[Analysis of the characteristics of HIV-1 molecular transmission network among people aged 50 years and above in Pengzhou city of Sichuan province].

Objective: To describe the characteristics of molecular transmission network of newly diagnosed HIV-1 infected patients, analyze their risk factors related to network access and provide a scientific basis for precise prevention of HIV infection. Methods: For 340 blood samples collected from confirmed HIV-1 infection cases aged ≥50 years in Pengzhou city of Sichuan province from April 2019 to August 2021, nested PCR amplification was used to amplify, clean up and splice clips the pol gene region. The phylogenetic tree was constructed by multi-sequence comparison to distinguish subtypes, and the pairwise genetic distance was calculated. When the genetic distance threshold was 0.90%, the number of clusters was the largest (41), and the molecular transmission network was constructed.The χ2 test and logistic regression analysis were performed.The software SPSS 19.0 was used for statistical analysis. Results: A total of 340 samples were successfully amplified (97.06%, 330/340) in 330 samples. 6 HIV-1 subtypes identified, including:CRF01_AE(56.67%,187/330), CRF07_BC(27.88%,92/330), B(11.21%,37/330), CRF08_BC(3.33%,11/330), CRF55_01B(0.61%,2/330) and C(0.30%,1/330).The network entry rate was 58.79% (194/330).The results of logistic regression analysis of the risk factors of HIV-1 molecular transmission network in the research subjects showed that compared with illiteracy, junior high school (OR=0.35, 95%CI:0.13-0.97) and high school/technical secondary school (OR=0.14, 95%CI: 0.02-0.97) had lower possibility of network entry. Compared with farmers, unknown occupations (OR=0.40,95%CI: 0.17-0.95) are less likely to enter the network .Compared with CRF01_AE, CRF07_BC (OR=0.20, 95%CI: 0.11-0.35) and CRF08_BC subtype (OR=0.09, 95%CI: 0.02-0.45) were less likely to enter the network. Conclusions: The sources of AIDS transmission among middle-aged and elderly people of rural areas are diversified in Pengzhou city of Sichuan province. AIDS intervention should focus on middle-aged and elderly farmers with low educational level, and strengthen detection and traceability investigation.

Synthesis and evaluation of (18)F-labeled choline analogs as oncologic PET tracers.

UNLABELLED: Elevated levels of choline (trimethyl-2-hydroxyethylammonium) and choline kinase (CK) activity in neoplasms have motivated the development of positron-labeled choline analogs for noninvasive detection of cancer using PET. The aim of this study was to further evaluate [(18)F]fluorocholine (fluoromethyl-dimethyl-2-hydroxyethylammonium [FCH]) as an oncologic probe in comparison with several other closely related molecules. METHODS: FCH, [(18)F]fluoromethyl-methylethyl-2-hydroxyethylammonium (FMEC), [(18)F]fluoroethyl-dimethyl-2-hydroxyethylammonium (FEC), and [(18)F]fluoropropyl-dimethyl-2-hydroxyethylammonium (FPC) were synthesized through [(18)F]fluoroalkylation reactions. In vitro phosphorylation rates of the (18)F-labeled choline analogs and [methyl-(14)C]choline (CH) were studied using yeast CK. Several choline radiotracers were also evaluated in cultured PC-3 human prostate cancer cells. Data on chemical stability, radiation dosimetry, and toxicity of FCH were obtained. PET studies with FCH were performed on a patient with prostate cancer and a patient with a brain tumor. RESULTS: FCH and FMEC revealed in vitro phosphorylation by CK that was similar to that of choline, whereas rates of phosphorylation of FEC and FPC were 30% (P < 0.01) and 60% (P < 0.01) lower, respectively. Accumulations of FCH, CH, and FPC in cultured PC-3 cancer cells were comparable, whereas uptake of FEC was approximately one fifth that of FCH. Dosimetry estimates using FCH biodistribution data in mice indicated that the kidneys are radiation-dose-critical organs for FCH. PET images of a patient with recurrent prostate cancer showed uptake of FCH in the prostatic bed and in metastases to lymph nodes. FCH PET showed uptake in malignancies in a patient with metastatic breast cancer. PET revealed FCH uptake in biopsy-proven recurrent brain tumor with little confounding uptake by normal brain tissues. CONCLUSION: The fluoromethyl choline analog FCH may serve as a probe of choline uptake and phosphorylation in cancer cells, whereas fluoroethyl (FEC) and fluoropropyl (FPC) analogs appear to have relatively poorer biologic compatibility. Preliminary PET studies on patients with prostate cancer and with breast cancer and brain tumor support further studies to evaluate the usefulness of FCH as an oncologic probe.