Relation of olfactory event-related potentials to changes in stimulus concentration

Objective: The aim of this study was to investigate the influence of odorant concentration on the olfactory event-related potential (OERP).Design and Methods: OERP were evaluated in 8 men and 8 women (17–34 years of age) in response to 4 concentrations of vanillin (7, 28, 56 and 84% v/v). Sixteen presentations of each concentration (stimulus duration 200 ms, interval 40 s, flow 8 l/min) were applied in a randomized order. EEG recordings were made at 3 midline sites (pos. Fz, Cz, Pz). Amplitudes and latencies of four peaks were measured (latencies in ms at Pz after stimulation with 84% v/v vanillin): P1 (277), N1 (348), P2 (412) and P3 (496). Statistical analysis was performed with MANOVAs (`concentration', `recording site'=within-subject-factors; `age' as covariate).Results: With increasing stimulus concentration amplitudes became significantly larger; this was most pronounced for P3 (P1N1: F=2.90, P<0.05; N1P2: F=5.15, P<0.01; N1P3: F=35.7, P<0.001; P3: F=38.6; P<0.001). Correspondingly, latencies shortened with increasing concentrations (P1: F=25.2; N1: 17.51; P2: 14.8; P3: 13.4; all P<0.001). While there was no correlation between OERP amplitudes and butanol odor detection thresholds, latencies were the shorter the lower the subjects' thresholds (coefficients of correlations for peak latencies at Cz for 84% v/v: P1 r₁₅=minus0.59; N1 r₁₅=minus0.58; P2 r₁₅=minus0.55; P3 r₁₅=minus0.45).Conclusions: The results indicated that both OERP amplitudes and latencies are related to the concentration of olfactory stimuli. They also suggested that latencies exhibit a stronger relation to changes in stimulus intensity compared to OERP amplitudes.     

Psychosocial Work Environment and Musculoskeletal Symptoms among 21-Year-Old Workers: A Population-Based Investigation (2011-2013)

Background

The current labour market is becoming more flexible and informal, with job insecurity selectively affecting young workers. However, the role of these increasing adverse psychosocial working conditions on health outcomes remains little known among newly employed workers.

Objective

To estimate the associations between psychosocial work environment and musculoskeletal outcomes (widespread pain syndrome features and regional pain) in a population-based sample of young workers.

Methods

Cross-sectional data from workers aged 21 years were collected during the third wave of the EPITeen cohort study (2011-2013; n=650). The Job Content Questionnaire was used to characterize the psychosocial work environment according to the demand-control-support model. Data on pain and non-pain dimensions of the widespread pain syndrome (Fibromyalgia Survey Questionnaire) as well as on regional musculoskeletal pain (Nordic Musculoskeletal Questionnaire) were also collected. Crude and adjusted odds ratios (OR) with 95% confidence intervals (95% CI) were computed using logistic regression and all estimates were adjusted for sex, education and occupational biomechanical demands.

Results

Job insecurity was significantly associated to the non-pain dimension of the widespread pain syndrome (adjusted OR [95% CI]=1.51 [1.08, 2.12]). Young workers with strain jobs were significantly more likely to report high levels of non-pain symptoms when compared with those with no-strain jobs and this effect was even stronger when social support was added to the main exposure: workers with strain jobs and low social support had twice the odds of reporting high levels of non-pain features than those with high strain but high social support jobs (adjusted OR=1.86, 95% CI: 1.04, 3.31). These significant associations were not observed when widespread pain or multisite regional pain were the outcomes.

Conclusion

In the beginning of professional life, high strain jobs were associated to non-pain complaints, especially when the work environment provided also low social support.     

Auditory event-related potentials to the apparent auditory image motion

Auditory event-related potentials (ERP) were registered to the dichotically presented white noise stimuli (duration 1500 ms, band 150-1200 Hz). Abrupt or gradual change ofinteraural time difference in the middle of stimuli (750 ms after sound offset) was perceived as an apparent auditory image (AI) instant relocation or motion from the midline to one of the ears. In responses these stimuli two ERPs were observed: one to the sound onset, and second--to the onset of motion or AI relocation. ERPs to AI relocation differed from those to sound onset in longer components latencies (123 ms versus 105 ms for N 1,227 ms versus 190 ms for P2). In responses to AI motion component latencies were even longer (N1: 137 ms, P2: 240 ms); N1 amplitude was greater at sites contralateral to the AI motion direction.     

Reaction of wild-type and Glu243Asp variant yeast cytochrome c oxidase with O2

We have studied internal electron transfer during the reaction of Saccharomyces cerevisiae mitochondrial cytochrome c oxidase with dioxygen. Similar absorbance changes were observed with this yeast oxidase as with the previously studied Rhodobacter sphaeroides and bovine mitochondrial oxidases, which suggests that the reaction proceeds along the same trajectory. However, notable differences were observed in rates and electron-transfer equilibrium constants of specific reaction steps, for example the ferryl (F) to oxidized (O) reaction was faster with the yeast (0.4 ms) than with the bovine oxidase (~ 1 ms) and a larger fraction Cu_A was oxidized with the yeast than with the bovine oxidase in the peroxy (P_R) to F reaction. Furthermore, upon replacement of Glu243, located at the end of the so-called D proton pathway, by Asp the P_R → F and F → O reactions were slowed by factors of ~ 3 and ~ 10, respectively, and electron transfer from Cu_A to heme a during the P_R → F reaction was not observed. These data indicate that during reduction of dioxygen protons are transferred through the D pathway, via Glu243, to the catalytic site in the yeast mitochondrial oxidase. This article is part of a Special Issue entitled: 18th European Bioenergetic Conference.     

New techniques in female pudendal somatosensory evoked potential testing

Objective—The primary nerves innervating the female genitalia are the dorsal nerve of the clitoris (DNC) and the perineal nerve, which innervate the clitoris and the external genitalia/distal vagina, respectively. We describe two novel electrodiagnostic techniques for evaluating the integrity of these female genital somatosensory pathways.

Subjects and methods—Seventy-seven healthy women (mean age 29.3 years) were enrolled for this study. We performed DNC somatosensory evoked potentials (SEPs), stimulating through self-adhesive disk electrodes on either side of the clitoris. Perineal nerve SEPs were evoked through a vaginal probe. Cortical responses were measured through cup electrodes affixed to the scalp at Cpz and Fpz. Stimulus parameters were duration 0.1?ms, frequency 4.1?Hz, filters 5–5,000?Hz, at three times sensory threshold.

Results—DNC and perineal nerve SEPs from both the right and left sides were reproducible and easily discerned. The mean P1 latencies were: right DNC 39.4?ms (SD 2.8?ms), left DNC 39.3?ms (SD 3.3?ms), right perineal nerve 37.8?ms (SD 3.4?ms), left perineal nerve 37.6?ms (SD 3.1?ms). We recorded SEP responses from 90 to 92% of subjects for the DNC, and 69% for the perineal nerve.

Conclusions—We are able to evoke somatosensory potentials from the four primary somatic nerves that mediate female genital cutaneous sensation. In healthy subjects, the DNC responses are robust and maintain laterality. The perineal nerve responses are less consistently obtained, but when recorded, are easily discerned. These preliminary data provide a foundation from which to study female genital innervation, particularly as it applies to sexual function.     

Directionality of auditory nerve fiber responses to pure tone stimuli in the grassfrog, Rana temporaria. II. Spike timing

We studied the directionality of spike timing in the responses of single auditory nerve fibers of the grass frog, Rana temporaria, to tone burst stimulation. Both the latency of the first spike after stimulus onset and the preferred firing phase during the stimulus were studied. In addition, the directionality of the phase of eardrum vibrations was measured. The response latency showed systematic and statistically significant changes with sound direction at both low and high frequencies. The latency changes were correlated with response strength (spike rate) changes and were probably the result of directional changes in effective stimulus intensity. Systematic changes in the preferred firing phase were seen in all fibers that showed phaselocking (i.e., at frequencies below 500–700 Hz). The mean phase lead for stimulation from the contralateral side was approximately 140° at 200 Hz and decreased to approximately 100° at 700 Hz. These phaseshifts correspond to differences in spike timing of approximately 2 ms and 0.4 ms respectively. The phaseshifts were nearly independent of stimulus intensity. The phase directionality of eardrum vibrations was smaller than that of the nerve fibers. Hence, the strong directional phaseshifts shown by the nerve fibers probably reflect the directional characteristics of extratympanic pathways. Accepted: 23 November 1996     

Electrochemical oxidation of ethanol using Nafion electrodes modified with heterobimetallic catalysts

Chemically modified electrodes were prepared by adsorption of Nafion/catalyst films of the type Nafion/Cp(PPh₃)Ru(μ-I)(μ-dppm)PdCl₂ (N1), Nafion/[η⁵-C₅H₄CH₂CH₂(NHMe₂)⁺]Ru(PPh₃)(μ-I)(μ-dppm)PtCl₂ (N2), Nafion/[η⁵-C₅H₄CH₂CH₂(NHMe₂)⁺]Ru(PPh₃)(μ-Cl)(μ-dppm)PdCl₂ (N3), Nafion/Cp(CO)Fe(μ-I)(μ-dppm)PdI₂ (N4) and Nafion/Cp(CO)Ru(μ-I)(μ-dppm)PtI₂ (N5) on glassy and vitreous carbon electrodes. Cyclic voltammetry and bulk electrolysis experiments were performed to assess the ability of these modified electrodes to electrocatalytically oxidize ethanol. Cyclic voltammograms using the N1-N5 modified glassy carbon electrodes displayed significant catalytic activity compared to oxidation of ethanol catalyzed by 1 in homogeneous solution. Bulk electrolysis of ethanol using electrodes coated with Nafion supported complexes 1-3 resulted in formation of the two- and four-electron oxidation products acetaldehyde and acetic acid, respectively, whilst bulk electrolysis using the complexes 4 and 5 produced only acetaldehyde.     

Differences in Achieving Hba1C Goals Among Patients Seen by Endocrinologists and Primary Care Providers

Objective: This study evaluated whether there is a difference in the proportion of patients with type 2 diabetes who achieve a hemoglobin A1c (HbA1c) <7% within one year following treatment by an endocrinologist or primary care physician (PCP).Methods: We conducted a retrospective, propensity-matched study of patients with type 2 diabetes that were not optimally controlled and seen within our health system from 2007–2016. We assessed differences in short term health outcomes for patients following an endocrinologist visit compared to a PCP visit.Results: Patients seen by endocrinologists obtained HbA1c control at a faster rate (hazard ratio = 1.226; 95% confidence interval = 1.01 to 1.488) than those seen by a PCP. Furthermore, 34.5% and 29.5% of those treated by endocrinologists and PCPs, respectively, obtained HbA1c control by one year. Endocrinologists were more likely to prescribe a new medication class within 90 days than PCPs (14.1% versus 10.3%, respectively, P = .043). There was no difference in the risk of hospitalization between groups; 24.4% and 24.1% of those treated by endocrinologists and PCPs, respectively, were hospitalized within one year.Conclusion: Patients treated by endocrinology specialists were more likely to achieve a target HbA1c of <7% (53 mmol/mol) than those treated by PCPs in our health-care system. The performance difference may be partially explained by a higher rate of adding new classes of diabetes medications to the patient's pharmacologic regimens within 90 days by endocrinologists compared with PCPs. The long-term impact of these differences is unknown but has the potential to have an unfavorable impact on the health of the population.Abbreviations: ACP = American College of Physicians; CI = confidence interval; DUHS = Duke University Health System; HbA1c = hemoglobin A1c; HR = hazard ratio; PCP = primary care physician; SMD = standard mean difference     

The N400 in a semantic categorization task across 6 decades

Objectives: To characterize the effects of normal aging on the amplitude, latency and scalp distribution of the N400 congruity effect.Methods: Event-related brain potentials (ERPs) were recorded from 72 adults (half of them men) between the ages of 20 and 80 years (12/decade) as they performed a semantic categorization task. Participants listened to spoken phrases (e.g. `a type of fruit' or `the opposite of black') followed about 1 s later by a visually-presented word that either did or did not fit with the sense of the preceding phrase; they reported the word read and whether or not it was appropriate. ERP measurements (mean amplitudes, peak amplitudes, peak latencies) were subjected to analysis of variance and linear regression analyses.Results: All participants, regardless of age, produced larger N400s to words that did not fit than to those that did. The N400 congruity effect (no-fit ERPs−fit ERPs) showed a reliable linear decrease in the amplitude (0.05–0.09 μV per year, r=0.40) and a reliable linear increase peak latency (1.5–2.1 ms/year, r=0.60) with age.Conclusions: In sum, the N400 semantic congruity effect at the scalp gets smaller, slower and more variable with age, consistent with a quantitative rather than qualitative change in semantic processing (integration) with normal aging.     

PGE2 and PGF2α release by human peritoneal macrophages in endometriosis

Objective: To test for differences in the amount and activity of peritoneal macrophages present in the peritoneal fluid of women with, and without endometriosis using prostaglandin release by macrophages in culture as a marker.Patients: Women of reproductive age undergoing laparoscopy for infertility or chronic pelvic pain with postoperative diagnosis of endometriosis and women undergoing laparoscopy for sterilization.Methods: Peritoneal fluid was aspirated during laparoscopy, volume was recorded, macrophages were isolated via a Ficoll Paque gradient and kept in primary culture. PGE₂ and PGF_2α release of the cells were measured before and after stimulation with zymosan.Results: Women with endometriosis had significantly more peritoneal macrophages than controls. Peritoneal macrophages of women with endometriosis released significantly more PGE₂ than those of the control group: 8.4 ± 2.0 versus 1.4 ± 0.4 ng/ml/10⁶cells (mean ± SEM, p=0.0005) and PGF_2α : 10 ± 4.3 (endometriosis) versus 1.8 ± 0.4 (control) ng/ml/10⁶cells (mean ± SEM, p = 0.045).Conclusion: There is a significant increase in the amount of prostaglandins released by peritoneal macrophages from women with endometriosis. These prostaglandins might alter uterine and tubal contractility, thereby affecting fertility.     

The development of the somatosensory evoked potential in the unanaesthetized fetal sheep

Somatosensory evoked potentials were recorded in utero from 13 chronically instrumented fetal lambs (97 to 148 days of gestation) following electrical stimulation of the upper lip or upper limb. Several clear and reproducible peaks were observed. Following upper lip stimulation, peaks were seen with mean peak latencies of 9, 13.2, 17.8, 21.3, 33.8 and 206 ms at a gestational age of 125 days. Similar peaks, but of slightly later mean latencies, were seen following limb stimulation. These peaks demonstrated significant gestational age related falls in peak latencies (P less than 0.05). Several of the mid to late latency peaks, notably those occurring at 21.3, 33.8 and 206 ms, demonstrated changes (P less than 0.05) in both latency (longer in low voltage) and amplitude (reduced in low voltage) dependent on electrocorticographic state. Rate of stimulus presentation also had a significant effect on both amplitude and latency of several peaks (P less than 0.05) with this effect lessening with advancing gestational age. Evoked potentials can thus be successfully obtained from chronically instrumented fetal lambs and provide a useful indice for studies of neural maturation.     

Synthesis and evaluation of conformationally constrained peptide analogues as the Src SH3 domain binding ligands

Src kinase activity is regulated by the interaction of SH3 domain with protein sequences that are rich in proline residues. Identification of more potent SH3 domain binding ligands that can regulate Src kinase activity is a subject of major interest. Conformationally constrained peptides have been previously used for improving the binding potency of the Src SH2 domain binding peptide ligands and peptide substrates of the substrate-binding site of Src. A series of peptide analogues of Ac-VSLARRPLPPLP (1, Ac-VSL12, K_d = 0.34 μM) were synthesized by introducing conformational constraints to improve the binding affinity towards the Src SH3 domain. Peptides synthesized through cyclization between N-terminal to C-terminal [VSLARRPLPPLP] or N-terminal to side chain flanking residues (i.e., [^βAVS]LARRPLPPLP and [VSLE]RRPLPPLP) exhibited at least 6.4-fold less binding affinity (K_d = 2.19–4.85 μM) when compared to 1. The data suggest upon N-terminal cyclization with C-terminal or flanking residues, the interactions of the amino acids in the core RPLPPLP reduce significantly with the residues within the Src SH3 domain. Conformationally constrained peptide V[SLARRPLPPLP] (5) was synthesized through cyclization of C-terminal to the serine side chain and displayed a comparable binding affinity (K_d = 0.35 μM) towards the Src SH3 domain versus that of 1. Thus, this template may be used to optimize and generate more potent analogues with higher stability.     

Effect of Gluten-FREE Diet on Metabolic Control and Anthropometric Parameters in Type 1 Diabetes with Subclinical Celiac Disease: A Randomized Controlled Trial

Objective: It is unclear whether the institution of gluten-free diet (GFD) is beneficial in patients with type 1 diabetes (T1DM) and subclinical celiac disease (CD). Our primary objective was to evaluate the effect of GFD on the frequency of hypoglycemia, in patients with T1DM and subclinical CD. Our secondary objective was to investigate the effect of GFD on height, weight, glycosylated hemoglobin (HbA1c), insulin dose requirement, and bone mineral homeostasis.Methods: We carried out a prospective open label randomized controlled trial (RCT). Patients with T1DM and subclinical CD were randomized to receive GFD or a normal diet for 1 year. The primary outcome was the frequency of hypoglycemic episodes (blood glucose <70 mg/dL) measured by self-monitoring of blood glucose (SMBG) at the sixth month of the study in the 2 groups.Results: Screening for CD was carried out in 320 T1DM patients. Thirty eligible patients were randomized to receive GFD (n = 15) or a normal diet (n = 15). The mean number of hypoglycemic episodes/month recorded by SMBG and the mean time spent in hypoglycemia measured by CGM (minutes) in the GFD group versus the non-GFD group at six months was 2.3 minutes versus 3.4 minutes (P = .5) and 124.1 minutes versus 356.9 minutes (P = .1), respectively. The mean number of hypoglycemic episodes/month significantly declined in the GFD group (3.5 episodes at baseline versus 2.3 episodes at the sixth month; P = .03). The mean HbA1c declined by 0.73% in the GFD group and rose by 0.99% in non-GFD group at study completion.Conclusion: This is the first RCT to assess the effect of GFD in T1DM and subclinical CD. A trend towards a decrease in hypoglycemic episodes and better glycemic control was seen in patients receiving GFD.Abbreviations: BMC = bone mineral content; BMI = body mass index; CD = celiac disease; CGM = continuous glucose monitoring; GFD = gluten-free diet; Hb = hemoglobin; HbA1c = glycosylated hemoglobin; iPTH = intact parathyroid hormone; RCT = randomized controlled trial; SMBG = self-monitoring of blood glucose; T1DM = type 1 diabetes mellitus; tTG-IgA = tissue transglutaminase immunoglobulin A     

Evidence for a new early acceptor in Photosystem I of plants. An ESR investigation of reaction center triplet yield and of the reduced intermediary acceptors

The yield of the triplet state of the primary electron donor of Photosystem I of photosynthesis (P^T-700) and the characteristic parameters (g value, line shape, saturation behavior) of the ESR signal of the photoaccumulated intermediary acceptor A have been measured for two types of Photosystem I subchloroplast particles: Triton particles (TSF 1, about 100 chlorophyll molecules per P-700) that contain the iron-sulfur acceptors F_X, F_B and F_A, and lithium dodecyl sulfate (LDS) particles (about 40 chlorophyll molecules per P-700) that lack these iron-sulfur acceptors. The results are: (i) In Triton particles the yield of P^T-700 upon illumination is independent of the redox state of A and of F_X,B,A and is maximally about 5% of the active reaction centers at 5 K. The molecular sublevel decay rates are k_x = 1100 s^?1 ± 10%, k_y = 1300 s^?1 ± 10% and k_z = 83 s^?1 ± 20%. In LDS particles the triplet yield decreases linearly with concentration of reduced intermediary acceptors, the maximal yield being about 4% at 5 K assuming full P-700 activity. (ii) In Triton particles the acceptor complex A consists of two acceptors A₀ and A₁, with A₀ preceding A₁. In LDS particles at temperatures below ?30°C only A₀ is photoactive. (iii) The spin-polarized ESR signal found in the time-resolved ESR experiments with Triton particles is attributed to a polarized P-700-A^?₁ spectrum. The decay kinetics are complex and are influenced by transient nutation effects, even at low microwave power. It is concluded that the lifetime at 5 K of P-700A₀A^?₁ must exceed 5 ms. We conclude that P^T-700 originates from charge recombination of P-700A^?₀, and that in Triton particles A₀ and A₁ are both photoaccumulated upon cooling at low redox potential in the light. Since the state P-700AF^?_X does not give rise to triplet formation the 5% triplet yield in Triton particles is probably due to centers with damaged electron transport.     

Effects of Liraglutide 3.0 Mg on Weight and Risk Factors in Hispanic Versus Non-Hipanic Populations: Subgroup Analysis from Scale Randomized Trials

Objective: Scarce data exist on pharmacotherapy for obesity in Hispanic individuals. This post hoc analysis of pooled data from 4 phase 3a trials compared the efficacy and safety of liraglutide 3.0 mg versus placebo, as adjunct to a reduced-calorie diet and physical activity, in Hispanic versus non-Hispanic subgroups.Methods: We conducted the double-blind randomized, placebo-controlled trials in adults with a minimum body mass index (BMI) of 27 kg/m² with at least 1 comorbidity, or a minimum BMI of 30 kg/m², at clinical research sites worldwide. In this analysis, we investigated possible differences in treatment effects between 534 Hispanics (10.4% of the population) and 4,597 non-Hispanics (89.6%) through statistical tests of interaction between subgroups and treatment. Variables examined included mean and categorical weight change, cardiovascular risk markers, and safety data.Results: Both subgroups achieved clinically significant mean weight loss at end-of-treatment with liraglutide 3.0 mg versus placebo: Hispanics 7.0% versus 1.5%, treatment difference -5.1% (95% CI, -6.2 to -4.0); non-Hispanics 7.5% versus 2.3%, -5.2% (95% CI, -5.5 to -4.8). More individuals in both subgroups lost ≥5%, >10%, and >15% of their baseline weight with liraglutide 3.0 mg than with placebo. Efficacy endpoints generally did not vary with ethnicity (P>.05). Adverse events were comparable between ethnic subgroups, with more gastrointestinal disorders reported with liraglutide 3.0 mg than placebo.Conclusion: Efficacy and safety were largely similar between Hispanic and non-Hispanic subgroups. Results support that liraglutide 3.0 mg, used with a reduced-calorie diet and physical activity, can facilitate weight loss in Hispanic individuals.Abbreviations:A1c = glycated hemoglobinBMI = body mass indexCI = confidence intervalFPG = fasting plasma glucoseGLP-1 = glucagon-like peptide-1hsCRP = high-sensitivity C-reactive proteinSCALE = Satiety and Clinical Adiposity – Liraglutide Evidence in individuals with and without diabetesT2DM = type 2 diabetes mellitus     

Treatment Intensification with Insulin Degludec/Insulin Aspart Twice Daily: Randomized Study to Compare Simple and Step-Wise Titration Algorithms

Objective: This 26-week, multicenter, randomized, open-label, parallel-group, treat-to-target trial in adults with type 2 diabetes compared the efficacy and safety of treatment intensification algorithms with twice-daily (BID) insulin degludec/insulin aspart (IDegAsp).Methods: Patients randomized 1:1 to IDegAsp BID used either a ‘Simple’ algorithm (twice-weekly dose adjustments based on a single prebreakfast and pre-evening meal self-monitored plasma glucose [SMPG] measurement; IDegAsp[BID_Simple], n = 136) or a ‘Stepwise’ algorithm (once-weekly dose adjustments based on the lowest of 3 pre-breakfast and 3 pre-evening meal SMPG values; IDegAsp[BID_Step-wise], n = 136).Results: After 26 weeks, mean change from baseline in glycated hemoglobin (HbA1c) with IDegAsp[BID_Simple] was noninferior to IDegAsp[BID_Step-wise] (-15 mmol/mol versus -14 mmol/mol; 95% confidence interval [CI] upper limit, <4 mmol/mol) (baseline HbA1c: 66.3 mmol/mol IDegAsp[BID_Simple] and 66.6 mmol/mol IDegAsp[BID_Step-wise]). The proportion of patients who achieved HbA1c <7.0% (<53 mmol/mol) at the end of the trial was 66.9% with IDegAsp[BID_Simple] and 62.5% with IDegAsp[BID_Step-wise]. Fasting plasma glucose levels were reduced with each titration algorithm (-1.51 mmol/L IDegAsp[BID_Simple] versus -1.95 mmol/L IDegAsp[BID_Step-wise]). Weight gain was 3.8 kg IDegAsp[BID_Simple] versus 2.6 kg IDegAsp[BID_Step-wise], and rates of overall confirmed hypoglycemia (5.16 episodes per patient-year of exposure [PYE] versus 8.93 PYE) and nocturnal confirmed hypoglycemia (0.78 PYE versus 1.33 PYE) were significantly lower with IDegAsp[BID_Step-wise] versus IDegAsp[BID_Simple]. There were no significant differences in insulin dose increments between groups.Conclusion: Treatment intensification with IDegAsp[BID_Simple] was noninferior to IDegAsp[BID_Step-wise]. Both titration algorithms were well tolerated; however, the more conservative step-wise algorithm led to less weight gain and fewer hypoglycemic episodes. Clinicaltrials.gov: NCT01680341Abbreviations:AEs = adverse eventsANOVA = analysis of varianceBID = twice-dailyBID_Simple = ‘Simple’ algorithm twice-weekly dose adjustments based on a single pre-breakfast and pre–evening meal self-monitored plasma glucose measurementBID_Step-wise = ‘Step-wise’ algorithm once-weekly dose adjustments based on the lowest of 3 prebreakfast and 3 pre–evening meal self-monitored plasma glucose valuesCI = confidence intervalETD = estimated mean treatment differenceFPG = fasting plasma glucoseHbA1c = glycated hemoglobinIAsp = insulin aspartIDeg = insulin degludecIDegAsp = insulin degludec/insulin aspartIGlar = insulin glargineOAD = oral antidiabetic drugPYE = patient-year of exposureSMPG = self-monitored plasma glucoseSU = sulfonylureaT2D = type 2 diabetes     

Recognition intensities of submolecular structures,mammalian glyco-structural units,ligand cluster and polyvalency in abrin-a-carbohydrate interactions

Abrin-a is the most toxic fraction of lectins isolated from Abrus precatorius seeds and belongs to the family of type 2 ribosome inactivating proteins (RIP). This toxin may act as a defense molecule in plants against viruses, fungi and insects, where attachment of abrin-a to the exposed glycans on the surface of target cells is the crucial and initial step of its cytotoxicity. Although it has been studied for over four decades, the recognition factors involved in abrin-a-carbohydrate interaction remains to be clarified. In this study, roles of mammalian glyco-structural units, ligand clusters and polyvalency in abrin-a recognition were comprehensively analyzed by enzyme-linked lectinosorbent binding and inhibition assays. The results indicate that: (i) this toxin prefers oligosaccharides having α-anomer of galactose (Gal) at the non-reducing terminal than the corresponding β-anomer; (ii) Galα1-3Galα1- (B_α), Galα1-4Gal (E), Galβ1-3GalNAc (T) and Galβ1-3/4GlcNAc (I/II) related oligosaccharides were the active glyco-structural units; (iii) tri-antennary II_β, prepared from N-glycan of asialo fetuin, played a dominant role in recognition; (iv) many high-density polyvalent I_β/II_β and E_β glycotopes enhanced the reactivity; (v) the carbohydrate recognition domain of abrin-a is proposed to be a combination of a small cavity type of Gal as major site and a groove type of additional one to tetrasaccharides as subsites with a preference of α1-3/4/6Gal, β1-3GalNAc, β1-3/4/6GlcNAc, β1-4/6Glc, β1-3DAra and β1-4Man as subterminal sugars; (vi) size of the carbohydrate recognition domain may be as large enough to accommodate a linear pentasaccharide and complementary to Galα1-3Galβ1-4GlcNAc β1-3Galβ1-4Glc (gailipenta) sequence. A comparison of the recognition factors and combining sites of abrin-a with ricin, another highly toxic lectin, was also performed to further understand the differences in recognition factors between these two type 2 RIPs.     

Cycloartane glycosides from Astragalus aureus

Eight cycloartane-type triterpene glycosides (1-8) were isolated from Astragalus aureus Willd along with ten known cycloartane-type glycosides (9-18). Their structures were established by the extensive use of 1D and 2D-NMR experiments along with ESIMS and HRMS analyses. Compounds 1-5 are cyclocanthogenin glycosides, whereas compounds 6-8 are based on cyclocephalogenin as aglycon, more unusual in the plant kingdom, so far reported only from Astragalus spp. Moreover, for the first time monoglycosides of cyclocanthogenin (5) and cyclocephalogenin (7, 8) are reported. All of the compounds tested for their cytotoxic activities against a number of cancer cell lines. Among the compounds, only 8 exhibited activity versus human breast cancer (MCF7) at 45 μM concentration.     

Reexamination of Electrical Stimulation on Sarcoplasmic Reticulum Fragments In Vitro

The effect of direct electrical stimulation on suspensions of sarcoplasmic reticulum membrane fragments (SRF) was carefully re-examined using the method of Lee et al. (1966) J. Gen. Physiol. 49:689. Inhibition of Ca⁺⁺ uptake or release by electrical stimulation was observed. When platinum electrodes were used as stimulating electrodes, the effect was dependent on the total current passed through the suspension. On the contrary, when silver-silver chloride electrodes were used, no effect was observed even if voltage and current were the same as in the case of the platinum electrodes. In addition, apparent re-uptake of Ca⁺⁺ after cessation of electrical stimulation using platinum electrodes was shown to be due to a binding of Ca⁺⁺ to denatured SRF which did not require an energy supply such as ATP, although such re-uptake had been taken as strong evidence of electrical response of SRF in Lee's paper. Finally, it was concluded that the effect of electrical stimulation on SRF was attributable to the irreversible denaturation of SRF due to the oxidation caused by the chlorine generated at the platinum electrode.