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1.
J Neurosci ; 44(13)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38302441

RESUMO

Ocular position drifts during gaze fixation are significantly less well understood than microsaccades. We recently identified a short-latency ocular position drift response, of ∼1 min arc amplitude, that is triggered within <100 ms by visual onsets. This systematic eye movement response is feature-tuned and seems to be coordinated with a simultaneous resetting of the saccadic system by visual stimuli. However, much remains to be learned about the drift response, especially for designing better-informed neurophysiological experiments unraveling its mechanistic substrates. Here we systematically tested multiple new feature tuning properties of drift responses. Using highly precise eye tracking in three male rhesus macaque monkeys, we found that drift responses still occur for tiny foveal visual stimuli. Moreover, the responses exhibit size tuning, scaling their amplitude (both up and down) as a function of stimulus size, and they also possess a monotonically increasing contrast sensitivity curve. Importantly, short-latency drift responses still occur for small peripheral visual targets, which additionally introduce spatially directed modulations in drift trajectories toward the appearing peripheral stimuli. Drift responses also remain predominantly upward even for stimuli exclusively located in the lower visual field and even when starting gaze position is upward. When we checked the timing of drift responses, we found it was better synchronized to stimulus-induced saccadic inhibition than to stimulus onset. These results, along with a suppression of drift response amplitudes by peristimulus saccades, suggest that drift responses reflect the rapid impacts of short-latency and feature-tuned visual neural activity on final oculomotor control circuitry in the brain.


Assuntos
Fixação Ocular , Visão Ocular , Animais , Masculino , Macaca mulatta , Movimentos Oculares , Movimentos Sacádicos , Percepção Visual/fisiologia
2.
J Neurosci ; 2022 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-35940874

RESUMO

In severely affected stroke survivors, cortico-muscular control is disturbed and volitional upper limb movements often absent. Mental rehearsal of the impaired movement in conjunction with sensory feedback provision are suggested as promising rehabilitation exercises. Knowledge about the underlying neural processes, however, remains vague. In male and female chronic stroke patients with hand paralysis, a brain-computer interface controlled a robotic orthosis and turned sensorimotor beta-band desynchronization during motor imagery (MI) of finger extension into contingent hand opening. Healthy control subjects performed the same task and received the same proprioceptive feedback with a robotic orthosis or visual feedback only. Only when proprioceptive feedback was provided, cortico-muscular coherence (CMC) increased with a predominant information flow from the sensorimotor cortex to the finger extensors. This effect (i) was specific to the beta frequency-band, (ii) transferred to a motor task, (iii) was proportional to subsequent corticospinal excitability and correlated with behavioral changes in the (iv) healthy and (v) post-stroke condition; notably, MI-related enhancement of beta-band CMC in the ipsilesional premotor cortex correlated with motor improvements after the intervention.In the healthy and injured human nervous system, synchronized activation of motor-related cortical and spinal neural pools facilitates, in accordance with the communication-through-coherence hypothesis, cortico-spinal communication and may, thereby, be therapeutically relevant for functional restoration after stroke, when voluntary movements are no longer possible.Significance statement:This study provides insights into the neural processes that transfer effects of brain-computer interface neurofeedback to subsequent motor behavior. Specifically, volitional control of cortical oscillations and proprioceptive feedback enhances both cortical activity and behaviorally relevant connectivity to the periphery in a topographically circumscribed and frequency-specific way. This enhanced cortico-muscular control can be induced in the healthy and post-stroke brain. Thereby, activating the motor cortex with mental rehearsal of the impaired movement and closing the loop by robot-assisted feedback synchronizes ipsilesional premotor cortex and spinal neural pools in the beta-frequency band. This facilitates, in accordance with the communication-through-coherence hypothesis, cortico-spinal communication and may, thereby, be therapeutically relevant for functional restoration after stroke, when voluntary movements are no longer possible.

3.
Neuroimage ; 269: 119891, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36706940

RESUMO

The ratio between the input and output of neuronal populations, usually referred to as gain modulation, is rhythmically modulated along the oscillatory cycle. Previous research on spinal neurons, however, revealed contradictory findings: both uni- and bimodal patterns of increased responsiveness for synaptic input have been proposed for the oscillatory beta rhythm. In this study, we compared previous approaches of phase estimation directly on simulated data and empirically tested the corresponding predictions in healthy males and females. We applied single-pulse transcranial magnetic stimulation over the primary motor cortex at rest, and assessed the spinal output generated by this input. Specifically, the peak-to-peak amplitude of the motor evoked potential in the contralateral forearm was estimated as a function of the EMG phase at which the stimulus was applied. The findings indicated that human spinal neurons adhere to a unimodal pattern of increased responsiveness, and suggest that the rising phase of the upper beta band maximizes gain modulation. Importantly, a bimodal pattern of increased responsiveness was shown to result in an artifact during data analysis and filtering. This observation of invalid preprocessing could be generalized to other frequency bands (i.e., delta, theta, alpha, and gamma), different task conditions (i.e., voluntary muscle contraction), and EEG-based phase estimations. Appropriate analysis algorithms, such as broad-band filtering, enable us to accurately determine gain modulation of neuronal populations and to avoid erroneous phase estimations. This may facilitate novel phase-specific interventions for targeted neuromodulation.


Assuntos
Córtex Motor , Tratos Piramidais , Masculino , Feminino , Humanos , Tratos Piramidais/fisiologia , Córtex Motor/fisiologia , Potencial Evocado Motor/fisiologia , Estimulação Magnética Transcraniana , Ritmo beta/fisiologia , Músculo Esquelético/fisiologia , Eletromiografia
4.
J Neurophysiol ; 130(5): 1282-1302, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37818591

RESUMO

Saccadic inhibition refers to a short-latency transient cessation of saccade generation after visual sensory transients. This oculomotor phenomenon occurs with a latency that is consistent with a rapid influence of sensory responses, such as stimulus-induced visual bursts, on oculomotor control circuitry. However, the neural mechanisms underlying saccadic inhibition are not well understood. Here, we exploited the fact that macaque monkeys experience robust saccadic inhibition to test the hypothesis that inhibition time and strength exhibit systematic visual feature tuning properties to a multitude of visual feature dimensions commonly used in vision science. We measured saccades in three monkeys actively controlling their gaze on a target, and we presented visual onset events at random times. Across seven experiments, the visual onsets tested size, spatial frequency, contrast, orientation, motion direction, and motion speed dependencies of saccadic inhibition. We also investigated how inhibition might depend on the behavioral relevance of the appearing stimuli. We found that saccadic inhibition starts earlier, and is stronger, for large stimuli of low spatial frequencies and high contrasts. Moreover, saccadic inhibition timing depends on motion direction and orientation, with earlier inhibition systematically occurring for horizontally drifting vertical gratings. On the other hand, saccadic inhibition is stronger for faster motions and when the appearing stimuli are subsequently foveated. Besides documenting a range of feature tuning dimensions of saccadic inhibition to the properties of exogenous visual stimuli, our results establish macaque monkeys as an ideal model system for unraveling the neural mechanisms underlying a ubiquitous oculomotor phenomenon in visual neuroscience.NEW & NOTEWORTHY Visual onsets dramatically reduce saccade generation likelihood with very short latencies. Such latencies suggest that stimulus-induced visual responses, normally jump-starting perceptual and scene analysis processes, can also directly impact the decision of whether to generate saccades or not, causing saccadic inhibition. Consistent with this, we found that changing the appearance of the visual onsets systematically alters the properties of saccadic inhibition. These results constrain neurally inspired models of coordination between saccade generation and exogenous sensory stimulation.


Assuntos
Movimentos Oculares , Movimentos Sacádicos , Animais , Movimento (Física) , Macaca mulatta , Inibição Psicológica , Tempo de Reação/fisiologia , Estimulação Luminosa
5.
Reprod Domest Anim ; 56(2): 270-277, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32920908

RESUMO

Separation of X and Y chromosome-bearing sperm is an appropriate method for the selection of desired sex of offspring to increase the profit in livestock industries. The purpose of this study was the production of a monoclonal antibody against recombinant bovine sex-determining region Y protein for separation Y sperm. The hybridoma cells from splenocytes of immunized female's balb/C mice and Sp2/0 cells were made. The binding affinity of our monoclonal antibody (mAbSRY2) was compared with mouse monoclonal SRY-15. The Western blot method indicated that mAbSRY2 successfully detected the rbSRY protein. The specificity and sensitivity of mAbSRY2 is comparable to SRY-15 commercially ones. The SRY gene in 100% of bull semen contains the Y chromosome that had the strongest binding affinity to mAbSRY2 was synthesized. In other words, the binding affinity of semen contains the X sperms near the negative control. In general, this immunological method can help to separate X from Y sperms. However, the mAbSRY2 is bind to Y-bearing sexed sperm, but in the future; the sexed sperms need to apply in farms.


Assuntos
Genes sry/imunologia , Pré-Seleção do Sexo/veterinária , Espermatozoides/imunologia , Animais , Anticorpos Monoclonais/farmacologia , Bovinos , Feminino , Hibridomas , Masculino , Camundongos Endogâmicos BALB C , Pré-Seleção do Sexo/métodos , Baço , Cromossomo Y/imunologia
6.
J Neurophysiol ; 123(6): 2136-2153, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32347160

RESUMO

The primate superior colliculus (SC) is causally involved in microsaccade generation. Moreover, visually responsive SC neurons across this structure's topographic map, even at peripheral eccentricities much larger than the tiny microsaccade amplitudes, exhibit significant modulations of evoked response sensitivity when stimuli appear perimicrosaccadically. However, during natural viewing, visual stimuli are normally stably present in the environment and are only shifted on the retina by eye movements. Here we investigated this scenario for the case of microsaccades, asking whether and how SC neurons respond to microsaccade-induced image jitter. We recorded neural activity from two male rhesus macaque monkeys. Within the response field (RF) of a neuron, there was a stable stimulus consisting of a grating of one of three possible spatial frequencies. The grating was stable on the display, but microsaccades periodically jittered the retinotopic RF location over it. We observed clear short-latency visual reafferent responses after microsaccades. These responses were weaker, but earlier (relative to new fixation onset after microsaccade end), than responses to sudden stimulus onsets without microsaccades. The reafferent responses clearly depended on microsaccade amplitude as well as microsaccade direction relative to grating orientation. Our results indicate that one way for microsaccades to influence vision is through modulating how the spatio-temporal landscape of SC visual neural activity represents stable stimuli in the environment. Such representation depends on the specific pattern of temporal luminance modulations expected from the relative relationship between eye movement vector (size and direction) on one hand and spatial visual pattern layout on the other.NEW & NOTEWORTHY Despite being diminutive, microsaccades still jitter retinal images. We investigated how such jitter affects superior colliculus (SC) activity. We found that SC neurons exhibit short-latency visual reafferent bursts after microsaccades. These bursts reflect not only the spatial luminance profiles of visual patterns but also how such profiles are shifted by eye movement size and direction. These results indicate that the SC continuously represents visual patterns, even as they are jittered by the smallest possible saccades.


Assuntos
Fixação Ocular/fisiologia , Neurônios/fisiologia , Movimentos Sacádicos/fisiologia , Colículos Superiores/fisiologia , Percepção Visual/fisiologia , Animais , Fenômenos Eletrofisiológicos , Macaca mulatta , Masculino
7.
Cereb Cortex ; 28(4): 1502-1515, 2018 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-29415124

RESUMO

Rhythmic synchronization of neurons is known to affect neuronal interactions. In the motor system, oscillatory power fluctuations modulate corticospinal excitability. However, previous research addressing phase-specific gain modulation in the motor system has resulted in contradictory findings. It remains unclear how many time windows of increased responsiveness each oscillatory cycle provides. Moreover, we still lack conclusive evidence as to whether the motor cortex entails an intrinsic response modulation along the rhythm cycle, as shown for spinal neurons. We investigated this question with single-pulse transcranial magnetic stimulation over the primary motor cortex at rest. Application of near-motor threshold stimuli revealed a frequency- and phase-specific gain modulation at both cortical and spinal level, independent of the spontaneous oscillatory power fluctuations at each level. We detected bilateral sensorimotor circuits in the lower beta-band (14-17 Hz) and unilateral corticospinal circuits in the upper beta-band (20-24 Hz). These findings provide novel evidence that intrinsic activity in the human motor cortex modulates input gain along the beta oscillatory cycle within distinct circuits. In accordance with periodic alternations of synchronous hyper- and depolarization, increased neuronal responsiveness occurred once per oscillatory beta cycle. This information may lead to new brain state-dependent and circuit-specific interventions for targeted neuromodulation.


Assuntos
Ritmo beta/fisiologia , Potencial Evocado Motor/fisiologia , Músculo Esquelético/fisiologia , Tratos Piramidais/fisiologia , Adolescente , Adulto , Análise por Conglomerados , Eletroencefalografia , Eletromiografia , Feminino , Antebraço/inervação , Voluntários Saudáveis , Humanos , Masculino , Estimulação Magnética Transcraniana , Adulto Jovem
8.
Int J Toxicol ; 38(3): 202-208, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31113282

RESUMO

Nicotine is a major component of tobacco plants and is responsible for the development of reproductive problems in smokers. Nicotine has been recognized to result in oxidative stress by inducing the generation of reactive oxygen species (ROS) in some parts of female reproductive system, but the effect of nicotine on endometrium that plays an important role in reproductive biology stays unexplored. The aim of this work was to clarify the direct effects of nicotine administration on the antioxidant defense system and lipid peroxidation in human endometrial cells. Human endometrial stromal primary cells were treated with nicotine (0, 10-11, 10-8, and 10-6 M) for 24 hours. On nicotine administration, the endometrial cells were associated with a decrease in antioxidant defense markers such as Glutathione (GSH) level, glutathione peroxidase (GPx), glutathione reductase (GR), and catalase (CAT) enzymes activity and higher levels of malondialdehyde (MDA) in a dose-dependent manner when compared to the control. We concluded that nicotine as a pro-oxidant affects the oxidative state of the endometrial cells.


Assuntos
Endométrio/citologia , Nicotina/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Adulto , Catalase/metabolismo , Células Cultivadas , Relação Dose-Resposta a Droga , Feminino , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Redutase/metabolismo , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Malondialdeído/metabolismo , Adulto Jovem
10.
Nutr Cancer ; 70(5): 770-775, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29781726

RESUMO

Some types of cancers show a strong relationship with diabetes and play a central role in mortality in the patient population suffering from diabetes mellitus. In this study, HepG2 cells have been used to investigate the toxic effects of hyperglycemia and/or quercetin (Q) on mammalian target of rapamycin (m-TOR) and nuclear factor erythroid 2-related factor 2 (Nrf-2) expression as central molecules involved in cancer. HepG2 cells were cultured with different concentrations of glucose (5.5, 30, and 50 mM) and/or Q (25 µM) for 48 and 72 h. Effects of glucose and/or Q on m-TOR and Nrf-2 expression were assayed by quantitative real-time PCR (qRT-PCR). qRT-PCR results revealed that 30 and 50 mM of glucose increased m-TOR expression at 48 h, although after 72 h, only 30 mM had an increasing effect. At 50 mM, glucose-induced Nrf-2 gene expression after both 48 and 72 h. The results also showed that 25 µM of Q reduced m-TOR and Nrf-2 expression at both 30 and 50 mM after 48 and 72 h incubation. Q has potential effects on reducing oxidative stress caused by hyperglycemia and during diabetes may be able to modulate some carcinogenic signaling pathways.


Assuntos
Glucose/farmacologia , Fator 2 Relacionado a NF-E2/genética , Quercetina/farmacologia , Serina-Treonina Quinases TOR/genética , Relação Dose-Resposta a Droga , Regulação da Expressão Gênica/efeitos dos fármacos , Glucose/administração & dosagem , Células Hep G2 , Humanos , Hiperglicemia/metabolismo , Quercetina/administração & dosagem
11.
Toxicol Mech Methods ; 26(8): 595-600, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27552315

RESUMO

Cigarette smoke is a complex mixture of toxic chemicals, including nicotine, carbon monoxide, and several recognized carcinogens and mutagens. Nicotine has a direct disturbing influence on steroid hormones (estrogen and progesterone), which are essential components of the female reproductive system, but the effect of nicotine on the hormone receptors is not yet clear. The aim of this study was to elucidate the effect of nicotine on the expression of estrogen receptor (ER), progesterone receptor (PR), and vascular endothelial growth factor (VEGF) in endometrial stromal cells. Expression levels of PR, ER, and VEGF in human endometrial stromal primary cells treated with nicotine (0, 10-11, 10-8, and 10-6 µM) for 24 h were measured by quantitative real-time PCR. MTT assay demonstrated that nicotine decreased cell viability in a dose-dependent manner. Real-time PCR data showed that despite decrease in ER expression in the nicotine-treated groups compared with the control, nicotine exerted an increased inhibitory effect on PR expression compared to that on ER expression. VEGF mRNA expression in nicotine-treated endometrial stromal cells was increased. The results from this study provide novel evidence for inhibitory effects of nicotine on steroid hormones receptor expression in human primary endometrial cells. Also, our data suggest that nicotine might have angiogenesis effects on these cells.


Assuntos
Endométrio/efeitos dos fármacos , Receptor alfa de Estrogênio/genética , Expressão Gênica/efeitos dos fármacos , Nicotina/toxicidade , Receptores de Progesterona/genética , Fator A de Crescimento do Endotélio Vascular/genética , Adulto , Técnicas de Cultura de Células , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Endométrio/citologia , Endométrio/metabolismo , Feminino , Humanos , Reação em Cadeia da Polimerase em Tempo Real , Células Estromais/efeitos dos fármacos , Células Estromais/metabolismo , Adulto Jovem
12.
Toxicol Mech Methods ; 25(2): 98-104, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25418342

RESUMO

BACKGROUND AND OBJECTIVE: Cyclosporine A (CsA) is an immunosuppressive agent administered to transplant patients. A well-known reported oral side effect of CsA consumption is gingival overgrowth (GO). Changes in the expression of integrins occurring in the gingiva following CsA treatment have been reported but these reports are mainly concerned with the connective tissue of the gingiva. In this study we targeted the alterations in the oral epithelium using KB cells, an oral epithelial cell line. METHODS: Cultured oral epithelial cells were treated with increasing concentrations of CsA (0.1, 1 and 10 µg/mL) and the molecular changes involving antioxidant enzymes [glutathione peroxidase (GPx) and glutathione reductase (GR)] and the level of reactive oxygen species (ROS) were measured. Quantitative real-time PCR was used to assess the expression of selected integrins (α2, α5 and ß1). RESULTS: At CsA concentration above 0.1 µg/mL GPx demonstrated an increase in activity while GR activity and the level of reduced glutathione were diminished (p < 0.05). α5 and ß1 integrin were downregulated at all treatment concentrations of CsA while α2 integrin presented this effect at concentrations above 1 µg/mL (p < 0.05). CONCLUSION: The results suggest a possible role for oxidative stress and the altered expression of integrins in the pathology of CsA-induced gingival overgrowth.


Assuntos
Ciclosporina/toxicidade , Células Epiteliais/efeitos dos fármacos , Crescimento Excessivo da Gengiva/induzido quimicamente , Imunossupressores/toxicidade , Integrinas/metabolismo , Mucosa Bucal/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Linhagem Celular , Relação Dose-Resposta a Droga , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Crescimento Excessivo da Gengiva/metabolismo , Crescimento Excessivo da Gengiva/patologia , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Redutase/metabolismo , Humanos , Integrina alfa2/metabolismo , Integrina alfa5/metabolismo , Integrina beta1/metabolismo , Integrinas/genética , Mucosa Bucal/metabolismo , Mucosa Bucal/patologia , Espécies Reativas de Oxigênio/metabolismo
13.
Toxicol Mech Methods ; 24(6): 412-6, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24845846

RESUMO

OBJECTIVES: Propranolol, a beta-adrenergic blocker, is used in the treatment of a large number of cardiovascular diseases such as hypertension and arrhythmias. Propranolol, in combination with furosemide, is used to treat hypertensive disorders although their side effect profile is not very obvious. In present study, the effects of the drugs furosemide and propranolol were in corporately investigated both on glutathione homeostasis and their antioxidant effect on ACHN cells. METHODS: The cytoxicities and antioxidant effects of these two clinically important drugs on human kidney cell lines were evaluated using MTT following by the determination of glutathione reductase (GR) and glutathione peroxidase (GPx) activities and measuring the level of reduced glutathione (GSH). RESULTS: Propranolol induced a significant cytotoxic effect at 100 µM, while furosemide was cytotoxic at doses of 250 and 1000 µg/ml. A slight increase in GPx and GR activities and GSH level was observed with propranolol and furosemide treatment alone, while the two drugs together caused a significant increase in GPx and GR activities (35% and 42%, respectively) and GSH content (35%) in ACHN cell lysates (p < 0.05). CONCLUSIONS: Our results demonstrate that although high doses of furosemide and propranolol are cytotoxic, co-administration of low doses may improve the antioxidant defense in patients undergoing treatment with these two important drugs.


Assuntos
Furosemida/toxicidade , Glutationa/metabolismo , Homeostase/efeitos dos fármacos , Rim/citologia , Rim/efeitos dos fármacos , Propranolol/toxicidade , Antagonistas Adrenérgicos beta/administração & dosagem , Antagonistas Adrenérgicos beta/toxicidade , Linhagem Celular , Diuréticos/administração & dosagem , Diuréticos/toxicidade , Quimioterapia Combinada , Fibroblastos/efeitos dos fármacos , Furosemida/administração & dosagem , Furosemida/química , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Glutationa Peroxidase/genética , Glutationa Peroxidase/metabolismo , Glutationa Redutase/genética , Glutationa Redutase/metabolismo , Humanos , Estrutura Molecular , Propranolol/administração & dosagem , Propranolol/química
14.
BMC Res Notes ; 17(1): 316, 2024 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-39428497

RESUMO

OBJECTIVE: The objective of the present study was to examine the effect of calorie restricted diet (CRD) plus inulin supplementation on serum levels of tryptophan (Trp), kynurenine (Kyn) and Trp/Kyn ratio in obese women with major depressive disorder (MDD). RESULTS: In this double-blind placebo-controlled randomized clinical trial, 51 obese women (BMI = 30-40 kg/m2) with mild MDD were assessed for depression level using Hamilton depression rating scale (HDRS). The patients were randomly allocated into either "Prebiotic group" (received 10 g/day inulin) or "Placebo group" (received 10 g/day maltodextrin). All participants also received individualized CRD. Fasting serum levels of Trp, Kyn, and Trp/Kyn ratio were assessed at baseline and after 8 weeks. Results showed slightly greater increases in serum levels of Trp and Trp/Kyn ratio as well as reductions in serum level of Kyn and HDRS score in prebiotic group than placebo group. However, between group differences in these parameters as well as HDRS score were not statistically significant after adjusting for baseline variables at the end of the trial. Results indicates that CRD accompanied by inulin supplementation (10 g/day) did not influence serum levels of Trp, Kyn and Trp/Kyn ratio as well as HDRS score after 8 weeks. TRIAL REGISTRATION: The trial was registered in the Iranian registry of clinical trials at 2018-08-02 ( https://www.irct.ir/ ; registration number: IRCT20100209003320N15).


Assuntos
Transtorno Depressivo Maior , Suplementos Nutricionais , Cinurenina , Obesidade , Prebióticos , Triptofano , Humanos , Feminino , Transtorno Depressivo Maior/sangue , Transtorno Depressivo Maior/dietoterapia , Transtorno Depressivo Maior/tratamento farmacológico , Transtorno Depressivo Maior/terapia , Triptofano/sangue , Método Duplo-Cego , Cinurenina/sangue , Adulto , Prebióticos/administração & dosagem , Obesidade/sangue , Obesidade/dietoterapia , Obesidade/complicações , Obesidade/terapia , Pessoa de Meia-Idade , Inulina/administração & dosagem , Restrição Calórica/métodos
15.
Inform Med Unlocked ; 36: 101147, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36510496

RESUMO

Vaccines are undoubtedly the most effective means of combating viral diseases like COVID-19. However, there are risks associated with vaccination, such as incomplete viral deactivation or potential adverse effects in humans. However, designing and developing a panel of new drug molecules is always encouraged. In an emergency, drug repurposing research is one of the most potent and rapid options. RdRp (RNA-dependent RNA polymerase) has been discovered to play a pivotal role in viral replication. In this study, FDA-approved drugs bexarotene, diiodohydroxyquinoline, abiraterone, cetilistat, and remdesivir were repurposed against the RdRp by molecular modeling, docking, and dynamic simulation. Furthermore, to validate the potency of these drugs, we compared them to the antiviral remdesivir, which inhibits RdRp. Our finding indicated that the selected drugs have a high potential to be developed as RdRp inhibitors and, with further validation studies, could serve as potential drugs for the treatment of COVID-19.

16.
J Biomed Phys Eng ; 13(1): 99-104, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36818008

RESUMO

Background: Breast hypertrophy is a significant health problem with both physiological and psychological impacts on the patients' lives. Patients with macromastia adopt a corrective posture due to the effect of the breast on the center of gravity and possibly in a subconscious effort to conceal their breasts. Objective: This study aimed to evaluate whether the posture of patients with macromastia changed after the reduction of mammoplasty. Material and Methods: In this prospective study, patients with breast cup sizes C, D, and DD were scheduled for reduction mammoplasty in 3 Shiraz University Hospitals. Age, weight, height, and preoperative cup sizes of the breasts were recorded for every patient, and all patients underwent posture analysis with forceplate before and after reduction mammoplasty. Finally, the preoperative and postoperative data were compared. Results: Mean age at the time of reduction mammaplasty was 43.57±9.1; the mean pre-operation, such as weight, height, and mean the body mass index (BMI) was 76.57±10 kg, 158.28±6 cm and 30.57±4.1, respectively. The average Anterior-posterior (AP) direction velocity before and after the surgery was 0.85±0.12 cm/s and 0.79±0.098, respectively. These values were 0.83±0.09 and 0.81±0.10 for the mediolateral direction. The Detrended Fluctuation Analysis (DFA) value for the AP direction was 1.63±0.3 and 1.60±0.2 for pre-and post-surgery, respectively, which was not statistically different. The DFA value for maximum likelihood (ML) direction was 1.65±0.2 and 1.48±0.2 in pre-op and post-op, respectively, which was statistically significantly different. Conclusion: Reducing the weight of enlarged breasts can correct disturbed sagittal balance and postural sway.

17.
Asian Pac J Cancer Prev ; 24(8): 2765-2772, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37642063

RESUMO

BACKGROUND: Natural treatment of cancer has received a lot of attention recently due to its advantages including low cost, and fewer side effects. In this study, we aimed to investigate the antimetastatic properties of Cyrtopodion scabrum, a common home gecko, through Epithelial-Mesenchymal Transition (EMT) process. METHODS: Human colon cancer HCT116 cell line was selected and allocated into the following experimental groups: untreated control, vehicle control (DMSO), Retinoic acid (RA), and two treatment groups including aqueous C.scabrum Whole Extract (CWE) and C.scabrum Cell Extract (CCE) groups. The effects of the two different extracts on the viability, migration, and morphology of HCT116 cells were investigated using MTT, colony formation, and wound healing assay as well as microscopic evaluation. We also investigated the gene expression of E-cad, N-cad, and Snail genes using Real-Time PCR analysis. RESULTS: Our findings revealed that CWE and CCE were toxic to the HCT116 cell line with IC50 values of 590 and 680 µg/mL, respectively. Colony formation and migration ability of cancer cells were also inhibited by the two extracts, and the morphology of the cells were determined as epithelial phenotype. Moreover, the expression of N-cad and Snail were remarkably decreased in CWE and CCE, and RA groups, while E-cad didn't change significantly as compared to the control. CONCLUSION: The results suggest that C. scabrum extract (CsE) may induce its anti-cancer activity through the inhibition of cancer cell growth and the EMT process. CCE, as a valuable natural source, could be also suggested, to be used as an alternative/complementary medicine for the treatment of cancer, in clinical trials.


Assuntos
Neoplasias do Colo , Lagartos , Humanos , Animais , Transição Epitelial-Mesenquimal , Projetos de Pesquisa , Células HCT116
18.
BMC Psychol ; 11(1): 211, 2023 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-37474960

RESUMO

INTRODUCTION: This study aimed to translate and assess the psychometric properties of the Persian version of the "Safety Attitude Questionnaire" in the NICUs. METHODS: In this psychometric study, the "Safety Attitude Questionnaire" was translated into Persian. Then this version was used for psychometric evaluation. For this purpose, the qualitative face, content validity and construct validity were performed by confirmatory factor analysis. Internal consistency and stability reliability were calculated. Data were analyzed using SPSS and AMOS software. RESULTS: Face validity was also performed with a slight change in four items. The factor structure of the tool was determined by confirmatory factor analysis. Fit indices were appropriate. Internal consistency reliability in the whole questionnaire was 0.65 and the stability reliability was calculated to be 0.64. DISCUSSION AND CONCLUSION: "Safety Attitude Questionnaire" has appropriate psychometric properties and can be used in NICUs.


Assuntos
Atitude do Pessoal de Saúde , Tradução , Humanos , Psicometria , Reprodutibilidade dos Testes , Inquéritos e Questionários
19.
Front Public Health ; 11: 989458, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36778543

RESUMO

Background: Providing nursing care to patients with COVID-19 has put additional pressure on nurses, making it challenging to meet several care requirements. This situation has caused parts of nursing care to be missed, potentially reducing the quality of nursing care and threatening patient safety. Therefore, the present study aimed at explaining the factors forming missed nursing care during the COVID-19 pandemic from the perspective of nurses. Methods: This qualitative study was conducted using a conventional content analysis approach in Iran, 2020-2021. Data were collected from in-depth, semi-structured interviews with 14 nurses based on purposive sampling. Data analysis was performed simultaneously with data collection. Graneheim and Lundman's approach was used for data analysis, and MAXQDA software was used for data management. After transcribing the recorded interviews, to achieve the accuracy and validity of the study, the criteria proposed by Lincoln and Guba were considered and used. Results: A total of 14 nurses with a mean age and standard deviation of 31.85 ± 4.95 and working in the COVID-19 wards participated in the study. The acquired data were categorized into four main categories: care-related factors, disease-related factors, patient-related factors, and organization-related factors. The category "care-related factors" comprised uncertainty in care, PPE-related limitations, attrition from care, and futile care. The category "disease-related factors" consisted of the extension of symptoms, unpredictable peaks of the disease, and restriction on the presence of patients' companions. The category "patient-related factors" included comorbidities, elderly patients, and deterioration of infected patients. Ultimately, the category "organization-related factors" consisted of restrictions on equipment supply, lack of human resources, weaknesses in teamwork, and an unsupportive work environment. Conclusion: The results of this study showed that several reasons including factors related to care, patient, disease, and organization cause missed nursing care. By modifying the related affecting factors and considering the effective mechanisms to minimize missed nursing care, it is possible to provide better services.


Assuntos
COVID-19 , Idoso , Humanos , COVID-19/epidemiologia , Pandemias , Pesquisa Qualitativa , Análise de Dados , Gerenciamento de Dados
20.
Asian Pac J Cancer Prev ; 24(4): 1209-1216, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37116142

RESUMO

BACKGROUND: The use of complementary and/or alternative medicine to increase the efficacy and decrease the side effects of current cancer treatment is highly required. In this in-vivo study, we aimed to investigate the anti-tumor activity and probable side effects of a natural treatment, Cyrtopodion scabrum extract (CsE), in a model of tumor bearing mice. METHODS: We established 28 female CT26-tumor bearing balb/c-mice model. We divided them randomly into four groups (n=7): Negative control received distilled water (DW) and the three treatment groups were administered with 5-FU and two different doses (300 and 600 mg/kg) of the gecko aqueous extract, respectively. The changes in the tumor volumes and weights during and after treatment, along with the blood cell counts; spleen and thymus indices were assessed in the treatment groups. We have also measured the serum TNF-α, VEGF, AST, ALT and GSH, as well as the physical activities of the experimental mice. RESULTS: We found that the means of tumor weights and volumes in both CsE and 5-FU treated groups were significantly lower than the untreated group (p<0.05). Serum TNF-α and VEGF levels in both CsE treated groups were remarkably lower than 5-FU and untreated groups (p<0.05). The 5-FU treatment caused a remarkably decrease in serum GSH, RBC count, WBC count, thymus index, and spleen index , while CsE treatment maintained these quantities, with no significant changes, compared to the control group. AST and ALT were not significantly changed in none of the treated groups compared to control. CONCLUSION: Altogether, data suggest C. scabrum, as an effective and safe anti-cancer natural source, which could be used as an alternative/complementary medicine for the treatment of patients who suffer from colon cancer.


Assuntos
Neoplasias do Colo , Lagartos , Feminino , Camundongos , Animais , Fluoruracila/farmacologia , Fluoruracila/uso terapêutico , Fator A de Crescimento do Endotélio Vascular , Fator de Necrose Tumoral alfa , Neoplasias do Colo/tratamento farmacológico , Anti-Inflamatórios , Camundongos Endogâmicos BALB C
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