7 research outputs found
On stars and spikes: Resolving the skeletal morphology of planktonic Acantharia using synchrotron X-ray nanotomography and deep learning image segmentation
Acantharia (Acantharea) are wide-spread marine protozoa, presenting one of the rare examples of strontium sulfate mineralization in the biosphere. Their endoskeletons consist of 20 spicules arranged according to a unique geometric pattern named Müller's principle. Given the diverse mineral architecture of the Acantharia class, we set out to examine the complex three-dimensional skeletal morphology at the nanometer scale using synchrotron X-ray nanotomography, followed by image segmentation based on deep learning methods. The present study focuses on how the spicules emanate from the robust central junction in the orders Symphyacanthida and Arthracanthida, the geometry of lateral spicule wings as well as pockets of interspicular space, which may be involved in cell compartmentalization. Through these morphometric studies, we observed subtle deviations from the previously described spatial arrangement of the spicules. According to our data, spicule shapes are adjusted in opposite spicules as to accommodate the overall spicule arrangement. In all types examined, previously unknown interspicular interstices were found in areas where radial spicules meet, which could have implications for the crystal growth mechanism and overall endoskeletal integrity. A deeper understanding of the spiculogenesis in Acantharia can provide biomimetic routes towards complex inorganic shapes
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Treatment of Anal High-Grade Squamous Intraepithelial Lesions to Prevent Anal Cancer
BACKGROUND: The incidence of anal cancer is substantially higher among persons living with the human immunodeficiency virus (HIV) than in the general population. Similar to cervical cancer, anal cancer is preceded by high-grade squamous intraepithelial lesions (HSILs). Treatment for cervical HSIL reduces progression to cervical cancer; however, data from prospective studies of treatment for anal HSIL to prevent anal cancer are lacking. METHODS: We conducted a phase 3 trial at 25 U.S. sites. Persons living with HIV who were 35 years of age or older and who had biopsy-proven anal HSIL were randomly assigned, in a 1:1 ratio, to receive either HSIL treatment or active monitoring without treatment. Treatment included office-based ablative procedures, ablation or excision under anesthesia, or the administration of topical fluorouracil or imiquimod. The primary outcome was progression to anal cancer in a time-to-event analysis. Participants in the treatment group were treated until HSIL was completely resolved. All the participants underwent high-resolution anoscopy at least every 6 months; biopsy was also performed for suspected ongoing HSIL in the treatment group, annually in the active-monitoring group, or any time there was concern for cancer. RESULTS: Of 4459 participants who underwent randomization, 4446 (99.7%) were included in the analysis of the time to progression to cancer. With a median follow-up of 25.8 months, 9 cases were diagnosed in the treatment group (173 per 100,000 person-years; 95% confidence interval [CI], 90 to 332) and 21 cases in the active-monitoring group (402 per 100,000 person-years; 95% CI, 262 to 616). The rate of progression to anal cancer was lower in the treatment group than in the active-monitoring group by 57% (95% CI, 6 to 80; P = 0.03 by log-rank test). CONCLUSIONS: Among participants with biopsy-proven anal HSIL, the risk of anal cancer was significantly lower with treatment for anal HSIL than with active monitoring. (Funded by the National Cancer Institute; ClinicalTrials.gov number, NCT02135419.)
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Treatment of Anal High-Grade Squamous Intraepithelial Lesions to Prevent Anal Cancer
Like cervical cancer, anal cancer is often caused by a human papillomavirus and has a premalignant stage called high-grade squamous intraepithelial lesion or anal intraepithelial neoplasia. A randomized trial showed that treating HSIL led to a 57% reduction in progression to anal cancer as compared with active surveillance
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Treatment of Anal High-Grade Squamous Intraepithelial Lesions to Prevent Anal Cancer
BackgroundThe incidence of anal cancer is substantially higher among persons living with the human immunodeficiency virus (HIV) than in the general population. Similar to cervical cancer, anal cancer is preceded by high-grade squamous intraepithelial lesions (HSILs). Treatment for cervical HSIL reduces progression to cervical cancer; however, data from prospective studies of treatment for anal HSIL to prevent anal cancer are lacking.MethodsWe conducted a phase 3 trial at 25 U.S. sites. Persons living with HIV who were 35 years of age or older and who had biopsy-proven anal HSIL were randomly assigned, in a 1:1 ratio, to receive either HSIL treatment or active monitoring without treatment. Treatment included office-based ablative procedures, ablation or excision under anesthesia, or the administration of topical fluorouracil or imiquimod. The primary outcome was progression to anal cancer in a time-to-event analysis. Participants in the treatment group were treated until HSIL was completely resolved. All the participants underwent high-resolution anoscopy at least every 6 months; biopsy was also performed for suspected ongoing HSIL in the treatment group, annually in the active-monitoring group, or any time there was concern for cancer.ResultsOf 4459 participants who underwent randomization, 4446 (99.7%) were included in the analysis of the time to progression to cancer. With a median follow-up of 25.8 months, 9 cases were diagnosed in the treatment group (173 per 100,000 person-years; 95% confidence interval [CI], 90 to 332) and 21 cases in the active-monitoring group (402 per 100,000 person-years; 95% CI, 262 to 616). The rate of progression to anal cancer was lower in the treatment group than in the active-monitoring group by 57% (95% CI, 6 to 80; P = 0.03 by log-rank test).ConclusionsAmong participants with biopsy-proven anal HSIL, the risk of anal cancer was significantly lower with treatment for anal HSIL than with active monitoring. (Funded by the National Cancer Institute; ClinicalTrials.gov number, NCT02135419.)
Intubation Practices and Adverse Peri-intubation Events in Critically Ill Patients from 29 Countries
Importance: Tracheal intubation is one of the most commonly performed and high-risk interventions in critically ill patients. Limited information is available on adverse peri-intubation events. Objective: To evaluate the incidence and nature of adverse peri-intubation events and to assess current practice of intubation in critically ill patients. Design, Setting, and Participants: The International Observational Study to Understand the Impact and Best Practices of Airway Management in Critically Ill Patients (INTUBE) study was an international, multicenter, prospective cohort study involving consecutive critically ill patients undergoing tracheal intubation in the intensive care units (ICUs), emergency departments, and wards, from October 1, 2018, to July 31, 2019 (August 28, 2019, was the final follow-up) in a convenience sample of 197 sites from 29 countries across 5 continents. Exposures: Tracheal intubation. Main Outcomes and Measures: The primary outcome was the incidence of major adverse peri-intubation events defined as at least 1 of the following events occurring within 30 minutes from the start of the intubation procedure: cardiovascular instability (either: systolic pressure <65 mm Hg at least once, <90 mm Hg for >30 minutes, new or increase need of vasopressors or fluid bolus >15 mL/kg), severe hypoxemia (peripheral oxygen saturation <80%) or cardiac arrest. The secondary outcomes included intensive care unit mortality. Results: Of 3659 patients screened, 2964 (median age, 63 years; interquartile range [IQR], 49-74 years; 62.6% men) from 197 sites across 5 continents were included. The main reason for intubation was respiratory failure in 52.3% of patients, followed by neurological impairment in 30.5%, and cardiovascular instability in 9.4%. Primary outcome data were available for all patients. Among the study patients, 45.2% experienced at least 1 major adverse peri-intubation event. The predominant event was cardiovascular instability, observed in 42.6% of all patients undergoing emergency intubation, followed by severe hypoxemia (9.3%) and cardiac arrest (3.1%). Overall ICU mortality was 32.8%. Conclusions and Relevance: In this observational study of intubation practices in critically ill patients from a convenience sample of 197 sites across 29 countries, major adverse peri-intubation events - in particular cardiovascular instability - were observed frequently
Evolution over Time of Ventilatory Management and Outcome of Patients with Neurologic Disease∗
OBJECTIVES: To describe the changes in ventilator management over time in patients with neurologic disease at ICU admission and to estimate factors associated with 28-day hospital mortality. DESIGN: Secondary analysis of three prospective, observational, multicenter studies. SETTING: Cohort studies conducted in 2004, 2010, and 2016. PATIENTS: Adult patients who received mechanical ventilation for more than 12 hours. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Among the 20,929 patients enrolled, we included 4,152 (20%) mechanically ventilated patients due to different neurologic diseases. Hemorrhagic stroke and brain trauma were the most common pathologies associated with the need for mechanical ventilation. Although volume-cycled ventilation remained the preferred ventilation mode, there was a significant (p < 0.001) increment in the use of pressure support ventilation. The proportion of patients receiving a protective lung ventilation strategy was increased over time: 47% in 2004, 63% in 2010, and 65% in 2016 (p < 0.001), as well as the duration of protective ventilation strategies: 406 days per 1,000 mechanical ventilation days in 2004, 523 days per 1,000 mechanical ventilation days in 2010, and 585 days per 1,000 mechanical ventilation days in 2016 (p < 0.001). There were no differences in the length of stay in the ICU, mortality in the ICU, and mortality in hospital from 2004 to 2016. Independent risk factors for 28-day mortality were age greater than 75 years, Simplified Acute Physiology Score II greater than 50, the occurrence of organ dysfunction within first 48 hours after brain injury, and specific neurologic diseases such as hemorrhagic stroke, ischemic stroke, and brain trauma. CONCLUSIONS: More lung-protective ventilatory strategies have been implemented over years in neurologic patients with no effect on pulmonary complications or on survival. We found several prognostic factors on mortality such as advanced age, the severity of the disease, organ dysfunctions, and the etiology of neurologic disease