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1.
Psychiatr Hung ; 38(3): 218-231, 2023.
Artigo em Húngaro | MEDLINE | ID: mdl-37982269

RESUMO

BACKGROUND: In this study, we examined psychiatric teams in a Hungarian sample before the COVID-19 pandemic. The aim of our research is to examine Hungarian psychiatric teams along different workplace psychosocial factors (collaboration management, organization and job, workplace requirements, work-life balance, trust, health and well-being) in order to assess them in terms of hierarchy and competence. Moreover we examine the mental and somatic effects of these factors. METHODS: We conducted a cross-sectional survey of Hungarian mental health care workers (N =79). The main question of the study was how perceived hierarchy and competence boundary violations are associated to psychosocial factors of the COPSOQ-II questionnaire (Copenhagen Psychosocial Questionnaire II) in general, and among employees in different job groups. RESULTS: Based on bootstrapped binary logistic regression performed on the full sample, we found that perceived hierarchy is associated with control, social support of co-workers and stress, while violation of competence boundaries is associated with job recognition, job clarity and fairness. DISCUSSION: Our results show that where mental health care workers experienced less perceived hierarchy within the team, they were more likely to feel that they had control over their work. Furthermore, in hierarchies perceived as superior-subordinate relations, the quality of the relationships within the team seems to be much more important. CONCLUSIONS: This research can be the starting point for a comprehensive study of other psychiatric teams with the aid of a widely used measure, providing an opportunity for comparison with other health teams at an international level.


Assuntos
COVID-19 , Pandemias , Humanos , Hungria , Estudos Transversais , Emoções , COVID-19/epidemiologia
2.
Int J Mol Sci ; 23(19)2022 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-36232575

RESUMO

In recent years, several studies aimed to investigate the metabolic effects of non-functioning or absent cyclophilin D (CypD), a crucial regulatory component of mitochondrial permeability transition pores. It has been reported that the lack of CypD affects glucose and lipid metabolism. However, the findings are controversial regarding the metabolic pathways involved, and most reports describe the effect of a high-fat diet on metabolism. We performed a lipidomic analysis of plasma and liver samples of CypD-/- and wild-type (WT) mice to reveal the lipid-specific alterations resulting from the absence of CypD. In the CypD-/- mice compared to the WT animals, we found a significant change in 52% and 47% of the measured 225 and 201 lipid species in liver and plasma samples, respectively. The higher total lipid content detected in these tissues was not accompanied by abdominal fat accumulation assessed by nuclear magnetic resonance imaging. We also documented characteristic changes in the lipid composition of the liver and plasma as a result of CypD ablation with the relative increase in polyunsaturated membrane lipid species. In addition, we did not observe remarkable differences in the lipid distribution of hepatocytes using histochemistry, but we found characteristic changes in the hepatocyte ultrastructure in CypD-/- animals using electron microscopy. Our results highlight the possible long-term effects of CypD inhibition as a novel therapeutic consideration for various diseases.


Assuntos
Lipidômica , Proteínas de Transporte da Membrana Mitocondrial , Animais , Peptidil-Prolil Isomerase F , Ciclofilinas/genética , Ciclofilinas/metabolismo , Glucose , Fígado/metabolismo , Lipídeos de Membrana , Camundongos , Camundongos Knockout , Proteínas de Transporte da Membrana Mitocondrial/metabolismo
3.
Arch Orthop Trauma Surg ; 142(1): 25-31, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32844306

RESUMO

To date two main techniques are used in arthroscopic full-thickness rotator cuff tears, the conventional knot-tying suture bridge technique and the knotless technique. We evaluated whether there is a difference in clinical outcome using both techniques. Our patients underwent arthroscopic treatment of full-thickness rotator cuff tears, and we retrospectively evaluated clinical function, strength and surgery time. Eighty-three shoulders operated between September 2012 and December 2013 were included in the study. We had nineteen patients in the knotless group, and sixty-four in the knot-tying group. In addition, we performed preoperatively radiological (magnetic resonance imaging-MRI) conformation of full-thickness rotator cuff tear in our patients. For clinical evaluation, we used Quick Disabilities of the Arm, Shoulder and Hand score (q-DASH) and the Shoulder Pain and Disability (SPADI) score, and we measured the strength of a range of motion postoperatively using a conventional dynamometer. The patients were evaluated preoperatively, and at 6, 9, and 12 months postoperatively. The follow-up period was 12 months. The scores in both treatment groups improved at twelve months follow-up, but there was no statistical difference between both groups at twelve months after surgery; q-DASH score between groups (p = 0.092) and SPADI score (p = 0.700). Similarly, there was no statistical difference between the groups in regard to strength, surgery time, and range of motion at the twelve months follow-up. Our data confirm that both techniques may be used successfully to repair full-thickness rotator cuff tears with very good functional outcome.Level of evidence IV.


Assuntos
Lesões do Manguito Rotador , Manguito Rotador , Artroscopia , Humanos , Imageamento por Ressonância Magnética , Estudos Retrospectivos , Manguito Rotador/diagnóstico por imagem , Manguito Rotador/cirurgia , Lesões do Manguito Rotador/diagnóstico por imagem , Lesões do Manguito Rotador/cirurgia , Técnicas de Sutura , Resultado do Tratamento
4.
J Chem Inf Model ; 59(5): 1957-1964, 2019 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-30742770

RESUMO

Accurate hydrogen placement in molecular modeling is crucial for studying the interactions and dynamics of biomolecular systems. The carboxyl functional group is a prototypical example of a functional group that requires protonation during structure preparation. To our knowledge, when in their neutral form, carboxylic acids are typically protonated in the syn conformation by default in classical molecular modeling packages, with no consideration of alternative conformations, though we are not aware of any careful examination of this topic. Here, we investigate the general belief that carboxylic acids should always be protonated in the syn conformation. We calculate and compare the relative energetic stabilities of syn and anti acetic acid using ab initio quantum mechanical calculations and atomistic molecular dynamics simulations. We focus on the carboxyl torsional potential and configurations of microhydrated acetic acid from molecular dynamics simulations, probing the effects of solvent, force field (GAFF vs GAFF2), and partial charge assignment of acetic acid. We show that while the syn conformation is the preferred state, the anti state may in some cases also be present under normal NPT conditions in solution.


Assuntos
Acetatos/química , Ácidos Carboxílicos/química , Simulação de Dinâmica Molecular , Teoria Quântica , Conformação Molecular
5.
Pediatr Transplant ; 23(6): e13529, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31259462

RESUMO

Sleep-disordered breathing, a prevalent condition among adult renal transplant (RTx) recipients, has become an established independent risk factor of MetS, and furthermore, it might contribute to increased CV risk. Despite the proven correlations in adults, there is a lack of evidence for its significance in the pediatric RTx population. In this study, we aimed at assessing the prevalence and the clinical correlates of SDB in RTx children. Data of 13 patients (age [mean ± SD]: 14.2 ± 2.7 years) were analyzed. SDB was evaluated by PSG, as severity score OAHI was applied. Carbohydrate metabolism was characterized by OGTT, whereas CV status was studied by ABPM. Three composite end-points were calculated as sum of z-scores: daytime systolic and diastolic BP; nighttime systolic and diastolic BP; and glucose and insulin levels at 120 minutes. Eight patients (61.5%) were diagnosed with SDB of whom five patients (38.5%) had moderate or severe SDB. In linear regression analysis, OAHI during REM was associated with the CV variables (daytime BP P = 0.032, ß = 0.748; nighttime BP P = 0.041, ß = 0.715), and the correlations remained significant after adjustments for BMI. However, we did not confirm a significant association with the metabolic variables. The prevalence of SDB was high, and its severity during REM was a predictor of the BP suggesting that RTx children with SDB might be at risk of developing CV complications, especially HTN similarly to adults.


Assuntos
Falência Renal Crônica/complicações , Falência Renal Crônica/cirurgia , Transplante de Rim , Síndromes da Apneia do Sono/complicações , Adolescente , Antropometria , Glicemia/análise , Pressão Sanguínea , Carboidratos/química , Criança , Estudos Transversais , Diástole , Feminino , Teste de Tolerância a Glucose , Humanos , Insulina/sangue , Modelos Lineares , Masculino , Polissonografia , Prevalência , Fatores de Risco , Sístole , Transplantados
6.
AAPS PharmSciTech ; 20(2): 90, 2019 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-30684094

RESUMO

Celecoxib (Celebrex®) is the only widely used NSAID that selectively inhibits the COX-2 isoenzyme. Celebrex® is absorbed slowly in the fasted state and food intake further delays absorption. In this work, an amorphous water dispersible granule formulation of celecoxib is described with in vitro characterization, preclinical and clinical data. The formulation exhibited very high passive permeability and apparent solubility, significantly outperforming the micronized celecoxib and the drug product Celebrex®. The granule formulation remained stable for at least 1 year in stability tests. In dog studies, tmax was 1 h with over 50% of Cmax reached within 15 min regardless of food intake. A phase 1 clinical trial was conducted with 12 volunteers at 100- and 200-mg doses. Celecoxib plasma concentrations reached 250 ng/ml, the effective therapeutic plasma level, in less than 15 min regardless of food or dose. The novel celecoxib formulation is rapidly absorbed, demonstrating the potential utility as an acute treatment offering advantages over the currently marketed product.


Assuntos
Anti-Inflamatórios não Esteroides/química , Celecoxib/química , Adolescente , Adulto , Idoso , Anti-Inflamatórios não Esteroides/farmacocinética , Celecoxib/farmacocinética , Composição de Medicamentos , Estabilidade de Medicamentos , Humanos , Masculino , Pessoa de Meia-Idade , Permeabilidade , Solubilidade , Adulto Jovem
7.
Acta Vet Hung ; 67(1): 115-126, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30922099

RESUMO

The aim of this study was to examine the effect of twin pregnancy, fetal laterality, the number of corpora lutea (CL) and cavitary CL on pregnancy losses in Holstein-Friesian cows with a positive pregnancy diagnosis based on ultrasonography between days 29-42 after AI. Pregnancy was confirmed by transrectal palpation between days 57-70 after AI and at the time of drying-off as well. Twin pregnancy rate was 8.4% at the time of the early pregnancy examination. Pregnancy loss did not differ between singleton- and twin-carrying animals either between days 57-70 of gestation or at drying-off. More losses occurred in singletons between days 29-42 and 57-70 in cows with cavitary than in cows with noncavitary CL (12.1% vs. 3.6%; P < 0.05) and in cows with double CL than in cows with single CL (7.3% vs. 3.6% %; P < 0.05). Between days 57-70 of gestation and drying-off this difference was still significant (20.7% vs. 3.7%; P < 0.001), while it was non-significant between cows with one CL (5.7%) vs. double CL (3.7%). Cavity occurrence was not affected by hormone therapy prior to AI (either PGF2α or OvSynch; 4.4% vs. 5.4%, respectively); however, the number of CL was reduced by the treatments (11.6 vs. 19.6%; P < 0.0005). In twin pregnancies there was no difference in the pregnancy losses between bilateral and unilateral pregnancies at any time point. The length of gestation was 278.2 ± 10.5 (singleton) and 267.4 ± 31.2 (twin) days, respectively (P < 0.01). The stillbirth ratio was higher in twin carriers than in singleton carriers (19.5% vs. 5.3%; P < 0.001).


Assuntos
Doenças dos Bovinos , Prenhez , Gravidez Múltipla , Natimorto/veterinária , Animais , Bovinos , Corpo Lúteo , Feminino , Modelos Logísticos , Gravidez , Fatores de Risco
8.
Acta Vet Hung ; 67(2): 274-281, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31238726

RESUMO

The aim of this study was to create a fetal heart rate (FHR) reference curve for singleton bovine fetuses in the first trimester of gestation and to determine its possible relationship with the outcome of pregnancy. Forty-eight Holstein-Friesian cows with one fetus and five cows with twins were used. Fetal heart beatings were recorded on videotape during transrectal scanning with a 5 and/or 7.5 MHz linear array transducer on a weekly basis between Days 40 and 95 of gestation. FHR was calculated by averaging the results of five counts of the same record by the same observer. For singleton pregnancies, a reference curve was created using the mean, the standard deviation (SD) and the 5th and 95th percentiles. The FHR increased from Days 40-46 (173 beats/min) to Days 61-67 (183 beats/min). After a peak, the FHR decreased slowly until Days 89-95 (175 beats/min), while the SD increased. There was no significant difference between singleton and twin fetuses. in the aborted and lost fetuses in twin gestation due to fetal reduction, both bradycardia and tachycardia were detected compared to the singleton pregnancy reference curve.


Assuntos
Frequência Cardíaca Fetal , Prenhez/fisiologia , Animais , Bovinos , Feminino , Gravidez , Valores de Referência , Ultrassom Focalizado Transretal de Alta Intensidade/veterinária , Gravação de Videoteipe
9.
Acta Vet Hung ; 67(2): 241-245, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31238723

RESUMO

Activities of alkaline phosphatase, aspartate aminotransferase and alanine aminotransferase, and concentrations of serum metabolites [beta-hydroxybutyrate (BHB) and non-esterified fatty acids (NEFA)] of primiparous (n = 83) and multiparous (n = 213) Holstein cows were studied as possible predictors of retained fetal membranes (RFM), grade 2 clinical metritis (CM) and clinical endometritis (CEM). A logistic regression model was used to calculate odds ratios (OR) for the prevalence of CM diagnosed between 0-5, 6-10 and 11-20 days in milk (DIM) and for the prevalence of CEM diagnosed between 22-28 and 42-49 DIM. The activities of the examined serum enzymes did not show significant associations either with CM or with CEM. For NEFA sampled on days 0 and 5, an OR of 2.38 for CM 0-20 DIM and an OR of 2.58 for CM 11-20 DIM was found. For BHB sampled on days 0 and 5, an OR of 8.20 for CEM 22-28 and 42-49 DIM and an OR of 1.98 for CM 6-10 DIM were found. The prevalence of RFM was higher in ≥ 4 parity cows compared to primiparous cows (46.3% vs. 26.5%). BHB and NEFA levels measured between 0 and 5 DIM could have a predictive ability for postpartum uterine disorders such as RFM, CM and CEM.


Assuntos
Doenças dos Bovinos/metabolismo , Endometrite/veterinária , Metabolismo Energético , Enzimas/sangue , Paridade/fisiologia , Animais , Bovinos , Doenças dos Bovinos/diagnóstico , Endometrite/diagnóstico , Endometrite/metabolismo , Feminino , Hungria , Período Pós-Parto/fisiologia
10.
Acta Vet Hung ; 66(4): 613-624, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30580537

RESUMO

The authors monitored the postpartum period during the first seven weeks after calving at a Holstein-Friesian dairy farm in Hungary. Calvings occurred between 2013 and 2015 in three periods from June to November each year (n = 314). Data were collected from the farm record and ultrasonographic examinations were performed between 22 to 28 and 43 to 49 days in milk (DIM), respectively. The animals were followed until successful artificial insemination (AI), i.e. until becoming pregnant or until culling, but at most at 365 DIM. The prevalence of dystocia, twin calving, stillbirth rate and retained fetal membranes (RFM) was 23.2%, 3.8%, 3.5%, and 34.4%, respectively. Altogether 38.9% of the cows (n = 122) had bacterial complications of involution in the first 49 DIM. The prevalence of Grade 2 clinical (puerperal) metritis (CM) was 20.1% within 5 DIM, 10.5% between 6 to 10 DIM and 13.1% from 11 to 20 DIM, while 9.9% of the cows had clinical endometritis (CEM) between 21 and 28 DIM and 1.3% of the cows between 42 and 49 DIM, respectively. Pyometra was diagnosed in 1% of the cows between 21 and 28 DIM and 0.3% between 42 to 49 DIM, respectively. About 80% (80.6%) of the cows were inseminated at least once (n = 253). The success rate of the first AI was 26.9% (n = 68). Dystocia, twin calving, RFM, CM, CEM and cyclicity had no significant effect on the days between calving and first AI, however, according to the Kaplan-Meier analysis stillbirth significantly increased the number of days from calving to first AI (P = 0.039). According to the Kaplan- Meier analysis dystocia, twin calving, stillbirth, RFM, and cyclicity had no effect on the days open. In cows with CM developed within 5 DIM or with CEM diagnosed between 21 and 28 DIM the number of days open significantly decreased (P = 0.009 and P = 0.007, respectively), which confirms the importance of early diagnosis and treatment of uterine diseases. Similar surveys should be conducted to discover the risk factors for reproductive diseases in order to decrease the reproductive losses in dairy farms.


Assuntos
Doenças dos Bovinos/epidemiologia , Inseminação Artificial/veterinária , Complicações na Gravidez/veterinária , Prenhez , Animais , Bovinos , Doenças dos Bovinos/fisiopatologia , Distocia/epidemiologia , Distocia/fisiopatologia , Distocia/veterinária , Feminino , Hungria/epidemiologia , Incidência , Período Pós-Parto , Gravidez , Complicações na Gravidez/epidemiologia , Complicações na Gravidez/fisiopatologia , Prenhez/fisiologia , Prevalência
11.
Acta Biol Hung ; 67(4): 364-372, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28000510

RESUMO

By means of whole mount NADPH-diaphorase histochemistry the distribution pattern of primary sensory cells (PSC) and the pathway of their central processes in the ventral nerve cord (VNC) ganglia were investigated in the lumbricid earthworms, Eisenia fetida and Lumbricus terrestris. The distribution pattern of the stained structures seemed to be the same in both species investigated. Strong labelling occurred in sensory fibre branches of segmental nerves and in each of the sensory longitudinal axon bundles of VNC ganglia. Based on their anatomical location some NADPH-d positive central sensory cells were identified from among which the putative tactile receptors were characterized by constant, strong staining.


Assuntos
Sistema Nervoso Central/metabolismo , Gânglios Sensitivos/metabolismo , NADPH Desidrogenase/metabolismo , Oligoquetos/metabolismo , Nervos Periféricos/metabolismo , Células Receptoras Sensoriais/metabolismo , Animais , Corantes , Gânglios/metabolismo , Histocitoquímica
12.
Folia Biol (Krakow) ; 64(4): 275-284, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-29809366

RESUMO

Lumbricid earthworms are often exposed to polluted soil. They are also commonly subjected to various stimuli and attacks by predators that induce extrusion of coelomocyte-containing coelomic fluid and/or the loss of body segments followed by the renewal of immune-competent cells and regeneration of tissues/organs. The aim of our investigations was to test the effects of exposure of the earthworm Eisenia andrei to cadmium-polluted soil, combined with electrostimulation-induced depletion of coelomocytes (i.e. amoebocytes and chloragocyte-derived eleocytes) or the surgical amputation of posterior segments, on earthworm maturation, reproductive output, and regenerative processes. Experimental worms were maintained up to 7 weeks either in unpolluted soil or in soil spiked with cadmium chloride (500 mg/kg air-dried soil). In juvenile worms, sexual maturation (measured by clitellum formation) was delayed and cocoon production was inhibited in Cd-exposed worms. Coelomocytes were significantly depleted by electrostimulation and the kinetics of their recovery was similar in worms kept in clean and cadmium polluted soils, in both exposure conditions amoebocyte recovery was faster than recovery of riboflavin-storing eleocytes. In adult worms, soil cadmium exposure inhibited reproduction but, at macroanatomical level, had a negligible effect on regeneration of amputated posterior segments, visible only on histological cross-sections.


Assuntos
Cádmio/toxicidade , Oligoquetos/efeitos dos fármacos , Regeneração/efeitos dos fármacos , Poluentes do Solo/toxicidade , Animais , Oligoquetos/citologia , Oligoquetos/fisiologia , Maturidade Sexual/efeitos dos fármacos
13.
Front Psychiatry ; 15: 1354612, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38600983

RESUMO

Background: While literature is abundant on the negative mental health impact of the COVID-19 outbreak, few studies focus on the Central and Eastern European region. Objectives: We examined stress, burnout, and sleeping troubles among mental health professionals in the context of psychosocial risk factors related to participation in COVID care during the fourth and fifth waves. Materials and methods: Mental health professionals (N=268) completed an online cross-sectional survey in Hungary, between November 2021 and April 2022. Of the respondents, 58.2% directly participated in COVID care. The main data collection instrument was the Copenhagen Psychosocial Questionnaire (COPSOQ II), including 20 subscales on work-related psychosocial factors and 3 outcome scales (stress, burnout, and sleeping troubles). We added a question on competence transgression, and items on sociodemographic and professional background. Results: Participation in COVID care was associated with higher work pace (59.08 versus 49.78), more role conflicts (55.21 versus 45.93), lower scores on the influence at work (38.18 versus 51.79), predictability (44.71 versus 57.03), reward (55.82 versus 65.03), role clarity (70.19 versus 75.37), social support from supervisor (59.24 versus 65.55), job satisfaction (54.36 versus 62.84), trust regarding management (55.89 versus 67.86), justice and respect (44.51 versus 54.35) scales. Among those involved in COVID care, only the stress score was higher (47.96 vs. 42.35) in the total sample; however, among psychiatrists, both stress (52.16 vs. 38.60) and burnout scores (58.30 vs. 47.06) were higher. Stepwise multiple regression revealed that work-family conflict, emotional demands and workplace commitment were independent predictors of higher stress and burnout scores; furthermore, competence transgression had a significant effect on stress, and being a psychiatric specialist had a significant effect on burnout. These models explained 40.5% of the variance for stress and 39.8% for burnout. Conclusion: During the fourth and fifth waves, although COVID care was more well-organized, psychiatrists, as specialist physicians responsible for the quality of the care, were still experiencing challenges regarding their competence and influence at work, which may explain their increased levels of stress and burnout.

14.
SLAS Technol ; 28(2): 89-97, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36649783

RESUMO

The development of peptide-based pharmaceutics is a hot topic in the pharmaceutical industry and in basic research. However, from the research and development perspective there is an unmet need for new, alternative, solid-phase peptide synthesizers that are highly efficient, automated, robust, able to synthetize peptides in parallel, inexpensive (to obtain and operate), have potential to be scaled up, and even comply with the principles of green chemistry. Moreover, a peptide synthesizer of this type could also fill the gap in university research, and therefore speed the advancement of peptide-based pharmaceutical options. This paper presents a Tecan add-on peptide synthesizer (TaPSy), which has operational flexibility (coupling time: 15-30 min), can handle all manual synthesis methods, and is economical (solvent use: 34.5 mL/cycle, while handling 0.49 mmol scale/reactor, even with ≤3 equivalents of activated amino acid derivatives). Moreover, it can carry out parallel synthesis of up to 12 different peptides (0.49 mmol scale in each). TaPSy uses no heating or high pressure, while it is still resistant to external influences (operating conditions: atmospheric pressure, room temperature 20-40 ˚C, including high [>70%] relative humidity). The system's solvent can also be switched from DMF to a green and biorenewable solvent, γ-valerolactone (GVL), without further adjustment. The designed TaPSy system can produce peptides with high purity (>70%), even with the green GVL solvent alternative. In this paper we demonstrate the optimization path of a newly developed peptide synthesizer in the context of coupling reagents, reaction time and reagent equivalents applying for a synthesis of a model peptide. We compare the results by analytical characteristics (purity of raw material, crude yield, yield) and calculated overall cost of the syntheses of one mg of crude peptide using a specified set of reaction conditions.


Assuntos
Procedimentos Cirúrgicos Robóticos , Técnicas de Síntese em Fase Sólida , Humanos , Técnicas de Síntese em Fase Sólida/métodos , Peptídeos , Solventes
15.
Front Mol Neurosci ; 16: 1121479, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37256078

RESUMO

Introduction: Various methods have been used to determine the frequency components of seizures in scalp electroencephalography (EEG) and in intracortical recordings. Most of these methods rely on subjective or trial-and-error criteria for choosing the appropriate bandwidth for filtering the EEG or local field potential (LFP) signals to establish the frequency components that contribute most to the initiation and maintenance of seizure activity. The empirical mode decomposition (EMD) with the Hilbert-Huang transform is an unbiased method to decompose a time and frequency variant signal into its component non-stationary frequencies. The resulting components, i.e., the intrinsic mode functions (IMFs) objectively reflect the various non-stationary frequencies making up the original signal. Materials and methods: We employed the EMD method to analyze the frequency components and relative power of spontaneous electrographic seizures recorded in the dentate gyri of mice during the epileptogenic period. Epilepsy was induced in mice following status epilepticus induced by suprahippocampal injection of kainic acid. The seizures were recorded as local field potentials (LFP) with electrodes implanted in the dentate gyrus. We analyzed recording segments that included a seizure (mean duration 28 s) and an equivalent time period both before and after the seizure. Each segment was divided into non-overlapping 1 s long epochs which were then analyzed to obtain their IMFs (usually 8-10), the center frequencies of the respective IMF and their spectral root-mean-squared (RMS) power. Results: Our analysis yielded unbiased identification of the spectral components of seizures, and the relative power of these components during this pathological brain activity. During seizures, the power of the mid frequency components increased while the center frequency of the first IMF (with the highest frequency) dramatically decreased, providing mechanistic insights into how local seizures are generated. Discussion: We expect this type of analysis to provide further insights into the mechanisms of seizure generation and potentially better seizure detection.

16.
bioRxiv ; 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38106006

RESUMO

Brain rhythms provide the timing and concurrence of brain activity required for linking together neuronal ensembles engaged in specific tasks. In particular, the γ-oscillations (30-120 Hz) orchestrate neuronal circuits underlying cognitive processes and working memory. These oscillations are reduced in numerous neurological and psychiatric disorders, including early cognitive decline in Alzheimer's disease (AD). Here we report on a potent brain permeable small molecule, DDL-920 that increases γ-oscillations and improves cognition/memory in a mouse model of AD, thus showing promise as a new class of therapeutics for AD. As a first in CNS pharmacotherapy, our lead candidate acts as a potent, efficacious, and selective negative allosteric modulator (NAM) of the γ-aminobutyric acid type A receptors (GABA A Rs) assembled from α1ß2δ subunits. We identified these receptors through anatomical and pharmacological means to mediate the tonic inhibition of parvalbumin (PV) expressing interneurons (PV+INs) critically involved in the generation of γ-oscillations. Our approach is unique as it is meant to enhance cognitive performance and working memory in a state-dependent manner by engaging and amplifying the brain's endogenous γ-oscillations through enhancing the function of PV+INs.

17.
J Chem Inf Model ; 52(1): 233-42, 2012 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-22168379

RESUMO

Ligand-based approaches are particularly important in the hit identification process of drug discovery when no structural information on the target is available. Pharmacophore descriptors that use a topological representation of the ligands are usually fast enough to screen large compound libraries effectively when seeking novel lead candidates. One example of this kind is the Feature Tree descriptor, a reduced graph representation implemented in the FTrees software. In this study, we tested the screening efficiency of FTrees by both retrospective and prospective screens using known histamine H4 antagonists and serotonin transporter (SERT) inhibitors as query molecules. Our results demonstrate that FTrees can effectively find actives. Particularly when combined with a subsequent 2D fingerprint-based diversity selection, FTrees was found to be extremely effective at discovering a diverse set of scaffolds. Prospective screening of our in-house compound deck provided several novel H4 and SERT ligands that could serve as suitable starting points for further optimization.


Assuntos
Histamínicos/química , Receptores Acoplados a Proteínas G/química , Receptores Histamínicos/química , Inibidores Seletivos de Recaptação de Serotonina/química , Proteínas da Membrana Plasmática de Transporte de Serotonina/química , Software , Algoritmos , Desenho Assistido por Computador , Descoberta de Drogas , Histamínicos/farmacologia , Humanos , Estrutura Molecular , Receptores Acoplados a Proteínas G/antagonistas & inibidores , Receptores Histamínicos H4 , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia
18.
J Comput Aided Mol Des ; 26(5): 577-82, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22366954

RESUMO

A Merck molecular force field classical potential combined with Poisson-Boltzmann electrostatics (MMFF/PB) has been used to estimate the binding free energy of seven guest molecules (six tertiary amines and one primary amine) into a synthetic receptor (acyclic cucurbit[4]uril congener) and two benzimidazoles into cyclic cucurbit[7]uril (CB[7]) and cucurbit[8]uril (CB[8]) hosts. In addition, binding enthalpies for the benzimidazoles were calculated with density functional theory (DFT) using the B3LYP functional and a polarizable continuum model (PCM). Although in most cases the MMFF/PB approach returned reasonable agreements with the experiment (±2 kcal/mol), significant, much larger deviations were reported in the case of three host-guest pairs. All four binding enthalpy predictions with the DFT/PCM method suffered 70% or larger deviations from the calorimetry data. Results are discussed in terms of the molecular models used for guest-host complexation and the quality of the intermolecular potentials.


Assuntos
Aminas/química , Modelos Moleculares , Termodinâmica , Benzimidazóis/química , Hidrocarbonetos Aromáticos com Pontes/química , Calorimetria , Imidazóis/química , Estrutura Molecular
19.
Environ Sci Technol ; 46(7): 4166-73, 2012 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-22432789

RESUMO

Little is known about the potential threats of silver nanoparticles (AgNPs) to ecosystem health, with no detailed report existing on the stress and immune responses of soil invertebrates. Here we use earthworm primary cells, cross-referencing to human cell cultures with a particular emphasis on the conserved biological processes, and provide the first in vitro analysis of molecular and cellular toxicity mechanisms in the earthworm Eisenia fetida exposed to AgNPs (83 ± 22 nm). While we observed a clear difference in cytotoxicity of dissolved silver salt on earthworm coelomocytes and human cells (THP-1 cells, differentiated THP-1 cells and peripheral blood mononuclear cells), the coelomocytes and differentiated (macrophage-like) THP-1 cells showed a similar response to AgNPs. Intracellular accumulation of AgNPs in the coelomocytes, predominantly in a phagocytic population, was evident by several methods including transmission electron microscopy. Molecular signatures of oxidative stress and selected biomarker genes probed in a time-resolved manner suggest early regulation of oxidative stress genes and subsequent alteration of immune signaling processes following the onset of AgNP exposure in the coelomocytes and THP-1 cells. Our findings provide mechanistic clues on cellular innate immunity toward AgNPs that is likely to be evolutionarily conserved across the animal kingdom.


Assuntos
Evolução Biológica , Imunidade/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Oligoquetos/efeitos dos fármacos , Oligoquetos/imunologia , Prata/toxicidade , Estresse Fisiológico/efeitos dos fármacos , Animais , Morte Celular/efeitos dos fármacos , Linhagem Celular , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Imunidade/genética , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Masculino , Nanopartículas Metálicas/ultraestrutura , Espécies Reativas de Oxigênio/metabolismo , Estresse Fisiológico/genética , Fatores de Tempo
20.
Comp Biochem Physiol A Mol Integr Physiol ; 163(2): 199-209, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22710253

RESUMO

The cytochemical and functional characteristics of chloragocytes of both 'control' and cold-stressed Eisenia fetida were examined. Flow cytometry revealed the heterogeneity of chloragocytes: the first group was characterized by low, the second one by high acid phosphatase (AcP) content. In 'control' animals the former, in cold-stressed ones the latter type were the dominant form. The elevated AcP-activity correlated with the accumulation of autophagic vacuoles (AVs) in chloragocytes. Both AVs and all small chloragosomes showed high AcP activity, while most of the large chloragosomes did not display any. Most 'control' granules (0.75-1.25 µm) contained high amounts of Ca and P, with less and variable quantities of S, Cl, K, Fe and Zn. Small chloragosomes with low Ca and P concentrations were seldom found. In cold-stressed animals the number of small granules (0.25-0.75 µm) increased up to 40% of total population. Their Ca and P contents were significantly lower; S and Fe concentrations were higher than those of large chloragosomes (1.0-1.5 µm). Our results prove that the formation and elemental composition of chloragosomes can be influenced by environmental stressors and suggest that the mature chloragosomes are tertiary lysosomes and their formation is coupled to autophagocytosis.


Assuntos
Vasos Sanguíneos/citologia , Cálcio/metabolismo , Grânulos Citoplasmáticos/metabolismo , Oligoquetos/metabolismo , Fósforo/metabolismo , Estresse Fisiológico , Fosfatase Ácida/metabolismo , Animais , Temperatura Baixa , Grânulos Citoplasmáticos/enzimologia , Grânulos Citoplasmáticos/ultraestrutura , Sistema Digestório/irrigação sanguínea , Oligoquetos/citologia , Oligoquetos/fisiologia , Forma das Organelas
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