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1.
Cerebellum ; 17(4): 461-464, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29488162

RESUMO

Vincenzo Malacarne, professor of medicine, surgery, and obstetrics in Turin, Pavia, and Padua, Italy, represented a perfect example of an eighteenth century "letterato", combining interests in humanities, sciences, and politics, embodying the ideal of an encyclopedic and universal culture. He made important contributions in anatomy and surgery, teratology, obstetrics, neurology, and history of medicine, adopting a interdisciplinary approach based on the correlation between anatomy, surgery, and clinics. He deserves a special place in the history of neurology because of the first complete description of the human cerebellum. He quantified the units of the cerebellar internal structures, the lamellae being numbered for a systematic description of the human cerebellum. He thought the mental faculties depended on their number, considering a relation between the number of cerebellar lamellae and the expression of intellectual faculties. In this way, he made first statistics on human faculties. He advanced the concept that the number of cerebellar folia was influenced by the environment, thus providing the first nature-nurture hypothesis made on the basis of observations, and the concept of neuroplasticity in the scientific literature. Finally, he also contributed to the emergence of a new science, namely electrophysiology, because he laid down experimental foundations of a project on the recording of brain electricity, comparing the structure of the human brain with Volta's galvanic pillar.


Assuntos
Cerebelo/anatomia & histologia , Neuroanatomia/história , Animais , Cerebelo/fisiologia , História do Século XVIII , História do Século XIX , Humanos , Itália
2.
Connect Tissue Res ; 59(6): 561-573, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29316809

RESUMO

PURPOSES: Incomplete tendon healing impairs the outcome of tendon ruptures and tendinopathies. Human Adipose-derived Stem Cells (hASCs) are promising for tissue engineering applications. Extracorporeal Shock Waves (ESW) are a leading choice for the treatment of several tendinopathies. In this study, we investigated the effects of ESW treatment and tenogenic medium on the differentiation of hASCs into tenoblast-like cells. MATERIALS AND METHODS: hASCs were treated with ESW generated by a piezoelectric device and tenogenic medium. Quantitative real-time PCR was used to check the mRNA expression levels of tenogenic transcription factors, extracellular matrix proteins, and integrins. Western blot and immunofluorescence were used to detect collagen 1 and fibronectin. Collagen fibers were evaluated by Masson staining. Calcium deposition was assessed by Alizarin Red staining. RESULTS: The combined treatment improved the expression of the tendon transcription factors scleraxis and eyes absent 2, and of the extracellular matrix proteins fibronectin, collagen I, and tenomodulin. Cells acquired elongated and spindle shaped fibroblastic morphology; Masson staining revealed the appearance of collagen fibers. Finally, the combined treatment induced the expression of alpha 2, alpha 6, and beta 1 integrin subunits, suggesting a possible role in mediating ESW effects. CONCLUSIONS: ESW in combination with tenogenic medium improved the differentiation of hASCs toward tenoblast-like cells, providing the basis for ESW and hASCs to be used in tendon tissue engineering.


Assuntos
Tecido Adiposo/metabolismo , Diferenciação Celular , Tratamento por Ondas de Choque Extracorpóreas , Células-Tronco/metabolismo , Tendinopatia , Ondas Ultrassônicas , Tecido Adiposo/patologia , Adulto , Antígenos de Diferenciação/biossíntese , Colágeno/metabolismo , Meios de Cultura/química , Meios de Cultura/farmacologia , Matriz Extracelular/metabolismo , Feminino , Regulação da Expressão Gênica , Humanos , Pessoa de Meia-Idade , Células-Tronco/patologia , Tendinopatia/metabolismo , Tendinopatia/patologia , Tendinopatia/terapia
3.
G Ital Med Lav Ergon ; 33(3 Suppl): 452-4, 2011.
Artigo em Italiano | MEDLINE | ID: mdl-23393897

RESUMO

In the last twenty years of the nineteenth century in Italy, the scientific bases are set in order to give birth to industrial/physical medicine. Physiology, hygiene and pathology deal with topics/matters/subjects bound to the working environment. Angelo Mosso deepens the studies, already begun in the 70s by Ugo Kronaker in Leipzig, about muscular strain by publishing these researches with two different purposes. The scientific and the popular one. The book La fatica, written in 1891, gathers the results of the researches on the muscular fatigue, examined from the physiological and psychological point of view, as strain caused by the continuous and close attention. A scientific treatise that builds the foundation of modern ergonomic. Mosso then considers the physical effects of fatigue coming up to the extreme cases of some groups of workers, such as those engaged in the extraction of sulfur in Sicily, through the acceptance of more and more miserable wages, compelled by necessity, they are forced to work in inhuman conditions. This downward work offer is defined by Mosso as ergomachia. This struggle leads after short time the worker to exhaustion of strength, untill reaching a severe, permanent and irriversible debilitation. Forces the worker, until anyone reach a state of severe pathological physical debilitation permanent and irreversible.


Assuntos
Medicina do Trabalho/história , História do Século XIX , Humanos , Itália
4.
Acta Diabetol ; 56(12): 1283-1292, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31407113

RESUMO

AIMS: Subcutaneous administration of insulin in patients suffering from diabetes is associated with the distress of daily injections. Among alternative administration routes, the oral route seems to be the most advantageous for long-term administration, also because the peptide undergoes a hepatic first-pass effect, contributing to the inhibition of the hepatic glucose output. Unfortunately, insulin oral administration has so far been hampered by degradation by gastrointestinal enzymes and poor intestinal absorption. Loading in lipid nanoparticles should allow to overcome these limitations. METHODS: Entrapment of peptides into such nanoparticles is not easy, because of their high molecular weight, hydrophilicity and thermo-sensitivity. In this study, this objective was achieved by employing fatty acid coacervation method: solid lipid nanoparticles and newly engineered nanostructured lipid carriers were formulated. Insulin and insulin analog-glargine insulin-were entrapped in the lipid matrix through hydrophobic ion pairing. RESULTS: Bioactivity of lipid entrapped peptides was demonstrated through a suitable in vivo experiment. Ex vivo and in vivo studies were carried out by employing fluorescently labelled peptides. Gut tied up experiments showed the superiority of glargine insulin-loaded nanostructured lipid carriers, which demonstrated significantly higher permeation (till 30% dose/mL) compared to free peptide. Approximately 6% absolute bioavailability in the bloodstream was estimated for the same formulation through in vivo pharmacokinetic studies in rats. Consequently, a discrete blood glucose responsivity was noted in healthy animals. CONCLUSIONS: Given the optimized ex vivo and in vivo intestinal uptake of glargine insulin from nanostructured lipid carriers, further studies will be carried out on healthy and diabetic rat models in order to establish a glargine insulin dose-glucose response relation.


Assuntos
Portadores de Fármacos , Insulina/administração & dosagem , Lipídeos , Nanopartículas , Administração Oral , Animais , Células Cultivadas , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Liberação Controlada de Fármacos , Humanos , Insulina/análogos & derivados , Insulina/farmacocinética , Insulina Glargina/administração & dosagem , Insulina Glargina/análogos & derivados , Insulina Glargina/farmacocinética , Lipídeos/administração & dosagem , Lipídeos/química , Lipídeos/farmacocinética , Masculino , Nanopartículas/administração & dosagem , Nanopartículas/química , Nanopartículas/metabolismo , Técnicas de Cultura de Órgãos , Tamanho da Partícula , Ratos , Ratos Wistar
5.
J Nanosci Nanotechnol ; 6(9-10): 3062-9, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17048519

RESUMO

The structure of both carrier and anticancer drug affects the intracellular fate of a transported drug. The study investigated in vitro intracellular accumulation and cytotoxic activity of doxorubicin-loaded solid lipid nanoparticles (SLN), doxorubicin in pegylated liposomes (Caelyx) and free doxorubicin. Intracellular doxorubicin levels and cytotoxic activity were determined by high performance liquid chromatography with fluorescence detection, and by the trypan blue dye exclusion assay, respectively. Doxorubicin-loaded SLN inhibited cell growth more strongly than either free or liposomal doxorubicin, in human colorectal adenocarcinoma, HT-29, retinoblastoma Y79, and glioblastoma U373 cell lines. The IC50 values for doxorubicin-loaded SLN were significantly lower after 24 h exposure than those for free doxorubicin in all cell lines; after 48 h exposure they were lower than those for liposomal doxorubicin in HT-29 and Y79 cells. The enhanced cytotoxic activity of doxorubicin-loaded SLN was associated with increased drug incorporation in cells: intracellular doxorubicin levels were significantly enhanced after exposure to drug-loaded SLN versus either free or liposomal drug. Rate of intracellular accumulation and cytotoxic activity also differed among different cell lines; in particular, cells of epithelial origin were found to be more sensitive to doxorubicin-loaded SLN. In conclusion, the greater sensitivity of HT-29, Y79, and U373 cells to doxorubicin-loaded SLN than to the other drug formulations may be due to the capability of the delivery system to enhance drug action, through a marked uptake and accumulation of SLN within the cell.


Assuntos
Doxorrubicina/administração & dosagem , Doxorrubicina/farmacocinética , Portadores de Fármacos/química , Lipossomos/química , Neoplasias/metabolismo , Neoplasias/patologia , Polietilenoglicóis/química , Antibióticos Antineoplásicos/administração & dosagem , Antibióticos Antineoplásicos/farmacocinética , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Líquido Intracelular/metabolismo , Nanoestruturas/química , Nanoestruturas/ultraestrutura
6.
J Drug Target ; 10(4): 327-35, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12164381

RESUMO

The pharmacokinetics and tissue distribution of doxorubicin incorporated in non-stealth solid lipid nanoparticles (SLN) and in stealth solid lipid nanoparticles (SSLN) (three formulations at increasing concentrations of stearic acid-PEG 2000 as stealth agent) after intravenous administration to conscious rabbits have been studied. The control was the commercial doxorubicin solution. The experiments lasted 6 h and blood samples were collected at fixed times after the injections. In all samples, the concentration of doxorubicin and doxorubicinol were determined. Doxorubicin AUC increased as a function of the amount of stealth agent present in the SLN. Doxorubicin was still present in the blood 6 h after the injection of SLN or SSLN, while no doxorubicin was detectable after the i.v. injection of doxorubicin solution. Tissue distribution of doxorubicin was determined 30 min, 2 and 6 h after the administration of the five formulations. Doxorubicin was present in the brain only after the SLN administration. The increase in the stealth agent affected the doxorubicin transported into the brain; 6 h after injection, doxorubicin was detectable in the brain only with the SSLN at the highest amount of stealth agent. In the other rabbit tissues (liver, lungs, spleeen, heart and kidneys) the amount of doxorubicin present was always lower after the injection of any of the four types of SLN than after the commercial solution. In particular, all SLN formulations significantly decreased heart and liver concentrations of doxorubicin.


Assuntos
Encéfalo/efeitos dos fármacos , Doxorrubicina/administração & dosagem , Portadores de Fármacos/administração & dosagem , Nanotecnologia/métodos , Animais , Encéfalo/metabolismo , Química Farmacêutica , Doxorrubicina/sangue , Doxorrubicina/farmacocinética , Portadores de Fármacos/farmacocinética , Injeções Intravenosas , Microesferas , Coelhos , Distribuição Tecidual/efeitos dos fármacos , Distribuição Tecidual/fisiologia
7.
J Pharm Sci ; 91(5): 1324-33, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-11977108

RESUMO

Idarubicin-loaded solid lipid nanoparticles (IDA-SLN) and idarubicin in solution were prepared and the two formulations were administered to rats, either by the duodenal route or intravenously (iv). The aim of this research was to study whether the bioavailability of idarubicin can be improved by administering IDA-SLN duodenally to rats. Idarubicin and its main metabolite idarubicinol were determined in plasma and tissues by reversed-phase high-performance liquid chromatography. The pharmacokinetic parameters of idarubicin found after duodenal administration of the two formulations were different: area under the curve of concentration versus time (AUC) and elimination half-life were approximately 21 times and 30 times, respectively, higher after IDA-SLN administration than after the solution administration. Tissue distribution also differed: idarubicin and idarubicinol concentrations were lower in heart, lung, spleen, and kidneys after IDA-SLN administration than after solution administration. The drug and its metabolite were detected in the brain only after IDA-SLN administration, indicating that SLN were able to pass the blood-brain barrier. After iv IDA-SLN administration, the AUC of idarubicin was lower than after duodenal administration of the same formulation. Duodenal administration of IDA-SLN modifies the pharmacokinetics and tissue distribution of idarubicin. The IDA-SLN act as a prolonged release system for the drug.


Assuntos
Antibióticos Antineoplásicos/farmacocinética , Daunorrubicina/análogos & derivados , Idarubicina/farmacocinética , Animais , Antibióticos Antineoplásicos/administração & dosagem , Daunorrubicina/sangue , Vias de Administração de Medicamentos , Portadores de Fármacos , Duodeno , Idarubicina/administração & dosagem , Nanotecnologia , Ratos , Ratos Wistar , Soluções , Distribuição Tecidual
8.
J Pharm Sci ; 92(5): 1085-94, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12712429

RESUMO

Three types of solid lipid nanoparticles (SLN) containing three different percentages of tobramycin (1.25, 2.50, 5.00%) were prepared (Tobra-SLN), and the in vitro tobramycin diffusion through a hydrophilic/lipophilic membrane was determined. A variable quantity of each of the three SLN types was placed in the donor compartment to achieve the same amount of tobramycin in each case. Tobramycin diffusion varied with the percentage of drug incorporated in SLN: the higher the percentage of tobramycin incorporated, the greater the amount of the drug diffused. In vivo uptake and transport were determined after administering a fixed dose of tobramycin (5 mg/kg) in each of the three types of SLN intraduodenally to rats. At fixed times, blood was sampled from the jugular vein and lymph from the thoracic duct. Lymph and blood were examined by transmission electron microscopy (TEM) analysis to detect the presence, sizes, and shape of SLN. The pharmacokinetic parameters varied considerably with the type of Tobra-SLN: the area under the curve of plasma concentration versus time (AUC) of 1.25% Tobra-SLN was more than five times higher than that of 5.00% Tobra-SLN; the longest residence time was obtained with 1.25% Tobra-SLN; and the clearance of 5.00% Tobra-SLN was fivefold than that of 1.25% Tobra-SLN. This behavior may be related to the differences among the three types of SLN; namely, the number of SLN administered and the mean diameter, the total surface area, and the drug content in each nanoparticle. TEM analysis showed that Tobra-SLNs were targeted to the lymph. Tobra-SLN may act as a reservoir of the drug in the lymphatic system, thereby favoring its sustained release.


Assuntos
Antibacterianos/metabolismo , Duodeno/metabolismo , Tobramicina/metabolismo , Absorção , Animais , Antibacterianos/administração & dosagem , Antibacterianos/sangue , Preparações de Ação Retardada , Difusão , Sistemas de Liberação de Medicamentos , Emulsões , Técnicas In Vitro , Lipídeos/administração & dosagem , Linfa/metabolismo , Linfonodos/metabolismo , Masculino , Microscopia Eletrônica , Nanotecnologia , Tamanho da Partícula , Ratos , Ratos Wistar , Fatores de Tempo , Tobramicina/administração & dosagem , Tobramicina/sangue
9.
J Microencapsul ; 24(7): 660-72, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17763060

RESUMO

Insulin-loaded solid lipid nanoparticles (SLN), obtained by the solvent-in-water emulsion-diffusion technique, were produced using isovaleric acid (IVA) as organic phase, glyceryl mono-stearate (GMS) as lipid, soy lecithin and sodium taurodeoxycholate (TDC) as emulsifiers. IVA, a partially water-miscible solvent with low toxicity, was used to dissolve both insulin and lipids. SLN of spherical shape were obtained by simple water dilution of the O/W emulsion. Analysis of SLN content after processing showed interesting encapsulation efficiency with respect to therapeutic doses; moreover, insulin did not undergo any chemical modification within the nanoparticles and most of it remained stable after incubation of the SLN with trypsin solution. The biological activity of insulin, i.e. the ability to decrease glycemia in rats, was not negatively influenced by the SLN production process, as after subcutaneous administration of insulin extracted from SLN to animals, the blood glucose levels were quite similar to those obtained after administration of a conventional insulin suspension. Consequently, SLN seem to have interesting possibilities as delivery systems for oral administration of insulin.


Assuntos
Insulina/química , Lipídeos/química , Nanopartículas/química , Água/química , Administração Oral , Animais , Varredura Diferencial de Calorimetria/métodos , Bovinos , Cromatografia Líquida de Alta Pressão , Difusão , Concentração de Íons de Hidrogênio , Insulina/administração & dosagem , Insulina/metabolismo , Ratos , Solventes/química , Temperatura , Fatores de Tempo
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