Construction of peptoliposomes for the incorporation of nutrient lipid supplements in insect cell culture media

Summary Nutrient liposomes that incorporate peptones instead of serum proteins can be used for the lipid supplementation of insect cells in lieu of or in addition to vertebrate serum to enhance the growth or differentiation of specific insect cell types in culture. The technique described here for the preparation of nutrient peptoliposomes involves the combination of both natural and synthetic phosphatidyl cholines (containing essential polyunsaturated fatty acids) with appropriate sterols. These are protected against premature oxidation by antioxidants (glutathione, alanine, protein hydrolysates) and antioxidant synergists (citrate, ascorbate, plus other amino acids) in the basal tissue culture medium as well as in the liposomal preparation itself (alphatocopherol acetate and protein hydrolysates). The lipid components are filter sterilized in chloroform and then dried before aqueous sonication, allowing the subsequent formation of a random array of unsized uni- and multilamellar liposomes, which are suitable as direct suppliers of lipid nutrients as well as nutrient carriers for lipid-soluble supplements.     

Fertilization and early embryology: Influence of maternal age on meiotic spindle assembly oocytes from naturally cycling women

To examine the effects of maternal ageing on the meiotic apparatus,we obtained oocytes from naturally cyding women in two age groups,including younger (aged 20–25 years) and older (aged 40–45years) women. Using high- resolution confocal microscopy weobtained a detailed picture of the meiotic spindle and chromosomeplacement during various phases of meiosls. Our data revealedthat the meiotic spindle in older women is frequently abnormal,both with regard to chromosome alignment and the micro- tubulematrix that comprise the meiotic spindle. The spindle in 79%of the oocytes from the older group exhibited abnormal tubulinplacement and one or more chromosomes were displaced from themetaphase plate during the second meiotic division. In contrast,only 17% of the oocytes from the younger age group exhibitedaneuploid conditions. The majority of eggs from this group possesseda well ordered, meiotlc spindle containing chromosomes thatwere fully aligned within a distinct metaphase plate in thespindle. Chromosome management during meiosis is directed bymicrotubule assembly within the spindle. These data suggestthat the regulatory mechanisms responsible for assembly of themeiotic spindle are significantly altered in older women, leadingto the high prevalence of aneuploidy.     

Affective and Behavioral Stress Outcomes in Alzheimer's Caregivers

Few investigations have looked at behavioral stress outcomes in Alzheimer's caregivers. This study documented concentration deficits to examine behavioral outcomes of stress in 33 Alzheimer's Disease (AD) caregivers and in 33 age-, sex-, and race-matched controls. As hypothesized, caregivers showed less persistence than controls in solving problems from a standard test of problem-solving ability. In addition, caregivers tended to make more errors than controls on a standard proofreading task ( p < .09). In AD caregivers, cognitive deficits (represented by lower scores on problem-solving and concentration tasks) may be representative of a broader deficit in concentration that impairs the ability of caregivers to provide for their own needs and the needs of the family member for whom they are caring.     

Role of monkey precentral cortex in control of voluntary jaw movements.

Monkeys were trained to produce a low, steady biting force for 0.5-2.5 s, and then a rapid forceful bite in response to a visual stimulus. After large bilateral lesions of the precentral face area, monkeys emitted repetitive forceful bites on the apparatus, but could not perform the force-holding task. They eventually relearned the task, but the force exerted was never as steady as it was prelesion, and often oscillated at about 2 and/or 5-6 Hz. After retraining, two animals with large bilateral lesions of the face area produced median RT responses equal to or only slightly longer than their prelesion performance, indicating that neural pathways not involving the precentral cortex can mediate quick visual RT responses. The variability of RTs was permanently increased, probably as a result of the persistent unsteadiness of the force-holding response. Incomplete bilateral lesions of the precentral face area, a complete unilateral lesion of that area, and bilateral lesions adjacent regions of cortex produced either mild, transient difficulties with the biting taks, or no problems at all. The results indicate that the precentral cortex has a role in the control of voluntary jaw movements. Lesions caused difficulty in controlling, but not producing, closing jaw movements, thereby suggesting that this role is predominantly to inhibit jaw-closing motoneurons or the systems that excite them. Electrical stimulation studies of the face area of the precentral cortex of the unanesthetized monkey point to the same conclusion.     

Painful palmar and plantar erythema associated with hepatic artery infusion of 5-fluoro-2'deoxyuridine

Painful palmar and plantar erythema is an uncommon systemic complication of chemotherapy and has been reported in association with methotrexate, cystosine arabinoside, doxorubicin, and 5-fluorouracil. The authors report a case in which the syndrome was precipitated by hepatic artery infusion of 5-FUdR. The previous recommendation that treatment of patients developing painful palmar-plantar erythema from other drugs may be successfully resumed using intrahepatic arterial infusion of FUdR must be reconsidered in light of the present report.     

Comparison of nasal pressure transducer and thermistor for detection of respiratory events during polysomnography in children

STUDY OBJECTIVES: The results of small studies have suggested that a nasal-cannula pressure transducer has a higher sensitivity than a thermistor in detecting hypopneas and diagnosing sleep-disordered breathing in both adults and children. We compared a thermistor alone, and in conjunction with a pressure transducer, for detection of sleep-disordered breathing in children during in-home polysomnography. DESIGN: Retrospective analysis of a subsample of a prospective cohort study. SETTING: Students attending elementary school in the Tucson Unified School District. PARTICIPANTS: A subsample of the Tucson Children's Assessment of Sleep Apnea study population. MEASUREMENTS AND RESULTS: Polysomnographic recordings of 40 children (24 girls and 16 boys, mean age 9.2 +/- 1.7 years; range 6-11 years) were analyzed to compare the detection of sleep-disordered breathing events by 2 different methods of measuring airflow: thermistor alone and thermistor with nasal-cannula pressure transducer (transducer) used simultaneously. The transducer detected all the respiratory events detected by the thermistor, but the thermistor detected only 84% of the transducer-defined events. Consequently, the transducer-derived mean respiratory disturbance index was higher than that detected by the thermistor (7.0 +/- 3.8 vs 5.9 +/- 3.4, P < .001). The bias error between transducer respiratory disturbance index and thermistor respiratory disturbance index on a Bland-Altman plot was 1.08 (95% confidence interval, 0.8 - 1.4). There was good agreement between the thermistor and the transducer for making the diagnosis of sleep apnea using a cutoff of a respiratory disturbance index greater than 5 (kappa = 0.69). The quality of the tracings with the transducer was comparable to that of the thermistor, but the transducer dislodged more frequently. CONCLUSION: The use of a nasal transducer in conjunction with a thermistor was more sensitive than the thermistor alone in detecting sleep-disordered breathing in children during unattended polysomnography.     

Abnormal courtship conditioning in males mutant for the RI regulatory subunit of Drosophila protein kinase A

The previously described site-selected P-element mutagenesis of a Drosophila gene encoding the regulatory subunit of cAMP-dependent protein kinase generates mutants that have defective behavior in the olfactory learning test. Here we describe the effect of the same mutations in a courtship conditioning assay. Wild-type males can distinguish between virgin females (which they court vigorously), and fertilized females (which they court less vigorously). After exposure to fertilized females, wild-type males modify their behavior by decreasing courtship to subsequent target virgins, an effect that may last for many hours. Like wild-type males, PKA-RI mutant males are also able to distinguish between virgin and fertilized females. PKA-RI males also modify their behavior towards virgin females after prior exposure to a fertilized female, but such an effect is short-lived, suggesting a defect in memory rather than learning. We also show that under these conditions the behavior of PKA-RI males is similar to that of amnesiac, dunce and rutabaga males.     

The effects of cortisol infusion upon hormone secretion from the anterior pituitary and subjective mood in depressive illness and in controls.

The aims of this study were to determine whether the administration of cortisol has a significant effect on mood in patients with depression and whether the effects of cortisol on changes in plasma hormone concentrations are like those of synthetic corticosteroids. Twelve patients had major depression and one each had dysthymic disorder and a depressive adjustment disorder. Five were male and nine were female. All were in-patients. Eight normal subjects, two females and six males, were used as controls. Basal beta-endorphin concentrations were 2- to 3-fold higher in depressed patients than in control subjects, but there were no significant differences between the patient and control groups in the basal (pre-infusion) plasma concentrations of ACTH, cortisol, growth hormone or prolactin. Cortisol, but not saline infusion resulted in a significant improvement in self rated mood. Surprisingly, cortisol infusion at first increased plasma beta-endorphin concentrations. At later times after cortisol infusion, plasma beta-endorphin concentrations decreased as did the plasma concentrations of ACTH and growth hormone; prolactin levels were increased. These results show (i) that cortisol infusion raises mood significantly in major depression, (ii) that plasma beta-endorphin concentration is a potential marker of major depression (iii) that rather than blunting of corticosteroid effects, responses to cortisol may even be enhanced in depressive illness. The unexpected, initial increase in beta-endorphin stimulated by cortisol, suggests that the action of cortisol is not simply one of negative feedback inhibition, but may involve mineralocorticoid, as well as glucocorticoid receptors.