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1.
J Cell Physiol ; 239(2): e31129, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38192063

RESUMO

Myelodysplastic syndromes (MDS) are a group of heterogeneous myeloid clonal disorders characterized by ineffective hematopoiesis. Accumulating evidence has shown that macrophages (MΦs) are important components in the regulation of tumor progression and hematopoietic stem cells (HSCs). However, the roles of bone marrow (BM) MΦs in regulating normal and malignant hematopoiesis in different clinical stages of MDS are largely unknown. Age-paired patients with lower-risk MDS (N = 15), higher-risk MDS (N = 15), de novo acute myeloid leukemia (AML) (N = 15), and healthy donors (HDs) (N = 15) were enrolled. Flow cytometry analysis showed increased pro-inflammatory monocyte subsets and a decreased classically activated (M1) MΦs/alternatively activated (M2) MΦs ratio in the BM of patients with higher-risk MDS compared to lower-risk MDS. BM MФs from patients with higher-risk MDS and AML showed impaired phagocytosis activity but increased migration compared with lower-risk MDS group. AML BM MΦs showed markedly higher S100A8/A9 levels than lower-risk MDS BM MΦs. More importantly, coculture experiments suggested that the HSC supporting abilities of BM MΦs from patients with higher-risk MDS decreased, whereas the malignant cell supporting abilities increased compared with lower-risk MDS. Gene Ontology enrichment comparing BM MΦs from lower-risk MDS and higher-risk MDS for genes was involved in hematopoiesis- and immunity-related pathways. Our results suggest that BM MΦs are involved in ineffective hematopoiesis in patients with MDS, which indicates that repairing aberrant BM MΦs may represent a promising therapeutic approach for patients with MDS.


Assuntos
Infecções , Macrófagos , Síndromes Mielodisplásicas , Humanos , Medula Óssea/patologia , Hematopoese , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Macrófagos/patologia , Síndromes Mielodisplásicas/genética , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Infecções/patologia
2.
Curr Issues Mol Biol ; 46(3): 1851-1864, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38534737

RESUMO

Autism spectrum disorder (ASD) is thought to result from susceptibility genotypes and environmental risk factors. The offspring of women who experience pregnancy infection have an increased risk for autism. Maternal immune activation (MIA) in pregnant animals produces offspring with autistic behaviors, making MIA a useful model for autism. However, how MIA causes autistic behaviors in offspring is not fully understood. Here, we show that NKCC1 is critical for mediating autistic behaviors in MIA offspring. We confirmed that MIA induced by poly(I:C) infection during pregnancy leads to autistic behaviors in offspring. We further demonstrated that MIA offspring showed significant microglia activation, excessive dendritic spines, and narrow postsynaptic density (PSD) in their prefrontal cortex (PFC). Then, we discovered that these abnormalities may be caused by overexpression of NKCC1 in MIA offspring's PFCs. Finally, we ameliorated the autistic behaviors using PFC microinjection of NKCC1 inhibitor bumetanide (BTN) in MIA offspring. Our findings may shed new light on the pathological mechanisms for autism caused by pregnancy infection.

3.
Br J Haematol ; 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39334557

RESUMO

Patients with relapsed/refractory acute myeloid leukaemia (R/R AML), especially those who failed in novel target agents are related to dismal survival. We developed a multi-institutional, single-arm, prospective phase II trial, to investigate intensified conditioning with 'Mega-Dose' decitabine (MegaDAC) following allogeneic haematopoietic cell transplantation (allo-HCT) for R/R AML. From 2019 to 2023, 70 heavily treated R/R AML patients in active disease were consecutively enrolled. Significantly, every patient (n = 18) harbouring specific mutations exhibited no response to their best available target agents (BATs). Moreover, 74.3% of the enrolled patients did not reach remission following venetoclax-based regimens. All patients underwent intravenous decitabine (400 mg/m2) along with busulfan and cyclophosphamide. Median follow-up was 26 months (8-65) after HCT. All engrafted patients achieved MRD negativity post-HCT, with a median 3.3-log reduction in recurrent genetic abnormalities. The regimen was well tolerated, without irreversible grades III-IV toxicity peri-engraftment. The estimated 2-year CIR was 29.6% (18.4%-41.7%) and the est-2-year NRM was 15.5% (7.8%-25.5%). The est-2-year LFS, OS, and GRFS were 55.0% (43.5%-69.4%), 58.6% (47.0%-73.0%), and 42.9% (31.9%-57.6%), respectively. Multivariate analysis showed that pre-HCT drug exposures had no significant impact on primary outcomes. MegaDAC is highlighted as an effective and safe option for R/R AML in the new era of targeted therapies.

4.
Br J Haematol ; 205(4): 1477-1488, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39099079

RESUMO

The objective of this study was to identify independent prognostic factors of viral encephalitis (VE) after allogeneic haematopoietic stem cell transplantation (allo-HSCT) and establish a prognostic model to identify post-transplant VE patients with a greater likelihood of mortality. Among 5380 patients in our centre from 2014 to 2022, 211 patients who developed VE after allo-HSCT were reviewed in this retrospective study. Prognostic factors were selected, and a prognostic model was constructed using Cox regression analysis. The model was subsequently validated and estimated using the area under the receiver operating characteristic curve (AUC), a calibration plot and decision curve analysis (DCA). Glasgow Coma Scale score <9, lesions >3 lobes on magnetic resonance imaging and severe thrombocytopenia were identified as independent prognostic risk factors for VE patients who underwent allo-HSCT. The prognostic model GTM (GTM is an abbreviation for a model composed of three risk factors: GCS score <9, severe thrombocytopenia [platelet count <20 000 per microliter], and lesions >3 lobes on MRI) was established according to the regression coefficients. The validated internal AUC was 0.862 (95% confidence interval [CI], 0.773-0.950), and the external AUC was 0.815 (95% CI, 0.708-0.922), indicating strong discriminatory ability. Furthermore, we constructed calibration plots that demonstrated good consistency between the predicted outcomes and the observed outcomes. DCA exhibited high accuracy in this system, leading to potential benefits for patients.


Assuntos
Encefalite Viral , Transplante de Células-Tronco Hematopoéticas , Humanos , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Masculino , Feminino , Encefalite Viral/etiologia , Encefalite Viral/diagnóstico , Adulto , Prognóstico , Estudos Retrospectivos , Pessoa de Meia-Idade , Adolescente , Fatores de Risco , Trombocitopenia/etiologia , Transplante Homólogo/efeitos adversos , Criança , Imageamento por Ressonância Magnética , Adulto Jovem
5.
BMC Med ; 22(1): 85, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38413930

RESUMO

BACKGROUND: For patients with steroid-refractory acute graft-versus-host disease (SR-aGVHD), effective second-line regimens are urgently needed. Mesenchymal stromal cells (MSCs) have been used as salvage regimens for SR-aGVHD in the past. However, clinical trials and an overall understanding of the molecular mechanisms of MSCs combined with basiliximab for SR-aGVHD are limited, especially in haploidentical haemopoietic stem cell transplantation (HID HSCT). METHODS: The primary endpoint of this multicentre, randomized, controlled trial was the 4-week complete response (CR) rate of SR-aGVHD. A total of 130 patients with SR-aGVHD were assigned in a 1:1 randomization schedule to the MSC group (receiving basiliximab plus MSCs) or control group (receiving basiliximab alone) (NCT04738981). RESULTS: Most enrolled patients (96.2%) received HID HSCT. The 4-week CR rate of SR-aGVHD in the MSC group was obviously better than that in the control group (83.1% vs. 55.4%, P = 0.001). However, for the overall response rates at week 4, the two groups were comparable. More patients in the control group used ≥ 6 doses of basiliximab (4.6% vs. 20%, P = 0.008). We collected blood samples from 19 consecutive patients and evaluated MSC-derived immunosuppressive cytokines, including HO1, GAL1, GAL9, TNFIA6, PGE2, PDL1, TGF-ß and HGF. Compared to the levels before MSC infusion, the HO1 (P = 0.0072) and TGF-ß (P = 0.0243) levels increased significantly 1 day after MSC infusion. At 7 days after MSC infusion, the levels of HO1, GAL1, TNFIA6 and TGF-ß tended to increase; however, the differences were not statistically significant. Although the 52-week cumulative incidence of cGVHD in the MSC group was comparable to that in the control group, fewer patients in the MSC group developed cGVHD involving ≥3 organs (14.3% vs. 43.6%, P = 0.006). MSCs were well tolerated, no infusion-related adverse events (AEs) occurred and other AEs were also comparable between the two groups. However, patients with malignant haematological diseases in the MSC group had a higher 52-week disease-free survival rate than those in the control group (84.8% vs. 65.9%, P = 0.031). CONCLUSIONS: For SR-aGVHD after allo-HSCT, especially HID HSCT, the combination of MSCs and basiliximab as the second-line therapy led to significantly better 4-week CR rates than basiliximab alone. The addition of MSCs not only did not increase toxicity but also provided a survival benefit.


Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Humanos , Basiliximab/uso terapêutico , Doença Enxerto-Hospedeiro/tratamento farmacológico , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Esteroides/uso terapêutico , Fator de Crescimento Transformador beta/uso terapêutico , Doença Aguda , Transplante de Células-Tronco Mesenquimais/efeitos adversos
6.
Mol Carcinog ; 63(8): 1588-1598, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38780151

RESUMO

Triple-negative breast cancer (TNBC) is a malignant tumor with high degree of malignancy and lack of effective target treatment. The research aims to explore the role and mechanism of X collagen alpha-1 chain protein (COL10A1 gene) in TNBC. UALCAN and Kaplan-Meier were used to detect the expression of COL10A1 and its role in the prognosis of breast cancer patients. The cells with stably expressing high levels of COL10A1 were obtained by recombinant lentivirus infection. The expression of COL10A1 in cells was temporarily downregulated by siRNA interference fragments. Real-time quantitative polymerase chain reaction and western blot analysis were utilized to detect the changes of COL10A1 mRNA and protein expression. The biological functions of the cells were evaluated by colony formation, cell counting kit-8, cell invasion and wound healing experiments. In addition, the effect of COL10A1 on angiogenesis was investigated by tube formation assay. Xenograft tumor model was used to confirm the effect of COL10A1 on tumorigenicity in vivo and multiplex fluorescent immunohistochemistry to detect multiple proteins simultaneously. The possible molecular mechanism of the function of COL10A1 was speculated through the detection of proteins in functionally related pathways. COL10A1 is highly expressed and is significantly associated with worse overall survival (OS) and recurrence-free survival (RFS) in TNBC. Overexpression of COL10A1 increased the clone formation rate and cell migration capacity of TNBC cells. In the COL10A1 overexpression group, the clone formation rates of MD-MB-231 and BT-549 cells (21.5 ± 0.62, 27.83 ± 3.72)% were significantly higher than those in the control group(15.23 ± 2.79, 19.4 ± 1.47)%, and the relative migration ratio (47.40 ± 3.09, 41.26 ± 4.33)% were higher than those in the control group (34.48 ± 2.03, 21.80 ± 1.03)%. When the expression of COL10A1 was downregulated, the ability of clone formation and wound-healing migration capacity in TNBC cells was weakened. Upregulated COL10A1 in TNBC cells generated more junctions and longer total segments between vascular endothelial cells, and promoted angiogenesis of the cells, and thus enhanced the tumorigenesis. In TNBC, it was found that COL10A1 might affect epithelial-mesenchymal transition (EMT) of the cells through Wnt/ß-catenin signaling pathway by the detection of the related pathway proteins. COL10A1 is highly expressed in TNBC, and its high expression leads to poor OS and RFS. COL10A1 may enhance TNBC cell proliferation, migration and tumor-related angiogenesis, and promote tumorigenesis in vivo via Wnt/ß-catenin signaling.


Assuntos
Movimento Celular , Proliferação de Células , Colágeno Tipo X , Regulação Neoplásica da Expressão Gênica , Neoplasias de Mama Triplo Negativas , Via de Sinalização Wnt , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia , Neoplasias de Mama Triplo Negativas/metabolismo , Humanos , Feminino , Via de Sinalização Wnt/genética , Animais , Camundongos , Movimento Celular/genética , Linhagem Celular Tumoral , Colágeno Tipo X/genética , Colágeno Tipo X/metabolismo , Prognóstico , Regulação para Cima , Camundongos Nus , beta Catenina/metabolismo , beta Catenina/genética , Ensaios Antitumorais Modelo de Xenoenxerto , Pessoa de Meia-Idade , Camundongos Endogâmicos BALB C
7.
Inorg Chem ; 63(24): 10943-10948, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38818955

RESUMO

Investigating novel nonlinear optical (NLO) active units serves as a valuable method for broadening the research landscape of NLO materials. This study showcases the potential of the cytosinium cation (C4H6N3O)+ as a novel NLO-active motif through theoretical calculations. The title compound exhibited a wide band gap of 3.85 eV, along with a moderate second harmonic generation (SHG) response of 1.65 times that of KH2PO4 (KDP) and significant birefringence of 0.47. Its exceptional optical properties are primarily attributed to the synergy interaction between cations and anionic groups in the asymmetric unit.

8.
Inorg Chem ; 63(8): 3948-3954, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38350031

RESUMO

The key to searching novel nonlinear optical (NLO) crystals was effectively combining the NLO-active units to obtain a noncentrosymmetric structure. Nevertheless, the present predicament lies in the growing challenge of discovering novel crystals within conventional inorganic frameworks that surpass the properties of the current NLO materials. In view of this, researchers expanded their research focus to the organic-inorganic hybridization system; it is foreseeable to concentrate the advantages from several kinds of NLO-active units to acquire novel NLO crystals with superior properties. We herein report an organic-inorganic hybrid molybdate crystal, namely, [C(NH2)3]6Mo7O24 (GMO). It was successfully obtained via combining inorganic NLO-active MoO6 octahedra and organic π-conjugated [C(NH2)3]+ groups. GMO demonstrates a moderate second-harmonic-generation response, specifically measuring about 1.3 times the value of KDP. Additionally, it exhibits a significant birefringence value of 0.203 at the wavelength of 550 nm and possesses a wide band gap of 3.31 eV. Theoretical calculations suggest that the optical properties of the GMO are primarily influenced by the synergy effect of [C(NH2)3]+ groups between MoO6 octahedra.

9.
Inorg Chem ; 63(10): 4487-4491, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38416696

RESUMO

We herein report an unprecedented organic-inorganic hybrid borate incorporating a novel nonlinear-optical (NLO) active unit, namely, [C(NH2)3][B(C2O2H4)2]. The novel NLO active unit was derived from the condensation reaction between two glycol molecules and one (BO4)5- group. The title compound exhibits a moderate second-harmonic-generation effect (0.7 × KDP), a significant band gap (5.76 eV), and a suitable birefringence (0.078 at 550 nm). The optical properties are determined by the synergistic interaction between the C(NH2)3+ cation and the [B(C2O2H4)2]- group, as indicated by theoretical calculations.

10.
Mol Divers ; 28(1): 125-131, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36881209

RESUMO

Copper-catalyzed selective alkynylation with N-propargyl carboxamides as nucleophiles has been successfully developed for the synthesis of C2-functionalized chromanones. Under optimized reaction conditions, 21 examples were obtained in one-pot procedure through 1,4-conjugate addition. This protocol features readily available feedstocks, easy operations, and moderate to good yields, which provides viable access to pharmacologically active C2-functionalized chromanones.


Assuntos
Cromonas , Cobre , Estrutura Molecular , Catálise
11.
BMC Anesthesiol ; 24(1): 328, 2024 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-39271989

RESUMO

BACKGROUND: To date, the relationship between the Transesophageal Echocardiography (TEE) monitoring indicator tricuspid annular plane systolic excursion (TAPSE) and the incidence of postoperative acute kidney injury (AKI) in Coronary Artery Bypass Grafting(CABG) patients remains unknown. The main objective of this study was to explore the relationship between the TAPSE and the incidence of AKI in CABG patients. METHODS: This was a multicenter prospective cohort study was conducted between September 2021 and July 2022. Among 266 patients aged at least 18 years who underwent elective CABG, 140 were included. RESULTS: We measured TAPSE via M-mode TEE via the mid-esophageal (ME) right ventricle(RV) inflow-outflow view (60°). All echocardiographic measurements were performed three separate times at each time point: T0 (before the start of CABG), T2 (approximately 5 ∼ 10 min after neutralization of protamine) and T3 (before leaving the operating room), and then averaged. Serum creatinine was measured 1 day before and within 7 days after CABG. There was no statistically significant association between the TEE-monitoring indicator TAPSE and the incidence of postoperative AKI in patients who underwent CABG. CONCLUSIONS: The TAPSE was not significantly correlated with postoperative AKI incidence and could not predict the early occurrence of postoperative AKI in CABG patients. TEE needs more evaluation for clinical efficacy of predicting the early occurrence of postoperative AKI in isolated CABG.


Assuntos
Injúria Renal Aguda , Ponte de Artéria Coronária , Ecocardiografia Transesofagiana , Complicações Pós-Operatórias , Valva Tricúspide , Humanos , Ponte de Artéria Coronária/efeitos adversos , Injúria Renal Aguda/epidemiologia , Injúria Renal Aguda/etiologia , Estudos Prospectivos , Feminino , Masculino , Incidência , Ecocardiografia Transesofagiana/métodos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/diagnóstico por imagem , Complicações Pós-Operatórias/etiologia , Idoso , Pessoa de Meia-Idade , Valva Tricúspide/diagnóstico por imagem , Estudos de Coortes
12.
Mol Pain ; 19: 17448069231170072, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37002193

RESUMO

BACKGROUND: Irritable bowel syndrome (IBS) is a common functional gastrointestinal disorder, and its specific pathogenesis is still unclear. We have previously reported that TTX-resistant (TTX-R) sodium channels in colon-specific dorsal root ganglion (DRG) neurons were sensitized in a rat model of visceral hypersensitivity induced by neonatal colonic inflammation (NCI). However, the detailed molecular mechanism for activation of sodium channels remains unknown. This study was designed to examine roles for melatonin (MT) in sensitization of sodium channels in NCI rats. METHODS: Colorectal distention (CRD) in adult male rats as a measure of visceral hypersensitivity. Colon-specific dorsal root ganglion (DRG) neurons were labeled with DiI and acutely dissociated for measuring excitability and sodium channel current under whole-cell patch clamp configurations. Western blot and Immunofluorescence were employed to detect changes in expression of Nav1.8 and MT2. RESULTS: The results showed that rats exhibited visceral hypersensitivity after NCI treatment. Intrathecal application of melatonin significantly increased the threshold of CRD in NCI rats with a dose-dependent manner, but has no role in the control group. Whole-cell patch clamp recording showed that melatonin remarkably decreased the excitability and the density of TTX-R sodium channel in DRG neurons from NCI rats. The expression of MT2 receptor at the protein level was markedly lower in NCI rats. 8MP, an agonist of MT2 receptor, enhanced the distention threshold in NCI rats. Application of 8MP reversed the enhanced hypersensitivity of DRG neurons from NCI rats. 8MP also reduced TTX-R sodium current density and modulated dynamics of TTX-R sodium current activation. CONCLUSIONS: These data suggest that sensitization of sodium channels of colon DRG neurons in NCI rats is most likely mediated by MT2 receptor, thus identifying a potential target for treatment for chronic visceral pain in patients with IBS.


Assuntos
Síndrome do Intestino Irritável , Melatonina , Dor Visceral , Ratos , Animais , Masculino , Síndrome do Intestino Irritável/complicações , Síndrome do Intestino Irritável/tratamento farmacológico , Síndrome do Intestino Irritável/metabolismo , Ratos Sprague-Dawley , Melatonina/farmacologia , Melatonina/uso terapêutico , Melatonina/metabolismo , Dor Visceral/metabolismo , Nociceptividade , Receptor MT2 de Melatonina/metabolismo , Gânglios Espinais/metabolismo , Tetrodotoxina , Canal de Sódio Disparado por Voltagem NAV1.8/metabolismo
13.
Antimicrob Agents Chemother ; 67(1): e0162422, 2023 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-36622172

RESUMO

Vancomycin is recommended for the treatment of skin and soft tissue infections (SSTI) and bone and joint infections (BJI). However, a detailed investigation of the pharmacokinetic profile and optimal dosing regimens of vancomycin in pediatric patients with SSTI and BJI is lacking. We successfully developed a new PopPK model of vancomycin in this population by using scavenged blood samples with the typical values for clearance (CL) of 0.14 L/h/kg and volume of distribution (V) of 0.5 L/kg. Body weight was confirmed as the significant covariate on CL and V. The optimal dosing regimens of 75 mg/kg/day and 80 mg/kg/day were recommended for this specific population.


Assuntos
Infecções dos Tecidos Moles , Vancomicina , Humanos , Criança , Antibacterianos/farmacocinética , Infecções dos Tecidos Moles/tratamento farmacológico , Modelos Biológicos
14.
Br J Haematol ; 200(6): 759-768, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36464324

RESUMO

Prolonged isolated thrombocytopenia (PT) is a life-threatening comorbidity associated with allogeneic haematopoietic stem cell transplantation (allo-HSCT). Our previous study indicated that dysfunctional bone marrow mesenchymal stromal cells (BM MSCs) played a role in PT pathogenesis and that reactive oxygen species (ROS) accumulation was related to BM MSC senescence and apoptosis. However, the mechanism of the increase in ROS levels in the BM MSCs of PT patients is unknown. In the current case-control study, we investigated whether nuclear factor erythroid 2-related factor 2 (NRF2), which is a central regulator of the cellular anti-oxidant response that can clear ROS in human BM MSCs, was associated with PT after allo-HSCT. We evaluated whether an NRF2 agonist (tert-butylhydroquinone, TBHQ) could enhance BM MSCs from PT patients in vitro. We found that BM MSCs from PT patients exhibited increased ROS levels and reduced NRF2 expression. Multivariate analysis showed that low NRF2 expression was an independent risk factor for primary PT [p = 0.032, Odds ratio (OR) 0.868, 95% confidence interval (CI) 0.764-0.988]. In-vitro treatment with TBHQ improved the quantity and function of BM MSCs from PT patients by downregulating ROS levels and rescued the impaired BM MSC support of megakaryocytopoiesis. In conclusion, these results suggested that NRF2 downregulation in human BM MSCs might be involved in the pathogenesis of PT after allo-HSCT and that BM MSC impairment could be improved by NRF2 agonist in vitro. Although further validation is needed, our data indicate that NRF2 agonists might be a potential therapeutic approach for PT patients after allo-HSCT.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Trombocitopenia , Humanos , Medula Óssea/patologia , Estudos de Casos e Controles , Espécies Reativas de Oxigênio/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Transplante Homólogo/efeitos adversos , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Células da Medula Óssea/patologia , Trombocitopenia/etiologia , Células-Tronco Mesenquimais/metabolismo , Transplante de Células-Tronco Mesenquimais/efeitos adversos
15.
Mol Reprod Dev ; 90(10-11): 774-781, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37733694

RESUMO

Male fertility declines with age. The mevalonate pathway, through which cholesterol and nonsteroidal isoprenoids are synthesized, plays key role in metabolic processes and is an essential pathway for cholesterol production and protein prenylation. Male reproductive aging is accompanied by dramatic changes in the metabolic microenvironment of the testis. Since the mevalonate pathway has an important role in spermatogenesis, we attempted to explore the association between male reproductive aging and the mevalonate pathway to explain the mechanism of male reproductive aging. Alterations in the mevalonate pathway may affect male reproductive aging by decreasing cholesterol synthesis and altering testis protein prenylation. Decreased cholesterol levels affect cholesterol modification, testosterone production, and remodeling of germ cell membranes. Aging-related metabolic disorders also affect the metabolic coupling between somatic cells and spermatogenic cells, leading to male fertility decline. Therefore, we hypothesized that alterations in the mevalonate pathway represent one of the metabolic causes of reproductive aging.


Assuntos
Colesterol , Ácido Mevalônico , Masculino , Humanos , Ácido Mevalônico/metabolismo , Colesterol/metabolismo , Reprodução , Testículo/metabolismo
16.
Philos Trans A Math Phys Eng Sci ; 381(2253): 20220213, 2023 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-37393941

RESUMO

A theoretical model that can efficiently calculate the refractive index response of semiconductors under ultrafast X-ray radiation is established based on the photorefractive effect of semiconductors. The proposed model is used to interpret X-ray diagnostics experiments, and the results are in good agreement with experiments. In the proposed model, a rate equation model of free carrier density calculation is adopted with the X-ray absorption cross-sections calculated by atomic codes. The two-temperature model is used to describe the electron-lattice equilibration and the extended Drude model is applied to calculate the transient refractive index change. It is found that faster time response can be achieved for semiconductors with shorter carrier lifetime and sub-picosecond resolution can be obtained for InP and [Formula: see text]. The material response time is not sensitive to X-ray energy and the diagnostics can be used in the 1-10 keV energy range. This article is part of the theme issue 'Dynamic and transient processes in warm dense matter'.

17.
Phys Chem Chem Phys ; 25(43): 29698-29708, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37882726

RESUMO

Two triplet excitons are generated through an ultrafast photophysical process, namely singlet fission (SF), providing a solution for efficient solar energy usage. In this work, we provide an effective guideline for designing SF materials by adjusting the planarity in cyclopentadithiophene (CPDT) derivatives. A practical strategy is proposed for tuning the quinoidal-biradical resonance structures by varying the electron push-pull groups of CPDTs for SF. The localized, delocalized, and intermediate charge-transfer excited configurations are predicted in the singlet excited state via computational simulations, which is further confirmed by ultrafast spectroscopy. Deduced from the potential energy surfaces in the low-lying excited states and transient absorption, the delocalized excited state is formed in 2.1 ps via postulated intramolecular SF in a polar solvent, followed by the ultrafast formation of the free triplet state with a lifetime of 6.8 ps. In comparison with different cross-conjugated chromophores, it is found that the increase in the charge separation could enhance the triplet-pair generation for iSF. We expect that by introducing symmetry-breaking modifications in the electronic configurations and adjusting the separation between the push-pull groups of CPDTs, it should be possible to prolong the duration of the free triplet state by preventing recombination within the triplet-pair excited configuration.

18.
BMC Pediatr ; 23(1): 420, 2023 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-37620840

RESUMO

BACKGROUND: Hepatocellular adenomas (HCAs) are rare benign tumors of the liver that occur predominantly in women taking oral contraceptives. In children, HCAs comprise < 5% of hepatic tumors. We report a case of HCAs in a 7-year-old girl with estrogen and glucose imbalance. CASE PRESENTATION: A 7-year-old girl was presented to our hospital with bilateral breast enlargement for 2 months, polydipsia, polyuria, polyphagia, hyperglycemia, and significant weight gain. Computed tomography (CT) showed a 7.2 cm×6.9 cm×5.3 cm round-shaped mass in the left inner lobe of the liver, ovarian ultrasound showed multiple follicles in the ovaries bilaterally, and cranial magnetic resonance imaging (MRI) showed an enlarged superior pituitary. Hematological and biochemical results were as follows: fasting glucose was 19.7 mmol/L, estradiol was 122.9 pmol/L, follicle-stimulating hormone 10.81 IU/L, luteinizing hormone 10.99 IU/L, insulin-like growth factor 1,513 ng/mL, glutamine aminotransferase 86 U/L, and alkaline phosphatase 362 U/L. Thyroid functions, methemoglobin, fetal protein, carcinoembryonic antigen, and chorionic gonadotropin were normal. The patient had a complete surgical resection of the liver tumor, and the postoperative histopathological diagnosis was HCAs. After the surgery, insulin was injected and the glucose levels were stable. During the 36-month follow-up period, neither tumor recurrence nor significant abnormalities were detected using color Doppler ultrasound of the liver. The child's precocious puberty is currently under control. CONCLUSIONS: HCAs are particularly rare in children with liver tumors, and risk factors for the development of HCAs in children include sex hormone imbalance, obesity, Fanconi anemia (FA), glycogen storage diseases (GSDs) type I, III, and IV, galactosemia, immunodeficiency, congenital portosystemic shunts (CPSS), cardiac hepatopathy status-post Fontan procedure, Hurler syndrome, familial adenomatous polyposis, germline HNF1A mutations, and maturity-onset diabetes of the young type 3. Most HCAs are detected during a physical examination without clinical symptoms, and some patients may present with symptoms such as abdominal pain, abdominal distension, and abdominal masse. Serum liver function tests can show increased alkaline phosphatase (ALP) and γ- glutamyl transferase (GT), whereas α-Fetoprofein (AFP) levels are normal. The definitive diagnosis relies mainly on histopathological examination. Because HCAs can rupture and bleed and become malignant. Early surgical treatment is recommended after detection.


Assuntos
Adenoma de Células Hepáticas , Neoplasias Hepáticas , Criança , Humanos , Feminino , Adenoma de Células Hepáticas/diagnóstico , Adenoma de Células Hepáticas/cirurgia , Fosfatase Alcalina , Recidiva Local de Neoplasia , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/cirurgia
19.
Psychogeriatrics ; 23(2): 319-336, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36683263

RESUMO

BACKGROUND: Depressed patients are often accompanied with constipation symptoms, and vice versa. However, the underlying mechanisms of such a bidirectional correlation have remained elusive. We aim to reveal the possible correlations between depression and constipation from the perspectives of gut microbiome and plasma metabolome. METHODS: We constructed the depressed model and the constipated model of rats, respectively. First, we measured the locomotor activity status and the gastrointestinal functions of rats. And then, nuclear magnetic resonance plasma metabolomics was applied to reveal the shared and the unique metabolites of depression and constipation. In addition, 16 S ribosomal RNA gene sequencing was used to detect the impacts of constipation and depression on gut microbiota of rats. Finally, a multiscale and multifactorial network, that is, the 'phenotypes - differential metabolites - microbial biomarkers' integrated network, was constructed to visualise the mechanisms of connections between depression and constipation. RESULTS: We found that spontaneous locomotor activity and gastrointestinal functions of both depressed rats and constipated rats significantly decreased. Further, eight metabolites and 14 metabolites were associated depression and constipation, respectively. Among them, seven metabolites and four metabolic pathways were shared by constipation and depression, mainly perturbing energy metabolism and amino acid metabolism. Additionally, depression and constipation significantly disordered the functions and the compositions of gut microbiota of rats, and decreased the ratio of Firmicutes to Bacteroidetes. CONCLUSION: The current findings provide multiscale and multifactorial perspectives for understanding the correlations between depression and constipation, and demonstrate new mechanisms of comorbidity of depression and constipation.


Assuntos
Depressão , Microbiota , Ratos , Humanos , Animais , Metaboloma , Metabolômica , Constipação Intestinal
20.
J Am Chem Soc ; 144(31): 14351-14362, 2022 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-35905456

RESUMO

Near-infrared (NIR) fluorophores absorbing maximally in the region beyond 800 nm, i.e., deep-NIR spectral region, are actively sought for biomedical applications. Ideal dyes are bright, nontoxic, photostable, biocompatible, and easily derivatized to introduce functionalities (e.g., for bioconjugation or aqueous solubility). The rational design of such fluorophores remains a major challenge. Silicon-substituted rhodamines have been successful for bioimaging applications in the red spectral region. The longer-wavelength silicon-substituted congeners for the deep-NIR spectral region are unknown to date. We successfully prepared four silicon-substituted bis-benzannulated rhodamine dyes (ESi5a-ESi5d), with an efficient five-step cascade on a gram-scale. Because of the extensive overlapping of their HOMO-LUMO orbitals, ESi5a-ESi5d are highly absorbing (λabs ≈ 865 nm and ε > 105 cm-1 M-1). By restraining both the rotational freedom via annulation and the vibrational freedom via silicon-imparted strain, the fluorochromic scaffold of ESi5 is highly rigid, resulting in an unusually long fluorescence lifetime (τ > 700 ps in CH2Cl2) and a high fluorescence quantum yield (ϕ = 0.14 in CH2Cl2). Their half-lives toward photobleaching are 2 orders of magnitude longer than the current standard (ICG in serum). They are stable in the presence of biorelevant concentration of nucleophiles or reactive oxygen species. They are minimally toxic and readily metabolized. Upon tail vein injection of ESi5a (as an example), the vasculature of a nude mouse was imaged with a high signal-to-background ratio. ESi5 dyes have broad potentials for bioimaging in the deep-NIR spectral region.


Assuntos
Corantes Fluorescentes , Silício , Animais , Fluorescência , Camundongos , Rodaminas
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