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1.
Contrib Mineral Petrol ; 172(11): 98, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-32009663

RESUMEN

St. Kitts lies in the northern Lesser Antilles, a subduction-related intraoceanic volcanic arc known for its magmatic diversity and unusually abundant cognate xenoliths. We combine the geochemistry of xenoliths, melt inclusions and lavas with high pressure-temperature experiments to explore magma differentiation processes beneath St. Kitts. Lavas range from basalt to rhyolite, with predominant andesites and basaltic andesites. Xenoliths, dominated by calcic plagioclase and amphibole, typically in reaction relationship with pyroxenes and olivine, can be divided into plutonic and cumulate varieties based on mineral textures and compositions. Cumulate varieties, formed primarily by the accumulation of liquidus phases, comprise ensembles that represent instantaneous solid compositions from one or more magma batches; plutonic varieties have mineralogy and textures consistent with protracted solidification of magmatic mush. Mineral chemistry in lavas and xenoliths is subtly different. For example, plagioclase with unusually high anorthite content (An≤100) occurs in some plutonic xenoliths, whereas the most calcic plagioclase in cumulate xenoliths and lavas are An97 and An95, respectively. Fluid-saturated, equilibrium crystallisation experiments were performed on a St. Kitts basaltic andesite, with three different fluid compositions (XH2O = 1.0, 0.66 and 0.33) at 2.4 kbar, 950-1025 °C, and fO2 = NNO - 0.6 to NNO + 1.2 log units. Experiments reproduce lava liquid lines of descent and many xenolith assemblages, but fail to match xenolith and lava phenocryst mineral compositions, notably the very An-rich plagioclase. The strong positive correlation between experimentally determined plagioclase-melt KdCa-Na and dissolved H2O in the melt, together with the occurrence of Al-rich mafic lavas, suggests that parental magmas were water-rich (> 9 wt% H2O) basaltic andesites that crystallised over a wide pressure range (1.5-6 kbar). Comparison of experimental and natural (lava, xenolith) mafic mineral composition reveals that whereas olivine in lavas is predominantly primocrysts precipitated at low-pressure, pyroxenes and spinel are predominantly xenocrysts formed by disaggregation of plutonic mushes. Overall, St. Kitts xenoliths and lavas testify to mid-crustal differentiation of low-MgO basalt and basaltic andesite magmas within a trans-crustal, magmatic mush system. Lower crustal ultramafic cumulates that relate parental low-MgO basalts to primary, mantle -derived melts are absent on St. Kitts.

2.
Circ Cardiovasc Interv ; 12(10): e007924, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31554422

RESUMEN

BACKGROUND: Recent trials suggest that complete revascularization in patients with acute ST-segment-elevation myocardial infarction and multivessel disease is associated with better outcomes than infarct-related artery (IRA)-only revascularization. There are different methods to select non-IRA lesions for revascularization procedures. We assessed the clinical outcomes of complete angiographically guided revascularization versus stress echocardiography-guided revascularization in patients with ST-segment-elevation myocardial infarction. METHODS: We performed a randomized clinical trial in patients with multivessel disease who underwent a successful percutaneous coronary intervention of the IRA to test differences in prognosis (composite end point included cardiovascular mortality, nonfatal reinfarction, coronary revascularization, and readmission for heart failure after 12 months of follow-up) between complete angiographically guided revascularization (n=154) or stress echocardiography-guided revascularization (n=152) of the non-IRA lesions in an elective procedure before hospital discharge. RESULTS: The trial was prematurely stopped after the inclusion of 77% of the planned study population. As many as 152 (99%) patients in the complete revascularization group and 44 (29%) patients in the selective revascularization group required a percutaneous coronary intervention procedure of a non-IRA lesion before discharge. The primary end point occurred in 21 (14%) patients of the stress echocardiography-guided revascularization group and 22 (14%) patients of the complete angiographically guided revascularization group (hazard ratio, 0.95; 95% CI, 0.52-1.72; P=0.85). CONCLUSIONS: In patients with ST-segment-elevation myocardial infarction and multivessel disease, stress echocardiography-guided revascularization may not be significantly different to complete angiographically guided revascularization, thereby reducing the need for elective revascularization before hospital discharge. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov. Unique identifier: NCT01179126.


Asunto(s)
Angiografía Coronaria , Enfermedad de la Arteria Coronaria/terapia , Vasos Coronarios/diagnóstico por imagen , Ecocardiografía de Estrés , Intervención Coronaria Percutánea , Infarto del Miocardio con Elevación del ST/terapia , Anciano , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/mortalidad , Enfermedad de la Arteria Coronaria/fisiopatología , Vasos Coronarios/fisiopatología , Terminación Anticipada de los Ensayos Clínicos , Prueba de Esfuerzo , Femenino , Insuficiencia Cardíaca/mortalidad , Insuficiencia Cardíaca/fisiopatología , Insuficiencia Cardíaca/terapia , Humanos , Masculino , Persona de Mediana Edad , Readmisión del Paciente , Intervención Coronaria Percutánea/efectos adversos , Intervención Coronaria Percutánea/mortalidad , Valor Predictivo de las Pruebas , Recurrencia , Factores de Riesgo , Infarto del Miocardio con Elevación del ST/diagnóstico por imagen , Infarto del Miocardio con Elevación del ST/mortalidad , Infarto del Miocardio con Elevación del ST/fisiopatología , España , Factores de Tiempo , Resultado del Tratamiento
3.
Front Psychiatry ; 9: 19, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29472875

RESUMEN

OBJECTIVE: Comorbidity between personality disorders (PD) and substance-use disorders (SUD) is one of the most common findings in the psychiatric field. The patients with Cluster C disorders present maladjustment traits often characterized by high levels of anxiety. The main aim of this study was to find evidences about higher anxiety and depression prevalence on Cluster C than others Clusters, analyzing similarities and differences within, with other Cluster A and B PD patients and patients without PD. METHOD: A total of 822 substance dependent patients (ages18-78; Mean = 38.35, SD = 10.14) completed the structured clinical interview for DSM-IV Axis I and Axis II disorders, Beck Depression Inventory, and State-Trait Anxiety Inventory. RESULTS: Results supported poly-consumption in Cluster C patients, being greater alcohol consumption as well as abuse of both stimulants and depressants. Anxiety and depression did not show just one pattern for all patients with SUD-Cluster C PD. There was a relation between anxiety and depression for all the groups except for the Dependent-PD. CONCLUSION: Interventions should focus on aspects like depression and anxiety more than on the substance consumed.

4.
Surgery ; 163(2): 381-387, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29146232

RESUMEN

BACKGROUND: Parathyroidectomy (PTx) decreases the mortality rate of refractory secondary hyperparathyroidism (rSHP) due to chronic kidney disease. A consensus regarding which techniques of PTx are associated with better outcomes is not available. The aims of this study are to evaluate the clinical and laboratory evolution of 49 hemodialysis patients with rSHP who underwent PTx using different techniques. METHODS: Patients underwent subtotal PTx (sub-PTx) or total PTx with autotransplantation (AT) of 45 (PTx-AT45) or 90 parathyroid fragments (PTx-AT90) and were followed for 12 months. We analyzed the expression of proliferating cell nuclear antigen (PCNA), calcium-sensing receptor (CasR), vitamin D receptor (VDR), fibroblast growth factor receptor-1 (FGFR1), sodium-dependent phosphate cotransporter-1 (PIT1), and Klotho in parathyroid glands. RESULTS: Baseline median serum intact parathyroid hormone (iPTH) levels were 1,466 (1,087-2,125) pg/mL; vascular calcification scores correlated with serum iPTH (r = 0.529; P = .002) and serum phosphate levels (r = 0.389; P = .028); and Klotho expression was negatively correlated with serum phosphate levels (r = -0.4; P = .01). After 12 months, serum iPTH and alkaline phosphatase levels were significantly controlled in all groups, as was bone pain. The proportions of patients with serum iPTH levels within the ranges recommended by Kidney Disease: Improving Global Outcomes were similar among the treatment groups. During the hungry bone disease (HBS), patients received 3,786 g (1,412-7,580) of elemental calcium, and a trend toward a positive correlation between the cumulative calcium load at the end of follow up and VC score post-PTx was noted (r = 0.390; P = .06). Two cases evolved to clinically uncontrolled hyperparathyroidism in the sub-PTx group. The expression patterns of PCNA, VDR, CasR, PIT1, FGFR1, and Klotho in parathyroid glands did not correlate with serum systemic iPTH levels or the duration of HBS. CONCLUSIONS: All 3 operative techniques were effective at controlling rSHP, both in clinical and laboratory terms. Neither the quantity nor quality of parathyroid fragments influenced serum systemic iPTH and AT-iPTH levels. The cumulative calcium load appeared to correlate with the VC score and may have affected its progression. The effects of phosphate restriction on Klotho expression in human parathyroid glands and the subsequent decrease in FGF23 resistance must be addressed in further studies.


Asunto(s)
Hiperparatiroidismo Secundario/cirugía , Glándulas Paratiroides/metabolismo , Glándulas Paratiroides/trasplante , Paratiroidectomía/métodos , Adulto , Calcio/sangre , Femenino , Factor-23 de Crecimiento de Fibroblastos , Glucuronidasa/metabolismo , Humanos , Hiperparatiroidismo Secundario/sangre , Fallo Renal Crónico/complicaciones , Fallo Renal Crónico/terapia , Proteínas Klotho , Masculino , Persona de Mediana Edad , Hormona Paratiroidea/sangre , Antígeno Nuclear de Célula en Proliferación/metabolismo , Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos/metabolismo , Receptores de Calcitriol/metabolismo , Receptores Sensibles al Calcio/metabolismo , Estudios Retrospectivos , Factor de Transcripción Pit-1/metabolismo , Trasplante Autólogo
5.
J Trauma Acute Care Surg ; 76(2): 353-7, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24398767

RESUMEN

BACKGROUND: The trauma service experienced preventable delays caused by an Accreditation Council for Graduate Medical Education work restrictions and a 16% increase in patient census. Furthermore, nurses needed a consistently accessible provider for the coordination of care. We hypothesized that using experienced acute care nurse practitioners (ACNPs) on the stepdown unit would improve throughput and decrease length of stay (LOS) and hospital charges. Moreover, we hypothesized that adding ACNPs would improve staff satisfaction. On December 1, 2011, the Vanderbilt University Medical Center Division of Trauma reassigned ACNPs to the stepdown area 5 days a week for a pilot program. METHODS: LOS data from December 1, 2011 through December 1, 2012 was compared with data from the same months from the previous two years and estimated hospital charges and patient days were extrapolated. Physician and nursing surveys were performed. Data from 2010 (n = 2,559) and 2011 (n= 2,671) were averaged and the mean LOS for the entire trauma service was 7.2 days. After adding an experienced ACNP, the average LOS decreased to 6.4 days, a 0.8 day reduction. Per patient, there was a $ 9,111.50 savings in hospital charges, for a reduction of $27.8 million dollars in hospital charges over the 12 month pilot program. RESULTS: A confidential survey administered to attending physicians showed that 100% agreed that a nurse practitioner in the stepdown area was beneficial and helped throughput. Dayshift nurses were surveyed, and 100% agreed or strongly agreed that the ACNPs were knowledgeable about the patient's plan of care, experienced in the care of trauma patients, and improved patient care overall. CONCLUSION: The addition of experienced ACNPs resulted in the decrease of overall trauma service LOS, saving almost $9 million in hospital charges. LEVEL OF EVIDENCE: Economic/decision study, level III.


Asunto(s)
Medicina de Emergencia , Enfermería de Urgencia , Satisfacción en el Trabajo , Tiempo de Internación/estadística & datos numéricos , Enfermeras Practicantes/provisión & distribución , Centros Traumatológicos/organización & administración , Centros Médicos Académicos/organización & administración , Análisis Costo-Beneficio , Femenino , Encuestas de Atención de la Salud , Humanos , Unidades de Cuidados Intensivos/organización & administración , Tiempo de Internación/economía , Masculino , Enfermeras Practicantes/economía , Grupo de Atención al Paciente/organización & administración , Alta del Paciente/economía , Alta del Paciente/estadística & datos numéricos , Satisfacción Personal , Pautas de la Práctica en Medicina/economía , Pautas de la Práctica en Medicina/estadística & datos numéricos , Calidad de la Atención de Salud , Recursos Humanos
6.
Transplantation ; 96(3): 290-6, 2013 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-23823648

RESUMEN

BACKGROUND: Studies that have conducted bone biopsies after kidney transplantation are scarce, and the results are conflicting. METHODS: We evaluate the bone histomorphometry, in vitro proliferation, and alkaline phosphatase expression in osteoblasts isolated from bone biopsies from 27 kidney transplant patients. The patients had preserved renal function and were treated with the same immunosuppressive therapy, receiving a minimum dose of corticosteroids. RESULTS: The biochemical analysis revealed that 41% of the patients presented with hypercalcemia, 26% presented with hypophosphatemia, and hypovitaminosis D was detected in 63%. The histomorphometric analysis showed a reduced trabecular number and increased trabecular separation, mineral apposition rate, and mineralization lag time, as well as higher osteoid surface, osteoblastic surface, resorption surface, and osteoclastic surface and a lower mineralizing surface, compared with the controls. Based on the TMV classification, bone turnover was normal in 48%, high in 26%, and low in 26% of patients. Bone mineralization was delayed in 48% of the patients, and 58% of the patients with hypovitaminosis D presented with delayed bone mineralization. Bone volume was low in 37% of the patients. The osteoblasts from patients exhibited a higher degree of proliferation compared with those from controls. CONCLUSION: Eight-two percent of our patients presented with alterations in at least one of the TMV parameters. Persistence of hyperparathyroidism, hypovitaminosis D, and immunosuppressive drugs may have influenced osteoblast function, which would explain many of the bone alterations found in these patients.


Asunto(s)
Enfermedades Óseas/etiología , Hipercalcemia/etiología , Hipofosfatemia/etiología , Trasplante de Riñón/efectos adversos , Adulto , Fosfatasa Alcalina/metabolismo , Calcificación Fisiológica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Hormona Paratiroidea/sangre , Complicaciones Posoperatorias/etiología , Vitamina D/análogos & derivados , Vitamina D/sangre
7.
Rev. bras. cir. cabeça pescoço ; 37(4): 187-190, out.-dez. 2008. ilus
Artículo en Portugués | LILACS-Express | LILACS | ID: lil-507891

RESUMEN

Introdução: Efetuado o tratamento cirúrgico do hiperparatireoidismo secundário, pode sobrevir hipoparatireoidismo. Um recurso terapêutico corrente é auto-implantar fragmentos paratireóideos criospreservados. A função do tecido criopreservado não é bem compreendida e preditores de função são de interesse. Objetivo: Analisar a relação entre o aspecto morfológico do tecido criopreservado à microscopia óptica e a função subseqüente deste tecido auto-implantado. Métodos: Análise retrospectiva do aspecto observado à microscopia óptica de alguns fragmentos de tecido implantado em pacientes com hipoparatireoidismo após paratireoidectomia total feita para tratamento de hiperplasia secundária. As imagens observadas foram correlacionadas à função do implante em dois grupos: um com microscopia normal e outro com autólise. Os níveis de hormônio da paratireóide (PTH) foram analisados um ano após o implante. O auto-implante de tecido criopreservado foi considerado funcional quando os níveis sistêmicos de PTH eram maiores que 15pg/ml. Resultados: Quinze pacientes foram incluídos no estudo. Desses, a função do implante pode ser demonstrada em seis (40%). A autólise foi achada em dois casos, ambos sem sinal de funcionamento. Em 13 pacientes, o tecido implantado era normal à microscopia óptica. Apesar dessa morfologia normal, em sete (53,8%) casos não havia funcionamento mesmo após um ano após a operação; apenas seis (46,2%) estão funcionais. Conclusões: A microscopia óptica convencional parece ter valor limitado para predizer a eventual função do tecido paratireóideo criopreservado após seu auto-implante. A autólise pode ser um indicador de má função.


Introduction: Hypoparathyroidism may ensue after the surgical treatment of secondary hyperparathyroidism. Implantation of cryopreserved parathyroid tissue is an option to revert the state of hypoparathyroidism after total parathyroidectomy for secondary hyperplasia. The function of cryopreserved tissue is not fully understood and function predictors are of interest. Objective: To analyze the relationship between optical microscopy aspect of cryopreserved tissue and its subsequent function after autograft. Methods: We analyzed retrospectively the optical microscopy findings of some fragments of implanted tissue in patients with hypoparathyroidism after total parathyroidectomy for secondary hyperplasia. These findings were correlated to the graft function. They were divided in one group with normal optical microscopy and another one with the presence of autolysis. PTH levels were analyzed one year after implant. Function of the cryopreserved graft was considered when systemic levels of PTH were greater than 15pg/ml. Results: Fifteen patients were included in this study. Of those, graft function was demonstrable in six (40%). Autolysis was found in two cases, without any sign of PTH secretion on both. In 13 patients, optical microscopy was normal. Despite this gross morphological normality, seven (53.8%) implants did not work after one year and only six (46.2%) are working. Conclusion: Conventional optical microscopy seems to play a limited role in predicting the outcome of parathyroid autografts. Autolysis may be a bad sign for future autograft function.

8.
Rev. Hosp. Clin. Fac. Med. Univ. Säo Paulo ; 44(1): 36-9, jan.-fev. 1989. tab
Artículo en Portugués | LILACS | ID: lil-72702

RESUMEN

Estudou-se a dinâmica da secreçäo in vitro da calcitonina produzida por um carcinoma medular de tireóide. Quatorze dias após cultivo do carcinoma medular de tireóide, adicionou-se cloreto de cálcio (20 mM), cloreto de magnésio (20mM), glucagon (6 x 10-6 M) e pentagastrina (3 x 10-6 M). O cloreto de sódio (20mM) foi usado como controle. A calcitonina foi dosada por radioimunoensaio, usando duplo anticorpo. A relaçäo concentraçäo de calcitonina do meio: conteúdo de proteína de cada frasco foi considerada. Notaram-se acréscimos evidentes na secreçäo decalcitonina, em relaçäo ao ensaio controle, 4 horas após a adiçäo de todos produtos testados. Os delta% em relaçäo ao experimento controle foram de 60, 264, 50 e 48, após acréscimo de magnésio, cálcio, pentagastrina e glucagon, respectivamente. O sistema montado pode ser útil no futuro para testar qumioterápicos que atuem sobre o carcinoma medular de tireóide


Asunto(s)
Humanos , Calcitonina/metabolismo , Carcinoma/metabolismo , Técnicas de Cultivo , Técnicas In Vitro , Neoplasias de la Tiroides/metabolismo , Medios de Cultivo
9.
Rev. Hosp. Clin. Fac. Med. Univ. Säo Paulo ; 40(5): 220-2, set.-out. 1985.
Artículo en Portugués | LILACS | ID: lil-27923

RESUMEN

Uma amostra de carcinoma medular de tireóide foi cultivada por 29 dias, tendo-se dosado a CT secretada para o meio de cultura a cada 24-48 h. Os níveis iniciais de CT (> 1000 pg/ml) demonstraram queda gradativa até o 20§ dia (110 pg/ml). Entre os dias 20 e 29, os níveis de CT secretada para o meio se mantiveram constantes. Esta abordagem abre uma nova oportunidade em nosso meio no estudo deste tumor e na sua confirmaçäo diagnóstica


Asunto(s)
Persona de Mediana Edad , Humanos , Masculino , Calcitonina/análisis , Carcinoma/análisis , Neoplasias de la Tiroides/análisis , Calcitonina/metabolismo , Medios de Cultivo , Técnicas de Cultivo
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