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1.
Nutrients ; 16(7)2024 Apr 02.
Article in English | MEDLINE | ID: mdl-38613067

ABSTRACT

Students are required to complete supervised practice hours prior to becoming Registered Dietitians and Physician Assistants. Research suggests that environmental and social factors affect dietetic interns' diets during their internship, although these factors have not been studied among physician assistant interns. This cross-sectional study utilized an online survey to compare dietetic interns' (n = 81) and physician assistant interns' (n = 79) fruit and vegetable intake, food security, barriers to healthy eating, and empowerment for making healthy dietary choices during an internship. Differences were assessed via independent t-tests and chi-square distributions. The significance was set at p < 0.05. Dietetic interns had a higher vegetable intake (p = 0.002) while physician assistant interns had higher rates of food insecurity (p = 0.040). Dietetic interns reported a greater impact on their dietary choices due to mental fatigue (p = 0.006), while physician assistant interns' dietary choices were more heavily impacted by peer influence, interactions with patients, and interactions with preceptors (p < 0.05). There was not a group difference in overall empowerment (p = 0.157), although both groups rated empowerment for asking for help with food and nutrition challenges the lowest of the empowerment sub-items. Addressing interns' unique needs may support students' educational success and wellbeing once they are professionals, promote a diverse workforce, and ensure optimal care for patients.


Subject(s)
Dietetics , Physician Assistants , Humans , Fruit , Diet, Healthy , Cross-Sectional Studies , Pilot Projects , Vegetables , Food Security
2.
Aust J Rural Health ; 31(5): 839-854, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37485742

ABSTRACT

BACKGROUND: The Australian geographically rural and remote disability workforce has historically demonstrated difficulties to keep up with the demand for quality services and supports for people with disability. In 2013, the National Disability Insurance Scheme (NDIS) was launched to provide individualised disability support packages to meet people's needs. To receive funding, people with disability are required to develop a NDIS plan. That plan is then funded by the National Disability Insurance Agency (NDIA), the government agency responsible for managing the NDIS. Although the NDIS has been operating for almost 10 years, there is limited research into the planning experiences of the workforce in regional, rural and remote regions of Australia. This review aims to ascertain the level of scholarly investigation into workers' experiences of NDIS planning. METHODOLOGY: Research publication databases were searched using a specific search string to identify publications that included reference to the workforce's experiences of the NDIS planning process in regional, rural and remote regions of Australia. The Mixed Methods Appraisal Tool (MMAT) was adopted to appraise the quality of the research publications. Research publications that focused on those working with Aboriginal and Torres Strait Islander people were also appraised using the Aboriginal and Torres Strait Islander Quality Appraisal Tool developed by the Centre for Excellence in Aboriginal Chronic Disease Knowledge Translation and Exchange. A thematic synthesis of the publications was undertaken to ascertain disability and health workforce experiences of the NDIS planning process. RESULTS: Seven papers met the selection criteria. Two papers were policy reviews and reported the improvements of the NDIS planning process since its inception. These studies reported four reoccurring themes: (1) cultural/socioeconomic and geographical factors; (2) administrative burden and bureaucracy; (3) values, culture and geography; and (4) burden on allied health workers. CONCLUSION: The NDIS planning process has developed and progressed since its rollout in 2013. There are limited research papers available that describe the workforce's experience of the planning process in regional, rural and remote regions. More research in this area is needed to identify the experiences of the disability workforce in relation to the NDIS planning process.


Subject(s)
Disabled Persons , Health Services, Indigenous , Insurance, Disability , Humans , Australia , Population Groups , Workforce
3.
Aust J Rural Health ; 31(4): 631-647, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37367630

ABSTRACT

BACKGROUND: Australia's National Disability Insurance Scheme (NDIS) was launched in 2013 to provide financial support packages for people with disability to purchase supports and services to enhance independence. People with disability are required to develop a plan with the National Disability Insurance Agency (NDIA), the government department responsible for managing the NDIS. This scoping review aims to ascertain the level of research into people's experience of the NDIS planning process in these geographic areas. METHODOLOGY: Research publication databases were searched using a specific search string to identify research about people with disability and their families/carer's experiences of the NDIS planning process in regional, rural and remote regions of Australia. The Mixed Methods Appraisal Tool (MMAT) was adopted to appraise the quality of the research publications. Research publications focused on Aboriginal and Torres Strait Islander people were additionally appraised using the Aboriginal and Torres Strait Islander Quality Appraisal Tool developed by the Centre for Excellence in Aboriginal Chronic Disease Knowledge Translation and Exchange. A thematic synthesis of the publications' contents was undertaken to ascertain people with disabilities and carers experience of the NDIS planning process. RESULTS: Ten (N = 10) research papers were found that met the inclusion criteria. Two papers were policy reviews and reported on the improvements of the NDIS planning process since its conception. The analysis found the research archive focused on five themes: (1) healthcare workforce and NDIA staff; (2) NDIS package holders and carers lack of awareness of the NDIS; (3) cultural/socio-economic barriers; (4) travel funding; and (5) emotional burden of the NDIS planning process. CONCLUSION: There are limited papers available that explore people's experiences of the NDIS planning process in regional, rural and remote regions of Australia. This systematic review illuminates the difficulties, barriers and concerns of people with disability and their carers about the planning process.


Subject(s)
Disabled Persons , Health Services, Indigenous , Insurance, Disability , Humans , Caregivers , Australia , Indigenous Peoples
4.
Vet Comp Oncol ; 20(4): 881-889, 2022 Dec.
Article in English | MEDLINE | ID: mdl-35856268

ABSTRACT

Histopathological evaluation of tumours is a subjective process, but studies of inter-pathologist agreement are uncommon in veterinary medicine. The Comparative Brain Tumour Consortium (CBTC) recently published diagnostic criteria for canine gliomas. Our objective was to assess the degree of inter-pathologist agreement on intracranial canine gliomas, utilising the CBTC diagnostic criteria in a cohort of eighty-five samples from dogs with an archival diagnosis of intracranial glioma. Five pathologists independently reviewed H&E and immunohistochemistry sections and provided a diagnosis and grade. Percentage agreement and kappa statistics were calculated to measure inter-pathologist agreement between pairs and amongst the entire group. A consensus diagnosis of glioma subtype and grade was achieved for 71/85 (84%) cases. For these cases, percentage agreement on combined diagnosis (subtype and grade), subtype only and grade only were 66%, 80% and 82%, respectively. Kappa statistics for the same were 0.466, 0.542 and 0.516, respectively. Kappa statistics for oligodendroglioma, astrocytoma and undefined glioma were 0.585, 0.566 and 0.280 and were 0.516 for both low-grade and high-grade tumours. Kappa statistics amongst pairs of pathologists for combined diagnosis varied from 0.352 to 0.839. 8 % of archival oligodendrogliomas and 61% of archival astrocytomas were reclassified as another entity after review. Inter-pathologist agreement utilising CBTC guidelines for canine glioma was moderate overall but varied from fair to almost perfect between pairs of pathologists. Agreement was similar for oligodendrogliomas and astrocytomas but lower for undefined gliomas. These results are similar to pathologist agreement in human glioma studies and with other tumour entities in veterinary medicine.


Subject(s)
Astrocytoma , Brain Neoplasms , Dog Diseases , Glioma , Oligodendroglioma , Humans , Animals , Dogs , Oligodendroglioma/diagnosis , Oligodendroglioma/veterinary , Oligodendroglioma/pathology , Pathologists , Dog Diseases/diagnosis , Dog Diseases/pathology , Glioma/diagnosis , Glioma/veterinary , Glioma/pathology , Astrocytoma/veterinary , Brain Neoplasms/diagnosis , Brain Neoplasms/veterinary , Brain Neoplasms/pathology
5.
Rural Remote Health ; 22(2): 7011, 2022 05.
Article in English | MEDLINE | ID: mdl-35570381

ABSTRACT

Policymakers, funding bodies and service provider agencies require objective indicators to ensure quality, equity and access. We sought to depict the availability of rural and remote allied health and disability services in Queensland using one such indicator (spatial analysis) to explore concepts related to 'thin' markets, including market sufficiency and market diversity. Our findings suggested, counter-intuitively, that more remote settings had greater disability service sufficiency and diversity than larger regional centres. While on careful interpretation this face-value observation can be rationalised, it can also be used to influence decision making to the detriment of remote area consumers and communities. Most importantly, it does not adequately incorporate consumer, community and service provider realities in remote areas. This led us to consider additional factors that should routinely be acknowledged to broaden planning for disability services in rural and remote settings. We suggest a number of additional considerations that should also inform policy, funding and service planning decisions. The challenge facing all stakeholders is to develop new indicators that are meaningfully reflective of the realities of rural and remote consumers, families, communities and service providers, as well as market realities.


Subject(s)
Disabled Persons , Rural Health Services , Humans , Queensland , Rural Population , Spatial Analysis
6.
Vet Pathol ; 58(5): 952-963, 2021 09.
Article in English | MEDLINE | ID: mdl-34196247

ABSTRACT

Evasion of the immune response is an integral part of the pathogenesis of glioma. In humans, important mechanisms of immune evasion include recruitment of regulatory T cells (Tregs) and polarization of macrophages toward an M2 phenotype. Canine glioma has a robust immune cell infiltrate that has not been extensively characterized. The purpose of this study was to determine the distribution of immune cells infiltrating spontaneous intracranial canine gliomas. Seventy-three formalin-fixed, paraffin-embedded tumor samples were evaluated using immunohistochemistry for CD3, forkhead box 3 (FOXP3), CD20, Iba1, calprotectin (Mac387), CD163, and indoleamine 2,3-dioxygenase (IDO). Immune cell infiltration was present in all tumors. Low-grade and high-grade gliomas significantly differed in the numbers of FoxP3+ cells, Mac387+ cells, and CD163+ cells (P = .006, .01, and .01, respectively). Considering all tumors, there was a significant increase in tumor area fraction of CD163 compared to Mac387 (P < .0001), and this ratio was greater in high-grade tumors than in low-grade tumors (P = .005). These data warrant further exploration into the roles of macrophage repolarization or Treg interference therapy in canine glioma.


Subject(s)
Dog Diseases , Glioma , Animals , Antigens, CD20 , Dogs , Glioma/veterinary , Immunohistochemistry , Lymphocytes, Tumor-Infiltrating , T-Lymphocytes, Regulatory
7.
Disabil Rehabil ; 43(20): 2919-2929, 2021 10.
Article in English | MEDLINE | ID: mdl-32088974

ABSTRACT

PURPOSE: This two-year (2016-2018) study aimed to identify what a good life is for Aboriginal people with disability in remote Central Australia and how service providers can support them to achieve a good life. This paper presents the findings that relate to barriers to delivering services for Aboriginal people with disability. METHODS: In-depth interviews and focus groups were held with Aboriginal people with disability and their carers aged at least 18 years from the Ngaanyatjarra Pitjantjatjara Yankunytjatjara (NPY) Lands and community organisations providing services there. The data were analysed using thematic analysis. RESULTS: There were 109 participants, of whom 47 were workers in service provider organisations and 62 were Aboriginal people. From the data, barriers to delivering services to support Aboriginal people to live a good life and solutions to overcome the barriers, were identified and described under the headings of environmental barriers and systemic issues. CONCLUSIONS: We discuss the policy implications of these findings with regard to addressing Indigenous disadvantage and how governments, service providers, communities, and Aboriginal people with disability and their families can work in partnership to address these barriers.Implications for RehabilitationIndigenous people with disability living in remote and very remote communities experience significant access and equity barriers to culturally responsive services that enable them to live a socially and culturally engaged life.Localised government and service provider disability policy approaches in Indigenous communities need to focus on both environmental and systemic issues.Greater investment in local remote communities is required to build the capacity of Indigenous families to support Aboriginal people with a disability to live a culturally and socially included life.


Subject(s)
Disabled Persons , Health Services, Indigenous , Adolescent , Adult , Australia , Caregivers , Humans , Native Hawaiian or Other Pacific Islander
8.
Toxicol Pathol ; 48(2): 317-322, 2020 02.
Article in English | MEDLINE | ID: mdl-31801420

ABSTRACT

Reticulum cell hyperplasia (RCH) was a term used for many years by the National Toxicology Program (NTP) to describe a certain non-neoplastic bone marrow lesion of rats. Retrospective microscopic evaluation of RCH lesions and immunohistochemistry analyses were performed to reassess and further characterize these lesions. The NTP database was searched to identify femoral bone marrow specimens diagnosed with RCH from 1981 to 2014 (n = 254). The diagnosis last occurred in 2003, after which the term "cellular infiltration" was used. Eighty-three RCH slides, spanning 22 years, representing 34 different chemicals, were selected for microscopic review, and a subset (23) was chosen for ionized calcium binding adapter molecule 1 (Iba1) immunohistochemical staining; initial investigations revealed Iba1 worked as a macrophage marker on decalcified tissue. The following diagnoses were made upon reevaluation: 36 were consistent with cellularity increased, macrophage, 22 with histiocytic sarcoma, 8 with increased myeloid cells, 4 with autolysis, and 13 were normal appearance. All 23 RCH lesions stained positive for Iba1. Fifty-eight of 83 bone marrows previously diagnosed with RCH are consistent morphologically and immunohistochemically with cells of histiocytic origin. These results will help with interpretation of historical data and demonstrates that Iba1 can be used in decalcified bone marrow sections.


Subject(s)
Biomarkers/analysis , Bone Marrow Cells/pathology , Macrophages/metabolism , Animals , Bone Marrow Cells/metabolism , Calcium-Binding Proteins/biosynthesis , Coloring Agents , Female , Hyperplasia/pathology , Immunohistochemistry , Microfilament Proteins/biosynthesis , Monocytes/metabolism , Rats , Rats, Sprague-Dawley , Retrospective Studies , Specimen Handling/methods
9.
Toxicol Pathol ; 47(5): 577-584, 2019 07.
Article in English | MEDLINE | ID: mdl-31064278

ABSTRACT

The majority of the tumors in the gastrointestinal (GI) tract of rats and mice, with spindle cell morphology, are diagnosed as smooth muscle tumors (SMTs). Similarly, several decades ago human GI tumors with spindle cell morphology were also diagnosed as SMTs. However, later investigations identified most of these tumors in humans as gastrointestinal stromal tumors (GISTs). The GISTs are considered to arise from the interstitial cells of Cajal located throughout the GI tract. Positive immunohistochemical staining with CKIT antibody is a well-accepted diagnostic marker for GISTs in humans. Since there is a considerable overlap between the histomorphology of SMTs and GISTs, it is not possible to distinguish them on hematoxylin and eosin stained sections. As a result, GISTs are not routinely diagnosed in toxicological studies. The current study was designed to evaluate the tumors diagnosed as leiomyoma or leiomyosarcoma in the National Toxicology Program's 2-year bioassays using CKIT, smooth muscle actin, and desmin immunohistochemistry. The results demonstrate that most of the mouse SMTs diagnosed as leiomyoma or leiomyosarcoma are likely GISTs, whereas in rats the tumors are likely SMTs and not GISTs.


Subject(s)
Gastrointestinal Neoplasms/pathology , Gastrointestinal Stromal Tumors/pathology , Gastrointestinal Tract/pathology , Smooth Muscle Tumor/pathology , Animals , Databases, Factual , Female , Gastrointestinal Neoplasms/genetics , Gastrointestinal Stromal Tumors/genetics , Immunohistochemistry , Leiomyoma/genetics , Leiomyoma/pathology , Leiomyosarcoma/genetics , Leiomyosarcoma/pathology , Male , Mice , Proto-Oncogene Proteins c-kit/genetics , Rats , Smooth Muscle Tumor/genetics , Species Specificity , Toxicity Tests
10.
Toxicol Pathol ; 46(6): 653-659, 2018 08.
Article in English | MEDLINE | ID: mdl-30089414

ABSTRACT

The use of three-dimensional (3-D) in vitro culture systems (spheroids, organoids) in biomolecular and drug discovery research has become increasingly popular. The popularity is due, in part, to a diminished reliance on animal bioassays and a desire to develop physiologically relevant cell culture systems that simulate the in vivo tissue microenvironment. Most evaluations of 3-D cultures are by confocal microscopy and high-content imaging; however, these technologies do not allow for detailed cellular morphologic assessments or permit basic hematoxylin and eosin histologic evaluations. There are few studies that have reported detailed processes for preparing 3-D cultures for paraffin embedding and subsequent use for histochemical or immunohistochemical staining. In an attempt to do so, we have developed a protocol to paraffin-embed human liver spheroids that can be sectioned with a microtome and mounted onto glass slides for routine histochemical and immunohistochemical staining and light microscopic evaluations.


Subject(s)
Cell Culture Techniques/methods , Immunohistochemistry/methods , Liver/cytology , Microscopy , Spheroids, Cellular/ultrastructure , Cell Culture Techniques/instrumentation , Cell Line, Tumor , Humans , Immunohistochemistry/instrumentation , Paraffin Embedding , Staining and Labeling
11.
Toxicol Pathol ; 46(5): 488-510, 2018 07.
Article in English | MEDLINE | ID: mdl-29966501

ABSTRACT

Immunohistochemistry (IHC) is a valuable tool in pathology. This review provides a brief description of the technical aspects of IHC and a detailed discussion on the variables that affect the results, interpretation, and reproducibility of IHC results. Lists of antibodies that have and have not worked in IHC on various mouse and rat tissues in our laboratory are provided as a guidance for selection of antibodies. An approach to IHC method optimization is presented. Finally, the critical information that should be included as a part of peer-reviewed manuscript is also discussed.


Subject(s)
Clinical Laboratory Techniques/methods , Immunohistochemistry/methods , Pathology/methods , Toxicology/methods , Animals , Antibodies/chemistry , Humans , Mice , Rats , Reproducibility of Results , Tissue Fixation
12.
Sci Rep ; 7(1): 13030, 2017 10 12.
Article in English | MEDLINE | ID: mdl-29026162

ABSTRACT

Expression of membrane proteins often leads to growth inhibition and perturbs central metabolism and this burden varies with the protein being overexpressed. There are also known strain backgrounds that allow greater expression of membrane proteins but that differ in efficacy across proteins. We hypothesized that for any membrane protein, it may be possible to identify a modified strain background where its expression can be accommodated with less burden. To directly test this hypothesis, we used a bar-coded transposon insertion library in tandem with cell sorting to assess genome-wide impact of gene deletions on membrane protein expression. The expression of five membrane proteins (CyoB, CydB, MdlB, YidC, and LepI) and one soluble protein (GST), each fused to GFP, was examined. We identified Escherichia coli mutants that demonstrated increased membrane protein expression relative to that in wild type. For two of the proteins (CyoB and CydB), we conducted functional assays to confirm that the increase in protein expression also led to phenotypic improvement in function. This study represents a systematic approach to broadly identify genetic loci that can be used to improve membrane protein expression, and our method can be used to improve expression of any protein that poses a cellular burden.


Subject(s)
Gene Editing , Membrane Proteins/metabolism , DNA Transposable Elements/genetics , Escherichia coli/genetics , Gene Deletion , Gene Library , Green Fluorescent Proteins/metabolism , Mutagenesis, Insertional/genetics , Reproducibility of Results
13.
JCI Insight ; 2(16)2017 Aug 17.
Article in English | MEDLINE | ID: mdl-28814662

ABSTRACT

The pathogenesis of primary Sjogren's syndrome (SS), an autoimmune disease that targets the mucosa of exocrine tissues, is poorly understood. Although several mouse models have been developed that display features of SS, most of these are within the larger context of a lupus-like presentation. Immunity-related GTPase family M protein 1 (Irgm1) is an interferon-inducible cytoplasmic GTPase that is reported to regulate autophagy and mitochondrial homeostasis. Here, we report that naive Irgm1-/- mice display lymphocytic infiltration of multiple mucosal tissues including the lung in a manner reminiscent of SS, together with IgA class-predominant autoantibodies including anti-Ro and anti-La. This phenotype persists in the germ-free state, but is abolished by deletion of Irgm3. Irgm1-/- mice have increased local production in the lung of TECP15-idiotype IgA, a natural antibody with dual reactivity against host and pneumococcal phosphorylcholine. Associated with this, Irgm1-/- mice display enhanced opsonization and clearance of Streptococcus pneumoniae from the lung and increased survival from pneumococcal pneumonia. Taken together, our results identify Irgm1 as a master regulator of mucosal immunity that dually modulates evolutionarily conserved self- and other-directed immune responses at the interface of host with environment.

14.
Australas J Ageing ; 36(2): 128-133, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28635093

ABSTRACT

OBJECTIVE: To explore the role art centres in remote communities play for Aboriginal and Torres Strait Islander Australians living with dementia. METHODS: A comprehensive literature search was undertaken, with no restrictions on articles regarding year of publication. RESULTS: Art programmes have been found to be of benefit to both people living with dementia and their carers, particularly when programmes are administered in environments that are culturally revered. Findings indicate remote art centres play a key role in maintaining traditions, culture and practices unique to Aboriginal and Torres Strait Islanders, but there is a gap in knowledge regarding how they cater for the needs of people with dementia. CONCLUSION: Addressing this gap will be helpful in remote areas where prevalence of dementia is up to five times that of non-Aboriginal people, and there are limited health and support services. Further research is required to explore strengths and gaps of current practices.


Subject(s)
Art , Dementia/therapy , Health Services, Indigenous , Australia , Humans , Native Hawaiian or Other Pacific Islander
15.
ACS Synth Biol ; 5(7): 679-88, 2016 07 15.
Article in English | MEDLINE | ID: mdl-27000939

ABSTRACT

Introducing extracellular electron transfer pathways into heterologous organisms offers the opportunity to explore fundamental biogeochemical processes and to biologically alter redox states of exogenous metals for various applications. While expression of the MtrCAB electron nanoconduit from Shewanella oneidensis MR-1 permits extracellular electron transfer in Escherichia coli, the low electron flux and absence of growth in these cells limits their practicality for such applications. Here we investigate how the rate of electron transfer to extracellular Fe(III) and cell survival in engineered E. coli are affected by mimicking different features of the S. oneidensis pathway: the number of electron nanoconduits, the link between the quinol pool and MtrA, and the presence of flavin-dependent electron transfer. While increasing the number of pathways does not significantly improve the extracellular electron transfer rate or cell survival, using the native inner membrane component, CymA, significantly improves the reduction rate of extracellular acceptors and increases cell viability. Strikingly, introducing both CymA and riboflavin to Mtr-expressing E. coli also allowed these cells to couple metal reduction to growth, which is the first time an increase in biomass of an engineered E. coli has been observed under Fe2O3 (s) reducing conditions. Overall, this work provides engineered E. coli strains for modulating extracellular metal reduction and elucidates critical factors for engineering extracellular electron transfer in heterologous organisms.


Subject(s)
ATP-Binding Cassette Transporters/metabolism , Bacterial Proteins/metabolism , Cytochrome c Group/metabolism , Escherichia coli/metabolism , Genetic Engineering/methods , Riboflavin/pharmacology , ATP-Binding Cassette Transporters/genetics , Bacterial Proteins/genetics , Cytochrome c Group/genetics , Electron Transport , Escherichia coli/drug effects , Escherichia coli/genetics , Escherichia coli/growth & development , Ferric Compounds/metabolism , Flavins/metabolism , Flavins/pharmacology , Gene Expression Regulation, Bacterial , Iron/metabolism , Oxidation-Reduction , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Riboflavin/metabolism , Shewanella/genetics , Shewanella/metabolism
16.
Aust Occup Ther J ; 62(5): E126, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26726327

ABSTRACT

This letter was sent to the Honourable Helen Morton by Emma Campbell after the Occupational Therapy Australia National Conference. A number of members of First Australian and Australian OTs online were keen to show their support for Emma's letter and share this with other OT colleagues.


Subject(s)
Cultural Competency , Health Status Disparities , Native Hawaiian or Other Pacific Islander , Occupational Therapy , Politics , Australia , Humans
17.
mBio ; 5(6): e01932, 2014 Nov 04.
Article in English | MEDLINE | ID: mdl-25370492

ABSTRACT

UNLABELLED: Engineering microbial hosts for the production of fungible fuels requires mitigation of limitations posed on the production capacity. One such limitation arises from the inherent toxicity of solvent-like biofuel compounds to production strains, such as Escherichia coli. Here we show the importance of host engineering for the production of short-chain alcohols by studying the overexpression of genes upregulated in response to exogenous isopentenol. Using systems biology data, we selected 40 genes that were upregulated following isopentenol exposure and subsequently overexpressed them in E. coli. Overexpression of several of these candidates improved tolerance to exogenously added isopentenol. Genes conferring isopentenol tolerance phenotypes belonged to diverse functional groups, such as oxidative stress response (soxS, fpr, and nrdH), general stress response (metR, yqhD, and gidB), heat shock-related response (ibpA), and transport (mdlB). To determine if these genes could also improve isopentenol production, we coexpressed the tolerance-enhancing genes individually with an isopentenol production pathway. Our data show that expression of 6 of the 8 candidates improved the production of isopentenol in E. coli, with the methionine biosynthesis regulator MetR improving the titer for isopentenol production by 55%. Additionally, expression of MdlB, an ABC transporter, facilitated a 12% improvement in isopentenol production. To our knowledge, MdlB is the first example of a transporter that can be used to improve production of a short-chain alcohol and provides a valuable new avenue for host engineering in biogasoline production. IMPORTANCE: The use of microbial host platforms for the production of bulk commodities, such as chemicals and fuels, is now a focus of many biotechnology efforts. Many of these compounds are inherently toxic to the host microbe, which in turn places a limit on production despite efforts to optimize the bioconversion pathways. In order to achieve economically viable production levels, it is also necessary to engineer production strains with improved tolerance to these compounds. We demonstrate that microbial tolerance engineering using transcriptomics data can also identify targets that improve production. Our results include an exporter and a methionine biosynthesis regulator that improve isopentenol production, providing a starting point to further engineer the host for biogasoline production.


Subject(s)
Biofuels/toxicity , Drug Tolerance , Escherichia coli/genetics , Escherichia coli/metabolism , Metabolic Engineering , Escherichia coli/drug effects , Gene Expression Profiling , Gene Expression Regulation, Bacterial/drug effects , Molecular Sequence Data , Pentanols/metabolism , Pentanols/toxicity , Sequence Analysis, DNA
18.
ACS Synth Biol ; 2(3): 150-9, 2013 Mar 15.
Article in English | MEDLINE | ID: mdl-23656438

ABSTRACT

Introduction of the electron transfer complex MtrCAB from Shewanella oneidensis MR-1 into a heterologous host provides a modular and molecularly defined route for electrons to be transferred to an extracellular inorganic solid. However, an Escherichia coli strain expressing this pathway displayed limited control of MtrCAB expression and impaired cell growth. To overcome these limitations and to improve heterologous extracellular electron transfer, we used an E. coli host with a more tunable induction system and a panel of constitutive promoters to generate a library of strains that separately transcribe the mtr and cytochrome c maturation (ccm) operons over 3 orders of magnitude. From this library, we identified strains that show 2.2 times higher levels of MtrC and MtrA and that have improved cell growth. We find that a ~300-fold decrease in the efficiency of MtrC and MtrA synthesis with increasing mtr promoter activity critically limits the maximum expression level of MtrC and MtrA. We also tested the extracellular electron transfer capabilities of a subset of the strains using a three-electrode microbial electrochemical system. Interestingly, the strain with improved cell growth and fewer morphological changes generated the largest maximal current per cfu, rather than the strain with more MtrC and MtrA. This strain also showed ~30-fold greater maximal current per cfu than its ccm-only control strain. Thus, the conditions for optimal MtrCAB expression and anode reduction are distinct, and minimal perturbations to cell morphology are correlated with improved extracellular electron transfer in E. coli.


Subject(s)
Escherichia coli/genetics , Escherichia coli/metabolism , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Cytochromes c/genetics , Cytochromes c/metabolism , Electron Transport , Electrons , Operon , Promoter Regions, Genetic , Transcription, Genetic
19.
Am J Primatol ; 74(11): 1044-53, 2012 Nov.
Article in English | MEDLINE | ID: mdl-22865351

ABSTRACT

Endocrine data and characteristics of nonconceptive ovarian cycling and pregnancy are limited within the genus Callithrix to the common marmoset (C. jacchus) and Wied's black tufted-ear marmoset (C. kuhlii). This article presents patterns of urinary pregnanediol-3-glucuronide (PdG) excretion, as determined by enzyme immunoassay, throughout the course of ovarian cycling and pregnancy in white-faced marmosets (C. geoffroyi). Furthermore, characteristics of reproductive parameters including litter size, duration of gestation, maternal age, and information about ovarian cycling following administration of contraceptives are also described. A steep increase in PdG, an indication of ovulation, characterizes normative ovarian cycles, with peak-to-peak intervals between cycles being 27.82 ± 1.49 days in length. PdG excretion (µg/mg Cr) across pregnancy peaked during the 1st and 2nd trimesters (1st = 20.71 ± 2.98, 2nd = 21.16 ± 2.60) and declined gradually to near preconception levels over the 3rd trimester until parturition (3rd = 5.74 ± 1.60). Gestation lasted 148.55 ± 1.89 days. Most pregnancies (82.8%) resulted in an immediate postpartum ovulation (PPO) of 17.45 ± 2.22 days with 58.3% of PPOs resulting in conception. No differences in PdG excretion during the 1st trimester between full pregnancies and miscarriages were found, and pregnancy characteristics such as litter size, duration of gestation, and maternal age were not associated with PdG concentrations. Administration of cloprostenol resulted in shorter peak-to-peak cycle durations, but ovulation was detectable with similar concentrations of peak PdG to a normal nonconceptive cycle. Conversely, medroxyprogesterone acetate (DMPA) injections resulted in little to no PdG excretion across the ovarian cycle. Both methods of contraception providing effective prevention of conception. Overall, these results show that strong similarities in reproductive parameters persist within the genus Callithrix and to a lesser extent across the Callitrichidae family.


Subject(s)
Callithrix/physiology , Contraception , Estrous Cycle/physiology , Ovary/physiology , Pregnancy, Animal/physiology , Animals , Female , Postpartum Period/physiology , Pregnancy , Pregnanediol/analogs & derivatives , Pregnanediol/urine
20.
Foot Ankle Spec ; 4(6): 344-8, 2011 Dec.
Article in English | MEDLINE | ID: mdl-21965579

ABSTRACT

UNLABELLED: Frostbite can be a devastating and even debilitating injury. Early identification and proper treatment of frostbite is critical in saving digits and limbs. Tissue plasminogen activator (tPA) has been shown to be effective in reducing the number of digits amputated after severe frostbite injury. Nothing has been presented in the podiatric literature regarding the use of tPA in treating frostbite patients for preserving toes and feet. Intravenous tPA and IV heparin were used to treat severe frostbite injuries that did not show improvement after rapid rewarming, had absent Doppler pulses in the distal limb or digits, showed limited or no perfusion by Tc-99 3-phase bone scan, and had no contraindications to use of tPA. All 11 patients included in this study were treated at Hennepin County Medical Center between 2008 and 2010. A total of 73 digits (upper and lower extremity) were considered at risk for amputation after evaluation with Tc-99 bone scan. Of those digits that were affected, 43 were amputated. Intravenous tPA is a safe and effective treatment to reduce the number of digital amputations after severe frostbite injury. The authors' protocol for treating severe frostbite includes the use of tPA. LEVELS OF EVIDENCE: Therapeutic, Level IV.


Subject(s)
Fibrinolytic Agents/therapeutic use , Finger Injuries/therapy , Frostbite/therapy , Tissue Plasminogen Activator/therapeutic use , Toes/injuries , Adult , Amputation, Surgical , Fingers/blood supply , Fingers/diagnostic imaging , Fingers/surgery , Heparin/therapeutic use , Humans , Infusions, Intravenous , Middle Aged , Pulse , Radionuclide Imaging , Radiopharmaceuticals , Retrospective Studies , Severity of Illness Index , Technetium Tc 99m Sestamibi , Toes/blood supply , Toes/diagnostic imaging , Toes/surgery , Young Adult
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