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1.
Circulation ; 147(11): 881-896, 2023 03 14.
Artículo en Inglés | MEDLINE | ID: mdl-36705030

RESUMEN

BACKGROUND: Cardiac chamber-selective transcriptional programs underpin the structural and functional differences between atrial and ventricular cardiomyocytes (aCMs and vCMs). The mechanisms responsible for these chamber-selective transcriptional programs remain largely undefined. METHODS: We nominated candidate chamber-selective enhancers (CSEs) by determining the genome-wide occupancy of 7 key cardiac transcription factors (GATA4, MEF2A, MEF2C, NKX2-5, SRF, TBX5, TEAD1) and transcriptional coactivator P300 in atria and ventricles. Candidate enhancers were tested using an adeno-associated virus-mediated massively parallel reporter assay. Chromatin features of CSEs were evaluated by performing assay of transposase accessible chromatin sequencing and acetylation of histone H3 at lysine 27-HiChIP on aCMs and vCMs. CSE sequence requirements were determined by systematic tiling mutagenesis of 29 CSEs at 5 bp resolution. Estrogen-related receptor (ERR) function in cardiomyocytes was evaluated by Cre-loxP-mediated inactivation of ERRα and ERRγ in cardiomyocytes. RESULTS: We identified 134 066 and 97 506 regions reproducibly occupied by at least 1 transcription factor or P300, in atria or ventricles, respectively. Enhancer activities of 2639 regions bound by transcription factors or P300 were tested in aCMs and vCMs by adeno-associated virus-mediated massively parallel reporter assay. This identified 1092 active enhancers in aCMs or vCMs. Several overlapped loci associated with cardiovascular disease through genome-wide association studies, and 229 exhibited chamber-selective activity in aCMs or vCMs. Many CSEs exhibited differential chromatin accessibility between aCMs and vCMs, and CSEs were enriched for aCM- or vCM-selective acetylation of histone H3 at lysine 27-anchored loops. Tiling mutagenesis of 29 CSEs identified the binding motif of ERRα/γ as important for ventricular enhancer activity. The requirement of ERRα/γ to activate ventricular CSEs and promote vCM identity was confirmed by loss of the vCM gene profile in ERRα/γ knockout vCMs. CONCLUSIONS: We identified 229 CSEs that could be useful research tools or direct therapeutic gene expression. We showed that chamber-selective multi-transcription factor, P300 occupancy, open chromatin, and chromatin looping are predictive features of CSEs. We found that ERRα/γ are essential for maintenance of ventricular identity. Finally, our gene expression, epigenetic, 3-dimensional genome, and enhancer activity atlas provide key resources for future studies of chamber-selective gene regulation.


Asunto(s)
Histonas , Miocitos Cardíacos , Humanos , Miocitos Cardíacos/metabolismo , Histonas/genética , Histonas/metabolismo , Estudio de Asociación del Genoma Completo , Lisina/genética , Lisina/metabolismo , Regiones Promotoras Genéticas , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Cromatina/genética , Cromatina/metabolismo , Elementos de Facilitación Genéticos/genética , Estrógenos
2.
Anaesthesia ; 77(11): 1228-1236, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36108342

RESUMEN

Nitrous oxide, a potent greenhouse gas, is a common labour analgesic. One method which may reduce its carbon footprint is to 'crack' the exhaled gas into nitrogen and oxygen using catalytic destruction. In this quality improvement project, based on environmental monitoring and staff feedback, we assessed the impact of nitrous oxide cracking technology in the maternity setting. Mean ambient nitrous oxide levels were recorded during the final 30 minutes of uncomplicated labour in 36 cases and plotted on a run chart. Interventions were implemented in four stages, comprising: stage 1, baseline (12 cases); stage 2, cracking with nitrous oxide delivered and scavenged via a mouthpiece (eight cases); stage 3, cracking with nitrous oxide via a facemask with an air-filled cushion (eight cases); stage 4, cracking with nitrous oxide via a low-profile facemask, and enhanced coaching on the use of the technology (eight cases). The median ambient nitrous oxide levels were 71% lower than baseline in stage 2 and 81% lower in stage 4. Staff feedback was generally positive, though some found the technology to be cumbersome; successful implementation relies on effective staff engagement. Our results indicate that cracking technology can reduce ambient nitrous oxide levels in the obstetric setting, with potential for reductions in environmental impacts and occupational exposure.


Asunto(s)
Gases de Efecto Invernadero , Exposición Profesional , Femenino , Humanos , Nitrógeno , Óxido Nitroso , Exposición Profesional/análisis , Exposición Profesional/prevención & control , Oxígeno , Embarazo , Mejoramiento de la Calidad , Tecnología
3.
Mikrochim Acta ; 189(7): 243, 2022 06 03.
Artículo en Inglés | MEDLINE | ID: mdl-35657569

RESUMEN

The development of the first microfluidic paper-based analytical device (µPAD) for the speciation of inorganic arsenic in environmental aqueous samples as arsenite (As(III)) and arsenate (As(V)) which implements hydride generation on a paper platform is described. The newly developed µPAD has a 3D configuration and uses Au(III) chloride as the detection reagent. Sodium borohydride is used to generate arsine in the device's sample zone by reducing As(III) in the presence of hydrochloric acid or both As(III) and As(V) (total inorganic As) in the presence of sulfuric acid. Arsine then diffuses across a hydrophobic porous polytetrafluoroethylene membrane into the device's detection zone where it reduces Au(III) to Au nanoparticles. This results in a color change which can be related to the concentration of As(III) or total inorganic As (i.e., As(III) and As(V)) concentration. Under optimal conditions, the µPAD is characterized by a limit of detection of 0.43 mg L-1 for total inorganic As (As(III) + As(V)) and 0.41 mg L-1 for As(III) and a linear calibration range in both cases of 1.2-8.0 mg As L-1. The newly developed µPAD-based method was validated by applying it to groundwater and freshwater samples and comparing the results with those obtained by conventional atomic spectrometric techniques.


Asunto(s)
Arsénico , Nanopartículas del Metal , Arsénico/análisis , Oro , Microfluídica , Agua/análisis
4.
J Shoulder Elbow Surg ; 31(12): 2506-2513, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36115618

RESUMEN

BACKGROUND: Radial head arthroplasty (RHA) is an important tool in the acute treatment of comminuted radial head and neck fractures. RHA is also performed in a delayed manner after failed open reduction and internal fixation, for fracture malunion or nonunion, and other chronic post-traumatic elbow disorders where restoration of the lateral column of the elbow is considered necessary. The relative efficacy and longevity of acute vs. delayed RHA is unknown. We sought to compare clinical, radiographic, and patient-reported outcomes between these groups. METHODS: We identified patients ≥18 years old who underwent an RHA between 2000 and 2018 and then extracted 135 total elbows with a mean follow-up of 2.3 years that sustained isolated radial head fractures (30%), terrible triad injuries (66%), or Essex-Lopresti injuries (4%). The acute cohort (RHA: <12 weeks) contained 101 elbows that underwent surgery at a mean of 0.6 weeks (range, 0 days to 7 weeks, 96% <2 weeks) from injury, whereas the delayed cohort (RHA: 12 weeks to 2 years) contained 34 elbows that underwent surgery at a mean of 36 weeks (range, 14-82 weeks) from injury. Patients in the acute group had a higher percentage of terrible triad injuries (75% vs. 40%, P < .001) and Mason 3 fractures (98% vs. 45%, P < .001). RESULTS: At the final follow-up, 13 of 101 patients in the acute cohort (13%) and 7 of 34 patients in the delayed cohort (21%) required implant revision or resection. A total of 25 patients (25%) in the acute cohort and 12 patients (35%) in the delayed cohort required a reoperation. Kaplan-Meier 2-year survival estimates free of implant resection or revision (90% acute, 86% delayed) and reoperation (76% acute, 70% delayed) were similar between groups. In patients with 5-year follow-up, there was an increased rate of revision or resection in the delayed group (30% vs. 13%). Two-year survival estimates free of radiographic loosening were 80% in the acute cohort vs. 57% in the delayed cohort (P = .04). Mayo Elbow Performance Score at 2 years demonstrated mean scores of 83 and 79 in the acute and delayed groups, respectively, with 71% of the acute cohort and 64% of the delayed cohort achieving good or excellent scores. CONCLUSIONS: Our results demonstrated that although 2-year Kaplan-Meier survival free of revision or resection estimates and reoperation rates was equivalent between the groups, the delayed group experienced worse Mayo Elbow Performance Score outcomes, a higher revision or resection rate at 5 years, and an increased rate of radiographic loosening.


Asunto(s)
Lesiones de Codo , Articulación del Codo , Fracturas del Radio , Humanos , Adolescente , Rango del Movimiento Articular , Estudios Retrospectivos , Resultado del Tratamiento , Fracturas del Radio/diagnóstico por imagen , Fracturas del Radio/cirugía , Articulación del Codo/diagnóstico por imagen , Articulación del Codo/cirugía , Artroplastia/métodos
5.
J Arthroplasty ; 37(6S): S286-S290, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35217185

RESUMEN

BACKGROUND: Accurately detecting early postoperative periprosthetic joint infection (PJI) following total hip arthroplasty (THA) and total knee arthroplasty (TKA) remains challenging. The purpose of our study was to determine the impact of antibiotics given prior to laboratory evaluation on the reliability of serologic and synovial fluid tests to identify PJI in the early postoperative period. METHODS: We identified 49,861 primary total hip arthroplasties and total knee arthroplasties performed between 2000 and 2019. Among these patients, 21 hips and 28 knees that underwent arthrocentesis within 12 weeks of their arthroplasty were identified as infected. Patients who had received antibiotics within 2 weeks prior to laboratory evaluation were compared to those who had not. Median values of C-reactive protein, erythrocyte sedimentation rate, synovial white blood cell (WBC) count, synovial neutrophil percentage, and synovial absolute neutrophil count were compared between groups. The false negative rate for detecting PJI using laboratory values was compared using published cutoffs for PJI in the early postoperative period. RESULTS: Median values of C-reactive protein (105 vs 22 mg/L; P = .006), synovial WBC count (57,591 vs 4,473 cells/µL; P = .003), synovial neutrophil percentage (94% vs 76%; P = .004), and synovial absolute neutrophil count (50,748 vs 2,804 cells/µL; P < .001) were significantly lower in patients who received antibiotics compared to those who did not. False negative rates for detecting PJI were significantly higher for synovial WBC and synovial neutrophil percentage in patients treated with antibiotics compared to untreated patients. CONCLUSION: False negative rates for detecting early PJI when using published cutoffs were markedly higher in antibiotic-treated patients compared to untreated patients for synovial WBC count and synovial neutrophil percentage. LEVEL OF EVIDENCE: Level IV retrospective review.


Asunto(s)
Artritis Infecciosa , Artroplastia de Reemplazo de Cadera , Infecciones Relacionadas con Prótesis , Antibacterianos/uso terapéutico , Artritis Infecciosa/etiología , Artroplastia de Reemplazo de Cadera/efectos adversos , Biomarcadores , Proteína C-Reactiva/análisis , Humanos , Infecciones Relacionadas con Prótesis/diagnóstico , Infecciones Relacionadas con Prótesis/tratamiento farmacológico , Infecciones Relacionadas con Prótesis/etiología , Reproducibilidad de los Resultados , Estudios Retrospectivos , Sensibilidad y Especificidad , Líquido Sinovial/química
6.
J Arthroplasty ; 37(3): 574-580, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34774687

RESUMEN

BACKGROUND: Diagnosing early periprosthetic joint infection (PJI) after primary total hip arthroplasty (THA) remains challenging. We sought to validate optimal laboratory value cutoffs for detecting early PJIs in a series of primary THAs from one institution. METHODS: We retrospectively identified 22,795 primary THAs performed between 2000 and 2019. Within 12 weeks, 43 hips (43 patients) underwent arthrocentesis. Patients were divided into 2 groups: evaluation ≤6 weeks or 6-12 weeks following THA. The 2011 Musculoskeletal Infection Society major criteria for PJI diagnosed PJI in 15 patients. Mann-Whitney U-tests were used to compare median laboratory values and receiver operating characteristic curve analysis was used to evaluate optimal cutoff values. RESULTS: Both within 6 weeks and between 6 and 12 weeks postoperatively, median C-reactive protein (CRP), erythrocyte sedimentation rate, synovial white blood cell (WBC) count, neutrophil percentage, and absolute neutrophil count (ANC) values were significantly higher in infected THAs. Optimal cutoffs within 6 weeks were: CRP ≥100 mg/L, synovial WBCs ≥4390 cells/µL, neutrophil percentage ≥74%, and ANC ≥3249 cells/µL. Between 6 and 12 weeks, optimal cutoffs were: CRP ≥33 mg/L, synovial WBCs ≥26,995 cells/µL, neutrophil percentage ≥93%, and ANC ≥25,645 cells/µL. CONCLUSION: Early PJI following THA should be suspected within 6 weeks with CRP ≥100 mg/L or synovial WBCs ≥4390 cells/µL. Between 6 and 12 weeks postoperatively, cutoffs of CRP ≥33 mg/L, synovial fluid WBC ≥26,995 cells/µL, and neutrophil percentage ≥93% diagnosed PJI with high accuracy. LEVEL OF EVIDENCE: Level IV Diagnostic.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Infecciones Relacionadas con Prótesis , Artroplastia de Reemplazo de Cadera/efectos adversos , Biomarcadores , Sedimentación Sanguínea , Proteína C-Reactiva/análisis , Humanos , Laboratorios , Infecciones Relacionadas con Prótesis/diagnóstico , Infecciones Relacionadas con Prótesis/etiología , Estudios Retrospectivos , Sensibilidad y Especificidad , Líquido Sinovial/química
7.
J Arthroplasty ; 36(7): 2359-2363, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33640184

RESUMEN

BACKGROUND: Consensus on whether low-dose (81 mg) or regular-dose (325 mg) aspirin (ASA) is more effective for venous thromboembolism (VTE) chemoprophylaxis in primary total joint arthroplasties (TJAs) is not reached. The goal of this study is to evaluate the efficacy of low-dose and regular-dose ASA for VTE chemoprophylaxis in primary total hip arthroplasties and total knee arthroplasties. METHODS: We retrospectively identified 3512 primary TJAs (2344 total hip arthroplasties and 1168 total knee arthroplasties) with ASA used as VTE chemoprophylaxis between 2000 and 2019. Patients received ASA twice daily for 4-6 weeks after surgery with 961 (27%) receiving low-dose ASA and 2551 (73%) receiving regular-dose ASA. The primary endpoint was 90-day incidence of symptomatic VTEs. Secondary outcomes were gastrointestinal (GI) bleeding events and mortality. The mean age at index TJA was 66 years, 54% were female, and mean body mass index was 31 kg/m2. The mean Charlson Comorbidity Index was 3.5. Mean follow-up was 3 years. RESULTS: There was no difference in 90-day incidence of symptomatic VTEs between low-dose and regular-dose ASA (0% vs 0.1%, respectively; P = .79). There were no GI bleeding events in either group. There was no difference in 90-day mortality between low-dose and regular-dose ASA (0.3% vs 0.1%, respectively; P = .24). CONCLUSION: In 3512 primary TJA patients treated with ASA, we found a cumulative incidence of VTE <1% at 90 days. Although this study is underpowered, it appears that twice daily low-dose ASA was equally effective to twice daily regular-dose ASA for VTE chemoprophylaxis, with no difference in risk of GI bleeds or mortality. LEVEL OF EVIDENCE: III, retrospective cohort study.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Tromboembolia Venosa , Anticoagulantes , Artroplastia de Reemplazo de Cadera/efectos adversos , Aspirina , Femenino , Humanos , Estudios Retrospectivos , Tromboembolia Venosa/epidemiología , Tromboembolia Venosa/etiología , Tromboembolia Venosa/prevención & control
8.
Field Crops Res ; 192: 78-85, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27307654

RESUMEN

Maintaining wheat productivity under the increasing temperatures in South Asia is a challenge. We focused on developing early maturing wheat lines as an adaptive mechanism in regions suffering from terminal heat stress and those areas that require wheat adapted to shorter cycles under continual high temperature stress. We evaluated the grain yield performance of early-maturing heat-tolerant germplasm developed by CIMMYT, Mexico at diverse locations in South Asia from 2009 to 2014 and estimated the breeding progress for high-yielding and early-maturing heat-tolerant germplasm in South Asia. Each year the trial comprised of 28 new entries, one CIMMYT check (Baj) and a local check variety. Locations were classified by mega environment (ME); ME1 being the temperate irrigated locations with terminal high temperature stress, and ME5 as hot, sub-tropical, irrigated locations. Grain yield (GY), days to heading (DTH) and plant height (PH) were recorded at each location. Effect of temperature on GY was observed in both ME1 and ME5. Across years, mean minimum temperatures in ME1 and mean maximum temperatures in ME5 during grain filling had significant negative association with GY. The ME1 locations were cooler that those in ME5 in the 5 years of evaluations and had a 1-2 t/ha higher GY. A mean reduction of 20 days for DTH and 20 cm in PH was observed in ME5. Negative genetic correlations of -0.43 to -0.79 were observed between GY and DTH in South Asia during 2009-2014. Each year, we identified early-maturing germplasm with higher grain yield than the local checks. A positive trend was observed while estimating the breeding progress across five years for high-yielding early-maturing heat tolerant wheat compared to the local checks in South Asia. The results suggests the potential of the high-yielding early-maturing wheat lines developed at CIMMYT in improving wheat production and maintaining genetic gains in South Asia.

9.
Transpl Infect Dis ; 17(1): 39-47, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25573269

RESUMEN

BACKGROUND: Staphylococcus aureus is among the most common causes of healthcare-associated infection (HAI) in the United States. Patients who have received a solid organ transplant (SOT) represent a unique population for the acquisition of HAIs, given their preoperative organ failure, immunosuppression, and need for invasive procedures. However, limited literature is published on S. aureus infections among children with SOT. We describe the epidemiology, antimicrobial susceptibility, and clinical features of S. aureus infections among pediatric SOT recipients. DESIGN: An ongoing prospective S. aureus surveillance database from 2001 to 2012 was searched for infections in patients with a history of SOT at Texas Children's Hospital. Medical records and antibiotic susceptibility profiles were reviewed; specific attention was applied to the time since transplantation to infection. RESULTS: Out of the total of 696 transplants performed during the study period, 38 pediatric SOT recipients developed 41 S. aureus infections; the highest incidence of infection was among heart recipients. Overall, the most common infectious diagnoses were skin-and-soft-tissue infections (66.1%), followed by bacteremia (15.3%). Among isolates in SOT patients, 47.5%, 16.9%, and 6.7% were resistant to methicillin, clindamycin, or mupirocin, respectively. Three infections (7.3%) occurred in the early post-transplant period (<1 month), all of which were bacteremia (P = 0.007) and all caused by methicillin-susceptible S. aureus (MSSA). The majority of infections (90.2%) occurred in the late post-transplant period (>6 months). In 10 cases (16.9%), S. aureus infection was associated with graft rejection during the same admission. CONCLUSIONS: S. aureus represents an important cause of morbidity in pediatric SOT recipients. While the majority of infections occurred late after transplant (>6 months), those acquired in the early post-transplant period were more often invasive and caused by MSSA in our hospital. Physicians caring for SOT recipients should be aware of the risks posed by this pathogen and the potential concomitant morbidity including graft rejection.


Asunto(s)
Trasplante de Órganos/efectos adversos , Infecciones de los Tejidos Blandos/epidemiología , Infecciones Estafilocócicas/epidemiología , Staphylococcus aureus/aislamiento & purificación , Adolescente , Antiinfecciosos/uso terapéutico , Bacteriemia , Niño , Infección Hospitalaria , Femenino , Humanos , Incidencia , Masculino , Estudios Prospectivos , Infecciones de los Tejidos Blandos/tratamiento farmacológico , Infecciones Estafilocócicas/tratamiento farmacológico , Staphylococcus aureus/efectos de los fármacos , Estados Unidos/epidemiología
10.
Rev Sci Instrum ; 95(6)2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38921057

RESUMEN

Magnetic nanoparticles (MNPs) are used extensively across numerous disciples, with applications including Magnetic Particle Imaging (MPI), targeted hyperthermia, deep brain stimulation, immunoassays, and thermometry. The assessment of MNPs, especially those being designed for MPI, is performed with magnetic particle spectrometers, relaxometers, loop tracers, or similar devices. Despite the many applications and the need for particle assessment, there are few consolidated resources for designing or building such a MNP assessment system. Here, we describe the design and performance of an open-source device capable of spectroscopy, relaxometry, and loop tracing. We show example measurements from the device and quantify the detection sensitivity by measuring a dilution series of Synomag-D 70 nm (from 0.5 mg Fe/ml to 7 ng Fe/ml) with a 10 mT drive field at 23.8 kHz. The device measures 260 pg Fe with SNR = 1 and 1.3 ng at SNR = 5 in spectroscopy mode in under one second of measurement time. The system has a dynamic range of 60 µg to 260 pg Fe without changing the hardware configuration. As an example application, we characterize Synomag-D's relaxation time constant for drive fields 2-18 mT and compare the magnetization responses of two commonly used MNPs.

11.
J Hosp Infect ; 143: 33-37, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38529780

RESUMEN

A large increase in hospital-onset and intensive-care-unit-onset Staphylococcus aureus bacteraemia rates in English acute trusts was observed between 2020 and 2021, coinciding with reported increases in coronavirus disease (COVID-19) cases and associated hospitalizations. Many of these S. aureus bacteraemia cases were defined as co-/secondary infections to COVID-19. Over the same period, increases in the percentage of ventilator-associated pneumonia-related bacteraemia were also found. The COVID-19 pandemic appears to have contributed to the increase in hospital-onset S. aureus bacteraemia in England; further studies are needed to better understand the impacts on patient outcomes.


Asunto(s)
Bacteriemia , COVID-19 , Infecciones Estafilocócicas , Humanos , Infecciones Estafilocócicas/epidemiología , Staphylococcus aureus , Bacteriemia/epidemiología , Medicina Estatal , Pandemias , Hospitales , Inglaterra/epidemiología , COVID-19/epidemiología
12.
J Anim Sci ; 1022024 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-38820137

RESUMEN

This experiment evaluated growth, physiological responses, and puberty attainment in beef heifers reared in drylots with a high stocking density, and provided or not with a moderate exercise regimen. A total of 180 heifers (75% Angus × 25% Brahman) were used in this experiment replicated over 2 yr. Each year, 90 heifers were ranked by age (264 ±â€…1 d) and body weight (BW on day -3; 200 ±â€…2 kg) on day 0, and assigned to a) one of six drylot pens (10 × 14 m pens; 10 heifers per pen) with a stocking density of 14 m2/heifer (DENS), or b) one of three pastures (2-ha pastures; 10 heifers per pasture) with a stocking density of 2,000 m2/heifer (CON). Beginning on day 15, three DENS pens were given access to an exercise area (DENS-EX) 3 times/wk (1 h). Negligible forage was available for CON, whereas heifers from all treatments received the same limit-fed diet (~13 kg/heifer daily). Shrunk BW was recorded after 16 h of feed and water withdrawal on days -3 and 225 to calculate BW gain. Temperament was evaluated on days 0, 128, and 224. Heifers were fitted with a pedometer behind their shoulder on day 0 to record physical activity. Pedometer results and blood samples were collected weekly for progesterone analysis. Hair samples from the tail switch were collected every 28 d. Data were analyzed with pen or pasture as an experimental unit, via ANOVA using the MIXED or GLIMMIX procedures of SAS (SAS Inst. Inc., Cary, NC). Heifers from CON had more (P < 0.01) steps per week compared with DENS and DENS-EX (23,973, 6,706, and 12,354 steps/wk, respectively; SEM = 1,247), and DENS-EX heifers had more (P < 0.01) steps per week compared with DENS. No treatment effects (P ≥ 0.91) were detected for heifer BW gain (~0.820 kg/d). Hair cortisol concentrations were greater (P ≤ 0.05) in DENS and DENS-EX compared with CON beginning on day 56. Exit velocity and temperament score were greater (P ≤ 0.05) in DENS compared with DENS-EX and CON on day 224. Puberty attainment was delayed (treatment × day; P < 0.01) in DENS compared with DENS-EX and CON. A greater (P ≤ 0.05) proportion of CON were pubertal by day 105 compared with DENS and DENS-EX (30.0%, 11.6%, and 15.0%, respectively; SEM = 6.5), while a greater (P < 0.05) proportion of CON and DENS-EX were pubertal by day 154 compared to DENS (61.7%, 66.7%, and 43.3%, respectively; SEM = 6.5). Rearing replacement heifers in drylots with high stocking density has detrimental effects on their puberty attainment, and the moderate exercise regimen partially alleviated this negative outcome.


Replacement beef heifers are often reared in drylots with high stocking density to facilitate feeding and management, or to intensify beef production as availability of grazing areas becomes limited. Studies from our group, however, demonstrated that drylot heifers experience delayed puberty attainment compared with heifers reared on pastures. This negative outcome was associated with chronic stress caused by confinement and restricted physical activity; the latter being a key animal welfare factor with direct effects on reproductive development. Based on this rationale, this experiment evaluated growth, stress-related physiological responses, and puberty attainment heifers reared in drylots and exposed or not to a moderate exercise regimen. Moreover, drylot heifers were compared to contemporary cohorts being reared on pasture. As expected, heifers reared in drylots experienced heightened stress-related physiological responses and delayed puberty attainment compared to pasture heifers. Exposing drylot heifers to the moderate exercise regimen did not alleviate the physiological consequences of chronic stress, but lessened the delay in puberty attainment compared with non-exercised drylot cohorts. Therefore, stocking density and exercise opportunities should be considered to improve heifer welfare and reproductive development in intensive drylot systems, as lack of exercise directly contributes to delayed reproductive development of drylot heifers.


Asunto(s)
Condicionamiento Físico Animal , Maduración Sexual , Animales , Bovinos/fisiología , Bovinos/crecimiento & desarrollo , Femenino , Crianza de Animales Domésticos/métodos , Vivienda para Animales , Densidad de Población , Progesterona/sangre , Hidrocortisona/sangre
13.
bioRxiv ; 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38464269

RESUMEN

In the last decade human iPSC-derived cardiomyocytes (hiPSC-CMs) proved to be valuable for cardiac disease modeling and cardiac regeneration, yet challenges with scale, quality, inter-batch consistency, and cryopreservation remain, reducing experimental reproducibility and limiting clinical translation. Here, we report a robust cardiac differentiation protocol that uses Wnt modulation and a stirred suspension bioreactor to produce on average 124 million hiPSC-CMs with >90% purity using a variety of hiPSC lines (19 differentiations; 10 iPSC lines). After controlled freeze and thaw, bioreactor-derived CMs (bCMs) showed high viability (>90%), interbatch reproducibility in cellular morphology, function, drug response and ventricular identity, which was further supported by single cell transcriptomes. bCMs on microcontact printed substrates revealed a higher degree of sarcomere maturation and viability during long-term culture compared to monolayer-derived CMs (mCMs). Moreover, functional investigation of bCMs in 3D engineered heart tissues showed earlier and stronger force production during long-term culture, and robust pacing capture up to 4 Hz when compared to mCMs. bCMs derived from this differentiation protocol will expand the applications of hiPSC-CMs by providing a reproducible, scalable, and resource efficient method to generate cardiac cells with well-characterized structural and functional properties superior to standard mCMs.

14.
J Environ Qual ; 42(4): 1213-25, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24216373

RESUMEN

On-site wastewater treatment systems (OWTSs) are commonly used by households in areas of low population density to treat household wastewater and recycle it back to the environment. However, new absorption field products of differing architecture types have recently become available. A 3-yr field study was conducted in Bethel Heights, northwest Arkansas to assess several newer architecture types (i.e., chambers, polystyrene-aggregate, and gravel-less pipe) relative to the traditional pipe-and-gravel design under wet- and dry-soil conditions. Thirteen products of four different architecture types were installed in 46-cm-deep trenches in a Captina silt loam (fine-silty, siliceous, active, mesic Typic Fragiudult). Products were evaluated based on in-trench solution storage measured with an electronic water-level sensor approximately weekly from January 2009 through January 2012. Between May 2010 and January 2012, the thickness of any biomat formation was measured approximately weekly by insertion of a wooden dowel through in-trench monitoring ports. Architecture type alone did not affect ( > 0.05) in-trench solution storage. However, solution storage among individual products differed under wet- and dry-soil conditions ( < 0.05). When present, biomat thickness differed significantly ( < 0.05) among all four architecture types, ranging from 1.4 to 6.2 cm thick on average in the pipe-and-aggregate and polystyrene-aggregate types, respectively. Regression analyses showed that biomat thickness increased in three products, did not change in nine products, and decreased in one product over time. Results showed that several currently approved alternative products had similar in-trench solution storage but that several alternative products also had greater solution storage than that of the traditional pipe-and-gravel system. With no observed effluent surfacing, the soil morphology approach appears to be adequate and appropriately environmentally conservative for assigning typical single-family loading rates to alternative OWTS products and to the traditional pipe-and-gravel system.


Asunto(s)
Suelo , Purificación del Agua , Arkansas , Eliminación de Residuos Líquidos , Aguas Residuales , Agua
15.
J Orthop Trauma ; 37(5): 230-236, 2023 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-36728865

RESUMEN

OBJECTIVES: To evaluate the association between preoperative international normalized ratio (INR) and postoperative mortality and other outcomes after hemiarthroplasty for geriatric femoral neck fractures. DESIGN: Retrospective cohort study. SETTING: A single Level-I trauma center. PATIENTS/PARTICIPANTS: Patients ≥55 years of age with OTA/AO 31B proximal femur fractures [1556 patients (1616 hips)]. INTERVENTION: Hip hemiarthroplasty. MAIN OUTCOME MEASUREMENTS: Ninety-day mortality, postoperative transfusion within 72 hours, and 90-day postoperative outcomes. RESULTS: Adjusting for confounders, the association of preoperative INR and 90-day mortality was not statistically significant [hazard ratio (HR): 1.3; 95% confidence interval (CI): 0.97, 1.8; P = 0.08]. Dementia (HR: 1.9; 95% CI: 1.4-2.6; P < 0.001), Charlson Comorbidity Index (HR: 1.1; 95% CI: 1.1-1.2; P < 0.001), and age by decade (HR: 1.4; 95% CI: 1.1-1.8; P = 0.002) were associated with 90-day mortality. Increasing INR was significantly associated with blood transfusion [odds ratio (OR) 1.4; 95% CI 1.03-1.6; P = 0.031]. Preoperative hemoglobin <10 g/dL (OR 13.7; 95% CI 8.4-23.3; P < 0.001) was also associated with a postoperative transfusion, whereas intraoperative tranexamic acid use (OR 0.3; 95% CI 0.2-0.5; P < 0.001) was inversely associated with postoperative transfusion rate. INR was associated with superficial wound infection (HR: 2.0; 95% CI: 1.1-3.7; P = 0.02) and noninfected wound complications (HR: 1.6; 95% CI: 1.1-2.4; P = 0.007). Risk of superficial infection increased when INR was >1.8. CONCLUSION: When controlling for confounders, preoperative INR was not significantly associated with 90-day mortality. Underlying medical conditions contribute to postoperative mortality more than an elevated INR. However, INR is associated with superficial wound complications. This risk becomes statistically significant as INR rises above 1.8. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.


Asunto(s)
Fracturas del Cuello Femoral , Hemiartroplastia , Humanos , Anciano , Estudios Retrospectivos , Hemiartroplastia/efectos adversos , Relación Normalizada Internacional , Fracturas del Cuello Femoral/cirugía , Modelos de Riesgos Proporcionales
16.
Arthrosc Sports Med Rehabil ; 5(2): e435-e444, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37101861

RESUMEN

Purpose: To (1) report the long-term outcomes associated with both operative and nonoperative management of capitellar osteochondritis dissecans (OCD), (2) identify factors associated with failure of nonoperative management, and (3) determine whether delay in surgery affects final outcomes. Methods: All patients who received a diagnosis of capitellar OCD from 1995-2020 within a geographic cohort were included. Medical records, imaging studies, and operative reports were manually reviewed to record demographic data, treatment strategies, and outcomes. The cohort was divided into 3 groups: (1) nonoperative management, (2) early surgery, and (3) delayed surgery. Delayed surgery (surgery ≥6 months after symptom onset) was considered failure of nonoperative management. Results: Fifty elbows with a mean follow-up period of 10.5 years (median, 10.3 years; range, 1-25 years) were studied. Of these, 7 (14%) were definitively treated nonoperatively, 16 (32%) underwent delayed surgery after at least 6 months of failed nonoperative treatment, and 27 (54%) underwent early surgical intervention. When compared with nonoperative management, surgical management resulted in superior Mayo Elbow Performance Index pain scores (40.1 vs 33, P = .04), fewer mechanical symptoms (9% vs 50%, P < .01), and better elbow flexion (141° vs 131°, P = .01) at long-term follow-up. Older patients trended toward increased failure of nonoperative management (P = .06). The presence of an intra-articular loose body predicted failure of nonoperative management (P = .01; odds ratio, 13). Plain radiography and magnetic resonance imaging had poor sensitivities for identifying loose bodies (27% and 40%, respectively). Differences in outcomes after early versus delayed surgical management were not observed. Conclusions: Nonoperative management of capitellar OCD failed 70% of the time. Elbows that did not undergo surgery had slightly more symptoms and decreased functional outcomes compared with those treated surgically. The greatest predictors of failure of nonoperative treatment were older age and presence of a loose body; however, an initial trial of nonoperative treatment did not adversely impact the success of future surgery. Level of Evidence: Level III, retrospective cohort study.

17.
bioRxiv ; 2023 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-37131696

RESUMEN

Understanding how the atrial and ventricular chambers of the heart maintain their distinct identity is a prerequisite for treating chamber-specific diseases. Here, we selectively inactivated the transcription factor Tbx5 in the atrial working myocardium of the neonatal mouse heart to show that it is required to maintain atrial identity. Atrial Tbx5 inactivation downregulated highly chamber specific genes such as Myl7 and Nppa , and conversely, increased the expression of ventricular identity genes including Myl2 . Using combined single nucleus transcriptome and open chromatin profiling, we assessed genomic accessibility changes underlying the altered atrial identity expression program, identifying 1846 genomic loci with greater accessibility in control atrial cardiomyocytes compared to KO aCMs. 69% of the control-enriched ATAC regions were bound by TBX5, demonstrating a role for TBX5 in maintaining atrial genomic accessibility. These regions were associated with genes that had higher expression in control aCMs compared to KO aCMs, suggesting they act as TBX5-dependent enhancers. We tested this hypothesis by analyzing enhancer chromatin looping using HiChIP and found 510 chromatin loops that were sensitive to TBX5 dosage. Of the loops enriched in control aCMs, 73.7% contained anchors in control-enriched ATAC regions. Together, these data demonstrate a genomic role for TBX5 in maintaining the atrial gene expression program by binding to atrial enhancers and preserving tissue-specific chromatin architecture of atrial enhancers.

18.
Nat Cardiovasc Res ; 2(10): 881-898, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38344303

RESUMEN

Understanding how the atrial and ventricular heart chambers maintain distinct identities is a prerequisite for treating chamber-specific diseases. Here, we selectively knocked out (KO) the transcription factor Tbx5 in the atrial working myocardium to evaluate its requirement for atrial identity. Atrial Tbx5 inactivation downregulated atrial cardiomyocyte (aCM) selective gene expression. Using concurrent single nucleus transcriptome and open chromatin profiling, genomic accessibility differences were identified between control and Tbx5 KO aCMs, revealing that 69% of the control-enriched ATAC regions were bound by TBX5. Genes associated with these regions were downregulated in KO aCMs, suggesting they function as TBX5-dependent enhancers. Comparing enhancer chromatin looping using H3K27ac HiChIP identified 510 chromatin loops sensitive to TBX5 dosage, and 74.8% of control-enriched loops contained anchors in control-enriched ATAC regions. Together, these data demonstrate TBX5 maintains the atrial gene expression program by binding to and preserving the tissue-specific chromatin architecture of atrial enhancers.

19.
Neural Netw ; 152: 353-369, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35598404

RESUMEN

A recent paper (Mhaskar (2020)) introduces a straightforward and simple kernel based approximation for manifold learning that does not require the knowledge of anything about the manifold, except for its dimension. In this paper, we examine how the pointwise error in approximation using least squares optimization based on similarly localized kernels depends upon the data characteristics and deteriorates as one goes away from the training data. The theory is presented with an abstract localized kernel, which can utilize any prior knowledge about the data being located on an unknown sub-manifold of a known manifold. We demonstrate the performance of our approach using a publicly available micro-Doppler data set, and investigate the use of different preprocessing measures, kernels, and manifold dimensions. Specifically, it is shown that the localized kernel introduced in the above mentioned paper when used with PCA components leads to a near-competitive performance to deep neural networks, and offers significant improvements in training speed and memory requirements. To demonstrate the fact that our methods are agnostic to the domain knowledge, we examine the classification problem in a simple video data set.


Asunto(s)
Gestos , Radar , Análisis de los Mínimos Cuadrados , Aprendizaje Automático , Redes Neurales de la Computación
20.
J Hosp Infect ; 119: 175-181, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34547320

RESUMEN

Increases in hospital-onset Klebsiella spp. and Pseudomonas aeruginosa bacteraemia rates in England were observed between August 2020 and February 2021 to the highest levels recorded since the start of mandatory surveillance in April 2017. Cases were extracted from England's mandatory surveillance database for key Gram-negative bloodstream infections. Incidence rates for hospital-onset bacteraemia cases increased from 8.9 (N=255) to 14.9 (N=394) per 100,000 bed-days for Klebsiella spp. [incidence rate ratio (IRR) 1.7, P<0.001], and from 4.9 (N=139) to 6.2 (N=164) per 100,000 bed-days for P. aeruginosa (IRR 1.3, P<0.001) (August 2020-February 2021). These incidence rates were higher than the average rates observed during the same period in the previous 3 years. These trends coincided with an increase in the percentage of hospital-onset bacteraemia cases that were also positive for severe acute respiratory syndrome coronavirus-2.


Asunto(s)
Bacteriemia , COVID-19 , Bacteriemia/epidemiología , Inglaterra/epidemiología , Hospitales , Humanos , Klebsiella , Pseudomonas aeruginosa , SARS-CoV-2 , Medicina Estatal
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