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1.
Anaesthesia ; 78(3): 294-302, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36562202

RESUMO

Reversing neuromuscular blockade with sugammadex can eliminate residual paralysis, which has been associated with postoperative respiratory complications. There are equivocal data on whether sugammadex reduces these when compared with neostigmine. We investigated the association of the choice of reversal drug with postoperative respiratory complications and advanced healthcare utilisation. We included adult patients who underwent surgery and received general anaesthesia with sugammadex or neostigmine reversal at two academic healthcare networks between January 2016 and June 2021. The primary outcome was postoperative respiratory complications, defined as post-extubation oxygen saturation < 90%, respiratory failure requiring non-invasive ventilation, or tracheal re-intubation within 7 days. Our main secondary outcome was advanced healthcare utilisation, a composite outcome including: 7-day unplanned intensive care unit admission; 30-day hospital readmission; or non-home discharge. In total, 5746 (6.9%) of 83,250 included patients experienced postoperative respiratory complications. This was not associated with the reversal drug (adjusted OR (95%CI) 1.01 (0.94-1.08); p = 0.76). After excluding patients admitted from skilled nursing facilities, 8372 (10.5%) patients required advanced healthcare utilisation, which was not associated with the choice of reversal (adjusted OR (95%CI) 0.95 (0.89-1.01); p = 0.11). Equivalence testing supported an equivalent effect size of sugammadex and neostigmine on both outcomes, and neostigmine was non-inferior to sugammadex with regard to postoperative respiratory complications or advanced healthcare utilisation. Finally, there was no association between the reversal drug and major adverse cardiovascular events (adjusted OR 1.07 (0.94-1.21); p = 0.32). Compared with neostigmine, reversal of neuromuscular blockade with sugammadex was not associated with a reduction in postoperative respiratory complications or post-procedural advanced healthcare utilisation.


Assuntos
Bloqueio Neuromuscular , Transtornos Respiratórios , Adulto , Humanos , Neostigmina/efeitos adversos , Sugammadex/efeitos adversos , Inibidores da Colinesterase/efeitos adversos , Estudos Retrospectivos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/prevenção & controle , Complicações Pós-Operatórias/induzido quimicamente , Transtornos Respiratórios/induzido quimicamente , Bloqueio Neuromuscular/efeitos adversos , Aceitação pelo Paciente de Cuidados de Saúde
2.
Anaesthesia ; 76(7): 962-973, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33170514

RESUMO

Postoperative nausea and vomiting is a common adverse effect of anaesthesia. Although dozens of different anti-emetics are available for clinical practice, there is currently no comparative ranking of efficacy and safety of these drugs to inform clinical practice. We performed a systematic review with network meta-analyses to compare, and rank in terms of efficacy and safety, single anti-emetic drugs and their combinations, including 5-hydroxytryptamine3 , dopamine-2 and neurokinin-1 receptor antagonists; corticosteroids; antihistamines; and anticholinergics used to prevent postoperative nausea and vomiting in adults after general anaesthesia. We systematically searched for placebo-controlled and head-to-head randomised controlled trials up to November 2017 (updated in April 2020). We assessed how trustworthy the evidence was using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) and Confidence In Network Meta-Analysis (CINeMA) approaches for vomiting within 24 h postoperatively, serious adverse events, any adverse event and drug class-specific side-effects. We included 585 trials (97,516 participants, 83% women) testing 44 single drugs and 51 drug combinations. The studies' overall risk of bias was assessed as low in only 27% of the studies. In 282 trials, 29 out of 36 drug combinations and 10 out of 28 single drugs lowered the risk of vomiting at least 20% compared with placebo. In the ranking of treatments, combinations of drugs were generally more effective than single drugs. Single neurokinin-1 receptor antagonists were as effective as other drug combinations. Out of the 10 effective single drugs, certainty of evidence was high for aprepitant, with risk ratio (95%CI) 0.26 (0.18-0.38); ramosetron, 0.44 (0.32-0.59); granisetron, 0.45 (0.38-0.54); dexamethasone, 0.51 (0.44-0.57); and ondansetron, 0.55 (0.51-0.60). It was moderate for fosaprepitant, 0.06 (0.02-0.21) and droperidol, 0.61 (0.54-0.69). Granisetron and amisulpride are likely to have little or no increase in any adverse event compared with placebo, while dimenhydrinate and scopolamine may increase the number of patients with any adverse event compared with placebo. So far, there is no convincing evidence that other single drugs effect the incidence of serious, or any, adverse events when compared with placebo. Among drug class specific side-effects, evidence for single drugs is mostly not convincing. There is convincing evidence regarding the prophylactic effect of at least seven single drugs for postoperative vomiting such that future studies investigating these drugs will probably not change the estimated beneficial effect. However, there is still considerable lack of evidence regarding safety aspects that does warrant investigation.


Assuntos
Anestesia Geral/efeitos adversos , Antieméticos/uso terapêutico , Náusea e Vômito Pós-Operatórios/prevenção & controle , Adulto , Feminino , Humanos , Masculino , Metanálise em Rede , Resultado do Tratamento
3.
Bioelectrochemistry ; 129: 54-61, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31103847

RESUMO

OBJECTIVE: The aim of this research was to investigate if dielectric spectroscopy between 100 Hz and 1 MHz provides reliable information about water distribution in ischaemic heart tissue and to investigate the influence of temperature on oedema formation. METHODS: We examined hearts of landrace piglets (n = 13) during ischaemia at 35 °C, 25 °C, and 15 °C. The dielectric permittivity ε'(f) and conductivity σ'(f) were calculated from impedance spectra measured between 100Hz and 1MHz. Gap junction uncoupling (GJU) was identified in the sigmoidal time course of ε'(13 kHz). The extracellular space index (ECSI) was estimated by the ratio σ'(100 Hz)/σ'(1 MHz). Intercalated water was analysed in electron microscopy images of the myocardial samples and was used to calculate the extracellular space index ECSIhisto. The ECSI and ECSIhisto were compared during ischaemia. GJU and oedema formation were simulated with an electrical heart model. RESULTS: At the onset of ischaemia, the ECSI was significantly higher than the ECSIhisto (p < .01). GJU during ischaemia was temperature-dependent. After GJU, the values of the ECSI and ECSIhisto matched very well. The simulations confirmed the influence of GJU on the ECSI. SIGNIFICANCE: The estimation of cell oedema with the ECSI is reliable only after GJU. The development of oedema estimated by the ECSI was delayed at cooler temperatures.


Assuntos
Espectroscopia Dielétrica/instrumentação , Edema Cardíaco/patologia , Isquemia Miocárdica/patologia , Miocárdio/patologia , Animais , Espectroscopia Dielétrica/métodos , Edema Cardíaco/etiologia , Desenho de Equipamento , Junções Comunicantes/patologia , Isquemia Miocárdica/complicações , Suínos
4.
Pharmazie ; 74(3): 186-190, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30961687

RESUMO

Medication refill reminder services (MRRS), having the potential to support the detection of non-adherence and to promote periodic medication refilling by addressing forgetfulness, are not generally available in community pharmacy practice. Based on a new software module, a MRRS was developed. The acceptance of this service was tested in community pharmacies in Germany. Patients were recruited by trained pharmacy staff. Supported by the software, the pharmacies reminded patients to refill their prescription. After 7 months, the service was evaluated by patients and pharmacy staff. The pharmacy owners/managers were interviewed. Ten pharmacies applied the service to 148 patients, with 806 refill reminders for 391 drugs. Seventy-five patients (50.7%) chose to be reminded by a phone call, followed by text message (n=25), and email (n=18). Of all patients, 75 (50.7%) completed the paper-based questionnaire. Sixty-eight (90.7%) rated the service as good or very good and 54 (72.0%) felt more satisfied with their pharmacy. Sixty-four patients (85.3%) considered the service as supportive and wanted to continue. Thirty-nine pharmacy staff members (61.9%) answered the online questionnaire. Twenty-four (61.5%) stated that they found it difficult to use and apply the MRRS; twenty-six (66.6%) experienced technical problems. The service was rated good by 16 (41.0%) pharmacy staff members. They regarded the service helpful for some patients and wanted to continue after the end of the study. The majority of the ten interviewed pharmacy owners/managers expressed the opinion that the service was not very suitable for increasing customer loyalty and not cost-effective. Nevertheless, six (60.0%) of them wanted to continue using the service. The MRRS seems to be feasible, apart from technical difficulties. Patients rated the service as supportive, and the personal contact seems to be of high importance; most patients would like to continue the service. However, offering the service to patients turned out to be challenging in daily German community pharmacy practice.


Assuntos
Serviços Comunitários de Farmácia/organização & administração , Sistemas de Registro de Ordens Médicas , Farmácias/organização & administração , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Alemanha , Humanos , Masculino , Adesão à Medicação , Pessoa de Meia-Idade , Aceitação pelo Paciente de Cuidados de Saúde , Farmacêuticos , Farmácia , Inquéritos e Questionários , Adulto Jovem
5.
Cell Calcium ; 78: 26-34, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30594060

RESUMO

The non-selective second messenger-gated cation channel TRPC6 (transient receptor potential canonical 6) is activated by diacylglycerols (DAG) in a PKC-independent manner and plays important roles in a variety of physiological processes and diseases. In order to facilitate novel therapies, the development of potent inhibitors as well as channel-activating agents is of great interest. The screening of a chemical library, comprising about 17,000 small molecule compounds, revealed an agent, which induced increases in intracellular Ca2+ concentrations ([Ca2+]i) in a concentration-dependent manner (EC50 = 2.37 ± 0.25 µM) in stably TRPC6-expressing HEK293 cells. This new compound (C20) selectively acts on TRPC6, unlike OAG (1-oleoyl-1-acetyl-sn-glycerol), which also activates PKC and does not discriminate between TRPC6 and the closely related channels TRPC3 and TRPC7. Further evaluation by Ca2+ assays and electrophysiological studies revealed that C20 rather operated as an enhancer of channel activation than as an activator by itself and led to the assumption that the compound C20 is an allosteric modulator of TRPC6, enabling low basal concentrations of DAG to induce activation of the ion channel. Furthermore, C20 was tested in human platelets that express TRPC6. A combined activation of TRPC6 with C20 and OAG elicited a robust increase in [Ca2+]i in human platelets. This potentiated channel activation was sensitive to TRPC6 channel blockers. To achieve sufficient amounts of C20 for biological studies, we applied a one-pot synthesis strategy. With regard to studies in native systems, the sensitizing ability of C20 can be a valuable pharmacological tool to selectively exaggerate TRPC6-dependent signals.


Assuntos
Cumarínicos/farmacologia , Bibliotecas de Moléculas Pequenas/farmacologia , Canal de Cátion TRPC6/agonistas , Regulação Alostérica/efeitos dos fármacos , Cálcio/análise , Cálcio/metabolismo , Células Cultivadas , Cumarínicos/síntese química , Cumarínicos/química , Fluorometria , Células HEK293 , Humanos , Bibliotecas de Moléculas Pequenas/síntese química , Bibliotecas de Moléculas Pequenas/química , Canal de Cátion TRPC6/metabolismo
6.
Br J Anaesth ; 120(6): 1394-1400, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29793604

RESUMO

BACKGROUND: The anaesthetic xenon shows potent organ-protective properties. Due to high density and dynamic viscosity, peak inspiratory pressure (Pmax) increases during xenon application. Thus, barotrauma may counteract organ protection. Accordingly, we investigated the influence of xenon on lung mechanics and lung aeration in patients with normal and reduced thoracic wall compliance. METHODS: After registration and ethical approval, 20 patients free of pulmonary disease undergoing routine xenon-based anaesthesia were mechanically ventilated. The primary outcome variable transpulmonary pressure (Ptp) was determined from plateau pressure and intraoesophageal pressure before and after xenon wash-in. We recorded Pmax, and calculated airway resistance (RAW), and static (Cstat) and dynamic (Cdyn) respiratory compliances. Finally, lung aeration was quantified by electrical impedance tomography-derived centre of ventilation index (CVI) and global inhomogeneity index (GI) in the awake state, before and during xenon. RESULTS: Xenon increased Pmax [20.8 (SD 3) vs 22.6 (3) cm H2O, P<0.001] and RAW [0.9 (0.2) vs 1.4 (0.3) cm H2O litre-1 s, P<0.001], without affecting Ptp [1.5 (4) vs 2.0 (4) cm H2O, P=0.15]. While Cstat remained unchanged, Cdyn was reduced [33.9 (7) vs 31.2 (6) ml (cm H2O)-1, P<0.001). A ventral tidal volume shift after anaesthesia induction [CVI 0.53 (0.03) vs 0.59 (0.04), P<0.001] was unaltered during xenon [CVI 0.59 (0.04), P=0.29]. Homogeneity of lung aeration was also unchanged during xenon [GI 0.37 (0.03) vs 0.37 (0.03), P=0.99]. There were no clinically meaningful differential BMI-related effects. CONCLUSIONS: Xenon increases calculated airway resistance and peak inspiratory pressure without affecting transpulmonary pressure, independent of BMI. CLINICAL TRIAL REGISTRATION: NCT02682758.


Assuntos
Anestésicos Inalatórios/farmacologia , Mecânica Respiratória/efeitos dos fármacos , Xenônio/farmacologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Resistência das Vias Respiratórias/efeitos dos fármacos , Índice de Massa Corporal , Feminino , Humanos , Inalação/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Propofol/farmacologia , Estudos Prospectivos , Respiração Artificial/métodos , Volume de Ventilação Pulmonar/efeitos dos fármacos , Adulto Jovem
7.
Br J Anaesth ; 120(1): 127-137, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29397119

RESUMO

BACKGROUND: Postoperative delirium occurs frequently in elderly hip fracture surgery patients and is associated with poorer overall outcomes. Because xenon anaesthesia has neuroprotective properties, we evaluated its effect on the incidence of delirium and other outcomes after hip fracture surgery. METHODS: This was a phase II, multicentre, randomized, double-blind, parallel-group, controlled clinical trial conducted in hospitals in six European countries (September 2010 to October 2014). Elderly (≥75yr-old) and mentally functional hip fracture patients were randomly assigned 1:1 to receive either xenon- or sevoflurane-based general anaesthesia during surgery. The primary outcome was postoperative delirium diagnosed through postoperative day 4. Secondary outcomes were delirium diagnosed anytime after surgery, postoperative sequential organ failure assessment (SOFA) scores, and adverse events (AEs). RESULTS: Of 256 enrolled patients, 124 were treated with xenon and 132 with sevoflurane. The incidence of delirium with xenon (9.7% [95% CI: 4.5 -14.9]) or with sevoflurane (13.6% [95% CI: 7.8 -19.5]) were not significantly different (P=0.33). Overall SOFA scores were significantly lower with xenon (least-squares mean difference: -0.33 [95% CI: -0.60 to -0.06]; P=0.017). For xenon and sevoflurane, the incidence of serious AEs and fatal AEs was 8.0% vs 15.9% (P=0.05) and 0% vs 3.8% (P=0.06), respectively. CONCLUSIONS: Xenon anaesthesia did not significantly reduce the incidence of postoperative delirium after hip fracture surgery. Nevertheless, exploratory observations concerning postoperative SOFA-scores, serious AEs, and deaths warrant further study of the potential benefits of xenon anaesthesia in elderly hip fracture surgery patients. CLINICAL TRIAL REGISTRATION: EudraCT 2009-017153-35; ClinicalTrials.gov NCT01199276.


Assuntos
Anestésicos Inalatórios , Delírio do Despertar/psicologia , Fraturas do Quadril/cirurgia , Xenônio , Idoso , Idoso de 80 Anos ou mais , Anestesia por Inalação , Delírio do Despertar/epidemiologia , Feminino , Fraturas do Quadril/mortalidade , Humanos , Incidência , Masculino , Procedimentos Ortopédicos/efeitos adversos , Procedimentos Ortopédicos/mortalidade , Estudos Prospectivos , Sevoflurano , Resultado do Tratamento
9.
Mar Environ Res ; 130: 122-133, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28756908

RESUMO

Bait collection is a multibillion dollar worldwide activity that is often managed ineffectively. For managers to understand the impacts on protected inter-tidal mudflats and waders at appropriate spatial scales macrofaunal surveys combined with video recordings of birds and bait collectors were undertaken at two UK sites. Dug sediment constituted approximately 8% of the surveyed area at both sites and is less muddy (lower organic content) than undug sediment. This may have significant implications for turbidity. Differences in the macrofaunal community between dug and undug areas if the same shore height is compared as well as changes in the dispersion of the community occurred at one site. Collection also induces a 'temporary loss of habitat' for some birds as bait collector numbers negatively correlate with wader and gull abundance. Bait collection changes the coherence and ecological structure of inter-tidal mudflats as well as directly affecting wading birds. However, as ß diversity increased we suggest that management at appropriate hectare/site scales could maximise biodiversity/function whilst still supporting collection.


Assuntos
Biodiversidade , Aves , Ecossistema , Animais , Ecologia
10.
Cell Mol Biol (Noisy-le-grand) ; 63(5): 119-126, 2017 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-28719356

RESUMO

Polymorphonuclear granulocytes (PMN) are activated in inflammatory reactions. Intestinal epithelial cells are relevant for maintaining the intestinal barrier. We examined interactions of PMN and intestinal epithelial cell-like CaCo-2 cells to elucidate their regulation of inflammatory signalling and the impact of cyclooxygenase (COX), nitric oxide (NO) and platelet-activating factor (PAF). Human PMN and CaCo-2 cells, separately and in co-incubation, were stimulated with the calcium ionophore A23187 or with N-Formyl-methionyl-leucyl-phenylalanin (fMLP) that activates PMN only. Human neutrophil elastase (HNE) and respiratory Burst were measured. To evaluate the modulation of inflammatory crosstalk we applied inhibitors of COX (acetyl salicylic acid; ASA), NO-synthase (N-monomethyl-L-arginin; L-NMMA), and the PAF-receptor (WEB2086). Unstimulated, co-incubation of CaCo-2 cells and PMN led to significantly reduced Burst and elevated HNE as compared to PMN. After stimulation with A23187, co-incubation resulted in an inhibition of Burst and HNE. Using fMLP co-incubation failed to modulate Burst but increased HNE. Without stimulation, all three inhibitors abolished the effect of co-incubation on Burst but did not change HNE.  ASA partly prevented modulation of Burst L-NMMA and WEB2086 did not change Burst but abolished mitigation of HNE. Without stimulation, co-incubation reduced Burst and elevated HNE. Activation of PMN and CaCo-2 cells by fMLP as compared to A23187 resulted in a completely different pattern of Burst and HNE, possibly due to single vs. dual cell activation. Anti-inflammatory effect of co-incubation might in part be due to due to COX-signalling governing Burst whereas NO- and PAF-dependent signalling seemed to control HNE release.


Assuntos
Inflamação/patologia , Neutrófilos/metabolismo , Neutrófilos/patologia , Aspirina/farmacologia , Azepinas/farmacologia , Células CACO-2 , Calcimicina/farmacologia , Humanos , N-Formilmetionina Leucil-Fenilalanina/farmacologia , Neutrófilos/efeitos dos fármacos , Elastase Pancreática/metabolismo , Explosão Respiratória/efeitos dos fármacos , Triazóis/farmacologia , ômega-N-Metilarginina/farmacologia
11.
Anaesthesist ; 66(9): 660-666, 2017 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-28589374

RESUMO

BACKGROUND: One of the prime aims of intensive care is to cure patients or at least to extend life duration, sometimes to the extent of losing quality of life. Palliative care aims to improve the quality of life of patients with life-limiting conditions; however, some patients need both intensive and palliative care. About 5-10% of all deaths in Germany and 20% of all deaths in the USA occur in an intensive care unit (ICU) and many of those as well as other patients may benefit from palliative care consultation. Palliative care consultations are increasingly available for intensive care patients but are still infrequently used. OBJECTIVES: We aimed to determine the current situation of palliative patients in ICU settings: what is the impact of palliative care interventions on the quality of care of ICU patients? To what extent is palliative care support at ICUs available and to what extent is it used? Which factors trigger palliative care consultations? METHOD: We set out with a search of PubMed, Scopus and other databases in English and on a) the impact of palliative care interventions on the quality of care of ICU patients, b) the utilization of palliative care support in ICUs and c) the factors which trigger palliative care consultations. We included both quantitative and qualitative studies to reflect the views of all parties involved. To emphasize the situation in German-speaking countries we also searched Google Scholar with search terms in German and added those results to the review. Additionally, hand-searched studies in English and in German were included. RESULTS: We screened 695 abstracts and identified 18 relevant articles of which 15 were from the USA and Great Britain, 1 each was from Austria, Germany and Switzerland. Palliative care is a meaningful addition to ICU standard treatment: it can improve quality of care and helps reduce length of stay in an ICU. It is unclear if the reduced length of stay leads to economic benefits; however, the utilization of palliative care is inconsistent and infrequent as is its acceptance among ICU physicians. Trigger factors can be used to improve the integration of palliative care support in ICUs and point out patients' unmet palliative needs. DISCUSSION: Trigger factors can reduce barriers which hold back the integration of palliative care in ICUs. Early integration of palliative care can improve quality of care by offering psychological support to patients and their families and by providing collegial consultation. An ongoing prospective study is investigating the acceptance of trigger factors in the daily routine among ICU physicians in Germany.


Assuntos
Cuidados Críticos/organização & administração , Cuidados Paliativos/organização & administração , Cuidados Críticos/métodos , Humanos , Medicina Integrativa , Cuidados Paliativos/métodos , Encaminhamento e Consulta
12.
Science ; 353(6303)2016 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-27701087

RESUMO

Volcanic edifices are abundant on rocky bodies of the inner solar system. In the cold outer solar system, volcanism can occur on solid bodies with a water-ice shell, but derived cryovolcanic constructs have proved elusive. We report the discovery, using Dawn Framing Camera images, of a landform on dwarf planet Ceres that we argue represents a viscous cryovolcanic dome. Parent material of the cryomagma is a mixture of secondary minerals, including salts and water ice. Absolute model ages from impact craters reveal that extrusion of the dome has occurred recently. Ceres' evolution must have been able to sustain recent interior activity and associated surface expressions. We propose salts with low eutectic temperatures and thermal conductivities as key drivers for Ceres' long-term internal evolution.

14.
Nature ; 528(7581): 237-40, 2015 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-26659183

RESUMO

The dwarf planet (1) Ceres, the largest object in the main asteroid belt with a mean diameter of about 950 kilometres, is located at a mean distance from the Sun of about 2.8 astronomical units (one astronomical unit is the Earth-Sun distance). Thermal evolution models suggest that it is a differentiated body with potential geological activity. Unlike on the icy satellites of Jupiter and Saturn, where tidal forces are responsible for spewing briny water into space, no tidal forces are acting on Ceres. In the absence of such forces, most objects in the main asteroid belt are expected to be geologically inert. The recent discovery of water vapour absorption near Ceres and previous detection of bound water and OH near and on Ceres (refs 5-7) have raised interest in the possible presence of surface ice. Here we report the presence of localized bright areas on Ceres from an orbiting imager. These unusual areas are consistent with hydrated magnesium sulfates mixed with dark background material, although other compositions are possible. Of particular interest is a bright pit on the floor of crater Occator that exhibits probable sublimation of water ice, producing haze clouds inside the crater that appear and disappear with a diurnal rhythm. Slow-moving condensed-ice or dust particles may explain this haze. We conclude that Ceres must have accreted material from beyond the 'snow line', which is the distance from the Sun at which water molecules condense.

15.
Transplant Proc ; 47(8): 2425-32, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26518945

RESUMO

The risk of rejection by cellular alloreactivity to the transplant donor is not routinely assessed. Here we analyzed alloreactive T cells in kidney transplant recipients and report how their detection may have helped to prevent rejection of a second kidney graft in a patient with a history of acute accelerated steroid-resistant nonhumoral rejection. Alloreactive CD4 and CD8 T cells were quantified using a flow-cytometric mixed lymphocyte reaction assay based on interferon-γ induction. A group of 16 nonrejecting transplant recipients did not show any alloreactive T-cell immunity to their respective donors, whereas alloreactivity to third-party controls was detectable. In the patient with rejection, HLA-specific antibodies were not detectable before and shortly after rejection, but after transplantation the patient showed exceptionally high frequencies of alloreactive T cells against 2 of 11 HLA-typed controls (0.604% and 0.791% alloreactive CD4 T cells and 0.792% and 0.978% alloreactive CD8 T cells) who shared HLA alleles (HLA-A*24, -B*44, -C*02, -DQB1*5) with the kidney donor. These HLA alleles were subsequently excluded for allocation of a second graft. No alloreactive T cells were observed toward the second kidney donor, and this transplantation was performed successfully. Thus, shared HLA alleles between the donor and third-party controls may suggest that alloreactive T cells had contributed to rejection of the first graft. The rejecting patient highlights that determination of cellular alloreactivity before transplantation may be applied to identify unacceptable mismatches and to reduce the risk for acute cellular rejection episodes.


Assuntos
Rejeição de Enxerto/imunologia , Antígenos HLA/fisiologia , Falência Renal Crônica/cirurgia , Transplante de Rim , Linfócitos T/fisiologia , Adulto , Estudos de Casos e Controles , Feminino , Citometria de Fluxo , Teste de Histocompatibilidade , Humanos , Falência Renal Crônica/imunologia , Teste de Cultura Mista de Linfócitos , Masculino , Pessoa de Meia-Idade , Reoperação , Risco
16.
Br J Anaesth ; 115(1): 61-7, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25962612

RESUMO

BACKGROUND: In contrast to volatile anaesthetics, xenon acts by antagonism at N-methyl-d-aspartate receptors and antagonizes 5-hydroxytryptamine type 3 receptors that mediate nausea and vomiting. Therefore, it is unknown whether the same risk factors for postoperative nausea and vomiting (PONV) after volatile anaesthetics apply to xenon-based anaesthesia. METHODS: With ethics committee approval and written informed consent, 502 consecutive patients undergoing xenon-based anaesthesia were included in a multicentre prospective observational study. Antiemetic prophylaxis was administered at the discretion of the attending anaesthetists. Postoperative nausea and vomiting and need for antiemetic rescue medication were assessed for 24 h after anaesthesia. Multivariate logistic regression analysis was performed to quantify risk factors for PONV and need for rescue medication. RESULTS: Four hundred and eighty-eight subjects were available for the final analysis. The incidence of PONV in subjects without prophylaxis was lower than expected according to the Apfel Score (28% observed; 42% expected, P<0.001). Independent predictors for PONV were (adjusted odds ratio; 95% confidence interval) female sex (1.76; 1.08-2.89), younger patient age (0.82 per 10 yr; 0.69-0.97), and longer duration of anaesthesia (1.36 per hour; 1.17-1.59). CONCLUSIONS: The incidence of PONV was significantly lower than predicted by the Apfel Score. Female sex, younger age, and longer duration of anaesthesia are risk factors for PONV after xenon-based anaesthesia. CLINICAL TRIAL REGISTRATION: German Federal Institute for Drugs and Medical Devices number AL-PMS-01/07GER.


Assuntos
Anestésicos Inalatórios/efeitos adversos , Náusea e Vômito Pós-Operatórios/induzido quimicamente , Náusea e Vômito Pós-Operatórios/epidemiologia , Xenônio/efeitos adversos , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Feminino , Alemanha/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Fatores Sexuais , Fatores de Tempo , Adulto Jovem
17.
Basic Res Cardiol ; 110(2): 5, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25600224

RESUMO

The sustained component of the K(+) outward current in human atrial myocytes is believed to be due to the slowly inactivating ultra-rapid potassium current I Kur and not to the fast inactivating transient outward current Ito. Here we provide evidence for contribution of Ito to this late current due to the effects of dipeptidyl peptidase-like protein (DPP) 10 (DPP10a) interacting with Kv4.3 channels. We studied the late current component of Ito in human atrial myocytes and CHO cells co-expressing Kv4.3 or Kv4.3/KChIP2 (control) and DPP proteins using voltage-clamp technique and a pharmacological approach. A voltage dependent and slowly inactivating late current (43% of peak amplitude) could be observed in atrial myocytes. We found a similar current in CHO cells expressing Kv4.3/KChIP2 + DPP10a, but not in cells co-expressing Kv4.3 + DPP or Kv4.3/KChIP2 + DPP6-S. Assuming that DPP10a influences atrial Ito, we detected DPP10 expression of three alternatively spliced mRNAs, DPP10 protein and colocalization of Kv4.3 and DPP10 proteins in human atrial myocytes. DPP10a did not affect properties of expressed Kv1.5 excluding a contribution to the sustained IKur in atrial cells. To test for the contribution of Kv4-based Ito on sustained K(+) outward currents in human atrial myocytes, we used 4-AP to block IKur, in combination with Heteropoda toxin 2 to block Kv4 channels. We could clearly separate an Ito fraction of about 19% contributing to the late current in atrial myocytes. Thus, the interaction of DPP10a, expressed in human atrium, with Kv4.3 channels generates a sustained current component of Ito, which may affect late repolarization phase of atrial action potentials.


Assuntos
Potenciais de Ação/fisiologia , Dipeptidil Peptidases e Tripeptidil Peptidases/metabolismo , Miócitos Cardíacos/metabolismo , Canais de Potássio Shal/metabolismo , Idoso , Idoso de 80 Anos ou mais , Animais , Células CHO , Cricetulus , Feminino , Imunofluorescência , Átrios do Coração/metabolismo , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Técnicas de Patch-Clamp , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção
18.
Sci Rep ; 4: 6575, 2014 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-25300652

RESUMO

Cocrystals, solid mixtures of different molecules on molecular scale, are supposed to be tailor made materials with improved employability compared to their pristine individual components in domains such as medicine and explosives. In medicine, cocrystals are obtained by crystallization of active pharmaceutical ingredients with precisely chosen coformers to design medicaments that demonstrate enhanced stability, high solubility, and therefore high bioavailability and optimized drug up-take. Nanoscaling may further advance these characteristica compared to their micronsized counterparts - because of a larger surface to volume ratio of nanoparticles. In the field of energetic materials, cocrystals offer the opportunity to design smart explosives, combining high reactivity with significantly reduced sensitivity, nowadays essential for a safe manipulation and handling. Furthermore, cocrystals are used in ferroelectrics, non-linear material response and electronic organics. However, state of the art batch processes produce low volume of cocrystals of variable quality and only have produced micronsized cocrystals so far, no nano-cocrystals. Here we demonstrate the continuous preparation of pharmaceutical and energetic micro- and nano-cocrystals using the Spray Flash Evaporation process. Our laboratory scale pilot plant continuously prepared up to 8 grams per hour of Caffeine/Oxalic acid 2:1, Caffeine/Glutaric acid 1:1, TNT/CL-20 1:1 and HMX/Cl-20 1:2 nano- and submicronsized cocrystals.


Assuntos
Cafeína/química , Cristalização , Nanopartículas/química , Estabilidade de Medicamentos , Glutaratos/química , Ligação de Hidrogênio , Solubilidade , Difração de Raios X
19.
J Pharmacol Exp Ther ; 350(3): 531-42, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24970925

RESUMO

Tanshinone II A sulfonate (TIIAS) was identified as a potent, selective blocker of purinergic receptor P2X7 in a compound library screen. In this study, a detailed characterization of the pharmacologic effects of TIIAS on P2X7 is provided. Because TIIAS is a derivative of tanshinone II A (TIIA) and both compounds have been used interchangeably, TIIA was included in some assays. Fluorometric and electrophysiologic assays were used to characterize effects of TIIAS and TIIA on recombinantly expressed human, rat, and mouse P2X7. Results were confirmed in human monocyte-derived macrophages expressing native P2X7. In all experiments, involvement of P2X7 was verified using established P2X7 antagonists. TIIAS, but not TIIA, reduces Ca(2+) influx via human P2X7 (hP2X7) with an IC50 of 4.3 µM. TIIAS was less potent at mouse P2X7 and poorly inhibited rat P2X7. Monitoring of YO-PRO-1 uptake confirmed these findings, indicating that formation of the hP2X7 pore is also suppressed by TIIAS. Electrophysiologic experiments revealed a noncompetitive mode of action. TIIAS time-dependently inhibits hP2X7 gating, possibly by binding to the intracellular domain of the receptor. Inhibition of native P2X7 in macrophages by TIIAS was confirmed by monitoring Ca(2+) influx, YO-PRO-1 uptake, and release of the proinflammatory cytokine interleukin-1ß. Fluorometric experiments involving recombinantly expressed rat P2X2 and human P2X4 were conducted and verified the compound's selectivity. Our data suggest that hP2X7 is a molecular target of TIIAS, but not of TIIA, a compound with different pharmacologic properties.


Assuntos
Abietanos/farmacologia , Fenantrenos/farmacologia , Antagonistas do Receptor Purinérgico P2X/farmacologia , Receptores Purinérgicos P2X7/fisiologia , Abietanos/química , Animais , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Células HEK293 , Humanos , Camundongos , Fenantrenos/química , Antagonistas do Receptor Purinérgico P2X/química , Ratos
20.
J Mol Cell Cardiol ; 56: 8-18, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23291429

RESUMO

In human atrial myocytes the transient outward current I(to) develops a conspicuous faster inactivation with increasing temperatures. Since ß-subunits are known to modulate I(to) current kinetics, we hypothesized that the temperature sensitivity of I(to) is not only determined by the property of the ion-passing α-subunit Kv4.3 but also by its interaction with accessory ß-subunits. We therefore studied the influence of the transmembrane ß-subunits KCNE1, KCNE2 and DPP6 on Kv4.3/KChIP2 channels in CHO cells at room temperature and at physiological temperature. Exposure to 37°C caused a significant acceleration of the channel kinetics, whereas current densities and voltage dependences remained unaltered at 37°C compared to 23°C. However, Kv4.3/KChIP2 channels without transmembrane ß-subunits showed the strongest temperature sensitivity with considerably increased rates of activation and inactivation at 37°C. KCNE2 significantly slowed the current kinetics at 37°C compared to Kv4.3/KChIP2 channels, whereas KCNE1 did not influence the channel properties at both temperatures. Interestingly, the accelerating effects of DPP6 on current kinetics described at 23°C were diminished at physiological temperature, thus at 37°C current kinetics became remarkably similar for channel complexes Kv4.3/KChIP2 with and without DPP6 isoforms. A Markov state model was developed on the basis of experimental measurements to simulate the influence of ß-subunits on Kv4.3 channel complex at both temperatures. In conclusion, the remarkably fast kinetics of the native I(to) at 37°C could be reproduced by co-expressing Kv4.3, KChIP2, KCNE2 and DPP6 in CHO cells, whereas the high temperature sensitivity of human I(to) could be not mimicked.


Assuntos
Subunidades Proteicas/fisiologia , Canais de Potássio Shal/metabolismo , Potenciais de Ação , Animais , Células CHO , Cricetinae , Dipeptidil Peptidases e Tripeptidil Peptidases/fisiologia , Humanos , Ativação do Canal Iônico , Cinética , Cadeias de Markov , Modelos Biológicos , Proteínas do Tecido Nervoso/fisiologia , Técnicas de Patch-Clamp , Canais de Potássio/fisiologia , Canais de Potássio de Abertura Dependente da Tensão da Membrana/fisiologia , Estabilidade Proteica , Termodinâmica
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