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1.
ACS Nano ; 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38771969

RESUMO

Hydrogen obtained from electrochemical water splitting is the most promising clean energy carrier, which is hindered by the sluggish kinetics of the oxygen evolution reaction (OER). Thus, the development of an efficient OER electrocatalyst using nonprecious 3d transition elements is desirable. Multielement synergistic effect and lattice oxygen oxidation are two well-known mechanisms to enhance the OER activity of catalysts. The latter is generally related to the high valence state of 3d transition elements leading to structural destabilization under the OER condition. We have found that Al doping in nanosheet Ni-Fe hydroxide exhibits 2-fold advantage: (1) a strong enhanced OER activity from 277 mV to 238 mV at 10 mA cm-2 as the Ni valence state increases from Ni3.58+ to Ni3.79+ observed from in situ X-ray absorption spectra. (2) Operational stability is strengthened, while weakness is expected since the increased NiIV content with 3d8L2 (L denotes O 2p hole) would lead to structural instability. This contradiction is attributed to a reduced lattice oxygen contribution to the OER upon Al doping, as verified through in situ Raman spectroscopy, while the enhanced OER activity is interpreted as an enormous gain in exchange energy of FeIV-NiIV, facilitated by their intersite hopping. This study reveals a mechanism of Fe-Ni synergy effect to enhance OER activity and simultaneously to strengthen operational stability by suppressing the contribution of lattice oxygen.

2.
J Int Med Res ; 52(5): 3000605241253454, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38759213

RESUMO

OBJECTIVE: To explore the prevalence of type I and type II Helicobacter pylori infection and investigate risk factors in a population from Hainan Province in China. METHODS: Data came from a large, cross-sectional study conducted from August 2022 to April 2023 involving five cities of Hainan. Subjects with confirmed 14C-urea breath test (UBT) and positive serological assay were included. All subjects had a gastroscopy. According to presence or absence of CagA/VacA proteins, subjects were classified as either type I (present) or type II strains (absent). Gastroscopic findings and several socio-demographic factors were examined for correlation with antibody serotyping. RESULTS: In total, 410 subjects were investigated for H. pylori strain types. The overall prevalence of the highly virulent, type I H. pylori strain was 79% (324/410) and type II strain was 21% (86/410). There was a strong association between type I strain and peptic ulcer disease. Of several sociodemographic factors investigated, only smoking and data over baseline (DOB) values showed significant differences between type 1 and type II strains. Logistic regression analysis showed a lower risk of type I H. pylori infection in smokers compared with non-smokers, and a higher risk of H. pylori type I infection in subjects with medium and high data over baseline (DOB) values compared with subjects who had low DOB values. CONCLUSION: Highly virulent, type I H. pylori infections predominate in Hainan and the co-positivity of CagA and VacA antibodies are related to type I H. pylori infection. We found that Type I H. pylori was closely associated with peptic ulcer disease and the DOB values were generally high.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Humanos , Helicobacter pylori/isolamento & purificação , Helicobacter pylori/imunologia , Helicobacter pylori/patogenicidade , Masculino , Feminino , China/epidemiologia , Infecções por Helicobacter/microbiologia , Infecções por Helicobacter/epidemiologia , Infecções por Helicobacter/diagnóstico , Pessoa de Meia-Idade , Fatores de Risco , Estudos Transversais , Adulto , Proteínas de Bactérias , Prevalência , Antígenos de Bactérias/imunologia , Úlcera Péptica/microbiologia , Úlcera Péptica/epidemiologia , Idoso , Testes Respiratórios , Anticorpos Antibacterianos/sangue , Anticorpos Antibacterianos/imunologia
3.
Environ Sci Ecotechnol ; 21: 100411, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38746776

RESUMO

Recent advancements in constructed wetlands (CWs) have highlighted the imperative of enhancing nitrogen (N) removal efficiency. However, the variability in influent substrate concentrations presents a challenge in optimizing N removal strategies due to its impact on removal efficiency and mechanisms. Here we show the interplay between influent substrate concentration and N removal processes within integrated vertical-flow constructed wetlands (IVFCWs), using wastewaters enriched with NO3--N and NH4+-N at varying carbon to nitrogen (C/N) ratios (1, 3, and 6). In the NO3--N enriched systems, a positive correlation was observed between the C/N ratio and total nitrogen (TN) removal efficiency, which markedly increased from 13.46 ± 2.23% to 87.00 ± 2.37% as the C/N ratio escalated from 1 to 6. Conversely, in NH4+-N enriched systems, TN removal efficiencies in the A-6 setup (33.69 ± 4.83%) were marginally 1.25 to 1.29 times higher than those in A-3 and A-1 systems, attributed to constraints in dissolved oxygen (DO) levels and alkalinity. Microbial community analysis and metabolic pathway assessment revealed that anaerobic denitrification, microbial N assimilation, and dissimilatory nitrate reduction to ammonium (DNRA) predominated in NO3--N systems with higher C/N ratios (C/N ≥ 3). In contrast, aerobic denitrification and microbial N assimilation were the primary pathways in NH4+-N systems and low C/N NO3--N systems. A mass balance approach indicated denitrification and microbial N assimilation contributed 4.12-47.12% and 8.51-38.96% in NO3--N systems, respectively, and 0.55-17.35% and 7.83-33.55% in NH4+-N systems to TN removal. To enhance N removal, strategies for NO3--N dominated systems should address carbon source limitations and electron competition between denitrification and DNRA processes, while NH4+-N dominated systems require optimization of carbon utilization pathways, and ensuring adequate DO and alkalinity supply.

4.
Cancer Res ; 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38748783

RESUMO

Triple-negative breast cancer (TNBC) is the most aggressive subtype of breast cancer. Transcriptional dysregulation is a hallmark of cancer, and several transcriptional regulators have been demonstrated to contribute to cancer progression. Here, we identified upregulation of the transcriptional corepressor DRAP1 in TNBC, which was closely associated with poor recurrence-free survival in TNBC patients. DRAP1 promoted TNBC proliferation, migration, and invasion in vitro and tumor growth and metastasis in vivo. Mechanistically, the DR1/DRAP1 heterodimer complex inhibited expression of the arginine sensor CASTOR1 and thereby increased activation of mTOR, which sensitized TNBC to treatment with the mTOR inhibitor everolimus. DRAP1 and DR1 also formed a positive feedback loop. DRAP1 enhanced the stability of DR1, recruiting the deubiquitinase USP7 to inhibit its proteasomal degradation; in turn, DR1 directly promoted DRAP1 transcription. Collectively, this study uncovered a DRAP1-DR1 bidirectional regulatory pathway that promotes TNBC progression, suggesting that targeting the DRAP1/DR1 complex might be a potential therapeutic strategy to treat TNBC.

5.
Biosens Bioelectron ; 259: 116385, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38759310

RESUMO

Cell-substrate interaction plays a critical role in determining the mechanical status of living cell membrane. Changes of substrate surface properties can significantly alter the cell mechanical microenvironment, leading to mechanical changes of cell membrane. However, it is still difficult to accurately quantify the influence of the substrate surface properties on the mechanical status of living cell membrane without damage. This study addresses the challenge by using an electrochemical sensor made from an ultrasmall quartz nanopipette. With the tip diameter less than 100 nm, the nanopipette-based sensor achieves highly sensitive, noninvasive and label-free monitoring of the mechanical status of single living cells by collecting stable cyclic membrane oscillatory signals from continuous current versus time traces. The electrochemical signals collected from PC12 cells cultured on three different substrates (bare ITO (indium tin oxides) glass, hydroxyl modified ITO glass, amino modified ITO glass) indicate that the microenvironment more favorable for cell adhesion can increase the membrane stiffness. This work provides a label-free electrochemical approach to accurately quantify the mechanical status of single living cells in real-time, which may help to better understand the relationship between the cell membrane and the extra cellular matrix.

6.
Food Res Int ; 183: 114199, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38760132

RESUMO

In this study, we conducted an analysis of the differences in nutrient composition and protein structure among various fermented soybean products and their impacts on the gut microbiota of rats. Conventional physicochemical analysis was employed to analyze the fundamental physicochemical composition of the samples. Additionally, we utilized high-performance liquid chromatography and ELISA techniques to quantify the presence of antinutritional compounds. Fourier infrared spectroscopy was applied to delineate the protein structure, while 16 s rRNA gene sequencing was conducted to evaluate alterations in gut microbiota abundance. Subsequently, KEGG was utilized for metabolic pathway analysis. Our findings revealed that fermented soybean products improved the nutritional profile of soybeans. Notably, Douchi exhibited the highest protein content at 52.18 g/100 g, denoting a 26.58 % increase, whereas natto showed a 24.98 % increase. Douchi and natto demonstrated the most substantial relative amino acid content, comprising 50.86 % and 49.04 % of the total samples, respectively. Moreover, the levels of antinutritional factors markedly decreased post-fermentation. Specifically, the α-helix content in doujiang decreased by 13.87 %, while the random coil content in soybean yogurt surged by 132.39 %. Rats that were fed FSP showcased notable enhancements in gut microbiota and associated metabolic pathways. A strong correlation was observed between nutrient composition, protein structure, and gut microbiota abundance. This study furnishes empirical evidence supporting the heightened nutritional attributes of FSPs.


Assuntos
Fermentação , Microbioma Gastrointestinal , Glycine max , Valor Nutritivo , Animais , Glycine max/química , Ratos , Masculino , Ratos Sprague-Dawley , Alimentos Fermentados/microbiologia , Proteínas de Soja , Alimentos de Soja/análise , Alimentos de Soja/microbiologia , Aminoácidos/análise
7.
J Dig Dis ; 25(3): 191-199, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38697920

RESUMO

OBJECTIVE: To compare the detection rate and diagnostic accuracy of cardia polyps using endoscopy with blue laser imaging (BLI) and white-light imaging (WLI). METHODS: Patients were randomly divided into the BLI group and WLI group according to the endoscopic procedures. BLI followed by WLI was conducted in the BLI group, whereas WLI followed by BLI examination was conducted in the WLI group. The number, size, microstructure, and microvascular patterns of cardia polyps detected were recorded. Biopsy of the polyps was then performed. RESULTS: The detection rate of cardia polyps in the BLI group was higher than that in the WLI group (7.87% vs 4.22%, P = 0.018). The rate of overlooked lesions in the BLI group was lower than in the WLI group (0.64% vs 3.38%, P = 0.003). The diagnostic coincidence rate between magnifying BLI and histopathology was 88.16%. The sensitivity, specificity, positive predictive value and negative predictive value for the diagnosis of neoplastic lesions by magnifying endoscopy with BLI were 90.91%, 87.69%, 55.56%, and 98.28%, respectively. The most remarkable patterns for predicting inflammatory polyps were the prolonged and fine network patterns (sensitivity 71.43%, specificity 93.75%). Small round combined with honeycomb patterns were the most common among fundic gland polyps (sensitivity 80.00%, specificity 98.48%). Neoplastic lesions presented as villous or ridge-like combined with core vascular or unclear pattern for both microvascular and microstructure patterns. CONCLUSION: BLI is more effective than WLI in the detection and diagnosis of cardia polyps, and magnifying endoscopy with BLI may help diagnose such lesions.


Assuntos
Cárdia , Estudos de Viabilidade , Neoplasias Gástricas , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Cárdia/patologia , Cárdia/diagnóstico por imagem , Adulto , Neoplasias Gástricas/diagnóstico por imagem , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/patologia , Idoso , Pólipos/diagnóstico por imagem , Pólipos/diagnóstico , Gastroscopia/métodos , Sensibilidade e Especificidade , Valor Preditivo dos Testes , Lasers
8.
Nat Commun ; 15(1): 3976, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38729948

RESUMO

Bleeding and thrombosis are known as common complications of polycythemia for a long time. However, the role of coagulation system in erythropoiesis is unclear. Here, we discover that an anticoagulant protein tissue factor pathway inhibitor (TFPI) plays an essential role in erythropoiesis via the control of heme biosynthesis in central macrophages. TFPI levels are elevated in erythroblasts of human erythroblastic islands with JAK2V617F mutation and hypoxia condition. Erythroid lineage-specific knockout TFPI results in impaired erythropoiesis through decreasing ferrochelatase expression and heme biosynthesis in central macrophages. Mechanistically, the TFPI interacts with thrombomodulin to promote the downstream ERK1/2-GATA1 signaling pathway to induce heme biosynthesis in central macrophages. Furthermore, TFPI blockade impairs human erythropoiesis in vitro, and normalizes the erythroid compartment in mice with polycythemia. These results show that erythroblast-derived TFPI plays an important role in the regulation of erythropoiesis and reveal an interplay between erythroblasts and central macrophages.


Assuntos
Eritroblastos , Eritropoese , Fator de Transcrição GATA1 , Heme , Lipoproteínas , Macrófagos , Policitemia , Policitemia/metabolismo , Policitemia/genética , Policitemia/patologia , Eritroblastos/metabolismo , Heme/metabolismo , Humanos , Animais , Lipoproteínas/metabolismo , Macrófagos/metabolismo , Camundongos , Fator de Transcrição GATA1/metabolismo , Fator de Transcrição GATA1/genética , Janus Quinase 2/metabolismo , Janus Quinase 2/genética , Trombomodulina/metabolismo , Trombomodulina/genética , Camundongos Knockout , Ferroquelatase/metabolismo , Ferroquelatase/genética , Masculino , Sistema de Sinalização das MAP Quinases , Camundongos Endogâmicos C57BL , Feminino
9.
J Microbiol Biotechnol ; 34(6): 1-12, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38783703

RESUMO

Ulcerative colitis (UC) is an inflammatory bowel disease (IBD) that is currently difficult to treat effectively. Both Bacillus natto (BN) and ginseng-soluble dietary fiber (GSDF) are anti-inflammatory and helps sustain the intestinal barrier. In this study, the protective effects and mechanism of the combination of B. natto JLCC513 and ginseng-soluble dietary fiber (BG) in DSS-induced UC mice were investigated. Intervention with BG worked better than taking BN or GSDF separately, as evidenced by improved disease activity index, colon length, and colon injury and significantly reduced the levels of oxidative and inflammatory factors (LPS, ILs, and TNF-α) in UC mice. Further mechanistic study revealed that BG protected the intestinal barrier integrity by maintaining the tight junction proteins (Occludin and Claudin1) and inhibited the LPS/TLR4/NF-κB pathway in UC mice. In addition, BG increased the abundance of beneficial bacteria such as Bacteroides and Turicibacter and reduced the abundance of harmful bacteria such as Allobaculum in the gut microbiota of UC mice. BG also significantly upregulated genes related to linoleic acid metabolism in the gut microbiota. These BGinduced changes in the gut microbiota of mice with UC were significantly correlated with changes in pathological indices. In conclusion, this study demonstrated that BG exerts protective effect against UC by regulating the LPS/TLR4/NF-κB pathway and the structure and metabolic function of gut microbiota. Thus, BG can be potentially used in intestinal health foods to treat UC.

10.
Opt Lett ; 49(9): 2297-2300, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38691703

RESUMO

We present a differential compressive imaging method for an optical fiber bundle (OFB), which provides a solution for an ultrathin bend-resistant endoscope with high resolution. This method uses an OFB and a diffuser to generate speckle illumination patterns. Differential operation is additionally applied to the speckle patterns to produce sensing matrices, by which the correlation between the matrices is greatly reduced from 0.875 to 0.0275, which ensures the high quality of image reconstruction. Pixilation artifacts from the fiber core arrangement are also effectively eliminated with this configuration. We demonstrate high-resolution reconstruction of images of 132 × 132 pixels with a compression rate of 12% using 77 fiber cores, the total diameter of which is only about 91 µm. An experimental verification proves that this method is tolerant to a limited degree of fiber bending, which provides a potential approach for robust high-resolution fiber endoscopy.

11.
Sci Adv ; 10(14): eadj4009, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38569025

RESUMO

Triple-negative breast cancer (TNBC) is the deadliest subtype of breast cancer owing to the lack of effective therapeutic targets. Splicing factor 3a subunit 2 (SF3A2), a poorly defined splicing factor, was notably elevated in TNBC tissues and promoted TNBC progression, as confirmed by cell proliferation, colony formation, transwell migration, and invasion assays. Mechanistic investigations revealed that E3 ubiquitin-protein ligase UBR5 promoted the ubiquitination-dependent degradation of SF3A2, which in turn regulated UBR5, thus forming a feedback loop to balance these two oncoproteins. Moreover, SF3A2 accelerated TNBC progression by, at least in part, specifically regulating the alternative splicing of makorin ring finger protein 1 (MKRN1) and promoting the expression of the dominant and oncogenic isoform, MKRN1-T1. Furthermore, SF3A2 participated in the regulation of both extrinsic and intrinsic apoptosis, leading to cisplatin resistance in TNBC cells. Collectively, these findings reveal a previously unknown role of SF3A2 in TNBC progression and cisplatin resistance, highlighting SF3A2 as a potential therapeutic target for patients with TNBC.


Assuntos
Cisplatino , Neoplasias de Mama Triplo Negativas , Humanos , Cisplatino/farmacologia , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/metabolismo , Processamento Alternativo , Linhagem Celular Tumoral , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Fatores de Processamento de RNA/genética , Fatores de Processamento de RNA/metabolismo
13.
J Asian Nat Prod Res ; : 1-17, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38572941

RESUMO

In recent years, with sinomenine hydrochloride as the main ingredient, Qingfengteng had been formulated as various dosage forms for clinical treatment. Subsequent findings confirmed a variety of biological roles for sinomenine. Here, 15 H2S-donating sinomenine derivatives were synthesized. Target hybrids a11 displayed substantial cytotoxic effects on cancer cell lines, particularly against K562 cells, with an IC50 value of 1.36 µM. In-depth studies demonstrated that a11 arrested cell cycle at G1 phase, induced apoptosis via both morphological changes in nucleus and membrane potential collapse in mitochondria. These results indicated a11 exerted an antiproliferative effect through apoptosis induction via mitochondrial pathway.

15.
Glob Med Genet ; 11(2): 142-149, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38606422

RESUMO

Objectives This study aimed to identify the association between lactate dehydrogenase (LDH) levels and 30-day mortality in patients with intracranial hemorrhage (ICH) with acute leukemia during the induction phase. Methods This cohort study included patients with acute leukemia with ICH during induction. We evaluated serum LDH levels upon admission. Multivariable Cox regression analyzed the LDH 30-day mortality association. Interaction and stratified analyses based on factors like age, sex, albumin, white blood cell count, hemoglobin level, and platelet count were conducted. Results We selected 91 patients diagnosed with acute leukemia and ICH. The overall 30-day mortality rate was 61.5%, with 56 of the 91 patients succumbing. Among those with LDH levels ≥ 570 U/L, the mortality rate was 74.4% (32 out of 43), which was higher than the 50% mortality rate of the LDH < 570 U/L group (24 out of 48) ( p = 0.017). In our multivariate regression models, the hazard ratios and their corresponding 95% confidence intervals for Log2 and twice the upper limit of normal LDH were 1.27 (1.01, 1.58) and 2.2 (1.05, 4.58), respectively. Interaction analysis revealed no significant interactive effect on the relationship between LDH levels and 30-day mortality. Conclusions Serum LDH level was associated with 30-day mortality, especially in patients with LDH ≥ 570 U/L.

16.
Sci Rep ; 14(1): 9034, 2024 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-38641639

RESUMO

To explore the knowledge, attitude, and practice (KAP) towards enhanced recovery after surgery (ERAS) among colorectal cancer (CRC) patients. This cross-sectional study included CRC patients who underwent selective operation at the author's Hospital, between April 2021 and April 2023. Their demographic characteristics and KAP towards ERAS were collected using a self-designed questionnaire. A total of 652 valid questionnaires were collected, with knowledge, attitude, and practice scores of 37.29 ± 11.35 (possible range: 11-55), 39.51 ± 6.40 (possible range: 11-55), and 6.53 ± 2.21 (possible range: 0-8), respectively. A positive correlation was found between knowledge and attitude (r = 0.291, P < 0.001), knowledge and practice (r = 0.292, P < 0.001), and attitude and practice (r = 0.363, P < 0.001). Structural equation model (SEM) analysis showed that knowledge had a significant direct effect on attitude (ß = 0.164, P < 0.001) and attitude had direct effect on practice (ß = 0.099, P < 0.001), indicating an indirect effect of knowledge on practice. Attitude also had a direct effect on practice (ß = 0.038, P < 0.001). CRC patients showed moderate knowledge and attitude, and proactive practice towards ERAS. Further improvement of knowledge may improve their attitude and practice, leading to better outcomes and quality of care among CRC patients.


Assuntos
Neoplasias Colorretais , Recuperação Pós-Cirúrgica Melhorada , Humanos , Estudos Transversais , Conhecimentos, Atitudes e Prática em Saúde , Inquéritos e Questionários , Neoplasias Colorretais/cirurgia
17.
J Hazard Mater ; 470: 134259, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38626687

RESUMO

Seeking for a safe, efficient, inexpensive, and eco-friendly oxidizer is always a big challenge for in-situ chemical oxidation (ISCO) technology. This study adopted the potassium peroxoborate (PPB), a novel peroxide, for soil remediation for the first time. PPB based chemical oxidation system (PPB-CO) could efficiently degrade polycyclic aromatic hydrocarbons (PAHs) without other reagents added, reaching 72.1 %, 64.2 %, and 50.0 % removal rates for naphthalene, phenanthrene, and pyrene after 24 h reaction, respectively. The superior total PAHs removal efficiency (60.6 %) was 3.6-4.7 times higher than that of other commercial peroxides (2Na2CO3•3H2O, CaO2, and H2O2). Mechanism analysis revealed that varieties of reactive oxygen species (ROS) can be generated by PPB through Fenton-like or non-Fenton routines, including H2O2, perborates species, O2•-, •OH, and 1O2. The sustainable generation of H2O2 reduced the disproportionation effect of H2O2 by 86 %, significantly improving the utilization rate. Moreover, sandbox experiments and actual contaminated soil remediation experiments verified the feasibility of PPB-CO in a real polluted site. This work provides a novel strategy for effectively soil remediation, highlighting the selection and application of new oxidants.

18.
Mater Today Bio ; 26: 101045, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38600921

RESUMO

The endometrium undergoes a series of precise monthly changes under the regulation of dynamic levels of ovarian hormones that are characterized by repeated shedding and subsequent regeneration without scarring. This provides the potential for wound healing during endometrial injuries. Bioengineering materials highlight the faithful replication of constitutive cells and the extracellular matrix that simulates the physical and biomechanical properties of the endometrium to a larger extent. Significant progress has been made in this field, and functional endometrial tissue bioengineering allows an in-depth investigation of regulatory factors for endometrial and myometrial defects in vitro and provides highly therapeutic methods to alleviate obstetric and gynecological complications. However, much remains to be learned about the latest progress in the application of bioengineering technologies to the human endometrium. Here, we summarize the existing developments in biomaterials and bioengineering models for endometrial regeneration and improving the female reproductive potential.

19.
Front Neurol ; 15: 1358881, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38651106

RESUMO

Background: There is growing evidence that severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) or COVID-19 infection is associated with the development of immune mediated neuropathies like chronic inflammatory demyelinating polyneuropathy (CIDP), but the impact of SARS-CoV-2 vaccination and COVID-19 infection on genetic disorders such as Charcot-MarieTooth (CMT) remains unclear. Case presentation: A 42-year-old male with occulted CMT neuropathy type lA (CMT1A) who developed limb numbness and weakness after the second SARS-CoV-2-vaccination was confirmed by identifying characteristic repeats in the p11.2 region of chromosome 17. Due to the progressive deterioration of muscle strength over 8 weeks, limb atrophy, moderately elevated protein counts in the cerebrospinal fluid, and significant improvement with intravenous human immunoglobulin, which were characteristic of acquired inflammatory neuropathies, he was eventually diagnosed with CIDP superimposed on CMT1A. However, after a three-month plateau, the patient contracted COVID-19, which led to repeated and worsening symptoms of limb weakness and atrophy, thus was diagnosed with a recurrence of CIDP and treated with Intravenous immunoglobulin and methylprednisolone 500 mg/d for 5 consecutive days, followed by oral prednisone and mycophenolate mofetil tablets. On 2 month follow-up, he exhibited remarkable clinical improvement and could walk independently with rocking gait. After 1 year of follow-up, the patient's condition was stable without further change. Conclusion: Our case indicates that CMT1A can deteriorate after SARS-CoV-2 vaccination. Thus, SARS-CoV-2 vaccination should be considered a potential predisposing factor for CMT1A worsening. The possible superposition of CMTIA and CIDP in the context of SARS-CoV-2 infection or immunity suggests that any clinical exacerbation in patients with CMT1A should be carefully evaluated to rule out treatable superposition inflammation. In addition, electrophysiological and imaging examination of the proximal nerves, such as the axillary nerve, is helpful for the diagnosis of CIDP.

20.
Chemistry ; : e202401014, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38570881

RESUMO

Highly regioselective C-H alkylation reactions of tertiary anilines and tertiary alkyl amines with simple alkenes have been achieved by the use of imidazolin-2-iminato scandium alkyl complexes. This protocol provided an efficient and atom-economical route to structurally diverse tertiary amine derivatives. The basic ligand, a coordinating THF in the catalyst and the substitution of alkene substrates were found to switch the regioselectivity of the C-H alkylation reactions of tertiary anilines presumably due to the generation of different types of catalytically active species or the formation of relatively stable intermediates. On the basis of the deuterium labeling experiments and KIE experiments, possible catalytical cycles were provided to understand the reaction mechanism as well as the regioselectivity.

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