Biological and clinical significance of cytogenetic abnormalities in low-risk and high-risk gastrointestinal stromal tumors

We report cytogenetic findings in 19 c-Kit-positive gastrointestinal stromal tumors (GISTs) that represent a heterogenous group of mesenchymal neoplasms with respect to site, histology, and biologic behavior. All of the GISTs (5 low-risk, 11 high-risk, 3 recurrences) displayed clonal chromosomal aberrations; 15 were hypo- to near-diploid, and 4 were near-triploid and hypotetraploid. The most common abnormalities were loss of chromosomes 14 and/or 22, demonstrated in 14 GISTs irrespective of site or predominant phenotype. Ten cases (2 low-risk, 5 high-risk, 3 recurrences) were characterized by loss of both chromosomes 14 and 22, 2 cases (1 low-risk, 1 high- risk), by loss of chromosome 14; and 2 high-risk cases, by loss of chromosome 22. Additional chromosomal aberrations occurred preferentially in high-risk and recurrent GISTs, including loss of 9p and 1p in 8 cases each, loss of 15 in 6 cases, loss of 3p in 5 cases, loss of 13q and 10q in 4 cases each, loss of 19 in 3 cases, and complete or partial gains of chromosomes 5 and 4 in 2 cases each. More significantly, 5 of 6 patients with clinically aggressive GISTs, including 2 recurrences and 3 metastasing GISTs, were additionally characterized by loss of 9p; four of these had additional loss of chromosomes 1p and 15. The presented results herein indicate that loss of chromosome 14 and/or 22 is an early change in GIST tumorigenesis irrespective of site or differentiation, whereas malignant transformation and progression of GISTs appear to be associated with an increasing incidence of additional secondary aberrations.     

Improvement of cytomegalovirus avidity testing by adjusting the concentration of CMV-specific IgG in test samples.

BACKGROUND: Human cytomegalovirus (CMV) is the most common cause of viral intrauterine infection. Primary CMV infection in early pregnancy bears a high risk of fetal damage. Accurate measurement of CMV-specific IgG avidity may help to improve the serodiagnosis of CMV-infected women by determining the time of infection and fetal outcome. OBJECTIVES: To study the performance of the CMV avidity assay with the fully automated Vidas analyzer (bioMérieux) as a function of the concentration of CMV-specific IgG present in the serum sample. STUDY DESIGN: Eighty-two serum samples were investigated from 3 clinical scenarios: 18 individuals with sera negative for CMV-specific IgG and IgM (control group), 20 pregnant women (44 samples) containing CMV-specific IgG- and IgM-antibodies suggesting acute or recent primary infection and 20 patients with evidence of past infection (CMV-IgG positive and CMV-IgM negative). RESULTS: In the group with presumed acute or recent primary infection 12 of 44 sera had CMV-specific IgG values above 100 arbitrary units (AU, bioMérieux)/ml and in these cases an increase in AI was measurable upon dilution of the serum sample. In two cases, AI's were shifted towards or above the cut-off value of AI>or=0.8, indicative of past infection. Dilution of sera which were CMV-specific IgM positive and had specific IgG concentrations of 相似文献   

Pharmakologisch-aktive polymere, 21. Orientierende Untersuchungen zur körperverteilung und Ausscheidung von poly[2-(methylsulfinyl)ethylacrylat]en bei der Ratte

Poly[2-(methylsulfinyl)ethyl acrylate] ( 1 ) was synthesized as well as derivatives ¹⁴C-labelled in side groups ( 6 ) or ¹⁴C-labelled in the main chain ( 11 ). Polymer 11 with the ¹⁴C-labelled main chain was fractionated by precipitation. The η-M-relation determined by measurements of unlabelled polymers in the ultracentrifuge for comparison was used to establish the viscosimetrically determined molecular weights of the labelled fractions. After intravenous application of aqueous solutions of the polymer in rats the excretion rate up to 72 h after treatment was ascertained to ca. 50%; the concentration in the blood serum was found to be strikingly high. A tendency to reinforced storage in organs of high phagocytose activity by growing molecular weight was observed. The tumor affinity was — if at all — low.     

Packing and Uniaxial Alignment of Liquid Crystalline Oligofluorenes

Summary: Liquid crystalline oligomers of 9,9‐bis(2‐ethylhexyl)fluorene of defined degree of polymerization 4, 5, 6, and 7 were investigated by X‐ray diffraction in the non‐oriented and in the aligned state. The diffraction data give evidence for a smectic B type phase for all of the oligomers. Quenching below the glass transition does not change the structure of the liquid crystalline phase. This allows to align spin‐coated films of these oligomers on rubbed polyimide substrates to give monodomain films. These are stable against thermal disordering below T_g, e.g. at room temperature. The degree of alignment is characterized by the dichroic spectra and polarized fluorescence spectra. Dichroic ratios and polarization ratios increase substantially with the chain length and values as high as D = 23 and P = 41 are obtained for the heptamer. The type of packing of the oligomers in the LC phase is discussed based on the X‐ray single crystal structure of models. In one such model the packing of the 2‐ethylhexyl side chains could be fully resolved, while the other model reveals the torsional angle between adjacent fluorene units in the same molecule as 144.2° which corroborates earlier work based on fiber diffraction of corresponding polyfluorenes.

     

Transmission of tuberculosis between men and pet birds: a case report

The present report describes a case of Mycobacterium tuberculosis infection in an African Grey parrot (Psittacus erithacus erithacus) kept as a pet bird. Diagnosis was confirmed by microbiologic and pathologic results, and indicated a human–avian transmission. Clinical signs included sublingual nodules resulting in anorexia and signs of osteolysis in the long bones. Proliferation consisted of several nodules with small greenish-caseous foci in cross-section and revealed a severe granulomatous inflammation without intralesional acid-fast rods. M. tuberculosis was cultured from a pooled sample of sublingual and liver nodules, and was confirmed via polymerase chain reaction. Transmission between men and parrot was proved by spoligotyping pattern analysis. The absence of facial skin lesions and acid-fast rods within the tubercles is contrary to previous publications of tuberculosis in birds. This disease in a common pet bird species is of zoonotic importance, and those parrots with close contact to owners suffering from tuberculosis may serve as a potential reservoir for human infection.     

Viral hemagglutinin augments peptide-specific cytotoxic T cell responses

In attempt to increase the induction of peptide-specific cytolytic T cells (CTL) we investigated the effect of the Newcastle disease virus (NDV) hemagglutinin-neuraminidase (HN) gene product on the activation of peptide-specific CTL. Spleen cells of CH3 mice immunized against the influenza nucleoprotein peptide 50–63 (NP 50–63) were restimulated in vitro (i) with peptide-pulsed syngeneic fibroblast cells (Ltk^?) as antigen-presenting cells, which were in addition (ii) infected with NDV or (iii) stably transfected with the HN cDN A of NDV. A greater than sixfold increase in peptide-specific CTL responses was observed in cultures restimulated with peptide-pulsed Ltk^? cells which co-expressed viral hemagglutinin due to either infection or transfection. A similar augmentation was seen in CTL responses against other types of antigen (major histocompatibility complex alloantigens, minor histocompatibility antigens or tumor antigens) when suboptimal cultures were stimulated with the respective antigen-presenting cells modified by NDV infection. These findings suggest that NDV or viral HN expressed on antigen-presenting cells or tumor cells can exert a T cell co-stimulatory function.     

Synthesis and properties of molecularly uniform oligourethanes with chain-folding units in the center

The study of a series of molecularly uniform poly(N-alkylurethanes) with a systematically varied and tailored chain architecture has shown that the packing and superstructure can be controlled by the primary structure of the urethane chain and reversibly altered by the sample treatment, respectively. Depending on the conformation or the stereogeometry of the constitutive unit built in the middle of the otherwise symmetrical oligourethane, chain-extended and/or chain-folded crystallization of the urethane chain can occur. The packing order, i. e., adjacent recentry chain-folding or chain-extended crystallization, and the thermal properties of the oligourethanes are related to the chemical structure of the central constitutive unit.