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2.
Water Res ; 251: 121089, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38277823

RESUMO

We piloted the incorporation of side-stream enhanced biological phosphorus removal (S2EBPR) with A/B stage short-cut nitrogen removal processes to enable simultaneous carbon-energy-efficient nutrients removal. This unique configuration and system conditions exerted selective force on microbial populations distinct from those in conventional EBPR. Interestingly, effective P removal was achieved with the predominance of Acinetobacter (21.5 ± 0.1 %) with nearly negligible level of known conical PAOs (Ca. Accumulibacter and Tetrasphaera were 0.04 ± 0.10 % and 0.47 ± 0.32 %, respectively). Using a combination of techniques, such as fluorescence in situ hybridization (FISH) coupled with single cell Raman spectroscopy (SCRS), the metabolic tracing of Acinetobacter-like cells exerted PAO-like phenotypic profiling. In addition, comparative metagenomics analysis of the closely related Acinetobacter spp. revealed the EBPR relevant metabolic pathways. Further oligotyping analysis of 16s rRNA V4 region revealed sub-clusters (microdiversity) of the Acinetobacter and revealed that the sub-group (oligo type 1, identical (100 % alignment identity) hits from Acinetobacter_midas_s_49494, and Acinetobacter_midas_s_55652) correlated with EBPR activities parameters, provided strong evidence that the identified Acinetobacter most likely contributed to the overall P removal in our A/B-shortcut N-S2EBPR system. To the best of our knowledge, this is the first study to confirm the in situ EBPR activity of Acinetobacter using combined genomics and SCRS Raman techniques. Further research is needed to identify the specific taxon, and phenotype of the Acinetobacter that are responsible for the P-removal.


Assuntos
Fósforo , Rios , Fósforo/metabolismo , RNA Ribossômico 16S/genética , Hibridização in Situ Fluorescente , Reatores Biológicos , Polifosfatos/metabolismo , Esgotos
3.
Water Res ; 251: 121050, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38241807

RESUMO

While the adsorption/bio-oxidation (A/B) process has been widely studied for carbon capture and shortcut nitrogen (N) removal, its integration with enhanced biological phosphorus (P) removal (EBPR) has been considered challenging and thus unexplored. Here, full-scale pilot testing with an integrated system combining A-stage high-rate activated sludge with B-stage partial (de)nitrification/anammox and side-stream EBPR (HRAS-P(D)N/A-S2EBPR) was conducted treating real municipal wastewater. The results demonstrated that, despite the relatively low influent carbon load, the B-stage P(D)N-S2EBPR system could achieve effective P removal performance, with the carbon supplement and redirection of the A-stage sludge fermentate to the S2EBPR. The novel process configuration design enabled a system shift in carbon flux and distribution for efficient EBPR, and provided unique selective factors for ecological niche partitioning among different key functionally relevant microorganisms including polyphosphate accumulating organisms (PAOs) and glycogen-accumulating organisms (GAOs). The combined nitrite from B-stage to S2EBPR and aerobic-anoxic conditions in our HRAS-P(D)N/A-S2EBPR system promoted DPAOs for simultaneous internal carbon-driven denitrification via nitrite and P removal. 16S rRNA gene-based oligotyping analysis revealed high phylogenetic microdiversity within the Accumulibacter population and discovered coexistence of certain oligotypes of Accumulibacter and Competibacter correlated with efficient P removal. Single-cell Raman micro-spectroscopy-based phenotypic profiling showed high phenotypic microdiversity in the active PAO community and the involvement of unidentified PAOs and internal carbon-accumulating organisms that potentially played an important role in system performance. This is the first pilot study to demonstrate that the P(D)N-S2EBPR system could achieve shortcut N removal and influent carbon-independent EBPR simultaneously, and the results provided insights into the effects of incorporating S2EBPR into A/B process on metabolic activities, microbial ecology, and resulted system performance.


Assuntos
Esgotos , Purificação da Água , Desnitrificação , Fósforo/metabolismo , Rios , Nitrogênio , RNA Ribossômico 16S , Filogenia , Nitritos , Projetos Piloto , Reatores Biológicos , Purificação da Água/métodos , Polifosfatos/metabolismo , Carbono
4.
Water Res ; 245: 120540, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37688851

RESUMO

Side-stream enhanced biological phosphorus removal process (S2EBPR) has been demonstrated to improve performance stability and offers a suite of advantages compared to conventional EBPR design. Design and optimization of S2EBPR require modification of the current EBPR models that were not able to fully reflect the metabolic functions of and competition between the polyphosphate-accumulating organisms (PAOs) and glycogen-accumulating organisms (GAOs) under extended anaerobic conditions as in the S2EBPR conditions. In this study, we proposed and validated an improved model (iEBPR) for simulating PAO and GAO competition that incorporated heterogeneity and versatility in PAO sequential polymer usage, staged maintenance-decay, and glycolysis-TCA pathway shifts. The iEBPR model was first calibrated against bulk batch testing experiment data and proved to perform better than the previous EBPR model for predicting the soluble orthoP, ammonia, biomass glycogen, and PHA temporal profiles in a starvation batch testing under prolonged anaerobic conditions. We further validated the model with another independent set of anaerobic testing data that included high-resolution single-cell and specific population level intracellular polymer measurements acquired with single-cell Raman micro-spectroscopy technique. The model accurately predicted the temporal changes in the intracellular polymers at cellular and population levels within PAOs and GAOs, and further confirmed the proposed mechanism of sequential polymer utilization, and polymer availability-dependent and staged maintenance-decay in PAOs. These results indicate that under extended anaerobic phases as in S2EBPR, the PAOs may gain competitive advantages over GAOs due to the possession of multiple intracellular polymers and the adaptive switching of the anaerobic metabolic pathways that consequently lead to the later and slower decay in PAOs than GAOs. The iEBPR model can be applied to facilitate and optimize the design and operations of S2EBPR for more reliable nutrient removal and recovery from wastewater.

5.
J Cosmet Dermatol ; 22(4): 1400-1409, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36762385

RESUMO

DESIGN: Interventional, prospective, four arm randomized control. SETTING: Outpatient department, Department of Dermatology, Venereology and Leprology, AIIMS Jodhpur (Rajasthan), India. PARTICIPANTS: Two hundred patients. METHODS: The intervention administered in the groups were normal saline (A), vitamin D3 (B), MIP (C), and MMR (D). The injections were given into the largest wart at 2-weekly intervals until complete clearance or for a maximum of seven sittings. Post-treatment clearance of the injected wart and the distant wart was compared on the basis of change in wart number, percentage clearance, and mean time to complete clearance. Side effects were recorded. RESULTS: A total of 197 patients were recruited. The mean percentage improvement in the injected and non-injected warts was 68.4% and 66.8%, respectively. Intention to treat analysis (ITT) showed that complete clearance of lesions in injected wart occurred in placebo, vit D3 , MMR, and MIP arms in 64%, 66%, 58%, and 55% patients, respectively (p > 0.05), while in the non-injected warts in 62%, 64%, 52%, and 53%, respectively (p > 0.05). The mean time to achieve complete clearance of wart was fastest in MIP at 7.1 weeks followed by MMR at 7.2 weeks, VIT D3 at 7.4 weeks and in placebo group 7.8 weeks (p > 0.05). Side effects noted were fever, pain, erythema, and swelling which was highest in VIT D3 group (p < 0.05). CONCLUSION: The efficacy of immunotherapies was comparable to placebo with minimal side effects.


Assuntos
Papiloma , Verrugas , Humanos , Colecalciferol/efeitos adversos , Vacina contra Sarampo-Caxumba-Rubéola/efeitos adversos , Estudos Prospectivos , Injeções Intralesionais , Índia , Verrugas/tratamento farmacológico , Vitamina D , Papiloma/tratamento farmacológico , Vitaminas/efeitos adversos
6.
Environ Sci Technol ; 56(18): 13473-13484, 2022 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-36048618

RESUMO

Rapid progress in various advanced analytical methods, such as single-cell technologies, enable unprecedented and deeper understanding of microbial ecology beyond the resolution of conventional approaches. A major application challenge exists in the determination of sufficient sample size without sufficient prior knowledge of the community complexity and, the need to balance between statistical power and limited time or resources. This hinders the desired standardization and wider application of these technologies. Here, we proposed, tested and validated a computational sampling size assessment protocol taking advantage of a metric, named kernel divergence. This metric has two advantages: First, it directly compares data set-wise distributional differences with no requirements on human intervention or prior knowledge-based preclassification. Second, minimal assumptions in distribution and sample space are made in data processing to enhance its application domain. This enables test-verified appropriate handling of data sets with both linear and nonlinear relationships. The model was then validated in a case study with Single-cell Raman Spectroscopy (SCRS) phenotyping data sets from eight different enhanced biological phosphorus removal (EBPR) activated sludge communities located across North America. The model allows the determination of sufficient sampling size for any targeted or customized information capture capacity or resolution level. Promised by its flexibility and minimal restriction of input data types, the proposed method is expected to be a standardized approach for sampling size optimization, enabling more comparable and reproducible experiments and analysis on complex environmental samples. Finally, these advantages enable the extension of the capability to other single-cell technologies or environmental applications with data sets exhibiting continuous features.


Assuntos
Produtos Biológicos , Fósforo , Humanos , Aprendizado de Máquina , Fósforo/química , Polifosfatos , Esgotos , Análise Espectral Raman
8.
Water Res ; 206: 117725, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34653799

RESUMO

Candidatus Accumulibacter phosphatis (CAP) and its clade-level micro-diversity has been associated with and implicated in functional differences in phosphorus removal performance in enhanced biological phosphorus removal (EBPR) systems. Side-stream EBPR (S2EBPR) is an emerging process that has been shown to present a suite of advantages over the conventional EBPR design, however, large knowledge gaps remain in terms of its underlying ecological mechanisms. Here, we compared and revealed the higher-resolution differences in microbial ecology of CAP between a full-scale side-stream EBPR configuration and a conventional A2O EBPR process that were operated in parallel and with the same influent feed. Even though the relative abundance of CAP, revealed by 16S rRNA gene amplicon sequencing, was similar in both treatment trains, a clade-level analysis, using combined 16S rRNA-gene based amplicon sequencing and oligotyping analysis and metagenomics analysis, revealed the distinct CAP microdiversity between the S2EBPR and A2O configurations that likely attributed to the improved performance in S2EBPR in comparison to conventional EBPR. Furthermore, genome-resolved metagenomics enabled extraction of three metagenome-assembled genomes (MAGs) belonging to CAP clades IIB (RCAB4-2), IIC (RC14) and II (RC18), from full-scale EBPR sludge for the first time, including a distinct Ca. Accumulibacter clade that is dominant and associated only with the S2EBPR configuration. The results also revealed the temporally increasing predominance of RC14, which belonged to Clade IIC, during the implementation of the S2EBPR configuration. Finally, we also show the existence of previously uncharacterized diversity of clades of CAP, namely the clades IIB and as yet unidentified clade of type II, in full-scale EBPR communities, highlighting the unknown diversity of CAP communities in full-scale EBPR systems.


Assuntos
Metagenômica , Fósforo , Reatores Biológicos , Filogenia , RNA Ribossômico 16S/genética , Rios , Esgotos
9.
Talanta ; 233: 122458, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34215099

RESUMO

Poor recovery of phosphorus (P) across natural environment (water, soil, sediment, and biological sources) is causing rapid depletion of phosphate rocks and continuous accumulation of P in natural waters, resulting in deteriorated water quality and aquatic lives. Accurate detection and characterization of various P species using suitable analytical methods provide a comprehensive understanding of the biogeochemical cycle of P and thus help its proper management in the environment. This paper aims to provide a comprehensive review of the analytical methods used for P speciation in natural environment by dividing them into five broad categories (i.e., chemical, biological, molecular, staining microscopy, and sensors) and highlighting the suitability (i.e., targeted species, sample matrix), detection limit, advantages-limitations, and reference studies of all methods under each category. This can be useful in designing studies involving P detection and characterization across environmental matrices by providing insights about a wide range of analytical methods based on the end user application needs of individual studies.


Assuntos
Meio Ambiente , Fósforo , Fosfatos/análise , Solo
10.
Water Environ Res ; 92(3): 403-417, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31402530

RESUMO

Sidestream EBPR (S2EBPR) is an emerging alternative process to address common challenges in EBPR related to weak wastewater influent and may improve EBPR process stability. A systematic evaluation and comparison of the process performance and microbial community structure was conducted between conventional and S2EBPR facilities in North America. The statistical analysis suggested higher performance stability in S2EBPR than conventional EBPR, although possible bias associated with other plant-specific factors might have affected the comparison. Variations in stoichiometric values related to EBPR activity and discrepancies between the observed values and current model predictions suggested a varying degree of metabolic versatility of PAOs in S2EBPR systems that warrant further investigation. Microbial community analysis using various techniques suggested comparable known candidate PAO relative abundances in S2EBPR and conventional EBPR systems, whereas the relative abundance of known candidate GAOs seemed to be consistently lower in S2EBPR facilities than conventional EBPR facilities. 16S rRNA gene sequencing analysis revealed differences in the community phylogenetic fingerprints between S2EBPR and conventional facilities and indicated statistically higher microbial diversity index values in S2EBPR facilities than those in conventional EBPRs. PRACTITIONER POINTS: Sidestream EBPR (S2EBPR) can be implemented with varying and flexible configurations, and they offer advantages over conventional configurations for addressing the common challenges in EBPR related to weak wastewater influent and may improve EBPR process stability. Survey of S2EBPR plants in North America suggested statistically more stable phosphorus removal performance in S2EBPR plants than conventional EBPRs, although possible bias might affect the comparison due to other plant-specific factors. The EBPR kinetics and stoichiometry of the S2EBPR facilities seemed to vary and are associated with metabolic versatility of PAOs in S2EBPR systems that warrant further investigation. The abundance of known candidate PAOs in S2EBPR plants was similar to those in conventional EBPRs, and the abundance of known candidate GAOs was generally lower in S2EBPR than conventional EBPR facilities. Further finer-resolution analysis of PAOs and GAOs, as well as identification of other unknown PAOs and GAOs, is needed. Microbial diversity is higher in S2EBPR facilities compared with conventional ones, implying that S2EBPR microbial communities could show better resilience to perturbations due to potential functional redundancy.


Assuntos
Reatores Biológicos , Fósforo , Cinética , América do Norte , Filogenia , Polifosfatos , RNA Ribossômico 16S , Inquéritos e Questionários
11.
Water Res ; 167: 115109, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31585384

RESUMO

To address the common challenges in enhanced biological phosphorus removal (EBPR) related to stability and unfavorable influent carbon to phosphorus ratio, a side-stream EBPR (S2EBPR) process that involves a side-stream anaerobic biological sludge hydrolysis and fermentation reactor was proposed as an emerging alternative. In this study, a full-scale pilot testing was performed with side-by-side operation of a conventional anaerobic-anoxic-aerobic (A2O) process versus a S2EBPR process. A comparison of the performance, activity and microbial community between the two configurations was performed. The results demonstrated that, with the same influent wastewater characteristics, S2EBPR configuration showed improved P removal performance and stability than the conventional A2O configuration, especially when the mixers in the side-stream anaerobic reactor were operated intermittently. Mass balance analysis illustrated that both denitrification and EBPR were enhanced in S2EBPR configuration, where return activated sludge was diverted into the anaerobic zone to promote fermentation and enrichment of polyphosphate accumulating organisms (PAOs), and the influent was bypassed to the anoxic zone for enhancing denitrification. A relatively higher PAO activity and total PAO abundance were observed in S2EBPR than in A2O configuration, accompanied by a higher degree of dependence on glycolysis pathway than tricarboxylic acid cycle. No significant difference in the relative abundances of putative PAOs, including Ca. Accumulibacter and Tetrasphaera, were observed between the two configurations. However, higher microbial community diversity indices were observed in S2EBPR configuration than in conventional one. In addition, consistently lower relative abundance of known glycogen accumulating organisms (GAOs) was observed in S2EBPR system. Extended anaerobic retention time and conditions that generate continuous and more complex volatile fatty acids in the side-stream anaerobic reactor of S2EBPR process likely give more competitive advantage for PAOs over GAOs. PAOs exhibited sustained EBPR activity and delayed decay under extended anaerobic condition, likely due to their versatile metabolic pathways depending on the availability and utilization of multiple intracellular polymers. This study provided new insights into the effects of implementing side-stream EBPR configuration on microbial populations, EBPR activity profiles and resulted system performance.


Assuntos
Fósforo , Rios , Reatores Biológicos , Polifosfatos , Esgotos , Águas Residuárias
12.
J Pediatr Neurosci ; 12(2): 196-198, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28904586

RESUMO

A 4-year-old boy presented with loss of motor milestones following viral fever. On examination, the child had increased tone and exaggerated deep tendon reflexes. Magnetic resonance imaging of the brain showed white matter hyperintensities on T2-weighted images, which revealed partial inversion on fluid-attenuated inversion recovery images. Clinical exome sequencing revealed a novel homozygous mutation c.1270T>G: pCys424Gly in exon 11 of the EIF2B3 gene. This novel mutation is reported in this article along with a literature review.

13.
AMB Express ; 7(1): 146, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28697582

RESUMO

Recently, the use of phototrophs for wastewater treatment has been revisited because of new approaches to separate them from effluent streams. One manifestation uses oxygenic photogranules (OPGs) which are dense, easily-settleable granular biofilms of cyanobacteria, which surrounding populations of heterotrophs, autotrophs, and microalgae. OPGs can remove COD and nitrogenous compounds without external aeration. To better grow and maintain biomass in the proposed wastewater process, this study seeks to understand the factors that contribute to successful granulation. Availability of initial inorganic nitrogen, particularly ammonium, was associated with successful cultivation of OPGs. In the first days of granulation, a decrease in ammonium coupled with an increase in a cyanobacterial-specific 16S rRNA gene, may suggest that ammonium was assimilated in cyanobacteria offering a competitive environment for growth. Though both successful and unsuccessful OPG formation demonstrated a shift from non-phototrophic bacterial dominated communities on day 0 to cyanobacterial dominated communities on day 42, the successful community had a greater relative abundance (46%) of OTUs associated with genera Oscillatoria and Geitlernema than the unsuccessful community (27%), supporting that filamentous cyanobacteria are essential for successful OPG formation. A greater concentration of chlorophyll b in the unsuccessful OPG formation suggested a greater abundance of algal species. This study offers indicators of granulation success, notably availability of inorganic nitrogen and chlorophyll a and b concentrations for monitoring the health and growth of biomass for a potential OPG process.

14.
J Pediatr Neurosci ; 12(1): 78-79, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28553389

RESUMO

Sandhoff disease is a neurodegenerative disease caused due to deficiency of hexosaminidase (HEX) A and B. A 1-year-old male child presented with regression of milestones, exaggerated startle response, decreased vision, and seizures from 6 months of age. The child had coarse facies without hepatosplenomegaly. Serum levels of ß hexosaminidase total (A + B) were low. Genetic testing for Sandhoff disease revealed a homozygous missense variant on HEXB gene. The case is presented to highlight that the absence of hepatosplenomegaly should not restrain in suspecting Sandhoff disease.

15.
Environ Sci Technol ; 51(9): 5334-5342, 2017 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-28374997

RESUMO

A poorly understood phenomenon with a potentially significant impact on electron recovery is competition in microbial fuel cells (MFC) between anode-respiring bacteria and microorganisms that use other electron acceptors. Nitrate is a constituent of different wastewaters and can act as a competing electron acceptor in the anode. Studies investigating the impact of competition on population dynamics in mixed communities in the anode are lacking. Here, we investigated the impact of nitrate at different C/N ratios of 1.8, 3.7, and 7.4 mg C/mg N on the electrochemical performance and the biofilm community in mixed-culture chemostat MFCs. The electrochemical performance of the MFC was not affected under electron donor non-limiting conditions, 7.4 mg C/mg N. At lower C/N, electron donor limiting and ratio electron recovery were significantly affected. The electrochemical performance recovered upon removal of nitrate at 3.7 mg C/mg N but did not at 1.8 mg C/mg N. Microbial community analysis showed a decrease in Deltaproteobacteria accompanied by an increase in Betaproteobacteria in response to nitrate at low C/N ratios and no significant changes at 7.4 mg C/mg N. Transcriptional analysis showed increased transcription of nirK and nirS genes during nitrate flux, suggesting that denitrification to N2 and not facultative nitrate reduction by Geobacter spp. might be the primary response to perturbation with nitrate.


Assuntos
Fontes de Energia Bioelétrica/microbiologia , Eletrodos , Desnitrificação , Geobacter , Nitratos
16.
Indian J Pediatr ; 84(5): 403-404, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28138907

RESUMO

A patient with Sialidosis type 1 with a novel variation in neuraminidase-1 (NEU1) is described. The patient developed ataxia and myoclonus at 9 y of age. He was born to a second degree consanguineous marriage couple. On examination child had cerebellar signs and bilateral macular cherry-red spots. MRI of the brain and electroencephalogram were normal. The enzyme analysis revealed deficiency of neuraminidase. Genetic analysis identified novel homozygous missense mutation c.742G > T (p.G248C) in exon 4 of NEU1 gene. At 13 y of age, the ataxia and had myoclonus progressed.


Assuntos
Mucolipidoses/genética , Mutação de Sentido Incorreto/genética , Neuraminidase/genética , Criança , Consanguinidade , Homozigoto , Humanos , Masculino
17.
Brain Dev ; 38(8): 759-62, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26992473

RESUMO

BACKGROUND: Canavan disease is an autosomal recessive disorder with spongy degeneration of white matter of the brain. It presents with developmental delay, visual problems and macrocephaly. PATIENT DESCRIPTION: We report a ten-month old boy with Canavan disease who presented with global developmental delay, seizures, abnormal eye movements and microcephaly. RESULTS: MRI brain revealed diffuse involvement of the supra tentorial white matter, globus pallidi, thalami, dentate nuclei and brainstem with sparing of the corpus callosum. The genetic testing revealed homozygous mutation of aspartoacylase gene [c.859 G>A (p.Ala287Thr)] in Exon 6. CONCLUSION: Possibility of Canavan disease should be considered even in the presence of microcephaly.


Assuntos
Encéfalo/diagnóstico por imagem , Doença de Canavan/diagnóstico , Microcefalia/diagnóstico , Amidoidrolases/genética , Doença de Canavan/genética , Doença de Canavan/fisiopatologia , Deficiências do Desenvolvimento/diagnóstico , Deficiências do Desenvolvimento/genética , Deficiências do Desenvolvimento/fisiopatologia , Diagnóstico Diferencial , Humanos , Lactente , Imageamento por Ressonância Magnética , Masculino , Microcefalia/genética , Microcefalia/fisiopatologia , Convulsões/diagnóstico , Convulsões/genética , Convulsões/fisiopatologia
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