ABSTRACT
Human activity causes vibrations that propagate into the ground as high-frequency seismic waves. Measures to mitigate the coronavirus disease 2019 (COVID-19) pandemic caused widespread changes in human activity, leading to a months-long reduction in seismic noise of up to 50%. The 2020 seismic noise quiet period is the longest and most prominent global anthropogenic seismic noise reduction on record. Although the reduction is strongest at surface seismometers in populated areas, this seismic quiescence extends for many kilometers radially and hundreds of meters in depth. This quiet period provides an opportunity to detect subtle signals from subsurface seismic sources that would have been concealed in noisier times and to benchmark sources of anthropogenic noise. A strong correlation between seismic noise and independent measurements of human mobility suggests that seismology provides an absolute, real-time estimate of human activities.
Subject(s)
Activities of Daily Living , Coronavirus Infections/epidemiology , Noise , Pneumonia, Viral/epidemiology , COVID-19 , Humans , Pandemics , QuarantineABSTRACT
In subduction zones, elevated pore fluid pressure, generally linked to metamorphic dehydration reactions, has a profound influence on the mechanical behavior of the plate interface and forearc crust through its control on effective stress. We use seismic noise-based monitoring to characterize seismic velocity variations following the 2012 Nicoya Peninsula, Costa Rica earthquake [M w (moment magnitude) 7.6] that we attribute to the presence of pressurized pore fluids. Our study reveals a strong velocity reduction (~0.6%) in a region where previous work identified high forearc pore fluid pressure. The depth of this velocity reduction is constrained to be below 5 km and therefore not the result of near-surface damage due to strong ground motions; rather, we posit that it is caused by fracturing of the fluid-pressurized weakened crust due to dynamic stresses. Although pressurized fluids have been implicated in causing coseismic velocity reductions beneath the Japanese volcanic arc, this is the first report of a similar phenomenon in a subduction zone setting. It demonstrates the potential to identify pressurized fluids in subduction zones using temporal variations of seismic velocity inferred from ambient seismic noise correlations.
Subject(s)
Environmental Monitoring/methods , Costa Rica , Earthquakes , Environment , Motion , Noise , Pressure , Volcanic EruptionsABSTRACT
OBJECTIVES: To know the factors associated to a successful result in the treatment of kidney transplant lithiasis by extracorporeal shockwave lithotripsy (ESWL). METHODS: From 850 kidney transplants performed at our center, we analyze 15 patients who developed urinary stones. Successful result by ESWL was the dependent variable, and size, location, and multiplicity of the stones were independent variables. Associations between variables were studied by the chi-square test (categorical variables) and the U-Mann Whitney test (continuous variables). RESULTS: Incidence was 1.76%. ESWL effectiveness was 87%; it was greater in solitary stones than in multiple stones (p = 0.001). No significant differences were found for stone size, although largest stones had a high risk for insertion of a nephrostomy tube (p = 0.013). Finally, ESWL was more effective for stones located at the ureteral anastomosis, although this difference was found not significant. CONCLUSIONS: The treatment of kidney transplant lithiasis by ESWL has an effectiveness of 87%. The best result was found for solitary stones located at the ureteral anastomosis.
Subject(s)
Kidney Transplantation , Lithotripsy , Postoperative Complications/therapy , Urinary Calculi/therapy , Female , Follow-Up Studies , Humans , Male , Middle Aged , PrognosisABSTRACT
OBJECTIVES: To report one case of prostatic abscess which required emergency surgical treatment because of its aggressive evolution. METHODS: We describe the case of a 61-year-old male patient who was diagnosed of prostatic abscess in the emergency room, and initially underwent conservative treatment with antibiotics and urinary diversion. Due to clinical impairment to septicemia and upper urinary tract involvement we decided to perform a surgical perineal drainage. RESULTS: The septic clinical picture resolved immediately, but he presented a prostatic-perineal fistula in the intermediate postoperative period which resolved with prolonged urinary diversion by cystotomy catheter. HIV serologies were performed considering the aggressiveness of picture; they were positive. CONCLUSIONS: We emphasize this case because of the great aggressiveness that presented, possibly due to factors such as diabetes and immunosuppression (HIV). Provided the great variety of presentations of this disease, a high degree of suspicion must be exercised for its diagnosis, and once the diagnosis is got immediate treatment is recommended. We review etiopathogenic factors, clinical findings, diagnosis and therapeutic options.
Subject(s)
Abscess/surgery , Prostatic Diseases/surgery , Pseudomonas Infections/surgery , Emergency Treatment , Female , Humans , MaleABSTRACT
OBJETIVO: Conocer qué factores se asocian a un buen resultado en el tratamiento de la litiasis urinaria en el riñón trasplantado (RT) mediante litotricia extracorpórea por ondas de choque (LEOC). MÉTODOS: Análisis de los 15 pacientes de entre los 850 RT en nuestro centro que desarrollaron litiasis. La variable dependiente es el resultado satisfactorio de la LEOC y las independientes el tamaño, la localización y la multiplicidad de la litiasis. La posible asociación se estudió mediante la prueba de ji cuadrado en las variables categóricas y la U de Mann Whitney en las variables continuas. RESULTADOS: Incidencia del 1,76 por ciento. La efectividad fue del 87 por ciento, siendo ésta superior en las litiasis únicas que en las múltiples (p=0,001). No hay diferencias significativas en cuanto al tamaño de la litiasis, aunque las de mayor tamaño tienen más riesgo de requerir la colocación de una sonda de nefrostomía (p=0,013). Finalmente, la LEOC sobre litiasis localizadas en la unión uréterovesical tiene una eficacia superior que el resto, aunque no estadísticamente significativa. CONCLUSIONES: El tratamiento de la litiasis en el RT mediante LEOC tiene una eficacia del 87 por ciento. Los mejores resultados se obtienen en litiasis únicas localizadas en la unión uréterovesical (AU)
Subject(s)
Middle Aged , Male , Female , Humans , Kidney Transplantation , Lithotripsy , Urinary Calculi , Postoperative Complications , Prognosis , Follow-Up StudiesABSTRACT
OBJETIVO: Presentar un caso de absceso prostático que precisó tratamiento quirúrgico de urgencias por su evolución agresiva. METODOS: Descripción del caso de un paciente varón de 61 años, diagnosticado de urgencias de absceso prostático procediendo inicialmente a tratamiento conservador mediante antibioticoterapia y derivación urinaria. Pero dado su deterioro clínico hacia la sepsis y la repercusión del tramo urinario superior se decide intervenirlo quirúrgicamente mediante drenaje perineal. RESULTADOS: El cuadro séptico se resolvió inmediatamente, presentando en el postoperatorio inmediato una fístula prostatoperineal que se resuelve prolongando la derivación urinaria mediante cistostomía. Dada la evolución tórpida del cuadro se solicita serología siendo positiva a VIH. CONCLUSIONES: Destacamos este caso por la gran agresividad que presentó debido posiblemente a la existencia de factores favorecedores como son la diabetes y la inmunosupresión (VIH).Dada la gran variedad de presentación de este cuadro hay que tener una alto grado de sospecha para su diagnóstico y una vez realizado se recomienda un tratamiento inmediato. Realizamos una revisión de factores etiopatogénicos, hallazgos clínicos, diagnóstico y posibilidades terapéuticas (AU)
No disponible
Subject(s)
Male , Female , Humans , Prostatic Diseases , Pseudomonas Infections , Abscess , Emergency TreatmentABSTRACT
A comparative study was performed on the venoms of adult specimens of the neotropical rattlesnake, Crotalus durissus, from Guatemala, Costa Rica, Venezuela and Brazil, together with the venom of newborn specimens of C. d. durissus from Costa Rica. Venoms from Brazil (C. d. terrificus) and from newborn specimens of C. d. durissus presented an electrophoretic pattern characterized by the predominance of bands with molecular mass of 36 and 15 kDa, whereas those of adult specimens of C. d. durissus from Guatemala and Costa Rica, and C. d. cumanensis from Venezuela, showed a conspicuous band of 62 kDa, and additional bands of 36, 29 and 15 kDa. Moreover, venoms from C. d. terrificus and C. d. cumanensis showed a prominent band of < 10 kDa that probably corresponds to crotamine, since a 'crotamine-like' activity was detected in these venoms upon intraperitoneal injection in mice. Venoms of C. d. terrificus, C. d cumanensis and newborn C. d. durissus induced higher lethal and myotoxic effects than those of adult C. d. durissus. In contrast, adult C. d. durissus and C. d. cumanensis venoms induced hemorrhage, whereas venoms of C. d. terrificus and newborn C. d. durissus lacked this effect. All venoms showed coagulant effect in plasma, the highest activity being observed in the venom of newborn C. d. durissus. An anti-crotalic antivenom produced by Instituto Butantan (Brazil), using C. d. terrificus venom as antigen, was effective in the neutralization of lethal, myotoxic and coagulant effects of all venoms studied, being ineffective in the neutralization of hemorrhagic activity of the venoms of C. d. cumanensis and C. d. durissus. On the other hand, a polyvalent antivenom produced by Instituto Clodomiro Picado (Costa Rica), using the venoms of C. d. durissus. Bothrops asper and Lachesis stenophrys as antigens, was able to neutralize lethal, myotoxic, coagulant and hemorrhagic effects of C. d. durissus venom, but was ineffective in the neutralization of lethality and myotoxicity of C. d. terrificus, C. d. cumanensis and newborn C. d. durissus venom. The high toxicity of South American and newborn C. d. durissus venoms is related to the presence of high concentrations of the neurotoxic phospholipase A2 complex 'crotoxin'. Accordingly, antivenom from Instituto Butantan has a much higher titer of anti-crotoxin antibodies than antivenom from Instituto Clodomiro Picado. Crotalus durissus represents an example of intraspecies variation in venom composition and pharmacology that has relevant pathophysiologic and therapeutic implications.
Subject(s)
Crotalid Venoms/classification , Crotalus , Animals , Brazil , Costa Rica , Crotalid Venoms/pharmacology , Electrophoresis, Polyacrylamide Gel , Guatemala , Mice , VenezuelaABSTRACT
A comparative study was performed on the venoms of adult specimens of the neotropical rattlesnake, Crotalus durissus, from Guatemala, Costa Rica, Venezuela and Brazil, together with the venom of newborn specimens of C. d. durissus from Costa Rica. Venoms from Brazil (C. d. terrificus) and from newborn specimens of C. d. durissus presented an electrophoretic pattern characterized by the predominance of bands with molecular mass of 36 and 15 kDa, whereas those of adult specimens of C. d. durissus from Guatemala and Costa Rica, and C. d. cumanensis from Venezuela, showed a conspicuous band of 62 kDa, and additional bands of 36, 29 and 15 kDa. Moreover, venoms from C. d. terrificus and C. d. cumanensis showed a prominent band of < 10 kDa that probably corresponds to crotamine, since a 'crotamine-like' activity was detected in these venoms upon intraperitoneal injection in mice. Venoms of C. d. terrificus, C. d cumanensis and newborn C. d. durissus induced higher lethal and myotoxic effects than those of adult C. d. durissus. In contrast, adult C. d. durissus and C. d. cumanensis venoms induced hemorrhage, whereas venoms of C. d. terrificus and newborn C. d. durissus lacked this effect. All venoms showed coagulant effect in plasma, the highest activity being observed in the venom of newborn C. d. durissus. An anti-crotalic antivenom produced by Instituto Butantan (Brazil), using C. d. terrificus venom as antigen, was effective in the neutralization of lethal, myotoxic and coagulant effects of all venoms studied, being ineffective in the neutralization of hemorrhagic activity of the venoms of C. d. cumanensis and C. d. durissus. On the other hand, a polyvalent antivenom produced by Instituto Clodomiro Picado (Costa Rica), using the venoms of C. d. durissus. Bothrops asper and Lachesis stenophrys as antigens, was able to neutralize lethal, myotoxic, coagulant and hemorrhagic effects of C. d. durissus venom, but was ineffective in the neutralization of lethality and myotoxicity of C. d. terrificus, C. d. cumanensis and newborn C. d. durissus venom. The high toxicity of South American and newborn C. d. durissus venoms is related to the presence of high concentrations of the neurotoxic phospholipase A2 complex 'crotoxin'. Accordingly, antivenom from Instituto Butantan has a much higher titer of anti-crotoxin antibodies than antivenom from Instituto Clodomiro Picado. Crotalus durissus represents an example of intraspecies variation in venom composition and pharm
Subject(s)
Animals , Mice , Crotalus , Crotalid Venoms/classification , Brazil , Costa Rica , Electrophoresis, Polyacrylamide Gel , Guatemala , Crotalid Venoms/pharmacology , VenezuelaABSTRACT
La capacidad de formar biopelículas y la presencia de receptores Fc reprecentan dos de los factores de virulencia facilmente identificables en las cepas de Staphylococcus. El primero además de facilitar la colonización de superficies, puede incorporar proteínas de hospedero, lo que traduce en mimetismo ante el sistema inmune, lo cual es magnificado por la presencia de receptores Fc que incorporan inmunoglobulinas a la superficie de la bacteria. Ambos factores de virulencia se evaluaron en 57 cepas de Staphylococcus (29 S. aureus y 28 S. epidermidis) aisladas de casos clínicos y en 64 cepas de S. epidermidis aisladas de individuos sanos. La biopelícula se evidenció mediante tinción con safranina del tubo de cultivo y los receptores Fc mediante hemaglutinación de eritrocitos del grupo A sensibilizando previamente las bacterias con suero anti grupo sanguíneo A. Los receptores Fc se identificaron en el 79 por ciento de las cepas de S. aureus y en el 89 por ciento de S epidermidis aisladas de casos clínicos y solo en el 41 por ciento de las aisladas de individuos sanos. La producción de biopelículas se evidenció en el 45 por ciento y el 32 por ciento de S. aureus y S epidermidis respectivamente aisladas de casos clínicos, y en el 74 por ciento de las cepas aisladas de individuos sanos. La gran proporción de individuos sanos con cepas con potencialidad para colonizar superficies internas, llama la atención en la necesidad de extremar las medidas de asepcia en procesos de venipunción y en la implantación de catéteres. (Rev Cost Cien Med 2000; 21(1-2): 51-6) Palabras clave: Staphylococcus aureus, S. epidermidis, biopelícula, receptores Fc
