Cumulative antibiogram preparation among hospitals participating in the Japan Surveillance for Infection Prevention and Healthcare Epidemiology

BACKGROUND

The cumulative antibiogram is essential to guide empirical therapy for infectious diseases and monitor the trend of antimicrobial resistance. However, the status of antibiogram generation at medical institutions in Japan is uncertain.

METHODS

A web-based questionnaire survey was conducted in February 2023 on the status of antibiogram preparation among facilities participating in the Japan Surveillance for Infection Prevention and Healthcare Epidemiology (J-SIPHE), an infection control surveillance system in Japan.

RESULTS

The questionnaire collection rate was 19.6% (379/1931). Of all facilities, 47% (178/379) performed microbiological tests mainly in-house, while 53% (201/379) performed microbiological tests mainly outsourced. Of all facilities, 78% (296/379) prepared antibiograms. Of those without antibiograms, 33% (27/83) were considering the development in the future. Some facilities cited staff shortage as a barrier to preparing antibiograms. Of the 214 facilities with antibiograms that could use the J-SIPHE system to prepare antibiograms, 19% (41/214) were using the J-SIPHE system to prepare their antibiograms.

CONCLUSIONS

One-quarter of the facilities that responded to the survey had not prepared antibiograms. Technical support for surveillance and awareness activity for using cumulative antibiograms might promote antibiogram preparation in Japan, which may improve antimicrobial stewardship and antimicrobial resistance measures.

Metabolic Potential of the Superphylum Patescibacteria Reconstructed from Activated Sludge Samples from a Municipal Wastewater Treatment Plant

Patescibacteria are widely distributed in various environments and often detected in activated sludge. However, limited information is currently available on their phylogeny, morphology, and ecophysiological role in activated sludge or interactions with other microorganisms. In the present study, we identified microorganisms that interacted with Patescibacteria in activated sludge via a correlation ana-lysis using the 16S rRNA gene, and predicted the metabolic potential of Patescibacteria using a metagenomic ana-lysis. The metagenome-assembled genomes of Patescibacteria consisted of three Saccharimonadia, three Parcubacteria, and one Gracilibacteria, and showed a strong positive correlation of relative abundance with Chitinophagales. Metabolic predictions from ten recovered patescibacterial and five Chitinophagales metagenome-assembled genomes supported mutualistic interactions between a member of Saccharimonadia and Chitinophagales via N-acetylglucosamine, between a member of Parcubacteria and Chitinophagales via nitrogen compounds related to denitrification, and between Gracilibacteria and Chitinophagales via phospholipids in activated sludge. The present results indicate that various interactions between Patescibacteria and Chitinophagales are important for the survival of Patescibacteria in activated sludge ecosystems.

Growth of nitrite-oxidizing Nitrospira and ammonia-oxidizing Nitrosomonas in marine recirculating trickling biofilter reactors

Aerobic ammonia and nitrite oxidation reactions are fundamental biogeochemical reactions contributing to the global nitrogen cycle. Although aerobic nitrite oxidation yields 4.8-folds less Gibbs free energy (∆G_r ) than aerobic ammonia oxidation in the NH₄ ⁺ -feeding marine recirculating trickling biofilter reactors operated in the present study, nitrite-oxidizing and not ammonia-oxidizing Nitrospira (sublineage IV) outnumbered ammonia-oxidizing Nitrosomonas (relative abundance; 53.8% and 7.59% respectively). CO₂ assimilation efficiencies during ammonia or nitrite oxidation were 0.077 μmol-¹⁴ CO₂ /μmol-NH₃ and 0.053-0.054 μmol-¹⁴ CO₂ /μmol-NO₂ ^- respectively, and the difference between ammonia and nitrite oxidation was much smaller than the difference of ∆G_r . Free-energy efficiency of nitrite oxidation was higher than ammonia oxidation (31%-32% and 13% respectively), and high CO₂ assimilation and free-energy efficiencies were a determinant for the dominance of Nitrospira over Nitrosomonas. Washout of Nitrospira and Nitrosomonas from the trickling biofilter reactors was also examined by quantitative PCR assay. Normalized copy numbers of Nitrosomonas amoA were 1.5- to 1.7-folds greater than Nitrospira nxrB and 16S rRNA gene in the reactor effluents. Nitrosomonas was more susceptible for washout than Nitrospira in the trickling biofilter reactors, which was another determinant for the dominance of Nitrospira in the trickling biofilter reactors.

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.

A single-center descriptive study of untraced sources of infection among new cases of coronavirus disease in Tokyo, Japan

We investigated possible sources of newly infected patients with coronavirus disease (COVID-19) after the fourth wave in order to explore unknown sources. Retrospective chart review on all the confirmed patients with COVID-19 admitted to the National Center for Global Health and Medicine (NCGM) in Tokyo, Japan was conducted from May 22 through June 29, 2021. Among the 22 participants, 14 (64%) had a history of known high-risk infection behaviors. Of those, 12 reported that their activities involved eating and drinking. In addition, there were 24 high-risk situations, of those, 21 (88%) were related to indoor dining, and masks were not worn in 22 situations (92%). New source of infection has not been identified. In situations with a high known risk of infection, many cases were related to eating and drinking, and insufficient use of masks was evident. Raising risk awareness on infection prevention and control of COVID-19 is urgently needed.

Tb3+-doped fluorescent glass for biology

Optical investigation and manipulation constitute the core of biological experiments. Here, we introduce a new borosilicate glass material that contains the rare-earth ion terbium(III) (Tb³⁺), which emits green fluorescence upon blue light excitation, similar to green fluorescent protein (GFP), and thus is widely compatible with conventional biological research environments. Micropipettes made of Tb³⁺-doped glass allowed us to target GFP-labeled cells for single-cell electroporation, single-cell transcriptome analysis (Patch-seq), and patch-clamp recording under real-time fluorescence microscopic control. The glass also exhibited potent third harmonic generation upon infrared laser excitation and was usable for online optical targeting of fluorescently labeled neurons in the in vivo neocortex. Thus, Tb³⁺-doped glass simplifies many procedures in biological experiments.

Visually cued fear conditioning test for memory impairment related to cortical function

AIM

Fear conditioning tests are intended to elucidate a subject's ability to associate a conditioned stimulus with an aversive, unconditioned stimulus, such as footshock. Among these tests, a paradigm related to precise cortical functions would be increasingly important in drug screening for disorders such as schizophrenia and dementia. Therefore, we established a new fear conditioning paradigm using a visual cue in mice. In addition, the validity of the test was evaluated using a genetically engineered mouse, heterozygous deficient in Mdga1 (Mdga1+/-), which is related to schizophrenia.

RESULTS

Mice were given footshocks associated with a visual cue of moving gratings at training in 25-minute sessions. The mice showed the conditioned response of freezing behavior to the visual stimulus at testing 24 hours after the footshocks. In the test for validation, the Mdga1+/- deficient mice showed significantly less freezing than wild-type mice.

CONCLUSION

The visually cued fear conditioning paradigm with moving gratings has been established, which is experimentally useful to evaluate animal cortical functions. The validity of the test was confirmed for Mdga1-deficient mice with possible deficiency in cortical functions.

Clinical epidemiology of hospitalized patients with COVID-19 in Japan: Report of the COVID-19 REGISTRY JAPAN

Background

There is limited understanding of the characteristics of patients with coronavirus disease 2019 (COVID-19) requiring hospitalization in Japan.

Methods

This study included 2638 cases enrolled from 227 healthcare facilities that participated in the COVID-19 Registry Japan (COVIREGI-JP). The inclusion criteria for enrollment of a case in COVIREGI-JP are both (1) a positive severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) test and (2) inpatient treatment at a healthcare facility.

Results

The median age of hospitalized patients with COVID-19 was 56 years (interquartile range [IQR], 40–71 years). More than half of cases were male (58.9%, 1542/2619). Nearly 60% of the cases had close contact to confirmed or suspected cases of COVID-19. The median duration of symptoms before admission was 7 days (IQR, 4–10 days). The most common comorbidities were hypertension (15%, 396/2638) and diabetes without complications (14.2%, 374/2638). The number of nonsevere cases (68.2%, n = 1798) was twice the number of severe cases (31.8%, n = 840) at admission. The respiratory support during hospitalization includes those who received no oxygen support (61.6%, 1623/2636) followed by those who received supplemental oxygen (29.9%, 788/2636) and invasive mechanical ventilation/extracorporeal membrane oxygenation (8.5%, 225/2636). Overall, 66.9% (1762/2634) of patients were discharged home, while 7.5% (197/2634) died.

Conclusions

We identified the clinical epidemiological features of COVID-19 in hospitalized patients in Japan. When compared with existing inpatient studies in other countries, these results demonstrated fewer comorbidities and a trend towards lower mortality.

Preferences for health information in middle-aged Japanese workers based on health literacy levels: a descriptive study

OBJECTIVES

To describe the health information preferences in middle-aged Japanese workers based on health literacy (HL) levels and presence of medications.

STUDY DESIGN

A cross-sectional study.

METHODS

We performed a web-based questionnaire survey with Japanese workers aged below 60 years. HL was assessed using the total score of communicative skills (five items) and critical skills (four items) from the 14-item Health Literacy Scale. Regarding their health information preferences, participants were asked about the health information they wanted (four items), could easily understand (six items), or easily use (two items) and answered on a 4-point scale (strongly agree/agree/disagree/strongly disagree). The percentages of the affirmative responses (strongly agree or agree) were compared among tertiles based on the HL score.

RESULTS

We obtained data from a total of 3387 volunteers, of whom 510 participants were on either antihypertensive, lipid-lowering, or antidiabetic drugs. Compared with the high HL and middle HL groups, low HL had fewer affirmative responses to most health information items. Health information items received 70% of affirmative responses even in the low HL level. They were visually shown by figures or pictures, highlighted by colors for important points, could be read in 1-2 min, and were accessed on the Internet, regardless of the presence of medications. Additionally, the explanation for mechanisms of medications or lifestyle to prevent or improve diseases showed high affinity in all HL levels, only for those on medications.

CONCLUSIONS

This result generates a hypothesis that low HL individuals have a low interest in health information. Our data showed several possible forms of health information with high affinity based on HL levels that would help plan future population approaches.

Peripheral administration of κ-opioid receptor antagonist stimulates gonadotropin-releasing hormone pulse generator activity in ovariectomized, estrogen-treated female goats

Pulsatile gonadotropin-releasing hormone (GnRH) secretion is indispensable for reproduction in mammals. Kisspeptin neurons in the hypothalamic arcuate nucleus (ARC), referred to as KNDy neurons because of the coexpression of neurokinin B and dynorphin A, are considered as components of the GnRH pulse generator that produces rhythmic GnRH secretion. The present study aimed to investigate if peripheral administration of PF-4455242, a κ-opioid receptor (KOR, a dynorphin A receptor) antagonist, facilitates pulsatile luteinizing hormone (LH) secretion and GnRH pulse generator activity in estrogen-treated ovariectomized Shiba goats to determine the possibility of using KOR antagonists to artificially control ovarian activities. PF-4455242 was intravenously infused for 4 h (1 or 10 μmol/kg body weight/4 h) or as a single subcutaneous injection (1 or 10 μmol/kg body weight). In a separate experiment, the same KOR antagonist (10 μmol/kg body weight/4 h) was intravenously infused during the recording of multiple unit activity (MUA) in the ARC that reflects the activity of the GnRH pulse generator to test the effects of KOR antagonist administration on GnRH pulse generator activity. Intravenous infusion and single subcutaneous injection of the KOR antagonist significantly increased the frequency of LH pulses compared with controls. Intravenous infusion of KOR antagonist also significantly increased the frequency of episodic bursts in the MUA. The present study demonstrates that peripherally administered KOR antagonist stimulates pulsatile LH secretion by acting on the GnRH pulse generator, and peripheral administration of PF-4455242 can be used to facilitate pulsatile LH secretion, which in turn facilitates ovarian activities in farm animals.

Dynactin is involved in Lewy body pathology

Dynactin forms a protein complex with dynein that retrogradely transports cargo along microtubules. Dysfunction of this dynein-dynactin complex causes several neurodegenerative diseases such as Perry syndrome, motor neuron diseases and progressive supranuclear palsy. Recently, we reported colocalization of phosphorylated α-synuclein (p-SNCA) and the largest subunit of dynactin (DCTN1) in Lewy body (LB)-like structures in Perry syndrome. Previous reports have not focused on the relationship between dynactin and synucleinopathies. Thus, we examined autopsied human brains from patients with Parkinson's disease, dementia with LBs, and multiple system atrophy using immunohistochemistry for p-SNCA, DCTN1, dynactin 2 (DCTN2, dynamitin) and dynein cytoplasmic 1 intermediate chain 1 (DYNC1I1). We also examined microtubule affinity-regulating kinases (MARKs), which phosphorylate microtubule-associated proteins and trigger microtubule disruption. Both brainstem-type and cortical LBs were immunopositive for DCTN1, DCTN2, DYNC1I1 and p-MARK and their staining often overlapped with p-SNCA. Lewy neurites were also immunopositive for DCTN1, DCTN2 and DYNC1I1. However, p-SNCA-positive inclusions of multiple system atrophy, which included both glial and neuronal cytoplasmic inclusions, were immunonegative for DCTN1, DCTN2, DYNC1I1 and p-MARK. Thus, immunohistochemistry for dynein-dynactin complex molecules, especially DCTN1, can clearly distinguish LBs from neuronal cytoplasmic inclusions. Our results suggest that dynactin is closely associated with LB pathology.

Spatial distribution of hydrogen sulfide and sulfur species in coastal marine sediments Hiroshima Bay, Japan

This study aims to reveal spatial distribution of hydrogen sulfide and sulfur species in marine sediments in Hiroshima Bay, Japan, by direct analyses using a combination of detection tubes and X-ray absorption fine structure spectroscopy. In summer and autumn, the hydrogen sulfide concentration ranged from <0.1 to 4 mg-S L^-1. In this study, only hydrogen sulfide was observed in autumn and at two stations in summer. In contrast, some earlier studies reported in all seasons in Hiroshima Bay the presence of acid volatile sulfide, which is used as a proxy of sulfide content. The sulfur species in sediments were mainly identified as sulfate, thiosulfate, elemental sulfur, and pyrite. Thiosulfate was a minor component compared to the other sulfur species. The formation of pyrite and sulfur derived from hydrogen sulfide oxidation played an important role in the scavenging of hydrogen sulfide.

Mitochondrial dysfunction and altered ribostasis in hippocampal neurons with cytoplasmic inclusions of multiple system atrophy

Multiple system atrophy (MSA) is a sporadic adult-onset neurodegenerative disease. It has recently been shown that patients with MSA accompanied by cognitive decline display numerous neuronal cytoplasmic inclusions (NCIs) in the limbic neurons. We examined potential mechanisms underlying the formation of these NCIs by determining of mitochondrial function and statuses of RNA processing by analyzing 12 pathologically confirmed cases of MSA. Among them, four had cognitive impairment Semiquantitative evaluation using immunohistochemistry analyses revealed a significantly greater NCI burden in the hippocampal cornu ammonis 1 (CA1) subfield, subiculum, and amygdala in the cases with cognitive impairments compared with those without cognitive impairment. Immunofluorescent staining revealed that limbic neurons with NCIs often accelerated production of reactive oxygen species (ROS) and degraded mitochondrial quality control. Immunofluorescent staining also revealed that neurons with these NCIs translocated heterogeneous nuclear ribonucleoprotein A1 (HNRNPA1) from the nucleus and aggregated abnormally at the perinuclear rim. Since the NCIs in the hippocampal neurons of MSA with cognitive impairments were more numerous, the neuronal mitochondrial dysfunction and altered ribostasis observed in NCI formation may be involved in the hippocampal degeneration of MSA.

Establishing diagnostic criteria for Perry syndrome

OBJECTIVE

To establish international diagnostic criteria for Perry syndrome, a disorder characterised by clinical signs of parkinsonism, depression/apathy, weight loss, respiratory symptoms, mutations in the DCTN1 gene and TAR DNA-binding protein 43 (TDP-43) pathology.

METHODS

Data from the published literature and newly identified patients were gathered and analysed during and after the International Symposium on Perry syndrome in Tokyo to identify diagnostic criteria for Perry syndrome.

RESULTS

Eighty-seven patients with Perry syndrome carrying DCTN1 mutations from 20 families were included in this study, and common signs of the disorder were identified, including parkinsonism (95.2% of patients), depression/apathy (71.4%), respiratory symptoms (66.7%) and weight loss (49.2%).

CONCLUSIONS

Based on our findings, we propose the following definitive diagnostic criteria for Perry syndrome: the presence of four cardinal signs of Perry syndrome, accompanied by a mutation in DCTN1; or a family history of the disease, parkinsonism and a mutation in DCTN1; or the presence of four cardinal signs and pathological findings that include nigral neuronal loss and TDP-43 pathology. As patients with Perry syndrome present with uniform clinical, genetic and pathological features, we further propose the disorder be termed 'Perry disease.'

DCTN1 F52L mutation case of Perry syndrome with progressive supranuclear palsy-like tauopathy

INTRODUCTION

Perry syndrome is a rapidly progressive, autosomal dominant parkinsonism characterized by central hypoventilation, depression and severe weight loss. To date, eight DCTN1 mutations have been identified associated with Perry syndrome. A novel F52L DCTN1 mutation case of Perry syndrome is characterized by late-onset parkinsonism and frontotemporal atrophy.

METHODS

A Japanese woman suffered from slowly progressing parkinsonism since age 48. At age 59, she developed central hypoventilation, and required breathing assistance. Gene analysis identified a p.F52L mutation in DCTN1 and she was diagnosed with Perry syndrome. She died of aspiration pneumonia at age 74.

RESULTS

Postmortem examination revealed severe neuronal loss in the substantia nigra and the putamen. Immunohistochemistry for DCTN1 revealed many abnormal aggregates, mainly in neurons in the brainstem and basal ganglia. Additionally, numerous abnormal phosphorylated tau deposits including neurofibrillary tangles, tuft-shaped astrocytes and coiled bodies were observed mainly in the basal ganglia, brainstem and cerebellum. These correspond with the neuropathologic criteria for progressive supranuclear palsy. Colocalization of DCTN1 and tau were occasionally seen. Colocalization of phosphorylated α-synuclein and DCTN1 were also observed in Lewy body-like structures in oculomotor nuclei. Phosphorylated TARDBP-positive neuronal cytoplasmic inclusions were few.

CONCLUSION

In conjunction with long disease duration and aging, our findings suggest that the F52L DCTN1 mutation may evoke severe tauopathy and moderate α-synucleinopathy.

The effect of bolus volume on laryngeal closure and UES opening in swallowing: Kinematic analysis using 320-row area detector CT study

This study investigated the effects of three different volumes of honey-thick liquid on the temporal characteristics of swallowing. Twenty-six healthy subjects (15 males, 11 females) underwent 320-row area detector CT scan while swallowing 3, 10 and 20 mL of honey-thick liquid barium. Three-dimensional images were created at 10 images/s. Kinematic events involving six structures (velopharynx, hyoid bone, epiglottis, laryngeal vestibule (LV), true vocal cords (TVC), upper esophageal sphincter (UES)) and timing of bolus movement were timed using frame by frame analysis. The overall sequence of events did not differ across three volumes; however, increasing bolus volume significantly changed the onset and termination of events. The bolus head reached to pharynx and esophagus earlier and the duration of bolus passing through UES was significantly longer in 10 and 20 mL compared to 3 mL (P < .05). Consequently, the onset of UES opening was significantly earlier with increased volume (P < .05). LV and TVC closure occurred later in 20 mL compared to 3 mL (P < .05). These changes in motion of pharynx and larynx appeared to promote swallow safety by preventing aspiration, suggesting that anatomical structure movements adapt in response to bolus volume. Our findings also suggest that the pharyngeal swallow behaviours may be modified by afferents in the oral cavity. The three-dimensional visualization and quantitative measurements provided by 320-ADCT provide essential benchmarks for understanding swallowing, both normal and abnormal.

Dysphagia in Perry Syndrome: Pharyngeal Pressure in Two Cases

Background

To investigate the impact of dysphagia in Perry syndrome (PS), an autosomal dominant parkinsonism caused by mutation of DCTN1, which is associated with hypoventilation, depression, and weight loss.

Case Presentation

We used tongue pressure measurements and manofluorography to investigate swallowing function in 2 patients with PS. Case 1, a 60-year-old male showing parkinsonism, and case 2, a 49-year-old male admitted with pneumonia, were diagnosed as having PS based on the DCTN1 gene analysis. Case 1 showed a pharyngeal retention of the bolus on videofluorography (VF) and a few swallows were required for its passage into the esophagus. However, tongue pressure and manometry were within the normal range. This patient could eat a normal diet under supervision. Case 2 required artificial ventilation and tube feeding on admission. The VF image showed a slow transfer of the bolus, delayed swallow reflex, and pharyngeal retention of the bolus that required several swallows for its passage into the esophagus. The tongue pressure was within the normal range, but manometry showed a significant decrease in pressure at the hypopharynx and upper esophageal sphincter. The oral intake of the patients was limited to 2 cups of jelly per day.

Conclusions

The investigation of swallowing dysfunction of 2 cases of PS showed that maintaining pharyngeal pressure within the normal range was very important for oral feeding success and prognosis.

Ruxolitinib treatment for GvHD in patients with myelofibrosis

Jak1/2 inhibitor ruxolitinib is a promising agent for treating steroid-refractory GvHD after allogeneic hematopoietic stem cell transplantation (SCT) to produce quick and durable responses. However, optimal dose and tapering schedule of ruxolitinib remain to be determined. Discontinuation of ruxolitinib in myelofibrosis often induces 'withdrawal syndrome' characterized by acute relapse of the disease, but this issue is not well addressed in the treatment of GvHD. Four patients with GvHD (one acute and three chronic) after SCT for myelofibrosis were treated with ruxolitinib. Low-dose ruxolitinib at 5 mg/day was safe and effective, but one of two patients treated at 10 mg/day of ruxolitinib was complicated with severe cytopenia. Withdrawal syndrome developed in one patient, who died of recurrence of GvHD shortly after discontinuation of ruxolitinib. Slow tapering or maintenance with low-dose ruxolitinib inhibited GvHD flare. Our experience calls attention that initiation at low-dose of ruxolitinib may be safe and careful tapering schedule is required to avoid withdrawal syndrome in patients with GvHD after SCT for myelofibrosis.

Cytoplasmic aggregates of dynactin in iPSC-derived tyrosine hydroxylase-positive neurons from a patient with Perry syndrome

BACKGROUND

Perry syndrome is a rare autosomal dominant disorder clinically characterized by parkinsonism with depression/apathy, weight loss, and central hypoventilation. Eight mutations in DCTN1 gene have been reported. A novel disease model is required because the detailed pathogenesis remains unclear.

METHODS

To develop a novel model, we generated induced pluripotent stem cells (iPSCs) from a Perry syndrome patient with F52L mutation in DCTN1, and describe clinical and neuroimaging investigations. We differentiated iPSCs into tyrosine hydroxylase (TH)-positive neurons. Immunocytochemistry analyses of control and mutant were performed.

RESULTS

The patient displayed levodopa responsive parkinsonism. Dopamine transporter single photon emission tomography showed markedly decreased uptake in the striatum, and metaiodobenzylguanidine cardiac scintigraphy also showed decreased uptake. Perry syndrome TH-positive neurons showed dynactin aggregates in cytoplasm.

CONCLUSIONS

TH-positive neurons from Perry syndrome iPSCs recapitulated an aspect of the disease phenotype of Perry syndrome.

Echocardiography versus (201)Tl semi-quantitative gated single photon emission tomography for the evaluation of cardiac disease associated with late stage Duchenne muscular dystrophy

OBJECTIVE

In Duchenne muscular dystrophy (DMD) patients cardiac abnormalities are often detected. In adult DMD patients cardiac disease (CD) is a cause of death which increases by age and is related to respiratory dysfunction. Studies have demonstrated that CD in early DMD can be detected by echocardiography (EC) or semi-quantitative gated single photon emission tomography ((201)Tl SQGS), and the accuracy of these two tests is similar. As the disease advances, evaluation of CD by EC becomes difficult due to thoracic deformity and scoliosis. We compared (201)Tl SQGS and EC in the evaluation of cardiac function in late stage DMD, based on the ejection fraction (EF) value calculated by both tests. Twenty-three males with late stage DMD, 12 to 35 years of age (22.2±7.5), were studied by (201)Tl SQGS and EC. The mean EF value by (201)Tl SQGS was 60.8%±14.1%, which differed from that obtained by EC (52.7%±9.8%, P=0.003). Eleven patients less than 20 years old did not demonstrate a significant difference between the two tests (P=0.06), however, 12 patients over 20 years of age had significantly different results between tests (P=0.002).

CONCLUSION

Although our patients were few we indicated that in DMD patients, aged older than 20 years, at an advanced stage of the disease, the EF values calculated by EC were lower than those by (201)Tl SQGS possibly due to thoracic deformity.

Determination of HLA-A, -C, -B, -DRB1 allele and haplotype frequency in Japanese population based on family study

The present study investigates the human leucocyte antigen (HLA) allele and haplotype frequencies in Japanese population. We carried out the frequency analysis in 5824 families living across Japanese archipelago. The studied population has mainly been typed for the purpose of transplant, especially the hematopoietic stem cell transplantation (HSCT). We determined HLA class I (A, B, and C) and HLA class II (DRB1) using Luminex technology. The haplotypes were directly counted by segregation. A total of 44 HLA‐A, 29 HLA‐C, 75 HLA‐B, and 42 HLA‐DRB1 alleles were identified. In the HLA haplotypes of A‐C‐B‐DRB1 and C‐B, the pattern of linkage disequilibrium peculiar to Japanese population has been confirmed. Moreover, the haplotype frequencies based on family study was compared with the frequencies estimated by maximum likelihood estimation (MLE), and the equivalent results were obtained. The allele and haplotype frequencies obtained in this study could be useful for anthropology, transplantation therapy, and disease association studies.

Selective transport of microplastics and mesoplastics by drifting in coastal waters

The quantity and size distributions of small plastic fragments in the Seto Inland Sea, Japan were investigated using field surveys and a numerical particle-tracking model. The model was used to interpret the distributions of small plastic fragments and the possible transport processes in coastal waters. Of note, the size and quantity of mesoplastics (approximately >5mm) gradually increased close to the coast irrespective of the existence of river mouths, which probably act as a major source of anthropogenic marine debris. Additionally, microplastics were more dominant as we moved further offshore. The numerical model reproduced the near-shore trapping of mesoplastics, suggesting that mesoplastics are selectively conveyed onshore by a combination of Stokes drift and terminal velocity, dependent on fragment sizes. It is suggested that mesoplastics washed ashore on beaches degrade into microplastics, and that the microplastics, which are free from near-shore trapping, are thereafter spread offshore in coastal waters.

Loss of hnRNPA1 in ALS spinal cord motor neurons with TDP-43-positive inclusions

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease characterized by loss of motor neurons and appearance of skein-like inclusions. The inclusions are composed of trans-activation response (TAR) DNA-binding protein 43 (TDP-43), a member of the heterogeneous nuclear ribonucleoprotein (hnRNP) family. hnRNPA1 and hnRNPA2/B1 are hnRNPs that interact with the C-terminus of TDP-43. Using immunohistochemistry, we investigated the association between TDP-43 and hnRNPA1 in ALS spinal motor neurons. We examined spinal cords of seven ALS cases and six muscular dystrophy cases (used as controls) for the presence of TDP-43 and hnRNPA1 protein. In the control cases, hnRNPA1 immunoreactivity in motor neurons was intense in the nucleus and weak in the cytoplasm where it showed a fine granular appearance. In the ALS cases, hnRNPA1 immunoreactivity in motor neurons was reduced in the nuclei of neurons with skein-like inclusions but was not detected in the skein-like inclusions. The marked loss of hnRNPA1 in motor neurons with concomitant cytoplasmic aggregation of TDP-43 may represent a severe disturbance of mRNA processing, suggesting a key role in progressive neuronal death in ALS.

Observing Vibrational Energy Flow in a Protein with the Spatial Resolution of a Single Amino Acid Residue

One of the challenges in physical chemistry has been understanding how energy flows in a condensed phase from the microscopic viewpoint. To address this, space-resolved information at the molecular scale is required but has been lacking due to experimental difficulties. We succeeded in the real-time mapping of the vibrational energy flow in a protein with the spatial resolution of a single amino acid residue by combining time-resolved resonance Raman spectroscopy and site-directed single-Trp mutagenesis. Anti-Stokes Raman intensities of the Trp residues at different sites exhibited different temporal evolutions, reflecting propagation of the energy released by the heme group. A classical heat transport model was not able to reproduce the entire experimental data set, showing that we need a molecular-level description to explain the energy flow in a protein. The systematic application of our general methodology to proteins with different structural motifs may provide a greatly increased understanding of the energy flow in proteins.

Is sense of coherence helpful in coping with caregiver burden for dementia?

BACKGROUND

Sense of coherence (SOC) is associated with a reduced risk of various health problems and is thought to be a major factor related to the ability to cope with stress. In the present study, we examined the association between caregiver burden and SOC among caregivers to persons with dementia.

METHODS

Participants included 274 caregivers or family members of community-dwelling elderly dementia patients. To assess the cognitive function of patients, neuropsychological tests (e.g. Mini-Mental State Examination, Clinical Dementia Rating) were conducted by a clinical psychologist who was well trained in interviewing participants; the tests used a semi-structured interview protocol. Senior neurologists and psychiatrists also independently evaluated the dementia status of patients. To assess the SOC and caregiver burden, a social welfare counsellor asked questions from a 13-item version of the SOC scale and the short, eight-item Japanese version of the Zarit Caregiver Burden Interview (ZBI).

RESULTS

Among 78 caregivers of elderly subjects with cognitive impairment due to dementia, the ZBI score was significantly associated with SOC (r = -0.38, P = 0.001). Multiple regression analyses revealed that SOC scores (β = -0.42, P < 0.001) and Mini-Mental State Examination scores (β = -0.28, P = 0.009) were significantly associated with ZBI scores (F(2, 76)  = 10.51, P < 0.001). SOC was closely associated with personal strain in the ZBI (β = -0.41, P < 0.001; F(3, 75)  = 8.53, P < 0.001).

CONCLUSION

Caregivers with a strong SOC may be less prone to experiencing personal strain from their burden. These results suggest that reinforcement of SOC would contribute to reducing the personal strain.

A novel DCTN1 mutation with late-onset parkinsonism and frontotemporal atrophy

BACKGROUND

Depression, parkinsonism, and hypoventilation (Perry syndrome) or familial motor neuron disease have been linked to mutations in dynactin P150(Glued) (DCTN1).

METHODS

We employed genealogic, clinical, neurologic, and MRI investigations, as well as analysis of genes implicated in parkinsonism. Cellular transfection, immunocytochemistry, and immunoprecipitation analysis of wild-type (WT) and mutant DCTN1 were also performed.

RESULTS

A novel heterozygous mutation, DCTN1 c.156T>G, encoding p.Phe52Leu, segregates with parkinsonism in a Japanese family. The substitution was not observed in affected probands with familial parkinsonism or control subjects and is evolutionarily conserved. In contrast to Perry syndrome, affected carriers have late-onset disease and slower progression, with frontotemporal atrophy revealed by MRI. In vitro studies suggest the mutant protein has impaired microtubule binding, compared to WT dynactin p150(Glued) .

CONCLUSIONS

DCTN1 mutations may contribute to disparate neurodegenerative diagnoses, including familial motor neuron disease, parkinsonism, and frontotemporal atrophy, and further studies of dynactin-mediated cargo transport may prove insightful.

[An autopsy case of Alzheimer's disease presenting with corticobasal syndrome]

A right-handed Japanese man developed memory loss at 51 years of age. The right side clumsiness developed from 52 years of age and then progressively worsened. Temporal/parietal lobe atrophy was observed predominantly on the left side upon MR imaging. Subsequently, limb-kinetic apraxia and parkinsonism became apparent predominantly on the right side. These symptoms became aggravated along with dementia, ultimately leading to an apallic state. The patient eventually died at the age of 59 due to aspiration pneumonia. An autopsy was carried out and cerebral atrophy was observed predominantly on the left side. Senile plaques were observed on the entire cerebral cortex at a high frequency, along with many cotton wool plaques. Anti-phosphorylated tau-positive neurofibrillary tangles and several neuropil threads were observed upon immunostaining. The tau-positive structures were also positive for both RD3 and RD4 antibodies. The findings of tauopathy of the glia were poor, and the tau lesion of the brainstem was milder than that of the cerebral cortex. These results suggest the possibility that the corticobasal syndrome clinically developed in some type of Alzheimer's disease and a definite diagnosis was made only by pathological examination.

Clinical features and a mutation with late onset of limb girdle muscular dystrophy 2B

OBJECTIVE AND METHODS

Dysferlin encoded by DYSF deficiency leads to two main phenotypes, limb girdle muscular dystrophy (LGMD) 2B and Miyoshi myopathy. To reveal in detail the mutational and clinical features of LGMD2B in Japan, we observed 40 Japanese patients in 36 families with LGMD2B in whom dysferlin mutations were confirmed.

RESULTS AND CONCLUSIONS

Three mutations (c.1566C>G, c.2997G>T and c.4497delT) were relatively more prevalent. The c.2997G>T mutation was associated with late onset, proximal dominant forms of dysferlinopathy, a high probability that muscle weakness started in an upper limb and lower serum creatine kinase (CK) levels. The clinical features of LGMD2B are as follows: (1) onset in the late teens or early adulthood, except patients homozygous for the c.2997G>T mutation; (2) lower limb weakness at onset; (3) distal change of lower limbs on muscle CT at an early stage; (4) impairment of lumbar erector spinal muscles on muscle CT at an early stage; (5) predominant involvement of proximal upper limbs; (6) preservation of function of the hands at late stage; (7) preservation of strength in neck muscles at late stage; (8) lack of facial weakness or dysphagia; (9) avoidance of scoliosis; (10) hyper-Ckaemia; (11) preservation of cardiac function; and (12) a tendency for respiratory function to decline with disease duration. It is important that the late onset phenotype is found with prevalent mutations.