Toxic Action Research Articles

Antioxidant and toxicity activities of kayu manis hutan (Cinnamomum iners Reinw. Ex Blume Laureceae) leaf extracts

Cinnamomum iners Reinw. ex Blume Laureceae which is known in Malaysia as “kayu manis” has a wide range of traditional applications for certain plant parts, including the leaves, bark, and stem and it has pharmacological features, including anti-inflammatory and antibacterial activity. Unfortunately, there is a lack of reports regarding the antioxidant and toxicity activities of ethanolic C. iners crude leaf extracts. The objective of the study was to determine the total phenolic content and its antioxidant activities of ethanolic C. iners crude leaf extracts from two different age maturity, as well as its toxicity activity. The extracts were tested for total phenolic content and its antioxidant activities in terms of 2,2-diphenyl-1-picryllhydrazyl (DPPH) free radical scavenging- and ferric reducing antioxidant power (FRAP) and 2,2'-azino-bis(3-ethylbenzothiazoline-6- sulfonic acid) (ABTS) assay. The toxicity assay was tested using brine shrimp (Artemia salina) lethality assay. The total phenolic content of the extracts for young and old leaves C. iners resulted in 248.06±12.77 and 351.11±8.62 mg GAE/g dw, respectively. The DPPH radical scavenging showed results for young and old leaf extracts were IC50 of 31.92 µg/mL and 27.62 µg/mL, respectively. Meanwhile, the value of FRAP for young and old leaf extracts were 8.574±0.21 and 9.155±0.36 TEAC mg/g dw, respectively. The ABTS antioxidant activity for the young and old leaf extracts were 305.23±7.02 and 316.86±8.22 Trolox equivalence mg/g dw, respectively. Based on the toxicity assay, both young and old leaf extracts exhibited LC50 at 19.627 and 13.201 mg/mL, respectively. The findings indicate that C. iners leaves crude extracts have exhibited high total phenolic content and antioxidant activity and the extracts were not toxic against brine shrimp. Thus, C. iners leaf extracts could be developed as potential natural antioxidant agents.

Development and characterization of Artemisia argyi essential oil-loaded nanoemulsion for sustainable weed control: Enhanced stability, amplified activity, protected non-target

Nanotechnology contributes to the development of biopesticides with reduced toxicity, increased stability, improved biosafety, and higher activity against targets. It has demonstrated great potential as a solution for practical applications of essential oils. Herein, the HLB method developed two Artemisia argyi essential oil-loaded nanoemulsions (AEOnano). Further systematically optimizing the ratio led to small droplet size (<200 nm) and low PDI (<0.3). As anticipated, the AEOnano demonstrated robust physical stability when subjected to various stressors. Notably, both indoor and outdoor pot experiments demonstrated that AEOnano outperformed ordinary A. argyi essential oil aqueous emulsions (AEOAE) in weed control. These nanoemulsions allowed a 2–4 times reduction in AEO dosage while maintaining the same weed-killing efficacy. The superior improvement attributed to the nanoemulsions enhanced leaf-wetting capability, improved leaf retention, and resistance to wash-off. In addition, biosafety assessment indicated that AEOnano did not affect the plants (Artemisia argyi, Chrysanthemum morifolium, cotton), which provide orientation for its practical application. Therefore, this study introduces a promising approach to enhance the effectiveness of AEO-based herbicides, which will have a broad application prospect in sustainable agriculture.

Acute Toxicity, Analgesic, and Anti-inflammatory Activities of Folk Thai Herbal Medicine: Yafon Formula

Yafon (YF), a formula composed of 14 herbal constituents, has been used in folk Thai herbal medicine to treat various indications, including pain relief, antipyretics, and anti-inflammatory properties. Nevertheless, this formula lacks adequate toxicological and efficacy data. Hence, this study aims to assess the safety and efficacy of YF in animal models. The study on acute oral toxicity was conducted by the Organization for Economic Co-operation and Development (OECD) number 420 guidelines. The results demonstrated that the administration of YF at a high dose of 2000 mg/kg did not result in fatality or exhibit any toxicity. The analgesic effect of YF in mice was investigated using the acetic acid-induced writhing test and the formalin test. The anti-inflammatory activity of YF was assessed in rats using the carrageenan-induced paw edema test. This investigation employed YF doses of 200, 400, and 800 mg/kg/day. The study found that all YF doses reduced writhing in the acetic acid, and YF doses of 400 and 800 mg/kg/day reduced the licking time in the late phase of the formalin test. In addition, all YF doses effectively suppressed paw edema in the carrageenan-induced paw edema test. This study demonstrated that the YF formula showed no acute toxicity and possessed acute anti-inflammatory and analgesic effects by blocking pain signals originating from the peripheral nervous system. These findings provided empirical evidence supporting the use of YF formula as an analgesic and anti-inflammatory agent.

Abstract PS05-09: A single-arm Phase II clinical study of fulvestrant combined with chemotherapy in the neoadjuvant treatment of HR+/HER2- locally advanced breast cancer

Abstract Background: HR+/HER2- breast cancer has been found to be less sensitive to neoadjuvant chemotherapy (NCT), leading to an objective response rate (ORR) of approximately 65%. Endocrine therapy combined with chemotherapy may help improve the ORR in these patients. The objective of this Phase II study was to evaluate the efficacy and safety of adding fulvestrant to NCT in patients with HR+/HER2- locally advanced breast cancer(LABC). Additionally, the study aimed to investigate the association of 18F-FES PET/CT and metabolites with efficacy. Methods: In this single-arm Phase II study, eligible patients were females with histologically confirmed HR+/HER2- LABC (Stage IIB-IIIC). Patients received fulvestrant (500 mg, on days 0, 14, 28, then every 28 days thereafter, every 4 weeks for six cycles) plus AC-T regimen, followed by surgery. Premenopausal women were administered a concomitant GnRH analogue. Patients underwent 18F-FES PET/CT before the initiation of fulvestrant, and plasma samples were collected for LC-MS analysis at baseline. The primary endpoint was ORR. Secondary endpoints included pathological complete response (tpCR) and safety. Results: From December 2020 to September 2022, 36 patients were enrolled. The median age was 53 years (range35-67). 78% were ECOG PS of 1, 69% were postmenopausal, 92% were nodal involved, and 83% were in stage III. After neoadjuvant therapy, the ORR was 86.1%. All patients completed the surgery, with a tpCR rate of 8.3% (3/36). 80.6% (29/36) patients were classified as Miller-Payne (MP) grade ≥3. Grade ≥3 treatment-emergent adverse events (TEAEs) occurred in 22% (8/36) of the participants. The most common TEAEs were neutropenia (13.9%) and leukopenia (8.3%). The expression of ER, PR, and Ki-67 in postoperative pathology significantly decreased compared to baseline (p &amp;lt; 0.05). Additionally, the change in ER expression was significantly correlated with the regression volume of primary breast tumors (R = 0.56, p = 0.0044). The decrease in ER value in patients with MP ≥ 4 was significantly larger than in patients with MP ≤ 3 (p = 0.0054). Among the 36 patients, 24 completed the 18F-FES PET/CT scan before initiating fulvestrant.The average SUVmax in primary breast lesions was 4.17 (range 1.00-12.80). The SUVmax of breast lesions was significantly correlated with clinical efficacy (p = 0.0018) and with changes in ER expression before and after treatment (R = 0.68, p = 0.00023). Meanwhile, the SUVmax of patients with MP ≥ 4 grade was significantly higher than that of patients with MP ≤ 3 grade (p=0.018). A total of 25 plasma samples were available for metabolic analysis. Among these samples, 13 differential metabolites were identified between patients with MP ≥ 4 grade and MP ≤ 3 grade, which were markedly enriched in 19 metabolic pathways. Conclusions: The addition of fulvestrant to NCT showed manageable toxicity and promising antitumor activity for patients with HR+/HER2- LABC. 18F-FES PET/CT might serve as a tool to predict the effectiveness of neoadjuvant combination therapy. Altered metabolites or metabolic pathways might be associated with the response to this combined treatment approach. Keywords: breast cancer, HR+/HER2-, fulvestrant, neoadjuvant treatment, 18F-FES PET/CT Citation Format: Qing Shao, Jing Wu, Ningning Zhang, Xiaohua Zeng. A single-arm Phase II clinical study of fulvestrant combined with chemotherapy in the neoadjuvant treatment of HR+/HER2- locally advanced breast cancer [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PS05-09.

Abstract PS15-07: Proxalutamide plus Endocrine Therapies in Women with HR+/HER2-/AR+ Metastatic Breast Cancer: A Phase Ic Study

Abstract Abstract Background: Resistance to endocrine therapy (ET) and cyclin-dependent kinase 4/6 inhibitor (CDK4/6i) is a major obstacle to the management of hormone-receptor (HR)+/human epidermal growth factor receptor 2 (HER2)- metastatic breast cancer (mBC). Targeting the AR signaling pathway has been demonstrated with promising results in this population. This phase Ic study aimed to assess the safety, efficacy, pharmacokinetic (PK), and pharmacodynamic (PD) characteristics of the combination of proxalutamide, a high-affinity AR antagonist, with ETs in androgen receptor (AR)+/HR+/HER2- mBC. Methods: Patients in part 1 regimen-finding phase received proxalutamide plus specific ETs (letrozole [cohort A], exemestane [cohort B], or fulvestrant [cohort C]) and were assessed for dose-limiting toxicity (DLT), PK, PD, and anti-tumor activity. Part 2 expansion phase evaluated the safety and efficacy of proxalutamide plus fulvestrant. The primary endpoint was safety and tolerability. Results: Between June 18, 2019, and Sep 15, 2022, 38 (18 in part 1 and 20 in part 2) patients were treated. Efficacy analysis indicated that the ORR was 16.7% (2/12, 95% CI, 2.1%-48.4%) for cohort C and 15.0% (3/20; 95% CI, 3.2%-37.9%) for part 2. Patients achieved a median progression-free survival (PFS) of 6.4 months (95% CI, 2.7-19.3) in cohort C while an mPFS of 11.0 months (95% CI, 5.5- not estimable) in part 2. In part 1, no DLTs were reported. Grade 3 or more treatment-emergent adverse events (TEAEs) were observed in 11 (29.7%) patients (7 [18.9%] in part 1 and 4 [10.8%] in part 2) and mainly included neutrophil count decreased (8.1%) and platelet count decreased (5.4%). Seven (18.9%) had serious AEs (4 [10.8%] in part 1 and 3 [8.1%] in part 2)[1]. PD results showed a greater reduction of estradiol in cohort C compared with that in cohort B. In addition, proxalutamide was absorbed rapidly into the body with the plasma concentrations of proxalutamide and metabolites reaching a nearly steady state on day 29. Patients with AR/ER of ≤1 seemed to achieve longer PFS over those of &amp;gt;1 (8.4 months vs. 4.1 months). Conclusions: These findings suggested favorable clinical outcomes and safety profiles of the combination of proxalutamide and fulvestrant in AR+/HR+/HER2- mBC patients who have progressed on the first-line therapy, and maybe with better efficacy in patients with lower AR/ER ratio. Trial registration: NCT20191063 Citation Format: Hui-Ping Li, Guohong Song, Hanfang Jiang, Xu Liang, Xiaojia Wang, Hua Yang, Lili Zhang, Youzhi Tong. Proxalutamide plus Endocrine Therapies in Women with HR+/HER2-/AR+ Metastatic Breast Cancer: A Phase Ic Study [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PS15-07.

Safety and efficacy of anlotinib combined with taxane and lobaplatin in neoadjuvant treatment of clinical stage II/III triple-negative breast cancer in China (the neoALTAL trial): a single-arm, phase 2 trial

Anlotinib is a new type of tyrosine kinase inhibitor that targets vascular endothelial growth factor receptors 1/2/3, platelet-derived growth factor receptors α/β, and fibroblast growth factor receptors 1-4 and c-Kit, with a broad spectrum of inhibitory effects on tumor angiogenesis and growth. It has been proven effective in HER2-negative metastatic breast cancer, but its efficacy in early-stage triple-negative breast cancer (TNBC) is unknown. This phase 2 study aims to evaluate the efficacy and safety of adding anlotinib to neoadjuvant chemotherapy in patients with TNBC. Patients with clinical stage II/III TNBC were treated with 5 cycles of anlotinib (12mg, d1-14, q3w) plus 6 cycles of taxanes (docetaxel 75 mg/m2 ,d1, q3w or nab-paclitaxel 125 mg/m2, d1 and d8, q3w) and lobaplatin (30 mg/m2, d1, q3w), followed by surgery. The primary endpoint was pathological complete response (pCR; ypT0/is ypN0) and the secondary endpoints include breast pCR (bpCR), axillary pCR (apCR), residual cancer burden (RCB), objective response rate (ORR), survival, and safety. Exploratory endpoints were efficacy biomarkers based on Fudan University Shanghai Cancer Center Immunohistochemical (FUSCC IHC) classification for TNBC and next-generation sequencing (NGS) of DNA from tumor tissue and blood samples of patients with 425-gene panel. This trial is registered with www.chictr.org.cn (ChiCTR2100043027). From Jan 2021 to Aug 2022, 48patients were assessed and 45 were enrolled. All patients received at least one dose of study treatment and underwent surgery. The median age was 48.5 years (SD: 8.7), 71% were nodal involved, and 20% had stage III. In the intention-to-treat population, 26 out of 45patients achieved pCR (57.8%; 90% CI, 44.5%-70.3%), and 39 achieved residual cancer burden class 0-I (86.7%; 95% CI, 73.2%-94.9%). The bpCR and apCR rate were 64.4% (29/45) and 71.9% (23/32), respectively. No recurrence or metastasis occurred during the short-term follow-up. Based on the FUSCC IHC-based subtypes, the pCR rates were 68.8% (11/16) for immunomodulatory subtype, 58.3% (7/12) for basal-like immune-suppressed subtype and 33.3% (4/12) for luminal androgen receptor subtype, respectively. NGS revealed that the pCR were 77% (10/13) and 50% (14/28) in MYC-amplified and wild-type patients, respectively, and 78% (7/9) and 53% (17/32) in gBRCA1/2-mutated and wild-type patients, respectively. The median follow-up time of the study was 14.9 months (95% CI: 13.5-16.3 months). There was no disease progression or death during neoadjuvant therapy. No deaths occurred during postoperative follow-up. In the safety population (N=45), Grade 3 or 4 treatment emergent adverse events occurred in 29patients (64%), and the most common events were neutropenia (38%), leukopenia (27%), thrombocytopenia (25%), anemia (13%), and hypertension (13%), respectively. The addition of anlotinib to neoadjuvant chemotherapy showed manageable toxicity and encouraging antitumor activity for patients with clinical stage II/III TNBC. Chongqing Talents Project, Chongqing Key Project of Technology Innovation and Application Development and Chongqing Outstanding Youth Natural Science Foundation.

Biomass waste derived from cassia fistula into value-added porous carbon electrode for aqueous symmetric supercapacitors

Activated carbon derived from biomass sources has been renowned as one of the key materials and economical precursors for numerous energy conversion and storage applications. Herein, we utilized a less explored Cassia fistula (Pulp and seed) biomass as the carbon source for supercapacitor application. Further, a less toxic and low activation method has been implemented to activate the biomass-derived carbon. The highly dense seed resulted in better porous compared to the pulp source. The electrochemical performances of the bio-carbon electrodes have been examined by CV, GCD, and EIS studies. The activated carbon derived from the Cassia fistula seed (CFSA) electrode achieved a specific capacitance value of 136.5 Fg−1 at 0.5 Ag−1 in 3 M KOH. Moreover, the electrode demonstrates an extremely long stability by sustaining 98 % of initial capacitance after 10,000 cycles, which signifies the robust electrochemical stability behavior of the obtained electrode. Further, the aqueous symmetric supercapacitor achieved a maximum energy and power density of 7.2 WhKg−1 and 3488.1 WKg−1, respectively. Likewise, after 10,000 stability cycles, the cell retains 96.4 % capacitance at 5 Ag−1 which denotes the noteworthy capacitive behaviour of the CFSA electrode. Thus, the present work suggests an eco-friendly resource for developing an effectual carbon electrode for energy storage applications.

In Vitro and In Silico Biological Evaluation of the Essential Oil from Syzigium cumini Leaves as a Source of Novel Antifungal and Trichomonacidal Agents

As microbes develop resistance to various drugs, the treatment of infections becomes increasingly challenging, leading to prolonged illness, heightened severity of infections, elevated mortality rates, and increased healthcare costs. Essential oils are lipophilic and volatile mixtures of compounds that have gained attention in research for novel antimicrobial agents. Therefore, the present study evaluated the essential oil of Syzygium cumini leaves (EOSC) in order to prospect its antifungal and trichomonacidal activities. The essential oil from the leaves was extracted by steam distillation and analyzed by GC-MS. Antifungal activity was evaluated using the serial microdilution method. Additionally, the potential of the EOSC as an enhancer of fluconazole (FCZ) action was tested at subinhibitory concentrations. To assess anti-Trichomonas vaginalis activity, concentrations ranging from 15.6 to 500 μg/mL of EOSC were tested. Finally, the SwissADME platform was employed to analyze the physicochemical and pharmacokinetic characteristics of the major component of EOSC. The GC-MS analysis identified 94.24% of the components of EOSC, with α-pinene (51.11%) and nerol (8.25%) as major constituents. EOSC exhibited low antifungal activity against the evaluated Candida strains. However, the combination of EOSC and FCZ reduced the IC50 against Candida krusei from 45.29 to 0.30 μg/mL. EOSC also demonstrated significant activity against T. vaginalis (IC50 = 88.2 μg/mL). In silico prediction with α-pinene showed low toxic action and important physicochemical aspects for drug production. The essential oil of Syzygium cumini emerges as a promising candidate for the discovery of molecules with potential antifungal and anti-Trichomonas vaginalis applications.

Acute toxicity of binary mixtures for quorum sensing inhibitors and sulfonamides against Aliivibrio fischeri: QSAR investigations and joint toxic actions

Quorum sensing inhibitors (QSIs), as a kind of ideal antibiotic substitutes, have been recommended to be used in combination with traditional antibiotics in medical and aquaculture fields. Due to the co-existence of QSIs and antibiotics in environmental media, it is necessary to evaluate their joint risk. However, there is little information about the acute toxicity of mixtures for QSIs and antibiotics. In this study, 10 QSIs and 3 sulfonamides (SAs, as the representatives for traditional antibiotics) were selected as the test chemicals, and their acute toxic effects were determined using the bioluminescence of Aliivibrio fischeri (A. fischeri) as the endpoint. The results indicated that SAs and QSIs all induced S-shaped dose-responses in A. fischeri bioluminescence. Furthermore, SAs possessed greater acute toxicity than QSIs, and luciferase (Luc) might be the target protein of test chemicals. Based on the median effective concentration (EC50) for each test chemical, QSI-SA mixtures were designed according to equitoxic (EC50(QSI):EC50(SA) = 1:1) and non-equitoxic ratios (EC50(QSI):EC50(SA) = 1:10, 1:5, 1:0.2, and 1:0.1). It could be observed that with the increase of QSI proportion, the acute toxicity of QSI-SA mixtures enhanced while the corresponding TU values decreased. Furthermore, QSIs contributed more to the acute toxicity of test binary mixtures. The joint toxic actions of QSIs and SAs were synergism for 23 mixtures, antagonism for 12 mixtures, and addition for 1 mixture. Quantitative structure–activity relationship (QSAR) models for the acute toxicity QSIs, SAs, and their binary mixtures were then constructed based on the lowest CDOCKER interaction energy (Ebind-Luc) between Luc and each chemical and the component proportion in the mixture. These models exhibited good robustness and predictive ability in evaluating the toxicity data and joint toxic actions of QSIs and SAs. This study provides reference data and applicable QSAR models for the environmental risk assessment of QSIs, and gives a new perspective for exploring the joint effects of QSI-antibiotic mixtures

Comparison of the Toxicity of Watermelon Rind Extract (Citrullus lanatus) and Melon Rind Extract Using BSLT Method

Toxicity analysis is a preliminary test to observe a toxic pharmacological activity to find a safe dose to be developed into a new drug. The plants that potentially have poisonous effects are Watermelon rind (Citrullus lanatus) and Melon rind (Cucumis melo). The purpose of this study was determine the toxic potential of watermelon rind and melon rind using Brine Shrimp Lethality Test. Test BSLT and phytochemical screening. The results of research on watermelon rind and melon rind contain secondary metabolites, amely alkaloids, flavonoids, tannins, saponins. The result of the BSLT test watermelon rind extract and melon rind extract were different. For watermelon rind extract, the LC50 value was 305,19 µg/ml and for melon rind extract, the LC50 value was 816,73 µg/ml. The LC50 value pbtained from the research results of the two samplees is toxic to Artemia salina Leach, because the LC50 value is &lt; 1000 µg/ml. Statistical test results using One Way Anova obtained a significant value of 0.027 where there were significant differences in the two samplesand various concertration, but both plants had the same toxic effect on Artemia salina Leach larvae. Keywords: Citrullus lanatus; Cucumis melo; LC50; toxicity

Assessing the impact of two conventional wastewater treatment plants on small streams with effect-based methods

Sixty percent of discrete surface water bodies in Europe do not meet the requirements for good ecological and chemical status and in Germany, the situation is even worse with over 90% of surface water bodies failing to meet the threshold. In addition to hydromorphological degradation, intensive land use and invasive species, chemical pollution is primarily considered to be responsible for the inadequate ecological status of the water bodies. As a quantitatively important source of micropollutants, wastewater treatment plants (WWTPs) represent an important entry path for chemical stressors. It is therefore important to analyze the effectiveness of the WWTPs in eliminating micropollutants and other chemical stressors to mitigate the negative impacts of the treated wastewater (WW) in aquatic ecosystems. Accordingly, in this study, we evaluated the impacts of two conventional, medium-sized WWTPs on their small receiving water systems in the southwestern region of Hessen in Germany during two sampling campaigns (spring and fall) using effect-based methods (EBM). We hypothesized that due to the insufficient elimination of micropollutants, a broad spectrum of toxic effects would be detected in conventionally treated WW and also in the receiving surface waters downstream the WWTPs. As EBMs a battery of in vitro assays and active biomonitoring using two in vivo assays were applied. The results supported our hypothesis and showed that the untreated WW had a very high baseline toxicity and also high endocrine and mutagenic activities. Conventional WW treatment, consisting of mechanical and biological treatment with nitrification, denitrification and phosphate precipitation, reduced baseline toxicity by more than 90% and endocrine activities by more than 80% in both WWTPs. Despite these high elimination rates, the remaining baseline toxicity, the endocrine, dioxin-like and mutagenic activities of the conventionally treated WW were so high that negative effects on the two receiving waters were to be expected. This was confirmed in the active monitoring with the amphipod Gammarus fossarum and the mudsnail Potamopyrgus antipodarum, as mortality of both species increased downstream of the WWTPs and reproduction in P. antipodarum was also affected. These results indicate that advanced WW treatment is needed to more effectively eliminate chemical stressors to prevent negative impacts of treated WW particularly in small receiving waters.

Elicitors of plant defenses as a standalone tactic failed to provide sufficient protection to fruits against spotted-wing drosophila

Spotted-wing drosophila, Drosophila suzukii (Matsumura), is a globally important invasive pest of soft-skinned fruits including raspberries, blueberries, and strawberries. Current control measures for this pest primarily rely on calendar-based insecticide sprays; therefore, more sustainable methods are desirable. Adults of D. suzukii use cues derived from fruits and symbiotic microbes to identify optimal sites for feeding, mating, and oviposition. We hypothesized that modifying any of these cues could influence D. suzukii adult behavior, making them less likely to select suitable fruits. One approach involves applying synthetic elicitors of the salicylic acid (SA) and jasmonic acid (JA) plant defense pathways, which are associated with defenses against pathogens and herbivores, respectively, or the use of crop sterilants, employed for microbial control, to reduce D. suzukii attraction, oviposition, and larval performance in fruits. Here, the preference and performance of D. suzukii was investigated in blueberry fruits treated exogenously with four commercial elicitors of plant defenses – three that primarily activate SA-related defenses (Actigard, LifeGard, and Regalia) and one activator of JA-related defenses (Blush) – and the crop sterilant OxiDate. A series of choice and no-choice experiments were conducted in laboratory, semi-field, and field settings that were performed at various time intervals to assess the residual effects of each treatment. Our results showed no consistent repellent, oviposition deterrent, or larval toxicity activity for any of the products tested. As a result, our findings do not provide sufficient support to recommend the use of these elicitors or the crop sterilant as viable standalone options for D. suzukii management.

Varlitinib and Paclitaxel for EGFR/HER2 Co-Expressing Advanced Gastric Cancer: a Multicenter Phase Ib/II Study (K-MASTER-13).

Varlitinib is a pan-human epidermal growth (HER) inhibitor targeting epidermal growth factor receptor (EGFR), HER2, and HER4. We present a phase Ib/II study of a combination of varlitinib and weekly paclitaxel as a second-line treatment for patients with EGFR/HER2 co-expressing advanced gastric cancer (AGC). Patients whose tumors with EGFR and HER2 overexpression by immunohistochemistry (IHC) (≥1+) were enrolled. Varlitinib and paclitaxel were investigated every 4 weeks. After determining the recommended phase II dose (RP2D) in phase Ib, a phase II study was conducted to evaluate the antitumor activity. RP2D was treated with a combination of varlitinib (300 mg twice daily) and paclitaxel. Among 27 patients treated with RP2D, the median PFS and overall survival (OS) were 3.3 months and 7.9 months, respectively, with a median follow-up of 15.7 months. Among 16 patients with measurable disease, the objective response rate (ORR) and disease control rate were 31% and 88%, respectively. Patients with strong HER2 expression (n=8) had a higher ORR and longer OS, whereas those with strong EGFR expression (n=3) had poorer outcomes. The most common adverse events (AEs) of any grade were neutropenia (52%), diarrhea (27%), AST/ALT elevation (22%), and nausea (19%). No treatment-related deaths or unexpected AEs resulting from treatment cessation were observed in patients with RP2D. A combination of varlitinib and paclitaxel displayed manageable toxicity and modest antitumor activity in patients with EGFR/HER2 co-expressing AGC who progressed after first-line chemotherapy.

Decoding the Structure-Function Relationship of the Muramidase Domain in E. coli O157.H7 Bacteriophage Endolysin: A Potential Building Block for Chimeric Enzybiotics.

Bacteriophage endolysins are potential alternatives to conventional antibiotics for treating multidrug-resistant gram-negative bacterial infections. However, their structure-function relationships are poorly understood, hindering their optimization and application. In this study, we focused on the individual functionality of the C-terminal muramidase domain of Gp127, a modular endolysin from E. coli O157:H7 bacteriophage PhaxI. This domain is responsible for the enzymatic activity, whereas the N-terminal domain binds to the bacterial cell wall. Through protein modeling, docking experiments, and molecular dynamics simulations, we investigated the activity, stability, and interactions of the isolated C-terminal domain with its ligand. We also assessed its expression, solubility, toxicity, and lytic activity using the experimental data. Our results revealed that the C-terminal domain exhibits high activity and toxicity when tested individually, and its expression is regulated in different hosts to prevent self-destruction. Furthermore, we validated the muralytic activity of the purified refolded protein by zymography and standardized assays. These findings challenge the need for the N-terminal binding domain to arrange the active site and adjust the gap between crucial residues for peptidoglycan cleavage. Our study shed light on the three-dimensional structure and functionality of muramidase endolysins, thereby enriching the existing knowledge pool and laying a foundation for accurate in silico modeling and the informed design of next-generation enzybiotic treatments.

Combination of Chemical and Physical Cancer Therapeutics Developed with Microcapsules Made of κ-Casein and Gold Nanoparticles in the Presence of Drug-Loaded Phase Change Materials.

Tumor heterogeneity requires development of an anticancer system equipped with both chemical and physical therapeutics to eradicate cancer exhibiting drug resistance and clonal evolution into diverse tumor cells. Assortment of various toxic components into one platform without compromising their individual toxic activity remains a formidable task. Herein, a novel drug delivery system (DDS) exerting potent cytotoxicity toward cancer cells was fabricated with gold nanoparticles (AuNPs) coated with an innocuous self-assembly protein of κ-casein (κC). Pickering emulsions of the κC-AuNP conjugates in the presence of chloroform inside led to the κC-AuNP microcapsules being stabilized via robust β-sheet formation between κC molecules located on the single-layered shell made of κC-AuNPs. Phase change material (PCM) comprising a eutectic mixture of lauric acid and myristic acid with the melting point of 43 °C was encapsulated in the presence of a hydrophilic anticancer drug of doxorubicin (Dox), in which the PCM has played multiple functions such as drug-holding matrix and thermoresponsive gating material for drug release. Once liberated with the heat generated by the AuNPs upon a near-infrared (NIR) irradiation at 808 nm, the PCM by itself exhibited not only chemical cytotoxicity but also physical toxic effects such as membrane destabilization of the cells and a possible cellular fixative effect toward cancer cells by the solidified PCM at body temperature. Moreover, the PCM was shown to facilitate the intranuclear localization of Dox. As a result, the DDS comprising κC-AuNP microcapsules containing Dox-loaded PCM was demonstrated to show a powerful anticancer effect upon the NIR irradiation, which unleashed several toxic agents such as Dox, PCM, heat-generating AuNPs, and tissue-immobilizing solidified PCM. Therefore, the κC-AuNP microcapsules would serve as an anticancer system into which diverse chemical and physical therapeutic agents could be combined to effectively remove the heterogeneous and drug resistant cancer cells.

Identification of type VI secretion system effector-immunity pairs using structural bioinformatics.

The type VI secretion system (T6SS) is an important mediator of microbe-microbe and microbe-host interactions. Gram-negative bacteria use the T6SS to inject T6SS effectors (T6Es), which are usually proteins with toxic activity, into neighboring cells. Antibacterial effectors have cognate immunity proteins that neutralize self-intoxication. Here, we applied novel structural bioinformatic tools to perform systematic discovery and functional annotation of T6Es and their cognate immunity proteins from a dataset of 17,920 T6SS-encoding bacterial genomes. Using structural clustering, we identified 517 putative T6E families, outperforming sequence-based clustering. We developed a logistic regression model to reliably quantify protein-protein interaction of new T6E-immunity pairs, yielding candidate immunity proteins for 231 out of the 517 T6E families. We used sensitive structure-based annotation which yielded functional annotations for 51% of the T6E families, again outperforming sequence-based annotation. Next, we validated four novel T6E-immunity pairs using basic experiments in E. coli. In particular, we showed that the Pfam domain DUF3289 is a homolog of Colicin M and that DUF943 acts as its cognate immunity protein. Furthermore, we discovered a novel T6E that is a structural homolog of SleB, a lytic transglycosylase, and identified a specific glutamate that acts as its putative catalytic residue. Overall, this study applies novel structural bioinformatic tools to T6E-immunity pair discovery, and provides an extensive database of annotated T6E-immunity pairs.

Exploration of beauvericin's toxic effects and mechanisms in human astrocytes and N-acetylcysteine's protective role

Beauvericin (BEA) is a newly identified mycotoxin produced by various Fusarium species, and its contamination in food and animal feed is widespread globally. This mycotoxin demonstrates cytotoxic effects by inducing oxidative stress in multiple models. Furthermore, evidence indicates that BEA possesses diverse toxic activities, making it a promising candidate for toxicological research. Recent studies have highlighted the ability of BEA to traverse the blood-brain barrier, suggesting its potential neurotoxicity. However, limited information is available regarding the neurotoxic effects of BEA on human astrocytes. Therefore, this study aimed to assess the neurotoxic effects of BEA on the Gibco® Human Astrocyte (GHA) cell line and elucidate the underlying mechanisms. Additionally, the study aimed to investigate the protective effects of the antioxidant N-acetylcysteine (NAC) against BEA-induced toxicity. The data show that exposure to BEA within the 2.5–15 μM concentration range resulted in concentration-dependent cytotoxicity. BEA-treated cells exhibited significantly increased levels of reactive oxygen species (ROS), while intracellular glutathione (GSH) content was significantly reduced. Western blot analysis of cells treated with BEA revealed altered protein levels of Bax, cleaved caspase-9, and caspase-3, along with an increased Bax/Bcl-2 ratio, indicating the induction of apoptosis. Additionally, BEA exposure triggered antioxidant responses, as evidenced by increased protein expression of Nrf2, HO-1, and NQO1. Significantly, pretreatment with NAC partially attenuated the significant toxic effects of BEA. In conclusion, our findings suggest that BEA-induced cytotoxicity in GHA cells involves oxidative stress-associated apoptosis. Furthermore, NAC demonstrates potential as a protective agent against BEA-induced oxidative damage.

Evidence that Alzheimer's Disease Is a Disease of Competitive Synaptic Plasticity Gone Awry.

Mounting evidence indicates that a physiological function of amyloid-β (Aβ) is to mediate neural activity-dependent homeostatic and competitive synaptic plasticity in the brain. I have previously summarized the lines of evidence supporting this hypothesis and highlighted the similarities between Aβ and anti-microbial peptides in mediating cell/synapse competition. In cell competition, anti-microbial peptides deploy a multitude of mechanisms to ensure both self-protection and competitor elimination. Here I review recent studies showing that similar mechanisms are at play in Aβ-mediated synapse competition and perturbations in these mechanisms underpin Alzheimer's disease (AD). Specifically, I discuss evidence that Aβ and ApoE, two crucial players in AD, co-operate in the regulation of synapse competition. Glial ApoE promotes self-protection by increasing the production of trophic monomeric Aβ and inhibiting its assembly into toxic oligomers. Conversely, Aβ oligomers, once assembled, promote the elimination of competitor synapses via direct toxic activity and amplification of "eat-me" signals promoting the elimination of weak synapses. I further summarize evidence that neuronal ApoE may be part of a gene regulatory network that normally promotes competitive plasticity, explaining the selective vulnerability of ApoE expressing neurons in AD brains. Lastly, I discuss evidence that sleep may be key to Aβ-orchestrated plasticity, in which sleep is not only induced by Aβ but is also required for Aβ-mediated plasticity, underlining the link between sleep and AD. Together, these results strongly argue that AD is a disease of competitive synaptic plasticity gone awry, a novel perspective that may promote AD research.

Unlocking the genome of the non-sourdough Kazachstania humilis MAW1: insights into inhibitory factors and phenotypic properties

BackgroundAscomycetous budding yeasts are ubiquitous environmental microorganisms important in food production and medicine. Due to recent intensive genomic research, the taxonomy of yeast is becoming more organized based on the identification of monophyletic taxa. This includes genera important to humans, such as Kazachstania. Until now, Kazachstania humilis (previously Candida humilis) was regarded as a sourdough-specific yeast. In addition, any antibacterial activity has not been associated with this species.ResultsPreviously, we isolated a yeast strain that impaired bio-hydrogen production in a dark fermentation bioreactor and inhibited the growth of Gram-positive and Gram-negative bacteria. Here, using next generation sequencing technologies, we sequenced the genome of this strain named K. humilis MAW1. This is the first genome of a K. humilis isolate not originating from a fermented food. We used novel phylogenetic approach employing the 18 S-ITS-D1-D2 region to show the placement of the K. humilis MAW1 among other members of the Kazachstania genus. This strain was examined by global phenotypic profiling, including carbon sources utilized and the influence of stress conditions on growth. Using the well-recognized bacterial model Escherichia coli AB1157, we show that K. humilis MAW1 cultivated in an acidic medium inhibits bacterial growth by the disturbance of cell division, manifested by filament formation. To gain a greater understanding of the inhibitory effect of K. humilis MAW1, we selected 23 yeast proteins with recognized toxic activity against bacteria and used them for Blast searches of the K. humilis MAW1 genome assembly. The resulting panel of genes present in the K. humilis MAW1 genome included those encoding the 1,3-β-glucan glycosidase and the 1,3-β-glucan synthesis inhibitor that might disturb the bacterial cell envelope structures.ConclusionsWe characterized a non-sourdough-derived strain of K. humilis, including its genome sequence and physiological aspects. The MAW1, together with other K. humilis strains, shows the new organization of the mating-type locus. The revealed here pH-dependent ability to inhibit bacterial growth has not been previously recognized in this species. Our study contributes to the building of genome sequence-based classification systems; better understanding of K.humilis as a cell factory in fermentation processes and exploring bacteria-yeast interactions in microbial communities.

Enhance the physicochemical properties of the citronella oil -SLNPs to improve the insecticidal activity against Spodoptera littoralis (Boisd) (Lep. Nactuidae)

The Nano-formulation of citronella essential oil (Cymbopogon nardus (L.) and their mixtures of three adjuvants (Provecta®, Top film®, and PEG600-dioleate) were studied to enhance physico-chemical properties of the Nano-formulation and improve the insecticidal effect against Spodoptera littoralis (Boisd). Characterisation of physicochemical properties of Nano-formulation was studied by calculating droplet size, polydispersity index (PDI), and Zeta-potential parameters. The results showed that the Solid Lipid Nanoparticles (SLNs) mixtures of three adjuvant mixtures had more toxic activity and stability than the Nano-formulation alone. Before storage the acidity, alkalinity (pH), and viscosity exhibited an acidic pH value in the range (4.11–5.34), whereas after three months of storage was recorded high pH, a shift in the pH on storage can indicate the instability of active substances or product under semi field-laboratory conditions. Nano-formulation of the citronella oil mixed with the three adjuvants increased the mortality percentage of S. littoralis larvae.