How international organizations can support the development of cardio-oncology in the Latin American and the Caribbean region.

Health problems in the Latin American and the Caribbean (LAC) region are highly concentrated on non-communicable diseases, being cardiovascular diseases (CVDs) and cancer the leading causes of death. Different countries of the region are at different stages of development in addressing CVDs and cancer. Opportunities for training and continuing education in cardio-oncology, as well as active cardio-oncology groups, are primarily limited to large academic institutions in major metropolitan areas. In addition, the development of advanced imaging modalities in LAC faces challenges such as the high cost of equipment, a lack of equipment maintenance and service, as well as insufficient specific training for both imaging specialists and referring clinicians. To contribute to the implementation of actionable strategies ensuring equitable access to care for all, international organizations, such as the International Atomic Energy Agency (IAEA), offer support for the regional development of health projects that address educational needs. In this context, a new IAEA regional cooperation project for LAC titled 'Strengthening of regional capacities on the use of Nuclear Medicine techniques in a Cardio-oncology multimodality approach in patients with cancer' will be developed during 2024-2025. The experience of some centres, as well as national experiences in certain countries of the region, that have been previously involved in other regional projects, can be leveraged for the benefit of the entire region. We present a proposed road map for cross-institutional/countries collaboration in the development of cardio-oncology in the LAC region, contributing to decreasing the barriers to the growth of the subspecialty.

18 F-FDG PET/CT Unveils Coexistent Myelomatous Hepatosplenic and Thyroid Cartilage Involvement : A Rare Presentation in Multiple Myeloma.

ABSTRACT: Extramedullary myelomatous disease is an aggressive condition where clonal plasma cells proliferate outside the bone marrow, allowing independent survival. This state is generally associated with negative outcomes. A 65-year-old woman presented with progressive bilateral hypochondrial pain, was initially misattributed to an inflammatory etiology, and was consequently managed with corticosteroid therapy. A bone marrow biopsy was offered after further deterioration confirming plasma cell myeloma. Afterward, 18 F-FDG PET/CT revealed medullary and extramedullary hepatosplenic and thyroid cartilage involvement, concluding an overall picture of an atypical and extensive extramedullary myelomatous disease.

The Diagnostic and Predictive Value of 18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography in Laryngeal Squamous Cell Carcinoma.

This retrospective study examines the diagnostic accuracy of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) and neck magnetic resonance imaging (MRI) in detecting nodal metastasis for patients with laryngeal squamous cell carcinoma (LSCC) and assesses the predictive values of metabolic and structural features derived from 18F-FDG PET/CT. By involving 66 patients from 2014 to 2021, the sensitivity and specificity of both modalities were calculated. 18F-FDG PET/CT outperforms neck MRI for nodal disease detection, with 89% sensitivity, 65% specificity, and 77% accuracy for nodal metastasis (p = 0.03). On the other hand, neck MRI had 66% sensitivity, 62% specificity, and 64% accuracy. Approximately 11% of patients witnessed a change in their therapy intent when relying on 18F-FDG PET/CT nodal staging results. Analyzing the cohort for PET-derived metabolic and morphological parameters, a total of 167 lymph nodes (LN) were visualized. Parameters such as the LN maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), total lesion glycolysis (TLG), and LN size were computed. Logistic regression and receiver operating characteristic (ROC) analyses were performed. Among the 167 identified cervical LNs, 111 were histopathologically confirmed as positive. ROC analysis revealed the highest area under the curve for LN MTV (0.89; p < 0.01), followed by LN size (0.87; p < 0.01). Both MTV and LN size independently predicted LN metastasis through multivariate analysis. In addition, LN MTV can reliably predict false-positive LNs in preoperative staging, offering a promising imaging-based approach for further exploration.

Current status of nuclear cardiology practice in Latin America and the Caribbean, in the era of multimodality cardiac imaging approach: 2022 update.

Cardiovascular diseases (CVDs) are the leading cause of mortality in Latin America and the Caribbean (LAC), with the risk in men being slightly higher than in women. The coronavirus disease 2019 (COVID-19) pandemic caused a significant reduction in the number of cardiac diagnostic procedures globally and in particular in LAC. Nuclear cardiology is available in the region, but there is variability in terms of existing technology, radiopharmaceuticals, and human resources. In the region, there are 2385 single photon emission computed tomography (SPECT) and 315 PET scanners, Argentina and Brazil have the largest number. There is an increasing number of new technologies such as cadmium-zinc-telluride (CZT) cardiac-dedicated gamma cameras, SPECT/computed tomography (CT), and PET/CT. All countries performed myocardial perfusion imaging studies, mainly gated-SPECT; the rest are multi-gated acquisition, mainly for cardiac toxicity; detection of viability; rest gated SPECT in patients with dilated cardiomyopathy, and bone-avid tracer cardiac scintigraphy for transthyretin cardiac amyloidosis diagnosis. Regarding other non-nuclear cardiac imaging modalities, Argentina, Colombia, and Chile have the highest ratio of CT scanners, while Brazil, Argentina, and Chile show the highest ratio of MRI scanners. The development of nuclear cardiology and other advanced imaging modalities is challenged by the high cost of equipment, lack of equipment maintenance and service, insufficient-specific training both for imaging specialists and referring clinicians, and lack of awareness of cardiologists or other referring physicians on the clinical applications of nuclear cardiology. Another important aspect to consider is the necessity of implementing cardiac imaging multimodality training. A joint work of nuclear medicine specialists, radiologists, cardiologists, and clinicians, in general, is mandatory to achieve this goal. National, regional, and international cooperation including support from scientific professional societies such as the American Society of Nuclear Cardiology and Latin American Association of Biology and Nuclear Medicine Societies, cardiological societies, and organizations such as the International Atomic Energy Agency, and Pan American Health Organization, as well as government commitment are key factors in the overall efforts to tackle the burden of cardiovascular diseases in the region.

Antioxidant Properties and Protective Effects of Some Species of the Annonaceae, Lamiaceae, and Geraniaceae Families against Neuronal Damage Induced by Excitotoxicity and Cerebral Ischemia.

This study aimed to compare the antioxidant activities of extracts obtained from three plant families and evaluate their therapeutic effect on strokes. Ethanol extracts were obtained from either the leaf or the aerial parts of plants of the families Annonaceae (Annona cherimola, A. diversifolia, A. muricata, A. purpurea, and A. reticulata), Lamiaceae (Salvia amaríssima and S. polystachya), and Geraniaceae (Geranium niveum and G. mexicanum). Extracts were analyzed in terms of hydroxyl radical (OH•), peroxyl radical (ROO•), and superoxide anion (O2•-). The efficiency of the extracts to prevent neuronal death induced by excitotoxicity was tested with the tetrazolium assay, the O2•- scavenging capacity was evaluated with the dihydroethidium dye, and the protective effect of the extracts with the highest antioxidant activity was tested on a stroke experimental model. The extracts' IC50 values (µg/mL) of scavenging varied from 98.9 to 155.04, 4.5 to 102.4, and 20.2 to 118.97 for OH•, ROO•, and O2•-, respectively. In the excitotoxicity model, Annonaceae extracts were highly cytotoxic while Lamiaceae and Geraniaceae reduced intracellular O2•- production and protect neurons against oxidative stress. Salvia polystachya reduced cerebral damage, as well as improved survival and behavior after ischemia. Our results encouraged the use of plant extracts as natural antioxidants to minimize neuronal injury following stroke.

Current status of nuclear cardiology practice in Latin America and the Caribbean.

The burden of cardiovascular diseases (CVDs) in the world is ever growing. They represent the first cause of death worldwide and in Latin America. Nuclear cardiology has a well-established role in the management of patient with CVDs and is being increasingly integrated into the healthcare systems in the region. However, there remains variability as to the infrastructure available across the countries, in terms of existing technology, radiopharmaceuticals, and human resources. The approximate number of gamma (γ) cameras in the region is 1348, with an average of 2.25 per million population; Argentina and Brazil having the largest number. Nearly 80% of the existing cameras are single-photon emission tomography (SPECT), of which 8% are hybrid SPECT-CT systems. Positron emission tomography technology is steadily increasing, and currently, there is an average of 0.25 scanners per million inhabitants, indicating that there is a potential to expand the capacities in order to cover the needs. Four countries have nuclear reactors for research purposes, which allow the production of technetium-99 m (Argentina, Chile, Mexico and Peru), while four (Argentina, Brazil, Cuba, and Mexico) assemble 99Mo-99mTc generators. As for the nuclear cardiology studies, about 80% of studies performed are gated SPECT myocardial perfusion imaging; less than 10% are multi-gated acquisition (mainly for evaluation of cardiac toxicity in cancer patients), and the other 10% correspond to other types of studies, such as viability detection, and adrenergic innervation studies with 123I-MIBG. Physical stress is preferred, when possible, based on the clinical condition of the patient. Regarding human resources, there is an average of 1.1 physicians and 1.3 technologists per γ camera, with 0.1 medical physicists and 0.1 radiopharmacists per center in the region. The future of nuclear cardiology in Latin America and the Caribbean is encouraging, with great potential and possibilities for growth. National, regional, and international cooperation including support from scientific societies and organizations such as International Atomic Energy Agency, American Society of Nuclear Cardiology, and Latin American Association of Biology and Nuclear Medicine Societies, as well as governmental commitment are key factors for the development of the specialty. A multimodality approach in cardiac imaging will contribute to a better management of patients with CVDs.

Murine cysticercosis model: influence of the infection time and the time of treatment on the cysticidal efficacy of albendazole and praziquantel.

In the search of new alternatives for neurocysticercosis treatment, Taenia crassiceps ORF strain cysticerci have been used instead of T. solium for in vitro studies. Up to date, the main criteria for the use of the murine cysticercosis model for drug efficacy evaluation have not been assessed. The aim of the present study was to evaluate the influence of two of the main variables related to the in vivo efficacy: the length of drug treatment and the starting time of treatment after experimental infection, using albendazole (ABZ) and praziquantel (PZQ) as test drugs. Additionally, the relationship between the number of cysts and the parasite weight was assessed. For the study, female BALB/c mice were experimentally infected with T. crassiceps cysts. Three different post-infection periods (10, 20 and 30 days) and three different lengths of treatment with ABZ or PZQ (10, 20 and 30 days) were selected. The efficacy of each treatment was evaluated by comparison with a control group. Our results show that for in vivo efficacy studies, the best time to start the drug treatment is 10 days post-infection and that a minimum of 20 days of treatment is required when ABZ or PZQ are used as positive control. Moreover, in this model the parasite weight can be used as a rapid tool to measure the in vivo drug activity.

Gestational undernourishment modifies the composition of skeletal muscle transverse tubule membranes and the mechanical properties of muscles in newborn rats.

BACKGROUND/AIMS: [corrected] Skeletal muscle (SM) constitutes more than 40% of the body weight in adulthood. Transports dietary glucose mainly through the insulin-dependent glucose transporter (Glut-4) located in the Transverse tubule membrane system (TT). The TT development ends shortly after birth. The TT membrane hosts the proteins involved in excitation-contraction coupling and glucose uptake. Glycaemic regulation through movement is a key function of fully developed skeletal muscle. In this study, we aimed to characterize the effect of gestational undernourishment (GUN) in rats GLUT-4 expression and on the protein/lipid content of the TT membranes. We also examined the effect of GUN on the mechanical properties of muscles as an indication of the metabolic condition of the SM at birth. METHODS: Isolated TT membrane from SM of GUN rats were used to study lipid/protein content and protein stability by differential scanning calorimetry. The effect of GUN on the SM mechanical properties was determined in isolated Extensor Digitorum Longus (EDL) muscle. RESULTS: We demonstrate that compared to control, GUN in the new-born produces; i) decreases body weight; ii) diminution in SM mass; iii) decreases the formation of TT membranes; iv) expresses TT membrane proteins with higher thermal stability. The TT membrane expression of GLUT-4 in GUN offspring was twice that of controls. The isolated EDL of GUN offspring was 20% stronger as measured by contractile force and more resistant to fatigue relative to controls. CONCLUSION: These results provide the first evidence of adaptive changes of the SM in new-borns exposed to severe gestational food restriction. The effects of GUN on muscle at birth are the first step toward detrimental SM metabolic function, contributing to the physiopathology of metabolic diseases in adulthood.

Resultados oncológicos y funcionales del tratamiento no quirúrgico comparado con el quirúrgico en los carcinomas epidermoides de orofaringe / Functional and oncological results of non-surgical vs surgical treatment in squamous cell carcinomas of the oropharynx

Introducción y objetivos: Los carcinomas de orofaringe son neoplasias agresivas habitualmente diagnosticadas en estadios avanzados, siendo su tratamiento óptimo controvertido. El objetivo de este estudio es comparar los resultados oncológicos y funcionales de pacientes tratados con radioterapia (±quimioterapia concomitante) con otros tratados mediante cirugía (±radioterapia complementaria). Métodos: Se realizó un estudio retrospectivo en 50 pacientes con carcinoma epidermoide de orofaringe tratados con radioterapia (más quimioterapia concomitante en casos avanzados) entre 1998 y 2008, comparándolos con pacientes con el mismo estadio y localización tratados con cirugía (más radioterapia complementaria en casos avanzados). Ambos grupos se clasificaron de la siguiente manera: 10% estadio I, 12% en estadio II, 16% en estadio III, 48% en estadio IVa y 14% en estadio IVb. Resultados: La supervivencia específica para la enfermedad a los 5 años fue del 33% para el grupo de radioterapia y del 52% para el grupo de cirugía (p = 0,17). En tumores en estadios I y II, esta supervivencia específica fue del 82% en los tratados con radioterapia y del 70% en los tratados con cirugía. En estadios III y IV la supervivencia era mayor en los pacientes tratados con cirugía (47 vs 17%). Los resultados funcionales fueron similares en ambos grupos, presentando mayor preservación anatómica y funcional de la laringe el grupo de radioterapia, mientras que el grupo quirúrgico obtuvo mejores resultados para la alimentación oral. Conclusiones: El pronóstico de los pacientes con carcinomas epidermoide de orofaringe es pobre. Los resultados oncológicos del tratamiento con radioterapia y cirugía son similares para los estadios I y II. En estadios III y IV la supervivencia es mayor en los pacientes tratados mediante cirugía. Los resultados funcionales son también similares en ambos grupos (AU)

Introduction and objectives: Squamous cell carcinomas of the oropharynx are aggressive tumours usually diagnosed at advanced stage. Their optimal treatment has not been established. The aim of this study was to compare the oncological and functional outcomes in patients with carcinomas of the oropharynx treated by radiotherapy (with chemotherapy in advanced stages) vs surgery (with radiotherapy in advanced stages). Methods: A retrospective study on 50 patients with squamous cell cancer of the oropharynx treated by radiotherapy (with or without chemotherapy) at our institution between 1998 and2008 was carried out. The oncological and functional results were compared with patients with same cancer location and stage treated by surgery (with or without radiotherapy). In both groups, the patients were classified as follows: 10% Stage I, 12% Stage II, 16% Stage III, 48%Stage IVa and 14% Stage IVb. Results: The 5-year disease-specific survival was 33% in the radiotherapy group and 52% in the surgical group (P=.17). Five-year disease-specific survival for Stage I and II patients was 82% in the radiotherapy group and 70% in the surgical group. In Stage III and IV disease, 5-year disease specific survival was higher in the surgical group (47% vs 17%). The functional results were similar; anatomical and functional preservation of the larynx was higher in the radiotherapy group but the successful return to oral food intake was higher in the surgical group. Conclusions: The prognosis of squamous cell carcinoma of the oropharynx is poor. Oncological results in Stages I and II were similar for radiotherapy and surgical treatments. In advanced stages, the prognosis was better in patients treated by surgery with or without radiotherapy. Functional results were similar in both treatment modalities (AU)

Functional and oncological results of non-surgical vs surgical treatment in squamous cell carcinomas of the oropharynx.

INTRODUCTION AND OBJECTIVES: Squamous cell carcinomas of the oropharynx are aggressive tumours usually diagnosed at advanced stage. Their optimal treatment has not been established. The aim of this study was to compare the oncological and functional outcomes in patients with carcinomas of the oropharynx treated by radiotherapy (with chemotherapy in advanced stages) vs surgery (with radiotherapy in advanced stages). METHODS: A retrospective study on 50 patients with squamous cell cancer of the oropharynx treated by radiotherapy (with or without chemotherapy) at our institution between 1998 and 2008 was carried out. The oncological and functional results were compared with patients with same cancer location and stage treated by surgery (with or without radiotherapy). In both groups, the patients were classified as follows: 10% Stage I, 12% Stage II, 16% Stage III, 48% Stage IVa and 14% Stage IVb. RESULTS: The 5-year disease-specific survival was 33% in the radiotherapy group and 52% in the surgical group (P=.17). Five-year disease-specific survival for Stage I and II patients was 82% in the radiotherapy group and 70% in the surgical group. In Stage III and IV disease, 5-year disease-specific survival was higher in the surgical group (47% vs 17%). The functional results were similar; anatomical and functional preservation of the larynx was higher in the radiotherapy group but the successful return to oral food intake was higher in the surgical group. CONCLUSIONS: The prognosis of squamous cell carcinoma of the oropharynx is poor. Oncological results in Stages I and II were similar for radiotherapy and surgical treatments. In advanced stages, the prognosis was better in patients treated by surgery with or without radiotherapy. Functional results were similar in both treatment modalities.

Connexin 36 is expressed in beta and connexins 26 and 32 in acinar cells at the end of the secondary transition of mouse pancreatic development and increase during fetal and perinatal life.

To identify when during fetal development connexins (Cxs) 26 (Cx26) 32 (Cx32), and 36 (Cx36) begin to be expressed, as well as to characterize their spatial distribution, real time polymerase chain reaction and immunolabeling studies were performed. Total RNA from mouse pancreases at 13 and 18 days postcoitum (dpc) and 3 days postpartum (dpp) was analyzed. In addition, pancreatic sections of mouse at 13, 14, 15, 16, 18 dpc and 3 dpp and of rat at term were double labeled with either anti-insulin or anti-α-amylase and anti-Cx26 or -Cx32 or -Cx36 antibodies and studied with confocal microscopy. From day 13 dpc, Cxs 26, 32, and 36 transcripts were identified and their levels increased with age. At 13-14 dpc, Cxs 26 and 32 were localized in few acinar cells, whereas Cx36 was distributed in small beta cell clumps. From day 14 dpc onwards, the number of labeled cells and relative immunofluorescent reactivity of all three Cxs at junctional membranes of the respective cell types increased. Cxs 26 and 32 colocalized in fetal acinar cells. In rat pancreas at term, a similar connexin distribution was found. Relative Cxs levels evaluated by immunoblotting also increased (two-fold) in pancreas homogenates from day 18 dpc to 3 dpp. The early cell specific, wide distribution, and age dependent expression of Cxs 26, 32, and 36 during fetal pancreas ontogeny suggests their possible involvement in pancreas differentiation and prenatal maturation.

F18-FDG-PET/CT in the evaluation of patients with suspected recurrent or persistent locally advanced cervical carcinoma.

BACKGROUND: Cervical cancer (CC) represents the second most common neoplasm and the third cause of death by cancer among women. Recurrent or persistent disease depends on the clinical stage, but can be as high as 70%. Positron emission tomography/computed tomography (PET/CT) is an image study that can detect increased glucose uptake in tumor tissues. MATERIAL AND METHODS: PET/CT was performed in patients with confirmed CC, who had been previously treated, who developed suspected symptoms of recurrence or persistent disease with or without evidence of disease on a CT scan. Sensitivity, specificity, predictive values from PET/CT, and CT scan were evaluated. RESULTS: Sixteen patients with a mean age of 47.2 years were included in the study from April 2007 to June 2008. Thirteen patients (81.2%) were symptomatic. PET/CT was positive in 14/16 (85.7%), of these, 12 True positive (TP) and two, False positive (FP); meanwhile another two cases were True negative (TN) (12.5%). Cervix, retroperitoneal, iliac, obturator, and mediastinal lymph nodes were the most common anatomic sites detected by PET/CT. Mean number of anatomic sites with high Fluoro-deoxy-D-glucose (FDG) uptake was two sites (range 1-7 sites). PET/CT and CT scan had 100 and 91.7% sensitivity, respectively. Specificity for both was 50%. Positive predictive value (PPV) was 85.4 and 84.6%, respectively. Negative predictive value (NPV) was 100 and 66%, respectively, and accuracy was 88 vs. 81%, respectively. CONCLUSIONS: PET/CT has the capability for detecting recurrent or persistent cervical cancer; it detects increased metabolic activity mainly in primary site or lymph nodes. Further PET/CT evaluation is required to confirm the real impact of this study on the early detection of CC recurrence.

Activity of topotecan given intravenously for 5 days every three weeks in patients with advanced non-small cell lung cancer pretreated with platinum and taxanes: a phase II study.

Topotecan, a semi-synthetic camptothecin analogue with topoisomerase I interaction, has shown to be an active agent in the treatment of advanced refractory lung cancer. This paper describes the authors' experience with this drug when used as a single agent in patients (pts) with advanced non-small cell lung cancer (NSCLC) refractory to platinum- and taxane-containing chemotherapy regimens. Thirty-five patients with NSCLC refractory to previous chemotherapy and KI ≥ 60% were included in the study. Their characteristics are as follows: median age of 52 years (range 43-69) and Karnofsky PS of 70 (60-80); 27 were male and 8 were female. Twenty-one (60%) patients had adenocarcinoma; eleven (31.4%), squamous cell, and three (8.5%), undifferentiated carcinoma. There was a median of two disease sites and two prior chemotherapy regimens. Topotecan was administered at a dose of 1.25 mg/m(2) I.V. daily for 5 days, repeated every 21 days until disease progression, maximal response, or intolerable toxicity. After 73 cycles, patients received a median of 2 treatment cycles (1-9). All patients except one were considered evaluable for toxicity; eight episodes (24%) of nausea/vomiting and two episodes (6%) of grade 1-2 asthenia, respectively, were reported. Four (12%) patients developed grade 1-2 anemia and two (6%) subjects suffered grade 3 anemia. Seven (21%) patients had grade 1-2 neutropenia and one (3%) presented grade 5 neutropenia. In 33 patients evaluable for activity of the 35 subjects included in the study; one (2.8%) presented a partial response; nine (25.7%) had stable disease, and 23 (65.7%) exhibited disease progression. Median time to progression and overall survival were 54 (12-210) and 70 (12-324) days, respectively. Intravenous topotecan at that dose and administration schedule displays scant activity in terms of response rate in individuals with advanced NSCLC previously treated with platinum and taxanes. The role and usefulness of chemotherapy in this setting warrants further investigation and confirmation through comparative studies.

Functional expression and subcellular localization of the taurine transporter TauT in murine neural precursors.

Taurine addition to cultured embryonic neural precursor cells (NPC) significantly increased cell proliferation [Hernández-Benítez et al., 2010]. The medium used for NPC growing and proliferation is a fetal serum-free medium, and therefore, NPC become taurine depleted. Addition of taurine to the cultured medium fully replenished the cell taurine pool, suggesting the functional expression of a taurine transporter (TauT) in these cells. In the present study, TauT in NPC was functionally characterized and its protein expression and the subcellular distribution of immunoreactivity were determined. ³H-taurine uptake in NPC could be separated into a non-saturable component and a Na(+)/Cl⁻-dependent, saturable component. The saturable component showed an apparent 2:1:1 Na(+)/Cl⁻/taurine stoichiometry, a V(max) of 0.39 ± 0.04 nmol/mg protein/min, and a K(m) of 21.7 ± 2.6 µM. TauT in NPC was strongly inhibited by hypotaurine and ß-alanine (92 and 79%, respectively) and reduced (71%) by γ-aminobutyric acid. TauT protein is expressed in NPC as a single band of about 70 kDa. Essentially all (98.8%) of the neurosphere-forming cells were positive to TauT immunoreactivity. Immunolocalization visualized by confocal microscopy localized TauT predominantly at the cell membrane. TauT was also found at the cytosol and only occasionally at the nuclear membrane. This study represents the first characterization of TauT in NPC.