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1.
Carbohydr Polym ; 314: 120900, 2023 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-37173041

RESUMEN

An innovative hyaluronan-based nano-delivery system is proposed for the active targeting towards ER+ breast cancer. Hyaluronic acid (HA), an endogenous and bioactive anionic polysaccharide, is functionalized with estradiol (ES), a sexual hormone involved in the development of some hormone-dependent tumors, to give an amphiphilic derivative (HA-ES) able to spontaneously self-assemble in water to form soft nanoparticles or nanogels (NHs). The synthetic strategy used to obtain the polymer derivatives and the physico-chemical properties of the obtained nanogels (ES-NHs) are reported. ES-NHs ability to entrap hydrophobic molecules has also been investigated, by loading curcumin (CUR) and docetaxel (DTX), both able to inhibit the growth of ER+ breast cancer. The formulations are studied for their capability to inhibit the growth of the MCF-7 cell line, thus evaluating their efficacy and potential as a selective drug delivery systems. Our results demonstrate that ES-NHs have not toxic effects on the cell line, and that both ES-NHs/CUR and ES-NHs/DTX treatments inhibit MCF-7 cell growth, with ES-NHs/DTX effect higher than that of free DTX. Our findings support the use of ES-NHs to deliver drugs to ER+ breast cancer cells, assuming a receptor-dependent targeting.


Asunto(s)
Antineoplásicos , Neoplasias de la Mama , Curcumina , Nanopartículas , Humanos , Femenino , Portadores de Fármacos/química , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Ácido Hialurónico/química , Nanogeles/uso terapéutico , Estradiol/farmacología , Docetaxel/uso terapéutico , Sistemas de Liberación de Medicamentos , Curcumina/química , Células MCF-7 , Nanopartículas/química , Línea Celular Tumoral , Antineoplásicos/química
2.
Oncoimmunology ; 6(11): e1356151, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29147611

RESUMEN

Autophagy is usually a pro-survival mechanism in cancer cells, especially in the course of chemotherapy, thus autophagy inhibition may enhance the chemotherapy-mediated anti-cancer effect. However, since autophagy is strongly involved in the immunogenicity of cell death by promoting ATP release, its inhibition may reduce the immune response against tumors, negatively influencing the overall outcome of chemotherapy. In this study, we evaluated the in vitro and in vivo anti-cancer effect of curcumin (CUR) against Her2/neu overexpressing breast cancer cells (TUBO) in the presence or in the absence of the autophagy inhibitor chloroquine (CQ). We found that TUBO cell death induced by CUR was increased in vitro by CQ and slightly in vivo in nude mice. Conversely, CQ counteracted the Cur cytotoxic effect in immune competent mice, as demonstrated by the lack of in vivo tumor regression and the reduction of overall mice survival as compared with CUR-treated mice. Immunohistochemistry analysis revealed the presence of a remarkable FoxP3 T cell infiltrate within the tumors in CUR/CQ treated mice and a reduction of T cytotoxic cells, as compared with single CUR treatment. These findings suggest that autophagy is important to elicit anti-tumor immune response and that autophagy inhibition by CQ reduces such response also by recruiting T regulatory (Treg) cells in the tumor microenvironment that may be pro-tumorigenic and might counteract CUR-mediated anti-cancer effects.

3.
Plant Biol (Stuttg) ; 18(6): 1016-1024, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27487981

RESUMEN

Glycine max L. (soybean) is one of the major crops of the world. Although the process of biomineralisation has been reported in some organs of soybean, we now report the description and quantification of calcium oxalate crystals in vegetative and reproductive organs of soybean during its life cycle, as they act as an important source of calcium to the soil, once the harvesting is finished. Through diaphanisation, cross-sectioning, optical and scanning electron microscopy analysis of the organs, morphology, size and location of the crystals were identified. In addition, crystal density (n° crystals·mm-2 ) and the input of crystals to soil (n° crystals·ha-1 ) were calculated. Soybean produced prismatic calcium oxalate crystals in vegetative and reproductive organs, generally associated with vascular bundles, resulting in a potencial transfer to the soil of 81.4 x 107 crystals·ha-1 throughout its life cycle. Pods were the organs with higher calcium oxalate crystal production (1112.7 ± 384.6 crystals·mm-2 ), but with the smaller size (12.3 ± 2.1 µm long). However, cotyledons were the organs that produce the larger crystals (21.3 ± 3.5 µm long), but in lesser amounts (150.9 ± 64.4 crystals·mm-2 ). In leaves, although crystal size did not differ from vegetative to reproductive stage (14.5 ± 4.2 and 14.5 ± 4 µm in length, respectively), the crystal density increased (293.2 and 409 crystals·mm-2 , respectively). These results will contribute to knowledge of the amount of calcium oxalate crystals involved in the process of Ca recycling through cultivated vegetation in fields from humid plains at medium latitudes, which therefore have biological, botanical, biogeochemical and pedological relevance.


Asunto(s)
Oxalato de Calcio/metabolismo , Calcio/metabolismo , Glycine max/metabolismo , Microscopía Electrónica de Rastreo , Hojas de la Planta/química , Hojas de la Planta/metabolismo , Hojas de la Planta/ultraestructura , Suelo/química , Glycine max/química , Glycine max/ultraestructura
4.
Plant Biol (Stuttg) ; 18(6): 1025-1030, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27488096

RESUMEN

Grasses accumulate high amounts of silica deposits in tissues of all their organs, especially at mature stage. However, when and under which conditions do grass seedlings begin to produce these silica deposits and their relation with anatomy and development is little known. Here we investigated the silicification process in the first leaves and roots of seedlings of Bothriochloa laguroides grown in different substrate and Si treatments. The distribution and content of silica deposits in the organs of the seedlings grown under different conditions were analyzed through staining techniques and SEM-EDAX analyses. Leaf silica deposits were accumulated 3-4 days after the first leaf emergence, also under low silica solution (0.17-0.2 mM). Their location was mainly restricted to short costal cells from basal sectors, and scarcely in trichomes and xylem at tips. Silica content in leaves increased with the age of the seedlings. Roots presented dome-shaped silica aggregates, between 4-12 µm of diameter, located in the inner tangential wall of endodermal cells and similar to those produced at maturity. Silicification begins early in the first photosynthetic leaf, and silica distribution is opposite to that found in mature plants, mainly restricted to basal sectors, probably acting as a reinforcing element. The fast incorporation of solid amorphous silica in leaves and roots, may be useful for farm applications in species that are Si-fertilized.


Asunto(s)
Poaceae/metabolismo , Dióxido de Silicio/metabolismo , Especificidad de Órganos , Hojas de la Planta/química , Hojas de la Planta/metabolismo , Hojas de la Planta/ultraestructura , Raíces de Plantas/química , Raíces de Plantas/metabolismo , Raíces de Plantas/ultraestructura , Poaceae/química , Poaceae/ultraestructura , Plantones/química , Plantones/metabolismo , Plantones/ultraestructura
5.
J Biol Regul Homeost Agents ; 27(1): 105-19, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23489691

RESUMEN

Breast cancer is a leading cancer in women and despite the benefits of the current therapies a significant number of patients with this tumor is at risk of relapse. Some of the alterations taking place in breast cancer cells are currently exploited by molecularly targeted drugs. Different drugs have been developed which target a single molecule but, given that the tumor originates from the dysregulation of many genes, there is the need to find new drugs that have more than one molecular target. Curcumin [1,7-bis-(4-hydroxy-3-methoxyphenyl)-1,6-heptadiene-3,5-dione] (CUR), a polyphenolic compound found in the spice turmeric, is a pleiotropic molecule able to interact with a variety of molecular targets and has antitumor, anti-inflammatory, antioxidant, immunomodulatory and antimicrobial activities. Here we demonstrate that CUR inhibits the growth of breast cancer cell lines in a dose dependent manner, with IC50 values in the micromolar range, and induces an increase in the percentage of cells in sub-G0 phase, representing the apoptotic cell population. The activation of apoptosis was confirmed by PARP-1 cleavage and by the increased ratio between the pro-apoptotic Bax and the anti-apoptotic Bcl-2 protein. In addition, in CUR-treated cells the activity of ERK1/ERK2 MAP kinases was down-regulated. The cytotoxic effects of CUR were observed in breast cancer cells expressing either high or low levels of ErbB2/neu. The in vivo antitumor activity of CUR was tested in BALB-neuT mice transgenic for the neu oncogene, which develop atypical hyperplasia of the mammary gland at 6 weeks of age and invasive carcinoma at 16 weeks of age. CUR, administered to mice both early and in an advanced stage of mammary carcinogenesis, induced a significant prolongation of tumor-free survival and a reduction of tumor multiplicity. In addition, CUR administration was safe, since no modification of hematological and clinical chemistry parameters could be observed in BALB-neuT and BALB/c mice treated with this compound for several weeks. These findings support further studies on the therapeutic potential of CUR in combination with standard therapies in breast cancer patients.


Asunto(s)
Apoptosis/efectos de los fármacos , Neoplasias de la Mama/patología , Curcumina/farmacología , Neoplasias Mamarias Animales/patología , Receptor ErbB-2/metabolismo , Animales , Neoplasias de la Mama/tratamiento farmacológico , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Curcumina/efectos adversos , Curcumina/uso terapéutico , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Fibroblastos/patología , Humanos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Neoplasias Mamarias Animales/sangre , Neoplasias Mamarias Animales/tratamiento farmacológico , Ratones , Ratones Endogámicos BALB C , Ratones Transgénicos , Células 3T3 NIH , Fosforilación/efectos de los fármacos , Poli(ADP-Ribosa) Polimerasas/metabolismo , Ratas , Receptor ErbB-2/genética , Proteína X Asociada a bcl-2/metabolismo
6.
Osteoporos Int ; 21(8): 1323-30, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19809775

RESUMEN

SUMMARY: A total of 507,671 people > or =65 experienced hip fractures between 2000 and 2005. In 2005, 94,471 people > or =65 were hospitalized due to hip fractures, corresponding to a 28.5% increase over 6 years. Most fractures occurred in patients > or =75 (82.9%; n = 420,890; +16% across 6 years), particularly in women (78.2%; n = 396,967). INTRODUCTION: We aimed to analyze incidence and costs of hip fractures in Italy over the last 6 years. METHODS: We analyzed the national hospitalization and DRG databases concerning fractures occurred in people > or =65 between 2000 and 2005. RESULTS: A total of 507,671 people > or =65 experienced hip fractures across 6 years, resulting in about 120,000 deaths. In year 2005 94,471 people aged > or =65 were hospitalized due to hip fractures, corresponding to a 28.5% increase over 6 years. The majority of hip fractures occurred in patients > or =75 (82.9%; n = 420,890; +16% across 6 years) and particularly in women (78.2%; n = 396,967). Among women, 84.2% of fractures (n = 334,223; +28.0% over 6 years) were experienced by patients > or =75, which is known to be the age group with the highest prevalence of osteoporosis, accounting for 68.6% of the overall observed increase in the total number of fractures. Hip fractures in men > or =75 increased by 33.1% (up to 16,540). Hospitalization costs increased across the six examined years (+36.1%) reaching 467 million euros in 2005, while rehabilitation costs rose up to 531 million in the same year. CONCLUSIONS: Hip fractures of the elderly are increasing and represent a major health problem in industrialized countries such as Italy.


Asunto(s)
Fracturas de Cadera/epidemiología , Fracturas Osteoporóticas/epidemiología , Distribución por Edad , Anciano , Grupos Diagnósticos Relacionados , Femenino , Costos de la Atención en Salud/estadística & datos numéricos , Fracturas de Cadera/rehabilitación , Hospitalización/estadística & datos numéricos , Hospitalización/tendencias , Humanos , Incidencia , Italia/epidemiología , Masculino , Persona de Mediana Edad , Fracturas Osteoporóticas/rehabilitación , Distribución por Sexo
7.
Cir Esp ; 80(1): 3-8, 2006 Jul.
Artículo en Español | MEDLINE | ID: mdl-16796946

RESUMEN

Insulinoma is the most frequent neuroendocrine pancreatic tumor. In the present study, the clinical and immunohistochemical results of 20 patients who underwent surgery between January 1986 and December 2004 were evaluated. Clinical presentation, laboratory data, imaging studies, aspects of the surgical technique, complication rates and medium- and long-term follow-up were analyzed. Surgical treatment was recommended in all patients based on presenting symptoms and laboratory signs of hypoglycemia and hyperinsulinemia. In 15 patients, the lesion was identified preoperatively. In the 5 remaining patients, intraoperative palpation and ultrasonography were used to locate the lesion. The most frequently performed surgical procedures were pancreatic resection in 10 patients and laparotomic enucleation in the remaining 10. Laparoscopy was used in two patients. Two patients developed diabetes mellitus. The most frequent surgical complication was pancreatic fistula. No mortality was observed in the present series. Symptom reversion, characterized by disappearance of Whipple's triad and normal or increased glycemia values compared with preoperative values, was observed in all patients.


Asunto(s)
Insulinoma , Neoplasias Pancreáticas , Adolescente , Adulto , Anciano , Femenino , Humanos , Insulinoma/patología , Insulinoma/cirugía , Masculino , Persona de Mediana Edad , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/cirugía
9.
Tissue Eng ; 6(1): 39-44, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10941199

RESUMEN

Our laboratory has investigated hepatocyte transplantation using biodegradable polymer matrices as an alternative treatment to end-stage liver disease. One of the major limitations has been the insufficient survival of an adequate mass of transplanted cells. This study investigates a novel method of dynamic seeding and culture of hepatocytes in a flow perfusion system. In experiment I, hepatocytes were flow-seeded onto PGA scaffolds and cultured in a flow perfusion system for 24 h. Overall metabolic activity and distribution of cells were assessed by their ability to reduce MTT. DNA quantification was used to determine the number of cells attached. Culture medium was analyzed for albumin content. In Experiment II, hepatocyte/polymer constructs were cultured in a perfusion system for 2 and 7 days. The constructs were examined by SEM and histology. Culture medium was analyzed for albumin. In experiment I, an average of 4.4 X 10(6) cells attached to the scaffolds by DNA quantification. Cells maintained a high metabolic activity and secreted albumin at a rate of 13 pg/cell/day. In experiment II, SEM demonstrated successful attachment of hepatocytes on the scaffolds after 2 and 7 days. Cells appeared healthy on histology and maintained a high rate of albumin secretion through day 7. Hepatocytes can be dynamically seeded onto biodegradable polymers and survive with a high rate of albumin synthesis in the flow perfusion culture system.


Asunto(s)
Técnicas de Cultivo de Célula/métodos , Hígado/citología , Albúminas/metabolismo , Animales , Materiales Biocompatibles , Ingeniería Biomédica , Supervivencia Celular , Trasplante de Células , Hígado/fisiología , Trasplante de Hígado , Microscopía Electrónica de Rastreo , Perfusión , Ácido Poliglicólico , Ratas
10.
Tissue Eng ; 5(6): 525-32, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10611544

RESUMEN

Skeletal muscle is responsible for the control of voluntary movement and the maintenance of structural contours of the body. Muscle loss or deficiency is encountered in various pathological states, and attempts to correct them have been employed with limited success. The aim of the present study was to tissue engineer three-dimensional vascularized skeletal muscle using isolated myoblasts attached to synthetic biodegradable polymer for tissue replacement in the enhancement of muscle regeneration. Myoblasts derived from neonatal rats (3-5-day-old), Fisher CDF-F344, were seeded onto polyglycolic acid meshes and implanted into the omentum of syngeneic adult Fisher CDF-F344 rats. Rats were sacrificed on day 30 and day 45 after the transplantation, and the cell-polymer constructs were harvested for morphological analysis. Histological analysis of the constructs were performed by hematoxylin and eosin, and immunohistochemical staining was positive for alpha sarcomeric actin and desmin skeletal muscle marker. Viable myoblasts organized between strands of degrading polymer mesh formed the new tissue, and vascularization of the entire construct was observed. Organization of neomuscle strands surrounded by vascularized tissue composed of degrading polymer and fusing myoblasts demonstrated the ability of myoblast constructs to survive, reorganize and regenerate tissue-like structures. Since myoblast transplantation to date has been limited to the cellular level of replacement, myoblast-polyglycolic acid constructs may be useful in defining the application of tissue engineering for future skeletal muscle transplantations.


Asunto(s)
Materiales Biocompatibles , Trasplante de Células/instrumentación , Implantes Experimentales , Músculo Esquelético/citología , Ácido Poliglicólico , Polímeros , Mallas Quirúrgicas , Actinas/análisis , Animales , Biodegradación Ambiental , Biomarcadores , Desmina/análisis , Femenino , Supervivencia de Injerto , Masculino , Epiplón , Ratas , Ratas Endogámicas F344 , Trasplante Heterotópico
11.
J Surg Res ; 87(1): 6-13, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10527698

RESUMEN

BACKGROUND: Our laboratory is investigating the tissue engineering of small intestine using intestinal epithelial organoid units seeded onto highly porous biodegradable polymer matrices. This study investigated the effects of anastomosis of tissue-engineered intestine to native small bowel alone or combined with small bowel resection on neointestinal regeneration. METHODS: Intestinal epithelial organoid units harvested from neonatal Lewis rats were seeded onto biodegradable polymer tubes and implanted into the omentum of adult Lewis rats as follows: (1) implantation alone (n = 9); (2) implantation followed by anastomosis to native small bowel at 3 weeks (n = 11); and (3) implantation after small bowel resection and anastomosis to native small bowel at 3 weeks (n = 8). All constructs were harvested at 10 weeks and examined by histology. Morphometric analysis of the neomucosa was obtained using a computer image analysis program. RESULTS: Cyst development was noted in all animals. All anastomoses were patent at 10 weeks. Histology revealed the development of a vascularized tissue with a neomucosa lining the lumen of the cyst with invaginations resembling crypt-villus structures. Morphometric analysis demonstrated significantly greater villus number, villus height, crypt number, crypt area, and mucosal surface length in groups 2 and 3 compared with group 1, and significantly greater villus number, villus height, crypt area, and mucosal surface length in group 3 compared with group 2 (P < 0.05, ANOVA, Tukey test). CONCLUSION: Intestinal epithelial organoid units transplanted on biodegradable polymer tubes can regenerate into complex tissue resembling small intestine. Anastomosis to native small bowel combined with small bowel resection and anastomosis alone contribute significant regenerative stimuli for the morphogenesis and differentiation of tissue-engineered neointestine.


Asunto(s)
Anastomosis Quirúrgica , Trasplante de Células , Intestino Delgado/citología , Intestino Delgado/cirugía , Animales , Mucosa Intestinal/patología , Ratas , Ratas Endogámicas Lew
12.
Tissue Eng ; 5(4): 339-46, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10477856

RESUMEN

The purpose of this study was to demonstrate the feasibility of end-to-end anastomosis between tissue-engineered intestine and native small bowel and to investigate the effect of this anastomosis on their growth. Microporous biodegradable polymer tubes were created from a fiber mesh of polyglycolic acid sprayed with 5% polylactic acid. Intestinal epithelial organoid units were harvested from neonatal Lewis rats and seeded onto polymers. These constructs were implanted into the omentum of adult Lewis rats. Three weeks after the implantation, the constructs (n = 7) were anastomosed to the native jejunum in an end-to-end fashion. Ten weeks after implantation, the tissue-engineered intestine was harvested. Four of 7 rats survived for 10 weeks and the overall patency rate of the anastomosis was 78% (11 of 14 anastomosis). The maximal length of the tissue-engineered intestine at week 3 and 10 was 1.80 +/- 0.32 and 1.93 +/- 0.39 cm (mean +/- SD). Histologically, the tissue-engineered intestine was lined with a well-developed neomucosal layer that was continuous with the native intestine. We conclude that anastomosis between tissue-engineered intestine and native small bowel had a moderately high patency rate and had a positive effect on maintenance of the size of the neointestine and development of the neomucosa.


Asunto(s)
Anastomosis Quirúrgica/métodos , Órganos Artificiales , Mucosa Intestinal/citología , Mucosa Intestinal/cirugía , Intestino Delgado/cirugía , Animales , Animales Recién Nacidos , Materiales Biocompatibles , Ingeniería Biomédica , Trasplante de Células , Femenino , Mucosa Intestinal/fisiología , Ácido Láctico , Masculino , Epiplón , Poliésteres , Ácido Poliglicólico , Polímeros , Ratas , Ratas Endogámicas Lew
15.
J Pediatr Surg ; 34(1): 124-8, 1999 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10022156

RESUMEN

BACKGROUND/PURPOSE: Hepatotrophic factors in the portal blood are critically important for the survival of heterotopically transplanted hepatocytes. Currently, no model exists for the implantation of hepatocytes on biodegradable polymer scaffolds with direct access to the portal blood. This study investigates the use of small intestinal submucosa (SIS) as a small-caliber venous conduit that may be used for the implantation of tissue-engineered liver. METHODS: SIS was prepared from segments of rat jejunum and implanted as a venous conduit between the portal vein and inferior vena cava in 26 heparinized Lewis rats. Venograms were performed periodically, and the grafts were harvested at various time-points and examined by scanning electron microscopy (SEM) and histology. Von Willebrand Factor (vWF) staining was performed to assess endothelialization. RESULTS: Five rats died of technical complications. Seventeen of 21 rats (81%) maintained patent grafts at the time of death up to 8 weeks. Venograms demonstrated patent grafts at 3 and 8 weeks. SEM results showed a smooth luminal surface with endothelial-like cells by 3 weeks. Histology demonstrated a confluent luminal endothelial monolayer, absence of thrombus, and neovascularization in the SIS graft. VWF staining results were positive, confirming the growth of endothelial cells on the luminal surface. In preliminary studies, implantation of hepatocytes seeded on biodegradable polymer tubes into the SIS graft demonstrated clusters of viable cells after 2 days. CONCLUSIONS: Rat SIS can be prepared readily, maintains high patency as a small-caliber venous graft, and may be a useful model for the transplantation of tissue-engineered liver with access to the portal circulation.


Asunto(s)
Prótesis Vascular , Trasplante de Células , Mucosa Intestinal , Circulación Hepática , Hígado/citología , Sistema Porta , Animales , Técnicas de Cultivo de Célula , Yeyuno , Hígado Artificial , Masculino , Ratas , Ratas Endogámicas Lew
16.
Transplantation ; 67(2): 227-33, 1999 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-10075585

RESUMEN

BACKGROUND: Our laboratory is investigating the tissue engineering of small intestine using intestinal epithelial organoid units seeded onto highly porous biodegradable polymer tubes. This study investigated methods of stimulation for optimizing neointestinal regeneration. METHODS: Intestinal epithelial organoid units harvested from neonatal Lewis rats were seeded onto porous biodegradable polymer tubes and implanted into the omentum of adult Lewis rats in the following groups: (1) the control group (group C), implantation alone (n=9); (2) the small bowel resection (SBr) group, after 75% SBr (n=9); (3) the portacaval shunt (PCS) group, after PCS (n=8); and (4) the partial hepatectomy (PH) group, after 75% PH (n=8). Neointestinal cyst size was recorded using ultrasonography. Constructs were harvested at 10 weeks and were examined using histology. Morphometric analysis of the neomucosa was obtained using a computer image analysis program (NIH Image, version 1.59). RESULTS: Cyst development was noted in all animals. Cyst lengths and diameters were significantly larger in the SBr group at 7 and 10 weeks compared with the other three groups (P<0.05; analysis of variance [ANOVA], Fisher's protected least significant difference). Histology revealed a well-vascularized tissue with a neomucosa lining the lumen with invaginations resembling crypt-villus structures. Morphometric analysis demonstrated a significantly greater villus number, height, area, and mucosal surface in the SBr group compared with the other three groups and a significantly greater crypt number and area in the PCS group compared with group C (P<0.05; ANOVA, Fisher's protected least significant difference). CONCLUSIONS: Intestinal epithelial organoid units transplanted on porous biodegradable polymer tubes can successfully vascularize, survive, and regenerate into complex tissue resembling small intestine. SBr and, to a lesser extent, PCS provide significant regenerative stimuli for the morphogenesis and differentiation of tissue-engineered small intestine.


Asunto(s)
Materiales Biocompatibles , Mucosa Intestinal/fisiología , Mucosa Intestinal/trasplante , Intestino Delgado/fisiología , Intestino Delgado/trasplante , Organoides/fisiología , Trasplante Isogénico/fisiología , Animales , Animales Recién Nacidos , Peso Corporal , Quistes/diagnóstico por imagen , Quistes/patología , Hepatectomía , Procesamiento de Imagen Asistido por Computador , Mucosa Intestinal/citología , Masculino , Neovascularización Fisiológica , Organoides/ultraestructura , Ácido Poliglicólico , Derivación Portocava Quirúrgica , Ratas , Ratas Endogámicas Lew , Regeneración , Transducción de Señal , Trasplante Isogénico/métodos , Ultrasonografía
17.
Transplantation ; 67(2): 241-5, 1999 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-10075587

RESUMEN

BACKGROUND: Previous work from this laboratory has shown that isolated intestinal epithelial organoid units on porous biodegradable polymer scaffolds formed vascularized cysts lined by a neomucosa. The purpose of this study was to demonstrate anastomosis between tissue-engineered intestine and the native small bowel and to observe the effect of this anastomosis on cyst growth. METHODS: Intestinal epithelial organoid units from neonatal Lewis rats were seeded onto porous biodegradable polymer tubes made of polyglycolic acid, and they were implanted into the omentum of adult male Lewis rats. Three weeks after implantation, the unit-polymer constructs were anastomosed in a side-to-side fashion to the native jejunum in 20 rats (group 1). The other 18 rats were closed without anastomosis (group 2). All 38 tissue-engineered constructs were harvested 10 weeks after implantation. Four rats underwent upper gastrointestinal (GI) study before they were killed. RESULTS: The rats in group 1 increased their body weights equal to those in group 2, and there was no statistically significant difference between the two groups. Upper GI examinations revealed no evidence of either bowel stenosis or obstruction at the anastomotic site. Grossly, the patency of the anastomosis was 90% and the lumen of the cyst was visualized by the upper GI study. At the second operation, there was no significant difference in the size of the cysts in either group: however, at the time the rats were killed, the length of the cysts in group 1 was significantly longer than that in group 2 (P<0.05 using Mann-Whitney U test). Histological examination showed that cysts after anastomosis were lined by a neomucosa in continuity to native small bowel across the anastomotic site and also demonstrated crypt-villus structures. Morphometric study demonstrated that cysts in group 1 had significantly greater villus number, height, and surface length than did those in group 2. CONCLUSIONS: Anastomosis between tissue-engineered intestine and native small bowel resulted in no complications after the operation, kept a high patency rate, and maintained mucosal continuity between the tissue-engineered intestine and native small bowel. Furthermore, anastomosis had a positive effect on cyst size and development of the mucosa in the tissue-engineered intestine.


Asunto(s)
Anastomosis Quirúrgica/métodos , Biopolímeros , Mucosa Intestinal/cirugía , Mucosa Intestinal/trasplante , Intestino Delgado/cirugía , Intestino Delgado/trasplante , Trasplante Isogénico/métodos , Animales , Animales Recién Nacidos , Quistes , Femenino , Mucosa Intestinal/fisiología , Intestino Delgado/fisiología , Masculino , Organoides/ultraestructura , Ácido Poliglicólico , Ratas , Ratas Endogámicas Lew , Trasplante Isogénico/patología , Trasplante Isogénico/fisiología
18.
Recenti Prog Med ; 84(11): 765-7, 1993 Nov.
Artículo en Italiano | MEDLINE | ID: mdl-8290788

RESUMEN

We describe a case of cardiac sarcoidosis manifested by arrhythmias, shock, chest pain, mitral valve prolapse and incompetence, aortic vascular involvement. Steroid therapy corrected shock and arrhythmias, but was unable to prevent the progression of the mitral valve insufficiency. Subsequently pulmonary and tricuspid valve incompetence were also observed.


Asunto(s)
Aorta , Cardiomiopatías/diagnóstico , Prolapso de la Válvula Mitral/etiología , Sarcoidosis/diagnóstico , Adulto , Humanos , Masculino , Sarcoidosis/complicaciones
20.
Rev Rhum Mal Osteoartic ; 58(7): 491-6, 1991.
Artículo en Francés | MEDLINE | ID: mdl-1925393

RESUMEN

The authors compare the results of valgisation tibial osteotomies in osteoarthrosis of the knee (146 cases) and osteoarthrosis of the knee with chondrocalcinosis (94 cases). The two groups were identical in terms of age, but differed by sex ratio (female predominance in CCA) and the initial radiological stage (more advanced forms in the CCA group). Results differed after the second year and reached significantly different values at 5 years (73% in knee osteoarthrosis as against 34% good clinical results in chondrocalcinosis). Study of two groups of patients paired for age, sex, weight and radiological stage showed that results at 5 years were significantly less good in the CCA group. These results are discussed and compared with those in the 1990 literature.


Asunto(s)
Condrocalcinosis/cirugía , Rodilla , Osteoartritis/cirugía , Osteotomía/métodos , Tibia/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Peso Corporal , Condrocalcinosis/complicaciones , Condrocalcinosis/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Osteoartritis/complicaciones , Osteoartritis/diagnóstico por imagen , Pronóstico , Radiografía , Estudios Retrospectivos , Factores de Tiempo
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