Histopathological Features of Mycobacterium chelonae Infection in Two Farmed Japanese Pufferfish (Takifugu rubripes)

Granulomatous lesions were observed in the swim bladder, kidney, spleen and gills of two farmed Japanese pufferfish (Takifugu rubripes) infected with Mycobacterium chelonae. Three types of lesions were noted: unencapsulated clusters of epithelioid cells without central necrosis (type 1), encapsulated granulomas without central necrosis (type 2) and encapsulated granulomas with central necrosis (type 3). Type 3 lesions occurred most frequently in the swim bladder, while type 1 and type 2 lesions occurred frequently in the kidney and spleen, and the gills exhibited mostly type 1 lesions. This suggests that the lesions in the swim bladder were more fully developed than those occurring elsewhere and that the swim bladder may be more susceptible to infection with M. chelonae. This is the first report describing the histopathological features of M. chelonae infection in Tetraodontidae.

Equol inhibits growth and spore formation of Clostridioides difficile

AIMS

Equol is a nonsteroidal oestrogen of the isoflavone class. We investigated the antibacterial ability of equol with respect to the growth rate, toxin production and spore-forming abilities of Clostridioides difficile BI/027/NAP1.

METHODS AND RESULTS

Isoflavones, or female hormones, were added to bacterial culture, which was grown at 35°C. The absorbance of the culture was measured at various time points for evaluating the growth inhibition. The toxin levels in the media and morphological changes were also assessed. To evaluate the influence of equol on the sporulation of C. difficile, cells were collected at various time points from the equol-supplemented culture and the number of spores was counted. Our results show that equol inhibits bacterial growth in a concentration-dependent manner. However, it does not inhibit the production of toxin by C. difficile. Other isoflavones and female hormones did not inhibit the C. difficile growth. At the 14th day, approximately 600 spores were present in the control medium and only six were seen in the equol-containing medium.

CONCLUSION

Our results suggest that equol may directly inhibit the C. difficile growth in a concentration-dependent manner and spore formation.

SIGNIFICANCE AND IMPACT OF THE STUDY

This is the first report on the antimicrobial ability of equol.

Pressure-induced stacking disorder in boehmite

The structure of an aluminum layered hydroxide, boehmite (γ-AlOOH), as a function of pressure was studied by using in situ synchrotron X-ray and neutron diffraction. Peak broadening, which is only found for hkl (h ≠ 0) peaks in the X-ray diffraction patterns, is explained by stacking disorder accompanying a continuously increasing displacement of the AlO6 octahedral layer along the a-axis. This finding could be the first experimental result for pressure-induced stacking disorder driven by continuous layer displacement. The magnitude of the layer displacement was estimated from the X-ray scattering profile calculation based on the stacking disordered structure model. Hydrogen bond geometries of boehmite, obtained by structure refinements of the observed neutron diffraction patterns for the deuterated sample up to 10 GPa, show linearly approaching O-D covalent and DO hydrogen bond distances and they merge below 26 GPa. Pressure-induced stacking disorder makes the electrostatic potential of hydrogen bonds asymmetric, yielding less chance for proton-tunnelling.

Pathophysiological characteristics of non-alcoholic steatohepatitis-like changes in cholesterol-loaded type 2 diabetic rats

Spontaneously Diabetic Torii (SDT) fatty rats, a new obese diabetic model, reportedly presented with features of non-alcoholic steatohepatitis (NASH) after 32 weeks of age. We tried to accelerate the onset of NASH in SDT fatty rats using dietary cholesterol loading and noticed changes in the blood choline level which is expected to be a NASH biomarker. Body weight and biochemical parameters were measured from 8 to 24 weeks of age. At 16, 20, 24 weeks, pathophysiological analysis of the livers were performed. Hepatic lipids, lipid peroxides, and the expression of mRNA related to triglyceride (TG) synthesis, inflammation, and fibrosis were evaluated at 24 weeks. Hepatic fibrosis was observed in SDT fatty rats fed cholesterol-enriched diets (SDT fatty-Cho) from 16 weeks. Furthermore, hepatic lipids and lipid peroxide were significantly higher in SDT fatty-Cho than SDT fatty rats fed normal diets at 24 weeks. Hepatic mRNA expression related to TG secretion decreased in SDT fatty-Cho, and the mRNA expression related to inflammation and fibrosis increased in SDT fatty-Cho at 24 weeks. Furthermore, SDT fatty-Cho presented with increased plasma choline, similar to human NASH. There were no significant changes in the effects of feeding a cholesterol-enriched diet in Sprague-Dawley rats. SDT fatty-Cho has the potential to become a valuable animal model for NASH associated with type 2 diabetes and obesity.

Medial and lateral laxity in knees with advanced medial osteoarthritis

OBJECTIVE

An increase in coronal laxity is recognized as a risk factor for progression of knee osteoarthritis (OA). The purpose of this study was to evaluate coronal laxity, which was defined as the angular motion from the neutral, unloaded (baseline) position to the loaded position, in patients with advanced medial knee OA.

METHOD

Preoperative coronal laxity was assessed using radiographs in patients with medial knee OA undergoing total knee arthroplasty by applying a force of 150 N with an arthrometer. A consecutive series of 211 knees with OA and 40 normal control knees were examined. A knee with OA was defined as clinically "balanced" when the difference between medial and lateral laxity was 3° or less. Values are expressed as median [25^th, 75^th percentile].

RESULTS

The laxity was 4° [3, 5] from the baseline on the medial side and 3° [2, 4] on the lateral side. The distribution of medial and lateral laxity indicated that 90% (189/211) of patients fell within 3°. The equivalence test showed that the medial and lateral laxity was similar, with an equivalence margin of 3° (P < 0.001). In the control knees, the laxity was 3° [2, 4] from the baseline on the medial side and 2° [2, 4] on the lateral side. The differences between the knees with advanced OA and the controls were significant (P = 0.005, medial; P = 0.006, lateral).

CONCLUSION

This study showed that a clinically balanced knee was maintained even in patients with advanced medial knee OA.

Intermetallic: A Pseudoelement for Catalysis

A clear correlation between electronic structure and CO₂ selectivity for steam reforming of methanol (SRM) was obtained with PdZn, PtZn, NiZn, and PdCd intermetallics on the basis of experiments and calculations. In order to rule out the effects of oxide supports, the intermetallic powders were simply prepared by alloying in an arc furnace followed by crushing in a mortar. PdZn and PdCd exhibit valence electronic densities of states similar to that of Cu and significant chemical shifts (larger than 1 eV) of Pd 3d states with respect to pure Pd, as verified by high-resolution hard X-ray photoelectron spectroscopy (HXPS) measurements and density functional theory (DFT) calculations. Consequently, they show the similar high selectivity of CO₂ for the SRM reaction. However, this is not the case for PtZn and NiZn because of the slight differences in their valence electronic structures from that of PdZn. The interval between the Fermi level and the top of the d band is closely related to the selectivity of CO₂ for the SRM: the larger the interval is, the higher is the selectivity of CO₂. According to DFT calculations for bulk PdZn performed by Chen et al. ( Phys. Rev. B 2003 , 68 , 075417 ), the (111) and (100) surfaces exposing Zn and Pd in an equimolar ratio are more stable than the (001) or (110) surfaces terminated by alternative Zn or Pd layers. First-principles slab calculations for PdZn, PtZn, and NiZn show that bond breaking on the surface leads to a reduction in the d bandwidth but that the d band for stable (111) or (100) surfaces remains essentially unchanged from that of the bulk. It is intriguing that PdZn and PdCd do not contain Cu but show similar valence electronic structure and catalytic selectivity, and hence, a concept is proposed where PdZn and PdCd are regarded as pseudoelements of Cu. The basis of this concept is like electronic structure, like catalysis, which has been demonstrated by experiments and calculations. This is a logical way to enable us to look for new catalysts in which precious metals are partially or completely replaced by base metals. We do not expect that this concept can be applied to all catalytic reactions, but this approach is one of most promising ways to derive a better understanding of the origin of catalytic mechanisms and eventually allow us to design useful catalysts intentionally in the future. This Account reviews the authors' published works on this topic.

Pathophysiological analysis of the progression of hepatic lesions in STAM mice

Nonalcoholic steatohepatitis (NASH) is a current health issue since the disease often leads to hepatocellular carcinoma; however, the pathogenesis of the disease has still not been fully elucidated. In this study, we investigated the pathophysiological changes observed in hepatic lesions in STAM mice, a novel NASH model. STAM mice, high fat-diet (HFD) fed mice, and streptozotocin (STZ) treated mice were prepared, and changes over time, such as biological parameters, mRNA expression, and histopathological findings, were evaluated once animal reached 5, 7, and 10 weeks of age. STZ mice presented with hyperglycemia and an increase in oxidative stress in immunohistochemical analyses of Hexanoyl-lysine: HEL from 5 weeks, with fibrosis in the liver also being observed from 5 weeks. HFD mice presented with hyperinsulinemia from 7 weeks and the slight hepatosteatosis was observed at 5 weeks, with changes significantly increasing until 10 weeks. STAM mice at 10 weeks showed significant hepatic changes, including hepatosteatosis, hypertrophic hepatocytes, and fibrosis, indicating pathological changes associated with NASH. These results suggested that the increase in oxidative stress with hyperglycemia triggered hepatic lesions in STAM mice, and insulin resistance promoted lesion formation with hepatic lipid accumulation. STAM mice may be a useful model for elucidating the pathogenesis of NASH with diabetes.

Serum ferritin level is a prognostic marker in patients with peripheral T-cell lymphoma

INTRODUCTION

The prognostic value of serum ferritin level in patients with peripheral T-cell lymphoma (PTCL) remains unknown.

METHODS

We retrospectively analyzed clinical data from 78 consecutive patients with newly diagnosed PTCL that were treated with anthracycline-containing regimens between 1998 and 2011.

RESULTS

The patients consisted of 50 males and 28 females with a median age of 64 years (range, 16-83 years). The subtypes of PTCL were 39 PTCL, not otherwise specified and 39 angioimmunoblastic T-cell lymphoma (AITL). The median observation period for the surviving patients was 50 months. The overall survival (OS) was poorer in patients with serum ferritin level above the upper normal limit (n = 28), compared with patients with serum ferritin level within normal range (n = 50; 4-year OS: 23% vs. 72%; P < 0.001). In the multivariate analysis, poor performance status (P = 0.006) and elevated serum ferritin level (P = 0.018) were independent risk factors for poor OS.

CONCLUSION

Serum ferritin level is a useful prognostic marker for PTCL.