Understanding suicidal ideation disparity between sexual minority and heterosexual Chinese young men: a multiple mediation model of social support sources, self-esteem, and depressive symptoms.

Objectives: Although sexual minorities have reported higher levels of suicidal ideation than heterosexuals across cultures, the role of various psychosocial factors underlying this disparity among young men has been understudied, particularly in China. This study examined the multiple mediating effects of psychosocial factors between sexual orientation and suicidal ideation in Chinese sexual minority and heterosexual young men. Methods: 302 Chinese cisgender men who identified as gay or bisexual, and 250 cisgender heterosexual men (n=552, aged 18-39 years) completed an online questionnaire measuring perceived social support, self-esteem, depressive symptoms, and suicidal ideation. Results: Young sexual minority men reported significantly higher suicidal ideation and lower social support than their heterosexual peers. Structural equation modelling revealed two multiple indirect pathways. One pathway indicated that sexual orientation was indirectly related to suicidal ideation via family support and depressive symptoms. Another pathway indicated that sexual orientation was indirectly related to suicidal ideation via support from friends, self-esteem, and depressive symptoms. Conclusions: This study is among the first to examine the potentially cascading relationships between sexual orientation and psychosocial factors with suicidal ideation in a Chinese sample of young men. The findings highlight several promising psychosocial targets (i.e., improving family/friend support and increasing self-esteem) for suicide interventions among sexual minority males in China.

Tumor-to-blood ratio for assessment of fibroblast activation protein receptor density in pancreatic cancer using [68Ga]Ga-FAPI-04.

PURPOSE: [68Ga]Ga-FAPI PET/CT has been widely used in clinical diagnosis and radiopharmaceutical therapy. In this study, tumor-to-blood ratio (TBR) was evaluated as a powerful tool for semiquantitative assessment of [68Ga]Ga-FAPI-04 tumor uptake and as an effective index for tumors with high FAP expression in theranostics. METHODS: Nine patients with pancreatic cancer underwent a 60-min dynamic PET/CT scan by total-body PET/CT (with a long AFOV of 194 cm) after injection of [68Ga]Ga-FAPI-04. After dynamic PET/CT scan, three patients received chemotherapy and underwent the second dynamic scan to evaluate treatment response. Time-activity curves (TACs) were obtained by drawing regions of interest for primary pancreatic lesions and metastatic lesions. The lesion TACs were fitted using four compartment models by the software PMOD PKIN kinetic modeling. The preferred pharmacokinetic model for [68Ga]Ga-FAPI-04 was evaluated based on the Akaike information criterion. The correlations between simplified methods for quantification of [68Ga]Ga-FAPI-04 (SUVs; tumor-to-blood ratios [TBRs]) and the total distribution volume (Vt) estimates obtained from pharmacokinetic analysis were calculated. RESULTS: In total, 9 primary lesions and 25 metastatic lesions were evaluated. The reversible two-tissue compartment model (2TCM) was the most appropriate model among the four compartment models. The total distribution volume Vt values derived from 2TCM varied significantly in pathological lesions and background regions. A strong positive correlation was observed between TBRmean and Vt from the 2TCM model in pathological lesions (R2=0.92, P<0.001). The relative difference range for TBRmean was 2.1% compared to the reduction rate of Vt in the patients who were treated with chemotherapy. CONCLUSIONS: A strong positive correlation was observed between TBRmean and Vt for [68Ga]Ga-FAPI-04. TBRmean reflects FAP receptor density better than SUVmean and SUVmax, and would be the preferred measurement tool for semiquantitative assessment of [68Ga]Ga-FAPI-04 tumor uptake and as a means for evaluating treatment response.

Preoperative three-dimensional versus two-dimensional evaluation in assessment of patients undergoing major liver resection for hepatocellular carcinoma: a propensity score matching study.

BACKGROUND: Compared with 2D evaluation, 3D evaluation possesses the virtues of displaying spatial anatomy of intrahepatic blood vessels and its relations to tumors, and enabling calculation of liver volumes, thus facilitating preoperative surgery planning. METHODS: The objective of this study is to study whether preoperative 3D (three-dimensional) evaluation produced better long-term overall survival (OS) outcomes compared to the traditional 2D (two-dimensional) evaluation in patients who underwent major hepatectomy for hepatocellular carcinoma (HCC). This retrospective study matched patients who underwent preoperative 2D evaluation with those who underwent preoperative 3D evaluation in a 1:1 ratio using propensity score matching. The primary endpoints were long-term survival outcomes in the two groups after major hepatectomy for HCC. RESULTS: Of the 248 patients in each of the 2 matched groups, the baseline characteristics were comparable. The median follow-up for all patients was 36 months (range, 0-40 months). The 3-year OS of patients in the PSM cohort was 38.5%. Compared with the 2D Group, patients in the 3D Group had a better OS rate (HR 0.722, 95% CI: 0.556-0.938, P=0.015) and disease-free survival (DFS) rate (HR 0.741, 95% CI: 0.590-0.929, P=0.009). The 3-year OS and DFS rate for the 3D Group versus the 2D group were 58.9% and 44.0% versus 47.4% and 33.1%, respectively. CONCLUSIONS: 3D preoperative evaluation resulted in significantly better intermediate-term (3-year) overall survival rate than the traditional 2D evaluation.

Disparity in depressive symptoms between heterosexual and sexual minority men in China: The role of social support.

Accumulating evidence suggests that sexual minorities experience elevated levels of depressive symptoms compared to heterosexuals in Western countries. Still, little is known about whether there is any difference in depressive symptoms between sexual minority men and heterosexual men in China. This study investigated the differences in depressive symptoms and social support between 302 Chinese sexual minority men and 249 heterosexual men. The association between depressive symptoms, social support and sexual orientation was also explored. Our results indicated that Chinese sexual minority men have more depressive symptoms and perceived lower social support than heterosexual men. Overall, sexual orientation and social support both predicted depressive symptoms. Different from previous Western studies, in our results, social support fully mediates but does not moderate the relationship between sexual orientation and depressive symptoms in Chinese men. The current findings suggest that social support has a significant impact on depressive symptoms among Chinese sexual minority men, highlighting the unique role of social support in understanding depressive symptoms among Chinese sexual minority men. Providing more social support, as well as promoting accepting and positive environments, may lead to better adjustment in this population in China.

Synthesis and Evaluation of Ga-68-Labeled Rhein for Early Assessment of Treatment-Induced Tumor Necrosis.

PURPOSE: This study aimed to synthesize a necrosis-avid agent using rhein as a precursor and labeled with gallium-68 (Ga-68) for positron emission tomography/computed tomography (PET/CT) imaging, to evaluate response to anticancer treatment in a mouse model. PROCEDURES: 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA)-conjugated rhein was radiolabeled with Ga-68 to formulate [68Ga]DOTA-rhein. The in vitro stability of [68Ga]DOTA-rhein was assessed by radio-HPLC. Necrosis avidity was evaluated in a mouse model of muscle necrosis by microPET/CT imaging, biodistribution study, histochemical staining, and autoradiography studies. Murine tumor models with the subcutaneous implantation of S180 cell lines were generated for the evaluation of therapeutic effect. Tumor necrosis was induced by the treatment of combretastatin A4 disodium phosphate (CA4P), and microPET/CT imaging was performed at 1 h post tracer injection. DNA binding studies were conducted to explore the necrosis avidity mechanism of the tracer. RESULTS: [68Ga]DOTA-rhein exhibited a satisfactory yield, a radiochemical purity over 97 %, and a good serum stability. The uptakes of [68Ga]DOTA-rhein in necrotic muscles and tumors were significantly higher than those in normal muscles and tumors (P < 0.05). The results of autoradiography and histochemical staining were consistent with the selective uptake of the radiotracer in necrotic regions. MicroPET/CT images showed a high uptake of the tracer in necrotic muscles and necrotic tumors. DNA binding studies suggested that necrosis avidity correlated with DNA binding to a certain extent. CONCLUSIONS: Our results demonstrated that [68Ga]DOTA-rhein showed a prominent necrosis avidity and could be a useful probe for early assessment of response to anticancer therapy by PET/CT imaging.

Delayed 18F FDG PET/CT Imaging in the Assessment of Residual Tumors after Transurethral Resection of Bladder Cancer.

Background Delayed fluorine 18 (18F) fluorodeoxyglucose (FDG) PET/CT is used to diagnose bladder cancer. However, it remains difficult to determine whether a lesion with abnormal 18F FDG uptake is tumor residue or recurrence or if it is an inflammatory reaction in patients with bladder cancer after oncologic treatment. Purpose To determine the diagnostic performance of delayed 18F FDG PET/CT in the differentiation of residual tumors from postoperative inflammatory reactions in patients with bladder cancer after initial transurethral resection of bladder tumor (TURBT). Materials and Methods A retrospective clinical study between January 2015 and April 2018 was performed in 79 patients with bladder cancer who had undergone 18F FDG PET/CT within 1 month after initial TURBT. After PET/CT, all patients underwent a second surgery within 2 weeks to confirm the histologic nature of the suspicious lesion and to remove residual tumors. Uni- and multivariable analysis were used to identify predictive factors for residual bladder tumors. Results A total of 79 patients (61 men, 18 women; mean age, 63 years ± 11 [standard deviation]) were enrolled in this study. A total of 98 lesions was studied, 64 (65.3%) of which were residual tumors after initial TURBT. When compared with inflammatory reactions, residual tumors had higher mean standardized uptake value (SUVmean) (mean, 5.8 ± 2.0 vs 9.3 ± 5.4; P < .001), higher maximum standardized uptake value (SUVmax) (mean, 15.5 ± 9.8 vs 22.2 ± 13.6, P = .01), and greater lesion thickness (mean, 9.6 mm ± 4.1 vs 17.9 mm ± 11.1, P < .001) at 18F FDG PET/CT. SUVmean (odds ratio [OR], 1.2; 95% confidence interval [CI]: 1.0, 1.5; P = .049) and lesion thickness (OR, 1.2; 95% CI: 1.0, 1.3; P = .006 or OR, 1.2; 95% CI: 1.1, 1.3; P = .001) were identified as independent predictors for residual tumors with multivariable logistic regression analysis. On the basis of the threshold values of SUVmean and lesion thickness, we revealed a prediction rate of 37.5% (17 of 47), 85.4% (26 of 29), and 98.3% (21 of 22) for residual tumors in low-, moderate-, and high-risk subgroups, respectively. Conclusion Use of fluorine 18 fluorodeoxyglucose PET/CT to differentiate lesions after transurethral resection of bladder tumor indicates that higher mean standardized uptake values and greater lesion thickness are predictive factors for residual tumors in patients with bladder cancer after oncologic treatment. Published under a CC BY 4.0 license.

Assessment of stable isotope incorporation into recombinant proteins.

Stable isotope labeling combined with mass spectrometry has been widely used in a diverse set of applications in the biochemistry and biomedical fields. When stable isotope-labeled proteins are produced via metabolic labeling of cell culture, a comprehensive assessment of the labeling pattern is imperative. In this study, we present a set of mass spectrometry-based bioanalytical tools developed for quantitatively tracing the levels of the stable isotopes incorporated into the recombinant proteins (monoclonal antibodies and Fc fusion proteins expressed in different host systems) that include total mass analysis, peptide mapping analysis, and amino acid analysis. We show that these three mass spectrometry-based analytical methods have distinctive advantages and limitations and that they are mutually complementary in evaluating the quality of stable isotope-labeled proteins. In addition, we show that the analytical techniques developed here are powerful tools to provide valuable insights into studying cell metabolism and performing flux analysis during cell culture.

Is FDG PET/CT cost-effective for pre-operation staging of potentially operative non-small cell lung cancer? - From Chinese healthcare system perspective.

OBJECTIVES: The remarkable morbidity and mortality of lung cancer in the large population address major economic challenges to Chinese healthcare system. This study aims to assess the cost-effectiveness of fluorodeoxyglucose positron emission tomography (FDG PET)/CT for staging patients with non-small cell lung cancer (NSCLC) in China. METHODS: Management of potentially operative NSCLC was modeled on decision analysis employing data in China. The strategies compared were conventional CT staging (strategy A), additional PET/CT in all patients (strategy B) or only in patients with normal-sized lymph nodes on CT (strategy C). Published medical data for Chinese patients was extracted. The costs corresponded to reimbursement by Chinese public health provider in 2010. Uncertainly of employed parameters was calculated in sensitivity analysis. RESULTS: Taking strategy A as baseline, the incremental cost-effectiveness ratio (ICER) of strategy B was 23,800RMB ($3500) per life year saved, which was acceptable in views of a developing country as China; while strategy C exhibited some loss of life years. Sensitivity analysis suggested the ICER (B-A) was raised more remarkably by a deterioration of PET specificity than by that of its sensitivity. The ICER was turned negative by PET specificity lower than 0.79. Economically, PET cost was proportional to the ICER (B-A), and decrease of palliative therapy cost could reduce both the ICER and overall cost. CONCLUSIONS: The PET/CT strategy is potentially cost-effective for management of NSCLC in China. Patients with nodal-positive CT results are not suggested to be excluded from further PET/CT. Furthermore, maintaining high specificity of PET in clinical scenarios is crucial. Prospective trials are warranted to transfer these results into policy making.

Interactions of carbohydrates and proteins by fluorophore-assisted carbohydrate electrophoresis.

A sensitive,specific, and rapid method for the detection of carbohydrate-protein interactions is demonstrated by fluorophore-assisted carbohydrate electrophoresis (FACE). The procedure is simple and the cost is low. The advantage of this method is that carbohydrate-protein interactions can be easily displayed by FACE, and the carbohydrates do not need to be purified.