Tissue Cell
December 2024
SARS-Cov-2 is a corona virus that causes COVID-19 disease, a viral infection responsible for the pandemic decreed by the World Health Organization in March 2020. Angiotensin-converting enzyme 2 (ACE-2) functions as the main receptor for SARS-Cov-2. The study aimed to detect the expression of ACE-2 in the gastrointestinal tract, kidney, and lung in the rhesus monkeys and squirrel monkeys.
View Article and Find Full Text PDFThe study of nonhuman primates (NHP) can provide significant insights into our understanding numerous infectious agents. The etiological agent of COVID-19, SARS-CoV-2 virus, first emerged in 2019 and has so far been responsible for the deaths of over 4 million people globally. In the frenzied search to understand its pathogenesis and immunology and to find measures for prevention and control of this pandemic disease, NHP, particularly macaques, are the preferred model because they manifest similar clinical signs and immunologic features as humans.
View Article and Find Full Text PDFJ Med Primatol
February 2023
Background: Nonhuman primates (NHPs) are fundamental for countless types of research and their phylogenetic similarities with humans make them valuable biomodels. Saimiri (squirrel monkeys) is the New World simian genus that is most widely used in research; however, little is known about the morphology of the gastrointestinal tract (GIT) of these animals.
Methods: The morphological and topographical aspects of GIT organs from 14 previously frozen carcasses of captive squirrel monkeys (Saimiri sciureus) were described as a means for refining clinical and laboratory diagnoses, with the aim of providing a basis for clinical assessments and animal management.
Despite worldwide efforts to understand the transmission dynamics of Zika virus (ZIKV), scanty evaluation has been made on the vector competence of fed directly on viremic human and non-human primates (NHPs). We blood-fed from two districts in Rio de Janeiro on six ZIKV infected pregnant rhesus macaques at several time points, half of which were treated with Sofosbuvir (SOF). Mosquitoes were analyzed for vector competence after 3, 7 and 14 days of incubation.
View Article and Find Full Text PDFThe outbreaks of Zika virus (ZIKV) infection in Brazil, 2015-2016, were associated with severe congenital malformations. Our translational study aimed to test the efficacy of the antiviral agent sofosbuvir (SOF) against vertical transmission of ZIKV and the associated congenital syndrome (CZS), using a rhesus monkey model. Eight pregnant macaques were successfully infected during the organogenesis phase with a Brazilian ZIKV strain; five of them received SOF from two to fifteen days post-infection.
View Article and Find Full Text PDFAims: Ectopic fat is a recognized contributor to insulin resistance and metabolic dysfunction, while the role of fat deposition inside intestinal wall tissue remains understudied. We undertook this study to directly quantify and localize intramural fat deposition in duodenal tissue and determine its association with adiposity.
Methods: Duodenal tissues were collected from aged (21.
Non-human primates (NHP) are suitable models for studying different aspects of the human system, including pathogenesis and protective immunity to many diseases. However, the lack of specific immunological reagents for neo-tropical monkeys, such as , is still a major factor limiting studies in these models. An alternative strategy to circumvent this obstacle has been the selection of immunological reagents directed to humans, which present cross-reactivity with NHP molecules.
View Article and Find Full Text PDFA major constraint in the study of malaria, including vaccine development, lies on the parasite's strict human host specificity and therefore the shortage of animal experimental models able to harbor human plasmodia. The best experimental models are neo-tropical primates of the genus Saimiri and Aotus, but they require splenectomy to reduce innate defenses for achieving high and consistent parasitemias, an important limitation. Clodronate-liposomes (CL) have been successfully used to deplete monocytes/macrophages in several experimental models.
View Article and Find Full Text PDFChanges in cerebral blood flow (CBF) during a hyperglycemic challenge were mapped, using perfusion-weighted MRI, in a group of non-human primates. Seven female baboons were fasted for 16 h prior to 1-h imaging experiment, performed under general anesthesia, that consisted of a 20-min baseline, followed by a bolus infusion of glucose (500 mg/kg). CBF maps were collected every 7 s and blood glucose and insulin levels were sampled at regular intervals.
View Article and Find Full Text PDFBackground: The understanding of the mechanisms of immunity in malaria is crucial for the rational development of interventions such as vaccines. During blood stage infection, the spleen is considered to play critical roles in both immunity and immunopathology of Plasmodium falciparum infections.
Methods: Saimiri sciureus monkeys were inoculated with blood stages of P.
Obesity is a risk factor for several diseases including type 2 diabetes and cardiovascular disease. The aim of this study was to compare the relationships of waist circumference and body weight with circulating markers of metabolic, cardiovascular, and hepatic function in chimpanzees (Pan troglodytes). After a 12-h fast, blood was collected from 39 adult captive chimpanzees for measurement of serum glucose, BUN, creatinine, albumin, cholesterol, ALT, AST, ALP, total and direct bilirubin, triglyceride, and insulin, and waist circumference and body weight were measured.
View Article and Find Full Text PDFNon-specific lymphocytic myocarditis (NLM) is frequently observed in baboons within the endemic range of Trypanosoma cruzi. We sought to determine whether T. cruzi infection is a cause of baboon NLM.
View Article and Find Full Text PDFBackground: There is little information available concerning trichobezoars in the non-human primate literature.
Methods: We evaluated 118 cases of trichobezoar in baboons over a 29-year period at the Southwest National Primate Research Center.
Results: The anatomic locations affected in decreasing order were the stomach, small intestine, cecum, esophagus and colon.
Background: Rhesus monkeys are relevant models for human diseases. The simian immunodeficiency virus (SIV) infection is an useful macaque model for assessing human immunodeficiency virus (HIV) vaccine strategies. Susceptibility and resistance to viruses have been associated with particular major histocompatibility complex (MHC) molecules.
View Article and Find Full Text PDFRev Bras Parasitol Vet
August 2008
Histological lesions in the lungs of rhesus monkeys (Macaca mulatta) related with Pneumonyssus simicola were evidenced. The most prominent pathologic alterations included numerous thin-walled cysts 1-5mm diameter scattered throughout the lungs, bronchiolitis, peribronchiolitis where the mites were found associated with pigmented and non-pigmented materials. Our study included data from 347 rhesus monkeys submitted to necropsies during 20 years.
View Article and Find Full Text PDFCampylobacteriosis is an extremely important zoonosis, circulating freely in the environment. In nonhuman primates kept in open facilities and bred for experimental purposes, the presence of Campylobacter spp. could cause severe damage to the production and interfere with the results of scientific research.
View Article and Find Full Text PDFExp Toxicol Pathol
April 2007
A spontaneous mammary gland ductal carcinoma was diagnosed in a 13-year-old female captive rhesus monkey (Macaca mulatta). The expression of argyrophilic nucleolar organizer regions (AgNORs) was studied to investigate the correlation between the histologic invasiveness and cell proliferation activity assay for predicting the biologic behavior of this tumor type. The results of this study show that the AgNOR size in tumor cells reflect the degree of malignancy when compared with the pattern of peripheral blood lymphocytes of the same individual.
View Article and Find Full Text PDFPhysiological parameters of laboratory animals used for biomedical research is crucial for following several experimental procedures. With the intent to establish baseline biologic parameters for non-human primates held in closed colonies, hematological and morphometric data of captive monkeys were determined. Data of clinically healthy rhesus macaques (Macaca mulatta), cynomolgus monkeys (Macaca fascicularis), and squirrel monkeys (Saimiri sciureus) were collected over a period of five years.
View Article and Find Full Text PDFThe long-term management of breeding colonies requires some measure of genetic diversity in the animal population. For the maintenance of breeding colonies of monkeys used for biomedical research, known pedigrees supply precise data to determine the genetic status of colonies. We present data of genetic analyses in an old closed colony of rhesus macaques (Macaca mulatta) that was established in 1932 with 100 animals.
View Article and Find Full Text PDFAm J Trop Med Hyg
June 2003
Severe chronic damage to the heart and gastrointestinal tract in patients with Chagas' disease are often observed 10-20 years after the acute phase. The course of long-lasting infection with the Colombian strain of Trypanosoma cruzi was studied in seven rhesus monkeys infected for 15-19 years. Subpatent parasitemia was detected in all studied animals, using hemoculture (two of seven), artificial xenodiagnosis (three of seven), and a polymerase chain reaction PCR (six of six).
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