Ewe's diet during gestation and lactation affects ready-to-eat meat from light lambs.

Maternal grazing may benefit the fatty acid (FA) profile of lamb meat, although any improvement in terms of healthier polyunsaturated FAs (PUFA) may be impaired during subsequent culinary treatments. The objective was to assess the effects of a grass-based ewe diet on the FA profile of the ready-to-eat meat from grain-fed Segureña light lamb. The FA were determined in raw, grilled (G), Sous Vide (SV) cooked and cooked/hot-held (H) lamb leg patties resulting from two maternal rearing systems: grazing (Mediterranean trees, shrubs, herbs, stubble and fallow) or indoors (cereal grain and lucerne pellets). The grass-based ewe diet increased (P < 0.05) levels of n-3 PUFA and total linoleic conjugated acid (CLA), and decreased those of n-6 long chain PUFA and saturated FA (SFA) in the patties from all treatments. These changes in FA slightly increased (P < 0.05) the PUFA/SFA ratio and decreased (P < 0.05) the n-6/n-3 ratio in the raw (from 8.7 to 6.3), SV (from 8.8 to 6.2), G (from 9.0 to 6.3), SV + H (from 8.2 to 6.3) and G + H (from 9.3 to 6.4) patties, improving the atherogenic, thrombogenic and saturation indexes. The effects of the ewe's diet on lamb FA remained unaltered after successive culinary treatments, including aerobically mincing, cooking at an internal temperature of 72 °C and H at 65 °C for 4 h. Heating induced a partial degradation of meat PUFA but also favoured the loss of high saturated melted fat. Both facts balanced the PUFA/SFA ratio in cooked lamb despite the gradual formation of oxidised secondary lipids to the detriment of FA. Grilling or SV cooking did not affect the remaining levels of undegraded FA in the freshly cooked lamb, although SV improved the results obtained for the cooked/H lamb. Maternal diets based on grass result in a healthier ready-to-eat lamb.

Effects of sous vide vs grilling methods on lamb meat colour and lipid stability during cooking and heated display.

The present study compared the effect of grilling (150 °C until 72 °C core temperature) and sous-vide (SV) cooking (75 °C for 35 min in a water bath under vacuum) on lamb patties immediately after cooking and after 4 h display at 65 °C. Both methods produced patties with similar (P > 0.05) weight loss, and moisture and fat contents. SV-cooking prevented (P < 0.05) the formation of thiobarbituric acid reactive substances (TBARS) and oxysterols compared to grilled patties, which showed a larger proportion of highly peroxidisable polyunsaturated fatty acids. Heated display induced dehydration, surface darkening and a reduction in the hexanal/3-methylbutanal ratio, suggesting the progression of Maillard reactions. Moreover, TBARS and some lipid oxidation-derived volatiles increased (P < 0.001), while cooked-meat aroma compounds were reduced (P < 0.001). SV-cooking inhibited (P < 0.05) the formation of malondialdehyde, and 7α- and 7ß-hydroxycholesterol, and lowered the cholesterol oxidation ratio during heated display. Overall, SV-cooking may be considered a healthier way of cooking when lamb meat is to be kept warm for considerable periods before consumption.

Drug Challenge Tests With General Anesthetics: Predictive Value of Skin Tests.

BACKGROUND: The study of perioperative drug reactions remains a major challenge for both diagnosis and therapy. The lack of a standard assessment of allergy to general anesthetics and of data establishing the true value of skin tests for most drugs used in induction and maintenance of anesthesia, as well as the lack of commercially available reagents for in vitro tests, renders the study of these reactions problematic. The aims of this study were to provide a diagnostic protocol for drug challenge testing with general anesthetics, to establish an etiological diagnosis that is as specific as possible, and to determine the predictive value of skin tests. METHODS: Twenty-nine patients with perioperative drug reactions were included in the study from November 2008 to December 2018. RESULTS: We confirmed the high negative predictive value of the tests (96%-100%) in the case of propofol, rocuronium, and fentanyl. To our knowledge, this is the first study to describe drug challenge testing with general anesthetics and, therefore, to establish the true negative predictive value of skin tests, which leads to a definitive diagnosis and safer surgery. CONCLUSIONS: After assessing risks and benefits and considering the importance of this group of drugs, we conclude that drug challenge testing with general anesthetics is necessary. We propose a protocol for perioperative drug reactions that enables us to make a highly accurate etiological diagnosis with minimum risk for the patient.

Maternal grazing on stubble and Mediterranean shrubland improves meat lipid profile in light lambs fed on concentrates.

Concentrates-fed lamb meat is often associated with an unfavourable lipid profile (high levels of saturated and/or n-6 polyunsaturated fatty acids; SFA and PUFA). For this reason, Spanish sheep producers from Mediterranean areas are turning to traditional grazing by ewes to obtain healthier lamb meat. The objective of this research was to determine the effects of maternal grazing on the fatty acid (FA) composition of weaned lamb meat. The ewes (Segureña breed) were allocated to two different rearing systems during pregnancy (5 months) and lactation (45 days): (i) feeding indoors on barley grain and lucerne pellets; (ii) grazing on cereal stubble, fallow land and seasonal pastures consisting of Mediterranean shrubs, herbs and trees. Two groups of 20 autumn and spring lambs were sampled. The lambs were weaned at 13.1±0.9 kg and 45.0±4.1 days age and fed on grain-based concentrates until they reached 24.8±2.1 kg live weight (light lambs slaughtered at 98.3±3.6 days of age). The FA content was determined in the intramuscular loin fat by gas chromatography using a flame ionization detector. The ewe diet did not affect the levels of the main lamb FAs (C18:1c+t, C16:0 and C18:2c), and so did not provide any additional reduction in fat saturation. Saturated fatty acids represented around 40% of total FAs determined in the meat. Ewe grazing acted as an n-3 PUFA-promoting diet, providing a lamb meat with a lower n-6/n-3 ratio. Spring lamb meat had higher proportions of n-3 PUFA (C18:3n-3, C20:5, C22:5 and C22:6) and conjugated linoleic acid (C18:2c9t11+c11t9) to the detriment of the n-6 PUFAs (C20:4, C20:2 and C22:4), while autumn lamb meat also had higher levels of C18:3n-3 and C18:3n-6, and lower level of C20:4, which points to little seasonal differences. The n-6/n-3 ratio achieved by ewe grazing fell from 8.2 to 4.1 (Spring) and from 7.6 to 5.5 (Autumn), values which are close to those recommended in human diet for good cardiovascular health. These n-6/n-3 reductions were associated with lower levels of total PUFA and C20:4n-6. Our research concluded that grazing on stubble and Mediterranean shrubland by ewes, a sustainable rearing practice involving local agro resources, contributed to obtaining weaned lamb meat with a more favourable lipid profile and so can be recommended to sheep farmers.

Use of dietary rosemary diterpenes to inhibit rancid volatiles in lamb meat packed under protective atmosphere.

The objective of the present study was to determine the inhibitory effect of dietary rosemary diterpenes on the formation of the volatile organic compounds (VOCs) responsible for rancid flavour in raw lamb meat. The lamb diet was supplemented during the fattening stage with two levels (200 and 400 mg/kg feed) of a dietary rosemary extract (DRE) containing carnosic acid and carnosol (1 : 1, w/w). The formation of VOCs (determined by headspace solid-phase microextraction at 40°C and MS) and odour deterioration (assessed by quantitative descriptive analysis) were monitored in meat fillets (longissimus dorsi-lumborum muscle) packed in a 70/30 O2/CO2 protective atmosphere and kept at 2°C for up to 14 days. The raw meat odour deteriorated under pro-oxidizing conditions due to the development of an incipient rancidity caused by the formation of volatiles from lipid oxidation. A total of 46 volatile compounds were determined in lamb headspace: 18 aldehydes, seven alcohols, seven organic acids, six ketones, four furan compounds, two benzene compounds, one ester and one terpenoid. The use of DRE contributed to inhibit VOC formation and rancidity. Heptanal, octanal, nonanal and 2-pentyl-furan were the only VOCs affected (P0.75; P<0.001), although similar values were obtained for the coefficients of a large number of carbonyl, alcohols and furan compounds, among other volatiles, which can be considered molecular markers of rancidity in raw lamb meat. Principal component analysis confirmed that the differences in the VOC profile make it possible to identify whether or not samples have been reinforced with dietary rosemary diterpenes. Thus, VOC profiling can be regarded as a useful tool for assessing the dietary treatments used in sheep to improve the oxidative stability of lamb meat.

Factores asociados al inicio de la lactancia materna y razones de la madre para la toma de su decisión / Predictors of breastfeeding initiation and maternal reasons for this decision

Introducción: Los beneficios de la lactancia materna (LM) son bien conocidos. En estudios previos se constata que aproximadamente un 20% de las madres deciden no iniciarla. Existe un escaso conocimiento de los factores que predicen tal decisión y los motivos maternos para ello. En este estudio analizamos la prevalencia de inicio de la LM, los factores asociados y las razones maternas al respecto. Método: Estudio de prevalencia de inicio de la LM de gestaciones ≥ 36 semanas. Recogida de variables mediante encuestas presenciales en las primeras 24 horas posparto. Estudio multivariante de los factores asociados al inicio de la LM. Resultados: Se estudió un total de 452 pares, madre-recién nacido. El 81% inició la LM. Los factores favorecedores fueron la opinión favorable de la pareja (odds ratio [OR]= 28,49; intervalo de confianza [IC] del 95%: 5,34-151,95), la opinión neutral de la abuela materna (OR= 4,79; IC del 95%: 0,99-23,76), haber dado LM al hijo previo (OR= 22,63; IC del 95%: 5,68-90,07) y residir en la misma provincia donde está ubicado el hospital (OR= 47,34; IC del 95%: 16,09-139,31). Los factores desfavorecedores fueron: el hábito tabáquico de la madre (OR= 0,37; IC del 95%: 0,15-0,92), haber tenido abortos previos (OR= 0,35; IC del 95%: 0,20-0,60) y precisar tratamiento farmacológico al iniciar la lactancia (OR= 0,25; IC del 95%: 0,08-0,74). Conclusiones: Aportamos ciertos factores conocidos y otros novedosos asociados al inicio de la LM y los motivos de la madre para la toma de su decisión. Los tratamientos farmacológicos maternos son un factor asociado para no iniciar la LM, corregible con un asesoramiento adecuado. Urge adoptar medidas correctoras para conseguir tasas de inicio de la LM cercanas al 100%. Es necesaria la unificación de criterios respecto a lo que se considera «inicio de la LM» para comparar resultados de futuras investigaciones (AU)

Introduction: Breastfeeding benefits have been clearly demonstrated, but nearly 20% of mothers don’t start breastfeeding. Related factors to this decision and maternal reasons have been poorly investigated. We asses initiation breastfeeding rate, maternal reasons and the factors linked to their decision. Method: This is a prevalence study of initiation breastfeeding rate in a sample of mothers who delivered after 36 weeks of gestation. Six trained investigators collected variables by structured questionnaires, asking the mothers in the hospital within the first 24 hours after delivery. Bivariate and multivariate analysis of the data were performed. Results: Eighty one percent of the mothers started breastfeeding. Positive associated factors were: a good opinion of mother’s partner about breastfeeding (OR= 28.49; CI 95%: 5.34-151.95), neutral opinion of grandmother about breastfeeding (OR= 4.79; CI 95%: 0.99-23.76), positive breastfeeding experience with previous sibling (OR= 22.63; CI 95%: 5.68-90.07) and coming from the same province where the hospital is located (OR= 47.34; CI 95%: 16.09- 139.31). Negative related factors were: maternal smoking habit (OR= 0.37; CI 95%: 0.15-0.92), previous abortions (OR= 0.35; CI 95%: 0.20-0.60) and maternal pharmacological treatment at the beginning of breastfeeding (OR= 0.25; CI 95%: 0.08-0.74). Conclusions: We have described not only known but other new factors associated with the breastfeeding initiation, and maternal reasons for making their decisions. Pharmacological treatment is one of the factors clearly implicated in the beginning of formula-feeding, and this decision is avoidable with a correct counselling. Increasing breastfeeding initiation rates is strongly recommended with new public health interventions. Common criteria of what consider as a “breastfeeding initiation” are required for future research (AU)

Helicobacter pylori second-line rescue therapy with levofloxacin- and bismuth-containing quadruple therapy, after failure of standard triple or non-bismuth quadruple treatments.

BACKGROUND: The most commonly used second-line Helicobacter pylori eradication regimens are bismuth-containing quadruple therapy and levofloxacin-containing triple therapy, both offering suboptimal results. Combining bismuth and levofloxacin may enhance the efficacy of rescue eradication regimens. AIMS: To evaluate the efficacy and tolerability of a second-line quadruple regimen containing levofloxacin and bismuth in patients whose previous H. pylori eradication treatment failed. METHODS: This was a prospective multicenter study including patients in whom a standard triple therapy (PPI-clarithromycin-amoxicillin) or a non-bismuth quadruple therapy (PPI-clarithromycin-amoxicillin-metronidazole, either sequential or concomitant) had failed. Esomeprazole (40 mg b.d.), amoxicillin (1 g b.d.), levofloxacin (500 mg o.d.) and bismuth (240 mg b.d.) was prescribed for 14 days. Eradication was confirmed by (13) C-urea breath test. Compliance was determined through questioning and recovery of empty medication envelopes. Incidence of adverse effects was evaluated by questionnaires. RESULTS: 200 patients were included consecutively (mean age 47 years, 67% women, 13% ulcer). Previous failed therapy included: standard clarithromycin triple therapy (131 patients), sequential (32) and concomitant (37). A total of 96% took all medications correctly. Per-protocol and intention-to-treat eradication rates were 91.1% (95%CI = 87-95%) and 90% (95%CI = 86-94%). Cure rates were similar regardless of previous (failed) treatment or country of origin. Adverse effects were reported in 46% of patients, most commonly nausea (17%) and diarrhoea (16%); 3% were intense but none was serious. CONCLUSIONS: Fourteen-day bismuth- and levofloxacin-containing quadruple therapy is an effective (≥90% cure rate), simple and safe second-line strategy in patients whose previous standard triple or non-bismuth quadruple (sequential or concomitant) therapies have failed.

Facilitated ion transfer of protonated primary organic amines studied by square wave voltammetry and chronoamperometry.

The transfer of the protonated forms of heptylamine, octylamine, decylamine, procaine and procainamide facilitated by dibenzo-18-crown-6 from water to a solvent polymeric membrane has been investigated by using cyclic square wave voltammetry. The experimental voltammograms obtained are in good agreement with theoretical predictions. The values of the standard ion transfer potential, complexation constant and diffusion coefficient in water have been obtained from these experiments, and have been used to draw some conclusions about the lipophilicity of these species and the relative stability of the organic ammonium complexes with dibenzo-18-crown-6. The results have been compared with those provided by linear sweep voltammetry. Calibration graphs were obtained with both techniques. An interesting chronoamperometric method for the determination of the diffusion coefficient of the target ion in the membrane has been developed and applied to all these protonated amines.

Factores asociados al abandono precoz de la lactancia materna en una región del este de España / Factors associated with early weaning in a Spanish region

INTRODUCCIÓN: La lactancia materna (LM) tiene indudables beneficios para el recién nacido. En estudios previos se constata un abandono precoz de la misma, existiendo escasa evidencia sobre los factores asociados. Nuestro objetivo ha sido conocer la prevalencia de LM durante los primeros 12 meses posparto y analizar los factores asociados a su abandono. MATERIAL Y MÉTODOS: Estudio prospectivo, con inclusión consecutiva de pares (madre y recién nacido) hasta muestra requerida. Recogida de variables mediante encuestas maternas según el programa de seguimiento. Análisis estadístico bivariado y multivariado. RESULTADOS: Se seleccionaron 452 pares en los que se constató el inicio de la LM en el 81% de los casos, persistiendo a los 3 y 6 meses el 39 y 21% total, respectivamente. Los factores asociados al abandono precoz fueron: gestación tras técnicas de reproducción asistida (OR = 5,58; IC 95%: 2,62-11,91), hábito tabáquico materno (OR = 1,56; IC 95%: 1,10-2,22), expectativas pobres sobre la duración de la lactancia (OR = 2,19; IC 95%: 1,49-3,23), utilización de pezoneras (OR = 2,57; IC 95%: 1,69-3,90), uso rutinario del chupete durante el primer mes posparto (OR = 1,39; IC 95%: 1,02-1,91), madre con estudios universitarios (OR = 0,59; IC 95%: 0,40-0,88), asistencia a clases prenatales (OR = 0,68; IC 95%: 0,49-0,94), y sensación materna de leche suficiente al alta (OR = 0,66; IC 95%: 0,47-0,92). CONCLUSIONES: Las tasas de abandono de la LM en nuestro medio son elevadas, sin alcanzarse los objetivos de las recomendaciones internacionales al respecto. Se describen factores implicados ya conocidos y otros novedosos. Se recomiendan estrategias de intervención encaminadas a prolongar la LM

INTRODUCTION: Breastfeeding has undoubtedly great benefits. Previous studies have found anearly dropout. Only a few studies have investigated related factors. Our aim was to find outon-going breastfeeding rates along the first 12 months after birth and analyse factors associated with early weaning. MATERIAL AND METHODS: This is a prospective study including consecutive pairs (mother and newborn) till completion of the required sample. Variables were collected performing a structured program of surveys to the mothers. Bivariate and multivariate analysis of the data was performed. RESULTS: A total of 452 pairs were recruited. It was found that 81% of them started breastfeeding, with a prevalence of breastfeeding of 39% and 21% at 3 and 6 months after birth, respectively. Factors associated with early discontinuation of breastfeeding were: pregnancy induced by assisted reproduction methods (OR = 5.58; 95% CI: 2.62-11.91), maternal smoking(OR = 1.56; 95% CI: 1.10-2.22), poor maternal expectations about the duration of breastfeeding(OR = 2.19; 95% CI: 1.49-3.23), use of nipple shields for breastfeeding (OR = 2.57; 95% CI:1.69-3.90), pacifier use on a regular basis during the first month after delivery (OR = 1.39; 95%CI: 1.02-1.91), maternal university educational level (OR = 0,59; 95% CI: 0,40-0,88), attending birth preparation programs during pregnancy (OR = 0,68; 95% CI: 0,49-0,94), and believing having enough milk output at the time of discharge (OR = 0,66; 95% CI: 0,47-0,92). CONCLUSIONS: International recommendations about duration of breastfeeding are not achieved in our country because of high rates of early weaning. We describe the known factors involved and other novel factors. The implementation of interventions to increase breastfeeding rates and to prevent early weaning are strongly recommended

[Factors associated with early weaning in a Spanish region]. / Factores asociados al abandono precoz de la lactancia materna en una región del este de España.

INTRODUCTION: Breastfeeding has undoubtedly great benefits. Previous studies have foundan early dropout. Only a few studies have investigated related factors. Our aim was to find out on-going breastfeeding rates along the first 12 months after birth and analyse factors associated with early weaning. MATERIAL AND METHODS: This is a prospective study including consecutive pairs (mother and newborn) till completion of the required sample. Variables were collected performing a structured program of surveys to the mothers. Bivariate and multivariate analysis of the data was performed. RESULTS: A total of 452 pairs were recruited. It was found that 81% of them started breastfeeding, with a prevalence of breastfeeding of 39% and 21% at 3 and 6 months after birth, respectively. Factors associated with early discontinuation of breastfeeding were: pregnancy induced by assisted reproduction methods (OR=5.58; 95% CI: 2.62-11.91), maternal smoking (OR=1.56; 95% CI: 1.10-2.22), poor maternal expectations about the duration of breastfeeding (OR=2.19; 95% CI: 1.49-3.23), use of nipple shields for breastfeeding (OR=2.57; 95% CI: 1.69-3.90), pacifier use on a regular basis during the first month after delivery (OR=1.39; 95% CI: 1.02-1.91), maternal university educational level (OR=0,59; 95% CI: 0,40-0,88), attending birth preparation programs during pregnancy (OR=0,68; 95% CI: 0,49-0,94), and believing having enough milk output at the time of discharge (OR=0,66; 95% CI: 0,47-0,92). CONCLUSIONS: International recommendations about duration of breastfeeding are not achieved in our country because of high rates of early weaning. We describe the known factors involved and other novel factors. The implementation of interventions to increase breastfeeding rates and to prevent early weaning are strongly recommended.

First full-beam PET acquisitions in proton therapy with a modular dual-head dedicated system.

During particle therapy irradiation, positron emitters with half-lives ranging from 2 to 20 min are generated from nuclear processes. The half-lives are such that it is possible either to detect the positron signal in the treatment room using an in-beam positron emission tomography (PET) system, right after the irradiation, or to quickly transfer the patient to a close PET/CT scanner. Since the activity distribution is spatially correlated with the dose, it is possible to use PET imaging as an indirect method to assure the quality of the dose delivery. In this work, we present a new dedicated PET system able to operate in-beam. The PET apparatus consists in two 10 cm × 10 cm detector heads. Each detector is composed of four scintillating matrices of 23 × 23 LYSO crystals. The crystal size is 1.9 mm × 1.9 mm × 16 mm. Each scintillation matrix is read out independently with a modularized acquisition system. The distance between the two opposing detector heads was set to 20 cm. The system has very low dead time per detector area and a 3 ns coincidence window, which is capable to sustain high single count rates and to keep the random counts relatively low. This allows a new full-beam monitoring modality that includes data acquisition also while the beam is on. The PET system was tested during the irradiation at the CATANA (INFN, Catania, Italy) cyclotron-based proton therapy facility. Four acquisitions with different doses and dose rates were analysed. In all cases the random to total coincidences ratio was equal or less than 25%. For each measurement we estimated the accuracy and precision of the activity range on a set of voxel lines within an irradiated PMMA phantom. Results show that the inclusion of data acquired during the irradiation, referred to as beam-on data, improves both the precision and accuracy of the range measurement with respect to data acquired only after irradiation. Beam-on data alone are enough to give precisions better than 1 mm when at least 5 Gy are delivered.

Sequential combined therapy with omalizumab and rituximab: a new approach to severe atopic dermatitis.

BACKGROUND: Atopic dermatitis (AD) is a common chronic skin disease, and a significant percentage of AD patients have severe forms. Inflammation based on type 2 helper T cells (T(H)2), autoantibodies, and CD8+ T cells could play a relevant role in this disease. When the patient requires systemic immunosuppressors for disease control, side effects are frequent. We propose a sequential therapeutic strategy with 2 monoclonal antibodies, omalizumab (anti-immunoglobulin [Ig] E) and rituximab (anti-CD20), which might induce clinical benefit with few side effects in selected individuals with AD. METHODS: We report 6 cases of severe AD refractory to conventional therapy. The patients underwent sequential switch therapy with omalizumab and rituximab. Clinical response was assessed by means of the decrease in body surface affected. Immunological parameters and side effects were also monitored. RESULTS: Four patients received omalizumab before a high-dose cycle of rituximab. In the case of recurrences, either low-dose cycles of rituximab or omalizumab were administered. A long-term clinical benefit was observed in 3 out of 4 patients. Two patients first received high-dose rituximab followed by either low-dose rituximab or omalizumab, and one of them achieved a response at 17 months. No severe side effects were recorded. Serum IgE level and B-cell counts decreased with therapy, the latter returning to baseline levels 10 to 11 months after treatment. Specific antibody responses remained protective during the study. CONCLUSIONS: With our proposed switch therapy, 4 out of 6 patients achieved a dramatic clinical improvement. This novel strategy targets different arms of the immune response and might be a good alternative for patients with severe AD.

Massively parallelizable list-mode reconstruction using a Monte Carlo-based elliptical Gaussian model.

PURPOSE: A fully three-dimensional (3D) massively parallelizable list-mode ordered-subsets expectation-maximization (LM-OSEM) reconstruction algorithm has been developed for high-resolution PET cameras. System response probabilities are calculated online from a set of parameters derived from Monte Carlo simulations. The shape of a system response for a given line of response (LOR) has been shown to be asymmetrical around the LOR. This work has been focused on the development of efficient region-search techniques to sample the system response probabilities, which are suitable for asymmetric kernel models, including elliptical Gaussian models that allow for high accuracy and high parallelization efficiency. The novel region-search scheme using variable kernel models is applied in the proposed PET reconstruction algorithm. METHODS: A novel region-search technique has been used to sample the probability density function in correspondence with a small dynamic subset of the field of view that constitutes the region of response (ROR). The ROR is identified around the LOR by searching for any voxel within a dynamically calculated contour. The contour condition is currently defined as a fixed threshold over the posterior probability, and arbitrary kernel models can be applied using a numerical approach. The processing of the LORs is distributed in batches among the available computing devices, then, individual LORs are processed within different processing units. In this way, both multicore and multiple many-core processing units can be efficiently exploited. Tests have been conducted with probability models that take into account the noncolinearity, positron range, and crystal penetration effects, that produced tubes of response with varying elliptical sections whose axes were a function of the crystal's thickness and angle of incidence of the given LOR. The algorithm treats the probability model as a 3D scalar field defined within a reference system aligned with the ideal LOR. RESULTS: This new technique provides superior image quality in terms of signal-to-noise ratio as compared with the histogram-mode method based on precomputed system matrices available for a commercial small animal scanner. Reconstruction times can be kept low with the use of multicore, many-core architectures, including multiple graphic processing units. CONCLUSIONS: A highly parallelizable LM reconstruction method has been proposed based on Monte Carlo simulations and new parallelization techniques aimed at improving the reconstruction speed and the image signal-to-noise of a given OSEM algorithm. The method has been validated using simulated and real phantoms. A special advantage of the new method is the possibility of defining dynamically the cut-off threshold over the calculated probabilities thus allowing for a direct control on the trade-off between speed and quality during the reconstruction.

Consersvative surgery, external radiotherapy, and HDR brachyterapy in a single fraction of 7 Gy in early breast cancer: long term toxicity and esthetic assessment

INTRODUCTION: The essential issue in conservative treatment is the quality in breast preservation. When risk factors for local relapse exist, a tumour bed boost is required, but the boost choice remains controversial. Prospectively, we studied long-term toxicity, cosmetic outcome and prognostic factors. MATERIALS AND METHODS: After conservative treatment, 115 patients received a single dose of 7 Gy HDR-brachytherapy (HDR-BT) boost between June 1996 and December 2005. Late toxicity was assessed using the LENT-SOMA scale. For esthetic assessment, a subjective scale was used for patients and a modified Fehlauer scale for physicians. Mean age was 56.6 years. Invasive ductal carcinoma (78 %) and lumpectomy (60 %) were predominantly reported. 48 % received chemotherapy (CT). RESULTS: Regarding toxicity, 39 % of patients reported breast pain, 75 % fibrosis, 56 % telangiectasias, 19 % lymphoedema, and 51 % retraction/atrophy. Concerning management, 22 % of patients with pain and 45 % with lymphoedema were treated. The esthetic result was found satisfactory by 96 % of the patients and 85 % of the physicians. Fibrosis was influenced by CT and a larger irradiated volume and telangiectasias by a greater implant volume. CONCLUSIONS: HDR-BT boost shows good cosmetic effects with acceptable toxicity. Patients overestimate the esthetic outcome. LENT/SOMA is useful to assess chronic toxicity (AU)

Early-stage breast cancer conservative treatment: high-dose-rate brachytherapy boost in a single fraction of 700 cGy to the tumour bed

BACKGROUND AND PURPOSE: Conservative treatment represents the current therapy for early-stage breast cancer. When risk factors for local relapse exist, a tumour bed boost is required. Retrospectively, we evaluated the prognostic factors influencing local recurrence (LR), overall survival (OS) and disease-free survival (DFS). MATERIAL AND METHODS: After conservative treatment, 210 patients received a single-dose HDR brachytherapy (HDRBT) boost between June 1996 and December 2005. Mean age was 57 years; 75% had invasive ductal carcinoma. The most frequent surgery was lumpectomy (55.7%); 39.4% were G3, 18.6% intraductal component >25% and only 22% had negative margins. RESULTS: With a mean follow-up of 85 months, at 5 and 10 years the OS was 93% and 88%, DFS 92% and 89%, and LR 3.6% and 5.3%, respectively. For LR, the risk factors were carcinoma in situ, N+ and involved margins, whereas for metastasis, the risk factors were T2 tumours, stage III, N+ and the presence of local recurrence. CONCLUSIONS: HDR-BT boost in one fraction is an effective, simple and safe method for reducing LR. The outpatient setting and shorter treatment duration represent undeniable advantages (AU)

Assay of acetylcholinesterase activity by potentiometric monitoring of acetylcholine.

An acetylcholine-selective electrode based on a plasticized polymeric membrane has been developed. The electrode exhibited good selectivity for acetylcholine (ACh) over choline and some common ions, low drift, and a fast response to ACh. The response was linear over an ACh concentration range of 1×10(-6) to 1×10(-3) M with a slope of 59.1±0.1 and a detection limit of 1.5×10(-7)±1.2×10(-8) M. The electrode was used to monitor enzymatic ACh hydrolysis catalyzed by acetylcholinesterase (AChE) at different substrate and enzyme concentrations. A kinetic data analysis permitted the determination of the Michaelis-Menten constant of the enzymatic hydrolysis and AChE activity in the range of 2×10(-5) to 3.8×10(-1)U ml(-1).

Benzodipyrrole derivates as new ionophores for anion-selective electrodes: improving potentiometric selectivity towards divalent anions.

Two open substituted benzodipyrroles were tested as hydrogen-bond-forming anion ionophores for the development of anion-selective electrodes. These compounds were incorporated in plasticized polymeric membranes with different plasticizers, using different membrane compositions to explore their response towards several anions. The electrodes constructed with membranes containing 2-nitrophenyl octyl ether and a 0.5 molar ratio ionic additive/ionophore showed pronounced anti-Hofmeister behaviour, providing a significantly enhanced response towards the divalent anions sulfate, sulfite, thiosulfate and oxalate. The selected electrodes were also evaluated in terms of detection limits and selectivity. (1)H NMR experiments were carried out in an attempt to explain some aspects of the behaviour observed.