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1.
Microbiol Res ; 282: 127668, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38430889

RESUMO

Immune checkpoint inhibitor (ICI) therapies, such as those blocking the interaction of PD-1 with its ligands, can restore the immune-killing function of T cells. However, ICI therapy is clinically beneficial in only a small number of patients, and it is difficult to predict post-treatment outcomes, thereby limiting its widespread clinical use. Research suggests that gut microbiota can regulate the host immune system and affect cancer progression and treatment. Moreover, the effectiveness of immunotherapy is related to the composition of the patient's gut microbiota; different gut microbial strains can either activate or inhibit the immune response. However, the importance of the microbial composition within the tumor has not been explored until recently. This study describes recent advances in the crosstalk between microbes in tumors and gut microbiota, which can modulate the tumor microbiome by directly translocating into the tumor and altering the tumor microenvironment. This study focused on the potential manipulation of the tumor and gut microbiota using fecal microbiota transplantation (FMT), probiotics, antimicrobials, prebiotics, and postbiotics to enrich immune-boosting bacteria while decreasing unfavorable bacteria to proactively improve the efficacy of ICI treatments. In addition, the use of genetic technologies and nanomaterials to modify microorganisms can largely optimize tumor immunotherapy and advance personalized and precise cancer treatment.


Assuntos
Microbioma Gastrointestinal , Microbiota , Neoplasias , Humanos , Inibidores de Checkpoint Imunológico/uso terapêutico , Clonagem Molecular , Neoplasias/terapia , Microambiente Tumoral
2.
Biotechnol Biofuels Bioprod ; 16(1): 157, 2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37876019

RESUMO

BACKGROUND: ß-Alanine is a precursor of many important pharmaceutical products and food additives, its market demand is continuously increasing nowadays. Whole-cell catalysis relying on the recombinant expression of key ß-alanine synthesizing enzymes is an important method to produce ß-alanine. Nevertheless, ß-alanine synthesizing enzymes found so far have problems including easy inactivation, low expression or poor catalytic activity, and it remains necessary to develop new enzymes. RESULTS: Herein, we characterized an L-aspartate-α-decarboxylase, MpADC, from an aphid, Myzus persicae. It showed excellent catalytic activity at pH 6.0-7.5 and 37 °C. With the help of chaperone co-expression and N-terminal engineering guided by AlphaFold2 structure prediction, the expression and catalytic ability of MpADC in Escherichia coli were significantly improved. Using 50 g/L of E. coli cells expressing the MpADC-∆39 variant cultured in a 15-L fermenter, 232.36 g/L of ß-alanine was synthesized in 13.5 h, with the average ß-alanine yield of 17.22 g/L/h, which is best known so far. CONCLUSIONS: Our research should facilitate the production of ß-alanine in an environment-friendly manner.

3.
J Inflamm (Lond) ; 20(1): 23, 2023 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-37430327

RESUMO

BACKGROUND: To compare the severity of radiation-induced lung injury (RILI) after the right lung of SD rats received interstitial brachytherapy and stereotactic radiotherapy (SBRT). METHODS: RILI rat model was established using interstitial brachytherapy and SBRT methods, respectively. CT scan was performed to analyze the lung volume and the CT value difference between the left and right lungs in rats. Then the lung tissues were analyzed through H&E staining, peripheral blood was extracted to detect the expression levels of serum inflammatory cytokines, pro-fibrotic cytokines, and fibrotic-inhibiting cytokines by ELISA. RESULTS: The difference between right and left lung CT values was significantly elevated in the SBRT group when compared with the control group and the interstitial brachytherapy group (P < 0.05). The IFN-γ expression in the interstitial brachytherapy group was significantly different from that in the SBRT group at week 1, 4, 8 and 16. Besides, the expressions of IL-2, IL-6 and IL-10 in SBRT group were significantly higher than that of interstitial brachytherapy group (P < 0.05). The TGF-ß expression in interstitial brachytherapy group reached its peak with the increase of time from week 1 to week 16, and it was significantly lower than SBRT group (P < 0.05). The mortality rate in the SBRT group was 16.7%, which was significantly higher than that in the interstitial brachytherapy group. CONCLUSION: The treatment method of interstitial brachytherapy is considered as an effective and safe tool by reducing the side effects of radiotherapy and increasing the radiation dose of radiotherapy.

4.
Open Med (Wars) ; 18(1): 20230672, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36941992

RESUMO

Neuroblastoma (NB) is a common childhood cancer. Circular RNA RAN binding protein 17 (circRANBP17) has been identified to participate in diverse tumor progression. This study aims to explore the function and mechanism of circRANBP17 in NB. The levels of circRANBP17, miR-27b-3p and KDM1A in NB tissues and cells were measured by qRT-PCR. Mouse model assay was performed to investigate the effect of circRANBP17 knockdown on tumor formation in vivo. The levels of circRANBP17 and KDM1A were significantly up-regulated, and the level of miR-27b-3p was strikingly down-regulated in NB tissues and cells (SK-N-SH and SK-N-AS). Functional studies indicated that miR-27b-3p inhibitor mitigated the inhibitory effects on cell proliferation, migration, invasion and the promoting effect on cell apoptosis in SK-N-SH and SK-N-AS cells induced by circRANBP17 knockdown. Also, miR-27b-3p regulated NB cell malignancy by targeting KDM1A. Further studies revealed that miR-27b-3p inhibitor reversed the low expression of KDM1A induced by circRANBP17 knockdown. In support, circRANBP17 knockdown led to inhibition of tumor formation in vivo. In conclusion, circRANBP17 modulated KDM1A to promote cell proliferation, migration, invasion and restrain cell apoptosis in NB by sponging miR-27b-3p, and the new regulatory network may provide a theoretical basis for the further study of NB.

5.
J Nurs Manag ; 30(7): 3330-3339, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36042016

RESUMO

AIMS: To explore whether perceived overqualification increases the risk of burnout and whether transformational leadership negatively moderates this relationship. BACKGROUND: Perceived overqualification might contribute to burnout and lead to poor experience of transformational leadership, and transformational leadership might be associated with burnout. However, these relationships have not yet been confirmed. METHODS: A multicentre cross-sectional study. A total of 321 nurses from intensive care units were recruited from six tertiary hospitals. Scale of Perceived OverQualification, Transformational Leadership Questionnaire and emotional exhaustion subscale of the Maslach Burnout Inventory-General Survey were employed to collect the data. Hierarchical multiple regression and bootstrap resampling were applied to analyse the data. RESULTS: Burnout was positively associated with perceived overqualification and negatively associated with transformational leadership (each p < 0.05). Transformational leadership significantly mediated the relationship between perceived overqualification and burnout (b = -0.6389, 95% confidence interval: -0.8706, -0.4072). CONCLUSION: Our findings indicated that perceived overqualification and transformational leadership directly or indirectly affect burnout among nurses from intensive care units. IMPLICATIONS FOR NURSING MANAGERS: Personal and organizational-oriented interventions utilizing nurses' overall qualifications and implementing transformational leadership should be employed by nurse managers to alleviate burnout and promote the work performance of nurses from intensive care units.


Assuntos
Esgotamento Profissional , Recursos Humanos de Enfermagem Hospitalar , Humanos , Liderança , Estudos Transversais , Esgotamento Profissional/etiologia , Esgotamento Profissional/psicologia , Inquéritos e Questionários , Unidades de Terapia Intensiva , Recursos Humanos de Enfermagem Hospitalar/psicologia
6.
Front Oncol ; 11: 731503, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34557414

RESUMO

The hypoxic state in a solid tumor refers to the internal hypoxic environment that appears as the tumor volume increases (the maximum radius exceeds 180-200 microns). This state can promote angiogenesis, destroy the balance of the cell's internal environment, and lead to resistance to radiotherapy and chemotherapy, as well as poor prognostic factors such as metastasis and recurrence. Therefore, accurate quantification, mapping, and monitoring of hypoxia, targeted therapy, and improvement of tumor hypoxia are of great significance for tumor treatment and improving patient survival. Despite many years of development, PET-based hypoxia imaging is still the most widely used evaluation method. This article provides a comprehensive overview of tumor hypoxia imaging using radionuclide-labeled PET tracers. We introduced the mechanism of tumor hypoxia and the reasons leading to the poor prognosis, and more comprehensively included the past, recent and ongoing studies of PET radiotracers for tumor hypoxia imaging. At the same time, the advantages and disadvantages of mainstream methods for detecting tumor hypoxia are summarized.

7.
Kidney Blood Press Res ; 41(6): 956-965, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27924804

RESUMO

BACKGROUND/AIMS: This study explored the correlation between hypertension and non-muscle myosin heavy chain 9 (MYH9) gene polymorphisms in Chinese chronic kidney disease (CKD) patients. METHODS: This case-control study included 301 patients with CKD and 293 healthy controls. The E1 haplotype single nucleotide polymorphisms (SNPs) rs3752462 and rs4821480 were genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis. The association between MYH9 polymorphisms and high systolic blood pressure (SBP ≥ 140 mmHg) susceptibility in CKD patients was analysed. RESULTS: The cases and controls had similar genotype and allele distributions at rs3752462 and rs4821480. No GG genotype at rs4821480 was observed. Patients with SBP < 140 mmHg were more likely to have the CC genotype (17.1%) than patients with SBP ≥ 140 mmHg (4.3%) (P = 0.001). Creatinine clearance (OR = 0.99, 95% CI = 0.98-0.10, P = 0.01) was associated with SBP in patients with CKD. The risk of SBP ≥ 140 mmHg was 0.24-fold greater among patients with the CC genotype than among patients with the TT genotype (P = 0.002). CONCLUSION: The rs3752462 polymorphism of MYH9 is associated with SBP in patients with CKD. The T allele in the dominant model was associated with an elevated risk for high SBP.


Assuntos
Hipertensão/genética , Proteínas Motores Moleculares/genética , Cadeias Pesadas de Miosina/genética , Polimorfismo de Nucleotídeo Único , Insuficiência Renal Crônica/genética , Adolescente , Adulto , Idoso , Povo Asiático/genética , Estudos de Casos e Controles , Criança , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
8.
Magn Reson Chem ; 51(9): 517-22, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23788325

RESUMO

Unambiguous structural elucidation of active pharmaceutical ingredients (API) impurities is a particularly challenging necessity of pharmaceutical development, particularly if the impurities are low level (0.1% level). In many cases, this requires acquiring high-quality NMR data on a pure sample of each impurity. High-quality, high signal-to-noise (S/N) one- and two-dimensional NMR data can be obtained using liquid chromatography-solid phase extraction-cryoflow NMR (LC-SPE-cryoflow NMR) with a combination of semi-preparative column for separation and mother liquor as a source of concentrated impurities. These NMR data, in conjunction with mass spectrometry data, allowed for quick and unambiguous structural elucidations of four impurities found at low level in the crystallized API but found at appreciable levels in the mother liquor that was used as the source for these impurities. These data show that semi-preparative columns can be used at lower than ideal flow rates to facilitate trapping of HPLC components for LC-SPE-cryoflow NMR analysis without compromising chromatographic resolution. Also, despite the complex chromatography encountered with the use of mother liquor as a source of impurities, acceptably pure analytes were obtained for acquiring NMR data for unambiguous structure elucidations.


Assuntos
Contaminação de Medicamentos , Extração em Fase Sólida , Cromatografia Líquida , Espectroscopia de Ressonância Magnética/normas , Estrutura Molecular , Padrões de Referência
9.
J Med Chem ; 51(6): 1976-80, 2008 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-18288793

RESUMO

A series of amino acid ester prodrugs of the dual VEGFR-2/FGFR-1 kinase inhibitor 1 (BMS-540215) was prepared in an effort to improve the aqueous solubility and oral bioavailability of the parent compound. These prodrugs were evaluated for their ability to liberate parent drug 1 in in vitro and in vivo systems. The l-alanine prodrug 8 (also known as brivanib alaninate/BMS-582664) was selected as a development candidate and is presently in phase II clinical trials.


Assuntos
Carcinoma/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Pró-Fármacos/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Pirróis/farmacologia , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/antagonistas & inibidores , Triazinas/farmacologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Administração Oral , Alanina/análogos & derivados , Animais , Disponibilidade Biológica , Proliferação de Células/efeitos dos fármacos , Ensaios Clínicos Fase II como Assunto , Desenho de Fármacos , Avaliação Pré-Clínica de Medicamentos , Humanos , Intestinos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Camundongos , Microssomos/efeitos dos fármacos , Estrutura Molecular , Pró-Fármacos/síntese química , Pró-Fármacos/química , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Pirróis/síntese química , Pirróis/química , Solubilidade , Estereoisomerismo , Triazinas/síntese química , Triazinas/química , Água/química , Ensaios Antitumorais Modelo de Xenoenxerto
10.
J Med Chem ; 47(15): 3843-52, 2004 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-15239662

RESUMO

A series of sulfonyl-group containing analogues of aldophosphamide (Aldo) were synthesized as potential anticancer prodrugs that liberate the cytotoxic phosphoramide mustards (PM, IPM, and tetrakis-PM) via beta-elimination, a nonenzymatic activation mechanism. Kinetic studies demonstrated that all these compounds spontaneously liberate phosphoramide mustards with half-lives in the range of 0.08-15.2 h under model physiological conditions in 0.08 M phosphate buffer at pH 7.4 and 37 degrees C. Analogous to Aldo, the rates of beta-elimination in all compounds was enhanced in reconstituted human plasma under same conditions. The compounds were more potent than the corresponding phosphoramide mustards against V-79 Chinese hamster lung fibroblasts in vitro (IC(50) = 1.8-69.1 microM). Several compounds showed excellent in vivo antitumor activity in CD2F1 mice against both P388/0 (Wild) and P388/CPA (CP-resistant) tumor cell lines.


Assuntos
Antineoplásicos/síntese química , Ciclofosfamida/farmacologia , Mostardas de Fosforamida/síntese química , Pró-Fármacos/síntese química , Sulfonas/síntese química , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Cricetinae , Resistencia a Medicamentos Antineoplásicos , Ensaios de Seleção de Medicamentos Antitumorais , Estabilidade de Medicamentos , Meia-Vida , Humanos , Camundongos , Mostardas de Fosforamida/química , Mostardas de Fosforamida/farmacologia , Pró-Fármacos/química , Pró-Fármacos/farmacologia , Relação Estrutura-Atividade , Sulfonas/química , Sulfonas/farmacologia , Transplante Heterólogo
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