Minocycline in rheumatoid arthritis.
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Biomedical subjects
Publications and source records attributed to M Pras.
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This report presents refined genetic mapping data for the gene causing familial Mediterranean fever (FMF), a recessively inherited disorder of inflammation. We sampled 65 Jewish, Armenian, and Arab families and typed them for eight markers from chromosome 16p. Using a new algorithm that permits multipoint calculations for a dense map of markers in consanguineous families, we obtained a maximal LOD score of 49.2 at a location 1.6 cM centromeric to D16S246. A specific haplotype at D16S283-D16S94-D16S246 was found in 76% of Moroccan and 32% of non-Moroccan Jewish carrier chromosomes, but this haplotype was not overrepresented in Armenian or Arab FMF carriers. Moreover, the 2.5-kb allele at D16S246 was significantly associated with FMF in Moroccan and non-Moroccan Jews but not in Armenians or Arabs. Since the Moroccan Jewish community represents a relatively recently established and genetically isolated founder population, we analyzed the Moroccan linkage-disequilibrium data by using Luria-Delbrück formulas and simulations based on a Poisson branching process. These methods place the FMF susceptibility gene within 0.305 cM of D16S246 (2-LOD-unit range 0.02-0.64 cM).
Apolipoprotein E (ApoE) immunoreactivity is consistently present in the senile plaques and neurofibrillary tangles of Alzheimer's disease (AD) brain. In vitro, apoE, and in particular its apoE4 isoform, can bind to and promote fibrillogenesis of the amyloid A beta peptide, the main constituent of senile plaques. These findings, together with the strong genetic association between late onset AD and the E4 allele of apoE, have strengthened the hypothesis that apoE may have a central role in the pathogenesis of AD by modulating A beta cerebral accumulation. However, apoE immunoreactivity is present in all cerebral and systemic amyloidoses tested, and tryptic apoE fragments have been identified in association with amyloid A (AA). In order to further elucidate the interaction between apoE and amyloids, we purified AA and amyloid L (AL) fibrils from patients with familial Mediterranean fever and primary amyloidosis, respectively, and studied the association of apoE with AA and AL proteins. In each case, apoE fragments, detected by Western blot, co-purified with the amyloid fibrils. Microsequencing analysis identified COOH-terminal fragments of apoE, similar to the 10-kDa fragment produced by thrombin digestion that contains the purported binding region to A beta. In vitro co-incubation of AA with purified human apoE resulted in the formation of an SDS-resistant AA.apoE complex and a higher degree of polymerization of the AA peptide. These findings and similar results obtained from AD senile plaques suggest that 1) the carboxyl-terminal fragment of apoE is complexed to amyloid fibrils and resists proteolysis in vivo and 2) apoE may promote amyloidogenesis through a conformation-dependent interaction regardless of the primary structure of the amyloid precursors.
Familial Mediterranean fever (FMF) is an autosomal-recessive disease which affects almost exclusively people of Mediterranean and Middle Eastern origin. We examined the possibility of a dominant inheritance of FMF among our 3,000 patients in Israel. Two hundred forty FMF patients were members of 77 families in which the disease affected more than one generation. In 75 of these families the occurrence of FMF in more than one generation was found to be consistent with a recessive mode of inheritance due to a high gene frequency (q) and consanguinity among parents of the patients. In 2 families, one of Ashkenazi and the other of Georgian Iraqi origin, in which FMF occurred in 4 consecutive generations, the mode of inheritance could be explained only by autosomal-dominant inheritance.
Reactive amyloidosis is a disease occurring in patients suffering from chronic infections, inflammation, and certain malignant conditions that are characterized by a considerable elevation of the acute phase reactant serum amyloid A (SAA). It is defined by the presence of extracellular deposits of fibrillar material containing amyloid A (AA) as its main component. AA is an 8.5-kd protein structurally identical to the NH2-terminal of the acute phase reactant SAA. SAA consists of a group of evolutionally conserved amphipathic proteins, encoded by a large number of genes and produced abundantly during inflammation, all suggesting an important role, probably of a neutralizing (anti-inflammatory) nature. An analysis of various aspects of SAA provides no clues to the mechanism of amyloid production, its occurrence in only selected individuals, and its preferential relationship to one isotype of SAA. Until more data is available, the present view on AA amyloidogenesis remains hypothetical.
Cystinuria is an autosomal recessive disease characterized by the development of kidney stones. Guided by the identification of the SLC3A1 amino acid-transport gene on chromosome 2, we recently established genetic linkage of cystinuria to chromosome 2p in 17 families, without evidence for locus heterogeneity. Other authors have independently identified missense mutations in SLC3A1 in cystinuria patients. In this report we describe four additional cystinuria-associated mutations in this gene: a frameshift, a deletion, a transversion inducing a critical amino acid change, and a nonsense mutation. The latter stop codon was found in all of eight Ashkenazi Jewish carrier chromosomes examined. This report brings the number of disease-associated mutations in this gene to 10. We also assess the frequency of these mutations in our 17 cystinuria families.
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Human serum amyloid P component (hSAP) and human C-reactive protein (hCRP) are normal serum constituents related to the pentraxin family of plasma proteins. hSAP has morphological and immunochemical identity and extensive sequence similarity to the amyloid P (AP) component found in normal tissues and particularly in amyloid deposits. hCRP and its proteolytic products have been previously shown to bind and to interact with various types of human leukocytes. Binding-displacement experiments with 125I-labeled hSAP and hCRP show that both proteins have specific high-affinity binding sites on normal human polymorphonuclear leukocytes (PMN) and each can compete efficiently with the binding of the other. Scatchard analysis of hSAP-displacement curves reveals a heterogeneous population of hSAP-binding sites existing on the PMN cells, among them about 300,000 low-affinity binding sites with Kd < or = 5 x 10(-6) M and about 30,000 high-affinity binding sites with Kd < or = 5 x 10(-8) M. hAP was found to be degraded by enzymes from human neutrophils to yield a mixture of low-molecular-mass peptides, similarly to the case of CRP reported previously. The binding of hSAP can be efficiently inhibited by this peptide mixture. The results suggest that both hCRP and hSAP, together with related peptides, may participate in vivo in an unknown mechanism of regulation of human neutrophils.
OBJECTIVE: To elucidate factors possibly influencing the outcome of colchicine therapy in patients with amyloidosis of familial Mediterranean fever (FMF). METHODS: Retrospective analysis of data abstracted from the charts of all 68 FMF patients with amyloidosis who presented during the study period (1974-1992) with proteinuria (> or = 0.5 gm/24 hours) and creatinine values < or = 2.5 mg/dl, received colchicine, and were followed up for > or = 5 years. RESULTS: At the end of the study period, kidney disease had worsened in 31 patients and remained stable in 22. Proteinuria had regressed in 15 patients. Deterioration was related to initial serum creatinine values > or = 1.5 mg/dl (P < 0.01) and to mean colchicine dosage < or = 1.5 mg/day (P < 0.001). The 3 groups were comparable in terms of initial urinary protein levels, duration of proteinuria, presence of hypertension, occurrence of febrile attacks, sex distribution, and proportion of non-compliant patients. CONCLUSION: The therapeutic dosage of colchicine for amyloidosis of FMF is > 1.5 mg/day. This dosage is effective only in patients with initial serum creatinine levels < 1.5 mg/dl.
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A new procedure was developed for isolation and immunochemical identification of amyloid proteins. This procedure involves extraction of amyloid proteins from tissues with aqueous acidic acetonitrile, their purification by HPLC and identification by ELISA. In this way the type of amyloid proteins was defined in amyloid-containing tissues obtained from 15 patients. The technique is simple, rapid and enables typing of amyloid proteins using only milligram amounts of tissue. This is in contrast to the conventional amyloid isolation and chemical identification technique which is laborious, time consuming and requires gram amounts of tissues. The procedure may enable the identification of the type of amyloid in biopsy specimens and thus help in evaluation of prognosis and determination of the therapeutic policy.
To study the mechanism of amyloid deposition, the nature of amyloid proteins formed in experimental murine amyloidosis, was examined. Spleen specimens, 15-60 mg, were homogenized and extracted using aqueous acidic acetonitrile, in a recently developed procedure, making it possible to obtain amyloid proteins from minute amounts of tissue. The extracted material, 1.5-4 mg, was analysed by Western blotting and ELISA using antibodies recognizing differentially proteins AA and SAA. Two immunoreactive proteins of 8 and 12 KDa were isolated and subjected to amino acid analysis and N-terminal sequence determination. The results of immunochemical and chemical examination showed that the 8 and 12 KDa proteins represented proteins AA and SAA, respectively. The data obtained provide new direct evidence for SAA in tissues during murine amyloidogenesis.
OBJECTIVE: We describe a newly defined syndrome of protracted febrile myalgia in patients with familial Mediterranean fever (FMF). METHODS: Fourteen patients with FMF were admitted with an attack of severe disabling myalgia accompanied by fever, high erythrocyte sedimentation rate, and hyperglobulinemia, lasting up to 6 weeks. RESULTS: Unlike in the classical manifestations of FMF response to corticosteroids therapy was prompt. CONCLUSION: Protracted febrile myalgia is an uncommon dramatic manifestation of FMF that may occur despite colchicine therapy and requires treatment with corticosteroids.
OBJECTIVE: To determine whether chronic lower body pain in a subpopulation of patients with familial Mediterranean fever (FMF) is due directly to the musculoskeletal manifestations of FMF or whether they are connected to mechanical problems in the low back and leg/foot or to other factors operative in fibromyalgia (FM). METHODS: In 93 consecutive patients with FMF a point count of 14 tender points (TP) was conducted by thumb palpation. Tenderness thresholds were assessed in some of the TP and of control point sites by Chatillon dolorimeter. RESULTS: In female patients with FMF dolorimeter thresholds of fibrositic and control point sites were significantly lower than in male patients with FMF (p < 0.004). Also patients with FMF with back pain and foot/leg pain are more tender than patients with FMF without this characteristic (p < 0.001). CONCLUSION: The detection of FM and definition of tenderness thresholds is relevant to this disease, since musculoskeletal complaints are common in this group of patients but not always explained by objective findings.
In order to demonstrate the effect of prophylactic colchicine treatment on the natural history of familial Mediterranean fever (FMF), a family is presented with 6 out of 9 siblings affected by FMF. Each patient represents a different stage of the amyloidotic kidney disease of FMF and the effect of continuous colchicine treatment on its course. Considered together, the members of this family present an almost complete clinical, genetic, and behavioral picture of the disease.
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Familial Mediterranean fever (FMF) is an autosomal recessive disorder of unknown pathogenesis, characterized by recurrent, self-limited attacks of fever with synovitis, peritonitis, or pleurisy. Using DNAs from affected Israeli families, we have recently mapped the gene causing FMF (designated MEF) to the short arm of chromosome 16, with two-point lod scores in excess of 20. In this report we consider the possibility of a second FMF susceptibility locus. Before discovering linkage to markers on chromosome 16, we had found suggestive evidence for linkage to chromosome 17q, with the following maximal two-point lod scores: D17S74 (pCMM86), Z = 2.47, (theta = 0.20); D17S40 (pLEW101), Z = 2.15 (theta = 0.15); D17S35 (CRI-pP3-1), Z = 1.78 (theta = 0.15); D17S46 (pLEW108), Z = 1.69 (theta = 0.18), D17S254, Z = 2.30 (theta = 0.20). Moreover, multipoint linkage analysis using D17S74 and D17S40 as fixed loci gave Z = 3.27 approximately 10 centimorgans (cM) telomeric to D17S40. Data with the chromosome 17 markers alone in our families suggested locus heterogeneity. Nevertheless, our families were not separable into complementary subsets showing linkage either to chromosome 16 or to chromosome 17. We also examined the possibility that the positive lod scores for chromosome 17 might reflect a secondary, modifying locus. By several measures of disease severity, families with positive lod scores for chromosome 17 loci had no worse disease than those with negative lod scores for these loci. We conclude that chromosome 17 does not encode a major FMF susceptibility gene for some of the families, nor does it encode a disease-modifying gene. Rather, it would appear that linkage to chromosome 17 is a "false positive" (type I) error. These results reemphasize the fact that a lod score of 3.0 corresponds to a posterior probability of linkage of 95%, with an attendant 1 in 20 chance of observing a false positive.
Colchicine is an effective medication in the prevention and treatment of amyloidosis of familial Mediterranean fever. Its therapeutic effect depends on the stage of renal disease and the drug dose. To evaluate colchicine effect in AA amyloidosis of other diseases and in primary AL amyloidosis, the literature was reviewed. Findings were that (1) the effect of colchicine in reactive amyloidosis has not been methodically studied, but anecdotal reports suggest it may be beneficial; and (2) the results of studies and case reports on the effect of colchicine in primary amyloidosis are conflicting. Because a therapeutic effect of colchicine in primary and reactive amyloidosis has been shown in sporadic cases, a prospective, controlled, multicenter study assessing the effect of colchicine in all types of amyloidosis appears to be justified. Until such a study is available, the addition of colchicine in an appropriate dose to any therapeutic regimen of patients with AA or AL amyloidosis should be considered.