Reconstruction of the anterior face of the base of the skull using coral grafts

Following experimental investigations on animals, small coral grafts have been utilized on patients since 1985 to fill in burr holes (42 patients). This first clinical experimental step has been satisfactory. Therefore, blocks of corals have since then been used as bone graft substitutes for anterior skull basis reconstruction (12 patients). Cheap and easily sterilized, coral implants have the advantage of being inert (99% of calcium carbonate), biodegradable and well reossified. They shorten surgical procedures by avoiding the use of iliac and/or costal grafts. No infectious complications have been noted.     

Influence of pancreas transplantation on cardiorespiratory reflexes, nerve conduction, and mortality in diabetes mellitus

Cardiorespiratory reflexes (CRR) were studied by measuring heart-rate variation during 6 breaths/min respiration and a Valsalva maneuver in 232 insulin-dependent diabetic subjects. Abnormalities were found in 175 patients. During a 7-yr follow-up, 41 (23.4%) patients with abnormal and 2 (3.5%) with normal CRR tests died. The mortality rates of diabetic patients with abnormal autonomic function tests were 17% at 2.5 yr, 33% at 5 yr, and 40% at 7 yr, significantly higher (P less than 0.002) than in patients with normal tests (rates of 4.6, 4.6, and 13.8% at the respective intervals). Nerve conduction studies (NCS) were indicative of somatic neuropathy in 148 of 205 patients. Mortality rates were higher in patients with abnormal NCS than in those with normal results (P less than 0.025). Among patients with abnormal autonomic function, patients with a functioning pancreas transplantation (PTx) had better survival rates than patients with a failed PTx (P less than 0.005) and, on long-term follow-up, better rates than patients without PTx. Similar results were found comparing the same group of patients who had abnormal NCS.     

Effects of an anti-interleuktn-6 (IL-6) murine monoclonal antibody in a patient with acute monoblastic leukemia

Because IL-6 has been involved in the pathogenesis of acute monoblastic leukemia, we investigated thein vitro anti-proliferative effect and thein vivo anti-tumoral effect of an anti-IL-6 murine monoclonal antibody (mAb) in a patient with MSB type acute leukemia. In the current study, we clearly show the IL-6 dependence of monoblastic cell viability and proliferationin vitro in short-term cultures of malignant cells and the clinical activity of the anti-IL-6 murine mAb. The complete neutralization of IL-6in vivo was associated with a transient but complete disappearance of malignant monoblastic cells in the peripheral blood, with improvement or even normalization of several other biological parameters of disease activity, No immunization against the anti-IL-6 murine mAb was observed.     

Penetration of Schistosoma japonicum cercaria into host skin.

The anterior part of Schistosoma japonicum cercaria is a specialized head organ which can slightly stretch out and retract. There are three different types of large unicellular glands in cercarial body, consisting of one head gland, 2 pairs of pre- and 3 pairs of postacetabular glands. These glands differ in position, gross feature, histochemistry and functions. Both polysaccharase and protease activities are demonstrated in the secretions from these glands. Mode of cercarial penetration is described in detail and the penetration is effected by a combination of lytic secretions and mechanical movements. The schematic representation of the process of cercarial penetration is presented. The dynamic distributions of schistosomula in skin at different time intervals after skin penetration in various mammalian hosts are shown. Some newly transformed schistosomula die while penetrating into the skin of 7 mammalian species and the mortality rate varies with the host species, and that can also be affected by the age of cercariae following emergence from the snail. Some physiological aspects between cercariae and newly transformed schistosomula are compared. In contrast to cercariae, schistosomula are saline-adapted and water-intolerant. They were modified histochemically and antigenically.

     

Preservation of human corneas in organ culture: technical protocol

Using organ-culture preservation human corneas were preserved up to 5 weeks in a modified tissue culture medium at 37 degrees C. The endothelial viability was examined after staining with trypan-blue 0.3%, after determination of endothelial cell density and cell loss and by light microscopy after staining with trypan-blue 0.3% and alizarin red 1%. The biochemical analysis of the medium (pH, glucose, lactate) has allowed the evaluation of three kinds of storage. The influence of time preservation on the endothelial viability and the metabolic conditions are determined. At the end of this study a clinical trial is proposed.     

Purification and chemical modification of porcine bone morphogenetic protein

Implantation of porcine bone morphogenetic protein (pBMP) in the muscle induces differentiation of mesenchymal-type cells and results in endochondral bone formation. pBMP was isolated from porcine demineralized bone matrix and purified by hydroxyapatite chromatography, Sephadex G75 gel filtration, preparative sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), preparative isoelectric focusing (IEF), and chromatofocusing fast protein liquid chromatography (FPLC). Porcine BMP has an MW of 26 K and a range of pI from 4.65 to 4.73 determined by SDS-PAGE and IEF, respectively. Reconstitution with the citrate buffer supernatant fraction enables as little as 50 micrograms of the soluble pBMP fractions to induce osteogenesis in an in vivo assay. Chemical modification studies indicate that the osteoinductive potential of the pBMP molecule depends on tyrosine, carboxyl groups, and disulfide bonds and can be increased by modification of sulfhydryl groups. Modification of arginine and tryptophan has no effect on bioactivity. By pepsin-limited proteolysis, fragments of pBMP with an MW of 6-14 K show definite, although reduced, BMP activity.     

Microvascular corrosion casting of normal tissue, transitional mucosa and adenocarcinoma in the human colon.

The microcirculatory architecture of normal tissue, transitional mucosa and adenocarcinoma of the human colon was investigated with microvascular corrosion casting (MVCC) combined with scanning electron microscopy (SEM). The study showed that the capillaries within the normal mucosa were arranged in a regular hexagonal pattern around the mucosal glands and that the microvessels of transitional mucosa mostly had lost the typical hexagonal pattern and become slightly wider in diameter. The microvessels in the tumor periphery were increased in number and disorganized, and presented large variation in morphology with claw-like formations, widened sinuses, diverticula and appendixoid patterns. Microvessels were lacking in the central areas of tumors. These morphological alterations may serve as additional indicators of tumor development.