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Biomedical subjects

M A Moustafa

Publications and source records attributed to M A Moustafa.

At least 19 recordsLinked to original sources
PubMed2002

Accumulation of lead and cadmium in the marine prosobranch Nerita saxtilis, chemical analysis, light and electron microscopy.

The potential value of the marine prosobranch Nerita saxtilis as an efficient biological monitor to heavy metal pollution in the Red Sea was investigated. Storage ability of lead and cadmium was compared in shell, headfoot and digestive gland of the marine snail N. saxtilis collected from Al-Hamrauin area at El-kuseir (lead, 300.35 +/- 28.53 microg/l, 1,716 +/- 16.14. cadmium 20.01 +/- 1.8 microg/l, 161.72 +/- 21.4 mean +/- S.D. for water and sediment, respectively) relative to that of inhabiting marine water and sediment employing atomic absorption spectrometry to determine the organ with highest capability of heavy metal accumulation. The influence of metal storage on light microscopic structure of that organ was investigated. Also, the ultrastructure localization of storage sites in the same organ was determined employing transmission electron microscopy. The digestive gland was shown to accumulate both metals at conccntrations that are several orders of magnitude higher than those in the surrounding marine water. The bioaccumulation capability of lead and cadmium was ranked in the following order; digestive gland > headfoot > shell for lead and digestive gland > shell > headfoot for cadmium. In spite of its evident highest metal storage capability, no histopathological changes were observed in the digestive gland of that marine prosobranch. Enlarged electron dense vesicles and many granules were observed in ultrathin sections in digestive cells of these snails and are suggested to be the sites of storage of detoxified metals. The results of that finding indicate the possibility of using the marine prosobranch N. saxtilis as biomonitor for heavy metal contaminants in the Red Sea.

Animals↗
PubMed2001

The effect of melatonin on eye lens of rats exposed to ultraviolet radiation.

We investigated the influence of exogenously administered melatonin on adult rats eye lenses exposed to ultraviolet radiation (UV) A and B ranging from 356-254 nm irradiation at 8 microW/cm(2). Rats exposed to this range of UV for 15 min for one week showed a significant (P<0.05) reduction in antioxidant enzymes activities; superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and elevated (P<0.001) lipid peroxidation served as an index of cellular damage by free radicals. UV-radiation significantly (P<0.001) elevated calcium ions (Ca(2+)) and lactate dehydrogenase (LDH) activity in lenses. Depleting animals of their stores of important intracellular antioxidant and elevating lenticular Ca(2+) by UV irradiation, may be the main cause of lens opacification. Melatonin injection with radiation significantly reduced (P<0.05) lipid peroxidation, Ca(2+) and (P<0.001) for LDH. When melatonin was injected after radiation, SOD and GSH-Px enzyme activities increased significantly (P<0.01), and lipid peroxidation, Ca(2+) levels and LDH activities were reduced significantly. Melatonin injection after UV radiation was as effective as melatonin treatment concurrent with UV irradiation. We conclude that melatonin may protect the eye lens from the damaging effects of UV exposure, and its actions protect lens from oxidative stress, elevating Ca(2+) levels, which are considered as an important causes of cataractogenesis.

Animals↗
PubMed2000

Modulation of the pathologic and apoptotic changes of experimental toxoplasmosis by concomitant infection with Trichinella spiralis.

This study shows that Toxoplasma gondii infection is capable of inducing a process of programmed cell death not only in the infected hepatocytes of experimental murine model, but also the neighbouring non-infected cells. However, some cells showed a possible mixed apoptotic and necrotic pattern. Surprisingly, lymphocytes and Kupffer cells in portal sinusoids nearby the parasite vacuoles showed no apparent changes. Toxoplasma in concomitant infection with a different parasite, Trichinella spiralis, clearly mitigate the pathologic and apoptotic changes caused by T. gondii. These findings might help in understanding the problematic biology and immunopathogenesis of T. gondii. The results also augments previous reports by the same authors about the possible protective role of heterologous antigens of one parasite against a biologically and immunologically different parasite.

Animals↗
PubMed1999

Reciprocal heterologous protection between Trichinella spiralis and Toxoplasma gondii concurrently present in experimental murine models.

Mixed parasitic infections have been long seen as a double impact on the host. In this study a different view of polyparasitism is demonstrated. The influence of the immunological environments created by two biologically different parasites on the pathogenesis of each other was evaluated. Swiss albino mice were sequentially infected with the intracellular protozoan Toxoplasma gondii (acute and latent), which elicits a T-helper 1 (Th1)-polarized immune response and the helminth parasite Trichinella spiralis, whose infection is predominated by a Th2 response. The results show a significant heterologous protection from one parasite towards the other. There was a highly significant lower Trichinella muscle larvae burden in mixed infection group compared to single Trichinella infection, in spite of delayed intestinal adult worm expulsion in the mixed infection group. A highly significant lower burden of T. gondii brain cysts in mixed infection compared to single latent Toxoplasma infection was also demonstrated. Concerning the anti-Toxoplasma antibody response, there was a significant lower levels in the latent Toxo-Trich. group compared to the group of latent toxoplasmosis only. These significant lower antibody titers were reproducible by two different assays; dye test and direct agglutination test.

Animals↗
PubMed1998

Toxocariasis as a possible cause of allergic diseases in children.

Allergic diseases are common in young children yet the cause of allergy remains unknown in most of them. The association of Toxocara infection with two common allergic diseases in children was investigated. Sera from 60 children (average age 4-6y) suffering from idiopathic bronchial asthma or chronic urticaria were tested for toxocariasis using ELISA test and compared to 30 apparently healthy age matched children . Seropositive children were investigated for evidence of sensitization by measuring serum specific IgE concentration and eosinophil count. The frequency of Toxocara seropositivity was 26.6%, 13.3% and 30% in asthmatic, chronic urticarial and control children respectively. The seropositive allergic children showed significant increase in IgE and eosinophil levels when compared to controls. A contribution of toxocariasis to the allergic sensitization was suggested.

Animals↗
PubMed1997

The potential risk of contracting toxocariasis in Heliopolis district, Cairo, Egypt.

Out of 600 soil samples collected from 3 sport clubs and 3 public parks within Heliopolis district, 182 samples contained Toxocara species eggs with an overall prevalence rate of 30.3%. Public parks especially children's sand boxes had the highest percentage of the recovered eggs. Prevalence did not vary greatly from winter to summer though more viable eggs were noticed in the samples collected in winter. The findings demonstrate the potential risk of contracting toxocariasis (VLM) by children playing in the sand boxes of the investigated areas.

Animals↗
PubMed1997

An evaluation of the modified agar plate method for diagnosis of Strongyloides stercoralis.

An examination of 320 random stool samples from patients aged 7-60 years in Kafr-Sakr Hospital, was done to compare the efficacy of modified agar plate method to traditional method for diagnosis of Strongyloides stercoralis infection. Out of 320 cases examined 27 were positive for strongyloidiasis by all means. The traditional methods detected 37% and 48.1% from the positive cases by single and repeated 3 days examination respectively. The modified agar plate detected 70.3% and 96.2% among positive cases by single and 3 days examination respectively. The modified agar plate was twice efficient than the traditional methods. Precautions taken to obtain the best result were discussed. Considering the other advantages of this technique, it was concluded that it may eventually become the test of choice in diagnosis of strongyloidiasis.

Adolescent↗
PubMed1996

Experimental congenital toxocariasis: effect on foetal future immune response.

Congenital parasitic infections may not lead to any overt clinical effects but could modulate the foetal future immune response to the same parasite depending on whether sensitization or tolerance has occurred in utero. In this study, pregnant female mice were infected with Toxocara canis eggs at different gestational age, then the offspring were next challenged with Toxocara eggs 6 weeks after birth and their immune response was assessed by estimation of the eosinophilic count and serum IgE concentration. The Total larval count (TLC), brain parasitism (BP) and reduction % in (TLC) were used as criteria for the course of infection. It was found that exposure to infection during pregnancy whether early or late led not only to transmission of larvae to the foetus but also to modulation of its immune response and course of infection when next encountered the parasite after birth. The offspring when compared to control from non-infected mothers were hyporesponsive when infection occurred early during pregnancy and they showed high immune responsiveness when infection was induced late in pregnancy. The potential clinical application of these findings was suggested. It is now an established fact that immunocompetence in the mammalian foetus including humans develops very early in utero. Therefore, the foetus is capable of showing some forms of activity against invasion by maternal pathogenic organisms or their antigens (Loke, 1978). Moreover, the early contact with parasitic antigens may affect the foetus future immune response when it next encounters similar organisms after birth. Palmer (1978) reported a rapid secondary immune response in the offspring of Plasmodium berghei infected female rats when challenged with the parasite and compared to control groups from non-infected mothers. An apposite response was reported by Hang et al. (1974) who noticed that massive infection of pregnant mice with Schistosoma mansoni cercariae resulted in offspring hyporesponsive to subsequent challenge assessed by the diameter of the egg granulomas. Considering that toxocariasis is a frequent and potentially serious disease affecting primarily young children, also congenital toxocariasis was well documented since the original studies of Fulleborn (1921), this study was designed to reveal the extent to which the foetus future immune response can be modulated by maternal toxocariasis in experimental animals. The estimation of the immune response included IgE level (antibody mediated mechanism) and the absolute eosinophils count (a manifestation of cell mediated immune response) since eosinophil/IgE/mast cell axis represents a specialized immune mechanism that may contribute directly to parasite damage in toxocariasis (Knight, 1982). Also, (TLC), (B.P) and reduction % in (TLC) were used as criteria for the course of infection.

Animals↗
PubMed1996

Synthesis and antiinflammatory activity of certain thienopyrimidine derivatives.

Interaction of ethyl 2-amino-4,5,6, 7-tetrahydrobenzo[b]thiophene-3-carboxylate 1 with 2-thiophene carbonyl chloride 2 afforded ethyl 2-(2-thenoylamino)-4, 5,6,7-tetrahydrobenzo[b]thiophene-3-carboxylate 3 which upon cyclization yielded 2-(2-thienyl)-5,6,7, 8-tetrahydrobenzo[b]-thieno[2,3-d]-4H-3, 1-oxazin-4-one 4 and 2(2-thienyl)-3-amino-5, 6,7,8-tetrahydrobenzo-[b]thieno[2,3-d]-3,4-dihydropyrimidin-4-one 6. Some of the prepared compounds were screened for their antiinflammatory activity, compound 7c and 9b showed significant activity.

Animals↗
PubMed1995

Genome size and chromosomes in marine sponges [Suberites Domuncula, Geodia Cydonium].

The genome size of the marine sponges Suberites domuncula and Geodia cydonium has been determined by flow cytofluorometric analysis using diamidino-phenylindole [DAPI]. Using human lymphocytes as reference the amount of DNA in cells from S. domuncula has been determined to be 3.7 pg and that of G. cydonium 3.3 pg. While no chromosomes could be identified in G. cydonium, the karyotype of the Suberites domuncula is 32 chromosomes in the diploid state. The size of the chromosomes was between 0.25 and 1.0 micron. No pronounced banding pattern was visible.

Animals↗
PubMed1992

Synthesis and antimicrobial activity of 3-(substituted-phenyl)-sydnones.

3-(3 or 4-Acetylphenyl)-sydnones 7, 8 have been synthesized by formation of the glycines 3, 4, followed by nitrosation to 5, 6 and cyclization with acetic anhydride to sydnones. Sydnone derivatives carrying chalcone moieties 15, 16 were prepared by formation of the chalcone analogues 11, 12 through condensation of the glycines 3, 4 with the appropriate aldehydes, followed by the reactions applied for the preparation of 7, 8. The sydnone derivatives were screened for antimicrobial activities.

Anti-Bacterial Agents↗
PubMed1991

Percentages of the deuterium retained after para-hydroxylation of (R)(+)4-2H-phenytoin and (S)(-) 4-2H-phenytoin in rat.

(R)(+) and (S)(-) 4-2H-phenytoin have been used as substrates for the determination of the percentage of deuterium retention (NIH shift) after para-hydroxylation of the substrates in rat. By using GC-MS analyses, the percentages of deuterium retention were found to be 69% and 70% for the (R) and (S) phenyl rings, respectively. The results add additional evidence for the involvement of arene oxide in the oxidation of the pro (R) and pro (S) phenyls of phenytoin. The oxidation process of each ring could be mediated by independent enzyme systems, a rapid oxidative enzyme for the pro (S) phenyl and a slow oxidative enzyme for the pro (R) phenyl.

Animals↗
PubMed1990

Comparative study on the para-metabolic oxidation of phenytoin and decadeuteriophenytoin.

The in-vivo metabolic conversion of equal mixture of phenytoin and decadeuteriophenytoin to the para-hydroxy metabolite in rat was investigated in order to verify a possible role of an insertion or abstraction mechanisms in the hydroxylation process. Determination of kH/k2H values of urine samples at 2 h intervals for 24 h indicated that there was no isotope effect during in-vivo para-hydroxylation of phenytoin. This gives evidence of the arene oxide intermediacy possibly being the sole pathway for para-hydroxylation of phenytoin.

Animals↗
PubMed1987

Caudal cruciate ligament function and injury in the horse.

The caudal cruciate ligament assists the medial femorotibial ligament in supporting the medial aspect of the femorotibial joint. It also limits the outward rotation of the tibia during weight bearing. In two lame horses tearing of the caudal portion of the femoral attachment of the caudal cruciate ligament was recorded together with cracking and tearing of the medial meniscus. In one case, synovitis and restrictive fibrous periarthritis were the sequelae of secondary stifle sepsis.

Animals↗
PubMed1981

Phenobarbital solubility in propylene glycol-glycerol-water systems.

Phenobarbital solubility in various binary and ternary propylene glycol-glycerol-water solvent systems was determined. Phenobarbital concentrations several times those of the ethanol-containing USP and BPC elixirs were obtained. From log solubility-solvent composition plots, a general equation was developed for phenobarbital solubility prediction in propylene glycol-water, glycerol-water, and propylene glycol-glycerol-water solvent systems. Solubility predictions using another equation, based on linear log solubility-dielectric constant relationships, were limited by the need to use different constants for different solvent blends. Heats of solution for phenobarbital determined in selected solvent blends as well as in USP and BPC elixirs varied within a very narrow range, suggesting similar solute-solvent interactions.

Glycerol↗