Subject(s)
Emphysema , Klebsiella Infections , Klebsiella pneumoniae , Pyelonephritis , Humans , Anti-Bacterial Agents/therapeutic use , Australia/epidemiology , Emphysema/microbiology , Klebsiella Infections/diagnosis , Klebsiella Infections/microbiology , Klebsiella pneumoniae/isolation & purification , Pyelonephritis/microbiologyABSTRACT
Cuticular waxes of plants impart tolerance to many forms of environmental stress and help shed dangerous human pathogens on edible plant parts. Although the chemical composition of waxes on a wide variety of important crops has been described, a detailed wax compositional analysis has yet to be reported for lettuce (Lactuca sativa L.), one of the most widely consumed vegetables. We present herein the leaf wax content and composition of 12 genetically diverse lettuce cultivars sampled across five time points during their vegetative growth phase in the field. Mean total leaf wax amounts across all cultivars varied little over 28 days of vegetative growth, except for a notable decrease in total waxes following a major precipitation event, presumably due to wax degradation from wind and rain. All lettuce cultivars were found to contain a unique wax composition highly enriched in 22- and 24-carbon length 1-alcohols (docosanol and tetracosanol, respectively). In our report, the dominance of these shorter chain length 1-alcohols as wax constituents represents a relatively rare phenotype in plants. The ecological significance of these dominant and relatively short 1-alcohols is still unknown. Although waxes have been a target for improvement of various crops, no such work has been reported for lettuce. This study lays the groundwork for future research that aims to integrate cuticular wax characteristics of field grown plants into the larger context of lettuce breeding and cultivar development.
ABSTRACT
BACKGROUND: Western Australia (WA) was in a unique position to experience coronavirus disease 2019 (COVID-19) in a highly vaccinated and geographically isolated population. AIM: To describe the COVID-19 Omicron experience at the only quaternary hospital in WA following border opening from 3 March to 11 May 2022. PARTICIPANTS: A total of 158 adults with microbiologically confirmed COVID-19 were admitted to the respiratory or intensive care unit (ICU). OUTCOMES: Admission numbers, disease severity, prevalence of COVID-19 deterioration risk factors, immunisation status, severity of infection, immunosuppression and treatment regimen. RESULTS: One hundred fifty-eight COVID-19-positive patients were admitted to the respiratory ward (n = 123) and the ICU (n = 35) during the study period. COVID-19 infection was the primary admission reason in 32.9% of patients, 51.3% were male and the median age was 62 years. Aboriginal or Torres Strait Islanders (ATSI) were overrepresented (13.3%). Care was predominantly ward based (77.2%). Nearly half of the patients had mild COVID-19 (49.4%). Dexamethasone was the most common treatment provided to patients (58.2%). The median length of stay was 5.8 days (interquartile range, 5-15). Eight patients died during the study period (5.1%), with three of those deaths attributable to COVID-19. CONCLUSIONS: COVID-19 case numbers following WA state border opening were of lower care acuity and disease severity than predicted. Two-thirds of admissions were for other primary diagnoses, with incidental COVID detection. Hospital admissions were overrepresented by partially or unvaccinated patients and by ATSI Australians. An increase in social support along with general and geriatric medicine speciality input were required to treat hospitalised COVID-19 cases in the WA Omicron wave.
Subject(s)
COVID-19 , Adult , Humans , Male , Aged , Middle Aged , Female , COVID-19/epidemiology , Western Australia/epidemiology , Australia/epidemiology , Intensive Care Units , HospitalizationABSTRACT
OBJECTIVES: To examine the utility and efficacy of a multifaceted protocol for the administration of intravesical bacillus Calmette-Guerin (BCG) for non-muscle-invasive bladder cancer (NMIBC). SUBJECTS AND METHODS: A multicenter retrospective review was conducted among 83 patients undergoing Fremantle protocol intravesical BCG for NMIBC within 4 major hospitals in Western Australia between January 2016 and December 2018. The Fremantle protocol consists of weekly BCG instillations for 6 weeks during the induction phase, followed by monthly BCG instillations for 10 months during the maintenance phase with integrated clearance-to-proceed algorithms for urine MSU checks, flexible cystoscopies performed at 3 monthly intervals during maintenance BCG, and repeat GA cystoscopies with four quadrant bladder biopsies routinely obtained following the completion of induction and maintenance treatment. RESULTS: For patients undergoing Fremantle protocol BCG, 98.8% (82/83) and 75.9% (63/83) of patients completed their induction and maintenance courses of BCG, respectively. Induction BCG was delivered over a median duration of 35 days (range 34-84 days), and maintenance BCG was delivered over a median duration of 266 days (range 1-682 days). The tumor recurrence rate was 10.8% (9/83) at the time of post-induction biopsies, 2.4% (2/83) during maintenance treatment, 0% (0/60) at the time of post-maintenance biopsies, and 8.8% (5/57) after a median further follow-up of 16 months (range 0-51 months). CONCLUSION: The Fremantle protocol appears to be a safe and effective BCG regimen with several advantages over other BCG protocols, including high completion rates, low recurrence rates, and being highly pragmatic.
Subject(s)
Non-Muscle Invasive Bladder Neoplasms , Urinary Bladder Neoplasms , Humans , BCG Vaccine/therapeutic use , Treatment Outcome , Administration, Intravesical , Neoplasm Recurrence, Local/drug therapy , Neoplasm Recurrence, Local/pathology , Urinary Bladder Neoplasms/drug therapy , Urinary Bladder Neoplasms/pathology , Neoplasm Invasiveness/pathology , Multicenter Studies as TopicABSTRACT
Epidemiologic data on invasive group C/G Streptococcus (iGCGS) infections are sparse internationally. Linked population-level hospital, pathology, and death data were used to describe the disease burden in Western Australia, Australia, during 2000-2018 compared with that of invasive group A Streptococcus (GAS, Streptococcus pyogenes) infections. Of 1,270 cases, 866 (68%) occurred in men. Patients with iGCGS infection were older (median age 62 years) than those with invasive GAS (median age 44 years; p<0.0001). The age and sex-adjusted incidence rate ratio by year was 1.08 (95% CI 1.07-1.09). The incidence rate ratio for Indigenous compared with non-Indigenous Australians was 3.6 (95% CI 3.0-4.3). The all-cause 90-day death rate was 9% for iGCGS infection compared with 7% for invasive GAS (p = 0.03). iGCGS infection was more common in men and older persons and had a higher death rate, perhaps reflecting the effect of age and comorbidities on incidence and death.
Subject(s)
Streptococcal Infections , Streptococcus pyogenes , Male , Humans , Aged , Aged, 80 and over , Middle Aged , Adult , Western Australia/epidemiology , Australia/epidemiology , Streptococcal Infections/epidemiology , IncidenceABSTRACT
Recent advances have enabled the creation of wireless, "dry" electroencephalography (EEG) recording systems, and easy-to-use engaging tasks, that can be operated repeatedly by naïve users, unsupervised in the home. Here, we evaluated the validity of dry-EEG, cognitive task gamification, and unsupervised home-based recordings used in combination. Two separate cohorts of participants-older and younger adults-collected data at home over several weeks using a wireless dry EEG system interfaced with a tablet for task presentation. Older adults (n = 50; 25 females; mean age = 67.8 years) collected data over a 6-week period. Younger male adults (n = 30; mean age = 25.6 years) collected data over a 4-week period. All participants were asked to complete gamified versions of a visual Oddball task and Flanker task 5-7 days per week. Usability of the EEG system was evaluated via participant adherence, percentage of sessions successfully completed, and quantitative feedback using the System Usability Scale. In total, 1,449 EEG sessions from older adults (mean = 28.9; SD = 6.64) and 684 sessions from younger adults (mean = 22.87; SD = 1.92) were collected. Older adults successfully completed 93% of sessions requested and reported a mean usability score of 84.5. Younger adults successfully completed 96% of sessions and reported a mean usability score of 88.3. Characteristic event-related potential (ERP) components-the P300 and error-related negativity-were observed in the Oddball and Flanker tasks, respectively. Using a conservative threshold for inclusion of artifact-free data, 50% of trials were rejected per at-home session. Aggregation of ERPs across sessions (2-4, depending on task) resulted in grand average signal quality with similar Standard Measurement Error values to those of single-session wet EEG data collected by experts in a laboratory setting from a young adult sample. Our results indicate that easy-to-use task-driven EEG can enable large-scale investigations in cognitive neuroscience. In future, this approach may be useful in clinical applications such as screening and tracking of treatment response.
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BACKGROUND: Antifungal administration via outpatient parenteral antimicrobial therapy (OPAT) is infrequent. As patients with invasive fungal infections (IFIs) receiving OPAT are at high risk of readmissions, careful, risk-based patient selection and monitoring is important. OBJECTIVES: To describe our experience managing IFIs via OPAT, including assessment of risk factors associated with unplanned readmissions. PATIENTS AND METHODS: A retrospective cohort study of outpatients from two tertiary hospitals in Western Australia managed with parenteral antifungals for the treatment of IFIs from 2012 to 2020. Outcomes assessed were unplanned OPAT-related readmissions; adverse events and achievement of treatment aim at the completion of OPAT. RESULTS: Forty-six patients were included, encompassing 696 OPAT days. Twenty-three (50%) patients received intravenous (IV) liposomal amphotericin B (L-AmB), 23 (50%) received IV echinocandins and one (2%) patient received IV fluconazole. One patient received both IV L-AmB and an echinocandin. Unplanned OPAT-related readmissions occurred in 13 (28%) patients and any adverse event occurred in 19 (41%), most commonly nephrotoxicity amongst patients receiving L-AmB. On univariate analysis, unplanned OPAT-related readmissions were more common in Mucorales infection, L-AmB doses of ≥5 mg/kg and otorhinolaryngologic (ENT) infections. At the completion of OPAT, attainment of treatment aims occurred in 28 (61%) patients. CONCLUSIONS: Patients receiving parenteral antifungals via OPAT experience high rates of unplanned readmissions and adverse events. Risk factor identification may facilitate optimal patient selection and establishment of treatment aims.
Subject(s)
Anti-Infective Agents , Outpatients , Ambulatory Care , Amphotericin B , Anti-Bacterial Agents , Antifungal Agents/adverse effects , Echinocandins , Fluconazole , Humans , Retrospective StudiesABSTRACT
Intravesical Bacillus Calmette-Guérin (BCG) immunotherapy for non-muscle invasive bladder cancer (NMIBC) has been used as a treatment since 1976. It is effective in reducing disease recurrence and progression, with mostly self-limiting or mild side effects. Serious complications are rare and thought to be either related to systemic BCG infection (BCG-osis) or a systemic inflammatory response, and often require systemic anti-tuberculous therapy. We report a rare case of urethral fistulation leading to perineal BCG-abscess during intravesical BCG immunotherapy for high grade bladder cancer. This ultimately required systemic anti-tuberculous therapy and cessation of intravesical BCG treatment.
ABSTRACT
BACKGROUND: Although common, antimicrobial allergy labels (AAL) rarely reflect immunologically-mediated hypersensitivity and can lead to poorer outcomes from alternative antimicrobial agents. Antimicrobial stewardship programs are ideally placed to assess AAL early as a means of improving antimicrobial use. AIMS: To quantify the prevalence of AAL in patients referred for antimicrobial stewardship review and assess their impact on antibiotic prescribing, patient mortality, hospital length of stay, readmission and rates of multidrug-resistant infections. METHODS: We conducted a retrospective analysis of adult patients referred for inpatient antimicrobial prospective audit and feedback rounds (PAFR) through an electronic referral system (eReferrals) over a 12-month period in 2015. Outcome data were collected for a period of 36 months following the initial review. RESULTS: Of the 639 patient records reviewed, 630 met inclusion criteria; 103 (16%) had an AAL, of which 82 (13%) had reported allergies to ß-lactam antibiotics. Those with AAL were significantly less likely to be receiving guideline-recommended antimicrobial therapy (50% vs 64%, P = 0.0311); however, there were no significant difference in mortality, hospital length of stay, readmission or increased incidence of multidrug-resistant infections. CONCLUSIONS: Our cohort demonstrated that AAL was associated with reduced adherence to antibiotic guidelines. The lack of association with adverse outcomes may reflect limitations within the study including retrospective cohort study numbers and observational nature, further skewed by high rates of poor documentation. A clear opportunity exists for antimicrobial stewardship programs to incorporate allergy assessment, de-labelling, challenge and referral into these rounds.
Subject(s)
Anti-Infective Agents , Antimicrobial Stewardship , Drug Hypersensitivity , Adult , Anti-Bacterial Agents/adverse effects , Drug Hypersensitivity/diagnosis , Drug Hypersensitivity/epidemiology , Humans , Retrospective StudiesABSTRACT
BACKGROUND: Outpatient parenteral antimicrobial therapy (OPAT) delivery using peripherally inserted central catheters is associated with a risk of catheter related thrombosis (CRT). Individualised preventative interventions may reduce this occurrence, however patient selection is hampered by a lack of understanding of risk factors. We aimed to identify patient, infection or treatment related risk factors for CRT in the OPAT setting. METHODS: Retrospective case control study (1:3 matching) within OPAT services at two tertiary hospitals within Australia. RESULTS: Over a 2 year period, encompassing OPAT delivery to 1803 patients, there were 19 cases of CRT, giving a prevalence of 1.1% and incidence of 0.58/1000 catheter days. Amongst the cases of CRT, there were nine (47%) unplanned readmissions and two (11%) pulmonary emboli. Compared to controls, cases had a higher frequency of malposition of the catheter tip (4/19 (21%) vs 0/57 (0%), p = 0.003) and complicated catheter insertion (3/19 (16%) vs 1/57 (2%), p = 0.046). CONCLUSIONS: Although CRTs during OPAT are infrequent, they often have clinically significant sequelae. Identification of modifiable vascular access related predictors of CRT should assist with patient risk stratification and guide risk reduction strategies.
Subject(s)
Anti-Infective Agents , Catheterization, Peripheral , Thrombosis , Anti-Bacterial Agents , Anti-Infective Agents/adverse effects , Case-Control Studies , Catheterization, Peripheral/adverse effects , Catheters/adverse effects , Humans , Infusions, Parenteral/adverse effects , Outpatients , Retrospective Studies , Risk Factors , Thrombosis/diagnosis , Thrombosis/etiology , Thrombosis/prevention & controlABSTRACT
BACKGROUND: Amoxicillin plus ceftriaxone combination therapy is now standard of care for enterococcal endocarditis. Due to amoxicillin instability in infusion devices, benzylpenicillin plus ceftriaxone may be substituted to facilitate outpatient parenteral antimicrobial therapy (OPAT) delivery, despite lack of guideline endorsement. OBJECTIVES: To assess the clinical efficacy of benzylpenicillin plus ceftriaxone for the management of enterococcal endovascular infections, in addition to assessing this combination's in vitro synergy. PATIENTS AND METHODS: Retrospective cohort study assessing unplanned readmissions, relapses and mortality for 20 patients with endovascular Enterococcus faecalis infections treated with benzylpenicillin plus ceftriaxone delivered via OPAT. For a subset of isolates, synergism for both amoxicillin and benzylpenicillin in combination with ceftriaxone was calculated using a chequerboard method. RESULTS: Patients had endovascular infections of native cardiac valves (nâ=â11), mechanical or bioprosthetic cardiac valves (nâ=â7), pacemaker leads (nâ=â1) or left ventricular assistant devices (nâ=â1). The median duration of OPAT was 22 days, and the most frequent antimicrobial regimen was benzylpenicillin 14 g/day via continuous infusion and ceftriaxone 4 g once daily via short infusion. Rates of unplanned readmissions were high (30%), although rates of relapsed bacteraemia (5%) and 1 year mortality (15%) were comparable to the published literature. Benzylpenicillin less frequently displayed a synergistic interaction with ceftriaxone when compared with amoxicillin (3 versus 4 out of 6 isolates). CONCLUSIONS: Lower rates of synergistic antimicrobial interaction and a significant proportion of unplanned readmissions suggest clinicians should exercise caution when treating enterococcal endovascular infection utilizing a combination of benzylpenicillin and ceftriaxone via OPAT.
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Access to affordable, objective and scalable biomarkers of brain function is needed to transform the healthcare burden of neuropsychiatric and neurodegenerative disease. Electroencephalography (EEG) recordings, both resting and in combination with targeted cognitive tasks, have demonstrated utility in tracking disease state and therapy response in a range of conditions from schizophrenia to Alzheimer's disease. But conventional methods of recording this data involve burdensome clinic visits, and behavioural tasks that are not effective in frequent repeated use. This paper aims to evaluate the technical and human-factors feasibility of gathering large-scale EEG using novel technology in the home environment with healthy adult users. In a large field study, 89 healthy adults aged 40-79 years volunteered to use the system at home for 12 weeks, 5 times/week, for 30 min/session. A 16-channel, dry-sensor, portable wireless headset recorded EEG while users played gamified cognitive and passive tasks through a tablet application, including tests of decision making, executive function and memory. Data was uploaded to cloud servers and remotely monitored via web-based dashboards. Seventy-eight participants completed the study, and high levels of adherence were maintained throughout across all age groups, with mean compliance over the 12-week period of 82% (4.1 sessions per week). Reported ease of use was also high with mean System Usability Scale scores of 78.7. Behavioural response measures (reaction time and accuracy) and EEG components elicited by gamified stimuli (P300, ERN, Pe and changes in power spectral density) were extracted from the data collected in home, across a wide range of ages, including older adult participants. Findings replicated well-known patterns of age-related change and demonstrated the feasibility of using low-burden, large-scale, longitudinal EEG measurement in community-based cohorts. This technology enables clinically relevant data to be recorded outside the lab/clinic, from which metrics underlying cognitive ageing could be extracted, opening the door to potential new ways of developing digital cognitive biomarkers for disorders affecting the brain.
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Cytoplasmic lipid droplets (LDs) are evolutionarily conserved organelles that store neutral lipids and play critical roles in plant growth, development, and stress responses. However, the molecular mechanisms underlying their biogenesis at the endoplasmic reticulum (ER) remain obscure. Here we show that a recently identified protein termed LD-associated protein [LDAP]-interacting protein (LDIP) works together with both endoplasmic reticulum-localized SEIPIN and the LD-coat protein LDAP to facilitate LD formation in Arabidopsis thaliana. Heterologous expression in insect cells demonstrated that LDAP is required for the targeting of LDIP to the LD surface, and both proteins are required for the production of normal numbers and sizes of LDs in plant cells. LDIP also interacts with SEIPIN via a conserved hydrophobic helix in SEIPIN and LDIP functions together with SEIPIN to modulate LD numbers and sizes in plants. Further, the co-expression of both proteins is required to restore normal LD production in SEIPIN-deficient yeast cells. These data, combined with the analogous function of LDIP to a mammalian protein called LD Assembly Factor 1, are discussed in the context of a new model for LD biogenesis in plant cells with evolutionary connections to LD biogenesis in other eukaryotes.
Subject(s)
Arabidopsis Proteins/physiology , Arabidopsis/genetics , Lipid Droplets/physiology , Organelle Biogenesis , Arabidopsis/metabolism , Arabidopsis Proteins/geneticsABSTRACT
OBJECTIVE: To quantify the burden of invasive group A Streptococcus (GAS) disease in Western Australia during 2000-2018. DESIGN, SETTING: Population-based data linkage study: Hospital Morbidity Data Collection (HMDC; all WA public and private hospital records), PathWest pathology data (government-owned pathology services provider), and death registrations. PARTICIPANTS: People with invasive GAS disease, defined by an isolate from a normally sterile site (PathWest) or a hospital-based principal ICD-10-AM diagnosis code (HMDC). MAIN OUTCOME MEASURES: Incidence of invasive GAS disease; median length of hospital stay; all-cause mortality. RESULTS: We identified 2237 cases of GAS disease during 2000-2018; 1283 were in male patients (57%). 1950 cases had been confirmed by GAS isolates from normally sterile tissues (87%; including 1089 from blood [56% of cases] and 750 from tissue [38%]). The age-standardised incidence increased from 2.0 (95% CI, 1.4-2.7) cases per 100 000 population in 2000 to 9.1 (95% CI, 7.9-10.2) cases per 100 000 in 2017 (by year, adjusted for age group and sex: incidence rate ratio [IRR], 1.09; 95% CI, 1.08-1.10). Incidence was consistently higher among Indigenous than non-Indigenous Australians (year-adjusted IRR, 13.1; 95% CI, 11.3-15.1). All-cause 30-day mortality was 5% (116 deaths), and 90-day mortality 7% (156 deaths); 30-day mortality, adjusted for age group and sex, was not statistically significantly different for cases involving Indigenous or non-Indigenous patients (adjusted odds ratio, 0.8; 95% CI, 0.6-1.1). CONCLUSIONS: The incidence of invasive GAS disease in WA increased between 2000 and 2018, particularly among Indigenous Australians. Mandatory notification of invasive GAS disease would therefore be appropriate. The social determinants of differences in incidence should be addressed, and other relevant host, pathogen, and health system factors investigated.
Subject(s)
Native Hawaiian or Other Pacific Islander/statistics & numerical data , Streptococcal Infections/epidemiology , Streptococcus pyogenes , Adolescent , Adult , Age Factors , Aged , Child , Child, Preschool , Female , Humans , Incidence , Infant , Male , Middle Aged , Sex Factors , Streptococcal Infections/microbiology , Streptococcal Infections/mortality , Western Australia/epidemiology , Young AdultABSTRACT
Lipid droplets (LDs) are neutral-lipid-containing organelles found in all kingdoms of life and are coated with proteins that carry out a vast array of functions. Compared to mammals and yeast, relatively few LD proteins have been identified in plants, particularly those associated with LDs in vegetative (non-seed) cell types. Thus, to better understand the cellular roles of LDs in plants, a more comprehensive inventory and characterization of LD proteins is required. Here, we performed a proteomics analysis of LDs isolated from drought-stressed Arabidopsis leaves and identified EARLY RESPONSIVE TO DEHYDRATION 7 (ERD7) as a putative LD protein. mCherry-tagged ERD7 localized to both LDs and the cytosol when ectopically expressed in plant cells, and the protein's C-terminal senescence domain (SD) was both necessary and sufficient for LD targeting. Phylogenetic analysis revealed that ERD7 belongs to a six-member family in Arabidopsis that, along with homologs in other plant species, is separated into two distinct subfamilies. Notably, the SDs of proteins from each subfamily conferred targeting to either LDs or mitochondria. Further, the SD from the ERD7 homolog in humans, spartin, localized to LDs in plant cells, similar to its localization in mammals; although, in mammalian cells, spartin also conditionally localizes to other subcellular compartments, including mitochondria. Disruption of ERD7 gene expression in Arabidopsis revealed no obvious changes in LD numbers or morphology under normal growth conditions, although this does not preclude a role for ERD7 in stress-induced LD dynamics. Consistent with this possibility, a yeast two-hybrid screen using ERD7 as bait identified numerous proteins involved in stress responses, including some that have been identified in other LD proteomes. Collectively, these observations provide new insight to ERD7 and the SD-containing family of proteins in plants and suggest that ERD7 may be involved in functional aspects of plant stress response that also include localization to the LD surface.
ABSTRACT
Production of hydroxy fatty acids (HFAs) in transgenic crops represents a promising strategy to meet our demands for specialized plant oils with industrial applications. The expression of Ricinus communis (castor) OLEATE 12-HYDROXYLASE (RcFAH12) in Arabidopsis has resulted in only limited accumulation of HFAs in seeds, which probably results from inefficient transfer of HFAs from their site of synthesis (phosphatidylcholine; PC) to triacylglycerol (TAG), especially at the sn-1/3 positions of TAG. Phospholipase As (PLAs) may be directly involved in the liberation of HFAs from PC, but the functions of their over-expression in HFA accumulation and distribution at TAG in transgenic plants have not been well studied. In this work, the functions of lecithin:cholesterol acyltransferase-like PLAs (LCAT-PLAs) in HFA biosynthesis were characterized. The LCAT-PLAs were shown to exhibit homology to LCAT and mammalian lysosomal PLA2 , and to contain a conserved and functional Ser/His/Asp catalytic triad. In vitro assays revealed that LCAT-PLAs from the HFA-accumulating plant species Physaria fendleri (PfLCAT-PLA) and castor (RcLCAT-PLA) could cleave acyl chains at both the sn-1 and sn-2 positions of PC, and displayed substrate selectivity towards sn-2-ricinoleoyl-PC over sn-2-oleoyl-PC. Furthermore, co-expression of RcFAH12 with PfLCAT-PLA or RcLCAT-PLA, but not Arabidopsis AtLCAT-PLA, resulted in increased occupation of HFA at the sn-1/3 positions of TAG as well as small but insignificant increases in HFA levels in Arabidopsis seeds compared with RcFAH12 expression alone. Therefore, PfLCAT-PLA and RcLCAT-PLA may contribute to HFA turnover on PC, and represent potential candidates for engineering the production of unusual fatty acids in crops.
Subject(s)
Brassicaceae/enzymology , Phosphatidylcholine-Sterol O-Acyltransferase/metabolism , Phosphatidylcholines/metabolism , Plant Proteins/metabolism , Ricinus/enzymology , Arabidopsis/metabolism , Brassicaceae/genetics , Fatty Acids/metabolism , Lysophospholipids , Phosphatidylcholine-Sterol O-Acyltransferase/genetics , Plant Proteins/genetics , Plant Roots/metabolism , Plants, Genetically Modified , Protein Structure, Tertiary , Ricinus/genetics , Seeds/metabolism , Substrate SpecificityABSTRACT
SEIPIN proteins are localized to endoplasmic reticulum (ER)-lipid droplet (LD) junctions where they mediate the directional formation of LDs into the cytoplasm in eukaryotic cells. Unlike in animal and yeast cells, which have single SEIPIN genes, plants have three distinct SEIPIN isoforms encoded by separate genes. The mechanism of SEIPIN action remains poorly understood, and here we demonstrate that part of the function of two SEIPIN isoforms in Arabidopsis (Arabidopsis thaliana), AtSEIPIN2 and AtSEIPIN3, may depend on their interaction with the vesicle-associated membrane protein (VAMP)-associated protein (VAP) family member AtVAP27-1. VAPs have well-established roles in the formation of membrane contact sites and lipid transfer between the ER and other organelles, and here, we used a combination of biochemical, cell biology, and genetics approaches to show that AtVAP27-1 interacts with the N termini of AtSEIPIN2 and AtSEIPIN3 and likely supports the normal formation of LDs. This insight indicates that the ER membrane tethering machinery in plant cells could play a role with select SEIPIN isoforms in LD biogenesis at the ER, and additional experimental evidence in Saccharomyces cerevisiae supports the possibility that this interaction may be important in other eukaryotic systems.
Subject(s)
Arabidopsis Proteins/metabolism , Arabidopsis/metabolism , Lipid Droplets/metabolism , R-SNARE Proteins/metabolism , Arabidopsis/cytology , Arabidopsis/genetics , Endoplasmic Reticulum/metabolism , Phylogeny , Plant Cells/metabolism , Plants, Genetically Modified , Protein Domains , Seeds/metabolism , Nicotiana/genetics , Two-Hybrid System TechniquesABSTRACT
A 65-year-old lady was admitted with urosepsis and imaging suggesting right sided hydronephrosis secondary to a filling defect consistent with a fungal bezoar. An indwelling urinary catheter and a right percutaneous nephrostomy tube were inserted. Candida glabrata cultured from urine was resistant to fluconazole. Amphotericin B was instilled into the renal pelvis via the nephrostomy tube while intravenous liposomal amphotericin was administered daily along with oral flucytosine. This multi-modal antifungal administration was continued for 14 days. Clinical and biochemical improvement was achieved and repeat imaging showed complete resolution of the filling defects and hydronephrosis.