Biomedical subjects

S Santavirta

Publications and source records attributed to S Santavirta.

At least 19 recordsLinked to original sources

PubMed1992

Synovial sarcoma. A clinicopathological study of 31 cases.

Thirty-one surgically treated cases of synovial sarcoma were reviewed. The mean age of the patients at primary surgery was 37 years (range 10-78 years). Twenty-nine of the tumors were of the biphasic type and two were monophasic. Currently a monophasic synovial sarcoma can be considered as a specific entity. In contrast to other soft-tissue sarcomas, synovial sarcomas present the characteristics of a carcinosarcoma. The 5-year survival rate in this study was 55% and the 6-year survival rate 50%; after 6 years there were no recurrences. The primary treatment should follow the same guidelines that are currently given for other soft-tissue sarcomas: wide and radical excisional margins should be aimed at. Excisional treatment even of repeated pulmonary recurrences may be rewarding.

Adolescent↗

PubMed1992

Inflammation of the subacromial bursa in chronic shoulder pain.

Subacromial bursal tissue was studied in 12 patients operated on for painful (10 patients with constant pain and 2 patients with pain on motion) rotator cuff tendinitis/impingement syndrome. The Neer acromioplasty technique was used. Six patients had moderate inflammatory changes and one had a slight inflammation. In three of the five remaining patients, the subacromial bursa did not show any signs of inflammatory involvement, but patients experienced pain at rest and at night, reflecting clinical inflammation in tissues other than the bursa. The two patients with pain only on strain did not show inflammation of the bursa. Immunohistochemical typing of the bursal tissue disclosed a typical chronic mononuclear cell infiltrate consisting mainly of CD2-positive T lymphocytes (50-80% of all inflammatory cells), accompanied by less frequent CD11b (C3bi receptor)-positive monocyte/macrophages (10-40%). The relative paucity of plasmablasts/plasma cells expressing PCA-1 suggests this to be an inflammatory rather than an immune response. Active involvement of some of the local cells is suggested to be the source of algogenic and hyperalgesic substances contributing to pain in chronic shoulder pain syndromes.

Acromion↗

PubMed1992

Immunoreactive neuropeptide nerves in ligamentous tissue in chronic shoulder pain.

Coracoacromial ligament and periligamentous fatty and loose connective tissue obtained during Neer's acromioplasty in patients with chronic painful rotator cuff tendinitis/impingement syndrome was studied for possible signs of inflammatory involvement and for the presence of neuropeptide-containing nerves, using routine histology and immunoperoxidase staining. No accumulations of inflammatory cells were found in the tissues studied. The dense ligamentous tissue proper was practically aneural, as was seen in staining for the generalized neuronal markers protein gene product 9.5 and synaptophysin. In contrast, the periligamentous fatty and loose connective tissue was innervated. Almost all nerves in such tissue contained C-flanking peptide of neuropeptide Y, whereas substance P, calcitonin gene-related peptide, and vasoactive intestinal peptide-containing nerves were not found at all or were extremely rare. This suggests that the coracoacromial ligament is not a target of irritative inflammation. In the periligamentary sheath, nerves containing markers for the C-type nociceptive pain fibers were practically absent and all local nerves were postganglionic sympathetic vaso-regulatory nerves.

Adult↗

PubMed1992

Granzyme A-immunoreactive cells in synovial fluid in reactive and rheumatoid arthritis.

Perforin and granzyme A co-localize in the cytotoxic granules of killer cells like cytotoxic T lymphocytes (CTL). Perforin is the cytolytic pore-forming protein, whereas the function of the homodimeric serine protease granzyme A and other members of the granzyme family is still unclear. Granzyme A-immunoreactive cells formed 8 +/- 2% of the resting peripheral blood lymphocytes of healthy individuals. In contrast, granzyme A-positive cells formed 15% of peripheral blood mononuclear cells in patients with reactive or rheumatoid arthritis. However, 29 +/- 4% (p < 0.05 compared to normal peripheral blood) and 25 +/- 4% (p < 0.05) of all lymphocytes in synovial fluid in reactive and rheumatoid arthritis, respectively, were granzyme A-positive. This suggests involvement of cell-mediated cytolytic mechanisms in the articular pathogenic mechanisms. This involvement, however, does not differentiate between reactive and rheumatoid arthritis.

Adult↗

PubMed1992

Collagenase in synovitis of rheumatoid arthritis.

There are two types of collagenases, products of two distinct genes, called MMP-1 (matrix metalloproteinase 1 or "fibroblast-type collagenase") and MMP-8 ("neutrophil collagenase"). In synovial fluid, MMP-8 is stored as latent proenzyme in polymorphonuclear neutrophils. MMP-8 is activated by hypochlorous acid produced by myeloperoxidase from hydrogen peroxide and chloride ion and by the hydroxyl radical produced in Haber Weiss reaction fed by superoxide produced by, eg, NADPH (reduced nicotinamide adenine dinucleotide) oxidase and xanthine oxidase. In addition to activation upon secretion, oxidatively modified MMP-8 is susceptible to a subsequent proteolytic attack and activation by cathepsin G. The authors suggest that activation of neutrophil-derived MMP-8 involves oxidative, nonproteolytic activation upon secretion and a more slowly progressive proteolytic activation by cathepsin G (or chymases and tryptases), and that these oxidative and proteolytic activation mechanisms act in concert. In contrast to MMP-8, MMP-1 is synthesized de novo and secreted immediately after synthesis by fibroblasts, macrophages, and some epithelial cells. Human rheumatoid synovial tissue contains mainly fibroblast-type MMP-1 collagenase as assessed by collagenase extracted from synovial tissue and by MMP-1 and MMP-8 immunostaining. It is suggested that in vivo, MMP-1 in synovitis tissue is activated by a plasminogen activator/plasminogen/prostromelysin (alternatively tryptases)/proMMP-1 cascade. In conclusion, MMP-8 and MMP-1 show type-specific compartmentalization and modes of activation in rheumatoid synovial fluid and tissue.

Arthritis, Rheumatoid↗

PubMed1992

Porous-coated anatomic (PCA) knee arthroplasty. 3-year results.

During 1984-1986, the authors used the PCA total knee replacement system on 92 knees in 86 patients who were followed for an average of 3.2 years (range, 2.2-4.5 years). Of the 92 knees, 42 were treated due to rheumatoid arthritis (RA) and 50 due to primary or secondary osteoarthrosis (OA). The average age of the patients was 60 years (range, 32-78 years). Seventy-one of the 92 prostheses were inserted without the use of methyl methacrylate cement. Fixation screws for the tibial plate were used in eight cases. One knee was revised due to ligamentous laxity by inserting a thicker tibia plate. Radiographically, there was radiolucency of more than 2 mm below two tibial plates (both RA), and four patellar components (2 RA, 2 OA; 4.3% of total) showed a radiolucent zone of 1 mm or more. Clinically, there were no evident loosenings. According to the Weinfeld scale, 80 knees (37 RA, 43 OA; P = NS) had an excellent result, 10 (6 OA, 4 RA) good, and 2 (1 OA, 1 RA) satisfactory. In comparison, the Hungerford scale gave 47 excellent, 30 good, 14 satisfactory, and 1 poor result. These results reflect that cementless PCA total knee replacement also appears to provide good fixation in both OA and RA knees.

Adult↗

PubMed1992

Ruptures of the heart in seatbelt wearers.

We analyzed the records of 4,169 victims of traffic collisions fatally injured during the period 1972 to 1985. Chest injuries were recorded as the main cause of death in 1,121 victims; 207 of them had worn a seatbelt. Rupture of the heart was found at autopsy in 75 of these seatbelt wearers. Exact information on the location and the size of the heart rupture was available in 47 cases. For a control group, we analyzed 47 randomly chosen unbelted victims who had sustained a fatal heart rupture in comparable collisions. The site of cardiac injury was a ventricle in 75.5%. In frontal impact collisions the mechanism leading to heart rupture is usually crushing against the steering wheel, even in seatbelt wearers. Most of the victims had multiple injuries, and only serious collisions, often with a heavier vehicle, led to fatal heart rupture.

Accidents, Traffic↗

PubMed1992

Relationship between neuropeptide immunoreactive nerves and inflammatory cells in adjuvant arthritic rats.

The purpose of this study was to assess the relationship of neuropeptide nerves and inflammatory leukocytes in PVG rats with adjuvant-induced arthritis. Substance P- and calcitonin gene-related peptide (CGRP)-immunoreactive nerves and inflammatory leukocytes were studied, using peroxidase (ABC) and/or alkaline phosphatase (APAAP) staining. Inflamed synovial tissue proper was infiltrated with neutrophils, ED1 macrophages and focal accumulations of CD2 T lymphocytes. In such tissue, the relationship between peptide-immunoreactive nerves and inflammatory cells was such that substance P and CGRP nerves were absent in heavily infiltrated villous synovial tissue, whereas healthy synovial tissue and non-inflammatory areas in adjuvant arthritic rats were innervated by substance P and CGRP nerves close to normal synovial tissue resident cells. In order to elucidate an eventual mechanism for lost immunoreactivity, healthy synovial tissue was exposed to chymotrypsin or oxygen derived free radicals (ODFR) in vitro. The former treatment caused total loss of immunoreactivity. These findings suggest that neuropeptides and neuropeptide containing nerves may be destroyed by locally produced proteolytic enzymes and various reactive oxygen species in the vicinity of inflammatory cells.

Animals↗

PubMed1992

Determinants of osteoporotic thoracic vertebral fracture. Screening of 57,000 Finnish women and men.

A population sample of 27,000 Finnish women and 30,000 men was studied for the presence of a thoracic vertebral fracture. In both sexes, the prevalence of such fractures increased with age: after 40 years of age in the men and after 55 years of age in the women. The interaction of sex and age was significant, and even when the other determinants were adjusted for. In the women aged 35-44, 55-64, and 75 years or more, the prevalence per 1,000 was respectively 2.4, 5.1, and 29, and in the men in the corresponding age groups 5.2, 15, and 28. A previous history of trauma was a fracture determinant in both sexes. In the men, but not in the women, there was an increased risk of fracture when there was a history of tuberculosis and/or peptic ulcer, and in current smokers. Thus, contrary to observations on extremity fractures, the men had an increased risk of sustaining a thoracic vertebral fracture compared with the women. This may reflect differences in the development of osteoporosis in the axial skeleton versus the appendicular skeleton.

Adult↗

PubMed1992

Cemented versus cementless hip arthroplasty. A review of prosthetic biocompatibility.

The fibrous interface tissue between hip prostheses and surrounding bone is often morphologically and functionally synovial-like. The fibroblast is the major cell type; but also giant cells and macrophages are present, and their numbers are increased in the occasional adverse-type host reaction to the prosthesis. Adverse lytic reactions are often associated with methylmethacrylate debris, whereas in cementless cases, polyethylene and metallic (titanium) wear debris seem to cause adverse reactions. Osteoblasts, osteoclasts, and mesenchymal collagenase secreted by fibroblasts and macrophages play an important role in the process of prosthetic loosening. Methylmethacrylate is immunologically relatively inert, while it induces inflammatory mononuclear-cell migration. Both cemented and cementless prostheses cause a foreign-body type host response, including adaptive and reactive processes. This response includes the formation of fibroblast-like B-type lining cells, which are able to synthesize and secrete hyaluronate. Material surfaces of hip arthroplasty components also provide a unique environmental niche to which staphylococcal strains adhere and colonize. Antibiotic resistance is related to the material colonized rather than to the presence of an exopolysaccharide barrier; organisms bound to polyethylene and methylmethacrylate are more resistant than organisms that are bound to stainless steel. An understanding of prosthetic biocompatibility requires an appreciation of tissue cell, bacterial cell and host defense-system response to biomaterials. The site of implantation is a stage on which the "players" (bacteria, host cells, and organic moieties) interact and compete, and before which the host is a "responsive audience."

Anti-Bacterial Agents↗

PubMed1992

Distribution of nerve endings and sensory neuropeptides in rat synovium, meniscus and bone.

The nervous system collects information from the outer world by specific senses and from the interior milieu by somatic senses. This information is processed and stored in memory and affects various bodily functions through the efferent arm of the nervous system. The efferent chemical neuropeptide message is transported intra-axonally to the site of action, which imparts site-specificity to the peripheral, paracrine neuropeptide effects. In the present study, immunohistochemistry using the immunoperoxidase method with nickel amplification was applied to visualize the topographical distribution of articular nerve fibres and nerve endings using the markers PGP 9.5 and synaptophysin, respectively. Furthermore, to get a comprehensive idea of the sensory innervation of the articular and para-articular tissue, antisera to calcitonin gene-related peptide (CGRP) and substance P were employed. Samples were collected after fixation by perfusion followed by immersion in fixative and decalcification by a special method, which also allows studies of the bone innervation. PGP 9.5- and synaptophysin-immunoreactive type IVa and IVb nerve fibres and endings were found in the synovial lining and sublining tissue and in the vascularized peripheral parts of the menisci. Furthermore, periosteum, bone marrow and the epiphyseal growth plates were also innervated, whereas innervation of the diaphyseal and metaphyseal bone was more sparse. PGP 9.5- and synaptophysin-immunoreactive nerves were also characterized by their CRGP, and to some extent, substance P content. Because of their distribution, the peripheral peptide-containing type IVa and IVb nerve fibres and nerve endings are in a position to participate in the pathogenesis of arthritis, including aspects of nociception, tissue remodelling and neurogenic inflammation.

Animals↗

PubMed1992

Innervation of bone from healthy and arthritic rats by substance P and calcitonin gene related peptide containing sensory fibers.

Mechanical stress causes remodelling of bone, a transformation of bone structure by physical forces through an unknown mechanism. Inflammation also affects bone structure, through altered use and the production of various inflammatory mediators. The peripheral nervous system may play both a sensory and an efferent role in the mechanical and inflammatory influences on bone structure. We studied the occurrence of substance P and calcitonin gene related peptide (CGRP) containing nerves in periosteal tissue, bone marrow, diaphysis and epiphysis of the ankle and knee joints of healthy and adjuvant arthritic rats. In arthritic animals, only ankle joints were affected by the inflammation. The periosteum was richly innervated both in healthy and arthritic animals. In arthritic rats few nerve fibers penetrated the woven, callous bone underlying the periosteum. Also bone marrow contained substance P and CGRP immunoreactive nerves in normal bone, whereas the hypercellular bone marrow of arthritic rats showed a decrease in the density of substance P and CGRP containing fibers. Epiphysis had a dense innervation compared to diaphysis. In contrast to large erosions, small peripheral erosions contained some CGRP immunoreactive fibers, perhaps as a sign of attempts of reactive repair. Our results suggest a local delivery system of potent peptide regulatory factors in bone, a system also affected by the pathophysiology of arthritis.

Animals↗

PubMed1992

The relation of extraarticular tenderness to inflammatory joint disease and personality in patients with rheumatoid arthritis.

We measured the pain tenderness threshold at 16 fibrositic tender points in 44 consecutive patients with rheumatoid arthritis (RA) attending the outpatient rheumatology clinic of a university hospital. Pressure threshold measurements were transformed to z units to equalize the weights of the values at different anatomic sites and were then summed. This pain tenderness score correlated with the joint score index (p less than 0.02, r = -0.363), signifying a low pain threshold in the patients with a high joint score index. In contrast to this, the pain tenderness score was not explained by either personality factors or the generalized disease activity measuring variables (erythrocyte sedimentation rate, C-reactive protein). Our results show that the fibrositic point tenderness is real in RA, and that the tenderness is augmented near the active joints. The pain tenderness score of patients with RA is not affected by the subject's personality but may relate to sensitization of the pain fibers in arthritic joints.

Adult↗

PubMed1992

Hip fractures in urban population in Finland.

We studied prospectively the occurrence of hip fractures among the over 49-year-old urban populations (n = 88,206) in the cities Tampere, Jyväskylä and Kotka in 1989 and compared the results with a parallel Scandinavian multicentre study. During 1989, there were 266 inhabitants who were treated for a hip fracture, 213 of them were women. Women had in 132 cases a femoral neck fracture and in 81 cases a trochanteric fracture, and the corresponding numbers for men were 22 and 31. Among women, the total hip fracture incidence in Jyväskylä (n = 22) was the lowest when compared with the ones in Tampere (n = 47) and Kotka (n = 36). These incidences were on average lower than in the other Scandinavian cities studied in parallel. The all over ratio of femoral neck/trochanteric fractures was 1.1 in Tampere, 3.0 in Jyväskylä and 2.2 in Kotka and in Tampere, women had 9.3 times more femoral neck fractures than men. Our study showed that in Finland in three major cities the hip fracture incidence was lower than what has been similarly registered in corresponding urban populations in other Scandinavian countries. We also point out that the relative part of trochanteric fractures appears to be increasing.

Aged↗

PubMed1992

Immunologic studies of nonunited fractures.

We studied tissue samples of noninfected delayed union or nonunion of diaphyseal bones in 10 patients immunopathologically and neuroimmunologically 4 to 25 months after the primary injury. Samples mostly consisted of vascularized connective tissue of varying density with the proline-4-hydroxylase-containing fibroblast as the major cell type. Most inflammatory cells were CD4 T-lymphocytes and their number was always twice that of the CD8 positive cells. Staining for CD11b positive monocyte/macrophages showed in all samples positive cells scattered in the connective tissue stroma with perivascular enrichments. Mast cells were absent or very rare. Our findings suggest that delayed union and nonunion tissue consists of vascularized connective tissue, which mostly contains 5B5 fibroblasts, CD11b macrophages and vascular endothelial cells with only few immigrant recently recruited monocytes or lymphoid cells. Almost all resident cells seem to be involved in tissue remodeling as suggested by their content of fibroblast-type MMP-1 and its proteolytic activator MMP-3 or stromelysin. The most striking finding was the paucity or total lack of peripheral innervation, which may have to do with the nonunion of the fracture.

Adolescent↗

PubMed1992

Hip fractures in two health care regions in Finland in 1989: an analysis of treatment.

We studied prospectively the demographic data, fracture types and modes of treatment in 390 patients with acute traumatic hip fractures in two health care regions in Finland, the Middle Finland region and the Kymenlaakso region in 1989. In Middle Finland population (251,203 inhabitants) 199 patients with a hip fracture were admitted to two acute care hospitals, while 191 patients were admitted in Kymenlaakso (population 189,726) to four acute hospitals. There were no significant differences in the sex- and age-specific incidences between the two regions. In Middle Finland, 70% of the fractures were of the femoral neck, 28% were trochanteric and 2% subtrochanteric. The corresponding figures in Kymenlaakso were 57%, 38% and 5% (P < 0.05). In Middle Finland, 73% of the femoral neck fractures were treated primarily with a hemiendoprosthesis, 2% with primary total hip replacement and 25% by osteosynthesis. The corresponding figures in Kymenlaakso were 81%, 7% and 12% (P < 0.001). The mean duration of hospital stay was 14 days in Middle Finland and 21 days in Kymenlaakso (P < 0.01).

Adult↗

PubMed1991

Proliferative cell response to loosening of total hip replacements: a cytofluorographic cell cycle analysis.

Monocyte/macrophages and fibroblasts are the major reactive cells in the periprosthetic connective tissue in a loose totally replaced hip. Monocyte/macrophages are bone-marrow-derived, hematogenous cells, whereas mesenchymal fibroblasts replenish by local proliferation. The cell-cycle-phase frequency distribution therefore reflects the local mitotic fibroblast response to the loose total hip replacement (THR) implant. In 13 patients who underwent revision of a loose THR implant, most of the local cells were in the resting G0/G1 phase (88.1 +/- 6.3%, mean +/- SD), whereas 8.6 +/- 3.7% were in the S phase of the cycle, and 3.4 +/- 2.9% had already reached the G2/M phase. The highest DNA values were recorded in an osteoarthritic patient undergoing revision 4 years after the primary uncemented THR, while the lowest values were observed in a rheumatoid arthritis patient with a loose cemented prosthesis 15 years after the primary operation. The results suggest that the local proliferative fibroblast response in general is uniform and does not seem to depend on the type of prosthesis or the use of cement. The responses in aggressive granulomatous-type loosening and the common type of loosening were similar.

Aged↗

PubMed1991

Biocompatibility of hydroxyapatite-coated hip prostheses.

In three patients a mechanically well-fixed Mathys Ceros 80 (Ha) hydroxyapatite-coated acetabular component was revised 2, 5 and 13 months after total hip replacement due to component malposition. In each case there was a thin cellular connective tissue membrane between hydroxyapatite and bone, the main cell type being fibroblast with only occasional giant cells. Immunohistological analysis revealed some MHC locus II antigen positive cells that were identified as monocytes. No interleukin-2 receptor positive cells were found. Under clinical cyclic loading conditions there does not seem to be chemical fixation or bony ingrowth into the hydroxyapatite coated prosthesis component. In human lymphocyte cultures, hydroxyapatite (Interpore 200, particle diameters 15-40 microns) did not cause an increase in lymphocyte DNA synthesis as assessed by the 3H-thymidine incorporation method on culture days 1, 3 and 5. As analysed with lymphocyte activation markers, the hydroxyapatite-dependent expression of MHC locus II antigen was modest and differed significantly (P less than 0.05) from that in culture medium only on day 3. Hydroxyapatite induced only a slight interleukin-2 receptor expression that did not differ from culture medium on days 1, 3 and 5. CD4 and CD8 positive lymphocytes as well as monocytes were not seen attached to hydroxyapatite particles during the culture days. Our findings suggest that hydroxyapatite is an immunologically inert implant material.

Acetabulum↗