In vivo binding properties of [carbonyl-11C]WAY-100635: effect of endogenous serotonin

[Carbonyl-(11)C]WAY-100635 has been reported to be a useful ligand for the investigation of 5-HT(1A) receptor imaging in vivo. However, the cellular distribution and the influence of endogenous serotonin (5-HT) on in vivo binding have not been fully examined. In this study, we investigated the effect of 5,7-dihydroxytryptamine-produced destruction of 5-HT neurons, reserpine-induced 5-HT depletion, and fenfluramine-induced 5-HT increase on [carbonyl-(11)C]WAY-100635 binding in vivo. There was no significant change in the uptake of [carbonyl-(11)C]WAY-100635 in the slice of 5-HT denervated rat brain except in the raphe nucleus, where 5-HT cell bodies exist. There was no obvious effect of enhanced 5-HT release by fenfluramine or decreased release by reserpine on [carbonyl-(11)C]WAY-100635 binding in the dissected brain region. No significant effect was observed in the time course of [carbonyl-(11)C]WAY-100635 in the hippocampus and frontal cortex measured by PET. These results indicated that the in vivo binding of [carbonyl-(11)C]WAY-100635 in the hippocampus and cerebral cortex mainly reflects postsynaptic 5-HT(1A) receptor binding, and that this binding is not sensitive to endogenous 5-HT.

Direct Z-Scheme Heterojunction of Ligand-Free FAPbBr3/α-Fe2O3 for Boosting Photocatalysis of CO2 Reduction Coupled with Water Oxidation

Up to now, the majority of the developed photocatalytic CO₂ reduction systems need to use expensive sacrificial reductants as electron source. It is still a huge challenge to drive the photocatalytic CO₂ reduction using water as an electron source. Herein, we report a facile strategy for the construction of direct Z-scheme heterojunction of LF-FAPbBr₃/α-Fe₂O₃, which is manufactured by the in situ and two-step controlled growth of ligand-free formamidinium lead bromide (LF-FAPbBr₃) nanocrystals on the surface of α-Fe₂O₃ nanorods. The matchable energy levels and direct contact between LF-FAPbBr₃ and α-Fe₂O₃ significantly accelerate the interfacial charge transfer, with a charge separation efficiency (η_separation) of 93%, much higher than that of 11% shown by the ligand-capped FAPbBr₃/α-Fe₂O₃ heterojunction. The resulting efficient separation and raised redox ability of photogenerated carriers endow the LF-FAPbBr₃/α-Fe₂O₃ heterojunction with an outstanding photocatalytic performance for CO₂ reduction (to CO and CH₄) coupled with water oxidation (to O₂), achieving a highest electron consumption rate of 175.0 μmol g^-1 h^-1 among the reported metal halide perovskite-based photocatalysts, which are 5 and 11 times higher in comparison with those of sole LF-FAPbBr₃ and ligand-capped FAPbBr₃/α-Fe₂O₃, respectively.

Dementia with Lewy bodies can be well-differentiated from Alzheimer's disease by measurement of brain acetylcholinesterase activity-a [11C]MP4A PET study

OBJECTIVE

To investigate the diagnostic performance of brain acetylcholinesterase (AChE) activity measurement using N-[(11) C]-methyl-4-piperidyl acetate (MP4A) and PET in patients with dementia with Lewy bodies (DLB) and Alzheimer's disease (AD).

METHODS

Participants were 14 DLB patients, 25 AD patients and 18 age-matched healthy controls (HC). All subjects underwent PET scans and MP4A to measure regional brain AChE activity. We performed anatomical standardization of each brain image, and k3 values, an index of AChE activity, in each voxel were estimated by nonlinear least squares analysis. Volumes of interest (VOIs) were identified on parametric k3 images in frontal, temporal, parietal and occipital cortices, and in anterior and posterior cingulate gyri (ACG and PCG). In each VOI, the differential diagnostic performance between AD and DLB of k3 values was assessed by area under the curve (AUC) of the receiver-operating characteristic. Voxel-based statistical analyses were also performed.

RESULTS

Mean cortical AChE activities in AD patients (-8.2% compared with normal mean) and DLB patients (-27.8%) were lower than HCs (p < 0.05, p < 0.001, respectively). There was a significant difference in mean cortical AChE activities between AD and DLB patients (p < 0.001). All regional brain AChE activities of defined VOIs except ACG were able to well discriminate DLB from AD, and notably performance was the most significant in PCG (AUC = 0.989, 95% CI: 0.965-1.000).

CONCLUSIONS

Brain cholinergic deficit is consistently prominent in DLB compared with AD. PET measurement of brain AChE activity may be useful for the differential diagnosis between DLB and AD.

A prodrug of NMDA/glycine site antagonist, L-703,717, with improved BBB permeability: 4-acetoxy derivative and its positron-emitter labeled analog

4-Acetoxy derivative (1) of L-703,717, a high-affinity (IC50=4.5 nM) antagonist for the glycine site of NMDA receptors, was synthesized and its brain uptake was examined using a carbon-11 labeled analog ([11C]1). Initial radioactivity in the brain after intravenous injection of [11C]1 was a 2-fold that of [11C]L-703,717 in mice. Rapid bioconversion of [11C]1 into [11C]L-703,717 was demonstrated by metabolite analyses of rat brain after [11C]1 injection. Ex vivo autoradiography of [11C]1 in rat brain showed the same cerebellar localization of radioactivity as [11C]L-703,717. These results indicate that 1 is a promising pharmacological tool as a prodrug of L-703,717 with improved BBB permeability.

Dexamethasone enhances the antitumor efficacy of Gemcitabine by glucocorticoid receptor signaling

Gemcitabine (Gem) is currently used as the first-line therapy for liver and pancreatic cancer but has limited efficacy in most cases. Dexamethasone (Dex) have been applied as a chemoprotectant and chemosensitizer in cancer chemotherapy. This study further explored the potential of combination of Gem and Dex and tested the hypothesis that glucocorticoid receptor signaling is essential for the synergistic antitumor activity. In the HepG2 and AsPC-1 xenograft models, the combination treatment showed a significantly synergistic antitumor activity. Immunohistochemistry of post-treatment tumors showed a significant decrease in proliferation and angiogenesis as compared to either of the treatments alone. Dex alone and the combination with Gem inhibited the expression of glucocorticoid receptor. The combination of Dex and Gem showed synergistic cytotoxicity in cell lines in vitro. The antiproliferative synergism is prevented by used glucocorticoid receptor (GR) small interfering RNA, demonstrating that the glucocorticoid receptor is required for the antiproliferative synergism of Gem and Dex. The inhibition of glucocorticoid receptor signaling pathway and induction of apoptosis via activation of caspases 3, 8 and 9, PARP, contributed to the synergistic effect of this combination therapy. These results demonstrate that Dex could potentiate the antitumor efficacy of Gem. The synergistic antitumor activity of the combination of Dex and Gem was through glucocorticoid receptor signaling. Taken together, a combination of Dex and Gem shows a significant synergistic antitumor activity and lesser toxicity both in vitro and in vivo and could be a combination chemotherapy for the treatment of highly expression of glucocorticoid receptor patients.

Human UGT2B7 is the major isoform responsible for the glucuronidation of clopidogrel carboxylate

Clopidogrel is predominantly hydrolyzed to clopidogrel carboxylic acid (CCA) by carboxylesterase 1, and subsequently CCA is glucuronidated to clopidogrel acyl glucuronide (CAG) by uridine diphosphate-glucuronosyltransferases (UGTs); however, the UGT isoenzymes glucuronidating CCA remain unidentified to date. In this study, the glucuronidation of CCA was screened with pooled human liver microsomes (HLMs) and 7 human recombinant UGT (rUGT) isoforms. Results indicated that rUGT2B7 exhibited the highest catalytical activity for the CCA glucuronidation as measured with a mean V_max value of 120.9 pmol/min/mg protein, 3- to 12-fold higher than that of the other rUGT isoforms tested. According to relative activity factor approach, the relative contribution of rUGT2B7 to CCA glucuronidation was estimated to be 58.6%, with the minor contributions (3%) from rUGT1A9. Moreover, the glucuronidation of CCA followed Michaelis-Menten kinetics with a mean K_m value of 372.9 μM and 296.4 μM for pooled HLMs and rUGT2B7, respectively, showing similar affinity for both. The formation of CAG was significantly inhibited by azidothymidine and gemfibrozil (well-characterized UGT2B7 substrates) in a concentration-dependent manner, or by fluconazole (a typical UGT2B7-selective inhibitor) in a time-dependent manner, for both HLMs and rUGT2B7, respectively. In addition, CCA inhibited azidothymidine glucuronidation (catalyzed almost exclusively by UGT2B7) by HLMs and rUGT2B7 in a concentration-dependent manner, indicating that CCA is a substrate of UGT2B7. These results reveal that UGT2B7 is the major enzyme catalyzing clopidogrel glucuronidation in the human liver, and that there is the potential for drug-drug interactions between clopidogrel and the other substrate drugs of UGT2B7.

DBDx-based drug combinations show highly potent therapeutic efficacy against human pancreatic cancer xenografts in athymic mice

Previous studies have shown that DBDx, a combination consisting of dipyridamole, bestatin and dexamethasone is highly effective against several cancer xenografts in athymic mice. Here the therapeutic effects of DBDx and its combination with gemcitabine or capcitabine against human pancreatic cancer xenografts and the mechanism were studied. In vivo experiments performed in athymic mice showed that the antitumor efficacy of DBDx was much stronger than that of gemcitabine or capecitabine alone. Notably, the combination of DBDx and gemcitabine or capcitabine further enhanced the efficacy. In the case of DBDx (242 mg/kg) plus gemcitabine (100 mg/kg), tumor weight decreased about 97.7%, and tumor sizes were shrinking during the treatment. In the case of DBDx (242 mg/kg) plus capecitabine (718.7 mg/kg), tumor weight decreased about 94.9%. Moreover, DBDx and its combinations obviously prolonged theoverall survival of mice compared with gemcitabine or capcitabine alone. DBDx-based drug combination therapy showed no obvious systematic toxicity. The gene expression profile analysis showed that the genes changed by DBDx were related to immune system and tumor vasculature. The result of protein array showed that the changed proteins in the serum of treated mice were related to immune and inflammation system. These results show that DBDx-based drug combinations, a new strategy which integrates the use of low-cytotoxic drugs and cytotoxic chemotherapeutics, are highly effective regimens against human pancreatic cancer in athymic mice at well tolerated doses. DBDx-based drug combination therapy might provide new options for the treatment of pancreatic cancer.

Direct Partial Transformation of 2D Antimony Oxybromide to Halide Perovskite Heterostructure for Efficient CO2 Photoreduction

The photocatalytic activity of lead-free perovskite heterostructures currently suffers from low efficiency due to the lack of active sites and the inadequate photogenerated carrier separation, the latter of which is hindered by slow charge transfer at the heterostructure interfaces. Herein, a facile strategy is reported for the construction of lead-free halide-perovskite-based heterostructure with swift interfacial charge transfer, achieved through direct partial conversion of 2D antimony oxybromide Sb4O5Br2 to generate Cs3Sb2Br9/Sb4O5Br2 heterostructure. Compared to the traditional electrostatic self-assembly method, this approach endows the Cs3Sb2Br9/Sb4O5Br2 heterostructure with a tightly interconnected interface through in situ partial conversion, significantly accelerating interfacial charge transfer and thereby enhancing the separation efficiency of photogenerated carriers. The cobalt-doped Cs3Sb2Br9/Sb4O5Br2 heterostructure demonstrates a record-high electron consumption rate of 840 µmol g-1 h-1 for photocatalytic CO2 reduction to CO coupled with H2O oxidation to O2, which is over 74- and 16-fold higher than that of individual Sb4O5Br2 and Cs3Sb2Br9, respectively. This work provides an effective strategy for promoting charge separation in photocatalysts to improve the performance of artificial photosynthesis.

[Current application and limitations of augmented reality in the stomatology]

Computer-assisted technology are gradually integrated into dental education and clinical treatment. As a cutting-edge technology in computer-aided medicine, augmented reality can not only be used as an aid to dental education by presenting three-dimensional scenes for teaching demonstration and experimental skills training, but also can superimpose virtual image information of patients onto real lesion areas for real-time feedback and intraoperative navigation. This review explores the current applications and limitations of augmented reality in dentistry to provide a reference for future research.

[Analysis on monitoring results of occupational hazards in Yangzhou city from 2014 to 2018]

Objective: To undersand the monitor of occupational hazards in the enterprises in the past 5 years, as well as the distribution of occupational disease hazards and their dynamic changes in their respective jurisdictions, for providing scientific basis for prevention and control of occupational diseases in relevant departments. Methods: Taking the method of cluster sampling, select the monitoring results of the occupational disease hazard factors commissioned by the Municipal Center for Disease Control and Prevention from 2014 to 2018 and the annual monitoring data of the network of the occupational hazard declaration system of the Safety Supervision Bureau, using chi-square test, trend Statistical analysis was performed by chi-square test or Fisher exact probability method. Results: There were 461 testing companies in the past 5 years, with a total of 15, 186 monitoring points and 43428 samples. The pass rate was 94.32% (14324/15186) . The pass rate was increasing year by year from 2014 to 2017 (P<0.05) ; The pass rate of various occupational disease hazards surveillance were greater than 90% except the rate of physical factors. In 2014, the qualified rate of physical factors was the lowest, which was 86.99% (1558/1791) ; the production rate of different production scale enterprises in 2018 was higher than that of 2014. From 2014 to 2018, the number of inspection enterprises and the number of inspection points of the joint-stock economy and state-owned economic enterprises are both high, 58 (10091 points) and 71 (1830 points) respectively; The qualified rate of state-owned economy and collective economy monitoring is high, 98.36% (1800/1830) and 100% (74/74) respectively. It had reached more than 95%; The enterprises tested mainly from the economic development zone and Guangling, respectively accounting for 34.27% (158/461) and 33.84% (156/461) of the total number of enterprises. Which followed by the Hanjiang, accounting for 23.21% of the total number of enterprises (107/461) ; The monitoring enterprises were mainly distributed in the manufacturing and power industries, which accounted for 85.25% (393/461) and 6.07% (28/461) of the total number of enterprises, respectively. Conclusion: The monitoring rate of enterprises had been increasing year by year from 2014 to 2018. Noise was the main disease prevention and controlling factor in the area.In addition, micro-enterprises, individual economy and foreign-invested economy were the key targets for occupational health.

Invasive pulmonary fungal infections in children with severe human adenovirus type 7 pneumonia: A retrospective study

BACKGROUND

There has been a rapid increase in the number of human adenovirus type 7 (HAdV-7) and invasive pulmonary fungal infections (IPFIs) co-infection.

METHODS

In this study, we included patients with confirmed HAdV-7 infection during the period from 2018 to 2019 to explore clinical characteristics of severe HAdV-7 pneumonia combined with IPFIs.

RESULTS

Among the 143 patients, 35 cases were co-infected with IPFIs. Others were assigned to the control group (n Z 108). Patients wereprone to be complicated with respiratory failure, heart failure and hemophagocytic syndromein IPFIs group. Thirty-one species of fungi were detected in the IPFIs group, among whichAspergillus was the most common species. Compared to control group, patients had lowerlevels of WBC, CD3þ T lymphocyte counts and CD19þ B lymphocyte counts in IPFIs group.

CONCLUSION

Aspergillus is the most common species in IPFIs combined with severe HAdV-7 pneumonia. For children with severe HAdV-7 pneumonia who are younger, have a long course of disease, and have been admitted to the ICU, we should predict the occurrence of IPFIs when there is multi-system dysfunction and the reduction of CD3+ T lymphocyte counts and CD19+ B lymphocyte counts in course of their disease.

[Esophageal dysmotility detection in patients with gastroesophageal reflux-related cough and its influence on the efficacy of anti-reflux therapy]

Objective: To investigate the characteristics of esophageal dysmotility in patients with an initial diagnosis of acid/non-acid gastroesophageal reflux-related cough (GERC), and its correlation with the therapeutic response to anti-reflux treatments to search for the useful indicators to screen patients with chronic cough suitable for anti-reflux therapy. Methods: A total of 173 patients with suspicious GERC who attended the Chronic Cough Specialist Clinic of Department of Pulmonary and Critical Care Medicine, Tongji Hospital, School of Medicine, Tongji University between June 2020 and December 2022 were retrospectively selected for the study. The age of the patients was (45.1±14.6) years old, including 87 males and 86 females. Their demographic characteristics, clinical manifestations, and the results of high-resolution manometry (HRM) and multichannel intraluminal impedance-pH monitoring (MII-pH) were collected. Information on the etiological identification process and final diagnosis was also recorded. The recruited cases were grouped according to therapeutic outcomes and divided into cases with a favourable response to conventional anti-reflux treatment, cases with a favourable response to intensified anti-reflux treatment, and cases with no response to anti-reflux treatment. Factors influencing the efficacy of anti-reflux treatment were investigated. Differences between groups were compared using the χ2 test, Student-Newman-Keuls test, and Kruskal-Wallis H(K) test, where applicable. Logistic regression analysis using forward stepwise regression based on maximum likelihood estimation was used to screen for influence factors. Results: The 175 patients with suspicious GERC included 45 (26.0%) patients who responded to conventional anti-reflux treatment, 54 (31.2%) who responded to intensified anti-reflux treatment and 74 (42.8%) who did not respond to anti-reflux therapies. Esophageal dysmotility was present in 52.0% of patients (90/173), but was less common in patients who responded to conventional anti-reflux treatment (χ2=8.09, P=0.018). Although the majority of reflux episodes were non-acid (136/173, 78.6%), the proportion of acid reflux (χ2=19.49, P<0.001) and acid exposure time (H=11.04, P=0.004) were significantly higher in patients who responded to conventional anti-reflux treatment. The patients with acid and non-acid GERC had comparable proportion of esophageal dysmotility (64.9% vs. 48.5%, χ2=3.11, P=0.078), with a shorter break [2.4 (0.7, 5.6) cm vs. 6.1 (1.4, 10.0) cm, Z=-2.39, P=0.017], longer upper esophageal sphincter [(4.1±0.9) cm vs. (3.7±1.3) cm, t=-2.09, P=0.038], higher percentage of normal esophageal contractions [60.0% (17.8%, 90.0%) vs. 30.0% (0, 80.0%), Z=-2.14, P=0.032], and lower percentage of large break [10.0% (0, 40.0%) vs. 50.0% (0, 100.0%), Z=-2.92, P=0.004] in the patients with non-acid GERC. The mean resting pressure of the lower esophageal sphincter was significantly lower (H=7.49, P=0.024), while the percentage of ineffective esophageal contractions was markedly higher (H=8.60, P=0.014) in the patients who responded to intensified anti-reflux treatment and in the patients who did not respond to the anti-reflux therapies. Multifactorial logistic regression analysis identified the percentage of ineffective contraction as an independent factor predicting the efficacy of conventional anti-reflux treatment, with a cut-off value of≤45% and a moderate predictive value (AUC=0.67, P=0.004). Conclusions: Esophageal dysmotility is common in GERC patients with different characteristics in acid and non-acid GERC. The percentage of ineffective esophageal contraction may be a useful indicator for selecting an anti-reflux strategy and predicting treatment outcomes.