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1.
Molecules ; 27(3)2022 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-35163848

RESUMEN

Robust and easy-to-use NMR sensor technology is proposed for accurate, on-site determination of fat and protein contents in milk. The two parameters are determined using fast consecutive 1H and 35Cl low-field NMR experiments on milk samples upon the 1:1 addition of a low-cost contrast solution. Reliable and accurate measurements are obtained without tedious calibrations and the need for extensive database information and may readily be conducted by non-experts in production site environments. This enables on-site application at farms or dairies, or use in laboratories harvesting significant reductions in costs and time per analysis as compared to wet-chemistry analysis. The performance is demonstrated for calibration samples, various supermarket milk products, and raw milk samples, of which some were analyzed directly in the milking room. To illustrate the wide application range, the supermarket milk products included both conventionally/organically produced, lactose-free milk, cow's, sheep's and goat's milk, homogenized and unhomogenized milk, and a broad nutrient range (0.1-9% fat, 1-6% protein). Excellent agreement between NMR measurements and reference values, without corrections or changes in calibration for various products and during extensive periods of experiment conduction (4 months) demonstrates the robustness of the procedure and instrumentation. For the raw milk samples, correlations between NMR and IR, NMR and wet-chemistry, as well as IR and wet-chemistry results, show that NMR, in terms of accuracy, compares favorably with the other methods.


Asunto(s)
Grasas/análisis , Espectroscopía de Resonancia Magnética/métodos , Proteínas de la Leche/análisis , Leche/química , Animales , Bovinos , Femenino , Cabras , Ovinos
2.
Zentralbl Chir ; 144(3): 305-321, 2019 Jun.
Artículo en Alemán | MEDLINE | ID: mdl-31167271

RESUMEN

The therapy of rib fractures is controversially discussed. Neither does an osteosynthesis have to be performed for each individual rib fracture, nor is the internal splinting by ventilation or respiratory therapy sufficient for each patient. Rib fractures are common in polytrauma patients after car and motorcycle accidents or falls from great heights. However, rib fractures are also increasingly occurring in older patients with falls from low heights. Anamnesis and clinical examination are groundbreaking for the diagnosis and therapy decision of rib fractures. In radiological diagnostics, projection radiography comes first, followed by sonography and CT. Computed tomography should be required for planning an operation. Accompanying injuries must be taken into account when deciding on therapy. We see a complicated organ injury, dislocated rib serial fractures, flail chest and respiratory insufficiency as indications for rib stabilization. As a relative indication for rib stabilization, we see a high suffering pressure due to pain and an intrathoracic volume restriction due to dislocated rib serial fractures. New osteosynthesis material and minimally invasive techniques standardize the procedure and minimize surgical trauma. In any case, adequate pain and respiratory therapy are always crucial for successful treatment.


Asunto(s)
Tórax Paradójico , Insuficiencia Respiratoria , Fracturas de las Costillas , Humanos , Radiografía , Fracturas de las Costillas/terapia
3.
ACS Omega ; 6(27): 17335-17341, 2021 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-34278119

RESUMEN

The optimal processing of animal slurry with a minimal environmental impact either as an organic fertilizer or as an energy source for biogas production fundamentally requires accurate, fast, cost-effective, and mobile analytical techniques for the measurement of nitrogen and phosphorus in large volumes of liquid animal slurry. Based on more than 300 different slurries from different species and origins, we provide here an extensive analysis of low-field NMR and standard laboratory measurements for animal slurry analysis. It is found that low-field NMR provides higher precision than wet chemistry laboratory measurements for ammonium nitrogen and total nitrogen, while it provides slightly lower precision for total phosphorus measurements. Low-field NMR may, through a square-root dependency between time and precision, be adapted for analysis at farms, in slurry tankers/transporters, in biogas digesters, or in laboratories.

5.
Med Klin (Munich) ; 102(1): 59-63, 2007 Jan 15.
Artículo en Alemán | MEDLINE | ID: mdl-17221354

RESUMEN

BACKGROUND: Bronchopulmonary disease due to inhalation of smoke from open woodfires represents a major health problem in developing countries. Due to increasing migration such patients also present to medical services in Europe. CASE REPORT AND DISCUSSION: An 84-year-old Afghan housewife who never smoked nor has a history of exposure to inorganic dusts, presents with chronic obstructive pulmonary disease (COPD) in association with bronchial anthracosis and stenosis of a bronchus. The complaints are found to be caused by chronic inhalation of smoke from an open woodfire which was used for cooking. The main complaints of "woodsmoke-associated lung disease" are cough und dyspnea with bronchial obstruction. Radiology and bronchoscopy usually reveal changes which are similar to pneumoconiosis of miners but without patients' relevant exposure. There is a frequent association of anthracotic bronchial stenosis and infection with tuberculosis. CONCLUSION: Since patients rarely recognize the risks of woodsmoke inhalation, they hardly report their exposure. Thus, the anamnesis is crucial to establish the right diagnosis and guide the patient to the appropriate diagnostic and therapeutic procedures.


Asunto(s)
Antracosilicosis/etiología , Enfermedades Bronquiales/etiología , Carbón Orgánico/efectos adversos , Culinaria , Incendios , Enfermedad Pulmonar Obstructiva Crónica/etiología , Lesión por Inhalación de Humo/etiología , Afganistán/etnología , Anciano de 80 o más Años , Antracosilicosis/diagnóstico , Antracosilicosis/patología , Biopsia , Bronquios/patología , Enfermedades Bronquiales/diagnóstico , Enfermedades Bronquiales/patología , Diagnóstico Diferencial , Emigración e Inmigración , Femenino , Alemania , Humanos , Pulmón/patología , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Enfermedad Pulmonar Obstructiva Crónica/patología , Mucosa Respiratoria/patología , Lesión por Inhalación de Humo/diagnóstico , Lesión por Inhalación de Humo/patología , Tomografía Computarizada por Rayos X
6.
Ultrason Sonochem ; 22: 235-42, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25066472

RESUMEN

Ultrasound is considered to be an ignition source according to international standards, setting a threshold value of 1mW/mm(2) [1] which is based on theoretical estimations but which lacks experimental verification. Therefore, it is assumed that this threshold includes a large safety margin. At the same time, ultrasound is used in a variety of industrial applications where it can come into contact with explosive atmospheres. However, until now, no explosion accidents have been reported in connection with ultrasound, so it has been unclear if the current threshold value is reasonable. Within this paper, it is shown that focused ultrasound coupled into a liquid can in fact ignite explosive atmospheres if a specific target positioned at a liquid's surface converts the acoustic energy into a hot spot. Based on ignition tests, conditions could be derived that are necessary for an ultrasonically triggered explosion. These conditions show that the current threshold value can be significantly augmented.

7.
Lab Chip ; 4(6): 654-7, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15570380

RESUMEN

Laminar flow in microfluidic chambers was used to construct low (one dimensional) density arrays suitable for miniaturized biochemical assays. By varying the ratio of flows of two guiding streams flanking a sample stream, precise focusing and positioning of the latter was achieved, and reactive species carried in the sample stream were deposited on functionalized chip surfaces as discrete 50 microm wide lanes. Using different model systems we have confirmed the method's suitability for qualitative screening and quantification tasks in receptor-ligand assays, recording biotin-streptavidin interactions, DNA-hybridization and DNA-triplex formation. The system is simple, fast, reproducible, flexible, and has small sample requirements.


Asunto(s)
Análisis de Inyección de Flujo/métodos , Inmunoensayo/métodos , Técnicas Analíticas Microfluídicas/métodos , Microfluídica/métodos , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Mapeo de Interacción de Proteínas/métodos , Análisis de Inyección de Flujo/instrumentación , Inmunoensayo/instrumentación , Técnicas Analíticas Microfluídicas/instrumentación , Microfluídica/instrumentación , Miniaturización/métodos , Análisis de Secuencia por Matrices de Oligonucleótidos/instrumentación , Mapeo de Interacción de Proteínas/instrumentación
8.
BMC Biotechnol ; 3: 10, 2003 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-12875662

RESUMEN

BACKGROUND: The interest in microfluidics and surface patterning is increasing as the use of these technologies in diverse biomedical applications is substantiated. Controlled molecular and cellular surface patterning is a costly and time-consuming process. Methods for keeping multiple separate experimental conditions on a patterned area are, therefore, needed to amplify the amount of biological information that can be retrieved from a patterned surface area. We describe, in three examples of biomedical applications, how this can be achieved in an open microfluidic system, by hydrodynamically guiding sample fluid over biological molecules and living cells immobilized on a surface. RESULTS: A microfluidic format of a standard assay for cell-membrane integrity showed a fast and dose-dependent toxicity of saponin on mammalian cells. A model of the interactions of human mononuclear leukocytes and endothelial cells was established. By contrast to static adhesion assays, cell-cell adhesion in this dynamic model depended on cytokine-mediated activation of both endothelial and blood cells. The microfluidic system allowed the use of unprocessed blood as sample material, and a specific and fast immunoassay for measuring the concentration of C-reactive protein in whole blood was demonstrated. CONCLUSION: The use of hydrodynamic guiding made multiple and dynamic experimental conditions on a small surface area possible. The ability to change the direction of flow and produce two-dimensional grids can increase the number of reactions per surface area even further. The described microfluidic system is widely applicable, and can take advantage of surfaces produced by current and future techniques for patterning in the micro- and nanometer scale.


Asunto(s)
Inmunoensayo/métodos , Microquímica/métodos , Animales , Proteína C-Reactiva/metabolismo , Células CHO , Adhesión Celular/efectos de los fármacos , Línea Celular , Membrana Celular/efectos de los fármacos , Células Inmovilizadas/citología , Células Inmovilizadas/efectos de los fármacos , Células Inmovilizadas/metabolismo , Quimiocinas/metabolismo , Cricetinae , Endotelio Vascular/citología , Endotelio Vascular/efectos de los fármacos , Endotelio Vascular/metabolismo , Humanos , Leucocitos Mononucleares/citología , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/metabolismo , Saponinas/farmacología , Propiedades de Superficie , Factor de Necrosis Tumoral alfa/farmacología
9.
Heart Surg Forum ; 6(5): 353-7, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-14721808

RESUMEN

BACKGROUND: The T graft is achieved by the end-to-side implantation of a free arterial graft into the left internal thoracic artery, which remains in situ. Which conduit is best suited as the free graft is still being discussed. METHODS: Two groups of patients are compared. The right internal thoracic artery (RITA) was used as a free graft in group I (n = 129), and the radial artery was used in group II (n = 84). RESULTS: The RITA was used more often with male patients (P < .02) and with patients presenting a reduced left ventricular ejection fraction (P < .03). The average number of coronary anastomoses per patient was higher in group II than in group I (P < .002). There were no significant differences between the groups in early mortality (0.8% in group I and 1.2% in group II) and morbidity. Postoperative chest tube output was significantly higher in group I than in group II (P < .05). The mean follow-up time was 35.2 +/-28.3 months. There were no significant differences regarding late mortality (6.9% in group I and 5.3% in group II) and the recurrence of angina (group I, 6 cases or 5.5%; group II, 3 cases or 4.2%). Because of the recurrence of angina or questionable chest pain in 22 patients, angiography was performed, and results showed a patency rate of 90.9% in group I and 93.1% in group II. CONCLUSIONS: Based on our experience, we advise using the RITA as a free graft with tall men and also in patients with a reduced left ventricular ejection fraction, diabetes, and obesity. The radial artery should be used with small women if there is a high risk of bleeding and if several coronary anastomoses are necessary.


Asunto(s)
Arterias Mamarias/trasplante , Revascularización Miocárdica/métodos , Arteria Radial/trasplante , Estatura , Femenino , Estudios de Seguimiento , Humanos , Anastomosis Interna Mamario-Coronaria/métodos , Masculino , Tasa de Supervivencia
10.
Interact Cardiovasc Thorac Surg ; 18(4): 511-8, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24368551

RESUMEN

A best evidence topic in cardiovascular surgery was written according to a structured protocol. The question addressed was whether patients with severe asymptomatic carotid and coronary artery diseases should undergo simultaneous carotid endarterectomy (CEA) and coronary artery bypass grafting (CABG). A total of 624 papers were found using the reported search, of which 20 represent the best evidence to answer the clinical question. The author, journal, date and country of publication, patient group studied, study type, relevant outcomes, results and study results of these papers are tabulated. Previous cohort studies showed mixed results, while advocating for the necessity of a randomized controlled trial (RCT). A recent RCT showed that patients undergoing prophylactic or simultaneous CEA + CABG had lower rates of stroke (0%) compared with delayed CEA 1-3 months after CABG (7.7%), without significant perioperative mortality difference. This study included patients with unilateral severe (>70%) asymptomatic carotid stenosis requiring CABG. An earlier partly randomized trial also showed better outcomes for patients undergoing simultaneous procedures (P = 0.045). Interestingly, systematic reviews previously failed to show compelling evidence supporting prophylactic CEA. This could be partly due to the fact that these reviews collectively analyse different cohort qualities. Neurological studies have, however, shown reduced cognitive and phonetic quality and function in patients with unilateral and bilateral asymptomatic carotid artery stenosis. Twenty-one RCTs comparing lone carotid artery stenting (CAS) and CEA informed the American Heart Association guidelines, which declared CAS comparable with CEA for symptomatic and asymptomatic carotid stenosis (CS). However, the risk of death/stroke for CAS alone is double that for CEA alone in the acute phase following onset of symptoms, while CEA alone is associated with a doubled risk of myocardial infarction. There is, however, no significant difference for combined 30-day risk of death/stroke/myocardial infarction. Outcomes of hybrid or simultaneous CAS/CABG procedures show comparable results, albeit from rather small cohorts. While current evidence leans towards simultaneous CEA/CABG, the emergence of hybrid operating theatres in various institutions may allow larger cohorts with subsequent significant data on simultaneous CAS/CABG. A randomized controlled trial comparing both approaches would be crucial in informing future updates of existing guidelines.


Asunto(s)
Angioplastia , Estenosis Carotídea/terapia , Puente de Arteria Coronaria , Enfermedad de la Arteria Coronaria/cirugía , Endarterectomía Carotidea , Anciano , Angioplastia/efectos adversos , Angioplastia/instrumentación , Enfermedades Asintomáticas , Benchmarking , Estenosis Carotídea/complicaciones , Estenosis Carotídea/diagnóstico , Estenosis Carotídea/cirugía , Puente de Arteria Coronaria/efectos adversos , Enfermedad de la Arteria Coronaria/complicaciones , Enfermedad de la Arteria Coronaria/diagnóstico , Endarterectomía Carotidea/efectos adversos , Medicina Basada en la Evidencia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/etiología , Infarto del Miocardio/prevención & control , Selección de Paciente , Medición de Riesgo , Factores de Riesgo , Índice de Severidad de la Enfermedad , Stents , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/prevención & control , Resultado del Tratamiento
11.
J Cardiothorac Surg ; 7: 82, 2012 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-22947441

RESUMEN

BACKGROUND: Mitral Valve Repair (MVRP) has been shown to be significantly superior to Mitral Valve Replacement (MVR). Since the majority of repairs involve the Posterior Mitral Leaflet (PML) and not the Anterior Mitral Leaflet (AML), the monocuspidalisation of the Mitral Valve (MV) can be achieved with a bio-posterior leaflet that imitates a closed PML. This approach may have the benefit of restoring the competence of the MV without reducing its effective orifice area. METHODS: We have used a new concept and device, the MitroFixTM, to correct MV regurgitation due to pathology of the PML. The device comes with functional sizers both of which have identical shape and size. This allows the surgeon to pre-test the success of the restoration. From December 2006 to October 2011, 51 MitroFixTM devices were implanted at three institutions. RESULTS: The mean age of the patients (32 males and 19 females) was 67.7 years. 37 of them were in NYHA class III or IV and all patients suffered from severe mitral valve regurgitation (MR). 31 patients underwent combined surgery. Successful implantation of the MitroFix™ device was performed in 51/53 patients.Mean cross-clamp time was 63.6 min (range: 29-118 min). Six patients had additional reconstructive procedures of the AML (chordae transfer, neo-chordae, triangular resection). At discharge, 33 patients showed no MR in the TTE and 17 patients exhibited trivial (I) or moderate (II) MR. The mean gradient was 4.0 mmHg and mean EOA was 2.52cm^2 (range: 1.5-4.0cm2). All patients were classified as being in NYHA class I or II. CONCLUSION: The MitroFixTM Mitral Valve Restoration Device is a new concept that offers an effective treatment of MR. The restoration of the mitral valve with the MitroFix™ device offers the advantage of preserving the AML and providing good coaptation with a prosthetic PML. Importantly, this preliminary evaluation indicates a mean effective orifice area ( EOA ) of 2.5cm2 in MV receiving a MitroFix™ device, witch is higher than EOA resulting from MVR or MVRP. The present study has also shown that severe regurgitation due to ischemic/rheumatic MR, endocarditis and complex prolapse of the PML are clear candidates for correction with the MitroFix™. Larger studies and a longer follow up period are needed to validate these promising results.


Asunto(s)
Implantación de Prótesis de Válvulas Cardíacas/instrumentación , Prótesis Valvulares Cardíacas , Válvula Mitral/cirugía , Anciano , Anciano de 80 o más Años , Femenino , Implantación de Prótesis de Válvulas Cardíacas/métodos , Humanos , Masculino , Persona de Mediana Edad , Insuficiencia de la Válvula Mitral/cirugía
12.
Interact Cardiovasc Thorac Surg ; 5(4): 439-43, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17670611

RESUMEN

OBJECTIVES: Brain natriuretic peptide (BNP) is a valuable marker in heart failure and its therapy, for example cardiac resynchronization therapy (CRT). So far, one finding which is indicative for CRT is dyssynchrony of ventricular contraction obtained by echocardiography. The aim of this study was to show that BNP is also a helpful marker to help decide whether CRT is useful for patients after CABG. METHODS: Forty-two patients with a poor ejection fraction (<35%) underwent elective CABG. Twenty-eight of them received permanent biventricular stimulation for seven days after surgery. Before and on the first, third, seventh and tenth day after surgical treatment, the following parameters were established: left ventricular function obtained by transthoracic echocardiography, myocardium-specific enzymes (such as CK and CKMB), ECG and BNP. RESULTS: There was a very good correlation between the preoperative ejection fraction and BNP (r2=0.98, P<0.005). Patients who had received CRT after CABG had BNP levels similar to preoperative data on postoperative day 7. This decrease of the BNP values in the CRT-group is in accord with an increased left ventricular function as obtained by echocardiography. The control group, which had not received CRT, showed significantly higher BNP levels. CONCLUSIONS: Therefore, we conclude that BNP is a good marker to evaluate CRT in patients undergoing CABG. An extraordinary rise of the BNP level should lead to early therapeutic consequences like CRT. The significantly lower BNP level of the patients with heart failure who received CRT indicates a better prognosis.

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