What do we know About the Usefulness of 18F-FDG PET-CT for the Management of Invasive Fungal Infection? An International Survey.

BACKGROUND: Recent data support 18F-FDG PET-CT for the management of infections in immunocompromised patients, including invasive fungal infection (IFI). However, its role is not well established in clinical practice. We performed an international survey to evaluate the knowledge of physicians about the usefulness of 18F-FDG PET-CT in IFI, in order to define areas of uncertainty. METHODS: An online survey was distributed to infectious diseases working groups in December 2023-January 2024. It included questions regarding access to 18F-FDG PET-CT, knowledge on its usefulness for IFI and experience of the respondents. A descriptive analysis was performed. RESULTS: 180 respondents answered; 60.5% were Infectious Diseases specialists mainly from Spain (52.8%) and Italy (23.3%). 84.4% had access to 18F-FDG PET-CT at their own center. 85.6% considered that 18F-FDG PET-CT could be better than conventional tests for IFI. In the context of IFI risk, 81.1% would consider performing 18F-FDG PET-CT to study fever without a source and around 50% to evaluate silent lesions and 50% to assess response, including distinguishing residual from active lesions. Based on the results of the follow-up 18F-FDG PET-CT, 56.7% would adjust antifungal therapy duration. 60% would consider a change in the diagnostic or therapeutic strategy in case of increased uptake or new lesions. Uncovering occult lesions (52%) and diagnosing/excluding endocarditis (52.7%) were the situations in which 18F-FDG PET-CT was considered to have the most added value. There was a great variability in responses about timing, duration of uptake, the threshold for discontinuing treatment or the influence of immune status. CONCLUSION: Although the majority considered that 18F-FDG PET-CT may be useful for IFI, many areas of uncertainty remain. There is a need for protocolized research to improve IFI management.

Using deep-belief networks to understand propensity for livelihood change in a rural coastal community to further conservation.

Overharvesting of terrestrial and marine resources may be alleviated by encouraging an alternative configuration of livelihoods, particularly in rural communities in developing countries. Typical occupations in such areas include fishing and farming, and rural households often switch livelihood activities to suit climate and economic conditions. We used a machine-learning tool, deep-belief networks (DBN), and data from surveys of a rural Philippine coastal community to examine household desire to change livelihood. This desire is affected by a variety of factors, such as income, family needs, and feelings of work satisfaction, that are interrelated in complex ways. In farming households, livelihood changes often occur to diversify resources, increase income, and lessen economic risk. The DBN, given its multilayer perceptron structure, has a capacity to model nonlinear relationships among factors while providing an acceptable degree of accuracy. Relative to a set of 34 features (e.g., education, boat ownership, and work satisfaction), we examined the binary response variables desire to change work or not to change work. The best network had a test set accuracy of 97.5%. Among the features, 7 significantly affected desire to shift work: ethnicity, work satisfaction, number of persons in a household in ill health, number of fighting cocks owned, fishing engagement, buy-and-sell revenue, and educational level. A cross-correlation matrix of these 7 features indicated households less inclined to change work were those engaged in fishing and retail buying and selling. For fishing, provision of economic and other incentives should be considered to encourage changing from this occupation to allow recovery of fishery resources.

Uso de Redes de Creencia Profunda para Entender la Predisposición por el Cambio en el Medio de Vida en una Comunidad Rural Costera para Promover la Conservación Resumen La sobrexplotación de los recursos terrestres y marinos puede ser mitigada promoviendo una configuración alternativa de los medios de vida, particularmente en las comunidades rurales de los países en desarrollo. Las ocupaciones típicas en dichas áreas incluyen la pesca y la agricultura, y los hogares rurales comúnmente alternan entre estas actividades de sustento para ajustarse a las condiciones climáticas y económicas. Usamos una herramienta de aprendizaje automático, redes de creencia profunda (RCP) y datos tomados de censos aplicados a una comunidad rural costera en las Filipinas para examinar el deseo de cada hogar por cambiar su medio de vida. Este deseo se ve afectado por una variedad de factores, como el nivel de ingreso, las necesidades familiares y la sensación de satisfacción laboral, que están interrelacionados de maneras complejas. En los hogares agricultores, los cambios en el medio de vida ocurren con frecuencia para diversificar los recursos, aumentar el ingreso y disminuir el riesgo económico. Las RCP, dada la estructura multicapa de su perceptrón, tiene una capacidad para modelar las relaciones no lineales entre los factores mientras proporciona un grado aceptable de precisión. En relación con un conjunto de 34 caracteres (p. Ej.: educación, propiedad de navíos, satisfacción laboral), examinamos las variables de respuesta binaria deseo cambiar de trabajo y no deseo cambiar de trabajo. La mejor red tuvo una precisión de conjunto de pruebas del 97.5%. Entre los caracteres, siete afectaron significativamente el deseo por cambiar de trabajo: la etnicidad, la satisfacción laboral, el número de personas con mala salud en un mismo hogar, el número de gallos de pelea en su propiedad, la participación dentro de la pesca, los ingresos por compra y venta, y el nivel educativo. Una matriz de correlación cruzada de estos siete caracteres indicó que los hogares con una menor tendencia hacia el cambio de trabajo fueron aquellos que participan en la pesca y en la compra y venta al menudeo. Para la pesca, el suministro de incentivos económicos y de otros tipos debería considerarse para promover el cambio de esta ocupación y así permitir la recuperación de los recursos pesqueros.

Natural acidified marine systems: Lessons and predictions.

Natural acidified marine systems (ASs) are environments with relatively low pH levels due to natural causes such as volcanic activity, geochemical reactions, and biological processes. These systems act as natural laboratories for the study of the effects of ocean acidification, allowing for the observation of long-term ecological and evolutionary responses. Understanding these systems is crucial for predicting the effects of anthropogenic ocean acidification (OA) on marine ecosystems. There are 23 ASs in which scientific research has shown significant parallelisms in their results worldwide, such as the disappearance of calcareous organisms and the loss of species with key ecological functions under OA conditions. Future research should emphasize continuous collaboration among teams, as well as public access to oceanographic and biological data along with the monitoring of environmental variables at each AS. To preserve these areas, it is imperative to employ non-destructive methods and protect them as human heritage sites.

Decoding polymyalgia rheumatica, the role of Nuclear Medicine Imaging.

Polymyalgia rheumatica (PMR) is an inflammatory joint disease that presents in patients older than 50 years with prolonged morning pain and stiffness in the shoulder and hip joints and neck. The lack of specific clinical findings, laboratory signs, biomarkers and established imaging methods makes it difficult to diagnose patients with this disease. 18F-FDG PET/CT is a functional imaging technique that is an established tool in oncology and has also proven useful in the field of inflammatory diseases. The aim of this paper is to present literature evidence on the use of molecular imaging methods such as PET/CT for early diagnosis, assessment of disease activity and therapeutic response in PMR. At the same time, the advantages, disadvantages and contraindications of other methods are considered.

Identification of the PTPN22 functional variant R620W as susceptibility genetic factor for giant cell arteritis.

OBJECTIVE: To analyse the role of the PTPN22 and CSK genes, previously associated with autoimmunity, in the predisposition and clinical phenotypes of giant cell arteritis (GCA). METHODS: Our study population was composed of 911 patients diagnosed with biopsy-proven GCA and 8136 unaffected controls from a Spanish discovery cohort and three additional independent replication cohorts from Germany, Norway and the UK. Two functional PTPN22 polymorphisms (rs2476601/R620W and rs33996649/R263Q) and two variants of the CSK gene (rs1378942 and rs34933034) were genotyped using predesigned TaqMan assays. RESULTS: The analysis of the discovery cohort provided evidence of association of PTPN22 rs2476601/R620W with GCA (PFDR=1.06E-04, OR=1.62, CI 95% 1.29 to 2.04). The association did not appear to follow a specific GCA subphenotype. No statistically significant differences between allele frequencies for the other PTPN22 and CSK genetic variants were evident either in the case/control or in stratified case analysis. To confirm the detected PTPN22 association, three replication cohorts were genotyped, and a consistent association between the PTPN22 rs2476601/R620W variant and GCA was evident in the overall meta-analysis (PMH=2.00E-06, OR=1.51, CI 95% 1.28 to 1.79). CONCLUSIONS: Our results suggest that the PTPN22 polymorphism rs2476601/R620W plays an important role in the genetic risk to GCA.

Is there visceral adipose tissue (VAT) intracellular hypercortisolism in human obesity?

The fact that obesity is a prominent feature of Cushing's syndrome (systemic hypercortisolism of adrenocortical origin) stimulated a 40-year search for evidence of systemic hypercortisolism in human obesity. That search has failed to find such evidence. For the past 15 years, however, studies have been done to evaluate a possible alternative type of hypercortisolism in obesity, namely visceral adipose tissue (VAT) intracellular hypercortisolism. The current review summarizes the evidence published so far about this possibility. There have been three types of evidence studied: direct measurement of the VAT levels of 11ß-hydroxysteroid dehydrogenase type I (11-HSD-1), which converts biologically inactive cortisone to biologically active cortisol; direct measurement of splanchnic cortisol production; and evaluation of the effect of a specific inhibitor of 11-HSD-1 on metabolic abnormalities associated with obesity, particularly diabetes mellitus. The results are complex and difficult to interpret. Our conclusion is that the presence of VAT intracellular hypercortisolism in human obesity is possible but unlikely.

A case-control study suggests that the CCR6 locus is not involved in the susceptibility to giant cell arteritis.

OBJECTIVES: Polymorphisms of the CC chemokine receptor 6 (CCR6) gene have been recently reported to be associated with a number of autoimmune diseases. We aimed to investigate the possible influence of CCR6 rs3093024 gene variant in the susceptibility to and clinical expression of GCA. METHODS: The CCR6 polymorphism rs3093024 was genotyped in a total of 463 Spanish patients diagnosed with biopsy-proven GCA and 920 healthy controls using a TaqMan® allelic discrimination assay. PLINK software was used for the statistical analyses. RESULTS: No significant association between this CCR6 variant and GCA was observed (p=0.42, OR=0.94, CI95% 0.79-1.10). Similarly, when patients were stratified according to the specific clinical features of GCA such as polymyalgia rheumatica, visual ischaemic manifestations or irreversible occlusive disease, no statistical significant difference was detected either between the case subgroups and the control set or between GCA patients with and without the specific features of the disease. CONCLUSIONS: Our results suggest that the CCR6 rs3093024 polymorphism may not play a relevant role in the GCA pathophysiology.

Herbarium macroalgae specimens reveal a rapid reduction of thallus size and reproductive effort related with climate change.

Understanding and forecasting the effects of climate changes on vulnerable species are leading concerns for ecologists and conservation biologists. Herbaria are invaluable for use in long-term data series, and one of the few available methods for quantifying biodiversity changes over large periods of time. Gelidium canariense is an endemic and habitat-forming macroalga of the Canary Islands that coexists with two other habitat-forming Gelidiales: G. arbuscula and Pterocladiella capillacea. This study assesses long-term changes in thallus size and reproductive effort of all specimens deposited in the Herbarium of Universidad de La Laguna of these three Gelidiales species. Also assessed were the effects of seawater temperature and increased incident light on net primary production (NPP), and the effects of extreme desiccation conditions on the relative water content and NPP of the three Gelidiales species. The length of the thallus of the endemic species G. canariense was halved during the past 40 years. The shortening of the thallus coincided with a significant decrease in the number of reproductive structures in both Gelidium species. These morphological changes coincide with a significant increase of the sea surface temperature, air temperature above sea surface and ultraviolet radiation in the studied area. The experiments have revealed the deleterious effects of extreme desiccation and extreme irradiance on all three species. Hence, these results suggest that air temperature and irradiance are related with these morphological changes over time in the habitat-forming Gelidium species and that are most likely compromising the survival of their populations which are already declining.

Modeling the migration of chemicals from food contact materials to food: The MERLIN-expo/VERMEER toolbox.

Evaluating the migration of chemicals from food contact materials (FCM) into food is a key step in the safety assessment of such materials. In this paper, a simple mechanistic model describing the migration of chemicals from FCM to food was combined with quantitative property-property relationships (QPPRs) for the prediction of diffusion coefficients and FCM-Food partition coefficients. The aim of the present study was to evaluate the performance of these operational models in the prediction of a chemical's concentration in food in contact with a plastic monolayer FCM. A comparison to experimental migration values reported in literature was conducted. Deterministic simulations showed a good match between predicted and experimental values. The tested models can be used to provide insights in the amount and the type of toxicological data that are needed for the safety evaluation of the FCM substance. Uncertainty in QPPRs used for describing the processes of both diffusion in FCM and partition at the FCM-Food interface was included in the analysis. Combining uncertainty in QPPR predictions, it was shown that the third quartile (75th percentile) derived from probabilistic calculations can be used as a conservative value in the prediction of chemical concentration in food, with reasonable safety factors.

Contributions of nuclear medicine to malignant musculoskeletal tumor disease in children.

A diagnosis of cancer is frightening at any age, but especially when the patient is a child. Only what is suspected can be diagnosed, only what is known or at least known to exist is suspected, but musculoskeletal tumors are infrequent and therefore very difficult to diagnose or treat. Probably due to their infrequency, the complexity of the radiological images, histopathological appearance, as well as the serious consequences due to inadequate biopsies and treatments, musculoskeletal tumor pathology requires clinical management that must be carried out by a group of specialists with specific training, allowing an adequate diagnosis, introduction of adjuvant therapies, as well as surgical treatment, making multidisciplinary treatment essential today. Imaging studies provide essential information on the nature of each lesion, its size, its anatomical location, the effect on the surrounding bone or soft tissues and the involvement of adjacent joints and neurovascular structures. In this article the authors will discuss the advances in nuclear medicine techniques (scintigraphy, SPECT/CT and PET/CT) and their usefulness in the staging of pediatric malignant musculoskeletal tumors, as well as in the assessment of response, follow-up, and diagnosis of recurrence.

A3C-GS: Adaptive Moment Gradient Sharing With Locks for Asynchronous Actor-Critic Agents.

We propose an asynchronous gradient sharing mechanism for the parallel actor-critic algorithms with improved exploration characteristics. The proposed algorithm (A3C-GS) has the property of automatically diversifying worker policies in the short term for exploration, thereby reducing the need for entropy loss terms. Despite policy diversification, the algorithm converges to the optimal policy in the long term. We show in our analysis that the gradient sharing operation is a composition of two contractions. The first contraction performs gradient computation, while the second contraction is a gradient sharing operation coordinated by locks. From these two contractions, certain short- and long-term properties result. For the short term, gradient sharing induces temporary heterogeneity in policies for performing needed exploration. In the long term, under a suitably small learning rate and gradient clipping, convergence to the optimal policy is theoretically guaranteed. We verify our results with several high-dimensional experiments and compare A3C-GS against other on-policy policy-gradient algorithms. Our proposed algorithm achieved the highest weighted score. Despite lower entropy weights, it performed well in high-dimensional environments that require exploration due to sparse rewards and those that need navigation in 3-D environments for long survival tasks. It consistently performed better than the base asynchronous advantage actor-critic (A3C) algorithm.

18F-FDG-PET/CT in SARS-CoV-2 infection and its sequelae.

In recent months, much of the scientific efforts have focused on research on SARSCoV-2 infection and its consequences in humans. Still, many aspects remain unknown. It is known that the damage caused by SARS-CoV-2 is multifactorial and that its extension goes beyond lung inflammation and the acute phase, with the appearance of numerous complications and sequelae. To date, knowledge about the usefulness of 18F-FDG-PET/CT in the acute phase has been limited to the incidental detection of SARS-CoV-2 unsuspected pneumonia. Recent studies have been appearing collecting the findings of 18F-FDG-PET/CT in long COVID-19 or persistent COVID-19 state as well as the alterations caused after mass vaccination of the population in the metabolic studies. This work aims to review the existing literature focusing on these three issues and to briefly present our own preliminary experience.

[18F-FDG-PET/CT in SARS-CoV-2 infection and its sequelae]. / 18F-FDG-PET/TC ante la infección por SARS-CoV-2 y sus secuelas.

In recent months, much of the scientific efforts have focused on research on SARSCoV-2 infection and its consequences in humans. Still, many aspects remain unknown. It is known that the damage caused by SARS-CoV-2 is multifactorial and that its extension goes beyond lung inflammation and the acute phase, with the appearance of numerous complications and sequelae. To date, knowledge about the usefulness of 18F-FDG-PET/CT in the acute phase has been limited to the incidental detection of SARS-CoV-2 unsuspected pneumonia. Recent studies have been appearing collecting the findings of 18F-FDG- PET/CT in long COVID-19 or persistent COVID-19 state as well as the alterations caused after mass vaccination of the population in the metabolic studies. This work aims to review the existing literature focusing on these three issues and to briefly present our own preliminary experience.

Functional image in soft tissue sarcomas: An update of the indications of 18F-FDG-PET/CT. / Imagen funcional en sarcomas de partes blandas: actualización de las indicaciones de la 18F-FDG-PET/TC.

Soft tissue sarcomas (STS) are a rare and heterogeneous group of tumors. They account for 1% of solid malignant tumors in adults and 7% in children and are responsible for 2% of cancer mortality. They require a multidisciplinary approach in centers with experience. This collaboration aims to update the scientific evidence to strengthen, together with clinical experience, the bases for the use and limitations of 18F-FDG-PET/CT in STSs. The general recommendations for the use of PET/CT in STS at present are summarized as the initial evaluation of soft tissue tumours when conventional image does not establish benignity with certainty and this determines the approach; in biopsy guiding in selected cases; in the initial staging, as additional tool, for rhabdomyosarcoma and STS of extremities or superficial trunk and head and neck tumours; in the suspicion of local recurrence when the CT or MRI are inconclusive and in the presence of osteosynthesis or prosthetic material and in assessment of therapy response to local/systemic therapy in stages ii/iii. In addition, PET/CT has the added value of being a surrogate marker of the histopathological response and it provides prognostic information, both in the baseline study and after treatment.

Vitamin D in diabetes mellitus-a new field of knowledge poised for D-velopment.

This commentary reviews the current state of knowledge regarding the role of vitamin D in the pathogenesis of diabetes mellitus. In type 1 diabetes mellitus or in adult onset latent autoimmune diabetes (LADA), vitamin D exhibits immunomodulatory actions, influencing the activity of lymphocytes and interleukins. In type 2 diabetes mellitus vitamin D appears to act through different mechanisms, affecting insulin secretion and insulin sensitivity through its effects on the beta cells, mediators of inflammation and parathyroid hormone. Much work remains to be done in this new field of knowledge before the role of vitamin D in the pathogenesis of diabetes mellitus is completely understood.

Mycobacterium abscessus infection in solid organ transplant recipients: report of three cases and review of the literature.

Mycobacterium abscessus is an ubiquitous organism found in the environment. This rapidly growing mycobacterium infrequently causes disease in humans; however, in immunocompromised hosts, disease can range from localized cutaneous lesions to disseminated infection. The organism is resistant to most antimycobacterial drugs and therapy can be limited by drug interactions. The exact incidence of M. abscessus infection among solid organ transplant (SOT) recipients is unknown; data are only available from previously reported cases in the literature. We describe 3 cases of M. abscessus infection in SOT recipients diagnosed within a 5-month period. One of the cases followed multi-visceral transplantation, the first such case to be reported in the literature. An epidemiological investigation did not reveal significant commonalities among the cases, and pulsed-field gel electrophoresis of genomic DNA of the case isolates confirmed their non-identity. All cases improved with antibiotic therapy, most notably with the new glycylcycline, tigecycline, along with surgical intervention in 2 of the cases. In addition, we review features and characteristics of M. abscessus infections in recipients of SOT reported in the literature from 1992 to 2008 and summarize some selected therapeutic concerns and issues related to treatment.

Peri-prostatovesicular smooth muscle tumors of undetermined malignant potential: a case report.

INTRODUCTION: Smooth muscle tumors of undetermined malignant potential (STUMPs) are atypical smooth muscle tumors, most of which derived from uterine tissue. STUMPs of male genitourinary system and of the male pelvic organs are uncommon. CASE DESCRIPTION: In this report, we describe the first case of peri-prostatovesicular STUMP that was treated with laparoscopic excision, in a young asymptomatic man. CONCLUSIONS: In most cases, the definitive diagnosis can be made only after surgical resection and accurate histological examination. The usefulness of adjuvant chemotherapy remains unclear, and a standardized follow-up protocol has not been described.

The ERICA Tool.

The ERICA Tool is a computerised, flexible software system that has a structure based upon the ERICA Integrated Approach to assessing the radiological risk to biota. The Tool guides the user through the assessment process, recording information and decisions and allowing the necessary calculations to be performed to estimate risks to selected animals and plants. Tier 1 assessments are media concentration based and use pre-calculated environmental media concentration limits to estimate risk quotients. Tier 2 calculates dose rates but allows the user to examine and edit most of the parameters used in the calculation including concentration ratios, distribution coefficients, percentage dry weight soil or sediment, dose conversion coefficients, radiation weighting factors and occupancy factors. Tier 3 offers the same flexibility as Tier 2 but allows the option to run the assessment probabilistically if the underling parameter probability distribution functions are defined. Results from the Tool can be put into context using incorporated data on dose-effects relationships and background dose rates.

[Study of physician satisfaction as a quality criterion in Nuclear Medicine]. / Estudio de satisfacción de facultativos como criterio de calidad en Medicina Nuclear.

OBJECTIVE: To determine the perception and satisfaction level of referring physicians requesting scans as final users of the Nuclear Medicine Department. MATERIAL AND METHODS: A self-administered questionnaire was designed; it was composed of 10 closed questions (5 categorised and 5 with numerical scale) and 3 open questions. The indicators evaluated were: physician's information about available tests, test indications and diagnostic information, accessibility, delay in the examination and reception of the diagnostic report, usefulness of diagnostic information and overall satisfaction with the department. Two hundred and fifteen questionnaires were sent. RESULTS: Seventy eight questionnaires were returned, so the response index was 36.3 %. The 44.6 % of physicians surveyed considered that they had sufficient information about the tests and 59.5 % were satisfied with the indications and diagnostic information. The accessibility was 7 or more out of 10 for 78.5 %. The 64.9 % of physicians considered the delay in performing examinations to be correct but the satisfaction was lower in the delay between performance and reception of the diagnostic report. The diagnostic information was considered useful by 81.9 % and relevant in the management of patients by 70.5 % of the participants surveyed. The overall satisfaction was > or = 7 out of 10 in 86.8 %. CONCLUSIONS: Overall satisfaction was high, although the level of knowledge about available tests and the delay between test performance and report reception could be improved.

[Usefulness of ventricular function values obtained using post-stress gated-SPECT in a diabetic population with clinical suspicion of ischaemic heart disease]. / Utilidad de los valores de función ventricular obtenidos mediante gated-SPECT post-estrés en población diabética con sospecha clínica de cardiopatía isquémica.

OBJECTIVE: To assess the clinical usefulness of left ventricular function values obtained using post-stress myocardial perfusion gated-SPECT in diabetic patients with suspected ischaemic heart disease (IHD). MATERIALS AND METHODS: Sixty-one patients with diabetes mellitus (DM), with clinical suspicion of IHD and no previous history of heart disease were studied. Ergometric or pharmacological post-stress myocardial perfusion gated-SPECT was performed on all patients. The relationship between the ejection fraction values and ventricular volumes, and the perfusion study results, final diagnosis, severity of the perfusion defects and the clinical evolution was studied. The mean follow-up time was 14 months. RESULTS; All the ventricular function values independently showed significant differences between the groups with a normal and pathological perfusion study, and between groups with a final diagnosis of IHD and non-IHD. After multivariate logistic regression, the end-diastolic volume (EDV) was the only value which showed a statistical association with the pathological perfusion study, its severity and the final diagnosis of IHD. No statistical association was observed between the ventricular function values and the occurrence of cardiac events. CONCLUSIONS: All the ventricular function values obtained by gated-SPECT added diagnostic information to the post-stress myocardial perfusion study in the diabetic population with suspected IHD; however, only EDV showed a statistical association with the pathological perfusion study, severity of defects and the final diagnosis of IHD.