MRI-based radiomic features for identifying recurrent prostate cancer after proton radiation therapy.

PURPOSE: Magnetic Resonance Imaging (MRI) evaluation of recurrent prostate cancer (PCa) following proton beam therapy is challenging due to radiation-induced tissue changes. This study aimed to evaluate MRI-based radiomic features so as to identify the recurrent PCa after proton therapy. METHODS: We retrospectively studied 12 patients with biochemical recurrence (BCR) following proton therapy. Two experienced radiologists identified prostate lesions from multi-parametric MRI (mpMRI) images post-proton therapy and marked control regions of interest (ROIs) on the contralateral side of the prostate gland. A total of 210 radiomic features were extracted from lesions and control regions on the T2-weighted (T2WI) and Apparent Diffusion Coefficient (ADC) image series. Recursive Feature Elimination with Cross-Validation method (RFE-CV) was used for feature selection. A Multilayer Perceptron (MLP) neural network was developed to classify three classes: cancerous, benign, and healthy tissue. The 12-core biopsy results were used as the gold standard for the segmentations. The classifier performance was measured using specificity, sensitivity, the area under receiver operating characteristic curve (AUC), and other statistical indicators. RESULTS: Based on biopsy results, 10 lesions were identified as PCa recurrence while eight lesions were confirmed to be benign. Ten radiomic features (10/210) were selected to build the multi-class classifier. The radiomics classifier gave an accuracy of 0.83 in identifying cancerous, benign, and healthy tissue with a sensitivity of 0.80 and specificity of 0.85. The model yielded an AUC of 0.87, 95% CI [0.72-1.00] in differentiating cancer from the benign and healthy tissues. CONCLUSIONS: Our proof-of-concept study demonstrates the potential of using radiomic features as part of the differential diagnosis of PCa on mpMRI following proton therapy. The results need to be validated in a larger cohort.

Efficient removal of triclosan from water through activated carbon adsorption and photodegradation processes.

This study investigated the application of adsorption with activated carbons (ACs) and photodegradation to reduce the concentration of triclosan (TCS) in aqueous solutions. Concerning adsorption, ACs (Darco, Norit, and F400) were characterised and batch experiments were performed to elucidate the effect of pH on equilibrium. The results showed that at pH = 7, the maximum adsorption capacity of TCS onto the ACs was 18.5 mg g-1 for Darco, 16.0 mg g-1 for Norit, and 15.5 mg g-1 for F400. The diffusional kinetic model allowed an adequate interpretation of the experimental data. The effective diffusivity varied and increased with the amount of TCS adsorbed, from 1.06 to 1.68 × 10-8 cm2 s-1. In the case of photodegradation, it was possible to ensure that the triclosan molecule was sensitive to UV light of 254 nm because the removal was over 80 % using UV light. The removal of TCS increased in the presence of sulfate radicals. It was possible to identify 2,4-dichlorophenol as one of the photolytic degradation products of triclosan, which does not represent an environmental hazard at low concentrations of triclosan in water. These results confirm that the use of AC Darco, Norit, and F400 and that photodegradation processes with UV light and persulfate radicals are effective in removing TCS from water, reaching concentration levels that do not constitute a risk to human health or environmental hazard. Both methods effectively eliminate pollutants with relatively easy techniques to implement.

Phyllotaxis transition over the lifespan of a palm tree using Magnetic Resonance Imaging (MRI) and Terrestrial Laser Scanning (TLS): the case of Jubaea chilensis.

BACKGROUND: Jubaea chilensis (Molina) Baillon, is a uniquely large palm species endemic to Chile. It is under threatened status despite its use as an ornamental species throughout the world. This research seeks to identify the phyllotaxis of the species based on an original combination of non-destructive data acquisition technologies, namely Magnetic Resonance Imaging (MRI) in saplings and young individuals and Terrestrial Laser Scanning (TLS) in standing specimens, and a novel analysis methodology. RESULTS: Two phyllotaxis parameters, parastichy pairs and divergence angle, were determined by analyzing specimens at different developmental stages. Spiral phyllotaxis patterns of J. chilensis progressed in complexity from parastichy pairs (3,2) and (3,5) in juvenile specimens and (5,3), (8,5) and (8,13) for adult specimens. Divergence angle was invariable and averaged 136.9°, close to the golden angle. Phyllotactic pattern changes associated with establishment phase, the adult vegetative and the adult reproductive phases were observed. Both technologies, MRI and TLS proved to be adequate for the proposed analysis. CONCLUSIONS: Understanding phyllotactic transitions may assist identification of developmental stages of wild J. chilensis specimens. The proposed methodology may also be useful for the study of other palm species.

Sagittal balance: from theory to clinical practice.

Adequate sagittal balance (SB) is essential to maintain an upright, efficient, and painless posture. It has been shown that sagittal profile alterations affect quality of life of patients with a similar or even greater impact than chronic disease. Evaluation of the SB has gained much relevance in recent years, with recognition of its importance in the evaluation of spinal pathology. This review summarizes the basic principles of SB, aiming to obtain a practical, simple and understandable evaluation of the sagittal profile of a patient. SB is a dynamic process that involves a varying degree of energy expenditure. Distinguishing between a balanced, compensated imbalance or decompensated imbalanced patient, is relevant to diagnosis and therapeutic decision-making.

[Identification of mycobacteria species through mass spectrometry (MALDI-TOF)]. / Identificación de especies de micobacterias mediante espectrometría de masas (MALDI-TOF).

BACKGROUND: Mycobacterial diseases are very important both clinically and epidemiologically. Mycobacterium tuberculosis complex (MTBc) infections confer higher morbidity and mortality rate than non-tuberculous mycobacteria (NTM) infections. Traditional species identification techniques are based on phenotypic characteristics which take a long time by laborious processes and in occasions are no conclusive. Currently, most used techniques are based on molecular methods, which are accurate but are expensive and complex. Matrix Assisted Laser Desorption/Ionization Time-of-Flight mass spectrometry (MALDI-TOF MS) is a simple, cheap and fast identification method based on comparing protein spectra with a reference database. AIM: To assess the performance of MALDI-TOF MS in the identification of MTBc and NTM, compared with molecular methods. METHODS: For that purpose, 28 isolates of 9 different species were analyzed through MALDI-TOF MS. RESULTS: 78.5% (22/28) of isolates were correctly identified, 100% (9/9) of rapidly growers NTM, 60% (9/15) of slow growing NTM and 100% (4/4) of MTBc. Every unidentified isolate (6/6) corresponded to M. avium/intracellulare complex. CONCLUSION: MALDI-TOF MS is fast, simple and cheaper than molecular methods and also has adequate accuracy.

Identificación de especies de micobacterias mediante espectrometría de masas (MALDI-TOF) / Identification of mycobacteria species through mass spectrometry (MALDI-TOF)

Resumen Introducción: Las enfermedades producidas por micobacterias son de gran importancia clínica y epidemiológica presentando el complejo Mycobacterium tuberculosis (MTBc) una morbi-mortalidad mayor que la producida por micobacterias no tuberculosas (MNTB). La identificación tradicional está basada en sus características fenotípicas mediante procesos laboriosos e incapaces en algunos casos de distinguir entre especies. Actualmente, la mayoría de las técnicas utilizadas se basan en métodos moleculares que tienen alta veracidad, pero son complejas y de alto costo. La espectrometría de masas con desorción/ionización láser asistida por una matriz asociada a tiempo de vuelo (MALDI-TOF MS) se basa en la comparación del espectro proteico producido con respecto al de una base de datos de referencia. Objetivo: Evaluar el rendimiento de MALDI-TOF MS en la identificación de micobacterias comparado con métodos moleculares: Material y Métodos: Se analizaron 28 aislados de nueve especies distintas mediante MALDI-TOF MS. Resultados: Se identificó correctamente 78,5% de las aislados (22/28), concordante en 100% (9/9) de MNTB de crecimiento rápido, 60% (9/15) en las MNTB de crecimiento lento y 100% (4/4) de MTBc. Todas las especies no identificadas (6/6) pertenecen al complejo M. avium/intracellulare. Conclusión: MALDI-TOD MS es una metodología rápida, fácil y de bajo costo, con adecuada veracidad respecto a los métodos moleculares.

Abstract Background: Mycobacterial diseases are very important both clinically and epidemiologically. Mycobacterium tuberculosis complex (MTBc) infections confer higher morbidity and mortality rate than non-tuberculous mycobacteria (NTM) infections. Traditional species identification techniques are based on phenotypic characteristics which take a long time by laborious processes and in occasions are no conclusive. Currently, most used techniques are based on molecular methods, which are accurate but are expensive and complex. Matrix Assisted Laser Desorption/Ionization Time-of-Flight mass spectrometry (MALDI-TOF MS) is a simple, cheap and fast identification method based on comparing protein spectra with a reference database. Aim: To assess the performance of MALDI-TOF MS in the identification of MTBc and NTM, compared with molecular methods. Methods: For that purpose, 28 isolates of 9 different species were analyzed through MALDI-TOF MS. Results: 78.5% (22/28) of isolates were correctly identified, 100% (9/9) of rapidly growers NTM, 60% (9/15) of slow growing NTM and 100% (4/4) of MTBc. Every unidentified isolate (6/6) corresponded to M. avium/intracellulare complex. Conclusion: MALDI-TOF MS is fast, simple and cheaper than molecular methods and also has adequate accuracy.

Evaluation of phytotoxic effects of cationic polyacrylamide polymers: implication for the use of sludges as organic soil amendments in assisted phytostabilization.

Sludges, as biosolids, are organic soil amendments commonly used in assisted phytostabilitation. Extensive studies on their environmental impacts exists, particularly for improper land application and contents of trace elements, organic compounds and pathogens, but not for their content of cationic polyacrylamide polymers (C-PAMs). Direct toxicity of C-PAMs on aquatic organisms has been demonstrated but scarce information about plant toxicity is available. In this study, the effect of C-PAMs on early plant growth was evaluated by means of standard toxicity assays. Firstly, increasing doses of C-PAMs were applied as solutions to seeds of Avena sativa, Lactuca sativa and Solanum lycopersycum to evaluate germination and root elongation. Secondly, the effect of increasing doses of C-PAMs spiked in pig manure and mixed with sand (75 t ha-1 dry base) was evaluated on the emergence, radicle elongation and biomass of A. sativa. Results showed high phytotoxicity of C-PAMs in solutions above 1,000 mg L-1, but no effect was detected when spiked into experimental substrate; a significant effect was only observed above 5,000 mg L-1 for radicle elongation, aerial biomass, and radicle biomass. Results demonstrate direct phytotoxic effects of C-PAMs, which can be mitigated when spiked into an organic (pig manure) and mineral (sand) matrix.

Boron stress response and accumulation potential of the extremely tolerant species Puccinellia frigida.

Phytoremediation is a promising technology to tackle boron toxicity, which restricts agricultural activities in many arid and semi-arid areas. Puccinellia frigida is a perennial grass that was reported to hyperaccumulate boron in extremely boron-contaminated sites. To further investigate its potential for phytoremediation, we determined its response to boron stress under controlled conditions (hydroponic culture). Also, as a first step towards understanding the mechanisms underlying its extreme tolerance, we evaluated the presence and expression of genes related with boron tolerance. We found that P. frigida grew normally even at highly toxic boron concentrations in the medium (500mg/L), and within its tissues (>5000mg/kg DW). We postulate that the strategies conferring this extreme tolerance involve both restricting boron accumulation and an internal tolerance mechanism; this is consistent with the identification of putative genes involved in both mechanisms, including the expression of a possible boron efflux transporter. We also found that P. frigida hyperaccumulated boron over a wide range of boron concentrations. We propose that P. frigida could be used for boron phytoremediation strategies in places with different soil characteristics and boron concentrations. Further studies should pave the way for the development of clean and low-cost solutions to boron toxicity problems.

Sectional anatomic and magnetic resonance imaging features of the head of juvenile loggerhead sea turtles (Caretta caretta).

OBJECTIVE: To compare anatomic features of cross-sectional specimens with those of MRI images of the heads of loggerhead sea turtles (Caretta caretta). ANIMALS: 5 cadavers of juvenile female loggerhead sea turtles. PROCEDURES: Spin-echo T1-weighted and T2-weighted MRI scans were obtained in sagittal, transverse, and dorsal planes with a 0.2-T magnet and head coil. Head specimens were grossly dissected and photographed. Anatomic features of the MRI images were compared with those of gross anatomic sections of the heads from 4 of these turtles. RESULTS: In the MRI images, anatomic details of the turtles' heads were identified by the characteristics of signal intensity of various tissues. Relevant anatomic structures were identified and labeled on the MRI images and corresponding anatomic sections. CONCLUSIONS AND CLINICAL RELEVANCE: The MRI images obtained through this study provided valid information on anatomic characteristics of the head in juvenile loggerhead sea turtles and should be useful for guiding clinical evaluation of this anatomic region in this species.

Fractions of aqueous and methanolic extracts from tomato (Solanum lycopersicum L.) present platelet antiaggregant activity.

Cardiovascular disease (CVD) is the leading cause of death worldwide. Its prevention emphasizes three aspects: not smoking, physical activity and a healthy diet. Recently, we screened the antithrombotic activity of a selected group of fruits and vegetables. Among them, tomato showed an important effect. The aim of this study was to evaluate and characterize the platelet antiaggregatory activity of tomato (Solanum lycopersicum L.). For this, we obtained aqueous and methanolic tomato extracts and evaluated the effect of pH (2 and 10) and temperature (22, 60 and 100°C) on this activity. Furthermore, in order to isolate the antiaggregant principle, we separated tomato extracts into several fractions (A-D) by size exclusion chromatography. In addition, we evaluated the platelet antiaggregating activity ex vivo in Wistar rats. Aqueous and methanolic extracts of tomato treated at 22, 60 and 100°C and pH 2 and 10 still inhibited platelet aggregation (in vitro). Moreover, it was noted that one of the fractions (fraction C), from both aqueous and methanolic extracts, presented the highest activity (∼70% inhibition of platelet aggregation) and concentration dependently inhibited platelet aggregation significantly compared with control (P < 0.05). These fractions did not contain lycopene but presented two peaks of absorption, at 210 and 261 nm, compatible with the presence of nucleosides. In rats treated with tomato macerates, a mild platelet antiaggregating effect ex vivo was observed. Further studies are required to identify the molecules with platelet antiaggregating activity and antiplatelet mechanisms of action.

Black and bright-blood sequences magnetic resonance angiography and gross sections of the canine thorax: an anatomical study.

In this study, images of the canine thorax in transverse, dorsal and sagittal planes were obtained by black-blood T1 spin-echo pulse sequence and bright-blood gradient-echo sequence magnetic resonance imaging. The images were correlated with macroscopic cryosections and anatomical dissection of cadavers with blood vessels containing latex. Non-contrast-enhanced magnetic resonance angiography was obtained from two mature Beagle breed dogs. Macroscopic sections and dissections were performed in three dogs. Black and bright-blood angiography diagnostic methods are complementary and provide an accurate depiction of the vascular canine thorax.

Resección de hemivértebra con técnica de eggshell en cifoescoliosis congénita: resultados en niños entre uno y siete años / Ressecção de hemivertébra com a técnica de eggshell em cifoescoliose congênita: resultados em crianças com idade entre um e sete anos / Hemivertebrae resection with eggshell procedure for congenital kyphoscoliosis: results in children aged from one to seven years

INTRODUCCIÓN: La hemivértebra es la causa de 50 por ciento de las cifoescoliosis congénitas y en general requiere tratamiento quirúrgico. OBJETIVO: evaluar los resultados clínicos y radiológicos de la resección de hemivértebra con técnica de eggshell en niños entre uno y siete años. DISEÑO DEL ESTUDIO: análisis retrospectivo de pacientes sometidos a resección de hemivértebra con técnica de eggshell. MÉTODOS: entre Enero del 2006 y Junio del 2008, siete hemivértebras fueron resecadas en siete pacientes consecutivos, entre uno y siete años de edad. Se revisó retrospectivamente las fichas clínicas y radiografías. La edad promedio al momento de la cirugía fue 3,2 años (rango de uno a siete años) y el seguimiento promedio fue de 17 meses (rango 7 a 35 meses). Se registró ángulo de Cobb de la escoliosis y cifosis en el preoperatorio y al término del seguimiento, tiempo operatorio, transfusión de glóbulos rojos y complicaciones. RESULTADOS: el ángulo preoperatorio promedio de la escoliosis fue 35º y 19º al término del seguimiento, con un 40 por ciento de corrección. El ángulo preoperatorio promedio de la cifosis fue 42º y 25º al término del seguimiento, con un 33 por ciento de corrección. Cuatro pacientes necesitaron transfusión de glóbulos rojos, promedio 1,25 unidades. El tiempo quirúrgico promedio fue 225 minutos. Dos pacientes presentaron complicaciones, una rotura dural y una fractura pedicular. No se presentaron complicaciones neurológicas. Todos los pacientes presentaban fusión sólida al término del seguimiento. CONCLUSIÓN: la resección de hemivértebra con técnica de eggshell es un procedimiento seguro, que permite una excelente e inmediata corrección de la cifoescoliosis congénita, la que se mantiene en el corto plazo.

INTRODUÇÃO: A hemivértebra associa-se a 50 por cento das cifoescolioses congênitas e geralmente requer tratamento cirúrgico. OBJETIVO: avaliar os resultados clínicos e radiológicos da ressecção da hemivértebra, utilizando a técnica de eggshell em crianças entre um e sete anos. FORMA DO ESTUDO: análise retrospectiva dos pacientes submetidos à ressecção de hemivértebra com a técnica eggshell. MÉTODOS: Entre Janeiro de 2006 e Junho de 2008, sete hemivértebras foram ressecadas em sete pacientes consecutivos, entre um e sete anos de idade. Realizou-se análise retrospectiva dos prontuários e exames radiográficos. A média de idade no momento da cirurgia foi de 3,2 anos (variação entre um a sete anos) e o seguimento médio foi de 17 meses (variação de 7 a 35 meses). Registrou-se ângulo de Cobb na escoliose e cifose no pré-operatório e no término do seguimento, o tempo operatório, transfusão de glóbulos vermelhos e complicações. RESULTADOS: o ângulo pré-operatório médio da escoliose foi de 35º e 19º no término do seguimento, com um 40 por cento de correção. O ângulo pré-operatório médio da cifose foi de 42º e 25º no término do seguimento, com 33 por cento de correção. Quatro pacientes precisaram de transfusão de glóbulos vermelhos, 1,25 unidades como média. O tempo cirúrgico médio foi de 225 minutos. Dois pacientes apresentaram complicações, uma rotura dural e uma fratura pedicular. Não houve complicações neurológicas. Todos os pacientes apresentaram sólida fusão no término do seguimento. CONCLUSÃO: a ressecção de hemivértebra utilizando a técnica de eggshell é um procedimento seguro que permite uma excelente e imediata correção da cifoescoliose congênita, a qual é mantida no curto prazo.

INTRODUCTION: Hemivertebrae is associated with 50 percent of the congenital kyphoscoliosis and surgical treatment is usually required. OBJECTIVE: to evaluate clinical and radiographic results of hemivertebra resection with an eggshell procedure in children aged from one to seven years old. STUDY DESIGN: retrospective review of patients who underwent hemivertebrae resection with an eggshell procedure. METHODS: from January 2006 to June 2008, seven hemivertebrae were resected in seven consecutive patients aged one to seven years old. A retrospective chart and a radiographic review were performed. The mean age at surgery was 3,2 years (range from one to seven years). The mean follow-up was 17 months (range from 7 to 35 months). Cobb's angle in the coronal and sagittal planes preoperative and at follow-up, operating time, transfusion requirements and complications were analyzed. RESULTS: the mean pre-operative scoliosis Cobb's angle was 35º and the average at follow-up was 19º. The mean correction at follow-up was 40 percent. The average of the pre-operative kyphosis Cobb's angle was 42º and average at follow-up was 25º. Rate of correction at follow-up was 33 percent. Four patients required transfusion, with an average of 1,25 blood units. The average of operating time was 225 minutes. Complications were encountered in two patients; one dural tear and one pedicular fracture. No neurological complications. All patients achieved solid fusion at follow-up. CONCLUSION: hemivertebra resection with the eggshell procedure is a safe surgical technique and provides an excellent and immediate correction of congenital kyphoscoliosis at short term follow-up.

Magnetic resonance angiography of the normal canine heart and associated blood vessels.

Magnetic resonance angiography (MRA) images of the normal canine heart and associated blood vessels were obtained from two mature Beagle dogs. Fast spin-echo sequence MRA images were taken with a 1.5T magnet and a human thorax coil. Relevant vascular structures were identified and labelled on maximum intensity projection reconstructions of 3D gadolinium-enhanced MRA and anatomical dissections with vascular latex injection taken from the right and the left thoracic walls and the base of the heart. These images should provide useful reference material for clinical studies of the canine heart.