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1.
J Dairy Sci ; 106(6): 3961-3974, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37105872

RESUMEN

Accurate measurements of concentration and ruminal degradability of corn silage starch is necessary for formulation of diets that meet the energy requirements of dairy cows. Five corn silage hybrids ensiled for 0 (unfermented), 30, 60, 120, and 150 d were used to determine the effects of ensiling time on starch degradability of corn silage. In addition, the effects of grind size of silage samples on 7-h in vitro starch degradability and the relationship between in vitro, in situ and near-infrared reflectance spectroscopy (NIRS) starch degradability were studied. In situ disappearance of corn silage starch increased from 0 to 150 d of ensiling, primarily as a result of an increase in the washout or rapidly degraded fraction of starch, particularly during the first 60 d of ensiling. When analyzed in vitro and by NIRS, ensiling time increased corn silage starch degradability either linearly or to a greater extent during the first 2 mo of ensiling. Differences in in situ starch disappearance among corn silage hybrids were apparent during the first 2 mo of ensiling but were attenuated as silages aged. No differences among hybrids were detected using a 7-h in vitro starch digestibility approach. Results from the in vitro subexperiment indicate that 7-h in vitro starch degradability was increased by reducing grind size of corn silage from 4 to 1 mm, regardless of ensiling duration. Fine grinding corn silages samples (i.e., 1-mm sieve) allowed distinguishing low- from medium- and high-starch degradability rated hybrids. Correlations among in situ, in vitro and NIRS measurements for starch degradability were medium to high (r ≥0.57); however, agreement among methods was low (concordance correlation coefficient ≤0.15). In conclusion, ensiling time linearly increased degradation rate of corn silage resulting in greater in situ starch disappearance after 150 d of ensiling. Reductions in grind size from 4 to 1 mm resulted in greater in vitro starch degradability, regardless of ensiling duration. Strong correlation but low agreement between starch degradability methods suggest that absolute estimations of corn silage starch degradability will vary, but all methods can be used to assess the effect of ensiling time on starch degradability.


Asunto(s)
Ensilaje , Zea mays , Bovinos , Femenino , Animales , Ensilaje/análisis , Zea mays/metabolismo , Rumen/metabolismo , Digestión , Almidón/metabolismo , Fermentación , Fibras de la Dieta/metabolismo
2.
Tech Coloproctol ; 27(5): 407-418, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36326939

RESUMEN

BACKGROUND: A recent meta-analysis showed that obesity increased the conversion rate and postoperative morbidity of rectal cancer surgery, but did not influence pathological results. However, this meta-analysis included patients with cancer of the upper rectum and had many biases. The aim of the present retrospective study was to investigate the impact of obesity, defined as a body mass index (BMI) ≥ 30 kg/m2, on postoperative morbidity and short- and long-term oncologic outcomes of total mesorectal excision for mid and low rectal cancer in consecutive patients. METHODS: This study included all eligible patients who were operated on for mid and lower rectal cancer between 1999 and 2018 in our hospital. We compared 90-day postoperative morbidity and mortality, and short- and long-term oncologic outcomes between obese and non-obese patients. RESULTS: Three hundred and ninety patients [280 males, mean age 65.7 ± 11.3 years, 59 obese individuals (15.1%)] were included. There was no difference in the 90-day mortality rate between obese and non-obese groups (p = 0.068). There was a difference in the overall 90-day morbidity rate between the obese and non-obese groups that disappeared after propensity score matching of the patients. There was no difference in short-term oncological parameters, with a median follow-up of 43 (20-84) months, and there were no significant differences in disease-free and overall survival between obese and non-obese patients (p = 0.42 and p = 0.11, respectively). CONCLUSIONS: Obesity does not affect the 90-day morbidity rate, or short- and long-term oncologic results in patients operated on for mid and lower rectal cancer.


Asunto(s)
Laparoscopía , Neoplasias del Recto , Masculino , Humanos , Persona de Mediana Edad , Anciano , Estudios Retrospectivos , Laparoscopía/métodos , Neoplasias del Recto/complicaciones , Neoplasias del Recto/cirugía , Recto/cirugía , Obesidad/complicaciones , Obesidad/cirugía , Resultado del Tratamiento , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/cirugía
3.
J Dairy Sci ; 104(9): 9827-9841, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34253370

RESUMEN

This study investigated the effects of an amylase-enabled corn silage on lactational performance, enteric CH4 emission, and rumen fermentation of lactating dairy cows. Following a 2-wk covariate period, 48 Holstein cows were blocked based on parity, days in milk, milk yield (MY), and CH4 emission. Cows were randomly assigned to 1 of 2 treatments in an 8-wk randomized complete block design experiment: (1) control corn silage (CON) from an isogenic corn without α-amylase trait and (2) Enogen hybrid corn (Syngenta Seeds LLC) harvested as silage (ECS) containing a bacterial transgene expressing α-amylase (i.e., amylase-enabled) in the endosperm of the grain. The ECS and CON silages were included at 40% of the dietary dry matter (DM) and contained, on average, 43.3 and 41.8% DM and (% DM) 36.7 and 37.5% neutral detergent fiber, and 36.1 and 33.1% starch, respectively. Rumen samples were collected from a subset of 10 cows using the ororuminal sampling technique on wk 3 of the experimental period. Enteric CH4 emission was measured using the GreenFeed system (C-Lock Inc.). Dry matter intake (DMI) was similar between treatments. Compared with CON, MY (38.8 vs. 40.8 kg/d), feed efficiency (1.47 vs. 1.55 kg of MY/kg of DMI), and milk true protein (1.20 vs. 1.25 kg/d) and lactose yields (1.89 vs. 2.00 kg/d) were increased, whereas milk urea nitrogen (14.0 vs. 12.7 mg/dL) was decreased, with the ECS diet. No effect of treatment on energy-corrected MY (ECM) was observed, but a trend was detected for increased ECM feed efficiency (1.45 vs. 1.50 kg of ECM/kg of DMI) for cows fed ECS compared with CON-fed cows. Daily CH4 emission was not affected by treatment, but emission intensity was decreased with the ECS diet (11.1 vs. 10.3 g/kg of milk, CON and ECS, respectively); CH4 emission intensity on ECM basis was not different between treatments. Rumen fermentation, apart from a reduced molar proportion of butyrate in ECS-fed cows, was not affected by treatment. Apparent total-tract digestibility of nutrients and urinary and fecal nitrogen excretions, apart from a trend for increased DM digestibility by ECS-fed cows, were not affected by treatment. Overall, ECS inclusion at 40% of dietary DM increased milk, milk protein, and lactose yields and feed efficiency, and tended to increase ECM feed efficiency but had no effect on ECM yield in dairy cows. The increased MY with ECS led to a decrease in enteric CH4 emission intensity, compared with the control silage.


Asunto(s)
Rumen , Ensilaje , Amilasas/metabolismo , Animales , Bovinos , Dieta/veterinaria , Digestión , Femenino , Fermentación , Lactancia , Metano/metabolismo , Embarazo , Rumen/metabolismo , Ensilaje/análisis , Zea mays
4.
J Dairy Sci ; 103(3): 2333-2346, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31882208

RESUMEN

Accurate analysis of degradability of silage neutral detergent fiber (NDF) is important for diet formulation and to predict lactational performance of dairy cows. In this study, 5 corn silage hybrids ensiled for 0 (unfermented), 30, 60, 120, and 150 d were used to determine the effects of ensiling time on silage neutral detergent fiber degradability (NDFD) and to assess the relationships between near-infrared reflectance spectroscopy (NIR) NDF-related analyses and in situ NDFD variables. In addition, the relationships between dietary concentration of indigestible NDF, 288-h incubation (iNDF288), or undegraded NDF, 240-h incubation (uNDF240), and in vivo total-tract apparent organic matter and NDF digestibility were studied in total mixed ration samples from 16 experiments with lactating dairy cows. Ensiling time had no effect on silage NDF concentration; however, the ratio of acid detergent fiber ÷ NDF increased, and estimated hemicellulose concentration decreased quadratically with ensiling time. Also, concentration of NDF-bound protein decreased, and that of lignin increased linearly with ensiling time. These changes in silage fiber composition resulted in a linear decrease in in situ effective degradability of silage NDF with increasing ensiling time. The indigestible fraction of NDF and concentration of structural carbohydrates were not affected by ensiling time. Correlations of in situ NDFD variables with laboratory NIR NDFD analyses were weak to moderate. The relationship of corn silage uNDF240 with lignin concentration or 30-h NDFD (all NIR analyses) was remarkably good (R2 = 0.73 and 0.88, respectively). The relationship between in situ iNDF288 concentration (but not uNDF240) and in vivo total-tract apparent digestibility of dietary organic matter and NDF was good (R2 = 0.72 and 0.80, respectively). In conclusion, in situ degradability of silage NDF linearly decreased from 0 to 150 d ensiling time, primarily caused by a decrease in concentrations of hemicellulose and NDF-bound protein. In situ NDF degradability measurements and common laboratory NIR NDF-related analyses were generally poorly correlated. We found a good relationship between in vivo NDF digestibility and dietary concentration of iNDF288 determined in situ, but the relationship with uNDF240 was poor.


Asunto(s)
Bovinos/fisiología , Fibras de la Dieta/análisis , Ensilaje/análisis , Zea mays , Animales , Detergentes , Dieta/veterinaria , Fibras de la Dieta/metabolismo , Digestión , Femenino , Lactancia , Lignina/análisis , Lignina/metabolismo , Rumen/metabolismo , Factores de Tiempo
5.
Rev Sci Instrum ; 89(9): 095001, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30278737

RESUMEN

Here we describe the first neutral wind sensor developed specifically for use on resource limited nano-satellite platforms. The instrument is a next generation redesign of the ram wind sensor flown on the Communications/Navigation Outage Forecasting System satellite for measurements of neutral velocity, temperature, and composition. Results of subsystem tests in vacuum conditions show low-power operation, promising design, and good resolution of measured parameters over the operational pressure and energy ranges expected in the low Earth orbit environment.

6.
Br J Anaesth ; 121(3): 656-661, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30115264

RESUMEN

BACKGROUND: Preoperative fasting is a major cause of perioperative discomfort in paediatric anaesthesia and leads to postoperative insulin resistance, thus potentially enhancing the inflammatory response to surgery. Addressing these problems by preoperative carbohydrate intake has not been a well-defined approach in children. METHODS: We randomised 120 children scheduled for gastroscopy under general anaesthesia to either a control group of standard preoperative fasting or a study group receiving a carbohydrate beverage (PreOp™; Nutricia, Erlangen, Germany). Their stomach contents were aspirated endoscopically, and the volume and pH measured. Perioperative discomfort was evaluated using, among other parameters, an observational pain scale in ≤4-yr-olds and a VAS in >4-yr-olds. The investigators doing the endoscopies and outcome evaluations were blinded to the study group allocation. RESULTS: Compared with fasting, carbohydrate loading was associated with significantly less gastric content (P=0.01), fewer patients experiencing postoperative nausea (P=0.028), with no significant difference in postoperative vomiting. High preoperative VAS scores (>5) were recorded for only one child in the carbohydrate group vs five children in the fasting group. Bowel cleansing for simultaneous colonoscopies (n=61) made no difference to any of the intergroup findings. CONCLUSIONS: Preoperative carbohydrates can reduce nausea and gastric content, the latter being a surrogate parameter for the risk and severity of gastric aspiration into the lungs during anaesthesia. Our study adds knowledge for preoperative fasting guidelines in paediatric anaesthesia. CLINICAL TRIAL REGISTRATION: DRKS00005020.


Asunto(s)
Anestesia General/métodos , Dieta de Carga de Carbohidratos , Ayuno , Cuidados Preoperatorios/métodos , Adolescente , Niño , Preescolar , Colonoscopía , Femenino , Vaciamiento Gástrico , Contenido Digestivo , Gastroscopía/métodos , Humanos , Masculino , Dimensión del Dolor/métodos , Neumonía por Aspiración/prevención & control , Náusea y Vómito Posoperatorios/prevención & control , Método Simple Ciego
7.
J Dairy Sci ; 101(6): 5006-5019, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29525315

RESUMEN

Brown midrib brachytic dwarf pearl millet (Pennisetum glaucum) forage harvested at the flag leaf visible stage and subsequently ensiled was investigated as a partial replacement of corn silage in the diet of high-producing dairy cows. Seventeen lactating Holstein cows were fed 2 diets in a crossover design experiment with 2 periods of 28 d each. Both diets had forage:concentrate ratios of 60:40. The control diet (CSD) was based on corn silage and alfalfa haylage, and in the treatment diet, 20% of the corn silage dry matter (corresponding to 10% of the dietary dry matter) was replaced with pearl millet silage (PMD). The effects of partial substitution of corn silage with pearl millet silage on dry matter intake, milk yield, milk components, fatty acid profile, apparent total-tract digestibility of nutrients, N utilization, and enteric methane emissions were analyzed. The pearl millet silage was higher in crude protein and neutral detergent fiber and lower in lignin and starch than the corn silage. Diet did not affect dry matter intake or energy-corrected milk yield, which averaged 46.7 ± 1.92 kg/d. The PMD treatment tended to increase milk fat concentration, had no effect on milk fat yield, and increased milk urea N. Concentrations and yields of milk protein and lactose were not affected by diet. Apparent total-tract digestibility of dry matter decreased from 66.5% in CSD to 64.5% in PMD. Similarly, organic matter and crude protein digestibility was decreased by PMD, whereas neutral- and acid-detergent fiber digestibility was increased. Total milk trans fatty acid concentration was decreased by PMD, with a particular decrease in trans-10 18:1. Urinary urea and fecal N excretion increased with PMD compared with CSD. Milk N efficiency decreased with PMD. Carbon dioxide emission was not different between the diets, but PMD increased enteric methane emission from 396 to 454 g/d and increased methane yield and intensity. Substituting corn silage with brown midrib dwarf pearl millet silage at 10% of the diet dry matter supported high milk production in dairy cows. When planning on farm forage production strategies, brown midrib dwarf pearl millet should be considered as a viable fiber source.


Asunto(s)
Alimentación Animal/análisis , Bovinos/fisiología , Pennisetum/metabolismo , Ensilaje/análisis , Animales , Bovinos/crecimiento & desarrollo , Dieta/veterinaria , Fibras de la Dieta/análisis , Fibras de la Dieta/metabolismo , Digestión , Granjas , Ácidos Grasos/química , Ácidos Grasos/metabolismo , Femenino , Lactancia , Medicago sativa/química , Medicago sativa/metabolismo , Metano/biosíntesis , Leche/química , Leche/metabolismo , Pennisetum/química , Rumen/metabolismo , Ensilaje/envenenamiento , Zea mays/química , Zea mays/metabolismo
8.
J Phys Condens Matter ; 30(6): 065401, 2018 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-29337696

RESUMEN

Monazite-type BiPO4, LaPO4, CePO4, and PrPO4 have been studied under high pressure by ab initio simulations and Raman spectroscopy measurements in the pressure range of stability of the monazite structure. A good agreement between experimental and theoretical Raman-active mode frequencies and pressure coefficients has been found which has allowed us to discuss the nature of the Raman-active modes. Besides, calculations have provided us with information on how the crystal structure is modified by pressure. This information has allowed us to determine the equation of state and the isothermal compressibility tensor of the four studied compounds. In addition, the information obtained on the polyhedral compressibility has been used to explain the anisotropic axial compressibility and the bulk compressibility of monazite phosphates. Finally, we have carried out a systematic discussion on the high-pressure behavior of the four studied phosphates in comparison to results of previous studies.

9.
J Dairy Sci ; 101(1): 222-232, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29103704

RESUMEN

Corn silage and high-moisture corn grain are commonly recognized as risk factors for biohydrogenation-induced milk fat depression and may be due to the high concentration of linoleic acid (C18:2) in corn. Corn silage and corn grain have a low concentration of fatty acids (FA), but due to their high inclusion rate in diets they contribute substantially to unsaturated FA intake. The first objective of this study was to characterize the contribution of individual plant parts to total FA in whole-plant chopped corn. The second objective was to characterize the variation in FA profile in commercial silage and grain hybrids and evaluate the relationship between FA profile and other nutrients. To determine the location of FA in the corn plant, 4 stalks from 4 different commercial hybrids were separated into stalk, husk and shank, leaves, cob, and kernels. On a dry matter basis, 80.5% of total FA were in the kernels, 11.8% in the leaves, 5.1% in the stalk, 1.7% in the cob, and 1.0% in the husk and shank. More than 96% of the oleic acid (C18:1) and 92.5% of the C18:2 was in the kernels, whereas 71.0% of the linolenic acid (C18:3) was in the leaves. Next, the FA composition of fresh whole-plant chopped corn from 124 silage hybrids and grain from 72 grain hybrids was determined over 2 yr from test plots in Pennsylvania. Last, to extend the characterization, FA composition of whole-plant corn silage from 45 hybrids grown in test plots in South Dakota were characterized. In the fresh whole-plant chopped corn from PA test plots, C18:2 as a percentage of total FA averaged from 48.7% in 2013 (percentiles: 10th = 45.2, 90th = 52.2) and 48.0% in 2014 (percentiles: 10th = 44.1, 90th = 49.4). Concentration of C18:2 in corn grain averaged 57.5% in the 2013 (percentiles: 10th = 53.4, 90th = 60.8) and 56.1% in 2014 (percentiles: 10th = 53.5, 90th = 59.4). In the corn silage from South Dakota, the concentration of C18:2 as percentage of total FA averaged 45.4% (percentiles: 10th = 39.4, 90th = 50.2) and C18:2 concentration as a percent of dry matter averaged 1.1% (percentiles: 10th = 0.76, 90th = 1.41). An increase in the concentration of C18:2 was associated with a decrease in C18:3 in fresh whole-plant chopped corn and with a decrease in C18:1 in corn grain. Total FA and C18:2 (as a percentage of dry matter) were positively correlated with starch and negatively correlated with neutral detergent fiber in both fresh whole-plant chopped corn and corn silage samples, whereas no correlation with these traits was observed for C18:2 as a percentage of total FA. In conclusion, FA concentration and profile of corn silage reflects to a great extent the FA composition of kernels and the proportion of grain in the silage. The variation in C18:2 across hybrids provides the opportunity to develop selection programs to decrease C18:2 in corn silage and grain. Selection based on C18:2 concentration as a percent of total FA is preferred as this trait did not correlate with other nutritional properties.


Asunto(s)
Grano Comestible/genética , Ácido Linoleico/química , Ensilaje/análisis , Zea mays , Carbohidratos/química , Fibras de la Dieta/análisis , Ácidos Grasos , Hibridación Genética , Valor Nutritivo
10.
J Dairy Sci ; 100(8): 6151-6163, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28601456

RESUMEN

The objective of this experiment was to partially replace corn silage with 2 alternative forages, wheat (Triticum aestivum) or triticale (X Triticosecale) silages at 10% of the diet dry matter (DM), and investigate the effects on dairy cow productivity, nutrient utilization, enteric CH4 emissions, and farm income over feed costs. Wheat and triticale were planted in the fall as cover crops and harvested in the spring at the boot stage. Neutral- and acid-detergent fiber and lignin concentrations were higher in the wheat and triticale silages compared with corn silage. The forages had similar ruminal in situ effective degradability of DM. Both alternative forages had 1% starch or less compared with the approximately 35% starch in corn silage. Diets with the alternative forages were fed in a replicated 3 × 3 Latin square design experiment with three 28-d periods and 12 Holstein cows. The control diet contained 44% (DM basis) corn silage. In the other 2 diets, wheat or triticale silages were included at 10% of dietary DM, replacing corn silage. Dry matter intake was not affected by diet, but both wheat and triticale silage decreased yield of milk (41.4 and 41.2 vs. 42.7 ± 5.18 kg/d) and milk components, compared with corn silage. Milk fat from cows fed the alternative forage diets contained higher concentrations of 4:0, 6:0, and 18:0 and tended to have lower concentrations of total trans fatty acids. Apparent total-tract digestibility of DM and organic matter was decreased in the wheat silage diet, and digestibility of neutral-and acid-detergent fiber was increased in the triticale silage diet. The wheat and triticale silage diets resulted in higher excretion of urinary urea, higher milk urea N, and lower milk N efficiency compared with the corn silage diet. Enteric CH4 emission per kilogram of energy-corrected milk was highest in the triticale silage diet, whereas CO2 emission was decreased by both wheat and triticale silage. This study showed that, at milk production of around 42 kg/d, wheat silage and triticale silage can partially replace corn silage DM and not affect DM intake, but milk yield may decrease slightly. For dairy farms in need of more forage, triticale or wheat double cropped with corn silage may be an appropriate cropping strategy.


Asunto(s)
Fenómenos Fisiológicos Nutricionales de los Animales , Bovinos/fisiología , Dieta/veterinaria , Ensilaje , Contaminantes Atmosféricos/análisis , Animales , Fibras de la Dieta , Digestión , Femenino , Lactancia/fisiología , Leche/metabolismo , Rumen/metabolismo , Ensilaje/análisis , Triticale , Triticum , Zea mays
11.
J Dairy Sci ; 100(7): 5250-5265, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28527803

RESUMEN

Double cropping and increasing crop diversity could improve dairy farm economic and environmental sustainability. In this experiment, corn silage was partially replaced with 2 alternative forages, brown midrib-6 brachytic dwarf forage sorghum (Sorghum bicolor) or fall-grown oat (Avena sativa) silage, in the diet of lactating dairy cows. We investigated the effect on dry matter (DM) intake, milk yield (MY), milk components and fatty acid profile, apparent total-tract nutrient digestibility, N utilization, enteric methane emissions, and income over feed cost. We analyzed the in situ DM and neutral detergent fiber disappearance of the alternative forages versus corn silage and alfalfa haylage. Sorghum was grown in the summer and harvested in the milk stage. Oats were grown in the fall and harvested in the boot stage. Compared with corn silage, neutral detergent fiber and acid detergent fiber concentrations were higher in the alternative forages. Lignin content was highest for sorghum silage and similar for corn silage and oat silage. The alternative forages had less than 1% starch compared with the approximately 35% starch in the corn silage. Ruminal in situ DM effective degradability was similar, although statistically different, for corn silage and oat silage, but lower for sorghum silage. Diets with the alternative forages were fed in a replicated 3 × 3 Latin square design experiment with three 28-d periods and 12 Holstein cows. The control diet contained 44% (DM basis) corn silage. In the other 2 diets, sorghum or oat silages were included at 10% of dietary DM, replacing corn silage. Sorghum silage inclusion decreased DM intake, MY, and milk protein content but increased milk fat and maintained energy-corrected MY similar to the control. Oat silage had no effect on DM intake, MY, or milk components compared to the control. The oat silage diet increased apparent total-tract digestibility of dietary nutrients, except starch, whereas the sorghum diet slightly decreased DM, organic matter, crude protein, and starch digestibility. Cows consuming the oat silage diet had higher milk urea N and urinary urea N concentrations. Milk N efficiency was decreased by the sorghum diet. Diet did not affect enteric methane or carbon dioxide emissions. This study shows that oat silage can partially replace corn silage at 10% of the diet DM with no effect on MY. Brown midrib sorghum silage harvested at the milk stage with <1% starch may decrease DM intake and MY in dairy cows.


Asunto(s)
Avena , Productos Agrícolas , Lactancia , Leche/metabolismo , Ensilaje , Sorghum , Animales , Bovinos , Industria Lechera , Dieta , Fibras de la Dieta , Digestión , Granjas , Femenino , Medicago sativa , Zea mays
12.
Rev Sci Instrum ; 87(10): 105108, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27802694

RESUMEN

A new polarized neutron single crystal diffractometer POLI (Polarization Investigator) has been developed at the Maier-Leibnitz Zentrum, Garching, Germany. After reviewing existing devices, spherical neutron polarimetry has been implemented on POLI as a main experimental technique using a third-generation cryogenic polarization analysis device (Cryopad) built in cooperation between RWTH University and Institut Laue-Langevin. In this report we describe the realization and present the performance of the new Cryopad on POLI. Some improvements in the construction as well as details regarding calibrations of Cryopad and its practical use are discussed. The reliable operation of the new Cryopad on POLI is also demonstrated.

13.
J Nanopart Res ; 18: 159, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27594804

RESUMEN

Engineered nanomaterials significantly entered commerce at the beginning of the 21st century. Concerns about serious potential health effects of nanomaterials were widespread. Now, approximately 15 years later, it is worthwhile to take stock of research and efforts to protect nanomaterial workers from potential risks of adverse health effects. This article provides and examines timelines for major functional areas (toxicology, metrology, exposure assessment, engineering controls and personal protective equipment, risk assessment, risk management, medical surveillance, and epidemiology) to identify significant contributions to worker safety and health. The occupational safety and health field has responded effectively to identify gaps in knowledge and practice, but further research is warranted and is described. There is now a greater, if imperfect, understanding of the mechanisms underlying nanoparticle toxicology, hazards to workers, and appropriate controls for nanomaterials, but unified analytical standards and exposure characterization methods are still lacking. The development of control-banding and similar strategies has compensated for incomplete data on exposure and risk, but it is unknown how widely such approaches are being adopted. Although the importance of epidemiologic studies and medical surveillance is recognized, implementation has been slowed by logistical issues. Responsible development of nanotechnology requires protection of workers at all stages of the technological life cycle. In each of the functional areas assessed, progress has been made, but more is required.

14.
J Biotechnol ; 234: 90-98, 2016 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-27485811

RESUMEN

In situ Microscopy (ISM) is an optical non-invasive technique to monitor cells in bioprocesses in real-time. Pichia pastoris is one of the most promising protein expression systems. This yeast combines fast growth on simple media and important eukaryotic features such as glycosylation. In this work, the ISM technology was applied to Pichia pastoris cultivations for online monitoring of the cell concentration during cultivation. Different ISM settings were tested. The acquired images were analyzed with two image processing algorithms. In seven cultivations the cell concentration was monitored by the applied algorithms and offline samples were taken to determine optical density (OD) and dry cell mass (DCM). Cell concentrations up to 74g/L dry cell mass could be analyzed via the ISM. Depending on the algorithm and the ISM settings, an accuracy between 0.3 % and 12 % was achieved. The overall results show that for a robust measurement a combination of the two described algorithms is required.


Asunto(s)
Técnicas de Cultivo de Célula , Microscopía/métodos , Pichia/crecimiento & desarrollo , Algoritmos , Biomasa , Reactores Biológicos , Procesamiento de Imagen Asistido por Computador , Microscopía/instrumentación , Pichia/citología , Pichia/metabolismo
15.
Neuroscience ; 314: 160-9, 2016 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-26679600

RESUMEN

Experimental autoimmune encephalomyelitis (EAE) is a widely used animal model for the human disease multiple sclerosis (MS), a demyelinating and neurodegenerative pathology of the central nervous system. Both diseases share physiopathological and clinical characteristics, mainly associated with a neuroinflammatory process that leads to a set of motor, sensory, and cognitive symptoms. In MS, gray matter atrophy is related to the emergence of cognitive deficits and contributes to clinical progression. In particular, injury and dysfunction in certain areas of the frontal cortex (FrCx) have been related to the development of cognitive impairments with high incidence, like central fatigue and executive dysfunction. In the present work we show the presence of region-specific microglia and astrocyte activation in the FrCx, during the first hours of acute EAE onset. It is accompanied by the production of the pro-inflammatory cytokines IL-6 and TNF-α, in the absence of detectable leukocyte infiltration. These findings expand previous studies showing presynaptic neural dysfunction occurring at the FrCx and might contribute to the understanding of the mechanisms involved in the genesis and prevalence of common MS symptoms.


Asunto(s)
Astrocitos/fisiología , Encefalitis/metabolismo , Encefalomielitis Autoinmune Experimental/fisiopatología , Lóbulo Frontal/metabolismo , Lóbulo Frontal/fisiopatología , Microglía/fisiología , Animales , Modelos Animales de Enfermedad , Mediadores de Inflamación/metabolismo , Interleucina-6/metabolismo , Ratas , Ratas Wistar , Factor de Necrosis Tumoral alfa/metabolismo
16.
Lab Chip ; 15(18): 3749-59, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26235430

RESUMEN

Diagnosis of infectious diseases suffers from long turnaround times for gold standard culture-based identification of bacterial pathogens, therefore impeding timely specific antimicrobial treatment based on laboratory evidence. Rapid molecular diagnostics-based technologies enable detection of microorganisms within hours however cumbersome workflows and complex equipment still prevent their widespread use in the routine clinical microbiology setting. We developed a centrifugal-microfluidic "LabDisk" system for rapid and highly-sensitive pathogen detection on a point-of-care analyser. The unit-use LabDisk with pre-stored reagents features fully automated and integrated DNA extraction, consensus multiplex PCR pre-amplification and geometrically-multiplexed species-specific real-time PCR. Processing merely requires loading of the sample and DNA extraction reagents with minimal hands-on time of approximately 5 min. We demonstrate detection of as few as 3 colony-forming-units (cfu) of Staphylococcus warneri, 200 cfu of Streptococcus agalactiae, 5 cfu of Escherichia coli and 2 cfu of Haemophilus influenzae in a 200 µL serum sample. The turnaround time of the complete analysis from "sample-to-result" was 3 h and 45 min. The LabDisk consequently provides an easy-to-use molecular diagnostic platform for rapid and highly-sensitive detection of bacterial pathogens without requiring major hands-on time and complex laboratory instrumentation.


Asunto(s)
Bacterias , Técnicas de Tipificación Bacteriana , ADN Bacteriano , Dispositivos Laboratorio en un Chip , Reacción en Cadena de la Polimerasa Multiplex , Bacterias/clasificación , Bacterias/genética , Técnicas de Tipificación Bacteriana/instrumentación , Técnicas de Tipificación Bacteriana/métodos , Centrifugación/instrumentación , Centrifugación/métodos , ADN Bacteriano/química , ADN Bacteriano/genética , Reacción en Cadena de la Polimerasa Multiplex/instrumentación , Reacción en Cadena de la Polimerasa Multiplex/métodos
17.
Biosens Bioelectron ; 69: 301-6, 2015 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-25771302

RESUMEN

Single-cell analysis has developed into a key topic in cell biology with future applications in personalized medicine, tumor identification as well as tumor discovery (Editorial, 2013). Here we employ inkjet-like printing to isolate individual living single human B cells (Raji cell line) and load them directly into standard PCR tubes. Single cells are optically detected in the nozzle of the microfluidic piezoelectric dispenser chip to ensure printing of droplets with single cells only. The printing process has been characterized by using microbeads (10µm diameter) resulting in a single bead delivery in 27 out of 28 cases and relative positional precision of ±350µm at a printing distance of 6mm between nozzle and tube lid. Process-integrated optical imaging enabled to identify the printing failure as void droplet and to exclude it from downstream processing. PCR of truly single-cell DNA was performed without pre-amplification directly from single Raji cells with 33% success rate (N=197) and Cq values of 36.3±2.5. Additionally single cell whole genome amplification (WGA) was employed to pre-amplify the single-cell DNA by a factor of >1000. This facilitated subsequent PCR for the same gene yielding a success rate of 64% (N=33) which will allow more sophisticated downstream analysis like sequencing, electrophoresis or multiplexing.


Asunto(s)
Mapeo Cromosómico/instrumentación , Periféricos de Computador , ADN/genética , Dispositivos Laboratorio en un Chip , Linfoma/patología , Reacción en Cadena de la Polimerasa/instrumentación , Sustitutos Sanguíneos , Línea Celular Tumoral , Diseño de Equipo , Análisis de Falla de Equipo , Humanos , Técnicas de Amplificación de Ácido Nucleico/instrumentación , Robótica/instrumentación
18.
Neuroscience ; 277: 217-28, 2014 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-25020120

RESUMEN

Multiple sclerosis and its animal model, experimental autoimmune encephalomyelitis (EAE), are crucially dependent on the invasion of activated autoreactive lymphocytes and blood macrophages into the central nervous system (CNS). Proinflammatory mononuclear cells and activated local microglia mediate inflammation, demyelination and axonal damage at the target organ. Previously, we observed that the administration of a hybrid between the synapsin ABC domains and the B subunit of Escherichia coli heat labile-enterotoxin (LTBABC) to rats with EAE ameliorated disease by modulating the peripheral Th1 response to myelin basic protein (MBP). In the present study, we investigated the effect of LTBABC administration on proinflammatory cell frequency in the CNS of rats with EAE. Treatment with the hybrid in the inductive phase of EAE attenuated disease severity and diminished histological inflammatory infiltrates and demyelination in the spinal cord of rats with acute EAE. Lower frequencies of infiltrating and local macrophages as well as CD4+ T cells that produce the proinflammatory cytokines interferon-gamma (IFN-γ) and interleukin (IL)-17 were found at the target organ. Concomitantly, low levels of INF-γ and IL-17 and increased levels of IL-10 were measured in cultures of CNS infiltrating cells and spinal cord tissue. An increased frequency of CD4+CD25+Foxp3 cells was observed at the disease peak and at the beginning of the recovery stage. These results provide further evidence for the immunomodulatory properties of the fusion protein LTBABC in autoimmune demyelinating disease affecting the central nervous system.


Asunto(s)
Toxinas Bacterianas/administración & dosificación , Encefalomielitis Autoinmune Experimental/tratamiento farmacológico , Enterotoxinas/administración & dosificación , Proteínas de Escherichia coli/administración & dosificación , Fármacos Neuroprotectores/administración & dosificación , Médula Espinal/efectos de los fármacos , Sinapsinas/administración & dosificación , Animales , Toxinas Bacterianas/genética , Linfocitos T CD4-Positivos/efectos de los fármacos , Linfocitos T CD4-Positivos/fisiología , Bovinos , Células Cultivadas , Encefalomielitis Autoinmune Experimental/patología , Encefalomielitis Autoinmune Experimental/fisiopatología , Enterotoxinas/genética , Escherichia coli , Proteínas de Escherichia coli/genética , Femenino , Interferón gamma/metabolismo , Interleucina-10/metabolismo , Interleucina-17/metabolismo , Macrófagos/efectos de los fármacos , Macrófagos/fisiología , Masculino , Ratas Wistar , Proteínas Recombinantes de Fusión/administración & dosificación , Médula Espinal/patología , Médula Espinal/fisiopatología , Sinapsinas/genética
19.
Brain Res ; 1583: 141-58, 2014 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-24814646

RESUMEN

The neural processing of impulsive behavior is a central topic in various clinical and non-clinical contexts. To investigate neural and behavioral correlates of the empathic processing of complex social scenarios, especially considering ecological validity of the experimental procedure, we developed and investigated a video stimulus inventory. It includes realistic neutral, social-positive, and reactive-aggressive action scenarios. Short video-clips showing these social scenarios from a first-person perspective triggering different emotional states were presented to a non-clinical sample of 20 young adult male participants during fMRI measurements. Both affective interaction conditions (social-positive and reactive-aggressive) were contrasted against a neutral baseline condition and against each other. Behavioral evaluation data largely confirmed the validity of the emotion-inducing stimulus material. Reactive-aggressive and social-positive interaction scenarios produced widely overlapping fMRI activation patterns in hetero-modal association cortices, but also in subcortical regions, such as the peri-aqueductal gray. Reactive-aggressive compared to social-positive scenarios yielded a more anterior distribution of activations in pre-motor and inferior frontal brain regions associated to motor-preparation and inhibitory control processing as well as in the insula associated to pain- and/or aversion-processing. We argue that there are both principally common neural networks recruited for the processing of reactive-aggressive and social-positive scenarios, but also exclusive network parts in particular involved depending on individual socialization.


Asunto(s)
Encéfalo/fisiología , Empatía/fisiología , Relaciones Interpersonales , Percepción Social , Adulto , Agresión/fisiología , Mapeo Encefálico , Humanos , Imagen por Resonancia Magnética , Masculino , Autoimagen , Grabación en Video , Violencia , Adulto Joven
20.
J Cardiovasc Surg (Torino) ; 55(6): 849-56, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24343370

RESUMEN

AIM: Cardiopulmonary bypass (CPB), utilized in on-pump coronary artery bypass graft procedures (CABG) induces generalized immune suppression, release of heat shock proteins (HSP), inflammatory markers and apoptosis-specific proteins. We hypothesized that continued mechanical ventilation during cardiopulmonary bypass attenuates immune response and HSP liberation. METHODS: Thirty patients undergoing conventional coronary artery bypass graft (CABG) operation were randomized into a ventilated on CPB (VG; N.=15) and a non-ventilated CPB group (NVG; N.=15). Blood samples were drawn at the beginning and end of surgery, as well as on the five consecutive postoperative days (POD). Molecular markers were measured by ELISA. Data are given as mean ± (SD). Mann-Whitney-U-test was used for statistical analysis. RESULTS: Serum concentrations of HSP70 were significantly lower in VG compared to NVG on POD-1 (VG: 1629±608 vs. NVG: 5203±2128.6 pg/mL, P<0.001). HSP27 and HSP60 depicted a minor increase in both study groups at the end of surgery without any intergroup differences (HSP27: VG 6207.9±1252.5 vs. NVG 7424.1±2632.5; HSP60: VG 1046.2±478.8 vs. NVG 1223.5±510.1). IL-8 and CK-18 M30 evidenced the highest serum concentrations at the end of surgery (IL-8: VG 119.5±77.9 vs. NVG 148.0±184.55; CK-18 M30: VG 62.1±39.2 vs. NVG 67.5±33.9) with no differences between groups. Decreased ICAM-1 serum concentrations were detected postoperatively, however ICAM-1 concentrations on POD-1 to POD-5 showed slightly elevated concentrations in both study groups with no intergroup differences. CONCLUSION: Significantly less HSP70 was detectable in patients receiving uninterrupted mechanical lung ventilation on CPB, indicating either different inflammatory response, cellular stress or cell damage between the ventilated and non-ventilated group. These data suggest that continued mechanical ventilation has a modulatory effect on the immune response in patients after CABG surgery.


Asunto(s)
Puente Cardiopulmonar/efectos adversos , Puente de Arteria Coronaria/métodos , Proteínas de Choque Térmico/sangre , Inflamación/prevención & control , Respiración Artificial , Anciano , Anciano de 80 o más Años , Austria , Biomarcadores/sangre , Chaperonina 60/sangre , Femenino , Proteínas de Choque Térmico HSP27/sangre , Proteínas HSP70 de Choque Térmico/sangre , Humanos , Inflamación/sangre , Inflamación/etiología , Inflamación/inmunología , Mediadores de Inflamación/sangre , Masculino , Persona de Mediana Edad , Proteínas Mitocondriales/sangre , Chaperonas Moleculares , Factores de Tiempo , Resultado del Tratamiento
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