Can alien plants support generalist insect herbivores?

Simple rearing experiments were conducted to address two questions relevant to understanding how generalist lepidopteran herbivores interact with alien plants. Yellow-striped armyworm (Spodoptera ornithogalli), luna moth (Actias luna), bagworm (Thyridopteryx ephemeraeformis) and white-marked tussock moth (Orgyia leucostigma) were reared from egg to 5th instar on excised foliage in the laboratory to determine the degree to which highly polyphagous lepidopteran herbivores are physiologically capable of surviving and developing on the suite of alien plants naturalized in the mid-Atlantic. Actias luna larvae from a single population were similarly reared on a representative of each of the 25 native plant genera recorded as hosts for this species to compare the diet breadth of a local population with that listed over the entire geographic range of the species. With few exceptions, all four generalists either quickly starved or grew at an unsustainably low rate on alien foliage. Actias luna larvae survived for 18 days on only 44% of the native plants recorded as hosts over the entire range of this insect and thrived on only 7%. The data suggest that (1) alien plants are unlikely to produce as much generalist insect biomass as the native plants they replace and (2) Lepidoptera that qualify as generalists when host breadth is considered over their entire geographic range may express a far more specialized diet within local populations. Both of these conclusions support the hypothesis that alien plant invasions may seriously disrupt terrestrial food webs by reducing the insect biomass required by insectivores in higher trophic levels.     

Addition of hydrophilic and lipophilic compounds of biological relevance to the monoolein/water system. I. Phase behavior

The solubilization of hydrophilic and lipophilic molecules, with biological relevance, in the monoolein/water (MO/W) system has been investigated for phase behavior. Small angle X-ray scattering (SAXS), nuclear magnetic resonance (NMR) and optical microscopy (OM) have been used to characterize the microstructure of the liquid crystalline phases. Partial phase diagrams of the MO/W system in the presence of sodium decanoate, 1-adamantanamine hydrochloride, decanoic and dodecanoic acids, acetyl salicilic acid and retinol have been determined. The stability of the various phases has been followed for at least eight months. The polarity and the molecular structure of the additive determine whether it is located at the polar interface or in the apolar region of the lipid layer. Therefore, the additive affects the interfacial curvature of the lipid layer differently, which in turn will trigger transition to disparate phases. A cubic-to-reverse hexagonal phase transition has been observed with time for most of the ternary systems, with the exception of 1-adamantanamine hydrochloride and retinol. The release of free glycerol and oleic acid due to MO hydrolysis has been clearly demonstrated by 13C NMR. This would account for the changes in phase behavior observed with time. The released oleic acid, located in the MO acyl chain region, favors the inverse interfacial curvature. The average lipid dimensions in the cubic and in the reverse hexagonal phases have been calculated from SAXS data.     

Evidence of two populations of GABA(A) receptors in cerebellar granule cells in culture: different desensitization kinetics, pharmacology, serine/threonine kinase sensitivity, and localization

GABA(A) receptors of rat cerebellar granule cells in culture have been studied by the whole cell patch clamp technique. The biphasic desensitization kinetic observed could be due either to different desensitization mechanisms of a single receptor population or to different receptor populations. The overall data indicate that the latter hypothesis is most probably the correct one. In fact, the fast desensitizing component was selectively potentiated by a benzodiazepine agonist and preferentially down-regulated by activation of the protein serine/threonine kinases A and G, as a consequence of the latter characteristic that receptor population was preferentially down-regulated by previous activation of N-methyl-d-aspartate glutamate receptors, via production of nitric oxide and PKG activation, most probably in dendrites. The other population is benzodiazepine insensitive and not influenced by activation of PKA or PKG. This slowly desensitizing population may correspond to the extrasynaptic delta subunit containing GABA(A) receptors described by other authors. Instead, the rapidly desensitizing population appears to represent dendritic synaptic GABA(A) receptors.     

HHV 8 seroprevalence and transmission within Albanian family groups

The recently discovered Human Herpesvirus 8 (HHV 8) is associated with all clinical forms of Kaposi's sarcoma. While early research suggested that the virus was transmitted sexually and that it was present only in KS patients, more recent studies seem to show that infection with the virus is more common than once thought, presenting differing distribution patterns in different geographical areas. In this study we analyze seroprevalence and transmission of HHV 8 in a sample of 86 family groups from Albania. Participants were selected among families requesting routine pre-expatriation medical examinations at the Poliambulatorio Padre "L. Monti" in Tirana. Specimens were collected from 180 healthy individuals and tested for the presence of a specific antibody. Antibody anti-HHV-8 detection was performed by immunofluorescence assay (IFA) and enzyme-linked immunosorbent assay (ELISA). The study found an overall rate of HHV 8 seroprevalence of 20.0%. In 4.5% of couples the male and female were both positive, in 30.2% at least one partner was positive; (in 17.4% only the male was positive; in 12.8% only the female). These results support the hypothesis that HHV 8 spreads via multiple transmission routes.     

Pridopidine,a dopamine stabilizer,improves motor performance and shows neuroprotective effects in Huntington disease R6/2 mouse model

Huntington disease (HD) is a neurodegenerative disorder for which new treatments are urgently needed. Pridopidine is a new dopaminergic stabilizer, recently developed for the treatment of motor symptoms associated with HD. The therapeutic effect of pridopidine in patients with HD has been determined in two double‐blind randomized clinical trials, however, whether pridopidine exerts neuroprotection remains to be addressed. The main goal of this study was to define the potential neuroprotective effect of pridopidine, in HD in vivo and in vitro models, thus providing evidence that might support a potential disease‐modifying action of the drug and possibly clarifying other aspects of pridopidine mode‐of‐action. Our data corroborated the hypothesis of neuroprotective action of pridopidine in HD experimental models. Administration of pridopidine protected cells from apoptosis, and resulted in highly improved motor performance in R6/2 mice. The anti‐apoptotic effect observed in the in vitro system highlighted neuroprotective properties of the drug, and advanced the idea of sigma‐1‐receptor as an additional molecular target implicated in the mechanism of action of pridopidine. Coherent with protective effects, pridopidine‐mediated beneficial effects in R6/2 mice were associated with an increased expression of pro‐survival and neurostimulatory molecules, such as brain derived neurotrophic factor and DARPP32, and with a reduction in the size of mHtt aggregates in striatal tissues. Taken together, these findings support the theory of pridopidine as molecule with disease‐modifying properties in HD and advance the idea of a valuable therapeutic strategy for effectively treating the disease.     

Antibiotic Treatment of Severe Exacerbations of Chronic Obstructive Pulmonary Disease with Procalcitonin: A Randomized Noninferiority Trial

Background

The duration of antibiotic treatment of exacerbations of COPD (ECOPD) is controversial. Serum procalcitonin (PCT) is a biomarker of bacterial infection used to identify the cause of ECOPD.

Methods and Findings

We investigated whether a PCT-guided plan would allow a shorter duration of antibiotic treatment in patients with severe ECOPD. For this multicenter, randomized, non-inferiority trial, we enrolled 184 patients hospitalized with ECOPD from 18 hospitals in Italy. Patients were assigned to receive antibiotics for 10 days (standard group) or for either 3 or 10 days (PCT group). The primary outcome was the rate of ECOPD at 6 months. Having planned to recruit 400 patients, we randomized only 183: 93 in the PCT group and 90 in the standard group. Thus, the completed study was underpowered. The ECOPD rate at 6 months between PCT-guided and standard antibiotic treatment was not significant (% difference, 4.04; 90% confidence interval [CI], −7.23 to 15.31), but the CI included the non-inferiority margin of 15. In the PCT-guided group, about 50% of patients were treated for 3 days, and there was no difference in primary or secondary outcomes compared to patients treated for 10 days.

Conclusions

Although the primary and secondary clinical outcomes were no different for patients treated for 3 or 10 days in the PCT group, the conclusion that antibiotics can be safely stopped after 3 days in patients with low serum PCT cannot be substantiated statistically. Thus, the results of this study are inconclusive regarding the noninferiority of the PCT-guided plan compared to the standard antibiotic treatment. The study was funded by Agenzia Italiana del Farmaco (AIFA-FARM58J2XH). Clinical trial registered with www.clinicaltrials.gov (NCT01125098).

Trial Registration

ClinicalTrials.gov NCT01125098     

Expression of EIF3-p48/INT6, TID1 and Patched in cancer,a profiling of multiple tumor types and correlation of expression

Summary Alterations in eIF3-p48/INT6 gene expression have been implicated in murine and human mammary carcinogenesis. We examined levels of INT6 protein in human tumors and determined that breast and colon tumors clustered into distinct groups based on levels of INT6 expression and clinicopathological variables. We performed multiplex tissue immunoblotting of breast, colon, lung, and ovarian tumor tissues and found that INT6 protein levels positively correlated with those of TID1, Patched, p53, c-Jun, and phosphorylated-c-Jun proteins in a tissue-specific manner. INT6 and TID1 showed significant positive correlation in all tissue types tested. These findings were confirmed by immunohistochemical staining of INT6 and TID1. Further evidence supporting a cooperative role for INT6 and TID1 is the presence of endogenous INT6 and TID1 proteins as complexes. We detected co-immunoprecipitation between INT6 and TID1, as well as between INT6 and Patched. These findings suggest potential integrated roles for INT6, TID1, and Patched proteins in cell growth, development, and tumorigenesis. Additionally, these data suggest that the combination of INT6, TID1, and Patched protein levels may be useful biomarkers for the development of diagnostic assays. June L. Traico and Joon-Yong Chung contributed equally to this work.     

Cuticular Membrane Fine Structure of Nicotiana tabacum L. Leaves

The cuticular membrane (CM) ofNicotiana tabacumL., includingthe cellin wall (CW), was examined to gain more informationabout the nature and chemical constitution of its fine structurefor possible inclusion in a model system, as recent literaturequestions its function as a major water permeability barrier.Different preparation techniques were used and the results evaluatedto select a method for future studies on tobacco leaf cuticles.Fixation with OsO₄included in the primary fixative, either asa vapour or in combination with other agents, followed by OsO₄aspost-fixative, gave good contrast of the CM. The lamellar structureof the tobacco cuticle proper (CP) was revealed by contrastingwith uranyl acetate and lead citrate. The fine lamellar structureof the CP was very clearly contrasted when KMnO₄was includedin the primary fixative. This was interpreted as indicatingthe tobacco CP to be polar. The reticulate fibrillar patternof the tobacco cuticular layer (CL) containing polysaccharideswas well contrasted when either OsO₄or paraformaldehyde wereincluded in the primary fixative. Cold fixation with glutaraldehydeand dimethyl sulphoxide and post-fixation with OsO₄revealedelectron-opaque material in the outer cutinized, irregularlyoutlined, region of the CW. These ultrahistochemical reactionsare discussed in relation to the known chemical compositionand possible water permeability of the CM. Cuticular fine structure; cuticular transpiration; Nicotiana tabacumL.     

Rapid and simple determination of inulin in biological fluids by high-performance liquid chromatography with light-scattering detection

We report a new high-performance liquid chromatography method developed for measuring inulin in plasma and urine using ion moderated partition chromatography and evaporative light-scattering detection. Samples are deproteinized with a zinc acetate and phosphotungstic acid solution and added with melezitose as an internal standard. The chromatographic separation is carried out in 16 min at a flow-rate of 0.6 ml/min using deionized water as the mobile phase. Within-run precision, measured at four different concentrations (0.050 mg/ml, 0.150 mg/ml, 0.300 mg/ml and 1.200 mg/ml), ranges from 1.7 to 3.4% in plasma and from 1.5 to 3.5% in urine. Similarly, between-run precision is in plasma from 2.0 to 4.3% and in urine from 2.0 to 4.4%. Analytical recovery ranges from 97.9 to 100.1% in plasma and from 99.1 to 99.7% in urine, respectively. Detection limit (signal-to-noise ratio=3) is 5 μg/ml both in plasma and urine. The method is simple, sensitive, without interference due to hexoses or drugs commonly taken by patients with renal diseases, and offers the advantage of measuring inulin without previous hydrolysis of the molecule.