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1.
Molecules ; 24(19)2019 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-31569578

RESUMEN

In this study, Carum carvi L. essential oil (CEO) and Origanum majorana L. essential oil (MEO) was steam-distillated under reduced pressure. We henceforth obtained three fractions for each essential oil: CF1, CF2, CF3, MF1, MF2, and MF3. Then, these fractions were characterized using the gas chromatography-mass spectrometry (GC-MS) technique. The results indicated that some fractions were rich in oxygenated compounds (i.e., CF2, CF3, MF2, and MF3) with concentrations ranging from 79.21% to 98.56%. Therefore, the influence of the chemical composition of the essential oils on their antifungal activity was studied. For this purpose, three food spoilage fungi were isolated, identified, and inoculated in vitro, in order to measure the antifungal activity of CEO, MEO, and their fractions. The results showed that stronger fungi growth inhibitions (FGI) (above 95%) were found in fractions with higher percentages of oxygenated compounds, especially with (-)-carvone and terpin-4-ol as the major components. Firstly, this work reveals that the free-terpenes hydrocarbons fractions obtained from MEO present higher antifungal activity than the raw essential oil against two families of fungi. Then, it suggests that the isolation of (-)-carvone (97.15 ± 5.97%) from CEO via vacuum distillation can be employed successfully to improve antifungal activity by killing fungi (FGI = 100%). This study highlights that separation under reduced pressure is a simple green method to obtain fractions or to isolate compounds with higher biological activity useful for pharmaceutical products or natural additives in formulations.


Asunto(s)
Hidrocarburos/química , Aceites Volátiles/química , Aceites Volátiles/farmacología , Terpenos/química , Antifúngicos , Pruebas de Sensibilidad Microbiana , Aceites Volátiles/aislamiento & purificación
2.
Rev Med Chil ; 147(7): 852-859, 2019 Jul.
Artículo en Español | MEDLINE | ID: mdl-31859983

RESUMEN

BACKGROUND: Classification of growth hormone (GH) - secreting tumors by the granular pattern might predict their clinical behavior in acromegalic patients. There are several other prognostic factors. AIM: To compare the features at presentation and cure rates of patients with GH secreting tumors according to the granular pattern, and to define independent prognostic factors for surgical treatment in these patients. MATERIAL AND METHODS: A retrospective, observational study of 85 active acromegalic patients surgically treated in two medical centers. RESULTS: Seventy-four patients (87%) were classified as having densely granulated (DG) and 11 (13%) as sparsely granulated (SG) tumors. The latter were less active biochemically, had a higher rate of macroadenoma and cavernous sinus invasion and had a lower rate of biochemical cure than the DG group. Several characteristics were associated with disease persistence but only age (Odds ratio (OR) = 0.93) and cavernous sinus invasion (OR = 21.7) were independently associated in the logistic regression model. CONCLUSIONS: The sparsely granulated pattern is associated with a more aggressive behavior, but the main determinants of prognosis are age and cavernous sinus invasion.


Asunto(s)
Adenoma Hipofisario Secretor de Hormona del Crecimiento/patología , Adulto , Femenino , Adenoma Hipofisario Secretor de Hormona del Crecimiento/diagnóstico por imagen , Humanos , Inmunohistoquímica , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos
3.
Rev Med Chil ; 145(8): 1028-1037, 2017 Aug.
Artículo en Español | MEDLINE | ID: mdl-29189861

RESUMEN

The thyroid nodule is a frequent cause of primary care consultation. The prevalence of a palpable thyroid nodule is approximately 4-7%, increasing up to 67% by the incidental detection of nodules on ultrasound. The vast majority are benign and asymptomatic, staying stable over time. The clinical importance of studying a thyroid nodule is to exclude thyroid cancer, which occurs in 5 to 10% of the nodules. The Board of SOCHED (Chilean Society of Endocrinology and Diabetes) asked the Thyroid Study Group to develop a consensus regarding the diagnostic management of the thyroid nodule in Chile, aimed at non-specialist physicians and adapted to the national reality. To this end, a multidisciplinary group of 31 experts was established among university academics, active researchers with publications on the subject and prominent members of scientific societies of endocrinology, head and neck surgery, pathology and radiology. A total of 14 questions were developed with key aspects for the diagnosis and subsequent referral of patients with thyroid nodules, which were addressed by the participants. In those areas where the evidence was insufficient or the national reality had to be considered, the consensus opinion of the experts was used through the Delphi methodology. The consensus was approved by the SOCHED board for publication.


Asunto(s)
Consenso , Glándula Tiroides/diagnóstico por imagen , Glándula Tiroides/patología , Nódulo Tiroideo/diagnóstico , Biopsia con Aguja Fina , Chile , Humanos , Medición de Riesgo , Factores de Riesgo
4.
Rev Med Chil ; 141(12): 1506-11, 2013 Dec.
Artículo en Español | MEDLINE | ID: mdl-24728426

RESUMEN

BACKGROUND: Serum thyroglobulin (sTg) is an excellent marker of persistence or recurrence of disease in differentiated thyroid cancer (DTC), however its role as prognostic factor has not been fully established. AIM: To assess the value of the preablative thyroglobulin (pTg) as predictor of disease-free survival in DTC. PATIENTS AND METHODS: Retrospective study of 104 patients with low and intermediate risk DTC subjected to total thyroidectomy and 131iodine ablation. TSH, pTg and thyroglobulin antibodies (AbTg) were determined by chemiluminescence. Patients with distant metastases or presence of AbTg were excluded. Results were analyzed using receiving operating characteristic (ROC) curves. RESULTS: During the 40 ± 29 months of follow-up (range 6-132), 14 of 104 (13%) patients had recurrence of disease. pTg was an independent indicator to predict disease-free survival. Using a pTg cutoff of < 10 ng/ml the negative predictive value was 99%, sensitivity 93%, specificity 82%, positive likelihood ratio (LR) 5.2 and negative LR 0,087. CONCLUSIONS: pTg value is useful as a prognostic marker in predicting disease-free survival in DTC patients with low or intermediate risk of recurrence.


Asunto(s)
Biomarcadores de Tumor/sangre , Carcinoma/terapia , Recurrencia Local de Neoplasia/sangre , Tiroglobulina/sangre , Neoplasias de la Tiroides/terapia , Adulto , Anciano , Carcinoma/sangre , Carcinoma Papilar , Chile , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Radioisótopos de Yodo/uso terapéutico , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Pronóstico , Curva ROC , Estudios Retrospectivos , Cáncer Papilar Tiroideo , Neoplasias de la Tiroides/sangre , Tiroidectomía/métodos , Adulto Joven
5.
Arch Endocrinol Metab ; 67(3): 348-354, 2023 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-36651709

RESUMEN

Objective: Follicular thyroid carcinoma (FTC) is less frequent but has a worse prognosis than papillary carcinoma. The available evidence on pre-operative characteristics of FTC is controversial. Our objective was to characterize the clinical, ultrasound and histopathological presentation of FTC patients treated Chile. Subjects and methods: Retrospective analysis of 97 patients treated for FTC in 6 large centers in Chile. We analyzed their ultrasonographic features and classified the nodules according to ATA risk of malignancy and TI-RADS score, as well as the cytological findings according to the Bethesda system. We described their clinical and histopathological findings at diagnosis and classified their risk of recurrence and mortality according to ATA 2015 recurrence risk category and the eighth edition of the AJCC/UICC staging system, respectively. Results: Median age was 48 years and 73.2% were females. The median diameter was 38.8 mm; only 9.5% of them were microtumors. According to ATA risk of malignancy, 86% of the nodules were low or intermediate suspicious, while 78% were category 3 or 4A nodules according to the TI-RADS. Regarding the Bethesda system, 65.9% had indeterminate cytology (20.6% category III and 45.3% category IV). At histological examination, most were minimally-invasive and angio-invasive tumors with less than 4 foci (54.7% and 28.4% respectively). More than 90% of FTC were unifocal and there was no lymphovascular or extrathyroidal invasion or lymph node involvement. Four patients (4.1%) had distant metastases at diagnosis. Most patients (95%) had stage I or II disease according to the AJCC/UICC staging system, while the risk of recurrence was low at 51.5% when using the ATA risk of recurrence scale. Conclusion: At diagnosis, most FTCs were nodules of low or intermediate suspicion at ultrasound, nearly two thirds had indeterminate cytology according to the Bethesda system, and nearly 50% of them were of low risk of recurrence.


Asunto(s)
Adenocarcinoma Folicular , Neoplasias de la Tiroides , Nódulo Tiroideo , Femenino , Humanos , Persona de Mediana Edad , Masculino , Neoplasias de la Tiroides/patología , Estudios Retrospectivos , Chile , Adenocarcinoma Folicular/diagnóstico por imagen , Ultrasonografía , Nódulo Tiroideo/patología
6.
Artículo en Inglés | MEDLINE | ID: mdl-22474515

RESUMEN

Introduction. Several studies demonstrated that anti-inflammatory remedies exhibit excellent anti-neoplastic properties. An extract of Pluchea odorata (Asteraceae), which is used for wound healing and against inflammatory conditions, was fractionated and properties correlating to anti-neoplastic and wound healing effects were separated. Methods. Up to six fractionation steps using silica gel, Sephadex columns, and distinct solvent systems were used, and eluted fractions were analysed by thin layer chromatography, apoptosis, and proliferation assays. The expression of oncogenes and proteins regulating cell migration was investigated by immunoblotting after treating HL60 cells with the most active fractions. Results. Sequential fractionations enriched anti-neoplastic activities which suppressed oncogene expression of JunB, c-Jun, c-Myc, and Stat3. Furthermore, a fraction (F4.6.3) inducing or keeping up expression of the mobility markers MYPT, ROCK1, and paxillin could be separated from another fraction (F4.3.7), which inhibited these markers. Conclusions. Wound healing builds up scar or specific tissue, and hence, compounds enhancing cell migration support this process. In contrast, successful anti-neoplastic therapy combats tumour progression, and thus, suppression of cell migration is mandatory.

7.
Polymers (Basel) ; 14(12)2022 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-35745939

RESUMEN

Heterogeneity of kraft lignin is one of the main limitations for the development of high-performance applications. Therefore, refining lignin using organic solvents is a promising strategy to obtain homogenous fractions with controlled quality in terms of structure and properties. In this work, one-step refining processes for hardwood kraft lignin using nine organic solvents of different chemical nature and polarity were carried out with the aim of investigating and understanding the effect of the type of organic solvent on the quality of resulting fractions. Structural features of both soluble and insoluble lignin fractions were assessed by GPC, Py-GC-MS, and FTIR linked to PCA analysis. Moreover, functional properties such as physical appearance, hygroscopicity, antioxidant capacity, and thermal properties were evaluated. The results evidenced the relationship between the nature and polarity of the solvents and the properties of the obtained soluble and insoluble fractions.

8.
Microbiologyopen ; 11(5): e1326, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36314751

RESUMEN

Five yeast fungi strains (i.e., two Cryptococcus albidus, one Candida guillermondii, and two Candida tropicalis) were isolated from sugarcane and tested for their use of lignin as sole carbon source and their potential to grow in the presence of phenol and phenol derivatives (i.e., pentachlorophenol and p-nitrophenol). The full set of isolated yeasts showed ligninolytic activity, achieving at least 36% lignin degradation after 25 days. The C. albidus JS-B1 strain had the highest ligninolytic activity, achieving 27% lignin degradation within 4 days. This increased activity was associated with the production of ligninolytic laccase enzymes. All the tested yeast fungi strains showed growth in the presence of high concentrations of phenolic compounds (i.e., 900 mg/L phenol, 200 mg/L p-nitrophenol, 50 mg/L pentachlorophenol) and showed significant potential for lignin and lignin by-product degradation. Each of these five strains has the potential to be used in biological treatment processes for contaminated effluents from paper pulping and bleaching or phenol and phenol-derivative biodegradation processes for other industrial wastewater effluents.


Asunto(s)
Lignina , Pentaclorofenol , Lignina/metabolismo , Pentaclorofenol/metabolismo , Nitrofenoles/metabolismo , Levaduras/metabolismo , Fenol/metabolismo , Biodegradación Ambiental , Fenoles/metabolismo
9.
Rev Med Chil ; 139(11): 1475-80, 2011 Nov.
Artículo en Español | MEDLINE | ID: mdl-22446654

RESUMEN

Paragangliomas are tumors arising from sympathetic and parasympathetic tissues. The classic associated syndromes are neurofibromatosis type 1, multiple endocrine neoplasia type 2 and von Hippel-Lindau. Germline mutations of succinate dehydrogenase subunits genes, are associated with familial paraganglioma syndromes 1,2,3 and 4. We report a 29-year-old woman with a family background of pheochromocytoma and history of paroxysmal headache, nausea, sweating, palpitations, associated with severe hypertension. The patient had elevated plasma noradrenalin and urinary normetanephrines. Imaging studies revealed three retroperitoneal extra-adrenal masses. The clinical and laboratory study of classic syndromes associated with paraganglioma was negative. The patient was operated and the pathological study of the surgical specimen was consistent with paragangliomas. The genetic study showed a mutation in the SDHB succinate dehydrogenase gen, Exon 2 of CCTCA c.300_304 (p.P56delYfsX5).


Asunto(s)
Neoplasias de las Glándulas Suprarrenales/genética , Mutación/genética , Paraganglioma/genética , Succinato Deshidrogenasa/genética , Adulto , Femenino , Humanos , Linaje
10.
Rev Med Chil ; 139(9): 1196-200, 2011 Sep.
Artículo en Español | MEDLINE | ID: mdl-22215400

RESUMEN

Addisonian crisis as a first manifestation of metastatic disease secondary to cancer is uncommon. We report a 63-year-old man with a history of one year of fatigue, weakness, weight loss and repeated symptomatic hypoglycemia. The cortisol stimulation test with ACTH confirmed primary adrenal insufficiency. While receiving adequate treatment with oral hydrocortisone, he presented an adrenal crisis that was treated properly. A CT scan of the lung demonstrated a nodule in the upper right lobe and bilateral adrenal tumors. The biopsy of the lesion revealed a lung adenocarcinoma. The staging with positron emission tomography using 18 fluoroglucose (PET/CT18F- FDG) showed hypermetabolic uptake in the primary lung tumor and in both adrenal glands, suggesting metastatic implants.


Asunto(s)
Enfermedad de Addison/etiología , Adenocarcinoma/secundario , Neoplasias de las Glándulas Suprarrenales/secundario , Neoplasias Pulmonares , Enfermedad de Addison/diagnóstico por imagen , Adenocarcinoma/diagnóstico , Neoplasias de las Glándulas Suprarrenales/diagnóstico por imagen , Fluorodesoxiglucosa F18 , Humanos , Neoplasias Pulmonares/diagnóstico , Masculino , Persona de Mediana Edad , Cintigrafía , Radiofármacos
11.
Int J Biol Macromol ; 168: 792-805, 2021 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-33242547

RESUMEN

Refining of industrial lignin to produce homogeneous fractions is essential for high-value applications. However, the understanding of key interactions between a variety of solvents with lignin polymer is still uncertain. In this work, single-step fractionation of industrial hardwood kraft lignin (HKL) using organic solvents of different polarities - ethanol, acetone, diethyl ether and hexane - was investigated by combining an experimental and theoretical approach. Experimental results revealed that higher polarity solvents (ethanol and acetone) exhibited higher solubility yield compared to moderate and low polarity solvents. The chemical differences between lignin fractions were proven by pyrolysis gas chromatography mass spectrometry and near infrared spectroscopy. Density functional theory (DFT) results indicated that ethanol presented higher interaction energy followed by acetone, diethyl ether and hexane, which was consistent with experimental findings. Hydrogen bond and non-covalent interaction results from DFT demonstrated that the predominant interaction was found for high polarity of ethanol over other solvents and γ-OH in the lignin model is the key site.


Asunto(s)
Fraccionamiento Químico/métodos , Lignina/química , Solventes/química , Teoría Funcional de la Densidad , Cromatografía de Gases y Espectrometría de Masas , Enlace de Hidrógeno , Peso Molecular , Pirólisis , Solubilidad
12.
Thyroid ; 30(5): 704-712, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-31910118

RESUMEN

Background: Although most thyroid nodules with indeterminate cytology are benign, in most of the world, surgery remains as the most frequent diagnostic approach. We have previously reported a 10-gene thyroid genetic classifier, which accurately predicts benign thyroid nodules. The assay is a prototype diagnostic kit suitable for reference laboratory testing and could potentially avoid unnecessary diagnostic surgery in patients with indeterminate thyroid cytology. Methods: Classifier performance was tested in two independent, ethnically diverse, prospective multicenter trials (TGCT-1/Chile and TGCT-2/USA). A total of 4061 fine-needle aspirations were collected from 15 institutions, of which 897 (22%) were called indeterminate. The clinical site was blind to the classifier score and the clinical laboratory blind to the pathology report. A matched surgical pathology and valid classifier score was available for 270 samples. Results: Cohorts showed significant differences, including (i) clinical site patient source (academic, 43% and 97% for TGCT-1 and -2, respectively); (ii) ethnic diversity, with a greater proportion of the Hispanic population (40% vs. 3%) for TGCT-1 and a greater proportion of African American (11% vs. 0%) and Asian (10% vs. 1%) populations for TGCT-2; and (iii) tumor size (mean of 1.7 and 2.5 cm for TGCT-1 and -2, respectively). Overall, there were no differences in the histopathological profile between cohorts. Forty-one of 155 and 45 of 115 nodules were malignant (cancer prevalence of 26% and 39% for TGCT-1 and -2, respectively). The classifier predicted 37 of 41 and 41 of 45 malignant nodules, yielding a sensitivity of 90% [95% confidence interval; CI 77-97] and 91% [95% CI 79-98] for TGCT-1 and -2, respectively. One hundred one of 114 and 61 of 70 nodules were correctly predicted as benign, yielding a specificity of 89% [95% CI 82-94] and 87% [95% CI 77-94], respectively. The negative predictive values for TGCT-1 and TGCT-2 were 96% and 94%, respectively, whereas the positive predictive values were 74% and 82%, respectively. The overall accuracy for both cohorts was 89%. Conclusions: Clinical validation of the classifier demonstrates equivalent performance in two independent and ethnically diverse cohorts, accurately predicting benign thyroid nodules that can undergo surveillance as an alternative to diagnostic surgery.


Asunto(s)
Glándula Tiroides/patología , Neoplasias de la Tiroides/genética , Nódulo Tiroideo/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Biopsia con Aguja Fina , Citodiagnóstico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Sensibilidad y Especificidad , Neoplasias de la Tiroides/patología , Nódulo Tiroideo/patología , Adulto Joven
13.
Int J Oncol ; 34(4): 1117-28, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19287970

RESUMEN

Many traditional healing plants successfully passed several hundred years of empirical testing against specific diseases and thereby demonstrating that they are well tolerated in humans. Although quite a few ethno-pharmacological plants are applied against a variety of conditions there are still numerous plants that have not been cross-tested in diseases apart from the traditional applications. Herein we demonstrate the anti-neoplastic potential of two healing plants used by the Maya of the Guatemala/Belize area against severe inflammatory conditions such as neuritis, rheumatism, arthritis, coughs, bruises and tumours. Phlebodium decumanum and Pluchea odorata were collected, dried and freeze dried, and extracted with five solvents of increasing polarity. We tested HL-60 and MCF-7 cells, the inhibition of proliferation and the induction of cell death were investigated as hallmark endpoints to measure the efficiency of anti-cancer drugs. Western blot and FACS analyses elucidated the underlying mechanisms. While extracts of P. decumanum showed only moderate anti-cancer activity and were therefore not further analysed, particularly the dichloromethane extract of P. odorata inhibited the cell cycle in G2-M which correlated with the activation of checkpoint kinase 2, and down-regulation of Cdc25A and cyclin D1 as well as inactivation of Erk1/2. In HL-60 and MCF-7 cells this extract was a very strong inducer of cell death activating caspase-3 followed by PARP signature type cleavage. The initiating death trigger was likely the stabilization of microtubules monitored by the rapid acetylation of alpha-tubulin, which was even more pronounced than that triggered by taxol. The dichloromethane extract of P. odorata contains apolar constituents which inhibit inflammatory responses and exhibit anti-cancer activity. The strong proapoptotic potential warrants further bioassay-guided fractionation to discover and test the active principle(s).


Asunto(s)
Antineoplásicos/farmacología , Extractos Vegetales/farmacología , Asteraceae , Bisbenzimidazol/farmacología , Línea Celular Tumoral , Separación Celular , Ensayos de Selección de Medicamentos Antitumorales , Selectina E/biosíntesis , Ensayo de Inmunoadsorción Enzimática , Etnofarmacología/métodos , Citometría de Flujo , Guatemala , Células HL-60 , Humanos , Técnicas In Vitro , Fracciones Subcelulares
14.
Zootaxa ; 4461(3): 399-410, 2018 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-30314075

RESUMEN

A new troglobitic species of the genus Antillobisium is described from Sancti Spiritus province, Cuba. Antillobisium tomasi n. sp. is the third known species of the genus and is well characterized by its large size and extremely slender appendages. Biogeographical and ecological considerations on the genus are given.


Asunto(s)
Arácnidos , Ecología , Animales , Cuba
15.
Integr Comp Biol ; 58(4): 640-653, 2018 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-29917089

RESUMEN

The advent of high-throughput sequencing (HTS) technologies has revolutionized the way we understand the transformation of genetic information into morphological traits. Elucidating the network of interactions between genes that govern cell differentiation through development is one of the core challenges in genome research. These networks are known as developmental gene regulatory networks (dGRNs) and consist largely of the functional linkage between developmental control genes, cis-regulatory modules, and differentiation genes, which generate spatially and temporally refined patterns of gene expression. Over the last 20 years, great advances have been made in determining these gene interactions mainly in classical model systems, including human, mouse, sea urchin, fruit fly, and worm. This has brought about a radical transformation in the fields of developmental biology and evolutionary biology, allowing the generation of high-resolution gene regulatory maps to analyze cell differentiation during animal development. Such maps have enabled the identification of gene regulatory circuits and have led to the development of network inference methods that can recapitulate the differentiation of specific cell-types or developmental stages. In contrast, dGRN research in non-classical model systems has been limited to the identification of developmental control genes via the candidate gene approach and the characterization of their spatiotemporal expression patterns, as well as to the discovery of cis-regulatory modules via patterns of sequence conservation and/or predicted transcription-factor binding sites. However, thanks to the continuous advances in HTS technologies, this scenario is rapidly changing. Here, we give a historical overview on the architecture and elucidation of the dGRNs. Subsequently, we summarize the approaches available to unravel these regulatory networks, highlighting the vast range of possibilities of integrating multiple technical advances and theoretical approaches to expand our understanding on the global gene regulation during animal development in non-classical model systems. Such new knowledge will not only lead to greater insights into the evolution of molecular mechanisms underlying cell identity and animal body plans, but also into the evolution of morphological key innovations in animals.


Asunto(s)
Regulación del Desarrollo de la Expresión Génica , Redes Reguladoras de Genes , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Invertebrados/genética , Vertebrados/genética , Animales , Invertebrados/crecimiento & desarrollo , Modelos Animales , Vertebrados/crecimiento & desarrollo
16.
Arch. endocrinol. metab. (Online) ; 67(3): 348-354, June 2023. tab
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1429754

RESUMEN

ABSTRACT Objective: Follicular thyroid carcinoma (FTC) is less frequent but has a worse prognosis than papillary carcinoma. The available evidence on pre-operative characteristics of FTC is controversial. Our objective was to characterize the clinical, ultrasound and histopathological presentation of FTC patients treated Chile. Subjects and methods: Retrospective analysis of 97 patients treated for FTC in 6 large centers in Chile. We analyzed their ultrasonographic features and classified the nodules according to ATA risk of malignancy and TI-RADS score, as well as the cytological findings according to the Bethesda system. We described their clinical and histopathological findings at diagnosis and classified their risk of recurrence and mortality according to ATA 2015 recurrence risk category and the eighth edition of the AJCC/UICC staging system, respectively. Results: Median age was 48 years and 73.2% were females. The median diameter was 38.8 mm; only 9.5% of them were microtumors. According to ATA risk of malignancy, 86% of the nodules were low or intermediate suspicious, while 78% were category 3 or 4A nodules according to the TI-RADS. Regarding the Bethesda system, 65.9% had indeterminate cytology (20.6% category III and 45.3% category IV). At histological examination, most were minimally-invasive and angio-invasive tumors with less than 4 foci (54.7% and 28.4% respectively). More than 90% of FTC were unifocal and there was no lymphovascular or extrathyroidal invasion or lymph node involvement. Four patients (4.1%) had distant metastases at diagnosis. Most patients (95%) had stage I or II disease according to the AJCC/UICC staging system, while the risk of recurrence was low at 51.5% when using the ATA risk of recurrence scale. Conclusions: At diagnosis, most FTCs were nodules of low or intermediate suspicion at ultrasound, nearly two thirds had indeterminate cytology according to the Bethesda system, and nearly 50% of them were of low risk of recurrence.

17.
Endocr Relat Cancer ; 25(9): 783-793, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29748190

RESUMEN

Pancreatic neuroendocrine tumors (PanNETs) are rare in von Hippel-Lindau disease (VHL) but cause serious morbidity and mortality. Management guidelines for VHL-PanNETs continue to be based on limited evidence, and survival data to guide surgical management are lacking. We established the European-American-Asian-VHL-PanNET-Registry to assess data for risks for metastases, survival and long-term outcomes to provide best management recommendations. Of 2330 VHL patients, 273 had a total of 484 PanNETs. Median age at diagnosis of PanNET was 35 years (range 10-75). Fifty-five (20%) patients had metastatic PanNETs. Metastatic PanNETs were significantly larger (median size 5 vs 2 cm; P < 0.001) and tumor volume doubling time (TVDT) was faster (22 vs 126 months; P = 0.001). All metastatic tumors were ≥2.8 cm. Codons 161 and 167 were hotspots for VHL germline mutations with enhanced risk for metastatic PanNETs. Multivariate prediction modeling disclosed maximum tumor diameter and TVDT as significant predictors for metastatic disease (positive and negative predictive values of 51% and 100% for diameter cut-off ≥2.8 cm, 44% and 91% for TVDT cut-off of ≤24 months). In 117 of 273 patients, PanNETs >1.5 cm in diameter were operated. Ten-year survival was significantly longer in operated vs non-operated patients, in particular for PanNETs <2.8 cm vs ≥2.8 cm (94% vs 85% by 10 years; P = 0.020; 80% vs 50% at 10 years; P = 0.030). This study demonstrates that patients with PanNET approaching the cut-off diameter of 2.8 cm should be operated. Mutations in exon 3, especially of codons 161/167 are at enhanced risk for metastatic PanNETs. Survival is significantly longer in operated non-metastatic VHL-PanNETs.


Asunto(s)
Tumores Neuroendocrinos/prevención & control , Neoplasias Pancreáticas/prevención & control , Enfermedad de von Hippel-Lindau/complicaciones , Adolescente , Adulto , Anciano , Niño , Humanos , Persona de Mediana Edad , Mutación , Tumores Neuroendocrinos/etiología , Tumores Neuroendocrinos/patología , Tumores Neuroendocrinos/terapia , Neoplasias Pancreáticas/etiología , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/terapia , Sistema de Registros , Carga Tumoral , Adulto Joven , Enfermedad de von Hippel-Lindau/patología , Enfermedad de von Hippel-Lindau/terapia
18.
Materials (Basel) ; 10(5)2017 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-28772902

RESUMEN

As, in the market, poly (lactic acid) (PLA) is the most used polymer as an alternative to conventional plastics, and as functionalized chitin nanocrystals (CHNC) can provide structural and bioactive properties, their combination sounds promising in the preparation of functional nanocomposite films for sustainable packaging. Chitin nanocrystals were successfully modified via acylation using anhydride acetic and dodecanoyl chloride acid to improve their compatibility with the matrix, PLA. The nanocomposite films were prepared by extrusion/compression approach using different concentrations of both sets of functionalized CHNC. This investigation brings forward that both sets of modified CHNC act as functional agents, i.e., they slightly improved the hydrophobic character of the PLA nanocomposite films, and, very importantly, they also enhanced their antifungal activity. Nonetheless, the nanocomposite films prepared with the CHNC modified with dodecanoyl chloride acid presented the best properties.

19.
Thyroid ; 27(8): 1058-1067, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28521616

RESUMEN

BACKGROUND: In most of the world, diagnostic surgery remains the most frequent approach for indeterminate thyroid cytology. Although several molecular tests are available for testing in centralized commercial laboratories in the United States, there are no available kits for local laboratory testing. The aim of this study was to develop a prototype in vitro diagnostic (IVD) gene classifier for the further characterization of nodules with an indeterminate thyroid cytology. METHODS: In a first stage, the expression of 18 genes was determined by quantitative polymerase chain reaction (qPCR) in a broad histopathological spectrum of 114 fresh-tissue biopsies. Expression data were used to train several classifiers by supervised machine learning approaches. Classifiers were tested in an independent set of 139 samples. In a second stage, the best classifier was chosen as a model to develop a multiplexed-qPCR IVD prototype assay, which was tested in a prospective multicenter cohort of fine-needle aspiration biopsies. RESULTS: In tissue biopsies, the best classifier, using only 10 genes, reached an optimal and consistent performance in the ninefold cross-validated testing set (sensitivity 93% and specificity 81%). In the multicenter cohort of fine-needle aspiration biopsy samples, the 10-gene signature, built into a multiplexed-qPCR IVD prototype, showed an area under the curve of 0.97, a positive predictive value of 78%, and a negative predictive value of 98%. By Bayes' theorem, the IVD prototype is expected to achieve a positive predictive value of 64-82% and a negative predictive value of 97-99% in patients with a cancer prevalence range of 20-40%. CONCLUSIONS: A new multiplexed-qPCR IVD prototype is reported that accurately classifies thyroid nodules and may provide a future solution suitable for local reference laboratory testing.


Asunto(s)
Regulación Neoplásica de la Expresión Génica , Proteínas de Neoplasias/metabolismo , Glándula Tiroides/metabolismo , Neoplasias de la Tiroides/diagnóstico , Nódulo Tiroideo/diagnóstico , Biomarcadores de Tumor/metabolismo , Biopsia con Aguja Fina , Chile/epidemiología , Estudios de Cohortes , Biología Computacional , Diagnóstico Diferencial , Sistemas Especialistas , Estudios de Seguimiento , Humanos , Aprendizaje Automático , Proteínas de Neoplasias/genética , Estadificación de Neoplasias , Guías de Práctica Clínica como Asunto , Valor Predictivo de las Pruebas , Prevalencia , Estudios Prospectivos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Glándula Tiroides/patología , Neoplasias de la Tiroides/epidemiología , Neoplasias de la Tiroides/metabolismo , Neoplasias de la Tiroides/patología , Nódulo Tiroideo/epidemiología , Nódulo Tiroideo/metabolismo , Nódulo Tiroideo/patología
20.
Carbohydr Polym ; 116: 286-91, 2015 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-25458302

RESUMEN

Chitin nano-objects become more interesting and attractive material than native chitin because of their usable form, low density, high surface area and promising mechanical properties. This work suggests a straightforward and environmentally friendly method for processing chitin nanofibers using dynamic high pressure homogenization. This technique proved to be a remarkably simple way to get α-chitin into α-chitin nanofibers from yellow lobster wastes with a uniform width (bellow 100 nm) and high aspect ratio; and may contributes to a major breakthrough in chitin applications. Moreover, the resulting α-chitin nanofibers were characterized and compared with native α-chitin in terms of chemical and crystal structure, thermal degradation and antifungal activity. The biological assays highlighted that the nano nature of chitin nanofibers plays an important role in the antifungal activity against Aspergillus niger.


Asunto(s)
Antifúngicos/química , Antifúngicos/farmacología , Aspergillus niger/efectos de los fármacos , Quitina/química , Quitina/farmacología , Nanofibras/química , Animales , Anomuros/química , Aspergillus niger/crecimiento & desarrollo , Quitina/aislamiento & purificación , Industria de Alimentos , Residuos Industriales , Presión , Alimentos Marinos
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