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The results of 61 alcohol treatment studies published from 1989 to 1993 are used to review the effectiveness of existing methodologies. Some of the studies, which used pre-treatment characteristics, conventional methodologies and experimental techniques, have come up with favorable results. However, results of some of the studies, particularly those which involved data from numerous sources, showed deviations from some conventional methodologies.

Abstract: The influence of temperature and relative humidity (RH) on the activity of three biocontrol agents—the yeast Metschnikowia pulcherrima LS16 and two strains of the yeast-like fungus Aureobasidium pullulans LS30 and AU34-2—against infection by A. carbonarius and ochratoxin A (OTA) accumulation in wine grape berries was investigated in lab-scale experiments. The presence of wounds on grape skin dramatically favored infection of berries by A. carbonarius strain A1102, since unwounded berries showed very low levels of infection at all conditions of RH and temperature tested. Artificially wounded berries pre-treated with the biocontrol agents were inoculated with the ochratoxigenic A. carbonarius strain A1102 and were incubated for 5days at two levels of RH (60% and 100%) and three different temperatures (20, 25 and 30°C). The three biocontrol agents were able to prevent infections at 60% RH and 20°C. At 60% RH and 25°C only strain AU34-2 achieved some protection on day 5, whereas at 30°C a limited biocontrol efficacy was evident only up to day 2. At 100% RH, LS16, LS30 and AU34-2 showed effective protection of grape berries at 20°C until the 5th day of incubation. The three biocontrol agents achieved significant protection at higher temperatures only until the 2nd day after the beginning of the experiment: all three strains at 25°C, and only strain LS16 at 30°C. After 5days, the three biocontrol agents were able to significantly reduce the level of OTA in berries at all the conditions tested. This occurred even when protection from infection was not significant, except at 30°C and 100% of RH for all the three strains, and at 25°C and 100% of RH for strain LS16. The biocontrol agents displayed a higher rate of colonization on grape berries at 20 and 25°C than at 30°C. The higher value of RH (100%) appeared to increase the rate of colonization, in particular at 20 and 25°C. Taken together, our results emphasize the significant influence of environmental factors on the effectiveness of biocontrol against A. carbonarius as well as on OTA contamination in wine grape berries, and the need for biocontrol agents that can cope with the environmental conditions that are conducive to attack by A. carbonarius. [Copyright &y& Elsevier]

Abstract: In a 2-year assessment carried out on tomato crops of Central and Southern Italy, a high incidence of Rhizoctonia solani and Sclerotium rolfsii was found. These fungal pathogens attack horticultural crops and are responsible for severe crown and stem rot. Because of technical, economical and environmental issues their chemical control is an arduous task. To find alternative and eco-compatible control methods, the effectiveness of two new antagonistic bacterial isolates (Burkholderia cepacia, T1A-2B, and Pseudomonas sp., T4B-2A), previously selected from suppressive organic amendments, were tested on tomato plants grown under both growth chamber and field conditions. The potential antagonists were compared with two commercial biofungicides, based on Bacillus subtilis (BSF4) and Trichoderma asperellum (TV1), and four synthetic fungicides (tolclofos-methyl, azoxystrobin, fosetyl-Al and fosetyl-Al + propamocarb). In 2-year field experiments carried out on tomato plants, the biocontrol bacteria as well as the other treatments were applied to the soil, proximal to the plant crowns and main roots, by means of an effective and specific system of drip irrigation. In all the experiments the novel selected biocontrol bacteria significantly reduced both incidence and severity of the diseases caused by S. rolfsii or R. solani, with results demonstrating effectiveness equal to TV1, better than BSF4 and comparable with the synthetic fungicides, except for tolclofos-methyl which was the most effective treatment. In field experiments, carried out for two consecutive years, isolate T1A-2B reduced up to 58.33% and up to 63.8% the severity of the diseases caused by S. rolfsii and R. solani respectively; whereas isolate T4B-2A gave reduction of S. rolfsii and R. solani diseases severity up to 73.2% and up to 62.7%, respectively. This investigation provided insight for the development of novel antagonistic bacterial isolates and, particularly, a suitable method for a more efficient antagonist''s distribution in the field in order to better control fungal crown and root rot of horticultural crops. [Copyright &y& Elsevier]

Abstract: Nicotinic acetylcholine receptors (nAChRs) are inhibited by several drugs that are commonly thought to be specific for L-type calcium channels (LTCCs). In neurons, LTCCs are activated by nicotine-induced depolarization to engage downstream signaling events; however, the role of LTCC drug interactions with nAChRs in signaling has not been examined in detail. We investigated the effects of LTCC ligands on nAChR currents and downstream signaling in rat superior cervical ganglion (SCG) neurons. We found that 10μM nicotine and 40mM K+ both reversibly depolarize SCG neurons to −20mV, sufficient to activate LTCCs and downstream signaling, including induction of nuclear phospho-CREB (pCREB); this induction was blocked by LTCC antagonists. Interestingly, the effects of LTCC antagonists on nicotine-induced signaling to CREB are not mediated by their actions on LTCCs, but rather via inhibition of nAChRs, which prevents nicotine-induced depolarization. We show that this effect is sufficient to block pCREB induction in neurons expressing an antagonist-insensitive LTCC. Taken together, our data show that, at concentrations typically used to block LTCCs, these antagonists inhibit nAChR currents and downstream signaling. These findings serve as a caution in attributing a role for LTCCs when using these drugs experimentally or therapeutically. [Copyright &y& Elsevier]

Abstract: A family of image contrast agent conjugates designed to undergo enzymatic activation has been synthesized. The agents underwent activation both with enzymatically active prostate specific antigen (PSA) and α-chymotrypsin, releasing free fluorophore via cleavage of a three-component system. A hexapeptide derivative showed exclusive activation by PSA and constitutes a method for tracking PSA activity in vitro. [Copyright &y& Elsevier]

Abstract: A family of differentially substituted poly(ethyleneglycol) building blocks has been assembled from commercially available material. Their utility is demonstrated by formation of amino acid conjugates, image contrast agents, gold nanoparticles, and functional antibody conjugates. Application in the cellular trafficking of antitumoral agent conjugates is expected. [Copyright &y& Elsevier]

Forty-nine compounds currently used as additives in foods were tested in combination with three biocontrol agents, the yeasts Rhodotorula glutinis, Cryptococcus laurentii, and the yeastlike fungus Aureobasidium pullulans, to increase their antagonistic activity against Penicillium expansum, the causal agent of blue mold on apples. Twelve additives dramatically improved the antagonistic activity of one or more of the tested biocontrol agents. In a two-way factorial experiment with these selected additives the percentage of P. expansum rots on apples was significantly influenced by the antagonist and the additive as well as by their interaction. The combination of the biocontrol agents and some additives resulted in a significantly higher activity with respect to the single treatments applied separately, producing additive or synergistic effects. Some of the selected additives combined with a low yeast concentration (106 cells per ml) had comparable or higher efficacy than the biocontrol agents applied alone at a 100-fold higher concentration (108 cells per ml). Some organic and inorganic calcium salts, natural gums, and some antioxidants displayed the best results. In general, the effect of each additive was specific to the biocontrol isolate used in the experiments. Possible mechanisms involved in the activity of these beneficial additives and their potential application in effective formulations of postharvest biofungicides are discussed. [ABSTRACT FROM AUTHOR]

Familial hemiplegic migraine type 1 (FHM1) arises from missense mutations in the gene encoding α1A, the pore-forming subunit of P/Q-type calcium channels. The nature of the channel disorder is fundamental to the disease, yet is not well understood. We studied how the most prevalent FHM1 mutation, a threonine to methionine substitution at position 666 (TM), affects both ionic current and gating current associated with channel activation, a previously unexplored feature of P/Q channels. Whole-cell currents were measured in HEK293 cells expressing channels containing either wild-type (WT) or TM α1A. Calcium currents were significantly smaller in cells expressing TM channels, consistent with previous reports. In contrast, surface expression of TM channels, measured by immunostaining against an extracellular epitope, was not decreased, and Western blots demonstrated that TM α1A subunits were expressed as full-length proteins. WT and TM gating currents were isolated by replacing Ca2+ with the nonpermeant cation La3+. The gating currents generated by the mutant channels were one-third that of WT, a deficiency sufficient to account for the observed attenuation in calcium current; the remaining gating current was no different in kinetics or voltage dependence. Thus, the decreased calcium influx seen with TM channels can be attributed to a reduced number of channels available to undergo the voltage-dependent conformational changes needed for channel opening, not to fewer channel proteins expressed on the cell surface. This identification of an intrinsic defect in FHM1 mutant channels helps explain their impact on neurotransmission when they occupy type-specific slots for P/Q channels at central nerve terminals. [ABSTRACT FROM AUTHOR]

Molecular fingerprinting of biocontrol agents is pivotal both for environmental monitoring and registration purposes. Fluorescent amplified fragment length polymorphism (fAFLP) analysis was utilised for the first time to investigate the intraspecific variability of the yeast-like fungus Aureobasidium pullulans, in order to identify specific molecular markers for its strain LS30, an effective biocontrol agent against major postharvest pathogens on different crops, and to pave the way to the development of molecular-based tools for unequivocal tracking of this agent after its release in the environment. Forty-eight isolates of A. pullulans from phyllosphere and carposphere of several crops from different sites of Southern Italy and Greece were analyzed by using four couples of primers. A pairwise comparison of fAFLP patterns was performed, for each primer pair, by using Dice similarity coefficient (SD). Four matrices were generated and, subsequently, averaged and combined for constructing a single dendrogram, in which clustering of fingerprints was performed with the unweighted pair groups (UPGMA). In the combined dendrogram, most of the isolates grouped into three main fAFLP clusters with levels of similarity ranging from 0.18 to 0.35. Only two isolates (AU73 and AU91) were very similar in all fAFLP patterns. Only primers AC/CA yielded three DNA sized fragments that appeared to be specific for LS30. [Copyright &y& Elsevier]

A mild and efficient method for preparation of GlcNAc derivatives by reaction of glycosyl acceptors with glycosyl oxazolines has been developed. The key feature is use of Yb(OTf)3 as promoter, requiring moderate reaction times and equivalence stoichiometry. We anticipate application in the preparation of a wide range of derivatives of this biologically important class of building blocks. [Copyright &y& Elsevier]

Twenty two analogues of SB-203207 have been prepared by total synthesis, and evaluated as inhibitors of a range of tRNA synthetases. Changes to the bicyclic core, removing either the terminal amino substituent or the sulfonyl group from the side chain, and altering either the carbon skeleton or stereochemistry of the isoleucine residue, decreases the potency of inhibition of isoleucyl tRNA synthetase. Substituting the isoleucine residue with other amino acids produces inhibitors of the corresponding synthetases. In particular, a methionine derivative is 50–100 times more potent against methionyl tRNA synthetase than against any of the corresponding isoleucyl, leucyl, valyl, alanyl and prolyl synthetases. [Copyright &y& Elsevier]

An abstract of the article "Voltage-Gated Calcium Channels, Calcium Signaling, and Channelopathies," by Yu-Qing Cao and colleagues is presented.

There is a rapidly growing body of research on the more negative aspects of the expanding millennial population. Alternatively, the current study explores possible benefits resulting from millennial traits typically considered to be negative, specifically entitlement and narcissism. The authors hypothesize that self-efficacy generated by the creation of service opportunities, may not only improve engagement, but may also lessen the influence of negative millennial traits including entitlement and narcissism. Hypotheses were explored using a sample of 239 millennials. Following Preacher and Hayes’ (2008) method for mediation, we found that the model tested was fully mediated. Results and discussion follow. [ABSTRACT FROM AUTHOR]

One strategy for isolating neuronal L-type calcium (Ca2+) currents, which typically comprise a minority of the whole cell current in neurons, has been to use pharmacological agents that increase channel activity. This study examines the effects of the benzoyl pyrrole FPL 64176 (FPL) on L-type Ca2+ currents and compares them to those of the dihydropyridine (+)-202-791. At micromolar concentrations, both agonists increased whole cell current amplitude in PC12 cells. However, FPL also significantly slowed the rate of activation and elicited a longer-lasting slow component of the tail current compared to (+)-202-791. In single channel cell-attached patch recordings, FPL increased open probability, first latency, mean closed time and mean open time more than (+)-202-791, with no difference in unitary conductance. These gating differences suggest that, compared to (+)-202-791, FPL decreases transition rates between open and closed conformations. Where examined, the actions of FPL and (+)-202-791 on whole cell L-type currents in sympathetic neurons appeared similar to those in PC12 cells. In contrast to its effects on L-type current, 10 μM FPL inhibited the majority of the whole cell current in HEK cells expressing a recombinant N-type Ca2+ channel, raising caution concerning the use of FPL as a selective L-type Ca2+ channel agonist in neurons. [Copyright &y& Elsevier]

Abstract: In excitable cells, membrane depolarization and activation of voltage-gated Ca2+ (CaV) channels trigger numerous cellular responses, including muscle contraction, secretion, and gene expression. Yet, while the mechanisms underlying excitation–contraction and excitation–secretion coupling have been extensively characterized, how neuronal activity is coupled to gene expression has remained more elusive. In this article, we will discuss recent progress toward understanding the relationship between patterns of channel activity driven by membrane depolarization and activation of the nuclear transcription factor CREB. We show that signaling strength is steeply dependent on membrane depolarization and is more sensitive to the open probability of CaV channels than the Ca2+ entry itself. Furthermore, our data indicate that by decoding CaV channel activity, CaMKII (a Ca2+/calmodulin-dependent protein kinase) links membrane excitation to activation of CREB in the nucleus. Together, these results revealed some interesting and unexpected similarities between excitation–transcription coupling and other forms of excitation–response coupling. [Copyright &y& Elsevier]

A family of image contrast agent conjugates designed to undergo enzymatic activation has been synthesized. The agents underwent activation both with enzymatically active prostate specific antigen and α-chymotrypsin, releasing free fluorophore via cleavage of a three-component system. [Copyright &y& Elsevier]