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Background and purpose: Traditional preparation of subcutaneous transplanted tumor of prostate cancer relies on cell suspension injection. However, there are great limitations. The purpose of this study was to explore the feasibility of developing a new animal model of subcutaneous transplanted prostate cancer with cell sheet technology. Methods: Human prostate cancer DU145 cells were inoculated into a 35 mm temperature sensitive cell culture dish, and the prostate cancer cell sheet was prepared by continuous culture and identified by H-E staining and immunohistochemistry. According to the research purpose, cell suspension group and cell membrane group were set up. DU145 cell suspension was subcutaneously injected into nude mice in cell suspension group, and DU145 cell sheet was subcutaneously injected into BALB/c nude mice in cell sheet group. The BALB/c nude mice were sacrificed 4 weeks after transplantation, and the grafted tumors in both groups were dissected for further histological analysis, including collagen fiber content, local infiltration and angiogenesis. Meanwhile, the common organs of prostate cancer metastasis, such as bone, lung and liver, were dissected to evaluate the systemic metastasis in both groups. Results: DU145 prostate cancer cell sheet could be prepared at 1 week after continuous culture. Histological staining revealed a membrane structure with an average thickness of (32.6±7.5) μm. The DU145 cell sheet was rich in collagen fibrin with high vimentin expression and low E-cadherin expression. H-E staining showed that the tumor structure was dense with obvious infiltration of surrounding muscles in the cell sheet group, while the tumor had more vacuoles and a clear boundary with surrounding tissues in the cell suspension group 4 weeks after subcutaneous transplantation. Moreover, the transplanted tumor volume was significantly higher in the cell sheet group than in the cell suspension group, and the measured tumor volume in the two groups were (0.967±0.129) and (0.437±0.054) cm3 (t = 3.774, P = 0.019 5), respectively. Masson staining showed that the content of blue collagen fiber was significantly higher in the cell sheet group than in the cell suspension group, and the optical densities (D) value of the two groups were 0.023 0±0.001 1 and 0.014 0±0.000 7 (t = 7.022, P = 0.000 1), respectively. Immunohistochemical staining of CD31 showed that the microvascular density per ×200 field in the cell sheet group and the cell suspension group were 53.20±3.56 and 32.40±4.98 (t = 3.392, P = 0.009 5), respectively. Gross anatomy and H-E staining showed no obvious systemic metastasis in the two groups 4 weeks after subcutaneous transplantation. Conclusion: It is feasible and advantageous to develop the animal model of subcutaneous transplanted prostate cancer using cell sheet technology. Compared with traditional cell suspension injection method, the tumor volum was larger, the infiltration degree was deeper with surrounding tissues, the density of new microvessels was higher, and the collagen content was richer, which is more helpful to reveal the real biological characteristics of prostate cancer. It is expected to be applied in the research of molecular genetics of prostate cancer, drug resistance mechanism and drug discovery.

It is unknown how antibiotics would behave after entering the hyporheic zone (HZ), which is an area where groundwater and surface water alternate continuously. In this study, the hydrolysis process in the HZ was investigated based on the intermediates identified by HPLC-Q-TOF-MS and FTIR, and the active sites of sulfamethoxazole (SMX) were predicted by density functional theory (DFT). The results showed that the hydrolysis rate of SMX during surface water recharged groundwater reached 38.94%, and the contribution rate of hydroxyl radicals reached 48.35%. In neutral and alkaline environments, SMX hydrolysed more quickly. This is due to the fact that ·OH, as the main precursor of OH-, is much higher in quantity under alkaline conditions. Inorganic anions such as NO3-, HCO3- and ${\rm CO}_3^{2-}$ CO 3 2 − may inhibit the hydrolysis of SMX by eliminating the reactive oxygen species generated in the HZ. In the process of groundwater recharging to surface water, the concentration of dissolved oxygen (DO) and the rate of SMX hydrolysis gradually reduced. Nitrification, hydroxylation and polymerisation are the main hydrolysis pathways of SMX. The hydrolysis products of SMX in the HZ are more plentiful and have a higher hydrolysis rate compared to the single oxygen environment. The study on the hydrolysis mechanism of SMX in this paper will provide a theoretical basis for the treatment of antibiotic pollution. The degradation pathways and influencing factors of sulfamethoxazole in the hyporheic zone. [ABSTRACT FROM AUTHOR]

Background and purpose: 18 F-prostate-specific membrane antigen (PSMA)-1007 positron emission tomography and computed tomography (PET/CT) is an advanced molecular imaging evaluation method for prostate cancer (PCa). This study aimed to explore the early detection rate of recurrence and metastasis of patients with biochemical recurrence (BCR) after radical prostatectomy (RP) by 18 F-PSMA-1007 PET/CT and its influence on clinical treatment decisions. Methods: From December 2018 to December 2020, the data of 51 PCa patients with BCR after RP by 18 F-PSMA-1007 PET/CT were summarized and analyzed. Radioactive uptake of tumors was calculated semi-quantitatively by region of interest method and expressed by the maximum standardized uptake value (SUV max ). We assessed the detection rate of clinical recurrence and metastasis in BCR patients [local recurrence (prostatic bed), lymph node metastasis (pelvic, retroperitoneal and diaphragmatic), bone metastasis and visceral metastasis (such as lung)], and the difference in detection rate between prostate-specific antigen (PSA) groups and Gleason evaluation group was further compared respectively. Results: The median age of 51 patients was 66 years (52-80 years), and the median PSA was 35 ng/mL (6-224 ng/mL) at the time of initial diagnosis. All of them were prostatic acinar adenocarcinoma, including 1 case with intraductal carcinoma, 1 case with ductal adenocarcinoma, 1 case with mucinous adenocarcinoma, 1 case with signet ring-like component and 1 case with neuroendocrine differentiation. We found Gleason score ≤7 in 22 cases (43.14%) and Gleason score ≥ 8 in 29 cases (56.86%). The median time of BCR was 15 months (5-62 months), and the median PSA was 0.58 ng/mL (0.20- 110.00 ng/mL), including 21 (41.18%) cases with 0.20 ng/mL≤PSA ＜ 0.50 ng/mL, 12 (23.53%) cases with 0.50 ng/mL≤PSA ＜ 1.00 ng/mL, 4 (7.84%) cases with 1.00 ng/mL≤PSA ＜ 2.00 ng/mL and 14 (27.45%) cases with PSA≥2.00 ng/mL. There were 7 cases (13.73%) with no local recurrence or metastasis, and 44 cases (86.27%) with local recurrence or metastasis, including 9 cases (20.45%) with recurrence in the operative area of prostate, 28 cases (63.64%) had lymph node metastasis at different sites, 31 cases (70.45%) had bone metastasis, and 2 cases (4.55%) had visceral metastasis. In addition, there were 2 cases of subcutaneous nodule metastasis and 1 case of penile root metastasis. The median SUV max was 17.9 (1.4-110.9) for all recurrence or metastasis, 14.0 (3.2-110.9) for local recurrence, 10.2 (2.0-90.1) for lymph node metastasis, and 5.4 (1.4-109.6) for bone metastasis. The detection rates of recurrence or metastasis were 71.43% (15/21), 100.00% (12/12), 75.00% (3/4) and 100.00% (14/14), respectively, in the groups with 0.20 ng/mL≤PSA ＜ 0.50 ng/mL (21 cases), 0.50 ng/mL≤PSA ＜ 1.00 ng/mL (12 cases), 1.00 ng/mL≤PSA ＜ 2.00 ng/mL (4 cases) and PSA≥2.00 ng/mL (14 cases), and there was no statistically significant difference in the detection rate between groups with different PSA levels (P＞0.05). The recurrence or metastasis detection rates of original Gleason score ≤7 group (22 cases) and Gleason score ≥8 group (29 cases) were 68.18% (15/22) and 100.00% (29/29), respectively, and there were statistically significant differences in the detection rate between groups with different Gleason scores (P ＜ 0.05). In clinical treatment, 4 cases (7.84%) were treated by observation, 18 cases (35.29%) by endocrinotherapy alone, 2 cases (3.92%) by salvage radiotherapy (SRT) alone, 24 cases (47.06%) by endocrinotherapy combined with SRT, 1 case (1.96%) by endocrinotherapy combined with docetaxel systemic chemotherapy, and 2 cases (3.92%) by salvage pelvic lymphadenectomy. Conclusion: 18 F-PSMA-1007 PET/CT has a good value and efficacy in early diagnosis of clinical recurrence or metastasis of BCR patients after RP, which is conducive to accurate evaluation and optimal treatment plan for such patients, and significantly affects clinical treatment decisions.

Exploring the community characteristics of petroleum degrading bacteria and revealing the types of petroleum metabolites produced by degrading bacteria play an important role in solving the problem of oil pollution. In this study, the bacterial suspension was extracted from the sludge of the sewage treatment plant, and the efficient dominant bacteria were enriched and cultured by microbial screening. The optimal environmental conditions and kinetic behavior of microbial degradation of petroleum hydrocarbons in groundwater were discussed, and the metabolites of microbial degradation of petroleum hydrocarbons were analyzed. The results showed that the optimum degradation conditions of the strain were as follows: bacterial suspension inoculum: 2%, pH: 7, temperature: 30°C, initial concentration of contaminated water sample: 500 mg/L. Under these conditions, the microbial petroleum hydrocarbon degradation efficiency was 84.7% and followed the first‐order kinetics; qualitative and quantitative statistical analysis of the metabolites of the microbial degradation of petroleum hydrocarbons by gas chromatography‐time‐of‐flight mass spectrometry was performed. A total of 10 significantly upregulated products and 12 significantly downregulated products were screened, which were significantly different from the metabolites of the control group. Further microbial community analysis showed that Pseudomonas was dominant in the bacterial suspension, more than 99.5%, which was significantly different from the sludge sample, providing data support for the degradation of petroleum hydrocarbons by Pseudomonas. This study has provided a scientific basis for in situ remediation of petroleum pollution in groundwater. [ABSTRACT FROM AUTHOR]

All-inorganic halide perovskite quantum dots (IPQDs) have attracted considerable attention as an emerging fluorescent material owing to their excellent optical properties. However, due to the instability of IPQDs in polar solution, IPQDs have not been used in imprinting and detection in the aqueous phase. Herein, a sensitive, selective fluorescent sensor is reported, which combines luminescent CsPbBr3 quantum dots (QDs) and molecularly imprinted polymers (MIPs) for trace tetracycline (TC) detection in aqueous environments. IPQDs@MIPs were constructed by encapsulating water-soluble CsPbBr3 QDs in pre-prepared MIPs to avoid fluorescence quenching during conventional imprinted polymerization and elution, and the porous silicon matrix protected the QDs. IPQDs@MIPs solution emitted bright green fluorescence under UV lamp irradiation, confirming that IPQDs were stable in the aqueous phase and showed excellent selectivity for TC detection. Under optimal conditions, the fluorescence intensity of the IPQDs@MIPs had a good linear correlation with TC in the concentration range of 0.2–5.0 μM, and the detection limit was 28 nM. Furthermore, the imprinting factor of the IPQDs@MIPs was 4.87, and the mechanism of fluorescence quenching was mainly the electron transfer between TC and IPQDs@MIPs. The fluorescent sensor achieved satisfactory results in the standard addition recovery experiment of an actual water sample. This work paves the way for the further development of IPQDs in the field of analytical chemistry in a practical detection environment. [ABSTRACT FROM AUTHOR]

Background and purpose: 18F-prostate-specific membrane antigen (PSMA)-1007 positron emission tomography and computed tomography (PET/CT) is an advanced molecular imaging evaluation method for prostate cancer (PCa). This study aimed to explore the early detection rate of recurrence and metastasis of patients with biochemical recurrence (BCR) after radical prostatectomy (RP) by 18F-PSMA-1007 PET/CT and its influence on clinical treatment decisions. Methods: From December 2018 to December 2020, the data of 51 PCa patients with BCR after RP by 18F-PSMA-1007 PET/CT were summarized and analyzed. Radioactive uptake of tumors was calculated semi-quantitatively by region of interest method and expressed by the maximum standardized uptake value (SUVmax). We assessed the detection rate of clinical recurrence and metastasis in BCR patients [local recurrence (prostatic bed), lymph node metastasis (pelvic, retroperitoneal and diaphragmatic), bone metastasis and visceral metastasis (such as lung)], and the difference in detection rate between prostate-specific antigen (PSA) groups and Gleason evaluation group was further compared respectively. Results: The median age of 51 patients was 66 years (52-80 years), and the median PSA was 35 ng/mL (6-224 ng/mL) at the time of initial diagnosis. All of them were prostatic acinar adenocarcinoma, including 1 case with intraductal carcinoma, 1 case with ductal adenocarcinoma, 1 case with mucinous adenocarcinoma, 1 case with signet ring-like component and 1 case with neuroendocrine differentiation. We found Gleason score ≤7 in 22 cases (43.14%) and Gleason score ≥ 8 in 29 cases (56.86%). The median time of BCR was 15 months (5-62 months), and the median PSA was 0.58 ng/mL (0.20- 110.00 ng/mL), including 21 (41.18%) cases with 0.20 ng/mL≤PSA<0.50 ng/mL, 12 (23.53%) cases with 0.50 ng/mL≤PSA< 1.00 ng/mL, 4 (7.84%) cases with 1.00 ng/mL≤PSA<2.00 ng/mL and 14 (27.45%) cases with PSA≥2.00 ng/mL. There were 7 cases (13.73%) with no local recurrence or metastasis, and 44 cases (86.27%) with local recurrence or metastasis, including 9 cases (20.45%) with recurrence in the operative area of prostate, 28 cases (63.64%) had lymph node metastasis at different sites, 31 cases (70.45%) had bone metastasis, and 2 cases (4.55%) had visceral metastasis. In addition, there were 2 cases of subcutaneous nodule metastasis and 1 case of penile root metastasis. The median SUVmax was 17.9 (1.4-110.9) for all recurrence or metastasis, 14.0 (3.2-110.9) for local recurrence, 10.2 (2.0-90.1) for lymph node metastasis, and 5.4 (1.4-109.6) for bone metastasis. The detection rates of recurrence or metastasis were 71.43% (15/21), 100.00% (12/12), 75.00% (3/4) and 100.00% (14/14), respectively, in the groups with 0.20 ng/mL≤PSA<0.50 ng/mL (21 cases), 0.50 ng/mL≤PSA<1.00 ng/mL (12 cases), 1.00 ng/mL≤PSA<2.00 ng/mL (4 cases) and PSA≥2.00 ng/mL (14 cases), and there was no statistically significant difference in the detection rate between groups with different PSA levels (P>0.05). The recurrence or metastasis detection rates of original Gleason score ≤7 group (22 cases) and Gleason score ≥8 group (29 cases) were 68.18% (15/22) and 100.00% (29/29), respectively, and there were statistically significant differences in the detection rate between groups with different Gleason scores (P<0.05). In clinical treatment, 4 cases (7.84%) were treated by observation, 18 cases (35.29%) by endocrinotherapy alone, 2 cases (3.92%) by salvage radiotherapy (SRT) alone, 24 cases (47.06%) by endocrinotherapy combined with SRT, 1 case (1.96%) by endocrinotherapy combined with docetaxel systemic chemotherapy, and 2 cases (3.92%) by salvage pelvic lymphadenectomy. Conclusion: 18F-PSMA-1007 PET/CT has a good value and efficacy in early diagnosis of clinical recurrence or metastasis of BCR patients after RP, which is conducive to accurate evaluation and optimal treatment plan for such patients, and significantly affects clinical treatment decisions. [ABSTRACT FROM AUTHOR]