Improved Chemical and Radiochemical Synthesis of Neuropeptide Y Y2 Receptor Antagonist N-Methyl-JNJ-31020028 and Preclinical Positron Emission Tomography Studies.

Neuropeptide Y (NPY) is one of the most abundant peptides in the central nervous system of mammals and is involved in several physiological processes through NPY Y1, Y2, Y4 and Y5 receptors. Of those, the Y2 receptor has particular relevance for its autoreceptor role in inhibiting the release of NPY and other neurotransmitters and for its involvement in relevant mechanisms such as feeding behaviour, cognitive processes, emotion regulation, circadian rhythms and disorders such as epilepsy and cancer. PET imaging of the Y2 receptor can provide a valuable platform to understand this receptor's functional role and evaluate its potential as a therapeutic target. In this work, we set out to refine the chemical and radiochemical synthesis of the Y2 receptor antagonist N-[11C]Me-JNJ31020028 for in vivo PET imaging studies. The non-radioactive reference compound, N-Me-JNJ-31020028, was synthesised through batch synthesis and continuous flow methodology, with 43% and 92% yields, respectively. N-[11C]Me-JNJ-31020028 was obtained with a radiochemical purity > 99%, RCY of 31% and molar activity of 156 GBq/µmol. PET imaging clearly showed the tracer's biodistribution in several areas of the mouse brain and gut where Y2 receptors are known to be expressed.

Racemose neurocysticercosis presenting with thalamic stroke: A case report and literature review.

Racemose neurocysticercosis is an uncommon type of neurocysticercosis that represents a particularly aggressive infection. It is characterized by the presence of multiple confluent cysts within the subarachnoid space and it carries unique diagnostic challenges. Clinical manifestations include headache, cerebrovascular events, and life-threatening hydrocephalus. A 56-year-old female presented with sudden onset headache and right-sided hemisensory loss. Brain MRI revealed multiple cystic lesions in the subarachnoid space consistent with racemose neurocysticercosis and left thalamus acute lacunar infarct. This case report emphasizes the clinical importance, unique characteristics, and imaging features of racemose neurocysticercosis and its complications.

Metachronous lesions after gastric endoscopic submucosal dissection: first assessment of the FAMISH prediction score.

BACKGROUND: Surveillance after gastric endoscopic submucosal dissection (ESD) is recommended for all patients owing to the persistent risk of metachronous gastric lesions (MGLs). We developed and validated a prediction score to estimate MGL risk after ESD for early neoplastic gastric lesions, to define an individualized and cost-saving approach. METHODS: Clinical predictors and a risk score were derived from meta-analysis data. A retrospective, single-center, cohort study including patients with ≥ 3 years of standardized surveillance after ESD was conducted for score validation. Predictive accuracy of the score by the area under the receiver operating characteristic curve (AUC) was assessed and cumulative probabilities of MGL were estimated. RESULTS: The risk score (0-9 points) included six clinical predictors (scored 0-3): positive family history of gastric cancer, older age, male sex, corpus intestinal metaplasia, synchronous gastric lesions, and persistent Helicobacter pylori infection (FAMISH). The study population included 263 patients. The MGL rate was 16 %. The score diagnostic accuracy for predicting MGL at 3 years' follow-up, measured by the AUC, was 0.704 (95 %CI 0.603-0.806). At 3 years and a cutoff < 2, the score achieved maximal sensitivity and negative predictive value; 15 % of patients could be assigned to a low-risk group, in which the progression to MGL was significantly lower than for the high-risk group (P = 0.04). CONCLUSION: The FAMISH score might be a useful tool to accurately identify patients with low-to-intermediate risk for MGL at 3 years of follow-up who could have surveillance intervals extended to reduce the burden of care.

Osteosarcoma-Derived Exosomes as Potential PET Imaging Nanocarriers for Lung Metastasis.

Lung metastases represent the most adverse clinical factor and rank as the leading cause of osteosarcoma-related death. Nearly 80% of patients present lung micrometastasis at diagnosis not detected with current clinical tools. Herein, an exosome (EX)-based imaging tool is developed for lung micrometastasis by positron emission tomography (PET) using osteosarcoma-derived EXs as natural nanocarriers of the positron-emitter copper-64 (64 Cu). Exosomes are isolated from metastatic osteosarcoma cells and functionalized with the macrocyclic chelator NODAGA for complexation with 64 Cu. Surface functionalization has no effect on the physicochemical properties of EXs, or affinity for donor cells and endows them with favorable pharmacokinetics for in vivo studies. Whole-body PET/magnetic resonance imaging (MRI) images in xenografted models show a specific accumulation of 64 Cu-NODAGA-EXs in metastatic lesions as small as 2-3 mm or in a primary tumor, demonstrating the exquisite tropism of EXs for homotypic donor cells. The targetability for lung metastasis is also observed by optical imaging using indocyanine green (ICG)-labeled EXs and D-luciferin-loaded EXs. These findings show that tumor-derived EXs hold great potential as targeted imaging agents for the noninvasive detection of small lung metastasis by PET. This represents a step forward in the biomedical application of EXs in imaging diagnosis with increased translational potential.

Polyphenol Metabolite Pyrogallol-O-Sulfate Decreases Microglial Activation and VEGF in Retinal Pigment Epithelium Cells and Diabetic Mouse Retina.

(Poly)phenol-derived metabolites are small molecules resulting from (poly)phenol metabolization after ingestion that can be found in circulation. In the last decade, studies on the impact of (poly)phenol properties in health and cellular metabolism accumulated evidence that (poly)phenols are beneficial against human diseases. Diabetic retinopathy (DR) is characterized by inflammation and neovascularization and targeting these is of therapeutic interest. We aimed to study the effect of pyrogallol-O-sulfate (Pyr-s) metabolite in the expression of proteins involved in retinal glial activation, neovascularization, and glucose transport. The expression of PEDF, VEGF, and GLUT-1 were analyzed upon pyrogallol-O-sulfate treatment in RPE cells under high glucose and hypoxia. To test its effect on a diabetic mouse model, Ins2Akita mice were subjected to a single intraocular injection of the metabolite and the expression of PEDF, VEGF, GLUT-1, Iba1, or GFAP measured in the neural retina and/or retinal pigment epithelium (RPE), two weeks after treatment. We observed a significant decrease in the expression of pro-angiogenic VEGF in RPE cells. Moreover, pyrogallol-O-sulfate significantly decreased the expression of microglial marker Iba1 in the diabetic retina at different stages of disease progression. These results highlight the potential pyrogallol-O-sulfate metabolite as a preventive approach towards DR progression, targeting molecules involved in both inflammation and neovascularization.

Diarrhea as a form of presentation of medullary thyroid carcinoma.

A case is presented of a 57-year-old man consulting for chronic diarrhea. Based on subsequent findings (thyroid nodule and metastases), the possibility of metastatic medullary thyroid carcinoma (MTC) was raised. Thyroidectomy allowed diagnosing a multicentric left lobe MTC. MTC is a rare cause of diarrhea, but should be considered, especially in the presence of signs or symptoms of alarm or nonresponse to empirical therapy.

Guideline values and human risk assessment for the presence of anti-inflammatory drugs remaining in drinking water after lab scale treatment

This study aimed to determine whether the anti-inflammatory drugs that are most commonly consumed in Brazil, including diclofenac, ketoprofen, naproxen, indomethacin, ibuprofen and acetaminophen, are present in drinking water and to derive guideline values to characterize the human risk. These pharmaceuticals were quantified in surface waters by LC-MS/MS with solid phase extraction, both before and after conventional treatment on a laboratory scale, using a jar test assay. The methods used to quantify these drugs showed good results: the chromatographic analysis obtained correlation coefficients between 0.9952 and 0.9991, with limits of quantification of 0.5 ng.mL-1 - 50 ng.mL-1 and precision standard deviations (0.08 - 2.08). Only ketoprofen and ibuprofen were not completely removed through the jar test. Environmental samples were collected and handled by the same method; the values |for ketoprofen and ibuprofen after treatment were 18.67 - 19.65 ng.L-1 (±17%) and 166.70 - 244.73 ng.L-1 (±14%), respectively. Human risk was assessed by comparing the guideline values for each compound to the concentrations obtained in the environmental samples, considering the toxicological backgrounds, following WHO (2011) method. The results suggest that the concentrations of ketoprofen and ibuprofen found in drinking water do not pose a risk to human health, even with chronic consumption