PubMed Health⌕ Search

Biomedical subjects

S Malekzadeh

Publications and source records attributed to S Malekzadeh.

7 recordsLinked to original sources

In vivo analysis of bacterial biofilm formation on facial plastic bioimplants.

OBJECTIVES: This study examines the formation of biofilm on biomaterials commonly used in facial plastics and reconstruction including titanium, silicone, ion-bombarded silicone (Ultrasil), e-PTFE (Gore-Tex), e-PTFE with silver/chlorhexidine (Gore-Tex Plus), and PHDPE (Medpor). METHODS: These biomaterials were implanted subcutaneously in the dorsum of 11 guinea pigs after contamination with Staphylococcus aureus and examined with scanning electron microscopy after 7 days. Wounds were also inspected for infection and extrusion rates. RESULTS: Results show biofilm formation on titanium, silicone, ion-bombarded silicone, e-PTFE, and PHDPE associated with high rates of extrusion and infection. Implants of e-PTFE with silver/chlorhexidine, on the other hand, appeared resistant to biofilm formation and demonstrated significantly lower rates of extrusion and infection. CONCLUSIONS: Contamination of bioimplants in vivo leads to formation of bacterial biofilm on the surface of the biomaterial, causing infection, pus formation, and extrusion. The authors hypothesize that the antiseptic agents impregnated in the biomaterial form a protective coat of silver, chlorhexidine, and inflammatory cells that inhibits initial bacterial adhesion to the biomaterial surface.

Animals↗

Rejuvenation of the upper arm.

During the course of life, the upper arm demonstrates skin relaxation and fat deposits that become increasingly evident, particularly with age. However, the degree of skin ptosis and accumulation of subcutaneous fat varies from patient to patient. Therefore, it is critical to evaluate each patient individually, to inform the patient of the available options, and to tailor the procedure to his or her needs. We have described four categories of upper-arm problems. Patients with minimal to moderate subcutaneous fat and minimal skin laxity generally do well with circumferential lipectomy alone. With an increased amount of subcutaneous fat and more pronounced skin laxity, suction lipectomy in conjunction with a "ridge" provides good results, with a well hidden scar in the axilla. In the obese patient in whom skin laxity becomes much more noticeable after suction lipectomy, we recommend a purse-string closure of the modest brachioplasty incision to decrease the scar size. In those patients who have minimal fat but extensive skin laxity, a traditional brachioplasty cannot be avoided. Carefully selected and properly informed patients will result in an extremely high satisfaction rate. The techniques and guidelines described are designed to provide simple, easily performed procedures with minimal complications that safely and effectively rejuvenate the upper arm.

Adipose Tissue↗

Composition of atherosclerotic plaques in the four major epicardial coronary arteries in patients greater than or equal to 90 years of age.

The composition of atherosclerotic plaques in 733 five-mm segments of the 4 major (left main, left anterior descending, left circumflex and right) epicardial coronary arteries of 18 patients greater than or equal to 90 years of age was determined by computerized planimetric analysis. By analysis of all coronary segments of all patients greater than 90, the plaques consisted primarily of fibrous tissue (87 +/- 8%) with calcific deposits (7 +/- 6%), pultaceous debris (5 +/- 4%) and foam cells (1 +/- 1%) occupying a much smaller percentage of plaque area. Analysis of composition according to the 4 degrees of luminal cross-sectional area narrowing revealed marked step-wise increases in pultaceous debris (from 0 +/- 0% at 0 to 25% narrowing to 18 +/- 22% at 76 to 100% narrowing, p = 0.0001) and calcific deposits (from 0 +/- 0 to 10 +/- 15%, p = 0.002), and decreases in fibrous tissue (from 99 +/- 3 to 71 +/- 23%, p = 0.0001) and area occupied by the media (from 35 +/- 8 to 16 +/- 8%, p = 0.0001). When the analysis was restricted to sections narrowed greater than 75%, no significant differences were found in plaque components or medial area between patients with (11 patients) and without (7 patients) myocardial infarcts at necropsy.

Aged↗

Quantitative analysis of amounts of coronary arterial narrowing in cocaine addicts.

From January 1979 to February 1989, 22 cocaine addicts were studied at necropsy. The 22 patients were divided into 2 groups: death associated with increased cocaine levels at necropsy (13 patients, aged 23 to 45 years [mean 32], and mean total blood cocaine level, 0.36 mg/dl) and noncocaine-related death (9 patients, aged 15 to 50 years [mean 32]). Of the 22 patients, 17 were men and 5 were women; 19 were black and 3 were white. Gross examination in the 22 patients disclosed that 8 patients (36%) had 1 or more of the 4 major (left main, left anterior descending, left circumflex, and right) coronary arteries narrowed at some point greater than 75% in cross-sectional area by atherosclerotic plaque. In 17 cases, the 4 major epicardial coronary arteries were divided into 805 five-mm long segments and a histologic section was prepared from each segment: of the 12 patients with a cocaine-related death, 41 (8%) of 544 five-mm coronary segments were narrowed 76 to 100% and 106 segments (19%) were narrowed 51 to 75% in cross-sectional area by plaque. Of the 5 cocaine addicts who did not die from cocaine overdose, 8 (3%) of 261 five-mm coronary segments were narrowed 76 to 100% and 19 segments (7%) were narrowed 51 to 75% in cross-sectional area by plaque. The frequency of coronary artery disease was greater in patients dying with cocaine in their blood at necropsy compared to those whose death was not cocaine related.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Nursing in Iran.

Explore the source record for details and available documents.

Humans↗