Determination of 90Sr and 210Pb in food samples by liquid scintillation counting after sequential separation with an extraction chromatographic column.

90Sr and 210Pb are considered to be key radionuclides in internal exposure resulting from dietary intake, however, the established methods employed for their detection are time-comsuming. A method for the sequential separation of 90Sr and 210Pb using a Sr·spec resin by LSC measurement is developed, which is highly suitable for food safety monitoring as its minimal sample requirements. The sequential separation of Sr and Pb from the sample was using 0.05 mol/L HNO3 and 0.05 mol/L C6H5O7(NH4)3. The chemical recoveries of Sr and Pb measured using ICP-OES were 72-83% and 80-88%, respectively. The minimum detectable activities of 90Sr and 210Pb in the food sample were 36.2 mBq/kg and 28.6 mBq/kg, respectively, obtained from a 0.1 kg fresh sample and 300 min counting time. The method was validated using reference materials and compared with other methods. The feasibility of the developed method for other highly complex food matrices needs further investigation.

Simultaneous determination of 226Ra and 228Ra in food samples using liquid scintillation counting.

The 228Ra and 226Ra isotopes of radium are significant contaminants in food, raising public concern because of their radiotoxicity. Several methods are available for determining 228Ra and 226Ra. However, the application of these procedures is not focused on food but only on water and environmental matrices. In this study, a cost-effective method for the simultaneous determination of 226Ra and 228Ra radioactivity in food samples using liquid scintillation counting was developed. The overall efficiencies of 226Ra and 228Ra in the food samples are 69.4-78.4% and 30.1-35.8%, respectively. The minimum detectable activities of 226Ra and 228Ra are 11.3 mBq/g and 33.4 mBq/g, respectively, in our food sample, obtained using a 1.0 g ash sample and 60 min of counting time. The method was validated using IAEA-certified reference materials and compared with data obtained using gamma spectrometry in tea, kelp, and oyster samples.

Physical exercise can enhance meaning in life of college students: the chain mediating role of self-efficacy and life satisfaction.

Meaning in life refers to an individual's capacity to understand and grasp the meaning of their own existence, as well as being aware of the goals, tasks, or missions in their personal life. Previous studies have found that college students lack meaning in life, but physical exercise can enhance it. In this study, 3,196 college students completed self-report questionnaires to assess self-efficacy, life satisfaction, physical exercise, and meaning in life. The results revealed that the physical exercise not only influenced an individual's perceived meaning in life directly, but also influenced it through self-efficacy. Furthermore, it confirmed the chain mediating role of self-efficacy and life satisfaction, whereby engaging in physical exercise can ultimately impact meaning in life through self-efficacy and life satisfaction. This discovery can help educators create interventions to improve college students' physical exercise engagement and overall life satisfaction.

Levels and Distributions of 210Pb and 210Po in Selected Seafood Samples in China and Assessment of Related Dose to Population.

In this study, the activity concentrations levels of 210Pb and 210Po in the edible portions of eight seafood samples collected from the Fujian coast of China were determined. The activity concentrations ranged from 0.74 ± 0.08 to 12.6 ± 1.0 Bq/kg for 210Po and from the minimum detectable limit (MDL, 0.80 Bq/kg) to 11. 7 ± 1.1 Bq/kg for 210Pb. The 210Po activity concentration in all the fish organs ranged from 0.68 to 204 Bq/kg (w.w.), and the 210Po activity was mainly concentrated in the stomach, spleen, heart, liver, gonad, and intestine samples. The 210Pb activity concentration in all the fish organs ranged from the MDL to 15.2 Bq/kg (w.w.), and the 210Pb activity was concentrated in the head, fish scale, and gill samples. The annual effective ingestion doses ranged from 82.8 to 255 µSv/a for all age groups, and the lifetime risk of cancers were estimated. Both the effective ingestion doses and cancer risk to humans were within the acceptable ranges.

Artificial intelligence manages congenital cataract with individualized prediction and telehealth computing.

A challenge of chronic diseases that remains to be solved is how to liberate patients and medical resources from the burdens of long-term monitoring and periodic visits. Precise management based on artificial intelligence (AI) holds great promise; however, a clinical application that fully integrates prediction and telehealth computing has not been achieved, and further efforts are required to validate its real-world benefits. Taking congenital cataract as a representative, we used Bayesian and deep-learning algorithms to create CC-Guardian, an AI agent that incorporates individualized prediction and scheduling, and intelligent telehealth follow-up computing. Our agent exhibits high sensitivity and specificity in both internal and multi-resource validation. We integrate our agent with a web-based smartphone app and prototype a prediction-telehealth cloud platform to support our intelligent follow-up system. We then conduct a retrospective self-controlled test validating that our system not only accurately detects and addresses complications at earlier stages, but also reduces the socioeconomic burdens compared to conventional methods. This study represents a pioneering step in applying AI to achieve real medical benefits and demonstrates a novel strategy for the effective management of chronic diseases.

A Pilot Clinical Study of Intravitreal Injection of Artesunate for Ocular Neovascularization.

Purpose: To evaluate the efficacy and primary safety of treatment with artesunate in reducing ocular neovascularization in humans. Methods: Five patients with corneal, iris, and retinal neovascularization and no light perception were treated with intravitreal injections of artesunate 80 µg. Visual acuity, anterior segment photography, fundus fluorescein angiography, and optical coherence tomography were used to evaluate efficacy, while intraocular pressure (IOP) and lens opacity degree were employed to evaluate safety. The primary endpoint was attenuation of neovascularization as determined at 24 weeks, with the last posttreatment follow-up at 52 weeks. Results: Corneal and iris neovascularization, which were secondary to fundus ischemic diseases and retinal neovascularization in all 5 patients, were attenuated after 1 or 2 injections by the 52-week follow-up. Retinal neovascularization was also attenuated, and papilledema was alleviated. The average IOP fell from 25.5 mmHg to 17.66 mmHg. Conclusions: This pilot study determined that intravitreal artesunate injection is efficacious for reducing corneal, iris, and retinal neovascularization. These results indicate that this drug may be a novel alternative to the currently popular antivascular endothelial growth factor drugs used to suppress ocular neovascularization and improve visual function.

Intravitreal anti-VEGF agents, oral glucocorticoids, and laser photocoagulation combination therapy for macular edema secondary to retinal vein occlusion: preliminary report.

AIM: To evaluate the efficacy and safety of combined anti-vascular endothelial growth factor (VEGF) agents, oral glucocorticoid, and laser photocoagulation therapy for macular edema (ME) secondary to retinal vein occlusion (RVO). METHODS: This study included 16 eyes of 16 patients with RVO-associated ME. Patients were initially treated with oral prednisone and an intravitreal anti-VEGF agent. Two weeks later, patients underwent standard laser photocoagulation. Best-corrected visual acuity (BCVA), central retinal thickness (CRT), and retinal vessel oxygenation were examined over 12mo. RESULTS: Patients received 1.43±0.81 anti-VEGF injections. Mean baseline and 12-month logMAR BCVA were 0.96±0.51 (20/178) and 0.31±0.88 (20/40), respectively, in eyes with central retinal vein occlusion (CRVO) (P<0.00), and 1.02±0.45 (20/209) and 0.60±0.49 (20/80), respectively, in eyes with branch retinal vein occlusion (BRVO) (P<0.00). At 12mo, CRT had significantly decreased in eyes with CRVO (P<0.00) and BRVO (P<0.00). Venous oxygen saturation had significantly increased in eyes with CRVO (P<0.00) and BRVO (P<0.00). No examined parameters were significantly different between the 2 RVO groups. No serious adverse effects occurred. CONCLUSION: Anti-VEGF, glucocorticoid, and photocoagulation combination therapy improves visual outcome, prolongs therapeutic effect, and reduces the number of intravitreal injections in eyes with RVO-associated ME.

Macular Retinal Vessel Oxygen Saturation Elevation in Chinese Central Serous Chorioretinopathy.

PURPOSE: To evaluate the retinal vessel oxygen saturation in central serous chorioretinopathy (CSC) cases among the Chinese. METHODS: Relative oxygen saturation of retinal blood vessels was measured in 33 Chinese patients with single-eye CSC using the Oxymap T1 retinal oximeter. The contralateral eyes were the control. The mean saturation of the retinal arteriole (AS) and venule (VS), arteriovenous difference (AVS), and arteriole and venule diameters (AD, VD) was analyzed in the optic disc area and macular region. RESULTS: In the optic disc area, the inferotemporal quadrant (TI) AS (93.2 ± 10.2%) and inferonasal quadrant (NI) VS (61.3 ± 7.3%) were higher in the affected eyes than in the contralateral eyes (88.7 ± 7.7% and 56.9 ± 6.5%) and AVS in NI (36.7 ± 10.4%) decreased compared to the contralateral eyes (41.5 ± 11.2%). The VD in TI was expanded (19.9 ± 2.5 pixels versus 18.1 ± 3.4 pixels). Around the macular region, AS was 93.6 ± 7.6%, higher than in the contralateral eyes (89.5 ± 6.3%). No other significant changes were found. CONCLUSIONS: AS increased in the TI, and VS decreased in the NI in the eyes with CSC. In addition, AS also increased around the macular region, suggesting that these are contributors to CSC pathophysiology.

RISK OF SILICONE OIL AS VITREOUS TAMPONADE IN PARS PLANA VITRECTOMY: A Systematic Review and Meta-Analysis.

PURPOSE: The authors examined the differences between silicone oil and other vitreous tamponades or placebo in performing pars plana vitrectomy. METHODS: This review and meta-analysis was conducted in accordance with the PRISMA guidelines. Seven databases and the reference lists of the retrieved randomized controlled trial articles were searched to identify eligible studies. The primary outcomes were the rate of redetachment after endotamponade removal, the rate of reoperation, and poor visual acuity. The secondary outcomes were adverse events and quality of life related to postoperative position. RESULTS: Ten articles (12 trials) were included. There were no significant differences between silicone oil and other agents in most of the primary and second outcomes. Only the risk of hypotony was found to be significantly lower when filling with silicone oil, compared with other agents. No trial reported the quality of life related to postoperative position. CONCLUSION: Based on the available studies, the authors conclude that there is no significant difference in the risk of poor outcomes between pars plana vitrectomy with silicone oil and that with other vitreous tamponades with different surgical histories.

Small Molecular-Sized Artesunate Attenuates Ocular Neovascularization via VEGFR2, PKCα, and PDGFR Targets.

Ocular neovascularization (NV) is the primary cause of blindness in many ocular diseases. Large molecular weight anti- vascular endothelial growth factor (VEGF) protein drugs, such as Avastin and Lucentis, have saved the vision of millions. However, approximately 20-30% of patients respond poorly to anti-VEGF treatment. We found that artesunate (ART), a small molecular derivative of artemisinin, had a significant inhibitory effect on ocular NV by downregulating the expression of VEGFR2, PKCα, and PDGFR. ART significantly inhibited retinal NV in rabbits and macular edema in monkeys with greater anterior chamber penetrability and more durable efficacy than Avastin. Our pilot study showed that intravitreal injection of 80 µg ART significantly inhibited iris and corneal NV in a severe retinal detachment case. Our results suggest that ART might be a potential persistent small-molecule drug to manage ocular NV via multi-targets.

The efficacy and safety of a novel posterior scleral reinforcement device in rabbits.

PURPOSE: To evaluate the efficacy and safety of posterior scleral reinforcement (PSR) device for myopia suppression in rabbits' eyes. METHODS: PSR surgery was performed on the normal 12 8-week-old New Zealand white rabbits' right eyes. To determine efficacy of the device, ophthalmic examination would be taken at pre-operation and post-operation (1 week, 1 month, 3 months, 6 months, and 1 year), such as A-ultrasound, diopter and B-ultrasound. Evaluation of safety were based on the following indicators: intraocular pressure (IOP), slit lamp, fundus photography, fundus fluorescein angiography and pathological examination after surgery. The efficacy and safety of PSR device were evaluated by comparison (treated eyes and contralateral eyes) of pre and post-operation. RESULTS: The novel PSR device could significantly shorten axial length (preoperative axial length: 16.36 ± 0.14 mm, postoperative 1 week, 1 month, 3 months, 6 months and 1 year axial lengths: 15.03 ± 0.28 mm, 15.23 ± 0.32 mm, 15.39 ± 0.31 mm, 15.45 ± 0.22 mm and 15.45 ± 0.22 mm; P=0.00037<0.001) in the treated eyes (right eyes) after surgery. At different postoperative time points, the B-ultrasound images showed that the PSR located in appropriate position and supported the posterior sclera very well. At the same time, IOP of treated eyes kept a relatively stable level (preoperative IOP: 12.56 ± 2.01 mmHg, postoperative IOP: ranging from 11.33 ± 1.23 mmHg to 13.44 ± 2.19 mmHg, P>0.05) post-operation 1 year. During observation period, there was no significant inflammatory reaction and complications such as anterior chamber flare, empyema, endophthalmitis, vitreous hemorrhage, retina detachment and retinal choroid neovascularization by slit lamp, fundus photography and fundus fluorescein angiography. In addition, there were no pathologic changes be found by comparison treated eyes group and contralateral group eyes based on pathological examinations. CONCLUSIONS: In vivo study, effectively and safely, the novel PSR device can inhibit rabbits' axial length elongation during postoperative 1 year. This study demonstrates that this novel PSR could be a potential treatment approach for myopia.

Study of retinal vessel oxygen saturation in ischemic and non-ischemic branch retinal vein occlusion.

AIM: To explore how oxygen saturation in retinal blood vessels is altered in ischemic and non-ischemic branch retinal vein occlusion (BRVO). METHODS: Fifty BRVO eyes were divided into ischemic (n=26) and non-ischemic (n=24) groups, based on fundus fluorescein angiography. Healthy individuals (n=52 and n=48, respectively) were also recruited as controls for the two groups. The mean oxygen saturations of the occluded vessels and central vessels were measured by oximetry in the BRVO and control groups. RESULTS: In the ischemic BRVO group, the occluded arterioles oxygen saturation (SaO2-A, 106.0%±14.3%), instead of the occluded venule oxygen saturation (SaO2-V, 60.8%±9.4%), showed increases when compared with those in the same quadrant vessels (SaO2-A, 86.1%±16.5%) in the contralateral eyes (P<0.05). The oxygen saturations of the central vessels showed similar trends with those of the occluded vessels. In the non-ischemic BRVO group, the occluded and central SaO2-V and SaO2-A showed no significant changes. In both the ischemic and non-ischemic BRVOs, the central SaO2-A was significantly increased when compared to healthy individuals. CONCLUSION: Obvious changes in the occluded and central SaO2-A were found in the ischemic BRVO group, indicating that disorders of oxygen metabolism in the arterioles may participate in the pathogenesis of ischemic BRVO.

Retinal vessel oxygen saturation and vessel diameter in high myopia.

PURPOSE: To investigate changes in retinal vessel oxygen saturation and diameter in high myopia. METHODS: Relative oxygen saturation was measured in the retinal blood vessels of 54 participants with high myopia and compared to a control group of 54 individuals with emmetropia with the Oxymap T1 retinal oximeter. The participants with high myopia were further divided into two groups according to the grade of myopic retinopathy: Group A (grade < M2 ) and Group B (grade ≥ M2 ). One-way anova was used to analyse the mean saturation and diameter of retinal arterioles and venules and the mean difference in arterio-venous saturation among the four groups. Further analysis of multiple comparisons was performed with the Bonferroni test. Linear regression was used to analyse the correlation of ocular perfusion pressure or best corrected visual acuity with other variables. RESULTS: For all of the high myopia patients, retinal arteriole saturation (92.3 ± 5.6%) and the difference in arterio-venous saturation (30.8 ± 5.0%) were significantly lower than in normal individuals (96.0 ± 5.8%, 35.4 ± 6.2%; p = 0.006, p < 0.001, respectively). In Group A, only the difference in arterio-venous saturation (31.0 ± 4.7%) was significantly lower than in the control group (p = 0.011). In Group B, retinal arteriole saturation (92.2 ± 5.3%) and the difference in arterio-venous saturation (30.7 ± 5.3%) were also lower than the control group (p = 0.02, p = 0.001, respectively). Both retinal arteriole diameter and retinal venule diameter were narrower than in participants with high myopia than the control group (p < 0.001). No statistically significant correlations were found between ocular perfusion pressure or best corrected visual acuity with any other variables. CONCLUSIONS: The study demonstrated decreased retinal arteriole saturation and decreased difference in arterio-venous saturation as well as narrowing retinal vessel diameter in highly myopic eyes. Further studies are needed to determine if such changes play a role in the development of high myopia and its complications or occur as a consequence of tissue remodelling during axial elongation.

Mussel-inspired polydopamine coated mesoporous silica nanoparticles as pH-sensitive nanocarriers for controlled release.

A novel pH-sensitive controlled release system is proposed by using mussel-inspired polydopamine (PDA) coated mesoporous silica nanoparticles (MSNs) as nanocarriers. MSNs with a large pore diameter are synthesized by using 1,3,5-trimethylbenzene as a pore-expanding agent and are modified with a PDA coating by virtue of oxidative self-polymerization of dopamine in neutral pH. PDA coated MSNs are characterized by FTIR, TEM, N2 adsorption and XPS techniques. The PDA coating can work as pH-sensitive gatekeepers to control the release of drug molecules from MSNs in response to the pH-stimulus. Doxorubicin (DOX, an anticancer drug) can be released in the acid media and blocked in the neutral media.

A pH-responsive controlled release system using layered double hydroxide (LDH)-capped mesoporous silica nanoparticles.

A pH-responsive controlled release system is proposed using acid-decomposable layered double hydroxides (LDHs) as inorganic nanovalves by virtue of the electrostatic adsorption of LDH nanosheets on the surface of mesoporous silica nanoparticles (MSNs). Guest molecules (Ru(bpy)3Cl2 in this case) are loaded and encapsulated in a neutral environment. The dissolution of the LDH coatings in an acidic environment triggers the release of the guest molecules from the MSNs.

A G-quadruplex based label-free fluorescent biosensor for lead ion.

Many Pb(2+) biosensors based on Pb(2+)-specific RNA-cleaving DNAzyme have been developed in the past years. However, many of them have limited practical use because of high cost (e.g., enzymes), complicated processing and the use of unstable molecules (e.g., RNA). In this study, a novel label-free fluorescent biosensor for Pb(2+) was proposed based on Pb(2+)-induced allosteric G-quadruplex (PS2.M). In the presence of K(+), N-methyl mesoporphyrin IX (NMM) could bind to K(+)-stabilized G-quadruplexes, giving rise to high fluorescence. On addition of Pb(2+), Pb(2+) competitively binded to K(+)-stabilized G-quadruplexes to form more compact DNA folds. The Pb(2+)-stabilized G-quadruplexes did not bind to NMM, which resulted in fluorescence decrease. This allowed us to utilize PS2.M for quantitative analysis of Pb(2+) using the NMM-G-quadruplex system by convenient "mix-and-detect" protocol. The fluorescence emission ratio (F(0)/F) showed a good linear response toward Pb(2+) over the range from 5.0 nM to 1.0 µM with a limit of detection of 1.0 nM. This proposed biosensor was simple and cost efficiency in design and in operation with high sensitivity and selectivity. We validated the practicality of this biosensor for the determination of Pb(2+) in lake water samples.

A sensitive and selective DNAzyme-based flow cytometric method for detecting Pb2+ ions.

A sensitive and selective Pb(2+) sensor based on GR-5 DNAzyme has been developed by a flow cytometric method.

CYP4F2 rs2108622: a minor significant genetic factor of warfarin dose in Han Chinese patients with mechanical heart valve replacement.

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT * Genetic polymorphisms of VKORC1 and CYP2C9 are known to influence warfarin dosage. * Recent studies among Caucasians showed that polymorphisms of CYP4F2 also play a role in warfarin pharmacogenetics. * The contribution of CYP4F2 variants to the variability inwarfarin dose requirement in Chinese subjects remains to be investigated. WHAT THIS STUDY ADDS * This research was to study the effect of CYP4F2 variants on warfarin requirements in the Han Chinese population. * This study developed a multiple regression model including CYP2C9, VKORC1 3673G>A, CYP4F2 genotypes and age, weight, combination use of amiodarone which could explain 56.1% of the individual variability in warfarin dose CYP4F2 could explain 4% of the variance in warfarin dose. * We found that one novel genotypic polymorphism 5417G>T for Asp36Tyr, which was identified as an important marker of warfarin resistance, was absent in the Han Chinese population in our study. AIMS The objective of this study was to assess the effect of the CYP4F2 on the daily stable warfarin dose requirement in Han Chinese patients with mechanical heart valve replacement (MHVR). METHODS From March 2007 to November 2008, 222 Han Chinese MHVR patients were recruited in our study. VKORC1 3673G>A, 5417G>T, CYP2C9*3 and CYP4F2 rs2108622 were genotyped by using the polymerase chain reaction restriction fragment length polymorphism method (PCR-RFLP). Polymorphisms of VKORC1 9041G>A were detected by direct sequencing. Multiple linear regression analysis was used to investigate the contribution of CYP4F2. RESULTS The CYP4F2 rs2108622 CT/TT group took a significantly higher stable warfarin dose (3.2 mg day(-1)) than the CC group (2.9 mg day(-1), 95% CI 0.2, 1.0, P= 0.033). The multiple linear regression model included VKORC1 3673G>A, CYP2C9, CYP4F2 genotypes and clinical characteristics. The model could explain 56.1% of the variance in stable warfarin dose in Han Chinese patients with MHVR. CYP4F2 contributed about 4% to the variance in the warfarin dose. There was no variation in the SNPs of VKORC1 5417G>T. CONCLUSION CYP4F2 is a minor significant factor of individual variability in the stable warfarin dose in Han Chinese patients with MHVR. The effect of CYP2C9 and VKORC1 genotypes on variability in the stable warfarin dose had also been confirmed.