Challenging the Dogma: Stage migration or negative lymph nodes, which of them is the main player on gastric cancer prognosis?

Expanding loco-regional nodes harvesting is expected to increase survival. This improvement may be associated to stage migration (SM). However, the great bulk of harvested lymph nodes observed in large dissections is negative. M&M: 830 patients who received R0 gastrectomy for adenocarcinoma were included. pN+ patients with <26 nodes (n = 209) were included for a simulation to "offer 26 nodes" - SM (proportional and exponential based) was simulated and analysed through machine learning algorithms. Overall Survival (OS), in native and simulated stages, were compared. OS of extended lymphadenectomies (pN+, D ≥ 26, n = 273) was compared with the simulated curves. OS of patients in the following dissection intervals of negative nodes were compared: <16 (n = 233), 16-25 (n = 258), ≥26 (n = 339). RESULTS: After simulation to 26 nodes (pN+, D < 26 patients, n = 209), staging was recomputed. OS of native vs simulated early-stages (I-II) and advanced stages (III) were not different (p > 0.05). OS of patients with lymphadenectomy (≥26) was better than simulated for early and advanced stages (p = 0.008; p = 0.005). OS of patients included in distinct intervals of negative lymph nodes were different (p < 0.001). These intervals were an independent prognostic factor (multivariate analysis). CONCLUSIONS: The influence of Stage Migration was null in this set of simulations and Will Rogers phenomenon was not observed. Extended dissection performed better in OS. But the influence of the number of negative nodes, even in large dissections, was highlighted. By emphasizing the role of negative nodes, we aim to facilitate more informed decision-making in management of gastric cancer patients, ultimately leading to improved treatment outcomes and patient care.

Real-time monitoring of CdTe quantum dots growth in aqueous solution.

Quantum dots (QDs) are remarkable semiconductor nanoparticles, whose optical properties are strongly size-dependent. Therefore, the real-time monitoring of crystal growth pathway during synthesis gives an excellent opportunity to a smart design of the QDs luminescence. In this work, we present a new approach for monitoring the formation of QDs in aqueous solution up to 90 °C, through in situ luminescence analysis, using CdTe as a model system. This technique allows a detailed examination of the evolution of their light emission. In contrast to in situ absorbance analysis, the in situ luminescence measurements in reflection geometry are particularly advantageous once they are not hindered by the concentration increase of the colloidal suspension. The synthesized particles were additionally characterized using X-ray diffraction analysis, transition electron microscopy, UV-Vis absorption and infrared spectroscopy. The infrared spectra showed that 3-mercaptopropionic acid (MPA)-based thiols are covalently bound on the surface of QDs and microscopy revealed the formation of CdS. Setting a total of 3 h of reaction time, for instance, the QDs synthesized at 70, 80 and 90 °C exhibit emission maxima centered at 550, 600 and 655 nm. The in situ monitoring approach opens doors for a more precise achievement of the desired emission wavelength of QDs.

Hepatocellular Carcinoma in Ceará: Epidemiology and Treatment in a Reference Liver Transplant Center in Northeast Brazil.

Hepatocellular carcinoma remains a significant worldwide malignancy and an important cause of cancer-related death. The incidence is increasing globally. In Latin America, there is no consistent data on the epidemiology of hepatocellular carcinoma. However, Brazil is considered a country with an intermediate incidence of this liver neoplasm. In the state of Ceará, situated in the northeast region of Brazil, there are no consistent clinical and epidemiologic data on the actual incidence and the treatment of hepatocellular carcinoma. The purpose of this article is to describe epidemiologic characteristics and treatment forms of patients with hepatocellular carcinoma who were treated in a Liver Transplant Center. A retrospective observational study was conducted using the database from the register of 299 patients with hepatocellular carcinoma between June 2004 and February 2022. Only patients born in Ceará were included. Therefore, most patients were eligible, based on the Milan Criteria, to undergo liver transplantation with a Model End Stage Liver Disease score of 12.48 ± 4.66 points, and the waiting list time was approximately 7 months with 8.7% hepatocellular carcinoma recurrence after liver transplant. A total of 38.5 % of cases were outside the Milan criteria at the time of cancer diagnosis, and transarterial chemoembolization was the main treatment choice. In conclusion, the diagnosis of hepatocellular carcinoma in Ceará mainly occurs in male patients with hepatitis C or alcoholism, with a mean age of 61.55 years and a previous diagnosis of liver disease. Liver transplantation was the best curative therapeutic form in patients with cirrhosis and hepatocellular carcinoma in Ceará, where a significant number of patients were diagnosed with intermediate and advanced-stage hepatocellular carcinoma, so public health policies are important for the screening and monitoring of liver disease.

A scoping review of person-centred care strategies used in diagnostic Nuclear Medicine.

INTRODUCTION: Person-centred care (PCC) emphasises the need for the health care professional to prioritise individual patient needs, thereby fostering a collaborative and emphatic environment that empowers patients to actively participate in their own care. This article will explore the purpose of PCC in Nuclear Medicine (NM), while discussing strategies that may be used to implement PCC during diagnostic NM examinations performed on adult patients. METHODS: The scoping review was conducted in accordance with the Joanna Briggs Institute methodology. The search was performed on PubMed, Embase and Cinhal in June 2023 and included studies in English, Spanish, Portuguese and Italian. The research equation combined keywords and Medical Subject Heading terms (MeSH) related to person-centred care (PCC), for all types of nuclear medicine diagnostic examinations performed. Three independent review authors screened all abstracts and titles, and all eligible full-text publications were included in this scoping review. RESULTS: Fifty-three articles, published between 1993 and 2022, met the inclusion criteria for this scoping review. Seven articles were published in 2015 while 56.6 % of all included studies were performed in Europe. Most studies (n = 39/53) focused on the patients only, with the identified patient benefits being: improve patient experience (67.9 %), increase patient comfort (13.2 %), increase patient knowledge (5.7 %), reduction of patient anxiety (9.4 %) and reduction of waiting/scan time (3.8 %). CONCLUSION: The scoping review identified a lack of research investigating the use of person-centred care strategies in NM. Future research will focus on using an international survey to explore this topic in nuclear medicine departments overseas. IMPLICATIONS FOR PRACTICE: By applying PCC principles, the NM professional can improve the patient care pathway and increase patient satisfaction, leading to enhanced clinical outcomes.

Unresectable stage III non-small cell lung cancer: Insights from a Portuguese expert panel.

INTRODUCTION: The management of unresectable stage III non-small cell lung cancer (NSCLC) is clinically challenging and there is no current consensus on optimal strategies. Herein, a panel of Portuguese experts aims to present practical recommendations for the global management of unresectable stage III NSCLC patients. METHODS: A group of Portuguese lung cancer experts debated aspects related to the diagnosis, staging and treatment of unresectable stage III NSCLC in light of current evidence. Recent breakthroughs in immunotherapy as part of a standard therapeutic approach were also discussed. This review exposes the major conclusions obtained. RESULTS: Practical recommendations for the management of unresectable stage III NSCLC were proposed, aiming to improve the pathways of diagnosis and treatment in the Portuguese healthcare system. Clinical heterogeneity of patients with stage III NSCLC hinders the development of single standardised algorithm where all fit. CONCLUSIONS: A timely diagnosis and a proper staging contribute to the best management of each patient, optimizing treatment tolerance and effectiveness. The expert panel considered chemoradiotherapy as the preferable approach when surgery is not possible. Management of adverse events and immunotherapy as a consolidation therapy are also essential steps for a successful strategy.

Cardiovascular and metabolic comorbidities in patients with thyroid nodules: the impact of incidental diagnosis.

PURPOSE: The prevalence of thyroid nodules (TN) in the general population has increased as screening procedures are implemented and an association with metabolic and cardiovascular disorders has been reported. The aim of this study was to investigate the reason leading to the diagnosis of TN and to compare the clinical characteristics of patients diagnosed incidentally with those of patients diagnosed for thyroid-related reasons. METHODS: We designed a retrospective cross-sectional study including consecutive patients with TN from two high-volume hospital-based centers for thyroid diseases (Pavia and Messina) in Italy. Data regarding reason leading to TN diagnosis, age, sex, BMI, presence of cardio-metabolic comorbidities were collected. RESULTS: Among the 623 enrolled subjects, the US diagnosis of TN was prompted by thyroid-related reasons in 421 (67.6%, TD group) and incidental in 202 (32.4%, ID group) with a similar distribution in the two centers (p = 0.960). The ID group patients were more frequently males (38.6% vs 22.1%, p < 0.001) and significantly older (58.9 ± 13.7 vs 50.6 ± 15.5 years, p < 0.001) than the TD group ones, and had a higher rate of cardiovascular comorbidities (73.8% vs 47.5%, p < 0.001), despite having a similar BMI (27.9 ± 5.2 vs 27.8 ± 13.5, p = 0.893). CONCLUSIONS: Stratification of patients with TN according to the diagnostic procedure leading to diagnosis allows a better epidemiological characterization of this inhomogeneous and large population.

Does rassi score caracterize patients with chagas disease with complex ventricular arrhythmias?

INTRODUCTION: Rassi score (NYHA functional class III/IV HF [5 points], cardiomegaly [5 points], contractions abnormalities [3 points], non-sustained ventricular tachycardia [3 points], low amplitude QRS [2 points] and male sex [2 points]) is used in the clinic for risk stratification due to cardiovascular death in patients with Chagas disease (P-CD). Whether this score has any role in identifying patients at risk of complex ventricular arrhythmias has not been determined. OBJECTIVE: Assess whether there is an association between Rassi score and the presence of potentially malignant complex ventricular arrhythmias in P-CD. METHODS: 79 P-CD (34 men, age 61±11 years-old), consecutively referred for 24h-Holter were divided into 2 groups: low risk Rassi score (57 P, 0-6 points) and medium-high risk (22 P, 7-20 points). The amount and complexity of ventricular arrhythmia (> 30/ h, ventricular tachycardia [VT]), LVEF, heart rate turbulence (HRT) indexes (turbulence onset [TO] and turbulence slope [TS]) and HRT category (0 [without disautonomy], 1 and/or 2 [presence of disautonomy]) were evaluated. RESULTS: Compared to P-CD with low risk score, those with medium-high risk had more ventricular arrhythmias, lower LVEF, worse HRT indexes and more HRT categories 1 and/or 2 (see table below). CONCLUSIONS: 1) P-CD and Rassi score of medium to high risk have a greater amount of ventricular arrhythmias; 2) These findings can be explained by the presence of greater degree of disautonomy, assessed by HRT, and by the lower LVEF; 3) Prospective studies are necessary to confirm these findings in clinical practice.

Joint EANM/SNMMI guideline on radiomics in nuclear medicine : Jointly supported by the EANM Physics Committee and the SNMMI Physics, Instrumentation and Data Sciences Council.

PURPOSE: The purpose of this guideline is to provide comprehensive information on best practices for robust radiomics analyses for both hand-crafted and deep learning-based approaches. METHODS: In a cooperative effort between the EANM and SNMMI, we agreed upon current best practices and recommendations for relevant aspects of radiomics analyses, including study design, quality assurance, data collection, impact of acquisition and reconstruction, detection and segmentation, feature standardization and implementation, as well as appropriate modelling schemes, model evaluation, and interpretation. We also offer an outlook for future perspectives. CONCLUSION: Radiomics is a very quickly evolving field of research. The present guideline focused on established findings as well as recommendations based on the state of the art. Though this guideline recognizes both hand-crafted and deep learning-based radiomics approaches, it primarily focuses on the former as this field is more mature. This guideline will be updated once more studies and results have contributed to improved consensus regarding the application of deep learning methods for radiomics. Although methodological recommendations in the present document are valid for most medical image modalities, we focus here on nuclear medicine, and specific recommendations when necessary are made for PET/CT, PET/MR, and quantitative SPECT.

Modification of [18F]-FDG PET/CT imaging protocols in obese oncology patients: A nationwide survey.

INTRODUCTION: The use of medical imaging for diagnosis, staging and follow-up in Oncology context is incredibly important, being the use of [18F]-FDG PET/CT particularly advantageous in specific contexts like the case of obese patients. However, imaging the latter can be challenging sometimes, since their own body size may affect overall image quality and adds technical difficulties for the operator(s) performing the examination. METHODS: This research project was developed with the aim of analysing the current personal practices of Portuguese Nuclear Medicine Technologists (NMTs) in the adaptation of 18F-FDG PET/CT oncological protocols for obese patients and comparing the results with parameters referenced in literature. A non-experimental research study was conducted using a survey delivered online to NMTs through social media platforms (Facebook® and LinkedIn®) and by sending the link directly to contacts within the research team professional and personal networks. RESULTS: Answers from a total of 26 participants were obtained, with 88.5% of participants admitting modifying technical protocols in examinations for obese patients. Changes in PET protocols included an increase in the administered activity (60.9%), an increase in scan time per individual bed position (69.6%) and the use of Time-of-Flight (TOF) technology whenever available. Protocol changes in CT included increasing the mA (82.6%), raising the KVp (47.8%), the application of iterative reconstruction (69.6%) and the use of automatic exposure control (AEC) (52.2%). The remaining parameters (pitch, algorithm, slice thickness, display FOV, gantry rotation time and energy acceptance window) were claimed not to be modified by around 90% of professionals. CONCLUSION: Portuguese NMTs tend to change the [18F]-FDG PET/CT protocols for obese patients. However, while some of the parameters appear to be contradictory or redundant, others require further optimisation, especially in the CT component. IMPLICATIONS FOR PRACTICE: Efforts should be made to optimize acquisition protocols used in [18F]-FDG PET/CT scans for obese patients.

The effects of TiO2 nanotubes on bond strength and radiopacity of a self-adhesive resin cement in self-curing mode / Os efeitos de nanotubos de TiO2 na resistência de união e radiopacidade de um cimento resinoso auto-adesivo no modo auto-polimerizável

Objective: The aim of this in vitro study w as t o analyze the influence of the titanium dioxide nanotubes i n a self-cure mode polymerization of a dual resin luting agent through push out bond strength and radiopacity tests. Material and Methods: After mixed with a commercial du al self-adhesive resin cement, three concentrations o f tit anium dioxide nanotubes (0.3, 0.6, and 0.9% by weight) we re analyzed in self-curing mode. T he bond strength to bovine root dentin and fi berglass posts was assessed with the push out bond str ength t est and was evaluated in three thirds (cervical, middle and apical) (n=10), followed by failure mode analysis (SEM), and the ISO standard 9917-2 was followed for radiopacity test (n=10). Data were statistically analyzed by one-way ANOVA test, followed by Tukey's test (α=0.05). Results: Reinforced self-adhesive resin cement with 0.6% titanium dioxide nanotubes showed significant difference compared to the control gr oup for push out test (p=0.00158). The modified groups did not s how significant difference among thirds (p=0.782). Radiopacity sh owed higher value for group w ith 0.9% titanium dioxide nanotubes in comparison w ith control group (p<0.001). Conclusion: The addition of titanium dioxide nanotubes to a self-adhesive resin cement increased the bond strength to dentin and radiopacity values in the self-cure polymerization mode (AU)

Objetivo: O objetivo deste estudo in vitro foi analisar a influência de nanotubos de dióxido de titânio na polimerização química de um agente cimentante resinoso dual através de testes de resistência à união e radiopacidade. Material e Métodos: Após misturado com um cimento resinoso auto-adesivo comercial, três concentrações de nanotubos de dióxido de titânio (0,3, 0,6 e 0,9% em peso) foram analisadas. A resistência da união para a dentina da raiz bovina e os pinos de fibra de vidro foi avaliada pelo teste de push-out e avaliada em três terços (cervical, médio e apical) (n = 10), seguido pelo análise de modo de falha (MEV) e a norma ISO 9917-2 foi seguido para teste de radiopacidade (n = 10). Os dados foram analisados estatisticamente pelo teste ANOVA um fator seguido do teste de Tukey (α = 0,05). Resultados: O cimento resinoso auto-adesivo reforçado com nanotubos de dióxido de titânio a 0,6% mostrou diferença significativa em comparação com o grupo controle para teste de push-out (p=0,00158). Os grupos modificados não mostraram diferença significativa entre os terços (p=0,782). A radiopacidade mostrou maior valor para o grupo com nanotubos de dióxido de titânio 0,9% em comparação com o grupo controle (p<0,001). Conclusão: A adição de nanotubos de dióxido de titânio a um cimento resinoso auto-adesivo aumentou a os valores de resistência de união à dentina e radiopacidade no modo de polimerização química do agente cimentante (AU)

The effect of filling technique on the cuspal strain, polymerization shrinkage stress, enamel crack formation and depth of cure of restored molars.

OBJECTIVE: Evaluate the effect of different restorative filling techniques on the residual shrinkage stress (ShrS), cuspal strain (CS), depth of cure (DC), and enamel crack formation (Ec) in molars with MOD restorations. METHODS: Post-gel shrinkage, elastic modulus, compressive and diametral tensile strength of the Filtek One Bulk Fill composite were calculated. Sixty molars with MOD preparations were restored using four filling techniques: Bulk; Horizontal; Oblique; Natural enamel and dentin substitution (NEDS) technique. CS was measured using a strain gauge (n = 10). The DC (n = 5) was measured using Knoop hardness. Shrinkage stress/strain was analyzed using 3D finite element analysis. The Ec analysis was carried out by transillumination. Two-way ANOVA with repeated measures and Tukey's HSD test (α = 0.05) was performed for the CS data. Two-Way ANOVA and Tukey's HSD test was performed for the DC data (α = 0.05). RESULTS: CS was higher at the lingual cusp for the horizontal and NEDS technique. No statistical difference was found between the buccal and lingual CS values for the Bulk (p = 0.367) or Oblique techniques (p = 0.192). CS values were lower for the Bulk. More enamel cracks were found for the Bulk. DC was lower at 4 mm regardless the filling technique. The Horizontal showed the highest ShrS values. The Bulk generated the lower ShrS values. SIGNIFICANCE: A Bulk technique caused the lowest shrinkage stress/strain. An Oblique technique yielded the best balance between stress, strain and crack formation. NEDS technique is a good alternative to decrease the number of increments while maintaining the stress levels nearby the Oblique technique.

Dopamine depletion in wistar rats with epilepsy.

The dopamine content in cerebral structures has been related to neuronal excitability and several approaches have been used to study this phenomenon during seizure vulnerability period. In the present work, we describe the effects of dopamine depletion after the administration of 6-hidroxidopamine (6-OHDA) into the substantia nigra pars compacta of male rats submitted to the pilocarpine model of epilepsy. Susceptibility to pilocarpine-induced status epilepticus (SE), as well as spontaneous and recurrent seizures (SRSs) frequency during the chronic period of the model were determined. Since the hippocampus is one of main structures in the development of this experimental model of epilepsy, the dopamine levels in this region were also determined after drug administration. In the first experiment, 62% (15/24) of 6-OHDA pre-treated rats and 45% (11/24) of those receiving ascorbic acid as control solution progressed to motor limbic seizures evolving to SE, after the administration of pilocarpine. Severeness of seizures during the model´s the acute period, was significantly higher in epileptic experimental rats (56.52%), than in controls (4.16%). In the second experiment, the frequency of seizures in the model's chronic phase did not significantly change between groups. Our data show that dopamine may play an important role on seizure severity in the pilo's model acute period, which seems to be due to dopamine inhibitory action on motor expression of seizure.

Seed priming with light quality and Cyperus rotundus L. extract modulate the germination and initial growth of Moringa oleifera Lam. seedlings.

Improving plant germination is essential to guarantee better quality seedlings. Thus, this research aimed to evaluate whether the seed priming with light quality (LIQ) and the aqueous extract of Cyperus rotundus (AEC) tuber could modulate the germination and initial growth of Moringa oleifera L. seedlings. The experimental design was a completely randomized in the 4x4 factorial scheme, composed of four LIQ conditions (white, blue, red, and distant red light) and four AEC concentrations (0, 25, 50 and 100%). Seed priming with red light reduced the average emergence time, while blue, red, and extreme red lights associated with 50% of aqueous extract of C. rotundus increased shoot initial length and photosynthetic pigment accumulation. Seed priming with blue light resulted in seedlings with a shorter final shoot length. However, application of 100% of aqueous extract of C. rotundus reversed this. The white light in combination with concentrations of 50 and 100% of AEC promoted a higher relative shoot growth rate of seedlings. The research revealed that seed priming with light quality and aqueous extracts of C. rotundus tubers modulates the germination and initial growth of M. oleifera seedlings. More work needs to be done to determine the responsible compounds in AEC that is responsible for priming growth as phytohormones.

Antimicrobial resistance, biofilm production and invasion of mammary epithelial cells by Enterococcus faecalis and Enterococcus mundtii strains isolated from bovine subclinical mastitis in Brazil.

Members of the genus Enterococcus are among the most relevant etiologic agents of bovine clinical and subclinical mastitis, a major problem for the dairy industry. In Brazil, clonal diversity, and multidrug resistance profiles related to bovine infections need further investigation. In this study, 11 bacterial strains recovered from mastitis subclinical cases detected in different farms of São Paulo, Brazil, were identified as Enterococcus faecalis (n = 8) and Enterococcus mundtii (n = 3) by biochemical testing and MALDI-TOF mass spectrometry. Pulsed-field gel electrophoresis categorized the enterococcal isolates into two main clusters (A and B) with similarity ranging from 85 to 100%. The isolates were shown to be resistant tetracycline (73%), erythromycin (73%), quinupristin-dalphopristin (64%), norfloxacin (9%), fosfomycin (9%) and linezolid (9%). Moreover, seven strains (64%) were considered multidrug-resistant. All the isolates were able to produce biofilms when grown in milk for 24 h: 54·54% were classified as moderate producers and 45·45% were weak producers. Interestingly, only two strains (Ef17 and Em42) remained as moderate biofilm producers after 48 h incubation. Moreover, all isolates showed no ability to form biofilm in tryptic soy broth (TSB) after 24 and 48 h incubation. In addition, cytoskeleton components were partially involved in E. faecalis and E. mundtii entry to epithelial cells as demonstrated by induction of actin stress fibre. In conclusion, enterococci isolates recovered from bovine subclinical mastitis were resistant to several classes of antibiotics, showing the ability to form biofilms in milk and invade mammary epithelial cells, suggesting an advantageous feature in mammary gland colonization during mastitis development. In addition, they can spread along the food chain by different routes and eventually constitute a possible threat for public health, including E. mundtii specie.

Small understorey trees have greater capacity than canopy trees to adjust hydraulic traits following prolonged experimental drought in a tropical forest.

Future climate change predictions for tropical forests highlight increased frequency and intensity of extreme drought events. However, it remains unclear whether large and small trees have differential strategies to tolerate drought due to the different niches they occupy. The future of tropical forests is ultimately dependent on the capacity of small trees (<10 cm in diameter) to adjust their hydraulic system to tolerate drought. To address this question, we evaluated whether the drought tolerance of neotropical small trees can adjust to experimental water stress and was different from tall trees. We measured multiple drought resistance-related hydraulic traits across nine common neotropical genera at the world's longest-running tropical forest throughfall-exclusion experiment and compared their responses with surviving large canopy trees. Small understorey trees in both the control and the throughfall-exclusion treatment had lower minimum stomatal conductance and maximum hydraulic leaf-specific conductivity relative to large trees of the same genera, as well as a greater hydraulic safety margin (HSM), percentage loss of conductivity and embolism resistance, demonstrating that they occupy a distinct hydraulic niche. Surprisingly, in response to the drought treatment, small trees increased specific hydraulic conductivity by 56.3% and leaf:sapwood area ratio by 45.6%. The greater HSM of small understorey trees relative to large canopy trees likely enabled them to adjust other aspects of their hydraulic systems to increase hydraulic conductivity and take advantage of increases in light availability in the understorey resulting from the drought-induced mortality of canopy trees. Our results demonstrate that differences in hydraulic strategies between small understorey and large canopy trees drive hydraulic niche segregation. Small understorey trees can adjust their hydraulic systems in response to changes in water and light availability, indicating that natural regeneration of tropical forests following long-term drought may be possible.

Can a ToF-PET photon attenuation reconstruction test stopping-power estimations in proton therapy? A phantom study.

Objective. The aim of the phantom study was to validate and to improve the computed tomography (CT) images used for the dose computation in proton therapy. It was tested, if the joint reconstruction of activity and attenuation images of time-of-flight PET (ToF-PET) scans could improve the estimation of the proton stopping-power.Approach. The attenuation images, i.e. CT images with 511 keV gamma-rays (γCTs), were jointly reconstructed with activity maps from ToF-PET scans. Theß+activity was produced with FDG and in a separate experiment with proton-induced radioactivation. The phantoms contained slabs of tissue substitutes. The use of theγCTs for the prediction of the beam stopping in proton therapy was based on a linear relationship between theγ-ray attenuation, the electron density, and the stopping-power of fast protons.Main results. The FDG based experiment showed sufficient linearity to detect a bias of bony tissue in the heuristic look-up table, which maps between x-ray CT images and proton stopping-power.γCTs can be used for dose computation, if the electron density of one type of tissue is provided as a scaling factor. A possible limitation is imposed by the spatial resolution, which is inferior by a factor of 2.5 compared to the one of the x-ray CT.γCTs can also be derived from off-line, ToF-PET scans subsequent to the application of a proton field with a hypofractionated dose level.Significance. γCTs are a viable tool to support the estimation of proton stopping with radiotracer-based ToF-PET data from diagnosis or staging. This could be of higher potential relevance in MRI-guided proton therapy.γCTs could form an alternative approach to make use of in-beam or off-line PET scans of proton-inducedß+activity with possible clinical limitations due to the low number of coincidence counts.

Associations of plasma lipids, lipoproteins, and cardiovascular outcomes with climatic variations in a large Brazilian population of Campinas, São Paulo state: an eight-year study.

In this eight-year retrospective study, we evaluated the associations between climatic variations and the biological rhythms in plasma lipids and lipoproteins in a large population of Campinas, São Paulo state, Brazil, as well as temporal changes of outcomes of cardiovascular hospitalizations. Climatic variables were obtained at the Center for Meteorological and Climatic Research Applied to Agriculture (University of Campinas - Unicamp, Brazil). The plasma lipid databases surveyed were from 27,543 individuals who had their lipid profiles assessed at the state university referral hospital in Campinas (Unicamp). The frequency of hospitalizations was obtained from the Brazilian Public Health database (DATASUS). Temporal statistical analyses were performed using the methods Cosinor or Friedman (ARIMA) and the temporal series were compared by cross-correlation functions. In normolipidemic cases (n=11,892), significantly different rhythmicity was observed in low-density lipoprotein (LDL)- and high-density lipoprotein (HDL)-cholesterol (C) both higher in winter and lower in summer. Dyslipidemia (n=15,651) increased the number and amplitude of lipid rhythms: LDL-C and HDL-C were higher in winter and lower in summer, and the opposite occurred with triglycerides. The number of hospitalizations showed maximum and minimum frequencies in winter and in summer, respectively. A coincident rhythmicity was observed of lower temperature and humidity rates with higher plasma LDL-C, and their temporal series were inversely cross-correlated. This study shows for the first time that variations of temperature, humidity, and daylight length were strongly associated with LDL-C and HDL-C seasonality, but moderately to lowly associated with rhythmicity of atherosclerotic outcomes. It also indicates unfavorable cardiovascular-related changes during wintertime.