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Biomedical subjects

F Hassan

Publications and source records attributed to F Hassan.

36 records · Page 2Linked to original sources
PubMed1985

Purification and characterization of pyocins from Pseudomonas aeruginosa.

Three types of pyocins were found in Pseudomonas aeruginosa strain 986 and named pyocin type P25, P50, and P70. Production of these types was inducible by UV irradiation. Their molar mass was estimated. The pyocins obtained were different from the known pyocins R, S, and F in their chemical and physical properties. No immunological cross reaction was observed among these pyocins.

Amino Acids↗
PubMed1984

An evaluation of quantitative techniques for Schistosoma haematobium eggs in urine preserved with carbolfuchsin.

The objective of this study was to determine a suitable method for quantitating Schistosoma haematobium eggs in urine specimens preserved in carbolfuchsin. Using a 0.002% carbolfuchsin-phenol-alcohol solution as a stain/preservative for urine obtained from 30 patients infected with S. haematobium, we compared egg counts obtained with four quantitative techniques: Nytrel filtration, Nuclepore filtration, suction filtration and centrifugation. Centrifugation gave statistically higher values than all other techniques for absolute number of eggs recovered in the preserved urine. We also measure a statistical difference between the counts obtained from Nuclepore filtration of fresh urine and those established on an equivalent volume of preserved urine by Nuclepore and Nytrel filtration. The preserved urine frequently caused obstruction of both Nuclepore filters and Whatman No. 1 filters (used in suction filtration), rendering them technically difficult to use and less satisfactory than other methods. From the techniques we examined, we conclude that in field studies where preservation of urine is necessary, preparation of Nuclepore filters with fresh urine, or centrifugation of a carbolfuchsin-preserved urine, are the methods of choice for quantitation of specimens.

Animals↗
PubMed1981

Acid and alkaline phosphomonoesterases in Egyptian snake venoms.

Non-specific acid and alkaline phosphomonoesterases could be demonstrated in two viperids (Cerastes cerastes and Cerastes vipers) and two elapids (Naja haje and Naja nigricollis). The latter could be a natural source for the production of these enzymes. The activities of both enzymes in elapids were greater than in viperids. N. nigricollis was the only to show acid phosphatase activity exceeding its alkaline one. The optimum pH values recorded for acid phosphatase was 4.0 and 4.9 and for alkaline phosphatase 9.0 and 10.0 in viperids and elapids, respectively. Optimum substrate concentration for both enzymes in viperids was 0.01 M, while for acid phosphatase in N. haje and N. nigricollis it was 0.125 and 0.150 M; and for their alkaline phosphatases the values were 0.150 and 0.125 M, respectively. Mg++ behaved as an activator for both enzymes in all venoms investigated, while Zn++ showed either no or slight activating effect. Fluoride ions as well as EDTA showed certain inhibitory action. Both enzymes in the crude venoms were heat-labile.

Acid Phosphatase↗
PubMed1981

Congo/Crimean haemorrhagic fever in Iraq.

Congo/Crimean haemorrhagic fever was recognized for the first time in Iraq in 1979. The first case was reported on 3 September 1979 and since then a further 9 patients have been investigated. Eight patients gave a history of previous contact with sheep or cattle, while 2 patients, a resident doctor and an auxiliary nurse, acquired their infections in hospital by direct contact with patients. The causal virus was isolated from patients' blood and postmortem liver specimens. The virus isolates were found to be closely related if not identical serologically to members of the Congo/Crimean haemorrhagic fever virus group. Eight of the patients had no epidemiological relationship to one another and lived in widely separated areas around Baghdad and Ramadi (110 km to the west of Baghdad).

Adolescent↗
PubMed1980

Biochemical properties of Egyptian Cerastes venoms in relation to geographic distribution.

Total proteins, electrophoretic analysis, biological lethality, and phospholipase activity of five members of the Cerastes-viper species living along the Nile Valley were investigated. Elevation of environmental temperature was accompanied with high values for these indices. It is concluded that zoological distribution and environmental conditions could influence the overall biological behaviour of snake venoms of the same species.

Animals↗
PubMed1980

Comparative studies on Egyptian elapid venoms.

The immunological properties of Naja haje from Western Desert, Naja haje of the Nile Delta, Naja nigricollis from Upper Egypt and Walternnesia aegyptia from Sinai Desert were compared using horse serum antivenin prepared from the Delta Naja haje venom. All elapid venoms showed very similar precipitin lines with immunodiffusion or immunoelectrophoresis on agar gel. Results of cellulose-acetate electrophoresis showed either different concentration of certain similar protein components or the absence of some major protein fractions. However, different migration and localization of protein components were observed. LD50 of the 4 elapids and their degree of lethality was determined. Naja haje (Delta) antivenin had different degree of neutralization capacity on the investigated elapid venoms. No correlation between immunodiffusion similarities and the degree of neutralization could be deducted.

Animals↗
PubMed1979

Evaluation of enzyme linked immunosorbent assay in the immunodiagnosis of schistosomiasis.

Eighty-six bilharzial patients divided into 5 clinical groups were studied. Enzyme linked immunosorbent assay (ELISA), indirect fluorescent antibody (IFA) and indirect haemagglutination (IHA) test were performed for all the patients. ELISA gave the most sensitive results (82.6% and 80.2% positivity rate in Egypt and Lille respectively), followed by IFA (79.1% positivity rate) and IHA (77.9% and 75.6% positivity rate in Egypt and Lille respectively). The humoral antibodies detected by all methods (ELISA, IFA and IHA) showed increasing values with the progress of the disease which is parallel to the antigenicity of the disease. Both the positivity rate and the mean value of antibody titres recorded by the 3 diagnostic techniques (ELISA, IFA and IHA) were significantly higher in mansoni than haematobium infection. This may be explained by species specificity of antibody response. The superiority of ELISA over IFA and IHA techniques was discussed.

Adolescent↗
PubMed1976

Immunological properties of antivenins. II. Univalent Naja haje antivenin.

A purified Naja haje antivenin was tested against Egyptian N. haje and N. nigricollis venoms, Indian N. naja venom, Iranian N. naja oxiana, Vipera lebetina, and V. persica venoms, and Echis carinatus venom from both Iran and Egypt. The different elapid venoms, with the exception of that of N. naja oxiana, showed a considerable number of identical and similar precipitin components by immunodiffusion and immunoelectrophoresis. On the other hand, only a few identical and partially identical lines were detected when this antiserum was tested against the viper venoms. Cross neutralization tests in mice showed variable degrees of protection by the antiserum against the different venoms studied; there was no direct correlation with the immunodiffusion results.

Antigen-Antibody Reactions↗
PubMedDate not supplied

Visceral protothecosis mimicking sclerosing cholangitis in an immunocompetent host: successful antifungal therapy.

A healthy 39-year-old man who had clinical findings consistent with sclerosing cholangitis was found to have systemic protothecosis at surgery. Severe granulomatous inflammation and palpable nodules were found in the gallbladder, on the surface of the liver, and in the duodenum. Prototheca wickerhamii was detected in biopsied specimens and stool; the titer of indirect fluorescent antibody to this organism was 1:2,000. The patient recovered after a short course of treatment with amphotericin B and 3 months of oral therapy with ketoconazole. He had no other concurrent illness and had no abnormality in his immune system. This is the second reported human case of systemic protothecosis. An elevated IgG level, an elevated erythrocyte sedimentation rate, eosinophilia, and abnormal levels of enzymes in the liver were found in both cases. Protothecosis should be considered in the differential diagnosis of hepatic and biliary inflammatory diseases of uncertain etiology.

Adult↗
PubMedDate not supplied

[Lichen pemphigoid associated with developing hepatitis B in a child].

INTRODUCTION: Lichen planus pemphigoides is a rare acquired auto-immune bullous dermatosis which usually affects adults. Only four cases have been reported in children. We describe a new case of lichen planus pemphigoides in a child unusual by its association with an evolutive hepatitis B and by the occurrence of a lichen planus relapse. CASE REPORT: A 10-year-old African boy has been seen for a pruritic dermatosis with papular lichenoid lesions on the trunk and the limbs and blisters on the lower limbs, both arise on lichen planus lesions and normal skin. The diagnosis of lichen planus pemphigoides was confirmed by histology which showed the features of lichen planus on a papule and of a sub-epidermal split on a bulla and by direct and indirect immunofluorescent studies which revealed an IgG and C3 linear deposit at the dermo-epidermal junction and the presence of circulating IgG anti-basement membrane zone antibodies. Laboratory investigations showed an evolutive hepatitis B (HBsAg +). Healing was obtained by dapsone and topical steroid therapy. Eight months after withdrawal of treatment the patient presented a non-bullous relapse of lichen planus. The histology showed a typical aspect of lichen planus and the immunofluorescence studies were negative. The hepatitis B serology was unchanged. The lesions rapidly improved with topical steroid and coaltar. One year later the patient exhibited few slight lichen planus lesions on the limbs and the hepatitis B serology showed the onset of sero-conversion. DISCUSSION: Lichen planus and lichen planus pemphigoides are probably variants of the same disease. Their successive occurrence in our case report favours this hypothesis as does the association with an hepatitis B.

Administration, Cutaneous↗
PubMedDate not supplied

Comparative study between sonography, pathology and UGP in women with perimenopausal bleeding.

Adenocarcinoma is the commonest primary malignancy encountered in the endometrium. Adenomatous hyperplasia represents an important precancerous endometrial lesion. In this study, different techniques have been applied in a trial to early detect endometrial carcinoma and to distinguish between hyperplasia with minimal and high risk of progression to endometrial adenocarcinoma. Eighty women were included in this study and classified into 4 groups: 10 with adenocarcinoma, 28 with simple hyperplasia, 12 with hyperplasia with atypia and 30 normal healthy women. All individuals were subjected to Doppler endovaginal ultrasonography (EVS) for endometrial thickness and uterine artery resistance index (RI). Endometrial biopsy was taken for histopathological examination and DNA analysis. 24-hr urine was collected for the estimation of UGP by ELISA using reagents supplied by Ciba Corning Diagnostica, Alameda, CA, USA (Triton UGP-EIA). On referring to histopathological findings, no single parameter was seen to be specific and sensitive enough to differentiate between benign and malignant endometrial lesions. Doppler endovaginal ultrasonography could detect 76% of endometrial abnormalities. DNA ploidy and UGP showed equal sensitivity rate (60%) in endometrial carcinoma but DNA ploidy was more specific than UGP (0% and 10% false positivity in benign endometrial diseases respectively.

Adenocarcinoma↗