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1.
Clin Transplant ; 38(7): e15396, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38967600

RESUMO

INTRODUCTION: Central nervous system leukemia (CNSL) remains a serious complication in patients with acute myeloid leukemia (AML) and an ambiguous prognostic factor for those receiving allo-geneic hematopoiesis stem cell transplantation (allo-HSCT). It is unknown whether using more sensitive tools, such as multiparameter flow cytometry (MFC), to detect blasts in the cerebrospinal fluid (CSF) would have an impact on outcome. METHODS: We retrospectively analyzed the clinical outcomes of 1472 AML patients with or without cytology or MFC positivity in the CSF before transplantation. Abnormal CSF (CSF+) was detected via conventional cytology and MFC in 44 patients at any time after diagnosis. A control group of 175 CSF-normal (CSF-) patients was generated via propensity score matching (PSM) analyses according to sex, age at transplant, and white blood cell count at diagnosis. RESULTS: Compared to those in the CSF-negative group, the conventional cytology positive and MFC+ groups had comparable 8-year nonrelapse mortality (NRM) (4%, 4%, and 6%, p = 0.82), higher cumulative incidence of relapse (CIR) (14%, 31%, and 32%, p = 0.007), lower leukemia-free survival (LFS) (79%, 63%, and 64%, p = 0.024), and overall survival (OS) (83%, 63%, and 68%, p = 0.021), with no significant differences between the conventional cytology positive and MFC+ groups. Furthermore, multivariate analysis confirmed that CSF involvement was an independent factor affecting OS and LFS. CONCLUSION: Our results indicate that pretransplant CSF abnormalities are adverse factors independently affecting OS and LFS after allotransplantation in AML patients.


Assuntos
Citometria de Fluxo , Transplante de Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda , Transplante Homólogo , Humanos , Feminino , Masculino , Leucemia Mieloide Aguda/terapia , Leucemia Mieloide Aguda/líquido cefalorraquidiano , Leucemia Mieloide Aguda/mortalidade , Estudos Retrospectivos , Adulto , Prognóstico , Pessoa de Meia-Idade , Seguimentos , Adolescente , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Taxa de Sobrevida , Adulto Jovem , Doença Enxerto-Hospedeiro/etiologia , Doença Enxerto-Hospedeiro/líquido cefalorraquidiano , Doença Enxerto-Hospedeiro/diagnóstico , Doença Enxerto-Hospedeiro/mortalidade , Idoso , Criança , Citologia
2.
Artigo em Inglês | MEDLINE | ID: mdl-38804044

RESUMO

Epigenetic modifications play an important role in cellular senescence, and enhancer of zeste homolog 2 (EZH2) is a key methyltransferase involved in epigenetic remodeling in multiple myeloma (MM) cells. We have previously demonstrated that GSK126, a specific EZH2 inhibitor, exhibits anti-MM therapeutic efficacy and safety in vivo and in vitro; however, its specific mechanism remains unclear. This study shows that GSK126 induces cellular senescence in MM, which is characterized by the accumulation of senescence-associated heterochromatin foci (SAHF) and p21, and increased senescence-associated ß galactosidase activity. Furthermore, EZH2 is inhibited in ribonucleotide reductase regulatory subunit M2 (RRM2) overexpression OCI-MY5 and RPMI-8226 cells. RRM2 overexpression inhibits the methyltransferase function of EZH2 and promotes its degradation through the ubiquitin-proteasome pathway, thereby inducing cellular senescence. In this senescence model, Lamin B1, a key component of the nuclear envelope and a marker of senescence, does not decrease but instead undergoes aberrant accumulation. Meanwhile, phosphorylation of extracellular signal-regulated protein kinase (ERK1/2) is significantly increased. The inhibition of ERK1/2 phosphorylation in turn partially restores Lamin B1 level and alleviates senescence. These findings suggest that EZH2 inhibition increases Lamin B1 level and induces senescence by promoting ERK1/2 phosphorylation. These data indicate that EZH2 plays an important role in MM cellular senescence and provide insights into the relationships among Lamin B1, p-ERK1/2, and cellular senescence.

3.
Arch Biochem Biophys ; 754: 109929, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38367794

RESUMO

Diffuse large B-cell lymphoma (DLBCL) is the most common type of non-Hodgkin lymphoma. Although treatment options have improved, a large proportion of patients show low survival rates, highlighting an urgent need for novel therapeutic strategies. The aim of this study was to investigate the efficacy of the new small-molecule compound dihydrocelastrol (DHCE), acquired through the structural modification of celastrol (CE), in the treatment of DLBCL. DHCE showed potent anti-lymphoma efficacy and synergistic effects with doxorubicin. DHCE triggered DLBCL cell apoptosis and G0/G1-phase blockade, thereby hindering angiogenesis. DHCE inhibited B-cell receptor cascade signalling and Jun B and p65 nuclear translocation, thereby suppressing pro-tumourigenic signalling. Finally, DHCE exerted lower toxicity than CE, which showed severe hepatic, renal, and reproductive toxicity in vivo. Our findings support further investigation of the clinical efficacy of DHCE against DLBCL.


Assuntos
Linfoma Difuso de Grandes Células B , Triterpenos Pentacíclicos , Fator de Transcrição AP-1 , Humanos , Fator de Transcrição AP-1/metabolismo , Angiogênese , Transdução de Sinais , Apoptose , Linfoma Difuso de Grandes Células B/metabolismo , Linhagem Celular Tumoral , Proliferação de Células
4.
Clin. transl. oncol. (Print) ; 25(8): 2472-2486, aug. 2023. graf
Artigo em Inglês | IBECS | ID: ibc-222424

RESUMO

Introduction This study aimed to develop a prognostic nomogram for patients with gastric cancer (GC) based on the levels of programmed death 1 ligand 1 (PDL1) and carcinoembryonic antigen (CEA). Methods The nomogram was developed using data from a primary cohort of 247 patients who had been clinicopathologically diagnosed with GC, as well as a validation cohort of 63 patients. Furthermore, the nomogram divided the patients into three different risk groups for overall survival (OS)—the low-risk, middle-risk, and high-risk groups. Univariate and multivariate Cox hazard analyses were used to determine all of the factors included in the model. Decision curve analysis and receiver operating characteristic (ROC) curves were used to assess the accuracy of the nomogram. Results The Kaplan–Meier survival analysis revealed that metastasis stage, clinical stage, and CEA and PDL1 levels were predictors for progress-free survival (PFS) and OS of patients with GC. Metastasis stage, clinical stage, and CEA and PDL1 levels were found to be independent risk factors for the PFS and OS of patients with GC in a multivariate analysis, and the nomogram was based on these factors. The concordance index of the nomogram was 0.763 [95% confidence interval (CI) 0.740–0.787]. The area under the concentration–time curve of the nomogram model was 0.81 (95% CI 0.780–0.900). According to the decision curve analysis and ROC curves, the nomogram model had a higher overall net efficiency in forecasting OS than clinical stage, CEA and PDL1 levels. Conclusion In conclusion, we proposed a novel nomogram that integrated PDL1 and CEA, and the proposed nomogram provided more accurate and useful prognostic predictions for patients with GC (AU)


Assuntos
Humanos , Antígeno Carcinoembrionário/sangue , Neoplasias Gástricas/sangue , Nomogramas , Ligantes , Biomarcadores Tumorais/sangue , Morte Celular , Prognóstico
5.
Angew Chem Int Ed Engl ; 62(29): e202302812, 2023 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-37148162

RESUMO

Ziconotide (ω-conotoxin MVIIA) is an approved analgesic for the treatment of chronic pain. However, the need for intrathecal administration and adverse effects have limited its widespread application. Backbone cyclization is one way to improve the pharmaceutical properties of conopeptides, but so far chemical synthesis alone has been unable to produce correctly folded and backbone cyclic analogues of MVIIA. In this study, an asparaginyl endopeptidase (AEP)-mediated cyclization was used to generate backbone cyclic analogues of MVIIA for the first time. Cyclization using six- to nine-residue linkers did not perturb the overall structure of MVIIA, and the cyclic analogues of MVIIA showed inhibition of voltage-gated calcium channels (CaV 2.2) and substantially improved stability in human serum and stimulated intestinal fluid. Our study reveals that AEP transpeptidases are capable of cyclizing structurally complex peptides that chemical synthesis cannot achieve and paves the way for further improving the therapeutic value of conotoxins.


Assuntos
Conotoxinas , ômega-Conotoxinas , Humanos , ômega-Conotoxinas/farmacologia , ômega-Conotoxinas/uso terapêutico , Analgésicos/farmacologia , Analgésicos/uso terapêutico , Conotoxinas/farmacologia , Canais de Cálcio/química , Bloqueadores dos Canais de Cálcio/farmacologia
7.
Clin Transl Oncol ; 25(8): 2472-2486, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37084151

RESUMO

INTRODUCTION: This study aimed to develop a prognostic nomogram for patients with gastric cancer (GC) based on the levels of programmed death 1 ligand 1 (PDL1) and carcinoembryonic antigen (CEA). METHODS: The nomogram was developed using data from a primary cohort of 247 patients who had been clinicopathologically diagnosed with GC, as well as a validation cohort of 63 patients. Furthermore, the nomogram divided the patients into three different risk groups for overall survival (OS)-the low-risk, middle-risk, and high-risk groups. Univariate and multivariate Cox hazard analyses were used to determine all of the factors included in the model. Decision curve analysis and receiver operating characteristic (ROC) curves were used to assess the accuracy of the nomogram. RESULTS: The Kaplan-Meier survival analysis revealed that metastasis stage, clinical stage, and CEA and PDL1 levels were predictors for progress-free survival (PFS) and OS of patients with GC. Metastasis stage, clinical stage, and CEA and PDL1 levels were found to be independent risk factors for the PFS and OS of patients with GC in a multivariate analysis, and the nomogram was based on these factors. The concordance index of the nomogram was 0.763 [95% confidence interval (CI) 0.740-0.787]. The area under the concentration-time curve of the nomogram model was 0.81 (95% CI 0.780-0.900). According to the decision curve analysis and ROC curves, the nomogram model had a higher overall net efficiency in forecasting OS than clinical stage, CEA and PDL1 levels. CONCLUSION: In conclusion, we proposed a novel nomogram that integrated PDL1 and CEA, and the proposed nomogram provided more accurate and useful prognostic predictions for patients with GC.


Assuntos
Nomogramas , Neoplasias Gástricas , Humanos , Antígeno Carcinoembrionário , Ligantes , Prognóstico
8.
Int J Mol Sci ; 24(6)2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36982972

RESUMO

Gomesin is a cationic antimicrobial peptide which is isolated from the haemocytes of the Brazilian tarantula Acanthoscurria gomesiana and can be produced chemically by Fmoc solid-phase peptide synthesis. Gomesin exhibits a range of biological activities, as demonstrated by its toxicity against therapeutically relevant pathogens such as Gram-positive or Gram-negative bacteria, fungi, cancer cells, and parasites. In recent years, a cyclic version of gomesin has been used for drug design and development as it is more stable than native gomesin in human serum and can penetrate and enter cancer cells. It can therefore interact with intracellular targets and has the potential to be developed as a drug lead for to treat cancer, infectious diseases, and other human diseases. This review provides a perspective on the discovery, structure-activity relationships, mechanism of action, biological activity, and potential clinical applications of gomesin.


Assuntos
Peptídeos Antimicrobianos , Neoplasias , Humanos , Peptídeos Catiônicos Antimicrobianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/uso terapêutico , Neoplasias/tratamento farmacológico , Relação Estrutura-Atividade
9.
World J Clin Cases ; 11(7): 1569-1575, 2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36926392

RESUMO

BACKGROUND: A large percentage of patients with ectopic pancreas are asymptomatic. When present, the symptoms are typically non-specific. These lesions are predominantly located in the stomach and benign in nature. Synchronous multiple early gastric cancer (SMEGC) (two or more simultaneous malignant lesions with early gastric cancer) is relatively rare and particularly easy to overlook during endoscopic examination. The prognosis of SMEGC is generally poor. We report a rare case of ectopic pancreas with concomitant SMEGC. CASE SUMMARY: A 74-year-old woman presented with paroxysmal upper abdominal pain. On initial investigations, she tested positive for Helicobacter pylori (H. pylori). She underwent esophagogastroduodenoscopy which revealed a 1.5 cm × 2 cm major lesion at the greater curvature and a 1 cm minor lesion at the lesser curvature of the stomach. On endoscopic ultrasound, the major lesion showed hypoechoic changes, uneven internal echoes and unclear boundaries between some areas and the muscularis propria. Endoscopic submucosal dissection was performed to excise the minor lesion. A laparoscopic resection was chosen for the major lesion. On histopathological examination, the major lesion contained high grade intraepithelial neoplasia with a small focus of cancer. A separate underlying ectopic pancreas was found under this lesion. The minor lesion contained high grade intraepithelial neoplasia. In this case, the patient was diagnosed with SMEGC with concomitant ectopic pancreas in the stomach. CONCLUSION: Patients with atrophy, H. pylori, and other risk factors should be carefully investigated to avoid missing other lesions including SMEGC and ectopic pancreas.

10.
Macromol Rapid Commun ; 44(8): e2300014, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36790071

RESUMO

Inverse vulcanization utilizes an organic compound as reagent for crosslinking elemental sulfur to result in corresponding polymeric material with a high sulfur content. This work, employing 1,3,5-triisopropylbenzene (TIPB) as the reagent, demonstrates the first attempt on extending the scope of crosslinking agents of inverse vulcanization to saturate compounds. Under nuclear magnetic spectroscopic analysis, the reactions between TIPB and elemental sulfur take places through ring-opening reaction of S8 resulting in sulfur radicals at sulfur chain ends, radicals transferring to isopropyl groups of TIPB, and radical coupling reactions between carbon radicals and sulfur radicals. The obtained products are similar to the sulfur polymers from conventional inverse vulcanization processes and show self-healing property.


Assuntos
Compostos Orgânicos , Enxofre , Indicadores e Reagentes , Enxofre/química , Polímeros/química , Carbono
11.
Ann Behav Med ; 57(1): 93-97, 2023 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-35815757

RESUMO

BACKGROUND: The timing and regularity of eating patterns could play a role in systemic inflammation, as circadian clocks responsible for daily rhythms of inflammatory signaling are entrained by food intake. PURPOSE: To evaluate associations of intra-weekly and weekday-weekend differences in eating timing patterns with high-sensitivity C-reactive protein (hsCRP). METHODS: A community-based sample of 103 U.S. women from the American Heart Association Go Red for Women Strategically Focused Research Network completed a meal-timing questionnaire and provided a blood sample for measurement of hsCRP. Differences in weekday versus weekend eating start time, eating end time, and nightly fasting duration were calculated as eating jetlag metrics. Intra-weekly variability in eating timing patterns was defined by the standard deviation (SD) of these variables. Multivariable linear regression models were used to evaluate cross-sectional associations of eating timing variability metrics with hsCRP. RESULTS: Each additional 30-min difference in weekday-weekend eating end time was related to 13% higher hsCRP (p = .023). Similarly, every 30-min increase in eating end time SD, reflecting greater variability in timing of last eating occasion, was associated with 29% higher hsCRP. Per 1-hr weekday-weekend difference in nightly fasting duration, there was a 45% elevation in hsCRP (p = .003). Every 30-min increase in nightly fasting duration SD, representing greater variability in span of the daily fasting/eating periods, was associated with 46% higher hsCRP. CONCLUSIONS: Variable eating timing patterns were associated with higher hsCRP. Intervention studies are needed to determine whether stabilizing the timing of eating occasions may represent a novel strategy to reduce chronic inflammation.


Assuntos
Proteína C-Reativa , Sono , Humanos , Feminino , Estudos Transversais , Comportamento Alimentar , Fatores de Risco , Inflamação , Ingestão de Alimentos
12.
Front Mol Biosci ; 10: 1302017, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38192334

RESUMO

Low back pain (LBP) is a major public health problem worldwide and a significant health and economic burden. Intervertebral disc degeneration (IDD) is the reason for LBP. However, we have not identified effective therapeutic strategies to address this challenge. With accumulating knowledge on the role of circular RNAs in the pathogenesis of IDD, we realised that circular RNAs (circRNAs) may have tremendous therapeutic potential and clinical application prospects in this field. This review presents an overview of the current understanding of characteristics, classification, biogenesis, and function of circRNAs and summarises the protective and detrimental circRNAs involved in the intervertebral disc that have been studied thus far. This review is aimed to help researchers better understand the regulatory role of circRNAs in the progression of IDD, reveal their clinical therapeutic potential, and provide a theoretical basis for the prevention and targeted treatment of IDD.

13.
Zhongguo Zhong Yao Za Zhi ; 47(22): 6005-6019, 2022 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-36471951

RESUMO

Patrinia villosa, regarding its functions in clearing heat and detoxification and eliminating carbuncles and pus, is widely used as a traditional medicinal herb that contains rich nutrition and substances such as various amino acids, vitamins, and soluble su-gar, and it is also an edible wild herb in Chinese folk tradition for 2 000 years. In 1973, Japanese scholars firstly separated three iridoids from Japanese P. villosa, and by 2021, chemical components such as flavonoids, iridoids, organic acids, triterpenoids, phenylpropanoids, and steroids have been found, which have multiple pharmacological effects, including antioxidant, antitumor, anti-diarrhea, antibacterial, sedative, and liver protection capabilities. Studies indicate that flavonoids, saponins, phenylpropanoids, and triterpenoids in P. villosa are vital substances for its pharmacological activities. However, the quality of this medicinal material cannot be controlled due to the unclear records in ancient books in the past dynasties and different drug use habits in different places, and thus its circulation is chaotic. At present, researchers have used flavonoids, organic acids, phenylpropanoids, triterpenoid saponins, and other compounds to conduct studies in this regard. Therefore, on the basis of the existing literature resources, we comprehensively summarize the chemical constituents, pharmacological activities, and quality control of P. villosa to further provide a reference for the safety and effectiveness of clinical drug use and lay a foundation for the follow-up experimental research.


Assuntos
Patrinia , Saponinas , Triterpenos , Patrinia/química , Flavonoides/farmacologia , Triterpenos/farmacologia , Iridoides , Controle de Qualidade
14.
Artigo em Inglês | MEDLINE | ID: mdl-36361225

RESUMO

Rapid urbanization has triggered more serious urban flood risks. Many studies have focused on intra-urban flooding, but less attention has been paid to rainfall and flood risks at the urban fringe. Nowadays, China is vigorously promoting the construction of sponge cities in the whole area. It is important to study the construction of sponge cities in shallow mountainous areas, which are an important barrier between cities and mountains. The purpose of this paper is to investigate the performance of Low-Impact Development (LID) facilities under different rainfall scenarios in developed shallow mountainous areas. The second garden and flower exposition ("the Expo Park") in Hebei Province is used as an example. The SWMM and MIKE21 models were used to simulate the hydrological processes before and after the construction of "the Expo Park", and the models were calibrated with the measured data. Peak flow rate, outflow volume, rainfall-outflow ratio, runoff velocity, and water feature area of the water system were used as indicators to evaluate their effectiveness. The results showed that the placement of LID facilities had a positive impact on the construction of the shallow mountain area. Specifically, (1) LID facilities can reduce the peak flow rate, delayed peak flow time, outflow volume, and rainfall outflow ratio of stormwater runoff in mountainous areas; and (2) they can effectively collect rainwater and become a supplement to the landscape water system of the site. These findings provide a scientific basis for the construction of LID facilities in shallow mountainous areas, which is important for the development and flood management of shallow mountainous areas.


Assuntos
Chuva , Movimentos da Água , Água , Hidrologia , Cidades , China
15.
Bioengineering (Basel) ; 9(7)2022 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-35877336

RESUMO

Fusobacterium nucleatum (F. nucleatum) is an oral anaerobe that plays a role in several oral diseases. However, F. nucleatum is also found in other tissues of the digestive tract, and several studies have recently reported that the level of F. nucleatum is significantly elevated in malignant tumors of the digestive tract. F. nucleatum is proposed as one of the risk factors in the initiation and progression of digestive tract malignant tumors. In this review, we summarize recent reports on F. nucleatum and its role in digestive tract cancers and evaluate the mechanisms underlying the action of F. nucleatum in digestive tract cancers.

16.
J Biol Chem ; 298(8): 102218, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35780839

RESUMO

The stinging hairs of plants from the family Urticaceae inject compounds that inflict pain to deter herbivores. The sting of the New Zealand tree nettle (Urtica ferox) is among the most painful of these and can cause systemic symptoms that can even be life-threatening; however, the molecular species effecting this response have not been elucidated. Here we reveal that two classes of peptide toxin are responsible for the symptoms of U. ferox stings: Δ-Uf1a is a cytotoxic thionin that causes pain via disruption of cell membranes, while ß/δ-Uf2a defines a new class of neurotoxin that causes pain and systemic symptoms via modulation of voltage-gated sodium (NaV) channels. We demonstrate using whole-cell patch-clamp electrophysiology experiments that ß/δ-Uf2a is a potent modulator of human NaV1.5 (EC50: 55 nM), NaV1.6 (EC50: 0.86 nM), and NaV1.7 (EC50: 208 nM), where it shifts the activation threshold to more negative potentials and slows fast inactivation. We further found that both toxin classes are widespread among members of the Urticeae tribe within Urticaceae, suggesting that they are likely to be pain-causing agents underlying the stings of other Urtica species. Comparative analysis of nettles of Urtica, and the recently described pain-causing peptides from nettles of another genus, Dendrocnide, indicates that members of tribe Urticeae have developed a diverse arsenal of pain-causing peptides.


Assuntos
Neurotoxinas , Peptídeos , Toxinas Biológicas , Urticaceae , Humanos , Neurotoxinas/química , Dor , Técnicas de Patch-Clamp , Peptídeos/química , Peptídeos/toxicidade , Toxinas Biológicas/química , Urticaceae/química , Canais de Sódio Disparados por Voltagem/efeitos dos fármacos
17.
J Exp Bot ; 73(18): 6103-6114, 2022 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-35724659

RESUMO

Plant molecular farming aims to provide a green, flexible, and rapid alternative to conventional recombinant expression systems, capable of producing complex biologics such as enzymes, vaccines, and antibodies. Historically, the recombinant expression of therapeutic peptides in plants has proven difficult, largely due to their small size and instability. However, some plant species harbour the capacity for peptide backbone cyclization, a feature inherent in stable therapeutic peptides. One obstacle to realizing the potential of plant-based therapeutic peptide production is the proteolysis of the precursor before it is matured into its final stabilized form. Here we demonstrate the rational domestication of Nicotiana benthamiana within two generations to endow this plant molecular farming host with an expanded repertoire of peptide sequence space. The in planta production of molecules including an insecticidal peptide, a prostate cancer therapeutic lead, and an orally active analgesic is demonstrated.


Assuntos
Produtos Biológicos , Domesticação , Proteínas de Plantas/metabolismo , Nicotiana/genética , Nicotiana/metabolismo , Plantas/metabolismo , Peptídeos/metabolismo , Produtos Biológicos/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
18.
Chirality ; 34(7): 1019-1034, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35521642

RESUMO

A readily available chiral cyclohexanediamine-derived bifunctional tertiary amine-squaramide catalyst is more effective for the asymmetric dearomative 1,3-dipolar cycloaddition of 2-nitrobenzofurans and N-2,2,2-trifluoroethylisatin ketimines. A range of structurally diverse spiro-fused polyheterocyclic compounds containing oxindole, pyrrolidine, and hydrobenzofuran motifs were smoothly obtained in excellent results (up to 99% yield, >20:1 dr in all cases and up to 99% ee). This method features high efficiency, mild reaction conditions, exquisite asymmetric induction, wide functional group tolerance, great potential for scale-up synthesis, and attractive product diversification.


Assuntos
Iminas , Compostos de Espiro , Benzofuranos , Reação de Cicloadição , Nitrilas , Estereoisomerismo
19.
Int J Lab Hematol ; 44(5): 892-899, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35505580

RESUMO

INTRODUCTION: Adult acute myeloid leukaemia (AML) patients with complex karyotype (CK) generally have unfavourable outcomes. CK commonly co-exists with characteristic chromosomal and genetic abnormalities such as monosomal karyotype (MK), -17 or 17p- [abn(17p)] and TP53 mutations. Their individual prognostic significance needs to be clarified. METHODS: Seventy-three adult CK-AML patients and eleven adult non-CK-AML patients with TP53 mutations (non-CK/TP53mu ) who were diagnosed and received therapy at our institute were enrolled. One hundred and fifty-seven AML cases retrieved from the cancer genome atlas (TCGA) for validation. RESULTS: Among CK-AML patients, those with TP53 mutations (CK/TP53mu ) had significantly lower rates of 1-course induction complete remission (CR), 2-year relapse-free survival (RFS) and 2-year overall survival (OS) than those without TP53 mutations (CK/TP53wt ); whereas, abn(17p) did not have the above impacts; MK was significantly associated with a lower 2-year OS rate but was not related to the rates of CR and RFS. Multivariate analysis showed that it were TP53 mutations and treating with chemotherapy alone but not MK and abn(17p) that independently predicted the adverse prognosis for RFS and OS in CK-AML. Furthermore, non-CK/TP53mu patients showed similar rates of CR, RFS and OS to CK/TP53mu patients. Validation using the TCGA cohort showed that CK/TP53mu patients had a significantly lower 2-year OS rate than CK/TP53wt patients, whereas abn(17p) and MK did not impact OS; the 2-year OS rate of patients with CK/TP53wt was similar to that of patients with intermediate-risk cytogenetics. CONCLUSION: Adult CK-AML patients have varied risks and TP53 mutations seem to be an independent adverse prognostic factor.


Assuntos
Leucemia Mieloide Aguda , Monossomia , Cariótipo Anormal , Adulto , Humanos , Cariótipo , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Mutação , Recidiva Local de Neoplasia , Prognóstico , Proteína Supressora de Tumor p53/genética
20.
Phytochemistry ; 195: 113053, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34923360

RESUMO

Cyclotides are a class of ribosomally-synthesized plant peptides that function in plants as a defense against insects and fungal pathogens. Their unique structure comprises a cyclized peptide backbone threaded by three disulfide bonds, that imparts structural stability, a desirable quality for peptide-based therapeutics or insecticides. Producing these peptides synthetically is challenging due to the amount of chemical waste produced and inefficiency of folding certain cyclotides. Thus, it is desirable to develop a means to access cyclotide biosynthesis in their native hosts, cultured in defined conditions, at both laboratory and commercial scale. Here we developed suspension cell cultures from two species previously unexplored for cyclotide production in suspension cells, Clitoria ternatea L., Hybanthus enneaspermus F. Muell., as well as with Oldenlandia affinis (Roem. & Schult.) DC., a species reported previously to accumulate cyclotides in cell suspensions. We assessed the growth rate, cyclotide production and gene expression for the various species. We found that while many cyclotides had reduced expression in Oldenlandia affinis suspension cells when compared to plant organs, those in Clitoria ternatea and Hybanthus enneaspermus maintained or increased expression levels. The cyclotides that continued to be expressed in suspension cultures shared similar sequence and biophysical properties as a group, regardless of phylogenetic origin of the host. Of particular interest was the discovery of inducibility by NaCl of cyclotide expression in O. affinis, cycloviolacin O2 expression in O. affinis, and the scale up of cycloviolacin O2 production in H. enneaspermus. Together the results presented here highlight the utility of plant cell suspensions as modalities to produce macrocyclic peptides.


Assuntos
Ciclotídeos , Sequência de Aminoácidos , Ciclotídeos/genética , Agricultura Molecular , Filogenia , Células Vegetais/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Suspensões
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