Functional morphology of nucleolus organizer regions of chromosomes and nucleoli in human multiple myeloma cell lines. I. Variation of the morphology and silver staining of nucleolus organizer regions of chromosomes in RMPI 8226 and U 266 cell lines with different level of differentiation of during 7 days after cell passage

The morphology and Ag-staining of nucleoli in human multiple myeloma cell lines RPMI 8226 and U 266, distinguished from each other in the differentiation degree, were quantitatively studied, and the production of immunoglobulins or their fragments by the line cells was evaluated throughout 7 days after cell seeding. The less differentiated cell line RPMI 8226 and the high differentiated cell line U 266 were revealed to differ in both the initial level of immunoglobulin production and dynamics of immunoglobulin accumulation in culture medium. The total number of Ag-stained nucleolar-organizer regions (AgNORs) per nucleus in cells RPMI 8226 was significantly higher than in cells U 266 in all times after seeding of the cells. In both cell lines changes in the quantity and shape of nucleoli and also in the total number of AgNORs per nucleus and pattern of AgNORs distribution within nucleoli correlated with the cell cycle phase. Relationships between morphofunctional changes in nucleoli and the differentiation degree and proliferative activity of the cells, and also between the number of Ag-positive nucleolar-organizing metaphase chromosomes and the functional activity of interphase AgNORs are discussed.     

The effect of curcumin on human B-cell immortalization by Epstein-Barr virus

Cyclosporine is a commonly used immunosuppressant in solid-organ transplantation. It is, however, associated with an increased incidence of Epstein-Barr virus (EBV)induced post-transplant lymphoproliferative disorder (PTLD). In this study, human B lymphocytes isolated from healthy volunteers were immortalized in vitro with EBV. The effect of oxidative stress mediated by cyclosporine A or hydrogen peroxide on in vitro B cell immortalization was studied by coculturing immortalized B cells with cyclosporine A and hydrogen peroxide. Curcumin, a phenolic extract of the spice turmeric, was then used to observe its effect on this process. We found that in vitro B-cell immortalization with EBV was promoted by the oxidative stress induced by cyclosporine A and hydrogen peroxide, with the maximum effect seen at concentrations of 500 ng/ml and 100 microM, respectively. Curcumin blocked the B-cell immortalization in a dose-dependent fashion with nearly complete inhibition at 20 microM. We conclude that, because both hydrogen peroxide and cyclosporine A strongly promote in vitro B-cell immortalization with EBV (the putative process responsible for PTLD) and curcumin, an extract of a common spice is an effective inhibitor of this process; curcumin may be an effective adjunct in the prevention of PTLD in the patients undergoing therapy with cyclosporine A.     

Relation between insulin-like growth factor-I concentrations, osteoarthritis, bone density, and fractures in the general population: the Chingford study

OBJECTIVE: To assess the association between serum insulin-like growth factor-I (IGF-1) concentrations and osteoarthritis, and bone mineral density, and fractures in a large group of middle aged women from the general population. METHODS: 761 women aged 44-64 years from the Chingford study had serum IGF-I concentrations measured; hand, hip, spine, and anteroposterior weight bearing knee radiographs taken; and dual energy x ray absorptiometry (DEXA) scans of the hip and spine. X rays were scored using the Kellgren and Lawrence system. In addition knee x rays were scored using a standard atlas for individual features of osteophytes and joint space narrowing (both graded 0-3). IGF-I concentrations were adjusted for the effects of age. RESULTS: In the osteoarthritis analysis results were compared to a constant group of 155 subjects with no evidence of osteoarthritis at any site. There was no significant difference in serum IGF-I between these subjects and 606 subjects with osteoarthritis at any site. When individual sites were analysed, serum IGF-I was higher in those cases with more severe bilateral knee osteoarthritis and in those with distal interphalangeal (DIP) joint disease. There was no significant association between serum IGF-I and other forms of osteoarthritis or milder forms of knee osteoarthritis. There was no correlation between IGF-I concentrations and bone mineral density at the spine or hip, nor any difference between IGF-I concentrations in subjects with and without a history of non-traumatic fracture [22.8 (SD 6.6) v 23.1 (SD 6.6) nmol litre-1, P = 0.6] CONCLUSIONS: There is a modest association between IGF-I concentrations and the development of DIP osteoarthritis and more severe or bilateral knee joint osteoarthritis in women from the normal population, but no association with other forms of osteoarthritis, bone density, or fractures.     

CAG repeat expansion in autosomal dominant familial spastic paraparesis: novel expansion in a subset of patients

Autosomal dominant familial spastic paraplegia (FSP) is a genetically heterogeneous neurodegenerative disorder displaying anticipation for which three loci have been mapped to the chromosomal positions 14q11.2-q24.3 (SPG3), 2p21-p24 (SPG4) and 15q11.1 (SPG6). The repeat expansion detection (RED) method has been used to demonstrate expanded CAG repeats in some FSP families that map to SPG4. We analyzed 20 FSP families, including four for which there is evidence for linkage to SPG4, and found that in most cases the repeat expansion detected by RED is due to non-pathogenic expansions of the chromosome 18q21.1 SEF2-1 or 17q21.3 ERDA1 locus. Polymorphic expansions at SEF2-1 and ERDA1 appear frequent and may confound RED studies in the search for genes causing disorders demonstrating anticipation. In six FSP families, however, CAG repeat expansion was detected in a subset of affected and at-risk individuals that did not result from expansion of the SEF2-1 and ERDA1 loci. Overall, 11 of 37 (30%) of the FSP patients with a CAG/CTG repeat expansion are unaccounted for by the SEF2-1 and ERDA1 loci, compared with two of 23 (9%) of the unaffected at-risk individuals and none of 19 controls. In the majority of cases these novel expansions were shorter than those previously reported.     

Opsin localization and rhodopsin photochemistry in a transgenic mouse model of retinitis pigmentosa

In budding yeast, a protein kinase called Gin4 is specifically activated during mitosis and functions in a pathway initiated by the Clb2 cyclin to control bud growth. We have used genetics and biochemistry to identify additional proteins that function with Gin4 in this pathway, and both of these approaches have identified members of the septin family. Loss of septin function produces a phenotype that is very similar to the phenotype caused by loss of Gin4 function, and the septins are required early in mitosis to activate Gin4 kinase activity. Furthermore, septin mutants display a prolonged mitotic delay at the short spindle stage, consistent with a role for the septins in the control of mitotic events. Members of the septin family bind directly to Gin4, demonstrating that the functions of Gin4 and the septins must be closely linked within the cell. These results demonstrate that the septins in budding yeast play an integral role in the mitosis-specific regulation of the Gin4 kinase and that they carry out functions early in mitosis.     

Specific detection of the genus Serpulina, S. hyodysenteriae and S. pilosicoliin porcine intestines by fluorescent rRNA in situ hybridization

PURPOSE: Our purpose was to evaluate the utility of spectral imaging for multicolor, multichromosome enumeration in human interphase cell nuclei. METHODS: Chromosome-specific probes labeled with different fluorochromes or nonfluorescent haptens were obtained commercially or prepared in-house. Metaphase spreads, interphase lymphocytes, or blastomeres cells were hybridized with either 7 or 11 distinctly different probes. Following 46 hr of hybridization, slides were washed and detected using either a filter-based quantitative image processing system (QUIPS) developed in-house or a commercial spectral imaging system. RESULTS: The filter-based fluorescence microscope system is preferred for simultaneous detection of up to seven chromosome targets because of its high sensitivity and speed. However, this approach may not be applicable to interphase cells when 11 or more targets need to be discriminated. Interferometer-based spectral imaging with a spectral resolution of approximately 10 nm allows labeling of chromosome-specific DNA probes with fluorochromes having greatly overlapping emission spectra. This leads to increases in the number of fluorochromes or fluorochrome combinations available to score unambiguously chromosomes in interphase nuclei. CONCLUSIONS: Spectral imaging provides a significant improvement over conventional filter-based microscope systems for enumeration of multiple chromosomes in interphase nuclei, although further technical development is necessary in its application to embryonic blastomeres. When applied to preconception/preimplantation genetic diagnosis, presently available probes for spectral imaging are expected to detect abnormalities responsible for 70-80% of spontaneous abortions caused by chromosomal trisomies.     

Endoscopic hemostasis in bleeding gastroduodenal ulcer--a contribution to the cost aspect

Endoscopic injections of fibrin glue for the treatment of gastroduodenal ulcer hemorrhage have been increasingly used instead of sclerosing agents since 1987. Sclerosants have the drawback that they themselves have tissue-destroying or rather ulcerogenic effects. A difficult form of administration and a relatively high price are set against the good biological properties of the fibrin glue. In a randomized study comparing fibrin glue with polidocanol there was a statistically significant lower rebleeding rate in the fibrin group. The data of this study were analysed with regard to economic aspects. They showed an improved cost-benefit and cost-effectiveness ratio of the fibrin glue compared with polidocanol.