Cd-content and temperature dependences of hyperfine fields in CdxFe3-xO4

Cd-content and temperature dependences of hyperfine fields in CdxFe3-xO4 (0 ≤ x ≤ 0.5) were investigated by means of time-differential perturbed angular correlation spectroscopy with the 111Cd(←111In) probe. It was found that Cd2+ ions selectively occupy the tetrahedral A site in the spinel structure in all the range of the present Cd content x. The magnetic transition temperature TC becomes lower with increasing x due to the interference of the long-range ordering of Fe spins as a result of expansion of the lattice constants by Cd doping. The measurement of room-temperature hyperfine fields at different x shows that the supertransferred magnetic hyperfine field (SMHF) at the probe decreases as x increases in the range of 0 ≤ x ≤ 0.5. Isothermal measurements at 15 K revealed a contrastive phenomenon for the Cd contents up to x = 0.4: the SMHF becomes great with increasing x; however, this increasing trend of the SMHF turns to reduction at x = 0.46. These observations can be explained based on the effect of Cd doping on the antiferromagnetic coupling between Fe ions in the A and B sites.

Evaluation of Brain Atrophy after One Year of Whole Brain Irradiation Using Voxel Based Morphometry

PURPOSE/OBJECTIVE(S)

Whole-brain irradiation has often been used for metastatic brain tumors and in prophylactic irradiation, but there are few reports on the frequency of cognitive decline and brain atrophy. We attempted to adapt an objective method of measuring brain atrophy to patients after whole-brain irradiation, Using Voxel based morphometry (VBM) measured from MRI to determine if brain atrophy has occurred one year after whole brain irradiation. VBM is a method to measure the change in signal intensity when an atrophic brain is transformed into a normal brain by Deformable Image Registration.

MATERIALS/METHODS

We use VBM to measure brain atrophy before and one year after irradiation in patients who received whole brain irradiation at our institution. The MRI used for the analysis was a contrast-enhanced T1-weighted image, Sagittal cross-sectional images of 1 mm thickness were obtained from the whole brain using the 3D variable flip angle turbo spin echo sequence, which is clinically used at our hospital for the cancer patient's management. The subjects were 28 patients who had undergone whole-brain irradiation at our hospital and for whom MRIs were available before treatment and after one year. The cases analyzed included patients who received prophylactic Cranial irradiation (PCI) in cases of small cell lung cancer obtained complete remission. Z-scores obtained from the medial temporal lobe were compared before and after whole brain irradiation treatment to quantitatively assess brain atrophy. The Z-score is the normalized difference between the voxel values obtained from the normal group average and the individual case. There were 15 cases of lung cancer, 5 cases of malignant lymphoma, 5 cases of breast cancer, and 3 cases of various types of cancer, with an average age of 65 years. Cases with tumors or brain edema in the vicinity of the hippocampus were excluded. Various irradiation doses were used, but the commonly used radiation doses were 23.4 Gy/13Fr (lymphoma), 25 Gy/10 Fr (PCI), 35 Gy/14 Fr (multiple metastasis).

RESULTS

A Paired-samples one sided t-test was performed to Mean z-score of positive values within the medial temporal lobe before and one year after whole brain irradiation. This number reflects the degree of atrophy within the region of interest and is determined as mild atrophy if it is greater than 1.0. The mean Z-score was found to increase at a risk of 0.01 after whole brain irradiation. This means that brain atrophy is progressing after whole brain irradiation.

CONCLUSION

Hippocampal atrophy becomes apparent about a year after whole brain irradiation. It suggests that brain atrophy occurs after radiotherapy. The problem with this study is that the effects of chemotherapy-induced brain atrophy and aging cannot be ruled out.

Activation of Lactate Receptor Positively Regulates Skeletal Muscle Mass in Mice

G protein-coupled receptor 81 (GPR81), a selective receptor for lactate, expresses in skeletal muscle cells, but the physiological role of GPR81 in skeletal muscle has not been fully elucidated. As it has been reported that the lactate administration induces muscle hypertrophy, the stimulation of GPR81 has been suggested to mediate muscle hypertrophy. To clarify the contribution of GPR81 activation in skeletal muscle hypertrophy, in the present study, we investigated the effect of GPR81 agonist administration on skeletal muscle mass in mice. Male C57BL/6J mice were randomly divided into control group and GPR81 agonist-administered group that received oral administration of the specific GPR81 agonist 3-Chloro-5-hydroxybenzoic acid (CHBA). In both fast-twitch plantaris and slow-twitch soleus muscles of mice, the protein expression of GPR81 was observed. Oral administration of CHBA to mice significantly increased absolute muscle weight and muscle weight relative to body weight in the two muscles. Moreover, both absolute and relative muscle protein content in the two muscles were significantly increased by CHBA administration. CHBA administration also significantly upregulated the phosphorylation level of p42/44 extracellular signal-regulated kinase-1/2 (ERK1/2) and p90 ribosomal S6 kinase (p90RSK). These observations suggest that activation of GRP81 stimulates increased the mass of two types of skeletal muscle in mice in vivo. Lactate receptor GPR81 may positively affect skeletal muscle mass through activation of ERK pathway.

Brain-derived neurotrophic factor from microglia regulates neuronal development in the medial prefrontal cortex and its associated social behavior

Microglia and brain-derived neurotrophic factor (BDNF) are essential for the neuroplasticity that characterizes critical developmental periods. The experience-dependent development of social behaviors-associated with the medial prefrontal cortex (mPFC)-has a critical period during the juvenile period in mice. However, whether microglia and BDNF affect social development remains unclear. Herein, we aimed to elucidate the effects of microglia-derived BDNF on social behaviors and mPFC development. Mice that underwent social isolation during p21-p35 had increased Bdnf in the microglia accompanied by reduced adulthood sociability. Additionally, transgenic mice overexpressing microglia Bdnf-regulated using doxycycline at different time points-underwent behavioral, electrophysiological, and gene expression analyses. In these mice, long-term overexpression of microglia BDNF impaired sociability and excessive mPFC inhibitory neuronal circuit activity. However, administration of doxycycline to normalize BDNF from p21 normalized sociability and electrophysiological functions; this was not observed when BDNF was normalized from a later age (p45-p50). To evaluate the possible role of BDNF in human sociability, we analyzed the relationship between adverse childhood experiences and BDNF expression in human macrophages, a possible substitute for microglia. Results show that adverse childhood experiences positively correlated with BDNF expression in M2 but not M1 macrophages. Thus, microglia BDNF might regulate sociability and mPFC maturation in mice during the juvenile period. Furthermore, childhood experiences in humans may be related to BDNF secretion from macrophages.

Influence of fetal hiccups on Doppler blood flow waveform of fetal arteries: Difference among arteries

BACKGROUND

A few studies have been reported on the influence of fetal hiccups on umbilical artery. The aim of this study is to clarify the influence of fetal hiccups on Doppler blood flow waveform (DBFW) of some fetal arteries, and to show the difference in these influences among fetal arteries.

OBJECTIVE

DBFW of umbilical artery, descending aorta, and middle cerebral artery were recorded at hiccups in normal fetuses between 34th and 40th gestational weeks. The changes on DBFW were classified into three shapes by the direction and the size of the changes. Shape 1: sharp decrease but not to the baseline, Shape 2: sharp decrease to the baseline (absence), and Shape 3: reverse flow.

RESULTS

At all hiccups, the changes on DBFW of these arteries were observed. These changes were classified into three shapes. Changes of umbilical artery were widely distributed in three shapes depending on when hiccup occurred during cardiac cycle. On the other hand, most changes of the descending aorta and middle cerebral artery were Shape 3 whenever the hiccup occurred during cardiac cycle.

CONCLUSION

The changes on DBFW of fetal arteries were observed at all hiccups. Changes of umbilical artery were widely distributed in three shapes depending on when hiccup occurred during cardiac cycle. On the other hand, most changes of descending aorta and middle cerebral artery were Shape 3. This is the first study clarified the influence of fetal hiccups on DBFW of some fetal arteries, and showed the difference in these influences among fetal arteries.

A [4Fe-4S] cluster resides at the active center of phosphomevalonate dehydratase, a key enzyme in the archaeal modified mevalonate pathway

The recent discovery of the archaeal modified mevalonate pathway revealed that the fundamental units for isoprenoid biosynthesis (isopentenyl diphosphate and dimethylallyl diphosphate) are biosynthesized via a specific intermediate, trans-anhydromevalonate phosphate. In this biosynthetic pathway, which is unique to archaea, the formation of trans-anhydromevalonate phosphate from (R)-mevalonate 5-phosphate is catalyzed by a key enzyme, phosphomevalonate dehydratase. This archaea-specific enzyme belongs to the aconitase X family within the aconitase superfamily, along with bacterial homologs involved in hydroxyproline metabolism. Although an iron–sulfur cluster is thought to exist in phosphomevalonate dehydratase and is believed to be responsible for the catalytic mechanism of the enzyme, the structure and role of this cluster have not been well characterized. Here, we reconstructed the iron–sulfur cluster of phosphomevalonate dehydratase from the hyperthermophilic archaeon Aeropyrum pernix to perform biochemical characterization and kinetic analysis of the enzyme. Electron paramagnetic resonance, iron quantification, and mutagenic studies of the enzyme demonstrated that three conserved cysteine residues coordinate a [4Fe-4S] cluster—as is typical in aconitase superfamily hydratases/dehydratases, in contrast to bacterial aconitase X-family enzymes, which have been reported to harbor a [2Fe-2S] cluster.

d-amino acid auxotrophic Escherichia coli strain for in vivo functional cloning of novel d-amino acid synthetic enzyme

Various d-amino acids have been found in a wide range of organisms, including mammals. Although the physiological functions of various d-amino acids have been reported or suggested, the molecular basis of these biological functions has been elucidated in only a few cases. The identification of a d-amino acid biosynthetic enzyme is a critical step in understanding the mechanism of the physiological functions of d-amino acids. While in vivo functional screening can be a powerful tool for identifying novel metabolic enzymes, none of the existing organisms exhibit growth dependent on d-amino acid other than d-Ala and d-Glu. Here, we report the first organism that exhibits non-canonical d-amino acid auxotrophy. We found that an Escherichia coli strain lacking the major d-Ala and d-Glu biosynthetic enzymes, alr, dadX, and murI, and expressing the mutated d-amino acid transaminase (DAAT) gene from Bacillus sp. YM-1 (MB3000/mdaat⁺ ) grew well when supplemented with certain d-amino acid. A multicopy suppression study with plasmids encoding one of the 51 PLP-dependent enzymes of E. coli showed that MB3000/mdaat⁺ could detect weak and moonlighting racemase activity, such from cystathionine β-lyase (MetC) and a negative regulator of MalT activity/cystathionine β-lyase (MalY)-these exhibit only a few tenths to a few thousandths of the racemization activity of canonical amino acid racemases. We believe that this unique platform will contribute to further research in this field by identifying novel d-amino acid-metabolizing enzymes.

Dynamic complex opto-magnetic holography

Despite recent significant progress in real-time, large-area computer-generated holography, its memory requirements and computational loads will be hard to tackle for several decades to come with the current paradigm based on a priori calculations and bit-plane writing to a spatial light modulator. Here we experimentally demonstrate a holistic approach to serial computation and repeatable writing of computer-generated dynamic holograms without Fourier transform, using minimal amounts of computer memory. We use the ultrafast opto-magnetic recording of holographic patterns in a ferrimagnetic film with femtosecond laser pulses, driven by the on-the-fly hardware computation of a single holographic point. The intensity-threshold nature of the magnetic medium allows sub-diffraction-limited, point-by-point toggling of arbitrarily localized magnetic spots on the sample, according to the proposed circular detour-phase encoding, providing complex modulation and symmetrical suppression of upper diffractive orders and conjugated terms in holographically reconstructed 3-D images.

Holography recreates both the amplitude and wave front of a three dimensional object, meaning that the observer perceives the image in the nearly same way as they would the true object. Creating such holographic images is challenging computationally, and requires extremely fast display update. Here, the authors combine a fast memoryless computation algorithm with the ultra-rapid writing based on all-optical switching of a ferrimagnetic film.

Cell death signalling is competitively but coordinately regulated by repressor-type and activator-type ethylene response factors in tobacco (Nicotiana tabacum) plants

Ethylene response factors (ERFs) comprise one of the largest transcription factor families in many plant species. Tobacco (Nicotiana tabacum) ERF3 (NtERF3) and other ERF-associated amphiphilic repression (EAR) motif-containing ERFs are known to function as transcriptional repressors. NtERF3 and several repressor-type ERFs induce cell death in tobacco leaves and are also associated with a defence response against tobacco mosaic virus (TMV). We investigated whether transcriptional activator-type NtERFs function together with NtERF3 in the defence response against TMV infection by performing transient ectopic expression, together with gene expression, chromatin immunoprecipitation (ChIP) and promoter analyses. Transient overexpression of NtERF2 and NtERF4 induced cell death in tobacco leaves, albeit later than that induced by NtERF3. Fusion of the EAR motif to the C-terminal end of NtERF2 and NtERF4 abolished their cell death-inducing ability. The expression of NtERF2 and NtERF4 was upregulated at the early phase of N gene-triggered hypersensitive response (HR) against TMV infection. The cell death phenotype induced by overexpression of wild-type NtERF2 and NtERF4 was suppressed by co-expression of an EAR motif-deficient form of NtERF3. Furthermore, ChIP and promoter analyses suggested that NtERF2, NtERF3 and NtERF4 positively or negatively regulate the expression of NtERF3 by binding to its promoter region. Overall, our results revealed the cell death-inducing abilities of genes encoding activator-type NtERFs, including NtERF2 and NtERF4, suggesting that the HR-cell death signalling via the repressor-type NtERF3 is competitively but coordinately regulated by these NtERFs.

Role of the conserved pyridoxal 5'-phosphate-binding protein YggS/PLPBP in vitamin B6 and amino acid homeostasis

The YggS/PLPBP protein (also called COG0325 or PLPHP) is a conserved pyridoxal 5'-phosphate (PLP)-binding protein present in all three domains of life. Recent studies have demonstrated that disruption or mutation of this protein has multifaceted effects in various organisms, including vitamin B6-dependent epilepsy in humans. In Escherichia coli, disruption of this protein-encoded by yggS-perturbs Thr-Ile/Val metabolism, one-carbon metabolism, coenzyme A synthesis, and vitamin B6 homeostasis. This protein is critical for maintaining low levels of pyridoxine 5'-phosphate (PNP) in various organisms. In the yggS-deficient E. coli strain, inhibition of PLP-dependent enzymes, such as the glycine cleavage system by PNP is the root cause of metabolic perturbation. Our data suggest that the YggS/PLPBP protein may be involved in the balancing of B6 vitamers by mediating efficient turnover of protein-bound B6 vitamers. This paper reviews recent findings on the function of the YggS/PLPBP protein.

POS0822 HYPERTROPHIC PACHYMENINGITIS IN ANTINEUTROPHIL CYTOPLASMIC ANTIBODY-ASSOCIATED VASCULITIS: A MULTICENTER SURVEY IN JAPAN

Background

Hypertrophic pachymeningitis (HP), characterized by an inflammatory disorder indicating intracranial or spinal thickening of dura mater, is found to develop as a neurological involvement in antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). Meanwhile, the previous studies focusing on HP in AAV have been reported as a single-institution study, and the analyses were performed in a small number of patients because HP is a rare neurological disorder. Therefore, neither etiological nor clinical characteristics of HP in AAV have been adequately elucidated.

Objectives

This study clarified the characteristics of HP in AAV by analyzing the information of multicenter study in Japan (Japan collaborative registry of ANCA-associated vasculitis: J-CANVAS).

Methods

We analyzed the clinical information from 541 Asian patients with AAV enrolled in J-CANVAS. Of them, newly diagnosed and relapsed AAV were included in 448 and 93, respectively. The epidemiological and clinical findings were compared between patients with and without HP. Clinical manifestations related to AAV were evaluated based on the Birmingham Vasculitis Activity Score version 3. To elucidate independent factors in HP development, logistic regression analyses were additionally performed.

Results

Of the total 541 patients (mean age: 71±14 years, M:F = 1:1.2), HP was demonstrated in 28 (5.17%), including 17 (3.79%) in newly diagnosed AAV and 11 (11.8%) in relapsed AAV. The classification of granulomatosis with polyangiitis (GPA) was significantly higher in patients with HP than those without HP (50% vs. 21%, p = 0.0007). In newly diagnosed AAV, patients with HP significantly had higher GPA classification and higher positivity for PR3-ANCA than those without HP (53% vs. 17%, p = 0.001; 29% vs. 9%, p = 0.015, respectively). Conversely, positivity for MPO-ANCA was significantly higher in patients with HP than those without HP in relapsed AAV (91% vs. 55%, p = 0.025), despite not significantly different in the classification of AAV. Headache and cranial neuropathies were significant neurological symptoms in patients with HP compared to those without HP (82% vs. 6.6%, p < 0.0001; 32% vs. 2.9%, p < 0.0001, respectively). Besides, ear, nose and throat (ENT) and mucous membranes/eyes were significantly higher involvements in patients with HP than in those without HP (54% vs. 26%, p = 0.003; 29% vs. 9%, p = 0.003, respectively). Moreover, higher complications of “conjunctive hearing loss” and “sudden visual loss”, which are included in the categories of ENT and mucous membranes/eyes involvement, respectively, were significantly indicated in patients with HP than those without HP (39% vs. 7.2%, p < 0.0001; 21% vs. 1.2%, p < 0.0001, respectively). Multivariable logistic regression analysis identified that ENT (odds ratio [OR] 1.28, 95% confident interval [CI] 1.09 to 1.49, p = 0.002) and mucous membranes/eyes involvement (OR 1.37, CI 1.14 to 1.65, p = 0.0006), as well as conjunctive hearing loss (OR 4.52, CI 1.56 to 13.05, p = 0.005) and sudden visual loss (OR 1.84, CI 1.12 to 3.00, p = 0.015), were independent related factors in patients with HP.

Conclusion

GPA could be significantly classified in patients with HP. Notably, patients with HP significantly showed higher positivity for PR3-ANCA than those without HP in newly diagnosed AAV. Furthermore, sudden visual loss and conjunctive hearing loss might be implicated in HP development.

Disclosure of Interests

None declared

AB0625 Association between Cytomegalovirus Reactivation and Renal Prognosis during Remission Induction Therapy for ANCA-Associated Vasculitis

Background

Cytomegalovirus (CMV) has been associated with atherosclerosis in patients with chronic renal failure, and may cause secondary nephrotic syndrome. Therefore, we hypothesized that the reactivation of CMV by immunosuppressive therapy in patients with vasculitis may affect renal function.

Objectives

The purpose of this study was to investigate relationships between CMV infection and renal function during ANCA-associated vasculitis remission induction therapy.

Methods

This retrospective cohort study enrolled microscopic polyangiitis (MPA), granulomatosis with polyangiitis (GPA), and eosinophilic granulomatosis with polyangiitis patients at 25 sites in Japan who had a first or severe relapse between January 2017 and June 2020. Of these, patients with MPA or GPA who had a positive renal lesion score on BVAS (version 3) at baseline, or vasculitis findings on renal biopsy, CMV assayed by 48 weeks of treatment, were included. Patients were divided into two groups based on the presence or absence of a positive CMV antigen test during the remission induction phase (0–48 weeks of treatment). Outcomes were the rate of change in estimated glomerular filtration rate (eGFR) at 48 weeks after initiation of treatment in both groups, as determined by (eGFR at 48 weeks - eGFR at the initiation of treatment)/eGFR at the initiation of treatment; where lower values were associated with worse renal function. General linear models adjusted for age, gender, presence of diabetes or chronic kidney disease, and the use of rituximab or cyclophosphamide were generated.

Results

A total of 387 patients had CMV antigen measured during ANCA-associated vasculitis treatment, of which 164 had renal involvement and eGFR measured at 48 weeks. Seventy-seven (47.0%) were male and the median age was 75 years (range 69–80 years). CMV reactivation was observed in 44 patients (26.8%). The beta coefficient of multiple regression analysis with CMV positive as 1 and negative as 0 was 0.08 (95% confidence interval -0.13 to 0.29) (p = 0.47). The rate of change in eGFR was higher in the CMV positive group, but not statistically significantly.

Conclusion

Contrary to our hypothesis, renal prognoses tended to be better when CMV reactivation was observed. The patients in the CMV reactivation group may have been treated more aggressively, and some patients with a poor prognosis who were not followed up for 48 weeks dropped out. Further research investigating the adjustment of treatment methods is required.

Disclosure of Interests

None declared

POS0247 GLUCOCORTICOID TAPERING STRATEGY FOR ANCA-ASSOCIATED VASCULITIS: ADDRESSING THE GAP BETWEEN RECOMMENDATIONS AND REAL-WORLD PRACTICE

Background

Antineutrophil cytoplasmic antibody -associated vasculitis (AAV) is usually treated with combination of high-dose glucocorticoid (GC) and immunosuppressive agents, followed by tapering GC dose. Although the European League Against Rheumatism (EULAR) has specific recommendations for tapering the GC dose, clinicians often taper it slower than recommended due to concerns of potential disease relapse. However, such slower taper may prolong GC exposure for the patients, increasing the risk of adverse events, particularly infection.

Objectives

The aims of our study were (1) to clarify GC dose tapering in the treatment of AAV in a real-world setting, in contrast to the EULAR recommendation of 2015 and (2) to compare the incidence of AAV relapse and severe infection between patients underdoing EULAR-recommended tapering and those undergoing slower tapering than the recommendation.

Methods

In this multicenter (25 sites in Japan), observational, retrospective study of AAV, 541 patients who had initial or severe relapse were enrolled between January 2017 and June 2020. Of these, 349 patients with microscopic polyangiitis (MPA) or granulomatosis with polyangiitis (GPA) who entered in GC tapering phase after successful induction treatment were included. These patients were then grouped on the pace of GC tapering, defined as the GC dose at 12 weeks after treatment initiation: (1) EULAR group: 7.5-10 mg/day of GC, according to the EULAR recommendation of 2015, and (2) SLOWER group: >10 mg/day of GC. Their baseline characteristics and clinical outcomes were compared. Primary outcome was defined as relapse-free days from treatment initiation, whereas secondary outcome included the incidence of infectious events requiring hospitalization within 48 weeks from treatment initiation. Multivariable analysis was performed to assess the relationship between tapering pace and clinical outcomes.

Results

There were 44 patients (12.6%) in the EULAR group and 290 (83.2%) in the SLOWER group. Regarding baseline characteristics, compared with the EULAR group, the SLOWER group had significantly higher serum C-reactive protein level (EULAR, 5.89 ± 6.89 mg/dL vs SLOWER, 7.56 ± 6.01 mg/dL; p = 0.03), as well as a trend toward higher Birmingham Vasculitis Activity Score (version 3) (EULAR, 11.80 ± 7.01 SLOWER, 13.93 ± 7.06; p = 0.08) We did not observe any significant differences in the frequency of relapses between the two groups (EULAR, 8/44, 18.2% vs SLOWER, 55/290, 19.0%; p = 0.63). Multivariable Cox proportional hazard analysis revealed no relationship GC dose at 12 weeks from treatment initiation and incidence of relapse. However, upon logistic regression analysis, the SLOWER group was found to have significant higher risk of a severe infectious event within 48 weeks from treatment initiation (p = 0.046; hazard ratio, 1.27; 95% confidence interval, 1.004 – 1.601).

Conclusion

Our finding indicates that clinicians tended to taper GC slower for patients with higher disease activity. However, slower GC taper was not found to reduce the frequency of relapse. In addition, slower GC taper was found to increase the risk of a severe infection. Hence, clinicians should pay attention not only relapsing but also late GC taper resulting in the risk of serious infection, especially in patients with higher disease activity of AAV.

References

[1]Eur J Clin Invest 2015;45 (3): 346–368.

[2]Rheumatology (Oxford). 2021 Dec 24;61(1):205-212.

[3]Arthritis Res Ther. 2021 Mar 20;23(1):90.

[4]Scand J Rheumatol. 2022 Jan 20;1-13.

[5]J Rheumatol. 2018 Apr;45(4):521-528.

[6]Rheumatol Adv Pract. 2021 Mar 9;5(3):rkab018.

[7]Ann Rheum Dis. 2016 Sep;75(9):1583-94.

Figure 1.

Acknowledgements

We would like to thank Editage (www.editage.com) for English language editing.

Disclosure of Interests

None declared

Identification and characterization of a serine racemase in the silkworm Bombyx mori

The pupae of lepidopterans contain high concentrations of endogenous d-serine. In the silkworm Bombyx mori, d-serine is negligible during the larval stage but increases markedly during the pupal stage, reaching 50% of the total free serine. However, the physiological function of d-serine and the enzyme responsible for its production are unknown. Herein, we identified a new type of pyridoxal 5'-phosphate (PLP)-dependent serine racemase (SR) that catalyzes the racemization of l-serine to d-serine in B. mori. This silkworm SR (BmSR) has an N-terminal PLP-binding domain that is homologous to mammalian SR and a C-terminal putative ligand-binding regulatory-like domain (ACT-like domain) that is absent in mammalian SR. Similar to mammalian SRs, BmSR catalyzes the racemization and dehydration of both serine isomers. However, BmSR is different from mammalian SRs as evidenced by its insensitivity to Mg2+/Ca2+ and Mg-ATP-which are required for activation of mammalian SRs-and high d-serine dehydration activity. At the pupal stage, the SR activity was predominantly detected in the fat body, which was consistent with the timing and localization of BmSR expression. The results are an important first step in elucidating the physiological significance of d-serine in lepidopterans.

Quantum device designing (QDD) for future semiconductor engineering

In semiconductor device history, a trend is observed where narrowing and increasing the number of material layers improve device functionality, with diodes, transistors, thyristors, and superlattices following this trend. While superlattices promise unique functionality, they are not widely adopted due to a technology barrier, requiring advanced fabrication, such as molecular beam epitaxy and lattice-matched materials. Here, a method to design quantum devices using amorphous materials and physical vapor deposition is presented. It is shown that the multiplication gain M depends on the number of layers of the superlattice, N, as M = kN, with k as a factor indicating the efficiency of multiplication. This M is, however, a trade-off with transit time, which also depends on N. To demonstrate, photodetector devices are fabricated on Si, with the superlattice of Se and As₂Se₃, and characterized using current-voltage (I-V) and current-time (I-T) measurements. For superlattices with the total layer thicknesses of 200 nm and 2 μm, the results show that k_200nm = 0.916 and k_2μm = 0.384, respectively. The results confirm that the multiplication factor is related to the number of superlattice layers, showing the effectiveness of the design approach.

Identification and biochemical characterization of a heteromeric cis-prenyltransferase from the thermophilic archaeon Archaeoglobus fulgidus

cis-Prenyltransferases (cPTs) form linear polyprenyl pyrophosphates, the precursors of polyprenyl or dolichyl phosphates that are essential for cell function in all living organisms. Polyprenyl phosphate serves as a sugar-carrier for pesptidoglycan cell wall synthesis in bacteria, a role which dolichyl phosphate performs analogously for protein glycosylation in eukaryotes and archaea. Bacterial cPTs are characterized by their homodimeric structure, while cPTs from eukaryotes usually require two distantly homologous subunits for enzymatic activity. This study identifies the subunits of heteromeric cPT, Af1219 and Af0707, from a thermophilic sulfur-reducing archaeon, Archaeoglobus fulgidus. Both subunits are indispensable for cPT activity, and their protein-protein interactions were demonstrated by a pulldown assay. Gel filtration chromatography and chemical cross-linking experiments suggest that Af1219 and Af0707 likely form a heterotetramer complex. Although this expected subunit composition agrees with a reported heterotetrameric structure of human hCIT/NgBR cPT complex, the similarity of the quaternary structures is likely a result of convergent evolution.

Isopentenyl diphosphate/dimethylallyl diphosphate-specific Nudix hydrolase from the methanogenic archaeon Methanosarcina mazei

Nudix hydrolases typically catalyze the hydrolysis of nucleoside diphosphate linked to moiety X and yield nucleoside monophosphate and X-phosphate, while some of them hydrolyze a terminal diphosphate group of non-nucleosidic compounds and convert it into a phosphate group. Although the number of Nudix hydrolases is usually limited in archaea comparing with those in bacteria and eukaryotes, the physiological functions of most archaeal Nudix hydrolases remain unknown. In this study, a Nudix hydrolase family protein, MM_2582, from the methanogenic archaeon Methanosarcina mazei was recombinantly expressed in Escherichia coli, purified, and characterized. This recombinant protein shows higher hydrolase activity toward isopentenyl diphosphate and short-chain prenyl diphosphates than that toward nucleosidic compounds. Kinetic studies demonstrated that the archaeal enzyme prefers isopentenyl diphosphate and dimethylallyl diphosphate, which suggests its role in the biosynthesis of prenylated flavin mononucleotide, a recently discovered coenzyme that is required, for example, in the archaea-specific modified mevalonate pathway.

Exercise-induced hypercalcemia and vasopressin-mediated bone resorption

Our human observational study showed that elevated arginine vasopressin levels by heavy exercise, not catecholamines, were associated with elevated serum tartrate-resistant acid phosphatase 5b (TRACP-5b). The increase in serum calcium was positively associated with percent changes of TRACP-5b, implying the involvement of bone resorption in the pathogenesis of exercise-induced hypercalcemia.

INTRODUCTION

It remains unclear whether enhanced bone resorption explains exercise-induced hypercalcemia. An experimental study demonstrated that arginine vasopressin (AVP) stimulated osteoclast activity.

METHODS

We conducted a prospective observational study, enrolling 65 trained healthy male officers of the Japan Self-Defense Forces (34 and 31 in waves 1 and 2, respectively). Before and after a 5-h heavy exercise, we collected laboratory data including bone markers, symptoms, and ionized calcium (iCa; wave 2 only). As blood calcium levels change after exercise, we estimated calcium (corrected calcium) levels immediately after the exercise using the correlation between blood calcium and time from the end of exercise in another cohort.

RESULTS

Body weight decreased by 6.9% after the exercise. Corrected post-exercise serum total calcium (tCa) and iCa levels were significantly higher than pre-exercise levels, and 18% of participants showed hypercalcemia defined as corrected tCa >10.4 mg/dL or iCa >1.30 mmol/L. Serum tartrate-resistant acid phosphatase 5b (TRACP-5b), plasma three fractions of catecholamines, and AVP elevated significantly (median 14.3 pg/mL), while procollagen type 1 N-terminal propeptide and whole parathyroid hormone showed significant decreases. Corrected tCa increase showed a non-linear positive association with percent changes of TRACP-5b (%ΔTRACP-5b) even after adjustment for confounders. In addition, %ΔTRACP-5b was not associated with catecholamines, but with post-exercise AVP levels after adjustment for pre-exercise TRACP-5b. Symptoms of nausea or vomiting (observed in 20%) were positively associated with corrected post-exercise iCa after adjustment for post-exercise blood pH.

CONCLUSION

AVP elevation may explain bone resorption and the following hypercalcemia in the setting of heavy exercise.

Estimation of genetic parameter for feed efficiency and resilience traits in three pig breeds

Recently, automatic feeders have become popular for collecting daily feed intake data in the pig industry, making it possible to evaluate genetic effects on feed efficiency and resilience traits, expressed as day-to-day fluctuations in feeding records. This study aimed to understand the influence of genetic factors on feed efficiency traits, including residual intake and BW gain (RIG), and resilience traits, as well as to compare the differences in genetic parameter estimates among three purebred pig breeds. A total of 6 103 pigs from three breeds (Large White: 1 193 pigs, Landrace: 3 010 pigs, and Duroc: 1 900 pigs) were raised in a specific pathogen-free environment. The growth and feed intake records during the testing period were obtained using automatic feeders, and the average daily gain (ADG) and average feed intake (AFI) were calculated. Feed conversion ratio (FCR), residual feed intake (RFI), residual gain, and RIG were calculated as feed efficiency traits, and the log-transformed variance of deviation for the daily feed intake (LnVar_FI), daily occupation time (LnVar_OC), and the daily number of visits to the feeder (LnVar_VT) was calculated as resilience traits. After estimating the genetic parameters for each breed, a meta-analysis was performed to obtain the weighted mean of heritability estimates (h_m²) and genetic correlation estimates (GC_m) for the three breeds. The h_m² were moderate and ranged from 0.31 to 0.39 for feed efficiency traits and 0.31 to 0.40 for resilience traits, and there were no significant differences in heritability estimates among the three breeds except for AFI, RFI, and RIG. For feed efficiency traits, the FCR and RIG showed favourably moderate GC_m with AFI (0.29 and -0.33, respectively) and ADG (-0.39 and 0.31, respectively). For resilience traits, the LnVar_FI and LnVar_VT showed favourably low to moderate GC_m with FCR (0.33 and 0.28, respectively) and RIG (-0.37 and 0.28, respectively), and there were no genetic relationships of LnVar_OC with FCR and RIG (the absolute value of GC_m was 0.01). There was no significant difference in the genetic correlation estimates among the three breeds for feed efficiency and resilience traits. Our results suggest that feed efficiency and resilience traits were heritable, and resilience traits showed favourable or no genetic correlation with feed efficiency traits. In addition, the influence of genetic factors on feed efficiency and resilience traits could be the same among breeds.

Design of microfluidic channels to prevent negative filtration in implantable hemofiltration devices

In order to improve the quality of life of dialysis patients, our group have been developing an implantable hemofiltration device (IHFD) composed of multiple layers of dialysis membranes and microfluidic channels. To improve the hemodialysis performance of IHFD, preventing the negative filtration, which is caused by the oncotic pressure of blood, is mandatory. In this study, we fabricated IHFDs with five different microchannel designs and experimentally investigated the performance of each device in in vitro experiment. In addition, the successful IHFD was further evaluated by ex vivo experiments with a beagle dog. The experiments verified the effectiveness of the microchannel design, which will be used for the IHFD for in vivo experiments with pigs in the future.

Major hepatectomy with combined vascular resection for perihilar cholangiocarcinoma

Background

Hepatectomy with vascular resection (VR) for perihilar cholangiocarcinoma (PHCC) is a challenging procedure. However, only a few reports on this procedure have been published and its clinical significance has not been fully evaluated.

Methods

Patients undergoing surgical resection for PHCC from 2002–2017 were studied. The surgical outcomes of VR and non-VR groups were compared.

Results

Some 238 patients were included. VR was performed in 85 patients. The resected vessels were hepatic artery alone (31 patients), portal vein alone (37 patients) or both (17 patients). The morbidity rates were almost the same in the VR (49.4 per cent) and non-VR (43.8 per cent) groups (P = 0.404). The mortality rates of VR (3.5 per cent) and non-VR (3.3 per cent) were also comparable (P > 0.999). The median survival time (MST) was 45 months in the non-VR group and 36 months in VR group (P = 0.124). Among patients in whom tumour involvement was suspected on preoperative imaging and whose carbohydrate antigen 19-9 (CA19-9) value was 37 U/ml or less, MST in the VR group was significantly longer than that in the non-VR group (50 versus 34 months, P = 0.017). In contrast, when the CA19-9 value was greater than 37 U/ml, MST of the VR and non-VR groups was comparable (28 versus 29 months, P = 0.520).

Conclusion

Hepatectomy with VR for PHCC can be performed in a highly specialized hepatobiliary centre with equivalent short- and long-term outcomes to hepatectomy without VR.

Efficacy and safety of mogamulizumab by patient baseline blood tumour burden: a post hoc analysis of the MAVORIC trial

Background

Mogamulizumab was compared with vorinostat in the phase 3 MAVORIC trial (NCT01728805) in 372 patients with relapsed/refractory mycosis fungoides (MF) or Sézary syndrome (SS) who had failed ≥1 prior systemic therapy. Mogamulizumab significantly prolonged progression‐free survival (PFS), with a superior objective response rate (ORR) vs. vorinostat.

Objectives

This post hoc analysis was performed to evaluate the effect of baseline blood tumour burden on patient response to mogamulizumab.

Methods

PFS, ORR, time to next treatment (TTNT), skin response (modified Severity‐Weighted Assessment Tool [mSWAT]) and safety were assessed in patients stratified by blood classification (B0 [n = 126], B1 [n = 62], or B2 [n = 184], indicating increasing blood involvement).

Results

Investigator‐assessed PFS was longer for mogamulizumab versus vorinostat across all blood classes, significantly so for B1 and B2 patients. ORR was higher with mogamulizumab than with vorinostat in all blood classification groups and more markedly so with escalating B class (B0: 15.6% vs. 6.5%, P = 0.0549; B1: 25.8% vs. 6.5%, P = 0.2758; B2: 37.4% vs. 3.2%, P < 0.0001). TTNT was significantly longer for patients treated with mogamulizumab versus vorinostat with B1 (12.63 vs. 3.07 months; HR 0.32 [95% CI 0.16–0.67]; P = 0.0018) and B2 (13.07 vs. 3.53 months; HR 0.30 [95% CI 0.21–0.43]; P < 0.0001) blood involvement. In the mogamulizumab arm, 81 patients (43.5%) had ≥50% change in the mSWAT vs. 41 patients (22.0%) with vorinostat; mSWAT improvements with mogamulizumab occurred most often in B1 and B2 patients. Rapid, sustained reductions were seen in CD4⁺CD26^‐ cell counts and CD4:CD8 ratios in mogamulizumab patients for all B classes. Treatment‐emergent adverse events were less frequent overall with mogamulizumab and similar in frequency regardless of B class.

Conclusions

This post hoc analysis indicates greater clinical benefit with mogamulizumab vs. vorinostat in patients with MF and SS classified as having B1 and B2 blood involvement.

AB0763 IGG4-RELATED CORONARY PERIARTERITIS: SYSTEMATIC LITERATURE REVIEW WITH OUR CASE SERIES

Background:

Coronary periarteritis is one of the clinical manifestations of IgG4-related disease. It can cause serious conditions such as angina and ruptured aneurysms. Therefore, it is important to recognize the clinical and radiological characteristics, which was little known.

Objectives:

We report four patients with IgG4-related coronary periarteritis with a systematic literature review.

Methods:

We identified four patients with IgG4-related coronary periarteritis at the St. Luke’s International Hospital in Tokyo, Japan from 2014 to 2020. A systematic literature review was conducted for English articles on IgG4-related coronary periarteritis cases with a full text or abstract available. We summarized patient demographics, IgG and IgG4 titers, the site and morphological type of coronary lesion, and other organ involvements.

Results:

Our 4 cases and 38 cases identified by the literature review were assessed. Coronary artery lesions were detected by a coronary CT in all but two cases. Wall thickening was the most common type of the lesion. Moreover, there were 32 (76.1%) patients with other organ involvements. The commonest other lesion was peri-aortitis in 21 (50.0%) patients. In cases with peri-aortitis, IgG and IgG4 titers were significantly higher than those without peri-aortitis (IgG4; 1540 [705.0, 2570.0] vs 246.0 [160.0, 536.3]; p = 0.001, IgG; 3596.5 [2838.3, 4260.0] vs 1779.0 [1288.3, 1992.8]; p =0.040). In addition, 15 (71.4%) patients of them had three or more IgG4 related organ involvements.

Conclusion:

Coronary CT was a useful imaging modality for the diagnosis of IgG4-related coronary periarteritis, and wall thickening was the most common lesion. Moreover, about half cases coexisted with peri-aortitis. Peri-aortitis and other organ involvements should be screened in those with higher IgG and IgG4.

Table 1.

Characteristics of our cases and the literature review cases.

RCA: right coronary artery, LAD: left anterior descending artery, LCx: left circumflex artery

Disclosure of Interests:

None declared

Utility of remnant liver volume for predicting posthepatectomy liver failure after hepatectomy with extrahepatic bile duct resection

BACKGROUND

Hepatectomy with extrahepatic bile duct resection is associated with a high risk of posthepatectomy liver failure (PHLF). However, the utility of the remnant liver volume (RLV) in cholangiocarcinoma has not been studied intensively.

METHODS

Patients who underwent major hepatectomy with extrahepatic bile duct resection between 2002 and 2018 were reviewed. The RLV was divided by body surface area (BSA) to normalize individual physical differences. Risk factors for clinically relevant PHLF were evaluated with special reference to the RLV/BSA.

RESULTS

A total of 289 patients were included. The optimal cut-off value for RLV/BSA was determined to be 300 ml/m2. Thirty-two patients (11.1 per cent) developed PHLF. PHLF was more frequent in patients with an RLV/BSA below 300 ml/m2 than in those with a value of 300 ml/m2 or greater: 19 of 87 (22 per cent) versus 13 of 202 (6.4 per cent) (P < 0.001). In multivariable analysis, RLV/BSA below 300 ml/m2 (P = 0.013), future liver remnant plasma clearance rate of indocyanine green less than 0.075 (P = 0.031), and serum albumin level below 3.5 g/dl (P = 0.015) were identified as independent risk factors for PHLF. Based on these risk factors, patients were classified into three subgroups with low (no factors), moderate (1-2 factors), and high (3 factors) risk of PHLF, with PHLF rates of 1.8, 14.8 and 63 per cent respectively (P < 0.001).

CONCLUSION

An RLV/BSA of 300 ml/m2 is a simple predictor of PHLF in patients undergoing hepatectomy with extrahepatic bile duct resection.

Changes in nutritional status by recovery phase interventions would be a powerful determinant of cardiovascular prognosis in heart failure patients

Background

Adequate nutrition has been proposed for better cardiovascular prognosis as well as fitness, although the impact of the “changes” in nutrition and fitness at recovery phase on the future prognosis has been unclear.

Purpose

We aimed to examine whether the change in nutritional level as a result of dietary intervention combined with exercise would determine patients' cardiovascular prognosis.

Methods

This study involved 398 consecutive patients who participated in phase II comprehensive cardiac rehabilitation (CCR) for at least three months. All patients underwent cardiopulmonary exercise test (CPX) at the initial and completion periods of CCR. Individual dietary guidance was periodically performed with exercise. Peak oxygen uptake (PVO2) was measured through CPX to evaluate the fitness level, whereas nutritional status was evaluated using the geriatric nutritional risk index (GNRI). Patients were divided in two groups according to the baseline GNRI and the change in GNRI (ΔGNRI) by the median, respectively, to compare their prognosis between groups. Then they were classified into four categories according to the median values of the changes in GNRI (ΔGNRI) and PVO2 (ΔPVO2) during CCR: “Both improved”, “Only GNRI improved”, “Only PVO2 improved” and “Both NOT improved”, to compare MACCE-free rate between categories.

Results

The rate of MACCE showed significant difference between categories (14%, 18%, 19% and 36%, p&lt;0.001), which was approximately 2 times higher in “Both NOT improved” than the others. Kaplan-Meier analysis showed that according to the level of ΔGNRI, “higher ΔGNRI group” showed significantly higher in MACCE-free survival rate than “lower ΔGNRI group” (log rank p=0.010), whereas there was no significant difference according to the baseline GNRI (see figure). According to the categories divided by ΔGNRI and ΔPVO2, MACCE-free rate was significantly lower in “Both NOT improved” (log rank p&lt;0.001) compared to the other categories. Cox proportional hazard regression analysis revealed that “both NOT improved” was an independent predictor of MACCE (hazard ratio, 2.1, 95% confident interval, 1.344–3.175, p&lt;0.001).

Conclusion

Changes in nutritional level would determine patients' cardiovascular prognosis rather than the baseline nutritional level. Non-responders who showed no improvement in nutritional or fitness by interventions may result in a poor cardiovascular outcome.

Funding Acknowledgement

Type of funding source: None

Differences between primary care physicians and specialised neurotologists in the diagnosis of dizziness and vertigo in Japan

OBJECTIVE

Vertigo and dizziness are frequent symptoms in patients at out-patient services. An accurate diagnosis for vertigo or dizziness is essential for symptom relief; however, it is often challenging. This study aimed to identify differences in diagnoses between primary-care physicians and specialised neurotologists.

METHOD

In total, 217 patients were enrolled. To compare diagnoses, data was collected from the reference letters of primary-care physicians, medical questionnaires completed by patients and medical records.

RESULTS

In total, 62.2 per cent and 29.5 per cent of the patients were referred by otorhinolaryngologists and internists, respectively. The cause of vertigo or dizziness and diagnosis was missing in 47.0 per cent of the reference letters. In addition, 67.3 per cent of the diagnoses by previous physicians differed from those reported by specialised neurotologists.

CONCLUSION

To ensure patient satisfaction and high quality of life, an accurate diagnosis for vertigo or dizziness is required; therefore, methods or materials to improve the diagnostic accuracy are needed.