B Cells Are the Dominant Antigen-Presenting Cells that Activate Naive CD4+ T Cells upon Immunization with a Virus-Derived Nanoparticle Antigen.

B cells can present antigens to CD4+ T cells, but it is thought that dendritic cells (DCs) are the primary initiators of naive CD4+ T cell responses. Nanoparticles, including virus-like particles (VLPs), are attractive candidates as carriers for vaccines and drug delivery. Using RNA phage Qß-derived VLP (Qß-VLP) as a model antigen, we found that antigen-specific B cells were the dominant antigen-presenting cells that initiated naive CD4+ T cell activation. B cells were sufficient to induce T follicular helper cell development in the absence of DCs. Qß-specific B cells promoted CD4+ T cell proliferation and differentiation via cognate interactions and through Toll-like receptor signaling-mediated cytokine production. Antigen-specific B cells were also involved in initiating CD4+ T cell responses during immunization with inactivated influenza virus. These findings have implications for the rational design of nanoparticles as vaccine candidates, particularly for therapeutic vaccines that aim to break immune tolerance.

Top-down versus bottom-up oxidation of a neonicotinoid pesticide by OH radicals.

Emerging contaminants (EC) distributed on surfaces in the environment can be oxidized by gas phase species (top-down) or by oxidants generated by the underlying substrate (bottom-up). One class of EC is the neonicotinoid (NN) pesticides that are widely distributed in air, water, and on plant and soil surfaces as well as on airborne dust and building materials. This study investigates the OH oxidation of the systemic NN pesticide acetamiprid (ACM) at room temperature. ACM on particles and as thin films on solid substrates were oxidized by OH radicals either from the gas phase or from an underlying TiO2 or NaNO2 substrate, and for comparison, in the aqueous phase. The site of OH attack is both the secondary >CH2 group as well as the primary -CH3 group attached to the tertiary amine nitrogen, with the latter dominating. In the case of top-down oxidation of ACM by gas phase OH radicals, addition to the -CN group also occurs. Major products are carbonyls and alcohols, but in the presence of sufficient water, their hydrolyzed products dominate. Kinetics measurements show ACM is more reactive toward gas phase OH radicals than other NN nitroguanidines, with an atmospheric lifetime of a few days. Bottom-up oxidation of ACM on TiO2 exposed to sunlight outdoors (temperatures were above 30 °C) was also shown to occur and is likely to be competitive with top-down oxidation. These findings highlight the different potential oxidation processes for EC and provide key data for assessing their environmental fates and toxicologies.

Genome-wide association and Mendelian randomisation analysis among 30,699 Chinese pregnant women identifies novel genetic and molecular risk factors for gestational diabetes and glycaemic traits.

AIMS/HYPOTHESIS: Gestational diabetes mellitus (GDM) is the most common disorder in pregnancy; however, its underlying causes remain obscure. This study aimed to investigate the genetic and molecular risk factors contributing to GDM and glycaemic traits. METHODS: We collected non-invasive prenatal test (NIPT) sequencing data along with four glycaemic and 55 biochemical measurements from 30,699 pregnant women during a 2 year period at Shenzhen Baoan Women's and Children's Hospital in China. Genome-wide association studies (GWAS) were conducted between genotypes derived from NIPTs and GDM diagnosis, baseline glycaemic levels and glycaemic levels after glucose challenges. In total, 3317 women were diagnosed with GDM, while 19,565 served as control participants. The results were replicated using two independent cohorts. Additionally, we performed one-sample Mendelian randomisation to explore potential causal associations between the 55 biochemical measurements and risk of GDM and glycaemic levels. RESULTS: We identified four genetic loci significantly associated with GDM susceptibility. Among these, MTNR1B exhibited the highest significance (rs10830963-G, OR [95% CI] 1.57 [1.45, 1.70], p=4.42×10-29), although its effect on type 2 diabetes was modest. Furthermore, we found 31 genetic loci, including 14 novel loci, that were significantly associated with the four glycaemic traits. The replication rates of these associations with GDM, fasting plasma glucose levels and 0 h, 1 h and 2 h OGTT glucose levels were 4 out of 4, 6 out of 9, 10 out of 11, 5 out of 7 and 4 out of 4, respectively. Mendelian randomisation analysis suggested that a genetically regulated higher lymphocytes percentage and lower white blood cell count, neutrophil percentage and absolute neutrophil count were associated with elevated glucose levels and an increased risk of GDM. CONCLUSIONS/INTERPRETATION: Our findings provide new insights into the genetic basis of GDM and glycaemic traits during pregnancy in an East Asian population and highlight the potential role of inflammatory pathways in the aetiology of GDM and variations in glycaemic levels. DATA AVAILABILITY: Summary statistics for GDM; fasting plasma glucose; 0 h, 1 h and 2h OGTT; and the 55 biomarkers are available in the GWAS Atlas (study accession no.: GVP000001, https://ngdc.cncb.ac.cn/gwas/browse/GVP000001) .

Treatment for Gorham-Stout syndrome with a combination of teriparatide and denosumab.

Gorham-Stout syndrome is an aggressive, non-hereditary, and rare disease affecting bone metabolism. Its etiology and pathogenesis remain elusive. The syndrome manifests with diverse clinical symptoms, often leading to frequent misdiagnoses and presenting challenges in treatment. In this study, we report a case of cranial and maxillary osteolysis in a 47-year-old female patient with somatic mutations in the VEGF-A, VEGF-B, and VEGF-C genes and the EPHB4 gene. After treatment with bisphosphonates, this patient still had persistent resorption of the mandible, but switching to a teriparatide and denosumab combination yielded substantial improvement. This study is the first report to show that teriparatide combined with denosumab can be used to treat Gorham-Stout syndrome.

Apolipoprotein E E3/E4 genotype is associated with an increased risk of type 2 diabetes mellitus complicated with coronary artery disease.

OBJECTIVE: Dyslipidemia is a co-existing problem in patients with diabetes mellitus (DM) and coronary artery disease (CAD), and apolipoprotein E (APOE) plays an important role in lipid metabolism. However, the relationship between the APOE gene polymorphisms and the risk of developing CAD in type 2 DM (T2DM) patients remains controversial. The aim of this study was to assess this relationship and provide a reference for further risk assessment of CAD in T2DM patients. METHODS: The study included 378 patients with T2DM complicated with CAD (T2DM + CAD) and 431 patients with T2DM alone in the case group, and 351 individuals without DM and CAD were set as controls. The APOE rs429358 and rs7412 polymorphisms were genotyped by polymerase chain reaction (PCR) - microarray. Differences in APOE genotypes and alleles between patients and controls were compared. Multiple logistic regression analysis was performed after adjusting for age, gender, body mass index (BMI), history of smoking, and history of drinking to access the relationship between APOE genotypes and T2DM + CAD risk. RESULTS: The frequencies of the APOE ɛ3/ɛ4 genotype and ε4 allele were higher in the T2DM + CAD patients, and the frequencies of the APOE ɛ3/ɛ3 genotype and ε3 allele were lower than those in the controls (all p < 0.05). The T2DM + CAD patients with ɛ4 allele had higher level in low-density lipoprotein cholesterol (LDL-C) than those in patients with ɛ2 and ɛ3 allele (p < 0.05). The results of logistic regression analysis showed that age ≥ 60 years old, and BMI ≥ 24.0 kg/m2 were independent risk factors for T2DM and T2DM + CAD, and APOE ɛ3/ɛ4 genotype (adjusted odds ratio (OR) = 1.93, 95% confidence interval (CI) = 1.18-3.14, p = 0.008) and ɛ4 allele (adjusted OR = 1.97, 95% CI = 1.23-3.17) were independent risk factors for T2DM + CAD. However, the APOE genotypes and alleles were not found to have relationship with the risk of T2DM. CONCLUSIONS: APOE ε3/ε4 genotype and ε4 allele were independent risk factors for T2DM complicated with CAD, but not for T2DM.

Talaromides A-C, Bioactive Cyclic Heptapeptides from Talaromyces siglerae Isolated from a Marine Sponge.

Three new cyclic heptapeptides, talaromides A-C (1-3), were isolated from cultures produced by the fungus Talaromyces siglerae (Ascomycota), isolated from an unidentified sponge. The structures, featuring an unusual proline-anthranilic moiety, were elucidated by analysis of spectroscopic data and chemical transformations, including the advanced Marfey's method and GITC derivatization. Talaromides A and B inhibited migration activity against PANC-1 human pancreatic cancer cells without significant cytotoxicity.

Cavomycins A-C, Linear Oligomer Depsipeptides from an Annelid-Associated Streptomyces cavourensis.

Three unique linear oligomeric depsipeptides, designated as cavomycins A-C (1-3), were identified from Streptomyces cavourensis, a gut bacterium associated with the annelid Paraleonnates uschakovi. The structures of these depsipeptides were determined through a combination of spectroscopic methods and chemical derivatization techniques, including methanolysis, the modified Mosher's method, advanced Marfey's methods, and phenylglycine methyl ester derivatization. The unique dipeptidyl residue arrangements in compounds 1-3 indicate that they are not degradation products of valinomycin. Compound 2 and its methylation derivative 2a exhibited antiproliferative activity against PANC-1 pancreatic cancer cells with IC50 values of 1.2 and 1.7 µM, respectively.

Influence of Helicobacter pylori Infection and Eradication on Small Intestinal Bacterial Overgrowth and Abdominal Symptoms.

BACKGROUND: The relationship between Helicobacter pylori (H. pylori) infection and small intestinal bacterial overgrowth (SIBO) has attracted attention recently. AIMS: To analyze the influence of H. pylori infection and eradication on SIBO, IMO, and abdominal symptoms. METHODS: Patients with gastrointestinal symptoms were tested for 13C urea breath test and if positive, treated with bismuth-based quadruple therapy. Lactulose hydrogen methane breath test (HMBT) was performed and symptoms were assessed using gastrointestinal symptom rating scale (GSRS) before and 6 weeks after eradication. RESULTS: Of the 102 subjects, 53 were H. pylori positive. The prevalence of SIBO and IMO were higher in patients with H. pylori infection than in those without infection (49.1% vs 24.5%, P = 0.019 for SIBO; 24.5% vs 8.2%, P = 0.027 for IMO). GSRS scores were similar between H. pylori-infected and uninfected patients (2 (IQR: 1;3) vs 2 (IQR: 1;2), P = 0.211). Patients with SIBO or IMO presented higher GSRS scores than patients with both SIBO and IMO negative (2 (IQR: 2;3), 2 (IQR: 2;3) vs 2 (IQR: 1;2), P = 0.011, 0.001, respectively). For the 50 patients who successfully eradicated H. pylori, the response rates for SIBO and IMO were 66.7% and 76.9%, respectively. GSRS scores also significantly decreased (2 (IQR: 1;3) to 0 (IQR: 0;1), P < 0.001) after eradication. CONCLUSION: Helicobacter pylori infection was associated with higher prevalence of SIBO and IMO, both of which led to more pronounced abdominal symptoms. H. pylori eradication also achieved therapeutic effects on SIBO and IMO, accompanied by relief of abdominal symptoms.

Comparative clinical study of phosphorous necrosis and medical-related osteonecrosis of the jaws.

BACKGROUND: Phosphorous necrosis of the jaw (PNJ) exhibits similar clinical and pathological features as medical-related osteonecrosis of the jaw (MRONJ). This study aims at comparing the similarities and differences between PNJ and MRONJ regarding pathological features and to provide a theoretical basis for the clinical diagnosis and management of PNJ. MATERIAL AND METHODS: A retrospective analysis was conducted to assess clinical differences among 38 PNJ patients and 31 MRONJ patients, who were diagnosed and treated between January 2009 and October 2022. Pathological alterations in bone tissue were evaluated using EDS, H&E, Masson, and TRAP staining on five specimens from both MRONJ and PNJ cases; furthermore, immunohistochemistry was used to determine the expression levels of OPG, RANKL, and Runx2. The mandibular coronoid process was removed from individuals with temporomandibular joint ankylosis to serve as a control. RESULTS: CBCT imaging demonstrated necrotic bone formation in block, strip, or plaque shapes. EDS analysis showed that the calcium/phosphorus ratio in the bone tissue of PNJ and MRONJ was significantly lower than that of the control group (P < 0.05). Additionally, staining indicated reduced osteoblast counts, disrupted bone trabecular structure, and decreased collagen fiber content in the bone tissues of PNJ and MRONJ. Immunohistochemistry demonstrated that RANKL expression was significantly lower in MRONJ compared to PNJ and control groups (P < 0.05). Conversely, Runx2 expression was significantly higher in PNJ than in MRONJ and control groups (P < 0.05), and there was no significant difference in OPG expression. CONCLUSION: PNJ and MRONJ demonstrate comparable clinical manifestations and pathological traits, although disparities may exist in their underlying exhibit comparable clinical manifestations, pathological traits, and molecular mechanisms.

Wall-associated kinase BrWAK1 confers resistance to downy mildew in Brassica rapa.

The plant cell wall is the first line of defence against physical damage and pathogen attack. Wall-associated kinase (WAK) has the ability to perceive the changes in the cell wall matrix and transform signals into the cytoplasm, being involved in plant development and the defence response. Downy mildew, caused by Hyaloperonospora brassicae, can result in a massive loss in Chinese cabbage (Brassica rapa L. ssp. pekinensis) production. Herein, we identified a candidate resistant WAK gene, BrWAK1, in a major resistant quantitative trait locus, using a double haploid population derived from resistant inbred line T12-19 and the susceptible line 91-112. The expression of BrWAK1 could be induced by salicylic acid and pathogen inoculation. Expression of BrWAK1 in 91-112 could significantly enhance resistance to the pathogen, while truncating BrWAK1 in T12-19 increased disease susceptibility. Variation in the extracellular galacturonan binding (GUB) domain of BrWAK1 was found to mainly confer resistance to downy mildew in T12-19. Moreover, BrWAK1 was proved to interact with BrBAK1 (brassinosteroid insensitive 1 associated kinase), resulting in the activation of the downstream mitogen-activated protein kinase (MAPK) cascade to trigger the defence response. BrWAK1 is the first identified and thoroughly characterized WAK gene conferring disease resistance in Chinese cabbage, and the plant biomass is not significantly influenced by BrWAK1, which will greatly accelerate Chinese cabbage breeding for downy mildew resistance.

Bioactive Piperazic Acid-Bearing Cyclodepsipeptides, Lydiamycins E-H, from an Endophytic Streptomyces sp. Associated with Cinnamomum cassia.

A chemical investigation of the endophytic Streptomyces sp. HBQ95, associated with the medicinal plant Cinnamomum cassia Presl, enabled the discovery of four new piperazic acid-bearing cyclodepsipeptides, lydiamycins E-H (1-4), and one known compound (lydiamycin A). Their chemical structures, including absolute configurations, were defined by a combination of spectroscopic analyses and multiple chemical manipulations. Lydiamycins F-H (2-4) and A (5) exhibited antimetastatic activity against PANC-1 human pancreatic cancer cells without significant cytotoxicity.

Congenital mandibular coronoid process hyperplasia and associated diseases.

Coronoid process hyperplasia (CPH) is an oral and maxillofacial surgical disease that can result in restricted jaw movement due to an enlarged and elongated mandibular coronoid process. It is characterized by the painless progressive restriction of unilaterally or bilaterally mouth opening. Clinically, unexplained bilateral CPH is less common and therefore often overlooked or misdiagnosed, and coronoidectomy can be very effective on improving mouth opening. Currently, the exact etiology and mechanism of congenital CPH have not yet been fully understood, but it is generally believed to be genetically related. In this paper, the relationship of the congenital mandibular CPH with the related diseases was examined based on cases collected in our clinic and literature review for the clinical diagnosis and treatment of patients with restricted mouth opening associated with CPH.

Extracellular matrix of ameloblastoma-derived negatively regulates osteogenic differentiation.

OBJECTIVE: To investigate the effects of key pathogenic genes involved in the development of jaw ameloblastoma (AB) and its associated extracellular matrix (ECM) on osteogenic differentiation in order to provide a theoretical foundation for future research into bone aggressiveness of AB. METHODS: The essential genes were identified by five AB patients for whole-exome sequencing and the microarray datasets GES38494 and GES132472. Moreover, the expression of key genes and their encoded proteins in AB tissues was explored. In addition, AB-derived the decellularized ECM (ABdECM) tissues were generated by the decellularization technique. Furthermore, the osteogenic development of periodontal ligament stem cells (PDLSCs) was mimicked by simulating the effects of the AB tumor microenvironment (TME). RESULTS: The AB essential genes including COL1A2, COL4A2, FBN1, and HPSE were discovered. Among them, the expression of HPSE was down-regulated, while that of COL1A2, COL4A2, and FBN1 was noticeably upregulated in AB compared with normal gingival tissues of the jaws. In vitro osteogenic differentiation of PDLSCs was suppressed by the ABdECM. CONCLUSIONS: Abnormal ECM proteins encoded by COL4A2, COL1A2, FBN1, and HPSE genes can cause disturbance in the ECM environment of AB and promote bone resorption.

Unexpected formation of oxygen-free products and nitrous acid from the ozonolysis of the neonicotinoid nitenpyram.

The neonicotinoid nitenpyram (NPM) is a multifunctional nitroenamine [(R1N)(R2N)C=CHNO2] pesticide. As a nitroalkene, it is structurally similar to other emerging contaminants such as the pharmaceuticals ranitidine and nizatidine. Because ozone is a common atmospheric oxidant, such compounds may be oxidized on contact with air to form new products that have different toxicity compared to the parent compounds. Here we show that oxidation of thin solid films of NPM by gas-phase ozone produces unexpected products, the majority of which do not contain oxygen, despite the highly oxidizing reactant. A further surprising finding is the formation of gas-phase nitrous acid (HONO), a species known to be a major photolytic source of the highly reactive hydroxyl radical in air. The results of application of a kinetic multilayer model show that reaction was not restricted to the surface layers but, at sufficiently high ozone concentrations, occurred throughout the film. The rate constant derived for the O3-NPM reaction is 1 × 10-18 cm3⋅s-1, and the diffusion coefficient of ozone in the thin film is 9 × 10-10 cm2⋅s-1 These findings highlight the unique chemistry of multifunctional nitroenamines and demonstrate that known chemical mechanisms for individual moieties in such compounds cannot be extrapolated from simple alkenes. This is critical for guiding assessments of the environmental fates and impacts of pesticides and pharmaceuticals, and for providing guidance in designing better future alternatives.

[Realization of Long Bone Stitching Technology in DR Chest Radiography System].

OBJECTIVE: Using a common DR chest radiography system to realize a long bone stitching technology. METHODS: Introduce the role of long bone stitching technology in medical diagnosis and treatment, and the principle of long bone stitching technology to make a long bone stitching radiographic device, and combine with the chest radiography system to take the long bone stitching image experiment. RESULTS: The hospitals of class Ⅱ (or more lower levels) can realize the long bone stitching technology using a common DR chest radiography system. CONCLUSIONS: Using this technology can save the hospital costs, reduce the burden on patients, achieve good social and economic benefits.

Chinese Consensus Report on Family-Based Helicobacter pylori Infection Control and Management (2021 Edition).

OBJECTIVE: Helicobacter pylori infection is mostly a family-based infectious disease. To facilitate its prevention and management, a national consensus meeting was held to review current evidence and propose strategies for population-wide and family-based H. pylori infection control and management to reduce the related disease burden. METHODS: Fifty-seven experts from 41 major universities and institutions in 20 provinces/regions of mainland China were invited to review evidence and modify statements using Delphi process and grading of recommendations assessment, development and evaluation system. The consensus level was defined as ≥80% for agreement on the proposed statements. RESULTS: Experts discussed and modified the original 23 statements on family-based H. pylori infection transmission, control and management, and reached consensus on 16 statements. The final report consists of three parts: (1) H. pylori infection and transmission among family members, (2) prevention and management of H. pylori infection in children and elderly people within households, and (3) strategies for prevention and management of H. pylori infection for family members. In addition to the 'test-and-treat' and 'screen-and-treat' strategies, this consensus also introduced a novel third 'family-based H. pylori infection control and management' strategy to prevent its intrafamilial transmission and development of related diseases. CONCLUSION: H. pylori is transmissible from person to person, and among family members. A family-based H. pylori prevention and eradication strategy would be a suitable approach to prevent its intra-familial transmission and related diseases. The notion and practice would be beneficial not only for Chinese residents but also valuable as a reference for other highly infected areas.

Diagnosis and treatment of Helicobacter pylori infection by physicians in China: A nationwide cross-sectional study.

BACKGROUND: To investigate the current state of knowledge and practice of Helicobacter pylori (H. pylori) infection management in China. MATERIALS AND METHODS: This nationwide, multicenter, cross-sectional questionnaire survey was conducted between March and April 2021 with respect to the diagnosis and treatment of H. pylori infection in 31 provinces, encompassing over 1000 hospitals in mainland China. General physician information, diagnostic and detection status, eradication treatment, reexamination and follow-up after treatment, and basic knowledge of physicians were collected and compared with the Fifth Chinese National Consensus Report on Management of H. pylori infection and the 2016 Maastricht V/Florence guidelines. The subgroup analysis was also performed. RESULTS: Of the 6873 questionnaire respondents, 48.8% were males, and 51.2% were females. Approximately, 26.5% of respondents indicated that their hospitals had dedicated clinics for managing H. pylori infection. Moreover, 88.0% of respondents prescribed a bismuth-containing quadruple regimen as the initial eradication treatment, and 92.7% deemed the gastric acid suppression critical. Furthermore, 91.0% of respondents routinely recommended a reexamination 1-2 months after eradication therapy, and 95.1% advised patients to stop PPI treatment at least 2 weeks before reexamination. The detail of following (the choice of target population/methods; the choice/availability of drugs/regimens, indications for eradication, factors influencing eradication efficacy/improvement methods and factors influencing adherence, management options/factors influencing relapse; the timing and methods, awareness of reinfection rates/prevention measures, and the approach to continuing education, awareness of guidelines, and acceptance of current core concepts of management) was also described. Subgroup analysis further revealed that significant differences were existed in being gastroenterologist or not, different education level, professional title, years of working, and provincial administrative regions. CONCLUSIONS: Chinese physicians' skills and knowledge about the diagnosis and treatment of H. pylori infection could be improved. More works on education are needed in future.

Study on the effectiveness of modified colonoscopy nursing pads in colonoscopy.

OBJECTIVE: To investigate the effect of modified colonoscopy nursing pads in colonoscopy. METHODS: A total of 262 subjects who underwent colonoscopy at our endoscopy center between September 1, 2021 and February 28, 2022 were selected and randomly divided into a control group and an experimental group, with 131 cases in each group. The control group used conventional nursing pads, while the experimental group used modified nursing pads. The success rate of the first correct position, the time spent by the nurse to guide the correct position, the bed unit contamination rate, the contamination rate of the operator's protective equipment, the privacy protection of the examinees and the satisfaction degree after the examination were compared between the two groups. RESULTS: The success rate of the first correct position of the examinees in the experimental group was significantly higher than that of the control group (P < 0.05), and the time spent by the nurses to guide the correct position in the experimental group was less than that of the control group (P < 0.05). The bed unit contamination rate and operator's protective equipment contamination rate of the experimental group were lower than those of the control group, and the satisfaction degree of the examinees was higher in the experimental group than in the control group, and the differences were statistically significant (P < 0.05). CONCLUSION: The modified colonoscopy nursing pad can save the time of correct colonoscopy positioning of examinees, improve the efficiency of colonoscopy, reduce the workload of nursing staff, effectively protect the privacy of patients, reduce the bed unit contamination and protective equipment contamination, and then improve the comfort and satisfaction of patients.

External validation of two prediction models for adequate bowel preparation in Asia: a prospective study.

BACKGROUND: Several models for predicting adequate bowel preparation are available but have never been externally validated. The aim of this study is to compare the available models in an independent population. METHODS: This study prospectively recruited 500 consecutive patients from August to December 2020 from the Endoscopy Center of a tertiary hospital. All patients underwent the same bowel preparation regimen. The discrimination of the prediction models was quantified with the area under the receiver operating characteristic curve (AUC), and the 95% confidence interval (CI) was calculated for each AUC. RESULTS: Finally, 461 patients were eligible for this study. A total of 110 (23.9%) patients were deemed to show inadequate bowel preparation during colonoscopy. There were significant differences between patients with and without adequate bowel preparation in terms of current hospitalization, procedure time, comorbidities (including diabetes and constipation), American Society of Anesthesiologists Physical Status Classification System score (ASA) ≥ 3, medication usage, and abdominal/pelvic surgery. The prediction models performed as follows: the Dik ≥ 2 model, the Dik ≥ 3 model, and the Antonio > 1.225 model had AUCs of 0.660 (95% CI = 0.604-0.717), 0.691 (95% CI = 0.646-0.733), and 0.645 (95% CI = 0.615-0.704), respectively. Comparison of the two prediction models showed no significant improvement (Antonio > 1.225 vs. Dik ≥ 3, 1.801, 95% CI = -0.004-0.096, P = 0.072). CONCLUSIONS: Both models are potentially helpful. However, it is necessary to develop or improve a prediction model to obtain a more suitable and detailed model. TRIAL REGISTRATION: ClinicalTrials.gov, Number NCT04607161.

Gas Phase and Gas-Solid Interface Ozonolysis of Nitrogen Containing Alkenes: Nitroalkenes, Enamines, and Nitroenamines.

Emerging contaminants are of concern due to their rapidly increasing numbers and potential ecological and human health effects. In this study, the synergistic effects of the presence of multifunctional nitro, amino and carbon-carbon double bond (C═C) groups on the gas phase ozonolysis in O2 or at the air/solid interface were investigated using five simple model compounds. The gas phase ozonolysis rate constants at 296 K were (3.5 ± 0.9) × 10-20 cm3 molecule-1 s-1 for 2-methyl-1-nitroprop-1-ene and (6.8 ± 0.8) × 10-19 cm3 molecule-1 s-1 for 4-methyl-4-nitro-1-pentene, with lifetimes of 134 and 7 days in the presence of 100 ppb ozone in the atmosphere, respectively. The rate constants for gas phase E-N,N-dimethyl-1-propenylamine and N,N-dimethylallylamine reactions with ozone were too fast (>10-18 cm3 molecule-1 s-1) to be measured, implying lifetimes of less than 5 days. A multiphase kinetics model (KM-GAP) was used to probe the gas-solid kinetics of 1-dimethylamino-2-nitroethylene, yielding a rate constant for the surface reaction of 1.8 × 10-9 cm2 molecule-1 s-1 and in the bulk 1× 10-16 cm3 molecule-1 s-1. These results show that a nitro group attached to the C═C lowers the gas phase rate constant by 2-3 orders of magnitude compared to the simple alkenes, while amino groups have the opposite effect. The presence of both groups provides counterbalancing effects. Products with deleterious health effects including dimethylformamide and formaldehyde were identified by FTIR. The identified products differentiate whether the initial site of ozone attack is C═C and/or the amino group. This study provides a basis for predicting the environmental fates of emerging contaminants and shows that both the toxicity of both the parent compounds and the products should be taken into account in assessing their environmental impacts.