Management of acromegaly in Latin America: expert panel recommendations

Although there are international guidelines orienting physicians on how to manage patients with acromegaly, such guidelines should be adapted for use in distinct regions of the world. A panel of neuroendocrinologists convened in Mexico City in August of 2007 to discuss specific considerations in Latin America. Of major discussion was the laboratory evaluation of acromegaly, which requires the use of appropriate tests and the adoption of local institutional standards. As a general rule to ensure diagnosis, the patient’s GH level during an oral glucose tolerance test and IGF-1 level should be evaluated. Furthermore, to guide treatment decisions, both GH and IGF-1 assessments are required. The treatment of patients with acromegaly in Latin America is influenced by local issues of cost, availability and expertise of pituitary neurosurgeons, which should dictate therapeutic choices. Such treatment has undergone profound changes because of the introduction of effective medical interventions that may be used after surgical debulking or as first-line medical therapy in selected cases. Surgical resection remains the mainstay of therapy for small pituitary adenomas (microadenomas), potentially resectable macroadenomas and invasive adenomas causing visual defects. Radiotherapy may be indicated in selected cases when no disease control is achieved despite optimal surgical debulking and medical therapy, when there is no access to somatostatin analogues, or when local issues of cost preclude other therapies. Since not all the diagnostic tools and treatment options are available in all Latin American countries, physicians need to adapt their clinical management decisions to the available local resources and therapeutic options

Mean Platelet Volume as Prognostic Marker in Patients with Acute Coronary Syndrome

  Background: Mean platelet volume (MPV) has been described as a predictor of cardiovascular events in patients with acute coronary syndrome. However, there is limited evidence of its role as prognostic marker in elderly patients. Objective: The aim of this study was to evaluate whether MPV is an independent predictor of events during follow-up of patients over 65 years of age with acute coronary syndrome. Methods: This prospective study included patients over 65 years with ST-segment elevation or non ST-segment elevation acute coronary syndrome. They were divided into two groups: high MPV (10.9 fL- 3rd tertile) and low MPV (<10.9 fL -1st and 2nd tertile). Different clinical variables were analyzed and the TIMI and GRACE scores were calculated. The primary endpoint was the composite of all-cause mortality and cardiovascular readmission (for acute coronary syndrome, heart failure and stroke) over the follow-up period. Results: A total of 250 patients were included in the study. Mean age was 74±7 years and 44% were women. Eighty-five patients presented with high and 165 with low MPV. Median follow-up was 302 days (interquartile range 130-558) and the primary endpoint was observed in 17.6% of cases (44 patients). In the multivariate Cox regression analysis, high MPV [HR 7.23 (95% CI 2.47-11.6); p=0.001], and TIMI [HR 3.10 (95% CI 1.46-6.59); p=0.03] and GRACE [HR 1.02 (95% CI 1.01-1.07); p=0.002] high risk scores were independent predictors of the primary endpoint. The area under the curve for MPV was 0.71 (95% CI 0.59-0.82), p=0.001. Conclusions: In our population, MPV emerged as an independent predictor of the composite endpoint, adjusted for other variables as the TIMI and GRACE scores.INTRODUCCIÓN Se ha descripto al volumen plaquetario medio (VPM)  como predictor de eventos cardiovasculares en pacientes con SCA. Hay poca evidencia en pacientes añosos. El objetivo de este trabajo es evaluar si el VPM es un predictor independiente de eventos en el seguimiento en pacientes mayores de 65 años con SCA. MATERIALES Y METODOS Estudio prospectivo que incluyó pacientes mayores de 65 años con SCA con y sin elevación del ST. Se dividieron en dos grupos: VPM alto (≥ 10,9 fL- tercilo 3) y VPM bajo (<10,9 fL -tercilos 1 y 2). Se analizaron diferentes variables clínicas y se calcularon los scores TIMI y GRACE. Se consideró el punto final combinado de mortalidad global y reinternación cardiovascular (por SCA, Insuficiencia cardíaca y Stroke) en el seguimiento. RESULTADOS. Se incluyeron 250 pacientes con una edad de 74 ± 7 años, 44% mujeres. En el grupo VPM alto hubo 85 pacientes y 165 en el VPM bajo  La mediana de seguimiento fue 302 días (rango intercuartilo 130-558) y el punto primario se observó en el 17,3% (44 pacientes). En el análisis multivariado por regresión Cox el VPM alto fue predictor independiente del punto primario (HR 7,23 (IC95% 2,47-11,6), p=0,001), al igual que el TIMI alto riesgo (3,10 (IC95% 1,46-6,59), p=0,03) y el Score GRACE (1,02 (IC95% 1,01-1,07), p=0,002). El VPM presentó un ABC 0,71 (IC95%  0,59-0,82), p=0,001. CONCLUSIONES. En nuestra población el VPM se comportó como predictor independiente del punto combinado, ajustado a otras variables como el score TIMI y GRACE

Feasibility Study of an Optical Caustic Plasmonic Light Scattering Sensor for Human Serum Anti-Dengue Protein E Antibody Detection

Antibody detection and accurate diagnosis of tropical diseases is essential to help prevent the spread of disease. However, most detection methods lack cost-effectiveness and field portability, which are essential features for achieving diagnosis in a timely manner. To address this, 3D-printed oblate spheroid sample chambers were fabricated to measure green light scattering of gold nanoparticles using an optical caustic focus to detect antibodies. Scattering signals of 20–200 nm gold nanoparticles using a green laser were compared to green light emitting diode (LED) light source signals and to Mie theory. The change in signal from 60 to 120 nm decreased in the order of Mie Theory &gt; optical caustic scattering &gt; 90° scattering. These results suggested that conjugating 60 nm gold nanoparticles and using an optical caustic system to detect plasmonic light scattering, would result in a sensitive test for detecting human antibodies in serum. Therefore, we studied the light scattering response of conjugated gold nanoparticles exposed to different concentrations of anti-protein E antibody, and a feasibility study of 10 human serum samples using dot blot and a handheld optical caustic-based sensor device. The overall agreement between detection methods suggests that the new sensor concept shows promise to detect gold nanoparticle aggregation in a homogeneous assay. Further testing and protocol optimization is needed to draw conclusions on the positive and negative predictive values for this new testing system

Volcàn de Colima dome collapse of July, 2015 and associated pyroclastic density currents

During July 10th–11th 2015, Volcán de Colima, Mexico, underwent its most intense eruptive phase since its Subplinian–Plinian 1913 AD eruption. Production of scoria coincident with elevated fumarolic activity and SO2 flux indicate a significant switch of upper-conduit dynamics compared with the preceding decades of dome building and vulcanian explosions. A marked increase in rockfall events and degassing activity was observed on the 8th and 9th of July. On the 10th at 20:16 h (Local time = UTM − 6 h) a partial collapse of the dome generated a series of pyroclastic density currents (PDCs) that lasted 52 min and reached 9.1 km to the south of the volcano. The PDCs were mostly channelized by the Montegrande and San Antonio ravines, and produced a deposit with an estimated volume of 2.4 × 106 m3. Nearly 16 h after the first collapse, a second and larger collapse occurred which last 1 h 47 min. This second collapse produced a series of PDCs along the same ravines, reaching a distance of 10.3 km. The total volume calculated for the PDCs of the second event is 8.0 × 106 m3. Including associated ashfall deposits, the two episodes produced a total of 14.2 × 106 m3 of fragmentary material. The collapses formed an amphitheater-shaped crater open towards the south. We propose that the dome collapse was triggered by arrival of gas-rich magma to the upper conduit, which then boiled-over and sustained the PDCs. A juvenile scoria sample selected from the second partial dome collapse contains hornblende, yet at an order of magnitude less abundant (0.2%) than that of 1913, and exhibits reaction rims, whereas the 1913 hornblende is unreacted. At present there is no compelling petrologic evidence for imminent end-cycle activity observed at Volcán de Colima