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1.
Rev. méd. Chile ; 150(12): 1555-1564, dic. 2022. tab, graf
Artículo en Español | LILACS | ID: biblio-1515396

RESUMEN

BACKGROUND: Alcohol and tobacco are important risk factors for chronic pancreatitis (CP). AIM: To analyze the effect of etiological factors such as tobacco and alcohol and pancreatic enzyme replacement therapy (PERT) in the progression of CP. MATERIAL AND METHODS: Patients with a diagnosis of CP were recruited and grouped according to variables such as tobacco, alcohol and PERT. They were followed for 18 months. Subsequently, different variables and analytical parameters involved in the progression of the disease were analyzed. RESULTS: A total of 50 patients diagnosed with CP were included. Of these, 28 patients underwent PERT, 39 were smokers and 33 were alcohol users. Compared with patients without PERT, those with PERT had a higher proportion of diabetes (64 and 32%, respectively), had a higher need for endoscopic treatment (25 and 0%, respectively) and a normal body mass index (71 and 27.3%, respectively. The smokers had higher calcium levels and increased lymphocytosis and leukocytosis. The alcohol consumption group had a higher mean age (p = 0.04) CONCLUSIONS: PERT may improve the nutritional status but does not reduce the need for endoscopic or surgical treatment. Smoking and alcohol consumption favored the progression of CP. Also, smoking induced a pro-inflammatory state.


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Anciano , Pancreatitis Crónica/etiología , Pancreatitis Crónica/terapia , Pancreatitis Crónica/epidemiología , Páncreas , Insuficiencia Pancreática Exocrina/etiología , Insuficiencia Pancreática Exocrina/terapia , Nicotiana/efectos adversos , Consumo de Bebidas Alcohólicas/efectos adversos , Factores de Riesgo , Distribución por Sexo , Progresión de la Enfermedad , Terapia Enzimática
2.
Rev Med Chil ; 150(12): 1555-1564, 2022 Dec.
Artículo en Español | MEDLINE | ID: mdl-37906776

RESUMEN

BACKGROUND: Alcohol and tobacco are important risk factors for chronic pancreatitis (CP). AIM: To analyze the effect of etiological factors such as tobacco and alcohol and pancreatic enzyme replacement therapy (PERT) in the progression of CP. MATERIAL AND METHODS: Patients with a diagnosis of CP were recruited and grouped according to variables such as tobacco, alcohol and PERT. They were followed for 18 months. Subsequently, different variables and analytical parameters involved in the progression of the disease were analyzed. RESULTS: A total of 50 patients diagnosed with CP were included. Of these, 28 patients underwent PERT, 39 were smokers and 33 were alcohol users. Compared with patients without PERT, those with PERT had a higher proportion of diabetes (64 and 32%, respectively), had a higher need for endoscopic treatment (25 and 0%, respectively) and a normal body mass index (71 and 27.3%, respectively. The smokers had higher calcium levels and increased lymphocytosis and leukocytosis. The alcohol consumption group had a higher mean age (p = 0.04) Conclusions: PERT may improve the nutritional status but does not reduce the need for endoscopic or surgical treatment. Smoking and alcohol consumption favored the progression of CP. Also, smoking induced a pro-inflammatory state.


Asunto(s)
Insuficiencia Pancreática Exocrina , Pancreatitis Crónica , Humanos , Insuficiencia Pancreática Exocrina/etiología , Insuficiencia Pancreática Exocrina/terapia , Pancreatitis Crónica/epidemiología , Pancreatitis Crónica/etiología , Pancreatitis Crónica/terapia , Páncreas , Factores de Riesgo , Progresión de la Enfermedad
3.
Polymers (Basel) ; 12(12)2020 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-33255803

RESUMEN

A reproducible and efficient interfacial polymer disposition method has been used to formulate magnetite/poly(ε-caprolactone) (core/shell) nanoparticles (average size ≈ 125 nm, production performance ≈ 90%). To demonstrate that the iron oxide nuclei were satisfactorily embedded within the polymeric solid matrix, a complete analysis of these nanocomposites by, e.g., electron microscopy visualizations, energy dispersive X-ray spectroscopy, Fourier-transform infrared spectroscopy, electrophoresis, and contact angle goniometry was conducted. The magnetic responsive behaviour of these nanoparticles was quantitatively characterized by the hysteresis cycle and qualitatively investigated by visualization of the colloid under exposure to a 0.4 T magnet. Gemcitabine entrapment into the polymeric shell reported adequate drug loading values (≈11%), and a biphasic and pH-responsive drug release profile (≈ four-fold faster Gemcitabine release at pH 5.0 compared to pH 7.4). Cytotoxicity studies in MCF-7 human breast cancer cells proved that the half maximal inhibitory concentration of Gem-loaded nanocomposites was ≈ two-fold less than that of the free drug. Therefore, these core/shell nanoparticles could have great possibilities as a magnetically targeted Gemcitabine delivery system for breast cancer treatment.

4.
IEEE J Biomed Health Inform ; 24(7): 2119-2130, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-31871000

RESUMEN

Many clinical studies have revealed the high biological similarities existing among different skin pathological states. These similarities create difficulties in the efficient diagnosis of skin cancer, and encourage to study and design new intelligent clinical decision support systems. In this sense, gene expression analysis can help find differentially expressed genes (DEGs) simultaneously discerning multiple skin pathological states in a single test. The integration of multiple heterogeneous transcriptomic datasets requires different pipeline stages to be properly designed: from suitable batch merging and efficient biomarker selection to automated classification assessment. This article presents a novel approach addressing all these technical issues, with the intention of providing new sights about skin cancer diagnosis. Although new future efforts will have to be made in the search for better biomarkers recognizing specific skin pathological states, our study found a panel of 8 highly relevant multiclass DEGs for discerning up to 10 skin pathological states: 2 healthy skin conditions a priori, 2 cataloged precancerous skin diseases and 6 cancerous skin states. Their power of diagnosis over new samples was widely tested by previously well-trained classification models. Robust performance metrics such as overall and mean multiclass F1-score outperformed recognition rates of 94% and 80%, respectively. Clinicians should give special attention to highlighted multiclass DEGs that have high gene expression changes present among them, and understand their biological relationship to different skin pathological states.


Asunto(s)
Diagnóstico por Computador/métodos , Perfilación de la Expresión Génica/métodos , Aprendizaje Automático , RNA-Seq/métodos , Neoplasias Cutáneas/diagnóstico , Biomarcadores de Tumor/análisis , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Biología Computacional , Humanos , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/metabolismo
5.
Oncotarget ; 9(23): 16573-16587, 2018 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-29662668

RESUMEN

Pancreatic cancer (PC) is a highly malignant disease that represents the fourth leading cancer-related death worldwide. There has been very little improvement in survival rates over recent years, and surgical resection remains the only reliable curative approach. Factors that contribute to this dismal prognosis for PC include its rapid progression and invasion, the absence of specific symptoms, and the little impact of available chemotherapy. Importantly, the management of this malignancy is also limited by the lack of highly specific and sensitive biomarkers for its diagnosis and follow-up, and their identification is therefore considered a promising strategy to improve outcomes in these patients. Numerous translational studies have explored the usefulness of body fluids as a non-invasive source of PC-specific biomarkers, and innovations in proteomic methods and technologies have provided a myriad of protein biomarkers for different cancers. The adoption of a proteomic approach has improved understanding of the biology of PC and contributed to the potential identification of protein biomarkers for this disease. This review considers the most recent research efforts to develop novel proteomic biomarkers in body fluids for PC.

6.
Anticancer Agents Med Chem ; 18(6): 847-853, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29332602

RESUMEN

BACKGROUND: Triterpenoids are an important class of natural bioactive products present in many medicinal plants. OBJECTIVE: The aim of present study is to investigate the antioxidant and anticarcinogenic potential of Oleanolic Acid (OA) and Ursolic Acid (UA) on B16 murine melanoma cell line isolated from Plumeria obtusa, free and loaded in a nanoemulsion (NEm) system. METHODS: The nanoemulsion was characterized by dynamic light scattering, transmission electron microscopy. The viscosity was also evaluated. The antioxidant activity was determined by the reduction of 2,2-diphenyl-2- picrylhydrazyl (DPPH) free radical. In vitro proliferation studies were determined using the sulforhodamine-B method. RESULTS: OA/UA natural mixture exhibited high percentage of inhibition of DPPH (86.06% and 85.12%, with and without irradiation). Percentages of inhibition higher than 85% in samples with and without ultraviolet irradiation were recorded when loaded in the NEm system. The natural mixture incorporated into the NEm showed cytotoxic activity from 2.9 µM, whereas the free compounds from 17.4 µM. CONCLUSION: We conclude that these pentacyclic triterpenes loaded in a NEm system could be considered as a new potential tool for further investigation as anticancer agents.


Asunto(s)
Antioxidantes/farmacología , Apocynaceae/química , Melanoma/tratamiento farmacológico , Nanopartículas/química , Ácido Oleanólico/farmacología , Triterpenos/farmacología , Animales , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Emulsiones/química , Emulsiones/aislamiento & purificación , Emulsiones/farmacología , Melanoma/patología , Ratones , Conformación Molecular , Ácido Oleanólico/química , Ácido Oleanólico/aislamiento & purificación , Relación Estructura-Actividad , Triterpenos/química , Triterpenos/aislamiento & purificación
7.
J Pharm Pharmacol ; 70(4): 488-497, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29380384

RESUMEN

OBJECTIVES: Liposomes have attracted the attention of researchers due to their potential to act as drug delivery systems for cancer treatment. The present investigation aimed to develop liposomes loaded with prednisolone base and the evaluation of the antiproliferative effect on human colon carcinoma cell lines. METHODS: Liposomes were elaborated by following a reproducible thin film hydration technique. The physicochemical characterization of liposomes included photon correlation spectroscopy, microscopy analysis, Fourier transform infrared spectroscopy, rheological behaviour and electrophoresis. On the basis of these data and drug loading values, the best formulation was selected. Stability and drug release properties were also tested. KEY FINDINGS: Resulting liposomes exhibited optimal physicochemical and stability properties, an excellent haemocompatibility and direct antiproliferative effect on human colon carcinoma T-84 cell lines. CONCLUSIONS: This study shows direct antitumour effect of prednisolone liposomal formulation, which opens the door for liposomal glucocorticoids as novel antitumour agents.


Asunto(s)
Antineoplásicos Hormonales/toxicidad , Neoplasias del Colon , Citotoxinas/toxicidad , Nanotecnología/métodos , Prednisolona/toxicidad , Antineoplásicos Hormonales/química , Antineoplásicos Hormonales/farmacocinética , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Proliferación Celular/fisiología , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Colon/patología , Citotoxinas/química , Citotoxinas/farmacocinética , Relación Dosis-Respuesta a Droga , Evaluación Preclínica de Medicamentos/métodos , Liberación de Fármacos/fisiología , Humanos , Liposomas , Prednisolona/química , Prednisolona/farmacocinética
8.
Int J Pharm ; 516(1-2): 61-70, 2017 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-27825867

RESUMEN

5-Fluorouracil (5-FU) is a broad spectrum cytotoxic agent being used in chemotherapy of malignancies. However, 5-FU shows a number of limitations like short half-life, non-selective biodistribution, and the development of drug resistances by tumour cells. It was investigated the potential use of folic acid-decorated and PEGylated poly(D,L-lactide-co-glycolide) nanoparticles (FOL-PEG-PLGA NPs) for the targeted delivery of 5-FU to colon and breast cancers. PEG-PLGA and FOL-PEG-PLGA conjugates were synthesized and characterized. NPs of PLGA, PEG-PLGA, and FOL-PEG-PLGA were prepared by nanoprecipitation under optimal formulation conditions. They were found to be haemocompatible, and exhibited negligible cytotoxicity in normal (CCD-18 and MCF-10A) and tumour (HT-29 and MCF-7) human cell lines. 5-FU loading capabilities were also defined, and the NPs exhibited an initial burst drug release followed by a sustained 5-FU release. In vitro cytotoxicity studies in folate-overexpressed HT-29 colon cancer cells and MCF-7 breast cancer cells demonstrated that the half maximal inhibitory concentration (IC50) of 5-FU-loaded FOL-PEG-PLGA NPs was approximately 4-fold less than that of the 5-FU-loaded PLGA NPs (p<0.05). Consequently, FOL-PEG-PLGA NPs could have great potential as a targeted 5-FU delivery system for colon and breast cancer treatment.


Asunto(s)
Sistemas de Liberación de Medicamentos , Fluorouracilo/administración & dosificación , Ácido Fólico/administración & dosificación , Nanopartículas , Antineoplásicos/administración & dosificación , Antineoplásicos/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Línea Celular , Química Farmacéutica/métodos , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Colon/patología , Portadores de Fármacos/química , Femenino , Fluorouracilo/farmacología , Ácido Fólico/farmacología , Células HT29 , Humanos , Concentración 50 Inhibidora , Células MCF-7 , Poliésteres/química , Polietilenglicoles/química , Distribución Tisular
9.
Int J Pharm ; 504(1-2): 11-9, 2016 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-26969080

RESUMEN

A reproducible double emulsion/solvent evaporation procedure is developed to formulate magnetic solid lipid nanoparticles (average size≈180 nm) made of iron oxide cores embedded within a glyceryl trimyristate solid matrix. The physicochemical characterization of the nanocomposites ascertained the efficacy of the preparation conditions in their production, i.e. surface properties (electrokinetic and thermodynamic data) were almost indistinguishable from those of the solid lipid nanomatrix, while electron microscopy characterizations and X-ray diffraction patterns confirmed the satisfactory coverage of the magnetite nuclei. Hemocompatibility of the particles was established in vitro. Hysteresis cycle determinations defined the appropriate magnetic responsiveness of the nanocomposites, and their heating characteristics were investigated in a high frequency alternating gradient of magnetic field: a constant maximum temperature of 46 °C was obtained within 40 min. Finally, in vitro tests performed on human HT29 colon adenocarcinoma cells demonstrated a promising decrease in cell viability after treatment with the nanocomposites and exposure to that alternating electromagnetic field. To the best of our knowledge, this is the first time that such type of nanoformulation with very promising hyperthermia characteristics has been developed for therapeutic aims.


Asunto(s)
Neoplasias del Colon/terapia , Hipertermia Inducida/métodos , Nanopartículas de Magnetita/administración & dosificación , Nanocompuestos/administración & dosificación , Adulto , Coagulación Sanguínea/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Femenino , Células HT29 , Hemólisis/efectos de los fármacos , Humanos , Nanopartículas de Magnetita/química , Nanocompuestos/química , Activación Plaquetaria/efectos de los fármacos , Triglicéridos/química , Adulto Joven
10.
Eur. j. anat ; 19(2): 131-137, abr. 2015. tab
Artículo en Inglés | IBECS | ID: ibc-141202

RESUMEN

Currently, biomedical research is mainly focused on overcoming the major challenges faced by society, including the development of new therapeutic strategies against highly prevalent diseases. Over the past 20 years, considerable advances in this field have been achieved through an interdisciplinary and collaborative approach, enhanced by the development of computer science and its applications in genomics and proteomics. This study centers on platforms for the data management of research assets with high specialization in genomics and proteomics, analyzing the role of web-based databases in the progress made in these areas and evaluating their impact on global scientific production. The web platforms analyzed have proven to be an important resource for stimulating the integration of research data through information exchange. Specialized web search sites facilitate the obtaining of data in these specific areas, creating a trend in current biomedical research. The importance of these platforms is revealed by their impact on scientific production, with some being referenced in more than 100,000 articles and patents. A wider extension of the use of these tools can be expected within the modern society of information


No disponible


Asunto(s)
Proteómica/tendencias , Genómica/tendencias , Investigación Biomédica/tendencias , Bases de Datos Bibliográficas , Acceso a la Información , Terminología como Asunto
11.
Pancreas ; 43(7): 1042-9, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24979617

RESUMEN

OBJECTIVE: Pancreatic ductal adenocarcinoma is a deadly disease because of late diagnosis and chemoresistance. We aimed to find a panel of serum cytokines representing diagnostic and predictive biomarkers for pancreatic cancer. METHODS: A cytokine antibody array was performed to simultaneously identify 507 cytokines in sera of patients with pancreatic cancer and healthy controls. The nonparametric Mann-Whitney U test was used to pairwise compare the controls, the pretreated patients, and the posttreated patients. Fold changes greater than or equal to 1.5 or less than or equal to 1/1.5 were considered significant. Receiver operating characteristic curves were used to assess the performance of the model. A leave-one-out cross-validation was used for estimating prediction error. RESULTS: Comparing the sera of pretreated patients against the control samples, the cytokines fibroblast growth factor 10 (FGF-10/keratinocyte growth factor-2 (KGF-2), chemokine (C-X-C motif) ligand 11 interferon inducible T cell alpha chemokine (I-TAC)/chemokine [C-X-C motif] ligand 11 (CXCL11), oncostatin M (OSM), osteoactivin/glycoprotein nonmetastatic melanoma protein B, and stem cell factor (SCF) were found significantly overexpressed. Besides, the cytokines CD30 ligand/tumor necrosis factor superfamily, member 8 (TNFSF8), chordin-like 2, FGF-10/KGF-2, growth/differentiation factor 15, I-TAC/CXCL11, OSM, and SCF were differentially expressed in response to treatment. CONCLUSIONS: We propose a role for FGF-10/KGF-2, I-TAC/CXCL11, OSM, osteoactivin/glycoprotein nonmetastatic melanoma protein B, and SCF as novel diagnostic biomarkers. CD30 ligand/TNFSF8, chordin-like 2, FGF-10/KGF-2, growth/differentiation factor 15, I-TAC/CXCL11, OSM, and SCF might represent as predictive biomarkers for gemcitabine and erlotinib response of patients with pancreatic cancer.


Asunto(s)
Biomarcadores de Tumor/sangre , Carcinoma Ductal Pancreático/sangre , Citocinas/sangre , Proteínas de Neoplasias/sangre , Neoplasias Pancreáticas/sangre , Anciano , Antígenos de Neoplasias/sangre , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Área Bajo la Curva , Antígeno CA-19-9/sangre , Antígeno Carcinoembrionario/sangre , Carcinoma Ductal Pancreático/tratamiento farmacológico , Carcinoma Ductal Pancreático/epidemiología , Comorbilidad , Desoxicitidina/administración & dosificación , Desoxicitidina/análogos & derivados , Diabetes Mellitus Tipo 2/epidemiología , Clorhidrato de Erlotinib , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/epidemiología , Valor Predictivo de las Pruebas , Quinazolinas/administración & dosificación , Curva ROC , Sensibilidad y Especificidad , Fumar/epidemiología , Microambiente Tumoral , Gemcitabina
12.
Eur J Pharm Biopharm ; 85(3 Pt A): 329-38, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23485475

RESUMEN

The present investigation aimed to develop magnetoliposome nanoparticles loaded with 5-fluorouracil by following a reproducible thin film hydration technique. The physicochemical characterization (including electron microscopy analysis, dynamic light scattering, infrared spectrometry, X-ray diffractometry, electrophoresis, and surface thermodynamics) suggested that superparamagnetic magnetite nuclei were successfully embedded into a multilamellar lipid vesicle. Magnetic responsiveness of these nanocomposites was quantitatively analyzed by determining the hysteresis cycle and qualitatively confirmed by microscopic visualizations. A high frequency alternating electromagnetic field was further used to define their heating properties. The absence of cytotoxicity in human colon fibroblast CCD-18 and in human colon carcinoma T-84 cell lines and excellent hemocompatibility of these core/shell particles were demonstrated. Additionally, 5-fluorouracil incorporation was investigated by two procedures: (i) entrapment into the nanoparticulate matrix and (ii) surface deposition onto already formed magnetoliposome particles. The former method reported greater drug loading values and a sustained release profile. Interestingly, 5-fluorouracil release was also triggered by the heating properties of the nanoparticles (hyperthermia-triggered drug release). Hence, we put forward that magnetoliposome particles hold important properties, that is, magnetically targeted delivery, hyperthermia inducing capability, high 5-fluorouracil loading capability, and hyperthermia-triggered burst drug release, suggestive of their potential for a combined antitumor therapy against colon cancer.


Asunto(s)
Antimetabolitos Antineoplásicos/administración & dosificación , Neoplasias del Colon/tratamiento farmacológico , Fluorouracilo/administración & dosificación , Nanopartículas de Magnetita , Adulto , Antimetabolitos Antineoplásicos/química , Antimetabolitos Antineoplásicos/farmacología , Línea Celular Tumoral , Química Farmacéutica , Neoplasias del Colon/patología , Preparaciones de Acción Retardada , Composición de Medicamentos , Sistemas de Liberación de Medicamentos , Fenómenos Electromagnéticos , Femenino , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Fluorouracilo/química , Fluorouracilo/farmacología , Humanos , Hipertermia Inducida/métodos , Liposomas , Magnetismo , Persona de Mediana Edad
13.
Int J Pharm ; 443(1-2): 103-9, 2013 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-23299085

RESUMEN

We investigated the incorporation of gemcitabine into a colloidal carrier based on the biodegradable and biocompatible poly(d,l-lactide-co-glycolide) (PLGA) to optimize its anticancer activity. Two synthesis techniques (double emulsion/solvent evaporation, and Flow Focusing) were compared in terms of particle geometry, electrophoretic properties (surface charge), gemcitabine vehiculization capabilities (drug loading and release), blood compatibility, and in vitro antitumor activity. To the best of our knowledge, the second formulation methodology (Flow Focusing) has never been applied to the synthesis of gemcitabine-loaded PLGA particles. With the aim of achieving the finest (nano)formulation, experimental parameters associated to these preparation procedures were analyzed. The electrokinetics of the particles suggested that the chemotherapy agent was incorporated into the polymeric matrix. Blood compatibility was demonstrated in vitro. Flow Focusing led to a more appropriate geometry, higher gemcitabine loading and a sustained release profile. In addition, the cytotoxicity of gemcitabine-loaded particles prepared by Flow Focusing was tested in MCF-7 human breast adenocarcinoma cells, showing significantly greater antitumor activity compared to the free drug and to the gemcitabine-loaded particles synthesized by double emulsion/solvent evaporation. Thus, it has been identified the more adequate formulation conditions in the engineering of gemcitabine-loaded PLGA nanoparticles for the effective treatment of tumours.


Asunto(s)
Antimetabolitos Antineoplásicos/administración & dosificación , Materiales Biocompatibles/química , Desoxicitidina/análogos & derivados , Portadores de Fármacos/química , Nanopartículas/química , Tecnología Farmacéutica/métodos , Antimetabolitos Antineoplásicos/química , Supervivencia Celular/efectos de los fármacos , Coloides , Desoxicitidina/administración & dosificación , Desoxicitidina/química , Composición de Medicamentos , Femenino , Humanos , Ácido Láctico/química , Células MCF-7 , Tamaño de la Partícula , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Solubilidad , Gemcitabina
14.
J Anat ; 220(6): 580-90, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22428933

RESUMEN

The development of the human wrist joint has been studied widely, with the main focus on carpal chondrogenesis, ligaments and triangular fibrocartilage. However, there are some discrepancies concerning the origin and morphogenetic time-table of these structures, including nerves, muscles and vascular elements. For this study we used serial sections of 57 human embryonic (n = 30) and fetal (n = 27) specimens from O'Rahilly stages 17-23 and 9-14 weeks, respectively. The following phases in carpal morphogenesis have been established: undifferentiated mesenchyme (stage 17), condensated mesenchyme (stages 18 and 19), pre-chondrogenic (stages 19 and 20) and chondrogenic (stages 21 and over). Carpal chondrification and osteogenic processes are similar, starting with capitate and hamate (stage 19) and ending with pisiform (stage 22). In week 14, a vascular bud penetrates into the lunate cartilaginous mold, early sign of the osteogenic process that will be completed after birth. In stage 18, median, ulnar and radial nerves and thenar eminence appear in the hand plate. In stage 21, there are indications of the interosseous muscles, and in stage 22 flexor digitorum superficialis, flexor digitorum profundus and lumbrical muscles, transverse carpal ligament and collateral ligaments emerge. In stage 23, the articular disc, radiocarpal and ulnocarpal ligaments and deep palmar arterial arch become visible. Radiate carpal and interosseous ligaments appear in week 9, and in week 10, dorsal radiocarpal ligament and articular capsule are evident. Finally, synovial membrane is observed in week 13. We have performed a complete analysis of the morphogenesis of the structures of the human wrist joint. Our results present new data on nervous and arterial elements and provide the basis for further investigations on anatomical pathology, comparative morphology and evolutionary anthropology.


Asunto(s)
Articulación de la Muñeca/embriología , Huesos del Carpo/embriología , Cartílago Articular/embriología , Edad Gestacional , Humanos , Ligamentos Articulares/embriología , Morfogénesis
15.
Ital J Anat Embryol ; 111(1): 45-64, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16736717

RESUMEN

Differentiation is a complex multistep process of cell specialization that begins with the installation of a genetic programme, named determination, specific for a cell lineage. Development of the differentiation programme includes the cell-type specific silencing of some genes and the expression of other genes, that regulate the biological functions associated with the cellular type and that distinguish the specialized cells. Terminal differentiation is the end stage of this process where the cells irreversibly lose their proliferative capacity and which represents a form of negative control of growing. Regulating molecules interact to produce the correct balance between cellular multiplication and differentiation during embryogenesis and the normal behaviour of an adult. Cancer is a process in which changes in regulating circuits are produced, such as proliferation control, the balance between cellular survival and programmed cellular death (apoptosis), the communication with neighbouring cells and with the extracellular matrix, angiogenesis, and finally, the migration of the tumoural cell, the invasion and metastasic dissemination. This process implies the progressive development of a more malign phenotype with an increase of genetic alterations involving genes at several levels of expression during long periods of time. These genetic changes uncouple the normal balance between multiplication and cellular differentiation with an increase in the rate of proliferating cells. Classic chemotherapeutical agents have been very important; nevertheless, as the mechanism of action of these drugs depends on the cytodestruction of the neoplastic cells, their beneficial effects are normally accompanied by a notable morbidity, cytotoxicity and multidrug resistance. The knowledge of the mechanisms involved in differentiation and malignant transformation has allowed the search of alternative routes for antitumoural therapy that does not imply cellular death. Differentiation therapy focuses on the development and use of specific agents designed to selectively attract the terminal differentiation process, making the elimination of tumoural cells feasible together with the establishment of normal cellular homeostasis.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Diferenciación Celular/efectos de los fármacos , Transformación Celular Neoplásica/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Neoplasias/fisiopatología , Neoplasias/terapia , Animales , Muerte Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Transformación Celular Neoplásica/metabolismo , Transformación Celular Neoplásica/patología , Homeostasis/efectos de los fármacos , Humanos
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