Performance of a multigene genomic classifier and clinical parameters in predicting malignancy in a Southeast Asian cohort of patients with cytologically indeterminate thyroid nodules

BACKGROUND

Most thyroid nodules are benign. It is important to determine the likelihood of malignancy in such nodules to avoid unnecessary surgery. The primary objective of this study was to characterize the genetic landscape and the performance of a multigene genomic classifier in fine-needle aspiration (FNA) biopsies of cytologically indeterminate thyroid nodules in a Southeast Asian cohort. The secondary objective was to assess the predictive contribution of clinical characteristics to thyroid malignancy.

METHODS

This prospective, multicenter, blinded study included 132 patients with 134 nodules. Molecular testing (MT) with ThyroSeq v3 was performed on clinical or ex-vivo FNA samples. Centralized pathology review also was performed.

RESULTS

Of 134 nodules, consisting of 61% Bethesda category III, 20% category IV, and 19% category V cytology, and 56% were histologically malignant. ThyroSeq yielded negative results in 37.3% of all FNA samples and in 42% of Bethesda category III-IV cytology nodules. Most positive samples had RAS-like (41.7%), followed by BRAF-like (22.6%), and high-risk (17.9%) alterations. Compared with North American patients, the authors observed a higher proportion of RAS-like mutations, specifically NRAS, in Bethesda categories III and IV and more BRAF-like mutations in Bethesda category III. The test had sensitivity, specificity, negative predictive value, and positive predictive value of 89.6%, 73.7%, 84.0%, and 82.1%, respectively. The risk of malignancy was predicted by positive MT and high-suspicion ultrasound characteristics according to American Thyroid Association criteria.

CONCLUSIONS

Even in the current Southeast Asian cohort with nodules that had a high pretest cancer probability, MT could lead to potential avoidance of diagnostic surgery in 42% of patients with Bethesda category III-IV nodules. MT positivity was a stronger predictor of malignancy than clinical parameters.

Source apportionment and ozone formation mechanism of VOCs considering photochemical loss in Guangzhou, China

Understanding the sources and impact of volatile organic compounds (VOCs) on ozone formation is challenging when the traditional method does not account for their photochemical loss. In this study, online monitoring of 56 VOCs was carried out in summer and autumn during high ozone pollution episodes. The photochemical age method was used to evaluate the atmospheric chemical loss of VOCs and to analyze the effects on characteristics, sources, and ozone formation of VOC components. The initial concentrations during daytime were 5.12 ppbv and 4.49 ppbv higher than the observed concentrations in the summer and autumn, respectively. The positive matrix factorization (PMF) model identified 5 major emission sources. However, the omission of the chemical loss of VOCs led to underestimating the contributions of sources associated with highly reactive VOC components, such as those produced by biogenic emissions and solvent usage. Conversely it resulted in overestimating the contributions from VOC components with lower chemical activity such as liquefied petroleum gas (LPG) usage, vehicle emissions, and gasoline evaporation. Furthermore, the estimation of ozone formation may be underestimated when the atmospheric photochemical loss is not taken into account. The ozone formation potential (OFP) method and propylene-equivalent concentration method both underestimated ozone formation by 53.24 ppbv and 47.25 ppbc, respectively, in the summer, and by 40.34 ppbv and 26.37 ppbc, respectively, in the autumn. The determination of the ozone formation regime based on VOC chemical loss was more acceptable. In the summer, the ozone formation regime changed from the VOC-limited regime to the VOC-NOx transition regime, while in the autumn, the ozone formation regime changed from the strong VOC-limited regime to the weak VOC-limited regime. To obtain more thorough and precise conclusions, further monitoring and analysis studies will be conducted in the near future on a wider variety of VOC species such as oxygenated VOCs (OVOCs).

The impact of lymph node ratio on disease recurrence in papillary thyroid microcarcinoma

INTRODUCTION

Lymph node (LN) metastases in papillary thyroid microcarcinomas (microPTCs) are common. The lymph node ratio (LNR) has been proposed as a risk factor for recurrence in papillary thyroid cancer. However, its relevance in microPTC is undetermined.

METHODS

Patients who underwent resection of their microPTC with concomitant LN clearance between 2005 and 2018 were identified. The LNR was calculated as the ratio of positive LNs to the total number of LNs.

RESULTS

Data on 50 patients (36 female [72%]; median age 47 years [range: 19-84]) who underwent LN clearance (28 central [56%] vs 22 central + lateral [44%]) were analysed. Positive LNs were found in over two-thirds of the patients (n = 34; 68%). After a median follow-up of 61 months, 14 patients (28%) had developed recurrence. Positive LNs were not found to impact recurrence-free survival; extranodal extension and an LNR ≥ 0.26 were found to significantly increase the risk of recurrence on unadjusted analyses (p < 0.05).

CONCLUSIONS

LN metastases are frequent among patients with microPTC. A higher LNR seems to be associated with recurrence. Additional studies are needed to further clarify these findings and to assess the possible role of LNR in treatment and surveillance.

The efficacy of adjuvant radioactive iodine after reoperation in patients with persistent or recurrent differentiated thyroid cancer: a systematic review

OBJECTIVE

The effectiveness of adjuvant radioiodine (RAI) after reoperation in patients with persistent or recurrent differentiated thyroid cancer (DTC) is controversial. Although various organizations recognize that strong evidence for the use of RAI is lacking, they continue to recommend the use of adjuvant RAI therapy for select groups of patients. This is concerning as RAI therapy has potential side effects such as gastrointestinal symptoms, bone marrow suppression, and gonadal damage.

METHODS

Four electronic databases were systematically searched for randomized trials or observational studies that examined the outcomes of adjuvant RAI after reoperation for recurrent DTC, among patients of any age. The baseline characteristics, treatment response, disease progression, and overall survival of these studies were synthesized and reported. A meta-analysis of the use of RAI on progression-free survival was also performed.

RESULTS

Six observational studies, comprising a combined cohort of 437 patients who underwent reoperation, were included from 1212 records. Adjuvant RAI after reoperation in recurrent DTC was not associated with longer progression-free or overall survival. There was also no association of RAI with excellent structural or biochemical treatment response, lower thyroglobulin levels, nor a lower rate of second recurrence or distant metastases.

CONCLUSIONS

Adjuvant RAI after reoperation in recurrent DTC was not associated with improved cancer or treatment-related outcomes. However, as the included studies were of inadequate quality, there is an urgent need for randomized trials and well-analyzed cohort studies. Physicians should exercise clinical judgment to prescribe adjuvant RAI for only selected, high-risk patients.

2021 Asia-Pacific Graves' Disease Consortium Survey of Clinical Practice Patterns in the Management of Graves' Disease

AIM

Although Graves' disease (GD) is common in endocrine practices worldwide, global differences in diagnosis and management remain. We sought to assess the current practices for GD in countries across Asia and the Pacific (APAC), and to compare these with previously published surveys from North America and Europe.

METHODS

A web-based survey on GD management was conducted on practicing clinicians. Responses from 542 clinicians were received and subsequently analysed and compared to outcomes from similar surveys from other regions.

RESULTS

A total of 542 respondents participated in the survey, 515 (95%) of whom completed all sections. Of these, 86% were medical specialists, 11% surgeons, and 3% nuclear medicine physicians. In addition to serum thyroid-stimulating hormone (TSH) and free thyroxine assays, most respondents would request TSH-receptor autoantibody (TRAb) measurement (68%) during initial work-up. Thyroid ultrasound is requested by about half of respondents (53%), while the use of nuclear medicine scans is limited. The preferred first-line treatment is anti-thyroid drug (ATD) therapy (79%) with methimazole (MMI) or carbimazole (CBZ), followed by radioiodine (RAI; 19%) and surgery (2%). In case of surgery, one-third of respondents would opt for a subtotal rather than a total thyroidectomy. In case of mild Graves orbitopathy (GO), ATDs (67%) remains the preferred treatment, but a larger proportion of clinicians prefer surgery (20%). For a patient with intention to conceive, the preferred treatment pattern remained unchanged, although propylthiouracil (PTU) became the preferred ATD-agent during the first trimester. In comparison to European and American practices, marked differences were noted in the relatively infrequent usage of nuclear medicine scans and the overall higher use of a ATDs and β-blockers and adjunctive ATD-treatment during RAI in the APAC-group.

CONCLUSION

Although regional differences regarding the diagnosis and management of GD are apparent in this first pan-Asia-Pacific survey, this study reveals the overall approach to the management of this disease in Asia-Pacific generally tends to fall between the trends appreciated in the American and European cohorts.

Stable thyroid function despite regular use of povidone-iodine throat spray for SARS-CoV-2 prophylaxis

BACKGROUND

It is unclear whether unintentional ingestion of povidone-iodine following its application to the oropharyngeal space could affect thyroid function.

OBJECTIVE

To examine thyroid function among individuals who regularly apply povidone-iodine throat spray for SARS-CoV-2 prophylaxis.

METHODS

We designed a case-control study to compare thyroid function among participants who received povidone-iodine throat spray three times a day for 42 days ('cases') and those who received vitamin C ('controls'). Thyroid function was assessed by profiling serum TSH, free T3, and free T4; iodine status was estimated using serum thyroglobulin level, while infection status was determined by measuring anti-SARS-CoV-2 antibody against the nucleocapsid antigen. All measurements were performed in pairs, at baseline and 42 days later. Pre-post changes in thyroid function were compared between groups, before and after stratification according to baseline TSH quartiles.

RESULTS

A total of 177 men (117 cases and 60 controls) (mean age, 32.2 years) were included. Despite comparable demographics and clinical profiles, no clinically or statistically significant differences were observed in thyroid indices between 'cases' and 'controls' before and after stratification according to TSH quartiles. None of the participants developed symptomatic hypo- or hyperthyroidism throughout the study. Post-hoc analysis did not reveal differences in thyroid function according to infection status.

CONCLUSIONS

Data from this study support the overall safety of povidone-iodine use in the oropharyngeal space for SARS-CoV-2 prophylaxis among individuals with normal thyroid function and subclinical thyroid disease.

Expect the Unexpected: Artifacts From Lodged 124I Capsule in Esophagus on PET/CT

ABSTRACT

A 61-year-old woman with well-differentiated thyroid cancer underwent 124I-PET/CT imaging. A 124I capsule was administered orally, and the patient was imaged 90 minutes after from the skull vertex to feet. The 124I capsule was unexpectedly lodged in the esophagus. We illustrate attenuation and scatter correction artifacts from 124I capsule unexpectedly lodged in the esophagus and the usefulness of nonattenuation correction images in such circumstances. This also highlights the importance of drinking adequate amounts of water following the ingestion of iodine capsules (123I, 124I, or 131I) to reduce the resulting radiation dose to the esophagus.

The efficacy and safety of cinacalcet in primary hyperparathyroidism: a systematic review and meta-analysis of randomized controlled trials and cohort studies

Cinacalcet, a positive allosteric modulator of the calcium sensing receptor (CaSR) reduces parathyroid hormone (PTH) secretion by increasing the sensitivity of the CaSR on parathyroid cells. We conducted a systematic review and meta-analysis on the safety and efficacy of cinacalcet in Primary Hyperparathyroidism (PHPT). MEDLINE, Embase, BIOSIS, and the Cochrane Library were searched for published articles (from database inception to Sept 2020). All double-blind RCTs and cohort studies that reported data on the efficacy and safety of cinacalcet therapy in individuals ≥ 18 with PHPT were included. Random effect meta-analysis was performed to estimate the efficacy of cinacalcet in lowering serum calcium and PTH levels compared with placebo. 4 RCTs (177 participants) and 17 cohort studies (763 participants) were eligible for final analysis. Pooled results from the RCTs suggest that, when compared to placebo and administered for up to 28 weeks, cinacalcet normalizes serum calcium (≤ 10.3 mg/dl) in patients with PHPT [RR 20 (95% CI 6.04 - 68.52, I² = 0%, p_{heterogeneity} < 0·00001)]. Serum PTH levels decreased significantly after 2 weeks and up to 28 weeks after treatment with cinacalcet. In the pooled analysis of the 17 cohort studies, serum calcium levels normalized in 76% (95% CI 66% to 86%; I² = 92%, p_{heterogeneity} < 0·00001) of patients regardless of the duration of treatment. In most studies, PTH levels decreased by 13% to 55%. No RCT reported on BMD as a primary or secondary outcome, and no improvement in BMD was noted in the 2 non-randomized studies that reported densitometric findings. No significant difference in urinary calcium was noted with cinacalcet therapy in either the RCTs or non-randomized studies. There was no significant difference in overall adverse events (AE) (RD 0.01, 95% CI -0.07 to 0.26) compared to placebo noted in the RCTs. In the non-randomized studies, pooled weighted AE rate was 45% (95% CI 32 to 59%). Risk of bias was low in 2/4 RCTs and 6/17cohort studies; risk was intermediate in 2/4 RCTs and 8/17 cohort studies, and risk was high in 3/17 cohort studies. In PHPT, cinacalcet lowers serum calcium and PTH with greater effects on calcium than on PTH in the short term. In the doses reported, the drug is safe with tolerable side effects. These findings can help inform targeted medical therapy of PHPT in those for whom lowering the serum calcium is indicated and for whom parathyroidectomy is not an option.

Hashimoto's thyroiditis on outcomes in papillary thyroid cancer revisited: experience from South East Asia

INTRODUCTION

The association between Hashimoto Thyroiditis (HT) and papillary thyroid cancer (PTC) remains uncertain. HT, the most common inflammatory condition of the thyroid, is postulated to increase the risk of PTC and yet confer cancer-retarding effects. In this study, we aim to evaluate the prevalence of HT in patients surgically treated for PTC and evaluate the long-term prognostic implications.

METHODS

This is a retrospective study of 521 patients with PTC who underwent hemi- or total thyroidectomy between January 2000 and December 2018 at a tertiary referral centre. Patients were categorised into two group: group A (n=402) consists of patients with PTC without HT, whereas group B (n=119) consists of patients with PTC and HT. Demographic and clinicopathological details, recurrence rates and overall survival were collected. Univariate and multivariate analyses were performed to evaluate for clinical factors associated with HT.

RESULTS

A total of 521 patients with a mean age of 46.7 years were evaluated. HT was detected in 22.8% of patients with PTC. On multivariate analysis, presence of HT was associated with a lower incidence of extrathyroidal extension (hazard ratio: 0.59, 95%confidence interval 0.37-0.95). Also, patients with HT tend to have fewer cycles of radioactive iodine and correspondingly have excellent response to treatment. However, no differences in recurrence rates and overall survival were detected.

CONCLUSIONS

One-fifth of patients with PTC have coexisting HT. These patients tend to have less-aggressive tumour features such as extrathyroidal extension. However, the effect of HT on recurrence and overall survival appears to be inconsequential clinically.

Do Ultrasound Patterns and Clinical Parameters Inform the Probability of Thyroid Cancer Predicted by Molecular Testing in Nodules with Indeterminate Cytology?

Background: Molecular testing (MT) is commonly used to refine cancer probability in thyroid nodules with indeterminate cytology. Whether or not ultrasound (US) patterns and clinical parameters can further inform the risk of thyroid cancer in nodules predicted to be positive or negative by MT remains unknown. The aim of this study was to test if clinical parameters, including patient age, sex, nodule size (by US), Bethesda category (III, IV, V), US pattern (American Thyroid Association [ATA] vs. American College of Radiology Thyroid Image Reporting and Data System [TI-RADS] systems), radiation exposure, or family history of thyroid cancer can modify the probability of thyroid cancer or noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) predicted by MT. Methods: We studied 257 thyroid nodules in 232 patients from 10 study centers with indeterminate fine needle aspiration cytology and informative MT results using the ThyroSeq v3 genomic classifier (TSv3). Univariate and multivariate logistic regression was used for data analysis. Results: The presence of cancer/NIFTP was associated with positive TSv3 results (odds ratio 61.39, p < 0.0001). On univariate regression, patient sex, age, and Bethesda category were associated with cancer/NIFTP probability (p < 0.05 for each). Although ATA (p = 0.1211) and TI-RADS (p = 0.1359) US categories demonstrated positive trends, neither was significantly associated with cancer/NIFTP probability. A multivariate regression model incorporating the four most informative non-MT covariates (sex, age, Bethesda category, and ATA US pattern; Model No. 1) yielded a C index of 0.653; R² = 0.108. When TSv3 was added to Model number 1, the C index increased to 0.888; R² = 0.572. However, age (p = 0.341), Bethesda category (p = 0.272), and ATA US pattern (p = 0.264) were nonsignificant, and other than TSv3 (p < 0.0001), male sex was the only non-MT parameter that potentially contributed to cancer/NIFTP risk (p = 0.095). The simplest and most efficient clinical model (No. 3) incorporated TSv3 and sex (C index = 0.889; R² = 0.588). Conclusions: In this multicenter study of thyroid nodules with indeterminate cytology and MT, neither the ATA nor TI-RADS US scoring systems further informed the risk of cancer/NIFTP beyond that predicted by TSv3. Although age and Bethesda category were associated with cancer/NIFTP probability on univariate analysis, in sequential nomograms they provided limited incremental value above the high predictive ability of TSv3. Patient sex may contribute to cancer/NIFTP risk in thyroid nodules with indeterminate cytology.

A Multiplex Thyroid-Specific Assay for Quantification of Circulating Thyroid Cell-Free RNA in Plasma of Thyroid Cancer Patients

Background

The standard of care for thyroid cancer management is thyroidectomy and adjuvant radioactive iodine (RAI). There is a paucity of clinical tool that quantifies residual thyroid volume reliably for precise adjuvant RAI dosing. Serum thyroglobulin (TG), tumour marker for thyroid cancer, takes 4 weeks for complete clearance due to its long half-life, and might be undetectable in 12% of structural disease patients. It detects recurrence with a sensitivity of 19-40%, mainly attributed to issue of TG antibody interference with TG immunometric assay. We hypothesise that the quantity of thyroid-specific cell-free RNA (cfRNA) is indicative of amount of thyroid tissues, and that during thyroid surgery, cfRNA levels decrease accordingly.

Methods

We identified 11 biologically significant and highly expressed thyroid-specific targets from Human Protein Atlas and literature. To assess for a fall in thyroid-specific cfRNA level, we recruited 16 patients undergoing thyroid surgery or RAI for malignant or benign thyroid disease, and tracked longitudinal trend of cfRNA. To assess the utility of cfRNA in detecting metastatic thyroid cancer, cfRNA of 11 patients at intermediate to high risk of recurrence was measured during surveillance and at time of clinical recurrence.

Results

The multiplex assay was capable of amplifying and quantifying multiple thyroid-specific genes in a single reaction. The selected targets were amplified successfully from RNA extracted directly from the thyroid (positive control), indicating that they were highly expressed within thyroid tissue. These cfRNAs were present in plasma, in amounts quantifiable using qRT-PCR. Four cfRNA transcripts (TPO, GFRA2, IVD, TG) fell post-treatment in more than 50% of cohort. The thyroid peroxidase (TPO) cfRNA fell post-therapy in 63% of cohort by 80%, as early as 1 day post-treatment, supporting the potential role as early indicator of remnant thyroid tissue volume. We demonstrated the clinical relevance of circulating TPO cfRNA by tracking temporal changes in setting of peri-treatment, recurrence, and TG Ab positive state.

Conclusion

Using a multiplex pre-amplification approach, the TPO cfRNA was a potential biomarker that can track residual thyroid mass. It can be further optimised for quantification of thyroid volume to guide RAI doses and for detection of thyroid cancer recurrence.

Prevalence of thyroid malignancy and hormonal dysfunction following radiation exposure in childhood

INTRODUCTION

Childhood radiation exposure is a known risk factor for thyroid malignancy and dysfunction. However, local data are limited and there is no consensus on the modality and frequency of screening in this high-risk group.

METHODS

Retrospective analysis study evaluating patients with childhood radiation exposure in 2006-2016 and minimum of 1-year follow-up.

RESULTS

Of the 132 childhood cancer survivors in the study, thyroid malignancy was detected in 2 cases (1.5%) and thyroid nodules in 13 (9.8%). The earliest thyroid malignancy was detected 5 years post-radiotherapy via ultrasound. Of the 84 patients who had screening thyroid function test, 26 (31.0%) were detected with abnormal test results post-radiation, majority being subclinical hypothyroidism.

CONCLUSION

Regular screening via clinical examination for thyroid nodules should be performed at least annually. Where feasible and if resources permit, consideration should be given to using ultrasound for thyroid nodule(s) and malignancy screening at 5 years post-radiation therapy. Screening for thyroid dysfunction can be considered from 6-12 months post-radiotherapy.

Frequent neck US in papillary thyroid cancer likely detects non-actionable findings

BACKGROUND

American Thyroid Association (ATA) low-intermediate-risk papillary thyroid cancer (PTC) patients without structural and biochemical evidence of disease on initial post-treatment evaluation have a low risk of recurrence. Studies have shown that with current ultrasound scans (US) and thyroglobulin assays, recurrences mostly occurred 2-8 years after initial therapy. The ATA recommends that neck US be done 6-12 months after surgery to establish patient's response to therapy, then periodically depending on risk of recurrence. The lack of clarity in recommendations on timing of follow-up US and fear of recurrence leads to frequent tests.

OBJECTIVES

To evaluate the utility of routine neck US in ATA low-intermediate-risk PTC patients with no structural disease on neck US and non-stimulated thyroglobulin <1.0 ng/mL after initial therapy.

METHODS

A retrospective study of 93 patients from Singapore, Saudi Arabia and Argentina with ATA low (n = 49) to intermediate (n = 44) risk PTC was conducted between 1998 and 2017. The outcome was to measure the frequency of identifying structural disease recurrence and non-actionable US abnormalities.

RESULTS

Over a median follow-up of 5 years, five of the 93 patients (5.4%) developed structural neck recurrence on US at a median of 2.5 years after initial treatment. Indeterminate US abnormalities were detected in 19 of the 93 patients (20.4%) leading to additional tests, which did not detect significant disease.

CONCLUSION

In ATA low-intermediate-risk PTC with no suspicious findings on neck US and a non-stimulated thyroglobulin of <1.0 ng/mL after initial therapy, frequent US is more likely to identify non-actionable abnormalities than clinically significant disease.

[Art comparison between Zhenghe Bencao (Huiming sanctum edition) and Daguan Bencao(Liu Jia edition)]

Inheriting the medicinal illustrations in Bencao Tujing(, Illustration of Materia Medica), the two picture books of Zhenghe Bencao(, Pharmacopoeia of the Zhenghe reign) Huiming Sanctum edition and Daguan Bencao(, Pharmacopoeia of the Daguan reign) Liu Jia edition show different styles and characteristics in illustrations. They present different art styles and features in medicinal illustrations of ores, plants and animals because of the regional influences from the south and the north. In the process of carving and printing the illustrations of the two classics, different attitudes lead to similarities in the outline and yet differences in details. Besides, the different artistic levels in carving and printing contribute to different artistic standards. Compared with the paintings created in Song Dynasty, more subtle features are lost in Zhenghe Bencao(Huiming Sanctum edition) than in Daguan Bencao (Liu Jia edition). Therefore, the Zhenglei Bencao (, Collected Classified Materia Medica) Huiming Sanctum edition are much closer to the ones in Bencao Tujing and the real medicinals as well than those in Daguan Bencao (Liu Jia edition).

Crash Landing of Thyroid Storm: A Case Report and Review of the Role of Extra-Corporeal Systems

Thyroid storm is a rare but life-threatening endocrinological emergency with significant mortality ranging from 10-30% with multi-organ involvement and failure. In view of the rarity of this condition and efficacy of established first line medical treatment, use of extra-corporeal treatments are uncommon, not well-studied, and its available evidence exists only from case reports and case series. We describe a 28-year-old man who presented with an out-of-hospital cardiac arrest secondary to thyroid storm. Despite conventional first-line pharmacotherapy, he developed cardiogenic shock and circulatory collapse with intravenous esmolol infusion, as well as multi-organ failure. He required therapeutic plasma exchange, concurrent renal replacement therapy, and veno-arterial extra-corporeal membrane oxygenation, one of the few reported cases in the literature. While there was clinical stabilization and improvement in tri-iodothyronine levels on three extra-corporeal systems, he suffered irreversible hypoxic-ischemic brain injury. We reviewed the use of early therapeutic plasma exchange and extra-corporeal membrane oxygenation, as well as the development of other novel extra-corporeal modalities when conventional pharmacotherapy is unsuccessful or contraindicated. This case also highlights the complexities in the management of thyroid storm, calling for caution with beta-blockade use in thyrocardiac disease, with close monitoring and prompt organ support.

Non-Coding RNAs: Uncharted Mediators of Thyroid Cancer Pathogenesis

Thyroid cancer is the most prevalent malignancy of the endocrine system and the ninth most common cancer globally. Despite the advances in the management of thyroid cancer, there are critical issues with the diagnosis and treatment of thyroid cancer that result in the poor overall survival of undifferentiated and metastatic thyroid cancer patients. Recent studies have revealed the role of different non-coding RNAs (ncRNAs), such as microRNAs (miRNAs), long non-coding RNAs (lncRNAs) and circular RNAs (circRNAs) that are dysregulated during thyroid cancer development or the acquisition of resistance to therapeutics, and may play key roles in treatment failure and poor prognosis of the thyroid cancer patients. Here, we systematically review the emerging roles and molecular mechanisms of ncRNAs that regulate thyroid tumorigenesis and drug response. We then propose the potential clinical implications of ncRNAs as novel diagnostic and prognostic biomarkers for thyroid cancer.

Prevalence of thyroid eye disease in Graves' disease: A meta-analysis and systematic review

OBJECTIVE

Thyroid eye disease (TED) is a debilitating condition that frequently manifests in patients suffering from Graves' disease (GD). This study aims to analyse the prevalence of TED among GD patients, with a focus on geographical region-specific rates.

METHODS

Medline and Embase were searched for articles examining TED prevalence on April 2020, and articles were retrieved and sieved. Statistical analysis was performed after Freeman-Tukey double arcsine transformation. Thereafter, results were pooled with random effects by DerSimonian and Laird model.

RESULTS

Fifty-seven articles involving 26,804 patients were included in the review. The overall pooled prevalence of TED was 40% (CI: 0.32 to 0.48) and by continent was 38% (CI: 0.31 to 0.46) for Europe, 44% (CI: 0.32 to 0.56) for Asia, 27% (CI: 0.06 to 0.56) for North America and 58% (CI: 0.55 to 0.61) for Oceania. The prevalence of TED in Southeast Asia was 35% (CI: 0.24 to 0.47) and Middle East 48% (CI: 0.19 to 0.78). Subgroup analysis showed regions with predominantly Caucasians (37%; CI: 0.28 to 0.46) had a lower prevalence of TED compared to Asians (45%; CI: 0.33 to 0.58). The pooled prevalence of lid retraction was 57% (CI: 0.39 to 0.74), proptosis 57% (CI: 0.48 to 0.65), diplopia 36% (CI: 0.24 to 0.48) and ocular hypertension 13% (CI: 0.06 to 0.19).

CONCLUSION

A substantial proportion of patients with GD have TED and often manifest as lid retraction, proptosis and diplopia. Early detection through active screening might help to mitigate the progression of TED and its associated complications.

Cinacalcet and primary hyperparathyroidism: systematic review and meta regression

PURPOSE

Primary hyperparathyroidism (PHPT) is a common condition affecting people of all ages and is mainly treated with parathyroidectomy. Cinacalcet has been widely used in secondary or tertiary hyperparathyroidism, but the use of cinacalcet in PHPT is less clear.

METHODS

Searches were conducted in Medline and Embase for cinacalcet use in PHPT from induction to 10 April 2020. Articles and conferences abstracts describing the use of cinacalcet for PHPT in prospective or retrospective cohorts and randomized controlled trials restricted to English language only. We initially identified 1301 abstracts. Each article went extraction by two blinded authors on a structured proforma. Continuous outcomes were pooled with weight mean difference (WMD). Quality of included articles was assessed with Newcastle Ottwa Scale and Cochrane Risk of Bias 2.0.

RESULTS

Twenty-eight articles were included. Normalization rate of serum Ca levels was reported at 90% (CI: 0.82 to 0.96). Serum levels of Ca and PTH levels were significantly reduced (Ca, WMD: 1.647, CI: -1.922 to -1.371; PTH, WMD: -31.218, CI: -41.671 to -20.765) and phosphate levels significantly increased (WMD: 0.498, CI: 0.400 to 0.596) after cinacalcet therapy. The higher the baseline Ca levels, the greater Ca reduction with cinacalcet treatment. Age and gender did not modify the effect of cinacalcet on serum Ca levels.

CONCLUSION

The results from the meta-analysis support the use of cinacalcet as an alternative or bridging therapy to treat hypercalcemia in people with PHPT.

MON-LB79 Do Ultrasound Patterns and Clinical Parameters Modify the Probability of Thyroid Cancer Predicted by Molecular Testing in Thyroid Nodules With Indeterminate Cytology?

Background: Molecular testing (MT) is commonly used to refine cancer probability in thyroid nodules with indeterminate cytology. Whether or not ultrasound (US) patterns and clinical parameters can further modify the risk of cancer in nodules predicted to be positive or negative by molecular testing remains unknown. Aim: To test if clinical parameters, including age, gender, nodule size (by US), Bethesda category (III, IV, V), US pattern (American Thyroid Association [ATA] system vs American College of Radiology TIRADS), radiation exposure, and family history of thyroid cancer (TC) can modify the probability of TC or NIFTP predicted by MT in thyroid nodules with indeterminate cytology. Methods: We studied 257 thyroid nodules from 10 study centers with fine-needle aspiration (FNA) yielding indeterminate cytology and informative MT results using the ThyroSeq v3 genomic classifier (TSv3). Univariate and multivariate logistic regression were used for data analysis. Results: In this group of thyroid nodules, out of all parameters studied using univariate regression, patient gender, age, and Bethesda category were significantly associated with TC/NIFTP probability (P<0.05 for each). The ATA US patterns showed a positive trend (P=0.1211), whereas TIRADS was not predictive (P=0.3135). A multivariate regression model incorporating the four most informative covariates (gender, age, Bethesda category, and ATA US patterns) (model #1) yielded a C index=0.653; R²=0.108. Male gender and Bethesda category V significantly increased risk, and age demonstrated a nonlinear risk profile. When TSv3 was added to model #1, the C index increased to 0.888; R²=0.572. However, age (P=0.341), Bethesda category (P=0.272), and the ATA US patterns (P=0.264) had limited predictive ability in comparison with TSv3, which dominated the predictive performance (P<0.001). Gender was the only parameter showing tendency for significance beyond MT (P=0.095). The most parsimonious model incorporated gender and TSv3 (C index=0.889; R²=0.588). Conclusions: While often useful in selecting thyroid nodules for FNA, neither the ATA US nor the TIRADS scoring systems were informative in further predicting TC/NIFTP in thyroid nodules with indeterminate FNA cytology. Although age and Bethesda category were associated with TC/NIFTP probability on univariate analysis, they had limited incremental value above the high predictive ability of TSv3. Gender was the only parameter with potential contribution to predicting TC/NIFTP in addition to MT.

Performance of a Multigene Genomic Classifier in Thyroid Nodules With Indeterminate Cytology: A Prospective Blinded Multicenter Study

Question

Can the diagnosis of benign disease or cancer in thyroid nodules with indeterminate cytology be established by molecular testing instead of diagnostic surgery?

Findings

This prospective, blinded, multicenter cohort study of a multigene genomic classifier (ThyroSeq v3) test included 257 indeterminate cytology thyroid nodules with informative test results. It demonstrated a high sensitivity (94%) and reasonably high specificity (82%), with 61% of the nodules yielding a negative test result and only 3% residual cancer risk in these nodules.

Meanings

Up to 61% of patients with indeterminate cytology thyroid nodules may avoid diagnostic surgery by undergoing multigene genomic classifier testing.

Importance

Approximately 20% of fine-needle aspirations (FNA) of thyroid nodules have indeterminate cytology, most frequently Bethesda category III or IV. Diagnostic surgeries can be avoided for these patients if the nodules are reliably diagnosed as benign without surgery.

Objective

To determine the diagnostic accuracy of a multigene classifier (GC) test (ThyroSeq v3) for cytologically indeterminate thyroid nodules.

Design, Setting, and Participants

Prospective, blinded cohort study conducted at 10 medical centers, with 782 patients with 1013 nodules enrolled. Eligibility criteria were met in 256 patients with 286 nodules; central pathology review was performed on 274 nodules.

Interventions

A total of 286 FNA samples from thyroid nodules underwent molecular analysis using the multigene GC (ThyroSeq v3).

Main Outcomes and Measures

The primary outcome was diagnostic accuracy of the test for thyroid nodules with Bethesda III and IV cytology. The secondary outcome was prediction of cancer by specific genetic alterations in Bethesda III to V nodules.

Results

Of the 286 cytologically indeterminate nodules, 206 (72%) were benign, 69 (24%) malignant, and 11 (4%) noninvasive follicular thyroid neoplasms with papillary-like nuclei (NIFTP). A total of 257 (90%) nodules (154 Bethesda III, 93 Bethesda IV, and 10 Bethesda V) had informative GC analysis, with 61% classified as negative and 39% as positive. In Bethesda III and IV nodules combined, the test demonstrated a 94% (95% CI, 86%-98%) sensitivity and 82% (95% CI, 75%-87%) specificity. With a cancer/NIFTP prevalence of 28%, the negative predictive value (NPV) was 97% (95% CI, 93%-99%) and the positive predictive value (PPV) was 66% (95% CI, 56%-75%). The observed 3% false-negative rate was similar to that of benign cytology, and the missed cancers were all low-risk tumors. Among nodules testing positive, specific groups of genetic alterations had cancer probabilities varying from 59% to 100%.

Conclusions and Relevance

In this prospective, blinded, multicenter study, the multigene GC test demonstrated a high sensitivity/NPV and reasonably high specificity/PPV, which may obviate diagnostic surgery in up to 61% of patients with Bethesda III to IV indeterminate nodules, and up to 82% of all benign nodules with indeterminate cytology. Information on specific genetic alterations obtained from FNA may help inform individualized treatment of patients with a positive test result.

BRAF mutation in papillary thyroid cancer-Prevalence and clinical correlation in a South-East Asian cohort

OBJECTIVE

BRAF mutation is the commonest mutation seen in papillary thyroid cancer (PTC), but its prevalence and clinical significance vary across countries. We aim to evaluate the prevalence and clinico-pathological correlation of BRAF mutation in PTC patients at our centre.

STUDY DESIGN

Retrospective cohort study of 75 consecutive archival thyroid specimens, whereby BRAF mutation was detected using a polymerase chain reaction (PCR) technique and correlated with clinical and pathological features and outcomes.

SETTING

Tertiary university hospital in Singapore.

PARTICIPANTS

A total of 75 consecutive histologically proven archival thyroid specimens from patients who underwent thyroidectomy for PTC were accrued for this study.

MAIN OUTCOME MEASURES

Main outcome is to determine the prevalence of the BRAF mutation in our South-East Asian population. Secondary aim is to correlate the mutational status with adverse pathological features like histological variants, multi-focality, lymphovascular invasion and extra-thyroidal extension, clinical features like demographics, TNM stage, recurrence and survival, as well as treatment details like type of surgery performed and radioiodine doses.

RESULTS

BRAF mutation was detected in 56% (42/75) of PTC. All but one BRAF-mutated PTC had the BRAFV600E mutation. BRAF-mutated tumours were associated with an advanced T-stage (P = 0.049) and were more likely to have a central neck dissection (P = 0.036). There was no significant correlation between BRAF mutation status and clinical outcomes.

CONCLUSION

The prevalence of BRAF mutation is 56%. BRAF mutation-positive tumours were associated with locally advanced disease, but not poorer survival.

[The Wuhan Twin Birth Cohort Study]

The prevalence of child and adolescent growth and mental-behavior related diseases are increasing, and the pathogenesis are complex. Twins are excellent natural resources for complex chronic diseases research as they share the maternal intrauterine environment, born at the same time and share the same family environment in early years, which could benefit the adjust ment of confounding factors, such as age, genetic factors and early family environmental factors. Birth cohort with twin families involved could be more effective in exploring the genetic and environmental factors for complex chronic diseases at the very beginning of life. This paper summarizes the objective, content, progress, strengths and potential problems of Wuhan Twin Birth Cohort, with emphasis on the overall design and progress of the study.

Retrospective Review of Atypical Femoral Fracture in Metastatic Bone Disease Patients Receiving Denosumab Therapy

BACKGROUND

Denosumab therapy is used to reduce skeletal-related events in metastatic bone disease (MBD). There have been reports of atypical femoral fracture (AFF) in osteoporotic patients treated with denosumab but none in the context of higher dose and more frequent denosumab therapy for MBD. The goal of this study was to assess the incidence of AFF in MBD.

PATIENTS AND METHODS

We conducted a retrospective review of 253 patients who received a minimum of 12 doses of denosumab at 120 mg each for MBD. To identify patients with asymptomatic atypical stress reactions in the lateral subtrochanteric femur (which precede fractures), we reviewed the skeletal images of 66 patients who had received at least 21 doses of denosumab for AFF features.

RESULTS

These patients received a median of 17 doses, with a median treatment duration of 23 months. There was 1 case of undiagnosed clinical AFF detected after chart review and 2 cases of subclinical atypical femoral stress reaction observed on imaging review after 23 doses of denosumab over 33 months, 28 doses over 27 months, and 21 doses over 21 months, respectively. Scout computed tomography films showed diffuse cortical thickening of diaphysis with localized periosteal reaction of lateral femoral cortex. Bone scan and magnetic resonance imaging scan of 2 patients with stress reactions confirmed the diagnosis.

CONCLUSION

The incidence of clinical AFF in this context is 0.4% (1/253; 95% confidence interval [CI] 0.1%-2.2%), and the incidence of atypical femoral stress reaction based on imaging review is 4.5% (3/66; 95% CI 1.6%-12.5%). Clinicians should be aware of the clinical prodrome (which may or may not be present) and antecedent imaging changes associated with AFF. The Oncologist 2017;22:438-444Implications for Practice: Among patients with metastatic bone disease treated with denosumab, cases of clinical and subclinical atypical femoral fracture (AFF) are rare. The one detected case of clinical fracture went unrecognized despite prodromic symptoms. Clinicians should be aware of (a) the potential prodrome of anterior thigh/groin pain and (b) subclinical imaging changes in the lateral femur, both of which may precede clinical AFF.

Familial non-medullary thyroid cancer: unraveling the genetic maze

Familial non-medullary thyroid cancer (FNMTC) constitutes 3-9% of all thyroid cancers. Out of all FNMTC cases, only 5% in the syndromic form has well-studied driver germline mutations. These associated syndromes include Cowden syndrome, familial adenomatous polyposis, Gardner syndrome, Carney complex type 1, Werner syndrome and DICER1 syndrome. It is important for the clinician to recognize these phenotypes so that genetic counseling and testing can be initiated to enable surveillance for associated malignancies and genetic testing of family members. The susceptibility chromosomal loci and genes of 95% of FNMTC cases remain to be characterized. To date, 4 susceptibility genes have been identified (SRGAP1 gene (12q14), TITF-1/NKX2.1 gene (14q13), FOXE1 gene (9q22.33) and HABP2 gene (10q25.3)), out of which only the FOXE1 and the HABP2 genes have been validated by separate study groups. The causal genes located at the other 7 FNMTC-associated chromosomal loci (TCO (19q13.2), fPTC/ PRN (1q21), FTEN (8p23.1-p22), NMTC1 (2q21), MNG1 (14q32), 6q22, 8q24) have yet to be identified. Increasingly, gene regulatory mechanisms (miRNA and enhancer elements) are recognized to affect gene expression and FNMTC tumorigenesis. With newer sequencing technique, along with functional studies, there has been progress in the understanding of the genetic basis of FNMTC. In our review, we summarize the FNMTC studies to date and provide an update on the recently reported susceptibility genes including novel germline SEC23B variant in Cowden syndrome, SRGAP1 gene, FOXE1 gene and HABP2 genes in non-syndromic FNMTC.

SERIAL NECK ULTRASOUND IS MORE LIKELY TO IDENTIFY FALSE-POSITIVE ABNORMALITIES THAN CLINICALLY SIGNIFICANT DISEASE IN LOW-RISK PAPILLARY THYROID CANCER PATIENTS

OBJECTIVE

American Thyroid Association (ATA) low-risk papillary thyroid cancer (PTC) patients without structural evidence of disease on initial posttreatment evaluation have a low risk of recurrence. Despite this, most patients undergo frequent surveillance neck ultrasound (US). The objective of the study was to evaluate the clinical utility of routine neck US in ATA low-risk PTC patients with no structural evidence of disease after their initial thyroid surgery.

METHODS

We performed a retrospective review of 171 ATA low-risk PTC patients after total thyroidectomy, with or without radioactive iodine (RAI) ablation, who had a neck US without suspicious findings after therapy. The main outcome measure was a comparison of the frequency of finding false-positive US abnormalities and the frequency of identifying structural disease recurrence.

RESULTS

Over a median follow-up of 8 years, 171 patients underwent a median of 5 neck US (range 2-17). Structural recurrence with low-volume disease (≤1 cm) was identified in 1.2% (2/171) of patients at a median of 2.8 years (range 1.6-4.1 years) after their initial diagnosis. Recurrence was associated with rising serum thyroglobulin (Tg) level in 1 of the 2 patients and was detected without signs of biochemical recurrence in the other patient. Conversely, false-positive US abnormalities were identified in 67% (114/171) of patients after therapy, leading to additional testing without identifying clinically significant disease.

CONCLUSION

In ATA low-risk patients without structural evidence of disease on initial surveillance evaluation, routine screening US is substantially more likely to identify false-positive results than clinically significant structural disease recurrence.

PRACTICAL BARRIERS TO IMPLEMENTATION OF THYROID CANCER GUIDELINES IN THE ASIA-PACIFIC REGION

OBJECTIVE

Numerous published guidelines have described the optimal management of thyroid cancer. However, these rely on the clinical availability of diagnostic and therapeutic modalities. We hypothesized that the availability of medical resources and economic circumstances vary in Asia-Pacific countries, making it difficult to implement guideline recommendations into clinical practice.

METHODS

We surveyed participants at the 2009 and 2013 Congresses of the Association of Southeast Asian Nations Federation of Endocrine Societies by distributing questionnaires to attendees at registration.

RESULTS

Responses were obtained from 268 respondents in 2009 and 163 respondents in 2013. Similar to the high prevalence of low-risk thyroid cancer observed in the Surveillance, Epidemiology, and End Results database, across the Asia-Pacific countries surveyed in 2009 and 2013, 50 to 100% of the respondents from the Philippines, Malaysia, Singapore, China, Taiwan, Thailand, Hong Kong, Korea, and Sri Lanka reported that more than 50% of the patients had low-risk thyroid cancer on follow-up. Importantly, there was much variation with regards to the perceived availability of investigation and treatment modalities.

CONCLUSION

We found a wide variation in clinicians' perception of availability of diagnostic and therapeutic modalities in the face of a rise in thyroid cancer incidence and thyroid cancer management guidelines that emphasized their importance. The lack of availability of management tools and treatments will prove to be a major barrier to the implementation of thyroid cancer management guidelines in Southeast Asia, and likely in other parts of the world as well.

Frequent screening with serial neck ultrasound is more likely to identify false-positive abnormalities than clinically significant disease in the surveillance of intermediate risk papillary thyroid cancer patients without suspicious findings on follow-up ultrasound evaluation

CONTEXT

American Thyroid Association (ATA) intermediate-risk thyroid cancer patients who achieve an excellent treatment response demonstrate a low risk of structural disease recurrence. Despite this fact, most patients undergo frequent surveillance neck ultrasound (US) during follow-up.

OBJECTIVE

The objective of the study was to evaluate the clinical utility of routine screening neck US in ATA intermediate-risk patients documented to have a nonstimulated thyroglobulin less than 1.0 ng/mL and a neck US without suspicious findings after therapy.

PATIENTS AND DESIGN

Retrospective review of 90 ATA intermediate-risk papillary thyroid carcinoma patients treated with total thyroidectomy and radioactive iodine ablation in a tertiary referral center.

MAIN OUTCOME MEASURES

A comparison between the frequency of finding false-positive US abnormalities and the frequency of identifying structural disease recurrence in the study cohort was measured.

RESULTS

Over a median of 10 years, 90 patients had a median of six US (range 2-16). Structural disease recurrence was identified in 10% (9 of 90) at a median of 6.3 years. Recurrence was associated with other clinical indicators of disease in 5 of the 90 patients (5.6%, 5 of 90) and was detected without other signs of recurrence in four patients (4.8%, 4 of 84). False-positive US abnormalities were identified in 57% (51 of 90), leading to additional testing, which failed to identify clinically significant disease.

CONCLUSIONS

In ATA intermediate-risk patients who have a nonstimulated thyroglobulin less than 1.0 ng/mL and a neck US without suspicious findings after therapy, frequent US screening during follow-up is more likely to identify false-positive abnormalities than clinically significant structural disease recurrence.

Managing terrorism or accidental nuclear errors, preparing for iodine-131 emergencies: a comprehensive review

Chernobyl demonstrated that iodine-131 (131I) released in a nuclear accident can cause malignant thyroid nodules to develop in children within a 300 mile radius of the incident. Timely potassium iodide (KI) administration can prevent the development of thyroid cancer and the American Thyroid Association (ATA) and a number of United States governmental agencies recommend KI prophylaxis. Current pre-distribution of KI by the United States government and other governments with nuclear reactors is probably ineffective. Thus we undertook a thorough scientific review, regarding emergency response to 131I exposures. We propose: (1) pre-distribution of KI to at risk populations; (2) prompt administration, within 2 hours of the incident; (3) utilization of a lowest effective KI dose; (4) distribution extension to at least 300 miles from the epicenter of a potential nuclear incident; (5) education of the public about dietary iodide sources; (6) continued post-hoc analysis of the long-term impact of nuclear accidents; and (7) support for global iodine sufficiency programs. Approximately two billion people are at risk for iodine deficiency disorder (IDD), the world's leading cause of preventable brain damage. Iodide deficient individuals are at greater risk of developing thyroid cancer after 131I exposure. There are virtually no studies of KI prophylaxis in infants, children and adolescents, our target population. Because of their sensitivity to these side effects, we have suggested that we should extrapolate from the lowest effective adult dose, 15-30 mg or 1-2 mg per 10 pounds for children. We encourage global health agencies (private and governmental) to consider these critical recommendations.

Expression pattern of heat-shock cognate 70 gene of humphead snapper, Lutjanus sanguineus (Cuvier), infected by Vibrio harveyi

The heat-shock cognate 70 (HSC70) gene of humphead snapper, Lutjanus sanguineus, designated as ByHSC70, was cloned by rapid amplification of cDNA ends (RACE) with the primers designed from the known expressed sequence tag (EST) identified from the subtracted cDNA library of the head kidney of humphead snapper. The full-length cDNA of ByHSC70 is 2313 bp, containing a 5' terminal untranslated region (UTR) of 96 bp, a 3' terminal UTR of 267 bp, and an open reading frame (ORF) of 1950 bp encoding a polypeptide of 650 amino acids with a theoretical molecular weight of 71.21 kDa and an estimated isoelectric point (pI) of 5.08. ByHSC70 contained three classical HSP70 family signatures. BLAST analysis showed that the amino acid sequence of ByHSC70 had the highest similarity of 99% when compared with other HSC70s. Fluorescent real-time quantitative RT-PCR was used to examine the expression of ByHSC70 gene in eight kinds of tissues/organs of humphead snapper after challenge with Vibrio harveyi. There was a clear time-dependent expression pattern of ByHSC70 in head kidney, spleen and thymus after bacterial challenge, and the expression of mRNA reached a maximum level at 9, 6 and 24 h post-infection and then returned to control levels after 15, 24 and 36 h, respectively. Our results suggest that HSC70 is an important component in the immune system of humphead snapper, its their rapid transcriptional upregulation in response to V. harveyi infection might be important for survival of humphead snapper.

Effects of nano-surface properties on initial osteoblast adhesion and Ca/P adsorption ability for titanium alloys

Titanium alloys (Ti6Al4V), while subjected to high temperature surface treatment, experience altered nano-surface characteristics. The effects of such surface treatments are examined, including the initial adhesion force experienced by osteoblasts, the Ca/P adsorption capability, and the nano-surface properties, including the amounts of amphoteric Ti-OH groups, surface topography, and surface roughness. The initial adhesion force is considered a quantitative indicator of cyto-compatibility in vitro. Previously, a cyto-detacher was applied in a pioneer attempt measuring the initial adhesion force of fibroblasts on a metal surface. Presently, the cyto-detacher is further applied to evaluate the initial adhesion force of osteoblasts. Results reveal that (1) titanium alloys subjected to heat treatment could promote the adsorption capability of Ca and P; (2) titanium alloys subjected to heat treatment could have higher initial osteoblast adhesion forces; (3) the adhesion strength of osteoblasts, ranging from 38.5 to 58.9 nN (nanonewtons), appears stronger for rougher surfaces. It is concluded that the heat treatment could have impacted the biocompatibility in terms of the initial osteoblast adhesion force and Ca/P adsorption capability.

Abnormal 201Tl myocardial single photon emission computed tomography in energetic male patients with myocardial bridge

Myocardial bridge is a relatively benign condition where a major coronary artery is bridged by a band of muscle and narrows during systole, particularly during rapid heart rates. Its clinical presentation and electrocardiogram (ECG) changes overlap with that of coronary artery disease. 201Tl myocardial perfusion imaging is thus frequently prescribed for further evaluation. This retrospective study was carried out to determine the 201Tl image patterns in patients with myocardial bridge. A total of 17 male patients (aged from 30 to 63 years) who had a positive exercise ECG and angiographic evidence of myocardial bridge in the mid-third of the left anterior descending coronary artery were recruited. Most of them were robust and received routine physical check-ups. They had no known heart disease or medication that affected cardiac function. The patients' clinical presentations, echocardiograph and exercise ECG findings were analysed. 201Tl single photon emission computed tomography (SPECT) was performed by intravenous injection of 201Tl (111 MBq) immediately following stress (treadmill or dipyridamole induced) and 4 h after stress, using a fixed, right angle camera equipped with a low energy, general purpose collimator. The images were interpreted independently by two experienced nuclear medicine physicians. Nine of the 17 patients had anterior chest pain during exercise. All patients had an abnormal ECG during exercise, including ST-T wave depression in leads II, III and aVF, and v4-6. Except for eight patients revealing reversible perfusion defect (R), 16 of the 17 patients also exhibited a partial reversible perfusion defect (PR) or a significant reverse redistribution (RR) scan pattern in the anterior or inferior walls of the left ventricle. Myocardial bridge should be taken into consideration in energetic male patients who had abnormal exercise ECGs and the corresponding patterns of Tl SPECT abnormalities including R, PR and RR.

Clinical characteristics of Group G streptococcal bacteremia in Taiwan

The results of this retrospective study showed that Group G streptococcal bacteremia was an acute febrile disease with low mortality. Most patients were > 60 y old but there was a strong association between age < 60 y and malignancy. Cases clustered in summer and the most common port of entry was the skin.

Two novel cytotoxic and antimicrobial triterpenoids from Pseudolarix kaempferi

Two novel antimicrobial and cytotoxic triterpenoids, isopseudolarifuroic acids A (1) and B (2), were isolated from the bark of Pseudolarix kaempferi. The structural elucidation of two novel compounds was carried out mainly by spectroscopic methods, and also by computer modeling. Compounds 1 and 2 exhibited significant cytotoxic activities against several tumor cell lines. Compound 1 also showed most potent antimicrobial activities against both Gram-positive and Gram-negative bacteria.

Prenatal ultrasound findings in a fetus with paternal uniparental disomy 14q12-qter

We present the prenatal ultrasound findings in a case of postnatally identified paternal uniparental isodisomy 14q12-qter. Increased nuchal translucency and a large omphalocele were identified at 14 weeks' gestation. Karyotyping revealed a normal male, 46,XY. As gestation advanced, polyhydramnios developed, skeletal abnormalities involving the long bones and chest became evident, hand contractures developed, and the presumed large omphalocele was in part found to be a large ventral hernia, as echogenic adipose tissue could be seen in the abdominal wall near to the cord insertion. Prenatal findings were confirmed after delivery and central nervous system imaging revealed lissencephaly. The combination of an abdominal wall defect with either increased nuchal translucency or skeletal abnormalities should prompt an investigation for uniparental disomy 14 even if the karyotype is normal.

Salvia miltiorrhiza inhibits intimal hyperplasia and monocyte chemotactic protein-1 expression after balloon injury in cholesterol-fed rabbits

Antioxidants that prevent low density lipoproteins (LDL) from oxidation may inhibit atherosclerosis and post-angioplasty restenosis. Salvia miltiorrhiza (SM) has been shown to inhibit LDL oxidation and reduce atherosclerosis in cholesterol-fed rabbits. The effects of SM on neointimal hyperplasia and monocyte chemotactic protein-1 (MCP-1) expression after balloon injury were studied. Male New Zealand white rabbits were fed a 2% cholesterol diet together with daily SM (4.8 gm/kg body wt.) treatment (SM; n=10) or without SM as a control (C; n=9) for 6 weeks. Probucol-treated (0.6 gm/kg body wt.) rabbits (P; n=9) were used as a positive control group. A balloon injury of the abdominal aorta was performed at the end of the third week. Aortas were harvested at the end of 6 weeks. The plasma cholesterol levels were lowered in SM group. The neointimal hyperplasia in abdominal aortas was significantly inhibited in SM group [neointima/media area ratio: 0.63+/-0.05 (SM) versus 0.78+/-0.05 (C); P < 0.05] and in P group [0.45+/-0.02 (P) versus 0.78+/-0.05 (C); P < 0.05] when compared with C group. SM treatment significantly reduced MCP-1 mRNA and protein expression in balloon-injured abdominal aorta. These inhibitory effects on intimal response after balloon injury might be attributed to antioxidant capacity and cholesterol lowering effect of SM. SM treatment may offer some protection against post-angioplasty restenosis.

Confined placental mosaicism for trisomy 14 and maternal uniparental disomy in association with elevated second trimester maternal serum human chorionic gonadotrophin and third trimester fetal growth restriction

A case of confined placental mosaicism (CPM) and maternal uniparental isodisomy 14 identified after placental karyotype revealed trisomy 14 in a newborn with intrauterine growth restriction (IUGR) and minor dysmorphic features is reported. During the second trimester of the pregnancy, multiple marker screening revealed an increased risk for Down syndrome of > 1 in 10. The maternal serum human chorionic gonadotrophin (MShCG) was markedly elevated at 4.19 MoM. Amniocentesis revealed a normal 46,XX karyotype. Fetal growth restriction has been associated with elevated MShCG and placental aneuploidy with CPM for chromosomes 2, 7, 9 and 16. The present case of CPM for chromosome 14 was also associated with fetal growth restriction and elevated second trimester MShCG, suggesting a common link. Further studies need to be done to determine if indeed elevation of second trimester MShCG is associated with increased risk of CPM. The present case again demonstrates the need to perform placental karyotype in unexplained fetal growth restriction.

Deregulation of renal transforming growth factor-beta1 after experimental short-term ureteric obstruction in fetal sheep

Renal malformations are the commonest cause of chronic renal failure in children and they are often associated with urinary tract abnormalities that impair fetal urine flow. Up-regulation of transforming growth factor-beta1 (TGF-beta1) occurs after experimental postnatal urinary tract obstruction and we recently reported increased levels of TGF-beta1 in human renal malformations (Yang SP et al, Am J Pathol 2000, 157:1633-1647). These findings led us to propose that obstruction-induced stretch of developing renal epithelia causes up-regulation of TGF-beta1, which then perturbs renal development. In this study, therefore, we examined expression of components of the TGF-beta1 signaling axis in a previously characterized ovine model of fetal short-term urine flow impairment in which complete unilateral ureteric obstruction was induced at 90 days when a few layers of glomeruli had formed. Up-regulation of TGF-beta1 mRNA and protein was observed in obstructed kidneys, compared to sham-operated control organs, after only 10 days. Increased levels of TGF-beta1 receptors I (TGF-betaR1) and II (TGF-betaR2) were also detected on Western blot, and the cytokine and TGF-betaR1 co-localized in disrupted epithelia on immunohistochemistry. De novo expression of alpha-smooth muscle actin, a structural protein up-regulated during TGF-beta1-induced phenotypic switching between human renal dysplastic epithelial and mesenchymal lineages in vitro, was also observed in these aberrant epithelia. These findings implicate increased TGF-beta1 signaling in the early biological changes generated by fetal urinary tract obstruction.

Mating-activated brainstem catecholaminergic neurons in the female rat

Central catecholaminergic systems play an important role in the control of reproductive activities including sexual behavior, luteinizing hormone (LH) and prolactin secretion. It has been reported that catecholaminergic neurons in the locus coeruleus (A6) are activated by mating in rabbits and ferrets, animals known as reflex ovulators. This study used Fos as a marker of neuronal activity to examine whether brainstem catecholaminergic neurons are activated by mating in the spontaneous ovulator, the female rat. Proestrous rats receiving intromissions (mated group) from males or mounts-without-intromission (mounted group) were sacrificed along with rats taken directly from their home cage (control group) 90 min after the beginning of mating or mounting. Double-label immunocytochemistry was used to examine the expression of c-Fos in catecholaminergic neurons labeled by tyrosine hydroxylase (TH) antibody, or adrenergic neurons labeled by phenylethanolamine-N-methyl transferase (PNMT) antibody. Double label immunofluorescent immunohistochemistry was used to determine the number of neurons containing the estrogen receptor (ERalpha) that were activated by mating in these brain areas. The results showed that mating-with-intromissions induced a significant increase in the percentage of TH/Fos colabeled neurons in both A1 and A2 cells compared to mounting-without-intromission or control. In both these areas, over 50% ERalpha-ir neurons were activated after mating while mounting-without-intromission did not affect the percentage of colabeled Fos/ERalpha neurons. In A6 region, neither the expression of Fos nor the percentage of TH/Fos colabeled cells was influenced by either mating or mounting compared to controls. The percentage of PNMT-containing neurons colabeled with Fos was not different in C1 and C2 among the three experimental groups. The results indicate that catecholaminergic neurons were activated by mating in A1 and A2 but not in adjoining adrenergic C1 and C2 cells. In contrast to the findings that catecholaminergic neurons in A6 are activated by mating in induced ovulators, mating did not affect neuronal activity in A6 neurons in the female rat. In A1 and A2 areas, a high percentage of neurons containing ERalpha were activated by mating suggesting both tactile and hormonal information may converge on these populations of neurons. The activated catecholaminergic neurons in A1 and A2 may be an important pathway by which sensory information generated during sexual interaction modulates both behavior and pituitary function.

Initial sequencing and analysis of the human genome

The human genome holds an extraordinary trove of information about human development, physiology, medicine and evolution. Here we report the results of an international collaboration to produce and make freely available a draft sequence of the human genome. We also present an initial analysis of the data, describing some of the insights that can be gleaned from the sequence.

Role of endogenous opioid peptides in protection of ischemic preconditioning in rat small intestine

This study investigated the protective effects of ischemic preconditioning on intestinal ischemic injury and the role of endogenous opioid peptides (EOP) in these effects. Ischemia-reperfusion (I/R) induced by 30-min of ischemia and 60-min of reperfusion significantly increased the levels of malondialdehyde (MDA) and lactate dehydrogenase (LDH) and resulted in serious intestinal edema (wet weight/dry weight). The ischemic preconditioning (PC) elicited by three 8-min occlusion periods interspersed with 10-min reperfusion markedly attenuated intestinal injury caused by ischemia-reperfusion. Pretreatment with morphine (300 microg x kg(-1), i.v.) 10-min before ischemia and reperfusion mimicked the protection produced by PC. Naloxone (3 mg x kg(-1), i.v.) abolished the protection of morphine-induced preconditioning and ischemic preconditioning in rat intestine. However, there were no changes between naloxone alone and control groups. Treatment with naloxone before ischemia-reperfusion had no effect on animals compared with the I/R group. In addition, we also measured the content of endogenous opioid peptides (Leu-enkephalin) in the effluent which was collected before and during preconditioning. It was shown that the release of leu-enkephalin was markedly increased during preconditioning. These results suggested that EOP might play an important role in PC in rat small intestine.

A salvianolic acid B-rich fraction of Salvia miltiorrhiza induces neointimal cell apoptosis in rabbit angioplasty model

Apoptosis has been suggested to participate in stabilizing cell number in restenosis. Salvia miltiorrhiza (SM) Bunge which is a Chinese herb widely used for the treatment of cardiovascular disorders contains a potent antioxidant, Salvianolic acid B. To determine whether the antioxidant affects vascular apoptosis, the present study examined the frequency of apoptotic cell death in atherosclerotic plaques and in restenotic lesions of cholesterol-fed rabbits. New Zealand White rabbits were treated with a normal diet (normal), a 2% cholesterol diet (HC), a 2% cholesterol diet and endothelial denudation (HC-ED), a 2% cholesterol diet with 5% water-soluble extract of SM (4.8 g/Kg B.W./day) and endothelial denudation (HC-ED-SM), or with a 2% cholesterol diet containing probucol (0.6 g/kg B.W./day) and endothelial denudation (HC-ED-probucol). Apoptosis and associated cell types were examined in serial paraffin sections by in situ terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling and immunohistochemistry. The expression of p53, an apoptosis-related protein, was also examined. Apoptosis was mainly detected in the neointima of the three groups with endothelial denudation. The percentage of apoptotic cells in SM-treated group (68.5+/-5.9%) was significantly higher than that of normal (0%), HC (1.9+/-1.2%), HC-ED (46.1+/-5.4%), and probucol-treated (32.8+/-3.9%) groups. The SM treatment markedly reduced the thickness of the neointima which was mainly composed of smooth muscle cells with few macrophages. In accordance with the apoptotic cell counts, positive immunoreactivity for p53 was observed in restenotic lesions from HC-ED, SM-treated and probucol-treated groups but not in the intima of the other two groups. These results suggest that the treatment with salvianolic acid B-rich fraction of SM induces apoptosis in neointima which in turn may help prevent the neointimal thickening.

Iliofemoral vein thrombosis and pulmonary embolism associated with a transient ischemic attack in a patient with antiphospholipid syndrome

Several clinical conditions, such as deep vein thrombosis, cerebral infarct, pulmonary infarct, skin ulcers, renal failure, and habitual abortion, are thought to be associated with the antiphospholipid syndrome. The authors describe a 32-year-old woman who had characteristics of the antiphospholipid syndrome including increased immunoglobulin G-cardiolipin antibody titers, iliofemoral vein thrombosis, pulmonary embolism, headache, visual disturbances, and habitual abortion. During hospitalization, she suddenly experienced right-sided weakness. A Tc-99m HMPAO brain scan showed the probability of a transient ischemic attack in the left frontotemporal cortex.

Using buffy coat for reverse transcriptase-polymerase chain reaction in the diagnosis of dengue virus infection: preliminary study

Using reverse transcriptase-polymerase chain reaction (RT-PCR) to detect and type from viremic human serum samples for dengue virus infection is widely used today. However, a few false-negative results were reported due to very low titers of the virus particle in serum samples. As mononuclear cells, macrophages or monocytes are target cells for dengue virus infection, and the replication of virions can be observed in peripheral leukocytes frequently, the amount of virus particle in buffy coat should be higher than those in serum samples. Here, we describe a procedure in which RNA extraction from the buffy coat of a patient with a false-negative serum sample yielded specific viral RNA amplifiable by RT-PCR, thereby providing an alternative choice for the accurate diagnosis of dengue infection.

Krypton-81m ventilation and technetium-99m macroaggregated albumin perfusion scintigraphy for detection of pulmonary embolism: the first experience in Taiwan

BACKGROUND

This study was designed to assess whether the self-made (Institute of Nuclear Energy Research, Taiwan) krypton (Kr)-81m could be used as a ventilation agent to detect patients with suspected pulmonary embolism (PE). In addition, xenon (Xe)-133 ventilation scintigraphy was also performed for comparison.

METHODS

Forty patients with suspected PE were studied. Each patient received Kr-81m ventilation, Xe-133 ventilation and technetium (Tc)-99m macroaggregated albumin (MAA) perfusion studies on the same day. Images were judged using the criteria of the modified Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED). For those with a high or intermediate probability of PE on lung scans and normal pulmonary function tests, anticoagulants were given and patients were monitored with Tc-99m MAA perfusion studies after treatment. The final diagnosis was based on chest radiography, pulmonary function tests and lung scans.

RESULTS

All 40 patients successfully underwent lung scans. Of these, 11 had PE. Ten of the 11 cases were detected using Kr-81m ventilation and Tc-99m MAA perfusion studies, resulting in a sensitivity of 91%. Seven of 11 cases were detected using Xe-133 ventilation and Tc-99m MAA perfusion studies, resulting in a sensitivity of 64%. Of the 11 patients with PE, four had PE alone; Kr-81m and Xe-133 results agreed in three patients, but Kr-81m detected PE in the remaining patient. Of the remaining seven patients who suffered from PE with obstructive airway disease, Kr-81m and Xe-133 agreed in four, but Kr-81m detected PE in another two patients and one case was missed by both studies.

CONCLUSIONS

Self-made Kr-81m was safe and effective for ventilation scintigraphy in humans. When Kr-81m was used for the detection of PE, it was particularly advantageous when PE occurred in small areas of the lungs or when the patient with PE had concurrent obstructive airway disease.

Hypoxia up-regulates angiopoietin-2, a Tie-2 ligand, in mouse mesangial cells

BACKGROUND

Angiopoietins are secreted factors modulating endothelial survival and morphogenesis. Our previous studies demonstrated angiopoietin-2 (Ang-2) promoter activity in vivo in maturing kidney vascular smooth muscle and mesangial cells, with Tie-2 expressed by adjacent endothelia, including glomerular capillaries.

METHODS

In this study we investigated Ang-2 expression in immortalized mouse mesangial cell lines and studied the response to hypoxia.

RESULTS

Using reverse transcription-polymerase chain reaction, Ang-2 and Ang-3 mRNA were detected but Ang-1 and Tie-2 transcripts were absent. As assessed by Northern and slot blotting, 8 to 24 hours hypoxia (3% O(2)) significantly increased Ang-2 mRNA levels versus normoxic (21% O(2)) cells and the rate of Ang-2 mRNA degradation was similar in both conditions, consistent with increased transcription. Hypoxia also increased immunoreactive Ang-2 in cell lysates. Hypoxic stimulation of Ang-2 mRNA was significantly reduced by inhibitors of tyrosine kinase (genistein) and protein kinase C (GF109203X), but not by a mitogen-activated protein kinase 1 inhibitor (PD98059). Furthermore, hypoxia coincidentally up-regulated levels of vascular endothelial growth factor (VEGF) mRNA in these cells. Finally, in vivo, immunoreactive Ang-2 was observed in the cores of immature glomeruli of neonatal mice, but immunostaining in this location was absent in four-week postnatal mice.

CONCLUSION

This is the first demonstration that isolated mesangial cells express Ang-2 mRNA and protein and up-regulate Ang-2 in response to hypoxia. We speculate that hypoxia-induced, mesangial-derived Ang-2 and VEGF may have synergistic paracrine roles in the growth of glomerular endothelia during normal development and diseases.

Involvement of endogenous opioidergic neurons in modulation of prolactin secretion in response to mating in the female rat

Mating in female rats induces an acute prolactin (PRL) release within 60 min and twice-daily surges of PRL throughout the first 10 days of pregnancy to maintain luteal function. Little is known about the brain mechanism whereby the vaginocervical stimulation is processed to induce PRL release. Our recent results revealed an increase in Fos expression in the arcuate nucleus (ARC) following mating in the intact estrous rat, suggesting that a neuronal network in the brain area may participate in conveying and integrating the genitosensory stimulation. To further investigate the phenotype of activated neurons in the ARC, the present study examined whether beta-endorphin (beta-END) and/or dopamine (DA) neurons are activated by mating, and if so, whether activation is involved in the mating-induced acute release of PRL and the establishment of the twice-daily surges of PRL. In experiment 1, proestrous rats receiving intromissions (mated group) from males or mounts without intromission (mounted group) were sacrificed along with rats taken directly from their home cage (control group) 60 min after the beginning of mating or mounting. Expression of Fos in beta-END neurons and expression of fos-related antigen (FRA) in DA neurons, which were labeled by tyrosine hydroxylase (TH) antibody in the ARC were examined by double-label immunocytochemistry. In experiment 2, proestrous females with indwelling atrial catheters were mated with males. Naloxone (10 microl/min, 2 mg/10 min), an opiate antagonist, or saline was infused before, during and after mating. Blood samples were collected during the mating session and also at several times 3 days after mating. The results showed that mating induced a significant increase in the percentage of beta-END/Fos colabeled neurons and a significant decrease in the number of beta-END cells in all subdivisions of the ARC. In contrast, neither the percentage of FRA/TH colabeled cells nor the number of TH cells was influenced by mating. Mating induced an acute increase in PRL release in saline-treated control animals within 30 min and a subsequent diurnal surge (18.00 h) and a nocturnal surge of PRL (2.00 h) 3 days after mating. Naloxone infusion during mating blocked the mating-induced acute PRL response and the diurnal surge of PRL 3 days after mating, but affected neither the nocturnal surge of PRL nor the incidence of pregnancy. These results demonstrate that (1) beta-END neurons but not DA neurons in the ARC are activated in response to mating in proestrous rats, and (2) the mating-induced activation of beta-END neurons may participate in the acute response of PRL release to mating and the memory mechanism for the establishment of the diurnal PRL surge, but not the nocturnal PRL surge in early pregnancy. These results lead to a conclusion that endogenous opioid peptides may be involved in the neuronal transmission of genitosensory stimulation to induce PRL secretion.

The role of lung scintigraphy in the diagnosis of nephrotic syndrome with pulmonary embolism

PURPOSE

Patients with nephrotic syndrome (NS) have an increased tendency to develop thrombosis and even to progress to pulmonary embolism (PE). This study was performed to determine the incidence of PE in NS with severe hypoalbuminemia and to investigate the possible role of ventilation-perfusion (V/Q) lung scans to evaluate these patients.

METHODS

Eighty-nine patients with NS (serum albumin concentration < 2 g/dl) and risk factors for PE were studied. In all patients, the probability that PE would develop was assessed based on the results of V/Q lung scans (Xe-133 for ventilation and Tc-99m MAA for perfusion imaging). The lung scans were judged using the modified Prospective Investigation of Pulmonary Embolism Diagnosis criteria. In 25 (28%) patients whose lung scans showed an intermediate or low probability, but for whom there was a strong clinical indication of PE, pulmonary angiography was performed. The patients' clinical symptoms and signs on initial examination were observed. Additional examinations included electrocardiograms, chest radiography, and hematochemical tests such as albumin, blood urea nitrogen, creatinine, cholesterol, triglycerides, fibrinogen, antithrombin III, prothrombin time, and activated partial thromboplastin time.

RESULTS

Based on the findings of lung scans, 19 (21%) of the patients were categorized as having a high probability of PE. However, pulmonary angiography found that 10 (11%) other patients had PE despite having lung scan findings categorized as intermediate or low probability of PE. Except for plasma fibrinogen and antithrombin III levels, neither the clinical symptoms and signs, electrocardiogram findings, chest radiograph results, nor values of hematochemical testing were consistent with the occurrence of PE in these 29 patients.

CONCLUSION

The results of this study suggest that PE is not a rare complication in patients with NS, and is usually clinically silent. In this series, the occurrence of PE did not appear to be always correlated with the clinical or hematochemical severity of NS, except for the association with elevated levels of fibrinogen and antithrombin III. When treating the clinical symptoms of patients with NS, physicians should be alert to the possible complication of PE. Serial V/Q lung scans may provide valuable clues in the evaluation of these patients.

Distribution of prolactin-releasing peptide mRNA in the rat brain

In order to identify the distribution of prolactin-releasing peptide (PrRP) mRNA in the rat brain, we independently cloned cDNA of PrRP. Brains were removed from three adult males, and brains from three females each at 0200 and 1400 h on day 7 of pregnancy were obtained. By the nonradioactive in situ hybridization method, the location of PrRP mRNA was detected in very restricted brain areas. The distribution of PrRP mRNA signals was very similar in both sexes. In the hypothalamus, only the ventral part of the caudal dorsomedial nucleus had PrRP mRNA signals. Other forebrain areas did not show any positive signals. In the medulla oblongata, two discrete areas contained PrRP mRNA signals. No positive signal was found in the rostral part of the medulla oblongata extending to the anterior part of the area postrema. The caudal part of the nucleus of the solitary tract (NTS) had neurons with very strong signals of PrRP mRNA. The reticular nucleus showed a few PrRP mRNA positive neurons. The number of PrRP mRNA positive cells in the NTS was not different between experimental groups, although plasma prolactin levels in these animals were different. This anatomical information on the location of PrRP mRNA in the brain provides the framework to understand the physiological functions of PrRP in vivo.