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Biomedical subjects

S Attia

Publications and source records attributed to S Attia.

17 recordsLinked to original sources
PubMed2002

Intrinsic aging vs. photoaging: a comparative histopathological, immunohistochemical, and ultrastructural study of skin.

Cutaneous aging is a complex biological phenomenon affecting the different constituents of the skin. To compare the effects of intrinsic and extrinsic aging processes, a total of 83 biopsies were collected from sun-exposed and protected skin of healthy volunteers representing decades from the 1st to the 9th (6-84 years of age). Routine histopathology coupled with computer-assisted image analysis was used to assess epidermal changes. Immunoperoxidase techniques with antibodies against type I and type III collagens and elastin were used to quantitatively evaluate changes in collagen and elastic fibers and their ultrastructure was examined by transmission electron microscopy. Epidermal thickness was found to be constant in different decades in both sun-exposed and protected skin; however, it was significantly greater in sun-exposed skin (P = 0.0001). In protected skin, type I and III collagen staining was altered only after the 8th decade, while in sun-exposed skin the relative staining intensity significantly decreased from 82.5% and 80.4% in the 1st decade to 53.2% and 44.1% in the 9th decade, respectively (P = 0.0004 and 0.0008). In facial skin the collagen fiber architecture appeared disorganized after the 4th decade. The staining intensity of elastin in protected skin significantly decreased from 49.2% in the 1st decade to 30.4% in the 9th decade (P = 0.05), whereas in sun-exposed skin the intensity gradually increased from 56.5% in the 1st decade to 75.2% in the 9th decade (P = 0.001). The accumulated elastin in facial skin was morphologically abnormal and appeared to occupy the areas of lost collagen. Collectively, the aging processes, whether intrinsic or extrinsic, have both quantitative and qualitative effects on collagen and elastic fibers in the skin.

Adolescent↗
PubMed2001

Effect of chemicals on the duration of male meiosis in mice detected with laser scanning cytometry.

Aneuploidy studies in sperm such as the sperm-FISH assay require a precise knowledge of the duration of spermatogenesis, especially of the meiotic stages. This is important in order to sample sperm from the epididymis at appropriate intervals after animal treatment. However, aneugens may delay the cell cycle. The progression from meiotic divisions to epididymal sperm was determined by labelling the last S-phase before meiosis with the thymidine analogue 5-bromo-2'-deoxyuridine (BrdU) and treating the animals 13 days later with the test chemicals. In a time frame of 20--24 days after treatment, BrdU-containing sperm were identified with a FITC-labelled anti-BrdU antibody and green fluorescent sperm were scored with a laser scanning cytometer (LSC). We studied the effects of the chemicals acrylamide, colchicine, diazepam, griseofulvin, taxol, thiobendazole, trichlorfon and vinblastine on the duration of meiotic divisions in male mice. Colchicine treatment prolonged the duration of meiotic divisions by about 48 h. On days 21 and 22, the frequencies of BrdU-labelled sperm in the colchicine group were 11.7 and 9.4%, respectively, while they were 28.4 and 30.6%, respectively, in the concurrent controls (P > 0.01). On day 24 after treatment, the frequency of labelled sperm in the colchicine group reached the control level. Etoposide treatment resulted in an elevation of BrdU-labelled sperm at 23 rather than 22 days. The other chemicals showed no significant effect of prolonging meiotic cell cycle progression. On the basis of the colchicine and etoposide data, it is suggested that the effect of a chemical on the meiotic cell cycle progression is determined first in order to chose the appropriate sperm sampling time to detect aneuploidy induction.

Animals↗
PubMed1999

A spermine-deoxycholic acid conjugate based lipid as a transfecting agent.

Deoxycholic acid-spermine conjugate (DAS), which is composed of natural components (deoxycholic acid and spermine), was incorporated in liposomes and evaluated for its interaction with plasmid DNA (pDNA) and in vitro transfection efficiency. Electromicrographs demonstrated that DAS-pDNA complexes are spherical, compact and electronically dense compared to the toroidal shapes formed by the monovalent lipid 1,2-dioleoyl-3-trimethylammonium propane (DOTAP) and pDNA. In comparison to the singly charged, non-cholesterol based lipid (DOTAP), the multivalent lipid DAS had similar transfection efficiency in two cell lines. The monovalent sterol, deoxycholic acid propyldiamine conjugate (DAP) was not effective as a transfecting agent. This suggests that multivalent facial amphiphiles such as DAS may serve as excellent candidates for non-viral gene transfer and warrant further study.

Animals↗
PubMed1998

In vitro myotoxicity of selected cationic macromolecules used in non-viral gene delivery.

PURPOSE: Cationic lipid/DNA complexes have been proposed as a method of in vivo gene delivery via intravenous or intramuscular injection. A concern with using these polycationic molecules is whether they are associated with tissue toxicity at the injection site. Therefore, the objective of these studies was to investigate the myotoxic potential of selected non-viral gene delivery macromolecules (e.g., cationic lipids and polymers) with and without plasmid DNA (pDNA) in vitro. METHODS: Myotoxicity was assessed by the cumulative release of creatine kinase (CK) over 90 minutes from the isolated rodent extensor digitorum longus muscle into a carbogenated balanced salt solution (BBS, pH 7.4, 37 degrees C) following a 15 microL injection of the test formulation. Phenytoin (Dilantin) and normal saline served as positive and negative controls, respectively. RESULTS: The myotoxicity of plasmid DNA (pDNA, approximately 5000bp, 1 mg/ml) was not statistically different from normal saline. However, the myotoxicity of Dilantin was 16-times higher than either normal saline or pDNA (p < 0.05). Cationic liposomes were found to be less myotoxic than polylysine and PAMAM dendrimers. Polylysine's myotoxicity was found to be dependent upon concentration and molecular weight. The myotoxicity of formulations of cationic liposomes(s), lower molecular weight polylysine (25,000) and higher concentration of PAMAM dendrimers with pDNA were found to be statistically less significant than those formulations without pDNA. CONCLUSIONS: The cationic liposomes were less myotoxic compared to the dendrimers and polylysine. Myotoxicity was dependent upon the type of cationic lipid macromolecule, concentration, molecular weight and the presence of pDNA. A possible explanation for this reduced tissue damage in cationic lipids complexed with pDNA is that the formation of complex reduces the overall positive charge of the injectable system resulting in less damage.

Animals↗
PubMed1993

Nonemergent forcible medication in an acute hospital.

Nonemergent forcible medication is a controversial procedure that has received somewhat less study in acute hospitals and in states where a simple in-house "treatment-driven" clinical review procedure is followed. We reviewed the charts of all patients so medicated by the New Jersey "Rennie" process on a large general acute adult psychiatric service, finding 43 (3%) of 1420 admitted patients so treated. Compared with a population of next-admitted individuals, these "Rennie" patients more frequently had previously required extended emergent forcible medication, had significantly longer hospitalizations (70 versus 26 days), not accounted for by the duration of treatment refusal, but improved with treatment so that almost all were discharged directly back to the community. Rennie patients appeared more likely to be diagnosed with schizophrenia and were significantly more likely to have a known history of assault, threatened assault, or property damage, but significantly less likely to have a known history of suicide threat or attempt. They were also significantly less likely to have a principal or secondary diagnosis of personality disorder or substance use disorder.

Adult↗
PubMed1985

HLA-antigens in Guillain-Barré syndrome.

A microlymphocytotoxicity test determined serologically the frequency of HLA antigens in 32 patients with Guillain-Barré syndrome and in 234 healthy control subjects. The results demonstrated significantly increased frequencies of A3 and B8. The relative risk was estimated to be 9.6 and 4.6 for the A3 and B8 antigens, respectively. Study of the gametic association revealed weak positive linkage disequilibrium and biological association. The results are discussed, and it is concluded that the aberrant genetic make-up of the patients makes them more susceptible to develop the syndrome after exposure to the environmental factor(s).

Child↗
PubMedDate not supplied

Valsalva retinopathy induced by labour.

PURPOSE: To describe a patient with Valsalva retinopathy induced by labour. METHODS: Case report. RESULTS: A 29-year-old woman at her second pregnancy complained of a sudden loss of vision in her left eye during spontaneous labour. Visual acuity was reduced to counting fingers. Funduscopy revealed a large preretinal hemorrhage at the macula in the left eye. Three weeks after delivery, the hematoma was treated with Nd:YAG laser. Two weeks after treatment, visual acuity was 20/20 and the premacular hemorrhage had resolved. CONCLUSIONS: A rise in intra-abdominal pressure during labour may result in Valsalva retinopathy. Nd:YAG laser may be useful in treating such hemorrhage.

Adult↗
PubMedDate not supplied

[Clinical and therapeutic profile of broncho-pulmonary adenocarcinomas].

Broncho-pulmonary adenocarcinoma get interest since many years because his increased prevalence. Between december 1998 and January 70 male patients, mean age 56 years, with broncho-pulmonary adenocarcinome were collected retrospectively. The epidémiologic, clinic, radiologic and evolutive data of this pathologic form of cancer was studied. The ratio increased from 10% in 1988 to 14% in 1996. Clinic manifestations was common. Radiologic features was represented essentially by a unique (82%) and péripheric (56%) opacity. The diagnosis, based on cytologic and histologic data, was assessed in 39% of cases by endoscopic biopsy. The investigation for the primitive neoplasic process was made in 18% of patients and found only 2 cases of extra-pulmonary neoplastic process. Curative treatment based on surgery is performed only in 28% of our patients regarding the advanced stage of disease explaining the low survival rates.

Adenocarcinoma↗
PubMedDate not supplied

[A rare complication of antineoplastic BCG therapy: pulmonary tuberculosis].

Local treatment with intra vesical BCG for bladder carcinoma have few complications. Pulmonary side effects are rare, like interstitial pneumonitis. We report a case of a 77-year-old man, treated with BCG for bladder carcinoma who developed illness and tumoral chest-X-ray opacity. Mycobacterium tuberculosis bovis was isolated in culture and 2 years after in sputum. Physio pathologic mechanism of pulmonary features remains controversial, however this case suggest that lung lesions can be result of an infection process.

Aged↗