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1.
Sci Rep ; 14(1): 10793, 2024 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-38734754

RESUMEN

Iron oxide-copper-gold (IOCG) deposits are a vital source of copper and critical elements for emerging clean technologies. Andean-type IOCG deposits form in continental arcs undergoing extension, and they have a temporal relationship with magmatism although they do not exhibit a close spatial relation with the causative intrusions. The processes required to form IOCG deposits and their potential connections to iron oxide-apatite (IOA)-type mineralization remain poorly constrained, as well as the characteristics of magmatism linked to both deposit types. Here we combine zircon U-Pb geochronology with zircon trace element geochemistry of intrusive rocks associated with the Candelaria deposit, one of the world's largest IOCG deposits, to unravel distinctive signatures diagnostic of magmatic fertility. Our results reveal a marked transition in the geochemistry of intrusions in the Candelaria district, characterized by changes in the redox state, water content and temperature of magmas over time. The oldest magmatic stage (~ 128-125 Ma), prior to the formation of the Candelaria deposit, was characterized by zircon Eu/Eu* ratios of 0.20-0.42, and redox conditions of ΔFMQ - 0.4 to + 1.0. The earliest magmatic stage related to the formation of Fe-rich mineralization at Candelaria (118-115 Ma) exhibits low zircon Eu/Eu* ratios (0.09-0.18), low oxygen fugacity values (ΔFMQ ~- 1.8 to + 0.2) and relatively high crystallization temperatures. In contrast, the youngest stage at ~ 111-108 Ma shows higher zircon Eu/Eu* (~ 0.37-0.69), higher oxygen fugacity values (ΔFMQ ~ + 0.4 to + 1.3) and a decrease in crystallization temperatures, conditions that are favorable for the transport and precipitation of sulfur and chalcophile elements. We conclude that Candelaria was formed through two distinct ore-forming stages: the first associated with a reduced, high temperature, water-poor magma developed under a low tectonic stress, followed by a more oxidized, water-rich, and low temperature magmatic event related to a compressional regime. The first event led to Fe-rich and S-poor IOA-type mineralization, while the second event with geochemical signatures similar to those of porphyry copper systems, generated the Cu- and S-rich mineralization. This late stage overprinted preexisting IOA mineralization resulting in the formation of the giant Candelaria IOCG deposit.

2.
Malays Orthop J ; 15(1): 12-15, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33880142

RESUMEN

A series of mortalities among musculoskeletal tumour patients secondary to medical illnesses during the first few months of the pandemic highlighted the need to review our methods of communication with patients. Prominent among patients' concerns had been a fear of consulting at hospitals and a lack of ready access to health care. Recommendations are made for proactive consultation and patient education, identifying at-risk patients for follow-up and probing for possible co-morbidities. Telemedicine use is encouraged bearing in mind its inherent limitations. A network of physicians and pharmaceutical representatives is an added help we can offer our patients who may be isolated by community quarantine.

3.
Artículo en Inglés | WPRIM (Pacífico Occidental) | ID: wpr-913055

RESUMEN

@#A series of mortalities among musculoskeletal tumour patients secondary to medical illnesses during the first few months of the pandemic highlighted the need to review our methods of communication with patients. Prominent among patients’ concerns had been a fear of consulting at hospitals and a lack of ready access to health care. Recommendations are made for proactive consultation and patient education, identifying at-risk patients for follow-up and probing for possible co-morbidities. Telemedicine use is encouraged bearing in mind its inherent limitations. A network of physicians and pharmaceutical representatives is an added help we can offer our patients who may be isolated by community quarantine.

4.
Talanta ; 192: 374-379, 2019 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-30348405

RESUMEN

A tandem system based on the coupling of a bulk liquid membrane and a flow injection analysis for the separation, preconcentration and spectrophotometric determination of copper in saline water is presented. The ligand pyridine-2-acetaldehyde benzoylhydrazone has been used as a carrier in the liquid membrane as well as a spectrophotometric reagent for UV-VIS detection. Simultaneous and sequential experimental designs were used to optimise the chosen variables of each technique, respectively. The metal was separated and preconcentrated from the sample with an efficiency of 100.5 ±â€¯0.9% and a metal preconcentration factor of 16.1. The on-line FIA determination was accomplished after metal complexation by the reagent at pH 3. A linear response was obtained in a range from 6.9 to 984.5 µg L-1 Cu(II), providing a detection limit of 1.8 µg L-1. Saline matrix and other metal ions were not cause of interferences with relative errors below 4.6% for 50 µg L-1 of Cu(II) determination. The proposed tandem system was successfully tested using a TMDA-62 certified reference material providing a relative error of + 1.9%; it was also applied to the Cu(II) determination in coastal seawater samples with low relative errors ranging from - 3.8% to 0.0% (using DPASV as reference method).

5.
Exp Physiol ; 99(9): 1241-52, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25085845

RESUMEN

The prevention and treatment of obesity in children is based on adequate nutrition and exercise plus antihyperglycaemic drugs. Currently, the incidence of childhood obesity is aggravated in ethnicities with thrifty genotype, but there is no available information on the effects of metformin therapy. The relative effects of lifestyle and metformin on patterns of growth, fattening, metabolic status and attainment of puberty were assessed in females of an obese swine model (Iberian gilts), allocated to three experimental groups (group A, obesogenic diet and scarce exercise; group DE, adequate diet and opportunity for exercise; and group DEM, adequate diet and opportunity for exercise plus metformin). Group A evidenced high weight, corpulence and adiposity, high plasma triglycerides and impairments of glucose regulation predisposing to insulin resistance. These features were favourably modulated by adequate lifestyle (group DE), and these effects were strengthened by metformin treatment (group DEM), which induced an improvement in body development by favouring muscle deposition. However, contrary to expectations, metformin advanced the onset of puberty. Metformin treatments would have positive effects on growth patterns, adiposity and metabolic features of young females from ethnicities with thrifty genotype or developing leptin resistance, but a negative effect by advancing the attainment of puberty. This study provides a warning regarding the use of metformin, without further studies, in girls from these ethnicities.


Asunto(s)
Metabolismo Energético/efectos de los fármacos , Hipoglucemiantes/farmacología , Metformina/farmacología , Obesidad/tratamiento farmacológico , Maduración Sexual/efectos de los fármacos , Adiposidad/efectos de los fármacos , Factores de Edad , Animales , Biomarcadores/sangre , Glucemia/metabolismo , Dieta Alta en Grasa , Modelos Animales de Enfermedad , Metabolismo Energético/genética , Femenino , Genotipo , Hipoglucemiantes/toxicidad , Insulina/sangre , Resistencia a la Insulina , Imagen por Resonancia Magnética , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/crecimiento & desarrollo , Obesidad/sangre , Obesidad/genética , Obesidad/metabolismo , Obesidad/fisiopatología , Fenotipo , Medición de Riesgo , Conducta Sedentaria , Porcinos , Triglicéridos/sangre , Aumento de Peso/efectos de los fármacos
6.
J Dev Orig Health Dis ; 5(3): 248-58, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24901665

RESUMEN

The main role of early nutritional programming in the current rise of obesity and associated diseases is well known. However, translational studies are mostly based in postnatal food excess and, thus, there is a paucity of information on the phenotype of individuals with prenatal deficiencies but adequate postnatal conditions. Thus, we assessed the effects of prenatal programming (comparing descendants from females fed with a diet fulfilling 100 or only 50% of their nutritional requirements for pregnancy) on gene expression, patterns of growth and fattening, metabolic status and puberty attainment of a swine model of obesity/leptin resistance with controlled postnatal nutrition and opportunity of exercise. Maternal restriction was related to changes in the relationships among gene expression of positive (insulin-like growth factors 1 and 2) and negative (myostatin) regulators of muscle growth, with negative correlations in gilts from restricted pregnancies and positive relationships in the control group. In spite of these differences, the patterns of growth and fattening and the metabolic features during juvenile growth were similar in control gilts and gilts from restricted pregnancies. Concomitantly, there was a lack of differences in the timing of puberty attainment. However, after reaching puberty and adulthood, females from restricted pregnancies were heavier and more corpulent than control gilts, though such increases in weight and size were not accompanied by increases in adiposity. In conclusion, in spite of changes in gene expression induced by developmental programming, the propensity for higher weight and adiposity of individuals exposed to prenatal malnutrition may be modulated by controlled food intake and opportunity of physical exercise during infant and juvenile development.


Asunto(s)
Modelos Animales de Enfermedad , Leptina/sangre , Obesidad/sangre , Obesidad/terapia , Condicionamiento Físico Animal/fisiología , Fenómenos Fisiologicos de la Nutrición Prenatal/fisiología , Adiposidad/fisiología , Animales , Animales Recién Nacidos , Peso Corporal/fisiología , Femenino , Masculino , Obesidad/fisiopatología , Condicionamiento Físico Animal/métodos , Embarazo , Efectos Tardíos de la Exposición Prenatal/sangre , Efectos Tardíos de la Exposición Prenatal/fisiopatología , Porcinos
7.
Diagn Interv Imaging ; 95(9): 839-47, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24746864

RESUMEN

PURPOSES: To determine the feasibility of MRI for imaging subcutaneous and visceral adiposity in longitudinal studies in obese swine models (Iberian pig). To establish the anatomical regions of interest (ROIs) and measurement points (MPs) adequate for their evaluation through analyses on the inter-individual variability and over-time reproducibility and through the assessment of their reliability and validity by comparison with in vivo and ex vivo zoometric data. MATERIAL AND METHODS: Five male and five female pigs were used from four (live weight around 48 kg and back-fat depth around 18 mm) to eight months old (live weight 134 kg and back-fat depth around 48 mm). MRI was carried out with a Panorama 0.23T scanner (Philips Medical Systems, Best, Netherlands), using a body/spine XL coil. RESULTS: The ROIs of election for visualization of subcutaneous data are located from the cranial margin of left diaphragmatic crura to the lumbar vertebrae L3. Visceral adiposity may be equally evaluated from the vertebrae L1 to L3. CONCLUSIONS: MRI allows the evaluation of subcutaneous and visceral fatness in a single acquisition, which improves animal welfare and time- and cost-efficiency and provides an accurate, consistent and repeatable procedure for sequential studies of adiposity in obese swine.


Asunto(s)
Modelos Animales de Enfermedad , Grasa Intraabdominal/patología , Imagen por Resonancia Magnética/métodos , Obesidad/diagnóstico , Grasa Subcutánea/patología , Animales , Biometría , Estudios de Factibilidad , Femenino , Humanos , Estudios Longitudinales , Masculino , Porcinos/crecimiento & desarrollo
8.
J Oral Pathol Med ; 40(6): 441-50, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21198873

RESUMEN

Mastocytosis encompasses a group of rare clinical entities, which are characterized by an abnormal growth and, usually, low accumulation of clonal and morphologically abnormal mast cells (MCs), within one or more organs. Clinical presentations are quite variable and symptoms are usually related to the release of mast cell mediators, tissue infiltration by MC (usually in the aggressive categories of the disease), or both. Mast cells are hematopoietic-derived cells that reach phenotypic maturity in the mucosa and peripheral connective tissues. These cells play an active role both on immunologic and non-immunologic processes. Within the oral cavity, MCs reside in the connective tissues, in physiologic conditions, and their number is elevated in pathologic situations resulting from immunoinflammatory processes, such as pulpal inflammation and periodontal disease. As MCs influence so many phenomena within the oral cavity, mastocytosis may manifest itself in the oral tissues. Patients with mastocytosis should be put under special care by dental professionals, in what concerns not only general patient management, but also drug prescription, as they are particularly prone to anaphylaxis and other peri and post-operative complications. Several allergens or mast cell activation triggers such as local anesthetics, zinc oxide, eugenol, penicilins, metals and oral hygiene products are frequently administered or prescribed by dentists. Patients with mastocytosis may also require stress management, during dental consultation. This review aims to briefly summarize the potential ways in which mast cell disease may affect the oral cavity and the dental management of mastocytosis affected patients.


Asunto(s)
Atención Dental para Enfermos Crónicos , Enfermedades Maxilomandibulares/patología , Mastocitosis/patología , Enfermedades Periodontales/patología , Pulpitis/patología , Anafilaxia/etiología , Degranulación de la Célula , Liberación de Histamina , Humanos , Mediadores de Inflamación/metabolismo , Mastocitosis/complicaciones , Mastocitosis/genética , Proteínas Proto-Oncogénicas c-kit/genética
10.
Vet Rec ; 157(19): 586-9, 2005 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-16272546

RESUMEN

A previously healthy Scottish terrier developed verminous pneumonia due to Filaroides hirthi. The disease was diagnosed on the basis of cytology of a transtracheal wash, which contained 17 per cent eosinophils and a large number of parasite larvae. Treatment with 50 mg/kg bodyweight fenbendazole daily for three weeks eliminated the parasites and improved the clinical condition of the dog.


Asunto(s)
Enfermedades de los Perros/tratamiento farmacológico , Filariasis/veterinaria , Neumonía/veterinaria , Animales , Antinematodos/uso terapéutico , Enfermedades de los Perros/parasitología , Perros , Femenino , Fenbendazol/uso terapéutico , Filariasis/complicaciones , Filariasis/tratamiento farmacológico , Filarioidea/aislamiento & purificación , Neumonía/tratamiento farmacológico , Neumonía/etiología , España
13.
Bone Marrow Transplant ; 31(10): 923-5, 2003 May.
Artículo en Inglés | MEDLINE | ID: mdl-12748670

RESUMEN

Hemorrhagic cystitis (HC) is a common and sometimes life-threatening complication of hemopoietic cell transplantation (HCT) occurring in 7-52% of transplant recipients. In this setting it is usually either related to the use of cyclophosphamide or to a viral infection (BK, JC viruses and adenovirus type 11). Treatment is based on hyperhydration, platelet and blood-cell transfusions, bladder irrigation and pain management. Where these measures have failed to control HC, numerous therapeutic approaches including surgery have been tried with poor success. We report two HCT patients with severe HC successfully treated with selective embolization of the vesical arteries.


Asunto(s)
Oclusión con Balón/efectos adversos , Cistitis/etiología , Hemorragia/etiología , Enfermedad de Hodgkin/terapia , Linfoma no Hodgkin/terapia , Trasplante de Células Madre/métodos , Adulto , Angiografía , Cistitis/terapia , Femenino , Hemorragia/terapia , Humanos , Masculino , Persona de Mediana Edad , Transfusión de Plaquetas , Trasplante Autólogo/efectos adversos , Trasplante Homólogo/efectos adversos , Vejiga Urinaria/irrigación sanguínea
15.
J Ultrasound Med ; 20(1): 51-8, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11149529

RESUMEN

We assessed the usefulness of routine Doppler ultrasonography for early detection of hepatic artery thrombosis after orthotopic liver transplantation and repercussions in patient prognosis. Seventeen confirmed cases of early hepatic artery thrombosis initially diagnosed by Doppler ultrasonography (10 of them before clinical indication) were reviewed. All patients underwent Doppler ultrasonographic studies in the first 3 days after orthotopic liver transplantation. Twelve cases of hepatic artery thrombosis (70.6%) were detected by this early Doppler ultrasonography. All 10 unsuspected cases of hepatic artery thrombosis and 5 of the 7 cases diagnosed after clinical indication were treated by revascularization. Grafts were salvaged in 80% of asymptomatic patients and in 42.8% of symptomatic patients. Furthermore, biliary complications were less serious in the first group. In conclusion, Doppler ultrasonography performed routinely in the first 3 days after orthotopic liver transplantation may permit early detection of hepatic artery thrombosis, even before clinical indications. This allows hepatic artery repermeabilization before liver function damage, improving graft rescue and patient prognosis.


Asunto(s)
Arteria Hepática/diagnóstico por imagen , Hepatopatías/diagnóstico por imagen , Trasplante de Hígado/efectos adversos , Trombosis/diagnóstico por imagen , Adolescente , Adulto , Anciano , Femenino , Arteria Hepática/patología , Humanos , Hepatopatías/etiología , Trasplante de Hígado/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Radiografía , Trombosis/etiología , Ultrasonografía Doppler
16.
J Cardiovasc Surg (Torino) ; 40(4): 523-5, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10532209

RESUMEN

Arteriovenous fistula (AVF) is rarely encountered as a complication of pacemaker insertion. Percutaneous angiographic therapy of such iatrogenic fistulas can be both safe and effective, leading to important reductions in costs. A 60-year-old woman was admitted to the hospital four weeks after left subclavian pacemaker insertion complaining of signs of congestive heart failure. A loud continuous machinery bruit was heard over the left upper chest. An arteriogram revealed a false aneurysm from the LIMA, 6 mm in-diameter, with formation of an AVF between the LIMA and the left innominate vein. Embolization of the LIMA was carried out using seven Platinum coils at the level of the AVF and the false aneurysm was embolized with 3 controlled-release IDC coils. The complete occlusion of the fistula was achieved and the distal LIMA persisted patent due to the opening of collateral vessels from the intercostal arteries. AVF between the subclavian artery or its branches and the subclavian or innominate veins have been reported to be congenital, traumatic and iatrogenic (associated to central venous access to hemodynamic monitoring, dialysis, and very infrequently to pacemaker insertion) but the internal mammary arteries are only rarely involved. The course of AVF is undefined, but generally, surgical or percutaneous embolization is warranted because of the potential appearance of a great number of complications. Surgical repair is associated with significant morbidity and mortality. Whenever possible, percutaneous nonsurgical occlusion of the AVF with coil embolization is the procedure of choice, because of its high success rate and low morbidity.


Asunto(s)
Aneurisma Falso/terapia , Fístula Arteriovenosa/terapia , Venas Braquiocefálicas , Embolización Terapéutica , Arterias Mamarias , Marcapaso Artificial , Aneurisma Falso/diagnóstico por imagen , Angiografía de Substracción Digital , Fístula Arteriovenosa/diagnóstico por imagen , Venas Braquiocefálicas/diagnóstico por imagen , Venas Braquiocefálicas/lesiones , Femenino , Insuficiencia Cardíaca/diagnóstico por imagen , Insuficiencia Cardíaca/terapia , Humanos , Arterias Mamarias/diagnóstico por imagen , Arterias Mamarias/lesiones , Persona de Mediana Edad , Retratamiento
17.
Vet Radiol Ultrasound ; 39(3): 226-33, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9634192

RESUMEN

Signalment, clinical history, physical examination, clinicopathologic, radiographic and ultrasonographic findings of 10 female dogs with histologically confirmed ovarian neoplasms were reviewed. Ultrasonographic images and reports were reviewed for (1) location, size, outer margins, and echogenicity of the mass(es), (2) presence of free abdominal fluid, (3) evidence of uterine abnormalities, and (4) signs of metastatic disease. The masses were classified according to their ultrasonographic pattern in solid, solid with cystic component, and cystic. The masses were ultrasonographically reported as being of ovarian origin in eight dogs, and this origin was included in the list of differentials in the remaining two dogs. When present, abdominal effusions and uterine abnormalities were diagnosed by means of ultrasound.


Asunto(s)
Adenocarcinoma/veterinaria , Cistoadenoma/veterinaria , Enfermedades de los Perros/diagnóstico por imagen , Neoplasias Ováricas/veterinaria , Adenocarcinoma/diagnóstico por imagen , Adenocarcinoma/patología , Animales , Cistoadenoma/diagnóstico por imagen , Cistoadenoma/patología , Enfermedades de los Perros/patología , Perros , Femenino , Neoplasias Ováricas/diagnóstico por imagen , Neoplasias Ováricas/patología , Ultrasonografía
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