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11.
Walter Bessler 《Oral Radiology》1993,9(1):61-72
Current Activities of the Japanese Society for Oral and Maxillofacial Radiology, 1992
Abstracts—Dental radiology vol. 32, 1992 相似文献12.
Huber M Ayoub M Pfannes SD Mittenbühler K Weis K Bessler WG Baier W 《European journal of medical research》2000,5(3):101-109
The bacterial extract OM-89 used for the prevention and treatment of recurrent urinary tract infections constitutes an effective immunostimulant in vitro and in vivo. Here we demonstrate that OM-89 shows mitogenic properties towards murine spleen cell cultures from LPS responder and non-responder mice. In macrophages the extract induces the translocation of NF-kappaB into the cell nucleus and RNI (radical nitrogen intermediates) release, which could be attributed to single fractions of the extract. Our findings on the in vitro immunostimulatory effect of OM-89, as well as its immunogenic and adjuvant properties, are of importance for understanding its therapeutic efficacy as demonstrated in clinical studies. 相似文献
13.
WG Mitchell H Lynn JF Bale MA Maeder SM Donfield B Garg AH Tilton JK Willis TP Bohan 《Pediatrics》1997,100(5):817-824
BACKGROUND: Boys and young men with hemophilia treated with factor infusions before 1985 had a substantial risk of acquiring the human immunodeficiency virus (HIV) and the acquired immunodeficiency syndrome. This study was designed to assess the effects of HIV and hemophilia per se on neurological function in a large cohort of subjects with hemophilia, and to investigate the relationships between neurological disease and death during follow-up. METHODS: Three hundred thirty-three boys and young men (207 HIV seropositive and 126 HIV seronegative) were evaluated longitudinally in a multicenter, multidisciplinary study. Neurological history and examination were conducted at baseline and annually for 4 years. The relationship between neurological variables, HIV serostatus, CD4+ cell counts, and vital status at the conclusion of the study was examined using logistic regression models. RESULTS: The risks of nonhemophilia-associated muscle atrophy, behavior change, and gait disturbance increased with time in immune compromised HIV-seropositive subjects compared with HIV seronegative or immunologically stable HIV-seropositive subjects. The risk of behavior change in immune compromised HIV-seropositive hemophiliacs, for example, rose to 60% by year 4 versus 10% to 17% for the other study groups. Forty-five subjects (13.5%), all of whom were HIV seropositive, died by year 4. Subjects who died had had increased risks of hyperreflexia, nonhemophilia-associated muscle atrophy, and behavior change. CONCLUSIONS: These results indicate that immune compromised, HIV-seropositive hemophiliacs have high rates of neurological abnormalities over time and that neurological abnormalities were common among subjects who later died. By contrast, immunologically stable HIV-seropositive subjects did not differ from the HIV-seronegative participants. Hemophilia per se was associated with progressive abnormalities of gait, coordination, and motor function. 相似文献
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BACKGROUND: Clinical observations indicate that patients with Alzheimer's disease show a greater susceptibility to infections. One possible explanation is that this predisposition is due to alterations in their immune system. OBJECTIVE: To investigate this assumption, pro- and anti-inflammatory cytokines, as well as the phagocytic activity and superoxide anion generation was examined in aged individuals with and without Alzheimer's disease. METHODS: The production of IL-1beta, IL-2, IL-6, TNFalpha and IL-10 by peripheral blood mononuclear cells from 12 patients with Alzheimer's disease was compared with that of 12 age-matched individuals without any signs of dementia and 12 middle-aged healthy volunteers who served as an additional control. The engulfing capacity of the phagocytic cells was detected by counting cells containing latex beads and the number of particles internalized by each individual cell. RESULTS: The secretion of IL-2 was markedly low in the demented patients, compared with both elderly and middle-aged subjects. IL-1beta and TNFalpha production was similar in the individuals of the 3 groups. The production of IL-6 and IL-10 was significantly lower when compared to that of the middle-aged, but did not differ between the elderly patients with and without dementia. The phagocytic function of both polymorphonuclear cells and monocytes was decreased in individuals of the elderly groups with a low number of engulfed latex particles by each individual polymorphonuclear cell. The production of superoxide anions was increased only by monocytes from the elderly groups. CONCLUSIONS: The results suggest that although the impaired immune function in patients with Alzheimer's disease is related to the aging process, the significant low IL-2 production in these patients may play a role in their increased susceptibility to infections. 相似文献
16.
Specific defect in N-acetylglucosamine incorporation in the biosynthesis of the glycosylphosphatidylinositol anchor in cloned cell lines from patients with paroxysmal nocturnal hemoglobinuria. 总被引:4,自引:1,他引:4 下载免费PDF全文
P Hillmen M Bessler P J Mason W M Watkins L Luzzatto 《Proceedings of the National Academy of Sciences of the United States of America》1993,90(11):5272-5276
Paroxysmal nocturnal hemoglobinuria (PNH) is a clonal disorder arising in a multipotent hemopoietic stem cell. PNH manifests clinically with intravascular hemolysis resulting from an increased sensitivity of the red cells belonging to the PNH clone to complement-mediated lysis. Numerous studies have shown that surface proteins anchored to the membrane via a glycosylphosphatidylinositol (GPI) anchor (including proteins protecting the cell from complement) are deficient on the cells of the PNH clone, leading to the notion that GPI-anchor biosynthesis may be abnormal in these cells. To investigate the biochemical defect underlying PNH we have used lymphoblastoid cell lines (LCLs) with the PNH phenotype obtained by Epstein-Barr virus immortalization of lymphocytes from nine patients with PNH. By labeling cells with myo-[3H]inositol we have found that PNH LCLs produce phosphatidylinositol normally. By contrast, PNH LCLs fail to incorporate [3H]mannose into GPI anchor precursors. When cell-free extracts of PNH LCLs and normal LCLs obtained from the same patients (and expected therefore to be isogeneic except for the PNH mutation) were incubated with uridine diphospho-N-acetyl[3H]glucosamine (UDP-[3H]GlcNAc), we observed complete failure or marked reduction in the production of N-acetylglucosaminyl(alpha-1,6)phosphatidylinositol and glucosaminyl(alpha-1,6)phosphatidylinositol by the PNH LCLs in all cases. These findings pinpoint the block in PNH at an early stage in the biosynthesis of the GPI anchor, suggesting that the defective enzyme is UDP-GlcNAc:phosphatidylinositol-alpha-1,6-N- acetylglucosaminyltransferase. The existence of PNH type III cells and type II cells is probably explained by the transferase deficiency being total or partial, respectively. 相似文献
17.
BRCA1 and BRCA2 are major breast cancer susceptibility genes. Nineteen single nucleotide polymorphisms (SNPs) at 18 loci have been associated with breast cancer. We aimed to determine whether these predict breast cancer incidence in women with BRCA1/BRCA2 mutations. BRCA1/2 mutation carriers identified through the Manchester genetics centre between 1996 and 2011 were included. Using published odds ratios (OR) and risk allele frequencies, we calculated an overall breast cancer risk SNP score (OBRS) for each woman. The relationship between OBRS and age at breast cancer onset was investigated using the Cox proportional hazards model, and predictive ability assessed using Harrell's C concordance statistic. In BRCA1 mutation carriers we found no association between OBRS and age at breast cancer onset: OR for the lowest risk quintile compared to the highest was 1.20 (95% CI 0.82–1.75, Harrell's C = 0.54), but in BRCA2 mutation carriers the association was significant (OR for the lowest risk quintile relative to the highest was 0.47 (95% CI 0.33–0.69, Harrell's C = 0.59). The 18 validated breast cancer SNPs differentiate breast cancer risks between women with BRCA2 mutations, but not BRCA1. It may now be appropriate to use these SNPs to help women with BRCA2 mutations make maximally informed decisions about management options. 相似文献
18.
High resolution of heterogeneity among human neutrophil granules: physical, biochemical, and ultrastructural properties of isolated fractions 总被引:4,自引:1,他引:4
Previous studies on the fractionation of human neutrophil granules have identified two major populations: myeloperoxidase (MPO)-containing azurophil, or primary, granules and MPO-deficient specific, or secondary, granules. Peripheral blood neutrophils from individual donors were lysed in sucrose-free media by either hypotonic shock or nitrogen cavitation. Using a novel two-gradient Percoll density centrifugation system, the granule-rich postnuclear supernatant was rapidly (ten minutes) and reproducibly resolved into 13 granule fractions (L1 through L8 and H1 through H5). Granule flotation and recentrifugation experiments on both continuous, self-generated and multiple-step gradients using individual and mixed isolated fractions demonstrated that the banding patterns were isopycnic and nonartifactual. Isolated granules were intact based on the findings that biochemical latency of several granule enzymes was greater than 95%, and thin-sectioned electron micrographs demonstrated intact granule profiles. Biochemical analyses of the granule marker proteins MPO, beta-glucuronidase, lysozyme, and lactoferrin indicated that a number of the fractions were related to the major azurophil and specific granule populations. Lactoferrin was found in ten of 13 fractions (L1 through L8, H1 to H2), whereas MPO was found in every fraction. Consistent with these biochemical data, all fractions exhibited varying degrees of heterogeneity based on ultrastructural morphology and cytochemistry, including diaminobenzidine (DAB) reactivity for peroxidase and periodate-thiocarbohydrazide-silver proteinate (PA-TCH-SP) staining for complex glycoconjugates. A variable but significant percentage (23% to 70%) of the granules in fractions L1 through L8 and H1 and H2 showed DAB reactivity, while about 90% of the granules in fractions H3 through H5 were peroxidase positive. These results demonstrated that DAB-reactive granules spanned the entire range of granule size and density. Ultrastructural PA-TCH-SP staining of isolated granule fractions revealed patterns similar to those of granules in intact neutrophils at different stages of development. Granules from human acute promyelocytic leukemia cells (HL-60) exhibited a surprisingly low density compared with typical azurophil granules from normal, mature neutrophils. The data suggest that both functional and maturational differences contribute to granule heterogeneity, and provide a new practical and conceptual framework for further defining the phenomenon of neutrophil granule heterogeneity. 相似文献
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20.
Woloszynek JR Rothbaum RJ Rawls AS Minx PJ Wilson RK Mason PJ Bessler M Link DC 《Blood》2004,104(12):3588-3590
Shwachman-Diamond Syndrome (SDS) is a rare multisystem disorder characterized by exocrine pancreatic insufficiency, bone marrow dysfunction, and metaphyseal chondrodysplasia. Recent studies show that mutations of SBDS, a gene of unknown function, are present in the majority of patients with SDS. In the present study, we show that most, but not all, patients classified based on rigorous clinical criteria as having SDS had compound heterozygous mutations of SBDS. Full-length SBDS protein was not detected in leukocytes of SDS patients with the most common SBDS mutations, consistent with a loss-of-function mechanism. In contrast, SBDS protein was expressed at normal levels in SDS patients without SBDS mutations. These data confirm the absence of SBDS mutations in this subgroup of patients and suggest that SDS is a genetically heterogeneous disorder. The presence (or absence) of SBDS mutations may define subgroups of patients with SDS who share distinct clinical features or natural history. 相似文献