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1.
Cell Biochem Funct ; 42(5): e4087, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38953407

RESUMEN

ß-Nicotinamide mononucleotide (NMN) is a biologically active nucleotide that regulates the physiological metabolism of the body by rapidly increasing nicotinamide adenine dinucleotide (NAD+). To determine the safety and biological activity of NMN resources, we constructed a recombinant strain of P. pastoris that heterologously expresses nicotinamide-phosphate ribosyltransferase (NAMPT), and subsequently catalyzed and purified the expressed product to obtain NMN. Consequently, this study established a high-fat diet (HFD) obese model to investigate the lipid-lowering activity of NMN. The findings showed that NMN supplementation directly increased the NAD+ levels, and reduced HFD-induced liver injury and lipid deposition. NMN treatment significantly decreased total cholesterol (TC) and triglyceride (TG) in serum and liver, as well as alanine aminotransferase (ALT) and insulin levels in serum (p < .05 or p < .01). In conclusion, this study combined synthetic biology with nutritional evaluation to confirm that P. pastoris-generated NMN modulated lipid metabolism in HFD mice, offering a theoretical framework and evidence for the application of microbially created NMN.


Asunto(s)
Dieta Alta en Grasa , Metabolismo de los Lípidos , Hígado , Ratones Endogámicos C57BL , Mononucleótido de Nicotinamida , Animales , Mononucleótido de Nicotinamida/metabolismo , Mononucleótido de Nicotinamida/farmacología , Metabolismo de los Lípidos/efectos de los fármacos , Ratones , Hígado/metabolismo , Masculino , Nicotinamida Fosforribosiltransferasa/metabolismo
2.
Front Immunol ; 15: 1405348, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38979421

RESUMEN

Background: Antiretroviral therapy (ART) for HIV-1 treatment has improved lifespan but requires lifelong adherence for people living with HIV (PLWH), highlighting the need for a cure. Evaluation of potential cure strategies requires analytic treatment interruption (ATI) with close monitoring of viral rebound. Predictive biomarkers for HIV-1 rebound and/or duration of control during ATI will facilitate these HIV cure trials while minimizing risks. Available evidence suggests that host immune, glycomic, lipid, and metabolic markers of inflammation may be associated with HIV-1 persistence in PLWH who are treated during chronic HIV-1 infection. Methods: We conducted post-hoc analysis of HIV controllers who could maintain low levels of plasma HIV-1 without ART in a phase 1b vesatolimod trial. Baseline and pre-ATI levels of immune, glycomic, lipidomic, and metabolomic markers were tested for association with ATI outcomes (time of HIV-1 rebound to 200 copies/mL and 1,000 copies/mL, duration of HIV-1 RNA ≤400 copies/mL and change in intact proviral HIV-1 DNA during ATI) using Spearman's correlation and Cox proportional hazards model. Results: Higher levels of CD69+CD8+ T-cells were consistently associated with shorter time to HIV-1 rebound at baseline and pre-ATI. With few exceptions, baseline fucosylated, non-galactosylated, non-sialylated, bisecting IgG N-glycans were associated with shorter time to HIV rebound and duration of control as with previous studies. Baseline plasma MPA and HPA binding glycans and non-galactosylated/non-sialylated glycans were associated with longer time to HIV rebound, while baseline multiply-galactosylated glycans and sialylated glycans, GNA-binding glycans, NPA-binding glycans, WGA-binding glycans, and bisecting GlcNAc glycans were associated with shorter time to HIV rebound and duration of control. Fourteen bioactive lipids had significant baseline associations with longer time to rebound and duration of control, and larger intact proviral HIV-1 DNA changes; additionally, three baseline bioactive lipids were associated with shorter time to first rebound and duration of control. Conclusion: Consistent with studies in HIV non-controllers, proinflammatory glycans, lipids, and metabolites were generally associated with shorter duration of HIV-1 control. Notable differences were observed between HIV controllers vs. non-controllers in some specific markers. For the first time, exploratory biomarkers of ATI viral outcomes in HIV-controllers were investigated but require further validation.


Asunto(s)
Biomarcadores , Infecciones por VIH , VIH-1 , Carga Viral , Humanos , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/inmunología , Infecciones por VIH/sangre , Infecciones por VIH/virología , Biomarcadores/sangre , VIH-1/inmunología , Masculino , Adulto , Femenino , Fármacos Anti-VIH/uso terapéutico , Persona de Mediana Edad , ARN Viral/sangre
3.
Imeta ; 3(1): e165, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38868519

RESUMEN

Consumption of dietary fiber and anthocyanin has been linked to a lower incidence of colorectal cancer (CRC). This study scrutinizes the potential antitumorigenic attributes of a black rice diet (BRD), abundantly rich in dietary fiber and anthocyanin. Our results demonstrate notable antitumorigenic effects in mice on BRD, indicated by a reduction in both the size and number of intestinal tumors and a consequent extension in life span, compared to control diet-fed counterparts. Furthermore, fecal transplants from BRD-fed mice to germ-free mice led to a decrease in colonic cell proliferation, coupled with maintained integrity of the intestinal barrier. The BRD was associated with significant shifts in gut microbiota composition, specifically an augmentation in probiotic strains Bacteroides uniformis and Lactobacillus. Noteworthy changes in gut metabolites were also documented, including the upregulation of indole-3-lactic acid and indole. These metabolites have been identified to stimulate the intestinal aryl hydrocarbon receptor pathway, inhibiting CRC cell proliferation and colorectal tumorigenesis. In summary, these findings propose that a BRD may modulate the progression of intestinal tumors by fostering protective gut microbiota and metabolite profiles. The study accentuates the potential health advantages of whole-grain foods, emphasizing the potential utility of black rice in promoting health.

4.
Org Biomol Chem ; 22(24): 4978-4986, 2024 06 19.
Artículo en Inglés | MEDLINE | ID: mdl-38832762

RESUMEN

Ganoderma lucidum, a fungus used in traditional Chinese medicine, is known for its medicinal value attributed to its active components called Ganoderma triterpenoids (GTs). However, the limited isolation rate of these GTs has hindered their potential as promising drug candidates. Therefore, it is imperative to achieve large-scale preparation of GTs. In this study, four GTs were effectively synthesised from lanosterol. The antitumor activity of these GTs was evaluated in vivo. Endertiin B exhibited potent inhibitory activity against breast cancer cells (9.85 ± 0.91 µM and 12.12 ± 0.95 µM). Further investigations demonstrated that endertiin B significantly upregulated p21 and p27 and downregulated cyclinD1 expression, arresting the cell cycle at the G0/G1 phase and inducing apoptosis by decreasing BCL-2 and increasing BAX and BAK levels. Additionally, endertiin B was found to reduce the expression of proteins associated with the PI3K-AKT signaling pathway. To summarize, endertiin B effectively inhibited cell proliferation by blocking the cell cycle and inducing apoptosis through the PI3K-AKT pathway.


Asunto(s)
Antineoplásicos , Apoptosis , Proliferación Celular , Reishi , Triterpenos , Triterpenos/farmacología , Triterpenos/química , Triterpenos/síntesis química , Triterpenos/aislamiento & purificación , Reishi/química , Humanos , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/síntesis química , Proliferación Celular/efectos de los fármacos , Apoptosis/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Animales , Ratones , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga , Relación Estructura-Actividad , Femenino , Ciclo Celular/efectos de los fármacos , Estructura Molecular
5.
Adv Mater ; : e2404120, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38727702

RESUMEN

This study innovatively addresses challenges in enhancing upconversion efficiency in lanthanide-based nanoparticles (UCNPs) by exploiting Shewanella oneidensis MR-1, a microorganism capable of extracellular electron transfer. Electroactive membranes, rich in c-type cytochromes, are extracted from bacteria and integrated into membrane-integrated liposomes (MILs), encapsulating core-shelled UCNPs with an optically inactive shell, forming UCNP@MIL constructs. The electroactive membrane, tailored to donate electrons through the inert shell, independently boosts upconversion emission under near-infrared excitation (980 or 1550 nm), bypassing ligand-sensitized UCNPs. The optically inactive shell restricts energy migration, emphasizing electroactive membrane electron donation. Density functional theory calculations elucidate efficient electron transfer due to the electroactive membrane hemes' highest occupied molecular orbital being higher than the valence band maximum of the optically inactive shell, crucial for enhancing energy transfer to emitter ions. The introduction of a SiO2 insulator coating diminishes light enhancement, underscoring the importance of unimpeded electron transfer. Luminescence enhancement remains resilient to variations in emitter or sensitizing ions, highlighting the robustness of the electron transfer-induced phenomenon. However, altering the inert shell material diminishes enhancement, emphasizing the role of electron transfer. This methodology holds significant promise for diverse biological applications. UCNP@MIL offers an advantage in cellular uptake, which proves beneficial for cell imaging.

6.
World J Urol ; 42(1): 364, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38819448

RESUMEN

OBJECTIVES: Renal cell carcinoma (RCC) is infrequent among young adults. Few studies reported the outcome of RCC in young adults by pathological subtypes. The purpose of this study was to explore the clinicopathological features, survival outcomes and prognostic factors of young adult patients with clear cell (CCRCC) and non-clear cell renal cell carcinoma (NCCRCC). METHODS: This study included young adult patients aged 18-40 years who were diagnosed as renal cell carcinoma (RCC) between 2012 and 2022 at Peking University Third Hospital. All patients underwent either partial nephrectomy or radical nephrectomy, and some received adjuvant therapy. A comparative analysis was performed to investigate the differences in clinicopathological characteristics between the cohort of CCRCC and NCCRCC. Kaplan-Meier survival analysis was utilized to plot survival curves for young adults with RCC. The univariate and multifactorial prognostic analyses were conducted using the log-rank test and COX proportional hazards model. RESULTS: A total of 300 RCC patients aged 18-40 years were performed, of which 201 were diagnosed with CCRCC (67%) and 99 were diagnosed with NCCRCC(33%). The NCCRCC included 29 cases (9.7%) of chromophobe RCC, 28 cases (9.3%) of MiT family translocation RCC, 22 cases (7.3%) of papillary RCC, 11 cases (3.7%) of low malignant potential multifocal cystic RCC, and 6 cases of unclassified RCC (2.0%), 2 cases of mucinous tubule and spindle cell carcinoma (0.7%), and 1 case of FH-deficient RCC (0.3%).The mean age was 33.4 ± 6.1 years old. The overall and progression free 5-year survival rate was 99.1 and 95.3%, respectively. The NCCRCC cohort demonstrated a statistically significant decrease in progression-free survival (PFS) rate when compared to the CCRCC cohort (p < 0.001). There was no statistically significant difference observed in overall survival (OS) (p = 0.069). Pathological stage was a significant independent predictor for OS (p = 0.045). Pathological stage and nuclear grade were both independent predictors for PFS (p = 0.020; p = 0.005). CONCLUSIONS: The clinical and pathological features of young adults diagnosed with CCRCC exhibit notable distinctions from those of NCCRCC patients. The survival outcome was significantly influenced by the pathological stage, while both the nuclear grade and pathological stage had a significant impact on tumor progression. This study offered significant contributions to the understanding of the clinicopathological characteristics and prognostic determinants of renal cell carcinoma (RCC) in young adults.


Asunto(s)
Carcinoma de Células Renales , Neoplasias Renales , Humanos , Carcinoma de Células Renales/patología , Carcinoma de Células Renales/mortalidad , Carcinoma de Células Renales/terapia , Neoplasias Renales/patología , Neoplasias Renales/mortalidad , Neoplasias Renales/terapia , Adulto , Masculino , Adulto Joven , Femenino , Pronóstico , Adolescente , Tasa de Supervivencia , Estudios Retrospectivos , Nefrectomía
7.
Light Sci Appl ; 13(1): 65, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38438358

RESUMEN

Exceptional points (EPs), at which two or more eigenvalues and eigenstates of a resonant system coalesce, are associated with non-Hermitian Hamiltonians with gain and/or loss elements. Dynamic encircling of EPs has received significant interest in recent years, as it has been shown to lead to highly nontrivial phenomena, such as chiral transmission in which the final state of the system depends on the encircling handedness. Previously, chiral transmission for a pair of eigenmodes has been realized by establishing a closed dynamical trajectory in parity-time- (PT-) or anti-PT-symmetric systems. Although chiral transmission of symmetry-broken modes, more accessible in practical photonic integrated circuits, has been realized by establishing a closed trajectory encircling EPs in anti-PT-symmetric systems, the demonstrated transmission efficiency is very low due to path-dependent losses. Here, we demonstrate chiral dynamics in a coupled waveguide system that does not require a closed trajectory. Specifically, we explore an open trajectory linking two infinite points having the same asymptotic eigenmodes (not modes in PT- and anti-PT-symmetric systems), demonstrating that this platform enables high-efficiency chiral transmission, with each eigenmode localized in a single waveguide. This concept is experimentally implemented in a coupled silicon waveguide system at telecommunication wavelengths. Our work provides a new evolution strategy for chiral dynamics with superior performance, laying the foundation for the development of practical chiral-transmission devices.

8.
Angew Chem Int Ed Engl ; 63(18): e202401050, 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38444397

RESUMEN

Geminal bis(boronates) are versatile synthetic building blocks in organic chemistry. The fact that they predominantly serve as nucleophiles in the previous reports, however, has restrained their synthetic potential. Herein we disclose the ambiphilic reactivity of α-halogenated geminal bis(boronates), of which the first catalytic utilization was accomplished by merging a formal Heck cross-coupling with a highly diastereoselective allylboration of aldehydes or imines, providing a new avenue for rapid assembly of polyfunctionalized boron-containing compounds. We demonstrated that this cascade reaction is highly efficient and compatible with various functional groups, and a wide range of heterocycles. In contrast to a classical Pd(0/II) scenario, mechanistic experiments and DFT calculations have provided strong evidence for a catalytic cycle involving Pd(I)/diboryl carbon radical intermediates.

9.
Rheumatol Int ; 44(7): 1245-1253, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38538820

RESUMEN

OBJECTIVE: The objective of this study was to analyze and compare the effects of different urate-lowering agents on testicular functions in men with gout in a clinical setting. METHODS: In this prospective cohort study (Clinical Trial Registration Number: NCT04213534), a total of 49 male patients aged 18-45 years with gout were enrolled. They were divided into three groups and received treatment with either allopurinol, febuxostat or benzbromarone for a duration of 3 months. Semen parameters, reproductive hormones and biochemical assessments were evaluated at baseline, month 1, and month 3. RESULTS: Overall, 40 individuals (81.6%) completed the follow-up visits. In allopurinol group, there were no significant differences in semen parameters from baseline to month 3. Most of sperm parameters in febuxostat group did not show notable changes, except for a decrease in sperm motility at month 3(33.6%, [22.9-54.3] vs 48.4%, [27.4-67.6], p = 0.033). However, the total motile sperm count did not differ significantly after febuxostat treatment. Surprisingly, administration of benzbromarone resulted in improved sperm concentration (37.19 M/mL, [29.6-69.92] vs 58.5 M/mL, [49.8-116.6], p = 0.001). There were no significant changes observed in sperm DNA integrity and reproductive hormones in the three groups from baseline to month 3. The incidence of adverse events did not differ significantly among the three groups as well. CONCLUSION: This study is the first to demonstrate that urate-lowering agents, allopurinol and febuxostat, do not have clinically relevant negative effects on sperm quality and reproductive hormones in men with gout, and benzbromarone presents improving sperm concentration. Results provide important preliminary guidance for the development of reproductive health management guidelines for patients RCID with gout.


Asunto(s)
Alopurinol , Benzbromarona , Febuxostat , Supresores de la Gota , Gota , Espermatozoides , Humanos , Masculino , Gota/tratamiento farmacológico , Gota/sangre , Adulto , Estudios Prospectivos , Supresores de la Gota/uso terapéutico , Supresores de la Gota/efectos adversos , Persona de Mediana Edad , Febuxostat/uso terapéutico , Febuxostat/farmacología , Benzbromarona/uso terapéutico , Adulto Joven , Alopurinol/uso terapéutico , Espermatozoides/efectos de los fármacos , Motilidad Espermática/efectos de los fármacos , Análisis de Semen , Adolescente , Recuento de Espermatozoides , Ácido Úrico/sangre
10.
Curr Med Chem ; 2024 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-38310387

RESUMEN

BACKGROUND: The High Mobility Group Nucleosomal Binding Domain 1 Gene (HMGN1) is crucial for epigenetic regulation. However, the specific function of HMGN1 in cancer development is unclear. METHODS: Raw data on HMGN1 expression were procured from Genotype-Tissue Expression (GTEx), the University of Alabama- Birmingham CANcer data analysis Portal (UALCAN), and The Cancer Genome Atlas (TCGA). Thereafter, the pan-cancer analysis was implemented to understand the HMGN1 expression patterns, prognostic value, and immunological features. Furthermore, the Gene Set Enrichment Analysis (GSEA) was executed via R language. In addition, the relationship between HMGN1 and the sensitivity of antitumor drugs was also determined. Finally, real-time PCR (RT-PCR) experiments were carried out. RESULTS: Pan-cancer analysis revealed that HMGN1 was upregulated in several solid tumors and was associated with pathological staging and poor prognosis. In addition, HMGN1 was found to be involved in regulating the tumor microenvironment. The GSEA enrichment analysis indicated that HMGN1 assisted in the regulation of oncogenic processes, especially metabolic and immune pathways. Furthermore, HMGN1 expression was linked to microsatellite instability (MSI) and tumor mutational burden (TMB) across diverse tumor types. RT-PCR assays indicated that HMGN1 was overexpressed in the gastric and breast cancer cell lines and tissues. CONCLUSION: This study highlighted the potential of HMGN1 as a biomarker for pan- - cancer analysis.

11.
J Biomol Struct Dyn ; : 1-13, 2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38381715

RESUMEN

Renal fibrosis plays a crucial role in the progression of renal diseases, yet the lack of effective diagnostic markers poses challenges in scientific and clinical practices. In this study, we employed machine learning techniques to identify potential biomarkers for renal fibrosis. Utilizing two datasets from the GEO database, we applied LASSO, SVM-RFE and RF algorithms to screen for differentially expressed genes related to inflammatory responses between the renal fibrosis group and the control group. As a result, we identified four genes (CCL5, IFITM1, RIPK2, and TNFAIP6) as promising diagnostic indicators for renal fibrosis. These genes were further validated through in vivo experiments and immunohistochemistry, demonstrating their utility as reliable markers for assessing renal fibrosis. Additionally, we conducted a comprehensive analysis to explore the relationship between these candidate biomarkers, immunity, and drug sensitivity. Integrating these findings, we developed a nomogram with a high discriminative ability, achieving a concordance index of 0.933, enabling the prediction of disease risk in patients with renal fibrosis. Overall, our study presents a predictive model for renal fibrosis and highlights the significance of four potential biomarkers, facilitating clinical diagnosis and personalized treatment. This finding presents valuable insights for advancing precision medicine approaches in the management of renal fibrosis.Communicated by Ramaswamy H. Sarma.

12.
Genome Med ; 16(1): 12, 2024 01 12.
Artículo en Inglés | MEDLINE | ID: mdl-38217035

RESUMEN

Optimal integration of transcriptomics data and associated spatial information is essential towards fully exploiting spatial transcriptomics to dissect tissue heterogeneity and map out inter-cellular communications. We present SEDR, which uses a deep autoencoder coupled with a masked self-supervised learning mechanism to construct a low-dimensional latent representation of gene expression, which is then simultaneously embedded with the corresponding spatial information through a variational graph autoencoder. SEDR achieved higher clustering performance on manually annotated 10 × Visium datasets and better scalability on high-resolution spatial transcriptomics datasets than existing methods. Additionally, we show SEDR's ability to impute and denoise gene expression (URL: https://github.com/JinmiaoChenLab/SEDR/ ).


Asunto(s)
Comunicación Celular , Perfilación de la Expresión Génica , Humanos , Análisis por Conglomerados
13.
Biochim Biophys Acta Mol Basis Dis ; 1870(3): 167024, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38242180

RESUMEN

Oxidative stress is the common mechanism of sensorineural hearing loss (SNHL) caused by many factors, such as noise, drugs and ageing. Here, we used tert-butyl hydroperoxide (t-BHP) to cause oxidative stress damage in HEI-OC1 cells and in an in vitro cochlear explant model. We observed lipid peroxidation, iron accumulation, mitochondrial shrinkage and vanishing of mitochondrial cristae, which caused hair cell ferroptosis, after t-BHP exposure. Moreover, the number of TUNEL-positive cells in cochlear explants and HEI-OC1 cells increased significantly, suggesting that t-BHP caused the apoptosis of hair cells. Administration of deferoxamine (DFOM) significantly attenuated t-BHP-induced hair cell loss and disordered hair cell arrangement in cochlear explants as well as HEI-OC1 cell death, including via apoptosis and ferroptosis. Mechanistically, we found that DFOM treatment reduced t-BHP-induced lipid peroxidation, iron accumulation and mitochondrial pathological changes in hair cells, consequently mitigating apoptosis and ferroptosis. Moreover, DFOM treatment alleviated GSH depletion caused by t-BHP and activated the Nrf2 signalling pathway to exert a protective effect. Furthermore, we confirmed that the protective effect of DFOM mainly depended on its ability to chelate iron by constructing Fth1 knockout (KO), TfR1 KO and Nrf2 KO HEI-OC1 cell lines using CRISPR/Cas9 technology and a Flag-Fth1 (overexpression) HEI-OC1 cell line using the FlpIn™ System. Our findings suggest that DFOM is a potential drug for SNHL treatment due to its ability to inhibit apoptosis and ferroptosis by chelating iron and scavenging reactive oxygen species (ROS).


Asunto(s)
Deferoxamina , Ototoxicidad , Humanos , terc-Butilhidroperóxido/toxicidad , terc-Butilhidroperóxido/metabolismo , Deferoxamina/farmacología , Ototoxicidad/metabolismo , Factor 2 Relacionado con NF-E2/genética , Factor 2 Relacionado con NF-E2/metabolismo , Células Ciliadas Auditivas/metabolismo , Hierro/metabolismo
14.
Crit Rev Biotechnol ; 44(2): 191-201, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36592990

RESUMEN

Protein glycosylation is the most complex posttranslational modification process. Most cellulases from filamentous fungi contain N-glycosylation and O-glycosylation. Here, we discuss the potential roles of glycosylation on the characteristics and function of cellulases. The use of certain cultivation, inducer, and alteration of engineering glycosylation pathway can enable the rational control of cellulase glycosylation. Glycosylation does not occur arbitrarily and may tend to modify the 3D structure of cellulases by using specially distributed glycans. Therefore, glycoengineering should be considered comprehensively along with the spatial structure of cellulases. Cellulase glycosylation may be an evolution phenomenon, which has been considered as an economical way for providing different functions from identical proteins. In addition to gene and transcription regulations, glycosylation may be another regulation on the protein expression level. Enhanced understanding of the potential regulatory role of cellulase glycosylation will enable synthetic biology approaches for the development of commercial cellulase.


Asunto(s)
Celulasa , Celulasas , Celulasa/química , Celulasa/genética , Celulasa/metabolismo , Glicosilación , Celulasas/química , Celulasas/genética , Celulasas/metabolismo , Hongos/metabolismo
15.
Angew Chem Int Ed Engl ; 63(4): e202315232, 2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38059757

RESUMEN

General methods for the preparation of geminal bis(boronates) are of great interest due to their widespread applications in organic synthesis. While the terminal gem-diboron compounds are readily accessible, the construction of the sterically encumbered, internal analogues has remained a prominent challenge. Herein, we report a formal umpolung strategy to access these valuable building blocks. The readily available 1,1-diborylalkanes were first converted into the corresponding α-halogenated derivatives, which then serve as electrophilic components, undergoing a formal substitution with a diverse array of nucleophiles to form a series of C-C, C-O, C-S, and C-N bonds. This protocol features good tolerance to steric hindrance and a wide variety of functional groups and heterocycles. Notably, this strategy can also be extended to the synthesis of diaryl and terminal gem-diboron compounds, therefore providing a general approach to various types of geminal bis(boronates).

17.
Org Lett ; 26(14): 2729-2732, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-37294050

RESUMEN

Highly substituted aminotetrahydropyrans were synthesized via sequential C-H functionalizations. The process was initiated with a Pd(II)-catalyzed stereoselective γ-methylene C-H arylation of aminotetrahydropyran, followed by α-alkylation or arylation of the corresponding primary amine. The initial γ-C-H (hetero)arylation was compatible with a range of aryl iodides containing various substituents and provided the corresponding products in moderate to good yields. The subsequent α-alkylation or arylation of the isolated arylated products proceeded with high diastereoselectivity to afford value-added disubstituted aminotetrahydropyrans.

18.
J Magn Reson Imaging ; 59(1): 164-176, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37013673

RESUMEN

BACKGROUND: Poorly controlled type 2 diabetes mellitus (T2DM) is known to result in left ventricular (LV) dysfunction, myocardial fibrosis, and ischemic/nonischemic dilated cardiomyopathy (ICM/NIDCM). However, less is known about the prognostic value of T2DM on LV longitudinal function and late gadolinium enhancement (LGE) assessed with cardiac MRI in ICM/NIDCM patients. PURPOSE: To measure LV longitudinal function and myocardial scar in ICM/NIDCM patients with T2DM and to determine their prognostic values. STUDY TYPE: Retrospective cohort. POPULATION: Two hundred thirty-five ICM/NIDCM patients (158 with T2DM and 77 without T2DM). FIELD STRENGTH/SEQUENCE: 3T; steady-state free precession cine; phase-sensitive inversion recovery segmented gradient echo LGE sequences. ASSESSMENT: Global peak longitudinal systolic strain rate (GLPSSR) was evaluated to LV longitudinal function with feature tracking. The predictive value of GLPSSR was determined with ROC curve. Glycated hemoglobin (HbA1c) was measured. The primary adverse cardiovascular endpoint was follow up every 3 months. STATISTICAL TESTS: Mann-Whitney U test or student's t-test; Intra and inter-observer variabilities; Kaplan-Meier method; Cox proportional hazards analysis (threshold = 5%). RESULTS: ICM/NIDCM patients with T2DM exhibited significantly lower absolute value of GLPSSR (0.39 ± 0.14 vs. 0.49 ± 0.18) and higher proportion of LGE positive (+) despite similar LV ejection fraction, compared to without T2DM. LV GLPSSR was able to predict primary endpoint (AUC 0.73) and optimal cutoff point was 0.4. ICM/NIDCM patients with T2DM (GLPSSR < 0.4) had more markedly impaired survival. Importantly, this group (GLPSSR < 0.4, HbA1c ≥ 7.8%, or LGE (+)) exhibited the worst survival. In multivariate analysis, GLPSSR, HbA1c, and LGE (+) significantly predicted primary adverse cardiovascular endpoint in overall ICM/NIDCM and ICM/NIDCM patients with T2DM. CONCLUSIONS: T2DM has an additive deleterious effect on LV longitudinal function and myocardial fibrosis in ICM/NIDCM patients. Combining GLPSSR, HbA1c, and LGE could be promising markers in predicting outcomes in ICM/NIDCM patients with T2DM. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: 5.


Asunto(s)
Cardiomiopatías , Cardiomiopatía Dilatada , Diabetes Mellitus Tipo 2 , Disfunción Ventricular Izquierda , Humanos , Cardiomiopatía Dilatada/complicaciones , Cardiomiopatía Dilatada/diagnóstico por imagen , Pronóstico , Estudios Retrospectivos , Diabetes Mellitus Tipo 2/complicaciones , Medios de Contraste , Hemoglobina Glucada , Imagen por Resonancia Cinemagnética/métodos , Gadolinio , Función Ventricular Izquierda , Fibrosis , Disfunción Ventricular Izquierda/complicaciones , Disfunción Ventricular Izquierda/diagnóstico por imagen , Isquemia
19.
J Ethnopharmacol ; 322: 117567, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38122909

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Patients with ischemic stroke (IS) often continue to exhibit cerebral microcirculatory dysfunction even after receiving thrombolytic therapy. Enhancing the function of cerebral microvascular endothelia represents a pivotal advancement in the therapeutic strategy for ischemic microcirculatory disturbances. A traditional Chinese medicinal formulation named Shexiang Tongxin Dropping Pills (STDP), has been clinically employed to ameliorate microcirculatory abnormalities. Existing literature attests to the beneficial role of STDP on endothelial cells (ECs). Nevertheless, specific impacts and underlying mechanisms of STDP in rectifying IS-induced cerebral microvascular dysfunction warrant further exploration. AIM OF THE STUDY: This investigation seeks to delineate the effects of STDP on cerebral microvascular endothelial damage induced by ischemic stroke and to elucidate the underlying mechanism involved. MATERIALS AND METHODS: Middle cerebral artery occlusion and reperfusion (MCAO/R) technique was employed to established ischemic stroke model in mice. The therapeutic efficacy of STDP on cerebral microvascular function was assessed through laser speckle contrast imaging, behavioral assays, and histological evaluations. Biochemical markers in the brain tissue, including GSH, SOD, MDA, and ROS, were quantified using specific assay kits. In vitro study, oxygen-glucose deprivation and reperfusion (OGD/R) was performed in bEnd.3 cells. The cytoprotective potential of STDP was then evaluated by measuring cell viability, LDH activity, endothelial permeability, and oxidative stress parameters. Important targets in critical pathway were verified by immunoblotting and immunofluorescence both in mice brain slices and bEnd.3 cells. RESULTS: STDP decrease brain infarct size, repaired microvascular cerebral blood flow and attenuated neurological deficiency in MCAO/R mice. Moreover, STDP abolished MCAO/R-induced oxidative stress which was reflected by rescuing GSH content, restoration of SOD activity and T-AOC, reduction of MDA and ROS. Ex vivo, STDP increased cerebral microvascular endothelial cells viability, abolished oxidative stress and decreased their permeability after ODG/R. Mechanistically, STDP significantly suppressed endothelial ROS-TXNIP mediated the activation of NLRP3 inflammasome in vivo and in vitro. CONCLUSION: STDP improves ischemic stroke-induced cerebral microcirculatory deficits by regulating cerebral microvascular endothelial ROS/TXNIP/NLRP3 signaling pathway.


Asunto(s)
Isquemia Encefálica , Medicamentos Herbarios Chinos , Accidente Cerebrovascular Isquémico , Daño por Reperfusión , Humanos , Ratones , Animales , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Células Endoteliales/metabolismo , Accidente Cerebrovascular Isquémico/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Microcirculación , Transducción de Señal , Infarto de la Arteria Cerebral Media/tratamiento farmacológico , Infarto de la Arteria Cerebral Media/metabolismo , Superóxido Dismutasa/metabolismo , Daño por Reperfusión/metabolismo , Isquemia Encefálica/tratamiento farmacológico , Isquemia Encefálica/metabolismo , Proteínas Portadoras/metabolismo
20.
BJU Int ; 2023 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-37942695

RESUMEN

OBJECTIVE: To reveal the overall sperm retrieval rate (SRR) and range in patients with azoospermia factor c (AZFc) microdeletion azoospermia by microdissection testicular sperm extraction (mTESE) and discuss the differences of preoperative patient factors among studies with various SRRs. PATIENTS AND METHODS: We searched PubMed, Web of Science and Embase until February 2023. All studies reporting SRRs by mTESE and required parameters of patients with AZFc microdeletions were included. The primary outcome was the SRR and, if available, the pregnancy rate (PR) and live-birth rate (LBR) after intracytoplasmic sperm injection were also investigated as secondary outcomes. RESULTS: Eventually 11 cohort studies were included in this review. A total number of 441 patients underwent mTESE and in 275 of them sperm was obtained, reaching an overall SRR of 62.4%. The SRRs among studies had a wide range from 25.0% to 85.7%. The studies reporting higher SRRs generally had older mean ages, and higher follicle-stimulating hormone and testosterone levels. Only four studies provided practical data on pregnancies and live-born children of patients with AZFc microdeletions, so the overall PR and LBR were unavailable. CONCLUSIONS: The overall SRR of patients with AZFc microdeletion azoospermia was 62.4%. The effect of patient factors in SR needs further evidence in future work.

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