Spatial and Temporal Resolution of Cyanobacterial Bloom Chemistry Reveals an Open-Ocean Trichodesmium thiebautii as a Talented Producer of Specialized Metabolites.

While the ecological role that Trichodesmium sp. play in nitrogen fixation has been widely studied, little information is available on potential specialized metabolites that are associated with blooms and standing stock Trichodesmium colonies. While a collection of biological material from a T. thiebautii bloom event from North Padre Island, Texas, in 2014 indicated that this species was a prolific producer of chlorinated specialized metabolites, additional spatial and temporal resolution was needed. We have completed these metabolite comparison studies, detailed in the current report, utilizing LC-MS/MS-based molecular networking to visualize and annotate the specialized metabolite composition of these Trichodesmium blooms and colonies in the Gulf of Mexico (GoM) and other waters. Our results showed that T. thiebautii blooms and colonies found in the GoM have a remarkably consistent specialized metabolome. Additionally, we isolated and characterized one new macrocyclic compound from T. thiebautii, trichothilone A (1), which was also detected in three independent cultures of T. erythraeum. Genome mining identified genes predicted to synthesize certain functional groups in the T. thiebautii metabolites. These results provoke intriguing questions of how these specialized metabolites affect Trichodesmium ecophysiology, symbioses with marine invertebrates, and niche development in the global oligotrophic ocean.

Evaluation of Discipline-Specific Outcomes Through a Multidisciplinary Team Clinic for Patients With Isolated Cleft Palate.

OBJECTIVE: To describe the incidence and timing of provider-specific interventions for children with isolated cleft palate. DESIGN: This was a retrospective cohort study involving review of medical records. SETTING: Multidisciplinary team care clinic at a tertiary academic children's hospital between January 2000 and July 2019. PATIENTS: Patients with isolated nonsyndromic cleft palate seen by an American Cleft Palate-Craniofacial Association-approved team; 138 children were included. MAIN OUTCOME MEASURES: Study outcomes included incidence of secondary velopharyngeal management, tympanostomy tube insertion, speech therapy, hearing loss, dental/orthodontic treatment, and psychology interventions. Provider-specific outcomes were calculated for patients at ages 0 to 3, 3 to 5, and >5 years. RESULTS: Median follow-up time was 7.0 years (interquartile range: 3.3-11.8 years). At their last team assessment, 42% of patients still had conductive hearing loss. The rate of tympanostomy tube insertions not done alongside a palatoplasty was highest for ages 3 to 5 and dropped after new American Academy of Otolaryngology-Head and Neck Surgery Foundation guidelines in 2013 (P = .015); 54% of patients received speech-language therapy during follow-up. Palatoplasty, psychology, and dental/orthodontic treatment were all less common than speech or ENT treatment (P < .01). Secondary palatoplasty was performed in 31 patients (22%). Patients who received speech, dental/orthodontic, or psychology intervention followed up longer than those who did not (9.8 vs 2.1 years, P < .001). CONCLUSION: Half of the patients terminated team follow-up by age 7, suggesting that burden of care outweighed perceived benefits of continued follow-up for many families. These results can be used to adjust protocols for children with isolated cleft palate.

Evaluation of Multidisciplinary Team Clinic for Patients With Isolated Cleft Lip.

OBJECTIVE: To report the incidences of secondary lip and nose operations, otolaryngology procedures, speech-language therapy, neurodevelopmental concerns, and dental and orthodontic issues in children with isolated cleft lip to inform multidisciplinary cleft team protocols. SETTING: An American Cleft Palate-Craniofacial Association-approved team at a tertiary academic children's hospital. DESIGN: Retrospective cohort study of patients evaluated through longitudinal clinic visits by a multidisciplinary cleft palate and craniofacial team between January 2000 and June 2018. PATIENTS, PARTICIPANTS: Children with nonsyndromic cleft lip with or without cleft alveolus (n = 92). RESULTS: Median age at final team visit was 4.9 years (interquartile range: 2.4-8.2 years). Secondary plastic surgery procedures were most common between ages 3 and 5 (135 per 1000 person-years), and the majority of these procedures were minor lip revisions. The rate of tympanostomy tube insertion was highest before age 3 (122 per 1000 person-years). By their final team visit, 88% of patients had normal hearing and 11% had only slight to mild conductive hearing loss. No patients had speech errors attributable to lip abnormalities. Psychological interventions, learning disabilities, and dental or orthodontic concerns were uncommon. CONCLUSIONS: Most patients with isolated cleft lip may not require long-term, longitudinal evaluation by cleft team specialists. Cleft teams should develop limited follow-up protocols for these children to improve resource allocation and promote value-based care in this patient population.

Renal Tumors of Childhood: Radiologic-Pathologic Correlation Part 2. The 2nd Decade: From the Radiologic Pathology Archives.

Malignant renal tumors account for 7% of childhood cancers, and Wilms tumors are by far the most common-but not in older children and adolescents. Among individuals in the latter half of their 2nd decade of life, renal cell carcinoma (RCC) is more common than Wilms tumor. The histopathologic spectrum of RCCs in children differs from that in adults. The most common subtype of RCC in children and adolescents is Xp11.2 translocation RCC, which is distinguished by hyperattenuation at nonenhanced computed tomography, a defined capsule, and associated retroperitoneal lymphadenopathy. Papillary RCC is the second most common histologic subtype. It enhances less intensely compared with the adjacent renal parenchyma and has a propensity for calcification. Clear cell RCC is seen in patients with von Hippel-Lindau disease and is distinguished by its relatively hypervascular nature. Medullary carcinoma affects adolescents with the sickle cell trait and is characterized by an infiltrative growth pattern and extensive metastasis at presentation. Angiomyolipoma is seen in children with tuberous sclerosis complex and is often multifocal and hypervascular, with macroscopic fat. Metanephric tumors are central, circumscribed, and typically calcified. Lymphoma usually manifests as multifocal masses, but it may involve a solitary mass or infiltrative pattern. Extensive adenopathy and involvement of the gastrointestinal tract or other organs also may be seen. Primitive neuroectodermal tumor is an aggressive neoplasm that is typically quite large at diagnosis. Knowledge of the clinical, biologic, and histopathologic features of renal tumors in older children and adolescents and their effects on the imaging appearance can help the radiologist offer a useful preoperative differential diagnosis.

Metabolic activity of the tongue in obstructive sleep apnea. A novel application of FDG positron emission tomography imaging.

RATIONALE: The metabolic activity of the tongue is unknown in patients with obstructive sleep apnea (OSA). Tongue electromyographic (EMG) activity is increased in patients with OSA. This increase in tongue EMG activity is thought to be related to either increased neuromuscular compensation or denervation with subsequent reinnervation of the muscle fibers. Increased glucose uptake in the tongue would support increased neuromuscular compensation, whereas decreased glucose uptake in the tongue would support denervation with subsequent reinnervation of the muscle fibers. OBJECTIVES: To investigate the metabolic activity of the genioglossus and control upper airway muscles in obese patients with sleep apnea compared with obese control subjects. METHODS: Obese subjects with and without OSA underwent a standard overnight sleep study to determine an apnea-hypopnea index. Each subject had a positron emission tomography with [(18)F]-2-fluoro-2-deoxy-D-glucose scan in addition to noncontrast computed tomography or magnetic resonance imaging. Glucose uptake was quantified within upper airway tissues with the standardized uptake value. MEASUREMENTS AND MAIN RESULTS: We recruited 30 obese control subjects (apnea-hypopnea index, 4.7 ± 3.1 events per hour) and 72 obese patients with sleep apnea (apnea-hypopnea index, 43.5 ± 28.0 events per hour). Independent of age, body mass index, sex, and race, patients with OSA had significantly reduced glucose uptake in the genioglossus (P = 0.03) in comparison with obese normal subjects. No differences in standardized uptake value were found in the control muscles (masseter [P = 0.38] and pterygoid [P = 0.70]) and subcutaneous fat deposits (neck [P = 0.44] and submental [P = 0.95]) between patients with OSA and control subjects. CONCLUSIONS: There was significantly reduced glucose uptake in the genioglossus of patients with sleep apnea in comparison with obese normal subjects with [(18)F]-2-fluoro-2-deoxy-D-glucose positron emission tomography imaging. The reduction in glucose uptake was likely secondary to alterations in tongue muscle fiber-type or secondary to chronic denervation. The reduced glucose uptake argues against the neuromuscular compensation hypothesis explaining the increase in tongue EMG activity in obese patients with OSA.

Temporal Dynamics of Cyanobacterial Bloom Community Composition and Toxin Production from Urban Lakes.

With a long evolutionary history and a need to adapt to a changing environment, cyanobacteria in freshwater systems use specialized metabolites for communication, defense, and physiological processes. However, the role that these metabolites play in differentiating species, maintaining microbial communities, and generating niche persistence and expansion is poorly understood. Furthermore, many cyanobacterial specialized metabolites and toxins present significant human health concerns due to their liver toxicity and their potential impact to drinking water. Gaps in knowledge exist with respect to changes in species diversity and toxin production during a cyanobacterial bloom (cyanoHAB) event; addressing these gaps will improve understanding of impacts to public and ecological health. In the current project, we utilized a multiomics strategy (DNA metabarcoding and metabolomics) to determine the cyanobacterial community composition, toxin profile, and the specialized metabolite pool at three freshwater lakes in Providence, RI during summer-fall cyanoHABs. Species diversity decreased at all study sites over the course of the bloom event, and toxin production reached a maximum at the midpoint of the event. Additionally, LC-MS/MS-based molecular networking identified new toxin congeners. This work provokes intriguing questions with respect to the use of allelopathy by organisms in these systems and the presence of emerging toxic compounds that can impact public health.

Simulated upwelling and marine heatwave events promote similar growth rates but differential domoic acid toxicity in Pseudo-nitzschia australis.

Along the west coast of the United States, highly toxic Pseudo-nitzschia blooms have been associated with two contrasting regional phenomena: seasonal upwelling and marine heatwaves. While upwelling delivers cool water rich in pCO2 and an abundance of macronutrients to the upper water column, marine heatwaves instead lead to warmer surface waters, low pCO2, and reduced nutrient availability. Understanding Pseudo-nitzschia dynamics under these two conditions is important for bloom forecasting and coastal management, yet the mechanisms driving toxic bloom formation during contrasting upwelling vs. heatwave conditions remain poorly understood. To gain a better understanding of what drives Pseudo-nitzschia australis growth and toxicity during these events, multiple-driver scenario or 'cluster' experiments were conducted using temperature, pCO2, and nutrient levels reflecting conditions during upwelling (13 °C, 900 ppm pCO2, replete nutrients) and two intensities of marine heatwaves (19 °C or 20.5 °C, 250 ppm pCO2, reduced macronutrients). While P. australis grew equally well under both heatwave and upwelling conditions, similar to what has been observed in the natural environment, cells were only toxic in the upwelling treatment. We also conducted single-driver experiments to gain a mechanistic understanding of which drivers most impact P. australis growth and toxicity. These experiments indicated that nitrogen concentration and N:P ratio were likely the drivers that most influenced domoic acid production, while the impacts of temperature or pCO2 concentration were less pronounced. Together, these experiments may help to provide both mechanistic and holistic perspectives on toxic P. australis blooms in the dynamic and changing coastal ocean, where cells interact simultaneously with multiple altered environmental variables.

Screening the PRISM Library against Staphylococcus aureus Reveals a Sesquiterpene Lactone from Liriodendron tulipifera with Inhibitory Activity.

Infections caused by the bacterium Staphylococcus aureus continue to pose threats to human health and put a financial burden on the healthcare system. The overuse of antibiotics has contributed to mutations leading to the emergence of methicillin-resistant S. aureus, and there is a critical need for the discovery and development of new antibiotics to evade drug-resistant bacteria. Medicinal plants have shown promise as sources of new small-molecule therapeutics with potential uses against pathogenic infections. The principal Rhode Island secondary metabolite (PRISM) library is a botanical extract library generated from specimens in the URI Youngken Medicinal Garden by upper-division undergraduate students. PRISM extracts were screened for activity against strains of methicillin-susceptible S. aureus (MSSA). An extract generated from the tulip tree (Liriodendron tulipifera) demonstrated growth inhibition against MSSA, and a bioassay-guided approach identified a sesquiterpene lactone, laurenobiolide, as the active constituent. Intriguingly, its isomers, tulipinolide and epi-tulipinolide, lacked potent activity against MSSA. Laurenobiolide also proved to be more potent against MSSA than the structurally similar sesquiterpene lactones, costunolide and dehydrocostus lactone. Laurenobiolide was the most abundant in the twig bark of the tulip tree, supporting the twig bark's historical and cultural usage in poultices and teas.

Self assembly of coiled-coil peptide-porphyrin complexes.

We are interested in the controlled assembly of photoelectronic materials using peptides as scaffolds and porphyrins as the conducting material. We describe the integration of a peptide-based polymer strategy with the ability of designed basic peptides to bind anionic porphyrins in order to create regulated photoelectronically active biomaterials. We have described our peptide system in earlier work, which demonstrates the ability of a peptide to form filamentous materials made up of self-assembling coiled-coil structures. We have modified this peptide system to include lysine residues appropriately positioned to specifically bind meso-tetrakis(4-sulfonatophenyl)porphine (TPPS(4)), a porphyrin that contains four negatively charged sulfonate groups at neutral pH. We measure the binding of TPPS(4) to our peptide using UV--visible and fluorescence spectroscopies to follow the porphyrin signature. We determine the concomitant acquisition of helical secondary structure in the peptide upon TPPS(4) binding using circular dichroism spectropolarimetry. This binding fosters polymerization of the peptide, as shown by absorbance extinction effects in the peptide CD spectra. The morphologies of the peptide/porphyrin complexes, as imaged by atomic force microscopy, are consistent with the coiled-coil polymers that we had characterized earlier, except that the heights are slightly higher, consistent with porphyrin binding. Evidence for exciton coupling in the copolymers is shown by red-shifting in the UV--visible data, however, the coupling is weak based on a lack of fluorescence quenching in fluorescence experiments.

Imaging of Combat-Related Thoracic Trauma - Review of Penetrating Trauma.

Introduction: Combat-related thoracic trauma is a significant contributor to morbidity and mortality of the casualties from Operation Enduring Freedom (OEF) and Operation Iraqi Freedom (OIF). Penetrating, blunt, and blast injuries were the most common mechanisms of trauma. Imaging plays a key role in the management of combat-related thoracic trauma casualties. This review discusses the imaging manifestations of thoracic injuries from penetrating trauma, emphasizing epidemiology and diagnostic clues seen during OEF and OIF. Materials and Methods: The assessment of radiologic findings in patients who suffer from combat-related thoracic trauma is the basis of this review article. The imaging modalities for this study include multi-detector computed tomography and chest radiography. Results: High-velocity penetrating projectile injuries appear as hemorrhage and re-expansion pulmonary edema from the temporary cavity and a linear, blood-filled track from the permanent cavity. In cases where the projectile passes totally through the body, entrance wounds at the skin surface and tracks through the subcutaneous tissues may be the only indications of penetrating trauma. When assessing vascular injury, special attention should be paid to the right hilum in contrast-enhanced multi-detector computed tomography, as contrast is concentrated in the superior vena cava and superior cavoatrial junction may obscure small fragments. Additionally, CT angiography may show vessel disruption or extravasation of contrast distal to normal vessel location in addition to intraluminal filling defects and pseudo-aneurysms. Tension pneumopericardium may rarely complicate penetrating or blunt chest trauma. On imaging, distension of the pericardial sack by pneumopericardium and compression of the heart support the diagnosis of tension. On multi-detector computed tomography in the acute trauma setting, fluid in the pleural space should be considered hemothorax, particularly when Hounsfield units are above 35. Acutely, extravasated blood will have similar attenuation to the thoracic vasculature, whereas clotted blood will have higher values of 50-90 Hounsfield units. Conclusion: Combat-related thoracic trauma continues to be a significant contributor to the morbidity and mortality of those injured during OEF and OIF. This review of the imaging manifestations of penetrating thoracic injury during OEF and OIF focuses on key diagnostic findings for clinicians caring for combat casualties. The distinct injury pattern and atypical imaging manifestations of penetrating trauma are important to recognize early due to the acuity of this patient population and the influence of accurate diagnosis on clinical management.

Imaging of Combat-Related Thoracic Trauma - Blunt Trauma and Blast Lung Injury.

Introduction: Combat-related thoracic trauma (CRTT) is a significant contributor to morbidity and mortality of the casualties from Operation Enduring Freedom (OEF) and Operation Iraqi Freedom (OIF). Penetrating, blunt, and blast injuries are the most common mechanisms of trauma to the chest. Imaging plays a key role in the battlefield management of CRTT casualties. This work discusses the imaging manifestations of thoracic injuries from blunt trauma and blast injury, emphasizing epidemiology and diagnostic clues seen during OEF and OIF. Materials and Methods: The assessment of radiologic findings in patients who suffer from combat-related blunt thoracic trauma and blast injury is the basis of this work. The imaging modalities for this work include multi-detector computed tomography (MDCT) and chest radiography. Results: Multiple imaging modalities are available to imagers on or near the battlefront, including radiography, fluoroscopy, and MDCT. MDCT with multi-planar reconstructions is the most sensitive imaging modality available in combat hospitals for the evaluation of CRTT. In modern combat, blunt and blast injuries account for a significant portion of CRTT. Individual body armor converts penetrating trauma to blunt trauma, leading to pulmonary contusion that accounted for 50.2% of thoracic injuries during OIF and OEF. Flail chest, a subset of blunt chest injury, is caused by significant blunt force to the chest and occurs four times as frequently in combat casualties when compared with the civilian population. Imaging features of CRTT have significant diagnostic and prognostic value. Pulmonary contusions on chest radiography appear as patchy consolidations in the acute setting with ill-defined and non-segmental borders. MDCT of the chest is a superior imaging modality in diagnosing and evaluating pulmonary contusion. Contusions on MDCT appear as crescentic ground-glass opacities (opacities through which lung interstitium and vasculature are still visible) and areas of consolidation that often do not respect the anatomic boundaries of the affected lobes. Additionally, small pulmonary contusions may exhibit sub-pleural sparing and may distinguish contusion from pneumonia or other lung pathology. Although pulmonary laceration is typically the result of penetrating trauma, laceration may also be caused by displaced rib fractures or significant shearing forces on the lung without penetrating injury. Because of elastic recoil of the normal pulmonary parenchyma surrounding the injury, pulmonary lacerations may present as late as 48-72 h after injury. Pulmonary lacerations may appear similar to pulmonary contusions on chest radiography initially and will require MDCT for definitive diagnosis. Blast injury is a defining injury of modern combat. Blast lung injury is initially diagnosed with chest radiography, where the pattern of lung opacities has previously been described by clinicians as "batwing" or "butterfly" because of its central appearance in the lung. "Peribronchovascular" may be a more accurate description of primary blast lung based on its appearance on MDCT. This pattern may differentiate primary blast lung injury from other causes of thoracic trauma. Conclusion: CRTT continues to be a significant contributor to the morbidity and mortality of those injured during OEF and OIF. The distinct injury patterns and atypical imaging manifestations of blunt trauma and blast lung injury are important to recognize early because of the acuity of this patient population and the influence of accurate diagnosis on clinical management.

Imaging in Congenital and Hereditary Abnormalities of the Interventricular Septum: Clinical Anatomy and Diagnostic Clues.

Early identification of congenital heart diseases, specifically those affecting the structural integrity and function of the interventricular septum, in childhood is important toward decreasing the morbidity and mortality of those affected. We review the pertinent clinical and imaging manifestations for those with ventricular septal defects, ventricular septal aneurysms, tetralogy of Fallot, and hypertrophic (obstructive) cardiomyopathy, in addition to discussing first-line imaging studies, including echocardiography, and indications for advanced imaging.

Tongue fat and its relationship to obstructive sleep apnea.

STUDY OBJECTIVES: The objective of this study was to determine whether tongue fat is increased in obese sleep apneics compared to obese subjects without sleep apnea. We hypothesized that excess fat is deposited in the tongue in obese patients with sleep apnea. DESIGN: Case-control design. SETTING: Academic medical center. PATIENTS: We examined tongue fat in 31 obese controls (apnea-hypopnea index, 4.1 ± 2.7 events/h) and 90 obese apneics (apnea-hypopnea index, 43.2 ± 27.3 events/h). Analyses were repeated in a subsample of 18 gender-, race-, age-, and BMI-matched case-control pairs. INTERVENTIONS: All subjects underwent a MRI with three-point Dixon magnetic resonance imaging. We used sophisticated volumetric reconstruction algorithms to study the size and distribution of upper airway fat deposits in the tongue and masseter muscles within apneics and obese controls. MEASUREMENTS AND RESULTS: The data supported our a priori hypotheses that after adjustment for age, BMI, gender, and race, the tongue in apneics was significantly larger (P = 0.001) and had an increased amount of fat (P = 0.002) compared to controls. Similar results were seen in our matched sample. Our data also demonstrate that within the apneic and normal tongue, there are regional differences in fat distribution, with larger fat deposits at the base of the tongue. CONCLUSIONS: There is increased tongue volume and deposition of fat at the base of tongue in apneics compared to controls. Increased tongue fat may begin to explain the relationship between obesity and obstructive sleep apnea.