Bioresour Technol ; 337: 125487, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34320766

RESUMEN

A Saccharomyces cerevisiae strain CCW12OE was constructed by overexpressing CCW12 in a previously reported strain WXY70 harboring six xylose utilization genes. CCW12OE produced an optimal ethanol yield of 98.8% theoretical value within 48 h in a simulated corn stover hydrolysate. CCW12OEwas comprehensively evaluated for ethanol production in Miscanthus, maize and corncob hydrolysates, among which a 96.1% theoretical value was achieved within 12 h in corncob hydrolysates. Under normal growth conditions, CCW12OE did not display altered cell morphology; however, in the presence of acetate, CCW12OE maintained relatively intact cell structure and increased cell wall thickness by nearly 50%, while WXY70 had abnormal cell morphology and reduced cell wall thickness by nearly 50%. Besides, CCW12OE had higher fermentation capacity than that of WXY70 in undetoxified and detoxified hydrolysates with both aerobic and anaerobic conditions, demonstrating that CCW12 overexpression alone exhibits improved stress resistance and better fermentation performance.


Asunto(s)
Etanol , Saccharomyces cerevisiae , Fermentación , Lignina/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Xilosa
7.
Trends Ecol Evol ; 36(11): 964-967, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34561090

RESUMEN

Diversity is a key driver of scientific innovation, yet fields in science, technology, engineering, and mathematics (STEM) have struggled to retain diverse communities. Research suggests that fostering a sense of belonging is critical for retaining diversity. We propose an iterative process that aims to improve sense of belonging among laboratory (lab) members through self-reflection and community collective action.


Asunto(s)
Ciencia , Ingeniería , Matemática , Tecnología
8.
Biodivers Data J ; 9: e67085, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-36761998

RESUMEN

Background: Limoniidae is one of the most species-rich Dipteran families, with 661 reported species in Europe. Despite the fact that the European limoniid crane fly fauna has been studied ever since Carolus Linnaeus, it is still poorly known. New information: In this study, we summarise the taxonomic and faunistic studies of European Limoniidae, which described new species and reported first country records, between 2010 and 2020. We also report occurrence data of 244 Limoniidae species which represent the first country records or conformational records from various European countries, as we report ten species from Albania, one from Austria, thirty-seven from Belarus, five from Belgium, two from Bulgaria, two from Estonia, six from Finland, seven from France, fourteen from Greece, sixteen from Hungary, two from Iceland, six from Italy, ten from Latvia, one from Malta, nine from Montenegro, two from The Netherlands, ten from North Macedonia, forty-two from Norway, one from Poland, five from Portugal, twenty from Romania, thirty-eight from Serbia, six from Slovenia, five from Spain and seven species from Sweden for the first time. From the European territory of Russia, we report twenty-eight species from Central European Russia, seventy-two from East European Russia, fifteen from North European Russia, one from Northwest European Russia and seven from North Caucasus for the first time. Confirmatory records and corrigenda are also included.

9.
Plant Methods ; 13: 66, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28794796

RESUMEN

BACKGROUND: Common cutworm (CCW; Spodoptera litura Fabricius) is a major leaf-feeding pest of soybean in Asia. The previous methods of measuring antixenosis against CCW using adult plant under field or net-room conditions were time-consuming, labor-intensive and precision-inferior. To solve the problems, this study aimed at (i) establishing a high-throughput phenotyping method for evaluating antixenosis against CCW at early seedling stage, (ii) using the procedure to evaluate the antixenosis of an insect-resistant versus -susceptible germplasm population (IRSGP), (iii) validating the proposed method through comparing the results with the historical phenotypic data and phenotyping-genotyping consistency data using PAV (presence/absence variation) markers linked with the identified loci CCW-1 and CCW-2, (iv) and evaluating the efficiency of the novel method through comparisons to the previous methods. RESULTS: A dynamic and efficient evaluation procedure characterized with using V1 stage soybean seedlings infested with third-instar larvae in a micro-net-room in greenhouse with damaged leaf percentage (DLP) as indicator was established and designated V1TMD method. The middle term testing stage is the best dates for identifying resistant and susceptible accessions. The results from the V1TMD method were relatively stable, precise and accurate in comparison with the previous method with the detected most resistant and susceptible accessions consistent to the previous results. The DLP values differentiated obviously to coincide with the resistant and susceptible alleles of the PAV markers Gm07PAV0595 and Gm07PAV0389 tightly linked to the two resistance-related loci, CCW-1 and CCW-2, respectively, in IRSGP. Thus V1TMD is a high-throughput phenotyping method with its estimated efficiency 12 times and period shortening 4 times of those of the previous method. CONCLUSION: A dynamic and efficient V1TMD method for testing antixenosis against CCW was established, with highly resistant and highly susceptible accessions as standard checks and DLP as indicator. The method is remarkably quick, highly reproducible, and capable of testing large samples, therefore, is a high-throughput phenotyping method.

10.
Am J Ophthalmol Case Rep ; 7: 115-119, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29260093

RESUMEN

PURPOSE: Superior oblique myokymia (SOM) is a rare eye movement disorder characterized by unilateral oscillopsia and binocular diplopia. Our study aimed to better understand SOM using infrared oculography. METHODS: We examined and recorded five patients with SOM. RESULTS: Binocular infrared oculography showed that in primary gaze, all patients exhibited torsional oscillations, which worsened in infraduction and abduction and improved in supraduction and adduction. Saccades showed increased downward saccade amplitudes but normal peak velocities. During fixation in primary gaze, removal of target led to extorsion and supraduction, unmasking underlying superior oblique weakness. CONCLUSIONS AND IMPORTANCE: Our data suggest both weakness and activity-dependent hyperactivity of the trochlear motor unit, supporting a model of injury followed by aberrant regeneration.

11.
Mayo Clin Proc Innov Qual Outcomes ; 1(1): 100-110, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30225406

RESUMEN

OBJECTIVE: To develop and validate a phenotyping algorithm for the identification of patients with type 1 and type 2 diabetes mellitus (DM) preoperatively using routinely available clinical data from electronic health records. PATIENTS AND METHODS: We used first-order logic rules (if-then-else rules) to imply the presence or absence of DM types 1 and 2. The "if" clause of each rule is a conjunction of logical and, or predicates that provides evidence toward or against the presence of DM. The rule includes International Classification of Diseases, Ninth Revision, Clinical Modification diagnostic codes, outpatient prescription information, laboratory values, and positive annotation of DM in patients' clinical notes. This study was conducted from March 2, 2015, through February 10, 2016. The performance of our rule-based approach and similar approaches proposed by other institutions was evaluated with a reference standard created by an expert reviewer and implemented for routine clinical care at an academic medical center. RESULTS: A total of 4208 surgical patients (mean age, 52 years; males, 48%) were analyzed to develop the phenotyping algorithm. Expert review identified 685 patients (16.28% of the full cohort) as having DM. Our proposed method identified 684 patients (16.25%) as having DM. The algorithm performed well-99.70% sensitivity, 99.97% specificity-and compared favorably with previous approaches. CONCLUSION: Among patients undergoing surgery, determination of DM can be made with high accuracy using simple, computationally efficient rules. Knowledge of patients' DM status before surgery may alter physicians' care plan and reduce postsurgical complications. Nevertheless, future efforts are necessary to determine the effect of first-order logic rules on clinical processes and patient outcomes.

12.
AMIA Annu Symp Proc ; 2016: 1860-1869, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-28269945

RESUMEN

Depression, despite its high prevalence, remains severely under-diagnosed across the healthcare system. This demands the development of data-driven approaches that can help screen patients who are at a high risk of depression. In this work, we develop depression risk prediction models that incorporate disease co-morbidities using logistic regression with Elastic Net. Using data from the one million twelve-year longitudinal cohort from Korean National Health Insurance Services (KNHIS), our model achieved an Area Under the Curve (AUC) of the Receiver Operating Characteristic (ROC) of 0.7818, compared to a traditional logistic regression model without co-morbidity analysis (AUC of 0.6992). We also showed co-morbidity adjusted Odds Ratios (ORs), which may be more accurate independent estimate of each predictor variable. In conclusion, inclusion of co-morbidity analysis improved the performance of depression risk prediction models.


Asunto(s)
Comorbilidad , Depresión/epidemiología , Programas Nacionales de Salud , Adulto , Área Bajo la Curva , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Prevalencia , Curva ROC , República de Corea/epidemiología , Riesgo
13.
Neuroscience ; 260: 12-22, 2014 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-24342565

RESUMEN

To maintain perception of the world around us during body motion, the brain must update the spatial presentation of visual stimuli, known as space updating. Previous studies have demonstrated that vestibular signals contribute to space updating. Nonetheless, when being passively rotated in the dark, the ability to keep track of a memorized earth-fixed target (EFT) involves learning mechanism(s). We tested whether such learning generalizes across different EFT eccentricities. Furthermore, we ascertained whether learning transfers to similar target eccentricities but in the opposite direction. Participants were trained to predict the position of an EFT (located at 45° to their left) while being rotated counterclockwise (i.e., they press a push button when they perceived that their body midline have cross the position of the target). Overall, the results indicated that learning transferred to other target eccentricity (30° and 60°) for identical body rotation direction. In contrast, vestibular learning partly transferred to target location's matching body rotation but in the opposite rotation direction. Generalization of learning implies that participants do not adopt cognitive strategies to improve their performance during training. We argue that the brain learned to use vestibular signals for space updating. Generalization of learning while being rotated in the opposite direction implies that some parts of the neural networks involved in space updating is shared between trained and untrained direction.


Asunto(s)
Generalización Psicológica , Aprendizaje , Percepción de Movimiento , Percepción Espacial , Adulto , Humanos , Rotación , Adulto Joven
14.
Respir Physiol Neurobiol ; 192: 1-6, 2014 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-24316219

RESUMEN

PURPOSE: We have developed a software that automatically calculates respiratory effort indices, including intrinsic end expiratory pressure (PEEPi) and esophageal pressure-time product (PTPeso). MATERIALS AND METHODS: The software first identifies respiratory periods. Clean signals are averaged to provide a reference mean cycle from which respiratory parameters are extracted. The onset of the inspiratory effort is detected automatically by looking backward from the onset of inspiratory flow to the first point where the esophageal pressure derivative is equal to zero (inflection point). PEEPi is derived from this point. Twenty-three recordings from 16 patients were analyzed with the algorithm and compared with experts' manual analysis of signals: 15 recordings were performed during spontaneous breathing, 1 during non-invasive mechanical ventilation, and 7 under both conditions. RESULTS: For all values, the coefficients of determinations (r(2)) exceeded 0.94 (p<0.001). The bias (mean difference) between PEEPi calculated by hand and automatically was -0.26±0.52cmH2O during spontaneous breathing and the precisions (standard deviations of the differences) was 0.52cmH2O with limits of agreement of 0.78 and -1.30cmH2O. The mean difference between PTPeso calculated by hand and automatically was -0.38±1.42cmH2Os/cycle with limits of agreement of 2.46 and -3.22cmH2Os/cycle. CONCLUSIONS: Our program provides a reliable method for the automatic calculation of PEEPi and respiratory effort indices, which may facilitate the use of these variables in clinical practice. The software is open source and can be improved with the development and validation of new respiratory parameters.


Asunto(s)
Procesamiento Automatizado de Datos/métodos , Respiración de Presión Positiva Intrínseca/diagnóstico , Respiración con Presión Positiva , Respiración , Músculos Respiratorios/fisiología , Programas Informáticos , Adolescente , Adulto , Factores de Edad , Anciano , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Adulto Joven
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