Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 267
Filtrar
Más filtros

País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Proc Natl Acad Sci U S A ; 119(3)2022 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-35017303

RESUMEN

Anaerobic microbial respiration in suboxic and anoxic environments often involves particulate ferric iron (oxyhydr-)oxides as terminal electron acceptors. To ensure efficient respiration, a widespread strategy among iron-reducing microorganisms is the use of extracellular electron shuttles (EES) that transfer two electrons from the microbial cell to the iron oxide surface. Yet, a fundamental understanding of how EES-oxide redox thermodynamics affect rates of iron oxide reduction remains elusive. Attempts to rationalize these rates for different EES, solution pH, and iron oxides on the basis of the underlying reaction free energy of the two-electron transfer were unsuccessful. Here, we demonstrate that broadly varying reduction rates determined in this work for different iron oxides and EES at varying solution chemistry as well as previously published data can be reconciled when these rates are instead related to the free energy of the less exergonic (or even endergonic) first of the two electron transfers from the fully, two-electron reduced EES to ferric iron oxide. We show how free energy relationships aid in identifying controls on microbial iron oxide reduction by EES, thereby advancing a more fundamental understanding of anaerobic respiration using iron oxides.


Asunto(s)
Electrones , Espacio Extracelular/química , Compuestos Férricos/química , Bases de Datos como Asunto , Compuestos de Hierro/química , Minerales/química , Termodinámica
2.
J Am Chem Soc ; 146(18): 12645-12655, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38651821

RESUMEN

The increased production of plastics is leading to the accumulation of plastic waste and depletion of limited fossil fuel resources. In this context, we report a strategy to create polymers that can undergo controlled depolymerization by linking renewable feedstocks with siloxane bonds. α,ω-Diesters and α,ω-diols containing siloxane bonds were synthesized from an alkenoic ester derived from castor oil and then polymerized with varied monomers, including related biobased monomers. In addition, cyclic monomers derived from this alkenoic ester and hydrosiloxanes were prepared and cyclized to form a 26-membered macrolactone containing a siloxane unit. Sequential ring-opening polymerization of this macrolactone and lactide afforded an ABA triblock copolymer. This set of polymers containing siloxanes underwent programmed depolymerization into monomers in protic solvents or with hexamethyldisiloxane and an acid catalyst. Monomers afforded by the depolymerization of polyesters containing siloxane linkages were repolymerized to demonstrate circularity in select polymers. Evaluation of the environmental stability of these polymers toward enzymatic degradation showed that they undergo enzymatic hydrolysis by a fungal cutinase from Fusarium solani. Evaluation of soil microbial metabolism of monomers selectively labeled with 13C revealed differential metabolism of the main chain and side chain organic groups by soil microbes.


Asunto(s)
Fusarium , Polimerizacion , Siloxanos , Siloxanos/química , Aceites de Plantas/química , Polímeros/química , Estructura Molecular , Hidrolasas de Éster Carboxílico
3.
Anesthesiology ; 141(3): 443-452, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38557791

RESUMEN

BACKGROUND: The Hypotension Prediction Index (the index) software is a machine learning algorithm that detects physiologic changes that may lead to hypotension. The original validation used a case control (backward) analysis that has been suggested to be biased. This study therefore conducted a cohort (forward) analysis and compared this to the original validation technique. METHODS: A retrospective analysis of data from previously reported studies was conducted. All data were analyzed identically with two different methodologies, and receiver operating characteristic curves were constructed. Both backward and forward analyses were performed to examine differences in area under the receiver operating characteristic curves for the Hypotension Prediction Index and other hemodynamic variables to predict a mean arterial pressure (MAP) less than 65 mmHg for at least 1 min 5, 10, and 15 min in advance. RESULTS: The analysis included 2,022 patients, yielding 4,152,124 measurements taken at 20-s intervals. The area under the curve for the index predicting hypotension analyzed by backward and forward methodologies respectively was 0.957 (95% CI, 0.947 to 0.964) versus 0.923 (95% CI, 0.912 to 0.933) 5 min in advance, 0.933 (95% CI, 0.924 to 0.942) versus 0.923 (95% CI, 0.911 to 0.933) 10 min in advance, and 0.929 (95% CI, 0.918 to 0.938) versus 0.926 (95% CI, 0.914 to 0.937) 15 min in advance. No variable other than MAP had an area under the curve greater than 0.7. The areas under the curve using forward analysis for MAP predicting hypotension 5, 10, and 15 min in advance were 0.932 (95% CI, 0.920 to 0.940), 0.929 (95% CI, 0.918 to 0.938), and 0.932 (95% CI, 0.921 to 0.940), respectively. The R2 for the variation in the index due to MAP was 0.77. CONCLUSIONS: Using an updated methodology, the study found that the utility of the Hypotension Prediction Index to predict future hypotensive events is high, with an area under the receiver operating characteristics curve similar to that of the original validation method.


Asunto(s)
Hipotensión , Humanos , Hipotensión/diagnóstico , Hipotensión/fisiopatología , Estudios Retrospectivos , Estudios de Casos y Controles , Masculino , Femenino , Estudios de Cohortes , Valor Predictivo de las Pruebas , Aprendizaje Automático , Persona de Mediana Edad , Curva ROC , Algoritmos
4.
Clin Transplant ; 38(9): e15457, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39282762

RESUMEN

BACKGROUND: Post-lung transplantation (LTx) fluid accumulation can lead to dilution of serum creatinine (SCr). We hypothesized that fluid accumulation might impact the diagnosis, staging, and outcome of posttransplant acute kidney injury (AKI). METHODS: In this retrospective study, we analyzed data from 131 adult LTx patients at a single German lung center between 2005 and 2018. We assessed the occurrence of AKI within 7 days posttransplant, both before and after SCr-adjustment for fluid balance (FB), and investigated its impact on all-cause mortality. Transient and persistent AKIs were defined as return to baseline kidney function or continuation of AKI beyond 72 h of onset, respectively. RESULTS: AKI was diagnosed in 58.8% of patients according to crude SCr values. When considering FB-adjusted SCr values, AKI severity was underestimated in 20.6% of patients, that is, AKI was detected in an additional 6.9% of patients and led to AKI upstaging in 23.4% of cases. Patients initially underestimated but detected with AKI only after FB adjustment had higher mortality compared to those who did not meet AKI criteria (hazard ratio [HR] 2.98; 95% confidence interval [CI] 1.06, 8.36; p = 0.038). Persistent AKI was associated with higher mortality than transient AKI, regardless of using crude or adjusted SCr values (p < 0.05). Persistent AKI emerged as an independent risk factor for mortality (HR 2.35; 95% CI 1.29, 4.30; p = 0.005). CONCLUSION: Adjusting for FB and evaluating renal recovery patterns post-AKI may enhance the sensitivity of AKI detection. This approach could help identify patients with poor prognosis and potentially improve outcomes in lung transplant recipients. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT03039959, NCT03046277.


Asunto(s)
Lesión Renal Aguda , Trasplante de Pulmón , Complicaciones Posoperatorias , Humanos , Masculino , Femenino , Trasplante de Pulmón/efectos adversos , Estudios Retrospectivos , Lesión Renal Aguda/etiología , Lesión Renal Aguda/diagnóstico , Persona de Mediana Edad , Pronóstico , Complicaciones Posoperatorias/diagnóstico , Estudios de Seguimiento , Factores de Riesgo , Tasa de Supervivencia , Tasa de Filtración Glomerular , Adulto , Receptores de Trasplantes , Índice de Severidad de la Enfermedad , Supervivencia de Injerto , Creatinina/sangre
5.
Infection ; 52(2): 413-427, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37684496

RESUMEN

PURPOSE: Timely and accurate data on the epidemiology of sepsis are essential to inform policy decisions and research priorities. We aimed to investigate the validity of inpatient administrative health data (IAHD) for surveillance and quality assurance of sepsis care. METHODS: We conducted a retrospective validation study in a disproportional stratified random sample of 10,334 inpatient cases of age ≥ 15 years treated in 2015-2017 in ten German hospitals. The accuracy of coding of sepsis and risk factors for mortality in IAHD was assessed compared to reference standard diagnoses obtained by a chart review. Hospital-level risk-adjusted mortality of sepsis as calculated from IAHD information was compared to mortality calculated from chart review information. RESULTS: ICD-coding of sepsis in IAHD showed high positive predictive value (76.9-85.7% depending on sepsis definition), but low sensitivity (26.8-38%), which led to an underestimation of sepsis incidence (1.4% vs. 3.3% for severe sepsis-1). Not naming sepsis in the chart was strongly associated with under-coding of sepsis. The frequency of correctly naming sepsis and ICD-coding of sepsis varied strongly between hospitals (range of sensitivity of naming: 29-71.7%, of ICD-diagnosis: 10.7-58.5%). Risk-adjusted mortality of sepsis per hospital calculated from coding in IAHD showed no substantial correlation to reference standard risk-adjusted mortality (r = 0.09). CONCLUSION: Due to the under-coding of sepsis in IAHD, previous epidemiological studies underestimated the burden of sepsis in Germany. There is a large variability between hospitals in accuracy of diagnosing and coding of sepsis. Therefore, IAHD alone is not suited to assess quality of sepsis care.


Asunto(s)
Hospitales , Sepsis , Humanos , Adolescente , Estudios Retrospectivos , Mortalidad Hospitalaria , Sepsis/diagnóstico , Sepsis/epidemiología , Sesgo
6.
Environ Sci Technol ; 58(2): 1274-1286, 2024 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-38164921

RESUMEN

Water-soluble polymers (WSPs) are used in diverse applications, including agricultural formulations, that can result in the release of WSPs to soils. WSP biodegradability in soils is desirable to prevent long-term accumulation and potential associated adverse effects. In this work, we assessed adsorption of five candidate biodegradable WSPs with varying chemistry, charge, and polarity characteristics (i.e., dextran, diethylaminoethyl dextran, carboxymethyl dextran, polyethylene glycol monomethyl ether, and poly-l-lysine) and of one nonbiodegradable WSP (poly(acrylic acid)) to sand and iron oxide-coated sand particles that represent important soil minerals. Combined adsorption studies using solution-depletion measurements, direct surface adsorption techniques, and column transport experiments over varying solution pH and ionic strengths revealed electrostatics dominating interactions of charged WSPs with the sorbents as well as WSP conformations and packing densities in the adsorbed states. Hydrogen bonding controls adsorption of noncharged WSPs. Under transport in columns, WSP adsorption exhibited fast and slow kinetic adsorption regimes with time scales of minutes to hours. Slow adsorption kinetics in soil may lead to enhanced transport but also shorter lifetimes of biodegradable WSPs, assuming more rapid biodegradation when dissolved than adsorbed. This work establishes a basis for understanding the coupled adsorption and biodegradation dynamics of biodegradable WSPs in agricultural soils.


Asunto(s)
Dextranos , Suelo , Suelo/química , Estructura Molecular , Adsorción , Arena , Agua , Minerales
7.
J Pediatr Gastroenterol Nutr ; 79(2): 382-393, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38873914

RESUMEN

OBJECTIVES: Data regarding the occurrence of complications specifically during pediatric anesthesia for endoscopic procedures is limited. By evaluating such data, factors could be identified to assure proper staffing and preparation to minimize adverse events and improve patient safety during flexible endoscopy. METHODS: This retrospective cohort study included children undergoing anesthesia for gastroscopy, colonoscopy, bronchoscopy, or combined endoscopic procedures over 10-year period. The primary study aim was to evaluate the incidence of complications and identify risk factors for adverse events. RESULTS: Overall, 2064 endoscopic procedures including 1356 gastroscopies (65.7%), 93 colonoscopies (4.5%), 235 bronchoscopies (11.4%), and 380 combined procedures (18.4%) were performed. Of the 1613 patients, 151 (7.3%) patients exhibited an adverse event, with respiratory complications being the most common (65 [3.1%]). Combination of gastrointestinal endoscopies did not lead to an increased adverse event rate (gastroscopy: 5.5%, colonoscopy: 3.2%). Diagnostic endoscopy as compared to interventional had a lower rate. If bronchoscopy was performed, the rate was similar to that of bronchoscopy alone (19.5% vs. 20.4%). Age < 5.8 years or body weight less than 20 kg, bronchoscopy, American Society of Anesthesiologists status ≥ 2 or pre-existing anesthesia-relevant diseases, and urgency of the procedure were independent risk factors for adverse events. For each risk factor, the risk for events increased 2.1-fold [1.8-2.4]. CONCLUSIONS: This study identifies multiple factors that increase the rate of adverse events associated anesthesia-based endoscopy. Combined gastrointestinal procedures did not increase the risk for adverse events while combination of bronchoscopy to gastrointestinal endoscopy showed a similar risk as bronchoscopy alone.


Asunto(s)
Broncoscopía , Colonoscopía , Humanos , Estudios Retrospectivos , Factores de Riesgo , Niño , Femenino , Masculino , Preescolar , Lactante , Broncoscopía/efectos adversos , Broncoscopía/métodos , Adolescente , Colonoscopía/efectos adversos , Colonoscopía/métodos , Colonoscopía/estadística & datos numéricos , Incidencia , Anestesia/efectos adversos , Anestesia/métodos , Gastroscopía/efectos adversos , Gastroscopía/métodos , Endoscopía Gastrointestinal/efectos adversos , Endoscopía Gastrointestinal/métodos , Endoscopía Gastrointestinal/estadística & datos numéricos
8.
Br J Anaesth ; 133(2): 277-287, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38797635

RESUMEN

BACKGROUND: It is unclear whether optimising intraoperative cardiac index can reduce postoperative complications. We tested the hypothesis that maintaining optimised postinduction cardiac index during and for the first 8 h after surgery reduces the incidence of a composite outcome of complications within 28 days after surgery compared with routine care in high-risk patients having elective major open abdominal surgery. METHODS: In three German and two Spanish centres, high-risk patients having elective major open abdominal surgery were randomised to cardiac index-guided therapy to maintain optimised postinduction cardiac index (cardiac index at which pulse pressure variation was <12%) during and for the first 8 h after surgery using intravenous fluids and dobutamine or to routine care. The primary outcome was the incidence of a composite outcome of moderate or severe complications within 28 days after surgery. RESULTS: We analysed 318 of 380 enrolled subjects. The composite primary outcome occurred in 84 of 152 subjects (55%) assigned to cardiac index-guided therapy and in 77 of 166 subjects (46%) assigned to routine care (odds ratio: 1.87, 95% confidence interval: 1.03-3.39, P=0.038). Per-protocol analyses confirmed the results of the primary outcome analysis. CONCLUSIONS: Maintaining optimised postinduction cardiac index during and for the first 8 h after surgery did not reduce, and possibly increased, the incidence of a composite outcome of complications within 28 days after surgery compared with routine care in high-risk patients having elective major open abdominal surgery. Clinicians should not strive to maintain optimised postinduction cardiac index during and after surgery in expectation of reducing complications. CLINICAL TRIAL REGISTRATION: NCT03021525.


Asunto(s)
Abdomen , Complicaciones Posoperatorias , Humanos , Masculino , Femenino , Anciano , Persona de Mediana Edad , Complicaciones Posoperatorias/prevención & control , Complicaciones Posoperatorias/epidemiología , Abdomen/cirugía , Gasto Cardíaco , Dobutamina/administración & dosificación , Fluidoterapia/métodos , Anciano de 80 o más Años , Monitoreo Intraoperatorio/métodos , Cardiotónicos/uso terapéutico , Cardiotónicos/administración & dosificación , Procedimientos Quirúrgicos Electivos/efectos adversos
9.
Thorac Cardiovasc Surg ; 72(1): 2-10, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-36893800

RESUMEN

BACKGROUND: The German guideline on intensive care treatment of cardiac surgical patients provides evidence-based recommendations on management and monitoring. It remains unclear if, respectively, to which degree the guidelines are implemented into the daily practice. Therefore, this study aims to characterize the implementation of guideline recommendations in German cardiac surgical intensive care units (ICUs). METHODS: An internet-based online survey (42 questions, 9 topics) was sent to 158 German head physicians of cardiac surgical ICUs. To compare the effect over time, most questions were based on a previously performed survey (2013) after introduction of the last guideline update in 2008. RESULTS: A total of n = 65 (41.1%) questionnaires were included. Monitoring changed to increased provision of available transesophageal echocardiography specialists in 86% (2013: 72.6%), SvO2 measurement in 93.8% (2013: 55.1%), and electroencephalography in 58.5% (2013: 2.6%). The use of hydroxyethyl starch declined (9.4% vs. 2013: 38.7%), gelatin 4% presented the most administered colloid with 23.4% (2013: 17.4%). Low cardiac output syndrome was primarily treated with levosimendan (30.8%) and epinephrine (23.1%), while norepinephrine (44.6%) and dobutamine (16.9%) represented the most favored drug combination. The main way of distribution was web-based (50.9%), with increasing impact on therapy regimens (36.9% vs. 2013: 24%). CONCLUSION: Changes were found in all questioned sectors compared with the preceding survey, with persisting variability between ICUs. Recommendations of the updated guideline have increasingly entered clinical practice, with participants valuing the updated publication as clinically relevant.


Asunto(s)
Procedimientos Quirúrgicos Cardíacos , Humanos , Resultado del Tratamiento , Encuestas y Cuestionarios , Procedimientos Quirúrgicos Cardíacos/efectos adversos , Dobutamina/uso terapéutico , Cuidados Críticos , Alemania
10.
BMC Anesthesiol ; 24(1): 113, 2024 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-38521898

RESUMEN

BACKGROUND: Chronic heart failure (HF) is a common clinical condition associated with adverse outcomes in elderly patients undergoing non-cardiac surgery. This study aimed to estimate a clinically applicable NT-proBNP cut-off that predicts postoperative 30-day morbidity in a non-cardiac surgical cohort. METHODS: One hundred ninety-nine consecutive patients older than 65 years undergoing elective non-cardiac surgery with intermediate or high surgical risk were analysed. Preoperative NT-proBNP was measured, and clinical events were assessed up to postoperative day 30. The primary endpoint was the composite morbidity endpoint (CME) consisting of rehospitalisation, acute decompensated heart failure (ADHF), acute kidney injury (AKI), and infection at postoperative day 30. Secondary endpoints included perioperative fluid balance and incidence, duration, and severity of perioperative hypotension. RESULTS: NT-proBNP of 443 pg/ml had the highest accuracy in predicting the composite endpoint; a clinical cut-off of 450 pg/ml was implemented to compare clinical endpoints. Although 35.2% of patients had NT-proBNP above the threshold, only 10.6% had a known history of HF. The primary endpoint was the composite morbidity endpoint (CME) consisting of rehospitalisation, acute decompensated heart failure (ADHF), acute kidney injury (AKI), and infection. Event rates were significantly increased in patients with NT-proBNP > 450 pg/ml (70.7% vs. 32.4%, p < 0.001), which was due to the incidence of cardiac rehospitalisation (4.4% vs. 0%, p = 0.018), ADHF (20.1% vs. 4.0%, p < 0.001), AKI (39.8% vs. 8.3%, p < 0.001), and infection (46.3% vs. 24.4%, p < 0.01). Perioperative fluid balance and perioperative hypotension were comparable between groups. Preoperative NT-proBNP > 450 pg/ml was an independent predictor of the CME in a multivariable Cox regression model (hazard ratio 2.92 [1.72-4.94]). CONCLUSIONS: Patients with NT-proBNP > 450 pg/ml exhibited profoundly increased postoperative morbidity. Further studies should focus on interdisciplinary approaches to improve outcomes through integrated interventions in the perioperative period. TRIAL REGISTRATION: German Clinical Trials Register: DRKS00027871, 17/01/2022.


Asunto(s)
Lesión Renal Aguda , Insuficiencia Cardíaca , Hipotensión , Humanos , Anciano , Biomarcadores , Insuficiencia Cardíaca/epidemiología , Péptido Natriurético Encefálico , Fragmentos de Péptidos , Morbilidad , Lesión Renal Aguda/diagnóstico , Lesión Renal Aguda/epidemiología , Pronóstico
11.
J Wound Care ; 33(Sup5): S14-S21, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38683817

RESUMEN

OBJECTIVE: Family physicians (FPs) in Canada routinely perform in-office cutaneous surgery. There is strong evidence to support a moist wound healing environment, resulting in faster healing times and improved cosmesis. However, the wound care practices of FPs have not been previously studied. We aimed to examine the postoperative wound care practices of FPs after in-office cutaneous surgery. METHOD: An online survey was distributed to Canadian FPs to determine post-surgical wound care practices. The survey examined moist versus dry wound healing and the reasons for these recommendations were explored. Additional wound care practices were also studied. Appropriate statistical analyses were undertaken. RESULTS: A total of 573 (91.5%) FPs completed the survey. Just under half (49.2%) of FPs recommended moist wound healing to their patients, while the remaining respondents (50.8%) recommended dry wound healing. The most endorsed reason for both moist and dry wound care recommendations was prior training (63.1% and 65.3%, respectively). Most physicians (57.2%) recommended the use of a cream or ointment postoperatively. While there appeared to be consensus on recommending sun avoidance after cutaneous surgery (77.7%), additional wound care practices varied, including: the use of dressings; cleansing practices; smoking cessation; reduction in physical activity; photoprotection; water exposure; and scar treatment/cosmetic use. CONCLUSION: Almost half of FPs in Canada responding to the survey did not recommend moist wound healing despite strong evidence to support this practice. We also noted a diverse range of postoperative wound care practices after in-office cutaneous surgery. Therefore, these results highlight a critical need for consistent wound care recommendations following cutaneous surgery for FPs in Canada.


Asunto(s)
Pautas de la Práctica en Medicina , Cicatrización de Heridas , Humanos , Canadá , Masculino , Femenino , Pautas de la Práctica en Medicina/estadística & datos numéricos , Encuestas y Cuestionarios , Persona de Mediana Edad , Procedimientos Quirúrgicos Dermatologicos , Adulto , Cuidados Posoperatorios , Médicos de Familia , Procedimientos Quirúrgicos Ambulatorios
12.
J Clin Monit Comput ; 38(5): 945-959, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38381359

RESUMEN

Haemodynamic monitoring and management are cornerstones of perioperative care. The goal of haemodynamic management is to maintain organ function by ensuring adequate perfusion pressure, blood flow, and oxygen delivery. We here present guidelines on "Intraoperative haemodynamic monitoring and management of adults having non-cardiac surgery" that were prepared by 18 experts on behalf of the German Society of Anaesthesiology and Intensive Care Medicine (Deutsche Gesellschaft für Anästhesiologie und lntensivmedizin; DGAI).


Asunto(s)
Anestesiología , Cuidados Críticos , Monitorización Hemodinámica , Hemodinámica , Monitoreo Intraoperatorio , Sociedades Médicas , Adulto , Humanos , Anestesiología/métodos , Anestesiología/normas , Cuidados Críticos/métodos , Cuidados Críticos/normas , Alemania , Monitorización Hemodinámica/métodos , Monitoreo Intraoperatorio/métodos , Monitoreo Intraoperatorio/normas , Atención Perioperativa/métodos , Atención Perioperativa/normas , Sociedades Científicas , Procedimientos Quirúrgicos Operativos , Literatura de Revisión como Asunto
13.
Int J Mol Sci ; 25(13)2024 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-39000529

RESUMEN

Despite significant efforts toward improving therapy for septic shock, mortality remains high. Applying veno-arterial (V-A) extracorporeal membrane oxygenation (ECMO) in this context remains controversial. Since the cannulation of the femoral artery for V-A ECMO return leads to lower body hyperoxia, this study investigated the impact of V-A ECMO therapy on the intestinal and hepatic microcirculation during septic shock in a rodent model. Thirty male Lewis rats were randomly assigned to receive V-A ECMO therapy with low (60 mL/kg/min) or high (90 mL/kg/min) blood flow or a sham procedure. Hemodynamic data were collected through a pressure-volume catheter in the left ventricle and a catheter in the lateral tail artery. Septic shock was induced by intravenous administration of lipopolysaccharide (1 mg/kg). The rats received lung-protective ventilation during V-A ECMO therapy. The hepatic and intestinal microcirculation was measured by micro-lightguide spectrophotometry after median laparotomy for two hours. Systemic and pulmonary inflammation was detected via enzyme-linked immunosorbent assays (ELISA) of the plasma and bronchoalveolar lavage (BAL), respectively, measuring tumor necrosis factor-alpha (TNF-α), interleukins 6 (IL-6) and 10 (IL-10), and C-X-C motif ligands 2 (CXCL2) and 5 (CXCL5). Oxygen saturation and relative hemoglobin concentration were reduced in the hepatic and intestinal microcirculation during V-A ECMO therapy, independent of the blood flow rate. Further, rats treated with V-A ECMO therapy also presented elevated systolic, diastolic, and mean arterial blood pressure and increased stroke volume, cardiac output, and left ventricular end-diastolic volume. However, left ventricular end-diastolic pressure was only elevated during high-flow V-A ECMO therapy. Blood gas analysis revealed a dilutional anemia during V-A ECMO therapy. ELISA analysis showed an elevated plasma CXCL2 concentration only during high-flow V-A ECMO therapy and elevated BAL CXCL2 and CXCL5 concentrations only during low-flow V-A ECMO therapy. Rats undergoing V-A ECMO therapy exhibited impaired microcirculation of the intestine and liver during septic shock despite increased blood pressure and cardiac output. Increased pulmonary inflammation was detected only during low-flow V-A ECMO therapy in septic shock.


Asunto(s)
Modelos Animales de Enfermedad , Oxigenación por Membrana Extracorpórea , Intestinos , Hígado , Microcirculación , Ratas Endogámicas Lew , Choque Séptico , Animales , Oxigenación por Membrana Extracorpórea/métodos , Masculino , Ratas , Choque Séptico/terapia , Choque Séptico/fisiopatología , Choque Séptico/metabolismo , Hígado/metabolismo , Hígado/irrigación sanguínea , Intestinos/irrigación sanguínea , Neumonía/terapia , Neumonía/metabolismo , Neumonía/fisiopatología , Hemodinámica , Factor de Necrosis Tumoral alfa/metabolismo , Factor de Necrosis Tumoral alfa/sangre
14.
Int J Mol Sci ; 25(12)2024 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-38928327

RESUMEN

Treatment of critically ill patients with venovenous (V-V) extracorporeal membrane oxygenation (ECMO) has gained wide acceptance in the last few decades. However, the use of V-V ECMO in septic shock remains controversial. The effect of ECMO-induced inflammation on the microcirculation of the intestine, liver, and critically damaged lungs is unknown. Therefore, the aim of this study was to measure the hepatic and intestinal microcirculation and pulmonary inflammatory response in a model of V-V ECMO and septic shock in the rat. Twenty male Lewis rats were randomly assigned to receive V-V ECMO therapy or a sham procedure. Hemodynamic data were measured by a pressure-volume catheter in the left ventricle and a catheter in the lateral tail artery. Septic shock was induced by the intravenous infusion of lipopolysaccharide (1 mg/kg). During V-V ECMO therapy, rats received lung-protective ventilation. The hepatic and intestinal microcirculation was assessed by micro-lightguide spectrophotometry after median laparotomy for 2 h. Systemic and pulmonary inflammation was measured by enzyme-linked immunosorbent assays of plasma and bronchoalveolar lavage (BAL), respectively, which included tumor necrosis factor alpha (TNF-α), interleukin 6 (IL-6), IL-10, C-X-C motif ligand 2 (CXCL2), and CXCL5. Reduced oxygen saturation and relative hemoglobin concentration were measured in the hepatic and intestinal microcirculation during treatment with V-V ECMO. These animals also showed increased systolic, mean, and diastolic blood pressures. While no differences in left ventricular ejection fraction were observed, animals in the V-V ECMO group presented an increased heart rate, stroke volume, and cardiac output. Blood gas analysis showed dilutional anemia during V-V ECMO, whereas plasma analysis revealed a decreased concentration of IL-10 during V-V ECMO therapy, and BAL measurements showed increased concentrations of TNF-α, CXCL2, and CXCL5. Rats treated with V-V ECMO showed impaired microcirculation of the intestine and liver during septic shock despite increased blood pressure and cardiac output. Despite lung-protective ventilation, increased pulmonary inflammation was recognized during V-V ECMO therapy in septic shock.


Asunto(s)
Modelos Animales de Enfermedad , Oxigenación por Membrana Extracorpórea , Intestinos , Hígado , Microcirculación , Ratas Endogámicas Lew , Choque Séptico , Animales , Oxigenación por Membrana Extracorpórea/métodos , Masculino , Ratas , Choque Séptico/terapia , Choque Séptico/fisiopatología , Choque Séptico/metabolismo , Intestinos/irrigación sanguínea , Hígado/metabolismo , Hígado/irrigación sanguínea , Neumonía/terapia , Neumonía/metabolismo , Neumonía/fisiopatología , Hemodinámica , Factor de Necrosis Tumoral alfa/metabolismo , Factor de Necrosis Tumoral alfa/sangre
15.
Int J Mol Sci ; 25(4)2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38397016

RESUMEN

The effect of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on the coagulation system is not fully understood. SARS-CoV-2 penetrates cells through angiotensin-converting enzyme 2 (ACE2) receptors, leading to its downregulation. Des-arginine9-bradykinin (DA9B) is degraded by ACE2 and causes vasodilation and increased vascular permeability. Furthermore, DA9B is associated with impaired platelet function. Therefore, the aim of this study was to evaluate the effects of DA9B on platelet function and coagulopathy in critically ill coronavirus disease 2019 (COVID-19) patients. In total, 29 polymerase-positive SARS-CoV-2 patients admitted to the intensive care unit of the University Hospital of Giessen and 29 healthy controls were included. Blood samples were taken, and platelet impedance aggregometry and rotational thromboelastometry were performed. Enzyme-linked immunosorbent assays measured the concentrations of DA9B, bradykinin, and angiotensin 2. Significantly increased concentrations of DA9B and angiotensin 2 were found in the COVID-19 patients. A negative effect of DA9B on platelet function and intrinsic coagulation was also found. A sub-analysis of moderate and severe acute respiratory distress syndrome patients revealed a negative association between DA9B and platelet counts and fibrinogen levels. DA9B provokes inhibitory effects on the intrinsic coagulation system in COVID-19 patients. This negative feedback seems reasonable as bradykinin, which is transformed to DA9B, is released after contact activation. Nevertheless, further studies are needed to confirm our findings.


Asunto(s)
COVID-19 , Humanos , SARS-CoV-2/metabolismo , Bradiquinina/farmacología , Bradiquinina/metabolismo , Enzima Convertidora de Angiotensina 2 , Enfermedad Crítica , Angiotensinas
16.
Oncologist ; 28(9): 812-822, 2023 09 07.
Artículo en Inglés | MEDLINE | ID: mdl-37011230

RESUMEN

BACKGROUND: Risk stratification tools for patients with advanced melanoma (AM) treated with immune checkpoint inhibitors (ICI) are lacking. We identified a new prognostic model associated with overall survival (OS). PATIENTS AND METHODS: A total of 318 treatment naïve patients with AM receiving ICI were collected from a multi-centre retrospective cohort study. LASSO Cox regression identified independent prognostic factors associated with OS. Model validation was carried out on 500 iterations of bootstrapped samples. Harrel's C-index was calculated and internally validated to outline the model's discriminatory performance. External validation was carried out in 142 advanced melanoma patients receiving ICI in later lines. RESULTS: High white blood cell count (WBC), high lactate dehydrogenase (LDH), low albumin, Eastern Cooperative Oncology Group (ECOG) performance status ≥1, and the presence of liver metastases were included in the model. Patients were parsed into 3 risk groups: favorable (0-1 factors) OS of 52.9 months, intermediate (2-3 factors) OS 13.0 months, and poor (≥4 factors) OS 2.7 months. The C-index of the model from the discovery cohort was 0.69. External validation in later-lines (N = 142) of therapy demonstrated a c-index of 0.65. CONCLUSIONS: Liver metastases, low albumin, high LDH, high WBC, and ECOG≥1 can be combined into a prognostic model for AM patients treated with ICI.


Asunto(s)
Neoplasias Hepáticas , Melanoma , Humanos , Pronóstico , Inhibidores de Puntos de Control Inmunológico/farmacología , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Estudios Retrospectivos , Melanoma/patología , Albúminas
17.
Acc Chem Res ; 55(16): 2163-2167, 2022 08 16.
Artículo en Inglés | MEDLINE | ID: mdl-35929823

RESUMEN

Water-soluble polymers (WSPs) have unique properties that are valuable in diverse applications ranging from home and personal care products to agricultural formulations. For applications that result in the release of WSPs into natural environments or engineered systems, such as agricultural soils and wastewater streams, biodegradable as opposed to nonbiodegradable WSPs have the advantage of breaking down and, thereby, eliminating the risk of persistence and accumulation. In this Commentary, we emphasize central steps in WSP biodegradation, discuss how these steps depend on both WSP properties and characteristics of the receiving environment, and highlight critical requirements for testing WSP biodegradability.


Asunto(s)
Polímeros , Agua , Biodegradación Ambiental , Aguas Residuales
18.
BMC Health Serv Res ; 23(1): 1392, 2023 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-38082272

RESUMEN

BACKGROUND: Health care has the intrinsic obligation to preserve health. This concept is also applicable to planetary health. Nitrous oxide (N2O) lacks clinical indications in modern anaesthesia, while it is a high-potential greenhouse gas. Its seemingly low cost contrasts with the consequential externalised socio-economic costs due to its contribution to the climate crisis, which is approximately €698 per emitted ton of CO2 equivalent. This difference can be internalised through emission taxation. In this study, we aim to evaluate how much N2O - total amount and converted to CO2 equivalent - is used at a German university hospital and compare this amount to that used at European hospitals. Furthermore, how the cost of N2O usage changes under different emission taxation scenarios is calculated. METHODS: This trial was a retrospective observational study at a German university hospital with approximately 1,250 beds between 2016 and 2020. Additionally, five European hospitals from the Health Care Without Harm Network were used for comparison from a European perspective. The main outcome parameters were the amount of N2O used, in total and converted to CO2 equivalent, and the total cost at emission taxation of €0, €25, €55 and €698 per ton CO2 equivalent. RESULTS: At the peak, 2,104 tCO2 equivalent in N2O was emitted in 2019. The actual cost was €14,040 in this year, while the corresponding socio-economic damage due to the climate crisis was almost €1.5 million. Other European hospitals showed comparable amounts of emissions. CONCLUSIONS: The annual peak amount of emitted N2O corresponded to the total annual greenhouse gas emission of 188 people in Germany. To achieve a drastic reduction in use, the abandonment of recommendations by anaesthesiologic societies appears necessary, in addition to an internalisation of future costs via emission taxation, which will cause inadequate cost for a medication without relevant benefit or indication. To that end, the inclusion of health sector emissions within national or international greenhouse gas taxation, for example, the European Union Emissions Trading System, appears necessary and expedient in view of the urgent need to address the ecological transformation. TRIAL REGISTRATION: The trial was registered with the German Clinical Trials Register, identifier DRKS00024973 on 12/04/2021.


Asunto(s)
Anestesia , Gases de Efecto Invernadero , Humanos , Gases de Efecto Invernadero/análisis , Óxido Nitroso/análisis , Dióxido de Carbono/análisis , Análisis Costo-Beneficio , Hospitales , Impuestos
19.
Neurocrit Care ; 2023 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-37697129

RESUMEN

BACKGROUND: The objective of this study was to analyze the impact of a structured educational intervention on the implementation of guideline-recommended pain, agitation, and delirium (PAD) assessment. METHODS: This was a prospective, multinational, interventional before-after trial conducted at 12 intensive care units from 10 centers in Germany, Austria, Switzerland, and the UK. Intensive care units underwent a 6-week structured educational program, comprising online lectures, instructional videos, educational handouts, and bedside teaching. Patient-level PAD assessment data were collected in three 1-day point-prevalence assessments before (T1), 6 weeks after (T2), and 1 year after (T3) the educational program. RESULTS: A total of 430 patients were included. The rate of patients who received all three PAD assessments changed from 55% (107/195) at T1 to 53% (68/129) at T2, but increased to 73% (77/106) at T3 (p = 0.003). The delirium screening rate increased from 64% (124/195) at T1 to 65% (84/129) at T2 and 77% (82/106) at T3 (p = 0.041). The pain assessment rate increased from 87% (170/195) at T1 to 92% (119/129) at T2 and 98% (104/106) at T3 (p = 0.005). The rate of sedation assessment showed no signficiant change. The proportion of patients who received nonpharmacological delirium prevention measures increased from 58% (114/195) at T1 to 80% (103/129) at T2 and 91% (96/106) at T3 (p < 0.001). Multivariable regression revealed that at T3, patients were more likely to receive a delirium assessment (odds ratio [OR] 2.138, 95% confidence interval [CI] 1.206-3.790; p = 0.009), sedation assessment (OR 4.131, 95% CI 1.372-12.438; p = 0.012), or all three PAD assessments (OR 2.295, 95% CI 1.349-3.903; p = 0.002) compared with T1. CONCLUSIONS: In routine care, many patients were not assessed for PAD. Assessment rates increased significantly 1 year after the intervention. Clinical trial registration ClinicalTrials.gov: NCT03553719.

20.
Chimia (Aarau) ; 77(11): 764-772, 2023 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-38047844

RESUMEN

Agricultural formulations contain water-soluble and water-dispersible polymers (WSPs and WDPs) to increase the application efficiency of the active ingredients (e.g. pesticides and fertilizers). Despite their direct release to soils and crops, there is currently no inventory of used polymers and their fate in soils is poorly studied and understood. Herein, we identify WSPs and WDPs used in agricultural formulations on the German and Swiss markets. By searching the scientific literature, patents, and manufacturer websites, we tentatively identified that 233 of the 1815 listed trade names of formulation additives contained polymers, the majority of which belonged to three main chemical classes: polyethylene glycol (PEG)-based (co)polymers, functionalized polysaccharides (PSacs), and vinylic (co)polymers (VCPs). We report information on their functionalization, molecular weights, and market significance. In 2015, their estimated combined annual application volume in Switzerland surpassed 100 tonnes. Low molecular weight PEGs and natural, unfunctionalized PSacs reportedly biodegrade, suggesting no accumulation in soils associated with their use as formulation additives. Conversely, high molecular weight functionalized PEGs, functionalized PSacs, and the majority of the VCPs have been reported to undergo only slow or no soil biodegradation. These polymers may thus persist and accumulate in agricultural soils, requiring more detailed investigations of their environmental fate and resulting exposure scenarios. There is a need for systematic studies on the effects of polymer structure, molecular weight, and functionalization on soil biodegradability.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA