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The methodology used for analyzing the survival process should keep in mind heterogeneity in empirical data. Cross-sectional data are more heterogeneous in comparison with birth-cohort data. [ABSTRACT FROM AUTHOR]

Anaerobic fermentation converts organic waste into valuable products like volatile fatty acids (VFA). However, this process has weaknesses, such as delayed mass transfer, a slow microbe growth rate, poor hydrolysis, and surface heterogeneity. Such issues can be addressed by adding nanomaterials because they have unique physicochemical properties, such as a large surface area, many active sites, a high level of reactivity, a high level of specificity, the ability to self-assemble, and better mobility. This review focuses on the current efforts to investigate the effects of nanomaterials on improving VFA production. In addition, this work includes bibliometric information to aid in understanding current trends in this field of study. Furthermore, this work also reviewed the cytotoxicity and ecotoxicity of nanoparticles, followed by the applications and downstream processing of VFA. Finally, this paper discusses the reuse and recovery of several nanomaterials and provides a cost analysis. [ABSTRACT FROM AUTHOR]

Biochemical sensors have important applications in biology, chemistry, and medicine. Nevertheless, many biochemical sensors are hampered by intricate techniques, cumbersome procedures, and the need for labeling. In the past two decades, it has been discovered that liquid crystals can be used to achieve the optical amplification of biological interactions. By modifying recognition molecules, a variety of label-free biochemical sensors can be created. Consequently, biochemical sensors based on the amplification of liquid crystals have become one of the most promising sensors. This paper describes in detail the optical sensing principle of liquid crystals, sensing devices, and optical detection technologies. Meanwhile, the latest research findings are elucidated. Finally, the challenges and future research directions are discussed. [ABSTRACT FROM AUTHOR]

The new competency-based medical education undergraduate curriculum (CBMC) was launched for the 2019 admission batch of MBBS students. The programme is designed to create an "Indian Medical Graduate" (IMG) possessing the requisite knowledge, skills, attitudes, values and responsiveness, so that the graduate may function appropriately and effectively as a physician of first contact with the community while being globally relevant. Given that implementation of this curriculum is still in its infancy across the country, we stand to gain from a unified approach to its implementation. Phase I of the curriculum includes anatomy, physiology, and biochemistry along with professional and personal development modules. Biochemistry enjoys an enviable position in the medical curriculum as it explains the molecular basis of diseases. We present an appraisal of the curriculum in Biochemistry by reviewing the components against Harden's six themes which are considered when planning or developing a curriculum. Further, five core components of CBME are selected on the basis of three research papers to characterize underlying assumptions of CBME to suggest ways of logical implementation for achieving the competencies expected of the Indian Medical Graduate. The insight gained shall help students to be equipped with competencies which they shall be able to use in their day- to- day work, which shall ultimately help benefit patient care and the society at large. [ABSTRACT FROM AUTHOR]

This paper shows a novel approach and a new model to find the relation of formulas between the thermodynamic parameters and electromagnetic parameters, directly and indirectly. Effectiveness of formulas is discussed by considering issues: no thermoregulation process (including body metabolism), no heat transfer consideration, and the Heating loss has not occurred and boundary conditions in a closed system. The enthalpy, internal energy, and Gibbs free energy are perfect indicators for describing bio-reaction in the human body. Because they are state functions (they are independent of intermediate steps, just first and final steps), they are affected by the SAR estimation that represents the absorption power throughout human tissue. These formulas brought in many features to control body reactions or Krebs cycle. Moreover, the derived formulas convert the reaction from non-spontaneous to spontaneous form by converting Gibbs free energy to a negative value. According to findings, the model can be applied in across many disciplines, such as medical treatment, lipid decomposition, cancer healing, and physical therapy. And in the end, as a result of an increase in the concentration of electromagnetic waves in the atmosphere due to technological development, which urges urgently to amend and update all equations to take into account the effect of magnetic waves in all disciplines affected by them. [ABSTRACT FROM AUTHOR]

Franklin was no victim in how the DNA double helix was solved. An overlooked letter and an unpublished news article, both written in 1953, reveal that she was an equal player. [ABSTRACT FROM AUTHOR]

The giant anteater (Myrmecophaga tridactyla) is classified as a vulnerable species but is commonly received in rescue centers and zoos. Establishing hematological and biochemical reference intervals of free-ranging animals is an important tool to assess the health of both captive and wild populations. Reference values for 53 free-ranging giant anteaters in the Cerrado savanna of Mato Grosso do Sul state were established and differences across sexes and age groups were tested. Significant differences (p ≤ 0.05) between age groups (juvenile and adult) were found for hematocrit, mean corpuscular hemoglobin concentration (MCHC), lymphocytes, monocytes, platelets, total protein, globulin, alkaline phosphatase (ALP), glutamyl transpeptidase (GGT), and phosphorus. Between sexes, the only value that showed a significant difference was platelets. The data from the present study were also compared with previous studies and a worldwide zoological databank (ZIMS). White blood cell values were higher in all the studies with free-ranging giant anteaters compared to captive individuals. The relative eosinophils reference interval from our study was the highest ever reported for the species. This paper is the first published study with biochemical values for free-ranging giant anteaters and provides important reference intervals for future giant anteater in situ and ex situ conservation initiatives and highlights the importance of more veterinary research with comparative aspects between wild and captive animals. [ABSTRACT FROM AUTHOR]

Summary: Kew's Jodrell Laboratory was established in 1876 as a centre for botanical research in disciplines including plant physiology, anatomy and embryology, palaeobotany and mycology. Despite relatively little available funding, its location in one of the world's largest botanic gardens and close to several well-curated plant collections has ensured its continued existence for almost a century and a half. Under the far-sighted leadership of Kew's second Director, Joseph Dalton Hooker, the Jodrell Laboratory was established to coincide with Thomas Henry Huxley's pioneering course at the Normal School of Science in London. Funded by a generous private donation, the Laboratory complemented and augmented the programme in taxonomy and systematics already established in Kew's Herbarium, and provided a broader educational and research base to explore contemporary laboratory-based discoveries in fields such as physiology and lifecycles (sometimes termed the "New Botany"). The Jodrell Laboratory represents one of the world's first non-university affiliated laboratories and has spawned several "spin-off" facilities such as the Laboratory of Plant Pathology and the Millennium Seed Bank. This paper traces its early influence as an important centre for research in palaeobotany and plant systematics, its subsequent decline during the inter-war years, and a relatively dynamic period of innovative research following the construction of a new building on the same site. [ABSTRACT FROM AUTHOR]

Phytic acid (PA) is an abundant natural plant component that exhibits a versatility of applications benefited from its chemical structure, standing out its use as food, packing and dental additive due to its antimicrobial properties. The capacity of PA to chelate ions is also well-established and the formation and thermodynamic properties of different metallic complexes has been described. However, research studies of these compounds in terms of chemistry and biological features are still demanded in order to extend the application scope of PA complexes. The main goal of this paper is to deepen in the knowledge of the bioactive metal complexes chemistry and their bactericide activity, to extend their application in biomaterial science, specifically in oral implantology. Thus, this work presents the synthesis and structural assessment of two metallic phytate complexes bearing the bioactive cations Zn2+ and Sr2+ (ZnPhy and SrPhy respectively), along with studies on the synergic biological properties between PA and cations. Metallic phytates were synthesized in the solid-state by hydrothermal reaction leading to pure solid compounds in high yields. Their molecular formulas were C6H12024P6Sr4·5H2O and C6H12024P6Zn6·6H2O, as determined by ICP and HRES-TGA. The metal coordination bond of the solid complexes was further analysed by EDS, Raman, ATR-FTIR and solid 13C and 31P-NMR spectroscopies. Likewise, we evaluated the in vitro ability of the phytate compounds for inhibiting biofilm production of Streptococcus mutans cultures. Results indicate that all compounds significantly reduced biofilm formation (PA < SrPhy < ZnPhy), and ZnPhy even showed remarkable differences with respect to PA and SrPhy. Analysis of antimicrobial properties shows the first clues of the possible synergic effects created between PA and the corresponding cation in different cell metabolic processes. In overall, findings of this work can contribute to expand the applications of these bioactive metallic complexes in the biotechnological and biomedical fields, and they can be considered for the fabrication of anti-plaque coating systems in the dentistry field. [ABSTRACT FROM AUTHOR]

The paper discusses the core ideas and the development of biogeochemistry as an integrated research avenue in geochemistry and biology created by V.I. Vernadsky. Much attention is paid to the key concepts of biogeochemistry: living matter, the biogenic migration of chemical elements, and the chemical elemental composition of organisms and its ecological significance. The development of the various functions of the biosphere is analyzed: ecological, concentrational, and informational. The differentiation of the chemical elemental composition of organisms is analyzed under conditions when the biosphere is impacted by anthropogenic activities (the development of industries). The role of biogeochemistry is demonstrated with reference to the development of biotechnologies and the elaboration of a biogeochemical indication of the ecological state of biospheric taxons. The progress in biogeochemistry and its current problems are briefly analyzed. [ABSTRACT FROM AUTHOR]

Evolution by natural selection peerlessly describes how life's complexity develops — but can it be explained in terms of physics? A new approach suggests it can. Radical theory explains how physics creates all biology's complexity. [ABSTRACT FROM AUTHOR]

The story of how the structure of DNA was found is one of team science from which one member was unforgivably excluded. [ABSTRACT FROM AUTHOR]

This study employs machine learning to detect the severity of major depressive disorder (MDD) through binary and multiclass classifications. We compared models that used only biomarkers of oxidative stress with those that incorporate sociodemographic and health-related factors. Data collected from 830 participants, based on the Patient Health Questionnaire (PHQ-9) score, inform our analysis. In binary classification, the Random Forest (RF) classifier achieved the highest Area Under the Curve (AUC) of 0.84 when all features were included. In multiclass classification, the AUC improved from 0.84 with only oxidative stress biomarkers to 0.88 when all characteristics were included. To address data imbalance, weighted classifiers, and Synthetic Minority Over-sampling Technique (SMOTE) approaches were applied. Weighted random forest (WRF) improved multiclass classification, achieving an AUC of 0.91. Statistical tests, including the Friedman test and the Conover post-hoc test, confirmed significant differences between model performances, with WRF using all features outperforming others. Feature importance analysis shows that oxidative stress biomarkers, particularly GSH, are top ranked among all features. Clinicians can leverage the results of this study to improve their decision-making processes by incorporating oxidative stress biomarkers in addition to the standard criteria for depression diagnosis. [ABSTRACT FROM AUTHOR]

The protein NINJ1 drives membrane rupture associated with certain types of cell death. Investigation of NINJ1 reveals mechanistic details of how it functions, raising the possibility of developing new therapeutics.Insights into a mechanism that ruptures the plasma membrane. [ABSTRACT FROM AUTHOR]

During the past two decades, philosophers of biology have increasingly turned their attention to mechanisms of biological phenomena. Through analyses of mechanistic proposals advanced by biologists, the goal of these philosophers is to understand what a mechanism is and how mechanisms explain. These analyses have generally focused on mechanistic proposals for phenomenon that occur at the cellular or sub-cellular level, such as synapse firing, protein synthesis, or metabolic pathway operation. Little is said about the mechanisms of the macromolecular reactions that underpin these phenomena. These reactions comprise a diverse family of reaction types, and include protein folding, macromolecular complex formation, receptor-ligand interactions, and enzyme catalysis. In this paper, I develop an account of mechanism that focuses exclusively on macromolecular reactions. I begin by reviewing how mechanism is understood in enzymology, and how mechanistic concepts of enzymology apply to macromolecular reactions in general. We will see that the mechanism of a macromolecular reaction is most accurately described as a progression of reaction intermediates, where the evolution of intermediates, from one to the next, is characterized by an energetic coupling between chemistry and protein dynamics. I then make the case that this description necessitates a grounding in a process ontology. To describe the mechanism by which a macromolecular reaction occurs is to describe a process. [ABSTRACT FROM AUTHOR]

Introduction: The development of several experimental migraine provocation models has significantly contributed to an understanding of the signaling mechanisms of migraine. The early history of this development and a view to the future are presented as viewed by the inventor of the models. Methods: Extensive knowledge of the literature was supplemented by scrutiny of reference lists. Results: Early studies used methodologies that were not blinded. They suggested that histamine and nitroglycerin (Glyceryl trinitrate, GTN) could induce headache and perhaps migraine. The development of a double blind, placebo-controlled model, and the use of explicit diagnostic criteria for induced migraine was a major step forward. GTN, donor of nitric oxide (NO), induced headache in people with- and without migraine as well as delayed migraine attacks in those with migraine. Calcitonin gene-related peptide (CGRP) did the same, supporting the development of CGRP antagonists now widely used in patients. Likewise, pituitary adenylate cyclase activating peptide (PACAP) provoked headache and migraine. Recently a PACAP antibody has shown anti migraine activity in a phase 2 trial. Increase of second messengers activated by NO, CGRP and PACAP effectively induced migraine. The experimental models have also been used in other types of headaches and have been combined with imaging and biochemical studies. They have also been used for drug testing and in genetic studies. Conclusion: Conclusion. Human migraine provocation models have informed about signaling mechanisms of migraine leading to new drugs and drug targets. Future use of these models in imaging-, biochemistry- and genetic studies as well as in the further study of animal models is promising. [ABSTRACT FROM AUTHOR]

As natural landscapes are modified and converted into simplified agricultural landscapes, the community composition and interactions of organisms persisting in these modified landscapes are altered. While many studies examine the consequences of these changing interactions for crops, few have evaluated the effects on wild plants. Here, we examine how pollinator and herbivore interactions affect reproductive success for wild resident and phytometer plants at sites along a landscape gradient ranging from natural to highly simplified. We tested the direct and indirect effects of landscape composition on plant traits and reproduction mediated by insect interactions. For phytometer plants exposed to herbivores, we found that greater landscape complexity corresponded with elevated herbivore damage, which reduced total flower production but increased individual flower size. Though larger flowers increased pollination, the reduction in flowers ultimately reduced plant reproductive success. Herbivory was also higher in complex landscapes for resident plants, but overall damage was low and therefore did not have a cascading effect on floral display and reproduction. This work highlights that landscape composition directly affects patterns of herbivory with cascading effects on pollination and wild plant reproduction. Further, the absence of an effect on reproduction for resident plants suggests that they may be adapted to their local insect community. [ABSTRACT FROM AUTHOR]

The hematological alterations of bovine reticular abscess are reported in literature, but the detailed biochemical alterations and long-term outcome of bovine reticular abscess have not been reported so far and are not available in the standard textbooks. This study aims to describe clinical features, hemato-biochemical alterations, management, productive and reproductive performance, long term follow-up of reticular abscess in bovines. This prospective study was conducted on 12 bovines diagnosed with reticular abscess. All the animals were subjected to hematological and biochemical evaluation along with a healthy control group. The diseased animals were subjected to radiography, ultrasonography, and surgical treatment. The clinical findings were chronic anorexia, dehydration, persistent or recurrent tympany, scanty feces, mushy rumen, tachypnea, gradual reduction in milk yield, distended rumen, and increased fecal particle size with undigested particles in feces. Although the presence of penetrating reticular foreign bodies seemed to be the major cause, the role of non-metallic foreign bodies cannot be ruled out. Ultrasonography was more reliable than radiography in the diagnosis of reticular abscess. The majority of the reticular abscesses were single and were located cranio-ventrally. White blood cell and neutrophil counts were significantly (p < 0.05) higher while lymphocyte count was significantly (p < 0.05) lower than the control values. The hematology findings can be used for tentative diagnosis of reticular abscess in bovines. Total bilirubin, aspartate aminotrasferase, total protein, globulin, fibrinogen, blood urea nitrogen, creatinine glucose, cholesterol, and lactate were significantly (p < 0.05) higher, and albumin, albumin-globulin ratio, fibrinogen ratio, potassium, chloride, and calcium were significantly (p < 0.05) lower than the corresponding control values. Rumen chloride concentration was higher than the reference range. Peritoneal fluid analysis in four cases revealed septic peritonitis. Reticular abscess can lead to vagal indigestion, usually posterior functional stenosis. The conservative treatment was unsuccessful. The long-time survival rate in surgically treated animals was 66.7% and in the majority of animals, there was no effect on fetal survival or milk yield in current and subsequent lactation. Reticular abscess was primarily associated with foreign bodies in the reticulum and causes significant biochemical changes. Ultrasonography was more reliable than radiography in the diagnosis of reticular abscess. Surgical drainage into the reticular lumen usually results in a successful surgical outcome. [ABSTRACT FROM AUTHOR]

Acetophenones are naturally occurring phenolic compounds which have found in over 24 plant families and also fungi strains. They are exist in both free or glycosides form in nature. The biological activities of these compounds have been assayed and reported including cytotoxicity, antimicrobial, antimalarial, antioxidant and antityrosinase activities. Herein, we review the chemistry and biological activity of natural acetophenone derivatives that have been isolated and identified until January 2024. Taken together, it was reported 252 acetophenone derivatives in which the genera Melicope (69) and Acronychia (44) were the principal species as producers of acetophenones. [ABSTRACT FROM AUTHOR]

As known "ecosystem engineers", beavers influence river hydrology, geomorphology, biochemistry, and biological assemblages. However, there is a lack of research regarding the effects of beaver activities on freshwater meiofauna. In this study, we investigated the taxonomic and functional composition of the benthic copepod assemblage of a segment of the Tiber River (Italy) where a beaver dam, created about 7 weeks before our survey, had formed a semi-lentic habitat upstream and a lotic habitat downstream of the dam. We also analyzed the copepod assemblage before and after a flood event that destroyed the beaver dam, providing a unique opportunity to observe changes in a naturally reversing scenario. Our analyses revealed that, while the taxonomic composition and functional traits of the copepod assemblage remained largely unchanged across the recently formed semi-lentic and lotic habitats, substantial differences were evident between the dammed and undammed states. The dammed state showed lower copepod abundances, biomass, and functionality than the undammed one. These results highlight the role of beaver dams in changing the composition and functionality of meiofaunal assemblages offering insights into the dynamic interactions within aquatic ecosystems. [ABSTRACT FROM AUTHOR]

Cell segregation allows the compartmentalization of cells with similar fates during morphogenesis, which can be enhanced by cell fate plasticity in response to local molecular and biomechanical cues. Endothelial tip cells in the growing retina, which lead vessel sprouts, give rise to arterial endothelial cells and thereby mediate arterial growth. Here, we have combined cell type-specific and inducible mouse genetics, flow experiments in vitro, single-cell RNA sequencing and biochemistry to show that the balance between ephrin-B2 and its receptor EphB4 is critical for arterial specification, cell sorting and arteriovenous patterning. At the molecular level, elevated ephrin-B2 function after loss of EphB4 enhances signaling responses by the Notch pathway, VEGF and the transcription factor Dach1, which is influenced by endothelial shear stress. Our findings reveal how Eph-ephrin interactions integrate cell segregation and arteriovenous specification in the vasculature, which has potential relevance for human vascular malformations caused by EPHB4 mutations. Arteries are vital blood vessels for our body and their growth and patterning are critical for proper blood flow. Here they use a retina model to show that a balance of EphB4 receptor and ephrin-B2 ligand integrate a well-wired molecular network to control arteriovenous patterning and vascular growth. [ABSTRACT FROM AUTHOR]

Phthorimaeaabsoluta is an invasive solanaceous plant pest with highly devastating effects on tomato plant. Heavy reliance on insecticide use to tackle the pest has been linked to insecticide resistance selection in P.absoluta populations. To underline insights on P.absoluta insecticide resistance mechanisms to diamides and avermectins, we evaluated the transcriptomic profile of parental (field-collected) and F8 (lab-reared) populations. Furthermore, to screen for the presence of organophosphate and pyrethroid resistance, we assessed the gene expression levels of acetylcholinesterase (ace1) and para-type voltage-gated sodium channel (VGSG) genes in the F1 to F8 lab-reared progeny of diamide and avermectin exposed P.absoluta field-collected populations. The VGSG gene showed up-regulation in 12.5% and down-regulation in 87.5% of the screened populations, while ace1 gene showed up-regulation in 37.5% and down-regulation in 62.5% of the screened populations. Gene ontology of the differentially expressed genes from both parental and eighth generations of diamide-sprayed P.absoluta populations revealed three genes involved in the metabolic detoxification of diamides in P.absoluta. Therefore, our study showed that the detoxification enzymes found could be responsible for P.absoluta diamide-based resistance, while behavioural resistance, which is stimulus-dependent, could be attributed to P.absoluta avermectin resistance. [ABSTRACT FROM AUTHOR]

This study was designed to evaluate the effects of multi-strain probiotic (MSP) on growth, whole-body composition, digestive and antioxidant enzymes, hematology, blood biochemistry, and physiological stress responses in Clarias batrachus fingerlings. Five experimental diets were prepared with supplementation of MSP (composed of Bacillus subtilis, B. licheniformis, and Enterococcus faecalis) powder at 0.5, 1.0, 1.5, and 2.0 g/kg. Healthy fingerlings (N = 225) were procured from a fish hatchery and acclimatized to laboratory conditions for 15 days. After acclimation, the fingerlings (10.13 ± 0.01 g; mean ± SD) were randomly stocked into five experimental groups (15 fish/aquarium) with three replicates and provided with experimental diets at a 5% body weight ration five times a day for 90 days. Fish fed with 2.0 g/kg MSP diets showed significantly higher growth performance in terms of weight gain % (493.98 ± 6.3%) and specific growth rate (1.97 ± 0.01%/day) and the lowest feed conversion ratio (1.72 ± 0.01) in comparison to the control (299.73 ± 5.17%, 1.53 ± 0.01%/day, and 2.28 ± 0.05, respectively). Similarly, higher activities (p < 0.05) of amylase (1.96 ± 0.02 U/mg protein), protease (10.51 ± 0.06 U/mg protein) and lipase (2.26 ± 0.02 U/mg protein) were also observed in the group fed 2.0 g/kg MSP than in the control group (1.20 ± 0.01, 8.61 ± 0.01, and 1.55 ± 0.02 U/mg protein, respectively). Dietary supplementation significantly (p < 0.05) enhanced the activities of superoxide dismutase (5.86 ± 0.04 U/mg prot), catalase (85.54 ± 0.58 U/mg prot), and glutathione peroxidase (105.69 ± 0.17 μU/mg prot) and reduced the malondialdehyde content (2.13 ± 0.06 mg/g prot) in fish fed 2.0 g/kg MSP-supplemented diets compared to the control group (4.54 ± 0.08 U/mg prot, 70.24 ± 0.53 U/mg prot, 89.61 ± 0.32 μU/mg prot, and 2.77 ± 0.02 mg/g prot, respectively). Dietary MSP did not affect the survival rate and proximate composition of fish. Hematological parameters such as white blood cells, red blood cells, hemoglobin, and hematocrit were also significantly increased in response to MSP supplementation in diets. Moreover, an increasing trend in blood biochemistry was observed in the activities of alanine phosphatase, while a decrease in alanine aminotransferase and aspartate aminotransferase was observed. It is concluded that MSP supplementation up to 2.0 g/kg showed promising results on C. batrachus fingerlings. MSP supplementation significantly enhanced the growth performance, antioxidant and digestive enzyme activities, blood biochemistry, and hematological parameters of C. batrachus compared to the control. The physiological stress response did not show any significant alteration. Thus, MSP can be effectively recommended as an effective growth promotor for fish. [ABSTRACT FROM AUTHOR]

An unusual form of cell death called ferroptosis can sweep over embryonic tissues in a wave-like manner to ensure proper muscle development — evidence that ferroptosis has a role in normal physiology.Iron-dependent cell death sweeps across tissue to shape embryonic muscle. [ABSTRACT FROM AUTHOR]

High-resolution structures of TAAR1 — the receptor bound by amphetamines and molecules called trace amines — reveal detailed interactions with ligand molecules that will inform efforts to design antipsychotic drugs. Insight into how ligand molecules bind to the TAAR1 receptor. [ABSTRACT FROM AUTHOR]

Objective: To study the in vitro and in vivo antitumor effects of the polysaccharide of Alocasia cucullata (PAC) and the underlying mechanism. Methods: B16F10 and 4T1 cells were cultured with PAC of 40 µg/mL, and PAC was withdrawn after 40 days of administration. The cell viability was detected by cell counting kit-8. The expression of Bcl-2 and Caspase-3 proteins were detected by Western blot and the expressions of ERK1/2 mRNA were detected by quantitative real-time polymerase chain reaction (qRT-PCR). A mouse melanoma model was established to study the effect of PAC during long-time administration. Mice were divided into 3 treatment groups: control group treated with saline water, positive control group (LNT group) treated with lentinan at 100 mg/(kg·d), and PAC group treated with PAC at 120 mg/(kg·d). The pathological changes of tumor tissues were observed by hematoxylin-eosin staining. The apoptosis of tumor tissues was detected by TUNEL staining. Bcl-2 and Caspase-3 protein expressions were detected by immunohistochemistry, and the expressions of ERK1/2, JNK1 and p38 mRNA were detected by qRT-PCR. Results: In vitro, no strong inhibitory effects of PAC were found in various tumor cells after 48 or 72 h of administration. Interestingly however, after 40 days of cultivation under PAC, an inhibitory effect on B16F10 cells was found. Correspondingly, the long-time administration of PAC led to downregulation of Bcl-2 protein (P<0.05), up-regulation of Caspase-3 protein (P<0.05) and ERK1 mRNA (P<0.05) in B16F10 cells. The above results were verified by in vivo experiments. In addition, viability of B16F10 cells under long-time administration culture in vitro decreased after drug withdrawal, and similar results were also observed in 4T1 cells. Conclusions: Long-time administration of PAC can significantly inhibit viability and promote apoptosis of tumor cells, and had obvious antitumor effect in tumor-bearing mice. [ABSTRACT FROM AUTHOR]

Proteins spanning the membranes of cells of the intestine and kidney use sodium-ion gradients to take up glucose, enabling water absorption, too. The structures of these transporter proteins have now been observed in detail.Human sodium-coupled glucose transporters seen in detail. [ABSTRACT FROM AUTHOR]

The bacterial Makes caterpillars floppy 1 (Mcf1) toxin promotes apoptosis in insects, leading to loss of body turgor and death. The molecular mechanism underlying Mcf1 intoxication is poorly understood. Here, we present the cryo-EM structure of Mcf1 from Photorhabdus luminescens, revealing a seahorse-like shape with a head and tail. While the three head domains contain two effectors, as well as an activator-binding domain (ABD) and an autoprotease, the tail consists of two putative translocation and three putative receptor-binding domains. Rearrangement of the tail moves the C-terminus away from the ABD and allows binding of the host cell ADP-ribosylation factor 3, inducing conformational changes that position the cleavage site closer to the protease. This distinct activation mechanism that is based on a hook-loop interaction results in three autocleavage reactions and the release of two toxic effectors. Unexpectedly, the BH3-like domain containing ABD is not an active effector. Our findings allow us to understand key steps of Mcf1 intoxication at the molecular level. The bacterial toxin Makes caterpillars floppy 1 promotes apoptosis in insects. Combining single-particle cryo-EM and biochemistry, the authors determined the molecular architecture of the toxin and revealed its autoproteolytic activation mechanism. [ABSTRACT FROM AUTHOR]

Purpose: The obese black and tan, brachyuric (BTBR) ob/ob mouse spontaneously develops features comparable to human diabetic nephropathy. The primary aim of the present study was to investigate if a diet containing fish proteins would attenuate or delay the development of glomerular hypertrophy (glomerulomegaly), mesangial sclerosis and albuminuria in obese BTBR ob/ob mice. Methods: Obese BTBR.CgLepob/WiscJ male mice were fed diets containing 25% of protein from Atlantic cod backbones and 75% of protein from casein (Cod-BB group), or casein as the sole protein source (control group). Kidneys were analysed morphologically, and markers for renal dysfunction were analysed biochemically in urine and serum. Results: The Cod-BB diet attenuated the development of mesangial sclerosis (P 0.040) without affecting the development of glomerular hypertrophy and albuminuria. The urine concentration of cystatin C (relative to creatinine) was lower in mice fed the Cod-BB diet (P 0.0044). Conclusion: A diet containing cod backbone protein powder attenuated the development of mesangial sclerosis and tubular dysfunction in obese BTBR ob/ob mice, but did not prevent the development of glomerular hypertrophy and albuminuria in these mice. [ABSTRACT FROM AUTHOR]

Objectives: Overconsumption of non-nutritive sweeteners is associated with obesity, whereas the underlying mechanisms remain controversial. This study aimed to investigate the effects of long-term consumption of nutritive or non-nutritive sweeteners with or without high fat diet on sweet taste receptor expression in nutrient-sensing tissues and energy regulation dependent on sweet-sensing. Methods: 50 Male Sprague–Dawley rats (140–160 g) were assigned to 10 groups (n = 5/group). All received fructose at 2.5% or 10%, sucralose at 0.01% or 0.015% or water with a normal chow diet or high fat diet for 12 weeks. Food and drink intake were monitored daily. Oral glucose tolerance test and intraperitoneal glucose tolerance test were performed at week 10 and 11 respectively. Serum was obtained for measurement of biochemical parameters. Tongue, duodenum, jejunum, ileum, colon and hypothalamus were rapidly removed to assess gene expression. Results: Long-term consumption of sweeteners impaired glucose tolerance, increased calorie intake and body weight. A significant upregulation of sweet taste receptor expression was observed in all the four intestinal segments in groups fed 0.01% sucralose or 0.015% sucralose, most strikingly in the ileum, accompanied by elevated serum glucagon-like peptide-1 levels and up-regulated expression of sodium-dependent glucose cotransporter 1 and glucose transporter 2. A significant down-regulation in the tongue and hypothalamus was observed in groups fed 10% fructose or 0.015% sucralose, with alterations in hypothalamic appetite signals. The presence of high fat diet differentially modulates sweet taste perception in nutrient-sensing tissues. Conclusions: Long-term consumption of whether nutritive sweeteners or non-nutritive sweeteners combined with high fat diet contribute to dysregulation of sweet taste receptor expression in oral, intestinal and central nervous tissues. [ABSTRACT FROM AUTHOR]

Savannas are characterized by the co-occurrence of two different plant life forms: grasses and trees. Herbivory plays a major role in the balance between grasses and trees in savanna ecosystems. The present study aimed to investigate the impact and interactions between long-term (i.e. 20 years) herbivory and/or its exclusion and plant life form on the soil biochemistry of a protected semi-arid savanna ecosystem in the Kruger National Park (KNP), South Africa. To study the effects of herbivory on soil properties, herbivore exclosures (fully fenced areas, partially fenced areas, and an unfenced area) were used in conjunction with plant life form (trees and grasses) were considered. Interaction effects of herbivory and plant life form on soil pH, electrical conductivity (EC), total nitrogen (TN), total carbon (TC), available phosphorus (available P), exchangeable cations (K+, Na+, Mg2+ and Ca2+) cation exchange capacity (CEC), organic matter (OM) and total microbial activity were determined on savanna soils in the Nkuhlu exclosures, KNP. Exclosures where herbivores were present had significantly higher soil pH, The presence of herbivores caused an increase in soil pH, EC, exchangeable Na, CEC, and OM. The influence of the tree canopy was significantly more pronounced in elevating total C and N, exchangeable K+, Mg2+ and Ca2+, CEC and OM than observed in the open grassland zones across all exclosures. The two-way interaction between herbivory and plant life form resulted in significant decreases in TN, TC, exchangeable K, Na and Mg in open grassland areas outside of herbivore exclosures where large animals had direct access, as compared to areas within the exclosures which was protected from animal entry herbivory. This data can be used by national parks as an indicator to increase their knowledge of environmental issues relating to maintaining and preserving landscape features of savannas. [ABSTRACT FROM AUTHOR]

Today, the University of Tartu (earlier Dorpat) belongs among the 250 best universities of the world. Its international team of pharmacologists uses powerful confocal microscopes to study apoptosis and cell death within an international consortium. Science is working on solutions to fight Alzheimer disease, which is a torture for humankind. For this to happen today, the foundation was laid by scientists of previous centuries who deserve our great respect, all of them together and everyone separately. Johannes Piiper, a well-known professor of physiology, once told me in a conversation that articles should be published in every 10 years about the men who have served as examples for the science of the present-day world and about the conditions in which their research was done. It is essential that researchers working in modern laboratories would not forget in their smugness that the laboratory has not always been a warm and well-lit room full of expensive technology, and not always have millions been allocated for research grants. Electricity came to Dorpat as late as in 1892. In the harsh Estonian winter, ice sometimes covered the inner walls of the Old Anatomical Theatre. Dorpat received railway connection in 1876. When I have made presentations in American countries, I have repeatedly been asked why the pharmacologists of the University of Tartu have not published an illustrated biography of Rudolf Richard Buchheim. As I have worked in the rooms the construction of which was directed by R. Buchheim as Dean of the Faculty of Medicine, I am trying to correct this shortcoming at least to some extent. I have written about Buchheim earlier, but then the print volume was limited. In this article, I have attempted to fill the gaps where the earlier materials have been erroneous or incomplete. So, the article will explain the formation of the large family of Buchheims. Several articles have given the impression that when Buchheim arrived in Dorpat, there were no facilities at all, and, therefore, he founded the laboratory in the basement of his dwelling house. This article will also bring clarity to that. Through O. Schmiedeberg's memories, we will see the great difficulties with which Buchheim's viewpoints broke through and were accepted. The question where Buchheim's laboratory was situated after Buchheim moved house in 1852 until the completion of the annex to the Old Anatomical Theatre in 1860 will also be answered. The article also brings some clarity about R. Buchheim's children. For the first time, it has been summed up how R. Buchheim is commemorated in different towns and countries. The article includes photos from Estonian and foreign archives; some photos have also been received from cooperation partners. Photos available on the Internet as freeware have also been used. The mid-nineteenth century brought a whole constellation of talented scientists to the German-language University of Dorpat (now Tartu in Estonia, founded 1632) on the outskirts of the Russian Empire. They did not tinker on their own but were engaged in successful cooperation. Thus, the celebrities who happened to work in Tartu simultaneously included Professor of Anatomy and Physiology Georg Friedrich Karl Heinrich Bidder; founder of physiological chemistry, chemist Carl Ernst Heinrich Schmidt; and Rudolf Richard Buchheim whom Professors E. A. Carus and F. Bidder had invited to Tartu to work as Head of the Department of Materia Medica, Dietetics and History of Medicine. Together, the three talented and hardworking scientists cleared the path to research-based medicine and wrote their names into the history of world medicine forever. By introducing chemical analysis and animal experiments, R. Buchheim laid the foundation to scientific pharmacology. [ABSTRACT FROM AUTHOR]

The biomass composition of kelp varies within species both spatially and temporally. However, this variation in biomass quality has not yet been investigated for the native kelp Ecklonia radiata within New Zealand, where the kelp is a target for the emerging seaweed aquaculture industry. In this study we quantified spatial and temporal variation in the composition of E. radiata biomass, collected from 12 sites around the North Island of New Zealand and from 12 months across a full year at a single site (n = 138). High spatial variation was detected for most components, including alginate (range: 16.6 – 22.7% DW, n = 12), fucoidan (range: 1.2 – 1.6% DW, n = 12), phlorotannins (range: 4.8 – 9.3% DW, n = 72), and glucose (range: 9.3 – 22.6% DW, n = 12). The biomass composition of E. radiata varied significantly among sites but with no clear patterns among regions, indicating that geographic differences were mostly local rather than regional, possibly due to site-specific environmental conditions. Significant temporal variation (measured by positive autocorrelation between months) was detected in the content of lipids, proteins, glucose, guluronic acid, nitrogen, phosphorous, iodine, arsenic, and mercury, and for the mannuronic to guluronic acid (M:G) ratio. Overall, E. radiata had comparable biomass composition to that of commercially grown northern hemisphere species but with substantially higher phlorotannin content. These results demonstrate that E. radiata could be a viable southern hemisphere alternative for a broad range of commercial applications. [ABSTRACT FROM AUTHOR]

Chinese medicine (CM) is an important resource for human life understanding and discovery of drugs. However, due to the unclear pharmacological mechanism caused by unclear target, research and international promotion of many active components have made little progress in the past decades of years. CM is mainly composed of multi-ingredients with multi-targets. The identification of targets of multiple active components and the weight analysis of multiple targets in a specific pathological environment, that is, the determination of the most important target is the main obstacle to the mechanism clarification and thus hinders its internationalization. In this review, the main approach to target identification and network pharmacology were summarized. And BIBm (Bayesian inference modeling), a powerful method for drug target identification and key pathway determination was introduced. We aim to provide a new scientific basis and ideas for the development and international promotion of new drugs based on CM. [ABSTRACT FROM AUTHOR]

How do mitochondrial organelles remove damaged parts of inner membrane for recycling in the cytoplasm? The discovery of an exit route that flips inner membrane outside the organelle provides some answers. Pathway selectively removes inner membrane from mitochondrial organelles. [ABSTRACT FROM AUTHOR]

Proteins have been designed that assemble in different ways depending on whether an ‘effector’ molecule is present — a demonstration of allostery, the phenomenon that enables switch-like control of protein functions in nature.Designer proteins that exhibit the phenomenon of allostery. [ABSTRACT FROM AUTHOR]

Precursor messenger RNA is edited into its final form by an RNA–protein assembly called the spliceosome. Structural evidence provides insights into how the spliceosome is disassembled when its job is complete.Structural evidence reveals key steps during spliceosome disassembly. [ABSTRACT FROM AUTHOR]

As a tech-hungry world gobbles up rare-earth elements, researchers are adapting bacteria that can isolate and purify the metals in the absence of harsh chemicals. [ABSTRACT FROM AUTHOR]

One of the most significant environmental challenges in the twenty-first century is heavy metal pollution. The potential use of fresh Azolla pinnata to alleviate the toxic effects of Cd and Co on the germination measurements of wheat seeds (Triticum aestivum L.) and the biochemistry of seedlings was studied. Two concentrations (80 and 100 mg L−1 solutions) of CdNO3 and CoCl2 were used before and after treatment with A. pinnata. The highest removal efficiency (RE) by A. pinnata was obtained on the fifth day, with a Cd RE = 55.9 and 49.9% at 80 and 100 mg L−1, respectively. Cadmium and cobalt solutions reduced the germination percentage, and the measured variables of wheat seeds meanwhile increased the radicle phytotoxicity. In contrast, the presence of A. pinnata in the germination medium increased all the measured variables and decreased radicle phytotoxicity. At 80 and 100 mg L−1, Cd significantly reduced the fresh and dry biomass, and height of wheat seedlings after 21 days of cultivation compared to Co. Cadmium and high concentrations of cobalt increased the contents of H2O2, proline, MDA, phenolic, and flavonoid compounds. The application of treated Cd and Co solutions by A. pinnata showed a decrease in H2O2, proline, phenolic, and flavonoid compounds levels accompanied by a reduction in catalase and peroxidase activities compared to the control. This study showed the positive role of A. pinnata in alleviating the metal impacts, particularly Cd, on the seedling growth of wheat and its germination. [ABSTRACT FROM AUTHOR]

Background: Erenumab has demonstrated effectiveness for prevention of migraine attacks, but the treatment is costly, and a considerable proportion of patients do not respond to it. The Registry for Migraine study (REFORM) was initiated to discover biomarkers that can predict response to erenumab in patients with migraine. The specific objective was to investigate differences in erenumab efficacy based on clinical information, blood-based biomarkers, structural and functional magnetic resonance imaging (MRI), and response to intravenous infusion of calcitonin gene-related peptide (CGRP). In this first report of the REFORM study, we provide a comprehensive description of the study methodology, and present the baseline characteristics of the study population. Methods: The REFORM study was a single-center, prospective, longitudinal cohort study in adults with migraine who were scheduled to receive preventive treatment with erenumab as part of a separate, open-label, single-arm phase IV trial. The study included four periods: a 2-week screening period (Weeks -6 to -5), 4-week baseline period (Week -4 to Day 1), 24-week treatment period (Day 1 to Week 24), and a 24-week follow-up period without treatment (Week 25 to Week 48). Demographic and clinical characteristics were recorded using a semi-structured interview, whilst outcome data were obtained using a headache diary, patient-reported outcomes, blood sampling, brain MRI, and responsiveness to intravenous infusion of CGRP. Results: The study enrolled 751 participants, with a mean age ± SD of 43.8 ± 12.2 years, of which 88.8% (n = 667) were female. At enrollment, 64.7% (n = 486) were diagnosed with chronic migraine, and 30.2% (n = 227) had history of aura. The mean monthly migraine days (MMDs) was 14.5 ± 7.0. Concomitant preventive medications were used by 48.5% (n = 364) of the participants, and 39.9% (n = 300) had failed ≥ 4 preventive medications. Conclusion: The REFORM study enrolled a population with a high migraine burden and frequent use of concomitant medications. The baseline characteristics were representative of patients with migraine in specialized headache clinics. Future publications will report the results of the investigations presented in this article. Trial registration: The study and sub-studies were registered on ClinicalTrials.gov (NCT04592952; NCT04603976; and NCT04674020). [ABSTRACT FROM AUTHOR]

The K+ and hypoxanthine (Hx) concentrations of the vitreous humour (VH) rise gradually after death, providing a means of estimating the post-mortem interval (PMI). The correlation between these analytes and the PMI is good since the vitreous chamber is partially isolated from autolytic events occurring elsewhere; the [K +] and [Hx] recorded is thus the result of changes within the eye. The present work provides a systematic review, following PRISMA recommendations, of 36 articles (3 reviews and 33 retrospective cohort studies) discussing the many procedures and regression models that have been developed for improving PMI estimates involving VH analytes. The results of a descriptive study are also provided, highlighting the causes and distribution of mortality as registered in medico-legal autopsies performed in 2019 in Galicia (northwestern Spain), and revealing the use of these PMI estimation methods in real forensic practice. Great heterogeneity was detected in the collection of VH samples, the treatments to which they were subjected before examination, and in their conservation and analysis. A lack of reproducibility in the analytical methods employed to estimate [K +] and [Hx] was noted, as well as an absence of external validation for most of the regression formulae used to determine the PMI from analyte values. The use of methods based on high-performance liquid chromatography, focal electrophoresis, or thermogravimetric/chemometric procedures might solve the problems encountered with traditional analytical techniques, offering reliable results more quickly and effectively (even when samples are contaminated). This study recommends using flexible multiple regression models that combine physical and chemical variables, and that population databases be constructed so that models can be properly validated. [ABSTRACT FROM AUTHOR]

The presence of mutated genes strongly correlates with the incidence of cancer. Decades of research, however, has not yielded any specific causative gene or set of genes for the vast majority of cancers. The Cancer Genome Atlas program was supposed to provide clarity, but it only gave much more data without any accompanying insight into how the disease begins and progresses. It may be time to notice that epidemiological studies consistently show that the environment, not genes, has the principal role in causing cancer. Since carcinogenic chemicals in our food, drink, air, and water are the primary culprits, we need to look at the biochemistry of cancer, with a focus on enzymes that invariably facilitate transformations in a cell. In particular, attention should be paid to the rate-limiting enzyme in DNA synthesis, ribonucleotide reductase (RnR), whose activity is tightly linked to tumor growth. Besides circumstantial evidence that cancer is induced at this enzyme's vulnerable free-radical-containing active site by various carcinogens, its role in initiating retinoblastoma and human papillomavirus (HPV)-related cervical cancers has been well documented in recent years. Blocking the activity of malignant RnR is a certain way to arrest cancer. [ABSTRACT FROM AUTHOR]

Background: Garcinia kola (Gluttiferae) is recommended traditionally for the management of diabetes in Nigeria. This present study evaluated the effect of the ethanol extract of G. kola seeds on the biochemical and hematological status of alloxan-induced diabetic rats. Methods: Rats were divided into six groups of five rats each. Diabetes was induced in groups 2–6 by intraperitoneal injection of alloxan monohydrate (130 mg/kg bwt.). Group 1 served as normal control, group 2 was left untreated, group 3 was treated with 2.5 mg/kg bwt. glibenclamide (standard drug), and groups 4–6 were given an oral administration of 100, 300, and 500 mg/kg body weights of extract for 21 days. Fasting blood samples were collected at baseline, day 0, 7, 14, and 21 for blood glucose evaluation. Biochemical and hematological parameters were also investigated at the end of treatment. Results: The extract produced the best effects at 500 mg/kg bwt. Blood glucose concentration was significantly (p < 0.05) reduced from days 7 to 21. A reduction from 390.50 ± 28.21 in diabetic rats to 60.50 ± 2.96 mg/dl was observed on day 21. The extract also lowered the total cholesterol (TC), triacylglycerol (TAG), low-density lipoprotein (LDL), and malondialdehyde (MDA) concentrations from 259.64 ± 52.22, 74.41 ± 15.39, 162.81 ± 48.44, and 57.75 ± 2.06 mg/dl to 120.32 ± 24.25, 41.05 ± 0.00, 82.31 ± 20.26, and 37.25 ± 2.21 mg/dl respectively. Superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) activities were significantly increased from 31.25 ± 12.50, 33.59 ± 5.94, and 0.50 ± 0.01 IU/L to 68.75 ± 12.50, 81.52 ± 4.16, and 1.07 ± 0.15 IU/L respectively. Red blood cell (RBC) count was restored from 192.50 ± 28.72 to 271.25 ± 47.32 (× 109). At 100 mg/kg bwt., white blood cell (WBC) count was also normalized from 8000.00 ± 2648.26 to 12800.00 ± 365.14 (× 10 mm3). Conclusion: G. Kola seeds possess antidiabetic activity and capability of restoring aberrated biochemical and hematological indices in diabetic rats. This research therefore consolidates its traditional use for the management of diabetes mellitus. [ABSTRACT FROM AUTHOR]

The aim was to test the effect of nitrate (NO3) supplementation and restriction on biomass production, synthesis of biomolecules and extracellular polymeric substances (EPS) in the microalga Ankistrodesmus fusiformis. The treatments contained BG-11 medium + different concentrations of NO3: 0.5 g (T0.5); 1.0 g (T1.0); 1.5 g (T1.5); BG-11 under NO3 limitation (TN) and control containing only BG-11 (TC). TN showed higher production of biomass (0.68 g L−1), µ (0.50 day−1) and proteins (11.16 µg mL−1). Carbohydrate content decreased with increasing NO3 concentration in the treatments. T1.5 had the highest lipid content (49.30 mg). The major fatty acids were C16:0; C18:3n3; C18:1n9c and C18:2n6c. Higher saturation was observed in treatments with lower concentrations of NO3 and TN, inverse behavior to the monounsaturated. The TN treatment showed high EPS production (30.90 mg L−1). Therefore, globally TN was the best treatment, due to its high biomass production, high EPS synthesis and relevant production of lipids and proteins, together with reduced use of nitrate. [ABSTRACT FROM AUTHOR]

According to process ontology in the philosophy of biology, the living world is better understood as processes rather than as substantial individuals. Within this perspective, an organism does not consist of a hierarchy of structures like a machine, but rather a dynamic hierarchy of processes, dynamically maintained and stabilized at different time scales. With this respect, two processual approaches on enzymes by Stein (Hyle Int J Philos Chem 10(4):5–22, 2004, Process Stud 34:62–80, 2005, Found Chem 8:3–29, 2006) and by Guttinger (Everything Flows: Towards a Processual Philosophy of Biology, Oxford University Press, Oxford, 2018) allows to think of macromolecules as relational and processual entities. In this work, I propose to extend their arguments to another case study within the biochemical domain, which is the case of ligand receptors and receptor-mediated biosignaling. The aim of this work is to analyze the case of G Protein-Coupled Receptors and biosignaling under the consideration of a processual ontology. I will defend that the processual ontology framework is adequate for the biochemical domain and that it allows accounting for the current biochemical knowledge related to the case study. [ABSTRACT FROM AUTHOR]

The discovery of bacterial compounds that have antifungal properties opens up opportunities for the development of agents that protect crops from a devastating disease.Natural products that protect plants from a common disease. [ABSTRACT FROM AUTHOR]

Malachite green (C52H54N4O12) is a synthetic dye that is used in textile industries as a colorant and in aquaculture sectors to contain microbial damage. Aquatic contamination of malachite green (MG) has been reported globally. Fish is the highest trophic organism among aquatic inhabitants, highly sensitive to waterborne contaminants (metals, coloring agents, etc.). Toxicity of waterborne chemicals on nontarget organisms can be determined by assessing biomarkers. Assessing blood parameters and tissue antioxidants (enzymatic and nonenzymatic) is useful to evaluate MG toxicity. To initiate the MG toxicity data for freshwater fish (Cyprinus carpio), the median lethal toxicity was primarily evaluated. Then, hematological, blood biochemical (glucose, protein, and cholesterol) and tissue biochemical (amino acids, lipids), and vital tissue (gills, liver, and kidney) antioxidant capacity (CAT, LPO, GST, GR, POxy, vitamin C, and GSH) of C. carpio were analyzed under acute (LC50–96 h) and sublethal (Treatment I—1/10th and Treatment II—1/5th LC50–96 h) exposure periods (28 days). Molecular docking for MG with hemoglobin was also obtained. Biomarkers examined were affected in the MG-treated groups with respect to the control group. Significant changes (p < 0.05) were observed in hematology (Hb, RBCs, and WBCs), glucose, proteins, lipids and tissue CAT, LPO, and GST activities under acute MG exposure. In sublethal treatment groups, biomarkers studied were significant (p < 0.05) throughout the study period. The potential for MG binding to hemoglobin was tested in this study. MG is potentially a multiorgan toxicant. Literally a chemical that is harmful to the aquatic environment if safety is concerned. [ABSTRACT FROM AUTHOR]