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1.
Metab Eng ; 72: 337-352, 2022 07.
Article in English | MEDLINE | ID: mdl-35545205

ABSTRACT

Polyethylene terephthalate (PET), the most common synthetic polyester today, is largely produced from fossil resources, contributing to global warming. Consequently, sustainable sources must be developed to meet the increasing demand for this useful polymer. Here, we demonstrate a cascaded value chain that provides green PET from lignin, the world's most underutilized renewable, via fermentative production of cis, cis-muconate (MA) from lignin-based aromatics as a central step. Catechol, industrially the most relevant but apparently also a highly toxic lignin-related aromatic, strongly inhibited MA-producing Pseudomonas putida MA-1. Assessed by 13C metabolic flux analysis, the microbe substantially redirected its carbon core fluxes, resulting in enhanced NADPH supply for stress defense but causing additional ATP costs. The reconstruction of MA production in a genome-reduced P. putida chassis yielded novel producers with superior pathway fluxes and enhanced robustness to catechol and a wide range of other aromatics. Using the advanced producer P. putida MA-10 catechol, MA could be produced in a fed-batch process from catechol (plus glucose as additional growth substrate) up to an attractive titer of 74 g L-1 and a space-time-yield of 1.4 g L-1 h-1. In terms of co-consumed sugar, the further streamlined strain MA-11 achieved the highest yield of 1.4 mol MA (mol glucose)-1, providing a striking economic advantage. Following fermentative production, bio-based MA was purified and used to chemically synthetize the PET monomer terephthalic acid and the comonomer diethylene glycol terephthalic acid through five steps, which finally enabled the first green PET from lignin.


Subject(s)
Pseudomonas putida , Catechols/metabolism , Glucose/metabolism , Lignin/metabolism , Oxidation-Reduction , Polyethylene Terephthalates/metabolism , Pseudomonas putida/genetics , Pseudomonas putida/metabolism
2.
Appl Microbiol Biotechnol ; 104(18): 7745-7766, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32789744

ABSTRACT

Pseudomonas putida is a Gram-negative, rod-shaped bacterium that can be encountered in diverse ecological habitats. This ubiquity is traced to its remarkably versatile metabolism, adapted to withstand physicochemical stress, and the capacity to thrive in harsh environments. Owing to these characteristics, there is a growing interest in this microbe for industrial use, and the corresponding research has made rapid progress in recent years. Hereby, strong drivers are the exploitation of cheap renewable feedstocks and waste streams to produce value-added chemicals and the steady progress in genetic strain engineering and systems biology understanding of this bacterium. Here, we summarize the recent advances and prospects in genetic engineering, systems and synthetic biology, and applications of P. putida as a cell factory. KEY POINTS: • Pseudomonas putida advances to a global industrial cell factory. • Novel tools enable system-wide understanding and streamlined genomic engineering. • Applications of P. putida range from bioeconomy chemicals to biosynthetic drugs.


Subject(s)
Pseudomonas putida , Biotechnology , Genomics , Pseudomonas putida/genetics , Synthetic Biology , Systems Biology
3.
Fam Med Community Health ; 12(1)2024 Mar 14.
Article in English | MEDLINE | ID: mdl-38485284

ABSTRACT

INTRODUCTION: Pelvic floor disorders (PFDs) pose substantial physical and psychological burdens for a growing number of women. Given the ubiquity of these conditions and known patient reluctance to seek care, primary care providers (PCPs) have a unique opportunity to increase treatment and provide appropriate referrals for these patients. METHODS: An online survey was administered to PCPs to assess provider practices, knowledge, comfort managing and ease of referral for PFDs. Logistic regression was used to assess the association between demographic/practice characteristics of PCPs and two primary outcomes of interest: discomfort with management and difficulty with referral of PFDs. RESULTS: Of the 153 respondents to the survey, more felt comfortable managing stress urinary incontinence (SUI) and overactive bladder (OAB), compared with pelvic organ prolapse (POP) and faecal incontinence (FI) and were less likely to refer patients with urinary symptoms. Few providers elicited symptoms for POP and FI as compared with SUI and OAB. Provider variables that were significantly associated with discomfort with management varied by PFD, but tended to correlate with less exposure to PFDs (eg, those with fewer years of practice, and internal medicine and family physicians as compared with geriatricians); whereas the factors that were significantly associated with difficulty in referral, again varied by PFD, but were related to practice characteristics (eg, specialist network, type of practice, practice setting and quantity of patients). CONCLUSION: These findings highlight the need to increase PCPs awareness of PFDs and develop effective standardised screening protocols, as well as collaboration with pelvic floor specialists to improve screening, treatment and referral for patients with PFDs.


Subject(s)
Fecal Incontinence , Pelvic Floor Disorders , Pneumonia, Pneumocystis , Urinary Bladder, Overactive , Urinary Incontinence, Stress , Humans , Female , Pelvic Floor Disorders/diagnosis , Pelvic Floor Disorders/therapy , Pelvic Floor Disorders/complications , Cross-Sectional Studies , Urinary Bladder, Overactive/diagnosis , Urinary Bladder, Overactive/therapy , Urinary Bladder, Overactive/complications , Urinary Incontinence, Stress/diagnosis , Urinary Incontinence, Stress/therapy , Urinary Incontinence, Stress/complications , Pneumonia, Pneumocystis/complications , Fecal Incontinence/diagnosis , Fecal Incontinence/therapy , Fecal Incontinence/complications , Primary Health Care
4.
Am J Clin Oncol ; 2024 Jul 08.
Article in English | MEDLINE | ID: mdl-38973252

ABSTRACT

OBJECTIVE: We aim to explore whether the surgical tumor free margin is important for overall survival (OS) and local control in patients who undergo neoadjuvant radiation (RT) for vulvar cancer. METHODS: A retrospective review from 2004 to 2021 of patients who underwent RT followed by surgical resection was performed. Patients were categorized into groups based on margin status (no residual disease, >8 mm, close margins defined as 1 to 7 mm, or positive). Local control and OS were analyzed using the Kaplan-Meier with log rank test. Multivariate analysis was performed with cox hazards model. RESULTS: Eighty-three patients were included. A complete pathologic response (pCR) was found in 56% (n=46) of patients. The median follow-up time was 35 months (range: 4 to 216). The median OS for the entire cohort was 46 months (95% CI: 32.3-59.7). Having a pCR improved both OS and disease-free survival (DFS) compared with residual disease by 81 and 91 months, respectively (P<0.001). In the 2 patients with a margin >8 mm, there was no statistical difference in survival between those with close margins (46 vs. 25 mo, P=0.485). Factors that significantly impacted both OS and DFS were depth of invasion (DOI) and LVSI. On multivariate analysis of those with residual disease, there was no difference in OS or DFS by margin status but having a DOI >9 mm showed decreased OS (HR: 3.654; 95% CI: 1.317-10.135). CONCLUSIONS: In this cohort, response to RT, not margin status drives survival and recurrence. Given residual disease, the optimal margin is not clear, as there were only 2 patients with >8 mm margins. A close or positive margin had no impact on OS or local recurrence. A DOI >9 mm significantly impacts both OS and local recurrence even when accounting for other factors.

5.
Microb Biotechnol ; 17(1): e14375, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37990843

ABSTRACT

Providing an anodic potential in a bio-electrochemical system to the obligate aerobe Pseudomonas putida enables anaerobic survival and allows the cells to overcome redox imbalances. In this setup, the bacteria could be exploited to produce chemicals via oxidative pathways at high yield. However, the absence of anaerobic growth and low carbon turnover rates remain as obstacles for the application of such an electro-fermentation technology. Growth and carbon turnover start with carbon uptake into the periplasm and cytosol. P. putida KT2440 has three native transporting systems for glucose, each differing in energy and redox demand. This architecture previously led to the hypothesis that internal redox and energy constraints ultimately limit cytoplasmic carbon utilization in a bio-electrochemical system. However, it remains largely unclear which uptake route is predominantly used by P. putida under electro-fermentative conditions. To elucidate this, we created three gene deletion mutants of P. putida KT2440, forcing the cells to exclusively utilize one of the routes. When grown in a bio-electrochemical system, the pathway mutants were heavily affected in terms of sugar consumption, current output and product formation. Surprisingly, however, we found that about half of the acetate formed in the cytoplasm originated from carbon that was put into the system via the inoculation biomass, while the other half came from the consumption of substrate. The deletion of individual sugar uptake routes did not alter significantly the secreted acetate concentrations among different strains even with different carbon sources. This means that the stoichiometry of the sugar uptake routes is not a limiting factor during electro-fermentation and that the low rates might be caused by other reasons, for example energy limitations or a yet-to-be-identified oxygen-dependent regulatory mechanism.


Subject(s)
Pseudomonas putida , Pseudomonas putida/metabolism , Anaerobiosis , Glucose/metabolism , Carbon/metabolism , Acetates/metabolism
6.
Front Artif Intell ; 4: 725321, 2021.
Article in English | MEDLINE | ID: mdl-35187471

ABSTRACT

Literary narratives regularly contain passages that different readers attribute to different speakers: a character, the narrator, or the author. Since literary narratives are highly ambiguous constructs, it is often impossible to decide between diverging attributions of a specific passage by hermeneutic means. Instead, we hypothesise that attribution decisions are often influenced by annotator bias, in particular an annotator's literary preferences and beliefs. We present first results on the correlation between the literary attitudes of an annotator and their attribution choices. In a second set of experiments, we present a neural classifier that is capable of imitating individual annotators as well as a common-sense annotator, and reaches accuracies of up to 88% (which improves the majority baseline by 23%).

7.
PLoS Negl Trop Dis ; 13(8): e0007632, 2019 08.
Article in English | MEDLINE | ID: mdl-31412024

ABSTRACT

BACKGROUND: Babesia, a tick-borne genus of intraerythrocytic parasites, is understudied in humans outside of established high-endemic areas. There is a paucity of data on Babesia in Africa, despite evidence that it is regionally present. A pilot study suggested that Babesia was present in a rural district of Tanzania. METHODOLOGY/PRINCIPAL FINDINGS: A cross-sectional study was conducted July-August 2017: residents in a case hamlet that had clustering of subjects with high signal-to-cut off (S/CO) ratios for antibodies against B. microti in the pilot study, and a control hamlet that had lacked significant signal, were evaluated for B. microti. Subjects aged ≥15yrs (n = 299) underwent clinical evaluation and household inspections; 10ml whole blood was drawn for Babesia transcription mediated amplification (TMA), B. microti indirect fluorescent antibody testing (IFA) and rapid diagnostic testing (RDT) for Plasmodium spp. Subjects aged <15yrs (n = 266) underwent a RDT for Plasmodium and assessment by ELISA for B. microti antibodies. A total of 570 subjects participated (mean age 22 [<1 to 90yrs]) of whom 50.7% were female and 145 (25.5%) subjects were Plasmodium RDT positive (+). In those <15yrs, the median ELISA S/CO was 1.11 (IQR 0.80-1.48); the median S/CO in the case (n = 120) and control (n = 146) hamlets was 1.19 (IQR 0.81-1.48) and 1.06 (IQR 0.80-1.50) respectively (p = 0.4). Children ≥5yrs old were more likely to have a higher S/CO ratio than those <5yrs old (p<0.001). One hundred (38%) subjects <15yrs were Plasmodium RDT+. The median S/CO ratio (children <15yrs) did not differ by RDT status (p = 0.15). In subjects ≥15yrs, no molecular test was positive for Babesia, but four subjects (1.4%) were IFA reactive (two each at titers of 128 and 256). CONCLUSIONS/SIGNIFICANCE: The findings offer further support for Babesia in rural Tanzania. However, low prevalence of seroreactivity questions its clinical significance.


Subject(s)
Antibodies, Protozoan/blood , Babesia/immunology , Babesiosis/epidemiology , Babesiosis/immunology , Adolescent , Adult , Aged , Aged, 80 and over , Babesiosis/blood , Babesiosis/parasitology , Child , Child, Preschool , Cross-Sectional Studies , Enzyme-Linked Immunosorbent Assay , Female , Humans , Infant , Male , Middle Aged , Pilot Projects , Plasmodium/immunology , Tanzania/epidemiology , Young Adult
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