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21.
The anticancer drug doxorubicin causes testicular toxicity as an undesirable effect. The present study was undertaken to investigate the possible protection of ellagic acid and rosmarinic acid during doxorubicin administration. For this purpose eight groups of male Sprague–Dawley rats were used (n = 10), one group received vehicle served as control, and other groups received 5 mg/kg doxorubicin twice a week for 2 weeks for a cumulative dose of 20 mg/kg, ellagic acid (10 mg/kg/day, 14 consecutive days p.o.), rosmarinic acid (75 mg/kg/day, 14 consecutive days p.o.), ellagic acid and rosmarinic acid. The latter three regimens were given to control and doxorubicin‐received rats. Doxorubicin decreased testicular relative weight, sperm count, motility, serum testosterone, testicular glycogen, and sialic acid with increased incidence of histopathological changes, oxidative stress, tumor necrosis factor‐alpha, as well as cholinesterase activity. Conversely, ellagic and rosmarinic acid treatment ameliorated such damage, thus showing the possibility to use as an adjuvant during doxorubicin treatment.  相似文献   
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  • This study investigated seed germination of Cardiospermum halicacabum, a medicinally important invasive species.
  • We compared mass, moisture content (MC), dormancy and dormancy‐breaking treatments and imbibition and germination of scarified and non‐scarified seeds of C. halicacabum from a low‐elevation dry zone (DZ), low‐elevation wet zone (WZ1) and mid‐elevation wet zone (WZ2) in Sri Lanka to test the hypothesis that the percentage of seeds with water‐impermeable seed coats (physical dormancy, PY) decreases with increased precipitation.
  • Seed mass was higher in WZ2 than in DZ and WZ1, while seed MC did not vary among the zones. All scarified DZ, WZ1 and WZ2 and non‐scarified DZ and WZ1 seeds imbibed water, but only a few non‐scarified WZ2 seeds did so. When DZ and WZ1 seeds were desiccated, MC and percentage imbibition decreased, showing that these seeds have the ability to develop PY. GA3 promoted germination of embryos excised from fresh DZ and WZ1 seeds and of scarified WZ2 seeds.
  • At maturity, seeds from DZ and WZ1 had only physiological dormancy (PD), while those from WZ2 had combinational dormancy (PY+PD). Thus, our hypothesis was not supported. Since a high percentage of excised embryos developed into normal seedlings; this is a low‐cost method to produce C. halicacabum plants for medicinal and ornamental purposes.
  相似文献   
23.
Polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) were determined in eight sampling sites collected from El-Mex Bay sediments during the period of 2013–2015. Concentrations of PCBs, Hexachlorocyclohexanes (HCHs), Dichloro Diphenyl Trichloroethanes (DDTs), and cyclodienes ranged from 0.148 to 23.99, ND to 0.089, ND to 4.64, and 0.005 to 0.581 ng g?1 dry wt, respectively. Total organic carbon (TOC) was relatively low, ranging from 0.09% to 1.42%. Total carbonate content ranged from 38% to 58%. The negative correlation of TOC with total pesticides (r = ?0.18) suggested that TOC does not have a role binding with pesticides. On the other hand, a positive correlation between PCBs and TOC (r = 0.254 at p > 0.01) was observed probably due to the low solubility of PCBs in the seawater. So, it will continue to precipitate until it reaches the bottom water and contaminates the sediment. The data obtained in the present work compared well with the counterpart data reported internationally. In general, the results of PCBs and OCP concentrations in El-Mex Bay sediments were much lower than the permissible levels recorded by sediment quality guidelines (SQGs). Interestingly, the organochlorines in sediments of El-Mex Bay were below the respective SQG values and were not likely to pose potential biological adverse impact.  相似文献   
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Mitotic chromosomal aberrations and DNA polymorphism (RAPD marker) were carried out on the Nile tilapia Oreochromis niloticus collected from five sites in Minia governorate, Egypt to test their applicability as biomonitors for heavy metal contaminants of water. The diploid chromosome number of O. niloticus population was 2 n = 44. Different types of chromosomal aberrations were recorded (e.g., deletion, ring, centromeric attenuation, end-to-end association, dicentric chromosome, stickiness chromosomes, endomitosis, fragments and chromatid gap). The chromosomal aberrations varied between O. niloticus population collected from five sites, and the most common type was ring (R) chromosomes. Samples obtained from Bahr Yousef and Irrigation drain exhibited the highest aberration frequency. The frequency of chromosomal aberration was positively correlated with the concentration of heavy metals where their concentration in the surface water of Irrigation drain and Bahr Yousef exceeded the limits defined by WHO as well as the concentration of Pb in muscles. The RAPD marker was also used to identify genetic variation among Nile tilapia samples collected from five different water sources. It created polymorphic and unique bands that can be used as genetic markers to track DNA variations. The dendrogram also revealed that exposure to heavy metal pollution causes gradual accumulation of variance, whereas areas subjected to environmental stress showed higher genetic variation and clustered together.  相似文献   
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Locally advanced breast cancer (LABC) is an aggressive disease characterized by late clinical presentation, large tumor size, treatment resistance and low survival rate. Expression of EGFR/HER2 and activation of intracellular tyrosine kinase domains in LABC are associated with poor prognosis. Thus, target therapies such as the anti-receptor tyrosine kinases lapatinib drug have been more developed in the past decade. The response to lapatinib involves the inhibition of RTKs and subsequently signaling molecules such as Src/STAT3/Erk1/2 known also to be activated by the cytokines in the tumor microenvironment (TME). The aim of the present study is to identify the major cytokine that might contribute to lapatinib resistance in EGFR+/HER2+ LABC patients. Indeed, tumor associated macrophages (TAMs) are the main source of cytokines in the TME. Herein, we isolated TAMs from LABC during modified radical mastectomy (MRM). Cytokine profile of TAMs revealed that IL-8 is the most prominent highly secreted cytokine by TAMs of LABC patients. Using in-vitro cell culture model we showed that recombinant IL-8 (50 and 100 ng/mL) at different time intervals interfere with lapatinib action via activation of Src/EGFR and signaling molecules known to be inhibited during treatment. We proposed that to improve LABC patients' response to lapatinib treatment it is preferred to use combined therapy that neutralize or block the action of IL-8.  相似文献   
29.
A series of new 9-glycosyl-4,9-dihydropyrano[3,4-b]indole-1(3H)-ones 3 was synthesized in moderate to low yields. 4,9-Dihydropyrano[3,4-b]indole-1(3H)-ones (1) were coupled with different acetobromoglycopyranoses 2 in refluxing toluene in the presence of silver oxide to afford one coupling product of the respective N-glycosides. α-L-Arabinopyranosides 3j and 3m were the most active glycosides among the tested compounds against certain Gram positive and Gram negative bacterial strains.  相似文献   
30.
Soil contamination with petroleum hydrocarbon products such as diesel and engine oil is becoming one of the major environmental problems. This study describes hydrocarbons degrading bacteria (PHAD) isolated from long-standing petrol polluted soil from the eastern region, Dammam, Saudi Arabia. The isolated strains were firstly categorized by accessible shape detection, physiological and biochemistry tests. Thereafter, a technique established on the sequence analysis of a 16S rDNA gene was used. Isolation of DNA from the bacterial strains was performed, on which the PCR reaction was carried out. Strains were identified based on 16S rDNA sequence analysis, As follows amplified samples were spontaneously sequenced automatically and the attained results were matched to open databases. Among the isolated bacterial strains, S1 was identified as Staphylococcus aureus and strain S1 as Corynebacterium amycolatum.  相似文献   
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