Xylella fastidiosa Does Not Occur in Lebanon

Xylella fastidiosa has been reported as responsible for a devastating disease on olive trees in Apulia region (south‐eastern Italy), characterized by a quick decline syndrome. In Lebanon, the pathogen was recently associated with leaf scorch symptoms on oleander, and reports on leaf scorch and dieback of olive trees branches by technicians and farmers have shown an increasing trend in the main agricultural areas. To assess the occurrence and distribution of the pathogen in Lebanon, samples of twigs from olive trees (82), olive seedlings (26), grapevine (30), oleander (32) and ornamentals imported from Italy (48) were analysed by isolation on four agarized media, serological techniques (ELISA and DTBIA) using Xylella fastidiosa‐specific antibodies and by PCR, using three specific sets of primers. Results unequivocally demonstrated that all the collected samples were free from the pathogen. As well, both detection protocols and attempts at isolating the pathogen on agarized media demonstrated that oleander samples gathered from American University campus in Beirut, where X. fastidiosa was previously reported, were not infected. Nevertheless, continuous monitoring and rigorous control measures of propagative materials are necessary to prevent the introduction of Xylella fastidiosa in Lebanon.     

Conditions under which Arousal Does and Does Not Elevate Height Estimates

We present a series of experiments that explore the boundary conditions for how emotional arousal influences height estimates. Four experiments are presented, which investigated the influence of context, situation-relevance, intensity, and attribution of arousal on height estimates. In Experiment 1, we manipulated the environmental context to signal either danger (viewing a height from above) or safety (viewing a height from below). High arousal only increased height estimates made from above. In Experiment 2, two arousal inductions were used that contained either 1) height-relevant arousing images or 2) height-irrelevant arousing images. Regardless of theme, arousal increased height estimates compared to a neutral group. In Experiment 3, arousal intensity was manipulated by inserting an intermediate or long delay between the induction and height estimates. A brief, but not a long, delay from the arousal induction served to increase height estimates. In Experiment 4, an attribution manipulation was included, and those participants who were made aware of the source of their arousal reduced their height estimates compared to participants who received no attribution instructions. Thus, arousal that is attributed to its true source is discounted from feelings elicited by the height, thereby reducing height estimates. Overall, we suggest that misattributed, embodied arousal is used as a cue when estimating heights from above that can lead to overestimation.     

Ghrelin Does Not Influence Gastric Emptying in Obese Subjects

Objective: To evaluate the relationship between fasting plasma concentrations of ghrelin and gastric emptying in obese individuals compared with lean subjects. Research Methods and Procedures: We included 20 obese patients (9 men and 11 women, BMI > 30 kg/m²) and 16 nonobese control subjects (7 men and 9 women, BMI ≤ 25 kg/m²). Gastric emptying of solids (egg sandwich labeled with radionuclide) was measured at 120 minutes with (99m)Tc‐single photon emission computed tomography imaging. Ghrelin and leptin were analyzed by radioimmunoassay and ELISA methods, respectively. Results: The gastric half‐emptying time was similar in obese men and women (67.8 ± 14.79 vs. 66.6 ± 13.56 minutes) but significantly shorter (p < 0.001) than in the control population (men: 88.09 ± 11.72 minutes; women: 97.25 ± 10.31 minutes). Ghrelin levels were significantly lower in obese subjects (131.37 ± 47.67 vs. 306.3 ± 45.52 pg/mL; p < 0.0001 in men and 162.13 ± 32.95 vs. 272.8 ± 47.77 pg/mL; p < 0.0001 in women). A negative correlation between gastric emptying and fasting ghrelin levels was observed only in lean subjects (y = ?0.2391x + 157.9; R² = 0.95). Also, in the lean group, ghrelin was the only significant independent determinant of gastric emptying, explaining 98% of the variance (adjusted R²) in a multiple regression analysis. Discussion: This report shows that, in humans, gastric emptying is faster in obese subjects than in lean controls and that, whereas ghrelin is the best determinant of gastric kinetics in healthy controls, this action is lost in obesity.     

Proteasome Inhibitor Does Not Enhance MPTP Neurotoxicity in Mice

Dysfunction of the proteasome function is known to be a potential mechanism for dopaminergic neuron degeneration. Here, we investigated to determine whether systematic administration of proteasome inhibitor, carbobenzoxy-l-γ-t-butyl-l-glutamyl-l-alanyl-l-leucinal (PSI), causes the increased susceptibility in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated mice. PSI was injected into MPTP-treated mice over a period of 2 weeks. Thereafter, we evaluated the effect of PSI 2, 4, and 8 weeks after the cessation of treatment with PSI. In the present study with HPLC analysis, PSI did not enhance MPTP-induced dopaminergic neurotoxicity in mice. Our present study with Western blot analysis also demonstrated that the reduction of tyrosine hydroxylase (TH) and glial fibrillary acidic protein (GFAP) protein levels in MPTP-treated mice was more pronounced than that in MPTP + PSI-treated animals. These results suggest that proteasome inhibitor did not enhance MPTP neurotoxicity in mice. Our findings suggest that proteasome inhibition is not a reliable model for PD. Thus, our findings provide further valuable information for the pathogenesis of Parkinson’s disease. Naoto Kadoguchi and Masahiro Umeda contributed equally to this work.     

Specialization Does Not Predict Individual Efficiency in an Ant

The ecological success of social insects is often attributed to an increase in efficiency achieved through division of labor between workers in a colony. Much research has therefore focused on the mechanism by which a division of labor is implemented, i.e., on how tasks are allocated to workers. However, the important assumption that specialists are indeed more efficient at their work than generalist individuals—the “Jack-of-all-trades is master of none” hypothesis—has rarely been tested. Here, I quantify worker efficiency, measured as work completed per time, in four different tasks in the ant Temnothorax albipennis: honey and protein foraging, collection of nest-building material, and brood transports in a colony emigration. I show that individual efficiency is not predicted by how specialized workers were on the respective task. Worker efficiency is also not consistently predicted by that worker''s overall activity or delay to begin the task. Even when only the worker''s rank relative to nestmates in the same colony was used, specialization did not predict efficiency in three out of the four tasks, and more specialized workers actually performed worse than others in the fourth task (collection of sand grains). I also show that the above relationships, as well as median individual efficiency, do not change with colony size. My results demonstrate that in an ant species without morphologically differentiated worker castes, workers may nevertheless differ in their ability to perform different tasks. Surprisingly, this variation is not utilized by the colony—worker allocation to tasks is unrelated to their ability to perform them. What, then, are the adaptive benefits of behavioral specialization, and why do workers choose tasks without regard for whether they can perform them well? We are still far from an understanding of the adaptive benefits of division of labor in social insects.     

Regenerating Sciatic Nerve Does Not Utilize Circulating Cholesterol

The rapid accumulation of myelin in the peripheral nervous system during the early postnatal period requires large amounts of cholesterol, a major myelin lipid. All of the cholesterol accumulating in the developing rat sciatic nerve is synthesized locally within the nerve, rather than being derived from the supply in lipoproteins in the systemic circulation (Jurevics and Morell, J. Lipid Res. 5:112–120; 1994). Since this lack of utilization of circulating cholesterol may relate to exclusion by the blood-nerve barrier, we examined the sources of cholesterol needed for regeneration following nerve injury, when the blood-nerve barrier is breached. One sciatic nerve was crushed or transected, and at various times later, the rate of cholesterol accumulation was compared with the rate of local in vivo synthesis of cholesterol within the nerve, utilizing intraperitoneally injected ³H₂O as precursor. The accumulation of additional cholesterol in nerve during regeneration and remyelination could all be accounted for by that locally synthesized within the nerve. There was also an increase in cholesterol esters in injured nerve segments; in crushed nerves, these levels decreased during regeneration and remyelination, consistent with reutilization of cholesterol originally salvaged by phagocytic macrophages and Schwann cells. Thus, regeneration and remyelination following injury in sciatic nerve utilizes both salvaged cholesterol and cholesterol synthesized locally within the nerve, but not cholesterol from the circulation.     

Menstrual Cycle Phase Does Not Predict Political Conservatism

Recent authors have reported a relationship between women''s fertility status, as indexed by menstrual cycle phase, and conservatism in moral, social and political values. We conducted a survey to test for the existence of a relationship between menstrual cycle day and conservatism.2213 women reporting regular menstrual cycles provided data about their political views. Of these women, 2208 provided information about their cycle date, 1260 provided additional evidence of reliability in self-reported cycle date, and of these, 750 also indicated an absence of hormonal disruptors such as recent hormonal contraception use, breastfeeding or pregnancy. Cycle day was used to estimate day-specific fertility rate (probability of conception); political conservatism was measured via direct self-report and via responses to the "Moral Foundations” questionnaire. We also recorded relationship status, which has been reported to interact with menstrual cycle phase in determining political preferences.We found no evidence of a relationship between estimated cyclical fertility changes and conservatism, and no evidence of an interaction between relationship status and cyclical fertility in determining political attitudes. Our findings were robust to multiple inclusion/exclusion criteria and to different methods of estimating fertility and measuring conservatism. In summary, the relationship between cycle-linked reproductive parameters and conservatism may be weaker or less reliable than previously thought.     

Relaxin Does Not Improve Angiotensin II-Induced Target-Organ Damage

Relaxin is a corpus-luteum produced protein hormone with vasodilatatory, anti-fibrotic, and angiogenic properties that are opposite to angiotensin (Ang) II. We investigated whether or not relaxin ameliorates Ang II-induced target-organ damage. We used double transgenic rats harboring both human renin and angiotensinogen genes (dTGR) that develop severe hypertension, target-organ damage, and die untreated within 7–8 weeks. Recombinant relaxin at a low (26 μg/kg/d) and a high dose (240 μg/kg/d) was given to 4 week-old dTGR and age-matched Sprague-Dawley rats (SD). Systolic blood pressure increased progressively in untreated dTGRs from 162±3 mmHg at week 5 to 225±5 mmHg at week 7. Relaxin had no effect on blood pressure whereas SD rats were normotensive (106±1 mmHg). Untreated and relaxin-treated dTGR had similarly severe cardiac hypertrophy indices. Relaxin did not ameliorate albuminuria and did not prevent matrix-protein deposition in the heart and kidney in dTGR. Finally, relaxin treatment did not reduce mortality. These data suggest that pharmacological doses of relaxin do not reverse severe effects of Ang II.     

Human Insulin Does Not Increase Bladder Cancer Risk

Background

Whether human insulin can induce bladder cancer is rarely studied.

Methods

The reimbursement databases of all Taiwanese diabetic patients from 1996 to 2009 were retrieved from the National Health Insurance. An entry date was set at 1 January 2004 and a total of 785,234 patients with type 2 diabetes were followed up for bladder cancer incidence until the end of 2009. Users of pioglitazone were excluded and the period since the initiation of insulin glargine (marketed after the entry date in Taiwan) was not included in the calculation of follow-up. Incidences for ever-users, never-users and subgroups of human insulin exposure (using tertile cutoffs of time since starting insulin, duration of therapy and cumulative dose) were calculated and the hazard ratios were estimated by Cox regression.

Results

There were 87,940 ever-users and 697,294 never-users, with respective numbers of incident bladder cancer of 454 (0.52%) and 3,330 (0.48%), and respective incidence of 120.49 and 94.74 per 100,000 person-years. The overall hazard ratios (95% confidence intervals) indicated a significant association with insulin in the age-sex-adjusted models [1.238 (1.122–1.366)], but not in the model adjusted for all covariates [1.063 (0.951–1.187)]. There was also a significant trend for the hazard ratios for the different categories of the dose-response parameters in the age-sex-adjusted models, which became insignificant when all covariates were adjusted.

Conclusions

This study relieves the concern of a bladder cancer risk associated with human insulin. Appropriate adjustment for confounders is important in the evaluation of cancer risk associated with a medication.     

Forceps Size Does Not Determine Fighting Success in European Earwigs

Male European earwigs (Forficula auricularia) possess substantially larger forceps than females and use these forceps to batter rivals in intrasexual contests to determine dominance. Although previous investigations have shown that male fighting and mating success increases with forceps size, it is not clear that sexual selection acts directly on forceps size per se; increased forceps size may be a correlated response to selection for some other trait. We experimentally reduced forceps length of males and paired them with unmanipulated males in staged encounters. Although apparent (postmanipulation) forceps length did not affect contest outcomes, original (premanipulation) forceps length did: males with longer original forceps won more contests. These results suggest that weapon size itself does not determine success in contests between male European earwigs. Thus, sexual selection may operate on forceps size in some other context or may act on some other trait that covaries with forceps size.     

Neuromedin U Does Not Act as a Decretin in Rats

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Fission Yeast Does Not Age under Favorable Conditions,but Does So after Stress

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