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PubMed1995

The diagnostic accuracy of a solitary pulmonary nodule, using thin-section high resolution CT: a solitary pulmonary nodule by HRCT.

A solitary pulmonary nodule (SPN) less than 2 cm in diameter of 60 patients was evaluated with thin-section, high-resolution computed tomography (HRCT). The presence of an irregular margin, speculation, convergence of the surrounding structure, an air bronchogram and the involvement of more than 3 vessels was observed more frequently in malignant nodules than in benign nodules. When one point was given for each finding, the mean total scores of each histologic type were as follows; adenocarcinoma; 2.7, squamous cell carcinoma; 2.5, benign tumor; 0.3, tuberculosis; 1.3, pneumonia; 2.0. When SPNs were classified by the total scores, the SPNs with higher scores (> or = 3) included 18 of 33 (56%) malignant lesions and only 2 of 28 (7%) benign lesions. This means that sensitivity and specificity in the diagnosis of malignancy in the SPNs with high scores were 56% and 93%, respectively. These observations suggest that SPNs with a score higher than 3 points would be highly suspicious for malignancy but the number of such SPNs is rather limited. Therefore, more sophisticated methods may be necessary to better differentiate between malignant and benign SPNs.

Adenocarcinoma↗

PubMed1994

Different mutations of the p53 gene in nodule-in-nodule hepatocellular carcinoma as a evidence for multistage progression.

The p53 gene was analysed for mutation in three macro- and micro-scopically different areas of a nodule-in-nodule hepatocellular carcinoma (HCC). Two inner nodules revealed distinct mutations while the surrounding early HCC lesion was negative for mutation. This case clearly demonstrated that the p53 mutation was associated with the progression of HCC from an early to a more advanced stage, and that the primary HCC lesion was composed of genetically heterogeneous subclones. These findings provide direct proof of the involvement of genetic abnormalities in one step of multistage tumor progression.

Carcinoma, Hepatocellular↗

PubMed1997

Rapid nodule evaluation computer-aided image analysis procedure for bone nodule quantification.

Using bone cell cultures, the effects of drugs on cell activities such as proliferation, differentiation, matrix formation, and mineralization can be explored. To quantify these parameters accurately and quickly, a kinetic reproducible computed image analysis procedure of culture dishes is proposed which could be conjointly used with biochemical analysis of the medium. In the present article, different mathematical procedures coupled either with or without histochemical staining are investigated and analyzed. Using serial cross sections and microradiographies of bone nodules, we demonstrated that the gray-level parameter is well correlated with bone mass and/or the mineralization status of the nodules. The procedure selected is a multistep procedure called rapid nodule evaluation (RNE), which uses a binary reconstruction program with different thresholds. To challenge this RNE procedure with the classical Von Kossa staining and quantification procedure, we cultured the cells in the presence of 10 nmol/L dexamethasone and compared the results using the two procedures. The RNE procedure appeared to be accurate and reproducible, and also has the advantage of speed and dynamic analysis over the classical Von Kossa quantification procedure.

Animals↗

PubMed2004

Magnesium-content of Rhizobium nodules in different plants: the importance of magnesium in nitrogen-fixation of nodules.

OBJECTIVE: Rhizobium bacteria induce nodules (tumors) in roots of leguminous crops that fix nitrogen (N2) from the atmosphere. METHODS: Trials were carried on in sterile perlite where two species of peas were grown hydroponically, and in two different soil types (brown forest soil and meadow silt soil), in a field where different leguminous plants were chosen for test plants: lupin, soybean, broad-bean, lentil and bean inoculated by Rhizobium bacteria. The Mg-content of the nutrient solution was higher than that of the control, but in the soil tests 1% Mg leaf fertilization was applied after bacterial inoculation. Number, weight and Mg-content of nodules were evaluated using an AAS method compared with the thick and thin hair/roots of the given plant. RESULTS AND CONCLUSIONS: Our results clearly show that the Mg nutrition treatment increased the number of Rhizobium nodules and their Mg-content, resulting in increased N2-fixation and yield.

Fabaceae↗

PubMed2004

Nodule-enhanced protease inhibitor gene: emerging patterns of gene expression in nodule development on Sesbania rostrata.

A novel marker for the early stages of nodulation of Sesbania rostrata was found to encode a putative member of the Kunitz family of protease inhibitors (SrPI1). Its expression was enhanced during nodulation, and was not up-regulated by wounding or upon infection with wide host-range pathogens. In situ expression patterns resembled those previously described for functions that may be implicated in delimiting infected nodule tissues from the rest of the plant. Thus, SrPI1 may be a component of a multi-layered barrier that restrains the invading rhizobia.

Amino Acid Sequence↗

PubMed2006

Thirteen nodule-specific or nodule-enhanced genes encoding products homologous to cysteine cluster proteins or plant lipid transfer proteins are identified in Astragalus sinicus L. by suppressive subtractive hybridization.

Thirteen nodule-specific or nodule-enhanced genes have been revealed by suppressive subtractive hybridization (SSH) with two mRNA populations of infected and uninfected control roots of Astragalus sinicus. Eleven of them encode small polypeptides showing homology to cysteine cluster proteins (CCPs) that contain a putative signal peptide and conserved cysteine residues. Among these CCP-like genes, AsG257 codes for a homologue of the defensin 2 family and AsD255 contains a scorpion toxin-like domain at the C-terminus. Sequence analysis of a genomic AsD255 fragment which was isolated revealed that one intron separates the first exon encoding the signal peptide from the second exon encoding the cysteine cluster domain of this nodulin. Another two genes, AsE246 and AsIB259, encode two different products similar to lipid transfer proteins (LTPs). Virtual northern blot and reverse transcription-polymerase chain reaction (RT-PCR) analysis indicated that the other genes except AsIB259 and AsC2411 were expressed exclusively in inoculated roots and that their expression was 2-4 d later than that of the leghaemoglobin (Lb) gene during nodule development. Transcription of AsIB259 was also detected in uninfected control roots but with a significant decline in expression and a temporal expression similar to Lb. AsC2411 had a basal expression in control roots identified by RT-PCR. Sequence alignment showed that the putative proteins AsE246 and AsIB259 show lower homology with LTPs from legumes than with those from other plants.

Alphaproteobacteria↗

PubMedDate not supplied

DNA sequence of the common nodulation genes of Bradyrhizobium elkanii and their phylogenetic relationship to those of other nodulating bacteria.

A 6.6-kb BamHI fragment containing the common nodulation genes of Bradyrhizobium elkanii USDA94 was identified by southern hybridization using the common nod genes of B. japonicum as a probe. This fragment was cloned and sequenced. Analysis of the sequence showed open reading frames highly homologous to nolA, nodD2, nodD1, and nodKABC from other bradyrhizobial sources. The sequence showed higher homology to the common nod genes of Bradyrhizobium sp. (Parasponia) than to those from B. japonicum. The open reading frame identified between nodD1 and nodA in the B. elkanii sequence was far more similar to nodK from Bradyrhizobium sp. (Parasponia) than to nodY from B. japonicum. The molecular phylogeny of nodD and nodAB from many sources was analyzed. The genetic distance between the nod genes is far greater than the distance between the 16S rRNA and nifH genes. The differences between the nod genes among the species of Rhizobium is as great as that between Bradyrhizobium and Rhizobium. The host range of the microsymbiont was found to be a better predictor of the similarities of the common nod genes than the 16S rRNA or nifH genes. We propose two groups of nod genes among the rhizobia and bradyrhizobia, based on molecular phylogenetic analysis: those which nodulate legumes of temperate origin in the tribes Vicieae or Trifolieae and those which nodulate legumes of tropical origin in the tribe Phaseoleae.

Amino Acid Sequence↗

PubMedDate not supplied

GmN56, a novel nodule-specific cDNA from soybean root nodules encodes a protein homologous to isopropylmalate synthase and homocitrate synthase.

We have isolated a novel nodule-specific cDNA clone, GmN56, from soybean root nodules. The expression of GmN56 was induced almost concomitantly with the onset of nitrogen fixation, together with leghemoglobin and other late nodulin genes. In situ hybridization studies demonstrated the localization of GmN56 mRNA in the bacterial infected cells of mature nodules. The predicted amino acid sequence of the GmN56 protein exhibits significant homology to those of LeuA (isopropylmalate synthase) of several microorganisms and NifV (putative homocitrate synthase) of nitrogen-fixing bacteria, suggesting that GmN56 encodes an enzyme catalyzing a reaction involving acetyl-CoA and alpha-keto acid as substrates.

2-Isopropylmalate Synthase↗

PubMed1996

Genetic diversity among Frankia strains nodulating members of the family Casuarinaceae in Australia revealed by PCR and restriction fragment length polymorphism analysis with crushed root nodules.

DNA extracted directly from nodules was used to assess the genetic diversity of Frankia strains symbiotically associated with two species of the genus Casuarina and two of the genus Allocasuarina naturally occurring in northeastern Australia. DNA from field-collected nodules or extracted from reference cultures of Casuarina-infective Frankia strains was used as the template in PCRs with primers targeting two DNA regions, one in the ribosomal operon and the other in the nif operon. PCR products were then analyzed by using a set of restriction endonucleases. Five distinct genetic groups were recognized on the basis of these restriction patterns. These groups were consistently associated with the host species from which the nodules originated. All isolated reference strains had similar patterns and were assigned to group 1 along with six of the eight unisolated Frankia strains from Casuarina equisetifolia in Australia. Group 2 consisted of two unisolated Frankia strains from C. equisetifolia, whereas groups 3 to 5 comprised all unisolated strains from Casuarina cunninghamiana, Allocasuarina torulosa, and Allocasuarina littoralis, respectively. These results demonstrate that, contrary to the results of previous molecular studies of isolated strains, there is genetic diversity among Frankia strains that infect members of the family Casuarinacaeae. The apparent high homogeneity of Frankia strains in these previous studies probably relates to the single host species from which the strains were obtained and the origin of these strains from areas outside the natural geographic range of members of the family Casuarinaceae, where genetic diversity could be lower than in Australia.

Actinomycetales↗

PubMed1968

Bacteriology of manganese nodules: III. Reduction of MnO(2) by two strains of nodule bacteria.

MnO(2) reduction by aerobic growing cultures of Bacillus 29 and coccus 32, isolated from ferromanganese nodules, was assessed for 7 days. A 1-day lag was observed before the onset of MnO(2) reduction by either culture. Addition of HgCl(2) to a final concentration of about 10 M caused a rapid cessation of MnO(2) reduction by the growing cultures. Neither culture reduced MnO(2) when grown under continued anaerobiosis from the start of an experiment. However, if conditions were made anaerobic after MnO(2) reduction was initiated, reduction continued at a rate only slightly lower than that under aerobic conditions. Resting-cell cultures reduced MnO(2) equally well aerobically and anaerobically, provided that ferricyanide was present to serve as electron carrier. These findings showed that oxygen is needed for culture adaptation to MnO(2) reduction, and that oxygen does not interfere with microbial MnO(2) reduction itself. Both cultures caused sharp drops in the pH of the medium during MnO(2) reduction: with coccus 32, during the entire incubation time; with Bacillus 29, for the first 3 days. The E(h) of the medium fluctuated with either culture and never fell below 469 mv with Bacillus 29 and below 394 mv with coccus 32. The rates of glucose consumption and Mn release by Bacillus 29 and coccus 32 were fairly constant, but the rates of lactate and pyruvate production were not. Although acid production undoubtedly helped in the reduction of pyrolusite (MnO(2)) by the bacteria, it did not appear to be important in the reduction of manganese oxide in ferromanganese nodules, as shown by the results with a nodule enrichment.

Journal Article↗

PubMed1980

Hydrogenase in actinorhizal root nodules and root nodule homogenates.

Hydrogenases were measured in intact actinorhizal root nodules and from disrupted nodules of Alnus glutinosa, Alnus rhombifolia, Alnus rubra, and Myrica pensylvanica. Whole nodules took up H2 in an O2-dependent reaction. Endophyte preparations oxidized H2 through the oxyhydrogen reaction, but rates were enhanced when hydrogen uptake was coupled to artificial electron acceptors. Oxygen inhibited artifical acceptor-dependent H2 uptake. The hydrogenase system from M. pensylvanica had a different pattern of coupling to various electron acceptors than the hydrogenase systems from the alders; only the bayberry system evolved H2 from reduced viologen dyes.

Actinomycetales↗

PubMed1995

In vitro sulfotransferase activity of NodH, a nodulation protein of Rhizobium meliloti required for host-specific nodulation.

Early stages of nodulation involve the exchange of signals between the bacterium and the host plant. Bacterial nodulation (nod) genes are required for Rhizobium spp. to synthesize lipooligosaccharide morphogens, termed Nod factors. The common nod genes encode enzymes that synthesize the factor core structure, which is modified by host-specific gene products. Here we show direct in vitro evidence that Rhizobium meliloti NodH, a host-specific nodulation gene, catalyzes the transfer of sulfate from 3'-phosphoadenosine 5'-phosphosulfate to the terminal 6-O position of Nod factors, and we show substrate requirements for the reaction. Our results indicate that polymerization of the chitooligosaccharide backbone likely precedes sulfation and that sulfation is not absolutely dependent on the presence or the particular structure of the N-acyl modification. NodH sulfation provides a tool for the enzymatic in vitro synthesis of novel Nod factors, or putative Nod factors intermediates, with high specific activity.

Bacterial Proteins↗

PubMedDate not supplied

[Microstructure of pea nodules infected with a neomycin-resistant mutant of nodule bacteria].

The neomycin-resistance mutation of pea nodule bacteria does not interfere with the formation of infection threads when the bacterium inoculates the host plant, or with the axial differentiation of the nodular tissue. At the same time, intracellular neomycin-resistant nodule bacteria do not acquire the bacteroid structure. Once the bacterium is incorporated into the cytoplasm of the host cell, it loses the peribacteroid membrane and undergoes lysis. Therefore, the neomycin-resistant pea nodule bacterium realizes the initial infection stage (including the formation of infection threads), but is defective in the subsequent stages. Hence, the described stages of plant infection are determined by independent properties of the bacterium.

Drug Resistance, Microbial↗

PubMed1975

The forgotten nodule: complications of sacral nodules in rheumatoid arthritis.

Nodules commonly occur in rheumatoid arthritis and occasionally give rise to complications. The sacral nodule is easily missed and may ulcerate to produce extensive sacral sores which may lead to serious and even fatal complications in patients with rheumatoid arthritis. Seven cases are reported which illustrate some of these features.

Aged↗

PubMed2001

Fine-needle aspiration cytology of umbilical nodules: "Sister Joseph's nodule".

Metastatic tumor deposits in the umbilicus are not uncommon. Fine-needle aspiration cytology is an important, simple, cost-effective diagnostic tool for delineating the value of umbilical nodules. However, only a few reviews and case reports of diagnosis of umbilical metastases by fine-needle aspiration cytology are available. A review of 52 cases of umbilical nodule aspirates over a 16-yr period forms the basis of this brief report.

Abdominal Neoplasms↗

PubMed1995

Induction of nodule primordia on Phaseolus and Acacia by lipo-chitin oligosaccharide nodulation signals from broad-host-range Rhizobium strain GRH2.

Rhizobium wild-type strain GRH2 was originally isolated from the tree, Acacia cyanophylla, and has a broad host-range which includes herbaceous legumes, such as Phaseolus and Trifolium species. Here we show that strains of Rhizobium sp. GRH2, into which heterologous nodD alleles have been introduced, produce a large diversity of both sulphated and non-sulphated lipo-chitin oligosaccharides (LCOs). Most of the molecular species contain an N-methyl group on the reducing-terminal N-acetyl-glucosamine. The LCOs vary in the nature of the fatty acyl chain and in the length of the chitin backbone. The majority of the LCOs have an oligosaccharide chain length of five GlcNAc residues, but a few are oligomers having six GlcNAc units. LCOs purified from GRH2 are able to induce root hair formation and deformation on Acacia cyanophylla and A. melanoxylon plants. We show that an N-vaccenoyl-chitopentaose bearing an N-methyl group is able to induce nodule primordia on Phaseolus vulgaris, A. cyanophylla, and A. melanoxylon, indicating that for these plants an N-methyl modification is sufficient for nodule primordia induction.

Carbohydrate Conformation↗

PubMed1991

Six nodulation genes of nod box locus 4 in Rhizobium meliloti are involved in nodulation signal production: nodM codes for D-glucosamine synthetase.

The nucleotide sequence of the nod box locus n4 in Rhizobium meliloti was determined and revealed six genes organized in a single transcriptional unit, which are induced in response to a plant signal such as luteolin. Mutations in these genes influence the early steps of nodule development on Medicago, but have no detectable effect on Melilotus, another host for R. meliloti. Based on sequence homology, the first open reading frame (ORF) corresponds to the nodM gene and the last to the nodN gene of Rhizobium leguminosarum. The others do not exhibit similarity to any genes sequenced so far, so we designated them as nolF, nolG, nolH and nolI, respectively. We found that the n4 locus, and especially the nodM and nodN genes, are involved in the production of the root hair deformation (Had) factor. NodM exhibits homology to amidotransferases, primarily to the D-glucosamine synthetase encoded by the glmS gene of Escherichia coli. We demonstrated that in E. coli the regulatory gene nodD together with luteolin can activate nod genes. On this basis we showed that nodM complemented an E. coli glmS- mutation, indicating that nodM can be considered as a glmS gene under plant signal control. Moreover, exogenously supplied D-glucosamine restored nodulation of Medicago by nodM mutants. Our data suggest that in addition to the housekeeping glmS gene of R. melioti, nodM as a second glmS copy provides glucosamine in sufficient amounts for the synthesis of the Had factor.

Amino Acid Sequence↗

PubMed2005

Studies on manganese nodule leached residue 4. Physicochemical characterization and catalytic activity of acetic acid treated manganese nodule leached residue.

The catalytic activity of water-washed manganese nodule leached residue (WMNLR) samples improved by treating with acetic acid. The effects of acetic acid treatment on the physicochemical properties and catalytic activity of manganese nodule leached residue have been studied. The surface area, surface oxygen, surface hydroxyl groups, surface acidity, electron donating properties, etc., increase gradually with acid treatment up to 0.5 M and thereafter show a decreasing trend. The rate constant of H2O2 decomposition, catalytic activity of CO oxidation, and esterification of acetic acid also show a similar trend to that of surface properties.

Journal Article↗