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1.
Fungal Biol ; 128(3): 1771-1779, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38796261

RESUMO

Phaseolus vulgaris L., commonly known as the common bean, is a highly nutritious crop often called the "poor man's meat". However, it is susceptible to various diseases throughout the cropping season, with anthracnose caused by Colletotrichum lindemuthianum being a significant threat that leads to substantial losses. There is still a lack of understanding about the molecular basis of C. lindemuthianum pathogenicity. The first step in understanding this is to identify pathogenicity genes that express more during infection of common beans. A reverse transcription quantitative real-time PCR (qPCR) method can be used for virulence gene expression. However, this approach requires selecting appropriate reference genes to normalize relative gene expression data. Currently, there is no reference gene available for C. lindemuthianum. In this study, we selected eight candidate reference genes from the available genome of C. lindemuthianum to bridge the gap. These genes were ACT (Actin), ß-tub (ß-tubulin), EF (Elongation Factor), Cyt C (Cytochrome C), His H3 (Histone H3), CHS1 (Chitin synthetase), GAPDH (Glyceraldehyde-3-phosphate dehydrogenase) and abfA (Alpha-l-Arabinofuranosidase A). The primers for these candidate reference genes were able to amplify cDNA only from the pathogen, demonstrating their specificity. The qPCR efficiency of the primers ranged from 80% to 103%. We analyzed the stability of gene expression in C. lindemuthianum by exposing the mycelium to nine different stress conditions. We employed algorithms, such as GeNorm, NormFinder, BestKeeper, and RefFinder tools, to identify the most stable gene. The analysis using these tools revealed that EF, GAPDH, and ß-tub most stable genes, while ACT and CHS1 showed relatively low expression stability. A large number of potential effector genes have been identified through bioinformatics analysis in C. lindemuthianum. The stable genes for qPCR (EF and GAPDH) discovered in this study will aid the scientific community in determining the relative expression of C. lindemuthianum effector genes.


Assuntos
Colletotrichum , Phaseolus , Doenças das Plantas , Reação em Cadeia da Polimerase em Tempo Real , Padrões de Referência , Colletotrichum/genética , Phaseolus/microbiologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Reação em Cadeia da Polimerase em Tempo Real/normas , Doenças das Plantas/microbiologia , Perfilação da Expressão Gênica , Genes Fúngicos
2.
Bull Entomol Res ; 114(2): 293-301, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38600043

RESUMO

One of the key reasons for the poor performance of natural enemies of honeydew-producing insect pests is mutualism between ants and some aphid species. The findings demonstrated that red wood ant, Formica rufa Linnaeus (Hymenoptera: Formicidae) had a deleterious impact on different biological parameters of the lady beetle, Hippodamia variegata Goeze (Coleoptera: Coccinellidae). H. variegata laid far fewer eggs in ant-tended aphid colonies, laying nearly 2.5 times more eggs in ant absence. Ants antennated and bit the lady beetle eggs, resulting in significantly low egg hatching of 66 per cent over 85 per cent in ant absent treatments. The presence of ants significantly reduced the development of all larval instars. The highest reduction was found in the fourth larval instar (31.33% reduction), and the lowest in the first larval instar (20% reduction). Later larval instars were more aggressively attacked by ants than earlier instars. The first and second larval instars stopped their feeding and movement in response to ant aggression. The third and fourth larval instars modified their mobility, resulting in increased ant aggression towards them. Adult lady beetles were shown to be more vulnerable to ant attacks than larvae. However, H. variegata adults demonstrated counterattacks in the form of diverse defensive reaction behaviours in response to F. rufa aggression.


Assuntos
Formigas , Besouros , Larva , Animais , Formigas/fisiologia , Besouros/fisiologia , Besouros/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Larva/fisiologia , Afídeos/fisiologia , Agressão , Feminino , Simbiose , Oviposição , Comportamento Predatório
3.
Theor Appl Genet ; 137(1): 32, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38270625

RESUMO

KEY MESSAGE: Mapping and fine mapping of bean anthracnose resistance genes is a continuous process. We report fine mapping of anthracnose resistance gene Co-18 which is the first anthracnose gene mapped to Pv10. The discovery of resistance gene is a major gain in the bean anthracnose pathosystem research. Among the Indian common bean landraces, KRC-5 exhibit high levels of resistance to the bean anthracnose pathogen Colletotrichum lindemuthianum. To precisely map the anthracnose resistance gene, we used a Recombinant Inbred Line (F2:9 RIL) population (KRC-5 × Jawala). The inheritance test revealed that KRC-5 carries a dominant resistance gene temporarily designated as Co-18. We discovered two RAPD markers linked to Co-18 among 287 RAPD markers. These RAPD markers were eventually developed into SCARs (Sc-OPR15 and Sc-OPF6) and flank Co-18 on chromosome Pv10 at a distance of 5.3 and 4.2 cM, respectively. At 4.0-4.1 Mb on Pv10, we detected a SNP (single-nucleotide polymorphism) signal. We synthesized 58 SSRs and 83 InDels from a pool of 135 SSRs and 1134 InDels, respectively. Five SSRs, four InDels, and two SCARs were used to generate the high-density linkage map, which led to the identification of two SSRs (SSR24 and SSR36) that are tightly linked to Co-18. These two SSRs flank the Co-18 to 178 kb genomic region with 13 candidate genes including five NLR (nucleotide-binding and leucine-rich repeat) genes. The closely linked markers SSR24 and SSR36 will be used in cloning and pyramiding of the Co-18 gene with other R genes to develop durable resistant bean varieties.


Assuntos
Phaseolus , Phaseolus/genética , Cicatriz , Técnica de Amplificação ao Acaso de DNA Polimórfico , Mapeamento Cromossômico , Genes Dominantes
4.
Acta Paediatr ; 113(4): 753-760, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38018750

RESUMO

AIM: Implementing the Baby-Friendly Hospital Initiative (BFHI) programme has been fraught with challenges globally. The study aimed to assess the implementation of the BFHI and breastfeeding practices in healthcare facilities in Ogun State, Nigeria. METHODS: It was a questionnaire-based cross-sectional study carried out between August and October 2019 among 100 healthcare workers and 110 mothers from health facilities in Ijebu-Ode Local Government Area of Ogun State, Nigeria. RESULTS: Nearly two-thirds (61.0%) of the healthcare workers were community health workers while the others were nurses. Less than a quarter (23.8%) of the healthcare workers had ever attended breastfeeding educational programmes since they started working. About half of the healthcare workers had good knowledge, attitude and practice of BFHI. Nurses had a significantly better practice of BFHI than community health workers. Understaffing was a major limitation to the implementation of BFHI. The mothers had an exclusive breastfeeding rate of 47%. CONCLUSION: The knowledge, attitude, and practice of BFHI were suboptimal and the exclusive breastfeeding rate among the mothers was low. There is a need to improve staff strength, training and re-training of staff, as well as regular monitoring and evaluation of healthcare facilities on the implementation of BFHI.


Assuntos
Aleitamento Materno , Promoção da Saúde , Feminino , Humanos , Nigéria , Estudos Transversais , Hospitais
5.
Am J Physiol Gastrointest Liver Physiol ; 323(5): G420-G427, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36126221

RESUMO

It has previously been shown that current smoking is protective against endoscopic retrograde cholangiopancreatography (ERCP)-induced acute pancreatitis, but the mechanism of this effect was not identified. We tested the hypothesis that nicotine is the active factor in this protection in a mouse model of ERCP. Pretreatment with nicotine dose dependently inhibited acute pancreatitis caused by infusion of ERCP contrast solution into the main pancreatic duct in mice. 3-2,4-Dimethoxybenzylidene anabaseine (GTS-21), a specific partial agonist of the α7 nicotinic cholinergic receptor (α7nAChR), also protected the pancreas against ERCP-induced acute pancreatitis. The effects of GTS-21 were abolished by pretreatment with the nicotinic receptor antagonist mecamylamine. Surgical splenectomy performed 7 days before ERCP-induced pancreatitis blocked the protective effects of GTS-21. Intravenous injection of a crude preparation of total splenocytes prepared from mice pretreated with GTS-21 inhibited ERCP-induced pancreatitis; splenocytes from mice treated with vehicle had no effect. When T cells were removed from the crude GTS-21-treated splenocyte preparation by immunomagnetic separation, the remaining non-T-cell splenocytes did not protect against ERCP-induced acute pancreatitis. We conclude that nicotine protects against ERCP-induced acute pancreatitis and that splenic T cells are required for this effect. Stimulation of α7 nicotinic cholinergic receptors may protect against ERCP-induced acute pancreatitis and may also be a novel approach to therapeutic reversal of ongoing acute pancreatitis.NEW & NOTEWORTHY Epidemiological evidence indicated that acute smoking reduced the risk of endoscopic retrograde cholangiopancreatography (ERCP)-induced pancreatitis, but the mechanism has remained elusive. The current findings indicate the nicotine reduces the severity of ERCP-induced pancreatitis by stimulating a population of splenic T cells that exert a protective effect on the pancreas. These findings raise the possibility that nicotinic agonists might be useful in treating pancreatitis.


Assuntos
Colangiopancreatografia Retrógrada Endoscópica , Pancreatite , Camundongos , Animais , Colangiopancreatografia Retrógrada Endoscópica/efeitos adversos , Pancreatite/etiologia , Nicotina , Mecamilamina , Agonistas Nicotínicos/farmacologia , Doença Aguda , Receptor Nicotínico de Acetilcolina alfa7 , Baço , Linfócitos T
6.
Front Oncol ; 12: 919351, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35912187

RESUMO

Genetic instabilities exacerbated by the dysfunction of telomeres can lead to the development of cancer. Nearly 90% of all human malignancies are linked with telomere dysregulation and overexpression of telomerase, an enzyme that catalyzes the synthesis of telomeric DNA repeats at the ends of chromosomes. The burden of gastric cancer continues to inflict a deterring impact on the global health scenario, accounting for over one million new cases in 2020. The disease is asymptomatic in its early stages of progression, which is attributed to the poor prognosis and overall surge in mortality rate worldwide. Exploiting telomere physiology can provide extensive mechanistic insight into telomere-associated gastric cancer progression and its use as a target in a variety of therapeutic interventions. In this study, we aimed to evaluate the clinical implications of c-Myc, human telomerase reverse transcriptase (hTERT) expression, and telomere length in patients with gastric cancer. A total of 57 gastric cancer cases and adjacent controls were included in the study. RT-PCR and immunohistochemistry were used to assess the expression levels of c-Myc and hTERT. The relative telomere length was measured by MMQPCR using the Cawthon method. Our results indicated that the shorter telomere and increased hTERT expression were associated with gastric cancer progression. The study also highlighted the role of short telomeres and increased expression of hTERT in gastric cancer progression and its association with various etiological risk factors, transcriptional activators, and overall survival among the ethnic Kashmiri population of North India.

7.
Inquiry ; 59: 469580221093442, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35613600

RESUMO

The novel coronavirus pandemic has led to morbidity and mortality throughout the world. Until now, it is a highly virulent contagion attacking the respiratory system in humans, especially people with chronic diseases and the elderly who are most vulnerable. A majority of afflicted are those suffering from cardiovascular and coronary diseases. In this review article, an attempt has been made to discuss and thoroughly review the mode of therapies that alleviate cardiac complications and complications due to hypercoagulation in patients infected with the SARS-CoV-2 virus. Presently a host of thrombolytic drugs are in use like Prourokinase, Retelapse, RhTNK-tPA and Urokinase. However, thrombolytic therapy, especially if given intravenously, is associated with a serious risk of intracranial haemorrhage, systemic haemorrhage, immunologic complications, hypotension and myocardial rupture. The effects of the SARS-CoV-2 virus upon the cardiovascular system and coagulation state of the body are being closely studied. In connection to the same, clinical prognosis and complications of thrombolytic therapy are being scrutinized. It is noteworthy to mention that myocardial oxygen supply/demand mismatch, direct myocardial cells injury and acute plaque rupture are the multiple mechanisms responsible for acute coronary syndrome and cardiac complications in Covid-19 infection. However, this review has limitations as data available in this context is limited, scattered and heterogenous that questions the reliability of the same. So, more multi-centric studies involving representative populations, carried out meticulously, could further assist in responding better to cardiac complications among Covid-19 patients.


Assuntos
COVID-19 , Doenças Cardiovasculares , Sistema Cardiovascular , Idoso , Doenças Cardiovasculares/tratamento farmacológico , Humanos , Reprodutibilidade dos Testes , SARS-CoV-2
8.
Front Pharmacol ; 13: 821344, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35401182

RESUMO

JAK/STAT signaling pathway is one of the important regulatory signaling cascades for the myriad of cellular processes initiated by various types of ligands such as growth factors, hormones, and cytokines. The physiological processes regulated by JAK/STAT signaling are immune regulation, cell proliferation, cell survival, apoptosis and hematopoiesis of myeloid and non-myeloid cells. Dysregulation of JAK/STAT signaling is reported in various immunological disorders, hematological and other solid malignancies through various oncogenic activation mutations in receptors, downstream mediators, and associated transcriptional factors such as STATs. STATs typically have a dual role when explored in the context of cancer. While several members of the STAT family are involved in malignancies, however, a few members which include STAT3 and STAT5 are linked to tumor initiation and progression. Other STAT members such as STAT1 and STAT2 are pivotal for antitumor defense and maintenance of an effective and long-term immune response through evolutionarily conserved programs. The effects of JAK/STAT signaling and the persistent activation of STATs in tumor cell survival; proliferation and invasion have made the JAK/STAT pathway an ideal target for drug development and cancer therapy. Therefore, understanding the intricate JAK/STAT signaling in the pathogenesis of solid malignancies needs extensive research. A better understanding of the functionally redundant roles of JAKs and STATs may provide a rationale for improving existing cancer therapies which have deleterious effects on normal cells and to identifying novel targets for therapeutic intervention in solid malignancies.

9.
Am J Physiol Gastrointest Liver Physiol ; 322(6): G561-G570, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35293263

RESUMO

Proper mitochondrial function and adequate cellular ATP are necessary for normal pancreatic protein synthesis and sorting, maintenance of intracellular organelles and enzyme secretion. Inorganic phosphate is required for generating ATP and its limited availability may lead to reduced ATP production causing impaired Ca2+ handling, defective autophagy, zymogen activation, and necrosis, which are all features of acute pancreatitis. We hypothesized that reduced dietary phosphate leads to hypophosphatemia and exacerbates pancreatitis severity of multiple causes. We observed that mice fed a low-phosphate diet before the induction of pancreatitis by either repeated caerulein administration or pancreatic duct injection as a model of pressure-induced pancreatitis developed hypophosphatemia and exhibited more severe pancreatitis than normophosphatemic mice. Pancreatitis severity was significantly reduced in mice treated with phosphate. In vitro modeling of secretagogue- and pressure-induced pancreatic injury was evaluated in isolated pancreatic acini using cholecystokinin and the mechanoreceptor Piezo1 agonist, Yoda1, under low and normal phosphate conditions. Isolated pancreatic acini were more sensitive to cholecystokinin- and Yoda1-induced acinar cell damage and mitochondrial dysfunction under low-phosphate conditions and improved following phosphate supplementation. Importantly, even mice on a normal phosphate diet exhibited less severe pancreatitis when treated with supplemental phosphate. Thus, hypophosphatemia sensitizes animals to pancreatitis and phosphate supplementation reduces pancreatitis severity. These appear to be direct effects of phosphate on acinar cells through restoration of mitochondrial function. We propose that phosphate administration may be useful in the treatment of acute pancreatitis.NEW & NOTEWORTHY Impaired ATP synthesis disrupts acinar cell homeostasis and is an early step in pancreatitis. We report that reduced phosphate availability impairs mitochondrial function and worsens pancreatic injury. Phosphate supplementation improves mitochondrial function and protects against experimental pancreatitis, raising the possibility that phosphate supplementation may be useful in treating pancreatitis.


Assuntos
Hipofosfatemia , Pancreatite , Doença Aguda , Trifosfato de Adenosina/metabolismo , Animais , Ceruletídeo/farmacologia , Colecistocinina/metabolismo , Hipofosfatemia/metabolismo , Canais Iônicos/metabolismo , Camundongos , Pâncreas/metabolismo , Pancreatite/induzido quimicamente , Pancreatite/tratamento farmacológico , Pancreatite/metabolismo , Fosfatos/metabolismo
10.
Gastroenterology ; 161(3): 982-995.e2, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34051238

RESUMO

BACKGROUND & AIMS: Heavy alcohol consumption is a common cause of acute pancreatitis; however, alcohol abuse does not always result in clinical pancreatitis. As a consequence, the factors responsible for alcohol-induced pancreatitis are not well understood. In experimental animals, it has been difficult to produce pancreatitis with alcohol. Clinically, alcohol use predisposes to hypophosphatemia, and hypophosphatemia has been observed in some patients with acute pancreatitis. Because of abundant protein synthesis, the pancreas has high metabolic demands, and reduced mitochondrial function leads to organelle dysfunction and pancreatitis. We proposed, therefore, that phosphate deficiency might limit adenosine triphosphate synthesis and thereby contribute to alcohol-induced pancreatitis. METHODS: Mice were fed a low-phosphate diet (LPD) before orogastric administration of ethanol. Direct effects of phosphate and ethanol were evaluated in vitro in isolated mouse pancreatic acini. RESULTS: LPD reduced serum phosphate levels. Intragastric administration of ethanol to animals maintained on an LPD caused severe pancreatitis that was ameliorated by phosphate repletion. In pancreatic acinar cells, low-phosphate conditions increased susceptibility to ethanol-induced cellular dysfunction through decreased bioenergetic stores, specifically affecting total cellular adenosine triphosphate and mitochondrial function. Phosphate supplementation prevented ethanol-associated cellular injury. CONCLUSIONS: Phosphate status plays a critical role in predisposition to and protection from alcohol-induced acinar cell dysfunction and the development of acute alcohol-induced pancreatitis. This finding may explain why pancreatitis develops in only some individuals with heavy alcohol use and suggests a potential novel therapeutic approach to pancreatitis. Finally, an LPD plus ethanol provides a new model for studying alcohol-associated pancreatic injury.


Assuntos
Metabolismo Energético , Hipofosfatemia/complicações , Mitocôndrias/metabolismo , Pâncreas/metabolismo , Pancreatite Alcoólica/metabolismo , Fosfatos/deficiência , Trifosfato de Adenosina/metabolismo , Animais , Modelos Animais de Doenças , Etanol , Hipofosfatemia/metabolismo , Hipofosfatemia/prevenção & controle , Masculino , Camundongos Endogâmicos C57BL , Mitocôndrias/patologia , Pâncreas/patologia , Pancreatite Alcoólica/induzido quimicamente , Pancreatite Alcoólica/patologia , Pancreatite Alcoólica/prevenção & controle , Fosfatos/administração & dosagem , Índice de Gravidade de Doença , Técnicas de Cultura de Tecidos
11.
J Appl Microbiol ; 131(1): 124-134, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33251642

RESUMO

AIMS: Conventional antibiotics have been failed to treat infectious diseases due to emergence of multidrug resistance (MDR) in some common pathogens. The current study aimed to formulate new antimicrobials from greener sources. In the midst of these efforts, nanotechnology is a newly emerged field, in which the synthesis of new nanoparticles through novel and efficient means is on the rise. METHODS AND RESULTS: The current work has been carried out to assess the potential of Fraxinus xanthoxyloides (FX) leaf extract in biosynthesis of silver nanoparticles (FX-AgNPs). This method is economical and simple one-step approach to synthesize AgNPs. Characterization of FX-AgNPs has been done by UV-Visible spectroscopy, scanning electron microscope (SEM), X-ray diffraction (XRD), transmission electronic microscope (TEM) and Fourier transforms infrared spectroscopy (FT-IR). The formation of FX-AgNPs has confirmed through UV-Visible spectroscopy (at 430 nm) by change of colour owing to surface Plasmon resonance. Based on the XRD pattern, the crystalline property of FX-AgNPs has established. Functional groups existing in F. xanthoxyloides leaf extract are confirmed by FT-IR spectrum. SEM and TEM authenticated morphology of the AgNPs. The newly synthesized nanoparticles were evaluated for their antimicrobial potential. Minimum inhibitory concentration was determined against Escherichia coli, methicillin-resistant Staphylococcus aureus (MRSA) strains, Pseudomonas aeruginosa and Candida albicans by microtiter plate assay. The lowest inhibition (69%) observed against MRSA was at a concentration of 50 ppm FX-AgNPs and maximum inhibition (81%) observed was against P. aeruginosa. The biosynthesized AgNPs triggered up to 68·6% reduction of the P. aeruginosa biofilm when compared to the control. CONCLUSION: It can be concluded that nanoparticles could be a better alternative of antibiotics with greater efficacies and represent a valuable milestone to fight against infections caused by MDR pathogens. SIGNIFICANCE AND IMPACT OF THE STUDY: This study imparts a useful insight into the development of a new antimicrobial agent from a novel source.


Assuntos
Anti-Infecciosos/farmacologia , Fraxinus/química , Nanopartículas Metálicas/química , Extratos Vegetais/química , Prata/farmacologia , Anti-Infecciosos/química , Bactérias/classificação , Bactérias/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Resistência Microbiana a Medicamentos/efeitos dos fármacos , Química Verde , Testes de Sensibilidade Microbiana , Folhas de Planta/química , Prata/química
12.
Mutat Res Rev Mutat Res ; 785: 108321, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32800272

RESUMO

BRAF is a member of the RAF family of serine/threonine-specific protein kinases. Oncogenic BRAF, in particular, BRAF V600E, can disturb the normal protein folding machinery in the endoplasmic reticulum (ER) leading to accumulation of unfolded/misfolded proteins in the ER lumen, a condition known as endoplasmic reticulum (ER) stress. To alleviate such conditions, ER-stressed cells have developed a highly robust and adaptable signaling network known as unfolded protein response (UPR). UPR is ordinarily a cytoprotective response and usually operates through the induction of autophagy, an intracellular lysosomal degradation pathway that directs damaged proteins, protein aggregates, and damaged organelles for bulk degradation and recycling. Both ER stress and autophagy are involved in the progression and chemoresistance of melanoma. Melanoma, which arises as a result of malignant transformation of melanocytes, exhibits exceptionally high therapeutic resistance. Many mechanisms of therapeutic resistance have been identified in individual melanoma patients and in preclinical BRAF-driven melanoma models. Recently, it has been recognized that oncogenic BRAF interacts with GRP78 and removes its inhibitory influence on the three fundamental ER stress sensors of UPR, PERK, IRE1α, and ATF6. Dissociation of GRP78 from these ER stress sensors prompts UPR that subsequently activates cytoprotective autophagy. Thus, pharmacological inhibition of BRAF-induced ER stress-mediated autophagy can potentially resensitize BRAF mutant melanoma tumors to apoptosis. However, the underlying molecular mechanism of how oncogenic BRAF elevates the basal level of ER stress-mediated autophagy in melanoma tumors is not well characterized. A better understanding of the crosstalk between oncogenic BRAF, ER stress and autophagy may provide a rationale for improving existing cancer therapies and identify novel targets for therapeutic intervention of melanoma.


Assuntos
Autofagia , Resistencia a Medicamentos Antineoplásicos , Estresse do Retículo Endoplasmático , Melanoma/genética , Proteínas Proto-Oncogênicas B-raf/genética , Neoplasias Cutâneas/genética , Resposta a Proteínas não Dobradas , Apoptose , Chaperona BiP do Retículo Endoplasmático , Humanos , Melanoma/tratamento farmacológico , Transdução de Sinais , Neoplasias Cutâneas/tratamento farmacológico , Melanoma Maligno Cutâneo
13.
Heliyon ; 6(6): e04209, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32613108

RESUMO

AIMS: Ocimum viride Willd. (family: Lamiaceae) is a member of the genus Ocimum, an aromatic annual and perennial herb with numerous culinary, horticultural and ethno-medicinal benefits. This study aims to explore the chemical properties of leaf essential oil (EO) from Ocimum viride and to evaluate its antimicrobial and anticancer potential. MAIN METHODS: Characterization of essential oil was done by GCMS, antimicrobial by agar well diffusion methods, in vitro cytotoxicity evaluation by MTT assay, cell death analysis was done by DNA fragmentation, cell cycle analysis, nuclear morphology analysis and molecular docking studies were also conducted. KEY FINDINGS: Essential oil from aerial parts (leaf) of Ocimum viride revealed high content of oxygenated monoterpenes, notably thymol (~50%) and γ-terpinene (~18%). Further, antibacterial analysis showed that among all the evaluated bacterial species EO showed highest sensitivity against the Bacillus subtilis and was also found most effective against HT-29 colon cancer cell line with IC50 value of ~0.034 ± 0.001µL/mL. Mechanistic studies revealed that EO inhibits the growth of HT-29 colon cancer cells probably through induction of irreparable DNA damage leading to subsequent cell death in apoptotic manner. Molecular docking analysis also supports the in vitro studies conducted by indicating the interaction of thymol with Sec A protein of Bacillus subtilis cell wall as well as with Beclin protein responsible for apoptotic corpse clearance. SIGNIFICANCE: Taken together, our results indicate that EO possesses potent antimicrobial and anticancer properties, and may find applications as effective antibacterial and in cancer therapeutics.

14.
Sci Rep ; 10(1): 9767, 2020 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-32555208

RESUMO

The magnetisation reversal behaviour as a function of composition was studied in low rare earth concentration alloys. 30 nm thick rare earth:transition-metal films of composition GdxCo100-x, GdxFe100-x and Gdx(Co50Fe50)100-x were prepared by magnetron sputtering, where x ranged from 4 to 13 atomic%. Magnetisation behaviour was studied using MOKE and Hall hysteresis measurements. The magnetic reversal behaviour as a function of Gd content is strongly dependent on the transition metal. With increasing Gd content the film structure transitions from crystalline to amorphous and the saturation magnetisation decreases linearly. For GdCo, the reversal field, Hc, increases by less than a factor of two with Gd doping of 11%, while for Fe, the coercivity falls by a factor of ten with 8% Gd. This may be attributed to changes in the crystalline morphology. GdCoFe shows a similar trend with Gd doping for the in-plane reversal field to that of GdFe. With 13% Gd in Fe there is evidence indicating the presence of a weak perpendicular magnetic anisotropy, PMA. With Gd doping the anomalous Hall resistivity of Co, Fe and CoFe increases significantly with the largest increase observed for GdCoFe.

15.
J Clin Invest ; 130(5): 2527-2541, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-31999644

RESUMO

Elevated pressure in the pancreatic gland is the central cause of pancreatitis following abdominal trauma, surgery, endoscopic retrograde cholangiopancreatography, and gallstones. In the pancreas, excessive intracellular calcium causes mitochondrial dysfunction, premature zymogen activation, and necrosis, ultimately leading to pancreatitis. Although stimulation of the mechanically activated, calcium-permeable ion channel Piezo1 in the pancreatic acinar cell is the initial step in pressure-induced pancreatitis, activation of Piezo1 produces only transient elevation in intracellular calcium that is insufficient to cause pancreatitis. Therefore, how pressure produces a prolonged calcium elevation necessary to induce pancreatitis is unknown. We demonstrate that Piezo1 activation in pancreatic acinar cells caused a prolonged elevation in intracellular calcium levels, mitochondrial depolarization, intracellular trypsin activation, and cell death. Notably, these effects were dependent on the degree and duration of force applied to the cell. Low or transient force was insufficient to activate these pathological changes, whereas higher and prolonged application of force triggered sustained elevation in intracellular calcium, leading to enzyme activation and cell death. All of these pathological events were rescued in acinar cells treated with a Piezo1 antagonist and in acinar cells from mice with genetic deletion of Piezo1. We discovered that Piezo1 stimulation triggered transient receptor potential vanilloid subfamily 4 (TRPV4) channel opening, which was responsible for the sustained elevation in intracellular calcium that caused intracellular organelle dysfunction. Moreover, TRPV4 gene-KO mice were protected from Piezo1 agonist- and pressure-induced pancreatitis. These studies unveil a calcium signaling pathway in which a Piezo1-induced TRPV4 channel opening causes pancreatitis.


Assuntos
Canais Iônicos/agonistas , Pancreatite/etiologia , Pancreatite/fisiopatologia , Canais de Cátion TRPV/fisiologia , Células Acinares/efeitos dos fármacos , Células Acinares/patologia , Células Acinares/fisiologia , Animais , Cálcio/metabolismo , Sinalização do Cálcio , Morte Celular , Modelos Animais de Doenças , Feminino , Canais Iônicos/genética , Canais Iônicos/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Modelos Biológicos , Pâncreas/efeitos dos fármacos , Pâncreas/patologia , Pâncreas/fisiopatologia , Pancreatite/patologia , Pressão , Pirazinas/farmacologia , Canais de Cátion TRPV/deficiência , Canais de Cátion TRPV/genética , Tiadiazóis/farmacologia
16.
Front Oncol ; 10: 604747, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33569347

RESUMO

Helicobacter pylori infection has been associated with the onset of gastric mucosal inflammation and is known to perturb the balance between T-regulatory (Treg) and T-helper 17 (Th17) cells which causes a spurt of interleukin 17 (IL17) and transforming growth factor-ß (TGF-ß) from Th17 and Treg cells within the gastric milieu. IL17 instigates a surge of interleukin 6 (IL6) from T-helper 1 (Th1) and T-helper 2 (Th2) cells. Further, H. pylori infection is known to stimulate the atypical DNA methylation in gastric mucosa. However, the precise role of cytokine signaling in induction of epigenetic modifications during gastric carcinogenesis is vaguely understood. In this study, patient samples from were examined using real-time polymerase chain reaction (qPCR), PCR, methylation-specific (MS)-PCR, and enzyme-linked immunosorbent assays. We found that H. pylori infection augments the production of interleukin 10 (IL10), IL6, and TGF-ß in the gastric milieu and systemic circulation. Together with the IL6/IL10 mediated hyperactivation of the JAK/STAT pathway, H. pylori infection causes the inactivation of suppressor of cytokine signaling 1 (SOCS1) gene through the hypermethylation of the promoter region. This study signifies that H. pylori-mediated epigenetic silencing of SOCS1 in concert with inflammatory cytokines miffs hyperactivation of the JAK/STAT cascade during gastric carcinogenesis.

17.
Cancer Med ; 9(24): 9181-9192, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-31568659

RESUMO

Cancer is a life-threatening disease afflicting human health worldwide. Recent advances in drug discovery infrastructure and molecular approaches have helped a lot in identifying the novel drug targets for therapeutic intervention. Nevertheless, the morbidity and mortality rates because of this disease keep on rising at an alarming rate. Recently, the use of natural and synthetic molecules as innovative therapeutic tools for cancer prevention has lead to the development of cancer chemoprevention. Cancer chemoprevention is a prophylactic strategy that involves the chronic administration of one or more natural or synthetic agents to block, to inhibit, or to suppress the process of cancer development before it becomes an invasive disease. Quercetin, a dietary bioflavonoid, can specifically retard the growth of cancer cells and behaves as a potent cancer chemopreventive agent. Quercetin has multiple intracellular targets in a cancer cell. Therefore, many mechanisms have been postulated to explain its chemopreventive action. The chemopreventive effects elicited by this natural molecule in different model systems are believed to include antioxidant/pro-oxidant action, regulation of redox homeostasis, apoptosis, cell cycle arrest, anti-inflammatory action, modulation of drug metabolizing enzymes, alterations in gene expression patterns, inhibition of Ras gene expression, and modulation of signal transduction pathways. However, cell signaling networks have recently garnered attention as common molecular target for various chemopreventive effects of quercetin. In this review, we made an attempt to critically summarize the emerging knowledge on the role of quercetin in cancer chemoprevention and the underlying molecular mechanisms implicated in its chemopreventive and therapeutic effects.


Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Quimioprevenção/métodos , Flavonoides/farmacologia , Neoplasias/prevenção & controle , Quercetina/farmacologia , Animais , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/patologia , Transdução de Sinais
18.
Nat Commun ; 9(1): 1715, 2018 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-29712913

RESUMO

Merely touching the pancreas can lead to premature zymogen activation and pancreatitis but the mechanism is not completely understood. Here we demonstrate that pancreatic acinar cells express the mechanoreceptor Piezo1 and application of pressure within the gland produces pancreatitis. To determine if this effect is through Piezo1 activation, we induce pancreatitis by intrapancreatic duct instillation of the Piezo1 agonist Yoda1. Pancreatitis induced by pressure within the gland is prevented by a Piezo1 antagonist. In pancreatic acinar cells, Yoda1 stimulates calcium influx and induces calcium-dependent pancreatic injury. Finally, selective acinar cell-specific genetic deletion of Piezo1 protects mice against pressure-induced pancreatitis. Thus, activation of Piezo1 in pancreatic acinar cells is a mechanism for pancreatitis and may explain why pancreatitis develops following pressure on the gland as in abdominal trauma, pancreatic duct obstruction, pancreatography, or pancreatic surgery. Piezo1 blockade may prevent pancreatitis when manipulation of the gland is anticipated.


Assuntos
Células Acinares/efeitos dos fármacos , Cálcio/metabolismo , Canais Iônicos/genética , Mecanotransdução Celular/efeitos dos fármacos , Pâncreas/efeitos dos fármacos , Pancreatite/prevenção & controle , Células Acinares/metabolismo , Células Acinares/patologia , Animais , Modelos Animais de Doenças , Expressão Gênica , Humanos , Pressão Hidrostática/efeitos adversos , Peptídeos e Proteínas de Sinalização Intercelular , Canais Iônicos/agonistas , Canais Iônicos/antagonistas & inibidores , Canais Iônicos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pâncreas/metabolismo , Pâncreas/patologia , Pancreatite/etiologia , Pancreatite/genética , Pancreatite/patologia , Peptídeos/farmacologia , Cultura Primária de Células , Bibliotecas de Moléculas Pequenas/farmacologia , Venenos de Aranha/farmacologia
19.
Front Cell Dev Biol ; 6: 10, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29497610

RESUMO

Cancer is a genetic disease characterized by unregulated growth and dissemination of malignantly transformed neoplastic cells. The process of cancer development goes through several stages of biochemical and genetic alterations in a target cell. Several dietary alkaloids have been found to inhibit the molecular events and signaling pathways associated with various stages of cancer development and therefore are useful in cancer chemoprevention. Cancer chemoprevention has long been recognized as an important prophylactic strategy to reduce the burden of cancer on health care system. Cancer chemoprevention assumes the use of one or more pharmacologically active agents to block, suppress, prevent, or reverse the development of invasive cancer. Piperine is an active alkaloid with an excellent spectrum of therapeutic activities such as anti-oxidant, anti-inflammatory, immunomodulatory, anti-asthmatic, anti-convulsant, anti-mutagenic, antimycobacterial, anti-amoebic, and anti-cancer activities. In this article, we made an attempt to sum up the current knowledge on piperine that supports the chemopreventive potential of this dietary phytochemical. Many mechanisms have been purported to understand the chemopreventive action of piperine. Piperine has been reported to inhibit the proliferation and survival of many types of cancer cells through its influence on activation of apoptotic signaling and inhibition of cell cycle progression. Piperine is known to affect cancer cells in variety of other ways such as influencing the redox homeostasis, inhibiting cancer stem cell (CSC) self-renewal and modulation of ER stress and autophagy. Piperine can modify activity of many enzymes and transcription factors to inhibit invasion, metastasis, and angiogenesis. Piperine is a potent inhibitor of p-glycoprotein (P-gp) and has a significant effect on the drug metabolizing enzyme (DME) system. Because of its inhibitory influence on P-gp activity, piperine can reverse multidrug resistance (MDR) in cancer cells and acts as bioavailability enhancer for many chemotherapeutic agents. In this article, we emphasize the potential of piperine as a promising cancer chemopreventive agent and the knowledge we collected in this review can be applied in the strategic design of future researches particularly human intervention trials with piperine.

20.
Dermatitis ; 26(3): 136-41, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25984690

RESUMO

BACKGROUND: Saffron, a bulbous perennial plant belonging to Iridaceae family, is the most expensive cultivated herb that is widely used for industrial and nonindustrial purposes. However, besides its attractive and valuable properties, contact dermatitis due to saffron is an uncommon reported entity. OBJECTIVES: The aims of this study were to determine the clinical pattern patch-testing profile of contact dermatitis in saffron workers and to identify the most common allergens/sensitizers. MATERIAL AND METHODS: One hundred ten saffron workers were patch-tested with 39 allergens, which included Indian standard series antigens, plant series antigens, and extracts from different parts of saffron flower. RESULTS: The allergens in Indian standard series accounted for 52.44% of positive reactions. Plant series and different parts of saffron accounted for 47.56% of the positive reactions. Among those patients with positive responses to the supplemental saffron allergens, 83.3% were of present or past relevance. CONCLUSIONS: The data observed in the present study confirm that the saffron dermatitis is a distinct clinical entity with characteristic clinical presentation and has a strong significance as an occupational allergen in those handling this plant. Patch testing with different parts of saffron flower has a role to play in finding out the etiological cause.


Assuntos
Crocus/efeitos adversos , Dermatite Alérgica de Contato/etiologia , Dermatite Ocupacional/etiologia , Flores/efeitos adversos , Indústria de Processamento de Alimentos , Dermatoses da Mão/etiologia , Adulto , Alérgenos/efeitos adversos , Estudos de Casos e Controles , Crocus/imunologia , Dermatite Alérgica de Contato/imunologia , Dermatite Ocupacional/imunologia , Feminino , Flores/imunologia , Dermatoses da Mão/imunologia , Humanos , Índia , Masculino , Pessoa de Meia-Idade , Testes do Emplastro
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