For the calibration of a compaction simulator for punch displacement measurements, the displacement of the punch must be related to the voltage output of a linear variable displacement transducer (LVDT) which is attached to the punch via its movable core, with correction for any deformation of the machine parts which are inherently incorporated in the LVDT readings. Contrary to common assumptions the relationship between the displacement of the movable core and the voltage output of the LVDTs used is not linear. Similarly, the deformation of the machine parts did not follow Hooke's law of linear elasticity but exhibited characteristics of nonlinear elasticity. The data demonstrate the need for careful validation of the calibration of a compaction simulator when accurate punch displacements are required.

A Pavlovian conditioning experiment was conducted to determine whether morphine (6 mg/kg, IP) could act as a conditioned stimulus (CS) when paired with an electric shock unconditioned stimulus (US), and later produce a conditioned suppression of drinking (CR) in water deprived rats. Seven groups were tested for conditioning after exposure to one of the following conditioning procedures: (1) morphine paired with shock; (2) morphine alone with no shock; (3) shock but no morphine; (4) no shock and no morphine; (5) morphine paired with vocalizations of shocked rats; (6) saline paired with shock; (7) saline alone with no shock. Groups 1 and 2 tested whether morphine could act as a CS. Groups 3 and 4 tested for sensitization. Group 5 tested whether exposure to the vocalizations of other rats could act as a US when paired with a morphine CS. Groups 6 and 7 tested whether cues associated with the injection procedure could act as a CS. Only subjects in group 1 showed conditioned suppression of drinking, when compared to control groups. Overall, the results indicate that morphine could act as a conditioned stimulus and that several of the more obvious possible sources of artifact did not significantly contribute to the CR that it produced.

As part of a follow-up study of now-adult offspring who originally participated in the Hawaii Family Study of Cognition (HFSC) from 1972 to 1976, 49 females and 46 males from 73 families of Caucasian ancestry and 63 females and 55 males from 92 families of Japanese ancestry were retested (average test-retest interval, 13 years) on the battery of cognitive abilities tests they took as adolescents. Age-corrected scale scores for verbal ability, spatial ability, perceptual speed, visual memory, and unrotated first principal component were calculated for the offspring's fathers and mothers, for their original HFSC testing, and for the retesting. Model-fitting procedures for a univariate model of familial transmission indicated significant differences in the parameters between the two racial/ethnic groups for all five cognitive abilities scales. These procedures also demonstrated no significant differences in familialities for offspring abilities in adolescence vs. mature adulthood across all five abilities scales and both racial/ethnic groups.

Although numerous studies in rats have demonstrated an influence of serotonin (5-HT) on male copulation, no studies have yet to demonstrate whether such a relationship exists in primate species. The present study sought to characterize 5-HT influences on male copulatory behavior of rhesus monkeys by using three different 5-HT agonists: a full 5-HT_1A agonist, 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT); a partial 5-HT_1A agonist, ipsapirone; and a 5-HT_1C/1D agonist, m-chlorophenylpiperazine (m-CPP). 8-OH-DPAT had a biphasic effect upon ejaculation latency, with low doses (5–10 µg/kg) producing a shortening of ejaculation latency (time from initiation of copulation to ejaculation), and the highest dose (100 µg/kg) producing a lengthening of ejaculation latency. Intromission frequency (number of intromissions preceding ejaculation) was affected only at 10 µg/kg 8-OH-DPAT with monkeys requiring fewer intromissions to ejaculation at this dose. Ipsapirone administration led to a shortening of ejaculation latency at all doses tested (50–800 µg/kg), and a reduction in intromission frequency at 200–800 µg/kg ipsapirone. Administration of the 5-HT_1C/1D agonist, m-CPP, resulted in an increase in ejaculation latency at 200–400 µg/kg m-CPP and mount latency at 400 µg/kg m-CPP, but did not affect intromission frequency. In summary, stimulation of 5-HT_1A receptors lowered the ejaculatory threshold of the monkeys, while stimulation of 5-HT_1C/1D receptors interfered with copulatory behavior and raised the ejaculatory threshold. These results provide evidence that copulatory behavior of rhesus monkeys is influenced by 5-HT receptor stimulation, however, the direction of the effect depends upon the subtype of 5-HT receptor being stimulated.

In a series of ten patients affected by DiGeorge syndrome, we screened, by high resolution banding and fluorescent in situ hybridization of a cosmid probe, for microdeletions associated with this syndrome. In the ten patients, a microdeletion was demonstrated by in situ hybridization, but suspected only in two patients by high resolution banding.

Using degenerate primers based on published β₂-microglobulin sequences we were able to obtain an expected 111 base pairs (bp) polymerase chain reaction (PCR) fragment from tilapia genomic DNA. The sequence of this fragment showed a high degree of similarity to mouse β₂-microglobulin at the protein level. We used these primers in an “anchored PCR” to obtain a 213 bp PCR fragment from a carp cDNA library. This was then used to clone a full-length β₂-microglobulin cDNA from carp. The carp sequence showed the highest similarity to rabbit β₂-microglobulin. Both sequences showed strong similarities to all previously published vertebrate β₂-microglobulin sequences. The predicted protein secondary structure of both the carp and tilapia clones was almost identical to the corresponding regions of previously known vertebrate β₂-microglobulin protein sequences. When either the carp or tilapia probes were used against corresponding northern blots, they hybridized to a message of approximately 800–1000 bases long, which corresponds to the previously published lengths of β₂-microglobulin mRNAs. Southern blotting indicated that β₂-microglobulin was encoded by a single copy gene in both cases. Phylogenetic analysis indicated that the sequences were related to the β₂-microglobulins of higher vertebrates but grouped together in an ancestral position.

Many hormones, neurotransmitters, and growth factors produce their effects by inducing the hydrolysis of phosphatidylinositol 4,5-bisphosphate (PtdInsP₂) in the plasma membranes of their target cells by activating a phospholipase C. This produces myoinositol 1,4,5-trisphosphate (InsP₃), which releases Ca²⁺ from intracellular stores, and 1,2-diacylglycerol (DAG), which activates protein kinase C (Berridge 1987). There are two basic mechanisms by which agonists activate PtdInsP₂ hydrolysis. In the case of growth factors, the tyrosine kinase activity of their receptors phosphorylates and activates the γ isozymes of phosphoinositide phospholipase C (Meldrum et al. 1991; Rhee and Choi 1992). In the case of hormones, neurotransmitters, and certain other agonists, G-proteins transduce the signal from the receptor to phospholipase C β isozymes.