Clinicoepidemiological Profile of Ciguatera Cardiotoxicity: A Systematic Review

Patients with ciguatera poisoning commonly present with gastrointestinal and neurologic symptoms, but its cardiotoxicity has been largely unrecognized. This systematic review is the first to summarize the evidence regarding clinical characteristics of cardiotoxicity from ciguatera poisoning to provide the illness script and pertinent knowledge for clinicians. Following the Preferred Reporting Items for Systematic reviews and Meta-Analyses statement, we searched MEDLINE and EMBASE for all peer-reviewed articles using keywords including "ciguatera" and "cardiotoxicity" from their inception to January 2024. We included 20 articles, including 148 cases, in this systematic review. Among the included cases, the median age was 54 years with male predominance (62.2%). Based on the WHO designation, 68.5% were reported from the Western Pacific Region. Common symptoms included hypotension (75.0%) and bradycardia (67.6%), and chest pain or syncope were less commonly reported (2.7% and 1.4%, respectively). Sinus bradycardia was the most common electrocardiogram abnormality (35.9%), followed by atrioventricular blocks (15.4%). Symptomatic treatments such as atropine, dopamine, and epinephrine were commonly used, and only 4.1% required intensive care unit admission. None expired due to cardiotoxicity from ciguatera. This review summarizes the current evidence and the characteristics of cardiotoxicity from ciguatera. Although ciguatera cardiotoxicity is currently underrecognized, increased awareness of the condition in clinicians is crucial because the clinical outcomes of the patients could be benign as long as it is identified and intervened early.

Bilateral Renal Vein Thrombosis and Chylous Ascites in Phospholipase A2 Receptor-Associated Membranous Nephropathy: A Case Report

Phospholipase A2 receptor (PLA2R)-associated membranous nephropathy is an important cause of nephrotic syndrome that can lead to a variety of systemic manifestations. Chylous ascites and bilateral renal vein thrombosis are rare manifestations in adult nephrotic syndrome, and there have been no reported cases demonstrating both chylous ascites and bilateral renal vein thrombosis in patients with PLA2R-associated membranous nephropathy. Here, we report the first case of PLA2R-associated membranous nephropathy complicated by renal vein thrombosis and chylous ascites successfully treated with anticoagulation and rituximab. A 65-year-old African American male presented with abdominal pain for four days, hematochezia for one day, and lower extremity edema for one year. Blood pressure was 158/73 mmHg and other vital signs were normal. Physical examination revealed abdominal distention, periumbilical tenderness, and bilateral lower extremity edema. Laboratory analysis showed high serum creatinine, hypoalbuminemia, hyperlipidemia, and proteinuria on 24-hour urine chemistry, all consistent with nephrotic syndrome. Abdominal computed tomography scan demonstrated nonocclusive bilateral renal vein thrombosis with ascites. Paracentesis revealed chylous ascites. Continuous heparin infusion was started for thrombosis. Esophagoduodenoscopy and colonoscopy did not reveal a source of bleeding. Serum anti-PLA2R was found positive, suggesting membranous nephropathy. Rituximab, along with warfarin switched from heparin, successfully controlled disease activity. Chylous ascites in nephrotic syndrome is thought to be associated with bowel edema. In our case, we hypothesize that renal vein thrombosis caused lymphatic fluid leakage by increasing lymphatic pressure. The case illustrates the importance of considering membranous nephropathy as a cause of chylous ascites and renal vein thrombosis. Development of lymphatic imaging techniques is warranted to clarify the pathophysiology.

Airway epithelial cell identity and plasticity are constrained by Sox2 during lung homeostasis, tissue regeneration, and in human disease

Maintenance of the cellular boundary between airway and alveolar compartments during homeostasis and after injury is essential to prohibit pathological plasticity which can reduce respiratory function. Lung injury and disease can induce either functional alveolar epithelial regeneration or dysplastic formation of keratinized epithelium which does not efficiently contribute to gas exchange. Here we show that Sox2 preserves airway cell identity and prevents fate changes into either functional alveolar tissue or pathological keratinization following lung injury. Loss of Sox2 in airway epithelium leads to a loss of airway epithelial identity with a commensurate gain in alveolar and basal cell identity, in part due to activation of Wnt signaling in secretory cells and increased Trp63 expression in intrapulmonary basal-like progenitors. In idiopathic pulmonary fibrosis, loss of SOX2 expression correlates with increased WNT signaling activity in dysplastic keratinized epithelium. SOX2-deficient dysplastic epithelial cells are also observed in COVID-19 damaged lungs. Thus, Sox2 provides a molecular barrier that suppresses airway epithelial plasticity to prevent acquisition of alveolar or basal cell identity after injury and help guide proper epithelial fate and regeneration.

Ramucirumab plus FOLFIRI as second-line treatment for patients with RAS wild-type metastatic colorectal cancer previously treated with anti-EGFR antibody: JACCRO CC-16

BACKGROUND

Chemotherapy in combination with anti-epidermal growth factor receptor (EGFR) antibody is considered a first-line treatment regimen for RAS wild-type and left-sided metastatic colorectal cancer (mCRC), whereas second-line treatment regimens have not yet been established. Few studies have prospectively evaluated second-line treatment with anti-vascular endothelial growth factor antibody after first-line anti-EGFR antibody therapy for RAS wild-type mCRC.

PATIENTS AND METHODS

This non-randomized phase II trial investigated the clinical outcomes of second-line ramucirumab (RAM) plus fluorouracil, levofolinate, and irinotecan (FOLFIRI) after first-line anti-EGFR antibody in combination with doublet or triplet regimen in patients with RAS wild-type mCRC. The primary endpoint was the 6-month progression-free survival (PFS) rate. The secondary endpoints were PFS, overall survival (OS), objective response rate (ORR), rate of early tumor shrinkage (ETS), and safety. We hypothesized a threshold 6-month PFS rate of 30% and an expected 6-month PFS rate of 45%. Treatment was considered effective if the lower limit of the 90% confidence interval (CI) of the 6-month PFS rate was >0.30.

RESULTS

Ninety-two patients were enrolled in the study. The primary tumor was located on the left side in 86 (95.6%) patients. Twenty (22.0%) patients had received triplet plus cetuximab as previous therapy. Six-month PFS rate was 58.2% (90% CI 49.3% to 66.2%) with a median PFS of 7.0 months (95% CI 5.7-7.6 months). Median OS was 23.6 months (95% CI 16.5-26.3 months). The ORR and ETS rate were 10.7% and 16.9%, respectively, in 83 patients with measurable lesions. The 6-month PFS rate was comparable between patients previously treated with doublet and triplet regimens; however, median PFS was longer for the doublet regimen (7.4 versus 6.4 months, P = 0.036).

CONCLUSIONS

Our study demonstrated prospectively that RAM plus FOLFIRI is an effective second-line treatment after anti-EGFR antibody-containing first-line therapy in RAS wild-type and left-sided mCRC. Furthermore, the results were similar for patients who were previously treated with triplet regimen.

DOT1L regulates lung developmental epithelial cell fate and adult alveolar stem cell differentiation after acute injury

AT2 cells harbor alveolar stem cell activity in the lung and can self-renew and differentiate into AT1 cells during homeostasis and after injury. To identify epigenetic pathways that control the AT2-AT1 regenerative response in the lung, we performed an organoid screen using a library of pharmacological epigenetic inhibitors. This screen identified DOT1L as a regulator of AT2 cell growth and differentiation. In vivo inactivation of Dot1l leads to precocious activation of both AT1 and AT2 gene expression during lung development and accelerated AT1 cell differentiation after acute lung injury. Single-cell transcriptome analysis reveals the presence of a new AT2 cell state upon loss of Dot1l, characterized by increased expression of oxidative phosphorylation genes and changes in expression of critical transcription and epigenetic factors. Taken together, these data demonstrate that Dot1l controls the rate of alveolar epithelial cell fate acquisition during development and regeneration after acute injury.

Biophysical forces mediated by respiration maintain lung alveolar epithelial cell fate

Lungs undergo mechanical strain during breathing, but how these biophysical forces affect cell fate and tissue homeostasis are unclear. We show that biophysical forces through normal respiratory motion actively maintain alveolar type 1 (AT1) cell identity and restrict these cells from reprogramming into AT2 cells in the adult lung. AT1 cell fate is maintained at homeostasis by Cdc42- and Ptk2-mediated actin remodeling and cytoskeletal strain, and inactivation of these pathways causes a rapid reprogramming into the AT2 cell fate. This plasticity induces chromatin reorganization and changes in nuclear lamina-chromatin interactions, which can discriminate AT1 and AT2 cell identity. Unloading the biophysical forces of breathing movements leads to AT1-AT2 cell reprogramming, revealing that normal respiration is essential to maintain alveolar epithelial cell fate. These data demonstrate the integral function of mechanotransduction in maintaining lung cell fate and identifies the AT1 cell as an important mechanosensor in the alveolar niche.

Search for the Majorana Nature of Neutrinos in the Inverted Mass Ordering Region with KamLAND-Zen

The KamLAND-Zen experiment has provided stringent constraints on the neutrinoless double-beta (0νββ) decay half-life in ^{136}Xe using a xenon-loaded liquid scintillator. We report an improved search using an upgraded detector with almost double the amount of xenon and an ultralow radioactivity container, corresponding to an exposure of 970 kg yr of ^{136}Xe. These new data provide valuable insight into backgrounds, especially from cosmic muon spallation of xenon, and have required the use of novel background rejection techniques. We obtain a lower limit for the 0νββ decay half-life of T_{1/2}^{0ν}>2.3×10^{26}  yr at 90% C.L., corresponding to upper limits on the effective Majorana neutrino mass of 36-156 meV using commonly adopted nuclear matrix element calculations.

It takes a lot of nerve to form the lung alveolus

Autonomic nerves innervate the lungs, but how these nerves guide lung development remains unclear. In this issue of Developmental Cell, Zhang et al. reveal that myofibroblasts and developing nerves cross-communicate through neurotrophins and neurotransmitters to drive alveologenesi-and that planar cell polarity signaling is critical to this process.

Microstructured Hydrogels to Guide Self-Assembly and Function of Lung Alveolospheres

Epithelial cell organoids have increased opportunities to probe questions on tissue development and disease in vitro and for therapeutic cell transplantation. Despite their potential, current protocols to grow these organoids almost exclusively depend on culture within 3D Matrigel, which limits defined culture conditions, introduces animal components, and results in heterogenous organoids (i.e., shape, size, composition). Here, a method is described that relies on hyaluronic acid hydrogels for the generation and expansion of lung alveolar organoids (alveolospheres). Using synthetic hydrogels with defined chemical and physical properties, human-induced pluripotent stem cell (iPSC)-derived alveolar type 2 cells (iAT2s) self-assemble into alveolospheres and propagate in Matrigel-free conditions. By engineering predefined microcavities within these hydrogels, the heterogeneity of alveolosphere size and structure is reduced when compared to 3D culture, while maintaining the alveolar type 2 cell fate of human iAT2-derived progenitor cells. This hydrogel system is a facile and accessible system for the culture of iPSC-derived lung progenitors and the method can be expanded to the culture of primary mouse tissue derived AT2 and other epithelial progenitor and stem cell aggregates.

POS0687 INHIBITION OF BONE EROSION, DETERMINED BY HIGH-RESOLUTION PERIPHERAL QUANTITATIVE COMPUTED TOMOGRAPHY (HR-pQCT), IN RHEUMATOID ARTHRITIS PATIENTS RECEIVING A CONVENTIONAL SYNTHETIC DMARD (csDMARD) PLUS DENOSUMAB VS csDMARD THERAPY ALONE: RESULTS OF AN OPEN-LABEL, RANDOMIZED, PARALLEL-GROUP STUDY

Background

Denosumab, a human IgG2 monoclonal antibody with high affinity for RANKL, is approved for treatment of bone erosion (ER) in patients with RA, based on the results of clinical trials. However, its effectiveness in combination with conventional therapy in RA patients has not been fully investigated in clinical practice.

Objectives

This exploratory study aimed to compare, in patients receiving conventional synthetic disease-modifying anti-rheumatic drugs (csDMARD) for treatment of RA, the effectiveness of combined use of csDMARD and denosumab vs csDMARD alone, in terms of inhibition of ER determined by HR-pQCT.

Methods

Detail protocol of this open-label, randomized, parallel-group study has been published previously.1 RA patients with moderate or low disease activity and progressive ER were eligible, and were randomly assigned to receive denosumab in addition to the csDMARD (denosumab) group or to continued use of the csDMARD alone (csDMARD) group. Denosumab was administered every 6 months during the 12-month study period. The primary endpoint was change in ER-depth at the second and third metacarpal bones, determined by HR-pQCT at month 6. For the primary endpoint, a linear mixed effect model analysis was performed using treatment group, sex, anti-cyclic citrullinated peptide (CCP) antibody (positive vs negative), and baseline disease activity (DAS28-ESR) as fixed effects, patients as random effects, and baseline values as covariates. For extension data, measurement time-point and the interaction between treatment group and measurement time-point was further added as fixed effects. The adverse events (AEs) were recorded.

Results

A total of 46 patients were randomized to denosumab and csDMARD groups (both N=23), and baseline characteristics were similar between both groups. Although the difference was not significant, the estimate mean (95%CI) change of ER-depth at month 6 from baseline as the primary endpoint was −0.57 (−1.52, 0.39) in the denosumab group vs −0.22 (−0.97, 0.53) in the csDMARD group, respectively. At months 6 and 12, ER-depth, -width, and -volume (extension data) were numerically lower in the denosumab group than in the csDMARD group (Table 1). Compared with patients in the csDMARD group, those in the denosumab group had significantly higher volumetric bone mineral density (vBMD) at month 12. AEs were reported in 12 (52.2%) and 13 (56.5%) of patients in the denosumab and csDMARD groups, respectively. The most common AEs of denosumab groups was hypocalcemia (reported in 4), and all the events were causally related with denosumab. Serious AEs were reported in 1 (4.3%) and 2 (8.7%) of patients in the denosumab and csDMARD groups, and which were not related to treatment drug.

Table 1.

ER and microstructure in denosumab group vs csDMARD group

MonthDenosumab group (n=21)csDMARDs group (n=22)Difference (Denosumab- csDMARDs)n1Estimate Means [95%CI]n1Estimate Means [95%CI]Estimate Means [95%CI]ER-depth617−0.46 [−1.31, 0.39]25−0.20 [−0.89, 0.49]−0.27 [−0.86, 0.32]1217−0.56 [−1.41, 0.29]22−0.20 [−0.90, 0.49]−0.35 [−0.95, 0.24]ER-width617−0.26 [−1.10, 0.57]25−0.06 [−0.73, 0.61]−0.20 [−0.81, 0.40]1217−0.27 [−1.10, 0.56]22−0.03 [−0.70, 0.64]−0.24 [−0.85, 0.38]ER-volume616−6.21 [−23.89, 11.46]24−1.71 [−16.07, 12.66]−4.51 [−16.67, 7.65]1217−6.25 [−23.94, 11.44]21−3.18 [−17.56, 11.20]−3.07 [−15.32, 9.17]vBMD6426.41 [2.78, 10.03]442.46 [−1.33, 6.24]3.95 [−0.05, 7.94]12389.20 [5.46, 12.95]423.66 [−0.15, 7.46]5.55 [1.46, 9.63]*

These were extension data.

This is the efficacy analysis set which excluded 3 patients from the full analysis set.

*; p<0.01

n, number of patients; n1, number of measurement points

Conclusion

Our results suggest that adding denosumab to csDMARD therapy may help prevent ER, promote ER repair, and improve bone microstructure.

References

[1]Iwamoto N, et al., Trials. 2019;20(1):1–8.

Disclosure of Interests

Naoki Iwamoto Speakers bureau: Daiichi Sankyo Co., Ltd., Grant/research support from: Daiichi Sankyo Co., Ltd., Ko Chiba Speakers bureau: Daiichi Sankyo Co., Ltd., Shuntaro Sato: None declared, Kazuteru Shiraishi: None declared, Konosuke Watanabe: None declared, Nozomi Ohki: None declared, Akitomo Okada: None declared, Tomohiro Koga: None declared, Makiko Kobayashi Employee of: Daiichi Sankyo Co., Ltd. (retired at submission), Kengo Saito Employee of: Daiichi Sankyo Co., Ltd., Naoki Okubo Employee of: Daiichi Sankyo Co., Ltd., Atsushi Kawakami Speakers bureau: Daiichi Sankyo Co., Ltd., Grant/research support from: Daiichi Sankyo Co., Ltd.

The utility of patent ductus arteriosus closure with hemostatic clip in dogs

This study investigated the utility of patent ductus arteriosus (PDA) closure with hemostatic clip by comparing with traditional PDA closure. Medical records of 51 dogs with surgical closure of PDA were reviewed and retrospective study was conducted. 29 dogs were treated by procedure with hemostatic clip (Group HC), and 22 dogs were treated by surgical ligation (Group SL). Data pertaining to breed, sex, age and body weight at the time of surgery, echocardiographic minimal ductal diameter, duration of surgery, hemostatic clip size, echocardiographic findings, hemor-rhage, residual ductal flow and recanalization were collected from records. The results showed that procedure with hemostatic clip had been selected in lighter dogs than traditional PDA closure. Duration of surgery performed only hemostatic clip technique was significantly shorter than that in group SL. Preoperative LVIDd, E-wave and FS were significantly lower than postoperative ones. As regard all parameters, the differences between pre- and postoperative periods were not significantly different between group HC and group SL. Hemorrhage, residual ductal flow, and recanalization were not significantly different in both groups. The present study showed that procedure with hemostatic clip is beneficial in that it is available in smaller dogs and can make shorter operation duration than traditional PDA closure. Moreover, the procedure is effective for the resolution of volume overload of the left atrium and ventricle in short-term outcome. Complications including hemorrhage, residual ductal flow and recanaliza-tion were not significantly different with both techniques.