Effects of brief separation from mother on rhesus monkeys

To summarize, data on the course of development of mother-infant relations in rhesus monkeys have been presented; a method for teasing apart the relative roles of mother and infant in causing changes or differences in the interaction described; and the complexity of the social nexus, within which the relationship is set, stressed. When the mother is removed for a few days, the infant calls a great deal at first and then shows depressed locomotor and play activity. These symptoms may last for a month after the mother's return. Simple tests given 6 months and even 2 years later strongly suggest that the differences (between infants that have had such a separation experience and infants that have not) are persistent. Are these data relevant to the human case? The rhesus monkey has no verbal language and a much less complex social development than man. Furthermore, its social environment is quite different from that found in any human culture. Parallels between monkey and man must therefore be scrutinized carefully before being used as a basis for generalization. But the facts show that a brief separation experience produces in rhesus monkey infants symptoms that are very similar (except for the apparent absence of a "phase of detachment" on reunion) to those in human infants (25). While age of separation, within the rather narrow limits used here, was a variable of minor importance, the effects of the separation varied, as in the human case, with the length of the separation experience and the sex of the infant. Differences in the techniques of experimenters, as well as differences in the species, prevent precise comparisons of the roles of the mother-infant relationships; nevertheless, the nature of the relationship appears to be an important variable in both monkey and man. There would seem, therefore, to be strong reasons for thinking that we are dealing with comparable phenomena. If that is the case, the fact that monkeys function at a simpler conceptual level than man limits the complexity of the explanatory hypotheses necessary in the human case. In addition, the finding that such a brief separation experience, involving removal of the mother but no exposure to a strange environment, can produce effects lasting for months or years in rhesus monkeys strengthens the evidence that long-term effects may occur also in man. Finally, this analysis provides bases for attempts to predict individual differences in the effects of a period of separation on rhesus infants, and the parallels with man suggest that examination of the same variables in the human case would be worthwhile.     

人工饲养猕猴产后瘫痪的防治

通过观察猕猴产后瘫痪的临床症状,并与类似疾病进行比较,做出诊断,最后提出预防和治疗措施,以期为猕猴产后瘫痪预防、治疗提供参考。     

Is face processing species-specific during the first year of life?

Between 6 and 10 months of age, the infant's ability to discriminate among native speech sounds improves, whereas the same ability to discriminate among foreign speech sounds decreases. Our study aimed to determine whether this perceptual narrowing is unique to language or might also apply to face processing. We tested discrimination of human and monkey faces by 6-month-olds, 9-month-olds, and adults, using the visual paired-comparison procedure. Only the youngest group showed discrimination between individuals of both species; older infants and adults only showed evidence of discrimination of their own species. These results suggest that the "perceptual narrowing" phenomenon may represent a more general change in neural networks involved in early cognition.     

Benzodiazepine receptor-mediated experimental "anxiety" in primates

The ethyl ester of beta-carboline-3-carboxylic acid has a high affinity for benzodiazepine receptors in the brain. In the rhesus monkey this substance produces an acute behavioral syndrome characterized by dramatic elevations in heart rate, blood pressure, plasma cortisol, and catecholamines. The effects are blocked by benzodiazepines and the specific benzodiazepine receptor antagonist Ro 15-1788. The benzodiazepine receptor may consist of several subsites or functional domains that independently recognize agonist, antagonists, or "active" antagonists such as beta-carboline-3-carboxylic acid ethyl ester. These results suggest that the benzodiazepine receptor is involved in both the affective and physiological manifestations of anxiety, and that the administration of beta-carboxylic acid ethyl ester to monkeys may provide a reliable and reproducible animal model of human anxiety.     

Subhuman primate diploid cells: possible substrates for production of virus vaccines

Results of a program for development of new cell lines suggest that it it possible to establish cell lines from both rhesus and African green monkeys which are comparable to diploid lines of human origin, and that these monkey lines should be candidates for use in the production of virus vaccines.     

Amino acid content of rabbit acrosomal proteinase and its similarity to human trypsin

Rabbit acrosomal proteinase from epididymal spermatozoa of 44 male rabbits was purified by subcellular fractionation, sucrose density gradient centrifugation, and electrofocusing; the specific activity of the purified product was 20,047 units per milligram, a value similar to that observed for pancreatic trypsins from various sources. The molecular weight determined from the amino acid analyses and ultracentrifugation was about 22,000. This rabbit acrosomal proteinase showed great similarity to pancreatic trypsin, especially to human pancreatic trypsin, both in the number of individual amino acids and in the total number of residues. This similarity was confirmed by an antigenic cross reaction between rabbit antiserum to bovine pancreatic trypsin with human, rabbit, rhesus monkey, and bull acrosotnal proteinase.     

Rhesus monkey vestibular cortex: a bimodal primary projection field

Single units in the rhesus monkey (Macaca mulata) cortex responded to both vestibular and proprioceptive somatosensory stimuli. This bimodal response characteristic is unlike the modality specificity noted for other primary sensory fields. The vestibular field is located, contrary to previous opinion, within a distinct cytoarchitectonic area outside of area 2.     

Simian AIDS: isolation of a type D retrovirus and transmission of the disease

A type D retrovirus related to but distinct from Mason-Pfizer monkey virus was isolated in vitro from the blood of two rhesus monkeys (Macaca mulatta) with simian acquired immunodeficiency syndrome (SAIDS). Three juvenile rhesus monkeys that were injected intravenously with tissue culture fluids containing this virus developed SAIDS after 2 to 4 weeks.     

Cultivation in vitro of the quartan malaria parasite Plasmodium inui

The simian guartan malaria parasite Plasmodium inui (OS strain) was cultured in a continuous flow system with rhesus monkey erythrocytes and RPMI 1640nmedium supplemented with Hepes buffer and rhesus serum. Over a 10-week period, the growth of the parasite permitted a 61,000-fold cumulative dilution of the original inoculum. After 5 weeks in culture, the parasites were still infective to the monkey Saimiri sciureus and to Anopheles freeborni mosquitoes.     

Mental rotation of the neuronal population vector

A rhesus monkey was trained to move its arm in a direction that was perpendicular to and counterclockwise from the direction of a target light that changed in position from trial to trial. Solution of this problem was hypothesized to involve the creation and mental rotation of an imagined movement vector from the direction of the light to the direction of the movement. This hypothesis was tested directly by recording the activity of cells in the motor cortex during performance of the task and computing the neuronal population vector in successive time intervals during the reaction time. The population vector rotated gradually counterclockwise from the direction of the light to the direction of the movement at an average rate of 732 degrees per second. These results provide direct, neural evidence for the mental rotation hypothesis and indicate that the neuronal population vector is a useful tool for "reading out" and identifying cognitive operations of neuronal ensembles.     

A new type D retrovirus isolated from macaques with an immunodeficiency syndrome

Macaque monkeys with the recently described acquired immunodeficiency syndrome show a marked defect in T-lymphocyte function and die with opportunistic infections and lymphoproliferative abnormalities. In the study described here a new type D retrovirus was isolated from two Macaca cyclopis with this syndrome. This virus is related to, but distinct from, Mason-Pfizer monkey virus, a type D retrovirus previously isolated from a mammary tumor of a rhesus monkey (Macaca mulatta).     

Autoimmune encephalomyelitis and ocular lesions in monkeys sensitized during the neonatal period

The neonatal rhesus monkey is susceptible to the induction of autoimmune encephalomyelitis. The disease has been produced regularly by injection of neonatal animals with guinea pig spinal cord antigen in complete Freund's adjuvant. The onset of the disease, as compared with onset in adults, is delayed and is most often heralded by intrinsic eye lesions, notably widespread retinal hemorrhages.     

Anopheles hackeri,a vector of Plasmodium knowlesi in Malaya

Anopheles hackeri, a mosquito commonly found breeding in nipa palm leaf bases along the Malayan coast, was demonstrated to be infected with Plasmodium knowlesi by the inoculation of sporozoites into an uninfected rhesus monkey. This was the first demonstration of a natural vector of any monkey malaria.     

Anti-inflammatory activity of human IgG4 antibodies by dynamic Fab arm exchange

Antibodies play a central role in immunity by forming an interface with the innate immune system and, typically, mediate proinflammatory activity. We describe a novel posttranslational modification that leads to anti-inflammatory activity of antibodies of immunoglobulin G, isotype 4 (IgG4). IgG4 antibodies are dynamic molecules that exchange Fab arms by swapping a heavy chain and attached light chain (half-molecule) with a heavy-light chain pair from another molecule, which results in bispecific antibodies. Mutagenesis studies revealed that the third constant domain is critical for this activity. The impact of IgG4 Fab arm exchange was confirmed in vivo in a rhesus monkey model with experimental autoimmune myasthenia gravis. IgG4 Fab arm exchange is suggested to be an important biological mechanism that provides the basis for the anti-inflammatory activity attributed to IgG4 antibodies.     

Neural basis of orientation perception in primate vision

Orientational differences in human visual acuity can be related parametrically to the distribution of optimal orientations for the receptive fields of neurons in the striate cortex of the rhesus monkey. Both behavioral measures of acuity and the distribution of receptive fields exhibit maximums for stimuli horizontal or vertical relative to the retina; the effect diminishes with distance from the fovea. The anisotropy in the neuronal population and in visual acuity appear to be determined by postnatal visual experience.     

Electrocortical correlates of stimulus response and reinforcement

Three patterns of electrical response were identified in the occipital cortex of rhesus monkeys making a differential discrimination: an input pattern that identifies which stimulus has been displayed; a reinforcement pattern that indicates whether the outcome of the differential response was rewarded or in error; and an intention pattern that occurs prior to the response and predicts which response the monkey is about to make. Neither the reinforcement nor the intention pattern is present while the monkeys perform at chance; at this time, only the differences due to input can be distinguished. These results suggest that more than simple input transmission is occurring in the primary visual mechanism. The influence of the experience of the organism is apparently encoded in the averaged electrical potentials recorded from the striate cortex.     

Application and Assessment of Ketamine-Xylidinothiazoline Combinations for Anaesthesia in Rhesus Monkey

The quantitative anaesthesia assessment technique was used to evaluate the effectiveness of ketamine, ketamine-xylidinothiazoline in rhesus monkey. Total 20 healthy adult rhesus monkeys were divided into two groups and anaesthetized using either intramuscular （IM） ketamine （20 mg·kg^-1） or ketamine （5 mg·kg^-1 IM） and xylidinothiazoline （1 mg·kg^-1 IM）. During anaesthesia rectal temperature, respiratory rate, heart rate, saturation of blood oxygen and blood pressure were recorded. The degree of sedation, analgesia, muscle relaxation were monitored either. The results showed that ketamine alone did not produce adequate anaesthesia, and the combination of xylidinothiazoline and ketamine provided adequate anesthesia for rhesus monkeys with no significant side effects and little effects on respiration and circulation.     

Brain lesions in an infant rhesus monkey treated with monsodium glutamate

In an infant rhesus monkey brain damage resulted from subcutaneously administered monosodium glutamate. Although a relatively high dose of monosodium glutamate was used, the infant was asymptomatic for a 3-hour observation period during which time hypothalamic neurons were undergoing a process of acute cell death. With the electron microscope it was observed that dendrites and cell bodies of neurons are the tissue components primarily affected in brain damage induced by monosodium glutamate.     

Scotopic spectral sensitivity in the monkey

Three rhesus monkeys learned to adjust a small illuminated spot to threshold intensity. Then, while dark adapted, they "tracked" their thresholds to stimuli spaced across the visible wavelength spectrum. Spectral sensitivity functions were determined for each animal from these threshold records. The functions agreed well with results obtained from a human subject in the same apparatus, and with the standard human scotopic function defined by the International Commission on Illumination. However, the monkeys' relative sensitivity was slightly higher in the long-wavelength portion of the spectrum.     

Ontogeny of soluble and mitochondrial tyrosine aminotransferases

The development of the soluble and mitochondrial forms of tyrosine aminotransferase was observed in fetal and neonatal rhesus monkey tissues. The mitochondrial activity is detectable in early fetal life; the soluble form reaches significant activity just before the birth of the animal.