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1.
Anticancer Drugs ; 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38742728

RESUMEN

Chemotherapy remains the main approach conserving vision during the treatment of retinoblastoma, the most prevalent eye cancer in children. Unfortunately, the development of chemoresistance stands as the primary reason for treatment failure. Within this study, we showed that prolonged exposure to vincristine led to heightened expression of JAK1 and JAK2 in retinoblastoma cells, while the other members of the JAK family exhibited no such changes. Employing a genetic intervention, we demonstrated the efficacy of depleting either JAK1 or JAK2 in countering vincristine-resistant retinoblastoma cells. In addition, the dual depletion of both JAK1 and JAK2 produced a more potent inhibitory outcome compared to the depletion of either gene alone. We further demonstrated that ruxolitinib, a small molecular inhibitor of JAK1/2, effectively reduced viability and colony formation in vincristine-resistant retinoblastoma cells. It also acts synergistically with vincristine in retinoblastoma cells regardless of inherent cellular and genetic heterogeneity. The effectiveness of ruxolitinib as standalone treatment against chemoresistant retinoblastoma, as well as its combination with vincristine, was validated in multiple retinoblastoma mouse models. Importantly, mice exhibited favorable tolerance to ruxolitinib administration. We confirmed that the underlying mechanism of ruxolitinib's action in chemoresistant retinoblastoma cells is the inhibition of Janus kinase/signal transducer and activator of transcription (JAK/STAT) signaling. Our study reveals that the underlying mechanism driving ruxolitinib's impact on chemoresistant retinoblastoma cells is the inhibition of JAK/STAT signaling. This study reveals the contribution of JAK1/2 to the development of chemoresistance in retinoblastoma and underscores the effectiveness of targeting JAK1/2 as a strategy to sensitize retinoblastoma to chemotherapy.

2.
Int J Ophthalmol ; 17(1): 164-172, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38239951

RESUMEN

AIM: To evaluate lacrimal gland adenoid cystic carcinoma (LGACC) of prognosis in patients who underwent different treatment regimens. METHODS: We searched PubMed, EMBASE, and the Cochrane Library for studies done on the treatment of LGACC, between January 1987 and April 2022. A Meta-analysis was conducted to pool the 5-year overall survival rate (OR), and the 5-year recurrence rate (RR) and 5-year metastasis rate (MR) were assessed. RESULTS: The 30 studies involved 585 patients were included in the Meta-analysis. The pooled 5-year OR with surgery alone was 50%, the 5-year RR was 63%, and the 5-year MR was 34%. The pooled 5-year OR with surgery and adjuvant radiotherapy combined was 67% (95%CI 61%,73%), the 5-year RR was 41%, and the 5-year MR was 35%. The pooled 5-year OR with surgery and adjuvant chemoradiotherapy combined was 72% (95%CI 59%, 84%), the 5-year RR was 48%, and the 5-year MR was 36%. The pooled 5-year OR with surgery, intra-arterial cytoreductive chemotherapy, and adjuvant chemoradiotherapy combined was 78% (95%CI 68%, 89%), the 5-year RR was 15%, and the 5-year MR was 27%. CONCLUSION: Comprehensive treatment is more effective than surgery alone. Surgery combined with intra-arterial chemotherapy and adjuvant chemoradiotherapy seems to add value to the therapeutic effect of comprehensive treatment of LGACC but further high-quality research is required to validate this.

3.
Inorg Chem ; 62(21): 8052-8057, 2023 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-37184543

RESUMEN

While a ligand-to-ligand charge-transfer (LLCT) process is an important way to understand the interactions between metal-bridged radicals for late-transition-metal complexes, there is little clear and evident observation of the LLCT process for rare-earth-metal complexes. In this work, rare-earth-metal diradical complexes supported by diazabutadiene (DAD) ligands [(DAD)2RE(BH4)] [RE = Yb (1), Sm (2)] were synthesized and studied. The coordination geometries of 1 and 2 are different due to the different ionic radii. Reduction of 1 or 2 generated monoradical complexes, with one of their DAD radical anions being reduced. In all of the complexes, Sm and Yb remain at the 3+ valence state. In their UV-vis spectra, the LLCT transition of 1 could be clearly observed, but complex 2 did not show the same transition. These results could be related to the geometric structures of the complexes as well as exchange coupling between diradicals, thus clearly expanding the model for late-transition-metal-bridged diradicals to rare-earth systems experimentally.

4.
J Neurol Neurosurg Psychiatry ; 93(3): 291-297, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34667102

RESUMEN

OBJECTIVE: Elucidate the core clinical and genetic characteristics and identify the phenotypic variation between different regions and genotypes of fatal familial insomnia (FFI). METHODS: A worldwide large sample of FFI patients from our case series and literature review diagnosed by genetic testing were collected. The prevalence of clinical symptoms and genetic profile were obtained, and then the phenotypic comparison between Asians versus non-Asians and 129Met/Met versus 129Met/Val were conducted. RESULTS: In total, 131 cases were identified. The age of onset was 47.51±12.53 (range 17-76) years, 106 patients died and disease duration was 13.20±9.04 (range 2-48) months. Insomnia (87.0%) and rapidly progressive dementia (RPD; 83.2%) occurred with the highest frequency. Hypertension (33.6%) was considered to be an objective indicator of autonomic dysfunction. Genotype frequency at codon 129 was Met/Met (84.7%) and Met/Val (15.3%), and allele frequency was Met (92.4%) and Val (7.6%).129 Met was a risk factor (OR: 3.728, 95% CI: 2.194 to 6.333, p=0.000) for FFI in the non-Asian population. Comparison of Asians and non-Asians revealed clinical symptoms and genetic background to show some differences (p<0.05). In the comparison of 129 polymorphisms, a longer disease duration was found in the 129 MV group, with alleviation of some clinical symptoms (p<0.05). After considering survival probability, significant differences in survival time between genotypes remained (p<0.0001). CONCLUSIONS: Insomnia, RPD and hypertension are representative key clinical presentations of FFI. Phenotypic variations in genotypes and geographic regions were documented. Prion protein gene 129 Met was considered to be a risk factor for FFI in the non-Asian population, and 129 polymorphisms could modify survival duration.


Asunto(s)
Genotipo , Insomnio Familiar Fatal/genética , Fenotipo , Polimorfismo de Nucleótido Simple , Proteínas Priónicas/genética , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mutación , Adulto Joven
5.
Front Med (Lausanne) ; 8: 762763, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34859014

RESUMEN

As an opportunistic phytopathogen, Sarocladium strictum has only been shown to cause neurological disease in immunocompromised patients, where antifungal therapy was not effective. We report a case of Sarocladium strictum meningoencephalitis in an apparently immunocompetent young woman who presented with severe headache and slight fever after undergoing transnasal endoscopic repair of cerebrospinal fluid rhinorrhea. Chronic sinusitis and suspicious intracranial fungal lesions were observed on enhanced magnetic resonance imaging (MRI). Both culture and metagenomic next-generation sequencing of her cerebrospinal fluid were positive for Sarocladium strictum. After local debridement, treatment with amphotericin B plus voriconazole and Ommaya reservoir implantation, the patient improved significantly. Unfortunately, her symptoms worsened again despite plenty of antifungal therapy for a month.

6.
Inorg Chem ; 60(3): 1315-1319, 2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-33443994

RESUMEN

New kinds of diradical rare-earth metal complexes supported by diazabutadiene (DAD) ligands, [(DAD)2LnN(TMS)2] (1; Ln = Dy, Lu; TMS = SiMe3), were synthesized and studied. They showed a new [radical-Ln-radical] alignment with distorted square-pyramidal geometry. Structural and density functional theory analysis illustrated the radical anionic nature of the ligands. Magnetic studies revealed antiferromagnetic coupling of the two radicals in 1-Lu. 1-Dy showed typical single-molecule-magnet (SMM) behavior with an effective energy barrier of 231 K, which is much higher than those of similar radical-containing SMMs. Magnetostructural analysis suggests that the anionic [N(TMS)2]- group plays a vital role in the SMM property. This study provides a new platform for further improving the performance of radical-Ln SMMs.

7.
Org Lett ; 19(10): 2694-2697, 2017 05 19.
Artículo en Inglés | MEDLINE | ID: mdl-28481555

RESUMEN

CuOTf-catalyzed substituent-controlled cascade [2 + 2 + 2] and [4 + 2] annulation reactions among heterocumulenes, alkynes, and diaryliodonium salts were achieved. Various quinoline derivatives could be obtained in good yields with excellent selectivity. This methodology provided a novel pathway to activate heterocumulenes via a unique highly reactive cationic intermediate. The reaction process was well elucidated by density functional theory calculations.

8.
Chemistry ; 23(4): 757-761, 2017 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-27898999

RESUMEN

The selective C(sp3 )-H bond functionalization is an ideal and atom-economical method in organic synthesis. In this work, 2-aminopyrimidines are generated from a Cu-catalyzed reaction between carbodiimides and diaryliodonium salts, by cleavage of four C(sp3 )-H, one C-N, and one C=N bonds in the carbodiimides. It is the first triple C(sp3 )-H bond functionalization neighboring a C=N bond. The selective synthesis of 2-aminopyrimidines is controlled by the amount of the diaryliodonium salts. The novel mechanism involving a C-N formation/1,5-H shift/1,7-H shift/6 π-electrocyclic ring-closing/aromatization is well elucidated by the detection of important intermediates and DFT calculations.

9.
Chemistry ; 21(29): 10369-78, 2015 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-26013660

RESUMEN

The Zn(OTf)2 -catalyzed guanylation/amidation from readily available amino acid esters and carbodiimides is achieved to provide efficiently various cyclic oxoguanidines, including 2-amino-1H-imidazol-5(4H)-ones and 2-aminoquinazolin-4(3H)-ones in medium-to-high yields. It is the first time that an ammonium salt has been used in a guanylation reaction. The application of cyclic oxoguanidines to provide the conjugated heterocyclic compounds via oxidative C-N formation or aldol reaction is explored. The reaction mechanism is well elucidated by the isolation and characterization of three important intermediates.


Asunto(s)
Aminoácidos/química , Aminoquinolinas/química , Carbodiimidas/química , Guanidinas/síntesis química , Compuestos Heterocíclicos/síntesis química , Imidazoles/química , Mesilatos/química , Catálisis , Ésteres , Guanidinas/química , Compuestos Heterocíclicos/química , Estructura Molecular , Estereoisomerismo
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