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PubMed1989

Nitrogen Assimilating Enzyme Activities and Enzyme Protein during Development and Senescence of Effective and Plant Gene-Controlled Ineffective Alfalfa Nodules.

Effective (N(2)-fixing) alfalfa (Medicago sativa L.) and plant-controlled ineffective (non-N(2)-fixing) alfalfa recessive for the in(1) gene were compared to determine the effects of the in(1) gene on nodule development, acetylene reduction activity (ARA), and nodule enzymes associated with N assimilation and disease resistance. Effective nodule ARA reached a maximum before activities of glutamine synthetase (GS), glutamate synthase (GOGAT), aspartate aminotransferase (AAT), asparagine synthetase (AS), and phosphoenolpyruvate carboxylase (PEPC) peaked. Ineffective nodule ARA was only 5% of effective nodule ARA. Developmental profiles of GS, GOGAT, AAT, and PEPC activities were similar for effective and ineffective nodules, but activities in ineffective nodules were lower and declined earlier. Little AS activity was detected in developing ineffective nodules. Changes in GS, GOGAT, AAT, and PEPC activities in developing and senescent effective and ineffective nodules generally paralleled amounts of immunologically detectable enzyme polypeptides. Effective nodule GS, GOGAT, AAT, AS, and PEPC activities declined after defoliation. Activities of glutamate dehydrogenase, malate dehydrogenase, phenylalanine ammonia lyase, and caffeic acid-o-methyltransferase were unrelated to nodule effectiveness. Maximum expression of nodule N-assimilating enzymes appeared to require the continued presence of a product associated with effective bacteroids that was lacking in in(1) effective nodules.

Journal Article↗
PubMed1989

[Result of surgical treatment to benign thyroid tumor].

Surgical results of 81 cases with various benign thyroid tumors were reviewed. All had undergone mainly hemi-lobectomy including isthmectomy and had been followed up for more than 2 years. Sixty-eight (84%) have been well without any complaint. However, 5 of 15 cases with adenomatous goiter (AG) again developed nodule(s) in the remnant thyroid and 1 of 37 cases with adenoma developed cancer in the remnant. In order to prevent recurrence in the cases with AG, total thyroidectomy may be required with the meticulous selection of the case. For the cases with AG which undergone hemilobectomy or lumpectomy, TSH suppression treatment may be also required after surgery. It is of caution that the nodule developed in the thyroid after surgery may be not always the same nodule as primary one.

Adult↗
PubMed1987

Intracavernosal injection in the treatment of impotence: a prospective study of sexual, psychological, and marital functioning.

This study assessed the sexual, psychosocial, and medical impact of intracavernosal injection of papaverine hydrochloride and phentolamine mesylate in the treatment of impotence. Ninety-six percent of patients initially achieved satisfactory erections with injections. Common side effects of self-injections included bruising (26%), nodule development (21%), abnormal liver function tests (7%), and pain (5%). No nodules resulted in penile bending or pain, and no patient discontinued treatment due to nodule development. Dropout rate to date was 35%. Self-injection treatment was associated with increases in erection quality, intercourse frequency, and sexual satisfaction, and decreases in masturbation frequency for patients. Partners also reported increases in intercourse frequency, coital arousal, and satisfaction. Decreases in general psychiatric symptomatology and increases in relationship satisfaction and self-esteem were apparent for patients, but not for partners.

Erectile Dysfunction↗
PubMed2004

The PIN and LAX families of auxin transport genes in Medicago truncatula.

Auxin transport proteins may be involved in nodule development. As a prelude to investigating the roles of these proteins in nodule development, we took advantage of the genetic and molecular resources available in the legume Medicago truncatula to characterize the gene families encoding auxin efflux and influx carriers. We identified ten auxin efflux carrier sequences (MtPINs) and five auxin influx/permease sequences (MtLAXs). The genomic sequence of each of these fifteen genes was determined, the genes were mapped on the publicly available map of M. truncatula, and their expression was examined in shoot and root tissue of nodulating plants. With one exception, transcripts of all MtPIN genes were detected. The expression of MtPIN2 was limited to nodulating roots, while transcripts of all other expressed genes were detected in both shoots and roots. Both the PIN and LAX gene families contain more members in M. truncatula than in Arabidopsis, but the gene families are not significantly expanded. Sequence comparison of the M. truncatula PIN and LAX genes with PIN and LAX genes from other dicots and monocots indicates that both gene families share a common overall structure, with areas of high homology both within M. truncatula and across species boundaries. Molecular phylogenies of both the PIN and LAX gene families were constructed. Combined with intron position and expression data, the phylogenies were used to assign relationships between MtPIN and MtLAX genes and the orthologous Arabidopsis PIN and LAX genes. MtPIN2 and MtPIN7 appear to be the result of a recent gene duplication with subsequent divergence of expression patterns. These results set the stage for the use of these genes in research on the role of auxin in nodulation.

Base Sequence↗
PubMed1995

Correlation between serum prolactin levels and hepatocellular tumorigenesis induced by 3'-methyl-4-dimethylaminoazobenzene in mice.

Ovariectomy at 1 month of age promotes development of hepatocellular adenomatous nodules in female C57BL/6 x DS-F1 mice treated neonatally with 3'-methyl-4-dimethylaminoazobenzene (3'-Me-DAB). Implantation of oestradiol-17 beta (E2) pellets at 1 month of age suppresses nodule development. Since E2 increases serum levels of prolactin, high serum levels of prolactin in mice that have received implants of E2 pellets may play a role in the suppression of hepatocellular tumorigenesis. Therefore, to investigate the role of prolactin in hepatocellular tumorigenesis, we examined development of adenomatous nodules in female mice that had been treated neonatally with 3'-Me-DAB and had undergone ovariectomy at 1 month of age, under various serum levels of prolactin. Treatment of these mice with perphenazine (dopamine antagonist) from 6 months of age or transplantation of pituitary glands under the renal capsule at 6 months of age markedly increased serum levels of prolactin and significantly suppressed the incidence of adenomatous nodules at 12 months of age. Implantation of E2 pellets at 1 month of age increased serum levels of prolactin to a greater extent and further decreased the incidence of adenomatous nodules. Treatment of mice that had received implants of E2 pellets at 1 month of age with bromocriptine (dopamine agonist) from 6 months of age decreased serum levels of prolactin, and was accompanied by an increase in the incidence of nodules. The present results showed that an increase in serum levels of prolactin was accompanied by a decrease in incidence of liver tumours induced by 3'-Me-DAB in mice, suggesting a suppressive effect of prolactin on liver tumorigenesis in mice. Thus, it is possible that the suppressive effect of oestrogen on liver tumorigenesis in mice is mediated, at least in part, by prolactin.

Adenoma↗
PubMed1999

Chronic lymphoedema and angiosarcoma.

Angiosarcoma has frequently been described arising within chronic lymphoedema of the upper limb following mastectomy and radiotherapy for carcinoma of the breast. We report a case of angiosarcoma arising in a lymphoedematous leg that had been subjected to radiotherapy 20 years previously for Hodgkin's disease. The diagnosis was expedited once the patient noticed the development of bleeding nodules. Prognosis of angiosarcoma is poor with treatment options being wide-excision surgery, palliative radiotherapy or chemotherapy. Unusual bruised areas or bleeding nodules developing within chronic lymphoedematous limbs should be biopsied to exclude the diagnosis.

Aged↗
PubMed1990

Enhanced preneoplastic liver lesion development under 'selection pressure' conditions after administration of deoxycholic or lithocholic acid in the initiation phase in rats.

The initiating potential of the secondary bile acids, deoxycholic acid (DCA) and lithocholic acid (LCA), for rat hepatocarcinogenesis was investigated using the development of hyperplastic nodules and/or glutathione S-transferase placental form (GST-P)-positive liver foci as the end point. Five week old male F344 rats were given either basal diet, or diets containing 0.5% DCA or 0.5% LCA for 3 weeks in conjunction with partial hepatectomy performed midway, followed by a selection regimen consisting of 2 weeks feeding of 0.02% 2-acetylaminofluorene diet and a single gastric intubation of carbon tetrachloride. The animals were then placed on either basal diet or a diet containing 0.05% phenobarbital (PB) for 52 weeks. Significantly higher numbers of hyperplastic liver nodules developed in the DCA-treated rats irrespective of PB promotion as compared with the respective control groups. No such increase was evident in the LCA-treated rats. In contrast, both DCA and LCA treatments enhanced the development of GST-P-positive liver foci with or without subsequent PB promotion. Only one hepatocellular carcinoma was diagnosed in a control group animal. The present data indicate that a short period of feeding of DCA and LCA in the initiation stage in conjunction with partial hepatectomy results in enhanced development of preneoplastic liver lesions under selection pressure conditions with or without subsequent PB promotion. They thus confirm and extend our previous finding of enhanced gamma-glutamyltranspeptidase-positive liver foci development in a short-term assay of DCA and LCA, and suggest that these secondary bile acids either possess possible initiating activity or some other priming effect for rat hepatocarcinogenesis.

Animals↗
PubMed2000

Sinorhizobium meliloti nfe (nodulation formation efficiency) genes exhibit temporal and spatial expression patterns similar to those of genes involved in symbiotic nitrogen fixation.

The nfe genes (nfeA, nfeB, and nfeD) are involved in the nodulation efficiency and competitiveness of the Sinorhizobium meliloti strain GR4 on alfalfa roots. The nfeA and nfeB genes are preceded by functional nif consensus sequences and NifA binding motifs. Here, we determined the temporal and spatial expression patterns of the nfe genes in symbiosis with alfalfa. Translational fusions of the nfe promoters with the gusA gene and reverse transcription-polymerase chain reaction analyses indicate that they are expressed and translated within mature nitrogen-fixing nodules and not during early steps of nodule development. Within the nodules the three nfe genes exhibit a spatial expression pattern similar to that of genes involved in symbiotic nitrogen fixation. We show that nfeB and nfeD genes are expressed not only from their own promoters but also from the upstream nfe promoter sequences. Furthermore, with the use of specific antibodies the NfeB and NfeD proteins were detected within the root nodule bacteroid fraction. Finally, NfeB was inmunolocalized in the bacteroid cell membrane whereas NfeD was detected in the bacteroid cytoplasm.

Bacterial Proteins↗
PubMed1999

Methotrexate nodulosis.

Methotrexate (MTX) nodulosis in patients with rheumatoid arthritis treated with MTX has become a well recognized phenomenon. It has not been described in patients receiving MTX for treatment of other diseases, e.g., dermatological or malignant diseases. Recently, MTX nodulosis was described in a patient with psoriasis and arthritis. The pathophysiology and treatment of MTX nodulosis are yet unsettled. We experienced a case with dermatomyositis who developed multiple subcutaneous nodules after treatment with MTX. In our patient, numerous, small, symmetrically distributed, grouped subcutaneous nodules were seen on a V-shaped area of the anterior chest, both axillary areas, and the medial sides of both upper arms and thighs. We histopathologically examined a nodule and started treatment with hydroxychloroquine after discontinuation of MTX. The histopathology revealed septal panniculitis, and the nodules have been under regression. MTX nodulosis may be a drug-specific phenomenon. Discontinuation of MTX and replacement with hydroxychloroquine are recommended in severe cases. Awareness of this entity is important for diagnosing and treating cases of multiple nodules developing after the administration of MTX, which is widely used for many dermatological diseases.

Arm↗
PubMed2005

klavier (klv), a novel hypernodulation mutant of Lotus japonicus affected in vascular tissue organization and floral induction.

A novel hypernodulation mutant line was isolated from Lotus japonicus Miyakojima MG-20 by irradiation with a helium ion beam. This mutant, named klavier (klv), had roots that were densely covered with small nodules. The nodulation zone of klv was significantly wider than that of the wild type. Grafting experiments showed that klv is impaired in the long-distance shoot-to-root autoregulatory mechanism. Thus the shoot genotype was found to be responsible for the negative regulation of nodule development by KLV. Nodulation of klv showed a higher tolerance to nitrogen (KNO3) than the wild type, which is a common feature of hypernodulating mutants. In addition to an increased number of nodules, the klv mutant showed convex leaf veins on the adaxial leaf surface, markedly delayed flowering and dwarf phenotypes. Microscopic examination of the leaf veins revealed that they were discontinuous. Other phenotypes such as fasciated stems, increased number of flowers and bifurcated pistils were also frequently observed in the klv mutant. Among these phenotypes, hypernodulation, aberrant leaf vein formation and significantly delayed flowering were all linked in a monogenic and recessive manner, indicating that these phenotypes are caused by either a single mutation, or tightly linked mutations. KLV was mapped within 0.29 cM on the long arm of chromosome 1.

Flowers↗
PubMed1984

Postnatal breast development of preterm infants. An index of gonadal function.

Development of breast nodules after birth was examined in 17 preterm infants; nodules developed regularly in girls but not boys. It is concluded that the pituitary-gonadal axis of preterm infants is active in the months after birth and that in preterm infants there is a definite phase of breast growth in early postnatal life.

Aging↗
PubMed1978

Subcutaneous mycosis fungoides.

In five cases of mycosis fungoides, previously treated with electron-beam therapy, subcutaneous nodules developed. Clinically, these lesions were thought to be epidermoid cysts or lipomas, but on biopsy were discovered to be subcutaneous infiltrates, three of which were diagnosed as mycosis fungoides. The other two specimens showed only a nonspecific subcutaneous infiltrate. There is no ready explanation for the appearance of these lesions, but it is speculated that they may be the result of inadequate penetration of the electron beam to the depth at which some atypical cells may originally have been located. Patients with mycosis fungoides who develop unusual subcutaneous nodules should be fully investigated so that appropriate and adequate therapy may be initiated.

Adult↗
PubMedDate not supplied

Assessment of the efficacy of diethylcarbamazine on adult Wuchereria bancrofti in vivo.

To assess directly the effect of various doses of diethylcarbamazine (DEC) on adult Wuchereria bancrofti, 31 infected men were randomly assigned to receive an initial single DEC dose of 1 mg/kg (n = 7), 6 mg/kg (n = 10), or 12 mg/kg (n = 14). Beginning 7 d later, the dosage of DEC and duration of treatment were progressively increased for 7-10 weeks. Physical examinations were performed to detect scrotal nodules and the scrotal area was examined by ultrasound (7.5 MHz transducer) to monitor the 'filaria dance sign' (FDS), the characteristic pattern of adult worm movement. Of 53 adult worm 'nests' that were detected by ultrasound, 22 (41.5%) were DEC-sensitive (FDS became non-detectable and a nodule became palpable at the site); 20 (37.7%) were not sensitive (FDS remained unchanged and detectable and no nodule developed), and 11 (20.8%) showed mixed responses (FDS remained detectable but a palpable nodule developed). All but one sensitive or mixed response occurred within 1 week after the initial single dose. Of 39 'nests' in men who initially received a single 6 or 12 mg/kg dose of DEC, 20 (51.3%) had sensitive responses compared to 2 (14.3%) of 14 'nests' in men who received a single 1 mg/kg dose (P = 0.04). Above 6 mg/kg, the macrofilaricidal effect of DEC did not increase with dose; a significant proportion of adult W. bancrofti were not susceptible to DEC during the study period.

Adult↗
PubMed1994

Essentiality of Boron for Symbiotic Dinitrogen Fixation in Pea (Pisum sativum) Rhizobium Nodules.

The effect of boron deficiency on symbiotic nitrogen fixation in pea (Pisum sativum) was examined. The absence of boron in the culture medium resulted in a decrease of the number of nodules and an alteration of nodule development leading to an inhibition of nitrogenase activity. Examination of boron-deficient nodules showed dramatic changes in cell walls and in both peribacteroid and infection thread membranes, suggesting a role for boron in the stability of these structures. These results indicate that boron is a requirement for normal nodule development and functionality.

Journal Article↗
PubMed1979

Separation and determination of the relative concentrations of the homogeneous components of soybean leghemoglobin by isoelectric focusing.

The multiple components of soybean ferric leghemoglobin are readily separated by analytical and preparative flat bed isoelectric focusing in both the presence and also the absence of the ligand nicotinate. In the presence of nicotinate the separation by isoelectric focusing is more rapid and results in sharper bands of the very stable ferric leghemoglobin nicotinate complexes. The separation is sensitive enough to permit analytical experiments on leghemoglobin from single nodules. Leghemoglobins a and c1 prepared by ion exchange chromatography are homogeneous by isoelectric focusing criteria. Leghemoglobin c2 prepared by ion exchange chromatography is an approximately 1:2 mixture of leghemoglobins c2 and c3. Leghemoglobin d consists of three components. The ratio of leghemoglobin a to leghemoglobin c3 content increases dramatically as very young nodules mature. The increase in relative leghemoglobin a content suggests that leghemoglobin a might be required for regulation of nodule O2 concentration only when the nodule structure is complex. The ratio of leghemoglobin c1 content to leghemoglobin c3 content increases somewhat during the early period of nodule development, while the ratio of leghemoglobin c2 content to leghemoglobin c3 content increases slowly throughout nodule development. Ratios of leghemoglobin b content to leghemoglobin a content and of total leghemoglobin d content to total leghemoglobin c content were almost independent of nodule age. Leghemoglobins a and b might be related biosynthetically, as might leghemoglobins c and d.

Hemeproteins↗
PubMed1987

Effect of localized nitrogen availability to soybean half-root systems on photosynthate partitioning to roots and nodules.

Soybean (Glycine max [L.] Merr. cv Davis) was grown in a split-root growth system designed to maintain control of the root atmosphere. Two experiments were conducted to examine how 80% Ar:20% O(2) (Ar:O(2)) and air (Air) atmospheres affected N assimilation (NH(4)NO(3) and N(2) fixation) and the partitioning of photosynthate to roots and nodules. Application of NH(4)NO(3) to nonnodulated half-root systems enhanced root growth and root respiration at the site of application. A second experiment applied Ar:O(2) or air to the two sides of nodulated soybean half-root systems for 11 days in the following combinations: (a) Air to both sides (Air/Air); (b) Air to one side, Ar:O(2) to the other (Air/Ar:O(2)), and (c) Ar:O(2) to both sides (Ar:O(2)/Ar:O(2)). Results indicated that dry matter and current photosynthate ((14)C) were selectively partitioned to nodules and roots where N(2) was available. Both root and nodule growth on the Air side of Air/Ar:O(2) plants was significantly greater than the Ar:O(2) side. The relative partitioning of carbon and current photosynthate between roots and nodules on a half-root system was also affected by N(2) availability. The Ar:O(2) sides partitioned relatively more current photosynthate to roots (57%) than nodules (43%), while N(2)-fixing root systems partitioned 36 and 64% of the carbon to roots and nodules, respectively. The Ar:O(2) atmosphere decreased root and nodule respiration by 80% and nitrogenase activity by 85% compared to half-root systems in Air while specific nitrogenase activity of nodules in Ar:O(2) was 50% of nodules supplied Air. Results indicated that nitrogen assimilation, whether from N(2) fixation or inorganic sources, had a localized effect on root development. Nodule development accounted for the major decrease in total photosynthate partitioning to non-N(2)-fixing nodules. Soybean compensates for ineffective nodulation by controlling the flux of carbon to ineffective nodules and their associated roots.

Journal Article↗
PubMed2006

Spontaneous root-nodule formation in the model legume Lotus japonicus: a novel class of mutants nodulates in the absence of rhizobia.

Root-nodule development in legumes is an inducible developmental process initially triggered by perception of lipochitin-oligosaccharide signals secreted by the bacterial microsymbiont. In nature, rhizobial colonization and invasion of the legume root is therefore a prerequisite for formation of nitrogen-fixing root nodules. Here, we report isolation and characterization of chemically induced spontaneously nodulating mutants in a model legume amenable to molecular genetics. Six mutant lines of Lotus japonicus were identified in a screen for spontaneous nodule development under axenic conditions, i.e., in the absence of rhizobia. Spontaneous nodules do not contain rhizobia, bacteroids, or infection threads. Phenotypically, they resemble ineffective white nodules formed by some bacterial mutants on wild-type plants or certain plant mutants inoculated with wild-type Mesorhizobium loti. Spontaneous nodules formed on mutant lines show the ontogeny and characteristic histological features described for rhizobia-induced nodules on wild-type plants. Physiological responses to nitrate and ethylene are also maintained, as elevated levels inhibit spontaneous nodulation. Activation of the nodule developmental program in spontaneous nodules was shown for the early nodulin genes Enod2 and Nin, which are both upregulated in spontaneous nodules as well as in rhizobial nodules. Both monogenic recessive and dominant spontaneous nodule formation (snf) mutations were isolated in this mutant screen, and map positions were determined for three loci. We suggest that future molecular characterization of these mutants will identify key plant determinants involved in regulating nodulation and provide new insight into plant organ development.

Gene Expression Regulation, Plant↗
PubMed1998

Symbiotic mutants deficient in nodule establishment identified after T-DNA transformation of Lotus japonicus.

Nitrogen-fixing root nodules develop on legumes as a result of an interaction between host plants and soil bacteria collectively referred to as rhizobia. The organogenic process resulting in nodule development is triggered by the bacterial microsymbiont, but genetically controlled by the host plant genome. Using T-DNA insertion as a tool to identify novel plant genes that regulate nodule ontogeny, we have identified two putatively tagged symbiotic loci, Ljsym8 and Ljsym13, in the diploid legume Lotus japonicus. The sym8 mutants are arrested during infection by the bacteria early in the developmental process. The sym13 mutants are arrested in the final stages of infection, and ineffective nodules are formed. These two plant mutant lines were identified in progeny from 1112 primary transformants obtained after Agrobacterium tumefaciens T-DNA-mediated transformation of L. japonicus and subsequent screening for defects in the symbiosis with Mesorhizobium loti. Additional nontagged mutants arrested at different developmental stages were also identified and genetic complementation tests assigned all the mutations to 16 monogenic symbiotic loci segregating recessive mutant alleles. In the screen reported here independent symbiotic loci thus appeared with a frequency of approximately 1.5%, suggesting that a relatively large set of genes is required for the symbiotic interaction.

Crosses, Genetic↗