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1.
J Hand Surg Am ; 2024 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-38980233

RESUMEN

Ulnar-sided wrist pain is a challenging clinical scenario due to multiple overlapping pathologies and involved anatomic structures. Advanced imaging such as magnetic resonance imaging can be used as an effective diagnostic adjunct if interpreted correctly. In this article, clinically relevant structures and radiographic correlates of the ulnar wrist are discussed and a corresponding systematic approach to reviewing magnetic resonance imaging is presented.

2.
Neurosurg Focus ; 57(1): E4, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38950430

RESUMEN

OBJECTIVE: The aim of this study was to compare injury circumstances, characteristics, and clinical management of emergency department (ED) presentations for sports-related concussion (SRC) and non-SRC. METHODS: This multicenter prospective observational study identified patients 5-17 years old who presented to EDs within 24 hours of head injury, with one or more signs or symptoms of concussion. Participants had a Glasgow Coma Scale score of 13-15 and no abnormalities on CT (if performed). Data were stratified by age: young children (5-8 years), older children (9-12 years), and adolescents (13-17 years). RESULTS: Of 4709 patients meeting the concussion criteria, non-SRC accounted for 56.3% of overall concussions, including 80.9% of younger child, 51.1% of older child, and 37.0% of adolescent concussions. The most common mechanism of non-SRC was falls for all ages. The most common activity accounting for SRC was bike riding for younger children, and rugby for older children and adolescents. Concussions occurring in sports areas, home, and educational settings accounted for 26.2%, 21.8%, and 19.0% of overall concussions. Concussions occurring in a sports area increased with age, while occurrences in home and educational settings decreased with age. The presence of amnesia significantly differed for SRC and non-SRC for all age groups, while vomiting and disorientation differed for older children and adolescents. Adolescents with non-SRC were admitted to a ward and underwent CT at higher proportions than those with SRC. CONCLUSIONS: Non-SRC more commonly presented to EDs overall, with SRC more common with increasing age. These data provide important information to inform public health policies, guidelines, and prevention efforts.


Asunto(s)
Traumatismos en Atletas , Conmoción Encefálica , Servicio de Urgencia en Hospital , Humanos , Niño , Conmoción Encefálica/epidemiología , Conmoción Encefálica/diagnóstico , Conmoción Encefálica/terapia , Masculino , Femenino , Servicio de Urgencia en Hospital/estadística & datos numéricos , Adolescente , Preescolar , Traumatismos en Atletas/epidemiología , Estudios Prospectivos , Escala de Coma de Glasgow
3.
Nat Commun ; 15(1): 5083, 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38877043

RESUMEN

Complex oxides offer rich magnetic and electronic behavior intimately tied to the composition and arrangement of cations within the structure. Rare earth iron garnet films exhibit an anisotropy along the growth direction which has long been theorized to originate from the ordering of different cations on the same crystallographic site. Here, we directly demonstrate the three-dimensional ordering of rare earth ions in pulsed laser deposited (EuxTm1-x)3Fe5O12 garnet thin films using both atomically-resolved elemental mapping to visualize cation ordering and X-ray diffraction to detect the resulting order superlattice reflection. We quantify the resulting ordering-induced 'magnetotaxial' anisotropy as a function of Eu:Tm ratio using transport measurements, showing an overwhelmingly dominant contribution from magnetotaxial anisotropy that reaches 30 kJ m-3 for garnets with x = 0.5. Control of cation ordering on inequivalent sites provides a strategy to control matter on the atomic level and to engineer the magnetic properties of complex oxides.

4.
Diabetes Metab Res Rev ; 40(5): e3829, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38850100

RESUMEN

AIMS: Pancreatic polypeptide (PP) is elevated in people with vascular risk factors such as type 2 diabetes or increased visceral fat. We investigated potential relationships between PP and microvascular and macrovascular complications of diabetes. MATERIALS AND METHODS: Animal study: Subcutaneous PP infusion for 4 weeks in high fat diet mouse model. Retinal mRNA submitted for Ingenuity Pathway Analysis. Human study: fasting PP measured in 1478 participants and vascular complications recorded over median 5.5 (IQR 4.9-5.8) years follow-up. RESULTS: Animal study: The retinal transcriptional response to PP was indicative of cellular stress and damage, and this footprint matched responses described in previously published studies of retinal disease. Of mechanistic importance the transcriptional landscape was consistent with upregulation of folliculin, a recently identified susceptibility gene for diabetic retinopathy. Human study: Adjusting for established risk factors, PP was associated with prevalent and incident clinically significant retinopathy (odds ratio (OR) 1.289 (1.107-1.501) p = 0.001; hazard ratio (HR) 1.259 (1.035-1.531) p = 0.0213), albuminuria (OR 1.277 (1.124-1.454), p = 0.0002; HR 1.608 (1.208-2.141) p = 0.0011), and macrovascular disease (OR 1.021 (1.006-1.037) p = 0.0068; HR 1.324 (1.089-1.61), p = 0.0049), in individuals with type 2 diabetes, and progression to diabetes in non-diabetic individuals (HR 1.402 (1.081-1.818), p = 0.0109). CONCLUSIONS: Elevated fasting PP is independently associated with vascular complications of diabetes and affects retinal pathways potentially influencing retinal neuronal survival. Our results suggest possible new roles for PP-fold peptides in the pathophysiology of diabetes complications and vascular risk stratification.


Asunto(s)
Diabetes Mellitus Tipo 2 , Angiopatías Diabéticas , Retinopatía Diabética , Ayuno , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/patología , Humanos , Masculino , Femenino , Persona de Mediana Edad , Angiopatías Diabéticas/etiología , Angiopatías Diabéticas/epidemiología , Animales , Ratones , Estudios de Seguimiento , Retinopatía Diabética/etiología , Retinopatía Diabética/epidemiología , Retinopatía Diabética/patología , Pronóstico , Incidencia , Biomarcadores/análisis , Factores de Riesgo , Anciano
5.
Oncogene ; 43(28): 2135-2142, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38839942

RESUMEN

This review explores the topic of microRNAs (miRNAs) for improved early detection of imperceptible cancers, with potential to advance precision medicine and improve patient outcomes. Historical research exploring miRNA's role in cancer detection collectively revealed initial hurdles in identifying specific miRNA signatures for early-stage and difficult-to-detect cancers. Early studies faced challenges in establishing robust biomarker panels and overcoming the heterogeneity of cancer types. Despite this, recent developments have supported the potential of miRNAs as sensitive and specific biomarkers for early cancer detection as well as having demonstrated remarkable potential as diagnostic tools for imperceptible cancers, such as those with elusive symptoms or challenging diagnostic criteria. This review discusses the advent of high-throughput technologies that have enabled comprehensive detection and profiling of unique miRNA signatures associated with early-stage cancers. Furthermore, advancements in bioinformatics and machine-learning techniques are considered, exploring the integration of multi-omics data which have potential to enhance both the accuracy and reliability of miRNA-based cancer detection assays. Finally, perspectives on the continuing development on technologies as well as discussion around challenges that remain, such as the need for standardised protocols and addressing the complex interplay of miRNAs in cancer biology are conferred.


Asunto(s)
Biomarcadores de Tumor , Técnicas Biosensibles , Detección Precoz del Cáncer , Aprendizaje Automático , MicroARNs , Neoplasias , Humanos , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/sangre , Neoplasias/genética , Neoplasias/diagnóstico , Neoplasias/sangre , Detección Precoz del Cáncer/métodos , MicroARNs/sangre , MicroARNs/genética , Técnicas Biosensibles/métodos , Biología Computacional/métodos
6.
Appl Environ Microbiol ; : e0222023, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38916294

RESUMEN

Methyl-coenzyme M reductase (MCR) catalyzes the final step of methanogenesis, the microbial metabolism responsible for nearly all biological methane emissions to the atmosphere. Decades of biochemical and structural research studies have generated detailed insights into MCR function in vitro, yet very little is known about the interplay between MCR and methanogen physiology. For instance, while it is routinely stated that MCR catalyzes the rate-limiting step of methanogenesis, this has not been categorically tested. In this study, to gain a more direct understanding of MCR's control on the growth of Methanosarcina acetivorans, we generate a strain with an inducible mcr operon on the chromosome, allowing for careful control of MCR expression. We show that MCR is not growth rate-limiting in substrate-replete batch cultures. However, through careful titration of MCR expression, growth-limiting state(s) can be obtained. Transcriptomic analysis of M. acetivorans experiencing MCR limitation reveals a global response with hundreds of differentially expressed genes across diverse functional categories. Notably, MCR limitation leads to strong induction of methylsulfide methyltransferases, likely due to insufficient recycling of metabolic intermediates. In addition, the mcr operon is not transcriptionally regulated, i.e., it is constitutively expressed, suggesting that the overabundance of MCR might be beneficial when cells experience nutrient limitation or stressful conditions. Altogether, we show that there is a wide range of cellular MCR concentrations that can sustain optimal growth, suggesting that other factors such as anabolic reactions might be rate-limiting for methanogenic growth. IMPORTANCE: Methane is a potent greenhouse gas that has contributed to ca. 25% of global warming in the post-industrial era. Atmospheric methane is primarily of biogenic origin, mostly produced by microorganisms called methanogens. Methyl-coenzyme M reductase (MCR) catalyzes methane formatio in methanogens. Even though MCR comprises ca. 10% of the cellular proteome, it is hypothesized to be growth-limiting during methanogenesis. In this study, we show that Methanosarcina acetivorans cells grown in substrate-replicate batch cultures produce more MCR than its cellular demand for optimal growth. The tools outlined in this study can be used to refine metabolic models of methanogenesis and assay lesions in MCR in a higher-throughput manner than isolation and biochemical characterization of pure protein.

8.
Brain Inj ; : 1-9, 2024 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-38704842

RESUMEN

OBJECTIVE: To identify differential trajectories of neurocognitive outcomes following pediatric concussion and investigate predictors associated with patterns of recovery up to 3 months. METHODS: 74 participants aged 8-17 years completed attention/working memory, processing speed, and executive function measures at 2 weeks, 1 month, and 3 months post-injury. We used principal component analysis to generate a composite of information processing. Group-based trajectory modeling identified latent trajectories. Multinominal logistic regression was used to examine associations between risk factors and trajectory groups. RESULTS: We identified three trajectories of neurocognitive outcomes. The medium (54.6%) and high improving groups (35.8%) showed ongoing increase in information processing, while the low persistent group showed limited change 3 months post-injury. This group recorded below average scores on Digit Span Forward and Backward at 3 months. History of pre-injury headache was significantly associated with the persistent low scoring group, relative to the medium improving (p = 0.03) but not the high improving group (p = 0.09). CONCLUSIONS: This study indicates variability in neurocognitive outcomes according to three differential trajectories, with groups partially distinguished by preexisting child factors (history of frequent headaches). Modelling that accounts for heterogeneity in individual outcomes is essential to identify clinically meaningful indices that are indicative of children requiring intervention.

9.
Viruses ; 16(5)2024 04 30.
Artículo en Inglés | MEDLINE | ID: mdl-38793596

RESUMEN

The concurrent seropositivity of HBsAg and anti-HBs has been described among patients with chronic hepatitis B (CHB), but its prevalence is variable. HBV S-gene mutations can affect the antigenicity of HBsAg. Patients with mutations in the 'α' determinant region of the S gene can develop severe HBV reactivation under immunosuppression. In this study at a tertiary liver center in the United States, we evaluated the frequency and virological characteristics of the HBsAg mutations among CHB patients with the presence of both HBsAg and anti-HBs. In this cohort, 45 (2.1%) of 2178 patients were identified to have a coexistence of HBsAg and anti-HBs, and 24 had available sera for the genome analysis of the Pre-S1, Pre-S2, and S regions. The frequency of mutations in the S gene was significantly higher among those older than 50 years (mean 8.5 vs. 5.4 mutations per subject, p = 0.03). Twelve patients (50%) had mutations in the 'α' determinant region of the S gene. Mutations at amino acid position 126 were most common in eight subjects. Three had a mutation at position 133. Only one patient had a mutation at position 145-the classic vaccine-escape mutation. Despite the universal HBV vaccination program, the vaccine-escape mutant is rare in our cohort of predominantly Asian patients.


Asunto(s)
Anticuerpos contra la Hepatitis B , Antígenos de Superficie de la Hepatitis B , Virus de la Hepatitis B , Hepatitis B Crónica , Mutación , Centros de Atención Terciaria , Humanos , Antígenos de Superficie de la Hepatitis B/genética , Antígenos de Superficie de la Hepatitis B/inmunología , Femenino , Masculino , Persona de Mediana Edad , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/inmunología , Adulto , Anticuerpos contra la Hepatitis B/sangre , Anticuerpos contra la Hepatitis B/inmunología , Hepatitis B Crónica/virología , Hepatitis B Crónica/inmunología , Hepatitis B Crónica/epidemiología , Estados Unidos/epidemiología , Evasión Inmune/genética , Anciano , Prevalencia , Adulto Joven
10.
J Clin Neurosci ; 125: 168-174, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38820856

RESUMEN

BACKGROUND: Ventriculoperitoneal (VP) shunt insertion is a means of diverting cerebrospinal fluid (CSF) for management of hydrocephalus. Revision rates, operating time, and length of stay (LOS) following laparoscopic insertion of the distal catheter have been mixed. There are limited data on the role of adhesiolysis during VP shunt insertion. Valve characteristics have also been shown to influence patient outcomes. There is a paucity of Australian data reporting on the effect of these variables on shunt outcomes. We aimed to study patient demographics, indications, and surgical and instrument variables in the Australian context. METHODS: We performed a retrospective, multi-surgeon, single-centre analysis of VP shunts inserted in adults via an open or laparoscopic technique. Data on patient demographics and surgery characteristics were collected from the hospital medical records and the Australasian Shunt Registry. The primary outcome was shunt revision rate and secondary outcomes were postoperative complications, operating time and LOS, and shunt survivability. RESULTS: Fifty-six participants were eligible for analysis. The overall revision rate was 14.3 %, which was lower than the national average. The distal catheter revision rate was 0 %. Laparoscopic insertion of the distal catheter was shown to significantly reduce operating time (70.4 min in the open group and 50.7 min in the laparoscopic group, p < 0.001). This was demonstrated across different aetiologies, and when controlling for age and valve-type (p < 0.05). The revision rate of non-programmable was higher than programmable valves (42.9 % versus 2.9 %, respectively). There were no differences between previous abdominal surgery, LOS, complication, or revision rate between open and laparoscopic insertion. VP shunt survivability was greater in the laparoscopic group (90-day shunt survival of 96.7 % and 92 % in the laparoscopy and open groups, respectively; p > 0.05). We did not find any significant difference in operating time or length of stay for age, sex, or previous abdominal surgery, even when accounting for surgical technique. Indication and shunt survivability varied widely between age groups. The use of laparoscopic insertion increased over time, though surgeons did not crossover techniques. CONCLUSIONS: The overall distal revision rate of VP shunts is low. Laparoscopic insertion of the distal catheter reduces operating time and may improve shunt survivability. Larger studies are needed to confirm differences in shunt survivability in open versus laparoscopic distal catheter insertion, between age groups, clinical indications, and valve type on patient outcomes.


Asunto(s)
Hidrocefalia , Laparoscopía , Derivación Ventriculoperitoneal , Humanos , Derivación Ventriculoperitoneal/métodos , Derivación Ventriculoperitoneal/efectos adversos , Estudios Retrospectivos , Masculino , Femenino , Persona de Mediana Edad , Australia , Hidrocefalia/cirugía , Anciano , Adulto , Laparoscopía/métodos , Reoperación/estadística & datos numéricos , Tiempo de Internación/estadística & datos numéricos , Resultado del Tratamiento , Complicaciones Posoperatorias/epidemiología , Anciano de 80 o más Años , Adulto Joven , Tempo Operativo
11.
Inorg Chem ; 63(15): 6571-6575, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38572833

RESUMEN

Structure-porosity relationships for metal-organic polyhedra (MOPs) are hardly investigated because they tend to be amorphized after activation, which inhibits crystallographic characterization. Here, we show a mixed-ligand strategy to statistically distribute two distinct carbazole-type ligands within rhodium-based octahedral MOPs, leading to systematic tuning of the microporosity in the resulting amorphous solids.

12.
J Neurotrauma ; 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38661521

RESUMEN

Children often experience mental health difficulties after a concussion. Yet, the extent to which a concussion precipitates or exacerbates mental health difficulties remains unclear. This study aimed to examine psychological predictors of mental health difficulties after pediatric concussion. Children (aged 5 to <18 years, M=11.7, SD=3.3) with concussion were recruited in a single-site longitudinal prospective cohort study conducted at a tertiary children's hospital (n=115, 73.9% male). The primary outcomes included internalizing (anxious, depressed, withdrawn behaviors), externalizing (risk-taking, aggression, attention difficulties), and total mental health problems, as measured by the Child Behavior Checklist at two weeks (acute) and three months (post-acute) after concussion. Predictors included parents' retrospective reports of premorbid concussive symptoms (Post-Concussion Symptom Inventory; PCSI), the child and their family's psychiatric history, child-rated perfectionism (Adaptive-Maladaptive Perfectionism Scale), and child-rated resilience (Youth Resilience Measure). Higher premorbid PCSI ratings consistently predicted acute and post-acute mental health difficulties. This relationship was significantly moderated by child psychiatric history. Furthermore, pre-injury learning difficulties, child psychiatric diagnoses, family psychiatric history, lower resilience, previous concussions, female sex, and older age at injury were associated with greater mental health difficulties after concussion. Pre-injury factors accounted for 23.4-39.9% of acute mental health outcomes, and 32.3-37.8% of post-acute mental health outcomes. When acute mental health was factored into the model, a total of 47.0%-68.8% of variance was explained by the model. Overall, in this sample of children, several pre-injury demographic and psychological factors were observed to predict mental health difficulties after a concussion. These findings need to be validated in future research involving larger, multi-site studies that include a broader cohort of children after concussion.

13.
Front Microbiol ; 15: 1362714, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38655084

RESUMEN

Introduction: Acute febrile illnesses (AFI) in developing tropical and sub-tropical nations are challenging to diagnose due to the numerous causes and non-specific symptoms. The proliferation of rapid diagnostic testing and successful control campaigns against malaria have revealed that non-Plasmodium pathogens still contribute significantly to AFI burden. Thus, a more complete understanding of local trends and potential causes is important for selecting the correct treatment course, which in turn will reduce morbidity and mortality. Next-generation sequencing (NGS) in a laboratory setting can be used to identify known and novel pathogens in individuals with AFI. Methods: In this study, plasma was collected from 228 febrile patients tested negative for malaria at clinics across Senegal from 2020-2022. Total nucleic acids were extracted and converted to metagenomic NGS libraries. To identify viral pathogens, especially those present at low concentration, an aliquot of each library was processed with a viral enrichment panel and sequenced. Corresponding metagenomic libraries were also sequenced to identify non-viral pathogens. Results and Discussion: Sequencing reads for pathogens with a possible link to febrile illness were identified in 51/228 specimens, including (but not limited to): Borrelia crocidurae (N = 7), West Nile virus (N = 3), Rickettsia felis (N = 2), Bartonella quintana (N = 1), human herpesvirus 8 (N = 1), and Saffold virus (N = 1). Reads corresponding to Plasmodium falciparum were detected in 19 specimens, though their presence in the cohort was likely due to user error of rapid diagnostic testing or incorrect specimen segregation at the clinics. Mosquito-borne pathogens were typically detected just after the conclusion of the rainy season, while tick-borne pathogens were mostly detected before the rainy season. The three West Nile virus strains were phylogenetically characterized and shown to be related to both European and North American clades. Surveys such as this will increase the understanding of the potential causes of non-malarial AFI, which may help inform diagnostic and treatment options for clinicians who provide care to patients in Senegal.

14.
bioRxiv ; 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38659931

RESUMEN

Glial cells of the enteric nervous system (ENS) interact closely with the intestinal epithelium and secrete signals that influence epithelial cell proliferation and barrier formation in vitro. Whether these interactions are important in vivo, however, is unclear because previous studies reached conflicting conclusions [1]. To better define the roles of enteric glia in steady state regulation of the intestinal epithelium, we characterized the glia in closest proximity to epithelial cells and found that the majority express PLP1 in both mice and humans. To test their functions using an unbiased approach, we genetically depleted PLP1+ cells in mice and transcriptionally profiled the small and large intestines. Surprisingly, glial loss had minimal effects on transcriptional programs and the few identified changes varied along the gastrointestinal tract. In the ileum, where enteric glia had been considered most essential for epithelial integrity, glial depletion did not drastically alter epithelial gene expression but caused a modest enrichment in signatures of Paneth cells, a secretory cell type important for innate immunity. In the absence of PLP1+ glia, Paneth cell number was intact, but a subset appeared abnormal with irregular and heterogenous cytoplasmic granules, suggesting a secretory deficit. Consistent with this possibility, ileal explants from glial-depleted mice secreted less functional lysozyme than controls with corresponding effects on fecal microbial composition. Collectively, these data suggest that enteric glia do not exert broad effects on the intestinal epithelium but have an essential role in regulating Paneth cell function and gut microbial ecology.

15.
J Neurotrauma ; 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38597719

RESUMEN

Of the four million children who experience a concussion each year, 30-50% of children will experience delayed recovery, where they will continue to experience symptoms more than two weeks after their injury. Delayed recovery from concussion encompasses emotional, behavioral, physical, and cognitive symptoms, and as such, there is an increased focus on developing an objective tool to determine risk of delayed recovery. This study aimed to identify a blood protein signature predictive of delayed recovery from concussion in children. Plasma samples were collected from children who presented to the Emergency Department at the Royal Children's Hospital, Melbourne, within 48h post-concussion. This study involved a discovery and validation phase. For the discovery phase, untargeted proteomics analysis was performed using single window acquisition of all theoretical mass spectra to identify blood proteins differentially abundant in samples from children with and without delayed recovery from concussion. A subset of these proteins was then validated in a separate participant cohort using multiple reaction monitoring and enzyme linked immunosorbent assay. A blood protein signature predictive of delayed recovery from concussion was modeled using a Support Vector Machine, a machine learning approach. In the discovery phase, 22 blood proteins were differentially abundant in age- and sex-matched samples from children with (n = 9) and without (n = 9) delayed recovery from concussion, six of whom were chosen for validation. In the validation phase, alpha-1-ACT was shown to be significantly lower in children with delayed recovery (n = 12) compared with those without delayed recovery (n = 28), those with orthopedic injuries (n = 7) and healthy controls (n = 33). A model consisting of alpha-1-ACT concentration stratified children based on recovery from concussion with an 0.88 area under the curve. We have identified that alpha-1-ACT differentiates between children at risk of delayed recovery from those without delayed recovery from concussion. To our knowledge, this is the first study to identify alpha-1-ACT as a potential marker of delayed recovery from concussion in children. Multi-site studies are required to further validate this finding before use in a clinical setting.

16.
Animals (Basel) ; 14(6)2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38539967

RESUMEN

Ewe lambs that are heavier due to improved nutrition pre- and post-weaning achieve puberty at a younger age, are more fertile, and have a higher reproductive rate. Fatness is intimately linked to reproduction, and we hypothesised that higher body condition scores at breeding would have positive effects on the reproductive rate of ewe lambs over and above liveweight. We also expected that if only a proportion of ewe lambs were presented for breeding, then it would be more effective to select them based on both liveweight and body condition score. To test these hypotheses, we analysed data from over 17,000 records from Merino and non-Merino ewe lambs from 22 different flocks across Australia. Non-Merino ewe lambs were more fertile (69.4% vs. 48.7%) and achieved a higher reproductive rate than Merino ewe lambs (96.9% vs. 60.7%). There were significant curvilinear relationships between liveweight (p < 0.001) or body condition score (p < 0.001) prior to breeding and reproductive rate for both Merino and non-Merino ewe lambs. For both breeds, there was a significant (p < 0.001) quadratic effect of body condition score prior to breeding on reproductive rate, independent of the correlated changes in liveweight, and at the same liveweight, an extra 0.5 of a body condition score up to 3.3 improved reproductive rate by about 20%. Nevertheless, the results indicated that if only a proportion of ewe lambs were selected for breeding, then selection based on both liveweight and body condition scores may only improve the overall reproductive rate by 1 to 2% compared to selection based on liveweight alone. We conclude that liveweight is a more effective method than body condition score for selecting ewe lambs for breeding.

17.
Ann Biomed Eng ; 52(5): 1393-1402, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38446329

RESUMEN

Osteochondral grafting has demonstrated positive outcomes for treating articular cartilage defects by replacing the damaged region with a cylindrical graft consisting of bone with a layer of cartilage. However, factors that cause graft subsidence are not well understood. The aim of this study was to develop finite element (FE) models of osteochondral grafts within a tibiofemoral joint, suitable for an investigation of parameters affecting graft stability. Cadaveric femurs were used to experimentally calibrate the bone properties and graft-bone frictional forces for use in corresponding image-based FE models, generated from µCT scan data. Effects of cartilage defects and osteochondral graft repair were measured by examining contact pressure changes using further in vitro tests. Here, six defects were created in the femoral condyles, which were subsequently treated with osteochondral autografts or metal pins. Matching image-based FE models were created, and the contact patches were compared. The bone material properties and graft-bone frictional forces were successfully calibrated from the initial tests with good resulting levels of agreement (CCC = 0.87). The tibiofemoral joint experiment provided a range of cases that were accurately described in the resultant pressure maps and were well represented in the FE models. Cartilage defects and repair quality were experimentally measurable with good agreement in the FE model pressure maps. Model confidence was built through extensive validation and sensitivity testing. It was found that specimen-specific properties were required to accurately represent graft behaviour. The final models produced are suitable for a range of parametric testing to investigate immediate graft stability.


Asunto(s)
Cartílago Articular , Articulación Tibiofemoral , Humanos , Análisis de Elementos Finitos , Cartílago Articular/diagnóstico por imagen , Cartílago Articular/cirugía , Articulación de la Rodilla/diagnóstico por imagen , Articulación de la Rodilla/cirugía , Huesos
18.
J Neurosurg Pediatr ; 33(6): 610-618, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38457794

RESUMEN

OBJECTIVE: Posttraumatic headache (PTH) represents the most common acute and persistent symptom in children after concussion, yet there is no blood protein signature to stratify the risk of PTH after concussion to facilitate early intervention. This discovery study aimed to identify capillary blood protein markers, at emergency department (ED) presentation within 48 hours of concussion, to predict children at risk of persisting PTH at 2 weeks postinjury. METHODS: Capillary blood was collected using the Mitra Clamshell device from children aged 8-17 years who presented to the ED of the Royal Children's Hospital, Melbourne, Australia, within 48 hours of sustaining a concussion. Participants were followed up at 2 weeks postinjury to determine PTH status. PTH was defined per clinical guidelines as a new or worsened headache compared with preinjury. An untargeted proteomics analysis using data-independent acquisition (DIA) was performed. Principal component analysis and hierarchical clustering were used to reduce the dimensionality of the protein dataset. RESULTS: A total of 907 proteins were reproducibly identified from 82 children within 48 hours of concussion. The mean participant age was 12.78 years (SD 2.54 years, range 8-17 years); 70% of patients were male. Eighty percent met criteria for acute PTH in the ED, while one-third of participants with follow-up experienced PTH at 2 weeks postinjury (range 8-16 days). Hemoglobin subunit zeta (HBZ), cystatin B (CSTB), beta-ala-his dipeptidase (CNDP1), hemoglobin subunit gamma-1 (HBG1), and zyxin (ZYX) were weakly associated with PTH at 2 weeks postinjury based on up to a 7% increase in the PTH group despite nonsignificant Benjamini-Hochberg adjusted p values. CONCLUSIONS: This discovery study determined that no capillary blood protein markers, measured at ED presentation within 48 hours of concussion, can predict children at risk of persisting PTH at 2 weeks postinjury. While HBZ, CSTB, CNDP1, HBG1, and ZYX were weakly associated with PTH at 2 weeks postinjury, there was no specific blood protein signature predictor of PTH in children after concussion. There is an urgent need to discover new blood biomarkers associated with PTH to facilitate risk stratification and improve clinical management of pediatric concussion.


Asunto(s)
Biomarcadores , Conmoción Encefálica , Cefalea Postraumática , Humanos , Niño , Masculino , Adolescente , Femenino , Biomarcadores/sangre , Conmoción Encefálica/sangre , Conmoción Encefálica/complicaciones , Cefalea Postraumática/etiología , Cefalea Postraumática/sangre , Proteómica , Capilares
19.
Nat Chem Biol ; 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38480981

RESUMEN

A common approach for understanding how drugs induce their therapeutic effects is to identify the genetic determinants of drug sensitivity. Because 'chemo-genetic profiles' are performed in a pooled format, inference of gene function is subject to several confounding influences related to variation in growth rates between clones. In this study, we developed Method for Evaluating Death Using a Simulation-assisted Approach (MEDUSA), which uses time-resolved measurements, along with model-driven constraints, to reveal the combination of growth and death rates that generated the observed drug response. MEDUSA is uniquely effective at identifying death regulatory genes. We apply MEDUSA to characterize DNA damage-induced lethality in the presence and absence of p53. Loss of p53 switches the mechanism of DNA damage-induced death from apoptosis to a non-apoptotic death that requires high respiration. These findings demonstrate the utility of MEDUSA both for determining the genetic dependencies of lethality and for revealing opportunities to potentiate chemo-efficacy in a cancer-specific manner.

20.
J Viral Hepat ; 31(6): 320-323, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38483043

RESUMEN

Hepatitis C core antigen (HCVcAg) is becoming increasingly recognized as an alternative to molecular testing for the confirmation of chronic hepatitis C. However, there are limited data on the performance of this assay in a genotype 3 (GT3) predominant country like Pakistan. We conducted a study to evaluate the diagnostic performance of HCVcAg against the HCV polymerase chain reaction (PCR) molecular test. HCV antibody-positive patients requiring confirmatory testing were recruited from August to October 2018 at the Pakistan Kidney and Liver Institute and Research Center (PKLI&RC), Lahore, Pakistan. Patients with previously known diagnoses or treatment histories were excluded. The Abbott HCV Ag assay was used for HCVcAg testing. Results ≥3.00 fmol/L were considered positive for HCVcAg. The Abbott RealTime HCV assay was used for PCR testing with a lower detection limit of ≥12 IU/mL. We computed the sensitivity, specificity and correlation of HCVcAg against HCV PCR. A total of 394 patients were recruited. The median age of the patients was 42 years. Most participants were females (51.5%, n = 203), 30.7% (n = 121) had HTN, 10.4% DM (n = 41) and 5% had APRI ≥2. The overall sensitivity was 98.0% and the specificity was 98.6%. The lowest detection limit of cAg was an HCV RNA value of 4657 IU/mL. The levels of cAg were highly correlated with those of HCV RNA by Spearman's rank correlation test (r = 0.935, p < .001). HCVcAg represents a suitable alternative with high sensitivity and specificity compared with HCV PCR in the GT3-predominant population and can be incorporated into algorithms to improve linkage to care.


Asunto(s)
Genotipo , Hepacivirus , Antígenos de la Hepatitis C , Hepatitis C Crónica , Reacción en Cadena de la Polimerasa , Sensibilidad y Especificidad , Proteínas del Núcleo Viral , Humanos , Femenino , Masculino , Pakistán , Hepacivirus/genética , Hepacivirus/inmunología , Adulto , Persona de Mediana Edad , Hepatitis C Crónica/diagnóstico , Hepatitis C Crónica/virología , Proteínas del Núcleo Viral/genética , Proteínas del Núcleo Viral/inmunología , Antígenos de la Hepatitis C/sangre , Reacción en Cadena de la Polimerasa/métodos , Adulto Joven , Anciano , ARN Viral
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