Advancement of multiple myeloma from diagnosis through plateau phase to progression does not involve a new B-cell clone: evidence from the Ig heavy chain gene

The Ig heavy chain (IgH) gene was used as a marker to investigate clonal succession and the origin of the neoplastic cell in multiple myeloma. The polymerase chain reaction (PCR) was used to amplify a section of the rearranged IgH gene at diagnosis and at progression in 21 patients who had exhibited a plateau phase. A monoclonal PCR product was seen for 16 of the patients and the product present at progression was of the same molecular weight as that at diagnosis. This finding suggests that the IgH rearrangement present at diagnosis and progression was the same. This was confirmed by sequencing the IgH gene in 10 patients. The IgH genes were found to be hypermutated at diagnosis, but no further hypermutation occurred during the course of the disease. The results provide evidence that the neoplastic cell in myeloma may originate as a memory B cell, plasmablast, or plasma cell, and suggest that progression beyond the plateau phase is not caused by clonal succession.     

Heterogeneity of breakpoints of 11q23 rearrangements in hematologic malignancies identified with fluorescence in situ hybridization

Twenty-four patients whose cells contained a variety of 11q23 rearrangements, including translocations, insertions, and an inversion, were studied using fluorescence in situ hybridization with cosmid, phage, and plasmid probes mapped to 11q22-24. In 17 patients, the breakpoints of the common 11q23 translocations involving chromosomes 4, 6, 9, and 19 as well as some uncommon translocations involving 3q23, 17q25, 10p11, and an insertion 10;11 were all located in the breakpoint cluster region of the MLL gene, regardless of age, phenotype of disease, or involvement of a third chromosome. The breakpoints in 11q23 in the other 7 patients with a t(7;11)(p15;q23), inv(11)(p11q23), t(4;11)(q23;q23), der(5)t(5;11)(q13;q23), ins(10;11)(p11;q23q24), t(11;14)(q23;q11), or t(11;18;11) (p15;q21;q23) were located either centromeric to CD3D or telomeric to THY1. Thus, although most 11q23 rearrangements, involve the same breakpoint cluster region of MLL, there is heterogeneity in the breakpoint in some of the rare rearrangements.     

Digital and conventional chest images: observer performance with Film Digital Radiography System

The Film Digital Radiography System (FilmDRS) is a device with a laser optical film digitizer, 2,000 X 2,000 X 12-bit memory, and a 1,000-line video display. To evaluate the adequacy of this device for general radiography of the chest, four readers independently analyzed both radiographs and the corresponding video display of the digitized chest images of 150 patients, consisting of 100 images of abnormalities and 50 normal images. The overall results indicate equal sensitivity for the two systems. The FilmDRS, with interactive windowing, proved superior in the detection of hilar and mediastinal disease. X-ray film was superior in allowing detection of hyperlucent states. There was equivalent sensitivity for other disease categories. Superior specificity was achieved with conventional radiographs.     

Kinetics of intraocular cytokines in the suppression of experimental autoimmune uveoretinitis by type I IFN

The systemic administration of IFN-alpha/beta was previously found to suppress inflammation in rats with experimental autoimmune uveoretinitis (EAU); however, an effect on the systemic immune response was not identified. In order to investigate an immunological basis for suppression at the intraocular level, rats immunized with interphotoreceptor retinoid-binding protein (IRBP) were administered daily intramuscular injections of 10(5) IU IFN-alpha/beta and cytokines were measured by ELISA in intraocular extracts prepared by ultrasonification at various timepoints throughout the course of EAU. In control EAU, intraocular concentrations of IFN-gamma were found to be non-detectable on day 8 before the onset of inflammation, significantly elevated on day 12 at peak inflammation (182+/-106 pg/ml), then non-detectable again on day 16 after inflammation had begun to subside. In contrast, intraocular IFN-gamma in IFN-alpha/beta- treated rats remained non-detectable or low at all timepoints. Measurement of intraocular IL-2 revealed no difference between the two groups of rats. Intraocular IL-4 concentrations were elevated in rats treated with IFN-alpha/beta, although this cytokine was also detected in the same range in controls as well as normal rats. Finally, intraocular IL-10 was non-detectable on day 8, significantly elevated at peak inflammation on day 12 (588+/-139 pg/ml), then decreased to low levels on day 16 in control EAU rats, while remaining non-detectable or low in IFN-alpha/beta-treated rats. These results suggest that acute inflammation in IRBP-induced EAU in rats involves both IFN-gamma and IL- 10 at the local intraocular level, and that systemic administration of IFN-alpha/beta inhibits EAU via a mechanism that involves suppression of both cytokines.      

The upstream sequence element of the C2 complement poly(A) signal activates mRNA 3′ end formation by two distinct mechanisms

The poly(A) signal of the C2 complement gene is unusual in that it possesses an upstream sequence element (USE) required for full activity in vivo. We describe here in vitro experiments demonstrating that this USE enhances both the cleavage and poly(A) addition reactions. We also show that the C2 USE can be cross-linked efficiently to a 55-kD protein that we identify as the polypyrimidine tract-binding protein (PTB), implicated previously in modulation of pre-mRNA splicing. Mutation of the PTB-binding site significantly reduces the efficiency of the C2 poly(A) site both in vivo and in vitro. Furthermore, addition of PTB to reconstituted processing reactions enhances cleavage at the C2 poly(A) site, indicating that PTB has a direct role in recognition of this signal. The C2 USE, however, also increases the affinity of general polyadenylation factors independently for the C2 poly(A) signal as detected by enhanced binding of cleavage-stimulaton factor (CstF). Strikingly, this leads to a novel CstF-dependant enhancement of the poly(A) synthesis phase of the reaction. These studies both emphasize the interconnection between splicing and polyadenylation and indicate an unexpected flexibility in the organization of mammalian poly(A) sites.     

Histological characterization of a delayed wound healing model in pig

Chronic wounds, such as venous ulcers and pressure ulcers, frequently remain unresponsive to currently available treatments. Several animal models of wound healing have been published, including models of impaired healing developed to mimic the clinical condition of chronic wounds better. We used a delayed wound healing model in the pig that uses irradiation of the skin prior to creation of the surgical wounds and characterized it histologically. Radiation was used on one side of the back prior to making four full-thickness wounds on each side. Clinical observations were performed to record granulation tissue, reepithelialization, and wound area as a function of time. Histology data were obtained at 1, 2, 3, and 4 weeks, and slides were stained with hematoxylin and eosin for general observations. Immunohistochemistry was performed using laminin as a marker for blood vessels, and the number, size, and circularity of blood vessels found in the granulation tissue were measured. Our results show that this model causes a delay in wound healing that is mostly apparent between days 7 and 15. Granulation tissue took more time to form and fill the wounds on the irradiated side, and blood vessels were slower to develop. Blood vessels were larger and more irregular in shape on the irradiated side than on the control side. After 2 weeks, healing resumed, indicating that the induced damage was not irreversible. These results suggest that this model can be used to test the effects of therapeutic approaches intended to treat chronic wounds.     

The quality of interactions schedule (QUIS): Development,reliability and use in the evaluation of two domus units

The Quality of Interactions Schedule (QUIS) was developed as part of the prospective evaluation of two residential domus units for elderly people with severe mental illnesses. QUIS is an observational strategy in which social interactions between residents and care staff are coded as positive social, positive care, neutral, negative protective or negative restrictive. The interrater reliabilities of both the observational technique and the category codings were good. In the domus evaluation, QUIS demonstrated that the number and quality of interactions were significantly improved in both domuses compared to a baseline hospital ward at 3 months, 6 months and 12 months follow-up. In particular, the number of negative interactions observed fell to almost zero in the domuses at 12 months.