Identification of 17-18 kDa zona pellucida binding proteins from boar spermatozoa

Zona pellucida (ZP) binding proteins from boar spermatozoa were compared with antigens recognized by ACR.2 and ACR.3 monoclonal antibodies. The ZP binding proteins of 55, 53, 45 and 38 kDa are identical with various forms of boar acrosin immunologically detected by ACR.2 antibody. The ZP binding proteins of 17 and 18 kDa are recognized by ACR.3 antibody. The N-terminal amino acid sequence of the 17 kDa protein revealed that it is not derived from an acrosin molecule.     

Cercarial dermatitis caused by bird schistosomes comprises both immediate and late phase cutaneous hypersensitivity reactions

Avian schistosomes are the primary causative agent of cercarial dermatitis in humans, but despite its worldwide occurrence, little is known of the immune mechanism of this disease. Using a murine model, hosts were exposed to primary (1x) and multiple (4x) infections of Trichobilharzia regenti via the pinna. Penetration of larvae into the skin evoked immediate edema, thickening of the exposure site, and an influx of leukocytes, including neutrophils, macrophages, CD4+ lymphocytes, and mast cells. A large proportion of the latter were in the process of degranulating. After 1x infection, inflammation was accompanied by the release of IL-1beta, IL-6, and IL-12p40. In contrast, in 4x reinfected animals the production of histamine, IL-4, and IL-10 was dramatically elevated within 1 h of infection. Analysis of Ag-stimulated lymphocytes from the skin-draining lymph nodes revealed that cells from 1x infected mice produced a mixed Th1/Th2 cytokine response, including abundant IFN-gamma, whereas cells from 4x reinfected mice were Th2 polarized, dominated by IL-4 and IL-5. Serum Abs confirmed this polarization, with elevated levels of IgG1 and IgE after multiple infections. Infection with radiolabeled cercariae revealed that almost 90% of larvae remained in the skin, and the majority died within 8 days after infection, although parasites were cleared more rapidly in 4x reinfected mice. Our results are the first demonstration that cercarial dermatitis, caused by bird schistosomes, is characterized by an early type I hypersensitivity reaction and a late phase of cutaneous inflammation, both associated with a polarized Th2-type acquired immune response.     

Microgeographic genome size differentiation of the carob tree, Ceratonia siliqua, at 'Evolution Canyon', Israel

BACKGROUND AND AIMS: We tested whether the local differences in genome size recorded earlier in the wild barley, Hordeum spontaneum, at 'Evolution Canyon', Mount Carmel, Israel, can also be found in other organisms. As a model species for our test we chose the evergreen carob tree, Ceratonia siliqua. METHODS: Genome size was measured by means of DAPI flow cytometry. KEY RESULTS: In adults, significantly more DNA was recorded in trees growing on the more illuminated, warmer, drier, microclimatically more fluctuating 'African' south-facing slope than in trees on the opposite, less illuminated, cooler and more humid, 'European' north-facing slope in spite of an interslope distance of only 100 m at the canyon bottom and 400 m at the top. The amount of DNA was significantly negatively correlated with leaf length and tree circumference. In seedlings, interslope differences in the amount of genome DNA were not found. In addition, the first cases of triploidy and tetraploidy were found in C. siliqua. CONCLUSIONS: The data on C. siliqua at 'Evolution Canyon' showed that local variability in the C-value exists in this species and that ecological stress might be a strong evolutionary driving force in shaping the amount of DNA.     

Primordial proteins and HIV

Primordial proteins regulate the response of nanobacteria to variations in their environment and reinforce existing pathogenic potentials. By analyzing specific response patterns, we predicted the prevalence of nanobacteria in HIV--and in the atmosphere. A current clinical study indicates the identification of a possibly giant nanobacterial reservoir in Africa: a significant fraction of a test group (40 HIV-infected mothers and 13 babies) was infected with nanobacteria. Concurrently, a multitude of 80-300 nm nanovesicles, apparently nanobacteria, were detected in the atmosphere of the Earth. Nanobacterial infections in HIV are possibly comparable to the twin epidemics HIV and tuberculosis. Models inspired by proteomics recommend methods to inactivate nanobacteria (and other slime-producing bacteria) in the body.     

Evaluation of aminolysis of anilinothiazolinones to phenylthiocarbamoyl amino acid methyl amides as an alternative conversion method in protein sequencing.

The aminolysis of products of sequential degradation of proteins and peptides by methylamine is an alternative method of conversion of the unstable 5-alkyl-2-anilino-4-thiazolinones into the stable methyl amides of N alpha-phenylthiocarbamoyl amino acids. The volatility of methylamine permits use in the gas phase during both manual and automatic sequential degradation. Two procedures were studied: (mode A) aminolysis by methylamine in the sequencer reaction chamber after liberation of the thiazolinones by trifluoroacetic acid and (mode B) aminolysis by methylamine vapors passed through a 1-chlorobutane solution of thiazolinones in the conversion flask of the sequencer. The sequencing program was modified for both procedures by making use of the standard sequencer functions. The yields of aminolysis in the conversion flask (mode B) are comparable to those obtained by standard conversion in 25% trifluoracetic acid and the procedure does not affect the repetitive yield. Aminolysis on the glass filter (mode A) requires a major modification of the degradation process, yet gives higher yields of the degraded amino acid derivatives. A disadvantage of both procedures, especially of mode A, is the presence of N-methyl-N'-phenylthiourea in the methyl amide samples. We have not been able to achieve the expected improvement of the yields of degraded hydroxy amino acids. Therefore the replacement of acid conversion of anilinothiazolinones to phenylthiohydantiones by aminolysis for routine degradation cannot be recommended. High yields of methyl amides make aminolysis a promising candidate for the incorporation of fluorescent or other labels in the products of sequencing degradation.     

Mannitol derivate used as a marker for voltammetrically monitored transport across the blood-brain barrier under condition of locus coeruleus stimulation

1-Deoxy-1-nitro-D-mannitol (DN-Man) was used (femoral vein injection, approximate concentration in the blood 30 mmol.l-1) in pentobarbital anaesthetized rats as a promising marker detectable by differential pulse voltammetry (DPV) to study its transport across the blood-brain barrier (BBB) to the extra-cellular space of the frontoparietal cortex. DN-Man detection limit in in vitro calibrations (saline, blood) using DPV and carbon fiber microelectrodes was 0.5 mmol.l-1 with a good linearity (r = = 0.996) over the entire tested range (up to 30 mmol.l-1). The slow time-course of the rise of DN-Man signal (y = 106/(1 + (17.8/t)3)) in the cortex confirmed the functional BBB state. Electrical stimulation of the locus coeruleus (LC) (300 rectangular pulses at a frequency of 100 Hz, 1 mA, pulse duration 0.2 ms) elevated significantly DN-Man current in the cortex (to 168 +/- 59% of the control, mean +/- S.D., n = 8). The evoked permeation increase of the BBB to DN-Man was short-lasting (minutes), and the second LC stimulation (repeated 5 min after the first one) was ineffective. This fact was probably due to the reduction of DN-Man levels in blood and/or an altered response of microvessels to neurotransmitters. It was shown here that, under carefully controlled surgical and experimental conditions, DPV and DN-Man might be useful for the monitoring of the regional dynamics of BBB transport changes. The presented results also support the view that BBB transport can be influenced by LC neuronal activity.     

The binding problem in population neurodynamics: a network model for stimulus-specific coherent oscillations

A hypothesis is presented that coherent oscillatory discharges of spatially distributed neuronal groups (the supposed binding mechanism) are the result of the convergence of stimulus-dependent activity in modality-specific afferent pathways with oscillatory activity generated in unspecific sensory systems. This view is supported by simulation experiments on model networks.     

Dimerization of quercetin,Diels-Alder vs. radical-coupling approach: a joint thermodynamics,kinetics, and topological study

Quercetin is a prototypical antioxidant and prominent member of flavonoids, a large group of natural polyphenols. The oxidation of quercetin may lead to its dimerization, which is a paradigm of the more general polyphenol oligomerization. There exist two opposing mechanisms to describe the dimerization process, namely radical-coupling or Diels-Alder reactions. This work presents a comprehensive rationalization of this dimerization process, acquired from density functional theory (DFT) calculations. It is found that the two-step radical-coupling pathway is thermodynamically and kinetically preferred over the Diels-Alder reaction. This is in agreement with the experimental results showing the formation of only one isomer, whereas the Diels-Alder mechanism would yield two isomers. The evolution in bonding, occurring during these two processes, is investigated using the atoms in molecules (AIM) and electron localization function (ELF) topological approaches. It is shown that some electron density is accumulated between the fragments in the transition state of the radical-coupling reaction, but not in the transition state of the Diels-Alder process.

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Graphical Abstract Quantum chemistry calculations of the dimerization process of quercetin show that a radical coupling approach is preferred to a Diels-Alder type reaction, in agreement with experimental results. Analysis of the bonding evolution highlights the reaction mechanism.

     

Winners and losers in the wilderness: response of biodiversity to the abandonment of ancient forest pastures

Large areas of formerly oak-dominated woodlands are currently managed for timber products, and if they are used in a conservation-oriented way, they are often abandoned and left to become wilderness. We focused on the situation when an oak woodland is still partly managed as an ancient game park and partly abandoned as a nature conservation amendment. We studied this effect using a multi-taxa approach with lichens, fungi and beetles and investigated their response to the changing patterns in canopy openness, dead wood distribution and host tree conditions. The study was done in the Hradec Králové region of the Czech Republic. We found that the maintenance of canopy openness, as determined by management, was the primary driver influencing species composition. Canopy closure led to homogenization of the beetle and lichen communities and the loss of species. Fungi were mainly driven by the amount of dead wood, and abandonment favored their species richness. The creation of a new wilderness was only profitable for fungi, and the maintenance of canopy openness was an important driver for most of the studied taxa (i.e., biodiversity maintenance). Canopy openness and the presence of veteran trees could be used as an indicator of a management history that helps conserve biodiversity. Appropriate conditions for all taxa studied could be fulfilled using wood pasturing or game keeping in combination with dead tree retention.     

Comparison between prochymosin and pepsinogen from lamb and calf

1. Prochymosin (EC 3.4.23.4) and pepsinogen A (EC 3.4.23.1) from Mongolian lamb (Ovis platyurea) were purified to homogeneity by salt precipitation, gel filtration and ion-exchange chromatography. 2. Immunoelectrophoresis shows partial immunochemical identity between chymosins and pepsins from lamb and cattle, respectively. 2. Activity determinations, N-terminal amino acid sequences and amino acid compositions also show a close relationship between the proteinases from lamb and cattle. 4. Lamb prochymosin and pepsinogen are both glycosylated.