Biomedical subjects
Publications and source records attributed to M Zakaria.
The authors report their own experience with completely implantable systems for the long-term chemotherapeutic treatment, compared with a review of modern literature. The experience even if low demonstrates a good methodology in reducing the number of complications associated with the use of percutaneous catheters.
The effects of thyrotropin-releasing hormone (TRH) on hemodynamic variables, oxygen delivery (DO2), and oxygen consumption (VO2) variables in canine hemorrhagic shock were studied. Anesthetized adult dogs were bled over 30 min to a mean arterial pressure (MAP) of 50 mm Hg. Shock was maintained at this level for half an hour. The animals were divided alternatively into two groups. In the first group (n = 5) a bolus of TRH (2 mg/kg) was given intravenously. The second group (n = 5) served as control and received equal amounts of D5W. Blood samples were obtained regularly up to 120 minutes after TRH or placebo. Differences in the two groups were statistically tested. After TRH, MAP pressure, cardiac output, and systemic vascular resistance increased significantly. DO2 improved after TRH but VO2 remained unchanged. In all dogs, sequential beta endorphin level were measured and were shown to rise after induction of shock. This data indicates that TRH may be of therapeutic benefit in the treatment of hemorrhagic shock and that beta endorphin may be an important pathophysiologic factor.
Normalization of hemodynamic, oxygen transport and oxygen consumption indices occurred within a week of treatment in a patient with myxedema coma. Ventilatory weaning and extubation was achieved using aminophylline, physical therapy and pleural drainage. Before extubation, naloxone was administered without any significant ventilatory improvement or change in endorphin levels.
Explore the source record for details and available documents.
A poxvirus was isolated from skin lesions on the tail of a rat (Rattus norvegicus) in Kuwait in February, 1982. The virus grew on the chorioallantoic membrane (CAM) developing chicken embryos and induced small generalized haemorrhagic pock lesions, 72 hours post-inoculation. It grew also with cytopathic effect (CPE) in CER and Vero cell lines. In cultured cells it produced cell rounding and syncytia 48-72 hours post-infection. The virus was resistant to the effect of ether as well as to chloroform, and showed haemagglutinating activity against chicken red blood cells in a low titer (1:16). It induced in the rabbit skin nodular lesions 4-5 days post-infection. Electron microscopy of the negatively stained preparations revealed brick-shaped typical poxvirus virions measuring 220-250 millmicron in diameter. By using vaccinia antiserum the virus antigen was precipitated in the agargel immunodiffusion test and this indicates its relation to the genus Orthopoxvirus.
Aberrations in the metabolic pathways of catecholamines in patients with neural crest tumors result in characteristic urinary excretion patterns of their catabolites. Tumors such as pheochromocytoma, neuroblastoma and ganglioneuroma usually defy clinical diagnosis because of their rarity, small size, intraabdominal position and clinical symptoms similar to those of essential hypertension. Quantitative determination of catecholamine metabolites such as vanillylmandelic acid (VMA) and 3-methoxy-4-hydroxyphenylethyleneglycol (MHPG) offers possibilities for reliable confirmation of diagnosis. However, previous techniques for the assessment of catabolite levels suffered from inadequate sensitivity, reproducibility or specificity, which seriously diminished their usefulness as biochemical determinants in the prognosis of these life-threatening tumors. Reported in this paper is the analysis of urinary levels of VMA and MHPG using reversed-phase high-performance liquid chromatography with electrochemical and sectrophotometric detection. We present the excretion patterns showing these metabolites in 15 control subjects, 15 patients with pheochromocytoma and 5 patients with neuroblastoma.
The usual methods for provitamin A evaluation of foods convert the total pigment amount, determined spectrophotometrically, into vitamin A units. Since the totally inactive lycopene is the major carotenoid in the tomato, such readings result in erroneously high provitamin A values. In view of the recent development of chemically bonded, reversed-phase, microparticulate packings and their use in high-performance liquid chromatography which combines highly accurate and reproducible resolution with the speed and ease of operation, a new method using such a system was developed to isolate carotenoid pigments from tomato samples. A 15-min column separation was thus achieved, dramatically decreasing the analysis time of the classical open column chromatographic procedures, which often result in unresolved and altered fractions due to long-term exposure to oxygen, light, solvents and sometimes adsorbent. beta-Carotene and lycopene were determined and quantitated in six tomato samples. beta-Carotene, 100% vitamin A-active, was expressed in International Units of vitamin A. The newly developed method gives a more reliable evaluation of the fruit potency in vitamin A than the methods of the Association of Official Analytical Chemists currently used for food composition tables.
The authors report their experience of microsurgical reconstructive techniques using musculo-cutaneous free flaps after radical operations for head and neck neoplasms.
The Authors present a case of hypopharyngeal tumor in which digestive continuity was assured by a jejunal autotransplant. Tumoral exeresis and jejunal preparation were carried out at the same time by two surgical teams. The use of microsurgical techniques assures the revascularization of the neck transplant by implementing the superior thyroid artery and the internal jugular vein. Digestive anastomoses complete the operation.
Explore the source record for details and available documents.