Dual protective effect of the association of plant extracts and fluoride against dentine erosion: In the presence and absence of salivary pellicle

OBJECTIVES

To verify the protective effect of plant extracts associated with fluoride against dental erosion of dentine, in the presence and absence of a salivary pellicle.

METHODS

Dentine specimens (n = 270) were randomly distributed into 9 experimental groups (n = 30/group): GT (green tea extract); BE (blueberry extract); GSE (grape seed extract); NaF (sodium fluoride); GT+NaF (green tea extract and NaF); BE+NaF (blueberry extract and NaF); GSE+NaF (grape seed extract and NaF); negative control (deionized water); and a positive control (commercialized mouthrinse containing stannous and fluoride). Each group was further divided into two subgroups (n = 15), according to the presence (P) or absence (NP) of salivary pellicle. The specimens were submitted to 10 cycles: 30 min incubation in human saliva (P) or only in humid chamber (NP), 2 min immersion in experimental solutions, 60 min of incubation in saliva (P) or not (NP), and 1 min erosive challenge. Dentine surface loss (dSL-10 and dSL-total), amount of degraded collagen (dColl) and total calcium release (CaR) were evaluated. Data were analyzed with Kruskal-Wallis, Dunn's and Mann-Whitney U tests (p>0.05).

RESULTS

Overall, the negative control presented the highest values of dSL, dColl and CaR, and the plant extracts showed different degrees of dentine protection. For the subgroup NP, GSE showed the best protection of the extracts, and the presence of fluoride generally further improved the protection for all extracts. For the subgroup P, only BE provided protection, while the presence of fluoride had no impact on dSL and dColl, but lowered CaR. The protection of the positive control was more evident on CaR than on dColl.

CONCLUSION

We can conclude that the plant extracts showed a protective effect against dentine erosion, regardless of the presence of salivary pellicle, and that the fluoride seems to improve their protection.

Vector-apodizing phase plate coronagraph: design, current performance, and future development [Invited]

Over the last decade, the vector-apodizing phase plate (vAPP) coronagraph has been developed from concept to on-sky application in many high-contrast imaging systems on 8 m class telescopes. The vAPP is a geometric-phase patterned coronagraph that is inherently broadband, and its manufacturing is enabled only by direct-write technology for liquid-crystal patterns. The vAPP generates two coronagraphic point spread functions (PSFs) that cancel starlight on opposite sides of the PSF and have opposite circular polarization states. The efficiency, that is, the amount of light in these PSFs, depends on the retardance offset from a half-wave of the liquid-crystal retarder. Using different liquid-crystal recipes to tune the retardance, different vAPPs operate with high efficiencies (${\gt}96\%$) in the visible and thermal infrared (0.55 µm to 5 µm). Since 2015, seven vAPPs have been installed in a total of six different instruments, including Magellan/MagAO, Magellan/MagAO-X, Subaru/SCExAO, and LBT/LMIRcam. Using two integral field spectrographs installed on the latter two instruments, these vAPPs can provide low-resolution spectra (${\rm{R}} \sim 30$) between 1 µm and 5 µm. We review the design process, development, commissioning, on-sky performance, and first scientific results of all commissioned vAPPs. We report on the lessons learned and conclude with perspectives for future developments and applications.

Domain-driven models yield better predictions at lower cost than reservoir computers in Lorenz systems

Recent advances in computing algorithms and hardware have rekindled interest in developing high-accuracy, low-cost surrogate models for simulating physical systems. The idea is to replace expensive numerical integration of complex coupled partial differential equations at fine time scales performed on supercomputers, with machine-learned surrogates that efficiently and accurately forecast future system states using data sampled from the underlying system. One particularly popular technique being explored within the weather and climate modelling community is the echo state network (ESN), an attractive alternative to other well-known deep learning architectures. Using the classical Lorenz 63 system, and the three tier multi-scale Lorenz 96 system (Thornes T, Duben P, Palmer T. 2017 Q. J. R. Meteorol. Soc. 143, 897-908. (doi:10.1002/qj.2974)) as benchmarks, we realize that previously studied state-of-the-art ESNs operate in two distinct regimes, corresponding to low and high spectral radius (LSR/HSR) for the sparse, randomly generated, reservoir recurrence matrix. Using knowledge of the mathematical structure of the Lorenz systems along with systematic ablation and hyperparameter sensitivity analyses, we show that state-of-the-art LSR-ESNs reduce to a polynomial regression model which we call Domain-Driven Regularized Regression (D2R2). Interestingly, D2R2 is a generalization of the well-known SINDy algorithm (Brunton SL, Proctor JL, Kutz JN. 2016 Proc. Natl Acad. Sci. USA 113, 3932-3937. (doi:10.1073/pnas.1517384113)). We also show experimentally that LSR-ESNs (Chattopadhyay A, Hassanzadeh P, Subramanian D. 2019 (http://arxiv.org/abs/1906.08829)) outperform HSR ESNs (Pathak J, Hunt B, Girvan M, Lu Z, Ott E. 2018 Phys. Rev. Lett. 120, 024102. (doi:10.1103/PhysRevLett.120.024102)) while D2R2 dominates both approaches. A significant goal in constructing surrogates is to cope with barriers to scaling in weather prediction and simulation of dynamical systems that are imposed by time and energy consumption in supercomputers. Inexact computing has emerged as a novel approach to helping with scaling. In this paper, we evaluate the performance of three models (LSR-ESN, HSR-ESN and D2R2) by varying the precision or word size of the computation as our inexactness-controlling parameter. For precisions of 64, 32 and 16 bits, we show that, surprisingly, the least expensive D2R2 method yields the most robust results and the greatest savings compared to ESNs. Specifically, D2R2 achieves 68 × in computational savings, with an additional 2 × if precision reductions are also employed, outperforming ESN variants by a large margin. This article is part of the theme issue 'Machine learning for weather and climate modelling'.

Black and south asian women’s pathways to accessing community and inpatient perinatal mental health services: An analysis of local service data from the paam study

Introduction

Women from ethnic minorities who experience mental health problems during the perinatal period are disproportionately represented in involuntary care. They have poorer access to community care but have higher engagement with services once accessed. Their pathways to accessing perinatal mental health care remain underexplored.

Objectives

To investigate the pathways to perinatal mental health services for women across different ethnic groups, including number of caregivers encountered and time elapsed between referrals.

Methods

Analysis of patient records and routine service data from community and inpatient perinatal mental health services in the United Kingdom. Use of an adaptation of the WHO’s pathway encounter form.

Results

Women from ethnic minority groups experience increased levels of complexity on their journey to accessing perinatal mental health care. We will present a detailed analysis of patient and service characteristics.

Conclusions

Referral pathways to perinatal mental health services need to be optimised for women from underrepresented groups.

Effect of circadian rhythm on the pain associated with preventive onabotulinumtoxinA injections for migraines

The aim of our research was to assess if the pain and discomfort following each quarterly onabotulinumtoxinA (BTA) injection given to prevent daily headaches/migraines is circadian time-dependent so as to determine the best administration time for least discomfort and minimal follow-up pain. A total of 61 diurnally active patients with a medical history of chronic migraine headaches and undergoing preventative BTA injection therapy for the first time were enrolled in the study. Patients were randomly assigned to morning or afternoon clinics, but had the ability to choose within the assigned clinic the injection time that best fits their schedule. 155 units of BTA was administered by following the standardized PREEMPT injection protocol. Patients reported the typical time of sleep onset and wakeup time for the week prior to injections. Patients then self-reported three levels of pain in the head and neck area: prior to BTA injections, immediately after, and 24 h after BTA injections. This was carried out by marking the pain level on 100 mm visual analog pain scale. Descriptive summaries were frequencies and percentages for categorical data and medians and quartiles for continuous variables. Demographic variables of gender, race, and age were tested using Chi-Square. Groups of morning versus afternoon patients were compared using the non-parametric Wilcoxson's Rank Sum Tests and student T tests. All analysis was done in SAS for Windows Version 9.4. 38 (62%) patients were injected during morning clinic and 23 (38%) during afternoon clinic. There was no difference in gender, race, and age variables between morning and afternoon patients. 67% of the patients experienced increased pain following the initial injection. Higher pain score was more frequent following morning than afternoon injections (78% vs. 50%, p = .021). The 24 h post-injection pain level was also significantly higher in patients injected in the morning than afternoon (64% vs. 28%, p = .024). Performing BTA injections for migraine prevention during the morning was associated with significantly more treatment-related discomfort, both immediately and 24 h after injection. Scheduling diurnal active patients with stable circadian sleep/wake routine for afternoon BTA injections appears beneficial for decreasing treatment-related discomfort and potentially increase compliance to therapy.

Pharmaceutical industry interactions of psychiatric trainees from 20 European countries

Background:

Interactions between the pharmaceutical industry (PI) and psychiatrists have been under scrutiny recently, though there is little empirical evidence on the nature of the relationship and its intensity at psychiatry trainee level. We therefore studied the level of PI interactions and the underlying beliefs and attitudes in a large sample of European psychiatric trainees.

Methods:

One thousand four hundred and forty-four psychiatric trainees in 20 European countries were assessed cross-sectionally, with a 62-item questionnaire.

Results:

The total number of PI interactions in the preceding two months varied between countries, with least interactions in The Netherlands (M (Mean) = 0.92, SD = 1.44, range = 0–12) and most in Portugal (M = 19.06, SD = 17.44, range = 0–100). Trainees were more likely to believe that PI interactions have no impact on their own prescribing behaviour than that of other physicians (M = 3.30, SD = 1.26 vs. M = 2.39, SD = 1.06 on a 5-point Likert scale: 1 “completely disagree” to 5 “completely agree”). Assigning an educational role to the pharmaceutical industry was associated with more interactions and higher gift value (IRR (incidence rate ratio) = 1.21, 95%CI = 1.12–1.30 and OR = 1.18, 95%CI = 1.02–1.37).

Conclusions:

There are frequent interactions between European psychiatric trainees and the PI, with significant variation between countries. We identified several factors affecting this interaction, including attribution of an educational role to the PI. Creating alternative educational opportunities and specific training dedicated to PI interactions may therefore help to reduce the impact of the PI on psychiatric training.

Changes in Microbiome Confer Multigenerational Host Resistance after Sub-toxic Pesticide Exposure

The gut is a first point of contact with ingested xenobiotics, where chemicals are metabolized directly by the host or microbiota. Atrazine is a widely used pesticide, but the role of the microbiome metabolism of this xenobiotic and the impact on host responses is unclear. We exposed successive generations of the wasp Nasonia vitripennis to subtoxic levels of atrazine and observed changes in the structure and function of the gut microbiome that conveyed atrazine resistance. This microbiome-mediated resistance was maternally inherited and increased over successive generations, while also heightening the rate of host genome selection. The rare gut bacteria Serratia marcescens and Pseudomonas protegens contributed to atrazine metabolism. Both of these bacteria contain genes that are linked to atrazine degradation and were sufficient to confer resistance in experimental wasp populations. Thus, pesticide exposure causes functional, inherited changes in the microbiome that should be considered when assessing xenobiotic exposure and as potential countermeasures to toxicity.

More anxious than depressed: prevalence and correlates in a 15-nation study of anxiety disorders in people with type 2 diabetes mellitus

Background

Anxiety disorder, one of the highly disabling, prevalent and common mental disorders, is known to be more prevalent in persons with type 2 diabetes mellitus (T2DM) than the general population, and the comorbid presence of anxiety disorders is known to have an impact on the diabetes outcome and the quality of life. However, the information on the type of anxiety disorder and its prevalence in persons with T2DM is limited.

Aims

To assess the prevalence and correlates of anxiety disorder in people with type 2 diabetes in different countries.

Methods

People aged 18–65 years with diabetes and treated in outpatient settings were recruited in 15 countries and underwent a psychiatric interview with the Mini-International Neuropsychiatric Interview. Demographic and medical record data were collected.

Results

A total of 3170 people with type 2 diabetes (56.2% women; with mean (SD) duration of diabetes 10.01 (7.0) years) participated. The overall prevalence of anxiety disorders in type 2 diabetic persons was 18%; however, 2.8% of the study population had more than one type of anxiety disorder. The most prevalent anxiety disorders were generalised anxiety disorder (8.1%) and panic disorder (5.1%). Female gender, presence of diabetic complications, longer duration of diabetes and poorer glycaemic control (HbA1c levels) were significantly associated with comorbid anxiety disorder. A higher prevalence of anxiety disorders was observed in Ukraine, Saudi Arabia and Argentina with a lower prevalence in Bangladesh and India.

Conclusions

Our international study shows that people with type 2 diabetes have a high prevalence of anxiety disorders, especially women, those with diabetic complications, those with a longer duration of diabetes and poorer glycaemic control. Early identification and appropriate timely care of psychiatric problems of people with type 2 diabetes is warranted.

Interactive web-based visualization and sharing of phylogenetic trees using phylogeny.IO

Traditional static publication formats make visualization, exploration, and sharing of massive phylogenetic trees difficult. A phylogenetic study often involves hundreds of taxa, and the resulting tree has to be split across multiple journal pages, or be shrunk onto one, which jeopardizes legibility. Furthermore, additional data layers, such as species-specific information or time calibrations are often displayed in separate figures, making the entire picture difficult for readers to grasp. Web-based technologies, such as the Data Driven Document (D3) JavaScript library, were created to overcome such challenges by allowing interactive displays of complex data sets. The new phylogeny.IO web server (https://phylogeny.io) overcomes this issue by allowing users to easily import, annotate, and share interactive phylogenetic trees. It allows a range of static (e.g. such as shapes and colors) and dynamic (e.g. pop-up text and images) annotations. Annotated trees can be saved on the server for subsequent modification or they may be shared as IFrame HTML objects, easily embeddable in any web page. The principal goal of phylogeny.IO is not to produce publication-ready figures, but rather to provide a simple and intuitive annotation interface that allows easy and rapid sharing of figures in blogs, lecture notes, press releases, etc.

Functional and pharmacological analysis of agmatine administration in different cerebral ischemia animal models

Agmatine (AgM, 100 mg/kg i.p.) effect was tested in parallel at two animal models of cerebral ischemia - rat MCAO model (60'/24 h, 60'/48 h, 90'/24 h, 90'/48 h) and gerbil global ischemia (10') model, administrated 5 min after reperfusion. Aim was to evaluate AgM effect on functional outcome 24 and 48 h after MCAO on neurological and sensor-motor function, and coordination in rats. AgM administration significantly reduced infarct volume, improved neurological score and improved post-ischemic oxidative status. Results of behavioral tests (cylinder test, beam walking test, and adhesive removal test) have shown very effective functional recovery after AgM administration. Efficiency of AgM administration in gerbils was observed in forebrain cortex, striatum, hippocampus, and cerebellum at the level of each examined oxidative stress parameter (nitric oxide level, superoxide production, superoxide dismutase activity, and index of lipid peroxidation) measured in four different time points starting at 3 h up to 48 h after reperfusion. The highest levels were obtained 6 h after the insult. The most sensitive oxidative stress parameter to AgM was nitric oxide. Additionally, we performed pharmacological analysis of AgM on rat isolated common carotid arteries. The findings imply that mixed population of potassium channels located on the smooth muscle cells was involved in common carotid artery response to AgM, with predominance of inward rectifying K⁺ channels. In our comparative experimental approach, judged by behavioral, biochemical, as well as pharmacological data, the AgM administration showed an effective reduction of ischemic neurological damage and oxidative stress, hence indicating a direction towards improving post-stroke recovery.

Modal noise in an integrated photonic lantern fed diffraction-limited spectrograph

In an attempt to develop a streamlined astrophotonic instrument, we demonstrate the realization of an all-photonic device capable of both multimode to single mode conversion and spectral dispersion on an 8-m class telescope with efficient coupling. The device was a monolithic photonic spectrograph which combined an integrated photonic lantern and an efficient arrayed waveguide grating device. During on-sky testing, we discovered a previously unreported type of noise that made spectral extraction and calibration extremely difficult. The source of the noise was traced to a wavelength-dependent loss mechanism between the feed fiber's multimode near-field pattern and the modal acceptance profile of the integrated photonic lantern. Extensive modeling of the photonic components replicates the wavelength-dependent loss, and demonstrates an identical effect on the final spectral output. We outline that this could be mitigated by directly injecting into the integrated photonic lantern.

Demonstration of an efficient, photonic-based astronomical spectrograph on an 8-m telescope

We demonstrate for the first time an efficient, photonic-based astronomical spectrograph on the 8-m Subaru Telescope. An extreme adaptive optics system is combined with pupil apodiziation optics to efficiently inject light directly into a single-mode fiber, which feeds a compact cross-dispersed spectrograph based on array waveguide grating technology. The instrument currently offers a throughput of 5% from sky-to-detector which we outline could easily be upgraded to ∼ 13% (assuming a coupling efficiency of 50%). The isolated spectrograph throughput from the single-mode fiber to detector was 42% at 1550 nm. The coupling efficiency into the single-mode fiber was limited by the achievable Strehl ratio on a given night. A coupling efficiency of 47% has been achieved with ∼ 60% Strehl ratio on-sky to date. Improvements to the adaptive optics system will enable 90% Strehl ratio and a coupling of up to 67% eventually. This work demonstrates that the unique combination of advanced technologies enables the realization of a compact and highly efficient spectrograph, setting a precedent for future instrument design on very-large and extremely-large telescopes.

Psychiatry Trainee Burnout in the United Kingdom: The BoSS Study

Introduction

Burnout syndrome is defined by three domains: emotional exhaustion, cynicism and reduced professional efficacy. Junior doctors have a high susceptibility to burnout reflected in the high prevalence identified in previous work. This is a significant issue as burnout has measurable effects on work performance. There has been limited research conducted on burnout in psychiatry trainees in the United Kingdom.

Aim

This paper takes a step towards addressing this gap by extracting the data concerning UK psychiatric trainees collected in the international burnout syndrome study (BoSS), which aimed to assess the prevalence and contributing factors of burnout among psychiatric trainees from over 20 countries, and presenting the findings concerning UK trainees.

Method

Data collected included demographic data and information related to working hours, bullying, harassment and stalking, supervision, suicidal ideation, depression (PHQ−9), and a personality trait assessment. Burnout syndrome was measured using the Maslach burnout inventory (MBI-GS). A total of 3964 psychiatry trainees in the UK were invited, of which 1187 (30%) responded including 811 (20%) providing complete responses for MBI-GS.

Results

The mean age was 33 years, and 49.1% of respondents were male. Gender distribution of participants was the same as non-participants. Mean scores were 2.6 for exhaustion, 2.1 for cynicism and 4.5 for professional efficacy; and severe burnout was found in 309 (38%).

Conclusion

Three factors were positively associated with severe burnout: long working hours, lack of clinical supervision and not having regular time to rest.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Association study of MDR1 and 5-HT2C genetic polymorphisms and antipsychotic-induced metabolic disturbances in female patients with schizophrenia

The objective of this study was to determine the association of 5-HT2C (serotonin 2C receptor) and MDR1 (multidrug resistant protein) genetic polymorphisms and antipsychotic-induced metabolic abnormalities among female patients with DSM IV schizophrenia spectrum disorders. We have previously reported the associations of -759CT 5-HT2C and G2677T and C3435T MDR1 genetic polymorphisms and olanzapine/risperidone-induced weight gain in a similar sample of patients. Here, we included a total of 101 previously non-medicated female patients treated with olanzapine/risperidone over a 3-month period. The variables analyzed included fasting glucose, total cholesterol, low-density lipoprotein, high-density lipoprotein and triglyceride levels in blood, blood pressure and waist circumferences. We observed significant association of -759T 5-HT2C genetic variant and greater increase in waist circumference (P=0.03), fasting glucose level (P=0.046) and triglyceride level (P=0.045) in blood after a 3-month period. The 2677T and 3435T MDR1 genetic variants were significantly associated with the greater increase in fasting glucose level in blood when patients were using olanzapine (P<0.001 and P=0.028, respectively). Our data indicate a possible influence of -759CT 5-HT2C and MDR1 G2677T and C3435T MDR1 genetic polymorphisms on the development of metabolic abnormalities among female patients treated with olanzapine/risperidone.

Metabolic syndrome in female patients with schizophrenia treated with second generation antipsychotics: a 3-month follow-up

The objective of this study was to determine the occurrence of metabolic abnormalities among previously unmedicated female patients with Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition schizophrenia spectrum disorders and their associations with olanzapine and risperidone treatment. We analysed 94 female patients who were treated with olanzapine or risperidone in the period of 3 months. Analysed variables included fasting glucose, total cholesterol, low-density lipoprotein (LDL), high-density lipoproteins and triglycerides in blood, blood pressure (BP), waist and hip circumferences and body mass index (BMI). At baseline, 14 patients (15%) fulfilled criteria for metabolic syndrome. After 3 months of treatment, 25 patients (27%) fulfilled criteria for metabolic syndrome, and their baseline BMI was the only predictor for its development. Treatment with both antipsychotics was associated with significant increase in waist circumference. Positive family history of diabetes mellitus contributed to a significant greater increase in abdominal obesity, significant higher baseline levels and a borderline significant increase in fasting glucose among olanzapine-treated patients. Olanzapine admission was associated with a significant increase in LDL and risperidone with a significant increase in triglycerides. Metabolic abnormalities seem to be more prevalent in unmedicated female patients with schizophrenia spectrum disorders than expected based on results in general population (adjusted for age and sex). Olanzapine treatment might induce significant alterations in metabolic profiles, especially among patients with positive family history of diabetes, mostly by inducing abdominal obesity. The association of risperidone application and increase in triglyceride level still needs to be determined.

the Experience of art in Psychotherapy - How to see Angel in the Marble and Curve to set him Free?

Michelangelo said "I saw angel in the marble and carved until I set him free.", as he didn’t see himself creating something new, but unwrapping beauty that was already there. Art and psychotherapy have many things in common - both are based on relationships and sincerity, communicate through interpretation, creativity and imagination. Experience of art - as mode of learning about reality and one's inner world - can be incorporated into psychotherapy. Our Day hospital program includes psychodynamic analytic oriented group psychotherapy, psychoeducation, sociotherapy and art workshop. the latter implies patients’ artistic creation and visits to museums. It stimulates patients’ relationships with art and brings back a need for esthetic experience which can have protective and reparative role. Here we present several clinical vignettes, thus showing specific relations between psychotherapy and patients’ experience of art; and give an overview of psychiatric patients’ works stored in artistic collections (from Prizhorn until now), as well as art brut, and new psychotherapeutical technique - art therapy. Taking into account analytic and iconographic interpretations, we discuss their similarities and ask - what does a patient achieve by interpreting unconscious contents and what does interpretation of art mean to a recipient? Art and psychotherapy undoubtedly have an impact on us - they cause not only a direct physical reaction, but a sense of pursuit of meaning and contemplation leading to cognition. Every work of art leaves empty space for recipient to fill in. We believe this encourages an integrative process which is also aim of psychotherapy.

An experimental, non-uremic rabbit model of peritoneal dialysis

Peritoneal dialysis (PD) is a well established method of depuration in uremic patients. Standard dialysis solutions currently in use are not biocompatible with the peritoneal membrane. Studying effects of dialysate on peritoneal membrane in humans is still a challenge. There is no consensus on the ideal experimental model so far. We, therefore, wanted to develop a new experimental non-uremic rabbit model of peritoneal dialysis, which would be practical, easy to conduct, not too costly, and convenient to investigate the long-term effect of dialysis fluids. The study was done on 17 healthy Chinchilla male and female rabbits, anesthetized with Thiopental in a dose of 0.5 mg/kg body mass. A catheter, specially made from Tro-soluset (Troge Medical GMBH, Hamburg, Germany) infusion system, was then surgically inserted and tunneled from animals' abdomen to their neck. The planned experimental procedure was 4 weeks of peritoneal dialysate instillation. The presented non-uremic rabbit model of peritoneal dialysis is relatively inexpensive, does not require sophisticated technology and was well tolerated by the animals. Complications such as peritonitis, dialysis fluid leakage, constipation and catheter obstruction were negligible. This model is reproducible and can be used to analyze the effects of different dialysis solutions on the rabbit peritoneal membrane.

Sentinel Lymph Node Biopsy May Be Used to Support the Decision to Perform Modified Radical Neck Dissection in Differentiated Thyroid Carcinoma

BACKGROUND

The prognostic significance of lymph node metastases (LNM) in follicle cell-derived differentiated thyroid carcinoma (DTC) is still controversial. The management of cervical lymph nodes varies from "berry picking" to modified radical neck dissection (MRND). The incidence of LNM in papillary thyroid carcinoma varies from 27% to 80%. The importance of sentinel lymph node (SLN) biopsy for decisions about the surgical management of lymph nodes in DTC has been the subject of several previous studies.

PATIENTS AND METHODS

In 40 patients with DTC methylene blue dye was applied peritumorally. Both SLN and non-SLN in the lower third of the jugulo-carotid chain were dissected prior to total thyroidectomy and routine dissection of the central neck compartment and examined by frozen-section and standard histology. MRND was performed in 9 cases of LNM in the lateral neck compartment.

RESULTS

The SLN identification rate was 92.5%. Metastases in SLNs were revealed by frozen-section histology in 7 cases, leading to immediate MRND. The findings were confirmed on standard HE examination. In 2 false-negative cases SLN metastases were revealed on standard histology and MRND was performed 1 week later. The specificity of the method was 100%, sensitivity 77.7%, negative predictive value 94%, positive predictive value 100%, with overall accuracy of 95%.

CONCLUSION

Our results seem to imply that SLN biopsy in the jugulo-carotid chain using methylene blue dye mapping may be a feasible and valuable method for estimating lymph node status in the lateral neck compartment. It may be helpful in the detection of true-positive but nonpalpable lymph nodes, and in such cases may support the decision to perform MRND in patients with DTC.

[Principles of lymph node surgery in differentiated thyroid carcinoma]

Surgery is the initial therapy in differentiated thyroid carcinoma (DTC). The surgery is performed on organ of tumor origin and regional lymphatic basins. The aim of surgery in DTC is to eradicate all tumor foci, cure the most number of patients, reduce recurrence and mortality rate, and provide good quality of life. There is no doubt between oncologists that the surgery for thyroid carcinoma has no alternative. The extent of surgery is matter of actual controversies. It should be performed by well trained surgeons. Dissection of central and biopsy of supraclavicular and lower third of jugulo-carotid chain of neck lymph nodes is the integral part of surgery in DTC, together with total thyroidectomy. If lymph node metastases are found in jugulo-carotid chain, modified radical neck dissection, unilateral or bilateral is indicated. Dissection of mediastinal lymph nodes should be performed too in cases of involvement. The extent of primary surgery should be dictated by stage of disease and prognostic factors. The quality of surgery and incidence of complications depends prognostic factors, as well as on surgeon's skill and experience. That is why the surgeon is factor of prognosis in treatment of patients with DTC.