Morphological and molecular characterization of parabasilids isolated from ex situ nonhuman primates and their keepers at different institutions in Brazil.

Intestinal protozoa, which can be asymptomatic or cause diarrhea, dysentery and even death, are among the main agents that affect nonhuman primates (NHPs) kept under human care. Nevertheless, information on the molecular and morphometric profiles of parabasilids in the Neotropics is still scarce. In this context, the objective of this study was to isolate the Parabasalia protozoa detected in the feces of NHPs and their keepers in Pavlova and TYSGM9 media and to characterize the isolates by molecular biology and morphometry. Fecal samples from NHPs from five Brazilian institutions were analyzed. Direct examination was performed immediately after obtaining the samples. A total of 511 fecal samples from NHPs were collected, and 10.6% contained parabasilids. Regarding the handlers, of the 74 samples analyzed, three were positive. In vitro-generated parabasilid isolates were successfully obtained from all positive samples, as identified via microscopy. Isolates of the parasite were obtained both from New World NHPs, including the genera Leontopithecus, Saguinus, Leontocebus, Aotus, Saimiri, Sapajus, and Alouatta, and from the Old World primate Pan troglodytes. Forty-nine NHP isolates were molecularly identified: Pentatrichomonas hominis (16), Trichomitus batrachorum (14), Tetratrichomonas brumpti (13) and Hypotrichomonas hampli (6). The human isolates were identified as Tetratrichomonas sp. (2) and T. batrachorum (1). Visualization and morphometric analysis revealed trophozoites with piriform or rounded shapes that presented variable measurements. The isolates previously characterized as P. hominis had up to five free flagella, while T. batrachorum and Tetratrichomonas sp. had up to four free flagella, and H. hampli had a maximum of three free flagella. These morphometric characteristics corroborated the molecular identification. In general, a variety of parabasilids were observed to infect NHPs, and T. batrachorum was isolated from biological samples from both NHPs and their keepers, a finding that reinforces the susceptibility of these hosts to infections by parabasilids in Brazil.

From imaging to precision: low cost and accurate determination of stereotactic coordinates for brain surgery Sapajus apella using MRI.

The capuchin monkey (Sapajus apella), a New World monkey species, exhibits prominent characteristics that make it an ideal model for neuroscience research. These characteristics include its phylogenetic traits, telencephalization coefficient, anatomical structures and pathways, genetic profile, immune responses, cognitive abilities, and complex behavioral repertoires. Traditionally, methodologies for stereotactic neurosurgery in research models have relied on the use of brain atlases. However, this approach can lead to errors due to the considerable variation in brain size and shape among individual monkeys. To address this issue, we developed a protocol for deriving individual coordinates for each monkey using a straightforward and relatively inexpensive method involving MRI imaging. Our protocol utilizes a specially designed, 3D-printed stereotactic head-holder that is safe to use with an MR magnet, non-invasive placement of fiducial markers, and post-processing with open-source software. This approach enhances MRI data visualization, improves anatomical targeting, and refines the design of neurosurgical experiments. Our technique could also prove beneficial in other areas of neuroscience research that require accurate calculation of stereotaxic coordinates. Furthermore, it could be useful for other nonhuman primate species for which brain atlases are typically unavailable.

Gastrointestinal Parasites Affecting Non-Human Primates That Are Kept Ex Situ and Their Handlers in Different Brazilian Institutions: Diagnosis and Analysis of Risk Factors.

AIM: Determining gastrointestinal parasites' frequency in non-human primates (NHPs) and handlers in different Brazilian institutions, and associate it with management information. METHODS: Different institutions in São Paulo (A), Brasília (B), Rio de Janeiro (C), Pará (D) and Santa Catarina (E) were included in the study. Fecal samples were processed by using coproparasitological techniques; information about NHP handling and professionals' routine were collected through the use of questionnaires. RESULTS: In total, 33.1% of 511 NHP samples were positive for parasites; the Entamoebidae Group and Strongyloides sp.-compatible eggs were the most detected protozoa and helminths, respectively. The Entamoebidae Group was mainly diagnosed in Alouatta from Institutions E and D, and was also the only parasite detected in handlers. Strongyloides-compatible eggs were mostly evident in fecal samples collected from Cebidae from Institutions B and D. Some risk factors associated with parasite infection were a high number of animals in the same enclosure and their use for research protocol purposes, whereas quarantine, a post-infection vacant period in enclosures and antiparasitic supply were categorized as protective factors against these agents' infection. CONCLUSIONS: Parasites showing different transmission routes but concomitantly circulating in NHP institutions located in different Brazilian regions were identified in the current study, with an emphasis on those presenting zoonotic potential.

Experimental Yellow Fever in the Squirrel Monkey (Saimiri spp.): Hematological, Biochemical, and Immunological Findings.

Between 2016 and 2018, Brazil experienced the largest sylvatic epidemic of yellow fever virus (YFV). Despite to the magnitude and rapid spread of the epidemic, little is known about YFV dispersion. The study evaluated whether the squirrel monkey is a good model for yellow fever (YF) studies. Methods: Ten animals were infected with 1 × 106 PFU/mL of YFV, with one negative control. Blood samples were collected daily during the first 7 days and at 10, 20 and 30 days post infection (dpi) for detection of viral load and cytokines by RT-qPCR; measurements of AST, ALT, urea and creatinine were taken; IgM/IgG antibodies were detected by ELISA, and hemagglutination inhibition and neutralization tests were performed. The animals exhibited fever, flushed appearance, vomiting and petechiae, and one animal died. Viremia was detected between 1 and 10 dpi, and IgM/IgG antibodies appeared between 4 and 30 dpi. The levels of AST, ALT and urea increased. The immune responses were characterized by expression of S100 and CD11b cells; endothelial markers (VCAM-1, ICAM-1 and VLA-4), cell death and stress (Lysozyme and iNOS); and pro-inflammatory cytokines (IL-8, TNF-α, and IFN-γ) and anti-inflammatory cytokines (IL-10 and TGF-ß). The squirrel monkeys showed changes similar to those described in humans with YF, and are a good experimental model for the study of YF.

Experimental Yellow Fever in Squirrel Monkey: Characterization of Liver In Situ Immune Response.

Non-human primates contribute to the spread of yellow fever virus (YFV) and the establishment of transmission cycles in endemic areas, such as Brazil. This study aims to investigate virological, histopathological and immunohistochemical findings in livers of squirrel monkeys (Saimiri spp.) infected with the YFV. Viremia occurred 1-30 days post infection (dpi) and the virus showed a predilection for the middle zone (Z2). The livers were jaundiced with subcapsular and hemorrhagic multifocal petechiae. Apoptosis, lytic and coagulative necrosis, steatosis and cellular edema were also observed. The immune response was characterized by the expression of S100, CD11b, CD57, CD4 and CD20; endothelial markers; stress and cell death; pro and anti-inflammatory cytokines, as well as Treg (IL-35) and IL-17 throughout the experimental period. Lesions during the severe phase of the disease were associated with excessive production of apoptotic pro-inflammatory cytokines, such as IFN-γ and TNF-α, released by inflammatory response cells (CD4+ and CD8+ T lymphocytes) and associated with high expression of molecules of adhesion in the inflammatory foci observed in Z2. Immunostaining of the local endothelium in vascular cells and the bile duct was intense, suggesting a fundamental role in liver damage and in the pathogenesis of the disease.

Uniform trichromacy in Alouatta caraya and Alouatta seniculus: behavioural and genetic colour vision evaluation.

Primate colour vision depends on a matrix of photoreceptors, a neuronal post receptoral structure and a combination of genes that culminate in different sensitivity through the visual spectrum. Along with a common cone opsin gene for short wavelengths (sws1), Neotropical primates (Platyrrhini) have only one cone opsin gene for medium-long wavelengths (mws/lws) per X chromosome while Paleotropical primates (Catarrhini), including humans, have two active genes. Therefore, while female platyrrhines may be trichromats, males are always dichromats. The genus Alouatta is inferred to be an exception to this rule, as electrophysiological, behavioural and molecular analyses indicated a potential for male trichromacy in this genus. However, it is very important to ascertain by a combination of genetic and behavioural analyses whether this potential translates in terms of colour discrimination capability. We evaluated two howler monkeys (Alouatta spp.), one male A. caraya and one female A. seniculus, using a combination of genetic analysis of the opsin gene sequences and a behavioral colour discrimination test not previously used in this genus. Both individuals completed the behavioural test with performances typical of trichromatic colour vision and the genetic analysis of the sws1, mws, and lws opsin genes revealed three different opsin sequences in both subjects. These results are consistent with uniform trichromacy in both male and female, with presumed spectral sensitivity peaks similar to Catarrhini, at ~ 430 nm, 532 nm, and 563 nm for S-, M- and L-cones, respectively.

Menadione reduces CDC25B expression and promotes tumor shrinkage in gastric cancer.

Background: Gastric cancer is one of the most incident types of cancer worldwide and presents high mortality rates and poor prognosis. MYC oncogene overexpression is a key event in gastric carcinogenesis and it is known that its protein positively regulates CDC25B expression which, in turn, plays an essential role in the cell division cycle progression. Menadione is a synthetic form of vitamin K that acts as a specific inhibitor of the CDC25 family of phosphatases. Methods: To better understand the menadione mechanism of action in gastric cancer, we evaluated its molecular and cellular effects in cell lines and in Sapajus apella, nonhuman primates from the new world which had gastric carcinogenesis induced by N-Methyl-N-nitrosourea. We tested CDC25B expression by western blot and RT-qPCR. In-vitro assays include proliferation, migration, invasion and flow cytometry to analyze cell cycle arrest. In in-vivo experiments, in addition to the expression analyses, we followed the preneoplastic lesions and the tumor progression by ultrasonography, endoscopy, biopsies, histopathology and immunohistochemistry. Results: Our tests demonstrated menadione reducing CDC25B expression in vivo and in vitro. It was able to reduce migration, invasion and proliferation rates, and induce cell cycle arrest in gastric cancer cell lines. Moreover, our in-vivo experiments demonstrated menadione inhibiting tumor development and progression. Conclusions: We suggest this compound may be an important ally of chemotherapeutics in the treatment of gastric cancer. In addition, CDC25B has proven to be an effective target for investigation and development of new therapeutic strategies for this malignancy.

Comparison of semen characteristics and sperm cryopreservation in common marmoset (Callithrix jacchus) and black-tufted-ear marmoset (Callithrix penicillata).

BACKGROUND: The common marmoset (Callithrix jacchus) is one of the most studied Neotropical primates regarding reproduction. However, little has been reported on the black-tufted-ear marmoset (Callithrix penicillata), which may produce fertile hybrids with other Callithrix. This is the first study to evaluate sperm freezing from black-tufted-ear marmoset. METHODS: Testicles from all animals were measured, and semen was collected by penile vibrostimulation. Samples were analyzed after collection, after chilling and addition of glycerol, and after thawing. RESULTS AND CONCLUSIONS: Fresh semen from both species was similar in many aspects. Additionally, there is a relationship between total motility, plasma membrane integrity, and acrosome integrity observed in sperm samples from both species. We managed to evaluate fresh and thawed sperm with suitable methods for use under zoo or field conditions. However, TEST egg yolk with glycerol at 4% and 6% concentration was not effective for sperm protection in both species during cryopreservation.

Deregulation of the SRC Family Tyrosine Kinases in Gastric Carcinogenesis in Non-human Primates.

BACKGROUND/AIM: The evolution of gastric carcinogenesis remains largely unknown, as the regulatory mechanisms involved in the aggressiveness of gastric cancer are still poorly understood. Kinases are downstream modulators and effectors of various cell signaling cascades and play key roles in the development of neoplastic diseases. The objective of this study was to evaluate the expression of genes and proteins of the SRC family, including FYN, YES, BLK, FGR, LYN and SRC, in a model of intestinal gastric carcinogenesis generated by treating Cebus apella, a New World non-human primate, with N-methyl nitrosourea (MNU). MATERIALS AND METHODS: mRNA expression of genes was measured by real-time reverse transcription quantitative PCR (RT-qPCR) and protein expression was measured by western blotting in six Cebus apella treated with N-methyl-nitrosourea (MNU) for about 2.5 years. RESULTS: Elevated mRNA and protein expression mainly of the SRC and LYN kinases was observed. Their expression was gradually increasing as non-atrophic gastritis was evolving to gastric cancer. CONCLUSION: SRC family kinases play a key role in tumor progression and metastasis and may be a promising target for the treatment of gastric cancer.

Pelvimetry in Squirrel Monkeys (Saimiri scireus Linnaeus, 1758) / Pelvimetria em macacos-de-cheiro (Saimiri scireus Linnaeus, 1758)

Saimiri sciureus is a neotropical primate widely used in research. However, there are still difficulties regarding their reproduction in vivaria due to the high incidence of dystocia. Dystocia in primates can be caused by cephalopelvic disproportion and in Squirrel Monkeys, pregnancy of large fetuses were reported. This paper describes pelvimetry data of adult females and subadults in specimens of Squirrel Monkeys, from a research colony of Para, Brazil. Pelvic radiographs were obtained in ventrodorsal projections and the following measurements were taken: superior bi-iliac diameter (SBID); inferior bi-iliac diameter (IBID); bi-iliac average diameter (BIAD); right diagonal diameter (RDD); left diagonal diameter (LDD); sacro-pubic diameter (SPD); Based on the obtained diameters, the entrance area of the pelvis (EAP) was also calculated. The average values of the pelvic diameters and EAP in adult females were SBID 1.714cm, BIAD 1.957cm, IBID 1.686cm, RDD 2.771cm, LDD 2.764cm, SPD 2.543cm and EAP 3.9056cm2; and subadult females: 1.588cm SBID, 1.850cm BIAD, 1.625cm IBID, 2.50cm RDD, LDD 2.474cm, 1.95cm SPD and 2.8293 cm2 EAP. Saimiri sciureus pelvis is characterized as dolichopelvic. There was statistical significance between the values for adult females and subadults to SBID, BIAD, RDD, LDD, SPD and EAP. The values of SBID and IBID were lower when compared to the published data for the same species. The result found on this paper will serve as a basis for future studies using pelvic measurements and dystocia prediction of neotropical primates and comparison between different vivaria.(AU)

Saimiri sciureus é uma espécie de primata neotropical muito utilizada como animal de pesquisa. No entanto ainda há dificuldades em biotérios quanto a sua reprodução devido à alta ocorrência de distocia. A distocia em primatas pode ter origem devido à desproporção cefalopélvica, sendo que em macacos-de-cheiro é relatada a gestação de fetos grandes. O presente trabalho descreve dados de pelvimetria em espécimes de macaco-de-cheiro, fêmeas adultas e subadultas provenientes de uma colônia de pesquisa do Pará, Brasil. Foram realizadas radiografias da pelve em projeção ventrodorsal e por meio destas mensurados os diâmetros biilíaco superior (DBIS); diâmetro biíliaco inferior (DBII); diâmetro biilíaco médio (DBIM); diâmetro diagonal direito (DDD); diâmetro diagonal esquerdo (DDE); diâmetro sacro-púbico (DSP); com base nos diâmetros obtidos também foi calculada a área de entrada da pelve (AEP). Os valores médios dos diâmetros pélvicos e da AEP em fêmeas adultas foram: DBIS 1,714cm, DBIM 1,957cm, DBII 1,686cm, DDD 2,771cm, DDE 2,764cm, DSP 2,543cm e AEP 3,9056cm2; e para fêmeas subadultas: 1,588cm DBIS, 1,850cm DBIM, 1,625cm DBII, 2,50cm DDD, 2,474cm DDE, 1,95cm DSP e 2,8293 cm2 AEP. Observou-se que a pelve de Saimiri sciureus é dolicopélvica. Houve diferença estatística significativa entre os valores para fêmeas adultas e subadultas para DBIS, DBIM, DDD, DDE, DSP e AEP. Em comparação com dados da literatura de pelvimetria para S. sciureus observaram-se menores valores de DBIS e DBII. O resultado deste trabalho servirá como base para futuros estudos utilizando-se mensurações pélvicas e predição de distocia em primatas neotropicais e referência para comparação entre S. sciureus de diferentes biotérios.(AU)

Collection, Evaluation, and Coagulum Dissolution of Semen from Goeldi's Monkey, Callimico goeldii.

Research on Neotropical primates' reproduction is necessary due to the lack of available information and the increasing threat to these species. Callimico goeldii is listed as Vulnerable on the IUCN Red List of Threatened Species. This study aimed to test rectal electrostimulation for semen collection and evaluate seminal characteristics. Therefore, semen from 6 captive Goeldi's monkeys was collected and, for the first time, seminal characteristics are described. Coagulum formation was noted in all ejaculates, and we obtained partial or complete liquefaction of the samples. Results were (means ± SD): volume = 26.9 ± 11.87 µL; pH = 7.61 ± 0.28; concentration = 143.18 ± 174.96 × 106 spermatozoa/mL; total sperm motility = 83.33 ± 5.16%; linear progressive motility = 46 ± 24.08%; plasma membrane integrity = 36.38 ± 16.11%; acrosome integrity using fast-green/bengal-rose staining = 63.41 ± 11.72%, and kit Spermac® = 69.36 ± 11.81%; abnormal sperm = 72.5 ± 17.7%, with 16.2 ± 7.7% major defects and 56.3 ± 10% minor defects; sperm with high mitochondrial activity class I = 16.45 ± 22.25%. Rectal electrostimulation was an efficient method for semen collection in this species. Investigations are required to improve semen collection and handling, including cryopreservation methods.

Organic effects of associating paclitaxel with a lipid-based nanoparticle system on a nonhuman primate, Cebus apella.

Lipid-based nanoparticle systems have been used as vehicles for chemotherapeutic agents in experimental cancer treatments. Those systems have generally been credited with attenuating the severe toxicity of chemotherapeutic agents. This study aimed to investigate the effects of associating paclitaxel (PTX) with a lipid-based nanoparticle system on a nonhuman primate, Cebus apella, documenting the toxicity as measured by serum biochemistry, which is a detailed analysis of blood and tissue. Eighteen C. apella were studied: three animals were treated with cholesterol-rich nanoemulsion (LDE) only, without PTX, administered intravenously every 3 weeks, during six treatment cycles; six animals were treated with PTX associated with LDE at the same administration scheme, three with lower (175 mg/m2) and three with higher (250 mg/m2) PTX doses; and six animals were treated with commercial PTX, three with the lower and three with the higher doses. In the LDE-PTX group, no clinical toxicity appeared, and the weight-food consumption curve was similar to that of the controls. Two animals treated with commercial PTX presented weight loss, nausea and vomiting, diarrhea, skin flaking, 70% loss of body hair, and decreased physical activity. The use of LDE as a carrier at both lower and higher doses reduced the toxicity of the drug in this species, which is closely related to human subjects. This was observed not only by clinical, biochemical, and hematological profiles but also by the histopathological analysis. The results of this study support the assumption that lipid-based nanoparticle systems used as drug carriers can serve as valuable tools to decrease the toxicity and increase the safety of chemotherapeutic agents.

Antiviral activity of chloroquine against dengue virus type 2 replication in Aotus monkeys.

Dengue virus (DENV) of the Flaviviridae family is a single positive-stranded RNA virus that is transmitted by Aedes aegypti and Aedes albopictus mosquitoes. The objective of this study was to investigate the use of chloroquine (CLQ) as an antiviral drug against dengue virus in monkeys. To analyze the action of the drug in vivo, nonhuman primates groups (Aotus azarai infulatus) were inoculated with a subcutaneous injection of a virulent strain of DENV-2, treated and untreated CLQ. Blood hematological, viremia, and serum biochemical values were obtained from 16 DENV-2-inoculated, treated and untreated; four received only CLQ and one mock-infected Aotus monkeys. Monkey serum samples (day 0-10 post-inoculation) were assayed by reverse transcription polymerase chain reaction and Cytometric Bead Array for determination of viremia and inflammatory cytokines, respectively. Additionally, body temperature and activity levels were determined. In the present work, CLQ was effective on replication of DENV-2 in Aotus monkeys; a time viremia reduction was observed compared with the controls. The concentration of tumor necrosis factor alpha and interferon gamma in the serum of the animals had a statistically significant reduction in the groups treated with CLQ after infection compared with the controls. A significant decrease in systemic levels of the liver enzyme aspartate aminotransferase (AST) was also observed in the animals treated with CLQ after infection compared with the controls. These results suggest that CLQ interferes in DENV-2 replication in Aotus monkeys.

Ganglion cell and displaced amacrine cell density distribution in the retina of the howler monkey (Alouatta caraya).

Unlike all other New World (platyrrine) monkeys, both male and female howler monkeys (Alouatta sp.) are obligatory trichromats. In all other platyrrines, only females can be trichromats, while males are always dichromats, as determined by multiple behavioral, electrophysiological, and genetic studies. In addition to obligatory trichromacy, Alouatta has an unusual fovea, with substantially higher peak cone density in the foveal pit than every other diurnal anthropoid monkey (both platyrrhines and catarrhines) and great ape yet examined, including humans. In addition to documenting the general organization of the retinal ganglion cell layer in Alouatta, the distribution of cones is compared to retinal ganglion cells, to explore possible relationships between their atypical trichromacy and foveal specialization. The number and distribution of retinal ganglion cells and displaced amacrine cells were determined in six flat-mounted retinas from five Alouatta caraya. Ganglion cell density peaked at 0.5 mm between the fovea and optic nerve head, reaching 40,700-45,200 cells/mm2. Displaced amacrine cell density distribution peaked between 0.5-1.75 mm from the fovea, reaching mean values between 2,050-3,100 cells/mm2. The mean number of ganglion cells was 1,133,000±79,000 cells and the mean number of displaced amacrine cells was 537,000±61,800 cells, in retinas of mean area 641±62 mm2. Ganglion cell and displaced amacrine cell density distribution in the Alouatta retina was consistent with that observed among several species of diurnal Anthropoidea, both platyrrhines and catarrhines. The principal alteration in the Alouatta retina appears not to be in the number of any retinal cell class, but rather a marked gradient in cone density within the fovea, which could potentially support high chromatic acuity in a restricted central region.

Evaluation of the immunological cellular response of Cebus apella exposed to the carcinogen N-methyl-N-nitrosourea and treated with CANOVA®.

The immune response modifier Canova® is a homeopathic remedy indicated for patients with depressed immune system, since this drug appears to increase adaptive immunity and induce an immune response against multiple and severe pathological conditions, including cancer. We evaluated the pattern of immune cellular response in non-human primates of the species Cebus apella exposed to N-methyl-N-nitrosourea (MNU) with and without Canova®. Twelve animals were divided into four groups, with three animals each: negative control and three experimental groups, MNU-alone (35 days); MNU (35 days)-plus-Canova® (3 days) and Canova®-alone (3 days). The animals received MNU orally and Canova® by three intravenous injections. Evaluation of the cellular immune response was performed by immunophenotyping of T-lymphocytes (CD4(+), CD8(+)), B-lymphocytes and natural killer cells. Analysis was also performed of the cell cycle. Our results suggest an increase of T-lymphocytes (CD4(+)CD3(+)) only in the Canova® group, while in the MNU-plus-Canova® group only B-lymphocytes increased.

Semen characteristics of captive common marmoset (Callithrix jacchus): a comparison of a German with a Brazilian colony.

BACKGROUND: The common marmoset (Callithrix jacchus) is of interest for reproductive studies because of their high and variable fertility in captivity. However, to understand this variability, much basic information still needs to be gathered. This study is the first to characterize marmoset semen comparing a German and a Brazilian colony. METHODS: All animals were weighted, and semen samples were collected by penile vibratory stimulation and analyzed according to standard criteria. RESULTS AND CONCLUSIONS: The German animals had a higher mean and maximum weight than the Brazilian. Further, sperm concentration tended to be higher with heavier animals in the German population, but not in the Brazilian. Additionally, major defects tended to be more frequent with higher weight but also only in German sample. In spite of these differences, the total range and variability in sperm concentration were similar in both populations, suggesting that this is characteristic for the species.

Scaling the primate lateral geniculate nucleus: niche and neurodevelopment in the regulation of magnocellular and parvocellular cell number and nucleus volume.

New stereological assessments of lateral geniculate nucleus (LGN) neuron numbers and volumes in five New World primates (Cebus apella, Saguinus midas niger, Alouatta caraya, Aotus azarae, and Callicebus moloch) and compiled LGN volumes for an additional 26 mammals were analyzed for a better understanding of visual system evolution. Both the magnocellular (M)- and the parvocellular (P)-cell populations scale allometrically with brain volume in primates, P cells with a significantly higher slope such that, for every increase in M neuron number, P neuron numbers more than double (ln scale; y = 0.89x + 2.42R(2) = 0.664). In diurnal primates, the ratio of P to M cells was slightly but significantly higher than in nocturnal primates. For all mammals, including primates, LGN volume was unrelated to nocturnal or diurnal niche but showed marked differences in slope and intercept depending on taxonomic group. The allometric scaling of M and P cells can be related to the order of neurogenesis, with late-generated P cells increasing with positive allometry compared with the earlier-generated M cells. This developmental regularity links relative foveal representation to relative isocortex enlargement, which is also generated late. The small increase in the P/M cell ratio in diurnal primates may result from increased developmental neuron loss in the M-cell population as it competes for limited termination zones in primary visual cortex.

hTERT and TP53 deregulation in intestinal-type gastric carcinogenesis in non-human primates.

Despite the high incidence, the molecular events involved in intestinal-type gastric carcinogenesis remains unclear. We previously established an intestinal-type gastric carcinogenesis model in Cebus apella, a New World monkey. In the present study, we evaluated hTERT and TP53 mRNA expression, as well as their protein immunoreactivity, in normal mucosa, non-atrophic gastritis, atrophic gastritis, intestinal metaplasia, and intestinal-type gastric cancer samples of non-human primates treated with N-methyl-nitrosourea. In addition, we evaluated the number of TP53 copies in these samples. Although hTERT immunoreactivity was only detected in gastric cancer, a continuous increase of hTERT mRNA expression was observed from non-atrophic gastritis to gastric tumors. No sample presented p53 immunoreactivity. However, we also observed a continuous decrease of TP53 mRNA expression during the sequential steps of gastric carcinogenesis. Moreover, loss of TP53 copies was observed in intestinal metaplasia and gastric cancer samples. Our study highlights that hTERT and TP53 have a key role in intestinal-type gastric cancer initiation.

The protective effect of Canova homeopathic medicine in cyclophosphamide-treated non-human primates.

BACKGROUND: Canova activates macrophages and indirectly induces lymphocyte proliferation. Here we evaluated the effects of Canova in cyclophosphamide-treated non-human primates. METHODS: Twelve Cebus apella were evaluated. Four animals were treated with Canova only. Eight animals were treated with two doses of cyclophosphamide (50 mg/kg) and four of these animals received Canova. Body weight, biochemistry and hematologic analyses were performed for 40 days. Micronucleus and comet assays were performed for the evaluation of DNA damage. RESULTS: We observed that cyclophosphamide induced abnormal WBC count in all animals. However, the group treated with cyclophosphamide plus Canova presented a higher leukocyte count than that which received only cyclophosphamide. Cyclophosphamide induced micronucleus and DNA damage in all animals. The frequency of these alterations was significantly lower in the Canova group than in the group without this medicine. CONCLUSIONS: Our results demonstrated that Canova treatment minimizes cyclophosphamide myelotoxicity in C. apella.

Lymphocyte proliferation stimulated by activated Cebus apella macrophages treated with a complex homeopathic immune response modifiers.

INTRODUCTION: Canova is a complex homeopathic medicine that enhances a specific immunologic responses against several exogenous and endogenous conditions. Canova activates macrophages both in vivo and in vitro. AIM AND METHOD: We evaluated the effects of macrophages activated by Canova in vivo and ex vitro in the proliferation of lymphocytes. Canova was used to activate Cebus apella macrophages in vivo or ex vitro with Canova. Lymphocytes were cultured with the macrophage culture medium. The analysis of Canova effects in cultured lymphocytes was performed according to the cell cycle phase using flow cytometry. The Interferon gamma and Interleukin-5 cytokines quantification in these lymphocyte culture media was performed by Enzyme-linked immunosorbent assay (ELISA). RESULTS: We observed that Canova actives macrophages in vivo and ex vitro. The lymphocytes cultured in a supplemented medium with macrophages activated by Canova treatment presented a higher number of proliferation cells than lymphocytes not exposed to macrophages activated by Canova. The Interferon gamma and Interleukin-5 cytokines were only observed in the medium of lymphocytes exposed to macrophages activated by Canova. Thus, Canova has potential as a new adjuvant therapy.