Ultrasensitive determination of selenium in water and food samples by ICP-MS: UiO-66-NH2 for preconcentration and direct slurry hydride generation.

BACKGROUND: Selenium is an indispensable microelement for humans and food is the main source of selenium intake. As one of the best techniques for the determination of selenium, inductive coupling plasma-mass spectrometry (ICP-MS) features some unique advantages, such as wide linear range and high sensitivity. Nevertheless, it still remains a challenge to achieve the accurate and high sensitivity determination of ultra-trace selenium in food samples by ICP-MS owning to the high first ionization energy of selenium and interferences from sample matrices as well as isobaric interferences. RESULTS: In this work, UiO-66-NH2 (metal organic framework, MOF) was fast synthesized by microwave method and employed for the preconcentration of ultra-trace selenium with an adsorption efficiency of nearly 100%. The selenium-adsorbed MOF was collected by filtration, and then simply converted to slurry for in situ hydride generation (HG) for sensitive detection of selenium by ICP-MS. Various factors affecting the adsorption of selenium by the MOF (including pH, adsorption time, and amount of MOF) together with main parameters of hydride generation (including concentrations of HCl and NaBH4) were carefully evaluated. Experimental results show that effective matrix separation can greatly reduce interference, with an excellent detection limit of 1 ng/L. The practicability and accuracy of this method were successfully confirmed by the determination of trace selenium in several food samples. SIGNIFICANCE: UiO-66-NH2 (MOF) was used as an effective adsorbent for the preconcentration of selenium prior to direct slurry sampling HG-ICP-MS determination. Direct slurry sampling avoided additional elution procedures and was conducive to eliminating matrix and isobaric interferences. High sensitivity and anti-interference determination were achieved for determination of ultra-trace Se in complex food samples.

Factors Associated With Guideline-Concordant Pharmacological Treatment for Neuropathic Pain Among Breast Cancer Survivors.

PURPOSE: To identify factors associated with receiving guideline-concordant treatment among breast cancer survivors with neuropathic pain. MATERIALS AND METHODS: A retrospective case-control study was conducted using the SEER-Medicare linked database. We included female breast cancer survivors diagnosed with non-metastatic breast cancer (stages 0-III) between 2007 and 2015 who developed treatment-related neuropathic pain during their survivorship period. Guideline-concordant treatment was defined based on NCCN guidelines. Factors associated with receiving guideline-concordant treatment were assessed using multivariable logistic regression and backward selection was used to identify potential associated factors. RESULTS: Around 16.7% of breast cancer survivors in the study developed a neuropathic pain condition. The mean time to develop neuropathic pain was 1.4 years after beginning adjuvant treatment. On average, patients who developed neuropathic pain and received guideline-concordant treatment did so at 2.4 months after their neuropathic pain diagnosis. We found that survivors that are black and of other races were less likely to receive guideline-concordant treatment for breast cancer treatment-related neuropathic pain. Whereas survivors with diabetes, mental health disorders, hemiplegia, prior continuous opioid use, benzodiazepine use, nonbenzodiazepine CNS depressant use, or antipsychotic medication use were less likely to receive guideline-concordant treatment. CONCLUSION: This study suggests that minority races, prior medication use, and comorbid conditions are associated with guideline-concordant treatment among breast cancer survivors with neuropathic pain. These findings warrant attention towards minority races to prescribe them guideline-concordant treatment as well as caution when prescribing concurrent pain medications to survivors with comorbidities and prior medication use.

Activity of Ligustrum robustum (Roxb.) Blume extract against the biofilm formation and exopolysaccharide synthesis of Streptococcus mutans.

Ligustrum robustum (Roxb.) Blume is utilized as a traditional Chinese herbal tea with various health benefits and protective effects. Streptococcus mutans is an important cariogenic oral bacteria species. The present study aimed to assess the influence of Ligustrum robustum extract (LRE) on the biofilm formation of S. mutans and the mechanism of its action, as well as to identify its chemical components. For chemical identification, HPLC-MS and nuclear magnetic resonance were applied and four identified phytochemicals were reported (Ligurobustoside B, Ligurobustoside N, Ligurobustoside J, and Ligurobustoside C). The dose-dependent (0.5 to 2.0 µg/µL) antimicrobial toxicity of LRE against S. mutans biofilm formation and exopolysaccharide (EPS) synthesis was evaluated by confocal laser scanning microscopy (CLSM), Crystal violet stain, and CFU counting. The microstructure of S. mutans biofilm treated with LRE was investigated both on glass coverslips and ex vivo bovine dental enamel by scanning electron microscopy (SEM). Moreover, LRE downregulated the expression of S. mutans glucosyltransferase-encoding genes gtfB, gtfC, and gtfD, and the quorum sensing (QS) factors comD and comE, suggesting its toxic mechanism. In addition, the result of CCK-8 test on human oral cells revealed an acceptable biocompatibility of LRE. These findings indicated the possible application of this daily consumed herbal tea for caries prevention.

Utilization of the extract of Cedrus deodara (Roxb. ex D.Don) G. Don against the biofilm formation and the expression of virulence genes of cariogenic bacterium Streptococcus mutans.

ETHNOPHARMACOLOGICAL RELEVANCE: Cedrus deodara (Roxb. ex D.Don) G. Don is applied as anti-inflammatory and anti-infection agents in folklore medicine. AIM OF THE STUDY: The present study aimed to assess the antimicrobial activity of Cedrus deodara (Roxb. ex D.Don) G. Don extract (CDE) against Streptococcus mutans biofilm formation and its biocompatibility, as well as to identify its chemical components. MATERIALS AND METHODS: Confocal laser scanning microscopy (CLSM), crystal violet staining, and CFU counting assay were applied to investigate the effect of CDE on S. mutans biofilm formation and extracellular polysaccharides (EPS) synthesis. The microstructure of S. mutans biofilms formed on glass coverslips and bovine enamel treated with CDE was observed by scanning electron microscopy (SEM). qRT-PCR was used to measure the expression of virulence genes gtfB, gtfC, and gtfD, and zymogram assay was performed to investigate the enzymatic activity of Gtfs. Moreover, HPLC-MS and NMR were applied to identify its chemical components. CCK-8 assay was also performed on human oral cells to evaluate its biocompatibility. RESULTS: Under the treatment of CDE, S. mutans formed less biofilm on both coverslips and enamel surfaces and synthesized less EPS. Moreover, CDE downregulated the expression of gtf genes and inhibited the enzymatic activity of Gtfs. According to HPLC-MS and NMR results, molecular structures of six main compounds in CDE were identified. CDE also has a good biocompatibility. CONCLUSIONS: CDE exhibits inhibitory activity against S. mutans and a good biocompatibility. It has the potential to be developed as anti-caries agents for clinical use.

Is prophylactic cranial irradiation necessary in individuals suffering from surgically resected pT1-2N0M0 small cell lung cancer?

Adjuvant chemotherapeutics and prophylactic cranial irradiation (PCI) are both recommended in the National Comprehensive Cancer Network (NCCN) guidelines for treating individuals suffering from surgically resected pT1-2N0M0 small cell lung cancer (SCLC). Whether adjuvant chemotherapy combined with PCI is superior to adjuvant chemotherapy alone in these patients is largely unknown. PCI may therefore be with uncertain effects in surgically resected pT1-2N0M0 SCLC.

Enriching Mn-Doped ZnSe Quantum Dots onto Mesoporous Silica Nanoparticles for Enhanced Fluorescence/Magnetic Resonance Imaging Dual-Modal Bio-Imaging.

Multimodal imaging is more suitable for disease diagnosis because of its ability to provide more complementary and accurate information over single-mode imaging. Mn-doped quantum dots (QDs), especially Mn-doped ZnS (ZnSe) QDs, possess unique fluorescent and magnetic properties and are thus attractive for fluorescence/magnetic resonance imaging (MRI) dual-mode imaging. However, the optimal dopant (Mn2+) concentration for maximizing the fluorescence of QDs is relatively low for the MRI imaging. Herein, based on the large Stokes shift of Mn-doped ZnSe QDs, an enrichment strategy with mesoporous silica (MSN) loading was explored for constructing a highly luminescent/paramagnetism Mn-doped ZnSe QDs assembly (MSN@QDs) for improved MRI/optical dual-model imaging. After assembly, the loading density of QDs in MSNs was estimated to be 152 ± 12. Upon loading, the fluorescence of the MSN@QDs assembly was enriched along with QDs (enrichment factor of ∼143). Because of the large Stokes shift (∼200 nm), no appreciable concentration quenching was observed. Meanwhile, the T1 MR contrast was also increased both in vitro and in vivo through improved local Mn2+ concentration, realizing MRI signal enrichment. In fluorescence imaging investigations, MSN@QDs showed better performance over both single QDs and equivalent numbers of MSN-free single QD. Therefore, this enrichment strategy allowed simultaneous signal enhancement of the two imaging modes of Mn-doped ZnSe QDs.

Banxia Xiexin Decoction Is Effective to Prevent and Control Irinotecan-Induced Delayed Diarrhea in Recurrent Small Cell Lung Cancer.

BACKGROUND: Irinotecan (CPT-11) can be used as a first-line therapeutic drug against extensive-stage small cell lung cancer (SCLC); it can also be used in second-line treatment for SCLC. CPT-11-induced delayed diarrhea restricts its clinical application. This study aimed to confirm whether Banxia Xiexin decoction was effective in preventing and controlling CPT-11-induced delayed diarrhea. METHODS: A total of 27 patients with recurrent SCLC undergoing chemotherapy regimens including CPT-11 were enrolled for the study. UGT1A1*28, UGTlAl*6, ABCB1*2, and SLCO1B1*15 gene polymorphisms were detected. If delayed diarrhea occurred in the first cycle of chemotherapy, Banxia Xiexin decoction was orally administered for 5 consecutive days starting 1 day before the second cycle of chemotherapy to prevent and control the delayed diarrhea. The objective response, overall survival, and toxicity were recorded. RESULTS: Complete response, partial response, and stable disease were observed in none, 6, and 10 patients, respectively. Delayed diarrhea occurred in 6 patients, and 4 of 5 patients were relieved or controlled using Banxia Xiexin decoction. The median overall survival was 6 months. CONCLUSION: Banxia Xiexin decoction appeared to prevent and control delayed diarrhea induced by CPT-11 in this small observational study, and further study with a larger sample size, including potentially randomized trials, is suggested.