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1.
Front Oral Health ; 5: 1343937, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38638174

RESUMO

Background: Mouthwashes play a pivotal role in oral care, and their efficacy has been explored extensively across various dimensions. As a contribution to the development of novel oral care products, this study aims to investigate the psychophysiological effects of aromatic mouthwashes during the resilience period from a short-term cognitive stressor utilizing biological signals and subjective evaluations. Methods: A within-participant experimental design with 22 healthy females was conducted with four mouthwashes; peppermint (Mint), peppermint + bergamot (MB), peppermint + sweet orange (MO), and peppermint + lavender (ML), and water as the control (Ctl), after a 20-min calculation task. Subjective evaluations and physiological responses including skin conductance level and electrocardiogram were recorded throughout the experiment. Results: Citrus mouthwashes (MO and MB) showed a greater decrease in heart rate and a significant increase in the high-frequency component of heart rate variability. The participants indicated a significant effect in terms of "flavor preference" and "refreshing sensation" for mouthwash use compared to the Ctl. Conclusion: The results suggest that rinsing with citrus-flavored mouthwashes has a positive impact in alleviating the physiological stress response (in terms of cardiac activity). These findings may have implications for the development of innovative, novel oral care products that promote stress reduction and improve oral health.

2.
Am J Biol Anthropol ; : e24925, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38487982

RESUMO

OBJECTIVES: Combining research from infant and child development, public health, anthropology, and history, this research examines the relationship between growth, growth disruption, and skeletal indicators of chronic and/or episodic physiological stress (stress) among juvenile individuals (n = 60) interred at the late antique infant and child cemetery at Poggio Gramignano (PG) (ca. 5th century CE), associated with a rural agricultural community. MATERIALS AND METHODS: Growth disruption-evidenced by decreased long bone length compared to dental age-and stress experience-evidenced by skeletal stress indicators-within these individuals are compared to those within juveniles from a comparative sample (n = 66) from two urban Roman-era cemeteries, Villa Rustica (VR) (0-250 CE) and Tragurium City Necropolis (TCN) (0-700 CE). RESULTS: Results indicate that individuals from PG had significantly smaller femoral lengths-for-age than those from VR and TCN; however, the frequency of skeletal stress indicators was higher among juveniles from VR and TCN. DISCUSSION: These differences in growth and stress experience are likely related to the different biosocial and ecological environments present in these two regions. For the community at PG, internal and external violent conflicts, as well as social, political, and economic turmoil, and subsistence shortages, endemic and epidemic infectious disease, nutritional deficiencies, and inherited or acquired anemia may have synergized to create chronically and/or episodically deleterious conditions for its juveniles.

3.
J Psychiatr Res ; 172: 156-163, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38382239

RESUMO

BACKGROUND: Stress plays an important role in the etiology of schizophrenia. However, the mechanisms by which chronic physiological stress and perceived stress relate to the clinical features of schizophrenia may differ. We aimed to elucidate the relationships among chronic physiological stress indexed by allostatic load (AL), perceived stress, and clinical symptoms in individuals with first-episode schizophrenia (FES). METHODS: Individuals with FES (n = 90, mean age = 28.26years old, 49%female) and healthy controls (111, 28.88, 51%) were recruited. We collected data of 13 biological indicators to calculate the AL index, assessed subjective stress with the Perceived Stress Scale-14 (PSS-14), and compared AL and perceived stress between groups. Patients with FES were also evaluated with the Positive and Negative Syndrome Scale (PANSS) and the Calgary Depression Scale for Schizophrenia (CDSS). RESULTS: Individuals with FES had higher AL and PSS score than healthy controls. There were no significant correlations between AL and PSS score in either patients or controls. Among individuals with FES, the AL index was associated with the severity of positive symptoms, while the PSS score was positively associated with CDSS score. Both elevated AL and PSS were correlated with the occurrence of schizophrenia. CONCLUSIONS: Physiological stress, as reflected by AL, may be more related to positive symptoms, while perceived stress appear to be associated with depressive symptoms in individuals with FES. Longitudinal studies are necessary to explore the relationships between interventions for different stressor types and specific clinical outcomes in FES.


Assuntos
Alostase , Testes Psicológicos , Esquizofrenia , Autorrelato , Humanos , Feminino , Adulto , Esquizofrenia/complicações , Alostase/fisiologia , Escalas de Graduação Psiquiátrica , 60679
4.
Biol Psychol ; 186: 108762, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38311307

RESUMO

Valid approaches to conveniently measure stress reactivity are needed due to the growing evidence of its health-impairing effects. This study examined whether the Perceived Stress Reactivity Scale (PSRS) predicts cardiovascular and psychological responses to psychosocial stressors during daily life and during a virtual reality (VR) Trier Social Stress Test (TSST). Medical students answered a standardized baseline questionnaire to assess perceived stress reactivity by the PSRS. The PSRS asks participants to rate the intensity of their typical affective responses to common stressors during daily life. They were further asked to participate in a VR-TSST and in an ecological momentary assessment (EMA) over a period of three consecutive workdays during daily life. Blood pressure and self-reported stress were repeatedly, heart rate variability (HRV) continuously measured during the VR-TSST and EMA. Furthermore, participants repeatedly assessed task demands, task control and social conflict during the EMA. Data was analysed using multilevel analysis and multiple linear regression. Results indicate that the PSRS moderates associations between blood pressure (but not HRV) and demands and control during daily life. Furthermore, the PSRS directly predicted self-reported stress, but did not moderate associations between self-reported stress and demands, control and social conflict. The PSRS did not predict physiological and self-reported stress responses to the VR-TSST. This study partly confirmed convergent validity of the PSRS to stress reactivity in daily life. Furthermore, the lack of association between the PSRS and stress responses to the VR-TSST calls for future studies to search for reliable and valid ways to assess stress reactivity.


Assuntos
Avaliação Momentânea Ecológica , Realidade Virtual , Humanos , Autorrelato , Estresse Psicológico/psicologia , Testes Psicológicos , Hidrocortisona/análise
5.
Mar Environ Res ; 196: 106402, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38402778

RESUMO

Cephalopods receive a great deal of attention due to their socioeconomically important fisheries and aquaculture industries as well their unique biological features. However, basic information about their physiological responses under stress conditions is lacking. This study investigated the impact of a simple stressor, exercise to exhaustion, on the activity levels of antioxidant enzymes and the concentrations of molecules involved in oxidative stress response in the pale octopus (Octopus pallidus). Eight biochemical assays were measured in the humoral (plasma) and cellular (hemocyte) components of O. pallidus haemolymph, the invertebrate analogue to vertebrate blood. Overall, exercise resulted in an increase in activity of plasma catalase (CAT) and glutathione-S-transferase (GST) and the decrease in activity of plasms glutathione reductase (GR). In the hemocytes, the exercise elicited a different response, with a reduction in the activity of superoxide dismutase (SOD), GR, and glutathione peroxidase (GPX) and a reduction in nitric oxide (NO) concentration. Malondialdehyde (MDA) activity was similar in the plasma and haemocytes in control and exercised treatments, indicating that exercise did not induce lipid peroxidation. These results provide an important baseline for understanding oxidative stress in octopus, with exercise to exhaustion serving as a simple stressor which will ultimately inform our ability to detect and understand physiological responses to more complex stressors.


Assuntos
Octopodiformes , Animais , Octopodiformes/metabolismo , Antioxidantes , Estresse Oxidativo , Catalase/metabolismo , Superóxido Dismutase/metabolismo , Glutationa Peroxidase/metabolismo , Peroxidação de Lipídeos , Glutationa Redutase/metabolismo , Glutationa Transferase/metabolismo , Glutationa/metabolismo
6.
J Aging Phys Act ; : 1-12, 2024 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-38340712

RESUMO

Physical function is regarded as the cornerstone of healthy aging, and exercise is an important determinant of healthy aging. This study examined the feasibility and physiological (heart rate, blood pressure, blood lactate, and rate of perceived exertion) and psychological (enjoyment) response resulting from an acute progressive sled-push (SLP) exercise session using the novel XPO Sled Trainer in older adults and compared that with walking (WKC) condition. The exercise session comprised six exercise bouts at 75%, 85%, 100% (2×), and 125% (2×) of normal velocity with a 2-min rest between bouts. Thirty-six older adults were randomly allocated into either the SLP or WKC conditions. No adverse events were observed during the exercise session, and all participants completed the exercise protocol as prescribed. One-third of the participants in the SLP group reported minimal body discomfort. Significantly higher responses were observed for all physiological variables as the intensity of the exercise increased in the SLP group compared with the WKC group (p < .001). The SLP group presented a decline in enjoyment as the intensity of the exercise increased (during), but similar enjoyment level than the WKC group for the overall exercise session (p = .711). Our findings support the viability and safety of SLP exercise using the XPO Sled Trainer in older adults. Such exercise demonstrated an intensity-driven modality that may have potential to elucidate positive adaptations in the cardiovascular system of older adults with acceptable levels of enjoyment.

7.
Evol Appl ; 17(2): e13663, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38390377

RESUMO

Climate-induced expansion of invasive hybridization (breeding between invasive and native species) poses a significant threat to the persistence of many native species worldwide. In the northern U.S. Rocky Mountains, hybridization between native cutthroat trout and non-native rainbow trout has increased in recent decades due, in part, to climate-driven increases in water temperature. It has been postulated that invasive hybridization may enhance physiological tolerance to climate-induced thermal stress because laboratory studies indicate that rainbow trout have a higher thermal tolerance than cutthroat trout. Here, we assessed whether invasive hybridization improves cardiac performance response to acute water temperature stress of native wild trout populations. We collected trout from four streams with a wide range of non-native admixture among individuals and with different temperature and streamflow regimes in the upper Flathead River drainage, USA. We measured individual cardiac performance (maximum heart rate, "MaxHR", and temperature at arrhythmia, "ArrTemp") during laboratory trials with increasing water temperatures (10-28°C). Across the study populations, we observed substantial variation in cardiac performance of individual trout when exposed to thermal stress. Notably, we found significant differences in the cardiac response to thermal regimes among native cutthroat trout populations, suggesting the importance of genotype-by-environment interactions in shaping the physiological performance of native cutthroat trout. However, rainbow trout admixture had no significant effect on cardiac performance (MaxHR and ArrTemp) within any of the three populations. Our results indicate that invasive hybridization with a warmer-adapted species does not enhance the cardiac performance of native trout under warming conditions. Maintaining numerous populations across thermally and hydrologically diverse stream environments will be crucial for native trout to adapt and persist in a warming climate.

8.
Environ Res ; 249: 118432, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38354885

RESUMO

Prenatal fine particulate matter (PM2.5) and maternal psychological functioning have been associated with child cognitive outcomes, though their independent and joint impacts on earlier behavioral outcomes remains less studied. We used data from 382 mother-child pairs from a prospective birth cohort in Mexico City. Temperament was measured at 24 months using the Carey Toddler Temperament Scale (TTS). Exploratory factor analysis (EFA) was used to update the factor structure of the TTS. During pregnancy, mothers completed the Crisis in Family Systems-Revised, Edinburgh Depression Scale, pregnancy-specific anxiety scale, and the Perceived Stress Scale. Pregnancy PM2.5 was assessed using estimates from a satellite-based exposure model. We assessed the association between prenatal maternal stress and PM2.5 on temperament, in both independent and joint models. Quantile g-computation was used to estimate the joint associations. Models were adjusted for maternal age, SES, education, child sex, and child age. In EFA, we identified three temperament factors related to effortful control, extraversion, and negative affect. Our main results showed that higher levels of PM2.5 and several of the maternal psychological functioning measures were related to both effortful control and negative affect in the child, both individually and as a mixture. For instance, a one quartile increase in the prenatal mixture was associated with higher negative affect scores in the child (0.34, 95% CI: 0.16, 0.53). We observed modification of these associations by maternal SES, with associations seen only among lower SES participants for both effortful control (-0.45, 95% CI: -0.70, -0.20) and negative affect outcomes (0.60, 95% CI: 0.35, 0.85). Prenatal PM2.5 and maternal psychological functioning measures were associated with toddler temperament outcomes, providing evidence for impacts of chemical and non-chemical stressors on early child health.

9.
Enferm. glob ; 23(73): 182-205, ene. 2024. tab
Artigo em Espanhol | IBECS | ID: ibc-228893

RESUMO

Introducción: En Latinoamérica el consumo de bebidas alcohólicas es causante de problemas relacionados con la salud física, mental y social. La Comisión Nacional para el Desarrollo de los Pueblos Indígenas señala que las poblaciones indígenas son vulnerables a presentar problemas con el consumo de alcohol derivado de algunas características como pobreza extrema y rezago educativo, nuestro objetivo fue conocer el efecto del estrés percibido sobre el consumo de alcohol en una población indígena. Material y método: El diseño del estudio fue descriptivo, correlacional, predictivo. Resultados: El estrés percibido se relacionó positiva y significativamente con el número de copas consumidas en un día típico (rs = .211, p‹.01), y con el consumo de alcohol AUDIT (rs= .328, p ‹ .01), sin embargo, se relacionó negativa y significativamente con la edad (rs = -.135, p ‹.05). El Modelo final presentó un efecto significativo en la totalidad del modelo (F (1,110) = 20.126, p = .001), explica el 39.3% de la varianza del consumo de alcohol. Se encontró que el estrés percibido tuvo un efecto positivo y significativo sobre el consumo de alcohol (B =.229, p ‹ .001). Conclusiones: El estrés percibido es un factor que influye en el consumo excesivo de alcohol en las poblaciones indígenas, se considera que el consumo de drogas es una estrategia de afrontamiento para hacer frente a problemas estresantes en la vida diaria. La población presento problemas con el consumo de alcohol excesivo episódico, prevalencias altas en consumo en el último año y consumo dañino (AU)


Introduction: In Latin America, alcoholic beverages consumption is a main reason of problems related to physical, mental and social health. The National Commission for the Development of Indigenous Peoples states that indigenous populations are vulnerable problems related to alcohol consumption because a set of characteristics such as extreme poverty and educational backwardness. Our objective was to determine the effect of perceived stress on alcohol consumption in an indigenous population.Method: Study design was descriptive, correlational, and predictive.Results: Perceived stress was positively and significantly related to the number of drinks consumed in a typical day (rs = .211, p‹.01), it’s also related with alcohol consumption (AUDIT) (rs= .328, p ‹ .01), however, it was negatively and significantly related to age (rs = -.135, p ‹.05). The final Model presented a significant effect in the whole model (F (1,110) = 20.126, p = .001), explaining 39.3% of the variance of alcohol consumption. Perceived stress was found to have a positive and significant effect on alcohol consumption (B =.229, p ‹ .001).Conclusions: Perceived stress is a factor influencing excessive alcohol consumption in indigenous populations, drug use is considered a coping strategy to deal with stressful problems in daily life. The population presented problems with heavy episodic drinking, past year drinking with high prevalence and harmful drinking (AU)


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Consumo de Bebidas Alcoólicas/psicologia , Estresse Psicológico , 50227 , Consumo de Bebidas Alcoólicas , México
10.
Logoped Phoniatr Vocol ; : 1-10, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38225800

RESUMO

Presentations to audiences are often seen as challenging by university students, causing physiological reactivity on cortisol levels and heart rate, for example. Many students perceive that they have difficulties expressing themselves or do not consider themselves to be good communicators. With the thought that efficient communication is able to bring well-being and more confidence, it is understood that a communication skills training could mitigate adverse effects on the body during public speaking. This study aimed to verify whether a communicational improvement training can improve physiological parameters and perception when speaking in public among university students. This was a prospective, blinded, controlled, and randomized trial. Students from colleges and universities were recruited for this study. Invitations were either in person or via social networks and/or e-mail. There were 39 university students who completed the tasks, ages between 18 and 30. There were two groups: the intervention group (IG) and control group (CG). The intervention group participated in a communicational improvement program for six weeks to work on breathing, articulation, speech rhythm, pneumophonoarticulatory coordination, expressiveness and non-verbal communication. Data of heart rate measures, salivary cortisol analysis, self-perception of public speaking, and presentation ratings were collected. The intervention group presented with lower heart rates and cortisol levels, better presentation ratings, and higher self-perception of public speaking than the control group after participating in the communication improvement training. In this study it was possible to verify the efficiency of a communicational improvement training, being able to improve cortisol levels, heart rate, and perception when speaking in public in university students. Based on the results presented, new studies are suggested: (a) measuring the individual effect of the workshops demonstrated here and (b) comparing this type of intervention with other types of treatment used in the health area (medication, psychotherapeutic, holistic, etc.).

11.
J Vet Intern Med ; 38(1): 398-410, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38174810

RESUMO

BACKGROUND: Echocardiographic measurements are important prognostic indicators but might be influenced by heart rate and blood pressure. This is particularly important when comparing repeated examinations. HYPOTHESIS: To determine the effect of physiological stress at mildly increased heart rates and pharmacological challenge using IV administration of N-butylscopolammonium bromide and metamizol sodium on heart rate, blood pressure, and echocardiographic measurements. ANIMALS: Twenty healthy Warmblood horses. METHODS: Randomized crossover study. Horses were examined echocardiographically by 2-dimensional, M-mode, pulsed wave (PW) Doppler, and PW tissue Doppler imaging with simultaneous ECG recording and noninvasive blood pressure measurements during rest, physiological stress, and pharmacological challenge. Cardiac dimensions and functions were measured by a blinded observer. Data were analyzed using repeated-measures analysis of variance. RESULTS: Mean heart rate and arterial blood pressure were significantly higher during physiological stress (46 ± 2 bpm, 93 ± 16 mm Hg) and pharmacological challenge (62 ± 13 bpm, 107 ± 17 mm Hg) compared with rest (34 ± 3 bpm, 86 ± 12 mm Hg; P < .05). Compared with rest, physiological stress resulted in increased left atrial fractional area change (34.3 ± 7.5 vs 27.3 ± 5.1%; P = .01) and left ventricular late diastolic radial wall motion velocity (13 ± 3 vs 10 ± 2 cm/s; P = .01) but had no significant effect on most other echocardiographic variables. Compared with rest, pharmacological challenge led to significantly decreased left atrial and diastolic ventricular dimensions (left ventricular internal diameter: 10.3 ± 0.9 vs 10.7 ± 0.8 cm; P = .01), increased aortic and pulmonary diameters, and ventricular wall thickness. CONCLUSIONS AND CLINICAL IMPORTANCE: Physiological stress at mildly increased heart rates significantly enhanced atrial pump function. Larger heart rate and blood pressure increases during pharmacological challenge resulted in altered cardiac dimensions. This should be taken into account when evaluating echocardiographic measurements at increased heart rates.


Assuntos
Ecocardiografia , Doenças dos Cavalos , Cavalos , Animais , Frequência Cardíaca , Pressão Sanguínea , Estudos Cross-Over , Ecocardiografia/veterinária , Ecocardiografia/métodos , Ventrículos do Coração/diagnóstico por imagem , Taquicardia/veterinária
12.
Environ Pollut ; 345: 123329, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38281572

RESUMO

The biological pathways linking lead exposure to adverse outcomes are beginning to be understood. Rodent models suggest lead exposure induces dysfunction within the hypothalamic-pituitary-adrenal (HPA) axis and glucocorticoid regulation, a primary physiological stress response system. Over time, HPA axis and glucocorticoid dysfunction has been associated with adverse neurocognitive and cardiometabolic health, much like lead exposure. This systematic review utilized PRISMA guidelines to synthesize the literature regarding associations between lead exposure and downstream effector hormones of the HPA axis, including cortisol, a glucocorticoid, and dehydroepiandrosterone (DHEA), a glucocorticoid antagonist. We additionally determined the state of the evidence regarding lead exposure and allostatic load, a measure of cumulative body burden resultant of HPA axis and glucocorticoid dysfunction. A total of 18 articles were included in the review: 16 assessed cortisol or DHEA and 3 assessed allostatic load. Generally, the few available child studies suggest a significant association between early life lead exposure and altered cortisol, potentially suggesting the impact of developmental exposure. In adulthood, only cross sectional studies were available. These reported significant associations between lead and reduced cortisol awakening response and increased cortisol reactivity, but few associations with fasting serum cortisol. Two studies reported significant associations between increasing lead exposure and allostatic load in adults and another between early life lead exposure and adolescent allostatic load. The paucity of studies examining associations between lead exposure and allostatic load or DHEA and overall heterogeneity of allostatic load measurements limit conclusions. However, these findings cautiously suggest associations between lead and dysregulation of physiological stress pathways (i.e., glucocorticoids) as seen through cortisol measurement in children and adults. Future research would help to elucidate these associations and could further examine the physiological stress pathway as a mediator between lead exposure and detrimental health outcomes.


Assuntos
Glucocorticoides , Hidrocortisona , Adulto , Criança , Adolescente , Humanos , Glucocorticoides/toxicidade , Glucocorticoides/metabolismo , Hidrocortisona/metabolismo , Chumbo/toxicidade , Chumbo/metabolismo , Sistema Hipotálamo-Hipofisário , Estudos Transversais , Sistema Hipófise-Suprarrenal/metabolismo , Estresse Fisiológico , Desidroepiandrosterona/metabolismo , Estresse Psicológico
13.
J Appl Physiol (1985) ; 136(1): 33-42, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37994415

RESUMO

Exercise in hypoxia increases immune responses compared with normoxic exercise, and while Toll-like receptor 4 (TLR4) is implicated in these responses, its regulation remains undefined. The purpose of this study was to 1) investigate TLR4 regulation during workload-matched endurance exercise in normoxic and hypoxic conditions in vivo and 2) determine the independent effects of hypoxia and muscle contractions on TLR4 expression in vitro. Eight recreationally active men cycled for 1 h at 65% of their V̇o2max in normoxia (630 mmHg) and in hypobaric hypoxia (440 mmHg). Exercise in normoxia decreased TLR4 expressed on peripheral blood mononuclear cells (PBMCs), had no effect on the expression of inhibitor of κBα (IκBα), and increased the concentration of soluble TLR4 (sTLR4) in circulation. In contrast, exercise in hypoxia decreased the expression of TLR4 and IκBα in PBMCs, and sTLR4 in circulation. Markers of physiological stress were higher during exercise in hypoxia, correlating with markers of intestinal barrier damage, circulating lipopolysaccharides (LPS), and a concurrent decrease in circulating sTLR4, suggesting heightened TLR4 activation, internalization, and degradation in response to escalating physiological strain. In vitro, both hypoxia and myotube contractions independently, and in combination, reduced TLR4 expressed on C2C12 myotubes, and these effects were dependent on hypoxia-inducible factor 1 (HIF-1). In summary, the regulation of TLR4 varies depending on the physiological stress during exercise. To our knowledge, our study provides the first evidence of exercise-induced effects on sTLR4 in vivo and highlights the essential role of HIF-1 in the reduction of TLR4 during contraction and hypoxia in vitro.NEW & NOTEWORTHY We provide the first evidence of exercise affecting soluble Toll-like receptor 4 (sTLR4), a TLR4 ligand decoy receptor. We found that the degree of exercise-induced physiological stress influences TLR4 regulation on peripheral blood mononuclear cells (PBMCs). Moderate-intensity exercise reduces PBMC TLR4 and increases circulating sTLR4. Conversely, workload-matched exercise in hypoxia induces greater physiological stress, intestinal barrier damage, circulating lipopolysaccharides, and reduces both TLR4 and sTLR4, suggesting heightened TLR4 activation, internalization, and degradation under increased strain.


Assuntos
Leucócitos Mononucleares , Receptor 4 Toll-Like , Masculino , Humanos , Receptor 4 Toll-Like/metabolismo , Leucócitos Mononucleares/metabolismo , Inibidor de NF-kappaB alfa , Carga de Trabalho , Hipóxia , Lipopolissacarídeos/farmacologia
14.
Protoplasma ; 261(2): 227-243, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37665420

RESUMO

Monoterpenes are the main component in essential oils of Lippia alba. In this species, the chemical composition of essential oils varies with genome size: citral (geraniol and neral) is dominant in diploids and tetraploids, and linalool in triploids. Because environmental stress impacts various metabolic pathways, we hypothesized that stress responses in L. alba could alter the relationship between genome size and essential oil composition. Water stress affects the flowering, production, and reproduction of plants. Here, we evaluated the effect of water stress on morphophysiology, essential oil production, and the expression of genes related to monoterpene synthesis in diploid, triploid, and tetraploid accessions of L. alba cultivated in vitro for 40 days. First, using transcriptome data, we performed de novo gene assembly and identified orthologous genes using phylogenetic and clustering-based approaches. The expression of candidate genes related to terpene biosynthesis was estimated by real-time quantitative PCR. Next, we assessed the expression of these genes under water stress conditions, whereby 1% PEG-4000 was added to MS medium. Water stress modulated L. alba morphophysiology at all ploidal levels. Gene expression and essential oil production were affected in triploid accessions. Polyploid accessions showed greater growth and metabolic tolerance under stress compared to diploids. These results confirm the complex regulation of metabolic pathways such as the production of essential oils in polyploid genomes. In addition, they highlight aspects of genotype and environment interactions, which may be important for the conservation of tropical biodiversity.


Assuntos
Monoterpenos Acíclicos , Lippia , Óleos Voláteis , Verbenaceae , Lippia/genética , Lippia/química , Triploidia , Desidratação , Filogenia , Óleos Voláteis/química
15.
J Biomech ; 162: 111894, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38070295

RESUMO

INTRODUCTION: The pathomechanism of low back pain (LBP) remains unknown. However, changes to mechanical properties of soft tissues affected by LBP may indicate the presence of stress shielding, which may manifest via tissue remodeling. This study investigates the potential for physiological stress shielding within the lumbar spine by examining differences within lumbar soft tissue morphology between control and LBP subjects. METHODS: Through MRI, the total and functional cross-sectional area (tCSA, fCSA) and fatty infiltration (FI) of the lumbar multifidus (MF), erector spinae (ES), quadratus lumborum (QL), psoas major (PM), and thoracolumbar fascia (TLF) were measured from the L1/L2 to L5/S1 intervertebral disc levels of 69 subjects (36 LBP and 33 control subjects). Statistical analysis was conducted using Mann-Whitney U. P < 0.05 denoted significance. RESULTS: Comparison of male LBP patients and male healthy controls yielded an increase in tCSA and fCSA within the L4/L5 PM (p < 0.01), and the L4/L5 ES (p = 0.02) and PM (p < 0.01), respectively, of LBP patients. Female LBP patients' FI compared to female controls increased within the L1/L2 MF (p = 0.03), L3/L4 MF (p = 0.04) and ES (p = 0.02), and L4/L5 QL (p = 0.01). The L3/L4 TLF also demonstrated an 8% increase in LBP subjects. CONCLUSION: Male patients' results suggest elevated tissue loading during motion yielding hypertrophy in the L4/L5 ES and PM fCSA, and PM tCSA. Female LBP patients' MF, ES, and PM at L3/L4 demonstrating elevated FI coupled with TLF tCSA hypertrophy may suggest irregular stress distributions and lay the foundation for stress shielding within musculoskeletal soft tissues.


Assuntos
Dor Lombar , Salicilanilidas , Humanos , Masculino , Feminino , Vértebras Lombares/diagnóstico por imagem , Região Lombossacral , Imageamento por Ressonância Magnética/métodos , Hipertrofia
16.
Environ Pollut ; 343: 123180, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38142812

RESUMO

Ozone (O3) pollution is harmful to plants and ecosystems. Several chemicals have been evaluated to protect plants against O3 deleterious effects. However, they are not adequately efficient and/or the environmental safety of their application is questioned. Hence, new chemicals that provide sufficient protection while being safer for environmental application are needed. This study investigates the response of two O3-sensitive plant species (Phaseolus vulgaris L. cv. Pinto and Nicotiana tabacum L. cv. Bel-W3) leaf-sprayed with deionized water (W, control), ethylenediurea (EDU, 1 mM) or melatonin at lower (1 mM) or higher (3 mM) concentrations (Mel_L and Mel_H, respectively), and then exposed to a square wave of 200 ppb O3, lasting 1 day (5 h day-1) for bean and 2 days (8 h day-1) for tobacco. In both species, the photosynthetic activity of O3-exposed plants was about halved. O3-induced membrane damage was also confirmed by increased malondialdehyde (MDA) byproducts compared to control (W). In EDU- and Mel-treated bean plants, the photosynthetic performance was not influenced by O3, leading to reduction of the incidence and severity of O3 visible injury. In bean plants, Mel_L mitigated the detrimental effect of O3 by boosting antioxidant enzyme activities or osmoprotectants (e.g. abscisic acid, proline, and glutathione transferase). In Mel_L-sprayed tobacco plants, O3 negatively influenced the photosynthetic activity. Conversely, Mel_H ameliorated the O3-induced oxidative stress by preserving the photosynthetic performance, preventing membrane damage, and reducing the visible injuries extent. Although EDU performed better, melatonin protected plants against O3 phytotoxicity, suggesting its potential application as a bio-safer and eco-friendlier phytoprotectant against O3. It is worth noting that the content of melatonin in EDU-treated plants remained unchanged, indicating that the protectant mode of action of EDU is not Mel-related.


Assuntos
Poluentes Atmosféricos , Melatonina , Ozônio , Antioxidantes/farmacologia , Tabaco , Melatonina/farmacologia , Ozônio/toxicidade , Ecossistema , Plantas , Poluentes Atmosféricos/toxicidade
17.
Animals (Basel) ; 13(21)2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37958139

RESUMO

Many reptiles are maintained in captivity and heavily traded, although welfare measures for many species are not well established and are under-researched compared to other animals. In this study, we focused on two of these species: crested geckos (Correlophus ciliatus) and leopard geckos (Eublepharis macularius). To better interpret their behavior in captivity, the individual reaction to novel objects and the fecal glucocorticoid metabolite levels were measured in an attempt to identify the potential correlation between them. Also, we explored if some characteristic of the objects (e.g., color, shape, or smell) resulted in being more attractive to some species and/or individuals. Equivalent responses to different objects were not obtained for all the geckos, the behavioral response being highly individual and context-dependent, although modulated by the species. Individuals which manipulated earlier and interacted longer with novel objects showed lower basal fecal corticosterone metabolite (FCM) levels. Differences according to the species suggested that crested geckos have significantly greater and more variable FCM levels than leopard geckos. Our results can help to understand the reaction of geckos to novelty and have the potential to serve in their welfare assessment, although more studies are needed to proper establish welfare protocols.

18.
Artigo em Inglês | MEDLINE | ID: mdl-38000946

RESUMO

OBJECTIVE: Study and Evaluation of Two Scores: Shock Index (SI) and Physiological Stress Index (PSI) as discriminators for proactive treatment (reperfusion before decompensated shock) in a population of intermediate-high risk pulmonary embolism (PE). DESIGN: Using a database from a retrospective cohort with clinical variables and the outcome variable of "proactive treatment", a comparison of the populations was conducted. Optimal cut-off for "proactive treatment" points were obtained according to the SI and PSI. Comparisons were carried out based on the cut-off points of both indices. SETTING: Patients admitted to a mixed ICU for PE. PARTICIPANTS: Patients >18 years old admitted to the ICU with intermediate-high risk PE recruited from January 2015 to October 2022. INTERVENTIONS: None. MAIN VARIABLES OF INTEREST: Population comparison and metrics regarding predictive capacity when determining proactive treatment. RESULTS: SI and PSI independently have a substandard predictive capacity for discriminating patients who may benefit from an early reperfusion therapy. However, their combined use improves detection of sicker intermediate-high risk PE patients (Sensitivity = 0.66) in whom an early reperfusion therapy may improve outcomes (Specificity = 0.9). CONCLUSIONS: The use of the SI and PSI in patients with intermediate-high risk PE could be useful for selecting patients who would benefit from proactive treatment.

19.
Saudi J Biol Sci ; 30(11): 103836, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37920797

RESUMO

The present study aimed to determine the effect of repeated heat stress on serum levels of cortisol (CORT), acute phase proteins (APP) and heat shock protein (HSP) 70, haematological indicators, and electroencephalographic (EEG) response in the native Katjang and exotic Boer goats. Six female Katjang (15.7 kg ± 0.68) and six female Boer (16.8 kg ± 1.16) goats aged 5 to 6 months old were exposed to 38 ± 1℃ for 8 h, and the procedure was repeated at three different weeks (weeks 1, 2 and 3). Measurements of rectal temperatures and EEG activity and collection of blood samples were conducted before heat exposure (0 h), immediately after the heat exposure (8 h), and 8 h after completion of heat exposure (16 h) (recovery period). The current results revealed that the Boer animals had significantly higher rectal temperatures (RT), haemoglobin (Hb) and packed cell volume (PCV) counts than their Kajang counterparts. There were significant breed × stage of heat treatment (SHT) × week of heat treatment (WHT) interactions for neutrophil to lymphocyte ratios (NLR). In general, the Katjang animals had elevated NLR compared to those of Boer. The Boer goats had reduced capacity to express serum HSP70 compared to their Katjang counterparts following the heat challenge at week 3. Boer goats demonstrated higher delta waves than the Katjang group, which suggested the former were more stressed following the heat exposure. Breed had a negligible effect on CORT, APP, WBC counts and backfat thickness. Our findings suggested that the Katjang breed, as measured by RT, HB and PCV count, and EEG activity, could be more tolerant to heat stress than Boer. The Katjang goats showed higher HSP70 expression than their Boer counterparts, suggesting improved thermoregulation in the former.

20.
Front Netw Physiol ; 3: 1289983, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38020243

RESUMO

In the study of synchronization dynamics between interacting systems, several techniques are available to estimate coupling strength and coupling direction. Currently, there is no general 'best' method that will perform well in most contexts. Inter-system recurrence networks (IRN) combine auto-recurrence and cross-recurrence matrices to create a graph that represents interacting networks. The method is appealing because it is based on cross-recurrence quantification analysis, a well-developed method for studying synchronization between 2 systems, which can be expanded in the IRN framework to include N > 2 interacting networks. In this study we examine whether IRN can be used to analyze coupling dynamics between physiological variables (acceleration, blood volume pressure, electrodermal activity, heart rate and skin temperature) observed in a client in residential care with severe to profound intellectual disabilities (SPID) and their professional caregiver. Based on the cross-clustering coefficients of the IRN conclusions about the coupling direction (client or caregiver drives the interaction) can be drawn, however, deciding between bi-directional coupling or no coupling remains a challenge. Constructing the full IRN, based on the multivariate time series of five coupled processes, reveals the existence of potential feedback loops. Further study is needed to be able to determine dynamics of coupling between the different layers.

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