Regional differences in the ultrastructure of mucosal macrophages in the rat large intestine

We previously clarified the histological characteristics of macrophages in the rat small intestine using serial block-face scanning electron microscopy (SBF-SEM). However, the regional differences in the characteristics of macrophages throughout the large intestine remain unknown. Here, we performed a pilot study to explore the regional differences in the ultrastructure of mucosal macrophages in the large intestine by using SBF-SEM analysis. SBF-SEM analysis conducted on the luminal side of the cecum and descending colon revealed macrophages as amorphous cells possessing abundant lysosomes and vacuoles. Macrophages in the cecum exhibited a higher abundance of lysosomes and a lower abundance of vacuoles than those in the descending colon. Macrophages with many intraepithelial cellular processes were observed beneath the intestinal superficial epithelium in the descending colon. Moreover, macrophages in contact with nerve fibers were more prevalent in the cecum than in the descending colon, and a subset of them surrounded a nerve bundle only in the cecum. In conclusion, the present pilot study suggested that the quantity of some organelles (lysosomes and vacuoles) in macrophages differed between the cecum and the descending colon and that there were some region-specific subsets of macrophages like nerve-associated macrophages in the cecum.

Quantification of the tissue distribution and accumulation of the neonicotinoid pesticide clothianidin and its metabolites in maternal and fetal mice

Neonicotinoids (NNs) are commonly used pesticides that have a selective agonistic action on insect nicotinic acetylcholine receptors. Recent evidence has shown that NNs have adverse effects in the next generation of mammals, but it remains unclear how NNs transferred from dams to fetuses are distributed and accumulated in fetal tissues. Here, we aimed to clarify the tissue distribution and accumulation properties of the NN clothianidin (CLO) and its 6 metabolites in 7 tissues and blood in both dams and fetuses of mice administered CLO for a single day or for 9 consecutive days. The results showed that the total concentrations of CLO-related compounds in the brain and kidney were higher in fetuses than in dams, whereas in the liver, heart, and blood they were lower in fetuses. The multi-day administration increased the total levels in heart and blood only in the fetuses of the single administration group. In addition, dimethyl metabolites of CLO showed fetus/dam ratios >1 in some tissues, suggesting that fetuses have higher accumulation property and are thus at higher risks of exposure to CLO-related compounds than dams. These findings revealed differences in the tissue-specific distribution patterns of CLO and its metabolites between dams and fetuses, providing new insights into the assessment of the developmental toxicity of NNs.

Direct diffusion of anti-Müllerian hormone from both the cranial and caudal regions of the testis during early gonadal development in mice

BACKGROUND

The Müllerian duct (MD), the primordium of the female reproductive tract, is also formed in males during the early stage of development, then regresses due to the anti-Müllerian hormone (AMH) secreted from the testes. However, the detailed diffusion pathway of AMH remains unclear. We herein investigated the mechanism by which AMH reaches the middle region of the MD using an organ culture system.

RESULTS

Injection of recombinant human AMH into the testis around the start of MD regression induced diffuse immunoreactivity in the mesonephros near the injection site. When the testis and mesonephros were cultured separately, the diameters of both cranial and middle MDs were significantly increased compared to the control. In the testis-mesonephros complex cultured by inhibiting the diffusion of AMH through the cranial region, the cranial MD diameter was significantly increased compared to the control, and there was no difference in middle MD diameter.

CONCLUSIONS

These results indicate that AMH, which infiltrates from the testis through the cranial region at physiological concentrations, induces regression of the cranial MD at the start of MD regression. They also indicate that AMH infiltrating through the caudal regions induces regression of the middle MD.

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.

Effects of exposure to the neonicotinoid pesticide clothianidin on mouse intestinal microbiota under unpredictable environmental stress

Recent research has demonstrated the toxicity of neonicotinoid pesticides (NNs) in mammals through their interaction with nicotinic acetylcholine receptors (nAChRs). These effects are reported to extend to the intestinal microbiota as well. In addition, environmental stress affects the expression of nAChRs, which may alter sensitivity to NNs. In this study, we analyzed the intestinal microbiota of mice exposed to clothianidin (CLO), a type of NN, under environmental stress, and aimed to clarify the effects of such combined exposure on the intestinal microbiota. C57BL/6N male mice (9 weeks old) were subchronically administered a no-observed-adverse-effect-level (NOAEL) CLO-mixed rehydration gel for 29 days and simultaneously subjected to chronic unpredictable mild stress (CUMS). After the administration period, cecum contents were collected and analyzed by 16S rRNA sequencing for intestinal microbiota. CLO exposure alone resulted in alterations in the relative abundance of Alistipes and ASF356, which produce short-chain fatty acids. The addition of CUMS amplified these changes. On the other hand, CLO alone did not affect the relative abundance of Lactobacillus, but the abundance decreased when CUMS was added. This study revealed that the combined exposure to CLO and stress not only amplifies their individual effects on intestinal microbiota but also demonstrates combined and multifaceted toxicities.

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.

Diurnal changes in bacterial settlement on the Peyer's patch and surrounding mucosa in the rat ileum and its effect against the intestinal immune system

Our previous study revealed the diurnal change in the indigenous bacteria settling on the terminal region of the rat ileum. In the present study, we investigated the diurnal change in indigenous bacteria on the most distal ileal Peyer's patch (PP) and surrounding ileal mucosa and explored how stimulation from indigenous bacteria for a day affects the intestinal immune system at the beginning of the light phase. Histological measurement revealed that bacteria adjacent to the follicle-associated epithelium of PP and to the villous epithelium of the surrounding ileal mucosa are more abundant at zeitgeber time (ZT)0 and ZT18 than at ZT12. On the other hand, tissue-section 16S rRNA amplicon sequencing revealed no significant difference between ZT0 and ZT12 in the bacterial composition on the ileal tissue including the PP. One-day treatment with an antibiotic (Abx) successfully impaired the settlement of bacteria around the ileal PP. In transcriptome analysis, 1-day Abx treatment led to the downregulation of several chemokines in both PP and ordinary ileal mucosa at ZT0. Histological analysis of the 1-day Abx group revealed decreases in both CD68⁺ macrophages in PP and naphthol AS-D chloroacetate esterase stain-positive mast cells in the ileal villi. Together, these findings suggest that the colonies of indigenous bacteria on the distal ileal PP and surrounding mucosa expand during the dark phase, which might lead to the expression of genes to regulate the intestinal immune system and contribute to the homeostasis of at least macrophages in PP and mast cells in the ileal mucosa.

Developmental stage-specific exposure and neurotoxicity evaluation of low-dose clothianidin during neuronal circuit formation

Neonicotinoid pesticides (NN) were recently reported to exhibit adverse effects in higher vertebrates. Moreover, NNs are routinely transferred from mother to offspring, raising concerns about their effects on future generations. The fetal and neonatal periods are the most critical to the formation of neural circuits in the brain through neurogenesis and differentiation, neuronal migration, axon guidance, and synaptogenesis. NN exposure throughout the fetal and neonatal periods was found to affect the neurobehavior of the offspring, but the stage-specific neurobehavioral effects are unclear. We exposed fetal and neonatal mice to a no-observed-adverse-effect level (NOAEL) of clothianidin (CLO) for 4 days during each of four developmental stages: neurite proliferation and differentiation (fetal days 9-12, CLO-1), neurite outgrowth (fetal days 15-18, CLO-2), synapse formation and astrocyte differentiation (days 1-4 after birth, CLO-3), and synapse remodeling (days 11-14 after birth, CLO-4). CLO's neurobehavioral effects were evaluated in juveniles and adults, revealing that CLO-1 and CLO-2 caused behavioral abnormalities in adult mice. CLO-3 significantly increased locomotor activity and decreased juvenile neurons in the hippocampal dentate gyrus in adulthood. Comprehensive gene analysis of CLO-3 revealed high expression of genes related to neurite outgrowth and axonal branching in the hippocampus in juveniles and adults. These results revealed developmental stage-specific effects of a NOAEL of CLO in the fetal and neonatal periods, suggesting that the susceptibility of the fetus and neonate to CLO varies by developmental stage.

Substrain differences in Sry expression at the stage of sex determination in C57BL/6 mouse strains

The expression of sex determining region of the Y chromosome (Sry) in the fetal gonads is important for male development. In a mouse model of disorders of sex development (C57BL/6 (B6)-XY^POS), the gonadal phenotype and the timing of Sry expression differ due to differences among the B6 substrain as the genetic background. Since differences in Sry expression among B6 substrains have been speculated, the present study examined Sry expression in B6J, B6JJmsSlc, and B6NCrl mice. These substrains differed in the number of Sry-expressing cells in the gonads of embryonic mice at each developmental stage, with B6NCrl having more than the other strains. The substrains differed also in the number of Sry-expressing cells between the left and right gonads, with B6J and B6NCrl, but not B6JJmsSlc, showing left gonad-dominant Sry expression. Substrain differences existed also in the distribution of Sry-expressing cells in the medial and lateral directions of gonads. In addition, in the left gonad-dominant Sry-expressing substrains B6J and B6NCrl, the medial and central regions of the left gonad had more Sry-expressing cells than those of the right gonad. Substrains of B6 mice have not always been considered in sex differentiation studies. In the present study, however, we observed substrain differences in the number of Sry-expressing cells, left-right distribution, and medial/lateral distribution during the early stages of gonadal development in B6 mice. Therefore, future studies on sex differentiation in B6 mice should consider substrain differences.

Next-generation effects of fetal and lactational exposure to the neonicotinoid pesticide clothianidin on the immune system and gut microbiota

Recently, the effects of exposure to clothianidin (CLO) on the thymus and gut microbiota have become clear, but no report has examined its next-generation impacts. Pregnant C57BL/6N mice were administered a no-observed-adverse-effect-level dose of CLO until weaning. We examined CLO's effects on the gut microbiota and immune organs of dams and their 3- and 10-week-old male offspring. CLO administration led to several alterations of the top 30 bacterial genera in the gut microbiota in dams and 3-week-old mice. Compared to controls, 10-week-old mice had more thymic Hassall's corpuscles, and both dams and 10-week-old mice had fewer macrophages. These results suggest that fetal and lactational CLO exposure may affect the immune system and gut microbiota of the next generation.

Histological study on regional specificity of the mucosal nerve network in the rat large intestine

Our previous studies and others have revealed detailed characteristics of the mucosal nerve network in the small intestine, but much remains unknown about the corresponding network in the large intestine. We herein investigated regional differences in the expression of neurochemical markers, the nerve network structure, and the cells in contact with nerve fibers by histological analysis using both immunohistochemistry and serial block-face scanning electron microscopy (SBF-SEM). Immunohistochemistry revealed that immunopositive structures for protein gene product 9.5, vasoactive intestinal peptide (VIP), calretinin and vesicular acetylcholine transporter were more prevalent in the lamina propria of the ascending colon than the cecum and descending colon (DC). There was no significant difference in the frequency of most neurochemical markers between the cecum and DC, but the frequencies of VIP⁺ structures were higher in the cecum than in the DC. SBF-SEM analysis showed that the nerve network structure was more developed on the luminal side of the DC than the cecum. The cells that nerve fibers abundantly contacted were subepithelial and lamina propria fibroblast-like cells and macrophages. In addition, nerve fibers in the cecum were in more frequent contact with immune cells such as macrophages and plasma cells than nerve fibers in the DC. Thus, the present histological analysis suggested that the mucosal nerve network in the large intestine possessed both regional universality and various specificities, and revealed the intimate relationship between the nerve network and immune cells, especially in the cecum.

Natural history of severe aortic stenosis in elderly heart failure patients who declined transcatheter aortic valve implantation

Background

Transcatheter aortic valve implantation (TAVI) is an established minimally invasive treatment for elderly patients with severe aortic stenosis (AS). Although it is a relatively minimally invasive procedure, many elderly patients cannot undergo TAVI due to advanced age, advanced dementia, significantly impaired ADL, or because the patient or family does not wish to undergo TAVI. In general, severe AS patients died 5 years after an angina attack, 3 years after syncope symptoms, and 2 years after heart failure symptoms. However, few studies have investigated the prognosis of elderly patients with severe AS who declined TAVI.

Purpose

This study aimed to comprehend the natural history of elderly severe AS patients who declined aortic valve intervention and identify risk factors for death in the TAVI era.

Methods

We retrospectively reviewed 2,786 echocardiographic data from our hospital between 2017 and 2021. We identified 504 patients with AS in the echocardiography database. The severe AS was defined by the following echocardiography parameters: peak aortic flow velocity ≥4.0 m/s, aortic valve mean gradient ≥40 mmHg, aortic valve area (AVA)&lt;1.0 cm2, or AVA index&lt;0.6 cm2/m2. Patients with mild and moderate AS and patients who underwent surgical or transcatheter aortic valve intervention were excluded. Eventually, 82 patients fulfilled the study criteria and were analyzed in this study. Clinical events were investigated, and Cox proportional hazards analysis was performed to elucidate risk factors for mortality.

Results

The mean age was 89±6 years, and 63 (77%) were women. AHA/ACC classification was Stage A/B/C/D: 0%/52.4%/39.0%/8.5%. As event occurrence, we detected 34 (41.5%) all-cause deaths, 41 (50.0%) major adverse cardiovascular events, 32 (39.0%) development of heart failure, 13 (15.9%) chest pain attacks, and 3 (3.7%) syncope. The time from diagnosis of severe AS to all-cause death was 227±273 days, and the 1-, 2-, and 3-year survival rates were 61.5%, 46.2%, and 36.9%, respectively. Of the heart failure-onset population, 16 (50.0%) were found to have severe AS on initial heart failure admission. The incidence of heart failure at 1, 2, and 3 years after diagnosis of severe AS was 60.1%, 56.7%, and 45.4%, respectively. The time from heart failure to death was 107±147 days. Cox proportional hazards analysis adjusted with age, sex, comorbidities revealed that dementia (HR 4.5, P=0.014) and Katz index &lt;5 (HR7.8, P=0.009) were independent risk factors for mortality.

Conclusions

Compared to the comprehension of the natural history of AS patients, the prognosis in severe AS patients who declined TAVI was extremely poor. Although the elderly patients did not have a high rate of angina attacks or syncope symptoms, probably due to their reduced ADL, the results suggest that dementia prevention and maintenance of exercise tolerance are essential since dementia and reduced ADL (Katz&lt;5) are independent risk factors for mortality.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): Clinical Research Promotion Foundation Reiwa 2 Michinari Hieda

Histological study of diurnal changes in bacterial settlement in the rat alimentary tract

The composition of fecal bacteria is reported to change throughout the day, whereas the circadian rhythmicity of indigenous bacteria that settle on the epithelium is mostly unknown. The present study aimed to clarify the diurnal changes in the settlement of indigenous bacteria in the rat alimentary tract using histological analysis. The settlement of indigenous bacteria on the mucosal epithelium throughout the day and the diurnal changes in settlement levels were observed in the esophagus, the nonglandular area of the stomach, and the ileum. The peak of zeitgeber time (ZT) in the settlement level differed by segment: ZT 12 in the esophagus, ZT 6 in the nonglandular area of the stomach, and ZT 0 in the ileum. Moreover, 16S rRNA amplicon sequencing using tissue sections revealed that the compositions of the indigenous bacteria in the ileum differed among ZT. In the intervillous spaces of the ileum, the formation level of the mucus layer, one of the most fundamental host defenses against bacteria, was lowest at ZT 0. Bacteria were preferentially adjacent to the villous epithelium in the area without coverage by the mucus layer at ZT 0. These findings collectively suggest that the settlement level and possibly the composition of the indigenous bacteria changed diurnally in various segments of the alimentary tract, and the formation of the mucus layer might be the most likely to lead to such diurnal changes in indigenous bacteria, at least in the ileum.

Elucidation of the neurological effects of clothianidin exposure at the no-observed-adverse-effect level (NOAEL) using two-photon microscopy in vivo imaging

Neonicotinoid pesticides (NNs) cause behavioral abnormalities in mammals, raising concerns about their effects on neural circuit activity. We herein examined the neurological effects of the NN clothianidin (CLO) by in vivo Ca²⁺ imaging using two-photon microscopy. Mice were fed the no-observed-adverse-effect-level (NOAEL) dose of CLO for 2 weeks and their neuronal activity in the primary somatosensory cortex (S1) was observed weekly for 2 weeks. CLO exposure caused a sustained influx of Ca²⁺ in neurons in the S1 2/3 layers, indicating hyperactivation of neurons. In addition, microarray gene expression analysis suggested the induction of neuroinflammation and changes in synaptic activity. These results demonstrate that exposure to the NOAEL dose of CLO can overactivate neurons and disrupt neuronal homeostasis.

Impact of hypertension on clinical outcome in patients treated with vascular endothelial growth factor inhibitors

Background

Vascular endothelial growth factor (VEGF) family is overexpressed in the tumor microenvironment and induces tumor angiogenesis.1 VEGF signaling pathway (VSP) inhibitors are essential therapeutic drugs for solid cancer patients.2 However, VSP inhibitors often provoke drug-specific anti-angiogenesis in normal tissues, which was referred to as on-target toxicity.2 Hypertension (HTN) is one of the most frequent adverse events caused by VSP inhibitors. A previous report demonstrated that VSP inhibitor-induced hypertension is a favorable prognostic factor, contrarily.3However, multiple VSP inhibitors are administered in various cancer types, and then the relation between VSP inhibitor-associated hypertension and clinical outcome is still controversial.

Purpose

The aim of this study is to elucidate the impacts of HTN and the timing of onset on clinical outcome during cancer therapy with VSP inhibitors.

Method

We reviewed 2,348 patients who were treated with VSP inhibitors from the LIFE Study database, consisting of 14 municipality-level information from claims data between 2016 and 2020. According to the timing of HTN onset mode, the patients were stratified into 3 groups; (1) new-onset HTN group (n=334): de novo development after VSP inhibitor administration, (2) pre-existing HTN group (n=1,363): existing HTN at baseline, including aggravation after VSP inhibitor initiation, and (3) no HTN group (n=651) (Figure 1). The time to treatment failure (TTF) was applied as a surrogate clinical indicator of overall survival. Event-free survival analysis with the log-rank test was conducted for time to first treatment failure amongst the 3 groups. In addition, Cox proportional hazard models adjusted with clinical characteristics were performed to investigate independent factors for TTF.

Results

In the event-free survival analysis, both the new-onset HTN and the pre-existing HTN were associated with prolongation of TTF, compared to the non-HTN (p&lt;0.001 and p&lt;0.001, respectively, by Bonferroni correction) (Figure 2). The New-onset HTN was significantly associated with longer TTF than pre-existing HTN (p&lt;0.001). In Cox proportional hazard model adjusted with age, sex, past medical history, primary cancer lesion, and type of VSP inhibitors, the new-onset HTN and the pre-existing HTN were independent favorable factors, compared to the non-HTN [new-onset HTN: Hazard ratio (HR) 0.62, 95% confidence interval (CI) 0.54 - 0.71, p&lt;0.001; and pre-existing HTN: HR 0.85, 95% CI 0.77 - 0.94, p&lt;0.005]. Moreover, the New-onset HTN was also a significant factor for longer TTF, compared to the pre-existing HTN [HR 0.72, 95% CI 0.64 - 0.82, p&lt;0.001].

Conclusion

In patients treated with VSP inhibitors, both new-onset and pre-existing HTN are independent factors for a favorable clinical outcome, especially new-onset HTN after VSP inhibitors administration.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Japan Society for the Promotion of Science (JSPS) Grants-in-Aid for Scientific Research (KAKENHI) Figure 1. Patient screening and enrollmentFigure 2. HTN & TTF

A multicenter cohort study of osimertinib compared with afatinib as first-line treatment for EGFR-mutated non-small-cell lung cancer from practical dataset: CJLSG1903

Background

FLAURA, the prospective trial of osimertinib as a first-line therapy compared with first-generation epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs), did not show superior survival benefit for osimertinib in either the subgroup of Asians or the subgroup with the L858R mutation. In addition, the superiority of osimertinib compared with second-generation EGFR-TKI is thus far unclear.

Patients and methods

We reviewed the clinical data of all consecutive patients who were treated with osimertinib or afatinib as first-line therapy between May 2016 and October 2019 from 15 institutions in Japan. We defined the groups based on first-line EGFR-TKI as the afatinib group and the osimertinib group. Outcomes included time to discontinuation of any EGFR-TKI (TD-TKI), overall survival (OS), and time to treatment failure, with propensity score analysis carried out as an exploratory analysis in the survival and subgroup analyses.

Results

A total of 554 patients were enrolled. Data on 326 patients in the osimertinib group, and 224 patients in the afatinib group were analyzed. TD-TKI adjusted by propensity score in the afatinib and osimertinib groups was 18.6 months (95% confidence interval 15.8 to 22.0) and 20.5 months (95% confidence interval 13.8 to not reached), respectively, without significant difference (P = 0.204). OS adjusted by propensity score favored the afatinib group with a significant difference (P = 0.018). Subgroup analysis with propensity score showed that patients with L858R and without brain metastasis had superior survival benefit with afatinib compared with osimertinib (P < 0.001).

Conclusions

TD-TKI in the afatinib group was not significantly prolonged compared with the osimertinib group in the practical data. In the exploratory analysis of patients with L858R-mutated non-small-cell lung cancer without brain metastasis, afatinib showed more benefit in OS over osimertinib.

•

The large-scale practical data of 550 patients who were treated with osimertinib or afatinib as first-line therapy were analyzed.

•

The superiority of osimertinib compared with afatinib could not be demonstrated in all populations.

•

Osimertinib therapy showed effectiveness in patients with brain metastasis.

•

Afatinib therapy showed potential benefit in patients with L858R mutation and without brain metastasis.

Ultrastructural and phenotypical diversity of macrophages in the rat ileal mucosa

Several types of macrophages have been reported in the intestinal mucosa, but their histological localization remains ambiguous. Here, we obtained detailed information about ultrastructural and phenotypical diversity of macrophage-like cells (MLCs) in the rat ileal mucosa using immunofluorescent analysis and serial block-face scanning electron microscopy (SBF-SEM). The results revealed that the cells immunopositive for CD68, the pan-macrophage marker, included CD163^-CD4⁺, CD163⁺CD4⁺, and CD163^-CD4^- cells in the lamina propria (LP) of the intestinal villus and around the crypt. CD68⁺CD4⁺CD163^- cells seemed to be preferentially localized in the intestinal villus, whereas CD68⁺CD163⁺CD4⁺ cells were frequently localized around the crypt. SBF-SEM analysis identified three types of MLCs in the ileal mucosa, which were tentatively named types I-III MLC based on aspects of the 3D-ultrastructure, such as the localization, quantity of lysosomes, endoplasmic reticulum, and exoplasm. Type I and II MLCs were localized in the villous LP, while type III MLCs were localized around the crypt, although type II MLCs were a minor population. All three MLC types extended their cellular processes into the epithelium, with type I MLCs showing the greatest abundance of extended processes. Type I MLCs in the upper portion of the intestinal villus showed a higher level of attachment to intraepithelial lymphocytes (IELs) compared to type III MLCs around the crypt. These findings suggest that macrophages of the rat ileal mucosa differed by region along the longitudinal axis of the villous tip-crypt from the perspective of ultrastructure, cellular composition, localization, and interactions with IELs.

Aging-related changes in the sensitivity of behavioral effects of the neonicotinoid pesticide clothianidin in male mice

Neonicotinoids, which act as agonists of the nicotinic acetylcholine receptors of insects, are widely used pesticides worldwide. Although epidemiological studies revealed that the detection amounts of neonicotinoids in urine are higher in the elderly population than other age-groups, there is no available information regarding the risks of neonicotinoids to older mammals. This study was aimed to investigate aging-related differences in the behavioral effects of the neonicotinoid pesticide clothianidin (CLO). We acutely administered a sub-NOAEL level (5 mg/kg) of CLO to adult (12-week-old) and aging (90-week-old) mice and conducted four behavioral tests focusing on the emotional behavior. In addition, we measured the concentrations of CLO and its metabolites in blood, brain and urine. There were age-related changes in most parameters in all behavioral tests, and CLO significantly decreased the locomotor activity in the open field test and elevated plus-maze test in the aging group, but not in the adult group. The concentrations of most CLO and its metabolites were significantly higher in the blood and brain and were slightly lower in the urine in the aging group compared to the adult group. These findings should contribute to our understanding of age-related differences in the adverse effects of neonicotinoids in mammals.

Fetal and lactational exposure to the no-observed-adverse-effect level (NOAEL) dose of the neonicotinoid pesticide clothianidin inhibits neurogenesis and induces different behavioral abnormalities at the developmental stages in male mice

Recently, it has been reported that neonicotinoid pesticides (NNs) are transferred from mother to child and are assumed to affect the next generation, but the behavioral effects of NN exposure at different developmental stages have not been investigated. We exposed mice to no-observed-adverse-effect level (NOAEL) doses of clothianidin (CLO) during the fetal and lactational period, and then evaluated the neurobehavioral effects in juvenile and adult mice. Significant increases in anxiety-like behavior and locomotor activity were observed in juveniles and adults, respectively, and neuronal activity and neurogenesis in the hippocampal dentate gyrus were affected in both stages. These results suggest that fetal and lactational exposure to CLO may inhibit neurogenesis and cause different behavioral abnormalities at different developmental stages.

Influence of acute exposure to a low dose of systemic insecticide fipronil on locomotor activity and emotional behavior in adult male mice

Fipronil (FPN) is a systemic insecticide that antagonizes the gamma-aminobutyric acid type A (GABA_A) receptors in insects. Recently, adverse effects of FPN on mammals have been reported, but most of those were caused by high doses of FPN and additives in the products. We investigated the effects of low-dose pure FPN on the emotional behavior of mice. Nine-week-old male mice conducted behavioral tests 24 hr after FPN administration by gavage at doses of 0.05 or 5 mg/kg based on the no-observed-effect level (NOEL), showed a significant increase in locomotor activity and dose-dependent responses on the time they spent in the central zone in the open field test. Pure FPN below the NOEL dose may affect the emotional behavior of mice.

Daytime Dynamo Electrodynamics With Spiral Currents Driven by Strong Winds Revealed by Vapor Trails and Sounding Rocket Probes

We investigate the forces and atmosphere-ionosphere coupling that create atmospheric dynamo currents using two rockets launched nearly simultaneously on 4 July 2013 from Wallops Island (USA), during daytime Sq conditions with ΔH of -30 nT. One rocket released a vapor trail observed from an airplane which showed peak velocities of >160 m/s near 108 km and turbulence coincident with strong unstable shear. Electric and magnetic fields and plasma density were measured on a second rocket. The current density peaked near 110 km exhibiting a spiral pattern with altitude that mirrored that of the winds, suggesting the dynamo is driven by tidal forcing. Such stratified currents are obscured in integrated ground measurements. Large electric fields produced a current opposite to that driven by the wind, believed created to minimize the current divergence. Using the observations, we solve the dynamo equation versus altitude, providing a new perspective on the complex nature of the atmospheric dynamo.

Three-dimensional analysis of neural connectivity with cells in rat ileal mucosa by serial block-face scanning electron microscopy

The comprehensive targets of innervation in the intestinal mucosa are unknown, partly because of the diversity of cell types and the complexity of the neural circuits. Herein, we investigated the comprehensive targets of neural connectivity and analyzed the precise characteristics of their contact structures in the mucosa of rat ileum. We examined target cells of neural connections and the characteristics of their contact structures by serial block-face scanning electron microscopy at four portions of the rat ileal mucosa: the apical and basal portions in the villi, and the lateral and basal portions around/in the crypts. Nerve fibers were in contact with several types of fibroblast-like cells (FBLCs), macrophage-like cells, eosinophils, lymphocyte-like cells, and other types of cells. The nerve fibers almost always ran more inside of lamina propria than subepithelial FBLC, and thus contacts with epithelial cells were very scarce. The contact structures of the nerve fibers were usually contained synaptic vesicle-like structures, and we classified them into patterns based on the number of nerve fiber contacting the target cells at one site, the maximum diameter of the contact structures, and the relationship between nerve fibers and nerve bundles. The contact structures for each type of cells occasionally dug into the cellular bodies of the target cells. We revealed the comprehensive targets of neural connectivity based on the characteristics of contact structures, and identified FBLCs, immunocompetent cells, and eosinophils as the candidate targets for innervation in the rat ileal mucosa.

Establishment of an organ culture system to induce Sertoli cell differentiation from undifferentiated mouse gonads

Organ culture systems are useful for elucidating the process of testicular differentiation from mammalian undifferentiated genetically male gonads, as they permit various experiments, including experiments involving the control of gene expression. However, without addition of testicular differentiation-related factors, it is difficult to induce the formation of testis cord from immature gonads by a time point earlier 12 tail somites (ts) that corresponding to 11.0 days post coitum (dpc). In this study, we attempted to establish an organ culture system that induces testis formation from immature gonads (around 8 ts: 10.5 dpc) just before Sry (sex-determining region of the Y chromosome) expression. A paired gonad-mesonephros complex of around 8 ts was placed in the groove of an agarose gel block and put the semi-cylindrical piece of agarose gel to maintain the gonad morphology. The gonads were cultured in the gas phase for 96 hr. As a result, testis cord-like structures appeared in many genetically male gonads. Cells expressing the Sertoli cell markers Sox9 (SRY-box 9) and Amh (anti-Müllerian hormone) were observed, while granulosa cell marker Foxl2 (forkhead box L2) was not detected. In addition, Sox9- and Amh-expressing cells were observed throughout the entire gonad in many individuals. Amh mRNA expression was also upregulated. Surprisingly, formation of a partial testicular structure was observed from more immature gonads (6 ts). These results show that our gonadal organ culture system is useful for elucidating the regulation mechanism of Sry expression in undifferentiated bipotential gonads.

Immunotoxicity evaluation by subchronic oral administration of clothianidin in Sprague-Dawley rats

Neonicotinoid pesticides (NNs) act as agonists on nicotinic acetylcholine receptors (nAChRs) of insects, and there have been concerns about the effects of NNs on the health of mammals. Since nAChRs are expressed in immune cells, it is possible that NNs disturb the immune system. However, few reports have examined the immunotoxicity of clothianidin (CLO), a widely-used NN. Here, we report the effects of CLO on immune organs and type IV allergic reactions in ear auricles. We orally administered CLO at 0, 30 and 300 mg/kg/day (CLO-0, 30 and 300) to Sprague-Dawley rats for 28 days. The effects were evaluated by organ and body weights, histopathology, and immunohistochemistry (TCRαβ, CD4, CD8, CD11b, CD68, CD103). In addition, some cecal contents were subjected to preliminary gut microbiota analysis, because microbiota contribute to host homeostasis, including the immunity. Our results showed loose stool, suppression of body weight gain, significant changes in organ weights (thymus: decreased; liver: increased) and changes of the gut microbiota in the CLO-300 group. There were no obvious histopathological changes in immune organs. Granulomas of the ear auricles were found in one rat of each of the CLO-30 and 300 groups, but CLO had no apparent effect on the thickness or immunohistochemistry in the ear auricles. We present new evidence that CLO affects the thymus and intestine, and might enhance the local inflammatory response. These findings should contribute to the appropriate evaluation of the safety of NNs in the future.

Combined exposure to dinotefuran and chronic mild stress counteracts the change of the emotional and monoaminergic neuronal activity induced by either exposure singly despite corticosterone elevation in mice

Dinotefuran (DIN) belongs to the neonicotinoids (NNs), a class of globally applied pesticides originally developed to exhibit selective toxicity in insects. However, several reports have suggested that NNs also exert neurotoxic effects in mammals. We previously demonstrated neurobehavioral effects of DIN on mice under non-stressful conditions. For further toxicity assessments in the present study, we investigated the effects of DIN on mice exposed to stressful conditions. After subacutely administering a no-observed-effect-level (NOEL) dose of DIN and/or chronic unpredictable mild stress (CUMS) to mice, we conducted three behavioral tests (i.e., open field test [OFT], tail suspension test [TST] and forced swimming test [FST]). In addition, serotonin (5-HT) and tryptophan hydroxylase 2 (TPH2) of the dorsal raphe nuclei (DRN) and median raphe nuclei (MRN) and tyrosine hydroxylase (TH) of the ventral tegmental area and substantia nigra (SN) were evaluated immunohistochemically. A NOEL dose of DIN or CUMS alone increased of the total distance in OFT, decreased or increased the immobility time in TST or FST, respectively, and increased the positive intensity of 5-HT and TPH2 in the DRN/MRN, and TH in the SN. These changes were suppressed under the conditions of combined exposure to DIN and CUMS, though the blood corticosterone level was increased depending on the blood DIN values and the presence of CUMS. The present study suggests the multifaceted toxicity of the neurotoxin DIN.

Quantitative elucidation of maternal-to-fetal transfer of neonicotinoid pesticide clothianidin and its metabolites in mice

Neonicotinoids (NNs), a widely used class of systemic pesticides, are regarded as exhibiting selective toxicity in insects. However, NNs are suspected of exerting adverse effects on mammals as well, including humans. To date, only adult male animal models have been subjected to general toxicity studies of NNs; fetuses have yet to be considered in this context. Here, we focused on the NN clothianidin (CLO) for the first quantitative LC-MS/MS analysis of maternal-to-fetal transfer and residual property of once-daily (single or multiple days), orally administered CLO and its metabolites in mice. The results revealed the presence of CLO and its five metabolites at approximately the same respective blood levels in both dams and fetuses. In the dams, CLO showed a peak value 1 h after administration, after which levels rapidly decreased at 3 and 6 h. In the fetuses of each group, levels of CLO were almost the same as those observed in the corresponding dams. The present results clearly demonstrated rapid passage of CLO through the placental barrier. However, metabolite-dependent differences observed in blood pharmacokinetics and residual levels. This is the first quantitative demonstration of the presence of CLO and its metabolites in fetal mouse blood.

A self-reported measurement scale on a potential component of competency in the healthcare staff engaged in the prevention and control of non-communicable disease in Fiji

Background

According to the World Health Organization, an estimated 80% or more deaths in Pacific island countries, including Fiji, were related to non-communicable diseases (NCDs). Although competency-based approaches have been effective for developing healthcare workers’ capabilities, there are only a few reports on competency scales of healthcare workers for NCD prevention. We aimed to develop a self-reported measurement scale on a potential component of competency in the healthcare staff engaged in the prevention and control of NCDs in Fiji.

Methods

There were 378 Ministry of Health and Medical Services staff members working on NCD prevention and control in Fiji included in this study, which was a cross-sectional survey of social factors, working situation factors, and competency. Exploratory factor analysis was conducted to assess potential competency components, whereas Cronbach’s α coefficient and analysis of variance were used to assess the validity and reliability of the scale items, respectively. Multivariate regression analyses were conducted to analyze the respondents’ factor scores relative to social status and work situations.

Results

The factor analysis revealed 16 items that identified competency in four work types: 1) work management, 2) monitoring and evaluation, 3) community partnership, and 4) community diagnosis. The monitoring and evaluation roles were related to ethnic background, community partnership was related to religion, and community diagnosis was related to academic qualifications.

Conclusions

Based on the results, we developed a competency scale for the four work types. This scale can help healthcare workers engage in better management of residents with NCDs in Fiji.

Retinoic acid-stimulated ERK1/2 pathway regulates meiotic initiation in cultured fetal germ cells

In murine fetal germ cells, retinoic acid (RA) is an extrinsic cue for meiotic initiation that stimulates transcriptional activation of the Stimulated by retinoic acid gene 8 (Stra8), which is required for entry of germ cells into meiotic prophase I. Canonically, the biological activities of RA are mediated by nuclear RA receptors. Recent studies in somatic cells found that RA noncanonically stimulates intracellular signal transduction pathways to regulate multiple cellular processes. In this study, using a germ cell culture system, we investigated (1) whether RA treatment activates any mitogen-activated protein kinase (MAPK) pathways in fetal germ cells at the time of sex differentiation, and (2) if this is the case, whether the corresponding RA-stimulated signaling pathway regulates Stra8 expression in fetal germ cells and their entry into meiosis. When XX germ cells at embryonic day (E) 12.5 were cultured with RA, the extracellular-signal-regulated kinase (ERK) 1/2 pathway was predominantly activated. MEK1/2 inhibitor (U0126) treatment suppressed the mRNA expressions of RA-induced Stra8 and meiotic marker genes (Rec8, Spo11, Dmc1, and Sycp3) in both XX and XY fetal germ cells. Furthermore, U0126 treatment dramatically reduced STRA8 protein levels and numbers of meiotic cells among cultured XX and XY fetal germ cells even in the presence of RA. Taken together, our results suggest the novel concept that the RA functions by stimulating the ERK1/2 pathway and that this activity is critical for Stra8 expression and meiotic progression in fetal germ cells.

Growth and neurite stimulating effects of the neonicotinoid pesticide clothianidin on human neuroblastoma SH-SY5Y cells

Neonicotinoids are one of most widely used pesticides targeting nicotinic acetylcholine receptors (nAChRs) of insects. Recent epidemiological evidence revealed increasing amounts of neonicotinoids detected in human samples, raising the critical question of whether neonicotinoids affect human health. We investigated the effects of a neonicotinoid pesticide clothianidin (CTD) on human neuroblastoma SH-SY5Y cells as in vitro models of human neuronal cells. Cellular and functional effects of micromolar doses of CTD were evaluated by changes in cell growth, intracellular signaling activities and gene expression profiles. We examined further the effects of CTD on neuronal differentiation by measuring neurite outgrowth. Exposure to CTD (1-100 μM) significantly increased the number of cells within 24 h of culture. The nAChRs antagonists, mecamylamine and SR16584, inhibited this effect, suggesting human α3β4 nAChRs could be targets of neonicotinoids. We observed a transient intracellular calcium influx and increased phosphorylation of extracellular signal-regulated kinase 1/2 shortly after exposure to CTD. Transcriptome analysis revealed that CTD down-regulated genes involved in neuronal function (e.g., formation of filopodia and calcium ion influx) and morphology (e.g., axon guidance signaling and cytoskeleton signaling); these changes were reflected by a finding of increased neurite length during neuronal differentiation. These findings provide novel insight into the potential risks of neonicotinoids to the human nervous system.

Genetic differences between C57BL/6 substrains affect the process of testis differentiation in YPOS mice

C57BL/6J-XY^POS (B6J-XY^POS) mice, which have the Y chromosome derived from Mus musculus poschiavinus on a B6J genetic background, form ovotestes or ovaries. Previously, we replaced the genetic background of B6J-XY^POS mice with B6N and found that individuals with testes also appeared in addition to those with ovaries or ovotestes. To investigate the effect of the B6J genetic sequence on the testis differentiation, the genetic background of B6N-XY^POS mice was replaced with B6J again. The recovery of the B6J genetic background significantly decreased the incidence of testes; only ovaries developed. These results indicate that the testicular differentiation process tends to be perturbed especially in the B6J substrain. This shows the importance of substrain differences in mice usually treated as B6 collectively.