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Enterovirus 71 (EV71) is one of the major pathogens causing hand, foot, and mouth disease in children under 5 years old, which can result in severe neurological complications and even death. Due to limited treatments for EV71 infection, the identification of novel host factors and elucidation of mechanisms involved will help to counter this viral infection. N-terminal acetyltransferase 6 (NAT6) was identified as an essential host factor for EV71 infection with genome-wide CRISPR/Cas9 screening. NAT6 facilitates EV71 viral replication depending on its acetyltransferase activity but has little effect on viral release. In addition, NAT6 is also required for Echovirus 7 and coxsackievirus B5 infection, suggesting it might be a pan-enterovirus host factor. We further demonstrated that NAT6 is required for Golgi integrity and viral replication organelle (RO) biogenesis. NAT6 knockout significantly inhibited phosphatidylinositol 4-kinase IIIß (PI4KB) expression and PI4P production, both of which are key host factors for enterovirus infection and RO biogenesis. Further mechanism studies confirmed that NAT6 formed a complex with its substrate actin and one of the PI4KB recruiters-acyl-coenzyme A binding domain containing 3 (ACBD3). Through modulating actin dynamics, NAT6 maintained the integrity of the Golgi and the stability of ACBD3, thereby enhancing EV71 infection. Collectively, these results uncovered a novel mechanism of N-acetyltransferase supporting EV71 infection.IMPORTANCEEnterovirus 71 (EV71) is an important pathogen for children under the age of five, and currently, no effective treatment is available. Elucidating the mechanism of novel host factors supporting viral infection will reveal potential antiviral targets and aid antiviral development. Here, we demonstrated that a novel N-acetyltransferase, NAT6, is an essential host factor for EV71 replication. NAT6 could promote viral replication organelle (RO) formation to enhance viral replication. The formation of enterovirus ROs requires numerous host factors, including acyl-coenzyme A binding domain containing 3 (ACBD3) and phosphatidylinositol 4-kinase IIIß (PI4KB). NAT6 could stabilize the PI4KB recruiter, ACBD3, by inhibiting the autophagy degradation pathway. This study provides a fresh insight into the relationship between N-acetyltransferase and viral infection.
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Enterovirus Humano A , Infecciones por Enterovirus , Acetiltransferasas N-Terminal , Fosfotransferasas (Aceptor de Grupo Alcohol) , Niño , Preescolar , Humanos , 1-Fosfatidilinositol 4-Quinasa/metabolismo , Actinas/metabolismo , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Antivirales , Coenzima A/metabolismo , Infecciones por Coxsackievirus , Enterovirus Humano A/fisiología , Infecciones por Enterovirus/metabolismo , Infecciones por Enterovirus/virología , Proteínas de la Membrana/metabolismo , Acetiltransferasas N-Terminal/metabolismo , Biogénesis de Organelos , Fosfotransferasas (Aceptor de Grupo Alcohol)/metabolismo , Replicación Viral/fisiologíaRESUMEN
Microplastic pollution, an emerging pollution issue, has become a significant environmental concern globally due to its ubiquitous, persistent, complex, toxic, and ever-increasing nature. As a multifaceted and diverse suite of small plastic particles with different physicochemical properties and associated matters such as absorbed chemicals and microbes, future research on microplastics will need to comprehensively consider their multidimensional attributes. Here, we introduce a novel, conceptual framework of the "microplastome", defined as the entirety of various plastic particles (<5 mm), and their associated matters such as chemicals and microbes, found within a sample and its overall environmental and toxicological impacts. As a novel concept, this paper aims to emphasize and call for a collective quantification and characterization of microplastics and for a more holistic understanding regarding the differences, connections, and effects of microplastics in different biotic and abiotic ecosystem compartments. Deriving from this lens, we present our insights and prospective trajectories for characterization, risk assessment, and source apportionment of microplastics. We hope this new paradigm can guide and propel microplastic research toward a more holistic era and contribute to an informed strategy for combating this globally important environmental pollution issue.
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Microplásticos , Contaminantes Químicos del Agua , Plásticos/toxicidad , Ecosistema , Estudios Prospectivos , Monitoreo del Ambiente , Contaminantes Químicos del Agua/toxicidadRESUMEN
Copolymerization provides an effective approach to tune the photophysical properties of non-conventional luminescent polymers (NCLPs). In this study, the controlling of intrinsic emissions of polyacrylonitrile (PAN) copolymers is revealed by a delicate difference of secondary monomers. The introduction of methacrylate comonomers can induce a 70-nm red-shifting in the PL emission of copolymers compared with that of acrylate-containing copolymers. The mechanism of such "copolymerization induced red-shifting" in PAN copolymers is investigated. It is demonstrated that the presence of the α-methyl group in the copolymers can enhance the chain rigidity and through-space conjugation (TSC) of C≡N groups, resulting in the red-shifting of emission.
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Acrilonitrilo , Luminiscencia , Polímeros , Metacrilatos , PolimerizacionRESUMEN
As MPs are released into the soil, various equilibrium statuses are expected. MPs could play roles as a "source," a "cleaner," or a "sink" of HOCs. Three types of MPs (LDPE, PLA, and PS) were selected to study their effect on polychlorinated biphenyl (PCBs) relative bioavailability (RBA) measured by a mouse model. As a "source" of HOCs, exposure to MP-sorbed PCBs resulted in their accumulation in adipose tissue with PCB RBA as 101 ± 6.73% for LDPE, 76.2 ± 19.2% for PLA, and 9.22 ± 2.02% for PS. The addition of 10% MPs in PCB-contaminated soil led to a significant (p < 0.05) reduction in PCB RBA (52.2 ± 16.7%, 49.3 ± 4.85%, and 47.1 ± 5.99% for LDPE, PLA, and PS) compared to control (75.0 ± 4.26%), implying MPs acted as "cleaner" by adsorbing PCBs from the digestive system and reducing PCB accumulation. MPs acted as a "sink" for PCBs in contaminated soil after aging, but the sink effect varied among MP types with more pronounced effect for LDPE than PLA and PS. Therefore, the role played by MPs in bioavailability of HOCs closely depended on the MP types as well as the equilibrium status among MPs, soil, and HOCs.
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Microplásticos , Bifenilos Policlorados , Animales , Ratones , Disponibilidad Biológica , Plásticos , Polietileno , PoliésteresRESUMEN
Large amounts of microplastics (MPs) enter the soil along with the amendment of sludge to soil. However, it is still unclear about the response of MPs occurrence and the adsorption behaviors of cadmium (Cd)on MPs to typical agricultural environmental scenarios. In present work, three kinds of MPs (polyethylene, polypropylene, and polystyrene) were chosen to investigate that response in three agricultural environmental scenarios with sludge-amended soil, including dry-wet alteration (7 d, five cycles), microbial addition (Bacillus subtilis, 0.05 g/g soil), and Ultraviolet (UV) irradiation (340 nm, 4 × 15 W, 4 d). The results showed that there was the highest adsorption capacity of Cd on MPs (36.21, 45.15, 12.43 µg/g for PE, PP, PS, respectively) after UV irradiation exceeding those from MPs triggered by other two scenarios). UV irradiation caused an increase in the abundance of Streptomyces, an expansion in specific surface area, a significant change in surface morphologies, an improvement in crystallinity or the formation of new crystals, and an enhancement in C-O and CO content, and then resulted in the incremental adsorption capacity of Cd on MPs. The findings are important of significance for controlling the environmental risks from sludge MPs via carrying heavy metals in the soil-plant systems.
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Microplásticos , Contaminantes del Suelo , Plásticos , Cadmio , Suelo , Aguas del Alcantarillado , Contaminantes del Suelo/análisisRESUMEN
The complicated contamination of microplastics (MPs) and heavy metals in sludge has garnered substantial attention in recent years; however, research on the behavior of MPs loading of heavy metals in sludge after sludge treatment methods is limited. Four representative sludge treatment methods were selected herein: anaerobic digestion, thermal drying, thermal hydrolysis (TH), and aerobic composting. Before and after sludge treatment, the chemical bonding of MPs, cadmium (Cd) adsorption properties, and metabolic changes in the microbial community succession was analyzed, and the factors influencing differences in Cd sorption by sludge MPs were explored. The results revealed that Cd adsorption by MPs occurs as multilayer physical adsorption that can be well fitted by Freundlich isotherms. Compared with the other three treatments, TH led to the most significant effect on the chemical bonding properties of the MPs, with a more than two-fold increase in C-O single bonds and CO double bonds, as well as adsorption of the highest amount of Cd at 767 µg/g. In addition, sludge conductivity and water content also affected Cd sorption capacity, with correlation coefficients of 0.405 and -0.384. Pedobacter, Flavobacterium, Lysobacter, and Sphingobacterium in the sludge presented a high degree of coupling with adsorption capacity, it was inferred that the above dominant species of bacteria may affect the adsorption of Cd by microplastics through the production of extracellular enzyme forms.
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Metales Pesados , Contaminantes Químicos del Agua , Adsorción , Cadmio/química , Microplásticos , Plásticos/química , Aguas del Alcantarillado , Agua , Contaminantes Químicos del Agua/análisisRESUMEN
This study explored a bidirectional impact on the recognition accuracy of various facial expressions deriving from both the observer and sender in a sample of Chinese participants. A facial manipulation task was used to examine the ability of an observer's facial feedback to modulate the recognition of various facial expressions. Furthermore, the effect of a sender's facial expression with an open or closed mouth on recognition accuracy was investigated. The results showed that only recognition accuracy of a sad facial expression was influenced simultaneously by bidirectional sources from a sender and observer. Moreover, the impact of the unidirectional cue of a sender's facial feature (i.e., mouth openness) on happy and neutral faces was found to influence the recognition accuracy of these faces, but not the observer's bodily state. These findings indicate that the bidirectional impact derived from an observer and sender on facial expression recognition accuracy differs for emotional and neutral expressions.
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Emociones/fisiología , Expresión Facial , Adolescente , Adulto , Femenino , Humanos , Masculino , Adulto JovenRESUMEN
In this study, cobalt etched graphite felt electrodes were produced using a simple etching technique. It was used in combination with a solid polymer electrolyte (SPE) for the degradation of the target contaminant Orange II by Electro-Fenton (EF) technique in low conductivity water. In this method, 94% of Orange II in low conductivity water was removed in 90 min. The characterization analysis substantiates the hypothesis that the electrodes produced exhibit a three-dimensional porous structure, augmented defect concentration, and enhanced electron transfer capability. In addition, the potential reaction mechanism was inferred from the radical quenching experiments, and hydroxyl radicals (·OH) were deemed the main reactive substances. The combination of cobalt etched graphite felt electrodes with SPE demonstrates remarkable efficacy in the treatment of organic wastewater characterized by low electrical conductivity.
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Compuestos Azo , Bencenosulfonatos , Grafito , Contaminantes Químicos del Agua , Grafito/química , Cobalto , Polímeros , Electrodos , Agua , Contaminantes Químicos del Agua/química , Peróxido de Hidrógeno/química , Oxidación-ReducciónRESUMEN
Bone implantation is one of the recognized and effective means of treating bone defects, but osteoporosis and bone tumor-related bone abnormalities have a series of problems such as susceptibility to infection, difficulty in healing, and poor therapeutic effect, which poses a great challenge to clinical medicine. Three-dimensional things may be printed using 3D printing. Researchers can feed materials through the printer layer by layer to create the desired shape for a 3D structure. It is widely employed in the healing of bone defects, and it is an improved form of additive manufacturing technology with prospective future applications. This review's objective is to provide an overview of the findings reports pertaining to 3D printing biopolymers in recent years, provide an overview of biopolymer materials and their composites with black phosphorus for 3D printing bone implants, and the characterization methods of composite materials are also summarized. In addition, summarizes 3D printing methods based on ink printing and laser printing, pointing out their special features and advantages, and provide a combination strategy of photothermal therapy and bone regeneration materials for black phosphorus-based materials. Finally, the associations between bone implant materials and immune cells, the bio-environment, as well as the 3D printing bone implants prospects are outlined.
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Fósforo , Impresión Tridimensional , Andamios del Tejido , Humanos , Biopolímeros/química , Andamios del Tejido/química , Fósforo/química , Animales , Regeneración Ósea , Materiales Biocompatibles/química , Prótesis e Implantes , Huesos , Ingeniería de Tejidos/métodos , Sustitutos de Huesos/química , Sustitutos de Huesos/uso terapéuticoRESUMEN
Formaldehyde adhesive is the primary source of indoor formaldehyde pollution, posing a serious threat to human health. Soybean meal (SM), as an abundant biomacromolecule and co-product of soybean oil industry, emerges as a promising alternative to formaldehyde adhesive. However, the SM adhesive exhibits inferior water resistance and unsatisfactory bonding strength. In this study, a novel core-sheath structure with an inexpensive pulp cellulose core and a hyperbranched polymer sheath is synthesized and introduced into SM to develop a robust bio-based adhesive. Specifically, aldehyde-functionalized pulp cellulose is grafted with hyperbranched polyamide, which is terminated via epoxy groups, to synthesize a core-sheath hybrid (APC@HBPA-EP). The core-sheath APC@HBPA-EP serves as both a crosslinker and an enhancer. The results show that the wet shear strength of the modified SM adhesive exhibits a remarkable 520 % increase to 0.93 MPa, and its dry shear strength reaches 2.10 MPa, meeting the established indoor use standards. The Young's modulus of the modified SM adhesive shows a significant 282 % increase to 19.27 GPa. Additionally, the modified SM adhesive exhibited superior impact toughness (7.48 KJ/m2), which increased by 24 times compared with pure SM adhesive. This study provides a versatile strategy for developing robust protein adhesives, hydrogel patch, and composite coatings.
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Celulosa , Glycine max , Humanos , Adhesivos/química , Polímeros , FormaldehídoRESUMEN
BACKGROUND: Increasing evidence has shown that environmental factors play a crucial role in the pathogenesis of periodontitis. Humans are simultaneously exposed to a variety of environmental brominated flame retardants (BFRs). However, the relationship between BFRs in periodontitis remains unclear. This study aimed to investigate the overall association between BFRs and periodontitis in a nationally representative US population and to further identify important chemicals. METHODS: Data from 3322 NHANES participants from 2009 to 2016 were used. Serum BFRs were registered, including PBDE-28, PBDE-47, PBDE-85, PBDE-99, PBDE100, PBDE-153, PBDE-154, PBDE-183, PBDE-209 and PBB-153. Survey weighted generalized logistic regression models, restricted cubic splines (RCS) were conducted to assess single BFRs exposure with periodontitis. Meanwhile, weighted quantile sum (WQS) regression and Bayesian kernel machine regression (BKMR) were used to evaluate the overall association of BFRs mixtures with periodontitis and to identify significant chemicals. RESULTS: A total of 3322 participants were included in the study, of whom 1795 had periodontitis. After adjusting for potential confounders, multiple logistic regression analysis revealed significant positive associations between serum levels of PBDE-28, PBDE-47, PBDE-85, PBDE-99, PBDE-100, PBDE-154, PBDE-183, and PBB-153 and the risk of periodontitis (all P < 0.05). A dose-response relationship was observed for many of these BFRs, with higher quantiles associated with an increased risk of periodontitis. WQS regression identified PBDE-183 (38.60%), PBDE-153 (21.20%), PBDE-209 (14.40%), and PBDE-99 (11.90%) as the BFRs with the largest weights contributing to the overall mixture effect on periodontitis risk. BKMR analysis further supported the positive association between serum BFRs and periodontitis, with most individual BFRs showing a positive trend, except for PBDE-153. Restricted cubic spline analysis revealed a generally increasing probability of periodontitis with increasing concentrations of BFRs, albeit with some nonlinear patterns for certain compounds. CONCLUSION: In conclusion, this study provides compelling evidence of a significant association between exposure to brominated flame retardants (BFRs) and an increased risk of periodontitis in a nationally representative sample of U.S. adults. Elevated serum levels of several BFRs, including PBDE-28, PBDE-47, PBDE-85, PBDE-99, PBDE-100, PBDE-154, PBDE-183, and PBB-153, were found to be positively associated with periodontitis, exhibiting a dose-response relationship.
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Exposición a Riesgos Ambientales , Retardadores de Llama , Éteres Difenilos Halogenados , Periodontitis , Retardadores de Llama/análisis , Humanos , Adulto , Femenino , Éteres Difenilos Halogenados/sangre , Periodontitis/epidemiología , Periodontitis/inducido químicamente , Periodontitis/sangre , Masculino , Persona de Mediana Edad , Estados Unidos/epidemiología , Exposición a Riesgos Ambientales/estadística & datos numéricos , Contaminantes Ambientales/sangre , Anciano , Teorema de Bayes , Adulto JovenRESUMEN
Nowadays, medical polyurethanes with favorable and durable antibacterial properties received more attention, because of avoiding repeated replacement of interventional materials and reducing patients' pain. In this thesis, non-soluble antibacterial polyurethane (NAPU) based on cation antibacterial mechanism was prepared by photo-grafting chitosan azide and heparin azide into polyurethane (PU). -NH3+of chitosan azide absorbed bacteria, inhibiting and breaking their mobility and structures. Heparin azide prevented cations from penetrating bacteria's membranes and inhibited their growth. The results showed that chitosan azide and heparin azide were successfully grafted into PU. The highest antibacterial rate was 92.07%, cytotoxicity grade ranging from 0-1 (RGR standard) and water contact angle exhibiting 60°, attributing to cation antibacterial effect and -OH existing. Tensile strength was up to 23.91 MPa and was suitable for using as medical materials. NAPU with long-lasting coating both possessed antibacterial properties and persistence, which can solve the problem of medical catheters' long-term using.
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Antibacterianos , Azidas , Cationes , Quitosano , Heparina , Poliuretanos , Poliuretanos/química , Quitosano/química , Antibacterianos/farmacología , Antibacterianos/química , Heparina/química , Azidas/química , Ensayo de Materiales , Resistencia a la Tracción , Escherichia coli/efectos de los fármacos , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Animales , Humanos , Pruebas de Sensibilidad Microbiana , Staphylococcus aureus/efectos de los fármacos , Ratones , SolubilidadRESUMEN
The prevalence of infertility caused by endometrial defects is steadily increasing, posing a significant challenge to women's reproductive health. In this study, injectable "homing-like" bioactive decellularized extracellular matrix short-fibers (DEFs) of porcine skin origin are innovatively designed for endometrial and fertility restoration. The DEFs can effectively bind to endometrial cells through noncovalent dipole interactions and release bioactive growth factors in situ. In vitro, the DEFs effectively attracted endometrial cells through the "homing-like" effect, enabling cell adhesion, spreading, and proliferation on their surface. Furthermore, the DEFs effectively facilitated the proliferation and angiogenesis of human primary endometrial stromal cells (HESCs) and human umbilical vein endothelial cells (HUVECs), and inhibited fibrosis of pretreated HESCs. In vivo, the DEFs significantly accelerated endometrial restoration, angiogenesis, and receptivity. Notably, the deposition of endometrial collagen decreased from 41.19 ± 2.16% to 14.15 ± 1.70% with DEFs treatment. Most importantly, in endometrium-injured rats, the use of DEFs increased the live birth rate from 30% to an impressive 90%, and the number and development of live births close to normal rats. The injectable "homing-like" bioactive DEFs system can achieve efficient live births and intrauterine injection of DEFs provides a new promising clinical strategy for endometrial factor infertility.
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Endometrio , Nacimiento Vivo , Femenino , Animales , Ratas , Porcinos , Humanos , Modelos Animales de Enfermedad , Embarazo , Matriz Extracelular Descelularizada , Ratas Sprague-Dawley , Células Endoteliales de la Vena Umbilical HumanaRESUMEN
Corneal damage contributes to blindness in millions of people. Simulating natural corneas with artificial corneas is challenging due to material and manufacturing limitations, including poor mechanical properties, complex manufacturing processes, and ocular histocompatibility. In this study, electrospun micro-nanofibrous decellularized extracellular matrix (dECM) is combined with digital light processing 3D bioprinting and validated as a bioartificial cornea for the first time. Electrospinning gives the material a controllable shape, and the electrospun micro-nanofibrous dECM, with preserved inherent biochemical components, can better mimic the natural ECM native microenvironment. An efficient platform can be developed for creating novel structural materials, when combined with intelligent manufacturing. Artificial biological corneas developed using this method showed five-fold improvements in mechanical properties (248.5 ± 35.67 kPa vs. 56.91 ± 3.68 kPa,p< 0.001), superior guidance for cell organization and adhesion, and better maintenance of the cellular phenotype of keratocytes. In animal studies,in vivotransplantation of this artificial cornea showed better regeneration, which accelerated corneal epithelialization and maintained corneal transparency. This method has potential for biomedical applications, and bioartificial corneas manufactured by this method have ideal properties as an alternative to lamellar keratoplasty, with promise for clinical transformation.
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Bioimpresión , Nanofibras , Animales , Humanos , Matriz Extracelular Descelularizada , Bioimpresión/métodos , Córnea , Matriz Extracelular/química , Andamios del Tejido/química , Ingeniería de Tejidos/métodosRESUMEN
BACKGROUND: Hand, foot and mouth disease (HFMD) is a common illness in young children. It also can be seen in adults occasionally. Enterovirus 71 (EV71), a pathogen that causes not only HFMD but also neurological complications and even death, has caused many HFMD outbreaks in China. However, till now the data about the duration of EV71 shedding is very limited. RESULTS: A total of 136 throat swabs and fecal samples were collected from 27 children and 3 adults, which includs 7 close contacts, 9 mild cases and 14 severe cases,. The participants were divided into three groups namely, severe case group, mild case group and close contact group. All the samples were assayed with real-time polymerase chain reaction (PCR). Kruskal-Wallis Test was employed to compare the difference in duration of viral RNA shedding among three groups. The results showed that significant difference in duration of EV71 shedding was found among three groups (P < 0.01). The longest duration of EV71 shedding in fecal samples is 54 days and 30 days in throat swabs. CONCLUSIONS: HFMD is characterized by extended excretion of EV71. Our results suggest that the duration of EV71 shedding is correlated with the severity of the disease. EV71 shedding through feces can persist more than 54 days. Prolonged virus shedding is a potential risk factor of proliferating HFMD epidemic.
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Enterovirus Humano A/aislamiento & purificación , Enfermedad de Boca, Mano y Pie/virología , Esparcimiento de Virus , Adulto , Preescolar , China , Heces/virología , Femenino , Enfermedad de Boca, Mano y Pie/patología , Humanos , Lactante , Masculino , Factores de TiempoRESUMEN
Polyetheretherketone (PEEK) is being increasingly recognized as a highly promising polymer implant in orthopaedics due to its advantageous biocompatibility, favorable processability, and radiation resistance. Nonetheless, the long-term application of PEEK implants in vivo faces challenges due to unfavorable post-implantation inflammatory and immune reactions, which result in suboptimal osseointegration rates. Hence, biofunctionalizing the surface of PEEK implants emerges as a viable strategy to enhance osseointegration and increase the success rate. In this study, we developed a multifunctional PEEK implant through the in-situ incorporation of chitosan-coated bioactive glass nanoparticles (BGNs). This approach can impart immunomodulatory properties and enhance the potential for osseointegration. The resulting biofunctionalized PEEK material exhibited multiple beneficial effects. For instance, it facilitated M2 phenotypic polarization of macrophages, diminished the expression of inflammatory factors, and enhanced the osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) in vitro. Moreover, it exhibited an improved capacity for osseointegration when tested in vivo. The findings of the experiment highlighted the pivotal and complex role of the biofunctionalized PEEK implant in maintaining typical bone immunity and metabolism. The study proposes that the application of chitosan-BGNs presents a straightforward approach to developing multifunctional implants with the ability to promote biomineralization and immunomodulation, specifically tailored for orthopaedic applications.
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Quitosano , Magnesio , Osteogénesis , Regeneración Ósea , Polietilenglicoles/farmacología , Diferenciación CelularRESUMEN
Nanoplastics induce transgenerational toxicity to aquatic organisms, but the specific pathways for the maternal transfer of nanoplastics remain unclear. Herein, laser scanning confocal microscopy (LSCM) observations identified the specific pathways on the maternal transfer of polystyrene (PS) nanoplastics (25 nm) in Daphnia magna. In vivo and in vitro experiments showed that PS nanoplastics could enter the brood chamber through its opening and then be internalized to eggs and embryos using LSCM imaging (pathway I). In addition, PS nanoplastics were observed in the oocytes of the ovary, demonstrating gut-ovary-oocyte transfer (pathway II). Furthermore, label-free hyperspectral imaging was used to detect the distribution of nanoplastics in the embryos and ovary of Daphnia, again confirming the maternal transfer of nanoplastics through the two pathways mentioned above. The contribution from pathway I (88%) was much higher than pathway II (12%) based on nanoflow cytometry quantification. In addition, maternal transfer in Daphnia depended on the particle size of PS nanoplastics, as demonstrated by using LSCM and hyperspectral imaging. Unlike 25 nm nanoplastics, 50 nm PS nanoplastics could enter the brood chamber and the eggs/embryos (pathway I), but were not detected in the ovary (pathway II); 100 nm PS nanoplastics were difficult to be internalized by eggs/embryos and could not enter the ovary either. These findings provide insight into the maternal transfer mechanisms of nanoplastics in Daphnia, and are critical for better understanding the transgenerational toxicity of aquatic organisms.
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Nanopartículas , Contaminantes Químicos del Agua , Animales , Femenino , Daphnia/metabolismo , Microplásticos/metabolismo , PoliestirenosRESUMEN
Species in Ectrichodiinae are known for their prey specialization on millipedes. However, knowledge of the morphological adaptations to this unique feeding habit was limited. In the current study, we examined the microstructures of the antennae, mouthparts, and legs of four millipede feeding ectrichodiines, Ectrychotes andreae (Thunberg, 1888), Haematoloecha limbata Miller, 1953, Labidocoris pectoralis (Stål, 1863), and Neozirta eidmanni (Taueber, 1930), and compared them with those of three species of tribelocephalines, a group closely related to Ectrichodiinae. On the antennae, we found four types of antennal sensilla. On the mouthparts, we recognized four types of labial sensilla. Sampled ectrichodiines have distinctly more and denser slightly transverse ridges on the external side of mandibles than tribelocephalines. E. andreae and H. limbata possess numerous small papillae fringed with densely arranged finger-print-like grains on the trochanter and femur; these probably facilitate the immobilization of prey. Overall, our study illustrates, at a microstructural level, the remarkable morphological adaption of prey manipulation in ectrichodiine, and has enhanced our understanding about stenophagy in the family Reduviidae.
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The local charge density and distribution of extracellular membranes play a crucial role in the various cellular processes, such as regulation and localization of membrane proteins, electrophysiological signal transduction, transcriptional control, cell growth, and cell death. In this study, a novel scanning ion conductance microscopy-based method is employed to extracellular membrane mapping. This method allows to not only visualize the dynamic topography and surface charge distribution around individual cells, but also distinguish the charge difference. To validate the accuracy and effectiveness of this method, the charge density on model sample surfaces are initially manipulated and the charge sensing mechanism using finite element modeling (FEM) is explored subsequently. By applying this method, both the extracellular charge distributions and topography structures of normal and senescent human dental pulp stem cells (hDPSCs) are able to monitor. Interestingly, it is observed that the surface charge became significantly more negative after cellular senescence. This innovative approach enables us to gain valuable insights into surface charge changes during cellular senescence, which can contribute to a better understanding of the underlying mechanisms and potential therapeutic strategies for age-related diseases.
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Biodegradable plastics (BDP) are increasingly applied; however, there has been of concerns about their environmental safety, especially from nondegradable additive compositions. Until now, data of ecotoxicity of BDP additives is scarce. Here, nematode C. elegans was used to comparatively evaluate toxicity of an isocyanate additive, i.e., Hexamethylene diisocyanate (HDI), a maleic anhydride, i.e., Diallyl maleate (DIM), and other four BDP organic additives. These additives caused lethality of nematodes at µg L-1 level, of lowest LC50 value of HDI/DIM. Uniform exposure to these additives resulted in various degrees of inhibitions in body volumes and longevity, indicating developmental toxicity. Moreover, BDP additives induced significant elevations of gst-4 expression, especially mean 123.54 %/234.29 % increase in HDI/DIM group, but reduced ges-1 expression, which indicates oxidative damages and mitochondrial dysfunction. BDP additives further caused inhibition in locomotor and food intake/excretion behavior, and related damages of glutamatergic neurons and GABAergic neurons, indicating their neurotoxicity. We found HDI and DIM presented relatively strong effects on susceptible endpoints including lethality, gst-4, mean lifespan, food intake and excretion behavior. Overall, this study suggests prominent ecotoxic risk of isocyanates and maleic anhydrides as BDP additives, which is significant for the selection of environmentally friendly BDP additives.