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PubMed1988

A case of Graves' disease associated with an autonomously functioning thyroid nodule (AFTN) (Marine-Lenhalt syndrome) which spontaneously became a cold nodule.

We report a 31-year-old female with Graves' disease associated with an autonomously functioning thyroid nodule (AFTN) (Marine-Lenhalt syndrome) in which the AFTN spontaneously became a cold nodule. Initially the patient was thyrotoxic and had diffuse goiter with an elevated radioiodine uptake. She became euthyroid following six months of antithyroid drug therapy, and in addition to diffuse goiter, the solitary hot nodule was palpable in the left lobe. Fourteen months later, hyperthyroidism recurred and the thyroid scan revealed diffuse radioiodine uptake with a cold area in the nodular region. The resected nodule showed extensive degeneration and the histological diagnosis was follicular adenoma with Graves' disease. We discussed the significance of recognizing the syndrome and also compared the frequency of spontaneous degeneration in AFTN and in solitary cold nodules.

Adult↗

PubMedDate not supplied

Thyroid carcinoma in single cold nodules and in cold nodules of multinodular goiters.

OBJECTIVE: To examine the frequency of malignant growth in a nonfunctioning solitary thyroid nodule (SN) and in multinodular goiter (MNG). METHODS: We performed fine-needle aspiration biopsy (FNAB) of cold nodules in 154 patients. Eight patients with unsatisfactory FNAB specimens were excluded from the study. Of the remaining 146 patients, 95 (89 women and 6 men) had MNG. The other 51 patients (46 women and 5 men) had SN. The overall age range was 25 to 86 years (mean, 52). RESULTS: Of the 95 patients with MNG, 16 had abnormal cytologic findings and underwent surgical excision. Of these 16 patients, 12 had thyroid cancer (6 papillary, 3 follicular, and 3 Hürthle cell). Of the 51 patients with SN, 8 had suspicious cytologic findings, and 5 had surgical histologic evidence of thyroid cancer (3 papillary and 2 follicular). Four patients with papillary thyroid cancer (three from the MNG group and one from the SN group) had a history of exposure to neck irradiation. After exclusion of the patients with a history of neck irradiation, the rate of malignant involvement in cold nodules in the MNG group was 9.78%, in comparison with 8% in the group with SN (P = 0.89). Within the MNG group, 25% of the thyroid malignant lesions were of the Hürthle cell type. CONCLUSION: Multinodularity of a goiter should no longer be considered an indicator of probable benign disease. In the assessment of all thyroid nodules, both SN and those in MNG, a thyroid scan can be helpful, and it should be followed by FNAB and cytopathologic examination of any nonfunctioning lesions. The incidence of malignant involvement in cold nodules of MNG does not differ significantly from that found in SN.

Adult↗

PubMed1993

Pathology and DNA cytophotometry of small hepatocellular carcinoma with a nodule-in-nodule appearance--evidence for stepwise progression of hepatocellular carcinoma.

Among 92 surgically resected human hepatocellular carcinomas (HCCs) < or = 3 cm in diameter, 23 tumors (25%) grossly showed a nodule-in-nodule appearance indicating stepwise progression of HCC. The central nodules showed destructive growth of HCC, which was less differentiated than the surrounding area histologically, while the surrounding area showed growth of very-well-differentiated HCC with no, or only minimal, destruction of the underlying liver structures. Previously, we proposed the term "early HCC" for HCCs without definite destructive growth, and the nodule-in-nodule lesions described here are considered to be in the transitional stage from early HCC to advanced HCC, and are therefore named early advanced HCC (eAd HCC). DNA cytophotometry was performed in 12 cases of eAd HCC, in which the early HCC component, advanced HCC component and non-tumorous liver tissue showing chronic hepatitis or cirrhosis were analyzed separately. The early HCC component showed a diploid pattern in eight of the 12 cases. The advanced HCC component showed an aneuploid peak in seven cases, and in three of these the peak was detected only in the advanced HCC component and not in the early HCC component. The mean nuclear DNA content was significantly increased from non-tumorous liver to the early HCC component and from the early HCC component to the advanced HCC component. Polyploid cells containing more than 4.8C DNA were exceptional in non-tumorous liver, but were detectable in the early HCC component and increased in number in the advanced HCC component. These findings suggest that DNA instability may have an important role to play in the subclonal progression of human HCC.

Adult↗

PubMed1997

The probability of malignancy in solitary pulmonary nodules. Application to small radiologically indeterminate nodules.

BACKGROUND: A clinical prediction model to identify malignant nodules based on clinical data and radiological characteristics of lung nodules was derived using logistic regression from a random sample of patients (n = 419) and tested on data from a separate group of patients (n = 210). OBJECTIVE: To use multivariate logistic regression to estimate the probability of malignancy in radiologically indeterminate solitary pulmonary nodules (SPNs) in a clinically relevant subset of patients with SPNs that measured between 4 and 30 mm in diameter. PATIENTS AND METHODS: A retrospective cohort study at a multispecialty group practice included 629 patients (320 men, 309 women) with newly discovered (between January 1, 1984, and May 1, 1986) 4- to 30-mm radiologically indeterminate SPNs on chest radiography. Patients with a diagnosis of cancer within 5 years prior to the discovery of the nodule were excluded. Clinical data included age, sex, cigarette-smoking status, and history of extrathoracic malignant neoplasm, asbestos exposure, and chronic interstitial or obstructive lung disease; chest radiological data included the diameter, location, edge characteristics (eg, lobulation, spiculation, and shagginess), and other characteristics (eg, cavitation) of the SPNs. Predictors were identified in a random sample of two thirds of the patients and tested in the remaining one third. RESULTS: Sixty-five percent of the nodules were benign, 23% were malignant, and 12% were indeterminate. Three clinical characteristics (age, cigarette-smoking status, and history of cancer [diagnosis, > or = 5 years ago]) and 3 radiological characteristics (diameter, spiculation, and upper lobe location of the SPNs) were independent predictors of malignancy. The area (+/-SE) under the evaluated receiver operating characteristic curve was 0.8328 +/- 0.0226. CONCLUSION: Three clinical and 3 radiographic characteristics predicted the malignancy in radiologically indeterminate SPNs.

Adolescent↗

PubMedDate not supplied

Solitary pulmonary nodules: Part II. Evaluation of the indeterminate nodule.

Various strategies may be used to evaluate indeterminate solitary pulmonary nodules. Growth rate assessment is an important and cost-effective step in the evaluation of these nodules. Clinical features (eg, patient age, history of prior malignancy, presenting symptoms, smoking history) can be useful in suggesting the diagnosis and aiding in management planning. Bayesian analysis allows more precise determination of the probability of malignancy (pCa). Decision analysis models suggest that the most cost-effective management strategy depends on the pCa for a given nodule. At contrast material-enhanced computed tomography, nodular enhancement of less than 15 HU is strongly predictive of a benign lesion, whereas enhancement of more than 20 HU typically indicates malignancy. At 2-[fluorine-18]fluoro-2-deoxy-D-glucose (FDG) positron emission tomography, lesions with low FDG uptake are typically benign, whereas those with increased FDG uptake are typically malignant. Results of transthoracic needle aspiration biopsy influence management in approximately 50% of cases and, in indeterminate lesions with a pCa between 0.05 and 0.6, is the best initial diagnostic procedure. It is optimally used in peripheral nodules and has been reported to establish a benign diagnosis in up to 91% of cases. Although there is no one correct management approach, the ability to distinguish benign from malignant solitary pulmonary lesions has improved with the use of these strategies.

Bayes Theorem↗

PubMed2006

Survival, nodulation and N2 fixation ability of root nodule bacteria under different nutritional regimes.

Eleven strains of Rhizobium and five strains of Bradyrhizobium were examined for their viability as well nodulation and nitrogen fixation ability after storage under different conditions for two years. The storage conditions comprised lateritic soil, lateritic soil plus 1% mannitol, lateritic soil plus 0.1% yeast extract, lateritic soil plus 1% mannitol and 0.1% yeast extract, organic soil, organic soil plus 1% mannitol, organic soil plus 0.1% yeast extract, organic soil plus 1% mannitol and 0.1% yeast extract, and sterile distilled water. All the slow growing strains showed better viability than the fast growing strains in any of these conditions. The survived strains maintained their nodulation ability about 50-60% after one year and 40-50% after two years of preservation as compared to control, but the nodulation ability in sterile distilled water was very poor. Acetylene reduction activity in the nodules was found to be 70-90% and 50-70% after 12 and 24 months of preservation, respectively. The strains retained their phenotypic characters like antibiotic resistance and salt tolerance up to their highest survivability in respective nutritional condition.

Alkynes↗

PubMed1992

Mucosal calcified nodule. The oral counterpart of the subepidermal calcified nodule.

The subepidermal calcified nodule, also known as cutaneous calculi, is a form of idiopathic calcinosis that affects children and is occasionally present at birth. It occurs usually in the facial skin and has no relationship to connective tissue disease or to any abnormality in calcium or phosphorus metabolism. The oral cavity is very rarely affected by calcinosis cutis of any type, and idiopathic calcinosis has not been previously reported in the oral mucosa. This is a report of two cases of calcified nodules that occurred in the gingiva of a 1-year-old girl and the tongue of a 5-year-old boy. The lesions showed clinical, histologic, and histochemical similarities to the subepidermal calcified nodule. The name oral mucosal calcified nodule is proposed for this form of calcinosis.

Calcinosis↗

PubMed2005

Studies on manganese nodule leached residues 2. Adsorption of aqueous phosphate on manganese nodule leached residues.

Adsorption of phosphate onto manganese nodule leached residues was investigated as a possible alternative to conventional methods of phosphate removal from industrial effluents. Adsorption behaviors were studied as a function of time, temperature, pH, and concentration level of adsorbate and adsorbent in acetic acid-sodium acetate buffer medium. The adsorption of phosphate follows the Langmuir adsorption isotherms. The magnitude of adsorption of phosphate in manganese nodule leached residues was compared with that in naturally occurring Mn nodule. Manganese nodule leached residues show better affinity toward phosphate adsorption.

Adsorption↗

PubMed1990

Quelprud's nodule: a post-auricular cartilaginous nodule.

A number of minor variations to the configuration of the external ear are well recognized. This paper brings attention to one entity which is characterized by a small cartilaginous nodule or prominence arising from the posterior surface of the pinna and which we have named Quelprud's nodule. A prospective clinical survey of 208 patients attending an ENT clinic revealed that nearly one-third of the population studied possess this nodule. There was an equal sex incidence. The Quelprud's nodule was identified within families in a distribution which suggests an autosomal dominant inheritance with variable expressivity.

Adolescent↗

PubMed1983

Morphology of root nodules and nodule-like structures formed by Rhizobium and Agrobacterium strains containing a Rhizobium meliloti megaplasmid.

We examined expression of the megaplasmid pRme41b of Rhizobium meliloti in two different Rhizobium sp. Strains and in Agrobacterium tumefaciens. Transfer of pRme41b into these bacteria was facilitated by insertion of a recombinant plasmid coding for mobilization functions of RP4 into the nif region (Kondorosi, A., E. Kondorosi, C.E. Pankhurst, W. J. Broughton, and Z. Banfalvi, 1982, Mol. Gen. Genet., 188:433-439). In all cases, transconjugants formed nodule-like structures on the roots of Medicago sativa. These structures were largely composed of meristematic cells but they were not invaded by bacteria. Bacteria were found only within infection threads in root hairs, and within intercellular spaces of the outermost cells of the structures. The donor strain of R. meliloti containing pAK11 or pAK12 in pRme41b initially produced nodules on M. sativa that did not fix nitrogen (Fix-). In these nodules, bacteria were released from infection threads into the host cells but they did not multiply appreciably. Any bacteroids formed degenerated prematurely. In some cases, however, reversion to a Fix+ phenotype occurred after 4 to 6 wk. Bacteria released into newly infected cells in these nodules showed normal development into bacteriods.

Fabaceae↗

PubMed2003

Molecular cloning of the cDNA encoding aspartate aminotransferase from bean root nodules and determination of its role in nodule nitrogen metabolism.

A cDNA clone encoding aspartate aminotransferase (PVAAT-2) (EC 2.6.1.1) was isolated from the common bean Phaseolus vulgaris nodule cDNA library. The nucleotide sequence analysis of the full-length cDNA allowed its identification by comparison with sequence databases. The amino acid sequence of the bean PvAAT-2 showed high similarity with the AAT-2 isoforms described in other leguminous plants. The amino-terminal region of the PvAAT-2 contains a sequence, which shares common features of plastid transit peptides. Southern blot analysis showed that the PvAAT-2 clone is encoded by a single gene in the P. vulgaris genome. Analysis of the PvAAT-2 mRNA levels suggests that the expression of this gene is nodule enhanced. The PvAAT-2 transcript is more abundant in nodules with increased synthesis of amides and is down-regulated in conditions where ureides accumulate. When plants were supplemented with ureides or with amides, PvAAT-2 expression was reduced, while it was not affected when plants were treated with allopurinol, an inhibitor of ureide synthesis. On the other hand, the expression of asparagine synthetase (another enzyme involved in the synthesis of amides) is not affected either by ureides or amides. These data suggest a role for AAT-2 in the mechanism involved in the synthesis of nitrogen compounds in bean nodules.

Acetylene↗

PubMed1997

A nodule-specific gene family from Alnus glutinosa encodes glycine- and histidine-rich proteins expressed in the early stages of actinorhizal nodule development.

Two cDNAs representing different members (agNt84 and ag164) of a gene family encoding glycine- and histidine-rich proteins have been isolated from cDNA libraries from Alnus glutinosa root nodules. Expression of the corresponding genes could only be detected in nodules. With in situ hybridization, the expression in nodules was found to occur in young, infected cells of the prefixation zone (zone 2). The encoded proteins contain putative signal peptides for targeting to the endomembrane system, sharing sequence similarity with signal peptides from plant glycine-rich proteins, among them nodulin 24, a nodule-specific protein from soybean. This similarity suggests that, analogous to nodulin-24, proteins encoded by agNt84/ag164 may be located at the interface between the host plant membrane and the matrix surrounding the endosymbiont. The 3' untranslated regions of the cDNAs contain unusual poly(AT)n stretches that may play a role in the regulation of RNA stability. The protein encoded by agNt84 cDNA was expressed in Escherichia coli as a fusion with maltose-binding protein, and was shown to have the ability to bind to a nickel-chelating resin, indicating that it may function as a metal-binding protein.

Actinomycetales↗

PubMed1999

Nodule-inducing activity of synthetic Sinorhizobium meliloti nodulation factors and related lipo-chitooligosaccharides on alfalfa. Importance of the acyl chain structure.

Sinorhizobium meliloti nodulation factors (NFs) elicit a number of symbiotic responses in alfalfa (Medicago sativa) roots. Using a semiquantitative nodulation assay, we have shown that chemically synthesized NFs trigger nodule formation in the same range of concentrations (down to 10(-10) M) as natural NFs. The absence of O-sulfate or O-acetate substitutions resulted in a decrease in morphogenic activity of more than 100-fold and approximately 10-fold, respectively. To address the question of the influence of the structure of the N-acyl chain, we synthesized a series of sulfated tetrameric lipo-chitooligosaccharides (LCOs) having fatty acids of different lengths and with unsaturations either conjugated to the carbonyl group (2E) or located in the middle of the chain (9Z). A nonacylated, sulfated chitin tetramer was unable to elicit nodule formation. Acylation with short (C8) chains rendered the LCO active at 10(-7) M. The optimal chain length was C16, with the C16-LCO being more than 10-fold more active than the C12- and C18-LCOs. Unsaturations were important, and the diunsaturated 2E,9Z LCO was more active than the monounsaturated LCOs. We discuss different hypotheses for the role of the acyl chain in NF perception.

Carbohydrate Sequence↗

PubMed1981

Carbon Dioxide Fixation in Soybean Roots and Nodules: I. CHARACTERIZATION AND COMPARISON WITH N(2) FIXATION AND COMPOSITION OF XYLEM EXUDATE DURING EARLY NODULE DEVELOPMENT.

These studies demonstrate that soybean (Merr) roots and nodules possess an active system for fixing CO(2). The maximum rates of CO(2) fixation observed for roots and nodules of intact plants were 120 and 110 nanomoles CO(2) fixed per milligram dry weight per hour, respectively. Results of labeling studies suggest a primary role for phosphoenolpyruvate carboxylase in CO(2) assimilation in these tissues. After pulse-labeling with (14)CO(2) for 2 minutes, 70% of the total radioactivity was lost within 18 minutes via respiration and/or translocation out of nodules. During the vegetative stages of growth of soybeans grown symbiotically, CO(2) fixation in nodules increased at the onset of N(2) fixation but declined to a lower level prior to the decrease in N(2) fixation. This decrease coincided with a decrease in the transport of amino acids, especially asparagine, and an increase in the export of ureides. These findings are consistent with a dual role for CO(2) fixation, providing substrates for energy-yielding metabolism and supplying carbon skeletons for NH(4) (+) assimilation and amino acid biosynthesis.

Journal Article↗

PubMed1990

Heterogeneity of proliferative activity in nodule-in-nodule lesions of small hepatocellular carcinoma.

Surgically resected small hepatocellular carcinomas showing "nodule-in-nodule" formation were analyzed in terms of cell proliferative activity. The analysis was achieved by successful immunohistochemical demonstration of proliferating cell nuclear antigen in formalin-fixed paraffin-embedded tissue sections. Eight nodules (up to 3 cm in diameter) examined were either atypical adenomatous hyperplasia or hepatocellular carcinoma of low histologic grade, containing a discrete inner nodular area composed of obvious hepatocellular carcinoma of higher histologic grade. In all cases, the proliferating cell nuclear antigen labeling index of the latter area was much higher than that of the former, which in turn was slightly higher than that of the non-cancerous liver of the patient in 6 cases. The data presented here provide supporting evidence that the successive emergence and expansion of a more rapidly proliferating subclone within a nodule result in the stepwise progression of malignancy of human hepatocellular carcinoma.

Antigens, Neoplasm↗

PubMed1985

Characterization of Rhizobia from Ineffective Alfalfa Nodules: Ability to Nodulate Bean Plants [Phaseolus vulgaris (L.) Savi.].

This study was initiated to characterize Rhizobium isolates obtained from root nodules of ineffectively nodulated, field-grown alfalfa (Medicago sativa L.) plants. The purpose was to determine if these isolates possessed characteristics which would explain either their ineffectiveness in N(2) fixation or their apparent ability to tolerate the moderately acid soil conditions from which they originated. Isolates were characterized by analysis of growth rate, 39 degrees C tolerance, acid production on conventional media, and symbiotic performance. All isolates were ineffective in N(2) fixation on alfalfa, and they contained one or more anomalous characteristics. These included either slow growth rate, lack of 39 degrees C tolerance, or lack of acid production on conventional media. Infectiveness tests on a broad range of legumes revealed that the isolates formed root nodules on M. sativa, Medicago lupulina L., and Phaseolus vulgaris (L.) Savi. (common bean). These results provide evidence that, in some situations, ineffective nodulation of M. sativa in the field may be due to the presence of promiscuous, native Rhizobium species.

Journal Article↗

PubMed2005

Classification tool for the systematic histological assessment of hepatocellular carcinoma, macroregenerative nodules, and dysplastic nodules in cirrhotic liver.

AIM: To design a classification tool for the histological assessment of hepatocellular carcinoma (HCC), dysplastic nodules (DN), and macroregenerative nodules (MRN) in cirrhotic liver. METHODS: Two hundred and twelve hepatocellular nodules (106 HCC; 74 MRN; 32 DN) were assessed systematically, quantitatively, and semiquantitatively as appropriate for 10 histological features that have been described as helpful in distinguishing small HCC, DN, and MRN in cirrhotic livers. The data were analyzed by multiple correspondence analysis (MCA). RESULTS: MCA distributed HCC, DN, and MRN as defined by traditional histological evaluation as well as the individual histological variables, in a "malignancy scale". Based on the MCA data representation, we created a classification tool, which categorizes an individual nodular lesion as MRN, DN, or HCC based on the balance of all histological features (i.e., vascular invasion, capsular invasion, tumor necrosis, tumor heterogeneity, reticulin loss, capillarization of sinusoids, trabecular thickness, nuclear atypia, and mitotic activity). The classification tool classified most (83%) of a validation set of 47 nodules in the same way as the routine histological assessment. No discrepancies were present for DN and MRN between the routine histological assignment and the classification tool. Of 25 HCC assigned by routine assessment in the validation set, 8 were assigned to the DN category by the classification tool. CONCLUSION: We have designed a classification tool for the histological assessment of HCC and its putative precursors in cirrhotic liver. Application of this tool systematically records histological features of diagnostic importance in the evaluation of small HCC.

Carcinoma, Hepatocellular↗

PubMed2000

Ethylene is involved in the nodulation phenotype of Pisum sativum R50 (sym 16), a pleiotropic mutant that nodulates poorly and has pale green leaves.

R50 is characterized as a pleiotropic pea mutant; it forms few nodules and has short lateral roots, short stature and pale leaves. Using grafting techniques, R50 paleness was found to be controlled by the shoot of the mutant whereas the nodulation phenotype was regulated by its root. The paleness of R50 is due to a lower than normal total chlorophyll content in its young leaves. The defect appears to be overcome with age because, as the plant matures, the chlorophyll levels increase in the older leaves. The reduction in stature is attributed to shorter internodes, and the oldest internodes are thicker than those of the parent Sparkle. Upon rhizobial inoculation, R50 forms as many infection threads as Sparkle. However, most of these are arrested in the inner cortex. The threads appear to have lost their directional growth towards the stele, and they coil around within enlarged cortical cells. In addition, very few infection threads are associated with divisions of the inner cortical cells. These aborted nodule primordia are abnormal, flat and mainly composed of cells which have divided anticlinally only. Nodulation of R50 was restored by treating the roots with ethylene inhibitors. The R50 mutant further supports the postulated role of ethylene in regulating rhizobial infection with a probable role in the control of the primordium development.

Chlorophyll↗