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1.
Biotechnol Biofuels Bioprod ; 17(1): 20, 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38321504

RESUMEN

BACKGROUND: Cost-effective production of biofuels from lignocellulose requires the fermentation of D-xylose. Many yeast species within and closely related to the genera Spathaspora and Scheffersomyces (both of the order Serinales) natively assimilate and ferment xylose. Other species consume xylose inefficiently, leading to extracellular accumulation of xylitol. Xylitol excretion is thought to be due to the different cofactor requirements of the first two steps of xylose metabolism. Xylose reductase (XR) generally uses NADPH to reduce xylose to xylitol, while xylitol dehydrogenase (XDH) generally uses NAD+ to oxidize xylitol to xylulose, creating an imbalanced redox pathway. This imbalance is thought to be particularly consequential in hypoxic or anoxic environments. RESULTS: We screened the growth of xylose-fermenting yeast species in high and moderate aeration and identified both ethanol producers and xylitol producers. Selected species were further characterized for their XR and XDH cofactor preferences by enzyme assays and gene expression patterns by RNA-Seq. Our data revealed that xylose metabolism is more redox balanced in some species, but it is strongly affected by oxygen levels. Under high aeration, most species switched from ethanol production to xylitol accumulation, despite the availability of ample oxygen to accept electrons from NADH. This switch was followed by decreases in enzyme activity and the expression of genes related to xylose metabolism, suggesting that bottlenecks in xylose fermentation are not always due to cofactor preferences. Finally, we expressed XYL genes from multiple Scheffersomyces species in a strain of Saccharomyces cerevisiae. Recombinant S. cerevisiae expressing XYL1 from Scheffersomyces xylosifermentans, which encodes an XR without a cofactor preference, showed improved anaerobic growth on xylose as the primary carbon source compared to S. cerevisiae strain expressing XYL genes from Scheffersomyces stipitis. CONCLUSION: Collectively, our data do not support the hypothesis that xylitol accumulation occurs primarily due to differences in cofactor preferences between xylose reductase and xylitol dehydrogenase; instead, gene expression plays a major role in response to oxygen levels. We have also identified the yeast Sc. xylosifermentans as a potential source for genes that can be engineered into S. cerevisiae to improve xylose fermentation and biofuel production.

2.
Phys Ther ; 104(4)2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38243411

RESUMEN

OBJECTIVE: The objective of this study was to compare the lexical sophistication of personal statements submitted by professional physical therapist education program applicants with those generated by OpenAI's Chat Generative Pretrained Transformer (ChatGPT). METHODS: Personal statements from 152 applicants and 20 generated by ChatGPT were collected, all in response to a standardized prompt. These statements were coded numerically, then analyzed with recurrence quantification analyses (RQAs). RQA indices including recurrence, determinism, max line, mean line, and entropy were compared with t-tests. A receiver operating characteristic curve analysis was used to examine discriminative validity of RQA indices to distinguish between ChatGPT and human-generated personal statements. RESULTS: ChatGPT-generated personal statements exhibited higher recurrence, determinism, mean line, and entropy values than did human-generated personal statements. The strongest discriminator was a 13.04% determinism rate, which differentiated ChatGPT from human-generated writing samples with 70% sensitivity and 91.4% specificity (positive likelihood ratio = 8.14). Personal statements with determinism rates exceeding 13% were 8 times more likely to have been ChatGPT than human generated. CONCLUSION: Although RQA can distinguish artificial intelligence (AI)-generated text from human-generated text, it is not absolute. Thus, AI introduces additional challenges to the authenticity and utility of personal statements. Admissions committees along with organizations providing guidelines in professional physical therapist education program admissions should reevaluate the role of personal statements in applications. IMPACT: As AI-driven chatbots like ChatGPT complicate the evaluation of personal statements, RQA emerges as a potential tool for admissions committees to detect AI-generated statements.


Asunto(s)
Educación Profesional , Fisioterapeutas , Humanos , Inteligencia Artificial , Hospitalización , Curva ROC
3.
Ann Med ; 55(2): 2295402, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38142049

RESUMEN

OBJECTIVE: Athletic performance can be enhanced immediately after an isometric warm-up, a phenomenon termed post-activation performance enhancement (PAPE). While isometric warm-ups can improve lower extremity sprint and jump performance, neck-specific isometric warm-ups need development and validation for mild traumatic brain disorders and neck pain. This study examined acute effects of isometric warm-ups on neck performance and morphology. METHODS: Arm 1: Twenty-six adults (13 M:13F) completed neck performance testing before and after a 10-minute neck isometric warm-up or stationary bike (sham) between two visits. Testing included visual-motor reaction time, peak force, rate of force development, force steadiness, and force replication/proprioception measured by a 6-axis load cell. An inclinometer assessed range-of-motion. Paired t-tests and two-way ANOVA examined effects of neck/bike warm-up and interaction effects, respectively. Arm 2: 24 adults (11 M:13F) completed ultrasound scans of cervical muscles: before 20-minute rest (sham), and before/after a 5-min neck isometric warm-up. Longus colli cross-sectional area and sternocleidomastoid/upper trapezius thickness and stiffness, and cervical extensors thickness was assessed. One-way ANOVA compared morphological values at sham, before, and after warm-up. Significance was set at p < 0.05. RESULTS: Isometric neck warm-up increased rate of force development in flexion (p = 0.022), extension (p = 0.001-0.003), right lateral flexion (p = 0.004-0.032), left lateral flexion (p = 0.005-0.014), while peak force improved only in left lateral flexion (p = 0.032). Lateral flexion range-of-motion increased after neck warm-up (p = 0.003-0.026). Similarly, longus colli cross-sectional area (p = 0.016) and sternocleidomastoid thickness (p = 0.004) increased. CONCLUSIONS: Increased neck performance characteristics and morphology are likely due to PAPE effects of isometric neck warm-up. For coaches and athletes, simple isometric contractions could be added to existing warm-ups to reduce prevalence, incidence, and severity of mild traumatic brain injuries and neck pain.


Asunto(s)
Dolor de Cuello , Cuello , Adulto , Humanos , Dolor de Cuello/diagnóstico por imagen , Cuello/diagnóstico por imagen , Músculos del Cuello/diagnóstico por imagen , Músculos del Cuello/anatomía & histología , Músculos del Cuello/fisiología , Contracción Isométrica/fisiología , Ultrasonografía
4.
J Allied Health ; 52(3): e93-e98, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37728356

RESUMEN

PURPOSE: Machine learning algorithms provide methods by which patterns in admissions data may be discovered that predict admissions yields in education programs. We used a chi-square automatic interaction detection (CHAID) analysis to examine characteristics that predict applicants most likely to matriculate into a physical therapy program after being admitted. METHODS: Data from applicants admitted to our physical therapy program from the 2015-2016 through 2021-2022 admissions cycles were evaluated (n=413). Variables included applicants' ages, grade point averages, graduate record examination (GRE) scores, admissions and behavioral interview scores, sex/gender, race/ethnicity, home state classification, undergraduate major classification, institutional classification, socioeconomic status, and first generation to college status. A CHAID algorithm identified which variables predicted matriculation after being admitted. RESULTS: Overall, 47.2% of admitted applicants matriculated. The CHAID algorithm generated a 3-level model with 5 terminal nodes that classified matriculants with 64.9% accuracy. Applicants more likely to matriculate than to decline an admission offer included in-state applicants and White/Caucasian border-state/out-of-state applicants with GPAs below 3.65. DISCUSSION: While findings are program-specific, the CHAID analysis provides a tool to analyze admissions data that admissions committees may use to analyze their admissions processes and outcomes.


Asunto(s)
Algoritmos , Instituciones Académicas , Humanos , Universidades , Aprendizaje Automático , Modalidades de Fisioterapia
5.
Yeast ; 40(9): 395-400, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37526396

RESUMEN

Humans rely on the ability of budding yeasts to grow without oxygen in industrial scale fermentations that produce beverages, foods, and biofuels. Oxygen is deeply woven into the energy metabolism and biosynthetic capabilities of budding yeasts. While diverse ecological habitats may provide wide varieties of different carbon and nitrogen sources for yeasts to utilize, there is no direct substitute for molecular oxygen, only a range of availability. Understanding how a small subset of budding yeasts evolved the ability to grow without oxygen could expand the set of useful species in industrial scale fermentations as well as provide insight into the cryptic field of yeast ecology. However, we still do not yet appreciate the full breadth of species that can growth without oxygen, what genes underlie this adaptation, and how these genes have evolved.


Asunto(s)
Saccharomycetales , Levaduras , Humanos , Anaerobiosis , Levaduras/metabolismo , Saccharomyces cerevisiae/genética , Saccharomycetales/genética , Saccharomycetales/metabolismo , Fermentación
7.
Research (Wash D C) ; 6: 0065, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36930761

RESUMEN

Multimode fibers hold great promise to advance data rates in optical communications but come with the challenge to compensate for modal crosstalk and mode-dependent losses, resulting in strong distortions. The holographic measurement of the transmission matrix enables not only correcting distortions but also harnessing these effects for creating a confidential data connection between legitimate communication parties, Alice and Bob. The feasibility of this physical-layer-security-based approach is demonstrated experimentally for the first time on a multimode fiber link to which the eavesdropper Eve is physically coupled. Once the proper structured light field is launched at Alice's side, the message can be delivered to Bob, and, simultaneously, the decipherment for an illegitimate wiretapper Eve is destroyed. Within a real communication scenario, we implement wiretap codes and demonstrate confidentiality by quantifying the level of secrecy. Compared to an uncoded data transmission, the amount of securely exchanged data is enhanced by a factor of 538. The complex light transportation phenomena that have long been considered limiting and have restricted the widespread use of multimode fiber are exploited for opening new perspectives on information security in spatial multiplexing communication systems.

8.
Clin Biomech (Bristol, Avon) ; 104: 105929, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36893524

RESUMEN

BACKGROUND: Despite widespread use of return to sport testing following anterior cruciate ligament reconstruction, studies suggest inadequacy in current testing criteria, such as limb symmetry index calculations, to determine athletes' readiness to return to play. Recurrence quantification analysis, an emerging non-linear data analysis tool, may reveal subtle neuromuscular differences between the injured and uninjured limb that are not captured by traditional testing. We hypothesized that isokinetic torque curve data of the injured limb would demonstrate lower determinism and entropy as compared to the uninjured limb. METHODS: 102 patients (44 M, 58F, 10 ± 1 months post-anterior cruciate ligament reconstruction) underwent isokinetic quadriceps strength testing using a HumacNorm dynamometer. Patients completed maximum effort knee extension and flexion at 60°/sec. Data were post-processed with a MATLAB CRQA Graphical User Interface and determinism and entropy values were extracted. Paired-sample t-tests (α = 0.05) were used to compare data from the injured and uninjured limb. FINDINGS: Determinism and entropy values in the torque curves were lower in the injured limb than the uninjured limb (p < 0.001). Our findings indicate there is less predictability and complexity present in the torque signals of injured limbs. INTERPRETATION: Recurrence quantification analysis can be used to assess neuromuscular differences between limbs in patients who have undergone anterior cruciate ligament reconstruction. Our findings offer further evidence that there are changes to the neuromuscular system which persist following reconstruction. Further investigation is needed to establish thresholds of determinism and entropy values needed for safe return to sport and to evaluate the utility of recurrence quantification analysis as a return to sport criterion.


Asunto(s)
Lesiones del Ligamento Cruzado Anterior , Ligamento Cruzado Anterior , Humanos , Ligamento Cruzado Anterior/cirugía , Lesiones del Ligamento Cruzado Anterior/cirugía , Volver al Deporte , Fuerza Muscular , Extremidad Inferior , Músculo Cuádriceps
9.
Am J Manag Care ; 28(11): 566-571, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36374614

RESUMEN

OBJECTIVES: Drug-drug interactions (DDIs) are among the most common causes of adverse drug reactions and are further complicated by genetic variants of drug-metabolizing enzymes. The aim of this study is to quantify and describe potential DDIs, drug-gene interactions (DGIs), and drug-drug-gene interactions (DDGIs) in a community-based population. STUDY DESIGN: This was an analysis of deidentified retail pharmacy prescription data for 4761 individuals. METHODS: Data were first assessed for DDIs, and individuals were stratified to a risk category using the logic of a commercially available digital DDGI tool. To calculate the frequency of potential DGIs and DDGIs, genotypes were imputed and randomly allocated to the cohort 100 times via Monte Carlo simulation according to each variant's frequency in the general population. RESULTS: The probability of a DDI of any impact was 26.0% and increased to 49.6% (95% CI, 48.4%-50.7%) when drug-metabolizing phenotypes were ascribed according to the distribution of variants of 11 genes as found in a Caucasian population. There was a 7.8% probability of major DDIs, which increased to a 10.1% (95% CI, 9.5%-10.8%) probability with the addition of genetic contributions. The probability of DDGIs of any impact was correlated with the number of medications. Antidepressants, antiemetics, blood products and modifiers, analgesics, and antipsychotics had the highest probability of DDGIs. CONCLUSIONS: The probability of drug interaction risk increased when phenotypes associated with genetic polymorphisms were attributed to the population. These data suggest that pharmacogenomic assessment may be useful in predicting drug interactions and severity when evaluating patient medication profiles.


Asunto(s)
Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Farmacias , Humanos , Interacciones Farmacológicas , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/genética , Genotipo
10.
Artículo en Inglés | MEDLINE | ID: mdl-36429715

RESUMEN

Tuberculosis (TB) is the tenth leading cause of death worldwide. About 1.3 million people die from TB each year, and most of them are in developing countries. The stigma associated with TB is a barrier to seeking treatment and adequate care. It causes a delay in treatment-seeking and diagnosis and thus decreases the likelihood of being cured and ultimately leads to death. The objective of this study was to explore the perceptions, attitudes, experiences, and opinions about stigma related to TB among adults infected with TB and adults who were not infected with TB. Our study was qualitative in nature. The study was conducted in the community of Bolgatanga municipality of the upper-east region of Ghana. Three focus group discussions (FGDs) were conducted; one with six TB-infected females, one with seven TB-infected males, and one with six non-TB-infected participants. Data were analyzed using qualitative content analysis and presented in pre-defined and/or emerging themes: perception about signs and symptoms observed by TB infected person, attitudes towards TB patients before and after diagnosis, reasons for stigmatization, perception about diagnostic testing, and taking the drugs. Transcripts of the discussions were read, and a list of meanings for units, codes, and themes was generated on the research question. We identified the existence of stigma associated with TB. TB-infected male patients had more autonomy in decision-making about receiving treatment and other family matters compared to female TB patients. TB-infected women suffered more economic vulnerability due to the loss of their work, and the stigma was worsened due to delayed diagnosis and treatment, and they were regarded as liabilities rather than assets. TB-infected patients became stigmatized because non-TB-infected community participants did not want to come into close contact with them. Our findings suggest heightening of advocacy, communication, social mobilization, and health education on TB in the community of Bolgatanga municipality is needed to allay TB-related stigma, especially for women.


Asunto(s)
Estigma Social , Tuberculosis , Adulto , Humanos , Femenino , Masculino , Ghana/epidemiología , Tuberculosis/tratamiento farmacológico , Investigación Cualitativa , Estereotipo
11.
Mol Biol Evol ; 39(10)2022 10 07.
Artículo en Inglés | MEDLINE | ID: mdl-36134526

RESUMEN

The amplification and diversification of genes into large multi-gene families often mark key evolutionary innovations, but this process often creates genetic redundancy that hinders functional investigations. When the model budding yeast Saccharomyces cerevisiae transitions to anaerobic growth conditions, the cell massively induces the expression of seven serine/threonine-rich anaerobically-induced cell wall mannoproteins (anCWMPs): TIP1, TIR1, TIR2, TIR3, TIR4, DAN1, and DAN4. Here, we show that these genes likely derive evolutionarily from a single ancestral anCWMP locus, which was duplicated and translocated to new genomic contexts several times both prior to and following the budding yeast whole genome duplication (WGD) event. Based on synteny and their phylogeny, we separate the anCWMPs into four gene subfamilies. To resolve prior inconclusive genetic investigations of these genes, we constructed a set of combinatorial deletion mutants to determine their contributions toward anaerobic growth in S. cerevisiae. We found that two genes, TIR1 and TIR3, were together necessary and sufficient for the anCWMP contribution to anaerobic growth. Overexpressing either gene alone was insufficient for anaerobic growth, implying that they encode non-overlapping functional roles in the cell during anaerobic growth. We infer from the phylogeny of the anCWMP genes that these two important genes derive from an ancient duplication that predates the WGD event, whereas the TIR1 subfamily experienced gene family amplification after the WGD event. Taken together, the genetic and molecular evidence suggests that one key anCWMP gene duplication event, several auxiliary gene duplication events, and functional divergence underpin the evolution of anaerobic growth in budding yeasts.


Asunto(s)
Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Anaerobiosis , Proteínas Portadoras/genética , Evolución Molecular , Duplicación de Gen , Glicoproteínas/genética , Filogenia , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Serina/genética , Treonina/genética
12.
J Allied Health ; 51(2): 136-142, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35640293

RESUMEN

PURPOSE: We examined lexical sophistication of written personal statements from physical therapy applicants to determine whether recurrence quantification analysis (RQA) indices distinguish higher- versus lower-scored candidates and correlate with other admissions variables. METHODS: Written personal statements were extracted from 152 applications, coded numerically, and analyzed with RQA. Along with other RQA indices, determinism-representing predictability of words and phrases-was quantified. A receiver operating characteristic (ROC) curve analysis was used to examine discriminative validity of RQA indices to distinguish between top-10 and bottom-10 candidates. Correlation coefficients between RQA indices and other admissions variables (grade point averages, standardized exam, behavioral interview, and cumulative admissions scores) were also examined. RESULTS: Determinism in personal statements was lower in top-scored (mean 7.38%) than bottom-scored candidates (mean 11.29%, p = 0.015), differentiated between them with 70% sensitivity (95% CI 34.8%-93.3%) and 100% specificity (95% CI 69.2%-100%), and correlated negatively with candidates' behavioral interview scores (r = -0.168, p = 0.039). DISCUSSION: The greater expressive lexical sophistication characterized by lower determinism in personal statements provides information about candidates' writing proficiency as a component of their communication abilities that may not otherwise be assessed in traditional admissions variables.


Asunto(s)
Criterios de Admisión Escolar , Escritura , Estudios Transversales , Humanos , Modalidades de Fisioterapia
13.
Pharmacogenomics ; 23(5): 327-333, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35296147

RESUMEN

The emerging discipline of pharmacogenetics (PGx) has the goal of aiding the selection of effective therapies and personalized dosing, decreasing the likelihood of adverse drug reactions and optimizing resource utilization. Simultaneously, the rapid evolution of economically feasible genetic testing technologies has resulted in a raft of commercial entities that provide genetic data to providers for use with their complex patients. The adoption of pharmacogenomics in psychiatry is growing, but it is limited by several factors, including the limitless permutations of drugs, comorbid conditions and concomitant medications and provider understanding of phenomena such as phenoconversion. We established an expert PGx consultation service for psychiatric providers who utilize our commercial PGx assay. To date, this service has provided ∼16,000 consults with extremely high levels of satisfaction; in an anonymous survey, 96% of respondents reported a rating of "very helpful" or "extremely helpful".


Asunto(s)
Pruebas de Farmacogenómica , Psiquiatría , Humanos , Farmacogenética/métodos , Derivación y Consulta
14.
Clin J Sport Med ; 32(3): e313-e315, 2022 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-34009786

RESUMEN

OBJECTIVE: To compare the validity indices of the King-Devick (KD) test in hockey players using any increase in test time over baseline to a 6-second increase as a positive concussion test. We hypothesized the KD test using the 6-second change would yield greater validity indices. DESIGN: Prospective observational cohort study. SETTING: Sports complex. PARTICIPANTS: Sixty-five male hockey players aged 13 to 20 years. INDEPENDENT VARIABLE: Concussion diagnosis. MAIN OUTCOME MEASURES: Time to complete the KD test. Sensitivity (SN), specificity (SP), and the positive likelihood ratios (LRs+) were calculated using 2 thresholds for a positive test: (1) any increase in time and (2) an increase of 6 seconds or greater. RESULTS: Eighteen players (27.7%) were diagnosed with a concussion. Using any increase in time as a positive test yielded the following: SN 72.2%, SP 78.7%, LR+ 3.4, and LR- 0.4. Using the 6-second threshold yielded the following: SN 44.4%, SP 93.6%, LR+ 7.0, and LR- 0.6. A receiver operator curve analysis confirmed 6.40 seconds or greater maximized the LR+. CONCLUSIONS: A 6-second or greater increase in the KD test performance provides greater validity in diagnosing concussion as compared with any increase in performance time.


Asunto(s)
Conmoción Encefálica , Hockey , Conmoción Encefálica/diagnóstico , Humanos , Masculino , Pruebas Neuropsicológicas , Estudios Prospectivos
15.
J Mamm Evol ; 28(4): 1083-1143, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34924738

RESUMEN

Taeniolabis taoensis is an iconic multituberculate mammal of early Paleocene (Puercan 3) age from the Western Interior of North America. Here we report the discovery of significant new skull material (one nearly complete cranium, two partial crania, one nearly complete dentary) of T. taoensis in phosphatic concretions from the Corral Bluffs study area, Denver Formation (Danian portion), Denver Basin, Colorado. The new skull material provides the first record of the species from the Denver Basin, where the lowest in situ specimen occurs in river channel deposits ~730,000 years after the Cretaceous-Paleogene boundary, roughly coincident with the first appearance of legumes in the basin. The new material, in combination with several previously described and undescribed specimens from the Nacimiento Formation of the San Juan Basin, New Mexico, is the subject of detailed anatomical study, aided by micro-computed tomography. Our analyses reveal many previously unknown aspects of skull anatomy. Several regions (e.g., anterior portions of premaxilla, orbit, cranial roof, occiput) preserved in the Corral Bluffs specimens allow considerable revision of previous reconstructions of the external cranial morphology of T. taoensis. Similarly, anatomical details of the ascending process of the dentary are altered in light of the new material. Although details of internal cranial anatomy (e.g., nasal and endocranial cavities) are difficult to discern in the available specimens, we provide, based on UCMP 98083 and DMNH.EPV 95284, the best evidence to date for inner ear structure in a taeniolabidoid multituberculate. The cochlear canal of T. taoensis is elongate and gently curved and the vestibule is enlarged, although to a lesser degree than in Lambdopsalis.

16.
Opt Express ; 29(23): 37602-37616, 2021 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-34808829

RESUMEN

Wavefront shaping with spatial light modulators (SLMs) enables aberration correction, especially for light control through complex media, like biological tissues and multimode fibres. High-fidelity light field shaping is associated with the calculation of computer generated holograms (CGHs), of which there are a variety of algorithms. The achievable performance of CGH algorithms depends on various parameters. In this paper, four different algorithms for CGHs are presented and compared for complex light field generation. Two iterative, double constraint Gerchberg-Saxton and direct search, and the two analytical, superpixel and phase encoding, algorithms are investigated. For each algorithm, a parameter study is performed varying the modulator's pixel number and phase resolution. The analysis refers to mode field generation in multimode fibre endoscopes and communication. This enables generality by generating specific mode combinations according to certain spatial frequency power spectra. Thus, the algorithms are compared varying spatial frequencies applied to different implementation scenarios. Our results demonstrate that the choice of algorithms has a significant impact on the achievable performance. This comprehensive study provides the required guide for CGH algorithm selection, improving holographic systems towards multimode fibre endoscopy and communications.

17.
Metab Eng ; 68: 119-130, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34592433

RESUMEN

Bottlenecks in the efficient conversion of xylose into cost-effective biofuels have limited the widespread use of plant lignocellulose as a renewable feedstock. The yeast Saccharomyces cerevisiae ferments glucose into ethanol with such high metabolic flux that it ferments high concentrations of glucose aerobically, a trait called the Crabtree/Warburg Effect. In contrast to glucose, most engineered S. cerevisiae strains do not ferment xylose at economically viable rates and yields, and they require respiration to achieve sufficient xylose metabolic flux and energy return for growth aerobically. Here, we evolved respiration-deficient S. cerevisiae strains that can grow on and ferment xylose to ethanol aerobically, a trait analogous to the Crabtree/Warburg Effect for glucose. Through genome sequence comparisons and directed engineering, we determined that duplications of genes encoding engineered xylose metabolism enzymes, as well as TKL1, a gene encoding a transketolase in the pentose phosphate pathway, were the causative genetic changes for the evolved phenotype. Reengineered duplications of these enzymes, in combination with deletion mutations in HOG1, ISU1, GRE3, and IRA2, increased the rates of aerobic and anaerobic xylose fermentation. Importantly, we found that these genetic modifications function in another genetic background and increase the rate and yield of xylose-to-ethanol conversion in industrially relevant switchgrass hydrolysate, indicating that these specific genetic modifications may enable the sustainable production of industrial biofuels from yeast. We propose a model for how key regulatory mutations prime yeast for aerobic xylose fermentation by lowering the threshold for overflow metabolism, allowing mutations to increase xylose flux and to redirect it into fermentation products.


Asunto(s)
Proteínas de Saccharomyces cerevisiae , Xilosa , Biocombustibles , Fermentación , Glucosa , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
18.
R Soc Open Sci ; 8(5): 210098, 2021 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-34035950

RESUMEN

The Maevarano Formation in northwestern Madagascar has yielded a series of exceptional fossils over the course of the last three decades that provide important insights into the evolution of insular ecosystems during the latest Cretaceous (Maastrichtian). We here describe a new genus and species of pelomedusoid turtle from this formation, Sahonachelys mailakavava, based on a nearly complete skeleton. A phylogenetic analysis suggests close affinities of Sahonachelys mailakavava with the coeval Madagascan Sokatra antitra. These two taxa are the only known representatives of the newly recognized clade Sahonachelyidae, which is sister to the speciose clade formed by Bothremydidae and Podocnemidoidae. A close relationship with coeval Indian turtles of the clade Kurmademydini is notably absent. A functional assessment suggests that Sahonachelys mailakavava was a specialized suction feeder that preyed upon small-bodied invertebrates and vertebrates. This is a unique feeding strategy among crown pelomedusoids that is convergent upon that documented in numerous other clades of turtles and that highlights the distinct evolutionary pathways taken by Madagascan vertebrates.

19.
Mil Med ; 186(Suppl 1): 833-838, 2021 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-33499520

RESUMEN

INTRODUCTION: The U.S. Navy Medicine has a long history of conducting global health missions that foster international diplomacy through medical knowledge exchange with a goal of increasing partner nation's health care capacity. Pacific Partnership is an annual U.S. Navy-sponsored joint operation that enhances medical collaboration with participating nations throughout the Indo-Asia-Pacific region. Since 2015, a U.S. Navy Cardiology team has conducted a structural heart disease interventional workshop focused on congenital heart disease with the cardiologists at the Da Nang General Hospital, Da Nang, Vietnam. Herein, we describe the multinational collaborative project including the patient registry we developed to monitor the short- and long-term outcomes of structural heart disease interventions preformed during Pacific Partnership 2015 and 2016. MATERIALS AND METHODS: Our team developed a sustainable procedural registry with the goal of following the long-term outcomes of cardiac interventions for congenital heart disease in Vietnamese patients. Specifically, the registry was designed to record the changes in symptoms referable to the cardiovascular system and for device placement-associated complications for devices placed in 2015 and 2016 and has been updated annually thereafter. RESULTS: Twelve patients (age range, 7 months to 31 years) underwent successful atrial septal defect closure in 2015 without procedural complications. The follow-up rate was 75% at 1 year and 67% at 2 years, and all devices were in appropriate position with no complications identified. Fifteen patients (age range, 20-66 years) underwent successful atrial septal defect closure in 2016. The follow-up rate was 62.5% at 1 year, and all devices were in appropriate position with no complications identified. Three patients (age range, 5-25 months) underwent successful device closure of the patent ductus arteriosus in 2015 without complications. The follow-up rate was 67% in 2016 and again in 2017. Six patients (age range, 9-74 years) underwent successful patent ductus arteriosus closure in 2016 without complications. The follow-up rate was 67% in 2017, and all devices were in appropriate position with no device-related complications identified. CONCLUSIONS: The development of a patient registry during these missions allowed for the longitudinal monitoring of outcomes for cardiac interventions. Notably, treated patients experienced symptomatic improvement without significant long-term procedural complications. Following patients longitudinally across medical missions is of recognized importance but remains a difficult objective to achieve for a multitude of factors including administrative and financial burdens on both the medical systems and the patients of host nations. Despite these limitations, longitudinal follow-up of patient care facilitated by a patient registry has a vital role in monitoring the quality of care provided and should be an integral part of all future global medical missions.


Asunto(s)
Cardiología , Conducto Arterioso Permeable , Adolescente , Adulto , Anciano , Cateterismo Cardíaco , Niño , Preescolar , Ecocardiografía , Estudios de Seguimiento , Defectos del Tabique Interatrial/cirugía , Humanos , Persona de Mediana Edad , Resultado del Tratamiento , Vietnam , Adulto Joven
20.
Clin J Sport Med ; 31(3): e150-e160, 2021 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-31842055

RESUMEN

OBJECTIVES: The Ice Hockey Summit III provided updated scientific evidence on concussions in hockey to inform these 5 objectives: (1) describe sport related concussion (SRC) epidemiology; (2) classify prevention strategies; (3) define objective, diagnostic tests; (4) identify treatment; and (5) integrate science and clinical care into prioritized action plans and policy. METHODS: Our action plan evolved from 40 scientific presentations. The 155 attendees (physicians, athletic trainers, physical therapists, nurses, neuropsychologists, scientists, engineers, coaches, and officials) voted to prioritize these action items in the final Summit session. RESULTS: To (1) establish a national and international hockey database for SRCs at all levels; (2) eliminate body checking in Bantam youth hockey games; (3) expand a behavior modification program (Fair Play) to all youth hockey levels; (4) enforce game ejection penalties for fighting in Junior A and professional hockey leagues; (5) establish objective tests to diagnose concussion at point of care; and (6) mandate baseline testing to improve concussion diagnosis for all age groups. CONCLUSIONS: Expedient implementation of the Summit III prioritized action items is necessary to reduce the risk, severity, and consequences of concussion in the sport of ice hockey.


Asunto(s)
Traumatismos en Atletas , Conmoción Encefálica , Hockey , Traumatismos en Atletas/diagnóstico , Traumatismos en Atletas/epidemiología , Traumatismos en Atletas/prevención & control , Conmoción Encefálica/diagnóstico , Conmoción Encefálica/epidemiología , Conmoción Encefálica/prevención & control , Congresos como Asunto , Hockey/lesiones , Humanos , Incidencia
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