Synthesis and Structural Characterization of Novel Camphor-derived Amines

Two novel 4‐substituted camphidine derivatives 10a , b have been prepared from (+)‐camphor ( 1 ) in five steps, the Beckmann rearrangement being the bottleneck of the synthesis. Isoborneol derivative 5b , formed as a side product during the hydrogenation of arylidene ketone 3b , under Beckmann rearrangement conditions yielded interesting novel rearrangement products 11 and 12 . (1S)‐(+)‐Camphorquinone ( 13 ) was transformed into diamines 15 and 16 in two steps, the former being cyclized into an imidazoline salt 17 , an N‐heterocyclic carbene precursor. The structures of all novel compounds have been meticulously characterized using NMR techniques and/or single crystal X‐ray analysis. Chirality 24:778–788, 2012. © 2012 Wiley Periodicals, Inc.     

Plasmid content and bacteriocin production by five strains of Lactococcus lactis isolated from semi-hard homemade cheese

In this study, the plasmid content and bacteriocin production of natural isolates of lactococci were investigated. Five bacteriocin producing lactococcal strains (Lactococcus lactis subsp. lactis BGMN1-2, BGMN1-3, BGMN1-5, BGMN1-6, and BGMN2-7) were isolated as nonstarter microflora of semi-hard homemade cheese and characterized. All isolates contained a number of plasmids. It was shown that lcnB structural genes for bacteriocin lactococcin B were located on large plasmids in all isolates. In the strains BGMN1-3 and BGMN1-5 proteinase prtP genes collocated with lcnB. Furthermore, these strains produced two additional bacteriocins (LsbA and LsbB) with genes responsible for their production and immunity located on the small rolling circle-replicating plasmid pMN5. Using deletion experiments of pMN5, minimal replicon of the plasmid and involvement of a bacteriocin locus in plasmid maintenance were identified. In addition, plasmid curing experiments showed that genes for catabolism or transport of 10 carbohydrates in the strain BGMN1-5 were plasmid located.     

Epidemiology of HIV infection and AIDS in Croatia--an overview

This article presents an overview of HIV/AIDS epidemiology and surveillance in Croatia 20 years after the first documented case of AIDS in the country. Here we describe strategies employed for HIV/AIDS surveillance in Croatia as well as preliminary results of HIV seroprevalence among most-at-risk populations (MARPs) research conducted by the Infectious Diseases Epidemiology Service at the Croatian National Institute of Public Health (CNIPH). Croatia has a low incidence and prevalence of HIV and AIDS. At the end of 2005, there were 553 documented cases of HIV infection, 239 of which progressed to AIDS. In Croatia, AIDS is being registered within MARPs only and dominantly among men who have sex with men (MSM). AIDS patients and HIV infected persons are found in all parts of the country. Crude prevalence of HIV among MARPs was found to be 0.9%. It is necessary to continue with current prevention and control measures in the country, and to create a culture of awareness and precaution, a strategy that has proven effective in reducing risk of HIV infection.     

Early Activation of FGF and Nodal Pathways Mediates Cardiac Specification Independently of Wnt/β-Catenin Signaling

Background

Cardiac induction, the first step in heart development in vertebrate embryos, is thought to be initiated by anterior endoderm during gastrulation, but what the signals are and how they act is unknown. Several signaling pathways, including FGF, Nodal, BMP and Wnt have been implicated in cardiac specification, in both gain- and loss-of-function experiments. However, as these pathways regulate germ layer formation and patterning, their specific roles in cardiac induction have been difficult to define.

Methodology/Principal Findings

To investigate the mechanisms of cardiac induction directly we devised an assay based on conjugates of anterior endoderm from early gastrula stage Xenopus embryos as the inducing tissue and pluripotent ectodermal explants as the responding tissue. We show that the anterior endoderm produces a specific signal, as skeletal muscle is not induced. Cardiac inducing signal needs up to two hours of interaction with the responding tissue to produce an effect. While we found that the BMP pathway was not necessary, our results demonstrate that the FGF and Nodal pathways are essential for cardiogenesis. They were required only during the first hour of cardiogenesis, while sustained activation of ERK was required for at least four hours. Our results also show that transient early activation of the Wnt/β-catenin pathway has no effect on cardiogenesis, while later activation of the pathway antagonizes cardiac differentiation.

Conclusions/Significance

We have described an assay for investigating the mechanisms of cardiac induction by anterior endoderm. The assay was used to provide evidence for a direct, early and transient requirement of FGF and Nodal pathways. In addition, we demonstrate that Wnt/β-catenin pathway plays no direct role in vertebrate cardiac specification, but needs to be suppressed just prior to differentiation.     

The role of air quality in perception of health of the local population

The research aim was to investigate and establish the perception of health among population groups with different number of industrial polluters in their living environment. Namely, the Kostrena living area (3250 inhabitants) is situated near big industrial pollutant producers: INA oil refinery Urinj, thermo power plant Rijeka, shipyard "Viktor Lenac", while in Crikvenica living area such pollutant producers do not exist. In this research 146 subjects from Kostrena participated (74 men and 72 women with age average 40.8, SD 9.2 years), and 157 subjects from Crikvenica area (79 men and 78 women with age average 39.4, SD 10.1 years). The perception of health was measured by the means of SF-36 questionnaire variables. Lung function (FEV1, FVC, FEV25/75, PEF), cardiovascular function (systolic and diastolic arterial blood pressure, heart rate were also measured, including body proportion measures by the means of waste and hip circumference and silhouette test, in order to establish the eventual objective physical health parameter difference among examined population groups. Subjects from Kostrena perceived their general health, mental health, and vitality worse than subjects from Crikvenica. Group from Kostrena felt themself more limited in their roles due to emotional problems, perceiving more pain than group from Crikvenica. On the opposite site, social functioning of subjects from Kostrena was better in comparison to Crikvenica group. No signifficant differences between groups were found in physical functioning and in role limitation due to physical problems. In addition, there were no significant differences between groups in objective physical health parameters, such as pulmonary function, arterial blood pressure, pulse, and waist to hip ratio. Subjects using sensoric systems and the mental cognition about harmful environmental factors, perceive their health worse if there are present industrial resources in their environment, even when concentration of the pollutants are within legal ranges.     

4-Aryl-4-oxo-N-phenyl-2-aminylbutyramides as acetyl- and butyrylcholinesterase inhibitors. Preparation,anticholinesterase activity,docking study,and 3D structure–activity relationship based on molecular interaction fields

Synthesis and anticholinesterase activity of 4-aryl-4-oxo-N-phenyl-2-aminylbutyramides, novel class of reversible, moderately potent cholinesterase inhibitors, are reported. Simple substituent variation on aroyl moiety changes anti-AChE activity for two orders of magnitude; also substitution and type of hetero(ali)cycle in position 2 of butanoic moiety govern AChE/BChE selectivity. The most potent compounds showed mixed-type inhibition, indicating their binding to free enzyme and enzyme–substrate complex. Alignment-independent 3D QSAR study on reported compounds, and compounds having similar potencies obtained from the literature, confirmed that alkyl substitution on aroyl moiety of molecules is requisite for inhibition activity. The presence of hydrophobic moiety at close distance from hydrogen bond acceptor has favorable influence on inhibition potency. Docking studies show that compounds probably bind in the middle of the AChE active site gorge, but are buried deeper inside BChE active site gorge, as a consequence of larger BChE gorge void.     

Resolving taxonomic uncertainties using molecular systematics: <Emphasis Type="Italic">Salmo dentex</Emphasis> and the Balkan trout community

The genetic structure of Salmo dentex and its phylogenetic relations to sympatric salmonids in the Neretva and Skadar River basins were evaluated using mitochondrial DNA (mtDNA) control region, eight microsatellites, and somatolactin (SL) gene. In the Neretva River basin of Bosnia–Herzegovina, the results based on mtDNA analysis showed extensive haplotype sharing between S. marmoratus, S. dentex, and S. trutta, and were therefore not conclusive; however, F-statistics and assignment testing based on nuclear DNA markers indicated that S. dentex of the Neretva basin were grouped in a genetically unified cluster with S. marmoratus in the Neretva basin. Using the same analytical approach, S. dentex from the Skadar basin in Montenegro appeared to be genetically distinct from S. marmoratus in the same basin and indistinct from local S. trutta. Molecular data also indicated that S. dentex of the Neretva basin in Bosnia–Herzegovina are not closely related to S. dentex of the Skadar basin in Montenegro. Based on these results, we hypothesize S. dentex to be a particular life history form of S. marmoratus in the Neretva basin and of S. trutta in the Skadar basin. These results clearly demonstrate that S. dentex does not represent a monophyletic lineage and should not be considered a distinct species.     

Response of Growth Dynamics of Two Spring Geophytes to Light Regime in a Lime-Beech Forest

Blomaee accumulation, leaf longevity and growth rate of two spring forest geophytes, Scllla blfolla L. and Arum maculatum L. were estimated separately for three size groups within each population of these species. Despite the differences in leaf longevity, both species showed a similar pattern of blomass accumulation In relation to their phenologles and reproductive demands. Eco-physlological acclimation to changing light environment was assumed through photosynthetic parameters and dynamics of leaf area Index In the predominant size group of each species. A light response curve was measured under natural light for each species through the continuum of Its phenology to quantify the photosynthetic photon flux density at light saturation, light-saturated photosynthetic rate, light compensation point, and dark respiration. Light-saturated assimilation per leaf area basis, dark respiration rate and light compensation points were significantly higher in S. blfolla relative to A. maculatum. However, the acclimation of photosynthesis that would respond to light changes in environment was not found in S. bifolla. In contrast, In A. maculatum a marked shift In the light dependence of photosynthesis through the season was noticed, which resulted In a strong photosynthetic acclimation to the low-light conditions. Accompanied by significant leaf area Index, this efficient low-light photosynthesis enabled greater leaf longevity, and consequently longer accumulative period to A. maculatum. From the different parameters that we determined （both photosynthetic acclimation and growth strategy） it would appear that these species belong to two distinct subgroups： S. blfolla to the early and A. maculatum to the late vernals.