1,725 research outputs found
Molecular Investigation of Heme Acquisition in Staphylococcus aureus
Staphylococcus aureus is a notorious, Gram-positive, coccoid-shaped bacterium that is pathogenic to humans and animals. It is the culprit of many infectious diseases ranging from boils, impetigo, and food poisoning to more serious diseases such as endocarditis, osteomyelitis,â and toxic shock syndrome. However, for S. aureus to survive in the host, nutrients and especially iron must be acquired. S. aureus expresses iron-regulated surface determinant (Isd) proteins that, together, function in the acquisition of heme iron. However, mutants devoid of IsdA or IsdE have only subtle defects in growth on heme as a sole iro» source. Here I demonstrate that an isd locus deletion mutant (Aisd) grows better than wildtype on heme-containing media, indicating the existence of non-isd mechanisms of heme acquisition. Transposon mutagenesis in the A isd background identified an insertion in brnQ3, encoding a putative branched chain amino acid (BCAA) transporter, which yielded a strain that grew extremely poorly, with an extended lag period, on media containing heme as a sole iron source. Expression of either brnQ3 or isdEF in trans, or exogenously supplying a mixture of Ile/Leu/Val/Thr complemented the growth deficiency of the mutant. In comparison to wildtype S. aureus, the isd brnQ3 mutant had impaired virulence in mice. Together, the data show not only that isdEF is active in heme uptake but also suggest tha\u27 brnQ3, despite the presence of two additional paralogs, is important for uptake of BCAAs, and that intracellular BCAAs, which are an indicator of nutritional status, regulate expression of an alternate, non-Isd, heme uptake mechanism in S. aureus
Patientsâ experiences of acute deterioration and Medical Emergency Team (MET) encounter : a grounded theory study
Globally, considerable effort has been made to ensure hospital patients whose clinical condition deteriorates receive timely and appropriate care. Research suggests that hospitals have increasing numbers of patients who are more likely to become seriously ill during their admission due to complex problems. Recently, patient experience has been recognised as a means of assessing healthcare delivery with healthcare services across the world gathering patient experience or satisfaction data. Acute deterioration is unique and complex for all involved. However, little is known about this experience from the patientâs perspective. The purpose of this study was to generate theory about processes patients engage in when experiencing acute deterioration and MET encounter. Also, the research aimed to recognise and explain the factors that mediate patientsâ experiences. The findings of this study contribute to a growing body of knowledge that will improve patient care and practice guidelines for healthcare professionals. Underpinned by the theoretical framework of symbolic interactionism, grounded theory was employed for this study. From it ontological, epistemological, and methodological underpinnings, constructivist grounded theory was considered the most suitable approach. Using purposive sampling, in-depth semi-structured interviews were conducted with 27 patients across three Australian healthcare services. Data were collected over a 12-month period, between May 2018 â May 2019 and analysed using constant comparative analysis. The theoretical model âUnravelling a complex experience: contextualising patientsâ experiences of acute clinical deterioration and Medical Emergency Team (MET) encounterâ emerged, offering a possible explanation of patientsâ actions and processes. Most patients began their journeys feeling something was wrong which triggered emotional changes (experiencing changes-before the encounter). Patient experience was influenced by a combination of physical and psychological changes and a MET response (perceiving the reality - the encounter). After the MET encounter, some patients searched for deeper understandings about their illnesses and the events that occurred, whereas others managed without further reflection (reflecting on the event-after the encounter). Contextual conditions emerged influencing patientsâ experiences with three broad mediating factors identified. Some participants identified that their acute deterioration and subsequent MET encounter was unexpected, and they perceived the nature of their illness (before their acute deterioration) as stable, based on what they had been told by medical staff (expectations and illness perception). Many participants acknowledged that their experience was dependent on the health care professionals who were caring for them at the time (relationship with the MET). Past experiences of illness and hospitalisation played an important role in participantsâ abilities to conceptualise their experiences of acute deterioration and MET encounter (past experiences). These factors exerted a significant influence on participantsâ experiences and helps to explain the differences between them. Unravelling a complex experience: Conceptualising patientsâ experiences of acute deterioration and MET encounter offers a possible explanation of patientsâ meanings, actions and processes when experiencing acute deterioration and MET encounter. The theory leads to recommendations that healthcare organisations gather data about patientsâ experiences of acute deterioration and MET encounters, as these provide insights and opportunity to identify challenges that can be addressed.. Findings provide an explanatory framework for similar phenomena and increase awareness of patientsâ experiences to ultimately inform health policy and improve patient care. The findings highlight the need for healthcare services to instigate strategies that support patients who have experienced acute deterioration. Further research could evaluate the effectiveness of implemented strategies.Doctor of Philosoph
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Nuclear matrix protein 2 antibody-positive adult dermatomyositis: a case report and review of the literature
Dermatomyositis is a clinically heterogenous inflammatory myopathy with unique cutaneous features. Myositis-specific antibodies can aid in diagnosis and anticipation of patient prognosis. Herein, we report a 22-year-old man who presented with multifocal erythematous plaques with violaceous papules on his bilateral elbows, neck, and face. He was diagnosed with biopsy-proven dermatomyositis and determined to be seropositive for nuclear matrix protein 2 antibody (NXP-2). He was treated with systemic corticosteroids, then intravenous methylprednisolone and azathioprine, and ultimately achieved greatest treatment response with intravenous immune globulin therapy
Linking hopping conductivity to giant dielectric permittivity in oxides
With the promise of electronics breakthrough, giant dielectric permittivity materials are under deep investigations. In most of the oxides where such behavior was observed, charged defects at interfaces are quoted for such giant behavior to occur but the underlying conduction and localization mechanisms are not well known. Comparing macroscopic dielectric relaxation to microscopic dynamics of charged defects resulting from electron paramagnetic resonance investigations we identify the actual charged defects in the case of BaTiO3 ceramics and composites. This link between the thermal activation at these two complementary scales may be extended to the numerous oxides were giant dielectric behavior was found
Evaluating emotional distress and health-related quality of life in patients with heart failure and their family caregivers:Testing dyadic dynamics using the Actor-Partner Interdependence Model
Purpose: 1) To compare levels of emotional symptoms and health-related quality of life between patients with heart failure and their family caregivers; and 2) to examine whether patientsâ and caregiversâ emotional symptoms were associated with their own, as well as their partnerâs health-related quality of life. Method: In this cross-sectional study, 41 patients-caregiver dyads (78% male patients, aged 68.6 years; and 83% female caregivers, aged 65.8 years) completed all nine dimensions of the Brief Symptom Inventory and the Minnesota Living with Heart failure Questionnaire. Dyadic data were analysed for 6 sub-scales of the Brief Symptom Inventory, using the ActorâPartner Interdependence Model. Results: There were no statistically significant differences in emotional symptoms and health-related quality of life between patients with heart failure and their caregivers. Patientsâ and caregiversâ emotional symptoms were associated with their own health-related quality of life. Caregiversâ anxiety, phobic anxiety, obsession-compulsion, depression and hostility negatively influenced their partnerâs (i.e. the patientâs) health-related quality of life. There were no partner effects of patientsâ emotional symptoms on the health-related quality of life of caregivers. Conclusions: The results of this study suggest that patients may be particularly vulnerable to the emotional distress, i.e. thoughts, impulses and actions of their caregivers. It may be possible to improve patientsâ health-related quality of life by targeting specific detrimental emotional symptoms of caregivers
PUBLIC ATTITUDES IN THE NORTHEAST REGION TOWARD RECOMBINANT PORCINE SOMATOTROPIN
This study explored the attitudes of consumers regarding the use of recombinant porcine somatotropin (PST) in the production of pork, and the association between the attitudes and individual socioeconomic characteristics. The data were collected from surveys of households located in the New York and Philadelphia metropolitan area. The results show that both gender and education may play a role in the level of concern regarding the use of PST. Education programs which address the safety of pork produced with PST need to target the lower-educated and female consumers. More-over, the education program should be developed by organizations which are trusted by the public, such as universities and public agencies.Food Consumption/Nutrition/Food Safety,
Romidepsin: evidence for its potential use to manage previously treated cutaneous T cell lymphoma
Advance Care Planning in Faith Communities: A Quality Improvement Project
This quality improvement project examined the impact of providing an advance care planning training tool to faith community nurses in the community setting on advance care planning knowledge, self-efficacy, and implementation of advance care planning outreach and advance directive completion. The pre- and post-intervention frequencies measure and paired-t test survey design resulted in clinically significant improvements in knowledge, and self-efficacy of advance care planning among faith community nurses. A fifty-fold increase was seen in advance care planning outreach activities among the group from pre- to post-intervention. The limitations of the project included small sample size and short implementation timing. However, the role of the faith community nurse in promoting and engaging in advance care planning to help communities move toward goal concordant care is clear
Tgif1 Counterbalances The Activity Of Core Pluripotency Factors In Mouse Embryonic Stem Cells
Core pluripotency factors, such as Oct4, Sox2, and Nanog, play important roles in maintaining embryonic stem cell (ESC) identity by autoregulatory feedforward loops. Nevertheless, the mechanism that provides precise control of the levels of the ESC core factors without indefinite amplification has remained elusive. Here, we report the direct repression of core pluripotency factors by Tgif1, a previously known terminal repressor of TGF beta/activin/nodal signaling. Overexpression of Tgif1 reduces the levels of ESC core factors, whereas its depletion leads to the induction of the pluripotency factors. We confirm the existence of physical associations between Tgif1 and Oct4, Nanog, and HDAC1/2 and further show the level of Tgif1 is not significantly altered by treatment with an activator/inhibitor of the TGF beta/activin/nodal signaling. Collectively, our findings establish Tgif1 as an integral member of the core regulatory circuitry of mouse ESCs that counterbalances the levels of the core pluripotency factors in a TGF beta/activin/nodal-independent manner.Cancer Prevention Research Institute of Texas (CPRIT) R1106Molecular Bioscience
Stoichiometry and Grain Boundaries Control by Spark Plasma Sintering in Ba0.6Sr0.4TiO3:Mn/MgO Composites
LaNbO4/La3NbO7 and LaNbO4/LaNb3O9 cer-cer composites were prepared by impregnating Ca-doped LaNbO4 powder, synthesized by spray pyrolysis, with La- or Nb-precursor solutions. The sintering of the calcined powders was investigated by dilatometry, and dense composites were prepared by conventional sintering, hot pressing, and spark plasma sintering. The particle size of the starting powders was about 50 nm, and the average grain size of the dense materials ranged from 100 nm and upwards, depending on the sintering temperature, sintering procedure, and the phase composition. The unit cell parameters of LaNbO4 showed a finite size effect and approached the cell parameters of tetragonal LaNbO4 with decreasing crystallite size, both for the single-phase material and the composites. The minority phase (La3NbO7 or LaNb3O9) were observed as isolated grains and accumulated at triple points and not along the grain boundaries, pointing to a large dihedral angle between the phases. The calcium-solubility in the minority phases was larger than in LaNbO4, which corresponds well with previous reports. The electrical conductivity of the heterodoped materials was similar to, or lower than, that for Ca-doped LaNbO4
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