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1.
Front Psychiatry ; 15: 1407586, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39290314

RESUMEN

This paper investigates the lived experience of alienation as a form of mental strife or pathology as it is connected to the digitalization of modern life. To do so, I deploy the concept of affordances from ecological psychology, phenomenology, and embodied cognition. I propose an affordance-based model for understanding digitalized alienation. First, I argue that the lived sense of alienation is best understood as a fracturing of the affordance space, where possibilities for action are lived as disconnected from one another and therefore from one's personal development and search for meaning. Using this model, I show how the process of digitalization can lead to a lived sense of alienation for modern subjects. On this model, digitalization is alienating insofar as it fractures the affordance space into disconnected fields that invite determinate, separate, and repeatable tasks-swiping, clicking, scrolling, etc.-rather than offering opportunities for the development of new cognitive and bodily skills that are mutually informing and enriching across different affordance fields.

2.
Front Med (Lausanne) ; 11: 1396459, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39257886

RESUMEN

The Cancer of Unknown Primary (CUP) syndrome is characterized by identifiable metastases while the primary tumor remains hidden. In recent years, various data-driven approaches have been suggested to predict the location of the primary tumor (LOP) in CUP patients promising improved diagnosis and outcome. These LOP prediction approaches use high-dimensional input data like images or genetic data. However, leveraging such data is challenging, resource-intensive and therefore a potential translational barrier. Instead of using high-dimensional data, we analyzed the LOP prediction performance of low-dimensional data from routine medical care. With our findings, we show that such low-dimensional routine clinical information suffices as input data for tree-based LOP prediction models. The best model reached a mean Accuracy of 94% and a mean Matthews correlation coefficient (MCC) score of 0.92 in 10-fold nested cross-validation (NCV) when distinguishing four types of cancer. When considering eight types of cancer, this model achieved a mean Accuracy of 85% and a mean MCC score of 0.81. This is comparable to the performance achieved by approaches using high-dimensional input data. Additionally, the distribution pattern of metastases appears to be important information in predicting the LOP.

3.
Eye (Lond) ; 2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39198702

RESUMEN

INTRODUCTION: Selective laser trabeculoplasty has been carried out at Lancashire Teaching Hospitals over the past seven years. This work aimed to review the use of SLT in this Trust. The primary objectives were to establish the efficacy of SLT in reducing intraocular pressure, to analyse how prior treatment with different topical medications can influence SLT outcomes and to analyse the outcomes in revisionary patients. METHOD: We conducted a retrospective review of 288 eyes, with a known history of glaucoma or ocular hypertension and who underwent initial SLT laser treatment between October 2018 and January 2020. SLT was performed on known glaucoma and treatment naïve patients where IOP control was deemed sub-optimal. All patient data was fully anonymised. RESULTS: We found that SLT was effective in lowering IOP. Around two-thirds of the eyes (181/280, 65%) achieved a reduction in IOP of 10% or more. Just under half (127/280, 45%) achieved a reduction of 20% or more. For a pre-SLT IOP of 14.6 mmHg, we found that no mean change in IOP is expected, and for each 1 mmHg by which the pre-SLT IOP exceeds this threshold, the mean reduction in IOP is expected to be 0.61 mmHg. We also found that combination therapies of PGA plus aqueous suppressants gave better outcomes compared with PGA alone. We found that revisionary SLT compared favourably with the first treatment, although first-time outcomes were not a good predictor of success with revisionary SLT. CONCLUSION: Primary and revisionary SLT has been shown to be effective across the cohort of patients in this study.

4.
J Anim Ecol ; 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-39049456

RESUMEN

Supplemental feeding can increase the overall health of animals but also can have variable effects on how animals defend themselves against parasites. However, the spatiotemporal effects of food supplementation on host-parasite interactions remain poorly understood, likely because large-scale, coordinated efforts to investigate them are difficult. Here, we introduce the Nest Parasite Community Science Project, which is a community-based science project that coordinates studies with bird nest box 'stewards' from the public and scientific community. This project was established to understand broad ecological patterns between hosts and their parasites. The goal of this study was to determine the effect of food supplementation on eastern bluebirds (Sialia sialis) and their nest parasite community across the geographic range of the bluebirds from 2018 to 2021. We received 674 nests from 69 stewards in 26 states in the eastern United States. Nest box stewards reported whether or not they provided mealworms or suet near nesting bluebirds, then they followed the nesting success of the birds (number of eggs laid and hatched, proportion that hatched, number and proportion of nestlings that successfully fledged). We then identified and quantified parasites in the nests. Overall, we found that food supplementation increased fledging success. The most common nest parasite taxon was the parasitic blow fly (Protocalliphora sialia), but a few nests contained fleas (Ceratophyllus idius, C. gallinae and Orchopeas leucopus) and mites (Dermanyssus spp. and Ornithonyssus spp.). Blow flies were primarily found at northern latitudes, where food supplementation affected blow fly prevalence. However, the direction of this effect varied substantially in direction and magnitude across years. More stewards fed bluebirds at southern latitudes than at northern latitudes, which contradicts the findings of other community-based science projects. Overall, food supplementation of birds was associated with increased host fitness but did not appear to play a consistent role in defence against these parasites across all years. Our study demonstrates the importance of coordinated studies across years and locations to understand the effects of environmental heterogeneity, including human-based food supplementation, on host-parasite dynamics.

5.
Brain Behav Immun ; 121: 56-69, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39043341

RESUMEN

Alzheimer's Disease (AD) is a neurodegenerative disease characterized by profound memory impairments, synaptic loss, neuroinflammation, and hallmark pathological markers. High-fat diet (HFD) consumption increases the risk of developing AD even after controlling for metabolic syndrome, pointing to a role of the diet itself in increasing risk. In AD, the complement system, an arm of the immune system which normally tags redundant or damaged synapses for pruning, becomes pathologically overactivated leading to tagging of healthy synapses. While the unhealthy diet to AD link is strong, the underlying mechanisms are not well understood in part due to confounding variables associated with long-term HFD which can independently influence the brain. Therefore, we experimented with a short-term diet regimen to isolate the diet's impact on brain function without causing obesity. This project investigated the effect of short-term HFD on 1) memory, 2) neuroinflammation including complement, 3) AD pathology markers, 4) synaptic markers, and 5) in vitro microglial synaptic phagocytosis in the 3xTg-AD mouse model. Following the consumption of either standard chow or HFD, 3xTg-AD and non-Tg mice were tested for memory impairments. In a separate cohort of mice, levels of hippocampal inflammatory markers, complement proteins, AD pathology markers, and synaptic markers were measured. For the last set of experiments, BV2 microglial phagocytosis of synapses was evaluated. Synaptoneurosomes isolated from the hippocampus of 3xTg-AD mice fed chow or HFD were incubated with equal numbers of BV2 microglia. The number of BV2 microglia that phagocytosed synaptoneurosomes was tracked over time with a live-cell imaging assay. Finally, we incubated BV2 microglia with a complement receptor inhibitor (NIF) and repeated the assay. Behavioral analysis showed 3xTg-AD mice had significantly impaired long-term contextual and cued fear memory compared to non-Tg mice that was further impaired by HFD. HFD significantly increased inflammatory markers and complement expression while decreasing synaptic marker expression only in 3xTg-AD mice, without altering AD pathology markers. Synaptoneurosomes from HFD-fed 3xTg-AD mice were phagocytosed at a significantly higher rate than those from chow-fed mice, suggesting the synapses were altered by HFD. The complement receptor inhibitor blocked this effect in a dose-dependent manner, demonstrating the HFD-mediated increase in phagocytosis was complement dependent. This study indicates HFD consumption increases neuroinflammation and over-activates the complement cascade in 3xTg-AD mice, resulting in poorer memory. The in vitro data point to complement as a potential mechanistic culprit and therapeutic target underlying HFD's influence in increasing cognitive vulnerability to AD.


Asunto(s)
Enfermedad de Alzheimer , Dieta Alta en Grasa , Modelos Animales de Enfermedad , Ratones Transgénicos , Microglía , Sinapsis , Animales , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/inmunología , Dieta Alta en Grasa/efectos adversos , Ratones , Sinapsis/metabolismo , Microglía/metabolismo , Trastornos de la Memoria/metabolismo , Trastornos de la Memoria/inmunología , Masculino , Proteínas del Sistema Complemento/metabolismo , Memoria/fisiología , Enfermedades Neuroinflamatorias/metabolismo , Enfermedades Neuroinflamatorias/inmunología , Ratones Endogámicos C57BL , Encéfalo/metabolismo , Encéfalo/inmunología , Hipocampo/metabolismo , Neuroinmunomodulación/fisiología
6.
Plast Reconstr Surg Glob Open ; 12(6): e5865, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38841531

RESUMEN

Background: Free flap monitoring is more difficult in patients with dark skin because ischemia and congestion can be masked by pigmentation. For this reason, adjunct methods such as cutaneous near-infrared spectroscopy are of elevated importance in patients with highly pigmented skin. The purpose of this experiment is to determine if ViOpitx T.Ox performance is affected by cutaneous pigmentation. Methods: Swine with naturally occurring areas of nonpigmented and pigmented skin were used. Pigmentation of each animal was assessed using spectrophotometry and histopathology. During normoxemia, tissue oxygenation (StO2) measurements were taken of nonpigmented and pigmented skin using the T.Ox device. A bicolor pedicled rectus abdominis myocutaneous flap was raised, and T.Ox probe was adhered to adjacent areas of opposite coloration on the same flap. StO2 was measured continuously during reversible episodes of flap ischemia and congestion (n = 4 swine, n = 6 flaps). Results: There was not a significant difference between baseline StO2 values of nonpigmented (49% ± 7.9%) and pigmented skin (47% ± 6.2%). The absolute change in StO2 was significantly larger during both ischemia (6%) and congestion (16%) in nonpigmented skin compared with adjacent pigmented skin. Conclusions: T.Ox detects flap ischemia and congestion in both highly pigmented and nonpigmented skin. However, surgeons need to be aware that StO2 changes related to complete flap ischemia or congestion may be much more subtle than what is seen in nonpigmented skin. This study establishes a novel internally controlled porcine model that isolates the impact of skin pigmentation when assessing cutaneous devices measuring tissue oxygenation.

7.
Biotechnol Prog ; : e3469, 2024 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-38613439

RESUMEN

Reliable monitoring of mammalian cells in bioreactors is essential to biopharmaceutical production. Trypan blue exclusion is a method of determining cell density and viability that has been used for over one hundred years to monitor cells in culture and is the current standard method in biomanufacturing. This method has many disadvantages however and there is a growing demand for more detailed and in-line measurements of cell growth in bioreactors. This article assesses a novel dynamic imaging system for single cell analysis. This data shows that comparable total cell density, viable cell density and percentage viability data shown here, generated by the imaging system, aligned well with conventional trypan blue counting methods for an industrially relevant Chinese Hamster Ovary (CHO) cell line. Furthermore, detailed statistical analysis shows that the classification system used by the PharmaFlow system can reveal trends of interest in monitoring the health of mammalian cells over a 6-day bioreactor culture. The system is also capable of sampling at-line, removing the necessity for taking samples off-line and enabling real time monitoring of cells in a bioreactor culture.

9.
Biotechnol Prog ; 40(4): e3450, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38476025

RESUMEN

Foam is generated in mammalian cell cultures by excessive agitation or gas sparging. This occurs particularly in cultures that generate recombinant proteins at high cell concentrations. Three antifoam agents were tested for their compatibility with antibody-producing Chinese hamster ovary (CHO) cells. One agent (antifoam 204) was completely inhibitory to growth at a concentration of 10 ppm, one agent (antifoam C) showed partial inhibition and a third (antifoam SE-15) showed no inhibition at this concentration. A novel foam image analyzer (LabCam) was used to evaluate two antifoams (C and SE-15) for their ability to dissipate foam generated in cell culture media by enhanced agitation. The presence of antifoam in the media reduced significantly the foam layer that was generated and this was shown to be rapidly dissipated in the presence of 10 ppm SE-15. The antifoams were also tested for foam dissipation in cultures of CHO cells at >106 cells/mL. Supplementation of the cultures with SE-15 resulted in dissipation of foam generated by excessive gas sparging within 2 min. Under equivalent conditions 75% of foam dissipated in the presence of antifoam C, within 2 min but there was a residual foam layer up to 25 min. This study showed the value of an optical monitoring system (LabCam) for measuring foam generation and dissipation in a bioreactor to assess the efficiency of antifoam agents to reduce foam in a bioreactor. This has the potential for use as a control system that could be designed for continuous monitoring and foam control in a mammalian cell bioprocess.


Asunto(s)
Técnicas de Cultivo de Célula , Cricetulus , Células CHO , Animales , Técnicas de Cultivo de Célula/métodos , Cricetinae , Medios de Cultivo/química , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/biosíntesis
10.
Bone Jt Open ; 5(2): 132-138, 2024 02 13.
Artículo en Inglés | MEDLINE | ID: mdl-38346449

RESUMEN

Aims: The primary aim of this study was to report the radiological outcomes of patients with a dorsally displaced distal radius fracture who were randomized to a moulded cast or surgical fixation with wires following manipulation and closed reduction of their fracture. The secondary aim was to correlate radiological outcomes with patient-reported outcome measures (PROMs) in the year following injury. Methods: Participants were recruited as part of DRAFFT2, a UK multicentre clinical trial. Participants were aged 16 years or over with a dorsally displaced distal radius fracture, and were eligible for the trial if they needed a manipulation of their fracture, as recommended by their treating surgeon. Participants were randomly allocated on a 1:1 ratio to moulded cast or Kirschner wires after manipulation of the fracture in the operating theatre. Standard posteroanterior and lateral radiographs were performed in the radiology department of participating centres at the time of the patient's initial assessment in the emergency department and six weeks postoperatively. Intraoperative fluoroscopic images taken at the time of fracture reduction were also assessed. Results: Patients treated with surgical fixation with wires had less dorsal angulation of the radius versus those treated in a moulded cast at six weeks after manipulation of the fracture; the mean difference of -4.13° was statistically significant (95% confidence interval 5.82 to -2.45). There was no evidence of a difference in radial shortening. However, there was no correlation between these radiological measurements and PROMs at any timepoint in the 12 months post-injury. Conclusion: For patients with a dorsally displaced distal radius fracture treated with a closed manipulation, surgical fixation with wires leads to less dorsal angulation on radiographs at six weeks compared with patients treated in a moulded plaster cast alone. However, the difference in dorsal angulation was small and did not correlate with patient-reported pain and function.

12.
Glycobiology ; 34(1)2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-37774344

RESUMEN

Adeno-associated virus (AAV) vector has become the leading platform for gene delivery. Each serotype exhibits a different tissue tropism, immunogenicity, and in vivo transduction performance. Therefore, selecting the most suitable AAV serotype is critical for efficient gene delivery to target cells or tissues. Genome divergence among different serotypes is due mainly to the hypervariable regions of the AAV capsid proteins. However, the heterogeneity of capsid glycosylation is largely unexplored. In the present study, the N-glycosylation profiles of capsid proteins of AAV serotypes 1 to 9 have been systemically characterized and compared using a previously developed high-throughput and high-sensitivity N-glycan profiling platform. The results showed that all 9 investigated AAV serotypes were glycosylated, with comparable profiles. The most conspicuous feature was the high abundance mannosylated N-glycans, including FM3, M5, M6, M7, M8, and M9, that dominated the chromatograms within a range of 74 to 83%. Another feature was the relatively lower abundance of fucosylated and sialylated N-glycan structures, in the range of 23%-40% and 10%-17%, respectively. However, the exact N-glycan composition differed. These differences may be utilized to identify potential structural relationships between the 9 AAV serotypes. The current research lays the foundation for gaining better understanding of the importance of N-glycans on the AAV capsid surface that may play a significant role in tissue tropism, interaction with cell surface receptors, cellular uptake, and intracellular processing.


Asunto(s)
Proteínas de la Cápside , Dependovirus , Proteínas de la Cápside/química , Dependovirus/genética , Dependovirus/metabolismo , Serogrupo , Glicómica , Vectores Genéticos , Polisacáridos/metabolismo
14.
Brain Behav Immun ; 116: 385-401, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38145855

RESUMEN

Post-operative cognitive dysfunction (POCD) is an abrupt decline in neurocognitive function arising shortly after surgery and persisting for weeks to months, increasing the risk of dementia diagnosis. Advanced age, obesity, and comorbidities linked to high-fat diet (HFD) consumption such as diabetes and hypertension have been identified as risk factors for POCD, although underlying mechanisms remain unclear. We have previously shown that surgery alone, or 3-days of HFD can each evoke sufficient neuroinflammation to cause memory deficits in aged, but not young rats. The aim of the present study was to determine if HFD consumption before surgery would potentiate and prolong the subsequent neuroinflammatory response and memory deficits, and if so, to determine the extent to which these effects depend on activation of the innate immune receptor TLR4, which both insults are known to stimulate. Young-adult (3mo) & aged (24mo) male F344xBN F1 rats were fed standard chow or HFD for 3-days immediately before sham surgery or laparotomy. In aged rats, the combination of HFD and surgery caused persistent deficits in contextual memory and cued-fear memory, though it was determined that HFD alone was sufficient to cause the long-lasting cued-fear memory deficits. In young adult rats, HFD + surgery caused only cued-fear memory deficits. Elevated proinflammatory gene expression in the hippocampus of both young and aged rats that received HFD + surgery persisted for at least 3-weeks after surgery. In a separate experiment, rats were administered the TLR4-specific antagonist, LPS-RS, immediately before HFD onset, which ameliorated the HFD + surgery-associated neuroinflammation and memory deficits. Similarly, dietary DHA supplementation for 4 weeks prior to HFD onset blunted the neuroinflammatory response to surgery and prevented development of persistent memory deficits. These results suggest that HFD 1) increases risk of persistent POCD-associated memory impairments following surgery in male rats in 2) a TLR4-dependent manner, which 3) can be targeted by DHA supplementation to mitigate development of persistent POCD.


Asunto(s)
Disfunción Cognitiva , Complicaciones Cognitivas Postoperatorias , Ratas , Masculino , Animales , Receptor Toll-Like 4/metabolismo , Dieta Alta en Grasa/efectos adversos , Enfermedades Neuroinflamatorias , Trastornos de la Memoria/metabolismo , Hipocampo/metabolismo , Complicaciones Cognitivas Postoperatorias/metabolismo , Suplementos Dietéticos , Disfunción Cognitiva/metabolismo
15.
Anal Biochem ; 680: 115311, 2023 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-37666384

RESUMEN

Adeno-associated virus (AAV) is the leading platform for in vivo gene therapy to treat numerous genetic diseases. Comprehensive analysis of the AAV particles is essential to ensure desired safety and efficacy. An array of techniques is required to evaluate their critical quality attributes. However, many of these techniques are expensive, time-consuming, labour-intensive, and varying in accuracy. Size exclusion chromatography coupled with fluorescence and triple-wavelength ultraviolet detection (SEC-FLD-TWUV) and incorporating an aromatic amino acid of tryptophan as an internal standard offers a simple, rapid, and reliable approach for simultaneous multi-attribute analysis of AAVs. In the current study, we demonstrate its capability for AAV characterization and quantification, that includes capsid concentration, empty to full capsid ratio, vector genome concentration, and the presence of aggregates or fragments. All were performed in 20-min chromatographic runs with minimal sample handling. Data analysis involves the assessment of intrinsic fluorescence and UV absorbance of samples at three wavelengths that can be utilised to determine the content of the capsid protein and genome copy number. The separation efficiency using SEC columns with different pore sizes, and elution buffers of varying compositions, ionic strength, and pH values was also evaluated. This SEC-FLD-TWUV method may serve as a powerful yet cost-effective tool for responsive quality evaluation of AAVs. This may enhance performance, robustness, and safety of bioprocessing for AAV vectors to be used in gene therapy.


Asunto(s)
Proteínas de la Cápside , Dependovirus , Dependovirus/genética , Cromatografía en Gel , Proteínas de la Cápside/genética , Terapia Genética , Triptófano
16.
Front Cell Neurosci ; 17: 1227241, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37636589

RESUMEN

The consumption of diets high in saturated fatty acids and/or refined carbohydrates are associated with neuroinflammation, cognitive dysfunction, and neurodegenerative disease. In contrast, diets high in polyunsaturated fatty acids are associated with anti-inflammatory and neuroprotective effects. We have previously shown that high fat diet (HFD) consumption increases saturated fatty acids and decreases polyunsaturated fatty acids in the hippocampus. We have further shown that HFD elicits exaggerated neuroinflammation and reduced synaptic elements, and results in robust memory deficits in aged rats. Here, we examined the impact of palmitate, an abundant dietary saturated fat, on a variety of cellular responses in BV2 microglia and HippoE-14 neurons, and the extent to which the omega-3 fatty acid, docosahexaenoic acid (DHA), would buffer against these responses. Our data demonstrate that DHA pretreatment prevents or partially attenuates palmitate-induced alterations in proinflammatory, endoplasmic reticulum stress, and mitochondrial damage-associated gene expression in both cell types. Furthermore, we show that synaptoneurosomes isolated from aged, HFD-fed mice are engulfed by BV2 microglia at a faster rate than synaptoneurosomes isolated from aged, chow-fed mice, suggesting HFD alters signaling at synapses to hasten their engulfment by microglia. Consistent with this notion, we found modest increases in complement proteins and a decrease in CD47 protein expression on synaptoneurosomes isolated from the hippocampus of aged, HFD-fed mice. Interestingly, palmitate reduced BV2 microglial phagocytosis, but only of synaptoneurosomes isolated from chow-fed mice, an effect that was prevented by DHA pretreatment. Lastly, we measured the impact of palmitate and DHA on mitochondrial function in both microglial and neuronal cell models using the Seahorse XFe96 Analyzer. These data indicate that DHA pretreatment does not mitigate palmitate-induced reductions in mitochondrial respiration in BV2 microglia and HippoE-14 neurons, suggesting DHA may be acting downstream of mitochondrial function to exert its protective effects. Together, this study provides evidence that DHA can ameliorate the negative impact of palmitate on a variety of cellular functions in microglia- and neuron-like cells.

17.
Physiol Biochem Zool ; 96(4): 294-303, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37418605

RESUMEN

AbstractAntioxidants have important physiological roles in limiting the amount of oxidative damage that an organism experiences. One putative antioxidant is biliverdin, a pigment that is most commonly associated with the blue or green colors of avian eggshells. However, despite claims that biliverdin functions as an antioxidant, neither the typical physiological concentrations of biliverdin in most species nor the ability of biliverdin to oppose oxidative damage at these concentrations has been examined. Therefore, we quantified biliverdin in the plasma of six bird species and found that they circulated levels of biliverdin between 0.02 and 0.5 µM. We then used a pool of plasma from northern bobwhite quail (Colinus virginianus) and spiked it with one of seven different concentrations of biliverdin, creating plasma-based solutions ranging from 0.09 to 231 µM biliverdin. We then compared each solution's ability to oppose oxidative damage in response to hydrogen peroxide relative to a control addition of water. We found that hydrogen peroxide consistently induced moderate amounts of oxidative damage (quantified as reactive oxygen metabolites) but that no concentration of biliverdin ameliorated this damage. However, biliverdin and hydrogen peroxide interacted, as the amount of biliverdin in hydrogen peroxide-treated samples was reduced to approximately zero, unless the initial concentration was over 100 µM biliverdin. These preliminary findings based on in vitro work indicate that while biliverdin may have important links to metabolism and immune function, at physiologically relevant concentrations it does not detectably oppose hydrogen peroxide-induced oxidative damage in plasma.


Asunto(s)
Antioxidantes , Biliverdina , Animales , Biliverdina/metabolismo , Antioxidantes/metabolismo , Peróxido de Hidrógeno , Estrés Oxidativo
19.
J Comp Physiol B ; 193(3): 315-328, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36995413

RESUMEN

Changes in the physiological health of species are an essential indicator of changing conditions and environmental challenges. Reponses to environmental challenges can often induce stress, influence physiology, and change metabolism in organisms. Here we tested blood chemistry parameters indicative of stress and metabolic activity using an i-STAT point-of-care blood analyzer in seven populations of free-ranging rock iguanas exposed to varying levels of tourism and supplemental feeding. We found significant differences in blood chemistry (glucose, oxygen, carbon dioxide, hematocrit, hemoglobin, calcium, potassium, and biliverdin levels) among populations exposed to varying levels of tourism, and some variation between sexes and reproductive states. However, different variables are not directly related to one another, suggesting that the causal physiological pathways driving tourism-induced differences are influenced by mechanisms that are not detected by common analyses of blood chemistry. Future work should investigate upstream regulators of these factors affected by tourism. Regardless, these blood metrics are known to be both stress sensitive and related to metabolic activity, suggesting that exposure to tourism and associated supplemental feeding by tourists are generally driven by stress-related changes in blood chemistry, biliverdin, and metabolism.


Asunto(s)
Iguanas , Lagartos , Animales , Turismo , Biliverdina , Reproducción
20.
Brain Res Bull ; 195: 145-156, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36870621

RESUMEN

Global populations are increasingly consuming diets high in saturated fats and refined carbohydrates, and such diets have been well-associated with heightened inflammation and neurological dysfunction. Notably, older individuals are particularly vulnerable to the impact of unhealthy diet on cognition, even after a single meal, and pre-clinical rodent studies have demonstrated that short-term consumption of high-fat diet (HFD) induces marked increases in neuroinflammation and cognitive impairment. Unfortunately though, to date, most studies on the topic of nutrition and cognition, especially in aging, have been performed only in male rodents. This is especially concerning given that older females are more vulnerable to develop certain memory deficits and/or severe memory-related pathologies than males. Thus, the aim of the present study was to determine the extent to which short-term HFD consumption impacts memory function and neuroinflammation in female rats. Young adult (3 months) and aged (20-22 months) female rats were fed HFD for 3 days. Using contextual fear conditioning, we found that HFD had no effect on long-term contextual memory (hippocampus-dependent) at either age, but impaired long-term auditory-cued memory (amygdala-dependent) regardless of age. Gene expression of Il-1ß was markedly dysregulated in the amygdala, but not hippocampus, of both young and aged rats after 3 days of HFD. Interestingly, modulation of IL-1 signaling via central administration of the IL-1 receptor antagonist (which we have previously demonstrated to be protective in males) had no impact on memory function following the HFD in females. Investigation of the memory-associated gene Pacap and its receptor Pac1r revealed differential effects of HFD on their expression in the hippocampus and amygdala. Specifically, HFD induced increased expression of Pacap and Pac1r in the hippocampus, whereas decreased Pacap was observed in the amygdala. Collectively, these data suggest that both young adult and aged female rats are vulnerable to amygdala-dependent (but not hippocampus-dependent) memory impairments following short-term HFD consumption, and identify potential mechanisms related to IL-1ß and PACAP signaling in these differential effects. Notably, these findings are strikingly different than those previously reported in male rats using the same diet regimen and behavioral paradigms, and highlight the importance of examining potential sex differences in the context of neuroimmune-associated cognitive dysfunction.


Asunto(s)
Dieta Alta en Grasa , Enfermedades Neuroinflamatorias , Ratas , Animales , Femenino , Masculino , Dieta Alta en Grasa/efectos adversos , Polipéptido Hipofisario Activador de la Adenilato-Ciclasa/metabolismo , Trastornos de la Memoria/etiología , Trastornos de la Memoria/metabolismo , Amígdala del Cerebelo/metabolismo
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