Beneath the surface: Exploring microplastic intricacies in Anadara granosa.

Anadara granosa or blood cockles have been reported to be a candidate for biomonitoring agents due to their sedimentary nature and their nutrient uptake mechanisms. Yet, this bivalve is still regarded as a delicacy in Asian cuisine. Malaysia is the largest exporter of this sea product that contaminated cockles may also be experienced by the importing countries. However, the bioaccumulation of microplastics in A. granosa cultivated in Malaysia has not been extensively studied. It is crucial to comprehend the risk posed to humans by consuming A. granosa in their diet. Therefore, the purpose of this research is to investigate the levels of microplastic accumulation in A. granosa from major exporters in Peninsular Malaysia, to evaluate the associated risk of microplastics on the species, and to estimate daily human consumption of microplastics through the consumption of A. granosa. The abundance of microplastics was quantified through the use of a stereo microscope, and the polymer type was determined using FTIR and micro-FTIR. Findings from this investigation revealed that all samples of A. granosa were contaminated with microplastics, with the highest levels of accumulation found in bivalves collected from the west coast (0.26 ± 0.15 particles/g) of Peninsular Malaysia. Fragment and fiber microplastics, measuring between 0.05 and 0.1 mm in size, were found to be the most prevalent in A. granosa, with blue being the dominant identified colour and rayon being the most common polymer type. Microplastic risk assessment due to the presence of polyacrylate, polycarbonate (PC), and polymethyl methacrylate (PMMA) resulted in a high risk of contamination for A. granosa. It was further determined that the current estimated dietary intake (EDI) suggests that consumers of A. granosa uptake approximately 21.8-93.5 particles/person/year of microplastics. This study highlights that A. granosa accumulates microplastics, which could potentially result in bioaccumulation and biomagnification in humans through consumption.

What samples are suitable for monitoring antimicrobial-resistant genes? Using NGS technology, a comparison between eDNA and mrDNA analysis from environmental water.

Introduction: The rise in antimicrobial resistance (AMR) that is affecting humans, animals, and the environment, compromises the human immune system and represents a significant threat to public health. Regarding the impact on water sanitation, the risk that antimicrobial-resistant genes (ARGs) and antimicrobial-resistant bacteria in surface water in cities pose to human health remains unclear. To determine the prevalence of AMR in environmental surface water in Japan, we used DNA sequencing techniques on environmental water DNA (eDNA) and the DNA of multidrug-resistant bacteria (mrDNA). Methods: The eDNA was extracted from four surface water samples obtained from the Tokyo area and subjected to high- throughput next-generation DNA sequencing using Illumina-derived shotgun metagenome analysis. The sequence data were analyzed using the AmrPlusPlus pipeline and the MEGARes database. Multidrug-resistant bacteria were isolated using a culture-based method from water samples and were screened by antimicrobial susceptibility testing (for tetracycline, ampicillin-sulbactam, amikacin, levofloxacin, imipenem, and clarithromycin). Of the 284 isolates, 22 were identified as multidrug-resistant bacteria. The mrDNA was sequenced using the Oxford nanopore MinION system and analyzed by NanoARG, a web service for detecting and contextualizing ARGs. Results and discussion: The results from eDNA and mrDNA revealed that ARGs encoding beta-lactams and multidrug resistance, including multidrug efflux pump genes, were frequently detected in surface water samples. However, mrDNA also revealed many sequence reads from multidrug-resistant bacteria, as well as nonspecific ARGs, whereas eDNA revealed specific ARGs such as pathogenic OXA-type and New Delhi metallo (NDM)-beta-lactamase ARGs. Conclusion: To estimate potential AMR pollution, our findings suggested that eDNA is preferable for detecting pathogen ARGs.

Pharmacokinetic Properties of Single and Repeated Injection of Liposomal Platelet Substitute in a Rat Model of Red Blood Cell Transfusion-Induced Dilutional Thrombocytopenia.

A preclinical study of dodecapeptide ((400)HHLGGAKQAGDV(411)) (H12)-(adenosine diphosphate, ADP)-liposomes for use as a synthetic platelet (PLT) substitute under conditions of red blood cell (RBC) transfusion-induced dilutional thrombocytopenia is limited to pharmacological effect. In this study, the pharmacokinetics of H12-(ADP)-liposomes in RBC transfusion-induced dilutional thrombocytopenic rats were evaluated. As evidenced by the use of (14) C, (3) H double-radiolabeled H12-(ADP)-liposomes in which the encapsulated ADP and liposomal membrane were labeled with (14) C and (3) H, respectively, the H12-(ADP)-liposomes remained intact in the blood circulation for up to 3 h after injection, and were mainly distributed to the liver and spleen. The encapsulated ADP was mainly eliminated in the urine, whereas the outer membrane was mainly eliminated in the feces. These successive pharmacokinetic properties of the H12-(ADP)-liposomes in RBC transfusion-induced dilutional thrombocytopenic rats were similar to those in healthy rats, except for the shorter retention time in the circulation. When H12-(ADP)-liposomes were repeatedly injected into RBC transfusion-induced dilutional thrombocytopenic rats at intervals of 5 days at a dose of 10 mg lipids/kg, the second dose of injected H12-(ADP)-liposomes were rapidly cleared from the circulation, namely, via the accelerated blood clearance phenomenon. These novel pharmacokinetic findings provide useful information for the further development of H12-(ADP)-liposomes as a PLT substitute.

Resveratrol increases CD68⁺ Kupffer cells colocalized with adipose differentiation-related protein and ameliorates high-fat-diet-induced fatty liver in mice.

SCOPE: Resveratrol reportedly improves fatty liver. This study purposed to elucidate the effect of resveratrol on fatty liver in mice fed a high-fat (HF) diet, and to investigate the role of liver macrophages (Kupffer cells). METHODS AND RESULTS: C57BL/6 mice were divided into three groups, receiving either a control diet, HF diet (50% fat), or HF supplemented with 0.2% resveratrol (HF + res) diet, for 8 weeks. Compared with the HF group, the HF + res group exhibited markedly attenuated fatty liver, and reduced lipid droplets (LDs) in hepatocytes. Proteomic analysis demonstrated that the most downregulated protein in the livers of the HF + res group was adipose differentiation-related protein (ADFP), which is a major constituent of LDs and reflects lipid accumulation in cells. The HF + res group exhibited greatly increased numbers of CD68(+) Kupffer cells with phagocytic activity. Immunohistochemistry showed that several CD68(+) Kupffer cells were colocalized with ADFP immunoreaction in the HF + res group. Additionally, the HF + res group demonstrated markedly decreased TNF-alpha production, which confirmed by both liver mononuclear cells stimulated by LPS in vitro and in situ hybridization analysis, compared with the HF group. CONCLUSION: Resveratrol ameliorated fatty liver and increased CD68-positive Kupffer cells with downregulating ADFP expression.

Mep72, a metzincin protease that is preferentially secreted by biofilms of Pseudomonas aeruginosa.

In this work, we compared the profile of proteins secreted by planktonic and biofilm cultures of Pseudomonas aeruginosa using two-dimensional difference gel electrophoresis (2D-DiGE). This revealed that a novel metzincin protease, Mep72, was secreted during biofilm growth. Subsequent Western blotting and reverse transcription-PCR (RT-PCR) analyses demonstrated that Mep72 was expressed only during biofilm growth. Mep72 has a tridomain structure comprised of a metzincin protease-like domain and two tandem carbohydrate-binding domains. Unlike the only other metzincin (alkaline protease; AprA) in P. aeruginosa, Mep72 is secreted through the type II pathway and undergoes processing during export. During this processing, the metzincin domain is liberated from the carbohydrate-binding domains. This processing may be self-catalyzed, since purified Mep72 autodegraded in vitro. This autodegradation was retarded in the presence of alginate (an extracellular matrix component of many P. aeruginosa biofilms). The expression of full-length mep72 in Escherichia coli was toxic. However, this toxicity could be alleviated by coexpression of mep72 with the adjacent gene, bamI. Mep72 and BamI were found to form a protein-protein complex in vitro. 2D-DiGE revealed that the electrophoretic mobility of several discrete protein spots was altered in the biofilm secretome of an mep72 mutant, including type III secretion proteins (PopD, PcrV, and ExoS) and a flagellum-associated protein (FliD). Mep72 was found to bind directly to ExoS and PcrV and to affect the processing of these proteins in the biofilm secretome. We conclude that Mep72 is a secreted biofilm-specific regulator that affects the processing of a very specific subset of virulence factors.

Treatment with fibrinogen γ-chain peptide-coated, adenosine 5'-diphosphate-encapsulated liposomes as an infusible hemostatic agent against active liver bleeding in rabbits with acute thrombocytopenia.

BACKGROUND: We evaluated the hemostatic efficacy of H12-(adenosine 5'-diphosphate [ADP])-liposomes in the setting of active liver bleeding in rabbits with dilutional thrombocytopenia after massive transfusion. STUDY DESIGN AND METHODS: Acute thrombocytopenia (platelet [PLT] count < 50 × 10(9) /L) was induced in rabbits by repeated blood withdrawal and isovolemic transfusion of autologous washed red blood cells. Liver hemorrhage was initiated by a penetrating liver injury. Subsequently, the animals received tamponade treatment for the liver hemorrhage for 5 minutes and were intravenously administered H12-(ADP)-liposomes with PLT-poor plasma (PPP), PLT-rich plasma (PRP), PPP alone, H12-(phosphate-buffered saline [PBS])-liposome/PPP, or H12-(ADP)-liposomes/PPP plus fibrinogen concentrate during the tamponade. RESULTS: Administration of H12-(ADP)-liposomes/PPP rescued 60% of the rabbits from the liver hemorrhage; PRP administration rescued 50%. In contrast, rabbits receiving PPP or H12-(PBS)-liposome/PPP achieved only 10 or 17% survival, respectively, for the first 24 hours. H12-(ADP)-liposomes/PPP as well as PRP consistently reduced bleeding volumes and shortened clotting times (CTs) in comparison to PPP administration. Specifically, bleeding volumes in the initial 5 minutes averaged 11 mL (H12-(ADP)-liposomes/PPP) and 17 mL (PRP) versus 30 mL (PPP; p < 0.05); CTs averaged 270 and 306 seconds versus 401 seconds (p < 0.05). H12-(ADP)-liposomes were observed at the bleeding site with thrombus formation, suggesting an induction of thrombi. Neither macro- nor microthrombi were detected in the lung, kidney, spleen, or liver in rabbits treated with H12-(ADP)-liposomes. Supplementation of fibrinogen to H12-(ADP)-liposomes/PPP did not significantly improve rabbit survival. CONCLUSIONS: H12-(ADP)-liposomes might be a safe and effective therapeutic tool during damage control surgery for trauma patients with acute thrombocytopenia and massive bleeding.

Detection of changes in the structure and distribution map of triacylglycerol in fatty liver model by MALDI-SpiralTOF.

Matrix-assisted laser desorption/ionisation spiral orbit-type time-of-flight mass spectrometry (MALDI-SpiralTOF) can analyse lipid profiles and characterise lipid structure. Imaging mass spectrometry (IMS) also provides distribution maps of selected m/z values. Here, we investigated triacylglycerol (TG) structure and distribution using these technologies to estimate mouse fatty liver. The distribution and intensity of the most intense mass spectrum ion was indicated by IMS at m/z 881.7 (52:2). Analysis using MS/MS showed a structural change between liver TG and dietary TG. These findings suggest that MALDI-SpiralTOF is a powerful tool for clinical screening and estimating fatty liver.

Stathmin is involved in the cooperative effect of Zoledronic acid and gefitinib on bone homing breast cancer cells in vitro.

Zoledronic acid (Zol) is the most potent inhibitor of bone resorption among the bisphosphonates and is commonly used for inhibiting bone metastasis. However, it remains unclear whether Zol provides a survival benefit. Recent findings indicate that epidermal growth factor (EGF) signaling is an important mediator of bone metastasis. Thus, we examined the combined effects of Zol and an EGF receptor-tyrosine kinase inhibitor, gefitinib, on the proliferation and invasion of a bone-seeking clone and the breast cancer cell line MDA-MB-231. Combined treatment with Zol and gefitinib synergistically inhibited both invasion and cell proliferation of the bone-seeking clone, but not those of the MDA-MB-231 cells. Two-dimensional difference gel electrophoresis and mass spectrometry demonstrated that stathmin was down-regulated during these cooperative effects. Stathmin is a signal transduction regulatory factor which plays an important role in cell division and malignant tumor development. Our data suggest that stathmin may be a promising target molecule for blocking bone metastasis of breast cancer.

Novel technique of overlaying a poly-L: -lactic acid nanosheet for adhesion prophylaxis and fixation of intraperitoneal onlay polypropylene mesh in a rabbit model.

BACKGROUND: One problem with polypropylene mesh (PPM) used to repair abdominal wall hernias is dense adhesions to the visceral surface. The authors developed the biocompatible poly-L: -lactic acid (PLLA) nanosheet (thickness < 100 nm), which has the unique ability to adhere tightly to tissues but not to opposing tissues. This study investigated the antiadhesive and fixative characteristics of the PLLA nanosheet after placement of intraperitoneal onlay PPM (IPOM) overlaid with a PLLA nanosheet on intact peritoneum. METHODS: The PLLA nanosheet was fabricated by the spin-coating method and peeling technique with polyvinyl alcohol (PVA) as a supporting film. Two 1.5-cm-square pieces of mesh were implanted on each peritoneal side of the midline incision. The mesh was fixed to the peritoneum with a suture and then overlaid with a 4-cm-square piece of Seprafilm or nanosheet. To examine the fixative property, mesh was overlaid with Seprafilm or nanosheet without a fixed suture. After 4 weeks, mesh adhesion, inflammatory reaction, fixation, and dislocation of mesh were evaluated. RESULTS: Nanosheet-overlaid meshes were flexible and fit over the peritoneum. Adhesion was observed in 10% of the nanosheet-overlaid meshes and in 50% of the Seprafilm-overlaid meshes. The adhesion tenacity grade was significantly lower with the nanosheet-overlaid meshes (0.1 ± 0.1) than with the Seprafilm-overlaid meshes (1.0 ± 0.4) (p = 0.029), and the percentage of the adhesion area also was lower with the nanosheet-overlaid meshes (1.0 ± 1.0% vs 8.5 ± 3.2%; p = 0.037). The mean inflammatory cell counts were lower with the nanosheet-overlaid meshes (p = 0.0023). Regarding the fixative property, 37.5% of the nanosheet-overlaid meshes were fixated on the peritoneum, but no Seprafilm-overlaid mesh was fixated. CONCLUSION: Overlaying of a PLLA nanosheet was effective for adhesion prophylaxis of intraperitoneal mesh. It also may have a possible beneficial effect on fixation of mesh.

Two cases of acute poisoning with acetamiprid in humans.

INTRODUCTION: Acetamiprid is a potent and a relatively new neonicotinoid insecticide. Animal studies have indicated that it has a low toxicity to mammals. Despite wide usage, human exposure resulting in toxicity is quite limited, and this is the first report in the English literature about acute acetamiprid poisoning in humans. CASE DETAILS: We herein describe two cases of acute poisoning with an insecticide formulation containing acetamiprid for suicidal purposes. Both cases experienced severe nausea and vomiting, muscle weakness, hypothermia, convulsions, and clinical manifestations including tachycardia, hypotension, electrocardiogram changes, hypoxia, and thirst in the case with the higher serum concentration of acetamiprid. The symptoms were partially similar to acute organophosphate intoxication. Supportive treatments for a variety of symptoms were sufficient for recovery, and both individuals were discharged without any complications 2 days after ingestion.

Phytochelatins do not correlate with the level of Cd accumulation in Chlamydomonas spp.

Chlamydomonas acidophila KT-1 and Chlamydomonas acidophila DVB238 exhibit a strong heavy metal tolerance, but C. acidophila DVB238 can accumulate a much higher amount of Cadmium (Cd) than C. acidophila KT-1. Phytochelatins (PCs) are known to play an important role in the detoxification of several toxic heavy metals, but the relationship between PCs and Cd accumulation is not clear. PC metabolism and Cd accumulation were investigated by using three Chlamydomonas strains including Chlamydomonas reinhardtii C-9 as a standard alga. The results showed that the PC content did not correlate closely with the level of Cd accumulation, maintenance of a high GSH level seeming to be more important for Cd accumulation. The ultrastructure of C. acidophila KT-1 was extremely disrupted by a great increase in starch granules, which resulted in a moribund state, but hyper-accumulator C. acidophila DVB238 did not exhibit an increase in starch granules in its cells, in spite of Cd accumulation in its chloroplasts, cytosol and vacuoles. These results indicated that C. acidophila DVB238 probably has a developed detoxification system preventing such as destruction of the cells due to Cd toxicity.

Variations on a theme: diverse N-acyl homoserine lactone-mediated quorum sensing mechanisms in gram-negative bacteria.

Many Gram-negative bacteria employ a mechanism of cell-cell communication known as quorum sensing (QS). The role of QS is to enable the cells in a culture to coordinate their gene expression profile with changes in the population cell density. The best characterized mechanisms of QS employ N-acylated homoserine lactones (AHLs) as signalling molecules. These AHLs are made by enzymes known as LuxI homologs, and accumulate in the culture supernatant at a rate proportional to the increase in cell density. Once the AHL concentration exceeds a certain threshold value, these ligands bind to intracellular receptors known as LuxR homologs. The latter are transcriptional regulators, whose activity alters upon binding the AHL ligand, thereby eliciting a change in gene transcription. Over the last five years, it has become increasingly obvious that this is a rather simplistic view of AHL-dependent QS, and that in fact, there is considerable diversity in the way in which LuxI-R homologs operate. The aim of the current review is to describe these variations on the basic theme, and to show how functional genomics is revolutionizing our understanding of QS-controlled regulons.

Ultrastructural changes in Chlamydomonas acidophila (Chlorophyta) induced by heavy metals and polyphosphate metabolism.

Ultrastructural changes induced by heavy metals (cadmium, zinc, and copper) and polyphosphate metabolism were studied in Chlamydomonas acidophila. Transmission electron microscopy indicated that cadmium led to the most drastic morphometric changes. An increase in number and volume of starch grains and vacuoles as well as the presence of electron dense deposits in vacuole and membrane whorls were observed. Energy-dispersive X-ray analysis revealed that vacuolar deposits inside cells treated with cadmium contained phosphate and cadmium. These ultrastructural changes were accompanied by a change in the intracellular polyphosphate level, as shown by in vivo (31)P-nuclear magnetic resonance. It was also observed that cadmium treatment caused polyphosphate degradation and increased vacuolar short-chains and orthophosphates.