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1.
J Dairy Res ; 90(4): 393-397, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38224020

RESUMO

When implementing the transition from regular milk production to the dry period, drying off is mostly conducted simply by abrupt cessation of milking. Efforts to reduce milk synthesis before cessation of milking aim to reduce stress in cows as well as to lower the risk of mastitis. A previous study demonstrated that incomplete milking during the last ten days of lactation gradually reduced the milk yield of healthy, high-yielding cows. However, a reduction period of ten days might be too long for cows with lower yields. Therefore, a follow-up study was conducted on an organic dairy research farm with a lower average milk yield. We investigated whether automated incomplete milking can reduce milk synthesis within one week without impairing the health status of udder quarters infected with minor pathogens. Before drying off, 15 German-Holstein cows with 58 lactating quarters, 21 of which were infected with minor pathogens (coagulase-negative Staphylococci (CNS) and Corynebacterium bovis), were milked twice daily using the software module AutoDry (GEA Farm Technologies) with the 5%-step-down-per-day-program. The level of udder emptying was gradually reduced over 8-10 milkings beginning at a mean milk yield of 17.2 ± 4.4 kg d-1. During the last three milkings before drying off, milking clusters were automatically removed when a milk flow rate of 0.3 kg min-1 was reached. Quarter fore-milk samples were collected at two time points (14 d before and at the date of the last milking, ie drying off) and were analysed for mastitis pathogens and somatic cell count. The gradual reduced emptying of the udder induced a clear decline in milk yield by 0.8 ± 0.3 kg d-1. Within the reduction period, the somatic cell count of quarter foremilk did not change regardless of the infection status. Furthermore, no cow suffered from clinical mastitis. Thus, a reduction in milk synthesis could be achieved within less than one week before drying off without any impairment in udder health of cows, even when infected with minor mastitis pathogens.


Assuntos
Doenças dos Bovinos , Mastite Bovina , Feminino , Bovinos , Animais , Lactação , Glândulas Mamárias Animais/microbiologia , Seguimentos , Indústria de Laticínios , Leite/microbiologia , Contagem de Células/veterinária , Mastite Bovina/microbiologia
2.
J Dairy Sci ; 105(10): 8342-8353, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36055842

RESUMO

Drying-off practices to reduce milk production before dry-off are gaining attention because high milk yields at dry-off are becoming more common and increase the risk to cow health and welfare during the dry period. Incomplete milking for the last days before dry-off is one approach for reducing milk production. We conducted an online survey to determine the currently used drying-off practices on Swiss dairy farms and to identify the adoption potential of integrating incomplete milking before dry-off. In March 2021, the online survey was sent to a representative sample of 1,974 Swiss dairy farmers. A total of 518 completed questionnaires were analyzed. The mean number of dairy cows per farm was 39 (range: 11-140 cows). Thirty-five percent of cows produced considerable quantities of milk (>15 kg/d) at dry-off, and milk yield at dry-off increased with increasing annual milk yield. Abrupt dry-off was applied on 45% of the farms. The participants reported observing behavioral changes of cows such as increased vocalizations and decreased lying time associated with dry-off. Selective dry cow therapy was applied on 74% of the farms, and 44% of the participants indicated the use of antibiotics at dry-off as being "rather often," "often," or "always." Correlation analysis revealed that with increasing annual milk yields, the frequency of observed behavioral changes and antibiotic use at dry-off increased as well. Therefore, drying-off approaches that reduce milk production while supporting cow welfare are needed. We found that farmers showed an interest in testing the presented drying-off approach of incomplete milking. In addition, the farmers indicated that they would be more willing to test incomplete milking before dry-off if it became available for automated use in milking parlors or robots. Uncertainties regarding udder health appeared to be the main barrier for the adoption potential of this approach.


Assuntos
Indústria de Laticínios , Lactação , Animais , Antibacterianos/uso terapêutico , Bovinos , Fazendas , Feminino , Humanos , Glândulas Mamárias Animais , Leite , Suíça
3.
Sensors (Basel) ; 21(4)2021 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-33671216

RESUMO

The prediction of health disorders is the goal of many sensor systems in dairy farming. Although mastitis and lameness are the most common health disorders in dairy cows, these diseases or treatments are a rare event related to a single day and cow. A number of studies already developed and evaluated models for classifying cows in need of treatment for mastitis and lameness with machine learning methods, but few have illustrated the effects of the positive predictive value (PPV) on practical application. The objective of this study was to investigate the importance of low-frequency treatments of mastitis or lameness for the applicability of these classification models in practice. Data from three German dairy farms contained animal individual sensor data (milkings, activity, feed intake) and were classified using machine learning models developed in a previous study. Subsequently, different risk criteria (previous treatments, information from milk recording, early lactation) were designed to isolate high-risk groups. Restricting selection to cows with previous mastitis or hoof treatment achieved the highest increase in PPV from 0.07 to 0.20 and 0.15, respectively. However, the known low daily risk of a treatment per cow remains the critical factor that prevents the reduction of daily false-positive alarms to a satisfactory level. Sensor systems should be seen as additional decision-support aid to the farmers' expert knowledge.


Assuntos
Criação de Animais Domésticos/instrumentação , Doenças dos Bovinos/diagnóstico , Indústria de Laticínios , Coxeadura Animal/diagnóstico , Mastite/diagnóstico , Animais , Bovinos , Fazendas , Feminino , Lactação , Leite
4.
Angew Chem Int Ed Engl ; 60(52): 27264-27270, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34672411

RESUMO

Molecular spoked wheels with intraannular functionalizable pillars are synthesized in a modular approach. The functionalities at their ends are variable, and a propargyl alcohol, a [6,6]-phenyl-C61-butyrate, and a perylene monoimide are investigated. All compounds form two-dimensional crystals on highly oriented pyrolytic graphite at the solid-liquid interface. As determined by submolecularly resolved scanning tunneling microscopy, the pillars adopt equilibrium distances of 6.0 nm. The fullerene has a residual mobility, limited by the length of the flexible connector unit. The experimental results are supported and rationalized by molecular dynamics simulations. These also show that, in contrast, the more rigidly attached perylene monoimide units remain oriented along the surface normal and maintain a smallest distance of 2 nm above the graphite substrate. The robust packing concept also holds for cocrystals with molecular hexagons that expand the pillar-pillar distances by 15 % and block unspecific intercalation.

5.
Sensors (Basel) ; 20(14)2020 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-32664417

RESUMO

The aim of this study was to develop classification models for mastitis and lameness treatments in Holstein dairy cows as the target variables based on continuous data from herd management software with modern machine learning methods. Data was collected over a period of 40 months from a total of 167 different cows with daily individual sensor information containing milking parameters, pedometer activity, feed and water intake, and body weight (in the form of differently aggregated data) as well as the entered treatment data. To identify the most important predictors for mastitis and lameness treatments, respectively, Random Forest feature importance, Pearson's correlation and sequential forward feature selection were applied. With the selected predictors, various machine learning models such as Logistic Regression (LR), Support Vector Machine (SVM), K-nearest neighbors (KNN), Gaussian Naïve Bayes (GNB), Extra Trees Classifier (ET) and different ensemble methods such as Random Forest (RF) were trained. Their performance was compared using the receiver operator characteristic (ROC) area-under-curve (AUC), as well as sensitivity, block sensitivity and specificity. In addition, sampling methods were compared: Over- and undersampling as compensation for the expected unbalanced training data had a high impact on the ratio of sensitivity and specificity in the classification of the test data, but with regard to AUC, random oversampling and SMOTE (Synthetic Minority Over-sampling) even showed significantly lower values than with non-sampled data. The best model, ET, obtained a mean AUC of 0.79 for mastitis and 0.71 for lameness, respectively, based on testing data from practical conditions and is recommended by us for this type of data, but GNB, LR and RF were only marginally worse, and random oversampling and SMOTE even showed significantly lower values than without sampling. We recommend the use of these models as a benchmark for similar self-learning classification tasks. The classification models presented here retain their interpretability with the ability to present feature importances to the farmer in contrast to the "black box" models of Deep Learning methods.


Assuntos
Coxeadura Animal/diagnóstico , Coxeadura Animal/terapia , Aprendizado de Máquina , Mastite/diagnóstico , Mastite/terapia , Animais , Teorema de Bayes , Bovinos , Indústria de Laticínios , Feminino , Leite , Sensibilidade e Especificidade
6.
Sensors (Basel) ; 18(8)2018 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-30081480

RESUMO

In the last decades, there has been an increasing interest in animal protection and welfare issues. Heart rate variability (HRV) measurement with portable heart rate monitors on cows has established itself as a suitable method for assessing physiological states. However, more forward-looking technologies, already successfully applied to evaluate HRV data, are pushing the market. This study examines the validity and usability of collecting HRV data by exchanging the Polar watch V800 as a receiving unit of the data compared to a custom smartphone application on cows. Therefore, both receivers tap one signal sent by the Polar H7 transmitter simultaneously. Furthermore, there is a lack of suitable methods for the preparation and calculation of HRV parameters, especially for livestock. A method is presented for calculating more robust time domain HRV parameters via median formation. The comparisons of the respective simultaneous recordings were conducted after artifact correction for time domain HRV parameters. High correlations (r = 0.82⁻0.98) for cows as well as for control data set in human being (r = 0.98⁻0.99) were found. The utilization of smart devices and the robust method to determine time domain HRV parameters may be suitable to generate valid HRV data on cows in field-based settings.


Assuntos
Computação em Nuvem , Indústria de Laticínios/métodos , Frequência Cardíaca/fisiologia , Monitorização Fisiológica/veterinária , Smartphone , Animais , Bovinos , Feminino , Humanos
7.
Appl Opt ; 55(33): 9370-9377, 2016 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-27869835

RESUMO

This paper presents the conception and implementation of a variable diameter ring-cutting system for a CO2 laser with a working wavelength of 10.6 µm. The laser-cutting system is adapted to an observation zoom microscope for combined use and is applicable for the extraction of small circular areas from polymer films, such as forensic adhesive tapes in a single shot. As an important characteristic for our application, the variable diameter ring-cutting system provides telecentricity in the target area. Ring diameters are continuously tunable between 500 µm and 2 mm. A minimum width of less than 20 µm was found for the ring profile edge. The basic characteristics of the system, including telecentricity, were experimentally evaluated and demonstrated by cutting experiments on different polymer tapes and further exemplary samples.

8.
Int J Mol Sci ; 15(2): 2906-15, 2014 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-24557583

RESUMO

Adiponectin and intracellular 5'adenosine monophosphate-activated protein kinase (AMPK) are important modulators of glucose and fat metabolism. Cinnamon exerts beneficial effects by improving insulin sensitivity and blood lipids, e.g., through increasing adiponectin concentrations and AMPK activation. The underlying mechanism is unknown. The Gi/Go-protein-coupled receptor (GPR) 109A stimulates adiponectin secretion after binding its ligand niacin. Trans-cinnamic acid (tCA), a compound of cinnamon is another ligand. We hypothesize whether AMPK activation and adiponectin secretion by tCA is transmitted by GPR signaling. Differentiated 3T3-L1 cells were incubated with pertussis toxin (PTX), an inhibitor of G(i)/G(o)-protein-coupling, and treated with different tCA concentrations. Treatment with tCA increased adiponectin and the pAMPK/AMPK ratio (p ≤ 0.001). PTX incubation abolished the increased pAMPK/AMPK ratio and adiponectin secretion. The latter remained increased compared to controls (p ≤ 0.002). tCA treatment stimulated adiponectin secretion and AMPK activation; the inhibitory effect of PTX suggests GPR is involved in tCA stimulated signaling.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Adiponectina/metabolismo , Cinamatos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Células 3T3-L1 , Adipócitos/citologia , Adipócitos/metabolismo , Animais , Isomerismo , Camundongos , Toxina Pertussis/toxicidade , Fosforilação/efeitos dos fármacos , Receptores Acoplados a Proteínas G/metabolismo
9.
Int J Syst Evol Microbiol ; 63(Pt 12): 4495-4501, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23907219

RESUMO

Two groups of Gram-stain positive, aerobic bacterial strains were isolated from raw cow's milk, from a milking machine and from bulk tank milk. Based on their 16S rRNA gene sequences these isolates formed two distinct groups within the genus Corynebacterium. The sequence similarities of the isolates to the type strains of species of the genus Corynebacterium were below 98.4%. The presence of menaquinones MK-8(H2) and MK-9(H2), the predominant fatty acid 18:1 cis 9 and a polar lipid pattern with several phospholipids but without aminolipids was in accord with the characteristics of this genus. The results of DNA-DNA hybridization, biochemical tests and chemotaxonomic properties allowed genotypic and phenotypic differentiation of the strains from all known species of the genus Corynebacterium. Therefore, the isolates were assigned to two novel species of this genus for which the names Corynebacterium frankenforstense sp. nov. (type strain ST18(T) =DSM 45800(T) = CCUG 63371(T)), and Corynebacterium lactis sp. nov. (type strain RW2-5(T) = DSM 45799(T) = CCUG 63372(T)) are proposed, respectively.


Assuntos
Corynebacterium/classificação , Microbiologia de Alimentos , Leite/microbiologia , Filogenia , Animais , Técnicas de Tipagem Bacteriana , Bovinos , Corynebacterium/genética , Corynebacterium/isolamento & purificação , DNA Bacteriano/genética , Ácidos Graxos/química , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
10.
BMC Public Health ; 13: 959, 2013 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-24131544

RESUMO

BACKGROUND: The federal campaign Wir gegen Viren [Us against viruses] promoted hygiene in Germany during the influenza A H1N1 pandemic in 2009. The intervention aimed to encourage people to protect themselves against respiratory infections by simple means of hygiene behaviour. Quantitative research was carried out to outline changes in hygiene perception of the population over time, and to find out whether the potential hygiene perception changes were consistent to the federal campaign about hygiene or not. METHODS: To determine changes in the hygiene perception of the population, two cross-sectional telephone surveys were held, each one with n = 2006 participants. The initial survey was carried out before the influenza A H1N1 pandemic in calendar week 49-51 in 2008 and the second in week 48 in 2009 directly after the peak of the pandemic in Germany. The questionnaire contained indicators about perceived hand hygiene efficacy, preference for coughing into the sleeve, propensity for presenteeism while showing symptoms of a cold and acceptance of hygiene masks. RESULTS: The proportion of people who perceive the efficacy of hand washing as "very good" increased significantly from 50.9% in 2008 to 61.1% in 2009. The proportion of people who perceive coughing into the sleeve as the best way to cough increased even more dramatically from 4.8% in 2008 to 38.3% in 2009. In contrast the propensity for presenteeism decreased significantly: The proportion of people who state that they always report to work while they show symptoms of a cold decreased from 50.8% in 2008 to 40.9% in 2009. Acceptance of hygiene masks has not changed significantly from 2008 to 2009. CONCLUSIONS: The results revealed changes in hygiene perception during influenza A H1N1 pandemic in Germany. The changes we found are in accordance with the hygiene recommendations given by the federal campaign Wir gegen Viren [Us against viruses]. Results can constitute a practical benchmark for future research about hygiene perception and hygiene promotion for adults. A pivotal question is: does the increase in hygiene perception persist after the pandemic has ceased?


Assuntos
Desinfecção das Mãos/tendências , Conhecimentos, Atitudes e Prática em Saúde , Higiene , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Influenza Humana/prevenção & controle , Pandemias , Adolescente , Adulto , Estudos Transversais , Feminino , Alemanha/epidemiologia , Inquéritos Epidemiológicos/métodos , Humanos , Influenza Humana/epidemiologia , Masculino , Análise Multivariada , Inquéritos e Questionários , Adulto Jovem
11.
Arch Kriminol ; 228(1-2): 11-9, 2011.
Artigo em Alemão | MEDLINE | ID: mdl-21850882

RESUMO

Genital swabs play an important role in cases of alleged sexual assault. The aim of our study was to see if epithelial cells from the vagina, glans penis, or mouth could be distinguished on the basis of size. Vaginal swabs were taken from 12 women in different phases of their menstrual cycles; penile swabs were taken from 5 men, and mouth swabs were taken from 6 men and 6 women. For each swab, a sample was smeared across a microscope slide and allowed to dry. The dried epithelial samples were then viewed without any further processing with a "SteReoLumar.V12" stereo microscope. The microscope slide surfaces were divided into grids and all single epithelial cells whose contours could be clearly distinguished were photographed. The maximum diameter for each photographed cell was digitally determined using the Axiovision software. In total, 995 vaginal epithelial cells, 211 penile epithelial cells, 329 male oral epithelial cells, and 525 female oral epithelial cells were measured. Menstrual cycle phase did not affect vaginal epithelial cell diameter. The mean vaginal epithelial cell diameter was 63.95 microm (min. = 28.08 microm, max. = 108.06 microm, s = 11.50 microm). The mean penile epithelial cell diameter was 39.24 microm (min. = 28.38 microm, max. = 51.02 microm, s = 4.84 microm). The diameter of oral epithelial cells hardly differed for both sexes, although the female cells were, on the whole, slightly larger. On the basis of these results, it is not possible to conclude that epithelial cells of less than a certain diameter found in the assessment of a vaginal swab must be of penile origin. It is also not possible to usefully distinguish vaginal epithelial cells from male or female oral epithelial cells on the basis of the diameter. However, finding epithelial cells with a diameter distinctly greater than 50 microm in a penile swab sample suggests the presence of vaginal or oral epithelial cells. Epithelial cells examined with the presented method can be used without restrictions for further examinations, such as single-cell DNA analysis after single-cell picking with the micromanipulator developed by Aura Optik (Jena).


Assuntos
Tamanho Celular , Células Epiteliais/classificação , Células Epiteliais/citologia , Mucosa Bucal/citologia , Pênis/citologia , Delitos Sexuais/legislação & jurisprudência , Vagina/citologia , Prova Pericial/legislação & jurisprudência , Feminino , Humanos , Masculino , Valor Preditivo dos Testes , Esfregaço Vaginal
12.
Vet Immunol Immunopathol ; 228: 110113, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32871407

RESUMO

The transition period, from pregnancy to lactation, implies comprehensive metabolic and endocrine changes including a systemic inflammatory reaction and oxidative stress around calving in dairy cows. The aim of the present study was a longitudinal characterization of the serum concentration of acute phase proteins (APP), i.e., haptoglobin (Hp), serum amyloid A (SAA) and acidic glycoprotein (AGP), as well as of markers for oxidative stress in another large dairy animal, i.e. water buffalo, during the transition from late pregnancy to early lactation. As indicators of oxidative status, derivatives of reactive oxygen metabolites (dROM), ferric reducing ability (FRAP), thiobarbituric acid reactive substances (TBARS), and advanced oxidation protein products (AOPP) were determined in serum. Indicators for metabolic stress included nonesterified fatty acids (NEFA), ß-hydroxybutyrate (BHB) and adiponectin. Bovine specific ELISA methods for Hp and adiponectin were adapted and validated for their application to water buffalo samples. Blood samples were collected weekly from 11 pluriparous water buffalo cows (lactation number 4.6 ± 1.6; daily milk yield 9.0 ± 1.9 kg; means ± SD) from 6 weeks (wk) ante partum (ap) until 8 wk post partum (pp). The maximum concentrations of Hp were observed in wk 1 pp, followed by a decrease towards values lower than before calving starting from wk 3 pp. The concentrations of SAA also peaked in wk 1 pp and then returned to basal values. The AGP serum concentrations increased suddenly from the first to the second wk pp and remained elevated for all the observation period. Indicators of oxidative status which changed in concentration during the transition period were dROM, AOPP and the oxidative stress index (OSi) (dROM/FRAP ratio). Briefly, dROM and AOPP values were lower pp as compared to ap, and OSi was largely following the pattern of dROM due to the constant FRAP values. The TBARS values did not change during the observation period. From the metabolic indicators, adiponectin was not changing with time, whereas greater NEFA and BHB values were observed ap than pp. The time course of NEFA and of some indicators for oxidative status (dROM, OSi and AOPP) point to greater metabolic load in late pregnancy as compared with the first wk of lactation - contrary to the common situation in dairy cows. Both BHB and NEFA values remained below the thresholds applied for dairy cows to define subclinical or clinical ketosis, thus indicating that the buffaloes included in this study were not under metabolic stress. The increase in concentration of the APP around calving supports the concept that an inflammatory reaction is a physiological epiphenomenon of the onset of lactation in water buffalos that is independent of metabolic stress.


Assuntos
Proteínas de Fase Aguda/metabolismo , Búfalos/sangue , Lactação/sangue , Estresse Oxidativo , Prenhez/sangue , Animais , Biomarcadores/sangue , Ácidos Graxos não Esterificados/metabolismo , Feminino , Haptoglobinas/metabolismo , Gravidez , Espécies Reativas de Oxigênio/sangue , Proteína Amiloide A Sérica/metabolismo
13.
Anal Biochem ; 394(1): 135-7, 2009 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-19602419

RESUMO

A rapid mechanical micropreparation technique has been developed to isolate multicellular glands, here from Nepenthes pitchers, based on a microdissection platform. The method is an alternative to laser capture dissection because fresh plant tissue can be used directly without previous fixation. Subsequent experiments, such as polymerase chain reaction (PCR)-based detection of an individual gene encoding a thaumatin-like protein and RNA extraction for gene expression analysis, have been successfully added to prove the quality of the prepared biological material. The procedure described is adaptable to a broad range of plant species and should find wide application in the preparation of multicellular glands or other tissues.


Assuntos
Magnoliopsida/anatomia & histologia , Microdissecção/métodos , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Magnoliopsida/genética , Microscopia , Reação em Cadeia da Polimerase , Fatores de Tempo
15.
Biointerphases ; 13(1): 011004, 2018 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-29382205

RESUMO

The primary goal of our investigation was the development of a versatile immobilization matrix based on archaeal tetraether lipids that meets the most important prerequisites to render an implant surface bioactive by binding specific functional groups or functional polymers with the necessary flexibility and an optimal spatial arrangement to be bioavailable. From this point of view, it appears obvious that numerous efforts made recently to avoid initial bacterial adhesion on catheter surfaces as an important prerequisite of material associated infection episodes have shown only a limited efficiency since the bioactive entities could not be presented in an optimal conformation and a stable density. A significant improvement of this situation can be achieved by highly specific biomimetic modifications of the catheter surfaces. The term "biomimetic" originates from the fact that specific archaeal tetraether lipids were introduced to form a membrane analog monomolecular spacer system, which (1) can be immobilized on nearly all solid surfaces and (2) chemically modified to present a tailor-made functionality in contact with aqueous media either to avoid or inhibit surface fouling or to equip any implant surface with the necessary chemical functionality to enable cell adhesion and tissue integration. Ultrathin films based on tetraether lipids isolated from archaea Thermoplasma acidophilum were used as a special biomimetic immobilization matrix on the surface of commercial medical silicon elastomers. A complete performance control of the membrane analog coatings was realized in addition to biofunctionality tests, including the proof of cytotoxicity and hemocompatibility according to DIN EN ISO 10993. In order to make sure that the developed immobilization matrix including the grafted functional groups are biocompatible under in vivo-conditions, specific animal tests were carried out to examine the in vivo-performance. It can be concluded that the tetraether lipid based coating systems on silicone have shown no signs of cytotoxicity and a good hemocompatibility. Moreover, no mutagenic effects, no irritation effects, and no sensitization effects could be demonstrated. After an implantation period of 28 days, no irregularities were found.


Assuntos
Materiais Biomiméticos/síntese química , Materiais Revestidos Biocompatíveis/síntese química , Lipídeos/isolamento & purificação , Membranas/metabolismo , Thermoplasma/química , Animais , Materiais Biomiméticos/química , Materiais Biomiméticos/toxicidade , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/toxicidade , Hemólise , Humanos , Metabolismo dos Lipídeos , Membranas/química , Camundongos , Próteses e Implantes/efeitos adversos , Coelhos , Silício , Propriedades de Superfície
16.
Acta Biomater ; 23: 354-363, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26073090

RESUMO

Magnesium (Mg) is a promising biomaterial for degradable implant applications that has been extensively studied in vitro and in vivo in recent years. In this study, we developed a procedure that allows an optimized and uniform in vitro assessment of the cytocompatibility of Mg-based materials while respecting the standard protocol DIN EN ISO 10993-5:2009. The mouse fibroblast line L-929 was chosen as the preferred assay cell line and MEM supplemented with 10% FCS, penicillin/streptomycin and 4mM l-glutamine as the favored assay medium. The procedure consists of (1) an indirect assessment of effects of soluble Mg corrosion products in material extracts and (2) a direct assessment of the surface compatibility in terms of cell attachment and cytotoxicity originating from active corrosion processes. The indirect assessment allows the quantification of cell-proliferation (BrdU-assay), viability (XTT-assay) as well as cytotoxicity (LDH-assay) of the mouse fibroblasts incubated with material extracts. Direct assessment visualizes cells attached to the test materials by means of live-dead staining. The colorimetric assays and the visual evaluation complement each other and the combination of both provides an optimized and simple procedure for assessing the cytocompatibility of Mg-based biomaterials in vitro.


Assuntos
Algoritmos , Materiais Biocompatíveis/toxicidade , Fibroblastos/efeitos dos fármacos , Magnésio/toxicidade , Teste de Materiais/normas , Testes de Toxicidade/normas , Animais , Bioensaio/métodos , Bioensaio/normas , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Fibroblastos/patologia , Guias como Assunto , Técnicas In Vitro , Internacionalidade , Teste de Materiais/métodos , Camundongos , Testes de Toxicidade/métodos
17.
Eur J Hum Genet ; 23(6): 870-3, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25293717

RESUMO

Neurofibromatosis type 1 (NF1) (MIM#162200) is a relatively frequent genetic condition that predisposes to tumor formation. The main types of tumors occurring in NF1 patients are cutaneous and subcutaneous neurofibromas, plexiform neurofibromas, optic pathway gliomas, and malignant peripheral nerve sheath tumors. To search for somatic mutations in cutaneous (dermal) neurofibromas, whole-exome sequencing (WES) was performed on seven spatially separated tumors and two reference tissues (blood and unaffected skin) from a single NF1 patient. Validation of WES findings was done using routine Sanger sequencing or Sequenom IPlex SNP genotyping. Exome sequencing confirmed the existence of a known familial splice-site mutation NM_000267.3:c.3113+1G>A in exon 23 of NF1 gene (HGMD ID CS951480) in blood, unaffected skin, and all tumor samples. In five out of seven analyzed tumors, we additionally detected second-hit mutations in the NF1 gene. Four of them were novel and one was previously observed. Each mutation was distinct, demonstrating the independent origin of each tumor. Only in two of seven tumors we detected an additional somatic mutation that was not associated with NF1. Our study demonstrated that somatic mutations of NF1 are likely the main drivers of cutaneous tumor formation. The study provides evidence for the rareness of single base pair level alterations in the exomes of benign NF1 cutaneous tumors.


Assuntos
Mutação , Neurofibromatose 1/genética , Neurofibromina 1/genética , Neoplasias Cutâneas/genética , Evolução Clonal , Exoma , Feminino , Humanos , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único
18.
Oecologia ; 58(2): 215-219, 1983 May.
Artigo em Inglês | MEDLINE | ID: mdl-28310580

RESUMO

Fluorescent probes have been applied to study by epifluorescence microscopy interactions between species in an Anabaena flos-aquae association, derived from a freshwater community. Glycoconjugates (macromolecules containing carbohydrate residues) have been shown to play a vital role in recognition processes and in formation of attachment sites between cells. By use of a group of proteins (lectins) with specific affinities to certain sugar residues we were able to clucidate specific patterns expressed at cellular surfaces, thereby indicating the physiological state of a cell. Low molecular weight fluorochromes, like the fluorescent brightener calcofluor white have been shown to be extremely useful tools for visualizing structural entities (and species) which otherwise escape notice by microscopy. We have demonstrated that the decline of the bloom of Anabaena flos-aquae was caused or at least accelerated by action of a fungus (chytrid). We also proved that the shell (lorica) of a choanoflagellate most likely is built from chitin.

19.
Angew Chem Int Ed Engl ; 40(13): 2468-2471, 2001 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-29712279

RESUMO

By comparison of experimental and theoretical CD curves the absolute configurations of chromatographically baseline-separated enantiomers of new trefoil molecular knots could be determined. From the results of syntheses with differently substituted starting materials, conclusions can be drawn about the knot-formation mechanism.

20.
PLoS One ; 9(5): e96280, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24840482

RESUMO

AIMS: Long-term urodynamics are required because bladder-emptying disorders are often not clearly revealed by conventional urodynamics. Patients with severe clinical overactive bladder symptoms, for instance, often show normal results. This may be due to the short evaluation time and psychological factors that complicate conventional urodynamics. This study aimed to develop an ambulatory three-component urodynamic measurement system that is easy to operate, registers urodynamic parameters for several days, and has no negative impact on the patient. METHODS: We developed an intravesical capsule combined with a hand-held device to register voiding desire and micturition, and an alarm pad device that detects urine loss. Recently, the intravesical capsule and its proven function were detailed in the literature. Here, we present detailed in vitro results using a female bladder model. The flexible capsule was C-shaped to minimize the risk of expulsion from the bladder during micturition. Results of biocompatibility evaluation of the intravesical capsule, which is called Wille Capsule (WiCa) are described. RESULTS: The WiCa with an oval nose and a maximum outer diameter of 5.5 mm was easily inserted through a 25-French cystoscope. Removing the WiCa by grasping the nose using the female model with bladder was easily conducted. Expulsion of the WiCa during voiding was avoided through a novel C-shaped device design. Based on in vitro cytotoxicity studies, the capsule is a promising and safe device. CONCLUSION: Our novel system is an innovative minimally-invasive tool for accurate long-term urodynamic measurement, and does not require inserting a transurethral catheter.


Assuntos
Assistência Ambulatorial , Bexiga Urinária/fisiopatologia , Urodinâmica/fisiologia , Desenho de Equipamento , Feminino , Humanos , Bexiga Urinária Hiperativa/fisiopatologia , Micção/fisiologia
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