Assessment of the abdominal aorta and its visceral branches by contrast-enhanced dynamic volumetric hepatic parallel magnetic resonance imaging: feasibility, reliability and accuracy

The purpose of this study was to evaluate a new three-dimensional gradient-echo (GRE) MR sequence performed with a parallel acquisition technique to shorten breath-hold times (parallel GRE MRI) in the detection of arterial variants and stenosis of the abdominal aorta and its visceral branches. A total of 102 patients underwent dynamic parallel GRE MRI, timed to the arterial phase by a test bolus (mean breath-hold time, 17s). For both quantitative and qualitative analysis, the abdominal aorta and its visceral branches were divided into 13 arterial segments. In a subanalysis of 55/102 patients, the accuracy of parallel GRE MRI compared to MDCT in the detection arterial variants and stenosis was calculated for two independent readers. Mean SNRs and CNRs were 47.2 and 35.6, respectively. Image quality was rated good or excellent in 1,234/1,326 segments (93%). Hepatic and renal arterial variants were identified with an accuracy of 93 and 95%, respectively (reader 1) and 98 and 100%, respectively (reader 2). Both readers detected arterial stenosis with an accuracy of 98%. Interobserver agreement was good to excellent for the detection of hepatic (κ=0.69) and renal (κ=0.92) variants and for the diagnosis of stenosis (κ=0.96). Dynamic three-dimensional parallel GRE MRI is feasible and allows a reliable and accurate diagnosis of arterial variants and stenosis of the abdominal aorta and its visceral branches in a short breath-hold-tim

Prospective intraindividual comparison between respiratory-triggered balanced steady-state free precession and breath-hold gradient-echo and time-of-flight magnetic resonance imaging for assessment of portal and hepatic veins

The purpose of this study was to compare respiratory-triggered balanced steady-state free precession (bSSFP) with breath-hold contrast-enhanced dynamic two-dimensional (2D) gradient-echo (GRE) and time-of-flight (TOF) magnetic resonance imaging (MRI) for portal and hepatic vein visualization and assessment of portal and hepatic venous variants. Sixty patients with liver disease underwent nonenhanced bSSFP and contrast-enhanced GRE, bSSFP, and TOF imaging. Contrast-to-noise ratios (CNRs) for portal and hepatic veins were measured. Two readers rated the quality of portal and hepatic vein visualization on a 5-point Likert scale. The diagnostic performance of each MRI series in the detection of portal and hepatic venous variants was assessed in 40/60 patients who also underwent contrast-enhanced multidetector-row computed tomography (MDCT). CNRs for portal and hepatic veins were highest on contrast-enhanced bSSFP images. Image quality of portal and hepatic veins was rated higher for nonenhanced bSSFP than for contrast-enhanced GRE (p<0.03) and TOF (p<0.003) and higher for contrast-enhanced than for nonenhanced bSSFP (p<0.003). Compared with MDCT, portal and hepatic venous variants were identified with an accuracy of 99% on bSSFP images, with an excellent interobserver agreement (κ=0.97). Compared with MDCT, presence of surgically important portal and hepatic venous anatomical variants can be predicted with high accuracy on bSSFP image

The Argentine experience with human immune deficiency virus positive patients in the waiting list for liver transplantation: preliminary analysis

Previamente, la seropositividad para el virus de la inmunodeficiencia humana (HIV) era una contraindicación absoluta del trasplante. Sin embargo, reportes de la época posterior al tratamiento antirretroviral altamente activo (HAART) demostraron que los resultados no se diferenciarían de la población HIV negativa. Objetivo. Evaluar la experiencia en Argentina con pacientes HIV positivos incluidos en lista para trasplante hepático. Pacientes y métodos. Se incluyeron 52 pacientes HIV positivos ingresados en lista del 12 de julio de 2005 al 31 de marzo de 2010. Los resultados se compararon con 462 pacientes HIV negativos incluidos en lista durante el mismo período. Los datos se obtuvieron del SINTRA y centros intervinientes. Resultados. La etiología de hepatopatía en el grupo HIV positivo fue: hepatitis C en 40 pacientes, hepatitis B en 3, hepatitis fulminante en 3, alcohol en 2, retrasplante en 2 y otras en 2. El MELD promedio del grupo HIV positivo al ingreso en la lista fue 16,15 (menor de 19 en 40 pacientes, mayor de 19 en 8 y emergencia en 3) y el del grupo HIV negativo fue 16,64 (NS). La evolución en lista de espera para los pacientes HIV positivos y negativos fue respectivamente: muerte en lista 14 pacientes (27%) vs 61 (18,7%) (P < 0,05), trasplante con donante cadavérico 10 (13%) vs 95 (29,4%) (P < 0,01), trasplante con donante vivo 0 (0%) vs 5 (1,1%) (NS), tiempo medio desde el ingreso en lista a la muerte 270,70±298,11 días vs 267,29±266,53 días (NS), tiempo medio en la lista hasta el trasplante 70,26±74,05 vs 261±187,6 días (P < 0,01), MELD medio al fallecimiento 12,54 (13 casos menor de 15, 1 mayor de 19) vs 19,6±9,7 (P < 0,05), y MELD medio al momento del trasplante 24,33 vs 24,1±7,6 (NS). Conclusión. Los resultados del trasplante en pacientes HIV positivos son buenos. Sin embargo, presentan muy alta mortalidad en lista de espera que no correlaciona con su gravedad medida por el score de MELD. Quienes acceden al trasplante lo hacen rápidamente en el contexto de una descompensación, por hepatitis fulminante o por retrasplante.After the introduction of high active antiretroviral therapy (HAART), the human immunodeficiency virus (HIV) was no longer considered a contraindication for transplantation. Yet, liver disease in this population is characterized by an accelerated course that may impact on the waiting list. Objective. To evaluate the experience in Argentina with HIV positive patients listed for liver transplantation. Patients and methods. We analyzed 52 HIV positive patients listed between July 2005 and March 2010 (Group HIV positive). Results were compared with 462 HIV negative patients included during the same period (Group HIV negative). Data were obtained from INCUCAI, the Argentinian procurement organism and from the Transplantation Centers. Results. The etiology of liver disease in the Group HIV positive was hepatitis C 40, HBV 3, fulminant hepatitis 3, alcohol 2, retrasplant 2 and others 2. The mean MELD at the time of listing was 16.15 (lower than 19 in 40 cases, higher than 19 in 8, emergency in 3) in the group HIV positive and 16.64 in the group HIV negative (NS). The outcome in the waiting list for HIV positive and negative patients respectively was: death 14 (27%) vs 61 (18.7%) (P < 0.05), cadaveric donor transplant 10 (13%) vs 95 (29.4%) (P < 0.001), living donor transplant 0 (0%) vs 5 (1.1%) (NS), mean time from listing to death 270.70 298.11 days vs 267.29 266.53 days (NS), mean time from listing to transplant 70.26 74.05 vs 261 187.6 days (P < 0.01), mean MELD at the time of death 12.54 (13 cases lower than 15, 1 higher than 19) vs 19.6 9.7 (P < 0.05), mean MELD at the time of transplantation 24.33 vs 24.1 7.6 (NS). Conclusion. HIV positive patients have high mortality in the waiting list and low access to liver transplantation. MELD score underscores the severity of liver disease in this population when compared to HIV negative patients.Fil: Villamil, Alejandra. Hospital Italiano; ArgentinaFil: Bisignano, Liliana. Incucai; ArgentinaFil: Orozco, Federico. Hospital Italiano de la Plata; ArgentinaFil: Bandi, Juan Carlos. Hospital Italiano de la Plata; ArgentinaFil: Barcán, Laura. Hospital Italiano de la Plata; ArgentinaFil: McCormack, Lucas. Hospital Alemán; ArgentinaFil: Gondolesi, Gabriel Eduardo. Fundación Favaloro; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: de Santibañes, Eduardo. Hospital Italiano de la Plata; ArgentinaFil: Gadano, Adrián. Hospital Italiano de la Plata; Argentin

In-service Initial Teacher Education in the Learning and Skills Sector in England: Integrating Course and Workplace Learning

The aim of the paper is to advance understanding of in-service learning and skills sector trainee teachers’ learning and propose ways of improving their learning. A conceptual framework is developed by extending Billett’s (International Journal of Educational Research 47:232–240, 2008) conceptualisation of workplace learning, as a relationally interdependent process between the opportunities workplaces afford for activities and interactions and how individuals engage with these, to a third base of participation, the affordances of the initial teacher education course. Hager and Hodkinson’s (British Educational Research Journal 35:619–638, 2009) metaphor of ‘learning as becoming’ is used to conceptualise the ways trainees reconstruct learning in a continuous transactional process of boundary crossing between course and workplace. The findings of six longitudinal case studies of trainees’ development, and evidence from other studies, illustrate the complex interrelationships between LSS workplace affordances, course affordances and trainee characteristics and the ways in which trainees reconstruct learning in each setting. The experience of teaching and interacting with learners, interactions with colleagues, and access to workplace resources and training are important workplace affordances for learning. However, some trainees have limited access to these affordances. Teaching observations, course activities and experiences as a learner are significant course affordances. Trainees’ beliefs, prior experiences and dispositions vary and significantly influence their engagement with course and workplace affordances. It is proposed that better integration of course and workplace learning through guided participation in an intentional workplace curriculum and attention to the ways trainees choose to engage with this, together with the use of practical theorising has the potential to improve trainee learning

Predicting the HMA-LMA status in marine sponges by machine learning

The dichotomy between high microbial abundance (HMA) and low microbial abundance (LMA) sponges has been observed in sponge-microbe symbiosis, although the extent of this pattern remains poorly unknown. We characterized the differences between the microbiomes of HMA (n=19) and LMA (n=17) sponges (575 specimens) present in the Sponge Microbiome Project. HMA sponges were associated with richer and more diverse microbiomes than LMA sponges, as indicated by the comparison of alpha diversity metrics. Microbial community structures differed between HMA and LMA sponges considering Operational Taxonomic Units (OTU) abundances and across microbial taxonomic levels, from phylum to species. The largest proportion of microbiome variation was explained by the host identity. Several phyla, classes, and OTUs were found differentially abundant in either group, which were considered “HMA indicators” and “LMA indicators”. Machine learning algorithms (classifiers) were trained to predict the HMA-LMA status of sponges. Among nine different classifiers, higher performances were achieved by Random Forest trained with phylum and class abundances. Random Forest with optimized parameters predicted the HMA-LMA status of additional 135 sponge species (1,232 specimens) without a priori knowledge. These sponges were grouped in four clusters, from which the largest two were composed of species consistently predicted as HMA (n=44) and LMA (n=74). In summary, our analyses shown distinct features of the microbial communities associated with HMA and LMA sponges. The prediction of the HMA-LMA status based on the microbiome profiles of sponges demonstrates the application of machine learning to explore patterns of host-associated microbial communities

Fatty liver disease, an emerging etiology of hepatocellular carcinoma in Argentina

AIM To investigate any changing trends in the etiologies of hepatocellular carcinoma (HCC) in Argentina during the last years. METHODS A longitudinal cohort study was conducted by 14 regional hospitals starting in 2009 through 2016. All adult patients with newly diagnosed HCC either with pathology or imaging criteria were included. Patients were classified as presenting non-alcoholic fatty liver disease (NAFLD) either by histology or clinically, provided that all other etiologies of liver disease were ruled out, fatty liver was present on abdominal ultrasound and alcohol consumption was excluded. Complete follow-up was assessed in all included subjects since the date of HCC diagnosis until death or last medical visit. RESULTS A total of 708 consecutive adults with HCC were included. Six out of 14 hospitals were liver transplant centers (n = 484). The prevalence of diabetes mellitus was 27.7%. Overall, HCV was the main cause of liver disease related with HCC (37%) including cirrhotic and non-cirrhotic patients, followed by alcoholic liver disease 20.8%, NAFLD 11.4%, cryptogenic 9.6%, HBV 5.4% infection, cholestatic disease and autoimmune hepatitis 2.2%, and other causes 9.9%. A 6-fold increase in the percentage corresponding to NAFLDHCC was detected when the starting year, i.e., 2009 was compared to the last one, i.e., 2015 (4.3% vs 25.6%; P < 0.0001). Accordingly, a higher prevalence of diabetes mellitus was present in NAFLD-HCC group 61.7% when compared to other than NAFLD-HCC 23.3% (P < 0.0001). Lower median AFP values at HCC diagnosis were observed between NAFLD-HCC and non-NAFLD groups (6.6 ng/mL vs 26 ng/mL; P = 0.02). Neither NAFLD nor other HCC etiologies were associated with higher mortality. CONCLUSION The growing incidence of NAFLD-HCC documented in the United States and Europe is also observed in Argentina, a confirmation with important Public Health implications.Fil: Piñero, Federico. Hospital Universitario Austral; Argentina. Sanatorio de la Trinidad San Isidro; ArgentinaFil: Pages, Josefina. Hospital Universitario Austral; ArgentinaFil: Marciano, Sebastián. Hospital Italiano; ArgentinaFil: Fernández, Nora. Hospital Británico de Buenos Aires; ArgentinaFil: Silva, Jorge. Provincia de San Juan. Hospital Rawson; ArgentinaFil: Anders, Margarita. Hospital Alemán; ArgentinaFil: Zerega, Alina. Sanatorio Allende; ArgentinaFil: Ridruejo, Ezequiel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. CEMIC-CONICET. Centro de Educaciones Médicas e Investigaciones Clínicas "Norberto Quirno". CEMIC-CONICET; ArgentinaFil: Ameigeiras, Beatriz. Gobierno de la Ciudad de Buenos Aires. Hospital General de Agudos "Ramos Mejía"; ArgentinaFil: D'amico, Claudia. Centro Especialidades Médicas Ambulatorias Mar del Plata; ArgentinaFil: Gaite, Luis. Clínica de Nefrología de Santa Fe; ArgentinaFil: Bermúdez, Carla. Hospital Italiano; ArgentinaFil: Cobos, Manuel. Hospital Alemán; ArgentinaFil: Rosales, Carlos. Provincia de San Juan. Hospital Rawson; ArgentinaFil: Romero, Gustavo. Gobierno de la Ciudad de Buenos Aires. Hospital de Gastroenterología "Dr. Carlos B. Udaondo"; ArgentinaFil: McCormack, Lucas. Hospital Alemán; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Reggiardo, Virginia. Gobierno de Santa Fe. Hospital Provincial del Centenario; ArgentinaFil: Colombato, Luis. Hospital Británico de Buenos Aires; ArgentinaFil: Gadano, Adrián Carlos. Hospital Italiano; ArgentinaFil: Silva, Marcelo. Hospital Universitario Austral; Argentin

Quantitative Assessment of Mammary Gland Density in Rodents Using Digital Image Analysis

<p>Abstract</p> <p>Background</p> <p>Rodent models have been used extensively to study mammary gland development and for studies of toxicology and carcinogenesis. Mammary gland gross morphology can visualized via the excision of intact mammary gland chains following fixation and staining with carmine using a tissue preparation referred to as a whole mount. Methods are described for the automated collection of digital images from an entire mammary gland whole mount and for the interrogation of digital data using a "masking" technique available with Image-Pro^®plus image analysis software (Mediacybernetics. Silver Spring, MD).</p> <p>Results</p> <p>Parallel to mammographic analysis in humans, measurements of rodent mammary gland density were derived from area-based or volume-based algorithms and included: total circumscribed mammary fat pad mass, mammary epithelial mass, and epithelium-free fat pad mass. These values permitted estimation of absolute mass of mammary epithelium as well as breast density. The biological plausibility of these measurements was evaluated in mammary whole mounts from rats and mice. During mammary gland development, absolute epithelial mass increased linearly without significant changes in mammographic density. Treatment of rodents with tamoxifen, 9-cis-retinoic acid, or ovariectomy, and occurrence of diet induced obesity decreased both absolute epithelial mass and mammographic density. The area and volumetric methods gave similar results.</p> <p>Conclusions</p> <p>Digital image analysis can be used for screening agents for potential impact on reproductive toxicity or carcinogenesis as well as for mechanistic studies, particularly for cumulative effects on mammary epithelial mass as well as translational studies of mechanisms that explain the relationship between epithelial mass and cancer risk.</p

A calmodulin-like protein regulates plasmodesmal closure during bacterial immune responses

Plants sense microbial signatures via activation of pattern recognition receptors (PPRs), which trigger a range of cellular defences. One response is the closure of plasmodesmata, which reduces symplastic connectivity and the capacity for direct molecular exchange between host cells. Plasmodesmal flux is regulated by a variety of environmental cues but the downstream signalling pathways are poorly defined, especially the way in which calcium regulates plasmodesmal closure. Here, we identify that closure of plasmodesmata in response to bacterial flagellin, but not fungal chitin, is mediated by a plasmodesmal-localized Ca2+ -binding protein Calmodulin-like 41 (CML41). CML41 is transcriptionally upregulated by flg22 and facilitates rapid callose deposition at plasmodesmata following flg22 treatment. CML41 acts independently of other defence responses triggered by flg22 perception and reduces bacterial infection. We propose that CML41 enables Ca2+ -signalling specificity during bacterial pathogen attack and is required for a complete defence response against Pseudomonas syringae.Bo Xu, Cecilia Cheval, Anuphon Laohavisit, Bradleigh Hocking, David Chiasson, Tjelvar S. G. Olsson, Ken Shirasu, Christine Faulkner and Matthew Gilliha

Pathways to fatherhood: psychological well-being among Israeli gay fathers through surrogacy, gay fathers through previous heterosexual relationships, and heterosexual fathers

This study explored differences in psychological well-being as assessed by life satisfaction, parenthood satisfaction, depressive symptoms and the Big Five personality dimensions among 219 Israeli fathers; 76 gay men who had become fathers through a heterosexual relationship, 63 gay men who had become fathers through surrogacy, and 78 heterosexual men. After controlling for sociodemographic characteristics, gay fathers through surrogacy reported greater satisfaction with parenthood, greater satisfaction with their lives, and reported higher levels of extraversion when compared to heterosexual fathers. No significant differences emerged between the three groups on depressive symptoms, neuroticism, conscientiousness, agreeableness, and openness to experience. These findings emphasize the predominant similarities and some possible differences on psychological well-being between the different paths to fatherhood. This study is one of the first to compare several paths to fatherhood on psychological well-being, thus illuminating the contribution of fatherhood route to psychological well-being in an era where gay men are increasingly becoming fathers in diverse ways