Lytic to temperate switching of viral communities.

Microbial viruses can control host abundances via density-dependent lytic predator-prey dynamics. Less clear is how temperate viruses, which coexist and replicate with their host, influence microbial communities. Here we show that virus-like particles are relatively less abundant at high host densities. This suggests suppressed lysis where established models predict lytic dynamics are favoured. Meta-analysis of published viral and microbial densities showed that this trend was widespread in diverse ecosystems ranging from soil to freshwater to human lungs. Experimental manipulations showed viral densities more consistent with temperate than lytic life cycles at increasing microbial abundance. An analysis of 24 coral reef viromes showed a relative increase in the abundance of hallmark genes encoded by temperate viruses with increased microbial abundance. Based on these four lines of evidence, we propose the Piggyback-the-Winner model wherein temperate dynamics become increasingly important in ecosystems with high microbial densities; thus 'more microbes, fewer viruses'.

Additive triple DMARD combination therapy of a low dose of sulfhydryl compounds, sulfasalazine and methotrexate in the treatment of rheumatoid arthritis: a clinical trial.

To evaluate the efficacy and safety of additive triple disease modifying anti-rheumatic drug (DMARD) combination therapy of a low dose of sulfhydryl compounds ¿D-penicillamine, bucillamine or tiopronin¿, sulfasalazine (SSZ) and methotrexate (MTX) as a treatment for rheumatoid arthritis (RA) patients, we studied a total of 33 Japanese RA patients (6 males, 27 females). At 1 or 2 months after simultaneous administration of the 3 above-mentioned DMARDs was begun, significant improvements were seen in markers of joint inflammation, i.e., erythrocyte sedimentation rate and C-reactive protein in sera. At 6 months, clinical improvement judged by the physicians' overall assessment of joint symptoms and laboratory data was observed in 29 (88%) of the 33 RA patients. No marked effect was observed in the other 4 (12%) patients, however. We observed no significant adverse reaction to this therapy. This suggests that additive triple DMARD combination therapy of a low dose of sulfhydryl compounds, SSZ and MTX could be a useful drug therapy for the treatment of RA patients, even those who are refractory.

A case of Gitelman's syndrome with chondrocalcinosis.

A 45-year-old Japanese woman, treated for Bartter's syndrome for 14 years, presented with complaints of numbness in her extremities and polyarthralgia. She was diagnosed to have Gitelman's syndrome with chondrocalcinosis, which were effectively treated with spironolactone and magnesium supplementation. Gitelman's syndrome is a primary renal tubular disorder characterized by hypomagnesemia and hypocalciuria with normal calcemia. The persistent hypomagnesemia is one of the causes of chondrocalcinosis, and many cases of Bartter's syndrome with hypomagnesemia are associated with chondrocalcinosis attributed to a tubular magnesium defect. We summarize the reported cases with Bartter's syndrome and chondrocalcinosis, referring to the possibility of Gitelman's syndrome.

Collagenofibrotic glomerulonephropathy associated with immune complex deposits.

A 66-year-old Japanese male, who suffered from persistent proteinuria and leg edema, underwent renal biopsy. Light microscopy revealed marked narrowing of the glomerular capillary lumen with a diffuse accumulation of weakly PAS-positive material. By electron microscopy, abundant abnormal collagen fibers were observed predominantly in the subendothelial space and occasionally in the mesangial matrix. The fibers had a periodicity of about 60 nm and were immunoreactive for anti-type III collagen. Subendothelial electron-dense deposits were also found in some of the capillary walls. The serum level of procollagen III peptides was elevated and changed in parallel with the amount of proteinuria during the patient's clinical course. On the basis of these findings, a diagnosis of the collagenofibrotic glomerulonephropathy was made. A review of the literature, including 29 similar or identical cases, failed to reveal the etiology and pathogenesis of this disease. We suggest that this disease may be divided into two different clinical subtypes, an adult-onset type and a pediatric type.

Down regulation by iron of prostaglandin E2 production by human synovial fibroblasts.

OBJECTIVE: To examine the effect of iron on the prostaglandin (PG) E2 production by human synovial fibroblasts in vitro. METHODS: Human synovial fibroblasts were isolated from synovial tissue of rheumatoid arthritis (RA) and osteoarthritis (OA) patients and cultured in medium. Synovial fibroblasts were stimulated by human recombinant interleukin (IL) 1 beta (0.1-10 ng/ml) with or without ferric citrate (Fe-citrate, 0.01-1 mM). The amount of PGE2 in the culture medium was measured by an enzyme linked immunosorbent assay. RESULTS: The production of PGE2 by the synovial fibroblasts was increased by stimulation with IL1 beta at all concentrations tested. Fe-citrate but not sodium citrate (Na-citrate) down regulated the production of PGE2 by the synovial fibroblasts, both with and without stimulation by IL1 beta. Fe-citrate inhibited the spontaneous PGE2 production by the cells in a dose dependent manner, and a maximum inhibition by Fe-citrate was observed at the concentration of 0.1 mM with IL1 beta stimulation. The down regulation by iron was reversed by the co-addition of desferrioxamine (100 micrograms/ml), an iron chelator. CONCLUSION: Iron down regulates the PGE2 production by synovial fibroblasts in vitro.

[A case of amyopathic dermatomyositis associated with interstitial pneumonitis].

A patient (47-year old female) who had erythema similar to Gottron's sign on bilateral finger joints since two years ago, started to have polyarthralgia on bilateral knee and shoulder on the spring of 1993. Polyarthralgia was extended to both wrist and hand joints on Oct. of 1995. On the middle of Dec. 1995, she began to have exertional dyspnea and was referred and admitted in our hospital on 18th, Dec., 1995. Chest X-ray and CT scan showed the shadow for active interstitial pneumonitis on bilateral lower lung fields. Blood gas analysis indicated hypoxia (PaO2: 62.8 mmHg) and low % DLCO (64.7%). Skin eruption of face (heliotrope-like erythema) and hands (Gottron's sign) and skin biopsy (right hand) findings were compatible with that in dermatomyositis. The analysis in blood biochemistry showed no elevation for muscle enzymes. The diagnosis for amyopathic dermatomyositis (ADM) was made according to the criteria proposed by Euwer & Sontheimer (1993). The steroid pulse therapy and 50 mg per day of cyclophosphamide were immediately administered. The dyspnea and dermatitis were improved within two weeks after therapy. She is presently in remission until Jan. 1997 with the maintenance dosis of 10 mg per day of oral prednisolone.

Lobular form idiopathic glomerulonephritis with massive subendothelial and paramesangial immune deposits, a three-year follow-up case.

We report a patient with unusual glomerulonephritis. A 24-year-old Japanese female was hospitalized in October 1995 because of nephrotic syndrome. Lobular form glomerulonephritis with mesangial proliferation associated with massive wide-spread accumulation of slightly eosinophilic, periodic acid Schiff-positive amorphous materials in the luminal side of the capillary walls and paramesangial area was observed in the renal biopsy specimen. Immunofluorescent study revealed massive strong staining for IgM and C4 along the capillary walls and in the mesangium. Deposits of IgA, IgG, C3 and fibrinogen were also observed. Electron microscopy showed normal thickness of the capillary basement membrane and a large amount of subendothelial and paramesangial electron dense, finely granular deposits without fibrils or tubular structures. There were no clinical or laboratory findings of systemic diseases, such as systemic lupus erythematosus and cryoglobulinemia. Therefore, we believed that this case involved an unusual idiopathic glomerular disease with massive subendothelial and paramesangial immune deposits. Glomerulonephritis in this patient appeared to be resistant to treatment with corticosteroids and that this glomerulopathy may be a progressive disease as shown during the 3-year observation. Furthermore, our patient had idiopathic hyperprolactinemia and subclinical hypothyroidism. However, the relationship between glomerulonephritis and endocrinopathy in our patient is unknown.

[A case of malignant rheumatoid arthritis associated with myelodysplastic syndrome].

The patient (57 year-old female) complained of high fever and polyarthralgia in autumn of 1994, when a diagnosis of refractory anemia, a type of myelodysplastic syndrome (MDS) was made by severe anemia (RBC: 154 x 10(4)/microliters), leucopenia (2,200/microliters) and erythroid hyperplasia, ring-nucleated myelocyte, micromegakaryocyte and less than 5% of blasts in bone marrow smear. In her further clinical course, symptoms such as episcleritis, mononeuritis multiplex, skin ulcers on bilateral lower legs and circulating disturbance on left lower leg with high titer of rheumatoid factor were appeared in six months, suggesting malignant rheumatoid arthritis (MRA). She also had rectal cancer notified by anal bleeding. In spite of the administration of large doses of glucocorticoid and disease modifying anti-rheumatic drugs, circulating disturbance on left lower leg which might be caused by vasculitis was worsened to show tissue necrosis. Finally, she died of disseminated intravascular coagulation. The association of MDS with rheumatic disorders such as rheumatoid arthritis, Behçet disease and Sjögren's syndrome is not rarely reported. However, this is the first case of MDS associated with MRA.

Anti-neutrophil cytoplasmic antibody in patients with systemic lupus erythematosus is unrelated to clinical features.

To investigate the incidence, the specificity and clinical significance of positivity for serum anti-neutrophil cytoplasmic antibody (ANCA) in 31 patients with systemic lupus erythematosus (SLE), the indirect immunofluorescence (IIF) technique and enzyme-linked immunosorbent assay (ELISA) were used to measure ANCA. Purified myeloperoxidase (MPO), lactoferrin (LF), cathepsin-G (CTG) and elastase (HLE) served as ANCA antigens for ELISA. Thirteen (42%) of the 31 SLE patients showed positivity for perinuclear, but not cytoplasmic, ANCA by IIF. Five of 31 sera were positive for MPO, 10 for LF, 1 for CTG and 0 for HLE by ELISA. Patients positive for ANCA had a higher score of SLE disease activity index (SLEDAI) than those without ANCA. There was no correlation between ANCA positivity, clinical manifestations, or organic involvement. While the ANCA in patients with SLE reflected disease activity, it was unrelated to organic involvement.

Positivity for antinuclear antibody in patients with advanced rheumatoid arthritis.

Some patients with rheumatoid arthritis (RA) as well as those with other collagen diseases are positive for antinuclear antibody (ANA). We investigated the frequency of positivity for ANA in 104 patients with RA and evaluated the clinical features and laboratory data in the ANA-positive and -negative groups. The presence of ANA in sera was studied by indirect immunofluorescence using HEp-2 cells as the antigen substrate. Sera with a positive fluorescence at a dilution of 1:20 were considered to be positive for ANA. Of the 104 patients, 39 (37.5%) were positive for ANA. The staining pattern in the positive cases varied, but most were speckled (64.1%) and homogeneous (48.7%). A small number showed a nucleolar (20.5%) or a centromere (10.3%) pattern. None showed a shaggy pattern. The ANA titer was lower in RA patients compared with those with other collagen-related diseases such as systemic lupus erythematosus or progressive systematic sclerosis. None of the patients positive for ANA with either a nucleolar or centromere staining pattern had progressive systemic sclerosis or the CREST syndrome. One patient each had Raynaud's phenomenon and pulmonary fibrosis. There was no correlation between ANA positivity and indicators of joint inflammation. The prevalence of ANA positivity in patients with advanced or prolonged disease was higher than those with early stages or short durations. There was no correlation with drug therapy.