Relationship between tryptophan and serotonin concentrations in postmortem human brain

The present study was planned to test a recent observation of positive correlation between tryptophan and 5-hydroxyindole concentrations in postmortem human hypothalamic samples. Four other brain areas were studied, but no significant correlations were observed between tryptophan and serotonin or 5-hydroxyindoleacetic acid concentrations, except in the nucleus accumbens samples of a suicide victim group. A possible in vivo correlation may have been obscured by postmortem changes. The use of tryptophan concentrations as an index for normalising postmortem brain serotonin data is not supported by the present results.     

Investigation of the dark interaction between furocoumarins and DNA

The complexes between some furocoumarins and DNA have been studied using various physicochemical techniques. Flow-dichroism measurements data strongly support the intercalation of the planar furocoumarin molecules between two base pairs of duplex DNA. The equilibrium dialysis and spectrophotometric data show relatively low values of the association constants of the complexes and a small number of molecules able to intercalate in DNA, thus indicating that furocoumarins have a relatively low affinity for DNA in the complex formation. The biological and photobiological consequences connected with these results are discussed.The binding curves obtained using some polynucleotides and various DNA samples having different composition with regard to base pairs, have shown that the regions of the macromolecule having alternate sequences of purine and pyrimidine represent sites useful for intercalation. No preference has been observed for A-T or G-C.     

Determination of urine catecholamines by capillary electrophoresis with dual-electrode amperometric detection

Demonstrated in this study is that without pretreatment and preconcentration nanomolar-level catecholamines in human urine samples can be quantitatively determined with ease by utilizing capillary electrophoresis coupled with amperometric detection. The detector employs a parallel-opposed dual-electrode scheme assembled with an on-capillary electrode and a disk electrode and takes advantage of the redox cycling of analytes between the two working electrodes to improve the limit of detection. The matrix effect of urine samples significantly decreases the detection sensitivity from that obtained in standard solutions. Therefore, calibration curves derived from standard solutions cannot be used in quantitative determination of catecholamines. Methods of standard addition and internal standard have been studied. The results suggest that isoproterenol is a good internal standard to facilitate the measurements of dopamine, epinephrine, and norepinephrine in human urine samples.     

PGM1 and TF subtypes and C3 polymorphisms in Continental Italy and Sardinia. Data on the world distribution of these genetic markers

PGM1, TF and C3 polymorphisms have been examined in two Italian samples, collected in continental Italy and in Sardinia (Cagliari). The PGM1 and TF subtypes were determined by isoelectric focusing while the C3 was studied by conventional methods. A significant difference in the gene frequencies of PGM1 and TF systems between our two samples has been observed. In addition, data on the world distribution of PGM1, TF and C3 polymorphisms have been presented.     

Complex formation of bovine serum albumin with a poly(ethylene glycol) lipid conjugate

In this work, we report the formation of complexes by self-assembly of bovine serum albumin (BSA) with a poly(ethylene glycol) lipid conjugate (PEG2000-PE) in phosphate saline buffer solution (pH 7.4). Three different sets of samples have been studied. The BSA concentration remained fixed (1, 0.01, or 0.001 wt % BSA) within each set of samples, while the PEG2000-PE concentration was varied. Dynamic light scattering (DLS), rheology, and small-angle X-ray scattering (SAXS) were used to study samples with 1 wt % BSA. DLS showed that BSA/PEG2000-PE aggregates have a size intermediate between a BSA monomer and a PEG2000-PE micelle. Rheology suggested that BSA/PEG2000-PE complexes might be surrounded by a relatively compact PEG-lipid shell, while SAXS results showed that depletion forces do not take an important role in the stabilization of the complexes. Samples containing 0.01 wt % BSA were studied by circular dichroism (CD) and ultraviolet fluorescence spectroscopy (UV). UV results showed that at low concentrations of PEG-lipid, PEG2000-PE binds to tryptophan (Trp) groups in BSA, while at high concentrations of PEG-lipid the Trp groups are exposed to water. CD results showed that changes in Trp environment take place with a minimal variation of the BSA secondary structure elements. Finally, samples containing 0.001 wt % BSA were studied by zeta-potential experiments. Results showed that steric interactions might play an important role in the stabilization of the BSA/PEG2000-PE complexes.     

低能铁离子束辐照氨基酸衍生物的红外光谱结构表征

利用傅里叶变换红外光谱（FTIR）技术研究了能量为110keV的Fe^ 离子束辐照L（ ）-半胱氨酸盐酸盐单晶水合物固态样品的结构变化情况。对辐照样品的两次红外光谱分析结果有所不同,表明固态样品不同部位受低能铁离子束作用后可发生不同的分子改性;但二者又具有一定的相似性,都反映了原分子中氨基、羧基和巯基等基团的受损及硝基和酰胺基团等的生成。     

Determination by capillary gas liquid chromatography of nitrosamine in partially altered food

The nitrosamines have been extensively studied for their toxicity. Their formation in the foods containing nitrous and nitric derivatives is favoured by the presence of suitable substrata. In the present work have been used column and capillari GL Chromatography for the determination of some nitrosamines in altered foods. The results obtained by applying the suggested procedure to a number of altered samples have been very encouraging.     

How is mRNA expression predictive for protein expression? A correlation study on human circulating monocytes

A key assumption in studying mRNA expression is that it is informative in the prediction of protein expression. However, only limited studies have explored the mRNA-protein expression correlation in yeast or human tissues and the results have been relatively inconsistent. We carried out correlation analyses on mRNA-protein expressions in freshly isolated human circulating monocytes from 30 unrelated women. The expressed proteins for 71 genes were quantified and identified by 2-D electrophoresis coupled with mass spectrometry. The corresponding mRNA expressions were quantified by Affymetrix gene chips. Significant correlation ( r =0.235, P <0.0001) was observed for the whole dataset including all studied genes and all samples. The correlations varied in different biological categories of gene ontology. For example, the highest correlation was achieved for genes of the extracellular region in terms of cellular component ( r =0.643, P <0.0001) and the lowest correlation was obtained for genes of regulation ( r =0.099, P=0.213) in terms of biological process. In the genome, half of the samples showed significant positive correlation for the 71 genes and significant correlation was found between the average mRNA and the average protein expression levels in all samples ( r =0.296, P <0.01). However, at the study group level, only five studied genes had significant positive correlation across all the samples. Our results showed an overall positive correlation between mRNA and protein expression levels. However, the moderate and varied correlations suggest that mRNA expression might be sometimes useful, but certainly far from perfect, in predicting protein expression levels.     

Phytosociology and soil properties of Corylus avellana coppices on the coast of western Norway

About 400 relevés of Corylus avellana coppices along the coast of western Norway have been taken, and their phytosociology have been investigated. Soil samples from some of the stands have been studied. The hazel coppices found belonged to the associations Conopodio-Ulmetum, Primulo-Ulmetum and Melico-Betuletum. Within Conopodio-Ulmetum, one typical variant and one rich variant with much Epipactis showed significant differences between the three vegetation units. The soil of the Epipactis variant was the most basic and richest in nutrients, while the soil of Melico-Betuletum was the most acid and poorest in nutrients.     

Biosorbents prepared from wood particles treated with anionic polymer and iron salt: effect of particle size on phosphate adsorption

Biomass-based adsorbents have been widely studied as a cost-effective and environmentally-benign means to remove pollutants and nutrients from water. A two-stage treatment of aspen wood particles with solutions of carboxymethyl cellulose (CMC) and ferrous chloride afforded a biosorbent that was effective in removing phosphate from test solutions. FTIR spectroscopy of the biosorbent samples showed a decrease in the intensity of the carboxylate signal coinciding with a decrease in particle size. Elemental analysis results showed the iron content of both the biosorbent samples, and wood particles treated with ferrous chloride alone, to also decrease with particle size. The relationship between iron content and particle size for the biosorbent samples appeared to be a function of both the amount of CMC-Fe complex and the efficiency of removing free iron ions after treating. Sorption testing results showed a strong linear correlation between the phosphorous uptake capacities and the iron contents of the samples adjusted for losses of iron during testing. As anticipated, pretreating with the anionic polymer provided additional sites to complex iron and thereby imparted a greater phosphorous uptake capacity. Although the larger wood particles provided a greater amount of iron for phosphate removal, smaller wood particles may be preferred since they afforded the lowest release of iron relative to the amount of phosphate removed.     

Karyological studies of some orophyte taxa of the genus Ranunculus L.from the Iberian Peninsula

The somatic chromosome number and detailed chromosome morphology have been studied in populations of seven species of Ranunculus, namely Ranunculus alpestris L., R.glacialis L., R. Thora L., R.seguieri Vill., R. Aconitifolius L., R.platanifolius L. And R. Acetosellifolius Boiss., from the Iberian Peninsula. Diploid levels have been found for these species in the samples studied. From the karyological data (karyograms, idiograms and asymmetry) relationships between these taxa are discussed.     

Testate amoebae inhabiting middle taiga bogs in Western Siberia

The population of testate amoebae from the most typical middle taiga bogs of Western Siberia have been studied. More than one hundred (103) species and intraspecific taxons of testate amoebae have been revealed in recent surface samples. The relation between ecological characteristics of habitats and the composition of a Protozoa population has been demonstrated. The ecological preferences of species concerning the index of wetness, ash level, and acidity have been revealed. Using the correspondence analysis, the ecological optimums and the tolerance of species and intraspecific taxons of testate amoebae have been established.     

Population affinities assessed by dermatoglyphic and hemogenetic variables

13 dermatoglyphic variables have been studied in eight population samples (five smaller isolated and three larger populations) to identify the possible differences between the larger and the smaller isolated populations. The data and neighbor joining trees for the dermatoglyphic variables show distinct differences between males and females. The isolated population of the Lutheran Mountains is clearly separated from the other populations. Combining the results of dermatoglyphic and 12 hemogenetic variables (only for six populations) the male and female trees are nearly identical. The three isolated populations are clearly separated, whereas the larger ones show smaller distances.     

The susceptibility of pure tubulin to high magnetic fields: a magnetic birefringence and x-ray fiber diffraction study.

The orientational behavior of microtubules assembled in strong magnetic fields has been studied. It is shown that when microtubules are assembled in a magnetic field, they align with their long axis parallel to the magnetic field. The effect of several parameters known to affect the microtubule assembly are investigated with respect to their effect on the final degree of alignment. Aligned samples of hydrated microtubules suitable for low-resolution x-ray fiber diffraction experiments have been produced, and the results obtained from the fiber diffraction experiments have been compared with the magnetic birefringence experiments. Comparisons with earlier fiber diffraction work and small-angle x-ray solution scattering experiments have been made.     

Microfilarial infections associated with body mass loss of Village Weavers Ploceus cucullatus

Haemoparasitic infections in wild birds have been widely studied in order to understand parasite–host relation- ships, but our understanding of their impact on the host's fitness is still limited. In this study, we quantified the associations between microfilarial infections and body mass and between microfilarial infections and haemato- crit values in Village Weavers Ploceus cucullatus. We screened blood samples (thin smear and buffy coat) for the presence of haemoparasitic infections and measured haematocrit values. Fifty-seven percent of 91 individuals screened carried a microfilarial infection but, contrary to expectations, no other haemoparasitic infections were detected in the blood samples. We found a negative relationship between microfilarial infection status and body mass, but no relationship between infection status and haematocrit values. Our results suggest that microfilarial infections may be associated with body mass loss in wild birds.     

Conformational fluctuation of native-like and molten-globule-like cytochrome c observed by time-resolved hole burning

Nanosecond to millisecond conformational fluctuations of Zn-substituted cytochrome c (ZnCytc) have been studied by the time-resolved transient hole-burning method. The investigation of low-temperature dynamics has been made on the ZnCytc solution sample in a water-glycerol mixture. The conformational fluctuations in the native-like and the molten-globule (MG)-like states have been compared for the aqueous solution samples at room temperature. ZnCytc in the MG-like state has been prepared by adding 200 mM NaClO4 to the protein solution with a pH of 2.1, and the formation of the MG-like state has been confirmed by both the far-UV CD and the visible absorption spectra. The hole spectrum of ZnCytc has been found to consist of two nearly degenerate components, that is, the Qx and Qy bands. The temporal change in the Qx component hole spectrum has been extracted by fitting the observed hole spectrum to the three-Gaussian form. The experimental results for ZnCytc dissolved in a water-glycerol mixture have revealed that the conformational fluctuation of ZnCytc is suppressed around 200 K, which is nearly the same temperature as the glass-like transition point of Zn-substituted myoglobin (ZnMb) and also as the glass-transition point of the solvent. This supports the idea of the solvent-induced glass-like transition of a protein. It has been also found that at physiological temperatures the time scale of the conformational fluctuation of ZnCytc lies around a few tens of nanoseconds, which is 2-3 orders of magnitude faster than that of ZnMb. The experimental results for the aqueous solution samples have shown that the difference between the native-like and the MG-like states is not conspicuous. However, they are indicative of the appearance of the slower conformational fluctuation in the MG-like state.     

Gene pool of Buryats: Clinal variability and territorial subdivision based on data of Y-chromosome markers

The structure of the Buryat gene pool has been studied based on the composition and frequency of Y-chromosome haplogroups in eight geographically distant populations. Eleven haplogroups have been found in the Buryat gene pool, two of which are the most frequent (N1c1 and C3d). The greatest difference in haplogroup frequencies was fixed between western and eastern Buryat samples. The evaluation of genetic diversity based on haplogroup frequencies revealed that it has low values in most of the samples. The evaluation of the genetic differentiation of the examined samples using an analysis of molecular variance (AMOVA) shows that the Buryat gene pool is highly differentiated by haplotype frequencies. Phylogenetic analysis within haplogroups N1c1 and C3d revealed a strong founder effect, i.e., reduced diversity and starlike phylogeny of the median network of haplotypes that form specific subclusters. The results of a phylogenetic analysis of the haplogroups identified common genetic components for Buryats and Mongols.     

Volatile metabolites in sera of normal and diabetic patients

The profiles of volatile metabolites in serum samples from normal individuals and from individuals with diabetes mellitus with varying degrees of polyneuropathy have been studied. The transevaporator procedure was used to obtain sample extracts which were chromatographed on a highly efficient glass column coated with Silar 10C (106 m × 0.25 mm I.D.). Differences in profiles between normal subjects and diabetic subjects on no drug therapy were noticed. However, correlations between the severity of the neuropathy and the concentrations of certain ketones could not be established. Compounds present both in diabetic and normal sera have been identified by mass spectrometry.     

Anaerobic microbial associations degrading aromatic amino acids

Anaerobic microbial associations have been isolated that degrade aromatic amino acids to methane and carbon dioxide at high rates. Significant differences between the morphological, cytological, and physiological traits of cultures isolated from samples of adapted and unadapted sludge are shown. The effects of cultivation temperature, illumination, and presence of mineral nitrogen and bicarbonate in the medium upon adaptation of enrichment cultures to substrates and subsequent behavior of the anaerobic associations have been studied. Intermediate and final products of degradation of aminoaromatic compounds and the sequence of their formation in the cultures have been determined. We have also studied the effects of exogenous electron acceptors and additional carbon sources on the degradation of aminoaromatic compounds.     

Salivary agglutinins in an Indian population

Saliva samples from 239 Punjabis have been analysed for the presence of anti-A and anti-B. Agglutinins have been found to be present in 35.98 per cent of the saliva samples studied. The amount of agglutinin present varies from one individual to another. Anti-A has been found to occur more frequently than anti-B among the Punjabis and most of the other populations studied so far.