Search

This article presents several abstracts of research papers to be presented at the eleventh annual meeting of the American Society of Primatologists New Orleans, Louisiana June 2-5, 1988. The first paper deals with the implications of "psychological well-being" on primate medicine and colony management, the second one focuses on the influence of gender on paternal kin recognition in captive rhesus monkeys. A yet another paper deals with Methylenedioxymethamphetamine's reducing brain serotonin.

Discusses abstracts of research papers to be presented at the fifteenth annual meeting of the American Society of Primatologists at Glendon College of York University in Toronto, Ontario on June 19-21, 1992. Ultrasonic imaging of ovarian dynamics during the menstrual cycle in rhesus monkeys; Endocrine and behavioral constraints on reproduction in subordinate male common marmosets; Successful implementation of the video-task paradigm with a squirrel monkey.

Hepatitis E virus (HEV) infection is normally transmitted via the faeco–oral route. The possibility that the infection might be transmissible by blood has been suggested. Direct evidence of blood-borne transmission of hepatitis E infection is, however, absent. In this report, 10 ml of plasma obtained from a healthy, but hepatitis E viraemic, blood donor was transfused to a Rhesus monkey. Acute hepatitis E developed following transfusion of blood from the hepatitis E viraemic donor. This was confirmed by virological, immunological, biochemical and histopathological data. These results, combined with other epidemiological findings previously reported, indicate that transfusion-associated hepatitis E can occur. The risk of transfusion-associated HEV infection in endemic areas should be assessed and strategies developed to reduce it. [ABSTRACT FROM AUTHOR]

Simple Summary: At the California National Primate Research Center (CNPRC), rhesus macaques are kept in large, complex social groups outdoors because this environment helps them behave naturally and cope well. However, living in groups can lead to problems, such as fights that sometimes result in injuries. To handle these situations, a team of experts from different fields regularly meets to discuss and decide if any macaques need to be moved to protect them from repeated attacks. The team uses a careful process to identify which animals might be at risk and decide whether the individual should stay in the social group or be relocated, keeping in mind both the animal's well-being and the stability of the whole group. This paper includes real-life examples to show how they make these tough decisions, aiming to keep all the animals physically and mentally healthy while maintaining harmony in the group. At the California National Primate Research Center (CNPRC), the preferred housing for rhesus macaques involves maintaining them in complex social groups outdoors, primarily for breeding purposes. This functionally appropriate environment promotes effective coping through the expression of species-typical behaviors and important aspects of species-typical social structure, thus enabling normal animal development, higher reproductive success, and the production of high-quality biological models. Despite the benefits, social housing introduces challenges like trauma from aggressive interactions. These challenges necessitate a delicate balance between tolerating some aggression and preventing repeated targeting of individuals. Therefore, the CNPRC has established a multidisciplinary working group of behavioral management experts, veterinarians, animal care, and researchers that meets regularly to review cases of animals that may need to be removed from their social group. We discuss the criteria and decision-making processes employed to manage and mitigate aggression. We describe the systematic approach to identifying at-risk individuals and the comprehensive evaluation process that guides whether to relocate an animal from their groups or not. Considerations include the welfare of the individual and the group's social stability. This paper provides case studies demonstrating how the working group applies these criteria and processes in practical scenarios, highlighting the complexities and challenges of such decisions. [ABSTRACT FROM AUTHOR]

This article is an obituary and tribute to William Alvin Mason, a prominent figure in the field of primatology. The article highlights Mason's significant contributions to primatology, psychology, and animal behavior, as well as his mentorship of many scientists. Mason's research focused on surrogate mother research, developmental psychobiology, and the study of titi monkeys. He authored or coauthored over 200 papers and held leadership positions in scientific societies. The text is a collection of personal reflections and tributes from individuals who had a close relationship with Mason, expressing gratitude for his guidance, support, and intellectual contributions. They remember him as a kind and humble individual who made a significant impact on their lives and careers. [Extracted from the article]

The traditional level set algorithm selects the position of the initial contour randomly and lacks the processing of edge information. Therefore, it cannot accurately extract the edge of the brain tissue. In order to solve this problem, this paper proposes a level set algorithm that fuses partition and Canny function. Firstly, the idea of partition is fused, and the initial contour position is selected by combining the morphological information of each region, so that the initial contour contains more brain tissue regions, and the efficiency of brain tissue extraction is improved. Secondly, the canny operator is fused in the energy functional, which improves the accuracy of edge detection of rhesus monkey brain tissue while retaining the advantage of the traditional level set algorithm in processing an uneven gray image. Experimental results show that the algorithm can accurately extract the brain tissue of rhesus monkeys with an accuracy of up to 86%. [ABSTRACT FROM AUTHOR]

The phonetic potential of nonhuman primate vocal tracts has been the subject of considerable contention in recent literature. Here, the work of Philip Lieberman (1934−2022) is considered at length, and two research papers—both purported challenges to Lieberman's theoretical work—and a review of Lieberman's scientific legacy are critically examined. I argue that various aspects of Lieberman's research have been consistently misinterpreted in the literature. A paper by Fitch et al. overestimates the would‐be "speech‐ready" capacities of a rhesus macaque, and the data presented nonetheless supports Lieberman's principal position—that nonhuman primates cannot articulate the full extent of human speech sounds. The suggestion that no vocal anatomical evolution was necessary for the evolution of human speech (as spoken by all normally developing humans) is not supported by phonetic or anatomical data. The second challenge, by Boë et al., attributes vowel‐like qualities of baboon calls to articulatory capacities based on audio data; I argue that such "protovocalic" properties likely result from disparate articulatory maneuvers compared to human speakers. A review of Lieberman's scientific legacy by Boë et al. ascribes a view of speech evolution (which the authors term "laryngeal descent theory") to Lieberman, which contradicts his writings. The present article documents a pattern of incorrect interpretations of Lieberman's theoretical work in recent literature. Finally, the apparent trend of vowel‐like formant dispersions in great ape vocalization literature is discussed with regard to Lieberman's theoretical work. The review concludes that the "Lieberman account" of primate vocal tract phonetic capacities remains supported by research: the ready articulation of fully human speech reflects species‐unique anatomy. Highlights: The work by phonetician and cognitive scientist Philip Lieberman on the phonetic capacities of nonhuman primates has been challenged in recent years.None of these challenges seriously dispute the core tenet of Lieberman's claims that nonhuman primates cannot articulate the full extent of human speech sounds, resulting from species' limitations on articulatory anatomy.Misunderstandings of Lieberman's work are seemingly widespread in the literature and point to a critical dearth of knowledge of human speech production and articulation in the fields of primatology and bioacoustics. [ABSTRACT FROM AUTHOR]

In this paper I recall some of the significant moments of my career as a primatologist, including some of the intellectual conflicts I encountered between anthropology, sociology and zoology. From an initial interest in ethics and evolution, I undertook research on rhesus monkeys in captivity and then on chimpanzees in the wild. Influenced by Japanese primatology as well as Western approaches, this led to my work on the problems of describing primate behaviour, but this more theoretical approach was superseded by empirical work embodied in the founding of the Budongo Conservation Field Station. I describe the initial creation of the field station in 1990 and some of the research directions we have followed since that time. The paper ends with a focus on conservation, this being of increasing importance as the Budongo Forest faces ever increasing threats from industry. [ABSTRACT FROM AUTHOR]

This paper attempts to theorize from two peripheries within the Indian 'knowledge production nexus': one which is spatial vis-à-vis a 'peripheral' city; and the other which is relational vis-à-vis more-than-human relations in the city. Drawing from Southern and postcolonial urban theory and more-than-human geographies, we postulate that first, the city of Guwahati in North-East India remains a 'South within the South' as a site to theorize from, and second, the everyday enmeshed lives and relations of animals within this landscape remain negligible within the above-mentioned discursive nexus. In a parallel enquiry over 'other Souths' and 'other lifeforms', we explore animals' geographies in Guwahati, finding potential in the framing of 'entanglements' to encapsulate varied relations with pigs, rhesus macaques, bovines, and dogs – both historically and in the contemporary. More-than-human entanglements, we contend, unveil more-than-human material, spatial, and liminal relations in the city, striated along economic, gender, caste, and class lines. Such a framing is both located and dislocated, suggestive of a comparative analytic and a plural ethic. [ABSTRACT FROM AUTHOR]

Studying dynamic spatiotemporal patterns of early brain development in macaque monkeys is critical for understanding the cortical organization and evolution in humans, given the phylogenetic closeness between humans and macaques. However, due to huge challenges in the analysis of early brain Magnetic Resonance Imaging (MRI) data typically with extremely low contrast and dynamic imaging appearances, our knowledge of the early macaque cortical development remains scarce. To fill this critical gap, this paper characterizes the early developmental patterns of cortical thickness and surface area in rhesus macaques by leveraging advanced computing tools tailored for early developing brains based on a densely sampled longitudinal dataset with 140 rhesus macaque MRI scans seamlessly covering from birth to 36 mo of age. The average cortical thickness exhibits an inverted U-shaped trajectory with peak thickness at around 4.3 mo of age, which is remarkably in line with the age of peak thickness at 14 mo in humans, considering the around 3:1 age ratio of human to macaque. The total cortical surface area in macaques increases monotonically but with relatively lower expansions than in humans. The spatial distributions of thicker and thinner regions are quite consistent during development, with gyri having a thicker cortex than sulci. By 4 mo of age, over 81% of cortical vertices have reached their peaks in thickness, except for the insula and medial temporal cortices, while most cortical vertices keep expanding in surface area, except for the occipital cortex. These findings provide important insights into early brain development and evolution in primates. [ABSTRACT FROM AUTHOR]

Laboratory animal research with nonhuman primates (NHPs) requires anesthesia for most procedures to ensure safety and consistency in sample collection. However, anesthesia drugs can have adverse effects on the physiological measures of interest. Alfaxalone, most notably used in dogs and cats, offers rapid onset, short duration of action, and has a high safety margin. Here, we compared our current anesthesia protocol using Telazol, to three different doses of alfaxalone during a one-hour intravenous glucose tolerance test, the standard evaluation of glucose metabolism in NHPs. Results indicate there are no differences in the rate of glucose metabolism, anesthesia depth measurements, or total duration of sedation, but induction, number of supplemental doses required, and recovery time to eating were affected by the different doses of alfaxalone. Cardiovascular measures showed variability between the four protocols in respiratory rate and systolic blood pressure rates only. These results indicate that alfaxalone can produce a reliable state of anesthesia, similar to our current protocol, and confers minimal cardiovascular or metabolic disturbance, as well as enhanced recovery characteristics. As such, alfaxalone is a promising anesthetic for use in laboratory animals and further investigation is warranted. [ABSTRACT FROM AUTHOR]

In this study, the higher order interactions, which are complex interactions involving more than two neurons, are studied in two real-world networks. These interactions play a crucial role in the brain's functioning, as they can influence the network's synchronization and dynamics. This paper analyzes the application of directed simplicial complexes, the mathematical realization of the higher order interactions, to study the synchronization of two Macaque rhesus brain networks. Interestingly, the directionally allows for the consideration of different simplicial motifs. The Hindmarsh–Rose chaotic system has been used to model the node dynamics. Also, electrical and chemical couplings are considered to be the interaction mechanism. The findings from this study provide valuable insights into the complex dynamics of brain networks. [ABSTRACT FROM AUTHOR]

Objectives: Estimation of body mass from skeletal metrics can reveal important insights into the paleobiology of archeological or fossil remains. The standard approach constructs predictive equations from postcrania, but studies have questioned the reliability of traditional measures. Here, we examine several skeletal features to assess their accuracy in predicting body mass. Materials and Methods: Antemortem mass measurements were compared with common skeletal dimensions from the same animals postmortem, using 115 rhesus macaques (male: n = 43; female: n = 72). Individuals were divided into training (n = 58) and test samples (n = 57) to build and assess Ordinary Least Squares or multivariate regressions by residual sum of squares (RSS) and AIC weights. A leave‐one‐out approach was implemented to formulate the best fit multivariate models, which were compared against a univariate and a previously published catarrhine body‐mass estimation model. Results: Femur circumference represented the best univariate model. The best model overall was composed of four variables (femur, tibia and fibula circumference and humerus length). By RSS and AICw, models built from rhesus macaque data (RSS = 26.91, AIC = −20.66) better predicted body mass than did the catarrhine model (RSS = 65.47, AIC = 20.24). Conclusion: Body mass in rhesus macaques is best predicted by a 4‐variable equation composed of humerus length and hind limb midshaft circumferences. Comparison of models built from the macaque versus the catarrhine data highlight the importance of taxonomic specificity in predicting body mass. This paper provides a valuable dataset of combined somatic and skeletal data in a primate, which can be used to build body mass equations for fragmentary fossil evidence. [ABSTRACT FROM AUTHOR]

A critical turning point was reached in research with the recent success in cloning rhesus monkeys (Macaca mulatta), a major advancement in primatology. This breakthrough marks the beginning of a new age in biomedical research, ushered by improved somatic cell nuclear transfer techniques and creative trophoblast replacement strategies. The successful cloning of rhesus monkeys presents the possibility of producing genetically homogeneous models that are highly advantageous for studying complex biological processes, testing drugs, and researching diseases. However, this achievement raises important ethical questions, particularly regarding animal welfare and the broader ramifications of primate cloning. Approaching the future of primate research with balance is critical, as the scientific world stands on the brink of these revolutionary breakthroughs. This paper aims to summarise the consequences, ethical challenges and possible paths forward in primatology arising from rhesus monkey cloning. [ABSTRACT FROM AUTHOR]

The pathogenesis of ricin toxicity following inhalation has been investigated in many animal models, including the non-human primate (predominantly the rhesus macaque), pig, rabbit and rodent. The toxicity and associated pathology described in animal models are broadly similar, but variation appears to exist. This paper reviews the published literature and some of our own unpublished data and describes some of the possible reasons for this variation. Methodological variation is evident, including method of exposure, breathing parameters during exposure, aerosol characteristics, sampling protocols, ricin cultivar, purity and challenge dose and study duration. The model species and strain used represent other significant sources of variation, including differences in macro- and microscopic anatomy, cell biology and function, and immunology. Chronic pathology of ricin toxicity by inhalation, associated with sublethal challenge or lethal challenge and treatment with medical countermeasures, has received less attention in the literature. Fibrosis may follow acute lung injury in survivors. There are advantages and disadvantages to the different models of pulmonary fibrosis. To understand their potential clinical significance, these factors need to be considered when choosing a model for chronic ricin toxicity by inhalation, including species and strain susceptibility to fibrosis, time it takes for fibrosis to develop, the nature of the fibrosis (e.g., self-limiting, progressive, persistent or resolving) and ensuring that the analysis truly represents fibrosis. Understanding the variables and comparative aspects of acute and chronic ricin toxicity by inhalation is important to enable meaningful comparison of results from different studies, and for the investigation of medical countermeasures. [ABSTRACT FROM AUTHOR]

REGN‐EB3 (Inmazeb) is a cocktail of three human monoclonal antibodies approved for treatment of Ebola infection. This paper describes development of a mathematical model linking REGN‐EB3's inhibition of Ebola virus to survival in a non‐human primate (NHP) model, and translational scaling to predict survival in humans. Pharmacokinetic/pharmacodynamic data from single‐ and multiple‐dose REGN‐EB3 studies in infected rhesus macaques were incorporated. Using discrete indirect response models, the antiviral mechanism of action was used as a forcing function to drive the reversal of key Ebola disease hallmarks over time, for example, liver and kidney damage (elevated alanine [ALT] and aspartate aminotransferases [AST], blood urea nitrogen [BUN], and creatinine), and hemorrhage (decreased platelet count). A composite disease characteristic function was introduced to describe disease severity and integrated with the ordinary differential equations estimating the time course of clinical biomarkers. Model simulation results appropriately represented the concentration‐dependence of the magnitude and time course of Ebola infection (viral and pathophysiological), including time course of viral load, ALT and AST elevations, platelet count, creatinine, and BUN. The model estimated the observed survival rate in rhesus macaques and the dose of REGN‐EB3 required for saturation of the pharmacodynamic effects of viral inhibition, reversal of Ebola pathophysiology, and survival. The model also predicted survival in clinical trials with appropriate scaling to humans. This mathematical investigation demonstrates that drug‐disease modeling can be an important translational tool to integrate preclinical data from an NHP model recapitulating disease progression to guide future translation of preclinical data to clinical study design. [ABSTRACT FROM AUTHOR]

Public health threat coming from a rapidly developing COVID-19 pandemic calls for developing safe and effective vaccines with innovative designs. This paper presents preclinical trial results of "Betuvax-CoV-2", a vaccine developed as a subunit vaccine containing a recombinant RBD-Fc fusion protein and betulin-based spherical virus-like nanoparticles as an adjuvant ("Betuspheres"). The study aimed to demonstrate vaccine safety in mice, rats, and Chinchilla rabbits through acute, subchronic, and reproductive toxicity studies. Along with safety, the vaccine demonstrated protective efficacy through SARS-CoV-2-neutralizing antibody production in mice, rats, hamsters, rabbits, and primates (rhesus macaque), and lung damage and infection protection in hamsters and rhesus macaque model. Eventually, "Betuvax-CoV-2" was proved to confer superior efficacy and protection against the SARS-CoV-2 in preclinical studies. Based on the above results, the vaccine was enabled to enter clinical trials that are currently underway. [ABSTRACT FROM AUTHOR]

The article presents information about various issues related to immunology that will be published in the forthcoming issue of the journal "Immunology." Some of the topics are Haiyan Li: Detection of thyroglobulin mRNA as truncated isoform(s) in mouse thymus, written by George Carayanniotis; Induction of Human Papillomavirus Type 16-specific immunologic responses in a normal and an HPV infected populations, written by Chi-an Chen, Cheng Wen-Fang, Lee Chien-Nan, Su Yi-Ning, Chang Ming-Cheng, Hsiao Wen-Chun, Hsieh Chang-Yao; Cloning and characterisation of equine CD89 and identification of the CD89 gene in Chimpanzees and Rhesus macaques written by H. Morton, Richard Pleass, Anne Storset, Per Brandtzaeg, Jenny Woof.

During fixation and between saccades, our eyes undergo diffusive random motion called fixational drift. The role of fixational drift in visual coding and inference has been debated in the past few decades, but the mechanisms that underlie this motion remained unknown. In particular, it has been unclear whether fixational drift arises from peripheral sources, or from central sources within the brain. Here we show that fixational drift is correlated with neural activity, and identify its origin in central neural circuitry within the oculomotor system, upstream to the ocular motoneurons (OMNs). We analyzed a large data set of OMN recordings in the rhesus monkey, alongside precise measurements of eye position, and found that most of the variance of fixational eye drifts must arise upstream of the OMNs. The diffusive statistics of the motion points to the oculomotor integrator, a memory circuit responsible for holding the eyes still between saccades, as a likely source of the motion. Theoretical modeling, constrained by the parameters of the primate oculomotor system, supports this hypothesis by accounting for the amplitude as well as the statistics of the motion. Thus, we propose that fixational ocular drift provides a direct observation of diffusive dynamics in a neural circuit responsible for storage of continuous parameter memory in persistent neural activity. The identification of a mechanistic origin for fixational drift is likely to advance the understanding of its role in visual processing and inference. Between saccades, our eyes undergo random movements called fixational drift, but what drives this motion has remained elusive. In this paper, the authors demonstrate that a central neural circuit within the oculomotor system drives fixational drift. [ABSTRACT FROM AUTHOR]

Co-variations in resting state activity are thought to arise from a variety of correlated inputs to neurons, such as bottom-up activity from lower areas, feedback from higher areas, recurrent processing in local circuits, and fluctuations in neuromodulatory systems. Most studies have examined resting state activity throughout the brain using MRI scans, or observed local co-variations in activity by recording from a small number of electrodes. We carried out electrophysiological recordings from over a thousand chronically implanted electrodes in the visual cortex of non-human primates, yielding a resting state dataset with unprecedentedly high channel counts and spatiotemporal resolution. Such signals could be used to observe brain waves across larger regions of cortex, offering a temporally detailed picture of brain activity. In this paper, we provide the dataset, describe the raw and processed data formats and data acquisition methods, and indicate how the data can be used to yield new insights into the 'background' activity that influences the processing of visual information in our brain. Measurement(s) brain activity measurement • eye movement Technology Type(s) extracellular electrophysiology recording • multi-electrode array system • infrared camera Factor Type(s) visual stimulation Sample Characteristic - Organism Macaca mulatta [ABSTRACT FROM AUTHOR]

Rhesus macaques (Macaca mulatta) are among the most extensively studied of nonhuman primates. This species has been the subject of many investigations concerning basic primate biology and behavior, including studies of social organization, developmental psychology, physiology, endocrinology, and neurodevelopment. Rhesus macaques are also critically important as a nonhuman primate model of human health and disease, including use in studies of infectious diseases, metabolic diseases, aging, and drug or alcohol abuse. Current research addressing fundamental biological and/or applied biomedical questions benefits from various genetic and genomic analyses. As a result, the genome of rhesus macaques has been the subject of more study than most nonhuman primates. This paper briefly discusses a number of information resources that can provide interested researchers with access to genetic and genomic data describing the content of the rhesus macaque genome, available information regarding genetic variation within the species, results from studies of gene expression, and other aspects of genomic analysis. Specific online databases are discussed, including the US National Center for Biotechnology Information, the University of California Santa Cruz genome browser, Ensembl genome browser, the Macaque Genotype and Phenotype database (mGAP), Rhesusbase, and others. [ABSTRACT FROM AUTHOR]

Ethnozoological practices to cure various diseases have a long history. Communities that reside near the forest collect wild animals and their derivatives to prepare medicines and get relief from diseases. Northeastern India is home to many tribes with vast traditional ethnobiological knowledge, and there are many reports of zootherapeutic uses in the region. In an attempt to understand primate-based ethnozoologic use in the area a literature survey was carried out using different sources. The findings revealed that Hoolock hoolock was the most used species among the primates (48 %), followed by Macaca assamensis (20 %) and Macaca mulatta (10 %). Among the materials used, the flesh of primates was the most dominant (43 %), followed by the blood (20 %) and brain (14 %). This paper highlights the negative effects of ethno-medicinal uses of primates to draw the attention of conservationists and encourage conservation education to address the damage to primates in the name of health care. Government agencies are also requested to strengthen health care systems to discourage the killing of valuable primate species. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate the ability of a glass-ionomer cement-base material to prevent bacterial penetration along the dentin interface and to compare it with two conventional cement-base materials. A total of 107 Class 5 restorations was placed in Rhesus monkey teeth by means of three test materials [zinc oxide-eugenol (ZOE), copalite varnish + zinc phosphate cement base (V + ZP), and a glass-ionomer lining cement (GI)], with unetched and unbonded resin composite used alone as a control material and as a final restoration over the test base materials. Following disinfection, Class 5 cavities were prepared on the buccal surfaces of the teeth to the inner one-half of dentin. A sterile filter-paper disk was then placed on the axial wall and covered with a Teflon disk. Next, the cavities were based to the dento-enamel junction with one of the test base materials and finally restored with unetched and unbonded resin composite. After five and 16 weeks, the filter-paper disks were retrieved and cultivated for the presence and type of bacteria. The five-week results showed positive growth in two groups: the composite-only controls and the V + ZP group. The 16-week results showed growth in all of the test groups, but only one of nine teeth showed growth in the zinc oxide-eugenol group and one of 16 teeth in the glass-ionomer group. The results of this study indicate that under the conditions tested, a glass-ionomer base was capable of minimizing bacterial penetration along the material-tooth interface. [ABSTRACT FROM AUTHOR]

Presents an abstract of the study `Bone Mineral Density and Osteoporosis in the Rhesus Monkeys of Cayo Santiago' by A.M. Cerroni, M.D. Grynpas, et al.

Nonhuman primates have a highly diverse locomotor repertoire defined by an equally diverse hand use. Based on how primates use their hands during locomotion, we can distinguish between terrestrial and arboreal taxa. The 'arboreal' hand is likely adapted towards high wrist mobility and grasping, whereas the 'terrestrial' hand will show adaptations to loading. While the morphology of the forearm and hand bones have been studied extensively, functional adaptations in the forearm and hand musculature to locomotor behaviour have been documented only scarcely. In this paper, we investigate the forelimb musculature of the highly arboreal gibbons (including Hylobates lar,Hylobates pileatus,Nomascus leucogenys,Nomascus concolor and Symphalangus syndactylus) and compare this with the musculature of the semi‐terrestrial rhesus macaques (Macaca mulatta). Anatomical data from previous dissections on knuckle‐walking bonobos (Pan paniscus) and bipedal humans (Homo sapiens) are also included to further integrate the analyses in the scope of catarrhine hand adaptation. This study indicates that the overall configuration of the arm and hand musculature of these primates is very similar but there are some apparent differences in relative size which can be linked to differences in forelimb function and which might be related to their specific locomotor behaviour. In macaques, there is a large development of wrist deviators, wrist and digital flexors, and m. triceps brachii, as these muscles are important during the different phases of palmi‐ and digitigrade quadrupedal walking to stabilize the wrist and elbow. In addition, their m. flexor carpi ulnaris is the most important contributor to the total force‐generating capacity of the wrist flexors and deviators, and is needed to counteract the adducting torque at the elbow joint during quadrupedal walking. Gibbons show a relatively high force‐generating capacity in their forearm rotators, wrist and digital flexors, which are important muscles in brachiation to actively regulate forward movement of the body. The results also stress the importance of the digital flexors in bonobos, during climbing and clambering, and in humans, which is likely linked to our advanced manipulation skills. [ABSTRACT FROM AUTHOR]

Orientation selectivity, as an emergent property of neurons in the visual cortex, is of critical importance in the processing of visual information. Characterizing the orientation selectivity based on neuronal firing activities or local field potentials (LFPs) is a hot topic of current research. In this paper, we used cross-frequency coupling and least absolute shrinkage and selection operator (LASSO) to predict the grating orientations in V1 and V4 of two rhesus monkeys. The experimental data were recorded by utilizing two chronically implanted multi-electrode arrays, which were placed, respectively, in V1 and V4 of two rhesus monkeys performing a selective visual attention task. The phase–amplitude coupling (PAC) and amplitude–amplitude coupling (AAC) were employed to characterize the cross-frequency coupling of LFPs under sinusoidal grating stimuli with different orientations. Then, a LASSO logistic regression model was constructed to predict the grating orientation based on the strength of PAC and AAC. Moreover, the cross-validation method was used to evaluate the performance of the model. It was found that the average accuracy of the prediction based on the combination of PAC and AAC was 73.9%, which was higher than the predicting accuracy with PAC or AAC separately. In conclusion, a LASSO logistic regression model was introduced in this study, which can predict the grating orientations with relatively high accuracy by using PAC and AAC together. Our results suggest that the principle behind the LASSO model is probably an alternative direction to explore the mechanism for generating orientation selectivity. [ABSTRACT FROM AUTHOR]

Non-human primate models are widely used in studying the brain mechanism underlying brain development, cognitive functions, and psychiatric disorders. Neuroimaging techniques, such as magnetic resonance imaging, play an important role in the examinations of brain structure and functions. As an indispensable tool for brain imaging data analysis, brain atlases have been extensively investigated, and a variety of versions constructed. These atlases diverge in the criteria based on which they are plotted. The criteria range from cytoarchitectonic features, neurotransmitter receptor distributions, myelination fingerprints, and transcriptomic patterns to structural and functional connectomic profiles. Among them, brainnetome atlas is tightly related to brain connectome information and built by parcellating the brain on the basis of the anatomical connectivity profiles derived from structural neuroimaging data. The pipeline for building the brainnetome atlas has been published as a toolbox named ATPP (A Pipeline for Automatic Tractography-Based Brain Parcellation). In this paper, we present a variation of ATPP, which is dedicated to monkey brain parcellation, to address the significant differences in the process between the two species. The new toolbox, MonkeyCBP, has major alterations in three aspects: brain extraction, image registration, and validity indices. By parcellating two different brain regions (posterior cingulate cortex) and (frontal pole) of the rhesus monkey, we demonstrate the efficacy of these alterations. The toolbox has been made public (https://github.com/bheAI/MonkeyCBP%5fCLI, https://github.com/bheAI/MonkeyCBP%5fGUI). It is expected that the toolbox can benefit the non-human primate neuroimaging community with high-throughput computation and low labor involvement. [ABSTRACT FROM AUTHOR]

Eye movements in daily life occur in rapid succession and often without a predefined goal. Using a free viewing task, we examined how fixation duration prior to a saccade correlates to visual saliency and neuronal activity in the superior colliculus (SC) at the saccade goal. Rhesus monkeys (three male) watched videos of natural, dynamic, scenes while eye movements were tracked and, simultaneously, neurons were recorded in the superficial and intermediate layers of the superior colliculus (SCs and SCi, respectively), a midbrain structure closely associated with gaze, attention, and saliency coding. Saccades that were directed into the neuron's receptive field (RF) were extrapolated from the data. To interpret the complex visual input, saliency at the RF location was computed during the pre-saccadic fixation period using a computational saliency model. We analyzed if visual saliency and neural activity at the saccade goal predicted pre-saccadic fixation duration. We report three major findings: (1) Saliency at the saccade goal inversely correlated with fixation duration, with motion and edge information being the strongest predictors. (2) SC visual saliency responses in both SCs and SCi were inversely related to fixation duration. (3) SCs neurons, and not SCi neurons, showed higher activation for two consecutive short fixations, suggestive of concurrent saccade processing during free viewing. These results reveal a close correspondence between visual saliency, SC processing, and the timing of saccade initiation during free viewing and are discussed in relation to their implication for understanding saccade initiation during real-world gaze behavior. [ABSTRACT FROM AUTHOR]

Interaction with host cell receptors initiates internalization of Kaposi's sarcoma-associated herpesvirus (KSHV) particles. Fusion of viral and host cell membranes, which is followed by release of the viral capsid into the cytoplasm, is executed by the core fusion machinery composed of glycoproteins H (gH), L (gL), and B (gB), that is common to all herpesviruses. KSHV infection has been shown to be sensitive to inhibitors of vacuolar acidification, suggestive of low pH as a fusion trigger. To analyze KSHV entry at the single particle level we developed dual-fluorescent recombinant KSHV strains that incorporate fluorescent protein-tagged glycoproteins and capsid proteins. In addition, we generated a hybrid rhesus monkey rhadinovirus (RRV) that expresses KSHV gB in place of RRV gB to analyze gB-dependent differences in infection pathways. We demonstrated lytic reactivation and infectivity of dual-fluorescent KSHV. Confocal microscopy was used to quantify co-localization of fluorescently-tagged glycoproteins and capsid proteins. Using the ratio of dual-positive KSHV particles to single-positive capsids as an indicator of fusion events we established KSHV fusion kinetics upon infection of different target cells with marked differences in the "time-to-fusion" between cell types. Inhibition of vesicle acidification prevented KSHV particle-cell fusion, implicating low vesicle pH as a requirement. These findings were corroborated by comparison of RRV-YFP wildtype reporter virus and RRV-YFP encoding KSHV gB in place of RRV gB. While RRV wt infection of receptor-overexpressing cells was unaffected by inhibition of vesicle acidification, RRV-YFP expressing KSHV gB was sensitive to Bafilomycin A1, an inhibitor of vacuolar acidification. Single- and dual-fluorescent KSHV strains eliminate the need for virus-specific antibodies and enable the tracking of single viral particles during entry and fusion. Together with a hybrid RRV expressing KSHV gB and classical fusion assays, these novel tools identify low vesicle pH as an endocytotic trigger for KSHV membrane fusion. Author summary: All herpesviruses encode a fusion protein, gB, which fuses the virus membrane with host membranes. Membrane fusion is essential for infection by enveloped viruses. Under conditions where gB proteins from other herpesviruses fuse cells into syncytia, KSHV gB does not readily fuse cells, and KSHV infection was previously shown to be inhibited by substances that raise the pH of endocytotic vesicles. We therefore sought to test whether fusion of KSHV viral particles with cellular membranes is a pH-dependent step. We developed two tools to test this hypothesis. The first tool is a dual-fluorescent KSHV with differently colored protein tags at the viral envelope and the capsid, which lose colocalization upon fusion and release of the capsid from the membrane, but not in the presence of an inhibitor of vesicle acidification. The second tool is a hybrid RRV strain that expresses KSHV gB instead of RRV gB. RRV infected receptor-overexpressing cells in a manner that was not inhibited by an inhibitor of vesicle acidification. The hybrid RRV expressing KSHV gB on the other hand was sensitive to inhibition of vesicle acidification. Together, these findings show that KSHV gB dictates a low-pH, endocytotic route of infection. [ABSTRACT FROM AUTHOR]

Various mature tissue-resident cells exhibit progenitor characteristics following injury. However, the existence of endogenous stem cells with multiple lineage potentials in the adult spinal cord remains a compelling area of research. In this study, we present a cross-species investigation that extends from development to injury. We used single-nucleus transcriptomic sequencing and genetic lineage tracing to characterize neural cells in the spinal cord. Our findings show that ciliated ependymal cells lose neural progenitor gene signatures and proliferation ability following the differentiation of NPCs within the ventricular zone. By combining single-nucleus transcriptome datasets from the rhesus macaque spinal cord injury (SCI) model with developmental human spinal cord datasets, we revealed that ciliated ependymal cells respond minimally to injury and cannot revert to a developmental progenitor state. Intriguingly, we observed astrocytes transdifferentiating into mature oligodendrocytes postinjury through lineage tracing experiments. Further analysis identifies an intermediate-state glial cell population expressing both astrocyte and oligodendrocyte feature genes in adult spinal cords. The transition ratio from astrocytes into oligodendrocytes increased after remodeling injury microenvironment by functional scaffolds. Overall, our results highlight the remarkable multilineage potential of astrocytes in the adult spinal cord. [ABSTRACT FROM AUTHOR]

Broadly neutralizing antibodies (bnAbs) against HIV-1 have been shown to protect from systemic infection. When employing a novel challenge virus that uses HIV-1 Env for entry into target cells during the first replication cycle, but then switches to SIV Env usage, we demonstrated that bnAbs also prevented mucosal infection of the first cells. However, it remained unclear whether antibody Fc-effector functions contribute to this sterilizing immunity. Therefore, additional challenge viruses were produced that contain SIV Env and graded doses of a fusion-defective trimer of HIV-1 Env, to which the bnAb, PGT121 can bind without interfering with the SIV Env-based cell entry. After administration of either PGT121 or its mutant deficient in Fc-effector functions, rhesus macaques were intrarectally exposed to these challenge viruses and to those using either HIV-1 Env or SIV Env for entry into the first cells. Both antibodies similarly reduced infection events with the challenge virus using HIV-1 Env by a factor close to 200. Incorporating fusion-defective HIV-1 Env trimers into the particles of the challenge viruses at densities observed in primary virus isolates did not reduce SIV Env-mediated infection events. The results indicate that the sparsity of bnAb binding-sites on HIV-1 virions limits the contribution of Fc-effector functions to provide sterilizing immunity against mucosal viral infection. Hence, harnessing Fc-effector functions for sterilizing immunity against mucosal HIV-1 infection may require strategies to increase the degree of antibody opsonization. Author summary: Control of the HIV pandemic remains a world-wide health challenge. Although antibodies against HIV have been shown to protect from HIV infection, the precise step during mucosal acquisition of HIV infection and the mechanisms involved are not fully understood. Using a unique infection model in non-human primates that assesses the efficacy of antibodies in preventing infection of the first cells we demonstrate that a non-neutralizing antibody that binds to the challenge virus without blocking viral entry into the cell does not protect. Under neutralizing conditions, the same antibody prevented infection of the first cells independent of its interaction with Fc-receptors required for non-neutralizing mechanisms of protection. Therefore, we conclude that harnessing non-neutralizing mechanisms of anti-HIV antibodies to provide sterilizing immunity may require strategies to improve the density of antibodies binding to the surface of HIV particles. [ABSTRACT FROM AUTHOR]

Exposure to early life adversity is linked to detrimental fitness outcomes across taxa. Owing to the challenges of collecting longitudinal data, direct evidence for long-term fitness effects of early life adversity from long-lived species remains relatively scarce. Here, we test the effects of early life adversity on male and female longevity in a free-ranging population of rhesus macaques (Macaca mulatta) on Cayo Santiago, Puerto Rico. We leveraged six decades of data to quantify the relative importance of 10 forms of early life adversity for 6599 macaques. Individuals that experienced more early life adversity died earlier than those that experienced less adversity. Mortality risk was highest during early life, defined as birth to 4 years old, but heightened mortality risk was also present in macaques that survived to adulthood. Females and males were affected differently by some forms of adversity, and these differences might be driven by varying energetic demands and dispersal patterns. Our results show that the fitness consequences of early life adversity are not uniform across individuals but vary as a function of the type of adversity, timing and social context, and thus contribute to our limited but growing understanding of the evolution of early life sensitivities. This article is part of the discussion meeting issue 'Understanding age and society using natural populations' [ABSTRACT FROM AUTHOR]

The recent worldwide outbreaks of mpox prioritize the development of a safe and effective mRNA vaccine. The contemporary mpox virus (MPXV) exhibits changing virological and epidemiological features, notably affecting populations already vulnerable to human immunodeficiency virus (HIV). Herein, we profile the immunogenicity of AR-MPXV5, a penta-component mRNA vaccine targeting five specific proteins (M1R, E8L, A29L, A35R, and B6R) from the representative contemporary MPXV clade II strain, in both naive and simian immunodeficiency virus (SIV)-infected nonhuman primates. Immunization with two doses of AR-MPXV5 to cynomolgus macaques effectively elicits antibody responses and cellular responses. Importantly, based on the challenge model with a contemporary MPXV clade II strain, AR-MPXV5 demonstrates effective efficacy in preventing skin lesions, eliminating viremia and reducing viral loads in multiple tissues after challenge in naive male animals. More importantly, AR-MPXV5 is well-tolerated in stable chronic SIV-infected rhesus monkeys, while eliciting comparable MPXV-specific humoral and cellular responses in both naive and SIV-infected monkeys. Together, these results support further clinical development of the AR-MPXV5 vaccine. Here, the authors report immunogenicity and safety of AR-MPXV5, a penta-component mRNA vaccine, in naive and simian immunodeficiency virus infected nonhuman primates (NHPs), and demonstrate protection in naïve male NHPs after immunization with two doses of AR-MPXV5. [ABSTRACT FROM AUTHOR]

Low cerebrospinal (CSF) arginine vasopressin (AVP) concentration is a biomarker of social impairment in low-social monkeys and children with autism, suggesting that AVP administration may improve primate social functioning. However, AVP administration also increases aggression, at least in "neurotypical" animals with intact AVP signaling. Here, we tested the effects of a voluntary drug administration method in low-social male rhesus monkeys with high autistic-like trait burden. Monkeys received nebulized AVP or placebo, using a within-subjects design. Study 1 (N = 8) investigated the effects of AVP administration on social cognition in two tests comparing responses to social versus nonsocial stimuli. Test 1: Placebo-administered monkeys lacked face recognition memory, whereas face recognition memory was "rescued" following AVP administration. In contrast, object recognition memory was intact and did not differ between administration conditions. Test 2: Placebo-administered monkeys did not respond to conspecific social communication cues, whereas following AVP administration, they reciprocated affiliative communication cues with species-typical affiliative responses. Importantly, AVP administration did not increase aggressive responses to conspecific aggressive or affiliative overtures. Study 2 (N = 4) evaluated the pharmacokinetics of this administration method. Following AVP nebulization, we observed a linear increase in cisternal CSF AVP levels, and a quadratic rise and fall in blood AVP levels. These findings indicate that nebulized AVP likely penetrates the central nervous system, selectively promotes species-typical responses to social information, and does not induce aggression in low-social individuals. Nebulized AVP therefore may hold promise for managing similar social symptoms in people with autism, particularly in very young or lower functioning individuals. [ABSTRACT FROM AUTHOR]

Background: Benzodiazepines bind to γ-aminobutyric acid type A (GABAA) receptor subtypes identified by different α subunits (i.e., α1GABAA, α2GABAA, α3GABAA, and α5GABAA). Sedative-motor effects of benzodiazepines are thought to involve α1GABAA and α3GABAA subtypes. Aims: We evaluated observable measures of sedative-motor effects and species-typical behaviors in monkeys following acute administration of novel GABAkines (positive allosteric modulators of GABAA receptors), with varying degrees of selective efficacy at different GABAA receptor subtypes. We predicted that the induction of sedative-motor effects would depend on the degree of α1GABAA and α3GABAA efficacy. Methods: Adult female rhesus monkeys (N = 4) were implanted with chronic indwelling i.v. catheters. Quantitative behavioral observation was conducted by trained observers following administration of multiple doses of the conventional benzodiazepine alprazolam and the GABAkines MP-III-80 (preferential efficacy at α2/α3/α5GABAA subtypes), KRM-II-81, MP-III-24 (both with preferential efficacy for α2/α3GABAA subtypes), and MP-III-22 (preferential potency and efficacy for α5GABAA subtypes). Results: As with alprazolam, all GABAkines induced significant levels of mild sedation ("rest/sleep posture"). Deep sedation was observed with alprazolam, MP-III-80, and MP-III-22; motoric effects (observable ataxia) were obtained with alprazolam, KRM-II-81, and MP-III-22 only. Surprisingly, the order of potency for rest/sleep posture was significantly associated only with potency at α5GABAA subtypes. Conclusions: GABAkines with preferential efficacy at α2/α3GABAA and/or α5GABAA subtypes engendered sedative-motor effects in monkeys, although only compounds with α5GABAA activity engendered deep sedation. Moreover, the significant relationship between potency obtained with in vitro electrophysiology data and the rest/sleep posture measure suggests a role for the α5GABAA subtype in this milder form of sedation. [ABSTRACT FROM AUTHOR]

Presents an abstract of the study `Ontogeny of positional behavior in (Macaca Mulatta): Substrate associations,' by J.P. Wells and J.E. Turnquist. Changes in locomotor and postural behavior among primates; Ontogenetic changes in morphology that limit positional behavior.

Presents an abstract of the study `Validation of the Fecal Extraction Method: Correlation of Serum and Fecal Endocrine Profiles in Rhesus macaques, Macaca mulatta,' by R.C. Stavisky, M. Wilson, E. Russell and P.L. Whitten. Use of fecal steroid extraction methods to monitor reproductive function in free-ranging primates; Data on captive rhesus macaque females.

Presents an abstract of the study `Heritability of gross hemispheric asymmetry in rhesus macaques (Macaca mulatta),' by A.V. Masters. Study of endocasts from rhesus macaque skulls from the Cayo Santiago skeletal collection; Effects of heritability on the lateralization of several cranial features.

Presents an abstract of the study `Influences on mount series duration in free-ranging rhesus macaques (Macaca mulatta),' by J.H. Manson. Function of series mounting among male rhesus macaques; Frequency of copulation and ejaculation.

Presents an abstract of the study `Individual differences in growth and dental development of Rhesus monkeys and their implications for fossil primates,' by J.E. Bowman. Reconstruction of life history parameters in fossil hominids; Inter-specific correlations between life history variables, growth and dental development in modern primates.

A Rhesus monkey, serologically grouped as B, has been shown to excrete low-molecular-weight carbohydrate material in urine closely related to that found in human urine. Galactose feeding resulted in the excretion of a trisaccharide which was shown to be identical to the trisaccharide isolated from the urine of group B humans under the same conditions. Experiments in which [14C]galactose was administered both orally and via an intestinal vein demonstrated that the intestine is the site of biosynthesis. [ABSTRACT FROM AUTHOR]

Estabishing the features of lethal aggression and patterns of aggressive behavior in monkeys, as well as assessing the age and sex structure of aggressors and victims, are important for tracing the evolutionary roots of lethal aggression in humans and developing the measures to prevent its manifestations in monkeys held in captivity. The aim of the study was to characterize species-specific features of conspecific lethal aggression in captive macaques, baboons and guenons. The intra-group lethal aggression events were analyzed over a 10-year period in rhesus macaques (Macaca mulatta), crab-eating macaques (Macaca fascicularis), pig-tail macaques (Macaca nemestrina), green monkeys (Chlorocebus aethiops), hamadryas baboons (Papio hamadryas), and anubis baboons (Papio anubis), kept in social groups. Such events were found to occur in all the six monkey species studied. In groups consisting of adult males, the maximum frequency of occurrence of lethal aggression events was observed in the rhesus macaques, while the minimum in hamadryas baboons. Species-specific differences were found in the patterns of lethal aggression in conspecific family groups consisting of males, females, babies and juveniles. In hamadryas baboons, anubis baboons and pig-tail macaques, i.e., in species with a pronounced sexual dimorphism in body size and social status, the main form of lethal aggression in family groups was infanticide committed by a single sexually mature male. In rhesus monkeys, crab-eating macaques and green monkeys, i.e., the species characterized by a relatively mild sexual dimorphism in body size and social status, the prevailing form of lethal aggression in family groups was a coalitionary violence of females toward young and adult members of the same group. [ABSTRACT FROM AUTHOR]

Motor intention decoding is one of the most challenging issues in brain machine interface (BMI). Despite several important studies on accurate algorithms, the decoding stage is still processed on a computer, which makes the solution impractical for implantable applications due to its size and power consumption. This study aimed to provide an appropriate real-time decoding approach for implantable BMIs by proposing an agile decoding algorithm with a new input model and implementing efficient hardware. This method, unlike common ones employed firing rate as input, used a new input space based on spike train temporal information. The proposed approach was evaluated based on a real dataset recorded from frontal eye field (FEF) of two male rhesus monkeys with eight possible angles as the output space and presented a decoding accuracy of 62%. Furthermore, a hardware architecture was designed as an application-specific integrated circuit (ASIC) chip for real-time neural decoding based on the proposed algorithm. The designed chip was implemented in the standard complementary metal-oxide-semiconductor (CMOS) 180 nm technology, occupied an area of 4.15 mm 2 , and consumed 28.58 μ W @1.8 V power supply. [ABSTRACT FROM AUTHOR]