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Bats are important reservoirs and spreaders of pathogens. Giardia duodenalis is a globally important protozoan that infects humans and other mammals with considerable public health burden, particularly on the child development. Based on genetic variation and host specificity, G. duodenalis is categorized into eight genotypes/assemblages A-H. Assemblages A and B are widespread globally and are associated with human and animal disease. There is evidence of Giardia in the bat feces from diverse geographic regions, but the G. duodenalis assemblages are unknown, which is a key point for the One Health view. Here, we successfully amplified the BG/GDH/DIS3/HCMP2/HCMP3 targets of G. duodenalis from five bat species captured in the Brazilian Amazon biome revealing the presence of zoonotic G. duodenalis assemblages A and B in the feces of these flying mammals. Our study reveals that bats may play a role in transmission of zoonotic G. duodenalis , at least in this biome., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

Aquatic organisms are exposed to several compounds that occur in mixtures in the environment. Thus, it is important to investigate their impacts on organisms because these combined effects can be potentiated. Cobalt (Co) and nickel (Ni) are metals that occur in the environment and are used in human activities. To the best of our knowledge, there are no studies that investigated the combined effects of these metals on a freshwater Chlorophyceae. Therefore, this study analyzed the isolated and combined effects of Co and Ni in cell density, physiological and morphological parameters, reactive oxygen species (ROS), carbohydrates and photosynthetic parameters of the microalga Raphidocelis subcapitata. Data showed that Co affected the cell density from 0.25 mg Co L -1 ; the fluorescence of chlorophyll a (Chl a) (0.10 mg Co L -1 ); ROS production (0.50 mg Co L -1 ), total carbohydrates and efficiency of the oxygen evolving complex (OEC) at all tested concentrations; and the maximum quantum yield (Φ M ) from 0.50 mg Co L -1 . Ni exposure decreased ROS and cell density (0.35 mg Ni L -1 ); altered Chl a fluorescence and carbohydrates at all tested concentrations; and did not alter photosynthetic parameters. Regarding the Co-Ni mixtures, our data best fitted the concentration addition (CA) model and dose-ratio dependent (DR) deviation in which synergism was observed at low doses of Co and high doses of Ni and antagonism occurred at high doses of Co and low doses of Ni. The combined metals affected ROS production, carbohydrates, Φ M , OEC and morphological and physiological parameters., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Background: The parasite Giardia duodenalis infects a wide range of vertebrate hosts, including domestic and wild animals as well as humans. Giardia is genotyped into eight assemblages (A-H). Zoonotic assemblages A and B have already been identified in humans and wild and domestic animals (non-human primates and cats) from Brazilian Amazon and in the world. Due to its zoonotic/zooanthroponotic nature, surveillance initiatives and the definition of Giardia assemblages are important in order to characterise the epidemiological scenario and to implement further control measures., Objectives: Determine assemblages of G. duodenalis in sloths from the Brazilian Amazon Region., Methods: Faecal parasitological examination of sloths from Amazonas State. Polymerase chain reaction (PCR) targeting the beta giardin (BG), and genes from multilocus sequence typing (MLST) scheme, amplicon sequencing and phylogenetic analysis., Findings: Here, we identified, by microscopy, Giardia in two northern sloths (Bradypus tridactylus). These two samples were submitted to molecular assays and it was revealed that both were infected by G. duodenalis assemblage A. Phylogenetic analysis showed that they belong to assemblage A within sequences from humans and wild and domestic animals., Conclusion: Therefore, besides showing, by the first time, the current presence of this parasite in sloths, our findings reveals that this wild animal species would be part of the zoonotic/zooanthroponotic scenario of this parasite in the Brazilian Amazon.

Giardia is an ubiquitous protozoa that infect a broad range of vertebrate hosts, including domestic and wild animals as well as humans. Giardia duodenalis is one of the most common parasite in humans and mammals worldwide. Human giardiasis is highly prevalent in the countries that make up from Amazon. The identification of genotypes in humans and animals improves the understanding of transmission routes and the control strategies. Thus, we carried out a systematic review on Giardia in animals from Amazon region/South American, following the PRISMA guidelines. Studies up to September, 2022 were searched for in public database. A total of seven out of 432 articles were selected: four, two and one from Brazil, Colombia and Peru, respectively. Based on these articles it is seen that the G. duodenalis cosmopolitan assemblages A and B prevail within domestic and wild animals in the Amazon. Moreover, a Giardia microscopic screening in aquatic animals from this biome showed its prevalence among aquatic mammals including the endangered species Trichechus inunguis (manatee). Therefore, a yet not accessed number of susceptible hosts, new G. duodenalis assemblages and species can be occurring in this huge hotspot of biodiversity that is Amazon region., Competing Interests: Declaration of Competing Interest The authors declare no conflict of interest., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Metals occur simultaneously in the environment, and therefore it is important to know their toxicity and mechanism of action when associated with another metal. Furthermore, anthropogenic actions increase their concentrations in the environment where they can interact and undergo transformations that can even increase their toxicity. This study aimed to evaluate the effects of cadmium (Cd) and cobalt (Co), isolated and combined, on the microalgae Raphidocelis subcapitata. Regarding the toxicity of isolated metals, the IC 50 96 h was 0.08 mg L -1 of Cd and 0.16 mg L -1 of Co. Cell density decreased at all concentrations of the Cd tested. The parameters related to cell size, cell complexity and mean cell chlorophyll a (Chl a) fluorescence were significantly affected by both metals. According to species sensitivity curves (SSD), the microalgae R. subcapitata was the second most sensitive organism to Co exposure and the tenth concerning Cd. Metal mixture data were best fitted to the concentration addition (CA) model and dose-ratio dependence (DR) deviation, showing synergism at high concentrations of Co and low concentrations of Cd. Besides that, antagonism was observed at low concentrations of Co and high concentrations of Cd. Photosynthetic performance, assessed by maximum quantum yield (Φ M ) and oxygen evolving complex (OEC), presented antagonism effects for both analyzed parameters. Thus, the mixture of Cd and Co showed synergistic and antagonistic interactions for the parameters analyzed in R. Subcapitata, indicating the importance of understanding the mechanisms of toxicity of metal mixtures in phytoplankton., (Copyright © 2022. Published by Elsevier B.V.)

Background: Giardia duodenalis is a protozoan parasite that infects humans and other mammals and causes giardiasis worldwide. Giardia is genotyped into eight assemblages (A-H), with assemblages A and B considered zoonotic., Objectives: The aim of this study was to determine the assemblages of G. duodenalis from individuals living in rural and urban areas of the Amazonas State., Methods: 103 human faecal specimens microscopically positive for the presence of Giardia obtained from four municipalities in Amazonas and four animal faecal specimens were genotyped based on the sequences of two genes, triosephosphate isomerase (TPI) and β-giardin (BG)., Findings: In humans, assemblage A was the most represented with the identification of sub-assemblages AI, AII and AIII based on BG and sub-assemblages AI and AII based on TPI. Similarly, there is a diversity of sub-assemblage B considering BG (B and BIII) and TPI (B, BIII and BIV). In addition, we characterised homogeneous and heterogeneous genotypes comprising assemblages/sub-assemblages A and B in individuals from urban and rural areas. Here, for the first time, it was genotyped Giardia that infects animals from the Brazilian Amazon region. We identified sub-assemblage AI in one Ateles paniscus and two Felis catus and sub-assemblage BIV in one Lagothrix cana., Main Conclusions: Therefore, humans and animals from the urban and rural Amazon share Giardia genotypes belonging to assemblages A and B, which are found in cosmopolitan regions around the world.

Background: Studies have demonstrated the positive effects of physical activity on cardiovascular risk factors. Longitudinal studies using modeled trajectories are necessary to understand patterns of physical activity and association with cardiovascular risk factors. Objective: To analyze the association between sports practice in young people and current physical activity with the trajectory of cardiovascular risk factors in workers at a public hospital. Methods: Four hundred and seventeen workers was followed for four years reporting Physical Activity, health status, lifestyle behaviors and socio-demographic characteristics. Group-based trajectory modeling identified the trajectories of PA and associations with time-stable and time-varying covariates. We considered a range of sociodemographic and health and lifestyle factors as potential covariates. Results: The results shows the association between participation in sports activities in youth and current physical activity and trajectories of cardiovascular risk, adjusted for sex and age ( p < 0.05). Adults who reported having played sports in their youth and are currently active have a lower risk of having a history of obesity and low HDL-c than workers who did not play sports in their youth and are currently sedentary 0.690 (0.565-0.844) obesity, 0.647 (0.500-0.837) low HDL-c. Conclusion: The practice of sports in youth and current physical activity is a protective factor against the trajectory of obesity and low HDL-c, mainly in female workers. Programs to encourage the practice of physical activity should be carried out in order to reduce cardiovascular risk factors and prevent chronic diseases in workers., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Marques Elias, Ieker, Reis, Stabelini Neto, Sasaki, Lopes, Costa and Rinaldi.)

Risk behaviors and signs of burnout are associated with substantial health losses and university dropouts. Physical activity can be an effective approach to reduce these factors. The objective of this study was to analyze aspects related to health behaviors, physical activity, and signs of burnout in university students and their association with physical activity. The probabilistic cluster sample consisted of 3,578 regularly enrolled undergraduate students from UFPR in Curitiba, based on a population sample of 24,032 university students. The students completed the MBI-SS and NCHA II instruments . Descriptive statistics were used to identify demographic indicators and characteristics of the university environment. For the proportion of subjects with respective confidence intervals ( CI = 95%), contingency tables involving the chi-square test (χ 2 ) were used. The prevalence of signs of burnout was estimated in punctual proportions accompanied by the respective confidence intervals ( CI = 95%). To analyze the associations between the independent variables and signs of burnout , the Hierarchical Logistic Regression was used through an analysis adjusted by the other independent variables involved in the models ( CI = 95%). Results showed that the prevalence of individuals who showed signs of burnout was 40.4%. The hierarchical multiple regression model pointed to: female sex (OR = 1.30; 1.11-1.51); age between 20-24 years (OR = 1.51; 1.25-1.83); and 25-29 years (OR = 1.69; 1.27-2.24); being single (OR = 2.67; 1.01-7.10); presenting regular/poor health perception (OR = 1.59; 1.13-2.22), belonging to Human Sciences courses (OR = 1.37; 1.14-1.64); attending 2nd or 3rd year (OR = 1.34; 1.12-1.61); poor academic performance (OR = 5.35; 4.11-6.96); mean (OR = 2.08; 1.78-2.43). We conclude that academics showed a high prevalence of health risk behaviors and correlate and diagnose emotional problems and signs of burnout . Signs of burnout were significantly associated with the practice of physical activity in its three dimensions; however, in the adjusted analysis for demographic indicators, the characteristics of the university environment, and health behaviors, physical activity was not significant for the model., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Souza, Ricardo Guilherme, Elias, dos Reis, Garbin de Souza, Robert Ferrer, dos Santos and Osiecki.)

Background: The appearance of anthelmintic resistance has made it difficult to control verminosis in sheep, leading to increased research to find alternative nematode control. The use of homeopathy in veterinary medicine has been studied as an alternative for the treatment and control of some diseases. In this study, ewes received an anti-parasitic homeopathic complex medicine during the critical peripartum period of increased susceptibility to nematodes., Methods: Three randomized groups containing 16 animals each were assigned as follows: 'H10' received 10 g homeopathic complex added to concentrated food per day; 'H20' received 20 g homeopathic complex added to concentrated food per day; 'C' (control group) did not receive a homeopathic complex. Animals were tested to evaluate the effect of homeopathy on several health parameters during a period of 110 days., Results: The parasite that prevailed in the copro-cultures of both treatments throughout the experiment was Haemonchus contortus (78.26%). Packed cell volume averages did not present statistically significant differences between the treatments (24.5, 24.4 and 23.9% to C, H10 and H20, respectively; p  < 0.05). For total white cell count, lower mean values ( ±  standard error of mean) were observed for the H20 treatment (5,490.9 ± 0.02/µL; p  < 0.05), whereas the H10 (5,919.4 ± 0.02/µL) and control (6,098.5 ± 0.02/µL) presented higher and similar averages ( p  > 0.05). The values for erythrocytes, monocytes, and lymphocytes did not show differences between treatments ( p  > 0.05). Body weight was greater in the H10-treated animals compared with control. For the fecal egg count (FEC) of Trichostrongylidae and Strongyloides spp., respectively, the averages of the H20 treatment (1,523.0 and 30.6) were not different from control (1,616.0 and 31.6) and H10 (1,038.0 and 27.6); for Trichostrongylidae , however, H10 presented a lower FEC than the control ( p  = 0.02). For Cooperia, H10- and H20-treated animals showed FEC reductions of 97% and 98%, respectively., Conclusions: H20 treatment in peripartum sheep resulted in greater body weight and lower leukocyte count. H10 was associated with lower FEC for Trichostrongylidae . Both H10 and H20 justify a label of 'effective anthelmintic' for Cooperia ., Competing Interests: None declared., (The Faculty of Homeopathy.)

A new series of silver compounds could be of interest on designing new drugs for the treatment of leishmaniasis. The compounds [Ag(phen)(imzt)]NO 3 (1), [Ag(phen)(imzt)]CF 3 SO 3 (2), [Ag(phen) 2 ](BF 4 )·H 2 O (3), [Ag 2 (imzt) 6 ](NO 3 ) 2 (4), and imzt have been synthesized and evaluated in vitro for antileishmanial activity against Leishmania. (L.) amazonensis (La) and L. (L.) chagasi (Lc), and two of them were selected for in vivo studies. In addition to investigating the action on Leishmania, their effects on the hydrogen peroxide production and cysteine protease inhibition have also been investigated. As for antileishmanial activity, compound (4) was the most potent against promastigote and amastigote forms of La (IC 50  = 4.67 and 1.88 μM, respectively) and Lc (IC 50  = 9.35 and 8.05 μM, respectively); and comparable to that of amphotericin B, reference drug. Beside showing excellent activity, it also showed a low toxicity. In the in vivo context, compound (4) reduced the number of amastigotes in the liver and spleen when compared to the untreated group. In evaluating the effect of the compounds on Leishmania, the level of hydrogen peroxide production was maintained between the lag and log phases; however, in the treatment with compound (4) it was possible to observe a reduction of 25.44 and 49.13%, respectively, in the hydrogen peroxide rates when compared to the lag and log phases. It was noticed that the presence of a nitrate ion and imzt in compound (4) was important for the modulation of the antileishmanial activity. Thus, this compound can represent a potentially new drug for the treatment of leishmaniasis.

Objectives/hypothesis: To present an overview of the barriers to the implementation of clinical practice guidelines (CPGs) in thyroid cancer management and to introduce a computer-based clinical support system., Data Sources: PubMed., Review Methods: A review of studies on adherence to CPGs was conducted., Results: Awareness and adoption of CPGs is low in thyroid cancer management. Barriers to implementation include unfamiliarity with the CPGs and financial concerns. Effective interventions to improve adherence are possible, especially when they are readily accessible at the point of care delivery. Computerized clinical support systems show particular promise. The authors introduce the clinical decision making modules (CDMMs) of the Thyroid Cancer Care Collaborative, a thyroid cancer-specific electronic health record. These computer-based modules can assist clinicians with implementation of these recommendations in clinical practice., Conclusion: Computer-based support systems can help clinicians understand and adopt the thyroid cancer CPGs. By integrating patient characteristics and guidelines at the point of care delivery, the CDMMs can improve adherence to the guidelines and help clinicians provide high-quality, evidence-based, and individualized patient care in the management of differentiated thyroid cancer. Laryngoscope, 126:2640-2645, 2016., (© 2016 The American Laryngological, Rhinological and Otological Society, Inc.)

Objective: The dramatic increase in papillary thyroid carcinoma (PTC) is primarily a result of early diagnosis of small cancers. Active surveillance is a promising management strategy for papillary thyroid microcarcinomas (PTMCs). However, as this management strategy gains traction in the U.S., it is imperative that patients and clinicians be properly educated, patients be followed for life, and appropriate tools be identified to implement the strategy., Methods: We review previous active surveillance studies and the parameters used to identify patients who are good candidates for active surveillance. We also review some of the challenges to implementing active surveillance protocols in the U.S. and discuss how these might be addressed., Results: Trials of active surveillance support nonsurgical management as a viable and safe management strategy. However, numerous challenges exist, including the need for adherence to protocols, education of patients and physicians, and awareness of the impact of this strategy on patient psychology and quality of life. The Thyroid Cancer Care Collaborative (TCCC) is a portable record keeping system that can manage a mobile patient population undergoing active surveillance., Conclusion: With proper patient selection, organization, and patient support, active surveillance has the potential to be a long-term management strategy for select patients with PTMC. In order to address the challenges and opportunities for this approach to be successfully implemented in the U.S., it will be necessary to consider psychological and quality of life, cultural differences, and the patient's clinical status.

Background: Our surgical approach describes a bipaddled radial forearm free flap (RFFF) for closure of chronic tracheoesophageal fistulae (TEF) in patients who underwent total laryngectomy. The desired functional results were achieved., Methods: Eight patients underwent the procedure. The surgical approach includes exposure and resection of the fistula tract, and a bipaddled RFFF transfer. Key surgical maneuvers include: circumferential dissection and mobilization of the trachea; partial sternal resection in select cases; inset of flap's distal paddle into the anterior esophageal wall; and inset of the proximal skin paddle to the posterior tracheal wall and cervical skin., Results: Successful reconstruction of all 8 cases was done to restore a normal diet and a widely patent tracheal opening. One patient developed a delayed esophageal stricture, which was successfully managed with home dilation., Conclusion: Several TEF treatment approaches have been reported. Our 87.5% esophageal lumen preservation success rate, reestablishment of adequate airway, and uncomplicated postoperative courses demonstrates the reliability of this surgical approach. © 2015 Wiley Periodicals, Inc. Head Neck 38: E172-E178, 2016., (© 2015 Wiley Periodicals, Inc.)

Extranodal extension (ENE) is an indicator of poor prognosis in well-differentiated thyroid cancer (WDTC). We have demonstrated that extrathyroidal extension (ETE) predicts ENE in patients with positive lymph nodes, indicating concordance between primary tumor and lymph node biology. In an effort to determine if there were other histologic features of the primary tumors that indicated an aggressive biology, we examined a subset of patients with intrathyroidal (T1/T2) disease whose lymph nodes had ENE. A review was conducted from January 2004 to March 2013. The histologic features of ETE-negative/ENE-positive tumors (group A, 12 cases) were compared with a random sample of ETE-negative/ENE-negative node-positive patients (group B, 27 cases). Cases were reviewed for size, capsule presence, infiltration, sclerosis, lymphocytic thyroiditis (LT), psammoma bodies, lymphovascular invasion (LVI), perineural invasion (PNI), architecture/cytomorphology, and focality. Size was compared using the Mann-Whitney test, while the remaining features were compared using a Fischer exact test. The breakdown of pathologic features of groups A/B were as follows: 2.28 cm/1.46 cm mean tumor size, 90 %/67 % unencapsulated, 100 %/89 % infiltrative, 100 %/89 % sclerotic, 60 %/52 % LT, 30 %/59 % positive psammoma bodies, 0 %/11 % LVI, 0 %/4 % PNI, 90 %/96 % classic architecture, 50 %/44 % multifocal. Neither size (p = 0.072) nor the other nine histologic features examined reached statistical significance. None of the histologic features appeared to significantly predict ENE. Further examination of intrathyroidal tumors at a molecular level is necessary to determine if there are any identifiable features of intrathyroidal tumors that predict ENE and thus a more aggressive phenotype.

Background: Appropriate management of well-differentiated thyroid cancer requires treating clinicians to have access to critical elements of the patient's presentation, surgical management, postoperative course, and pathologic assessment. Electronic health records (EHRs) provide an effective method for the storage and transmission of patient information, although most commercially available EHRs are not intended to be disease-specific. In addition, there are significant challenges for the sharing of relevant clinical information when providers involved in the care of a patient with thyroid cancer are not connected by a common EHR. In 2012, the American Thyroid Association (ATA) defined the critical elements for optimal interclinician communication in a position paper entitled, "The Essential Elements of Interdisciplinary Communication of Perioperative Information for Patients Undergoing Thyroid Cancer Surgery.", Summary: We present a field-by-field comparison of the ATA's essential elements as applied to three contemporary electronic reporting systems: the Thyroid Surgery e-Form from Memorial Sloan-Kettering Cancer Center (MSKCC), the Alberta WebSMR from the University of Calgary, and the Thyroid Cancer Care Collaborative (TCCC). The MSKCC e-form fulfills 21 of 32 intraoperative fields and includes an additional 14 fields not specifically mentioned in the ATA's report. The Alberta WebSMR fulfills 45 of 82 preoperative and intraoperative fields outlined by the ATA and includes 13 additional fields. The TCCC fulfills 117 of 120 fields outlined by the ATA and includes 23 additional fields., Conclusions: Effective management of thyroid cancer is a highly collaborative, multidisciplinary effort. The patient information that factors into clinical decisions about thyroid cancer is complex. For these reasons, EHRs are particularly favorable for the management of patients with thyroid cancer. The MSKCC Thyroid Surgery e-Form, the Alberta WebSMR, and the TCCC each meet all of the general recommendations for effective reporting of the specific domains that they cover in the management of thyroid cancer, as recommended by the ATA. However, the TCCC format is the most comprehensive. The TCCC is a new Web-based disease-specific database to enhance communication of patient information between clinicians in a Health Insurance Portability and Accountability Act (HIPAA)-compliant manner. We believe the easy-to-use TCCC format will enhance clinician communication while providing portability of thyroid cancer information for patients.

Background: The use of high-resolution ultrasound (US) imaging is a mainstay of the initial evaluation and long-term management of thyroid nodules and thyroid cancer. To fully capitalize on the diagnostic capabilities of a US examination in the context of thyroid disease, many clinicians consider it desirable to establish a universal format and standard of US reporting. The goals of this interdisciplinary consensus statement are twofold. First, to create a standardized set of US features to characterize thyroid nodules and cervical lymph nodes accurately, and second, to create a standardized system for tracking sequential changes in the US examination of thyroid nodules and cervical lymph nodes for the purpose of determining risk of malignancy., Summary: The Thyroid, Head and Neck Cancer (THANC) Foundation convened a panel of nine specialists from a variety of medical disciplines that are actively involved in the diagnosis and treatment of thyroid nodules and thyroid cancer. Consensus was achieved on the following topics: US evaluation of the thyroid gland, US evaluation of thyroid nodules, US evaluation of cervical lymph nodes, US-guided fine needle aspiration (FNA) of thyroid nodules, and US-guided FNA of cervical lymph nodes., Conclusion: We propose that this statement represents a consensus within a multidisciplinary team on the salient and essential elements of a comprehensive and clinically significant thyroid and neck US report with regards to content, terminology, and organization. This reporting protocol supplements previous US performance guidelines by not only capturing categories of findings that may have important clinical implications, but also delineating findings that are clinically relevant within those categories as specifically as possible. Additionally, we have included the specific features of diagnostic and therapeutic interventions that have not been previously addressed.

Objective: Foci of increased radioactive iodine (RAI) uptake in the thyroid bed following total thyroidectomy (TT) indicate residual thyroid tissue that may be benign or malignant. The use of postoperative RAI therapy in the form of remnant ablation, adjuvant therapy, or therapeutic intervention is often followed by a posttherapy scan. Our objective is to improve the clinician's understanding of the anatomic complexity of this region and to enhance the interpretation of postoperative scans., Methods: We conducted a comprehensive review of the literature evaluating RAI uptake in the central compartment following thyroid cancer treatment and literature related to anatomic nuances associated with this region. Thirty-eight articles were selected., Results: Through extensive surgical experience and a literature review, we identified the 5 most important anatomic considerations for clinicians to understand in the interpretation of foci of increased RAI uptake in the thyroid bed on a diagnostic scan: 1) residual benign thyroid tissue at the level of the posterior thyroid ligament, 2) residual benign thyroid tissue at the superior portion of the pyramidal lobe and/or superior poles of the lateral thyroid lobes, 3) residual benign thyroid tissue that was left attached to a parathyroid gland in order to preserve its vascularity, 4) ectopic benign thyroid tissue, and 5) malignant thyroid tissue that has metastasized to central compartment nodes or invaded visceral structures., Conclusion: By correlating anatomic description, medical illustrations, surgical photos, and scans, we have attempted to clarify the reasons for foci of increased uptake following TT to improve the clinician's understanding of the anatomic complexity of this region.

Background: Prophylactic central neck dissection (PCND) for papillary thyroid cancer (PTC) is controversial. Recent publications suggest that the number and size of nodes and the presence of extranodal extension (ENE) are important features for risk stratification of lymph node metastases. We analyzed these features in clinically unapparent nodes that would not otherwise be removed. We also investigated the impact of surgeon experience on the ability to detect metastatic lymph nodes intraoperatively., Methods: Forty-seven patients with well-differentiated PTC, with no preoperative evidence of central metastases, were included in this study. Intraoperatively, clinically apparent disease was determined by inspection and palpation by the senior surgeon and a fellow/senior resident, and recorded in a blinded fashion. Rate of occult metastases based on intraoperative evaluation were tabulated for each group of surgeons. Histopathologic features of occult nodes were analyzed to determine what clinicians would be missing by foregoing a PCND, and how that would have impacted the patient management., Results: The rate of occult metastases, based on senior surgeon assessment, was 26%, and did not differ significantly from fellow/senior resident assessment. The level of agreement between these two surgeon groups was moderate (k=0.665). Analysis of the false negative cases revealed that the size of the largest undetected node ranged from 0.1 to 1.3 cm; 36% of patients with occult metastases demonstrated five or more positive nodes, and 27% showed ENE., Discussion: Clinical assessment based on intraoperative inspection and palpation had poor sensitivity and specificity in identifying metastatic central nodes, regardless of the level of experience of the surgeon. There was moderate agreement between surgeons of different experience levels. Sensitivity improved significantly with larger size of positive nodes, but not with the presence of multiple positive nodes or presence of ENE. In foregoing PCND in this patient population, our results suggest that treating clinicians miss potentially virulent disease with a large number of occult positive central nodes and occult nodes with ENE. This is the first report to address the pathologic features of clinically nonevident central nodes showing a high incidence of clinically relevant, adverse histologic features, as well as the impact of surgeon experience in performing the important intraoperative determination of whether there are clinically evident nodes that require removal.

This paper considers the implementation of a current control method for switched reluctance motors (SRMs) and presents a novel approach to the accurate on-line modeling of an SRM drive. A simple autotuning technique for the SRM drives using a PWM controller is considered. Furthermore, conventional PI control and Internal Model Control (IMC) are considered to validate this method and present corresponding robust control analysis for the process. The control structures are comparatively analyzed using standard robustness measures for stability and performance. The proposed PWM controller is simulated and a hardware prototype is then implemented using digital signal processor control to evaluate the method using a 12/8, three-phase SRM. The experimental results of the SRM drive model validates the performance of the current loop.