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1.
Endocrine ; 82(3): 613-621, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37490266

RESUMEN

BACKGROUND: Familial papillary thyroid microcarcinoma (FPTMC) appears to be more aggressive than sporadic papillary thyroid microcarcinoma (SPTMC). However, there are authors who indicate that unicentric FPTMC has a similar prognosis to SPTMC. The objective is to analyze whether unicentric FPTMC has a better prognosis than multicentric FPTMC. DESIGN AND METHODS: Type of study: National multicenter longitudinal analytical observational study. STUDY POPULATION: Patients with FPTMC. STUDY GROUPS: Two groups were compared: Group A (unicentric FPTMC) vs. Group B (multicentric FPTMC). STUDY VARIABLES: It is analyzed whether between the groups there are: a) differentiating characteristics; and b) prognostic differences. STATISTICAL ANALYSIS: Cox regression analysis and survival analysis. RESULTS: Ninety-four patients were included, 44% (n = 41) with unicentric FPTMC and 56% (n = 53) with multicentric FPTMC. No differences were observed between the groups according to socio-familial, clinical or histological variables. In the group B a more aggressive treatment was performed, with higher frequency of total thyroidectomy (99 vs. 78%; p = 0.003), lymph node dissection (41 vs. 15%; p = 0.005) and therapy with radioactive iodine (96 vs. 73%; p = 0.002). Tumor stage was similar in both groups (p = 0.237), with a higher number of T3 cases in the group B (24 vs. 5%; p = 0.009). After a mean follow-up of 90 ± 68.95 months, the oncological results were similar, with a similar disease persistence rate (9 vs. 5%; p = 0.337), disease recurrence rate (21 vs. 8%; p = 0.159) and disease-free survival (p = 0.075). CONCLUSIONS: Unicentric FPTMC should not be considered as a SPTMC due to its prognosis is similar to multicentric FPTMC.


Asunto(s)
Carcinoma Papilar , Neoplasias de la Tiroides , Humanos , Neoplasias de la Tiroides/genética , Neoplasias de la Tiroides/terapia , Neoplasias de la Tiroides/patología , Radioisótopos de Yodo/uso terapéutico , Recurrencia Local de Neoplasia/tratamiento farmacológico , Carcinoma Papilar/patología , Pronóstico , Tiroidectomía/métodos , Estudios Retrospectivos
2.
Langenbecks Arch Surg ; 407(8): 3631-3642, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36251077

RESUMEN

PURPOSE: Familial papillary thyroid microcarcinoma (FPTMC) can present a more aggressive behavior than the sporadic microcarcinoma. However, few studies have analyzed this situation. The objective is to analyze the recurrence rate of FPTMC and the prognostic factors which determine that recurrence in Spain. METHODS: Spanish multicenter longitudinal analytical observational study was conducted. Patients with FPTMC received treatment with curative intent and presented cure criteria 6 months after treatment. Recurrence rate and disease-free survival (DFS) were analyzed. Two groups were analyzed: group A (no tumor recurrence) vs. group B (tumor recurrence). RESULTS: Ninety-four patients were analyzed. During a mean follow-up of 73.3 ± 59.3 months, 13 recurrences of FPTMC (13.83%) were detected and mean DFS was 207.9 ± 11.5 months. There were multifocality in 56%, bilateral thyroid involvement in 30%, and vascular invasion in 7.5%; that is to say, they are tumors with histological factors of poor prognosis in a high percentage of cases. The main risk factors for recurrence obtained in the multivariate analysis were the tumor size (OR: 2.574, 95% CI 1.210-5.473; p = 0.014) and the assessment of the risk of recurrence of the American Thyroid Association (ATA), both intermediate risk versus low risk (OR: 125, 95% CI 10.638-1000; p < 0.001) and high risk versus low risk (OR: 45.454, 95% CI 5.405-333.333; p < 0.001). CONCLUSION: FPTMC has a recurrence rate higher than sporadic cases. Poor prognosis is mainly associated with the tumor size and the risk of recurrence of the ATA.


Asunto(s)
Carcinoma Papilar , Neoplasias de la Tiroides , Humanos , Carcinoma Papilar/genética , Carcinoma Papilar/patología , Neoplasias de la Tiroides/genética , Neoplasias de la Tiroides/cirugía , Supervivencia sin Enfermedad , Pronóstico , Estudios Retrospectivos , Recurrencia Local de Neoplasia/genética , Recurrencia Local de Neoplasia/patología
3.
Med Biol Eng Comput ; 56(8): 1379-1390, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29318442

RESUMEN

The present paper aims at presenting the methodology and first results of a detection system of risk of diabetic macular edema (DME) in fundus images. The system is based on the detection of retinal exudates (Ex), whose presence in the image is clinically used for an early diagnosis of the disease. To do so, the system applies digital image processing algorithms to the retinal image in order to obtain a set of candidate regions to be Ex, which are validated by means of feature extraction and supervised classification techniques. The diagnoses provided by the system on 1058 retinographies of 529 diabetic patients at risk of having DME show that the system can operate at a level of sensitivity comparable to that of ophthalmological specialists: it achieved 0.9000 sensitivity per patient against 0.7733, 0.9133 and 0.9000 of several specialists, where the false negatives were mild clinical cases of the disease. In addition, the level of specificity reached by the system was 0.6939, high enough to screen about 70% of the patients with no evidence of DME. These values show that the system fulfils the requirements for its possible integration into a complete diabetic retinopathy pre-screening tool for the automated management of patients within a screening programme. Graphical Abstract Diagnosis system of risk of diabetic macular edema (DME) based on exudate (Ex) detection in fundus images.


Asunto(s)
Algoritmos , Retinopatía Diabética/diagnóstico , Exudados y Transudados/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador , Edema Macular/diagnóstico , Automatización , Humanos , Curva ROC , Factores de Riesgo , Sensibilidad y Especificidad
4.
Ann R Coll Surg Engl ; 96(7): e8-10, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25245714

RESUMEN

The primitive thymus and inferior parathyroid derive from the third branchial cleft. During embryonic development, these structures descend, reaching their final localisation. Third branchial cleft anomalies present usually as a fistula, abscess or cyst. However, there are no reports on parathyroid adenomas in the literature other than as a morphological possibility. We describe the case of a 47-year-old man, who had been diagnosed with arterial hypertension and who presented with a cervical mass at the edge of the lower third of the sternocleidomastoid muscle. On ultrasonography, the mass had a cystic walled appearance. Laboratory analysis only revealed an intact parathyroid hormone level of 140.5 pg/ml. Sestamibi imaging showed a probable parathyroid adenoma in the anterior mediastinum. During surgery, a tract running from beyond the superior thyroid pedicle to the superior mediastinum was dissected and removed. In the inferior end of the tract, a brown mass was visible. Pathological examination revealed a thymus cyst surrounding a parathyroid adenoma. The primal alteration was the lack of division between the thymus and inferior parathyroid gland, and the prompt prevention of their development. In the case of our patient, a parathyroid adenoma had grown by chance.


Asunto(s)
Adenoma/diagnóstico por imagen , Hiperparatiroidismo/etiología , Neoplasias de las Paratiroides/diagnóstico por imagen , Paratiroidectomía/métodos , Adenoma/complicaciones , Adenoma/cirugía , Medios de Contraste , Quistes/complicaciones , Quistes/diagnóstico por imagen , Estudios de Seguimiento , Humanos , Hiperparatiroidismo/diagnóstico por imagen , Hiperparatiroidismo/cirugía , Masculino , Persona de Mediana Edad , Neoplasias de las Paratiroides/complicaciones , Neoplasias de las Paratiroides/cirugía , Enfermedades Faríngeas/complicaciones , Enfermedades Faríngeas/diagnóstico por imagen , Enfermedades Raras , Medición de Riesgo , Tecnecio Tc 99m Sestamibi , Toracotomía/métodos , Resultado del Tratamiento , Ultrasonografía Doppler/métodos
5.
Ann R Coll Surg Engl ; 95(2): e25-6, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23484975

RESUMEN

Surgery for persistent primary hyperparathyroidism remains a major challenge for surgeons and these reoperative procedures require an experienced parathyroid surgeon. The goal of reoperative surgery is to excise the abnormal parathyroid gland(s) and limit exploration to help minimise the potential complications. At least two positive and concordant localising studies should be available before reoperation because the technical difficulties in these cases make an exact localisation necessary before surgery. We describe the placement of a metallic harpoon under ultrasonography guidance as a safe, simple and inexpensive technique for localisation of the enlarged gland prior to conservative surgery.


Asunto(s)
Adenoma/cirugía , Marcadores Fiduciales , Hiperparatiroidismo Primario/cirugía , Recurrencia Local de Neoplasia/cirugía , Neoplasias de las Paratiroides/cirugía , Paratiroidectomía/instrumentación , Enfermedad Crónica , Humanos , Masculino , Persona de Mediana Edad , Cuidados Preoperatorios/instrumentación , Reoperación/instrumentación , Ultrasonografía Intervencional
6.
J Colloid Interface Sci ; 369(1): 82-90, 2012 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-22226474

RESUMEN

The synthesis and properties of thermal/pH-sensitive core-shell copolymer nano/microgels were investigated. The crosslinked core consisted of N-isopropylacrylamide (NIPAAm) while the shell was stabilized by poly(ethylene glycol) methyl ether methacrylate (PEGMA) and 2-methacryloyloxybenzoic acid (2MBA) using a "one pot" soapless emulsion polymerization method. Monodisperse particles were produced with average hydrodynamic diameters ranging from 40 to 880 nm, as determined by dynamic light scattering (DLS) in water at 25°C, depending on the synthetic recipe used. The influence of PEGMA and 2MBA content on size and temperature transition at different pH values was studied. Zeta potential measurements and acid-base titration studies demonstrated almost complete incorporation of acid comonomer (2MBA) into the nano/microgels. Two different crosslinkers, a stable and an acid labile, were compared. The crosslinker used has a major influence on the size and charge density of the nano/microgels produced. Microscopic studies confirmed the core-shell morphology of the nano/microgels.

7.
Int J Clin Pharmacol Ther ; 48(8): 525-33, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20650044

RESUMEN

PURPOSE: A vancomycin population pharmacokinetic prediction model for adult and elderly patients was developed using NONMEM. The predictability of the model was studied and compared with ten other models. METHODS: Data were collected from routine care of 141 subjects. NONMEM was used to derive a population model. After internal evaluation using the bootstrap technique, external validation was studied using an independent dataset that consisted of 95 subjects; a statistical comparison of precision and bias was conducted. RESULTS: A two-compartment open model was derived with body weight, age, and CLcr as covariates. The bootstrap process showed stability of the model. A comparison of subjects older and younger than 65 years found that the older group had a mean clearance of 2.24 (+/- 1.2) l/h compared to 4.03 (+/- 1.7) l/h, and a peripheral volume of 43.7 (+/- 5.1) l compared to 28.4 (+/- 5.3) l compared to younger patients. These values were modeled using CLcr in the clearance equation and Vd as a function of age. The eleven models studied showed a bias in predicting serum concentrations from the test database that ranged from 0.35 mg/l to -5.93 mg/l. Precision ranged from 4.53 mg/l to 8.05 mg/l. Our method ranked in fourth place overall and when compared statistically its bias was different from the method that ranked in second place by -1.45 (95% CI -2.46, -0.42; p = 0.005), and different from all the methods that ranked worse. The only difference in precision was with the method that ranked in eleventh place with a relative precision of 0.49 (95% CI 0.27, 0.70; p < 0.001). CONCLUSIONS: A two-compartment open model fitted the data with weight, age, and CLcr as covariates. The derived method ranked in fourth place overall. The two-compartment nature of two of the equations studied did not provide an advantage. A future study with more data in the distribution phase could provide a model with better predictability.


Asunto(s)
Antibacterianos/farmacocinética , Modelos Biológicos , Vancomicina/farmacocinética , Adulto , Factores de Edad , Anciano , Sesgo , Peso Corporal , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dinámicas no Lineales , Estudios Retrospectivos , Distribución Tisular
8.
Biomaterials ; 22(9): 957-61, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11311014

RESUMEN

The bioadhesive properties of the hydrophobic, basic polyelectrolyte hydrogel disks containing crosslinked N,N-dimethylaminoethyl methacrylate-co-methyl methacrylate 30/70mol% were evaluated in vitro using gastric (pH 1.2), sublingual (pH 6.5), vaginal (pH 4.0) and intestinal (pH 7.5) pig's mucosas. Adhesive strength was measured using a modified Du Noüy tensiometer by measuring the force of detachment between a gel disk and the respective mucosa. The effect of crosslinker content in the gel was evaluated. It was found an increase in the adhesive strength with the increase of crosslinker content in the pH range of 4.0-7.5. For the evaluation at pH 1.2 (gastric mucosa) the opposite behavior was observed. The results indicate that initial bioadhesive contact may be the result of surface energy effects and/or electrostatic interactions of oppositely charged groups between mucin and the gel. In some cases, mucus dehydration may also be involved. When the gel is swollen, chain interpenetration also plays a roll in the bioadhesive interaction. The gels presented bioadhesive forces in gastric and vaginal mucosas (acidic medium), similar to the adhesive forces of well-known bioadhesives such as hydroxymethylcellulose and sodium alginate to the intestinal mucosa. The results indicate that hydrophobic polybasic gels present bioadhesive properties that make them suitable for site specific, pH controlled drug delivery.


Asunto(s)
Metacrilatos/farmacología , Metilmetacrilato/farmacología , Adhesivos Tisulares/farmacología , Animales , Femenino , Concentración de Iones de Hidrógeno , Técnicas In Vitro , Cinética , Microscopía Electrónica , Porcinos
9.
Eur J Biochem ; 268(5): 1323-31, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11231284

RESUMEN

The nitrogen-fixing, symbiotic root-nodule forming bacterium Bradyrhizobium japonicum USDA 110 contained gammacerane derivatives next to triterpenoids of the hopane series. Diploptene, diplopterol, 2 beta-methyldiplopterol, aminobacteriohopanetriol and adenosylhopane were accompanied by tetrahymanol and the corresponding novel methylated homologues 2 beta-methyltetrahymanol, 20 alpha-methyltetrahymanol, and 2 beta,20 alpha-dimethyltetrahymanol. Incorporation of [(2)H(3)]methyl-L-methionine indicated that the additional methyl groups originated from methionine, probably with S-adenosylmethionine acting as methyl donor, with retention of the three deuterium atoms. The simultaneous presence of hopane and gammacerane derivatives seems a characteristic feature of the genus Bradyrhizobium and the phylogenetically closely related Rhodopseudomonas palustris.


Asunto(s)
Bradyrhizobium/química , Triterpenos/metabolismo , Bradyrhizobium/metabolismo , Cromatografía en Capa Delgada , Ciclización , Deuterio/metabolismo , Cromatografía de Gases y Espectrometría de Masas , Liasas/metabolismo , Espectroscopía de Resonancia Magnética , Metionina/análogos & derivados , Metionina/metabolismo , Metilación , Filogenia , Fosfatos de Poliisoprenilo/metabolismo , Rhodopseudomonas/química , Rhodopseudomonas/metabolismo , S-Adenosilmetionina/metabolismo , Simbiosis , Triterpenos/química
10.
Planta ; 211(1): 62-71, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10923704

RESUMEN

The mpi gene encodes a maize proteinase inhibitor (MPI) protein whose mRNA accumulates in response to mechanical wounding. In this study, mpi gene expression in response to different types of damage was investigated. In mechanically damaged leaves of maize (Zea mays L.), mpi mRNA accumulation was affected by the degree of damage inflicted on the leaf. Consecutive wounds resulted in higher levels of mpi transcripts. The MPI protein was expressed in Escherichia coli and purified. Polyclonal antibodies were then produced and used to study MPI accumulation in insect-wounded and mechanically wounded maize leaves. When larvae of the lepidopteran insect Spodoptera littoralis were fed on maize leaves, MPI accumulated in tissues adjacent to the wound site. The level of inhibitor accumulation was higher in leaves chewed by larvae than in leaves that had been damaged mechanically. Longer feeding periods also resulted in higher levels of MPI accumulation. Additionally, the inhibitory properties of MPI toward mammalian and insect digestive serine proteinases were determined. Contrary to the majority of the plant proteinase inhibitors described, MPI is an inhibitor of mammalian elastase that only weakly inhibits mammalian chymotrypsin. However, both elastase and chymotrypsin-like activities from the larval midgut of S. littoralis were effectively inhibited by MPI. We discuss these results with regard to the function and evolution of plant proteinase inhibitors. The availability of a plant proteinase inhibitor which is able to inhibit the two types of insect digestive proteinase, elastase and chymotrypsin, might be useful for engineering protection against lepidopteran insect pests in transgenic plants.


Asunto(s)
Inhibidores de Proteasas/metabolismo , Spodoptera/enzimología , Zea mays/enzimología , Secuencia de Aminoácidos , Animales , Hojas de la Planta , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Zea mays/fisiología
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