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OBJECTIVE: To evaluate changes in choroidal thickness in presbyopes, when reading with regular glasses versus choroidal control glasses, in patients with or without Age-Related Macular Degeneration (AMD). METHODS: This was a pilot study on short-term axial length (AL) in 33 eyes of 24 presbyopic patients aged 60 to 80 years, assigned to two age-matched groups, with or without AMD. About them, changes in choroidal thickness were evaluated with ocular biometry through indirect measurements of axial length at baseline, after 20' of reading with conventional lenses, and after another 20' of reading with peripheral hyperopic defocus glasses. The differences in axial length between the three different times were analyzed. RESULTS: In presbyopes without AMD there was a significant axial length shortening of -13.44 microns in the first conventional reading period, which was reversed by 90% with hyperopic defocus lenses, recovering + 12.11 microns by axial lengthening (choroidal thinning, p = 0.03). In patients with AMD, axial shortening was significantly greater than controls, -23.86 microns with conventional lenses (p < 0.001) and they, also increased their axial length with defocus, although this response was smaller in proportion (+ 15.52 microns). CONCLUSION: Reading with positive lenses produces myopic defocus and choroidal thickening in presbyopes with and without AMD but was significantly greater in the latter. Glasses with Choroidal Control Technology reduced thickening during reading. KEY MESSAGES: What is known ⢠Presbyopia spectacles for near produce myopic defocus and choroidal thickening. What is new ⢠There are differences in choroidal thickening during reading between normal subjects and those with age related macular degeneration. ⢠Spectacles with Defocus Choroidal Control Technology reduce choroidal thickening during reading in presbyopes.
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This study aimed to evaluate the effects of early group housing on the performance, health, and behavior of dairy calves during the pre-weaning period using systematic and meta-analysis approaches. Peer-reviewed articles written in English that compared dairy calves individually and group-housed with performance, health, or behavior outcomes were collected from Web of Science, PubMed and CabDirect databases. The resulting articles (n = 850) underwent a PRISMA 4-step appraisal process, resulting in a final sample of 51 articles containing 85 studies. The weighted or standardized mean differences between individually and group [pair or group (with > 2 calves)] housed calves were analyzed for each variable using the Der-Simonian and Laird methods. Heterogeneity between calf housing systems was evaluated by the chi-squared test and I2 statistics. A meta-regression analysis was conducted to identify categorical covariate effects for variables with high heterogeneity. Most of the studies included in this review evaluated female calves (45.8%) weaned at 8 weeks old (52.6%). Housing systems were mainly paired housing (55.3%), followed by groups of 3 to 6 calves (30.65) and groups of 7 to 15 calves (4.7%). We did not find studies with comparable outcomes for more robust health parameters (as occurrence of diseases), only blood parameters, that were not influenced by the housing system (P > 0.05). But, weight gain and feed intake parameters were higher (P < 0.05) in group-housed calves. Through the meta-regression, we found that average daily gain was positively affected (P < 0.05) by the group housing in studies with calves housed in small pen areas (<1.5 m2 per calf). Group-housed calves presented more active behaviors (feeding and playing) and less stress-related behaviors (self-grooming and interacting with the pen) than individually-housed calves. The behavioral tests most used were novel object, human approach, novel environment, and social tests. Individually-housed calves presented fewer vocalizations on these tests and spent more time interacting with humans during the human approach test than group-housed calves. Our findings provide consistent evidence that group housing improves the welfare of dairy calves; however, the effects on health parameters are still scarce and unclear.
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OBJECTIVE: To assess intraocular pressure (IOP) development in cranes and determine the impact of age, weight, species, head position, and sex. ANIMALS STUDIED: Whooping cranes (WC) (Grus americana), and Mississippi-sandhill cranes (MSC) (Grus canadensis pulla). PROCEDURES: Chicks were manually restrained on days 1-3, 7, 21, 35, 60, 75, and 120 for routine examinations. IOP was opportunistically measured utilizing the Tonovet Plus® in D setting with the head above the heart (AH) and below the heart (BH). Values were also obtained longitudinally in adults (>120 days old) upon presentation in 1 year. RESULTS: Intraocular pressure was highly correlated with age and weight in chicks. For every kilogram gained, IOP increased 2.46 ± 0.08 mmHg in WC and 2.66 ± 0.11 mmHg in MSC. Once hatched, IOP increased 1.13 ± 0.04 mmHg in WC and 0.87 ± 0.04 mmHg in MSC every 10 days. IOP was similar to adults at 120 days of age. In adult WC, mean IOP AH was 24.0 ± 0.4 mmHg, and BH was 27.9 ± 0.4 mmHg, there was a significant difference regarding head positioning and sex, females (25.3 ± 0.4 mm Hg) had lower IOP than males (26.5 ± 0.4 mmHg). In adult MSC, mean IOP AH was 20.7 ± 0.4 mmHg, and BH was 24.6 ± 0.4 mmHg. The difference between head positioning was significant. CONCLUSIONS: This study documents the correlation between IOP and weight or age during early development in cranes, as well as the importance of head positioning.
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OBJECTIVE: To establish baseline ophthalmic parameters for an endangered, semi-wild population of healthy whooping cranes (Grus americana) (WHCR) and Mississippi sandhill cranes (Grus canadensis pulla) (SACR). ANIMALS STUDIED: Eighteen WHCR and 16 SACR. PROCEDURES: Ophthalmic examination was performed by a single observer, followed by conjunctival swab collection for aerobic bacterial culture and measurement of tear production (phenol red thread test, PRTT) and corneal diameter (CD) as tolerated. Measurement of the axial globe (AG) length, anterior chamber (AC) depth, lens thickness, vitreous chamber (VC) depth, and pecten length was performed via ocular ultrasound (OUS) as tolerated. RESULTS: Eyelid cicatrization (n = 1 WHCR), keratitis (n = 2 WHCR), incipient cataracts (n = 1 WHCR, n = 4 SACR), and uveal cysts (n = 1 SACR) were identified. Twenty-one bacterial species were cultured from SACR, while 18 bacterial species were cultured from WHCR. SACR under 6 months old had increased PRTT values compared to older SACR (p = .0432). AG length and VC depth of male WHCR were greater than in female WHCR (p = .0045 and p = .0008, respectively). WHCR less than 6 months old had greater AC depth and lens thickness than WHCR over 6 months (p < .001 and p = .0013, respectively). SACR less than 6 months old had greater AC depth and lens thickness than WHCR over 6 months (p < .0001 and p < .0001, respectively). CONCLUSIONS: WHCR and SACR are amenable to complete ophthalmic examination. Age-related differences in PRTT in SACR, sexual dimorphism in WHCR, and age-related differences in AC depth and lens thickness in WHCR and SACR were identified.
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This meta-analysis aims to investigate the effects of residual feed intake (RFI) phenotype on performance, nutrient utilization and meat quality traits in Zebu (Bos indicus) cattle. Twenty-three peer-reviewed publications with 37 treatment means were included in the dataset. Weighted mean difference analysis compared animals categorized into low RFI (more efficient) versus medium or high RFI (less efficient) groups. Data heterogeneity via meta-regression and subgroup analysis, considering variables such as animal age, sex class, experimental duration, RFI group, dietary concentrate, and estimated metabolizable energy intake were also explored. The predominant genetic group of cattle in the dataset was Nellore (89.18%), followed by Brahman (10.81%). More efficient animals (low RFI phenotype) exhibited less dry matter intake (DMI; P < 0.010) than medium or high RFI animals (-0.95 kg vs. -0.42 kg/d). Cattle dietary crude protein and fiber digestibility were consistent across RFI groups (P > 0.05), while dietary ether extract digestibility tended to decrease (P = 0.050) in low RFI animals (-13.20 g/kg DM). Low RFI animals tended to increased (P = 0.065) ribeye area (REA) compared to the high/medium RFI groups, while carcass backfat thickness (BFT) decreased (P = 0.042) compared to high/medium RFI groups. Moreover, there was an increase (P < 0.001) of 0.22 kg in Warner-Bratzler shear force (WBSF) and a reduction (P < 0.001) in the myofibrillar fragmentation index (MFI) in low RFI animals. Meat color parameters (lightness [L*] and yellowness [b*]) and visual marbling scores were consistent (P > 0.05) across RFI groups. In conclusion, Zebu cattle classified as efficient (low RFI) exhibited reduced DMI, which improves their feed efficiency. However, BFT and meat quality parameters such as tenderness (WBSF and MFI) and redness [a*] were compromised by low RFI phenotype, highlighting the challenge of enhancing feed efficiency and meat quality traits in Zebu cattle.
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Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Dieta , Animais , Bovinos/fisiologia , Feminino , Masculino , Ração Animal/análise , Dieta/veterinária , Fenótipo , Carne Vermelha/análiseRESUMO
The asymptomatic and slow progressive nature of cardiopathies represents a risk to the welfare of avian species in human care. Diagnosis and treatment of cardiac disease in birds pose a challenge due to unique anatomic and physiologic characteristics. Comprehensive cardiac assessments with diagnostic tools such as echocardiography, color-Doppler, the biomarker cardiac troponin I (cTn1), and cholesterol serum concentrations have been utilized in different bird species with varying success. Saddle-billed storks (Ephippiorhynchus senegalensis) have been maintained in human care for over 80 yrs and several institutions have noted heart murmurs and cardiomegaly. Despite these findings, peer-reviewed literature describing cardiopathies is lacking for this species. This case series documents the identification of mitral valve regurgitation in saddle-billed storks in a breeding center. Transcoelomic echocardiography using a ventromedial approach with a two-chambered view and color Doppler was utilized. Echocardiographic measurements were taken and compared 1 yr later in most of the birds. There was left atrial enlargement and worsened mitral regurgitation in one geriatric patient, and no progression of the disease in two young birds. Serum samples showed that cTn1 had different concentrations depending on the severity of the disease, whereas cholesterol was within reference range for all birds. Treatment with digoxin and pimobendan was recommended in one bird, serum concentrations of digoxin were tested in a 6-mon span, results were within therapeutic range, and there were no overt adverse effects. There was a suspected genetic component in this population, as four of the five birds with confirmed mitral regurgitation were related.
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Insuficiência da Valva Mitral , Animais , Humanos , Insuficiência da Valva Mitral/diagnóstico , Insuficiência da Valva Mitral/veterinária , Aves , Ecocardiografia/veterinária , Digoxina , ColesterolRESUMO
Molasses must be one of the most used foods in the diet of ruminant animals; however, there is no consensus on the effect of including molasses on carcass parameters. In this context, the objective was to evaluate the effect of including molasses in the diet of feedlot cattle on performance and carcass parameters. Thirteen peer-reviewed publications with 45 treatment means were included in the dataset. The effect of molasses in beef cattle diets was evaluated by examining the weighted mean differences (WMD) between molasses treatment (diet with molasses) and control diet (diet without molasses). Heterogeneity was explored by meta-regression and subgroup analysis using genetic type and experimental period, molasses in diet (g/kg dry matter (DM)), molasses type, concentrate in diet (g/kg DM), and forage type. The inclusion of molasses in the diet increased dry matter digestibility, but reduced NDF digestibility, carcass weight, subcutaneous, and visceral fat. The main sources of variation for the responses with molasses inclusion on intake, digestibility, performance, and carcass parameters were the level of molasses inclusion and the experimental period. In general context, the inclusion of molasses in the diet between 100 to 150 g/kg of DM did not affect performance and carcass parameters. However, the inclusion of molasses above 200 g/kg reduces the average daily gain and carcass weight.
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Ração Animal , Zea mays , Bovinos , Animais , Ração Animal/análise , Melaço , Digestão , Dieta/veterinária , Suplementos NutricionaisRESUMO
Chronic enteropathies pose an important difficulty in the captive management of cheetahs (Acinonyx jubatus) because of suspected multifactorial pathogenesis and the complex nature of enteric microbiota dynamics. Enterobacteriaceae, Campylobacter spp., Clostridium perfringens, Helicobacter spp., and Salmonella spp. are enteropathogens of interest because of their zoonotic potential and suspected contribution to enteropathies. This study aimed to determine the presence of these enteropathogens of interest in fecal samples from cheetahs (N = 48) fed different diets from three different institutions and to investigate the associations between diet, fecal score, and specific enteropathogen presence. Fluorescence in situ hybridization (FISH) with rRNA-targeted oligonucleotide probes were used to visualize and quantify putative enteropathogens in each sample concurrent with selective culturing for Salmonella and Clostridium perfringens. From FISH counts, carcass-fed animals had greater numbers of Enterobacteriaceae compared with animals fed low-fat dog food, although this trend was not statistically significant (P = 0.088). Furthermore, no significant associations were found between fecal score and bacterial load. Abundance of Campylobacter spp., Clostridium perfringens, or Helicobacter spp. as measured by FISH were not correlated with diet or fecal score. On the basis of these data, in agreement with published literature, it is concluded that these microbes may be commensals in the cheetah gastrointestinal tract and do not appear to be a primary cause of abnormal fecal scores.
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Acinonyx , Animais , Cães , Hibridização in Situ Fluorescente/veterinária , Dieta/veterinária , Fezes , Trato Gastrointestinal , Salmonella , Animais de ZoológicoRESUMO
Protective antibody titers against core vaccines have not been standardized for cheetahs (Acinonyx jubatus) under human care. Vaccine-induced disease has been suspected after administration of modified live virus vaccine (MLVV), but it has not been confirmed as the causative agent. MLVV and killed virus vaccines (KVV) elicit humoral response in cheetahs; however, the use of both vaccines for initial immunization in cheetah cubs <6 months old within the same population has not been reported. The current case series describes viral disease presentation in two cheetah litters after using both vaccines and presents results for serum neutralization titers against feline calicivirus (FCV) and feline herpesvirus-1 (FHV-1) and hemagglutination inhibition titers against feline panleukopenia virus (FPV). For Litter 1, MLVV was administered at 6 and 9 wk old. On week 11, one male developed ocular, oral, and dermal lesions. Viral isolation recovered FCV. Because of suspected vaccine-induced FCV, KVV was administered on weeks 13 and 16. Litter 2 was vaccinated with KVV via the same vaccination schedule. Fifty-three days after the last booster, two cubs presented with ocular, respiratory, and oral clinical signs; both were PCR positive for FHV-1. Serology reported a better anamnestic response and protective titers against FCV and FPV with the protocol used with Litter 1. In Litter 2, FCV and FHV-1 titer measurement failed in three of four cubs, limiting comparison of titers between litters. In spite of limited measurements, absence of a statistical evaluation, and presence of infection, serology showed a better humoral response when MLVV was used.
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Acinonyx , Calicivirus Felino , Doenças do Gato , Vacinas Atenuadas , Vacinas Virais , Viroses , Animais , Gatos , Humanos , Masculino , Anticorpos Antivirais , Vírus da Panleucopenia Felina , Vacinas Atenuadas/efeitos adversos , Vacinas de Produtos Inativados , Varicellovirus , Vacinas Virais/efeitos adversos , Viroses/prevenção & controle , Viroses/veterináriaRESUMO
Increasing attention has been drawn to the role that intracellular calcium stores play in neuronal function. Ryr3 is an intracellular calcium channel that contributes to hippocampal long-term potentiation, dendritic spine function, and higher cognitive processes. Interestingly, stimuli that increase neuronal activity upregulate the transcriptional activity of Ryr3 and augment DNA methylation in its proximal promoter. However, if these observations are valid for complex behavioral tasks such as learning and memory remains being evaluated. Relative expression analysis revealed that spatial learning increased the hippocampal levels of Ryr3, whereas mice trained using a visible platform that resulted in no spatial association showed reduced expression. Interestingly, we also observed that specific DNA modifications accompanied these opposite transcriptional changes. Increased DNA methylation was observed in hippocampal samples from spatially trained mice, and increased DNA hydroxymethylation was found in samples from mice trained using a visible platform. Both DNA modifications were not altered in control regions, suggesting that these changes are not generalized, but rather specific modifications associated with this calcium channel's transcriptional regulation. Our two experimental groups underwent the same physical task differing only in the spatial learning component, highlighting the tight relationship between DNA modifications and transcriptional activity in a relevant context such as behavioral training. Our results complement previous observations and suggest that DNA modifications are a reliable signal for the transcriptional activity of Ryr3 and can be useful to understand how conditions such as aging and neuropathological diseases determine altered Ryr3 expression.
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Sinalização do Cálcio/fisiologia , Metilação de DNA , Hipocampo/metabolismo , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Aprendizagem Espacial/fisiologia , Animais , Cálcio/metabolismo , Camundongos , Neurônios/metabolismo , Canal de Liberação de Cálcio do Receptor de Rianodina/genéticaRESUMO
Cefovecin is a third-generation cephalosporin with potential value for use in exotic felids due to its long duration of action. A sparse sampling protocol was implemented with 18 zoo-housed cheetahs (Acinonyx jubatus) to evaluate the pharmacokinetics of cefovecin (Convenia® ) after a single 8 mg/kg intramuscular injection. Blood was collected serially for 15 days following administration, and plasma cefovecin concentrations were determined using high-pressure liquid chromatography with ultraviolet detection. Pharmacokinetic parameters were estimated using population pharmacokinetic methods and non-linear mixed effects modeling (NLME). Cefovecin was well tolerated by all cats, with no adverse effects observed. Peak plasma cefovecin concentration was 84.75 µg/ml, with a mean residence time of 207.9 h and an elimination half-life of 144.1 h (6.00 days). Plasma concentrations of cefovecin were maintained >7 µg/ml in all individuals for the entire study duration (15 days). These concentrations are lower, and the half-life slightly shorter, than the values reported for domestic cats. Cefovecin was highly protein-bound (approximately 99.9%) in cheetah plasma, which is nearly identical to domestic cats. These results indicate that cefovecin is potentially useful as a long-acting antibiotic in cheetahs.
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Acinonyx , Animais , Antibacterianos , Cefalosporinas , Injeções Intramusculares/veterináriaRESUMO
In this work, the effect of different immobilization procedures on the properties of a lipase obtained from the extremophilic microorganism Serratia sp. USBA-GBX-513, which was isolated from Paramo soils of Los Nevados National Natural Park (Colombia), is reported. Different Shepharose beads were used: octyl-(OC), octyl-glyoxyl-(OC-GLX), cyanogen bromide (BrCN)-, and Q-Sepharose. The performance of the different immobilized extremophile lipase from Serratia (ESL) was compared with that of the lipase B from Candida antarctica (CALB). In all immobilization tests, hyperactivation of ESL was observed. The highest hyperactivation (10.3) was obtained by immobilization on the OC support. Subsequently, the thermal stability at pH 5, 7, and 9 and the stability in the presence of 50% (v/v) acetonitrile, 50% dioxane, and 50% tetrahydrofuran solvents at pH 7 and 40 °C were evaluated. ESL immobilized on octyl-Sepharose was the most stable biocatalyst at 90 °C and pH 9, while the most stable preparation at pH 5 was ESL immobilized on OC-GLX-Sepharose supports. Finally, in the presence of 50% (v/v) tetrahydrofuran (THF) or dioxane at 40 °C, ESL immobilized on OC-Sepharose was the most stable biocatalyst, while the immobilized preparation of ESL on Q-Sepharose was the most stable one in 40% (v/v) acetonitrile.
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Proteínas de Bactérias/metabolismo , Enzimas Imobilizadas/metabolismo , Extremófilos/enzimologia , Lipase/metabolismo , Serratia/enzimologia , Basidiomycota/enzimologia , Biocatálise , Estabilidade Enzimática , Proteínas Fúngicas/metabolismo , Temperatura Alta , Concentração de Íons de Hidrogênio , Sefarose/análogos & derivados , Sefarose/químicaRESUMO
A 32-year-old captive female Chilean flamingo (Phoenicopterus chilensis) was diagnosed with a hypermature resorbed cataract in the right eye and a mature cataract with phacolytic uveitis in the left eye. No other systemic or neurologic physical abnormalities were detected. The patient was considered blind from bilateral cataracts, and with a reduced quality of life, surgery was indicated to remove the mature cataract in the left eye. Before surgery, the phacolytic uveitis was treated in the left eye for 1 week with topical and systemic anti-inflammatory and antibiotic medication. Unilateral phacoemulsification was performed on the left eye while under general anesthesia. The individual recovered uneventfully and regained vision in the left eye. The bird was returned to its enclosure 8 days after the surgical procedure. No abnormalities were noted in behavior or reintegration. Three weeks after the phacoemulsification was performed in the left eye, the individual presented with active uveitis, without vision loss, suspected secondary to incisional infection, which was managed with topical and systemic anti-inflammatory and antibiotic medication. At day 41 the patient was discharged with no disease conditions affecting the left eye, and the flamingo's vision was considered significantly improved compared with initial presentation. Phacoemulsification was safe and effective in removing the lens, resolving phacolytic uveitis, and restoring vision in spite of the postsurgical incisional infection. Some adaptations in the surgical approach and medical management are recommended on the basis of morphology, feeding habits, and behavior of this aquatic avian species to avoid postsurgical incisional infection and uveitis.
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Catarata , Facoemulsificação , Uveíte , Animais , Aves , Catarata/veterinária , Feminino , Facoemulsificação/efeitos adversos , Facoemulsificação/veterinária , Qualidade de Vida , Uveíte/veterináriaRESUMO
INTRODUCTION: Lung ultrasound (LUS) implementation in patients with COVID-19 can help to establish the degree of pulmonary involvement, evaluate treatment response and estimate in-hospital outcome. OBJECTIVE: To evaluate the application of a LUS protocol in patients with COVID-19 infection to predict in-hospital mortality. METHODS: The study was carried out from April 1 to August 1, 2020 in patients with COVID-19 infection admitted to the Intensive Care Unit. Lung evaluation was carried out by physicians trained in critical care ultrasonography. RESULTS: Most patients were males, median age was 56 years, and 59 % required mechanical ventilation. In-hospital mortality was 39.4 %, and in those with a LUS score ≥ 19, mortality was higher (50 %). The multiple logistic regression model showed that a LUS score ≥ 19 was significantly associated with mortality (hazard ratio = 2.55, p = 0.01). CONCLUSIONS: LUS is a safe and fast clinical tool that can be applied at bedside in patients with COVID-19 infection to establish the degree of parenchymal involvement and predict mortality.
INTRODUCCIÓN: La implementación del ultrasonido pulmonar (LUS) en los pacientes con COVID-19 puede ayudar a establecer el grado de afectación pulmonar, evaluar la respuesta al tratamiento y estimar el desenlace intrahospitalario. OBJETIVO: Evaluar la aplicación de un protocolo LUS en pacientes con infección por COVID-19 para predecir mortalidad intrahospitalaria. MÉTODOS: El estudio se realizó del 1 de abril al 1 de agosto de 2020 en pacientes con infección por COVID-19, ingresados en la Unidad de Terapia Intensiva. Se realizó evaluación pulmonar por médicos entrenados en ultrasonografía crítica. RESULTADOS: La mayoría de los pacientes fue del sexo masculino, la edad mediana fue de 56 años y 59 % requirió ventilación mecánica. La mortalidad intrahospitalaria fue de 39.4 % y en aquellos con puntuación de LUS ≥ 19, de 50 %. El modelo de regresión logística múltiple mostró que la puntuación de LUS ≥ 19 se asoció significativamente a mortalidad (cociente de riesgo = 2.55, p = 0.01). CONCLUSIONES: El LUS es una herramienta clínica segura y rápida que puede realizarse al lado de la cama de los pacientes con infección por COVID-19, para establecer el grado de afectación parenquimatosa y predecir la mortalidad.
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COVID-19/complicações , Mortalidade Hospitalar , Unidades de Terapia Intensiva , Pulmão/diagnóstico por imagem , Ultrassonografia , Idoso , COVID-19/mortalidade , Cuidados Críticos , Feminino , Hospitalização , Humanos , Masculino , Pessoa de Meia-Idade , Testes Imediatos , Respiração Artificial/estatística & dados numéricosRESUMO
The chromatin landscape has acquired deep attention from several fields ranging from cell biology to neurological and psychiatric diseases. The role that DNA modifications have on gene expression regulation has become apparent in several physiological processes, and numerous efforts have been performed to establish a relationship between DNA modifications and physiological conditions, such as cognitive performance and aging. DNA modifications are incorporated by specific sets of enzymes-the writers-and the modified DNA-interacting partners-the readers-are ultimately responsible for maintaining a functional epigenetic landscape. Therefore, understanding how these epigenetic mediators-writers and readers-are modulated in physiological aging will contribute to unraveling how aging-associated neuronal disturbances arise and contribute to the cognitive decline associated with this period of life. In this review, we focused on DNA modifications, writers and readers, highlighting that despite some methodological disparities, the evidence suggests a critical role for epigenetic mediators in the aging-associated neuronal dysfunction.
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Envelhecimento , Cognição/fisiologia , Metilação de DNA/fisiologia , Regulação da Expressão Gênica/genética , Epigênese Genética/genética , Epigênese Genética/fisiologia , Humanos , Neurônios/metabolismoRESUMO
The mid-north-eastern Caatinga is a semiarid freshwater ecoregion in North-eastern Brazil that is dominated by temporary rivers and is currently classified as one of the least ichthyologically-known ecoregions in the world. The present study aimed to provide an updated checklist of mid-north-eastern Caatinga ecoregion (MNCE) freshwater fish species and evaluate their taxonomic identity using morphology, DNA barcoding and multiple species delimitation approaches. After reviewing published studies and ichthyological collections, 119 species were identified. Among these were 94 putatively valid native and 14 non-native species, five undescribed native species, four new records for the MNCE, 11 potential cases of misidentification and 14 species listed as inquirenda. Additionally, 252 individuals from 49 species were barcoded, revealing three potential taxonomic synonyms. The combined molecular approaches estimated a total of 91 native species, although a finalized species list for the MNCE awaits additional taxonomic revisions and field surveys. This study provides the most up-to-date species checklist for the MNCE and a molecular reference database for identifying MNCE fishes with DNA barcodes. Results highlight the need to integrate traditional taxonomy with molecular approaches to correctly identify species, especially in taxonomically problematic ecoregions such as the MNCE.
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Biodiversidade , Lista de Checagem , Peixes/classificação , Animais , Brasil , DNA , Código de Barras de DNA Taxonômico , Água Doce , RiosRESUMO
Reptiles are one of the most diverse groups of vertebrates, providing an integrated system for comparative studies on metabolic, animal physiology, and developmental biology. However, the molecular data available are limited and only recently have started to call attention in the "omics" sciences. Mabuya sp. is a viviparous placentrotrophic skink with particular reproductive features, including microlecithal eggs, early luteolysis, prolonged gestation, and development of a highly specialized placenta. This placenta is responsible for respiratory exchange and the transference of all nutrients necessary for embryonic development. Our aim was to identify differentially expressed proteins in the ovary and placenta of Mabuya sp. during early, mid, and late gestation; their possible metabolic pathways; and biological processes. We carried out a comparative proteomic analysis during gestation in both tissues by sodium dodecyl sulfate polyacrylamide gel electrophoresis, two-dimensional gel electrophoresis, and matrix-assisted laser desorption/ionization. Differential protein expression in both tissues (Student's t-test P < 0.05) was related to several processes such as cell structure, cell movement, and energy. Proteins found in ovary are mainly associated with follicular development and its regulation. In the placenta, particularly during mid and late gestation, protein expression is involved in nutrient metabolism, transport, protein synthesis, and embryonic development. This work provides new insights about the proteins expressed and their physiological mechanisms in Mabuya sp. placenta and ovary during gestation.
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Regulação da Expressão Gênica/fisiologia , Lagartos/fisiologia , Ovário/metabolismo , Proteômica , Transcriptoma , Viviparidade não Mamífera/fisiologia , Animais , FemininoRESUMO
Recent work has shown that the behaviour of marine organisms can be affected by elevated PCO2 , although little is known about the effect of multiple stressors. We therefore investigated the effect of elevated PCO2 and temperature on locomotion and behaviour during prey searching in the marine gastropod Concholepas concholepas, a predator characteristic of the southeastern Pacific coast. Movement duration, decision time, route finding and lateralization were measured using a T-maze tank with a prey positioned behind a barrier. Four treatments, representing present day and near-future scenarios of ocean acidification and warming were used in rearing the individuals for 6â months. Regardless of the treatment, no significant differences were found in relative and absolute lateralization before and after exposure for 6 months. However, relative lateralization was not repeatable for animals tested after 6â months at elevated PCO2 at both experimental temperatures, whereas it was repeatable in individuals kept at the present day level of PCO2 We suggest that these effects may be related to a behavioural malfunction caused by elevated PCO2 Movement duration, decision time and route finding were not repeatable. However, movement duration and decision time increased and route finding decreased in elevated PCO2 (at 15°C), suggesting that elevated PCO2 has negative effects on the locomotor and sensory performance of C. concholepas in the presence of a prey odour, thereby decreasing their ability to forage efficiently.
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Dióxido de Carbono/metabolismo , Gastrópodes/fisiologia , Aquecimento Global , Animais , Comportamento Apetitivo , Organismos Aquáticos/fisiologia , Dióxido de Carbono/análise , Temperatura Alta , Locomoção , Orientação , Comportamento Predatório , Água do Mar/análiseRESUMO
Phenotypic plasticity is expected to play a major adaptive role in the response of species to ocean acidification (OA), by providing broader tolerances to changes in pCO2 conditions. However, tolerances and sensitivities to future OA may differ among populations within a species because of their particular environmental context and genetic backgrounds. Here, using the climatic variability hypothesis (CVH), we explored this conceptual framework in populations of the sea urchin Loxechinus albus across natural fluctuating pCO2/pH environments. Although elevated pCO2 affected the morphology, physiology, development and survival of sea urchin larvae, the magnitude of these effects differed among populations. These differences were consistent with the predictions of the CVH showing greater tolerance to OA in populations experiencing greater local variation in seawater pCO2/pH. Considering geographical differences in plasticity, tolerances and sensitivities to increased pCO2 will provide more accurate predictions for species responses to future OA.