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PubMed2003

Small pulmonary nodules: detection at chest CT and outcome.

PURPOSE: To determine the outcome of pulmonary nodules less than 1 cm in diameter detected at chest computed tomography (CT). MATERIALS AND METHODS: Reports of chest CT performed during 6 months were reviewed to find patients with pulmonary nodules smaller than 1 cm in long axis for which repeat CT was recommended. Records were studied to determine whether follow-up had been performed, the initial nodules had changed in size, or nodules had been resected. RESULTS: A total of 3,446 chest CT examinations were performed, with 334 patients meeting inclusion criteria. Three patients underwent nodule resection and had pathologic examination results positive for cancer; 185 underwent follow-up, of whom 13 had results excluded as indeterminate. In the remaining 172 patients, 88 had incomplete characterization because of follow-up of less than 2 years, which left 84 with nodule characterization at follow-up. When these 84 patients were combined with the three patients with nodule resection, the number yielded was 87 patients. Seventy-seven of 87 had benign nodules because of resolution or 2-year stability, and 10 of 87 had malignant nodules because of growth or positive histologic examination results. Nine of 10 with malignant nodules had a known primary neoplasm. CONCLUSION: CT commonly helped identify small nodules. Increase in size occurred infrequently and almost exclusively in patients with a known malignancy.

Adult↗

PubMed2004

Pulmonary nodules: preliminary experience with three-dimensional evaluation.

PURPOSE: To evaluate software designed to calculate pulmonary nodule volume in three dimensions. MATERIALS AND METHODS: Fifty-four solid noncalcified pulmonary nodules measuring 5-18 mm in diameter were studied with computed tomographic (CT) volumetric software. Baseline CT examinations were performed for various indications by using four-detector row multisection CT units, 1.25- or 2.50-mm sections, and a standard reconstruction algorithm. The percentage of successful nodule segmentations, as well as intraobserver variability, interreader agreement, and global repeatability of calculated volumes, was determined on the basis of consecutive measurements performed three times by three different radiologists by using the Bland and Altman method. The software was used to calculate the doubling time of 22 nodules for which a final diagnosis and comparable CT scans were available. RESULTS: Fifty-two (96%) of the 54 nodules were successfully segmented, allowing their volume to be calculated. Repeatability was high: There was no variation in the nine measurements of 35 (67%) of the 52 nodules. The coefficient of variation for the remaining 17 nodules (33%) was 2.26%. Bland and Altman 95% limits of acceptability, calculated on the basis of log-transformed data, yielded a maximum software measurement error of 6.38% of the previous volume measurement. Doubling time ranged from 4 to 188 years for the 13 benign nodules and from 37 to 216 days for the nine malignant nodules. CONCLUSION: Software volumetric analysis yielded repeatable estimates for 96% of the nodules examined. All software-calculated doubling times were in keeping with the benign or malignant nature of the nodules.

Adult↗

PubMed1999

Pulmonary nodules: experimental and clinical studies at low-dose CT.

PURPOSE: To compare the number of pulmonary nodules detected at helical low- and standard-dose computed tomography (CT) and to investigate the diagnostic value of low-dose CT with a radiation exposure equivalent to that used at chest radiography. MATERIALS AND METHODS: Two radiologists recorded pulmonary nodules at standard-dose (250 or 100 mA, pitch of 1; 200 mA, pitch of 2) or low-dose CT (50 or 25 mA, pitch of 1 or 2) in five postmortem specimens and 75 patients. Nodules were assessed by size (5 mm or smaller, 6-10 mm, or larger than 10 mm) and by diagnostic confidence ("definite nodule," "definite lesion, not classic nodule," or "questionable lesion, possibly representing a vessel") with the Wilcoxon signed rank test. Artifacts depicted at low-dose CT were recorded. RESULTS: There were no statistically significant differences in the number of nodules detected at standard- or low-dose CT except in nodules 5 mm or smaller that were assessed as definite nodules at standard- or low-dose CT (25 mA, pitch of 2) (472 vs 397, P < .05). Artifacts that possibly interfered with nodule detection were observed exclusively at CT with 25 mA and a pitch of 2. CONCLUSION: Pulmonary nodules were detected reliably at CT with 50 mA and pitch of 2 or with 25 mA and a pitch of 1. However, further reduction of the dose to that used at chest radiography was associated with a significant decrease in the number of nodules 5 mm or smaller that were detected, possibly due to artifacts.

Adult↗

PubMed2000

Dysplastic nodules in liver cirrhosis: evaluation of hemodynamics with CT during arterial portography and CT hepatic arteriography.

PURPOSE: To evaluate the portal and arterial blood supplies to dysplastic nodules in the cirrhotic liver with computed tomography (CT) during arterial portography (CTAP) and CT hepatic arteriography (CTHA). MATERIALS AND METHODS: Nineteen histopathologically proved low-grade dysplastic nodules and 13 high-grade dysplastic nodules in 17 patients with liver cirrhosis were evaluated with CTAP and CTHA for the presence of portal and arterial blood supplies to the nodules. The nodules ranged from 0.4 to 4.5 cm in diameter (mean, 1.6 cm). RESULTS: The portal supply was present in 14 of the 19 (74%) low-grade dysplastic nodules and in seven of the 13 (54%) high-grade dysplastic nodules. The hepatic arterial supply was increased in four of the 19 (21%) low-grade dysplastic nodules, present in nine (47%), and absent in six (32%). The arterial supply was increased in four of the 13 (31%) high-grade dysplastic nodules, present in four (31%), and absent in five (38%). CONCLUSION: The portal and arterial supplies to the low- and high-grade dysplastic nodules were variable and inconsistent. Therefore, it is difficult to detect and characterize the dysplastic nodules on the radiologic images on the basis of the blood supply.

Adult↗

PubMed1998

Clonal origin of toxic thyroid nodules with constitutively activating thyrotropin receptor mutations.

Constitutively activating TSH receptor mutations have recently been detected in toxic nodules. In vitro studies suggest that mutated receptor signaling constitutively elevates cAMP, which causes hyperfunction and proliferation of thyrocytes. Therefore, toxic nodules with constitutively activating somatic TSH receptor mutations should result from clonal expansion of a single mutated cell. To test this hypothesis, we studied the clonal origin of 27 toxic nodules. In 13 of 27 nodules, a somatic mutation in the TSH receptor was identified. A PCR-based clonality assay that analyzes X-chromosome inactivation was used. The assay amplifies a polymorphism located in the androgen receptor gene. Of 27 toxic nodules studied, 23 (85%) were informative for the polymorphism. In the group that contains a somatic mutation in the TSH receptor, 10 of 11 cases showed nonrandom X inactivation, indicating clonal expansion. In only one toxic nodule with a TSH receptor mutation was random X inactivation detected. In the group without detectable mutations in exons 9 and 10 of the TSH receptor and exons 7-10 of the Gs alpha protein, only 6 of 12 toxic nodules show nonrandom X-chromosome inactivation. Therefore, the majority of toxic nodules with constitutively activating TSH receptor mutations are of clonal origin. This finding supports the hypothesis that toxic nodules arise from aberrant growth of a single cell. It is widely accepted that somatic mutations might initiate monoclonal growth. The TSH receptor mutations in these toxic nodules together with Gs alpha mutations in others are the most likely candidates for the initiation of this thyroid tumor. The clonal origin of toxic nodules in the group without detected mutations in the TSH receptor or the Gs alpha protein suggests somatic mutations in genes that are unknown to date.

Female↗

PubMed2005

Real-time blood-pool images of contrast enhanced ultrasound with Definity in the detection of tumour nodules in the liver.

Lower mechanical index (MI) technique with newer microbubble agents has been introduced into clinical practice as a newer ultrasound (US) imaging. However, the efficacy in detecting tumour nodules has not been proven scientifically. The aim of this study was to elucidate the efficacy of a blood-pool image of real-time contrast-enhanced US under low MI in detecting liver tumours. 15 rabbits with VX-2 tumour were used; the number of implantations was none in two rabbits, one in four, two in five and three in four. US equipment was APLIO (Toshiba) with linear probe (3.5/7.0 MHz). The number, location and size of tumour nodules were examined by non-contrast tissue harmonic imaging (NC-US) or contrast-enhanced pulse subtraction harmonic imaging (C-US) under extra-low MI (MI 0.065) with the injection of Definity (30 microl kg(-1)). The number of tumour nodules detected by both NC-US and C-US were consistent with the histopathological results in five rabbits - two with none, two with one nodule and one with two nodules. In the other 10 rabbits, C-US showed all the implanted tumours and small daughter nodules around them that were confirmed by histopathology. However, NC-US failed to demonstrate two implanted nodules and all the daughter nodules. On the basis of the histopathological results, detectability of implanted tumour was not significantly different between NC-US (24/26, 92.3%) and C-US (26/26, 100%). However C-US was superior to NC-US in delineating the nodules and in detecting small daughter nodules. The sizes of the implanted tumour nodules measured by histopathology correlated closely with those measured by C-US. Real-time blood-pool images by pulse subtraction harmonic imaging under extra-low MI with Definity will contribute to the improvement of the ultrasound delineation and detection of liver tumours.

Animals↗

PubMed1990

On the usefulness of levothyroxine suppressive therapy in the medical treatment of benign solitary, solid or predominantly solid, thyroid nodules.

The efficacy of levothyroxine suppressive therapy in the treatment of benign solitary thyroid nodules is controversial. In order to investigate this issue further we studied 122 patients with a solitary, solid or predominantly solid, thyroid nodule. The benign (colloid) nature of all nodules was proved by fine-needle aspiration biopsy. At the pertechnetate-99m thyroid scanning 91% of the nodules were "cold" and 9% "warm". All the patients received suppressive oral doses of levothyroxine (0.1 to 0.2 mg/day). Fifty-three patients were treated with levothyroxine for 6 months, 31 for 9 months and 38 for 12 months. The size of each nodule before and after treatment was evaluated by high-resolution ultrasonography. The actual suppression of TSH secretion was monitored at 3-month intervals using an ultrasensitive immunometric assay. At the end of levothyroxine treatment, patients were classified as responders (decrease in nodule volume greater than or equal to 50%, 68/122 = 55.7%; mean percent change in nodule volume = -77.1 +/- 15.7%), partially responders (decrease in nodule volume less than 50%, 24/122 = 19.7%; mean percent change in nodule volume = -27.5 +/- 10.1%), and nonresponders, when either no change in nodule volume (16/122 = 13.1%) or an increase in nodule volume (14/122 = 11.5%) was observed. In each group serum free T4 rose significantly in response to levothyroxine therapy, whereas serum free T3 remained unchanged. TSH levels were undetectable in all patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed2006

Inherent variability of CT lung nodule measurements in vivo using semiautomated volumetric measurements.

OBJECTIVE: The objective of our study was to evaluate repeatability and reproducibility of lung nodule volume measurements using volumetric nodule-sizing software. MATERIALS AND METHODS: Fifty nodules, less than 20 mm in diameter, in 29 patients were scanned with 1.25-mm collimation using MDCT (time 1 = T1). During the same session, two additional scans, using identical technique, were obtained through each nodule (T2, T3). Three observers working independently then obtained volumetric measurements using a semiautomated volumetric nodule-sizing software package. Qualitative nodule characterization was also performed. The Bland-Altman method for assessing measurement agreement was used to calculate the 95% limits for agreement for nodule volumes at T1, T2, and T3. RESULTS: Automated nodule segmentation was successful in 438 (97%) of 450 measurements. Forty-three nodules were available for final evaluation. Twenty-six nodules had well-defined edges, and 17 had irregular or spiculated margins. Seventeen were freestanding, 16 were juxtapleural, and 10 were juxtavascular in location. Average nodule volume was 345.5 mm(3) (range, 49.3-1,434 mm(3)). The mean interobserver variability (repeatability) was 0.018% (SD = 0.73%), and the SD of the mean for the three contemporaneous scans (reproducibility) was 13.1% (confidence limits, +/- 25.6%). SD and confidence limits narrowed as volumes increased. CONCLUSION: Volumetric measurements show minimal interobserver variability (0.018%) but an interscan SEM of 13.1% (confidence limits, +/- 25.6%). Repeatability and reproducibility of volumetric measurements are better than those of linear measurements reported in the literature.

Adult↗

PubMed1993

Localization of peripheral pulmonary nodules for thoracoscopic excision: value of CT-guided wire placement.

OBJECTIVE: One of the indications for the rapidly expanding use of thoracoscopic surgery as an alternative to thoracotomy is the excision of peripheral lung nodules. Nodules judged too small or too far from the pleural surface to be seen or palpated during thoracoscopy must be localized beforehand. The purpose of this study was to evaluate the feasibility and effectiveness of percutaneous placement of spring hookwires to localize such nodules before video-assisted thoracoscopy. SUBJECTS AND METHODS: Under CT guidance, 17 nodules in 14 patients were preoperatively localized with the Kopans breast lesion localization system. Three patients who had solitary nodules had thoracoscopic resections for diagnosis because a previous transthoracic needle or transbronchial biopsy had been unsuccessful. Four patients who had lesions less than 8 mm in diameter had thoracoscopic biopsies because transthoracic fine-needle aspiration biopsy was not likely to be diagnostic. Seven patients, who had a total of 10 nodules, had therapeutic wedge resections of either limited metastases or a second bronchogenic carcinoma. Mean nodule diameter was 10 mm (range, 3-20 mm). The mean distance from nodule to costal pleura was 9 mm (range, 0-25 mm). At the end of the procedure, wire placement was confirmed by CT scanning. After thoracoscopy, the surgeons were questioned about the stability and utility of each hookwire localization. RESULTS: In all 17 procedures, a hookwire was placed successfully. In one case, the wire dislodged before thoracoscopy (after a 6-hr preoperative delay and severe bending of the wire during induction of anesthesia). In 16 of the 17 resections, the surgeon thought that thoracoscopic identification of the lesion would not have been possible without hookwire localization. Only one localization, across a major fissure, required placement of a second wire to localize a nodule. Wire-related complications included two instances of serious pain, five cases of clinically insignificant pneumothorax, and one large pneumothorax requiring drainage before a second nodule in the same lung was localized. CT scanning showed presumed local pulmonary hemorrhage in six cases without hemoptysis or hemothorax. CONCLUSION: CT-guided hookwire localization is easily and safely performed and permits thoracoscopic resection of lung nodules, which might otherwise be impossible.

Adult↗

PubMed2000

Identification of feeding arteries to establish the intra- or extraparotid location of jugulodigastric nodules: value of color Doppler sonography.

OBJECTIVE: The objective of our study was to determine the value of color Doppler imaging as an adjunct to gray-scale sonography to reveal the intra- or extraparotid origin of jugulodigastric nodules of uncertain location. SUBJECTS AND METHODS: Forty nodules in the jugulodigastric area from 38 patients were imaged with gray-scale, color, and power Doppler sonography. Nodules receiving vessels from salivary glands were assumed to be intraglandular; those accepting vessels from paraparotid spaces were considered to arise from outside the gland. Imaging results were correlated with biopsy and surgical findings. RESULTS: In 38 of 40 cases, color and power Doppler sonography displayed discrete feeding arteries leading to the nodules: 25 nodules had one supplying artery, nine received two arteries, and four had three or more arteries. Intraparotid nodules received vessels from the gland in 20 cases. In two cases, the source of vessels was indeterminate. In two malignant tumors, multiple arteries derived from both the parotid and the neck spaces. All 14 extraparotid nodules received the arterial supply from paraparotid spaces. Color Doppler sonography enabled prediction of the intraglandular location of the nodules in 91% of cases and the extraglandular location in 87.5% of cases. The correct diagnosis was achieved in 34 of 40 nodules, with a global accuracy of 85%. CONCLUSION: Color Doppler sonography can help to assess the intra- or extraparotid location of jugulodigastric nodules. In practice, this technique can support the diagnosis when gray-scale sonography raises doubts about the origin of a jugulodigastric nodule.

Adenolymphoma↗

PubMedDate not supplied

Small hepatocellular carcinoma with minute satellite nodules.

BACKGROUND/AIMS: To investigate the clinicopathologic characteristics of small hepatocellular carcinoma with minute satellite nodules. METHODOLOGY: We investigated the clinicopathologic characteristics of 131 solitary small (< or = 2.0 cm in diameter) hepatocellular carcinomas including 105 hepatocellular carcinomas without minute satellite nodules and 17 hepatocellular carcinomas with minute satellite nodules smaller than 5 mm, and also discuss the clinical significance. RESULTS: None of the clinical backgrounds of the patients and pathologic features of the main tumor, except for the average of preoperative serum alpha-fetoprotein, were significantly different between the two groups. Firstly, minute satellite nodules demonstrated that the maximum diameter of all minute satellite nodules was 1.5-4.0 mm, secondly, the moderately to poorly differentiated hepatocellular carcinomas had 4 or more minute satellite nodules within 1 cm from the main tumor, while well differentiated hepatocellular carcinomas may have 1 or 2 minute satellite nodules 6 cm or more away, and thirdly, 4 or more minute satellite nodules may present within 1 cm in intrahepatic metastasis cases, while 1 or 2 minute satellite nodules may be present 6 cm or more away from the main tumor in multicentric occurrence cases. CONCLUSIONS: At least 13% of solitary small hepatocellular carcinomas had preoperatively undetectable minute satellite nodules. In case of moderately to poorly differentiated hepatocellular carcinomas, hepatic resection as well as percutaneous ethanol injection should be performed including the surrounding liver tissue at least 1.0 cm from the main nodule. On the other hand, in well-differentiated hepatocellular carcinomas, which may indicate multicentric occurrence, closer observation and careful follow-up after therapy are recommended.

Carcinoma, Hepatocellular↗

PubMed1975

Hormone dependence and estradiol receptors in the D series of mammary nodule outgrowth lines and tumors.

Preneoplastic mammary nodule outgrowth lines were examined for their ability to grow and produce tumors in ovariectomized BALB/c mice. In addition, these nodule outgrowth lines and tumors derived from them were investigated for cytoplasmic estrogen receptor proteins by qualitative and quantitative techniques. Early ovariectomy, performed within 4 weeks after transplantation, slightly delayed but did not permanently block the ability of three different nodule lines to completely fill the fat pad with nodule tissue. Ovariectomy performed later than 4 weeks after transplantation or adrenalectomy performed early or late had no effect on nodule growth. Neither early nor late ovariectomy or adrenalectomy had an effect on the maintenance of the nodule alveolar phenotype. Ovariectomy performed 3 weeks after transplantation had little effect on the tumor potential of the low oncogenic line D1 or the high oncogenic line D2. Samples of nodule outgrowths transplanted from ovariectomized mice responded to a chemical carcinogen in a similar manner, as did nodule outgrowths transplanted from control experiments. Thus, the altered hormonal environmenment in ovariectomized mice apparently did not select for subpopulations of nodule cells with altered tumorigenic potentials. The ovarian independence of the nodule lines and tumors derived from them was correlated with a very low level of cytoplasmic estrogen receptor. These results, along with other data, illustrate the nature of the independence on ovarian hormonal control for tumorigenesis in these mammary tumor virus-free nodule lines.

9,10-Dimethyl-1,2-benzanthracene↗

PubMed1991

Use of an ophthalmologic ultrasoundscanner in human onchocercal skin nodules for non-invasive sequential assessment during a macrofilaricidal trial with amocarzine in Guatemala. The first experiences.

Ultrasonography of onchocercal skin nodules was performed with an ophthalmologic real time linear scanner with a B probe of 10 MHz. A clinical trial in Guatemala with amocarzine (CGP 6140)--a new oral macrofilaricidal compound--investigated three repeat dose regimens and one placebo control group, each group consisting of six patients. Onchocercal nodules were scanned before treatment and on day 10, 30 and 60 after start of amocarzine. A total of 28 treated and 8 additional untreated nodules were analysed and compared with the histologic findings following nodulectomy at day 60. Of the 28 treated nodules, 21 were of onchocercal origin and seven were lymph nodes. The correlation between ultrasonography and histology was good in 25 patients, but did not match in three. In 20 out of 21 treated nodules a progressive ultrasonographic change over two months was seen. Of the eight additional untreated nodules, five were of onchocercal origin, one was a lymph node, one an epidermoid cyst and in one only fibrous tissue was detected. The ultrasonography correlated well to histology in seven nodules but not in one. In five onchocercal nodules no change was observed over two months. For initial control purposes six nodules were excised around day 10, four were of onchocercal origin and two were lymph nodes. The correlation was good in four. The present results indicate that an ophthalmologic real time linear scanner can be used in the bidimensional mode as a non-invasive method to assess sequentially the events in superficial onchocercal nodules following chemotherapy with amocarzine. This is the first objective non-invasive method permitting sequential assessment of the content of onchocercal nodules and it is far superior than subjective sequential manual palpation.

Animals↗

PubMed1989

State of hepatitis B viral genomes in cirrhotic and hepatocellular carcinoma nodules.

DNA of individual cirrhotic nodules (CN) and hepatocellular carcinoma nodules (HCN) of three hepatitis B surface antigen positive autopsy cases with macronodular cirrhosis were analyzed by Southern blot and slot blot hybridization with a hepatitis B virus (HBV) DNA probe. Evidence of episomal or replicating viral DNA, viral DNA integration at the same cellular DNA site in many cells (clonal integration) and viral integration in different cellular DNA sites in many different cells (non-clonal integration) was found in different cirrhotic nodules of the same liver, indicating heterogeneity in the state of HBV in different cells and in different cirrhotic nodules within each infected liver. Episomal or replicating viral DNA forms were found in all cirrhotic nodules of one liver, in less than 10% of examined nodules of a second liver and in none of the third. Evidence of clonal viral integration was found in CN of all three livers and non-clonal integration in CN of the latter two. Cirrhotic nodules with apparent different integrations in many different cells (non-clonal integration) outnumbered those with the same integration site in many cells (clonal integration), and many cirrhotic nodules in those two livers had no detectable viral DNA. Cirrhotic nodules with a viral integration in the same cellular DNA site in many cells would appear to have been formed by clonal expansion of an original cell containing the viral integration, and cirrhotic nodules with different integrations in many different cells (non-clonal integration) may have been formed by recruitment of many different cells with different viral integrations or by clonal expansion of cells without HBV integrations and subsequent viral integrations occurring integration. In one liver, three different hepatocellular carcinoma nodules appeared to represent metastatic lesions because the clonal pattern of HBV integration was identical in each, and in another liver different HCN appeared to be of different clonal origin, i.e. to have arisen from different cells, because multiple viral integrations (i.e. multiple individual restriction fragments with HBV sequences) were each different in different HCN of that liver.

Blotting, Southern↗

PubMed1989

[Subpopulations of lymphocytes in onchocercal nodules].

Fourty onchocercal nodules were taken from patients living in forest areas where onchocerciasis is highly endemic, in order to identify the various types of lymphocytes present in these nodules. For this purpose, each nodule was submitted to two histological procedures: one after fixation in formalin of part of the nodule and hematoxylin-eosin stain; the other after freezing part of the nodule in liquid nitrogen, cryostat cutting and staining by immuno-peroxidase method using avidin-biotin and the following monoclonal antibodies: Pan B, OK T3, OK T4 and OK T8. Fifty-five of the 40 nodules show lymphocytes. All the 25 nodules with lymphocytes present T-lymphocytes. Only 20 of these 25 nodules have B lymphocytes and therefore only 20 nodules with lymphocytes have both T and B lymphocytes. Of the 25 nodules with T lymphocytes: 19 present T4 lymphocytes, 25 show T8 lymphocytes and therefore 19 have both T4 and T8 lymphocytes. These results are analysed and discussed in this study which notices that there is an intense cellular and humoral immune reaction in onchocercal nodules, an insufficient reaction as parasitic antigens persist and are not destroyed.

Humans↗

PubMed1989

[Utilization of nitrate by bacteroids and cytosol of nodules formed by Rhizobium leguminosarum].

Nitrite production by nodules and roots of pea plants (Pisum sativum L., cultivar Alaska) inoculated with Rhizobium leguminosarum strain 3855 has been studied. Nitrate reductase (NR) activity and nitrite reductase (NiR) activity of the bacteroidal and cytosolic fractions of the nodules were also determined, as well as the nitrite content of the nodules cytosol. Nitrite production by nodules and roots from plants treated with 5 mM KNO3 was higher than that of nodules and roots from plants not treated with nitrate, and regardless of the nitrate treatment, nitrite production increased with the incubation period. The presence of nitrate, propanol or both compounds in the incubation mixtures significantly increased the nitrite production by nodules and roots. Nitrite reductase activity was detected in fresh by isolated bacteroids of R. leguminosarum strain 3855, although the presence of nitrate reductase activity could not be detected both in bacteroids of nodules isolated from plants treated or not with 5 mM KNO3. After isolation, when bacteroids were incubated in a mixture with nitrate, nitrate reductase activity developed after incubation for 12 h. Consequently, there was an increase in nitrite reductase activity, which resulted in the disappearance of the nitrite previously accumulated in the incubation medium. Nitrate utilization by bacteroids was not detected until 5 h from the beginning of the incubation period. Since the presence of chloramphenicol or rifampicin in the incubation medium prevented the development of the nitrate reductase activity, such activity was induced in bacteroids. Nitrite content and nitrate reductase and nitrite reductase activities of the cytosol from nodules of pea plants treated or not with 5 mM KNO3 varied with the buffer used for nodules homogenization. However, no nitrite was found when nodules were homogenized with ethanol, what indicates that nitrite accumulation in the cytosol occurs during the homogenization process of the nodules.

Bacterial Proteins↗

PubMed1989

Carcinoma of the lung. Evaluation of satellite nodules as a factor influencing prognosis after resection.

Satellite nodules are considered to be predictive of poor prognosis in breast cancer and in melanoma. In lung cancer, there is no information as to their definition, prevalence, or implication as a prognosis factor of survival after resection. Over the past 18 years (1969 to 1987), 84 patients underwent pulmonary resection for primary lung cancer accompanied by satellite nodules. These nodules were defined as well-circumscribed accessory carcinoma foci clearly separated from the main tumor but with identical histologic characteristics. All were smaller than the primary carcinoma and most were located within the same lobe. Survival rates of patients with satellite nodules were compared to those of 1021 patients without satellite nodules who underwent resection during the same time interval. The 1-, 3-, and 5-year survival rates for all patients classified as having no satellite nodules were 78%, 54%, and 44%, respectively, and the median survival for the entire group was 30 months. In patients with satellite nodules, these survival rates were 60.9%, 32.7%, and 21.6%, respectively, with a median survival of 15 months. The deleterious effect of satellite nodules was more significant in patients with stage I disease (p = 0.0008) than in patients with stage II (p = 0.0354) or stage III (p = 0.0145) disease. Survival data obtained by comparison of satellite nodule status and histologic characteristics shows that 5-year survival figures are better for patients with no satellite nodules in both the squamous and the nonsquamous groups. This study demonstrates that satellite nodules associated with lung cancer are indicative of locally advanced and/or premetastatic disease. These patients should be included in the stage group IIIa of the TNM stage grouping classification.

Adult↗

PubMed1985

Microcirculation of hepatic nodules from diethylnitrosamine-treated rats.

The microcirculation of nodules (0.5 to 10 mm in diameter) from diethylnitrosamine-treated rats was studied in perfused livers. Microlight guides were placed on nodules and surrounding tissue on the capsular surface of the liver to measure fluorescence due to fluorescein-dextran (12 microM), a dye confined to the vascular space, infused via the hepatic artery and portal vein separately or simultaneously. The fluorescence increase due to fluorescein-dextran infusion via the artery and vein simultaneously was used to compare vascular space in nodules with that of surrounding tissue. The vascular space of nodules less than 1 mm in diameter was only about one-half as large as that of surrounding tissue. In contrast, in nodules 1 to 2 mm in diameter, the vascular space was similar to values from surrounding tissue. This was largely due to an increase in the fluid entering via the artery. As nodules grew from 2 to 10 mm in diameter, the vascular space decreased as a function of nodule size to 40% of surrounding tissue. The sum of fluorescence increases due to fluorescein-dextran infused via the artery and vein separately always equalled values obtained from simultaneous infusions. From these measurements, the fraction of vascular fluid observed by the microlight guide that entered the liver via the artery was calculated. In tissue surrounding nodules, fluid entering from the artery was 19% of the total, a value approximating the fraction of fluid pumped into the liver via the artery (25%). The percentage of fluid in the nodule that entered the liver via the hepatic artery increased progressively to 100% of the total as nodules grew from 2 to 10 mm in diameter. Thus, nodules become increasingly dependent on the hepatic artery and less dependent on blood supply via the portal vein as they grow.

Animals↗