B cell terminal differentiation is associated with the onset of high-level antibody secretion and cell cycle arrest. Here the cyclin-dependent kinase (CDK) inhibitor p18
INK4c is shown to be required ...within B cells for both terminating cell proliferation and differentiation of functional plasma cells. In its absence, B cells hyperproliferate in germinal centers and extrafollicular foci in response to T-dependent antigens but serum antibody titers are severely reduced, despite unimpaired germinal center formation, class switch recombination, variable region-directed hypermutation, and differentiation to antibody-containing plasmacytoid cells. The novel link between cell cycle control and plasma cell differentiation may, at least in part, relate to p18
INK4c inhibition of CDK6. Cell cycle arrest mediated by p18
INK4C is therefore requisite for the generation of functional plasma cells.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Aim of the study was to assess cardiovascular effects in the farmers exposed to noise. We assessed two samples of 143 farmers using tactor (mean age 51.0 +/- 10.5 years, length of service 33.0 +/- ...10.5 years) and 193 farmers not exposed to noise (controls) (mean age 48.3 +/- 13.7 years, length of service 30.6 +/- 14.7 years). After the phonometric measurements all farmers were undergone to a medical examination, measurements of blood pressure, a audiometric test and a electrocardiogram. The collected data show an increased prevalence of hypertension and electrocardiographic anomalies in farmers exposed to noise (systolic hypertension n. 53, 37.1%; diastolic hypertension n. 60, 42.0%; electrocardiographic anomalies n. 44; 30.8%) compared to the control group (systolic hypertension n. 23, 16.1%; diastolic hypertension n. 26, 18.2%; electrocardiographic anomalies n. 5; 3.5%) (systolic hypertension p = 0.002; diastolic hypertension p = 0.003; electrocardiographic anomalies p = 0.030). Our results could be taken to mean that there are effects of chronic exposure to noise on cardiovascular apparatus; this would stimulate the screening programmes for farmers.
This paper describes the synthesis of novel derivatives
4a–i, which are structurally related to PD134308 and in which the indole moiety is replaced by other aromatic groups. Cholecystokinin-A and -B ...(CCK-A and CCK-B) receptor binding affinities of these analogues are described and the contribution of the various rings is discussed. Several of the compounds prepared have CCK-B receptor binding values similar to that reported for PD134308 and are highly selective over the CCK-A receptor. They represent potential therapeutic agents for anxiety.
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IJS, IMTLJ, KILJ, KISLJ, NUK, SBCE, SBJE, UL, UM, UPCLJ, UPUK
We have exploited a recently characterized system of rat thyroid epithelial cells transformed by the wild-type (wt) and a temperature-sensitive (ts) mutant strain of the Kirsten murine sarcoma virus ...(Ki-MSV) in order to study the effects of the K-ras oncogene on the gene expression of differentiated thyroid epithelial cells. By using cDNAs isolated from normal thyroid glands as probes, we were able to identify three sets of cellular sequences whose expression is influenced by the v-K-ras oncogene. The first set of genes is irreversibly repressed by transformation with both the wt and the ts viruses. The second set of genes is repressed in the ts-Ki-MSV-transformed cells but not in the same cells grown at the nonpermissive temperature. A third set of genes is present at higher levels at the nonpermissive temperature than at the permissive temperature. This system has allowed us to isolate and characterize a number of cDNA clones belonging to each of these three sets of genes. These specific cDNAs are suitable probes to study phenotypical changes during transformation of epithelial cells.
The synthesis of two "dipeptoids" structurally related to the CCK-B antagonist CI-988 (PD134308) is described. The 2- and 1-indolyl derivatives 4a, b were prepared in order to define the role of the ...tryptophan moiety in this series of "dipeptoids". They were evaluated as competitors in the binding of 3H-CCK8S on guinea pig brain CCK-B receptors.
Physical Review E 66, 021304, 2002 Aging behavior is an important effect in the friction properties of solid
surfaces. In this paper we investigate the temporal evolution of the static
properties of ...a granular medium by studying the aging over time of the maximum
stability angle of submillimetric glass beads. We report the effect of several
parameters on these aging properties, such as the wear on the beads, the stress
during the resting period, and the humidity content of the atmosphere. Aging
effects in an ethanol atmosphere are also studied. These experimental results
are discussed at the end of the paper.
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