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31.
When parental females (♀♀P = mothers) of the rotifer Notommata copeus are placed in light conditions inducing the appearance of mictic females in their offspring (F1), the age of the parents of these parental females significantly affects the ratio of mictic females in the F1 generation.

The preparental females (♀♀PP = grandmothers), the parental females and the F1 females are isolated in a medium changed at each generation and, in the second experimental series, changed daily: the preparental age effect implicates the transmission of substances on two generations.

This influence of the preparental age is rhythmic: the ratio of mictic females in F1 related to this age varies in a sinusoidal manner. This influence is endogenous: it persists, always in a sinusoidal form, when the medium in which each grandmother is placed is changed daily.

Furthermore, the net reproduction ratio, Ro, does not vary significantly with the preparental age during these experiments.  相似文献   
32.
A closed-loop system for the automated detection and control of epileptic seizures was created and tested in three Genetic Absence Epilepsy Rats from Strasbourg (GAERS) rats. In this preliminary study, a set of four EEG features were used to detect seizures and three different electrical stimulation strategies (standard (130 Hz), very high (500 Hz) and ultra high (1000 Hz)) were delivered to terminate seizures. Seizure durations were significantly shorter with all three stimulation strategies when compared to non-stimulated (control) seizures. We used mean seizure duration of epileptiform discharges persisting beyond the end of electrical stimulation as a measure of stimulus efficacy. When compared to the duration of seizures stimulated in the standard approach (7.0 s ± 10.1), both very high and ultra high frequency stimulation strategies were more effective at shortening seizure durations (1.3 ± 2.2 s and 3.5 ± 6.4 s respectively). Further studies are warranted to further understand the mechanisms by which this therapeutic effect may be conveyed, and which of the novel aspects of the very high and ultra high frequency stimulation strategies may have contributed to the improvement in seizure abatement performance when compared to standard electrical stimulation approaches.  相似文献   
33.
The migratory behaviour and spatial area use of sympatric Arctic charr Salvelinus alpinus and brown trout Salmo trutta were investigated during their marine feeding migration. The likelihood of finding individuals of both species in the inner or outer fjord areas was dependent on water temperature in the inner area (especially for S. alpinus), the temperature difference between the inner and outer areas (especially for S. trutta) and fish fork length (both species). The strongest predictor was the water temperature in the inner area, and particularly S. alpinus left this area and moved to the outer areas with increasing temperatures in the inner area. At 8° C in the inner area, the likelihood of finding S. alpinus in the outer areas was >50%. This predictor had a smaller effect on S. trutta, and the likelihood of finding S. trutta in the outer areas only started to increase at around 14° C. The relationships between temperature and area use did not correspond to the species' optimal growth temperatures, but to their previously documented temperature preferences. Individuals of both species used mainly the littoral fjord areas, and to a lesser extent the pelagic areas. In conclusion, temperature differences between the inner and outer marine areas probably resulted in the segregated area use between the species, because water temperatures or factors influenced by temperature affected their migratory behaviour and habitat use differently. The results indicate that increased marine temperatures with global warming may lead to increased spatial overlap between S. trutta and S. alpinus, which again may lead to increased interspecific competition during their marine phase, and with S. alpinus probably being the more negatively affected.  相似文献   
34.
Surface layer proteins (S-layer) of Lysinibacillus sphaericus JG-B53 are biological compounds with several bio-based technical applications such as biosorptive materials for metal removal or rare metals recovery from the environment. Despite their well-described applications, a deeper understanding of their metal sorption behavior still remains challenging. The metal sorption ability of Au3+, Pd2+, Pt2+ and Eu3+ was investigated by ICP-MS, AFM and QCM-D which enables the sorption detection in real-time during in situ experiments. Results indicate a high binding of Pd, followed by Au, Eu and Pt to the proteins. The comparison between different methods allowed a deeper understanding of the metal sorption of isolated S-layer either frees in liquid, adsorbed forming a protein layer or as the bacteria surface.  相似文献   
35.

Background

Patients with ST-elevation myocardial infarction (STEMI) not treated with primary or rescue percutaneous coronary intervention (PCI) are at risk for recurrent ischemia, especially when viability in the infarct-area is present. Therefore, an invasive strategy with PCI of the infarct-related coronary artery in patients with viability would reduce the occurrence of a composite end point of death, reinfarction, or unstable angina (UA).

Methods

Patients admitted with an (sub)acute myocardial infarction, who were not treated by primary or rescue PCI, and who were stable during the first 48 hours after the acute event, were screened for the study. Eventually, we randomly assigned 216 patients with viability (demonstrated with low-dose dobutamine echocardiography) to an invasive or a conservative strategy. In the invasive strategy stenting of the infarct-related coronary artery was intended with abciximab as adjunct treatment. Seventy-five (75) patients without viability served as registry group. The primary endpoint was the composite of death from any cause, recurrent myocardial infarction (MI) and unstable angina at one year. As secondary endpoint the need for (repeat) revascularization procedures and anginal status were recorded.

Results

The primary combined endpoint of death, recurrent MI and unstable angina was 7.5% (8/106) in the invasive group and 17.3% (19/110) in the conservative group (Hazard ratio 0.42; 95% confidence interval [CI] 0.18-0.96; p = 0.032). During follow up revascularization-procedures were performed in 6.6% (7/106) in the invasive group and 31.8% (35/110) in the conservative group (Hazard ratio 0.18; 95% CI 0.13-0.43; p < 0.0001). A low rate of recurrent ischemia was found in the non-viable group (5.4%) in comparison to the viable-conservative group (14.5%). (Hazard-ratio 0.35; 95% CI 0.17-1.00; p = 0.051).

Conclusion

We demonstrated that after acute MI (treated with thrombolysis or without reperfusion therapy) patients with viability in the infarct-area benefit from a strategy of early in-hospital stenting of the infarct-related coronary artery. This treatment results in a long-term uneventful clinical course. The study confirmed the low risk of recurrent ischemia in patients without viability.

Trial registration

ClinicalTrials.gov: NCT00149591.  相似文献   
36.
For the efficient surface presentation and release of virulence factors especially pathogenic Gram-negative bacteria have developed several distinct secretion mechanisms. An increasing number of pathogens in various species employs a mechanism denoted the 'autotransporter' pathway. This pathway is characterised by an outer membrane translocator module representing the C-terminal domain of the transported protein itself. An intriguing potential application of such systems involves the transport and surface expression of recombinant proteins or peptides, like e.g. the presentation of antigens for the generation of live oral vectors as vaccine carriers. Here we report on the incorporation of heterologous (poly-) peptides in permissive sites of the translocator module of the adhesin-involved-in-diffuse-adherence (AIDA) autotransporter system. We demonstrate the presentation of the B subunit of the heat labile enterotoxin of Escherichia coli (LTB) as well as of functional T-cell epitopes of Yersinia enterocolitica heat-shock protein 60 (Y-hsp60) on the surface of E. coli.  相似文献   
37.
Ernst A  Suhr J  Köhrle J  Bergmann A 《Peptides》2008,29(7):1201-1206
Substance P (SP) is a neuropeptide that is released from sensory nerves and several types of immune cells. It is involved in the transmission of pain and has a number of pro-inflammatory effects. Like other neuropeptides, SP is derived from a large precursor peptide, protachykinin A (PTA). Alternative splicing results in the production of four distinct PTA molecules that all contain the sequence of SP and a common N-terminal region consisting of 37 amino acids. We have developed a sandwich immunoassay using antibodies against the N-terminal part of PTA. Here we demonstrate that N-terminal PTA immunoreactivity is present in human circulation and cerebrospinal fluid (CSF). The concentration was about 90 times higher in CSF than in EDTA-plasma. Analytical reversed phase HPLC revealed that NT-PTA 1-37 is the main immunoreactivity in human circulation and CSF. Moreover, compared to the low in vitro stability of SP of less than 12 min, NT-PTA immunoreactivity is absolutely stable in EDTA-plasma and CSF for more than 48 h. As NT-PTA 1-37 is produced in stoichiometric amounts and is theoretically co-released with SP, we suggest the measurement of NT-PTA immunoreactivity as surrogate molecule for the release of bioactive SP.  相似文献   
38.
We have constructed hybrid retrovirus packaging cell lines that express the gibbon ape leukemia virus env and the Moloney murine leukemia virus gag-pol proteins. These cells were used to produce a retrovirus vector at over 10(6) CFU/ml, with a host range that included rat, hamster, bovine, cat, dog, monkey, and human cells. The gag-pol and env expression plasmids were separately transfected to reduce the potential for helper virus production, which was not observed. The NIH 3T3 mouse cells from which the packaging lines were made are not infectable by gibbon ape leukemia virus; thus, the generation and spread of possible recombinant viruses in the packaging cells is greatly reduced. These simian virus-based packaging cells extend the host range of currently available murine and avian packaging cells and should be useful for efficient gene transfer into higher mammals.  相似文献   
39.
40.
Sorption of ethylene oxide during and after gaseous sterilization is influenced by numerous factors. It was found that ethylene oxide desorption not only depends on material to be fumigated but also to a considerable degree on the wrapping material. Although polyethylene, polyamide (nylon), polytetrafluoroethylene (Teflon), silicone, aluminum, and glass beads contained no quantities of ethylene oxide detectable by gas chromatography after 72 h of aeration, residual amounts were definitely determined, even after 76 h of aeration in polypropylene, polystyrene, polyvinylchloride, paper products, and compound products of various plastics and paper mixtures. Desorption was, in all cases, found to be better when a mixture of ethylene oxide and methyl formate was used instead of pure ethylene oxide.  相似文献   
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