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11.
Partial trisomy 12 in a mentally retarded boy and translocation (12;21) in his mother 总被引:2,自引:1,他引:2
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Cytogenetic studies of an infant with malformations and a peculiar appearance showed a partial trisomy of chromosome 12. The mother carried a translocation of the distal part of chromosome 12 onto the short arm of chromosome 21, with breakpoints most likely at 12q24 and 21p11. 相似文献
12.
Hinda J. Ahmed Catharina Johansson Liselott A. Svensson Karin Ahlman Margareta Verdrengh Teresa Lagergrd 《Infection and immunity》2002,70(2):899-908
We investigated the phagocytosis of Haemophilus ducreyi both in vitro and in vivo. Human granulocyte and monocyte phagocytosis of opsonized and nonopsonized, fluorescence-labeled H. ducreyi was assessed by flow cytometry. Both Escherichia coli and noncapsulated H. influenzae were included as controls. The maximal percentage of granulocytes taken up by H. ducreyi was 35% after 90 min. In contrast, 95% of H. influenzae bacteria were phagocytosed by granulocytes after 30 min. These results indicated that H. ducreyi phagocytosis was slow and inefficient. Bacterial opsonization by using specific antibodies increased the percentage of granulocytes phagocytosing H. ducreyi from 24 to 49%. The nonphagocytosed bacteria were completely resistant to phagocytosis even when reexposed to granulocytes, indicating that the H. ducreyi culture comprised a mixture of phenotypes. The intracellular survival of H. ducreyi in granulocytes, in monocytes/macrophages, and in a monocyte cell line (THP-1) was quantified after application of gentamicin treatment to kill extracellular bacteria. H. ducreyi survival within phagocytes was poor; approximately 11 and <0.1% of the added bacteria survived intracellularly after 2 and 20 h of incubation, respectively, while no intracellular H. influenzae bacteria were recovered after 2 h of incubation with phagocytes. The role of phagocytes in the development of skin lesions due to H. ducreyi was also studied in vivo. Mice that were depleted of granulocytes and/or monocytes and SCID mice, which lacked T and B cells, were injected intradermally with approximately 106 CFU of H. ducreyi. Within 4 days of inoculation, the granulocyte-depleted mice developed lesions that persisted throughout the experimental period. This result reinforces the importance of granulocytes in the early innate defense against H. ducreyi infection. In conclusion, H. ducreyi is insufficiently phagocytosed to achieve complete eradication of the bacteria. Indeed, H. ducreyi has the ability to survive intracellularly for short periods within phagocytic cells in vitro. Since granulocytes play a major role in the innate defense against H. ducreyi infection in vivo, bacterial resistance to phagocytosis probably plays a crucial role in the pathogenesis of chancroid. 相似文献
13.
Multilocus sequence typing of Swedish invasive group B streptococcus isolates indicates a neonatally associated genetic lineage and capsule switching
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Luan SL Granlund M Sellin M Lagergård T Spratt BG Norgren M 《Journal of clinical microbiology》2005,43(8):3727-3733
Streptococcus agalactiae, also designated group B streptococcus (GBS), is an important pathogen in neonates, pregnant women, and nonpregnant adults with predisposing conditions. We used multilocus sequence typing (MLST) to characterize 158 GBS isolates that were associated with neonatal and adult invasive disease and that were collected in northern and western Sweden from 1988 to 1997. Five major genetic lineages (sequence type [ST] 19, ST-17, ST-1, ST-23, and ST-9 complexes) were identified among the isolates, including serotype Ia, Ib, and II to V isolates, indicating a highly clonal population structure among invasive GBS isolates. A number of STs were found to contain isolates of different serotypes, which indicates that capsule switching occurred rather frequently. Two distantly related genetic lineages were identified among isolates of serotype III, namely, clonal complex 19 (CC19), and CC17. CC19 was equally common among isolates from adult and neonatal disease (accounting for 10.3% of GBS isolates from adult disease and 18.7% from neonatal disease), whereas CC17 significantly appeared to be associated with neonatal invasive disease (isolated from 21.9% of neonatal isolates but only 2.6% of adult isolates). The distribution of the mobile elements GBSi1 and IS1548 reveals that they can act as genetic markers for lineages CC17 and CC19, respectively. 相似文献
14.
Gene profiling reveals increased expression of uteroglobin and other anti-inflammatory genes in glucocorticoid-treated nasal polyps 总被引:3,自引:0,他引:3
Benson M Carlsson L Adner M Jernås M Rudemo M Sjögren A Svensson PA Uddman R Cardell LO 《The Journal of allergy and clinical immunology》2004,113(6):58-1143
BACKGROUND: Treatment with local glucocorticoids (GCs) decreases symptoms and the size of nasal polyps. This might depend on the downregulation of proinflammatory genes, as well as the upregulation of anti-inflammatory genes. OBJECTIVE: We sought to identify GC-regulated anti-inflammatory genes in nasal polyps. METHODS: Affymetrix DNA microarrays were used to analyze the expression of 22,283 genes in 4 nasal polyps before and after local treatment with fluticasone (400 microg/d). Expression of uteroglobin and mammaglobin B was analyzed with real-time PCR in 6 nasal polyps and in nasal biopsy specimens from 6 healthy control subjects. RESULTS: Two hundred three genes had changed in expression in treated polyps, and 139 had known functions: 54 genes were downregulated, and 85 were upregulated. Genes associated with inflammation constituted the largest single functional group. These genes affected key steps in inflammation (eg, immunoglobulin production; antigen processing and presentation; and the chemoattraction and activation of granulocytes, T cells, and B cells). Several proinflammatory genes were downregulated. In contrast, some anti-inflammatory genes were upregulated. The gene that increased most in terms of expression was uteroglobin. This was confirmed with real-time PCR. By contrast, expression of uteroglobin was lower in untreated polyps than in healthy nasal mucosa. Immunohistochemical investigation showed staining of uteroglobin in the epithelium and in seromucous glands in control subjects and in nasal polyps. CONCLUSION: Upregulation of anti-inflammatory genes, such as uteroglobin, might contribute to the effects of local treatment with GCs in nasal polyps. 相似文献
15.
Background
Rhizoma Curculiginis (Xianmao) and Rhizoma Drynariae (Gusuibu) are 'Yang-tonifying' traditional Chinese herbal medicines used to strengthen bones. This investigation aims to assess the systemic effect of extracts of Rhizoma Curculiginis and Rhizoma Drynariae on bone histomorphology and formation, and their local effect on bone healing. 相似文献16.
Bjrn Folkow Margareta Hallback Yen Lundgren Lilian Weiss 《Acta physiologica (Oxford, England)》1972,84(4):512-523
Newborn litters of spontaneously hypertensive rats (SHR) and normotensive control rats (NCR) were identically treated with sympathetic nerve growth factor antiserum (Wellcome) which markedly interferes with adrenergic cardiovascular control (Zaimis 1967). Blood pressure, measured intermittently during 8 months, was in treated SHR (SHRis) about 25 % higher than in NCRis, their respective pressures being about 40 % and 25 % lower than those of sham-treated SHR and NCR.–The hindquarters of one SHRis, or NCRis, were then perfused at constant flow in parallel with those of ordinary NCR. Starting from maximal vasodilatation, resistance increases were induced by graded noradrenaline (NA) infusions, from “threshold” to maximal pressor responses. Compared to NCRis, SHRis showed an increased resistance at maximal dilatation, an increased slope of the NA dose-response curve and an increased maximal pressor response, while their NA “thresholds” did not differ significantly. Thus, the structurally determined hemodynamic differences between ordinary SHR and NCR (Folkow et al. 1970 b) characterize also SHRis and NCRis, though to a reduced extent. Even when comparing SHRis with ordinary- NCR, which exhibited similar “resting” pressures, these differences partly remain, suggesting that the SHR resistance vessels might, for genetic reasons, be more prone to adapt structurally to pressure loads than those of NCR. 相似文献
17.
Summary An outbreak of aseptic meningitis in association with ECHO virus type 4 is described. This virus was isolated in 8 out of 12 cases with this syndrome from stool specimens and in two cases also from spinal fluids and furthermore from healthy family contacts. Neutralizing antibodies in the patients sera could not be demonstrated with the conventional tube tests while complement fixing antibodies with increasing titer against ECHO-4 occurred. There is an extensive heterotypic complement fixing antibody response in patients sera within the ECHO virus group between this group and the Coxsackie or the poliomyelitis group as well as beetwen the Coxsackie and the poliomyelitis groups.The choice of tissue for isolation of enteroviruses is discussed. Trypsinized human embryonic kidney seems to provide a suitable medium for this group of viruses.A rubella-like exanthem was seen in about two thirds of the virus positive patients. Some cases had diphasic course. 相似文献
18.
Myeloperoxidase in human lung lavage 总被引:2,自引:0,他引:2
Birgitta Schmekel Yngve Hörnblad Margareta Linden Christer Sundström Per Venge 《Inflammation》1990,14(4):455-461
Bronchial wash and bronchoalveolar lavage were performed in 12 healthy subjects (five smokers), in order to elucidate whether or not material of neutrophil origin may be phagocytized by lung macrophages in vivo. Cells from different levels in the bronchial tree were obtained by sequential injection and subsequent aspiration of either four 50-ml or five 10-ml aliquots. Each aliquot was used for the determination of total and differential cell counts. The proportion of myeloperoxidase-positive alveolar macrophages was determined by specific immune histochemical staining. The percentage of myeloperoxidase-positive macrophages was highest (median 94.8%, range 37-98.5%) in the 10-ml aliquots and lowest in the last three 50-ml aliquots (median values 1-2.5%) (P less than 0.001). A significant correlation was obtained between the fraction of myeloperoxidase-positive macrophages and the percentage count of bronchoalveolar lavage neutrophils (r = 0.466, P less than 0.05). Furthermore, the cellular myeloperoxidase showed a significant inverse correlation (r = -0.46, P less than 0.05) to the viability of the bronchoalveolar lavage cells. Our findings are compatible with previous demonstrations in animals of neutrophil phagocytosis by lung macrophages and show that this phenomenon in particular occurs in the more proximal airways. The internalization of neutrophils or neutrophil components by airway macrophages may be an important scavenger mechanism for protection of the lung from the deleterious effects of activated neutrophils. 相似文献
19.
The aim of the present study was to assess the influence of ageing on cardiac function and coronary flow in Wistar Kyoto normotensive rats (WKY, 16 and 78 weeks of age) and spontaneously hypertensive rats (SHR) of the same age. Cardiac function was determined on isolated hearts by means of an antegrade heart perfusion technique. Left atrial pressure and peak aortic pressure could be altered independently of each other. Recordings of cardiac output and coronary flow were then obtained at both normotensive and hypertensive levels of peak aortic pressures. Peak stroke volume (SV) was reduced with age in both WKY and SHR. Peak SV determined at normotensive pressure loads became diminished with age in WKY, while it at hypertensive pressure loads showed a small decline with age, since peak SV was low as early as 16 weeks of age. The age-dependent fall in cardiac performance was greater in SHR than in WKY, due to the enhanced peak SV in 16-week-old SHR at hypertensive pressure loads. Peak SV was markedly decreased at normotensive pressure levels in both 16- and 78-week-old SHR v. age-matched WKY. Coronary flow per unit tissue declined with age both in WKY and SHR. Coronary flow was also lower in SHR compared to age-matched WKY. With ageing this elevated performance was reduced down to the same level as in 78-week-old WKY. The age-related coronary flow reduction and the consistently reduced flow in SHR indicate a structural narrowing of the coronary vascular bed, particularly in SHR. 相似文献
20.
Margareta Böttiger 《Archives of virology》1971,35(2-3):251-255
Summary Sera derived from children immunized against poliomyelitis by different procedures showed variations in their ability to neutralize different poliovirus type 3 strains. Sera from children immunized with inactivated vaccine neutralized the strain incorporated in the vaccine better than the other strains tested; the sera were 5 times less active against a wild type 3 strain. Groups of sera derived from similar vaccinees who in addition had obtained a booster of live vaccine did not deviate from this pattern of reaction.Sera of children receiving oral vaccine only (Sabin 3 or Usol-D bac) showed a different pattern of reaction. These sera neutralized both the vaccine strain used and the wild strain tested to approximately the same degree. 相似文献