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101.
BackgroundNonesterified fatty acids (NEFA) play pathophysiological roles in metabolic syndrome and type 2 diabetes (T2D). In this study, we analyzed the fasting NEFA profiles of normoglycemic individuals at risk for T2D (women with a recent history of gestational diabetes (GDM)) in comparison to controls (women after a normoglycemic pregnancy). We also examined the associations of NEFA species with overweight/obesity, body fat distribution and insulin sensitivity.ResultsWomen after GDM had a lower molar percentage of total saturated fatty acids (SFA; 38.55% vs. 40.32%, p = 0.0002) than controls. At an explorative level of significance several NEFA species were associated with post-GDM status (with and without adjustment for body mass index (BMI) and HbA1c): The molar percentages of 14:0, 16:0, 18:0 and 18:4 were reduced, whereas those of 18:1, 18:2, 20:2, 24:4, monounsaturated fatty acids (MUFA), polyunsaturated fatty acids (PUFA) and total n-6 NEFA were increased. BMI and the amount of body fat correlated inversely with several SFA and MUFA and positively with various PUFA species over the whole study cohort (abs(ρ)≥0.3 for all). 14:0 was inversely and BMI-independently associated with abdominal visceral adiposity. We saw no correlations of NEFA species with insulin sensitivity and the total NEFA concentration was similar in the post-GDM and the control group.ConclusionIn conclusion, we found alterations in the fasting NEFA profile associated with a recent history of gestational diabetes, a risk marker for T2D. NEFA composition also varied with overweight/obesity and with body fat distribution, but not with insulin sensitivity.  相似文献   
102.

Introduction

To establish strategic priorities for the German national public health institute (RKI) and guide the institute''s mid-term strategic decisions, we prioritized infectious pathogens in accordance with their importance for national surveillance and epidemiological research.

Methods

We used the Delphi process with internal (RKI) and external experts and a metric-consensus approach to score pathogens according to ten three-tiered criteria. Additional experts were invited to weight each criterion, leading to the calculation of a median weight by which each score was multiplied. We ranked the pathogens according to the total weighted score and divided them into four priority groups.

Results

127 pathogens were scored. Eighty-six experts participated in the weighting; “Case fatality rate” was rated as the most important criterion. Twenty-six pathogens were ranked in the highest priority group; among those were pathogens with internationally recognised importance (e.g., Human Immunodeficiency Virus, Mycobacterium tuberculosis, Influenza virus, Hepatitis C virus, Neisseria meningitides), pathogens frequently causing large outbreaks (e.g., Campylobacter spp.), and nosocomial pathogens associated with antimicrobial resistance. Other pathogens in the highest priority group included Helicobacter pylori, Respiratory Syncytial Virus, Varicella zoster virus and Hantavirus.

Discussion

While several pathogens from the highest priority group already have a high profile in national and international health policy documents, high scores for other pathogens (e.g., Helicobacter pylori, Respiratory syncytial virus or Hantavirus) indicate a possible under-recognised importance within the current German public health framework. A process to strengthen respective surveillance systems and research has been started. The prioritization methodology has worked well; its modular structure makes it potentially useful for other settings.  相似文献   
103.
The use of mouse models in experimental research is of enormous importance for the study of hepatic physiology and pathophysiological disturbances. However, due to the small size of the mouse, technical details of the intraoperative monitoring procedure suitable for the mouse were rarely described. Previously we have reported a monitoring procedure to obtain hemodynamic parameters for rats. Now, we adapted the procedure to acquire systemic and hepatic hemodynamic parameters in mice, a species ten-fold smaller than rats. This film demonstrates the instrumentation of the animals as well as the data acquisition process needed to assess systemic and hepatic hemodynamics in mice. Vital parameters, including body temperature, respiratory rate and heart rate were recorded throughout the whole procedure. Systemic hemodynamic parameters consist of carotid artery pressure (CAP) and central venous pressure (CVP). Hepatic perfusion parameters include portal vein pressure (PVP), portal flow rate as well as the flow rate of the common hepatic artery (table 1). Instrumentation and data acquisition to record the normal values was completed within 1.5 h. Systemic and hepatic hemodynamic parameters remained within normal ranges during this procedure.This procedure is challenging but feasible. We have already applied this procedure to assess hepatic hemodynamics in normal mice as well as during 70% partial hepatectomy and in liver lobe clamping experiments. Mean PVP after resection (n= 20), was 11.41±2.94 cmH2O which was significantly higher (P<0.05) than before resection (6.87±2.39 cmH2O). The results of liver lobe clamping experiment indicated that this monitoring procedure is sensitive and suitable for detecting small changes in portal pressure and portal flow rate. In conclusion, this procedure is reliable in the hands of an experienced micro-surgeon but should be limited to experiments where mice are absolutely needed.  相似文献   
104.
105.
106.
To better understand the biology of tameness, i.e. tolerance of human presence and handling, we analyzed two lines of wild-derived rats (Rattus norvegicus) artificially selected for tameness and defensive aggression towards humans. In response to a gloved human hand, tame rats tolerated handling, whereas aggressive rats attacked. Cross-fostering showed that these behavioral differences are not caused by postnatal maternal effects. Tame rats were more active and explorative and exhibited fewer anxiety-related behaviors. They also had smaller adrenal glands, larger spleens and lower levels of serum corticosterone. Blood glucose levels were lower in tame rats, whereas the concentrations of nine amino acids were higher. In the brain, tame rats had lower serotonin and higher taurine levels than aggressive rats. Our findings reinforce the notion that tameness is correlated with differences in stress response and will facilitate future efforts to uncover the genetic basis for animal tameness.  相似文献   
107.

Key Message

Morphological plasticity helps plants to cope to environmental conditions. Allometric responses of the mangrove Avicennia germinans to increasing salinity are easily detectable when focusing on the top height trees.

Abstract

Several studies show that mangrove trees possess high species- and site-related trait allometry, suggesting large morphological plasticity that might be related to environmental conditions, but the causes of such variation are not clearly understood and systematic quantification is still missing. Both aspects are essential for a mechanistic understanding of the development and functioning of forests. We analyzed the role of salinity in the allometric relations of the mangrove Avicennia germinans, using: (1) the top height trees (trees with the largest diameters at breast height, which reflect forest properties at the maximum use of resources); (2) the slenderness coefficient (which indicates competition and environmental conditions); and (3) the crown to DBH ratio. These standard tools for forest scientists dealing with terrestrial forests are suitable to analyze the plastic responses of mangroves to salinity. First, the top height trees help to recognize structural forest properties that are not detectable when studying the whole stand. Second, we found that at salinities above 55 ‰, trees are less slender and develop wider crowns in relation to DBH than when growing at lower salinities. Our results suggest a significant change in allometric traits in relation to salinity, and reflect the plastic responses of tree traits in response to environmental variation. Understanding the plastic responses of plants to their environment can help to better model, predict, and manage forests in changing environments.  相似文献   
108.
Rideability, i.e. the ease and comfort with which a horse can be ridden, is considered to be one of the most important traits in riding horses. However, at present rideability is evaluated rather subjectively in breeding horse performance tests. The aim of the present study was to evaluate the role horse behaviour as well as degree and quality of rein tension might play in judges’ evaluation of horses’ rideability. Mares (n = 33) and stallions (n = 13) from two different mare- and one stallion-testing station were observed twice during their performance test dressage training. During these rides, rein tension was measured continuously, and frequency of behaviour patterns such as head-tossing, tail swishing, and snorting was recorded. Rein tension parameters showed reasonable repeatabilities within horse-rider pairs (e.g. mean rein tension: r2 = 0.61±0.11; variance of rein tension: r2 = 0.52±0.14). Regression analysis revealed that a larger proportion of variance in rideability scores could be explained by maximum (17%), mean (16%) and variance (15%) of rein tension compared to horses’ or riders’ behavioural parameters (tail-swishing: 5% and rider’s use of hands: 5%, respectively). According to mixed model analysis, rideability scores dropped (all P<0.05) with increasing mean, maximum and variability in rein tension (e.g. −0.37±0.14 scores per additional 10 Newton in mean tension). However, mean rein tension differed between testing stations (P<0.0001) ranging between 9.1±1.6 N in one station and 21.7±1.3 N in another station. These results indicate that quantity and consistency of rein tension is either directly or indirectly an important factor for judges to derive rideability scores. Given the importance of rein tension parameters to both rider comfort and horse welfare, potentially, measurements of rein tension along with behaviour observations assessing the quality of rein contact (e.g. distinguishing a light contact from attempts to evade contact) might be used to make the assessment of rideability more impartial.  相似文献   
109.
ABSTRACT: BACKGROUND: 5-hydroxytryptamine (5-HT) is one of the major neurotransmitters widely distributed in the CNS. Several 5-HT receptor subtypes have been identified in the spinal dorsal horn which act on both pre- and postsynaptic sites of excitatory and inhibitory neurons. However, the receptor subtypes and sites of actions as well as underlying mechanism are not clarified rigorously. Several electrophysiological studies have been performed to investigate the effects of 5-HT on excitatory transmission in substantia gelatinosa (SG) of the spinal cord. In the present study, to understand the effects of 5-HT on the inhibitory synaptic transmission and to identify receptor subtypes, the blind whole cell recordings were performed from SG neurons of rat spinal cord slices. RESULTS: Bath applied 5-HT (50 microM) increased the frequency but not amplitudes of spontaneous inhibitory postsynaptic currents (sIPSCs) in 58% of neurons, and both amplitude and frequency in 23 % of neurons. The frequencies of GABAergic and glycinergic mIPSCs were both enhanced. TTX (0.5 microM) had no effect on the increasing frequency, while the enhancement of amplitude of IPSCs was eliminated. Evoked-IPSCs (eIPSCs) induced by focal stimulation near the recording neurons in the presence of CNQX and APV were enhanced in both amplitude by 5-HT. In the presence of Ba2+ (1 mM), a potassium channel blocker, 5-HT had no effect on both frequency and amplitude. A 5-HT2Areceptor agonist, TCB-2 mimicked the 5-HT effect, and ketanserin, an antagonist of 5-HT2A receptor, inhibited the effect of 5-HT partially and TCB-2 almost completely. A 5-HT2C receptor agonist WAY 161503 mimicked the 5-HT effect and this effect was blocked by a 5-HT2C receptor antagonist, N-desmethylclozapine. The amplitude of sIPSCs were unaffected by both agonists. A 5-HT3 receptor agonist mCPBG enhanced both amplitude and frequency of sIPSCs. This effect was blocked by a 5-HT3 receptor antagonist ICS-205,930. The perfusion of 5-HT2B receptor agonist had no effect on sIPSCs. CONCLUSIONS: Our results demonstrated that 5-HT modulated the inhibitory transmission in SG by the activation of 5-HT2A and 5-HT2C receptors subtypes located predominantly at inhibitory interneuron terminals, and 5-HT3 receptors located at inhibitory interneuron terminals and soma-dendrites, consequently enhanced both frequency and amplitude.  相似文献   
110.
Gaining information about receptor profiles on cells, and subsequently finding the most efficient ligands for these signaling receptors, remain challenging tasks in stem cell and cancer research as well as drug development. We introduce a live-cell method with great potential in both screening for surface receptors and analysing binding forces of different ligands. The technique is based on the molecular force assay, a parallel-format, high-throughput experiment on a single-molecule level. On human red blood cells, we demonstrate the detection of the interaction of N-acetyl-α-D-galactosaminyl residues with the lectin helix pomatia agglutinine and of the CD47 receptor with its antibody. The measurements are performed under nearly physiological conditions and still provide a highly specific binding signal. Moreover, with a detailed comparative force analysis on two cell types with different morphology, we show that our method even allows the determination of a DNA force equivalent for the interaction of the CD47 receptor and its antibody.  相似文献   
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