Frequency and severity of general surgical emergencies during the COVID-19 pandemic: single-centre experience from a large metropolitan teaching hospital.

INTRODUCTION: The COVID-19 pandemic has put significant stress on healthcare systems globally. This study focuses on emergency general surgery services at a major trauma centre and teaching hospital. We aimed to identify whether the number of patients and the severity of their presentation has significantly changed since the implementation of a national lockdown. MATERIALS AND METHODS: This study is a retrospective review of acute referrals (from general practice and accident and emergency) to the emergency general surgery team over a 14-day period before (group 1) and during (group 2) lockdown. RESULTS: A total of 151 patients were reviewed by the general surgical team in group 1 and 75 in group 2 (a 50.3% reduction). The number of days with symptoms prior to presentation was significantly shorter in group 1 compared with group 2 (3 vs 4, p = 0.04). There was no significant difference in the National Early Warning Score, white blood cell count, lymphocytes and C-reactive protein on admission between the two groups of patients. There were significantly fewer patients admitted after lockdown compared with pre-lockdown (66% vs 48%, p = 0.01). Length of hospital stay was significantly shorter during lockdown compared with pre-lockdown (5 days vs 4 days, p = 0.04). CONCLUSION: Fewer patients were referred and admitted during lockdown compared with pre-lockdown, and the length of stay was also significantly reduced. There was also a delay in presentation to hospital, although these patients were not more unwell based on the scoring criteria used within this study.

An analysis of workplace exposures to benzene over four decades at a petrochemical processing and manufacturing facility (1962-1999).

Benzene, a known carcinogen, can be generated as a by-product during the use of petroleum-based raw materials in chemical manufacturing. The aim of this study was to analyze a large data set of benzene air concentration measurements collected over nearly 40 years during routine employee exposure monitoring at a petrochemical manufacturing facility. The facility used ethane, propane, and natural gas as raw materials in the production of common commercial materials such as polyethylene, polypropylene, waxes, adhesives, alcohols, and aldehydes. In total, 3607 benzene air samples were collected at the facility from 1962 to 1999. Of these, in total 2359 long-term (>1 h) personal exposure samples for benzene were collected during routine operations at the facility between 1974 and 1999. These samples were analyzed by division, department, and job title to establish employee benzene exposures in different areas of the facility over time. Sampling data were also analyzed by key events over time, including changes in the occupational exposure limits (OELs) for benzene and key equipment process changes at the facility. Although mean benzene concentrations varied according to operation, in nearly all cases measured benzene quantities were below the OEL in place at the time for benzene (10 ppm for 1974-1986 and 1 ppm for 1987-1999). Decreases in mean benzene air concentrations were also found when data were evaluated according to 7- to 10-yr periods following key equipment process changes. Further, an evaluation of mortality rates for a retrospective employee cohort (n = 3938) demonstrated that the average personal benzene exposures at this facility (0.89 ppm for the period 1974-1986 and 0.125 ppm for the period 1987-1999) did not result in increased standardized mortality ratio (SMRs) for diseases or malignancies of the lymphatic system. The robust nature of this data set provides comprehensive exposure information that may be useful for assessing human benzene exposures at similar facilities. The data also provide a basis for comparable measured exposure levels and the potential for adverse health effects. These data may also prove beneficial for comparing relative exposure potential for production versus nonproduction operations and the relationship between area and personal breathing zone samples.

Massive gene decay in the leprosy bacillus.

Leprosy, a chronic human neurological disease, results from infection with the obligate intracellular pathogen Mycobacterium leprae, a close relative of the tubercle bacillus. Mycobacterium leprae has the longest doubling time of all known bacteria and has thwarted every effort at culture in the laboratory. Comparing the 3.27-megabase (Mb) genome sequence of an armadillo-derived Indian isolate of the leprosy bacillus with that of Mycobacterium tuberculosis (4.41 Mb) provides clear explanations for these properties and reveals an extreme case of reductive evolution. Less than half of the genome contains functional genes but pseudogenes, with intact counterparts in M. tuberculosis, abound. Genome downsizing and the current mosaic arrangement appear to have resulted from extensive recombination events between dispersed repetitive sequences. Gene deletion and decay have eliminated many important metabolic activities including siderophore production, part of the oxidative and most of the microaerophilic and anaerobic respiratory chains, and numerous catabolic systems and their regulatory circuits.

Analysis of 114 kb of DNA sequence from fission yeast chromosome 2 immediately centromere-distal to his5.

One hundred and fourteen kilobase pairs (kb) of contiguous genomic sequence have been determined immediately distal to the his5 genetic marker located about 0.9 Mb from the centromere on the long arm of Schizosaccharomyces pombe chromosome 2. The sequence is contained in overlapping cosmid clones c16H5, c12D12, c24C6 and c19G7, of which 20 kb are identical to previously reported sequence from clone c21H7. The remaining 93 781 bp of sequence contains 10 known genes (cdc14, cdm1, cps1, gpa1, msh2, pck2, rip1, rps30-2, sad1 and ubl1), 32 open reading frames (ORFs) capable of coding for proteins of at least 100 amino acid residues in length, one 5S rRNA gene, one tRNA(Pro) gene, one lone Tf1-type long terminal repeat (LTR) and one lone Tf2-type LTR. There is a density of one protein-coding gene per 2.2 kb and 22 of the 42 ORFs (52%) incorporate one or more introns. Twenty-one of the novel ORFs show sequence similarities which suggest functions of their products, including a cyclin C, a MADS box transcription factor, mad2-like protein, telomere binding protein, topoisomerase II-associated protein, ATP-dependent DEAH box RNA helicase, G10 protein, ubiquitin-activating e1-like enzyme, nucleoporin, prolyl-tRNA synthetase, peptidylprolyl isomerase, delta-1-pyrroline-5-carboxylate dehydrogenase, protein transport protein, coatomer epsilon, TCP-1 chaperonin, beta-subunit of 6-phosphofructokinase, aminodeoxychorismate lyase, a phosphate transport protein and a thioredoxin.

Complete DNA sequence of a serogroup A strain of Neisseria meningitidis Z2491.

Neisseria meningitidis causes bacterial meningitis and is therefore responsible for considerable morbidity and mortality in both the developed and the developing world. Meningococci are opportunistic pathogens that colonize the nasopharynges and oropharynges of asymptomatic carriers. For reasons that are still mostly unknown, they occasionally gain access to the blood, and subsequently to the cerebrospinal fluid, to cause septicaemia and meningitis. N. meningitidis strains are divided into a number of serogroups on the basis of the immunochemistry of their capsular polysaccharides; serogroup A strains are responsible for major epidemics and pandemics of meningococcal disease, and therefore most of the morbidity and mortality associated with this disease. Here we have determined the complete genome sequence of a serogroup A strain of Neisseria meningitidis, Z2491. The sequence is 2,184,406 base pairs in length, with an overall G+C content of 51.8%, and contains 2,121 predicted coding sequences. The most notable feature of the genome is the presence of many hundreds of repetitive elements, ranging from short repeats, positioned either singly or in large multiple arrays, to insertion sequences and gene duplications of one kilobase or more. Many of these repeats appear to be involved in genome fluidity and antigenic variation in this important human pathogen.

The complete nucleotide sequence of chromosome 3 of Plasmodium falciparum.

Analysis of Plasmodium falciparum chromosome 3, and comparison with chromosome 2, highlights novel features of chromosome organization and gene structure. The sub-telomeric regions of chromosome 3 show a conserved order of features, including repetitive DNA sequences, members of multigene families involved in pathogenesis and antigenic variation, a number of conserved pseudogenes, and several genes of unknown function. A putative centromere has been identified that has a core region of about 2 kilobases with an extremely high (adenine + thymidine) composition and arrays of tandem repeats. We have predicted 215 protein-coding genes and two transfer RNA genes in the 1,060,106-base-pair chromosome sequence. The predicted protein-coding genes can be divided into three main classes: 52.6% are not spliced, 45.1% have a large exon with short additional 5' or 3' exons, and 2.3% have a multiple exon structure more typical of higher eukaryotes.

Prevalence of hypertension in a hemodialysis population.

BACKGROUND: Accurate information on prevalence and status of blood pressure (BP) control in hemodialysis patients is lacking. Our Hemodialysis Quality Improvement Program, sought to determine: 1) The extent and control of hypertension (HTN), 2) whether Erythropoietin (EPO) dose or intradialytic fluid loss had any effect on BP and 3) a means to follow the severity of HTN. PATIENTS AND METHODS: The pre/post mid-week dialysis BP readings of 190 patients (64+/-14.1 years, 53% males, 77% whites) were evaluated over a 3 month period. HTN was defined as BP >150/90. Hypertension was further characterized according to whether the patients had normal or elevated pre-dialysis systolic, pre-dialysis diastolic, post-dialysis systolic or post-diastolic BP readings on more than 6 of the possible 13 recordings. The average EPO dose and weight loss during dialysis was correlated with BP. To better understand the extent of HTN, systolic and diastolic pressures were separately graded from 0 to 3 and a number designated as hypertension sensitivity index (HSI) was assigned to each patient. RESULTS: Of the 190 patients, 146 (76.8%) were hypertensive. 117 out of 146 hypertensive patients (80.1%) had persistent elevation of BP despite being on one or more antihypertensive medications. Most patients were on calcium channel blockers (39%) with 27% being on beta-blockers and 14% on Angiotensin converting enzyme inhibitors. There was no correlation between the number of medications used and the control of HTN. The dose of EPO also had no effect on the degree of HTN. 69.8% of all HTN was systolic. Of this, 64.7% was pre-dialysis and 35.3% post-dialysis. Multiple regression analysis demonstrated a significant correlation with loss of weight during dialysis and lowering of systolic BP (r = 0.33, p = 0.0001). The mean HSI for this population was 2.3+/-1.8. CONCLUSION: HTN was a frequent finding in our hemodialysis population and it was controlled in only 19.9% of hypertensive patients. Most of this HTN was pre-dialysis systolic. There was a significant correlation between fluid loss during dialysis and lowering of blood pressure. The use of the HSI has proven to be helpful in differentiating type and severity of HTN.

Deciphering the biology of Mycobacterium tuberculosis from the complete genome sequence.

Countless millions of people have died from tuberculosis, a chronic infectious disease caused by the tubercle bacillus. The complete genome sequence of the best-characterized strain of Mycobacterium tuberculosis, H37Rv, has been determined and analysed in order to improve our understanding of the biology of this slow-growing pathogen and to help the conception of new prophylactic and therapeutic interventions. The genome comprises 4,411,529 base pairs, contains around 4,000 genes, and has a very high guanine + cytosine content that is reflected in the biased amino-acid content of the proteins. M. tuberculosis differs radically from other bacteria in that a very large portion of its coding capacity is devoted to the production of enzymes involved in lipogenesis and lipolysis, and to two new families of glycine-rich proteins with a repetitive structure that may represent a source of antigenic variation.

The nucleotide sequence of Saccharomyces cerevisiae chromosome IX.

Large-scale systematic sequencing has generally depended on the availability of an ordered library of large-insert bacterial or viral genomic clones for the organism under study. The generation of these large insert libraries, and the location of each clone on a genome map, is a laborious and time-consuming process. In an effort to overcome these problems, several groups have successfully demonstrated the viability of the whole-genome random 'shotgun' method in large-scale sequencing of both viruses and prokaryotes. Here we report the sequence of Saccharomyces cerevisiae chromosome IX, determined in part by a whole-chromosome 'shotgun', and describe the particular difficulties encountered in the random 'shotgun' sequencing of an entire eukaryotic chromosome. Analysis of this sequence shows that chromosome IX contains 221 open reading frames (ORFs), of which approximately 30% have been sequenced previously. This chromosome shows features typical of a small Saccharomyces cerevisiae chromosome.

The nucleotide sequence of Saccharomyces cerevisiae chromosome XIII.

Systematic sequencing of the genome of Saccharomyces cerevisiae has revealed thousands of new predicted genes and allowed analysis of long-range features of chromosomal organization. Generally, genes and predicted genes seem to be distributed evenly throughout the genome, having no overall preference for DNA strand. Apart from the smaller chromosomes, which can have substantially lower gene density in their telomeric regions, there is a consistent average of one open reading frame (ORF) approximately every two kilobases. However, one of the most surprising findings for a eukaryote with approximately 6,000 genes was the amount of apparent redundancy in its genome. This redundancy occurs both between individual ORFs and over more extensive chromosome regions, which have been duplicated preserving gene order and orientation. Here we report the entire nucleotide sequence of chromosome XIII, the sixth-largest S. cerevisiae chromosome, and demonstrate that its features and organization are consistent with those observed for other S. cerevisiae chromosomes. Analysis revealed 459 ORFs, 284 have not been identified previously. Both intra- and interchromosomal duplications of regions of this chromosome have occurred.

Pregnancy complicated by acute renal failure requiring hemodialysis.

The goal of a successful, full-term vaginal birth of a healthy infant was achieved while avoiding acidosis, hyperkalemia, and fluid overload in this pregnant patient with ARF. Acting in a prudent manner to prevent potential life-threatening complications was of paramount importance in this patient whose etiology of renal failure was uncertain. In the case of the pregnant patient, an ultrasound may not be as valuable a diagnostic tool when the enlarged gravid uterus cannot allow complete visualization of the ureters. Interdepartmental collaboration in the case of this challenging patient resulted in a mutual learning experience, while ensuring a safe delivery for both mother and child. Additionally, by working together, the professional staff enhanced the patient's ability to meet the expected outcomes.

The children's hearing system and the health visitor's role.

Scotland's legal system is widely acknowledged to deal more sensitively with child protection cases. Here Karen Devlin describes the children's hearing system and discusses the role of the health visitor working with families in crisis and coming before a panel hearing.