Changes in the Chlorophyll Content and Cytokinin Levels in the Top Three Leaves of New Plant Type Rice During Grain Filling

This paper reports the ways that the differences in leaf senescence are related to grain filling, grain yield, and the dynamics of cytokinins (CKs) in the top three leaves of four field-grown new plant type (NPT) rice, a tropical japonica developed at the International Rice Research Institute, Philippines, to increase the yield potential of rice. The chlorophyll content in leaves decreased from flowering to maturity in all the NPT lines, whereas the grain filling percentage was higher in the fast-senescing NPT line than in slow-senescing NPT line. Grain yield was positively correlated with senescence in the flag leaf. Rapid changes in the CK levels were recorded in the leaves of the fast-senescing line, whereas the CK levels were relatively stable in leaves of the slow-senescing line, suggesting that the dynamics of CKs in the fast-senescing line are vital for fast senescence. There were no significant changes in bioactive CKs, CK O-glucosides (storage CKs), and cis-zeatin derivatives in different leaves of the slow-senescing NPT line between 0 and 3 weeks after flowering, suggesting that the content of these CKs is relatively stable during grain filling. A progressive increase in levels of bioactive CKs was positively correlated with gradual accumulation of CK N-glucosides (inactive CKs) in the top three leaves of the slow-senescing NPT line, whereas the decrease of bioactive CKs in the flag leaf of the fast-senescing line was accompanied by accumulation of CK O-glucosides. These results suggest that there is a higher rate of biosynthesis and/or import of bioactive CKs as well as their turnover which may favor delay of leaf senescence in the slow-senescing NPT line.     

Chromosome-mediated iron uptake system in pathogenic strains of Vibrio anguillarum.

We describe in this work a new iron uptake system encoded by chromosomal genes in pathogenic strains of Vibrio anguillarum. This iron uptake system differs from the plasmid-encoded anguibactin-mediated system present in certain strains of V. anguillarum in several properties. The siderophore anguibactin is not utilized as an external siderophore, and although characteristic outer membrane proteins are synthesized under iron-limiting conditions, these are not related to the plasmid-mediated outer membrane protein OM2 associated with ferric anguibactin transport. Furthermore, the siderophore produced by the plasmidless strains may be functionally related to enterobactin as demonstrated by bioassays with enterobactin-deficient mutants, although its behavior under various chemical treatments suggested major differences from that siderophore. Hybridization experiments suggested that the V. anguillarum chromosome-mediated iron uptake system is unrelated genetically to either the anguibactin or enterobactin-associated iron assimilation systems.     

Phylogenetic relationships among the baleen whales based on maternally and paternally inherited characters

Phylogenetic relationships in the Cetacean suborder Mysticeti (baleen whales) have recently been the focus of increased attention. Here, we examine the evolutionary history of this group by comparing genealogies derived from Y chromosome and mitochondrial DNA sequences. We generated topologies based on paternally and maternally inherited characters for males from nine baleen whale species, including representatives of three families (Balaenidae, Eschrichtiidae, and Balaenopteridae) and four genera (Balaena, Eschrichtius, Balaenoptera, and Megaptera). Divergence among species was fifteen times greater for mtDNA than for Y-specific DNA. Both mtDNA and yDNA topologies revealed the family Balaenopteridae to be paraphyletic, but this relationship was neither strongly supported nor consistent across phylogenetic analysis methodologies. Humpback and fin whales, representing different genera, were reciprocally monophyletic sister species according to mtDNA. Although the monophyly of fin whales decayed for yDNA, a close relationship between fin and humpback whales was retained in yDNA trees. The paraphyly of fin whales and the long branch leading to humpback whales for the yDNA marker may suggest life history differences between these species. Specifically, male humpback whales showed higher than average divergence from other baleen whales at yDNA, although not at mtDNA, suggesting a potential for smaller effective population sizes among male humpbacks on an evolutionary timescale. The observation that those species that have been found to hybridize in nature (blue/fin and blue/humpback) do not reveal evidence for paraphyly for either maternal or paternal markers suggests that introgressive hybridization has not historically been extensive and thus may not represent a substantial source of phylogenetic error for Mysticeti.     

Effect of unilateral nephrectomy on renal function of diabetic rats

Glomerular alterations of experimental diabetes mellitus are observed in animals submitted to a reduction in renal mass, suggesting that some mechanisms responsible for the progression of renal disease are common. The aim of this study was to investigate the effect of nephrectomy on the renal function and morphology of diabetic rats. Male Wistar rats were divided into 4 groups: control (C), n=8; diabetic (DM), n=8; non-diabetic nephrectomized (Nx), n=8; (DMNx), n=9. DM was induced by streptozotocin (65 mg/Kg), and animals were treated with insulin. After 12 weeks, the glomerular filtration rate (GFR), renal plasma flow (RPF) and mean arterial pressure (MAP) were evaluated in unanaesthetized animals. Glomerular volume (GV), glomerular sclerosis index (GSI), mesangial volume density (Vvmes) and glomerular capillary surface density (Svcap) were also evaluated. Results show that kidney weight increased in Nx groups, being higher in DMNx. GFR was higher in Nx groups as was RPF, being higher in DMNx. RVR was lower in Nx groups, especially in DMNx. MAP was not different among the groups. RPF and GFR showed a high correlation for the DMNx group (r=0.95, p=0.02). The DMNx group showed a correlation between RVR and GFR (r=-0.96, p=0.005). The GV increased in Nx groups, and the GSI was higher in DMNx. Vvmes and Svcap increased in DMNx group. In summary, Nx groups developed similar degrees of glomerular hypertrophy, but only DMNx showed an increased value for GSI. The present data suggest that the acceleration of glomerular lesions in DMNx animals was more closely associated to hemodynamic adaptations than to glomerular hypertrophy.     

Molecular modelling of the TSR domain of R-spondin 4

R-spondin 4 is a secreted protein mainly associated with embryonic nail development. R-spondins have been recently identified as heparin-binding proteins with high affinity. Proteoglycan binding has been associated with both the TSR and the C terminal basic amino acid rich domains. In this paper, molecular modelling techniques were used to construct the model of R-spondin 4 TSR domain based on the structure of the F-spondin TSR domain 4 (30-40¢ sequence identity). Beside a positively charged surface in the TSR domain, presence of the basic amino acid rich domain which could forms a continuous heparin binding surface may explain the high affinity of R-spondins for heparin. Our results provide a framework for understanding the possible regulatory role of heparin in R-spondins signalling.     

Length–weight relationships for 35 fish species of the Atlantic Forest,SP/RJ—Brazil

Length–weight relationships (LWRs) for 35 freshwater fish species from the SP/RJ coastal basin in Brazil are presented in this paper. Fishes were captured between 2011 and 2015 on an irregular basis using electrofishing, sieves, trawl nets, cast nets and fish‐traps. In this study new LWRs are reported for 28 species, plus the total weight and length for 34 and nine species, respectively. The study provides new information on less‐studied species and can serve as a basis for management and conservation in this area.     

Comparison of the effects of HGF,BDNF, CT‐1, CNTF,and the branchial arches on the growth of embryonic cranial motor neurons

In the developing embryo, axon growth and guidance depend on cues that include diffusible molecules. We have shown previously that the branchial arches and hepatocyte growth factor (HGF) are growth‐promoting and chemoattractant for young embryonic cranial motor axons. HGF is produced in the branchial arches of the embryo, but a number of lines of evidence suggest that HGF is unlikely to be the only factor involved in the growth and guidance of these axons. Here we investigate whether other neurotrophic factors could be involved in the growth of young cranial motor neurons in explant cultures. We find that brain‐derived neurotrophic factor (BDNF), ciliary neurotrophic factor (CNTF) and cardiotrophin‐1 (CT‐1) all promote the outgrowth of embryonic cranial motor neurons, while glial cell line‐derived neurotrophic factor (GDNF) and neurotrophin‐3 (NT‐3) fail to affect outgrowth. We next examined whether HGF and the branchial arches had similar effects on motor neuron subpopulations at different axial levels. Our results show that HGF acts as a generalized rather than a specific neurotrophic factor and guidance cue for cranial motor neurons. Although the branchial arches also had general growth‐promoting effects on all motor neuron subpopulations, they chemoattracted different axial levels differentially, with motor neurons from the caudal hindbrain showing the most striking response. © 2002 Wiley Periodicals, Inc. J Neurobiol 51: 101–114, 2002     

Influence of maize root mucilage on soil aggregate stability

This study was undertaken to determine the effects of root exudates on soil aggregate stability. Root mucilage was collected from two-month old maize plants (Zea mays L.) Mucilage and glucose solutions were added at a rate of 2.45 g C kg⁻¹ dry soil to silty clay and silt loam soils. Amended soils, placed in serum flasks, were incubated for 42 d with a drying-wetting cycle after 21 d. Evolved CO₂ was measured periodically as well as the water-stable aggregates and soluble sugar and polysaccharide content of the soil. In mucilage-amended soils CO₂ evolution started with a lag phase of 2–3 days, which was not observed in glucose-amended soils. There was then a sharp increase in evolved CO₂ up to day 7. During the second incubation period there were only small differences in evolved C between treatments. Incorporation of mucilage in both soils resulted in a spectacular and immediate increase in soil aggregate stability. Thereafter, the percent of water-stable aggregates quickly decreased parallel to microbial degradation. On completion of the incubation, aggregate stability in the silty clay soil was still significantly higher in the presence of mucilage than in the control. This work supports the assumption that freshly released mucilage is able to stick very rapidly to soil particles and may protect the newly formed aggregates against water destruction. On the silty clay, microbial activity contributes to a stabilization of these established organo-mineral bounds.     

Synthesize of β‐cyclodextrin functionalized dendritic fibrous nanosilica and its application for the removal of organic dye (malachite green)

Dye removal from industrial waste water has become an important issue. The highvisibility, undesirability and recalcitrance are the significant environmental problemfor the dyes. In the present work,β‐cyclodextrin functionalized KCC‐1 (KCC‐1‐NH‐β‐CD)was synthesized and utilized to the removal of hazardous malachite green. In order to study the morphology of the synthesized nano adsorbent, Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) were obtained from the surface of the sample. Additionally, the functionalization of KCC‐1 with β‐cyclodextrin was confirmed with Furrier Transform Infrared spectroscopy (FTIR). The textural property of KCC‐1 was verified using nitrogen adsorption/ desorption analysis (BET equation). UV‐Vis spectroscopy utilized for the investigation of malachite green by KCC‐1‐NH‐β‐CD. Specific surface area of the adsorbent was calculated to be 140 m²/g and it can be stated that the synthesized nano adsorbent has high removal efficiency. It should be noted that the adsorption capacity of the employed nano adsorbent was more than 95%, which could be attributed to high porosity of β‐cyclodextrin functionalized KCC‐1.     

Molecular evidence and clinical importance of β‐arrestins expression in patients with acromegaly

β‐arrestins seem to have a role in endocytosis and desensitization of somatostatin receptor subtype 2 (sst2) and could be associated with the responsiveness to somatostatin receptor ligands (SRL) in patients with acromegaly. To investigate the in vivo correlation between β‐arrestins 1 and 2 with sst2, sst5 and dopamine receptor subtype 2 (D2) expressions, and the association of β‐arrestins with response to first‐generation SRL and invasiveness in somatotropinomas. β‐arrestins 1 and 2, sst2, sst5 and D2 mRNA expressions were evaluated by quantitative real‐time RT‐PCR on tumoral tissue of 96 patients. Moreover, sst2 and sst5 protein expressions were also evaluated in 40 somatotropinomas by immunohistochemistry. Response to SRL, defined as GH <1 μg/l and normal IGF‐I levels, was assessed in 40 patients. The Knosp‐Steiner criteria were used to define invasiveness. Median β‐arrestin 1, β‐arrestin 2, sst2, sst5 and D2 mRNA copy numbers were 478; 9375; 731; 156 ; and 3989, respectively. There was a positive correlation between β‐arrestins 1 and 2 (R = 0.444, P < 0.001). However, no correlation between β‐arrestins and sst2, sst5 (mRNA and protein levels) or D2 was found. No association was found between β‐arrestins expression and SRL responsiveness or tumour invasiveness. Although previous data suggest a putative correlation between β‐arrestins and sst2, our data clearly indicated that no association existed between β‐arrestins and sst2, sst5 or D2 expression, nor with response to SRL or tumour invasiveness. Therefore, further studies are required to clarify whether β‐arrestins have a role in the response to treatment with SRL in acromegaly.