10,383 research outputs found
Subtyping of Properdin Factor B (Bf) by Isoelectrofocusing
No full textProperdin factor B (Bf) is a polymorphic protein in the human plasma. Two common alleles, BfS, BfF, and two rare alleles, BfF1, BfS1, have been demonstrated in Caucasians. We now report that BfF can be subtyped into two alleles, BfFa and BfFb by isoelectrofocusing. Family studies indicate that they are inherited in a co-dominant pattern. Gene frequencies for Caucasians are: BfS 0.808, BfF1 0.019, Bfs1 0.005, Bfs1 0.038 and BfFa 0.128
Genetic polymorphism of factor B (Bf) in Okayama Prefecture, Japan.
No full textThe genetic polymorphism of factor B (Bf) was investigated in Okayama Prefecture, Japan. Cellogel immunofixation electrophoresis was employed according to Martin and Ziegler (1981) with minor modifications. In 316 non-blood related Japanese, the Bf was: Bf S, 70.6%; Bf FS, 27.8%; and Bf F, 1.6%. No rare variants were observed. The gene frequencies of Bfs and BfF were 0.845 and 0.155, respectively. The gene frequencies in Okayama Prefecture were quite similar to those in other districts of Japan. Considering the phenotype distribution in Japan, the Bf system might be a useful marker for personal identification and in disputed paternity cases.</p
Genetic polymorphism of factor B (Bf) in Okayama Prefecture, Japan.
No full textThe genetic polymorphism of factor B (Bf) was investigated in Okayama Prefecture, Japan. Cellogel immunofixation electrophoresis was employed according to Martin and Ziegler (1981) with minor modifications. In 316 non-blood related Japanese, the Bf was: Bf S, 70.6%; Bf FS, 27.8%; and Bf F, 1.6%. No rare variants were observed. The gene frequencies of Bfs and BfF were 0.845 and 0.155, respectively. The gene frequencies in Okayama Prefecture were quite similar to those in other districts of Japan. Considering the phenotype distribution in Japan, the Bf system might be a useful marker for personal identification and in disputed paternity cases.</p
Amyloid tracers detect multple binding sites in Alzheimer´s disease brain tissue.
No full textImaging fibrillar amyloid-β deposition in the human brain in vivo by positron emission tomography has improved our understanding of the time course of amyloid-β pathology in Alzheimer’s disease. The most widely used amyloid-β imaging tracer so far is 11C-Pittsburgh compound B, a thioflavin derivative but other 11C- and 18F-labelled amyloid-β tracers have been studied in patients with Alzheimer's disease and cognitively normal control subjects. However, it has not yet been established whether different amyloid tracers bind to identical sites on amyloid-β fibrils, offering the same ability to detect the regional amyloid-β burden in the brains. In this study, we characterized 3H-Pittsburgh compound B binding in autopsied brain regions from 23 patients with Alzheimer's disease and 20 control subjects (aged 50 to 88 years). The binding properties of the amyloid tracers FDDNP, AV-45, AV-1 and BF-227 were also compared with those of 3H-Pittsburgh compound B in the frontal cortices of patients with Alzheimer's disease. Saturation binding studies revealed the presence of high- and low-affinity 3H-Pittsburgh compound B binding sites in the frontal cortex (Kd1: 3.5 ± 1.6 nM; Kd2: 133 ± 30 nM) and hippocampus (Kd1:5.6 ± 2.2 nM; Kd2: 181 ± 132 nM) of Alzheimer's disease brains. The relative proportion of high-affinity to low-affinity sites was 6:1 in the frontal cortex and 3:1 in the hippocampus. One control showed both high- and low-affinity 3H-Pittsburgh compound B binding sites (Kd1: 1.6 nM; Kd2: 330 nM) in the cortex while the others only had a low-affinity site (Kd2: 191 ± 70 nM). 3H-Pittsburgh compound B binding in Alzheimer's disease brains was higher in the frontal and parietal cortices than in the caudate nucleus and hippocampus, and negligible in the cerebellum. Competitive binding studies with 3H-Pittsburgh compound B in the frontal cortices of Alzheimer's disease brains revealed high- and low-affinity binding sites for BTA-1 (Ki: 0.2 nM, 70 nM), florbetapir (1.8 nM, 53 nM) and florbetaben (1.0 nM, 65 nM). BF-227 displaced 83% of 3H-Pittsburgh compound B binding, mainly at a low-affinity site (311 nM), whereas FDDNP only partly displaced (40%). We propose a multiple binding site model for the amyloid tracers (binding sites 1, 2 and 3), where AV-45 (florbetapir), AV-1 (florbetaben), and Pittsburgh compound B, all show nanomolar affinity for the high-affinity site (binding site 1), as visualized by positron emission tomography. BF-227 shows mainly binding to site 3 and FDDNP shows only some binding to site 2. Different amyloid tracers may provide new insight into the pathophysiological mechanisms in the progression of Alzheimer’s disease
BF bursting amplitude predicts RT modulation between S-Large and S-Small trials.
No full text<p>(A) Bursting responses of one representative BF neuron to S-Large and S-Small onset. Individual trials in raster plots were aligned to sound onset and sorted by RT (blue). (B) Population PSTH (mean ± sem) for BF bursting neurons (<i>n</i> = 144) showed stronger bursting to S-Large than to S-Small. The mean RTs for the corresponding trials were indicated in the inset (mean ± std, <i>n</i> = 40 sessions). (C) Scatter plot of the mean bursting amplitude for each BF bursting neuron in S-Large versus S-Small trials from one session. Each dot represents one BF bursting neuron (<i>n</i> = 144), with red dots representing neurons recorded during the first three sessions after reversal (<i>n</i> = 14). (D) Correlation between BF bursting amplitude modulation and mean RT modulation in one session, each calculated as a ratio between S-Large and S-Small trials. Results plotted separately for individual BF bursting neurons (gray), as well as for the entire bursting population per session during the first three reversal sessions (red) or afterwards (blue). Between S-Large and S-Small trials in a session, BF bursting strength was strongly correlated with the modulation of mean RT.</p
Risk factors for incidence and persistence of disability in chronic major depression and alcohol use disorders: longitudinal analyses of a population-based study
No full textBackgroundMajor depression and alcohol use disorders are risk factors for incidence of disability. However, it is still unclear whether a chronic course of these health conditions is also prospectively associated with incidence of disability. The aim of the present study was, first, to confirm whether chronic major depression (MD) and alcohol use disorders (AUD) are, respectively, risk factors for persistence and incidence of disability in the general population; and then to analyze the role of help-seeking behavior in the course of disability among respondents with chronic MD and chronic AUD. MethodData from two assessments in the National Epidemiologic Survey on Alcohol and Related Conditions were analyzed. Disability was measured by eight domains of the Short Form 12 Health Survey version 2 (SF-12). Generalized estimating equations and logistic regression models were run to estimate risk factors for persistence and incidence of disability, respectively. ResultsAnalyses conducted on data from the US general population showed that chronic MD was the strongest risk factor for incidence and persistence of disability in the social functioning, emotional role and mental health domains. Chronic AUD were risk factors for incidence and persistence of disability in the vitality, social functioning, and emotional role domains. Within the group of chronic MD, physical comorbidity and help-seeking were associated with persistent disability in most of the SF-12 domains. Help-seeking behavior was also associated with incidence of problems in the mental health domain for the depression group. Regarding the AUD group, comorbidity with physical health problems was a strong risk factor for persistence of disability in all SF-12 domains. Help-seeking behavior was not related to either persistence or incidence of disability in the chronic alcohol group. ConclusionsChronic MD and chronic AUD are independent risk factors for persistence and incidence of disability in the US general population. People with chronic MD seek help for their problems when they experience persistent disability, whereas people with chronic AUD might not seek any help even if they are suffering from persistent disability.<br/
Two-site evaluation of the diagnostic performance of the Sysmex XN Body Fluid (BF) module for cell count and differential in Cerebrospinal Fluid
No full textINTRODUCTION: Cellular analysis in cerebrospinal fluid (CSF) provides important diagnostic information in many pathological settings. The aim of this two-site study was to evaluate the Sysmex XN Body Fluid mode (XN-BF) for cell analysis of CSF compared to light microscopy (LM). METHODS: Two hundred and seven consecutive CSF samples were analyzed in parallel with XN-BF and LM. The study also included the estimation of the limit of blank (LoB), limit of detection (LoD), limit of quantitation (LoQ), carry-over and linearity of XN-BF module. RESULTS: LoQ of white blood cells (WBC) was 3×106 cells/L; linearity was good and carry-over negligible. XN-BF parameters were compared to LM for the following cell classes: total cells, WBC, polymorphonuclear (PMN), and mononuclear (MN) cells. The bias ranged from 1.3 to 15.2×106 cells/L. The receiver operating characteristics curve analysis for WBC showed an area under the curve of 0.98, and the global diagnostic agreement was 95% at a cutoff of 5×106 cells/L. CONCLUSIONS: XN-BF provides rapid and accurate counts in clinically relevant ranges of CSF values, thus providing a valuable alternative to conventional LM analysis. However, microscopic review remains advisable in samples with abnormal cell counts or high fluorescent (HF-BF) cell parameter exceeding 5×106 cells/L
Expression of Bf/C2 Gene(S) in the Japanese Medaka Fish
No full textComplement factor B and C2 are two central serine proteases of the alternative and classical complement pathways, respectively, that serve as the catalytic subunits of the C3 convertase. Research has been completed using a female Japanese medaka fish, (Oryzias latipes), and other teleost and elasmobrach species in order to isolate eDNA clones and perform linkage analysis of the Bf/C2 gene(s). To further analyze the evolution of the complement system in teleosts, different tissues than the ones from previous studies of medaka fish were analyzed for the constitutive gene expression of factor B and C2. Bf/C2 sequences were amplified by reverse transcription-polymerase chain reaction with primers corresponding to the common amino acid sequences shared by mammalian Bf and C2. Agarose gel electrophoresis was used to visualize sample bands and to calculate the concentration of gene expression of the Bf/C2 gene(s) in each tissue. All five tissue types, kidney, liver, muscle, testis, and spleen from a male medaka fish demonstrated Bf/C2 gene(s) expression, confirming that the messages of Bf/C2 gene(s) are distributed throughout the medaka fish. Tissues of the spleen, liver, and kidney contained the highest concentrations of expression of Bf/C2 gene( s ), while tissues of the muscle and testis contained the lowest concentrations. This research also determined that RT-PCR allowed for more sensitive analysis of gene expression than other molecular biology techniques such as Northern blotting analysis
THE ELECTRONIC SPECTRUM OF BF
No full textAuthor Institution: Division of Pure Physics, National Research Council of CanadaThe electronic spectrum of BF has been photographed in absorption at high resolution in the region from to . The emission spectrum has been investigated between and . Several new singlet states, which lie 75,000 to above the ground state, were found in absorption. Rotational constants have been determined for nearly 20 states, including the previously well-known X, A, B, C, and D states. Analysis of the emission and absorption spectra has permitted the reassignment of several transitions which had been seen previously only in emission. A discussion of the nature of the excited electronic states of BF will be presented
Selective Blue-Filtering (S-BF) lens protected RPE cells from blue light irradiation-induced cytotoxicity.
No full text(A) Under blue LED irradiation, S-BF lens showed significantly elevated viability compared to the UV-filtering (UVF) lens (93.4±1.4% vs 90.6±1.4%) using trypan blue (p = 0.022) assay. (B) MTT assay also revealed that S-BF lens increased cellular viability by 22.5% (p = 0.029). (n = 3, t-test, * p<0.05).</p
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