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1.
Cell ; 156(3): 394-5, 2014 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-24485447

RESUMO

Cell division entails dramatic membrane rearrangements, but what is the role of lipids in the process? Eggert et al. explore the dynamics of the lipidome during cell division and provide new insights on the functions of specific lipids in cytokinesis.


Assuntos
Divisão Celular , Membrana Celular/química , Lipídeos de Membrana/análise , Humanos
2.
J Cell Sci ; 137(7)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38469748

RESUMO

Equal cell division relies upon astral microtubule-based centering mechanisms, yet how the interplay between mitotic entry, cortical force generation and long astral microtubules leads to symmetric cell division is not resolved. We report that a cortically located sperm aster displaying long astral microtubules that penetrate the whole zygote does not undergo centration until mitotic entry. At mitotic entry, we find that microtubule-based cortical pulling is lost. Quantitative measurements of cortical pulling and cytoplasmic pulling together with physical simulations suggested that a wavelike loss of cortical pulling at mitotic entry leads to aster centration based on cytoplasmic pulling. Cortical actin is lost from the cortex at mitotic entry coincident with a fall in cortical tension from ∼300pN/µm to ∼100pN/µm. Following the loss of cortical force generators at mitotic entry, long microtubule-based cytoplasmic pulling is sufficient to displace the aster towards the cell center. These data reveal how mitotic aster centration is coordinated with mitotic entry in chordate zygotes.


Assuntos
Sêmen , Fuso Acromático , Masculino , Humanos , Microtúbulos , Citoplasma , Divisão Celular
3.
Cell ; 144(3): 414-26, 2011 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-21295701

RESUMO

The spatial organization of cells depends on their ability to sense their own shape and size. Here, we investigate how cell shape affects the positioning of the nucleus, spindle and subsequent cell division plane. To manipulate geometrical parameters in a systematic manner, we place individual sea urchin eggs into microfabricated chambers of defined geometry (e.g., triangles, rectangles, and ellipses). In each shape, the nucleus is positioned at the center of mass and is stretched by microtubules along an axis maintained through mitosis and predictive of the future division plane. We develop a simple computational model that posits that microtubules sense cell geometry by probing cellular space and orient the nucleus by exerting pulling forces that scale to microtubule length. This model quantitatively predicts division-axis orientation probability for a wide variety of cell shapes, even in multicellular contexts, and estimates scaling exponents for length-dependent microtubule forces.


Assuntos
Divisão Celular , Forma Celular , Ouriços-do-Mar/citologia , Animais , Núcleo Celular/metabolismo , Interfase , Microtúbulos/metabolismo , Mitose , Modelos Biológicos , Fuso Acromático/metabolismo
4.
Proc Natl Acad Sci U S A ; 118(21)2021 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-34006642

RESUMO

The interaction of collisionless shocks with fully developed plasma turbulence is numerically investigated. Hybrid kinetic simulations, where a turbulent jet is slammed against an oblique shock, are employed to address the role of upstream turbulence on plasma transport. A technique, using coarse graining of the Vlasov equation, is proposed, showing that the particle transport strongly depends on upstream turbulence properties, such as strength and coherency. These results might be relevant for the understanding of acceleration and heating processes in space plasmas.

5.
Heart Lung Circ ; 32(2): 184-196, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36599791

RESUMO

IMPORTANCE: Randomised trials have shown that catheter ablation (CA) is superior to medical therapy for ventricular tachycardia (VT) largely in patients with ischaemic heart disease. Whether this translates to patients with all forms and stages of structural heart disease (SHD-e.g., non-ischaemic heart disease) is unclear. This trial will help clarify whether catheter ablation offers superior outcomes compared to medical therapy for VT in all patients with SHD. OBJECTIVE: To determine in patients with SHD and spontaneous or inducible VT, if catheter ablation is more efficacious than medical therapy in control of VT during follow-up. DESIGN: Randomised controlled trial including 162 patients, with an allocation ratio of 1:1, stratified by left ventricular ejection fraction (LVEF) and geographical region of site, with a median follow-up of 18-months and a minimum follow-up of 1 year. SETTING: Multicentre study performed in centres across Australia. PARTICIPANTS: Structural heart disease patients with sustained VT or inducible VT (n=162). INTERVENTION: Early treatment, within 30 days of randomisation, with catheter ablation (intervention) or initial treatment with antiarrhythmic drugs only (control). MAIN OUTCOMES, MEASURES, AND RESULTS: Primary endpoint will be a composite of recurrent VT, VT storm (≥3 VT episodes in 24 hrs or incessant VT), or death. Secondary outcomes will include each of the individual primary endpoints, VT burden (number of VT episodes in the 6 months preceding intervention compared to the 6 months after intervention), cardiovascular hospitalisation, mortality (including all-cause mortality, cardiac death, and non-cardiac death) and LVEF (assessed by transthoracic echocardiography from baseline to 6-, 12-, 24- and 36-months post intervention). CONCLUSIONS AND RELEVANCE: The Catheter Ablation versus Anti-arrhythmic Drugs for Ventricular Tachycardia (CAAD-VT) trial will help determine whether catheter ablation is superior to antiarrhythmic drug therapy alone, in patients with SHD-related VT. TRIAL REGISTRY: Australian New Zealand Clinical Trials Registry (ANZCTR) TRIAL REGISTRATION ID: ACTRN12620000045910 TRIAL REGISTRATION URL: https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=377617&isReview=true.


Assuntos
Ablação por Cateter , Isquemia Miocárdica , Taquicardia Ventricular , Humanos , Antiarrítmicos/uso terapêutico , Volume Sistólico , Estudos Prospectivos , Resultado do Tratamento , Função Ventricular Esquerda , Austrália/epidemiologia , Taquicardia Ventricular/cirurgia , Taquicardia Ventricular/etiologia , Isquemia Miocárdica/cirurgia , Ablação por Cateter/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Multicêntricos como Assunto
6.
Antimicrob Agents Chemother ; 66(1): e0088621, 2022 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-34633843

RESUMO

Vancomycin is a first-line agent used in the treatment of methicillin-resistant Staphylococcus aureus; however, vancomycin is associated with acute kidney injury (AKI). Previous literature demonstrates decreased incidence of AKI using 24-h area under the concentration-time curve (AUC24) monitoring, but its safety is unknown in obese populations. Patients ≥18 years, with body mass indices (BMI) ≥30 kg/m2, admitted between August 2015 and July 2017 or October 2017 and September 2019, who received vancomycin for ≥72 h and had level(s) drawn within 96 h of initiation were included. The primary outcome was incidence of AKI. Secondary outcomes included inpatient mortality rate, median inpatient length of stay, median vancomycin trough concentration, and median vancomycin AUC24. AKI was identified using the highest serum creatinine value compared with the value immediately prior to vancomycin initiation based on Kidney Disease Improving Global Outcomes (KDIGO) criteria. Overall, 1,024 patients met inclusion criteria, with 142 out of 626 patients in the trough group and 65 out of 398 patients in the AUC24 group meeting criteria for AKI (22.7% versus 16.3%, P = 0.008). Logistic regression of the data to account for confounding factors maintained significance for the reduction in incidence of AKI with AUC24 monitoring compared to trough monitoring (P = 0.010). Monitoring of vancomycin with AUC24 was associated with a decreased risk of AKI when compared with trough monitoring in obese patients.


Assuntos
Injúria Renal Aguda , Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Injúria Renal Aguda/tratamento farmacológico , Antibacterianos/efeitos adversos , Área Sob a Curva , Humanos , Testes de Sensibilidade Microbiana , Obesidade/tratamento farmacológico , Estudos Retrospectivos , Infecções Estafilocócicas/tratamento farmacológico , Vancomicina/efeitos adversos
7.
Transfusion ; 62(2): 406-417, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34951486

RESUMO

BACKGROUND: Early plasma transfusion is life-saving for bleeding trauma patients. Freeze-dried plasma (FDP) provides unique formulation advantages for infusion in the prehospital setting. We describe characterization and clinical safety data of the first, next-generation FDP stored in plastic bags with rapid reconstitution. STUDY DESIGN AND METHODS: Coagulation and chemistry parameters on 155 pairs of fresh frozen plasma (FFP) and their derivative FDP units were compared. Next, a first-in-human, dose-escalation safety evaluation of FDP, involving 24 healthy volunteers who donated either whole blood or apheresis plasma to create autologous FDP, was performed in three dose cohorts (270, 540, and 810 ml) and adverse events (AEs) were monitored. Cohort 3 was randomized, double-blind with a cross-over arm that compared FDP versus FFP using descriptive analysis for AEs, coagulation, hematology, and chemistry parameters. RESULTS: FDP coagulation factors, clotting times, and product quality (pH, total protein, and osmolality) post-lyophilization were preserved. FDP infusions, of up to 810 ml per subject, were found to be safe and with no serious AEs (SAEs) related to FDP. The average time to reconstitute FDP was 67 s (range: 43-106). No differences in coagulation parameters or thrombin activation were detected in subjects infused with 810 ml of FDP compared with FFP. CONCLUSION: This first next-generation FDP product preserves the potency and safety of FFP in a novel rugged, compressible, plastic container, for rapid transfusion, allowing rapid access to plasma in resuscitation protocols for therapy in acute traumatic hemorrhage.


Assuntos
Transfusão de Componentes Sanguíneos , Plasma , Liofilização/métodos , Hemorragia/terapia , Humanos , Ressuscitação/métodos
8.
Exp Astron (Dordr) ; 54(2-3): 473-519, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36915623

RESUMO

The smallest characteristic scales, at which electron dynamics determines the plasma behaviour, are the next frontier in space and astrophysical plasma research. The analysis of astrophysical processes at these scales lies at the heart of the research theme of electron-astrophysics. Electron scales are the ultimate bottleneck for dissipation of plasma turbulence, which is a fundamental process not understood in the electron-kinetic regime. In addition, plasma electrons often play an important role for the spatial transfer of thermal energy due to the high heat flux associated with their velocity distribution. The regulation of this electron heat flux is likewise not understood. By focussing on these and other fundamental electron processes, the research theme of electron-astrophysics links outstanding science questions of great importance to the fields of space physics, astrophysics, and laboratory plasma physics. In this White Paper, submitted to ESA in response to the Voyage 2050 call, we review a selection of these outstanding questions, discuss their importance, and present a roadmap for answering them through novel space-mission concepts.

9.
Emerg Med J ; 38(1): 33-39, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33172878

RESUMO

BACKGROUND: Mechanical thrombectomy (MT) is a time-sensitive emergency procedure for patients who had ischaemic stroke leading to improved health outcomes. Health systems need to ensure that MT is delivered to as many patients as quickly as possible. Using decision modelling, we aimed to evaluate the cost-effectiveness of secondary transfer by helicopter emergency medical services (HEMS) compared with ground emergency medical services (GEMS) of rural patients eligible for MT in England. METHODS: The model consisted of (1) a short-run decision tree with two branches, representing secondary transfer transportation strategies and (2) a long-run Markov model for a theoretical population of rural patients with a confirmed ischaemic stroke. Strategies were compared by lifetime costs: quality-adjusted life years (QALYs), incremental cost per QALY gained and net monetary benefit. Sensitivity and scenario analyses explored uncertainty around parameter values. RESULTS: We used the base case of early-presenting (<6 hours to arterial puncture) patient aged 75 years who had stroke to compare HEMS and GEMS. This produced an incremental cost-effectiveness ratio (ICER) of £28 027 when a 60 min reduction in travel time was assumed. Scenario analyses showed the importance of the reduction in travel time and futile transfers in lowering ICERs. For late presenting (>6 hours to arterial puncture), ground transportation is the dominant strategy. CONCLUSION: Our model indicates that using HEMS to transfer patients who had stroke eligible for MT from remote hospitals in England may be cost-effective when: travel time is reduced by at least 60 min compared with GEMS, and a £30 000/QALY threshold is used for decision-making. However, several other logistic considerations may impact on the use of air transportation.


Assuntos
Resgate Aéreo/economia , Transferência de Pacientes/economia , Acidente Vascular Cerebral/cirurgia , Trombectomia/economia , Idoso , Aeronaves , Árvores de Decisões , Inglaterra , Feminino , Humanos , Masculino , Cadeias de Markov , Modelos Econômicos , Anos de Vida Ajustados por Qualidade de Vida
10.
Artigo em Inglês | MEDLINE | ID: mdl-32366709

RESUMO

Methicillin-resistant Staphylococcus aureus (MRSA) has grown to become a major burden on health care systems. The cumulation of limited therapeutic options and worsened patient outcomes with persistent MRSA bacteremia has driven research in optimizing its initial management. The guidelines published by the Infectious Diseases Society of America currently recommend combination therapy for refractory MRSA bacteremia, but the utility of combining antibiotics from the start of therapy is under investigation. The alternative strategy of early use of ß-lactam antibiotics in combination with vancomycin upon initial MRSA bacteremia detection has shown promise. While this concept has gained international attention, providers should give this strategy serious consideration prior to implementation. The objective of this review is to examine retrospective and prospective evidence for early combination with vancomycin and ß-lactam antibiotics, as well as explore potential consequences of combination therapy.


Assuntos
Bacteriemia , Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Antibacterianos/uso terapêutico , Bacteriemia/tratamento farmacológico , Quimioterapia Combinada , Humanos , Estudos Prospectivos , Estudos Retrospectivos , Infecções Estafilocócicas/tratamento farmacológico , Vancomicina/uso terapêutico , beta-Lactamas/uso terapêutico
11.
J Contemp Dent Pract ; 21(11): 1284-1292, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-33850077

RESUMO

AIM AND OBJECTIVE: The aim of the present case report is to describe the digital management of an implant prosthetic rehabilitation performed by the use of different digital technologies, which allowed to successfully perform in 1 day both the surgical and the prosthetical stages with a minimally invasive approach and a high standard of care. BACKGROUND: Coronavirus disease-2019 (COVID-19) pandemic is affecting dental everyday practice. Clinicians have to reduce the number of patients per day and the time they spend in the dental office. Minimally invasive and digital approaches, with less possible exposure and interaction, are suggested to reduce the risk of infection. CASE DESCRIPTION: The failure of a short-span implant prosthetic rehabilitation combined with pain and mobility of the involved teeth was the main complaint reported by a 78-year-old male patient, who asked an urgent appointment to solve the problem. An intraoral scanner allowed the clinician to immediately take a preliminary digital impression of the arch to be treated. The resulting 3D files were sent by e-mail to the dental technician who provided a digital wax-up for the computerized workflow. Computer-aided implantology (CAI) performed using an in-office cone-beam computed tomography (CBCT) allowed clinician to guide the surgical approach in a prosthetic manner. Such an integration inside a well-defined workflow was the key for a successful and rapid treatment. CONCLUSION: By using new innovative digital technology, the treatment was completed in 1 day, reducing the risk of COVID-19 by limiting the number of appointments and reducing contacts in confined environments like the dental office and public transportations. It also helped to reduce materials production and people movement in the treatment of dental emergency. CLINICAL SIGNIFICANCE: The possibility of performing an effective treatment saving time by using efficient technology and a minimally invasive procedure highlights the importance of digital planning in order to optimize every single step of the treatment. Digital workflow reduces also the movement of potentially infected materials from the office to the dental laboratory.


Assuntos
COVID-19 , Desenho Assistido por Computador , Idoso , Tomografia Computadorizada de Feixe Cônico , Odontologia , Humanos , Masculino , SARS-CoV-2
12.
BMC Health Serv Res ; 19(1): 821, 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31703684

RESUMO

BACKGROUND: We have previously modelled that the optimal number of comprehensive stroke centres (CSC) providing endovascular thrombectomy (EVT) in England would be 30 (net 6 new centres). We now estimate the relative effectiveness and cost-effectiveness of increasing the number of centres from 24 to 30. METHODS: We constructed a discrete event simulation (DES) to estimate the effectiveness and lifetime cost-effectiveness (from a payer perspective) using 1 year's incidence of stroke in England. 2000 iterations of the simulation were performed comparing baseline 24 centres to 30. RESULTS: Of 80,800 patients admitted to hospital with acute stroke/year, 21,740 would be affected by the service reconfiguration. The median time to treatment for eligible early presenters (< 270 min since onset) would reduce from 195 (IQR 155-249) to 165 (IQR 105-224) minutes. Our model predicts reconfiguration would mean an additional 33 independent patients (modified Rankin scale [mRS] 0-1) and 30 fewer dependent/dead patients (mRS 3-6) per year. The net addition of 6 centres generates 190 QALYs (95%CI - 6 to 399) and results in net savings to the healthcare system of £1,864,000/year (95% CI -1,204,000 to £5,017,000). The estimated budget impact was a saving of £980,000 in year 1 and £7.07 million in years 2 to 5. CONCLUSION: Changes in acute stroke service configuration will produce clinical and cost benefits when the time taken for patients to receive treatment is reduced. Benefits are highly likely to be cost saving over 5 years before any capital investment above £8 million is required.


Assuntos
Procedimentos Endovasculares/economia , Acidente Vascular Cerebral/economia , Trombectomia/economia , Idoso , Instituições de Assistência Ambulatorial/economia , Orçamentos , Análise Custo-Benefício , Atenção à Saúde/economia , Inglaterra , Feminino , Hospitalização/economia , Hospitalização/estatística & dados numéricos , Hospitais/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Anos de Vida Ajustados por Qualidade de Vida , Medicina Estatal/economia , Acidente Vascular Cerebral/terapia , Trombectomia/métodos , Tempo para o Tratamento , Resultado do Tratamento
13.
Artigo em Inglês | MEDLINE | ID: mdl-29712661

RESUMO

Acute kidney injury (AKI) increases during empirical antimicrobial therapy with the combination of piperacillin-tazobactam (TZP) and vancomycin (VAN) compared to the number of incidences with monotherapy or the combination of cefepime and VAN. Limited data regarding the impact of meropenem (MEM) combined with VAN exist. This study examined the AKI incidence among patients treated with MEM plus VAN (MEM+VAN) or TZP+VAN. Data were collected from the University of Kentucky Center for Clinical and Translational Science Enterprise Data Trust from September 2007 through October 2015. Adults without previous renal disease who received MEM+VAN or TZP+VAN for at least 2 days were included. AKI was assessed using risk, injury, failure, loss, and end-stage (RIFLE) criteria. Inverse probability of treatment weighting was utilized to control for differences between groups. In total, 10,236 patients met inclusion criteria, with 9,898 receiving TZP+VAN and 338 receiving MEM+VAN. AKI occurred in 15.4% of MEM+VAN patients and in 27.4% of TZP+VAN patients (P < 0.001). TZP+VAN was associated with increased AKI compared to the level with MEM+VAN (odds ratio [OR], 2.53; 95% confidence interval [CI], 1.82 to 3.52), after controlling for confounders. Use of MEM+VAN should be considered an appropriate alternative therapy to TZP+VAN if nephrotoxicity is a major concern. The results of this study demonstrate that judicial use of TZP+VAN for empirical coverage of infection is needed.


Assuntos
Injúria Renal Aguda/induzido quimicamente , Antibacterianos/efeitos adversos , Meropeném/efeitos adversos , Combinação Piperacilina e Tazobactam/efeitos adversos , Vancomicina/efeitos adversos , Inibidores de beta-Lactamases/efeitos adversos , Adulto , Antibacterianos/uso terapêutico , Cefepima/efeitos adversos , Cefepima/uso terapêutico , Quimioterapia Combinada/efeitos adversos , Quimioterapia Combinada/métodos , Feminino , Humanos , Masculino , Meropeném/uso terapêutico , Pessoa de Meia-Idade , Combinação Piperacilina e Tazobactam/uso terapêutico , Estudos Retrospectivos , Vancomicina/uso terapêutico , Inibidores de beta-Lactamases/uso terapêutico
14.
Am J Med Genet A ; 176(1): 241-245, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29130632

RESUMO

Dedicator of cytokinesis (DOCK) family are evolutionary conserved guanine nucleotide exchange factors (GEFs) for the Rho GTPases, Rac, and Cdc42. DOCK3 functions as a GEF for Rac1, and plays an important role in promoting neurite and axonal growth by stimulating actin dynamics and microtubule assembly pathways in the central nervous system. Here we report a boy with developmental delay, hypotonia, and ataxia due to biallelic DOCK3 deletion. Chromosomal single nucleotide polymorphism (SNP) microarray analysis detected a 170 kb homozygous deletion including exons 6-12 of the DOCK3 gene at 3p21.2. Symptoms of our proband resembles a phenotype of Dock3 knockout mice exhibiting sensorimotor impairments. Furthermore, our proband has clinical similarities with two siblings with compound heterozygous loss-of-function mutations of DOCK3 reported in [Helbig, Mroske, Moorthy, Sajan, and Velinov (); https://doi.org/10.1111/cge.12995]. Biallelic DOCK3 mutations cause a neurodevelopmental disorder characterized by unsteady gait, hypotonia, and developmental delay.


Assuntos
Deficiências do Desenvolvimento/diagnóstico , Deficiências do Desenvolvimento/genética , Estudos de Associação Genética , Fatores de Troca do Nucleotídeo Guanina/genética , Mutação , Proteínas do Tecido Nervoso/genética , Alelos , Criança , Pré-Escolar , Fácies , Feminino , Genótipo , Humanos , Masculino , Fenótipo , Polimorfismo de Nucleotídeo Único , Deleção de Sequência
15.
Artigo em Inglês | MEDLINE | ID: mdl-28760891

RESUMO

Limited literature is available assessing nephrotoxicity with prolonged ß-lactam infusions. This study compared the incidence of acute kidney injury (AKI) associated with a prolonged ß-lactam infusion or an intermittent infusion. This was a retrospective, matched-cohort study at an academic medical center from July 2006 to September 2015. Adult patients who received piperacillin-tazobactam (TZP), cefepime (FEP), or meropenem (MEM) for at least 48 h were evaluated. Patients were excluded for preexisting renal dysfunction or pregnancy. The primary outcome was difference in incidence of AKI evaluated using the RIFLE (risk, injury, failure, loss, and end-stage) criteria. Patients in the intermittent group were matched 3:1 to patients in the prolonged-infusion group based on the following: ß-lactam agent, age, gender, Charlson comorbidity index, baseline creatinine clearance, hypotension, receipt of vancomycin, and treatment in an intensive care unit. A total of 2,390 patients were included in the matched analysis, with 1,700 receiving intermittent infusions and 690 receiving prolonged infusion. The incidence of AKI was similar in the prolonged-infusion group to that in the intermittent-infusion group (21.6% versus 18.6%; P = 0.1). After multivariate regression, prolonged infusion was not associated with increased odds of AKI (odds ratio [OR], 1.07; 95% confidence interval [95% CI], 0.83 to 1.39). Independent predictors of AKI included TZP therapy, concomitant nephrotoxins, hypotension, and heart failure. Although AKIs were numerically more common in patients receiving prolonged ß-lactam infusions than those receiving intermittent infusions, prolonged infusion was not an independent risk factor for AKI.


Assuntos
Injúria Renal Aguda/induzido quimicamente , Antibacterianos/efeitos adversos , Cefalosporinas/efeitos adversos , Ácido Penicilânico/análogos & derivados , Tienamicinas/efeitos adversos , Inibidores de beta-Lactamases/efeitos adversos , Injúria Renal Aguda/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/uso terapêutico , Cefepima , Cefalosporinas/uso terapêutico , Quimioterapia Combinada , Feminino , Humanos , Rim/efeitos dos fármacos , Rim/patologia , Masculino , Meropeném , Pessoa de Meia-Idade , Ácido Penicilânico/efeitos adversos , Ácido Penicilânico/uso terapêutico , Piperacilina/efeitos adversos , Piperacilina/uso terapêutico , Combinação Piperacilina e Tazobactam , Estudos Retrospectivos , Tienamicinas/uso terapêutico , Inibidores de beta-Lactamases/uso terapêutico
16.
Artigo em Inglês | MEDLINE | ID: mdl-28167560

RESUMO

Nephrotoxicity is the primary adverse effect of the polymyxins. The relative rates of toxicity of polymyxin B and colistin have not been fully elucidated, especially in patients with cystic fibrosis (CF). A retrospective cohort study of adults treated with polymyxin B or colistin for at least 48 h was conducted. The primary endpoint was the incidence of kidney injury assessed by RIFLE (i.e., risk, injury, failure, loss, end-stage renal disease) criteria. Risk factors for kidney injury were evaluated using multivariate Cox regression. A total of 414 patients were evaluated, 220 of whom had CF. In patients without CF, there was no difference in kidney injury with polymyxin B and colistin (42.9% versus 50.3%, P = 0.46). Loop diuretic exposure was a risk factor for kidney injury (adjusted hazard ratio [aHR], 1.82; 95% confidence interval [CI], 1.16 to 2.83) in this population. In patients with CF, polymyxin B and colistin were associated with similar rates of kidney injury (34.5% versus 29.8%, P = 0.77). Diabetes (aHR, 2.68; 95% CI, 1.01 to 7.11), loop diuretics (aHR, 3.02; 95% CI, 1.36 to 6.73), and progressive care unit admission (aHR, 8.21; 95% CI, 2.55 to 26.46) were risk factors for kidney injury, while higher baseline serum creatinine levels (per 1 mg/dl) were protective (aHR, 0.08; 95% CI, 0.01 to 0.48). Total unadjusted kidney injury in polymyxin-treated patients was less frequent in those who had CF (30.5% versus 48.5%, P < 0.001). Polymyxin B and colistin are associated with a high incidence of kidney injury; cystic fibrosis may be protective against polymyxin nephrotoxicity, but further investigation is needed to confirm this conjecture.


Assuntos
Injúria Renal Aguda/induzido quimicamente , Antibacterianos/efeitos adversos , Infecções Bacterianas/tratamento farmacológico , Colistina/efeitos adversos , Fibrose Cística/tratamento farmacológico , Polimixina B/efeitos adversos , Injúria Renal Aguda/sangue , Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/patologia , Adulto , Idoso , Antibacterianos/farmacocinética , Infecções Bacterianas/complicações , Infecções Bacterianas/microbiologia , Colistina/farmacocinética , Creatinina/sangue , Fibrose Cística/complicações , Fibrose Cística/microbiologia , Diabetes Mellitus/fisiopatologia , Feminino , Hospitalização , Humanos , Unidades de Terapia Intensiva , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , Masculino , Pessoa de Meia-Idade , Polimixina B/farmacocinética , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de Risco , Inibidores de Simportadores de Cloreto de Sódio e Potássio/efeitos adversos
17.
Artigo em Inglês | MEDLINE | ID: mdl-27895019

RESUMO

Recent reports have demonstrated that vancomycin (VAN) may lead to an increase in the incidence of acute kidney injury (AKI) when it is combined with antipseudomonal beta-lactams. This study compared the incidence of AKI associated with VAN plus piperacillin-tazobactam (TZP) or cefepime (FEP). This was a retrospective, matched cohort study that was conducted at an academic medical center between September 2010 and September 2014 and that included adult patients without severe chronic or structural kidney disease, dialysis, pregnancy, cystic fibrosis, or a hospital transfer receiving TZP-VAN or FEP-VAN for at least 48 h. The primary outcome was the difference in the AKI incidence between the TZP-VAN and FEP-VAN groups, evaluated using the risk, injury, failure, loss of kidney function, and end-stage kidney disease (RIFLE) criteria. Patients in the two groups were matched on the basis of age, sex, severity of illness, baseline creatinine clearance, hypotension, number of nephrotoxicity risk factors, and intravenous contrast exposure. In total, 4,193 patients met all inclusion criteria (3,605 received TZP-VAN and 588 received FEP-VAN). The unadjusted AKI incidence was 21.4% in patients receiving TZP-VAN, whereas it was 12.6% in patients receiving FEP-VAN (P < 0.001). After the patients were matched, 1,633 patients receiving TZP-VAN and 578 patients receiving FEP-VAN were evaluated. The AKI incidence remained higher in patients receiving TZP-VAN than in those receiving FEP-VAN (21.4% versus 12.5%, P < 0.0001). This trend remained true for all classifications of the RIFLE criteria. After controlling for remaining confounders, TZP-VAN therapy was associated with 2.18 times the odds of AKI than FEP-VAN therapy (95% confidence interval, 1.64 to 2.94 times) in logistic regression. AKI was significantly more common in patients receiving vancomycin in combination with piperacillin-tazobactam than in those receiving vancomycin in combination with cefepime. This finding reinforces the need for the judicious use of combination empirical antimicrobial therapy.


Assuntos
Cefalosporinas/efeitos adversos , Ácido Penicilânico/análogos & derivados , Vancomicina/efeitos adversos , Injúria Renal Aguda/induzido quimicamente , Adulto , Idoso , Antibacterianos/efeitos adversos , Antibacterianos/uso terapêutico , Cefepima , Cefalosporinas/uso terapêutico , Feminino , Humanos , Rim/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Ácido Penicilânico/efeitos adversos , Ácido Penicilânico/uso terapêutico , Piperacilina/efeitos adversos , Piperacilina/uso terapêutico , Combinação Piperacilina e Tazobactam , Estudos Retrospectivos , Vancomicina/uso terapêutico
19.
Nature ; 473(7347): 357-60, 2011 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-21508960

RESUMO

Mountain glaciers and ice caps are contributing significantly to present rates of sea level rise and will continue to do so over the next century and beyond. The Canadian Arctic Archipelago, located off the northwestern shore of Greenland, contains one-third of the global volume of land ice outside the ice sheets, but its contribution to sea-level change remains largely unknown. Here we show that the Canadian Arctic Archipelago has recently lost 61 ± 7 gigatonnes per year (Gt yr(-1)) of ice, contributing 0.17 ± 0.02 mm yr(-1) to sea-level rise. Our estimates are of regional mass changes for the ice caps and glaciers of the Canadian Arctic Archipelago referring to the years 2004 to 2009 and are based on three independent approaches: surface mass-budget modelling plus an estimate of ice discharge (SMB+D), repeat satellite laser altimetry (ICESat) and repeat satellite gravimetry (GRACE). All three approaches show consistent and large mass-loss estimates. Between the periods 2004-2006 and 2007-2009, the rate of mass loss sharply increased from 31 ± 8 Gt yr(-1) to 92 ± 12 Gt yr(-1) in direct response to warmer summer temperatures, to which rates of ice loss are highly sensitive (64 ± 14 Gt yr(-1) per 1 K increase). The duration of the study is too short to establish a long-term trend, but for 2007-2009, the increase in the rate of mass loss makes the Canadian Arctic Archipelago the single largest contributor to eustatic sea-level rise outside Greenland and Antarctica.

20.
Lancet ; 385 Suppl 2: S17, 2015 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-26313063

RESUMO

BACKGROUND: Trauma and road traffic accidents are predicted to increase significantly in the next decade in low-income and middle-income countries. The College of Surgeons of East, Central, and Southern Africa (COSECSA) covers Ethiopia, Kenya, Tanzania, Uganda, Rwanda, Burundi, Mozambique, Malawi, Zimbabwe, and Zambia. Ministry of Health websites for these ten countries show that 992 hospitals are covering an estimated 318 million people. METHODS: The WHO Tool for Situational Analysis to Assess Emergency and Essential Surgical Care was used with added questions relevant to trauma and orthopaedic care. A web-based survey platform was used and hospitals were contacted via COSECSA representatives. Consent to share data was requested, anonymised for country and hospital. FINDINGS: 267 (27%) of 992 hospitals completed the survey. 185 were district level hospitals and 82 were referral or tertiary level hospitals. Formal accident and emergency departments were present in only 29% of district hospitals (95% CI 22·5-35·5) and 35% (24·7-45·3) of referral or tertiary level hospitals. The mean number (SD) of surgeons was 1·4 (3·0) in district hospitals and 2·6 (4·6) in referral or tertiary level hospitals. The mean number (SD) of orthopaedic surgeons was 0·3 (0·9) in district hospitals and 0·5 (0·9) in referral or tertiary level hospitals. Medically qualified anaesthetists were available in 16% (95% CI 10·7-21·3) of district hospitals and 20% (11·4-28·6) of referral or tertiary level hospitals. C arm radiography was available in 3% (95% CI 0·5-5·5) of district hospitals and 32% (21·9-42·1) of referral or tertiary level hospitals. CT scanning was available in 6% (95% CI 2·6- 9·4) of district hospitals and 21% (12·2-29·8) of referral or tertiary level hospitals. Closed fracture treatment was offered in 75% (95% CI 68·8- 81·2) of district hospitals and 82% (73·7-90·3) of referral or tertiary level hospitals. 37% (95% CI 30·1-43·9) of district hospitals and 40% (29·4-50·6) of referral or tertiary level hospitals had adequate instruments for the surgical treatment of fractures, but only 7% (3·4-10·6) of district hospitals and 8% (2·1-13·9) of referral or tertiary level hospitals had a sustainable supply of fracture implants. Elective orthopaedic surgery took place in 30% (95% 23·4- 36·6) of district hospitals and 34% (23·8-44·2) of referral or tertiary level hospitals. Ponseti treatment of clubfoot was available at 46% (95% 38·8-53·2) of district hospitals and 44% (33·3-54·7) of referral or tertiary level hospitals. INTERPRETATION: This study has limitations in that only 27% of eligible hospitals completed the survey, and it is certainly possible that there could be bias in that the less well resourced institutions could also be less likely to cooperate with data collection. Thus, it is possible that the figures we present overestimate the resources available in the region as a whole. However, despite the limitations in data quality, it is clear that current capacity to treat trauma and orthopaedic conditions is very limited, with particular areas of concern being manpower, training, facilities, and equipment. COSECSA will use these data as a baseline for further surveys and to develop a strategy to improve trauma and orthopaedic care in the region. FUNDING: UK Department for International Development (DFID).

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