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1.
The nervous system of Tricladida. II. Neuroanatomy ofDugesia tigrina (Paludicola,Dugesiidae): An immunocytochemical study 总被引:2,自引:0,他引:2
2.
The effect of weak static (DC) and alternating (AC) magnetic fields (MFs), as well as combined (AC/DC) collinear MFs on the intensity of morphogenesis processes in the planarian Dugesia (Girardia) tigrina has been studied. It was found that combined MFs produce a stimulating effect on the fission and regeneration of planarians. Both components of the combined MFs, the direct (DC) and the alternating (AC), are important in the realization of the effects of weak MFs. The practically complete absence of one of the components (DC) reverses the sign of the effect. It was shown that the presence of concomitant background MFs does not substantially influence the effects of combined MFs with a very small AC component (100 nT). The effect of the "zero" field is significant and comparable in magnitude with the effects of combined MFs at effective frequencies. Narrow zones of effective amplitudes (in the region of tens and hundreds of nT) of the AC component of the combined MFs, with the DC component close to the value of the geomagnetic field were found, which alternate with regions where the response of the biological object to the influence is absent. 相似文献
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4.
Kreshchenko ND Sedelnikov Z Sheiman IM Reuter M Maule AG Gustafsson MK 《Cell and tissue research》2008,331(3):739-750
The effects of neuropeptide F (NPF; from Moniezia expansa) on the regeneration of Girardia tigrina were studied. The animals were decapitated and incubated in water (control) or NPF. The dynamics of the proliferation of
the neoblasts in the developing tissue were studied during the course of regeneration by monitoring the mitotic index (MI).
The effects of incubation in FMRFamide and GYIRFamide on the MI were also tested. The course of cephalic regeneration was
followed with in vivo computer-assisted morphometry for up to 7 days. The development of the regenerating nervous system and
the musculature was visualised by immunostaining with a primary antiserum to the C-terminal decapeptide of NPF (YFAIIGRPRFa)
and tetramethylrhodamine-isothiocyanate-conjugated phalloidin, which stains F-actin in muscle filaments. The study showed
that NPF had a stimulatory effect on the mitotic activity of the neoblasts. FMRFamide and GYIRFamide did not have this effect.
NPF also stimulated the growth of the regenerating head and the growing nervous system and musculature. NPF is postulated
to have a morphogenetic action in the regenerating animals.
This work was supported by two grants from the Finnish Academy of Science (nos. 202685, 2004) and (no. 112090, 2006) to M.G.,
an RFBR grant (07-04-00452a) to N.K. and a Wellcome Trust grant (069411) to A.G.M. for which we express our gratitude. 相似文献
5.
Treatment of patients diagnosed as schizophrenic with antipsychotic drugs (neuroleptics) is known to cause occasional unexplained depletion of white blood cells, especially neutrophil granulocytes. It has been known for many years that neuroleptics can interfere with the mitochondrial respiratory chain in vitro. Because there has been a growing interest recently in mitochondrial targeting of drugs, and since a quantitative structure-activity relationship (QSAR) model that predicts mitochondrial accumulation of neuroleptics has been published, we investigated the effects of neuroleptics on white blood cell mitochondria. Venous blood samples were collected from both patients undergoing treatment with neuroleptics and healthy volunteers. The samples were processed for transmission electron microscopy. The resulting images of white blood cells were analyzed using stereology to compare quantitatively mitochondrial morphology in the patient and control groups. We found that in patients, but not in controls, there was swelling of mitochondria and fragmentation of the mitochondrial cristae. There also were fewer mitochondria in patients than in controls, although due to the swelling of the organelles, the volume density of mitochondria in the two groups was not significantly different. Such changes are typical of a toxic insult. Consequently, it seems plausible that, since schizophrenia is not a disease considered to affect white blood cells per se, these changes probably are due to the medication. 相似文献
6.
S.P. NG Z.G. LI B.W. CHEN Z.K. QIN M.M. GARCIA S.W.K. IM M.H. NG 《Journal of Rapid Methods and Automation in Microbiology》1997,5(4):285-294
We previously described an enrichment-immunoassay utilizing a T6 monoclonal antibody capture enzyme-linked immunosorbent assay. Here we evaluated it for the rapid screening for Salmonella in fishmeal obtained from the national Animal and Plant Quarantine service in the People's Republic of China. In this method, the number of Salmonella present is first expanded by appropriate enrichment cultures, and the pathogens are then directly detected by the T6 immunoassay. In a total of 94 enrichment cultures of fishmeal, we obtained an overall concordance of 98% between the results obtained in parallel by this method and by conventional test method. The positive prediction by this method was 92% and the negative prediction was 100%. The turn around time for the new test was 27 h which is a significant improvement from the turn around time exceeding 96 h required for the conventional test method. This test proved to be compatible with the routine work flow in the practical setting of a quarantine laboratory. 相似文献
7.
Eveline C van Asbeck Andy IM Hoepelman Jelle Scharringa Bjorn L Herpers Jan Verhoef 《BMC microbiology》2008,8(1):229
Background
Mannose binding lectin (MBL) is an important host defence protein against opportunistic fungal pathogens. This carbohydrate-binding protein, an opsonin and lectin pathway activator, binds through multiple lectin domains to the repeating sugar arrays displayed on the surface of a wide range of clinically relevant microbial species. We investigated the contribution of MBL to antifungal innate immunity towards C. parapsilosis in vitro. 相似文献8.
Treatment of patients diagnosed as schizophrenic with antipsychotic drugs (neuroleptics) is known to cause occasional unexplained depletion of white blood cells, especially neutrophil granulocytes. It has been known for many years that neuroleptics can interfere with the mitochondrial respiratory chain in vitro. Because there has been a growing interest recently in mitochondrial targeting of drugs, and since a quantitative structure-activity relationship (QSAR) model that predicts mitochondrial accumulation of neuroleptics has been published, we investigated the effects of neuroleptics on white blood cell mitochondria. Venous blood samples were collected from both patients undergoing treatment with neuroleptics and healthy volunteers. The samples were processed for transmission electron microscopy. The resulting images of white blood cells were analyzed using stereology to compare quantitatively mitochondrial morphology in the patient and control groups. We found that in patients, but not in controls, there was swelling of mitochondria and fragmentation of the mitochondrial cristae. There also were fewer mitochondria in patients than in controls, although due to the swelling of the organelles, the volume density of mitochondria in the two groups was not significantly different. Such changes are typical of a toxic insult. Consequently, it seems plausible that, since schizophrenia is not a disease considered to affect white blood cells per se, these changes probably are due to the medication. 相似文献
9.
The idea of immunological surveillance against cancer has existed for nearly 100 years but as no conclusive evidence has yet
been published the importance of the cellular immune defense in the detection and removal of incipient or existing tumors
is still a hotly debated subject. However, in order to select a relevant immunotherapeutic strategy in the treatment of cancer,
a fundamental understanding of the basic immunologic conditions under which a tumor develops and exists is a prerequisite.
Therefore, a murine model was set up that we hoped would enable us to confirm or reject the theory of immunological surveillance.
A large panel of methylcholanthrene induced tumors was established in T-cell immunodeficient nude mice and congenic normal
mice to study the influence of the immune system on developing tumors. As nude mice developed tumors fastest and with the
highest incidence, we concluded that in this model the immune system constituted a ‘tumor-suppressive factor’ delaying and
sometimes abrogating tumor growth, i.e. performing immune surveillance. Immunogenicity of the tumors was assessed by transplantation
back to normal histocompatible mice. Tumors originating from the immunodeficient nude mice turned out to be far more immunogenic
than tumors from normal mice, resulting in a high rejection rate. CD8+cytotoxic T cells were found to be indispensable for
this rejection, leading to the conclusion that the cytotoxic T cells perform immune selection in normal mice, eliminating
immunogenic tumor cell variants in the incipient tumor.
In this review, we discuss the difficulties facing immunotherapy when conclusions are drawn from the presented observations
and hypotheses. 相似文献
10.
Jae Chul SHIM Dong-Kyu LEE Terry A. KLEIN Heung-Chul KIM Won-Ja LEE Heung Ku IM 《Entomological Research》2010,40(4):202-210
After re-emergence of malaria in 1993, a continued increase in Plasmodium vivax cases was observed from 1993 to 2006 in northern Gyeonggi and Gangwon Provinces adjacent to the demilitarized zone separating North from South Korea. Annual parasite incidence per 1000 people ranged from 0.33 in 2004 to 0.89 in 2006. While malaria case rates declined (22.6%) in 2004, they increased 75.1% in 2005 and 51.7% in 2006 from the previous years. An initial incorrect diagnosis of 46.8% of malaria cases as common cold resulted in a mean delay of 1.3 days for the detection malarial parasites. Of the total cases, 10.2% from December to May were due to latent intrinsic incubation infections acquired the previous malaria season and the rest of the cases from June to November were either latent or short incubation infections. Overall, the peak anopheline population occurred from July to September, resulting in a similar peak in malaria cases. While malaria cases increased during 2005–2006, anopheline populations, based on trap indices, were not significantly different during 4 years of surveillance. To decrease the malaria patient infective period to mosquitoes, public health centers in Paju and Cheorwon in 2006 prescribed chloroquine + primaquine at days 0–3 after initial malaria diagnosis followed by an additional 11 days of primaquine (early primaquine treatment), rather than chloroquine on days 0–3 and primaquine on days 4–17 (delayed primaquine treatment). A reduction in the malaria parasite incidence during 2007 was recorded for the two locations offering the early primaquine treatment relative to other locations using the delayed primaquine treatment. 相似文献