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1.
Histochem Cell Biol ; 157(1): 107-118, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34738145

RESUMO

Amilenus aurantiacus overwinter in diapause, a natural starvation period, in hypogean habitats. The structure of spherites in the midgut diverticula (MD) and Malpighian tubules (MT) has been studied comparatively by light microscopy and TEM to detect eventual differences in mineral consumption in the beginning and at the end of the starvation period in these organs (MD and MT) associated with digestive processes. The chemical composition of spherites was examined by combining energy-dispersive X-ray spectroscopy (EDXS), electron energy-loss spectroscopy (EELS) and energy-filtered TEM (EFTEM). The structure of the spherites changed during overwintering in both organs. At the beginning of overwintering, the spherites were composed of densely packed concentric layers of electron-dense and electron-lucent material. In the middle and at the end of overwintering, the electron-lucent layers between the layers of material indicated the loss of some material. The chemical composition of the spherites changed only in the MD; at the beginning of overwintering, these contained Si, O, C and Fe, while later there was no more Fe. In contrast, spherites in the MT were composed of Si, O, C and Ca throughout overwintering. A less intensive exploitation of the MD spherites was probably due to complete cessation of digestive and other cell activity in this organ during the winter diapause; activity of the MT slowed, but continued removing the cell metabolites.


Assuntos
Diapausa , Divertículo , Animais , Sistema Digestório , Túbulos de Malpighi/ultraestrutura , Estações do Ano
2.
Molecules ; 25(21)2020 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-33126621

RESUMO

This study presents an investigation of the anticancer and antimicrobial ability of a combination of ginger and cannabis extracts in different ratios (1:1, 7:3 and 3:7). Extracts were obtained using various methods (Soxhlet extractions, cold macerations, ultrasonic extractions and supercritical fluid extractions). The antioxidant activity and the presence of total phenols were measured in the extracts, and the effect of the application extracts in various concentrations (c = 50, 20, 10, 5, 1, 0.1, 0.01 mg/mL) on cells was investigated. Higher values of antioxidants were measured at the ratio where ginger was predominant, which is reflected in a higher concentration of total phenols. Depending on the polyphenol content, the extracts were most effective when prepared supercritically and ultrasonically. However, with respect to cell response, the ratio was shown to have no effect on inhibiting cancer cell division. The minimum concentration required to inhibit cancer cell growth was found to be 1 mg/mL. High-performance liquid chromatography (HPLC) analysis also confirmed the effectiveness of ultrasonic and supercritical fluid extraction, as their extracts reached higher cannabinoid contents. In both extractions, the cannabidiol (CBD) content was above 30% and the cannabidiolic acid (CBDA) content was above 45%. In the case of ultrasonic extraction, a higher quantity of cannabigerol (CBG) (5.75 ± 0.18) was detected, and in the case of supercritical fluid extraction, higher cannabichromene (CBC) (5.48 ± 0.13) content was detected, when compared to other extraction methods. The antimicrobial potential of extracts prepared with ultrasonic and supercritical extractions on three microorganisms (Staphylococcus aureus, Escherichia coli and Candida albicans) was checked. Ginger and cannabis extract show better growth inhibition of microorganisms in cannabis-dominated ratios for gram-positive bacterium S. aureus, MIC = 9.38 mg/mL, for gram-negative bacterium E. coli, MIC > 37.5 mg/mL and for the C. albicans fungus MIC = 4.69 mg/mL. This suggests guidelines for further work: a 1: 1 ratio of ginger and hemp will be chosen in a combination with supercritical and ultrasonic extraction.


Assuntos
Anti-Infecciosos/farmacologia , Antineoplásicos/farmacologia , Cannabis/química , Extratos Vegetais/farmacologia , Zingiber officinale/química , Candida albicans/efeitos dos fármacos , Candida albicans/metabolismo , Linhagem Celular Tumoral , Escherichia coli/efeitos dos fármacos , Escherichia coli/metabolismo , Humanos , Metástase Neoplásica , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/metabolismo
3.
Cell Mol Biol (Noisy-le-grand) ; 64(11): 41-43, 2018 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-30213298

RESUMO

Dimethyl sulphoxide (DMSO) is widely used as a solvent in biomedical research, regularly in concentrations up to 1%. Nevertheless, little is known about the effect of different DMSO concentration on WM-266-4 metastatic melanoma cells, which are often used in melanoma research. Due to resistance of melanoma cells high concentrations of cytotoxic substances soluble in DMSO are used in vitro tests. Consequently, total DMSO concentration often exceeds 1%. The aim of our study was to test the metabolic activity and morphology of WM-266-4 cells exposed to selected DMSO concentrations for different period of time. Cells were incubated in selected ethanol concentrations for comparison. MTT test was performed to determine proliferation activity of the cells and morphological analysis was carried out by phase-contrast microscopy. Our results show inhibitory effect of DMSO on WM-266-4 cells' metabolic activity. Morphology of the cells changed progressively with the time of exposure. Ethanol showed little effect on metabolic activity of the cells and no effect on cell morphology after selected period of time. According to our study, for specific in vitro tests concentrations of DMSO up to 1.5% may be appropriate for WM-266-4 cell line experiments.


Assuntos
Dimetil Sulfóxido/farmacologia , Melanoma/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Microscopia de Contraste de Fase
4.
Front Cell Dev Biol ; 12: 1380564, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38550379

RESUMO

Mouse models of diet-induced type 2 diabetes mellitus provide powerful tools for studying the structural and physiological changes that are related to the disease progression. In this study, diabetic-like glucose dysregulation was induced in mice by feeding them a western diet, and light and transmission electron microscopy were used to study the ultrastructural changes in the pancreatic acinar cells. Acinar necrosis and vacuolization of the cytoplasm were the most prominent features. Furthermore, we observed intracellular and extracellular accumulation of lipid compounds in the form of lipid droplets, structural enlargement of the cisternae of the rough endoplasmic reticulum (RER), and altered mitochondrial morphology, with mitochondria lacking the typical organization of the inner membrane. Last, autophagic structures, i.e., autophagosomes, autolysosomes, and residual bodies, were abundant within the acinar cells of western diet-fed mice, and the autolysosomes contained lipids and material of varying electron density. While diets inducing obesity and type 2 diabetes are clearly associated with structural changes and dysfunction of the endocrine pancreas, we here demonstrate the strong effect of dietary intervention on the structure of acinar cells in the exocrine part of the organ before detectable changes in plasma amylase activity, which may help us better understand the development of non-alcoholic fatty pancreas disease and its association with endo- and exocrine dysfunction.

5.
Front Bioeng Biotechnol ; 10: 897185, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35620474

RESUMO

Arnica montana L. flower heads are known for their antioxidant, antimicrobial, and anticancer activity. The aim of this work was to optimize the process of supercritical CO2 extraction, to achieve high extraction yield and high content of biologically active components, and to confirm the antimicrobial and anticancer activity of the extract. The influence of pressure and temperature on the total phenolic content, antioxidant activity, and proanthocyanidin content was evaluated. The pressure and temperature were found to be interdependent. A temperature of 60°C and a pressure of 30 MPa resulted in a high extraction yield, antioxidant activity and phenolic content. The content of proanthocyanidins was highest at a pressure between 18 and 24 MPa. The extracts inhibited three different microorganisms successfully; Staphylococcus aureus, Escherichia coli and Candida albicans, at concentrations ranging from 0.1 to 5.16 mg/ml and showed anticancer activity decrease up to 85% at a concentration of 0.5 mg/ml.

6.
Arch Gynecol Obstet ; 281(2): 363-7, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19504115

RESUMO

PURPOSE: To determine the relationship between sperm morphological abnormalities, DNA fragmentation and fertilization rate in intracytoplasmic sperm injection (ICSI). METHODS: Sperm samples from 20 ICSI cycles were analysed. Morphology was assessed according to strict criteria, and DNA fragmentation was measured by terminal deoxynucleotidyl transferase (TdT)-mediated fluorescein-dUTP nick end labelling (TUNEL) using flow cytometry. RESULTS: A negative correlation was found between the percentage of spermatozoa with elongated heads and fertilization rate. There was a significant difference in the amount of morphological abnormalities between sperm samples with low and high degree of DNA fragmentation. The percentages of amorphous heads and overall head abnormalities were significantly higher in sperm samples with elevated degree of DNA fragmentation. No correlation was found between sperm DNA fragmentation and fertilization rate. CONCLUSIONS: Head abnormalities, especially amorphous heads, are related to elevated degree of DNA fragmentation. Elongated heads, when detected as predominant abnormal form in sperm samples, may affect fertilization in ICSI.


Assuntos
Dano ao DNA/fisiologia , Injeções de Esperma Intracitoplásmicas/normas , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/fisiologia , Adulto , Feminino , Humanos , Marcação In Situ das Extremidades Cortadas , Masculino , Pessoa de Meia-Idade , Gravidez , Cabeça do Espermatozoide/fisiologia , Espermatozoides/citologia , Estatísticas não Paramétricas
7.
Acta Pharm ; 70(1): 1-15, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31677369

RESUMO

Poly(3-hydroxybutyrate) is a natural polymer, produced by different bacteria, with good biocompatibility and biodegradability. Cardiovascular patches, scaffolds in tissue engineering and drug carriers are some of the possible biomedical applications of poly(3-hydroxybutyrate). In the past decade, many researchers examined the different physico-chemical modifications of poly(3-hydroxybutyrate) in order to improve its properties for use in the field of bone tissue engineering. Poly(3-hydroxybutyrate) composites with hydroxyapatite and bioglass are intensively tested with animal and human osteoblasts in vitro to provide information about their biocompatibility, biodegradability and osteoinductivity. Good bone regeneration was proven when poly(3-hydroxy-butyrate) patches were implanted in vivo in bone tissue of cats, minipigs and rats. This review summarizes the recent reports of in vitro and in vivo studies of pure poly(3-hydroxy-butyrate) and poly(3-hydroxybutyrate) composites with the emphasis on their bioactivity and biocompatibility with bone cells.


Assuntos
Osso e Ossos/metabolismo , Hidroxibutiratos/química , Poliésteres/química , Engenharia Tecidual/métodos , Animais , Regeneração Óssea , Gatos , Humanos , Osteoblastos/metabolismo , Ratos , Suínos , Porco Miniatura , Alicerces Teciduais/química
8.
Bosn J Basic Med Sci ; 19(1): 14-23, 2019 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-30172249

RESUMO

The plant Cannabis sativa L. has been used as an herbal remedy for centuries and is the most important source of phytocannabinoids. The endocannabinoid system (ECS) consists of receptors, endogenous ligands (endocannabinoids) and metabolizing enzymes, and plays an important role in different physiological and pathological processes. Phytocannabinoids and synthetic cannabinoids can interact with the components of ECS or other cellular pathways and thus affect the development/progression of diseases, including cancer. In cancer patients, cannabinoids have primarily been used as a part of palliative care to alleviate pain, relieve nausea and stimulate appetite. In addition, numerous cell culture and animal studies showed antitumor effects of cannabinoids in various cancer types. Here we reviewed the literature on anticancer effects of plant-derived and synthetic cannabinoids, to better understand their mechanisms of action and role in cancer treatment. We also reviewed the current legislative updates on the use of cannabinoids for medical and therapeutic purposes, primarily in the EU countries. In vitro and in vivo cancer models show that cannabinoids can effectively modulate tumor growth, however, the antitumor effects appear to be largely dependent on cancer type and drug dose/concentration. Understanding how cannabinoids are able to regulate essential cellular processes involved in tumorigenesis, such as progression through the cell cycle, cell proliferation and cell death, as well as the interactions between cannabinoids and the immune system, are crucial for improving existing and developing new therapeutic approaches for cancer patients. The national legislation of the EU Member States defines the legal boundaries of permissible use of cannabinoids for medical and therapeutic purposes, however, these legislative guidelines may not be aligned with the current scientific knowledge.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Canabinoides/uso terapêutico , Legislação de Medicamentos , Neoplasias/tratamento farmacológico , Animais , Cannabis/química , Humanos
9.
G Ital Dermatol Venereol ; 154(2): 197-204, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28704989

RESUMO

BACKGROUND: Octocrylene (OCT) is one of the most widespread chemical UV filters used in sunscreens and cosmetic products. Despite the use of sunscreens and personal care products over decades, melanoma as the most serious and aggressive form of skin cancer is still a cause of concern. Hence the aim of this study was to investigate any potential influence of OCT on metabolic activity, cytotoxicity and ABCB5 mRNA expression in melanoma cells. The ABCB5 transmembrane protein was tested due to its well-known role in the initiation, invasion and metastatic spread of various cancers, including melanoma. METHODS: Metastatic melanoma cell line WM-266-4 (ATCC) was incubated with selected concentrations of OCT and for different time intervals. The MTT and LDH assays to measure the cells' metabolic activity and cytotoxicity were used respectively. Target gene (ABCB5) expression was detected by quantitative real-time PCR (qRT-PCR), using TaqMan® chemistry. RESULTS: Our results suggest decreased metastatic melanoma cells' metabolic activity, increased cytotoxicity and increased ABCB5 mRNA expression (P<0.05) with longer time of exposure to OCT as compared to control cells. Accordingly, we suspect that the surviving cells are more invasive and aggressive, which might explain their microscopically observed cannibalistic activity. CONCLUSIONS: With this study, we elucidate a new promising field for further research to contribute to etiology and prevention of melanoma.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Acrilatos/farmacologia , Melanoma/tratamento farmacológico , Neoplasias Cutâneas/tratamento farmacológico , Subfamília B de Transportador de Cassetes de Ligação de ATP , Acrilatos/administração & dosagem , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Melanoma/genética , Melanoma/patologia , Metástase Neoplásica , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia , Protetores Solares/administração & dosagem , Protetores Solares/farmacologia , Fatores de Tempo
10.
Sci Rep ; 9(1): 9121, 2019 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-31235705

RESUMO

The European cave spider, Meta menardi, is a representative of the troglophiles, i.e. non-strictly subterranean organisms. Our aim was to interpret the cytological results from an ecological perspective, and provide a synthesis of the hitherto knowledge about M. menardi into a theory of key features marking it a troglophile. We studied ultrastructural changes of the midgut epithelial cells in individuals spending winter under natural conditions in caves, using light microscopy and TEM. The midgut diverticula epithelium consisted of secretory cells, digestive cells and adipocytes. During winter, gradual vacuolization of some digestive cells appeared, and some necrotic digestive cells and necrotic adipocytes appeared. This cytological information completes previous studies on M. menardi starved under controlled conditions in the laboratory. In experimental starvation and natural winter conditions, M. menardi gradually exploit reserve compounds from spherites, protein granules and through autophagy, and energy-supplying lipids and glycogen, as do many overwintering arthropods. We found no special cellular response to living in the habitat. Features that make it partly adapted to the subterranean habitat include starvation hardiness as a possible preadaptation, an extremely opportunistic diet, a partly reduced orb, tracking and capturing prey on bare walls and partly reduced tolerance to below-zero temperatures.


Assuntos
Adaptação Fisiológica , Ecossistema , Aranhas/fisiologia , Aclimatação , Animais , Feminino , Masculino , Estações do Ano
11.
Cell Biol Int ; 32(7): 777-83, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18440247

RESUMO

The distribution of cytosolic fibroblast growth factor receptor 1 (FGFR1) was studied in correlation to cell migration in urothelial cell line g/G. Cell motility was analysed with a new method using consecutive series of photographs of cells relocated on CELLocate coverslips and with image analysis software. The results confirmed that FGF1 stimulated cell motility only when cells were grown on collagen I coating. During the transition from sessile to motile cell phenotype a complete redistribution of cytosolic FGFR1 was revealed. In sessile cells, FGFR1 had a filamentous distribution and its location matched cytokeratin 7. In cells of the migrating phenotype, the distribution of FGFR1 was diffuse, mainly located in cytosol. Our data reveal that the location of cytosolic FGFR1 depends on the motile characteristics of the cell. The results also indicate that attachment of cells to collagen I is crucial for the induction of urothelial cell motility with FGF1.


Assuntos
Movimento Celular , Citosol/metabolismo , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/metabolismo , Urotélio/citologia , Citoesqueleto de Actina/metabolismo , Animais , Linhagem Celular , Colágeno/metabolismo , Citoesqueleto/metabolismo , Camundongos , Urotélio/metabolismo
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