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1.
J Neurosci ; 43(5): 846-862, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36564184

RESUMO

Stress disorders impair sleep and quality of life; however, their pathomechanisms are unknown. Prolactin-releasing peptide (PrRP) is a stress mediator; we therefore hypothesized that PrRP may be involved in the development of stress disorders. PrRP is produced by the medullary A1/A2 noradrenaline (NA) cells, which transmit stress signals to forebrain centers, and by non-NA cells in the hypothalamic dorsomedial nucleus. We found in male rats that both PrRP and PrRP-NA cells innervate melanin-concentrating hormone (MCH) producing neurons in the dorsolateral hypothalamus (DLH). These cells serve as a key hub for regulating sleep and affective states. Ex vivo, PrRP hyperpolarized MCH neurons and further increased the hyperpolarization caused by NA. Following sleep deprivation, intracerebroventricular PrRP injection reduced the number of REM sleep-active MCH cells. PrRP expression in the dorsomedial nucleus was upregulated by sleep deprivation, while downregulated by REM sleep rebound. Both in learned helplessness paradigm and after peripheral inflammation, impaired coping with sustained stress was associated with (1) overactivation of PrRP cells, (2) PrRP protein and receptor depletion in the DLH, and (3) dysregulation of MCH expression. Exposure to stress in the PrRP-insensitive period led to increased passive coping with stress. Normal PrRP signaling, therefore, seems to protect animals against stress-related disorders. PrRP signaling in the DLH is an important component of the PrRP's action, which may be mediated by MCH neurons. Moreover, PrRP receptors were downregulated in the DLH of human suicidal victims. As stress-related mental disorders are the leading cause of suicide, our findings may have particular translational relevance.SIGNIFICANCE STATEMENT Treatment resistance to monoaminergic antidepressants is a major problem. Neuropeptides that modulate the central monoaminergic signaling are promising targets for developing alternative therapeutic strategies. We found that stress-responsive prolactin-releasing peptide (PrRP) cells innervated melanin-concentrating hormone (MCH) neurons that are crucial in the regulation of sleep and mood. PrRP inhibited MCH cell activity and enhanced the inhibitory effect evoked by noradrenaline, a classic monoamine, on MCH neurons. We observed that impaired PrRP signaling led to failure in coping with chronic/repeated stress and was associated with altered MCH expression. We found alterations of the PrRP system also in suicidal human subjects. PrRP dysfunction may underlie stress disorders, and fine-tuning MCH activity by PrRP may be an important part of the mechanism.


Assuntos
Hormônios Hipotalâmicos , Privação do Sono , Ratos , Masculino , Humanos , Animais , Hormônio Liberador de Prolactina/farmacologia , Hormônio Liberador de Prolactina/metabolismo , Privação do Sono/metabolismo , Transtornos do Humor/etiologia , Qualidade de Vida , Ratos Wistar , Hormônios Hipotalâmicos/metabolismo , Sono/fisiologia , Neurônios/fisiologia , Norepinefrina/metabolismo
2.
Eur Radiol ; 2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-37921926

RESUMO

OBJECTIVES: The introduction of low-dose CT (LDCT) altered the landscape of lung cancer (LC) screening and contributed to the reduction of mortality rates worldwide. Here we report the final results of HUNCHEST-II, the largest population-based LDCT screening program in Hungary, including the screening and diagnostic outcomes, and the characteristics of the LC cases. METHODS: A total of 4215 high-risk individuals aged between 50 and 75 years with a smoking history of at least 25 pack-years were assigned to undergo LDCT screening. Screening outcomes were determined based on the volume, growth, and volume doubling time of pulmonary nodules or masses. The clinical stage distribution of screen-detected cancers was compared with two independent practice-based databases consisting of unscreened LC patients. RESULTS: The percentage of negative and indeterminate tests at baseline were 74.2% and 21.7%, respectively, whereas the prevalence of positive LDCT results was 4.1%. Overall, 76 LC patients were diagnosed throughout the screening rounds (1.8% of total participants), out of which 62 (1.5%) patients were already identified in the first screening round. The overall positive predictive value of a positive test was 58%. Most screen-detected malignancies were stage I LCs (60.7%), and only 16.4% of all cases could be classified as stage IV disease. The percentage of early-stage malignancies was significantly higher among HUNCHEST-II screen-detected individuals than among the LC patients in the National Koranyi Institute of Pulmonology's archive or the Hungarian Cancer Registry (p < 0.001). CONCLUSIONS: HUNCHEST-II demonstrates that LDCT screening for LC facilitates early diagnosis, thus arguing in favor of introducing systematic LC screening in Hungary. CLINICAL RELEVANCE STATEMENT: HUNCHEST-II is the so-far largest population-based low-dose CT screening program in Hungary. A positive test's overall positive predictive value was 58%, and most screen-detected malignancies were early-stage lesions. These results pave the way for expansive systematic screening in the region. KEY POINTS: • Conducted in 18 medical facilities, HUNCHEST-II is the so far largest population-based low-dose CT screening program in Hungary. • The vast majority of screen-detected malignancies were early-stage lung cancers, and the overall positive predictive value of a positive test was 58%. • HUNCHEST-II facilitates early diagnosis, thus arguing in favor of introducing systematic lung cancer screening in Hungary.

3.
Int J Mol Sci ; 24(21)2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37958750

RESUMO

Nano-range bioactive colloidal carrier systems are envisaged to overcome the challenges associated with treatments of numerous diseases. Lipid nanoparticles (LNPs), one of the extensively investigated drug delivery systems, not only improve pharmacokinetic parameters, transportation, and chemical stability of encapsulated compounds but also provide efficient targeting and reduce the risk of toxicity. Over the last decades, nature-derived polyphenols, vitamins, antioxidants, dietary supplements, and herbs have received more attention due to their remarkable biological and pharmacological health and medical benefits. However, their poor aqueous solubility, compromised stability, insufficient absorption, and accelerated elimination impede research in the nutraceutical sector. Owing to the possibilities offered by various LNPs, their ability to accommodate both hydrophilic and hydrophobic molecules and the availability of various preparation methods suitable for sensitive molecules, loading natural fragile molecules into LNPs offers a promising solution. The primary objective of this work is to explore the synergy between nature and nanotechnology, encompassing a wide range of research aimed at encapsulating natural therapeutic molecules within LNPs.


Assuntos
Suplementos Nutricionais , Nanopartículas , Disponibilidade Biológica , Lipossomos , Sistemas de Liberação de Medicamentos , Nanopartículas/química
4.
Eur Radiol ; 32(7): 4457-4467, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35247089

RESUMO

OBJECTIVES: Lung cancer (LC) kills more people than any other cancer in Hungary. Hence, there is a clear rationale for considering a national screening program. The HUNCHEST pilot program primarily aimed to investigate the feasibility of a population-based LC screening in Hungary, and determine the incidence and LC probability of solitary pulmonary nodules. METHODS: A total of 1890 participants were assigned to undergo low-dose CT (LDCT) screening, with intervals of 1 year between procedures. Depending on the volume, growth, and volume doubling time (VDT), screenings were defined as negative, indeterminate, or positive. Non-calcified lung nodules with a volume > 500 mm3 and/or a VDT < 400 days were considered positive. LC diagnosis was based on histology. RESULTS: At baseline, the percentage of negative, indeterminate, and positive tests was 81.2%, 15.1%, and 3.7%, respectively. The frequency of positive and indeterminate LDCT results was significantly higher in current smokers (vs. non-smokers or former smokers; p < 0.0001) and in individuals with COPD (vs. those without COPD, p < 0.001). In the first screening round, 1.2% (n = 23) of the participants had a malignant lesion, whereas altogether 1.5% (n = 29) of the individuals were diagnosed with LC. The overall positive predictive value of the positive tests was 31.6%. Most lung malignancies were diagnosed at an early stage (86.2% of all cases). CONCLUSIONS: In terms of key characteristics, our prospective cohort study appears consistent to that of comparable studies. Altogether, the results of the HUNCHEST pilot program suggest that LDCT screening may facilitate early diagnosis and thus curative-intent treatment in LC. KEY POINTS: • The HUNCHEST pilot study is the first nationwide low-dose CT screening program in Hungary. • In the first screening round, 1.2% of the participants had a malignant lesion, whereas altogether 1.5% of the individuals were diagnosed with lung cancer. • The overall positive predictive value of the positive tests in the HUNCHEST screening program was 31.6%.


Assuntos
Neoplasias Pulmonares , Doença Pulmonar Obstrutiva Crônica , Detecção Precoce de Câncer/métodos , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/epidemiologia , Programas de Rastreamento , Projetos Piloto , Estudos Prospectivos , Tomografia Computadorizada por Raios X/métodos
5.
BMC Pediatr ; 22(1): 648, 2022 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-36348320

RESUMO

AIM: Teaching Basic Life Support (BLS) in schools is a key initiative to improve the survival rates after out-of-hospital cardiac arrest. Low-cost training materials can reach a wider population. Our aim was to compare the effectiveness of using teaching cards with the traditional instructor-led and combined methods on BLS skills and attitude and to evaluate the long-term effects after two months. METHODS: A quasi-experimental combination design study. Two hundred sixty-three schoolchildren aged 6 to 10 years were assigned to three groups with different methods to teach BLS: teaching card group (n = 100), traditional instructor-led teaching group (n = 91), combined teaching group (n = 72). BLS skills and attitude were measured and compared before the training (T0), after the training (T1), and two months later (T2). RESULTS: BLS skills improved in every group at T1 compared to T0 (p < 0.001) and remained higher at T2 than at T0 in almost all cases (p < 0.001). Skill performance was similar in most of the skills between the three groups at T1. The best skill scores acquired were calling the ambulance and the correct hand position by chest compression. Positioning the head during check the breathing was more effective in the traditional group (48.4%) and combined group (61.1%) than in the teaching card group (19.0%) (p < 0.001) at T1. However, some skills improved significantly in the teaching card group at T2: check breathing for 10 s (p = 0.016); positioning the head by check breathing (p < 0.001); and positioning the head by ventilation (p = 0.011). Attitude did not change significantly in any of the groups (p > 0.05). Furthermore, the level of attitude was inferior in the teaching card group compared with the traditional (p = 0.005), and the combined groups (p = 0.049). CONCLUSION: Using low-cost materials for teaching BLS for young schoolchildren can improve their skills, however, could not improve attitudes. Teaching cards were not inferior compared to traditional and combined methods in some skills but inferior in others. Therefore, hands-on training opportunity is still important. Teaching cards are useful for long-term learning. To learn correctly the whole sequence of BLS is difficult for 6 to 10 years-old children, however, they are able to learn more BLS-related skills separately.


Assuntos
Recursos Audiovisuais , Reanimação Cardiopulmonar , Instituições Acadêmicas , Criança , Humanos , Atitude , Reanimação Cardiopulmonar/educação , Avaliação Educacional , Aprendizagem , Ensino , Recursos Audiovisuais/economia
6.
Eur Radiol ; 31(5): 2819-2824, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33051732

RESUMO

PURPOSE: The identification of patients infected by SARS-CoV-2 is highly important to control the disease; however, the clinical presentation is often unspecific and a large portion of the patients develop mild or no symptoms at all. For this reason, there is an emphasis on evaluating diagnostic tools for screening. Chest CT scans are emerging as a useful tool in the diagnostic process of viral pneumonia cases associated with COVID-19. This review examines the sensitivity, specificity, and feasibility of chest CT in detecting COVID-19 compared with real-time polymerase chain reaction (RT-PCR). METHODS: Sensitivity and specificity of chest CT in detecting COVID-19 in its various phases was compared using RT-PCR as a gold standard. A "reverse calculation approach" was applied and treated chest CT as a hypothetical gold standard and compared RT-PCR to it point out the flaw of the standard approach. RESULTS: High sensitivity (67-100%) and relatively low specificity (25-80%) was reported for the CT scans. However, the sensitivity of RT-PCR was reported to be modest (53-88%), hence cannot serve as an appropriate ground truth. The "reverse calculation approach" showed that CT could have a higher specificity (83-100%) if we consider the modest sensitivity of the RT-PCR. CONCLUSIONS: The sensitivity and specificity of the chest CT in diagnosing COVID-19 and the radiation exposure have to be judged together. Arguments are presented that chest CT scans have added value in diagnosing COVID-19 especially in patients, who exhibit typical clinical symptoms and have negative RT-PCR results in highly infected regions. KEY POINTS: • CT scans have higher specificity if we take into account the low sensitivity of the RT-PCR. • Avoid chest CT as a sole diagnostic approach for COVID-19 infection. • Patients who had negative RT-PCR result with typical clinical symptoms in highly infected regions or with close contact of COVID-19-infected patients; the use of chest CT is warranted.


Assuntos
COVID-19 , Pneumonia Viral , Humanos , SARS-CoV-2 , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X
7.
BMC Pulm Med ; 21(1): 225, 2021 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-34253193

RESUMO

BACKGROUND: Cystic fibrosis (CF) is a life-threatening multiorgan genetic disease, particularly affecting the lungs, where recurrent infections are the main cause of reduced life expectancy. In CF, mutations in the gene encoding the cystic fibrosis transmembrane conductance regulator (CFTR) protein impair transepithelial electrolyte and water transport, resulting in airway dehydration, and a thickening of the mucus associated with abnormal viscoelastic properties. Our aim was to develop a rheological method to assess the effects of hypertonic saline (NaCl) and NaHCO3 on CF sputum viscoelasticity in vitro, and to identify the critical steps in sample preparation and in the rheological measurements. METHODS: Sputum samples were mixed with hypertonic salt solutions in vitro in a ratio of either 10:4 or 10:1. Distilled water was applied as a reference treatment. The rheological properties of sputum from CF patients, and the effects of these in vitro treatments, were studied with a rheometer at constant frequency and strain, followed by frequency sweep tests, where storage modulus (G'), loss modulus (G″) and loss factor were determined. RESULTS: We identified three distinct categories of sputum: (i) highly elastic (G' > 100,000 Pa), (ii) elastic (100,000 Pa > G' > 1000 Pa), and (iii) viscoelastic (G' < 1000). At the higher additive ratio (10:4), all of the added solutions were found to significantly reduce the gel strength of the sputum, but the most pronounced changes were observed with NaHCO3 (p < 0.001). Samples with high elasticity exhibited the greatest changes while, for less elastic samples, a weakening of the gel structure was observed when they were treated with water or NaHCO3, but not with NaCl. For the viscoelastic samples, the additives did not cause significant changes in the parameters. When the lower additive ratio (10:1) was used, the mean values of the rheological parameters usually decreased, but the changes were not statistically significant. CONCLUSION: Based on the rheological properties of the initial sputum samples, we can predict with some confidence the treatment efficacy of each of the alternative additives. The marked differences between the three categories suggest that it is advisable to evaluate each sample individually using a rheological approach such as that described here.


Assuntos
Fibrose Cística/fisiopatologia , Solução Salina Hipertônica/farmacologia , Bicarbonato de Sódio/farmacologia , Escarro/fisiologia , Elasticidade , Feminino , Humanos , Técnicas In Vitro , Masculino , Reologia , Manejo de Espécimes , Viscosidade
8.
Sensors (Basel) ; 20(17)2020 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-32825145

RESUMO

Accurate and reliable measurement of the electrical impedance spectrum is an essential requirement in order to draw relevant conclusions in many fields and a variety of applications; in particular, for biological processes. Even in the state-of-the-art methods developed for this purpose, the accuracy and efficacy of impedance measurements are reduced in biological systems, due to the regular occurrence of parameters causing measurement errors such as residual impedance, parasitic capacitance, generator anomalies, and so on. Recent observations have reported the necessity of decreasing such inaccuracies whenever measurements are performed in the ultra-low frequency range, as the above-mentioned errors are almost entirely absent in such cases. The current research work proposes a method which can reject the anomalies listed above when measuring in the ultra-low frequency range, facilitating data collection at the same time. To demonstrate our hypothesis, originating from the consideration of the determinant role of the measuring frequency, a physical model is proposed to examine the effectiveness of our method by measuring across the commonly used vs. ultra-low frequency ranges. Validation measurements reflect that the range of frequencies and the accuracy is much greater than in state-of-the-art methods. Using the proposed new impedance examination technique, biological system characterization can be carried out more accurately.


Assuntos
Impedância Elétrica , Capacitância Elétrica
9.
Int J Mol Sci ; 21(14)2020 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-32698503

RESUMO

Chemotherapy-induced differentiation of immature myeloid progenitors, such as acute myeloid leukemia (AML) cells or myeloid-derived suppressor cells (MDSCs), has remained a challenge for the clinicians. Testing our imidazo[1,2-b]pyrazole-7-carboxamide derivative on HL-60 cells, we obtained ERK phosphorylation as an early survival response to treatment followed by the increase of the percentage of the Bcl-xlbright and pAktbright cells. Following the induction of Vav1 and the AP-1 complex, a driver of cellular differentiation, FOS, JUN, JUNB, and JUND were elevated on a concentration and time-dependent manner. As a proof of granulocytic differentiation, the cells remained non-adherent, the expression of CD33 decreased; the granularity, CD11b expression, and MPO activity of HL-60 cells increased upon treatment. Finally, viability of HL-60 cells was hampered shown by the depolarization of mitochondria, activation of caspase-3, cleavage of Z-DEVD-aLUC, appearance of the sub-G1 population, and the leakage of the lactate-dehydrogenase into the supernatant. We confirmed the differentiating effect of our drug candidate on human patient-derived AML cells shown by the increase of CD11b and decrease of CD33+, CD7+, CD206+, and CD38bright cells followed apoptosis (IC50: 80 nM) after treatment ex vivo. Our compound reduced both CD11b+/Ly6C+ and CD11b+/Ly6G+ splenic MDSCs from the murine 4T1 breast cancer model ex vivo.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Leucemia Mieloide Aguda/tratamento farmacológico , Células Supressoras Mieloides/efeitos dos fármacos , Pirazóis/farmacologia , Animais , Antineoplásicos/química , Diferenciação Celular/efeitos dos fármacos , Feminino , Células HL-60 , Humanos , Leucemia Mieloide Aguda/metabolismo , Masculino , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade , Células Supressoras Mieloides/citologia , Células Supressoras Mieloides/metabolismo , Pirazóis/química , Células Tumorais Cultivadas , Adulto Jovem
10.
Int J Mol Sci ; 21(1)2019 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-31881770

RESUMO

The treatment of metastatic breast cancer remained a challenge despite the recent breakthrough in the immunotherapy regimens. Here, we addressed the multidimensional immunophenotyping of 4T1 metastatic breast cancer by the state-of-the-art single cell mass cytometry (CyTOF). We determined the dose and time dependent cytotoxicity of cisplatin on 4T1 cells by the xCelligence real-time electronic sensing assay. Cisplatin treatment reduced tumor growth, number of lung metastasis, and the splenomegaly of 4T1 tumor bearing mice. We showed that cisplatin inhibited the tumor stroma formation, the polarization of carcinoma-associated fibroblasts by the diminished proteolytic activity of fibroblast activating protein. The CyTOF analysis revealed the emergence of CD11b+/Gr-1+/CD44+ or CD11b+/Gr-1+/IL-17A+ myeloid-derived suppressor cells (MDSCs) and the absence of B220+ or CD62L+ B-cells, the CD62L+/CD4+ and CD62L+/CD8+ T-cells in the spleen of advanced cancer. We could show the immunomodulatory effect of cisplatin via the suppression of splenic MDSCs and via the promotion of peripheral IFN-γ+ myeloid cells. Our data could support the use of low dose chemotherapy with cisplatin as an immunomodulatory agent for metastatic triple negative breast cancer.


Assuntos
Cisplatino/farmacologia , Regulação para Baixo/efeitos dos fármacos , Células Supressoras Mieloides/metabolismo , Células Neoplásicas Circulantes/metabolismo , Animais , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cisplatino/uso terapêutico , Endopeptidases , Feminino , Gelatinases/metabolismo , Humanos , Receptores de Hialuronatos/metabolismo , Imunofenotipagem , Interferon gama/metabolismo , Interleucina-17/metabolismo , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Células Supressoras Mieloides/citologia , Serina Endopeptidases/metabolismo , Transplante Heterólogo
11.
Water Sci Technol ; 79(10): 1905-1911, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31294707

RESUMO

We studied water loss performance in a model plant, the Tufted sedge (Carex elata All.), which is an active water balance component of subsurface flow constructed wetlands. Due to active regulation of transpiration, the volume and dynamics of water loss in these constructed wetlands are difficult to plan without preliminary and targeted measurements and calculations with regard to the specific plant component. We estimated transpiration values in the laboratory based on daytime transpiration ranges for spring, summer and autumn, and examined the transpiration effect of the hydraulic load. During spring, water loss via transpiration can reach 83% of the hydraulic load on certain days. During summer, this value can increase to 100% of the hydraulic load, which means that the daytime transpiration can significantly affect effluent concentration. Air humidity proved to be the most critical environmental factor for water loss resulting from transpiration, therefore a water discharge plan designed in such a way as to be able to also adjust soil moisture is the key to optimal water circulation at the system level.


Assuntos
Solo , Eliminação de Resíduos Líquidos/métodos , Áreas Alagadas , Estações do Ano , Água
12.
J Org Chem ; 83(7): 3570-3581, 2018 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-29498845

RESUMO

A ZnCl2-catalyzed diastereoselective Joullié-Ugi three-component reaction from 2 H-azirines, isocyanides, and carboxylic acids was established. The protocol allows the preparation of highly and diversely functionalized N-acylaziridine-2-carboxamide derivatives in up to 82% isolated yields. Moreover, the applicability of N-acylaziridines is demonstrated through a variety of transformations.

13.
Molecules ; 23(4)2018 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-29597330

RESUMO

The aim of this article was to study the trans-epithelial absorption to reach the blood and to target the brain by axonal transport using nasal formulations with nanonized meloxicam (nano MEL spray) and its salt form known as meloxicam potassium monohydrate (MELP spray). The physicochemical properties and the mucoadhesivity of nasal formulations were controlled. In vitro and in vivo studies were carried out. These forms were first investigated in "nose-to-brain" relation. It was found that the in vitro study and in vivo study did not show any significant correlation. In vitro experiments demonstrated faster dissolution rate and higher diffusion of MELP from the spray compared with the nano MEL spray. The administration of the nano MEL spray resulted in faster absorption and constant plasma concentration of the drug after five minutes of administration as compared to MELP. The axonal transport of the drug was justified. MEL appeared in the brain tissues after the first five minutes of administration in the case of both spray forms, but its amount was too small in comparison with the total plasma concentration. The application of the nano MEL spray resulted in the same AUC in the brain as the intravenous injection. The "nose-to-blood" results predicted the nasal applicability of MEL and MELP in pain management. The "nose-to-brain" pathway requires further study.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Absorção Nasal , Tiazinas , Tiazóis , Administração Intranasal , Animais , Sistemas de Liberação de Medicamentos/instrumentação , Masculino , Meloxicam , Ratos , Ratos Sprague-Dawley , Tiazinas/química , Tiazinas/farmacocinética , Tiazinas/farmacologia , Tiazóis/química , Tiazóis/farmacocinética , Tiazóis/farmacologia
14.
Amino Acids ; 48(9): 2261-6, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27262310

RESUMO

Amnesia is a deficit in memory caused by brain damage, disease, or trauma. Until now, there are no successful medications on the drug market available to treat amnesia. Short analogs and mimetics of human urocortin 3 (Ucn 3) tripeptide were synthetized and tested for their action against amnesia induced by eletroconvulsion in mice. Among the 16 investigated derivatives of Ucn 3 tripeptide, eight compounds displayed antiamnesic effect. Our results proved that the configuration of chiral center of glutamine does not affect the antiamnesic properties. Alkyl amide or isoleucyl amide at the C-terminus may lead to antiamnesic compounds. As concerned the N-terminus, acetyl, Boc, and alkyl ureido moieties were found among the active analogs, but the free amino function at the N-terminus usually led to an inactive derivatives. These observations may lead to the design and synthesis of small peptidomimetics and amino acid derivatives as antiamnesic drug candidates, although the elucidation of the mechanism of the action requires further investigations.


Assuntos
Amnésia/tratamento farmacológico , Hormônio Liberador da Corticotropina/química , Oligopeptídeos , Peptidomiméticos , Urocortinas/química , Amnésia/metabolismo , Amnésia/patologia , Amnésia/fisiopatologia , Animais , Feminino , Humanos , Camundongos , Oligopeptídeos/síntese química , Oligopeptídeos/química , Oligopeptídeos/farmacologia , Peptidomiméticos/síntese química , Peptidomiméticos/química , Peptidomiméticos/farmacologia
15.
Pharmaceutics ; 16(3)2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38543207

RESUMO

This study focuses on how to define an Analytical Target Profile (ATP) which is intended for use in practice and on facilitating the selection of in vitro release test (IVRT) technology for diclofenac sodium topical hydrogel and cream. The implementation involves incorporating the new draft guidelines of the International Council for Harmonisation (ICH Q14) and USP (United States Pharmacopeia) Chapter 1220. Four IVRT apparatuses were compared (USP Apparatus II with immersion cell, USP Apparatus IV with semisolid adapter, static vertical diffusion cell, and a new, in-house-developed flow-through diffusion cell) with the help of the ATP. Performance characteristics such as accuracy, precision, cumulative amount released at the end of the IVRT experiment, and robustness were investigated. We found that the best apparatus for developing IVRT quality control (QC) tests in both cases was USP II with an immersion cell. All four different IVRT apparatuses were compared with each other and with the data found in the literature.

16.
Pharmaceutics ; 16(2)2024 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-38399341

RESUMO

Medicated foams have emerged as promising alternatives to traditional carrier systems in pharmaceutical research. Their rapid and convenient application allows for effective treatment of extensive or hirsute areas, as well as sensitive or inflamed skin surfaces. Foams possess excellent spreading capabilities on the skin, ensuring immediate drug absorption without the need for intense rubbing. Our research focuses on the comparison of physicochemical and biopharmaceutical properties of three drug delivery systems: foam, the foam bulk liquid, and a conventional hydrogel. During the development of the composition, widely used diclofenac sodium was employed. The safety of the formulae was confirmed through an in vitro cytotoxicity assay. Subsequently, the closed Franz diffusion cell was used to determine drug release and permeation in vitro. Ex vivo Raman spectroscopy was employed to investigate the presence of diclofenac sodium in various skin layers. The obtained results of the foam were compared to the bulk liquid and to a conventional hydrogel. In terms of drug release, the foam showed a rapid release, with 80% of diclofenac released within 30 min. In summary, the investigated foam holds promising potential as an alternative to traditional dermal carrier systems, offering faster drug release and permeation.

17.
Eur J Pharm Sci ; 193: 106666, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38081373

RESUMO

Transdermal delivery of active ingredients is a challenge for pharmaceutical technology due to their inadequate penetration properties and the barrier function of the skin. The necessity of painless, effective, topical therapy for the aging population is growing, and a variety of diclofenac sodium-containing semi-solid preparations are available to alleviate the symptoms of these ailments. Our purpose was to formulate a novel composition with higher drug content to enhance drug release and permeation, thereby providing more effective therapy. Another goal was to maintain the concentration of the organic solvent mixture below 30%, to protect the skin barrier. Firstly, literature and market research were conducted, based on which the appropriate excipients for the target formulation were selected. Solubility tests were conducted with binary and ternary mixtures. As a result, the optimal ternary mixture was chosen. Hydrogels containing 1, 5, and 7% of diclofenac sodium were prepared and the stability of the formulations were studied by microscopic measurements and cytotoxicity test were carried out of the components also. The release and permeation of diclofenac sodium were investigated in different concentrations. It can be concluded that we have succeeded in preparing a topically applicable stable diclofenac sodium hydrogel with higher concentration, drug release, and improved skin permeation than the formulations available on the market.


Assuntos
Anti-Inflamatórios não Esteroides , Diclofenaco , Absorção Cutânea , Hidrogéis/metabolismo , Pele/metabolismo , Administração Cutânea
18.
Int J Pharm ; 660: 124377, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38914351

RESUMO

Lidocaine is generally recognized and preferred for local anaesthesia, but in addition, studies have described additional benefits of lidocaine in cancer therapy, inflammation reduction, and wound healing. These properties contribute to its increasing importance in dermatological applications, and not only in pain relief but also in other potential therapeutic outcomes. Therefore, the purpose of our study was to enhance lidocaine delivery through the skin. A stable nanostructured lipid carrier (NLC), as a passive permeation enhancer, was developed using a 23 full factorial design. The nanosystems were characterized by crystallinity behaviour, particle size, zeta potential, encapsulation efficiency measurements, and one of them was selected for further investigation. Then, NLC gel was formulated for dermal application and compared to a traditional dermal ointment in terms of physicochemical (rheological behaviour) and biopharmaceutical (qualitative Franz diffusion and quantitative Raman investigations) properties. The study also examined the use of 3D printed solid microneedles as active permeation enhancers for these systems, offering a minimally invasive approach to enhance transdermal drug delivery. By actively facilitating drug permeation through the skin, microneedles can complement the passive transport achieved by NLCs, thereby providing an innovative and synergistic approach to improving lidocaine delivery.

19.
PLoS One ; 19(1): e0297023, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38232069

RESUMO

OBJECTIVES: Emerging results indicate that, in COVID-19, thromboembolic complications contribute to the high mortality and morbidity. Previous research showed that the prevalence of pulmonary embolism (PE) is between 25-50% in COVID-19 patients, however, most of these reports are based on data from patients with severe pneumonia, treated in intensive care units. MATERIALS AND METHODS: We conducted a retrospective, single-center, observational study to estimate the prevalence of PE in COVID-19 patients who underwent CT angiography and to identify the most important predictors. Adult outpatients with COVID-19, who presented at our COVID Outpatient Clinic between 1st and 31st of March in 2021 and underwent CTA examination were included in this study. Multiple linear regression analysis was used to identify predictors of PE in COVID-19 patients. The predictors were: age, gender, disease duration, CT severity index and log-transformed quantitative D-dimer (logQDDIM) value. RESULTS: 843 COVID-19 patients were included into the study. 82.56% (693 patients) of the infected patients had a pulmonary CTA examination and D-dimer levels (mean age: 59.82 years ± 15.66). 7.61% (53 patients) of the patients had PE. 2.02% (14 patients) of the patients had main branch or lobar PE. The multiple regression analysis found that only logQDDIM was a significant predictor. A logQDDIM cut-off value of 0.0169 (1.0171 ug/ml serum D-dimer) predicted PE with 99% sensitivity (p<0.0001, degree-of-freedom = 570, AUC = 0.72). CONCLUSIONS: We demonstrated in a large cohort of COVID-19 patients that a cut-off value of QDDIM of 1ug/ml can exclude pulmonary embolism in an outpatient setting, implicating that QDDIM might potentially supersede CTA as a screening approach in COVID-19 outpatient clinics.


Assuntos
COVID-19 , Embolia Pulmonar , Adulto , Humanos , Pessoa de Meia-Idade , Angiografia por Tomografia Computadorizada , COVID-19/diagnóstico , Pacientes Ambulatoriais , Estudos Retrospectivos , Embolia Pulmonar/diagnóstico por imagem , Produtos de Degradação da Fibrina e do Fibrinogênio/análise
20.
Peptides ; 175: 171169, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38340898

RESUMO

The goal of the present study is to investigate the role of intraamygdaloid oxytocin in learning-related mechanisms. Oxytocin is a neuropeptide which is involved in social bonding, trust, emotional responses and various social behaviors. By conducting passive avoidance and Morris water maze tests on male Wistar rats, the role of intraamygdaloid oxytocin in memory performance and learning was investigated. Oxytocin doses of 10 ng and 100 ng were injected into the central nucleus of the amygdala. Our results showed that 10 ng oxytocin significantly reduced the time required to locate the platform during the Morris water maze test while significantly increasing the latency time in the passive avoidance test. However, the 100 ng oxytocin experiment failed to produce a significant effect in either of the tests. Wistar rats pretreated with 20 ng oxytocin receptor antagonist (L-2540) were administered 10 ng of oxytocin into the central nucleus of the amygdala and were also subjected to the aforementioned tests to highlight the role of oxytocin receptors in spatial- and avoidance learning. Results suggest that oxytocin supports memory processing during both the passive avoidance and the Morris water maze tests. Oxytocin antagonists can however block the effects of oxytocin in both tests. The results substantiate that oxytocin uses oxytocin receptors to enhance memory and learning performance.


Assuntos
Ocitocina , Receptores de Ocitocina , Ratos , Animais , Masculino , Ratos Wistar , Ocitocina/farmacologia , Aprendizagem Espacial , Aprendizagem da Esquiva , Aprendizagem em Labirinto
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