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1.
Pak J Biol Sci ; 25(8): 765-775, 2022 Jan.
Article in English | MEDLINE | ID: mdl-36098203

ABSTRACT

<b>Background and Objective:</b> Studying the population dynamic of the invasive terrestrial snails as agricultural pests, is essential for designing pest control program to reduce the economic losses to commercial field crops, vegetables and fruits. The population dynamic had been estimated for the three terrestrial snails <i>Theba pisana </i>(Müller, 1774) (Helicidae), <i>Eobania vermiculata </i>(Müller, 1774) (Helicidae) and <i>Monacha obstructa</i> (Pfeiffer, 1842) (Hygromiidae) on orange, apple and mango trees in horticultural fields in two locations. These locations are Nobaria City, Beheira Governorate and Mansouria Village, Giza Governorate. This study carried out during the two consecutive activity seasons September, 2018/August, 2019 and September, 2019/August, 2020. <b>Materials and Methods:</b> The population dynamic, incidence and infestation level of terrestrial snails had been recorded on economic host plants such as fruit trees and other field crops and vegetables. The correlations between climatic factors and the population density of land snails were interpreted by statistical analysis for the two seasons. <b>Results:</b> The population density of terrestrial snails increased gradually after winter to reach its maximum density during spring, while the lowest density was recorded in August. The incidence and infestation level of terrestrial snails varied according to the host plant, climatic factors and locality. <i>Eobania vermiculata</i> were the dominant land snail species in Beheira, while <i>Monacha obstructa</i> infested the majority of the examined fruit trees in Giza. <b>Conclusion:</b> Determining the activity and inactivity periods of land snails through the two seasons and their population dynamic will assist in designing effective control management program to decrease the number of pest and the economic losses of agricultural products.


Subject(s)
Snails , Animals , Egypt , Population Density , Population Dynamics , Seasons
2.
Pak J Biol Sci ; 24(10): 1040-1047, 2021 Jan.
Article in English | MEDLINE | ID: mdl-34842373

ABSTRACT

<b>Background and Objective:</b> Effect of some compounds such as Plant extracts (Techno oil and Berna Star), natural origin compounds (Top-nine, Repcar and Chitosan 5%) and classical chemical pesticides (methomyl and lambda-cyhalothrin) were studied against the terrestrial snail <i>Massylaea vertmiculata</i> using the bait technique. Material and Methods: LC<sub>50</sub> of the each tested compound of natural compounds were estimated after 14 days of treatment, while LC<sub>50</sub> of pesticide were evaluated after 72 hrs of treatment. The impact of LC<sub>50 </sub>of each tested compound on some biochemical parameters, total protein content, alkaline phosphatase (ALP) and acid phosphatase (ACP) activity were determined 48 hrs post treatment. <b>Results:</b> The results revealed that the methomyl and lambda-cyhalothrin were the most effective compounds against test land snails, followed by Repcar, Top-nine and Techno oil, while Berna Star and Nema Ultra Chem come in the last rank. The pesticide compound methomyl was the most toxic one against the tested terrestrial snail species, while the Chitosan 5% was the least toxic one. The results showed that all tested compounds caused fluctuated effect whether increasing or decreasing on all the studies parameters such as total protein content, ALP and ACP activity as well. However, the Techno oil and the Berna Star caused sever decreasing on total protein content and ACP, followed by Top-nine, Repcar, Chitosan 5% (Nema Ultra Chem) and plant extracts. <b>Conclusion:</b> The both tested natural compounds and plant extracts recorded satisfying results compared with methomyl and lambda-cyhalothrin effect and that can be used in the pest controlling programs against terrestrial snails to reduce the environmental pollution.


Subject(s)
Gastropoda/metabolism , Toxicological Phenomena , Animals , Plant Extracts/adverse effects , Plant Extracts/pharmacology , Plant Extracts/therapeutic use
3.
Curr Cancer Drug Targets ; 20(6): 429-460, 2020.
Article in English | MEDLINE | ID: mdl-32321404

ABSTRACT

During the last century, our battle against cancer has been inaugurated upon three main approaches; surgery, radiation and chemotherapy. The latest findings on the effectiveness of immunotherapy in cancer management offer a ray of hope after decades of research and studies on the best treatment methods. Immunotherapy has proven effective in the surveillance and destruction of cancer- causing cells, demonstrating its ability to suppress cancer through controlling the wellestablished immune-editing process. Immuno-editing is a process that comprises three principal elements; elimination, equilibrium, and escape, and is paramount to the comprehension of checkpoint inhibition. Cancer cells employ various approaches to evade the elimination step leading to its immune- escape. The escape mechanism encompasses the up-regulation of negative co-signals that block successful activation of cancer-eradicating immune cells, developing cytokine background that favors the immunosuppressive tumor microenvironment (TME), or dropping the expression of tumor- specific proteins known as neo-antigens, therefore reducing the immunogenic activity against cancer cells. Today, checkpoint inhibitors are considered as a primary approach in our fight against cancer. Strategies targeting the inhibitory roles of checkpoint inhibitors have been shown effective against different cancer types and stages, and some already gained the FDA's approval. This review seeks to comprehensively cover the historical background as well as the most recent updates for the role of immune checkpoint regulators in the maintenance of immune homeostatic balance as well as keeping the tumorigenic cells in check.


Subject(s)
Immune Checkpoint Inhibitors/pharmacology , Immunotherapy/methods , Molecular Targeted Therapy , Neoplasms/drug therapy , Animals , Humans , Neoplasms/immunology
4.
Mol Cancer Ther ; 17(6): 1280-1290, 2018 06.
Article in English | MEDLINE | ID: mdl-29483217

ABSTRACT

BRAFV600E mutations occur in ∼10% of colorectal cancer cases, are associated with poor survival, and have limited responses to BRAF/MEK inhibition with or without EGFR inhibition. There is an unmet need to understand the biology of poor prognostic BRAFMT colorectal cancer. We have used differential gene expression and pathway analyses of untreated stage II and stage III BRAFMT (discovery set: n = 31; validation set: n = 26) colorectal cancer, and an siRNA screen to characterize the biology underpinning the BRAFMT subgroup with poorest outcome. These analyses identified the unfolded protein response (UPR) as a novel and druggable pathway associated with the BRAFMT colorectal cancer subgroup with poorest outcome. We also found that oncogenic BRAF drives endoplasmic reticulum (ER) stress and UPR pathway activation through MEK/ERK. Furthermore, inhibition of GRP78, the master regulator of the UPR, using siRNA or small molecule inhibition, resulted in acute ER stress and apoptosis, in particular in BRAFMT colorectal cancer cells. In addition, dual targeting of protein degradation using combined Carfilzomib (proteasome inhibitor) and ACY-1215 (HDAC6-selective inhibitor) treatment resulted in marked accumulation of protein aggregates, acute ER stress, apoptosis, and therapeutic efficacy in BRAFMT in vitro and xenograft models. Mechanistically, we found that the apoptosis following combined Carfilzomib/ACY-1215 treatment is mediated through increased CHOP expression. Taken together, our findings indicate that oncogenic BRAF induces chronic ER stress and that inducers of acute ER stress could be a novel treatment strategy for poor prognostic BRAFMT colorectal cancer. Mol Cancer Ther; 17(6); 1280-90. ©2018 AACR.


Subject(s)
Colorectal Neoplasms/genetics , Colorectal Neoplasms/metabolism , Mutation , Protein Kinase Inhibitors/pharmacology , Proto-Oncogene Proteins B-raf/antagonists & inhibitors , Proto-Oncogene Proteins B-raf/genetics , Unfolded Protein Response/drug effects , Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Apoptosis/genetics , Biomarkers, Tumor , Cell Line, Tumor , Cell Survival/drug effects , Cell Survival/genetics , Colorectal Neoplasms/drug therapy , Colorectal Neoplasms/mortality , Endoplasmic Reticulum Chaperone BiP , Endoplasmic Reticulum Stress/drug effects , Endoplasmic Reticulum Stress/genetics , Heat-Shock Proteins/genetics , Heat-Shock Proteins/metabolism , Humans , Hydroxamic Acids/pharmacology , MAP Kinase Signaling System , Models, Biological , Oligopeptides/pharmacology , Prognosis , Protein Biosynthesis , Proto-Oncogene Proteins B-raf/metabolism , Pyrimidines/pharmacology , Signal Transduction/drug effects , Transcription Factor CHOP/genetics , Transcription Factor CHOP/metabolism
5.
Oncol Lett ; 14(1): 1035-1040, 2017 Jul.
Article in English | MEDLINE | ID: mdl-28693270

ABSTRACT

Bufadienolides are constituents of the traditional Chinese medicine Chan Su and are found in toad venom. Cardiovascular side-effects are one of the limiting factors towards developing bufadienolides as chemotherapeutic agents. Thus, in the present study, low doses of bufalin and cinobufotalin, prominent members of the bufadienolides, were investigated for their cytotoxic activity in combination with hyperthermia (HT) or radiation (Rad) therapy. In addition, the underlying mechanism involved was investigated. A DNA fragmentation assay, viability assay and microscopic observation were primarily used to assess the effect of low doses of the two drugs in human lymphoma U937 cells. Furthermore, the effects of these drugs on the mitochondrial membrane potential (MMP) and apoptotic-associated protein activation were investigated. HT/bufadienolide- and RT/bufadienolide-treated samples significantly increased the DNA fragmentation percentile and decreased the MMP, as well as increasing the apoptotic features observed microscopically within a relatively short time (6 h) after treatment. The two combinations affected the expression of important apoptotic markers, including caspase-3 and BH3 interacting domain death agonist. The findings of the current study confirm the additive effect of HT with this group of drugs, directing a novel therapeutic avenue for the clinical use of bufadienolides at lower doses with more restrained cardio toxic side-effects.

6.
Chem Biol Interact ; 199(3): 154-60, 2012 Sep 30.
Article in English | MEDLINE | ID: mdl-22898211

ABSTRACT

Cinobufotalin (CB), one of the bufadienolides prepared from toad venom, was investigated for its cytotoxicity, and the underneath mechanism involved. We primarily utilized DNA fragmentation assay and microscopic observation to assess the effect of various doses of CB in human lymphoma U937 cells. Following that, we investigated other parameters involved in cell death mechanism such as reactive oxygen species (ROS), mitochondrial membrane potential (MMP), and apoptotic proteins activation. HeLa cells were concomitantly used to generalize the data observed. Our results show that CB caused significant DNA fragmentation, decrease of MMP, and an increase in the intracellular Ca(2+) ion and ROS production. In addition, CB induced upregulation of Fas protein, proteolytic activation of cytochrome c, caspase-2, -3, -8 and -9 together with the activation of Bid and Bax. Our findings were further validated using either Fas/FasL antagonist or pan-caspase inhibitor to significantly inhibit CB-induced DNA fragmentation. In our study, we suggest that CB induces caspase dependent cell death in U937 cells, and that Fas plays a role in CB-induced apoptosis. Altogether, our data provides novel insights of the mechanism of action of CB and its potential as a future chemotherapeutic agent.


Subject(s)
Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Bufanolides/pharmacology , Amphibian Venoms/chemistry , Animals , Antineoplastic Agents/isolation & purification , Apoptosis/physiology , BH3 Interacting Domain Death Agonist Protein/metabolism , Bufanolides/isolation & purification , Calcium/metabolism , Caspases/metabolism , DNA Fragmentation/drug effects , Drug Screening Assays, Antitumor , HeLa Cells , Humans , Medicine, Chinese Traditional , Membrane Potential, Mitochondrial/drug effects , Metabolic Networks and Pathways , Reactive Oxygen Species/metabolism , U937 Cells , bcl-2-Associated X Protein/metabolism , fas Receptor/metabolism
7.
Int J Hyperthermia ; 28(1): 1-8, 2012.
Article in English | MEDLINE | ID: mdl-22235779

ABSTRACT

Environmental stress induces damage that activates an adaptive response in any organism. The cellular stress response is based on the induction of cytoprotective proteins, the so-called stress or heat shock proteins (HSPs). HSPs are known to function as molecular chaperones which are involved in the therapeutic approach of many diseases. Therefore in the current study we searched nontoxic chaperone inducers in chemical compounds isolated from medicinal plants. Screening of 80 compounds for their Hsp70-inducing activity in human lymphoma U937 cells was performed by western blotting. Five compounds showed significant Hsp70 up-regulation among them shikonin was most potent. Shikonin was able to induce Hsp70 at 0.1 µM after 3 h without activation of heat shock transcription factor 1 (HSF-1). It also induces significant reactive oxygen species generation. The expression level of genes responsive to shikonin was studied using global-scale microarrays and computational gene expression analysis tools. Significant increase in the nuclear factor erythroid 2-related factor 2 (Nrf2, NFEL2L2) -mediated oxidative stress response was observed that leads to the activation of HSP. The results of gene chip analysis were further confirmed by real-time qPCR assay. In short, the detailed mechanisms of Hsp70 induction by shikonin is not fully understood, Nrf2 and its target genes might be involved in the Hsp70 up-regulation in U937 cells.


Subject(s)
Drugs, Chinese Herbal/pharmacology , Heat-Shock Proteins/genetics , Naphthoquinones/pharmacology , Plants, Medicinal , Apoptosis/drug effects , Gene Expression Regulation/drug effects , Heat-Shock Proteins/metabolism , Hot Temperature , Humans , Oligonucleotide Array Sequence Analysis , Reactive Oxygen Species/metabolism , Real-Time Polymerase Chain Reaction , U937 Cells
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