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1.
Front Bioeng Biotechnol ; 12: 1363538, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38646013

RESUMO

Introduction: Recent advances have enabled organotypic culture of beating human myocardial slices that are stable for weeks. However, human myocardial samples are rare, exhibit high variability and frequently originate from diseased hearts. Thus, there is a need to adapt long-term slice culture for animal myocardium. When applied to animal cardiac slices, studies in healthy or genetically modified myocardium will be possible. We present the culture of slices from rabbit hearts, which resemble the human heart in microstructure, electrophysiology and excitation-contraction coupling. Methods: Left ventricular myocardium from New Zealand White rabbits was cut using a vibratome and cultured in biomimetic chambers for up to 7 days (d). Electro-mechanical uncoupling agents 2,3-butanedione monoxime (BDM) and cytochalasin D (CytoD) were added during initiation of culture and effects on myocyte survival were quantified. We investigated pacing rates (0.5 Hz, 1 Hz, and 2 Hz) and hormonal supplements (cortisol, T3, catecholamines) at physiological plasma concentrations. T3 was buffered using BSA. Contractile force was recorded continuously. Glucose consumption and lactate production were measured. Whole-slice Ca2+ transients and action potentials were recorded. Effects of culture on microstructure were investigated with confocal microscopy and image analysis. Results: Protocols for human myocardial culture resulted in sustained contracture and myocyte death in rabbit slices within 24 h, which could be prevented by transient application of a combination of BDM and CytoD. Cortisol stabilized contraction amplitude and kinetics in culture. T3 and catecholaminergic stimulation did not further improve stability. T3 and higher pacing rates increased metabolic rate and lactate production. T3 stabilized the response to ß-adrenergic stimulation over 7 d. Pacing rates above 1 Hz resulted in progredient decline in contraction force. Image analysis revealed no changes in volume fractions of cardiomyocytes or measures of fibrosis over 7 d. Ca2+ transient amplitudes and responsiveness to isoprenaline were comparable after 1 d and 7 d, while Ca2+ transient duration was prolonged after 7 d in culture. Conclusions: A workflow for rabbit myocardial culture has been established, preserving function for up to 7 d. This research underscores the importance of glucocorticoid signaling in maintaining tissue function and extending culture duration. Furthermore, BDM and CytoD appear to protect from tissue damage during the initiation phase of tissue culture.

2.
J Huntingtons Dis ; 12(3): 267-281, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37694372

RESUMO

BACKGROUND: To date, it is still controversial whether tau phosphorylation plays a role in Huntington's disease (HD), as previous studies demonstrated either no alterations or increases in phosphorylated tau (pTau) in HD postmortem brain and mouse models. OBJECTIVE: The goal of this study was to determine whether total tau and pTau levels are altered in HD. METHODS: Immunohistochemistry, cellular fractionations, and western blots were used to measure total tau and pTau levels in a large cohort of HD and control postmortem prefrontal cortex (PFC). Furthermore, western blots were performed to assess tau, and pTau levels in HD and control isogenic embryonic stem cell (ESC)-derived cortical neurons and neuronal stem cells (NSCs). Similarly, western blots were used to assess tau and pTau levels in HttQ111 and transgenic R6/2 mice. Lastly, total tau levels were assessed in HD and healthy control plasma using Quanterix Simoa assay. RESULTS: Our results revealed that, while there was no difference in total tau or pTau levels in HD PFC compared to controls, the levels of tau phosphorylated at S396 were increased in PFC samples from HD patients 60 years or older at time of death. Additionally, tau and pTau levels were not changed in HD ESC-derived cortical neurons and NSCs. Similarly, total tau or pTau levels were not altered in HttQ111 and transgenic R6/2 mice compared to wild-type littermates. Lastly, tau levels were not changed in plasma from a small cohort of HD patients compared to controls. CONCLUSIONS: Together these findings demonstrate that pTau-S396 levels increase significantly with age in HD PFC.


Assuntos
Doença de Huntington , Camundongos , Animais , Humanos , Doença de Huntington/metabolismo , Fosforilação , Serina/metabolismo , Camundongos Transgênicos , Córtex Pré-Frontal/metabolismo , Modelos Animais de Doenças
3.
mBio ; 14(5): e0070623, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37607061

RESUMO

IMPORTANCE: All enveloped viruses enter cells by fusing their envelope with a target cell membrane while avoiding premature fusion with membranes of the producer cell-the latter being particularly important for viruses that bud at internal membranes. Flaviviruses bud in the endoplasmic reticulum, are transported through the TGN to reach the external milieu, and enter other cells via receptor-mediated endocytosis. The trigger for membrane fusion is the acidic environment of early endosomes, which has a similar pH to the TGN of the producer cell. The viral particles therefore become activated to react to mildly acidic pH only after their release into the neutral pH extracellular environment. Our study shows that for yellow fever virus (YFV), the mechanism of activation involves actively knocking out the fusion brake (protein pr) through a localized conformational change of the envelope protein upon exposure to the neutral pH external environment. Our study has important implications for understanding the molecular mechanism of flavivirus fusion activation in general and points to an alternative way of interfering with this process as an antiviral treatment.


Assuntos
Flavivirus , Febre Amarela , Humanos , Flavivirus/genética , Proteínas do Envelope Viral/metabolismo , Vírus da Febre Amarela/genética , Membrana Celular/metabolismo
4.
medRxiv ; 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37333415

RESUMO

Background: To date, it is still controversial whether tau phosphorylation plays a role in Huntington's disease (HD), as previous studies demonstrated either no alterations or increases in phosphorylated tau (pTau) in HD post-mortem brain and mouse models. Objectives: The goal of this study was to determine whether total tau and pTau levels are altered in HD. Methods: Immunohistochemistry, cellular fractionations, and western blots were used to measure tau and pTau levels in a large cohort of HD and control post-mortem prefrontal cortex (PFC). Furthermore, western blots were performed to assess tau, and pTau levels in HD and control isogenic embryonic stem cell (ESC)-derived cortical neurons and neuronal stem cells (NSCs). Similarly, western blots were used to assess tau and pTau in Htt Q111 and transgenic R6/2 mice. Lastly, total tau levels were assessed in HD and healthy control plasma using Quanterix Simoa assay. Results: Our results revealed that, while there was no difference in tau or pTau levels in HD PFC compared to controls, tau phosphorylated at S396 levels were increased in PFC samples from HD patients 60 years or older at time of death. Additionally, tau and pTau levels were not changed in HD ESC-derived cortical neurons and NSCs. Similarly, tau or pTau levels were not altered in Htt Q111 and transgenic R6/2 mice compared to wild-type littermates. Lastly, tau levels were not changed in plasma from a small cohort of HD patients compared to controls. Conclusion: Together these findings demonstrate that pTau-S396 levels increase significantly with age in HD PFC.

5.
Radiat Res ; 199(6): 571-582, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37057983

RESUMO

The goal of the RENEB inter-laboratory comparison 2021 exercise was to simulate a large-scale radiation accident involving a network of biodosimetry labs. Labs were required to perform their analyses using different biodosimetric assays in triage mode scoring and to rapidly report estimated radiation doses to the organizing institution. This article reports the results obtained with the cytokinesis-block micronucleus assay. Three test samples were exposed to blinded doses of 0, 1.2 and 3.5 Gy X-ray doses (240 kVp, 13 mA, ∼75 keV, 1 Gy/min). These doses belong to 3 triage categories of clinical relevance: a low dose category, for no exposure or exposures inferior to 1 Gy, requiring no direct treatment of subjects; a medium dose category, with doses ranging from 1 to 2 Gy, and a high dose category, after exposure to doses higher than 2 Gy, with the two latter requiring increasing medical attention. After irradiation the test samples (no. 1, no. 2 and no. 3) were sent by the organizing laboratory to 14 centers participating in the micronucleus assay exercise. Laboratories were asked to setup micronucleus cultures and to perform the micronucleus assay in triage mode, scoring 500 binucleated cells manually, or 1,000 binucleated cells in automated/semi-automated mode. One laboratory received no blood samples, but scored pictures from another lab. Based on their calibration curves, laboratories had to provide estimates of the administered doses. The accuracy of the reported dose estimates was further analyzed by the micronucleus assay lead. The micronucleus assay allowed classification of samples in the corresponding clinical triage categories (low, medium, high dose category) in 88% of cases (manual scoring, 88%; semi-automated scoring, 100%; automated scoring, 73%). Agreement between scoring laboratories, assessed by calculating the Fleiss' kappa, was excellent (100%) for semi-automated scoring, good (83%) for manual scoring and poor (53%) for fully automated scoring. Correct classification into triage scoring dose intervals (reference dose ±0.5 Gy for doses ≤2.5 Gy, or reference dose ±1 Gy for doses >2.5 Gy), recommended for triage biodosimetry, was obtained in 79% of cases (manual scoring, 73%; semi-automated scoring, 100%; automated scoring, 67%). The percentage of dose estimates whose 95% confidence intervals included the reference dose was 58% (manual scoring, 48%; semiautomated scoring, 72%; automated scoring, 60%). For the irradiated samples no. 2 and no. 3, a systematic shift towards higher dose estimations was observed. This was also noticed with the other cytogenetic assays in this intercomparison exercise. Accuracy of the rapid triage modality could be maintained when the number of manually scored cells was scaled down to 200 binucleated cells. In conclusion, the micronucleus assay, preferably performed in a semi-automated or manual scoring mode, is a reliable technique to perform rapid biodosimetry analysis in large-scale radiation emergencies.


Assuntos
Citocinese , Liberação Nociva de Radioativos , Humanos , Relação Dose-Resposta à Radiação , Citocinese/efeitos da radiação , Testes para Micronúcleos/métodos , Bioensaio/métodos , Radiometria/métodos
6.
Radiat Res ; 199(6): 556-570, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37018160

RESUMO

After large-scale radiation accidents where many individuals are suspected to be exposed to ionizing radiation, biological and physical retrospective dosimetry assays are important tools to aid clinical decision making by categorizing individuals into unexposed/minimally, moderately or highly exposed groups. Quality-controlled inter-laboratory comparisons of simulated accident scenarios are regularly performed in the frame of the European legal association RENEB (Running the European Network of Biological and Physical retrospective Dosimetry) to optimize international networking and emergency readiness in case of large-scale radiation events. In total 33 laboratories from 22 countries around the world participated in the current RENEB inter-laboratory comparison 2021 for the dicentric chromosome assay. Blood was irradiated in vitro with X rays (240 kVp, 13 mA, ∼75 keV, 1 Gy/min) to simulate an acute, homogeneous whole-body exposure. Three blood samples (no. 1: 0 Gy, no. 2: 1.2 Gy, no. 3: 3.5 Gy) were sent to each participant and the task was to culture samples, to prepare slides and to assess radiation doses based on the observed dicentric yields from 50 manually or 150 semi-automatically scored metaphases (triage mode scoring). Approximately two-thirds of the participants applied calibration curves from irradiations with γ rays and about 1/3 from irradiations with X rays with varying energies. The categorization of the samples in clinically relevant groups corresponding to individuals that were unexposed/minimally (0-1 Gy), moderately (1-2 Gy) or highly exposed (>2 Gy) was successfully performed by all participants for sample no. 1 and no. 3 and by ≥74% for sample no. 2. However, while most participants estimated a dose of exactly 0 Gy for the sham-irradiated sample, the precise dose estimates of the samples irradiated with doses >0 Gy were systematically higher than the corresponding reference doses and showed a median deviation of 0.5 Gy (sample no. 2) and 0.95 Gy (sample no. 3) for manual scoring. By converting doses estimated based on γ-ray calibration curves to X-ray doses of a comparable mean photon energy as used in this exercise, the median deviation decreased to 0.27 Gy (sample no. 2) and 0.6 Gy (sample no. 3). The main aim of biological dosimetry in the case of a large-scale event is the categorization of individuals into clinically relevant groups, to aid clinical decision making. This task was successfully performed by all participants for the 0 Gy and 3.5 Gy samples and by 74% (manual scoring) and 80% (semiautomatic scoring) for the 1.2 Gy sample. Due to the accuracy of the dicentric chromosome assay and the high number of participating laboratories, a systematic shift of the dose estimates could be revealed. Differences in radiation quality (X ray vs. γ ray) between the test samples and the applied dose effect curves can partly explain the systematic shift. There might be several additional reasons for the observed bias (e.g., donor effects, transport, experimental conditions or the irradiation setup) and the analysis of these reasons provides great opportunities for future research. The participation of laboratories from countries around the world gave the opportunity to compare the results on an international level.


Assuntos
Aberrações Cromossômicas , Liberação Nociva de Radioativos , Humanos , Estudos Retrospectivos , Radiometria/métodos , Bioensaio/métodos , Cromossomos , Relação Dose-Resposta à Radiação
7.
Sci Rep ; 12(1): 6670, 2022 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-35461341

RESUMO

Unemployment is associated with a variety of adverse health-related outcomes, yet little data on primary care services for this risk group exist. Using data from two surveys, we analyzed the frequency of GP contacts and patients' experiences with GPs comparing unemployed with employed individuals. Data of the German Health Interview and Examination Survey for Adults (DEGS1), a nationwide cross-sectional study (n = 8151), were analyzed regarding associations between employment status and the number of GP visits. The General Practice Care-1 study (GPCare-1), a cross-sectional questionnaire survey (n = 813), evaluated patients' communication with their GP. Data were collected from June to August 2020 in 12 teaching practices affiliated with our university. The statistical analysis included individuals of working age (18-64 years old) (DEGS1 n = 5659, GPCare-1 n = 587). In both studies, working age subpopulations were analyzed (DEGS1: n = 5659 of 8151, GPCare-1: n = 587 of 813). In DEGS1, the prevalence of unemployment was 6.5% (n = 372). Unemployed individuals had more GP contacts in the last 12 months (4.50 vs. 2.86, p < 0.001). In the GPCare-1 study, unemployed individuals (6.6%, n = 39) were significantly less satisfied with GP communication: enough space in consultations (42.9% vs. 60.3%, p = 0.043), feeling comfortable to address sensitive topics (44.1% vs. 65.9%, p = 0.010), problems taken very seriously by GP (48.6% vs. 70.6%, p = 0.007). Yet, they were more willing to accept GPs' help for psychosocial burdens (67.6% vs. 47.6%, p = 0.024). GPs should be aware that patients with unemployment wish more support to cope with their burdening situation.


Assuntos
Medicina Geral , Desemprego , Adolescente , Adulto , Estudos Transversais , Humanos , Pessoa de Meia-Idade , Satisfação do Paciente , Encaminhamento e Consulta , Inquéritos e Questionários , Adulto Jovem
8.
Arch Gynecol Obstet ; 305(6): 1481-1490, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34954814

RESUMO

INTRODUCTION: Da-Vinci-Xi is the most recent device used in gynecologic robotic surgery. The aim of the present study was to compare the long-term satisfaction of patients who had undergone conventional laparoscopic hysterectomy or robotic assisted laparoscopic hysterectomy using the Da-Vinci-Xi surgical system. METHODS: All hysterectomies performed at the University Hospital of Luebeck from 2018 to 2019 were reviewed. Postoperative outcomes were compared between women who had undergone total hysterectomy with da Vinci Xi (n = 42) or conventional laparoscopy (n = 97). Postoperative outcomes included pain, elimination of complaints after surgery, bladder function, sexual function, satisfaction with the cosmetic outcome, positive experiences after robotic surgery, and satisfaction with the surgeon's preoperative explanation. Obese patients were evaluated separately in a subgroup analysis. RESULTS: Both groups had similar baseline characteristics and complication rates. Preoperative complaints subsided after surgery in a little more than 90% of patients. No significant differences were noted between groups in this regard (p = 0.262), or with reference to postoperative pain after one week (p = 0.866) and one month (p = 0.580), stress incontinence (p = 0.343), sexual function (p = 0.766) and the cosmetic outcome of the abdominal incisions (p = 0.273). The majority of patients who had undergone robotic surgery (96.8%) would be willing to undergo the procedure again if necessary. The subgroup analysis of obese patients revealed no significant differences. CONCLUSION: The Da-Vinci-Xi device did not improve the long-term surgical satisfaction of normal-weight or obese patients who underwent hysterectomy compared with patients who underwent conventional laparoscopy performed by experienced laparoscopic surgeons.


Assuntos
Laparoscopia , Procedimentos Cirúrgicos Robóticos , Feminino , Humanos , Histerectomia/efeitos adversos , Histerectomia/métodos , Laparoscopia/métodos , Obesidade/complicações , Obesidade/cirurgia , Satisfação do Paciente , Satisfação Pessoal , Estudos Retrospectivos , Procedimentos Cirúrgicos Robóticos/efeitos adversos , Procedimentos Cirúrgicos Robóticos/métodos , Resultado do Tratamento
9.
BMC Pregnancy Childbirth ; 21(1): 356, 2021 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-33947354

RESUMO

BACKGROUND: The American College of Obstetricians and Gynecologists (ACOG) introduced a new standard of care in 2014, extending the duration of the second stage of labor in order to reduce caesarean delivery (CD) rates and its severe complications. The aim of the present study is to evaluate success rates of trial of labor after caesarean section (TOLAC), as well as maternal and neonatal outcomes after the establishment of the recent guidelines. METHODS: A retrospective study was performed at two large departments in Germany from January 2008 to January 2018. Patients undergoing TOLAC were divided into two groups. Group I (958 patients) was constituted before the establishment of the current guidelines, and Group II (588 patients) after the establishment of the guidelines. A subgroup analysis was performed to compare neonatal outcomes after successful TOLAC and operative vaginal delivery with those after failed TOLAC and secondary CD. RESULTS: The success rate of vaginal births after cesarean section (VBAC) fell from 66.4% in Group I to 55.8% in Group II (p < 0.001). The median duration of the second stage of labor was statistically significantly longer in Group II than in Group I (79.3 ± 61.9 vs. 69.3 ± 58.2 min) for patients without previous vaginal birth. The incidence of operative vaginal delivery decreased from Group I to Group II (9.6% vs. 6.8%). The incidence of third- and fourth-degree perineal lacerations, blood loss and emergency CD were similar in the two groups. Concerning the neonatal outcome, our groups did not differ significantly in regard of rates of umbilical artery cord pH < 7.1 (p = 0.108), the 5-min Apgar scores below 7 (p = 0.224) and intubation (p = 0.547). However, the transfer rates to the neonatal care unit were significantly higher in Group II than in Group I (p < 0.001). Neonatal outcomes did not differ significantly in the subgroup analysis. CONCLUSION: Extending the second stage of labor does not necessarily result in more vaginal births after TOLAC. Maternal and neonatal outcomes were similar in both groups. Further studies will be needed to evaluate the role of operative vaginal delivery and the duration of the second stage of labor in TOLAC.


Assuntos
Segunda Fase do Trabalho de Parto , Prova de Trabalho de Parto , Nascimento Vaginal Após Cesárea , Adulto , Feminino , Humanos , Recém-Nascido , Gravidez , Resultado da Gravidez , Estudos Retrospectivos
10.
Cell Mol Life Sci ; 78(6): 2857-2876, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33074350

RESUMO

Cell therapies for autoimmune diseases using tolerogenic dendritic cells (tolDC) have been promisingly explored. A major stumbling block has been generating stable tolDC, with low risk of converting to mature immunogenic DC (mDC), exacerbating disease. mDC induction involves a metabolic shift to lactate production from oxidative phosphorylation (OXPHOS) and ß-oxidation, the homeostatic energy source for resting DC. Inhibition of glycolysis through the administration of 2-deoxy glucose (2-DG) has been shown to prevent autoimmune disease experimentally but is not clinically feasible. We show here that treatment of mouse bone marrow-derived tolDC ex vivo with low-dose 2-DG (2.5 mM) (2-DGtolDC) induces a stable tolerogenic phenotype demonstrated by their failure to engage lactate production when challenged with mycobacterial antigen (Mtb). ~ 15% of 2-DGtolDC express low levels of MHC class II and 30% express CD86, while they are negative for CD40. 2-DGtolDC also express increased immune checkpoint molecules PDL-1 and SIRP-1α. Antigen-specific T cell proliferation is reduced in response to 2-DGtolDC in vitro. Mtb-stimulated 2-DGtolDC do not engage aerobic glycolysis but respond to challenge via increased OXPHOS. They also have decreased levels of p65 phosphorylation, with increased phosphorylation of the non-canonical p100 pathway. A stable tolDC phenotype is associated with sustained SIRP-1α phosphorylation and p85-AKT and PI3K signalling inhibition. Further, 2-DGtolDC preferentially secrete IL-10 rather than IL-12 upon Mtb-stimulation. Importantly, a single subcutaneous administration of 2-DGtolDC prevented experimental autoimmune uveoretinitis (EAU) in vivo. Inhibiting glycolysis of autologous tolDC prior to transfer may be a useful approach to providing stable tolDC therapy for autoimmune/immune-mediated diseases.


Assuntos
Células Dendríticas/metabolismo , Desoxiglucose/farmacologia , Glicólise/efeitos dos fármacos , Imunossupressores/farmacologia , Animais , Antígenos de Bactérias/imunologia , Doenças Autoimunes/tratamento farmacológico , Antígeno B7-2/metabolismo , Células da Medula Óssea/citologia , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/metabolismo , Proliferação de Células/efeitos dos fármacos , Células Dendríticas/citologia , Células Dendríticas/efeitos dos fármacos , Desoxiglucose/uso terapêutico , Antígenos de Histocompatibilidade Classe II/metabolismo , Imunossupressores/uso terapêutico , Interleucina-10/metabolismo , Ácido Láctico/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação Oxidativa/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos
11.
Complement Ther Med ; 49: 102217, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32147041

RESUMO

OBJECTIVE: Our review summarizes published literature of complementary and alternative medicine (CAM) used for the treatment of acute bronchitis in children. BACKGROUND: Acute bronchitis is one of the most frequent pediatric diseases and has high prevalence for in- and outpatient care. Acute bronchitis is mainly a viral-caused infection, but a high and inappropriate use of antibiotics has been demonstrated in many countries. As CAM therapies might reduce the use of antibiotics and can complement conventional therapies in children, they could be an appropriate treatment option. METHODS: A systematic literature search was conducted using general and complementary and alternative medicine (CAM)-specific databases. A search term including 65 CAM-associated definitions was applied. RESULTS: Literature search revealed 309 articles, whereby 18 articles hit search criteria. These clinical trials were subgrouped into the categories herbal medicine, anthroposophic medicine and homeopathy. The most often studied approaches are herbal remedies, in particular the Pelargonium sidoides extract, EPs® 7630. Its efficacy was demonstrated in three placebo-controlled trials and two observational studies. Anthroposophic approaches (mainly ribwort-containing remedies) were investigated in two controlled trials and three observational studies. Two studies were found investigating the homeopathic remedies Monapax® and Droperteel®. CONCLUSION: Study results indicate a favorable effect of investigated CAM approaches. However, only three of 18 studies were randomized controlled trials (RCTs), so a reliable statement on effectiveness was not possible and further RCTs are indispensable.


Assuntos
Bronquite/tratamento farmacológico , Terapias Complementares/métodos , Doença Aguda , Criança , Humanos , Estudos Observacionais como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto
12.
Bioresour Technol ; 296: 122264, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31706135

RESUMO

A thermal balance modeling framework is developed, based on heat transfer-resistance networks. The heat transfer model accounts for effects of digester- design, location and operation, including effects of solar irradiance, external heating and ambient climate. We demonstrate extendibility of the framework by using the model in dynamic simulations of substrate temperature for digesters comprising two very different designs. Digester designs modeled include fixed-dome, buried, uninsulated and unheated household digesters in Hanoi, Vietnam, and an industrial-scale anaerobic digester located at a wastewater treatment plant in Esbjerg, Denmark. The modeled temperature profiles were evaluated against measured substrate temperatures over long periods, from 7 months and up. For the two Hanoi digesters, root-mean-square-error were 1.43 °C and 0.92 °C, with Nash-Sutcliffe model efficiency coefficients (NS-C) of 0.87 and 0.93 respectively. For the industrial digester in Esbjerg root-mean-square-error was 0.48 °C with an NS-C of 0.94. The model was not calibrated prior simulation, suggesting good predictive performance.


Assuntos
Biocombustíveis , Temperatura Alta , Anaerobiose , Reatores Biológicos , Dinamarca , Metano , Vietnã
13.
Eur J Pharm Sci ; 129: 181-189, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30639399

RESUMO

Liposomes are vesicular preparations that improve bioavailability of many pharmaceuticals, used even in ocular therapy. In addition, it is well documented that vesicular carriers could affect the photodegradation of molecules encapsulated inside, which is especially important for drugs that may exhibit phototoxicity when they are applied topically on sensitive light-exposed tissues. In this study, we investigated the effect of ciprofloxacin encapsulation into liposomes on its photodegradation, phototoxicity and photogenotoxicity in vitro at the concentration ranges applied in ophthalmology. We tested two variants of liposomes: large unilamellar vesicles (LUV) and multilamellar vesicles (MLV) in comparison to antibiotic solutions without phospholipids (CPX). On the basis of our research, the kinetics of ciprofloxacin photolysis was the fastest in formulations with vesicles with low drug-to-lipid ratio. Depending on vesicles type (drug-to-lipid ratio, MLV or LUV) and time of irradiation different degradants were produced. We proposed structures of the novel ciprofloxacin photolysis products characteristic for vesicles. We did not notice any photoprotective effect of application of ciprofloxacin encapsulation into liposomes, but it significantly affected the photodegradation product profile of the drug and the Photo-Irritation-Factor of the vesicular preparations. In the MTT and micronucleus assays impact of encapsulation was not as clearly visible.


Assuntos
Ciprofloxacina/química , Lipossomos/química , Fotólise/efeitos dos fármacos , Antibacterianos/química , Disponibilidade Biológica , Química Farmacêutica/métodos , Dermatite Fototóxica , Soluções/química
14.
Nurs Forum ; 53(1): 27-34, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28815609

RESUMO

The academic-practice gap in nursing is well documented. Academe is criticized for producing nurses insufficiently prepared to fully participate in patient care. Practice settings are criticized for having unrealistic expectations of new graduates. This article is based on a review of the literature and an exploration of contemporary practices used to bridge academic and practice partnerships. Differences in outcome expectations for new graduates between academe and practice are outlined and consequences of the gap for new graduates, patients, and employers are discussed. Five specific strategies to address the gap are discussed, with the primary realm and responsibility for two falling to education, one to practice, and two to both. Strategies discussed include increased use of simulated learning in nursing education; disruptive innovations in education that promote learner-centered active learning; extended orientation/Transition to Practice Programs for new graduates; dedicated education units; and academic service partnerships. Current literature suggests the viewpoints of academic and practice leaders continue to appear divergent. Closing the gap will require a dedicated and coordinated response from both academe and clinical practice.


Assuntos
Competência Clínica/normas , Educação Baseada em Competências/métodos , Bacharelado em Enfermagem/normas , Bacharelado em Enfermagem/tendências , Lacunas da Prática Profissional/normas , Humanos , Estudantes de Enfermagem , Estados Unidos
15.
ACS Chem Neurosci ; 9(2): 306-319, 2018 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-29043770

RESUMO

N-Methyl-d-aspartate receptors (NMDARs) are ionotropic glutamate receptors that mediate excitatory synaptic transmission and have been implicated in numerous neurological disorders. NMDARs typically comprise two GluN1 and two GluN2 subunits. The four GluN2 subtypes (GluN2A-GluN2D) have distinct functional properties and gene expression patterns, which contribute to diverse functional roles for NMDARs in the brain. Here, we present a series of GluN2C/2D-selective negative allosteric modulators built around a N-aryl benzamide (NAB) core. The prototypical compound, NAB-14, is >800-fold selective for recombinant GluN2C/GluN2D over GluN2A/GluN2B in Xenopus oocytes and has an IC50 value of 580 nM at recombinant GluN2D-containing receptors expressed in mammalian cells. NAB-14 inhibits triheteromeric (GluN1/GluN2A/GluN2C) NMDARs with modestly reduced potency and efficacy compared to diheteromeric (GluN1/GluN2C/GluN2C) receptors. Site-directed mutagenesis suggests that structural determinants for NAB-14 inhibition reside in the GluN2D M1 transmembrane helix. NAB-14 inhibits GluN2D-mediated synaptic currents in rat subthalamic neurons and mouse hippocampal interneurons, but has no effect on synaptic transmission in hippocampal pyramidal neurons, which do not express GluN2C or GluN2D. This series possesses some druglike physical properties and modest brain permeability in rat and mouse. Altogether, this work identifies a new series of negative allosteric modulators that are valuable tools for studying GluN2C- and GluN2D-containing NMDAR function in brain circuits, and suggests that the series has the potential to be developed into therapies for selectively modulating brain circuits involving the GluN2C and GluN2D subunits.


Assuntos
Benzamidas/farmacologia , Antagonistas de Aminoácidos Excitatórios/farmacologia , Hipocampo/efeitos dos fármacos , Interneurônios/efeitos dos fármacos , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Regulação Alostérica , Animais , Benzamidas/química , Antagonistas de Aminoácidos Excitatórios/química , Feminino , Células HEK293 , Hipocampo/metabolismo , Humanos , Interneurônios/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Mutagênese Sítio-Dirigida , Oócitos , Estrutura Secundária de Proteína , Ratos Sprague-Dawley , Receptores de N-Metil-D-Aspartato/genética , Receptores de N-Metil-D-Aspartato/metabolismo , Relação Estrutura-Atividade , Transmissão Sináptica/efeitos dos fármacos , Transmissão Sináptica/fisiologia , Técnicas de Cultura de Tecidos , Xenopus laevis
16.
Opt Express ; 25(10): 11414-11435, 2017 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-28788823

RESUMO

High energy laser systems are ultimately limited by laser-induced damage to their critical components. This is especially true of damage to critical fused silica optics, which grows rapidly upon exposure to additional laser pulses. Much progress has been made in eliminating damage precursors in as-processed fused silica optics (the advanced mitigation process, AMP3), and very high damage resistance has been demonstrated in laboratory studies. However, the full potential of these improvements has not yet been realized in actual laser systems. In this work, we explore the importance of additional damage sources-in particular, particle contamination-for fused silica optics fielded in a high-performance laser environment, the National Ignition Facility (NIF) laser system. We demonstrate that the most dangerous sources of particle contamination in a system-level environment are laser-driven particle sources. In the specific case of the NIF laser, we have identified the two important particle sources which account for nearly all the damage observed on AMP3 optics during full laser operation and present mitigations for these particle sources. Finally, with the elimination of these laser-driven particle sources, we demonstrate essentially damage free operation of AMP3 fused silica for ten large optics (a total of 12,000 cm2 of beam area) for shots from 8.6 J/cm2 to 9.5 J/cm2 of 351 nm light (3 ns Gaussian pulse shapes). Potentially many other pulsed high energy laser systems have similar particle sources, and given the insight provided by this study, their identification and elimination should be possible. The mitigations demonstrated here are currently being employed for all large UV silica optics on the National Ignition Facility.

17.
Mol Metab ; 6(8): 845-853, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28752048

RESUMO

OBJECTIVE: Cardiovascular disease (CVD) is the most prevalent cause of mortality among patients with Type 1 or Type 2 diabetes, due to accelerated atherosclerosis. Recent evidence suggests a strong link between atherosclerosis and insulin resistance due to impaired insulin receptor (IR) signaling. Moreover, inflammatory cells, in particular macrophages, play a key role in pathogenesis of atherosclerosis and insulin resistance in humans. We hypothesized that inhibiting the activity of protein tyrosine phosphatase 1B (PTP1B), the major negative regulator of the IR, specifically in macrophages, would have beneficial anti-inflammatory effects and lead to protection against atherosclerosis and CVD. METHODS: We generated novel macrophage-specific PTP1B knockout mice on atherogenic background (ApoE-/-/LysM-PTP1B). Mice were fed standard or pro-atherogenic diet, and body weight, adiposity (echoMRI), glucose homeostasis, atherosclerotic plaque development, and molecular, biochemical and targeted lipidomic eicosanoid analyses were performed. RESULTS: Myeloid-PTP1B knockout mice on atherogenic background (ApoE-/-/LysM-PTP1B) exhibited a striking improvement in glucose homeostasis, decreased circulating lipids and decreased atherosclerotic plaque lesions, in the absence of body weight/adiposity differences. This was associated with enhanced phosphorylation of aortic Akt, AMPKα and increased secretion of circulating anti-inflammatory cytokine interleukin-10 (IL-10) and prostaglandin E2 (PGE2), without measurable alterations in IR phosphorylation, suggesting a direct beneficial effect of myeloid-PTP1B targeting. CONCLUSIONS: Here we demonstrate that inhibiting the activity of PTP1B specifically in myeloid lineage cells protects against atherosclerotic plaque formation, under atherogenic conditions, in an ApoE-/- mouse model of atherosclerosis. Our findings suggest for the first time that macrophage PTP1B targeting could be a therapeutic target for atherosclerosis treatment and reduction of CVD risk.


Assuntos
Aterosclerose/metabolismo , Macrófagos/metabolismo , Placa Aterosclerótica/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 1/genética , Quinases Proteína-Quinases Ativadas por AMP , Animais , Apolipoproteínas E/genética , Aterosclerose/patologia , Células Cultivadas , Dinoprostona/metabolismo , Feminino , Interleucina-10/metabolismo , Masculino , Camundongos , Proteínas Quinases/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 1/deficiência , Proteína Tirosina Fosfatase não Receptora Tipo 1/metabolismo
18.
Sci Data ; 3: 160082, 2016 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-27727246

RESUMO

We present the data from a crowdsourced project seeking to replicate findings in independent laboratories before (rather than after) they are published. In this Pre-Publication Independent Replication (PPIR) initiative, 25 research groups attempted to replicate 10 moral judgment effects from a single laboratory's research pipeline of unpublished findings. The 10 effects were investigated using online/lab surveys containing psychological manipulations (vignettes) followed by questionnaires. Results revealed a mix of reliable, unreliable, and culturally moderated findings. Unlike any previous replication project, this dataset includes the data from not only the replications but also from the original studies, creating a unique corpus that researchers can use to better understand reproducibility and irreproducibility in science.


Assuntos
Princípios Morais , Reprodutibilidade dos Testes , Humanos
19.
Rofo ; 188(4): 353-8, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26716403

RESUMO

UNLABELLED: On February 26th, 2013 the patient law became effective in Germany. Goal of the lawmakers was a most authoritative case law for liability of malpractice and to improve enforcement of the rights of the patients. The following article contains several examples detailing legal situation. By no means should these discourage those persons who treat patients. Rather should they be sensitized to to various aspects of this increasingly important field of law. To identify relevant sources according to judicial standard research was conducted including first- and second selection. Goal was the identification of jurisdiction, literature and other various analyses that all deal with liability of malpractice and patient law within the field of Interventional Radiology--with particular focus on transarterial chemoembolization of the liver and related procedures. In summary, 89 different sources were included and analyzed. The individual who treats a patient is liable for an error in treatment if it causes injury to life, the body or the patient's health. Independent of the error in treatment the individual providing medical care is liable for mistakes made in the context of obtaining informed consent. Prerequisite is the presence of an error made when obtaining informed consent and its causality for the patient's consent for the treatment. Without an effective consent the treatment is considered illegal whether it was free of treatment error or not. The new patient law does not cause material change of the German liablity of malpractice law. KEY POINTS: •On February 26th, 2013 the new patient law came into effect. Materially, there was no fundamental remodeling of the German liability for medical malpractice. •Regarding a physician's liability for medical malpractice two different elements of an offence come into consideration: for one the liability for malpractice and, in turn, liability for errors made during medical consultation in the process of obtaining informed consent. •Forensic practice shows that patients frequently enforce both offences concurrently.


Assuntos
Consentimento Livre e Esclarecido/legislação & jurisprudência , Responsabilidade Legal , Erros Médicos/legislação & jurisprudência , Médicos/legislação & jurisprudência , Radiografia Intervencionista/normas , Radiologia Intervencionista/legislação & jurisprudência , Alemanha , Regulamentação Governamental
20.
Med Klin Intensivmed Notfmed ; 111(2): 92-7, 2016 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-26065385

RESUMO

BACKGROUND: Ethical and medical criteria in the decision-making process of withholding or withdrawal of life support therapy in critically ill patients present a great challenge in intensive care medicine. OBJECTIVES: The purpose of this work was to assess medical and ethical criteria that influence the decision-making process for changing the aim of therapy in critically ill cardiac surgery patients. MATERIALS AND METHODS: A questionnaire was distributed to all German cardiac surgery centers (n = 79). All clinical directors, intensive care unit (ICU) consultants and ICU head nurses were asked to complete questionnaires (n = 237). RESULTS: In all, 86 of 237 (36.3 %) questionnaires were returned. Medical reasons which influence the decision-making process for changing the aim of therapy were cranial computed tomography (cCT) with poor prognosis (91.9 %), multi-organ failure (70.9 %), and failure of assist device therapy (69.8 %). Concerning ethical reasons, poor expected quality of life (48.8 %) and the presumed patient's wishes (40.7 %) were reported. There was a significant difference regarding the perception of the three different professional groups concerning medical and ethical criteria as well as the involvement in the decision-making process. CONCLUSION: In critically ill cardiac surgery patients, medical reasons which influence the decision-making process for changing the aim of therapy included cCT with poor prognosis, multi-organ failure, and failure of assist device therapy. Further studies are mandatory in order to be able to provide adequate answers to this difficult topic.


Assuntos
Procedimentos Cirúrgicos Cardíacos/ética , Cuidados Críticos/ética , Técnicas de Apoio para a Decisão , Ética Médica , Cuidados para Prolongar a Vida/ética , Suspensão de Tratamento/ética , Diretivas Antecipadas/ética , Procedimentos Cirúrgicos Cardíacos/mortalidade , Causas de Morte , Alemanha , Inquéritos Epidemiológicos , Humanos , Comunicação Interdisciplinar , Colaboração Intersetorial , Futilidade Médica/ética , Insuficiência de Múltiplos Órgãos/mortalidade , Insuficiência de Múltiplos Órgãos/terapia , Equipe de Assistência ao Paciente/ética , Consentimento Presumido/ética , Inquéritos e Questionários
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