Early vs. standard reversal ileostomy: a systematic review and meta-analysis.

BACKGROUND: Formation of a defunctioning loop ileostomy is common after mid and low rectal resection. Historically, they were reversed between 3 and 6 months after initial resection. Recently, earlier closure (< 14 days) has been suggested by some current randomised controlled trials. The aim of this study was to investigate the effect of early stoma closure on surgical and patient outcomes. METHODS: A systematic review of the current randomised controlled trial literature comparing early and standard ileostomy closure after rectal surgery was performed. Specifically, we examined surgical outcomes including; morbidity, mortality and quality of life. RESULTS: Six studies met the predefined criteria and were included in our analysis. 275 patients underwent early stoma closure compared with 259 patients having standard closure. Overall morbidity was similar between both groups (25.5% vs. 21.6%) (OR, 1.47; 95% CI 0.75-2.87). However, there tended to be more reoperations (8.4 vs. 4.2%) (OR, 2.02, 95% CI 0.99-4.14) and small bowel obstructions/postoperative ileus (9.3% vs. 4.4%) (OR 0.44, 95% CI 0.22-0.90) in the early closure group, but no difference across the other domains. CONCLUSIONS: Early closure appears to be a feasible in highly selective cases after good perioperative counselling and shared decision-making. Further research on quality of life outcomes and long term benefits is necessary to help define which patients are suitable candidates for early closure.

Endobronchial valve use in COVID-19 related pneumothorax and persistent air leak.

Pneumothoraces may occur rarely in coronavirus (COVID-19) patients, often resulting from a combination of fibrotic parenchymal changes and prolonged high-pressure ventilation. Very few studies have been published describing the management of pneumothorax in the novel COVID-19 pneumonia patients. Although chest drain insertion represents the first line of treatment, a persistent pneumothorax and air leak requiring intervention could be managed by a thoracoscopic procedure or, as is the case here, by endobronchial valve insertion. Endobronchial valve insertion is a minimally invasive technique that provides a treatment option in patients with severe parenchymal COVID-19 related lung disease. As far as the authors are aware this is the first report of the use of endobronchial valves in a COVID-19 patient.

Lateral pelvic lymphadenectomy for low rectal cancer: a META-analysis of recurrence rates.

BACKGROUND: Locoregional recurrence (LR) remains a problem for patients with lower rectal cancer despite standardized surgery and improved neoadjuvant treatment regimens. Lateral pelvic lymph node dissection (LPLND) has been routine practice for some time in the Orient/East, but other regions have concerns about morbidity. As perioperative care and surgical approaches are refined, this has been revisited for selected patients. The question as to whether LPLND improves oncological outcomes was explored here. METHODS: A systematic review of patients who underwent TME with or without LPLND from 2000 to 2020 was performed. The primary endpoint was the rate of LR between the two groups. RESULTS: Seven papers met the predefined search criteria in which 2000 patients underwent TME alone, while 1563 patients had TME and LPLND. The rate of LR was marginally higher with TME alone when compared with TME plus LPLND, but this result was not statistically significant (9.8 vs 9.4%, odds ratio 0.75, 95% CI 0.41-1.38, *p = 0.35). In addition, four studies reported on distant recurrence rates, with TME and LPLND showing a slight reduction in overall rates (27.3 vs 29.9%, respectively, OR 0.65, 95% CI 0.45-0.92, *p = 0.02). CONCLUSION: The addition of LPLND to TME is not associated with a significantly lower risk of LR in patients who undergo surgery for lower rectal cancer.

Should MRI Be the Imaging Modality of Choice in Suspected Appendicitis During Pregnancy?

Aim The aim of this review was to evaluate the efficacy of magnetic resonance imaging (MRI) in determining appendicitis during pregnancy. Methods We retrospectively reviewed the clinical course for all pregnant patients with suspected appendicitis from 2013-2018. We evaluated the efficacy of MRI and Alvarado scoring and its impact on management. Results Twenty-nine pregnant patients with suspected appendicitis had an MRI. The majority (90%, n=26/29) had normal diagnostics with two patients (10.3%) having findings consistent with acute appendicitis. Two other patients proceeded to laparoscopy, one with an inconclusive MRI, and one patient with clinical appendicitis. We found no accurate correlation between pregnancy and Alvarado scoring. Conclusion MRI is a safe adjunct in accurately diagnosing appendicitis in pregnancy. Its routine use could help reduce rates of negative appendectomies and the potential risk to maternal and fetal health.

Protein annotation and modelling servers at University College London.

The UCL Bioinformatics Group web portal offers several high quality protein structure prediction and function annotation algorithms including PSIPRED, pGenTHREADER, pDomTHREADER, MEMSAT, MetSite, DISOPRED2, DomPred and FFPred for the prediction of secondary structure, protein fold, protein structural domain, transmembrane helix topology, metal binding sites, regions of protein disorder, protein domain boundaries and protein function, respectively. We also now offer a fully automated 3D modelling pipeline: BioSerf, which performed well in CASP8 and uses a fragment-assembly approach which placed it in the top five servers in the de novo modelling category. The servers are available via the group web site at http://bioinf.cs.ucl.ac.uk/.

FFPred: an integrated feature-based function prediction server for vertebrate proteomes.

One of the challenges of the post-genomic era is to provide accurate function annotations for large volumes of data resulting from genome sequencing projects. Most function prediction servers utilize methods that transfer existing database annotations between orthologous sequences. In contrast, there are few methods that are independent of homology and can annotate distant and orphan protein sequences. The FFPred server adopts a machine-learning approach to perform function prediction in protein feature space using feature characteristics predicted from amino acid sequence. The features are scanned against a library of support vector machines representing over 300 Gene Ontology (GO) classes and probabilistic confidence scores returned for each annotation term. The GO term library has been modelled on human protein annotations; however, benchmark performance testing showed robust performance across higher eukaryotes. FFPred offers important advantages over traditional function prediction servers in its ability to annotate distant homologues and orphan protein sequences, and achieves greater coverage and classification accuracy than other feature-based prediction servers. A user may upload an amino acid and receive annotation predictions via email. Feature information is provided as easy to interpret graphics displayed on the sequence of interest, allowing for back-interpretation of the associations between features and function classes.

GH responsiveness in a large multinational cohort of SGA children with short stature (NESTEGG) is related to the exon 3 GHR polymorphism.

OBJECTIVE: The polymorphic deletion of exon 3 of the GH receptor (d3-GHR) has recently been linked to the magnitude of growth response to recombinant human GH (rhGH) therapy in short children with or without GH deficiency. We investigated this association in a large multinational cohort from the Network of European Studies of Genes in Growth (NESTEGG), comprising short children born small for gestational age (SGA). DESIGN: The study included short prepubertal SGA children treated with rhGH for 1 or 2 years. POPULATION: Two hundred and forty white Caucasian SGA children (138 male, 102 female) aged 6.6 +/- 2.3 years with a height at -3.0 +/- 0.7 SDS at start of rhGH treatment; 193 ethnically matched controls. METHODS: The GHR polymorphism (fl/fl, fl/d3 or d3/d3) was genotyped by polymerase chain reaction (PCR) multiplex assay. Growth velocity (G/V) in cm/year and changes in GV during the first and second year of rhGH treatment were evaluated. RESULTS: The change in GV was significantly greater in SGA children carrying one or two copies of the d3-GHR allele (P = 0.038 for the first year and P = 0.041 for the second year of GH treatment), but the change in height was not significantly different. Birthweight was significantly lower in SGA children with the d3/d3 genotype than in SGA children with the fl/fl genotype (P = 0.034) and in those with the fl/d3 genotype (P = 0.016). CONCLUSION: Our data, based on a large cohort, showed that the exon 3 GHR polymorphism is associated with responsiveness to rhGH treatment in SGA children with short stature.

Cosegregation of a novel homozygous CYP11B1 mutation with the phenotype of non-classical congenital adrenal hyperplasia in a consanguineous family.

We report a novel missense mutation of CYP11B1 causing non-classical 11beta-hydroxylase deficiency in 3 members of a consanguineous Turkish family. Two siblings presented with clinical evidence of precocious pseudopubarche. Biochemistry suggested 11beta-hydroxylase deficiency and genetic analysis revealed that they were homozygous for the missense mutation L489S within exon 9 of the CYP11B1 gene. The unaffected parents were heterozygotes for the same mutation. In addition, a paternal aunt of the affected siblings presenting with primary infertility and mild hirsutism was found to have the same homozygous mutation. This is the first report of a homozygous mutation in non-classical congenital adrenal hyperplasia that cosegregates with clinical phenotype. The significance of the missense mutation L489S in CYP11B1 is further supported by the conservation of leucine at position 489 in CYP11 genes in eleven other species. Molecular modelling of the enzyme suggests that the mutation L489S in CYP11B1 may alter the enzyme's substrate-binding affinity. These findings suggest that this homozygous mutation affects 11beta-hydroxylase function, resulting in the clinical features of non-classical adrenal hyperplasia in this family.

Monoclonal antibodies to human A-I apolipoprotein and characterisation of cyanogen bromide fragments of apoA-I.

Several monoclonal antibodies to human A-I apolipoprotein were produced after immunising mice with pure delipidated apoA-I. These monoclonal antibodies were characterised for their ability to react with whole lipoproteins, apolipoproteins and fragments of apoA-I generated by cleavage with cyanogen bromide. The data suggest that production of monoclonal antibodies using apoA-I as antigen was influenced by two major epitopes subsequently localised to cyanogen bromide fragments 1 and 3, and have been designated antibodies 1----5 A-IB and 6----10 A-IB, respectively. Cyanogen bromide fragments were first purified to homogeneity before screening by competitive displacement or immunoblotting procedures. Definitive characterisation of one antibody series (1----5 A-IB) depended ultimately on Western blotting following isoelectric focusing of purified apoA-I fragments. This technique identified the epitope for these antibodies to fragment 1, an identification not fully concluded from competitive displacement studies. These studies have also revealed the presence of microheterogeneity in fragment 1 (as well as in fragment 4) of apoA-I, suggesting that structural variations in several regions may account for the polymorphism observed in this apolipoprotein.

Population distributions of phenylbutazone and oxyphenbutazone after oral and i.v. dosing in horses.

Experiments to determine the residual plasma concentrations of phenylbutazone and its metabolites found in horses racing on a 'no-race day medication' or 24-h rule were carried out. One dosing schedule (oral-i.v.) consisted of 8.8 mg/kg (4 g/1000 lbs) orally for 3 days, followed by 4.4 mg/kg (2 g/1000 lbs) intravenously on day 4. A second schedule consisted of 4.4 mg/kg i.v. for 4 days. The experiments were carried out in Thoroughbred and Standardbred horses at pasture, half-bred horses at pasture, and in Thoroughbred horses in training. After administering the i.v. schedule for 4 days to Thoroughbred and Standardbred horses at pasture, the mean plasma concentrations of phenylbutazone increased from 0.77 microgram/ml on day 2 to 2.5 micrograms/ml on day 5. The shape of the frequency distribution of these populations was log-normal. These data are consistent with one horse in 1,000 yielding a plasma level of 8.07 micrograms/ml on day 5. After administration of the oral-i.v. schedule to Thoroughbred and Standardbred horses at pasture, the mean plasma concentrations of phenylbutazone were 3.4 micrograms/ml on day 2 and 3.5 micrograms/ml on day 5. The range on day 5 was from 1.4 to 8.98 micrograms/ml and the frequency distribution was log-normal. These data are consistent with one horse in 1000 having a plasma level of 15.8 micrograms/ml on day 5. In a final experiment, the oral dosing schedule was administered to 62 Thoroughbred horses in training. Plasma concentrations on day 5 in these horses averaged 5.3 micrograms/ml. The range was from 1.3 to 13.6 micrograms/ml and the frequency distribution was log-normal. Statistical projection of these values suggests that following this oral dosing schedule in racing horses about one horse in 1000 will yield a plasma level of 23.5 micrograms/ml of phenylbutazone 24 h after the last dose.

The effects of naloxone on endotoxic and hemorrhagic shock in horses.

The effects of naloxone on the cardiovascular, hematologic and metabolic derangements associated with endotoxic and hemorrhagic shock were studied in unanesthetized horses. In the first of 3 experiments blood glucose and lactate levels, hematocrit, white, red and differential white cell counts, rectal temperature and clinical signs were obtained before and after endotoxin (10 micrograms/Kg) administration in 5 horses. In the second experiment, two groups of 3 horses received either intravenous naloxone (0.04 mg/Kg) or saline, 7 minutes prior to endotoxin. In a third experiment two groups of 4 horses received either saline or naloxone (0.20 mg/Kg) immediately following acute hemorrhage. In the second and third experiments, pulse, mean arterial and right ventricular pressures, and heart rate were also observed. Endotoxin and acute hemorrhage produced hypothermia, leukopenia, lymphopenia, neutropenia, elevations in hematocrit, blood glucose and blood lactate, and clinical signs of shock. Naloxone (0.040 mg/Kg IV) significantly lowered endotoxin-induced increases in right ventricular pressure and heart rate, and at a higher dose (0.20 mg/Kg) antagonized the decrease in pulse and heart rate, and tachycardia observed after acute hemorrhage. These results suggest endogenous opioids are involved in the pathogenesis of shock. Naloxone appeared to attenuate some of the cardiovascular responses associated with shock and thus may be of therapeutic value in shock management.

The pharmacology of furosemide in the horse. V. Pharmacokinetics and blood levels of furosemide after intravenous administration.

Studies were undertaken to determine blood levels of furosemide in horses after 0.5- and 1.0-mg/kg doses administered iv. Analyses indicated that the pharmacokinetic parameters were dose independent and best described by a three-compartment open model. The alpha-, beta-, and gamma-phase half-lives of 5.6, 22.3, and 158.5 min, respectively, were observed after the 0.5-mg/kg dose. Similarly, the respective half-lives after the 1.0-mg/kg dose were 5.8, 24.1, and 177.2 min. After a 0.5-mg/kg dose of furosemide, population frequency distributions were evaluated at 1 hr and 4 hr post-drug administration. At 1 hr after dosing, the blood levels of furosemide in 30 horses were normally distributed. The mean plasma level was 97.9 ng/ml with a range of 41.9 ng/ml to 155.8 ng/ml and a SD of 25.0 ng/ml. Analyses of blood levels of furosemide in 47 horses at 4 hr after drug administration indicated that the population distribution was better fit by a normal curve after log transformation of the values. The mean plasma level at 4 hr post-dosing was 9.6 ng/ml with a range of 4.0 ng/ml to 19.4 ng/ml and a SD of 3.1 ng/ml. Based on this population distribution of the plasma levels, the probability of finding furosemide plasma concentrations above 24.6 ng/ml at 4 hr after anti-epistaxis dose was estimated at less than 1 in 1000.

Pharmacokinetics and protein binding of morphine in horses.

Morphine could be detected in horses dosed with 0.1 mg of drug/kg of body weight for up to 48 hours in blood and 144 hours in urine. This dose of morphine elicited no observable effects and is a suggested analgesic dose. Computer analysis revealed that a 3-compartment open system was the best fitting model with a serum half life (t1/2(beta)) of 87.9 minutes and a urine t1/2(beta) of 101.1 minutes. Binding to equine serum proteins was linear over a drug concentration range of 3.88 X 10(-5)M to 3.50 X 10(-8)M and averaged 31.6%. In RBC-partitioning experiments, 78.1% of the drug was found in the plasma fraction. The data indicated that a horse should not be given morphine closer than 1 week before a race.

Effects of enkephalins versus opiates on locomotor activity of the horse.

The enkephalins are small, pentapeptide neurotransmitter molecules which have reportedly been used in racing horses. In our experiments, D-Ala2-Metenkephalinamide and leucine enkephalin were administered to horses intravenously (IV) and intracisternally (IC). Leucine enkephalin had little effect on locomotor activity by either route at doses of 0.01 mg/Kg or less. Methionine enkephalinamide, an enzyme resistant enkephalin analog, had no significant effect when given IV (0.002 and 0.008 mg/kg). Other experiments involving intracisternal dosing with this long acting form at higher levels (0.005-.011 mg/Kg), elicited an initial increase in locomotor activity, a rise in temperature, a marked increase in blood pressure, hyperventilation, the appearance of a rapid eye blinking reflex, lack of coordination and quivering. In contrast, dosing with fentanyl either IV (0.01) mg/Kg) or Ic (0.0002 mg/Kg) produced a tenfold increase in locomotor activity without accompanying adverse clinical symptoms. The data suggest that very large doses of IV administered enkephalins or their analogs may be necessary to increase locomotor activity but such doses may also elicit a number of less desirable side effect.

Morphine glucuronide hydrolysis: superiority of beta-glucuronidase from Patella vulgata.

beta-Glucuronidase from Patella vulgata, Helix aspersa, Helix pomatia, and bovine liver were evaluated for usefulness in routine hydrolysis of drug-glucuronic acid conjugates from equine urine samples. Factors affecting the reaction rate (enzyme concentration, ligand concentration, temperature, and pH) were optimized. A 3-h incubation at 65 degrees C with 5000 U of beta-glucuronidase from P. vulgata per milliliter of urine resulted in complete hydrolysis of all morphine glucuronide in the urine samples. Not only was the enzyme preparation from P. vulgata the most cost-effective beta-glucuronidase source studied, but also its thermal stability is such that it can be used at a temperature high enough to substantially shorten the incubation interval. Preliminary work on other drugs that form glucuronide conjugates indicates that this same procedure is similarly superior for use in their hydrolysis.

Furosemide, Patella vulgata beta-glucuronidase and drug analysis: conditions for enhancement of the TLC detection of apomorphine, butorphanol, hydromorphone, nalbuphine, oxymorphone and pentazocine in equine urine.

We have investigated the action of five sources of beta-glucuronidase enzymes on the hydrolysis of glucuronides of apomorphine, butorphanol, hydromorphone, nalbuphine, oxymorphone and pentazocine in equine urine. For all glucuronides tested, Patella vulgata beta-glucuronidase yielded the largest thin layer chromatographic (TLC) spots. For oxymorphone, P. vulgata was the only treatment to yield detectable TLC spots under test parameters. For these six drugs, TLC spot size and chromatographic quality were compared between control horses and horses pretreated with furosemide four hours earlier. Furosemide pretreatment produced a statistically significant increase in spot size and was found to enhance chromatogram quality. These findings support previous suggestions that P. vulgata is a superior drug-glucuronide hydrolyzing enzyme. They also support earlier reports that administration of furosemide at four hours pre-race is unlikely to result in significant interference with routine drug testing procedures.