Loss of YhcB results in dysregulation of coordinated peptidoglycan, LPS and phospholipid synthesis during Escherichia coli cell growth.

The cell envelope is essential for viability in all domains of life. It retains enzymes and substrates within a confined space while providing a protective barrier to the external environment. Destabilising the envelope of bacterial pathogens is a common strategy employed by antimicrobial treatment. However, even in one of the best studied organisms, Escherichia coli, there remain gaps in our understanding of how the synthesis of the successive layers of the cell envelope are coordinated during growth and cell division. Here, we used a whole-genome phenotypic screen to identify mutants with a defective cell envelope. We report that loss of yhcB, a conserved gene of unknown function, results in loss of envelope stability, increased cell permeability and dysregulated control of cell size. Using whole genome transposon mutagenesis strategies, we report the comprehensive genetic interaction network of yhcB, revealing all genes with a synthetic negative and a synthetic positive relationship. These genes include those previously reported to have a role in cell envelope biogenesis. Surprisingly, we identified genes previously annotated as essential that became non-essential in a ΔyhcB background. Subsequent analyses suggest that YhcB functions at the junction of several envelope biosynthetic pathways coordinating the spatiotemporal growth of the cell, highlighting YhcB as an as yet unexplored antimicrobial target.

Genetic interaction mapping highlights key roles of the Tol-Pal complex.

The conserved Tol-Pal trans-envelope complex is important for outer membrane (OM) stability and cell division in Gram-negative bacteria. It is proposed to mediate OM constriction during cell division via cell wall tethering. Yet, recent studies suggest the complex has additional roles in OM lipid homeostasis and septal wall separation. How Tol-Pal facilitates all these processes is unclear. To gain insights into its function(s), we applied transposon-insertion sequencing, and report here a detailed network of genetic interactions with the tol-pal locus in Escherichia coli. We found one positive and > 20 negative strong interactions based on fitness. Disrupting osmoregulated-periplasmic glucan biosynthesis restores fitness and OM barrier function, but not proper division, in tol-pal mutants. In contrast, deleting genes involved in OM homeostasis and cell wall remodeling causes synthetic growth defects in strains lacking Tol-Pal, especially exacerbating OM barrier and/or division phenotypes. Notably, the ΔtolA mutant having additional defects in OM protein assembly (ΔbamB) exhibited severe division phenotypes, even when single mutants divided normally; this highlights the possibility for OM phenotypes to indirectly impact cell division. Overall, our work underscores the intricate nature of Tol-Pal function, and reinforces its key roles in cell wall-OM tethering, cell wall remodeling, and in particular, OM homeostasis.

Mutations in enterobacterial common antigen biosynthesis restore outer membrane barrier function in Escherichia coli tol-pal mutants.

The outer membrane (OM) is an essential component of the Gram-negative bacterial envelope that protects the cells against external threats. To maintain a functional OM, cells require distinct mechanisms to ensure balance of proteins and lipids in the membrane. Mutations in OM biogenesis and/or homeostasis pathways often result in permeability defects, but how molecular changes in the OM affect barrier function is unclear. Here, we seek potential mechanism(s) that can alleviate permeability defects in Escherichia coli cells lacking the Tol-Pal complex, which accumulate excess PLs in the OM. We identify mutations in enterobacterial common antigen (ECA) biosynthesis that re-establish OM barrier function against large hydrophilic molecules, yet did not restore lipid homeostasis. Furthermore, we demonstrate that build-up of biosynthetic intermediates, but not loss of ECA itself, contributes to the rescue. This suppression of OM phenotypes is unrelated to known effects that accumulation of ECA intermediates have on the cell wall. Finally, we reveal that an unusual diacylglycerol pyrophosphoryl-linked lipid species also accumulates in ECA mutants, and might play a role in the rescue phenotype. Our work provides insights into how OM barrier function can be restored independent of lipid homeostasis, and highlights previously unappreciated effects of ECA-related species in OM biology.

The Efficacy and Safety of High-Intensity Focused Ultrasound (HIFU) Therapy for Benign Thyroid Nodules-A Single Center Experience from Singapore.

BACKGROUND: High-intensity focused ultrasound (HIFU) is a recent noninvasive technique of treating thyroid nodules. Our study aims to investigate the efficacy and safety of HIFU in treating benign thyroid nodules. METHODS: This is a retrospective analysis of consecutive patients who underwent HIFU of benign thyroid nodules at our institution from July 2017-2018. All procedures were performed by a single surgeon. Patients were evaluated immediately post-procedure, and at subsequent intervals of 1 week, 1 month, 3 months, and 6 months. The primary endpoint was thyroid nodule volume reduction at 6 months posttreatment. Secondary endpoints were post-procedure local complications. RESULTS: Ten patients with 13 thyroid nodules were included. The median follow-up period was 426 days (range 238-573). Mean maximum diameter reduced from 2.6 cm (±0.8) pretreatment to 1.4 cm (±0.7, P < 0.05) 6 months posttreatment. Mean nodule volume reduced from 5.2 cm3 (±4.2) pretreatment to 1.5 cm3 (±1.3, P = 0.01) 6 months posttreatment. Mean volume reduction ratio (VRR) at 6 months posttreatment was 63.2% (±22.5, P < 0.05), with volume reduction of ≥50% in 10 of 13 (76.9%) nodules. Two nodules (15.4%) showed size increases from 4 months posttreatment. No patients experienced local skin burns or hematomas. Mean pain scores were 1.5 (±1.2) immediate post-procedure, 0.8 (±1.5) at 1 week, and 0.6 (±1.2) at 1 month post-procedure, respectively, with no reports of pain beyond 1 month. Only two (20.0%) patients had early, temporary posttreatment voice hoarseness. CONCLUSION: Our study shows HIFU ablation to be efficacious and safe-with significant thyroid nodule volume reductions, and no significant or prolonged local complications.

Long-term results of a randomized controlled trial of T2 versus T2-T3 ablation in endoscopic thoracic sympathectomy for palmar hyperhidrosis.

BACKGROUND: Despite good short-term results and patient satisfaction with endoscopic thoracic sympathectomy (ETS), there has been much debate on the level of sympathectomy for treatment of palmar hyperhidrosis (PH) in terms of long-term clinical outcomes. OBJECTIVE: The aim of the study was to analyze the long-term recurrence and compensatory hyperhidrosis (CH) rates of ETS, comparing single-level T2 against multi-level T2-T3 ablation in single patients. METHODS: Patients who had undergone treatment for PH with unilateral T2 and contralateral T2-T3 ablation in ETS were retrospectively reviewed. They were subjected to telephone interview using standardized set of interview script and questionnaire with a scoring system similar to hyperhidrosis disease severity scale. All patients were evaluated for comparison of symptom resolution, site and severity of CH, and satisfaction rates. To compare between T2 and T2-T3, the level of sympathectomy on one side is matched to the ipsilateral recurrence of PH and CH occurrence. RESULTS: Twenty-two patients with a mean age of 36.5 years could be reached. The mean follow-up was 8 years (range 38-153 months). The global recurrence rate for PH is 18%. CH was observed in 20 (91%) patients, and trunk compensation was the most common (18/22-82%), followed by lower limb (14/22-64%) and axilla (10/22-45%). Overall, 72.8% (16) of the patients were satisfied with the operation. Among the six patients who were not satisfied, two patients reported recurrence of symptoms, while four patients experienced some form of compensation. There was no absolute difference in the severity of sweating bilaterally for patients who reported recurrence of PH. The site and severity of CH were also bilaterally symmetrical for all patients. CONCLUSION: There was no difference in recurrence rates and CH between single-level (T2) and multi-level (T2-T3) ETSs in the long term.

Is preoperative withdrawal of aspirin necessary in patients undergoing elective inguinal hernia repair?

BACKGROUND: Antiplatelets such as aspirin are widely used to reduce thrombotic events in patients with various cardiovascular comorbidities. Continuing aspirin through noncardiac surgery has been shown to reduce risk of major adverse cardiac events (MACE) but may lead to higher bleeding complications. Inguinal hernia repair is a commonly performed surgical procedure among such patients, but no guideline exists regarding perioperative use of aspirin. OBJECTIVE: We aim to investigate the safety profile of aspirin continuation in the perioperative period in patients undergoing elective primary inguinal hernia repair. METHODS: All patients who underwent elective primary inguinal hernia repair from 2008 to 2015 and were on aspirin preoperatively were identified. The patients were divided into two groups: those who continued aspirin through the morning of the operation and those who were advised to stop aspirin therapy 3-7 days prior to operation. All patients underwent either open Lichtenstein mesh repair or laparoscopic total extra-peritoneal mesh repair. Outcomes measured include intraoperative blood loss, operative time, bleeding complications, wound site complications and MACE. RESULTS: Among 1841 patients who underwent elective primary inguinal hernia mesh repair, 142 (7.7 %) patients were on preoperative aspirin. Fifty-seven patients underwent laparoscopic repair, while 85 underwent open mesh repair. Twenty-seven out of fifty-seven (47.3 %) from the laparoscopic group and 55/85 (64.7 %) from the open group were instructed to stop aspirin (p = 0.040). There were no significant differences between those who stopped aspirin and those who continued in terms of intraoperative blood loss and operative timing. Immediate postoperative bleeding complications and follow-up wound complications were also similar between the two groups. Overall, there were no MACE among those who underwent laparoscopic repair. Three MACE were recorded in the open group (2 stopped vs. 1 continued; p = 0.943). There was no perioperative mortality. CONCLUSION: Continuation of aspirin is safe and should be preferred in patients with higher cardiovascular risk.

Training improves laparoscopic tasks performance and decreases operator workload.

BACKGROUND: It has been postulated that increased operator workload during task performance may increase fatigue and surgical errors. The National Aeronautics and Space Administration-Task Load Index (NASA-TLX) is a validated tool for self-assessment for workload. Our study aims to assess the relationship of workload and performance of novices in simulated laparoscopic tasks of different complexity levels before and after training. METHODS: Forty-seven novices without prior laparoscopic experience were recruited in a trial to investigate whether training improves task performance as well as mental workload. The participants were tested on three standard tasks (ring transfer, precision cutting and intracorporeal suturing) in increasing complexity based on the Fundamentals of Laparoscopic Surgery (FLS) curriculum. Following a period of training and rest, participants were tested again. Test scores were computed from time taken and time penalties for precision errors. Test scores and NASA-TLX scores were recorded pre- and post-training and analysed using paired t tests. One-way repeated measures ANOVA was used to analyse differences in NASA-TLX scores between the three tasks. RESULTS: NASA-TLX score was lowest with ring transfer and highest with intracorporeal suturing. This was statistically significant in both pre-training (p < 0.001) and post-training (p < 0.001). NASA-TLX scores mirror the changes in test scores for the three tasks. Workload scores decreased significantly after training for all three tasks (ring transfer = 2.93, p < 0.001, precision cutting = 3.74, p < 0.001, intracorporeal suturing = 2.98, p < 0.001). CONCLUSION: NASA-TLX score is an accurate reflection of the complexity of simulated laparoscopic tasks in the FLS curriculum. This also correlates with the relationship of test scores between the three tasks. Simulation training improves both performance score and workload score across the tasks.

Charge requirements of lipid II flippase activity in Escherichia coli.

Peptidoglycan (PG) is an extracytoplasmic glycopeptide matrix essential for the integrity of the envelope of most bacteria. The PG building block is a disaccharide-pentapeptide that is synthesized as a lipid-linked precursor called lipid II. The translocation of the amphipathic lipid II across the cytoplasmic membrane is required for subsequent incorporation of the disaccharide-pentapeptide into PG. In Escherichia coli, the essential inner membrane protein MurJ is the lipid II flippase. Previous studies showed that 8 charged residues in the central cavity region of MurJ are crucial for function. Here, we completed the functional analysis of all 57 charged residues in MurJ and demonstrated that the respective positive or negative charge of the 8 aforementioned residues is required for proper MurJ function. Loss of the negative charge in one of these residues, D39, causes a severe defect in MurJ biogenesis; by engineering an intragenic suppressor mutation that restores MurJ biogenesis, we found that this charge is also essential for MurJ function. Because of the low level of homology between MurJ and putative orthologs from Gram-positive bacteria, we explored the conservation of these 8 charged residues in YtgP, a homolog from Streptococcus pyogenes. We found that only 3 positive charges are similarly positioned and essential in YtgP; YtgP possesses additional charged residues within its predicted cavity that are essential for function and conserved among Gram-positive bacteria. From these data, we hypothesize that some charged residues in the cavity region of MurJ homologs are required for interaction with lipid II and/or energy coupling during transport.

Exploring the Implementation of Shared Decision-Making Involving Health Coaches for Diabetes and Hypertension Self-Management: Qualitative Study.

BACKGROUND: An emerging focus on person-centered care has prompted the need to understand how shared decision-making (SDM) and health coaching could support self-management of diabetes and hypertension. OBJECTIVE: This study aims to explore preferences for the scope of involvement of health coaches and health care professionals (HCPs) in SDM and the factors that may influence optimal implementation of SDM from the perspectives of patients and HCPs. METHODS: We conducted focus group discussions with 39 patients with diabetes and hypertension and 45 HCPs involved in their care. The main topics discussed included the roles of health coaches and HCPs in self-management, views toward health coaching and SDM, and factors that should be considered for optimal implementation of SDM that involves health coaches. All focus group discussions were audio recorded, transcribed verbatim, and analyzed using thematic analysis. RESULTS: Participants agreed that the main responsibility of HCPs should be identifying the patient's stage of change and medication education, while health coaches should focus on lifestyle education, monitoring, and motivational conversation. The health coach was seen to be more effective in engaging patients in lifestyle education and designing goal management plans as health coaches have more time available to spend with patients. The importance of a health coach's personal attributes (eg, sufficient knowledge of both medical and psychosocial management of disease conditions) and credentials (eg, openness, patience, and empathy) was commonly emphasized. Participants viewed that addressing the following five elements would be necessary for the optimal implementation of SDM: (1) target population (newly diagnosed and less stable patients), (2) commitment of all stakeholders (discrepancy on targeted times and modality), (3) continuity of care (familiar faces), (4) philosophy of care (person-centered communication), and (5) faces of legitimacy (physician as the ultimate authority). CONCLUSIONS: The findings shed light on the appropriate roles of health coaches vis-à-vis HCPs in SDM as perceived by patients and HCPs. Findings from this study also contribute to the understanding of SDM on self-management strategies for patients with diabetes and hypertension and highlight potential opportunities for integrating health coaches into the routine care process.

Empowering patients with comorbid diabetes and hypertension through a multi-component intervention of mobile app, health coaching and shared decision-making: Protocol for an effectiveness-implementation of randomised controlled trial.

INTRODUCTION: Diabetes and hypertension are prevalent and costly to the health system. We have developed a mobile app (EMPOWER app) which enables remote monitoring and education through personalised nudges. We aim to study the effectiveness of a multi-component intervention comprising the EMPOWER mobile app with health coaching and shared decision-making for diabetes and hypertension. METHODS: We will conduct a two-arm, open-label, pragmatic randomised controlled trial (RCT). Participants with comorbid diabetes and hypertension enrolled from public primary care clinics will be randomised to either intervention or control in a 1:1 ratio. The intervention group participants will have access to health coaching with shared decision-making interventions in addition to the EMPOWER app and their usual primary care. The control group participants will continue to receive usual primary care and will neither receive the EMPOWER app nor health coaching and shared decision-making interventions. Our primary outcome is change in HbA1c level over 9 months. Secondary outcomes include change in systolic blood pressure, quality of life, patient activation, medication adherence, physical activity level, diet, and healthcare cost (direct and indirect) over 9 months. DISCUSSION: Our trial will provide key insights into clinical- and cost-effectiveness of a multi-component intervention comprising EMPOWER mobile app, health coaching and shared decision-making in diabetes and hypertension management. This trial will also offer evidence on cost-effective and sustainable methods for promoting behavioural changes among patients with comorbid diabetes and hypertension. TRIAL REGISTRATION: This study was registered on clintrials.gov on August 3, 2022, with the trial registration number: NCT05486390.

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.

Economic Evaluation of Novel Models of Care for Patients With Acute Medical Problems.

Importance: During COVID-19, Singapore simultaneously experienced a dengue outbreak, and acute hospitals were under pressure to lower bed occupancy rates. This led to new models of care to treat patients with acute, low-severity medical conditions either at home, in a hospital-at-home (HaH) model, or in a clinic-style setting sited at the emergency department in an ambulatory care team (ACT) model, but a reliable cost analysis for these models is lacking. Objective: To compare personnel costs of HaH and ACT with inpatient care. Design, Setting, and Participants: In this economic evaluation study, time-driven activity-based costing was used to compare the personnel cost of inpatient care with treating dengue via HaH and treating chest pain via ACT. Participants were patients with nonsevere dengue and chest pain unrelated to a coronary event admitted via the emergency department to the internal medicine service of a tertiary hospital in Singapore. Exposures: HaH for dengue and ACT for chest pain. Main Outcomes and Measures: A process map was created for the patient journey for a typical patient with each condition. The amount of time personnel spent on delivering care was estimated and the cost per minute determined based on their wages in 2022. The total cost of care was calculated by multiplying the time spent by the per-minute cost of the personnel resource and summing all costs. Results: Compared with inpatient care, HaH used 50% less nursing time (418 minutes, 95% uncertainty interval [UI], 370 to 465 minutes) but 80% more medical time (303 minutes, 95% UI, 270 to 338 minutes) per case of dengue. If implemented nationally, HaH would save an estimated 56 828 SGD per year (95% UI, -169 497 to 281 412 SGD [US $41 856; 95% UI, -$124 839 to $207 268]). The probability that HaH is cost saving was 69.2%. Compared with inpatient care, ACT used 15% less nursing time (296 minutes, 95% UI, 257 to 335 minutes) and 50% less medical time (57 minutes, 95% UI, 46 to 69 minutes) per case of chest pain. If implemented nationally, ACT would save an estimated 1 561 185 SGD per year (95% UI, 1 040 666 to 2 086 518 SGD [US $1 149 862; 95% UI, $766 483 to $1 536 786]). The probability that ACT is cost saving was 100%. Conclusions and Relevance: This economic evaluation found that the HaH and ACT models decreased the overall personnel cost of care. Reorganizing hospital resources may help hospitals reap the benefits of reduced hospital-acquired infections, improved patient recovery, and reduced hospital bed occupancy rates.

Personal Goals, Barriers to Self-Management and Desired mHealth Application Features to Improve Self-Care in Multi-Ethnic Asian Patients with Type 2 Diabetes: A Qualitative Study.

(1) Introduction: The ubiquity of mobile phones suggests the potential of mobile health applications to reach patients with type 2 diabetes and engage them to improve self-care. This study aimed to explore personal goals, barriers to self-management and desired mobile health application features to improve self-care among multi-ethnic Asian patients with type 2 diabetes. (2) Methods: We conducted semi-structured interviews with patients with type 2 diabetes (n = 29). Patients were recruited from a multi-disciplinary center for diabetes and metabolism in Singapore, using a purposive sampling strategy. Various visual materials, collated from existing mobile health application features, were used to facilitate the discussion. Interviews were transcribed verbatim and thematically analyzed. (3) Results: A total of 29 patients participated in 11 focus group discussions or one-on-one interviews. Personal goals for self-management were centered around short-term outcome expectancy, such as better glucose control and a reduced number of medications. Self-management was hampered by competing priorities and limited healthy food options when at work, while a lack of tailored advice from healthcare providers further diminished competence. The desired mobile health app features to improve self-care behaviors included quantifiable goal-setting, personalized nudges based on tracked data, built-in resources from credible sources, in-app social support through virtual interaction with peers and healthcare providers, technology-driven novel data logging and user-defined nudges. (4) Conclusions: We identified a set of app features that may foster motivation to engage in lifestyle modification for patients with T2DM. The findings serve to inform the design of artificial intelligence-enabled mobile health application intervention aimed at improving diabetes self-care.

EMPOWERing Patients With Diabetes Using Profiling and Targeted Feedbacks Delivered Through Smartphone App and Wearable (EMPOWER): Protocol for a Randomized Controlled Trial on Effectiveness and Implementation.

Introduction: Type 2 diabetes mellitus (T2DM) poses huge burden and cost on the healthcare system. Mobile health (mHealth) interventions that incorporate wearables may be able to improve diabetes self-management. The aim of this randomized controlled trial (RCT) is to investigate the clinical and cost-effectiveness of personalized educational and behavioral interventions delivered through an EMPOWER mobile application (app) among patients with T2DM. Methods: This is a parallel two-arm randomized controlled trial (RCT). Patients with T2DM recruited from primary care will be randomly allocated in a 1:1 ratio to either intervention or control group. The intervention group will receive personalized educational and behavioral interventions through the EMPOWER app in addition to their usual clinical care. The control group will receive the usual clinical care for their T2DM but will not have access to the EMPOWER app. Our primary outcome is patient activation score at 12 months. Secondary outcomes will include HbA1c, physical activity level and diet throughout 12 months; quality of life (QoL), medication adherence, direct healthcare cost and indirect healthcare cost at 6 and 12 months. Discussion: This RCT will provide valuable insights into the effectiveness and implementation of personalized educational and behavioral interventions delivered through mobile application in T2DM management. Findings from this study can help to achieve sustainable and cost-effective behavioral change in patients with T2DM, and this can be potentially scaled to other chronic diseases such as hypertension and dyslipidemia.

Persistent Anxiety Is Associated with Higher Glycemia Post-Transition to Adult Services in Asian Young Adults with Diabetes.

BACKGROUND: There is little longitudinal information on psychological burden and metabolic outcomes in young adults with diabetes (YAD) in Asia. We aimed to evaluate the association between psychological status and glycemia at baseline and 2 years following transition in a cohort of YAD in Singapore. METHODS: Subjects with type 1 diabetes mellitus (T1DM) and type 2 diabetes mellitus (T2DM), aged 17 to 25 years, were recruited from the YAD clinic in Singapore General Hospital. The Hospital Anxiety and Depression and Problem Areas for Diabetes scales were administered at transition (baseline) and at 18 to 24 months. Glycosylated hemoglobin (HbA1c) assessed during routine visits was tracked longitudinally. RESULTS: A total of 98 T1DM (74.8%) and 33 T2DM (25.2%) subjects were recruited between January 2011 and November 2017. At baseline, mean HbA1c was 8.6%±1.7%. Only 26.0% achieved HbA1c of ≤7.5% and 16.8% achieved HbA1c of <7%. At baseline, prevalence of anxiety was 29.8%. At 24 months, 14.1% had persistent anxiety. Those with persistent anxiety had the highest mean HbA1c, particularly at 6 months (persistently anxious vs. persistently non-anxious: 9.9%±1.2% vs. 8.2%±1.9%, P=0.009). At baseline, 9.2% of subjects had depression. This group also had poorer glycemia at baseline (HbA1c of depressed vs non-depressed: 9.6%±2.1% vs. 8.5%±1.6%, P=0.04), which persisted up to 24 months. CONCLUSION: The majority of YAD in Singapore have suboptimal glycemia. Psychological distress is a critical harbinger of poorer metabolic outcomes.

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.

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.

Epidemiologic Characteristics of Multimorbidity and Sociodemographic Factors Associated With Multimorbidity in a Rapidly Aging Asian Country.

Importance: Multimorbidity is a growing health care problem in aging societies and is strongly associated with epidemiologic characteristics and sociodemographic factors. Knowledge of these associations is important for the design of effective preventive and management strategies. Objectives: To determine the association between multimorbidity and sociodemographic factors (age, socioeconomic status [SES], sex, and race/ethnicity) and the association between mental health diseases and physical diseases, as well as their implications for the types and costs of health care use. Design, Setting, and Participants: This population-based cross-sectional study used deidentified Singapore Eastern Regional Health System data collected between January 1, 2012, and December 31, 2016. Patients who were alive as of January 1, 2016, and residing in the Regional Health System region in 2016 (N = 1 181 024) were included. Patients who had no year of birth records (n = 573), were born in 2017 (n = 93), or died before January 1, 2016 (n = 47 322), were excluded. Main Outcomes and Measures: Multimorbidity, age, sex, SES, mental health, race/ethnicity, and health care use. Results: In the study population of 1 181 024 individuals, the mean (SD) age was 39.6 (22.1) years, 51.2% were women, 70.1% were Chinese, 7.1% were Indian, 13.5% were Malayan, and 9.3% were other races/ethnicities. Multimorbidity, present in 26.2% of the population, was more prevalent in female (26.8%; 95% CI, 26.7%-26.9%) than in male (25.6%; 95% CI, 25.5%-25.7%) patients and among patients with low SES (41.6%) than those with high SES (20.1%). Mental health diseases were significantly more prevalent among individuals with low SES (5.2%; 95% CI, 5.1%-5.2%) than high SES (2.1%; 95% CI, 2.0%-2.1%; P < .001). The 3 most prevalent disease combinations were chronic kidney disease and hypertension, chronic kidney disease and lipid disorders, and hypertension and lipid disorders. Although chronic kidney disease, hypertension, lipid disorders, and type 1 and/or type 2 diabetes-related diseases had a low cost per capita, the large number of patients with these conditions caused the overall proportion of the cost incurred by health care use to be more than twice that incurred in other diseases. Conclusions and Relevance: These findings emphasize the association between multimorbidity and sociodemographic factors such as increasing age, lower SES, female sex, and increasing number of mental disorders. Health care policies need to take sociodemographic factors into account when tackling multimorbidity in a population.

Predictors of survival outcome following radical gastrectomy for gastric cancer.

BACKGROUND: Radical surgery with adjuvant therapy is now the standard treatment for locally advanced gastric cancer. However, the best regimen for adjuvant therapy remains controversial. We aim to determine the predictors of survival outcome of gastric cancer patients who underwent curative surgery with or without adjuvant therapy in our institution. METHODS: All patients who received surgery for gastric cancer from years 2000 to 2015 were studied using a prospective gastric cancer database at the National University Hospital, Singapore. RESULTS: A total of 405 patients underwent radical gastrectomy with curative intent. Seventy-eight percent received extended lymphadenectomy (≥D1). R0 resection was achieved in 377 patients (93%) with 30-day mortality rate of 1.7%. There was no significant difference in the complication rate between D1 and extended lymphadenectomy group. One hundred and forty-five patients (36%) received adjuvant therapy. With a median follow-up of 5.9 years, the 5-year disease-free survival for stage I to IV patients were 78%, 58%, 27% and 9%, respectively. Among the 141 patients with known recurrences, the first site of recurrence was 38% distant, 24% locoregional, 20% peritoneal and the rest were multiple sites. Stage of disease, adjuvant therapy, extent of lymphadenectomy, post-operative complication and approach of surgery were independent risk factors for long-term survival. CONCLUSIONS: Stage of disease, adjuvant therapy, extent of lymphadenectomy, post-operative complication and approach of surgery are significant predictors for long-term survival. Adequate and safe surgery to allow adjuvant therapy should be the goal of all surgeons for our gastric cancer patients.

Predictors of thyroxine replacement following hemithyroidectomy in a south east Asian cohort.

BACKGROUND: Thyroxine replacement following a hemithyroidectomy is not commonly discussed during consent for the procedure as the risk of hypothyroidism is perceived to be low. METHODS: Retrospective review of 901 patients who underwent hemithyroidectomy at a tertiary referral institution during the period January 2000 to December 2015. The main outcome studied was the overall incidence of hypothyroidism and the associated risk factors. RESULTS: Hypothyroidism developed in 123 (13%) patients and 94 patients (10%) required hormone supplementation over a mean follow up of 21 months (range 1-168 months). Preoperative TSH of more than 2.5 was seen in 38 of 123 (31%) of patients. Presence of diffuse thyroiditis was the only independent risk factor on multivariate analysis (P = 0.002) found to be associated with the development of hypothyroidism. CONCLUSION: After thyroid lobectomy, approximately one in 10 patients requiring thyroid hormone treatment for hypothyroidism. Presence of diffuse thyroiditis is a significant risk factor for hypothyroidism.