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1.
Ann Bot ; 130(1): 11-25, 2022 07 19.
Artículo en Inglés | MEDLINE | ID: mdl-35143612

RESUMEN

BACKGROUND AND AIMS: The entangled relationship of chromosome number and genome size with species distribution has been the subject of study for almost a century, but remains an open question due to previous ecological and phylogenetic knowledge constraints. To better address this subject, we used the clade Maxillariinae, a widely distributed and karyotypically known orchid group, as a model system to infer such relationships in a robust methodological framework. METHODS: Based on the literature and new data, we gathered the chromosome number and genome size for 93 and 64 species, respectively. We built a phylogenetic hypothesis and assessed the best macroevolutionary model for both genomic traits. Additionally, we collected together ecological data (preferences for bioclimatic variables, elevation and habit) used as explanatory variables in multivariate phylogenetic models explaining genomic traits. Finally, the impact of polyploidy was estimated by running the analyses with and without polyploids in the sample. KEY RESULTS: The association between genomic and ecological data varied depending on whether polyploids were considered or not. Without polyploids, chromosome number failed to present consistent associations with ecological variables. With polyploids, there was a tendency to waive epiphytism and colonize new habitats outside humid forests. The genome size showed association with ecological variables: without polyploids, genome increase was associated with flexible habits, with higher elevation and with drier summers; with polyploids, genome size increase was associated with colonizing drier environments. CONCLUSIONS: The chromosome number and genome size variations, essential but neglected traits in the ecological niche, are shaped in the Maxillariinae by both neutral and adaptive evolution. Both genomic traits are partially correlated to bioclimatic variables and elevation, even when controlling for phylogenetic constraints. While polyploidy was associated with shifts in the environmental niche, the genome size emerges as a central trait in orchid evolution by the association between small genome size and epiphytism, a key innovation to Neotropical orchid diversification.


Asunto(s)
Orchidaceae , Poliploidía , Cromosomas , Tamaño del Genoma , Hábitos , Orchidaceae/genética , Filogenia
2.
J Exp Zool B Mol Dev Evol ; 336(7): 576-584, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34496131

RESUMEN

Studies in Evo-Devo benefit from the use of a variety of organisms, as comparative approaches provide a better understanding of Biodiversity and Evolution. Standardized protocols to incubate eggs and manipulate embryo development enable postulation of additional species as suitable biological systems for research in the field. In the past decades, vertebrate lineages such as Squamata (lizards, snakes, and amphisbaenians) emerged as crucial study systems for addressing topics as diverse as phenotypic evolution and climate change. However, protocols for maintaining gravid females and incubating eggs in the lab under experimental conditions are available to only a few squamate species. This resource article presents a simple incubation guide that standardizes conditions to maintain embryos of Tropidurus catalanensis (Squamata: Tropiduridae) under different experimental conditions, manipulating relevant environmental factors like temperature and humidity. We identified associated effects relating the egg incubation condition to developmental stage, incubation time, hatching success, and resulting morphotypes. Temperature and humidity play a key role in development and require attention when establishing the experimental design. Current literature comprises information for Tropidurus lizards that ponders how general in Squamata are the ecomorphs originally described for Anolis. Studies evaluating phenotypic effects of developmental environments suggest plasticity in some of the traits that characterize the ecomorphological associations described for this family. We expect that this incubation guide encourages future studies using Tropidurus lizards to address Evo-Devo questions.


Asunto(s)
Lagartos , Óvulo , Animales , Laboratorios
3.
Ecology ; 100(2): e02541, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30707454

RESUMEN

Epiphytes are hyper-diverse and one of the frequently undervalued life forms in plant surveys and biodiversity inventories. Epiphytes of the Atlantic Forest, one of the most endangered ecosystems in the world, have high endemism and radiated recently in the Pliocene. We aimed to (1) compile an extensive Atlantic Forest data set on vascular, non-vascular plants (including hemiepiphytes), and lichen epiphyte species occurrence and abundance; (2) describe the epiphyte distribution in the Atlantic Forest, in order to indicate future sampling efforts. Our work presents the first epiphyte data set with information on abundance and occurrence of epiphyte phorophyte species. All data compiled here come from three main sources provided by the authors: published sources (comprising peer-reviewed articles, books, and theses), unpublished data, and herbarium data. We compiled a data set composed of 2,095 species, from 89,270 holo/hemiepiphyte records, in the Atlantic Forest of Brazil, Argentina, Paraguay, and Uruguay, recorded from 1824 to early 2018. Most of the records were from qualitative data (occurrence only, 88%), well distributed throughout the Atlantic Forest. For quantitative records, the most common sampling method was individual trees (71%), followed by plot sampling (19%), and transect sampling (10%). Angiosperms (81%) were the most frequently registered group, and Bromeliaceae and Orchidaceae were the families with the greatest number of records (27,272 and 21,945, respectively). Ferns and Lycophytes presented fewer records than Angiosperms, and Polypodiaceae were the most recorded family, and more concentrated in the Southern and Southeastern regions. Data on non-vascular plants and lichens were scarce, with a few disjunct records concentrated in the Northeastern region of the Atlantic Forest. For all non-vascular plant records, Lejeuneaceae, a family of liverworts, was the most recorded family. We hope that our effort to organize scattered epiphyte data help advance the knowledge of epiphyte ecology, as well as our understanding of macroecological and biogeographical patterns in the Atlantic Forest. No copyright restrictions are associated with the data set. Please cite this Ecology Data Paper if the data are used in publication and teaching events.

4.
Can J Surg ; 62(1): 7-8, 2019 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-30693741

RESUMEN

Posterior spinal instrumentation and fusion (PSIF) has been the standard operative treatment for adolescent idiopathic scoliosis (AIS) and is one of the most frequently performed elective pediatric surgeries in North America, incurring an expenditure of more than $1.1 billion annually in the United States alone. This commentary reflects on the outcomes of systematically implementing intraoperative skull femoral traction (IOSFT) combined with navigated sequential drilling (NSD) during PSIF for AIS as strategies for quality improvement at our tertiary children's hospital.


Asunto(s)
Mejoramiento de la Calidad , Escoliosis/cirugía , Fusión Vertebral/métodos , Adolescente , Trasplante Óseo/métodos , Niño , Estudios de Cohortes , Femenino , Hospitales Pediátricos , Humanos , Fijadores Internos , Masculino , América del Norte , Estudios Retrospectivos , Escoliosis/diagnóstico por imagen , Índice de Severidad de la Enfermedad , Tracción/métodos , Resultado del Tratamiento
5.
Ecology ; 99(2): 497, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29266462

RESUMEN

South America holds 30% of the world's avifauna, with the Atlantic Forest representing one of the richest regions of the Neotropics. Here we have compiled a data set on Brazilian Atlantic Forest bird occurrence (150,423) and abundance samples (N = 832 bird species; 33,119 bird individuals) using multiple methods, including qualitative surveys, mist nets, point counts, and line transects). We used four main sources of data: museum collections, on-line databases, literature sources, and unpublished reports. The data set comprises 4,122 localities and data from 1815 to 2017. Most studies were conducted in the Florestas de Interior (1,510 localities) and Serra do Mar (1,280 localities) biogeographic sub-regions. Considering the three main quantitative methods (mist net, point count, and line transect), we compiled abundance data for 745 species in 576 communities. In the data set, the most frequent species were Basileuterus culicivorus, Cyclaris gujanensis, and Conophaga lineata. There were 71 singletons, such as Lipaugus conditus and Calyptura cristata. We suggest that this small number of records reinforces the critical situation of these taxa in the Atlantic Forest. The information provided in this data set can be used for macroecological studies and to foster conservation strategies in this biodiversity hotspot. No copyright restrictions are associated with the data set. Please cite this Data Paper if data are used in publications and teaching events.

6.
Zoolog Sci ; 35(4): 373-381, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30079829

RESUMEN

Feeding specialization is a recurrent issue in the evolution of snakes and is sometimes associated to morphological and/or behavioral adaptations that improve snake performance to exploit a particular food type. Despite its importance for animal fitness, the role of physiological traits has been much less studied than morphological and behavioral traits in the evolution of feeding specialization in snakes. In this context, the energetic cost of post-prandial period is an important physiological factor due to the remarkable effect on the snake energy budget. We collected data on post-prandial metabolic rate (SDA) in five species of pit vipers from the genus Bothrops with different degrees of mammal feeding specialization to test the hypothesis that feeding specialist species have lower energy costs during the digestion of their regular food item when compared to species with a more generalist diet. Our results support this hypothesis and suggest that ontogenetic changes in diet can be accompanied by changes in energy cost of the digestion process.


Asunto(s)
Bothrops/fisiología , Metabolismo Energético/fisiología , Periodo Posprandial/fisiología , Envejecimiento , Animales , Bothrops/clasificación , Especificidad de la Especie
7.
An Acad Bras Cienc ; 90(4): 3693-3703, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30365703

RESUMEN

Over the last three years, Brazil has been ranked among the three largest producers of papaya. This study aimed to evaluate the acceptance and commercial standard of papaya fruits according to their sensory traits and provide information about the organoleptic and qualitative aspects of the fruit. Ten papaya genotypes grown in Linhares-ES were investigated, arranged in a randomized block design with four replications. Ten fruits from each genotype were randomly collected from each replication, which totaled 40 fruits per genotype. The fruit harvest was performed at stage 1 of maturation. The following genotypes were assessed: hybrids UC13, UC14, UC15 and UC16, from the 'Solo' group; hybrids UC03, UC10 and UC12, from the 'Formosa' group; and 'Golden', 'Calimosa' and 'Tainung 01', which were used as controls. The sensory evaluation of the genotypes was carried out in full balanced design by 50 evaluators. When submitted to sensory analysis, the hybrids showed high performance compared to the controls of each group. Traits such as aroma, flavor and overall impression were crucial in the selection carried out by the appraisers of the hybrids assessed. The hybrids UC10, UC12, UC14 and UC16 were the most accepted and preferred, respectively, in purchase intention.


Asunto(s)
Carica/química , Comportamiento del Consumidor , Frutas/química , Gusto , Brasil , Análisis de los Alimentos , Genotipo , Fenotipo
8.
J Exp Biol ; 219(Pt 11): 1649-58, 2016 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-26994181

RESUMEN

Anti-predatory behaviour evolves under the strong action of natural selection because the success of individuals avoiding predation essentially defines their fitness. Choice of anti-predatory strategies is defined by prey characteristics as well as environmental temperature. An additional dimension often relegated in this multilevel equation is the ontogenetic component. In the tegu Salvator merianae, adults run away from predators at high temperatures but prefer fighting when it is cold, whereas juveniles exhibit the same flight strategy within a wide thermal range. Here, we integrate physiology and morphology to understand ontogenetic variation in the temperature-dependent shift of anti-predatory behaviour in these lizards. We compiled data for body shape and size, and quantified enzyme activity in hindlimb and head muscles, testing the hypothesis that morphophysiological models explain ontogenetic variation in behavioural associations. Our prediction is that juveniles exhibit body shape and muscle biochemistry that enhance flight strategies. We identified biochemical differences between muscles mainly in the LDH:CS ratio, whereby hindlimb muscles were more glycolytic than the jaw musculature. Juveniles, which often use evasive strategies to avoid predation, have more glycolytic hindlimb muscles and are much smaller when compared with adults 1-2 years old. Ontogenetic differences in body shape were identified but marginally contributed to behavioural variation between juvenile and adult tegus, and variation in anti-predatory behaviour in these lizards resides mainly in associations between body size and muscle biochemistry. Our results are discussed in the ecological context of predator avoidance by individuals differing in body size living at temperature-variable environments, where restrictions imposed by the cold could be compensated by specific phenotypes.


Asunto(s)
Tamaño Corporal , Lagartos/anatomía & histología , Lagartos/fisiología , Músculo Esquelético/anatomía & histología , Músculo Esquelético/química , Conducta Predatoria/fisiología , Envejecimiento/fisiología , Animales , Modelos Lineales , Carácter Cuantitativo Heredable
9.
Planta Med ; 82(15): 1368-1373, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27485816

RESUMEN

Dihydroergotamine is a semisynthetic natural product derived from ergotamine, an ergot alkaloid. It is used to treat migraines, a neurological disease characterized by recurrent moderate to severe headaches. In this work, the in vitro metabolism of dihydroergotamine was evaluated in a biomimetic phase I reaction, aiming to verify all possible formed metabolites. Dihydroergotamine was submitted to an in vitro metabolism assay using rat liver microsomes, and the metabolites were analyzed by HPLC-MS/MS. The biomimetic reactions were performed with Jacobsen catalyst for scaling up production of oxidized metabolites. Two hydroxylated metabolites were isolated and characterized by MS/MS and 1H NMR analysis.


Asunto(s)
Dihidroergotamina/metabolismo , Dihidroergotamina/farmacocinética , Microsomas Hepáticos/metabolismo , Animales , Clorobenzoatos/metabolismo , Cromatografía Líquida de Alta Presión , Humanos , Hidroxilación , Inactivación Metabólica , Espectroscopía de Resonancia Magnética , Masculino , Microsomas Hepáticos/efectos de los fármacos , Oxidación-Reducción , Ratas Wistar , Espectrometría de Masas en Tándem
10.
BMC Evol Biol ; 14(1): 49, 2014 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-24629134

RESUMEN

BACKGROUND: Because of their fragmented nature, inselberg species are interesting biological models for studying the genetic consequences of disjoint populations. Inselbergs are commonly compared with oceanic islands, as most of them display a marked ecological isolation from the surrounding area. The isolation of these rock outcrops is reflected in the high number of recorded endemic species and the strong floristic differences between individual inselbergs and adjacent habitats. We examined the genetic connectivity of orchids Epidendrum cinnabarinum and E. secundum adapted to Neotropical inselbergs of northeastern Brazil. Our goals were to identify major genetic divergences or disjunctions across the range of the species and to investigate potential demographic and evolutionary mechanisms leading to lineage divergence in Neotropical mountain ecosystems. RESULTS: Based on plastid markers, high genetic differentiation was found for E. cinnabarinum (FST = 0.644) and E. secundum (FST = 0.636). Haplotypes were not geographically structured in either taxon, suggesting that restricted gene flow and genetic drift may be significant factors influencing the diversification of these inselberg populations. Moreover, strong differentiation was found between populations over short spatial scales, indicating substantial periods of isolation among populations. For E. secundum, nuclear markers indicated higher gene flow by pollen than by seeds. CONCLUSIONS: The comparative approach adopted in this study contributed to the elucidation of patterns in both species. Our results confirm the ancient and highly isolated nature of inselberg populations. Both species showed similar patterns of genetic diversity and structure, highlighting the importance of seed-restricted gene flow and genetic drift as drivers of plant diversification in terrestrial islands such as inselbergs.


Asunto(s)
Ecosistema , Orchidaceae/genética , Evolución Biológica , Brasil , Flujo Génico , Flujo Genético , Variación Genética , Orchidaceae/clasificación , Plastidios/genética
11.
Am J Bot ; 101(4): 587-97, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24688055

RESUMEN

PREMISE OF THE STUDY: The term colleter is applied to trichomes or emergences positioned close to developing vegetative and floral meristems that secrete a sticky, mucilaginous, and/or lipophilic exudate. Several ecological functions are attributed to these glands, but none are exclusive to colleters. Patterns of morphology and distribution of colleters may be valuable for systematics and phylogeny, especially concerning problematic and large groups such as the subtribe Pleurothallidinae, and are also essential to understand the evolution of these glands in Orchidaceae as a whole. METHODS: We used scanning electron and light microscopy to examine the structure and occurrence of trichomes on bracts and sepals and in the invaginations of the external ovary wall (IEOW) in flowers in several developmental stages from species in seven genera. KEY RESULTS: The exudate was composed of polysaccharides, lipophilic, and phenolic compounds. Colleters were secretory only during the development of floral organs, except for the glands in the IEOW that were also active in flowers at anthesis. After the secretory phase, fungal hyphae were found penetrating senescent trichomes. CONCLUSIONS: Trichome-like colleters seem to be a widespread character in Epidendroideae, and digitiform colleters are possibly the common type in this subfamily. Mucilage from IEOW colleters may aid in the establishment of symbiotic fungi necessary for seed germination. The presence of colleters in the IEOW may be a case of homeoheterotopy, in which extrafloral nectaries that produce simple sugar-based secretions (as in other orchid species) have changed to glands that produce secretions with complex polysaccharides, as in Pleurothallidinae.


Asunto(s)
Flores/anatomía & histología , Flores/fisiología , Orchidaceae/anatomía & histología , Orchidaceae/fisiología , Flores/crecimiento & desarrollo , Flores/ultraestructura , Meristema/anatomía & histología , Meristema/crecimiento & desarrollo , Meristema/fisiología , Meristema/ultraestructura , Microscopía Electrónica de Rastreo , Orchidaceae/crecimiento & desarrollo , Orchidaceae/ultraestructura , Mucílago de Planta/metabolismo
12.
Clin Orthop Relat Res ; 472(4): 1251-9, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24146360

RESUMEN

BACKGROUND: Subungual exostosis is a relatively common benign bone tumor that occurs in the distal phalanges of the toes and can be a source of pain and nail deformity. There is controversy about the treatment of these lesions and there are few studies that have synthesized what is known and provided meaningful information on treatment. QUESTIONS/PURPOSES: We performed a systematic review to address the following questions: (1) What is the best surgical approach for excising these lesions? (2) What is the age range, sex distribution, and presenting symptoms of subungual exostoses and which toe is most frequently affected? (3) What complications arise from treatment? METHODS: Two authors independently searched multiple databases (Medline, 1950-May 2013; Cochrane EBM database, and EMBASE, 1980-May 2013 provided by OVID; ACP Journal Club, 2003-May 2013; CINAHL by EBSCO, 1937-May 2013; and PubMed by NLM, 1940-May 2013), and key words were chosen to achieve a broad search strategy. We included studies on the management of toe exostoses with > 10 cases and we excluded studies that reported on upper extremity exostoses or osteochondromas. Demographic and treatment data were collected from each article by two independent authors and collated. A total of 124 abstracts were screened, and 116 articles were reviewed in full, of which 13 met the inclusion criteria. RESULTS: Complete marginal excision through a fish mouth incision protecting the nail led to a recurrence rate of 4% and satisfactory clinical results, defined as no requirement for postoperative intervention and a satisfactory clinical appearance in 73%. Most studies provided incomplete descriptions of specific surgical techniques used. Fifty-five percent of the patients were younger than 18 years of age. A history of toe trauma before diagnosis was present in approximately 30% of the cases. Delayed diagnosis occurred in approximately 10% of the cases and onychodystrophy occurred in more than 10%. CONCLUSIONS: There is weak evidence to guide management of subungual exostosis. Adequate wound management postexcision aiming to minimize disruption to the nail bed and matrix may prevent onychodystrophy, which is a common complication of treatment.


Asunto(s)
Neoplasias Óseas , Exostosis , Enfermedades de la Uña , Osteocondroma , Falanges de los Dedos del Pie , Adolescente , Adulto , Distribución por Edad , Neoplasias Óseas/complicaciones , Neoplasias Óseas/diagnóstico , Neoplasias Óseas/cirugía , Exostosis/complicaciones , Exostosis/diagnóstico , Exostosis/cirugía , Femenino , Humanos , Hipertrofia , Masculino , Persona de Mediana Edad , Enfermedades de la Uña/complicaciones , Enfermedades de la Uña/diagnóstico , Enfermedades de la Uña/cirugía , Procedimientos Ortopédicos/efectos adversos , Osteocondroma/complicaciones , Osteocondroma/diagnóstico , Osteocondroma/cirugía , Satisfacción del Paciente , Complicaciones Posoperatorias/etiología , Radiografía , Recurrencia , Distribución por Sexo , Falanges de los Dedos del Pie/diagnóstico por imagen , Falanges de los Dedos del Pie/patología , Falanges de los Dedos del Pie/cirugía , Dedos del Pie , Resultado del Tratamiento , Adulto Joven
13.
Biol Rev Camb Philos Soc ; 99(2): 409-429, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37872698

RESUMEN

Ectotherms that maintain thermal balance in the face of varying climates should be able to colonise a wide range of habitats. In lizards, thermoregulation usually appears as a variety of behaviours that buffer external influences over physiology. Basking species rely on solar radiation to raise body temperatures and usually show high thermoregulatory precision. By contrast, species that do not bask are often constrained by climatic conditions in their habitats, thus having lower thermoregulatory precision. While much focus has been given to the effects of mean habitat temperatures, relatively less is known about how seasonality affects the thermal biology of lizards on a macroecological scale. Considering the current climate crisis, assessing how lizards cope with temporal variations in environmental temperature is essential to understand better how these organisms will fare under climate change. Activity body temperatures (Tb ) represent the internal temperature of an animal measured in nature during its active period (i.e. realised thermal niche), and preferred body temperatures (Tpref ) are those selected by an animal in a laboratory thermal gradient that lacks thermoregulatory costs (i.e. fundamental thermal niche). Both traits form the bulk of thermal ecology research and are often studied in the context of seasonality. In this study, we used a meta-analysis to test how environmental temperature seasonality influences the seasonal variation in the Tb and Tpref of lizards that differ in thermoregulatory strategy (basking versus non-basking). Based on 333 effect sizes from 137 species, we found that Tb varied over a greater magnitude than Tpref across seasons. Variations in Tb were not influenced by environmental temperature seasonality; however, body size and thermoregulatory strategy mediated Tb responses. Specifically, larger species were subjected to greater seasonal variations in Tb , and basking species endured greater seasonal variations in Tb compared to non-basking species. On the other hand, the seasonal variation in Tpref increased with environmental temperature seasonality regardless of body size. Thermoregulatory strategy also influenced Tpref , suggesting that behaviour has an important role in mediating Tpref responses to seasonal variations in the thermal landscape. After controlling for phylogenetic effects, we showed that Tb and Tpref varied significantly across lizard families. Taken together, our results support the notion that the relationship between thermal biology responses and climatic parameters can be taxon and trait dependent. Our results also showcase the importance of considering ecological and behavioural aspects in macroecological studies. We further highlight current systematic, geographical, and knowledge gaps in thermal ecology research. Our work should benefit those who aim to understand more fully how seasonality shapes thermal biology in lizards, ultimately contributing to the goal of elucidating the evolution of temperature-sensitive traits in ectotherms.


Asunto(s)
Lagartos , Humanos , Animales , Lagartos/fisiología , Filogenia , Regulación de la Temperatura Corporal , Temperatura , Biología , Temperatura Corporal
14.
Front Pediatr ; 12: 1357462, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39100648

RESUMEN

Pediatric spine surgery is a high complexity procedure that can carry risks ranging from pain to neurological damage, and even death. This comprehensive mini review explores current best practice obtaining valid and meaningful informed consent (IC) prior to pediatric spinal surgery, including modalities that support effective comprehension and understanding. An evaluation of the literature was performed to explore understanding of surgical IC by patients or their guardians and the role of multimedia tools as a possible facilitator. The evidence discussed throughout this review, based on legal and ethical perspectives, reveals challenges faced by patients and guardians in achieving comprehension and understanding, especially when facing stressful medical situations. In this context, the introduction of multimedia tools emerges as a patient-centered strategy to help improve comprehension and decrease pre-operative uncertainty. This review highlights the need for a tailored approach in obtaining IC for pediatric patients and suggests a potential role of shared decision-making (SDM) in the surgical discussion process.

15.
Ann Med Surg (Lond) ; 86(1): 199-206, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38222761

RESUMEN

Study design: Prospective experimental study. Objective: To compare the accuracy of O-Arm-acquired radiographic and computed tomography (CT) evaluation of thoracic pedicle screw placement with open laminectomy in a simulation laboratory. Summary of background data: Improving surgical safety and procedural efficiency during thoracic posterior spine instrumentation is essential for decreasing complication rates and possible related risks. The most common way of verifying the position of pedicle screws during the surgical procedure and immediately postoperatively is to acquire intraoperative fluoroscopic images and plain radiographs of the spine, respectively. Laboratory simulated surgery is a valuable tool to evaluate the accuracy of those exams. Methods: Twenty simulation models of scoliosis from T3 to T7 were instrumented by five spine fellows (total of 200 pedicle screws), followed by radiographic and CT images acquired with the assistance of the O-Arm which were evaluated by three independent raters. A fellowship-trained spine neurosurgeon performed laminectomies on the instrumented levels and assessed pedicle integrity (gold standard). Results: Forty-eight breaches were identified in the axial direct view after laminectomy. Of those, eighteen breaches were classified as unacceptable. Regarding the sagittal direct view, four breaches were observed, three of which were classified as unacceptable. Overall, both O-arm radiographic and CT evaluations had a significantly high negative predicted value but a low positive predicted value to identify unacceptable breaches, especially in the sagittal plane. The frequency of missed breaches by all three examiners was high, particularly in the sagittal plane. Conclusion: Postoperative evaluation of pedicle screws using O-arm-acquired radiographic or CT images may underdiagnose the presence of breaches. In our study, sagittal breaches were more difficult to diagnose than axial breaches. Although most breaches do not have clinical repercussions, this study suggests that this modality of postoperative radiographic assessment may be inaccurate. Level of evidence: 4.

16.
Cost Eff Resour Alloc ; 11(1): 25, 2013 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-24103591

RESUMEN

BACKGROUND: Chronic hepatitis C affects approximately 170 million people worldwide, and thus being one of the main causes of chronic liver disease. About 20% of patients with chronic hepatitis C will develop cirrhosis over 20 years, and present an increased risk of developing hepatic complications. Sustained virological response (SVR) is associated with a better prognosis compared to untreated patients and treatment failures.The objective of this analysis was to compare treatment costs and outcomes of pegylated interferon-alfa-2a versus pegylated interferon-alfa-2b, both associated with ribavirin, in the therapeutic scheme of 24 weeks and 48 week for hepatitis C genotypes 2/3 and genotype 1, respectively, under the Brazilian Public Health System (SUS) scenario. METHODS: To project disease progression, a Markov model was built based on clinical stages of chronic disease. A Delphi panel was conducted to evaluate medical resources related to each stage, followed by costing of related materials, services, procedures and pharmaceutical products. The evaluation was made from a public payer perspective. The source used for costing was government reimbursement procedures list (SAI/SIH-SUS). Drug acquisition costs were obtained from the Brazilian Official Gazette and "Banco de Preços em Saúde" (government official source). It was assumed a mean patient weight of 70 kg. Costs were reported in 2011 Brazilian Reais (US$1 ≈ $Brz1.80). A systematic review followed by a meta-analysis of the 7 identified randomized controlled trials (RCTs) which compared pegylated interferons, was conducted for obtaining relative efficacy of both drugs: for genotype 2/3, mean rate of SVR was 79.2% for peginterferon-alfa-2a and 73.8% for peginterferon-alfa-2b. For genotype 1, SVR mean rate was 42.09% versus 33.44% (peginterferon-alfa-2a and peginterferon-alfa-2b respectively). Time horizon considered was lifetime. Discount rate for costs and outcomes was 5%, according to Brazilian guidelines for Health Technology Assessment (HTA). RESULTS: Analysis showed that peginterferon-alfa-2a is a dominant therapy compared to peginterferon-alfa-2b for genotype 1 ($Brz 4,345 savings and 0.10 LY/0.25 QALY gains) as well for genotype 2/3 ($Brz 8,001 savings and 0.16 LY/0.39 QALY gains). Projections indicated that for each 1000 patients treated with peginterferon-alfa-2a instead of peginterferon-alfa-2b, the amount of resources saved would be of $Brz 4.3 million for genotypes 2/3 and up to $Brz 8 million for genotype 1. CONCLUSION: These findings suggest that treatment with peginterferon-alfa-2a is more effective and less costly when compared to peginterferon-alfa-2b under SUS perspective in Brazil.

18.
Heliyon ; 9(10): e20517, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37860568

RESUMEN

Neurodevelopment disorders can result in facial dysmorphisms. Therefore, the analysis of facial images using image processing and machine learning techniques can help construct systems for diagnosing genetic syndromes and neurodevelopmental disorders. The systems offer faster and cost-effective alternatives for genotyping tests, particularly when dealing with large-scale applications. However, there are still challenges to overcome to ensure the accuracy and reliability of computer-aided diagnosis systems. This article presents a systematic review of such initiatives, including 55 articles. The main aspects used to develop these diagnostic systems were discussed, namely datasets - availability, type of image, size, ethnicities and syndromes - types of facial features, techniques used for normalization, dimensionality reduction and classification, deep learning, as well as a discussion related to the main gaps, challenges and opportunities.

19.
World Neurosurg X ; 19: 100187, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37026088

RESUMEN

Study design: Retrospective review of multicentric data. Objectives: To estimate the time from initial visit to surgery in adolescent idiopathic scoliosis (AIS) patients and the main reasons for the time to surgery in a multicenter study. Methods: This retrospective study evaluated 509 patients with AIS from 16 hospitals across six Latin American countries. From each hospital's deformity registry, the following patient data were extracted: demographics, main curve Cobb angle, Lenke Classification at the initial visit and time of surgery, time from indication-for-surgery to surgery, curve progression, Risser skeletal-maturity score and causes for surgical cancelation or delay. Surgeons were asked if they needed to change the original surgical plan due to curve progression. Data also were collected on each hospital's waiting list numbers and mean delay to AIS surgery. Results: 66.8% of the patients waited over six months and 33.9% over a year. Waiting time was not impacted by the patient's age when surgery first became indicated (p = 0.22) but waiting time did differ between countries (p < 0.001) and hospitals (p < 0.001). Longer time to surgery was significantly associated with increasing magnitude of the Cobb angle through the second year of waiting (p < 0.001). Reported causes for delay were hospital-related (48.4%), economic (47.3%), and logistic (4.2%). Oddly, waiting time for surgery did not correlate with the hospital's reported waiting-list lengths (p = 0.57). Conclusion: Prolonged waits for AIS surgery are common in Latin America, with rare exceptions. At most centers, patients wait over six months, most commonly for economic and hospital-related reasons. Whether this directly impacts surgical outcomes in Latin America still must be studied.

20.
Arq Gastroenterol ; 60(1): 106-131, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37194769

RESUMEN

Hepatocellular carcinoma (HCC) is the third most common cause of cancer-related mortality worldwide. The Brazilian Society of Hepatology (SBH) published in 2020 the updated recommendations for the diagnosis and treatment of HCC. Since then, new data have emerged in the literature, including new drugs approved for the systemic treatment of HCC that were not available at the time. The SBH board conducted an online single-topic meeting to discuss and review the recommendations on the systemic treatment of HCC. The invited experts were asked to conduct a systematic review of the literature on each topic related to systemic treatment and to present the summary data and recommendations during the meeting. All panelists gathered together for discussion of the topics and elaboration of the updated recommendations. The present document is the final version of the reviewed manuscript containing the recommendations of SBH and its aim is to assist healthcare professionals, policy-makers, and planners in Brazil and Latin America with systemic treatment decision-making of patients with HCC.


Asunto(s)
Carcinoma Hepatocelular , Gastroenterología , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/diagnóstico , Brasil , Sociedades Médicas
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