Aspects of the progesterone response in Hortaea werneckii: Steroid detoxification, protein induction and remodelling of the cell wall

Progesterone in sublethal concentrations temporarily inhibits growth of Hortaea werneckii. This study investigates some of the compensatory mechanisms which are activated in the presence of progesterone and are most probably contributing to escape from growth inhibition. These mechanisms lead on the one hand to progesterone biotransformation/detoxification but, on the other, are suggested to increase the resistance of H. werneckii to the steroid. Biotransformation can detoxify progesterone efficiently in the early logarithmic phase, with mostly inducible steroid transforming enzymes, while progesterone biotransformation/detoxification in the late logarithmic and stationary phases of growth is not very efficient. The relative contribution of constitutive steroid transforming enzymes to progesterone biotransformation is increased in these latter phases of growth. In the presence of progesterone, activation of the cell wall integrity pathway is suggested by the overexpression of Pck2 which was detected in the stationary as well as the logarithmic phase of growth of the yeast. Progesterone treated H. werneckii cells were found to be more resistant to cell lysis than mock treated cells, indicating for the first time changes in the yeast cell wall as a result of treatment with progesterone.     

Risk Assessment for Dermal Exposure of Organochlorine Pesticides for Local Fishermen in the Rangsit Agricultural Area,Central Thailand

Organochlorine pesticides (OCPs) used in agriculture and for public health purposes were banned in Thailand over the past decade; however, their persistent residues have been found in several agricultural areas of the country. This may result in adverse effects to human populations. This study investigated the concentration of organochlorine pesticides residues (OCPRs) in surface water and evaluated the potential cancer risk associated with dermal contact of the local fisherman fishing in the Khlong 7 canal, Rangsit agricultural area, central Thailand. Water samples were extracted using liquid-liquid extraction (LLE) and then analyzed by gas chromatography with microelectron capture detector (μ -ECD). The results show that low concentrations of OCPRs were detected in parts per billion (ppb or ng/ml) levels, that is, ∑ Endosulfan (α -, β -, and -sulfate) 0.082 ng/ml > DDT and derivatives 0.019 ng/ml > ∑ HCH (α -, γ -, β -, and δ -HCH) 0.014 ng/ml > aldrin and dieldrin 0.007 ng/ml > heptachlor and heptachlor epoxide 0.0068 ng/ml > endrin and endrin aldehyde 0.005 ng/ml > methoxychlor 0.001 ng/ml, respectively. Using the worst-case scenario defined as the reasonable maximum exposure (RME) to assess the potential cancer risk, five OCPs (dieldrin, 4,4′ -DDT, β -HCH, heptachlor, and heptachlor epoxide) may pose a risk of concern on a lifetime human carcinogenesis greater than one in a million.     

Body size changes in elite junior rowers: 1997 to 2007

The aim of this study was to determine whether elite international junior rowers in 2007 were heavier and taller than those evaluated in 1997, and to compare this change among finalists and non-finalists, and sweep rowers and scullers. Body weight and height data obtained by a questionnaire from a total of 398 rowers (42% female, 58% male) at the Junior World Rowing Championships in Beijing, People's Republic of China, in 2007 (65.9% of all competitors), were compared with data from 603 rowers measured at the Junior World Rowing Championships in Hazewinkel, Belgium in 1997 (36.5% female, 63.5% male, representing 90% and 89% of all competitors, respectively, by gender). Male and female rowers in 2007 were significantly taller compared to those in 1997 (1.0 cm, p = 0.009 and 2.1 cm, p < 0.001, respectively; one-sample t-test). No statistically significant difference was found for body mass. The finalists and sweep rowers were taller and heavier compared to nonfinalists and scullers at both Championships respectively. The heights of elite level junior rowers increased significantly over the decade. The finalists at World Junior Rowing Championships were again taller and heavier compared to the nonfinalists.     

Drug related deaths in the Split-Dalmatia County 1997-2007

Drug overdoses are a major cause of mortality for drug users and, in many countries, are the leading cause of death in this group. The aim of the present study is to explore the frequency of all drug related deaths in the Split-Dalmatia County in the period between 1997 and 2007 and to analyze some of the characteristics of these deaths to help target preventive policies. The data on drug related deaths were collected using records from the Department of Forensic Medicine, Clinical Hospital Centre Split, University of Split, School of Medicine. There were 190 drug related deaths in the observed period of 11 years. Statistically significant difference (p = 0.004, chi2-test for trend) was found in the number of deaths in 1997 in comparison with the number of deaths in 2007. The majority of 105 (55%) the decedents were 25-34 years old, and 92.1% (175) of them were male. There was a 94% higher probability of mortality in the 25-34 years group (chi2 = 5.55, p = 0.064). Average age of all dead people was 31.01 +/- 7.59 years (median 31.0 years; range 18-49). Almost three quarters of the decedents were single and more than three fifths hadn't been employed. The most common location of death was at home. Approximately, 80% were autopsied followed by full histological and toxicological analyses. Out of all examined cases, the majority of drug related deaths (93 or 60.8%) were attributed to heroin. Heroin was the sole cause of death in 35 (22.9%) cases. Methadone was cause of death in 24 (15.7%) cases. 3.4-methylenedioxy-methamphetamine (MDMA) deaths were rare (3.3%). Cocaine deaths were also rare (1.3%). Three fifths (55.6%) of the cases involved includes multi-substance use. During the investigation there was an evident trend towards multi-substance abuse patterns. These data suggest that interventions to prevent drug related mortality should address the use of drugs such as heroin and alcohol in combination.     

Preparation of Synaptic Plasma Membrane and Postsynaptic Density Proteins Using a Discontinuous Sucrose Gradient

Neuronal subcellular fractionation techniques allow the quantification of proteins that are trafficked to and from the synapse. As originally described in the late 1960’s, proteins associated with the synaptic plasma membrane can be isolated by ultracentrifugation on a sucrose density gradient. Once synaptic membranes are isolated, the macromolecular complex known as the post-synaptic density can be subsequently isolated due to its detergent insolubility. The techniques used to isolate synaptic plasma membranes and post-synaptic density proteins remain essentially the same after 40 years, and are widely used in current neuroscience research. This article details the fractionation of proteins associated with the synaptic plasma membrane and post-synaptic density using a discontinuous sucrose gradient. Resulting protein preparations are suitable for western blotting or 2D DIGE analysis.     

Phases and domains in sphingomyelin–cholesterol membranes: structure and properties using EPR spin-labeling methods

EPR spin-labeling methods were used to investigate the order and fluidity of alkyl chains, the hydrophobicity of the membrane interior, and the order and motion of cholesterol molecules in coexisting phases and domains, or in a single phase of fluid-phase cholesterol/egg-sphingomyelin (Chol/ESM) membranes with a Chol/ESM mixing ratio from 0 to 3. A complete set of profiles for these properties was obtained for the liquid-disordered (l _d) phase without cholesterol, for the liquid-ordered (l _o) phase for the entire region of cholesterol solubility in this phase (from 33 to 66 mol%), and for the l _o-phase domain that coexists with the cholesterol bilayer domain (CBD). Alkyl chains in the l _o phase are more ordered than in the l _d pure ESM membrane. However, fluidity in the membrane center is greater. Also, the profile of hydrophobicity changed from a bell to a rectangular shape. These differences are enhanced when the cholesterol content of the l _o phase is increased from 33 to 66 mol%, with clear brake-points between the C9 and C10 positions (approximately where the steroid-ring structure of cholesterol reaches into the membrane). The organization and motion of cholesterol molecules in the CBD are similar to those in the l _o-phase domain that coexists with the CBD.     

Phase-separation and domain-formation in cholesterol-sphingomyelin mixture: pulse-EPR oxygen probing

Membranes made of Chol/ESM (cholesterol/egg sphingomyelin) mixtures were investigated using saturation-recovery electron paramagnetic resonance spin-labeling methods, in which bimolecular collisions of relaxation agents (oxygen or nickel ethylenediamine diacetic acid) with spin labels are measured. Liquid-disordered (l_d) and liquid-ordered (l_o) phases, and cholesterol bilayer domains (CBDs) were discriminated and characterized by profiles of the oxygen transport parameter (OTP). In the l_d phase, coexisting with the l_o phase, the OTP profile is bell-shaped and lies above that in the pure ESM membrane. Changes in the OTP profile across the l_o phase are complex. When the l_o phase coexists with the l_d phase, the OTP profile is similar to that across the pure ESM membrane but with a steeper bell shape. With an increase in cholesterol concentration (up to the cholesterol-solubility threshold), the profile becomes rectangular, with low OTP values from the membrane surface to the depth of C9, and high values in the membrane center. This approximately threefold increase in the OTP occurs at the depth at which the rigid ring structure of cholesterol is immersed. Further addition of cholesterol and the formation of the CBD does not affect the OTP profile across the l_o phase. OTP values in the CBD are significantly lower than in the l_o phase.     

Shunt in the diagnosis of initial lung lesion in smokers

Cigarette smoking is an important risk factor for all respiratory tract diseases. Unfortunately, the symptoms develop slowly, thus patients feel the consequences of the slowly developing inflammation too late. The inflammation first develops in the area of respiratory bronchioles. In this stage, the disease is asymptomatic. The study included a sample of 31 smokers, mean age 36.38 years, with normal spirometry indices, acid-base status and arterial blood gases. The mean smoking index was 11.28 smoking/years. All subjects were healthy, without any subjective health problems or disease indicators. The aim was to define dead lung area (V/Q) as an early indicator of changes in smokers. Study results demonstrated the mean shunt value in smokers of 8.25%, which showed positive correlation with smoking. The shunt size yielded negative correlation with the forced expiratory volume in one second and midexpiratory flow in smokers. In conclusion, determination of lung shunt is a simple method that is sensitive enough in the diagnosis of initial lung lesion due to cigarette smoking.     

A modular approach to assembly of totally synthetic self-adjuvanting lipopeptide-based vaccines allows conformational epitope building

The technology described here allows the chemical synthesis of vaccines requiring correctly folded epitopes and that contain difficult or long peptide sequences. The final self-adjuvanting product promotes strong humoral and/or cell-mediated immunity. A module containing common components of the vaccine (T helper cell epitope and the adjuvanting lipid moiety S-[2,3-bis(palmitoyloxy)propyl]cysteine) was assembled to enable a plug and play approach to vaccine assembly. The inclusion within the module of a chemical group with chemical properties complementary and orthogonal to a chemical group present in the target epitope allowed chemoselective ligation of the two vaccine components. The heat-stable enterotoxin of enterotoxigenic Escherichia coli that requires strict conformational integrity for biological activity and the reproductive hormone luteinizing hormone-releasing hormone were used as the target epitopes for the antibody vaccines. An epitope from the acid polymerase of influenza virus was used to assemble a CD8(+) T cell vaccine. Evaluation of each vaccine candidate in animals demonstrated the feasibility of the approach and that the type of immune response required, viz. antibody or cytotoxic T lymphocyte, dictates the nature of the chemical linkage between the module and target epitope. The use of a thioether bond between the module and target epitope had little or no adverse effect on antibody responses, whereas the use of a disulfide bond between the module and target epitope almost completely abrogated the antibody response. In contrast, better cytotoxic T lymphocyte responses were obtained when a disulfide bond was used.