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1.
Mycopathologia ; 189(2): 20, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38407662

RESUMO

Candidal granuloma is an uncommon type of deep chronic cutaneous candidiasis. Candida albican is the most common causative pathogen for candidal granuloma. We report herein the original case of a 69-year-old Chinese woman presented with a 3-year of painful cutaneous lesion on the back of left hand. Physical examination revealed a 4 × 5 cm large infiltrative reddish plaque with unclear boundaries. The yellow-white crusts were observed on the uneven surface of plaque. Histopathological examination of biopsy tissue revealed that yeast cells and the horizontal section of hyphae in the dermis by hematoxylin eosin staining and periodic acid-Schiff staining. Finally, the pathogen was identified as Candida parapsilosis by mycological examination and molecular identification. The patient was treated with itraconazole oral 200 mg twice daily combined with topical terbinafine hydrochloride cream for 2 months. The lesions were fully resolved and no recurrence was observed. Since the cutaneous infection caused by C. parasilosis were rarely reported, we also reviewed all 11 cases of cutaneous infection caused by C. parapsilosis in the PubMed. Our study highlighted that chronic unilateral infiltrated plaques or ulcers should be aware of the occurrence of fungal granuloma including candidal granuloma especially in immunocompromised patients.


Assuntos
Candidíase Mucocutânea Crônica , Candidíase , Feminino , Humanos , Idoso , Candida parapsilosis , Granuloma/diagnóstico , Granuloma/tratamento farmacológico , Celulite (Flegmão) , Candida , Candidíase/diagnóstico , Candidíase/tratamento farmacológico
2.
Neurotoxicology ; 99: 24-33, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37717738

RESUMO

Methamphetamine (METH) has been established to selectively target and impair dopaminergic neurons through multiple pathways. Ferroptosis is a unique form of non-apoptotic cell death driven by cellular iron accumulation-induced lipid peroxidation. Nonetheless, it remains unclear whether METH can induce ferroptosis. In the present study, we sought to assess alterations in iron levels after chronic METH exposure and reveal the modulatory role of iron on METH-induced pathologies. Importantly, we demonstrated that METH increased iron deposition in the nigrostriatal system, including the substantia nigra (SN) and caudate putamen (CPu). Moreover, decreases in GPx4 levels, increases in lipid peroxidation products, and pathological alterations were observed in the nigrostriatal system as a consequence of chronic METH exposure. The iron chelator deferiprone not only alleviated nigrostriatal iron deposition, dopaminergic cell death, and lipid peroxidation, but alsoattenuated the decreases in GPx4 induced by METH. These findings suggest an alleviation of ferroptosis in dopaminergic neurons. In addition, we found that the ferroptosis inhibitor liproxstatin-1 attenuated METH-induced dopaminergic degeneration in the nigrostriatal system. Our findings corroborated that METH might induce dopaminergic neurodegeneration through iron-dependent ferroptosis. Interestingly, reducing iron levels or inhibiting ferroptosis may alleviate METH-induced dopaminergic neurodegeneration.


Assuntos
Metanfetamina , Camundongos , Animais , Metanfetamina/toxicidade , Dopamina/metabolismo , Encéfalo/metabolismo , Ferro/metabolismo , Quelantes de Ferro/farmacologia
3.
J Am Chem Soc ; 145(38): 20927-20935, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37710975

RESUMO

Thermosetting polymers possess excellent environmental resistance and mechanical properties but cannot be reprocessed due to their covalently cross-linked structures. Recycling of thermosets via the implantation of dynamic covalent bonds offers a promising solution. Here, we report the direct and catalyst-free ester metathesis of N-acyloxyphthalimide (NAPI) at about 100 °C without the requirement of hydroxyl groups and its utilization for the fabrication of covalent adaptable networks (CANs). NAPI metathesis has interesting sigmoid kinetics with a fast exchange rate, which proceeds via a free radical chain mechanism, guaranteeing a fast associative exchange under a rather low dissociation. The bifunctional molecule of NAPI as both the radical precursor and substrate is the key to the dissociatively initiated associative (DAssociative) mechanism and kinetic behavior. Based on the efficient NAPI metathesis, polyester networks, poly(N-acyloxyphthalimides) (PNAPIs), show excellent malleability. Notably, PNAPIs exhibit exceptional solvent resistance and mechanical stability at elevated temperatures owing to the unique DAssociative mechanism, suggesting exciting opportunities for designing recyclable thermosetting polymers.

4.
Biomed Res Int ; 2021: 5520053, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34337017

RESUMO

BACKGROUND: Treponema pallidum subspecies pallidum (T. pallidum) infection induces significant immune responses, resulting in tissue damage. Gene expression plays an essential role in regulating the progression of syphilis infection. However, little is known about the regulatory role of microRNAs (miRNAs) in the immune response to T. pallidum infection. Here, we analyze the differential expression of miRNAs in peripheral blood mononuclear cells (PBMCs) between untreated secondary syphilis patients and healthy controls and study the correlation between miRNA expression and clinical features with bioinformatics. METHODS: The expression profile of miRNAs was measured by microarray analysis in PBMCs of untreated secondary syphilis patients and healthy controls. Weighted Gene Coexpression Network Analysis (WGCNA) was used to construct the expression of miRNAs and the clinical data of secondary syphilis patients. Gene ontology (GO) and KEGG enrichment analyses were performed on target genes of miR-142-3p. RESULTS: 244 miRNAs exhibited at least 1.0-fold differential expression between secondary syphilis patients and healthy controls. The miRNAs were divided into three modules by WGCNA. The blue module was positively correlated with TPHA, TRUST, duration of disease, and erythema. And in the blue module, the expression of miR-142-3p was significantly higher in secondary syphilis patients than in healthy controls (p = 0.02), which is also close to the clinical features of secondary syphilis. GO and KEGG pathway analyses showed that these target genes of miR-142-3p are correlated with endocytosis and positive regulation of the apoptotic process. CONCLUSION: The elevated miR-142-3p expression in PBMCs may play an important role in the immune response to T. pallidum infection and may be a potential biomarker for secondary syphilis.


Assuntos
Regulação da Expressão Gênica , Genoma Humano , Leucócitos Mononucleares/metabolismo , MicroRNAs/genética , Sífilis/sangue , Sífilis/genética , Adolescente , Adulto , Biomarcadores/metabolismo , Estudos de Casos e Controles , Feminino , Perfilação da Expressão Gênica , Ontologia Genética , Humanos , Imunidade/genética , Masculino , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Fenótipo , Mapas de Interação de Proteínas/genética , Sífilis/imunologia , Adulto Jovem
5.
J Cosmet Dermatol ; 20(11): 3661-3665, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33630414

RESUMO

BACKGROUND: Sebum secretion is affected by many internal and external factors. OBJECTIVE: To identify risk factors in terms of family history, body mass index, selected dietary factors, personal habits, and menstrual history that may be associated with oily skin in young women. PARTICIPANTS AND METHODS: We conducted a case-control study of young women aged 18-35 who came to Beijing Tongren Hospital for attending a health checkup. Cases were subjects with subjective skin type as oily skin. Control subjects were people with normal or dry skin. A standardized questionnaire on subjective skin type, family history of oily skin in first-degree relatives, menstrual history, personal habits, and selected dietary factors was administered to 540 subjects. Univariate and multivariate logistic regression analyses were performed for risk factors associated with oily skin. RESULTS: A family history in first-degree relatives and a body mass index of more than 24 kg/m2 were risk factors that increases likelihood of oily skin in young women (odds ratio 3.281, 95% confidence interval 2.204-4.882; odds ratio 1.677, 95% confidence interval 1.081-2.600, respectively). For those who consumed more than three servings of milk or sweets per week, the risk increased with the diet (odds ratio 1.634, 95% confidence interval 1.126-2.370; odds ratio 1.970, 95% confidence interval 1.034-3.754, respectively). There was no correlation between smoking, drinking alcohol, or menstrual variables and the risk of oily skin. CONCLUSIONS: Family history, overweight and obesity, and a diet rich in milk or sweets are risk factors that increase likelihood of oily skin in young women. These findings may provide an opportunity to better guide skin care for patients.


Assuntos
Dieta , Obesidade , Índice de Massa Corporal , Estudos de Casos e Controles , Feminino , Hábitos , Humanos
6.
ACS Appl Mater Interfaces ; 13(3): 4499-4507, 2021 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-33433191

RESUMO

The construction of a single polymer network with extreme stretchability, relatively high mechanical strength, and fast and facile autonomous room-temperature self-healing capability still remains a challenge. Herein, supramolecular polymer networks are fabricated by synergistically incorporating metal-ligand and hydrogen bonds in poly(propylene glycol) (PPG). The representative specimen, PPG-Im-MDA-1.5-0.25-Cu, shows a combination of notable mechanical properties involving an extreme stretching ratio of 346 ± 14× and a Young's modulus of 2.10 ± 0.14 MPa, which are superior to the previously reported extremely stretchable polymeric materials. Notably, the destroyed specimen can fully recover mechanical performances within 1 h. The tunability of mechanical properties and self-healing capability has been actualized by merely tailoring the content of a chain extender. The application of the as-prepared supramolecular PPG network in constructing a flexible and self-healable conductor has been demonstrated. This strategy provides some insights for preparing extremely stretchable and self-healable polymeric materials.

7.
Nat Commun ; 10(1): 4753, 2019 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-31628332

RESUMO

Constructing responsive and adaptive materials by dynamic covalent bonds is an attractive strategy in material design. Here, we present a kind of dynamic covalent polyureas which can be prepared from the highly efficient polyaddition reaction of pyrazoles and diisocyanates at ambient temperature in the absence of a catalyst. Owing to multiphase structural design, poly(pyrazole-ureas) (PPzUs) show excellent mechanical properties and unique crystallization behavior. Besides, the crosslinked PPzUs can be successfully recycled upon heating (~130 °C) and the molecular-level blending of polyurea and polyurethane is realized. Theoretical studies prove that the reversibility of pyrazole-urea bonds (PzUBs) arises from the unique aromatic nature of pyrazole and the N-assisting intramolecular hydrogen transfer process. The PzUBs could further broaden the scope of dynamic covalent bonds and are very promising in the fields of dynamic materials.

8.
ACS Appl Mater Interfaces ; 11(17): 15945-15951, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30942081

RESUMO

Super black materials with extremely low reflectance and high absorption of incident light are crucial in various applications with strict optical requirements. However, the existing super black materials suffer from technical complexity in practical use whereas the underlying physics of their ultralow reflectance is still unclear. Herein, hierarchical porous carbon spheres are prepared using poly(vinylidene chloride- co-vinyl chloride) as a precursor. Dehydrochlorination treatment has proved to be very crucial for the morphology robustness of the porous polymer spheres during carbonization process. Coatings cast from the dispersion of these carbon spheres exhibit a hemispherical reflectance of <0.2% in the visible region and <0.3% in the range of 300-2000 nm, and the lowest reflectance of 0.14% can be reached. This super black coating has great advantages in its easy availability of starting materials, low equipment requirement, and high adaptability onto various substrates. Besides, a theoretical investigation suggests that a small scatterer size and low volume-filling ratio are the two most essential factors in realizing ultralow reflectance, which also offers an instructive guidance for the rational design of super black materials.

9.
Org Lett ; 19(6): 1458-1461, 2017 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-28263076

RESUMO

The first asymmetric hydrogenation of phenanthridines catalyzed by chiral cationic ruthenium diamine complexes has been developed with up to 92% ee and full conversions. The choice of the counteranion of the catalyst was found to be critical for achieving high enantioselectivity. In addition, the obtained 5,6-dihydrophenanthridine could be used as a chiral hydride donor for organocatalytic asymmetric transfer hydrogenation.

10.
Angew Chem Int Ed Engl ; 55(44): 13863-13866, 2016 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-27689778

RESUMO

A highly enantioselective synthesis of indolines by asymmetric hydrogenation of 1H-indoles and 3H-indoles at ambient temperature and pressure, catalyzed by chiral phosphine-free cationic ruthenium complexes, has been developed. Excellent enantio- and diastereoselectivities (up to >99 % ee, >20:1 d.r.) were obtained for a wide range of indole derivatives, including unprotected 2-substituted and 2,3-disubstituted 1H-indoles, as well as 2-alkyl- and 2-aryl-substituted 3H-indoles.

11.
Chirality ; 27(7): 422-4, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25975180

RESUMO

The application of helical poly[(S)-3-vinyl-2,2'-dihydroxy-1, 1'-binaphthyl] (L*) in the asymmetric borane reduction of prochiral ketones was studied. The results showed that L* had excellent catalytic activity as well as enantioselectivity, giving up to 96% yield and up to 99% enantiomeric excess (ee) of the corresponding secondary alcohol at 25 °C. Moreover, L* can be easily recovered and reused without loss of catalytic activity.

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