Temperature Influence on Pseudothecia Development Stages of Venturia inaequalis in the Western Cape of South Africa.

Pseudothecia development stages of Venturia inaequalis (apple scab) were investigated in two climatically different regions in the Western Cape of South Africa. The aim was to determine the pseudothecial density (PD; pseudothecia per fertile lesion [p/f]) and ascal density (AD; asci per pseudothecium [a/p]) that contributes to defining the potential ascospore dose in a common prediction model of the apple scab infection risk. The PD and AD were compared between Elgin (EL), now considered a warm winter apple-growing region because of climate warming, and Koue Bokkeveld (KB), a cold winter region. In 2012 and 2013, scabbed apple leaves were collected during leaf-drop in KB and EL and overwintered either in their region of origin or in the other region. PD was significantly higher in scabbed leaves collected and overwintered in KB (mean, 24.11 p/f) than in leaves collected in KB and overwintered in EL (mean, 17.11 p/f; P < 0.001). PD of scabbed leaves collected and overwintered in EL (mean, 15.27 p/f) or collected in EL and overwintered in KB (mean, 16.07 p/f) did not differ significantly. Ascal density did not differ significantly in any treatment or season. We concluded that the significantly higher PD of scabbed leaves collected from the cooler region of KB and overwintered in KB compared with scabbed leaves collected in EL or KB and overwintered in EL could be caused by adaptations of V. inaequalis populations to the respective climates. This implied long-term effects of climate warming on apple scab epidemiology and management.

Genetic Diversity and Gene Flow of Four South African Venturia inaequalis (Apple Scab) Populations.

Venturia inaequalis isolates were collected during the 2012/13 and 2013/14 seasons from the four principal apple growing regions of South Africa, Elgin (n = 114), Koue Bokkeveld (n = 126), Lower Langkloof (n = 92), and Upper Langkloof (n = 103). Sequence analysis of the ribosomal internal transcribed spacer (ITS) gene regions and genotyping with six (2012/13) and seven (2013/14) microsatellite (SSR) markers was conducted. A subset of 12 isolates from the individual ITS haplotype groups were sequenced for the translation elongation factor-1 alpha (TEF1) and the large subunit of the RNA polymerases II (RPB1) gene regions. Four haplotypes were found for ITS, whereas all isolates were identical for the TEF1 and RPB1 gene regions. The SSR markers revealed considerable variation with an average gene diversity (H) of 0.675. Multivariate analysis (discriminant analysis of principal components [DAPC]) revealed that the two Langkloof populations clustered together with the Koue Bokkeveld population. The population from the warmer winter region, Elgin, clustered separately from the rest of the populations (ΦPT = 0.076 to 0.116; P ≤ 0.05). Estimates of gene flow showed the highest migration rate from the Koue Bokkeveld, toward the Lower Langkloof (M = 151.1), and the least migration to and from the Elgin region (average M = 42.75). Occasionally, identical genotypes (clones) were detected across seasons in the Koue Bokkeveld and Elgin area, which might contribute to overwintering conidia. From this study, it is evident that South Africa most likely has V. inaequalis subpopulations linked to diverse climatic conditions of the coastal Elgin region compared with the mountainous inland regions of the Koue Bokkeveld and the Langkloof.

Outcome reporting in bariatric surgery: an in-depth analysis to inform the development of a core outcome set, the BARIACT Study.

Outcome reporting in bariatric surgery needs a core outcome set (COS), an agreed minimum set of outcomes reported in all studies of a particular condition. The aim of this study was to summarize outcome reporting in bariatric surgery to inform the development of a COS. Outcomes reported in randomized controlled trials (RCTs) and large non-randomized studies identified by a systematic review were listed verbatim and categorized into domains, scrutinizing the frequency of outcome reporting and uniformity of definitions. Ninety studies (39 RCTs) identified 1,088 separate outcomes, grouped into nine domains with most (n = 920, 85%) reported only once. The largest outcome domain was 'surgical complications', and overall, 42% of outcomes corresponded to a theme of 'adverse events'. Only a quarter of outcomes were defined, and where provided definitions, which were often contradictory. Percentage of excess weight loss was the main study outcome in 49 studies, but nearly 40% of weight loss outcomes were heterogeneous, thus not comparable. Outcomes of diverse bariatric operations focus largely on adverse events. Reporting is inconsistent and ill-defined, limiting interpretation and comparison of published studies. Thus, we propose and are developing a COS for the surgical treatment of severe and complex obesity.

Randomized clinical trial of intraoperative superficial cervical plexus block versus incisional local anaesthesia in thyroid and parathyroid surgery.

BACKGROUND: Moderate wound pain and opiate analgesia requirement is reported following thyroid and parathyroid surgery. A randomized clinical trial was performed to investigate whether intraoperative superficial cervical plexus block (SCPB) would decrease postoperative pain and analgesia use. METHODS: Patients were randomized to incisional local anaesthesia (control) or incisional local anaesthesia plus intraoperative SCPB. The primary outcome measure was pain, assessed by a visual analogue scale (VAS). Secondary outcome measures were analgesia use (strong opiates defined as having potency at least as strong as that of oral morphine), respiratory rate and sedation score. Primary outcome measures were analysed with non-parametric tests, as well as with receiver operating characteristic (ROC) curves calculated as area under the curve (AUC) to discriminate between trial limbs. RESULTS: Twenty-nine patients were randomized to each group. Pain (VAS) scores were lower in patients who received intraoperative SCPB than in controls 30 min after surgery and subsequently (P < 0·020 at all time points), with a median pain score of zero on the day of operation in the SCPB group. Corresponding analysis of ROC curves showed differences between groups at 30 min (AUC = 0·722, P = 0·012), 90 min (AUC = 0·747, P = 0·005), 150 min (AUC = 0·803, P < 0·001) and 210 min (AUC = 0·849, P < 0·001) after surgery, and at 07.00 hours on postoperative day 1 (AUC = 0·710, P = 0·017). Fewer patients in the SCPB group required strong opiates (5 of 29 versus 16 of 29 in the control group; P = 0·003) and rescue opiates (6 of 29 versus 20 of 29; P < 0·001). CONCLUSION: Intraoperative SCPB reduces pain scores following thyroid and parathyroid surgery, and reduces the requirement for strong and rescue opiates. REGISTRATION NUMBER: 2009-012671-98 (https://www.clinicaltrialsregister.eu).

Trans-anal rectoscopic ball diathermy (TARD) for radiotherapy-induced haemorrhagic telangiectasia: a safe and effective treatment.

AIM: Rectal bleeding may occur late after radiotherapy for prostate or bladder cancer, particularly when given by external beam, due to radiotherapy-induced haemorrhagic telangiectasia (RIHT). We present the results of trans-anal rectoscopic ball diathermy (TARD) for RIHT. METHOD: Data were collected from patients who received TARD for RIHT. The diagnosis was made during endoscopic examination. Treatment involved discretely spaced spot monopolar diathermy coagulation of the rectal mucosa to the affected areas. RESULTS: Thirteen patients [median age 76 (69-80) years] underwent TARD for RIHT between 2005 and 2008. All presented late with rectal bleeding following radiotherapy for prostate or bladder cancer. Eight were treated as a day case, four remained in hospital for one night and one was hospitalized for 2 days. There was no mortality. Eleven patients achieved excellent symptomatic control requiring no further treatment at a median follow-up of 20 (3-36) months. One patient underwent further TARD for recurrence. One patient complained of severe anorectal pain of no obvious cause and one developed constipation. CONCLUSION: Trans-anal rectoscopic ball diathermy (TARD) is a safe and effective treatment for patients with rectal bleeding due to RIHT.

Delayed presentation of vernix caseosa peritonitis.

INTRODUCTION: Vernix caseosa peritonitis (VCP) is a rare and poorly recognised condition resulting from a sustained foreign body reaction to the vernix caseosa of the baby. This case-based review aims to highlight its importance for any medical team managing patients with peritonitis who have undergone a recent Caesarean section. CASE REPORT: A 31-year-old woman presented 5 weeks after a Caesarean section with symptoms and signs of peritonitis. CONCLUSIONS: Laparotomy and peritoneal lavage is the mainstay of treatment for VCP. Knowledge of the condition may stop inadvertent resection of normal intra-abdominal organs. Greater awareness of VCP is required to ensure earlier recognition as patients can recover well following timely operative intervention.

In vitro cytokine production and growth inhibition of lymphoblastoid cell lines by CD4+ T cells from Epstein-Barr virus (EBV) seropositive donors.

In vitro stimulation of peripheral blood lymphocytes (PBL) from healthy Epstein-Barr Virus (EBV) seropositive individuals with autologous lymphoblastoid cell lines (LCL) gives rise to CD4+ and CD8+ T cells both of which are cytotoxic for autologous lymphoblastoid cells. Activated EBV-specific CD4+ T cells are cytotoxic towards autologous LCL but, paradoxically, CD4+ T cells have also been shown to enhance tumour formation in SCID/Hu mice. Here, we show that despite being cytotoxic, CD4+ T-cell lines from different donors show considerable variation in their ability to inhibit the long-term growth of autologous LCLs in vitro. Following re-stimulation in vitro with PMA and ionomycin, CD4+ T cells produced IFNgamma, TNFalpha, TNFbeta, IL-2, IL-4, IL-10 and IL-13. TNFalpha, TNFbeta and IL-10 production were also detected in LCL. IL-6 was only detected in trace amounts in either cell type. The ratio of IFNgamma to IL-4 production varied between the CD4+ T-cell lines, indicating differences in the Th1/Th2 balance of the response. When CD4+ T cells were re-stimulated using autologous LCL as antigen-presenting cells, they produced more IL-4 and less IFNgamma or IL-13 when compared with cells re-stimulated by phorbol myristate acetate (PMA) and ionomycin. Using two colour cytokine staining, we showed that many individual CD4+ T cells produced IFNgamma along with either IL-4 or IL-13. Purified CD4+ T cells completely inhibited the outgrowth of autologous LCL in five out of nine cases, and partially inhibited outgrowth in the remaining four. There was no correlation between the pattern of CD4+ T-cell cytokine production and the capacity to inhibit outgrowth of autologous LCL. The killing of LCLs was contact-dependant and not mediated by soluble factors. We conclude that the ability of CD4+ T cells to inhibit autologous LCL growth is not directly related to T-helper cell cytokine production, but may depend on cytoxicity through surface ligands such as CD95L (FasL) and TNFalpha-related apoptosis-inducing ligand (TRAIL).

Kinetic, thermodynamic, and developmental consequences of deleting creatine kinase isoenzymes from the heart. Reaction kinetics of the creatine kinase isoenzymes in the intact heart.

Creatine kinase (CK) exists as a family of isoenzymes in excitable tissue. We studied isolated perfused hearts from mice lacking genes for either the main muscle isoform of CK (M-CK) or both M-CK and the main mitochondrial isoform (Mt-CK) to determine 1) the biological significance of CK isoenzyme shifts, 2) the necessity of maintaining a high CK reaction rate, and 3) the role of CK isoenzymes in establishing the thermodynamics of ATP hydrolysis. (31)P NMR was used to measure [ATP], [PCr], [P(i)], [ADP], pH, as well as the unidirectional reaction rate of PCr--> [gamma-P]ATP. Developmental changes in the main fetal isoform of CK (BB-CK) were unaffected by loss of other CK isoenzymes. In hearts lacking both M- and Mt-CK, the rate of ATP synthesis from PCr was only 9% of the rate of ATP synthesis from oxidative phosphorylation demonstrating a lack of any high energy phosphate shuttle. We also found that the intrinsic activities of the BB-CK and the MM-CK isoenzymes were equivalent. Finally, combined loss of M- and Mt-CK (but not loss of only M-CK) prevented the amount of free energy released from ATP hydrolysis from increasing when pyruvate was provided as a substrate for oxidative phosphorylation.

Cardiac hypertrophy with preserved contractile function after selective deletion of GLUT4 from the heart.

Glucose enters the heart via GLUT1 and GLUT4 glucose transporters. GLUT4-deficient mice develop striking cardiac hypertrophy and die prematurely. Whether their cardiac changes are caused primarily by GLUT4 deficiency in cardiomyocytes or by metabolic changes resulting from the absence of GLUT4 in skeletal muscle and adipose tissue is unclear. To determine the role of GLUT4 in the heart we used cre-loxP recombination to generate G4H(-/-) mice in which GLUT4 expression is abolished in the heart but is present in skeletal muscle and adipose tissue. Life span and serum concentrations of insulin, glucose, FFAs, lactate, and beta-hydroxybutyrate were normal. Basal cardiac glucose transport and GLUT1 expression were both increased approximately 3-fold in G4H(-/-) mice, but insulin-stimulated glucose uptake was abolished. G4H(-/-) mice develop modest cardiac hypertrophy associated with increased myocyte size and induction of atrial natriuretic and brain natriuretic peptide gene expression in the ventricles. Myocardial fibrosis did not occur. Basal and isoproterenol-stimulated isovolumic contractile performance was preserved. Thus, selective ablation of GLUT4 in the heart initiates a series of events that results in compensated cardiac hypertrophy.

Role of MgADP in the development of diastolic dysfunction in the intact beating rat heart.

Sarcomere relaxation depends on dissociation of actin and myosin, which is regulated by a number of factors, including intracellular [MgATP] as well as MgATP hydrolysis products [MgADP] and inorganic phosphate [Pi], pHi, and cytosolic calcium concentration ([Ca2+]c). To distinguish the contribution of MgADP from the other regulators in the development of diastolic dysfunction, we used a strategy to increase free [MgADP] without changing [MgATP], [Pi], or pHi. This was achieved by applying a low dose of iodoacetamide to selectively inhibit the creatine kinase activity in isolated perfused rat hearts. [MgATP], [MgADP], [Pi], and [H+] were determined using 31P NMR spectroscopy. The [Ca2+]c and the glycolytic rate were also measured. We observed an approximately threefold increase in left ventricular end diastolic pressure (LVEDP) and 38% increase in the time constant of pressure decay (P < 0.05) in these hearts, indicating a significant impairment of diastolic function. The increase in LVEDP was closely related to the increase in free [MgADP]. Rate of glycolysis was not changed, and [Ca2+]c increased by 16%, which cannot explain the severity of diastolic dysfunction. Thus, our data indicate that MgADP contributes significantly to diastolic dysfunction, possibly by slowing the rate of cross-bridge cycling.

On the dangers of adjusting the parameters values of mechanism-based mathematical models.

Mechanism-based mathematical models describe systems in terms of identifiable physical processes, and the parameters are assumed to have fundamental physical significance. Ideally, the parameter values are measured independent of the system being modeled, but these values are often adjusted to give the best fit of model predictions to experimental data. A systematic investigation of the effects of such parameter adjustment was conducted by developing a model system comprising a known reaction mechanism and known rate constants. Simulations of experiments were run, and then attempts were made to model the system under a variety of problematic, but realistic, conditions. (1) When one rate constant was seriously in error, adjustment of a different rate constant gave the greatest improvement in the model fit. (2) When a contaminant was present in the experiment, the effects could be hidden by the adjustment of the rate constants. (3) When an incorrect reaction mechanism was assumed, the error could be hidden by parameter adjustment if the concentrations of only one of the reacting species were considered or if an unweighted fit was used for the optimization. (4) Parameter values adjusted for one set of experimental conditions gave a poorer fit than did the unadjusted parameter values when attempting to model a new set of experimental condition (addition of an inhibitor). These results show the potential dangers of adjusting parameter values and the importance of measuring as many variables as possible in a complex system.