Biomedical subjects

A Reginato

Publications and source records attributed to A Reginato.

At least 19 recordsLinked to original sources

PubMed1999

Refinement of the chromosome 5p locus for familial calcium pyrophosphate dihydrate deposition disease.

Familial calcium pyrophosphate dihydrate deposition disease (CPPDD) is a disease of articular cartilage that is radiographically characterized by chondrocalcinosis due to the deposition of calcium-containing crystals in affected joints. We have documented the disease in an Argentinean kindred of northern Italian ancestry and in a French kindred from the Alsace region. Both families presented with a common phenotype including early age at onset and deposition of crystals of calcium pyrophosphate dihydrate in a similar pattern of affected joints. Affected family members were karyotypically normal. Linkage to the short arm of chromosome 5 was observed, consistent with a previous report of linkage of the CPPDD phenotype in a large British kindred to the 5p15 region. However, recombinants in the Argentinean kindred have enabled us to designate a region<1 cM in length between the markers D5S416 and D5S2114 as the CPPDD locus.

Calcium Pyrophosphate↗

PubMed1996

Clinical assessment of the 1987 American College of Rheumatology criteria for rheumatoid arthritis.

The 1987 American College of Rheumatology (ACR) criteria for the classification of rheumatoid arthritis (RA) were clinically assessed. These criteria do not include findings of synovial fluid (SF) analysis and require no exclusion criteria. We have studied sequential patients with arthritis seen in four rheumatology centers in the Philadelphia area. Classifications by the ACR criteria were compared with our clinical diagnoses. Two hundred ninety eight patients were evaluated, 113 with RA and 185 with other diagnoses. Classifications as RA by the ACR criteria corresponded to our clinical diagnosis in 95% of the cases, corroborating the high sensitivity previously reported. However, we found a lower specificity (73%) than that reported (89%). False positive classifications as RA were found in 71% of patients with psoriatic arthritis, 48% of patients with SLE, and 31% of patients with gout. The specificity could be improved to 89% by excluding disorders with obvious distinguishing extraarticular features such as psoriasis or by SF findings of monosodium urate crystals. Awareness of these possible sources of confusion will further increase the teaching and epidemiologic value of these useful simplified criteria.

Adult↗

PubMed1993

Spondyloepiphyseal dysplasia and precocious osteoarthritis in a family with an Arg75-->Cys mutation in the procollagen type II gene (COL2A1).

Direct sequencing of polymerase chain reaction (PCR)-amplified genomic DNA from a patient with spondyloepiphyseal dysplasia and precocious osteoarthritis revealed a single-base change in exon 11 of the type II procollagen gene (COL2A1), which produces an Arg-->Cys mutation in one allele. The proband is a member of a large Chilean kindred presenting with chondrodysplasia of the hips, knees, shoulders, elbows, and spine associated with severe, early-onset osteoarthritis. All affected individuals exhibit mildly short stature; in addition, five out of seven affected family members display shortened metacarpals or metatarsals. DNA from affected and unaffected family members was PCR-amplified and analysis of restriction digests of the products determined that the mutation segregated with the disease with a lod score of 2.2 at zero recombination. The mutation, which resides in the triple-helical region of type II procollagen at amino acid position 75, is the second example of an Arg-->Cys mutation in the COL2A1 gene in heritable cartilaginous disease and is the first example of a point mutation in the amino terminal region of the alpha 1(II) chain, that results in a spondyloepiphyseal dysplastic phenotype.

Adolescent↗

PubMed1989

Pentose phosphate shunt metabolism by cells of the chick growth cartilage.

We have measured the activity of the pentose shunt pathway in the chick growth cartilage. Measurement of D-[1-14C] glucose and D-[6-14C] glucose metabolism by chondrocytes indicated that pentose phosphate shunt activity was low. However, when the cells were stimulated with phenazine methosulfate (PMS) and t-butyl hydroperoxide, a significant elevation in shunt activity was observed. This activity was further increased by dithiothreitol. Enzymatic and substrate requirements of the shunt pathway were examined and related to morphology of the tissue. It was found that as chondrocytes mature, there is increased glucose-6-phosphate dehydrogenase activity, and decreased quantities of glucose-6-phosphate and NADPH. While these investigations indicated that shunt activity was maximum in hypertrophic cartilage, the results of cytochemical studies suggested that the activity was greatest in those cells that were most removed from the O2 supply. Experiments were performed to examine O2 requirements of chondrocytes in relationship to the pentose phosphate shunt. First, using a phosphorescence quenching technique, total O2 uptake by these cells was found to be constant over a large part of the physiological range of O2 tensions. Over the same range, when stimulated by PMS, O2 uptake by CN- treated cells was increased. In the 1-5 microM O2 range, non-mitochondrial O2 consumption decreased more slowly than total respiration. Finally, the observation that NADPH directly stimulated chondrocyte O2 consumption suggest that cartilage cells may be able to form O2 metabolites.

Animals↗

PubMed1988

Inflammation after blood injection into a synovial-like space is a result of the cellular component rather than the plasma.

The rat subcutaneous air pouch, a model for a synovial-like space, has been used to study the effect of blood as an inducer of inflammation. Six-day-old pouches were injected with autologous whole blood, with plasma or with blood cell pellets. We found significantly more inflammation and proliferation of pouch lining in pouches injected with whole blood or with the blood cell pellets than with the plasma. After the injection of blood or the cell component, large numbers of hemoglobin crystals and lipid droplets were found in the pouch fluid and were associated with erosions of the pouch membrane.

Animals↗

PubMed1982

Crystal-induced arthritis.

The identification of monosodium urate crystals in joint effusions of patients with gouty arthritis established that crystals can cause arthritis. Other crystals causing arthritis have also been identified, including calcium, pyrophosphate dihydrate (chondrocalcinosis, pseudo-gout), calcium hydroxapatite crystals (calcific periarthritis, acute arthritis) and depot corticosteroid crystals (which occasionally cause arthritis when injected intra-articularly.) Crystal-induced arthritis is characterized by acute articular inflammation although rarely causing joint destruction or permanent disability. It is important for clinicians because it can mimic more serious joint diseases like septic arthritis or even rheumatoid arthritis. It can be diagnosed with precision and in some types as in gout can be treated effectively. Also, it constitutes one of the best understood articular inflammatory processes and often is the first clinical clue for the presence of curable metabolic or endocrine diseases.

Adrenal Cortex Hormones↗

PubMed1980