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Biomedical subjects

A A Ibrahim

Publications and source records attributed to A A Ibrahim.

At least 19 recordsLinked to original sources
PubMed2001

Effect of temperature increase from 55 to 65 degrees C on performance and microbial population dynamics of an anaerobic reactor treating cattle manure.

The effect of a temperature increase from 55 to 65 degrees C on process performance and microbial population dynamics were investigated in thermophilic, lab-scale, continuously stirred tank reactors. The reactors had a working volume of 31 and were fed with cattle manure at an organic loading rate of 3 g VS/l reactor volume/d. The hydraulic retention time in the reactors was 15 days. A stable reactor performance was obtained for periods of three retention times both at 55 degrees C and 65 degrees C. At 65 degrees C methane yield stabilized at approximately 165ml/g VS/d compared to 200 ml/g VS/d at 55 degrees C. Simultaneously, the level of total volatile fatty acids, VFA, increased from being below 0.3 g/l to 1.8-2.4 g acetate/l. The specific methanogenic activities (SMA) of biomass from the reactors were measured with acetate, propionate, butyrate, hydrogen, formate and glucose. At 65 degrees C. a decreased activity was found for glucose-, acetate-, butyrate- and formate-utilizers and no significant activity was measured with propionate. Only the hydrogen-consuming methanogens showed an enhanced activity at 65 degrees C. Numbers of cultivable methanogens, estimated by the most probable number (MPN) method, were significantly lower on glucose, acetate and butyrate at the increased operational temperature, while the numbers of hydrogenotrophic methanogens remained unchanged. No viable propionate-degrading bacteria were enriched at 65 C. Use of ribosomal oligonucleotide probes showed that an increase in temperature resulted in a decreased contribution of the rRNA of the domain bacteria from 74-79 to 57-62% of the universal probe, while the rRNA of the domain archaea, increased from 18-23 to 34-36%.

Anaerobiosis↗
PubMed1997

Bond strengths of maxillary anterior base metal resin-bonded retainers with different thicknesses.

PURPOSE: This study evaluated the effect of three different thicknesses of base metal resin-bonded retainers on retention/resistance. MATERIAL AND METHODS: Three ivorine teeth, a central incisor, lateral incisor, and canine, were prepared to receive resin bonded retainers. Fifteen metal replicas of prepared teeth were made (five for each tooth morphotype). A total of 45 metal retainers were cast in three different thicknesses, 0.3, 0.5, and 0.7 mm, with 15 for each thickness. Retainers were cemented to metal die replicas with Panavia EX luting agent. After 24 hours, forces to dislodge the retainers were applied at 45 degrees to the vertical mesiodistal plane at the proximolingual line angle. RESULTS: An increase in thicknesses resulted in elevation of dislodging forces that were almost linear for the three thicknesses of canine retainers. The central incisor exhibited the greatest increase in resistance to dislodgment between retainers that were 0.3 and 0.5 mm thick, whereas increased thickness for the lateral incisor retainer resulted in minimal or no benefit.

Analysis of Variance↗
PubMed1994

Immunoglobulins in patients with atopic dermatitis due to mites infestation in Qualyobia Governorate, Egypt.

Atopic dermatitis (A.D.) is a hereditary and distinct form of eczema which may be associated with other atopic manifestations. The aetiopothogenesis of A.D. is unknown and it is widely accepted that both intrinsic and extrinsic factors are involved. House dust mites (HDM) are of great medical importance in causing allergic manifestations in human being. In the present work, a total of 30 A.D. patients with different ages of both sexes were examined for the immunoglobulins level as compared to control group. The IgG, IgM, IgA & IgE were higher in the patients than in the controls. These differences were highly significant in the IgE. On the other hand, IgA showed no significant increase.

Adolescent↗
PubMed1994

Isolation of three species of mites from house dust of atopic dermatitis patients in Qualyobia Governorate, Egypt.

Dermatitis or inflammation of the skin caused by an outside agent, is a condition with many causes. It may result from direct irritation of the skin by a substances (chemical or insecticide) or it may be an allergic reaction to a particular substance that has been in contact with the skin as soap or detergent or insect urticating hairs; injected as insect saliva or faeces or sting or taken by mouth as food or drug. In general, treatment of dermatitis depends mainly upon the cause. In the present study, three species of mites were isolated from the dust collected from houses of atopic dermatitis patients. These mites were Dermatophagoides pteronyssinus, Ornithonyssus bacoti and Haemogamasus pontiger. The former species was the predominant one which is known to produce the most potent allergen. It was concluded that house dust mites are one of the aetiological factors of atopic dermatitis and that genera of mites other than Dermatophagoides may be considered as allergen in house dust mites.

Animals↗
PubMed1987

In vivo adherence and colonization of Vibrio cholerae strains that differ in hemagglutinating activity and motility.

A scanning electron microscopic study was carried out to compare the in vivo pathogenicity of two strains of Vibrio cholerae in an adult rabbit ligated-gut test model. V. cholerae C5 (serotype Ogawa, biotype El Tor), a motile strain possessing hemagglutinating activity in vitro, and C21 (serotype Ogawa, classical biotype), a nonmotile strain possessing no hemagglutinating activity, were tested. Tissue samples from small intestinal loops were examined 3, 6, 9, and 12 h postinoculation. Contradictory to most published data, neither hemagglutinating activity nor motility appeared to be essential prerequisites for the pathogenesis of cholera in the experimental animal model used: nonmotile hemagglutinin-negative strain C21 adhered to and colonized the small intestine at least to the same extent as did motile hemagglutinin-positive strain C5. Maximum colonization was seen at 9 h postinoculation for both strains. C5 and C21 vibrios caused comparable damage to the villi of the small intestine. The villous epithelium showed only mild changes during the first 9 h postinoculation. However, after 12 h the epithelium was seriously damaged concomitant with a decrease in the number of vibrios. Many villi showed partial or total denudation, owing to repelled epithelium, leaving a bare basal lamina with only some to moderate numbers of vibrios attached. Since similar changes were induced by pure cholera enterotoxin, these changes were likely the result of excessive fluid accumulation. From this study it is concluded that, at least in the animal model used, factors other than hemagglutinating activity and motility may also play a role in the association of V. cholerae with the small intestinal surface.

Animals↗
PubMed1986

Studies on microorganisms secured from different organs of slaughtered sheep with special reference to the microbial load in certain muscles.

A total of 312 samples collected from different organs and muscles of dead, disabled, diseased, dying, and normal carcasses of sheep were examined bacteriologically to determine the different species of microorganisms as to their public health significance. In addition, the aerobic plate count (APC) and most probable number (MPN) coliform/g were determined of Musculus biceps brachii, Musculus quadriceps femoris, and Musculus longissimus dorsi. The mean bacterial load was higher in summer than in winter in dead and in normal sheep. Moreover, the APC was higher in winter 3 hours after slaughtering than after 24 h cooling. The bacterial load decreased in that order in the muscles of dead, disabled, diseased, and dying sheep carcasses. The lowest bacterial load was recorded in the Musculus longissimus dorsi. The most predominant isolates recovered from different organs and muscles were Escherichia coli (60), staphylococci (33), Proteus vulgaris (12), Enterobacter aerogenes (11), Corynebacterium ovis (9), Alcaligenes faecalis (7), Actinomyces israelii (5), Citrobacter freundii (4), pneumococci (3), and enterococci (2). The importance is discussed of the isolated strains as zoonotic agents and for assessing the hygienic meat quality.

Animals↗
PubMed1982

Occurrence of bacterial pollution indicators in Boulti (Tilapia nilotica Linn.) fish.

A study was made for the occurrence of coliform and streptococcal groups on the skin surface (32 samples), gills (32 samples), intestinal tract (4 samples) and raw fish flesh (4 samples) and raw fish flesh (4 samples) of Boulti fish (Tilapia nilotica Linn.), a fresh water fish caught from Nasser's Lake in Aswan. Streptococcus group was detected in 13 samples taken from fish surface, 12 samples out of 32 swabs from gills. All intestine samples and raw fish flesh were positive for the streptococcus group. Coliform organisms were detected at nearly 43% of skin or gill samples, 100% of intestine and raw fish flesh samples.

Animals↗
PubMed1980

Boulti (Tilapia nilotica Linn.) fish paste. 1. Preparation and chemical composition.

Boulti fish (Tilapia nilotica Linn.) from Naser's lake in Aswan was converted to a ready marketable product (paste) in aluminium tubes. The quality of the product was ascertained by chemical indices. The product has a good flavour and can be kept for 5 weeks without undesirable changes. It is concluded that the production of fish paste in aluminium tubes is one of the possibilities of converting fish to precooked product.

Animals↗
PubMed1979

Local male hormonal therapy in male infertility: a preliminary report.

The therapeutic effect of local infiltration of the testis by testosterone crystalline suspension was studied in 18 cases of severe oligozoospermia. Evaluation was done by semen analysis follow-up, and results were correlated with preoperative testicular biopsies. About 40% of the cases showed improvement of sperm count and/or motility. Testicular biopsies of responding cases showed mild inhibitory changes, such as sloughing or partial spermatogenic arrest at late stages, while cases with tubular hyalinization or spermatogenic arrest at the stage of spermatogonia showed no response. The method proved to be simple, safe, and promising.

Adult↗
PubMed1978

Comparative evaluation of laparoscopy and hysterosalpingography in infertile patients.

A comparative study of hysterosalpingography (HSG) and laparoscopy in the investigation of infertility is presented. From 1973-1977, 352 cases were investigated with both HSG and laparoscopy. In 57.67% of the cases there was complete agreement between HSG and laparoscopy. The study included 168 cases of unexplained infertility and 184 cases with abnormal hysterosalpingographic findings. Pelvic adhesions were demonstrated in 151 cases by laparoscopy as compared to 76 cases in which its presence was only suspected by HSG. Laparoscopy revealed a 57.14% of associated pelvic pathology in cases of unexplained fertility. The present study concludes that laparoscopy as compared to HSG is not only more informative, but also more accurate and conclusive.

Adnexal Diseases↗
PubMed1977

Bilateral testicular biopsy in men with varicocele.

Fifty-two infertile men with varicoceles were subjected to bilateral testicular biopsy to detect the effect of the varicocele on each testis. The results indicate that varicocele can result in infertility primarily through sloughing of immature cells or through arrest of spermatogenesis at the spermatid or primary spermatocyte stage. The effect is bilateral but is more marked on the varicocele side. However, the presence of a varicocele could not explain the infertility of seven men with normal biopsies and of four men with a normal biopsy on the varicocele side and arrest on the other side.

Adult↗
PubMed1977

Is postoperative proximal decompression a necessary complement to elective colon resection?

Postoperative nasogastric suction is not a necessary complement to elective colon resection. We studied two groups of patients who had elective colon resection: nasogastric suction was used in the postoperative management of 53 patients, while 23 patients were managed without nasogastric suction. The morbidity and mortality rates were comparable in the two groups.

Colon↗