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PubMed1996

[Cat scratch disease. Bartonella henselae antibodies and DNA detection in regional lymphadenopathy].

HISTORY AND CLINICAL FINDINGS: Two hard, pressure-sensitive nodules developed in the lower jaw of a 22-year-old woman. After a dental cause had been excluded, she was treated for suspected tonsillitis with Ceftibuten. Erythrocyte sedimentation rate was increased to 18 mm in the first hour. There were no other significant biochemical findings and fine-needle biopsy of one of the nodules showed nonspecific inflammatory reaction. INVESTIGATIONS: Sonography revealed two lymph nodes, 7 and 22 mm in diameter. Suspected cat scratch disease was confirmed by immunofluorescence with Bartonella (Rochalimaea) henselae and quintana antigens. TREATMENT AND COURSE: After a course of Clarithromycin (250 mg twice daily) for 6 weeks the lymph nodes had shrunk and the overlying skin was thin and discoloured brown. One node was incised and drained and the material examined. Microbiology was negative, but DNA sequencing confirmed Bartonella henselae. As a consequence, Rifampicin was given for 2 months (600 mg daily). Wound healing was very slow and the scar had regressed little after 9 months.

Adult↗
PubMed1983

Nodule-specific host proteins in effective and ineffective root nodules of Pisum sativum.

Nodule-specific root proteins - so called nodulins - were identified in root nodules of pea plants by an immunological assay. Nodulin patterns were examined at different stages of nodule development. About 30 nodulins were detectable during development. Some were preferentially synthesized before nitrogen fixation started, whereas the majority were synthesized concomitantly with leghaemoglobin. Some of the nodulins were located within the peribacteroid membrane. Ineffective Rhizobium strains (a natural nodfix and a pop fix) appeared to be useful in studying the expression of nodulin genes. Synthesis of some nodulins was repressed in ineffective root nodules, indicating that nodulins are essential for the establishment of nitrogen fixation. In both types of ineffective root nodules, leghaemoglobin synthesis was not completely repressed. Low amounts of leghaemoglobin were always detected in young ineffective root nodules whereas in old nodules no leghaemoglobin was present.

Journal Article↗
PubMed1997

Immunoreactive endothelin in nodular pathology of the thyroid.

OBJECTIVES: Endothelins (ETs) can act as autocrine and/or paracrine regulators of thyroid homeostasis and growth. The aim of this study was to evaluate immunoreactive ET (i-ET) levels in a group of patients with nodular pathology of the thyroid and to correlate them with the cytomorphological features after fine-needle aspiration (FNA) and with hormonal and immunological status and blood pressure levels. DESIGN: Plasma and cystic i-ET were assayed in a group of patients with varying thyroid function, who underwent FNA for solid and cystic nodular pathology. PATIENTS: 47 patients (32-81 years) with nodular pathology of the thyroid and 18 controls (28-70 years) with normal thyroid function and morphology were studied. MEASUREMENTS: Fasting venous blood samples were collected and the plasma for i-ET was frozen at -80 degrees C until assayed. Sera were frozen at -20 degrees C for FT3, FT4, TSH, TPO autoantibodies and thyroglobulin autoantibodies assay. Cystic fluid was obtained by FNA, centrifuged, and the supernatant was stored at -20 degrees C until i-ET assay. FNA cytology was examined by light microscopy. RESULTS: In patients with cystic nodules, plasma i-ET levels were significantly (P = 0.002) higher (5.7 +/- 1.1 ng/l, +/- SEM) than in both patients with solid nodules (2.6 +/- 0.4 ng/l) and (P = 0.02) controls (3.0 +/- 0.3 ng/l). In patients with cystic nodules, cystic i-ET levels (12.6 +/- 1.9 ng/l) were significantly (P = 0.003) higher than plasma levels (5.7 +/- 1.1 ng/l) and did not correlate with the percentage of FNA cellularity. i-ET levels in cystic fluid (12.6 +/- 1.9 ng/l) were significantly (P = 0.0001) higher than plasma i-ET levels in both patients with solid nodules and controls. No difference in either plasma or cystic i-ET levels was found in patients with cystic nodules in relation to differences in thyroid function. No difference in plasma i-ET levels was found between patients with solid nodules and controls. In controls, no significant difference in plasma i-ET levels was found between males and females. A negative correlation (r = -0.55, P = 0.02) was found between cystic i-ET levels and systolic and diastolic blood pressure. No correlation between cystic or plasma i-ET levels and FT3, FT4 or TSH was found in any of the subjects studied. CONCLUSIONS: It seems that endothelins do not possess a primary role in determining thyroid function and that the increased levels in cystic fluid found in our subjects could be secondary to cystic nodule development.

Adult↗
PubMed1996

Calcium spiking in plant root hairs responding to Rhizobium nodulation signals.

SUMMARY: Rhizobium lipochitooligosaccharide signal molecules stimulate multiple responses in legume host plants, including changes in host gene expression, cell growth, and mitoses leading to root nodule development. The basis for signal transduction in the plant is not known. We examined cytoplasmic free calcium in host root hairs using calcium-sensitive reporter dyes. Image analysis of injected dyes revealed localized periodic spikes in cytoplasmic calcium levels that ensued after a characteristic lag following signal application. Structural features of the signal molecules required to cause nodulation responses in alfalfa are also essential for stimulating calcium spiking. A nonnodulating alfalfa mutant is defective in calcium spiking, consistent with the possibility that this mutant is blocked in an early stage of nodulation signal perception.

Calcium↗
PubMed2002

The white clover enod40 gene family. Expression patterns of two types of genes indicate a role in vascular function.

Enod40 is one of the genes associated with legume nodule development and has a putative role in general plant organogenesis. We have isolated a small enod40 gene family from white clover (Trifolium repens), with three genes designated Trenod40-1, Trenod40-2, and Trenod40-3, all containing the conserved enod40 regions I and II. Trenod40-1 and Trenod40-2 share over 90% homology in the transcribed regions and high levels of similarity in their upstream regulatory sequences. Trenod40-1 and Trenod40-2 are similar to the enod40 genes of legumes forming indeterminate nodules (group II) and are predominantly expressed in nodules. Trenod40-3 shares only 32.8% identity with Trenod40-1 and Trenod40-2 within the transcribed region. Trenod40-3 is similar to the enod40 genes of legumes with determinate nodules (group I) and is not predominantly expressed in nodules. To our knowledge, this is the first report of both group I- and group II-type enod40 genes being expressed in a single legume species. In situ hybridization studies revealed that Trenod40 genes were highly expressed in non-symbiotic tissues, particularly in stolon nodes during nodal root and lateral shoot development. High levels of Trenod40 transcripts were also present in the vascular bundles of mature plant organs, mainly at sites of intensive lateral transport, suggesting a role in vascular tissue function. The expression pattern of Trenod40 genes was analyzed further using Trenod40 promoter-gus fusions in transgenic white clover and tobacco (Nicotiana tabacum), indicating that white clover and tobacco share the regulatory mechanisms for Trenod40-1/2 promoters and some aspects of Trenod40-3 regulation.

Base Sequence↗
PubMedDate not supplied

ENOD8, a novel early nodule-specific gene, is expressed in empty alfalfa nodules.

The alfalfa ENOD8 nodule-specific gene is expressed in empty nodules elicited by exopolysaccharide-deficient Rhizobium meliloti, and it is expressed early in nodule development. An ENOD8 cDNA was sequenced and found to encode a novel product. Its deduced polypeptide sequence was found to be similar to the nonproline-rich domains of the putative polypeptides encoded by a class of anther-specific genes from Arabidopsis thaliana and Brassica napus. The role of the ENOD8 gene product is predicted to be in nodule organogenesis. ENOD8 is expressed in a developmental pathway triggered as a result of Rhizobium nodulation signal transduction.

Amino Acid Sequence↗
PubMed2003

Lotus japonicus: a new model to study root-parasitic nematodes.

Sedentary plant-parasitic nematodes engage in complex interactions, and induce specialized feeding structures by redirecting plant developmental pathways, and parallels have been observed with rhizobial nodule development on legumes. A model legume would greatly facilitate a better understanding of the differences between parasitic (nematode) and mutualistic (rhizobia and mycorrhizae) symbioses, and we have developed Lotus japonicus as such a model. Conditions for efficient parasitism by root-knot nematode (Meloidogyne spp.) of the widely used Lotus "Gifu" ecotype were established. Features of Lotus biology, such as thin and translucent roots, proved ideal for monitoring the progress of nematode infection both on live specimens and post-staining. We examined L. japonicus mutants with nodulation phenotypes. One, har1, which is a hypernodulated mutant defective in a CLAVATA1-like receptor kinase gene, was found to be hyperinfected by M. incognita. However, another hypernodulated Lotus mutant exhibited the same level of M. incognita infection as wild-type plants. We also established conditions for infection of Lotus by soybean cyst nematode (Heterodera glycines). In contrast to the response to root-knot nematode, the Gifu ecotype is resistant to H. glycines, and elicits a hypersensitive response. This pattern of resistance recapitulates that seen on nematode-resistant soybean plants. We conclude that L. japonicus is a powerful model legume for studying compatible and incompatible plant-nematode interactions.

Animals↗
PubMed2001

The association of cigarette smoking with disease outcome in patients with early inflammatory polyarthritis.

OBJECTIVE: Cigarette smoking is known to increase rheumatoid factor (RF) and nodule formation in patients with rheumatoid arthritis (RA). In this study, we examined the influence of smoking on disease outcome at 3 years among patients newly presenting with inflammatory polyarthritis (IP). METHODS: We studied 486 patients with IP who were referred to the Norfolk Arthritis Register, of whom 323 (67%) satisfied the American College of Rheumatology 1987 criteria for RA. Smoking status was assessed at baseline. Disease outcome was assessed at 3 years, using measures of joint inflammation, functional disability, and radiologic damage. The influence of smoking on disease outcome was explored using logistic regression techniques, with patients who had never smoked as the referent group. Results are expressed as odds ratios (ORs), with their 95% confidence intervals (95% CIs). RESULTS: Current smokers were significantly more likely to be RF positive at baseline (47%) than were ex-smokers (34%) and never smokers (31%). After 3 years, rheumatoid nodules were significantly more common in smokers (13%) compared with ex-smokers/never smokers (4%), a relationship which persisted after adjusting for age and sex (OR 4.07, 95% CI 1.38-12). In contrast, after adjusting for age and sex, current smokers had significantly fewer swollen joints (OR 0.61, 95% CI 0.37-0.98). However, smoking status had no influence on the development of erosions or functional disability. CONCLUSION: Despite smokers being more likely to develop nodules and to be RF positive, current smokers did not have higher levels of radiologic damage, and had fewer swollen joints. We hypothesize that this could be due to either the effect of cigarette smoking on the inflammatory response or other factors (e.g., reduced physical activity in smokers) which may limit joint inflammation and damage.

Adolescent↗
PubMed1991

Differential regulation of cytochrome(s) P450 2B1/2 by phenobarbital in hepatic hyperplastic nodules induced by aflatoxin B1 or diethylnitrosamine plus 2-acetylaminofluorene in male F344 rats.

Phenobarbital (PB) is an effective growth stimulator of hepatic hyperplastic nodules developed with diethylnitrosamine and 2-acetylaminofluorene plus partial hepatectomy (the Solt-Farber model), but it does not apparently stimulate the growth of preneoplastic lesions produced with aflatoxin B1 (AFB). Some studies have suggested a correlation between the induction of specific cytochrome P450 enzymes and the tumor promoting effects produced by repeated treatment with PB. To examine this hypothesis further, hepatic hyperplastic nodules were produced with AFB (10 ip doses of AFB, 150 micrograms/kg/day, followed by partial hepatectomy) or by a modified Solt-Farber protocol (DEN/AAF), and the effects of PB on nodule growth and expression of cytochrome(s) P450 2B1 and/or P450 2B2 (P450 2B1/2) were determined. Both treatment protocols (without PB) produced multiple, large nodules within 10-17 weeks of carcinogen administration. These nodules stained intensely for glutathione S-transferase p (GST-p; GST7-7) and gamma-glutamyl transpeptidase (GGT) and weakly for P450 2B1/2. Pentoxyphenoxazone dealkylation activity was decreased to less than 50% of the surrounding tissue levels in both types of nodules. PB treatment of animals with DEN/AAF-induced nodules greatly increased P450 2B1/2 expression in surrounding tissues, whereas most, but not all, nodules were not inducible. Pentoxyphenoxazone dealkylation was increased 31- to 35-fold in surrounding tissue, but it was increased only 2-fold in pooled nodular tissue, relative to untreated control liver. In contrast to the DEN/AAF group, immunohistochemical staining and pentoxyphenoxazone dealkylation in the AFB group demonstrated that P450 2B1/2 was equally inducible in nodular and surrounding tissues. Short-term treatment (5 days) with PB produced a 2-fold increase in the number and total area of GGT-positive nodules in the DEN/AAF group, but it had no significant effect on the number, size distribution, or total area of GGT-positive nodules in the AFB group. All large GGT-positive nodules in the DEN/AAF group were nonresponsive to induction of P450 2B1/2, whereas all of the GGT-positive nodules which were responsive to P450 2B1/2 induction by PB in this group were relatively small. The size and area of AFB-induced GGT-positive nodules was not affected by PB treatment, and P450 2B1/2 in all of these nodules was inducible by PB. Although a causal, inverse relationship between the responsiveness of nodules to PB induction of P450 2B1/2 and their reaction to PB growth stimulation cannot be firmly established, these data are consistent with such a hypothesis.

2-Acetylaminofluorene↗
PubMed1979

[Cold nodules of the thyroid. Reevaluation of surgical excision on the basis of a new group of 607 patients(author's transl)].

In a serie of 607 cold nodules developing in normal or apparently normal (on preoperative clinical examination) thyroids, the results of histopathological examination were compared with those in an identical series studied 10 years before. Carcinoma was frequent: 9.7% in the current series and 19% in the first series. Insofar as neither clinical examination nor special investigations at the present time make it possible to affirm that a cold nodule is not malignant, surgical complete lobectomy with frozen section examination remains the required procedure in view of its harmless nature and the good prognosis in differentiated tumours operated upon before any visceral extension has taken place, contrasting with the poor prognosis of others. Recurrences may be prevented by special operative techniques (routine excision of Lalouette's pyramid, division of the contralateral ligament of Grubert) and routine postoperative thyroid extracts in patients with a morphological, familial or biological risk of recurrence.

Adenoma↗
PubMed1989

Aspartate aminotransferase in alfalfa root nodules : I. Purification and partial characterization.

Aspartate aminotransferase (l-aspartate:2-oxoglutarate aminotransferase, EC 2.6.1.1 [AAT]), a key enzyme in the assimilation of C and N compounds, was purified from the cytosol of alfalfa (Medicago sativa L.) root nodules. Isoforms that increased during nodule development, AAT-2a, AAT-2b, and AAT-2c, were purified greater than 447-fold to apparent homogeneity, and high titer polyclonal antibodies were produced. The native molecular weight of the AAT-2 isoforms was approximately 80 kilodatons with a subunit molecular weight of 40 kilodatons, indicating that the holoenzymes are dimers. The AAT-2 isoforms comprised approximately 0.4% of the total soluble nodule protein. The AAT specific activity was measured in leaf, stem, root, and nodule organs, and zymograms of each were compared. Enzyme activity was 4- to 37-fold greater in effective (nitrogen fixing) nodules than in leaves, stems, and roots. Effective nodule AAT-specific activity was 3- to 8-fold greater than that of plant-controlled ineffective nodules. No differences in K(m) were observed between AAT-1 and AAT-2. Antibodies raised against AAT-2 were more selective against AAT-2 than AAT-1. Evidence obtained from zymograms suggests that the expression of alfalfa nodule AAT is controlled at two different gene loci, AAT-1 and AAT-2, resulting in different dimeric isoforms.

Journal Article↗
PubMed1991

Glutamate Oxaloacetate Transaminase in Pea Root Nodules : Participation in a Malate/Aspartate Shuttle between Plant and Bacteroid.

Glutamate oxaloacetate transaminase (l-glutamate: oxaloacetate aminotransferase, EC 2.6.1.1 [GOT]), a key enzyme in the flow of carbon between the organic acid and amino acid pools in pea (Pisum sativum L.) root nodules, was studied. By ion exchange chromatography, the presence of two forms of GOT in the cytoplasm of pea root nodule cells was established. The major root nodule form was present in only a small quantity in the cytoplasm of root cells. Fractionation of root nodule cell extracts demonstrated that the increase in the GOT activity during nodule development was due to the increase of the activity in the cytoplasm of the plant cells, and not to an increase in activity in the plastids or in the mitochondria. The kinetic properties of the different cytoplasmic forms of GOT were studied. Some of the K(m) values differed, but calculations indicated that not the kinetic properties but a high concentration of the major root nodule form caused the observed increase in GOT activity in the pea root nodules. It was found that the reactions of the malate/aspartate shuttle are catalyzed by intact bacteroids, and that these reactions can support nitrogen fixation. It is proposed that the main function of the nodule-stimulated cytoplasmic form of GOT is participation in this shuttle.

Journal Article↗
PubMed1993

Centroblastic transformation of chronic lymphocytic leukaemia with primary skin involvement--cutaneous presentation of Richter's syndrome.

The development of a large-cell non-Hodgkin's lymphoma in a patient suffering from chronic lymphocytic leukaemia is known as Richter's syndrome, representing one of the possible anaplastic transformations of the leukaemia. Cutaneous involvement is an extremely rare event. The case of a 45-year-old man with B-cell chronic lymphocytic leukaemia is reported. Five years later multiple cutaneous nodules developed on his extremities. Biopsies of the skin showed a diffuse large-cell lymphoma, bearing the same cell surface immunoglobulin light chain isotype as the leukaemia, suggesting the original relationship between both neoplasms.

Adult↗
PubMed1985

Human B cell development. II. Subpopulations in the human fetus.

In man, during fetal development the B cell populations show distinct phenotypes at different tissue sites. The pre-B and B lymphocytes of the fetal liver and bone marrow express IgM and B cell markers, B1 (CD20) and BA-1 (CD24). These "early" cells are negative with a number of other reagents, anti-IgD, RFB4 (CD22), RFB6 (CD21), and RFA-2, which on the other hand recognize peripheral B cells. These peripheral B lymphocytes in the developing fetus are heterogeneous. The diffusely distributed B cells in the earliest lymph node samples, 16 to 17 wk of gestational age, and from 16 to 21 wk in the spleen, are strongly IgM+ (IgD+,RFB4+,RFB6+, and RFA-2+) but lack T cell-associated markers such as T1 (CD5, p 67,000 dalton equivalent of murine Ly-1) and Tü-33. In fetal lymph nodes, primary nodules develop around the follicular dendritic (FD) cells from 17 wk onward, and contain a virtually pure population of B cells; B1+,BA1+,RFB4+,RFB6+,RFA-2+, which simultaneously express IgM,IgD together with T1 (CD5), a T cell-associated antigen. A sizeable subpopulation of these IgM+,T1+ cells are also positive for Tü-33, another T cell-associated marker. In the spleen, the B cells of the IgM+,IgD+,T1+ type appear in smaller numbers and only relatively late around wk 22. These cells are diffusely distributed at first, and start accumulating around the small FD cell clusters as soon as these emerge about the 23rd gestational wk. At that time, the IgM+,T1+B cells can also be washed out from the peritoneal and pleural cavities. The T1+,IgM+B cells may represent the normal equivalent cells of B chronic lymphoid leukemia and centrocytic lymphoma, and appear to be the counterpart of Ly-1+,IgM+B cells in the mouse.

Adult↗
PubMed1994

In situ hybridization of two nodule-specific gene products from yellow lupin.

We have applied in situ hybridization technique to examine the expression of two tissue-specific plant genes represented by cDNA clones: pLN-13 and pLN-50 during the symbiosis of Lupinus luteus with Bradyrhizobium lupini. Both genes are expressed in root nodules and their transcripts are restricted to the infected zone of the nodule as revealed with 35S-or 3H-labelled antisense RNA probes. The number of grains over bacteroid-containing cells after hybridization with 3H-labelled probes differed during three tested phases of nodule development: at the 14th, 21st and 28th day after the infection with B. lupini. As control, apical root meristems and segments of root hair zones of uninfected plants were used for incubation with RNA of either sense or antisense orientation preceded by RNAse A digestion. The data obtained confirm that both genes are organ-specific and reveal their developmentally regulated expression pattern during the course of root nodule morphogenesis.

Antisense Elements (Genetics)↗
PubMed1994

An Azorhizobium caulinodans ORS571 locus involved in lipopolysaccharide production and nodule formation on Sesbania rostrata stems and roots.

Azorhizobium caulinodans ORS571 is able to nodulate roots and stems of the tropical legume Sesbania rostrata. An ORS571 Tn5 insertion mutant, strain ORS571-X15, had a rough colony morphology, was nonmotile, and showed clumping behavior on various media. When this pleiotropic mutant was inoculated on roots or stems of the host, no nodules developed (Nod-). Compared with the wild type, strain ORS571-X15 produced lipopolysaccharides (LPS) with an altered ladder pattern on sodium dodecyl sulfate-polyacrylamide gel electrophoresis gels, suggestive of a different O-antigen structure with a lower degree of polymerization. A cosmid clone, pRG20, that fully complemented all phenotypes of ORS571-X15 was isolated. With a 6-kb EcoRI subfragment of pRG20, clumping was relieved and nodulation was almost completely restored, but the strain was still nonmotile. LPS preparations from these complemented strains resembled the wild-type LPS, although minor quantitative and qualitative differences were evident. The sequence of the locus hit by the Tn5 in ORS571-X15 (the oac locus) revealed a striking homology with the rfb locus of Salmonella typhimurium, which is involved in O-antigen biosynthesis. The Tn5 insertion position was mapped to the oac3 gene, homologous to rfbA, encoding dTDP-D-glucose synthase. Biochemical assaying showed that ORS571-X15 is indeed defective in dTDP-D-glucose synthase activity, essential for the production of particular deoxyhexoses. Therefore, it was proposed that the O antigen of the mutant strain is devoid of such sugars.

Amino Acid Sequence↗
PubMed2001

Percutaneous needle biopsy of the lung and its impact on patient management.

Percutaneous needle biopsy (PNB) of the lung is a commonly performed procedure, mainly used for the investigation of solitary pulmonary nodules. Developments in imaging, particularly computed tomography (CT), have enable accurate preliminary assessment and targeting of lesions. Improvements in needle design ensure the provision of diagnostic samples for both cytologic and histologic assessment; and the development of immunocytochemistry and immunohistochemistry have allowed improved accuracy in diagnosis. A significant improvement in diagnostic accuracy for benign lesions has been associated with the use of cutting needles that provide cores for histologic diagnosis, in contrast to cytologic analysis from fine-needle aspiration. The complications of PNB are well recorded and have not changed significantly with the newer imaging techniques and needles. The preliminary assessment of solitary pulmonary nodules, and the pretest likelihood of malignancy, has improved using contrast-enhanced CT and positron emission tomography; the latter modality is increasingly having a major impact on the investigation of patients with suspected malignancy. The performance of PNB must always be determined on an individual case basis and when the result is likely to affect management. The complementary roles of PNB, bronchoscopic biopsy, and video-assisted thoracoscopic biopsy continue to evolve.

Biopsy, Needle↗
PubMed1992

Hypomethylation of beta-hydroxy-beta-methyl-glutaryl coenzyme A reductase gene and its expression during hepatocarcinogenesis in the rat.

Our earlier studies had demonstrated that inhibition of DNA methylation following carcinogen treatment potentiated initiation of the carcinogenic process in the rat liver system. The hepatic nodules developed by initiation-promotion protocols showed a characteristic hypomethylation in the cell-cycle-related genes c-fos, c-myc and c-Ha-ras. In the present study we have found that the gene for beta-hydroxy-beta-methyl glutaryl coenzyme A reductase, a major rate-limiting enzyme in the biogenesis of mevalonate, is also hypomethylated at both CCGG and GCGC sites and expressed in hepatic nodules. This gene, however, did not exhibit hypomethylation in CCGG sequences in non-nodular surrounding liver, livers from rats subjected to two-thirds partial hepatectomy, or exposed to initiator alone (1,2-dimethylhydrazine given 18 h after partial hepatectomy) or to diets containing 1% orotic acid alone (promoting regimen). The activity of the enzyme and mevalonate formation are positively correlated with DNA synthesis and cell proliferation--two key components of the carcinogenic process. Taken together, the results suggest that hypomethylation of specific genes occurs in the carcinogenic process and this altered pattern of DNA methylation may play a role in the growth of the nodules.

1,2-Dimethylhydrazine↗