Gel electrophoresis of human sperm: a simple method for evaluating sperm protein quality

Background

The limitations of conventional sperm analyses have highlighted the need for additional means of evaluating sperm quality.

Methods

In a study of a cohort of 245 men with known conventional sperm parameters, one-dimensional PAGE was used to monitor protein content and quality in samples from individual ejaculates.

Results

The sperm protein content varied markedly from sample to another, especially in the high-molecular-weight range. The intensity of the 80–110 kDa bands was correlated with progressive motility (r?=?0.15, p?=?0.015) and was significantly higher (p?=?0.0367) in the group of men with conventional parameters above the World Health Organization’s 2010 reference values than in the group with at least one subnormal parameter (i.e. semen volume, sperm concentration, sperm count per ejaculate, progressive motility, proportion of normal forms or multiple anomaly index below the lower reference value). Using mass spectrometry, the 80–110 kDa bands were found to correspond primarily to three proteins from the flagellum’s fibrous sheath: A-kinase anchor protein 4, A-kinase anchor protein 3, and spermatogenic cell-specific type 1 hexokinase.

Conclusion

One-dimensional PAGE constitutes a simple, rapid, reliable, inexpensive method for analyzing proteins associated with sperm motility in individual human ejaculates.

     

Essential oils against multidrug resistant gram-negative bacteria

Multi-drug resistant uropathogens are responsible for urinary tract infections. The antibacterial activity of seven essential oils, oregano, thyme, clove, arborvitae, cassia, lemongrass, tea tree) was investigated by agar diffusion method, followed by determination of minimum inhibitory (MIC) and bactericidal (MBC) concentrations against five multidrug resistant isolates namely Pseudomonas aeruginosa, Escherichia coli, Enterobacter cloaceae, Morganella morganii, Proteus mirabilis. Oregano, thyme, cassia had antibacterial activity with inhibition zones ranging 25–39 mm; clove, arborvitae, tea tree and lemongrass 12–15 mm. The essential oils showed antibacterial activities with MICs ranged from 0.005% (w/v) to 0.5% (w/v). Thyme had the same MIC and MBC on all strains. The effects of the vapors of the essential oils were also tested by placing the oils on the underside of the Petri dish lid. Thyme, oregano and cassia essential oils strongly inhibited the growth of the clinical strains of bacteria tested in vapor phase. This study demonstrates the potential of investigated essential oils as natural alternatives for further application in hospital therapies in order to retard or inhibit the bacterial growth. For the first time antibacterial effects of essential oils (clove, arborvitae, tea tree, lemongrass, and cassia) were evaluated against Enterobacter cloaceae and Morganella morganii clinical isolates.     

Effects of Warming and Nitrogen Addition on Plant Photosynthate Partitioning in an Alpine Meadow on the Tibetan Plateau

Quantifying plant carbon (C) allocation among different pools is critical for understanding and predicting how C turnover responds to global climate change in terrestrial ecosystems. A field experiment with increasing warming and nitrogen (N) was established to investigate interactive effects on plant C allocation in alpine meadows. Open-top chambers (OTCs) were used to simulate warming. In OTCs, daytime air and soil temperature at 5 cm depth increased by 2.0 and 1.6 °C, respectively, compared with ambient conditions, but soil moisture at 5 cm depth decreased by 4.95% (v/v) from 2012 to 2014. Warming reduced aboveground biomass by 38, 36, and 43% in 2012, 2013, and 2014, respectively, and increased belowground biomass by 64% and 29% in 2013 and 2014, respectively, and the root-to-shoot ratio was significantly increased. Specifically, warming increased the proportion of plant roots in the deep layers (10–20 cm). Both N addition and its combination with warming substantially enhanced belowground biomass. Pulse-labeling experiments for ¹³C revealed that warming reduced the translocation of assimilated C to shoots by 8.8% (38.7% in warming, and 47.5% in the control [CK]), and increased the allocation to root by 12.2% (55.5% in warming, and 43.3% in CK) after 28 days labeling. However, N addition increased the proportion of assimilated C allocated to shoots by 6.5% (54.0% in N addition, and 47.5% in CK), whereas warming combined with N addition reduced this proportion by 10.9%. A decline in soil water content in the surface layer may be the main cause of plants allocating more newly fixed photosynthate to roots. Therefore, plants promoted root growth to draw water from deeper soil layers (10–20 cm). We concluded that climate warming will change the allocation patterns of plant photosynthates by affecting soil water availability, whereas N addition will increase plant photosynthates aboveground in alpine meadows and thus will significantly affect C turnover under future climate change scenarios.

     

Aldolase B-Mediated Fructose Metabolism Drives Metabolic Reprogramming of Colon Cancer Liver Metastasis

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“Primeval forest relict beetles” of Central Europe: a set of 168 umbrella species for the protection of primeval forest remnants

Identification of forest stands with priority for the conservation of biodiversity is of particular importance in landscapes with a long cultural and agricultural history, such as Central Europe. A group of species with a high indicator value for the naturalness of forest ecosystems are saproxylic insects. Some of these species, especially within the order Coleoptera, have been described as primeval forests relicts. Here, we compiled a list of 168 “primeval forest relict species” of saproxylic beetles based on expert knowledge. These species can serve as focal and umbrella species for forest conservation in Central Europe. They were selected because of their dependence on the continuous presence of primeval forest habitat features, such as over-mature trees, high amounts of dead wood, and dead wood diversity, as well as their absence in managed Central European forests. These primeval forest relict species showed a moderately strong clumping pattern within the phylogeny of beetles, as indicated by phylogenetic signal testing using the D-statistic. When we controlled for phylogenetic relatedness, an ordinal linear model revealed that large body size and preference for dead wood and trees of large diameter are the main characteristics of these species. This list of species can be used to identify forest stands of conservation value throughout Central Europe, to prioritize conservation and to raise public awareness for conservation issues related to primeval forests.     

The effects of phylogeny,life-history traits and altitude on the carbon,nitrogen, and phosphorus contents of seeds across 203 species from an alpine meadow

Seed reserves are very important to the earlier growth and survival of plants, and its variation in nutrient contents might make species to form different germination or seedlings growth strategies. Here, 203 species collected from an alpine meadow on the northeastern Qinghai–Tibet plateau were used to test the effects of phylogenetic groups, life-history traits, and altitude on carbon (C), nitrogen (N) and phosphorus (P) contents of seeds across species. The results showed that (1) seeds of Brassicaceae had the highest C content, those of Fabaceae had the highest N content, and Asteraceae had the highest P content, and family explained independently 32.7%, 46.4%, and 17.9% of the variation in C, N, and P contents of seeds, respectively; (2) the smaller seeds tended to have higher C and P contents, and seed mass explained independently 2.5% of variation in C, 4.3% in N, and 8.1% in P contents; (3) N content was explained 1% independently by life form, seeds N content of perennials was significantly higher than that of annals, but seeds C and P contents had non-significant difference between them; (4) seeds of wind-adapted species had higher N and P contents, and dispersal mode explained independently 1.7% of variation in C, 1.6% in N, and 5.6% in P contents; (5) seeds from high altitude had the highest N and P contents, and altitude explained independently 4.3% of the variation in N and 4% in P contents.     

Nitrogen‐Doped Wrinkled Carbon Foils Derived from MOF Nanosheets for Superior Sodium Storage

Preparation of hierarchical carbon nanomaterials from metal?organicframeworks (MOFs) offers immense potential in the improvement of energy density, tunability, and stability of functional materials for energy storage and conversion. How interconnected nitrogen (N)‐doped wrinkled carbon foils derived from MOF nanosheets can serve as high‐performance sodium storage materials due to their multiscale porous structure is shown here. The novel N‐doped carbon nanomaterials are synthesized through the pyrolysis of 2D Mn‐based MOFs, which are produced through the assistance of monodentate ligands to enable the planar growth of MOFs. Subsequent acid etching creates hierarchical pores and channels to allow rapid ion transport. The resulting materials achieve high‐rate capability (165 and 150 mA h g^?1 at current densities of 8 and 10 A g^?1, respectively) and high stability (capacity retention 72.8% after 1000 cycling at 1.0 A g^?1), when they are used as anode in sodium‐ion capacitors.     

The effect of inter- and intra-specific competition on survival and growth rate of native juvenile noble crayfish <Emphasis Type="Italic">Astacus astacus</Emphasis> and alien spiny-cheek crayfish <Emphasis Type="Italic">Orconectes limosus</Emphasis>

Juvenile noble crayfish, Astacus astacus and spiny-cheek crayfish, Orconectes limosus were reared from the 2nd and the 3rd developmental stage (i.e. since the stage of independence), respectively, until the end of the growing season. The first period revealed very low survival rate of O. limosus in the communal stock (7 ± 6.2%), probably caused by predation of A. astacus. Separately reared O. limosus proved significantly higher survival rate (49 ± 9.2%) than those in the communal stock with A. astacus. The latter species also showed the highest survival rate in this case (90 ± 7.1%). This was not found to differ from the survival rate of separately reared noble crayfish (86 ± 3.1%). In general, both the significant effect of bigger size of A. astacus than that of O. limosus and higher intra-specific cannibalism of O. limosus were reflected during the first phase of rearing. Size and weight of both species were equivalent 11 weeks after hatching (8 weeks of rearing). The higher cumulative survival rate was reached in the intraspecific culture of A. astacus (90%) while low cumulative survival of both species was found in communal stock (less than 50%) in the second phase of rearing. At the end of the growing season, 19-week-old O. limosus attained a higher mean size and weight but were more variable in the group (29.3 ± 5.17 mm and 616.4 ± 412.53 mg) than A. astacus (21.2 ± 1.82 mm and 229.9 ± 59.45 mg). Single and communal stock did not differ. Growth of O. limosus was much faster than that of A. astacus.