Increase In Size Of Nodes Research Articles

Nodule size is an independent predictor of malignancy in mutation-negative nodules with follicular lesion of undetermined significance cytology

In thyroid nodule fine-needle aspiration (FNA) cytology, the atypia of undetermined significance or follicular lesion of undetermined significance (AUS/FLUS) category has a 5-15% malignancy risk that increases to 85-99% when mutation testing for BRAF, RAS, RET/PTC, or PAX8/PPARγ is positive. However, negative testing does not exclude malignancy. The study objective was to identify clinical and imaging features that predict cancer in mutation-negative AUS/FLUS thyroid nodules. All patients were reviewed (April 2007 to April 2009) who had AUS/FLUS cytology, negative prospective molecular testing of FNA, and histopathology. Of the 230 nodules, 12 (5.2%) were malignant in 11 of 190 patients, and known clinical risk factors for thyroid cancer did not predict malignancy. On preoperative imaging, ≥1 suspicious ultrasound feature was identified in 33% of nodules and occurred regardless of histology (P = .23). Malignant mutation-negative AUS/FLUS nodules were larger than benign nodules (mean maximum diameter, 33.6 vs 24.0 mm; P = .007). On multivariate analysis, nodule size remained an independent predictor of malignancy (odds ratio, 1.043; P = .018). We observed no malignancies in 88 mutation-negative AUS/FLUS nodules <18.5 mm. Size is an independent predictor of malignancy in mutation-negative AUS/FLUS nodules and the risk increased 4.3% with every millimeter increase in nodule size. Selected patients with small, mutation-negative AUS/FLUS thyroid nodules may be managed with ultrasound surveillance in lieu of thyroidectomy.

Erratum to: Gentamicin Reduces Calcific Nodule Formation by Aortic Valve Interstitial Cells In Vitro

For the ARS assay, there was a significant reduction in the number of nodules with every increasing concentration of gentamicin. In addition, there was a significant increase in the average size per nodule for the 0.1 and 0.2 mM gentamicin groups compared to control (representative nodules shown in Figs. 1a, 1b). The overall decrease in nodule number and increase in nodule size from the control group to the 0.2 mM gentamicin group was 49 and 57%, respectively (Figs. 2a, 2b). The total calcified area was significantly reduced for the 0.05, 0.1, and 0.2 mM gentamicin groups, resulting in 21% less calcified area at the highest gentamicin concentration of 0.2 mM compared to control (Fig. 2c). Similar to the ARS assay, the von Kossa staining showed a significant decrease in nodule number at every increasing concentration of gentamicin and a significant increase in nodule size for the 0.1 and 0.2 mM gentamicin groups compared to control (data not shown; representative nodules shown in Figs. 1c– 1d). The overall decrease in nodule number and increase in nodule size from the control group to the 0.2 mM gentamicin group was 47 and 51%, respectively. The total calcified area also decreased with gentamicin concentration, with the 0.2 mM gentamicin group having 20% less calcified area than the control group (Fig. 3a). The same pattern was shown by the alkaline phosphatase assay, with the 0.2 mM gentamicin group having 49% less alkaline phosphatase compared to control (Fig. 3b). For both von Kossa total calcified area and the alkaline phosphatase assay, the 0.1 and 0.2 mM gentamicin groups were significantly different from controls.

Thyroid surgery – intraoperative localization and protection of important structures of the neck

Nodular thyroid disease affects 500 to 600 million people worldwide. Tumours of the thyroid account for about 1% overall human cancers. Thyroidectomy is the most common endocrine operation. Surgical treatment for benign thyroid nodules is recommended for: progressive increase in nodule size, substernal extension, compressive symptoms in the neck region, the development of thyrotoxicosis and in case of preference of that kind of treatment reported by the patient. In Poland thyroidectomy is the fourth surgical procedure and concerns 25000 operations yearly. Reduction of surgical injury with simultaneous retention of current safety and radical nature of surgical procedure forces the work in a relatively small operating field. Electric devices enabling the achievement of full and lasting haemostasis during thyroidectomy supplant traditional surgical method (ligature, haemostatic sutures) with no impact on the incidence of perioperative complications, while at the same time allowing to shorten the duration of the procedure. The haemostatic effect is associated with generation of heat, which apart from the intended result may bring about thermal tissue injury. During the surgical procedure important is to determine the thermal spread around the active tip of electric devices in the operating field during thyroidectomy, and the safe temperature range during the operation to protect important structures of the neck. The mean safe distance of the active tip of an electric device from important anatomic structures is 5mm minimally and depends on the device type, time of using and its power settings. All the modern techniques of vessel sealing are associated with generation of heat and its spherical spread, which causes thermal injury to the surrounding tissues. Their mode of operation through, among others, structural changes in collagen and elastin, leads to lasting joining of sealed vessel walls and tissue structures. These systems enable a safe sealing of vessels of up to 7mm in diameter. In conclusions: In the cases analysed by the author concerning the thyroidectomy techniques, it is recommended to replace to electric devices with ligatures or clips or human fibrinogen in place near the laryngeal nerves, parathyroid glands and the trachea. The decision on the change of the method of haemostasis maintenance in the vicinity of crucial structures belongs to the surgeon.

Network load and traffic pattern on the capacity of wireless ad hoc networks

This paper focuses on the capacity of wireless ad hoc networks and analyzes the effect of key factors viz. network size, traffic patterns and detailed local radio interactions on the capacity of such networks. The capacity is evaluated with several different network layouts and traffic patterns through simulations. To demonstrate the impact of these factors, the capacity evaluation starts with a simple case of a chain of evenly spaced nodes in a network environment and progresses to a network with random traffic and randomly spaced nodes. Initially, capacity of static nodes is evaluated for various network layouts and traffic patterns. Since, in most scenarios, nodes do not travel significant distances during packet transmissions. As an enhancement, mobility of nodes is introduced into the network scenario and the performance is again evaluated. The simulations are carried out using OPNET modeler and the results obtained are presented in this report. The results are analyzed to understand the impact of these factors on the capacity and consequently suggest measures to increase the same. This work shows that the achievable capacity of ad hoc network depends on network size, traffic pattern and mobility. In a single cell topology, it is found that there is a 50% reduction in network throughput, if the node size increases from 2 to 10 nodes, whereas there is a 74% reduction in the throughput for chain topology for the same increase in node size. In a lattice topology with horizontal traffic, there is a 46 % reduction in network throughput when the lattice size increases from 4X4 to 5x5.The same percentage of reduction is observed when both horizontal and network traffic is introduced. In a random network topology with random traffic, there is an 80 % reduction in network throughput when the node size increases from 150 to 750 nodes. However, for the same scenario with the introduction of mobility to the nodes, a slight improvement is achieved with an overall 75% reduction in network throughput.

Squamosal ontogeny and variation in the pachycephalosaurian dinosaur Stegoceras validum Lambe, 1902, from the Dinosaur Park Formation, Alberta

ABSTRACT The pachycephalosaurian squamosal is one of the most diagnostic bones in this enigmatic group of dinosaurs, but little is known about variation in its morphology. Despite this, features of squamosal morphology are often used in diagnoses and phylogenetic studies. The recently proposed hypothesis of an ontogenetic transition from Dracorex to Pachycephalosaurus implies a large amount of ontogenetic variation in squamosal ornamentation that has not been well documented due to the small number of squamosals for these taxa. Stegoceras validum provides an important model for examining variation in squamosal morphology due to the large number of squamosals available. Here we examine the morphology of 14 S. validum squamosals both qualitatively and quantitatively. We find that although both node number and shape vary considerably, there is no clear ontogenetic pattern, which suggests a high degree of individual variation. The ornamental pattern, however, is maintained throughout the sample. Increase in node size is isometric for the enlarged medial node and normal posterior nodes, but negatively allometric for the vertex node. The squamosal bar is taller laterally than medially in nearly all specimens and increases in height with positive allometry at the same rate medially and laterally. We found no correlation between the width of the supratemporal fenestra on the squamosal and the size of the squamosal itself. Rather, this feature appears to exhibit a large degree of individual variation. Overall, these findings have implications for previous hypotheses of ontogenetic growth and function of the ornamentation, as well as the construction of phylogenetic characters.

Ultrasound-Guided Percutaneous Thyroid Nodule Core Biopsy: Clinical Utility in Patients with Prior Nondiagnostic Fine-Needle Aspirate

Five percent to 20% of thyroid nodule fine-needle aspiration (FNA) samples are nondiagnostic. The objective of this study was to determine whether a combination of FNA and core biopsy (CFNACB) would yield a higher proportion of diagnostic readings compared with FNA alone in patients with a history of one or more prior nondiagnostic FNA readings. We conducted a retrospective study of 90 core biopsies (CBs) performed in 82 subjects (55 women and 27 men) between 2006 and 2008 in an outpatient clinic. CFNACB yielded a diagnostic reading in 87%. The diagnostic reading yield of the CB component of CFNACB was significantly superior to the concurrent FNA component, with CB yielding a diagnosis in 77% of cases and FNA yielding a diagnosis in 47% (p<0.0001). The combination of CB and FNA had a higher diagnostic reading yield than either alone. In 69 nodules that had only one prior nondiagnostic FNA, CB was diagnostic in 74%, FNA was diagnostic in 52%, CFNACB was diagnostic in 87%, and CB performed significantly better than FNA (p=0.0135). In 21 nodules with two or more prior nondiagnostic FNAs, CFNACB and CB were diagnostic in 86%, FNA was diagnostic in 29%, and CB was significantly better than FNA (p=0.0005). Clinical, ultrasound, or histopathologic follow-up was available for 81% (73/90) of the CFNACB procedures. No subject with a benign CFNACB reading was diagnosed with thyroid malignancy in the follow-up period (range 4-37 months, mean 18 months), although one subject had minimal increase in nodule size and was awaiting repeat sonography at study conclusion. Thyroid nodule CFNACB is safe and clinically useful in selected patients when a prior FNA reading is nondiagnostic. CFNACB is superior to either CB or FNA alone. CFNACB should be strongly considered as an alternative to surgery in individuals with two prior nondiagnostic FNAs.

Hypothyroidism, new nodule formation and increase in nodule size in patients who have undergone hemithyroidectomy

IntroductionThe current medical literature has conflicting results about factors related to hypothyroidism and nodular recurrences during follow-up of hemithyroidectomized patients. We aimed to evaluate factors that may have a role in new nodule formation, hypothyroidism, increase in thyroid lobe and increase in nodule volumes in these patients with and without Hashimoto's thyroiditis (HT), and with and without levothyroxine (LT4) use.Material and methodsWe enrolled 140 patients from five different hospitals in Ankara and evaluated their thyroid tests, autoantibody titre results and ultrasonographic findings longitudinally between two visits with a minimum 6-month interval.ResultsIn patients with HT there was no significant difference between the two visits but in patients without HT, thyroid stimulating hormone (TSH) levels and nodule volume were higher, and free T4 levels were lower in the second visit. Similarly, in patients with LT4 treatment there was no difference in TSH, free T4 levels, or lobe or nodule size between the two visits, but the patients without LT4 had free T4 levels lower in the second visit. Regression analysis revealed a relationship between first visit TSH levels and hypothyroidism during follow-up.ConclusionsPatients who have undergone hemithyroidectomy without LT4 treatment and without HT diagnosis should be followed up more carefully for thyroid tests, new nodule formation and increase in nodule size. The TSH levels at the beginning of the follow-up may be helpful to estimate hypothyroidism in hemithyroidectomized patients.

Efficiency of Ultrasound and Ultrasound-Guided Fine Needle Aspiration Cytology in Preoperative Assessment of Axillary Lymph Node Metastases in Breast Cancer

PurposeWe performed this study to detect preoperative axillary metastases with ultrasound (US)-guided fine needle aspiration biopsy (FNAB), to eliminate the need for time-consuming and costly sentinel lymph node (SLN) scintigraphy and biopsy steps in the treatment of breast cancer patients, and in that of with suspicious US findings, and to evaluate the accuracy of preoperative US-guided FNAB for patients with suspicious lymph node metastases on US.MethodsPatients with a suspicious breast lump or histopathologically proven breast cancer underwent breast-axillary US. Increase in lymph node size, cortical thickening, non-hilar cortical flow, and hilar changes were evaluated with gray scale-color Doppler US. FNAB was performed if US results were suspicious for malignancy.ResultsThirty-eight axillary lymph nodes (ALN) underwent FNAB. ALN dissection, SLN scintigraphy, and biopsy steps were bypassed in 23 axillas with positive ALN FNAB (60.5%). The sensitivity of ALN FNAB was 88.46%; specificity and positive predictive value were 100%; and negative predictive value was 66.6% (inadequate cytology included; 76.7%, 100%, 100%, 53.3%, respectively). Asymmetrical cortical thickening, non-hilar cortical flow, and increase in hypoechogenity were only detected in metastatic nodes. Cortical thickening, and lymph node and breast mass size was higher in the metastatic group.ConclusionBy performing FNAB on suspicious lymph nodes, the routine, high-cost SLN scintigraphy and intraoperative gamma probe steps may be skipped, and axilla dissection can be performed directly. This leads to the elimination of the need for SLN investigation in more than half of the patients. The assessment of ALN metastases with preoperative US-guided FNAB is a cost-effective method with high specificity, that eliminates the need for costly and time-consuming SLN scintigraphy and biopsy steps, and helps in preoperative staging.

Reversible Locoregional Lymph Node Enlargement After Radiofrequency Ablation of Lung Tumors

The objective of our study was to assess the characteristics of locoregional lymph node enlargement after successful radiofrequency ablation (RFA) in the treatment of malignant lung tumors. Follow-up CT examinations of 14 patients (seven men, seven women; age range, 30-90 years) who underwent 16 RFA sessions for the treatment of primary (n = 9) or metastatic (n = 5) lung tumors with a mean follow-up of 35 +/- 15 (SD) months (range, 7-60 months) were retrospectively reviewed by two thoracic radiologists. The site and size of hilar and mediastinal lymph nodes were recorded at baseline and at follow-up 1, 3, and 6 months after RFA sessions. In addition, the size, type, and location of the ablated lesion or lesions were recorded. All complications from RFA were recorded. Data were analyzed using the Fisher's exact test. An increase in lymph node size was detected after 10 of 16 (62.5%) RFA sessions at 1-month follow-up. In four of 10 patients, only one node had enlarged, and in the remaining six patients, more than one nodal region had enlarged. The average increase in nodal size was 3 mm in the short-axis diameter and 4 mm in the long-axis diameter. Twenty-eight percent of RFA sessions were associated with enlargement of at least one lymph node to greater than 10 mm in short-axis diameter at 1-month follow-up. CT showed that nodes had decreased in size at 3- and 6-month follow-ups. Lesion size, location, and complications were not shown to be significantly associated with mediastinal lymph node enlargement (p > 0.05). Recognition of reversible locoregional lymph node enlargement after RFA is important to prevent misdiagnosis of nodal metastatic disease.

The case report on squamous cell carcinoma in Oscar (Astronotus ocellatus)

The presence of squamous cell carcinoma is reported in an Oscar (Astronotus ocellatus) from Urmia (north western part of Iran), Iran. Clinical observations revealed a small pink nodule (1 × 1 mm) on the right-hand side of the fish's lower mandible with a gradual increase in nodule size. After 2 months, the nodule was as large as 1 × 1 cm in size with a white-to-cream colouration. By this time, two similar nodules had formed on the ventral surface of lower mandible. At similar high risk sites around the mouth, another single nodule on the mandible adjacent to the operculum was found. The disorder caused an irregular mouth shape that consequently resulted in the fish unable to close its mouth. All mentioned sites were carefully dissected and processed for histopathological analyses. Observations demonstrated the presence of multiple cell masses under the skin layers, with either picnotic nucleus or without a nucleus and with keratin in the central part of the cell masses. Using specific staining for keratin showed a red-coloured keratin mass (cancer pearl) as a bluish background in the tissue components. The invaded cell masses into dermis showed pleomorphic nuclei.

Lenalidomide Induced Cytokine Release Syndrome in Chronic Lymphocytic Leukemia (CLL): Clinical and Laboratory Correlates of Immune Activation.

Lenalidomide is active in lymphoid malignancies, but its mechanism of action remains ill defined. One possible mechanism is immune activation due to increased expression of costimulatory molecules on tumor cells. In CLL lenalidomide treatment has been uniquely complicated by tumor flare reactions (TFR: pain and lymph node swelling) resulting in treatment related mortality. To investigate effects of lenalidomide on CLL cells we exposed PBMC from 17 CLL patients enrolled in a phase II clinical trial of single agent lenalidomide and normal donors (n=10) in-vitro to 2μM lenalidomide for 48 hours and measured costimulatory molecules CD80 and CD86 on B-cells and activation marker CD69 on T-cells by flow cytometry. CD80 expression increased on average 2-fold on CLL cells but remained unchanged on normal B-cells (p=0.01 for log2 MFI CLL vs normal). CD69 expression on T-cells followed a similar pattern, albeit with more interindividual variability among CLL samples (p=0.03 for log2 MFI CLL vs. normal). Next we wished to correlate the degree of in-vitro activation with the clinical effects of lenalidomide treatment in the same patient. Our observations in several patients suggested that the dominant feature of lenalidomide treatment is a cytokine release syndrome (CRS). Indeed, on day 8 of treatment we detected increased serum levels of TNFa, IL-1ra, CCL2, CCL3, CCL4 and IL-8. To correlate the CRS with in-vitro measurements, we applied uniform criteria for diagnosis. Patients who experienced at least 2 of the following symptoms (% of patients with the symptom, n=18) were considered to have a CRS: increase in lymph node size and or ALC by >25% (50%), fever >38C (44%), pain (61%), fatigue (72%), chills (33%), hypotension/dehydration (39%), and rise of creatinine (33%). Onset of symptoms was within 8 to 72 hours (average 38 hours) after initiation of therapy (20mg patients 1–10, 10mg patients 11–18). The CRS score, summarizing number and severity of symptoms in each patient, averaged 3.14 (range 0–10) with no difference between the 20mg and10mg cohort. The CRS score correlated (Pearson r-value, p<0.01) with: lenalidomide induced increase in CD80 on CLL cells (r=0.67), and increase of CD69 on T-cells (r=0.74), rise in CRP on day 4 (r=0.63), and inversely with treatment induced changes in T-cell numbers (r=−0.7). No correlation was found between the CRS score and the decrease in leukemic cells (mean decrease 40% day 8, 54% day 21). It has been suggested that during the TFR, T-cell numbers in lymphoid organs increase. We therefore scored 11 matched lymph node biopsies taken from the same patient pre-treatment and on day 8 of the first cycle for T-cell content. Only 2 patients had an increase of >50% in CD3+ cells in the lymph node and the average pre/post ratio of T-cells was 1.14 (p=0.37). In summary, lenalidomide upregulated expression of CD80 on B-cells and of CD69 on T-cells from CLL patients but not on normal B and T-cells. The in-vitro response correlated with the clinical onset and severity of a CRS in-vivo. However, the degree of T-cell activation or of the CRS did not predict the effect on the leukemic cell count. Our data suggest the possibility that immune activation in CLL may be primarily responsible for side effects but not be required for disease control. This interpretation is consistent with the good clinical activity of lenalidomide in several lymphoid malignancies in the absence of notable immune effects and if confirmed, has important implications for future use of lenalidomide and the formulation of combination regimens.

Gefitinib prevents cancer progression in mice expressing the activated rat HER2/neu

We tested the efficacy of gefitinib in the prevention of HER2/neu-mediated breast cancer development in BALB-NeuT transgenic mice. Oral administration of gefitinib to female transgenic mice from 5 to 14 weeks of age reduced tumor multiplicity from 9.6 +/- 0.82 to 0.58 +/- 1.1 (83%). We observed a decrease in the number and size of lobules and lobular nodules in treated mice with a reduction in the overall disease burden per gland. Normal duct development in the mammary glands was not affected by gefitinib. The development of acinic cell carcinoma in the parotid glands of these animals was also reduced coincident with decreased stromal involvement during progression. Gefitinib eliminated phosphorylation of HER2 and HER3 and signaling through MAPK and Akt in lobular hyperplasias and carcinomas. At the same time MAPK activity and cytokine production in splenocytes and lymph nodes was increased in gefitinib-treated animals coincident with an increase in lymph node size. Delaying gefitinib treatment until mammary glands exhibited atypical lobular hyperplasias reduced efficacy. These studies demonstrate the critical role of HER2 signal transduction in the onset and progression of HER2/neu-dependent breast cancer and suggest a role for specific inhibitors to prevent the outgrowth of early hyperplastic disease.

Effects on Bone Mineral Density by Treatment of Benign Nodular Goiter with Mildly Suppressive Doses of L-Thyroxine in a Cohort Women Study

Objectives: Thyroid diseases and their treatment may influence the osseous system. The influence that prolonged suppressive L-thyroxine (LT4) therapy may have on inducing subclinical hyperthyroidism on bone metabolism is still a matter of debate. The aim of the present study was to assess the effects of chronic LT4 treatment at mildly inhibiting serum thyroid-stimulating hormone (TSH) doses on bone mineral density (BMD) and biochemical bone remodeling markers in a cohort of women with benign nodular goiter, and to verify the efficacy of the treatment on nodule size. Subjects and Study Design: A total of 200 euthyroid Caucasian women with nodular goiter (age 52.1 ± 9; 80 pre- and 120 postmenopausal) were enrolled: 96 had been treated with LT4 for at least 3 years and a matched group of 104 had untreated goiter. LT4 therapy was given at a dose sufficient to reduce TSH under the lower limit of the normal range (0.27–4.20 µIU/ml) without suppressing it below the limit of assay sensitivity (0.005 µIU/ml) and maintaining normal serum values of free triiodothyronine (FT3) and free thyroxine (FT4). The adequacy of the dose was evaluated on the basis of serum TSH levels. The osteopenic effect of LT4 treatment was evaluated directly by total body and lumbar spine dual-energy X-ray absorptiometry (DEXA) and indirectly by biochemical parameters (alkaline phosphatase, osteocalcin, calcium, parathyroid hormone) at the baseline and throughout the follow-up. The efficacy of LT4 schedule on thyroid nodule size was assessed on the basis of the ultrasonographic evaluation. Results: Mineralometric data showed no significant difference between BMD values for treated and untreated patients in both pre- and postmenopausal status. In all patients, serum markers of bone turnover were in the normal range, with no differences in the treated and control groups. The TSH concentrations were significantly lower in treated than in untreated patients (p < 0.0001); FT3 and FT4 were in the normal range for all patients. Evaluation of nodule size during follow-up showed a reduction of ≧30% in 32 of 96 treated patients (33.3%) versus none in those untreated, whilst nodule size remained unmodified in 60 treated patients (62.5%) versus 35 (33.6%) in those untreated, and an increase in nodule size and/or development of new nodules was found in 4 treated patients (4.2%) versus 69 of the 104 untreated patients (66.3%). Conclusions: This study suggests that at slightly suppressing TSH doses, LT4 therapy has no adverse effects on BMD in both pre- and postmenopausal women, while having an efficacy on nodule size comparable with that reported using an LT4 schedule able to maintain TSH near or below the assay sensitivity limit.

TNF-blocking therapies: an alternative mode of action?

Despite expanding use of drugs blocking tumour necrosis factor (TNF), their precise mechanisms of action remain unclear. Early assumptions that they act by direct neutralization of the toxic inflammatory effects of TNF might be too simplistic because they explain neither the range of effects observed nor the varying properties of different TNF-blocking agents. Recent studies have demonstrated a key role for mast cell-derived TNF in the increase in lymph node size and the organizational complexity that accompanies a developing immune response. Regulation of this phenomenon might comprise a novel mode of action for TNF-directed therapy: by preventing this lymph node hyperplasia, TNF blockade could modulate immune responses, ameliorating pathology in autoimmune diseases, such as rheumatoid arthritis.

Does oxygen limit nitrogenase activity in soybean exposed to elevated CO2?

ABSTRACTSoybean (Glycine max L. Merr) plants grown under control (360 µmol mol−1) or elevated CO2 concentration (800 µmol mol−1) from 33 to 42 d after sowing were assayed for various components of in vivo nitrogenase activity to test the hypothesis that increasing carbohydrate supply to nodules would increase the potential (i.e. O2 saturated) nitrogenase activity and impose a more severe O2 limitation on both nodule metabolism and total nitrogenase activity. Within 51 h of elevated CO2 treatment, significant increases relative to control plants were seen in total nitrogenase activity expressed per plant. After 6 d of elevated CO2, the total nitrogenase activity per plant was 18% higher than that in control. This was attributed to an initial increase in nodule size, and a subsequent increase in nodule number following plant exposure to elevated CO2. However, after 9 d of elevated CO2, the potential and total nitrogenase activities per gram nodule dry weight were lower, not higher than corresponding values in plants in the control treatment. These results did not support the hypothesis. It was concluded that the metabolic capacity of the control nodules were not limited by carbohydrate supply, at least at the assay temperatures employed here.

The Clinical Significance of an Isofunctioning Thyroid Nodule

The management of an "isofunctioning" thyroid nodule--defined by radioiodine uptake equivalent to normal thyroid tissue--is often a dilemma. Our goal was to determine the percentage of thyroid nodules that were isofunctioning and the frequency with which carcinoma occurred in an isofunctioning nodule. Patients referred for evaluation of a thyroid nodule from 1990 to 2002 were reviewed and those with an iodine-123 thyroid scintiscan were identified. Nodule size, serum thyrotropin, fine-needle aspiration biopsy, pathology, and follow-up were determined for patients with an isofunctioning, hypofunctioning, or hyperfunctioning thyroid nodule. Of the 562 patients with a thyroid nodule 273 (49%) had a thyroid scan. Nodules were hypofunctioning in 232 (85%), isofunctioning in 29 (11%), and hyperfunctioning in 12 (4%) patients. Mean nodule size and serum thyrotropin level were respectively 2.49 +/- 0.23 cm and 1.73 +/- 0.26 microIU/mL for isofunctioning, 2.47 +/- 0.31 cm and 0.83 +/- 0.21 microIU/mL for hyperfunctioning, and 3.94 +/- 0.13 cm and 1.86 +/- 0.28 pIU/mL for hypofunctioning nodules. Seventeen patients with an isofunctioning nodule underwent thyroidectomy and 12 patients were followed for a mean 27 months without an increase in nodule size. No patient with a hyperfunctioning nodule, six patients (21%) with an isofunctioning nodule, and 44 patients (19%) with a hypofunctioning nodule had a carcinoma. We conclude that the risk of malignancy in an isofunctioning nodule is similar to that of a hypofunctioning nodule and therefore the management should be based on routine fine-needle aspiration biopsy.

Factors affecting the nodule size of asymmetric PMMA membranes

Several factors that may affect the surface nodule size of a polymeric membrane were under investigation. The increase of polymer concentration and molecular weight were found to increase the surface nodule size. The increase of casting temperature also resulted in an increase in nodule size. These results supported that the radius of gyration and the collision frequency between polymer chains were the key factors affecting the nodule size. However, when the radius of gyration was reduced by the use of a poor solvent or by pre-adding nonsolvent in the casting solution, the surface nodule size increased. It suggested that there existed other factors affecting the nodule size on membrane surface besides the gyration radius and the collision frequency of polymer chains. In this study, we found in most cases that the surface nodule size decreased along with the surface tension difference between the casting solution and the coagulant. To demonstrate the effect of surface tension, we examined the nodule size inside the membranes where the nodule formation was not significantly affected by the interfacial tension. Opposite to what was observed on the surface, the nodule size increased with the solvation power of the solvent. This result suggested that it was the interfacial tension that overpowered the gyration radius in affecting the surface nodule size.

Evaluation of Auricular Lymph Node Cell Proliferation in Isothiazolone-Treated Mice

Evaluation of Auricular Lymph Node Cell Proliferation in Isothiazolone-Treated Mice. Potter, D. W., and Hazelton, G. A. (1995). Fundam. Appl. Toxicol. 24, 165-172.Chemicals that bind to protein may cause immunological responses that include allergic contact hypersensitivity mediated by T cells. Various animal models have been used to predict chemical-mediated contact sensitization. One assay that has recently been developed utilizes the proliferation response induced in the draining auricular lymph node after exposure to contact sensitizers. This assay has been modified to a simpler method that results in the more rapid processing of samples with greater reproducibility. Isothiazolones are chemicals used as biocides in various applications which at greater than use concentrations may cause allergic contact hypersensitivity. The mouse auricular lymph node cell proliferation assay has been used to examine the potential of various isothiazolones to induce contact sensitization. The extent of lymph node cell proliferation was dependent on the concentration of isothiazolone, the vehicle used in the application, and the ability of isothiazolone to bind to protein. Kathon biocide contains two isothiazolones: 5-chloro-2-methyl-4-isothiazolin-3-one (CMI)2 and 2-methyl-4-isothiazolin-3-one (MI). In vivo studies have shown that protein binding correlates with auricular lymph node cell proliferation and an increase in auricular lymph node size. CMI, which binds to protein, induced an auricular lymph node cell proliferation response while MI, which poorly binds to protein, neither stimulated a proliferative response nor induced an increase in lymph node size at concentrations similar to CMI. In other studies that compared the auricular lymph node cell proliferation of four different isothiazolones, it was shown that dramatically different proliferation responses were observed and that these responses were positively correlated with contact sensitization in the guinea pig.

Evidence for the formation of different‐sized nodules by different accretionary processes

Abstract Studies on different‐sized polymetallic nodules from the Central Indian Ocean Basin reveal that chemical composition is largely related to the nodule diameter which show systematic decrease in Mn, Cu, and Ni content with increase in nodule size. S and I type nodules are more abundant than B, L, and V types. Nodules grouped according to their size have common morphological, mineralogical, and geochemical characteristics and all six groups have distinguishing properties. There is evidence which suggests that the smaller (M and I) nodules are diagenetic and the larger (S, B, L, and V) are hydrogenetic, exhibiting variations in todorokite abundance and in chemical composition. There is also substantial evidence that the nodules of high economic value (Cu + Ni + Co%) can be sorted out on the basis of simple morphological parameters.

Short course chemotherapy for tuberculous lymphadenitis in children.

To assess the efficacy of a short course chemotherapy regimen for treating tuberculosis of the lymph nodes in children. Open, collaborative, outpatient clinical trial. Outpatient department of the Tuberculosis Research Centre, paediatric surgery departments of the Institute of Child Health and Hospital for Children and the Government Stanley Hospital, Madras, South India. Children aged 1-12 years with extensive, multiple site, superficial tuberculous lymphadenitis confirmed by biopsy (histopathology or culture). Patients were treated with a fully supervised intermittent chemotherapy regimen consisting of streptomycin, rifampicin, isoniazid, and pyrazinamide three times a week for two months followed by streptomycin and isoniazid twice a week for four months on an outpatient basis. Surgery was limited to biopsy of nodes for diagnosis and assessment. Response to chemotherapy was assessed by regression of lymph nodes and healing of sinuses and abscesses during treatment and follow up. Compliance with treatment and frequency of adverse reactions were also estimated. 197 Patients were admitted to the study and 168 into the analysis. The regimen was well tolerated and compliance was good with 101 (60%) patients receiving the prescribed chemotherapy within 15 days of the stipulated period of six months. Those whose chemotherapy extended beyond that period received the same total number of doses. Clinical response was favourable in most patients at the end of treatment. Sinuses and abscesses healed rapidly. Residual lymphadenopathy (exceeding 10 mm diameter) was present in 50 (30%) patients at the end of treatment; these nodes were biopsied. Fresh nodes, increase in size of nodes, and sinuses and abscesses occurred both during treatment and follow up. After 36 months of follow up after treatment only 5 (3%) patients required retreatment for tuberculosis. Tuberculous lymphadenitis in children can be successfully treated with a short course chemotherapy regimen of six months.