Parathyroidectomy for Normocalcemic Primary Hyperparathyroidism is Associated with Improved Bone Mineral Density Regardless of Postoperative Parathyroid Hormone Levels.

BACKGROUND: Biochemical cure in normocalcemic primary hyperparathyroidism (nPHPT) is defined as parathyroid hormone (PTH) level normalization 6 months after parathyroidectomy. However, recent studies show that a significant number of nPHPT patients have persistent PTH elevation postoperatively. We sought to correlate changes in PTH levels with skeletal outcomes after parathyroidectomy in nPHPT patients. METHODS: Adult patients who underwent parathyroidectomy at a tertiary referral center for sporadic PHPT between 2010 and 2020 were reviewed. Pre- and postoperative (6 months, 18 months, and last follow-up) laboratory and bone mineral densities (BMD) were recorded. Primary outcome was 18-month postoperative BMD change in the lumbar spine (LS), total hip (TH) and femoral neck (FN) in normocalcemic and hypercalcemic PHPT (hPHPT) patients. RESULTS: Of 661 patients included, 68 had nPHPT. nPHPT patients frequently had multigland disease (31% vs. 18%, p = 0.014), more bilateral cervical explorations (22% vs. 13%, p = 0.042), and fewer achieved biochemical cure (76% vs. 95%, p < 0.001) than hPHPT patients. Twenty-eight nPHPT patients had BMD data for comparison. Overall, nPHPT patients had improvement in the LS (1.84%, p = 0.002) and TH (1.64%, p = 0.014). When stratified by postoperative PTH levels, nPHPT patients with persistent PTH elevation had more BMD improvement at the TH than those who normalized PTH (3.73% vs. - 0.83%, p = 0.017). There was no difference in improvement at the LS or FN (p = NS). CONCLUSION: Parathyroidectomy is associated with improved BMD in nPHPT patients with bone disease. Although one in four nPHPT patients had elevated postoperative PTH levels persisting throughout the study, BMD improvement was still seen regardless of postoperative PTH level normalization.

Trends and Outcomes of Surgical Management of Primary Papillary Carcinoma in the Pediatric Population.

BACKGROUND: Childhood papillary thyroid cancer is more aggressive than carcinomas in adults. Current American Thyroid Association pediatric guidelines recommend a total or near-total thyroidectomy for all pediatric patients without gross evidence of lymph node metastases. Our objective is to analyze trends in the surgical management of pediatric papillary thyroid cancer and assess how well the guidelines are implemented. METHODS: A retrospective cohort study of pediatric patients (ages 19 y and under) who underwent a thyroidectomy was conducted using the Surveillance, Epidemiology, and End Results database 2006-2017. Procedure type was classified as lobectomy or less and subtotal or total thyroidectomy. Descriptive statistics to illustrate patient and tumor characteristics as well as chi-square analysis to evaluate frequency of treatment with total thyroidectomies versus lobectomy or less were performed. Logistic regression analysis controlling for age, sex, size of tumor, rural versus urban institutions, and surgery year was conducted to identify factors predictive of procedure type. RESULTS: A total of 2271 children underwent surgical management of papillary thyroid cancer between 2006 and 2017. Most patients received a subtotal or total thyroidectomy as surgical management (n = 2,085, 91.8%). One hundred eighty-six patients (8.2%) received a lobectomy or less. The number of lobectomies or less increased with time, with 41 (6.6%) patients between 2006 and 2009, 98 (8.0%) between 2009 and 2015, and 47 (11.1%) between 2016 and 2017 (P = 0.03). Mortality rates were low (n = 15, 0.7%). On logistic regression analysis, later stages, larger sizes, and earlier operative years were predictive of a near-total or total thyroidectomy. CONCLUSIONS: Despite the American Thyroid Association Guidelines recommending a total thyroidectomy for pediatric well-differentiated thyroid cancer, the results of this study demonstrate that thyroid lobectomies are being performed in increasing frequency for smaller tumors in earlier stages of disease. Further investigation of whether this trend actually affects the outcomes in this patient cohort is needed.

A Multidisciplinary Head-to-Head Comparison of American College of Radiology Thyroid Imaging and Reporting Data System and American Thyroid Association Ultrasound Risk Stratification Systems.

BACKGROUND: Ultrasound plays a critical role in evaluating thyroid nodules. We compared the performance of the two most popular ultrasound malignancy risk stratification systems, the 2015 American Thyroid Association (ATA) guidelines and the American College of Radiology Thyroid Imaging and Reporting Data System (ACR TI-RADS). MATERIALS AND METHODS: We retrospectively identified 250 thyroid nodules that were surgically removed from 137 patients. Their ultrasound images were independently rated using both ATA and ACR TI-RADS by six raters with expertise in ultrasound interpretation. For each system, we generated a receiver operating characteristic curve and calculated the area under the curve (AUC). RESULTS: Sixty-five (26%) nodules were malignant. There was "fair agreement" among raters for both ATA and ACR TI-RADS. Our observed malignancy risks for ATA and ACR TI-RADS categories were similar to expected risk thresholds with a few notable exceptions including the intermediate ATA risk category and the three highest risk categories for ACR TI-RADS. Biopsy of 226 of the 250 nodules would be indicated by ATA guidelines based on nodule size and mean ATA rating. One hundred forty-six nodules would be biopsied based on ACR TI-RADS. The sensitivity, specificity, and negative and positive predictive values were 92%, 10%, 79%, and 27%, respectively, for ATA and 74%, 47%, 84%, and 33%, respectively, for ACR TI-RADS. The AUC for ATA was 0.734 and for ACR TI-RADS was 0.718. CONCLUSION: Although both systems demonstrated good diagnostic performance, ATA guidelines resulted in a greater number of thyroid biopsies and exhibited more consistent malignancy risk prediction for higher risk categories. IMPLICATIONS FOR PRACTICE: With the rising incidence of thyroid nodules, the need for accurate detection of malignancy is important to avoid the overtreatment of benign nodules. Ultrasonography is one of the key tools for the evaluation of thyroid nodules, although the use of many different ultrasound risk stratification systems is a hindrance to clinical collaboration in everyday practice and the comparison of data in research. The first step toward the development of a universal thyroid nodule ultrasound malignancy risk stratification system is to better understand the strengths and weaknesses of the current systems in use.

Genomic comparison of Trypanosoma conorhini and Trypanosoma rangeli to Trypanosoma cruzi strains of high and low virulence.

BACKGROUND: Trypanosoma conorhini and Trypanosoma rangeli, like Trypanosoma cruzi, are kinetoplastid protist parasites of mammals displaying divergent hosts, geographic ranges and lifestyles. Largely nonpathogenic T. rangeli and T. conorhini represent clades that are phylogenetically closely related to the T. cruzi and T. cruzi-like taxa and provide insights into the evolution of pathogenicity in those parasites. T. rangeli, like T. cruzi is endemic in many Latin American countries, whereas T. conorhini is tropicopolitan. T. rangeli and T. conorhini are exclusively extracellular, while T. cruzi has an intracellular stage in the mammalian host. RESULTS: Here we provide the first comprehensive sequence analysis of T. rangeli AM80 and T. conorhini 025E, and provide a comparison of their genomes to those of T. cruzi G and T. cruzi CL, respectively members of T. cruzi lineages TcI and TcVI. We report de novo assembled genome sequences of the low-virulent T. cruzi G, T. rangeli AM80, and T. conorhini 025E ranging from ~ 21-25 Mbp, with ~ 10,000 to 13,000 genes, and for the highly virulent and hybrid T. cruzi CL we present a ~ 65 Mbp in-house assembled haplotyped genome with ~ 12,500 genes per haplotype. Single copy orthologs of the two T. cruzi strains exhibited ~ 97% amino acid identity, and ~ 78% identity to proteins of T. rangeli or T. conorhini. Proteins of the latter two organisms exhibited ~ 84% identity. T. cruzi CL exhibited the highest heterozygosity. T. rangeli and T. conorhini displayed greater metabolic capabilities for utilization of complex carbohydrates, and contained fewer retrotransposons and multigene family copies, i.e. trans-sialidases, mucins, DGF-1, and MASP, compared to T. cruzi. CONCLUSIONS: Our analyses of the T. rangeli and T. conorhini genomes closely reflected their phylogenetic proximity to the T. cruzi clade, and were largely consistent with their divergent life cycles. Our results provide a greater context for understanding the life cycles, host range expansion, immunity evasion, and pathogenesis of these trypanosomatids.

The truth about metagenomics: quantifying and counteracting bias in 16S rRNA studies.

BACKGROUND: Characterizing microbial communities via next-generation sequencing is subject to a number of pitfalls involving sample processing. The observed community composition can be a severe distortion of the quantities of bacteria actually present in the microbiome, hampering analysis and threatening the validity of conclusions from metagenomic studies. We introduce an experimental protocol using mock communities for quantifying and characterizing bias introduced in the sample processing pipeline. We used 80 bacterial mock communities comprised of prescribed proportions of cells from seven vaginally-relevant bacterial strains to assess the bias introduced in the sample processing pipeline. We created two additional sets of 80 mock communities by mixing prescribed quantities of DNA and PCR product to quantify the relative contribution to bias of (1) DNA extraction, (2) PCR amplification, and (3) sequencing and taxonomic classification for particular choices of protocols for each step. We developed models to predict the "true" composition of environmental samples based on the observed proportions, and applied them to a set of clinical vaginal samples from a single subject during four visits. RESULTS: We observed that using different DNA extraction kits can produce dramatically different results but bias is introduced regardless of the choice of kit. We observed error rates from bias of over 85% in some samples, while technical variation was very low at less than 5% for most bacteria. The effects of DNA extraction and PCR amplification for our protocols were much larger than those due to sequencing and classification. The processing steps affected different bacteria in different ways, resulting in amplified and suppressed observed proportions of a community. When predictive models were applied to clinical samples from a subject, the predicted microbiome profiles were better reflections of the physiology and diagnosis of the subject at the visits than the observed community compositions. CONCLUSIONS: Bias in 16S studies due to DNA extraction and PCR amplification will continue to require attention despite further advances in sequencing technology. Analysis of mock communities can help assess bias and facilitate the interpretation of results from environmental samples.

Lyn but not Fyn kinase controls IgG-mediated systemic anaphylaxis.

Anaphylaxis is a rapid, life-threatening hypersensitivity reaction. Until recently, it was mainly attributed to histamine released by mast cells activated by allergen crosslinking (XL) of FcεRI-bound allergen-specific IgE. However, recent reports established that anaphylaxis could also be triggered by basophil, macrophage, and neutrophil secretion of platelet-activating factor subsequent to FcγR stimulation by IgG/Ag complexes. We have investigated the contribution of Fyn and Lyn tyrosine kinases to FcγRIIb and FcγRIII signaling in the context of IgG-mediated passive systemic anaphylaxis (PSA). We found that mast cell IgG XL induced Fyn, Lyn, Akt, Erk, p38, and JNK phosphorylation. Additionally, IgG XL of mast cells, basophils, and macrophages resulted in Fyn- and Lyn-regulated mediator release in vitro. FcγR-mediated activation was enhanced in Lyn-deficient (knockout [KO]) cells, but decreased in Fyn KO cells, compared with wild-type cells. More importantly, Lyn KO mice displayed significantly exacerbated PSA features whereas no change was observed for Fyn KO mice, compared with wild-type littermates. Intriguingly, we establish that mast cells account for most serum histamine in IgG-induced PSA. Taken together, our findings establish pivotal roles for Fyn and Lyn in the regulation of PSA and highlight their unsuspected functions in IgG-mediated pathologies.

Intraoperative Adjuncts in Thyroid Surgery.

Thyroidectomy is relatively safe and often can be done as a minimally invasive procedure. Although they may be associated with a learning curve, thoughtful use of intraoperative adjuncts such as energy devices, recurrent laryngeal nerve monitoring, and parathyroid autofluorescence have the potential to make incremental improvements in the safety and efficiency of thyroid surgery. Perhaps many of these adjuncts may be of greatest benefit when used routinely by less experienced surgeons or selectively in higher-risk operations, although their adoption in practice continues to increase overall.

Beyond the three P's: adrenal involvement in MEN1.

Adrenal lesions (ALs) are often detected in patients with multiple endocrine neoplasia type 1 (MEN1). However, they are not well described in MEN1, making their clinical management unclear. This study examined the prevalence and outcomes of ALs found in MEN1. We performed a retrospective chart review of patients diagnosed with MEN1 from 1990 to 2021. ALs were diagnosed using abdominal or thoracic imaging and classified as being unilateral or bilateral, having single or multiple nodules, and as having diffuse enlargement or not. Measurable nodular lesions were analyzed for their size and growth over time. Patients' clinical and radiographic characteristics were collected. We identified 382 patients with MEN1, 89 (23.3%) of whom had ALs. The mean age at detection was 47 ± 11.9 years. We documented 101 measurable nodular lesions (mean size, 17.5 mm; range, 3-123 mm). Twenty-seven nodules (26.7%) were smaller than 1 cm. Watchful waiting was indicated in 79 (78.2%) patients, of whom 28 (35.4%) had growing lesions. Functional lesions were diagnosed in 6 (15.8%) of 38 that had functional work-up (diagnoses: pheochromocytoma (n = 2), adrenocorticotropic hormone-dependent hypercortisolism (n = 2), hyperandrogenism (n = 1), hyperaldosteronism (n = 1)); surgery was indicated for 5 (83.3%; n = 12 nodules), 2 of whom had bilateral, diffuse adrenal enlargement. Two patients were diagnosed with adrenocortical carcinoma and two with neoplasms of uncertain malignant potential. Radiographic or clinical progression of ALs is uncommon. Malignancy should be suspected on the basis of a lesion's growth rate and size. A baseline hormonal work-up is recommended, and no further biochemical work-up is suggested when the initial assessment shows nonfunctioning lesions.

Advances in Endocrine Surgery.

Recent changes in the landscape of endocrine surgery include a shift from total thyroidectomy for almost all patients with papillary thyroid cancer to the incorporation of thyroid lobectomy for well-selected patients with low-risk disease; minimally invasive parathyroidectomy with, and potentially without, intraoperative parathyroid hormone monitoring for patients with well-localized primary hyperparathyroidism; improvement in the management of parathyroid cancer with the incorporation of immune checkpoint blockade and/or targeted therapies; and the incorporation of minimally invasive techniques in the management of patients with benign tumors and selected secondary malignancies of the adrenal gland.

Pheochromocytoma recurrence in hereditary disease: does a cortical-sparing technique increase recurrence rate?

BACKGROUND: Posterior retroperitoneoscopic adrenalectomy is an appealing approach for patients with hereditary pheochromocytoma and lends well to cortex preservation. We sought to examine pheochromocytoma recurrence in patients with hereditary pheochromocytoma in the era of posterior retroperitoneoscopic adrenalectomy and evaluate the predictors of recurrence. METHODS: Patients with hereditary pheochromocytoma who underwent adrenalectomy for pheochromocytoma between 1995 and 2020 with biochemical cure and follow-up >1 year were identified. Recurrence was defined as plasma metanephrines above the upper limit of normal with radiographic evidence of disease in the ipsilateral adrenal bed. RESULTS: Seventy-eight hereditary pheochromocytoma patients (median age = 32.4 years; 60.3% women) underwent 114 adrenalectomies for pheochromocytoma. Of these patients, 40 had multiple endocrine neoplasia type 2A (51.3%), 10 had multiple endocrine neoplasia type B (12.8%), 17 had von Hippel-Lindau disease (21.8%), and 11 had neurofibromatosis type 1 (14.1%). Thirty-eight adrenalectomies (33.3%) were performed before the introduction of posterior retroperitoneoscopic adrenalectomy and 76 (66.7%) after. Cortical-sparing technique was performed in 62 (54.4%) adrenalectomies, with no difference in its use before and after posterior retroperitoneoscopic adrenalectomy introduction (P > .05). During a median follow-up of 80.7 months (interquartile range 43.4-151.2), 12 ipsilateral recurrences (10.5%) were identified. There was no difference in recurrence before and after the introduction of posterior retroperitoneoscopic adrenalectomy or by surgical technique or approach of the entire cohort (P > .05). Recurrence was more common in those with RET M918T mutation (23.5% vs 8.2%; P = .05). Patients with RET M918T mutations had a shorter recurrence-free survival (P = .013). On multivariate analysis, only RET M918T mutation was independently associated with an increased recurrence risk (hazard ratio = 4.30; 95% confidence interval, 1.26-14.66; P = .019). CONCLUSION: The introduction of posterior retroperitoneoscopic adrenalectomy did not influence the recurrence rate after adrenalectomy for hereditary pheochromocytoma patients. Patients with a RET M918T germline mutation are at increased risk for pheochromocytoma recurrence and may benefit from initial total adrenalectomy.

Primary Hyperparathyroidism Is Associated With Shorter QTc Intervals, but Not Arrhythmia.

CONTEXT: Primary hyperparathyroidism (PHPT) is associated with subclinical cardiovascular disease, but data regarding cardiac conduction abnormalities are limited. OBJECTIVE AND DESIGN: Retrospective cross-sectional comparison of cardiac conduction in patients with PHPT or thyroid disease (TD). PARTICIPANTS AND SETTING: Patients ≥40 years old who underwent parathyroidectomy or thyroidectomy at a single tertiary institution from 2013 to 2018. METHODS AND OUTCOMES: Demographics and preoperative electrocardiogram (EKG) parameters were compared using the Mann-Whitney U, chi-square test, and linear regression. RESULTS: A total of 1242 patients were included: 49.8% PHPT (n = 619) and 50.2% TD (n = 623). Median age was 60.5 years [interquartile range (IQR) 53.6-67.9]. Compared to controls, PHPT patients had higher median serum calcium [10.7 mg/dL (IQR 10.4-11.1) vs 9.5 mg/dL (IQR 9.3-9.8), P < 0.001] as expected, as well as, a higher prevalence of hyperlipidemia (49% vs 36%, P < 0.001) and hypertension (50.1% vs 42.2%, P < 0.01). Based on EKG, there was no difference in PR interval or the prevalence of arrhythmia, atrioventricular block, ST segment/T wave changes, premature ventricular complexes, right bundle branch block, or left bundle branch block after adjusting for covariates. The PHPT group had a lower mean corrected QT interval (414 ± 24) ms vs 422 ± 24 ms, P < 0.01), adjusted for covariates. Serum calcium predicted QTc independently of age, sex, and other covariates. CONCLUSIONS: In the largest study to date, PHPT patients had shorter QTc intervals compared to TD controls but no increased prevalence of arrhythmia based on preoperative EKG.

Anaplasma phagocytophilum infects mast cells via alpha1,3-fucosylated but not sialylated glycans and inhibits IgE-mediated cytokine production and histamine release.

Mast cells are sentinels for infection. Upon exposure to pathogens, they release their stores of proinflammatory cytokines, chemokines, and histamine. Mast cells are also important for the control of certain tick-borne infections. Anaplasma phagocytophilum is an obligate intracellular tick-transmitted bacterium that infects neutrophils to cause the emerging disease granulocytic anaplasmosis. A. phagocytophilum adhesion to and infection of neutrophils depend on sialylated and α1,3-fucosylated glycans. We investigated the hypotheses that A. phagocytophilum invades mast cells and inhibits mast cell activation. We demonstrate that A. phagocytophilum binds and/or infects murine bone marrow-derived mast cells (BMMCs), murine peritoneal mast cells, and human skin-derived mast cells. A. phagocytophilum infection of BMMCs depends on α1,3-fucosylated, but not sialylated, glycans. A. phagocytophilum binding to and invasion of BMMCs do not elicit proinflammatory cytokine secretion. Moreover, A. phagocytophilum-infected cells are inhibited in the release of tumor necrosis factor alpha (TNF-α), interleukin 6 (IL-6), IL-13, and histamine following stimulation with IgE or antigen. Thus, A. phagocytophilum mitigates mast cell activation. These findings potentially represent a novel means by which A. phagocytophilum usurps host defense mechanisms and shed light on the interplay between mast cells and vector-borne bacterial pathogens.

The Anaplasma phagocytophilum-occupied vacuole selectively recruits Rab-GTPases that are predominantly associated with recycling endosomes.

Anaplasma phagocytophilum is an obligate intracellular bacterium that infects neutrophils to reside within a host cell-derived vacuole. The A. phagocytophilum-occupied vacuole (ApV) fails to mature along the endocytic pathway and is non-fusogenic with lysosomes. Rab GTPases regulate membrane traffic. To better understand how the bacterium modulates the ApV's selective fusogencity, we examined the intracellular localization of 20 green fluorescent protein (GFP) or red fluorescent protein (RFP)-tagged Rab GTPases in A. phagocytophilum-infected HL-60 cells. GFP-Rab4A, GFP-Rab10, GFP-Rab11A, GFP-Rab14, RFP-Rab22A and GFP-Rab35, which regulate endocytic recycling, and GFP-Rab1, which mediates endoplasmic reticulum to Golgi apparatus trafficking, localize to the ApV. Fluorescently tagged Rabs are recruited to the ApV upon its formation and remain associated throughout infection. Endogenous Rab14 localizes to the ApV. Tetracycline treatment concomitantly promotes loss of recycling endosome-associated GFP-Rabs and acquisition of GFP-Rab5, GFP-Rab7, and the lysosomal marker, LAMP-1. Wild-type and GTPase- deficient versions, but not GDP-restricted versions of GFP-Rab1, GFP-Rab4A and GFP-Rab11A, localize to the ApV. Strikingly, GFP-Rab10 recruitment to the ApV is guanine nucleotide-independent. These data establish that A. phagocytophilum selectively recruits Rab GTPases that are primarily associated with recycling endosomes to facilitate its intracellular survival and implicate bacterial proteins in regulating Rab10 membrane cycling on the ApV.

Anaplasma phagocytophilum APH_1387 is expressed throughout bacterial intracellular development and localizes to the pathogen-occupied vacuolar membrane.

Obligate vacuolar pathogens produce proteins that localize to the host cell-derived membranes of the vacuoles in which they reside, yielding unique organelles that are optimally suited for pathogen survival. Anaplasma phagocytophilum is an obligate vacuolar bacterium that infects neutrophils and causes the emerging and potentially fatal disease human granulocytic anaplasmosis. Here we identified APH_1387 as the first A. phagocytophilum-derived protein that associates with the A. phagocytophilum-occupied vacuolar membrane (AVM). APH_1387, also referred to as P100, is a 61.4-kDa acidic protein that migrates with an apparent molecular weight of 115 kDa on SDS-PAGE gels. It carries 3 tandem direct repeats that comprise 58% of the protein. Each APH_1387 repeat carries a bilobed hydrophobic alpha-helix domain, which is a structural characteristic that is consistent with the structure of chlamydia-derived proteins that traverse inclusion membranes. APH_1387 is not detectable on the surfaces of A. phagocytophilum dense core organisms bound at the HL-60 cell surface, but abundant APH_1387 is detected on the surfaces of intravacuolar reticulate cell and dense core organisms. APH_1387 accumulates on the AVM throughout infection. It associates with the AVM in human HL-60, THP-1, and HMEC-1 cells and tick ISE6 cells. APH_1387 is expressed and localizes to the AVM in neutrophils recovered from A. phagocytophilum-infected mice. This paper presents the first direct evidence that A. phagocytophilum actively modifies its host cell-derived vacuole.

Anaplasma phagocytophilum APH_0032 is expressed late during infection and localizes to the pathogen-occupied vacuolar membrane.

Anaplasma phagocytophilum infects neutrophils and myeloid, endothelial, and tick cell lines to reside within a host cell-derived vacuole that is indispensible for its survival. Here, we identify APH_0032 as an Anaplasma-derived protein that associates with the A. phagocytophilum-occupied vacuolar membrane (AVM). APH_0032 is a 66.1 kDa acidic protein that electrophoretically migrates with an apparent molecular weight of 130 kDa. It contains a predicted transmembrane domain and tandemly arranged direct repeats that comprise 46% of the protein. APH_0032 is undetectable on Anaplasma organisms bound to the surfaces of HL-60 cells, but is detected on the AVM and surfaces of intravacuolar bacteria beginning 24 h post-infection. APH_0032 localizes to the AVM in HL-60, THP-1, HMEC-1, and ISE6 cells. APH_0032, along with APH_1387, which encodes a confirmed AVM protein, is transcribed during A. phagocytophilum infection of tick salivary glands and murine neutrophils. APH_0032 localizes to the AVM in neutrophils recovered from infected mice. The Legionella pneumophila Dot/IcM type IV secretion system (T4SS) can heterologously secrete a CyaA-tagged version of the A. phagocytophilum VirB/D T4SS effector, AnkA, but fails to secrete CyaA-tagged APH_0032 or APH_1387. These data confirm APH_0032 as an Anaplasma-derived AVM protein and hint that neither it nor APH_1387 are T4SS effectors.

A stepwise analysis of the diagnostic algorithm for the prediction of malignancy in thyroid nodules.

BACKGROUND: The evaluation of the malignancy risk of thyroid nodules involves clinical factors, sonographic characteristics, cytopathology, and molecular profiling. Altogether, this algorithm can be costly and time consuming. We evaluated the stepwise contribution of each diagnostic step toward an accurate prediction of malignancy. METHODS: A retrospective study of dominant nodules of 137 patients who underwent surgical excision was performed. A baseline logistic regression model for predicting malignancy was regressed on clinical factors. In a stepwise fashion, the 2015 American Thyroid Association ultrasound risk stratification, Bethesda classification of fine-needle aspiration biopsies, and molecular profiling were added to the baseline model and the significance of each step analyzed using likelihood ratio test. Receiver operating characteristic curves were calculated for each model. RESULTS: The addition of American Thyroid Association risk stratification and Bethesda classification to preceding models were statistically significant (P < .001). The addition of molecular profiling (as a strategy independent of a particular test) was not significant (P = .812). The areas under the curve of the baseline model and models sequentially including American Thyroid Association stratification, cytopathology, and molecular profiling were 0.76, 0.85, 0.91, and 0.91, respectively. CONCLUSION: Clinical factors, sonographic characteristics, and cytopathology are sufficiently accurate in predicting malignancy risk of most thyroid nodules.

Analysis of a unique interaction between the complement regulatory protein factor H and the periodontal pathogen Treponema denticola.

Treponema denticola, a spirochete associated with periodontitis, is abundant at the leading edge of subgingival plaque, where it interacts with gingival epithelia. T. denticola produces a number of virulence factors, including dentilisin, a protease which is cytopathic to host cells, and FhbB, a unique T. denticola lipoprotein that binds complement regulatory proteins. Earlier analyses suggested that FhbB specifically bound to factor H (FH)-like protein 1 (FHL-1). However, by using dentilisin-deficient mutants of T. denticola, we found that T. denticola preferentially binds FH and not FHL-1, and that FH is then cleaved by dentilisin to yield an FH subfragment of approximately 50 kDa. FH bound to dentilisin-deficient mutants but was not cleaved and retained its ability to serve as a cofactor for factor I in the cleavage of C3b. To assess the molecular basis of the interaction of FhbB with FH, mutational analyses were conducted. Replacement of specific residues in widely separated domains of FhbB and disruption of a central alpha helix with coiled-coil formation probability attenuated or eliminated FH binding. The data presented here are the first to demonstrate the retention at the cell surface of a proteolytic cleavage product of FH. The precise role of this FH fragment in the host-pathogen interaction remains to be determined.

Anaplasma phagocytophilum PSGL-1-independent infection does not require Syk and leads to less efficient AnkA delivery.

Anaplasma phagocytophilum is an obligate intracellular bacterium that infects neutrophils to cause granulocytic anaplasmosis in humans and mammals. P-selectin glycoprotein ligand-1 (PSGL-1) and the tetrasaccharide sialyl Lewis x (sLe(x)), which caps the PSGL-1 N-terminus, are confirmed A. phagocytophilum receptors. A. phagocytophilum is capable of sLe(x)-modified PSGL-1-dependent and -independent infection. PSGL-1 N-terminus-mediated entry is dependent on spleen tyrosine kinase (Syk). Here, we determined that PSGL-1-independent entry does not alter bacterial replication and investigated whether it involves Syk using NCH-1A2, an enriched subpopulation of A. phagocytophilum NCH-1 obtained through cultivation in a sLe(x)-deficient HL-60 cell line, HL-60 A2. Pharmacological inhibition of Syk nearly abolishes NCH-1 infection, but does not alter NCH-1A2 invasion and only marginally reduces NCH-1A2 propagation. This phenomenon was confirmed by a competitive infection assay using PSGL-1-dependent and -independent A. phagocytophilum organisms transformed to express mCherry or green fluorescent protein respectively. We also assayed for delivery and tyrosine phosphorylation of the A. phagocytophilum effector, AnkA, following NCH-1or NCH-1A2 incubation with HL-60 or HL-60 A2 cells in the presence of PSGL-1 blocking antibody. PSGL-1 N-terminus recognition promotes optimal AnkA delivery while binding to sLe(x) or the unknown receptor is comparably less important for this process.

Racioethnic diversity in the dynamics of the vaginal microbiome during pregnancy.

The microbiome of the female reproductive tract has implications for women's reproductive health. We examined the vaginal microbiome in two cohorts of women who experienced normal term births: a cross-sectionally sampled cohort of 613 pregnant and 1,969 non-pregnant women, focusing on 300 pregnant and 300 non-pregnant women of African, Hispanic or European ancestry case-matched for race, gestational age and household income; and a longitudinally sampled cohort of 90 pregnant women of African or non-African ancestry. In these women, the vaginal microbiome shifted during pregnancy toward Lactobacillus-dominated profiles at the expense of taxa often associated with vaginal dysbiosis. The shifts occurred early in pregnancy, followed predictable patterns, were associated with simplification of the metabolic capacity of the microbiome and were significant only in women of African or Hispanic ancestry. Both genomic and environmental factors are likely contributors to these trends, with socioeconomic status as a likely environmental influence.

The vaginal microbiome and preterm birth.

The incidence of preterm birth exceeds 10% worldwide. There are significant disparities in the frequency of preterm birth among populations within countries, and women of African ancestry disproportionately bear the burden of risk in the United States. In the present study, we report a community resource that includes 'omics' data from approximately 12,000 samples as part of the integrative Human Microbiome Project. Longitudinal analyses of 16S ribosomal RNA, metagenomic, metatranscriptomic and cytokine profiles from 45 preterm and 90 term birth controls identified harbingers of preterm birth in this cohort of women predominantly of African ancestry. Women who delivered preterm exhibited significantly lower vaginal levels of Lactobacillus crispatus and higher levels of BVAB1, Sneathia amnii, TM7-H1, a group of Prevotella species and nine additional taxa. The first representative genomes of BVAB1 and TM7-H1 are described. Preterm-birth-associated taxa were correlated with proinflammatory cytokines in vaginal fluid. These findings highlight new opportunities for assessment of the risk of preterm birth.