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1.
Mol Biol Rep ; 51(1): 278, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38319482

RESUMO

BACKGROUND: Stress is one of the prevalent factors influencing cognition. Several studies examined the effect of mild or chronic stress on cognition. However, most of these studies are limited to a few behavioral tests or the expression of selected RNA/proteins markers in a selected brain region. METHODS: This study examined the effect of restraint stress on learning, memory, cognition, and expression of transcripts in key learning centers. Male mice were divided into three groups (n = 6/group)-control group, stress group (adult stressed group; S), and F1 group (parental stressed group). Stress group mice were subjected to physical restraint stress for 2 h before light offset for 2 weeks. The F1 group comprised adult male mice born of stressed parents. All animals were subjected to different tests and were sacrificed at the end. Transcription levels of Brain-Derived Neurotrophic Factor (Bdnf), Tyrosine kinase (TrkB), Growth Associated Protein 43 (Gap-43), Neurogranin (Ng), cAMP Response Element-Binding Protein (Creb), Glycogen synthase kinase-3ß (Gsk3ß), Interleukine-1 (IL-1) and Tumour necrosis factor-α (Tnf-α) were studied. RESULTS: Results show that both adult and parental stress negatively affect learning, memory and cognition, as reflected by taking longer time to achieve the task or showing reduced exploratory behavior. Expression of Bdnf, TrkB, Gsk3ß and Ng was downregulated, while IL-1 and Tnf-α were upregulated in the brain's cortex, thalamus, and hippocampus region of stressed mice. These effects seem to be relatively less severe in the offspring of stressed parents. CONCLUSIONS: The findings suggest that physical restraint stress can alter learning, memory, cognition, and expression of transcripts in key learning centers of brain.


Assuntos
Fator Neurotrófico Derivado do Encéfalo , Restrição Física , Masculino , Animais , Camundongos , Fator Neurotrófico Derivado do Encéfalo/genética , Glicogênio Sintase Quinase 3 beta , Fator de Necrose Tumoral alfa , Cognição , Encéfalo , Interleucina-1 , Proteínas Tirosina Quinases
2.
Cochrane Database Syst Rev ; 1: CD012265, 2024 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-38258877

RESUMO

BACKGROUND: The intestinal microflora has an essential role in providing a barrier against colonisation of pathogens, facilitating important metabolic functions, stimulating the development of the immune system, and maintaining intestinal motility. Probiotics are live microorganisms that can be administered to supplement the gut flora. Neonates who have undergone gastrointestinal surgery are particularly susceptible to infectious complications in the postoperative period. This may be partly due to a disruption of the integrity of the gut and its intestinal microflora. There may be a role for probiotics in reducing the incidence of sepsis and improving intestinal motility, thus reducing morbidity and mortality and improving enteral feeding in neonates in the postoperative period. OBJECTIVES: To evaluate the efficacy and safety of administering probiotics after gastrointestinal surgery for the postoperative management of neonates born from 35 weeks of gestation. SEARCH METHODS: We searched CENTRAL, MEDLINE, Embase, and trial registries in August 2023. We checked reference lists of included studies and relevant systematic reviews for additional studies. SELECTION CRITERIA: We included randomised controlled trials (RCTs) that investigated the postoperative administration of oral probiotics versus placebo or no treatment in neonates born from 35 weeks of gestation who had one or more gastrointestinal surgical procedures. We applied no restrictions regarding the type or dosage of probiotics or the duration of treatment. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods, and we used GRADE to assess the certainty of evidence. MAIN RESULTS: We identified one RCT that recruited 61 neonates with a gestational age of 35 weeks or more. All infants were admitted to a neonatal intensive care unit and had surgery for gastrointestinal pathologies. There may be little or no difference in proven sepsis (positive bacterial culture, local or systemic) between infants who receive probiotics compared with those who receive placebo (odds ratio (OR) 0.64, 95% confidence interval (CI) 0.16 to 2.55; 61 infants; low-certainty evidence). Probiotics compared to placebo may have little or no effect on time to full enteral feeds (mean difference (MD) 0.63 days, 95% CI -4.02 to 5.28; 61 infants; low-certainty evidence). There were no reported deaths prior to discharge from hospital in either study arm. Two weeks after supplementation, the infants who received probiotics had a substantially higher relative abundance of non-pathogenic intestinal microflora (Bifidobacteriaceae) than those who received placebo (MD 38.22, 95% CI 28.40 to 48.04; 39 infants; low-certainty evidence). AUTHORS' CONCLUSIONS: This review provides low-certainty evidence from one small RCT that probiotics compared to placebo have little or no effect on the risk of proven sepsis (positive bacterial culture, local or systemic) or time to full-enteral feeds in neonates who have undergone gastrointestinal surgery. Probiotics may substantially increase the abundance of beneficial bacterial in the intestine of these neonates, but the clinical implications of this finding are unknown. There is a need for adequately powered RCTs to assess the role of probiotics in this population. We identified two ongoing studies. As neither reported the gestational age of prospective study participants, we are unsure if they will be eligible for inclusion in this review.


Assuntos
Procedimentos Cirúrgicos do Sistema Digestório , Probióticos , Sepse , Lactente , Recém-Nascido , Humanos , Probióticos/uso terapêutico , Suplementos Nutricionais , Procedimentos Cirúrgicos do Sistema Digestório/efeitos adversos , Nutrição Enteral , Sepse/prevenção & controle
3.
Cochrane Database Syst Rev ; 1: CD008771, 2024 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-38275196

RESUMO

BACKGROUND: Observational studies in preterm newborns suggest that delay in administering amino acids (AA) could result in a protein catabolic state and impact on growth and development. OBJECTIVES: The objective of this review was to compare the efficacy and safety of early versus late administration of intravenous AA in neonates born at < 37 weeks of gestation. SEARCH METHODS: We searched CENTRAL, MEDLINE, Embase, and trial registries in March 2023. We checked the reference lists of included studies and studies/systematic reviews where subject matter related to the intervention or population examined in this review. SELECTION CRITERIA: We included randomised controlled trials (RCTs) comparing early administration of AA with late administration in premature newborn infants. We defined early administration of AA solution as the administration of AA in isolation or with total parenteral nutrition within the first 24 hours of birth, and late administration as the administration of AA in isolation or with total parenteral nutrition after the first 24 hours of birth. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methodological procedures. We used the GRADE approach to assess the certainty of the evidence. MAIN RESULTS: Nine studies (383 participants) were eligible for inclusion in the review. All study participants were born at < 37 weeks of gestation and were inpatients in neonatal intensive care units. No studies reported growth during the first months of life as assessed by difference in weight. Early administration of AA may have little or no effect on growth in the first month of life as measured by length (mean difference (MD) 0.00, 95% confidence interval (CI) -0.41 to 0.41; 1 study; 21 participants; low-certainty evidence) and head circumference (MD 0.05, 95% CI -0.03 to 0.14; 2 studies; 87 participants; low-certainty evidence). No studies reported the discharge weight outcome. Early administration of AA may result in little to no difference in neurodevelopmental outcome assessed by Mental Developmental Index (MDI) of < 70 at two years of age (odds ratio 0.83, 95% CI 0.21 to 3.28; 1 study; 111 participants; low-certainty evidence). No studies reported all-cause mortality at 28 days and before discharge. Early administration of AA may result in a large increase in positive nitrogen balance in the first three days of life (MD 250.42, 95% CI 224.91 to 275.93; 4 studies; 93 participants; low-certainty evidence). AUTHORS' CONCLUSIONS: Low-certainty evidence suggests that there may be little to no difference between early and late administration of AA in growth (measured by length and head circumference during the first month after birth) and neurodevelopmental outcome (assessed by MDI of < 70). No RCTs reported on weight in the first month of life, mortality (all-cause mortality at 28 days and before discharge), or discharge weight. Low-certainty evidence suggests a large increase in positive nitrogen balance in preterm infants who received AA within 24 hours of birth. The clinical relevance of this observation is unknown. The number of infants in the RCTs included in the review was small, and there was clinical heterogeneity amongst trials. Adequately powered trials in infants < 37 weeks' gestation are required to determine optimal timing of initiation of AA. We identified two ongoing studies. Both studies will be recruiting infants ≥ 34 weeks of gestation and may or may not add to the outcome data for this review.


Assuntos
Aminoácidos , Recém-Nascido Prematuro , Recém-Nascido , Lactente , Humanos , Nutrição Parenteral , Idade Gestacional , Nitrogênio
4.
J Photochem Photobiol B ; 253: 112885, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38460431

RESUMO

The daily light/dark cycle affects animals' learning, memory, and cognition. Exposure to insufficient daylight illumination negatively impacts emotion and cognition, leading to seasonal affective disorder characterized by depression, anxiety, low motivation, and cognitive impairment in diurnal animals. However, how this affects memory, learning, and cognition in nocturnal rodents is largely unknown. Here, we studied the effect of daytime light illuminance on memory, learning, cognition, and expression of mRNA levels in the hippocampus, thalamus, and cortex, the higher-order learning centers. Two experiments were performed. In experiment one, rats were exposed to 12 L:12D (12 h light and 12 h dark) with a 10, 100, or 1000 lx daytime light illuminance. After 30 days, various behavioral tests (novel object recognition test, hole board test, elevated plus maze test, radial arm maze, and passive avoidance test) were performed. In experiment 2, rats since birth were raised either under constant bright light (250 lx; LL) or a daily light-dark cycle (12 L:12D). After four months, behavioral tests (novel object recognition test, hole board test, elevated plus maze test, radial arm maze, passive avoidance test, Morris water maze, and Y-maze tests) were performed. At the end of experiments, rats were sampled, and mRNA expression of Brain-Derived Neurotrophic Factor (Bdnf), Tyrosine kinase (Trk), microRNA132 (miR132), Neurogranin (Ng), Growth Associated Protein 43 (Gap-43), cAMP Response Element-Binding Protein (Crebp), Glycogen synthase kinase-3ß (Gsk3ß), and Tumour necrosis factor-α (Tnf-α) were measured in the hippocampus, cortex, and thalamus of individual rats. Our results show that exposure to bright daylight (100 and 1000 lx; experiment 1) or constant light (experiment 2) compromises memory, learning, and cognition. Suppressed expression levels of these mRNA were also observed in the hypothalamus, cortex, and thalamus. These results suggest that light affects differently to different groups of animals.


Assuntos
Cognição , MicroRNAs , Ratos , Animais , Ansiedade/metabolismo , Aprendizagem em Labirinto/fisiologia , Fotoperíodo , RNA Mensageiro/genética
5.
Artif Cells Nanomed Biotechnol ; 52(1): 186-200, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38465883

RESUMO

Green-mediated synthesis of nanoparticles has earned a promising role in the area of nanotechnology due to their biomedical applications. This study describes the synthesis of silver nanoparticles (AgNPs) using Mikania micrantha leaf extract and its functional activities against cancer. The synthesis of AgNPs was confirmed using Ultraviolet-Visible (UV-Vis) spectrum that exhibited an absorption band at 459 nm. The bioactive compounds of M. micrantha leaf extract that functioned as reducing and capping agents were confirmed by a shift in the absorption bands in Fourier Transform Infra-red Spectroscopy (FT-IR). Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) studies validated the spherical shape and size of AgNPs, respectively. Energy Dispersive Spectroscopy (EDS) analysis revealed the presence of elemental silver. The crystalline nature of AgNPs was confirmed by the X-ray Diffraction Analysis (XRD). AgNPs effectively induced cytotoxicity and prevented A549 cell colony formation in a dose-dependent manner. Treatment of A549 cells with AgNPs also increased DNA damage, which was coupled with elevated lipid peroxidation and decreased antioxidant enzymes such as glutathione (GSH), glutathione-s-transferase (GST), and superoxide dismutase (SOD). Following AgNPs treatment, the mRNA expression levels of the pro-apoptotic genes as well as the activities of caspases were significantly elevated in A549 cells while the expression levels of anti-apoptotic genes were downregulated. Our study demonstrates the potential of the synthesised AgNPs for cancer therapy possibly targeting the apoptotic pathway.


Assuntos
Adenocarcinoma de Pulmão , Nanopartículas Metálicas , Mikania , Humanos , Prata/farmacologia , Prata/química , Caspases , Nanopartículas Metálicas/química , Espectroscopia de Infravermelho com Transformada de Fourier , Apoptose , Glutationa , Adenocarcinoma de Pulmão/tratamento farmacológico , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Antibacterianos/farmacologia
6.
Nat Commun ; 15(1): 2439, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38499561

RESUMO

Probabilistic inference in data-driven models is promising for predicting outputs and associated confidence levels, alleviating risks arising from overconfidence. However, implementing complex computations with minimal devices still remains challenging. Here, utilizing a heterojunction of p- and n-type semiconductors coupled with separate floating-gate configuration, a Gaussian-like memory transistor is proposed, where a programmable Gaussian-like current-voltage response is achieved within a single device. A separate floating-gate structure allows for exquisite control of the Gaussian-like current output to a significant extent through simple programming, with an over 10000 s retention performance and mechanical flexibility. This enables physical evaluation of complex distribution functions with the simplified circuit design and higher parallelism. Successful implementation for localization and obstacle avoidance tasks is demonstrated using Gaussian-like curves produced from Gaussian-like memory transistor. With its ultralow-power consumption, simplified design, and programmable Gaussian-like outputs, our 3-terminal Gaussian-like memory transistor holds potential as a hardware platform for probabilistic inference computing.

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