Higher-order interactions induce anomalous transitions to synchrony.

We analyze the simplest model of identical coupled phase oscillators subject to two-body and three-body interactions with permutation symmetry and phase lags. This model is derived from an ensemble of weakly coupled nonlinear oscillators by phase reduction, where the first and second harmonic interactions with phase lags naturally appear. Our study indicates that the higher-order interactions induce anomalous transitions to synchrony. Unlike the conventional Kuramoto model, higher-order interactions lead to anomalous phenomena such as multistability of full synchronization, incoherent, and two-cluster states, and transitions to synchrony through slow switching and clustering. Phase diagrams of the dynamical regimes are constructed theoretically and verified by direct numerical simulations. We also show that similar transition scenarios are observed even if a small heterogeneity in the oscillators' frequency is included.

Prevalence and Prognosis of Hypothyroidism in Patients With Chronic Thromboembolic Pulmonary Hypertension: An Updated Review With Description of Case Series.

Hypothyroidism has been shown to have several effects on organs, including derangements in the coagulation system, impairing endothelial function, but data on the importance of hypothyroidism in the pathogenesis and development of chronic thromboembolic pulmonary hypertension (CTEPH) are limited. This report presents an updated review of the prevalence and prognosis of hypothyroidism in patients diagnosed with CTEPH, including a detailed retrospective description of the series. The descriptive case series included 34 adult patients diagnosed with CTEPH, of whom 11 patients were diagnosed with hypothyroidism. The prevalence of hypothyroidism in CTEPH was found to be 32.35%. All patients with hypothyroidism had NYHA functional Class II-III. Hemodynamic values obtained through right heart catheterization (RHC) showed that patients with hypothyroidism had significantly higher mean pulmonary arterial pressures (mPAP), with a mean of 56.91 mm Hg vs 43.93 mm Hg (p = 0.026), and the PVR in dynes/sec/cm5 was 932 vs 541 (p = 0.027). Significant differences in PVR were found in wood units (WU) 11.91 vs 7.11 (p = 0.042). The mean level of brain natriuretic peptide (BNP) between both groups was 797.3 pg/mL for patients with hypothyroidism vs 262.02 pg/mL in patients with euthyroidism (p = .032). Hypothyroidism may significantly affect patients' clinical and hemodynamic outcomes in patients with CTEPH. Hypothyroidism as a risk factor in the evaluation and treatment of these patients is vital to optimize outcomes in CTEPH; further research is warranted whether hypothyroidism therapies could alter such outcomes.

Efficient moment-based approach to the simulation of infinitely many heterogeneous phase oscillators.

The dynamics of ensembles of phase oscillators are usually described considering their infinite-size limit. In practice, however, this limit is fully accessible only if the Ott-Antonsen theory can be applied, and the heterogeneity is distributed following a rational function. In this work, we demonstrate the usefulness of a moment-based scheme to reproduce the dynamics of infinitely many oscillators. Our analysis is particularized for Gaussian heterogeneities, leading to a Fourier-Hermite decomposition of the oscillator density. The Fourier-Hermite moments obey a set of hierarchical ordinary differential equations. As a preliminary experiment, the effects of truncating the moment system and implementing different closures are tested in the analytically solvable Kuramoto model. The moment-based approach proves to be much more efficient than the direct simulation of a large oscillator ensemble. The convenience of the moment-based approach is exploited in two illustrative examples: (i) the Kuramoto model with bimodal frequency distribution, and (ii) the "enlarged Kuramoto model" (endowed with nonpairwise interactions). In both systems, we obtain new results inaccessible through direct numerical integration of populations.

Enlarged Kuramoto model: Secondary instability and transition to collective chaos.

The emergence of collective synchrony from an incoherent state is a phenomenon essentially described by the Kuramoto model. This canonical model was derived perturbatively, by applying phase reduction to an ensemble of heterogeneous, globally coupled Stuart-Landau oscillators. This derivation neglects nonlinearities in the coupling constant. We show here that a comprehensive analysis requires extending the Kuramoto model up to quadratic order. This "enlarged Kuramoto model" comprises three-body (nonpairwise) interactions, which induce strikingly complex phenomenology at certain parameter values. As the coupling is increased, a secondary instability renders the synchronized state unstable, and subsequent bifurcations lead to collective chaos. An efficient numerical study of the thermodynamic limit, valid for Gaussian heterogeneity, is carried out by means of a Fourier-Hermite decomposition of the oscillator density.

An easy spectrophotometric acid-base titration protocol for dissolved organic matter.

UV-vis spectrophotometric acid-base titration can characterize dissolved organic matter (DOM) acid-base properties. However, it requires incremental pH adjustment, which make the procedure time consuming and the results subjected to dilution effect. This study brings forth a new approach, referred as the "buffer method" for pH adjustments, by using carefully selected pH-buffers to adjust the pH. This, statistically validated method minimizes the pH adjustment time and lightens the laboratory work load. Chemical product cost associated with this novel method is slightly increased as compared to the previous approach, due to the necessity to use pH-buffers. • Buffer method: Acid-base titration by using buffer for pH adjustment • Buffer method validated by statistical means • Rapid, reliable and economical method.

Dogs Detecting COVID-19 From Sweat and Saliva of Positive People: A Field Experience in Mexico.

Context: Molecular tests are useful in detecting COVID-19, but they are expensive in developing countries. COVID-19-sniffing dogs are an alternative due to their reported sensitivity (>80%) and specificity (>90%). However, most of the published evidence is experimental, and there is a need to determine the performance of the dogs in field conditions. Hence, we aimed to test the sensitivity and specificity of COVID-19-sniffing dogs in the field. Methods: We trained four dogs with sweat and three dogs with saliva of COVID-19-positive patients, respectively, for 4.5 months. The samples were obtained from a health center in Hermosillo, Sonora, with the restriction to spend 5 min per patient. We calculated sensitivity, specificity, and their 95% confidence intervals (CI). Results: Two sweat-sniffing dogs reached 76 and 80% sensitivity, with the 95% CI not overlapping the random value of 50%, and 75 and 88% specificity, with the 95% CI not overlapping the 50% value. The 95% CI of the sensitivity and specificity of the other two sweat dogs overlapped the 50% value. Two saliva-sniffing dogs had 70 and 78% sensitivity, and the 95% CI of their sensitivity and specificity did not overlap the 50% value. The 95% CI of the third dog's sensitivity and specificity overlapped the 50% value. Conclusion: Four of the six dogs were able to detect positive samples of patients with COVID-19, with sensitivity and specificity values significantly different from random in the field. We considered the performance of the dogs promising because it is reasonable to expect that with gauze exposed for a longer time to sweat and saliva of people with COVID-19, their detection capacity would improve. The target is to reach the sensitivity range requested by the World Health Organization for the performance of an antigen test (≥80% sensitivity, ≥97% specificity). If so, dogs could become important allies for the control of the COVID-19 pandemic, especially in developing countries.

Evaluation of nutritional composition and technological functionality of whole American Bullfrog (Lithobates catesbeianus), its skin, and its legs as potential food ingredients.

Frog farming systems do not take advantage of their byproducts, which represents health risks and environmental pollution. The present study aimed to evaluate the proximate composition, amino acid, and fatty acid profile of American Bullfrog byproducts (whole frogs (WF), legs (LF), and skin (SF)) and their technological functionality. Results showed that WF, LF, and SF protein content was 47.6, 88.4, and 91.1% dry base (d.b.), correspondingly. Fat content resulted in 34.6, 3.2, and 4.2% (d.b.), respectively. Moreover, byproducts contain all the essential amino acids (23.8-46.6%), and the unsaturated fatty acids predominated the saturated fats. Samples showed water and oil absorption capacities of 1.8-2.6% and 1.8-4.0%, respectively, while oil and water emulsion capacities were 76.7-98.3% and 36.1-85.6%, correspondingly. Additionally, SF presented a gelling capacity in a 5% concentration. These results showed that frogs' byproducts have adequate nutritional and functional capacities, compared to other vegetable and animal flours used in the industry.

Presentaciones atípicas de COVID-19: Serie de casos / COVID-19 atypical presentations: Case series

Resumen El objetivo del presente trabajo fue presentar una serie de casos de COVID-19 con manifestaciones atípicas de la enfermedad. Los casos fueron atendidos por un equipo interdisciplinario de personal de la salud de una clínica de cuarto nivel en Barranquilla, Colombia, y posteriormente los investigadores tomaron los datos de las historias clínicas. Se evaluaron tres casos: el primero tuvo evolución tórpida y coinfección con virus de la influenza H1N1 y los otros dos, manifestaciones gastrointestinales como debut de la enfermedad; todos tuvieron desenlace satisfactorio. La pandemia por SARS-CoV-2 cada día cobra más vidas, por lo que para identificar oportunamente a los infectados y tomar medidas tanto terapéuticas como de prevención y así evitar la propagación de la enfermedad y lograr su control, es necesario realizar reportes de caso en donde se evidencie la diversa variedad de presentaciones de COVID-19.

Abstract The objective of this work is to present a series of cases of COVID-19 with atypical manifestations of the disease. The cases were evaluated by an interdisciplinary team of health personnel from a fourth-level clinic in Barranquilla, Colombia, and the data was subsequently taken from the clinical history of each patient. Three cases were evaluated, initially the first case with torpid evolution, coinfection with H1N1 influenza virus, however, with satisfactory outcome, and cases two and three with gastrointestinal manifestations as disease debut, with satisfactory evolution. The SARS-CoV-2 pandemic takes more lives every day, so it is necessary to describe the cases and their diverse variety of presentation, to identify the infected and take both therapeutic and preventive measures. To prevent the spread of the disease and achieve its control.

Quasi phase reduction of all-to-all strongly coupled λ-ω oscillators near incoherent states.

The dynamics of an ensemble of N weakly coupled limit-cycle oscillators can be captured by their N phases using standard phase reduction techniques. However, it is a phenomenological fact that all-to-all strongly coupled limit-cycle oscillators may behave as "quasiphase oscillators," evidencing the need of novel reduction strategies. We introduce, here, quasi phase reduction (QPR), a scheme suited for identical oscillators with polar symmetry (λ-ω systems). By applying QPR, we achieve a reduction to N+2 degrees of freedom: N phase oscillators interacting through one independent complex variable. This "quasi phase model" is asymptotically valid in the neighborhood of incoherent states, irrespective of the coupling strength. The effectiveness of QPR is illustrated in a particular case, an ensemble of Stuart-Landau oscillators, obtaining exact stability boundaries of uniform and nonuniform incoherent states for a variety of couplings. An extension of QPR beyond the neighborhood of incoherence is also explored. Finally, a general QPR model with N+2M degrees of freedom is obtained for coupling through the first M harmonics.

Neochloris oleoabundans Growth Evaluation Under Different Nitrogen:Phosphorus:Carbon Feeding Strategies.

Microalgae are photosynthetic microorganisms known for their variety of compounds that can be useful for food, feed, pharmaceuticals, and fuel industries. Microalgae production costs have been one of the major obstacles to large-scale commercial production. Therefore, several studies are still being performed aiming to increase biomass by developing novel photobioreactor design and microalgae cultivation techniques. This work's purpose is to increase Neochloris oleoabundans biomass. Different nutrient-feeding regimes were tested in N. oleoabundans cultivation in Erlenmeyer flasks and bench-scale tubular photobioreactor. In Erlenmeyer flasks, the best concentrations of nitrate and phosphate were 8.82 mM and 5.16 mM, respectively. In bench-scale tubular photobioreactor, NaNO3 proved to be the best nitrogen source, in comparison with (NH4)2SO4 and NH4NO3. Still in the photobioreator, the addition of nitrate by fed-batch process combined with automated system of CO2 feeding showed to be of utmost importance for insuring a high density of N. oleoabundans. The essential nutrients evaluated in this work play an important role on N. oleoabundans biomass accumulation, as well as the photobioreactor configuration and feeding regimes.

Antioxidant Content of Frozen, Convective Air-Dried, Freeze-Dried, and Swell-Dried Chokecherries (Prunus virginiana L.).

Chokecherry (Prunus virginiana L.) is rich in bioactive molecules as phenolics, which can act as antioxidants, anti-inflammatory, anticancer, among others; however, due to its high perishability, most of this fruit is wasted. Freezing and sun drying have been the most adopted techniques to avoid its postharvest deterioration. Nevertheless, both processes have presented some drawbacks as high storage costs and losses of bioactive molecules. Therefore, to preserve these molecules, this study compared the impact of convective airflow drying (CAD), freezing (FR), freeze drying (FD), and swell drying (SD). Total phenolics content (TPC), total flavonoids content (TFC), kuromanin concentration (KC), and antioxidant activity (antiradical activity (ARA) and Trolox equivalent antioxidant capacity assay (TEAC)) of chokecherries were measured. "Swell drying" is a drying process coupling convective airflow drying to the Instant Controlled Pressure Drop (DIC) expansion. A central composite rotatable design was applied to optimize the DIC variables and responses. Results showed that both freezing and swell drying effectively preserve the TPC, TFC, KC, and ARA. Moreover, SD samples also presented the highest TEAC. Contrary, in the case of CAD, it caused the highest losses of both antioxidant content and activity. Swell drying remedies the shrinkage and collapsing of dried food structure, which results in a better antioxidants extraction.

Evaluación y manejo del riesgo cardiovascular en infección por VIH. Consenso de expertos ACIN / Evaluation and management of cardiovascualr risk in VIH infection: Expert consensus of ACIN (Colombian Association of Infectious Diseases)

Los pacientes con infección por VIH tienen una mayor incidencia de eventos cardiovasculares en comparación con la población general; los factores que contribuyen al incremento del riesgo de eventos cardiovasculares son la prevalencia de factores de riesgo cardiovascular tradicionales (FRCV), la infección por VIH que condiciona tanto un proceso de inflamación crónica como alteración de la función endotelial y la exposición a los antirretrovirales. Los factores que deben ser objeto de intervención son los FRCV tradicionales, en especial la alta tasa de fumadores entre este grupo de pacientes, la tamización y tratamiento de HTA, el síndrome metabólico y el acceso temprano a la terapia antirretroviral con medicamentos con mayor perfil de seguridad . Esta guía pretende proveer información y recomendaciones en el ámbito nacional acerca de la relación entre la infección por VIH/SIDA (Síndrome de Inmunodeficiencia Adquirida), uso de antirretrovirales y riesgo cardiovascular.

Patients with VIH infection have greater risk for cardiovascular diseases compared to general population. Risk factors that increase the frequency of cardiovascular events are: presence of cardiovascular traditional risk factors, chronic inflammation by HIV that impairs endothelial function and the exposure to antiretrovirals. The factors that should be the target for intervention are the traditional know cardiovascular factors such, especially high rate of smokers, screening and treatment for hypertension, metabolic syndrome and early access to HAART. The present guidelines provides information about the use of antiretrovirals in patients with HIV and its relation with cardiovascular risk.

Phase reduction beyond the first order: The case of the mean-field complex Ginzburg-Landau equation.

Phase reduction is a powerful technique that makes possible to describe the dynamics of a weakly perturbed limit-cycle oscillator in terms of its phase. For ensembles of oscillators, a classical example of phase reduction is the derivation of the Kuramoto model from the mean-field complex Ginzburg-Landau equation (MF-CGLE). Still, the Kuramoto model is a first-order phase approximation that displays either full synchronization or incoherence, but none of the nontrivial dynamics of the MF-CGLE. This fact calls for an expansion beyond the first order in the coupling constant. We develop an isochron-based scheme to obtain the second-order phase approximation, which reproduces the weak-coupling dynamics of the MF-CGLE. The practicality of our method is evidenced by extending the calculation up to third order. Each new term of the power-series expansion contributes with additional higher-order multibody (i.e., nonpairwise) interactions. This points to intricate multibody phase interactions as the source of pure collective chaos in the MF-CGLE at moderate coupling.

Impacto sobre la resistencia bacteriana de la revisión previa de la prescripción de antibióticos por el servicio farmacéutico en hospitales del Atlántico(Colombia) / Impact on the bacterial resistance of the previous revision of the prescription of antibiotics by the pharmaceutical service in hospitals of Atlántico (Colombia)

RESUMEN Objetivo: Determinar el impacto sobre la resistencia bacteriana de la revisión previa de la prescripción de antibióticos por parte del servicio farmacéutico en hospitales de mediana y alta complejidad del departamento del Atlántico (Colombia). Metodología: Se analizaron los valores de resistencia de bacterias Gram positivas, Enterobacterias y Gram negativos no fermentadores reportados en cinco institutos prestadores de salud (IPS) del departamento del Atlántico, en dos periodos (preintervención e intervención), de 12 meses cada uno, entre junio de 2015 y mayo de 2017. Resultados: Durante los dos periodos de estudio se identificaron 68 microorganismos en 8590 aislamientos microbiológicos provenientes de muestras de orina (40,3 %), sangre (21,7 %), tejidos (8,5 %) y otras (29,5 %). Los microorganismos aislados más frecuentemente fueron Escherichia coli (28,9 %), Staphylococcus coagulasa negativo (12,1%), Klebsiella pneumoniae (12,0 %), Pseudomonas aeruginosa (11,1 %) y Staphylococcus aureus (7,2 %). Durante los dos periodos la resistencia global osciló entre 27 y 40 %. Durante la Preintervención la resistencia osciló entre el 33 y el 39 %, mientras que durante la Intervención estuvo entre el 27 y 40 %. Al comparar los periodos de estudio solo hubo disminución significativa de la resistencia en los primeros nueve meses del periodo de intervención (p < 0.05). Conclusiones: Los valores de resistencia bacteriana reportados en el periodo de intervención fueron menores que en el periodo de preintervención. Se evidenció que la revisión previa de la prescripción por parte del servicio farmacéutico en las instituciones participantes influye en una disminución significativa de la resistencia bacteriana, pero que esta debe ser tanto continua como incremental.

ABSTRACT Objective: To determine the impact on bacterial resistance of the previous review of the prescription of antibiotics by the pharmaceutical service in medium and high complexity hospitals of the Department of Atlántico (Colombia). Methodology: Resistance values were analyzed for Gram-positive bacteria, Enterobacte-rial and non-fermenting Gram-negative bacteria reported in five health care institutions (IPS) of the Atlántico Department, in two periods (pre-intervention and intervention), of 12 months each between the months of June 2015 and May 2017. Results: During the two study periods, 68 microorganisms were identified in 8,590 microbiological isolates from urine samples (40.3 %), blood samples (21.7 %), tissues (8.5%) and others (29.5 %). The most frequently isolated microorganisms were Escherichia coli (28.9 %), Coagulase Negative Staphylococcus (12.1 %), Klebsiella pneumoniae (12.0 %), Pseudomonas aeruginosa (11.1 %) and S. aureus (7.2 %). During both periods the global resistance ranged between 27 and 40 %. During the Pre-intervention the resistance ranged between 33 and 39 %, while during the Intervention it was between 27 and 40 %. When comparing study periods, there was only significant decrease in resistance in the first nine months of the intervention period (p <0.05). Conclusions: the bacterial resistance values reported during the intervention period were lower than in the pre-intervention period. It was evidenced that the previous revision of the prescription by the pharmaceutical service in the participating institutions influences a significant decrease of the bacterial resistance; but that this must be both continuous and incremental.

Estudo da produção de biomassa e lipídios no cultivo de Neochloris oleoabundans sob diferentes condições de estresse nutricional e físico / Investigation on biomass and lipids accumulation in Neochloris oleoabundans cultivation under different nutritional and phisical stress conditions

As microalgas são candidatas promissoras para a produção em larga escala de biocombustíveis devido a sua alta eficiência fotossintética. No entanto, os custos relativamente altos de produção por baixas produtividades em lipídios têm sido um dos principais obstáculos que impedem sua produção comercial. Portanto, é necessário focar a pesquisa no aumento da biomassa e na produtividade em lipídios, através do desenvolvimento de biorreatores e técnicas de cultivo inovadoras. Numa primeira fase, este estudo mostra a otimização dos regimes de adição de nutrientes no cultivo de Neochloris oleoabundans em fotobiorreatores tubulares, determinando que a melhor metodologia de adição de CO2 é adicionando-o de forma intermitente e automatizada, enquanto que o melhor processo de alimentação de nitrogênio é por meio de um processo em batelada alimentada tomando como uma referência a produtividade diária de biomassa. Na segunda etapa, foi testada a influência de agentes estressores adicionados ao cultivo sob carência de nitrogênio, tais como tiossulfato de sódio como agente redutor e cloreto de sódio e glicerina como agentes de choque osmótico, buscando um acúmulo de lipídios na biomassa. Os resultados mostraram que o tiossulfato de sódio em 1,2 mM e o cloreto de sódio em 2,2 mM aumentaram o total de lipídios em 21% e 25%, respectivamente. Finalmente, foram testados diferentes regimes de luz, com um esquema 12:12, sendo 12 horas de luz fluorescente e 12 horas com um sistema distinto: escuro, diodos emissores de luz (LED) vermelha e LED branca. Os melhores resultados foram obtidos com LED branca, com um acúmulo de lipídios de até 27% da biomassa seca e uma concentração final de células de 2335mg/L, estabelecendo assim um método de iluminação econômica com alta produtividade (145mg / L dia)

Microalgae are promising candidates for large-scale global biofuel production because of their high photosynthetic efficiency. However, relatively high production costs due to low lipid productivity have been one of the major obstacles impeding their commercial production. Therefore, it is necessary to accurate the research into an increase in biomass and oil productivity, by means of novel bioreactors' design and cultivation techniques. On a first stage, this study shows the optimization of nutrients' addition regimes in Neochloris oleoabundans cultivation in tubular photobioreactors, finding that the best CO2 addition methodology is an automatized intermittent adding and the best feeding process for nitrogen is a fed-batch process taking as a reference the daily biomass productivity. On the second step, it was tested the influence of stressing agents added to the culture under nitrogen starvation, such as sodium thiosulphate for reducing environment and sodium chloride and glycerol for osmotic shock, aiming lipid accumulation in the biomass. The results showed that sodium thiosulphate at 1,2mM and sodium chloride at 2,2mM raised the total lipids up to 21% and 25% respectively. Finally, there were tested different light regimes, with a scheme 12:12, being 12 hours of fluorescent light and 12 hours of a singular system: dark, red light-emitting-diodes (LED) and white LED. The best results were obtained with white LED, with an accumulation up to 27% of dry biomass and a final cell concentration up to 2335mg/L, establishing an economic illumination method with high productivity

Riesgo cardiovascular y síndrome metabólico en pacientes VIH positivos en el Caribe colombiano / Cardiovascular risk and metabolic syndrome in HIV-positive patients in the colombian caribbean

Objetivo: estimar el riesgo cardiovascular y la prevalencia de síndrome metabólico de un grupo de pacientes VIH positivos de la región caribe colombiana. Métodos: se llevó a cabo un estudio descriptivo de un grupo de 90 pacientes de ambos géneros, VIH positivos que asisten al programa de control de la EPS SURA. Se estimó la frecuencia síndrome metabólico, riesgo cardiovascular y el tipo de esquema de tratamiento. Resultados: 72,2% son hombres con edad media de 39.7 años (IC95%: 37.3-42.1) la edad promedio general fue de 40.9 años (IC95%: 38.7-43.0). El 5.4% eran diabéticos y 14.1% fueron hipertensos. El 87.8% recibía algún esquema de tratamiento. La frecuencia de síndrome metabólico fue 46% en pacientes en tratamiento con inhibidores de proteasa frente a un 36% en los que no usan tratamiento. Casi la mitad del grupo tenía un índice de masa corporal (IMC) en sobrepeso y obesidad (36 y 13% respectivamente). Conclusiones: se detectó un porcentaje alto de insulinorresistencia (36%) en nuestros pacientes VIH positivos. Se requieren medidas eficaces para prevenir el curso natural de esta entidad. (ActaMed Colomb 2013; 38: 222-227).

Objective: to estimate cardiovascular risk and the prevalence of metabolic syndrome in a group of HIV-positive patients in the Colombian Caribbean region. Methods: we conducted a descriptive study of a group of 90 patients of both genders HIV positive seen in the control program of EPS SURA . Frequency of metabolic syndrome, cardiovascular risk and type of treatment schedule, were estimated. Results: 72.2% were male with an average age of 39.7 years (95% CI: 37.3-42.1) overall average age was 40.9 years (95% CI: 38.7-43.0). 5.4% had diabetes and 14.1% were hypertensive. 87.8% received a treatment regimen. The frequency of metabolic syndrome was 46% in patients treated with protease inhibitors compared to 36% in those not being treated. Almost half of the group had a body mass index (BMI) in overweight and obesesity (36 and 13% respectively). Conclusions: we found a high percentage of insulin resistance (36%) in our HIV positive patients. Effective measures are required to prevent the natural course of this entity. (Acta Med Colomb 2013;38: 222-227).

Laparoscopic ultrasound-guided radiofrequency volumetric thermal ablation of symptomatic uterine leiomyomas: feasibility study using the Halt 2000 Ablation System.

Thirty-one women aged 28 to 51 years with symptomatic uterine leiomyomas who desired uterine preservation underwent outpatient laparoscopic, ultrasound-guided, radiofrequency volumetric thermal ablation using the Halt 2000 System. Postoperative follow-up occurred at 3, 6, and 12 months. The primary outcome measures were patient safety, frequency of adverse events, repeat intervention rate because of symptoms of myoma, symptom severity, and health-related quality-of-life scores from the validated Uterine Fibroid Symptom and Quality-of-Life Questionnaire. Secondary outcome measures were uterine volume changes over time. At 3, 6, and 12 months, respectively, mean symptom severity scores improved significantly compared with baseline, by 59.7% (95% confidence interval [CI], 44.8-74.7], 71.7% [95% CI, 55.7%-87.7%], and 82.0% (95% CI, 70.9%-93.1%). The increase in mean health-related quality-of-life scores over time reached statistical significance (p <.001): 60.15 (95% CI, 51.6%-68.7%) at baseline, 87.9 (95% CI, 82.1%-93.7%) at 3 months, 90.8 (95% CI, 82.1%-99.5%) at 6 months, and 97.8 (95% CI, 96.2-99.4) at 12 months. Mean (SD) uterine volume decreased from 194.4 (105.9 cm(3)) at baseline to 159.5 (66.8) at 3 months, 147.2 (73.0 cm(3)) at 6 months, and 113.2 (53.5 cm(3)) at 12 months (p = .006). There were no procedure-related repeat hospitalizations, repeat treatments, or any procedures related to symptoms of myoma after radiofrequency ablation. An anterior abdominal wall vascular injury was discovered in the early postoperative period and resolved after vessel ligation. Volumetric thermal ablation using the Halt 2000 System produced significant reduction in symptoms and improvement in quality of life at 1 year after treatment, with an excellent safety profile. Additional larger multicenter studies are needed to confirm these results.

Cirugía mínimamente invasiva para el cierre de la comunicación interauricular en niños / Closure interatrial communication with minimally invasive surgical procedure in children

Objetivos. El cierre de la Comunicación Interauricular (CIA) a través de diferentes técnicas quirúrgicas mínimamente invasivas viene suscitando interés en los últimos años. Presentamos nuestra experiencia utilizando la miniesternotomía para el cierre de la CIA en niños. Material y Método. Diecinueve pacientes, con edades entre 8 meses y 9 años, fueron sometidos a cierre quirúrgico electivo de CIA. Fue realizada esternotomía parcial desde la apófisis xifoides hasta dos espacios intercostales en sentido cefálico (incisión media de 6 centímetros). La preparación para circulación extracorpórea (CEC) fue íntegramente realizada a través de esta incisión. Utilizamos una única dosis de cardioplegia sanguínea fría. En 7 casos se suturó directamente el defecto y en 12 utilizamos parche de pericardio autólogo. Ningún instrumento quirúrgico especial fue necesario. Resultados. No ocurrieron muertes hospitalares ni tardías; no hubo necesidad de conversión a esternotomía total, ni cambio del local de canulación. Los tiempos de CECe isquemia fueron equivalentes a los empleados a través de esternotomía convencional, así como la permanencia hospitalar. Todos los pacientes fueron extubados precozmente. Complicaciones mayores estuvieron ausentes. No hubo ningún caso de inestabilidad esternal, ni infección de herida operatoria. Conclusiones. El cierre de la CIA en niños puede realizarse a través de la técnica de miniesternotomía; es un procedimiento seguro, no requiere de aparatos especiales, es reproducible en la mayoría de niños y favorece una rápida recuperación de estos pacientescon un resultado estético satisfactorio.

Objectives. The closure of the Atrial Septal Defect (ASD), through different minimally invasive techniques have been arrousing interest in the past few years. In this paper we are presenting our experience using a ministernotomy to close ASD in children. Methods and Materials. Nineteen patients were electively operated to close an ASD, with ages varying between 8 months and 9 years. A partial sternotomy that began at the xyphoid process and extended to two subsequent intercostal spaces cefalad (mean incision extension of 6 cm). Preparation for bypass was all through this incisionin the conventional way. A single dose of cold blood cardioplegia was used. In 5 cases a direct suture of the defect was made and in other 5 an autologus pericardial patch was used. No other special material or instrument was used. Results. There were no in house nor late deaths; andnone of the cases needed conversion to full sternotomyor change of cannulation sites. Bypass and crossclamp times were equivalent to those with full sternotomy as wellas in house permanence. All patients were extubated inthr operating room. There were no major complications nor wound infections or sternal instability. Conclusions. ASD closure in children can be made through the mini sternotomy technique. ItÆs safe and reproducible in most infants and does not require specialor sophisticated equipment. Favours rapid healing with a satisfactory esthetic result.

Medtronic Freestyle valve for right ventricular reconstruction in pediatric Ross operations.

BACKGROUND: The use of homograft conduits to reconstruct right ventricle (RV) to pulmonary artery (PA) connections is an essential component of the Ross operation. Homograft availability and cost may be problematic when considering the Ross operation. We elected in January 1998 to utilize commercially available xenografts as an alternative to homografts for RV/PA reconstruction in the pediatric Ross operation. Our early results using the Medtronic Freestyle valve (Medtronic, Minneapolis, MN) for RV/PA reconstruction are presented. METHODS: We reviewed our database for all Ross operations performed on children since January 1998. A total of 16 patients were identified. Eleven children received a Medtronic Freestyle valve, 2 children received a homograft, and 3 children received another type of xenograft. Echocardiographic evaluation of all children who received the Medtronic Freestyle valve was performed at hospital discharge and at two subsequent outpatient evaluations. RESULTS: The median peak instantaneous pressure gradient across the xenograft was 16 +/- 9 mm Hg (immediately after surgery before hospital discharge); 22 +/- 20 mm Hg at 23 +/- 11 months (first postdischarge follow-up); and 27 +/- 20 mm Hg at 35 +/- 9 months (second postdischarge follow-up). Linear regression analysis revealed an increasing pressure gradient with time (R(2)-adjusted = 0.44, p < 0.0001). At the same three observation points, the xenograft annulus diameter decreased: 25 +/- 1.2 mm; 19 +/- 4.3 mm; and 20 +/- 1.8 mm. Linear regression analysis revealed a decreasing annulus diameter with time (R(2)-adjusted = 0.41, p < 0.0001). CONCLUSIONS: The Medtronic Freestyle valve provides a possible alternative to homografts for the reconstruction of the RV/PA connection in the pediatric Ross operation. Long-term follow-up is necessary to evaluate this xenograft as an alternative to the homograft.

Cirugía de Glenn en el departamento de cardiopediatría INCOR-EsSalud / Glenn's surgery in the department of cardiopediatric incor-EsSalud

Objetivo: En el presente estudio retrospectivo realizado en el INCOR tiene como objetivo principal analizar los factores determinantes en el resultado quirúrgico de la cirugía de Glenn. Material y Métodos: Entre enero de 1999 y diciembre de 2002 se intervinieron 37 niños con esta técnica quirúrgica en el INCOR-EsSalud, cuyas edades oscilaron entre 5 meses y catorce años, los pesos fueron desde 4.5 hasta 41 kilos, hubieron 25 hombres y 11 mujeres, procedentes 5 ciudades de altura, 23 de la región costa y tres de la selva. Resultados: La mortalidad fue 8.1 por ciento y se asoció un valor de la presión de la arteria pulmonar igual o superior a 30 mmHg a mayor morbimortalidad. De igual manera un peso menor de 7 kilos, edad menor de un año, anormalidades anatómicas cardiacas complejas y pacientes con antecedente de enfermedades respiratorias frecuentes tuvieron una mayor estancia en la UCI post quirúrgica, los pacientes con fisiopatología de bajo flujo pulmonar no condicionaron una variable clínica de importancia en la morbimortalidad. La tasa de supervivencia a tres años fue del 92 por ciento. Conclusiones: Este tipo de cirugía es una buena alternativa terapéutica para las cardiopatías congénitas de corazón univentricular. La presión de la arteria pulmonar, el peso, la edad, así como los antecedentes pre-quirúrgicos, son variables importantes relacionadas con la evolución de estos pacientes.