232 research outputs found
Investigation of Lethal And Sub-Lethal Effects of Common Insecticides, Fipronil and Imidacloprid, on Juvenile Brown Shrimp, Farfantepenaeus aztecus, and White Shrimp, Litopenaeus setiferus
Chemical pesticides are widely used around the world, but at the same time, they may pose direct or indirect risks to many non-target organisms. Recent increased use of insecticides in coastal areas to control invasive species raises concern that insecticides may affect ecologically and/or commercially important species found in estuaries. In this study, a series of laboratory experiments was conducted to evaluate short-term (lethal) and long-term (sub-lethal) effects of fipronil and imidacloprid on juveniles of brown shrimp and white shrimp. Various concentrations of fipronil and imidacloprid in each experiment were used. The concentrations were determined based on previously observed concentrations in the aquatic environment by other researchers. In the first experiment, five nominal concentrations of fipronil (0.1, 1.0, 3.0, 6.4, and 10.0 μg/L) were used; whereas, in the second and third experiments, lower concentrations of fipronil (0.005, 0.01, 0.1, 1.0, and 3.0 μg/L) and five nominal concentrations of imidacloprid (0.5, 1.0, 15.0, 34.5, 320.0 μg/L) were used. The endpoints of the studies were survivorship, the nominal median lethal concentration (LC50), the nominal median lethal time (LT50), development (weight gain and inter-molt intervals), behavioral and physical changes, and whole-body chemical composition. The main results were as following: (1) Both insecticides affected brown shrimp and white shrimp growth, survival, body composition, body color, and behavior in a concentration-dependent manner; (2) Brown shrimp juveniles were more sensitive to fipronil exposure than white shrimp, with 96-hour LC50 = 0.12 μg/L, which makes brown shrimp one of the most sensitive invertebrates to fipronil studied so far; (3) Under their environmental concentrations, fipronil showed higher impact on juvenile brown shrimp compared with imidacloprid; (4) Fipronil and imidacloprid caused noticeable sub-lethal effects to brown shrimp and white shrimp at concentrations lower than their chronic levels in the aquatic life benchmark of the U.S. EPA. Our results suggest that monitoring of fipronil and imidacloprid should be recommended in estuaries and other areas along the coast near the locations where either fipronil or imidacloprid is used. In addition, it is of importance to reduce the usage of these insecticides especially during the seasons of penaeid shrimp migration to inshore annual nursery areas. Revising the acute and chronic levels of the U.S. EPA aquatic life benchmarks for fipronil and imidacloprid is also recommended to improve the health of estuaries and increase the abundance of shrimp populations in the Gulf of Mexico region
Decay Rates of Plasmonic Elliptical Nanostructures via Effective Medium Theory
This paper investigates the spontaneous decay rate of elliptical plasmonic nanostructures. The refractive index was analyzed using the effective medium theory (EMT). Then, the polarizability, spontaneous radiative, non-radiative decay rate, and electric field enhancement factor were characterized for the targeted elliptical nanostructures at different aspect ratios. All of the optical analyses were analyzed at different distances between the excited fluorescent coupled atom and the plasmonic nanostructure (down to 100 nm). This work is promising in selecting the optimum elliptical nanostructure according to the required decay rates for optical conversion efficiency control in energy harvesting for solar cells and optical sensing applications
Marjoram Relaxes Rat Thoracic Aorta Via a PI3-K/eNOS/cGMP Pathway.
Despite pharmacotherapeutic advances, cardiovascular disease (CVD) remains the primary cause of global mortality. Alternative approaches, such as herbal medicine, continue to be sought to reduce this burden. is recognized for many medicinal values, yet its vasculoprotective effects remain poorly investigated. Here, we subjected rat thoracic aortae to increasing doses of an ethanolic extract of (OME). OME induced relaxation in a dose-dependent manner in endothelium-intact rings. This relaxation was significantly blunted in denuded rings. N(ω)-nitro-l-arginine methyl ester (L-NAME) or 1H-[1,2,4]oxadiazolo[4,3,-a]quinoxalin-1-one (ODQ) significantly reduced the OME-induced vasorelaxation. Cyclic guanosine monophosphate (cGMP) levels were also increased by OME. Moreover, wortmannin or LY294002 significantly reduced OME-induced vasorelaxation. Blockers of ATP-sensitive or Ca2+-activated potassium channels such as glibenclamide or tetraethylamonium (TEA), respectively, did not significantly affect OME-induced relaxation. Similarly, verapamil, a Ca channel blocker, indomethacin, a non-selective cyclooxygenase inhibitor, and pyrilamine, a H1 histamine receptor blocker, did not significantly modulate the observed relaxation. Taken together, our results show that OME induces vasorelaxation via an endothelium-dependent mechanism involving the phosphoinositide 3-kinase (PI3-K)/ endothelial nitric oxide (NO) synthase (eNOS)/cGMP pathway. Our findings further support the medicinal value of marjoram and provide a basis for its beneficial intake. Although consuming marjoram may have an antihypertensive effect, further studies are needed to better determine its effects in different vascular beds
First report of grapevine dieback caused by Lasiodiplodia theobromae and Neoscytalidium dimidiatum in Basrah, Southern Iraq
In Basrah, grapevines suffer from dieback. Lasiodiplodia theobromae and Neoscytalidium dimidiatum were isolated from diseased grapevines, Vitis vinifera L. and identified based on morphological characteristics and DNA sequence data of the rDNA internal transcribed spacer (ITS) region. The results of the pathogenicity test conducted under greenhouse conditions for L. theobromae and N. dimidiatum reveal that both species were the causal agents of grapevines diebacks in Basrah, Southern Iraq. A brief description is provided for the isolated species.Key words: grapevine, dieback, Lasiodiplodia theobromae, Neoscytalidium dimidiatum, internal transcribed spacer (ITS), rDNA, Iraq
Assessment of the Extent of Myocardial Injury in Patients Undergoing Transvenous Implantation of a Pacemaker Using Cardiac Troponin I as a Marker of Structural Heart Damage and Its Relation to Different Sites of RV Implantation
Background and Aim: This study aimed to evaluate the degree of myocardial injury that occurs after transvenous pacemaker implantation using cardiac troponin I (cTnI) as a myocardial injury marker and the relationship between the number of screws, different sites of right ventricle (RV) lead implantation, and myocardial injury. Materials and Methods: Fifty patients at Ain Shams University Hospitals who underwent transvenous implantation of single- or dual-chamber permanent pacemakers were included in the study. According to the site of RV lead implantation, the study population was divided into 2 equal groups, 25 patients each. In the first group, the RV lead was implanted in the RV apex and in the other group, the RV lead was implanted in the RV septum. Results: In all patients, the cTnI level was elevated after pacemaker implantation, showing a significant relationship between transvenous pacemaker implantation and the incidence of myocardial injury. Comparing the RV apical pacing group with the RV septal pacing group, a greater rise in cTnI was recognized in the septal RV pacing group, indicating a significant relationship between the site of RV lead implantation and the degree of myocardial injury being more in the RV septum than in the RV apex. Moreover, the higher the number of attempts of screwing the lead in different RV sites caused more rise in cTnI, denoting a significant relationship between the number of screwing attempts and the extent of myocardial injury. Conclusion: Transvenous pacemaker implantation is associated with an increased incidence of myocardial injury, and septal RV lead implantation is associated with a higher degree of myocardial injury than apical RV lead implantation. In addition, a higher number of screwing attempts of the RV lead into the myocardium is associated with a higher degree of myocardial injury
Undiagnosed endometrial abnormalities in women with normal hysterosalpingography scheduled for IVF: prospective evaluation of three-dimensional transvaginal ultrasound versus office hysteroscopy
Objectives: To compare the diagnostic accuracy of three-dimensional transvaginal ultrasound (3D-US) to office hysteroscopy (OH) in the screening of uterine cavity with normal hysterosalpingography (HSG) findings for subtle endometrial abnormalities before in vitro-fertilization (IVF).
Methods: A prospective cohort cost-modeling study was carried out in a University hospital. We included 120 infertile women with a normal uterine cavity on HSG scheduled for IVF. All cases were evaluated by 3D-US, and the results were compared with OH findings.
Results: OH revealed cavitary endometrial lesions (CLs) in thirty-four women (28.3%). Endometrial polyps were the most common detected lesions (16, 47.1%). 3D-US had 88.2% sensitivity, 96.5% specificity, 90.9% positive predictive value, 95.4% negative predictive value, and 94.2% overall accuracy for CLs. The overall agreement between 3D-US and OH was near-perfect (κ=0.86, 95% CI=0.75-0.96). Irregular menstrual bleeds and prior endometrial procedures were significant predictors for CLs (aOR=24.96, 95% CI=2.71–230.04, P=0.005, aOR=9.16, 95% CI=2.13–39.3, P=0.002, respectively). A selective screening strategy discerning OH to women with these predictors and/or women with abnormal 2D-US would have an NPV of 92.8 % with substantial cost benefits.
Conclusions: In the pre-IVF work up, 3D-US, a non-invasive imaging modality, seems to be nearly comparable to OH. Office hysteroscopy screening prioritizing women with abnormal 2D-US, irregular menstrual periods and/or prior endometrial traumatization could yield a satisfactory cost-effective approach for identifying endometrial lesions
Longevity-Related Gene Transcriptomic Signature in Glioblastoma Multiforme
Glioblastoma multiforme (GBM) (grade IV astrocytoma) has been assumed to be the most fatal type of glioma with low survival and high recurrence rates, even after prompt surgical removal and aggressive courses of treatment. Transcriptional reprogramming to stem cell-like state could explain some of the deregulated molecular signatures in GBM disease. The present study aimed to quantify the expression profiling of longevity-related transcriptional factors SOX2, OCT3/4, and NANOG to evaluate their diagnostic and performance values in high-grade gliomas. Forty-four specimens were obtained from glioblastoma patients (10 females and 34 males). Quantitative real-time polymerase chain reaction was applied for relative gene expression quantification. In silico network analysis was executed. NANOG and OCT3/4 mRNA expression levels were significantly downregulated while that of SOX2 was upregulated in cancer compared to noncancer tissues. Receiver operating characteristic curve analysis showed high diagnostic performance of NANOG and OCT3/4 than SOX2. However, the aberrant expressions of the genes studied were not associated with the prognostic variables in the current population. In conclusion, the current study highlighted the aberrant expression of certain longevity-associated transcription factors in glioblastoma multiforme which may direct the attention towards new strategies in the treatment of such lethal disease
Evaluation of Self-Nanoemulsifying Drug Delivery Systems (SNEDDS) for Poorly Water-Soluble Talinolol: Preparation, in vitro and in vivo Assessment
ObjectiveThe aim of this study was to investigate the in vitro and in vivo performance of self-nanoemulsifying drug delivery systems (SNEDDSs) of talinolol (TAL), a poorly water-soluble drug.MethodsSelf-nanoemulsifying drug delivery systems of TAL were prepared using various oils, non-ionic surfactants and/or water-soluble co-solvents and assessed visually/by droplet size measurement. Equilibrium solubility of TAL in the anhydrous and diluted SNEDDS was conducted to achieve the maximum drug loading. The in vitro dissolution experiments and human red blood cells (RBCs) toxicity test, ex vivo gut permeation studies, and bioavailability of SNEDDS in rats were studied to compare the representative formulations with marketed product Cordanum® 50 mg and raw drug.ResultsThe results from the characterization and solubility studies showed that SNEDDS formulations were stable with lower droplet sizes and higher TAL solubility. From the dissolution studies, it was found that the developed SNEDDS provided significantly higher rate of TAL release (>97% in 2.0 h) compared to raw TAL and marketed product Cordanum®. The RBC lysis test suggested negligible toxicity of the formulation to the cells. The ex vivo permeability assessment and in vivo pharmacokinetics study of a selected SNEDDS formulation (F6) showed about four-fold increase in permeability and 1.58-fold enhanced oral bioavailability of TAL in comparison to pure drug, respectively.ConclusionTalinolol loaded SNEDDS formulations could be a potential oral pharmaceutical product with high drug-loading capacity, improved drug dissolution, increased gut permeation, reduced/no human RBC toxicity, and enhanced oral bioavailability
Ziziphus nummularia attenuates the malignant phenotype of human pancreatic cancer cells: Role of ros
Pancreatic cancer (PC) is the fourth leading cause of all cancer-related deaths. Despite major improvements in treating PC, low survival rate remains a major challenge, indicating the need for alternative approaches, including herbal medicine. Among medicinal plants is Ziziphus nummu-laria (family Rhamnaceae), which is a thorny shrub rich in bioactive molecules. Leaves of Ziziphus nummularia have been used to treat many pathological conditions, including cancer. However, their effects on human PC are still unknown. Here, we show that the treatment of human pancreatic ductal adenocarcinoma cells (Capan-2) with Ziziphus nummularia ethanolic extract (ZNE) (100–300 µg/mL) attenuated cell proliferation in a time-and concentration-dependent manner. Pretreatment with N-acetylcysteine, an ROS scavenger, attenuated the anti-proliferative effect of ZNE. In addition, ZNE significantly decreased the migratory and invasive capacity of Capan-2 with a concomitant downregulation of integrin α2 and increased cell–cell aggregation. In addition, ZNE inhibited in ovo angiogenesis as well as reduced VEGF and nitric oxide levels. Furthermore, ZNE downregulated the ERK1/2 and NF-κB signaling pathways, which are known to drive tumorigenic and metastatic events. Taken together, our results suggest that ZNE can attenuate the malignant phenotype of Capan-2 by inhibiting hallmarks of PC. Our data also provide evidence for the potential anticancer effect of Ziziphus nummularia, which may represent a new resource of novel anticancer compounds, especially ones that can be utilized for the management of PC
- …