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1.
J Inherit Metab Dis ; 47(4): 651-663, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38390655

RESUMEN

Phenylketonuria (PKU) is a congenital metabolic disorder that causes the systemic elevation of phenylalanine (Phe), which is neurotoxic and teratogenic. PKU is currently incurable, and management involves lifelong adherence to an unpalatable protein-restricted diet based on Phe-free amino acid mixtures. Seeking a palatable dietary alternative, we identified a Bacillus subtilis protein (GSP16O) with a well-balanced but low-Phe amino acid profile. We optimized the sequence and expressed a modified Phe-free version (GSP105) in Pseudomonas fluorescens, achieving yields of 20 g/L. The purified GSP105 protein has a neutral taste and smell, is highly soluble, and remains stable up to 80°C. Homozygous enu2 mice, a model of human PKU, were fed with diets containing either GSP105 or normal protein. The GSP105 diet led to normalization of blood Phe levels and brain monoamine neurotransmitter metabolites, and prevented maternal PKU. The GSP105 diet thus provides an alternative and efficacious dietary management strategy for PKU.


Asunto(s)
Fenilalanina , Fenilcetonurias , Proteínas Recombinantes , Fenilalanina/sangre , Animales , Fenilcetonurias/dietoterapia , Ratones , Humanos , Proteínas Recombinantes/administración & dosificación , Femenino , Modelos Animales de Enfermedad , Bacillus subtilis/metabolismo , Bacillus subtilis/genética , Proteínas en la Dieta/administración & dosificación , Dieta con Restricción de Proteínas , Proteínas Bacterianas/genética
2.
BMC Infect Dis ; 23(1): 349, 2023 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-37231332

RESUMEN

INTRODUCTION: Deep sternal wound infection is a rare but feared complication of median thoracotomies and is usually caused by microorganisms from the patient's skin or mucous membranes, the external environment, or iatrogenic procedures. The most common involved pathogens are Staphylococcus aureus, Staphylococcus epidermidis and gram-negative bacteria. We aimed to evaluate the microbiological spectrum of deep sternal wound infections in our institution and to establish diagnostic and treatment algorithms. METHODS: We retrospectively evaluated the patients with deep sternal wound infections at our institution between March 2018 and December 2021. The inclusion criteria were the presence of deep sternal wound infection and complete sternal osteomyelitis. Eighty-seven patients could be included in the study. All patients received a radical sternectomy, with complete microbiological and histopathological analysis. RESULTS: In 20 patients (23%) the infection was caused by S. epidermidis, in 17 patients (19.54%) by S. aureus, in 3 patients (3.45%) by Enterococcus spp., in 14 patients (16.09%) by gram-negative bacteria, while in 14 patients (16.09%) no pathogen could be identified. In 19 patients (21,84%) the infection was polymicrobial. Two patients had a superimposed Candida spp. INFECTION: Methicillin-resistant S. epidermidis was found in 25 cases (28,74%), while methicillin-resistant S. aureus was isolated in only three cases (3,45%). The average hospital stay for monomicrobial infections was 29.93 ± 13.69 days and for polymicrobial infections was 37.47 ± 19.18 (p = 0.03). Wound swabs and tissue biopsies were routinely harvested for microbiological examination. The increasing number of biopsies was associated with the isolation of a pathogen (4.24 ± 2.22 vs. 2.18 ± 1.6, p < 0,001). Likewise, the increasing number of wound swabs was also associated with the isolation of a pathogen (4.22 ± 3.34 vs. 2.40 ± 1.45, p = 0.011). The median duration of antibiotic treatment was 24.62 (4-90) days intravenous and 23.54 (4-70) days orally. The length of antibiotic treatment for monomicrobial infections was 22.68 ± 14.27 days intravenous and 44.75 ± 25.87 days in total and for polymicrobial infections was 31.65 ± 22.29 days intravenous (p = 0.05) and 61.29 ± 41.45 in total (p = 0.07). The antibiotic treatment duration in patients with methicillin-resistant Staphylococci as well as in patients who developed an infection relapse was not significantly longer. CONCLUSION: S. epidermidis and S. aureus remain the main pathogen in deep sternal wound infections. The number of wound swabs and tissue biopsies correlates with accurate pathogen isolation. With radical surgical treatment, the role of prolonged antibiotic treatment remains unclear and should be evaluated in future prospective randomized studies.


Asunto(s)
Procedimientos Quirúrgicos Cardíacos , Coinfección , Staphylococcus aureus Resistente a Meticilina , Osteomielitis , Humanos , Estudios Retrospectivos , Toracotomía , Staphylococcus aureus , Infección de la Herida Quirúrgica/microbiología , Coinfección/tratamiento farmacológico , Procedimientos Quirúrgicos Cardíacos/efectos adversos , Antibacterianos/uso terapéutico , Osteomielitis/tratamiento farmacológico , Osteomielitis/etiología
3.
Langenbecks Arch Surg ; 408(1): 188, 2023 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-37165212

RESUMEN

PURPOSE: Osteomyelitis of the sternum may arise either as a primary condition or secondary to median thoracotomy after cardiac surgery, with the latter being decidedly more frequent. Deep sternal wound infections appear as a complication of median thoracotomy in 0.2 to 4.4% of cases and may encompass the infection of the sternal bone. To date, there are no exhaustive histopathological studies of the sternal osteomyelitis. METHODS: Our work group developed a surgical technique to remove the complete infected sternal bone in deep sternal wound infections. We therefore prospectively examined the en bloc resected sternal specimens. Seven standard histological sections were made from the two hemisternums. RESULTS: Forty-seven sternums could be investigated. The median age of the patients in the cohort was 66 (45-81) years and there were 10 females and 37 males. Two methods were developed to examine the histological findings, with one model dividing the results in inflammatory and non-inflammatory, while the second method using a score from 0 to 5 to describe more precisely the intensity of the bone inflammation. The results showed the presence of inflammation in 76.6 to 93.6% of the specimens, depending on the section. The left manubrial sections were more prone to inflammation, especially when the left mammary artery was harvested. No further risk factors proved to have a statistical significance. CONCLUSION: Our study proved that the deep sternal wound infection may cause a ubiquitous inflammation of the sternal bone. The harvest of the left mammary artery may worsen the extent and intensity of infection.


Asunto(s)
Osteomielitis , Toracotomía , Masculino , Femenino , Humanos , Anciano , Anciano de 80 o más Años , Estudios Prospectivos , Toracotomía/efectos adversos , Osteomielitis/cirugía , Osteomielitis/complicaciones , Infección de la Herida Quirúrgica/epidemiología , Inflamación
4.
Mar Drugs ; 21(12)2023 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-38132926

RESUMEN

Chitin/chitosan and collagen are two of the most important bioactive compounds, with applications in the pharmaceutical, veterinary, nutraceutical, cosmetic, biomaterials, and other industries. When extracted from non-edible parts of fish and shellfish, by-catches, and invasive species, their use contributes to a more sustainable and circular economy. The present article reviews the scientific knowledge and publication trends along the marine chitin/chitosan and collagen value chains and assesses how researchers, industry players, and end-users can bridge the gap between scientific understanding and industrial applications. Overall, research on chitin/chitosan remains focused on the compound itself rather than its market applications. Still, chitin/chitosan use is expected to increase in food and biomedical applications, while that of collagen is expected to increase in biomedical, cosmetic, pharmaceutical, and nutritional applications. Sustainable practices, such as the reuse of waste materials, contribute to strengthen both value chains; the identified weaknesses include the lack of studies considering market trends, social sustainability, and profitability, as well as insufficient examination of intellectual property rights. Government regulations, market demand, consumer preferences, technological advancements, environmental challenges, and legal frameworks play significant roles in shaping both value chains. Addressing these factors is crucial for seizing opportunities, fostering sustainability, complying with regulations, and maintaining competitiveness in these constantly evolving value chains.


Asunto(s)
Quitina , Quitosano , Colágeno , Animales , Materiales Biocompatibles/economía , Quitina/economía , Quitosano/economía , Cosméticos , Preparaciones Farmacéuticas , Mariscos , Colágeno/economía
5.
Mar Drugs ; 17(8)2019 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-31374920

RESUMEN

Chitin is an abundant polysaccharide primarily produced as an industrial waste stream during the processing of crustaceans. Despite the limited applications of chitin, there is interest from the medical, agrochemical, food and cosmetic industries because it can be converted into chitosan and partially acetylated chitosan oligomers (COS). These molecules have various useful properties, including antimicrobial and anti-inflammatory activities. The chemical production of COS is environmentally hazardous and it is difficult to control the degree of polymerization and acetylation. These issues can be addressed by using specific enzymes, particularly chitinases, chitosanases and chitin deacetylases, which yield better-defined chitosan and COS mixtures. In this review, we summarize recent chemical and enzymatic approaches for the production of chitosan and COS. We also discuss a design-of-experiments approach for process optimization that could help to enhance enzymatic processes in terms of product yield and product characteristics. This may allow the production of novel COS structures with unique functional properties to further expand the applications of these diverse bioactive molecules.


Asunto(s)
Quitina/química , Quitosano/síntesis química , Crustáceos/química , Tecnología Química Verde/métodos , Amidohidrolasas/química , Animales , Quitinasas/química , Glicósido Hidrolasas/química , Residuos Industriales
6.
Biotechnol Lett ; 38(12): 2007-2014, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27623794

RESUMEN

Statistical experimental designs, also known as the "design of experiments" (DoE) approach, are widely used to improve not only technical processes but also to answer questions in the agricultural, medical and social sciences. Although many articles have been published about the application of DoE in these fields, few studies have addressed the use of DoE in the plant sciences, particularly in the context of plant cell suspension cultures (PCSCs). Compounds derived from PCSCs can be developed as pharmaceuticals, chemical feedstocks and cosmetic ingredients, and statistical experimental designs can be used to improve the productivity of the cells and the yield and/or quality of the target compounds in a cost efficient manner. In this article, we summarize recent findings concerning the application of statistical approaches to improve the performance of PCSCs and discuss the potential future applications of this approach.


Asunto(s)
Técnicas de Cultivo de Célula/métodos , Células Vegetales/metabolismo , Interpretación Estadística de Datos , Proyectos de Investigación
7.
Biotechnol Bioeng ; 112(2): 308-21, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25117428

RESUMEN

Tobacco BY-2 cells have emerged as a promising platform for the manufacture of biopharmaceutical proteins, offering efficient protein secretion, favourable growth characteristics and cultivation in containment under a controlled environment. The cultivation of BY-2 cells in disposable bioreactors is a useful alternative to conventional stainless steel stirred-tank reactors, and orbitally-shaken bioreactors could provide further advantages such as simple bag geometry, scalability and predictable process settings. We carried out a scale-up study, using a 200-L orbitally-shaken bioreactor holding disposable bags, and BY-2 cells producing the human monoclonal antibody M12. We found that cell growth and recombinant protein accumulation were comparable to standard shake flask cultivation, despite a 200-fold difference in cultivation volume. Final cell fresh weights of 300-387 g/L and M12 yields of ∼20 mg/L were achieved with both cultivation methods. Furthermore, we established an efficient downstream process for the recovery of M12 from the culture broth. The viscous spent medium prevented clarification using filtration devices, but we used expanded bed adsorption (EBA) chromatography with SP Sepharose as an alternative for the efficient capture of the M12 antibody. EBA was introduced as an initial purification step prior to protein A affinity chromatography, resulting in an overall M12 recovery of 75-85% and a purity of >95%. Our results demonstrate the suitability of orbitally-shaken bioreactors for the scaled-up cultivation of plant cell suspension cultures and provide a strategy for the efficient purification of antibodies from the BY-2 culture medium.


Asunto(s)
Anticuerpos Monoclonales/metabolismo , Reactores Biológicos , Células Vegetales/metabolismo , Proteínas Recombinantes/metabolismo , Anticuerpos Monoclonales/análisis , Anticuerpos Monoclonales/genética , Línea Celular , Humanos , Plantas Modificadas Genéticamente , Polisacáridos/metabolismo , Proteínas Recombinantes/análisis , Proteínas Recombinantes/genética , Nicotiana
8.
Plant Biotechnol J ; 12(1): 81-92, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24102775

RESUMEN

Synthetic linear antimicrobial peptides with cationic α-helical structures, such as BP100, are valuable as novel therapeutics and preservatives. However, they tend to be toxic when expressed at high levels as recombinant peptides in plants, and they can be difficult to detect and isolate from complex plant tissues because they are strongly cationic and display low extinction coefficient and extremely limited immunogenicity. We therefore expressed BP100 with a C-terminal tag which preserved its antimicrobial activity and demonstrated significant accumulation in plant cells. We used a fluorescent tag to trace BP100 following transiently expression in Nicotiana benthamiana leaves and showed that it accumulated in large vesicles derived from the endoplasmic reticulum (ER) along with typical ER luminal proteins. Interestingly, the formation of these vesicles was induced by BP100. Similar vesicles formed in stably transformed Arabidopsis thaliana seedlings, but the recombinant peptide was toxic to the host during latter developmental stages. This was avoided by selecting active BP100 derivatives based on their low haemolytic activity even though the selected peptides remained toxic to plant cells when applied exogenously at high doses. Using this strategy, we generated transgenic rice lines producing active BP100 derivatives with a yield of up to 0.5% total soluble protein.


Asunto(s)
Péptidos Catiónicos Antimicrobianos/metabolismo , Retículo Endoplásmico/metabolismo , Células Vegetales/metabolismo , Proteínas de Plantas/metabolismo , Péptidos Catiónicos Antimicrobianos/genética , Regulación de la Expresión Génica de las Plantas , Oryza/genética , Oryza/metabolismo , Proteínas de Plantas/genética , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/metabolismo , Nicotiana/genética , Nicotiana/metabolismo
9.
J Immunoassay Immunochem ; 35(3): 322-34, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24350651

RESUMEN

Non human antibodies administered to human patients often generate anti-antibody responses, leading in extreme cases to anaphylactic shock. Completely human antibodies are therefore favored over their murine, chimeric and humanized counterparts. However, the accurate evaluation of human antibodies on human tissue samples cannot be achieved using indirect immunohistochemical methods because of endogenous immunoglobulins that are co-detected by the secondary antibodies. Direct detection is often used instead, but this lacks the signal amplification conferred by the secondary antibody and is therefore less sensitive. We developed a simple fluorescence-based indirect immunohistochemical method that allows human primary antibodies bound specifically to their target antigens in human tissue samples to be detected clearly and without interfering background staining. This approach involves a biotinylated human primary antibody (H10(Biotin)) and Cy3-conjugated streptavidin (Strep(Cy3)). We tested the protocol using a human carcinoembryonic antigen (CEA) specific IgG1 (H10). We identified an exposure time threshold that allowed the elimination of low Strep(Cy3) background staining, yet achieved sufficient signal amplification to make our approach four times more sensitive than comparable direct immunohistochemical procedures. The principle of this indirect immunohistochemical assay should be transferable to other species allowing the specific and sensitive detection of any primary antibody on homologous tissues.


Asunto(s)
Anticuerpos Monoclonales , Antígeno Carcinoembrionario/análisis , Carcinoma/diagnóstico , Neoplasias del Colon/diagnóstico , Técnica del Anticuerpo Fluorescente Indirecta/métodos , Inmunoglobulina G , Animales , Anticuerpos Monoclonales/biosíntesis , Anticuerpos Monoclonales/química , Biotina/química , Biotinilación , Células CHO , Carbocianinas , Carcinoma/inmunología , Carcinoma/patología , Neoplasias del Colon/inmunología , Neoplasias del Colon/patología , Cricetulus , Células HEK293 , Humanos , Inmunoglobulina G/biosíntesis , Inmunoglobulina G/química , Ratones , Sensibilidad y Especificidad , Coloración y Etiquetado/métodos , Estreptavidina/química
10.
J Cardiothorac Surg ; 19(1): 25, 2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38268012

RESUMEN

BACKGROUND: Deep sternal wound infection (DSWI) is a rare, yet devastating complication after cardiac surgery. While the surgical treatment always implies the soft tissue and bone debridement, there is little data about this procedure. The aim of our study was to evaluate the impact of the radical sternectomy on the outcome in patients with DSWI and to identify the risk factors which could influence the result. The surgical techniques of piecemeal sternectomy and the newly developed en bloc sternectomy were also evaluated. METHODS: The study was developed as a retrospective cohort study. 86 patients with DSWI who received a radical sternal resection at our institution between March 2018 and December 2021 were included. RESULTS: The average age of the cohort was 67.3 ± 7.4 years, and 23.3% of patients were female. The average length of stay trended shorter after en bloc sternectomy (median 26 days) compared to piecemeal sternectomy (37 days). There were no significant differences between the piecemeal and en bloc sternal resection techniques. Anticoagulant and antiplatelet drugs had no significant influence on bleeding and transfusion rates. Obese patients showed an increased risk for postoperative bleeding requiring reintervention. Transfusion of packed red blood cells was significantly associated with lower hemoglobin values before surgery and ASA Class 4 compared to ASA Class 3. The in-hospital mortality was 9.3%, with female sex and reintervention for bleeding as significant risk factors. Nine patients developed an infection relapse as a chronic fistula at the level of clavicula or ribs, with ASA Class 4 as a risk factor. CONCLUSION: Radical sternectomy is a safe procedure to treat DSWI with compromised sternal bone. Both piecemeal and en bloc techniques ensure reliable results, while complications and mortality appear to be patient-related.


Asunto(s)
Anticoagulantes , Esternón , Humanos , Femenino , Persona de Mediana Edad , Anciano , Masculino , Estudios Retrospectivos , Esternón/cirugía , Mortalidad Hospitalaria , Obesidad
11.
Front Physiol ; 14: 1127624, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37324389

RESUMEN

Photoplethysmography (PPG) allows various statements about the physiological state. It supports multiple recording setups, i.e., application to various body sites and different acquisition modes, rendering the technique a versatile tool for various situations. Owing to anatomical, physiological and metrological factors, PPG signals differ with the actual setup. Research on such differences can deepen the understanding of prevailing physiological mechanisms and path the way towards improved or novel methods for PPG analysis. The presented work systematically investigates the impact of the cold pressor test (CPT), i.e., a painful stimulus, on the morphology of PPG signals considering different recording setups. Our investigation compares contact PPG recorded at the finger, contact PPG recorded at the earlobe and imaging PPG (iPPG), i.e., non-contact PPG, recorded at the face. The study bases on own experimental data from 39 healthy volunteers. We derived for each recording setup four common morphological PPG features from three intervals around CPT. For the same intervals, we derived blood pressure and heart rate as reference. To assess differences between the intervals, we used repeated measures ANOVA together with paired t-tests for each feature and we calculated Hedges' g to quantify effect sizes. Our analyses show a distinct impact of CPT. As expected, blood pressure shows a highly significant and persistent increase. Independently of the recording setup, all PPG features show significant changes upon CPT as well. However, there are marked differences between recording setups. Effect sizes generally differ with the finger PPG showing the strongest response. Moreover, one feature (pulse width at half amplitude) shows an inverse behavior in finger PPG and head PPG (earlobe PPG and iPPG). In addition, iPPG features behave partially different from contact PPG features as they tend to return to baseline values while contact PPG features remain altered. Our findings underline the importance of recording setup and physiological as well as metrological differences that relate to the setups. The actual setup must be considered in order to properly interpret features and use PPG. The existence of differences between recording setups and a deepened knowledge on such differences might open up novel diagnostic methods in the future.

12.
Ann Biomed Eng ; 50(12): 1837-1845, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35773416

RESUMEN

Coronary artery disease represents a leading cause of death worldwide, to which the coronary artery bypass graft (CABG) is the main method of treatment in advanced multiple vessel disease. The use of the internal mammary artery (IMA) as a graft insures an improved long-term survival, but impairment of chest wall perfusion often leads to surgical site infection and increased morbidity and mortality. Infrared thermography (IRT) has established itself in the past decades as a non-invasive diagnostic technique. The applications vary from veterinary to human medicine and from head to toe. In this study we used IRT in 42 patients receiving CABG to determine the changes in skin surface temperature preoperatively, two hours, 24 h and 6 days after surgery. The results showed a significant and independent drop of surface temperature 2 h after surgery on the whole surface of the chest wall, as well as a further reduction on the left side after harvesting the IMA. The temperature returned to normal after 24 h and remained so after 6 days. The study has shown that IRT is sufficiently sensitive to demonstrate the known, subtle reduction in chest wall perfusion associated with IMA harvesting.


Asunto(s)
Enfermedad de la Arteria Coronaria , Pared Torácica , Humanos , Pared Torácica/diagnóstico por imagen , Pared Torácica/cirugía , Puente de Arteria Coronaria/métodos , Diagnóstico por Imagen , Perfusión
13.
Materials (Basel) ; 14(5)2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33804506

RESUMEN

Friction stir spot welding is an emerging spot-welding technology that offers opportunities for joining a wide range of materials with minimum energy consumption. To increase productivity, the present work addresses production challenges and aims to find solutions for the lap-welding of multiple ultrathin sheets with maximum productivity. Two convex tools with different edge radii were used to weld four ultrathin sheets of AA5754-H111 alloy each with 0.3 mm thickness. To understand the influence of tool geometries and process parameters, coefficient of friction (CoF), microstructure and mechanical properties obtained with the Vickers microhardness test and the small punch test were analysed. A scanning acoustic microscope was used to assess weld quality. It was found that the increase of tool radius from 15 to 22.5 mm reduced the dwell time by a factor of three. Samples welded with a specific tool were seen to have no delamination and improved mechanical properties due to longer stirring time. The rotational speed was found to be the most influential parameter in governing the weld shape, CoF, microstructure, microhardness and weld efficiency. Low rotational speeds caused a 14.4% and 12.8% improvement in joint efficiency compared to high rotational speeds for both tools used in this investigation.

14.
Sci Rep ; 11(1): 23353, 2021 12 02.
Artículo en Inglés | MEDLINE | ID: mdl-34857851

RESUMEN

Plant secondary metabolites are widely used in the food, cosmetic and pharmaceutical industries. They can be extracted from sterile grown plant cell suspension cultures, but yields and quality strongly depend on the cultivation environment, including optimal illumination. Current shaking incubators do not allow different light wavelengths, intensities and photoperiods to be tested in parallel. We therefore developed LEDitSHAKE, a system for multiplexed customized illumination within a single shaking incubator. We used 3D printing to integrate light-emitting diode assemblies into flask housings, allowing 12 different lighting conditions (spectrum, intensity and photoperiod) to be tested simultaneously. We did a proof of principle of LEDitSHAKE using the system to optimize anthocyanin production in grapevine cell suspension cultures. The effect of 24 different light compositions on the total anthocyanin content of grapevine cell suspension cultures was determined using a Design of Experiments approach. We predicted the optimal lighting conditions for the upregulation and downregulation of 30 anthocyanins and found that short-wavelength light (blue, UV) maximized the concentration of most anthocyanins, whereas long-wavelength light (red) had the opposite effect. Therefore our results demonstrate proof of principle that the LEDitSHAKE system is suitable for the optimization of processes based on plant cell suspension cultures.


Asunto(s)
Antocianinas/metabolismo , Técnicas de Cultivo de Célula/normas , Luz , Iluminación/normas , Células Vegetales/metabolismo , Vitis/metabolismo , Células Cultivadas , Suspensiones , Vitis/química
15.
Front Microbiol ; 12: 643275, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34025604

RESUMEN

A novel severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) emerged in China in December 2019, causing an ongoing, rapidly spreading global pandemic. Worldwide, vaccination is now expected to provide containment of the novel virus, resulting in an antibody-mediated immunity. To verify this, serological antibody assays qualitatively as well as quantitatively depicting the amount of generated antibodies are of great importance. Currently available test methods are either laboratory based or do not have the ability to indicate an estimation about the immune response. To overcome this, a novel and rapid serological magnetic immunodetection (MID) point-of-care (PoC) assay was developed, with sensitivity and specificity comparable to laboratory-based DiaSorin Liaison SARS-CoV-2 S1/S2 IgG assay. To specifically enrich human antibodies against SARS-CoV-2 in immunofiltration columns (IFCs) from patient sera, a SARS-CoV-2 S1 antigen was transiently produced in plants, purified and immobilized on the IFC. Then, an IgG-specific secondary antibody could bind to the retained antibodies, which was finally labeled using superparamagnetic nanoparticles. Based on frequency magnetic mixing technology (FMMD), the magnetic particles enriched in IFC were detected using a portable FMMD device. The obtained measurement signal correlates with the amount of SARS-CoV-2-specific antibodies in the sera, which could be demonstrated by titer determination. In this study, a MID-based assay could be developed, giving qualitative as well as semiquantitative results of SARS-CoV-2-specific antibody levels in patient's sera within 21 min of assay time with a sensitivity of 97% and a specificity of 92%, based on the analysis of 170 sera from hospitalized patients that were tested using an Food and Drug Administration (FDA)-certified chemiluminescence assay.

16.
Clin Neurol Neurosurg ; 207: 106809, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34274657

RESUMEN

BACKGROUND: In neurosurgical perioperative treatment, especially in connection with subarachnoid hemorrhage (SAH), the prophylactic anticoagulation (AC) regimen is still considered controversial. The goal of this retrospective study was to assess how the time point of low-molecular-weight heparin (LMWH) initiation (ToH) affects ischemic and hemorrhagic events after SAH. METHODS: 370 patients who received acute treatment for non-traumatic SAH between 2011 and 2018 were included, and 208 patients were followed up after 12 months. We assessed how the ToH affects ischemic and hemorrhagic events as well as outcome scores. Statistical analysis was performed using the Mann-Whitney U-Test, the chi-squared test, Fisher's exact test, and univariate binomial logistic regression. P-values below 0.05 were considered statistically significant. RESULTS: The incidence of systemic ischemia was 4.6%, cerebral ischemia 33.5%, and intracranial rebleeding 14.6%. Delaying ToH (measured in hours) increases systemic ischemia (p = 0.009). The odds ratio for the impact of delayed anticoagulation on systemic ischemia is 1.013 per hour (95%CI of OR 1.001-1.024). ToH has no influence on cerebral ischemia or intracranial rebleeding. Early anticoagulation was associated with a more favorable Glasgow Outcome Score 12 months after discharge (ToH within 48 h: p = 0.006). ToH did not affect mortality or readmission rates. CONCLUSIONS: Initiating prophylactic AC with LMWH later than 48 h after aneurysm repair or admission impairs outcomes 12 months after discharge. It might be safe for patients with non-traumatic SAH to be anticoagulated with prophylactic doses of heparin within 24 h after admission or the treatment of source of bleeding (SoB). Early AC with prophylactic LMWH does not promote rebleeding.


Asunto(s)
Anticoagulantes/administración & dosificación , Isquemia Encefálica/epidemiología , Heparina de Bajo-Peso-Molecular/administración & dosificación , Hemorragias Intracraneales/epidemiología , Hemorragia Subaracnoidea/complicaciones , Anciano , Isquemia Encefálica/etiología , Isquemia Encefálica/prevención & control , Femenino , Escala de Consecuencias de Glasgow , Humanos , Incidencia , Hemorragias Intracraneales/etiología , Isquemia/epidemiología , Isquemia/etiología , Isquemia/prevención & control , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
17.
Exp Lung Res ; 36(9): 538-47, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20874224

RESUMEN

Inhalation of perfluorohexane vapor (PFH) and high-frequency oscillatory ventilation (HFOV) both have been shown to improve lung function in acute lung injury (ALI). Their combination implies synergistic action. The authors investigated technical aspects of PFH vaporization during HFOV and effects on gas exchange in a pilot study of experimental ALI. Eighteen anesthetized sheep were randomly assigned to HFOV or HFOV with PFH inhalation after oleic acid-induced ALI. HFOV was set to a continuous distending pressure of 25 cm H2O, and an oscillation of 80 to 100 cm H2O at a frequency of 5 Hz. PFH vapor was delivered by means of bypassed high-flow oxygen through a thin endotracheal tube. PFH concentration was measured by infrared absorption. Blood gases and hemodynamic data were taken. PaO2 significantly increased from 9.1 ± 0.9 to 32.7 ± 9.5 kPa (mean ± SEM) in the HFOV group and from 12.5 ± 1.1 to 27.0 ± 6.8 kPa in the HFOV PFH group. PaCO2 significantly decreased from 6.3 ± 0.3 to 5.5 ± 0.5 kPa in the HFOV group and from 5.7 ± 0.4 to 4.9 ± 0.5 kPa in the HFOV PFH group. Changes in gas exchange were not different between groups. These results show that the inhalation of PFH during HFOV is technically feasible, but did not enhance gas exchange in a 210-minute observation period of experimental ALI.


Asunto(s)
Lesión Pulmonar Aguda/tratamiento farmacológico , Fluorocarburos/administración & dosificación , Ventilación de Alta Frecuencia/métodos , Ventilación Liquida/métodos , Lesión Pulmonar Aguda/inducido químicamente , Lesión Pulmonar Aguda/fisiopatología , Animales , Modelos Animales de Enfermedad , Exposición por Inhalación , Ácido Oléico/toxicidad , Proyectos Piloto , Intercambio Gaseoso Pulmonar/efectos de los fármacos , Ovinos , Volatilización
18.
PLoS One ; 15(9): e0238387, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32870937

RESUMEN

OBJECTIVE: Anticoagulation (AC) is a critical topic in perioperative and post-bleeding management. Nevertheless, there is a lack of data about the safe, judicious use of prophylactic and therapeutic anticoagulation with regard to risk factors and the cause and modality of brain tissue damage as well as unfavorable outcomes such as postoperative hemorrhage (PH) and thromboembolic events (TE) in neurosurgical patients. We therefore present retrospective data on perioperative anticoagulation in meningioma surgery. METHODS: Data of 286 patients undergoing meningioma surgery between 2006 and 2018 were analyzed. We followed up on anticoagulation management, doses and time points of first application, laboratory values, and adverse events such as PH and TE. Pre-existing medication and hemostatic conditions were evaluated. The time course of patients was measured as overall survival, readmission within 30 days after surgery, as well as Glasgow Outcome Scale (GOS) and modified Rankin Scale (mRS). Statistical analysis was performed using multivariate regression. RESULTS: We carried out AC with Fraxiparin and, starting in 2015, Tinzaparin in weight-adapted recommended prophylactic doses. Delayed (216 ± 228h) AC was associated with a significantly increased rate of TE (p = 0.026). Early (29 ± 21.9h) prophylactic AC, on the other hand, did not increase the risk of PH. We identified additional risk factors for PH, such as blood pressure maxima, steroid treatment, and increased white blood cell count. Patients' outcome was affected more adversely by TE than PH (+3 points in modified Rankin Scale in TE vs. +1 point in PH, p = 0.001). CONCLUSION: Early prophylactic AC is not associated with an increased rate of PH. The risks of TE seem to outweigh those of PH. Early postoperative prophylactic AC in patients undergoing intracranial meningioma resection should be considered.


Asunto(s)
Anticoagulantes/efectos adversos , Hemorragias Intracraneales/etiología , Neoplasias Meníngeas/cirugía , Meningioma/cirugía , Anciano , Anticoagulantes/administración & dosificación , Esquema de Medicación , Femenino , Alemania/epidemiología , Humanos , Hemorragias Intracraneales/epidemiología , Modelos Logísticos , Masculino , Persona de Mediana Edad , Atención Perioperativa/efectos adversos , Hemorragia Posoperatoria/epidemiología , Hemorragia Posoperatoria/etiología , Estudios Retrospectivos , Factores de Riesgo , Tromboembolia/epidemiología , Tromboembolia/etiología
19.
Sci Rep ; 10(1): 16464, 2020 10 05.
Artículo en Inglés | MEDLINE | ID: mdl-33020579

RESUMEN

Remote imaging photoplethysmography (iPPG) senses the cardiac pulse in outer skin layers and is responsive to mean arterial pressure and pulse pressure in critically ill patients. Whether iPPG is sufficiently sensitive to monitor cutaneous perfusion is not known. This study aimed at determining the response of iPPG to changes in cutaneous perfusion measured by  Laser speckle imaging (LSI). Thirty-seven volunteers were engaged in a cognitive test known to evoke autonomic nervous activity and a Heat test. Simultaneous measurements of iPPG and LSI were taken at baseline and during cutaneous perfusion challenges. A perfusion index (PI) was calculated to assess iPPG signal strength. The response of iPPG to the challenges and its relation to LSI were determined. PI of iPPG significantly increased in response to autonomic nervous stimuli and to the Heat test by 5.8% (p = 0.005) and 11.1% (p < 0.001), respectively. PI was associated with LSI measures of cutaneous perfusion throughout experiments (p < 0.001). iPPG responses to study task correlated with those of LSI (r = 0.62, p < 0.001) and were comparable among subjects. iPPG is sensitive to autonomic nervous activity in volunteers and is closely associated with cutaneous perfusion.


Asunto(s)
Fotopletismografía/métodos , Piel/fisiopatología , Adulto , Presión Sanguínea/fisiología , Diagnóstico por Imagen/métodos , Femenino , Frecuencia Cardíaca/fisiología , Humanos , Masculino , Monitoreo Fisiológico/métodos , Perfusión/métodos , Voluntarios
20.
Front Plant Sci ; 10: 720, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31244868

RESUMEN

Over the last three decades, the expression of recombinant proteins in plants and plant cells has been promoted as an alternative cost-effective production platform. However, the market is still dominated by prokaryotic and mammalian expression systems, the former offering high production capacity at a low cost, and the latter favored for the production of complex biopharmaceutical products. Although plant systems are now gaining widespread acceptance as a platform for the larger-scale production of recombinant proteins, there is still resistance to commercial uptake. This partly reflects the relatively low yields achieved in plants, as well as inconsistent product quality and difficulties with larger-scale downstream processing. Furthermore, there are only a few cases in which plants have demonstrated economic advantages compared to established and approved commercial processes, so industry is reluctant to switch to plant-based production. Nevertheless, some plant-derived proteins for research or cosmetic/pharmaceutical applications have reached the market, showing that plants can excel as a competitive production platform in some niche areas. Here, we discuss the strengths of plant expression systems for specific applications, but mainly address the bottlenecks that must be overcome before plants can compete with conventional systems, enabling the future commercial utilization of plants for the production of valuable proteins.

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