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1.
Food Chem Toxicol ; 184: 114321, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38072213

RESUMO

Recently, mycotoxin risks in fermented tea have received high attention, but mycotoxin transfer rates from tealeaf to infusion during brewing were rarely considered. In addition, the assessment data (i.e., mycotoxin occurrences and tea consumption) in previous assessments were usually limited. Here, a comprehensive and cumulative risk assessment of aflatoxins and ochratoxin A was performed using a tea assessment model, by which mycotoxin transfer rates were included and the assessment data were collected worldwide. By 10 times of brewing, the aflatoxin transfer rate was only 2.94% and OTA was 63.65%. Besides the extreme case, hazard quotients (HQs) from all consumers were lower than the threshold of 1.0, indicating no noncarcinogenic risk; the P95 cumulative margin of exposure (1/MoET) values were 2.52E-04 (30-39 years of age) and 2.42E-04 (≥50 years of age) for two high exposure groups under the upper bound scenario, which a little higher than the carcinogenic risk threshold of 1.00E-04. Notably, the P95 cumulative 1/MoET values (3.24E-03 -7.95E-03) by food assessment model were ten times higher than those of by tea assessment model. The comparative results showed that mycotoxin dietary risks on tea consumption by food assessment model were much overestimated. The result of this study indicated that the contaminants transfer rates should be considered for risk assessment on tea consumption in future work.


Assuntos
Aflatoxinas , Micotoxinas , Ocratoxinas , Aflatoxinas/toxicidade , Exposição Dietética , Contaminação de Alimentos/análise , Micotoxinas/toxicidade , Micotoxinas/análise , Medição de Risco , Chá
2.
Can J Infect Dis Med Microbiol ; 2022: 6949117, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35228854

RESUMO

AIMS: Current research aimed to explore the therapeutic values of different earthworms as antibacterial, anticoagulant, and antioxidant agents. METHODS: Ten different earthworms, i.e., Amynthas corticis, Amynthas gracilis, Pheretima posthuma, Eisenia fetida, Aporrectodea rosea, Allolobophora chlorotica, Aporrectodea trapezoides, Polypheretima elongata, Aporrectodea caliginosa, and Pheretima hawayana, were collected and screened for biological activities. Antibacterial effect analysis of earthworm species was done against fourteen bacterial pathogens, i.e., Escherichia coli, Serratia marcescens, Streptococcus pyogenes, Staphylococcus epidermidis, Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa (1), Salmonella typhimurium, Shigella flexneri, Enterobacter amnigenus, Serratia odorifera, Pseudomonas aeruginosa (2), Staphylococcus warneri, and Lactobacillus curvatus, via agar well diffusion, crystal violet, MTT, agar disc diffusion, and direct bioautography assays. Antioxidant potential was evaluated through ABTS and DPPH assays. Lipolytic, proteolytic, and amylolytic assays were done for lipase, protease, and amylase enzymes confirmation. In vitro anticoagulant effects were examined in the blood samples by measuring prothrombin time. RESULTS: Results revealed that all earthworm extracts showed the inhibition of all tested bacterial pathogens except P. aeruginosa (1), P. aeruginosa (2), S. warneri, and L. curvatus. The maximum zone of inhibition of E. coli was recorded as 14.66 ± 0.57 mm by A. corticis, 25.0 ± 0.0 mm by P. posthuma, 20.0 ± 0.0 mm by E. fetida, and 20.0 ± 0.0 mm by A. trapezoid. Cell proliferation, biofilm inhibition, the synergistic effect of extracts along with antibiotics, and direct bioautography supported the results of agar well diffusion assay. Similarly, P. hawayana, A. corticis, A. caliginosa, and A. trapezoids increase the prothrombin time more efficiently compared to other earthworms. A. corticis, A. gracilis, A. rosea, A. chlorotica, P. elongata, and A. trapezoides showed maximum DPPH scavenging potential effect. CONCLUSIONS: The coelomic fluid of earthworms possessed several bioactive compounds/enzymes/antioxidants that play an important role in the bacterial inhibition and act as anticoagulant agents. Therefore, the development of new therapeutic drugs from invertebrates could be effective and potential for the prevention of the emergence of multidrug-resistant bacteria.

3.
Angiogenesis ; 23(4): 581-597, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32440964

RESUMO

The liver is a common host organ for cancer, either through lesions that arise in liver epithelial cells [e.g., hepatocellular carcinoma (HCC)] or as a site of metastasis by tumors arising in other organs (e.g., colorectal cancer). However, the changes that occur in liver stromal cells in response to cancer have not been fully characterized, nor has it been determined whether the different sources of liver cancer induce distinct stromal changes. Here, we performed single-cell profiling of liver stromal cells from mouse models of induced spontaneous liver cancer or implanted colorectal liver metastases, with a focus on tumor endothelial cells (ECs). While ECs in liver tissue adjacent to cancerous lesions (so-called adjacent normal) corresponded to liver zonation phenotypes, their transcriptomes were also clearly altered by the presence of a tumor. In comparison, tumor EC transcriptomes show stronger similarities to venous than sinusoidal ECs. Further, tumor ECs, independent of tumor origin, formed distinct clusters displaying conserved "tip-like" or "stalk-like" characteristics, similar to ECs from subcutaneous tumors. However, they also carried liver-specific signatures found in normal liver ECs, suggesting an influence of the host organ on tumor ECs. Our results document gene expression signatures in ECs in liver cancer and show that the host organ, and not the site of tumor origin (liver versus colorectal), is a primary determinant of EC phenotype. In addition, primarily in tumors, we further defined a cluster of chimeric cells that expressed both myeloid and endothelial cell markers and might play a role in tumor angiogenesis.


Assuntos
Quimerismo , Células Endoteliais/patologia , Neoplasias Hepáticas/genética , Análise de Célula Única , Transcriptoma/genética , Animais , Linhagem Celular Tumoral , Humanos , Hidrodinâmica , Fígado/metabolismo , Fígado/patologia , Neoplasias Hepáticas/imunologia , Camundongos Endogâmicos C57BL , Células Mieloides/metabolismo
4.
J Ethnobiol Ethnomed ; 15(1): 6, 2019 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-30691476

RESUMO

BACKGROUND: The ethnic groups in Gilgit-Baltistan have been utilizing local resources in their centuries-old traditional healing system. Most tribes within these ethnic groups still rely on traditional healing systems. We aim to understand the current status, uses, and abundance of medicinal plants, associated traditional knowledge, and trade. MATERIALS AND METHODS: The study incorporated over 300 local community members (70% men and 30% women) in focused group discussions, semi-structured interviews, and homework assignments for 8th to 12th grade students to document traditional knowledge (TK) in six districts in Northeast Pakistan. We calculated various indices such as informant consensus factor, use value, relative frequency of citation, and CoKriging. These indices, along with repetitively used medicinal plants, were used to analyze differences in studied locations. RESULTS: Most of the community members still rely on traditional medication in the study areas. However, we found the highest number of medicinal plants used in Skardu and Gilgit compared to other districts and these two districts also represent trade centers and a highly populated area regarding medicinal plants. Results indicate connection amongst the surveyed villages signifying mixing of knowledge from different sources, with certain areas more influenced by traditional Chinese medicine and others more by Ayurveda and Unani. CONCLUSION: TK is mostly retained with elder community members; however, those directly linked with market value chain retain rich knowledge on traditional use of the medicinal plants from the region. Major trade centers in the region also coincide with a high density of medicinal plant occurrence, knowledge, and higher utilization. Therefore, with the increasing trade in medicinal plant in the region, there is potential for rejuvenation of this knowledge and of plant use in the region.


Assuntos
Comércio , Medicina Tradicional , Plantas Medicinais , Feminino , Grupos Focais , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Entrevistas como Assunto , Masculino , Paquistão
5.
Cancer Res ; 78(9): 2370-2382, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29449267

RESUMO

Angiogenesis involves dynamic interactions between specialized endothelial tip and stalk cells that are believed to be regulated in part by VEGF and Dll4-Notch signaling. However, our understanding of this process is hampered by limited knowledge of the heterogeneity of endothelial cells and the role of different signaling pathways in specifying endothelial phenotypes. Here, we characterized by single-cell transcriptomics the heterogeneity of mouse endothelial cells and other stromal cells during active angiogenesis in xenograft tumors as well as from adult normal heart, following pharmacologic inhibition of VEGF and Dll4-Notch signaling. We classified tumor endothelial cells into three subpopulations that appeared to correspond with tip-like, transition, and stalk-like cells. Previously identified markers for tip and stalk cells were confirmed and several novel ones discovered. Blockade of VEGF rapidly inhibited cell-cycle genes and strongly reduced the proportion of endothelial tip cells in tumors. In contrast, blockade of Dll4 promoted endothelial proliferation as well as tip cell markers; blockade of both pathways inhibited endothelial proliferation but preserved some tip cells. We also phenotypically classified other tumor stromal cells and found that tumor-associated fibroblasts responded to antiangiogenic drug treatments by upregulating hypoxia-associated genes and producing secreted factors involved in angiogenesis. Overall, our findings better define the heterogeneity of tumor endothelial and other stromal cells and reveal the roles of VEGF and Dll4-Notch in specifying tumor endothelial phenotype, highlighting the response of stromal cells to antiangiogenic therapies.Significance: These findings provide a framework for defining subpopulations of endothelial cells and tumor-associated fibroblasts and their rapid changes in gene expression following antiangiogenic treatment. Cancer Res; 78(9); 2370-82. ©2018 AACR.


Assuntos
Células Endoteliais/metabolismo , Neoplasias/genética , Neoplasias/patologia , Neovascularização Patológica/genética , Transcriptoma , Animais , Antineoplásicos/farmacologia , Biomarcadores , Fibroblastos Associados a Câncer/metabolismo , Fibroblastos Associados a Câncer/patologia , Linhagem Celular Tumoral , Modelos Animais de Doenças , Células Endoteliais/patologia , Perfilação da Expressão Gênica , Humanos , Imuno-Histoquímica , Masculino , Camundongos , Neoplasias/metabolismo , Neovascularização Patológica/metabolismo , Análise de Célula Única , Células Estromais/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
6.
J Biomol Struct Dyn ; 35(16): 3449-3468, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27817242

RESUMO

Salmonella typhi, a Gram negative bacterium, has become multidrug resistant (MDR) to wide classes of antibacterials which necessitate an alarming precaution. This study focuses on the binding potential and therapeutic insight of Nano-Fullerene C60 towards virulent targets of Salmonella typhi by computational prediction and preliminary in vitro assays. The clinical isolates of Salmonella typhi were collected and antibiotic susceptibility profiles were assessed. The drug targets of pathogen were selected by rigorous literature survey and gene network analysis by various metabolic network resources. Based on this study, 20 targets were screened and the 3D structures of few drug targets were retrieved from PDB and others were computationally predicted. The structures of nanoleads such as Fullerene C60, ZnO and CuO were retrieved from drug databases. The binding potential of these nanoleads towards all selected targets were predicted by molecular docking. The best docked conformations were screened and concept was investigated by preliminary bioassays. This study revealed that most of the isolates of Salmonella typhi were found to be MDR (p < .05). The theoretical models of selected drug targets showed high stereochemical validity. The molecular docking studies suggested that Fullerene C60 showed better binding affinity towards the drug targets when compared to ZnO and CuO. The preliminary in vitro assays suggested that 100 µg/L Fullerene C60 posses significant inhibitory activities and absence of drug resistance to this nanoparticle. This study suggests that Fullerene C60 can be scaled up as probable lead molecules against the major drug targets of MDR Salmonella typhi.


Assuntos
Antibacterianos/farmacologia , Proteínas de Bactérias/antagonistas & inibidores , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Fulerenos/farmacologia , Nanopartículas/química , Salmonella typhi/efeitos dos fármacos , Antibacterianos/química , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Sítios de Ligação , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Farmacorresistência Bacteriana Múltipla/genética , Fulerenos/química , Redes Reguladoras de Genes , Humanos , Redes e Vias Metabólicas/genética , Simulação de Acoplamento Molecular , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Estrutura Secundária de Proteína , Salmonella typhi/crescimento & desenvolvimento , Salmonella typhi/isolamento & purificação , Salmonella typhi/metabolismo , Homologia Estrutural de Proteína , Febre Tifoide/microbiologia
7.
Cancer Res ; 76(8): 2327-39, 2016 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-26921327

RESUMO

Anti-VEGF therapies benefit several cancer types, but drug resistance that limits therapeutic response can emerge. We generated cell lines from anti-VEGF-resistant tumor xenografts to investigate the mechanisms by which resistance develops. Of all tumor cells tested, only A431 (A431-V) epidermoid carcinoma cells developed partial resistance to the VEGF inhibitor aflibercept. Compared with the parental tumors, A431-V tumors secreted greater amounts of IL6 and exhibited higher levels of phospho-STAT3. Notably, combined blockade of IL6 receptor (IL6R) and VEGF resulted in enhanced activity against A431-V tumors. Similarly, inhibition of IL6R enhanced the antitumor effects of aflibercept in DU145 prostate tumor cells that displays high endogenous IL6R activity. In addition, post hoc stratification of data obtained from a clinical trial investigating aflibercept efficacy in ovarian cancer showed poorer survival in patients with high levels of circulating IL6. These results suggest that the activation of the IL6/STAT3 pathway in tumor cells may provide a survival advantage during anti-VEGF treatment, suggesting its utility as a source of response biomarkers and as a therapeutic target to heighten efficacious results. Cancer Res; 76(8); 2327-39. ©2016 AACR.


Assuntos
Interleucina-6/metabolismo , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Animais , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Xenoenxertos , Humanos , Interleucina-6/antagonistas & inibidores , Camundongos , Receptores de Fatores de Crescimento do Endotélio Vascular , Proteínas Recombinantes de Fusão/farmacologia
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