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1.
J Thromb Haemost ; 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38705387

RESUMO

Antiphospholipid syndrome (APS) is characterized by thrombosis (which may be venous, arterial, or microvascular) and/or pregnancy morbidity in association with persistently positive antiphospholipid antibodies. Although thrombosis and pregnancy morbidity are the main clinical criteria for a diagnosis of APS in the revised Sapporo (Sydney) criteria, recently published American College of Rheumatology/European Alliance of Associations for Rheumatology classification criteria for APS have significantly refined the diagnostic algorithm to include a scoring system clustered into 6 clinical domains (macrovascular venous thromboembolism, macrovascular arterial thrombosis, microvascular thrombosis, obstetric, cardiac valve, and hematologic). Diagnosis of APS is complicated by the fact that significant heterogeneity exists in patients' clinical presentation, underlying vascular risk factors, and methods of detecting antiphospholipid antibodies. Despite the autoimmune nature of APS, anticoagulation remains the main strategy for secondary prevention of thrombosis. Furthermore, optimal antithrombotic treatment in APS patients with arterial thrombosis remains controversial due to a paucity of data from randomized controlled studies. In this paper, we present 2 cases and highlight the diagnostic and therapeutic challenges they pose and how we approach them in the light of current evidence.

2.
Laryngoscope ; 134(4): 1961-1966, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37776254

RESUMO

OBJECTIVE: To review cases of congenital frontonasal dermoids to gain insight into the accuracy of preoperative computed tomography (CT) and magnetic resonance imaging (MRI) in predicting intracranial extension. METHODS: This retrospective study included all patients who underwent primary excision of frontonasal dermoids at an academic children's hospital over a 23-year period. Preoperative presentation, imaging, and operative findings were reviewed. Receiver operating characteristic (ROC) statistics were generated to determine CT and MRI accuracy in detecting intracranial extension. RESULTS: Search queries yielded 129 patients who underwent surgical removal of frontonasal dermoids over the study period with an average age of presentation of 12 months. Preoperative imaging was performed on 122 patients, with 19 patients receiving both CT and MRI. CT and MRI were concordant in the prediction of intracranial extension in 18 out of 19 patients. Intraoperatively, intracranial extension requiring craniotomy was seen in 11 patients (8.5%). CT was 87.5% sensitive and 97.4% specific for predicting intracranial extension with an ROC of 0.925 (95% CI [0.801, 1]), whereas MRI was 60.0% sensitive and 97.8% specific with an ROC of 0.789 (95% CI [0.627, 0.950]). CONCLUSION: This is the largest case series in the literature describing a single institution's experience with frontonasal dermoids. Intracranial extension is rare and few patients required craniotomy in our series. CT and MRI have comparable accuracy at detecting intracranial extension. Single-modality imaging is recommended preoperatively in the absence of other clinical indications. LEVEL OF EVIDENCE: 4 Laryngoscope, 134:1961-1966, 2024.


Assuntos
Cisto Dermoide , Neoplasias Nasais , Criança , Humanos , Lactente , Cisto Dermoide/diagnóstico por imagem , Cisto Dermoide/cirurgia , Imageamento por Ressonância Magnética , Neoplasias Nasais/cirurgia , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
3.
PeerJ ; 11: e15866, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37663288

RESUMO

Every fall, juvenile sea turtles in the Northwest Atlantic Ocean are threatened by rapidly declining water temperatures. When sea turtles become hypothermic, or cold-stunned, they lose mobility-either at the surface, subsurface, or the bottom of the water column-and eventually strand at the shoreline where rescue teams associated with the Sea Turtle Stranding and Salvage Network may search for them. Understanding the effects of ocean currents on the potential stranding locations of cold-stunned sea turtles is essential to better understand stranding hotspots and increase the probability of successful discovery and recovery of turtles before they die in the cold temperatures. Traditional oceanographic drifters-instruments used to track currents-have been used to examine relationships between current and stranding locations in Cape Cod Bay, but these drifters are not representative of sea turtle morphology and do not assess how bottom currents affect stranding locations. To address these knowledge gaps, we designed new drifters that represent the shape and dimensions of sea turtles-one that can float at the surface and one that sinks to the bottom-to track both surface and bottom currents in Cape Cod Bay. We found a marked difference between the trajectories of our new drifter models and those that were previously used for similar research. These findings bring us one step closer to identifying the transport pathways for cold-stunned sea turtles and optimizing cold-stunned sea turtle search and rescue efforts in Cape Cod.


Assuntos
Temperatura Baixa , Tartarugas , Animais , Baías , Confusão , Massachusetts , Água
4.
Adv Surg ; 57(1): 233-256, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37536856

RESUMO

Prehospital resuscitation is a dynamic field now being energized by new technologies and a shift in thinking regarding intravascular resuscitation. Growing evidence discourages use of intravenous (IV) crystalloid and colloid solutions in trauma, whereas blood products, particularly whole blood, are becoming preferred. Although randomized clinical trials validating definitive resuscitative protocols are still lacking, most preclinical and clinical indicators support this approach. In addition, emerging technologies such as external and endovascular hemorrhage control devices and extracorporeal perfusion are now being used routinely, even in the prehospital setting in many countries, generating new lines of emerging investigations for trauma specialists.


Assuntos
Serviços Médicos de Emergência , Ferimentos e Lesões , Humanos , Hemorragia/terapia , Ressuscitação/métodos , Perfusão , Soluções Cristaloides
5.
Facial Plast Surg ; 38(6): 613-622, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36563672

RESUMO

The subperiosteal midface lift is a powerful tool that allows the surgeon to reposition the SOOF and malar fat pad in a vertical direction. Additionally, it significantly softens deep nasolabial folds. Its effect, however, is minimal with regards to addressing the jowl, jawline, gonial angle and cervicomental angle. Combining the subperiosteal midface lift with an extended sub-SMAS rhytidectomy addresses the pre-jowl sulcus by releasing the mandibular ligament. The jawline and gonial angle become more defined with the transposition and suspension of the SMAS flap. The SMAS transposition flap along with the suspension of the platysma flap to the mastoid fascia support the submandibular glands and deepen the cervicomental angle. These two approaches are valuable additions to the surgeons armamentarium and can yield excellent results in carefully selected patients.


Assuntos
Ritidoplastia , Humanos , Ritidoplastia/métodos , Face , Bochecha , Mandíbula , Fáscia
6.
J Environ Radioact ; 255: 107039, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36272273

RESUMO

Near-surface drifter observations were used to study the spreading pathways in and around the Cape Cod Bay from a source region located just offshore of the Pilgrim Nuclear Power Station. The study was motivated by the recent closing of the power plant and a possible release of accumulated wastewater. The investigation applies several different techniques to the drifter data set to estimate and quantify various aspects of the circulation and spreading. Our goal was two-fold: first, to better understand and predict the fate of the Pilgrim wastewater should it be released; and second, to review, compare, and contrast several useful techniques that can be applied to drifter datasets in other parts of the global ocean. Our analysis suggests weaker spreading of the wastewater plume inside the Bay than outside, and sensitivity of the advection pathways to the location of the release. Statistical techniques predicted that part of the plume would likely be advected cyclonically around the inner coastline of the Bay towards the more quiescent eastern regions, while another part of the plume would likely pass close to the tip of Cape Cod and the beaches of the Outer Cape. For the soluble radionuclides, the levels observed in our statistical model offshore of Provincetown and Dennis/Brewster will be at least 100 times smaller than the initial concentrations.


Assuntos
Monitoramento de Radiação , Águas Residuárias , Baías
7.
Obstet Med ; 15(1): 45-49, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35444730

RESUMO

Aims: To report pregnancy outcomes and complications in women receiving eculizumab for the management of paroxysmal nocturnal haemoglobinuria. Methods: A service evaluation of routinely collected medical records across 49 pregnancies in 21 women. Results: Eculizumab was used in 37 pregnancies, 31 of which (83.8%) ended in live birth. Eight infants (25.8%) were born prematurely. Over half (54%) of women required increases in their dose of eculizumab to control their haemolysis. There were no reported cases of maternal thrombosis. Major ante/postpartum bleeding necessitating urgent intervention was reported in 10.8% of pregnancies. There were two cases of intrauterine death and three miscarriages. There were no maternal or neonatal deaths. Three newborns required prolonged hospital stays. Conclusions: Eculizumab appears to benefit pregnant women with paroxysmal nocturnal haemoglobinuria and pregnancy outcomes following its use are largely good.

8.
Facial Plast Surg ; 37(6): 698-702, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34521150

RESUMO

Calvarial defects are commonly encountered after neurosurgical procedures, trauma, and ablative procedures of advanced head neck cancers. The goals of cranioplasty are to provide a protective barrier for the intracranial contents, to restore form, and prevent syndrome of the trephined. Autologous and alloplastic techniques are available, each with their advantages and drawbacks. A multitude of materials are available for cranioplasty, and proper timing of reconstruction with attention to the overlying skin envelope is important in minimizing complications.


Assuntos
Procedimentos de Cirurgia Plástica , Humanos , Crânio/cirurgia , Transplante Autólogo
9.
J Trauma Acute Care Surg ; 91(4): e104-e113, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34238862

RESUMO

ABSTRACT: Endovascular resuscitation is an emerging area in the resuscitation of both severe traumatic hemorrhage and nontraumatic cardiac arrest. Vascular access is the critical first procedural step that must be accomplished to initiate endovascular resuscitation. The endovascular interventions presently available and emerging are routinely or potentially performed via the femoral vessels. This may require either femoral arterial access alone or access to both the femoral artery and vein. The time-critical nature of resuscitation necessitates that medical specialists performing endovascular resuscitation be well-trained in vascular access techniques. Keen knowledge of femoral vascular anatomy and skill with vascular access techniques are required to meet the needs of critically ill patients for whom endovascular resuscitation can prove lifesaving. This review article addresses the critical importance of femoral vascular access in endovascular resuscitation, focusing on the pertinent femoral vascular anatomy and technical aspects of ultrasound-guided percutaneous vascular access and femoral vessel cutdown that may prove helpful for successful endovascular resuscitation.


Assuntos
Procedimentos Endovasculares/métodos , Parada Cardíaca/terapia , Hemorragia/terapia , Ressuscitação/métodos , Ferimentos e Lesões/complicações , Artéria Femoral/cirurgia , Hemorragia/diagnóstico , Hemorragia/etiologia , Humanos , Índice de Gravidade de Doença , Ferimentos e Lesões/terapia
10.
J Am Coll Emerg Physicians Open ; 1(5): 737-743, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33145513

RESUMO

Resuscitative endovascular balloon occlusion of the aorta (REBOA) has been proposed as a novel approach to managing non-traumatic cardiac arrest (NTCA). During cardiac arrest, cardiac output ceases and perfusion of vital organs is compromised. Traditional advanced cardiac life support (ACLS) measures and cardiopulmonary resuscitation are often unable to achieve return of spontaneous circulation (ROSC). During insertion of REBOA a balloon-tipped catheter is placed into the femoral artery and advanced in a retrograde manner into the aorta while the patient is undergoing cardiopulmonary resuscitation (CPR). The balloon is then inflated to fully occlude the aorta. The literature surrounding the use of aortic occlusion in non-traumatic cardiac arrest is limited to animal studies, case reports and one recent non-controlled feasibility trial. In both human and animal studies, preliminary data show that REBOA may improve coronary and cerebral perfusion pressures and key physiologic parameters during cardiac arrest resuscitation, and animal data have demonstrated improved rates of ROSC. Multiple questions remain before REBOA can be considered as an adjunct to ACLS. If demonstrated to be effective clinically, REBOA represents a potentially cost-effective and generalizable intervention that may improve quality of life for patients with non-traumatic cardiac arrest.

11.
Crit Care Explor ; 2(10): e0214, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33134932

RESUMO

OBJECTIVES: To construct a highly detailed yet practical, attainable roadmap for enhancing the likelihood of neurologically intact survival following sudden cardiac arrest. DESIGN SETTING AND PATIENTS: Population-based outcomes following out-of-hospital cardiac arrest were collated for 10 U.S. counties in Alaska, California, Florida, Ohio, Minnesota, Utah, and Washington. The 10 identified emergency medical services systems were those that had recently reported significant improvements in neurologically intact survival after introducing a more comprehensive approach involving citizens, hospitals, and evolving strategies for incorporating technology-based, highly choreographed care and training. Detailed inventories of in-common elements were collated from the ten 9-1-1 agencies and assimilated. For reference, combined averaged outcomes for out-of-hospital cardiac arrest occurring January 1, 2017, to February 28, 2018, were compared with concurrent U.S. outcomes reported by the well-established Cardiac Arrest Registry to Enhance Survival. INTERVENTIONS: Most commonly, interventions and components from the ten 9-1-1 systems consistently included extensive public cardiopulmonary resuscitation training, 9-1-1 system-connected smart phone applications, expedited dispatcher procedures, cardiopulmonary resuscitation quality monitoring, mechanical cardiopulmonary resuscitation, devices for enhancing negative intrathoracic pressure regulation, extracorporeal membrane oxygenation protocols, body temperature management procedures, rapid cardiac angiography, and intensive involvement of medical directors, operational and quality assurance officers, and training staff. MEASUREMENTS AND MAIN RESULTS: Compared with Cardiac Arrest Registry to Enhance Survival (n = 78,704), the cohorts from the 10 emergency medical services agencies examined (n = 2,911) demonstrated significantly increased likelihoods of return of spontaneous circulation (mean 37.4% vs 31.5%; p < 0.001) and neurologically favorable hospital discharge, particularly after witnessed collapses involving bystander cardiopulmonary resuscitation and shockable cardiac rhythms (mean 10.7% vs 8.4%; p < 0.001; and 41.6% vs 29.2%; p < 0.001, respectively). CONCLUSIONS: The likelihood of neurologically favorable survival following out-of-hospital cardiac arrest can improve substantially in communities that conscientiously and meticulously introduce a well-sequenced, highly choreographed, system-wide portfolio of both traditional and nonconventional approaches to training, technologies, and physiologic management. The commonalities found in the analyzed systems create a compelling case that other communities can also improve out-of-hospital cardiac arrest outcomes significantly by conscientiously exploring and adopting similar bundles of system organization and care.

12.
Anal Biochem ; 599: 113730, 2020 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-32289258

RESUMO

The Root Effect is to many species of fish what the Bohr Effect is to humans regarding the release of O2 from their hemoglobins at low pH. However, Root Effect hemoglobins accomplish this more extensively than human adult hemoglobin in order to satisfy the diverse oxygen requirements in fish. To understand this difference between fish and human hemoglobins, we studied their subunit interface strengths using very low (nanomolar) concentrations, referred to as nano gel filtration. Root Effect hemoglobins in their CO form dissociate in a tetramer-monomer equilibrium. In contrast, tetramers and dimers but no monomers are found for adult human hemoglobin consistent with its well known tetramer-dimer equilibrium. By analogy to the human variant Hb Kansas and a similar recombinant Hb, both of which readily release oxygen due to an unstable oxygenated structure, the mechanism proposed is that oxygenated Root Effect tetramers release their oxygen to form energetically stable deoxygenated tetramers rather than dissociate to energetically unfavorable oxygenated dimers with labile interfaces. In contrast, the strong binding of CO permits observation of dissociation to monomers, thus revealing an intrinsic property of Root Effect fish hemoglobins enabling it to function as an oxygen pump.


Assuntos
Peixes/metabolismo , Hemoglobinas/metabolismo , Oxigênio/metabolismo , Animais , Filtração , Humanos , Cinética , Nanotecnologia
13.
J Trauma Acute Care Surg ; 89(2S Suppl 2): S50-S58, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32345902

RESUMO

This article reviews four emerging endovascular hemorrhage control and extracorporeal perfusion techniques for management of trauma patients with profound hemorrhagic shock including hemorrhage-induced traumatic cardiac arrest: resuscitative endovascular balloon occlusion of the aorta, selective aortic arch perfusion, extracorporeal life support, and emergency preservation and resuscitation. The preclinical and clinical studies underpinning each of these techniques are summarized. We also present an integrated conceptual framework for how these emerging technologies may be used in the future care of trauma patients in both resource-rich and austere environments.


Assuntos
Oclusão com Balão/métodos , Procedimentos Endovasculares/métodos , Oxigenação por Membrana Extracorpórea , Hemorragia/terapia , Ressuscitação/métodos , Choque Hemorrágico/terapia , Aorta , Parada Cardíaca/terapia , Humanos , Hipotermia Induzida , Choque Hemorrágico/prevenção & controle , Ferimentos e Lesões/terapia
14.
Subcell Biochem ; 94: 275-296, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32189304

RESUMO

During the past two decades, significant advances have been made in our understanding of the human fetal and embryonic hemoglobins made possible by the availability of pure, highly characterized materials and novel methods, e.g., nano gel filtration, to study their properties and to correct some misconceptions. For example, whereas the structures of the human adult, fetal, and embryonic hemoglobins are very similar, it has generally been assumed that functional differences between them are due to primary sequence effects. However, more recent studies indicate that the strengths of the interactions between their subunits are very different leading to changes in their oxygen binding properties compared to adult hemoglobin. Fetal hemoglobin in the oxy conformation is a much stronger tetramer than adult hemoglobin and dissociates to dimers 70-times less than adult hemoglobin. This property may form the basis for its protective effect against malaria. A major source of the increased strength of fetal hemoglobin resides within the A-helix of its gamma subunit as demonstrated in studies with the hybrid hemoglobin Felix and related hybrids. Re-activating fetal hemoglobin synthesis in vivo is currently a major focus of clinical efforts designed to treat sickle cell anemia since it inhibits the aggregation of sickle hemoglobin. The mechanisms for both the increased oxygen affinity of fetal hemoglobin and its decreased response to DPG have been clarified. Acetylated fetal hemoglobin, which makes up 10-20% of total fetal hemoglobin, has a significantly weakened tetramer structure suggesting a similar role for other kinds of protein acetylation. Embryonic hemoglobins have the weakest tetramer and dimer structures. In general, the progressively increasing strength of the subunit interfaces of the hemoglobin family during development from the embryonic to the fetal and ultimately to the adult types correlates with their temporal appearance and disappearance in vivo, i.e., ontogeny.


Assuntos
Embrião de Mamíferos/irrigação sanguínea , Hemoglobina Fetal/química , Hemoglobina Fetal/metabolismo , Oxigênio/metabolismo , Feto/irrigação sanguínea , Humanos
15.
J Med Chem ; 63(5): 2263-2281, 2020 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-31589043

RESUMO

ß-Site amyloid precursor protein cleaving enzyme 1 (BACE1) is an aspartyl protease that plays a key role in the production of amyloid ß (Aß) in the brain and has been extensively pursued as a target for the treatment of Alzheimer's disease (AD). BACE2, an aspartyl protease that is structurally related to BACE1, has been recently reported to be involved in melanosome maturation and pigmentation. Herein, we describe the development of a series of cyclopropylthiazines as potent and orally efficacious BACE1 inhibitors. Lead optimization led to the identification of 20, a molecule with biochemical IC50 BACE2/BACE1 ratio of 47. Administration of 20 resulted in no skin/fur color change in a 13-day mouse hypopigmentation study and demonstrated robust and sustained reduction of CSF and brain Aß40 levels in rat and monkey pharmacodynamic models. On the basis of a compelling data package, 20 (AM-6494) was advanced to preclinical development.


Assuntos
Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Ácido Aspártico Endopeptidases/antagonistas & inibidores , Ciclopropanos/farmacologia , Inibidores Enzimáticos/farmacologia , Tiazinas/farmacologia , Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Secretases da Proteína Precursora do Amiloide/metabolismo , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Peptídeos beta-Amiloides/metabolismo , Animais , Ácido Aspártico Endopeptidases/metabolismo , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Ciclopropanos/química , Ciclopropanos/farmacocinética , Ciclopropanos/uso terapêutico , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacocinética , Inibidores Enzimáticos/uso terapêutico , Humanos , Masculino , Camundongos , Modelos Moleculares , Fragmentos de Peptídeos/líquido cefalorraquidiano , Fragmentos de Peptídeos/metabolismo , Ratos Sprague-Dawley , Tiazinas/química , Tiazinas/farmacocinética , Tiazinas/uso terapêutico
16.
Shock ; 54(2): 218-223, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-31851119

RESUMO

BACKGROUND: Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) may improve Systolic Blood Pressure (SBP) in hypovolemic shock. It has, however, not been studied in patients with impending traumatic cardiac arrest (ITCA). We aimed to study the feasibility and clinical outcome of REBOA in patients with ITCA using data from the ABOTrauma Registry. METHODS: Retrospective and prospective data on the use of REBOA from 16 centers globally were collected. SBP was measured both at pre- and post-REBOA inflation. Data collected included patients' demography, vascular access technique, number of attempts, catheter size, operator, zone and duration of occlusion, and clinical outcome. RESULTS: There were 74 patients in this high-risk patient group. REBOA was performed on all patients. A 7-10Fr catheter was used in 66.7% and 58.5% were placed on the first attempt, 52.1% through blind insertion and 93.2% inflated in Zone I, 64.8% for a period of 30 to 60 min, 82.1% by ER doctors, trauma surgeons, or vascular surgeons. SBP significantly improved to 90 mm Hg following the inflation of REBOA. 36.6% of the patients survived. CONCLUSIONS: Our study has shown that REBOA may be performed in patients with ITCA, SBP can be elevated, and 36.6% of the patients survived if REBOA placement is successful.


Assuntos
Oclusão com Balão , Choque Hemorrágico/terapia , Ferimentos e Lesões/terapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Estudos de Viabilidade , Feminino , Parada Cardíaca , Humanos , Escala de Gravidade do Ferimento , Masculino , Pessoa de Meia-Idade , Ressuscitação/métodos , Estudos Retrospectivos , Adulto Jovem
17.
PLoS One ; 14(12): e0204717, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31800593

RESUMO

Kemp's ridley sea turtles were on the verge of extinction in the 1960s. While these sea turtles have slowly recovered, they are still critically endangered. In the last few years, the number of strandings on the beaches of Cape Cod, Massachusetts has increased by nearly an order of magnitude relative to preceding decades. This study uses a combination of ocean observations and a well-respected ocean model to investigate the causes and transport of cold-stunned sea turtles in Cape Cod Bay. After validating the model using satellite-tracked drifters and local temperature moorings, ocean currents were examined in Cape Cod Bay in an attempt to explain stranding locations as observed by volunteers and, for some years, backtracking was conducted to examine the potential source regions. The general finding of this study is that sub 10.5°C water temperatures in combination with persistently strong wind stress (>0.4 Pa), results in increased strandings along particular sections of the coast and are dependent on the wind direction. However, it is still uncertain where in the water column the majority of cold-stunned turtles reside and, if many of them are on the surface, considerable work will need to be done to incorporate the direct effects of wind and waves on the advective processes.


Assuntos
Simulação por Computador , Tartarugas/fisiologia , Animais , Temperatura Baixa , Massachusetts , Vento
18.
J Trauma Acute Care Surg ; 87(2): 263-273, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31348400

RESUMO

BACKGROUND: Hemorrhage-induced traumatic cardiac arrest (HiTCA) has a dismal survival rate. Previous studies demonstrated selective aortic arch perfusion (SAAP) with fresh whole blood (FWB) improved the rate of return of spontaneous circulation (ROSC) after HiTCA, compared with resuscitative endovascular balloon occlusion of the aorta and cardiopulmonary resuscitation (CPR). Hemoglobin-based oxygen carriers, such as hemoglobin-based oxygen carrier (HBOC)-201, may alleviate the logistical constraints of using FWB in a prehospital setting. It is unknown whether SAAP with HBOC-201 is equivalent in efficacy to FWB, whether conversion from SAAP to extracorporeal life support (ECLS) is feasible, and whether physiologic derangement post-SAAP therapy is reversible. METHODS: Twenty-six swine (79 ± 4 kg) were anesthetized and underwent HiTCA which was induced via liver injury and controlled hemorrhage. Following arrest, swine were randomly allocated to resuscitation using SAAP with FWB (n = 12) or HBOC-201 (n = 14). After SAAP was initiated, animals were monitored for a 20-minute prehospital period prior to a 40-minute damage control surgery and resuscitation phase, followed by 260 minutes of critical care. Primary outcomes included rate of ROSC, survival, conversion to ECLS, and correction of physiology. RESULTS: Baseline physiologic measurements were similar between groups. ROSC was achieved in 100% of the FWB animals and 86% of the HBOC-201 animals (p = 0.483). Survival (t = 320 minutes) was 92% (11/12) in the FWB group and 67% (8/12) in the HBOC-201 group (p = 0.120). Conversion to ECLS was successful in 100% of both groups. Lactate peaked at 80 minutes in both groups, and significantly improved by the end of the experiment in the HBOC-201 group (p = 0.001) but not in the FWB group (p = 0.104). There was no significant difference in peak or end lactate between groups. CONCLUSION: Selective aortic arch perfusion is effective in eliciting ROSC after HiTCA in a swine model, using either FWB or HBOC-201. Transition from SAAP to ECLS after definitive hemorrhage control is feasible, resulting in high overall survival and improvement in lactic acidosis over the study period.


Assuntos
Aorta Torácica , Substitutos Sanguíneos/uso terapêutico , Transfusão de Sangue/métodos , Reanimação Cardiopulmonar/métodos , Exsanguinação/complicações , Parada Cardíaca/prevenção & controle , Hemoglobinas/uso terapêutico , Perfusão/métodos , Animais , Substitutos Sanguíneos/administração & dosagem , Modelos Animais de Doenças , Exsanguinação/terapia , Parada Cardíaca/etiologia , Hemoglobinas/administração & dosagem , Masculino , Suínos
19.
Biochemistry ; 57(50): 6816-6821, 2018 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-30431267

RESUMO

The mild acetylating agent, methyl acetyl phosphate, is used to estimate the p Ka values of some of the amine groups in peptides with sequences corresponding to a segment of the N-terminal tail of histone H4. When Ser-1 is not phosphorylated, the Lys ε amines have p Ka values in the range of 7.8-8.3, which are much lower than the currently assumed values. When Ser-1 is phosphorylated, the p Ka values of these Lys amines are elevated to the range of 8.8-10.3, thus providing the rationale for reports that they are then better substrates for acetyltransferases. Thus, reversal of suppressed p Ka values of Lys ε amines by Ser phosphorylation represents the basis for signaling in histone N-terminal tails to promote hyperacetylation, which is a hallmark of transcriptionally active euchromatin. In contrast, a state of hypoacetylation is present in the absence of phosphorylation as in transcriptionally inactive heterochromatin. A novel approach for estimating p Ka values based on a linkage between the Henderson-Hasselbalch and Michaelis-Menten equations indicates that the p Ka values of the Lys ε amines in H3 and H4 N-terminal tails have a highly variable charge gradient dependent on the location and proximity to the phosphorylation site.


Assuntos
Histonas/química , Histonas/metabolismo , Acetilação , Sequência de Aminoácidos , Animais , Sítios de Ligação , Código das Histonas , Histonas/genética , Humanos , Cinética , Lisina/química , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/metabolismo , Ácido Fosfonoacéticos/análogos & derivados , Ácido Fosfonoacéticos/química , Ácido Fosfonoacéticos/metabolismo , Serina/química , Transdução de Sinais , Transcrição Gênica
20.
Int J Food Microbiol ; 283: 45-51, 2018 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-30099994

RESUMO

Filamentous fungi are an invaluable source for biocontrol strategies and for production and development of different antifungal polypeptides. Within this context, cysteine-rich antifungal AFP-like peptides stand out among many different antimicrobial compounds given their production easiness, stability, versatility, and efficacy. AFP from Aspergillus giganteus represents the hallmark of this still increasing family of antifungal polypeptides. Close in silico analyses of the Fusarium graminearum genome revealed the presence of an AFP-like peptide, here designated as FgAFP. This new peptide was cloned, produced in the yeast Pichia pastoris, and characterized. The results obtained showed its strong and specific antifungal activity against several well-recognized maize pathogens, but inefficacy against F. oxysporum, which has not been described as a natural biological competitor of other fungal pathogens assayed. All results together suggest that this small peptide is an important factor for the fungal interplays involved in maize infection and reveals unforeseen potential biotechnological applications for FgAFP in maize production and storage.


Assuntos
Antifúngicos/farmacologia , Fusarium/química , Doenças das Plantas/microbiologia , Zea mays/microbiologia , Antifúngicos/química , Antifúngicos/metabolismo , Cisteína/química , Fusarium/genética , Fusarium/metabolismo , Peptídeos/análise , Peptídeos/metabolismo , Peptídeos/farmacologia
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