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1.
Mar Policy ; 140: 105054, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35399704

ABSTRACT

The human response to the COVID-19 pandemic set in motion an unprecedented shift in human activity with unknown long-term effects. The impacts in marine systems are expected to be highly dynamic at local and global scales. However, in comparison to terrestrial ecosystems, we are not well-prepared to document these changes in marine and coastal environments. The problems are two-fold: 1) manual and siloed data collection and processing, and 2) reliance on marine professionals for observation and analysis. These problems are relevant beyond the pandemic and are a barrier to understanding rapidly evolving blue economies, the impacts of climate change, and the many other changes our modern-day oceans are undergoing. The "Our Ocean in COVID-19″ project, which aims to track human-ocean interactions throughout the pandemic, uses the new eOceans platform (eOceans.app) to overcome these barriers. Working at local scales, a global network of ocean scientists and citizen scientists are collaborating to monitor the ocean in near real-time. The purpose of this paper is to bring this project to the attention of the marine conservation community, researchers, and the public wanting to track changes in their area. As our team continues to grow, this project will provide important baselines and temporal patterns for ocean conservation, policy, and innovation as society transitions towards a new normal. It may also provide a proof-of-concept for real-time, collaborative ocean monitoring that breaks down silos between academia, government, and at-sea stakeholders to create a stronger and more democratic blue economy with communities more resilient to ocean and global change.

5.
J Plast Reconstr Aesthet Surg ; 73(5): 951-958, 2020 May.
Article in English | MEDLINE | ID: mdl-32063454

ABSTRACT

BACKGROUND: Long-term follow-up after short-term reconstructive missions is challenging, often due to financial constraints, remote geography and lack of post-operative communication with patients. The aim of this study was to conduct long-term follow-up of patients who have undergone surgery for complex facial disfigurement in Ethiopia. METHODS: A retrospective cohort study was conducted in Ethiopia over a 2-week period between February and March 2017. All patients who were previously operated on by the charity Project Harar were eligible. Data were collected from semi-structured interviews and clinical examinations. RESULTS: Seventy patients (41 males: 29 females) were included in this study. This equates to a follow-up rate of 20% (70/350) of all patients operated on by the charity since 2008. Mean patient age was 26.8 years (range, 3-61 years). The most common pathologies were noma (24%), ameloblastoma (16%) and trauma (11%). The mean follow-up time after final surgery was 47 months (range, 12-180) with an average of 1.3 (range, 1-6) operations per patient. Long-term complications were reported by 30% of patients, with chronic fistula (n = 6) and chronic infection (n = 3) the most common. Following surgery, stigma experienced by patients decreased from 92% to 3%. CONCLUSIONS: This study demonstrates that complex head and neck reconstruction can be safely undertaken in resource-limited settings with improvements in stigma experienced and quality of life for patients. However, despite a decade of experience and refinements, early and late complications do occur, and this should be factored into pre-mission planning and careful follow-up. New, cost-neutral follow-up protocols are being developed.


Subject(s)
Esthetics , Head/surgery , Medical Missions , Neck/surgery , Plastic Surgery Procedures/methods , Adolescent , Adult , Child , Child, Preschool , Ethiopia , Female , Humans , Male , Middle Aged , Postoperative Complications , Quality of Life , Retrospective Studies , Social Stigma
6.
Surgeon ; 18(5): e1-e6, 2020 Oct.
Article in English | MEDLINE | ID: mdl-31718929

ABSTRACT

BACKGROUND: Changes to working practices and increasing service demand have contributed to low morale amongst UK surgical trainees, with pressures particularly acute 'out of hours' (OOH). Surgeons may be expected to be 'on call' for multiple hospitals, or to provide remote consultations, yet healthcare systems may undermine their professional safety and patient care. This cross-sectional study sought to define the perceptions of UK-based Royal College of Surgeons of Edinburgh (RCSEd) affiliated trainees of OOH surgical care and training. METHODS: The RCSEd Trainees' Committee conducted a design-thinking exercise to produce an online questionnaire. Non-consultant grade RCSEd Members and Fellows were invited to participate. Quantitative data was analysed using descriptive statistics, and qualitative data was coded to identify emergent themes. RESULTS: One hundred and fifty-five surgeons participated. Of those surgeons working in multiple hospitals OOH (n = 16), many did not receive access cards (12[75%]) or site-specific induction (13[81%]), and 8(50%) were not confident in using local electronic investigation and records systems. Only 14/114 (12%) of the surgeons providing remote opinion had access to a consultation record system, and most perceived dissatisfaction with the system. Emergent themes from qualitative data revealed that trainee surgeons desire specific training in OOH working, concerns that OOH work experience is diminishing, and that hospital infrastructure such as IT and communications, rest facilities and catering were inadequate in facilitating safe care. CONCLUSIONS: The participants perceived that the systems supporting delivery of safe surgical care OOH were inadequate. Hospital leaders should ensure that systems minimise risk to staff and patients.


Subject(s)
After-Hours Care/organization & administration , Education, Medical, Graduate/organization & administration , General Surgery/education , Personnel Staffing and Scheduling/organization & administration , State Medicine , Clinical Competence , Cross-Sectional Studies , Humans , Surveys and Questionnaires , United Kingdom , Workload
8.
Ann R Coll Surg Engl ; 98(1): 71, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26688411
9.
Article in English | MEDLINE | ID: mdl-22709629

ABSTRACT

Downstream purification often represents the most cost-intensive step in the manufacturing of recombinant proteins since conventional purification processes are lengthy, technically complicated, and time-consuming. To address this issue, herein we demonstrated the simultaneous clarification and purification of the extracellularly produced recombinant protein by Escherichia coli using an integrated system of tangential flow filtration and anion exchange membrane chromatography (TFF-AEMC). After cultivation in a bench-top bioreactor with 1L working volume using the developed host/vector system for high-level expression and effective secretion of recombinant penicillin G acylase (PAC), the whole culture broth was applied directly to the established system. One-step purification of recombinant PAC was achieved based on the dual nature of membrane chromatography (i.e. microfiltration-sized pores and anion-exchange chemistry) and cross-flow operations. Most contaminant proteins in the extracellular medium were captured by the anion-exchange membrane and cells remained in the retentate, whereas extracellular PAC was purified and collected in the filtrate. The batch time for both cultivation and purification was less than 24h and recombinant PAC with high purity (19 U/mg), yield (72% recovery), and productivity (41 mg of purified PAC per liter of culture) was obtained. Due to the nature of the non-selective protein secretion system and the versatility of ion-exchange membrane chromatography, the developed system can be widely applied for effective production and purification of recombinant proteins.


Subject(s)
Chromatography, Ion Exchange/methods , Escherichia coli/enzymology , Penicillin Amidase/isolation & purification , Recombinant Proteins/isolation & purification , Ultrafiltration/methods , Anions/chemistry , Bioreactors , Escherichia coli/growth & development , Penicillin Amidase/chemistry , Penicillin Amidase/metabolism , Recombinant Proteins/chemistry , Recombinant Proteins/metabolism
10.
J Biotechnol ; 161(1): 19-26, 2012 Sep 15.
Article in English | MEDLINE | ID: mdl-22728392

ABSTRACT

An integrated bioprocess for effective production and purification of penicillin G acylase (PAC) was developed. PAC was overexpressed in a genetically engineered Escherichia coli strain, secreted into the cultivation medium, harvested, and purified in a single step by anion-exchange chromatography. The cultivation medium developed in this study had a sufficiently low conductivity to allow direct application of the extracellular fraction to the anion-exchange chromatography column while providing all of the required nutrients for sustaining cell growth and PAC overexpression. It was contrived with the purposes of (i) providing sufficient osmolarity and buffering capacity, (ii) minimizing ionic species to facilitate the binding of extracellular proteins to anion-exchange media, and (iii) enhancing PAC expression level and secretion efficiency. Employing this medium recipe the specific PAC activity reached a high level at 871 U/g DCW, of which more than 90% was localized in the extracellular medium. In addition, the osmotic pressure and induction conditions were found to be critical for optimal culture performance. The formation of inclusion bodies associated with PAC overexpression tended to arrest cell growth, leading to potential cell lysis. Clarified culture medium was applied to a strong anion-exchange (Q) column and PAC was purified by non-retentive separation, where most contaminant proteins bound to the chromatographic media with PAC being collected as the major component in the flow-through fraction. After removing the contaminant oligopeptides using ultrafiltration, purified PAC with a specific activity of 16.3 U/mg was obtained and the overall purification factor for this one-step downstream purification process was up to 3 fold.


Subject(s)
Biotechnology/methods , Escherichia coli/metabolism , Industrial Microbiology/methods , Penicillin Amidase/biosynthesis , Penicillin Amidase/isolation & purification , Blotting, Western , Chromatography, Ion Exchange , Electrophoresis, Polyacrylamide Gel , Escherichia coli/genetics , Genetic Engineering/methods , Inclusion Bodies/metabolism , Ultrafiltration
11.
J Chromatogr B Analyt Technol Biomed Life Sci ; 879(9-10): 564-72, 2011 Mar 15.
Article in English | MEDLINE | ID: mdl-21315664

ABSTRACT

The potential application of a hydrogel-based strong anion-exchange (Q) membrane to purify plasmid DNAs was evaluated. The maximum binding capacity of plasmid DNA was estimated to be 12.4 mg/ml of membrane volume with a plasmid recovery yield of ∼90%. The effect of the inherent properties of plasmid DNA, membrane adsorbent, and the ionic environment on membrane performance was systematically investigated. Plasmid DNAs with smaller tertiary structure tended to have a better recovery than those with larger tertiary structure. Environmental Scanning Electron Microscopy (ESEM) revealed that the hydrogel structure is more porous on one side of membrane than the other. Membrane pre-treatment significantly improved pore distribution and increased membrane porosity resulting in a better adsorption, recovery, and higher flux. The selection of proper operating pH led to further improvement. The relative contribution of these factors to improve membrane chromatography of plasmid DNAs was analyzed using statistical modeling. It was found that the adsorption of plasmid DNA was mainly affected by the available adsorptive area associated with membrane porosity, whereas the recovery of plasmid DNAs was mainly affected by the environmental pH.


Subject(s)
Chromatography, Ion Exchange/methods , DNA, Superhelical/isolation & purification , Hydrogel, Polyethylene Glycol Dimethacrylate/chemistry , Plasmids/isolation & purification , Anions/chemistry , DNA, Superhelical/chemistry , Escherichia coli , Hydrogen-Ion Concentration , Microscopy, Electron, Scanning , Plasmids/genetics
12.
Inorg Chem ; 40(7): 1489-95, 2001 Mar 26.
Article in English | MEDLINE | ID: mdl-11261955

ABSTRACT

The reaction of TaCl5 with a single equivalent of Cl3P=NSiMe3 resulted in the isolation of the perhalogenated (phosphoraniminato) tantalum(V) complex TaCl4(N=PCl3) (1). Reaction of 1 with an excess of THF and subsequent cooling produced crystals of TaCl4(N=PCl3)(THF) (1.THF), which possesses a distorted octahedral Ta center with a THF molecule coordinated trans to the phosphoraniminato ligand. The reaction of 1 with the aminophosphoranimine, (Me3Si)2NPCl2=NSiMe3, resulted in a [3 + 1] cyclocondensation reaction to form the metallacyclic complex, TaCl3(N=PCl3)[N(SiMe3)PCl2N(SiMe3)] (2), which contains a TaNPN four-membered ring and a phosphoraniminato ligand (N=PCl3). The analogous [3 + 1] cyclocondensation reaction between (Me3Si)2NPCl2=NSiMe3 and TaCl5 led to the isolation of TaCl4[N(SiMe3)PCl2N(SiMe3)] (3). An attempt to cleave the NPN ligand from the Ta center in 2 via protonolysis with HCl led to an unusual phosphoraniminato ligand coupling reaction to yield the novel phosphazenium salt [N(PCl2NH2)2][TaCl6] (4). All new compounds (1.THF and complexes 1-4) were characterized by single-crystal X-ray diffraction.

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