Altered Platelet Monoamine Oxidase-B Activity in Idiopathic Parkinson’s Disease

A case-control study was undertaken to investigate the status of platelet monoamine oxidase-B (MAO-B) activity in Indian cases of idiopathic Parkinson’s disease. A significant increase in the activity of platelet MAO-B was observed in Parkinson’s cases (n = 26) as compared to controls (n = 26). No significant change in the activity of the enzyme was observed while the data was analysed with respect to age, sex and duration of disease. A trend of decrease in platelet MAO-B activity was observed in Parkinson’s cases with respect to stage although the change was not significant. No correlation in platelet MAO-B activity was observed with respect to age and sex in the control subjects. Parkinson’s cases treated with L-DOPA and MAO-B inhibitor exhibited decreased platelet MAO-B activity as compared to drug naive cases and those treated with L-DOPA alone. Interestingly, Parkinson’s cases treated with L-DOPA and amantadine also had lower platelet MAO-B activity as compared to drug naive cases and those treated with L-DOPA alone. Activity of platelet MAO-B in Parkinson’s patients was increased in naive cases and those treated with L-DOPA alone or in combination with other drugs compared to controls. The results of the present study indicate that phenotypic activity of platelet MAO-B is high in Indian Parkinson’s cases. Further, action mechanism of drugs used in the treatment of Parkinson’s disease could be understood by assay of platelet MAO-B activity. It is an interesting observation and may be looked further in large number of cases.     

The Pivotal Role of Astrocytes in the Metabolism of Iron in the Brain

Iron is essential for the normal functioning of cells but since it is also capable of generating toxic reactive oxygen species, the metabolism of iron is tightly regulated. The present article advances the view that astrocytes are largely responsible for distributing iron in the brain. Capillary endothelial cells are separated from the neuropil by the endfeet of astrocytes, so astrocytes are ideally positioned to regulate the transport of iron to other brain cells and to protect them if iron breaches the blood-brain barrier. Astrocytes do not appear to have a high metabolic requirement for iron yet they possess transporters for transferrin, haemin and non-transferrin-bound iron. They store iron efficiently in ferritin and can export iron by a mechanism that involves ferroportin and ceruloplasmin. Since astrocytes are a common site of abnormal iron accumulation in ageing and neurodegenerative disorders, they may represent a new therapeutic target for the treatment of iron-mediated oxidative stress.     

Survival and growth of two heterotrophic hydrothermal vent archaea, <Emphasis Type="Italic">Pyrococcus</Emphasis> strain GB-D and <Emphasis Type="Italic">Thermococcus fumicolans</Emphasis>, under low pH and high sulfide concentrations in combination with high temperature and pressure regimes

Growth and survival of hyperthermophilic archaea in their extreme hydrothermal vent and subsurface environments are controlled by chemical and physical key parameters. This study examined the effects of elevated sulfide concentrations, temperature, and acidic pH on growth and survival of two hydrothermal vent archaea (Pyrococcus strain GB-D and Thermococcus fumicolans) under high temperature and pressure regimes. These two strains are members of the Thermococcales, a family of hyperthermophilic, heterotrophic, sulfur-reducing archaea that occur in high densities at vent sites. As actively growing cells, these two strains tolerated regimes of pH, pressure, and temperature that were in most cases not tolerated under severe substrate limitation. A moderate pH of 5.5–7 extends their survival and growth range over a wider range of sulfide concentrations, temperature and pressure, relative to lower pH conditions. T. fumicolans and Pyrococcus strain GB-D grew under very high pressures that exceeded in-situ pressures typical of hydrothermal vent depths, and included deep subsurface pressures. However, under the same conditions, but in the absence of carbon substrates and electron acceptors, survival was generally lower, and decreased rapidly when low pH stress was combined with high pressure and high temperature. Electronic supplementary material Supplementary material is available in the online version of this article at and is accessible for authorized users.     

Influence of habitat complexity and landscape configuration on pollination and seed-dispersal interactions of wild cherry trees

Land-use intensification is a major cause for the decline in species diversity in human-modified landscapes. The loss of functionally important species can reduce a variety of ecosystem functions, such as pollination and seed dispersal, but the intricate relationships between land-use intensity, biodiversity and ecosystem functioning are still contentious. Along a gradient from forest to intensively used farmland, we quantified bee species richness, visitation rates of bees and pollination success of wild cherry trees (Prunus avium). We analysed the effects of structural habitat diversity at a local scale and of the proportion of suitable habitat around each tree at a landscape scale. We compared these findings with those from previous studies of seed-dispersing birds and mammals in the same model system and along the same land-use gradient. Bee species richness and visitation rates were found to be highest in structurally simple habitats, whereas bird species richness—but not their visitation rates—were highest in structurally complex habitats. Mammal visitation rates were only influenced at the landscape scale. These results show that different functional groups of animals respond idiosyncratically to gradients in habitat and landscape structure. Despite strong effects on bees and birds, pollination success and bird seed removal did not differ along the land-use gradient at both spatial scales. These results suggest that mobile organisms, such as bees and birds, move over long distances in intensively used landscapes and thereby buffer pollination and seed-dispersal interactions. We conclude that measures of species richness and interaction frequencies are not sufficient on their own to understand the ultimate consequences of land-use intensification on ecosystem functioning.     

Serum Macroelement and Microelement Concentrations in Patients with Polycystic Ovary Syndrome: a Cross-Sectional Study

Polycystic ovarian syndrome (PCOS) is one of the most common endocrine diseases. However, its pathogenesis is unclear. We aim to explore the potential relationships between serum macroelements/microelements and PCOS. A total of 1137 women were involved in the current study. PCOS was defined according to ESHRE/ASRM, and complete blood samples were collected. Serum macroelements (calcium and magnesium) and microelements (copper, zinc, and iron) were assayed through atomic absorption spectrophotometry. PCOS patients had significantly higher copper concentrations than patients without PCOS (P < 0.001). By contrast, PCOS patients had lower serum calcium levels than patients without PCOS (P < 0.001). No significant differences were observed in the levels of serum zinc, magnesium, and iron between PCOS and non-PCOS patients. PCOS patients with acne had higher magnesium levels than those without acne (P = 0.020), and PCOS patients with hirsutism had lower magnesium levels than those without hirsutism (P = 0.037). High serum copper and low calcium levels may be correlated with PCOS. Magnesium concentrations are correlated with acne and hirsutism in PCOS patients. These results provide clues to explore the mechanism of PCOS and guidance for element treatments in PCOS patients.     

Effects of Nanoparticle Shape and Size on Optical Properties of LaB<Subscript>6</Subscript>

The optical response of lanthanum hexaboride (LaB₆) nanoparticles has been investigated by both theoretically and experimentally. The LaB₆ nanoparticles obtained by solid-state reaction could avoid serious surface oxidization and exhibit excellent optical performance. The discrete dipole approximation (DDA) has been used to investigate the optical response of LaB₆ nanoparticles with different sizes and different shapes. The calculation results coincide with the experimental results and reveal that the largest extinction peak value appears at 60 nm for cubic particles and 40 nm for spherical particles, respectively. Our calculation results show that the existence of the largest extinction peak value is not only due to the surface oxides but also relate to the particle shape of LaB₆ compound. In addition, the LaB₆ nanoparticles with cubic and spherical shapes exhibit different optical responses, and the cubic particles exhibit stronger near infrared (NIR) extinction than spherical particles. With increasing particle size, the extinction peak value of spherical particle decreases more rapidly than that of cubic ones.     

Genetically stable cell lines of cucumber for the large-scale production of diploid somatic embryos

For the initiation of embryogenic cucumber ( Cucumis sativus L.) cell lines, from excised radicles, directly in liquid medium, the culture regime, explant density and type and concentration of hormones were adjusted so that pro-embryogenic masses (PEMs) were formed within about 8 weeks. The established cucumber cell lines were maintained tor several years without loss of embryogenic and genetic stability. The ploidy level of somatic embryos from different cucumber eell lines was either diploid or tetraploid and depended on the ploidy level of Ihe cell line. Cucumber cell lines that produced only diploid embryos were obtained by selecting completely diploid explant material and growing it in the dark during the initiation phase. Mixoploid explains could lead to tetraploid or mixoploid ceil lines. Isolation and additional selection and subculturing of single PEMs resulted in either completely diploid or tetraploid cell lines, indicating that all cells of individual PEMs are either diploid or tetraploid. The ernbryogenic cucumber cell Imes, differing only in ploidy level, were indistinguishable in growth rate and embryogetiic potential and were genetically stable over several years.     

Isolation and characterization of a halotolerant <Emphasis Type="Italic">Bacillus</Emphasis><Emphasis Type="Italic">subtilis</Emphasis> BBK-1 which produces three kinds of lipopeptides: bacillomycin L,plipastatin, and surfactin

Twenty-three halotolerant and biosurfactant producing strains were collected from salty conditions in central Thailand. One of the strains designated BBK-1 produced the biosurfactants with the highest activity. BBK-1 was isolated from fermented foods and was identified as B. subtilis based on its physiological characteristics and 16S rRNA gene sequence. We show that the strain grows in media containing NaCl up to 16% (w/v) and produces biosurfactants in NaCl up to 8%. We found that B. subtilis BBK-1 produces three kinds of surface-active lipopeptides simultaneously. By their respective molecular weights and amino acid compositions, it is indicated that these lipopeptides are bacillomycin L, plipastatin, and surfactin. In order to analyze the production mechanism of lipopeptides further in the strain, a generally important biosynthetic gene encoding 4'-phosphopantetheinyl transferase was cloned and sequenced. The gene existed in a single copy in the genome and the deduced amino acid sequence was almost identical to that of Lpa-14 from B. subtilis strain RB14, which co-produces iturin A and surfactin.