Biomedical subjects
Publications and source records attributed to L Lyons.
Sheep, mice, cattle, goats and pigs have all been cloned by transfer of a donor cell nucleus into an enucleated ovum, and now we add the successful cloning of a cat (Felis domesticus) to this list. However, this cloning technology may not be readily extendable to other mammalian species if our understanding of their reproductive processes is limited or if there are species-specific obstacles.
The period (per) gene is an essential component of the circadian timekeeping mechanism in Drosophila. This gene is expressed in a circadian manner, giving rise to a protein that feeds-back to regulate its own transcription. A 69 bp clock regulatory sequence (CRS) has been identified previously upstream of the period gene. The CRS confers wild-type mRNA cycling when used to drive a lacZ reporter gene in transgenic flies. To determine whether the CRS also mediates proper developmental and spatial expression and behavioral rescue, we used the CRS to drive either lacZ or per in transgenic flies. The results show that the CRS is able to activate expression in pacemaker neuron precursors in larvae and essentially all tissues that normally express per in pupae and adults. The CRS is sufficient to rescue circadian feedback loop function and behavioral rhythms in per01 flies. However, the period of locomotor activity rhythms shortens if a stronger basal promoter is used. This study shows that regulatory elements sufficient for clock-dependent and tissue-specific per expression in larvae, pupae, and adults are present in the CRS and that the period of adult locomotor activity rhythms is dependent, in part, on the overall level of per transcripts.
Intrathecally applied alpha2-adrenoceptor antagonists atipamezole, idazoxan and yohimbine had no significant effect on any neuronal response in normal animals. In contrast, all three antagonists (100 microg) significantly increased the area under the curve of the total response to formalin, especially the second phase. Our results suggest the alpha2-adrenoceptor-mediated noradrenergic inhibitory system in the spinal cord is dormant under normal conditions, but controls both the magnitude and duration of the neuronal responses to subcutaneous injection of formalin.
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OBJECTIVE: The authors investigated the clinical feasibility and the outcome for patients of a program designed as an alternative to acute hospitalization. METHOD: This was a random-design study comparing a conventional inpatient program for urban, poor, severely ill voluntary patients who usually require hospitalization to an alternative experimental program consisting of a day hospital linked to a crisis residence. Patients were assessed with standardized measures of symptoms, functioning, social adjustment, quality of life, and satisfaction with clinical services upon admission to the study, at discharge from the index admission, and at follow-ups 2, 5, and 10 months after discharge. RESULTS: One hundred ninety-seven patients were enrolled in the 2-year research program and followed for 10 months. Of the voluntary patients who would have been admitted to the hospital, 83% were appropriate for the experimental program. The clinical, functional, social adjustment, quality of life, and satisfaction outcome measures were not statistically different for the patients in the two treatment conditions; however, there was a slightly more positive effect of the experimental program on measures of symptoms, overall functioning, and social functioning. CONCLUSIONS: The experimental condition, a combined day hospital/crisis respite community residence, seems to have had the same treatment effectiveness as acute hospital care for urban, poor, acutely ill voluntary patients with severe mental illness.
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Genetic variation in the C1R subcomponent of the first complement component C1 was investigated in U.S. whites by isoelectric focusing and immunoblotting. In addition to the previously described two alleles, the products of a new and rare third allele designated C1R*3 were detected. The expression of the new allele is consistent with autosomal codominant inheritance, which is confirmed by family data. The frequencies of the C1R*1, C1R*2 and C1R*3 alleles in 201 randomly selected U.S. whites are: 0.908, 0.090, and 0.002, respectively.
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Home monitoring for apnea patients has been called a stressful situation for family members. A 28-item questionnaire was used to ascertain the impact of home monitoring on the families of children with infantile apnea. Forty of 71 families returned the questionnaire. The majority of respondents felt the stress of home monitoring to be minimal (42.5%) to moderate (37.5%). All respondents favored home monitoring with 80% of parents reporting that the monitor had alerted them to at least one significant apnea or bradycardia episode during the first month of use. Half of parents reported more than five significant alarms in the first month of use. Financial hardship on the family was reported to be minimal. A few parents related significant strain on marital and other sibling-parent relationships. Concerns most commonly voiced were mechanical problems (70%), difficulty in locating qualified and willing babysitters (62.5%), and desire for more concrete information from the physician regarding the child's medical problem (40.0%). These results confirm good acceptance of home monitors by the family and offer direction in dealing with the families' primary concerns.
The effects of albumin on taurocholate uptake by rat basolateral liver plasma membrane vesicles were examined. With this system direct effects on carrier-mediated Na+-dependent bile acid uptake may be distinguished from nonspecific alterations in carrier-independent diffusion. Bovine serum albumin increased both the initial velocity and peak uptake of taurocholate in the presence of an Na+ gradient but did not enhance Na+-independent bile acid uptake. The effects of albumin were strikingly dependent on albumin concentration. Maximal enhancement of bile acid uptake was observed at albumin concentrations of 0.125 g/dl (18 microM) to 0.25 g/dl (37 microM), which are similar to reported values for the Kd for albumin binding to the plasma membrane. At high albumin concentrations (2.5 g/dl, 367 microM), uptake was reduced but to a lesser extent than the expected fall in free bile acid concentration. Kinetic studies showed that albumin (0.5 g/dl, 74 microM) reduced the taurocholate Km from 36.5 to 16.1 microM but did not affect Vmax, suggesting that albumin binding may increase the affinity of the bile acid receptor for taurocholate. Bovine gamma-globulin, chicken ovalbumin, and human transferrin did not enhance taurocholate uptake. Control experiments demonstrated that the mechanism of the albumin effect was not dependent on residual albumin-bound calcium and did not involve alteration of the underlying driving forces for bile acid uptake (Na+ gradient). These studies have "unmasked" an enhancing effect on taurocholate uptake by low concentrations of albumin that would not have been readily detected at higher concentrations.
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