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This letter to the editor discusses the case of a 58-year-old man with Acute Wernicke Encephalopathy who underwent PET/CT imaging. The imaging revealed increased uptake in the midbrain, medial thalamus, and periaqueductal gray matter, which contrasts with previously reported decreased uptake associated with Wernicke encephalopathy. Treatment with vitamin B1 injection resulted in clinical improvement, and follow-up imaging showed decreased FDG uptake in the cerebral lesion areas. The study suggests that PET/CT can reflect glucose metabolism changes in vital organs affected by thiamine deficiency in Acute Wernicke's encephalopathy. [Extracted from the article]

Novel strategies for diagnosing triple-negative breast cancer (TNBC) are essential for effective clinical treatment. Vascular endothelial growth factor receptor 2 (VEGFR2) and neuropilin-1 (NRP-1) are potential targets for tumor imaging agents. We designed and synthesized [99mTc]Tc-labeled heptapeptide (A7R) and its D-type peptide (DA7R) with high affinity and specificity for VEGFR2 and NRP-1 as novel single-photon emission computed tomography (SPECT) probes for TNBC imaging. The specificities of A7R and DA7R were first evaluated in vitro using flow cytometry and confocal microscopy and ex vivo using fluorescence imaging. Subsequently, A7R and DA7R were labeled with [99mTc]Tc through 6-hydrazino nicotinamide (HYNIC), and their radiochemical purities (RCPs) and stability in vitro were assessed. The imaging performance and biodistribution of [99mTc]Tc-HYNIC-A7R and [99mTc]Tc-HYNIC-DA7R were evaluated in TNBC mouse models. A7R and DA7R exhibited good TNBC cell-targeting abilities and were readily labeled with [99mTc]Tc through HYNIC. Both [99mTc]Tc-HYNIC-A7R and [99mTc]Tc-HYNIC-DA7R had high RCPs and stability in vitro, and their accumulation in tumor tissues in the TNBC models was evident, with fast blood clearance and favorable biodistribution. More importantly, [99mTc]Tc-HYNIC-DA7R showed better tumor-to-muscle ratios and lower renal uptake than [99mTc]Tc-HYNIC-A7R. These results suggest that both [99mTc]Tc-HYNIC-DA7R and [99mTc]Tc-HYNIC-A7R have substantial potential as probes for targeted SPECT imaging of TNBC, and the former may be considered for future clinical translation owing to its superior tumor imaging performance. [ABSTRACT FROM AUTHOR]

Certain receptors are often overexpressed during tumor occurrence and development and closely correlate with carcinogenesis. Owing to its overexpression on the cell membrane and cytoplasm of various tumors, plectin, which is involved in tumor proliferation, migration, and invasion, has been viewed as a promising target for cancer imaging. Hence, plectin-targeting agents have great potential as imaging probes for tumor diagnosis. In this study, we developed a [99mTc]Tc-labeled plectin-targeted peptide (PTP) as a novel single-photon emission computed tomography (SPECT) probe for tumor imaging and investigated its pharmacokinetics, biodistribution, and targeting ability in several types of tumor-bearing mouse models. The PTP had good biocompatibility and targeting ability to tumor cells in vitro and could be readily labeled with [99mTc]Tc after modification with the bifunctional chelator 6-hydrazino nicotinamide (HYNIC). Furthermore, the prepared [99mTc]Tc-labeled PTP ([99mTc]Tc-HYNIC-PTP) showed high radiochemical purity and excellent stability in vitro. In addition, favorable biodistribution, fast blood clearance, and clear accumulation of [99mTc]Tc-HYNIC-PTP in several types of tumors were observed, with a good correlation between tumor uptake and plectin expression levels. These results indicate the potential of [99mTc]Tc-HYNIC-PTP as a novel SPECT probe for tumor imaging. [ABSTRACT FROM AUTHOR]

This study was to investigate the synthesis and biological evaluation of [99mTc]Tc-labeled Buthus martensii Karsch Chlorotoxin ([99mTc]Tc-BmK CT) as a radiopharmaceutical for glioma single photon computed emission tomography (SPECT) imaging. The results showed that BmK CT peptide modified with a hexahistidine tag displayed good cytocompatibility in vitro, and could be efficiently radiolabeled with 99mTc via [99mTc]Tc-tricarbonyl chemistry. The [99mTc]Tc-BmK CT showed satisfactory radiochemical purity and stability in vitro, and could be developed as a probe for targeted SPECT imaging of glioma cells in vitro and in a tumor-bearing mouse model. Our data indicated that the synthesized [99mTc]Tc-BmK CT might be developed as a promising imaging agent for glioma diagnostic application. [ABSTRACT FROM AUTHOR]

Purpose of the Report: To explore the value of 18 F-labeled prostate-specific membrane antigen (PSMA-1007) positron emission tomography (PET)/computed tomography (CT), the maximum standardized uptake value (SUVmax) of the primary tumor, prostate PSMA-tumor volume (PSMA-TVp), and prostate total lesion PSMA (TL-PSMAp) for predicting prostate cancer (PCa) metastasis and follow-up evaluation in primary PCa lesions., Materials and Methods: 18 F-PSMA-1007 PET/CT data of 110 consecutive newly diagnosed PCa patients were retrospectively analyzed. Patients were divided into non-metastatic, oligometastatic, and extensive metastatic groups. The predictive power was assessed using the receiver operating characteristic curve. Multi-group one-way analysis of variance and post-hoc tests were used to compare the groups. Patients were monitored post-therapy to evaluate treatment effectiveness., Results: Among the 110 patients, 66.4% (73) had metastasis (29 oligometastatic, 44 extensive metastasis). AUCs for Gleason score (GS), total prostate-specific antigen(TPSA), SUVmax, TL-PSMAp, and PSMA-TVp were 0.851, 0.916, 0.834, 0.938, and 0.923, respectively. GS, TPSA, SUVmax, TL-PSMAp, and PSMA-TVp were significantly different among the groups. In the post-hoc tests, differences in GS, TPSA, SUVmax, TL-PSMAp, and PSMA-TVp between the non-metastatic and oligometastatic groups and non-metastatic and extensive metastatic groups were significant (P<0.010). Differences in TL-PSMAp and PSMA-TVp between oligometastatic and extensive metastatic groups were significant (P=0.039 and 0.015, respectively), while those among GS, TPSA, and SUVmax were not. TL-PSMAp and PSMA-TVp distinguished between oligometastatic and extensive metastases, but GS, TPSA, and SUVmax did not. In individuals with oligometastasis, the implementation of active treatment for both primary and metastatic lesions may result in a more favorable prognosis., Conclusions: 18 F-PSMA-1007 PET/CT volumetric parameters PSMA-TVp and TL-PSMAp can predict PCa oligometastasis., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Li, Chen, Wang, Yang, Yang, Zhao and Li.)

Triple-negative breast cancer (TNBC) is the most aggressive breast cancer subtype, with a high mortality rate. One of the main reasons for this poor prognosis is the failure of a specific diagnosis. As a tumor-homing and penetrating peptide, iRGD has not only the properties of binding to neuropilin-1 and integrin αvβ3 but also internalizing into TNBC cells. In this study, we designed and prepared 99m Tc-labeled iRGD ( 99m Tc-HYNIC-iRGD) as a single-positron emission computed tomography (SPECT) imaging probe and investigated its feasibility for the targeted diagnosis of TNBC. The results showed that the iRGD peptide had acceptable biocompatibility within the studied concentration range and could specifically bind to TNBC cells in vitro . The 99m Tc-HYNIC-iRGD was readily prepared with high radiochemical purity and stability. SPECT imaging of 99m Tc-HYNIC-iRGD in a TNBC tumor-bearing mouse model showed obvious tumor accumulation with rapid blood clearance and favorable biodistribution. Our findings indicate that this active-targeted strategy has great potential to be developed as a novel tool for TNBC imaging., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Yu, Su, Zhao, Yang, Zhu and Zhao.)

Introduction: Smart theranostic nanosystems own a favorable potential to improve internalization within tumor while avoiding nonspecific interaction with normal tissues. However, development of this type of theranostic nanosystems is still a challenge., Methods: In this study, we developed the iodine-131 ( 131 I)-labeled multifunctional polyethylenimine (PEI)/doxorubicin (DOX) complexes with pH-controlled cellular uptake property for enhanced single-photon emission computed tomography (SPECT) imaging and chemo/radiotherapy of tumors. Alkoxyphenyl acylsulfonamide (APAS), a typical functional group that could achieve improved cellular uptake of its modified nanoparticles, was utilized to conjugate onto the functional PEI pre-modified with polyethylene glycol (PEG) with terminal groups of monomethyl ether and N-hydroxysuccinimide (mPEG-NHS), PEG with terminal groups of maleimide and succinimidyl valerate (MAL-PEG-SVA) through sulfydryl of APAS and MAL moiety of MAL-PEG-SVA. This was followed by conjugation with 3-(4'-hydroxyphenyl)propionic acid-OSu (HPAO), acetylating leftover amines of PEI, complexing DOX and labeling 131 I to generate the theranostic nanosystems., Results: The synthesized theranostic nanosystems exhibit favorable water solubility and stability. Every functional PEI can complex approximately 12.4 DOX, which could sustainably release of DOX following a pH-dependent manner. Remarkably, due to the surface modification of APAS, the constructed theranostic nanosystems own the capacity to achieve pH-responsive charge conversion and further lead to improved cellular uptake in cancer cells under slightly acidic condition. Above all, based on the coexistence of DOX and radioactive 131 I in the single nanosystem, the synthesized nanohybrid system could afford enhanced SPECT imaging and chemo/radioactive combination therapy of cancer cells in vitro and xenografted tumor model in vivo., Discussion: The developed smart nanohybrid system provides a novel strategy to improve the tumor theranostic efficiency and may be applied for different types of cancer., Competing Interests: The authors declare no conflicts of interest in this work., (© 2021 Zhu et al.)