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1.
Nat Prod Res ; : 1-7, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39094017

RESUMO

Four diterpenes of the daphnane type were isolated from a methanol extract of the flower buds of Daphne genkwa, the two of them were new structures named genkwadanes J (1) and K (2). Their structures were determined based on analysis of their 1D- and 2D-NMR, HRESIMS and ECD calculations. Among the isolates, the cytotoxicity was assessed via the MTT method using the K562, MCF-7 and HeLa cancer cell lines, the positive control was taxol. Compounds 1 and 3 exhibited appreciable cytotoxic activity against the K562 cancer cell line with IC50 values between 6.58 and 5.33 µM. Compounds 2 and 4 showed noteworthy inhibitory effects against the MCF-7 cell line with IC50 values of 3.25 and 2.56 µM, respectively. All compounds showed weak cytotoxicities to the Hela cell line with IC50 values in the range of 20.19-55.23 µM.

2.
Cureus ; 16(6): e63535, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39086773

RESUMO

Background Selenium nanoparticles (SeNPs) are one of the metal nanoparticles that have been widely utilized for their anti-microbial, anti-oxidant, anti-inflammatory activities, and other biomedical applications. Tridax procumbens (TP) stem extract is a promising herb species rich in flavonoids, tannins, alkaloids, phytosterols, and hydroxycinnamates, which play a major role in wound healing applications.  Aim The study aims to synthesize SeNPs using TP stem extract, characterizations, and its biomedical applications. Materials and methods SeNPs were synthesized using TP stem extract. The green synthesis of SeNPs was confirmed by ultraviolet-visible (UV-vis) spectra analysis. The synthesized SeNPs were characterized using Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The agar well diffusion method was utilized to evaluate the anti-bacterial properties of the green synthesized SeNPs using TP stem extract. The anti-oxidant effect of SeNPs was tested using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, ferric-reducing anti-oxidant power assay (FRAP), and hydroxyl radical scavenging assay (H2O2). The anti-inflammatory effect was investigated using the bovine serum albumin assay and egg albumin denaturation method, and the cytotoxic effect of the green synthesized SeNPs was tested using the brine shrimp lethality (BSL) assay. Results The green synthesis of SeNPs was confirmed using different types of analysis techniques. The characterizations were done by UV-visible spectroscopy analysis, exhibiting a maximum peak at the range of 330 nm. SEM analysis revealed the shape of the nanoparticle to be hexagonal. The agar well diffusion method exhibited the anti-bacterial efficacy of SeNPs against wound microorganisms with a zone of inhibition of 14.6 mm for Escherichia coli (E. coli), 15.8 mm for Staphylococcus aureus (S. aureus), and 15.4 mm for Pseudomonas aeruginosa (P. aeruginosa). The TP stem-mediated SeNPs showed potential effects in anti-oxidant, anti-inflammatory, and cytotoxic activity, which shows very little toxicity. Conclusion Overall, the green synthesis of TP-stem-mediated SeNPs has great potential in biomedical applications. Thus, the synthesized SeNPs exhibit significant anti-bacterial efficacy against wound pathogens. The TP stem-mediated SeNPs showed potential effects in anti-oxidant, anti-inflammatory, and cytotoxic activity, which shows low toxicity. Furthermore, the green-synthesized SeNPs can be utilized in therapeutic management.

3.
Front Immunol ; 15: 1411957, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39114656

RESUMO

Introduction: CD8+ cytotoxic T lymphocytes (CTLs) are highly effective in defending against viral infections and tumours. They are activated through the recognition of peptide-MHC-I complex by the T-cell receptor (TCR) and co-stimulation. This cognate interaction promotes the organisation of intimate cell-cell connections that involve cytoskeleton rearrangement to enable effector function and clearance of the target cell. This is key for the asymmetric transport and mobilisation of lytic granules to the cell-cell contact, promoting directed secretion of lytic mediators such as granzymes and perforin. Mitochondria play a role in regulating CTL function by controlling processes such as calcium flux, providing the necessary energy through oxidative phosphorylation, and its own protein translation on 70S ribosomes. However, the effect of acute inhibition of cytosolic translation in the rapid response after TCR has not been studied in mature CTLs. Methods: Here, we investigated the importance of cytosolic protein synthesis in human CTLs after early TCR activation and CD28 co-stimulation for the dynamic reorganisation of the cytoskeleton, mitochondria, and lytic granules through short-term chemical inhibition of 80S ribosomes by cycloheximide and 80S and 70S by puromycin. Results: We observed that eukaryotic ribosome function is required to allow proper asymmetric reorganisation of the tubulin cytoskeleton and mitochondria and mTOR pathway activation early upon TCR activation in human primary CTLs. Discussion: Cytosolic protein translation is required to increase glucose metabolism and degranulation capacity upon TCR activation and thus to regulate the full effector function of human CTLs.


Assuntos
Linfócitos T CD8-Positivos , Citosol , Ativação Linfocitária , Mitocôndrias , Biossíntese de Proteínas , Receptores de Antígenos de Linfócitos T , Humanos , Receptores de Antígenos de Linfócitos T/metabolismo , Receptores de Antígenos de Linfócitos T/imunologia , Ativação Linfocitária/imunologia , Citosol/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Mitocôndrias/metabolismo , Mitocôndrias/imunologia , Citoesqueleto/metabolismo , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/metabolismo , Ribossomos/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo
4.
Adv Exp Med Biol ; 1448: 9-19, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39117804

RESUMO

Hemophagocytic lymphohistiocytosis (HLH) is a severe cytokine storm syndrome (CSS), which until the turn of the century, was barely known but is now receiving increased attention. The history of HLH dates back to 1939 when it was first described in adults, to be followed in 1952 by the first description of its primary, familial form in children. Secondary forms of HLH are far more frequent and occur with infections, malignancies, metabolic diseases, iatrogenic immune suppression, and autoinflammatory/autoimmune diseases. Identification of the genetic defects leading to the defective function of natural killer (NK) cells and cytotoxic T cells as well as the corresponding mouse models have revolutionized our understanding of HLH and of immune function. Diagnosis relies on clinical and laboratory criteria; functional and genetic tests can help separate primary from secondary forms. Treatment with immunochemotherapy and hematopoietic stem cell transplantation has considerably improved survival in children with primary HLH, a formerly uniformly fatal disease.


Assuntos
Linfo-Histiocitose Hemofagocítica , Linfo-Histiocitose Hemofagocítica/terapia , Linfo-Histiocitose Hemofagocítica/diagnóstico , Linfo-Histiocitose Hemofagocítica/genética , Linfo-Histiocitose Hemofagocítica/imunologia , Humanos , História do Século XX , Animais , História do Século XXI , Células Matadoras Naturais/imunologia , Transplante de Células-Tronco Hematopoéticas
5.
Cancer Sci ; 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39118263

RESUMO

Cytoskeleton-associated protein 4 (CKAP4) is a cell surface receptor for Dickkopf 1 (DKK1), a secreted protein. The DKK1-CKAP4 pathway is activated in various malignant tumors, including pancreatic, lung, esophageal, and liver cancers, to promote tumor growth. Thus, CKAP4 has been expected to represent a novel molecular target of cancer therapy. Recombinant mouse anti-CKAP4 antibodies were generated based on an original mouse antibody (3F11-2B10) and inhibited DKK1-CKAP4 signaling and xenograft tumor formation induced by pancreatic cancer cells, which was comparable with 3F11-2B10. From the 3F11-2B10 nucleotide sequence, humanized anti-CKAP4 antibody (Hv1Lt1) was subsequently developed. The binding affinity of Hv1Lt1 for CKAP4 was superior to that of 3F11-2B10. Hv1Lt1 inhibited DKK1 binding to CKAP4, AKT activity, and sphere formation of pancreatic cancer cells, which was comparable with 3F11-2B10. Hv1Lt1 also suppressed xenograft tumor formation induced by human pancreatic cancer cells and tumor growth in murine cancer models, in which murine pancreatic cancer organoids were orthotopically transplanted into the pancreas. In resected tumor samples from mice treated with Hv1Lt1, anti-tumor immune reactions were modulated and cytotoxic T cells were highly infiltrated in the tumor microenvironment. Additionally, combination of Hv1Lt1 and other chemotherapy drugs exhibited stronger effects compared with monotherapy. These results suggest that Hv1Lt1 represents a promising anti-cancer therapy.

6.
Inn Med (Heidelb) ; 2024 Aug 08.
Artigo em Alemão | MEDLINE | ID: mdl-39115593

RESUMO

Immune checkpoint inhibitors (ICI) represent a breakthrough in cancer therapy. They are effective in various tumor entities and can be used in more and more treatment settings. This leads to an increase in the number and complexity of cases with immune-related adverse events (irAE). The most common irAE are cutaneous, gastrointestinal and endocrine side effects, whereas less common irAE include pneumonitis, nephritis, myocarditis or neurological reactions. IrAE can usually be successfully treated, mainly with corticosteroids or other immunosuppressants, but they can also result in long-term sequelae or death. The optimal management of patients with steroid-refractory or steroid-dependent side effects still remains unclear. Broad awareness of these irAE across specialties is therefore of crucial importance to ensure early diagnosis and to improve irAE management.

7.
Biochim Biophys Acta Rev Cancer ; 1879(5): 189161, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39096977

RESUMO

Immune checkpoint blockade (ICB) therapy has achieved broad applicability and durable clinical responses across cancer types. However, the overall response rate remains suboptimal because some patients do not respond or develop drug resistance. The low infiltration of CD8+ cytotoxic T cells (CTLs) in the tumor microenvironment due to insufficient antigen presentation is closely related to the innate resistance to ICB. The duration and spatial distribution of major histocompatibility complex class I (MHC-I) expression on the cell surface is critical for the efficient presentation of endogenous tumor antigens and subsequent recognition and clearance by CTLs. Tumor cells reduce the surface expression of MHC-I via multiple mechanisms to impair antigen presentation pathways and evade immunity and/or develop resistance to ICB therapy. As an increasing number of studies have focused on membrane MHC-I trafficking and degradation in tumor cells, which may impact the effectiveness of tumor immunotherapy. It is necessary to summarize the mechanism regulating membrane MHC-I translocation into the cytoplasm and degradation via the lysosome. We reviewed recent advances in the understanding of endosomal-lysosomal MHC-I transport and highlighted the means exploited by tumor cells to evade detection and clearance by CTLs. We also summarized new therapeutic strategies targeting these pathways to enhance classical ICB treatment and provide new avenues for optimizing cancer immunotherapy.

8.
Plants (Basel) ; 13(15)2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39124129

RESUMO

The study evaluated the preservative potential of Lafoensia replicata Pohl. leaf extracts in cosmetics, highlighting their antioxidant, antimicrobial, and in vitro cytotoxic activities for ethanolic extract prepared by the maceration and tincture method. Total phenol content showed a higher phenol concentration in ethanolic extract and tinctures, and by LC-MS/MS-ESI-QTOF analysis, flavonoids, hydrolyzed tannins, and phenolic acids were identified. The ethanolic extract and tincture showed high antimicrobial activity against Staphylococcus aureus, Pseudomonas aeruginosa, and Candida albicans (MIC < 50 µg mL-1), high antioxidant activity (EC50 < 50 µg mL-1 in the DPPH method, and results > 450 µmol trolox equivalent in the ABTS and FRAP method), and low cytotoxicity in human keratinocytes (IC50 > 350 µg mL-1). The results suggest these extracts could be an alternative to synthetic preservatives in the cosmetic industry.

9.
Plants (Basel) ; 13(15)2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39124141

RESUMO

This study investigates the phytochemical composition and biological activities of hemp (Cannabis sativa L.) leaves, flowers' methanolic extracts from the Sofia variety, and its sprouts cultivated under different light conditions (natural light, darkness, blue, and white LED light for 5, 7, and 9 days). Phytochemical analysis using HPLC identified four key polyphenolic compounds in sprouts' extracts: chlorogenic, caffeic, and gallic acids, and myricetin, with a predomination of the chlorogenic acid. In contrast, leaves and flowers' extracts contained cannflavins A and B and chlorogenic, p-coumaric, and ferulic acids, with a significant presence of isochlorogenic acid. Antioxidant capacity, assessed by FRAP method, revealed higher antioxidant potential in leaves compared to flowers and sprouts, with sprouts grown under blue and white LED lights exhibiting the highest activity. Cytotoxic activity was evaluated on human colon cancer cell lines (HT29, HCT116, DLD-1) and normal colon epithelial cells (CCD 841 CoN). Results demonstrated significant and selective cytotoxicity against cancer cell lines, with leaves showing more pronounced effects than flowers, and sprouts only moderate activity. All samples revealed an anti-inflammatory effect in vitro. To conclude, sprouts, leaves, and flowers of the Sofia hemp may be considered promising products for chemoprevention in the future.

10.
Molecules ; 29(15)2024 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-39124943

RESUMO

Cancer is the second leading cause of death in the world following cardiovascular disease. Its treatment, including radiation therapy and surgical removal of the tumour, is based on pharmacotherapy, which prompts a constant search for new and more effective drugs. There are high costs associated with designing, synthesising, and marketing new substances. Drug repositioning is an attractive solution. Fluoroquinolones make up a group of synthetic antibiotics with a broad spectrum of activity in bacterial diseases. Moreover, those compounds are of particular interest to researchers as a result of reports of their antiproliferative effects on the cells of the most lethal cancers. This article presents the current progress in the development of new fluoroquinolone derivatives with potential anticancer and cytotoxic activity, as well as structure-activity relationships, along with possible directions for further development.


Assuntos
Antineoplásicos , Fluoroquinolonas , Fluoroquinolonas/química , Fluoroquinolonas/farmacologia , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Relação Estrutura-Atividade , Neoplasias/tratamento farmacológico , Animais , Antibacterianos/farmacologia , Antibacterianos/química , Reposicionamento de Medicamentos , Proliferação de Células/efeitos dos fármacos
11.
Molecules ; 29(15)2024 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-39124959

RESUMO

The objective of this study was to analyze the chemical composition and evaluate the biological capabilities of the essential oils (EOs) extracted from leaves and stems of wild Aeschynomene indica L. plants by the hydrodistillation method. By using GC-FID/MS, fifty-six and fifty-five compounds, representing 95.1 and 97.6% of the essential oils in the leaves and stems, respectively, were characterized. The predominant constituents of A. indica EOs were (E)-caryophyllene, linalool, viridiflorol, phytol, hexadecanoic acid, trans-verbenol, and α-guaiene. The antibacterial and synergistic activities of the EOs were assessed by microdilution and checkerboard assays. The results revealed a potent inhibition and bactericidal activity against Staphylococcus aureus and Bacillus subtilis with MICs of 0.312-0.625 mg/mL. When combined with traditional antibiotics, the essential oils of A. indica possessed excellent synergistic effects against all tested bacteria. Additionally, the EOs of A. indica leaves showed higher antioxidant activity (IC50 = 0.11 ± 0.01 µg/mL) compared to the stem oil (IC50 = 0.19 ± 0.01 µg/mL) using the ABTS radical scavenging assay. The in vitro cytotoxicity of EOs against human cancer cell lines HepG2, MCF-7, A-549, and HCT-116 was examined, and MTT assays showed that the EOs possessed a significant cytotoxic potential against MCF-7 breast cancer cells, with IC50 values of 10.04 ± 1.82 and 15.89 ± 1.66 µg/mL, and a moderate cytotoxic activity against other tested cells. In conclusion, the A. indica EOs could be considered a potential source of pharmacologically active compounds.


Assuntos
Antibacterianos , Antioxidantes , Testes de Sensibilidade Microbiana , Óleos Voláteis , Folhas de Planta , Caules de Planta , Óleos Voláteis/farmacologia , Óleos Voláteis/química , Antioxidantes/farmacologia , Antioxidantes/química , Folhas de Planta/química , Antibacterianos/farmacologia , Antibacterianos/química , Humanos , Caules de Planta/química , Bacillus subtilis/efeitos dos fármacos , Linhagem Celular Tumoral , Staphylococcus aureus/efeitos dos fármacos , Extratos Vegetais/farmacologia , Extratos Vegetais/química
12.
BMC Cancer ; 24(1): 980, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39118069

RESUMO

BACKGROUND: Lytic Epstein-Barr virus (EBV) infection plays a major role in the pathogenesis of nasopharyngeal carcinoma (NPC). For patients with recurrent or metastatic NPC and resistant to conventional therapies, adoptive cell therapy using EBV-specific cytotoxic T cells (EBV-CTLs) is a promising option. However, the long production period (around 3 to 4 weeks) and low EBV-CTL purity (approximately 40% of total CD8 T cells) in the cell product limits the application of EBV-CTLs in clinics. Thus, this study aimed to establish a protocol for the rapid production of EBV-CTLs. METHODS: By culturing peripheral blood mononuclear cells (PBMCs) from EBV-seropositive donors with EBV-specific peptides and interleukin (IL)-2, IL-15, and interferon α (IFN-α) for 9 days, we identified that IL-15 can enhance IL-2-mediated CTL activation and significantly increase the yield of CTLs. RESULTS: When IFN-α was used in IL-2/IL-15-mediated CTL production from days 0 to 6, the productivity of EBV-CTLs and EBV-specific cytotoxicity significantly were reinforced relative to EBV-CTLs from IL-2/IL-15 treatment. Additionally, IFN-α-induced production improvement of virus-specific CTLs was not only the case for EBV-CTLs but also for cytomegalovirus-specific CTLs. CONCLUSION: We established a novel protocol to rapidly expand highly pure EBV-CTLs from PBMCs, which can produce EBV-CTLs in 9 days and does not require feeder cells during cultivation.


Assuntos
Herpesvirus Humano 4 , Linfócitos T Citotóxicos , Humanos , Linfócitos T Citotóxicos/imunologia , Herpesvirus Humano 4/imunologia , Infecções por Vírus Epstein-Barr/imunologia , Infecções por Vírus Epstein-Barr/virologia , Interleucina-2/metabolismo , Interleucina-2/farmacologia , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/virologia , Interleucina-15/metabolismo , Interferon-alfa/metabolismo , Citotoxicidade Imunológica , Carcinoma Nasofaríngeo/virologia , Carcinoma Nasofaríngeo/imunologia , Carcinoma Nasofaríngeo/patologia , Neoplasias Nasofaríngeas/imunologia , Neoplasias Nasofaríngeas/virologia , Neoplasias Nasofaríngeas/patologia , Ativação Linfocitária/imunologia , Imunoterapia Adotiva/métodos
13.
J Virol Methods ; 329: 115006, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39121968

RESUMO

High-throughput screening requires assays that have flexibility to test large numbers of specimens while being accurate to ensure reproducibility across all specimens and variables tested. Previously, we used a low-throughput, cell-based assay to identify compounds with antiviral activity against polioviruses. In this report, we report the development and implementation of a high-throughput automation platform for the identification of compounds with antiviral activity against polioviruses. The platform uses off-the-shelf automated equipment combined with a modified assay, with minimal changes to existing laboratory space. We evaluated automation systems from Hudson Robotics Inc., Agilent Technologies, and a microplate reader from PerkinElmer during the platform design. Optimization for high throughput was focused on bulk reagent additions, serial dilutions, microplate washing and measuring results from the tens-to-hundreds of microplates. We evaluated the automated cell-based assay for selectivity, sensitivity, accuracy, precision, and reproducibility. This platform can be applied to screen novel antivirals against polioviruses and non-polio enteroviruses.

14.
Int J Mol Sci ; 25(15)2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39125711

RESUMO

Cystatin F (CstF) is a protease inhibitor of cysteine cathepsins, including those involved in activating the perforin/granzyme cytotoxic pathways. It is targeted at the endolysosomal pathway but can also be secreted to the extracellular milieu or endocytosed by bystander cells. CstF was shown to be significantly increased in tuberculous pleurisy, and during HIV coinfection, pleural fluids display high viral loads. In human macrophages, our previous results revealed a strong upregulation of CstF in phagocytes activated by interferon γ or after infection with Mycobacterium tuberculosis (Mtb). CstF manipulation using RNA silencing led to increased proteolytic activity of lysosomal cathepsins, improving Mtb intracellular killing. In the present work, we investigate the impact of CstF depletion in macrophages during the coinfection of Mtb-infected phagocytes with lymphocytes infected with HIV. The results indicate that decreasing the CstF released by phagocytes increases the major pro-granzyme convertase cathepsin C of cytotoxic immune cells from peripheral blood-derived lymphocytes. Consequently, an observed augmentation of the granzyme B cytolytic activity leads to a significant reduction in viral replication in HIV-infected CD4+ T-lymphocytes. Ultimately, this knowledge can be crucial for developing new therapeutic approaches to control both pathogens based on manipulating CstF.


Assuntos
Catepsina C , Coinfecção , Granzimas , Infecções por HIV , Macrófagos , Mycobacterium tuberculosis , Humanos , Granzimas/metabolismo , Granzimas/genética , Infecções por HIV/metabolismo , Infecções por HIV/imunologia , Macrófagos/metabolismo , Macrófagos/imunologia , Macrófagos/microbiologia , Macrófagos/virologia , Coinfecção/microbiologia , Catepsina C/metabolismo , Catepsina C/genética , Cistatinas/metabolismo , Cistatinas/genética , Tuberculose/metabolismo , Tuberculose/imunologia , Tuberculose/microbiologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , HIV-1/fisiologia , Biomarcadores Tumorais
15.
Nat Prod Res ; : 1-5, 2024 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-39126707

RESUMO

Asperphenol A (1), a new isoprenyl-phenol-type meroterpenoid, was isolated from the mangrove endophytic fungus Aspergillus sp. GXNU-Y65 together with five known compounds (2-6). All structures were assigned using extensive NMR spectroscopic data and electronic circular dichroism (ECD) calculations. Compounds 1-6 were evaluated for their cytotoxic activity against A549 and T24 human cancer cell lines. Among them, compounds 1 and 5 exhibited moderate inhibitory activities against T24 cancer cell lines with the IC50 values of 26.71 and 43.50 µM, respectively.

16.
Artigo em Inglês | MEDLINE | ID: mdl-39155164

RESUMO

Chemotherapy is the treatment of cancerous cells through the use of cytotoxic drugs. Whilst the use of systemic (intravenous) chemotherapy in equine practice is generally limited to the management of lymphoma, cytotoxic drugs are commonly used in the treatment of accessible skin tumors, either by topical application in the form of ointments or injected intralesionally. These drugs should be employed with caution due to the risk of serious adverse effects. In addition, extreme caution should be followed when preparing, handling, administering, and disposing them, due to their carcinogenic, mutagenic, and teratogenic properties.

17.
Nat Prod Res ; : 1-10, 2024 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-39155512

RESUMO

With the intention of advancing our research on diverse C-20 derivatives of camptothecin (CPT), 38 CPT derivatives bearing sulphonamide and sulfonylurea chemical scaffolds and different substituent groups have been designed, synthesised and evaluated in vitro for cytotoxicity against four tumour cell lines, A-549 (lung carcinoma), KB (nasopharyngeal carcinoma), MDA-MB-231 (triple-negative breast cancer) and KBvin (an MDR KB subiline). As a result, all the synthesised compounds showed promising in vitro cytotoxic activity against the four cancer cell lines tested, and were more potent than irinotecan. Importantly, compounds 12b, 12f, 12j and 13 l possessed better antiproliferative activity against all tested tumour cell lines with IC50 values of 0.0118 - 0.5478 µM, and resulted approximately 3 to 4 times more cytotoxic than topotecan against multidrug-resistant KBvin subline. Convincing evidences are achieved that incorporation of sulphonamide and sulfonylurea motifs into position-20 of camptothecin confers markedly enhanced cytotoxic activity against cancer cell lines.

18.
Front Cell Dev Biol ; 12: 1441381, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39139448

RESUMO

Preparative regimens before Hematopoietic Cell Transplantation (HCT) damage the bone marrow (BM) microenvironment, potentially leading to secondary morbidity and even mortality. The precise effects of cytotoxic preconditioning on bone and BM remodeling, regeneration, and subsequent hematopoietic recovery over time remain unclear. Moreover, the influence of recipient age and cytotoxic dose have not been fully described. In this study, we longitudinally investigated bone and BM remodeling after busulfan treatment with low intensity (LI) and high intensity (HI) regimens as a function of animal age. As expected, higher donor chimerism was observed in young mice in both LI and HI regimens compared to adult mice. Noticeably in adult mice, significant engraftment was only observed in the HI group. The integrity of the blood-bone marrow barrier in calvarial BM blood vessels was lost after busulfan treatment in the young mice and remained altered even 6 weeks after HCT. In adult mice, the severity of vascular leakage appeared to be dose-dependent, being more pronounced in HI compared to LI recipients. Interestingly, no noticeable change in blood flow velocity was observed following busulfan treatment. Ex vivo imaging of the long bones revealed a reduction in the frequency and an increase in the diameter and density of the blood vessels shortly after treatment, a phenomenon that largely recovered in young mice but persisted in older mice after 6 weeks. Furthermore, analysis of bone remodeling indicated a significant alteration in bone turnover at 6 weeks compared to earlier timepoints in both young and adult mice. Overall, our results reveal new aspects of bone and BM remodeling, as well as hematopoietic recovery, which is dependent on the cytotoxic dose and recipient age.

19.
Vet Immunol Immunopathol ; 275: 110814, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39142123

RESUMO

Analysis of the recall response ex vivo in cattle vaccinated with a Mycobacterium avium subsp. paratuberculosis (Map) rel deletion mutant revealed the immune response was directed toward a 35 kD major membrane protein (MMP) of Map. Antigen presenting cells (APC) primed with MMP elicited expansion of CD8 cytotoxic memory T cells (CTL) with ability to kill intracellular bacteria. Development of CTL was MHC-restricted. The gene MAP2121c, encoding MMP, was modified for expression of MMP (tPA-MMP-2mut) in a mammalian cell line to explore the potential of developing MMP as a vaccine. Ex vivo stimulation of PBMC, from Map free cattle, with APC primed with tPA-MMP-2mut expressed p35 elicited a primary CD8 CTL response comparable to the recall response elicited with PBMC from cattle vaccinated with either the Maprel deletion mutant or MMP. In the present study, the modified gene for MMP, now referred to as p35NN, was placed into a bovine herpes virus-4 (BoHV4) vector to determine the potential use of BoHV-4AΔTK-p35NN as a peptide-based vaccine. Subcutaneous vaccination of healthy cattle with BoHV-4AΔTK-p35NN elicited a CTL recall response, as detected ex vivo. The results show use of a virus vector is an effective way for delivery of MMP as a vaccine. The immunogenic activity of MMP was not lost when modified for expression in mammalian cells. The next step is to conduct a field trial to determine if presence of an immune response to MMP prevents Map from establishing an infection.

20.
Beilstein J Org Chem ; 20: 1981-1987, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39161712

RESUMO

Five new ß-alkylpyrrole derivatives, allostreptopyrroles A-E (1-5), were isolated from the culture broth of Allostreptomyces RD068384. Their structures were elucidated by 1D and 2D NMR spectroscopic analyses, HRESIMS, and chemical derivatization. The absolute configurations of compounds 2 and 3 were predicted by comparison of experimental and calculated specific rotation data. Compounds 1-5 are the first examples of natural pyrroles substituted by formyl and carboxyl functionalities. Compounds 1, 4, and 5 showed cytotoxicity against Kasumi-1 human acute myeloblastic leukemia cells with IC50 values of 103, 105, and 105 µM, respectively, which are less active than the anticancer agent cisplatin, with an IC50 value of 70 µM.

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