Abstract In the absence of liquid suspension, dry biofilms can form upon hard surfaces within a hospital environment, representing a healthcare‐associated infection risk. Probiotic cleansers using generally recognized as safe organisms, such as those of the Bacillus genus, represent a potential strategy for the reduction of dry biofilm bioburden. The mechanisms of action and efficacy of these cleaners are, however, poorly understood. To address this, a preventative dry biofilm assay was developed using steel, melamine, and ceramic surfaces to assess the ability of a commercially available Bacillus spp. based probiotic cleanser to reduce the surface bioburden of Escherichia coli and Staphylococcus aureus. Via this assay, phosphate‐buffered saline controls were able to generate dry biofilms within 7 days of incubation, with the application of the probiotic cleanser able to prevent >97.7% of dry biofilm formation across both pathogen analogs and surface types. Further to this, surfaces treated with the probiotic mixture alone also showed a reduction in dry biofilm across both pathogen and surface types. Confocal laser scanning microscopy imaging indicated that the probiotic bacteria were able to germinate and colonize surfaces, likely forming a protective layer upon these hard surfaces.
Extremes of pH present a challenge to microbial life and our understanding of survival strategies for microbial consortia, particularly at high pH, remains limited. The utilization of extracellular polymeric substances within complex biofilms allows micro-organisms to obtain a greater level of control over their immediate environment. This manipulation of the immediate environment may confer a survival advantage in adverse conditions to biofilms. Within the present study alkaliphilic biofilms were created at pH 11.0, 12.0, or 13.0 from an existing alkaliphilic community. In each pH system, the biofilm matrix provided pH buffering, with the internal pH being 1.0-1.5 pH units lower than the aqueous environment. Increasing pH resulted in a reduced removal of substrate and standing biomass associated with the biofilm. At the highest pH investigated (pH 13.0), the biofilms matrix contained a greater degree of eDNA and the microbial community was dominated by Dietzia sp. and Anaerobranca sp.
This study examined the level of knowledge and skills on the use of e-learning among lecturers and student at the Open University of Tanzania. The study was guided by one research question and one hypothesis. The study was also guided by Dynamic Skills Theory developed by Fischer in 1980. The study employed convergent design under mixed research approach. The target population involves 2616 students, 303 lecturers, 50 instructional designers, 01 Director of Quality Assurance, and 01 Director of Examination Syndicate. The sample of this study included 262 students, 30 lecturers, 01 director of quality assurance, 01 director of examination syndicate, 05 instructional designers. Stratified, simple random, and purposeful sampling techniques were used to determine the study sample that consisted of 299 respondents. Research instruments included questionnaires, interview guides, and document analysis schedule. For quantitative data analysis the researcher used both descriptive and inferential statistics. For qualitative data analysis the researcher used thematic analysis for analyzing qualitative data. Data for both quantitative and qualitative are presented using tables, charts, figures, narrations, themes, categories and direct quotations were used to present the study findings. The findings indicated that a moderate majority of lecturers and majority of students perceived had lack knowledge and skills on the use of e-learning. The average mean score for lecturers and students was 2.97 and 2.25 respectively. This indicated that there was disagreement on the perceived level of knowledge and skills on the use of e-learning among lectures and students. Moreover, the findings indicated that there is no significant difference mean score between arts students and science students on the perceived level of knowledge and skills on the e-learning at the Open University of Tanzania. The study concluded that both lecturers and students had perceived inadequate knowledge and skills on the use of e-learning. The study recommends, that The Open Universities of Tanzania with collaboration of Institute of Education Management and Technology should provide training for both lecturers and students on issues regarding utilization of e-learning.
Background Progress in health service quality is vital to reach the target of Universal Health Coverage. However, in order to improve quality, it must be measured, and the assessment results must be actionable. We analyzed an electronic tool, which was developed to assess and monitor the quality of primary healthcare in Tanzania in the context of routine supportive supervision. The electronic assessment tool focused on areas in which improvements are most effective in order to suit its purpose of routinely steering improvement measures at local level. Methods Due to the lack of standards regarding how to best measure quality of care, we used a range of different quantitative and qualitative methods to investigate the appropriateness of the quality assessment tool. The quantitative methods included descriptive statistics, linear regression models, and factor analysis; the qualitative methods in-depth interviews and observations. Results Quantitative and qualitative results were overlapping and consistent. Robustness checks confirmed the tool’s ability to assign scores to health facilities and revealed the usefulness of grouping indicators into different quality dimensions. Focusing the quality assessment on processes and structural adequacy of healthcare was an appropriate approach for the assessment’s intended purpose, and a unique key feature of the electronic assessment tool. The findings underpinned the accuracy of the assessment tool to measure and monitor quality of primary healthcare for the purpose of routinely steering improvement measures at local level. This was true for different level and owner categories of primary healthcare facilities in Tanzania. Conclusion The electronic assessment tool demonstrated a feasible option for routine quality measures of primary healthcare in Tanzania. The findings, combined with the more operational results of companion papers, created a solid foundation for an approach that could lastingly improve services for patients attending primary healthcare. However, the results also revealed that the use of the electronic assessment tool outside its intended purpose, for example for performance-based payment schemes, accreditation and other systematic evaluations of healthcare quality, should be considered carefully because of the risk of bias, adverse effects and corruption.
Lime manufacture in the UK has resulted in the generation of a number of alkaline sites (>pH 11.0) with complex indigenous microbial populations. Within the present study, retrievable cotton samples were used to investigate the fate of cellulose, the primary carbon source, within three sites aged from approximate to 25 to 140years. Following 3 months incubation in situ, biofilms had formed on all cotton samples in these extreme pH conditions; with matrices comprised of carbohydrates, proteins, lipids and eDNA. Biofilms from the older sites contained greater amounts of eDNA, a structural component that aids the production of a denser biofilm. The age of the sites correlated with a shift from polysaccharides composed of 1,4 and 1,3 linked sugars to those composed of pyranosyl sugars within the older sites. These changes were reflected in the active biofilm communities which shifted from being Clostridiales dominated in the youngest site to Proteobacteria dominated in the older sites. The study demonstrates that the microbial communities resident in anthropogenic alkaline sites are able to form biofilms at pH values>pH 11.0 and that these biofilms evolve toward Proteobacteria dominated communities employing eDNA and pyranosyl sugar based polysaccharides to build the biofilm matrix.
Background Universal Health Coverage only leads to the desired health outcomes if quality of health services is ensured. In Tanzania, quality has been a major concern for many years, including the problem of ineffective and inadequate routine supportive supervision of healthcare providers by council health management teams. To address this, we developed and assessed an approach to improve quality of primary healthcare through enhanced routine supportive supervision. Methods Mixed methods were used, combining trends of quantitative quality of care measurements with qualitative data mainly collected through in-depth interviews. The former allowed for identification of drivers of quality improvements and the latter investigated the perceived contribution of the new supportive supervision approach to these improvements. Results The results showed that the new approach managed to address quality issues that could be solved either solely by the healthcare provider, or in collaboration with the council. The new approach was able to improve and maintain crucial primary healthcare quality standards across different health facility level and owner categories in various contexts. Conclusion Together with other findings reported in companion papers, we could show that the new supportive supervision approach not only served to assess quality of primary healthcare, but also to improve and maintain crucial primary healthcare quality standards. The new approach therefore presents a powerful tool to support, guide and drive quality improvement measures within council. It can thus be considered a suitable option to make routine supportive supervision more effective and adequate.
14C is an important consideration within safety assessments for proposed geological disposal facilities for radioactive wastes, since it is capable of re-entering the biosphere through the generation of 14C bearing gases. The irradiation of graphite moderators in the UK gas-cooled nuclear power stations has led to the generation of a significant volume of 14C-containing intermediate level wastes. Some of this 14C is present as a carbonaceous deposit on channel wall surfaces. Within this study, the potential of biofilm growth upon irradiated and 13C doped graphite at alkaline pH was investigated. Complex biofilms were established on both active and simulant samples. High throughput sequencing showed the biofilms to be dominated by Alcaligenes sp at pH 9.5 and Dietzia sp at pH 11.0. Surface characterisation revealed that the biofilms were limited to growth upon the graphite surface with no penetration of the deeper porosity. Biofilm formation resulted in the generation of a low porosity surface layer without the removal or modification of the surface deposits or the release of the associated 14C/13C. Our results indicated that biofilm formation upon irradiated graphite is likely to occur at the pH values studied, without any additional release of the associated 14C.
Alkaline environments represent a significant challenge to the growth of micro-organisms. Despite this, there are a number of alkaline environments which contain active microbial communities. Here we describe the genome of a diazotrophic, alkalitolerant strain of Azonexus, which was isolated from a microcosm seeded with hyperalkaline soils resulting from lime depositions. The isolate has a genome size 3.60 Mb with 3431 protein coding genes. The proteome indicated the presence of genes associated with the cycling of nitrogen, in particular the fixation of atmospheric nitrogen. Although closely related to Azonexus hydrophilus strain d8-1 by both 16S (97.9%) and in silico gDNA (84.1%) relatedness, the isolate demonstrates a pH tolerance above that reported for this strain. The proteome contained genes for the complete Na+/H+ antiporter (subunits A to G) for cytoplasmic pH regulation; this may account for the phenotypic characteristics of this strain which exhibited optimal growth conditions of pH 9 and 30°C.
Effective supportive supervision of healthcare services is crucial for improving and maintaining quality of care. However, this process can be challenging in an environment with chronic shortage of qualified human resources, overburdened healthcare providers, multiple roles of district managers, weak supply chains, high donor fragmentation and inefficient allocation of limited financial resources. Operating in this environment, we systematically evaluated an approach developed in Tanzania to strengthen the implementation of routine supportive supervision of primary healthcare providers. The approach included a systematic quality assessment at health facilities using an electronic tool and subsequent result dissemination at council level. Mixed methods were used to compare the new supportive supervision approach with routine supportive supervision. Qualitative data was collected through in-depth interviews in three councils. Observational data and informal communication as well as secondary data complemented the data set. Additionally, an economic costing analysis was carried out in the same councils. Compared to routine supportive supervision, the new approach increased healthcare providers' knowledge and skills, as well as quality of data collected and acceptance of supportive supervision amongst stakeholders involved. It also ensured better availability of evidence for follow-up actions, including budgeting and planning, and higher stakeholder motivation and ownership of subsequent quality improvement measures. The new approach reduced time and cost spent during supportive supervision. This increased feasibility of supportive supervision and hence the likelihood of its implementation. Thus, the results presented together with previous findings suggested that if used as the standard approach for routine supportive supervision the new approach offers a suitable option to make supportive supervision more efficient and effective and therewith more sustainable. Moreover, the new approach also provides informed guidance to overcome several problems of supportive supervision and healthcare quality assessments in low- and middle income countries.
The ability of micro-organisms to degrade isosaccharinic acids (ISAs) while tolerating hyperalkaline conditions is pivotal to our understanding of the biogeochemistry associatedwithin these environs, but also in scenarios pertaining to the cementitious disposal of radioactivewastes. An alkalitolerant, ISA degradingmicro-organismwas isolated fromthe hyperalkaline soils resulting fromlime depositions. Here, we report the first whole-genome sequence, ISA degradation profile and carbohydrate preoteome of a Macellibacteroides fermentans strain HH-ZS, 4.08Mb in size, coding 3,241 proteins, 64 tRNA, and 1 rRNA.
The ability of biofilms to form on a range of materials (cementious backfill (Nirex Reference Vault Backfill (NRVB)), graphite, and stainless steel) relevant to potential UK intermediate level radioactive waste (ILW) disposal concepts was investigated by exposing these surfaces to alkaliphilic flocs generated by mature biofilm communities. Flocs are aggregates of biofilm material that are able to act as a transport vector for the propagation of biofilms. In systems where biofilm formation was observed there was also a decrease in the sorption of isosaccharinic acids to the NRVB. The biofilms were composed of cells, extracellular DNA (eDNA), proteins, and lipids with a smaller polysaccharide fraction, which was biased towards mannopyranosyl linked carbohydrates. The same trend was seen with the graphite and stainless steel surfaces at these pH values, but in this case the biofilms associated with the stainless steel surfaces had a distinct eDNA basal layer that anchored the biofilm to the surface. At pH 13, no structured biofilm was observed, rather all the surfaces accumulated an indistinct organic layer composed of biofilm materials. This was particularly the case for the stainless steel coupons which accumulated relatively large quantities of eDNA. The results demonstrate that there is the potential for biofilm formation in an ILW-GDF provided an initiation source for the microbial biofilm is present. They also suggest that even when conditions are too harsh for biofilm formation, exposed surfaces may accumulate organic material such as eDNA.
The survival of microorganisms within a cementitious geological disposal facility for radioactive wastes heavily depends on their ability to survive the calcium-dominated, hyperalkaline conditions resulting from the dissolution of the cementitious materials. The results from this study show that the formation of flocs, composed of a complex mixture of extracellular polymeric substances (EPS), provides protection against alkaline pH values up to 13.0. The flocs were dominated by Alishewanella and Dietzia spp., producing a mannose-rich carbohydrate fraction incorporating extracellular DNA, resulting in Ca2+ sequestration. EPS provided a ∼10-μm thick layer around the cells within the center of the flocs, which were capable of growth at pH values of 11.0 and 11.5, maintaining internal pH values of 10.4 and 10.7, respectively. Microorganisms survived at a pH of 12.0, where an internal floc pH of 11.6 was observed, as was a reduced associated biomass. We observed limited floc survival (<2 weeks) at a pH of 13.0. This study demonstrates that flocs maintain lower internal pHs in response to the hyperalkaline conditions expected to occur within a cementitious geological disposal facility for radioactive wastes and indicates that floc communities within such a facility can survive at pHs up to 12.0.IMPORTANCE The role of extracellular polymeric substances (EPS) in the survival of microorganisms in hyperalkaline conditions is poorly understood. Here, we present the taxonomy, morphology, and chemical characteristics of an EPS-based microbial floc, formed by a consortium isolated from an anthropogenic hyperalkaline site. Short-term (<2 weeks) survival of the flocs at a pH of 13 was observed, with indefinite survival observed at a pH of 12.0. Measurements from micro-pH electrodes (10-μm-diameter tip) demonstrated that flocs maintain lower internal pHs in response to hyperalkaline conditions (pH 11.0, 11.5, and 12.0), demonstrating that floc formation and EPS production are survival strategies under hyperalkaline conditions. The results indicate how microbial communities may survive and propagate within the hyperalkaline environment that is expected to prevail in a cementitious geological disposal facility for radioactive wastes; the results are also relevant to the wider extremophile community.
Diasteriomeric isosaccharinic acid (ISA) is an important consideration within safety assessments for the disposal of the United Kingdoms' nuclear waste legacy, where it may potentially influence radionuclide migration. Since the intrusion of micro-organisms may occur within a disposal concept, the impact of ISA may be impacted by microbial metabolism. Within the present study we have established two polymicrobial consortia derived from a hyperalkaline soil. Here, α-ISA and a diatereomeric mix of ISAs' were used as a sole carbon source, reflecting two common substrates appearing within the literature. The metabolism of ISA within these two consortia was similar, where ISA degradation resulted in the acetogenesis and hydrogenotrophic methanogenesis. The chemical data obtained confirm that the diastereomeric nature of ISA is likely to have no impact on its metabolism within alkaline environments. High throughput sequencing of the original soil showed a diverse community which, in the presence of ISA allowed for the dominance the Clostridiales associated taxa with Clostridium clariflavum prevalent. Further taxonomic investigation at the genus level showed that there was in fact a significant difference (p = 0.004) between the two community profiles. Our study demonstrates that the selection of carbon substrate is likely to have a significant impact on microbial community composition estimations, which may have implications with respect to a safety assessment of an ILW-GDF.
Anthropogenic hyperalkaline sites provide an environment that is analogous to proposed cementitious geological disposal facilities (GDF) for radioactive waste. Under anoxic, alkaline conditions cellulosic wastes will hydrolyze to a range of cellulose degradation products (CDP) dominated by isosaccharinic acids (ISA). In order to investigate the potential for microbial activity in a cementitious GDF, cellulose samples were incubated in the alkaline (∼pH 12), anaerobic zone of a lime kiln waste site. Following retrieval, these samples had undergone partial alkaline hydrolysis and were colonized by a Clostridia-dominated biofilm community, where hydrogenotrophic, alkaliphilic methanogens were also present. When these samples were used to establish an alkaline CDP fed microcosm, the community shifted away from Clostridia, methanogens became undetectable and a flocculate community dominated by Alishewanella sp. established. These flocs were composed of bacteria embedded in polysaccharides and proteins stabilized by extracellular DNA. This community was able to degrade all forms of ISA with >60% of the carbon flow being channelled into extracellular polymeric substance (EPS) production. This study demonstrated that alkaliphilic microbial communities can degrade the CDP associated with some radioactive waste disposal concepts at pH 11. These communities divert significant amounts of degradable carbon to EPS formation, suggesting that EPS has a central role in the protection of these communities from hyperalkaline conditions.
The contamination of surface environments with hydroxide rich wastes leads to the formation of high pH (>11.0) soil profiles. One such site is a legacy lime works at Harpur Hill, Derbyshire where soil profile indicated in-situ pH values up to pH 12. Soil and porewater profiles around the site indicated clear evidence of the presence of the α and β stereoisomers of isosaccharinic acid (ISA) resulting from the anoxic, alkaline degradation of cellulosic material. ISAs are of particular interest with regards to the disposal of cellulosic materials contained within the intermediate level waste (ILW) inventory of the United Kingdom, where they may influence radionuclide mobility via complexation events occurring within a geological disposal facility (GDF) concept. The mixing of uncontaminated soils with the alkaline leachate of the site resulted in ISA generation, where the rate of generation in-situ is likely to be dependent upon the prevailing temperature of the soil. Microbial consortia present in the uncontaminated soil were capable of surviving conditions imposed by the alkaline leachate and demonstrated the ability to utilise ISAs as a carbon source. Leachate-contaminated soil was sub-cultured in a cellulose degradation product driven microcosm operating at pH 11, the consortia present were capable of the degradation of ISAs and the generation of methane from the resultant H2/CO2 produced from fermentation processes. Following microbial community analysis, fermentation processes appear to be predominated by Clostridia from the genus Alkaliphilus sp, with methanogenesis being attributed to Methanobacterium and Methanomassiliicoccus sp. The study is the first to identify the generation of ISA within an anthropogenic environment and advocates the notion that microbial activity within an ILW-GDF is likely to influence the impact of ISAs upon radionuclide migration.
One design concept for the long-term management of the UK's intermediate level radioactive wastes (ILW) is disposal to a cementitious geological disposal facility (GDF). Under the alkaline (10.013.0) anoxic conditions expected within a GDF, cellulosic wastes will undergo chemical hydrolysis. The resulting cellulose degradation products (CDP) are dominated by α- and β-isosaccharinic acids (ISA), which present an organic carbon source that may enable subsequent microbial colonisation of a GDF. Microcosms established from neutral, near-surface sediments demonstrated complete ISA degradation under methanogenic conditions up to pH 10.0. Degradation decreased as pH increased, with β-ISA fermentation more heavily influenced than α-ISA. This reduction in degradation rate was accompanied by a shift in microbial population away from organisms related to Clostridium sporosphaeroides to a more diverse Clostridial community. The increase in pH to 10.0 saw an increase in detection of Alcaligenes aquatilis and a dominance of hydrogenotrophic methanogens within the Archaeal population. Methane was generated up to pH 10.0 with acetate accumulation at higher pH values reflecting a reduced detection of acetoclastic methanogens. An increase in pH to 11.0 resulted in the accumulation of ISA, the absence of methanogenesis and the loss of biomass from the system. This study is the first to demonstrate methanogenesis from ISA by near surface microbial communities not previously exposed to these compounds up to and including pH 10.0.
Objective The expression of FcγRIIIa/CD16 may render monocytes targets for activation by IgG-containing immune complexes (IC). We investigated whether FcγRIIIa/CD16 was upregulated in rheumatoid arthritis (RA), associated with TNF production in response to IC-stimulation, and if this predicted response to methotrexate therapy. Methods FcγRIIIa/CD16 expression on CD14low and CD14++ monocytes was measured by flow cytometry in healthy controls and RA patients (early and long-standing disease). Intracellular TNF-staining was carried out after in vitro LPS or heat-aggregated immunoglobulin (HAG) activation. FcγRIIIa/CD16 expression pre- and post-steroid/methotrexate treatment was examined. Results Increased FcγRIIIa/CD16 expression on CD14++ monocytes in long-standing RA patients compared to controls was demonstrated (p = 0.002) with intermediate levels in early-RA patients. HAG-induced TNF-production in RA patients was correlated with the percentage of CD14++ monocytes expressing FcγRIIIa/CD16 (p<0.001). The percentage of CD14++ monocytes expressing FcγRIIIa/CD16 at baseline in early DMARD-naïve RA patients was negatively correlated with DAS28-ESR improvement 14-weeks post-methotrexate therapy (p = 0.003) and was significantly increased in EULAR non-responders compared to moderate (p = 0.01) or good responders (p = 0.003). FcγRIIIa/CD16 expression was not correlated with age, presence of systemic inflammation or autoantibody titers. Conclusion Increased FcγRIIIa/CD16 expression on CD14++ monocytes in RA may result in a cell that has increased responsiveness to IC-stimulation. This monocyte subset may contribute to non-response to methotrexate therapy.