Massive Burn Injuries: Characteristics and Outcomes From a Single Institution

Massive burn injuries are a unique patient population with unique treatment paradigms. Data from 155 adult patients, admitted from 2009 to 2019, with >50% total body surface area burns (TBSA) were collected and analyzed. Average burn size was 70% TBSA and 63% had a concomitant inhalation injury. Approximately 30% of patients (46/155) transitioned to comfort care-only measures within 24 hours of admission. Standard treatment patients were younger (37 ± 13 vs 60 ± 19 years; p < .00001), male (94% vs 28%; p = .001) and had smaller TBSA (66 ± 13 vs 80 ± 16; p < .00001). Of the standard treatment group, 72 (66%) survived to discharge. Survivors had smaller TBSA (64 ± 13 vs 71 ± 13; p = .003), less third-degree TBSA (48 ± 25 vs 71 ± 13; p = .003) and lower incidence of renal failure requiring dialysis (22% vs 73%, p < .00001). Multivariate regression analysis showed that age (OR 1.05; p = .025), total TBSA (OR 1.07; p = .005), and renal failure (OR 10.2; p = .00005) were independently associated with mortality. Inhalation injury was not significantly associated with mortality. About 23% (35/155) of patients had a psychiatric condition on admission and 19% (30/155) of patients were burned attempting suicide. Patients with psychiatric conditions spent more time in the hospital (62 vs 30 days; p = .004), more time on ventilator (31 vs 12 days; p = .046), underwent more surgery (4 vs 2 operations, p = .03), and were less likely to die (34% vs 59%; p = .02). In summary, age, burn size, and renal failure were independently associated with mortality, with renal failure being the strongest factor. Psychiatric conditions are prevalent pre-injury and tend to require more inpatient care.

Role of Food Handlers in Norovirus Outbreaks in London and South East England, 2013 to 2015

Outbreaks caused by norovirus infection are common and occur throughout the year. Outbreaks can be related to food outlets either through a contaminated food source or an infected food handler. Both asymptomatic and symptomatic food handlers are potentially implicated in outbreaks, but evidence of transmission is limited. To understand potential food handler transmission in outbreak scenarios, epidemiological and microbiological data on possible and confirmed norovirus outbreaks reported in London and South East England in a 2-year period were reviewed. One hundred eighty-six outbreaks were associated with a food outlet or registered caterer in this period. These occurred throughout the year with peaks in quarter 1 of study years. A case series of 17 outbreaks investigated by the local field epidemiological service were evaluated further, representing more than 606 cases. In five outbreaks, symptomatic food handlers were tested and found positive for norovirus. In four outbreaks, symptomatic food handlers were not tested. Asymptomatic food handlers were tested in three outbreaks but positive for norovirus in one only. Environmental sampling did not identify the causative agent conclusively in any of the outbreaks included in this analysis. Food sampling identified norovirus in one outbreak. Recommendations from this study include for outbreak investigations to encourage testing of symptomatic food handlers and for food and environmental samples to be taken as soon as possible. In addition, sampling of asymptomatic food handlers should be considered when possible. However, in light of the complexity in conclusively identifying a source of infection, general measures to improve hand hygiene are recommended, with specific education among food handlers about the potential for foodborne pathogen transmission during asymptomatic infection, as well as reinforcing the importance of self-exclusion from food handling activities when symptomatic.

Arabidopsis transcription factors: genome-wide comparative analysis among eukaryotes

The completion of the Arabidopsis thaliana genome sequence allows a comparative analysis of transcriptional regulators across the three eukaryotic kingdoms. Arabidopsis dedicates over 5% of its genome to code for more than 1500 transcription factors, about 45% of which are from families specific to plants. Arabidopsis transcription factors that belong to families common to all eukaryotes do not share significant similarity with those of the other kingdoms beyond the conserved DNA binding domains, many of which have been arranged in combinations specific to each lineage. The genome-wide comparison reveals the evolutionary generation of diversity in the regulation of transcription.

Evolutionary diversity of symbiotically induced nodule MADS box genes: characterization of nmhC5, a member of a novel subfamily

Unique organs called nodules form on legume roots in response to intracellular infection by soil bacteria in the genus Rhizobium. This study describes a new MADS box gene, nmhC5, which along with nmh7 (J. Heard and K. Dunn, Proc. Natl. Acad. Sci. USA 92:5273-5277, 1995), is expressed in alfalfa (Medicago sativa) root nodules. Together, these genes represent the first putative transcription factors identified in nodules. Expression in a root-derived structure supports the growing sentiment that MADS box proteins have diverse roles in plant development. Comparison of the putative translation product of nmhC5 with those of other reported members of the MADS box family suggests that the overall structure of nmhC5 is conserved. Evolutionary analysis among the MADS box family showed that nmhC5 is orthologous to a root-expressed clone in Arabidopsis thaliana, agl17, and that nmh7 is similar to the floral subfamily with AP3 (DefA)/PI (Glo). Consistent with a prediction of homodimer formation, NMHC5 was shown to bind a CArG consensus sequence in vitro. In contrast, NMH7, which shows structural similarity to MADS box proteins that form heterodimers, did not bind the CArG element in an in vitro DNA-binding assay, suggesting the existence of an unknown dimer partner. The root-derived MADS box genes constitute a novel subfamily of vegetatively expressed MADS box genes. The evolutionary diversity between nmh7 and nmhC5 could represent an overall mechanistic conservation between plant developmental processes or could mean that nmh7 and nmhC5 make fundamentally different contributions to the development of the nodule.

Symbiotic induction of a MADS-box gene during development of alfalfa root nodules

In response to infection by Rhizobium, highly differentiated organs called nodules form on legume roots. Within these organs, the symbiotic association between the host plant and bacteria is established. A putative plant transcription factor, NMH7, has been identified in alfalfa root nodules. nmh7 contains a MADS-box DNA-binding region and shows homology to flower homeotic genes. This gene is a member of a multigene family in alfalfa and was identified on the basis of nucleic acid homology to plant regulatory protein genes (MADS-box-containing genes) from Antirrhinum and Arabidopsis. RNA analysis and in situ hybridization showed that expression of this class of regulatory genes is limited to the infected cells of alfalfa root nodules and is likely to be involved in the signal transduction pathway initiated by the bacterial symbiont, Rhizobium meliloti. The expression of nmh7 in a root-derived organ is unusual for this class of regulatory genes.

Characterization of a nodule-enhanced glutamine synthetase from alfalfa: nucleotide sequence, in situ localization, and transcript analysis

We have characterized two glutamine synthetase (GS) cDNA clones (pGS13 and pGS100) representing mRNA from root nodules of alfalfa. pGS13 is a full-length version of a previously isolated partial cDNA from an alfalfa nodule cDNA library, while pGS100 was previously isolated from an alfalfa suspension culture cDNA library. Using the 3' untranslated region of the two cDNAs as gene-specific probes, we have shown that the GS genes represented by pGS100 and pGS13 are expressed in all organs tested, although at varying levels. pGS13, however, represents the nodule-enhanced GS gene class. Genomic Southern blot analysis using gene-specific probes shows multiple hybridizing bands, in each case suggesting multiple genes and/or alleles for each class of cytoplasmic GS genes. In situ hybridization of alfalfa nodule sections with gene-specific antisense RNA probes has shown that the nodule-enhanced GS genes are induced in the invasion zone and that their expression is limited to the symbiotic zone, while the GS genes represented by pGS100 are induced in the early symbiotic zone and are expressed throughout the symbiotic and senescent zones. Transcripts for both sets of GS genes are localized in the infected cells and based on the spatial expression pattern it would appear that the two gene classes are induced independently of the onset of nitrogen fixation.

Castor bean toxicity re-examined: a new perspective

Commonly used references present a very gloomy prognosis for castor seed ingestion. This appears to be based chiefly on extrapolations from laboratory animal studies of toxicity of the component, ricin. This is not in concordance with actual experience when actual case report experience is sought out and examined in detail. The literature has been confused by recursive references among secondary sources and mortality statistics have been distorted by reliance on data generated nearly a century ago which do not accurately reflect the capabilities of modern medical management. This is elucidated by actually tracking down and studying difficult-to-find original case reports from the early decades of the 20th century. It is time to reappraise our estimates of the hazard of ingesting castor seeds in the light of present day medical capabilities.