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1.
Nat Commun ; 11(1): 1133, 2020 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-32111833

RESUMO

Understanding the principles of neuronal connectivity requires tools for efficient quantification and visualization of large datasets. The primate cortex is particularly challenging due to its complex mosaic of areas, which in many cases lack clear boundaries. Here, we introduce a resource that allows exploration of results of 143 retrograde tracer injections in the marmoset neocortex. Data obtained in different animals are registered to a common stereotaxic space using an algorithm guided by expert delineation of histological borders, allowing accurate assignment of connections to areas despite interindividual variability. The resource incorporates tools for analyses relative to cytoarchitectural areas, including statistical properties such as the fraction of labeled neurons and the percentage of supragranular neurons. It also provides purely spatial (parcellation-free) data, based on the stereotaxic coordinates of 2 million labeled neurons. This resource helps bridge the gap between high-density cellular connectivity studies in rodents and imaging-based analyses of human brains.


Assuntos
Atlas como Assunto , Encéfalo/anatomia & histologia , Callithrix/anatomia & histologia , Animais , Encéfalo/metabolismo , Encéfalo/fisiologia , Mapeamento Encefálico , Callithrix/fisiologia , Imageamento Tridimensional , Neocórtex/citologia , Neocórtex/metabolismo , Neocórtex/fisiologia , Vias Neurais , Marcadores do Trato Nervoso/administração & dosagem , Marcadores do Trato Nervoso/metabolismo , Neurônios/citologia , Neurônios/metabolismo , Neurônios/fisiologia
2.
Rev Soc Bras Med Trop ; 53: e20190402, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32187339

RESUMO

In Brazil, rabies occurs mainly within an urban cycle, in which dogs and bats are reservoirs. This paper aims to report the occurrence of rabies in Callithrix sp. in Niterói, Rio de Janeiro, Brazil. In June 2019 a hybrid specimen was referred for diagnosis. The Direct Fluorescent Antibody, Mouse Inoculation, and Polymerase Chain Reaction tests were positive. A phylogenetic analysis was compatible with antigenic variant 3, characteristic of Desmodus rotundus. New studies should be undertaken to elucidate the real role of callitrichids in the urban rabies cycle.


Assuntos
Callithrix/virologia , Vírus da Raiva/genética , Raiva/diagnóstico , Animais , Brasil , Técnica Direta de Fluorescência para Anticorpo , Filogenia , Reação em Cadeia da Polimerase , Vírus da Raiva/imunologia , População Urbana
3.
PLoS Comput Biol ; 16(2): e1007627, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32069272

RESUMO

In primary auditory cortex, slowly repeated acoustic events are represented temporally by the stimulus-locked activity of single neurons. Single-unit studies in awake marmosets (Callithrix jacchus) have shown that a sub-population of these neurons also monotonically increase or decrease their average discharge rate during stimulus presentation for higher repetition rates. Building on a computational single-neuron model that generates stimulus-locked responses with stimulus evoked excitation followed by strong inhibition, we find that stimulus-evoked short-term depression is sufficient to produce synchronized monotonic positive and negative responses to slowly repeated stimuli. By exploring model robustness and comparing it to other models for adaptation to such stimuli, we conclude that short-term depression best explains our observations in single-unit recordings in awake marmosets. Together, our results show how a simple biophysical mechanism in single neurons can generate complementary neural codes for acoustic stimuli.


Assuntos
Córtex Auditivo/fisiologia , Callithrix/fisiologia , Estimulação Acústica , Adaptação Fisiológica , Animais , Potenciais Evocados Auditivos/fisiologia
4.
PLoS Negl Trop Dis ; 14(2): e0008027, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32049958

RESUMO

Zika virus (ZIKV) has spread in many countries or territories causing severe neurologic complications with potential fatal outcomes. The small primate common marmosets are susceptible to ZIKV, mimicking key features of human infection. Here, a novel simian adenovirus type 23 vector-based vaccine expressing ZIKV pre-membrane-envelope proteins (Sad23L-prM-E) was produced in high infectious titer. Due to determination of immunogenicity in mice, a single-dose of 3×108 PFU Sad23L-prM-E vaccine was intramuscularly inoculated to marmosets. This vaccine raised antibody titers of 104.07 E-specific and 103.13 neutralizing antibody (NAb), as well as robust specific IFN-γ secreting T-cell response (1,219 SFCs/106 cells) to E peptides. The vaccinated marmosets, upon challenge with a high dose of ZIKV (105 PFU) six weeks post prime immunization, reduced viremia by more than 100 folds, and the low level of detectable viral RNA (<103 copies/ml) in blood, saliva, urine and feces was promptly eliminated when the secondary NAb (titer >103.66) and T-cell response (>726 SFCs/106 PBMCs) were acquired 1-2 weeks post exposure to ZIKV, while non-vaccinated control marmosets developed long-term high titer of ZIKV (105.73 copies/ml) (P<0.05). No significant pathological lesions were observed in marmoset tissues. Sad23L-prM-E vaccine was detectable in spleen, liver and PBMCs at least 4 months post challenge. In conclusion, a prime immunization with Sad23L-prM-E vaccine was able to protect marmosets against ZIKV infection when exposed to a high dose of ZIKV. This Sad23L-prM-E vaccine is a promising vaccine candidate for prevention of ZIKV infection in humans.


Assuntos
Infecções por Adenoviridae/veterinária , Adenovirus dos Símios/classificação , Callithrix , Doenças dos Macacos/virologia , Infecção por Zika virus/veterinária , Infecções por Adenoviridae/imunologia , Infecções por Adenoviridae/virologia , Animais , Doenças dos Macacos/imunologia , Infecção por Zika virus/imunologia
5.
Nat Commun ; 11(1): 301, 2020 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-31949148

RESUMO

Speciation is associated with substantial rewiring of the regulatory circuitry underlying the expression of genes. Determining which changes are relevant and underlie the emergence of the human brain or its unique susceptibility to neural disease has been challenging. Here we annotate changes to gene regulatory elements (GREs) at cell type resolution in the brains of multiple primate species spanning most of primate evolution. We identify a unique set of regulatory elements that emerged in hominins prior to the separation of humans and chimpanzees. We demonstrate that these hominin gains perferentially affect oligodendrocyte function postnatally and are preferentially affected in the brains of autism patients. This preference is also observed for human-specific GREs suggesting this system is under continued selective pressure. Our data provide a roadmap of regulatory rewiring across primate evolution providing insight into the genomic changes that underlie the emergence of the brain and its susceptibility to neural disease.


Assuntos
Transtorno Autístico/metabolismo , Encéfalo/metabolismo , Hominidae/metabolismo , Oligodendroglia/metabolismo , Sequências Reguladoras de Ácido Nucleico/fisiologia , Animais , Transtorno Autístico/genética , Callithrix , Cromatina , Imunoprecipitação da Cromatina , Cromossomos/química , Suscetibilidade a Doenças , Evolução Molecular , Feminino , Regulação da Expressão Gênica , Genômica , Hominidae/genética , Humanos , Macaca mulatta , Pan troglodytes
6.
Nat Neurosci ; 23(2): 271-280, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31932765

RESUMO

While the fundamental importance of the white matter in supporting neuronal communication is well known, existing publications of primate brains do not feature a detailed description of its complex anatomy. The main barrier to achieving this is that existing primate neuroimaging data have insufficient spatial resolution to resolve white matter pathways fully. Here we present a resource that allows detailed descriptions of white matter structures and trajectories of fiber pathways in the marmoset brain. The resource includes: (1) the highest-resolution diffusion-weighted MRI data available to date, which reveal white matter features not previously described; (2) a comprehensive three-dimensional white matter atlas depicting fiber pathways that were either omitted or misidentified in previous atlases; and (3) comprehensive fiber pathway maps of cortical connections combining diffusion-weighted MRI tractography and neuronal tracing data. The resource, which can be downloaded from marmosetbrainmapping.org, will facilitate studies of brain connectivity and the development of tractography algorithms in the primate brain.


Assuntos
Mapeamento Encefálico/métodos , Encéfalo/anatomia & histologia , Substância Branca/anatomia & histologia , Animais , Callithrix , Imageamento Tridimensional
7.
Immunity ; 52(1): 167-182.e7, 2020 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-31883839

RESUMO

Multiple sclerosis (MS) is a demyelinating, autoimmune disease of the central nervous system. While work has focused on myelin and axon loss in MS, less is known about mechanisms underlying synaptic changes. Using postmortem human MS tissue, a preclinical nonhuman primate model of MS, and two rodent models of demyelinating disease, we investigated synapse changes in the visual system. Similar to other neurodegenerative diseases, microglial synaptic engulfment and profound synapse loss were observed. In mice, synapse loss occurred independently of local demyelination and neuronal degeneration but coincided with gliosis and increased complement component C3, but not C1q, at synapses. Viral overexpression of the complement inhibitor Crry at C3-bound synapses decreased microglial engulfment of synapses and protected visual function. These results indicate that microglia eliminate synapses through the alternative complement cascade in demyelinating disease and identify a strategy to prevent synapse loss that may be broadly applicable to other neurodegenerative diseases. VIDEO ABSTRACT.


Assuntos
Complemento C3/imunologia , Encefalomielite Autoimune Experimental/patologia , Microglia/patologia , Esclerose Múltipla/patologia , Sinapses/patologia , Tálamo/patologia , Idoso , Idoso de 80 Anos ou mais , Animais , Callithrix , Linhagem Celular Tumoral , Complemento C3/antagonistas & inibidores , Modelos Animais de Doenças , Feminino , Gliose/patologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Receptores de Complemento 3b/metabolismo
8.
Nat Commun ; 10(1): 4592, 2019 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-31597928

RESUMO

Across vertebrates, progressive changes in vocal behavior during postnatal development are typically attributed solely to developing neural circuits. How the changing body influences vocal development remains unknown. Here we show that state changes in the contact vocalizations of infant marmoset monkeys, which transition from noisy, low frequency cries to tonal, higher pitched vocalizations in adults, are caused partially by laryngeal development. Combining analyses of natural vocalizations, motorized excised larynx experiments, tensile material tests and high-speed imaging, we show that vocal state transition occurs via a sound source switch from vocal folds to apical vocal membranes, producing louder vocalizations with higher efficiency. We show with an empirically based model of descending motor control how neural circuits could interact with changing laryngeal dynamics, leading to adaptive vocal development. Our results emphasize the importance of embodied approaches to vocal development, where exploiting biomechanical consequences of changing material properties can simplify motor control, reducing the computational load on the developing brain.


Assuntos
Callithrix/fisiologia , Laringe/fisiologia , Prega Vocal/fisiologia , Vocalização Animal/fisiologia , Algoritmos , Animais , Animais Recém-Nascidos , Callithrix/crescimento & desenvolvimento , Feminino , Laringe/crescimento & desenvolvimento , Masculino , Modelos Biológicos , Ruído , Som , Prega Vocal/crescimento & desenvolvimento
9.
Molecules ; 24(17)2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31480595

RESUMO

Pyrrole-imidazole (PI) polyamides are novel gene silencers that strongly bind the promoter region of target genes in a sequence-specific manner to inhibit gene transcription. We created a PI polyamide targeting human TGF-ß1 (hTGF-ß1). To develop this PI polyamide targeting hTGF-ß1 (Polyamide) as a practical medicine for treating progressive renal diseases, we examined the effects of Polyamide in two common marmoset models of nephropathy. We performed lead optimization of PI polyamides that targeted hTGF-ß1 by inhibiting in a dose-dependent manner the expression of TGF-ß1 mRNA stimulated by PMA in marmoset fibroblasts. Marmosets were housed and fed with a 0.05% NaCl and magnesium diet and treated with cyclosporine A (CsA; 37.5 mg/kg/day, eight weeks) to establish chronic nephropathy. We treated the marmosets with nephropathy with Polyamide (1 mg/kg/week, four weeks). We also established a unilateral urethral obstruction (UUO) model to examine the effects of Polyamide (1 mg/kg/week, four times) in marmosets. Histologically, the renal medulla from CsA-treated marmosets showed cast formation and interstitial fibrosis in the renal medulla. Immunohistochemistry showed strong staining of Polyamide in the renal medulla from CsA-treated marmosets. Polyamide treatment (1 mg/kg/week, four times) reduced hTGF-ß1 staining and urinary protein excretion in CsA-treated marmosets. In UUO kidneys from marmosets, Polyamide reduced the glomerular injury score and tubulointerstitial injury score. Polyamide significantly suppressed hTGF-ß1 and snail mRNA expression in UUO kidneys from the marmosets. Polyamide effectively improved CsA- and UUO-associated nephropathy, indicating its potential application in the prevention of renal fibrosis in progressive renal diseases.


Assuntos
DNA/metabolismo , Imidazóis/farmacologia , Nefropatias/genética , Nylons/farmacologia , Peptídeos/metabolismo , Regiões Promotoras Genéticas , Pirróis/farmacologia , Fator de Crescimento Transformador beta1/genética , Animais , Sequência de Bases , Caderinas/metabolismo , Callithrix , Ciclosporina , Fibrose , Humanos , Rim/efeitos dos fármacos , Rim/patologia , Nefropatias/patologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fatores de Transcrição da Família Snail/genética , Fatores de Transcrição da Família Snail/metabolismo , Obstrução Uretral/genética , Obstrução Uretral/patologia
10.
Brain Behav Evol ; 93(2-3): 92-107, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31416070

RESUMO

The common marmoset, a New World (platyrrhine) monkey, is currently being fast-tracked as a non-human primate model species, especially for genetic modification but also as a general-purpose model for research on the brain and behavior bearing on the human condition. Compared to the currently dominant primate model, the catarrhine macaque monkey, marmosets are notable for certain evolutionary specializations, including their propensity for twin births, their very small size (a result of phyletic dwarfism), and features related to their small size (rapid development and relatively short lifespan), which result in these animals yielding experimental results more rapidly and at lower cost. Macaques, however, have their own advantages. Importantly, macaques are more closely related to humans (which are also catarrhine primates) than are marmosets, sharing approximately 20 million more years of common descent, and are demonstrably more similar to humans in a variety of genomic, molecular, and neurobiological characteristics. Furthermore, the very specializations of marmosets that make them attractive as experimental subjects, such as their rapid development and short lifespan, are ways in which marmosets differ from humans and in which macaques more closely resemble humans. These facts warrant careful consideration of the trade-offs between convenience and cost, on the one hand, and biological realism, on the other, in choosing between non-human primate models of human biology. Notwithstanding the advantages marmosets offer as models, prudence requires continued commitment to research on macaques and other primate species.


Assuntos
Evolução Biológica , Callithrix/anatomia & histologia , Macaca/anatomia & histologia , Modelos Animais , Sistema Nervoso/anatomia & histologia , Animais , Callithrix/fisiologia , Macaca/fisiologia
12.
Nat Commun ; 10(1): 3796, 2019 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-31439849

RESUMO

Marmosets have attracted significant interest in the life sciences. Similarities with human brain anatomy and physiology, such as the granular frontal cortex, as well as the development of transgenic lines and potential for transferring rodent neuroscientific techniques to small primates make them a promising neurodegenerative and neuropsychiatric model system. However, whether marmosets can exhibit complex motor tasks in highly controlled experimental designs-one of the prerequisites for investigating higher-order control mechanisms underlying cognitive motor behavior-has not been demonstrated. We show that marmosets can be trained to perform vocal behavior in response to arbitrary visual cues in controlled operant conditioning tasks. Our results emphasize the marmoset as a suitable model to study complex motor behavior and the evolution of cognitive control underlying speech.


Assuntos
Encéfalo/fisiologia , Callithrix/fisiologia , Condicionamento Operante/fisiologia , Vocalização Animal/fisiologia , Animais , Cognição , Feminino , Masculino , Modelos Animais
13.
Elife ; 82019 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-31310236

RESUMO

In adult animals, movement and vocalizations are coordinated, sometimes facilitating, and at other times inhibiting, each other. What is missing is how these different domains of motor control become coordinated over the course of development. We investigated how postural-locomotor behaviors may influence vocal development, and the role played by physiological arousal during their interactions. Using infant marmoset monkeys, we densely sampled vocal, postural and locomotor behaviors and estimated arousal fluctuations from electrocardiographic measures of heart rate. We found that vocalizations matured sooner than postural and locomotor skills, and that vocal-locomotor coordination improved with age and during elevated arousal levels. These results suggest that postural-locomotor maturity is not required for vocal development to occur, and that infants gradually improve coordination between vocalizations and body movement through a process that may be facilitated by arousal level changes.


Assuntos
Percepção Auditiva , Sistema Nervoso Autônomo/fisiologia , Córtex Cerebral/fisiologia , Movimento , Desempenho Psicomotor , Vocalização Animal , Animais , Callithrix , Eletrocardiografia , Feminino , Frequência Cardíaca , Masculino
14.
J Toxicol Sci ; 44(7): 441-457, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31270301

RESUMO

The objective of this study is to assess the response of telemetered common marmosets to multiple cardiac ion channel inhibitors and to clarify the usefulness of this animal model in evaluating the effects of drug candidates on electrocardiogram (ECG). Six multiple cardiac ion channel inhibitors (sotalol, astemizole, flecainide, quinidine, verapamil and terfenadine) were orally administered to telemetered common marmosets and changes in QTc, PR interval and QRS duration were evaluated. Drugs plasma levels were determined to compare the sensitivity in common marmosets to that in humans. QTc prolongation was observed in the marmosets dosed with sotalol, astemizole, flecainide, quinidine, verapamil and terfenadine. PR prolongation was noted after flecainide and verapamil administration, and QRS widening occurred following treatment with flecainide and quinidine. Drugs plasma levels associated with ECG changes in marmosets were similar to those in humans, except for verapamil-induced QTc prolongation. Verapamil-induced change is suggested due to body temperature decrease. These results indicate that telemetered common marmoset is a useful animal for evaluation of the ECG effects of multiple cardiac ion channel inhibitors and the influence of body temperature change should be considered in the assessment.


Assuntos
Astemizol/farmacologia , Bloqueadores dos Canais de Cálcio/farmacologia , Callithrix , Eletrocardiografia/efeitos dos fármacos , Flecainida/farmacologia , Modelos Animais , Quinidina/farmacologia , Medição de Risco/métodos , Sotalol/farmacologia , Telemetria , Terfenadina/farmacologia , Verapamil/farmacologia , Bloqueadores do Canal de Sódio Disparado por Voltagem/farmacologia , Animais , Astemizol/sangue , Temperatura Corporal/fisiologia , Bloqueadores dos Canais de Cálcio/sangue , Flecainida/sangue , Masculino , Quinidina/sangue , Sotalol/sangue , Terfenadina/sangue , Verapamil/sangue , Bloqueadores do Canal de Sódio Disparado por Voltagem/sangue
15.
Behav Processes ; 167: 103899, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31326510

RESUMO

Specialization of the left and right hemispheres to control behavioural responses may represent one of the mechanisms underlying individual differences in personality structure, as well as the preferential use of one hand. The present study investigated the relationship between personality and hand preference in common marmosets (Callithrix jacchus), a little New World monkey that presents highly consistent and stable individual hand preferences for simple reaching. To address this issue, data on 56 different behaviours from the species' behavioural repertoire were measured in 10 different laboratory tests and during observations under social conditions on 16 adult common marmosets. Stable behavioural variables were aggregated a priori into 13 personality traits. Exploratory Factor Analysis (EFA) on personality traits was carried out to verify the presence of major personality factors, and their relationship with direction and strength of individual hand preferences was assessed by multiple regression, taking into account sex and age of the subjects. The largest number of species-specific behaviours so far investigated in this species was taken into account and robust temporal stability between two testing periods was verified. We confirm that common marmosets are characterized by specific and stable personality profiles. A single personality factor, accounting for about 38% of the total variance, was found by EFA, that describes the interest towards unusual and new experiences and resembles the human Openness domain. The strength of the hand preference was found to be predicted by this personality factor, that we named Inquisitiveness. Present results highlight common marmoset as a useful primate model for the study of the relationship between personality and lateralization.


Assuntos
Comportamento Animal/fisiologia , Callithrix/psicologia , Lateralidade Funcional/fisiologia , Personalidade/fisiologia , Animais , Callithrix/fisiologia , Feminino , Individualidade , Masculino
16.
Yakugaku Zasshi ; 139(7): 1007-1013, 2019.
Artigo em Japonês | MEDLINE | ID: mdl-31257247

RESUMO

α-Synuclein (αS) is the major component of the filamentous inclusions that constitute the defining characteristic of neurodegenerative synucleinopathies, including Parkinson's disease, dementia with Lewy bodies, and multiple system atrophy. αS is deposited in a hyperphosphorylated and ubiquitinated form with a ß-sheet-rich fibrillar structure in diseased brains. In 2008, some researchers reported that embryonic neurons transplanted into Parkinson's disease brains had Lewy body-like pathologies, suggesting that pathological αS propagates from diseased neurons to young neurons. Subsequently, a growing body of evidence supported the cell-to-cell spread of αS pathologies. Recent studies have revealed that intracerebral injection of insoluble αS into wild-type mice can induce prion-like propagation of phosphorylated αS pathology even 1 month after injection, while injection into αS-knockout mice failed to induce any pathology. We also showed that intracerebral injection of insoluble αS into adult common marmoset brains results in the spreading of abundant αS pathology. These in vivo experiments clearly indicate that insoluble αS has prion-like properties and that it propagates through neural networks. The underlying mechanisms of αS propagation are still poorly understood, but αS propagation model animals could be helpful in elucidating the pathogenetic mechanisms and developing drugs for synucleinopathies.


Assuntos
Doenças Neurodegenerativas/metabolismo , Agregação Patológica de Proteínas , alfa-Sinucleína/metabolismo , Animais , Encéfalo/metabolismo , Callithrix , Humanos , Doença por Corpos de Lewy , Camundongos , Doenças Neurodegenerativas/etiologia , Doença de Parkinson , Fosforilação , Príons
18.
Int J Syst Evol Microbiol ; 69(8): 2477-2485, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31180316

RESUMO

A novel Bifidobacterium strain, MRM 9.3T, was isolated from a faecal sample of a baby common marmoset (Callithrixjacchus). Cells were Gram-stain-positive, non-motile, non-sporulating, non-haemolytic, facultatively anaerobic and fructose 6-phosphate phosphoketolase-positive. Phylogenetic analyses based on 16S rRNA genes as well as multilocus sequences (representing hsp60, rpoB, clpC, dnaJ and dnaG genes) and the core genomes revealed that strain MRM 9.3T exhibited phylogenetic relatedness to Bifidobacterium myosotis DSM 100196T. Comparative analysis of 16S rRNA gene sequences confirmed the phylogenetic results showing the highest gene sequence identity with strain B.ifidobacterium myosotis DSM 100196T (95.6 %). The average nucleotide identity, amino acid average identity and in silico DNA-DNA hybridization values between MRM 9.3T and DSM 100196T were 79.9, 72.1 and 28.5 %, respectively. Phenotypic and genotypic features clearly showed that the strain MRM 9.3T represents a novel species, for which the name Bifidobacterium jacchi sp. nov. is proposed. The type strain is MRM 9.3T (=DSM 103362T =JCM 31788T).


Assuntos
Bifidobacterium/classificação , Callithrix/microbiologia , Fezes/microbiologia , Filogenia , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , Bifidobacterium/isolamento & purificação , DNA Bacteriano/genética , Ácidos Graxos/química , Genes Bacterianos , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
19.
Invest Ophthalmol Vis Sci ; 60(7): 2623-2630, 2019 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-31226711

RESUMO

Purpose: To explore the effect of topical atropine on axial eye growth and emmetropization in infant marmosets. Methods: Atropine was applied to one eye from the age of 7 to 56 days in two dose regimens, High (0.1-1% twice daily, increasing with age) or moderate (Mod) (0.1% once daily). Both eyes of the marmosets were refracted, and axial dimensions were measured ultrasonically, at 14, 28, 42, 49, 56, 70, 105, 168, and 279 days of age. The time course of each measured variable was analyzed using multilevel mixed-effects modeling realized in R. Results: The logistic growth curves fitted to anterior segment depth (ASD) did not differ significantly between the dose regimens, but xmid, the age at which growth was half-maximal, and scal, the time constant of the exponential term in the logistic growth curve equation, differed significantly between the ASD of atropinized and untreated eyes (P = 0.03 and P < 0.0001, respectively), with the ASD of atropinized eyes shorter than that of untreated eyes. The splines fitted to lens thickness did not vary significantly with dose, but differed significantly (P < 0.0001) between the atropinized and untreated eyes, with the atropinized lenses thicker. Vitreous chamber depth (VCD) was not significantly different, but the variance of VCD was significantly greater (P < 0.001) in the atropinized compared with the untreated eyes. Refractive error (RE) became relatively myopic in atropinized eyes. The variance of RE in atropinized eyes was significantly greater (P < 0.0001) than in untreated eyes. Conclusions: Atropine caused the infant marmoset lens to move forward and thicken, a relative myopia, and increases in the between-animals variance in VCD, which could be considered a failure of emmetropization.


Assuntos
Atropina/administração & dosagem , Comprimento Axial do Olho/efeitos dos fármacos , Olho/crescimento & desenvolvimento , Antagonistas Muscarínicos/administração & dosagem , Miopia/etiologia , Acomodação Ocular/efeitos dos fármacos , Acomodação Ocular/fisiologia , Administração Oftálmica , Animais , Animais Recém-Nascidos , Callithrix , Emetropia/fisiologia , Masculino , Miopia/fisiopatologia , Soluções Oftálmicas , Retinoscopia , Corpo Vítreo/efeitos dos fármacos
20.
Arq. bras. med. vet. zootec. (Online) ; 71(3): 777-781, May-June 2019. ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1011299

RESUMO

This is the first report of parasitism by Gongylonema sp. in a free-ranging callitrichid from the Atlantic forest of Espírito Santo, Brazil. A juvenile male of Geoffroy's marmoset (Callithrix geoffroyi) was euthanized due to poor prognosis, then necropsied. Samples of the tongue were collected for routine histological processing. Microscopically, there were transversal sections of adult nematodes within the epithelial layer of the mucosa of the tongue. Lingual scraping demonstrated a small number of oval embryonated eggs with a thick capsule. The morphology of the adult parasites and the eggs, associated with its location, were compatible with the Spirurida nematode of the genus Gongylonema. Further studies are needed to evaluate the impact of this parasite on free-ranging callitrichid populations.(AU)


Este é o primeiro relato de parasitismo por Gongylonema sp. em um calitriquídeo de vida livre proveniente da Mata Atlântica do Espírito Santo, Brasil. Um sagui-da-cara-branca (Callithrix geoffroyi), macho, jovem, foi eutanasiado, devido a prognóstico desfavorável, e necropsiado. Fragmentos de língua foram coletados para processamento histológico de rotina. Microscopicamente, havia cortes transversais de nematoides adultos na mucosa da língua. Na raspagem da mucosa da língua, foi observada pequena quantidade de ovos larvados ovais com cápsula espessa. A morfologia do parasita adulto e dos ovos, associada à localização do agente, é compatível com nematoide Spirurida do gênero Gongylonema. São necessários estudos adicionais para avaliar o impacto desse parasito nas populações de calitriquídeos de vida livre.(AU)


Assuntos
Animais , Spiruroidea/isolamento & purificação , Callithrix/parasitologia , Infecções por Spirurida/veterinária , Doenças dos Macacos/parasitologia
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