Immunophenotypic and genotypic markers of follicular center cell neoplasia in diffuse large B-cell lymphomas.

Diffuse large B-cell lymphomas (DLBCL) are a biologically and clinically heterogeneous entity. Although some DLBCL represent transformation of follicular lymphomas (FL), the proportion that is of follicular center cell (FCC) origin remains uncertain. Immunophenotypic and genotypic markers used to suggest a FCC origin for a lymphoma (bcl-6 and CD10 expression, lack of CD138 expression, bcl-2 rearrangements [R]) or to subdivide DLBCL (bcl-2 expression, bcl-6 R) were therefore investigated in 22 FL and 44 DLBCL using paraffin section immunostains and Southern blot/polymerase chain reaction analysis. All FL tested were bcl-6+ (19) and CD138- (22) with 16/19 also bcl-2 and CD10+ (classic phenotype), one bcl2+, CD10- (grade III) and two bcl2-, CD10+ (grade II or III). Bcl-2R was identified in 4/5 FL-GrI, 3/6 FL-GrII, and 1/3 FL-GrIII. Bcl-6R was found in 0/5, 2/4, and 0/3 FL, respectively. All but 3/41 DLBCL were bcl-6+ with 17/37 also bcl-2+ and CD10+. Three of these cases were also CD138+. Twelve bcl-6+ cases were bcl-2+, CD10-, six bcl-2-, CD10+, and two bcl-2-, CD10-. The three bcl-6- cases were bcl-2+, CD138- and two were CD10+. Bcl-2R was identified in 5/27 DLBCL with 4/5 bcl-2+, 3/4 tested CD10+ and 4/4 bcl-6+. Bcl-6R was identified in 7/26 including three with a classic FL phenotype. The vast majority of DLBCL in this study have an immunophenotype that supports a FCC origin. Although the proportion of DLBCL that co-expressed bcl-6, CD10 and bcl-2 was lower than for the FL, absence of bcl-2 or CD10 may be associated with higher grade FL It is also possible that bcl-6 expression is not completely specific for a FCC origin. Only a minority of cases suggested postfollicular differentiation. Only a minority of DLBCL show bcl-2R, suggesting that many have a different molecular pathogenesis than most low-grade FL. Bcl-6R did not exclude a FCC origin.

Pain sensitivity and individual differences in self-reported sexual behavior.

The relationship between sexual behavior and pain sensitivity was assessed in 27 heterosexual men and 20 heterosexual women. Sexual behavior measures included sexual motivation and ratings of subjective sexual arousal to and enjoyment of an auditory stimulus. Pain sensitivity measures were pain threshold and pain tolerance in a cold pressor task. Participants were tested after exposure to a neutral or a sexual audio stimulus. Exposure to the sexual stimulus increased pain sensitivity in women but not in men. However, sexual behavior measures were correlated with pain threshold for both men and women. Specifically, higher pain thresholds were associated with weaker sexual motivation, lower enjoyment potential for sexual interaction, and increased inhibition during intercourse. These results are consistent with findings in laboratory animals, suggesting that differences in sexual behavior may reflect differences in responsiveness to a variety of stimuli.

The Sexual Desire Inventory as a measure of sexual motivation in college students.

The human sexual response consists of at least two phases of behavior, the motivational phase and the consummatory phase, which are difficult to isolate. Sexual motivation questionnaires commonly contain items that assume sexual intercourse or partners' experience and are often difficult to use with sexually inexperienced persons. The Sexual Desire Inventory by Spector, Carey, and Steinberg does not appear to be confounded with consummatory behavior. Our goal was to check whether it can be used to measure sexual motivation. 40 men and 63 women completed the Sexual Experience Scale of sexual motivation by Frenken and Vennix and the Sexual Desire Inventory. Scores on the two inventories were highly correlated with this measure of sexual motivation and may be used with sexually inexperienced individuals.

Affective properties of intra-medial preoptic area injections of testosterone in male rats.

On alternating days, adult male Long-Evans rats implanted with unilateral cannulae in the medial preoptic area (MPOA) received intracerebral injections of testosterone (0.05, 0.1 or 0.2 microg/0.5 microl), or saline immediately prior to confinement for 30 min to one of two compartments of a place preference apparatus. All rats received 8 days of pairings (4 hormone and 4 saline). On day 9, the rats were given a hormone-free 20-min test session during which they had access to all compartments of the apparatus. Intra-MPOA injections of testosterone (0.1 microg) produced a conditioned place preference, while injections of a higher dose (0.2 microg) produced a conditioned place aversion. The rewarding effects of intra-MPOA testosterone may in part mediate the facilatory effects of testosterone on motivational aspects of sexual behavior.

A healthcare staff decision model considering the effects of staff cross-training.

In this study a staff planning model for a health service clinic has been developed and validated using an example case of a health service clinic. The primary purpose of this research is to develop a representative staff planning model which balances the cost and benefits of staff task flexibility through cross-training for a healthcare facility. Additionally, legal requirements for task substitution in the healthcare industry have been considered in the model.

Experimental Issues in Coherent Quantum-State Manipulation of Trapped Atomic Ions.

Methods for, and limitations to, the generation of entangled states of trapped atomic ions are examined. As much as possible, state manipulations are described in terms of quantum logic operations since the conditional dynamics implicit in quantum logic is central to the creation of entanglement. Keeping with current interest, some experimental issues in the proposal for trappedion quantum computation by J. I. Cirac and P. Zoller (University of Innsbruck) are discussed. Several possible decoherence mechanisms are examined and what may be the more important of these are identified. Some potential applications for entangled states of trapped-ions which lie outside the immediate realm of quantum computation are also discussed.

Characteristics of ecto-ATPase of Xenopus oocytes and the inhibitory actions of suramin on ATP breakdown.

Ecto-ATPase activity of Xenopus oocytes was studied by measuring the production of inorganic phosphate (Pi) from the breakdown of extracellular ATP. Enzyme activity involved Ca2+/Mg(2+)-dependent and Ca2+/Mg(2+)-independent dephosphorylation of ATP. Ca2+/Mg(2+)-dependent ecto-ATPase was active over a limited range of 0.01-1.0 mM ATP, while Ca2+/Mg(2+)-independent ATPase activity was active over a range of 0.1-30 mM ATP. Total enzyme activity was insensitive to changes in buffer pH (pH 7.0-9.0), but increased in a relatively linear manner with: (1) time of reaction (0-90 min), (2) number of cells (1-20 oocytes), and (3) temperature (10-37 degrees C). Ecto-ATPase activity was unaffected by ouabain (100 microM), sodium azide (100 microM), and oligomycin (5 micrograms/ml) (as inhibitors of endo-ATPases) and beta-glycerophosphate (10 mM) and p-nitrophenyl phosphate (10 mM) (as inhibitors of non-specific alkaline phosphatase). Total ecto-ATPase activity was reduced significantly in defolliculated oocytes, suggesting that the enzyme was located mainly on the enveloping follicle cell layer. The range order of preferential substrates was: ATP>GTP, ITP, UTP, CTP, TTP, 2-methylthioATP>ADP, 2-methylthioADP, AMP>>alpha, beta-methylene ATP, beta, gamma-methylene ATP, in the presence of divalent ions (where G is guanosine, I is inosine, U is uridine, C is cytidine and T is ribosylthymine). The P2-purinoceptor antagonist suramin [8-(3-benzamido-4-methylbenzamido)napthalene-1,3,5-trisul phonic acid), 100 microM] significantly inhibited total ecto-ATPase activity; this inhibition was competitive for the Ca2+/Mg(2+)-dependent enzyme.(ABSTRACT TRUNCATED AT 250 WORDS)

Staining for Bcl-2 protein helps to distinguish benign from malignant lymphoid aggregates in bone marrow biopsies.

Lymphoid nodules in a bone marrow biopsy may be either benign or malignant. Morphological clues may help to differentiate the benign from the malignant nodules. However, it is sometimes difficult, if not impossible, to make this distinction, especially in patients with a known low-grade lymphocytic malignancy. This study was undertaken to determine whether staining bone marrow biopsies with an antibody to the bcl-2 protein might aid in making this differentiation. Using a monoclonal antibody to bcl-2, we stained 26 bone marrows with benign lymphoid aggregates, 19 with a follicular lymphoma, 10 with small lymphocytic lymphoma/chronic lymphocytic leukemia, three with other non-Hodgkin's lymphomas, and three with other miscellaneous hematopoietic lesions. Only one of the 26 benign lymphoid aggregates had moderate to intense staining with this antibody; in contrast, 79% of the follicular lymphomas stained positively. Eight of the 10 small lymphocytic lymphoma/chronic lymphocytic leukemia cases stained with moderate to intense intensity; the other two cases had weak staining. No consistent pattern was seen with the other six lesions. Based on this data, we conclude that lack of staining of small lymphoid aggregates within the bone marrow with the antibody to the bcl-2 protein is suggestive of a benign aggregate, whereas moderate to strong staining intensity is most consistent with a malignant process.