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[Transferrin findings in Callithrix jacchus Linné, 1758 (Primates, Platyrrhina)].

This paper deals with the transferrin (Tf) polymorphism in the South American marmoset Callithrix jacchus. The transferrin bands of this species are positioned in the electropherogramme cathodal to the beta1C-globulin (C 3), s. Fig. 1. By means of the combined agarose gel immuno-electrophoresis 7 distinguishable phenotypes have been detected in 166 animals (s. Fig. 2). The formal genetic analysis of 28 matings with 48 youngs (cf. Table 1) leads to the assumption that at least 4 codominant alleles (Tf Cja, Tf Cjb, Tf Cjc, Tf Cjd) are existent at the autosomal Tf-locus in Callithrix jacchus.

Alleles

[Observations, analyses and experiments on the use of the hand in Callithrix jacchus Erxleben, 1777. Part II. Fine analysis of prehensive behavior].

The use of the hand of the common marmoset (Callithrix jacchus Erxleben, 1777) was analysed on the basis of observations and experiments conducted on 56 animals of all age. During arboreal locomotion Callithrix jacchus makes use of the hands for support and for grasping to maintain its balance, The palmar region serves as the main means of support, while the findgers in the locomotor grip also contribute to maintaining balance and support. The greater the need for maintaining balance, for example, during vertikal climbing or in movement along the narow branches, the mre complete the djustment of the hand form on the surface and the more complete the alignment of the hand on the branch will be. Additional support is supplied by the longitudinal palm furrow, caused by the radio-ulnar adduction of the hand edges and by the clinging properties of the volar pads...

Age Factors

A callosal projection of area 17 upon the border region of area MT in the marmoset monkey, Callithrix jacchus.

Injections of the retrograde tracer HRP into the border region of the temporal visual area MT and adjoining cortex in Callithrix labeled pyramidal neurons in area 17 of the contralateral hemisphere. Evidence is presented that this newly discovered heterotopic callosal projection of the monkey striate cortex connects regions of representation of the zero vertical meridian of the visual field in a retinotopic order.

Animals

Frequency representation in auditory cortex of the common marmoset (Callithrix jacchus jacchus).

The location and characteristics of the primary auditory cortex of the common marmoset, Callithrix jacchus jacchus, were determined in five anesthetized male adult animals by mapping the responses of cortical units and unit clusters to pure tone stimuli presented to the contralateral ear. The primary auditory cortex lies largely ventral to the lateral sulcus, the only major fissure on the lateral cortex of this smooth-brained primate, but in some animals it may extend significantly down the ventral bank of this sulcus. Responses are distributed such that low best frequencies are found rostroventrally whereas high best frequencies occur caudally. The disposition of frequency-band contours is fan-shaped, with contours separating low-frequency octaves nearly parallel to the lateral sulcus and high-frequency (greater than 8 kHz) contours perpendicular to that sulcus. Best frequencies range from 0.6 to 30 kHz across the primary field, but there is a disproportionate representation of the three octaves between 2 and 16 kHz. The most sensitive thresholds (as low as -2 dB SPL) are found between 7 and 9 kHz. The primary auditory cortex is similar in cytoarchitecture to that reported for the cat, showing a blurring of lamination in the middle layers (II-IV) and a preponderance of small cells in these merged layers, giving a highly granular appearance. The accessibility of the cochlear representation on the gyral surface makes the marmoset an attractive animal for studies of primate auditory cortex.

Animals

Postnatal development of dendrites of relay neurons in the lateral geniculate nucleus of the marmoset (Callithrix jacchus): a quantitative Golgi study.

Dendrites of multipolar relay neurons in the lateral geniculate nucleus of the marmoset (Callithrix jacchus), at various ages from birth to adulthood, were studied in rapid Golgi preparations. The dendrites were analyzed by means of three-dimensional computer reconstructions and decomposed into intermediate and terminal segments, both of which were further classified according to their centrifugal order. Measurements were made of the number of segments per dendrite, the total length of dendrites, and the mean length of intermediate and terminal segments. In adult marmosets, there are four stem dendrites on average per neuron, and each dendrite divides into a mean of 14 segments. Between birth and 6 weeks of age, the mean dendritic length doubles, mainly because of changes in terminal segments. There is a significant decrease in dendritic length into adulthood. The total number of stem dendrites does not change after birth, but during the first postnatal week dendrites lose distal segments, after which there is a significant increase in the number of segments of orders 3 to 7. The mean length of intermediate segments does not change with age, nor with order, whereas the length of terminal segments increases from 50 to 120 microns from birth to 6 weeks of age, and then decreases to the adult value of 80 microns. In conclusion, during the period of most rapid visual development, important morphological changes occur in geniculate relay-cell dendrites, involving essentially terminal segments. These observations correlate well with changes of geniculate volume and neuronal density.

Animals

Attenuated Junin virus infection in Callithrix jacchus.

Twenty marmosets, male Callithrix jacchus, were used during this study. Fifteen of the marmosets were inoculated with 5,000 TCID50 of the attenuated XJC13 strain of Junin virus by intramuscular route and five were left as uninoculated controls. Animals were observed for a 420-day period. In order to carry out virologic, hematologic, serologic, and histologic studies the animals were bled and/or killed at different days post infection(pi). Results obtained showed that the attenuated strain produced an infection with no mortality or signs of illness. There was only a slight loss of weight at 18-40 days pi, which was soon recovered. Viremia was present from day 6 to 22, titers peaking at 4.0 log. Viral spread was limited to the lungs, spleen, lymph nodes, and bone marrow in the animal killed on day 14. No virus was found in the organs of the animal killed on day 23, and neither hematologic alterations nor pathologic lesions were seen in these monkeys except for ganglionar hypertrophy with immunoblast proliferation. Antigen was detected by immunofluorescence (IF) in lymph nodes, spleen, adrenals, lungs and brain. Neutralizing antibodies were detected from the third week onward. Protection conferred by the XJC13 strain proved effective when XJC13-inoculated monkeys were challenged with 1,000 TCID50 of the pathogenic XJ strain at days 60 or 380 pi, while normal controls died. When viral persistence was searched for on days 370, 390, and 420 pi, no infectious virus was detected, but viral antigen was seen in certain organs, which, however, lacked tissue damage.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals

An ultrastructural study of early chorionic villus formation in the marmoset monkey (Callithrix jacchus).

The ultrastructural morphology of developing chorionic villi in the marmoset monkey (Callithrix jacchus) placenta was studied in pregnant monkeys at known time intervals after ovulation. In samples obtained at 45 days after ovulation the mesoderm, which consists of primitive foetal blood vessels, is seen to extend down into cytotrophoblast columns. Syncytiotrophoblast completely surrounds maternal blood vessels and both basal laminae and endothelial cells of maternal origin show signs of disorganisation and degradation. Syncytiotrophoblast is first observed to breach the maternal circulation in samples collected from animals at 60 days after ovulation; this results in discrete haemochorial villi randomly distributed throughout the placental bed. Samples obtained at 80 days after ovulation and term placental samples (145 days after ovulation) exhibit tertiary haemochorial villi throughout the placenta, similar to those seen randomly distributed at 60 days after ovulation.

Animals

The topology of the thalamo-cortical projections in the marmoset monkey (Callithrix jacchus).

This paper addresses the question of a general topological principle of thalamo-cortical projections. In the lissencephalic primate brain of the common marmoset (Callithrix jacchus), large injections of horseradish peroxidase were made in various parts of the neocortex. These injections were placed in different animals and hemispheres along various caudo-rostral and medio-lateral gradients. Labelled cells in the thalamus were plotted and the labelling-zones resulting from several injections along a medio-lateral and two caudo-rostral cortical vectors were drawn into semi-schematic thalamic maps. These composite maps reveal a topological organization of the whole thalamo-cortical projection. The thalamic representation of the caudo-rostral and medio-lateral gradients indicate a rotation of the posterior relative to the anterior thalamus. An attempt is made to relate the organization of the thalamo-cortical projection to the development of the thalamus and the cortex. The cortex is divided into concentric zones around the sensory-motor and insular cortex. The thalamus is divided into corresponding projection zones. The topology of thalamo-cortical connections can then be regarded as a consequence of corresponding thalamic and cortical growth gradients. This is not only consistent with the general thalamo-cortical topology and the inversion of maps from thalamus to cortex, but also explains the continuity and overlap of thalamic projection zones in the pulvinar to widely separated cortical areas as the parietal, temporal and frontal association cortex.

Animals

The basement membrane of the persisting maternal blood vessels in the placenta of Callithrix jacchus.

Formation and morphology of the thickened basement membrane-like layer around the persisting maternal vessels of the Callithrix jacchus placenta were investigated from day 45 until term (day 142) using light, electron and immunofluorescence microscopy. Thickening occurs with the establishment of contacts between the vessels and the syncytiotrophoblast (day 48). Final thickness is reached at about day 100. The course of the vessels shows wide gaps where the maternal blood flows freely into the intertrabecular spaces. As revealed by electron microscopy, the extracellular sheath around the maternal vessels consists of an inner subendothelial basement membrane (3-6 microns) and an outer fibril-containing layer (2-4 microns). Cell debris is seen between the two layers and in the basement membrane. Plaques of granular and fine-filamentous material are incorporated into the fibril-containing layer. The synthesis of the basement membrane material is localized in the endothelial cells. Immunofluorescence microscopy reveals collagen types IV and V, laminin and heparan sulfate proteoglycan (BM-1) in the sheath around the persisting vessels. Fibronectin occurs only in certain areas or in the form of dots. Collagen types I and III are not seen in the region of the vascular wall. It can, therefore, be assumed that the subendothelial layer represents a genuine basement membrane; the fibrils consist of collagen type V and the plaques contain fibronectin. The existence of the thick perivascular sheath is attributed to the persistence and stability of the maternal vessels.

Animals

The ultrastructure of early implantation in the marmoset monkey (Callithrix jacchus).

The ultrastructural morphology of the initial stages of implantation in the marmoset monkey (Callithrix jacchus) was studied in pregnant monkeys at known time intervals after ovulation. The earliest samples, obtained 13 days after ovulation, displayed both cytotrophoblast and syncytiotrophoblast. The cytotrophoblast was restricted to the blastocoel, whilst syncytiotrophoblast intruded to the endometrial basal lamina. At later stages, days 16 and 19 after ovulation, both cytotrophoblast and syncytiotrophoblast had extended laterally around the uterus, and the syncytiotrophoblast also extended deeper into the maternal tissues. The mesoderm layer was first discernible at 19 days after ovulation. At 23 days after ovulation the syncytiotrophoblast surrounded the maternal blood vessels entirely. In this study syncytiotrophoblast was not observed to breach the maternal blood vessels, even at 31 days after ovulation. Early cytotrophoblast columns could be seen at 31 days after ovulation. The endothelial cells lining the maternal blood vessels displayed hypertrophy from the earliest stages (day 13) onwards, although a true decidual response was only observed in samples of 23 and 31 days after ovulation.

Animals

Embryotoxic effects of thalidomide-derivatives in the non-human primate Callithrix jacchus. I. Effects of 3-(1,3-dihydro-1-oxo-2H-isoindol-2-yl)-2,6-dioxopiperidine (EM12) on skeletal development.

The response of pregnant marmosets (Callithrix jacchus) to the thalidomide derivative EM 12 was evaluated. EM 12 was selected for these studies because it is more active than thalidomide and is much more stable for hydrolysis. Skeletal gross structural abnormalities were observed when EM 12 was given to marmosets for 3-7 days during the period between days 49 and 60 post ovulation. Using the treatment schedule finally adapted in our laboratory, i.e. treatment during days 51-57 post ovulation, doses of 5 (or 10) mg EM 12/kg body wt induced the typical limb abnormalities known from man with an 80-100% certainty. In some animals we could observe the typical pattern of abnormalities even with doses as low as 1 mg EM 12/kg body wt. Abnormalities of the skeleton induced during this sensitive period are described. None of these (except some bifurcations of ribs) were seen in any of the ten litters (23 fetuses) serving as controls during the period of the study.

Abnormalities, Drug-Induced

Embryotoxic effects of thalidomide derivatives on the non-human primate Callithrix jacchus; 3. Teratogenic potency of the EM 12 enantiomers.

The teratogenic potencies of the enantiomers of 2-(2,6-dioxopiperidine-3-yl)-phthalimidine ( = EM 12), a teratogenic thalidomide analogue, were investigated in Callithrix jacchus, a primate very sensitive to the teratogenic action of this thalidomide analogue. The results indicate that the S-(-)-form of EM 12 is clearly more teratogenic than the R-(+)-form. The interpretation of the studies designed to evaluate stereo-selective differences in the teratogenicity of the enantiomers becomes difficult, since both enantiomers racemise in vivo with appreciable rates (Schmahl et al. 1988a, b). Therefore, it cannot be concluded as yet that the R-(+)-form lacks all teratogenic potential.

Abnormalities, Drug-Induced

Studies on the developmental cycle of Trichospirura leptostoma (Nematoda: Thelaziidae). Experimental infection of the intermediate hosts Blatella germanica and Supella longipalpa and the definitive host Callithrix jacchus and development in the intermediate hosts.

The cockroaches Blatella germanica and Supella longipalpa can act as intermediate hosts of Trichospirura leptostoma as demonstrated by experimental infestation. The parasite developed from the embryonated egg into the infective larval stage (L3) in cockroaches within 5-6 weeks. After experimental infection of marmosets (Callithrix jacchus), eggs were first found in faecal samples (prepatency) at 8-9 weeks post-infection. Patency lasts about 2 years. Despite the presence of living adult worms in the marmosets' pancreas, no additional eggs were observed in their faeces after the patent period.

Animals

Splitting of the circadian activity rhythm in common marmosets (Callithrix j. jacchus; primates).

Long-term recordings of the free-running circadian activity rhythm in common marmosets, Callithrix j. jacchus, living under constant environmental conditions (LL 200-470 lx) provided evidence of rhythm splitting in nonhuman primates. In two out of ten test animals two different types of splitting occurred; spontaneous persistent splitting and temporary splitting. Neither a reduction of the illumination intensity nor the application of dark pulses had any effect on the two activity components of the persistently split rhythm.

Activity Cycles

Polyhalogenated dibenzo-p-dioxins and dibenzofurans and the immune system. 1. Effects on peripheral lymphocyte subpopulations of a non-human primate (Callithrix jacchus) after treatment with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD).

Monoclonal antibodies were used to analyse the effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on peripheral lymphocytes from marmosets (Callithrix jacchus) following injections of single low doses of TCDD. A reduction of the percentage and the total number of lymphocytes among the white blood cells was seen 3 weeks after a single administration of 300 ng TCDD/kg body wt, but not following 167 ng TCDD/kg or less. After treatment of marmosets with the single subcutaneous dose of 10 ng TCDD/kg body wt. we observed an average decrease of about 20% in the percentage of CD4+ cells in the venous blood of treated animals. This change was not seen at the time of maximum absorption (2 weeks after the injection), but was demonstrable after 4 weeks and reached its maximum 15 weeks after the injection. The time course of the changes suggests an indirect effect (possibly via the thymus). Due to the considerable inter- and intra-individual variability in the number of peripheral lymphocytes the effect was less convincing on the basis of the total CD4+ cells per microliter blood. There was a significant concomitant increase in the percentage of cells with the CD8+ marker. A closer analysis of the lymphocyte subpopulation involved revealed a predominant effect on the cells with the CD4CDw29 ("leu 3a+4B4+") surface marker ("helper-inducer cells"). Subsequent to a dose of 10 ng TCDD/kg body wt the percentage of these cells was reduced by 50% or more when compared with the (24) controls. On an absolute basis (number of cell/microliter blood) these CD4+CDw29+ cells were clearly reduced in only two out of four marmosets. There was no significant effect on the percentage of the CD4+CD45R+ ("leu3a+2H4+") subpopulation ("suppressor-inducer cells"). The ratios: CD4+CDw29+/CD4+CD45R+, or CD4+CDw29+/CD8+ appear to be convenient measures for monitoring the effect described. Since the difference between the percentage of CD2+ cells minus the sum of CD4+ plus CD8+ cells was found to be increased following rather high doses (167 ng TCDD/kg body wt or more), this suggests that immature cells (CD2+ CD4-CD8-) are released into the periphery as a result of the exposure to TCDD. Furthermore, a decrease in the percentage of CD20+ (B1+) cells (about 50% when compared with controls) was observed in the treated animals following a single dose of 10 ng TCDD/kg body wt or higher. Subsequent to a dose of 10 ng TCDD/kg body wt the percentage of CD56+ (NKH1+) cells seemed to be slightly increased. The dose-response for the effects observed was rather poor.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals

[Radiotelemetric studies of the body temperature of white-tufted monkeys (Callithrix jacchus)].

A newly developed telemetry system was used to study deep body temperature (BT) of two adult male common marmosets (Callithrix jacchus). The BT-curves of both monkeys showed a similar clear circadian rhythm with a range up to 3.5 degrees C. At environmental temperature of 28 degrees C (ET) the BT of the monkeys varied in the daytime dependent on their spontaneous activity, with little individual differences between 37.5 degrees C and 39.3 degrees C; at night the BT of the remarkably deeply-sleeping animals decreased to an average at 35.8 degrees C. Elevating ET up to 30 degrees C effected an increase of BT by 0.6 degrees C, both during day and night. On the contrary, reducing ET to 24 degrees C the BT increased only at night, by 0.2 degrees C at ad libitum food intake and 1.0 degrees C at fasting. Measurements of BT by inserted rectal thermometer caused, compared with telemetry, an average at 0.4 degrees C higher values.

Animals

Polyhalogenated dibenzo-p-dioxins and dibenzofurans and the immune system. 4. Effects of multiple-dose treatment with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on peripheral lymphocyte subpopulations of a non-human primate (Callithrix jacchus).

Non-human primates (Callithrix jacchus) were treated with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) over a period of 30 weeks, and lymphocyte subpopulations of venous blood were monitored using monoclonal antibodies and flow cytometry (FACScan). There was no clear-cut change in the total lymphocyte population during this study. In the first part of the study the new-world monkeys (marmosets) were treated for 24 weeks with a weekly dose of 0.3 ng TCDD/kg body wt. At the end of this treatment period a level corresponding to an actual cumulative dose of about 2.5-2.7 ng TCDD/kg body wt was expected. The percentage and the absolute number of the CD4+CDw29+ cells ("helper inducer" or "memory" cells) surmounted the physiologically occurring increase. Concomitantly the percentage of the CD4+CD45RA+ cells ("suppressor-inducer" or "naive" cells) decreased. There was, at the same period, no change in the total T cell population (CD2+ cells) or in the cells carrying the CD8 or the CD4 epitope. When increasing the weekly dose to 1.5 ng TCDD/kg body wt, a transient increase in the percentage and the absolute number of the CD8+CD56+ cell population ("cytotoxic T cells") was observed 3 weeks after the increase in dosing. At this time the expected decrease in the percentage or the absolute number of CD4+CDw29+ cells was just detectable and this decline was at its maximum 6 weeks after switching to the higher weekly doses. The reduction in the percentage and the absolute number of CD4+CDw29+ cells persisted 5 weeks after discontinuation of the dosing, but this cell population was again within normal limits 7 weeks later. Because the two subpopulations are changed in opposite directions, the ratio CD4+CDw29+/CD4+CD45RA+ is a very sensitive measure of the effect induced by TCDD. There was a pronounced decrease in the percentage of the CD20+ cells (B1 cells), but their percentage and number rapidly normalized, in contrast to the CD4+CDw29+ cells, when the dosing was discontinued. At the end of the treatment period the apparent body burden was calculated to correspond to an actual dose of about 9-10 ng TCDD/kg body wt. Such an actual dose level might be assumed to be reached under steady-state conditions in chronic experiments with daily doses of about 135 pg TCDD/kg body wt (assuming a half-life for TCDD in the marmoset of 6-8 weeks). Extrapolations of the results obtained at higher doses to very low exposures is not justified with respect to the effects induced by TCDD on the immune system of marmosets. At lower doses the effect is clearly reversed.

Animals