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81.
Supramolecular complexes consisting of ruthenium chromophores and a cisplatin unit represent an emerging class of bioactive molecules of interest as anti-cancer agents. Although the ability of Ru(II)/Pt(II) heteronuclear complexes to bind to DNA has been demonstrated, the in vivo activity of these complexes has not yet been reported. In the present work, we report the anti-bacterial activity of the complex [(tpy)RuCl(dpp)PtCl(2)](PF(6)) (where dpp=2,3-bis(2-pyridyl)pyrazine, tpy=2,2':6',2'-terpyridine). The impact on bacterial cell growth of exposure to different concentrations of [(tpy)RuCl(dpp)PtCl(2)](PF(6)) and cisplatin was studied. The bioactivity of this complex was found to be due to the presence of the cis-PtCl(2) moiety, as the monometallic synthon [(tpy)RuCl(dpp)](PF(6)) did not inhibit bacterial cell growth.  相似文献   
82.

Introduction

The mechanisms by which selective serotonin re-uptake inhibitors (SSRI) act in depressed patients remain unknown. The serotonergic neurotransmitter system and the hypothalamic-pituitary-adrenal (HPA) system may interact. The aim of the AGENDA trial was to investigate whether long-term intervention with SSRI versus placebo affects the cortisol response in the dexamethasone corticotropin-releasing hormone (DEX-CRH) test in healthy first-degree relatives to patients with major depressive disorder (MDD).

Methods

Eighty healthy first-degree relatives to patients with MDD were randomized to escitalopram 10 mg versus matching placebo daily for four weeks. The primary outcome measure was the intervention difference in the change of the total area under the curve (CorAUCtotal) for plasma cortisol in the DEX-CRH test at entry to after four weeks of intervention.

Results

Change in CorAUCtotal showed no statistically significant difference between the escitalopram and the placebo group, p = 0.47. There were large intra- and inter-individual differences in the results of the DEX-CRH test. There was statistically significant negative correlation between the plasma escitalopram concentration and change in CorAUCtotal, rho = −0.41, p = 0.01. Post-hoc analyses showed a statistically significant interaction between age and intervention group and change in log CorAUCtotal.

Conclusion

The present trial does not support an effect of escitalopram 10 mg daily compared with placebo on the HPA-axis in healthy first-degree relatives to patients with MDD. Increasing levels of escitalopram tended to decrease the HPA-response in the DEX-CRH test and this effect increased with age.

Trial Registration

ClinicalTrials.gov [NCT00386841  相似文献   
83.
Zusammenfassung 1974–1983 waren in einem mit 600 künstlichen Nisthöhlen ausgestatteten Lärchen-Versuchsforst (52.27 N, 7.15 E) bei Lingen/Emsland beim Trauerschnäpper 20,7% der nachweislich mit einem polygamen verpaart. Neben 51 Bigynie-Fällen konnte auch 4mal Trigynie nachgewiesen werden. mit Polygamie-Nachweis waren im Mittel älter als die übrigen (2,71 bzw. 2,18 Jahre). Polygame hatten im Durchschnitt längere Flügel und ein größeres Gewicht als ohne Polygamie-Nachweis, was als Folge der unterschiedlichen Altersstruktur zu deuten ist. Brutkästen der Bigamisten waren im Mittel 258 m voneinander entfernt (Maximum 750 m). Bei Bruten ohne Nachweis eines fütternden lag die Anzahl ausgeflogener Junge (im Mittel 2,9) gesichert unter dem Bruterfolg von zwei anderen Gruppen (fütterndes bei einer Brut festgestellt 4,7; fütterndes bei 2–3 Bruten festgestellt 4,5). Zwischen den Schlüpfterminen von Bigamisten-Bruten lagen 1–16 Tage. Das Durchschnittsalter der in den jeweils früheren Bruten betrug 2,67, in den jeweils späteren Bruten 1,67 Jahre.
Polygyny in the Pied Flycatcher (Ficedula hypoleuca) at the western border of its Central European range
Summary 1974–1983 in a study area of larch forest (52.27 N, 7.15 E), with 600 nestboxes, near Lingen/Emsland in western Lower Saxony, polygyny among Pied Flycatchers was identified as participation of in feeding at 2 or 3 nestboxes (bigyny or trigyny). 20.7% of were shown to be paired with a polygamous . Beside 51 cases of bigyny 4 cases of trigyny were identified. The incidence of polygyny was also considered in relation to the border situation of the study area. Proven polygamous were on average older than other (2.71 as compared to 2.18 years). On average polygamous had longer wings and greater bodyweight than without polygamous record, which is to be interpreted as a result of differing age structure. On average the mean distance between nestboxes of bigamists was 258 m (max. 750 m). In cases of broods without recorded feeding (generally this would occur in cases of secondary broods of polygamous in which the assisted only rarely or not at all) the number of reared young (on average 2.9) was significantly lower than the breeding success realised by 2 other groups ( recorded as assisting in rearing one brood only 4.7; recorded as assisting in rearing 2–3 broods 4.5). A period of 1–16 days (on average 7) elapsed between the hatching dates of broods of bigamists. The average age of in the earlier broods was 2.67 yrs, in the later broods 1.67 yrs.


Gefördert mit Hilfe von Forschungsmitteln des Landes Niedersachsen.  相似文献   
84.
CD20 Abs induce clinical responses in lymphoma patients, but there are considerable differences between individual patients. In (51)Cr release assays with whole blood as effector source, RAJI cells were effectively killed by a mouse/human chimeric IgG1 construct of CD20 Ab 1F5, whereas ARH-77 proved resistant to killing by this Ab. When whole blood was fractionated into plasma, mononuclear cells, or granulocytic effector cells, RAJI cells were effectively killed in the presence of complement-containing plasma, whereas the mature B cell line ARH-77 proved complement resistant. However, with a bispecific Ab (BsAb) against the myeloid receptor for IgA (CD89; FcalphaRI) and CD20, a broad range of B cell lines were effectively killed. FcalphaRI is expressed on monocytes/macrophages, neutrophils, and eosinophils. As the numbers of these effector cells and their functional activity can be enhanced by application of G-CSF or GM-CSF, lysis via (FcalphaRI x CD20) BsAb was significantly enhanced in blood from patients during therapy with these myeloid growth factors. Interestingly, the major effector cell population for this BsAb were polymorphonuclear neutrophils, which proved ineffective in killing malignant B cells with murine, chimeric IgG1, or FcgammaRI- or FcgammaRIII-directed BsAbs against CD20. Experiments with blood from human FcalphaRI/FcgammaRI double-transgenic mice showed corresponding results, allowing the establishment of relevant syngenic animal models in these mice. In conclusion, the combination of myeloid growth factors and an (FcalphaRI x CD20) BsAb may represent a promising approach to improve effector cell recruitment for CD20-directed lymphoma therapy.  相似文献   
85.
Bordetella pertussis can attach, invade and survive intracellularly in human macrophages in vitro. To study the significance of this bacterial feature in vivo, we analyzed the presence of viable bacteria in broncho-alveolar lavage (BAL) cells of mice infected with B. pertussis. We found B. pertussis to be present in a viable state in BAL fluid cells until at least 19 days after infection, suggesting B. pertussis to be able to survive in those cells. This intracellular niche may play an important role in the pathogenesis of pertussis. Pertussis toxin and the RGD sequence of the virulence factor filamentous hemagglutinin (FHA) both play a role in the attachment of B. pertussis to human and mouse macrophages in vitro and we hypothesized these virulence factors to be required for invasion and subsequent intracellular survival of B. pertussis in macrophages in vivo. A B. pertussis double mutant, in which the FHA RGD motif was changed to RAD and the ptx genes were deleted, was also found in a viable state in BAL fluid cells, albeit at lower levels than the wild-type strain. In our model, uptake of B. pertussis by alveolar phagocytes in vivo is thus, at least in part, determined by the bacterial virulence factors FHA and pertussis toxin.  相似文献   
86.

Background

Snake bite is a common medical emergency in Papua New Guinea (PNG). The taipan, Oxyuranus scutellatus, inflicts a large number of bites that, in the absence of antivenom therapy, result in high mortality. Parenteral administration of antivenoms manufactured in Australia is the current treatment of choice for these envenomings. However, the price of these products is high and has increased over the last 25 years; consequently the country can no longer afford all the antivenom it needs. This situation prompted an international collaborative project aimed at generating a new, low-cost antivenom against O. scutellatus for PNG.

Methodology/Principal Findings

A new monospecific equine whole IgG antivenom, obtained by caprylic acid fractionation of plasma, was prepared by immunising horses with the venom of O. scutellatus from PNG. This antivenom was compared with the currently used F(ab'')2 monospecific taipan antivenom manufactured by CSL Limited, Australia. The comparison included physicochemical properties and the preclinical assessment of the neutralisation of lethal neurotoxicity and the myotoxic, coagulant and phospholipase A2 activities of the venom of O. scutellatus from PNG. The F(ab'')2 antivenom had a higher protein concentration than whole IgG antivenom. Both antivenoms effectively neutralised, and had similar potency, against the lethal neurotoxic effect (both by intraperitoneal and intravenous routes of injection), myotoxicity, and phospholipase A2 activity of O. scutellatus venom. However, the whole IgG antivenom showed a higher potency than the F(ab'')2 antivenom in the neutralisation of the coagulant activity of O. scutellatus venom from PNG.

Conclusions/Significance

The new whole IgG taipan antivenom described in this study compares favourably with the currently used F(ab'')2 antivenom, both in terms of physicochemical characteristics and neutralising potency. Therefore, it should be considered as a promising low-cost candidate for the treatment of envenomings by O. scutellatus in PNG, and is ready to be tested in clinical trials. Author Summary Snake bite envenoming represents an important public health hazard in Papua New Guinea (PNG). In the southern lowlands of the country the majority of envenomings are inflicted by the taipan, Oxyuranus scutellatus. The only currently effective treatment for these envenomings is the administration of antivenoms manufactured in Australia. However, the price of these products in PNG is very high and has steadily increased over the last 25 years, leading to chronic antivenom shortages in this country. As a response to this situation, an international partnership between PNG, Australia and Costa Rica was initiated, with the aim of generating a new, low-cost antivenom for the treatment of PNG taipan envenoming. Horses were immunised with the venom of O. scutellatus from PNG and whole IgG was purified from the plasma of these animals by caprylic acid precipitation of non-immunoglobulin proteins. The new antivenom, manufactured by Instituto Clodomiro Picado (Costa Rica), was compared with the currently available F(ab'')2 antivenom manufactured by CSL Limited (Australia). Both were effective in the neutralisation of the most relevant toxic effects induced by this venom, although the whole IgG antivenom showed a higher efficacy than the F(ab'')2 antivenom in the neutralisation of the coagulant activity.  相似文献   
87.
Zusammenfassung Im Mittel der Jahre 1957–1988 wurden bei Braunschweig (52.16 N/10.32 E) für die Kohlmeise 163 (Eichen-Hainbuchenwald), 90 (Laub-/Kiefernwald-Mischbestand) bzw. 55 (Kiefernforst) Brutpaare · 100 ha–1 festgestellt. Beim Trauerschnäpper lagen die entsprechenden Zahlen bei 276, 250 bzw. 97. Die maximale Brutpaar-Dichte war bei der Kohlmeise um den Faktor 3,8 bis 4,3 und beim Trauerschnäpper um den Faktor 1,9 bis 2,6 höher als die jeweilige minimale Brutpaar-Dichte. Für den Trauerschnäpper ergab sich ein gesichert positiver Zusammenhang zwischen Erfolgsbruten-Zahl und Brutpaar-Dichte im jeweils folgenden Jahr. Bei der Kohlmeise war die Korrelation nicht signifikant. Der Bestandsverlauf der Kohlmeise zeigt eine gesicherte Zunahmetendenz, während sich für den Trauerschnäpper kein signifikanter Langzeit-Trend ergab. Beim Trauerschnäpper war die Brutpaar-Dichte von 1964–1975 gesichert höher als in den Zeiträumen 1957–1963 und 1976–1988 (Abb.).
Longterm trends of Great Tits (Parus major) and Pied Flycatchers (Ficedula hypoleuca): Results in Lower Saxony
Summary From 1957 to 1988, the numbers of breeding pairs of Great Tits and Pied Flycatchers were ascertained in three nestbox equipped areas in the vicinity of Braunschweig/Lower Saxony (52.16 N/10.32 E; Tab. 1). In the Great Tits on average 163 breeding pairs per 100 hectares were registered in oak/hornbeam forest, 90 in mixed deciduous and pine forest, and 55 in pure pine forest. Corresponding figures for Pied Flycatchers were 276, 250, and 97. Maximum breeding pair density as compared to minimum density was greater by a factor of between 3.8 and 4.3 in the case of Great Tits, in the case of Pied Flycatchers it was greater by the factor of between 1.9 and 2.6. In the Pied Flycatchers a significantly positive correlation was established between the numbers of successful broods and breeding pair density in the year following. No significant correlation was found in the Great Tits. Density trends of Great Tits show a significant tendency of growth (summary of area data, see fig.) whilst no significant long term trend was recognisable for Pied Flycatchers. From 1964 to 1975 Pied Flycatcher breeding pair density was significantly greater than in the periods from 1957 to 1963 and from 1976 to 1988 (see fig.).
  相似文献   
88.
The theta-logistic model of density regulation is an especially flexible class of density regulation models where different forms of non-linear density regulation can be expressed by only one parameter, θ. Estimating the parameters of the theta-logistic model is, however, challenging. This is mainly due to the need for information concerning population growth at low densities as well as data on fluctuations around the carrying capacity K in order to estimate the strength of density regulation. Here we estimate parameters of the theta-logistic model for 28 populations of three species of birds that have grown from very small population sizes followed by a period of fluctuations around K. We then use these parameters to estimate the quasi-stationary distribution of population size. There were often large uncertainties in these parameters specifying the form of density regulation that were generally independent of the duration of the study period. In contrast, precision in the estimates of environmental variance increased with the length of the time series. In most of the populations, a large proportion of the probability density of the (quasi-) stationary distribution of population sizes was located at intermediate population sizes relative to K. Thus, we suggest that the (quasi-) stationary distribution of population sizes represents a useful summary statistic that in many cases provides a more robust characterisation of basic population dynamics (e.g. range of variation in population fluctuations or proportion of time spent close to K) than can be obtained from analyses of single model parameters.  相似文献   
89.
We studied the variations in N‐linked glycosylation of human IgG molecules derived from 105 different stable cell lines each expressing one of the six different antibodies. Antibody expression was based on glutamine synthetase selection technology in suspension growing CHO‐K1SV cells. The glycans detected on the Fc fragment were mainly of the core‐fucosylated complex type containing zero or one galactose and little to no sialic acid. The glycosylation was highly consistent for the same cell line when grown multiple times, indicating the robustness of the production and glycan analysis procedure. However, a twofold to threefold difference was observed in the level of galactosylation and/or non‐core‐fucosylation between the 105 different cell lines, suggesting clone‐to‐clone variation. These differences may change the Fc‐mediated effector functions by such antibodies. Large variation was also observed in the oligomannose‐5 glycan content, which, when present, may lead to undesired rapid clearance of the antibody in vivo. Statistically significant differences were noticed between the various glycan parameters for the six different antibodies, indicating that the variable domains and/or light chain isotype influence Fc glycosylation. The glycosylation altered when batch production in shaker was changed to fed‐batch production in bioreactor, but was consistent again when the process was scaled from 400 to 5,000 L. Taken together, the observed clone‐to‐clone glycosylation variation but batch‐to‐batch consistency provides a rationale for selection of optimal production cell lines for large‐scale manufacturing of biopharmaceutical human IgG. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009  相似文献   
90.
The electromyographical (EMG) response to isometric ramp contractions of the right arm, the left arm, and both arms was studied using four pairs of surface electrodes above the right upper trapezius muscle (UT) of six men and six women. Contractions were made against gravity with the active arm(s) in eight positions, ranging from flexion to abduction. To describe arm positions, new, simple terminology was developed. Root mean square (rms)-converted EMG-signals were normalized (EMGnorm) with respect to a reference contraction. The EMGnorm corresponding to a 15 N.m torque in the right glenohumeral (GH) joint was strongly related to the position of the right arm (P less than 0.001). The shape of this relationship depended on the electrode position (P less than 0.001). The ratio between EMGnorm at 30 N.m and 15 N.m GH torques was related to arm position (P less than 0.001) and differed between electrodes (P less than 0.001). A left-side GH torque resulted in right-side (contralateral) EMG activity, typically corresponding to 20%-30% of that obtained during similar right-side GH torque. Bilateral GH torque implied 0%-50% increase in EMG activity as compared to that obtained with the right arm alone. The results have shown that signals from one pair of surface electrodes above UT cannot be taken as representative of the EMG activity from electrodes located elsewhere above UT. The EMG recordings reflected a complex pattern of muscular activation, significantly related to both outwardly visible factors (arm position, GH torque), and within-body servosystems (motor control reflexes).  相似文献   
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