Effects of empagliflozin on progression of chronic kidney disease: a prespecified secondary analysis from the empa-kidney trial

BACKGROUND

Sodium-glucose co-transporter-2 (SGLT2) inhibitors reduce progression of chronic kidney disease and the risk of cardiovascular morbidity and mortality in a wide range of patients. However, their effects on kidney disease progression in some patients with chronic kidney disease are unclear because few clinical kidney outcomes occurred among such patients in the completed trials. In particular, some guidelines stratify their level of recommendation about who should be treated with SGLT2 inhibitors based on diabetes status and albuminuria. We aimed to assess the effects of empagliflozin on progression of chronic kidney disease both overall and among specific types of participants in the EMPA-KIDNEY trial.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA), and included individuals aged 18 years or older with an estimated glomerular filtration rate (eGFR) of 20 to less than 45 mL/min per 1·73 m2, or with an eGFR of 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher. We explored the effects of 10 mg oral empagliflozin once daily versus placebo on the annualised rate of change in estimated glomerular filtration rate (eGFR slope), a tertiary outcome. We studied the acute slope (from randomisation to 2 months) and chronic slope (from 2 months onwards) separately, using shared parameter models to estimate the latter. Analyses were done in all randomly assigned participants by intention to treat. EMPA-KIDNEY is registered at ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and then followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroups of eGFR included 2282 (34·5%) participants with an eGFR of less than 30 mL/min per 1·73 m2, 2928 (44·3%) with an eGFR of 30 to less than 45 mL/min per 1·73 m2, and 1399 (21·2%) with an eGFR 45 mL/min per 1·73 m2 or higher. Prespecified subgroups of uACR included 1328 (20·1%) with a uACR of less than 30 mg/g, 1864 (28·2%) with a uACR of 30 to 300 mg/g, and 3417 (51·7%) with a uACR of more than 300 mg/g. Overall, allocation to empagliflozin caused an acute 2·12 mL/min per 1·73 m2 (95% CI 1·83-2·41) reduction in eGFR, equivalent to a 6% (5-6) dip in the first 2 months. After this, it halved the chronic slope from -2·75 to -1·37 mL/min per 1·73 m2 per year (relative difference 50%, 95% CI 42-58). The absolute and relative benefits of empagliflozin on the magnitude of the chronic slope varied significantly depending on diabetes status and baseline levels of eGFR and uACR. In particular, the absolute difference in chronic slopes was lower in patients with lower baseline uACR, but because this group progressed more slowly than those with higher uACR, this translated to a larger relative difference in chronic slopes in this group (86% [36-136] reduction in the chronic slope among those with baseline uACR <30 mg/g compared with a 29% [19-38] reduction for those with baseline uACR ≥2000 mg/g; ptrend<0·0001).

INTERPRETATION

Empagliflozin slowed the rate of progression of chronic kidney disease among all types of participant in the EMPA-KIDNEY trial, including those with little albuminuria. Albuminuria alone should not be used to determine whether to treat with an SGLT2 inhibitor.

FUNDING

Boehringer Ingelheim and Eli Lilly.

Impact of primary kidney disease on the effects of empagliflozin in patients with chronic kidney disease: secondary analyses of the EMPA-KIDNEY trial

BACKGROUND

The EMPA-KIDNEY trial showed that empagliflozin reduced the risk of the primary composite outcome of kidney disease progression or cardiovascular death in patients with chronic kidney disease mainly through slowing progression. We aimed to assess how effects of empagliflozin might differ by primary kidney disease across its broad population.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA). Patients were eligible if their estimated glomerular filtration rate (eGFR) was 20 to less than 45 mL/min per 1·73 m2, or 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher at screening. They were randomly assigned (1:1) to 10 mg oral empagliflozin once daily or matching placebo. Effects on kidney disease progression (defined as a sustained ≥40% eGFR decline from randomisation, end-stage kidney disease, a sustained eGFR below 10 mL/min per 1·73 m2, or death from kidney failure) were assessed using prespecified Cox models, and eGFR slope analyses used shared parameter models. Subgroup comparisons were performed by including relevant interaction terms in models. EMPA-KIDNEY is registered with ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroupings by primary kidney disease included 2057 (31·1%) participants with diabetic kidney disease, 1669 (25·3%) with glomerular disease, 1445 (21·9%) with hypertensive or renovascular disease, and 1438 (21·8%) with other or unknown causes. Kidney disease progression occurred in 384 (11·6%) of 3304 patients in the empagliflozin group and 504 (15·2%) of 3305 patients in the placebo group (hazard ratio 0·71 [95% CI 0·62-0·81]), with no evidence that the relative effect size varied significantly by primary kidney disease (pheterogeneity=0·62). The between-group difference in chronic eGFR slopes (ie, from 2 months to final follow-up) was 1·37 mL/min per 1·73 m2 per year (95% CI 1·16-1·59), representing a 50% (42-58) reduction in the rate of chronic eGFR decline. This relative effect of empagliflozin on chronic eGFR slope was similar in analyses by different primary kidney diseases, including in explorations by type of glomerular disease and diabetes (p values for heterogeneity all >0·1).

INTERPRETATION

In a broad range of patients with chronic kidney disease at risk of progression, including a wide range of non-diabetic causes of chronic kidney disease, empagliflozin reduced risk of kidney disease progression. Relative effect sizes were broadly similar irrespective of the cause of primary kidney disease, suggesting that SGLT2 inhibitors should be part of a standard of care to minimise risk of kidney failure in chronic kidney disease.

FUNDING

Boehringer Ingelheim, Eli Lilly, and UK Medical Research Council.

Classification of Patients with Painful Tumors to Predict the Response to Palliative Radiotherapy

PURPOSE/OBJECTIVE(S)

Palliative radiotherapy is an effective and commonly used treatment for pain relief in metastatic cancer patients. This study aimed to classify the patients to predict their response to palliative radiotherapy.

MATERIALS/METHODS

This study used the data from our single-center, prospective observational study (UMIN000044984), which included all patients undergoing palliative radiotherapy for the painful tumor, except for postoperative setting or brain metastases. The eligibility criteria were as follows: (1) numerical rating scale (NRS) was two or more before treatment, and (2) underwent palliative radiotherapy between August 2021 and September 2022. Questionnaires for pain site, NRS, and presence/dose of opioids were obtained before, on the last day of treatment, two weeks later, one month later, three months later, and every three months after that. Patients with severe performance status (PS) were contacted by telephone. Pain response was defined to reduce NRS 2 or more at the treated site without an analgesic increase. The primary outcome was the response rate within three months of the treatment. We used multivariable logistic regression to find the independent prognostic factors for the response based on the following covariates: age, sex, PS, body mass index, NRS, history of radiotherapy, treated site, radiographic features (lytic/sclerotic/mixed), metastatic complication, presence/dose of opioids, bone-modifying agents, radiation dose, type of primary tumor, radiosensitivity, number of metastases, and days from diagnosis to treatment. A classification model was created using significant factors, and response rates were calculated for each class. Statistical significance was defined as P<0.05.

RESULTS

Among 488 targets of 300 patients registered, 366 targets of 261 patients met the criteria. The median age was 65 years, 44% were female, and PS (0/1/2/3/4) was 6/63/18/9/4%. The major type of tumor was gastrointestinal (32%), lung (19%), and breast (12%). Bone metastases were 75% at treated sites. Opioids were used by 72%, BMA was 27%, and chemotherapy was 50%. Re-irradiation rate was 22%. With a median follow-up of 5.8 months, 113 patients were alive, 129 had died, and 20 were lost follow-up. The average NRS was reduced from 6.1 to 3.1 from pretreatment to 3 months later per evaluable 232 targets, resulting in a pain relief rate of 60%. Opioids use (P<0.001) and re-irradiation (P<0.001) were significant factors of poor response in multivariate analysis. In our classification model, 89 targets were classified as class 1 (no opioids & no irradiation history), 211 were class 2 (other than class 1 and 3), and 66 were class 3 (opioids & re-irradiation), were 75/61/36% (P<0.001) of response rate. The 6-month cumulative pain progression rate was 12/22/32% (P<0.001), respectively.

CONCLUSION

Palliative radiotherapy is highly effective for patients with painful tumors especially for those without previous irradiation history or use of opioids.

Anti-IL-5/5Ra biologics improve work productivity and activity in severe asthma: A RAPSODI registry-based cohort study

INTRODUCTION

Severe asthma is associated with a serious disease burden, partially caused by limitations in activity and work impairment (1,2).

AIMS AND OBJECTIVES

This study aims to relate treatment with biologics targeting IL-5/5Ra to work productivity and activity in the long term in a real-world context.

MATERIAL AND METHODS

This is a registry-based multi-center cohort study evaluating data from adults with severe eosinophilic asthma included in the Dutch Register of Adult Patients with Severe Asthma for Optimal DIsease management (RAPSODI). Patients that started with anti-IL-5/5Ra biologics and completed the work productivity and activity improvement questionnaire, were included. Study and patient characteristics were compared between the employed and unemployed patients. Work productivity and activity impairment are related to accompanying improvements in clinical outcomes.

RESULTS

At baseline, 91 of 137 patients (66%) were employed which remained stable throughout the follow-up period. Patients in the working age category were younger and had significantly better asthma control (p =0.02). Mean overall work impairment due to health decreased significantly from 25.5% (SD2.6) to 17.6% (SD 2.8) during 12 months anti-IL-5/5Ra biologics treatment (P = 0.010). There was a significant association between ACQ6 and overall work improvement after targeted therapy (β =8.7, CI 2.1-15.4, P = 0.01). The improvement of asthma control of 0.5 points on the asthma Control Questionnaire was associated with an overall work impairment of - 9%.

CONCLUSIONS

Work productivity and activity in severe eosinophilic asthma improved after starting anti-IL-5/5Ra biologics. Clinically relevant improvement in asthma control was associated with an overall work impairment score of - 9% in this study.

Neuronal glutathione loss leads to neurodegeneration involving gasdermin activation

Accumulating evidence suggests that glutathione loss is closely associated with the progression of neurodegenerative disorders. Here, we found that the neuronal conditional-knockout (KO) of glutamyl-cysteine-ligase catalytic-subunit (GCLC), a rate-limiting enzyme for glutathione synthesis, induced brain atrophy accompanied by neuronal loss and neuroinflammation. GCLC-KO mice showed activation of C1q, which triggers engulfment of neurons by microglia, and disease-associated-microglia (DAM), suggesting that activation of microglia is linked to the neuronal loss. Furthermore, gasdermins, which regulate inflammatory form of cell death, were upregulated in the brains of GCLC-KO mice, suggesting the contribution of pyroptosis to neuronal cell death in these animals. In particular, GSDME-deficiency significantly attenuated the hippocampal atrophy and changed levels of DAM markers in GCLC-KO mice. Finally, we found that the expression of GCLC was decreased around amyloid plaques in App^NL-G-F AD model mice. App^NL-G-F mouse also exhibited inflammatory events similar to GCLC-KO mouse. We propose a mechanism by which a vicious cycle of oxidative stress and neuroinflammation enhances neurodegenerative processes. Furthermore, GCLC-KO mouse will serve as a useful tool to investigate the molecular mechanisms underlying neurodegeneration and in the development of new treatment strategies to address neurodegenerative diseases.

Tau-binding protein PRMT8 facilitates vacuole degeneration in the brain

Amyloid-β (Aβ) and tau pathologies are important factors leading to neurodegeneration in Alzheimer's disease (AD); however the molecular mechanisms that link these pathologies remain unclear. Assuming that important though as yet unidentified factors inhibit/accelerate tau pathology and neuronal cell death under amyloid pathology, we sought to isolate and identify tau-interacting proteins from mouse brains with or without amyloid pathology. Among the proteins that were identified, we focused on protein arginine methyltransferase 8 (PRMT8), which interacts with tau specifically in the absence of amyloid pathology. To investigate the role of PRMT8 in the pathogenesis of AD, we conducted Prmt8 gene deletion and overexpression experiments in AppNL-G-F/MAPT double-knock-in (dKI) mice and analyzed the resulting pathological alterations. PRMT8-knockout did not alter the AD pathology in dKI mice, whereas PRMT8-overexpression promoted tau phosphorylation, neuroinflammation, and vacuole degeneration. To evaluate if such a PRMT8-induced vacuole degeneration depends on tau pathology, PRMT8 was overexpressed in tau-KO mice, which were consequently found to exhibit vacuole degeneration. In addition, proteomic analyses showed that PRMT8 overexpression facilitated the arginine methylation of vimentin. Abnormal protein methylation could be involved in PRMT8-induced brain pathologies. Taken together, PRMT8 may play an important role in the formation of tau pathology and vacuole degeneration.

P-218 Mitochondria transfer from adipose stem cell ameliorates the development potential of cryopreserved oocytes

Study question

Could autologous adipose stem cell (ASC) mitochondria supplementation restore the post-fertilization development potentialin vitrified-thawed oocytes?

Summary answer

Autologous ASC mitochondria supplementation could rejuvenate the quality of vitrified-thawed oocytes and enhance the embryo’s developmental capacity.

What is known already

Pre- and post-implantation developmental potential of embryos derived from vitrified oocytes are remarkedly lower than those of fresh oocytes. Despite its’ low efficacy, oocyte cryopreservation is becoming prevalent in assisted reproductive technologies to cater the growing demands due to patients' sociological and pathological conditions. Unfavorable effects to mitochondrial membrane potential, mitochondrial structure, ATP production, reactive oxygen species (ROS), meiotic spindle and microfilaments, and Ca2+ ion regulation are reported as detrimental damages in oocytes following the cryopreservation, that adversely affect the development potential. Furthermore, autologous stem cell mitochondria supplementation can rescue the aging-related oocyte mitochondrial damages.

Study design, size, duration

The mature oocytes, autologous ASC, and mitochondria were collected from young mice and analyzed at Osaka City University, Japan. In total, 600 young mouse mature oocytes were occupied in this prospective study.

Participants/materials, setting, methods

Young C57BL/6JJmsmouse (8weeks) mature oocytes that have been pre-vitrified were thawed before the start of the ICSI procedure.ASC specificity and ASC mitochondria function and ultrastructure were pre-analyzed. ASC mitochondria were isolated on the same day and supplemented with intracellular sperm injection (ICSI) and as the control, the mitochondrial buffer was injected. The survival rate, fertilization rate, blastulation, mitochondria function, ROS level in 2 cell embryos, and live birth rates were compared between the 2 groups.

Main results and the role of chance

The ASC mitochondriashowed higher membrane potential compared to the somatic cells and were spherical in shape with low cristae numbers. The survival rate and the fertilization ratewere comparable in both mitochondria supplemented and control groups. However, theASC mitochondria supplementation seemed to havesignificantly improvedthe blastocyst development capacity from 2cell embryos compared to the control group (P &lt; 0.05;56.8% & 38.2%, respectively).And interestingly, a significantly higher ATP level was found in the mitochondria supplemented group’s 2 cell embryos thanin the control group (P &lt; 0.05;905.6pmol & 561.1pmol respectively). And though it was not statistically significant, a higher potential ofgetting live birth was found in the mitochondria supplemented group thanthe control group after 2 cell embryo transfer.

Limitations, reasons for caution

We acknowledge that the absence of compared data with fresh oocytes’ ICSI, the detailed cellular mechanism behind theimprovement of embryo development, and transgenerational safety in offspring developed fromthe mitochondria supplementation werethe limitations of this study.

Wider implications of the findings

With these results, we propose that ASC mitochondria supplementation could rejuvenate the quality of cryopreserved oocytes and enhance the embryo developmental capacity, signifying another possible approach of mitochondrial transplantation therapy.

Trial registration number

not applicable

P-200 An addition of nicotinamide adenine dinucleotide (NAD+) precursor to oocyte maturation medium improves the developmental competence of bovine oocytes after IVF

Study question

Does an increase of nicotinamide adenine dinucleotide (NAD+) level in oocytes lead to an improvement of blastulation after IVF?

Summary answer

The addition of NAD+ precursor to the oocyte maturation medium increased NAD+ levels in the oocytes, improving the developmental competence to the blastocyst after IVF.

What is known already

With maternal ageing, the enzyme that degrades NAD+ (CD38) increases in cells and the amount of NAD+ in cells, including oocytes, decreases. The degradation of NAD+ is also increased when cells are isolated from tissues. NAD+, which is an electron carrier used by all eukaryotes, is reduced to NADH via beta-oxidation of fatty acids and the TCA cycle, enhancing ATP synthesis in the mitochondrial electron transfer system. In addition, an enzyme in the inner mitochondrial membrane donates protons from NADH to NADP+ to synthesize NADPH, which maintains the intracellular redox state.

Study design, size, duration

This study is a prospective study using bovine oocytes retrieved from ovaries obtained from a local slaughterhouse in Osaka city. A total of 2,501 bovine oocytes were used in this study.

Participants/materials, setting, methods

Bovine cumulus-oocyte-complexes (COCs) were matured in vitro in the culture (IVM) medium supplemented with 0-100 μM nicotinamide mononucleotide (NMN). Matured oocytes were inseminated with the washed spermatozoa and cultured to assess the blastulation. Matured oocytes were also used to examine their NAD+, reactive oxygen species (ROS) and ATP levels.

Main results and the role of chance

The addition of NMN to the IVM medium increased intracellular NAD+ levels of bovine mature oocytes at 1 µM and above. As a result, it increased intracellular ATP levels and decreased ROS levels at 10 µM and above. It also improved blastocyst formation rates after IVF at 100 µM (P &lt; 0.05; 35%) compared with control (22.2%). Moreover, the supplementation of NMN to the IVM medium decreased the percentage of apoptotic cells and intracellular ROS levels in cumulus cells surrounding oocytes.

Limitations, reasons for caution

This study was conducted in vitro using bovine oocytes. Thus, studies using human samples should be performed before clinical application.

Wider implications of the findings

By replenishing NAD+, we have found a clue to improving the IVM and IVF outcome, which has been shown to have a lower blastocyst formation rate than conventional IVF methods using in vivo matured oocytes. It may also improve the developmental potential of oocytes retrieved from older women.

Trial registration number

not applicable

An isogenic panel of App knock-in mouse models: Profiling β-secretase inhibition and endosomal abnormalities

We previously developed single App knock-in mouse models of Alzheimer's disease (AD) that harbor the Swedish and Beyreuther/Iberian mutations with or without the Arctic mutation (App^NL-G-F and App^NL-F mice). We have now generated App knock-in mice devoid of the Swedish mutations (App^G-F mice) and evaluated its characteristics. Amyloid β peptide (Aβ) pathology was exhibited by App^G-F mice from 6 to 8 months of age and was accompanied by neuroinflammation. Aβ-secretase inhibitor, verubecestat, attenuated Aβ production in App^G-F mice, but not in App^NL-G-F mice, indicating that the App^G-F mice are more suitable for preclinical studies of β-secretase inhibition given that most patients with AD do not carry the Swedish mutations. Comparison of isogenic App knock-in lines revealed that multiple factors, including elevated C-terminal fragment β (CTF-β) and humanization of Aβ might influence endosomal alterations in vivo. Thus, experimental comparisons between different isogenic App, knock-in mouse lines will provide previously unidentified insights into our understanding of the etiology of AD.

Peritoneal natural killer cell chemotaxis is decreased in women with pelvic endometriosis

PROBLEM

NK cell and macrophage function are decreased in endometriosis, and the disease may involve reduced immune surveillance in the peritoneal cavity. NK cell cytotoxicity and migration ability (chemotaxis) are considered important; the former has been investigated, but the latter has not.

METHOD OF STUDY

We compared chemotaxis of immunocompetent cells (NK cells, macrophages, T cells) in peritoneal fluid obtained during laparoscopy in 27 women with and 13 without endometriosis. Peripheral blood NK cells were also obtained by the peripheral blood antibody beads method. Micro-cultured cells were examined by time-lapse photography, and the mean migration speed per cell was calculated as the chemotaxis. We investigated the relationship between chemotaxis and endometriosis.

RESULTS

NK cell chemotaxis was significantly lower in the endometriosis group. Macrophages and lymphocytes were not significantly different between the groups. During menstruation, NK cell chemotaxis decreased in both groups. Postmenstrual chemotaxis was increased significantly in women without endometriosis but remained low in women with endometriosis. The Revised-American Society for Reproductive Medicine score was not correlated with chemotaxis; in women with endometriosis, chemotaxis was decreased even at early stages. Peripheral blood NK cells showed no significant differences.

CONCLUSIONS

In women with endometriosis, not only cytotoxicity but also chemotaxis by NK cells in peritoneal cavity is significantly decreased, and particularly chemotaxis is decreased throughout the menstrual cycle. Therefore, antigens in retrograde menstrual blood that enters the peritoneal cavity might be left unprocessed. Repetition of this immune process in the peritoneal cavity may lead to the onset and subsequent progression of endometriosis.

Recent Advances in the Modeling of Alzheimer's Disease

Since 1995, more than 100 transgenic (Tg) mouse models of Alzheimer's disease (AD) have been generated in which mutant amyloid precursor protein (APP) or APP/presenilin 1 (PS1) cDNA is overexpressed ( 1st generation models ). Although many of these models successfully recapitulate major pathological hallmarks of the disease such as amyloid β peptide (Aβ) deposition and neuroinflammation, they have suffered from artificial phenotypes in the form of overproduced or mislocalized APP/PS1 and their functional fragments, as well as calpastatin deficiency-induced early lethality, calpain activation, neuronal cell death without tau pathology, endoplasmic reticulum stresses, and inflammasome involvement. Such artifacts bring two important uncertainties into play, these being (1) why the artifacts arise, and (2) how they affect the interpretation of experimental results. In addition, destruction of endogenous gene loci in some Tg lines by transgenes has been reported. To overcome these concerns, single App knock-in mouse models harboring the Swedish and Beyreuther/Iberian mutations with or without the Arctic mutation (AppNL-G-F and AppNL-F mice) were developed ( 2nd generation models ). While these models are interesting given that they exhibit Aβ pathology, neuroinflammation, and cognitive impairment in an age-dependent manner, the model with the Artic mutation, which exhibits an extensive pathology as early as 6 months of age, is not suitable for investigating Aβ metabolism and clearance because the Aβ in this model is resistant to proteolytic degradation and is therefore prone to aggregation. Moreover, it cannot be used for preclinical immunotherapy studies owing to the discrete affinity it shows for anti-Aβ antibodies. The weakness of the latter model (without the Arctic mutation) is that the pathology may require up to 18 months before it becomes sufficiently apparent for experimental investigation. Nevertheless, this model was successfully applied to modulating Aβ pathology by genome editing, to revealing the differential roles of neprilysin and insulin-degrading enzyme in Aβ metabolism, and to identifying somatostatin receptor subtypes involved in Aβ degradation by neprilysin. In addition to discussing these issues, we also provide here a technical guide for the application of App knock-in mice to AD research. Subsequently, a new double knock-in line carrying the AppNL-F and Psen1 P117L/WT mutations was generated, the pathogenic effect of which was found to be synergistic. A characteristic of this 3rd generation model is that it exhibits more cored plaque pathology and neuroinflammation than the AppNL-G-F line, and thus is more suitable for preclinical studies of disease-modifying medications targeting Aβ. Furthermore, a derivative AppG-F line devoid of Swedish mutations which can be utilized for preclinical studies of β-secretase modifier(s) was recently created. In addition, we introduce a new model of cerebral amyloid angiopathy that may be useful for analyzing amyloid-related imaging abnormalities that can be caused by anti-Aβ immunotherapy. Use of the App knock-in mice also led to identification of the α-endosulfine-K ATP channel pathway as components of the somatostatin-evoked physiological mechanisms that reduce Aβ deposition via the activation of neprilysin. Such advances have provided new insights for the prevention and treatment of preclinical AD. Because tau pathology plays an essential role in AD pathogenesis, knock-in mice with human tau wherein the entire murine Mapt gene has been humanized were generated. Using these mice, the carboxy-terminal PDZ ligand of neuronal nitric oxide synthase (CAPON) was discovered as a mediator linking tau pathology to neurodegeneration and showed that tau humanization promoted pathological tau propagation. Finally, we describe and discuss the current status of mutant human tau knock-in mice and a non-human primate model of AD that we have successfully created.

Early memory deficits and extensive brain network disorganization in the AppNL-F/MAPT double knock-in mouse model of familial Alzheimer's disease

A critical challenge in current research on Alzheimer's disease (AD) is to clarify the relationship between network dysfunction and the emergence of subtle memory deficits in itspreclinical stage. The AppNL-F/MAPT double knock-in (dKI) model with humanized β-amyloid peptide (Aβ) and tau was used to investigate both memory and network dysfunctions at an early stage. Young male dKI mice (2 to 6 months) were tested in three tasks taxing different aspects of recognition memory affected in preclinical AD. An early deficit first appeared in the object-place association task at the age of 4 months, when increased levels of β-CTF and Aβ were detected in both the hippocampus and the medial temporal cortex, and tau pathology was found only in the medial temporal cortex. Object-place task-dependent c-Fos activation was then analyzed in 22 subregions across the medial prefrontal cortex, claustrum, retrosplenial cortex, and medial temporal lobe. Increased c-Fos activation was detected in the entorhinal cortex and the claustrum of dKI mice. During recall, network efficiency was reduced across cingulate regions with a major disruption of information flow through the retrosplenial cortex. Our findings suggest that early perirhinal-entorhinal pathology is associated with abnormal activity which may spread to downstream regions such as the claustrum, the medial prefrontal cortex and ultimately the key retrosplenial hub which relays information from frontal to temporal lobes. The similarity between our findings and those reported in preclinical stages of AD suggests that the AppNL-F/MAPT dKI model has a high potential for providing key insights into preclinical AD.

A bolus of saline injection leads to increase in coronary flow based on the viscosity reduction effect: the mechanism of saline induced Pd/Pa ratio

Background

In conjunction with fractional flow reserve (FFR), our previous study has shown the accuracy and utility of saline induced Pd/Pa ratio (SPR) for the assessment of myocardial ischemia. However, the potential mechanism how saline injection leads to increase in coronary flow remains speculative.

Purpose

This study aimed to clarify the underlying mechanism of SPR by using swine models.

Methods

The study was conducted in four swine models, and bolus of 25°C saline, 40°C saline, and 25°C dextran was injected at rates of 40mL/5sec through a catheter inserted into the superior mesenteric artery. Its peripheral arterioles were observed and recorded by a digital microscope, and transit time of each fluid and a luminal diameter of arterioles before and after injection were measured.

Results

The result from arterioles diameters of pre- and post-injection (0.049±0.016mm vs. 0.050±0.016mm; P=0.636) indicated that luminal diameters remained unchanged regardless of fluid administration. The transit time of 25°C saline was significantly shorter than 25°C dextran (3.19±0.68sec vs. 6.15±1.19sec; P&lt;0.0001). Although the result showed no significance, the transit time of 40°C saline with lower viscosity was shorten compared to 25°C saline (3.1±0.43sec vs. 3.65±0.46sec; P=0.088).

Conclusions

Compared to 25°C dextran (viscosity of 4.991mPa·s) having the same viscosity as 37°C whole blood, 25°C saline (viscosity of 1.012mPa·s) caused increasing to double the intravascular flow volume without dilating arterioles. The results strongly suggested that the potential mechanism of SPR was viscosity reduction effect. Combined with FFR which is based on vasodilation-mediated hyperemia, these findings may contribute to clarifying the pathophysiology and especially the microcirculation in coronary artery diseases.

Funding Acknowledgement

Type of funding source: None

The developing mechanism of atherosclerotic lesion in coronary side branch on the ventricular free wall differs by the location of lesion

Background

The effective treating method of coronary side branch lesions such as ostial stenosis or thin arteries has not been established. On the other hand, tortuous side branch rarely has stenotic lesions.

Purpose

We focused on coronary side branches on the ventricular free wall, and examined coronary risk factors and bending and stretching motion of branch which can contribute to the development of atherosclerotic lesion.

Methods

In elective and first-time coronary angiograms, we included side branches on the ventricular free wall (&gt;2mm in diameter) and excluded previously treated ones. Study A; we divided arteries into proximal, middle, and distal segment, and examined the presence of tortuosity and stenotic lesions exceeding 50% diameter stenosis (DS) for each segment. A score of 1 was assigned to tortuous segment, and 0 to non-tortuous one. Study B; we included stenotic lesion (&gt;50% DS) in side branch ostium and excluded those extended across main coronary arteries. Relation between lesions and patients' characteristics was examined.

Results

Study A; in 1,828 side branches from 472 patients, middle and distal segments had significantly higher tortuosity score than proximal (0.68, 0.78 vs. 0.34; p&lt;0.0001). On the contrary, proximal segments had more stenotic lesions except ostial stenosis (230 vs. 69, 5; p&lt;0.0001). Study B; in 1,740 side branches from 465 patients, 122 ostial stenotic lesions were found (7.0%). Multivariate logistic regression analysis revealed diabetes mellitus and age as independent contributors to development of ostial stenosis (Table).

Conclusions

Side branch stenosis developed less frequently in middle and distal segments, where stronger ventricular wall motion reinforces bending and stretching motion and tortuosity of arteries. This fact indicates that those characteristics may prevent developing atherosclerosis through increasing shear stress. On the other hand, diabetes mellitus strongly contributes to the development of ostial stenosis. Thus, the developing mechanism of atherosclerotic lesion in side branch on the ventricular free wall differs by the location of lesion.

Funding Acknowledgement

Type of funding source: None

P1742 Occurrence of right ventricle dysfunction in patients with Brugada syndrome: a follow-up study by echocardiography and electrophysiological examination

Background

Brugada syndrome (BrS) has been characterized by no apparent structural abnormalities in both ventricles, but, recently, the presence of subtle right ventricular (RV) structural abnormalities in patients with BrS has been reported.

Purpose

The aim of this study was to evaluate the occurrence of RV dysfunction in patients with BrS and their characteristics.

Methods

We enrolled 49 consecutive patients (54 ± 11 years old) diagnosed with Brs and underwent echocardiography from 2017 to 2018. The echocardiographic parameters and electrophysiological examinations were evaluated including RV size and function such as RV outflow and inflow tract diameter, TAPSE, S’, and FAC. Abnormality threshold for parameters of RV dysfunction is defined as followed: a TAPSE of &lt;17 mm, an S’ of &lt;9.5 cm, and an FAC of &lt;35%.

Results

Among 49 patients, one patient showed a TAPSE of &lt;17 mm, 5 patients an S’ of &lt;9.5 cm, and 10 patients an FAC of &lt;35%. Evaluating characteristics of Brs patients with RV dysfunction, all patients were divided into 2 groups by the value of RV FAC; 39 patients showing FAC &gt;35% (group A), 10 patients FAC ≤35% (group B). The comparison of each parameter between 2 groups is shown in Table. TAPSE and S’ in group B were lower than in group A. RV inflow tract diameter in group B was larger than in group A, although there was no differences in RV out tract diameter. There were no significant differences in left ventricular parameters, and grade of tricuspid regurgitation. QRS duration prolonged and the rate of ICD implantation was higher in group B than in group A. Moreover, all patients in group B showed RV wall motion abnormalities and the distribution was as followed: diffuse (n = 2), RV mid (n = 2), RV apex (n = 6).

Conclusions

BrS patients frequently showed RV dysfunction during follow-up, and it may be related to the prolongation of QRS duration. We should pay much attention to the occurrence of RV dysfunction in follow-up echocardiography.

Group A (FAC &gt;35%) N = 39 Group B (FAC ≤35%) N = 10 p-value TAPSE, mm 22.9 ± 2.1 20.4 ± 2.6 0.009 S", cm/s 12.8 ± 2.0 11.1 ± 1.4 0.010 RV outflow tract, mm 29.7 ± 4.4 31.2 ± 5.0 0.49 RV mid inflow tract, mm 30.4 ± 2.9 33.8 ± 3.7 0.008 RV basal inflow tract, mm 38.5 ± 3.2 43.7 ± 4.0 0.001 QRS duration, ms 112.9 ± 12.9 136.3 ± 28.4 0.006 Late potential positive, n (%) 25 (64) 8 (80) 0.34 ICD implantation, n (%) 19 (68) 9 (90) 0.019

Humanization of the entire murine Mapt gene provides a murine model of pathological human tau propagation

In cortical regions of brains from individuals with preclinical or clinical Alzheimer's disease (AD), extracellular β-amyloid (Aβ) deposition precedes the aggregation of pathological intracellular tau (the product of the gene microtubule-associated protein tau (MAPT)). To our knowledge, current mouse models of tauopathy reconstitute tau pathology by overexpressing mutant human tau protein. Here, through a homologous recombination approach that replaced the entire murine Mapt gene with the human ortholog, we developed knock-in mice with humanized Mapt to create an in vivo platform for studying human tauopathy. Of note, the humanized Mapt expressed all six tau isoforms present in humans. We next cross-bred the MAPT knock-in mice with single amyloid precursor protein (App) knock-in mice to investigate the Aβ-tau axis in AD etiology. The double-knock-in mice exhibited higher tau phosphorylation than did single MAPT knock-in mice but initially lacked apparent tauopathy and neurodegeneration, as observed in the single App knock-in mice. We further observed that tau humanization significantly accelerates cell-to-cell propagation of AD brain-derived pathological tau both in the absence and presence of Aβ-amyloidosis. In the presence of Aβ-amyloidosis, tau accumulation was intensified and closely associated with dystrophic neurites, consistently showing that Aβ-amyloidosis affects tau pathology. Our results also indicated that the pathological human tau interacts better with human tau than with murine tau, suggesting species-specific differences between these orthologous pathogenic proteins. We propose that the MAPT knock-in mice will make it feasible to investigate the behaviors and characteristics of human tau in an animal model.

Aminophospholipids are signal-transducing TREM2 ligands on apoptotic cells

Variants of triggering receptor expressed on myeloid cells 2 (TREM2) are associated with an increased incidence of Alzheimer’s disease, as well as other neurodegenerative disorders. Using a newly developed, highly sensitive reporter cell model, consisting of Jurkat T cells stably overexpressing a reporter gene and a gene encoding TREM2DAP12 fusion protein, we show here that TREM2-dependent signal transduction in response to apoptotic Neuro2a cells is mediated by aminophospholipid ligands, phosphatidylserine and phosphatidylethanolamine, which are not exposed on the intact cell surface, but become exposed upon apoptosis. We also show that signal-transducing TREM2 ligands different from aminophospholipids, which appear to be derived from neurons, might be present in membrane fractions of mouse cerebral cortex. These results may suggest that TREM2 regulates microglial function by transducing intracellular signals from aminophospholipids on apoptotic cells, as well as unidentified ligands in the membranes of the cerebral cortex.

Critical review: involvement of endoplasmic reticulum stress in the aetiology of Alzheimer's disease

The endoplasmic reticulum (ER) stress response is regarded as an important process in the aetiology of Alzheimer's disease (AD). The accumulation of pathogenic misfolded proteins and the disruption of intracellular calcium (Ca²⁺) signalling are considered to be fundamental mechanisms that underlie the induction of ER stress, leading to neuronal cell death. Indeed, a number of studies have proposed molecular mechanisms linking ER stress to AD pathogenesis based on results from in vitro systems and AD mouse models. However, stress responsivity was largely different between each mouse model, even though all of these models display AD-related pathologies. While several reports have shown elevated ER stress responses in amyloid precursor protein (APP) and presenilin 1 (PS1) double-transgenic (Tg) AD mouse models, we and other groups, in contrast, observed no such ER stress response in APP-single-Tg or App-knockin mice. Therefore, it is debatable whether the ER stress observed in APP and PS1 double-Tg mice is due to AD pathology. From these findings, the roles of ER stress in AD pathogenesis needs to be carefully addressed in future studies. In this review, we summarize research detailing the relationship between ER stress and AD, and analyse the results in detail.

Empowering rice seedling growth by endophytic Bradyrhizobium sp. SUTN9-2

Bradyrhizobium sp. strain SUTN9-2 was confirmed as rice endophytic bacteria and also as rice growth promotion agent. SUTN9-2 showed the capability of plant growth promotion characteristics, such as indole-3-acetic acid (IAA) and 1-amino-cyclopropane-1-carboxylic acid (ACC) deaminase productions and nitrogen fixation. In this study, the ability of SUTN9-2 to stimulate rice growth was investigated at different stages with N-free and NH₄ NO₃ under in vivo condition. The rice dry weight and chlorophyll content could be enhanced when SUTN9-2 was inoculated in N-free, especially at seedling stage (7 and 14 dai). The rice dry weight was also increased when SUTN9-2 was inoculated with NH₄ NO₃ at 7 and14 dai. The results of quantitative analysis of IAA and ACC deaminase were inconsistent with the expression of genes involved in IAA (nit) and ACC deaminase (acdS) productions. This inconsistently could implied that IAA and ACC deaminase produced from SUTN9-2 do not directly affect rice growth, but other factors resulting from the production of IAA and ACC deaminase could be involved. Moreover, the expression of genes involved in nitrogen fixation (nifH and nifV) of SUTN9-2 was also induced in rice tissues. This finding suggested that rice growth promotion may be supported by NH₄ NO₃ together with nitrogen fixation by SUTN9-2. SIGNIFICANCE AND IMPACT OF THE STUDY: Indole-3-acetic acid, 1-amino-cyclopropane-1-carboxylic acid deaminase productions and nitrogen fixation may play important roles in rice growth promotion by endophytic SUTN9-2, especially at early rice seedling growth stage, which has the potential to be used as rice seedling growth promoter in the system of rice intensification.

Introduction of pathogenic mutations into the mouse Psen1 gene by Base Editor and Target-AID

Base Editor (BE) and Target-AID (activation-induced cytidine deaminase) are engineered genome-editing proteins composed of Cas9 and cytidine deaminases. These base-editing tools convert C:G base pairs to T:A at target sites. Here, we inject either BE or Target-AID mRNA together with identical single-guide RNAs (sgRNAs) into mouse zygotes, and compare the base-editing efficiencies of the two distinct tools in vivo. BE consistently show higher base-editing efficiency (10.0–62.8%) compared to that of Target-AID (3.4–29.8%). However, unexpected base substitutions and insertion/deletion formations are also more frequently observed in BE-injected mice or zygotes. We are able to generate multiple mouse lines harboring point mutations in the mouse presenilin 1 (Psen1) gene by injection of BE or Target-AID. These results demonstrate that BE and Target-AID are highly useful tools to generate mice harboring pathogenic point mutations and to analyze the functional consequences of the mutations in vivo.

CRISPR-guided cytidine deaminases, including BE3 (Base Editor 3) and Target-AID (activation-induced cytidine deaminase), can covert C:G base pairs to T:A at target site. Here, the authors generate missense mutations of mouse Psen1 gene and find BE3 has higher editing efficiency than Target-AID.

Selective release of miRNAs via extracellular vesicles is associated with house-dust mite allergen-induced airway inflammation

BACKGROUND

MicroRNAs (miRNAs) may facilitate cell-to-cell communication via extracellular vesicles (EVs). The biological roles of miRNAs in EVs on allergic airway inflammation are unclear.

METHODS

Airway-secreted EVs (AEVs) were isolated from bronchoalveolar lavage fluid (BALF) of control and house-dust mite (HDM) allergen-exposed HDM-sensitized mice. The expression of miRNAs in AEVs or miRNAs and mRNAs in lung tissue was analysed using miRNA microarray.

RESULTS

The amount of AEV increased 8.9-fold in BALF from HDM-exposed mice compared with that from sham-control mice. HDM exposure resulted in significant changes in the expression of 139 miRNAs in EVs and 175 miRNAs in lung tissues, with 54 miRNAs being common in both samples. Expression changes of these 54 miRNAs between miRNAs in AEVs and lung tissues after HDM exposure were inversely correlated. Computational analysis revealed that 31 genes, including IL-13 and IL-5Ra, are putative targets of the miRNAs up-regulated in AEVs but down-regulated in lung tissues after HDM exposure. The amount of AEV in BALF after HDM exposure was diminished by treatment with the sphingomyelinase inhibitor GW4869. The treatment with GW4869 also decreased Th2 cytokines and eosinophil counts in BALFs and reduced eosinophil accumulation in airway walls and mucosa.

CONCLUSION

These results indicate that selective sorting of miRNA including Th2 inhibitory miRNAs into AEVs and increase release to the airway after HDM exposure would be involved in the pathogenesis of allergic airway inflammation.

Comparative Studies of Coagulative and Fibrinolytic Faculties between the Japanese Monkey and the Human

In the present study, the coagulative and the fibrinolytic faculties of the Japanese monkey (Macaca fuscata) were investigated and compared with those of the human.

Regarding the coagulative faculty, the plasmic fibrinogen level, prothrombin times, and partial thromboplastin times of the Japanese monkey were similar to those of the human, but the antithrombin level in the monkey was higher than that in the human.

Regarding the fibrinolytic faculty, the simian plasminogen level was significantly higher than the human, but the simian, plasma clot and the euglobulin clot lysis times were extremely prolonged, which means that the Japanese monkey has a great fibrinolytic potential, but that it is difficult to activate.

In addition, the human and simian reactivities of plasminogen to streptokinase were also investigated and compared.

Predictors of benefit from high-altitude climate therapy in adults with severe asthma

BACKGROUND

High-altitude climate therapy has been shown to benefit patients with severe asthma but it is not known which patients benefit most from this treatment. In the current study we aimed to identify clinical, functional and inflammatory predictors of favourable outcome of high-altitude climate therapy.

METHODS

This is a secondary analysis of a prospective cohort including 136 adult patients with a diagnosis of severe refractory asthma, referred to the Dutch Asthma Centre in Davos (1600 metres above sea level), Switzerland. They had assessments of medication usage, asthma-related quality of life (Asthma-related Quality of Life Questionnaire, AQLQ), asthma control, body mass index (BMI), sino-nasal symptoms, fatigue, lung function (forced expiratory volume in one second, FEV1), exercise tolerance, allergy and inflammation (fraction of exhaled nitric oxide, blood eosinophils) at entry and after 12 weeks of treatment. Five clinically relevant outcomes were considered: AQLQ, oral corticosteroid dose, FEV1, body mass index and blood eosinophils. Independent predictors of beneficial outcome were identified by multiple linear regression analysis.

RESULTS

Lower blood eosinophil counts (p < 0.01), younger age (p = 0.02) and poorer asthma control (p < 0.01) were independently associated with greater reduction in the dose of oral corticosteroids. Lower fatigue score at baseline (p = 0.01) was associated with greater weight loss (reduction in BMI). Higher levels of total IgE at baseline (p < 0.01), and higher doses of inhaled corticosteroids (p = 0.03) were associated with greater decreases in blood eosinophils. There were no predictors for improvement in AQLQ or FEV1.

CONCLUSIONS

The beneficial effect of high-altitude climate therapy in adults with severe asthma can be predicted by patient characteristics, such as age, blood eosinophils and degree of asthma control before admission.

Sex-specific relevance of diabetes to occlusive vascular and other mortality: a collaborative meta-analysis of individual data from 980 793 adults from 68 prospective studies

BACKGROUND

Several studies have shown that diabetes confers a higher relative risk of vascular mortality among women than among men, but whether this increased relative risk in women exists across age groups and within defined levels of other risk factors is uncertain. We aimed to determine whether differences in established risk factors, such as blood pressure, BMI, smoking, and cholesterol, explain the higher relative risks of vascular mortality among women than among men.

METHODS

In our meta-analysis, we obtained individual participant-level data from studies included in the Prospective Studies Collaboration and the Asia Pacific Cohort Studies Collaboration that had obtained baseline information on age, sex, diabetes, total cholesterol, blood pressure, tobacco use, height, and weight. Data on causes of death were obtained from medical death certificates. We used Cox regression models to assess the relevance of diabetes (any type) to occlusive vascular mortality (ischaemic heart disease, ischaemic stroke, or other atherosclerotic deaths) by age, sex, and other major vascular risk factors, and to assess whether the associations of blood pressure, total cholesterol, and body-mass index (BMI) to occlusive vascular mortality are modified by diabetes.

RESULTS

Individual participant-level data were analysed from 980 793 adults. During 9·8 million person-years of follow-up, among participants aged between 35 and 89 years, 19 686 (25·6%) of 76 965 deaths were attributed to occlusive vascular disease. After controlling for major vascular risk factors, diabetes roughly doubled occlusive vascular mortality risk among men (death rate ratio [RR] 2·10, 95% CI 1·97-2·24) and tripled risk among women (3·00, 2·71-3·33; χ2 test for heterogeneity p<0·0001). For both sexes combined, the occlusive vascular death RRs were higher in younger individuals (aged 35-59 years: 2·60, 2·30-2·94) than in older individuals (aged 70-89 years: 2·01, 1·85-2·19; p=0·0001 for trend across age groups), and, across age groups, the death RRs were higher among women than among men. Therefore, women aged 35-59 years had the highest death RR across all age and sex groups (5·55, 4·15-7·44). However, since underlying confounder-adjusted occlusive vascular mortality rates at any age were higher in men than in women, the adjusted absolute excess occlusive vascular mortality associated with diabetes was similar for men and women. At ages 35-59 years, the excess absolute risk was 0·05% (95% CI 0·03-0·07) per year in women compared with 0·08% (0·05-0·10) per year in men; the corresponding excess at ages 70-89 years was 1·08% (0·84-1·32) per year in women and 0·91% (0·77-1·05) per year in men. Total cholesterol, blood pressure, and BMI each showed continuous log-linear associations with occlusive vascular mortality that were similar among individuals with and without diabetes across both sexes.

INTERPRETATION

Independent of other major vascular risk factors, diabetes substantially increased vascular risk in both men and women. Lifestyle changes to reduce smoking and obesity and use of cost-effective drugs that target major vascular risks (eg, statins and antihypertensive drugs) are important in both men and women with diabetes, but might not reduce the relative excess risk of occlusive vascular disease in women with diabetes, which remains unexplained.

FUNDING

UK Medical Research Council, British Heart Foundation, Cancer Research UK, European Union BIOMED programme, and National Institute on Aging (US National Institutes of Health).

One-hour oral glucose tolerance test plasma glucose at gestational diabetes diagnosis is a common predictor of the need for insulin therapy in pregnancy and postpartum impaired glucose tolerance

Aims/Introduction

Gestational diabetes mellitus (GDM) is a risk for adverse perinatal outcomes, and patients with a history of GDM have an increased risk of impaired glucose tolerance (IGT). Here, we carried out two non‐interventional and retrospective studies of GDM patients in Japan.

Materials and Methods

In the first study, we enrolled 529 GDM patients and assessed predictors of the need for insulin therapy. In the second study, we enrolled 185 patients from the first study, and assessed predictors of postpartum IGT.

Results

In the first study, gestational weeks at GDM diagnosis and history of pregnancy were significantly lower, and pregestational body mass index, family history of diabetes mellitus, 1‐ and 2‐h glucose levels in a 75‐g oral glucose tolerance test (OGTT), the number of abnormal values in a 75‐g OGTT, and glycated hemoglobin were significantly higher in participants receiving insulin therapy. In the second study, 1‐ and 2‐h glucose levels in a 75‐g OGTT, the number of abnormal values in a 75‐g OGTT, glycated hemoglobin, and ketone bodies in a urine test were significantly higher in participants with OGT. Logistic regression analysis showed that gestational weeks at GDM diagnosis, 1‐h glucose levels in a 75‐g OGTT and glycated hemoglobin were significant predictors of the need for insulin therapy, and 1‐h glucose levels in a 75‐g OGTT at diagnosis and ketone bodies in a urine test were significant predictors for postpartum IGT.

Conclusions

Antepartum 1‐h glucose levels in a 75‐g OGTT was a predictor of the need for insulin therapy in pregnancy and postpartum IGT.

Endoplasmic reticulum stress responses in mouse models of Alzheimer's disease: Overexpression paradigm versus knockin paradigm

Endoplasmic reticulum (ER) stress is believed to play an important role in the etiology of Alzheimer's disease (AD). The accumulation of misfolded proteins and perturbation of intracellular calcium homeostasis are thought to underlie the induction of ER stress, resulting in neuronal dysfunction and cell death. Several reports have shown an increased ER stress response in amyloid precursor protein (APP) and presenilin1 (PS1) double-transgenic (Tg) AD mouse models. However, whether the ER stress observed in these mouse models is actually caused by AD pathology remains unclear. APP and PS1 contain one and nine transmembrane domains, respectively, for which it has been postulated that overexpressed membrane proteins can become wedged in a misfolded configuration in ER membranes, thereby inducing nonspecific ER stress. Here, we used an App-knockin (KI) AD mouse model that accumulates amyloid-β (Aβ) peptide without overexpressing APP to investigate whether the ER stress response is heightened because of Aβ pathology. Thorough examinations indicated that no ER stress responses arose in App-KI or single APP-Tg mice. These results suggest that PS1 overexpression or mutation induced a nonspecific ER stress response that was independent of Aβ pathology in the double-Tg mice. Moreover, we observed no ER stress in a mouse model of tauopathy (P301S-Tau-Tg mice) at various ages, suggesting that ER stress is also not essential in tau pathology-induced neurodegeneration. We conclude that the role of ER stress in AD pathogenesis needs to be carefully addressed in future studies.

Full-layer mucosal histology in achalasia: Histological epithelial wave is characteristic in "pinstripe pattern"-positive achalasia

BACKGROUND

Previously, the mucosal histology in achalasia has only been investigated using superficial biopsy or surgically resected esophageal specimens in end-stage cases. We investigated the histology of the full-layer mucosa in early and advanced achalasia.

METHODS

Endoscopy was performed for the pinstripe pattern (PSP) (an early achalasia indicator) and dilation and thickening of the mucosa (advanced achalasia indicators). A mucosal entry site for peroral endoscopic myotomy was created using cap-fitted endoscopic mucosal resection to access the full-layer mucosa and the submucosa.

KEY RESULTS

Mucosal histology was compared between 32 patients with achalasia and 15 controls. Histological esophagitis with findings of inflammatory cell infiltration and dilated intercellular spaces was observed more in patients with achalasia than in controls (87.5% vs 13.3%, P<.001; 84.4% vs 46.7%, P=.049). Muscularis mucosae (MM) atrophy and epithelial wave were only observed in achalasia (40.6% vs 0%, P=.005; 28.1% vs 0%, P=.043). Fibrosis was more common in achalasia, but without statistical significance (31.3% vs 20.0%, P=.503). In achalasia with endoscopic dilation and thickening of the mucosa, MM atrophy was observed histologically, and in cases involving endoscopic PSP, the histological epithelial wave was observed.

CONCLUSIONS & INFERENCES

Histological findings of esophagitis were observed endoscopically even in early achalasia. Pinstripe pattern corresponds to the epithelial wave observed histologically in achalasia, whereas endoscopic findings in advanced achalasia correspond to MM atrophy. Appropriate management is necessary during early achalasia to prevent progression to advanced achalasia with more severe histological changes.

Perioperative respiratory complications: current evidence and strategy discussed in 2017 JA symposium

Respiratory management during general anesthesia aims to safely secure the airway and maintain adequate ventilation to deliver oxygen to the vital organs, maintaining homeostasis even during surgery. Despite its clinical importance, anesthesiologists often encounter difficulties in properly managing respiration during the perioperative period, leading to severe respiratory complications. In this year's JA symposium, 5 editorial board members of Journal of Anesthesia (JA) who are experts in the field of respiratory management in anesthesia discussed the following topics: quitting smoking before surgery: exposure to passive smoke is damaging to children, ventilator-associated pneumonia, high inspiratory oxygen concentration and lung injury, aspiration pneumonia, and postoperative respiratory management strategy in patients with obstructive sleep apnea. We hope that this special article regarding this year's JA symposium may be useful for JA readers to manage clinical anesthesia on a daily basis.