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M H Ali

Publications and source records attributed to M H Ali.

At least 37 records · Page 2Linked to original sources
PubMed1990

Metabolism studies of the antischistosomal drug praziquantel using tandem mass spectrometry: qualitative identification of 17 hydroxylated metabolites from mouse urine.

Schistosomiasis is a parasitic liver infection which is known to affect many aspects of drug metabolism. Praziquantel (PZQ) is the drug of choice for treating this disease. PZQ is known to be highly metabolized, but the effect of the disease on its metabolism has not been investigated. Control mice and mice infected with Schistosoma mansoni were dosed with PZQ and their urines were examined for the presence of metabolites using a triple-quadrupole mass spectrometer (tandem mass spectrometer). The collisionally induced dissociation of PZQ was remarkable in its structurally significant fragments. From this we were able to identify 17 hydroxylated metabolites of PZQ from purified urine samples without further chemical separation, including three monohydroxylated, six dihydroxylated, and eight trihydroxylated metabolites. There were no qualitative differences in metabolite production between control and infected animals.

Animals↗
PubMed1990

Metabolism studies of the antischistosomal drug praziquantel using tandem mass spectrometry: distribution of parent drug and ten metabolites obtained from control and schistosome-infected mouse urine.

The collisionally activated dissociation spectrum of the antischistosomal drug praziquantel (PZQ) has many structure-specific fragmentations which permit identification of PZQ and seventeen of its hydroxylated metabolites in mouse urine. These fragmentations may also be used to quantify the metabolic pattern of PZQ. In the present study, a triple-quadrupole mass spectrometer system has been used to generate [M + H]+ ions for PZQ and its monohydroxy, dihydroxy and trihydroxy metabolites which yield daughter ions capable of quantifying PZQ and ten of these metabolites. The goal of these experiments was to evaluate the effect of this hepatic infection on drug metabolism. This was accomplished in two steps. First, the amount of unmetabolized, mono- and dihydroxylated PZQ was established from the [M + H]+ ions. Then the specific metabolites at each level of hydroxylation were determined from daughter ion spectra. The product of these two values produces the metabolite pattern. The reproducibility of these assays ranged from good, with a coefficient of variation of 3% for the most abundant metabolite, to poor (43%) for PZQ, which is only 1% of the total elimination pattern. The excretion of unchanged PZQ and two dihydroxylated metabolites was enhanced in animals bearing schistosomiasis compared to control mice, while a third dihydroxylated metabolite was depressed.

Animals↗
PubMed1990

Angiolymphoid hyperplasia with eosinophilia associated with tetanus toxoid vaccination.

Three cases of angiolymphoid hyperplasia with eosinophilia are reported at the site of tetanus toxoid vaccination. All presented as nodules on the upper arm, a known adverse effect of the vaccine following superficial inoculation. Histologically the nodules showed numerous small and medium sized vessels, some lined by hyperplastic endothelial cells with perivascular lymphocytic cuffing and an inflammatory infiltrate of plasma cells, eosinophils and scattered mast cells. Lymphoid follicles replete with germinal centres were identified in the dermis and subcutaneous tissue. Immunostaining revealed a polytypic lymphoplasmacytic infiltrate and a curious IgE reticulated pattern within the germinal centres, a feature described in both Kimura's disease and angiolymphoid hyperplasia. The present study suggests that atopic reaction to tetanus toxoid may be an aetiological factor in some cases of angiolymphoid hyperplasia.

Adult↗
PubMed1989

Extramedullary plasmacytoma of skeletal muscle. A case report with immunocytochemistry and ultrastructural study.

An uncommon origin of a rare tumor is described in a 60-year-old white man. Extramedullary plasmacytoma was localized in the left biceps muscle. Tumor immunostaining corresponded with immunocharacterization of the atypical midgamma band on electrophoresis or the serum monoclonal M protein of IgG kappa. The latter disappeared 6 months after the operation. The diagnosis was confirmed ultrastructurally.

Arm↗
PubMed1989

Human eosinophil cytotoxicity-enhancing factor. Purification, physical characteristics, and partial amino acid sequence of an active polypeptide.

Medium conditioned by PMA/LPS-stimulated U937 cells was processed for the purification of an eosinophil cytotoxicity-enhancing factor (ECEF) by the following sequence: 1) phenyl-Sepharose chromatography; 2) DEAE-cartridge chromatography; 3) preparative SDS-gel electrophoresis; and 4) reversed-phase HPLC. This resulted in the isolation of a 10 kDa polypeptide with ECEF activity. Purified material from 21 different preparations enhanced eosinophil killing of antibody-coated Schistosoma mansoni schistosomula by a mean of 206% (increase from 13.2 +/- 7.9% to 40.4 +/- 20.2% of targets killed, p less than 0.0001). Activity was maximal at a concentration of 20 ng ECEF polypeptide/ml and half-maximal between 0.8 and 4 ng/ml. Antibody specific for the 10 kDa polypeptide precipitated ECEF activity from a crude preparation and, by Western blot analysis, reacted only with a 10 kDa species in that preparation. The following N-terminal amino acid sequence was determined for the purified polypeptide: Val-Lys-Gln-Ile-Glu-Ser-Lys-Thr-Ala-Phe-Gln-Lys-Ala-Leu- -Ala- Gly- -Lys-Leu.... Computer search showed that this sequence is unrelated to other known protein sequences. Thus, the ECEF polypeptide is a newly defined monokine, with the ability to enhance eosinophil cytotoxic function in vitro. This monokine may be an important regulator of eosinophil function in inflammation in vivo.

Amino Acid Sequence↗
PubMed1989

Idiopathic scrotal calcinosis: a possible aetiology reaffirmed.

Idiopathic scrotal calcinosis is characterised by the presence of multiple firm scrotal nodules of unknown or disputed aetiology. Only 55 cases have been reported in the literature since the first description by Lewinski (1883). We report an additional five patients. We have reviewed the literature exhaustively and our findings support the suggestion that the lesions of "idiopathic" scrotal calcinosis result simply from dystrophic calcification of epidermal cysts.

Adult↗
PubMed1989

Paraganglioma presenting with an aortic aneurysm.

The concurrence of a paraganglioma of the organ of Zuckerkandl and an abdominal aortic aneurysm is reported in a 72-year-old caucasian male. Computerized tomography scan confirmed the aneurysm and noted a well-circumscribed tumour of the aneurysmal wall. At operation, the tumour was identified and excised with part of the aneurysmal wall. The tumour exhibited all the features of a paraganglioma while the vessel wall showed atherosclerosis and secondary degenerative changes. The features of the aortico-sympathetic group of paragangliomas are discussed.

Aged↗
PubMed1989

Lymph node pathology in Henoch-Schönlein purpura.

This report describes two cases of Henoch-Schönlein purpura with unusual lymph node pathology. The patients presented with severe colicky abdominal pain mimicking acute appendicitis but a normal appendix was removed in each case. Enlarged mesenteric lymph nodes were removed, with a clinical suspicion of Yersinia infection. Cultures and serology were negative. Histological examination of the lymph nodes revealed follicular granulomas, follicular microabscesses and leucocytoclastic vasculitis. Immunohistochemical studies revealed deposition of IgA, IgG and C3 in the vessel walls, the finding of IgA supporting a diagnosis of Henoch-Schönlein purpura.

Adult↗
PubMed1988

Tumour thickness in malignant melanoma: the limitations of frozen section.

This paper reports a prospective study to compare maximal tumour thickness values of the same lesion obtained by frozen and paraffin sections in 20 patients with malignant melanoma over a one-year period. Significant differences were found between tumour thickness values obtained by frozen section and paraffin section. There was no constant relationship between the two sets of values. As present prognostic and therapeutic criteria are based on tumour thickness measurements obtained from paraffin sections, we recommend that clinical decisions should not be based on results obtained from frozen sections.

Adult↗
PubMed1988

Merkel-cell carcinoma of the pinna.

Merkel-Cell carcinoma is a rare malignant skin tumour. It was first described as 'Trabecular Carcinoma' by Toker in 1972. Since then many reports have appeared in the literature, mainly in the dermatology, pathology and to a lesser extent, in the plastic surgery journals. Surprisingly, the topic is rarely discussed in the otolaryngology literature, though nearly fifty per cent of these tumours arise in the head and neck.

Adenocarcinoma↗
PubMed1988

Vascular leiomyoma of the inferior turbinate--report of a case and review of the literature.

Leiomyoma of the nose and paranasal sinuses is rare. It constitutes about 1 per cent of all benign tumours. This is due to the paucity of smooth muscle in the nose. In this paper, the authors present one case of vascular leiomyoma which arose in the inferior turbinate in a 64-year-old lady. It was treated by partial turbinectomy with the relief of her symptoms of nasal obstruction, epistaxis and facial pain. The English literature on the topic is reviewed.

Female↗
PubMed1988

An enzyme-linked immunosorbent assay for the serodiagnosis of Campylobacter pylori-associated gastritis.

An ELISA system, using an acid extractable cell surface C. pylori antigen, has been used to detect anti-C. pylori antibodies in 176 endoscoped patients. The antibody concentration was related to histological diagnosis and colonisation with Campylobacter-like organisms. The criteria for sero-positivity was determined from the median antibody concentration in a group of 368 non-endoscoped control patients. The specificity and sensitivity of the sero-diagnostic assay for histological gastritis in antral biopsies was 83.0% and 95.6% respectively. The positive (79.3%) and negative predictive values (94.3%) indicate that such a sero-diagnostic assay could be used to screen patients prior to endoscopy.

Adult↗
PubMed1988

Evaluation of the laboratory diagnosis of vaginal trichomoniasis in Khartoum.

A total of 403 vaginal discharge specimens were investigated for Trichomonas vaginalis using fresh wet-mounts, culture and Papanicolaou staining. By fresh wet-mounts, 58 specimens (14.4%) were found harbouring the parasite. On culture 67 isolates (16.7%) were identified. Both wet-mount and cultural procedures detected 18.3% positive isolates. Papanicolaou staining detected 40 positive cases (9.9%) from the patients investigated. Two culture media were tried in this study to isolate T. vaginalis, namely Lumsden's medium and Diamond's medium. Their efficacy was found to be 16.9% and 14.8%, respectively.

Adolescent↗
PubMed1988

Prevalence of Campylobacter pylori in duodenal and gastric mucosa--relationship to inflammation.

Endoscopic biopsies from 310 patients were studied for the presence of Campylobacter pylori (Cp). In the first group of 150 patients duodenal and antral biopsies were obtained and in the second (160 patients) biopsies were taken from various sites in the stomach including the antrum, incisura, body and fundus. In the duodenum there was a strong association with active inflammation and the presence of gastric metaplasia. Cp were never seen in the normal duodenum. In the stomach Cp presence was associated with gastritis irrespective of severity and site, but was absent in areas showing intestinal metaplasia. Cp were seen in histologically normal biopsies from all areas of the stomach but were significantly more common in normal fundal than normal antral mucosa.

Biopsy↗
PubMed1987

Verrucous carcinoma of the nasal septum.

A case of verrucous carcinoma of the nose is presented. Initially two pathologists described the lesion as benign. The tumour was excised with free margins through a lateral rhinotomy, with a successful outcome. The literature on the topic has been reviewed. Deep wide-based biopsy should always be considered if such a lesion is not to be missed on the first consultation. Surgery in resectable lesions offers the best chance of survival in verrucous carcinoma of the nose.

Aged↗
PubMed1986

Aggressive pilomatrixoma in a child: a case report.

Calcifying epitheliomas of Malherbe (pilomatrixomas) are benign calcifying tumours that arise from the hair matrix and present as a slow-growing dermal or subcutaneous mass most commonly located in the head and neck. Recurrences after tumour removal are rare. There have been reports in the past of invasive pilomatrixoma in the pre-auricular area (Krausen et al., 1974; Rothman et al., 1976; Sasaki et al., 1976; Arole et al., 1983), as well as other locations such as the right arm (Gromiko, 1927) and the upper back (Lopansri and Mihm, 1980). Two cases were also reported in adults by Weedon et al. in 1980. None of these tumours has occurred in children.

Child↗