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1.
Angew Chem Int Ed Engl ; 63(16): e202317695, 2024 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-38380831

RESUMO

3D electron diffraction (3D ED) has shown great potential in crystal structure determination in materials, small organic molecules, and macromolecules. In this work, an automated, low-dose and low-bias 3D ED protocol has been implemented to identify six phases from a multiple-phase melt-crystallisation product of an active pharmaceutical ingredient, griseofulvin (GSF). Batch data collection under low-dose conditions using a widely available commercial software was combined with automated data analysis to collect and process over 230 datasets in three days. Accurate unit cell parameters obtained from 3D ED data allowed direct phase identification of GSF Forms III, I and the known GSF inclusion complex (IC) with polyethylene glycol (PEG) (GSF-PEG IC-I), as well as three minor phases, namely GSF Forms II, V and an elusive new phase, GSF-PEG IC-II. Their structures were then directly determined by 3D ED. Furthermore, we reveal how the stabilities of the two GSF-PEG IC polymorphs are closely related to their crystal structures. These results demonstrate the power of automated 3D ED for accurate phase identification and direct structure determination of complex, beam-sensitive crystallisation products, which is significant for drug development where solid form screening is crucial for the overall efficacy of the drug product.


Assuntos
Elétrons , Polímeros , Polímeros/química , Griseofulvina/química , Polietilenoglicóis/química , Cristalização/métodos
2.
BMC Med ; 21(1): 464, 2023 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-38012705

RESUMO

BACKGROUND: Post-radiation nasopharyngeal necrosis (PRNN) is a severe adverse event following re-radiotherapy for patients with locally recurrent nasopharyngeal carcinoma (LRNPC) and associated with decreased survival. Biological heterogeneity in recurrent tumors contributes to the different risks of PRNN. Radiomics can be used to mine high-throughput non-invasive image features to predict clinical outcomes and capture underlying biological functions. We aimed to develop a radiogenomic signature for the pre-treatment prediction of PRNN to guide re-radiotherapy in patients with LRNPC. METHODS: This multicenter study included 761 re-irradiated patients with LRNPC at four centers in NPC endemic area and divided them into training, internal validation, and external validation cohorts. We built a machine learning (random forest) radiomic signature based on the pre-treatment multiparametric magnetic resonance images for predicting PRNN following re-radiotherapy. We comprehensively assessed the performance of the radiomic signature. Transcriptomic sequencing and gene set enrichment analyses were conducted to identify the associated biological processes. RESULTS: The radiomic signature showed discrimination of 1-year PRNN in the training, internal validation, and external validation cohorts (area under the curve (AUC) 0.713-0.756). Stratified by a cutoff score of 0.735, patients with high-risk signature had higher incidences of PRNN than patients with low-risk signature (1-year PRNN rates 42.2-62.5% vs. 16.3-18.8%, P < 0.001). The signature significantly outperformed the clinical model (P < 0.05) and was generalizable across different centers, imaging parameters, and patient subgroups. The radiomic signature had prognostic value concerning its correlation with PRNN-related deaths (hazard ratio (HR) 3.07-6.75, P < 0.001) and all causes of deaths (HR 1.53-2.30, P < 0.01). Radiogenomics analyses revealed associations between the radiomic signature and signaling pathways involved in tissue fibrosis and vascularity. CONCLUSIONS: We present a radiomic signature for the individualized risk assessment of PRNN following re-radiotherapy, which may serve as a noninvasive radio-biomarker of radiation injury-associated processes and a useful clinical tool to personalize treatment recommendations for patients with LANPC.


Assuntos
Neoplasias Nasofaríngeas , Recidiva Local de Neoplasia , Humanos , Carcinoma Nasofaríngeo/genética , Estudos Retrospectivos , Recidiva Local de Neoplasia/diagnóstico por imagem , Recidiva Local de Neoplasia/genética , Prognóstico , Neoplasias Nasofaríngeas/diagnóstico por imagem , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/radioterapia , Imageamento por Ressonância Magnética/métodos
3.
Mol Pharm ; 20(8): 3854-3863, 2023 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-37450774

RESUMO

Identification of a thermodynamically stable polymorph is an important step in the early stage of drug development. Ritonavir (RIT) is a well-known case where the most stable polymorph II emerged after being marketed, leading to a loss of $250 million. Herein, we report the findings that routine melt crystallization can reveal the late-appearing polymorph II of RIT at small supercooling, but the probability of nucleation is very low. The addition of 30-50% polyethylene glycol (PEG) promotes the crystallization of Form II as the only phase at low supercooling, making it easier to detect in polymorphism screening. During the course of our research, a new polymorph, denoted Form III, was unexpectedly discovered, crystallizing as the major phase from neat RIT melts. Single crystals of Form III were grown from melt microdroplets. Benefiting from the ability of synchrotron radiation to detect weak diffraction signals that cannot be accessible by a laboratory diffractometer, a reasonable structure of Form III was solved with slight disorder relative to thiazole groups (P1 space group and Z' = 4). The thermodynamic stability ranking of the three true polymorphs is Form II > Form I > Form III, as opposed to the order of solubility. The capacity to efficiently reveal rich polymorphs, especially the kinetically hindered polymorph, and rapidly grow single crystals of a new phase for structure determination together highlights the necessity of incorporating melt crystallization into routine methods for pharmaceutical polymorphism screening.


Assuntos
Polietilenoglicóis , Ritonavir , Cristalização , Termodinâmica
4.
Acta Pharmacol Sin ; 43(5): 1200-1209, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35165400

RESUMO

Nonalcoholic steatohepatitis (NASH) is increasingly recognized as a serious disease that can lead to cirrhosis, hepatocellular carcinoma (HCC), and death. However, there is no effective drug to thwart the progression of the disease. Development of new drugs for NASH is an urgent clinical need. Liver biopsy plays a key role in the development of new NASH drugs. Histological findings based on liver biopsy are currently used as the main inclusion criteria and the primary therapeutic endpoint in NASH clinical trials. However, there are inherent challenges in the use of liver biopsy in clinical trials, such as evaluation reliability, sampling error, and invasive nature of the procedure. In this article, we review the advantages and value of liver histopathology based on liver biopsy in clinical trials of new NASH drugs. We also discuss the challenges and limitations of liver biopsy and identify future drug development directions.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Hepatopatia Gordurosa não Alcoólica , Biópsia , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Desenvolvimento de Medicamentos , Humanos , Fígado/patologia , Cirrose Hepática/patologia , Neoplasias Hepáticas/patologia , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/patologia , Reprodutibilidade dos Testes
5.
J Clin Lab Anal ; 36(2): e24200, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34957609

RESUMO

BACKGROUND: The roles of PD-1+ CXCR5+ follicular helper CD8+ T cell were reported in different disease conditions, but their roles in transplantation are unclear. In this study, the association between PD-1+ CXCR5+ follicular helper CD8+ T cell and renal allograft dysfunction in kidney transplant recipients (KTRs) was investigated. METHODS: 82 KTRs were enrolled in this study. 45 KTRs were included in the chronic allograft dysfunction (CAD) group, and 37 KTRs were included in the stable recipients group. Among the CAD group, 12 cases of antibody-mediated rejection (ABMR) and 4 cases of T cell-mediated rejection (TCMR) were diagnosed by biopsy. The percentage of CXCR5+ CD8+ T cells and the co-expression of signal transducers and activators of transcription 4 (STAT4), STAT5, and PD-1 in peripheral blood were determined by flow cytometry. RESULTS: The expression of CXCR5 on CD3+ CD8+ T cells and the percentage of STAT5+ CXCR5+ cells in the CD3+ CD8+ T-cell population were significantly lower in the CAD group (p < 0.05), while the expression of PD-1+ CXCR5+ CD8+ T cells was significantly higher (p < 0.05). Through logistic regression analysis, we concluded that the percentage of PD-1+ CXCR5+ CD8+ T cells was an independent risk factor for renal dysfunction. Grouping by pathological type, PD-1+ CXCR5+ CD8+ T cells showed relatively good diagnostic efficacy for ABMR by ROC analysis. CONCLUSIONS: Our results suggested that PD-1+ CXCR5+ CD8+ T cells were a promising biomarker for distinguishing renal allograft dysfunction and different allograft pathological types. Also, our findings may provide new ways of identifying and treating allograft rejection.


Assuntos
Transplante de Rim , Rim/fisiopatologia , Receptor de Morte Celular Programada 1/metabolismo , Células T Auxiliares Foliculares/fisiologia , Adulto , Aloenxertos , Biomarcadores , Linfócitos T CD8-Positivos/fisiologia , Feminino , Rejeição de Enxerto/diagnóstico , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Receptor de Morte Celular Programada 1/fisiologia , Curva ROC , Receptores CXCR5/metabolismo , Células T Auxiliares Foliculares/metabolismo
6.
Angew Chem Int Ed Engl ; 61(7): e202114985, 2022 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-34902212

RESUMO

Indomethacin is a clinically classical non-steroidal anti-inflammatory drug that has been marketed since 1965. The third polymorph, Form δ, was discovered by both melt and solution crystallization in 1974. δ-indomethacin cannot be cultivated as large single crystals suitable for X-ray crystallography and, therefore, its crystal structure has not yet been determined. Here, we report the structure elucidation of δ-indomethacin by 3D electron diffraction and reveal the truth that melt-crystallized and solution-crystallized δ-indomethacin are in fact two polymorphs with different crystal structures. We propose to keep the solution-crystallized polymorph as Form δ and name the melt-crystallized polymorph as Form θ. Intriguingly, both structures display plastic flexibility based on a slippage mechanism, making indomethacin the first drug to have two plastic polymorphs. This discovery and correction of a 47-year-old misunderstanding signify that 3D electron diffraction has become a powerful tool for polymorphic structural studies.


Assuntos
Anti-Inflamatórios não Esteroides/química , Indometacina/química , Cristalografia por Raios X , Modelos Moleculares , Estrutura Molecular
7.
Zhongguo Zhong Yao Za Zhi ; 46(16): 4117-4123, 2021 Aug.
Artigo em Zh | MEDLINE | ID: mdl-34467722

RESUMO

This study aims to explore the relationship of DNA methylation with the contents of the index components as well as the growth and development of Pogostemon cablin. The demethylation reagent 5-azacytidine(5-azaC) was used to treat the tissue culture seedlings of patchouliol-type P. cablin. High performance liquid chromatography was employed to evaluate the changes of DNA methy-lation in P. cablin, and GC-MS to detect the contents of index components in P.cablin. The agronomic characters of P.cablin were measured using the common methods. The results showcased that DNA methylation of P.cablin was significantly reduced by 5-azaC in a concentration-dependent manner. Thirty days after treatment with 5-azaC at different concentrations, the content of patchouli alcohol changed slightly; compared with that in the control group, the content of pogostone in 50 µmol·L~(-1) and 100 µmol·L~(-1) 5-azaC groups was significantly up-regulated. The 100 µmol·L~(-1) 5-azaC group had the largest differences in contents of pogostone and patchouli alcohol compared with the control group, followed by the 50 µmol·L~(-1) 5-azaC group. Ninety days after disinhibition, the content of pogostone in the treatment group was significantly increased and the content of patchouli alcohol was significantly decreased. In addition, 5-azaC significantly inhibited the growth and development of P.cablin in a dose-dependent manner. These results indicate that DNA methylation regulates the biosynthesis of the index components in patchouliol-type P.cablin and proper demethylation can directly promote the synthesis of pogostone and indirectly affect the accumulation of patchouli alcohol.


Assuntos
Pogostemon , Azacitidina , Metilação de DNA , Cromatografia Gasosa-Espectrometria de Massas , Óleos Voláteis , Pogostemon/genética
8.
J Phys Chem A ; 124(24): 5033-5041, 2020 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-32436382

RESUMO

To provide feasible methods for the extraction of valuable metals from spent batteries or low-grade primary ores, the extraction behavior of some representative acidic phosphorus-containing compounds (APCCs) as extractants is evaluated from the perspective of experimental and theoretical investigations in this work. Aqueous solutions containing five metal ions, Ca(II), Co(II), Mg(II), Mn(II), and Ni(II), were made to simulate leaching liquids, and the extraction of these metals was investigated. A simplified calculated model was used to evaluate the interaction between each extractant and metal ions. The calculation results agree well with the experimental tests in trend. This work not only provides potential extractants for the extraction of valuable metals from spent batteries or low-grade primary ores but also demonstrates the practicability of the simplified calculation model.

9.
J Clin Lab Anal ; 34(9): e23373, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32844458

RESUMO

BACKGROUND: Red blood cell distribution width (RDW) has been validated valuable in predicting outcome and acute kidney injury (AKI) in several clinical settings. The aim of this study was to explore whether RDW is associated with outcome and AKI in patients with traumatic brain injury (TBI). METHODS: Patients admitted to our hospital for TBI from January 2015 to August 2018 were included in this study. Multivariate logistic regression analysis was performed to identify risk factors of AKI and outcome in patients with TBI. The value of RDW in predicting AKI and outcome was evaluated by receiver operating characteristic (ROC) curve. RESULTS: Three hundred and eighteen patients were included in this study. The median of RDW was 14.25%. We divided subjects into two groups based on the median and compared difference of variables between two groups. The incidence of AKI and mortality was higher in high RDW (RDW > 14.25) group (31.45% vs 9.43%, P < .001; 69.81% vs 29.56%, P < .001). Spearman's method showed RDW was moderately associated with 90-day Glasgow Outcome Scale (GOS) (P < .001). In multivariate logistic regression analysis, RDW, lymphocyte, chlorine, and serum creatinine were risk factors of AKI. And Glasgow Coma Scale (GCS), glucose, chlorine, AKI, and RDW were risk factors of mortality. The area under the ROC curve (AUC) of RDW for predicting AKI and mortality was 0.724 (0.662-0.786) and 0.754 (0.701-0.807), respectively. Patients with higher RDW were likely to have shorter median survival time (58 vs 70, P < .001). CONCLUSIONS: Red blood cell distribution width is an independent risk factor of AKI and mortality in patients with TBI.


Assuntos
Injúria Renal Aguda/epidemiologia , Injúria Renal Aguda/mortalidade , Biomarcadores/sangue , Lesões Encefálicas Traumáticas/fisiopatologia , Índices de Eritrócitos , Injúria Renal Aguda/sangue , Injúria Renal Aguda/patologia , Adulto , China/epidemiologia , Feminino , Seguimentos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Prognóstico , Curva ROC , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida
10.
Hell J Nucl Med ; 23(1): 88-89, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32222736

RESUMO

We present a case of synchronous bilateral renal cell carcinoma and prostate carcinoma in a 62 year old man. In a fluorine-18-fluorodeoxyglucose positron emission tomography (18F-FDG PET) scan, the left renal mass showed intense 18F-FDG uptake with maximum standardized uptake volume (SUVmax) of 8.12, while uptake in the right renal mass was minimal with SUVmax of 2.99. Fluorine-18-FDG uptake in the prostate gland lesion was moderate with SUVmax of 4.19. Histopathologically, both renal tumors were clear cell renal cell carcinoma with International Society of Urological Pathology (ISUP) Grade 2 and 3 for the right and left kidney, respectively and prostate gland lesion was typical prostate gland carcinoma.


Assuntos
Carcinoma de Células Renais/diagnóstico por imagem , Fluordesoxiglucose F18 , Neoplasias Renais/diagnóstico por imagem , Segunda Neoplasia Primária/diagnóstico por imagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias da Próstata/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade
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