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2.
Neurosurg Rev ; 46(1): 288, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37907646

RESUMO

PURPOSE: To identify risk factors for major postoperative complications in meningioma patients and to construct and validate a nomogram that identify patients at high risk of these complications. METHODS: The medical records of meningioma patients who underwent surgical resection in our hospital from January 2018 to December 2020 were collected. The patients were divided into a training set (815 cases from the main campus in 2018 and 2019) and a validation set (300 cases from two other campuses in 2020). Major postoperative complications were defined as any new neurological deficits and complications classified as Clavien-Dindo Grading (CDG) II or higher. Univariate and multivariate analyses were conducted using the training set to identify independent risk factors. A nomogram was constructed based on these results. And then validated the nomogram through bootstrap re-sampling in both the training and validation sets. The concordance index (C-index) and the area under the curve (AUC) were used to assess the discriminative ability of the nomogram. The Hosmer-Lemeshow test was performed to evaluate the goodness-of-fit. The optimal cutoff point for the nomogram was calculated using Youden's index. RESULTS: In the training set, 135 cases (16.56%) experienced major postoperative complications. The independent risk factors identified were male sex, recurrent tumors, American Society of Anesthesiologists (ASA) class III-IV, preoperative Karnofsky Performance Scale (KPS) score < 80, preoperative serum albumin < 35 g/L, tumor in the skull base or central sulcus area, subtotal tumor resection (STR), allogeneic blood transfusion, and larger tumor size. A nomogram was constructed based on these risk factors. It demonstrated good predictive performance, with a C-index of 0.919 for the training set and 0.872 for the validation set. The area under the curve (AUC) > 0.7 indicated satisfactory discriminative ability. The Hosmer-Lemeshow test showed no significant deviation from the predicted probabilities. And the cutoff for nomogram total points was about 200 (specificity 0.881 and sensitivity 0.834). CONCLUSIONS: The constructed nomogram demonstrated robust predictive performance for major postoperative complications in meningioma patients. This model can be used by surgeons as a reference in clinical decision-making.


Assuntos
Neoplasias Meníngeas , Meningioma , Humanos , Masculino , Feminino , Meningioma/cirurgia , Nomogramas , Complicações Pós-Operatórias/epidemiologia , Fatores de Risco , Neoplasias Meníngeas/cirurgia , Estudos Retrospectivos
3.
Angew Chem Int Ed Engl ; 61(43): e202210988, 2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-35979672

RESUMO

Activation of the cyclic GMP-AMP synthase-stimulator of the interferon gene (cGAS-STING) pathway is a potent anticancer immunotherapeutic strategy, and the induction of pyroptosis is a feasible way to stimulate the anticancer immune responses. Herein, two PtII complexes (Pt1 and Pt2) were designed as photoactivators of the cGAS-STING pathway. In response to light irradiation, Pt1 and Pt2 could damage mitochondrial/nuclear DNA and the nuclear envelope to activate the cGAS-STING pathway, and concurrently induce pyroptosis in cancer cells, which evoked an intense anticancer immune response in vitro and in vivo. Overall, we present the first photoactivator of the cGAS-STING pathway, which may provide an innovative design strategy for anticancer immunotherapy.


Assuntos
Neoplasias , Nucleotidiltransferases , Nucleotidiltransferases/metabolismo , Interferons/farmacologia , Platina/farmacologia , Piroptose , Proteínas de Membrana/metabolismo , Transdução de Sinais , Imunoterapia , DNA/metabolismo , Antivirais/farmacologia , Neoplasias/terapia
4.
Chem Sci ; 13(28): 8371-8379, 2022 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-35919711

RESUMO

Thrombin Binding Aptamer (TBA) is a monomolecular well-defined two G-tetrad antiparallel G-quadruplex DNA that inhibits the activity of human α-thrombin. In this report, we synthesized a quasi-cross-shaped platinum(ii) compound (L'2LPt) with one cyclometalated and two carbene ligands. We found L'2LPt has selective affinity to bind the TBA G-quadruplex. A fibrinogen clotting assay revealed that L'2LPt can abrogate the inhibitory activity of TBA against thrombin. We solved the 1 : 1 L'2LPt-TBA complex structure by NMR, which revealed a unique self-adaptive property of L'2LPt upon binding to TBA. In the complex, a carbene ligand of L'2LPt rotates to pair with the cyclometalated ligand to form a plane stacking over half of the TBA G-tetrad and covered by lateral TT loops. It is notable that the heavy atom Pt stays out of the G-tetrad. Meanwhile, the other carbene ligand remains relatively perpendicular and forms a hydrogen bond with a guanine to anchor the L'2LPt position. This structure exhibits a quasi-cross-shaped Pt(ii) compound bound to the G-quadruplex with an unusual "wall-mounted" binding mode. Our structures provide insights into the specific recognition of antiparallel G-quadruplex DNA by a self-adaptive Pt(ii) compound and useful information for the design of selective G-quadruplex targeting non-planar molecules.

5.
Nucleic Acids Res ; 50(14): 7816-7828, 2022 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-35766415

RESUMO

G-quadruplex (G4) transitions play integral roles in regulating biological functions and can be modified by ligands. However, little is known about G4 transitions. Herein, we reveal distinct pathways of a platinum(II) compound Pt-phen converting parallel-stranded MYC G4 to a hybrid-type structure. Three NMR structures, 1:1 5'-end binding, 1:1 3'-end binding and 2:1 Pt-phen-MYC G4 complexes, were determined by NMR. We find that Pt-phen drives G4 transition at a low ratio. Under physiological 100 mM K+ conditions, a significant stable hydrogen-bonded T:T:A triad is formed at 3'-end of hybrid-type Myc1234, and consequently, Pt-phen first binds the 5'-end to form a 1:1 5'-end binding complex and then disrupts the 3' T:T:A triad and binds 3'-end to form a 2:1 complex with more Pt-phen. Remarkably, the G4 transition pathway is different in 5 mM K+ with Pt-phen first binding the 3'-end and then the 5'-end. 'Edgewise-loop and flanking/ligand/G-tetrad' sandwich structure formation and terminal T:T:A triad stabilization play decisive roles in advancing and altering transition pathways. Our work is the first to elucidate the molecular structures of G4 transitions driven by a small molecule. The ligand-driven G4 transition is a dynamic process that includes a quick G4 transition and multiple complexes formation.


Assuntos
Quadruplex G , Compostos de Platina , Ligantes , Espectroscopia de Ressonância Magnética , Estrutura Molecular
6.
Angew Chem Int Ed Engl ; 60(28): 15340-15343, 2021 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-33899272

RESUMO

G-quadruplexes (G4s) are prevalent in oncogenes and are potential antitumor drug targets. However, binding selectivity of compounds to G4s still faces challenges. Herein, we report a platinum(II) complex (Pt1), whose affinity to G4-DNA is activated by adaptive binding and selectivity controlled by binding kinetics. The resolved structure of Pt1/VEGF-G4 (a promoter G4) shows that Pt1 matches 3'-G-tetrad of VEGF-G4 through Cl- -dissociation and loop rearrangement of VEGF-G4. Binding rate constants are determined by coordination bond breakage/formation, correlating fully with affinities. The selective rate-determining binding step, Cl- -dissociation upon G4-binding, is 2-3 orders of magnitude higher than dsDNA. Pt1 potently targets G4 in living cells, effectively represses VEGF expression, and inhibits vascular growth in zebrafish. We show adaptive G4-binding activation and controlled by kinetics, providing a complementary design principle for compounds targeting G4 or similar biomolecules.


Assuntos
Antineoplásicos/farmacologia , Quadruplex G/efeitos dos fármacos , Compostos Organoplatínicos/farmacologia , Antineoplásicos/química , Sítios de Ligação/efeitos dos fármacos , Células HeLa , Humanos , Cinética , Estrutura Molecular , Compostos Organoplatínicos/química
7.
Angew Chem Int Ed Engl ; 59(24): 9719-9726, 2020 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-32173994

RESUMO

G-quadruplex DNA show structural polymorphism, leading to challenges in the use of selective recognition probes for the accurate detection of G-quadruplexes in vivo. Herein, we present a tripodal cationic fluorescent probe, NBTE, which showed distinguishable fluorescence lifetime responses between G-quadruplexes and other DNA topologies, and fluorescence quantum yield (Φf ) enhancement upon G-quadruplex binding. We determined two NBTE-G-quadruplex complex structures with high Φf values by NMR spectroscopy. The structures indicated NBTE interacted with G-quadruplexes using three arms through π-π stacking, differing from that with duplex DNA using two arms, which rationalized the higher Φf values and lifetime response of NBTE upon G-quadruplex binding. Based on photon counts of FLIM, we detected the percentage of G-quadruplex DNA in live cells with NBTE and found G-quadruplex DNA content in cancer cells is 4-fold that in normal cells, suggesting the potential applications of this probe in cancer cell detection.


Assuntos
DNA/química , Quadruplex G , Linhagem Celular Tumoral , DNA/análise , Humanos , Fótons
8.
Ecotoxicol Environ Saf ; 145: 659-664, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28823766

RESUMO

Perfluorinated compounds (PFCs) have received increasing attention worldwide recently because of potential risk to aquatic environment and living organisms. Herein, occurrence and spatial distributions of 17 selected PFCs were investigated in surface water adjacent to potential industrial emission categories in Shanghai. The results showed the distributions of PFCs in the ambient rivers were greatly affected by those industrial sources. Perfluorooctanoic acid (PFOA) and other short-chain PFCs such as perfluoropentanoic acid (PFPeA) and perfluorooctanesulfonate (PFBS) were detected as the predominant species in all samples. Specifically, the total concentrations of PFCs (∑PFCs) near the airport ranged from 142 to 264ngL-1, with PFOA, PFPeA, and PFBS as most prevalent. While near the fluorochemical plant and metal plating, concentrations of ∑PFCs ranged from 200 to 2143ngL-1 and 211ngL-1 to 705ngL-1; and PFOA was the predominant individual PFCs, with the highest concentration of 1985ngL-1. However, concentrations of PFOS were found at relatively low level, which ranged from < 0.06 to 4.44ngL-1. The Spearman correlation analysis of concentration of individual PFCs showed that PFOA and perfluorohexanoic acid (PFHxA) was positive, while the correlation between PFOA and perfluorohexansulfonate (PFHxS) was negative near the airport, indicating PFOA and PFHxA may share common sources. Preliminary ecological risk evaluation of PFCs in adjacent water of the industrial emission areas suggested these emission categories posed higher risks than other area, although the risk level was still relatively safe.


Assuntos
Poluição do Ar , Monitoramento Ambiental/métodos , Fluorocarbonos/análise , Indústrias , Rios/química , Poluentes Químicos da Água/análise , Poluição do Ar/análise , China , Medição de Risco , Abastecimento de Água
9.
Ecotoxicol Environ Saf ; 141: 235-241, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28359989

RESUMO

Benzophenone-type UV filters (BP-UV filters) are frequently introduced into aquatic environment from several sources. The occurrence and fate of select BP-UV filters and their metabolites were investigated in this study. All target compounds were detected in water samples, except for 2, 3, 4-trihydroxybenzophenone (2, 3, 4-OH-BP). The concentration reached up 131ngL-1 for 5-benzoyl-4-hydroxy-2-ethoxybenzenesulfonic acid (BP-4), 30.0ngL-1 for 2-hydroxy-4-methoxybenzophenone (BP-3), and mean value of 158ngL-1 for benzophenone (BP). Concentrations of BP-UV filters were not related to recreational waters but with high population frequencies. In addition, five BP-UV filters, namely 2,2',4,4'-tetrahydroxybenzophenone (BP-2), 2,3,4-OH-BP, 2,4-dihydroxybenzophenone (BP-1), 4-hydroxybenzophenone (4-OH-BP) and BP were investigated for probable sources, and found that they originate from BP-3 metabolism. There is a similar source for BP-3, BP-4, BP-1, 4-OH-BP and BP. Environmental risk assessment (ERA) showed that risk quotients (RQs) of BP-4, BP-3 and BP were 2.7, 0.8 and 0.5, respectively.


Assuntos
Benzofenonas/análise , Rios/química , Protetores Solares/análise , Poluentes Químicos da Água/análise , Benzofenonas/química , Benzofenonas/toxicidade , China , Cromatografia Líquida de Alta Pressão , Ecologia , Medição de Risco , Extração em Fase Sólida , Protetores Solares/química , Protetores Solares/toxicidade , Espectrometria de Massas em Tandem , Poluentes Químicos da Água/química , Poluentes Químicos da Água/toxicidade
10.
Zhonghua Nan Ke Xue ; 20(2): 106-10, 2014 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-24520659

RESUMO

OBJECTIVE: To establish an effective method for haploid spermatid enrichment by Hoechst 33342 staining and flow sorting. METHODS: Mouse testicular monoplast suspension was prepared by two-step enzyme digestion, and the cells were incubated in the medium containing Hoechst 33342 and Verapamil. Haploid spermatids were separated and enriched according to their DNA content by flow sorting. The gene expressions in the spermatids of several histone-modified enzymes, including the histone acetylases (HAT) and histone deacetylases (HDAC), were examined by RT-PCR and compared with that in the HAT-inhibitor curcumin-treated counterparts. RESULTS: We successfully enriched the haploid spermatids with high purity and further purified the round and elongated spermatids. RT-PCR results indicated the specificity of the expression of the HAT gene in the spermatids, and that it was influenced by curcumin. CONCLUSION: Flow sorting can efficiently improve the purity of haploid spermatid enrichment, which helps a lot to elucidate the mechanisms of spermiogenesis.


Assuntos
Separação Celular/métodos , Citometria de Fluxo/métodos , Espermátides/citologia , Animais , Haploidia , Masculino , Camundongos , Camundongos Endogâmicos ICR
11.
Asian J Androl ; 16(2): 309-13, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24457839

RESUMO

Bactericidal/permeability-increasing protein (BPI) is an endogenous antibiotic protein with activity against gram-negative bacteria. In the present study, we examined the expression of BPI in postnatal mouse testes and epididymides as well as the subcellular localization within epididymal spermatozoa. Our results showed that, BPI mRNA was expressed in testis and epididymis independently. Throughout the epididymis, the BPI protein level gradually decreased in the epididymal epithelium in a spatial manner, specialized within the cytoplasm of clear cells in the cauda part. We detected BPI proteins in intact acrosome, implying its testicular origin; on the other hand, after the acrosome reaction, BPI proteins were observed dispersed across the entire sperm head, especially enriched at the equatorial segment. Our findings suggested a dual origin of the BPI that generated both in the testis and epididymis, and associated with mouse spermatozoa. BPI protein might be involved in the dynamics modification of the sperm plasma membrane and also the fertilization process.


Assuntos
Peptídeos Catiônicos Antimicrobianos/metabolismo , Proteínas Sanguíneas/metabolismo , Epididimo/metabolismo , Espermatozoides/metabolismo , Testículo/metabolismo , Animais , Sequência de Bases , Primers do DNA , Masculino , Camundongos
12.
Biomed Environ Sci ; 26(1): 40-7, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23294614

RESUMO

OBJECTIVE: To assess and compare the Human Papillomavirus (HPV) detection efficiency and the potential clinical utility of PCR sequencing-based technology. METHODS: Four HPV consensus primer sets (GP5+/6+, MGP, MY09/11, and PGMY09/11) were used in order to amplify a broad spectrum of HPV types for HPV infection in 325 cervical samples and the PCR products were sequenced afterwards for the HPV genotyping. RESULTS: The HPV-positive rate was 75.4%, of which 35.5% harbored more than one HPV genotype. A total of 36 different genotypes was found, with HPV 16 (24.1%) being the most prevalent, followed by HPV 58 (13.3%) and HPV 52 (9.6%). There were substantial to almost perfect agreements between different primer sets regarding HPV detection efficiency, with the kappa value varying from 0.751 to 0.925, MGP, and PGMY09/11 were the most effective in detecting multiple infections (P < 0.001). With each of the primer sets, a board range of HPV types could be identified, though there were several differences for a few genotypes. CONCLUSION: The substantial agreement between PCR-sequencing and HC2 for the detection of high-risk HPV (kappa=0.761) indicated that PCR-sequencing is also suitable for routine HPV screening.


Assuntos
Alphapapillomavirus/genética , Alphapapillomavirus/isolamento & purificação , Infecções por Papillomavirus/virologia , Reação em Cadeia da Polimerase/métodos , Adulto , Idoso , Feminino , Genótipo , Humanos , Pessoa de Meia-Idade , Adulto Jovem
13.
Zhonghua Nan Ke Xue ; 15(8): 703-7, 2009 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-19852270

RESUMO

OBJECTIVE: To establish a stable recipient mouse model for stem cell transplantation into seminiferous tubules and improve the traditional techniques for transplantation. METHODS: Sixty male ICR mice were equally divided into Groups A, B, C and D, and injected with Busulfan at 15 mg/kg, 30 mg/kg, 40 mg/kg and 0 mg/kg, respectively. The survival rate was recorded every day, and the testis weight and spermatogenesis of testicular tubules were determined at 4, 8 and 12 weeks after the injection. We improved the stem cell transplantation technique and designed a new transplantation device, which connected the nozzle end, syringe and puncture needle by a three-way joint. The nozzle end was used for tentative injection, and the syringe for drawing and then injecting the cell suspension. RESULTS: Only one mouse in Group C died after the injection. At 4 weeks after Busulfan treatment, the testis weight decreased apparently in Groups A, B and C, with significant differences from D (P < 0.05). The differences remained significant at 8 weeks (P < 0.05), except between Groups A and D (P > 0.05), but at 12 weeks none of the first three groups showed any significant difference from Group D (P > 0.05). At 4 and 8 weeks, the rate of hollow seminiferous tubules was < 50% in Group A and > 50% in Groups B and C, and almost returned to normal at 12 weeks, with no significant differences among the three groups (P > 0.05), but it remained unchanged in Group D. The improved transplantation device increased the success rate (> 90%), lowered the donor cell loss (< 50 microl cell suspension needed for both testes) and shortened the process ( < 10 min for one testis). CONCLUSION: Intraperitoneal injection of Busulfan at 30 mg/kg is suitable for the establishment of the recipient mouse model of stem cell transplantation. The improved transplantation device and methods help promote the efficiency and success rate of the transplantation operation.


Assuntos
Modelos Animais de Doenças , Túbulos Seminíferos/citologia , Transplante de Células-Tronco/métodos , Testículo , Animais , Masculino , Camundongos , Camundongos Endogâmicos ICR
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