Your browser doesn't support javascript.
loading
Montrer: 20 | 50 | 100
Résultats 1 - 20 de 104
Filtrer
1.
Small ; : e2402655, 2024 Jul 01.
Article de Anglais | MEDLINE | ID: mdl-38949408

RÉSUMÉ

Solution Gated Graphene Field-Effect Transistors (SGGT) are eagerly anticipated as an amplification platform for fabricating advanced ultra-sensitive sensors, allowing significant modulation of the drain current with minimal gate voltage. However, few studies have focused on light-matter interplay gating control for SGGT. Herein, this challenge is addressed by creating an innovative photoelectrochemical solution-gated graphene field-effect transistor (PEC-SGGT) functionalized with enzyme cascade reactions (ECR) for Organophosphorus (OPs) detection. The ECR system, consisting of acetylcholinesterase (AChE) and CuBTC nanomimetic enzymes, selectively recognizes OPs and forms o-phenylenediamine (oPD) oligomers sediment on the PEC electrode, with layer thickness related to the OPs concentration, demonstrating time-integrated amplification. Under light stimulation, the additional photovoltage generated on the PEC gate electrode is influenced by the oPD oligomers sediment layer, creating a differentiated voltage distribution along the gate path. PEC-SGGT, inherently equipped with built-in amplification circuits, sensitively captures gate voltage changes and delivers output with an impressive thousandfold current gain. The seamless integration of these three amplification modes in this advanced sensor allows a good linear range and highly sensitive detection of OPs, with a detection limit as low as 0.05 pm. This work provides a proof-of-concept for the feasibility of light-assisted functionalized gate-controlled PEC-SGGT for small molecule detection.

2.
Sci Total Environ ; 931: 172938, 2024 Jun 25.
Article de Anglais | MEDLINE | ID: mdl-38703850

RÉSUMÉ

Cadmium (Cd) is a widely distributed typical environmental pollutant and one of the most toxic heavy metals. It is well-known that environmental Cd causes testicular damage by inducing classic types of cell death such as cell apoptosis and necrosis. However, as a new type of cell death, the role and mechanism of pyroptosis in Cd-induced testicular injury remain unclear. In the current study, we used environmental Cd to generate a murine model with testicular injury and AIM2-dependent pyroptosis. Based on the model, we found that increased cytoplasmic mitochondrial DNA (mtDNA), activated mitochondrial proteostasis stress occurred in Cd-exposed testes. We used ethidium bromide to generate mtDNA-deficient testicular germ cells and further confirmed that increased cytoplasmic mtDNA promoted AIM2-dependent pyroptosis in Cd-exposed cells. Uracil-DNA glycosylase UNG1 overexpression indicated that environmental Cd blocked UNG-dependent repairment of damaged mtDNA to drive the process in which mtDNA releases to cytoplasm in the cells. Interestingly, we found that environmental Cd activated mitochondrial proteostasis stress by up-regulating protein expression of LONP1 in testes. Testicular specific LONP1-knockdown significantly reversed Cd-induced UNG1 protein degradation and AIM2-dependent pyroptosis in mouse testes. In addition, environmental Cd significantly enhanced the m6A modification of Lonp1 mRNA and its stability in testicular germ cells. Knockdown of IGF2BP1, a reader of m6A modification, reversed Cd-induced upregulation of LONP1 protein expression and pyroptosis activation in testicular germ cells. Collectively, environmental Cd induces m6A modification of Lonp1 mRNA to activate mitochondrial proteostasis stress, increase cytoplasmic mtDNA content, and trigger AIM2-dependent pyroptosis in mouse testes. These findings suggest that mitochondrial proteostasis stress is a potential target for the prevention of testicular injury.


Sujet(s)
Cadmium , Mitochondries , Pyroptose , Testicule , Animaux , Cadmium/toxicité , Mâle , Souris , Testicule/effets des médicaments et des substances chimiques , Testicule/métabolisme , Pyroptose/effets des médicaments et des substances chimiques , Mitochondries/métabolisme , Mitochondries/effets des médicaments et des substances chimiques , Polluants environnementaux/toxicité , Homéostasie protéique , Protéines mitochondriales/métabolisme , Exposition environnementale/effets indésirables , ADN mitochondrial , ATP-dependent proteases/métabolisme , Stress protéotoxique
3.
Cell Biol Toxicol ; 40(1): 35, 2024 May 21.
Article de Anglais | MEDLINE | ID: mdl-38771546

RÉSUMÉ

Neural tube defects (NTDs) represent a prevalent and severe category of congenital anomalies in humans. Cadmium (Cd) is an environmental teratogen known to cause fetal NTDs. However, its underlying mechanisms remain elusive. This study aims to investigate the therapeutic potential of lipophagy in the treatment of NTDs, providing valuable insights for future strategies targeting lipophagy activation as a means to mitigate NTDs.We successfully modeled NTDs by Cd exposure during pregnancy. RNA sequencing was employed to investigate the transcriptomic alterations and functional enrichment of differentially expressed genes in NTD placental tissues. Subsequently, pharmacological/genetic (Atg5-/- placentas) experiments confirmed that inducing placental lipophagy can alleviate Cd induced-NTDs. We found that Cd exposure caused NTDs. Further analyzed transcriptomic data from the placentas with NTDs which revealed significant downregulation of low-density lipoprotein receptor associated protein 1(Lrp1) gene expression responsible for positive regulation of low-density lipoprotein cholesterol (LDL-C) transport. Correspondingly, there was an increase in maternal serum/placenta/amniotic fluid LDL-C content. Subsequently, we have discovered that Cd exposure activated placental lipophagy. Pharmacological/genetic (Atg5-/- placentas) experiments confirmed that inducing placental lipophagy can alleviate Cd induced-NTDs. Furthermore, our findings demonstrate that activation of placental lipophagy effectively counteracts the Cd-induced elevation in LDL-C levels. Lipophagy serves to mitigate Cd-induced NTDs by reducing LDL-C levels within mouse placentas.


Sujet(s)
Cadmium , Cholestérol LDL , Anomalies du tube neural , Placenta , Femelle , Animaux , Grossesse , Placenta/métabolisme , Placenta/effets des médicaments et des substances chimiques , Anomalies du tube neural/génétique , Anomalies du tube neural/induit chimiquement , Anomalies du tube neural/métabolisme , Souris , Cadmium/toxicité , Cholestérol LDL/sang , Protéine-1 apparentée au récepteur des LDL/génétique , Protéine-1 apparentée au récepteur des LDL/métabolisme , Souris de lignée C57BL , Souris knockout
4.
Chemosphere ; 358: 142138, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-38670504

RÉSUMÉ

Cadmium (Cd), a well-established developmental toxicant, accumulates in the placentae and disrupts its structure and function. Population study found adverse pregnancy outcomes caused by environmental Cd exposure associated with cell senescence. However, the role of autophagy activation in Cd-induced placental cell senescence and its reciprocal mechanisms are unknown. In this study, we employed animal experiments, cell culture, and case-control study to investigate the above mentioned. We have demonstrated that exposure to Cd during gestation induces placental senescence and activates autophagy. Pharmacological and genetic interventions further exacerbated placental senescence induced by Cd through the suppression of autophagy. Conversely, activation of autophagy ameliorated Cd-induced placental senescence. Knockdown of NBR1 exacerbated senescence in human placental trophoblast cells. Further investigations revealed that NBR1 facilitated the degradation of p21 via LC3B. Our case-control study has demonstrated a positive correlation between placental senescence and autophagy activation in all-cause fetal growth restriction (FGR). These findings offer a novel perspective for mitigating placental aging and placental-origin developmental diseases induced by environmental toxicants.


Sujet(s)
Autophagie , Cadmium , Vieillissement de la cellule , Placenta , Trophoblastes , Autophagie/effets des médicaments et des substances chimiques , Cadmium/toxicité , Femelle , Grossesse , Humains , Vieillissement de la cellule/effets des médicaments et des substances chimiques , Trophoblastes/effets des médicaments et des substances chimiques , Placenta/effets des médicaments et des substances chimiques , Placenta/cytologie , Animaux , Polluants environnementaux/toxicité , Études cas-témoins , Retard de croissance intra-utérin/induit chimiquement , Souris
5.
J Hazard Mater ; 469: 133997, 2024 May 05.
Article de Anglais | MEDLINE | ID: mdl-38508115

RÉSUMÉ

Maternal exposure to glucocorticoids has been associated with adverse outcomes in offspring. However, the consequences and mechanisms of gestational exposure to prednisone on susceptibility to osteoporosis in the offspring remain unclear. Here, we found that gestational prednisone exposure enhanced susceptibility to osteoporosis in adult mouse offspring. In a further exploration of myogenic mechanisms, results showed that gestational prednisone exposure down-regulated FNDC5/irisin protein expression and activation of OPTN-dependent mitophagy in skeletal muscle of adult offspring. Additional experiments elucidated that activated mitophagy significantly inhibited the expression of FNDC5/irisin in skeletal muscle cells. Likewise, we observed delayed fetal bone development, downregulated FNDC5/irisin expression, and activated mitophagy in fetal skeletal muscle upon gestational prednisone exposure. In addition, an elevated total m6A level was observed in fetal skeletal muscle after gestational prednisone exposure. Finally, gestational supplementation with S-adenosylhomocysteine (SAH), an inhibitor of m6A activity, attenuated mitophagy and restored FNDC5/irisin expression in fetal skeletal muscle, which in turn reversed fetal bone development. Overall, these data indicate that gestational prednisone exposure increases m6A modification, activates mitophagy, and decreases FNDC5/irisin expression in skeletal muscle, thus elevating osteoporosis susceptibility in adult offspring. Our results provide a new perspective on the earlier prevention and treatment of fetal-derived osteoporosis.


Sujet(s)
Fibronectines , Ostéoporose , Humains , Souris , Femelle , Animaux , Grossesse , Prednisone/métabolisme , Fibronectines/métabolisme , Exposition maternelle , Mitophagie , Muscles squelettiques/métabolisme , Facteurs de transcription/métabolisme , Ostéoporose/induit chimiquement
6.
J Hazard Mater ; 470: 134142, 2024 May 15.
Article de Anglais | MEDLINE | ID: mdl-38555669

RÉSUMÉ

Low testosterone (T) levels are associated with many common diseases, such as obesity, male infertility, depression, and cardiovascular disease. It is well known that environmental cadmium (Cd) exposure can induce T decline, but the exact mechanism remains unclear. We established a murine model in which Cd exposure induced testicular T decline. Based on the model, we found Cd caused mitochondrial fusion disorder and Parkin mitochondrial translocation in mouse testes. MFN1 overexpression confirmed that MFN1-dependent mitochondrial fusion disorder mediated the Cd-induced T synthesis suppression in Leydig cells. Further data confirmed Cd induced the decrease of MFN1 protein by increasing ubiquitin degradation. Testicular specific Parkin knockdown confirmed Cd induced the ubiquitin-dependent degradation of MFN1 protein through promoting Parkin mitochondrial translocation in mouse testes. Expectedly, testicular specific Parkin knockdown also mitigated testicular T decline. Mito-TEMPO, a targeted inhibitor for mitochondrial reactive oxygen species (mtROS), alleviated Cd-caused Parkin mitochondrial translocation and mitochondrial fusion disorder. As above, Parkin mitochondrial translocation induced mitochondrial fusion disorder and the following T synthesis repression in Cd-exposed Leydig cells. Collectively, our study elucidates a novel mechanism through which Cd induces T decline and provides a new treatment strategy for patients with androgen disorders.


Sujet(s)
Cadmium , Polluants environnementaux , Cellules de Leydig , Testicule , Testostérone , Ubiquitin-protein ligases , Mâle , Animaux , Ubiquitin-protein ligases/métabolisme , Ubiquitin-protein ligases/génétique , Cadmium/toxicité , Testostérone/métabolisme , Testicule/effets des médicaments et des substances chimiques , Testicule/métabolisme , Cellules de Leydig/effets des médicaments et des substances chimiques , Cellules de Leydig/métabolisme , Polluants environnementaux/toxicité , Souris , Mitochondries/effets des médicaments et des substances chimiques , Mitochondries/métabolisme , Souris de lignée C57BL , dGTPases/métabolisme , dGTPases/génétique
7.
Nat Commun ; 15(1): 1353, 2024 Feb 14.
Article de Anglais | MEDLINE | ID: mdl-38355624

RÉSUMÉ

There is strong evidence that obesity is a risk factor for poor semen quality. However, the effects of multigenerational paternal obesity on the susceptibility to cadmium (a reproductive toxicant)-induced spermatogenesis disorders in offspring remain unknown. Here, we show that, in mice, spermatogenesis and retinoic acid levels become progressively lower as the number of generations exposed to a high-fat diet increase. Furthermore, exposing several generations of mice to a high fat diet results in a decrease in the expression of Wt1, a transcription factor upstream of the enzymes that synthesize retinoic acid. These effects can be rescued by injecting adeno-associated virus 9-Wt1 into the mouse testes of the offspring. Additionally, multigenerational paternal high-fat diet progressively increases METTL3 and Wt1 N6-methyladenosine levels in the testes of offspring mice. Mechanistically, treating the fathers with STM2457, a METTL3 inhibitor, restores obesity-reduced sperm count, and decreases Wt1 N6-methyladenosine level in the mouse testes of the offspring. A case-controlled study shows that human donors who are overweight or obese exhibit elevated N6-methyladenosine levels in sperm and decreased sperm concentration. Collectively, these results indicate that multigenerational paternal obesity enhances the susceptibility of the offspring to spermatogenesis disorders by increasing METTL3-mediated Wt1 N6-methyladenosine modification.


Sujet(s)
Infertilité masculine , Analyse du sperme , Animaux , Humains , Mâle , Souris , Alimentation riche en graisse/effets indésirables , Pères , Infertilité masculine/génétique , Methyltransferases , Obésité/métabolisme , Sperme/métabolisme , Trétinoïne
8.
World J Urol ; 42(1): 14, 2024 Jan 08.
Article de Anglais | MEDLINE | ID: mdl-38189837

RÉSUMÉ

PURPOSE: Bladder neck contracture (BNC) is a rare but intolerant complication after transurethral surgery of prostate. The present study aims to investigate the incidence and risk factors of BNC in patients diagnosed benign prostate hyperplasia (BPH) and following transurethral resection or enucleation of the prostate (TURP/TUEP). METHODS: This retrospective study included 1008 BPH individuals who underwent transurethral surgery of the prostate between January 2017 and January 2022. Patients' demographics, medical comorbidities, urologic characteristics, perioperative parameters, and the presence of BNC were documented. Univariate and multivariate analyses were conducted to identify the risk factors. RESULTS: A total of 2% (20/1008) BPH patients developed BNC postoperatively and the median occurring time was 5.8 months. Particularly, the incidences of BNC were 4.7% and 1.3% in patients underwent Bipolar-TURP and TUEP respectively. Preoperative urinary tract infection (UTI), elevated PSA, smaller prostate volume (PV), bladder diverticulum (BD), and B-TURP were significantly associated with BNC in the univariate analysis. Further multivariate logistic regression demonstrated preoperative UTI (OR 4.04, 95% CI 2.25 to 17.42, p < 0.001), BD (OR 7.40, 95% CI 1.83 to 31.66, p < 0.001), and B-TURP (OR 3.97, 95% CI 1.55 to 10.18, p = 0.004) as independent risk factors. All BNC patients were treated with transurethral incision of the bladder neck (TUIBN) combined with local multisite injection of betamethasone. During a median follow-up of 35.8 months, 35% (7/20) of BNC patients recurred at a median time of 1.8 months. CONCLUSION: BNC was a low-frequency complication following transurethral surgery of prostate. Preoperative UTI, BD, and B-TURP were likely independent risk factors of BNC. TUIBN combined with local multisite injection of betamethasone may be promising choice for BNC treatment.


Sujet(s)
Contracture , Hyperplasie de la prostate , Mâle , Humains , Vessie urinaire , Prostate , Études rétrospectives , Hyperplasie de la prostate/chirurgie , Contracture/épidémiologie , Contracture/étiologie , Bétaméthasone
9.
World J Gastrointest Oncol ; 15(10): 1784-1795, 2023 Oct 15.
Article de Anglais | MEDLINE | ID: mdl-37969412

RÉSUMÉ

BACKGROUND: The Khorana risk score (KRS) has poor predictive value for cancer-associated thrombosis in a single tumor type but is associated with early all-cause mortality from cancer. Evidence for the association between KRS and all-cause mortality in Japanese patients with gastric and colorectal cancer is limited. AIM: To investigate whether KRS was independently related to all-cause mortality in Japanese patients with gastric and colorectal cancer after adjusting for other covariates and to shed light on its temporal validity. METHODS: Data from Dryad database were used in this study. Patients in the Gastroenterology Department of Sapporo General Hospital, Sapporo, Japan, were enrolled. The starting and ending dates of the enrollment were January 1, 2008 and January 5, 2015, respectively. The cutoff date for follow-up was May 31, 2016. The independent and dependent (target) variables were the baseline measured using the KRS and final all-cause mortality, respectively. The KRS was categorized into three groups: Low-risk group (= 0 score), intermediate-risk group (1-2 score), and high-risk group (≥ 3 score). RESULTS: Men and patients with Eastern Cooperative Oncology Group Performance Status (ECOG PS) ≥ 2 displayed a higher 2-year risk of death than women and those with ECOG PS 0-1 in the intermediate/high risk group for KRS. The higher the score, the higher the risk of early death; however, the relevance of this independent prediction decreased with longer survival. The overall survival of each patient was recorded via real-world follow-up and retrospective observations, and this study yielded the overall relationship between KRS and all-cause mortality. CONCLUSION: The prechemotherapy baseline of KRS was independently associated with all-cause mortality within 2 years; however, this independent predictive relationship weakened as survival time increased.

10.
Inorg Chem ; 62(49): 20513-20519, 2023 Dec 11.
Article de Anglais | MEDLINE | ID: mdl-38008909

RÉSUMÉ

With the development of crystalline porous materials toward methane storage, the stability issue of metal-organic framework (MOF) materials has caused great concern despite high working capacity. Considering the high stability of zirconium-based MOFs and effective functions of amide groups toward gas adsorption, herein, a series of UiO-66 type of Zr-MOFs, namely, Zr-fcu-H/F/CH3/OH, were successfully designed and synthesized by virtue of amide-functionalized dicarboxylate ligands bearing distinct side groups (i.e., -H, -F, -CH3, and -OH) and ZrCl4 in the presence of trifluoroacetic acid as the modulator. Single-crystal X-ray diffraction and topology analyses reveal that these compounds are archetypal fcu MOFs encompassing octahedral and tetrahedral cages, respectively. The N2 sorption isotherms and acid-base stability tests demonstrate that the materials possess not only relatively high surface areas, pore volumes, and appropriate pore sizes but also great hydrolytic stabilities ranging pH = 3-11. Furthermore, the volumetric methane storage working capacities of Zr-fcu-H, Zr-fcu-F, Zr-fcu-CH3, and Zr-fcu-OH at 298/273 K and 80 bar are 187/217, 175/193, 167/187, and 154/171 cm3 (STP) cm-3, respectively, which indicate that the zirconium-based crystalline porous materials are capable of storing relatively high amounts of methane.

11.
Nat Prod Res ; : 1-4, 2023 Sep 15.
Article de Anglais | MEDLINE | ID: mdl-37712410

RÉSUMÉ

Phytochemical investigation of EtOH extract of Pittosporum heterophyllum led to one new esterified thujane monoterpenoid glycoside, pitheteroside A (1), together with one eudesmane sesquiterpenoid (2) and twelve lignans (3-14). Their structures were elucidated by extensive spectroscopic analysis, including 1D and 2D NMR, ECD calculation and HRESIMS spectra. Pitheteroside A is an unreported and highly esterified monoterpenoid glycoside. All isolates were evaluated for their nitric oxide production inhibition against LPS-induced BV-2 microglial cells. Among them, compounds 1, 6 and 8 showed significant activities with IC50 values less than 10 µM. The results indicated the metabolisms from P. heterophyllum possess potential anti-inflammatory effects.

12.
Nanoscale ; 15(37): 15079-15091, 2023 Sep 29.
Article de Anglais | MEDLINE | ID: mdl-37697950

RÉSUMÉ

With their excellent biocompatibility, adjustable size, and high specific surface area, silica nanoparticles (SiO2 NPs) offer an alternative to traditional bulk fertilizers as a means to promote sustainable agriculture. SiO2 NPs have been shown to promote the growth of plants and to reduce the negative effects of biotic and abiotic stresses, but their bioaccumulation is a crucial factor that has been overlooked in studies of their biological effects. In this review, the techniques to quantify and visualize SiO2 NPs in plants were examined first. We then provide a summary of the current state of knowledge on the accumulation, translocation, and transformation of SiO2 NPs in plants and of the factors (e.g., the physicochemical properties of SiO2 NPs, plant species, application mode, and environmental conditions) that influence SiO2 NP bioaccumulation. The challenges in analyzing NP-plant interactions are considered as well. We conclude by identifying areas for further research that will advance our understanding of NP-plant interactions and thus contribute to more sustainable, eco-friendly, nano-enabled approaches to improving crop nutrient supplies. The information presented herein is important to improve the delivery efficiency of SiO2 NPs for precision and sustainable agriculture and to assess the safety of SiO2 NPs during their application in agriculture.


Sujet(s)
Nanoparticules , Silice , Silice/composition chimique , Nanoparticules/composition chimique , Plantes , Engrais
13.
Food Chem Toxicol ; 179: 113967, 2023 Sep.
Article de Anglais | MEDLINE | ID: mdl-37506864

RÉSUMÉ

Cadmium (Cd), one of the most common contaminants in diet and drinking water, impairs testicular germ cell development and spermatogenesis. Autophagy is essential for maintaining Sertoli cell function and Sertoli-germ cell communication. However, the role of Sertoli cell autophagy in Cd-caused spermatogenesis disorder remains unclear. Here, the mice of autophagy-related gene 5 (Atg5) knockouts in Sertoli cells were used to investigate the effect of autophagy deficiency on Cd-impaired spermatogenesis and its underlying mechanisms. Results showed that Sertoli cell-specific knockout of Atg5 exacerbated Cd-reduced sperm count and MVH (a specific marker for testicular germ cells) level in mice. Additionally, Sertoli cell Atg5 deficiency reduced the number of spermatocytes and decreased the level of meiosis-related proteins (SYCP3 and STRA8) in Cd-treated mouse testes. Loss of Atg5 in Sertoli cell exacerbated Cd-reduced the level of retinoic acid (RA) and retinal dehydrogenase (ALDH1A1 and ALDH1A) in mouse testes. Meanwhile, we found that the level of transcription factor WT1 was significantly downregulated in Atg5-/- plus Cd-treated testes. Further experiments showed that Wt1 overexpression restored Cd-decreased the levels of ALDH1A1 in Sertoli cells. Collectively, the above data suggest that knockout of Atg5 in Sertoli cell enhances the susceptibility of Cd-impaired testicular spermatogenesis. These findings provide new insights into autophagy of Sertoli cell preventing environmental toxicants-impaired testicular spermatogenesis.


Sujet(s)
Infertilité masculine , Testicule , Humains , Mâle , Souris , Animaux , Cellules de Sertoli , Cadmium/métabolisme , Sperme , Spermatogenèse , Souris knockout , Protéine-5 associée à l'autophagie
14.
J Hazard Mater ; 458: 131891, 2023 09 15.
Article de Anglais | MEDLINE | ID: mdl-37354721

RÉSUMÉ

Little is currently known about the effect and mechanism of combined paternal environmental cadmium (Cd) and high-fat diet (HFD) on offspring cognitive ability. Here, using in vivo model, we found that combined paternal environmental Cd and HFD caused hippocampal neuronal senescence and cognitive deficits in offspring. MeRIP-seq revealed m6A level of Rhoa, a regulatory gene of cellular senescence, was significantly increased in combined environmental Cd and HFD-treated paternal sperm. Interestingly, combined paternal environmental Cd and HFD markedly enhanced Rhoa mRNA, its m6A and reader protein IGF2BP1 in offspring hippocampus. STM2457, the inhibitor of m6A modification, markedly mitigated paternal exposure-caused the elevation of hippocampal Rhoa m6A, neuronal senescence and cognitive deficits in offspring. In vitro experiments, Rhoa siR significantly reversed mouse hippocampal neuronal senescence. Igf2bp1 siR obviously reduced the level and stability of Rhoa in aging mouse hippocampal neuronal cells. In conclusion, combined paternal environmental Cd and HFD induce offspring hippocampal neuronal senescence and cognitive deficits by promoting IGF2BP1-mediated Rhoa stabilization in offspring hippocampus via elevating Rhoa m6A in paternal sperm.


Sujet(s)
Cadmium , Alimentation riche en graisse , Animaux , Mâle , Souris , Cadmium/métabolisme , Cognition , Hippocampe/métabolisme , Sperme , Spermatozoïdes
15.
Angew Chem Int Ed Engl ; 62(27): e202302983, 2023 Jul 03.
Article de Anglais | MEDLINE | ID: mdl-37154671

RÉSUMÉ

Transition-metal catalyzed enantioconvergent cross-coupling of tertiary alkyl halides with ammonia offers a rapid avenue to chiral unnatural α,α-disubstituted amino acids. However, the construction of chiral C-N bonds between tertiary-carbon electrophiles and nitrogen nucleophiles presented a great challenge owing to steric congestion. We report a copper-catalyzed enantioconvergent radical C-N cross-coupling of alkyl halides with sulfoximines (as ammonia surrogates) under mild conditions by employing a chiral anionic N,N,N-ligand with a long spreading side arm. An array of α,α-disubstituted amino acid derivatives were obtained with good efficiency and enantioselectivity. The synthetic utility of the strategy has been showcased by the elaboration of the coupling products into different chiral α-fully substituted amine building blocks.

16.
J Asian Nat Prod Res ; 25(11): 1044-1050, 2023 Nov.
Article de Anglais | MEDLINE | ID: mdl-37042722

RÉSUMÉ

Two new alkaloids, spongimides A (1) and B (2), along with five known ones (3-7), were isolated from the marine sponge Spongia sp. The structures of 1 and 2 were determined by the spectroscopic methods (UV, IR, MS, and NMR) and X-ray diffraction analysis. Compounds 1, 3, and 4 were the first examples of 2,4-imidazolidinediones isolated from this genus. In addition, the cytotoxic and antibacterial activities of compounds 1 and 2 were also evaluated.


Sujet(s)
Alcaloïdes , Antinéoplasiques , Porifera , Animaux , Structure moléculaire , Porifera/composition chimique , Antinéoplasiques/composition chimique , Alcaloïdes/composition chimique , Spectroscopie par résonance magnétique
17.
Environ Pollut ; 328: 121602, 2023 Jul 01.
Article de Anglais | MEDLINE | ID: mdl-37031847

RÉSUMÉ

Cadmium (Cd), an environmental contaminant, can result in placental non-selective autophagy activation and fetal growth restriction (FGR). However, the role of placental lipophagy, a selective autophagy, in Cd-induced FGR is unclear. This work uses case-control study, animal experiments and cultures of primary human placental trophoblast cells to explore the role of placental lipophagy in Cd-induced FGR. We found association of placental lipophagy and all-cause FGR. Meanwhile, pregnancy Cd exposure induced FGR and placental lipophgay. Inhibition of placental lipophagy by pharmacological and genetic means (Atg5-/- mice) exacerbated Cd-caused FGR. Inversely, activating of placental lipophagy relieved Cd-stimulated FGR. Subsequently, we found that activation of Atg5-dependent lipophagy degrades lipid droplets to produce free cholesterol, and promotes placental progesterone (P4) synthesis. Gestational P4 supplementation significantly reversed Cd-induced FGR. Altogether, activation of Atg5-dependent placental lipophagy ameliorates Cd-induced FGR.


Sujet(s)
Cadmium , Placenta , Grossesse , Femelle , Humains , Animaux , Souris , Placenta/métabolisme , Cadmium/toxicité , Cadmium/métabolisme , Retard de croissance intra-utérin/induit chimiquement , Études cas-témoins , Autophagie , Protéine-5 associée à l'autophagie/génétique , Protéine-5 associée à l'autophagie/métabolisme
18.
Food Chem Toxicol ; 176: 113807, 2023 Jun.
Article de Anglais | MEDLINE | ID: mdl-37121429

RÉSUMÉ

Cadmium (Cd), commonly found in diet and drinking water, is known to be harmful to the human liver. Nevertheless, the effects and mechanisms of gestational Cd exposure on fetal liver development remain unclear. Here, we reported that gestational Cd (150 mg/L) exposure obviously downregulated the expression of critical proteins including PCNA, Ki67 and VEGF-A in proliferation and angiogenesis in fetal livers, and lowered the estradiol concentration in fetal livers and placentae. Maternal estradiol supplement alleviated aforesaid impairments in fetal livers. Our data showed that the levels of pivotal estrogen synthases, such as CYP17A1 and 17ß-HSD, was markedly decreased in Cd-stimulated placentae but not fetal livers. Ground on ovariectomy (OVX), we found that maternal ovarian-derived estradiol had no major effects on Cd-impaired development in fetal liver. In addition, Cd exposure activated placental PERK signaling, and inhibited PERK activity could up-regulated the expressions of CYP17A1 and 17ß-HSD in placental trophoblasts. Collectively, gestational Cd exposure inhibited placenta-derived estrogen synthesis via activating PERK signaling, and therefore impaired fetal liver development. This study suggests a protective role for placenta-derived estradiol in fetal liver dysplasia shaped by toxicants, and provides a theoretical basis for toxicants to impede fetal liver development by disrupting the placenta-fetal-liver axis.


Sujet(s)
Cadmium , Trophoblastes , Grossesse , Femelle , Humains , Cadmium/toxicité , Cadmium/métabolisme , Trophoblastes/métabolisme , Placenta/métabolisme , Foie/métabolisme , Oestradiol , Oestrogènes
19.
Can J Gastroenterol Hepatol ; 2022: 8084431, 2022.
Article de Anglais | MEDLINE | ID: mdl-36387035

RÉSUMÉ

Objectives: The aim of the study is to develop a nomogram for predicting postoperative portal venous systemic thrombosis (PVST) in patients with cirrhosis undergoing splenectomy and esophagogastric devascularization. Methods: In total, 195 eligible patients were included. Demographic characteristics were collected, and the results of perioperative routine laboratory investigations and ultrasound examinations were also recorded. Blood cell morphological traits, including the red cell volume distribution width (RDW), mean platelet volume, and platelet distribution width, were identified. Univariate and multivariate logistic regressions were implemented for risk factor filtration, and an integrated nomogram was generated and then validated using the bootstrap method. Results: A color Doppler abdominal ultrasound examination on a postoperative day (POD) 7 (38.97%) revealed that 76 patients had PVST. The results of the multivariate logistic regression suggested that a higher RDW on POD3 (RDW3) (odds ratio (OR): 1.188, 95% confidence interval (CI): 1.073-1.326), wider portal vein diameter (OR: 1.387, 95% CI: 1.203-1.642), history of variceal hemorrhage (OR: 3.407, 95% CI: 1.670-7.220), and longer spleen length (OR: 1.015, 95% CI: 1.001-1.029) were independent risk parameters for postoperative PVST. Moreover, the nomogram integrating these four parameters exhibited considerable capability in PVST forecasting. The nomogram's receiver operating characteristic curve reached 0.83 and achieved a sensitivity and specificity of 0.711 and 0.848, respectively, at its cutoff. The nomogram's calibration curve demonstrated that it was well calibrated. Conclusion: The nomogram exhibited excellent performance in PVST prediction and might assist surgeons in identifying vulnerable patients and administering timely prophylaxis.


Sujet(s)
Varices oesophagiennes et gastriques , Hypertension portale , Thrombose veineuse , Humains , Splénectomie/effets indésirables , Splénectomie/méthodes , Varices oesophagiennes et gastriques/chirurgie , Varices oesophagiennes et gastriques/complications , Hypertension portale/complications , Hypertension portale/chirurgie , Nomogrammes , Complications postopératoires/épidémiologie , Complications postopératoires/étiologie , Complications postopératoires/prévention et contrôle , Hémorragie gastro-intestinale/complications , Thrombose veineuse/étiologie , Cirrhose du foie/complications , Cirrhose du foie/chirurgie
20.
J Am Chem Soc ; 144(39): 18081-18089, 2022 10 05.
Article de Anglais | MEDLINE | ID: mdl-36153984

RÉSUMÉ

The copper-catalyzed enantioselective intermolecular radical 1,2-carboamination of alkenes with readily accessible alkyl halides is an appealing strategy for producing chiral amine scaffolds. The challenge arises from the easily occurring atom transfer radical addition between alkyl halides and alkenes and the issue of enantiocontrol. We herein describe a radical alkene 1,2-carboamination with sulfoximines in a highly chemo- and enantioselective manner. The key to the success of this process is the conceptual design of a counterion/highly sterically demanded ligand coeffect to promote the ligand exchange of copper(I) with sulfoximines and forge chiral C-N bonds between alkyl radicals and the chiral copper(II) complex. The reaction covers alkenes bearing distinct electronic properties, such as aryl-, heteroaryl-, carbonyl-, and aminocarbonyl-substituted ones, and various radical precursors, including alkyl chlorides, bromides, iodides, and the CF3 source. Facile transformations deliver many chiral amine building blocks of interest in organic synthesis and related areas.


Sujet(s)
Alcènes , Cuivre , Alcènes/composition chimique , Amines , Bromures , Catalyse , Chlorures , Cuivre/composition chimique , Iodures/composition chimique , Ligands , Structure moléculaire , Stéréoisomérie
SÉLECTION CITATIONS
DÉTAIL DE RECHERCHE
...