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1.
Ann Surg Oncol ; 30(12): 7165-7171, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36367629

RESUMEN

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.


Asunto(s)
Carcinoma Neuroendocrino , Neoplasias de la Tiroides , Humanos , Femenino , Estados Unidos , Masculino , Tiroidectomía , Neoplasias de la Tiroides/cirugía , Carcinoma Neuroendocrino/cirugía , Estudios Retrospectivos
2.
World J Surg ; 47(2): 296-303, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36161354

RESUMEN

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.


Asunto(s)
Calcio , Hiperparatiroidismo , Humanos , Encuestas Nutricionales , Hiperparatiroidismo/inducido químicamente , Hiperparatiroidismo/epidemiología , Hormona Paratiroidea , Vitamina D , Diclorodifenil Dicloroetileno
3.
Xenotransplantation ; 28(3): e12673, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33522023

RESUMEN

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.


Asunto(s)
Diabetes Mellitus Experimental , Trasplante de Islotes Pancreáticos , Islotes Pancreáticos , Alginatos , Animales , Supervivencia de Injerto , Ratones , Ratones Endogámicos BALB C , Oxígeno , Estreptozocina , Porcinos , Trasplante Heterólogo
4.
Xenotransplantation ; 27(4): e12577, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-31903659

RESUMEN

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.


Asunto(s)
Diabetes Mellitus Experimental , Terapia de Inmunosupresión/métodos , Trasplante de Islotes Pancreáticos , Trasplante Heterólogo , Animales , Ligando de CD40 , Diabetes Mellitus Experimental/cirugía , Rechazo de Injerto , Supervivencia de Injerto , Xenoinjertos , Ratones , Ratones Endogámicos NOD , Porcinos
6.
Xenotransplantation ; 25(6): e12450, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30117193

RESUMEN

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.


Asunto(s)
Diabetes Mellitus Experimental/inducido químicamente , Composición de Medicamentos , Trasplante de Islotes Pancreáticos , Islotes Pancreáticos/metabolismo , Trasplante Heterólogo , Animales , Composición de Medicamentos/métodos , Rechazo de Injerto/inmunología , Supervivencia de Injerto/inmunología , Xenoinjertos/inmunología , Terapia de Inmunosupresión/métodos , Trasplante de Islotes Pancreáticos/inmunología , Primates , Estreptozocina/farmacología , Porcinos
7.
Semin Dial ; 30(4): 369-372, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28558417

RESUMEN

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.


Asunto(s)
Hiperparatiroidismo Secundario/diagnóstico por imagen , Hiperparatiroidismo Secundario/etiología , Fallo Renal Crónico/complicaciones , Glándulas Paratiroides/diagnóstico por imagen , Humanos , Hiperparatiroidismo Secundario/cirugía , Fallo Renal Crónico/diagnóstico por imagen , Paratiroidectomía , Cintigrafía , Tomografía Computarizada por Rayos X , Ultrasonografía
8.
Xenotransplantation ; 21(2): 127-39, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24635017

RESUMEN

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.


Asunto(s)
Diabetes Mellitus Experimental/cirugía , Rechazo de Injerto/inmunología , Supervivencia de Injerto/inmunología , Trasplante de Islotes Pancreáticos , Islotes Pancreáticos/cirugía , Trasplante Heterólogo , Animales , Rechazo de Injerto/prevención & control , Inmunosupresores/uso terapéutico , Ratones , Ratones Endogámicos NOD , Ratones SCID , Porcinos , Tilapia , Trasplante Heterólogo/métodos
9.
World J Surg ; 38(6): 1251-61, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24549997

RESUMEN

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.


Asunto(s)
Bioingeniería/métodos , Factor Nuclear 6 del Hepatocito/metabolismo , Insulina/farmacología , Células Neuroendocrinas/metabolismo , Glándula Tiroides/citología , Células Cultivadas , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Ensayo de Inmunoadsorción Enzimática , Perfilación de la Expresión Génica , Factor Nuclear 6 del Hepatocito/genética , Humanos , Insulina/uso terapéutico , Células Secretoras de Insulina/metabolismo , Microscopía Electrónica de Transmisión , Células Neuroendocrinas/citología , ARN Mensajero/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa , Sensibilidad y Especificidad , Glándula Tiroides/metabolismo
10.
Sci Total Environ ; 947: 174699, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-38997010

RESUMEN

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.

11.
J Surg Res ; 185(1): 217-24, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23746767

RESUMEN

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.


Asunto(s)
Biomarcadores de Tumor/genética , Carcinoma Papilar/genética , Carcinoma Papilar/patología , Carcinoma/genética , Carcinoma/patología , Receptores ErbB/genética , Neoplasias de la Tiroides/genética , Neoplasias de la Tiroides/patología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/metabolismo , Carcinoma/metabolismo , Carcinoma Papilar/metabolismo , Receptores ErbB/metabolismo , Exones/genética , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Pronóstico , Proteínas Proto-Oncogénicas B-raf/genética , Proteínas Proto-Oncogénicas B-raf/metabolismo , Cáncer Papilar Tiroideo , Neoplasias de la Tiroides/metabolismo , Adulto Joven
12.
Nat Med ; 12(3): 304-6, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16501570

RESUMEN

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.


Asunto(s)
Supervivencia de Injerto/inmunología , Trasplante de Islotes Pancreáticos/inmunología , Macaca/inmunología , Porcinos , Animales , Animales Recién Nacidos , Tratamiento Basado en Trasplante de Células y Tejidos , Rechazo de Injerto/inmunología , Islotes Pancreáticos/citología , Islotes Pancreáticos/inmunología , Pancreatectomía , Porcinos/inmunología , Factores de Tiempo , Trasplante Heterólogo/inmunología
13.
Sci Rep ; 12(1): 6401, 2022 04 16.
Artículo en Inglés | MEDLINE | ID: mdl-35430621

RESUMEN

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.


Asunto(s)
Microplásticos , Aguas del Alcantarillado , Ecosistema , Monitoreo del Ambiente , Plásticos , Suelo
14.
Front Bioeng Biotechnol ; 10: 886483, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35651551

RESUMEN

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.

15.
Sci Total Environ ; 796: 149037, 2021 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-34280631

RESUMEN

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).


Asunto(s)
Fósforo , Suelo , Eutrofización , Agua Dulce , Medición de Riesgo
16.
Surgery ; 169(1): 102-108, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32771296

RESUMEN

BACKGROUND: The incidence of primary hyperparathyroidism has increased 300% in the United States in the past 30 years, and secondary hyperparathyroidism is almost universal in patients with end-stage renal disease. We assessed the presence of environmental chemicals in human hyperplastic parathyroid tumors as possible contributing factors to this increase. METHODS: Cryopreserved hyperplastic parathyroid tumors and normal human parathyroids were analyzed by gas chromatography and liquid chromatography coupled to ultra-high-resolution mass spectrometry, bioinformatics, and biostatistics. RESULTS: Detected environmental chemicals included polychlorinated biphenyls, polybrominated diphenyl ethers, dichloro-diphenyl-trichloroethane derivatives, and other insecticides. A total of 99% had p,p'-dichlorodiphenyldichloroethylene. More than 50% contained other environmental chemicals, and many classified as endocrine disruptors. Polychlorinated biphenyl-28 and polychlorinated biphenyl-49 levels correlated positively with parathyroid tumor mass. Polybrominated diphenyl ether-47 concentrations in tumors were inversely correlated with patients' serum calcium levels. Cellular metabolites in pathways of purine and pyrimidine synthesis and mitochondrial energy production were associated with tumor growth and with p,p'-dichlorodiphenyldichloroethylene in primary hyperparathyroidism tumors. In normal parathyroids, p,p'-dichlorodiphenyldichloroethylene , polychlorinated biphenyl-28, polychlorinated biphenyl-74, and polychlorinated biphenyl-153, but not p,p'-dichlorodiphenyldichloroethylene or polychlorinated biphenyl-49, were detected. CONCLUSION: Environmental chemicals are present in human parathyroid tumors and warrant detailed epidemiologic and mechanistic studies to test for causal links to the growth of human parathyroid tumors.


Asunto(s)
Disruptores Endocrinos/análisis , Contaminantes Ambientales/análisis , Hiperparatiroidismo Primario/epidemiología , Hiperparatiroidismo Secundario/epidemiología , Glándulas Paratiroides/química , Neoplasias de las Paratiroides/epidemiología , Causalidad , Disruptores Endocrinos/efectos adversos , Contaminantes Ambientales/efectos adversos , Femenino , Cromatografía de Gases y Espectrometría de Masas , Éteres Difenilos Halogenados/efectos adversos , Éteres Difenilos Halogenados/análisis , Humanos , Hiperparatiroidismo Primario/patología , Hiperparatiroidismo Primario/cirugía , Hiperparatiroidismo Secundario/etiología , Hiperparatiroidismo Secundario/patología , Hiperparatiroidismo Secundario/cirugía , Incidencia , Masculino , Persona de Mediana Edad , Glándulas Paratiroides/patología , Glándulas Paratiroides/cirugía , Neoplasias de las Paratiroides/complicaciones , Neoplasias de las Paratiroides/patología , Neoplasias de las Paratiroides/cirugía , Paratiroidectomía , Bifenilos Policlorados/efectos adversos , Bifenilos Policlorados/análisis , Estudios Retrospectivos , Estados Unidos/epidemiología
17.
Surgery ; 169(1): 114-119, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32718801

RESUMEN

BACKGROUND: The impact of parathyroidectomy on neuropsychiatric symptoms in primary hyperparathyroidism remains poorly defined. The validated scales Patient Health Questionnaire-9 and Generalized Anxiety Disorder-7 can be used to assess depression and anxiety, respectively. Our aim was to prospectively characterize the changes in neuropsychiatric symptoms after parathyroidectomy. METHODS: Patients undergoing parathyroidectomy and thyroidectomy (control) from two institutions between 2014 and 2019 were prospectively administered a questionnaire assessing neuropsychiatric symptoms before and after surgery. Paired t tests compared preoperative with postoperative neuropsychiatric symptoms and t tests compared differences in neuropsychiatric symptoms between parathyroidectomy and thyroidectomy. RESULTS: A total of 244 patients underwent parathyroidectomy and 161 underwent thyroidectomy. We observed improvement in neuropsychiatric symptoms after parathyroidectomy (6.2 [5.0-7.4], P < .01). Preoperatively, neuropsychiatric symptoms were more prevalent in patients undergoing parathyroidectomy when compared with thyroidectomy (11.2 ± 11.5 vs 7.5 ± 8.2, P < .01); however, after surgery there was no difference between the two groups (5.1 ± 7.1 vs 5.4 ± 7.2, P = .59). Preoperatively, 27.5% and 18.0% of patients endorsed moderate to severe depression and anxiety, which fell to 8.2% and 5.3%, respectively, (P < .01) after surgery. CONCLUSION: Patients undergoing parathyroidectomy showed significant improvement in neuropsychiatric symptoms after surgery. Neuropsychiatric symptoms are more prevalent in patients with primary hyperparathyroidism. Neuropsychiatric symptoms should be assessed in all patients with primary hyperparathyroidism and should be considered a relative indication for parathyroidectomy.


Asunto(s)
Ansiedad/epidemiología , Depresión/epidemiología , Hiperparatiroidismo Primario/cirugía , Paratiroidectomía , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Ansiedad/diagnóstico , Ansiedad/etiología , Ansiedad/psicología , Estudios de Casos y Controles , Depresión/diagnóstico , Depresión/etiología , Depresión/psicología , Femenino , Humanos , Hiperparatiroidismo Primario/complicaciones , Hiperparatiroidismo Primario/psicología , Masculino , Persona de Mediana Edad , Cuestionario de Salud del Paciente/estadística & datos numéricos , Periodo Posoperatorio , Periodo Preoperatorio , Prevalencia , Estudios Prospectivos , Índice de Severidad de la Enfermedad , Enfermedades de la Tiroides/complicaciones , Enfermedades de la Tiroides/psicología , Enfermedades de la Tiroides/cirugía , Tiroidectomía , Resultado del Tratamiento , Adulto Joven
18.
Transplantation ; 104(2): 259-269, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31385927

RESUMEN

BACKGROUND: We have utilized a noninvasive technique for measuring the partial pressure of oxygen (pO2) in alginate microcapsules implanted intraperitoneally in healthy nonhuman primates (NHPs). Average pO2 is important for determining if a transplant site and capsules with certain passive diffusion characteristics can support the islet viability, metabolic activity, and dose necessary to reverse diabetes. METHODS: Perfluoro-15-crown-5-ether alginate capsules were infused intraperitoneally into 3 healthy NHPs. Peritoneal pO2 levels were measured on days 0 and 7 using fluorine-19 magnetic resonance relaxometry and a fiber-optic probe. Fluorine-19 MRI was used to determine the locations of capsules within the peritoneal space on days 0 and 7. Gross and histologic evaluations of the capsules were used to assess their biocompatibility postmortem. RESULTS: At day 0 immediately after infusion of capsules equilibrated to room air, capsules were concentrated near the infusion site, and the pO2 measurement using magnetic resonance relaxometry was 147 ± 9 mm Hg. On day 7 after capsules were dispersed throughout the peritoneal cavity, the pO2 level was 61 ± 11 mm Hg. Measurements using the fiber-optic oxygen sensor were 132 ± 7.5 mm Hg (day 0) and 89 ± 6.1 mm Hg (day 7). Perfluoro-15-crown-5-ether capsules retrieved on day 7 were intact and free-floating without host cell attachment, although the numbers of peritoneal CD20 B cells, CD4 and CD8 T cells, and CD14 macrophages increased consistent with a mild foreign body reaction. CONCLUSIONS: The peritoneal pO2 of normal NHPs is relatively low and we predict would decrease further when encapsulated islets are transplanted intraperitoneally.


Asunto(s)
Alginatos/farmacología , Diabetes Mellitus Experimental/cirugía , Imagen por Resonancia Magnética con Fluor-19/métodos , Trasplante de Islotes Pancreáticos/métodos , Consumo de Oxígeno/fisiología , Oxígeno/metabolismo , Cavidad Peritoneal/cirugía , Animales , Cápsulas , Diabetes Mellitus Experimental/metabolismo , Femenino , Supervivencia de Injerto , Macaca mulatta , Presión Parcial
19.
Am Surg ; 75(7): 579-82; discussion 582-3, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19655601

RESUMEN

Isolated familial hyperparathyroidism (FHPT) not associated with multiple endocrine neoplasia is a rare and aggressive form of primary hyperparathyroidism. The traditional management of FHPT is a bilateral neck exploration with an increased rate of multigland hyperplasia, supernumerary glands, and recurrence. A prospective database was queried, which included 1383 consecutive parathyroidectomies between 1992 and 2008, and 28 patients with FHPT were identified. Patient demographics, pathology, intraoperative parathyroid hormone (IOPTH) kinetics, recurrence patterns, and accuracy of localization studies were analyzed. Twenty-one patients underwent bilateral neck explorations as an initial surgery, and seven patients had nine unilateral neck explorations for recurrent hyperparathyroidism. Overall cure rate was 89.2 per cent with a mean follow-up of 2.9 years (range: 6 months to 9.2 years); 64.3 per cent of patients had multigland disease. IOPTH helped identify supernumerary glands in three (12.5%) patients and accurately lateralized recurrent disease in eight of nine surgeries (88.8%). Tc-99m-Sestamibi failed to identify multigland disease in 11 patients (52.3%). FHPT has a greater prevalence of multigland disease, decreased utility of sestamibi scanning, and a higher recurrence rate than sporadic primary hyperparathyroidism. In FHPT, IOPTH is a useful adjunct in identifying additional tumors and in select cases may play a role in tumor localization.


Asunto(s)
Hiperparatiroidismo Primario/diagnóstico , Hiperparatiroidismo Primario/cirugía , Paratiroidectomía , Adolescente , Adulto , Anciano , Estudios de Cohortes , Femenino , Humanos , Hiperparatiroidismo Primario/genética , Masculino , Persona de Mediana Edad , Monitoreo Intraoperatorio , Hormona Paratiroidea/sangre , Valor Predictivo de las Pruebas , Radiofármacos , Recurrencia , Estudios Retrospectivos , Tecnecio Tc 99m Sestamibi , Resultado del Tratamiento , Adulto Joven
20.
Am Surg ; 85(9): 939-943, 2019 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-31638503

RESUMEN

Reoperative parathyroid surgery (REOPS) is often associated with lower cure rates and greater risk of nerve injury and hypoparathyroidism. The aim of this study was to evaluate cure rates, pathology, complications, and the efficacy of preoperative localization in patients requiring REOPS. Between 1992 and 2017, 2491 consecutive patients underwent parathyroidectomy for primary hyperparathyroidism. With Institutional Review Board approval, our prospectively collected parathyroidectomy outcomes database was queried for operative findings, outcomes, pathology, and localization methodology. Three hundred forty-six patients had REOPS (111 men/32% and 235 women/68%), with an overall cure rate of 91 per cent and a mean follow-up of 1.9 ± 0.7 years. The average preoperative serum calcium and parathyroid hormone were 11 ± 1 mg/dL and 373 ± 796 pg/mL, respectively. Normalization of intraoperative parathyroid hormone occurred in 248 patients and it was predictive of cure in 98.8 per cent of patients. A single adenoma was resected in 253 patients (75%), and the superior gland location was most common at 57 per cent. Ectopic glands were identified in only 33 patients. When preoperative imaging localized a lesion, a tumor was identified in that location in 75.4 per cent of sestamibi or SPECT/CT scans, 57.8 per cent of CT, 61.2 per cent of MRI, and 46.2 per cent of US. When at least two imaging modalities were concordant, sensitivity improved to 91.6 per cent (P < 0.001). Complication rates of permanent hypoparathyroidism and recurrent nerve palsy occurred in 0.03 per cent of patients. REOP for recurrent or persistent primary hyperparathyroidism has a cure rate of 91 per cent. Most missed parathyroid tumors are in the neck, and multimodal imaging improves preoperative localization and success.


Asunto(s)
Adenoma/cirugía , Hiperparatiroidismo Primario/cirugía , Neoplasias de las Paratiroides/cirugía , Paratiroidectomía/métodos , Reoperación , Adenoma/sangre , Adenoma/diagnóstico por imagen , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Calcio/sangre , Femenino , Estudios de Seguimiento , Humanos , Hiperparatiroidismo Primario/sangre , Hiperparatiroidismo Primario/diagnóstico por imagen , Hipoparatiroidismo , Masculino , Persona de Mediana Edad , Parálisis , Hormona Paratiroidea/sangre , Neoplasias de las Paratiroides/sangre , Neoplasias de las Paratiroides/diagnóstico por imagen , Paratiroidectomía/efectos adversos , Complicaciones Posoperatorias , Tomografía Computarizada por Tomografía Computarizada de Emisión de Fotón Único , Tecnecio Tc 99m Sestamibi , Adulto Joven
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