Synthesis of δ-MnO2 via ozonation routine for low temperature formaldehyde removal.

Nowadays, it is still a challenge to prepared high efficiency and low cost formaldehyde (HCHO) removal catalysts in order to tackle the long-living indoor air pollution. Herein, δ-MnO2 is successfully synthesized by a facile ozonation strategy, where Mn2+ is oxidized by ozone (O3) bubble in an alkaline solution. It presents one of the best catalytic properties with a low 100% conversion temperature of 85°C for 50 ppm of HCHO under a GHSV of 48,000 mL/(g·hr). As a comparison, more than 6 times far longer oxidation time is needed if O3 is replaced by O2. Characterizations show that ozonation process generates a different intermediate of tetragonal ß-HMnO2, which would favor the quick transformation into the final product δ-MnO2, as compared with the relatively more thermodynamically stable monoclinic γ-HMnO2 in the O2 process. Finally, HCHO is found to be decomposed into CO2 via formate, dioxymethylene and carbonate species as identified by room temperature in-situ diffuse reflectance infrared fourier transform spectroscopy. All these results show great potency of this facile ozonation routine for the highly active δ-MnO2 synthesis in order to remove the HCHO contamination.

Sextuple knockouts of a highly conserved and coexpressed AUXIN/INDOLE-3-ACETIC ACID gene set confer shade avoidance-like responses in Arabidopsis.

AUXIN/INDOLE-3-ACETIC ACIDs are transcriptional repressors for auxin signalling. Aux/IAAs of Arabidopsis thaliana display some functional redundancy. The IAA3/SHY2 clade (IAA1, IAA2, IAA3 and IAA4) show strong sequence similarity, but no higher-order mutants have been reported. Here, through CRISPR/Cas9 genome editing, we generated loss-of-function iaa1/2/3/4 mutants. The quadruple mutants only exhibited a weak phenotype. Thus, we additionally knocked out IAA7/AXR2 and IAA16, which are coexpressed with IAA1/2/3/4. Remarkably, under white light control conditions, the iaa1/2/3/4/7/16 mutants exhibited a shade avoidance-like phenotype with over-elongated hypocotyls and petioles and hyponastic leaves. The sextuple mutants were highly sensitive to low light intensity, and the hypocotyl cells of the mutants were excessively elongated. Transcriptome profiling and qRT-PCR analyses revealed that the sextuple mutation upregulated IAA19/MSG2 and IAA29, two shared shade/auxin signalling targets. Besides, genes encoding cell wall-remodelling proteins and shade-responsive transcription regulators were upregulated. Using dual-luciferase reporter assays, we verified that IAA2/IAA7 targeted the promoters of cell wall-remodelling genes to inhibit their transcription. Our work indicates that the IAA1/2/3/4/7/16 gene set is required for the optimal integration of auxin and shade signalling. The mutants generated here should be valuable for exploring the complex interactions among signal sensors, transcription activators and transcription repressors during hormone/environmental responses.

Deciphering the TCF19/miR-199a-5p/SP1/LOXL2 pathway: Implications for breast cancer metastasis and epithelial-mesenchymal transition.

Globally, breast cancer (BC) is the predominant malignancy with a significant death rate due to metastasis. The epithelial-mesenchymal transition (EMT) is a fundamental initiator for metastatic progression. Through advanced computational strategies, TCF19 was identified as a critical EMT-associated gene with diagnostic and prognostic significance in BC, based on a novel EMT score. Molecular details and the pro-EMT impact of the TCF19/miR-199a-5p/SP1/LOXL2 axis were explored in BC cell lines through in vitro validations, and the oncogenic and metastatic potential of TCF19 and LOXL2 were investigated using subcutaneous and tail-vein models. Additionally, BC-specific enrichment of TCF19 and LOXL2 was measured using a distribution landscape driven by diverse genomic analysis techniques. Molecular pathways revealed that TCF19-induced LOXL2 amplification facilitated migratory, invasive, and EMT activities of BC cells in vitro, and promoted the growth and metastatic establishment of xenografts in vivo. TCF19 decreases the expression of miR-199a-5p and alters the nuclear dynamics of SP1, modulating SP1's affinity for the LOXL2 promoter, leading to increased LOXL2 expression and more malignant characteristics in BC cells. These findings unveil a novel EMT-inducing pathway, the TCF19/miR-199a-5P/SP1/LOXL2 axis, highlighting the pivotal role of TCF19 and suggesting potential for novel therapeutic approaches for more focused BC interventions.

The Controlled Preparation of a Carrier-Free Nanoparticulate Formulation Composed of Curcumin and Piperine Using High-Gravity Technology.

Carrier-free nanoparticulate formulations are an advantageous platform for the oral administration of insoluble drugs with the expectation of improving their bioavailability. However, the key limitation of exploiting carrier-free nanoparticulate formulations is the controlled preparation of drug nanoparticles on the basis of rational prescription design. In the following study, we used curcumin (Cur) and piperine (Pip) as model water-insoluble drugs and developed a new method for the controlled preparation of carrier-free drug nanoparticles via multidrug co-assembly in a high-gravity environment. Encouraged by the controlled regulation of the nucleation and crystal growth rate of high-gravity technology accomplished by a rotating packed bed, co-amorphous Cur-Pip co-assembled multidrug nanoparticles with a uniform particle size of 130 nm were successfully prepared, exhibiting significantly enhanced dissolution performance and in vitro cytotoxicity. Moreover, the hydrogen bonding interactions between Cur and Pip in nanoparticles provide them with excellent re-dispersibility and storage stability. Moreover, the oral bioavailability of Cur was dramatically enhanced as a result of the smaller particle size of the co-assembled nanoparticles and the effective metabolic inhibitory effect of Pip. The present study provides a controlled approach to preparing a carrier-free nanoparticulate formulation through a multidrug co-assembly process in the high-gravity field to improve the oral bioavailability of insoluble drugs.

Supplementation of Methionine Dipeptide Enhances the Milking Performance of Lactating Dairy Cows.

Methionine dipeptide (Met-Met) could improve milk protein synthesis in bovine epithelia mammary cells and lactating mice, while the effects of Met-Met on lactation performance, rumen fermentation and microbiota profile in lactating dairy cows have not been explored. For this reason, 60 Chinese lactating Holstein cows were allocated into three treatment groups: control group (CON), 6 g/d methionine dipeptide group (MM), and 6.12 g/d rumen-protected methionine dipeptide group (RPMM). The experiment lasted for 10 weeks to monitor lactation performance, plasma amino acid profile and rumen fermentation parameters and microbiota profile. Results showed that MM increased the energy-corrected milk (ECM), and RPMM increased both milk yield and ECM (p < 0.05). The milk protein concentration and yield were increased by MM and RPMM (p < 0.05). The rumen fermentation showed that RPMM increased total volatile fatty acids, acetate and valerate concentrations (p < 0.05). The relative abundance of Firmicutes, including Succiniclasticum, Selenomonas and Clostridium_XlVa, were enriched and the Prevotella was decreased by RPMM (p < 0.05). In summary, daily supplementing with 6 g of MM or RPMM in lactating dairy cows could improve milk yield and both percentage and yield of milk protein, and RPMM benefited the rumen fermentation and altered the bacterial composition. These results provided the first evidence that Met-Met supplementation can improve lactation performance of dairy cows.

Material Engineering Strategies for Efficient Hydrogen Evolution Reaction Catalysts.

Water electrolysis, a key enabler of hydrogen energy production, presents significant potential as a strategy for achieving net-zero emissions. However, the widespread deployment of water electrolysis is currently limited by the high-cost and scarce noble metal electrocatalysts in hydrogen evolution reaction (HER). Given this challenge, design and synthesis of cost-effective and high-performance alternative catalysts have become a research focus, which necessitates insightful understandings of HER fundamentals and material engineering strategies. Distinct from typical reviews that concentrate only on the summary of recent catalyst materials, this review article shifts focus to material engineering strategies for developing efficient HER catalysts. In-depth analysis of key material design approaches for HER catalysts, such as doping, vacancy defect creation, phase engineering, and metal-support engineering, are illustrated along with typical research cases. A special emphasis is placed on designing noble metal-free catalysts with a brief discussion on recent advancements in electrocatalytic water-splitting technology. The article also delves into important descriptors, reliable evaluation parameters and characterization techniques, aiming to link the fundamental mechanisms of HER with its catalytic performance. In conclusion, it explores future trends in HER catalysts by integrating theoretical, experimental and industrial perspectives, while acknowledging the challenges that remain.

Dihydroartemisinin-driven selective anti-lung cancer proliferation by binding to EGFR and inhibition of NRAS signaling pathway-induced DNA damage.

Chemotherapeutic agents can inhibit the proliferation of malignant cells due to their cytotoxicity, which is limited by collateral damage. Dihydroartemisinin (DHA), has a selective anti-cancer effect, whose target and mechanism remain uncovered. The present work aims to examine the selective inhibitory effect of DHA as well as the mechanisms involved. The findings revealed that the Lewis cell line (LLC) and A549 cell line (A549) had an extremely rapid proliferation rate compared with the 16HBE cell line (16HBE). LLC and A549 showed an increased expression of NRAS compared with 16HBE. Interestingly, DHA was found to inhibit the proliferation and facilitate the apoptosis of LLC and A549 with significant anti-cancer efficacy and down-regulation of NRAS. Results from molecular docking and cellular thermal shift assay revealed that DHA could bind to epidermal growth factor receptor (EGFR) molecules, attenuating the EGF binding and thus driving the suppressive effect. LLC and A549 also exhibited obvious DNA damage in response to DHA. Further results demonstrated that over-expression of NRAS abated DHA-induced blockage of NRAS. Moreover, not only the DNA damage was impaired, but the proliferation of lung cancer cells was also revitalized while NRAS was over-expression. Taken together, DHA could induce selective anti-lung cancer efficacy through binding to EGFR and thereby abolishing the NRAS signaling pathway, thus leading to DNA damage, which provides a novel theoretical basis for phytomedicine molecular therapy of malignant tumors.

Dihydroartemisinin-driven TOM70 inhibition leads to mitochondrial destabilization to induce pyroptosis against lung cancer.

Enhancement of malignant cell immunogenicity to relieve immunosuppression of lung cancer microenvironment is essential in lung cancer treatment. In previous study, we have demonstrated that dihydroartemisinin (DHA), a kind of phytopharmaceutical, is effective in inhibiting lung cancer cells and boosting their immunogenicity, while the initial target of DHA's intracellular action is poorly understood. The present in-depth analysis aims to reveal the influence of DHA on the highly expressed TOM70 in the mitochondrial membrane of lung cancer. The affinity of DHA and TOM70 was analyzed by microscale thermophoresis (MST), pronase stability, and thermal stability. The functions and underlying mechanism were investigated using western blots, qRT-PCR, flow cytometry, and rescue experiments. TOM70 inhibition resulted in mtDNA damage and translocation to the cytoplasm from mitochondria due to the disruption of mitochondrial homeostasis. Further ex and in vivo findings also showed that the cGAS/STING/NLRP3 signaling pathway was activated by mtDNA and thereby malignant cells underwent pyroptosis, leading to enhanced immunogenicity of lung cancer cells in the presence of DHA. Nevertheless, DHA-induced mtDNA translocation and cGAS/STING/NLRP3 mobilization were synchronously attenuated when TOM70 was replenished. Finally, DHA was demonstrated to possess potent anti-lung cancer efficacy in vitro and in vivo. Taken together, these data confirm that TOM70 is an important target for DHA to disturb mitochondria homeostasis, which further activates STING and arouses pyroptosis to strengthen immunogenicity against lung cancer thereupon. The present study provides vital clues for phytomedicine-mediated anti-tumor therapy.

Joint association of TyG index and high sensitivity C-reactive protein with cardiovascular disease: a national cohort study.

BACKGROUND: Both the triglyceride-glucose (TyG) index, as a surrogate marker of insulin resistance, and systemic inflammation are predictors of cardiovascular diseases; however, little is known about the coexposures and relative contributions of TyG index and inflammation to cardiovascular diseases. Using the nationally representative data from the China Health and Retirement Longitudinal Study (CHARLS), we conducted longitudinal analyses to evaluate the joint and mutual associations of the TyG index and high-sensitivity C-reactive protein (hsCRP) with cardiovascular events in middle-aged and older Chinese population. METHODS: This study comprised 8 658 participants aged at least 45 years from the CHARLS 2011 who are free of cardiovascular diseases at baseline. The TyG index was calculated as Ln [fasting triglyceride (mg/dL) × fasting glucose (mg/dL)/2]. Cardiovascular events were defined as the presence of physician-diagnosed heart disease and/or stroke followed until 2018.We performed adjusted Cox proportional hazards regression and mediation analyses. RESULTS: The mean age of the participants was 58.6 ± 9.0 years, and 3988 (46.1%) were females. During a maximum follow-up of 7.0 years, 2606 (30.1%) people developed cardiovascular diseases, including 2012 (23.2%) cases of heart diseases and 848 (9.8%) cases of stroke. Compared with people with a lower TyG index (< 8.6 [median level]) and hsCRP < 1 mg/L, those concurrently with a higher TyG and hsCRP had the highest risk of overall cardiovascular disease (adjusted hazard ratio [aHR], 1.300; 95% CI 1.155-1.462), coronary heart disease (aHR, 1.294; 95% CI 1.130-1.481) and stroke (aHR, 1.333; 95% CI 1.093-1.628), which were predominant among those aged 70 years or below. High hsCRP significantly mediated 13.4% of the association between the TyG index and cardiovascular disease, while TyG simultaneously mediated 7.9% of the association between hsCRP and cardiovascular risk. CONCLUSIONS: The findings highlight the coexposure effects and mutual mediation between the TyG index and hsCRP on cardiovascular diseases. Joint assessments of the TyG index and hsCRP should be underlined for the residual risk stratification and primary prevention of cardiovascular diseases, especially for middle-aged adults.

Comparison of triglyceride glucose index and modified triglyceride glucose indices in prediction of cardiovascular diseases in middle aged and older Chinese adults.

BACKGROUND: Triglyceride and glucose (TyG) index, a surrogate marker of insulin resistance, has been validated as a predictor of cardiovascular disease. However, effects of TyG-related indices combined with obesity markers on cardiovascular diseases remained unknown. We aimed to investigate the associations between TyG index and modified TyG indices with new-onset cardiovascular disease and the time-dependent predictive capacity using a national representative cohort. METHODS: This study is a retrospective observational cohort study using data from China Health and Retirement Longitudinal Study (CHARLS) of 7 115 participants. The TyG index was calculated as Ln [fasting triglyceride (mg/dL) × fasting glucose (mg/dL)/2]. The modified TyG indices were developed combining TyG with body mass index (BMI), waist circumference (WC) and waist-to-height ratio (WHtR). We used adjusted Cox proportional hazards regression to analyze the association and predictive capacity based on hazard ratio (HR) and Harrell's C-index. RESULTS: Over a 7-year follow-up period, 2136 participants developed cardiovascular disease, including 1633 cases of coronary heart disease and 719 cases of stroke. Compared with the lowest tertile group, the adjusted HR (95% CI) for new-onset cardiovascular disease in the highest tertile for TyG, TyG-BMI, TyG-WC, and TyG-WHtR were 1.215 (1.088-1.356), 1.073 (0.967-1.191), 1.078 (0.970-1.198), and 1.112 (1.002-1.235), respectively. The C-indices of TyG index for cardiovascular disease onset were higher than other modified TyG indices. Similar results were observed for coronary heart disease and stroke. CONCLUSION: TyG and TyG-WhtR were significantly associated with new-onset cardiovascular diseases, and TyG outperformed the modified TyG indices to identify individuals at risk of incident cardiovascular event.

Anti-lung cancer synergy of low-dose doxorubicin and PD-L1 blocker co-delivered via mild photothermia-responsive black phosphorus.

We have previously identified a latent interaction mechanism between non-small cell lung cancer cells (NSCLCC) and their associated macrophages (TAM) mediated by mutual paracrine activation of the HMGB1/RAGE/NF-κB signaling. Activation of this mechanism results in TAM stimulation and PD-L1 upregulation in the NSCLCC. In the present work, we found that free DOX at a low concentration that does not cause DNA damage could activate the HMGB1/RAGE/NF-κB/PD-L1 pathway byinducing oxidative stress. It was thus proposed that a combination of low-dose DOX and a PD-L1 blocker delivered in the NSCLC tumor would achieve synergistic TAM stimulation and thereby synergetic anti-tumor potency. To prove this idea, DOX and BMS-202 (a PD-L1 blocker) were loaded to black phosphorus (BP) nanoparticles after dosage titration to yield the BMS-202/DOX@BP composites that rapidly disintegrated and released drug cargo upon mild photothermal heating at 40 °C. In vitro experiments then demonstrated that low-dose DOX and BMS-202 delivered via BMS-202/DOX@BP under mild photothermia displayed enhanced tumor cell toxicity with a potent synergism only in the presence of TAM. This enhanced synergism was due to an anti-tumor M1-like TAM phenotype that was synergistically induced by low dose DOX plus BMS-202 only in the presence of the tumor cells, indicating the damaged tumor cells to be the cardinal contributor to the M1-like TAM stimulation. In vivo, BMS-202/DOX@BP under mild photothermia exhibited targeted delivery to NSCLC graft tumors in mice and synergistic anti-tumor efficacy of delivered DOX and BMS-202. In conclusion, low-dose DOX in combination with a PD-L1 blocker is an effective strategy to turn TAM against their host tumor cells exploiting the HMGB1/RAGE/NF-κB/PD-L1 pathway. The synergetic actions involved highlight the value of TAM and the significance of modulating tumor cell-TAM cross-talk in tumor therapy. Photothermia-responsive BP provides an efficient platform to translate this strategy into targeted, efficacious tumor therapy.

Ultrahigh-reflective optical thin films prepared by reactive magnetron sputtering with RF-induced substrate bias.

Optical thin films with high-reflectivity (HR) are essential for applications in quantum precision measurements. In this work, we propose a coating technique based on reactive magnetron sputtering with RF-induced substrate bias to fabricate HR-optical thin films. First, atomically flat SiO2 and Ta2O5 layers have been demonstrated due to the assistance of radio-frequency plasma during the coating process. Second, a distributed Bragg reflector (DBR) mirror with an HR of ∼99.999 328% centered at 1397 nm has been realized. The DBR structure is air-H{LH}19-substrate, in which the L and H denote a single layer of SiO2 with a thickness of 237.8 nm and a single layer of Ta2O5 with a thickness of 171.6 nm, respectively. This novel coating method would facilitate the development of HR reflectors and promote their wide applications in precision measurements.

Comparison of the efficacy between the dual therapy of tegoprazan and the quadruple therapy of tegoprazan: A randomized, controlled, multicenter study.

INTRODUCTION: Tegoprazan (TPZ), a potassium-competitive acid blocker, exerts a strong acid-suppression effect and a rapid onset of action. However, research on TPZ-amoxicillin (TA) dual treatment is limited. Here, we compared the safety and efficacy of TPZ-amoxicillin dual treatment and TPZ, bismuth potassium citrate, amoxicillin, and clarithromycin (TBAC) quadruple therapy in patients newly diagnosed with H. pylori infection over a 14-day treatment period. METHODS: A total of 236 patients newly diagnosed with H. pylori were enrolled in this multi-center, prospective, open-label, and randomized controlled study. Patients randomly received either TA dual or TBAC quadruple therapy. The incidence of adverse reactions and treatment compliance were recorded and then analyzed. RESULTS: The intention-to-treat analysis revealed that H. pylori-eradication rates were 83.9% (95% confidence interval [CI] 78.2%-91.3%) and 81.4% (95% CI 74.2%-88.5%) for the TA and TBAC groups, respectively, with no statistically significant difference between them (P = 0.606). The per-protocol analysis revealed that the H. pylori-eradication rates were 88.3% and 84.8% for the TA and TBAC groups, respectively (P = 0.447). The incidence of adverse reactions was significantly lower in the TA group than in the TBAC group (4.2% vs. 15.3%, P = 0.004). Moreover, the TA group demonstrated substantially higher treatment compliance than the TBAC group (94.1% vs. 89.0%, P = 0.020). CONCLUSION: The TA dual therapy successfully eradicated H. pylori with a high eradication rate and a low incidence of adverse reactions. Therefore, this treatment is recommended as an alternative course for patients newly diagnosed with H. pylori infection.

Effect of inflammatory response on joint function after hip fracture in elderly patients: A clinical study.

BACKGROUND: Excellent hip joint function facilitates limb recovery and improves the quality of survival. This study aimed to investigate the potential risk factors affecting postoperative joint functional activity and outcomes in elderly hip fractures patients and to provide evidence for patient rehabilitation and clinical management. AIM: To explore the relationship between inflammatory factors and hip function and the interaction between inflammation and health after hip fracture in elderly patients. METHODS: The elderly patients who had hip fracture surgery at our hospital between January 1, 2021, and December 31, 2022 were chosen for this retrospective clinical investigation. Patients with excellent and fair postoperative hip function had their clinical information and characteristics gathered and compared. Age, gender, fracture site, surgical technique, laboratory indices, and other variables that could have an impact on postoperative joint function were all included in a univariate study. To further identify independent risk factors affecting postoperative joint function in hip fractures, risk factors that showed statistical significance in the univariate analysis were then included in a multiple logistic regression analysis. In addition to this, we also compared other outcome variables such as visual analogue scale and length of hospital stay between the two groups. RESULTS: A total of 119 elderly patients with hip fractures were included in this study, of whom 37 were male and 82 were female. The results of univariate logistic regression analysis after excluding the interaction of various factors showed that there was a statistically significant difference in interleukin (IL)-6, IL-8, IL-10, C-reactive protein (CRP), and complement C1q (C1q) between the fair and excellent joint function groups (P < 0.05). The results of multiple logistic regression analysis showed that IL-6 > 20 pg/mL [(Odds ratio (OR) 3.070, 95%CI: 1.243-7.579], IL-8 > 21.4 pg/ mL (OR 3.827, 95%CI: 1.498-9.773), CRP > 10 mg/L (OR 2.142, 95%CI: 1.020-4.498) and C1q > 233 mg/L (OR 2.339, 95%CI: 1.094-5.004) were independent risk factors for poor joint function after hip fracture surgery (all P < 0.05). CONCLUSION: After hip fractures in older patients, inflammatory variables are risk factors for fair joint function; therefore, early intervention to address these markers is essential to enhance joint function and avoid consequences.

Serum cystatin C and stroke risk: a national cohort and Mendelian randomization study.

Purpose: The debate over the causal and longitudinal association between cystatin C and stroke in older adults persists. Our aim was to assess the link between cystatin C levels, both measured and genetically predicted, and stroke risk. Methods: This study employed a retrospective cohort design using samples of the China Health and Retirement Longitudinal Study (CHARLS), which is a nationally representative cohort recruiting individuals aged 45 years or above. A multivariate logistic model and the two-sample Mendelian randomization framework were used to investigate the longitudinal and genetically predicted effect of serum cystatin C on stroke. Results: The study population had a mean age of 59.6 (SD ±9.5), with 2,996 (46.1%) women. After adjusting for confounding factors, compared to those in the first quartile of cystatin C, those in the last quartile had the greatest risk of stroke incidence [odds ratio (OR), 1.380; 95% confidence interval (CI), 1.046-1.825]. The Mendelian randomization analysis showed that a genetically predicted cystatin C level was positively associated with total stroke (OR by inverse variance-weighted method, 1.114; 95% CI, 1.041-1.192). Conclusions: This national cohort study suggests that higher serum cystatin C is associated with an increased risk of total stroke, which is further supported by Mendelian randomization.

The synergistic antibacterial activity and mechanism of colistin-oxethazaine combination against gram-negative pathogens.

Background: The rapid spread of bacteria with plasmid-mediated resistance to antibiotics poses a serious threat to public health. The search for potential compounds that can increase the antibacterial activity of existing antibiotics is a promising strategy for addressing this issue. Methods: Synergistic activity of the FDA-approved agent oxethazine combined with colistin was investigated in vitro using checkerboard assays and time-kill curves. The synergistic mechanisms of their combination of oxethazine and colistin was explored by fluorescent dye, scanning electron microscopy (SEM) and LC-MS/MS. The synergistic efficacy was evaluated in vivo by the Galleria mellonella and mouse sepsis models. Results: In this study, we found that oxethazine could effectively enhance the antibacterial activity of colistin against both mcr-positive and -negative pathogens, and mechanistic assays revealed that oxethazine could improve the ability of colistin to destruct bacterial outer membrane and cytoplasmic membrane permeability. In addition, their combination triggered the accumulation of reactive oxygen species causing additional damage to the membrane structure resulting in cell death. Furthermore, oxethazine significantly enhanced the therapeutic efficacy of colistin in two animal models. Conclusion: These results suggested that oxethazine, as a promising antibiotic adjuvant, can effectively enhance colistin activity, providing a potential strategy for treating multidrug-resistant bacteria.