A case of pulmonary arterial hypertension complicated by anti-neutrophil cytoplasmic antibody-associated vasculitis and systemic sclerosis

Pulmonary arterial hypertension (PAH) is a rare complication of ANCA-associated vasculitis (AAV). We report a 37-year-old man with PAH complicated by both AAV and SSc who presented with dyspnea, cardiac enlargement, positive myeloperoxidase (MPO)-ANCA, anti-centromere antibodies, proteinuria, and urinary casts. Elevated pulmonary arterial pressure (58/22/34 mmHg) and low PAWP (2 mmHg) were confirmed by right heart catheterization. Treatment with glucocorticoids (GC) decreased urinary protein and serum MPO-ANCA; however, PAH did not respond to GC. Therefore, a combination of beraprost, bosentan, and tadalafil was needed. The differences in responses to GC suggest that the pathophysiology of nephropathy is different from that of PAH. We considered that nephropathy was associated with AAV but that PAH was associated with SSc in the present case. We discuss the pathophysiology and treatment response of PAH complicated by AAV, referring to nine past cases

Oral dextran sulfate sodium administration induces peripheral spondyloarthritis features in SKG mice accompanied by intestinal bacterial translocation and systemic Th1 and Th17 cell activation

BACKGROUND: Spondyloarthritis (SpA) is an autoimmune and autoinflammatory musculoskeletal disease characterised by systemic enthesitis. Recent research has focused on subclinical inflammatory bowel disease (IBD) in SpA pathogenesis. SKG mice, harbouring the Zap70 W163C mutation, increase autoreactive Th17 cells intrinsically, and in a conventional environment, they exhibit spontaneous arthritis with fungal factors. Under SPF conditions, they show SpA features, including enteritis, after peritoneal injection of β-1, 3-glucan. This study aimed to clarify whether oral dextran sulfate sodium (DSS) administration, utilised in IBD model mice, can provoke SpA features in SKG mice under SPF conditions, focusing on the relationship between gut microorganisms and SpA pathogenesis. METHODS: BALB/c and SKG mice were administered oral DSS, and their body weights, arthritis, and enthesitis scores were recorded. In another cohort, antibiotics (meropenem and vancomycin) or an anti-fungal agent (amphotericin B) was administered orally before DSS administration. The splenic Th1 and Th17 cell populations were examined before and after DSS administration using flow cytometry. Furthermore, the amount of circulating bacterial DNA in whole blood was measured by absolute quantitative polymerase chain reaction (qPCR), and the number and characteristics of bacterial species corresponding to these circulating DNA were analysed by next-generation sequencing (NGS). RESULTS: Ankle enthesitis as a peripheral SpA feature was elicited in half of DSS-administered SKG mice, and none of the BALB/c mice. Pre-administration of antibiotics suppressed enthesitis, whilst an anti-fungal agent could not. Th1 and Th17 cell levels in the spleen increased after DSS administration, and this was suppressed by pre-administration of antibiotics. SKG mice have a larger amount of bacterial DNA in whole blood than BALB/c mice before and 1 day after the initiation of DSS administration. The number of bacterial species in whole blood increased after DSS administration in BALB/c and SKG mice. Some genera and species significantly specific to the DSS-treated SKG mouse group were also detected. CONCLUSION: Oral DSS administration alone elicited peripheral enthesitis in SKG mice with bacterial translocation accompanied by increased splenic Th1 and Th17 cell levels. Pre-administration of antibiotics ameliorated these DSS-induced SpA features. These findings suggest that intestinal bacterial leakage plays a pivotal role in SpA pathogenesis

Urinary sodium-to-potassium ratio associates with hypertension and current disease activity in patients with rheumatoid arthritis: a cross-sectional study

BACKGROUND: Excessive salt intake is thought to exacerbate both development of hypertension and autoimmune diseases in animal models, but the clinical impact of excessive salt in rheumatoid arthritis (RA) patients is still unknown. We performed a cross-sectional study to clarify the associations between salt load index (urinary sodium-to-potassium ratio (Na/K ratio)), current disease activity, and hypertension in an RA population. METHODS: Three hundred thirty-six participants from our cohort database (KURAMA) were enrolled. We used the spot urine Na/K ratio as a simplified index of salt loading and used the 28-Joint RA Disease Activity Score (DAS28-ESR) as an indicator of current RA disease activity. Using these indicators, we evaluated statistical associations between urinary Na/K ratio, DAS28-ESR, and prevalence of hypertension. RESULTS: Urinary Na/K ratio was positively associated with measured systolic and diastolic blood pressure and also with prevalence of hypertension even after covariate adjustment (OR 1.34, p <  0.001). In addition, increased urinary Na/K ratio was significantly and positively correlated with DAS28-ESR in multiple regression analysis (estimate 0.12, p <  0.001), as was also the case in gender-separated and prednisolone-separated sub-analyses. CONCLUSION: Urinary Na/K ratio was independently associated with current disease activity as well as with prevalence of hypertension in RA patients. Thus, dietary modifications such as salt restriction and potassium supplementation should be investigated as a potential candidate for attenuating both disease activity and hypertension in RA patients

Composition of dirt layers in the bare ice areas near the Yamato Mountains in Queen Maud Land and the Allan Hills in Victoria Land, Antarctica

Dirt layers of tephra were found on the bare ice surface in the Meteorite Ice Field near the Yamato Mountains, Queen Maud Land, and in the bare ice area near the Allan Hills, Victoria Land. Their age is unknown but supposed to be several to several tens of thousands of years. Their constituent fragments are well-sorted and composed mainly of volcanic glass shards with minor amounts of crystal fragments. Glass shards of tephra from the Yamato Mountains region have a composition of tholeiitic andesite which is low alkali and high iron but not so enriched in titanium, and the associated crystal fragments consist of calcic plagioclase, subcalcic clinopyroxene, orthopyroxene and magnetite. Such character of island arc tholeiite of the tephra indicates its source to be some volcano in the South Sandwich Islands. On the other hand, the tephra from the Allan Hills region is composed of glass shards with trachybasaltic composition and crystal fragments of titanaugite, calcic plagioclase, kaersutite, olivine, rhonite and titanomagnetite. Some young volcano of the McMurdo Volcanic Group is suggested to be a possible source of the tephra

Some characteristics of drifting snow at Mizuho Station, East Antarctica, 1982

Several measurements on drifting snow were carried out at Mizuho Station (70°42′S, 44°20′E, 2230m, above sea level)) East Antarctica, in 1982. Visibility was correlated to wind velocity on a logarithmic plot; it was proportional to about the -8 power of wind velocity over a year. This is explained by the reciprocal relation of visibility to drift density and the power relation of drift density to wind velocity. Moreover, visibility changed with the seasonal variation of daylight. The repose angle of drifting snow particles was observed by measuring the inclination of a cone shape deposit formed in sub-surface chamber. The repose angle was more than 80° in the case of snow falling and less than 80° in the case of no precipitation. The angle in the case of no precipitation showed a temperature dependence. The fall velocity of drifting snow particles in still air was observed. The fall velocity was between 0.3 and 0.9m/s and depended on wind velocity and snow particle shape. This dependence is explained by the change of particle size or drag coefficient

Dirt layers and atmospheric transportation of volcanic glass in the bare ice areas near the Yamato Mountains in Queen Maud Land and the Allan Hills in Victoria Land, Antarctica

Dirt layers containing volcanic ash fragments were found on the bare ice surface in the Meteorite Ice Field near the Yamato Mountains, Queen Maud Land, and near the Allan Hills, Victoria Land. The grain size analysis of volcanic ash fragments shows that the mean grain size in the Allan Hills region is larger than that in the Yamato Mountains region. This fact indicates that the volcanic sources of the dirt layer in the Yamato Mountains region is farther away than that for the Allan Hills. Based upon the equations describing the transport of volcanic ash fragments, the distance of atmospheric transportation can be predicted by the grain size distribution, and, furthermore, the tephra sources are estimated. The age of ice-containing tephra is also discussed

Observation of snow drift flux at Mizuho Station, East Antarctica, 1982

Continuous observation of snow drift flux was carried out at Mizuho Station (70°42′S, 44°20′E, 2230m above sea level), East Antarctica, in 1982. Snow drift flux at 1m height was well correlated with wind velocity. The correlation coefficient on a logarithmic plot was between 0.8 and 0.9. The drift flux was proportional to about the 8 power of wind velocity through the year. The power decreased above -20℃. The drift flux increased when precipitation was observed. From the variation of drift flux, precipitation intensity can be estimated

Regional difference of attenuation of radio waves within Antarctic ice sheet

The attenuation of radio waves within the ice sheet is caused by absorption loss due to dielectric and electric properties of ice and geometric loss due to spreading of radio waves. The dielectric structure of the ice sheet can be derived by estimating the attenuation. This estimation is useful for the design of the future radio echo sounder. The inland traverse party of the 23rd Japanese Antarctic Research Expedition in 1982 measured an ice thickness by radio echo sounding which operated on 60MHz. Calculations of the attenuation rate of radio waves were made by reading the rate of decrease of the strength of internal echoes on the photographs of the A-scope display records. Values of the attenuation coefficient (dB/100m) in the present study change between about 1.2 and about 3,and become smaller with increase of surface elevation of the ice sheet. But the attenuation coefficient in the bare ice field, the Meteorite Ice Field, around the Yamato Mountains is remarkably high. The regional difference of the attenuation coefficient is caused mainly by the temperature distribution with depth in the ice sheet. But it is considered that the high value of the effective attenuation coefficient in the bare ice field is due to not only different temperature distribution but also different dielectric properties of the bare ice

Search and collection of Yamato meteorites in the 1982-83 field season,Antarctica

Search and collection of Antarctic meteorites were carried out by the inland traverse party of the 23rd Japanese Antarctic Research Expedition (JARE-23) in the Meteorite Ice Field near the Yamato Mountains in 1982-83. Collected meteorites (named Yamato-82 meteorites) are 211 specimens, and their total weight is over 35kg. A preliminary study revealed that the Yamato-82 meteorites included 10 carbonaceous chondrites, 5 diogenites, 13 eucrites, 3 unclassified achondrites and a large number of chondrites. Among them, more than 50 specimens were found in the limited area within 1km in diameter, 25km south from Kuwagata Nunatak of the Minami-Yamato Nunataks. Such a meteorite-concentrated area as this one suggests that the sub-ice mountains may exist in the bare ice area and the ice flow carrying meteorites forms a horizontal convergence