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1.
Ann Surg Oncol ; 30(12): 7165-7171, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36367629

RESUMO

BACKGROUND: The 2009 American Thyroid Association (ATA) guidelines for medullary thyroid cancer (MTC) were created to unify national practice patterns. Our aims were to (1) evaluate national adherence to ATA guidelines before and after 2009, (2) identify factors that are associated with concordance with guidelines, and (3) evaluate whether there is an association between survival and concordant treatment. PATIENTS AND METHODS: Patients with MTC were identified from the 2009 to 2015 National Cancer Database. Adherence to ATA recommendations regarding extent of surgery (R61-R66) was analyzed. Logistic regression was used to determine predictors of discordance and propensity score matching was used to compare concordant treatment rates between time periods. Kaplan-Meier survival analysis was used to determine association between survival and concordant treatment. RESULTS: There were 3421 patients with MTC, and of these 3087 had M0 disease and 334 had M1 disease. We found that 72% of M0 cases adhered to R61-66, and 68% of M0 cases without advanced local disease were adherent to R61-63. Following propensity score matching, the adherence rate was 67% before 2009 and 74% after. Patient factors associated with discordant treatment were female gender, older age, treatment at a nonacademic facility, and living within 50 miles of the treatment facility. Adherence to guidelines was associated with improved overall survival (OS) (p < 0.01). CONCLUSIONS: Treatment of MTC was discordant from guidelines in 26% of cases from 2009 to 2015 compared with 33% prior to 2009 in a propensity matched analysis, and was most often in cases with localized, noninvasive disease. Improved adherence to guidelines may improve overall survival.


Assuntos
Carcinoma Neuroendócrino , Neoplasias da Glândula Tireoide , Humanos , Feminino , Estados Unidos , Masculino , Tireoidectomia , Neoplasias da Glândula Tireoide/cirurgia , Carcinoma Neuroendócrino/cirurgia , Estudos Retrospectivos
2.
World J Surg ; 47(2): 296-303, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36161354

RESUMO

BACKGROUND: The incidence of hyperparathyroidism has increased in the USA. The previous work from our institution detected environmental chemicals (EC) within hyperplastic parathyroid tumors. The National Health and Nutrition Examination Survey (NHANES) is a program designed to assess the health status of people in the USA and includes measurements of EC in serum. Our aim was to determine which EC are associated with elevated parathyroid hormone (PTH) and calcium levels within NHANES. METHODS: NHANES was queried from 2003-2016 for our analysis with calcium. A separate subgroup was queried from 2003-2006 that included PTH levels. Subjects with elevated calcium, and elevated PTH and normal Vitamin D levels were identified. Wilcoxon rank sum tests were used to analyze levels of EC in those with elevated calcium, and those with elevated PTH in the subgroup. All EC with p < 0.05 were then included in separate multivariate models adjusting for serum vitamin D and creatinine for PTH and albumin for calcium. RESULTS: There were 51,395 subjects analyzed, and calcium was elevated in 2.1% (1080) of subjects. Our subgroup analysis analyzed 14,681 subjects, and PTH was elevated without deficient Vitamin D in 9.4% (1,377). Twenty-nine different polychlorinated biphenyls and the organochlorine pesticides hexachlorobenzene, transnonachlor, oxychlordane, and p,p'-dichlorodiphenyldichloroethylene (DDE) were found to be associated with elevated calcium and separately with elevated PTH (all p < 0.05). CONCLUSION: In NHANES, 33 ECs were found to be associated with elevated calcium as well as elevated PTH levels on our subgroup analysis. These chemicals may lead us toward a causal link between environmental factors and the development of hyperparathyroidism and should be the focus of future studies looking at chemical levels within specimens.


Assuntos
Cálcio , Hiperparatireoidismo , Humanos , Inquéritos Nutricionais , Hiperparatireoidismo/induzido quimicamente , Hiperparatireoidismo/epidemiologia , Hormônio Paratireóideo , Vitamina D , Diclorodifenil Dicloroetileno
3.
Xenotransplantation ; 28(3): e12673, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33522023

RESUMO

BACKGROUND: Alginate-encapsulated islet xenografts have restored normoglycemia in diabetic animals for various periods of time. Plausible mechanisms of graft failure in vivo include immune rejection and hypoxia. We sought to understand the effects of encapsulated adult porcine islet (API) dosage on the peritoneal dissolved oxygen (DO) level in correlation to the achieved glycemic regulation in diabetic mice. METHODS: Adult porcine islets encapsulated in barium alginate were transplanted intraperitoneally in streptozotocin diabetic BALB/c mice at 6000 and 4000 islet equivalents (IEQ) and in normal mice at 500 IEQ; APIs encapsulated in calcium alginate were transplanted at 6000 IEQ in diabetic mice. In all cases, cell-free barium alginate capsules containing a perfluorocarbon emulsion were co-implanted for DO measurements using 19 F NMR spectroscopy. Blood glucose levels and peritoneal DO were measured over 60 days or until graft failure. Explanted capsules were evaluated microscopically and histologically. RESULTS: Both barium and calcium alginate-encapsulated APIs at 6000 IEQ reversed diabetes until day 60; barium alginate-encapsulated APIs at 4000 IEQ also reversed diabetes but with a higher failure rate. Transplanted APIs significantly reduced the peritoneal DO, approximately in a dose-dependent manner. The number of viable islets and the insulin content per capsule decreased over time. Capsules retrieved from normoglycemic mice exhibited minimal host cell adherence. CONCLUSIONS: Transplantation of encapsulated APIs can reduce peritoneal DO to severely hypoxic levels. Although normoglycemia could be maintained within the study period, the DO levels suggest that hypoxia is a factor contributing to loss of islet viability and insulin secretion with time in mice.


Assuntos
Diabetes Mellitus Experimental , Transplante das Ilhotas Pancreáticas , Ilhotas Pancreáticas , Alginatos , Animais , Sobrevivência de Enxerto , Camundongos , Camundongos Endogâmicos BALB C , Oxigênio , Estreptozocina , Suínos , Transplante Heterólogo
4.
Xenotransplantation ; 27(4): e12577, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31903659

RESUMO

BACKGROUND: Our goal was to identify clinically relevant immunotherapies that synergize with microencapsulation to protect adult porcine islet (API) xenografts in diabetic NOD mice. We have shown previously that dual costimulatory blockade (CTLA4-Ig plus anti-CD154 mAb) combined with encapsulation protects APIs long-term in NOD mice. Since no anti-CD154 mAbs currently are approved for use in humans, we tested the efficacy of other targeted immunosuppression regimens that might be used for diabetic patients receiving encapsulated islets. METHODS: Microencapsulated APIs were transplanted i.p. in diabetic NOD mice given either no immunosuppression or combinations immunosuppressive reagents. Graft function was monitored by blood glucose levels, i.p. glucose tolerance tests, and histology. Mechanisms of rejection were investigated by phenotyping host peritoneal cells and measuring graft site cytokine and chemokine levels. RESULTS: New immunosuppressive therapies were compared to CTLA4-Ig plus anti-CD154 mAb, used here as a control. The most effective was triple treatment with CTLA4-Ig, anti-CD154 mAb, and intracapsular CXCL12, and the next most effective was a non-depleting anti-CD4 mAb (YTS177.9) plus intracapsular CXCL12. Three additional regimens (CTLA4-Ig plus YTS177.9, YTS177.9 alone, and anti-OX40-Ligand mAb alone) significantly prolonged encapsulated API function. Dual treatment with CTLA4-Ig plus anti-CD40 mAb was as effective as CTLA4-Ig plus anti-CD154 mAb. Five other monotherapies and three combination therapies did not augment encapsulated API survival. Most peritoneal cytokines and chemokines were either absent or minimal. At necropsy, the capsules were intact, not fibrosed, and clean when function was maintained, but were coated with host cells if rejection had occurred. CONCLUSIONS: Multiple different immunotherapies which specifically inhibit CD4+ T cells, modulate T-cell trafficking, or interfere with antigen presentation can substitute for anti-CD154 mAb to prolong encapsulated islet xenograft function in diabetic NOD mice.


Assuntos
Diabetes Mellitus Experimental , Terapia de Imunossupressão/métodos , Transplante das Ilhotas Pancreáticas , Transplante Heterólogo , Animais , Ligante de CD40 , Diabetes Mellitus Experimental/cirurgia , Rejeição de Enxerto , Sobrevivência de Enxerto , Xenoenxertos , Camundongos , Camundongos Endogâmicos NOD , Suínos
6.
Xenotransplantation ; 25(6): e12450, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30117193

RESUMO

BACKGROUND: Xenogeneic donors would provide an unlimited source of islets for the treatment of type 1 diabetes (T1D). The goal of this study was to assess the function of microencapsulated adult porcine islets (APIs) transplanted ip in streptozotocin (STZ)-diabetic non-human primates (NHPs) given targeted immunosuppression. METHODS: APIs were encapsulated in: (a) single barium-gelled alginate capsules or (b) double alginate capsules with an inner, islet-containing compartment and a durable, biocompatible outer alginate layer. Immunosuppressed, streptozotocin-diabetic NHPs were transplanted ip with encapsulated APIs, and graft function was monitored by measuring blood glucose, %HbA1c, and porcine C-peptide. At graft failure, explanted capsules were assessed for biocompatibility and durability plus islet viability and functionality. Host immune responses were evaluated by phenotyping peritoneal cell populations, quantitation of peritoneal cytokines and chemokines, and measurement of anti-porcine IgG and IgM plus anti-Gal IgG. RESULTS: NHP recipients had reduced hyperglycemia, decreased exogenous insulin requirements, and lower percent hemoglobin A1c (%HbA1c) levels. Porcine C-peptide was detected in plasma of all recipients, but these levels diminished with time. However, relatively high levels of porcine C-peptide were detected locally in the peritoneal graft site of some recipients at sacrifice. IV glucose tolerance tests demonstrated metabolic function, but the grafts eventually failed in all diabetic NHPs regardless of the type of encapsulation or the host immunosuppression regimen. Explanted microcapsules were intact, "clean," and free-floating without evidence of fibrosis at graft failure, and some reversed diabetes when re-implanted ip in diabetic immunoincompetent mice. Histology of explanted capsules showed scant evidence of a host cellular response, and viable islets could be found. Flow cytometric analyses of peritoneal cells and peripheral blood showed similarly minimal evidence of a host immune response. Preformed anti-porcine IgG and IgM antibodies were present in recipient plasma, but these levels did not rise post-transplant. Peritoneal graft site cytokine or chemokine levels were equivalent to normal controls, with the exception of minimal elevation observed for IL-6 or IL-1ß, GRO-α, I-309, IP-10, and MCP-1. However, we found central necrosis in many of the encapsulated islets after graft failure, and explanted islets expressed endogenous markers of hypoxia (HIF-1α, osteopontin, and GLUT-1), suggesting a role for non-immunologic factors, likely hypoxia, in graft failure. CONCLUSIONS: With donor xenoislet microencapsulation and host immunosuppression, APIs corrected hyperglycemia after ip transplantation in STZ-diabetic NHPs in the short term. The islet xenografts lost efficacy gradually, but at graft failure, some viable islets remained, substantial porcine C-peptide was detected in the peritoneal graft site, and there was very little evidence of a host immune response. We postulate that chronic effects of non-immunologic factors, such as in vivo hypoxic and hyperglycemic conditions, damaged the encapsulated islet xenografts. To achieve long-term function, new approaches must be developed to prevent this damage, for example, by increasing the oxygen supply to microencapsulated islets in the ip space.


Assuntos
Diabetes Mellitus Experimental/induzido quimicamente , Composição de Medicamentos , Transplante das Ilhotas Pancreáticas , Ilhotas Pancreáticas/metabolismo , Transplante Heterólogo , Animais , Composição de Medicamentos/métodos , Rejeição de Enxerto/imunologia , Sobrevivência de Enxerto/imunologia , Xenoenxertos/imunologia , Terapia de Imunossupressão/métodos , Transplante das Ilhotas Pancreáticas/imunologia , Primatas , Estreptozocina/farmacologia , Suínos
7.
Xenotransplantation ; 24(1)2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-28247506

RESUMO

BACKGROUND: Adult porcine islets (APIs) constitute a promising alternative to human islets in treating type 1 diabetes. The intrahepatic site has been used in preclinical primate studies of API xenografts; however, an estimated two-thirds of donor islets are destroyed after intraportal infusion due to a number of factors, including the instant blood-mediated inflammatory reaction (IBMIR), immunosuppressant toxicity, and poor reestablishment of extracellular matrix connections. Intraperitoneal (ip) transplantation of non-vascularized encapsulated islets offers several advantages over intrahepatic transplantation of free islets, including avoidance of IBMIR, immunoprotection, accommodation of a larger graft volume, and reduced risk of hemorrhage. However, there exists evidence that the peritoneal site is hypoxic, which likely impedes islet function. METHODS: We tested the effect of hypoxia (2%-5% oxygen or pO2 : 15.2-38.0 mm Hg) on free and encapsulated APIs over a period of 6 days in culture. Free and encapsulated APIs under normoxia served as controls. Islet viability was evaluated with a viability/cytotoxicity assay using calcein AM and ethidium bromide on days 1, 3, and 6 of culture. Alamar blue assay was used to measure the metabolic activity on days 1 and 6. Insulin in spent medium was assayed by ELISA on days 1 and 6. RESULTS: Viability staining indicated that free islet clusters lost their integrity and underwent severe necrosis under hypoxia; encapsulated islets remained intact, even when they began to undergo necrosis. Under hypoxia, the metabolic activity and insulin secretion (normalized to metabolic activity) of both free and encapsulated islets decreased relative to islets cultured under normoxic conditions. CONCLUSIONS: Hypoxia (2%-5% oxygen or pO2 : 15.2-38.0 mm Hg) affects the viability, metabolic activity, and insulin secretion of both free and encapsulated APIs over a six-day culture period. Encapsulation augments islet integrity under hypoxia, but it does not prevent loss of viability, metabolic activity, or insulin secretion.


Assuntos
Hipóxia , Transplante das Ilhotas Pancreáticas , Ilhotas Pancreáticas/citologia , Animais , Diabetes Mellitus Experimental/terapia , Rejeição de Enxerto/prevenção & controle , Imunossupressores/farmacologia , Insulina/metabolismo , Secreção de Insulina , Transplante das Ilhotas Pancreáticas/métodos , Suínos , Transplante Heterólogo/métodos
8.
Semin Dial ; 30(4): 369-372, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28558417

RESUMO

Secondary hyperparathyroidism from chronic renal failure often requires a parathyroidectomy for correction. A successful parathyroidectomy often relies upon localization of all parathyroid tumors. Although most of the tumors are localized during a neck exploration, preoperative localization studies can help identify ectopic and supernumerary tumors. Three of the most common localization studies are radionuclide imaging, ultrasound, and CT scanning. Utility of these studies is strongly dependent on local institutional practice.


Assuntos
Hiperparatireoidismo Secundário/diagnóstico por imagem , Hiperparatireoidismo Secundário/etiologia , Falência Renal Crônica/complicações , Glândulas Paratireoides/diagnóstico por imagem , Humanos , Hiperparatireoidismo Secundário/cirurgia , Falência Renal Crônica/diagnóstico por imagem , Paratireoidectomia , Cintilografia , Tomografia Computadorizada por Raios X , Ultrassonografia
9.
Xenotransplantation ; 23(1): 46-52, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26916706

RESUMO

In 2009, the International Xenotransplantation Association (IXA) published a consensus document that provided guidelines and "recommendations" (not regulations) for those contemplating clinical trials of porcine islet transplantation. These guidelines included the IXA's opinion on what constituted "rigorous pre-clinical studies using the most relevant animal models" and were based on "non-human primate testing." We now report our discussion following a careful review of the 2009 guidelines as they relate to pre-clinical testing. In summary, we do not believe there is a need to greatly modify the conclusions and recommendations of the original consensus document. Pre-clinical studies should be sufficiently rigorous to provide optimism that a clinical trial is likely to be safe and has a realistic chance of success, but need not be so demanding that success might only be achieved by very prolonged experimentation, as this would not be in the interests of patients whose quality of life might benefit immensely from a successful islet xenotransplant. We believe these guidelines will be of benefit to both investigators planning a clinical trial and to institutions and regulatory authorities considering a proposal for a clinical trial. In addition, we suggest consideration should be given to establishing an IXA Clinical Trial Advisory Committee that would be available to advise (but not regulate) researchers considering initiating a clinical trial of xenotransplantation.


Assuntos
Ensaios Clínicos como Assunto , Diabetes Mellitus Tipo 1/cirurgia , Transplante das Ilhotas Pancreáticas , Transplante Heterólogo , Animais , Humanos , Consentimento Livre e Esclarecido , Transplante das Ilhotas Pancreáticas/métodos , Qualidade de Vida , Suínos , Transplante Heterólogo/métodos
10.
Xenotransplantation ; 21(2): 127-39, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24635017

RESUMO

BACKGROUND: Our goal was to improve islet transplantation as a therapy for patients with type I diabetes mellitus. Because human donor islets are scarce, we are studying islet xenografts in the diabetic NOD mouse model. We hypothesize that optimal xenoislet survival will be achieved by the combination of donor islet immunoisolation with recipient immunosuppression. We and others have studied adult and neonatal porcine islets as sources of tissue for microencapsulated islet xenografts, but we believe it is also advantageous to consider using islets from fish, which can be raised in large numbers relatively quickly and economically. Therefore, in this study, we have evaluated the function of microencapsulated xenogeneic piscine (tilapia) islets transplanted intraperitoneally (IP) in NOD mice in the presence of CD4(+) T-cell depletion and/or costimulatory blockade. METHODS: Spontaneously diabetic NOD mice or streptozotocin (STZ)-diabetic NOD-SCID mice were transplanted IP with microencapsulated tilapia islets. Recipient immunosuppression included anti-CD4 mAb, CTLA4-Ig, anti-CD80 mAb, anti-CD86 mAb, or anti-CD154 mAb, alone or in combination. Graft function was evaluated by blood glucose (BG) levels, intravenous (IV) and oral glucose tolerance tests (GTTs), histologic and immunohistochemical analyses of grafts, and flow cytometric analysis of peritoneal cells. RESULTS: Encapsulated tilapia islets normalized random BG levels for up to 210 days in NOD-SCID mice. In diabetic NOD mice, encapsulated tilapia islets were rejected on day 11 ± 4 with a peritoneal infiltrate of macrophages, eosinophils, B cells, occasional neutrophils, but few T cells. Immunohistochemical staining demonstrated the presence of murine IgG on tilapia islets within capsules of rejecting, non-immunosuppressed mice, as well as murine IgG-positive lymphocytes in the layer of host cells surrounding those capsules. These findings suggested that our barium (Ba)-gelled alginate capsules are permeable to IgG and that anti-piscine antibodies may be involved in the rejection of encapsulated tilapia islets in untreated mice. No single immunosuppressive agent prolonged encapsulated tilapia islet survival in NOD mice, but the combination of CTLA4-Ig plus anti-CD154 mAb extended tilapia islet graft survival until rejection at 119 ± 20 days and inhibited host cell recruitment to the peritoneal cavity. Triple treatment with CTLA4-Ig, anti-CD154 mAb, and anti-CD4 mAb allowed graft survival for 157 ± 35 days with little evidence of a host cellular reaction. IV and oral glucose tolerance tests (GTTs) of recipients with functioning xenografts demonstrated remarkably normal metabolic function. CONCLUSIONS: We conclude that microencapsulated tilapia islets can survive long term with excellent metabolic control in diabetic mice given targeted immunosuppression, suggesting that cross-species physiological incompatibility may not compromise the applicability of this novel approach for future clinical applications. We predict that an improved microcapsule that prevents the entrance of IgG will enhance tilapia islet survival in this model, possibly allowing the application of this technique with limited or no immunosuppression.


Assuntos
Diabetes Mellitus Experimental/cirurgia , Rejeição de Enxerto/imunologia , Sobrevivência de Enxerto/imunologia , Transplante das Ilhotas Pancreáticas , Ilhotas Pancreáticas/cirurgia , Transplante Heterólogo , Animais , Rejeição de Enxerto/prevenção & controle , Imunossupressores/uso terapêutico , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Suínos , Tilápia , Transplante Heterólogo/métodos
11.
World J Surg ; 38(6): 1268-73, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24744114

RESUMO

INTRODUCTION: Primary hyperparathyroidism (PHPT) results in increased bone turnover, resulting in bone mineral density (BMD) reduction and a predisposition towards fractures. Parathyroidectomy (PTX) is the only definitive cure. OBJECTIVE: The primary goals of this study were to investigate the impact of PTX on BMD in patients with PHPT and to identify factors associated with post-operative BMD improvement using a multivariate model. METHODS: Between 1999 and 2010, a total of 757 patients underwent PTX for treatment of PHPT; 123 patients had both a pre- and a post-operative dual-energy X-ray absorptiometry (DEXA) scan. A prospective database was queried to obtain information about patient demographics, medications, comorbidities, and pre- and post-operative laboratory values. A Cox regression model was used to stratify patients and to identify factors that independently predict BMD response following PTX in this patient population. RESULTS: Overall, mean percent change in BMD was +12.31 % at the spine, +8.9 % at the femoral neck (FN), and +8.5 % at the hip, with a mean follow-up of 2.3 ± 1.5 years. A total of 101 (82.1 %) patients had BMD improvement at their worst pre-operative site. In patients who improved, 69.9 % (n = 86) had >5 % increase. Factors associated with BMD improvement at the worst pre-operative site were as follows: male gender (hazard ratio [HR] 2.29; 95 % confidence interval [CI] 1.54-4.21); pre-operative BMD with T-score less than -2.0 (HR 1.89; 95 % CI 1.11-2.39); age <55 years (HR 1.74; 95 % CI 1.14-2.25); BMD DEXA scan at >2.5 years post-operatively (HR 1.71; 95 % CI 1.09-2.17); history of previous fracture (HR 1.24; 95 % CI 1.05-1.92); and private insurance (HR 1.18; 95 % CI 1.06-2.1). The use of bisphosphonates, estrogens, vitamin D supplementation, or tobacco; obesity; history of previous PTX, serum calcium or parathyroid hormone levels were not independently associated with post-operative BMD improvement. CONCLUSION: Osteoporosis is one of the established National Institutes of Health criteria for PTX in asymptomatic patients with PHPT, but BMD improvement is not consistently seen during the post-operative period. Gender, age, more severe pre-operative bone disease, and insurance status were all predictors for greater BMD improvement following PTX. Further studies with a rigorous post-operative BMD regimen are needed in order to validate these results.


Assuntos
Densidade Óssea/fisiologia , Hiperparatireoidismo Primário/cirurgia , Osteoporose/diagnóstico , Hormônio Paratireóideo/sangue , Paratireoidectomia/métodos , Absorciometria de Fóton , Adulto , Idoso , Estudos de Coortes , Intervalos de Confiança , Bases de Dados Factuais , Feminino , Seguimentos , Humanos , Hiperparatireoidismo Primário/diagnóstico , Masculino , Pessoa de Meia-Idade , Osteoporose/epidemiologia , Paratireoidectomia/efeitos adversos , Cuidados Pós-Operatórios/métodos , Valor Preditivo dos Testes , Cuidados Pré-Operatórios/métodos , Modelos de Riscos Proporcionais , Recuperação de Função Fisiológica , Estudos Retrospectivos , Medição de Risco , Índice de Gravidade de Doença , Resultado do Tratamento
12.
World J Surg ; 38(6): 1251-61, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24549997

RESUMO

BACKGROUND: Insulin-secreting beta-like cells are vulnerable to diabetic autoimmunity. We hypothesized that human thyroid neuroendocrine (NE) cells could be engineered to secrete human insulin, be glucose-responsive, and avoid autoimmunity. METHODS: Collagenase-digested thyroid tissue was cultured and subjected to size-based fluorescence-activated cell sorting. Insulin secretion and storage in NE cells transduced with viral vectors carrying an insulin sequence was assessed by enzyme-linked immunosorbent assay (ELISA) and immunogold transmission electron microscopy (TEM). Baseline mRNA expression was assessed by Illumina expression array analysis. Transduction with retrovirus expressing transcription factors PDX1, NGN3, MAFA, or HNF6 altered mRNA expression in a custom polymerase chain reaction (PCR) array. Gastrin-releasing peptide (GRP) in conditioned medium and cell lysates was determined by reverse transcription (RT)-PCR, ELISA, and immunohistochemistry. RESULTS: Isolation yielded an average of 2.2 × 10(6) cells/g thyroid tissue, which stained for calcitonin/calcitonin gene-related protein, expressed genes consistent with NE origins, and secreted GRP. Transduced cells secreted 56 % and retained 48 % of total insulin produced. Immunogold TEM revealed insulin in secretory vesicles. PDX1, NGN3, and MAFA overexpression increased expression of genes typical for hepatocytes and beta cells. Overexpression of HNF6 also increased the message of genes critical for glucose sensing. CONCLUSIONS: Human thyroid NE cells can produce human insulin, fractions of which are both secreted and retained in secretory granules. Overexpression of HNF6, PDX1, or NGN3 enhances expression of both hepatocyte and beta cell typical mRNAs, including the message of proteins critical for glucose sensing. These data suggest that reimplantation of engineered autologous NE cells may develop as a viable treatment for diabetes mellitus type 1.


Assuntos
Bioengenharia/métodos , Fator 6 Nuclear de Hepatócito/metabolismo , Insulina/farmacologia , Células Neuroendócrinas/metabolismo , Glândula Tireoide/citologia , Células Cultivadas , Diabetes Mellitus Tipo 1/tratamento farmacológico , Ensaio de Imunoadsorção Enzimática , Perfilação da Expressão Gênica , Fator 6 Nuclear de Hepatócito/genética , Humanos , Insulina/uso terapêutico , Células Secretoras de Insulina/metabolismo , Microscopia Eletrônica de Transmissão , Células Neuroendócrinas/citologia , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Sensibilidade e Especificidade , Glândula Tireoide/metabolismo
13.
Sci Total Environ ; 947: 174699, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-38997010

RESUMO

In the terrestrial environment, microplastics in specialty cropping systems have not been studied so far. Viticulture as a potential plastic-intensive management form and a land use with high erosion risks, plays an important role in transport and distribution of material to other terrestrial and aquatic systems. This paper is a first investigation of microplastics in vineyard soils, assessing the spatial distribution and composition of microplastics in organically and conventionally managed viticulture, and relates it to the macroplastic collected at the vineyards. Topsoils (0-10, 10-30 cm) and plastic particles on soil surfaces from eight vineyard lots were sampled. Four of the vineyards were under organic and four underconventional management and they were all located in the Moselle and Saar Wine Region (Rhineland-Palatinate, Germany). Microplastic analysis was performed via µFTIR chemical imaging after wet-chemical microplastic extraction from soil samples. The mean microplastic concentration was 4200 ± 2800 p kg-1 (mean ± SD), with detected mean sizes of 230 µm ± 300 µm. Most abundant polymers were PP (35.2 %), PA (25.3 %) and PE (15.5 %). The distribution pattern showed higher microplastic concentration in topsoil, at middle and bottom slope position. The smallest particle sizes were found in subsoil samples and bottom position. Thus, erosion is assumed to be a potential downhill transport pathway. According to our dataset, management seems to have no significant influence on microplastic abundance, but affects polymer composition. Polymer composition of micro- and macroplastics partly coincide, thus in-situ fragmentation, is considered the major input source. Based on our findings, we recommend further investigation of plastic pathways in speciality crop systems like viticulture.

14.
J Surg Res ; 185(1): 217-24, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23746767

RESUMO

BACKGROUND: Epidermal growth factor receptor (EGFR) overexpression (EGFR-H) is implicated in thyroid carcinoma disease progression; however, the clinicopathologic significance of EGFR-H in tumors that harbor EGFR and/or v-Raf murine sarcoma viral oncogene homolog B1 (BRAF)(V600E) mutations is unknown. METHODS: Tissue microarrays from 81 patients who had undergone thyroidectomy for carcinoma from 2002-2011 were scored for EGFR expression using immunohistochemistry. Somatic mutations in EGFR exons 19 and 21 and BRAF were analyzed. Correlations between the EGFR immunohistochemistry, EGFR, and BRAF(V600E) mutations and the clinicopathologic features were assessed. RESULTS: EGFR-H was detected in 39.5% of carcinomas (n = 32) from patients with papillary (PTC, 46.2%, n = 18), follicular (29.6%, n = 8), and anaplastic (100.0%, n = 6) but not medullary (0.0%, n = 9) thyroid carcinoma. BRAF(V600E) mutations were identified in 22.2% of the carcinoma cases (n = 18, 15 PTCs and 3 anaplastic thyroid carcinomas). No somatic EGFR mutations were detected in any subtype. On PTC univariate analysis, EGFR-H correlated with increasing stage, extrathyroid extension, tumor capsule invasion, adverse pathologic features (any demonstration of extrathyroid extension, tumor capsule invasion, lymphovascular invasion, lymph node metastasis, and/or distant metastasis), and BRAF(V600E) mutations. On multivariate analysis, EGFR-H correlated with BRAF(V600E) mutations. In BRAF wild-type PTCs, the correlation between EGFR-H and adverse pathologic features approached statistical significance (P = 0.065). CONCLUSIONS: EGFR-H could be an important biomarker for aggressive PTCs, particularly in BRAF wild-type PTCs. Despite EGFR-H in PTC, follicular thyroid carcinoma, and anaplastic thyroid carcinoma by immunohistochemistry, somatic EGFR mutations were absent. Therefore, future investigations of EGFR should consider histologic and immunohistochemical methods, in addition to molecular profiling of thyroid carcinomas. This multimodal approach is particularly important for future clinical trials testing anti-EGFR therapy.


Assuntos
Biomarcadores Tumorais/genética , Carcinoma Papilar/genética , Carcinoma Papilar/patologia , Carcinoma/genética , Carcinoma/patologia , Receptores ErbB/genética , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/metabolismo , Carcinoma/metabolismo , Carcinoma Papilar/metabolismo , Receptores ErbB/metabolismo , Éxons/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Prognóstico , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/metabolismo , Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide/metabolismo , Adulto Jovem
15.
Nat Med ; 12(3): 304-6, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16501570

RESUMO

We evaluated the ability of neonatal porcine islets to engraft and restore glucose control in pancreatectomized rhesus macaques. Although porcine islets transplanted into nonimmunosuppressed macaques were rapidly rejected by a process consistent with cellular rejection, recipients treated with a CD28-CD154 costimulation blockade regimen achieved sustained insulin independence (median survival, >140 days) without evidence of porcine endogenous retrovirus dissemination. Thus, neonatal porcine islets represent a promising solution to the crucial supply problem in clinical islet transplantation.


Assuntos
Sobrevivência de Enxerto/imunologia , Transplante das Ilhotas Pancreáticas/imunologia , Macaca/imunologia , Suínos , Animais , Animais Recém-Nascidos , Terapia Baseada em Transplante de Células e Tecidos , Rejeição de Enxerto/imunologia , Ilhotas Pancreáticas/citologia , Ilhotas Pancreáticas/imunologia , Pancreatectomia , Suínos/imunologia , Fatores de Tempo , Transplante Heterólogo/imunologia
16.
Sci Rep ; 12(1): 6401, 2022 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-35430621

RESUMO

Plastic contamination of terrestrial ecosystems and arable soils pose potentially negative impacts on several soil functions. Whereas substantial plastic contamination is now traceable in agro-landscapes, often internal-caused by the application of fertilizers such as sewage sludge, questions remain unanswered concerning what happens to the plastic after incorporation. Based on a combined surface and depth sampling approach, including density separation, fluorescence staining and ATR-FTIR or µFTIR analyses, we quantified macro- and microplastic abundance on two agricultural fields-34 years after the last sewage sludge application. By sub-dividing the study area around sludge application sites, we were able to determine spatial distribution and spreading of plastics. Past sewage sludge application led to a still high density of macroplastics (637.12 items per hectare) on agricultural soil surfaces. Microplastic concentration, measured down to 90 cm depth, ranged from 0.00 to 56.18 particles per kg of dry soil weight. Maximum microplastic concentrations were found in regularly ploughed topsoils. After 34 years without sewage sludge application, macro- and microplastic loads were significantly higher on former application areas, compared to surrounding areas without history of direct sewage application. We found that anthropogenic ploughing was mainly responsible for plastic spread, as opposed to natural transport processes like erosion. Furthermore, small-scale lateral to vertical heterogeneous distribution of macro- and microplastics highlights the need to determine appropriate sampling strategies and the modelling of macro- and microplastic transport in soils.


Assuntos
Microplásticos , Esgotos , Ecossistema , Monitoramento Ambiental , Plásticos , Solo
17.
Prosthet Orthot Int ; 46(4): e335-e340, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35344529

RESUMO

BACKGROUND: Making a prosthesis for an individual with limb loss is a highly personalized process. A currently unexplored area is whether there are tangible benefits in greater patient engagement during the cosmetic designing of their prostheses. We examined the current clinical practice of engaging patients in prosthetic cosmetic designing and identified factors associated with patient outcomes. METHODS: One hundred and four prosthetists and 28 prosthesis users were surveyed in this cross-sectional study. The questionnaires covered aspects of prosthetic prescription and fabrication, users' perceived level of engagement, and self-reported outcomes. Regression analyses were used to examine the associations between patients' perceived levels of engagement during the design process, satisfaction, and other outcomes. RESULTS: Seventy-five percent of the prosthesis users reported being offered at least one cosmetic option during the making of their prostheses, which corroborated with 82.7% of the prosthetists reporting that they typically engage their patients in this aspect of their practices. Patients who were offered at least one cosmetic design option reported significantly greater satisfaction ( P = 0.027) than those who were not offered such an option. Patients' level of satisfaction regarding the look of their prostheses was significantly correlated with their perception that their prostheses empower them in daily activities (r = 0.415, P = 0.028). CONCLUSION: Engaging patients in the cosmetic designing of their prostheses is a widely accepted practice. Patients who are more satisfied with the look of their prostheses perceived higher levels of empowerment. Prosthetic practitioners should consider the potential outcome benefits of higher level engagement for users of prosthetic devices.


Assuntos
Amputados , Membros Artificiais , Estudos Transversais , Humanos , Participação do Paciente , Satisfação do Paciente
18.
Front Bioeng Biotechnol ; 10: 886483, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35651551

RESUMO

Pancreatic islet transplantation improves metabolic control and prevents complications in patients with brittle type 1 diabetes (T1D). However, chronic immunosuppression is required to prevent allograft rejection and recurrence of autoimmunity. Islet encapsulation may eliminate the need for immunosuppression. Here, we analyzed in parallel two microencapsulation platforms that provided long-term diabetes reversal in preclinical T1D models, alginate single and double capsules versus polyethylene glycol conformal coating, to identify benefits and weaknesses that could inform the design of future clinical trials with microencapsulated islets. We performed in vitro and in vivo functionality assays with human islets and analyzed the explanted grafts by immunofluorescence. We quantified the size of islets and capsules, measured capsule permeability, and used these data for in silico simulations of islet functionality in COMSOL Multiphysics. We demonstrated that insulin response to glucose stimulation is dependent on capsule size, and the presence of permselective materials augments delays in insulin secretion. Non-coated and conformally coated islets could be transplanted into the fat pad of diabetic mice, resulting in comparable functionality and metabolic control. Mac-2+ cells were found in conformally coated grafts, indicating possible host reactivity. Due to their larger volume, alginate capsules were transplanted in the peritoneal cavity. Despite achieving diabetes reversal, changes in islet composition were found in retrieved capsules, and recipient mice experienced hypoglycemia indicative of hyperinsulinemia induced by glucose retention in large capsules as the in silico model predicted. We concluded that minimal capsule size is critical for physiological insulin secretion, and anti-inflammatory modulation may be beneficial for small conformal capsules.

19.
Sci Total Environ ; 796: 149037, 2021 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-34280631

RESUMO

Phosphorus (P) loss from soil may trigger freshwater eutrophication and endanger supply with drinking water regionally. The present paper aims at encouraging discussion and development of sophisticated strategies for risk assessment of P loss from soils of riparian buffer zones (RBZ) as a prerequisite for targeted and effective mitigation of such P losses and their effects on freshwater eutrophication. We use data from a case study on RBZ soils in Germany to compare the performance of different environmental indicators of a risk for P loss from soil. Our data suggest that RBZ soils are temporarily sinks or sources for P. The spatial hotspots of P loss are the topsoils and the deep P stocks (labile P enriched in RBZ subsoils below on average 87.5 cm depth). We discuss four aspects to be considered conceptually and methodologically in the assessment of a risk for P loss from RBZ soils: (1) spatial heterogeneity and spatial bias; (2) temporal heterogeneity and temporal bias; (3) conceptual bias caused by different dynamics of individual P fractions; and (4) adequacy of threshold values. To minimize bias, we propose to assess risk for P loss from RBZ soils using a geospatial, temporally resolved sampling strategy, site-specific or regional threshold values, and a P fractionation approach. For this purpose, we introduce PdHCl as a risk indicator, which is not susceptible to very short-term dynamics (in contrast to water-soluble P).


Assuntos
Fósforo , Solo , Eutrofização , Água Doce , Medição de Risco
20.
Sci Total Environ ; 784: 147131, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-33895510

RESUMO

Subsurface phosphorus (P) translocation along slopes may contribute to P enrichment in the subsoils of riparian buffer zones. Such "deep P stocks" might contribute to P concentrations and eutrophication of freshwaters. Better understanding of subsurface P translocation through the soilscape is required to understand the build-up of deep P stocks and to develop targeted mitigation strategies against it. However, such soilscape P dynamics are difficult to tackle due to logistical limitations of common field sampling strategies. Here, we introduce the Soilscape Network Approach (SNAp) as a solution to this problem: It enables to study soilscape P dynamics from a new analytical perspective but on the basis of common field sampling strategies. For this purpose, we are using the graph visualization platform Gephi with field data from a study on subsurface P translocation in Germany. The application of SNAp corroborated prior results regarding deep P stocks in riparian buffer zones, and it enabled the identification of major P sink and source sites as well as dominant P translocation pathways. Our SNAp analysis suggests that subsurface P translocation from topslopes and middle slopes is relevant for the build-up of deep P stocks in the studied toeslope subsoils, especially with shallow basalt or agricultural fertilizer inputs on the top- and middle slopes. Besides, the data imply that lateral P translocation along the studied slopes is small on short slopes, increases until a maximum is achieved, then decreases again when slopes are too long. The SNAp analysis offers new findings which gave valuable insights for the mitigation of subsurface P translocation along slopes.

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