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1.
J Endocrinol Invest ; 44(10): 2071-2102, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33956331

RESUMO

PURPOSE: Infertility represents a peculiar social burden affecting more than 15% of couples, provoking it a real threat to the general quality of life and to the sexual health. The medicalization (diagnosis, therapy and follow up) of the lack of fertility is frequently a challenge in term of personal and couple's involvement. In particular, while the Assisted Reproductive Technology (ART) has allowed many infertile couples to achieve pregnancy, the therapeutic process faced by the couple bears a strong psychological stress that can affect the couple's quality of life, relationship and sexuality. Despite infertility affects both female and male sexual health, only recently the interest in the effects of ART on the couple's sexuality has grown, especially for women. METHODS: A literature research on the sexual dysfunction in fertility care and particularly in ART setting was performed. RESULTS: Literature largely found that intimacy and sexuality appear specifically impaired by intrusiveness of treatments and medical prescriptions. Moreover, there is a close relationship between emotional, psychological and sexual aspects, which can be integrated in the new concept of Inferto-Sex Syndrome (ISS) that can impair the ART treatment outcomes. Evidence demonstrates that the assessment of sexual function is necessary in couples undergoing diagnosis of infertility and ART. CONCLUSION: A close relationship between infertility and sexuality, both in the female and male partners, was detected. ART treatments may heavily impact on the couple's psychosexual health. A couple-centred program for the integrated management of psychological and sexual dysfunction should be considered in the context of ART programs.


Assuntos
Infertilidade/patologia , Reprodução , Técnicas de Reprodução Assistida/estatística & dados numéricos , Disfunções Sexuais Fisiológicas/complicações , Estresse Psicológico/complicações , Feminino , Humanos , Infertilidade/etiologia , Masculino , Gravidez
2.
Neurochirurgie ; 66(6): 477-483, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33091460

RESUMO

Non-small cell lung cancer (NSCLC) is frequently associated with central nervous system metastases resulting in poor outcomes. As newer targeted therapies become available determining which patients can benefit from these therapies has remained challenging, and current molecular testing options rely on a panel of only a handful of known oncogenic drivers. Here, we demonstrate a targeted approach at uncovering clinically relevant variants in cancer-associated genes using genomic sequencing. Our patient underwent targeted sequencing of 212 cancer-associated genes, revealing mutations in six; two of which were in EGFR, an important target for therapy in NSCLC. A multidisciplinary approach involving surgical resection, radiation, and targeted therapy based on the genomic profile and tumor pathology ultimately lead to positive therapeutic response and stable disease. Our report provides a proof of principle for incorporating higher throughput genomic sequencing techniques directly into patient care. We also report an atypical response of an EGFR mutation positive metastatic tumor to immune checkpoint therapy, despite recent reports suggesting that these patients do not benefit from immune checkpoint inhibitors. A brief review of current literature is discussed here to explore links between EGFR mutations and PD-L1 expression, as well as response to targeted therapies.


Assuntos
Neoplasias Encefálicas/genética , Neoplasias Encefálicas/secundário , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/secundário , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Antígeno B7-H1/genética , Neoplasias Encefálicas/cirurgia , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Terapia Combinada , Receptores ErbB/genética , Humanos , Inibidores de Checkpoint Imunológico/uso terapêutico , Imunoterapia , Masculino , Pessoa de Meia-Idade , Mutação/genética , Procedimentos Neurocirúrgicos/métodos , Fumar
3.
Neurochirurgie ; 66(5): 391-395, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32502563

RESUMO

BACKGROUND: Central Neurocytomas (CNs) are rare brain tumors, making up less than 1% of all primary tumors within the CNS. They are commonly located in the lateral ventricles, and often present with visual changes and symptoms of obstructive hydrocephalus. Histopathology shows characteristics similar to ependymomas and oligodendrogliomas, however tumor cells display neuronal differentiation, and immunohistochemical stains typically for synaptophysin. Gross total resection is the most important prognostic indicator of survival. CASE DESCRIPTION: We describe the case of a 48-year-old male with a CN originating in the third ventricle with expansion through the cerebral aqueduct into the fourth ventricle. He presented with bi-frontal headaches, imaging revealed an avidly enhancing tumor occupying the inferior third ventricle, cerebral aqueduct, with expansion into the fourth ventricle. An interhemispheric craniotomy with a transcallosal transchoroidal approach to the third ventricle was performed, this provided a trajectory that paralleled the long axis of the tumor. Postoperative imaging confirmed a near total resection with linear residual enhancement on the anterior wall of the fourth ventricle. Intensity modulated radiotherapy was performed, 7-month follow-up imaging was clean. CONCLUSION: CNs are rare brain tumors, most commonly located within the lateral ventricles. We describe a rare case of a CN spanning from the third ventricle into the cerebral aqueduct and fourth ventricle. To our knowledge, this is only the fourth reported case of such a tumor. Surgical approach must be carefully selected, as gross total resection is the most important prognostic indicator.


Assuntos
Aqueduto do Mesencéfalo/patologia , Neoplasias do Ventrículo Cerebral/patologia , Neoplasias do Ventrículo Cerebral/cirurgia , Quarto Ventrículo/patologia , Neurocitoma/patologia , Neurocitoma/cirurgia , Procedimentos Neurocirúrgicos/métodos , Terceiro Ventrículo/patologia , Aqueduto do Mesencéfalo/diagnóstico por imagem , Neoplasias do Ventrículo Cerebral/radioterapia , Plexo Corióideo/anatomia & histologia , Plexo Corióideo/cirurgia , Terapia Combinada , Corpo Caloso/anatomia & histologia , Corpo Caloso/cirurgia , Craniotomia , Quarto Ventrículo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neurocitoma/radioterapia , Terceiro Ventrículo/diagnóstico por imagem , Resultado do Tratamento
4.
Andrology ; 6(3): 385-395, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29600532

RESUMO

Sertoli cells are located in the testes where they control several key functions in spermatogenesis. Over the past 30 years, Sertoli cells have been upgraded from a simple scaffold-like structural system to a dynamic functional system of intercellular support that delivers potent immunomodulatory and trophic factors. Since the discovery of new Sertoli cell secretory products, these cells have been utilized in experimental cell transplantation and co-transplantation protocols aimed at treating both chronic inflammatory and degenerative disorders. For these reasons, this work reviews the application of both naked and microencapsulated Sertoli cells used in cell transplantation studies of several chronic or autoimmune diseases such as diabetes mellitus, Laron dwarfism, and Duchenne muscular dystrophy and in studies aimed at the prevention of skin allograft rejection.


Assuntos
Células de Sertoli/fisiologia , Células de Sertoli/transplante , Animais , Humanos , Masculino
5.
Andrology ; 5(2): 268-273, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28125168

RESUMO

The association between inflammation of the male reproductive system and oligozoospermia has been frequently reported in the clinical work-up of male infertility. To improve sperm parameters in infertile patients with genital inflammation, many phytochemical and nutraceutical drugs are currently being used. However, their use is still empirical and no conclusive data have been provided about their efficacy. The treatment with steroid anti-inflammatory drugs might be useful in reducing inflammation and improving sperm parameters, thus increasing the fertility outcome. The aim of this study was to evaluate if glucocorticoid treatment improves seminal parameters in infertile oligozoospermic patients presenting signs of accessory gland inflammation at genital ultrasound. A total of 90 infertile patients were enrolled in the study. They presented normal testicular volume, normal FSH plasma levels, the presence of various degrees of oligozoospermia, associated with scrotal and trans-rectal ultrasound signs indicative of accessory gland inflammation, but negative microbiological analysis on semen and/or prostatic secretions. Patients were randomly allocated into three groups of treatment, receiving, respectively, 5, 12.5, and 25 mg daily oral Prednisone for one month. Seminal parameters were evaluated at admission and after treatment. In patients undergoing Prednisone treatment at a daily dose of 5 mg we observed a significant increase in total sperm count. At a daily dose of 12.5 mg, Prednisone treatment improved sperm concentration, total sperm count, and the percentage of sperm motility. Twenty-five mg of Prednisone led to significant improvement in all the sperm parameters, except for semen volume. These results clearly demonstrate that Prednisone treatment can significantly improve sperm parameters in a selected population of oligozoospermic patients. These findings suggest that Prednisone treatment should be considered in idiopathic oligozoospermic patients with supposed normal spermatogenesis and accessory gland inflammatory alterations, in order to improve sperm parameters and fertility outcome.


Assuntos
Anti-Inflamatórios/uso terapêutico , Infertilidade Masculina/dietoterapia , Inflamação/tratamento farmacológico , Oligospermia/tratamento farmacológico , Prednisona/uso terapêutico , Adulto , Anti-Inflamatórios/administração & dosagem , Humanos , Infertilidade Masculina/diagnóstico por imagem , Inflamação/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Oligospermia/diagnóstico por imagem , Prednisona/administração & dosagem , Análise do Sêmen , Contagem de Espermatozoides , Motilidade dos Espermatozoides/efeitos dos fármacos , Testículo/diagnóstico por imagem , Resultado do Tratamento , Adulto Jovem
6.
Minerva Endocrinol ; 40(4): 267-82, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26398188

RESUMO

Pancreatic islet cell transplantation has represented the mainstay of cell therapy for the potential, final cure of type 1 diabetes mellitus (T1D), along the past two decades. Unfortunately, the restricted availability of cadaveric human donor pancreases coupled with heavy side effects of the recipient's general immunosuppression, have severely crippled progress of this approach into clinical trials. Only a few excellence centers, worldwide, have thus far accrued still quite marginal clinical success. In an attempt to overcome the limits of islet transplantation new technologies for use of several stem cell lineages are being under investigation, with initial experimental evidence of success. Essentially, the actual lines of research involve attempts to either activate native endogenous stem cells that replace diseased/dead cells, by a cell regeneration process, or condition other stem cells to acquire the functional properties of the targeted cells to be substituted (i.e., beta-cell-like elements associated with insulin secretory competence). A wide array of stem cells may fulfill this task, from embryonic (whose use still faces strong ethical barriers), to adult, to induced pluripotent stem cells. Mesenchymal adult stem cells, retrievable from many different sites, including adipose tissue, bone marrow and post-partum umbilical cord Wharton Jelly, seem to couple plastic to immunoregulatory properties that might greatly help progress for the disease cure.


Assuntos
Diabetes Mellitus Tipo 1/terapia , Transplante das Ilhotas Pancreáticas/métodos , Transplante de Células-Tronco/métodos , Humanos
7.
J Control Release ; 192: 249-61, 2014 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-25111130

RESUMO

Neonatal porcine Sertoli cells (NPSC) are immune privileged cells showing innate phagocytic and antibacterial activities. NPSC have been shown capable of immunoaltering the body's response and possess lung homing capacity. These properties encourage investigation of NPSC as functional components of cell-based therapeutic protocols to treat lung infections and related complications. In this work, for the first time, NPSC were tailored to carry an antibiotic drug loaded into poly(d,l lactic) acid microparticles (MP). A loading protocol was developed, which afforded 30% drug uptake and high stability over time, with little or no effects on NPSC viability, morphology, reactive oxygen species production and DNA integrity. FSH receptor integrity, and TGFß (transforming growth factor ß) and AMH (anti-Müllerian hormone) expressions were unchanged after 1month of cryopreservation. Protein tyrosine kinase activation due to phagocytosis may have had resulted in changes in inhibin B expression. The activity of MP-loaded or NPSC alone against Pseudomonas aeruginosa was maintained throughout 1month of storage. NPSC couple an innate antibacterial activity with the capacity to embody drug loaded MP. We showed for the first time that engineered NPSC can be cryopreserved with no loss of their basic properties, thereby possibly representing a novel approach for cell-based therapeutic and drug delivery system.


Assuntos
Antibacterianos/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Ofloxacino/administração & dosagem , Células de Sertoli/citologia , Animais , Antibacterianos/farmacologia , Células Cultivadas , Criopreservação , Masculino , Ofloxacino/farmacologia , Infecções por Pseudomonas/tratamento farmacológico , Pseudomonas aeruginosa/efeitos dos fármacos , Células de Sertoli/metabolismo , Suínos
8.
Transplant Proc ; 46(6): 1999-2001, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25131093

RESUMO

Insulin resistance in type 2 diabetes mellitus (T2DM) may be due to a chronic inflammation of the visceral adipose tissue (VAT) leading to local and systemic increases in proinflammatory cytokines. Microencapsulated porcine Sertoli cells (MC-pSC), by provision of immunomodulatory and trophic factors, have been successfully used to reduce such inflammation in rodent animal models of type 1 diabetes with no complications or deleterious side effects. Herein, we have begun to investigate this novel and safe therapeutic approach in the spontaneously obese nonhuman primate with spontaneous, insulin-dependent T2DM. After MC-pSC intraperitoneal injection we have evaluated, throughout a 6-month follow-up period, daily ad libitum fed glucose levels, daily exogenous insulin supplementation, biweekly body weight measurements, periodic fasting blood glucose concentrations, glycated hemoglobin (HbA1c) levels, glucose tolerance tests (GTT), and fluorescence-activated cell sorting cytometry (FACS) assessment of peripheral blood mononuclear cells. Very preliminarily, we have observed a slight reduction in fasting (FPG) and mean nonfasting (NF) plasma glucose levels. We found minimal changes, only in 1 animal, in daily exogenous insulin requirements and HbA1c levels. Flow cytometric analysis was associated with decrease in CD8(+) cells only in 1 recipient with a reduction in mean regulatory T Cells (Treg), whereas interestingly, decrease of B lymphocytes was observed in both animals. These results may suggest that this novel MC-SC-based transplantation protocol might possibly impact the metabolic status of T2DM in higher mammals that are close to humans.


Assuntos
Terapia Baseada em Transplante de Células e Tecidos/métodos , Diabetes Mellitus Tipo 2/terapia , Células de Sertoli/transplante , Transplante Heterólogo , Animais , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/etiologia , Composição de Medicamentos , Hemoglobinas Glicadas/metabolismo , Hipoglicemiantes/uso terapêutico , Injeções Intraperitoneais , Insulina/uso terapêutico , Resistência à Insulina/fisiologia , Macaca mulatta , Masculino , Obesidade/complicações , Suínos
9.
J Biol Regul Homeost Agents ; 27(3): 805-16, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24152845

RESUMO

Cadmium (Cd), an ubiquitous environmental metal, mainly used for industrial purposes, may be toxic at level of the reproductive system. Testis tubular-based Sertoli cells (SC), play a major role in constituting the blood-testis barrier and provide a unique microenvironment for the genesis and differentiation of germ cells. Hence SC strictly control sperm qualitative and quantitative parameters. We aimed to assess whether exposure to Cd would adversely affect superior mammal SC viability and function. We isolated and purified SC from pre-pubertal pig testes according to our method and incubated the retrieved cells with three different Cadmium chloride concentrations (5-10-15 microM). Parameters of SC function such as inhibin B and anti-Mullerian hormone (AMH) were depressed by Cd exposure, contrary to what observed in untreated controls. No impairment of the FSH receptor integrity on the SC, as assessed by 17-beta-estradiol production, upon stimulation with FSH, was observed in either 5 microM Cd-treated or untreated controls. Differences, on the contrary, were observed for higher Cd concentrations (10 and 15 mM), in terms of FSH receptor integrity, that was altered, as compared to untreated controls, in terms of lower production of 17-beta-estradiol. In addition, the apoptotic test showed a significant increase of early (ANNEXIN V-/Propidium Iodide+) (AV-/PI+) and late apoptotic cells (AV+/ PI+) in all Cd -treated SC conditions as compared to controls. In conclusion, the Cd -related toxicity on SC, clearly demonstrated by our study, even at low concentrations, is expected to damage spermatogenesis that directly is dependent upon retention of SC viability and function.


Assuntos
Cádmio/toxicidade , Células de Sertoli/efeitos dos fármacos , Animais , Hormônio Antimülleriano/metabolismo , Apoptose/efeitos dos fármacos , Cádmio/farmacocinética , Sobrevivência Celular/efeitos dos fármacos , Inibinas/metabolismo , Masculino , Receptores do FSH/efeitos dos fármacos , Receptores do FSH/fisiologia , Células de Sertoli/fisiologia , Suínos
10.
J Endocrinol Invest ; 36(7): 527-30, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23612476

RESUMO

AIMS: Polycystic ovary syndrome (PCOS) is frequently observed in women of reproductive age, and is associated with disturbances in both reproductive and metabolic function. Insulin resistance (IR) is key to the pathophysiology of PCOS, and early detection may improve outcomes in this patient group. Rapid and straightforward laboratory tests may contribute towards early detection. METHODS: A retrospective chart review of 185 women presenting for the first time to a gynecology clinic was carried out. Of this group, 77 met the inclusion criteria. The sample was divided according to insulin sensitivity (IS) given by the Matsuda Index, and the two groups were compared using correlation analysis. Furthermore, the sensitivity and specificity of the Matsuda, homeostasis model assessment of IR (HOMA-IR) and quantitative insulin sensitivity check index (QUICKI) indexes were compared. RESULTS: Although bodu mass index (BMI) was higher in the insulin resistant group than the insulin sensitive group, the mean age of the IR group was actually lower. HOMA-IR and QUICKI correlated well with the Matsuda index in both groups. The HOMA-IR test showed the highest sensitivity and specificity in the detection of IR when compared to the Matsuda Index, and no added benefit was derived from using a combination of both QUICKI and HOMA- 1R. CONCLUSIONS: In a group of 77 women diagnosed with PCOS, 49 (63.6%) had IR according to the Matsuda index. The HOMA-IR index, which is based on fasting serum insulin and glucose, correlated closely with the Matsuda index, indicating it may be a reliable substitute in the detection and subsequent early intervention required to improve outcomes in PCOS.


Assuntos
Glicemia/análise , Homeostase , Resistência à Insulina , Insulina/sangue , Síndrome do Ovário Policístico/diagnóstico , Adolescente , Adulto , Índice de Massa Corporal , Criança , Diagnóstico Precoce , Feminino , Humanos , Modelos Biológicos , Síndrome do Ovário Policístico/sangue , Estudos Retrospectivos , Sensibilidade e Especificidade
12.
J Biomater Appl ; 23(2): 123-45, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18467747

RESUMO

The optimization, through a Design of Experiments (DoE) approach, of a microencapsulation procedure for isolated neonatal porcine islets (NPI) is described. The applied method is based on the generation of monodisperse droplets by a vibrational nozzle. An alginate/polyornithine encapsulation procedure, developed and validated in our laboratory for almost a decade, was used to embody pancreatic islets. We analyzed different experimental parameters including frequency of vibration, amplitude of vibration, polymer pumping rate, and distance between the nozzle and the gelling bath. We produced calcium-alginate gel microbeads with excellent morphological characteristics as well as a very narrow size distribution. The automatically produced microcapsules did not alter morphology, viability and functional properties of the enveloped NPI. The optimization of this automatic procedure may provide a novel approach to obtain a large number of batches possibly suitable for large scale production of immunoisolated NPI for in vivo cell transplantation procedures in humans.


Assuntos
Alginatos/química , Materiais Biocompatíveis/química , Técnicas de Cultura de Células/instrumentação , Transplante de Células/métodos , Transplante das Ilhotas Pancreáticas/métodos , Ilhotas Pancreáticas/citologia , Animais , Animais Recém-Nascidos , Cápsulas , Técnicas de Cultura de Células/métodos , Sobrevivência Celular , Transplante de Células/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Transplante das Ilhotas Pancreáticas/instrumentação , Teste de Materiais , Coelhos , Suínos , Vibração
13.
Transplant Proc ; 40(2): 419-21, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18374087

RESUMO

Pdx-1 genetically engineered FH-B-TPN cells might represent a source for insulin-secreting cells. We then have tested whether poly-L-lysine (PLL) and collagen (C) exposure in vitro promote three-dimensional particle formation and differentiation toward an endocrine cell phenotype. On these matrices, we observed that FH-B-TPN cells showed a tendency to either aggregate when seeded on PLL or to form uniform cell monolayers, but not to aggregate on C. While insulin was released in any condition, GSIR was only associated with PLL mainly at 24 and 72 hours of culture. Various culture matrices influenced the expression of glucose transporter type 2 and gluco kinase, being they expressed more intensively on PLL rather than C or in controls. mRNA expression for NeuroD/Beta2, Isl-1, Ras, Metalloproteinase-2 (MMP-2), -9 and -7 also were affected, with PLL inducing increased expression of NeuroD/Beta2 of Isl-1, and no difference between C and control. PLL, unlike C, strongly increased Ras through observation times. MPP-2 and -9 were decreased by both PLL and C, whereas MMP-7 was increased by PLL. PLL, usually employed to promote culture cell adhesion, has been proven capable to stimulate pancreatic endocrine function and cell aggregation and to stimulate gene expression of key markers for either insulin transcription or MMP-7.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Colágeno/farmacologia , Ilhotas Pancreáticas/citologia , Ilhotas Pancreáticas/fisiologia , Polilisina/farmacologia , Agregação Celular , Regulação da Expressão Gênica/efeitos dos fármacos , Engenharia Genética , Humanos , Insulina/análise , Insulina/metabolismo , Secreção de Insulina , Ilhotas Pancreáticas/metabolismo , Fenótipo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
14.
Transplant Proc ; 40(2): 427-9, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18374090

RESUMO

Replacement beta cells may be generated from stem/progenitor cells, possibly residing within the pancreatic islet cells. We sought to investigate the possible use of human islet (HI)-derived cell monolayers as a possible source for beta cells. These cells could be propagated in vitro and potentially induced to acquire glucose-stimulated insulin release (GSIR) ability. Loss of three-dimensional architecture, following monolayer establishment, resulted in either rearrangement of both pancreatic hormone expression and key transcription factors or decrease in insulin production or GSIR disappearance. We showed that cell deregulation/dedifferentiation was reversible by treating the cell monolayers, after five passages with streptozotocin (STZ), a well-known beta-cell toxin. When used at subtoxic concentrations, STZ promoted differentiation of HI-derived cell monolayers and GSIR recovery. This effect allowed production of insulin-secreting cells starting from cell monolayers doubled five times in vitro, meaning a 400-fold increase in the cellular starting material. Such islet cell expansion capability in vitro might elucidate a new source of insulin-secreting cells thereby possibly overcoming the problem posed by searching for human organ donation.


Assuntos
Ilhotas Pancreáticas/citologia , Estreptozocina/farmacologia , Cadáver , Técnicas de Cultura de Células/métodos , Diferenciação Celular , Divisão Celular , Células Cultivadas , Humanos , Insulina/metabolismo , Secreção de Insulina , Ilhotas Pancreáticas/efeitos dos fármacos , Ilhotas Pancreáticas/fisiologia , Fenótipo , Doadores de Tecidos
15.
J Biomed Mater Res A ; 83(1): 216-24, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17607741

RESUMO

Alginate encapsulation is one of the most widely used techniques for introducing cell-based therapeutics into the body. Numerous encapsulation methodologies exist, utilizing a variety of alginates, purification technologies, and unique polycationic membrane components. The stability of a conventional alginate formulation encapsulated using a commercially available technique and apparatus has been characterized extensively. The current study employs an encapsulation protocol and ultra-pure alginate pioneered at the University of Perugia. The enhanced microcapsules were produced, characterized, and implanted into the brain, peritoneal cavity, and subcutaneous space of Long-Evans rats. After 14, 28, 60, 90, 120, and 180 or 215 days, capsules were explanted and the surface was analyzed using Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). Image analysis was carried out to measure changes in diameter and wall thickness. FTIR peak analysis and surface morphology from SEM indicated that the enhanced encapsulation technique and formulation produced a stable biocapsule capable of survival in all sites, including the harsh peritoneal environment, for at least 215 days. Preimplant analysis showed a marked increase in the structural integrity of the enhanced formulation with improved elasticity and burst strength compared with the baseline formulation, which remained stable for less than 60 days. The enhanced microcapsule composition showed advantages in physical strength and longevity, indicating that small changes in encapsulation methodologies and materials selection can dramatically impact the stability and longevity of alginate microcapsules and their contents.


Assuntos
Alginatos/química , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/metabolismo , Cápsulas/síntese química , Cápsulas/metabolismo , Teste de Materiais/métodos , Peptídeos/química , Alginatos/metabolismo , Animais , Materiais Biocompatíveis/química , Cápsulas/química , Cromatografia em Gel , Ácido Glucurônico/química , Ácido Glucurônico/metabolismo , Ácidos Hexurônicos/química , Ácidos Hexurônicos/metabolismo , Luz , Masculino , Peptídeos/metabolismo , Peritônio/ultraestrutura , Próteses e Implantes , Ratos , Ratos Long-Evans , Espalhamento de Radiação , Espectroscopia de Infravermelho com Transformada de Fourier
16.
Transplant Proc ; 38(4): 1156-7, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16757293

RESUMO

To comply with regulatory restrictions, with regard to graft of human islets immunoprotected within artificial microcapsules, into patients with type 1 diabetes mellitus (T1DM) with no recipient immunosuppression, we have prepared standard protocols on: (1) sodium alginate purification (clinical grade) for microcapsule fabrication; (2) preparation of biocompatible and permselective microcapsules containing human islets; and (3) minimally invasive techniques for grafting of the encapsulated human islets into the recipients' peritoneal cavity. As to no. 1, starting from pharmaceutical grade, raw sodium alginate powder, we prepared a pyrogen- and endotoxin-free 1.6% alginate solution by means of dialysis, multiple filtrations, and dilution/osmolality adjustments. As to no. 2, we have selected human islet preparations associated with >80% purity/viability, which underwent careful functional quality control testing prior to encapsulation; namely, most capsules contained one islet. As for no. 3, we have devised a simple intraperitoneal injection method under abdominal echography guidance with only local anesthesia to deposit the encapsulated islets in saline within the peritoneal leaflets. These technical protocols were officially approved by the Italian Ministry of Health which has released permission to conduct a phase I, closed human trial in 10 patients using encapsulated human islet grafts into nonimmunosuppressed patients with T1DM.


Assuntos
Cápsulas , Diabetes Mellitus Tipo 1/cirurgia , Transplante das Ilhotas Pancreáticas/métodos , Ensaios Clínicos Fase I como Assunto , Humanos , Terapia de Imunossupressão , Ilhotas Pancreáticas/citologia , Ilhotas Pancreáticas/fisiologia , Transplante das Ilhotas Pancreáticas/imunologia , Itália , Coleta de Tecidos e Órgãos/métodos
17.
Cell Transplant ; 15(1): 55-65, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16700330

RESUMO

Human islet allografts are well known to induce full and sustained remission of hyperglycemia, with complete normalization of key metabolic parameters. Nevertheless, acquiring human islets, even from cadaveric human donor pancreases, remains a significant impediment to successful transplantation therapy for diabetes. To overcome this difficulty, neonatal porcine cell clusters (NPCCs) have been considered for human islet substitutes because they are easily obtained by collagenase digestion of the neonatal piglet pancreas. Currently, the major hurdle in using NPCCs for xenograft is the delay (time lag) in achieving the posttransplant normalization of blood glucose levels in animal diabetic recipients. The present work is the first attempt to evaluate whether incubation of NPCCs in simulated microgravity, in the presence or absence of Sertoli cells (SC), may reduce the maturation time lag of beta-cells by differentiation acceleration in vitro, thereby expediting production, viability, and acquisition of functional competence of pretransplantation beta-cell-enriched islets. Following a 3-day incubation period, NPCCs maintained in conventional culture, NPCCs incubated in simulated microgravity in the HARV biochamber, and NPCCs plus co-incubated SC in simulated microgravity were examined for viability, morphology, and insulin secretion. Results show that NPCCs grown alone in the HARV biochamber are superior in quality, both in terms of viability and functional competence, when compared to other culture pretreatment protocols. This finding strongly suggests that NPCC pretreatment in simulated microgravity may enhance the transplantation success of NPCCs in the diabetic recipient.


Assuntos
Ilhotas Pancreáticas , Células de Sertoli/citologia , Simulação de Ausência de Peso , Animais , Animais Recém-Nascidos , Sobrevivência Celular/fisiologia , Células Cultivadas , Técnicas de Cocultura , Glucose/química , Imuno-Histoquímica , Insulina/metabolismo , Secreção de Insulina , Ilhotas Pancreáticas/citologia , Ilhotas Pancreáticas/fisiologia , Ilhotas Pancreáticas/ultraestrutura , Masculino , Microscopia Eletrônica , Células de Sertoli/ultraestrutura , Suínos
18.
Transplant Proc ; 37(8): 3505-8, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16298643

RESUMO

BACKGROUND: A nonhuman primate model of diabetes is valuable for assessing porcine pancreatic islet transplants that might have clinical benefits in humans. METHODS: Neonatal porcine islets, microencapsulated in alginate-polyornithine-alginate, were injected intraperitoneally (10,000 IEQs/kg islets) into eight adult male cynomolgus monkeys rendered diabetic with streptozotocin. Eight diabetic controls were given an equivalent dose of empty placebo capsules. All subjects received a repeat transplant 3 months after the first. RESULTS: The transplant was well tolerated and no adverse or hypoglycemic events occurred. There were two deaths from nontransplant treatment or diabetic complications unrelated to the transplants. After transplantation, the average insulin dose was reduced in the islet-treated group and increased in the control group. At 12 weeks after the first transplant there was a mean 36% (95% CI: 6% to 65%, P = .02) drop in daily insulin dose compared with the control group. After 24 weeks the difference increased to a mean of 43% (95% CI: 12% to 75%, P = .01) without significant differences in blood glucose values between the two groups. Individual responses after islet transplant varied and one monkey was weaned off insulin by 36 weeks. At terminal autopsy, organs appeared normal and there was no visible peritoneal reaction. No animal had polymerase chain reaction (PCR)-amplified signals of porcine endogenous retrovirus or exogenous virus infections in blood or tissues. CONCLUSION: Repeated intraperitoneal transplantation of microencapsulated neonatal porcine islets is a safe procedure in diabetic primates. It was shown to result in a significant reduction in insulin dose requirement in the majority of animals studied, whereas insulin requirement increased in controls.


Assuntos
Alginatos , Diabetes Mellitus Experimental/cirurgia , Transplante das Ilhotas Pancreáticas/métodos , Transplante Heterólogo/métodos , Animais , Animais Recém-Nascidos , Glicemia/metabolismo , Cápsulas , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/tratamento farmacológico , Modelos Animais de Doenças , Ácido Glucurônico , Ácidos Hexurônicos , Insulina/uso terapêutico , Macaca fascicularis , Masculino , Suínos
19.
Transplant Proc ; 37(6): 2715-8, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16182792

RESUMO

Short-term stimulation with insulinotropic factors may induce morphologic and functional changes in primary ductal cell cultures as a potential source of stem cells. We sought to assess the capacity of hepatocyte growth factor (HGF) to induce expression and maturation of proteins--PDX-1 and GLUT-2--and the subsequent beta-cell secretory profiles. HGF, which is involved in pancreatic development, may induce islet beta-cell neogenesis. Primary ductal cell monolayers were cultured in Click's + FBS 10% at 37 degrees C until tissue confluence. The medium was enriched with HGF (10 ng/mL for different periods); controls were treated for similar times with normal culture medium. At the end of the study, three-dimensional islet-like cell aggregates were observed in both conditions. In all conditions immunostaining studies showed positivity for the major endocrine-phenotype cell markers: insulin, PDX-1, glucokinase, and GLUT-2. Furthermore, treatment with HGF for short periods induced the expression of a functionally active, phosphorylated isoform of PDX-1. Finally, we observed that under basal conditions the cells initially and progressively released proinsulin throughout 5 days in all settings. Thereafter proinsulin was gradually replaced by insulin in the culture medium, reflecting a maturation progress. This pattern of insulin maturation and release was more evident when the cells were continuously stimulated with HGF for 12 days. The employed stimuli seemed to differentiate the original ductal cell layers toward endocrine cell phenotypes that synthesize and release proinsulin and subsequently insulin. HGF seems to provide a more efficient differentiation.


Assuntos
Ductos Pancreáticos/citologia , Animais , Animais Recém-Nascidos , Técnicas de Cultura de Células/métodos , Glucoquinase/metabolismo , Fator de Crescimento de Hepatócito/fisiologia , Proteínas de Homeodomínio/biossíntese , Imuno-Histoquímica , Insulina/biossíntese , Ductos Pancreáticos/fisiologia , Suínos , Transativadores/biossíntese
20.
Transplant Proc ; 37(1): 466-9, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15808678

RESUMO

Neonatal porcine islets within alginate microcapsules transplanted intraperitoneally (IP) or within semi-permeable macrocapsules (TheraCyte) and transplanted subcutaneously (SC) survive and reverse diabetes for up to 16 weeks in diabetic autoimmune nonobese diabetic (NOD) mice. The islets in microcapsules transplanted IP into nondiabetic cynomolgus monkeys survived for 8 weeks. Similar results were shown with islets transplanted in TheraCytes. Neither species showed adverse effects or evidence of infection with porcine endogenous retroviruses or other endemic pig viruses. Proof of principle is illustrated for successful xenotransplantation in humans.


Assuntos
Cápsulas , Transplante das Ilhotas Pancreáticas/fisiologia , Transplante Heterólogo/fisiologia , Animais , Diabetes Mellitus Tipo 1/cirurgia , Transplante das Ilhotas Pancreáticas/métodos , Transplante das Ilhotas Pancreáticas/patologia , Macaca fascicularis , Camundongos , Camundongos Endogâmicos NOD , Suínos , Transplante Heterólogo/patologia
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