Alpha subunit variants of the human glycine receptor: primary structures, functional expression and chromosomal localization of the corresponding genes.

Two cDNAs encoding variants (alpha 1 and alpha 2) of the strychnine binding subunit of the inhibitory glycine receptor (GlyR) were isolated from a human fetal brain cDNA library. The predicted amino acid sequences exhibit approximately 99% and approximately 76% identity to the previously characterized rat 48 kd polypeptide. Heterologous expression of the human alpha 1 and alpha 2 subunits in Xenopus oocytes resulted in the formation of glycine-gated strychnine-sensitive chloride channels, indicating that both polypeptides can form functional GlyRs. Using a panel of rodent-human hybrid cell lines, the gene encoding alpha 2 was mapped to the short arm (Xp21.2-p22.1) of the human X chromosome. In contrast, the alpha 1 subunit gene is autosomally located. These data indicate molecular heterogeneity of the human GlyR at the level of alpha subunit genes.     

Membrane receptors for estrogen,progesterone, and testosterone in the rat brain: Fantasy or reality

Summary 1. There are numerous circumstantial evidence supporting the concept that steroid hormones control cellular function by means other than the nuclear receptor steroid binding mechanism. It is the intent of this report to present evidence indicating that steroids bind to specific sites in neuronal membranes.2. Some of the criteria to define steroid membrane receptors using steroid-BSA conjugates that can be radioiodinated to desired specific activity have been fulfilled for each of the three sex steroids using crude synaptosomal membrane preparations (P2 fractions) from the CNS of female and male rats. Ligand binding for each of the three steroids indicate high-affinity and high-capacity sites with distinct brain selectivity and stereospecificity. For example, 17-E-6-[¹²⁵I]BSA binds hypothalamic P2 fractions (HYP-P2) with an estimatedK _d of about 3±0.7 nM (X ± SE;n=3), whereas the cerebellum P2 (CB-P2) fractions bind the ligand with aK _d of 34±7 nM and, aB _max of 3 and 42 pmol/mg protein, respectively. Estrogen and testosterone binding fit best a one-single site, while progesterone binding sites can be best represented by a two-binding site, one high-affinity (K _d=1–2 nM) and one low affinity (K _d=62 nM), in CB-P2 fractions from intact adult female rat brain. Kinetics studies for T-3-[¹²⁵I]BSA indicate that the estimatedK _d of 30±2 nM for the olfactory bulb P2 fractions (OB-P2) from male rats is in good agreement withK _d values computed from Scatchard-derived data using the LIGAND algorithm.3. 17-E-6-[¹²⁵I]BSA binding sites are stereospecific and appears to be present as early as 5 days of age in both the OB- and the CB-P2 fractions without changes during development. In contrast, P-6-[¹²⁵I]BSA binding sites are practically absent during days 5 and 12 and appear by day 22.4. Finally, membrane receptor molecules for estrogen and progesterone have been isolated and purified by affinity chromatography and characterized by PAGE and Western blot. Microsequencing of one of the membrane estrogen binding proteins indicates that the high-affinity site corresponds to the OSCP subunit of the proton ATP synthase.5. It remains to be determined if P and T also bind to this complex enzyme or if they bind to other subunits of the family of proton ATPases. Overall the data indicate that steroid hormones conjugated to BSA are important tools to study the reality of membrane steroid receptors.     

Chromosome complement and nucleolar organization in Podophyllum hexandrum Royle

The karyomorphology of Podophyllum hexandrum Royle (2n=2x=12) is described for the first time. The haploid set comprises one metacentric, three sub-metacentric and two acrocentric chromosomes. Metacentrics are the longest and acrocentrics the smallest in the complement. Secondary constrictions are located in the short arm of two meta-/submetacentrics and in the long arm of the two acrocentric chromosomes. The number of NORs is in agreement with the number of nucleoli organized per root tip nucleus.     

The Journey from Two-Step to Multi-Step Phosphorelay Signaling Systems

BackgroundThe two-component signaling (TCS) system is an important signal transduction machinery in prokaryotes and eukaryotes, excluding animals, that uses a protein phosphorylation mechanism for signal transmission.ConclusionProkaryotes have a primitive type of TCS machinery, which mainly comprises a membrane-bound sensory histidine kinase (HK) and its cognate cytoplasmic response regulator (RR). Hence, it is sometimes referred to as two-step phosphorelay (TSP). Eukaryotes have more sophisticated signaling machinery, with an extra component - a histidine-containing phosphotransfer (HPT) protein that shuttles between HK and RR to communicate signal baggage. As a result, the TSP has evolved from a two-step phosphorelay (His–Asp) in simple prokaryotes to a multi-step phosphorelay (MSP) cascade (His–Asp–His–Asp) in complex eukaryotic organisms, such as plants, to mediate the signaling network. This molecular evolution is also reflected in the form of considerable structural modifications in the domain architecture of the individual components of the TCS system. In this review, we present TCS system''s evolutionary journey from the primitive TSP to advanced MSP type across the genera. This information will be highly useful in designing the future strategies of crop improvement based on the individual members of the TCS machinery.     

In-vitro and In-vivo management of Meloidogyne incognita (Kofoid and White) Chitwood and Rhizoctonia bataticola (Taub.) Butler in cotton using organic’s

Root-knot nematodes Meloidogyne incognita (Kofoid and White) Chitwood and Rhizoctonia bataticola (Taub.) Butler, fungus, are very dangerous root damaging pathogens. Present study was planned to establish a chemical control of these root deteriorating pathogens under lab conditions as well as in field. Maximum death rate of nematode juveniles and minimum numbers of nematode eggs hatched were recorded in plates treated with Cadusafos (Rugby® 100G) @12 g/100 ml and Cartap® (4% G) @9g/100 ml. Chemical treatment of Rhizoctonia bataticola with Trifloxystrobin + Tebuconazole (Nativo®) @0.2 g/100 ml and Mancozeb + Matalaxyl (Axiom) @0.25 g/100 ml significantly controlled the mycelial growth in plates. The best treatments tested in laboratory were applied in field as protective and curative treatments. Results proved that chemical control of root-knot nematode and root rot fungi by tested chemicals at recommended time and dose is a significant management technique under field conditions.     

Aluminium oxide nanoparticles inhibit EPS production,adhesion and biofilm formation by multidrug resistant Acinetobacter baumannii

Abstract

Acinetobacter baumannii is a biofilm forming multidrug resistant (MDR) pathogen responsible for respiratory tract infections. In this study, aluminium oxide nanoparticles (Al₂O₃ NPs) were synthesized and characterized by TEM and EDX and shown to be spherical shaped nanoparticles with a diameter < 10?nm. The minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) for the Al₂O₃ NPs ranged between 125 and 1,000?µg ml^?1. Exposure to NPs caused cellular membrane disruption, indicated by an increase in cellular leakage of the contents. Biofilm inhibition was 11.64 to 70.2%, whereas attachment of bacteria to polystyrene surfaces was reduced to 48.8 to 51.9% in the presence of NPs. Nanoparticles also reduced extracellular polymeric substance production and the biomass of established biofilms. The data revealed the non-toxic nature of Al₂O₃ NPs up to a concentrations of 120?µg ml^?1 in HeLa cell lines. These results demonstrate an effective and safer use of Al₂O₃ NPs against the MDR A. baumannii by targeting biofilm formation, adhesion and EPS production.     

Modelling root plasticity and response of narrow-leafed lupin to heterogeneous phosphorus supply

Background & Aims

Searching for root traits underpinning efficient nutrient acquisition has received increased attention in modern breeding programs aimed at improved crop productivity. Root models provide an opportunity to investigate root-soil interactions through representing the relationships between rooting traits and the non-uniform supply of soil resources. This study used simulation modelling to predict and identify phenotypic plasticity, root growth responses and phosphorus (P) use efficiency of contrasting Lupinus angustifolius genotypes to localised soil P in a glasshouse.

Methods

Two L. angustifolius genotypes with contrasting root systems were grown in cylindrical columns containing uniform soil with three P treatments (nil and 20 mg P kg^?1 either top-dressed or banded) in the glasshouse. Computer simulations were carried out with root architecture model ROOTMAP which was parameterized with root architectural data from an earlier published hydroponic phenotyping study.

Results

The experimental and simulated results showed that plants supplied with banded P had the largest root system and the greatest P-uptake efficiency. The P addition significantly stimulated root branching in the topsoil, whereas plants with nil P had relatively deeper roots. Genotype-dependent root growth plasticity in response to P supply was shown, with the greatest response to banded P.

Conclusions

Both experimental and simulation outcomes demonstrated that 1) root hairs and root proliferation increased plant P acquisition and were more beneficial in the localised P fertilisation scenario, 2) placing P deeper in the soil might be a more effective fertilisation method with greater P uptake than top dressing, and 3) the combination of P foraging strategies (including root architecture, root hairs and root growth plasticity) is important for efficient P acquisition from a localised source of fertiliser P.     

BMI1, Stem Cell Factor Acting as Novel Serum-biomarker for Caucasian and African-American Prostate Cancer

Background

Lack of reliable predictive biomarkers is a stumbling block in the management of prostate cancer (CaP). Prostate-specific antigen (PSA) widely used in clinics has several caveats as a CaP biomarker. African-American CaP patients have poor prognosis than Caucasians, and notably the serum-PSA does not perform well in this group. Further, some men with low serum-PSA remain unnoticed for CaP until they develop disease. Thus, there is a need to identify a reliable diagnostic and predictive biomarker of CaP. Here, we show that BMI1 stem-cell protein is secretory and could be explored for biomarker use in CaP patients.

Methodology/Principal Findings

Semi-quantitative analysis of BMI1 was performed in prostatic tissues of TRAMP (autochthonous transgenic mouse model), human CaP patients, and in cell-based models representing normal and different CaP phenotypes in African-American and Caucasian men, by employing immunohistochemistry, immunoblotting and Slot-blotting. Quantitative analysis of BMI1 and PSA were performed in blood and culture-media of siRNA-transfected and non-transfected cells by employing ELISA. BMI1 protein is (i) secreted by CaP cells, (ii) increased in the apical region of epithelial cells and stromal region in prostatic tumors, and (iii) detected in human blood. BMI1 is detectable in blood of CaP patients in an order of increasing tumor stage, exhibit a positive correlation with serum-PSA and importantly is detectable in patients which exhibit low serum-PSA. The clinical significance of BMI1 as a biomarker could be ascertained from observation that CaP cells secrete this protein in higher levels than cells representative of benign prostatic hyperplasia (BPH).

Conclusions/Significance

BMI1 could be developed as a dual bio-marker (serum and biopsy) for the diagnosis and prognosis of CaP in Caucasian and African-American men. Though compelling these data warrant further investigation in a cohort of African-American patients.     

Left Atrial Structure and Function in Heart Failure with Preserved Ejection Fraction: A RELAX Substudy

Given the emerging recognition of left atrial structure and function as an important marker of disease in heart failure with preserved ejection fraction (HF-pEF), we investigated the association between left atrial volume and function with markers of disease severity and cardiac structure in HF-pEF. We studied 100 patients enrolled in the PhosphdiesteRasE-5 Inhibition to Improve CLinical Status and EXercise Capacity in Diastolic Heart Failure (RELAX) trial who underwent cardiac magnetic resonance (CMR), cardiopulmonary exercise testing, and blood collection before randomization. Maximal left atrial volume index (LAVi; N = 100), left atrial emptying fraction (LAEF; N = 99; including passive and active components (LAEF_P, LAEF_A; N = 80, 79, respectively) were quantified by CMR. After adjustment for multiple testing, maximal LAVi was only associated with age (ρ = 0.39), transmitral filling patterns (medial E/e’ ρ = 0.43), and N-terminal pro-BNP (NT-proBNP; ρ = 0.65; all p<0.05). Lower LAEF was associated with older age, higher transmitral E/A ratio and higher NT-proBNP. Peak VO₂ and V_E/VCO₂ slope were not associated with left atrial structure or function. After adjustment for age, sex, transmitral E/A ratio, CMR LV mass, LV ejection fraction, and creatinine clearance, NT-proBNP remained associated with maximal LAVi (β = 0.028, p = 0.0007) and total LAEF (β = -0.033, p = 0.001). Passive and active LAEF were most strongly associated with age and NT-proBNP, but not gas exchange or other markers of ventricular structure or filling properties. Left atrial volume and emptying function are associated most strongly with NT-proBNP and diastolic filling properties, but not significantly with gas exchange, in HFpEF. Further research to explore the relevance of left atrial structure and function in HF-pEF is warranted.