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1.
Carbohydr Polym ; 314: 120900, 2023 Aug 15.
Article in English | MEDLINE | ID: mdl-37173041

ABSTRACT

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.


Subject(s)
Antineoplastic Agents , Breast Neoplasms , Curcumin , Nanoparticles , Humans , Female , Drug Carriers/chemistry , Breast Neoplasms/drug therapy , Breast Neoplasms/pathology , Hyaluronic Acid/chemistry , Nanogels/therapeutic use , Estradiol/pharmacology , Docetaxel/therapeutic use , Drug Delivery Systems , Curcumin/chemistry , MCF-7 Cells , Nanoparticles/chemistry , Cell Line, Tumor , Antineoplastic Agents/chemistry
2.
Rev. esp. cardiol. (Ed. impr.) ; 75(11): 886-896, nov. 2022.
Article in Spanish | IBECS | ID: ibc-211710

ABSTRACT

Introducción y objetivos Los octogenarios representan el segmento de población de más rápida expansión en Europa; la prevalencia de la insuficiencia cardiaca (IC) en este grupo supera el 10%. Se evaluaron los cambios en las características clínicas, el tratamiento y los resultados a un año durante dos décadas en pacientes ambulatorios con IC crónica de edad ≥ 80 años incluidos en un registro nacional de cardiología. Métodos Se incluyó a 2 520 octogenarios con mediciones de la fracción de eyección ecocardiográfica basal y seguimiento a 1 año disponibles, inscritos en 138 clínicas ambulatorias de IC (21% de los hospitales nacionales con unidades de cardiología), reclutados a lo largo de tres épocas (1999-2005, 2006-2011, 2012-2018). Resultados En el momento de la inclusión, a lo largo de los 3 periodos de estudio, aumentaron la edad, el índice de masa corporal, la fracción de eyección, la prevalencia de obesidad, diabetes, dislipemia, hipertensión preexistente y la historia de fibrilación auricular. La proporción de pacientes con fracción de eyección conservada aumentó del 19,4% al 32,7% (p de tendencia <0,0001). Los marcadores de enfermedad avanzada se hicieron menos prevalentes. La prescripción de bloqueadores beta y antagonistas de los receptores de mineralocorticoides aumentó con el tiempo. Durante el seguimiento a un año, 308 pacientes fallecieron (12,2%) y 360 (14,3%) fueron ingresados por causas cardiovasculares; en total, 591 (23,5%) alcanzaron el objetivo primario combinado de mortalidad por todas las causas u hospitalización cardiovascular. Mediante un análisis multivariable ajustado, la inclusión en 2006-2011 (HR=0,70; IC95%, 0,55-0,90; p=0,004) y 2012-2018 (HR=0,61; IC95%, 0,47-0,79; p=0,0002), conllevó un menor riesgo del resultado primario que la inclusión en el periodo 1999-2005. Conclusiones Entre los octogenarios, a lo largo de 2 décadas, la prevalencia de los factores de riesgo aumentó (AU)


Introduction and objectives Octogenarians represent the most rapidly expanding population segment in Europe. The prevalence of heart failure (HF) in this group exceeds 10%. We assessed changes in clinical characteristics, therapy, and 1-year outcomes over 2 decades in chronic HF outpatients aged ≥ 80 years enrolled in a nationwide cardiology registry. Methods We included 2520 octogenarians with baseline echocardiographic ejection fraction measurements and available 1-year follow-up, who were recruited at 138 HF outpatient clinics (21% of national hospitals with cardiology units), across 3 enrolment periods (1999-2005, 2006-2011, 2012-2018).Result At recruitment, over the 3 study periods, there was an increase in age, body mass index, ejection fraction, the prevalence of obesity, diabetes, dyslipidemia, pre-existing hypertension, and atrial fibrillation history. The proportion of patients with preserved ejection fraction rose from 19.4% to 32.7% (P for trend <.0001). Markers of advanced disease became less prevalent. Prescription of beta-blockers and mineralocorticoid receptor antagonists increased over time. During the 1-year follow-up, 308 patients died (12.2%) and 360 (14.3%) were admitted for cardiovascular causes; overall, 591 (23.5%) met the combined primary endpoint of all-cause mortality or cardiovascular hospitalization. On adjusted multivariable analysis, enrolment in 2006 to 2011 (HR, 0.70; 95%CI, 0.55-0.90; P=.004) and 2012 to 2018 (HR, 0.61; 95%CI, 0.47-0.79; P=.0002) carried a lower risk of the primary outcome than recruitment in 1999 to 2005. Conclusions Among octogenarians, over 2 decades, risk factor prevalence increased, management strategies improved, and survival remained stable, but the proportion hospitalized for cardiovascular causes declined. Despite increasing clinical complexity, in cardiology settings the burden of hospitalizations in the oldest old with chronic HF is declining (AU)


Subject(s)
Humans , Male , Female , Aged, 80 and over , Heart Failure/therapy , Heart Failure/mortality , Treatment Outcome , Follow-Up Studies , Chronic Disease , Echocardiography , Prognosis
3.
Oncoimmunology ; 6(11): e1356151, 2017.
Article in English | MEDLINE | ID: mdl-29147611

ABSTRACT

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.

4.
Plant Biol (Stuttg) ; 18(6): 1016-1024, 2016 Nov.
Article in English | MEDLINE | ID: mdl-27487981

ABSTRACT

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.


Subject(s)
Calcium Oxalate/metabolism , Calcium/metabolism , Glycine max/metabolism , Microscopy, Electron, Scanning , Plant Leaves/chemistry , Plant Leaves/metabolism , Plant Leaves/ultrastructure , Soil/chemistry , Glycine max/chemistry , Glycine max/ultrastructure
5.
Plant Biol (Stuttg) ; 18(6): 1025-1030, 2016 Nov.
Article in English | MEDLINE | ID: mdl-27488096

ABSTRACT

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.


Subject(s)
Poaceae/metabolism , Silicon Dioxide/metabolism , Organ Specificity , Plant Leaves/chemistry , Plant Leaves/metabolism , Plant Leaves/ultrastructure , Plant Roots/chemistry , Plant Roots/metabolism , Plant Roots/ultrastructure , Poaceae/chemistry , Poaceae/ultrastructure , Seedlings/chemistry , Seedlings/metabolism , Seedlings/ultrastructure
6.
J Biol Regul Homeost Agents ; 27(1): 105-19, 2013.
Article in English | MEDLINE | ID: mdl-23489691

ABSTRACT

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.


Subject(s)
Apoptosis/drug effects , Breast Neoplasms/pathology , Curcumin/pharmacology , Mammary Neoplasms, Animal/pathology , Receptor, ErbB-2/metabolism , Animals , Breast Neoplasms/drug therapy , Cell Cycle/drug effects , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival/drug effects , Curcumin/adverse effects , Curcumin/therapeutic use , Drug Screening Assays, Antitumor , Female , Fibroblasts/drug effects , Fibroblasts/metabolism , Fibroblasts/pathology , Humans , MAP Kinase Signaling System/drug effects , Mammary Neoplasms, Animal/blood , Mammary Neoplasms, Animal/drug therapy , Mice , Mice, Inbred BALB C , Mice, Transgenic , NIH 3T3 Cells , Phosphorylation/drug effects , Poly(ADP-ribose) Polymerases/metabolism , Rats , Receptor, ErbB-2/genetics , bcl-2-Associated X Protein/metabolism
7.
Osteoporos Int ; 21(8): 1323-30, 2010 Aug.
Article in English | MEDLINE | ID: mdl-19809775

ABSTRACT

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.


Subject(s)
Hip Fractures/epidemiology , Osteoporotic Fractures/epidemiology , Age Distribution , Aged , Diagnosis-Related Groups , Female , Health Care Costs/statistics & numerical data , Hip Fractures/rehabilitation , Hospitalization/statistics & numerical data , Hospitalization/trends , Humans , Incidence , Italy/epidemiology , Male , Middle Aged , Osteoporotic Fractures/rehabilitation , Sex Distribution
8.
Cir. Esp. (Ed. impr.) ; 80(1): 3-8, jul. 2006. tab
Article in Es | IBECS | ID: ibc-046096

ABSTRACT

El insulinoma es la neoplasia más frecuente del grupo de tumores neuroendocrinos de páncreas. En el presente estudio se evaluaron los resultados clínicos e inmunohistoquímicos de 20 casos de pacientes tratados quirúrgicamente desde enero de 1986 hasta diciembre de 2004. Se describió el cuadro clínico, los exámenes de laboratorio e imageneológicos, y se hizo énfasis en los aspectos quirúrgicos, las complicaciones y el seguimiento a medio y largo plazo. La cirugía se indicó sobre la base de las evidencias clínicas y analíticas de hipoglucemia e hiperinsulinemia. En 15 pacientes se logró la localización previa de la lesión, en 5, su localización fue identificada durante la cirugía mediante la palpación y a través del ultrasonido intraoperatorio. Los procedimientos quirúrgicos realizados con más frecuencia fueron la resección pancreática en la mitad de los pacientes y la enucleación por laparotomía en la otra mitad. En 2 pacientes se utilizó la vía laparoscópica. Dos presentaron tardíamente diabetes mellitus. La complicación quirúrgica más frecuente fue la fístula pancreática en 13 de los casos. No hubo mortalidad en la presente serie. En la totalidad de los pacientes se obtuvo la reversión clínica de los síntomas, caracterizada por la desaparición de la tríada de Whipple, además de la normalización o el aumento de los valores de glucemia, comparados con los valores del preoperatorio (AU)


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 (AU)


Subject(s)
Male , Female , Adult , Middle Aged , Adolescent , Humans , Insulinoma/diagnosis , Insulinoma/surgery , Neuroendocrine Tumors/surgery , Immunohistochemistry/methods , Laparotomy/methods , Blood Glucose/analysis , Pancreatectomy/methods , Pancreatic Neoplasms/diagnosis , Pancreatic Neoplasms/surgery , Pancreas/pathology , Pancreas/surgery , Hypoglycemia/complications , Hypoglycemia/diagnosis , Clinical Laboratory Techniques/trends , Topography, Medical/methods , Abdomen , Splenectomy/methods
9.
Cir Esp ; 80(1): 3-8, 2006 Jul.
Article in Spanish | MEDLINE | ID: mdl-16796946

ABSTRACT

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.


Subject(s)
Insulinoma , Pancreatic Neoplasms , Adolescent , Adult , Aged , Female , Humans , Insulinoma/pathology , Insulinoma/surgery , Male , Middle Aged , Pancreatic Neoplasms/pathology , Pancreatic Neoplasms/surgery
11.
Tissue Eng ; 6(1): 39-44, 2000 Feb.
Article in English | MEDLINE | ID: mdl-10941199

ABSTRACT

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.


Subject(s)
Cell Culture Techniques/methods , Liver/cytology , Albumins/metabolism , Animals , Biocompatible Materials , Biomedical Engineering , Cell Survival , Cell Transplantation , Liver/physiology , Liver Transplantation , Microscopy, Electron, Scanning , Perfusion , Polyglycolic Acid , Rats
12.
Tissue Eng ; 5(6): 525-32, 1999 Dec.
Article in English | MEDLINE | ID: mdl-10611544

ABSTRACT

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.


Subject(s)
Biocompatible Materials , Cell Transplantation/instrumentation , Implants, Experimental , Muscle, Skeletal/cytology , Polyglycolic Acid , Polymers , Surgical Mesh , Actins/analysis , Animals , Biodegradation, Environmental , Biomarkers , Desmin/analysis , Female , Graft Survival , Male , Omentum , Rats , Rats, Inbred F344 , Transplantation, Heterotopic
13.
J Surg Res ; 87(1): 6-13, 1999 Nov.
Article in English | MEDLINE | ID: mdl-10527698

ABSTRACT

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.


Subject(s)
Anastomosis, Surgical , Cell Transplantation , Intestine, Small/cytology , Intestine, Small/surgery , Animals , Intestinal Mucosa/pathology , Rats , Rats, Inbred Lew
14.
Tissue Eng ; 5(4): 339-46, 1999 Aug.
Article in English | MEDLINE | ID: mdl-10477856

ABSTRACT

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.


Subject(s)
Anastomosis, Surgical/methods , Artificial Organs , Intestinal Mucosa/cytology , Intestinal Mucosa/surgery , Intestine, Small/surgery , Animals , Animals, Newborn , Biocompatible Materials , Biomedical Engineering , Cell Transplantation , Female , Intestinal Mucosa/physiology , Lactic Acid , Male , Omentum , Polyesters , Polyglycolic Acid , Polymers , Rats , Rats, Inbred Lew
17.
J Pediatr Surg ; 34(1): 124-8, 1999 Jan.
Article in English | MEDLINE | ID: mdl-10022156

ABSTRACT

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.


Subject(s)
Blood Vessel Prosthesis , Cell Transplantation , Intestinal Mucosa , Liver Circulation , Liver/cytology , Portal System , Animals , Cell Culture Techniques , Jejunum , Liver, Artificial , Male , Rats , Rats, Inbred Lew
18.
Transplantation ; 67(2): 227-33, 1999 Jan 27.
Article in English | MEDLINE | ID: mdl-10075585

ABSTRACT

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.


Subject(s)
Biocompatible Materials , Intestinal Mucosa/physiology , Intestinal Mucosa/transplantation , Intestine, Small/physiology , Intestine, Small/transplantation , Organoids/physiology , Transplantation, Isogeneic/physiology , Animals , Animals, Newborn , Body Weight , Cysts/diagnostic imaging , Cysts/pathology , Hepatectomy , Image Processing, Computer-Assisted , Intestinal Mucosa/cytology , Male , Neovascularization, Physiologic , Organoids/ultrastructure , Polyglycolic Acid , Portacaval Shunt, Surgical , Rats , Rats, Inbred Lew , Regeneration , Signal Transduction , Transplantation, Isogeneic/methods , Ultrasonography
19.
Transplantation ; 67(2): 241-5, 1999 Jan 27.
Article in English | MEDLINE | ID: mdl-10075587

ABSTRACT

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.


Subject(s)
Anastomosis, Surgical/methods , Biopolymers , Intestinal Mucosa/surgery , Intestinal Mucosa/transplantation , Intestine, Small/surgery , Intestine, Small/transplantation , Transplantation, Isogeneic/methods , Animals , Animals, Newborn , Cysts , Female , Intestinal Mucosa/physiology , Intestine, Small/physiology , Male , Organoids/ultrastructure , Polyglycolic Acid , Rats , Rats, Inbred Lew , Transplantation, Isogeneic/pathology , Transplantation, Isogeneic/physiology
20.
Recenti Prog Med ; 84(11): 765-7, 1993 Nov.
Article in Italian | MEDLINE | ID: mdl-8290788

ABSTRACT

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.


Subject(s)
Aorta , Cardiomyopathies/diagnosis , Mitral Valve Prolapse/etiology , Sarcoidosis/diagnosis , Adult , Humans , Male , Sarcoidosis/complications
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