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1.
Int J Ophthalmol ; 17(3): 537-544, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38721498

RESUMEN

AIM: To identify the differential methylation sites (DMS) and their according genes associated with diabetic retinopathy (DR) development in type 1 diabetes (T1DM) children. METHODS: This study consists of two surveys. A total of 40 T1DM children was included in the first survey. Because no participant has DR, retina thinning was used as a surrogate indicator for DR. The lowest 25% participants with the thinnest macular retinal thickness were included into the case group, and the others were controls. The DNA methylation status was assessed by the Illumina methylation 850K array BeadChip assay, and compared between the case and control groups. Four DMS with a potential role in diabetes were identified. The second survey included 27 T1DM children, among which four had DR. The methylation patterns of the four DMS identified by 850K were compared between participants with and without DR by pyrosequencing. RESULTS: In the first survey, the 850K array revealed 751 sites significantly and differentially methylated in the case group comparing with the controls (|Δß|>0.1 and Adj.P<0.05), and 328 of these were identified with a significance of Adj.P<0.01. Among these, 319 CpG sites were hypermethylated and 432 were hypomethylated in the case group relative to the controls. Pyrosequencing revealed that the transcription elongation regulator 1 like (TCERG1L, cg07684215) gene was hypermethylated in the four T1DM children with DR (P=0.018), which was consistent with the result from the first survey. The methylation status of the other three DMS (cg26389052, cg25192647, and cg05413694) showed no difference (all P>0.05) between participants with and without DR. CONCLUSION: The hypermethylation of the TCERG1L gene is a risk factor for DR development in Chinese children with T1DM.

2.
J Dig Dis ; 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38676317

RESUMEN

OBJECTIVES: Synchronous adenomas of the major and minor duodenal papilla are seldom reported. The aim of this study was to describe the characteristics of synchronous major and minor papilla adenomas and to evaluate the safety and efficacy of endoscopic papillectomy (EP) for the management of the disease. METHODS: Consecutive patients who underwent endoscopy for synchronous major and minor papilla adenomas from January 1, 2013 to August 31, 2023 were analyzed retrospectively. Patients' characteristics, clinical manifestations, laboratory, imaging and endoscopic findings were collected. RESULTS: The nine patients with synchronous major and minor papilla adenomas had an average age of 50.78 ± 10.70 years. The diameter of major and minor papilla adenomas was 12.11 ± 3.41 mm and 6.11 ± 1.05 mm, respectively. Most major papilla adenomas had R0 horizontal margins (n = 8), while R0 vertical margins were achieved in all patients. While minor papilla adenomas were resected with both R0 horizontal and vertical margins in all patients. Post-EP bleeding was observed in one patient, which was classified as mild. Post-EP hyperamylasemia and pancreatitis was observed in two and four patients, respectively; the latter consisted of three with mild pancreatitis and one with severe pancreatitis. No perforation was observed. The mean follow-up duration was 9.22 ± 5.99 months. Histologically confirmed recurrence at the resection site was detected in one patient at 3 months after the procedure. CONCLUSIONS: Synchronous major and minor papilla adenomas may not be as rare as previously speculated. EP may be an effective and safe alternative modality for their management.

3.
Chemistry ; : e202400995, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38600034

RESUMEN

Introduction of the trifluoromethyl (CF3) group into organic compounds has garnered substantial interest because of its significant role in pharmaceuticals and agrochemicals. Here, we report a hydroxylamine-mediated radical process for C(sp2)-H trifluoromethylation of terminal alkenes. The reaction shows good reactivity, impressive E/Z selectivity (up to >20 : 1), and broad functional group compatibility. Expansion of this approach to perfluoroalkylation and late-stage trifluoromethylation of bioactive molecules demonstrates its promising application potential. Mechanistic studies suggest that the reaction follows a radical addition and subsequent elimination pathway.

4.
Clin Appl Thromb Hemost ; 30: 10760296241238015, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38529627

RESUMEN

To investigate the effect of reduced early-pregnancy activated partial thrombin time (APTT), prothrombin time (PT), and international standardized ratio (INR) on the risk of preeclampsia. A total of 8549 pregnant women with singleton births were included. Early pregnancy APTT, PT, and INR levels, with age, birth, prepregnancy body mass index, fibrinogen (FBG), thrombin time (TT), D-dimer (DD2), antithrombin III (ATIII), fibrin degradation products (FDP) as confounders, generalized linear model of APTT, the relative risk of PT and INR when INR reduction. After adequate adjustment for confounders, the relative risk of preeclampsia was 0.703 for every 1 s increase in plasma PT results in early pregnancy, and for every 0.1 increase in plasma INR results, the relative risk of preeclampsia was 0.767. With a PT less than the P25 quantile (<11 s), the relative risk of preeclampsia was 1.328. The relative risk of preeclampsia at an INR less than the P25 quantile (<0.92) was 1.24. There was no statistical association between APTT on the risk of preeclampsia. The relative risk of preeclampsia is strongly associated with a decrease in PT and INR in early pregnancy. PT and INR in early pregnancy were a potential marker in the risk stratification of preeclampsia. Focusing on reduced PT and INR levels in early pregnancy can help to identify early pregnancies at risk for preeclampsia.


Asunto(s)
Preeclampsia , Humanos , Femenino , Embarazo , Relación Normalizada Internacional , Preeclampsia/epidemiología , Estudios Retrospectivos , Pruebas de Coagulación Sanguínea , Tiempo de Protrombina , Tiempo de Tromboplastina Parcial
5.
J Am Chem Soc ; 146(13): 9335-9346, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38501695

RESUMEN

Controlling product selectivity in successive reactions of the same type is challenging owing to the comparable thermodynamic and kinetic properties of the reactions involved. Here, the synergistic interaction of the two phosphoryl groups in bisphosphine dioxides (BPDOs) with a bromo-phosphonium cation was studied experimentally to provide a practical tool for substrate-catalyst recognition. As the eventual result, we have developed a phosphonium-catalyzed monoreduction of chiral BPDOs to access an array of synthetically useful bisphosphine monoxides (BPMOs) with axial, spiro, and planar chirality, which are otherwise challenging to synthesize before. The reaction features excellent selectivity and impressive reactivity. It proceeds under mild conditions, avoiding the use of superstoichiometric amounts of additives and metal catalysts to simplify the synthetic procedure. The accessibility and scalability of the reaction allowed for the rapid construction of a ligand library for optimization of asymmetric Heck-type cyclization, laying the foundation for a broad range of applications of chiral BPMOs in catalysis.

6.
Heliyon ; 10(3): e25409, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38327465

RESUMEN

Background/Objective: Reticulocyte hemoglobin content (MCHr) was recognized as a rapid and reliable marker for investigating iron deficiency (ID). We hypothesized that MCHr was associated with the risk of iron deficiency anemia in adults. Methods: This is a dual-center case-control study. A total of 806 patients and healthy individuals were recruited from Ruijin Hospital and Xinhua Hospital affiliated to Shanghai Jiaotong University School of Medicine between January 2021 and December 2021. The participants were categorized into iron deficiency anemia (IDA) group (n = 302), non-IDA group (n = 366), and healthy control group (n = 138). According to the MCHr level, the participants were divided into two groups, i.e. normal MCHr (≥25 pg) and decreased MCHr (<25 pg) group. Multivariate logistic regression analysis and adjusted subgroup analysis were conducted to estimate the relative risk between MCHr and IDA, with confounding factors including age, sex, hemoglobin (Hb), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), Hematocrit (HCT), serum iron (Fe), ferritin (Ferrit), and total iron binding capacity (TIBC). Results: Compared with the non-IDA, the MCHr level with IDA decreased significantly. ROC curve analysis showed that MCHr had the largest area under the AUC curve. After comprehensive adjustment for confounding factors, individuals with normal level of MCHr exhibited a decreased risk of IDA (OR = 0.68 [0.60, 0.77], P < 0.01), while the risk of IDA was up to 5 times higher for those with decreased MCHr. Conclusion: Our findings supported the hypothesis that MCHr was associated with the risk of IDA in adults and could serve as an indicator of IDA severity. MCHr holds clinical value as an auxiliary diagnostic indicator, providing valuable insights into whether invasive examinations are warranted in the assessment of IDA.

7.
BMC Gastroenterol ; 24(1): 84, 2024 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-38395762

RESUMEN

BACKGROUND: The activation of hepatic stellate cells (HSCs) has been emphasized as a leading event of the pathogenesis of liver cirrhosis, while the exact mechanism of its activation is largely unknown. Furthermore, the novel non-invasive predictors of prognosis in cirrhotic patients warrant more exploration. miR-541 has been identified as a tumor suppressor in hepatocellular carcinoma and a regulator of fibrotic disease, such as lung fibrosis and renal fibrosis. However, its role in liver cirrhosis has not been reported. METHODS: Real-time PCR was used to detect miR-541 expression in the liver tissues and sera of liver cirrhosis patients and in the human LX-2. Gain- and loss-of-function assays were performed to evaluate the effects of miR-541 on the activation of LX-2. Bioinformatics analysis and a luciferase reporter assay were conducted to investigate the target gene of miR-541. RESULTS: miR-541 was downregulated in the tissues and sera of patients with liver cirrhosis, which was exacerbated by deteriorating disease severity. Importantly, the lower expression of miR-541 was associated with more episodes of complications including ascites and hepatic encephalopathy, a shorter overall lifespan, and decompensation-free survival. Moreover, multivariate Cox's regression analysis verified lower serum miR-541 as an independent risk factor for liver-related death in cirrhotic patients (HR = 0.394; 95% CI: 0.164-0.947; P = 0.037). miR-541 was also decreased in LX-2 cells activated by TGF-ß and the overexpression of miR-541 inhibited the proliferation, activation and hydroxyproline secretion of LX-2 cells. JAG2 is an important ligand of Notch signaling and was identified as a direct target gene of miR-541. The expression of JAG2 was upregulated in the liver tissues of cirrhotic patients and was inversely correlated with miR-541 levels. A rescue assay further confirmed that JAG2 was involved in the function of miR-541 when regulating LX-2 activation and Notch signaling. CONCLUSIONS: Dysregulation of miR-541/JAG2 axis might be a as a new mechanism of liver fibrosis, and miR-541 could serve as a novel non-invasive biomarker and therapeutic targets for liver cirrhosis.


Asunto(s)
Células Estrelladas Hepáticas , Cirrosis Hepática , MicroARNs , Humanos , Proliferación Celular/genética , Células Estrelladas Hepáticas/metabolismo , Proteína Jagged-2/metabolismo , Proteína Jagged-2/farmacología , Cirrosis Hepática/genética , Cirrosis Hepática/metabolismo , Cirrosis Hepática/patología , MicroARNs/genética , MicroARNs/metabolismo , Pronóstico
8.
Drug Metab Dispos ; 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38302428

RESUMEN

The mammalian gut microbiota plays diverse and essential roles in modulating host physiology. Key mediators determining the outcome of the microbiota-host interactions are the small molecule metabolites produced by the gut microbiota. The liver is the organ massively exposed to gut microbial metabolites, and it serves as the nexus, maintaining healthy interactions between the gut microbiota and host. At the same time, the liver is the primary target of harmful gut microbial metabolites. This review provides an up-to-date list of gut microbial metabolites identified to increase or decrease host susceptibility to APAP-induced liver injury. Signaling pathways and molecular factors involved in the progression of APAP-induced hepatotoxicity are well-established, and we propose that the mouse model of APAP-induced hepatotoxicity serves as an excellent system for uncovering gut microbial metabolites of previously unknown function. Moreover, we envision that gut microbial metabolites identified to alter APAP-induced hepatotoxicity likely have broader implications in other liver diseases. Significance Statement This review provides an overview of recent discoveries from investigating whether and how the gut microbiota modulates the host susceptibility to APAP-induced liver injury. It focuses on the roles of gut bacterial small molecule metabolites as mediators of the interaction between the gut microbiota and the liver. It also illustrates the utility of APAP-induced liver injury as a model to identify gut microbial metabolites with biological function.

9.
Clin Genet ; 105(4): 397-405, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38173219

RESUMEN

CCDC88C gene, which encodes coiled-coil domain containing 88C, is essential for cell communication during neural development. Variants in the CCDC88C caused congenital hydrocephalus, some accompanied by seizures. In patients with epilepsy without acquired etiologies, we performed whole-exome sequencing (trio-based). Two de novo and two biallelic CCDC88C variants were identified in four cases with focal (partial) epilepsy. These variants did not present or had low frequencies in the gnomAD populations and were predicted to be damaging by multiple computational algorithms. Patients with de novo variants presented with adult-onset epilepsy, whereas patients with biallelic variants displayed infant-onset epilepsy. They all responded well to anti-seizure medications and were seizure-free. Further analysis showed that de novo variants were located at crucial domains, whereas one paired biallelic variants were located outside the crucial domains, and the other paired variant had a non-classical splicing and a variant located at crucial domain, suggesting a sub-molecular effect. CCDC88C variants associated with congenital hydrocephalus were all truncated, whereas epilepsy-associated variants were mainly missense, the proportion of which was significantly higher than that of congenital hydrocephalus-associated variants. CCDC88C is potentially associated with focal epilepsy with favorable outcome. The underlying mechanisms of phenotypic variation may correlation between genotype and phenotype.


Asunto(s)
Epilepsias Parciales , Epilepsia , Hidrocefalia , Lactante , Adulto , Humanos , Epilepsias Parciales/genética , Epilepsia/genética , Hidrocefalia/genética , Genotipo , Estudios de Asociación Genética , Proteínas de Microfilamentos/genética , Péptidos y Proteínas de Señalización Intracelular/genética
10.
Plants (Basel) ; 12(20)2023 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-37895998

RESUMEN

Eremosparton songoricum (Litv.) Vass. is a rare and extremely drought-tolerant legume shrub that is distributed in Central Asia. E. songoricum naturally grows on bare sand and can tolerate multiple extreme environmental conditions. It is a valuable and important plant resource for desertification prevention and environmental protection, as well as a good material for the exploration of stress tolerance mechanisms and excellent tolerant gene mining. However, the regeneration system for E. songoricum has not yet been established, which markedly limits the conservation and utilization of this endangered and valuable desert legume. Assimilated branches derived from seedlings were cultured on several MS mediums supplemented with various concentrations of TDZ or 6-BA in different combinations with NAA. The results showed that the most efficient multiplication medium was MS medium supplemented with 0.4 mg/L 6-BA and 0.1 mg/L NAA. The most efficient rooting medium was WPM + 25 g/L sucrose. The highest survival rate (77.8%) of transplantation was achieved when the ratio of sand to vermiculite was 1:1. In addition, the optimal callus induction medium was MS + 30 g/L sucrose + 2 mg/L TDZ + 0.5 mg/L NAA in darkness. The E. songoricum callus treated with 100 mM NaCl and 300 mM mannitol on MS medium could be used in proper salt and drought stress treatments in subsequent gene function tests. A rapid and efficient regeneration system for E. songoricum that allowed regeneration within 3 months was developed. The protocol will contribute to the conservation and utilization of this rare and endangered desert stress-tolerant species and also provide a fundamental basis for gene functional analysis in E. songoricum.

11.
Zhongguo Zhen Jiu ; 43(8): 921-4, 2023 Aug 12.
Artículo en Chino | MEDLINE | ID: mdl-37577889

RESUMEN

OBJECTIVE: To compare the clinical effect between heat-sensitive moxibustion and mild moxibustion for migraine without aura. METHODS: A total of 54 patients with migraine without aura were randomized into an observation group (27 cases, 2 cases dropped off) and a control group (27 cases, 2 cases dropped off). The basic western medication treatment was adopted in the two groups. In the control group, mild moxibustion was applied at Shuaigu (GB 8), Fengchi (GB 20) and Yanglingquan (GB 34) on the affected side. In the observation group, the frequent acupoint areas of the affected side i.e. Shuaigu (GB 8), Fengchi (GB 20), Taiyang (EX-HN 5), Taichong (LR 3), Yanglingquan (GB 34) were determined, 3 acupoints with strong heat-sensitive sensation were selected each time and mild moxibustion was adopted. The treatment was given once a day, 5 times of treatment was as one course and 2 courses were required in the two groups. Before and after treatment, the scores of migraine symptom, visual analogue scale (VAS), migraine specific quality of life questionnaire (MSQ) were observed, and the clinical efficacy was evaluated after treatment in the two groups. RESULTS: After treatment, the scores of migraine symptom and VAS were decreased compared with those before treatment (P<0.01), while the MSQ scores were increased compared with those before treatment (P<0.01) in the two groups. After treatment, the scores of migraine symptom and VAS in the observation group were lower than those in the control group (P<0.05), while the MSQ score in the observation group was higher than that in the control group (P<0.01). The total effective rate was 92.0% (23/25) in the observation group, which was superior to 72.0% (18/25) in the control group (P<0.05). CONCLUSION: Both heat-sensitive moxibustion and mild moxibustion can effectively alleviate the clinical symptoms, improve the headache degree and life quality in patients with migraine without aura, the clinical efficacy of heat-sensitive moxibustion is superior to that of mild moxibustion.


Asunto(s)
Terapia por Acupuntura , Migraña sin Aura , Moxibustión , Humanos , Migraña sin Aura/terapia , Calor , Calidad de Vida , Puntos de Acupuntura , Resultado del Tratamiento
12.
J Am Chem Soc ; 145(28): 15589-15599, 2023 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-37410888

RESUMEN

Deoxygenation of phosphine oxides is of great significance to synthesis of phosphorus ligands and relevant catalysts, as well as to the sustainability of phosphorus chemistry. However, the thermodynamic inertness of P═O bonds poses a severe challenge to their reduction. Previous approaches in this regard rely primarily on a type of P═O bond activation with either Lewis/Brønsted acids or stoichiometric halogenating reagents under harsh conditions. Here, we wish to report a novel catalytic strategy for facile and efficient deoxygenation of phosphine oxides via successive isodesmic reactions, whose thermodynamic driving force for breaking the strong P═O bond was compensated by a synchronous formation of another P═O bond. The reaction was enabled by PIII/P═O redox sequences with the cyclic organophosphorus catalyst and terminal reductant PhSiH3. This catalytic reaction avoids the use of the stoichiometric activator as in other cases and features a broad substrate scope, excellent reactivities, and mild reaction conditions. Preliminary thermodynamic and mechanistic investigations disclosed a dual synergistic role of the catalyst.

13.
Heliyon ; 9(7): e17983, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37496928

RESUMEN

Normal pregnancy is a hypercoagulable state with an increase in coagulation factor levels and a decrease in natural anticoagulation. However, a higher hypercoagulable state with prolonged activated partial thromboplastin time (APTT), prothrombin time (PT), increased D-dimer, and mean platelet volume is seen in women with preeclampsia at the time of onset. In addition, endothelial dysfunction occurs before the clinical symptoms of preeclampsia. Therefore, we undertook this study to investigate the coagulation profile in the first trimester in women who developed preeclampsia later. A total of 853 pregnant women with singleton births at the Obstetrics and Gynecology Hospital of Fudan University between January 2021 and December 2021 were included in this case-control study. In the comparison with the controls (n = 531), the mean value of D-dimer, APTT, thrombin time (TT), antithrombin (AT)), and fibrin degradation products (FDP) was significantly lower in preeclamptic women at the time of diagnosis (n = 322). The changes in the coagulation profile were not associated with the severity or the time of onset. The reduced values of D-dimer, AT, and FDP, and increased values of TT were also observed in the first trimester in women who developed preeclampsia later and were not associated with the severity, or the time of onset of preeclampsia. After adjusting for maternal age and BMI, the values of D-dimer and AT in the first trimester were correlated to the risk of developing preeclampsia. Our findings suggest that there is an abnormal maternal response to the hemostatic system in early gestational age in women who developed preeclampsia later and measuring the coagulation profile could be an additional predictive marker of preeclampsia.

14.
Chemphyschem ; 24(14): e202300162, 2023 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-37132072

RESUMEN

Nucleophilicity and electrophilicity dictate the reactivity of polar organic reactions. In the past decades, Mayr et al. established a quantitative scale for nucleophilicity (N) and electrophilicity (E), which proved to be a useful tool for the rationalization of chemical reactivity. In this study, a holistic prediction model was developed through a machine-learning approach. rSPOC, an ensemble molecular representation with structural, physicochemical and solvent features, was developed for this purpose. With 1115 nucleophiles, 285 electrophiles, and 22 solvents, the dataset is currently the largest one for reactivity prediction. The rSPOC model trained with the Extra Trees algorithm showed high accuracy in predicting Mayr's N and E parameters with R2 of 0.92 and 0.93, MAE of 1.45 and 1.45, respectively. Furthermore, the practical applications of the model, for instance, nucleophilicity prediction of NADH, NADPH and a series of enamines showed potential in predicting molecules with unknown reactivity within seconds. An online prediction platform (http://isyn.luoszgroup.com/) was constructed based on the current model, which is available free to the scientific community.

16.
Front Pharmacol ; 14: 1038906, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36909150

RESUMEN

Cardio-cerebrovascular diseases are the leading cause of death worldwide and there is currently no optimal treatment plan. Chinese herbal medicine injection (CHI) is obtained by combining traditional Chinese medicine (TCM) theory and modern production technology. It retains some characteristics of TCM while adding injection characteristics. CHI has played an important role in the treatment of critical diseases, especially cardio-cerebrovascular diseases, and has shown unique therapeutic advantages. TCMs that promote blood circulation and remove blood stasis, such as Salvia miltiorrhiza, Carthami flos, Panax notoginseng, and Chuanxiong rhizoma, account for a large proportion of CHIs of cardio-cerebrovascular disease. CHI is used to treat cardio-cerebrovascular diseases and has potential pharmacological activities such as anti-platelet aggregation, anti-inflammatory, anti-fibrosis, and anti-apoptosis. However, CHIs have changed the traditional method of administering TCMs, and the drugs directly enter the bloodstream, which may produce new pharmacological effects or adverse reactions. This article summarizes the clinical application, pharmacological effects, and mechanism of action of different varieties of CHIs commonly used in the treatment of cardio-cerebrovascular diseases, analyzes the causes of adverse reactions, and proposes suggestions for rational drug use and pharmaceutical care methods to provide a reference for the rational application of CHIs for cardio-cerebrovascular diseases.

17.
Small ; 19(16): e2205420, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36670081

RESUMEN

Climate change is causing droughts and water shortages. Membrane desalination is one of the most widely employed conventional methods of creating a source of clean water, but is a very energy-intensive process. Membrane separation requires high salt selectivity across nano-channels, yet traditional techniques remain inefficient in this regard. Herein, a bioinspired, chemically robust, amyloid-fibril-based nanotube is designed, exhibiting water permeability and salt rejection properties capable of providing highly efficient desalination. Molecular dynamics simulations show that nano-dewetting facilitates the unidirectional motion of water molecules on the surface of amyloid beta (Aß) sheets owing to the ratchet structure of the underlying potential surface and the broken detailed balance. The water inside the self-assembled Aß nanotube (ABNT) overflows, while the passage of salts can be blocked using amphiphilic peptides. The designed nanofilter ABNT shows 100% desalination efficiency with perfect NaCl rejection. The production of ≈2.5 tons of pure water per day without any energy input, which corresponds to a water flux up to 200 times higher than those of existing commercial methods, is assessed by this simulation method. These results provide a detailed fundamental understanding of potential high-performance nanotechnologies for water treatment.

18.
Pharmaceuticals (Basel) ; 16(1)2023 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-36678590

RESUMEN

Boron neutron capture therapy (BNCT) is a binary therapeutic technique employing a boron agent to be delivered to the tumor site followed by the irradiation of neutrons. Biofunctional molecules/nanoparticles labeled with F-18 can provide an initial pharmacokinetic profile of patients to guide the subsequent treatment planning procedure of BNCT. Borono phenylalanine (BPA), recognized by the l-type amino acid transporter, can cross the blood-brain barrier and be accumulated in gliomas. The radiofluoro BNCT agents are reviewed by considering (1) less cytotoxicity, (2) diagnosing and therapeutic purposes, (3) aqueous solubility and extraction route, as well as (4), the trifluoroborate effect. A trifluoroborate-containing amino acid such as fluoroboronotyrosine (FBY) represents an example with both functionalities of imaging and therapeutics. Comparing with the insignificant cytotoxicity of clinical BPA with IC50 > 500 µM, FBY also shows minute toxicity with IC50 > 500 µM. [18F]FBY is a potential diagnostic agent for its tumor to normal accumulation (T/N) ratio, which ranges from 2.3 to 24.5 from positron emission tomography, whereas the T/N ratio of FBPA is greater than 2.5. Additionally, in serving as a BNCT therapeutic agent, the boron concentration of FBY accumulated in gliomas remains uncertain. The solubility of 3-BPA is better than that of BPA, as evidenced by the cerebral dose of 3.4%ID/g vs. 2.2%ID/g, respectively. While the extraction route of d-BPA differs from that of BPA, an impressive T/N ratio of 6.9 vs. 1.5 is noted. [18F]FBPA, the most common clinical boron agent, facilitates the application of BPA in clinical BNCT. In addition to [18F]FBY, [18F] trifluoroborated nucleoside analog obtained through 1,3-dipolar cycloaddition shows marked tumoral uptake of 1.5%ID/g. Other examples using electrophilic and nucleophilic fluorination on the boron compounds are also reviewed, including diboronopinacolone phenylalanine and nonsteroidal anti-inflammatory agents.

19.
J Org Chem ; 88(1): 540-547, 2023 01 06.
Artículo en Inglés | MEDLINE | ID: mdl-36573883

RESUMEN

Hydroxylamines, represented by 1-hydroxy-2,2,6,6-tetramethylpiperidine (TEMPOH), are widely involved as active species in various chemical and electrochemical oxidations. The electrochemical behavior of TEMPOH is crucial to understanding the mechanisms of TEMPO-mediated redox sequences. However, compared to abundant studies on TEMPOH electrochemistry in aqueous solutions, the sole value of its oxidation potential Eox(TEMPOH) in organic solutions was reported to be 0.7 V (vs Fc in acetonitrile), seemingly conflicting with experimentally observed facile oxidation of TEMPOH. Herein, the electrochemistry of TEMPOH derivatives in acetonitrile was revisited, featuring much smaller oxidation potentials (about 0 V) than literature ones. Acid/base effects and kinetic studies lent credibility to these new values. Such a 0.7 V energy discrepancy impelled us to review the thermodynamic properties and oxidation mechanisms of TEMPOH deduced from the old value.


Asunto(s)
Agua , Electroquímica , Cinética , Oxidación-Reducción , Acetonitrilos/química
20.
China Tropical Medicine ; (12): 304-2023.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-979635

RESUMEN

@#Coronavirus disease 2019 (COVID-19) is a highly contagious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). More than one-third of patients with COVID-19 experience neurological symptoms, including confusion, headaches, and decreased/disordered taste. Alzheimer's disease (AD) is a slowly progressive neurodegenerative disease and the most common type of dementia. Alzheimer's disease patients are at high risk and susceptible to infection with COVID-19, which may cause severe illness and even death. There appears to be an interaction between AD and COVID-19, and on the one hand, patients with COVID-19 seem to be more likely to develop AD. AD patients, on the other hand, may be more susceptible to severe COVID-19. Therefore, understanding the common link between COVID-19 and AD may help to develop treatment strategies. Risk factors common to AD and COVID-19 are aging, ApoE ε4 allele, β-amyloid (Aβ) deposition, angiotensin-converting enzyme (ACE), neuroinflammation, oxidative stress. Here, this article focuses on the relationship between COVID-19 and AD, explores common risk factors and potential pathogenesis, and provides help for early prevention, treatment and recovery.

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