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1.
Nature ; 600(7888): 259-263, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34853468

RESUMO

Armoured dinosaurs are well known for their evolution of specialized tail weapons-paired tail spikes in stegosaurs and heavy tail clubs in advanced ankylosaurs1. Armoured dinosaurs from southern Gondwana are rare and enigmatic, but probably include the earliest branches of Ankylosauria2-4. Here we describe a mostly complete, semi-articulated skeleton of a small (approximately 2 m) armoured dinosaur from the late Cretaceous period of Magallanes in southernmost Chile, a region that is biogeographically related to West Antarctica5. Stegouros elengassen gen. et sp. nov. evolved a large tail weapon unlike any dinosaur: a flat, frond-like structure formed by seven pairs of laterally projecting osteoderms encasing the distal half of the tail. Stegouros shows ankylosaurian cranial characters, but a largely ancestral postcranial skeleton, with some stegosaur-like characters. Phylogenetic analyses placed Stegouros in Ankylosauria; specifically, it is related to Kunbarrasaurus from Australia6 and Antarctopelta from Antarctica7, forming a clade of Gondwanan ankylosaurs that split earliest from all other ankylosaurs. The large osteoderms and specialized tail vertebrae in Antarctopelta suggest that it had a tail weapon similar to Stegouros. We propose a new clade, the Parankylosauria, to include the first ancestor of Stegouros-but not Ankylosaurus-and all descendants of that ancestor.


Assuntos
Agressão , Dinossauros/anatomia & histologia , Dinossauros/fisiologia , Fósseis , Cauda/anatomia & histologia , Cauda/fisiologia , Animais , Regiões Antárticas , Chile , Comportamento Predatório , Esqueleto
2.
J Exp Zool B Mol Dev Evol ; 338(1-2): 119-128, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-33382212

RESUMO

The adult ankle of early reptiles had five distal tarsal (dt) bones, but in Dinosauria, these were reduced to only two: dt3 and dt4, articulated to metatarsals (mt) mt3 and mt4. Birds have a single distal tarsal ossification center that fuses to the proximal metatarsals to form a new adult skeletal structure: the composite tarsometatarsus. This ossification center develops within a single large embryonic cartilage, but it is unclear if this cartilage results from fusion of earlier cartilages. We studied embryos in species from four different bird orders, an alligatorid, and an iguanid. In all embryos, cartilages dt2, dt3, and dt4 are formed. In the alligatorid and the iguanid, dt2 failed to ossify: only dt3 and dt4 develop into adult bones. In birds, dt2, dt3, and dt4 fuse to form the large distal tarsal cartilage; the ossification center then develops above mt3, in cartilage presumably derived from dt3. During the entire dinosaur-bird transition, a dt2 embryonic cartilage was always formed, as inferred from the embryology of extant birds and crocodilians. We propose that in the evolution of the avian ankle, fusion of cartilages dt3 and dt2 allowed ossification from dt3 to progress into dt2, which began to contribute bone medially, while fusion of dt3 to dt4 enabled the evolutionary loss of the dt4 ossification center. As a result, a single ossification center expands into a plate-like unit covering the proximal ends of the metatarsals, that is key to the development of an integrated tarsometatarsus.


Assuntos
Tornozelo , Evolução Biológica , Animais , Tornozelo/anatomia & histologia , Aves/anatomia & histologia , Dinossauros/anatomia & histologia , Ossos do Metatarso
3.
Eur J Epidemiol ; 36(11): 1097-1101, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34279730

RESUMO

Non-inferiority trials are used to test if a novel intervention is not worse than a standard treatment by more than a prespecified amount, the non-inferiority margin (ΔNI). The ΔNI indicates the amount of efficacy loss in the primary outcome that is acceptable in exchange for non-efficacy benefits in other outcomes. However, non-inferiority designs are sometimes used when non-efficacy benefits are absent. Without non-efficacy benefits, loss in efficacy cannot be easily justified. Further, non-efficacy benefits are scarcely defined or considered by trialists when determining the magnitude of and providing justification for the non-inferiority margin. This is problematic as the importance of a treatment's non-efficacy benefits are critical to understanding the results of a non-inferiority study. Here we propose the routine reporting in non-inferiority trial protocols and publications of non-efficacy benefits of the novel intervention along with the reporting of non-inferiority margins and their justification. The justification should include the specific trade-off between the accepted loss in efficacy (ΔNI) and the non-efficacy benefits of the novel treatment and should describe whether patients and other relevant stakeholders were involved in the definition of the ΔNI.

4.
Can J Surg ; 64(1): E69-E75, 2021 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-33560737

RESUMO

Background: There has been an increase in opioid usage and opioid-related deaths. Opioids prescribed to surgical patients have similarly increased. The aim of this study was to assess opioid consumption in patients undergoing laparoscopic appendectomy (LA) and laparoscopic cholecystectomy (LC) and to determine whether a standardized prescription could affect opioid consumption without affecting patient satisfaction. Methods: Patients undergoing LA or LC were recruited prospectively during 2 time periods (April to June 2017 and November 2017 to January 2018). In the first phase, surgeons continued their usual postoperative analgesia prescribing patterns. In the second phase, a standardized prescription was implemented. Patients were contacted by telephone and a questionnaire was completed for both phases of the study. The primary outcome was the quantity of opioids prescribed and consumed. Results: In the first phase, 166 patients who underwent LC or LA were recruited. The median number of prescribed opioid tablets was 20 and the median number consumed was 2. Ninety-five percent of patients reported satisfaction with their analgesia. Based on these results, a standardized prescription for multimodal analgesia was implemented for the second phase, consisting of 10 opioid tablets. In the second phase, 129 patients who underwent LA or LC were recruited. There was a significant decrease in the median number of opioid pills filled (10) and consumed (0), with no difference in reported satisfaction with analgesia. Conclusion: Patients are prescribed an excess of opioids after LA or LC. Implementation of a standardized prescription based on a quality improvement intervention was effective at decreasing the number of opioids prescribed and consumed.


Contexte: On a observé une augmentation de la consommation d'opioïdes, ainsi qu'une hausse des décès associés à ces substances. On a aussi constaté une augmentation semblable dans la prescription d'opioïdes aux patients ayant subi une chirurgie. La présente étude visait à évaluer la consommation d'opioïdes chez les personnes ayant subi une appendicectomie par laparoscopie (AL) ou une cholécystectomie par laparoscopie (CL), de même qu'à déterminer si une ordonnance normalisée pouvait modifier la consommation d'opioïdes sans nuire à la satisfaction des patients. Méthodes: Des patients devant subir une AL ou une CL ont été recrutés de façon prospective entre avril et juin 2017 et entre novembre 2017 et janvier 2018. Durant la première phase de l'étude, les chirurgiens ont maintenu leurs habitudes de prescription d'analgésie postopératoire. Durant la deuxième phase, toutefois, ils devaient avoir recours à une ordonnance normalisée. Dans les 2 phases de l'étude, les patients ont été joints par téléphone et un questionnaire a été rempli. Le principal résultat à l'étude était la quantité d'opioïdes prescrits et consommés. Résultats: Pour la première phase de l'étude, 166 patients ont été recrutés. Les nombres médians de comprimés prescrits et consommés étaient de 20 et de 2, respectivement. De tous les patients, 95 % se sont dits satisfaits de leur analgésie. Pour la deuxième phase, une ordonnance normalisée d'analgésie multimodale, qui comptait 10 comprimés, a été mise en place, et 129 patients ont été recrutés. On a alors observé une diminution significative du nombre médian de comprimés remis (10) et consommés (0), et aucune différence quant au degré de satisfaction déclaré. Conclusion: Les patients se voient prescrire trop d'opioïdes après une AL ou une CL. La création d'une ordonnance normalisée dans le cadre d'une intervention d'amélioration de la qualité a réduit efficacement le nombre de comprimés d'opioïdes prescrits et consommés.


Assuntos
Analgésicos Opioides/uso terapêutico , Apendicectomia/métodos , Colecistectomia Laparoscópica , Prescrições de Medicamentos/estatística & dados numéricos , Prescrições de Medicamentos/normas , Uso de Medicamentos/estatística & dados numéricos , Laparoscopia , Dor Pós-Operatória/tratamento farmacológico , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
5.
Breast Cancer Res Treat ; 182(2): 429-438, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32449079

RESUMO

PURPOSE: Although there has been a significant increase in the use of oncoplastic surgery (OPS), data on the postoperative safety of this approach are limited compared to traditional lumpectomy. This study aimed to compare the immediate (30-day) postoperative complications associated with OPS and traditional lumpectomy. METHODS: An analysis of the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) database was performed on women with breast cancer who underwent OPS or traditional lumpectomy. Logistic regression was used to explore the effect of type of surgery on the outcome of interest. RESULTS: A total of 109,487 women were analyzed of whom 8.3% underwent OPS. OPS had a longer median operative time than traditional lumpectomy. The unadjusted immediate (30-day) overall complication rate was significantly higher with OPS than traditional lumpectomy (3.8% versus 2.6%, p < 0.001). After adjusting for baseline differences, overall 30-day postoperative complications were significantly higher amongst women undergoing OPS compared with traditional lumpectomy (OR 1.41, 95%CI 1.24-1.59). Factors that were independent predictors of overall 30-day complications included higher age, higher BMI, race, smoking status, lymph node surgery, neoadjuvant chemotherapy, ASA class ≥ 3, in situ disease, and year of operation. The interaction term between type of surgery and operative time was not statistically significant, indicating that operative time did not modify the effect of type of surgery on immediate postoperative complications. CONCLUSIONS: Although there were slightly higher overall complication rates with OPS, the absolute rates remained quite low for both groups. Therefore, OPS may be performed in women with breast cancer who are suitable candidates.


Assuntos
Neoplasias da Mama/cirurgia , Carga Global da Doença/estatística & dados numéricos , Mamoplastia/efeitos adversos , Mastectomia Segmentar/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Idoso , Mama/patologia , Mama/cirurgia , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Bases de Dados Factuais/estatística & dados numéricos , Estudos de Viabilidade , Feminino , Mortalidade Hospitalar , Humanos , Mamoplastia/métodos , Mastectomia Segmentar/métodos , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle , Melhoria de Qualidade/estatística & dados numéricos , Estudos Retrospectivos , Resultado do Tratamento
6.
Ann Surg Oncol ; 27(8): 2664-2676, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32020394

RESUMO

PURPOSE: Several randomized controlled trials (RCTs) have investigated observation or axillary radiotherapy (ART) in place of completion axillary lymph node dissection (cALND) for management of positive sentinel nodes (SNs) in clinically node-negative women with breast cancer. The optimal treatment strategy for this population is not known. METHODS: MEDLINE, Embase, and EBM Reviews-NHS Economic Evaluation Database were searched from inception until July 2019. A systematic review and narrative summary was performed of RCTs comparing observation or ART versus cALND in clinically node-negative female breast cancer patients with positive SNs. The Cochrane risk of bias tool for RCTs was used to assess risk of bias. Outcomes of interest included overall survival (OS), disease-free survival (DFS), axillary recurrence, and axillary surgery-related morbidity. RESULTS: Three trials compared observation with cALND, and two trials compared ART with cALND. No studies blinded participants or personnel, and there was heterogeneity in inclusion criteria, study design, and follow-up. Neither observation nor ART resulted in statistically inferior 5- or 8-year OS or DFS compared with cALND. There was also no statistically significant increase in axillary recurrences associated with either approach. Four trials reported morbidity outcomes, and all showed cALND was associated with significantly more lymphedema, paresthesia, and shoulder dysfunction compared with observation or ART. CONCLUSIONS: Women with clinically node-negative breast cancer and positive SNs can safely be managed without cALND.


Assuntos
Neoplasias da Mama , Linfonodo Sentinela , Conduta Expectante , Axila , Neoplasias da Mama/patologia , Neoplasias da Mama/radioterapia , Neoplasias da Mama/cirurgia , Feminino , Humanos , Excisão de Linfonodo , Linfonodos/cirurgia , Metástase Linfática , Ensaios Clínicos Controlados Aleatórios como Assunto , Linfonodo Sentinela/cirurgia , Biópsia de Linfonodo Sentinela
7.
Gastrointest Endosc ; 91(5): 1015-1026.e7, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31926966

RESUMO

BACKGROUND AND AIMS: Propofol is increasingly being used for sedation in colonoscopy; however, its benefits over midazolam (± short-acting opioids) are not well quantified. The objective of this study was to compare safety, satisfaction, and efficiency outcomes of propofol versus midazolam (± short-acting opioids) in patients undergoing colonoscopy. METHODS: We systematically searched Medline, Embase, and the Cochrane library (to July 30, 2018) for randomized controlled trials of colonoscopies performed with propofol versus midazolam (± short-acting opioids). We pooled odds ratios for cardiorespiratory outcomes using mixed-effects conditional logistic models. We pooled standardized mean differences (SMDs) for patient and endoscopist satisfaction and efficiency outcomes using random-effects models. RESULTS: Nine studies of 1427 patients met the inclusion criteria. There were no significant differences in cardiorespiratory outcomes (hypotension, hypoxia, bradycardia) between sedative groups. Patient satisfaction was high in both groups, with most patients reporting willingness to undergo a future colonoscopy with the same sedative regimen. In the meta-analysis, patients sedated with propofol had greater satisfaction than those sedated with midazolam (± short-acting opioids) (SMD, .54; 95% confidence interval [CI], .30-.79); however, there was considerable heterogeneity. Procedure time was similar between groups (SMD, .15; 95% CI, .04-.27), but recovery time was shorter in the propofol group (SMD, .41; 95% CI, .08-.74). The median difference in recovery time was 3 minutes, 6 seconds shorter in patients sedated with propofol. CONCLUSIONS: Both propofol and midazolam (± short-acting opioids) result in high patient satisfaction and appear to be safe for use in colonoscopy. The marginal benefits to propofol are small improvements in satisfaction and recovery time.


Assuntos
Midazolam/uso terapêutico , Propofol/uso terapêutico , Analgésicos Opioides , Colonoscopia , Sedação Consciente , Humanos , Hipnóticos e Sedativos , Satisfação do Paciente , Satisfação Pessoal , Resultado do Tratamento
8.
Dis Colon Rectum ; 63(8): 1108-1117, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32229781

RESUMO

BACKGROUND: Operative approaches for Hinchey III diverticulitis include the Hartmann procedure, primary resection and anastomosis, and laparoscopic lavage. Several randomized controlled trials and meta-analyses have compared these approaches; however, results are conflicting and previous studies have not captured the complexity of balancing surgical risks and quality of life. OBJECTIVE: This study aimed to determine the optimal operative strategy for patients with Hinchey III sigmoid diverticulitis. DESIGN: We developed a Markov cohort model, incorporating perioperative morbidity/mortality, emergency and elective reoperations, and quality-of-life weights. We derived model parameters from systematic reviews and meta-analyses, where possible. We performed a second-order Monte Carlo probabilistic sensitivity analysis to account for joint uncertainty in model parameters. SETTING: This study measured outcomes over patients' lifetime horizon. PATIENTS: The base case was a simulated cohort of 65-year-old patients with Hinchey III diverticulitis. A scenario simulating a cohort of highly comorbid 80-year-old patients was also planned. INTERVENTIONS: Hartmann procedure, primary resection and anastomosis (with or without diverting ileostomy), and laparoscopic lavage were performed. MAIN OUTCOME MEASURES: Quality-adjusted life years were the primary outcome measured. RESULTS: Following surgery for Hinchey III diverticulitis, 39.5% of patients who underwent the Hartmann procedure, 14.3% of patients who underwent laparoscopic lavage, and 16.7% of patients who underwent primary resection and anastomosis had a stoma at 12 months. After applying quality-of-life weights, primary resection and anastomosis was the optimal operative strategy, yielding 18.0 quality-adjusted life years; laparoscopic lavage and the Hartmann procedure yielded 9.6 and 13.7 fewer quality-adjusted life months. A scenario analysis for elderly, highly comorbid patients could not be performed because of a lack of high-quality evidence to inform model parameters. LIMITATIONS: This model required assumptions about the long-term postoperative course of patients who underwent laparoscopic lavage because few long-term data for this group have been published. CONCLUSIONS: Although the Hartmann procedure is widely used for Hinchey III diverticulitis, when considering both surgical risks and quality of life, both laparoscopic lavage and primary resection and anastomosis provide greater quality-adjusted life years for patients with Hinchey III diverticulitis, and primary resection and anastomosis appears to be the optimal approach. See Video Abstract at http://links.lww.com/DCR/B223. ESTRATEGIA OPERATIVA ÓPTIMA EN DIVERTICULITIS HINCHEY III DE SIGMOIDES: UN ANÁLISIS DE DECISION: Los enfoques quirúrgicos para la diverticulitis Hinchey III incluyen el procedimiento de Hartmann, la resección primaria y anastomosis, y el lavado laparoscópico. Varios ensayos controlados aleatorios y metanálisis han comparado estos enfoques; sin embargo, los resultados son contradictorios y los estudios previos no han captado la complejidad de equilibrar los riesgos quirúrgicos y la calidad de vida.Determinar la estrategia operativa óptima para pacientes con diverticulitis Hinchey III de sigmoides.Desarrollamos un modelo de cohorte de Markov, incorporando morbilidad / mortalidad perioperatoria, reoperaciones electivas y de emergencia, y pesos de calidad de vida. Derivamos los parámetros del modelo de revisiones sistemáticas y metaanálisis, cuando fue posible. Realizamos un análisis de sensibilidad probabilístico Monte Carlo de segundo orden para tener en cuenta la incertidumbre conjunta en los parámetros del modelo.Seguimiento de por vida.El caso base fue una cohorte simulada de pacientes de 65 años con diverticulitis de Hinchey III. También se planeó un escenario que simulaba una cohorte de pacientes de 80 años altamente comórbidos.Procedimiento de Hartmann, resección primaria y anastomosis (con o sin desviación de ileostomía) y lavado laparoscópico.Años de vida ajustados por calidad.Después de la cirugía para la diverticulitis de Hinchey III, el 39.5% de los pacientes que se sometieron al procedimiento de Hartmann, el 14.3% de los pacientes que se sometieron a un lavado laparoscópico, y el 16.7% de los pacientes que se sometieron a resección primaria y anastomosis tuvieron un estoma a los 12 meses. Después de aplicar el peso de la calidad de vida, la resección primaria y la anastomosis fueron la estrategia operativa óptima, que dio como resultado 18.0 años de vida ajustados en función de la calidad; el lavado laparoscópico y el procedimiento de Hartmann arrojaron 9.6 y 13.7 meses de vida ajustados en función de la calidad, respectivamente. No se pudo realizar un análisis de escenarios para pacientes de edad avanzada altamente comórbidos debido a la falta de evidencia de alta calidad para informar los parámetros del modelo.Este modelo requirió suposiciones sobre el curso postoperatorio a largo plazo de pacientes que se sometieron a lavado laparoscópico, ya que se han publicado pocos datos a largo plazo para este grupo.Aunque el procedimiento de Hartmann se usa ampliamente para la diverticulitis de Hinchey III, cuando se consideran tanto los riesgos quirúrgicos como la calidad de vida, tanto el lavado laparoscópico como la resección primaria y la anastomosis proporcionan una mayor calidad de años de vida ajustada para los pacientes con diverticulitis de Hinchey III y la resección primaria y anastomosis parece ser el enfoque óptimo. Consulte Video Resumen en http://links.lww.com/DCR/B223.


Assuntos
Anastomose Cirúrgica/estatística & dados numéricos , Diverticulite/cirurgia , Laparoscopia/estatística & dados numéricos , Doenças do Colo Sigmoide/patologia , Idoso , Idoso de 80 Anos ou mais , Anastomose Cirúrgica/métodos , Técnicas de Apoio para a Decisão , Diverticulite/classificação , Diverticulite/psicologia , Procedimentos Cirúrgicos Eletivos/métodos , Humanos , Laparoscopia/métodos , Metanálise como Assunto , Período Perioperatório/mortalidade , Lavagem Peritoneal/métodos , Período Pós-Operatório , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Reoperação/estatística & dados numéricos , Medição de Risco
9.
Ann Surg ; 269(5): 849-855, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30339624

RESUMO

OBJECTIVE: To determine whether laparoscopic surgery is noninferior to open surgery for rectal cancer in terms of quality of surgical resection outcomes. BACKGROUND: Randomized clinical trials (RCTs) have evaluated the oncologic safety of laparoscopic versus open surgery for rectal cancer with conflicting results. Prior meta-analyses comparing these operative approaches in terms of quality of surgical resection aimed to demonstrate if one approach was superior. However, this method is not appropriate and potentially misleading when noninferiority RCTs are included. METHODS: MEDLINE, EMBASE, and Cochrane were searched to identify RCTs comparing these operative approaches. Risk differences (RDs) were pooled using random-effects meta-analyses. One-sided Z tests were used to determine noninferiority. Noninferiority margins (ΔNI) for circumferential resection margin (CRM), plane of mesorectal excision (PME), distal resection margin (DRM), and a composite outcome ("successful resection") were based on the consensus of 58 worldwide experts. RESULTS: Fourteen RCTs were included. Laparoscopic resection was noninferior compared with open resection for the rate of positive CRM [RD 0.79%, 90% confidence interval (CI) -0.46 to 2.04, ΔNI = 2.33%, PNI = 0.026], incomplete PME (RD 1.16%, 90% CI -0.27 to 2.59, ΔNI = 2.85%, PNI = 0.025), and positive DRM (RD 0.15%, 90% CI -0.58 to 0.87, ΔNI = 1.28%, PNI = 0.005). For the rate of "successful resection" (RD 6.16%, 90% CI 2.30-10.02), the comparison was inconclusive when using the ΔNI generated by experts (ΔNI = 2.71%, PNI = 0.07), although no consensus was achieved for this ΔNI. CONCLUSIONS: Laparoscopy was noninferior to open surgery for rectal cancer in terms of individual quality of surgical resection outcomes. These findings are concordant with RCTs demonstrating noninferiority for long-term oncologic outcomes between the 2 approaches.


Assuntos
Laparoscopia , Neoplasias Retais/cirurgia , Procedimentos Cirúrgicos do Sistema Digestório/métodos , Procedimentos Cirúrgicos do Sistema Digestório/normas , Humanos , Qualidade da Assistência à Saúde , Resultado do Tratamento
10.
Front Zool ; 16: 44, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31827570

RESUMO

BACKGROUND: The origin of birds is marked by a significant decrease in body size along with an increase in relative forelimb size. However, before the evolution of flight, both traits may have already been related: It has been proposed that an evolutionary trend of negative forelimb allometry existed in non-avian Theropoda, such that larger species often have relatively shorter forelimbs. Nevertheless, several exceptions exist, calling for rigorous phylogenetic statistical testing. RESULTS: Here, we re-assessed allometric patterns in the evolution of non-avian theropods, for the first time taking into account the non-independence among related species due to shared evolutionary history.We confirmed a main evolutionary trend of negative forelimb allometry for non-avian Theropoda, but also found support that some specific subclades (Coelophysoidea, Ornithomimosauria, and Oviraptorosauria) exhibit allometric trends that are closer to isometry, losing the ancestral negative forelimb allometry present in Theropoda as a whole. CONCLUSIONS: Explanations for negative forelimb allometry in the evolution of non-avian theropods have not been discussed, yet evolutionary allometric trends often reflect ontogenetic allometries, which suggests negative allometry of the forelimb in the ontogeny of most non-avian theropods. In modern birds, allometric growth of the limbs is related to locomotor and behavioral changes along ontogeny. After reviewing the evidence for such changes during the ontogeny of non-avian dinosaurs, we propose that proportionally longer arms of juveniles became adult traits in the small-sized and paedomorphic Aves.

11.
Am J Obstet Gynecol ; 221(5): 410-428.e19, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31082383

RESUMO

OBJECTIVE DATA: Robotic assistance may facilitate completion of minimally invasive hysterectomy, which is the standard of care for the treatment of early-stage endometrial cancer, in patients for whom conventional laparoscopy is challenging. The aim of this systematic review was to assess conversion to laparotomy and perioperative complications after laparoscopic and robotic hysterectomy in patients with endometrial cancer and obesity (body mass index, ≥30 kg/m2). STUDY: We systematically searched MEDLINE, EMBASE, and Evidence-Based Medicine Reviews (January 1, 2000, to July 18, 2018) for studies of patients with endometrial cancer and obesity (body mass index, ≥30 kg/m2) who underwent primary hysterectomy. STUDY APPRAISAL AND SYNTHESIS METHODS: We determined the pooled proportions of conversion, organ/vessel injury, venous thromboembolism, and blood transfusion. We assessed risk of bias with the Institute of Health Economics Quality Appraisal Checklist for single-arm studies, and Newcastle-Ottawa Quality Scale for double-arm studies. RESULTS: We identified 51 observational studies that reported on 10,800 patients with endometrial cancer and obesity (study-level body mass index, 31.0-56.3 kg/m2). The pooled proportions of conversion from laparoscopic and robotic hysterectomy were 6.5% (95% confidence interval, 4.3-9.9) and 5.5% (95% confidence interval, 3.3-9.1), respectively, among patients with a body mass index of ≥30 kg/m2, and 7.0% (95% confidence interval, 3.2-14.5) and 3.8% (95% confidence interval, 1.4-9.9) among patients with body mass index of ≥40 kg/m2. Inadequate exposure because of adhesions/visceral adiposity was the most common reason for conversion for both laparoscopic (32%) and robotic hysterectomy (61%); however, intolerance of the Trendelenburg position caused 31% of laparoscopic conversions and 6% of robotic hysterectomy conversions. The pooled proportions of organ/vessel injury (laparoscopic, 3.5% [95% confidence interval, 2.2-5.5]; robotic hysterectomy, 1.2% [95% confidence interval, 0.4-3.4]), venous thromboembolism (laparoscopic, 0.5% [95% confidence interval, 0.2-1.2]; robotic hysterectomy, 0.5% [95% confidence interval, 0.1-2.0]), and blood transfusion (laparoscopic, 2.8% [95% confidence interval, 1.5-5.1]; robotic hysterectomy, 2.1% [95% confidence interval, 1.6-3.8]) were low and not appreciably different between arms. CONCLUSION: Robotic and laparoscopic hysterectomy have similar rates perioperative complications in patients with endometrial cancer and obesity, but robotic hysterectomy may reduce conversions because of positional intolerance in patients with morbid obesity. Existing literature is limited by selection and confounding bias, and randomized trials are needed to inform practice standards in this population.


Assuntos
Neoplasias do Endométrio/cirurgia , Histerectomia , Laparoscopia , Obesidade/complicações , Procedimentos Cirúrgicos Robóticos , Transfusão de Sangue , Índice de Massa Corporal , Conversão para Cirurgia Aberta , Neoplasias do Endométrio/complicações , Feminino , Humanos , Gordura Intra-Abdominal , Posicionamento do Paciente/efeitos adversos , Complicações Pós-Operatórias , Aderências Teciduais/complicações , Lesões do Sistema Vascular , Tromboembolia Venosa
12.
Can J Surg ; 62(6): 426-435, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31782298

RESUMO

Background: The use of prophylactic mesh in end colostomy procedures has been shown to reduce the rate of parastomal hernia. However, the degree to which the practice has been adopted clinically remains unknown. We conducted a study to evaluate the current opinions and practice patterns of Canadian and US colorectal surgeons with regard to the use of prophylactic mesh in end colostomy. Methods: Between May and July 2017, we conducted an internet-based survey of colorectal surgeons in Canada and the United States (selected at random). Using a questionnaire designed and tested for this study, we assessed the rate of mesh use, types of mesh and placement techniques, and perceived barriers and facilitators associated with the practice. Results: Forty-eight (51.6%) of 93 invited Canadian surgeons and 253 (16.6%) of 1521 invited US surgeons responded (overall response rate 18.6%). Of the 301 respondents, 32 (10.6%) were currently using mesh, 32 (10.6%) had previously used mesh, and 237 (78.7%) had never used mesh. Of 29 respondents currently using mesh, 12 (41.4%) used it only in selected patients; the majority used a sublay technique (20 [69.0%]) and biologic mesh (17 [58.6%]). Most respondents agreed that parastomal hernias are common and negatively affect quality of life; however, there remained concerns about evidence quality and the perceived risk associated with mesh among those who had never or had previously used mesh. Conclusion: Prophylactic mesh placement remains relatively uncommon; when used, biologic mesh was the most common type. Many surgeons were not convinced of the safety or efficacy of prophylactic mesh placement.


Contexte: Il a été démontré que la pose d'un treillis prophylactique durant une colostomie terminale réduit le risque de hernie parastomale. On ignore toutefois à quel point cette pratique a été adoptée en contexte clinique. Nous avons mené une étude pour connaître l'opinion et les habitudes des chirurgiens colorectaux canadiens et américains quant à cette intervention. Méthodes: De mai à juillet 2017, nous avons mené un sondage en ligne auprès de chirurgiens colorectaux canadiens et américains sélectionnés aléatoirement. À l'aide d'un questionnaire conçu et validé pour cette étude, nous avons évalué le taux de pose de treillis, le type de treillis et la technique utilisé, ainsi que les facteurs facilitant ou limitant l'intervention. Résultats: Au total, 48 des 93 chirurgiens canadiens (51,6 %) et 253 des 1521 chirurgiens américains (16,6 %) approchés ont répondu au sondage (taux de réponse global : 18,6 %). Sur les 301 répondants, 32 (10,6 %) ont dit qu'ils installent actuellement des treillis, 32 (10,6 %) ont dit en avoir installé, et 237 (78,7 %) ont dit n'en avoir jamais installé. Parmi 29 répondants posant actuellement des treillis, 12 (41,4 %) ont déclaré y avoir recours pour certains patients seulement; la majorité pose les treillis dans l'espace prépéritonéal (20 [69,0 %]) et se sert de treillis biologiques (17 [58,6 %]). La plupart des répondants s'entendaient pour dire que les hernies parastomales sont courantes et ont des répercussions négatives sur la qualité de vie des patients; cependant, les chirurgiens n'ayant jamais installé de treillis ou en ayant seulement installé par le passé se sont dits préoccupés par la qualité des données et les risques perçus associés aux treillis. Conclusion: La pose d'un treillis à des fins prophylactiques demeure relativement rare. Les treillis biologiques étaient les plus fréquemment utilisés par les répondants. Bon nombre des chirurgiens questionnés n'étaient pas convaincus de l'innocuité ou de l'efficacité de l'intervention.


Assuntos
Colostomia/efeitos adversos , Hérnia Ventral/prevenção & controle , Hérnia Incisional/prevenção & controle , Complicações Pós-Operatórias/prevenção & controle , Padrões de Prática Médica , Telas Cirúrgicas , Atitude do Pessoal de Saúde , Canadá , Colostomia/instrumentação , Hérnia Ventral/etiologia , Humanos , Hérnia Incisional/etiologia , Seleção de Pacientes , Complicações Pós-Operatórias/etiologia , Estados Unidos
13.
Ann Surg ; 267(4): 646-655, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-28654540

RESUMO

OBJECTIVE: To review the literature on chest wall resection for recurrent breast cancer and evaluate overall survival (OS) and quality-of-life (QOL) outcomes. BACKGROUND: Full-thickness chest wall resection for recurrent breast cancer is controversial, as historically these recurrences have been thought of as a harbinger of systemic disease. METHODS: A systematic search in MEDLINE, EMBASE, and Cochrane CENTRAL identified 48 eligible studies, all retrospective, accounting for 1305 patients. The review is reported following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Primary end points were patient-centered QOL outcomes and OS; secondary outcomes included disease-free survival (DFS) and 30-day morbidity. Risk of bias was assessed using the Methodological Index for Non-Randomized Studies instrument and the Oxford Centre for Evidence-Based Medicine's levels of evidence tool. Random-effects meta-analysis was used to create pooled estimates. Meta-regressions and sensitivity analyses were used to explore study heterogeneity by age, year of publication, risk of bias, and surgical intent (curative vs palliative). RESULTS: Studies consistently reported excellent OS and DFS in properly selected patients. Pooled estimates for 5-year OS in all studies and those from the past 15 years were 40.8% [95% confidence interval (CI) 35.2-46.7) and 43.1% (95% CI 35.8-50.7), whereas pooled 5-year DFS was 27.1% (95% CI 16.6-41.0). Eight studies reported excellent outcomes related to QOL. Mortality was consistently low (<1%) and 30-day pooled morbidity was 20.2% (95% CI 15.3%-26.3%). Study quality varied, and risk of selection bias in included studies was high. CONCLUSIONS: Full-thickness chest wall resection can be performed with excellent survival and low morbidity. Few studies report on QOL; prospective studies should focus on patient-centered outcomes in this population.


Assuntos
Neoplasias da Mama/cirurgia , Recidiva Local de Neoplasia/cirurgia , Parede Torácica/cirurgia , Neoplasias da Mama/patologia , Intervalo Livre de Doença , Humanos , Invasividade Neoplásica , Recidiva Local de Neoplasia/patologia , Avaliação de Resultados da Assistência ao Paciente , Complicações Pós-Operatórias , Qualidade de Vida , Fatores de Risco , Análise de Sobrevida , Parede Torácica/patologia
14.
Ann Surg ; 267(6): 1056-1062, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29215370

RESUMO

BACKGROUND: Over the past 2 decades, there has been an increase in opioid use and subsequently, opioid deaths. The amount of opioid prescribed to surgical patients has also increased. The aim of this systematic review was to determine postdischarge opioid consumption in surgical patients compared with the amount of opioid prescribed. Secondary outcomes included adequacy of pain control and disposal methods for unused opioids. OBJECTIVE: The objective of this study is to characterize postdischarge opioid consumption and prescription patterns in surgical patients. METHODS: A systematic search in MEDLINE and EMBASE identified 11 patient survey studies reporting on postdischarge opioid use in 3525 surgical patients. RESULTS: The studies reported on a variety of surgical operations, including abdominal surgery, orthopedic procedures, tooth extraction, and dermatologic procedures. The majority of patients consumed 15 pills or less postdischarge. The proportion of used opioids ranged from 5.6% to 59.1%, with an outlier of 90.1% in pediatric spinal fusion patients. Measured pain scores of those taking opioids ranged between 2 and 5 out of 10 and the majority of patients were satisfied with their pain control. Seventy percent of patients kept the excess opioids. Where planned disposal methods were reported, between 4% and 59% of patients planned proper disposal. CONCLUSION: This study suggests that surgical patients are using substantially less opioid than prescribed. There is a lack of awareness regarding proper disposal of leftover medication, leaving excess opioid that may be used inappropriately by the patient or others. Education for providers and clinical practice guidelines that provide guidance on prescription of outpatient of opioids are required.


Assuntos
Analgésicos Opioides/uso terapêutico , Prescrições de Medicamentos/estatística & dados numéricos , Dor Pós-Operatória/tratamento farmacológico , Alta do Paciente , Padrões de Prática Médica , Armazenamento de Medicamentos/métodos , Humanos , Manejo da Dor
15.
Breast Cancer Res Treat ; 170(2): 373-379, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29546481

RESUMO

PURPOSE: Postoperative complication rates for elderly women undergoing breast cancer surgery have not been well studied. We describe the postoperative complication rates of elderly (≥ 70 years) women with breast cancer and compare them with young (40-69 years) women. METHODS: Data were extracted from the National Surgical Quality Improvement Program database (2004-2014). We included women with invasive breast cancer who underwent surgery. Outcomes were 30-day postoperative morbidity and mortality (complications), which were compared between young and elderly women. Morbidity was categorized using the Surgical Risk Preoperative Assessment System (SURPAS) clusters. RESULTS: We identified 100,037 women of which 26.7% were elderly. Compared to young women, elderly women were more likely to have more comorbidities and undergo breast-conserving surgery, but less likely to undergo lymph node surgery, breast reconstruction, and neoadjuvant chemotherapy. While the 30-day overall morbidity rate was not significantly different between young and elderly women (3.9 vs. 3.8%, p = 0.2), elderly women did have significantly higher rates of pulmonary, cardiac (arrest and myocardial infarction), venous thromboembolic, and neurological morbidity. Specific morbidities that showed significantly lower rates among elderly women included wound disruption and deep and organ space surgical site infection. Any cause death was significantly higher in elderly compared to young women (0.2 vs. 0.05%, p < 0.001). CONCLUSIONS: While some specific 30-day postoperative morbidities were more often seen in elderly women, the overall 30-day postoperative complication rate was very low. These data support the safety of breast cancer surgery in well-selected elderly patients.


Assuntos
Neoplasias da Mama/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/mortalidade , Neoplasias da Mama/cirurgia , Comorbidade , Bases de Dados Factuais , Feminino , Humanos , Pessoa de Meia-Idade , Morbidade , Mortalidade , Complicações Pós-Operatórias , Período Pós-Operatório , Estudos Retrospectivos
16.
Ann Surg Oncol ; 25(11): 3171-3178, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30051366

RESUMO

INTRODUCTION: Quality of surgical resection metrics (QSRMs) have been used as surrogates for long-term oncologic outcomes in non-inferiority randomized clinical trials (RCTs) comparing laparoscopic and open surgery for rectal cancer. However, non-inferiority margins (ΔNI) for QSRMs have not been previously defined. METHODS: A two-round, web-based Delphi was used to define ΔNI for four QSRMs: positive circumferential resection margin (CRM), incomplete plane of mesorectal excision (PME), positive distal resection margin (DRM), and a composite of these outcomes. Overall, 130 international experts in rectal cancer (68 surgeons, 20 medical oncologists, 16 radiation oncologists, and 26 pathologists) were invited to participate. Experts were presented with evidence syntheses summarizing the association between QSRMs and long-term outcomes, and pooled quality of surgical resection outcomes for open surgery, and were asked to provide ΔNI for all outcomes balancing the risks and benefits of minimally invasive surgery. RESULTS: Seventy-two experts participated: 57 completed the initial questionnaire and 58 completed the revised questionnaire, with 43 participating in both rounds. Consensus was reached for all individual QSRM ΔNI but not for the composite. The mean (standard deviation) ΔNI was an absolute difference of 2.33% (1.59%) for the proportion of positive CRMs when comparing surgical interventions for the treatment of rectal cancer: 2.85% (1.83%) for incomplete PME; 1.28% (1.13%) for positive DRMs; and 2.71% (2.28%) for the composite. However, opinions varied widely for the composite outcome. CONCLUSIONS: Web-based Delphi processes are a feasible approach to generate ΔNI to evaluate novel surgical interventions. The generated ΔNI for QSRMs for rectal cancer can be used for future RCTs and non-inferiority meta-analyses.


Assuntos
Procedimentos Cirúrgicos do Sistema Digestório/métodos , Laparoscopia , Complicações Pós-Operatórias , Melhoria de Qualidade , Neoplasias Retais/patologia , Neoplasias Retais/cirurgia , Consenso , Estudos de Equivalência como Asunto , Seguimentos , Humanos , Margens de Excisão , Indicadores de Qualidade em Assistência à Saúde , Resultado do Tratamento
17.
Dis Colon Rectum ; 61(12): 1442-1453, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30371549

RESUMO

BACKGROUND: The traditional approach for perforated diverticulitis, the Hartmann procedure, has considerable morbidity and the challenge of stoma reversal. Alternative procedures, including primary resection and anastomosis and laparoscopic lavage, have been proposed but remain controversial. OBJECTIVE: The purpose of this study was to compare operative strategies for perforated diverticulitis. DATA SOURCES: MEDLINE, Embase, Cochrane Library, and the grey literature were searched from inception to October 2017. STUDY SELECTION: We included randomized clinical trials evaluating operative strategies for perforated diverticulitis. INTERVENTIONS: Hartmann procedure, primary resection and anastomosis, and laparoscopic lavage were included. MAIN OUTCOME MEASURES: Data were independently extracted by 2 investigators. Risk of bias was evaluated using the Cochrane risk-of-bias tool. Pooled risk ratios for major complications, reoperation, and mortality were determined using random-effects models. RESULTS: Six trials including 626 patients with perforated diverticulitis were identified. Laparoscopic lavage and sigmoidectomy had comparable rates of early reoperation and postoperative mortality; major complications (Clavien-Dindo >IIIa) were more frequent after laparoscopic lavage (RR = 1.68 (95% CI, 1.10-2.56); 3 trials, 305 patients). Comparing approaches for sigmoidectomy, primary resection and anastomosis had similar rates of major complications (RR = 0.88 (95% CI, 0.49-1.55); 3 trials, 255 patients) and postoperative mortality (RR = 0.58 (95% CI, 0.20-1.70); 3 trials, 254 patients) compared with the Hartmann procedure. However, patients who underwent primary resection and anastomosis were more likely to be stoma free at 12 months compared with the Hartmann procedure (RR = 1.40 (95% CI, 1.18-1.67); 4 trials, 283 patients) and to experience fewer major complications related to the stoma reversal procedure (RR = 0.26 (95% CI, 0.07-0.89); 4 trials, 186 patients). LIMITATIONS: There were no limitations to this study. CONCLUSIONS: Laparoscopic lavage is associated with increased risk of major complications versus primary resection for Hinchey III diverticulitis. The lower rate of stoma reversal and higher rate of complications after the Hartmann procedure suggest primary resection and anastomosis as the optimal management of perforated diverticulitis.


Assuntos
Colo Sigmoide/cirurgia , Doença Diverticular do Colo/cirurgia , Perfuração Intestinal/cirurgia , Complicações Pós-Operatórias/etiologia , Anastomose Cirúrgica , Procedimentos Cirúrgicos do Sistema Digestório/efeitos adversos , Procedimentos Cirúrgicos do Sistema Digestório/métodos , Doença Diverticular do Colo/complicações , Humanos , Perfuração Intestinal/etiologia , Laparoscopia/efeitos adversos , Irrigação Terapêutica/efeitos adversos
18.
Anesth Analg ; 127(4): 840-849, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29683829

RESUMO

BACKGROUND: Despite its central role in early trauma coagulopathy, abnormal fibrinolysis continues to be poorly understood. Excessive fibrinolysis is a known contributor to mortality. Recent studies with thromboelastography (TEG) suggest decreased fibrinolysis (or shutdown) may be just as harmful. Considering the broad use of 2 different viscoelastic assays, which are not interchangeable, we proposed for the first time to define and characterize fibrinolysis shutdown using rotational thromboelastometry (ROTEM). METHODS: Retrospective cohort study of severely injured patients with admission ROTEM. Shutdown was defined by the best Youden index value of the maximum lysis. Fibrinolysis phenotypes were physiologic, hyperfibrinolysis, and shutdown. Multivariable logistic regression evaluated association between Injury Severity Score and the fibrinolysis phenotypes, and the association among shutdown phenotype with mortality, blood transfusion, and thrombotic events. RESULTS: Five hundred fifty patients were included. Maximum lysis <3.5% was selected to define shutdown. Predominant phenotype was physiologic (70.7%), followed by shutdown (25.6%) and hyperfibrinolysis (3.6%). Shutdown patients had higher Injury Severity Score, lower base excess, and required more transfusions than physiologic group. Shutdown was associated with acidosis (base excess: odds ratio [OR] for a 1 mEq/L increase, 0.93; 95% confidence interval [CI], 0.88-0.98; P = .0094) and the combination of clotting derangements, higher clot firmness (maximum clot formation: OR for a 2 mm increase, 1.8; 95% CI, 1.5-2.27; P < .0001), lower fibrinogen (OR for a 0.5 g/dL decrease, 1.47; 95% CI, 1.18-1.84; P = .0006), and poor clot formation dynamics (clot formation time: OR for a 5 seconds increase, 1.25; 95% CI, 1.15-1.36; P < .0001). Fibrinolysis shutdown was not independently associated with mortality (OR, 0.61; 95% CI, 0.28-1.33; P = .21), massive transfusion (OR, 2.14; 95% CI, 0.79-5.74; P = .1308), or thrombotic events (OR, 1.08; 95% CI, 0.37-3.15; P = .874). Shutdown was associated with increased 24-hour transfusion (OR, 2.24; 95% CI, 1.24-4.04; P = .007). CONCLUSIONS: Despite higher injury burden, evidence of shock, and greater need for blood transfusions, early fibrinolysis shutdown was not associated with mortality, suggesting that it could represent an adaptive physiologic response to life-threatening trauma.


Assuntos
Transtornos da Coagulação Sanguínea/diagnóstico , Fibrinólise , Tromboelastografia , Ferimentos e Lesões/diagnóstico , Adaptação Fisiológica , Adulto , Idoso , Transtornos da Coagulação Sanguínea/sangue , Transtornos da Coagulação Sanguínea/mortalidade , Transtornos da Coagulação Sanguínea/terapia , Transfusão de Sangue , Feminino , Fibrinogênio/metabolismo , Humanos , Escala de Gravidade do Ferimento , Masculino , Pessoa de Meia-Idade , Fenótipo , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Ferimentos e Lesões/sangue , Ferimentos e Lesões/mortalidade , Ferimentos e Lesões/terapia , Adulto Jovem
19.
HPB (Oxford) ; 20(10): 905-915, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29887263

RESUMO

BACKGROUND: A large proportion of patients with colorectal cancer liver metastases (CRCLM) not amenable to curative liver resection will progress on systemic therapy. Intra-arterial therapies (IAT) including conventional transarterial chemoembolization (cTACE), drug eluting beads (DEB-TACE) and yttrium-90 radioembolization (Y-90) are indicated to prolong survival and palliate symptoms. The purpose of this systematic review and meta-analysis is to compare the survival benefit and radiologic response of three intra-arterial therapies in patients with chemorefractory and unresectable CRCLM. METHODS: A systematic search for eligible references in the Cochrane Library and the EMBASE, MEDLINE and TRIP databases from January 2000 to November 2016 was performed in accordance with PRISMA guidelines. Methodological quality of included studies was assessed using the MINORS scale. One-year overall survival rates and RECIST responder rates were pooled using inverse-variance weighted random-effects models. Overall survival outcomes were collected according to transformed pooled median survivals from first IAT with a subgroup analysis of patients with extrahepatic disease. RESULTS: Twenty-three prospective studies were included and analyzed: 5 cTACE (n = 746), 5 DEB-TACE (n = 222) and 13 Y-90 (n = 615). All but five were clinical trials. Eleven of 13 Y-90 studies were industry funded. Pooled RECIST response rates with 95% confidence intervals (CI) were: cTACE 23% (9.7, 36), DEB-TACE 36% (0, 73) and Y-90 23% (11, 34). The pooled 1-year survival rates with CI were: cTACE, 70% (49, 87), DEB-TACE, 80% (74, 86) and Y-90, 41% (28, 54). Transformed pooled median survivals from first IAT and ranges for cTACE, DEB-TACE and Y-90 were 16 months (9.0-23), 16 months (7.3-25) and 12 months (7.0-15), respectively. Significant heterogeneity in inclusion criteria and reporting of confounders, including previous therapy, tumor burden and post-IAT therapy, precluded statistical comparisons between the three therapies. CONCLUSION: Methodological and statistical heterogeneity precluded consensus on the optimal treatment strategy. Given the common use and significant cost of radioembolization in this setting, a more robust prospective comparative trial is warranted.


Assuntos
Braquiterapia , Quimioembolização Terapêutica , Neoplasias Colorretais/patologia , Resistencia a Medicamentos Antineoplásicos , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/terapia , Compostos Radiofarmacêuticos/administração & dosagem , Radioisótopos de Ítrio/administração & dosagem , Idoso , Braquiterapia/efeitos adversos , Braquiterapia/mortalidade , Quimioembolização Terapêutica/efeitos adversos , Quimioembolização Terapêutica/mortalidade , Neoplasias Colorretais/mortalidade , Feminino , Humanos , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Compostos Radiofarmacêuticos/efeitos adversos , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Radioisótopos de Ítrio/efeitos adversos
20.
J Exp Zool B Mol Dev Evol ; 328(1-2): 106-118, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27649924

RESUMO

In early theropod dinosaurs-the ancestors of birds-the hallux (digit 1) had an elevated position within the foot and had lost the proximal portion of its metatarsal. It no longer articulated with the ankle, but was attached at about mid-length of metatarsal 2 (mt2). In adult birds, the hallux is articulated closer to the distal end of mt2 at ground level with the other digits. However, on chick embryonic day 7, its position is as in early theropods at half-length of mt2. The adult distal location is acquired during embryonic days 8-10. To assess how the adult phenotype is acquired, we produced fate maps of the metatarsals of day 6 chicken embryos injecting the lipophilic tracer DiI. The fates of these marks indicate a larger expansion of the metatarsals at their proximal end, which creates the illusory effect that d1 moves distally. This larger proximal expansion occurs concomitantly with growth and early differentiation of cartilage. Histological analysis of metatarsals shows that the domains of flattened and prehypertrophic chondrocytes are larger toward the proximal end. The results suggest that the distal position of the hallux in the avian foot evolved as a consequence of an embryological period of expansion of the metatarsus toward the proximal end. It also brings attention to the developmental mechanisms leading to differential growth between epiphyses and their evolutionary consequences.


Assuntos
Evolução Biológica , Dinossauros/anatomia & histologia , Pé/embriologia , Ossos do Metatarso/embriologia , Adaptação Fisiológica/fisiologia , Animais , Embrião de Galinha , Ossos do Pé/embriologia
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