Lactic acid bacteria reduce bacterial diarrhea in rabbits via enhancing immune function and restoring intestinal microbiota homeostasis.

BACKGROUND: Numerous previous reports have demonstrated the efficacy of Lactic acid bacteria (LAB) in promoting growth and preventing disease in animals. In this study, Enterococcus faecium ZJUIDS-R1 and Ligilactobaciiius animalis ZJUIDS-R2 were isolated from the feces of healthy rabbits, and both strains showed good probiotic properties in vitro. Two strains (108CFU/ml/kg/day) were fed to weaned rabbits for 21 days, after which specific bacterial infection was induced to investigate the effects of the strains on bacterial diarrhea in the rabbits. RESULTS: Our data showed that Enterococcus faecium ZJUIDS-R1 and Ligilactobaciiius animalis ZJUIDS-R2 interventions reduced the incidence of diarrhea and systemic inflammatory response, alleviated intestinal damage and increased antibody levels in animals. In addition, Enterococcus faecium ZJUIDS-R1 restored the flora abundance of Ruminococcaceae1. Ligilactobaciiius animalis ZJUIDS-R2 up-regulated the flora abundance of Adlercreutzia and Candidatus Saccharimonas. Both down-regulated the flora abundance of Shuttleworthia and Barnesiella to restore intestinal flora balance, thereby increasing intestinal short-chain fatty acid content. CONCLUSIONS: These findings suggest that Enterococcus faecium ZJUIDS-R1 and Ligilactobaciiius animalis ZJUIDS-R2 were able to improve intestinal immunity, produce organic acids and regulate the balance of intestinal flora to enhance disease resistance and alleviate diarrhea-related diseases in weanling rabbits.

Spontaneous regression of a giant uterine leiomyoma after delivery: a case report and literature review.

BACKGROUND: Uterine leiomyomas are hormone-dependent benign tumors and often begin to shrink after menopause due to the reduction in ovarian steroids. The influence of pregnancy on uterine leiomyomas size remains unclear. Here, we present a case of spontaneous regression of a giant uterine leiomyoma after delivery. CASE PRESENTATION: A 40-year-old woman presented with multiple uterine leiomyomas, one of which is a giant uterine leiomyomas (approximately 8 cm in diameter) that gradually shrinked after delivery. At over two months postpartum, the large myometrial leiomyoma had transformed into a submucosal leiomyoma, and over 3 years postpartum, both the submucosal leiomyoma and multiple intramural leiomyomas completely regressed. CONCLUSION: Spontaneous regression of a giant uterine leiomyom is rare after delivery. Considering uterine leiomyoma regression until over 3 year postpartum,we need to observe the regression of uterine fibroid for a longer time postpartum in the absence of fibroid related complications. In addition, it will provide new insights for treatment options of uterine leiomyomas in the future.

The effect of outdoor activities on the medical expenditure of older people: multiple chain mediating effects of health benefits.

BACKGROUND: With the global aging population, attention to the health and medical issues of older adults is increasing. By analyzing the relationship between older people's participation in outdoor activities and medical expenditure, this study aims to provide a scientific basis for improving their quality of life and reducing the medical burden. METHODS: Data on outdoor activity participation, medical expenditures, and relevant variables were collected through questionnaires and databases. A multi-chain mediation effect model was established to analyze the impact of outdoor activities on the medical expenditure of older people, considering mediation effects and heterogeneity. RESULTS: Results revealed that increased participation in outdoor activities among older adults correlated with lower medical expenditures. Outdoor activities positively influenced their health by improving mental health, cognition, eating habits, and activities of daily living, resulting in reduced medical expenditures. Robustness tests confirmed the consistent effect of outdoor activities on older people's medical expenditure. CONCLUSION: These findings contribute to understanding the relationship between outdoor activities, health, and medical expenditure in older people, guiding policy formulation and interventions. Encouraging and supporting older adults in outdoor activities can enhance their quality of life and alleviate medical resource strain. The study's conclusions can also inform health promotion measures for other populations and serve as a basis for future research in this area.

Covalent Immobilization of Natural Biomolecules on Chitin Nanocrystals.

As a highly crystalline and renewable natural polymer nanomaterial, chitin nanocrystals (ChNCs) have attracted intense interest in the biomedical field. The structure of a ChNC is composed of an acetylglucosamine unit containing two hydroxyl groups and an acetyl group. The acetyl group can be converted to the active amino group through deacetylation, which is under the condition of maintaining the rod-like morphology and high crystalline property and is beneficial for the following modification and potential application. We investigated the relationship between different treatments and varied crystallinities of the modified ChNC, which obtained surface amino groups and aldehyde groups and retained high crystallinity. The natural biomolecules were covalently immobilized on the surface of the ChNC. The etherification was performed based on the hydroxyl groups. Based on the amino groups and the aldehyde groups, the carboxyamine and Knoevenagel condensation reactions were realized on ChNCs. Finally, natural biomolecule-modified ChNCs showed no or low cytotoxicity, antibacterial properties, and high antioxidant properties, which extended their potential biomedical applications.

Peptidase inhibitor (PI16) impairs bladder cancer metastasis by inhibiting NF-κB activation via disrupting multiple-site ubiquitination of NEMO.

BACKGROUND: Bladder cancer (BLCA) is a malignancy that frequently metastasizes and leads to poor patient prognosis. It is essential to understand the molecular mechanisms underlying the progression and metastasis of BLCA and identify potential biomarkers. METHODS: The expression of peptidase inhibitor 16 (PI16) was analysed using quantitative PCR, immunoblotting and immunohistochemistry assays. The functional roles of PI16 were evaluated using wound healing, transwell, and human umbilical vein endothelial cell tube formation assays, as well as in vivo tumour models. The effects of PI16 on nuclear factor κB (NF-κB) signalling activation were examined using luciferase reporter gene systems, immunoblotting and immunofluorescence assays. Co-immunoprecipitation was used to investigate the interaction of PI16 with annexin-A1 (ANXA1) and NEMO. RESULTS: PI16 expression was downregulated in bladder cancer tissues, and lower PI16 levels correlated with disease progression and poor survival in patients with BLCA. Overexpressing PI16 inhibited BLCA cell growth, motility, invasion and angiogenesis in vitro and in vivo, while silencing PI16 had the opposite effects. Mechanistically, PI16 inhibited the activation of the NF-κB pathway by interacting with ANXA1, which inhibited K63 and M1 ubiquitination of NEMO. CONCLUSIONS: These results indicate that PI16 functions as a tumour suppressor in BLCA by inhibiting tumour growth and metastasis. Additionally, PI16 may serve as a potential biomarker for metastatic BLCA.

Ascomylactam C Induces an Immunogenic Cell Death Signature via Mitochondria-Associated ER Stress in Lung Cancer and Melanoma.

Ascomylactam C (AsC) is a new 13-membered-ring macrocyclic alkaloid, which was first isolated and identified in 2019 from the secondary metabolites of the mangrove endophytic fungus Didymella sp. CYSK-4 in the South China Sea. AsC has been found to have a broad-spectrum cytotoxic activity. However, the antitumor effects in vivo and mechanisms of AsC remain unclear. The aim of this study was to describe the effects of AsC on lung cancer and melanoma cells and to explore the antitumor molecular mechanism of AsC. In vitro, we used plate colony formation experiments and demonstrated the ability of AsC to inhibit low-density tumor growth. An Annexin V/PI cell apoptosis detection experiment revealed that AsC induced tumor cell apoptosis. In vivo, AsC suppressed the tumor growth of LLC and B16F10 allograft significantly in mice, and promoted the infiltration of CD4+ T and CD8+ T cells in tumor tissues. Mechanistically, by analyses of Western blotting, immunofluorescence and ELISA analysis, we found that AsC increased ROS formation, induced endoplasmic reticulum (ER) stress, activated the protein kinase RNA-like ER kinase (PERK)/eukaryotic translation initiation factor (eIF2α)/activating transcription factor 4 (ATF4)/C/EBP homologous protein (CHOP) signaling pathway, and induced immunogenic cell death (ICD) of tumor cells. Our results suggest that AsC may be a potentially promising antitumor drug candidate.

A Meroterpenoid from Tibetan Medicine Induces Lung Cancer Cells Apoptosis through ROS-Mediated Inactivation of the AKT Pathway.

As a traditional Tibetan medicine in China, Meconopsis grandis Prain has been used to treat a variety of illnesses by local people for thousands of years. However, the active ingredients contained in Meconopsis grandis Prain and its pharmacodynamic mechanisms have scarcely been reported. We isolated a meroterpenoid named D1399 from Meconopsis grandis Prain endophytic fungi with strong antitumor activity. The structure analysis showed that D1399 is an alkaloid containing a 13-membered macrocyclic structure. The IC50 of D1399 for human lung cancer cells' viability ranged from 0.88 to 2.45 µM. Furthermore, we utilized TUNEL assay and western blotting to investigate the antitumor effectiveness of D1399. The results have shown that D1399 induced the apoptosis of lung cancer cells on the extrinsic and intrinsic pathways by boosting ROS generation and repressing AKT activity. In the mouse xenograft model, the average tumor weight with 30 mg·kg-1 D1399 treatment exhibited 73.19% inhibition compared with the untreated control, without affecting body weight loss. Above all, for the first time, our study provides a possible mechanism for the antitumor activity of D1399 in vitro and in vivo as a natural product from Tibetan medicine with Meconopsis grandis Prain, which may be a potentially promising antitumor drug candidate.

Dapoxetine, a Selective Serotonin Reuptake Inhibitor, Suppresses Zika Virus Infection In Vitro.

Zika virus (ZIKV) belongs to the Flavivirus genus of the Flaviviridae family, and is a pathogen posing a significant threat to human health. Currently, there is a lack of internationally approved antiviral drugs for the treatment of ZIKV infection, and symptomatic management remains the primary clinical approach. Consequently, the exploration of safe and effective anti-ZIKV drugs has emerged as a paramount imperative in ZIKV control efforts. In this study, we performed a screening of a compound library consisting of 1789 FDA-approved drugs to identify potential agents with anti-ZIKV activity. We have identified dapoxetine, an orally administered selective serotonin reuptake inhibitor (SSRI) commonly employed for the clinical management of premature ejaculation (PE), as a potential inhibitor of ZIKV RNA-dependent RNA polymerase (RdRp). Consequently, we conducted surface plasmon resonance (SPR) analysis to validate the specific binding of dapoxetine to ZIKV RdRp, and further evaluated its inhibitory effect on ZIKV RdRp synthesis using the ZIKV Gluc reporter gene assay. Furthermore, we substantiated the efficacy of dapoxetine in suppressing intracellular replication of ZIKV, thereby demonstrating a concentration-dependent antiviral effect (EC50 values ranging from 4.20 µM to 12.6 µM) and negligible cytotoxicity (CC50 > 50 µM) across diverse cell lines. Moreover, cell fluorescence staining and Western blotting assays revealed that dapoxetine effectively reduced the expression of ZIKV proteins. Collectively, our findings suggest that dapoxetine exhibits anti-ZIKV effects by inhibiting ZIKV RdRp activity, positioning it as a potential candidate for clinical therapeutic intervention against ZIKV infection.

Dispersibility Characterization of Cellulose Nanocrystals in Polymeric-Based Composites.

Cellulose nanocrystals (CNCs) are hydrophilic nanoparticles extracted from biomass with properties and functions different from cellulose and are being developed for property-oriented applications such as high stiffness, abundant active groups, and biocompatibility. It has broad application prospects in the field of composite materials, while the dispersibility of the CNC in polymers is the key to its application performance. Many reviews have discussed in-depth the modification strategies to improve the dispersibility of the CNC and summarized all characterization for the CNC, but there are no reviews on the in-depth exploration of dispersion characterization. This review is a comprehensive summary of the characterization of CNC dispersion in the matrix in terms of direct observation, indirect evaluation, and quantified evaluation, summarizing how and why different characterization tools reveal dispersibility. In addition, "decision tree" flowcharts are presented to provide the reader with a reference for selecting the appropriate characterization method for a specific composite.

Ultrasensitive Pressure-Induced Optical Materials: Europium-Doped Hafnium Silicates with a Khibinskite Structure for Optical Pressure Sensors and WLEDs.

Ultrasensitive pressure-induced optical materials are of great importance owing to their potential applications in optical pressure sensors. However, the lack of outstanding pressure sensitivity, observable color evolution, and structure reliability limits their further development in both practical applications and luminescence theory. To overcome the above problems, an enlightening methodology is proposed to explore the high sensitivity and phase stability of hafnium silicate K2HfSi2O7 (KHSO) phosphor with a Khibinskite structure. By employing X-ray diffraction (XRD) Rietveld refinement, cryogenic spectroscopy, and ancillary calculations, information on Eu2+ ion occupation is completely obtained at atmospheric pressure. The remarkable pressure sensitivity (dλ/dP = 3.25 nm/GPa-1) and excellent phase stability up to 20 GPa, along with the reproducible color hue variation, exhibit unprecedented superiority when used in optical pressure sensors. These advantages can be assigned to the pressure-induced Eu2+-selective occupation and the unique properties of 5d-4f transition (Stokes shift, nephelauxetic effect, and intense crystal field strength), which are clearly proved by measuring the XRD patterns, Raman spectra, and Gaussian fitting spectra under compression and decompression processes. The excellent luminescence property manifests that KHSO/Eu2+ can be considered as a potential luminescent material for solid-state lighting and optical pressure sensors.

Azaphilone derivatives with anti-inflammatory activity from the mangrove endophytic fungus Penicillium sclerotiorum ZJHJJ-18.

Nine undescribed azaphilone derivatives, sclerazaphilones A-H (1-9), and three known analogues (10-12), were obtained and identified from the fermented rice cultures of a mangrove endophytic fungus Penicillium sclerotiorum ZJHJJ-18. 1D and 2D NMR, HRESIMS and spectral data indicated the chemical structures of 1-9, and their absolute configurations were assigned by experimental and computational analyses of electronic circular dichroism (ECD) spectra, and application of the chemical transformations. Compounds 1-4 were the first reported N-containing azaphilone derivatives with 5/6 dicyclic core. The bioassay results showed that compounds 3-5 exhibited effective inhibitory effects on the nitric oxide (NO) production in lipopolysaccharide (LPS)-induced RAW264.7 macrophage cells with IC50 values in the range of 6.30-9.45 µM. Moreover, a molecular docking study was conducted to investigate the probable binding interaction of 3-5 with inducible nitric oxide synthase (iNOS).

A Pair of Chromone Epimers and an Acetophenone Glucoside from the Mangrove Endophytic Fungus Mycosphaerella sp. L3A1.

Three new compounds, including a pair of chromone derivatives (1-2), and an acetophenone glucoside (3), together with three known compounds (4-6), were isolated from the mangrove endophytic fungus Mycosphaerella sp. L3A1. Their structures were elucidated by HR-ESI-MS analysis and extensive spectroscopic data. The absolute configurations of new compounds were determined using single-crystal X-ray diffraction analysis, electronic circular dichroism (ECD) calculations and chemical hydrolysis. In bioassays, compound 4 showed moderate cytotoxic activity against MDA-MB-435, HCT116, and SNB19 with IC50 values in the range of 18.5-26.29 µM.

Selective acceleration of 2-hydroxyl pyridine mono-oxygenation using specially acclimated biomass.

Biodegradation of pyridine starts with two mono-oxygenation reactions, and 2-hydroxyl pyridine (2-HP) accumulates as pyridine is mono-oxygenated in the first reaction. The accumulation of 2-HP inhibits both initial reactions. Therefore, selective acceleration of the second mono-oxygenation reaction should significantly enhance pyridine transformation and mineralization. Activated-sludge biomass was separately acclimated with pyridine or 2-HP to produce pyridine- and 2-HP-acclimated biomasses. The pyridine-acclimated biomass was superior for pyridine biodegradation, but the 2-HP-acclimated biomass was superior for 2-HP biodegradation. As a consequence, the pyridine-acclimated biomass by itself achieved faster mono-oxygenation of pyridine to 2-HP, but 2-HP accumulated, which limited mineralization to 60%. In contrast, mineralization reached 90% when one-third of the pyridine-acclimated was replaced with 2-HP-acclimated biomass, because 2-HP did not accumulate during pyridine biodegradation. The lack of 2-HP accumulation relieved its inhibition: e.g., the pyridine removal rates, normalized to the mass of pyridine-acclimated biomass, increased from 0.52 to 0.57 mM0.5⋅h-1 when one-third of the pyridine-acclimated biomass was replaced by 2-HP-acclimated biomass. Phylogenetic analysis showed that microbiological communities of pyridine-acclimated biomass and 2-HP-acclimated biomass differed in important ways. On the one hand, the 2-HP-acclimated biomass was richer and dominated by a rare biosphere, or genera having <0.1% of total reads. On the other hand, the most-enriched genus in the pyridine-acclimated community (Methylibium) is associated with the first mono-oxygenation of pyridine, while enriched genera in the 2-HP-acclimated community (Sediminibacterium and Dokdonella) are associated with the second mono-oxygenation of pyridine.

Prognostic Effect of Thoracic Sarcopaenia on Short- and Long-Term Clinical Outcomes in Patients Who Underwent Cardiac Valve Surgery.

BACKGROUND: As the proportion of elderly patients increases, higher incidence of malnutrition is found among patients with valvular heart disease. Sarcopaenia is one of the main manifestations of malnutrition. Studies have shown the certain predictive effect of sarcopaenia on the clinical outcome in different cases. This study aims to clarify the impact of computed tomography (CT)-derived thoracic sarcopaenia on clinical outcomes of patients who underwent cardiac valve surgery. METHODS: The clinical data of 216 patients who underwent cardiac valve surgery from December 2015 to June 2020 were retrospectively collected. Skeletal muscle mass at 12th thoracic vertebra level was measured to diagnose thoracic sarcopaenia. Postoperative complications and follow-up data were collected. Medium follow-up was 3.2 years. RESULTS: The prevalence of thoracic sarcopaenia was 16.7% in this study. The incidence of total complications and in-hospital mortality were higher in thoracic sarcopaenia group (p=0.024 and p=0.014, respectively). Multivariate analysis revealed that thoracic sarcopaenia is a significant predictor for postoperative complications (OR 2.319; 95% CI 1.003-5.366; p=0.049). Decreased long-term survival was observed in patients with thoracic sarcopaenia. Thoracic sarcopaenia (HR 4.178; 95% CI 2.062-8.465; p<0.001) was determined to be an independent risk factor for late mortality. CONCLUSION: Thoracic sarcopaenia defined by chest CT was independently associated with higher incidence of postoperative complications and long-term mortality. Routine preoperative evaluation of thoracic sarcopaenia deserves further consideration to enhance the predictive performance for operation risk.

Origin, Influence, and Countermeasures of Defects in Perovskite Solar Cells.

Defects are considered to be one of the most significant factors that compromise the power conversion efficiencies and long-term stability of perovskite solar cells. Therefore, it is urgent to have a profound understanding of their formation and influence mechanism, so as to take corresponding measures to suppress or even completely eliminate their adverse effects on device performance. Herein, the possible origins of the defects in metal halide perovskite films and their impacts on the device performance are analyzed, and then various methods to reduce defect density are introduced in detail. Starting from the internal and interfacial aspects of the metal halide perovskite films, several ways to improve device performance and long-term stability including additive engineering, surface passivation, and other physical treatments (annealing engineering), etc., are further elaborated. Finally, the further understanding of defects and the development trend of passivation strategies are prospected.

How bioaugmentation with Comamonas testosteroni accelerates pyridine mono-oxygenation and mineralization.

Pyridine is a common heterocycle found in industrial wastewaters. Its biodegradation begins with a mono-oxygenation reaction, and bioaugmentation with bacteria able to carry out this mono-oxygenation is one strategy to improve pyridine removal and mineralization. Although bioaugmentation has been used to enhance the biodegradation of recalcitrant organic compounds, the specific role played by the bioaugmented bacteria usually has not been addressed. We acclimated activated-sludge biomass for pyridine biodegradation and then isolated a strain -- Comamonas testosteroni -- based on its ability to biodegrade and grow on pyridine alone. Pyridine was removed faster by C. testosteroni, compared to pyridine-acclimated biomass, but pyridine mineralization was slower. Pyridine biodegradation and mineralization rates were accelerated when C. testosteroni was bioaugmented into the acclimated biomass, which increased the amount of C. testosteroni, but otherwise had minimal effects on the microbial community. The key role of C. testosteroni was to accelerate the first step of pyridine biodegradation, mono-oxygenation to 2-hydroxylpyridine (2HP), and the acclimated biomass was better able to complete downstream reactions leading to mineralization. Thus, bioaugmentation increased the rates of pyridine mono-oxygenation and subsequent mineralization through the synergistic roles of C. testosteroni and the main community in the acclimated biomass.

Characteristics of denitrification in a vertical baffled bioreactor.

A vertical baffled bioreactor (VBBR) was employed for tertiary denitrification. Its features were designed to minimize the demand for externally supplied electron donor by minimizing net biomass synthesis and oxygen respiration. Over a two-year period, complete denitrification was realized routinely in the VBBR. The nitrate-removal rate was proportion to the influent COD/N ratio, with complete denitrification possible for COD/N ratios >3 gCOD/gN. Batch kinetic tests carried out at the end of years 1 and 2 documented that supplied electron donor was oxidized in the first 1-2 h, but nitrate and nitrite reductions occurred predominantly after 2 h and were driven by internally stored electron donor. Measurements confirmed that the VBBR minimized the demand of added electron donor: The observed yield was only 0.05 mgVSS/mgCOD, and the COD demand for O2 respiration was only 1-6.7% of the COD demand for N reductions. Biofilm samples taken from the upper and lower ports in cylinder of VBBR had similarly high alpha diversity and dominant genera, but the upper biofilm had a denitrification rate about 70% greater than the lower biofilm. The higher denitrification rate in the upper biofilm correlated its higher content of active biomass.

Efficacy and safety of interleukin-17 inhibitors in the treatment of chronic rheumatic diseases: A combined and updated meta-analysis.

WHAT IS KNOWN AND OBJECTIVE: To assess the efficacy and safety of interleukin-17 inhibitors (ixekizumab, secukinumab, bimekizumab, netakimab and brodalumab) in chronic inflammatory rheumatic diseases, including ankylosing spondylitis (AS) and psoriatic arthritis (PsA). METHODS: A comprehensive search for randomized controlled trials (RCTs) evaluating efficacy and safety of interleukin-17 inhibitors was performed through PubMed, Embase and Cochrane Library databases. Quality assessment was performed using the Cochrane Collaboration risk of bias tool. Data were pooled using the fixed or random-effects models. RESULTS AND DISCUSSION: Twenty RCTs were identified: of these 9 studies on patients with AS and 11 studies on patients with PsA. Concerning clinical efficacy, a pooled analysis showed interleukin-17 inhibitors had a higher response rate for the primary endpoint (p < 0.05) and secondary endpoint (p < 0.05) at the treatment endpoint for AS/PsA patients. Moreover, an increased risk of treatment-emergent adverse events and infection was found in AS patients (p < 0.05). In contrast, no increased risk of any adverse events was reported in PsA patients. WHAT IS NEW AND CONCLUSION: In this meta-analysis, our findings found interleukin-17 inhibitors had a significant clinical benefit in the management of AS/PsA patients.

Effects of Vaccine-Related Conspiracy Theories on Chinese Young Adults' Perceptions of the HPV Vaccine: An Experimental Study.

This online experiment used the Theory of Planned Behavior to examine the impact of exposure to conspiracy social media messages on Chinese young adults' perceptions of the HPV vaccine. Three major findings were identified. First, exposure to anti-vaccine conspiracy theories resulted in less favorable attitudes toward the HPV vaccine, less positive perceived norms regarding getting vaccinated, and weaker vaccination intentions. Second, people who were more knowledgeable about the HPV vaccine had more favorable attitudes, more positive norms, higher perceived behavioral control, and greater behavioral intentions. Finally, vaccine knowledge moderated the effect of exposure to anti-vaccine conspiracy theories. Our results suggest that, among Chinese young adult social media users, preexisting knowledge of the HPV vaccine may have a protective effect against exposure to online conspiracy theories.

Synergy of strains that accelerate biodegradation of pyridine and quinoline.

Three bacterial strains were isolated from activated sludge acclimated to biodegrade pyridine and quinoline simultaneously. The strains were identified as Bacillus tropicus, Bacillus aquimaris, and Rhodococcus ruber. When the isolated bacteria were used for pyridine and quinoline biodegradation in separate or combined modes, R. ruber had much faster kinetics, and combining R. ruber with one or both of the Bacillus strains increased further the biodegradation kinetics. For example, the time needed for complete biodegradation of 1 mM quinoline and pyridine decreased to 20 h and 6 h, respectively, with the three strains combined, compared to 26 h and 7 h with R. ruber alone. Whereas quinoline was completely mineralized by all three strains, 10-14% of the pyridine persisted as a dead-end product, 2-hydroxypyridine (2HP). The acclimated sludge from which the three bacterial species were isolated was able to transform 2HP, and adding the bacterial strains (especially R. ruber) to the acclimated sludge accelerated the rate of 2HP removal and mineralization through a form of synergy.