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1.
Nat Commun ; 15(1): 5457, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38951524

RESUMEN

The impact of ocean warming on fish and fisheries is vigorously debated. Leading theories project limited adaptive capacity of tropical fishes and 14-39% size reductions by 2050 due to mass-scaling limitations of oxygen supply in larger individuals. Using the world's hottest coral reefs in the Persian/Arabian Gulf as a natural laboratory for ocean warming - where species have survived >35.0 °C summer temperatures for over 6000 years and are 14-40% smaller at maximum size compared to cooler locations - we identified two adaptive pathways that enhance survival at elevated temperatures across 10 metabolic and swimming performance metrics. Comparing Lutjanus ehrenbergii and Scolopsis ghanam from reefs both inside and outside the Persian/Arabian Gulf across temperatures of 27.0 °C, 31.5 °C and 35.5 °C, we reveal that these species show a lower-than-expected rise in basal metabolic demands and a right-shifted thermal window, which aids in maintaining oxygen supply and aerobic performance to 35.5 °C. Importantly, our findings challenge traditional oxygen-limitation theories, suggesting a mismatch in energy acquisition and demand as the primary driver of size reductions. Our data support a modified resource-acquisition theory to explain how ocean warming leads to species-specific size reductions and why smaller individuals are evolutionarily favored under elevated temperatures.


Asunto(s)
Arrecifes de Coral , Animales , Tamaño Corporal/fisiología , Calentamiento Global , Océanos y Mares , Peces/fisiología , Océano Índico , Oxígeno/metabolismo , Temperatura , Calor , Explotaciones Pesqueras
3.
Arch Rehabil Res Clin Transl ; 6(2): 100332, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-39006115

RESUMEN

Objective: To describe the outcomes (change in functional independence and discharge disposition) of patients who after liver transplantation received acute inpatient rehabilitation in a freestanding rehabilitation hospital. Design: A retrospective chart review was conducted of patients admitted to an acute inpatient rehabilitation hospital within 6 months of undergoing liver transplantation between January 2014 and December 2018. Change in function from rehabilitation admission to discharge was measured using FIM Change and FIM Efficiency. Setting: A freestanding rehabilitation hospital. Participants: 107 patients who underwent acute inpatient rehabilitation at a freestanding rehabilitation hospital within 6 months after liver transplantation who met inclusion criteria (N=107). Most were men (71.96%), and the mean age of the patient population was 62.15 years. Interventions: Acute inpatient rehabilitation consisting of at least 3 hours of therapy 5 days a week split between physical therapy, occupational therapy, and speech language pathology services. Main Outcome Measure: FIM Change, FIM Efficiency, Discharge Disposition. Results: Participants were found to have statistically significant positive FIM Change (P<.00001) and FIM Efficiency (P<.00001). The mean FIM Change and Efficiency were 35.7±11.8 and 2.4±1.0, respectively. 83.2% (n = 89) were ultimately discharged to the community. Conclusion: Acute inpatient rehabilitation provides patients who have received a liver transplant with the opportunity to measurably improve their function and independence, with most patients being able to return home.

4.
J Med Chem ; 67(14): 12261-12313, 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-38959455

RESUMEN

The pyrazolo[1,5-a]pyrimidine scaffold is a promising scaffold to develop potent and selective CSNK2 inhibitors with antiviral activity against ß-coronaviruses. Herein, we describe the discovery of a 1,2,4-triazole group to substitute a key amide group for CSNK2 binding present in many potent pyrazolo[1,5-a]pyrimidine inhibitors. Crystallographic evidence demonstrates that the 1,2,4-triazole replaces the amide in forming key hydrogen bonds with Lys68 and a water molecule buried in the ATP-binding pocket. This isosteric replacement improves potency and metabolic stability at a cost of solubility. Optimization for potency, solubility, and metabolic stability led to the discovery of the potent and selective CSNK2 inhibitor 53. Despite excellent in vitro metabolic stability, rapid decline in plasma concentration of 53 in vivo was observed and may be attributed to lung accumulation, although in vivo pharmacological effect was not observed. Further optimization of this novel chemotype may validate CSNK2 as an antiviral target in vivo.


Asunto(s)
Antivirales , Quinasa de la Caseína II , Pirimidinas , Triazoles , Replicación Viral , Triazoles/farmacología , Triazoles/química , Triazoles/síntesis química , Pirimidinas/farmacología , Pirimidinas/química , Pirimidinas/síntesis química , Antivirales/farmacología , Antivirales/química , Antivirales/síntesis química , Animales , Humanos , Replicación Viral/efectos de los fármacos , Quinasa de la Caseína II/antagonistas & inhibidores , Quinasa de la Caseína II/metabolismo , Pirazoles/farmacología , Pirazoles/química , Pirazoles/síntesis química , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/síntesis química , Amidas/química , Amidas/farmacología , Amidas/síntesis química , Relación Estructura-Actividad , Ratones , Ratas , SARS-CoV-2/efectos de los fármacos , Descubrimiento de Drogas , Masculino
5.
Arthritis Rheumatol ; 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-39039899

RESUMEN

OBJECTIVES: To develop and validate classification criteria for axial disease in youth with juvenile spondyloarthritis (SpA; AxJSpA). METHODS: This international initiative consisted of four phases: 1) Item generation; 2) Item reduction; 3) Criteria development; and 4) Validation of the AxJSpA criteria by an independent team of experts in an internationally representative Validation cohort. RESULTS: These criteria are intended to be used on youth with a physician diagnosis of juvenile SpA and for whom axial disease is suspected. Item generation consisted of a systematic literature review and a free-listing exercise using input from international physicians and collectively resulted in 108 items. After the item reduction exercise and expert panel input, 37 items remained for further consideration. The final AxJSpA criteria domains included: imaging: active inflammation, imaging: structural lesions, pain chronicity, pain pattern, pain location, stiffness, and genetics. The most heavily weighted domains were active inflammation and structural lesions on imaging. Imaging typical of sacroiliitis was deemed necessary, but not sufficient, to classify a youth with AxJSpA. The threshold for classification of AxJSpA was a score of ≥55 (out of 100). When tested in the validation data set, the final criteria had a specificity of 97.5% (95% CI: 91.4-99.7), sensitivity of 64.3% (95% CI: 54.9-73.1) and Area Under the Receiver Operating Characteristic (AUROC) curve of 0.81 (95% CI: 0.76-0.86). CONCLUSIONS: The new AxJSpA classification criteria require an entry criterion, physician diagnosis of juvenile SpA, and include seven weighted domains. The AxJSpA classification criteria are validated and designed to identify participants for research studies.

6.
Nature ; 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39009005

RESUMEN

Transmission spectroscopy has been a workhorse technique over the past two decades to constrain the physical and chemical properties of exoplanet atmospheres 1-5. One of its classical key assumptions is that the portion of the atmosphere it probes - the terminator region - is homogeneous. Several works in the past decade, however, have put this into question for highly irradiated, hot (Teq ≳ 1000 K) gas giant exoplanets both empirically 6-10 and via 3-dimensional modelling 11-17. While models predict clear differences between the evening (day-to-night) and morning (night-to-day) terminators, direct morning/evening transmission spectra in a wide wavelength range has not been reported for an exoplanet to date. Under the assumption of precise and accurate orbital parameters on WASP-39 b, here we report the detection of inhomogeneous terminators on the exoplanet WASP-39 b, which allows us to retrieve its morning and evening transmission spectra in the near-infrared (2 - 5 µm) using JWST. We observe larger transit depths in the evening which are, on average, 405±88 ppm larger than the morning ones, also having qualitatively larger features than the morning spectrum. The spectra are best explained by models in which the evening terminator is hotter than the morning terminator by 177 - 57 + 65 K with both terminators having C/O ratios consistent with solar. General circulation models (GCMs) predict temperature differences broadly consistent with the above value and point towards a cloudy morning terminator and a clearer evening terminator.

7.
PLoS One ; 19(6): e0305539, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38885214

RESUMEN

The human forearm model is commonly employed in physiological investigations exploring local vascular function and oxygen delivery; however, the effect of arm dominance on exercising forearm hemodynamics and skeletal muscle oxygen saturation (SmO2) in untrained individuals is poorly understood. Therefore, the purpose of this study was to explore the effect of self-identified arm dominance on forearm hemodynamics and SmO2 in untrained individuals during submaximal, non-ischemic forearm exercise. Twenty healthy individuals (23±4 years, 50% female; 80% right-handed) completed three-minute bouts of supine rhythmic (1 second contraction: 2 second relaxation duty cycle) forearm handgrip exercise at both absolute (10kg; 98N) and relative (30% of maximal voluntary contraction) intensities in each forearm. Beat-by-beat measures of forearm blood flow (FBF; ml/min), mean arterial blood pressure (MAP; mmHg) and flexor digitorum superficialis SmO2 (%) were obtained throughout and averaged during the final 30 seconds of rest, exercise, and recovery while forearm vascular conductance was calculated (FVC; ml/min/100mmHg). Data are Δ from rest (mean±SD). Absolute force production did not differ between non-dominant and dominant arms (97±11 vs. 98±13 N, p = 0.606) whereas relative force production in females did (69±24 vs. 82±25 N, p = 0.001). At both exercise intensities, FBFRELAX, FVCRELAX, MAPRELAX, and the time constant tau for FBF and SmO2 were unaffected by arm dominance (all p>0.05). While arm dominance did not influence SmO2 during absolute intensity exercise (p = 0.506), the non-dominant arm in females experienced an attenuated reduction in SmO2 during relative intensity exercise (-14±10 vs. -19±8%, p = 0.026)-though exercise intensity was also reduced (p = 0.001). The present investigation has demonstrated that arm dominance in untrained individuals does not impact forearm hemodynamics or SmO2 during handgrip exercise.


Asunto(s)
Ejercicio Físico , Antebrazo , Hemodinámica , Músculo Esquelético , Humanos , Femenino , Músculo Esquelético/fisiología , Músculo Esquelético/irrigación sanguínea , Antebrazo/irrigación sanguínea , Antebrazo/fisiología , Hemodinámica/fisiología , Masculino , Ejercicio Físico/fisiología , Adulto , Adulto Joven , Fuerza de la Mano/fisiología , Brazo/fisiología , Brazo/irrigación sanguínea , Flujo Sanguíneo Regional/fisiología , Oxígeno/metabolismo , Consumo de Oxígeno/fisiología
8.
J Funct Morphol Kinesiol ; 9(2)2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38921634

RESUMEN

The strength of the shoulder musculature involved with internal rotation and arm extension plays an important role in the overhead throwing motion for baseball athletes, both for throwing-related performance and injury risk. The maintenance of shoulder strength is a high priority for baseball athletes throughout a season; however, little is known in regards to the expected changes in strength throughout a season. To examine pre-post changes in shoulder strength, lower body power, and body composition among collegiate baseball players after the completion of a summer baseball league season. Amateur baseball players (n = 12; age: 20.9 ± 1.0 years.; height: 181.6 ± 5.6 cm; body mass: 86.4 ± 11.1 kg; BMI: 26.0 ± 2.6 kg/m2) participated in the current study. Pre- and post-competitive season, the participants completed shoulder strength assessments and body composition and countermovement vertical jump (CMJ) tests. An upper-body isometric test (athletic shoulder [ASH] test) was used to evaluate shoulder strength for each arm. Each subject completed maximal isometric contractions for both the throwing and non-throwing arms at four separate angles of abduction (180°, 'I'; 135°, 'Y'; 90°, 'T'; and -180°, 'A') while lying in a prone position. For shoulder strength, the primary dependent variable of interest was a composite measure that represented the average of the forces produced across all four positions of the ASH test (I, Y, T, A). For the ASH test composite measure, there was a trend toward a significant arm-by-time interaction effect (p = 0.08), as shoulder strength decreased by 9.03% for the throwing arm (ES = 0.72; 95% CI = [-0.27, -0.01]), compared to only 2.03% for the non-throwing arm (ES = 0.15; 95% CI = [-0.16, 0.09]), over the course of the season. The main effects of time (p = 0.16) and arm (p = 0.58) were not significant for the ASH test composite measure. There was no relationship between lower body power and throwing arm strength at baseline (r = 0.20, p = 0.56), and only a non-significant weak relationship at post-test (r = 0.28, p = 0.41). Throughout a season, baseball players may experience reductions in shoulder strength of the throwing arm with minimal changes in shoulder strength in the non-throwing arm.

9.
Eur Respir J ; 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38936967

RESUMEN

A diagnosis of chronic obstructive pulmonary disease (COPD) is mainly considered in individuals with more than 10 pack-years of smoking. We tested the hypothesis that low smoking exposure, below the critical threshold of 10 pack-years, increases risk of COPD and leads to poor prognosis.We followed non-obstructive adult smokers from the Copenhagen City Heart Study for COPD, defined as forced expiratory volume in one second [FEV1]/forced vital capacity [FVC]<0.70 and FEV1<80% predicted, and for related clinical outcomes. First, we followed individuals for 5years according to baseline smoking for risk of developing COPD, and hereafter for up to four decades for severe exacerbations and death.In 6098 non-obstructive smokers, 1781(29%) developed COPD after 5 years follow-up; 23% in individuals with <10pack-years of smoking at baseline, 26% in those with 10-19.9pack-years, 30% in those with 20-39.9pack-years, and 39% in those with ≥40pack-years. During four decades follow-up, we recorded 620 exacerbations and 5573 deaths. Compared to individuals without COPD with <10pack-years of smoking, multivariable adjusted hazard ratios (HRs) for exacerbations were 1.94(95% confidence interval:1.36-2.77) in those without COPD with ≥10pack-years, 2.83(1.72-4.66) in those with COPD with <10pack-years, 4.34(2.93-6.43) in COPD with 10-19.9pack-years, 4.39(2.98-6.47) in COPD with 20-39.9pack-years, and 4.98(3.11-7.97) in COPD with ≥40pack-years. Corresponding HRs for all-cause mortality were 1.20(1.10-1.32), 1.33(1.14-1.56), 1.59(1.40-1.80),1.81(1.62-2.03), and 1.81(1.55-2.10), respectively.Low smoking exposure below the critical threshold of 10 pack-years increases risk of COPD in middle-aged adults within 5 years, and these individuals have increased risk of severe exacerbation and early death over four decades.

10.
bioRxiv ; 2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38915605

RESUMEN

Spleen tyrosine kinase (SYK) is a non-receptor tyrosine kinase that is activated by phosphorylation events downstream of FcR, B-cell and T-cell receptors, integrins, and C-type lectin receptors. When the tandem Src homology 2 (SH2) domains of SYK bind to phosphorylated immunoreceptor tyrosine-based activation motifs (pITAMs) contained within these immunoreceptors, or when SYK is phosphorylated in interdomain regions A and B, SYK is activated. SYK gain-of-function (GoF) variants were previously identified in six patients that had higher levels of phosphorylated SYK and phosphorylated downstream proteins JNK and ERK. Furthermore, the increased SYK activation resulted in the clinical manifestation of immune dysregulation, organ inflammation, and a predisposition for lymphoma. The knowledge that the SYK GoF variants have enhanced activity was leveraged to develop a SYK NanoBRET cellular target engagement assay in intact live cells with constructs for the SYK GoF variants. Herein, we developed a potent SYK-targeted NanoBRET tracer using a SYK donated chemical probe, MRL-SYKi, that enabled a NanoBRET cellular target engagement assay for SYK GoF variants, SYK(S550Y), SYK(S550F), and SYK(P342T). We determined that ATP-competitive SYK inhibitors bind potently to these SYK variants in intact live cells. Additionally, we demonstrated that MRL-SYKi can effectively reduce the catalytic activity of SYK variants, and the phosphorylation levels of SYK(S550Y) in an epithelial cell line (SW480) stably expressing SYK(S550Y).

11.
JAMA Cardiol ; 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38865108

RESUMEN

Importance: Blood pressure response during acute exercise (exercise blood pressure [EBP]) is associated with the future risk of hypertension and cardiovascular disease (CVD). Biochemical characterization of EBP could inform disease biology and identify novel biomarkers of future hypertension. Objective: To identify protein markers associated with EBP and test their association with incident hypertension. Design, Setting, and Participants: This study assayed 4977 plasma proteins in 681 healthy participants (from 763 assessed) of the Health, Risk Factors, Exercise Training and Genetics (HERITAGE; data collection from January 1993 to December 1997 and plasma proteomics from January 2019 to January 2020) Family Study at rest who underwent 2 cardiopulmonary exercise tests. Individuals were free of CVD at the time of recruitment. Individuals with resting SBP ≥160 mm Hg or DBP ≥100 mm Hg or taking antihypertensive drug therapy were excluded from the study. The association between resting plasma protein levels to both resting BP and EBP was evaluated. Proteins associated with EBP were analyzed for their association with incident hypertension in the Framingham Heart Study (FHS; n = 1177) and validated in the Jackson Heart Study (JHS; n = 772) and Multi-Ethnic Study of Atherosclerosis (MESA; n = 1367). Proteins associated with incident hypertension were tested for putative causal links in approximately 700 000 individuals using cis-protein quantitative loci mendelian randomization (cis-MR). Data were analyzed from January 2023 to January 2024. Exposures: Plasma proteins. Main Outcomes and Measures: EBP was defined as the BP response during a fixed workload (50 W) on a cycle ergometer. Hypertension was defined as BP ≥140/90 mm Hg or taking antihypertensive medication. Results: Among the 681 participants in the HERITAGE Family Study, the mean (SD) age was 34 (13) years; 366 participants (54%) were female; 238 (35%) were self-reported Black and 443 (65%) were self-reported White. Proteomic profiling of EBP revealed 34 proteins that would not have otherwise been identified through profiling of resting BP alone. Transforming growth factor ß receptor 3 (TGFBR3) and prostaglandin D2 synthase (PTGDS) had the strongest association with exercise systolic BP (SBP) and diastolic BP (DBP), respectively (TGFBR3: exercise SBP, ß estimate, -3.39; 95% CI, -4.79 to -2.00; P = 2.33 × 10-6; PTGDS: exercise DBP ß estimate, -2.50; 95% CI, -3.29 to -1.70; P = 1.18 × 10-9). In fully adjusted models, TGFBR3 was inversely associated with incident hypertension in FHS, JHS, and MESA (hazard ratio [HR]: FHS, 0.86; 95% CI, 0.75-0.97; P = .01; JHS, 0.87; 95% CI, 0.77-0.97; P = .02; MESA, 0.84; 95% CI, 0.71-0.98; P = .03; pooled cohort, 0.86; 95% CI, 0.79-0.92; P = 6 × 10-5). Using cis-MR, genetically predicted levels of TGFBR3 were associated with SBP, hypertension, and CVD events (SBP: ß, -0.38; 95% CI, -0.64 to -0.11; P = .006; hypertension: odds ratio [OR], 0.99; 95% CI, 0.98-0.99; P < .001; heart failure with hypertension: OR, 0.86; 95% CI, 0.77-0.97; P = .01; CVD: OR, 0.84; 95% CI, 0.77-0.92; P = 8 × 10-5; cerebrovascular events: OR, 0.77; 95% CI, 0.70-0.85; P = 5 × 10-7). Conclusions and Relevance: Plasma proteomic profiling of EBP identified a novel protein, TGFBR3, which may protect against elevated BP and long-term CVD outcomes.

12.
Cureus ; 16(5): e60413, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38883037

RESUMEN

Diabetic foot ulcers represent a significant complication of diabetes mellitus, characterized by mechanical changes of bony architecture often leading to chronic wounds with increased risk of infection and impaired healing. Morganella morganii, a Gram-negative bacterium, is one of the pathogens found in infected diabetic foot ulcers. It is a human gastrointestinal commensal organism that may cause widespread deadly infections. This report discusses the case of a 76-year-old male with diabetes mellitus who presented with M. morganii diabetic foot ulcer to an in-patient rehabilitation facility. Despite conventional wound care and antibiotic therapy, the ulcer failed to improve. The management approach for this patient consisted of a rehabilitation modality called Vaporox, a machine that utilizes vaporous hyperoxia therapy (VHT), as it combines ultrasonic mist and high concentration of oxygen to fasten revascularization and healing. This case highlights the potential efficacy of VHT as an adjunctive therapy for the management of diabetic foot ulcers, particularly those complicated by pathogens, such as M. morganii.

13.
Curr Sports Med Rep ; 23(6): 229-236, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38838686

RESUMEN

ABSTRACT: Hip pain is a common concern among athletes. With gluteal tendinopathy, femoroacetabular impingement, and osteoarthritis predominating sports medicine and musculoskeletal practices, less common etiologies may be overlooked. Complex pelvic anatomy and variable pain referral patterns may make identifying an accurate diagnosis challenging. Employing a systematic approach to evaluation and having a thorough understanding of hip region anatomy are essential. A potentially overlooked cause of anterolateral hip pain is iliotibial band origin tendinopathy. Patients often present with pain around the anterolateral hip and tenderness to palpation at the anterolateral iliac crest. While patients with iliotibial band origin tendinopathy usually respond to nonsurgical intervention, there is little literature to guide evaluation and treatment, highlighting a gap in the recognition of this condition. The purpose of this narrative review is to describe the anatomy of the proximal iliotibial band origin, outline the clinical diagnosis and imaging findings of ITBOT, and summarize current treatment options.


Asunto(s)
Tendinopatía , Humanos , Tendinopatía/diagnóstico , Tendinopatía/terapia , Tendinopatía/etiología , Artralgia/etiología , Artralgia/diagnóstico , Articulación de la Cadera , Síndrome de la Banda Iliotibial/diagnóstico , Síndrome de la Banda Iliotibial/terapia , Síndrome de la Banda Iliotibial/etiología
14.
Artículo en Inglés | MEDLINE | ID: mdl-38842227

RESUMEN

BACKGROUND: Penile squamous cell carcinoma (PSCC) carries significant morbidity and mortality. Literature is limited regarding prognostic factors, especially prognostic factors for development of metastasis. OBJECTIVES: To identify independent prognostic factors associated with poor outcomes, defined as local recurrence (LR), metastasis and disease-specific death (DSD) in clinically node-negative PSCC undergoing local therapy. METHODS: Thirty-two-year Retrospective Multicenter Cohort Study of 265 patients with histologically diagnosed PSCC at three tertiary care centres. Predictive models based on patient or tumour characteristics were developed. RESULTS: Local recurrence occurred in 56 patients, metastasis in 52 patients and DSD in 40 patients. In multivariable models, the following five factors were independent prognostic factors based on subhazard ratio (SHR): history of balanitis (LR SHR: 2.3; 95% CI 1.2-4.2), poor differentiation (metastasis SHR 1.9; 95% CI 1.0-3.6), invasion into the corpora (metastasis SHR: 3.0; 95% CI 1.5-5.8 and DSD SHR: 4.5; 95% CI 1.7-12.1), perineural invasion (PNI) (metastasis SHR: 2.8; 95% CI 1.4-5.5 and DSD SHR: 3.5; 95% CI, 1.6-7.8) and a history of phimosis (DSD SHR: 2.5; 95% CI 1.2-5.3). The 5-year cumulative incidence of metastasis was higher for tumours with PNI [cumulative incidence function (CIF) = 55%, 95% CI 38-75 vs. CIF 15%, 95% CI 11-22], corporal invasion (CIF: 35%, 95% CI 26-47 vs. 12%, 95% CI 7-19) and poorly differentiated tumours (CIF = 46%, 95% CI 31-64 vs. CIF 15%, 95% CI 11-22). CONCLUSIONS: History of balanitis, history of phimosis, PNI, corporal invasion and poor differentiation are independent risk factors associated with poor outcomes. Since poor differentiation and PNI currently constitute only T1b disease, prognostic staging can likely be improved.

15.
PLoS One ; 19(6): e0303577, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38843233

RESUMEN

Malic Enzyme 1 (ME1) plays an integral role in fatty acid synthesis and cellular energetics through its production of NADPH and pyruvate. As such, it has been identified as a gene of interest in obesity, type 2 diabetes, and an array of epithelial cancers, with most work being performed in vitro. The current standard model for ME1 loss in vivo is the spontaneous Mod-1 null allele, which produces a canonically inactive form of ME1. Herein, we describe two new genetically engineered mouse models exhibiting ME1 loss at dynamic timepoints. Using murine embryonic stem cells and Flp/FRT and Cre/loxP class switch recombination, we established a germline Me1 knockout model (Me1 KO) and an inducible conditional knockout model (Me1 cKO), activated upon tamoxifen treatment in adulthood. Collectively, neither the Me1 KO nor Me1 cKO models exhibited deleterious phenotype under standard laboratory conditions. Knockout of ME1 was validated by immunohistochemistry and genotype confirmed by PCR. Transmission patterns favor Me1 loss in Me1 KO mice when maternally transmitted to male progeny. Hematological examination of these models through complete blood count and serum chemistry panels revealed no discrepancy with their wild-type counterparts. Orthotopic pancreatic tumors in Me1 cKO mice grow similarly to Me1 expressing mice. Similarly, no behavioral phenotype was observed in Me1 cKO mice when aged for 52 weeks. Histological analysis of several tissues revealed no pathological phenotype. These models provide a more modern approach to ME1 knockout in vivo while opening the door for further study into the role of ME1 loss under more biologically relevant, stressful conditions.


Asunto(s)
Malato Deshidrogenasa , Ratones Noqueados , Fenotipo , Animales , Malato Deshidrogenasa/metabolismo , Malato Deshidrogenasa/genética , Masculino , Ratones , Femenino , Células Germinativas/metabolismo , Ratones Endogámicos C57BL
17.
Microbiol Spectr ; : e0074824, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38916327

RESUMEN

Burkholderia pseudomallei (Bpm) is a Gram-negative intracellular pathogen that causes melioidosis in humans, a neglected, underreported, and lethal disease that can reach a fatal outcome in over 50% of the cases. It can produce both acute and chronic infections, the latter being particularly challenging to eliminate because of the intracellular life cycle of the bacteria and its ability to generate a "persister" dormant state. The molecular mechanism that allows the switch between growing and persister phenotypes is not well understood but it is hypothesized to be due at least in part to the participation of toxin-antitoxin (TA) systems. We have previously studied the link between one of those systems (defined as HigBA) with specific expression patterns associated with levofloxacin antibiotic exposure. Through in silico methods, we predicted the presence of another three pairs of genes encoding for additional putative HigBA systems. Therefore, our main goal was to establish which mechanisms are conserved as well as which pathways are specific among different Bpm TA systems from the same family. We hypothesize that the high prevalence, and sometimes even redundancy of these systems in the Bpm chromosomes indicates that they can interact with each other and not function as only individual systems, as it was traditionally thought, and might be playing an undefined role in Bpm lifecycle. Here, we show that both the toxin and the antitoxin of the different systems contribute to bacterial survival and that toxins from the same family can have a cumulative effect under environmental stressful conditions. IMPORTANCE: Toxin-antitoxin (TA) systems play a significant role in bacterial persistence, a phenomenon where bacterial cells enter a dormant or slow-growing state to survive adverse conditions such as nutrient deprivation, antibiotic exposure, or host immune responses. By studying TA systems in Burkholderia pseudomallei, we can gain insights into how this pathogen survives and persists in the host environment, contributing to its virulence and ability to cause melioidosis chronic infections.

18.
bioRxiv ; 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38895429

RESUMEN

Gene gains and losses are a major driver of genome evolution; their precise characterization can provide insights into the origin and diversification of major lineages. Here, we examined gene family evolution of 1,154 genomes from nearly all known species in the medically and technologically important yeast subphylum Saccharomycotina. We found that yeast gene family and genome evolution are distinct from plants, animals, and filamentous ascomycetes and are characterized by small genome sizes and smaller gene numbers but larger gene family sizes. Faster-evolving lineages (FELs) in yeasts experienced significantly higher rates of gene losses-commensurate with a narrowing of metabolic niche breadth-but higher speciation rates than their slower-evolving sister lineages (SELs). Gene families most often lost are those involved in mRNA splicing, carbohydrate metabolism, and cell division and are likely associated with intron loss, metabolic breadth, and non-canonical cell cycle processes. Our results highlight the significant role of gene family contractions in the evolution of yeast metabolism, genome function, and speciation, and suggest that gene family evolutionary trajectories have differed markedly across major eukaryotic lineages.

19.
JAMA Netw Open ; 7(6): e2417625, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38888920

RESUMEN

Importance: Preoperative chemo(radio)therapy is increasingly used in patients with localized pancreatic adenocarcinoma, leading to pathological complete response (pCR) in a small subset of patients. However, multicenter studies with in-depth data about pCR are lacking. Objective: To investigate the incidence, outcome, and risk factors of pCR after preoperative chemo(radio)therapy. Design, Setting, and Participants: This observational, international, multicenter cohort study assessed all consecutive patients with pathology-proven localized pancreatic adenocarcinoma who underwent resection after 2 or more cycles of chemotherapy (with or without radiotherapy) in 19 centers from 8 countries (January 1, 2010, to December 31, 2018). Data collection was performed from February 1, 2020, to April 30, 2022, and analyses from January 1, 2022, to December 31, 2023. Median follow-up was 19 months. Exposures: Preoperative chemotherapy (with or without radiotherapy) followed by resection. Main Outcomes and Measures: The incidence of pCR (defined as absence of vital tumor cells in the sampled pancreas specimen after resection), its association with OS from surgery, and factors associated with pCR. Factors associated with overall survival (OS) and pCR were investigated with Cox proportional hazards and logistic regression models, respectively. Results: Overall, 1758 patients (mean [SD] age, 64 [9] years; 879 [50.0%] male) were studied. The rate of pCR was 4.8% (n = 85), and pCR was associated with OS (hazard ratio, 0.46; 95% CI, 0.26-0.83). The 1-, 3-, and 5-year OS rates were 95%, 82%, and 63% in patients with pCR vs 80%, 46%, and 30% in patients without pCR, respectively (P < .001). Factors associated with pCR included preoperative multiagent chemotherapy other than (m)FOLFIRINOX ([modified] leucovorin calcium [folinic acid], fluorouracil, irinotecan hydrochloride, and oxaliplatin) (odds ratio [OR], 0.48; 95% CI, 0.26-0.87), preoperative conventional radiotherapy (OR, 2.03; 95% CI, 1.00-4.10), preoperative stereotactic body radiotherapy (OR, 8.91; 95% CI, 4.17-19.05), radiologic response (OR, 13.00; 95% CI, 7.02-24.08), and normal(ized) serum carbohydrate antigen 19-9 after preoperative therapy (OR, 3.76; 95% CI, 1.79-7.89). Conclusions and Relevance: This international, retrospective cohort study found that pCR occurred in 4.8% of patients with resected localized pancreatic adenocarcinoma after preoperative chemo(radio)therapy. Although pCR does not reflect cure, it is associated with improved OS, with a doubled 5-year OS of 63% compared with 30% in patients without pCR. Factors associated with pCR related to preoperative chemo(radio)therapy regimens and anatomical and biological disease response features may have implications for treatment strategies that require validation in prospective studies because they may not universally apply to all patients with pancreatic adenocarcinoma.


Asunto(s)
Adenocarcinoma , Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/terapia , Neoplasias Pancreáticas/cirugía , Neoplasias Pancreáticas/mortalidad , Masculino , Persona de Mediana Edad , Femenino , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/terapia , Adenocarcinoma/patología , Anciano , Terapia Neoadyuvante/métodos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Resultado del Tratamiento , Estudios de Cohortes , Oxaliplatino/uso terapéutico , Pancreatectomía
20.
Nat Med ; 30(6): 1711-1721, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38834850

RESUMEN

Despite the wide effects of cardiorespiratory fitness (CRF) on metabolic, cardiovascular, pulmonary and neurological health, challenges in the feasibility and reproducibility of CRF measurements have impeded its use for clinical decision-making. Here we link proteomic profiles to CRF in 14,145 individuals across four international cohorts with diverse CRF ascertainment methods to establish, validate and characterize a proteomic CRF score. In a cohort of around 22,000 individuals in the UK Biobank, a proteomic CRF score was associated with a reduced risk of all-cause mortality (unadjusted hazard ratio 0.50 (95% confidence interval 0.48-0.52) per 1 s.d. increase). The proteomic CRF score was also associated with multisystem disease risk and provided risk reclassification and discrimination beyond clinical risk factors, as well as modulating high polygenic risk of certain diseases. Finally, we observed dynamicity of the proteomic CRF score in individuals who undertook a 20-week exercise training program and an association of the score with the degree of the effect of training on CRF, suggesting potential use of the score for personalization of exercise recommendations. These results indicate that population-based proteomics provides biologically relevant molecular readouts of CRF that are additive to genetic risk, potentially modifiable and clinically translatable.


Asunto(s)
Capacidad Cardiovascular , Proteómica , Humanos , Proteómica/métodos , Masculino , Femenino , Persona de Mediana Edad , Factores de Riesgo , Adulto , Anciano , Estudios de Cohortes , Ejercicio Físico/fisiología
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