Hepatocellular Carcinoma Epigenetic Patterns Correspond to Differences in Ethnoracial Status and Treatment Response in a Single-Center Retrospective Study.

PURPOSE: To correlate epigenetic patterns with ethnoracial status and locoregional therapy (LRT) response in patients with hepatocellular carcinoma (HCC). MATERIALS AND METHODS: DNA and RNA were extracted from 47 distinct formalin-fixed paraffin-embedded tumor samples from 42 patients with HCC (n = 14 Black, n = 19 White, n = 9 Hispanic). LRT response was determined using computed tomography (CT) or magnetic resonance (MR) imaging 3 months posttreatment of 35 tumors (n = 22 complete response, n = 13 retreatment candidates). RNA expression and DNA methylation were used to stratify patients by ethnoracial status and treatment response using partial least-squares discriminant analysis (PLS-DA). Results were validated using hierarchical clustering. Ingenuity pathway analysis was performed to identify upstream regulators and pathways. RESULTS: PLS-DA identified 100 genes and 12 methylated regions that differentiated tumors from Black from White/Hispanic patients. Hierarchical clustering clustered samples with the top 16 genes or the top 5 methylation regions. Dysregulated pathways included adrenomedullin pathway (P = .030), EIF2 signaling (P = .007), and several metabolic pathways. AGTR1 (log2fold = 1.59) and GSTM3 (log2fold = 2.53) represented potential differentially expressed therapeutic targets. PLS-DA identified 100 genes and 150 methylation regions that differentiated between complete responders and retreatment candidates. Hierarchical clustering clustered samples with the top 30 genes or the top 13 methylation regions. Dysregulated pathways included metabolic and DNA repair-related pathways. ASAP2 (log2fold = 0.29) and RAD50 (log2fold = 0.22) represented potential differentially expressed therapeutic targets. CONCLUSIONS: Variation in gene expression and DNA methylation patterns in patients with HCC corresponded to ethnoracial status and LRT response. These initial results suggest tumor profiling has the potential to close ethnoracial disparities and improve treatment stratification.

Post-transplant biliary complications using liver grafts from deceased donors older than 70 years: Retrospective case-control study.

BACKGROUND: The shortage of liver grafts and subsequent waitlist mortality led us to expand the donor pool using liver grafts from older donors. AIM: To determine the incidence, outcomes, and risk factors for biliary complications (BC) in liver transplantation (LT) using liver grafts from donors aged > 70 years. METHODS: Between January 1994 and December 31, 2019, 297 LTs were performed using donors older than 70 years. After excluding 47 LT for several reasons, we divided 250 LTs into two groups, namely post-LT BC (n = 21) and without BC (n = 229). This retrospective case-control study compared both groups. RESULTS: Choledocho-choledochostomy without T-tube was the most frequent technique (76.2% in the BC group vs 92.6% in the non-BC group). Twenty-one patients (8.4%) developed BC (13 anastomotic strictures, 7 biliary leakages, and 1 non-anastomotic biliary stricture). Nine patients underwent percutaneous balloon dilation and nine required a Roux-en-Y hepaticojejunostomy because of dilation failure. The incidence of post-LT complications (graft dysfunction, rejection, renal failure, and non-BC reoperations) was similar in both groups. There were no significant differences in the patient and graft survival between the groups. Moreover, only three deaths were attributed to BC. While female donors were protective factors for BC, donor cardiac arrest was a risk factor. CONCLUSION: The incidence of BC was relatively low on using liver grafts > 70 years. It could be managed in most cases by percutaneous dilation or Roux-en-Y hepaticojejunostomy, without significant differences in the patient or graft survival between the groups.

Regular Consumption of Cocoa and Red Berries as a Strategy to Improve Cardiovascular Biomarkers via Modulation of Microbiota Metabolism in Healthy Aging Adults.

The aim of the present study was to analyze the effects of cocoa flavanols and red berry anthocyanins on cardiovascular biomarkers, such as homocysteine, angiotensin-converting enzyme (ACE), nitric oxide (NO), flow-mediated vasodilation (FMD), blood pressure and lipid profile. Additionally, we aimed to ascertain their possible interactions with microbiota related metabolites, such as secondary bile acids (SBA), short-chain fatty acids (SCFA) and trimethylamine N-oxide (TMAO). A randomized, parallel-group study, single-blind for the research team, was performed on 60 healthy volunteers between the ages of 45 and 85, who consumed 2.5 g/day of cocoa powder (9.59 mg/day of total flavanols), 5 g/day of a red berry mixture (13.9 mg/day of total anthocyanins) or 7.5 g/day of a combination of both for 12 weeks. The group that had consumed cocoa showed a significant reduction in TMAO (p = 0.03) and uric acid (p = 0.01) levels in serum, accompanied by an increase in FMD values (p = 0.03) and total polyphenols. corrected by creatinine (p = 0.03) after the intervention. These latter values negatively correlated with the TMAO concentration (R = -0.57, p = 0.02). Additionally, we observed an increase in carbohydrate fermentation in the groups that had consumed cocoa (p = 0.04) and red berries (p = 0.04) between the beginning and the end of the intervention. This increase in carbohydrate fermentation was correlated with lower levels of TC/HDL ratio (p = 0.01), systolic (p = 0.01) and diastolic blood pressure (p = 0.01). In conclusion, our study showed a positive modulation of microbiota metabolism after a regular intake of cocoa flavanols and red berry anthocyanins that led to an improvement in cardiovascular function, especially in the group that consumed cocoa.

Isolated left ventricular apical hypoplasia: case report.

Background: Isolated left ventricular apical hypoplasia (ILVAH) is a rare, probably congenital, cardiac condition recently reported in the last two decades. Although most cases are asymptomatic or mildly symptomatic, some severe and fatal cases have been reported, leading to more efforts for appropriate diagnosis and treatment. We describe the first, and severe, case of this pathology in Peru and Latin America. Case summary: A 24-year-old male with a history of long-standing alcohol and illicit drug use presented with symptoms of heart failure (HF) and atrial fibrillation (AF). Transthoracic echocardiography showed biventricular dysfunction along with spherical left ventricle, abnormal papillary muscles' origin from the left ventricular apex, and an elongated right ventricle wrapping around the deficient left ventricular apex. Cardiac magnetic resonance confirmed these findings and revealed subepicardial fatty replacement at the left ventricular apex. The diagnosis of ILVAH was made. He was discharged from hospital with carvedilol, enalapril, digoxin, and warfarin. Eighteen months later he remains mildly symptomatic at New York Heart Association functional class II without worsening HF nor thrombo-embolism. Discussion: This case highlights the usefulness of multimodality non-invasive cardiovascular imaging for accurate diagnosis of ILVAH as well as the importance of close follow-up and treatment of established complications (HF and AF).

Tip-Induced and Electrical Control of the Photoluminescence Yield of Monolayer WS2.

The photoluminescence (PL) of monolayer tungsten disulfide (WS2) is locally and electrically controlled using the nonplasmonic tip and tunneling current of a scanning tunneling microscope (STM). The spatial and spectral distribution of the emitted light is determined using an optical microscope. When the STM tip is engaged, short-range PL quenching due to near-field electromagnetic effects is present, independent of the sign and value of the bias voltage applied to the tip-sample tunneling junction. In addition, a bias-voltage-dependent long-range PL quenching is measured when the sample is positively biased. We explain these observations by considering the native n-doping of monolayer WS2 and the charge carrier density gradients induced by electron tunneling in micrometer-scale areas around the tip position. The combination of wide-field PL microscopy and charge carrier injection using an STM opens up new ways to explore the interplay between excitons and charge carriers in two-dimensional semiconductors.

Design and implementation of a device based on an off-axis parabolic mirror to perform luminescence experiments in a scanning tunneling microscope.

We present the design, implementation, and illustrative results of a light collection/injection strategy based on an off-axis parabolic mirror collector for a low-temperature Scanning Tunneling Microscope (STM). This device allows us to perform STM induced Light Emission (STM-LE) and Cathodoluminescence (STM-CL) experiments and in situ Photoluminescence (PL) and Raman spectroscopy as complementary techniques. Considering the Étendue conservation and using an off-axis parabolic mirror, it is possible to design a light collection and injection system that displays 72% of collection efficiency (considering the hemisphere above the sample surface) while maintaining high spectral resolution and minimizing signal loss. The performance of the STM is tested by atomically resolved images and scanning tunneling spectroscopy results on standard sample surfaces. The capabilities of our system are demonstrated by performing STM-LE on metallic surfaces and two-dimensional semiconducting samples, observing both plasmonic and excitonic emissions. In addition, we carried out in situ PL measurements on semiconducting monolayers and quantum dots and in situ Raman on graphite and hexagonal boron nitride (h-BN) samples. Additionally, STM-CL and PL were obtained on monolayer h-BN gathering luminescence spectra that are typically associated with intragap states related to carbon defects. The results show that the flexible and efficient light injection and collection device based on an off-axis parabolic mirror is a powerful tool to study several types of nanostructures with multiple spectroscopic techniques in correlation with their morphology at the atomic scale and electronic structure.

Polyphenols' Effect on Cerebrovascular Health.

Polyphenols are a wide group of plant components that include a high number of individual compounds and are present in foods, dietary supplements, and drugs. Many of them have shown pharmacological effects, are used in cardiovascular disease prevention, and not as many have been assayed in cancer treatment or co-treatment. In the last few years, however, the research on polyphenols' implications in healthy aging, especially in neurodegeneration and cognition improvement, has increased dramatically. Most of the results found in this sense are again related to the capacity of some specific polyphenols to regulate the blood flow, but this time at the cerebral level, and to protect the endothelium at this same level. In this thorough review, we want to concentrate precisely on the effect of polyphenols on cerebrovascular homeostasis, reviewing the mechanisms that underline this effect and the radiological methods and endogenous biomarkers that are used in human trials aimed at showing the beneficial effect of polyphenols or polyphenol rich foods on neuroprotection and cognition function.

[Effects of pharmaceutical counseling on the effectiveness of anticoagulation in patients with atrial fibrillation]. / Impacto de la atención farmacéutica en la calidad del tratamiento con acenocumarol en pacientes con fibrilación auricular.

BACKGROUND: Vitamin K antagonists such as acenocoumarol and warfarin are usually indicated for the treatment of Atrial Fibrillation (AF). The Therapeutic Range Time (TRT) is a quality of treatment indicator. Values greater than 65% are associated with significantly lower stroke and bleeding rates. Proper pharmaceutical care improves TRT. AIM: To evaluate the impact of pharmaceutical care in patients with AF treated with acenocoumarol. MATERIAL AND METHODS: We studied 41 patients using acenocoumarol for AF aged 71 ± 11 years (43% women). They received pharmaceutical counseling during 12 weeks. TRT was calculated retrospectively for the year before counseling and prospectively during the intervention period. RESULTS: After receiving pharmaceutical counseling TRT improved from 29% at baseline to 46% at the end of the intervention (p < 0.01). After pharmaceutical care, the adherence of patients to drug treatment improved from 27% at baseline to 85% at the end of the study. The user satisfaction survey of the pharmaceutical care received showed a high degree of patient satisfaction. CONCLUSIONS: Pharmaceutical care in patients with oral anticoagulant treatment improves TRT of anticoagulation. It is accepted and positively evaluated by patients.

Impacto de la atención farmacéutica en la calidad del tratamiento con acenocumarol en pacientes con fibrilación auricular / Effects of pharmaceutical counseling on the effectiveness of anticoagulation in patients with atrial fibrillation

Background: Vitamin K antagonists such as acenocoumarol and warfarin are usually indicated for the treatment of Atrial Fibrillation (AF). The Therapeutic Range Time (TRT) is a quality of treatment indicator. Values greater than 65% are associated with significantly lower stroke and bleeding rates. Proper pharmaceutical care improves TRT. Aim: To evaluate the impact of pharmaceutical care in patients with AF treated with acenocoumarol. Material and Methods: We studied 41 patients using acenocoumarol for AF aged 71 ± 11 years (43% women). They received pharmaceutical counseling during 12 weeks. TRT was calculated retrospectively for the year before counseling and prospectively during the intervention period. Results: After receiving pharmaceutical counseling TRT improved from 29% at baseline to 46% at the end of the intervention (p < 0.01). After pharmaceutical care, the adherence of patients to drug treatment improved from 27% at baseline to 85% at the end of the study. The user satisfaction survey of the pharmaceutical care received showed a high degree of patient satisfaction. Conclusions: Pharmaceutical care in patients with oral anticoagulant treatment improves TRT of anticoagulation. It is accepted and positively evaluated by patients.

Neurocognitive Effects of Cocoa and Red-Berries Consumption in Healthy Adults.

In recent decades, the elderly population has increased at higher rates than any other population group, resulting in an increase in age-related diseases such as neurodegenerative and cognitive impairment. To address this global health problem, it is necessary to search for new dietary strategies that can prevent the main neurocognitive problems associated with the ageing process. Therefore, the aim of the present study was to analyze the effect of cocoa flavanols and red berry anthocyanins on brain-derived neurotrophic factor (BDNF) and nerve growth factor receptor (NGF-R) and to stablish the possible improvement in cognitive performance by using a battery of neurocognitive tests that included the Verbal Learning Test Spain-Complutense, the Spatial Recall Test 10/36 BRB-N, the Wechsler Adult Intelligence Scale III and IV, the STROOP Task and the Tower of London Test. A randomized, double-blind, parallel-group study was performed in 60 healthy volunteers between 50 and 75 years old who consumed a cocoa powder, a red berries mixture or a combination of both for 12 weeks. After the intervention, we observed a reduction in the time needed to start (p = 0.031) and finish (p = 0.018) the neurocognitive test known as the Tower of London in all groups, but the decrease in time to finish the task was more pronounced in the intervention with the combination of cocoa-red berries group. We failed to show any significant difference in BDNF and NGF-R sera levels. However we found a negative correlation between BDNF and the number of movements required to finish the TOL in women (p = 0.044). In conclusion, our study showed an improvement in executive function, without any change in neurotrofin levels, for all intervention arms.

Tunneling-current-induced local excitonic luminescence in p-doped WSe2 monolayers.

We have studied the excitonic properties of exfoliated tungsten diselenide (WSe2) monolayers transferred to gold substrates using the tunneling current in a Scanning Tunneling Microscope (STM) operated in air to excite the light emission locally. In obtained spectra, emission energies are independent of the applied bias voltage and resemble photoluminescence (PL) results, indicating that, in both cases, the light emission is due to neutral and charged exciton recombination. Interestingly, the electron injection rate, that is, the tunneling current, can be used to control the ratio of charged to neutral exciton emission. The obtained quantum yield in the transition metal dichalcogenide (TMD) is ∼5 × 10-7 photons per electron. The proposed excitation mechanism is the direct injection of carriers into the conduction band. The monolayer WSe2 presents bright and dark defects spotted by STM images performed under UHV. STS confirms the sample as p-doped, possibly as a net result of the observed defects. The presence of an interfacial water layer decouples the monolayer from the gold support and allows excitonic emission from the WSe2 monolayer. The creation of a water layer is an inherent feature of the sample transferring process due to the ubiquitous air moisture. Consequently, vacuum thermal annealing, which removes the water layer, quenches excitonic luminescence from the TMD. The tunneling current can locally displace water molecules leading to excitonic emission quenching and to plasmonic emission due to the gold substrate. The present findings extend the use and the understanding of STM induced light emission (STM-LE) on semiconducting TMDs to probe exciton emission and dynamics with high spatial resolution.

Lack of a Synergistic Effect on Cardiometabolic and Redox Markers in a Dietary Supplementation with Anthocyanins and Xanthophylls in Postmenopausal Women.

Fruits and vegetables are pivotal for a healthy diet due partly to their content in bioactive compounds. It is for this reason that we conducted a parallel study to unravel the possible effect on cardiometabolic parameters of the ingestion of anthocyanins, xanthophylls, or both groups of bioactives together in postmenopausal women. Seventy-two postmenopausal women were randomized into an 8-month parallel study: a group consuming 60 mg/day anthocyanins (Group A), a group consuming 6 mg lutein and 2 mg zeaxanthin per day (Group X), and a third group consuming a combination of anthocyanins and xanthophylls in the same amounts (Group A+X). Non-targeted metabolomic analysis was done in plasma samples at baseline and after the 8-month intervention by HPLC-QTOF-MS. Inflammatory, antioxidant, and cardiometabolic parameters were measured at the beginning of the study and after 4 and 8-months intervention. Compared with baseline values, none of the 8-month treatments significantly (p < 0.05) changed systolic or diastolic blood pressure (BP), plasma C-reactive protein, interleukin 6, vascular cell adhesion molecule-1, intercellular adhesion molecule-1, monocyte chemoattractant protein-1 or matrix metalloproteinases 2 and 9. Only plasma glucose levels were significantly decreased by treatment A+X after 8 months, and the plasma metabolomic profile was clearly affected by all three dietary supplementations after 8 months. In parallel, there was an increase, also for the three groups, in the plasma ferric reducing antioxidant power value that did not show any synergistic effect between the two groups of bioactives. Postmenopausal women could benefit from an increase in anthocyanins and xanthophylls intake, through the consumption of fruits and vegetables rich in these two types of compounds. Accordingly, plasma glucose and, above all, the reducing power in plasma, could be improved.

Construction of protein-functionalized virus-like particles of parvovirus B19.

Decoration of virus-like particles (VLPs) expands the repertory of functions these particles can display. In the last years, VLPs have successfully been used as scaffolds to present different molecules, frequently through the specific reaction of chemical groups on the surface of the particles, or by protein engineering when the presentation of peptides or proteins is the primary goal. VLPs of parvovirus B19 (B19V), have been previously produced in vitro and its stability and ability to assemble into hybrid particles composed of wild-type and chimeric proteins evidenced their potential as research tools. Herein, we report the presentation of functional proteins on the surface of B19V VLPs, through the fusion of the gene coding for the heterologous protein within the gene coding for the structural protein VP2. Two model proteins were used for the construction of chimeras, a lipase from Bacillus pumilus (BplA) and the enhanced green fluorescent protein (EGFP). Both chimeras were folded and successfully assembled in vitro into VLPs. While the BplA chimera exhibited esterase activity, the chimera of EGFP showed no fluorescence. We replaced the EGFP by its fast-folding derivative "super folder GFP" (sfGFP) flanked by larger linkers to increase its movement freedom, which resulted in fluorescent protein able to assemble fluorescent VLPs. These results expand the toolbox for VLP decoration as well as for the construction of new nanobiomaterials.

HIV prevalence, sociodemographic characteristics, and sexual behaviors among transwomen in Mexico City.

OBJECTIVE: To present results from HIV testing, knowledge of HIV status and socioeconomic factors associated with the probability of having a HIV positive result among transwomen (TW) in Mexico. MATERIALS AND METHODS: In 2012, we conducted an HIV seroprevalence survey to 585 TW in Mexico City in three strata: gathering places, the Condesa HIV Clinic and in four detention centers. We estimated the prevalence of HIV in each strata and applied a probit model to the overall sample to analyze factors associated with the probability of a HIV positive result. RESULTS: The prevalence of HIV was 19.8% in meeting places; 31.9% in detention centers and 64% among the participants of the clinic. Age, low education and number of sexual partners was positively associated with HIV. CONCLUSIONS: Results from the study provide relevant information to design HIV prevention interventions tailored to the needs of the TW population.

Sonic versus ultrasonic activation for the cleaning of the root canal after post space preparation: an in vitro study / Activación sónica versus ultrasónica en la limpieza del canal radicular posterior a la preparación del lecho para poste: estudio in vitro

To compare the efficacy of 3 intracanal cleaning protocols used before cementation of prosthetic posts. Material and Methods: 40 anterior teeth received endodontic treatment in hand, using lateral condensation technique. After two weeks, gutta-percha was appropriately removed from the teeth to get the necessary space to install a post. Then, teeth were randomly divided into groups; root surface was treated with chlorhexidine (CHX) activated by ultrasound (US) (group I), with chlorhexidine activated by sonic instrumentation (S) (group II), chlorhexidine without activation (group III) and without treatment (group IV). All teeth were fractured longitudinally getting 2 sections. The middle third of the root canal was microphotographed with a scanning electron microscope (SEM) and the contaminated surface was measured using detritus with ImageJ 1.47. It was analyzed with Kruskal-Wallis-test using GraphPad Prism 5.01. Results: The median percentage of contaminated area of Group I was 20.06 percent, Group II, 19.3 percent; Group III, 36.05 percent; and Group IV, 56.45 percent. Conclusion: There are significant differences among different intracanal cleaning protocols in the removal efficiency of detritus from the root canal, being the activated protocols the most effective ones...

Comparar la eficacia de 3 protocolos de limpieza intraconducto utilizados previo a la cementación de pernos protésicos. Materiales y métodos: A 40 dientes anteriores se les realizó un tratamiento endodóntico en mano, mediante la técnica de condensación lateral. Luego de dos semanas, se realizó la desobturación de los mismos retirando la cantidad de gutapercha que otorgue el espacio necesario para alojar un poste. A continuación, los dientes fueron divididos aleatoriamente en grupos; superficie radicular tratada con clorhexidina (CHX) activado con ultrasonido (US) (grupo I), con clorhexidina activado con instrumental sónico (S) (grupo II), con clorhexidina sin activación (grupo III) y sin ningún tratamiento (grupo IV). Todos los dientes se fracturaron longitudinalmente obteniendo 2 secciones. Se microfotografió el tercio medio del conducto radicular con microscopio electrónico de barrido (MEB) y se midió la superficie contaminada con detritus usando ImageJ 1.47. Se analizó con test Kruskall-Wallis usando GraphPad-Prism 5.01. Resultados: La mediana del porcentaje de área contaminada del Grupo I fue 20,06 por ciento, Grupo II de 19,3 por ciento, Grupo III de 36,05 por ciento y Grupo IV de 56,45 por ciento. Conclusión: Existen diferencias significativas entre los distintos protocolos de limpieza intraconducto en la eficacia de eliminación de detritus del conducto radicular, siendo los protocolos activados más eficientes...

HIV prevalence, sociodemographic characteristics, and sexual behaviors among transwomen in Mexico City / Prevalencia de VIH, características sociodemográficas y comportamientos en mujeres transgénero en la Ciudad de México

Objective. To present results from HIV testing, knowledge of HIV status and socioeconomic factors associated with the probability of having a HIV positive result among transwomen (TW) in Mexico. Materials and methods. In 2012, we conducted an HIV seroprevalence survey to 585 TW in Mexico City in three strata: gathering places, the Condesa HIV Clinic and in four detention centers. We estimated the prevalence of HIV in each strata and applied a probit model to the overall sample to analyze factors associated with the probability of a HIV positive result. Results. The prevalence of HIV was 19.8% in meeting places; 31.9% in detention centers and 64% among the participants of the clinic. Age, low education and number of sexual partners was positively associated with HIV. Conclusions. Results from the study provide relevant information to design HIV prevention interventions tailored to the needs of the TW population.

Objetivo. Identificar la prevalencia, conocimiento de estatus de VIH y factores socioeconómicos asociados con la probabilidad de tener un resultado de VIH positivo en mujeres transgénero (MT) en México. Material y métodos. En 2012, se realizó una encuesta de seroprevalencia de VIH a 585 MT en sitios de encuentro, centros penitenciarios y una clínica de VIH, en la Ciudad de México. Se estimó la prevalencia de VIH en cada estrato y se aplicó un modelo probit para analizar los factores asociados con la probabilidad de un resultado positivo. Resultados. La prevalencia de VIH fue de 19.8% en lugares de encuentro y de 32% en centros de detención; a su vez, 64% de las participantes en la clínica eran VIH positivas. La edad, el bajo nivel de educación y el número de parejas sexuales se asoció positivamente con VIH. Conclusiones. Los resultados del estudio aportan información relevante para el diseño de intervenciones de prevención de VIH de acuerdo con las necesidades de esta población.

Valoración en un solo paso del potencial donante renal: Angiografía y urografía por RM con correlación quirúrgica / One-step MR angiography and urography in the evaluation of potential renal living donors.

Objetivos. Evaluar el rendimiento diagnóstico de la angiografía renal (ARM) y urografía (URM) por Resonancia Magnética (RM) en potenciales donantes de riñón mediante la correlación con hallazgos quirúrgicos. Materiales y Métodos. Se evaluaron 55 potenciales donantes mediante protocolo angiográfico y urográfico en múltiples fases en un resonador de 1,5 T. La ARM valoró la existencia de variantes anatómicas o alteraciones estructurales arteriales o venosas y la URM valoró el parénquima renal y el sistema colector en fases nefrográfica y excretora. Los resultados fueron comparados con hallazgos quirúrgicos. Resultados. La correlación se realizó en 42 donantes efectivos. En ellos, se observó una especificidad de la ARM del 94% y una exactitud diagnóstica del 93%. Se identificaron variantes anatómicas y alteración estructural arterial en el 29% de los pacientes. La valoración venosa y urográfica de la RM resultó concordante quirúrgicamente en todos los casos. Conclusión. Las imágenes de RM proveen un método seguro y eficaz para la valoración prequirúrgica renal de forma integral en potenciales donantes de riñón.

Objectives. To evaluate diagnostic accuracy of renal MRangiography(MRA) and MR- urography (MRU) in the assessment of normal anatomy and renal vascular pathology in potential renal living donors compared with surgical findings. Materials and Methods. Evaluation of 55 potential living donors performing one-step MR angiography and MR urography in a 1.5 T magnet. MRA evaluated the presence of anatomic variants or arterial or venous pathologic conditions. MRU depicted renal parenchyma anatomy and collector system. These results were compared with surgical findings. Results. MRA and MRU findings were actually compared with surgical findings in 42 effective donors. MRA specificity was 94 % and diagnostic accuracy was 93 %. Anatomic variants and arterial structural abnormalities were detected in 29 % of patients. Venous and excretory surgical findings were consistent in 100 % of cases. Conclusion. One-step MRA and MRU constitutes an accurate method for pre-operative assessment of renovascular and excretory anatomy in potential living donors.

Evidence for two retinoid cycles in the cone-dominated chicken eye.

In the classic retinoid cycle, 11-cis retinol is synthesized in the retinal pigment epithelium (RPE) by two enzymes: Isomerase I (RPE65) and lecithin:retinol acyltransferase (LRAT). The purpose of this study is to provide experimental evidence for two active isomerases in the cone-dominated chicken eye: an LRAT-dependent Isomerase I in the RPE and an ARAT (acyl CoA:retinol acyltransferase)-dependent isomerase (Isomerase II) in the retina. First, we show that whole chicken retina in vitro, removed from the RPE/choroid and sclera, produces 11-cis retinoids upon light exposure, indicating the existence of RPE-independent isomerase (Isomerase II) activity in the retina. Reverse transcriptase polymerase chain reaction studies show high levels of RPE65 expression in the RPE, low levels in the retina, and none in primary Muller cell cultures, indicating the presence of Isomerase I in the RPE and a minimal amount in the retina. Activities of the RPE and retina isomerases were then measured by enzyme assays with specific enzyme inhibitors. 2,2'-Bipyridine, a known Isomerase I inhibitor, and N-ethylmaleimide (NEM), a known LRAT inhibitor, significantly reduced Isomerase I activity but not Isomerase II activity. Progesterone, a known ARAT inhibitor, completely blocked Isomerase II activity but not Isomerase I activity. Thus, this study reports novel results for distinguishing the biochemical properties of Isomerase I from those of Isomerase II, as well a difference in their locations in the chicken eye. On the basis of these differences, the cone-dominated chicken eye must contain two retinoid cycles: a classic visual cycle for retinoid exchange between the RPE and the retina supported by Isomerase I in the RPE and an additional visual cycle for retinoid processing in the retina supported by Isomerase II.

Alteraciones morfologicas del corpus callosum en esquizofrenicos / Morphological alterations of the corpus callosum in schizophrenia

El objetivo del presente trabajo es el estudio de la superficie del corpus callosum (CC) y de la relación de ésta con su perímetro en el plano sagital medio de imágenes de resonancia magnética en dos grupos de sujetos femininos, diestros, apareados por la edad, uno integrado por 25 controles y otro por 31 esquizofrénicas residuales (DSM IV), a fin de determinar probales alternaciones en las esquizofrénicas. Cada grupo fue dividido en los sub-grupos: E ó 54 (con edades de 40 a 54 años), y E > 54 (mayores de 54 a 68 años). Las medias + ES (cm2) de las superficies del CC de controles E ó 54 y E > 54 son respectivamente 7,09 0,42 y 8,97 + 0,62 (p < 0,01) y de las esquizofrénicas E ó 54 u E > 54 7,61 + 0,24 y 6,60 + 0,29 (p < 0,05). Entre ambos sub-grupos E > 54 la diferencia es significativa (p < 0,01). Las significaciones fueron determinadas por análisis de varianza. Las correlaciones (r), entre edad y superficie, calculadas con la totalidad de casos de cada grupo, son: 0,55 (p < 0,05) en controles y - 0,45 (p < 0,02) en esquizofrénicas. Se concluye que con el incremento de la edad en las esquizofrénicas disminuye significativamente la superficie del CC alterándose la proporcionalidad entre superficie y perímetro, mientras que en las controles el incremento de ambos permite conservar tal proporcionalidad.

Alteraciones morfologicas del corpus callosum en esquizofrenicos / Morphological alterations of the corpus callosum in schizophrenia

El objetivo del presente trabajo es el estudio de la superficie del corpus callosum (CC) y de la relación de ésta con su perímetro en el plano sagital medio de imágenes de resonancia magnética en dos grupos de sujetos femininos, diestros, apareados por la edad, uno integrado por 25 controles y otro por 31 esquizofrénicas residuales (DSM IV), a fin de determinar probales alternaciones en las esquizofrénicas. Cada grupo fue dividido en los sub-grupos: E ó 54 (con edades de 40 a 54 años), y E > 54 (mayores de 54 a 68 años). Las medias + ES (cm2) de las superficies del CC de controles E ó 54 y E > 54 son respectivamente 7,09 0,42 y 8,97 + 0,62 (p < 0,01) y de las esquizofrénicas E ó 54 u E > 54 7,61 + 0,24 y 6,60 + 0,29 (p < 0,05). Entre ambos sub-grupos E > 54 la diferencia es significativa (p < 0,01). Las significaciones fueron determinadas por análisis de varianza. Las correlaciones (r), entre edad y superficie, calculadas con la totalidad de casos de cada grupo, son: 0,55 (p < 0,05) en controles y - 0,45 (p < 0,02) en esquizofrénicas. Se concluye que con el incremento de la edad en las esquizofrénicas disminuye significativamente la superficie del CC alterándose la proporcionalidad entre superficie y perímetro, mientras que en las controles el incremento de ambos permite conservar tal proporcionalidad. (AU)