Effect of 18F-DCFPyL PET on changes in management of patients with prostate cancer: a systematic review and meta-analysis.

Purpose: Prostate-specific membrane antigen (PSMA)-targeted imaging has gained increasing interest in its application in prostate cancer lesion detection. Compared with 68Galium (68Ga), 18Fluoride (18F)-labeled imaging agent has easier syntheses, lower price, and a longer half-time. 2-(3-{1-Carboxy-5-[(6-[18F]fluoro-pyridine-3-carbonyl)-amino]-pentyl}-ureido)-pentanedioic acid positron emission tomography (18F-DCFPyL PET) has been recently approved by the U.S. Food and Drug Administration. Several studies have proven its superiority to conventional imaging techniques in detecting prostate cancer lesions. However, the impact of 18F-DCFPyL PET on the management of patients with prostate cancer is not well established. Thus, we performed a systematic review and meta-analysis of available data to evaluate the impact of 18F-DCFPyL PET on the management of patients with prostate cancer. Methods: The PubMed, Embase, Scopus, and Cochrane databases were searched up to April 2024. Studies that reported the proportion of changes in management after 18F-DCFPyL PET was performed in patients with prostate cancer were included. The Grading of Recommendations Assessment, Development, and Evaluation system was used for the quality evaluation of the included studies. The proportion of changes in management was pooled using a random effects model. Meta-regression analyses were performed to assess the potential correlation between the PET positivity and management changes. Results: Fourteen studies (3,078 patients with prostate cancer) were included in our review and analysis. The pooled percentage of management changes was 43.5% (95% confidence interval [CI]: 33-54%). In patients with biochemical recurrent and for primary staging, the pooled percentage was 50% (95% CI: 39-60%) and 22% (95% CI: 15-29%), respectively. In the meta-regression analyses, PET positivity was detected as a significant predictor of management change (p = 0.0023). Conclusion: 18F-DCFPyL PET significantly affects the management of patients with prostate cancer. Higher PET positivity rate significantly correlated with a higher proportion of management changes in patients with prostate cancer. However, more studies are still needed to confirm the important role of 18F-DCFPyL PET in the management of prostate cancer. Systematic review registration: https://www.crd.york.ac.uk/PROSPERO/#myprospero, CRD42022339178.

Heterogeneous Uptake of 68 Ga-DOTATATE and 18 F-FDG in Initial Diagnosed Neuroendocrine Tumors Patients : Which Patients Are Suitable for Dual-Tracer PET Imaging?

PURPOSE: This study was designed to assess the uptake heterogeneity in neuroendocrine tumor (NET) patients at initial diagnosis with dual-tracer PET imaging and the staging changes and prognostic value it brings to explore the indication of the use of dual-tracer PET. METHODS: Fifty-one newly diagnosed patients with pathologically confirmed NET who underwent 18 F-FDG and 68 Ga-DOTATATE PET imaging between January 2020 and September 2022 were enrolled. Dual-tracer uptake patterns were classified into 3 groups: A. 68 Ga-DOTATATE positive and 18 F-FDG negative, B. 68 Ga-DOTATATE positive and 18 F-FDG positive, and C. 68 Ga-DOTATATE negative and 18 F-FDG positive. Descriptive statistics were used to evaluate the heterogeneity of dual-tracer uptake patterns among different grading (G) groups, between primary and metastatic lesions, and staging changes. Moreover, dual-tracer uptake patterns, grade, age, sex, and stage were compared with progression-free survival (PFS) by Cox regression. RESULTS: In the different G groups, none of the patients with dual-tracer uptake pattern A had grade 3 histology, but 57% of patients with grade 1 disease had FDG avidity (25% of them resulting in dual-tracer uptake pattern C). Patients with no metastasis were well differentiated, but one of them presented with dual-tracer uptake pattern C. Different uptake patterns were also observed between primary and metastatic lesions, particularly 44% of patients with dual-tracer uptake pattern A of primary with FDG avidity of metastases. Moreover, 9 (17.6%) had new lesions detected by additional 18 F-FDG PET imaging, and 3 of them (5.9%) had clinical stage changed accordingly. The Cox regression test showed that the dual-tracer uptake patterns were significantly correlated with PFS by univariate and multivariate analyses ( P = 0.026 and 0.039, respectively), whereas the grade and stage did not correlate with survival (all P >0.05). CONCLUSION: The current study has proven the uptake heterogeneity of the NET at initial diagnosis and demonstrated the staging and prognostic value of dual-tracer PET imaging. Our preliminary results have confirmed the importance of dual-tracer imaging modalities and concluded that dual-tracer PET imaging could be considered as prognostic tool for all patients with an initial diagnosis of NET.

An automated method for the assessment of the rice grain germination rate.

The germination rate of rice grain is recognized as one of the most significant indicators of seed quality assessment. Currently, grain germination rate is generally determined manually by experienced researchers, which is time-consuming and labor-intensive. In this paper, a new method is proposed for counting the number of grains and germinated grains. In the coarse segmentation process, the k-means clustering algorithm is applied to obtain rough grain-connected regions. We further refine the segmentation results obtained by the k-means algorithm using a one-dimensional Gaussian filter and a fifth-degree polynomial. Next, the optimal single grain area is determined based on the area distribution curve. Accordingly, the number of grains contained in the connected region is equal to the area of the connected region divided by the optimal single grain area. Finally, a novel algorithm is proposed for counting germinated grains. This algorithm is based on the idea that the length of the intersection between the germ and the grain is less than the circumference of the germ. The experimental results show that the mean absolute error of the proposed method for germination rate is 2.7%. And the performance of the proposed method is robust to changes in grain number, grain varieties, scale, illumination, and rotation.

Association between serum NLRP3 and malignant brain edema in patients with acute ischemic stroke.

BACKGROUND: We aimed to explore the association of serum level of the nucleotide-binding oligomerization domain-like receptor family pyrin domain-containing 3 (NLRP3) and its related inflammatory biomarkers (hypoxia inducible factor-1α, cathepsin B, caspase-1 and matrix metalloproteinase-9) with malignant brain edema (MBE) in patients with acute ischemic stroke. METHODS: We prospectively enrolled patients with acute ischemic stroke admitted < 24 h from onset of symptoms. Brain CT was performed on admission and blood samples were collected. Repeated brain CT/MRI was performed < 7 days of admission to identify the presence of MBE, defined as neurological deterioration with imaging signs of midline shift or compressed basal cisterns. Logistic regression analysis was performed to assess the association between inflammatory biomarkers and MBE, adjusted for age and National Institutes of Health Stroke Scale (NIHSS). RESULTS: 200 patients (69.3 ± 14.3 years; male 55 %) were included for analysis, of whom 26 patients developed MBE (median time from stroke onset to MBE 32.5 h). Compared with patients without MBE, those with MBE had higher level of serum concentration of NLRP3 (median time from onset to blood collection 3 h, 1.85 ng/ml vs. 1.11 ng/ml, P = 0.026). NLRP3 level was positively correlated with NIHSS on admission (Spearman ρ = 0.18, P = 0.01) and the association between NLRP3 and MBE was attenuated (OR 1.47, 95 % CI 0.88-2.46, P = 0.138) after adjusting for age and NIHSS. There was no significant difference in other biomarkers between MBE and non-MBE groups. CONCLUSIONS: There was a trend of association between a higher level of serum concentration of NLRP3 and an increased risk of MBE after ischemic stroke, possibly confounded by the severity of stroke, which is worth further validation in large cohort studies.

Characterization of odorants in contrasting ecotypes of Lake Taihu: algae-dominated versus macrophyte-dominated zones.

Globally, odorant incidents are occurring at an increasing frequency, magnitude, and duration under the dual influences of eutrophication and climate change. However, the contribution of multiple ecotypes to odorant production in the complicated and dynamic lake ecosystems remains unclear. In this study, the odorants and environmental conditions in algae-dominated zones (ADZs) and macrophyte-dominated zones (MDZs) in Lake Taihu were identified and characterized. Results showed that the ADZs were characterized by an abundance of pigments and nutrients and low DO levels, while the MDZs were featured as high TOC/TN ratios and high DO levels. Most odorants in ADZs and several in MDZs exceeded the odorant threshold content. The dominant odorants were dimethyl disulfide (DMDS) and dimethyl trisulfide (DMTS), ß-ionone and ß-cyclocitral in ADZs, which were associated with the accumulation and decomposition of algal detritus. For MDZs, the dominant odorants were 2-methylisoborneol (2-MIB) and geosmin, which were at least partially attributed to the massive addition of bait in a traditional aquaculture area. In addition, the odorant concentration in the water of ADZs was approximately 3 to 21 times higher than that in MDZs, while in the benthic sediment, the odorant concentration in ADZs was approximately 2 to 3 orders of magnitude higher than in MDZs. This study highlights the production and accumulation of nuisance odorants in the benthic sediment of ADZs, indicating a risk of diffusion from the sediment to the water column. This was supported by the correlation of odorants in the water column with that in the sediment. The results of this study will be helpful for the management of different ecotypes suffering from nuisance odorants problems.

Benthic cyanobacterial detritus mats in lacustrine sediment: Characterization and odorant producing potential.

Eutrophic freshwater lake ecosystems are receiving increasing public attention due to a global increase in large-scale harmful cyanobacterial blooms in surface waters. However, the contribution of phytodetritus accumulation in benthic sediments post-bloom remains unclear. In this study, field investigations were performed using microsensors to evaluate benthic phytodetritus mats by measuring TOC/TN ratios, pigments, biodegradable compounds and odorants as descriptive parameters. Results show that the massive amount of phytodetritus trapped by aquatic plants gradually evolved into benthic cyanobacterial detritus mats, which were characterized as anoxic, reductive and low pH. It was confirmed that the occurrence of odorants is more serious in the detritus mats due to decay and decomposition of the accumulated phytodetritus. The mean odorant content in the vegetated zones was 3-52 times higher than that in the unvegetated zones. The dominant odorants were dimethyl trisulfide (DMTS), ß-ionone and ß-cyclocitral, with mean contents of 52.38 ng·(g·dw)-1, 162.20 ng·(g·dw)-1 and 307.51 ng·(g·dw)-1, respectively, in the sediment. In addition, odorant production appears to be associated with the distribution of biodegradable compounds in the sediment. This is supported by the marked correlation observed between biodegradable compounds and odorants. Multiple regression analysis showed that biodegradable compounds can be used as indicators to predict odorant content in the sediment. It is noteworthy that the odorant trend in the water column and sediment is symmetrical, indicating a risk of diffusion from the sediment to the water column. This study helps to clarifying the contributions of benthic cyanobacterial detritus mats to odorant production in shallow eutrophic lakes. The information provided herein may also be useful for future management of aquatic ecosystems.

[Spatial Distribution and Pollution Evaluation of Carbon, Nitrogen, and Phosphorus in Sediments of Zhushan Bay at Taihu Lake].

To reveal the distribution characteristics of carbon, nitrogen and phosphorus in the sediments of Zhushan Bay at Taihu Lake, sedimentary columns were collected and sliced by 2 cm vertically from ten sampling points in three sections of Zhushan Bay. The content of total nitrogen (TN), total phosphorus (TP), and total organic carbon (TOC) were determined for each slice to reveal their horizontal and vertical distribution. The results showed that:spatially, the content of TN, TP, and TOC increased in the surface sediments of Zhushan Bay from the open lake area to the bay, and inside the bay these indexes were significantly higher than in the open lake area (P<0.01). The content of TN, TP, and TOC in the surface sediments in the bay (section A) were 1.53 mg·g-1, 1.55 mg·g-1, and 11.31 mg·g-1, respectively, while in the surface sediments near the open lake (section C) they were only 0.75 mg·g-1, 0.57 mg·g-1, and 6.70 mg·g-1, respectively. Vertically, a feature of surficial enrichment was shown, and the contents of carbon, nitrogen and phosphorus in all three sections showed a decreasing trend with increase of depth. The contents of TN, TP and TOC in the surface sediments are 2-3 times, 2-5 times, and 2-3 times those in the bottom sediments, respectively. Generally, the average TP content in the sediment of Zhushan Bay is 0.93 mg·g-1, suggesting an apparent heavy pollution, while the average TN content is 1.11 mg·g-1 as slight pollution. According to the organic nitrogen index and comprehensive pollution index, the northern part of Zhushan Bay is suffering from heavy pollution, where the organic pollution is relatively strong. The TP pollution index is between 1.03 and 3.87, indicating heavy pollution in Zhushan Bay.

[Composition and Distribution of Biodegradable Compounds in the Macrophyte Dominated Zone of Lake Taihu].

In shallow eutrophic lakes, benthic bioclastic deposits accumulate abundant organic carbon derived from macrophyte detritus. Taking the typical macrophyte-dominated Xukou Bay as the study area, field investigations were performed using sediment cores to evaluate benthic phytodetritus accumulation. Specifically, nutrient contents, TOC/TN ratios, pigmentation, and biodegradable compounds were measured as descriptive parameters. The results show that the benthic bioclastic deposit had accumulated abundant pigments, nutrients, and biodegradable compounds derived from macrophytes detritus. These were mainly localized in the top 15 cm of sediments. Nitrogen loading in the sediments was significantly higher than phosphorous loading, with a distinct spatial difference; the total nitrogen content ranged from 127.2-2092.8 mg·kg-1 and total phosphorous content ranged from 222.1-528.4 mg·kg-1. Moreover, nitrogen loading (1033.6 mg·kg-1) in the vegetated zones were higher than in the unvegetated zones (325.2 mg·kg-1). In addition, carbohydrate (3.7 mg·g-1) was the dominant component of sedimentary bioclastic material, with lipids (2.8 mg·g-1) being the second most abundant of the biodegradable compounds. The major sources of nutrients and biodegradable compounds in the sediment were massive aggregates of macrophyte detritus. The pigment, nutrient, and biodegradable compound contents in the vegetated zones were significantly higher than in unvegetated zones (P<0.01). The benthic eutrophic state showed a trend from mesotrophic to eutrophic in Xukou Bay, which should be given more attention in the future management of freshwater lake ecosystems.