A case report of iatrogenic gas gangrene post colonoscopy successfully treated with conservative management- is surgery always necessary?

Background: Colonoscopy is a routine procedure in diagnosis and treatment of colonic disease. While generally regarded as a safe procedure, potentially fatal complications can occur. Gas gangrene is one such complication, with very high mortality. There are few cases of gas gangrene occurring after colonoscopy, making it one of the rarer complications of this procedure. There have been no previously reported cases of a patient surviving such an infection and the optimal treatment strategy is contentious. This report describes a case of intramural gas gangrene of the colon, treated conservatively with antibiotic therapy in which the patient survived with full recovery. Case presentation: A 71-year-old, previously healthy male presented 6 h post apparently uncomplicated colonoscopic polypectomy with rigors, nausea, vomiting and right upper quadrant pain. At presentation he was febrile at 40.1 °C but hemodynamically stable. Abdominal computed tomography revealed substantial colonic thickening and several focal intramural gas bubbles (pneumatosis intestinalis) surrounding the polypectomy site. Within 24 h post procedure he became hypotensive and was admitted to ICU in frank septic shock requiring inotropes, and with demonstrable septic myocardial depression. Bloods showed multi-organ derangement with leukocytosis, lactic acidosis, haemolytic anaemia and hyperbilirubinemia. A diagnosis of presumed Clostridial gas gangrene was made, and treatment was initiated with benzylpenicillin, clindamycin, metronidazole and vancomycin. After 4 days in ICU he was stepped down, and discharged after a further 10 days with no surgical or endoscopic interventions. At three-month review he reported being back to full health. Conclusions: This case demonstrates that gas gangrene infection is a possible complication of colonoscopic polypectomy. This is a cause of rapid deterioration in post-colonoscopy patients and has been misdiagnosed as colonic perforation in previously reported cases of retroperitoneal gas gangrene. Such misdiagnosis delays antibiotic therapy, which likely plays a role in the high mortality of this condition. Early diagnosis and initiation of antibiotic therapy with benzylpenicillin and clindamycin as seen in this case is essential for patient survival. While surgery is typically performed, non-operative management of pneumatosis intestinalis, and potentially gas gangrene is becoming more common and was utilized effectively in this patient

Studies on thyroidal protein biosynthesis in relation to thyroid hormone biosynthesis

1. The object of the study was the isolation from thyreoglobulin of peptides containing iodothyronines or iodotyrosines, followed by investigation of these peptides as the actual or potential sites of thyroid hormone synthesis in thyreoglobulin.2. A cell free preparation capable of incorporating amino acids into protein was isolated from rat thyroid. Some of the unusual properties of this preparation were studied.3. Thyroglobulin containing ¹⁴C-amino acids was isolated from whole rat thyroids after Incubation with ¹⁴C-amino acids. Under similar conditions sheep thyroid slices rapidly incorporated ¹⁴C- amino acids and ¹³¹I⁻ yielding thyroglobulia highly labelled with both isotopes.4. Thyroglobulin isolated from sheep thyroid slices was purified, by fractionation with ammonium sulphate or by gel filtration on Sephadex G-200. The purity of the preparation was determined by a variety of methods including gel filtration, electrophoresis and ultraoentrifugation. Suorose gradient centrifugation revealed a highly iodinated lighter protein fraction.5. Labelled thyroglobulin was hydrolysed by α-chymotrypsin and the resulting hydrolysate subjected to electrophoresis followed by chromatography at right angles (peptide mapping). Autoradiograms of these peptide maps revealed the presence of a number of peptides labelled with ¹³¹I₂ and a larger number labelled with ¹⁴C-tyrosine. None of the ¹³¹I-peptides was unequivocally labelled with ¹⁴C- tyrosine.6. The most highly labelled ¹³¹ I-peptides were isolated, in some cases purified by electrophoresis at pH 8.2, and their iodoamino acid contents found after pronase hydrolysis and chromatography. Each peptide contained only one iodotyrosine confirming the specific nature of tyrosyl iodination indicated by the small number of intensely labelled ¹³¹I-peptides compared with a larger number of ¹⁴C—tyrosine peptides.7. The approximate sizes of the ¹³¹I-peptides were determined by estimation ©i the bonds hydrolysed by αC-chymotrypsin and by gel filtration of the peptides on Sephadex 0-25.8. During the incorporation of ¹³¹I⁻ into thyroid slices over a period of 5 hr. the activity of each ¹³¹I-peptide, as a percentage of the total ¹³¹I₂ in thyroglobulin, did not alter although the ratio of the ¹³¹I-activities of mono- to diiodotyrosine fell throughout this period.9. Monoiodotyrosyl peptide A₅ was iodinated chemically with ¹³¹I₂. The product was not identical with already isolated diiodotyrosyl peptides of similar mobilities on peptide mapping.10. Peptide A₅ was associated with another peptide (separated by electrophoresis at pH 8.2) whose products of iodination were identical with those of A₅ and which, it is suggested, is the unlodinated form of A₅.11. This latter peptide taken together with A₅, is present as 4 moles per mole of thyroglobulin as determined by iodination with 131I₂ of known specifio aotivity. Two other peptides, N₉ and N₉ₐ' are each present as 5 moles per mole of thyroglobulin. It ya is suggested that this confirms the evidence that thyroglobulin oomprises four identioal sub-units and that iodotyrosyl residues can remain partially uniodinated as well as being mono- or diiodinated

An assay for argininosuccinate synthetase in Neurospora

An assay for argininosuccinate synthetase in Neurospor

RAS screening in colorectal cancer: a comprehensive analysis of the results from the UK NEQAS colorectal cancer external quality assurance schemes (2009–2016)

Evidence strongly indicates that extended RAS testing should be undertaken in mCRC patients, prior to prescribing anti-EGFR therapies. With more laboratories implementing testing, the requirement for External Quality Assurance schemes increases, thus ensuring high standards of molecular analysis. Data was analysed from 15 United Kingdom National External Quality Assessment Service (UK NEQAS) for Molecular Genetics Colorectal cancer external quality assurance (EQA) schemes, delivered between 2009 and 2016. Laboratories were provided annually with nine colorectal tumour samples for genotyping. Information on methodology and extent of testing coverage was requested, and scores given for genotyping, interpretation and clerical accuracy. There has been a sixfold increase in laboratory participation (18 in 2009 to 108 in 2016). For RAS genotyping, fewer laboratories now use Roche cobas®, pyrosequencing and Sanger sequencing, with more moving to next generation sequencing (NGS). NGS is the most commonly employed technology for BRAF and PIK3CA mutation screening. KRAS genotyping errors were seen in ≤10% laboratories, until the 2014–2015 scheme, when there was an increase to 16.7%, corresponding to a large increase in scheme participants. NRAS genotyping errors peaked at 25.6% in the first 2015–2016 scheme but subsequently dropped to below 5%. Interpretation and clerical accuracy scores have been consistently good throughout. Within this EQA scheme, we have observed that the quality of molecular analysis for colorectal cancer has continued to improve, despite changes in the required targets, the volume of testing and the technologies employed. It is reassuring to know that laboratories clearly recognise the importance of participating in EQA schemes

The Butcher-Oemler Effect in High Redshift X-ray Selected Clusters

We are engaged in a wide-field, multi-colour imaging survey of X-ray selected clusters at intermediate and high redshift. We present blue fractions for the first 8 out of 29 clusters, covering almost a factor of 100 in X-ray luminosity. We find no correlation of blue fraction with redshift or X-ray luminosity. The lack of a correlation with L$_{X}$, places strong constraints on the importance of ram-pressure stripping as a driver of the Butcher-Oemler effect.Comment: 4 pages, 4 figures, to be puplished in the proceedings of the ''Sesto 2001-Tracing Cosmic Evolution with Galaxy Clusters'', Sesto 3-6 July 2001, Italy, eds, Stefano Borgan

When two is better than one: Differences in characteristics of women using condoms only compared to those using condoms combined with an effective contraceptive

published_or_final_versio

Telling partners about chlamydia: how acceptable are the new technologies?

BACKGROUND Partner notification is accepted as a vital component in the control of chlamydia. However, in reality, many sexual partners of individuals diagnosed with chlamydia are never informed of their risk. The newer technologies of email and SMS have been used as a means of improving partner notification rates. This study explored the use and acceptability of different partner notification methods to help inform the development of strategies and resources to increase the number of partners notified. METHODS Semi-structured telephone interviews were conducted with 40 people who were recently diagnosed with chlamydia from three sexual health centres and two general practices across three Australian jurisdictions. RESULTS Most participants chose to contact their partners either in person (56%) or by phone (44%). Only 17% chose email or SMS. Participants viewed face-to-face as the "gold standard" in partner notification because it demonstrated caring, respect and courage. Telephone contact, while considered insensitive by some, was often valued because it was quick, convenient and less confronting. Email was often seen as less personal while SMS was generally considered the least acceptable method for telling partners. There was also concern that emails and SMS could be misunderstood, not taken seriously or shown to others. Despite these, email and SMS were seen to be appropriate and useful in some circumstances. Letters, both from the patients or from their doctor, were viewed more favourably but were seldom used. CONCLUSION These findings suggest that many people diagnosed with chlamydia are reluctant to use the new technologies for partner notification, except in specific circumstances, and our efforts in developing partner notification resources may best be focused on giving patients the skills and confidence for personal interaction.The study was funded by the Australian Federal Government Department of Health and Ageing Chlamydia Pilot Program of Targeted Grants

Dr1 (NC2) is present at tRNA genes and represses their transcription in human cells

Dr1 (also known as NC2{beta}) was identified as a repressor of RNA polymerase (pol) II transcription. It was subsequently shown to inhibit pol III transcription when expressed at high levels in vitro or in yeast cells. However, endogenous Dr1 was not detected at pol III-transcribed genes in growing yeast. In contrast, we demonstrate that endogenous Dr1 is present at pol III templates in human cells, as is its dimerization partner DRAP1 (also called NC2{alpha}). Expression of tRNA by pol III is selectively enhanced by RNAi-mediated depletion of endogenous human Dr1, but we found no evidence that DRAP1 influences pol III output in vivo. A stable association was detected between endogenous Dr1 and the pol III-specific transcription factor Brf1. This interaction may recruit Dr1 to pol III templates in vivo, as crosslinking to these sites increases following Brf1 induction. On the basis of these data, we conclude that the physiological functions of human Dr1 include regulation of pol III transcription

The Anti-Desmoglein 1 Autoantibodies in Pemphigus Vulgaris Sera are Pathogenic

Pemphigus vulgaris and pemphigus foliaceus are two closely related, but clinically and histologically distinct, autoimmune skin diseases. The autoantigens for pemphigus vulgaris and pemphigus foliaceus are desmoglein 3 and desmoglein 1, respectively. The anti-desmoglein 1 antibodies in pemphigus foliaceus and anti-desmoglein 3 antibodies in pemphigus vulgaris are pathogenic as determined by immunoglobulin G passive transfer animal models. More than 50% of pemphigus vulgaris sera also contain anti-desmoglein 1 autoantibodies; however, the pathogenicity of the anti-desmoglein 1 autoantibodies in pemphigus vulgaris remains unknown. In this study, we used soluble recombinant extracellular domains of desmoglein 1 and desmoglein 3 to obtain affinity-purified anti-desmoglein 1 and anti-desmoglein 3 autoantibodies from pemphigus vulgaris sera and examined the pathogenicity of each fraction separately using the passive transfer mouse model. By immunoprecipitation, the purified anti-desmoglein 1 and anti-desmoglein 3 showed no cross-reactivity. The anti-desmoglein 1 autoantibodies in pemphigus vulgaris induced typical pemphigus foliaceus lesions in neonatal mice, whereas the anti-desmoglein 3 fraction induced pemphigus vulgaris-like lesions. In addition, the pathogenic anti-desmoglein 1 and anti-desmoglein 3 autoantibodies in pemphigus vulgaris had predominant IgG4 subclass specificity. These findings suggest that the anti-desmoglein 1 antibodies in pemphigus vulgaris are pathogenic