Biomedical subjects

M Samir

Publications and source records attributed to M Samir.

5 recordsLinked to original sources

PubMed1999

Fate of cartilage material used in middle ear surgery light and electron microscopy study.

OBJECTIVE: To evaluate the fate of autograft and homograft cartilage used in the middle ear. METHOD: Animal experimental study was carried out on 20 healthy guinea pigs by implanting small pieces of auto- and homograft costal cartilage in the middle ears for different periods of time (1, 3 and 6 months). The grafts were removed and examined by light and electron microscopy. Cartilage autografts, obtained from seven human cases at revision tympanoplasty, were also examined by light and electron microscopy. RESULTS: In the animal experimental study the chondrocytes were degenerated while the matrix was preserved in both auto- and homograft specimens. The homografts were as good as the autografts as in both cases the cartilage matrix was preserved. In the human specimens obtained after 10-15 months of implantation (six cases), the matrix was preserved, the lacunae were empty and the chondrocytes were degenerated. The specimen removed after 31/2 years (one case) showed viable chondrocytes of big size with defined cell organelles. CONCLUSION: This work provides evidence for the beneficial role of cartilage in middle ear surgery as the matrix retained its structure. There is also a possibility for the chondrocytes to remain viable for a long time after implantation. It seems also that homograft cartilage is a good option during tympanoplasty and is comparable to autografts. In the animal study the homografts were as good as the autografts as in both cases cartilage matrix was preserved.

Animals↗

PubMed1999

Thiobarbituric acid reactive substances in patients with laryngeal cancer.

The purpose of this study was to measure the level of thiobarbituric acid reactive substances (TBARS), which are products of lipid peroxidation, as a reflection of oxidative status in 30 patients with laryngeal cancer. The TBARS were measured 1 day before surgery and 3 weeks after laryngectomy compared to 30 normal control subjects by the thiobarbituric acid (TBA) test using spectrophotometry. The TBARS levels were significantly elevated in patients with laryngeal cancer compared to the controls (18.4 +/- 3.13 mumol/l versus 7.75 +/- 1.9 mumol/l; P < 0.05). There were no differences in the TBARS levels in relation to T staging, N staging, or degree of differentiation. Among patients with laryngeal cancer smokers had slightly higher TBARS levels. Comparison of the paired observations of laryngeal cancer larynx before and after operation revealed a significant rise in the TBARS levels after laryngectomy. Tissue damage resulting from surgery is the most probable explanation for this rise. The state of altered lipid peroxidation detected in our patients might be related to a deficient antioxidant status. The role of antioxidants in the prevention of laryngeal cancer among high risk patients is worth studying.

Carcinoma, Squamous Cell↗

PubMed1998

Transient otoacoustic emissions in children with chronic renal failure.

This study was conducted on 34 children with chronic renal failure: 27 on regular haemodialysis and seven on conservative treatment. Twenty normal healthy children served as controls. They were subjected to clinical examination including otoscopic examination, basic audiological assessment and transient otoacoustic emission testing (TOAE). Four patients had a conductive hearing loss and five had a bilateral moderately severe high frequency sensory neural hearing loss. TOAE testing was carried out for the rest whose ears displayed normal hearing. No response (fail) was obtained in 8% of them but in none of the controls and a partial pass response in 38% versus 10% of controls (P < 0.001). Cochlear dysfunction was significant only at low frequency levels. The mean overall echo-level and reproducibility were significantly lower in patients than in controls. The same holds true for the subgroup of patients on haemodialysis but not for those on conservative treatment. The overall echo-levels did not correlate with serum urea, creatinine, sodium or potassium.

Acoustic Impedance Tests↗

PubMed1998

Serum selenium levels in multinodular goitre.

Serum selenium levels were measured in 22 patients with a multinodular goitre and compared to 15 normal controls using atomic absorption spectrophotometry. The serum selenium was significantly low in these patients (patients' mean = 9.6 +/- 1.24 mcg/l, versus control mean = 11.7 +/- 1.64 mcg/l and P < 0.005). Serum T4 and T3 were within the normal range in all patients and controls. Their levels correlated positively, though weakly, with the serum selenium levels (r = 0.4 and 0.36, respectively). The control selenium levels in this study were lower than the reported figures from some European countries, but they were close to those from other studies in Egypt. It seems that Egypt is a low selenium area. A wide-scale epidemiological study is recommended, together with the examination of the possible preventive role of selenium supplementation in areas of endemic goitre.

Adult↗

PubMed1997

Air pollution in relation to allergic and nonallergic rhinitis.

OBJECTIVE: To investigate the relationship between allergic and nonallergic rhinitis and the exposure to air pollution. DESIGN: Blood cadmium levels were measured in 30 patients with allergic rhinitis, 30 patients with nonallergic rhinitis, and 16 normal control subjects using atomic absorption spectrophotometry. The cadmium level was used as a parameter of degree and proximity of exposure to air pollution from various sources. SETTING: Ain Shams University, a tertiary care referral center in Cairo, Egypt. RESULTS: Blood cadmium levels were significantly high in the allergic rhinitis group compared with the nonallergic rhinitis and control groups (P < .001). The mean blood cadmium level in the nonallergic rhinitis group was higher than that in the controls, yet the difference was statistically insignificant. Also, cadmium levels were above the 95% confidence interval in only 7% of this group. Blood cadmium levels in the controls (16.33 +/- 2.98 [SD] micromol/L [183.62 +/- 33.5 micrograms/dL) were much higher than those reported from areas of high cadmium pollution (0.88-2.66 micromol/L [10-30 micrograms/dL]). CONCLUSION: The significantly high blood cadmium levels in patients with allergic rhinitis may reflect a causal relationship between air pollution and this condition. The exact mechanism, however, remains to be determined. In nonallergic rhinitis, it seems that the contribution of air pollution as a predisposing factor is small compared with the other known predisposing factors.

Adolescent↗