RESUMEN
Visual recognition is largely realized through neurons in the ventral stream, though recently, studies have suggested that ventrolateral prefrontal cortex (vlPFC) is also important for visual processing. While it is hypothesized that sensory and cognitive processes are integrated in vlPFC neurons, it is not clear how this mechanism benefits vision, or even if vlPFC neurons have properties essential for computations in visual cortex implemented via recurrence. Here, we investigated if vlPFC neurons in two male monkeys had functions comparable to visual cortex, including receptive fields, image selectivity, and the capacity to synthesize highly activating stimuli using generative networks. We found a subset of vlPFC sites show all properties, suggesting subpopulations of vlPFC neurons encode statistics about the world. Further, these vlPFC sites may be anatomically clustered, consistent with fMRI-identified functional organization. Our findings suggest that stable visual encoding in vlPFC may be a necessary condition for local and brain-wide computations.
Asunto(s)
Macaca mulatta , Imagen por Resonancia Magnética , Neuronas , Corteza Prefrontal , Corteza Visual , Corteza Prefrontal/fisiología , Corteza Prefrontal/citología , Corteza Prefrontal/diagnóstico por imagen , Animales , Masculino , Corteza Visual/fisiología , Corteza Visual/citología , Corteza Visual/diagnóstico por imagen , Neuronas/fisiología , Estimulación Luminosa , Percepción Visual/fisiología , Mapeo EncefálicoRESUMEN
BACKGROUND: Human parechovirus (HPeV) infection can result in severe disease in infants, including sepsis, seizures, brain injury, and death. In 2022, a resurgence of HPeV was noted in young infants. Spectrum of illness and outcomes remain to be fully described. METHODS: A multi-state retrospective cohort study was conducted to evaluate hospitalizations and outcomes of infants aged ≤6 months admitted in 2022 with laboratory-confirmed HPeV infection. Infants with severe disease were defined as having clinical seizures, or abnormalities on MRI or EEG during admission. Infants with severe vs non-severe disease were compared using descriptive statistics. RESULTS: 124 U.S. infants were identified with HPeV in 11 states. Cases of HPeV peaked in May and presented at a median of 25.8 days of life (0-194 d) with fever, fussiness, and poor feeding. Bacterial and other viral co-infections were rare. 33 (27%) of infants had severe neurologic disease, were more likely to present at an earlier age (13.9 vs 30 days of life, p<0.01), have preterm gestation (12% vs. 1%, p = 0.02), and present with respiratory symptoms (26% vs. 8%, p = 0.01) or apnea (41% vs. 1%, p <0.001). Subcortical white matter cytoxic cerebral edema was common in severe cases. Two infants with HPeV died during admission with severe neurologic HPeV disease; no infant with mild HPeV disease died. CONCLUSIONS: This is the largest, geographically-diverse U.S. study to describe the 2022 HPeV outbreak among infants. Longitudinal follow up of infants is needed to define predictors and outcomes of severe HPeV disease.
RESUMEN
Many proteins form paralogous multimers - molecular complexes in which evolutionarily related proteins are arranged into specific quaternary structures. Little is known about the mechanisms by which they acquired their stoichiometry (the number of total subunits in the complex) and heterospecificity (the preference of subunits for their paralogs rather than other copies of the same protein). Here we use ancestral protein reconstruction and biochemical experiments to study historical increases in stoichiometry and specificity during the evolution of vertebrate hemoglobin (Hb), a α2ß2 heterotetramer that evolved from a homodimeric ancestor after a gene duplication. We show that the mechanisms for this evolutionary transition was simple. One hydrophobic substitution in subunit ß after the gene duplication was sufficient to cause the ancestral dimer to homotetramerize with high affinity across a new interface. During this same interval, a single-residue deletion in subunit α at the older interface conferred specificity for the heterotetrameric form and the trans-orientation of subunits within it. These sudden transitions in stoichiometry and specificity were possible because the interfaces in Hb are isologous - involving the same surface patch on interacting subunits, rotated 180° relative to each other - but the symmetry is slightly imperfect. This architecture amplifies the impacts of individual mutations on stoichiometry and specificity, especially in higher-order complexes, and allows single substitutions to differentially affect heteromeric vs homomeric interactions. Many multimers are isologous, and symmetry in proteins is always imperfect; our findings therefore suggest that elaborate and specific molecular complexes may often evolve via simple genetic and physical mechanisms.
RESUMEN
The Antarctic Peninsula (West Antarctica) marine ecosystem has undergone substantial changes due to climate-induced shifts in atmospheric and oceanic temperatures since the 1950s. Using 25 years of satellite data (1998-2022), this study presents evidence that phytoplankton biomass and bloom phenology in the West Antarctic Peninsula are significantly changing as a response to anthropogenic climate change. Enhanced phytoplankton biomass was observed along the West Antarctic Peninsula, particularly in the early austral autumn, resulting in longer blooms. Long-term sea ice decline was identified as the main driver enabling phytoplankton growth in early spring and autumn, in parallel with a recent intensification of the Southern Annular Mode (2010-ongoing), which was observed to influence regional variability. Our findings contribute to the understanding of the complex interplay between environmental changes and phytoplankton responses in this climatically key region of the Southern Ocean and raise important questions regarding the far-reaching consequences that these ecological changes may have on global carbon sequestration and Antarctic food webs in the future.
Asunto(s)
Biomasa , Cambio Climático , Fitoplancton , Estaciones del Año , Fitoplancton/crecimiento & desarrollo , Regiones Antárticas , Cubierta de Hielo , Ecosistema , Océanos y Mares , Temperatura , EutrofizaciónRESUMEN
Jansen metaphyseal chondrodysplasia (JMC) is an ultra-rare disorder caused by germline heterozygous PTHR1 variants resulting in constitutive activation of parathyroid hormone type 1 receptor. A description of ocular manifestations of the disease is lacking. Six patients with JMC underwent a detailed ophthalmic evaluation, spectral-domain optical coherence tomography (OCT), visual field testing, and craniofacial CT scans. Five of 6 patients had good visual acuity. All patients had widely spaced eyes; 5/6 had downslanted palpebral fissures. One patient had proptosis, and another had bilateral ptosis. Two patients had incomplete closure of the eyelids (lagophthalmos), one had a history of progressive right facial nerve palsy with profuse epiphora, while the second had advanced optic nerve atrophy with corresponding retinal nerve fiber layer (RNFL) thinning on OCT and significant bilateral optic canal narrowing on CT scan. Additionally, this patient also had central visual field defects and abnormal color vision. A third patient had normal visual acuity, subtle temporal pallor of the optic nerve head, normal average RNFL, but decreased temporal RNFL and retinal ganglion cell layer analysis (GCA) on OCT. GCA was decreased in 4/6 patients indicating a subclinical optic nerve atrophic process. None of the patients had glaucoma or high myopia. These data represent the first comprehensive report of ophthalmic findings in JMC. Patients with JMC have significant eye findings associated with optic canal narrowing due to extensive skull base dysplastic bone overgrowth that appear to be more prevalent and pronounced with age. Progressive optic neuropathy from optic canal narrowing may be a feature of JMC, and OCT GCA can serve as a useful biomarker for progression in the setting of optic canal narrowing. We suggest that patients with JMC should undergo regular ophthalmic examination including color vision, OCT, visual field testing, orbital, and craniofacial imaging.
RESUMEN
BACKGROUND: Mineral metabolism is critical for proper development of hard tissues of the skeleton and dentition. The dentoalveolar complex includes the following 4 mineralized tissues: enamel, dentin, cementum, and alveolar bone. Developmental processes of these tissues are affected by inherited disorders that disrupt phosphate and pyrophosphate homeostasis, although manifestations are distinct from those in the skeleton. TYPES OF STUDIES REVIEWED: The authors discuss original data from experiments and comparative analyses and review articles describing effects of inherited phosphate and pyrophosphate disorders on dental tissues. A particular emphasis is placed on how new therapeutic approaches for these conditions may affect oral health and dental treatments of affected patients. RESULTS: Disorders of phosphate and pyrophosphate metabolism can lead to reduced mineralization (hypomineralization) or inappropriate (ectopic) calcification of soft tissues. Disruptions in phosphate levels in X-linked hypophosphatemia and hyperphosphatemic familial tumoral calcinosis and disruptions in pyrophosphate levels in hypophosphatasia and generalized arterial calcification of infancy contribute to dental mineralization defects. Traditionally, there have been few options to ameliorate dental health problems arising from these conditions. New antibody and enzyme replacement therapies bring possibilities to improve oral health in affected patients. PRACTICAL IMPLICATIONS: Research over the past 2 decades has exponentially expanded the understanding of mineral metabolism, and has led to novel treatments for mineralization disorders. Newly implemented and emerging therapeutic strategies affect the dentoalveolar complex and interact with aspects of oral health care that must be considered for dental treatment, clinical trial design, and coordination of multidisciplinary care teams.
RESUMEN
Ethanol consumption induces thymic atrophy and affects T cell maturation in the thymus. However, the mechanisms underlying such effects still need to be fully understood. We attempted to investigate the role of mineralocorticoid receptors (MR) on ethanol-induced thymic atrophy, T cell maturation dysfunction, and the role of oxidative stress in such responses. Male Wistar Hannover rats were treated with ethanol (20%; in volume ratio) and/or potassium canrenoate, an antagonist of MR (MRA; 30 mg/kg/day, gavage) for five weeks. Blockade of MR prevented ethanol-induced increases in the number of double-positive (CD4+CD8+), CD8+ single-positive (CD4-CD8+), CD4+ single-positive (CD4+CD8-), and Foxp3+CD4+ (Treg) cells in the thymus. Ethanol increased NOX2-derived superoxide (O2â¢-), lipoperoxidation, and superoxide dismutase (SOD) activity in the thymus. Pretreatment with the MRA fully prevented these responses. Apocynin, an antioxidant, prevented ethanol-induced increases in the number of double-positive and CD8+ single-positive cells but failed to prevent the rise in the number of CD4+ single-positive and Treg cells induced by ethanol. Apocynin, but not the MRA, prevented thymic atrophy induced by ethanol. Our findings provided novel evidence for the participation of MR in thymic dysfunction induced by ethanol consumption. Oxidative stress mediates the increase in double-positive and CD8+ single-positive cells in response to MR activation, while positive regulation of CD4+ single-positive and Treg cells is independent of oxidative stress. Oxidative stress is a significant mechanism of thymic atrophy associated with ethanol consumption, but this response is independent of MR activation.
RESUMEN
BACKGROUND: Cervical cancer incidence is rising in Puerto Rico (PR). Whether the increase is real or reflective of increased diagnostic scrutiny remains unclear. METHODS: Using data from the PR Central Cancer Registry for 2001-2019, we estimated trends of hysterectomy-corrected cervical cancer incidence and mortality rates, overall, and by stage at diagnosis and age. RESULTS: Overall, cervical cancer incidence (per 100,000) increased 1.6%/year (95% CI, -0.5% to 3.8%) from 12.5 to 15.3, with a prominent increase in distant-stage disease (4.5%/year [95% CI, 1.6% to 8.0%]), particularly among screening age eligible (25-64-year-old) women (5.8%/year [95% CI, 2.1% to 10.6%]). Mortality rates in this age-group remained stable during the study period. CONCLUSIONS: Increased occurrence of distant-stage disease among screening-eligible women is troubling and may reflect a real increase. Future research is needed to elucidate the factors underlying these trends. Improved prevention is also an urgent priority to reverse the rising cervical cancer incidence in PR.
Asunto(s)
Neoplasias del Cuello Uterino , Humanos , Femenino , Puerto Rico/epidemiología , Neoplasias del Cuello Uterino/epidemiología , Neoplasias del Cuello Uterino/diagnóstico , Neoplasias del Cuello Uterino/mortalidad , Incidencia , Persona de Mediana Edad , Adulto , Anciano , Adulto Joven , Estadificación de Neoplasias , Adolescente , Sistema de RegistrosRESUMEN
Machado-Joseph disease (MJD) is an autosomal dominant neurodegenerative spinocerebellar ataxia caused by a polyglutamine-coding CAG repeat expansion in the ATXN3 gene. While the CAG length correlates negatively with the age at onset, it accounts for approximately 50% of its variability only. Despite larger efforts in identifying contributing genetic factors, candidate genes with a robust and plausible impact on the molecular pathogenesis of MJD are scarce. Therefore, we analysed missense single nucleotide polymorphism variants in the PRKN gene encoding the Parkinson's disease-associated E3 ubiquitin ligase parkin, which is a well-described interaction partner of the MJD protein ataxin-3, a deubiquitinase. By performing a correlation analysis in the to-date largest MJD cohort of more than 900 individuals, we identified the V380L variant as a relevant factor, decreasing the age at onset by 3 years in homozygous carriers. Functional analysis in an MJD cell model demonstrated that parkin V380L did not modulate soluble or aggregate levels of ataxin-3 but reduced the interaction of the two proteins. Moreover, the presence of parkin V380L interfered with the execution of mitophagy-the autophagic removal of surplus or damaged mitochondria-thereby compromising cell viability. In summary, we identified the V380L variant in parkin as a genetic modifier of MJD, with negative repercussions on its molecular pathogenesis and disease age at onset.
Asunto(s)
Enfermedad de Machado-Joseph , Mitofagia , Ubiquitina-Proteína Ligasas , Enfermedad de Machado-Joseph/genética , Enfermedad de Machado-Joseph/patología , Humanos , Ubiquitina-Proteína Ligasas/genética , Mitofagia/genética , Mitofagia/fisiología , Masculino , Femenino , Persona de Mediana Edad , Adulto , Polimorfismo de Nucleótido Simple , Ataxina-3/genética , Edad de Inicio , Proteínas RepresorasRESUMEN
BACKGROUND: Parkinson's disease (PD) is the second most common neurodegenerative disease following Alzheimer's disease. Nearly 30 causative genes have been identified for PD and related disorders. However, most of these genes were identified in European-derived families, and little is known about their role in Latin American populations. OBJECTIVES: Our goal was to assess the spectrum and frequency of pathogenic variants in known PD genes in familial PD patients from Latin America. METHODS: We selected 335 PD patients with a family history of PD from the Latin American Research Consortium on the Genetics of PD. We capture-sequenced the coding regions of 26 genes related to neurodegenerative parkinsonism. Of the 335 PD patients, 324 had sufficient sequencing coverage to be analyzed. RESULTS: We identified pathogenic variants in 41 individuals (12.7%) in FBXO7, GCH1, LRRK2, PARK7, PINK1, PLA2G6, PRKN, SNCA, and TARDBP, GBA1 risk variants in 25 individuals (7.7%), and variants of uncertain significance in another 24 individuals (7.4%) in ATP13A2, ATP1A3, DNAJC13, DNAJC6, GBA1, LRKK2, PINK1, VPS13C, and VPS35. Of the 70 unique variants identified, 19 were more frequent in Latin Americans than in any other population. CONCLUSIONS: This is the first screening of known PD genes in a large cohort of patients with familial PD from Latin America. There were substantial differences in the spectrum of variants observed in comparison to previous findings from PD families of European origin. Our data provide further evidence that differences exist between the genetic architecture of PD in Latinos and European-derived populations. © 2024 The Author(s). Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.
RESUMEN
Klippel-Feil syndrome (KFS) is a rare congenital disorder characterized by the fusion of cervical vertebrae, limiting neck mobility, and often presenting with clinical manifestations such as neck pain, stiffness, and neurological deficits. While the classical presentation of KFS includes a "clinical triad" comprising a shortened neck, a low posterior hairline, and limited cervical motion, not all patients exhibit all three features. This case report presents an 81-year-old male with the complete KFS triad and underscores the diagnostic challenges and management strategies associated with this condition. Despite the rarity of KFS, understanding it is crucial for clinicians due to its profound implications on patient management and quality of life. This case emphasizes the importance of clinical suspicion in Internal Medicine, showcasing how an isolated presentation may often be a manifestation of an underlying congenital condition.
RESUMEN
Introduction: COPD and interstitial lung disease (ILD) are significant chronic respiratory disorders, impacting quality of life. Respiratory muscle roles and differences remain not entirely clear. The objective of the present study was to evaluate the degree of recruitment of the respiratory muscles and the work of breathing in COPD and ILD during exercise. Methods: We compared the sensory-mechanical relationships in COPD, ILD and healthy controls (n=20 each). They performed pulmonary function, noninvasive and invasive respiratory muscle strength, surface electromyography and work-of-breathing assessments. Results: COPD and ILD did not show lower static muscle strength compared to controls, but did show poor performance in the exercise test with increased transdiaphragmatic pressure (P di). In ILD, there was a higher increase in oesophageal pressure and a lower gastric pressure (P ga) on inspiration; in COPD, there was a significant increase in P ga on inspiration. In ILD, there is greater recruitment of accessory inspiratory muscles, whereas in COPD, there is marked use of both inspiratory and expiratory muscles. The neuromechanical inefficiency (increased neural respiratory drive without the corresponding tidal volume) was found in both diseases. In COPD, there is a considerable increase in elastic work to overcome intrinsic positive end-expiratory pressure (PEEPi) and expiratory work of breathing, whereas in ILD, non-PEEPi elastic work of breathing is the highest part of the total work of breathing. Conclusions: Early and increased activity of the respiratory muscles and work-of-breathing components significantly contribute to dyspnoea, exercise intolerance and neuromechanical inefficiency of ventilation in COPD and ILD. The mechanisms of P di generation were different between diseases.
RESUMEN
Introduction: Electronic health (e-Health) modalities effectively address healthcare access limitations; however, there are limited data on their adoption by Hispanic/Latina women who are disproportionally affected by health disparities. Methods: We conducted a cross-sectional study by disseminating an anonymous electronic questionnaire via social media to assess the perception of Hispanic/Latina women of reproductive age regarding facilitators and barriers for using e-Health modalities, including telemedicine and mobile apps, to monitor gynecologic health. Results: The questionnaire was completed by 351 Hispanic/Latina participants with high levels (98.3%) of advanced technological expertise. Current use of a gynecologic mobile app was reported by 63.8%, primarily for menstruation (85.1%) and ovulation (46.3%) tracking. While only 17.6% of participants were offered the option of a gynecologic consultation via telemedicine, the majority (90.5%) would agree to one. Higher education and advanced technological expertise correlated with acceptance of telemedicine for gynecological consults. Being younger (<29 y/o), a student, not having a preferred gynecologist and having a lower income significantly correlated with gynecologic mobile app acceptability. Conclusions: We showed that e-Health modalities are highly acceptable for Hispanic/Latina women of reproductive age to facilitate gynecological care and documented factors that are significantly associated with e-Health acceptability. These findings are relevant to public health emergencies that cause access to care limitations disproportionally affecting this already underserved population.
RESUMEN
OBJECTIVES: To examine the effect of local aqueous tobramycin injection adjunct to perioperative intravenous (IV) antibiotic prophylaxis in reducing fracture-related infections (FRIs) following reduction and internal fixation of open fractures. DESIGN: Retrospective cohort study. SETTING: Single academic Level I trauma center. PATIENTS SELECTION CRITERIA: Patients with open extremity fractures treated with reduction and internal fixation with (intervention group) or without (control group) 80 mg of local aqueous (2 mg/mL) tobramycin injected during closure at the time of definitive fixation were identified from December 2018 to August 2021 based on population-matched demographic and injury characteristics. OUTCOME MEASURES AND COMPARISONS: The primary outcome was FRI within 6 months of definitive fixation. Secondary outcomes consisted of fracture nonunion and bacterial speciation. Differences in outcomes between the 2 groups were assessed and logistic regression models were created to assess the difference in infection rates between groups, with and without controlling for potential confounding variables, such as sex, fracture location, and Gustilo-Anderson classification. RESULTS: An analysis of 157 patients was performed with 78 patients in the intervention group and 79 patients in the control group. In the intervention group, 30 (38.5%) patients were women with a mean age of 47.1 years. In the control group, 42 (53.2%) patients were women with a mean age of 46.4 years. The FRI rate was 11.5% in the intervention group compared with 25.3% in the control group ( P = 0.026). After controlling for sex, Gustilo-Anderson classification, and fracture location, the difference in FRI rates between groups remained significantly different ( P = 0.014). CONCLUSIONS: Local aqueous tobramycin injection at the time of definitive internal fixation of open extremity fractures was associated with a significant reduction in FRI rates when administered as an adjunct to intravenous antibiotics, even after controlling for potential confounding variables. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.
Asunto(s)
Antibacterianos , Profilaxis Antibiótica , Fijación Interna de Fracturas , Fracturas Abiertas , Infección de la Herida Quirúrgica , Tobramicina , Humanos , Femenino , Masculino , Tobramicina/administración & dosificación , Fracturas Abiertas/cirugía , Fracturas Abiertas/complicaciones , Persona de Mediana Edad , Estudios Retrospectivos , Antibacterianos/administración & dosificación , Infección de la Herida Quirúrgica/prevención & control , Profilaxis Antibiótica/métodos , AdultoRESUMEN
Rapidly waning immunity against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) requires continued global access to affordable vaccines. Globally, inactivated SARS-CoV-2 vaccines have been widely used during the SARS-CoV-2 pandemic. In this proof-of-concept study we adapted an original-D614G SARS-CoV-2 virus to Vero cell culture as a strategy to enhance inactivated vaccine manufacturing productivity. A passage 60 (P60) virus showed enhanced fitness and 50-fold increased virus yield in a bioreactor compared to the original-D614G virus. It further remained susceptible to neutralization by plasma from SARS-CoV-2 vaccinated and convalescent individuals, suggesting exposure of relevant epitopes. Monovalent inactivated P60 and bivalent inactivated P60/omicron BA.1 vaccines induced neutralizing responses against original-D614G and BA.1 viruses in mice and hamsters, demonstrating that the P60 virus is a suitable vaccine antigen. Antibodies further cross-neutralized delta and BA.5 viruses. Importantly, the inactivated P60 vaccine protected hamsters against disease upon challenge with original-D614G or BA.1 virus, with minimal lung pathology and lower virus loads in the upper and lower airways. Antigenicity of the P60 virus was thus retained compared to the original virus despite the acquisition of cell culture adaptive mutations. Consequently, cell culture adaptation may be a useful approach to increase yields in inactivated vaccine antigen production.
Asunto(s)
Anticuerpos Neutralizantes , Anticuerpos Antivirales , Vacunas contra la COVID-19 , COVID-19 , SARS-CoV-2 , Vacunas de Productos Inactivados , Animales , Células Vero , Chlorocebus aethiops , SARS-CoV-2/inmunología , Vacunas de Productos Inactivados/inmunología , Vacunas contra la COVID-19/inmunología , COVID-19/prevención & control , COVID-19/inmunología , COVID-19/virología , Ratones , Anticuerpos Antivirales/inmunología , Anticuerpos Antivirales/sangre , Anticuerpos Neutralizantes/inmunología , Anticuerpos Neutralizantes/sangre , Humanos , Protección Cruzada/inmunología , Cricetinae , FemeninoRESUMEN
OBJECTIVE: The objective of this study was to compare the quality of syndesmotic reduction with the ankle in maximal dorsiflexion versus neutral plantarflexion (normal resting position). METHODS: Baseline computed tomography (CT) imaging of 10 cadaveric ankle specimens from 5 donors was obtained with the ankles placed in normal resting position. Two fellowship-trained orthopaedic surgeons disrupted the syndesmosis of each ankle specimen. All ankles were then placed in neutral plantarflexion and were subsequently reduced with thumb pressure under direct visualization through an anterolateral approach and stabilized with one 0.062-inch K-wire placed from lateral to medial in a quadricortical fashion across the syndesmosis. Postreduction CT scans were then obtained with the ankle in normal resting position. This process was repeated with the ankles placed in maximal dorsiflexion during reduction and stabilization. Postreduction CT scans were then obtained with the ankles placed in normal resting position. All postreduction CT scans were compared with baseline CT imaging using mixed-effects linear regression with significance set at P < 0.05. RESULTS: Syndesmotic reduction and stabilization in maximal dorsiflexion led to increased external rotation of the fibula compared with baseline scans [13.0 ± 5.4 degrees (mean ± SD) vs. 7.5 ± 2.4 degrees, P = 0.002]. There was a tendency toward lateral translation of the fibula with the ankle reduced in maximal dorsiflexion (3.3 ± 1.0 vs. 2.7 ± 0.7 mm, P = 0.096). No other statistically significant differences between measurements of reduction with the ankle placed in neutral plantarflexion or maximal dorsiflexion compared with baseline were present (P > 0.05). CONCLUSIONS: Reducing the syndesmosis with the ankle in maximal dorsiflexion may lead to malreduction with external rotation of the fibula. There was no statistically significant difference in reduction quality with the ankle placed in neutral plantarflexion compared with baseline. Future studies should assess the clinical implications of ankle positioning during syndesmotic fixation.
Asunto(s)
Articulación del Tobillo , Cadáver , Humanos , Articulación del Tobillo/diagnóstico por imagen , Articulación del Tobillo/cirugía , Articulación del Tobillo/anatomía & histología , Articulación del Tobillo/fisiología , Traumatismos del Tobillo/cirugía , Traumatismos del Tobillo/diagnóstico por imagen , Masculino , Posicionamiento del Paciente , Femenino , Fracturas de Tobillo/cirugía , Fracturas de Tobillo/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Anciano , Persona de Mediana Edad , Fijación Interna de Fracturas/métodos , Rango del Movimiento Articular/fisiologíaRESUMEN
The lack of synthesized information regarding biodiversity is a major problem among researchers, leading to a pervasive cycle where ecologists make field campaigns to collect information that already exists and yet has not been made available for a broader audience. This problem leads to long-lasting effects in public policies such as spending money multiple times to conduct similar studies in the same area. We aim to identify this knowledge gap by synthesizing information available regarding two Brazilian long-term biodiversity programs and the metadata generated by them. Using a unique dataset containing 1904 metadata, we identified patterns of metadata distribution and intensity of research conducted in Brazil, as well as where we should concentrate research efforts in the next decades. We found that the majority of metadata were about vertebrates, followed by plants, invertebrates, and fungi. Caatinga was the biome with least metadata, and that there's still a lack of information regarding all biomes in Brazil, with none of them being sufficiently sampled. We hope that these results will have implications for broader conservation and management guiding, as well as to funding allocation programs.
Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales , Brasil , Conservación de los Recursos Naturales/métodos , Ecología , Monitoreo del Ambiente/métodosRESUMEN
OBJECTIVES: In the clinical routine of pediatricians, height is the most reliable indicator for assessing growth. However, there are situations where it is not possible to measure this parameter directly, making the estimation of height or length a useful alternative. The main goal of this study is to identify which segmental measure, including upper arm length (UAL), tibial length (TL), and knee-heel length (KHL), provides the stature estimate that most closely approximates directly measured height in the study participants. METHODS: Analytical cross-sectional study of the anthropometric and segmental measures of 248 participants, aged 0 to 14 years old, using Stevenson's and Kihara's equations to estimate indirectly measured height. RESULTS: The segmental measure that provided a measurement that deviated the least from the actual height was the KHL, followed by TL, both calculated using Stevenson's equations. CONCLUSION: The use of segmental measures to infer a child's stature is valuable in clinical practice, particularly in bedridden and incapacitated patients. Based on the present findings, the KHL and TL segments yielded more accurate results than the UAL.
RESUMEN
To meet the current demand for lead-free piezoelectric ceramics, a novel sol-gel synthesis route is presented for the preparation of Ba0.85Ca0.15Ti0.9Zr0.1O3 doped with cerium (Ce = 0, 0.01, and 0.02 mol%) and vanadium (V = 0, 0.3, and 0.4 mol%). X-ray diffraction patterns reveal the formation of a perovskite phase (space group P4mm) for all samples after calcination at 800 °C and sintering at 1250, 1350, and 1450 °C, where it is proposed that both dopants occupy the B site. Sintering studies show that V doping allows the sintering temperature to be reduced to at least 1250 °C. Undoped BCZT samples sintered at the same temperature show reduced functional properties compared to V-doped samples, i.e., d33 values increase by an order of magnitude with doping. The dissipation factor tan δ decreases with increasing sintering temperature for all doping concentrations, while the Curie temperature TC increases for all V-doped samples, reaching 120 °C for high-concentration co-doped samples. All results indicate that vanadium doping can facilitate the processing of BCZT at lower sintering temperatures without compromising performance while promoting thermal property stability.