Abnormal localized [¹⁸F]FDG accumulation in a Hoffman 3D brain phantom caused by Pseudomonas aeruginosa and Stenotrophomonas maltophilia

The version of record of this article, first published in European Journal of Nuclear Medicine and Molecular Imaging, is available online at Publisher’s website: https://doi.org/10.1007/s00259-024-06816-5.Hoffman 3D brain phantom was scanned to standardize the image quality in a clinical trial. Dynamic [¹⁸F]fluorodeoxyglucose positron emission tomography ([¹⁸F]FDG PET), which started 15 min after being filled with [¹⁸F]FDG (25 MBq), revealed an abnormally increasing accumulation of [¹⁸F]FDG in the left occipital cortex region at one hour. This abnormal accumulation showed an increasing trend (Fig. 1A, B). The presence of bacteria was suggested by the culture of scrabbed samples taken from the corresponding region in the phantom, later confirmed to be Pseudomonas aeruginosa and Stenotrophomonas maltophilia (Fig. 1C). Pseudomonas aeruginosa is an aerobic Gram-negative rod with a single flagellum at one end. It is a facultative anaerobic bacterium that generates ATP (adenosine triphosphate) necessary for growth by aerobic respiration and grows by oxidative degradation of glucose in the presence of oxygen [1]. Stenotrophomonas maltophilia is a non-fermentative Gram-negative bacterium that consumes proteins and peptides rather than sugars and carbohydrates as carbon and nutrient sources [2]. There have been several reports on the uptakes of [¹⁸F]FDG [3, 4]. We concluded that the abnormal accumulation was caused by FDG-avid bacterium, Pseudomonas aeruginosa and Stenotrophomonas maltophilia.It is preferable to use degassed tap water rather than purified or distilled water to prevent the growth of bacteria. Hoffman 3D brain phantom should be disassembled and completely dried after the scan, especially for multicenter clinical trials

Initial Evaluation of [18F]FAPI-74 PET for Various Histopathologically Confirmed Cancers and Benign Lesions

The 18F-labeled fibroblast activation protein inhibitor (FAPI) [18F]FAPI- 74 has the benefit of a higher synthetic yield and better image resolution than 68Ga-labeled FAPI. We preliminarily evaluated the diagnostic performance of [18F]FAPI-74 PET in patients with various histopathologically confirmed cancers or suspected malignancies. Methods: We enrolled 31 patients (17 men and 14 women) with lung cancer (n = 7), breast cancer (n = 5), gastric cancer (n = 5), pancreatic cancer (n = 3), other cancers (n = 5), and benign tumors (n = 6). Twenty-seven of the 31 patients were treatment-naïve or preoperative, whereas recurrence was suspected in the remaining 4 patients. Histopathologic confirmation was obtained for the primary lesions of 29 of the 31 patients. In the remaining 2 patients, the final diagnosis was based on the clinical course. [18F]FAPI-74 PET scanning was performed 60min after the intravenous injection of [18F]FAPI-74 (240631 MBq). The [18F]FAPI-74 PET images were compared between the primary or local recurrent lesions of malignant tumors (n = 21) and nonmalignant lesions (n 5 8: type-B1 thymomas, granuloma, solitary fibrous tumor, and postoperative or posttherapeutic changes). The uptake and number of detected lesions on [18F]FAPI-74 PET were also compared with those on [18F]FDG PET for available patients (n = 19). Results: [18F]FAPI-74 PET showed higher uptake in primary lesions of various cancers than in nonmalignant lesions (median SUVmax, 9.39 [range, 1.83-25.28] vs. 3.49 [range, 2.21-15.58]; P = 0.053), but some of the nonmalignant lesions showed high uptake. [18F]FAPI-74 PET also showed significantly higher uptake than [18F]FDG PET (median SUVmax, 9.44 [range, 2.50-25.28] vs. 5.45 [range, 1.22-15.06] in primary lesions [P 5 0.010], 8.86 [range, 3.51-23.33] vs. 3.84 [range, 1.01-9.75] in lymph node metastases [P 5 0.002], and 6.39 [range, 0.55-12.78] vs. 1.88 [range, 0.73-8.35] in other metastases [P 5 0.046], respectively). In 6 patients, [18F]FAPI-74 PET detected more metastatic lesions than [18F]FDG PET. Conclusion: [18F]FAPI-74 PET showed higher uptake and detection rates in primary and metastatic lesions than did [18F]FDG PET. [18F]FAPI-74 PET is a promising novel diagnostic modality for various tumors, especially for precise staging before treatment, including characterization of tumor lesions before surgery. Moreover, 18F-labeled FAPI ligand might serve a higher demand in clinical care in the future.This research was originally published in JNM. Tadashi Watabe, Sadahiro Naka, Mitsuaki Tatsumi et.al. Initial Evaluation of [18F]FAPI-74 PET for Various Histopathologically Confirmed Cancers and Benign Lesions. J Nucl Med. 2023, 64(8), 1225-1231. © SNMMI

Epithelioid granuloma mimicking lung cancer showed intense uptake on [18F]FAPI-74 PET

The version of record of this article, first published in European Journal of Nuclear Medicine and Molecular Imaging, is available online at Publisher’s website: https://doi.org/10.1007/s00259-023-06478-

Differential regulation of diacylglycerol kinase isoform in human failing hearts

Evidence from several studies indicates the importance of Gαq protein-coupled receptor (GPCR) signaling pathway, which includes diacylglycerol (DAG), and protein kinase C, in the development of heart failure. DAG kinase (DGK) acts as an endogenous regulator of GPCR signaling pathway by catalyzing and regulating DAG. Expressions of DGK isoforms α, ε, and ζ in rodent hearts have been detected; however, the expression and alteration of DGK isoforms in a failing human heart has not yet been examined. In this study, we detected mRNA expressions of DGK isoforms γ, η, ε, and ζ in failing human heart samples obtained from patients undergoing cardiovascular surgery with cardiopulmonary bypass. Furthermore, we investigated modulation of DGK isoform expression in these hearts. We found that expressions of DGKη and DGKζ were increased and decreased, respectively, whereas those of DGKγ and DGKε remained unchanged. This is the first report that describes the differential regulation of DGK isoforms in normal and failing human hearts

Cardiac tamponade caused by acute coxsackievirus infection related pericarditis complicated by aortic stenosis in a hemodialysis patient: a case report

Abstract Background Pericardial effusion is observed in the majority of viral pericarditis cases; however, viral pericarditis accompanied by a large effusion resulting in cardiac tamponade is rare. Case presentation Here, we report the case of a 75-year-old hemodialysis patient with acute viral pericarditis complicated by aortic stenosis. The patient was referred with a diagnosis of aortic stenosis and pericardial effusion. The pericardial effusion had increased during the preoperative examinations, and the inflammatory reaction had progressed. We decided to abort the surgical intervention and start oral administration of anti-inflammatory agents. We subsequently performed a pericardiocentesis. High antibody titers to coxsackievirus were noted in the pericardial effusion. Since no recurrence of the pericardial effusion was observed, the patient underwent an aortic valve replacement 2 months later. The pericardium completely adhered to the heart. Pathological examination of the pericardium showed fibrous pericarditis without active inflammation. Conclusions Here, we successfully treated a hemodialysis case with severe aortic stenosis complicated by cardiac tamponade and worsened by acute viral pericarditis. We waited for the pericarditis to resolve after administering anti-inflammatory agents and performed pericardial drainage before carrying out aortic valve replacement. The perioperative course of our case was unique and suggestive

Delayed and selective motor neuron death after transient spinal cord ischemia: A role of apoptosis?

AbstractObjective: The mechanism of spinal cord injury has been thought to be related to tissue ischemia, and spinal motor neuron cells are suggested to be vulnerable to ischemia. We hypothesized that delayed and selective motor neuron death is apoptosis. Methods: Thirty-seven Japanese domesticated white rabbits weighing 2 to 3 kg were used in this study and were divided into two subgroups: a 15-minute ischemia group and a sham control group. Animals were allowed to recover at ambient temperature and were killed at 8 hours, and 1, 2, 4, and 7 days after reperfusion (n = 3 at each time point). By means of this model, cell damage was histologically analyzed. Detection of ladders of oligonucleosomal DNA fragment was investigated with gel electrophoresis up to 7 days of the reperfusion. Immunocytochemistry, in situ terminal deoxynucleotidyl transferase–mediated deoxyuridine triphosphate–biotin nick-end labeling staining was also performed. Results: After 15 minutes of ischemia, most of the motor neurons showed selective cell death at 7 days of reperfusion. Typical ladders of oligonucleosomal DNA fragments were detected at 2 days of reperfusion. Immunocytochemistry showed in situ terminal deoxynucleotidyl transferase–mediated deoxyuridine triphosphate–biotin nick-end staining was detected at 2 days of reperfusion selectively in the nuclei of motor neurons. Conclusion: These results suggest that delayed and selective death of the motor neuron cells after transient ischemia may not be necrotic but rather predominantly apoptotic. (J Thorac Cardiovasc Surg 1998;115:1310-5

One‐Dimensionally Arranged Quantum‐Dot Superstructures Guided by a Supramolecular Polymer Template

Colloidal quantum dots (QDs) exhibit important photophysical properties, such as long-range energy diffusion, miniband formation, and collective photoluminescence, when aggregated into well-defined superstructures, such as three-dimensional (3D) and two-dimensional (2D) superlattices. However, the construction of one-dimensional (1D) QD superstructures, which have a simpler arrangement, is challenging; therefore, the photophysical properties of 1D-arranged QDs have not been studied previously. Herein, we report a versatile strategy to obtain 1D-arranged QDs using a supramolecular polymer (SP) template. The SP is composed of self-assembling cholesterol derivatives containing two amide groups for hydrogen bonding and a carboxyl group as an adhesion moiety on the QDs. Upon mixing the SP and dispersed QDs in low-polarity solvents, the QDs self-adhered to the SP and self-arranged into 1D superstructures through van der Waals interactions between the surface organic ligands of the QDs, as confirmed by transmission electron microscopy. Furthermore, we revealed efficient photoinduced fluorescence resonance energy transfer between the 1D-arranged QDs by an in-depth analysis of the emission spectra and decay curves