Publications by authors named "S Liang"

6,421 Publications

Development of a Triazolobenzodiazepine-Based PET Probe for Subtype-Selective Vasopressin 1A Receptor Imaging.

Pharmacol Res 2021 Sep 15:105886. Epub 2021 Sep 15.

Department of Radiology, Division of Nuclear Medicine and Molecular Imaging Massachusetts General Hospital and Harvard Medical School, 55 Fruit Street, Boston, Massachusetts 02114, United States. Electronic address:

Objectives: To enable non-invasive real-time quantification of vasopressin 1A (V1A) receptors in peripheral organs, we sought to develop a suitable PET probe that would allow specific and selective V1A receptor imaging in vitro and in vivo.

Methods: We synthesized a high-affinity and -selectivity ligand, designated compound 17. The target structure was labeled with carbon-11 and tested for its utility as a V1A-targeted PET tracer by cell uptake studies, autoradiography, in vivo PET imaging and ex vivo biodistribution experiments.

Results: Compound 17 (PF-184563) and the respective precursor for radiolabeling were synthesized in an overall yield of 49% (over 7 steps) and 40% (over 8 steps), respectively. An inhibitory constant of 0.9nM towards the V1A receptors was measured, while excellent selectivity over the related V1B, V2 and OT receptor (IC >10,000nM) were obtained. Cell uptake studies revealed considerable V1A binding, which was significantly reduced in the presence of V1A antagonists. Conversely, there was no significant blockade in the presence of V1B and V2 antagonists. In vitro autoradiography and PET imaging studies in rodents indicated specific tracer binding mainly in the liver. Further, the pancreas, spleen and the heart exhibited specific binding of [C]17 ([C]PF-184563) by ex vivo biodistribution experiments.

Conclusion: We have developed the first V1A-targeted PET ligand that is suitable for subtype-selective receptor imaging in peripheral organs including the liver, heart, pancreas and spleen. Our findings suggest that [C]PF-184563 can be a valuable tool to study the role of V1A receptors in liver diseases, as well as in cardiovascular pathologies.
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http://dx.doi.org/10.1016/j.phrs.2021.105886DOI Listing
September 2021

Tailoring morphologies of mesoporous polydopamine nanoparticles to deliver high-loading radioiodine for anaplastic thyroid carcinoma imaging and therapy.

Nanoscale 2021 Sep 17;13(35):15021-15030. Epub 2021 Sep 17.

Department of Nuclear Medicine, Xin Hua Hospital Affiliated To Shanghai Jiao Tong University School, 1665 Kongjiang Road, Shanghai 200092, China.

Anaplastic thyroid carcinoma (ATC), as one of the most aggressive human malignancies, cannot be cured by iodine (I) internal radiotherapy (RT) because the tumor cells cannot effectively take up I and are resistant to radiotherapy. In this study, a facile and simple method was proposed to synthesize mesoporous polydopamine nanoparticles (MPDA) and tailor their morphologies by component-adjusting Pluronic micelle-guided polymerization. Then, MPDA were used not only as nanocarriers to radiolabel I, but also as photothermal conversion agents for photothermal therapy (PTT) to promote RT. The iodine-labeling capacity and photothermal conversion efficiency of MPDA can be enhanced by optimizing their morphologies. It was found that MPDA NPs with a cerebroid pore channel structure (CPDA) showed the highest iodine-carrying capacity and a higher photothermal conversion efficiency as a result of their maximum specific surface area and unique morphology. In subsequent experiments and , our ATC animal models showed impressive therapeutic responses to CPDA-I NPs because of the synergistic effect of PTT and RT. Additionally, CPDA-I NPs can be utilized to obtain high-quality SPETC/CT images of tumors, which can guide clinical therapy for ATC. Considering their great biosafety, these radioiodine-labeled CPDA NPs may serve as a promising tool in combined therapy and diagnosis in ATC.
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http://dx.doi.org/10.1039/d1nr02892hDOI Listing
September 2021

Correlation between thyroid autoantibodies and cardiovascular disease in patients with stages 3-5 chronic kidney disease.

Ann Transl Med 2021 Aug;9(16):1301

Department of General Practice, The Third Affiliated Hospital of Southern Medical University, Guangzhou, China.

Background: Chronic kidney disease (CKD) is associated with thyroid disease and cardiovascular disease (CVD). To date, little is known about the association of thyroid autoantibodies with renal function or cardiac function in patients with CKD.

Methods: This is a descriptive cross-sectional study. Patients diagnosed with stages 3-5 CKD from January 2015 to May 2019 at our department were recruited. Routine medical history, general clinical data, and laboratory test indexes were collected for all patients. Echocardiography was performed by a trained echocardiographer to measure E in early diastole and A, E/A ratio, E' in early diastole, A' in end-diastole, E/E' ratio, and E'/A' ratio.

Results: A total of 1,164 patients with stages 3-5 CKD were included. Thyrotropin receptor antibody (TRAb) was significantly positively correlated with C-reactive protein (r=0.206, P<0.001). Thyroid peroxidase antibody (TPOAb) and TGAb titers in male diabetic patients were higher (r=0.137, P=0.023; r=0.159, P=0.011). In female patients, both TPOAb and TGAb were significantly negatively correlated with hemoglobin (r=-0.213, P=0.018; r=-0.188, P=0.019). The E/E' of patients who were TPOAb positive was higher than that in patients with TPOAb negative (r=0.181, P<0.001). LVEF in patients who were TPOAb positive was higher than that in patients with TPOAb negative (r=0.159, P=0.007). In addition, LVEF was significantly negatively correlated with TRAb (r=-0.112, P=0.026).

Conclusions: In patients with stages 3-5 CKD, AITD may increase the risk of CVD in CKD patients by affecting triglycerides levels, increasing the risk of anemia, and promoting micro-inflammation. Attention should be paid to female patients with high TPOAb and TGAb titers. The mean of E/E' in patients with stage 5 CKD was 16.89 in the present study. Women with TPOAb positive may be more likely to develop diastolic heart failure.
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http://dx.doi.org/10.21037/atm-21-3280DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8422116PMC
August 2021

An improved ant colony optimization algorithm based on context for tourism route planning.

PLoS One 2021 16;16(9):e0257317. Epub 2021 Sep 16.

School of Software, Henan University, Kaifeng, Henan, China.

To solve the problem of one-sided pursuit of the shortest distance but ignoring the tourist experience in the process of tourism route planning, an improved ant colony optimization algorithm is proposed for tourism route planning. Contextual information of scenic spots significantly effect people's choice of tourism destination, so the pheromone update strategy is combined with the contextual information such as weather and comfort degree of the scenic spot in the process of searching the global optimal route, so that the pheromone update tends to the path suitable for tourists. At the same time, in order to avoid falling into local optimization, the sub-path support degree is introduced. The experimental results show that the optimized tourism route has greatly improved the tourist experience, the route distance is shortened by 20.5% and the convergence speed is increased by 21.2% compared with the basic algorithm, which proves that the improved algorithm is notably effective.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0257317PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8445481PMC
September 2021

Terrorist Attacks Against Vaccinators: A Review.

Health Secur 2021 Sep 16. Epub 2021 Sep 16.

Stephen Y. Liang, MD, MPHS, is Associate Professor, Division of Infectious Diseases and Division of Emergency Medicine, Washington University School of Medicine, St. Louis, MO.

Vaccinators fulfill an important role in a nation's public health by reducing the burden of disease on the population. Understanding patterns of attack employed against vaccinators is important to determine how to protect them. We conducted a search of the Global Terrorism Database for terrorist attacks against vaccinators that occurred between the years 1970 and 2018. Using the search terms "hospital," "healthcare," "clinic," "doctor," "nurses," "vaccinators," and "vaccinations," 2,322 healthcare-related entries were identified. We then manually searched the dataset for incidents related to attacks on vaccinators, which resulted in the identification of 133 attacks against vaccinators. The majority (128 out of 133) of attacks occurred during or after 2010. Every attack except one has occurred in the Middle East, South Asia, or sub-Saharan Africa. Pakistan has seen the most attacks against vaccinators, with 112 incidents recorded. Vaccinators continue to be vulnerable to terrorist attacks. Protection of healthcare personnel during mass vaccination efforts is critical so that they can continue their life saving mission.
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http://dx.doi.org/10.1089/hs.2021.0078DOI Listing
September 2021
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