Generation of LexA enhancer-trap lines in Drosophila by an international scholastic network

Conditional gene regulation in Drosophila through binary expression systems like the LexA-LexAop system provides a superb tool for investigating gene and tissue function. To increase the availability of defined LexA enhancer trap insertions, we present molecular, genetic, and tissue expression studies of 301 novel Stan-X LexA enhancer traps derived from mobilization of the index SX4 line. This includes insertions into distinct loci on the X, II, and III chromosomes that were not previously associated with enhancer traps or targeted LexA constructs, an insertion into ptc, and seventeen insertions into natural transposons. A subset of enhancer traps was expressed in CNS neurons known to produce and secrete insulin, an essential regulator of growth, development, and metabolism. Fly lines described here were generated and characterized through studies by students and teachers in an international network of genetics classes at public, independent high schools, and universities serving a diversity of students, including those underrepresented in science. Thus, a unique partnership between secondary schools and university-based programs has produced and characterized novel resources in Drosophila, establishing instructional paradigms devoted to unscripted experimental science.

The Impact of COVID Restrictions Among Rates of Falling in Assisted Living Residents

As a result of the COVID-19 pandemic, assisted living group activities and congregate dining stopped and residents were confined to their rooms. While this may have kept residents safer from contracting the virus, it also reduced their physical activity levels. The aim of this study was to investigate if rates of falls in one assisted living community varied as a result of COVID-19 restrictions. We analyzed fall incident reports from n=155 residents from October 2019 to October 2020. Results showed a total of n=802 falls in the year-long period (range of 1-30 falls per resident; mean = 5.17; SD=5.6 in the 12 month period). The majority (65%) of falls occurred in resident rooms. 55% of falls occurred between 6am and 6pm. The primary cause of these falls was loss of balance (30%). Comparing falls that occurred 5 months pre-restriction (Oct 2019-Feb 2020) with 5 months post-restriction (April 2020-August 2021) showed non-significant differences between time periods (p=.59). However, analyzing rates of falls by month showed a range of 46 - 88 falls by month with the lowest number occurring in winter months and the peak number of falls occurring in both Oct 2019 and 2020. Despite the majority of falls occurring in resident rooms, Covid restrictions of room confinement did not appear to impact the prevalence of falls in this sample. However, the seasonal variation warrants further research and those in assisted living should consider seasonal variations and proactively implement policies to prevent falls during these times.

Can quantitative 18F-FDG PET/CT and serum cytokine analysis differentiate ARVC from cardiac sarcoidosis?

Background

Arrhythmogenic right ventricular cardiomyopathy (ARVC) and Cardiac Sarcoidosis (CS) may both cause malignant arrhythmia and sudden death, but differentiating the two can be difficult.

Purpose

To investigate the role of quantitative FDG PET/CT at distinguishing ARVC from CS, and explore whether addition of an inflammatory panel correlates with PET uptake, aiding diagnosis.

Methods

10 patients with CS, 10 with ARVC were enrolled. Participants were prospectively studied with PET/CT. LV uptake was quantified using software and a 17-segment model, measuring maximum standardised uptake (SUVmax) and mean myocardial uptake, comparing these to a local normal reference range (21 volunteers) using a z-score. Blood levels of IL-1b, IL-6, IL-8, IL10, IL-12p40, MCP-1, TGFb, GRO, TNFa, IFNy, FGF2, PDGF were measured using ELISA, compared with 10 healthy controls.

Results

There were no significant differences in cytokine levels between CS and ARVC; most cytokine levels were higher in CS, except IL-6, IL-8 and MCP-1 in ARVC (Table 1). Increased PET uptake was noted in 1 segment of 1 ARVC patient, and in 1–2 segments of 5 CS patients (z-scores 2.25 SD; 2.15–2.38 SD). No pattern of uptake distinguished ARVC from CS, qualitatively assessing LV polar maps (Figure 1A, B). SUVmax and mean uptake were higher in CS vs. ARVC (p<0.05; p=0.13). No significant correlation between cytokine levels and PET uptake was detected (Figure 1C, D).

Conclusion

Quantitative PET/CT uptake and a blood inflammatory panel did not have utility in differentiating the two conditions in our population. There was generally more PET and serum inflammatory activity in CS.

Funding Acknowledgement

Type of funding source: Public hospital(s). Main funding source(s): NHS Endowments

A randomized controlled trial to determine the efficacy of a high carbohydrate and high protein ready-to-eat food product for weight loss

Incorporating meal replacements has been shown to produce a significantly greater weight loss than a conventional reduced calorie diet. Ready-to-eat conventional foods may also be effective in this role and provide additional benefit because of their palatability, acceptance and enjoyment and thus increase dietary compliance. This trial investigated the efficacy of a ready-to-eat food product (Vita-Weat biscuit) that is both high in carbohydrate and high in protein as part of a diet prescription for weight loss in an overweight and obese population group. A total of 76 participants were randomized to a 6-week weight loss intervention including the ready-to-eat food product (intervention group) or advice on the 'Australian Guide to Healthy Eating' (control group). Both groups lost approximately 2 kg weight which equated to a reduction in body mass index of 0.70 kg m(-2) . There was no significant difference in percentage weight loss from screening to 6 weeks between the two groups; mean difference for the intervention vs.

CONTROL GROUP

-0.20% (95% confidence interval: -0.96, 1.36); P = 0.73. Both diets were nutritionally matched and well-accepted over the 6-week period. This study shows that the inclusion of a ready-to-eat food product can be included as part of a dietary programme to achieve a clinically significant weight loss over a short period. This may have benefit when incorporated into an individual's meal plan intermittently to assist weight control. It also provides support for current public health nutritional guidelines as the participants in this study following such advice were also successful in achieving a clinically meaningful weight loss.

Piloting the CANRISK tool in Vancouver Coastal Health

INTRODUCTION

Vancouver Coastal Health Authority's Healthy Living Program implemented this pilot study to test and validate the Canadian Diabetes Risk Assessment Questionnaire (CANRISK) developed by the Public Health Agency of Canada as a screening tool for undiagnosed type 2 diabetes mellitus (DM) and prediabetes. Key objectives were to test the feasibility and acceptability of screening urban ethnic groups using the CANRISK, increase awareness of risk factors for DM and preDM and develop resources for lifestyle change.

METHODS

The study recruited participants through community groups and churches, intraorganizational emails, primary care clinics and word of mouth. They completed the CANRISK and an oral glucose tolerance test (OGTT) either individually or as part of a group. Groups received a brief diabetes prevention information session. Documents to support lifestyle change were distributed to all participants.

RESULTS

Participants (n = 556) were recruited among East Asian, Caucasian, South Asian and Latin American ethnic groups. Of these, 17% had OGTT results in the preDM range and 3% in the DM range. Over 90% of participants reported that the CANRISK wording was clear and that they had received useful information about lowering their diabetes risk.

CONCLUSION

The benefit of using an OGTT was in identifying 11% of the sample of participants who had impaired glucose tolerance (IGT) and did not show abnormal fasting plasma glucose (FPG) results. All participants with abnormal laboratory results were provided with follow-up educational interventions in their own language.

Species dependent differences in the actions of sympathetic nerves and noradrenaline in the internal anal sphincter

Excitatory motor innervation to the internal anal sphincter (IAS) of the monkey, the rabbit and mouse were compared. Contractile responses to electrical field stimulation of nerves (EFS, atropine 1 micromol L(-1) and N(omega)-nitro-L-arginine 100 micromol L(-1) present throughout) were examined in isolated strips of IAS. In the monkey IAS, EFS caused frequency dependent (1-30 Hz) contractions which were abolished by guanethidine (10 micromol L(-1)) or phentolamine (3 micromol L(-1)). The sympathetic neurotransmitter noradrenaline (NA) also caused concentration-dependent (10 nmol L(-1)-100 micromol L(-1)) contractions which were abolished by phentolamine revealing a small relaxation that was abolished by propranolol (3 micromol L(-1)). In contrast, EFS caused only relaxation of the mouse and rabbit IAS which was not affected by guanethidine. Furthermore, NA relaxed these muscles and relaxation was nearly abolished by combined addition of phentolamine and propranolol. In conclusion, the monkey IAS is functionally innervated by sympathetic nerves that contract the muscle via excitatory alpha-adrenergic receptors. In contrast, no significant motor function could be identified for sympathetic nerves in the rabbit or mouse IAS although adrenergic receptors linked to muscle inhibition are present. These data reveal species dependent differences in sympathetic motor innervation and suggest that some species are more appropriate than others as models for motor innervation to the human IAS.

Changes in Excitability of the Cortical Projections to the Human Tibialis Anterior After Paired Associative Stimulation

Paired associative stimulation (PAS) based on Hebb's law of association can induce plastic changes in the intact human. The optimal interstimulus interval (ISI) between the peripheral nerve and transcranial magnetic stimulus is not known for muscles of the lower leg. The aims of this study were to investigate the effect of PAS for a variety of ISIs and to explore the efficacy of PAS when applied during dynamic activation of the target muscle. PAS was applied at 0.2 Hz for 30 min with the tibialis anterior (TA) at rest. The ISI was varied randomly in seven sessions ( n = 5). Subsequently, PAS was applied ( n = 14, ISI = 55 ms) with the TA relaxed or dorsi-flexing. Finally, an optimized ISI based on the subject somatosensory evoked potential (SEP) latency plus a central processing delay (6 ms) was used ( n = 13). Motor-evoked potentials (MEPs) were elicited in the TA before and after the intervention, and the size of the TA MEP was extracted. ISIs of 45, 50, and 55 ms increased and 40 ms decreased TA MEP significantly ( P = 0.01). PAS during dorsi-flexion increased TA MEP size by 92% ( P = 0.001). PAS delivered at rest resulted in a nonsignificant increase; however, when the ISI was optimized from SEP latency recordings, all subjects showed significant increases ( P = 0.002). No changes in MEP size occurred in the antagonist. Results confirm that the excitability of the corticospinal projections to the TA but not the antagonist can be increased after PAS. This is strongly dependent on the individualized ISI and on the activation state of the muscle.

Interplay between inhibition of adenosine uptake and phosphodiesterase type 3 on cardiac function by cilostazol, an agent to treat intermittent claudication

The authors have recently shown that cilostazol, a type 3 cyclic nucleotide phosphodiesterase (PDE3) inhibitor, has a much weaker positive inotropic effect than milrinone, a PDE3 inhibitor of similar potency. They have also shown that cilostazol inhibits adenosine uptake, whereas milrinone has no such effect. This study investigated the possible cardiac functional significance of cilostazol on adenosine uptake inhibition. In isolated rabbit hearts, 10 microM of cilostazol elevated adenosine concentration in interstitial dialysate (0.16 +/- 0.01 microM, or approximately 0.81 microM in the interstitial space when adjusted for recovery rate of microdialysis) and coronary effluent (0.69 +/- 0.03 microM ). The values are significantly higher than those for 10 microM of milrinone (0.11 +/- 0.1 microM in interstitial dialysate and 0.2 +/- 0.04 microM in coronary effluent). Although cilostazol increased contractility, heart rate, and coronary flow in isolated rabbit hearts, the effect on contractility and heart rate was significantly augmented in the presence of an adenosine A 1 receptor antagonist. Conversely, an adenosine A 1 receptor agonist or an adenosine uptake inhibitor attenuated the positive inotropic effect of milrinone. These results indicate that adenosine uptake inhibition by cilostazol increases interstitial and circulatory adenosine concentration, and antagonizes PDE3 inhibition-induced contractility and heart rate increases through an adenosine A 1 receptor-mediated mechanism.

Fas activation reduces neutrophil adhesion to endothelial cells

Polymorphonuclear neutrophils (PMN) express apoptotic markers and lose effector functions including adhesion, chemotaxis, and phagocytosis when cultured overnight. Although the loss of function correlates with apoptosis, it is not clear if functions are lost before an early marker of apoptosis, the display of phosphatidylserine (PS), targets PMN for removal by phagocytic cells. To address this question, freshly isolated PMN were treated with Fas-activating antibodies to induce apoptosis rapidly. Early markers of apoptosis and PMA-stimulated adhesion to endothelial cells were measured. After 1 h of Fas exposure, only 16% PMN had externalized PS. In contrast, Fas activation reduced PMA-stimulated adhesion between 68 and 27% depending on PMA concentration. The loss of adhesion was accompanied by a reduction in beta2 integrin expression and receptor clustering. These results indicate that the Fas-induced loss of adhesion may precede PS externalization and could limit participation in the inflammatory response before PS externalization targets PMN for removal.

Inhibition of adenosine uptake and augmentation of ischemia-induced increase of interstitial adenosine by cilostazol, an agent to treat intermittent claudication

Cilostazol (Pletal), a quinolinone derivative with a cyclic nucleotide phosphodiesterase type 3 (PDE3) inhibitory activity, was recently approved by the Food and Drug Administration for treatment of symptoms of intermittent claudication (IC). However, the underlying mechanisms of action are not entirely clear. In this study, we showed that cilostazol inhibited adenosine uptake into cardiac ventricular myocytes, coronary artery smooth muscle, and endothelial cells with a median effective concentration (EC50) approximately 10 microM. In vivo, cilostazol increased cardiac interstitial adenosine levels after a 2-min ischemia in rabbit hearts (329 +/- 92% increase vs. 102 +/- 29% ischemia alone). The combination of cilostazol and 2-min ischemia reduced infarction from subsequent 30-min regional ischemia and 3 h of reperfusion (infarct size was 18 +/- 4% vs. 53 +/- 3% in the hearts with 2-min ischemia alone or 48 +/- 2% in the hearts treated with cilostazol alone). In contrast, milrinone had no effect on either adenosine uptake or interstitial adenosine levels. These data show that cilostazol, unlike milrinone, inhibits adenosine uptake, and thus potentiates adenosine accumulation from a 2-min ischemia. Future studies are needed to investigate the role of adenosine in the treatment of IC by cilostazol.

Clinical applications of the holmium:YAG laser in disorders of the paediatric airway

OBJECTIVE

The aim of this study was to review the role of the holmium:YAG laser in the management of paediatric airway disorders.

METHOD

Twenty-six paediatric patients underwent 42 airway procedures between June 1993 and August 1996 in a tertiary care centre. A case series design was used.

OUTCOME MEASURES

Safety, precision, hemostasis, bone-cutting properties, and accessibility of the lesion to the equipment were compared to standard therapies. Postoperative outcomes were then compared to standard therapies.

RESULTS

Eight patients underwent correction of choanal atresia or revision, 10 patients underwent functional endoscopic sinus surgery, 3 underwent excision of tracheal granuloma, 2 underwent excision of tracheal web or revisions, 1 underwent excision of subglottic stenosis and bronchial stenosis, 1 underwent excision hemangioma of the tongue, and 1 underwent excision papilloma of the oral cavity. One patient in 42 procedures suffered a surgical complication. Our early success rates are comparable to other series using the carbon dioxide laser or cold instruments.

CONCLUSION

The holmium:YAG laser is a safe, effective tool in the treatment of paediatric airway disorders and offers the advantage of a flexible fibre-optic system, good hemostasis, and better bone-cutting characteristics compared to the carbon dioxide laser, which is in widespread clinical use.

Comparison of the effects of cilostazol and milrinone on intracellular cAMP levels and cellular function in platelets and cardiac cells

Cilostazol is a potent cyclic nucleotide phosphodiesterase (PDE) type 3 (PDE3) inhibitor that was recently approved by the Food and Drug Administration (FDA) for the treatment of intermittent claudication. Its efficacy is presumed to be due to its vasodilatory and platelet activation inhibitory activities. Compared with those treated with placebo, patients treated with cilostazol showed a minimal increase in cardiac adverse events. Because of its PDE3 inhibitory activity, however, the possibility that cilostazol exerts positive cardiac inotropic effects is a safety concern. Therefore we compared the effects of cilostazol with those of milrinone, a selective PDE3 inhibitor, on intracellular cyclic adenosine monophosphate (cAMP) levels in platelets, cardiac ventricular myocytes, and coronary smooth muscle cells. We also compared the corresponding functional changes in these cells. Cilostazol and milrinone both caused a concentration-dependent increase in the cAMP level in rabbit and human platelets with similar potency. Furthermore, cilostazol and milrinone were equally effective in inhibiting human platelet aggregation with a median inhibitory concentration (IC50) of 0.9 and 2 microM, respectively. In rabbit ventricular myocytes, however, cilostazol elevated cAMP levels to a significantly lesser extent (p < 0.05 vs. milrinone). By using isolated rabbit hearts with a Langendorff preparation, we showed that milrinone is a very potent cardiotonic agent; it concentration-dependently increased left ventricular developed pressure (LVDP) and contractility. Cilostazol was less effective in increasing LVDP and contractility (p < 0.05 vs. milrinone), which is consistent with the cardiac cAMP levels. The cardiac effect of OPC-13015, a metabolite of cilostazol with about sevenfold higher PDE3 inhibition, was similar to cilostazol. Whereas milrinone concentration-dependently increased cAMP in rabbit coronary smooth muscle cells, cilostazol did not have such an effect. However, both compounds increased coronary flow equally in rabbit hearts. Our results show that although cilostazol and milrinone both inhibit PDE3, cilostazol preferentially acts on vascular elements (platelets and flow). This unique profile of cilostazol is consistent with its beneficial and safe clinical outcomes in patients with intermittent claudication.

Students' tactics of resistance and teachers' stress

In a study of 134 college teachers, teachers' self-reported stress scores were significantly and positively related with their perceptions of students' use of reluctant compliance and deception tactics in resistance to on-task learning.

Vesnarinone inhibits adenosine uptake in endothelial cells, smooth muscle cells and myocytes, and mediates cytoprotection

Vesnarinone is a novel synthetic inotropic agent. Recently, it has been reported that vesnarinone inhibits adenosine uptake in the B-lymphocytoid cell line. Since extracellular adenosine is cardioprotective, we examined whether vesnarinone inhibits adenosine uptake in cells constituting the cardiovascular system. 1 microCi of -3H-adenosine was added to cells of the myocyte cell line (C2C12), human coronary smooth muscle cell line (HCASMC), human and bovine coronary endothelial cell lines (HCAEC and BCAEC), bovine arterial endothelial cell line (BAEC), and human umbilical venous endothelial cell line (HUVEC). After 10 s-5 min, cells were separated from free [3H]adenosine, and the radioactivity was measured. When 0.1-100 microM of vesnarinone was added to each cell line, the uptake of adenosine was inhibited dose-dependently {% inhibition of -3H-adenosine uptake at 10 and 30 microM of vesnarinone: 14 and 33% (C2C12), 47 and 72% (HCASMC), 37 and 58% (HCAEC), 42 and 68% (BCAEC), 19 and 68% (BAEC), 29 and 59% (HUVEC)}. The cellular viability of HCAEC exposed to 60 min of hypoxia and 60 min of reoxygenation increased from 34+/-5 to 67+/-6% (Trypan blue exclusion test) and 23+/-5 to 78+/-6% (LDH release), which was completely blunted by 8-sulfophenyltheophylline, an adenosine receptor antagonist, and was partially blunted by alpha,beta-methyleneadenosine 5'-diphosphate, an inhibitor of ecto-5'-nucleotidase. We also found that vesnarinone is cytoprotective against hypoxia and reoxygenation in C2C12 and HCASMC. We conclude that vesnarinone inhibits the uptake of adenosine in cardiovascular cells, which contributes to cytoprotection.

Vesnarinone is a selective inhibitor of macrophage TNF(alpha) release

Vesnarinone is an experimental drug that has been used successfully in the treatment of congestive heart failure patients. In this report we investigate the effect of vesnarinone on the cytokine secretory products of mononuclear phagocytes. In a concentration-dependent manner, the drug inhibits the endotoxin(LPS)-stimulated release of tumor necrosis factor (TNF) alpha and suppresses interleukin(IL)-6 release, but does not affect the release of IL-1 alpha, IL-10 and leukemia inhibitory factor (LIF) by mouse peritoneal macrophages. Using competitive polymerase chain reaction (PCR) analyses, we find that vesnarinone significantly reduces TNF(alpha), but not IL-10 mRNA. In addition to LPS, the drug inhibits TNF(alpha) release induced by several other stimuli. The inhibitory effect of the drug on the TNF(alpha) biosynthesis can be observed in differentiated human monocytes, in macrophage cell lines, and in synovial adherent cells from rheumatoid arthritis patients. Although the precise mode of action of vesnarinone in the signal transduction pathway leading to the selective inhibition of TNF(alpha) is not known, the drug might be useful in the treatment of diseases involving that cytokine.

Increase of the expression of midecamycin 4"-hydroxyl propionyltransferase gene (mpt) by a promoter-like fragment from the midecamycin producing strain

The promoter region of the midecamycin 4"-hydroxyl propionyltransferase gene (mpt) gene was reconstructed by PCR, and ligated with a fragment from the midecamycin producing strain (Streptomyces mycarofaciens var. 68) which contained fairly strong promoter activity (PLF). Recombinant plasmids pCHFPE2 (promoter region of mpt was reconstructed by combining the PLF in the upstream of its own promoter) and pCHFPE3 (the promoter of mpt was replaced by PLF) were obtained. The extent of expression of mpt was measured according to the amount of propionylspiramycin bioconverted from exogenous spiramycin by transformants of S. lividans TK24 containing pCHFPE2 and pCHFPE3. The results showed that the PLF could increase the expression of mpt in S. lividans TK24 up to 89.02% and 58.53%, respectively, and also enhance the expression in the industrial spiramycin producing strain S. spiramyceticus to a great extent.

Cyclic nucleotide phosphodiesterase type IV participates in the regulation of IL-10 and in the subsequent inhibition of TNF-alpha and IL-6 release by endotoxin-stimulated macrophages

We have recently shown that PGE2 inhibits the release of TNF-alpha from LPS-stimulated murine peritoneal macrophages via a feedback mechanism involving IL-10. Here we demonstrate that a rolipram-sensitive phosphodiesterase (PDE) type IV participates in the regulation of IL-10 synthesis. Selective PDE IV inhibitors (rolipram and RO-20-1724), but not selective inhibitors of other types of PDE, significantly augment marcrophage IL-10 production and contribute to the inhibition of TNF-alpha and IL-6 release. The addition of rolipram to LPS-stimulated macrophages results in the accumulation of cAMP and in the significant augmentation of IL-10 release. Competitive PCR analysis reveals that the drug dramatically increases IL-10 mRNA, but does not affect TNF-alpha mRNA. The inhibitory effect of rolipram on TNF-alpha can be significantly but incompletely reversed by anti-IL-10 Ab, whereas the effect of the drug on IL-6 can be completely reversed by anti-IL-10. In endotoxemic mice, the administration of rolipram increases serum IL-10 and reduces TNF-alpha and IL-6 levels. Northern blot analysis of spleens from these mice shows that rolipram increases IL-10 mRNA, whereas TNF-alpha mRNA remains largely unchanged. These results suggest that a rolipram-sensitive PDE type IV is involved in the production of IL-10 and in turn contributes to the inhibition of TNF-alpha and IL-6 release.

Cyclic nucleotide phosphodiesterase type IV participates in the regulation of IL-10 and in the subsequent inhibition of TNF-alpha and IL-6 release by endotoxin-stimulated macrophages

We have recently shown that PGE2 inhibits the release of TNF-alpha from LPS-stimulated murine peritoneal macrophages via a feedback mechanism involving IL-10. Here we demonstrate that a rolipram-sensitive phosphodiesterase (PDE) type IV participates in the regulation of IL-10 synthesis. Selective PDE IV inhibitors (rolipram and RO-20-1724), but not selective inhibitors of other types of PDE, significantly augment marcrophage IL-10 production and contribute to the inhibition of TNF-alpha and IL-6 release. The addition of rolipram to LPS-stimulated macrophages results in the accumulation of cAMP and in the significant augmentation of IL-10 release. Competitive PCR analysis reveals that the drug dramatically increases IL-10 mRNA, but does not affect TNF-alpha mRNA. The inhibitory effect of rolipram on TNF-alpha can be significantly but incompletely reversed by anti-IL-10 Ab, whereas the effect of the drug on IL-6 can be completely reversed by anti-IL-10. In endotoxemic mice, the administration of rolipram increases serum IL-10 and reduces TNF-alpha and IL-6 levels. Northern blot analysis of spleens from these mice shows that rolipram increases IL-10 mRNA, whereas TNF-alpha mRNA remains largely unchanged. These results suggest that a rolipram-sensitive PDE type IV is involved in the production of IL-10 and in turn contributes to the inhibition of TNF-alpha and IL-6 release.