On combining the beam path of similar wavelength lasers for dual-laser Thomson scattering

A novel method for the path combination of two lasers with very similar wavelengths has been implemented to enable the evaluation of a dual-laser calibration Thomson scattering (TS) technique. The first experimental test of this TS technique has been performed in a RFX-mod plasma device, where, due to experimental constraints, the combination of a Nd:YAG (λ = 1064 nm) and a Nd:YLF (λ = 1053 nm) laser system was the only viable choice available. The method requires that the beam path of both lasers be combined into a single path with the same polarization. This presents a unique challenge due to the small difference between the two laser wavelengths. In this paper, we describe two methods for beam combination: first via a prism, eventually dismissed as unpractical, and second via a polarizing beam splitter in reverse with a dual-wavelength waveplate. We detail the optical setup, waveplate design, and successful implementation of this second method.

Design of JT-60SA core Thomson scattering diagnostic system

An incoherent Thomson scattering diagnostic will be installed in the JT-60SA tokamak to measure electron temperature and electron density profiles. The target radial spatial resolution is 25 mm with 46 spatial channels. The accuracy in electron temperature and density is a few percent at n_e = 7.5 × 10¹⁹ m^-3, which is the expected value in the plasma core. This paper presents the designs of collection optics, fibers with their alignment system, and polychromators. The collection optics overcomes unique issues for superconducting fusion devices, i.e., limited design space, high-temperature measurements, and harsh radiation condition. When in several years the more performing plasma will generate intense nuclear radiation, the lens materials of the optics can be replaced by radiation resistant glasses without major changes in the lens holder. It will prevent transmission degradation and keep stable measurement accuracy.

CRISP: A compact RF ion source prototype for emittance scanner testing

A movable Allison type emittance scanner is being developed to characterize the phase-space distribution of the beamlets of spectral phase interferometry for direct electric-field reconstruction, the prototype RF negative ion source of the ITER heating neutral beam injector. To test the electronics and verify the capability of the device to resolve nearby beamlets, a compact RF ion source prototype has been set up, capable of accelerating 1 mA of helium ions up to a voltage of 2 kV. A commercial 100 W RF generator creates a plasma inside a Pyrex tube, with a density between 10¹⁵ and 10¹⁶ m^-3 and an electron temperature up to 15 eV. Three multi-aperture grids in accel-decel configuration extract and accelerate the ions, which are measured with a Faraday cup. We present in this paper the characterization of the ion source and its first operation, showing that it is suitable for the commissioning of the Allison scanner.

Low Expression of miR-424-3p is Highly Correlated with Clinical Failure in Prostate Cancer

Prostate cancer (PC) is a highly heterogenous disease and one of the leading causes of mortality in developed countries. Recently, studies have shown that expression of immune checkpoint proteins are directly or indirectly repressed by microRNAs (miRs) in many types of cancers. The great advantages of using miRs based therapy is the capacity of these short transcripts to target multiple molecules for the same- or different pathways with synergistic immune inhibition effects. miR-424 has previously been described as a biomarker of poor prognosis in different types of cancers. miR-424 is also found to target both the CTLA-4/CD80- and PD-1/PD-L1 axis. In the present study, the clinical significance of miR-424-3p expression in PC tissue was evaluated. Naïve radical prostatectomy specimens from 535 patients was used for tissue microarray construction. In situ hybridization was used to evaluate the expression of miR-424-3p and immunohistochemistry was used for CTLA-4 protein detection. In univariate- and multivariate analyses, low expression of miR-424-3p was significant associated with clinical failure-free survival, (p = 0.004) and p = 0.018 (HR:0.44, CI95% 0.22-0.87). Low expression of miR-424-3p also associated strongly with aggressive phenotype of PC. This highlight the importance of miR-424-3p as potential target for therapeutic treatment in prostate cancer.

The Extent of Surgery for Thyroid Medullary Cancer

Aims

Evaluation of the impact of the extent of primary surgery and reintervention on the outcome of patients with medullary thyroid carcinoma.

Methods

Seventy-two patients with medullary thyroid carcinoma (MTC) were surgically treated between 1967 and 1992.

Results

Fifty-five cases were sporadic, 5 patients had MEN 2A, 4 MEN 2B syndrome and 8 familial non-MEN MTC; 1 patient had stage I disease, 30 patients stage II, 36 stage III and 5 stage IV. Sixty-four had their initial treatment at our center, and 8 came for subsequent treatment. At first treatment, 8 patients were subjected to partial thyroidectomy, 10 to total thyroidectomy, 53 to total thyroidectomy with neck dissection, and 1 to only radical neck dissection; postoperative serum calcitonin (Ct) levels returned to normal in 3, 6 and 27 patients, respectively. In the patient with only radical neck dissection, Ct levels remained elevated. No patient with Ct normalization after surgery became responsive to pentagastrin in the follow-up. Thirteen patients had a reoperation due to nodal relapse. At a mean follow-up of 5.7 years (6-252 months), the 10-year survival rate was 84.5% with a significant difference between patients under and over 40 years of age (96.4 vs 57%), between stage I-II (100%) and stage III, IV (83.8%, 0% respectively). At the last follow-up, 36 (50%) patients were alive and disease free and 26 were alive with disease (15 with distant metastases). Of the 10 deaths, 7 were due to tumor recurrence, 3 to 120 months after surgery.

Conclusions

Data suggest that an earlier diagnosis rather than more extensive surgery could improve survival and reduce recurrences. However, the least treatment required is total thyroidectomy plus central neck and upper mediastinum clearance and in addition, according to the extent of nodal involvement, mono- or bilateral neck dissection. To avoid ineffective reoperation due to distant (mainly liver) micro-metastases, persistent residual microscopic disease requires a more aggressive restaging.

Frequency of Thyroid Carcinoma in a Recent Series of 539 Consecutive Thyroidectomies for Multinodular Goiter

Aims and background

The aim of the study was to analyze the frequency of thyroid carcinoma in a consecutive series of 539 thyroidectomies for multinodular goiter (MNG) and to assess the influence of sex and age as cancer risk factors.

Methods

In a 2-year period, 539 patients underwent subtotal or total thyroidectomy for MNG at the Institute of General Surgery, University of Padova, Padova, Italy: 455 were females and 84 males (F/M = 5.5/1); mean age was 46 years (min. 17, max 78). Only 17 patients (3.1%) (16 females and 1 male) were aged 21 years or less.

Results

A malignancy was found in 41 patients: 38 females and 3 males; 39 older and 2 younger than 21 years. The frequency of cancer in MNG was 7.6%: 8.3% in females and 3.6% in males; 7.5% in patients older than 21 and 11.7% under 21 years.

Conclusions

The combination of MNG and carcinoma should always be carefully considered but not overemphasized, and the policy of surgically treating all patients with MNG is not justified. Sex and age cannot be considered as factors of a higher risk of cancer.

High Prevalence of Occult Papillary Thyroid Carcinoma in a Surgical Series for Benign Thyroid Disease

In a surgical series of 277 consecutive patients operated on the thyroid for benign diseases, a high prevalence rate (10.5%) of occult papillary carcinoma was found by means of an accurate histologic examination. Indications for surgery were euthyroid multinodular goiter in 25 patients, autonomously hyperfunctioning adenoma in 2 and Graves’ disease in 2 patients. Neoplastic foci were unilaterally found in 25 cases but multifocally in 6 and bilaterally in 4 cases: the diameters ranged from 2-10 mm. After operation (14 subtotal and 15 total thyroidectomies), all patients received TSH-suppressive doses of T4. At a mean follow-up of 5.6 years, neither local recurrences nor lymph node or distant metastases had occurred; no patient died of the tumor. In keeping with other surgical and autopsy series, the prevalence of occult thyroid carcinoma in a normal population is calculated to be about 5-10%, whereas it is known that the prevalence of clinically evident thyroid cancer is only 0.05%. This means that only 1-2% of occult carcinomas may evolve in an overt tumor during life. In view of such an epidemiologic difference and the favorable course of our patients, although the mean follow-up is rather short, we suggest that lobectomy plus T4 treatment may be considered an adequate therapeutic approach in patients with occult papillary thyroid carcinoma.

Diet and Epithelial Cancer of the Thyroid Gland

Enhanced secretion of thyroid stimulating hormone (TSH) has been linked with increased risk of thyroid carcinoma. Diet can increase TSH secretion in various ways: 1) low iodine intake, 2) high goitrogen intake, especially in subjects living in iodine-deficiency areas and 3) direct stimulation of anterior pituitary gland. Excessive iodine intake, however, has also been shown to increase risk of goitre and, perhaps, also thyroid carcinoma. Epidemiological evidence on the role of diet in the etiology of thyroid carcinoma is reviewed here. Ad hoc studies in affluent countries are few and often conflicting. A case-control study conducted in the North of Italy suggests that perhaps dietary aspects other than iodine or goitrogens (i.e. fresh fruit and vegetables and animal fat) may be involved.

Image-guided fine-needle aspiration cytology and flow cytometry phenotyping of neck lymphadenopathy for the diagnosis of recurrent lymphoma

OBJECTIVE

In patients with a history of lymphoma, each lymphadenopathy should be carefully evaluated. The aims of this study were to evaluate (i) the usefulness of high-resolution ultrasonography (US), US-guided fine-needle aspiration cytology (FNAC) and flow cytometry phenotyping (FCP) together in the diagnosis of recurrent lymphoma and (ii) whether these tools were independent predictors of correct results.

DESIGN

Retrospective cohort study with stepwise forward logistic regression analysis of results.

SETTING

Tertiary referral centre.

PARTICIPANTS

A total of 151 patients with a history of lymphoma who developed a cervical mass during follow-up.

METHODS

On neck US, a lymphadenopathy was shown in 129 (85.4%) patients (median age 57 years, range 18-78 years), and US-guided FNAC combined with FCP were immediately performed. All patients had surgical excision and subsequent histological examination of the enlarged node(s), to establish lymphoma subclassification.

RESULTS

Final histology confirmed recurrence in 82 (63.6%) patients. According to the logistic regression analysis, FNAC and FCP were independent predictors of correct results (P = 0.009 and 0.028, respectively) and did not interfere with each other. The sensitivity, specificity and accuracy of the combination of all of the tools were 98.8%, 100% and 99.2%, respectively, and the area under the receiver operating characteristic curve was 0.902 (95% CI: 0.797-0.986).

CONCLUSION

This minimally invasive procedure is easily performed and should be recommended for all patients with cervical lymphadenopathy and a history of lymphoma, avoiding the need of core-biopsy or surgical excision if recurrence was excluded.

Internal Transport Barrier Broadening through Subdominant Mode Stabilization in Reversed Field Pinch Plasmas

The reversed field pinch (RFP) device RFX-mod features strong internal transport barriers when the plasma accesses states with a single dominant helicity. Such transport barriers enclose a hot helical region with high confinement whose amplitude may vary from a tiny one to an amplitude encompassing an appreciable fraction of the available volume. The transition from narrow to wide thermal structures has been ascribed so far to the transport reduction that occurs when the dominant mode separatrix, which is a preferred location for the onset of stochastic field lines, disappears. In this Letter we show instead that the contribution from the separatrix disappearance, by itself, is marginal and the main role is instead played by the progressive stabilization of secondary modes. The position and the width of the stochastic boundary encompassing the thermal structures have been estimated by applying the concept of a 3D quasiseparatrix layer, developed in solar physics to treat reconnection phenomena without true separatrices and novel to toroidal laboratory plasmas. Considering the favorable scaling of secondary modes with the Lundquist number, these results open promising scenarios for RFP plasmas at temperatures higher than the presently achieved ones, where lower secondary modes and, consequently, larger thermal structures are expected. Furthermore, this first application of the quasiseparatrix layer to a toroidal plasma indicates that such a concept is ubiquitous in magnetic reconnection, independent of the system geometry under investigation.

Guidelines for the Cytopathologic Diagnosis of Epithelioid and Mixed-Type Malignant Mesothelioma: a secondary publication

OBJECTIVE

To provide practical guidelines for the cytopathologic diagnosis of malignant mesothelioma.

DATA SOURCES

Cytopathologists with an interest in the field involved in the International Mesothelioma Interest Group (IMIG) and the International Academy of Cytology (IAC) contributed to this update. Reference material includes peer-reviewed publications and textbooks.

RATIONALE

This article is the result of discussions during and after the IMIG 2012 conference in Boston, followed by thorough discussions during the 2013 IAC meeting in Paris. Additional contributions have been obtained from cytopathologists and scientists who could not attend these meetings, with final discussions and input during the IMIG 2014 conference in Cape Town.

A feasibility study of a NBI photoneutralizer based on nonlinear gating laser recirculation

The neutralization efficiency of negative ion neutral beam injectors is a major issue for future fusion reactors. Photon neutralization might be a valid alternative to present gas neutralizers, but still with several challenges for a valid implementation. Some concepts have been presented so far but none has been validated yet. A novel photoneutralization concept is discussed here, based on an annular cavity and a duplicated frequency laser beam (recirculation injection by nonlinear gating). The choice of lithium triborate as the material for the second harmonic extractor is discussed and a possible cooling method via crystal slicing is presented; laser intensity enhancement within the cavity is evaluated in order to quantify the achievable neutralization rate. Mockups of the critical components are proposed as intermediate steps toward system realization.

An analysis of different therapeutic options in patients with Cushing's syndrome due to bilateral macronodular adrenal hyperplasia: a single-centre experience

CONTEXT

Bilateral macronodular adrenal hyperplasia (BMAH) is a rare form of Cushing's syndrome (CS). A variety of in vivo tests to identify aberrant receptor expression have been proposed to guide medical treatment. Unilateral adrenalectomy (UA) may be effective in selected patients, but little is known about recurrence during follow-up.

OBJECTIVE

To describe a series of patients with BMAH and CS treated by different approaches, with a particular focus on the benefit of UA.

DESIGN AND PATIENTS

We retrospectively assessed 16 patients with BMAH and CS (11 females, five males), analysing the in vivo cortisol response to different provocative tests. Twelve of the 16 patients underwent UA and were monitored over the long term.

RESULTS

Based on in vivo test results, octreotide LAR or propranolol was administered in one case of food-dependent CS and two patients with a positive postural test. A significant improvement in biochemical values was seen in all patients but with limited clinical response. UA was performed in 12 patients, producing long-term remission in three (106 ± 28 months; range: 80-135), recurrence in eight (after 54 ± 56 months; range 12-180) and persistence in one other. Four patients subsequently underwent contralateral adrenalectomy for overt CS, one received ketoconazole, and four other patients remain under observation for subclinical CS.

CONCLUSIONS

Medical treatment based on cortisol response to provocative tests had a limited role in our patients, whereas UA was useful in some of them. Although recurrence is likely, the timing of onset is variable and close follow-up is mandatory to identify it.

Edge Thomson scattering diagnostic on COMPASS tokamak: installation, calibration, operation, improvements

The core Thomson scattering diagnostic (TS) on the COMPASS tokamak was put in operation and reported earlier. Implementation of edge TS, with spatial resolution along the laser beam up to ∼1/100 of the tokamak minor radius, is presented now. The procedure for spatial calibration and alignment of both core and edge systems is described. Several further upgrades of the TS system, like a triggering unit and piezo motor driven vacuum window shutter, are introduced as well. The edge TS system, together with the core TS, is now in routine operation and provides electron temperature and density profiles.

Dual-angle, self-calibrating Thomson scattering measurements in RFX-MOD

In the multipoint Thomson scattering (TS) system of the RFX-MOD experiment the signals from a few spatial positions can be observed simultaneously under two different scattering angles. In addition the detection system uses optical multiplexing by signal delays in fiber optic cables of different length so that the two sets of TS signals can be observed by the same polychromator. Owing to the dependence of the TS spectrum on the scattering angle, it was then possible to implement self-calibrating TS measurements in which the electron temperature Te, the electron density ne and the relative calibration coefficients of spectral channels sensitivity Ci were simultaneously determined by a suitable analysis of the two sets of TS data collected at the two angles. The analysis has shown that, in spite of the small difference in the spectra obtained at the two angles, reliable values of the relative calibration coefficients can be determined by the analysis of good S/N dual‑angle spectra recorded in a few tens of plasma shots. This analysis suggests that in RFX-MOD the calibration of the entire set of TS polychromators by means of the similar, dual-laser (Nd:YAG/Nd:YLF) TS technique, should be feasible.

Experimental observation of microtearing modes in a toroidal fusion plasma

Experimental evidences of short wavelength electromagnetic modes are found in the reversed-field-pinch configuration device RFX-mod by means of in-vessel magnetic probes. The modes are revealed during the helical states of the plasma. Their amplitude is well correlated to the electron temperature gradient strength in the core. On the basis of linear gyrokinetic calculations we interpret these instabilities as microtearing modes.

The glucose-dependent insulinotropic polypeptide receptor is overexpressed amongst GNAS1 mutation-negative somatotropinomas and drives growth hormone (GH)-promoter activity in GH3 cells

Somatic mutations in the GNAS1 gene, encoding the α-subunit of the heterotrimeric stimulatory G protein (Gαs), occur in approximately 40% of growth hormone (GH)-secreting pituitary tumours. By altering the adenylate cyclase-cAMP-protein kinase A pathway, they unequivocally give somatotroph cells a growth advantage. Hence, the pathogenesis of somatotropinomas could be linked to anomalies in receptors coupled to the cAMP second-messenger cascade. Among them, the glucose-dependent insulinotropic polypeptide receptor (GIPR) is already known to play a primary role in the impaired cAMP-dependent cortisol secretion in patients affected by food-dependent Cushing's syndrome. In the present study, 43 somatotropinomas and 12 normal pituitary glands were investigated for GIPR expression by quantitative reverse transcriptase-polymerase chain reaction, western blotting and immunohistochemistry. Tumoural specimens were also evaluated for GNAS1 mutational status. The effect of GIPR overexpression on cAMP levels and GH transcription was evaluated in an in vitro model of somatotropinomas, the GH-secreting pituitary cell line GH3. GIPR was expressed at higher levels compared to normal pituitaries in 13 GNAS1 mutation-negative somatotropinomas. GIP stimulated adenylyl cyclase and GH-promoter activity in GIPR-transfected GH3 cells, confirming a correct coupling of GIPR to Gαs. In a proportion of acromegalic patients, GIPR overexpression appeared to be associated with a paradoxical increase in GH after an oral glucose tolerance test. Whether GIPR overexpression in acromegalic patients may be associated with this paradoxical response or more generally involved in the pathogenesis of acromegaly, as suggested by the mutually exclusive high GIPR levels and GNAS1 mutations, remains an open question.

Somatostatin receptor expression in adrenocortical tumors and effect of a new somatostatin analog SOM230 on hormone secretion in vitro and in ex vivo adrenal cells

BACKGROUND

Somatostatin is a widely distributed polypeptide that modulates endocrine and exocrine secretion, cell proliferation, and apoptosis by 5 somatostatin receptors (SSTR1-5). The inhibitory effects of somatostatin on tumor growth may be the result of its suppressing the synthesis and/or secretion of growth factors and growth-promoting hormones.

AIM

Very little information is available on the effect of somatostatin analogs on adrenal tumors, so we examined SSTR expression in adrenocortical tumors and studied the effect of a somatostatin analog (SOM230) on hormone secretion and cell viability in adrenal cells.

MATERIAL/SUBJECTS AND METHODS

SSTR expression was analyzed by real-time PCR in 13 adrenocortical carcinomas (ACC), 24 aldosterone-producing adenomas (APA), 11 cortisol-producing adenomas (CPA), and 7 normal adrenals (NA), and verified by immunohistochemistry (IHC) in 14 samples. The effect of SOM230 on cortisol or aldosterone secretion in H295R and primary cell cultures was determined by radioimmunoassay, and its effect on viability in H295R and SW13 using the MTT test.

RESULTS

SSTR1 and SSTR2 mRNA was expressed in 100% of adrenal tumors. Compared to NA, ACC revealed an increase in almost all SSTR, while only some APA over-expressed SSTR3 and SSTR1. CPA expressed SSTR similar to NA. IHC confirmed the mRNA expression data. At nanomolar concentrations, SOM230 inhibited hormone secretion in primary adrenal cultures and H295R cells, but had no evident effect on cell viability.

CONCLUSIONS

The evidence of SSTR over-expression (particularly in ACC) and of hormone secretion being inhibited by SOM230 suggests a potential therapeutic role for this broad-spectrum somatostatin analog in adrenal tumors.

A case of primary aldosteronism in pregnancy: do LH and GNRH receptors have a potential role in regulating aldosterone secretion?

OBJECTIVE

The mechanisms inducing steroidogenesis in primary aldosteronism (PA) remain poorly defined. It was recently demonstrated that some G-protein-coupled receptors are abnormally expressed in aldosterone-producing adenomas (APA). We evaluated the potential role of LH and GNRH receptors (LHR (or LHCGR) and GNRHR) in regulating aldosterone secretion in a patient with APA arising during pregnancy (index case) and in a subset of other patients with PA.

PATIENTS AND METHODS

GNRH test was performed in the index case, 11 other PA, and 5 controls. GNRHR and LHR expressions were examined in 23 APA and 6 normal tissues.

RESULTS

Aldosterone response increased significantly (114%) in the index case after GNRH test was performed preoperatively, while it was blunted after adrenalectomy. Aldosterone also increased after human chorionic gonadotropin and triptorelin stimulation. A partial aldosterone response to GNRH was observed in other 7/11 PA, while a significant response was observed in two patients. Controls did not respond to GNRH test. GNRHR was overexpressed and LHR expression was moderate in the APA tissue from the index case. Moreover, LHR was found in normal adrenals and overexpressed in 6/22 APA. GNRHR was overexpressed in 6/22 APA, 2 of them with a 95- and 109-fold higher expression than normal. A correlation between the clinical and molecular findings was observed in five out of seven patients.

CONCLUSION

We describe a case of PA diagnosed during pregnancy, which appeared to correlate with aberrant LHR and GNRHR expression. Our findings suggest that a subset of patients with PA has aberrant LHR and GNRHR expression, which could modulate aldosterone secretion.

Diagnostic terminology for reporting thyroid fine needle aspiration cytology: European Federation of Cytology Societies thyroid working party symposium, Lisbon 2009

A European Federation of Cytology Societies (EFCS) working party of 28 members from 14 European countries met at the European Congress of Cytology in Lisbon in September 2009, with two observers from the USA, to discuss the need for standardising thyroid FNA nomenclature in the light of the National Institute of Cancer (NCI) recommendations resulting from the State of the Science conference in Bethesda in 2007. The data were obtained through two questionnaires sent by email and a transcript of the live discussion at the congress, which is presented in full. The surveys and discussion showed that there were currently no national terminologies for reporting thyroid FNA in the different European countries except in Italy and the UK. Personal, 'local', surgical pathology and descriptive terminologies were in use. All but one of the working party members agreed that thyroid FNA reporting should be standardised. Whilst almost a third would adopt the NCI Bethesda terminology, which offers the advantages of a 'risk of cancer' correlation and is linked to clinical recommendations, more than half favoured a translation of local terminology as the first step towards a unified nomenclature, as has been done recently in the UK. There was some disagreement about the use of: a) the six-tiered as opposed to four or five-tiered systems, b) the use of an indeterminate category and c) the 'follicular neoplasm' category, which was felt by some participants not to be different from the 'suspicious of malignancy' category. The conclusions will be passed to the different national societies of cytology for discussion, who will be asked to map their local terminologies to the Bethesda classification, observe its acceptance by clinicians and audit its correlation with outcome.

Vanishing magnetic shear and electron transport barriers in the RFX-mod reversed field pinch

We define the safety factor q for the helical plasmas of the experiment RFX-mod by accounting for the actual three-dimensional nature of the magnetic flux surfaces. Such a profile is not monotonic but goes through a maximum located in the vicinity of the electron transport barriers measured by a high resolution Thomson scattering diagnostic. Helical states with a single axis obtained in viscoresistive magnetohydrodynamic numerical simulations exhibit similar nonmonotonic q profiles provided that the final states are preceded by a magnetic island phase, like in the experiment.

Impurities removal by laser blow-off from in-vacuum optical surfaces on RFX-mod experiment

An in situ window cleaning system by laser blow-off through optical fiber has been developed on the basis of a feasibility study previously presented. The beam generated by a Q-switched Nd:YAG laser is launched in a vacuum box into a high damage threshold optical fiber through a lens. The fiber output is focused on the impurities-coated surface of a vacuum window exposed to the plasma of the RFX-mod experiment, and it is remotely controlled with an xy motion system to scan the entire surface. We first investigate the energy density threshold necessary to ablate the deposited impurity substrate on removed dirty windows: above threshold, a single laser pulse recovers ∼95% of the window transmission before its exposure to the plasma, while below it the efficiency of the cleaning process is too poor. The system so conceived was then used to clean the three collection windows of the Main Thomson scattering diagnostic on RFX-mod. We also present results obtained applying the same technique to the SiO-protected Al mirror used for the Z(eff) diagnostic: an energy threshold for efficient impurity removal without mirror damage is first identified, then ablation tests are executed and analyzed in terms of recovered reflectivity. The SIMS technique is used both with windows and mirror to study the composition of surfaces before and after the ablation.

Optical measurements for turbulence characterization in RFX-mod edge

The edge of the reversed field pinch experiment RFX-mod (R=2 m, a=0.46 m) is characterized by a complex magnetic topology and strong pressure gradients. A set of fast spectroscopic diagnostics has been designed to characterize both main plasma edge parameters and turbulence, including coherent structures (blobs) and radial profiles of the thermodynamic variables. Measurements of the edge radial profiles of electron density (n(e)), temperature (T(e)), and pressure (P(e)) are obtained by a thermal helium beam diagnostic, which locally measures the ratios of the spectral lines emitted by a neutral He cloud puffed into hydrogen plasma discharges. A gas puff imaging system allows the high frequency (1 MHz bandwidth) measurement of the fluctuations of He I emissivity in the same positions. The system measures both the intermittent behavior of the edge turbulence and n(e), T(e), and P(e) profiles of the corresponding coherent structures, with a resolution down to 6 μs. The optical diagnostics are complemented by a set of triaxial magnetic coils to simultaneously characterize the edge magnetic field.

Detection of EGFR and KRAS mutations on trans-thoracic needle aspiration of lung nodules by high resolution melting analysis

BACKGROUND

EGFR and KRAS are the target genes for tumour response to epidermal growth factor receptor (EGFR) inhibitors.

AIMS

To investigate EGFR and KRAS mutational status with high resolution melting (HRM) analysis applied to cytological material obtained from trans-thoracic needle aspiration (TTNA) in order to better select patients for targeted therapy.

METHODS

DNA was extracted from fixed material of 108 TTNAs under CT guidance, from 108 consecutive patients. In 77 TTNAs (71.3.%) that were positive for non-small cell lung cancer, the variant in exon 21 (the missense mutation at codon 858, L858R) and the deletion in exon 19 (in frame deletion at codons 747-749) of the EGFR gene, and the point mutation in exon 2 of KRAS were investigated with HRM assay using sequencing as the reference "gold standard".

RESULTS

Nine (11.7%) samples were positive for KRAS exon 2 mutations, and two (2.6%) samples were positive for the EGFR exon 21 missense mutation by HRM assay. No deletion at exon 19 for EGFR was detected by HRM analysis. All HRM results were confirmed by direct DNA sequencing.

CONCLUSIONS

HRM analysis of cytological material was accurate for the detection of two major EGFR mutations and KRAS mutations in exon 2. HRM analysis was fast, easy to apply, cheap, highly reproducible, and could be used with small amounts of material, such as is obtainable with needle lavage. Therefore, it may be useful as an adjunct to the cytological report that yields valuable molecular information.

Morphological quality and nucleic acid preservation in cytopathology

BACKGROUND

Fixation is a chemical or physical procedure to prevent the degradation of proteins and tissue morphology. To optimise molecular analysis of archival tissues, it is essential that fixation preserves morphology along with protein epitopes and DNA/RNA integrity.

METHODS

A new formalin-free alcoholic-based fixative, FineFIX, was used to fix 15 serous effusions and 38 fine-needle aspirates, and cellular morphology and nucleic acid quality were evaluated.

RESULTS

The cytomorphology of the effusions and fine-needle aspirates obtained with FineFIX fixation was similar to that obtained with formalin-fixed counterparts. Immunocytochemistry showed comparable results with the traditional fixative, but FineFIX preserved higher-molecular-mass DNA and RNA, as demonstrated by successful PCR of large amplification products of >2000 bp.

CONCLUSIONS

The formalin-free fixative produced not only satisfactory results for immunocytochemistry on cytological smears and cell blocks, but also excellent preservation of DNA and RNA, which can also be efficiently used for sophisticated molecular techniques.

Food-dependent Cushing's syndrome: from molecular characterization to therapeutical results

OBJECTIVE

Cortisol secretion in ACTH-independent macronodular adrenal hyperplasia (AIMAH) may be regulated by the aberrant expression of several G-protein-coupled receptors. Bilateral adrenalectomy is the treatment of choice in most cases. We searched for aberrant receptor expression in a patient with AIMAH and evaluated the response to medical and surgical treatment.

PATIENT

A 35-year-old woman with amenorrhea, hirsutism, and hypertension presented ACTH-independent cortisol secretion with high androgen levels. Abdominal computed tomography showed bilateral adrenal macronodules (4.5 cm right and 1.0 cm left). Scintigraphy with I(131)-norcholesterol showed bilateral uptake, prevalent on the right side. Several in vivo stimulation tests were assessed before and after treatment and in vitro studies were performed after unilateral adrenalectomy.

RESULTS

Plasma cortisol increased after a standard meal test (60%) and oral glucose loading (147%), and the response was blunted by pretreatment with 100 microg s.c. octreotide. The therapy with long-acting release octreotide (octreotide-LAR) showed an improvement in urinary free cortisol (UFC) levels. Unilateral adrenalectomy was performed and histopathology revealed macronodular AIMAH. Cortisol and androgens increased after perifusion of tumoral tissue with glucose-dependent insulinotropic polypeptide (GIP), and GIP and LH-receptor overexpression was found in both the adrenal nodules and the adjacent cortex. After surgery, UFC and androgen levels normalized followed by clinical improvement.

CONCLUSIONS

GIP and LH-receptor expression may coexist in AIMAH, influencing the functional and morphological phenotype. Aberrant hormone receptor expression enables specific pharmacological treatment, but long-term studies are needed to evaluate its real efficacy. Unilateral adrenalectomy may be a safe initial option, particularly for asymmetric bilateral adrenal enlargements.

Risedronate prevents the loss of microarchitecture in glucocorticoid-induced osteoporosis in rats

Osteoporosis is a severe complication of glucocorticoid treatment. Bisphosphonates are a powerful therapeutic option to prevent osteoporotic fractures. The aims of this study were: a) to determine bone alterations induced by therapy with glucocorticoids (GC); b) to establish the efficacy of risedronate (Ris) in the prevention of these effects. We studied 40 female Sprague-Dawley rats randomly divided into 4 groups of treatment, administered 3 times a week sc: 1.

CONTROL

vehicle of methylprednisolone (GC) + vehicle of Ris; 2. Ris: Ris 5 mug/kg body weight vehicle of GC; 3. GC: GC 7 mg/kg + vehicle of Ris; 4. GC+Ris: GC 7 mg/kg, Ris 5 microg/kg. Animals were treated for 30 days and then were sacrificed. Densitometry was performed at baseline and at the end of the treatment. Right tibiae were removed for histomorphometric analyses. The GC group showed a 7% decrease in bone density vs controls (p<0.05), while the GC+Ris group was associated with a 3.5% increase in bone density vs controls (p<0.05). In the GC group, histomorphometric evaluations showed reduced bone volume (BV/TV) and thinning of trabeculae (Tb.Th) vs controls (BV/TV: 31+/-1 vs 35+/-1%, p<0.05; Tb.Th: 43+/-2 vs 50+/-3 microm, p<0.01; Ac.f: 1.8+/-0.2 vs 1.6+/-0.3 N/yr). The GC+Ris group had increased BV/TV and Tb.Th, and reduced Ac.f vs the GC group. Ris also maintained trabecular microarchitecture. At the histological level, glucocorticoid-induced osteoporosis was characterized by decreased bone volume, reduced osteoblastic activity, and deterioration of microarchitecture. Ris counteracted these effects both by prolonging osteoblast activity, and by maintaining bone microarchitecture.

Peroxisome proliferator-activated receptor gamma in the human pituitary gland: expression and splicing pattern in adenomas versus normal pituitary

Pituitary adenomas are slow-growing tumours arising within the pituitary gland. If secreting, they give rise to well-known syndromes such as Cushing's disease or acromegaly; when hormonally inactive, they come to clinical attention often with local mass effects or pituitary deficiency. Peroxisome proliferator-activated receptor gamma (PPARgamma), a nuclear hormone receptor with a key role in fat and glucose metabolism, but also involved in several neoplasia, has recently been detected in pituitary adenomas. In the present study, we evaluated the occurrence and splicing profile of PPARgamma in 43 cases of pituitary adenoma of different subtypes and compared it to 12 normal pituitary glands. By real-time polymerase chain reaction, PPARgamma was expressed as much in adrenocorticotrophic hormone (ACTH)-secreting and ACTH-silent adenomas as in controls, with a moderate underexpression in somatotrophinomas and prolactinomas and overexpression in 54% of nonfunctioning pituitary adenomas (NFPA). There was no apparent qualitative change in the splicing profile of pathological pituitary glands, nor was the presence of specific isoforms with dominant negative effects against PPARgamma detected. Western blotting revealed similar expression levels in the different subgroups of pituitary adenomas and normal glands. Immunohistochemistry confirmed PPARgamma expression in approximately one-half of analysed samples. The intra- and intergroup differences observed in pituitary adenomas may represent new elements in the process of understanding the different clinical responses of Cushing's and Nelson patients to PPARgamma-ligand treatment. Moreover, the higher level of PPARgamma expression detected in the NFPA subgroup may suggest its possible role as a molecular target in these pituitary adenomas, paving the way for investigations on the effectiveness of treatment with thiazolidinediones in such patients.

FISH Assay for THE Detection of Bladder Cancer

We evaluated the sensitivity and specificity of fluorescence in situ hybridization (FISH) performed on the urine specimens of patients under follow-up for superficial bladder cancer. Thirty-seven patients were enrolled and underwent cystoscopy, urinary cytology or biopsy and FISH examination. Urinary cytology and FISH were evaluated in exfoliated urothelial cells from bladder washings. A mixture of fluorescent labeled probes to the centromere of chromosomes 3, 7 and 17, and locus 9p21 was used to assess urinary cells for chromosomal abnormalities indicative of malignancy. Nine patients (24.3%) showed an abnormal cystoscopy, but only five patients showed transitional cell carcinoma at histology. Eighteen patients (48.6%) showed an abnormal FISH: one patient (2.7%) had a positive cytology, and three patients (8.1%) showed an atypical cytology. Patients with both positive cystoscopy and histological examination had a positive FISH, while only one patient had a positive cytology. Patients with positive cystoscopy and negative histological examination had a negative FISH. Three patients with negative cystoscopy and suspicious cytology had a positive FISH.

Ten patients (27%) with both negative cystoscopy and cytology had a positive FISH. The sensitivity of the FISH assay was 100%, 50% for the cytology and 62% for the cystoscopy. The specificity of the FISH assay, cytology and cystoscopy were 66%, 100% and 86%, respectively. The sensitivity of the FISH assay in detecting non-invasive urothelial tumors is worth further studies.

CT-scan, MRI and image-guided FNA cytology of incidental adrenal masses

AIM

The aim of this study was to compare the usefulness of computed tomography (CT)-scan, magnetic resonance imaging (MRI), and fine-needle aspiration (FNA) cytology in patients with incidentally discovered adrenal masses.

PATIENTS AND METHODS

Thirty-four consecutive patients (six men and 28 women, median age of 47 years, range 26-80) with non-functioning adrenal masses of 2 cm or more (median 3.5 cm, range 2-9) were studied. All patients underwent CT-scan, MRI, and image-guided FNA cytology using spinal-type narrow-gauge needles prior to further procedures. Nineteen patients underwent adrenalectomy.

RESULTS

Final pathology showed 13 benign adrenal lesions, four adrenocortical carcinomas, and two unsuspected adrenal metastases. Fifteen patients who did not have surgery were considered definitively as having benign adrenal lesions since the mass was unchanged on CT-scans performed during follow-up. The sensitivity, specificity, and positive predictive value were 66.7, 85.7, and 50.0%, for CT-scan, 83.3, 92.9, and 71.4% for MRI, and 83.3, 100, and 100% (p<0.05) for FNA cytology, respectively.

CONCLUSIONS

Image-guided FNA cytology is a safe and sensitive procedure that may reveal unsuspected adrenal malignancies, and should be performed in all patients with incidentally discovered adrenal masses of more than 2 cm in size.

Follicular dendritic cell tumor of the mediastinum

Follicular dendritic cell tumor (FDT) is a rare neoplasm usually occurring in the laterocervical lymph nodes, but presentations elsewhere are also well documented. We report a case of FDT in a 48-year-old man with myasthenia gravis, in whom a slow-growing mediastinal mass that had been surgically excised manifested after 3 years with a local recurrence in the same site. The lesion was aspirated and cytology showed a tumor composed of groups of oval or elongated cells intermingled with several mature small lymphocytes. On histology, the tumor was highly cellular with abundant perivascular lymphocytic infiltration; large cells with pale, eosinophilic cytoplasm and round nuclei, arranged in fascicles often showed a storiform pattern. Occasional binucleated cells were also present. A panel of antibodies showed positivity only for CD21 and CD35, and a weak response to S-100. Electron microscopy showed that the layer cells had convoluted nuclei and elongated interdigitating processes with desmosome-like junctions. The definitive diagnosis of FDT can be concluded only with positive immunostaining for CD21 and CD35. However, in the presence of a mixed population of lymphocytes and larger eosinophilic cells the hypothesis of FDT should always be considered.