A novel, brain-specific mouse drebrin: cDNA cloning, chromosomal mapping, genomic structure, expression, and functional characterization

Drebrin A, a major neuronal actin-binding protein, regulates the dendritic spine shapes of neurons. Here, we have cloned and characterized a novel mouse cDNA clone encoding a truncated form of drebrin A, named s-drebrin A. Analysis of the genomic organization of the mouse drebrin gene (Dbn1), which mapped to the central portion of chromosome 13, revealed that isoforms including s-drebrin A are generated by alternative splicing from a single drebrin gene. The s-drebrin A mRNA was expressed in the brain, but not in non-neuronal tissues. The s-drebrin A expression was barely detected in the embryonic brain, but was upregulated during postnatal development of the brain. Overexpression of GFP-tagged s-drebrin A in fibroblasts showed it to be associated with actin filaments and with changes in actin cytoskeleton organization. These findings suggest that s-drebrin A has a role in spine morphogenesis, possibly by competing the actin-binding activity with drebrin A.     

Revisione delle specie: Actinomyces albus,A. chromogenus,A. odorifer,A. thermophylus,A. viridis,A. viridochromogenes,A. hominis,A. innominatus

Riassunto Lo studio comprende una revisione critico-sperimentale della specie Actinomyces albus, della quale vengono considerati come sinonimi circa 30 nomi speeifici, fra i quale A. chromogenus, A. odorifer, A. thermophylus p.p.; della specie é data una diagnosi ed una particolareggiata descrizione.Sono inoltre studiate le specie A. viridis, (= A. viridochromogenus) e A. innominatus, n. nomen. Quest'ultima é preceduta da una breve discussione sulla specie A. homini.

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Summary Twenty-six strains of Actinomyces albus are studied redescribed from morphological, cultural and biochemical standpoints. Many biological activities of A. chromogenus, A. odorifer and A. thermophilus are in common with other species of the same genus, so that they may be considered for sub-specific, (not specific) differentiation. A discussion on A. farcinicus, A. albidoflavus and A. aureus has been originated from mislabeling as A. albus; the group including the two last named species (flavus group) must be revised. A few strains classified A. farcinicus are in no doubt true A. albus, but this real specific entity remains to be revised from Nocard's strain. A. viridis, for the first time described by Lombardo-Pellegrino, has been redescribed three times as a new species under the same binomial, and the fourth as A. viridochromogenes. A. hominis Bostroem is an uncorrect determination for the species originally described by Waksmann and Curtiss, and it is renamed A. innominatus, the binomial A. (Streptothrix) hominis Auct. being a nomen ambiguum. In conclusion, 30 bionmial are appended in sinonimy to A. albus, including Cladothrix dichotoma Macé (1888) non Cohn, G. invulnerabilis Acosta et G. Rossi, C. odorifera Rullm. Actinomyces chromogenus Gasp., A. thermophilus Auct., p.p., A. (Streptothrix) Sanninii (Cif.) Westerd., A. Almquisti Duché, A. Gougeroti Duché, and so on.

     

Frondoside A Suppressive Effects on Lung Cancer Survival,Tumor Growth,Angiogenesis, Invasion,and Metastasis

A major challenge for oncologists and pharmacologists is to develop less toxic drugs that will improve the survival of lung cancer patients. Frondoside A is a triterpenoid glycoside isolated from the sea cucumber, Cucumaria frondosa and was shown to be a highly safe compound. We investigated the impact of Frondoside A on survival, migration and invasion in vitro, and on tumor growth, metastasis and angiogenesis in vivo alone and in combination with cisplatin. Frondoside A caused concentration-dependent reduction in viability of LNM35, A549, NCI-H460-Luc2, MDA-MB-435, MCF-7, and HepG2 over 24 hours through a caspase 3/7-dependent cell death pathway. The IC50 concentrations (producing half-maximal inhibition) at 24 h were between 1.7 and 2.5 µM of Frondoside A. In addition, Frondoside A induced a time- and concentration-dependent inhibition of cell migration, invasion and angiogenesis in vitro. Frondoside A (0.01 and 1 mg/kg/day i.p. for 25 days) significantly decreased the growth, the angiogenesis and lymph node metastasis of LNM35 tumor xenografts in athymic mice, without obvious toxic side-effects. Frondoside A (0.1–0.5 µM) also significantly prevented basal and bFGF induced angiogenesis in the CAM angiogenesis assay. Moreover, Frondoside A enhanced the inhibition of lung tumor growth induced by the chemotherapeutic agent cisplatin. These findings identify Frondoside A as a promising novel therapeutic agent for lung cancer.     

ERRATUM: Beall CM,Brittenham GM,Strohl KP,Blangero J,Williams-Blangero S,Goldstein MC,Decker MJ,Vargas E,Villena M,Soria R,Alarcon AM,and Gonzales C (1998) Hemoglobin Concentration of High-altitude Tibetans and Bolivian Aymara. Am. J. Phys. Anthropol. 106:385–400.

Figures 1A and B were switched with Figures 3A and B. The Figures on pages 390 and 391 plotting hemoglobin concentration against percent of oxygen saturation of arterial hemoglobin are Figures 3A and B rather than Figures 1A and B as printed. The Figures on pages 394 and 395 plotting hemoglobin concentration against age are Figures 1A and B rather than Figures 3A and B as printed.     

Primary biliary cirrhosis,dark adaptometry,electro-oculography,and vitamin A state.

Twenty five patients with primary biliary cirrhosis were studied for vitamin A state. In nine patients found to have low circulating vitamin A concentrations no abnormality was found on electro-oculography or in dark adaptation. A positive correlation was found between retinol binding protein and vitamin A values (r = +0.88; p less than 0.001) and between serum albumin and vitamin A values (r = +0.75; p less than 0.001). A weaker and negative correlation was found between serum bilirubin (r = -0.47; p less than 0.05) and vitamin A values. Patients with primary biliary cirrhosis should not receive regular parenteral or even oral vitamin A supplementation unless dark adaptometry or electrooculography yields an abnormal result.     

Aluminium effects on growth and Al,Ca, Mg,K and P levels in triticale,wheat and rye

Summary The effects of A1 on the growth and mineral composition of different cultivars of triticale (X Triticosecale, Wittmack), wheat (Triticum aestivum L.) and rye (Secale cereale L.) growing in 1/5 strength Steinberg solutions containing 0 or 6 ppm A1 were evaluated after 32 days. Aluminum increased the concentrations of P and K in the roots and K in the tops of most of the cultivars tested. A1 tolerant triticale retained a lower concentration of Mg in the roots and tops than the A1 sensitive triticale, when subjected to A1 stress. In addition, A1 treatments resulted in smaller increases in root P for the A1 tolerant triticale than for the A1 sensitive cultivars.The concentration of root Ca and P of the A1 tolerant wheat cultivars were significantly below that of the more sensitive plants. Aluminum tolerance in rye appeared to be associated with lower Ca and higher Mg concentrations in the tops. The accumulation of P and A1 in the roots was characteristic of sensitivity in triticale, wheat and rye.     

New species of Alaus Eschscholtz, 1829 (Coleoptera: Elateridae,Agrypninae, Hemirhipini)

Four new species of Alaus Eschscholtz, 1829 are described: A. cinnamomeus n. sp., A. latlpennls n. sp., A. serlceus n. sp. and A. thoracopunctatus n. sp. Three species removed from Chalcolepldlus Eschscholtz, 1829, are transferred to this genus: A. allcll (Pjatakowa, 1941) n. comb., A. haroldl (Candèze, 1878) n.comb. and A. unlcus (Fleutiaux, 1910) n. comb. The characters of external morphology of these seven species and male and female genitalia, when available, are described and illustrated. An identification key for all species of the genus is included: A. allcll (Pjatakowa, 1941) n. comb., A. calcarlpllosus Casari, 1996, A. cinnamomeus n. sp., A. haroldl (Candèze, 1878) n. comb., A. latlpennls n. sp., A. lusclosus (Hope, 1832), A. melanops Leconte, 1863, A. myops (Fabricius, 1801), A. nobllls Sallé, 1855, A. oculatus (Linnaeus, 1758), A. patrlclus (Candèze, 1857), A. plebejus Candèze, 1874, A. serlceus n. sp., A. thoracopunctatus n. sp., A. tricolor (Olivier, 1790), A. unlcus (Fleutiaux, 1910) n. comb., A. veracruzanus Casari, 1996 and A. zunianus Casey, 1893.     

Metabolism of aflatoxin, ochratoxin, zearalenone, and three trichothecenes by intact rumen fluid, rumen protozoa, and rumen bacteria

The effect of rumen microbes on six mycotoxins (aflatoxin B1, ochratoxin A, zearalenone, T-2 toxin, diacetoxyscirpenol, and deoxynivalenol ) considered to be health risks for domestic animals was investigated. The mycotoxins were incubated with intact rumen fluid or fractions of rumen protozoa and bacteria from sheep and cattle in the presence or absence of milled feed. Rumen fluid had no effect on aflatoxin B1 and deoxynivalenol . The remaining four mycotoxins were all metabolized, and protozoa were more active than bacteria. Metabolism of ochratoxin A, zearalenone, and diacetoxyscirpenol was moderately or slightly inhibited by addition of milled feed in vitro. The capacity of rumen fluid to degrade ochratoxin A decreased after feeding, but this activity was gradually restored by the next feeding time. Ochratoxin A was cleaved to ochratoxin alpha and phenylalanine; zearalenone was reduced to alpha-zearalenol and to a lesser degree to beta-zearalenol; diacetoxyscirpenol and T-2 toxin were deacetylated to monoacetoxyscirpenol and HT-2 toxin, respectively. Feeding of 5 ppm (5 mg/kg) of ochratoxin A to sheep revealed 14 ppb (14 ng/ml) of ochratoxin A and ochratoxin alpha in rumen fluid after 1 h, but neither was detected in the blood. Whether such conversions in the rumen fluid may be considered as a first line of defense against toxic compounds present in the diet is briefly discussed.     

Site-directed mutagenesis of residues 164, 170, 171, 179, 220, 237 and 242 in PER-1 beta-lactamase hydrolysing expanded-spectrum cephalosporins.

The class A beta-lactamase PER-1, which displays 26% identity with the TEM-type extended-spectrum beta-lactamases (ESBLs), is characterized by a substrate profile similar to that conferred by these latter enzymes. The role of residues Ala164, His170, Ala171, Asn179, Arg220, Thr237 and Lys242, found in PER-1, was assessed by site-directed mutagenesis. Replacement of Ala164 by Arg yielded an enzyme with no detectable beta-lactamase activity. Two other mutants, N179D and A164R+N179D, were also inactive. Conversely, a mutant with the A171E substitution displayed a substrate profile very similar to that of the wild-type enzyme. Moreover, the replacement of Ala171 by Glu in the A164R enzyme yielded a double mutant which was active, suggesting that Glu171 could compensate for the deleterious effect of Arg164 in the A164R+A171E enzyme. A specific increase in kcat for cefotaxime was observed with H170N, whereas R220L and T237A displayed a specific decrease in activity towards the same drug and a general increase in affinity towards cephalosporins. Finally, the K242E mutant displayed a kinetic behaviour very similar to that of PER-1. Based on three-dimensional models generated by homology modelling and molecular dynamics, these results suggest novel structure-activity relationships in PER-1, when compared with those previously described for the TEM-type ESBLs.     

Association of MTHFR, MTR, MTRR, RFC1, and DHFR gene polymorphisms with susceptibility to sporadic colon cancer

Altered folate levels may play an important role in colon carcinogenesis. The aim of this study was to investigate the association of polymorphisms in key folate-metabolizing genes with susceptibility to sporadic colon cancer. Six common polymorphisms (two in MTHFR and one each in MTR, MTRR, RFC1, and DHFR genes) were genotyped in 300 healthy subjects and 300 colon cancer patients from Croatia. Obtained results indicate possible protective role of MTRR 66 AA in sporadic colon cancer (OR=0.655; 95% CI=0.441-0.973; p=0.04). Maximum-likelihood analysis of haplotypes revealed a linkage disequilibrium (LD) between the two investigated polymorphisms of the MTHFR gene (C677T and A1298C), both in the control and patient groups (p<0.01 for both). LD was also detected between MTRR A66G and MTHFR A1298C polymorphisms but only in a group of patients (p<0.01). A haplotype of A66G and A1298C polymorphisms, A/A, proved to be protective (OR=0.775; 95% CI=0.603-0.996; p=0.04), whereas haplotype A/G was a risk factor for colon cancer (OR=1.270; 95% CI=1.007-1.602; p=0.04). Contrary to some previous studies, single-locus analyses identified no polymorphisms associated with risk for colon cancer, but demonstrated a possible protective effect of MTRR 66 AA genotype. The detected significant LD between two loci (MTHFR A1298C and MTRR A66G) located on different chromosomes indicates a strong selective force as a mechanism for the maintenance of their linkage. Specific combinations of alleles of these two polymorphisms showed a protective but also a risk effect on colon cancer susceptibility.     

Metabolism of aflatoxin, ochratoxin, zearalenone, and three trichothecenes by intact rumen fluid, rumen protozoa, and rumen bacteria.

The effect of rumen microbes on six mycotoxins (aflatoxin B1, ochratoxin A, zearalenone, T-2 toxin, diacetoxyscirpenol, and deoxynivalenol ) considered to be health risks for domestic animals was investigated. The mycotoxins were incubated with intact rumen fluid or fractions of rumen protozoa and bacteria from sheep and cattle in the presence or absence of milled feed. Rumen fluid had no effect on aflatoxin B1 and deoxynivalenol . The remaining four mycotoxins were all metabolized, and protozoa were more active than bacteria. Metabolism of ochratoxin A, zearalenone, and diacetoxyscirpenol was moderately or slightly inhibited by addition of milled feed in vitro. The capacity of rumen fluid to degrade ochratoxin A decreased after feeding, but this activity was gradually restored by the next feeding time. Ochratoxin A was cleaved to ochratoxin alpha and phenylalanine; zearalenone was reduced to alpha-zearalenol and to a lesser degree to beta-zearalenol; diacetoxyscirpenol and T-2 toxin were deacetylated to monoacetoxyscirpenol and HT-2 toxin, respectively. Feeding of 5 ppm (5 mg/kg) of ochratoxin A to sheep revealed 14 ppb (14 ng/ml) of ochratoxin A and ochratoxin alpha in rumen fluid after 1 h, but neither was detected in the blood. Whether such conversions in the rumen fluid may be considered as a first line of defense against toxic compounds present in the diet is briefly discussed.     

Safe, convenient, portable pipettor

A dafe, convenient, portable pipetting device that will accommodate any size pipette is described. A vacuum bulb eliminates the need for external vacuum. Necessary components, fabrication procedures, and operating techniques are given.     

Karyotypic analysis of Cajanus,Atylosia, and Rhynchosia species

Summary Somatic chromosomes of two cultivais of Cajanus cajan, eight species of Atylosia (A. albicans, A. cajanifolia, A. lineata, A. platycarpa, A. scarabaeoides, A. serica, A. trinervia and A. volubilis), and of Rhynchosia rothii were analysed. All species had 2n=22. Eight of the 10 species studied had two pairs of satchromosomes while A. scarabaeoides and A. sericea had only one sat-chromosome pair. Based on relative chromosome length (L%), arm ratio (pa-value) and presence or absence of secondary constriction, a karyotype formula for each species was formulated. Based on these parameters the chromosome pairs could also be assigned to groups ranging from 8 to 10 in different species. Except for the asymmetrical karyotype of A. albicans, the other species had rather moderately symmetrical karyotypes.     

Vitamin A,Pregnancy, and Oral Contraceptives

It has been shown that women receiving oral contraceptives have increased levels of serum vitamin A. High vitamin A levels may constitute a teratogenic hazard and it has been suggested that women who conceive soon after discontinuing oral contraceptive therapy may be especially at risk to this hazard.We have confirmed a significant increase in vitamin A levels in women taking oral contraceptives. During early pregnancy there is no significant difference in vitamin A levels between women who have recently been taking oral contraceptives and those who have not. We have been unable to show that either taking oral contraceptives shortly before pregnancy or a high vitamin A level during the first trimester of pregnancy, comparable to that of a woman taking oral contraceptives, has any detrimental effect on the outcome of pregnancy. It seems unlikely that women who conceive soon after discontinuing oral contraception run any teratogenic risk from increased vitamin A levels.     

Evidence of mitochondrial DNA clones of Siberian sturgeon, Acipenser baerii, within Russian sturgeon, Acipenser gueldenstaedtii, caught in the River Volga

Eleven of 34 sturgeons caught in the River Volga classified morphologically as Acipenser gueldenstaedtii were identified as Acipenser baerii from sequence analysis of the mitochondrial cytochrome- b gene. The Caspian Sea and its tributaries including the Volga are not native habitats of A. baerii . No A. baerii haplotype was observed in A. gueldenstaedtii from the Sea of Azov or the South Caspian Sea. Genetic contamination of A. gueldenstaedtii with A. baerii or A. baerii hybrids has occurred in the Volga. Crosses and backcrosses of these specimens with native A. gueldenstaedtii resulted in the loss of the morphological diagnostic A. baerii features. These findings are of special concern for conservation and management programmes, as well as for specimen identification for caviar trading control.     

Patterns of intraspecific variation inAntennaria alborosea,A. corymbosa,A. marginata,A. microphylla,A. parvifolia,andA. umbrinella (Asteraceae:Inuleae)

Patterns of intraspecific variation were examined inAntennaria alborosea A. E. Porsild,A. corymbosa E. Nels,A. marginata Greene,A. microphylla Rydb.,A. parvifolia Nutt., andA. umbrinella Rydb. AlthoughA. alborosea was initially considered arctic in distribution, it became apparent that a southern montane element also exists. Our results suggest that morphological differences between arctic and southern montane specimens represent clinal variation. The additional morphological data for specimens that occur more than 1,500 km south of the species' range as it was initially described result in a better understanding of this once presumed arctic taxon. Morphological variation in the dioecious speciesA. corymbosa, A. marginata, A. microphylla, A. parvifolia, andA. umbrinella was greater between the genders than was geographic variation within each gender. These results demonstrate that both pistillate and staminate specimens must be examined in dioecious species ofAntennaria if morphological variation in the respective species is to be fully understood. Character size or number of broadly distributed species (A. microphylla andA. parvifolia) generally decreased with increasing longitude, whereas characters of species with more restricted distributions (A. alborosea, A. corymbosa, andA. marginata) generally increased in size or number with increasing latitude or longitude.Antennaria umbrinella was an exception in this respect.     

Relationships and taxonomic status of Alternaria radicina, A. carotiincultae, and A. petroselini based upon morphological, biochemical, and molecular characteristics

Alternaria radicina, A. carotiincultae, and A. petroselini are closely related pathogens of umbelliferous crops. Relationships among these fungi were determined based on growth rate, spore morphology, cultural characteristics, toxin production, and host range. Random amplified polymorphic DNA (RAPD) analysis of these species, other species of Alternaria, and closely related fungi was also performed. A. petroselini was readily differentiated from A. radicina and A. carotiincultae on the basis of spore morphology, production of microsclerotia, host range, and RAPD analysis. Alternaria radicina and A. carotiincultae were considerably more similar to each other than to A. petroselini, but could be differentiated on the basis of growth rate, spore morphology, colony morphology, and, to a limited extent, RAPD analysis. When grown on media having a high nutritional content, A. radicina produced a diffusible yellow pigment and crystals of the fungal metabolite radicinin. In contrast, A. carotiincultae produced little or no radicinin. However, when A. carotiincultae was grown on the same medium amended with radicinin, growth rate and colony and conidial morphology were more similar to those of A. radicina. These results suggest that the morphological differences between A. radicina and A. carotiincultae are due, at least in part, to radicinin production, and that these fungi are conspecific. Therefore, we propose that A. carotiincultae be considered a synonym of A. radicina.     

Relationship between lectin, alpha-, beta-glucosidase, and beta-galactosidase activities of Azospirillum]

The activities of alpha-glucosidase, beta-glucosidase, and beta-galactosidase were studied during the isolation and purification of lectins from Azospirillum brasilense Sp7 and Azospirillum lipoferum 59b cells. These enzymatic activities were revealed in crude extracts of surface proteins, protein fraction precipitated with ammonium sulfate or ethanol-acetone mixture, and protein fraction obtained by gel filtration on Sephadex G-75. The distribution of the enzymes between different protein fractions varied among the azospirilla studied. The cofunction of the A. brasilense Sp7 lectin and beta-galactosidase on the cell surface is assumed. A strong interaction between the A. lipoferum 59b lectin and glucosidases was revealed. The lectin from A. lipoferum 59b may possess saccharolytic activity.     

Activation, regulation, and inhibition of DYRK1A

Dual-specificity tyrosine phosphorylation-regulated kinase 1A (DYRK1A) is a protein kinase with diverse functions in neuronal development and adult brain physiology. Higher than normal levels of DYRK1A are associated with the pathology of neurodegenerative diseases and have been implicated in some neurobiological alterations of Down syndrome, such as mental retardation. It is therefore important to understand the molecular mechanisms that control the activity of DYRK1A. Here we review the current knowledge about the initial self-activation of DYRK1A by tyrosine autophosphorylation and propose that this mechanism presents an ancestral feature of the CMGC group of kinases. However, tyrosine phosphorylation does not appear to regulate the enzymatic activity of DYRK1A. Control of DYRK1A may take place on the level of gene expression, interaction with regulatory proteins and regulated nuclear translocation. Finally, we compare the properties of small molecule inhibitors that target DYRK1A and evaluate their potential application and limitations. The β-carboline alkaloid harmine is currently the most selective and potent inhibitor of DYRK1A and has proven very useful in cellular assays.     

Endocytosis,Signaling, and Beyond

The endocytic network comprises a vast and intricate system of membrane-delimited cell entry and cargo sorting routes running between biochemically and functionally distinct intracellular compartments. The endocytic network caters to the organization and redistribution of diverse subcellular components, and mediates appropriate shuttling and processing of materials acquired from neighboring cells or the extracellular milieu. Such trafficking logistics, despite their importance, represent only one facet of endocytic function. The endocytic network also plays a key role in organizing, mediating, and regulating cellular signal transduction events. Conversely, cellular signaling processes tightly control the endocytic pathway at different steps. The present article provides a perspective on the intimate relationships that exist between particular endocytic and cellular signaling processes in mammalian cells, within the context of understanding the impact of this nexus on integrated physiology.Molecular mechanisms governing the remarkable diversity of endocytic routes and trafficking steps are described elsewhere in the literature (see Bissig and Gruenberg 2013; Henne et al. 2013; Burd and Cullen 2014; Gautreau et al. 2014; Kirchhausen et al. 2014; Mayor et al. 2014; Merrifield and Kaksonen 2014; Piper et al. 2014). Moreover, these have been the focus of many studies in the last 30 years, and the topic has been covered by many excellent reviews, making it unnecessary for us to dwell on this aspect any further here (see, for instance, Howes et al. 2010; McMahon and Boucrot 2011; Sandvig et al. 2011; Parton and del Pozo 2013). Herein, we will instead concentrate our attention on how cellular regulatory mechanisms control endocytosis, as well as on how endocytic events impinge on cell functions. Emphasis will be placed, although not exclusively, on studies that analyze cellular networks using holistic approaches and in vivo analysis. Our aim is to give the reader a flavor of the deep embedding of endocytic processes within cellular programs, a concept we refer to as the endocytic matrix (Scita and Di Fiore 2010).