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V Fornasier

Publications and source records attributed to V Fornasier.

43 records · Page 3Linked to original sources

Role of viable mycoplasmas in the pathogenesis of arthritis induced by M. pulmonis.

The role of viable M. pulmonis organism in the pathogenesis of both the acute and chronic phases of M. pulmonis-induced arthritis was examined. In the acute phase of the arthritis most clinically involved joints contained organisms and the degree of clinical arthritis in a given joint correlated with the number of organisms isolated. The more severe the acute arthritis, the more frequently the M. pulmonis organism was isolated from the joints during the chronic phase. In the chronic phase, arthritis defined histologically correlated with the presence of M. pulmonis organisms within a given joint. No correlation was observed between clinical arthritis during the chronic phase and histopathology or the presence of M. pulmonis organisms within the joint. In chronically infected mice, M. pulmonis was isolated from the joints only but not from the blood, liver, spleen, lung or kidney of any mouse examined. The results support the concept that viable organisms play an essential role in the pathogenesis of the acute and chronic phases of M. pulmonis-induced arthritis in mice.

Animals↗

Enhanced resistance of mice to Mycoplasma pulmonis-induced arthritis by administration of killed Corynebacterium parvum.

Inoculation of mice with Corynebacterium parvum 14 days before intraperitoneal inoculation of Mycoplasma pulmonis resulted in arthritis of significantly lesser magnitude than in control mice as measured both clinically and histologically. Mycoplasmas were isolated from the joints of mice inoculated with C. parvum less frequently than from control mice when the arthritis was maximal. Mycoplasmas were also isolated in smaller numbers from the blood and joints of mice pretreated with C. parvum within 2 hr after M. pulmonis inoculation. Complement-fixing antibody to M. pulmonis did not account for the differences observed. C. parvum given during an established mycoplasmal infection, although capable of enhancing elimination of M. pulmonis from the joints of infected mice, had no effect upon the arthritis as measured clinically or histologically. The results provide evidence that immunomodulators such as C. parvum are capable of enhancing elimination of mycoplasmas from the joints of infected mice prior to or after the induction of arthritis.

Animals↗

Effect of T-cell deficiency on the chronicity of arthritis induced in mice by Mycoplasma pulmonis.

Mycoplasma pulmonis inoculated parenterally into athymic nude mice congenitally deficient in T cells caused a chronic arthritis of significantly greater magnitude than in immunologically normal mice. During the chronic phase of arthritis, M. pulmonis organisms were isolated from the joints and spleens of athymic nude mice more frequently and in larger numbers than from immunologically normal mice. The results support the concept that impaired T-cell function predisposes the mice to a severe degree of chronic arthritis as a result of their failure to eliminate the causative organisms.

Animals↗

Increased bone mineral content in young adults with familial hypophosphatemic vitamin D refractory rickets.

Seven adults with familial hypophosphatemia have been investigated by histologic and radiographic examination of bone, and estimates of bone mineral status by in vivo neutron activation analysis (IVNAA). Histological examination showed severe osteomalacia and osteosclerosis in all cases. Radiography showed skeletal deformities and other sequelae of severe rickets of childhood in five of the seven cases, with, in addition, thickened well-mineralized bones; the other two showed normal radiographs. IVNAA measurements showed that the first five had greater than normal bone calcium and that the other two had normal values. Thus, in all cases there is a greater than normal total bone tissue (osteoid and mineralized bone together). The quantitative body calcium measurements show clearly that osteosclerosis occurs in familial hypophosphatemia, confirming the opinions based on histological and radiological data. Although there has been occasional reference to this sclerosis in the literature, up to the present it has received little attention.

Adolescent↗

MRI of the cartilaginous epiphysis of the femoral head in the piglet hip after ischemic damage.

MRI of the cartilaginous epiphysis (CE) of piglet femoral head was performed after ischemic damage to study the changes in the CE found on MRI and to correlate these changes with histologic findings. Avascular necrosis of the femoral head was induced with a suture ligature in nine piglets; one piglet was killed postoperatively on day 3 and on weeks 1, 2, 3, 4, 6, 7, and 8 (two piglets were killed on week 3). MRI of the ischemic and contralateral nonischemic hip joints were obtained with a 60-mm field of view (low resolution MRI). Biopsy cores of the femoral heads were imaged with a 15-mm field of view (high resolution MRI) and correlated with histologic sections. The CE for all operated hips, except for the 3-day postoperative specimen, showed evidence of ischemic changes on histologic assessment; the severity of damage increased with time. The MRI appearance of ischemic and nonischemic CE was clearly different by 2 weeks after the operation. No trilaminar signal pattern was evident in the high resolution T2-weighted (T2W) imaging of the ischemic CE from 2 weeks after the operation. In the 3- to 8-week postoperative specimens, focal areas of low signal intensity on high resolution T1-weighted (T1W) and T2W imaging corresponded to the areas of chondronecrosis found on histologic assessment. The regions of high signal intensity on T2W imaging corresponded to the areas of chondrocyte clusters with increased safranin-O staining. High resolution MRI can demonstrate changes in the CE associated with ischemic injury and may have a role in the assessment of the CE and its development after ischemic injury.

Animals↗

Detailed examination of complete bioprosthetic heart valves.

Six (3 control and 3 explanted) bioprostheses were examined histologically after embedding the complete valve in "plastic" and sectioning across the valve at 90 degree to the horizontal plane, and then horizontally across a stent post, with a low speed saw. The prostheses, porcine or pericardial, had been in place 52 to 121 months. In addition to cusp changes of degeneration and calcification that have been previously reported, the authors found extensive pannus deposition on the cloth covering the inflow surface of the prostheses, with some extension onto the biologic components; evidence of insudation of tissue fluid and ingrowth of fibroblasts; deposition of collagen; and infiltration of mononuclear cells in the interstices and interfaces. Non-biologic components showed changes which may have affected prosthesis function. The synthetic material covering the metal/plastic frame showed interstitial mononuclear cells. Two of the three explanted valves showed changes in the polymeric plastic, and one in the metal components, including accentuated notching along the surfaces when compared to unimplanted prostheses. A larger number of prostheses must be examined before definite conclusions can be drawn.

Adult↗

Osteointegrated porous-coated titanium implants.

The study deals with the bone-prosthesis interface using an in vivo experimental animal model in relation to loading and walking on the prosthetized hip, studied by force plate analysis. The interface is studied from a histological and morphometric point of view by means of a LECO 2001 system. Results show that titanium favors osteointegration according to the criteria of Branemark even in conditions of physiological loading; bone ingrowth (that cannot be considered a true process of osteointegration) was 27.6%; furthermore, we quantified two models of periprosthetic bone growth in an osteointegrative sense: total bone bonding (27.4%) and core bone bonding (bone that grows in direct contact with the prosthesis) that was 16.1%. Finally, osteointegration tends to be greater where contact between the bone and the prosthetic is closer, regardless of the type of prosthetic coating.

Animals↗