Relation between levels of circulating ovarian steroids and pituitary gonadotropin content during the menstrual cycle of the rhesus monkey

Anterior pituitary glands were removed from 27 intact cycling rhesus monkeys sacrificed in the early (Day 2), mid (Days 6--9) and late (Days 11--12) follicular phase, and in the early and late luteal phase (3--5 and 10--15 days after the midcycle luteinizing hormone (LH) surge). Assignment of cycle stage was confirmed by the pattern of circulating steroid and gonadotropin levels seen in the blood samples taken daily throughout the cycle. The anterior pituitary glands were weighed, stored at -30 degrees C and assayed for LH and follicle-stimulating hormone (FSH) content by specific radioimmunoassays. Serum estradiol levels and pituitary LH and FSH contents rose simultaneously during the follicular phase. After the preovulatory gonadotropin surge, pituitary LH content was low and invariant. Pituitary FSH content reached a nadir in the early luteal phase and tended to rise in the late luteal phase. Multiple correlation analyses revealed that there is a positive correlation between rising levels of estradiol in the circulation and pituitary LH (p = 0.003) and FSH (p = 0.017) content, and that there is a significant negative correlation between circulating progesterone levels and pituitary FSH content (p = 0.002). Pituitary LH content is less strongly related to circulating progesterone levels. There was no significant difference in the wet weights of the anterior pituitary glands during the five phases of the menstrual cycle studied.     

Variables influencing the origins of diverse abnormal behaviors in a large sample of captive chimpanzees (Pan troglodytes)

The developmental origin of abnormal behaviors is generally associated with early rearing environments that lack sufficient physical and sensory stimulation. However, other factors should also be considered. A large sample of captive chimpanzees (128 males and 140 females) was surveyed for the presence or absence of 18 abnormal behaviors. Origin variables included the subject's source (zoo, pet, performer, or laboratory), rearing (mother‐ or hand‐reared), and sex. Animals were assessed while held at the Primate Foundation of Arizona, University of Texas M. D. Anderson Cancer Center, or White Sands Research Center. There was a confound among origin variables; more hand‐reared animals than expected were from laboratories. Logistic regression tested the relationship of rearing and source, with sex as a secondary predictor variable, to each of the abnormal behaviors. There was no clear association between any abnormal behavior and source. However, for coprophagy, relative to animals from the laboratory, zoo animals tended to show a higher prevalence, while performers tended to show a lower prevalence (when rearing and sex were controlled). Rocking and self‐sucking were significantly more likely in hand‐reared animals. Coprophagy and depilation of self were significantly more likely in mother‐reared animals. When rearing and source were statistically controlled, the only significant sex difference was a higher prevalence of coprophagy in females and a higher prevalence of rocking in males. In a second, smaller sample of 25 males and 33 females from Southwest Foundation for Biomedical Research, no significant sex association was found for coprophagy, urophagy, rocking, or self‐depilation. In this second sample, coprophagy was also significantly more likely in mother‐reared than hand‐reared subjects. The association of some abnormal behaviors with mother‐rearing suggests that some form of social learning may be involved in the origin of some of these behavior patterns. This indicates that some abnormal behaviors may not be always be indicative of reduced psychological well‐being in captive chimpanzees. Am. J. Primatol. 48:15–29, 1999. © 1999 Wiley‐Liss, Inc.     

Weight gain in captive chimpanzee infants: Comparisons by sex,rearing, and colony

Weight gain has been monitored for 13 years in a mixed longitudinal study of captive chimpanzee growth and development. This report presents results of a comparative analysis of weight relative to age in 175 animals during the first 24 months in four sex/rearing groups (hand-reared females, hand-reared males, mother-reared females, and mother-reared males) from three colonies with different physical, nutritional, and social environments (Primate Foundation of Arizona, University of Texas M.D. Anderson Cancer Center Department of Veterinary Resources, Bastrop, TX, and White Sands Research Center, Alamagordo, NM). The Lowess method is used to generate fits of weight vs. age for each group and colony, with which individual animals at these and other colonies may be compared for assessment of developmental status. Comparisons of the curves, using the jackknife approach, show that there are significant differences between the curves, indicating that rearing and environmental parameters may be factors in weight gain rate and must be considered in such an assessment. Rearing effects may be the dominant of these factors in weight gain. © 1996 Wiley-Liss, Inc.     

Enantiomeric perylene-glycerolipids as fluorogenic substrates for a dual wavelength assay of lipase activity and stereoselectivity

A new type of fluorogenic alkyldiacyl glycerols was synthesized and used as fluorogenic substrates for the analysis of lipase activities and stereoselectivities. These compounds contain perylene as a fluorophore and the trinitrophenylamino (TNP) residue as a quencher. Both substituents are covalently bound to the ω-ends of the sn-2 and sn-1(3) acyl chains, respectively. Upon glycerolipid hydrolysis, the residues are separated from each other thus allowing determination of lipase activity by the continuous increase in fluorescence intensity which is caused by dequenching. Using enantiomeric pairs of these compounds, we were able to analyze lipase stereoselectivity depending on the reaction medium. Mixtures of enantiomeric fluorogenic alkyldiacyl glycerols, selectively labelled with pyrene or perylene as fluorophores, can be used for a dual-wavelength “stereoassay” of lipases. Since absorption and emission maxima of both labels are clearly separated, hydrolysis of the respective enantiomeric substrates can be determined simultaneously, and the difference in the rates of hydrolysis can be taken as a parameter for the stereopreference of a lipase. Hydrolysis rates measured with perylene-substituted lipids are generally lower than those obtained with the pyrene analogs. Thus, with a mixture of perylene and pyrene-substituted lipids, we observe a higher apparent stereoselectivity of lipases since we measure a combination of stereo- and substrate selectivity. In the presence of albumin, all microbial lipases tested so far exhibit stereopreference for the sn-1 glycerol position. In our assay, the apparent stereoselectivities are highest if in the presence of albumin, the sn-1 position carries pyrene and the sn-3 position is substituted with perylene. The lipase stereoselectivity assay described here requires the simultaneous measurement of the fluorescence intensities at two different wavelengths in a single cuvette and can thus be carried out using existing and cheap instrumentation that was developed for the fluorimetric analysis of Ca⁺⁺ concentrations. © 1996 Wiley-Liss, Inc.     

Preclinical investigations of the safety, immunogenicity and efficacy of a purified, inactivated tick-borne encephalitis vaccine

A new tick-borne encephalitis (TBE) vaccine for human use has been developed. TBE virus (TBEV) was propagated in primary chick embryo cells, inactivated by formalin and purified by continuous-flow density gradient centrifugation. The TBE vaccine was tested for innocuity, immunogenicity and protective capacity in a series of laboratory tests. The results indicated that the vaccine is outstandingly well tolerated, highly immunogenic in various laboratory animals, and induces protective immunity in mice. These data suggest that this new vaccine should be studied in clinical trials.     

Parasites and T helper cell development: some insights

Five years after the initial observations implicating the T helper (Th)-cell dichotomy (Th1/Th2) as the focal point in the immunoregulation of murine infection with Leishmania major, investigation has shifted to the factors that govern the differentiation of a specific immune response from its pre-immune of undifferentiated state. In this article, Steven Reiner focuses on the most recent advances concerning the lineage commitment of mature Th-cell populations, showing how new techniques [such as polymerase chain reaction (PCR) and transgenic mice] have allowed for a more-careful dissection of the early evolution of an immune response.     

Acetylene degradation by new isolates of aerobic bacteria and comparison of acetylene hydratase enzymes

Aerobic acetylene-degrading bacteria were isolated from soil samples. Two isolates were assigned to the species Rhodococcus opacus, two others to Rhodococcus ruber and Gordona sp. They were compared with known strains of aerobic acetylene-, cyanide-, or nitrile-utilizing bacteria. The acetylene hydratases of R. opacus could be measured in cell-free extracts only in the presence of a strong reductant like titanium(III) citrate. Expression of these enzymes was molybdenum-dependent. Acetylene hydratases in cell-free extracts of R. ruber and Gordona spp. did not require addition of reductants. No cross-reactivity could be found between cell-free extracts of any of these aerobic isolates and antibodies raised against the acetylene hydratase of the strictly anaerobic fermenting bacterium Pelobacter acetylenicus. These results show that acetylene hydratases are a biochemically heterogeneous group of enzymes.