Influence of hypercapnic vasodilation on cerebrovascular autoregulation and pial arteriolar bed resistance in piglets.

Changes in both pial arteriolar resistance (PAR) and simulated arterial-arteriolar bed resistance (SimR) of a physiologically based biomechanical model of cerebrovascular pressure transmission, the dynamic relationship between arterial blood pressure and intracranial pressure, are used to test the hypothesis that hypercapnia disrupts autoregulatory reactivity. To evaluate pressure reactivity, vasopressin-induced acute hypertension was administered to normocapnic and hypercapnic (N = 12) piglets equipped with closed cranial windows. Pial arteriolar diameters were used to compute arteriolar resistance. Percent change of PAR (%DeltaPAR) and percent change of SimR (%DeltaSimR) in response to vasopressin-induced acute hypertension were computed and compared. Hypercapnia decreased cerebrovascular resistance. Indicative of active autoregulatory reactivity, vasopressin-induced hypertensive challenge resulted in an increase of both %DeltaPAR and %DeltaSimR for all normocapnic piglets. The hypercapnic piglets formed two statistically distinct populations. One-half of the hypercapnic piglets demonstrated a measured decrease of both %DeltaPAR and %DeltaSimR to pressure challenge, indicative of being pressure passive, whereas the other one-half demonstrated an increase in these percentages, indicative of active autoregulation. No other differences in measured variables were detectable between regulating and pressure-passive piglets. Changes in resistance calculated from using the model mirrored those calculated from arteriolar diameter measurements. In conclusion, vasodilation induced by hypercapnia has the potential to disrupt autoregulatory reactivity. Our physiologically based biomechanical model of cerebrovascular pressure transmission accurately estimates the changes in arteriolar resistance during conditions of active and passive cerebrovascular reactivity.     

Biosynthesis and characterization of silver nanoparticles from symbiotic bacteria Xenorhabdus nematophila and testing its insecticidal efficacy on Spodoptera litura larvae

BioMetals - Spodoptera litura, one of the polyphagous pests, causes huge economical lose and use of chemical pesticide causes impact to the environmental. The present study deals with the use of...     

Intense Floral Scent Emission in Polianthes tuberosa L. (Tuberose) Variants Sprouted from γ-Irradiated Tubers

Journal of Plant Growth Regulation - Tuberose (Polianthes tuberosa L.) is a tuberous, perennial, night-blooming ornamental plant which is commercially cultivated in different parts of India. In the...     

Structural basis for the cooperative DNA recognition by Smad4 MH1 dimers

Smad proteins form multimeric complexes consisting of the 'common partner' Smad4 and receptor regulated R-Smads on clustered DNA binding sites. Deciphering how pathway specific Smad complexes multimerize on DNA to regulate gene expression is critical for a better understanding of the cis-regulatory logic of TGF-β and BMP signaling. To this end, we solved the crystal structure of the dimeric Smad4 MH1 domain bound to a palindromic Smad binding element. Surprisingly, the Smad4 MH1 forms a constitutive dimer on the SBE DNA without exhibiting any direct protein-protein interactions suggesting a DNA mediated indirect readout mechanism. However, the R-Smads Smad1, Smad2 and Smad3 homodimerize with substantially decreased efficiency despite pronounced structural similarities to Smad4. Therefore, intricate variations in the DNA structure induced by different Smads and/or variant energetic profiles likely contribute to their propensity to dimerize on DNA. Indeed, competitive binding assays revealed that the Smad4/R-Smad heterodimers predominate under equilibrium conditions while R-Smad homodimers are least favored. Together, we present the structural basis for DNA recognition by Smad4 and demonstrate that Smad4 constitutively homo- and heterodimerizes on DNA in contrast to its R-Smad partner proteins by a mechanism independent of direct protein contacts.     

MEDDB: a medicinal plant database developed with the information gathered from tribal people in and around Madurai, Tamil Nadu

Tribal peoples are endowed with enriched traditional wisdom to use available nature resources around them. They are well versed in the usage of plant for treating various diseases. They have used powder or extract or paste form of the plant parts such as root, shoot, whole plant, fruits and leaves etc. The recipe known by the tribal people was passed on only to their family members and community through mouth to mouth practice. Hence, the knowledge is confined to particular people alone. It is always expedient to store information in the database, so that it will be accessible by everyone from everywhere. To achieve this, MEDDB has been developed, which stores the details of 110 plant species that are commonly used by tribes for fever, asthma, cold, cough, diabetes, diarrhea, dysentery, eye infections, stomach ache, wounds and snake bite. The details of each plant were collected from the literature and through web search to give comprehensive and exhaustive information. Each plant entry is compiled under the subheadings viz., common name, classification, physical characteristics, medicinal uses, active constituents, and references.     

The Prolyl Isomerase Pin1 Targets Stem-Loop Binding Protein (SLBP) To Dissociate the SLBP-Histone mRNA Complex Linking Histone mRNA Decay with SLBP Ubiquitination

Histone mRNAs are rapidly degraded at the end of S phase, and a 26-nucleotide stem-loop in the 3′ untranslated region is a key determinant of histone mRNA stability. This sequence is the binding site for stem-loop binding protein (SLBP), which helps to recruit components of the RNA degradation machinery to the histone mRNA 3′ end. SLBP is the only protein whose expression is cell cycle regulated during S phase and whose degradation is temporally correlated with histone mRNA degradation. Here we report that chemical inhibition of the prolyl isomerase Pin1 or downregulation of Pin1 by small interfering RNA (siRNA) increases the mRNA stability of all five core histone mRNAs and the stability of SLBP. Pin1 regulates SLBP polyubiquitination via the Ser20/Ser23 phosphodegron in the N terminus. siRNA knockdown of Pin1 results in accumulation of SLBP in the nucleus. We show that Pin1 can act along with protein phosphatase 2A (PP2A) in vitro to dephosphorylate a phosphothreonine in a conserved TPNK sequence in the SLBP RNA binding domain, thereby dissociating SLBP from the histone mRNA hairpin. Our data suggest that Pin1 and PP2A act to coordinate the degradation of SLBP by the ubiquitin proteasome system and the exosome-mediated degradation of the histone mRNA by regulating complex dissociation.     

Molecular detection of Colletotrichum falcatum causing red rot disease of sugarcane (Saccharum officinarum) using a SCAR marker

Red rot disease of sugarcane caused by Colletotrichum falcatum is one of the most destructive diseases of sugarcane (Saccharum officinarum) worldwide. The pathogen spreads primarily through infected sugarcane setts and hence the use of disease‐free planting materials is essential for preventing disease development in the field. In the present study a polymerase chain reaction (PCR) assay was developed for accurate and sensitive detection of C. falcatum in planting materials. Randomly amplified polymorphic DNA (RAPD) analysis identified a 566 bp PCR fragment that was specific to C. falcatum. The DNA sequence of this fragment was determined and used to design oligonucleotides amplifying a 442 bp sequence characterised amplified region (SCAR). The specificity of the SCAR primers was evaluated using purified DNA from C. falcatum and other Colletotrichum spp. as templates in PCR. The results indicated that the SCAR primers were highly specific to C. falcatum since the 442 bp fragment was amplified only from DNA of isolates and races of C. falcatum but not from any other Colletotrichum spp. tested. The detection sensitivity of C. falcatum was 0.1 ng for genomic DNA of C. falcatum and 5 ng for DNA extracted from infected sugarcane tissue. This new PCR‐based assay is a convenient tool for detection of this important pathogen in seed canes to ensure production of sugarcane.     

Utilization of Industrial Waste for the Production of Bio-Preservative from <Emphasis Type="Italic">Bacillus licheniformis</Emphasis> Me1 and Its Application in Milk and Milk-Based Food Products

The bio-preservative efficacy of a partially purified antibacterial peptide (ppABP) produced by Bacillus licheniformis Me1 in an economical medium developed using agro-industry waste was evaluated by direct application in milk and milk-based food products. The addition of ppABP in milk samples stored at 4 ± 2 °C and 28 ± 2 °C resulted in the growth inhibition of pathogens Listeria monocytogenes Scott A, Micrococcus luteus ATCC 9341, and Staphylococcus aureus FRI 722. The shelf life of milk samples with added ppABP increased to 4 days at 28 ± 2 °C, whereas curdling and off-odor were noticed in samples without ppABP. Furthermore, the milk samples with ppABP were sensorily acceptable. Antilisterial effect was also observed in cheese and paneer samples treated with ppABP. These results clearly indicate that the ppABP of B. licheniformis Me1 can be utilized as a bio-preservative to control the growth of spoilage and pathogenic bacteria, thereby reducing the risk of food-borne diseases.     

Spatial Variability of Biofuel Production Potential and Hydrologic Fluxes of Land Use Change from Cotton (<Emphasis Type="Italic">Gossypium hirsutum</Emphasis> L.) to Alamo Switchgrass (<Emphasis Type="Italic">Panicum virgatum</Emphasis> L.) in the Texas High Plains

Bioenergy crop production has the potential to protect marginal crop lands that generate high surface runoff and produce poor crop yields. Long-term evaluation of the impacts of such land use change on hydrologic fluxes and biofuel production potential is necessary before adopting such strategies on a large scale. In this study, the hydrologic impacts of replacing cotton (Gossypium hirsutum L.) on marginal lands in an intensive agricultural watershed in the Texas High Plains with Alamo switchgrass (Panicum virgatum L.) as a bioenergy crop were evaluated using the Agricultural Policy/Environmental eXtender (APEX) model. The surface runoff to cotton yield ratio was used as a criterion to identify marginal cotton subareas (homogenous spatial units delineated by APEX) in the study watershed, and three replacement scenarios (low (9 %), medium (33 %), and high (57 %) extents of cotton acreage replaced by switchgrass) were implemented in the scenario analysis. The average (1994–2009) annual surface runoff decreased by about 84 and 66 %, and the percolation increased by 106 and 57 % in the irrigated and dryland subareas, respectively, when cotton was replaced by switchgrass under the high replacement scenario. Spatial analysis showed that switchgrass was a feasible bioenergy crop for replacing cotton, especially in the western part of the study watershed, due to its higher water use efficiency and better water conservation effects compared to cotton. It is estimated that 193 and 381 million liters of ethanol could be produced from the dryland and irrigated subareas of the study watershed, respectively, under the high replacement scenario.