[Embolization of spontaneous portosystemic shunts as treatment for refractory hepatic encephalopathy]. / Embolización de colaterales portosistémicas espontáneas como tratamiento de la encefalopatía hepática refractaria.

BACKGROUND: Hepatic encephalopathy (HE) is a common complication of cirrhosis associated with a reduced survival. The presence of high-flux spontaneous porto-systemic shunts can induce HE even in patients with preserved liver function. AIM: To evaluate the effect of spontaneous porto-systemic shunt embolization (SPSE) over HE and its long-term evolution. MATERIAL AND METHODS: Retrospective analysis of 11 patients (91% males) with severe HE non-responsive to medical treatment in whom a SPSE was performed. The grade of HE (employing West Haven score), survival, MELD and Child-Pugh score, ammonia levels, degree of disability (employing the modified Rankin scale (mRs)) were evaluated before and at thirty days after procedure. RESULTS: The most common etiology found was non-alcoholic steatohepatitis (63.6%). A reduction of at least two score points of HE was observed in all patients after thirty days. There was a significant reduction on median (IQR) West Haven score from 3 (2-3) at baseline to 1 (0-1) after the procedure (p < 0.01). Twelve months survival was 63.6%. There was a decrease in median ammonia level from 106.5 (79-165) (ug/dL) to 56 (43-61) after SPSE (p = 0.006). The median mRS score before and after the procedure was 3 (3-5) and 1 (1-2.5), respectively (p < 0.01). CONCLUSIONS: According to our experience, SPSE is a feasible and effective alternative to improve HE and functionality of patients with refractory EH.

Hepatic encephalopathy in a liver transplant recipient with stable liver function.

Postshunt hepatic encephalopathy after liver transplantation (LT) is an infrequent condition and is commonly associated with portal occlusion or stenosis and the presence of a patent portosystemic shunt. Portal vein stenosis (PVS) or thrombosis (PVT) are uncommon complications after LT. The overall frequency of both complications is reported to be less than 3%. When PVS or PVT develop early after LT, the occlusion of the portal vein can have catastrophic consequences to the graft including acute liver failure and graft loss. Late PVT/PVS are asymptomatic in approximately 50% of the cases and mainly diagnosed by a routine ultrasound. Symptomatic postshunt hepatic encephalopathy (HE) is a very infrequent condition after LT that has been scarcely reported in the literature. We present here the case of a liver recipient with normal graft function who presented with hepatic encephalopathy 3 months after LT with stable liver function but a severe portal stenosis and the presence of a spontaneous portosystemic shunt whose successful endovascular treatment was followed by the complete resolution of the HE.

The evolution of loan volume and non-performing loans under COVID-19 innovations: The Colombian case.

Financial institutions' scale of total and non-performing loans are important figures signaling economic activity and its risk level. COVID-19 created an external shock with overarching effects on the global economy, impacting the credit activity and debtors' ability to repay their obligations. We study how Colombia's loans and non-performing loans market ratios could react to an external shock (absent of any relief measures) by developing a vector autoregressive model with exogenous variables (VARX) with the Central Bank intervention rate as an exogenous variable. We use impulse response functions to simulate the impact of the COVID-19 pandemic on the market of loans and default levels in Colombia. Our results show that the effects remain significant over long periods.

Comparative complete scheme and booster effectiveness of COVID-19 vaccines in preventing SARS-CoV-2 infections with SARS-CoV-2 Omicron (BA.1) and Delta (B.1.617.2) variants: A case-case study based on electronic health records.

Background: Information on vaccine effectiveness in a context of novel variants of concern (VOC) emergence is of key importance to inform public health policies. This study aimed to estimate a measure of comparative vaccine effectiveness between Omicron (BA.1) and Delta (B.1.617.2 and sub-lineages) VOC according to vaccination exposure (primary or booster). Methods: We developed a case-case study using data on RT-PCR SARS-CoV-2-positive cases notified in Portugal during Weeks 49-51, 2021. To obtain measure of comparative vaccine effectiveness, we compared the odds of vaccination in Omicron cases versus Delta using logistic regression adjusted for age group, sex, region, week of diagnosis, and laboratory of origin. Results: Higher odds of vaccination were observed in cases infected by Omicron VOC compared with Delta VOC cases for both complete primary vaccination (odds ratio [OR] = 2.1; 95% confidence interval [CI]: 1.8 to 2.4) and booster dose (OR = 5.2; 95% CI: 3.1 to 8.8), equivalent to reduction of vaccine effectiveness from 44.7% and 92.8%, observed against infection with Delta, to -6.0% (95% CI: 29.2% to 12.7%) and 62.7% (95% CI: 35.7% to 77.9%), observed against infection with Omicron, for complete primary vaccination and booster dose, respectively. Conclusion: Consistent reduction in vaccine-induced protection against infection with Omicron was observed. Complete primary vaccination may not be protective against SARS-CoV-2 infection in regions where Omicron variant is dominant.

[Diagnostic yield of CT pulmonary angiography and venography for thromboembolic disease]. / Evaluación prospectiva de la venografía mediante angioTC en el diagnóstico de enfermedad tromboembólica.

BACKGROUND: CT pulmonary angiography is the diagnostic procedure of choice for non-massive pulmonary embolism. AIM: To assess the diagnostic yield for thromboembolic disease of CT pulmonary angiography and venography using a 64-slice multidetector tomography. MATERIAL AND METHODS: Prospective study of patients with a clinical suspicion of thromboembolic disease, subjected to CT pulmonary angiography and venography. The presence and location of pulmonary thromboembolism, of isolated or concomitant deep venous thrombosis and of other significant radiological findings, were registered. RESULTS: A 64-MDCT scanner was performed to 893 patients and thromboembolic disease was demonstrated in 240. Pulmonary thromboembolism was diagnosed in 218 patients. It was concomitant with deep venous thrombosis in 79 patients (36%) and isolated in the rest. Thirty five of the 218 patients with pulmonary thromboembolism had radiological evidence of right ventricular overload. Twenty two patients (10%) had an isolated deep venous thrombosis. In 65 patients with pulmonary thromboembolism (30%) a possibly new or old malignant lesion, was observed. Seventy one of 653 patients without evidence of thromboembolic disease had potentially pathological findings on CT. CONCLUSIONS: The combined use of CT pulmonary arteriography and venography using a 64 MDCT scanner increases the diagnostic yield of the procedure for thromboembolic disease. It also allows the diagnosis of other related conditions, specially malignant tumors.

[Myocardial lipids and creatine measured by magnetic resonance spectroscopy among patients with heart failure]. / Determinaciones de niveles de creatina y lípidos mediante espectroscopia por resonancia magnética en miocardio de pacientes con insuficiencia cardiaca no isquémica.

BACKGROUND: Heart failure (HF) is characterized, among other features, by the development of alterations in myocardial energy metabolism, involving a decrease in glucose utilization and increased free fatty acid uptake by cardiomyocytes, associated with decreased deposits of high-energy phosphates (creatine phosphate/creatine transporter). Magnetic resonance (MR) imaging allows a direct and noninvasive assessment of myocardial metabolites. AIM: To measure myocardial creatine and lipids by MR spectroscopy among patients with HF. MATERIAL AND METHODS: Cardiac MR spectroscopy (1.5 Tesla) with Hydrogen antenna and single voxel acquisition was performed in five patients with non-ischemic heart failure, aged 58 ± 9.7 years, (60% males) and 5 healthy volunteers matched for age and sex. We analyzed the signals of creatine (Cr), lipids (L) and water (W) in the interventricular septum, establishing the water/lipid (W/L) and water/creatine (W/Cr) index to normalize the values obtained. RESULTS: Among patients, left ventricular ejection fraction was 32 ± 6.9%, 60% were in functional capacity II, 60% had hypertension and one was diabetic. Spectroscopic curves showed a depletion of total Cr, evidenced by the W/ Cr index, among patients with heart failure, when compared with healthy controls (1.46 ± 1.21 and 5.96 ± 2.25 respectively, p < 0,05). Differences in myocardial lipid content, measured as the W/L index, were not significant (5.06 ± 2.66 and 1.80 ± 1.62 respectively, p = 0.08). CONCLUSIONS: Among patients with heart failure of non-ischemic etiology, there is a depletion of creatine levels measured by MR spectroscopy.

Enhancement of visual perception with use of dynamic cues.

UNLABELLED: Institutional review board approval and signed informed consent were not needed, as medical images included in public databases were used in this study. The purpose of this study was to improve the detection of microcalcifications on mammograms and lung nodules on chest radiographs by using the dynamic cues algorithm and the motion and flickering sensitivity of the human visual system (HVS). Different sets of mammograms from the Mammographic Image Analysis Society database and chest radiographs from the Japanese Society of Radiological Technology database were presented statically, as is standard, and in a video sequence generated with the dynamic cues algorithm. Nine observers were asked to rate the presence of abnormalities with a five-point scale (1, definitely not present; 5, definitely present). The data were analyzed with receiver operating characteristic (ROC) techniques and the Dorfman-Berbaum-Metz method. The video sequence generated with the dynamic cues algorithm increased the rate of detection of microcalcifications by 10.2% (P = .002) compared with that obtained with the standard static method, as measured by the area under the ROC curve. Similar results were obtained for lung nodules, with an increase of 12.3% (P = .0054). The increase in the rate of correct detection did not come just from the image contrast change produced by the algorithm but also from the fact that image frames generated with the dynamic cues algorithm were put together in a video sequence so that the motion sensitivity of the HVS could be used to facilitate the detection of low-contrast objects. SUPPLEMENTAL MATERIAL: http://radiology.rsnajnls.org/cgi/content/full/250/2/551/DC1.

Carotid artery dissection: endovascular treatment. Report of 12 patients.

OBJECTIVE: The purpose of this article is to report our experience with endovascular treatment of internal carotid artery (ICA) dissection with the use of stents. BACKGROUND: Carotid dissection is an important cause of ischemic stroke in young and middle-aged patients. There are some patients in whom invasive management is recommended. METHODS: Twelve patients (eight females, four males), mean age of 50 years (range 35-80 years) with ICA dissection, were treated with the endovascular approach during a 24-month period. Patients included in this study underwent magnetic resonance (MR) and digital subtraction angiography (DSA) for diagnosis. Over this time period, 162 patients with ICA dissections were seen at our institution. Indications for endovascular treatment were: recurrent ischemic events despite adequate anticoagulant treatment in seven cases, contraindication to anticoagulation in four cases, and one case with significant mismatch between diffusion and perfusion weighted MR. Eleven dissections were spontaneous and one was traumatic. The follow-up was performed clinically with Doppler ultrasound (US) and MR at 6, 12, and 24 months. RESULTS: Stent deployment was successful in all cases. Acute symptoms were resolved in 66.7% of patients. No patients deteriorated their neurological status. There were no new clinical events, stent stenosis or occlusion on 24 months follow-up. CONCLUSION: Our results showed an excellent clinical outcome of the treated patients. This suggests promising results with the use of endovascular treatment in selected patients.

Embolización de colaterales portosistémicas espontáneas como tratamiento de la encefalopatía hepática refractaria / Embolization of spontaneous portosystemic shunts as treatment for refractory hepatic encephalopathy

BACKGROUND: Hepatic encephalopathy (HE) is a common complication of cirrhosis associated with a reduced survival. The presence of high-flux spontaneous porto-systemic shunts can induce HE even in patients with preserved liver function. AIM: To evaluate the effect of spontaneous porto-systemic shunt embolization (SPSE) over HE and its long-term evolution. MATERIAL AND METHODS: Retrospective analysis of 11 patients (91% males) with severe HE non-responsive to medical treatment in whom a SPSE was performed. The grade of HE (employing West Haven score), survival, MELD and Child-Pugh score, ammonia levels, degree of disability (employing the modified Rankin scale (mRs)) were evaluated before and at thirty days after procedure. RESULTS: The most common etiology found was non-alcoholic steatohepatitis (63.6%). A reduction of at least two score points of HE was observed in all patients after thirty days. There was a significant reduction on median (IQR) West Haven score from 3 (2-3) at baseline to 1 (0-1) after the procedure (p < 0.01). Twelve months survival was 63.6%. There was a decrease in median ammonia level from 106.5 (79-165) (ug/dL) to 56 (43-61) after SPSE (p = 0.006). The median mRS score before and after the procedure was 3 (3-5) and 1 (1-2.5), respectively (p < 0.01). Conclusions: According to our experience, SPSE is a feasible and effective alternative to improve HE and functionality of patients with refractory EH.

Foraging Behaviour in Magellanic Woodpeckers Is Consistent with a Multi-Scale Assessment of Tree Quality.

Theoretical models predict that animals should make foraging decisions after assessing the quality of available habitat, but most models fail to consider the spatio-temporal scales at which animals perceive habitat availability. We tested three foraging strategies that explain how Magellanic woodpeckers (Campephilus magellanicus) assess the relative quality of trees: 1) Woodpeckers with local knowledge select trees based on the available trees in the immediate vicinity. 2) Woodpeckers lacking local knowledge select trees based on their availability at previously visited locations. 3) Woodpeckers using information from long-term memory select trees based on knowledge about trees available within the entire landscape. We observed foraging woodpeckers and used a Brownian Bridge Movement Model to identify trees available to woodpeckers along foraging routes. Woodpeckers selected trees with a later decay stage than available trees. Selection models indicated that preferences of Magellanic woodpeckers were based on clusters of trees near the most recently visited trees, thus suggesting that woodpeckers use visual cues from neighboring trees. In a second analysis, Cox's proportional hazards models showed that woodpeckers used information consolidated across broader spatial scales to adjust tree residence times. Specifically, woodpeckers spent more time at trees with larger diameters and in a more advanced stage of decay than trees available along their routes. These results suggest that Magellanic woodpeckers make foraging decisions based on the relative quality of trees that they perceive and memorize information at different spatio-temporal scales.

Gastric cancer after Roux-en-Y gastric bypass.

Roux-en-Y gastric bypass (RYGBP) is one of the most commonly performed surgical procedures for morbid obesity. Several complications that may develop in the short- and long-term have been reported. We present a patient who presented with cancer in the bypassed stomach 8 years after RYGBP. Although the development of this lesion is rare and only a few cases have been reported, there are aspects worthy of discussion. Several monitoring, diagnostic and therapeutic alternatives are analyzed.

[Double-balloon enteroscopy: experience in the Hospital de Especialidades del Centro Médico Nacional Siglo XXI IMSS, Mexico City]. / Enteroscopia de doble balón: experiencia en el hospital de Especialidades del Centro Médico Nacional Siglo XXI, IMSS, Ciudad de México.

UNLABELLED: The methods used for the study of the small bowel are not ideal. Double-balloon enteroscopy is a new alternative with therapeutic potential. OBJECTIVE: Evaluate the utility, efficacy and safety of double-balloon enteroscopy in Mexico. MATERIAL AND METHODS: Adult patients seen in the Hospital de Especialidades Centro Médico Nacional Siglo XXI, Mexico City who were being studied for: chronic diarrhea, obscure gastrointestinal hemorrhage, weight-loss and chronic anemia were included in the study. Anterograde (oral) and retrograde (anal) approaches were used and study time, findings and complications were evaluated. RESULTS: Thirty-one enteroscopies were performed, 15 were anterograde, 8 retrograde and 8 were performed via both routes, in 23 patients studied between February and October, 2004; 10 of them were women and 13 men with ages ranging from 25 to 80 years. Fourteen patients were sedated and 9 patients were anesthetized. Study time varied form 55 to 90 minutes. With the anterograde route the ileum was reached in 56.6% of cases, 39.1% the jejunum and only in one patient (4.3%) the whole intestine was explored. With the retrograde route in 62.5% of cases the jejunum was explored and 37.5% the ileum. Four patients with obscure gastrointestinal bleeding and 1 patient with chronic anemia had vascular ecstasies, and in 40% of patients there was no identifiable cause. In 2 patients with intestinal stenosis biopsies revealed intestinal lymphoma in one and ischemic injury in another one. The adverse effects were mild and transitoru. CONCLUSIONS: Double-balloon enteroscopy is a safe diagnostic and therapeutic method that is useful in cases of obscure hemorrhage, chronic anemia; small bowel pathology was found in 64.7% of cases.

Embolization of incompetent pelvic veins for the treatment of recurrent varicose veins in lower limbs and pelvic congestion syndrome.

PURPOSE: We present our experience with embolization of incompetent pelvic veins (IPV) in women with recurrence of varicose veins (VV) in lower limbs, as well as symptoms of pelvic congestion syndrome (PCS), after first surgery. In addition, we evaluated the effects of embolization in decreasing the symptoms of VV before surgery as well as its effects on PCS symptoms. MATERIALS AND METHODS: We included 10 women who had consulted a vascular surgeon because of recurrent VV in lower limbs after surgery. All of these patients were included in the study because they also had symptoms of PCS, probably due to IPV. In patients who had confirmed IPV, we performed embolization before a second surgery. VV and PCS were assessed before and at 3 months after embolization (before the second surgery) using a venous clinical severity score (VCSS) and a visual analog pain scale (VAS), respectively. Patients were controlled between 3 and 6 months after embolization. Paired Student t test analysis was used for comparing data before and after embolization. RESULTS: Fifteen vein segments in 10 women were suitable for embolization. There was a significant (p < 0.001) decrease of VCSS after embolization, and recurrence of VV was not detected within a period of 6 months. There was also significant (p < 0.01) relief of chronic pelvic pain related to PCS evaluated using VAS at 3 months after embolization. CONCLUSION: Embolization decreases the risk of VV recurrence after surgery and also improves PCS symptoms in women with VV in lower limbs and IPV.

Natriuretic peptide type-B can be a marker of reperfusion in patients with pulmonary thromboembolism subjected to invasive treatment.

This study was intended to investigate changes in cardiac biomarkers and pulmonary hemodynamic effects of invasive treatment in patients with intermediate-risk (hemodynamic stability with evidence of right ventricle dysfunction and/or myocardial injury) pulmonary embolism. Also, to also evaluate if natriuretic peptide type-B (NT-proBNP) plasma levels are associated with right ventricle function and pulmonary arterial pressures. Interventional study: Fourteen normotensive adult patients with acute and radiologically massive pulmonary embolism plus positive biomarkers and evidences of right ventricle dysfunction underwent invasive pulmonary angiography for invasive treatment consisting on mechanical thrombus fragmentation and catheter-directed intrathrombus thrombolysis. Angiography was repeated after 12-24 h to reevaluate perfusion status. Plasma biomarkers were monitored before and 8-h after intervention. Biomarkers were initially elevated in all patients. Eleven patients (78.6%) exhibited significant angiographic reperfusion. NT-proBNP and mean pulmonary arterial pressure decreased significantly in all of them [3693 (1803, 8862) to 1951 (1309, 7918) pg/ml; P = 0.008) and 40.0 (24.0, 46.0) to 22.0 (14.0, 27.0) mmHg; P = 0.003, respectively]. No significant variation was observed in troponin-T levels. In patients with high-risk pulmonary embolism, NT-proBNP plasma levels experience rapid and significant reduction after successful invasive treatment. In pulmonary embolism, serial measurements of NT-proBNP could be useful as a tracking tool to assess the success or failure of the thrombolytic treatment.

Seguimiento clínico de neonatos con Enterocolitis necrosante / Clinical folow-up in newborn infants with necrotizing enterocolitis

La enterocolitis necrosante (ECN) es la urgencia gastrointestinal más frecuente en lactantes pretérmino. En el Hospital Roosevelt la mortalidad secundaria a la misma fue del 40% en el año 2009. Según literatura internacional, de los pacientes que sobreviven, aproximadamente 25% presentarán secuelas de larga duración como retraso en el neurodesarrollo y desnutrición; sin embargo, en Guatemala no se tienen datos al respecto.

New frequency translation technique for FM-CW reflectometry.

In broadband microwave reflectometry, coherent detection is widely used to obtain the phase information and to improve the systems sensitivity, both in diagnostics measuring the electronic density profile and plasma fluctuations. Coherent detection uses a translated version of the probing signal to guarantee a stable intermediate frequency. Here, a novel technique to generate the frequency translation by double frequency conversion is presented and its advantages over the commonly used single frequency conversion techniques employing image rejection mixers are discussed. The results obtained with the new frequency translator modules developed for the three JET FM-CW reflectometers, operating successfully at JET since mid-2009, are presented.

[Chemoembolization of hepatocarcinoma: report of two cases]. / Quimioembolización hepática en el manejo terapéutico del hepatocarcinoma: Reporte de dos casos.

Chemoembolization is a therapeutic alternative for those patients with hepatocarcinoma that cannot be excised surgically or that are waiting a liver allograft. We report two patients with hepatocarcinoma who were subjected to chemoembolization. A 65 years old male with a chronic liver disease and right lobe hepatocarcinoma, waiting for a liver transplantation, was subjected to two sessions, of chemoembolization four weeks apart. A magnetic resonance showed a 80% reduction of tumor volume one month later. A 72 years old diabetic male with an alcoholic liver disease with two hepatocarcinoma in the right lobe was subjected to two sessions of chemoembolization, separated by four weeks. A magnetic resonance one month later showed the absence of blood flow in both lesions, suggesting complete necrosis.

Systematic and routine analysis of radial correlation reflectometry data in JET.

This paper discusses a tool specially developed for the analysis of radial correlation reflectometry data in JET. The tool, which calculates the correlation length and coherent reflection from the raw data, has been designed for offline analysis and to assist diagnostic operators. After being verified in controlled tests using theoretical signals, the tool is validated by means of a study of ITB plasmas in JET.

TIPSS procedure in the treatment of a single patient after recent heart transplantation because of refractory ascites due to cardiac cirrhosis.

We present the case of a female patient with arrhythmogenic dysplasia of the right ventricle who evolved to refractory heart failure, ascites, and peripheral edema. As a result, heart transplantation was performed. Subsequently, refractory ascites impaired the patient's respiratory function, resulting in prolonged mechanical ventilation. She was successfully treated with transjugular intrahepatic portosystemic shunt (TIPSS) placement, which allowed satisfactory weaning of ventilatory support.