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21.
High diversity of ankA sequences of Anaplasma phagocytophilum among Ixodes ricinus ticks in Germany 下载免费PDF全文
von Loewenich FD Baumgarten BU Schröppel K Geissdörfer W Röllinghoff M Bogdan C 《Journal of clinical microbiology》2003,41(11):5033-5040
In Germany humans with acute granulocytic ehrlichiosis have not yet been described. Here, we characterized three different genes of Anaplasma phagocytophilum strains infecting German Ixodes ricinus ticks in order to test whether they differ from strains in other European countries and the United States. A total of 1,022 I. ricinus ticks were investigated for infection with A. phagocytophilum by nested PCR and sequence analysis. Forty-two (4.1%) ticks were infected. For all positive ticks, parts of the 16S rRNA and groESL genes were sequenced. The complete coding sequence of the ankA gene could be determined in 24 samples. The 16S rRNA and groESL gene sequences were as much as 100% identical to known sequences. Fifteen ankA sequences were >/=99.37% identical to sequences derived from humans with granulocytic ehrlichiosis in Europe and from a horse with granulocytic ehrlichiosis in Germany. Thus, German I. ricinus ticks most likely harbor A. phagocytophilum strains that can cause disease in humans. Nine additional sequences were clearly different from known ankA sequences. Because these newly described sequences have never been obtained from diseased humans or animals, their biological significance is currently unknown. Based on this unexpected sequence heterogeneity, we propose to use the ankA gene for further phylogenetic analyses of A. phagocytophilum and to investigate the biology and pathogenicity of strains that differ in the ankA gene. 相似文献
22.
Number of C-bands of human isochromosome Xqi and relation to 45,X mosaicism 总被引:1,自引:1,他引:1 下载免费PDF全文
Lillian Y. F. Hsu Sophie Paciuc Karen David Steluta Cristian Ralph Moloshok Kurt Hirschhorn 《Journal of medical genetics》1978,15(3):222-226
With combination of C and G banding techniques, three morphologically different types of isochromosome for the long arm of X (Xqi) have been identified, i.e. those with one C-band and symmetrical banding patterns of both arms, those with two C-bands and symmetrical banding patterns of two arms, and those with two C-bands but with asymmetrical banding patterns of two arms. The last type is a heterogeneous group with various different asymmetrical patterns. We have studied 6 cases of Xqi with C, G, and Q banding: 3 showed one C-band and symmetrical arms and all these were without 45,X mosaicism; the other 3 cases showed two C-bands, 2 of the cases having symmetrical arms and being mosaic for 45X/46,XXqi/47,XXqiXqi (those 2 were a pair of identical twins). One other had asymmetrical arms and was mosaic for 45,X/46,XXqi. Including our 6 cases, there have been a total of 30 reported cases of Xqi with C and G banding studies. Two-thirds of Xqi's were found to have 2 C-bands and one-third to have 1 C-band. Mosaicism was found in 85% of Xqi's with 2 C-bands and in only 44% of Xqi's with 1 C-band. Apparently, Xqi's with 2 C-bands have a greater tendency for anaphase lag and mitotic nondisjunction. Several possible mechanisms for the formation of the different types of Xqi's are discussed. 相似文献
23.
Bogdan Karakašević 《Medical microbiology and immunology》1955,142(1):27-37
Ohne Zusammenfassung 相似文献
24.
25.
Expression of inducible nitric oxide synthase in skin lesions of patients with american cutaneous leishmaniasis 下载免费PDF全文
Cytokine-inducible (or type 2) nitric oxide synthase (iNOS) is indispensable for the resolution of Leishmania major or Leishmania donovani infections in mice. In contrast, little is known about the expression and function of iNOS in human leishmaniasis. Here, we show by immunohistological analysis of skin biopsies from Mexican patients with local (LCL) or diffuse (DCL) cutaneous leishmaniasis that the expression of iNOS was most prominent in LCL lesions with small numbers of parasites whereas lesions with a high parasite burden (LCL or DCL) contained considerably fewer iNOS-positive cells. This is the first study to suggest an antileishmanial function of iNOS in human Leishmania infections in vivo. 相似文献
26.
Magnesium-inhibited, TRPM6/7-like channel in cardiac myocytes: permeation of divalent cations and pH-mediated regulation 总被引:5,自引:0,他引:5
27.
Prokopowicz M Banecki B Lukasiak J Przyjazny A 《Journal of biomaterials science. Polymer edition》2003,14(2):103-118
The paper investigates the conformational stability of bovine serum albumin (BSA) and fibrinogen during 24-h incubation in turn with a linear silicone polymer (polydimethylsiloxane (PDMS)), with linear silicone oligomers (hexamethyldisiloxane and octamethyltrisiloxane) and with cyclic silicone oligomers (octamethylcyclotetrasiloxane (D4) and decamethylcyclopentasiloxane (D5)). Ten-fold and 100-fold excesses of siloxanes with respect to the proteins were used. Using fluorescence spectroscopy of tryptophan located in the domain of proteins and fluorescence of 8-anilino-1-naphthalenesulfonic acid (1,8-ANS), which interacts with hydrophobic domains of proteins, changes in the tertiary structure of the protein were recorded. The results demonstrated that BSA does not change its native form during 24-h incubation with siloxanes. In contrast, the tertiary structure of fibrinogen was found to be altered by both short-chain linear siloxanes: (hexamethyldisiloxane and octamethyltrisiloxane) and long-chain PDMS. The changes can be observed only at a 100-fold excess of siloxanes with respect to the protein. No conformational changes in fibrinogen exposed to cyclic siloxanes were observed. 相似文献
28.
Steffen Stenger Werner Solbach Martin Rllinghoff Christian Bogdan 《European journal of immunology》1991,21(7):1669-1675
Tumor necrosis factor-alpha (TNF-alpha) strongly activates murine peritoneal macrophages (M phi) for killing of amastigotes from Leishmania major in the presence of low amounts of interferon-gamma (IFN-gamma). Recently, we found that IFN-gamma and interleukin 4 (IL 4) also synergistically enhance the antileishmanial potential of M phi. In this report, evidence is provided that the synergism of IFN-gamma and IL 4 is based on the ability of the lymphokines to induce the endogenous production of TNF-alpha. First, both IFN-gamma and IL 4 as single agents and in combination were potent inducers of TNF-alpha production by M phi infected with L. major amastigotes. Second, the synergistic effect of IFN-gamma and IL 4 on parasite killing by M phi strongly correlated with their synergistic effect on the release of TNF-alpha. Third, the IFN-gamma/IL 4-mediated parasite elimination was completely abrogated not only in the presence of antibodies to IFN-gamma and IL 4, but also with an antibody specific for TNF-alpha. Consistent with the conclusion that endogenously produced TNF-alpha accounts for the synergism of IL 4 with IFN-gamma is the finding that N omega-monomethyl-L-arginine, an inhibitor of the L-arginine-dependent generation of microbicidal nitrogen intermediates, totally blocked the M phi activation induced by IFN-gamma combined with IL 4 as well as by IFN-gamma combined with TNF-alpha. These results underline the complex interplay of cytokines derived from lymphocytes and M phi and the role of TNF-alpha as pivotal factor for the induction of antileishmanial effector functions. 相似文献
29.
Micromorphometry and spermatozoa binding patterns of fertilized and unfertilized human oocytes after in-vitro fertilization 总被引:2,自引:1,他引:2
Human oocytes (n = 380) from 71 in-vitro fertilization patientswere measured 18 h after insemination to find out if certainparameters of oocyte morphology could be related to fertilization.In addition, the number and distribution patterns of spermatozoabound to or within the zona pellucida of 534 oocytes were analysed.The mean diameter of the human oocyte was 167.7 ± 9.5µm and its mean volume was 2.5 x 106 µm3. Therewere no significant differences in diameter between 112 fertilizedand 168 unfertilized oocytes, although they displayed differencesin the size of the perivitelline space and the zona pellucida.The age of the patients had no significant effect on the morphometryof the oocytes. Sperm binding patterns did not correlate withfertilization. The number and distribution of the spermatozoaon the surface of the zona pellucida was extremely heterogeneousand was not related to the occurrence of fertilization. Allpossible binding and distribution patterns were in the samerange in both fertilized and unfertilized oocytes. In conclusion,the micromorphometry of human oocytes and their sperm bindingpatterns were not related to the occurrence of fertilization. 相似文献
30.
A 69-year-old man presented with cough, shortness of breath, and fatigue. He was initially treated for allergies and then for pulmonary embolism. Radiologically, a tumor mass was found to occlude the right pulmonary artery and involve the pulmonary trunk. A right pneumonectomy was performed. Histologically, a cellular malignant spindle and epithelioid tumor with areas of necrosis and brisk mitotic activity was seen. In some areas, the tumor appeared to form vascular channels. Focal osteosarcomatous differentiation was present. Immunohistochemical studies were performed including vimentin, smooth muscle actin, desmin, CD31, CD34, S100, and pan-cytokeratin. The tumor cells were positive for CD31 and vimentin and negative for pan-cytokeratin, CD34, and S100. Two months after surgery, the patient was alive and well. 相似文献