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B Blume

Publications and source records attributed to B Blume.

18 recordsLinked to original sources
PubMed2001

No evidence for binding between resistance gene product Cf-9 of tomato and avirulence gene product AVR9 of Cladosporium fulvum.

The gene-for-gene model postulates that for every gene determining resistance in the host plant, there is a corresponding gene conditioning avirulence in the pathogen. On the basis of this relationship, products of resistance (R) genes and matching avirulence (Avr) genes are predicted to interact. Here, we report on binding studies between the R gene product Cf-9 of tomato and the Avr gene product AVR9 of the pathogenic fungus Cladosporium fulvum. Because a high-affinity binding site (HABS) for AVR9 is present in tomato lines, with or without the Cf-9 resistance gene, as well as in other solanaceous plants, the Cf-9 protein was produced in COS and insect cells in order to perform binding studies in the absence of the HABS. Binding studies with radio-labeled AVR9 were performed with Cf-9-producing COS and insect cells and with membrane preparations of such cells. Furthermore, the Cf-9 gene was introduced in tobacco, which is known to be able to produce a functional Cf-9 protein. Binding of AVR9 to Cf-9 protein produced in tobacco was studied employing surface plasmon resonance and surface-enhanced laser desorption and ionization. Specific binding between Cf-9 and AVR9 was not detected with any of the procedures. The implications of this observation are discussed.

Animals↗
PubMed2000

Deuterium labelled nonylphenols in an in-vitro model of percutaneous absorption of environmental xenoestrogens.

A technical mixture of isomeric nonylphenols NP is formed as rather persistent degradation product of nonionic surfactants and has become widespread in the environment, e.g., in surface waters. Information about possible pathways for incorporation is needed for risk assessments, as NP has estrogenic properties. NP uptake after skin contact was determined using isolated and perfused bovine udders as models for human skin. NP-d2 labelled in the positions ortho to the OH-group was prepared by an exchange procedure which did not measurably change the relative amount of isomers. Samples of udder perfusate, milk equivalent produced during the experiments and skin tissue were taken immediately before administration of 500 mg or 50 mg NP-d2 on an udder skin area of 200 cm2 and then for 5 h. They were analyzed by GC-MS for NP and NP-d2 after cleanup by steam distillation and final extraction with SPME fibres. The results are an unambiguous proof of the penetration of NP into the capillary system of living mammals after skin contact.

Administration, Cutaneous↗
PubMed2000

Phytophthora parasitica elicitor-induced reactions in cells of Petroselinum crispum.

Cultured parsley (Petroselinum crispum) cells respond to treatment with elicitors derived from different species of the genus Phytophthora with transcript accumulation of defense-associated genes and the production of furanocoumarin phytoalexins. Pep-25, an oligopeptide fragment of a Phytophthora sojae 42-kDa cell wall protein, and a cell wall elicitor preparation derived from Phytophthora parasitica (Pp-elicitor) stimulate accumulation of the same gene transcripts and formation of the same pattern of furanocoumarins. Treatment of cultured cells and protoplasts with proteinase-digested Pp-elicitor identified proteinaceous constituents as active eliciting compounds in parsley. Similar to Pep- 25, Pp-elicitor induced effluxes of K+ and Cl- and influxes of protons and Ca2+. Concomitantly, as monitored in aequorin-transgenic parsley cell lines both elicitors induced an immediate increase in the cytoplasmic Ca2+ concentration up to sustained levels of 175 nM (Pp-elicitor) or 300 nM (Pep-25), respectively. The signature of the Ca2+ response differed greatly between the two elicitors tested. Extracellular Ca2+ proved essential for activation of an oxidative burst, MAP kinase activity and phytoalexin production by either elicitor. While Pp-elicitor induced a qualitatively similar spectrum of defense responses as did Pep-25, elicitor-specific quantitative differences in response intensity and kinetics suggest activation of a conserved signaling cascade through separate ligand binding sites.

Apiaceae↗
PubMed2000

Receptor-mediated increase in cytoplasmic free calcium required for activation of pathogen defense in parsley.

Transient influx of Ca(2+) constitutes an early element of signaling cascades triggering pathogen defense responses in plant cells. Treatment with the Phytophthora sojae-derived oligopeptide elicitor, Pep-13, of parsley cells stably expressing apoaequorin revealed a rapid increase in cytoplasmic free calcium ([Ca(2+)](cyt)), which peaked at approximately 1 microM and subsequently declined to sustained values of 300 nM. Activation of this biphasic [Ca(2+)](cyt) signature was achieved by elicitor concentrations sufficient to stimulate Ca(2+) influx across the plasma membrane, oxidative burst, and phytoalexin production. Sustained concentrations of [Ca(2+)](cyt) but not the rapidly induced [Ca(2+)](cyt) transient peak are required for activation of defense-associated responses. Modulation by pharmacological effectors of Ca(2+) influx across the plasma membrane or of Ca(2+) release from internal stores suggests that the elicitor-induced sustained increase of [Ca(2+)](cyt) predominantly results from the influx of extracellular Ca(2+). Identical structural features of Pep-13 were found to be essential for receptor binding, increases in [Ca(2+)](cyt), and activation of defense-associated responses. Thus, a receptor-mediated increase in [Ca(2+)](cyt) is causally involved in signaling the activation of pathogen defense in parsley.

Aequorin↗
PubMed1997

Identification of transposon-like elements in non-coding regions of tomato ACC oxidase genes.

1-aminocyclopropane-1-carboxylate (ACC) oxidase, which catalyses the terminal step in ethylene biosynthesis, is encoded by a small multigene family in tomato that is differentially expressed in response to developmental and environmental cues. In this study we report the isolation and sequencing of approximately 2 kb of 5'-flanking sequence of three tomato ACC oxidase genes (LEACO1, LEACO2, LEACO3) and the occurrence of class I and class II mobile element-like insertions in promoter and intron regions of two of them. The LEA CO1 upstream region contains a 420-bp direct repeat which is present in multiple copies in the tomato genome and is very similar to sequences in the promoters of the tomato E4 and 2A11 genes. The region covering the repeats resembles the remnant of a retrotransposon. Two copies of a small transposable element, belonging to the Stowaway inverted repeat element family, have been found in the 5'-flanking sequence and the third intron of LEACO3.

Amino Acid Oxidoreductases↗
PubMed1997

Expression of ACC oxidase promoter-GUS fusions in tomato and Nicotiana plumbaginifolia regulated by developmental and environmental stimuli.

The enzyme ACC oxidase, catalysing the last step in the biosynthesis of the plant hormone ethylene, is encoded by a small multigene family in tomato, comprising three members, LEACO1, LEACO2 and LEACO3. LEACO1 is the major gene expressed during ripening, leaf senescence, and wounding (Barry et al., 1996). To investigate the transcriptional regulation of ACC oxidase gene expression, chimeric fusions between the beta-glucuronidase reporter gene and 97 bp of 5' UTR plus 124, 396 and 1825 bp, respectively, of 5' untranscribed LEACO1 sequence were constructed and introduced into Lycopersicon esculentum (Mill cv. Ailsa Craig) and Nicotiana plumbaginifolia. Analysis of transgenic tomatoes indicated that the region containing nucleotides -124 to +97 of the LEACO1 gene is sufficient to confer a marked increase in GUS activity during fruit ripening, albeit at very low levels. Fusion of 396 and 1825 bp of LEACO1 upstream sequence resulted in strong and specific induction of GUS expression in situations known to be accompanied by enhanced ethylene production. Reporter gene expression was similar to that of the endogenous LEACO1 gene, with major increases especially during fruit ripening, senescence and abscission of leaves and, to a lesser extent, of flowers. Analysis of transgenic N. plumbaginifolia plants confirmed the pattern of LEACO1 promoter activity detected in tomato leaves and flowers. Reporter gene expression was also induced following wounding, treatment with ethylene, and pathogen infection. Histochemical analysis illustrated localized GUS activity in the pericarp of ripening fruit, abscission zones of senescent petioles and unfertilized flowers, and at wound sites. These results demonstrate that ACC oxidase is regulated at the transcriptional level in a wide range of cell types at different developmental stages and in response to several external stimuli.

Amino Acid Oxidoreductases↗
PubMed1996

Differential expression of the 1-aminocyclopropane-1-carboxylate oxidase gene family of tomato.

The tomato ACC oxidase gene family is comprised of three members designated AC01, AC02 and AC03. These are highly homologous throughout the protein coding regions but do show a degree of sequence divergence within the 3' untranslated regions. These regions have been cloned and used as gene-specific probes to analyse the differential expression of the tomato ACC oxidase gene family in various tissues at different stages of development. Results indicate that all three genes are transcriptionally active and display a high degree of inducibility in a number of organs at various stages of the life cycle. Both AC01 and Ac03 transcripts accumulate during the senescence of leaves, fruit and flowers. In addition, it appears that AC01 is wound-inducible in leaves. All three ACC oxidase genes are expressed during flower development, with each showing a temporally distinct pattern of accumulation. In addition, the ACC oxidase transcripts are also spatially regulated throughout flower development; AC01 is predominantly expressed in the petals and the stigma and style, AC02 expression is mainly restricted to tissues associated with the anther cone whereas AC03 transcripts accumulate in all of the floral organs examined apart from the sepals. ACC oxidase enzyme assays and Western blot analysis indicate that both enzyme activity and ACC oxidase protein increase with transcript abundance in several tissues. The physiological role of the differential expression of the ACC oxidase gene family, in relation to the regulation of ethylene synthesis, during these various developmental processes is discussed.

Aging↗
PubMed1990

[Computerized tomography findings in neck abscess ].

Computed tomography was the diagnostic confirming method in two patients with a necrotic cervical phlegmon caused by an infection of streptococcus pyogenes and candida albicans. A cervical phlegmon is frequently caused by the lymphogenic transmission of diverse primary infections. The time between the primary infection and the appearance of a cervical phlegmon is very varied. In rare cases it is possible that the primary focus will have cured completely. The cervical fasciae separate the neck into three different spaces, which, together with their hypostatic abscess paths, can be visualized using CT. The use of the central veins (e.g., the jugular vein) to administer medication etc. means that the deep cervical phlegmone will continue to be a complication in intensive-care patients.

Candidiasis↗
PubMed1990

Evidence for RNA-Oligonucleotides in Plant Vacuoles Isolated from Cultured Tomato Cells.

We have shown that highly purified vacuoles of suspension-cultured tomato (Lycopersicon esculentum) cells contain RNA-oligonucleotides, using two different approaches to label and detect RNA: (a) in vivo labeling of cellular RNA with [5-(3)H]uridine, followed by preparation of vacuoles from protoplasts and by quantification of radioactively labeled material; and (b) in vitro labeling and analysis on sequencing gels of nucleic acids prepared from tomato vacuoles and their identification as RNA. The intravacuolar location of the RNA found in vacuolar preparations was concluded from analyzing for RNA intact organelles after repeated flotation steps as well as ribonuclease A treatment. About 3% of the RNA in protoplasts was localized within vacuoles, exceeding by severalfold the contribution made by contamination with unlysed protoplasts and subcellular organelles. Investigation of the size distribution of vacuolar RNA revealed an oligonucleotide pattern strikingly different from that which would arise from contaminating protoplasts; vacuolar RNA fragments are considerably shorter than 80 nucleotides. Characterization of these oligoribonucleotides (3'-phosphorylated termini; relatively rich in pyrimidines) as possible products of tomato vacuolar ribonuclease I action, and, in addition, enzymatic hydrolysis of vacuolar RNA by inherent enzyme activities in lysed vacuole preparations support the hypothesis that plant vacuoles are involved in cellular nucleolytic processes.

Journal Article↗
PubMed1985

Correlation between in vitro autoradiographic results and histological WHO grades in human urothelial bladder tumours.

253 biopsy specimens of 106 urinary bladder tumours have been examined by means of in vitro autoradiography and the results compared with the WHO grading. An increase of the average labelling index occurred parallel to increasing WHO grades. However, great inter-tumorous differences in proliferation behaviour existed particularly in papillary G2 and G3 urothelium carcinomas. Possible causes of this heterogeneity are discussed. In vitro autoradiography is a suitable method for the objective characterization of the malignancy potential of urinary bladder tumours.

Adenocarcinoma↗
PubMed1985

[Cancerous and precancerous changes in the tumor margin areas of patients with bladder cancers].

In histologically investigated tumour marginal biopsies of 68 patients with carcinomas of the urinary bladder a great number of findings was detected, which have a decisive influence on the prognosis. Degree of severity and frequency of these changes increase with reducing degree of differentiation of tumours. Hyperplasias of the urothelium, papillary formations and low-degree urothelial dysplasias are not easily to be estimated in the evaluation of their dignity in connection with highly differentiated papillary carcinomas of the urothelium. Multiple biopsies are the prerequisite for a modern therapy planning, in which case the tumour marginal area is of particular importance.

Adenocarcinoma↗
PubMed1984

[Histomorphological variants of carcinoma in situ of the urinary bladder].

31 secondary carcinomas in situ of the urinary bladder have been histologically examined. They exhibit a great variability of their histological features. This is due to the varying rate at which cells lose their specific properties. Besides urothelial carcinomas in situ, a squamous cell carcinoma in situ as well as the intraurothelial formation of malign signet-ring cells have been detected.

Adenocarcinoma, Mucinous↗
PubMed1984

[Urothelial carcinoma of the bladder following cyclophosphamide therapy].

A report is given on a 73-year-old patient in whom a urothelial carcinoma of the urinary bladder developed 11 years after a cyclophosphamide therapy. Taking the international literature into account, possible developmental mechanisms are discussed. Patients who have undergone cyclophosphamide therapy should be subject to constant urological observation as a high-risk group.

Aged↗
PubMed1984

[Histological and autoradiographic studies of the objective characterization of the degree of dysplasia in the urothelium].

282 biopsy specimens of tumorous and tumor-free urinary bladders have been examined by histological and autoradiographical means. There is no recommendation unified on an international scale for the histological classification of intra-urothelial cell and nucleus abnormities . The classification into three degrees of dysplasia is proposed. The exact characterization of urothelium requires additional objective methods. The increase of the average labeling index parallel to the increasing degree of dysplasia has been proved autoradiographically. Moreover, the change of proliferation pattern with the increasing degree of dysplasia points to the loss of physiological regeneration.

Adenocarcinoma↗
PubMed1984

[Histologic and autoradiographic studies on the significance and terminology of von Brunn's nests in biopsies of the bladder mucosa].

Von Brunn's nests have been investigated systematically by means of histology and autoradiography in 201 biopsies of tumour-free and tumorous urinary bladders. They show the same proliferation behaviour like the superimposed urothelium under normal conditions and with inflammatory, metaplastic and dysplastic changes. Their sheltered location permits definite diagnoses even with detached superficial urothelium. In case of cystic transformation, a distinction between pseudoglandular, pseudopapillary and cribriform types is possible. They have to be distinguished from genuine glandular metaplasias in von Brunn's nests. Normal and metaplastic von Brunn's nests do not represent precancerous stages. They are supposed to be a protected proliferation reserve.

Autoradiography↗
PubMed1983

[Cancer of the pancreas: a critical analysis of 214 autopsy records].

Based on the post-mortem findings of 214 cases of pancreatic carcinoma, local complications, distant effects of the tumour and paraneoplastic syndromes are considered in detail. With regard to the complications there are distinct differences between carcinomas of the pancreatic head and tail. The most important local complications turned out to be stenosis of the common bile duct in 58% and alterations of the gastrointestinal tract in 30%.

Adult↗
PubMedDate not supplied

[Macrodactyly of the foot--an unusual, untreated course of many years standing].

This case report represents a 56-year-old patient with macrodactyly of the right foot. This congenital anomaly was not treated surgically before. We resected the gigantic phalanges and metatarsals with preservation of the three main points for walking. The patient is now able to wear fitting shoes.

Foot Deformities, Congenital↗