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S Al-Sarraj

Publications and source records attributed to S Al-Sarraj.

25 records · Page 2Linked to original sources
PubMed1986

Production of nitrosamines from ephedrine, pseudoephedrine and extracts of Ephedra foliata under physiological conditions.

N-Nitrosoephedrine (NEP) and N-nitrosopseudoephedrine (NPEP) were synthesised at 5 degrees C using different concentrations of various acids. The reaction with acetic acid gave the highest yield (85%) of N-nitrosamine. Ephedrine and pseudoephedrine were reacted with nitrite under physiological conditions (37 degrees C, pH 1-3) to form NEP and NPEP. The yield of NEP, which is a known carcinogen, and NPEP were the highest (18.5%) at pH 2. Aqueous and alcoholic extracts of Ephedra foliata (100 g dry wt), nitrosated under physiological conditions, produced 0.77 mg and 8.3 mg, respectively, as total nitrosamines. This indicated the potential of the nitrosamine formation from the plant extracts specified.

Chemical Phenomena↗
PubMed1975

The metabolism of chlorpromazine and promethazine to give new 'pink spots'.

1. The 'pink spots' observed in the in vivo and in vitro metabolism of chlorpromazine and promethazine were identified as N-oxidation products of 2-chlorophenothiazine and phenothizaine,, respectively. 2. Incubations of the latter two compounds with fortified hepatic fractions from rabbit and guinea-pig gave the corresponding hydroxylamines, the nitroxides which were purplish-pink and gave characteristic e.s.r. signals, and the N-hydroperoxides which were the major pink compounds and gave no e.s.r. signals. Each hydroxylamine was readily oxidized to an N-hydroperoxide in air and the latter readily reduced back in solution to the corresponding hydroxylamine by ascorbic acid. 3. The synthesis, chemical properties and the i.r., u.v., n.m.r., e.s.r., and mass spectra of the above compounds, their sulphoxides and phenothiazine-N-peroxides are reported.

Animals↗
PubMedDate not supplied

Specificity and sensitivity of betaAPP in head injury.

INTRODUCTION: Beta-amyloid precursor protein (betaAPP) expression has been found in traumatic brain injury, hypoxia, ischemia and infection which affect axonal transport. Although betaAPP is a sensitive marker for detecting axonal damage, it has become non-specific for a particular type of injury. The aim of this study was to identify a difference in the pattern, distribution and intensity of betaAPP expression in head injury compared to hypoxic/ischemic insults. MATERIALS AND METHODS: Thirteen primary head injury and 12 primary hypoxic/ischemic cases were selected. The anterior and posterior parts of corpus callosum, internal capsule (basal ganglia), middle cerebellar peduncles (cerebellum) and pons were examined and stained immunohistochemically for betaAPP antibody. A computerized system of image analysis was used to examine the intensity (strength of staining) and density (area fraction) of betaAPP. RESULTS: Significant differences were observed in the overall intensity and density of betaAPP expression (p < 0.05) and in all 5 brain regions in cases of head injury compared to the hypoxic/ischemic group (p < 0.05). Positive staining for betaAPP was found in all regions in all cases of head injury, however, 4 out of 12 cases of hypoxia/ischemia were positive for betaAPP. One case expressed positivity in all 5 regions, 2 cases exhibited positivity in the pons alone, with only 1 case exhibiting immunoreactivity in the posterior corpus callosum and internal capsule. Differences in the pattern of betaAPP expression identified a predominantly granular pattern with a dirty background seen in hypoxia/ischemia, while fusiform swellings, beaded and thick filaments with clear background were observed in head injury. CONCLUSION: There are differences in the pattern, distribution and intensity of betaAPP in head injury compared to hypoxia/ischemia. These could be due to pathophysiological differences. The results may be helpful in differentiating head injury from hypoxia in medicolegal cases.

Adolescent↗
PubMedDate not supplied

Subdural hematoma (SDH): assessment of macrophage reactivity within the dura mater and underlying hematoma.

OBJECTIVES: Macrophages are an inherent component of the dura mater, and can be characterised in cases of subdural hematoma (SDH) by their progressive and varying accumulation within areas of damage. Gross and histological methods used to determine the age of SDH are inexact. These are in part due to the active nature of such lesions and the diverse manner in which trauma victims respond to injury. Correct diagnosis has obvious medico-legal implications. However, there is as yet no specific diagnostic method that allows the age of SDH to be reliably determined. This study investigated the progressive and orderly pattern of reactivity of resident and infiltrating dural macrophages that occurs in response to injury associated with SDH. MATERIALS: 26 postmortem cases of traumatic SDH were examined with survival times (onset of trauma to death) ranging from a few hours and up to 31 days. METHODS: Macrophage reactivity associated with the dura mater and the underlying hematoma was determined using CD68 and MHC class II immunohistochemistry and the qualitative and quantitative findings compared with the presence of iron detected using conventional Perl's Prussian blue method. RESULTS: The results show that CD68 and MHC class II are differentially expressed within the dura mater and hematoma in SDH, and that the expression of MHC class II is markedly upregulated in the inner aspect of the dura mater within the initial 24 hours following injury. CD68 expression can be detected quantitatively in the hematoma, 24-48 hours after SDH, and within the dura following this period. Linear regression analysis further revealed a significant and positive association between the expression of MHC class II or CD68 antigens and the progressive survival of SDH up to 31 days post-injury, which was not seen with Perl's histochemical method. The expression of MHC class II antigen was a distinguishing, and quantifiable feature particularly localized within the inner aspect of the dura from a very early stage in the progression of SDH. Widespread, diffuse and cellular MHC class II reactivity was particularly noted within the inner aspect of the dura mater in cases of SDH with survival > 10 days. Since only a proportion of this widespread immunoreactivity was accounted for by macrophages (considering CD68 immunoreactivity), a large component of this activity was more likely to be due to the reorganisation and activation of fibroblasts within inner dural layers (dural border layer), known to upregulate expression of MHC class II molecules. CONCLUSIONS: The expression of CD68 and MHC class II antigens provides a more informative picture of the progression of pathology associated with SDH, and may be used in conjunction with other clinicopathological factors, in further investigations that attempt to date SDH according to defined histopathological characteristics.

Adolescent↗
PubMedDate not supplied

Rosenthal fiber encephalopathy presenting with demyelination and Rosenthal fibers in a solvent abuser: adult Alexander's disease?

We report a neuropathological case of the brain of a 22-year-old male solvent abuser. He had also been diagnosed as suffering from schizophrenia. Neurohistology revealed the presence of Rosenthal fibers (RFs) in subpial and perivascular collections in the medulla, the floor of the 3rd and 4th ventricles, and also in the spinal cord. There was mild demyelination in the frontal, temporal, and parietal lobes, as well as the left dorsal column in the spinal cord. There was bilateral basal ganglia calcification. Demyelination and RFs have been the hallmark of the diagnosis of adult Alexander's disease. We urge that these are insufficient criteria for this nosological category, and suggest the alternative and more appropriate label of Rosenthal fiber encephalopathy. In view of the known toxic, clinical effects of chronic solvent abuse, and the lack of knowledge of the neuropathological effects, we also tentatively note the association of the solvent abuse with the neuropathology, but are unable to assert any causal link.

Adult↗