RESUMO
The organelle paralogy hypothesis is one model for the acquisition of nonendosymbiotic organelles, generated from molecular evolutionary analyses of proteins encoding specificity in the membrane traffic system. GTPase activating proteins (GAPs) for the ADP-ribosylation factor (Arfs) GTPases are additional regulators of the kinetics and fidelity of membrane traffic. Here we describe molecular evolutionary analyses of the Arf GAP protein family. Of the 10 subfamilies previously defined in humans, we find that 5 were likely present in the last eukaryotic common ancestor. Of the 3 most recently derived subfamilies, 1 was likely present in the ancestor of opisthokonts (animals and fungi) and apusomonads (flagellates classified as the sister lineage to opisthokonts), while 2 arose in the holozoan lineage. We also propose to have identified a novel ancient subfamily (ArfGAPC2), present in diverse eukaryotes but which is lost frequently, including in the opisthokonts. Surprisingly few ancient domains accompanying the ArfGAP domain were identified, in marked contrast to the extensively decorated human Arf GAPs. Phylogenetic analyses of the subfamilies reveal patterns of single and multiple gene duplications specific to the Holozoa, to some degree mirroring evolution of Arf GAP targets, the Arfs. Conservation, and lack thereof, of various residues in the ArfGAP structure provide contextualization of previously identified functional amino acids and their application to Arf GAP biology in general. Overall, our results yield insights into current Arf GAP biology, reveal complexity in the ancient eukaryotic ancestor and integrate the Arf GAP family into a proposed mechanism for the evolution of nonendosymbiotic organelles.
Assuntos
Fatores de Ribosilação do ADP/genética , Fatores de Ribosilação do ADP/química , Fatores de Ribosilação do ADP/classificação , Sequência de Aminoácidos , Animais , Coanoflagelados/química , Coanoflagelados/genética , Sequência Conservada , Evolução Molecular , Proteínas Fúngicas/química , Proteínas Fúngicas/classificação , Proteínas Fúngicas/genética , Fungos/química , Fungos/genética , Duplicação Gênica , Dados de Sequência Molecular , Família Multigênica , Filogenia , Estrutura Terciária de Proteína , Proteínas de Protozoários/química , Proteínas de Protozoários/classificação , Proteínas de Protozoários/genética , Homologia de SequênciaRESUMO
Objective: Patients presenting with total body surface area (TBSA) >40% burns require significant surgical treatment. Two substantial challenges during these surgeries are limiting blood loss and maintaining core temperatures. To overcome these challenges, several techniques have been developed, ranging from the Pitkin syringe method to the pneumatic tourniquet strategy for large-volume hyperthermic insufflation. Here, we compare the pneumatic tourniquet method to a roller pump method for maintenance of intraoperative normothermia and control of bleeding. Methods: We conducted a retrospective chart review of 20 patients presenting with TBSA >40% burns, 10 of whom were treated with the rapid infusion roller pump and 10 of whom were treated with the pneumatic tourniquet technique. Patients from each group were controlled for % TBSA, presence of inhalation injury, age, and date of admission. We reviewed transfusion requirement and the intraoperative temperatures, as well as the average intraoperative drop in temperature. Results: We observed improvement in the infusion volume, operative time, intraoperative temperature drop, minimum intraoperative temperature, estimated blood loss, and amount of required transfusion. Conclusions: Our study suggests that the rapid infusion roller pump technique is capable of achieving superior intraoperative bleeding control and temperature maintenance compared to the pneumatic tourniquet technique, resulting in decreased transfusion requirement.
Objectif: Les patients ayant des brûlures sur plus de 40% de la surface corporelle totale (SCT) nécessitent un traitement chirurgical significatif. Ces interventions chirurgicales sont confrontées à deux défis majeurs: la limitation des pertes sanguines et le maintien de la température corporelle. Pour vaincre ces défis, plusieurs techniques ont été développées, allant de la méthode de la seringue de Pitkin à la stratégie du garrot pneumatique pour insufflation hyperthermique de grand volume. Nous comparons ici la méthode du garrot pneumatique à la méthode de la pompe à galets pour le maintien de la normothermie peropératoire et le contrôle des saignements. Méthodes: Nous avons mené une étude rétrospective des dossiers de 20 patients présentant des brûlures sur > 40 % de la SCT; 10 d'entre eux ont été traités avec la pompe à galets pour perfusion rapide et 10 ont été traités avec la technique du garrot pneumatique. Les patients de chaque groupe ont été contrôlés pour le pourcentage de SCT, la présence de lésions d'inhalation, l'âge et la date de leur hospitalisation. Nous avons revu les besoins en transfusion ainsi que les températures peropératoires et la chute moyenne peropératoire de la température. Résultats: Nous avons observé une amélioration du volume de perfusion, de la durée d'intervention, de la chute peropératoire de la température, de la température peropératoire minimum, de la perte sanguine estimée et de la quantité requise de transfusion. Conclusions: Notre étude suggère que la technique de perfusion rapide avec une pompe à galets permet d'obtenir un meilleur contrôle peropératoire des saignements que la technique avec garrot pneumatique, aboutissant à une diminution des besoins de transfusions.
RESUMO
The present article chronicles the career of Dr Albert Ross Tilley, one of the most important Canadian plastic surgeons of the 20th century. Tilley is most well known for his innovations of burn management during World War II and his treatment of a group of burn patients known affectionately as the 'Guinea Pig Club'. In addition to the superb surgical skills he applied to the physical wounds of his patients, Tilley was also a pioneer of caring for the emotional and psychological afflictions suffered by many airmen of World War II. As one of the founding fathers of the Canadian Society of Plastic Surgeons, Tilley's work was instrumental in establishing the specialty and ensured its prosperity for years to come. Serving in the capacity of leader, educator and innovator, Tilley remains one of Canada's most decorated physicians, and his body of work encompasses contributions to the medical field that remain significant and beneficial to patient care to this day.
Le présent article relate la carrière d'Albert Ross Tilley, l'un des plasticiens canadiens les plus importants du XXe siècle. Il est réputé pour ses innovations dans la prise en charge des brûlures pendant la Deuxième Guerre mondiale et pour le traitement d'un groupe de patients brûlés connu affectueusement sous le nom de « club des cobayes ¼. Outre les remarquables compétences chirurgicales qu'il utilisait pour soigner les plaies de ses patients, le docteur Tilley était également un pionnier des soins des problèmes affectifs et psychologiques dont ont souffert de nombreux pilotes de la Deuxième Guerre mondiale. Le docteur Tilley est l'un des fondateurs de la Société canadienne des chirurgiens plasticiens, et par ses travaux, il a contribué à établir la spécialité et à en garantir la prospérité pendant des années. Leader, formateur et innovateur, le docteur Tilley demeure l'un des médecins canadiens les plus décorés, et encore aujourd'hui, son apport à la médecine demeure important et bénéfique pour les soins aux patients.
RESUMO
Thermal injury can result in substantial auricular deformity and subsequent psychosocial morbidity. Helical rim repair, in particular, poses formidable challenges to the reconstructive surgeon. Bi-pedicled tube flaps are one option that have the potential to restore much of the helix's natural contours. This case report discusses the unique strengths and weaknesses of the flap, as well as the reasoning that must be implemented when deciding which situations are appropriate for its utilization. Superior outcomes resulting in a high degree of patient and surgeon satisfaction are possible when the techniques of this report are employed appropriately.
Assuntos
Queimaduras/cirurgia , Pavilhão Auricular/lesões , Pavilhão Auricular/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Retalhos Cirúrgicos , Adulto , HumanosRESUMO
Often considered a defining eukaryotic feature, the Golgi body is one of the most recognizable and functionally integrated cellular organelles. It is therefore surprising that some unicellular eukaryotes do not, at first glance, appear to possess Golgi stacks. Here we review the molecular evolutionary, genomic and cell biological evidence for Golgi bodies in these organisms, with the organelle likely present in some form in all cases. This, along with the overwhelming prevalence of stacked cisternae in most eukaryotes, implies that the ancestral eukaryote possessed a stacked Golgi body, with at least eight independent instances of Golgi unstacking in our cellular history.