Synthesis of cubic ZnS microspheres exhibiting broad visible emission for bioimaging applications

Biocompatible ZnS microspheres with an average diameter of 3.85 µm were grown by solvo‐hydrothermal (S‐H) method using water–acetonitrile–ethylenediamine (EDA) solution combination. ZnS microspheres were characterized by X‐ray diffraction (XRD), scanning electron microscopy (SEM), high‐resolution transmission electron microscopy (HRTEM), Fourier transform (FT)‐Raman spectroscopy and Fourier transform infrared spectroscopy (FTIR) techniques. The broad photoluminescence (PL) emissions from 380–580 nm that were seen from the ZnS microspheres attributed to the increase in carrier concentration, as understood from the observed intense Raman band at 257 cm^–1. Cytotoxicity and haemocompatibility investigations of these ZnS microspheres revealed its biocompatibility. ZnS microspheres, along with biological cell lines, were giving visible light emission and could be used for bioimaging applications. Copyright © 2015 John Wiley & Sons, Ltd.     

蚕豆根瘤菌接种效应研究

为发掘和利用青海冷凉地区蚕豆优良的根瘤菌种质资源,确定根瘤菌的接种效应。将分离、纯化、分子鉴定的16株蚕豆根瘤菌通过盆栽回接试验的方法进行筛选。结果表明,筛选出6株根瘤菌,它们与青海13号蚕豆共生匹配效果较好,共生固氮能力强,促进蚕豆生长效果明显。     

水稻氮素营养高光谱遥感诊断模型

对水稻氮素含量与原始光谱反射率、一阶微分光谱以及高光谱特征参数间的相关性进行了分析,并构建和验证了以遥感参数为自变量的水稻氮素营养诊断模型.结果表明：氮素含量在水稻各器官中总的变化趋势为茎<鞘<穗<叶;各器官在可见光波段的光谱反射能力为叶<穗<鞘<茎,在近红外波段则与此相反.以波长796.7 nm处的光谱反射率和738.4 nm处的一阶微分光谱反射率为自变量的线性模型和指数模型的决定系数（R²）分别为0.7996和0.8606,二者均能较好地诊断水稻氮素营养,但最适合诊断水稻氮素含量的拟合模型是以植被指数的归一化变量（SD_r-SD_b）/（SD_r+SD_b）为自变量构建的水稻氮素营养高光谱遥感诊断模型［y=365871+639323（SD_r-SD_b）/（SD_r+SD_b）,R₂＝0.8755,RMSE＝0.2372,相对误差＝11.36％］,该模型可定量诊断水稻氮素营养.     

Efficacy of different indices derived from spectral reflectance of wheat for nitrogen stress detection

Abstract

The productivity of cereal crops is mainly related to their nitrogen status. It is hypothesized that the spectral reflectance data could be used to predict wheat nitrogen status with spectral indices and that their performance depends on the nature of the interaction of the solar radiation with the crop canopy. A wheat crop was raised with 12 levels of nitrogen treatments: 0, 15, 30, 40, 50, 60, 70, 80, 90, 100, 110, and 120 kg ha^?1, with uniform phosphorous and potassium nutrition and uniform water and management practice. The spectral reflectance measurements of the crop canopy were taken at 5 nm intervals, throughout the crop growth period. Different spectral indices, both broadband (ratio as well as orthogonal) and hyperspectral indices were computed throughout the growing season. Canopy Colour Difference (ΔE), an index developed from the entire visible region and hence broader than the spectral indices developed hitherto, was also estimated from the reflectance data. Simple linear relationships developed between spectral indices versus applied nitrogen levels as well as the plant nitrogen content revealed that the hyperspectral indices are less sensitive in comparison to broadband indices. The result was reinforced by a higher correlation between the colour difference, NDVI and Greenness Index with plant nitrogen level/content, as opposed to hyperspectral indices.     

Broad‐substrate screen as a tool to identify substrates for bacterial Gcn5‐related N‐acetyltransferases with unknown substrate specificity

Due to a combination of efforts from individual laboratories and structural genomics centers, there has been a surge in the number of members of the Gcn5‐related acetyltransferasesuperfamily that have been structurally determined within the past decade. Although the number of three‐dimensional structures is increasing steadily, we know little about the individual functions of these enzymes. Part of the difficulty in assigning functions for members of this superfamily is the lack of information regarding how substrates bind to the active site of the protein. The majority of the structures do not show ligand bound in the active site, and since the substrate‐binding domain is not strictly conserved, it is difficult to predict the function based on structure alone. Additionally, the enzymes are capable of acetylating a wide variety of metabolites and many may exhibit promiscuity regarding their ability to acetylate multiple classes of substrates, possibly having multiple functions for the same enzyme. Herein, we present an approach to identify potential substrates for previously uncharacterized members of the Gcn5‐related acetyltransferase superfamily using a variety of metabolites including polyamines, amino acids, antibiotics, peptides, vitamins, catecholamines, and other metabolites. We have identified potential substrates for eight bacterial enzymes of this superfamily. This information will be used to further structurally and functionally characterize them.     

Multiple antigen peptide mimetics containing gp41 membrane‐proximal external region elicit broad neutralizing antibodies against human immunodeficiency virus type 1 in guinea pigs

Eliciting a broadly neutralizing antibody response against the HIV‐1 membrane‐proximal external region (MPER) mimicking the activity of 4E10 and 2F5 monoclonal antibodies remains a major challenge. In this study, two novel tetra‐branched peptide immunogens, 4E10‐ and 2F5‐MAP4, were designed and synthesized using a MAP system. Guinea pigs were immunized with either of these two synthetic immunogens emulsified in an oil‐phase adjuvant at 3‐week intervals. After four immunizations, epitope‐specific antibody responses were induced successfully, and moderate neutralizing activities against tier 1 (clades B, BC, AE) and tier 2 (clade C) HIV‐1 pseudoviruses were detectable in unfractionated sera and purified IgGs. The synthetic gp41 membrane‐proximal external region peptide mimetics, 4E10‐ and 2F5‐MAP4, assisted by an appropriate adjuvant, are promising prophylactic vaccine candidates potentially capable of eliciting broadly neutralizing antibody responses against HIV‐1. Copyright © 2013 European Peptide Society and John Wiley & Sons, Ltd.     

Rubinstein-Taybi syndrome: Clinical profile of 11 patients and review of literature

BACKGROUND:

Rubinstein-Taybi syndrome (RSTS) is a rare congenital neurodevelopmental disorder, characterized by postnatal growth deficiency, typical dysmorphic features, broad thumbs and toes, and mental retardation. Very few cases are reported in literature from developing countries. Diagnosis is often delayed due to non-familiarity with the characteristic features of this syndrome.

AIMS:

To report 11 cases of RSTS and to review the current literature.

SETTINGS AND DESIGN:

Retrospective study conducted in genetic and metabolic unit of a tertiary care teaching hospital in north India over a period of 3½ years.

MATERIALS AND METHODS:

11 patients with diagnosis of RSTS were identified, and their case sheets were reviewed.

RESULTS:

Developmental delay was presenting complaint in 10 patients, and seizure in 1 case. 7 patients had microcephaly (head circumference below −3 SD), and a prominent beaked nose was seen in 9 patients. The intelligence quotient (IQ) varied from 22-62 in 7 patients who had mental retardation. The most notable features in hands were broadness, shortening, and flattening of the distal phalanx of thumbs or great toes. Additionally, we also noted webbing of neck, microphthalmia, and pachygyria (on MRI brain) in 1 patient each.

CONCLUSIONS:

The diagnosis of RSTS is primarily clinical and based on characteristic phenotype that is often combined with a variety of somatic anomalies. An early diagnosis facilitates appropriate genetic counseling and in planning the management.     

Phenotypic variability and heritability of the cephalic region of Caiman latirostris

The study of the cephalic shape of crocodilian is relevant in the fields of ecology, systematics, evolution, and conservation. Therefore, the integration of geometric analysis within quantitative genetics allows the evaluation of the inheritable shape components. In this study, the dorsal cephalic region of 210 Caiman latirostris hatchlings was analyzed from seven populations in Santa Fe, Argentina, to detect intra‐, and inter‐population phenotypic variability, and to determine the heritability of biological shape and size, using newly available geometric morphometric tools. The principal component analysis showed two configurations of cephalic shape that could be related to sexual dimorphism. In the canonical variate analysis, Procrustes distances between groups indicated that there are differences in shape among populations. Furthermore, the method of partial least squares indicated a covariation between cephalic shape and environmental variables. Regarding to CS of the skull we found significant differences among populations, moreover the partial least squares was also significant. Estimates of the heritability of shape and size were high, indicating that the components of these features are susceptible to the selection. J. Morphol. 277:370–378, 2016. © 2015 Wiley Periodicals, Inc.     

Mycotoxin production on different cultivars and lines of broad bean (Vicia faba L.) seeds in Egypt

One hundred different cultivars and lines of broad bean (Vicia faba L.) seed samples were inoculated with Aspergillus flavus Link (CMI 102135) to determine varietal differences which may support or resist aflatoxin production. Thin-layer chromatographic analysis of the chloroform extracts of the different seed samples revealed that 11 cultivars/lines were highly resistant to seed invasion and aflatoxin production while 9 cultivars/lines showed partial resistance. The remaining 80 samples were susceptible to the establishment of A. flavus and aflatoxin accumulation. All the resistant cultivars/lines seed samples were inoculated also with three local isolates of fungi namely; Stachybotrys chartarum (Ehrenb. ex Link) Hughes, Aspergillus ochraceus Wilhelm, and Fusarium oxysporum Schlecht. The resistant seed samples were also resistant for colonization with these fungi and mycotoxin formation.     

Oxidative stress in herbicide-treated broad bean and maize plants

Treatments of broad bean and maize seedlings with fluometuron, atrazine or rimsulfuron affected some parameters of oxidative stress. Fluometuron significantly reduced activity of Hill reaction (PSII), chlorophyll a+b contents and activity of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco, EC 4.1.1.39) in leaves of both species and significantly increased contents of H₂O₂, lipid peroxides and carbonyl groups during the whole experiment. There were, moreover, significant inhibitions in activities of superoxide dismutase (SOD; E.C. 1.15.1.1), catalase (CAT; E.C. 1.11.1.6), ascorbate peroxidase (APX; E.C. 1.11.1.11) and guaiacol peroxidase (GPX; E.C. 1.11.1.7). Response to atrazine was, to some extent, similar to fluometuron throughout the entire experiment in broad bean and up mostly to the 12^th day of the experiment in maize. The herbicide effect was more pronounced in broad bean than maize. These results point to indicate an occurrence of oxidative stress in both species by fluometuron and only in broad bean by atrazine. The increase in H₂O₂ content accompanied with drop in activities of SOD, CAT and peroxidases indicates a decline in its detoxification rather than increase in its synthesis. On the contrary, rimsulfuron seemed to have no effect on most of the tested parameters although there were transient significant increases in H₂O₂, lipid peroxides and carbonyl groups as well as activities of SOD, CAT, APX and GPX. These findings, based on the recovery in oxidative stress, indicate that fluometuron is involved in oxidative stress generation in both species but atrazine only in broad bean while rismulfuron is not in both species.