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21.
Peroxidase-mediated toxicity to schistosomula of Schistosoma mansoni 总被引:16,自引:0,他引:16
E C Jong A A Mahmoud S J Klebanoff 《Journal of immunology (Baltimore, Md. : 1950)》1981,126(2):468-471
Guinea pig eosinophil peroxidase (EPO) was capable of killing schistosomula of Schistosoma mansoni in vitro when combined with hydrogen peroxide and a halide. Killing was measured by 51Cr release, by microscopic evaluation of viability, and by reinfection experiments in mice. Parasite killing was dependent on each component of the EPO-H2O2-halide system, was completely inhibited by catalase and azide, and was partially inhibited by cyanide. The EPO-mediated system required 10(-4) M H2O2 and 10(-4) M iodide at pH 7.0, and the schistosomula were killed with exposure to this system of less than 30 min at 37 degrees C. At pH 6.0, the EPO-mediated system showed significant cidal activity with 10(-6) M iodide. Canine neutrophil peroxidase (myeloperoxidase [MPO]) was also able to kill schistosomula in vitro in the presence of 10(-4) M H2O2 and 10(-4) iodide at pH 7.0 and pH 6.0. Physiologic concentrations of chloride (0.1 M) could substitute for iodide at pH 7.0 and pH 6.0 as the halide cofactor; however, at pH 7.0, a higher concentration of enzyme was required. These findings with isolated enzyme systems are compatible with a role for peroxidase in the host defense against schistosomula. 相似文献
22.
W Palm JL Sampaio M Brankatschk M Carvalho A Mahmoud A Shevchenko S Eaton 《PLoS genetics》2012,8(7):e1002828
Interorgan lipid transport occurs via lipoproteins, and altered lipoprotein levels correlate with metabolic disease. However, precisely how lipoproteins affect tissue lipid composition has not been comprehensively analyzed. Here, we identify the major lipoproteins of Drosophila melanogaster and use genetics and mass spectrometry to study their assembly, interorgan trafficking, and influence on tissue lipids. The apoB-family lipoprotein Lipophorin (Lpp) is the major hemolymph lipid carrier. It is produced as a phospholipid-rich particle by the fat body, and its secretion requires Microsomal Triglyceride Transfer Protein (MTP). Lpp acquires sterols and most diacylglycerol (DAG) at the gut via Lipid Transfer Particle (LTP), another fat body-derived apoB-family lipoprotein. The gut, like the fat body, is a lipogenic organ, incorporating both de novo-synthesized and dietary fatty acids into DAG for export. We identify distinct requirements for LTP and Lpp-dependent lipid mobilization in contributing to the neutral and polar lipid composition of the brain and wing imaginal disc. These studies define major routes of interorgan lipid transport in Drosophila and uncover surprising tissue-specific differences in lipoprotein lipid utilization. 相似文献
23.
Dilutable nanoemulsions are potent drug delivery vehicles for ophthalmic use due to their numerous advantages as sustained
effect and high ability of drug penetration into the deeper layers of the ocular structure and the aqueous humor. The aim
of this article was to formulate the antiglaucoma drug dorzolamide hydrochloride as ocular nanoemulsion of high therapeutic
efficacy and prolonged effect. Thirty-six systems consisting of different oils, surfactants, and cosurfactants were prepared
and their pseudoternary-phase diagrams were constructed by water titration method. Seventeen dorzolamide hydrochloride nanoemulsions
were prepared and evaluated for their physicochemical and drug release properties. These nanoemulsions showed acceptable physicochemical
properties and exhibited slow drug release. Draize rabbit eye irritation test and histological examination were carried out
for those preparations exhibiting superior properties and revealed that they were nonirritant. Biological evaluation of dorzolamide
hydrochloride nanoemulsions on normotensive albino rabbits indicated that these products had higher therapeutic efficacy,
faster onset of action, and prolonged effect relative to either drug solution or the market product. Formulation of dorzolamide
hydrochloride in a nanoemulsion form offers, thus, a more intensive treatment of glaucoma, a decrease in the number of applications
per day, and a better patient compliance compared to conventional eye drops. 相似文献
24.
Xingxing Yuan Yurong Tan Ousman Bajinka Modou L. Jammeh Abubakarr Dukureh Chidera N. Obiegbusi Khalid A. Abdelhalim Mahmoud Mohanad 《Cell biochemistry and function》2024,42(2):e3941
Both the epigenetic changes and gut microbiota (GM) have attracted a growing interest in establishing effective diagnostics and potential therapeutic strategies for a number of diseases. These disorders include metabolic, central nervous system-related diseases, autoimmune, and gastrointestinal infections (GI). Despite the number of studies, there is no extensive review that connects the epigenetics modifications and GM as biomarkers that could confer effective diagnostics and confer treatment options. To this end, this review hopes to give detailed information on connecting the modifications in epigenetic and GM. An updated and detailed information on the connection between the epigenetics factors and GM that influence diseases are given. In addition, the review showed some associations between the epigenetics to the maternal GM and offspring health. Finally, the limitations of the concept and prospects into this new emerging discipline were also looked into. Although this review elucidated on the maternal diet and response to offspring health with respect to GM and epigenetic modifications, there still exist various limitations to this newly emerging discipline. In addition to integrating complementary multi-omics data, longitudinal sampling will aid with the identification of functional mechanisms that may serve as therapeutic targets. To this end, this review gave a detailed perspective into harnessing disease diagnostics, prevention and treatment options through epigenetics and GM. 相似文献
25.
Ahmed A. Morsi Lamiaa M. Shawky Tamer M. Shawky Mohamed H. Bahr Mahmoud Tawfiq Abu Alnasr Eman El Bana 《Cell biochemistry and function》2024,42(1):e3927
Gastric ulceration is a prevalent worldwide clinical presentation due to altered gastric defense mechanisms. Nonsteroidal anti-inflammatory drugs are one of the common causes of gastric ulcers mediated by the release of inflammatory mediators. The study aimed to investigate the potential protective effect of soyasaponin I (soya) against diclofenac (DIC)-induced gastric ulcer in rats and to highlight the underlying mechanisms. The experiment was conducted on 40 male Wistar albino rats, equally distributed into five groups: control, DIC-induced ulcer (9 mg/kg/d, orally, twice daily for 3 days), ulcer/soya-, ulcer/ranitidine-, and ulcer/soya/selective nuclear factor kappa B inhibitor (JSH-23)-treated groups. The doses of soya, ranitidine, and JSH were 20, 25, and 5 mg/kg/d, respectively, given orally. Gastric specimens were prepared for gene and histological study and for biochemical analysis of gastric prostaglandin E2 (PGE2), oxidative markers, and inflammatory cytokines. The gastric samples were formalin-fixed, paraffin-embedded, and subjected to hematoxylin and eosin (H&E), PAS staining, and immunohistochemical assay for identification of nuclear factor kappa B (NF-κB), cyclooxygenase-2 (COX-2), and proliferation marker (Ki67) expressions. The findings revealed decreased gastric PGE2 and altered inflammatory and oxidative markers in the ulcer model group. The H&E staining showed mucosal injury characterized by mucosal surface defects and inflammatory cell infiltrations. The polymerase chain reaction (PCR) and immunohistochemistry demonstrated an upregulation of NF-κB and COX-2 expression at gene/protein levels; meanwhile, Ki67 downregulation. The soya-treated group showed maintained biochemical, histological, and PCR findings comparable to the ranitidine-treated group. The JSH-23-treated group still showed partial gastric protection with biochemical and immunohistochemical changes. Soyasaponin I ameliorated DIC-induced gastric ulcers by targeting the COX-2 activity through modulation of NF-κB signaling. 相似文献
26.
Noor Khalidah Abdul Hamid Peace Onas Somdare Khadijah Abdullah Md Harashid Nurul Ain Othman Zulhisyam Abdul Kari Lee Seong Wei Mahmoud A.O. Dawood 《Saudi Journal of Biological Sciences》2022,29(5):3911
The purpose of this experiment was to examine the potential use of Carica papaya leaf extract as a supplement to promote growth and improve feed utilization in red hybrid tilapia. Five diets were formulated containing isolipidic (80 g/kg) and isonitrogenic (350 g/kg) levels. All feeds contained similar types and amounts of raw materials but differed in the inclusion of papaya leaf extract (0, 5, 10, 20 and 40 g/kg feed). The initial size of fish used was 2.3 ± 0.01 g. Each diet was performed in triplicate tanks, and the feeding period was 12 weeks. Fish fed diet containing 2% papaya leaf extract (PLE) had the highest final weight, 31.14 ± 1.47 g, followed by 1% PLE (27.27 ± 1.75 g). These two diets (1% and 2%) were also showed significant improvements of weight gain, SGR, and feed efficiency of the red hybrid tilapia (p < 0.05). However, papaya leaf extract did not affect the HSI, VSI, PER, digestive enzymes activity, blood composition, and survival rate. Supplementing the diets with papaya leaf extract lowered serum urea. Findings of this research suggest that adding papaya leaf extract to the diet of red hybrid tilapia improves growth and feed efficiency without adversely affecting blood parameters. Therefore, an inclusion level between 1% and 2% of the papaya leaf extract is recommended as a feed additive to promote red hybrid tilapia fry growth. 相似文献
27.
28.
Summary The response of bacterial population to edaphic drought of the Egyptian desert in summer has been investigated. The sporeformers Bacillus subtilis, Bacillus licheniformis, and Bacillus megaterium have predominated in the soil. B. subtilis and B. licheniformis predominated in the rhizosphere of the studied chamaephytes. The total bacterial counts were found to be much higher in the rhizospheres than in the soils apart. Azotobacter sp. and Clostridium sp. have been isolated from rhizospheres but not from soils. The significance of the rhizosphere as constituting a microhabitat in the desert community, has been discussed. The probable contribution of the peritrophic mantle of bacteria for protecting root cells against edaphic drought has also been notified. 相似文献
29.
Toghyani M Toghyani M Shivazad M Gheisari A Bahadoran R 《Biological trace element research》2012,146(2):171-180
This study was conducted to determine the effects of dietary supplementation with Cr nicotinate and Cr chloride and their
optimum inclusion rate on performance, carcass traits, meat oxidative stability, serum metabolites, hematological parameters,
and liver chromium concentration in heat-stressed broilers. A total number of 420, 1-day-old male broiler chicks were randomly
assigned to seven treatments with four replicates of 15 chicks. The dietary treatments consisted of the basal diet supplemented
with 0 (control), 500, 1,000, and 1,500 μg/kg Cr in the form of Cr nicotinate and Cr chloride. Chicks were raised for 6 weeks
in heat stress condition (33 ± 2°C). Supplements of organic and inorganic Cr particularly at 1,500 μg/kg incorporation increased
feed consumption (P < 0.05) and body mass gain of broilers (P < 0.01). Cr supplementation increased carcass yield and decreased abdominal fat (P < 0.01). Supplementation of 1,500 μg/kg Cr nicotinate (P < 0.05) enhanced liver Cr concentration. Storage time increased lipid oxidation of meat (P < 0.01). Cr decreased lipid oxidation of breast and thigh muscles over 2 (P < 0.01) or 6 (P < 0.05) days of storage time. Birds fed 1,500 μg/kg Cr nicotinate, had lower concentration of serum glucose and triglyceride
at 21 days (P < 0.05). Hematological parameters tested at 21 and 42 days, were not influenced. The results suggested that dietary Cr supplementation
regardless of its source have a positive effect on productive, and carcass traits, also enhances oxidative stability of refrigerated
meat in broilers reared under heat stress conditions. 相似文献
30.