Ambulatory 7-day mechanical circulatory support in sheep model of pulmonary hypertension and right heart failure.

BACKGROUND: Right heart failure is the major cause of death in pulmonary hypertension. Lung transplantation is the only long-term treatment option for patients who fail medical therapy. Due to the scarcity of donor lungs, there is a critical need to develop durable mechanical support for the failing right heart. A major design goal for durable support is to reduce the size and complexity of devices to facilitate ambulation. Toward this end, we sought to deploy wearable mechanical support technology in a sheep disease model of chronic right heart failure. METHODS: In 6 sheep with chronic right heart failure, a mechanical support system consisting of an extracorporeal blood pump coupled with a gas exchange unit was attached in a right atrium-to-left atrium configuration for up to 7 days. Circuit performance, hematologic parameters, and animal hemodynamics were analyzed. RESULTS: Six subjects underwent the chronic disease model for 56 to 71 days. Three of the subjects survived to the 7-day end-point for circulatory support. The circuit provided 2.8 (0.5) liter/min of flow compared to the native pulmonary blood flow of 3.5 (1.1) liter/min. The animals maintained physiologically balanced blood gas profile with a sweep flow of 1.2 (1.0) liter/min. Two animals freely ambulated while wearing the circuit. CONCLUSIONS: Our novel mechanical support system provided physiologic support for a large animal model of pulmonary hypertension with right heart failure. The small footprint of the circuit and the low sweep requirement demonstrate the feasibility of this technology to enable mobile ambulatory applications.

A Comparison of Study Behaviors and Metacognitive Evaluation Used by Biology Students.

Student-study behaviors and metacognition are predictors of student-academic success. However, student metacognitive evaluation of their own study habit behavior use has been largely unexplored. To address this gap, we gave students enrolled in three different Biology courses (n = 1140) a survey that asked them to identify the study behaviors used to prepare for their first and third exams and to appraise the effectiveness of each behavior. We observed that, across all courses, students used different counts of active- and passive-study behaviors. However, there were no differences in performance across courses, and the use of effective (i.e., active) study behaviors resulted in improved exam performance for all students, regardless of course, while the use of ineffective (i.e., passive) study behaviors had no significant impact on exam performance. Finally, our qualitative analysis revealed that students across all courses demonstrated similar ability in identifying effective-study behaviors, but students could not explain why those behaviors were effective. Taken together, our study demonstrates that students use various study behaviors to prepare for exams without understanding their effectiveness. We encourage instructors to structure their courses to promote the development of metacognitive evaluation and effective-study behaviors.

Xenogeneic cross-circulation for physiological support and recovery of ex vivo human livers.

BACKGROUND AND AIMS: The scarcity of suitable donor livers highlights a continuing need for innovation to recover organs with reversible injuries in liver transplantation. APPROACH AND RESULTS: Explanted human donor livers (n = 5) declined for transplantation were supported using xenogeneic cross-circulation of whole blood between livers and xeno-support swine. Livers and swine were assessed over 24 hours of xeno-support. Livers maintained normal global appearance, uniform perfusion, and preservation of histologic and subcellular architecture. Oxygen consumption increased by 75% ( p = 0.16). Lactate clearance increased from -0.4 ± 15.5% to 31.4 ± 19.0% ( p = 0.02). Blinded histopathologic assessment demonstrated improved injury scores at 24 hours compared with 12 hours. Vascular integrity and vasoconstrictive function were preserved. Bile volume and cholangiocellular viability markers improved for all livers. Biliary structural integrity was maintained. CONCLUSIONS: Xenogeneic cross-circulation provided multisystem physiological regulation of ex vivo human livers that enabled functional rehabilitation, histopathologic recovery, and improvement of viability markers. We envision xenogeneic cross-circulation as a complementary technique to other organ-preservation technologies in the recovery of marginal donor livers or as a research tool in the development of advanced bioengineering and pharmacologic strategies for organ recovery and rehabilitation.

Five new species in the predaceous midge genus Macrurohelea Ingram amp; Macfie from Argentina, and descriptions of the previously unknown males of M. kuscheli Wirth and M. monotheca Spinelli amp; Grogan (Diptera: Ceratopogonidae).

Five new Neotropical species in the predaceous midge genus Macrurohelea Ingram Macfie are described: M. bassoi, M. donatoi, M. morenoi, M. sirii, and M. ventanensis, n. spp. and the previously unknown males of M. kuscheli Wirth and M. monotheca Spinelli Grogan are described from specimens collected in several localities of Argentina and Chile. Illustrations and photomicrographs of key features of both sexes are provided as well as a key to all Neotropical species of Macrurohelea.

Extracorporeal membrane oxygenation in patients with hepatopulmonary syndrome undergoing liver transplantation: A systematic review of the literature.

BACKGROUND: Isolated cases of extracorporeal membrane oxygenation (ECMO) in patients with hepatopulmonary syndrome (HPS) undergoing liver transplantation (LT) have been reported with increasing frequency. We aimed to systemically review and synthesize the available literature on ECMO use in this population. METHODS: A systematic literature review of the PubMed, Web of Science, Cochrane Library, and Embase databases (end-of-search date: November 14, 2021) was conducted in accordance with the PRISMA statement. Eligible studies presented clinical parameters and outcomes of adult or pediatric patients with HPS receiving ECMO support at the time of, or following, LT. RESULTS: Sixteen studies from 4 continents reporting on 17 patients who were initiated on ECMO prior to (n = 2), during (n = 1) or after LT (n = 14) were included. Nine of the 16 studies were published between 2019 and 2021. The median pre-LT PaO2 was 38.0 mmHg (IQR 35.0-52.0). The median time from LT to ECMO initiation was 7 days (IQR, 3-12). Six patients (50%, n = 6 of 12) were extubated post-LT, before deterioration, development of refractory hypoxemia, and initiation of ECMO. Most patients were cannulated with a venovenous configuration (75%, n = 12 of 16). Most patients cannulated with a venoarterial or veno-arterial-venous strategy (75%, n = 3 of 4) had concurrent hemodynamic instability. The median total time on ECMO was 13 days (IQR 10-29). Using linear regression, for patients cannulated postoperatively, each day between LT and ECMO initiation was associated with a 3.5-day increase in total ECMO duration (95%CI: 2.23-4.73, p < 0.001, R2 = 73.7%). The median postoperative intensive care unit length of stay was 40 days (IQR, 37-61) and hospital length of stay was 59.5 days (IQR 42-77). 82.4% of patients (14 of 17) survived to discharge. CONCLUSIONS: ECMO is feasible in patients with HPS undergoing LT and appears to be associated with better outcomes compared to other causes of cardiopulmonary failure in LT patients. As the volume of experience grows, ECMO may become a central part of perioperative support in LT patients with severe HPS.

A new species of predaceous midge in the genus Stilobezzia Kieffer from Mexico (Diptera: Ceratopogonidae).

The predaceous midges (Diptera: Ceratopogonidae; tribe Ceratopogonini) in the genera Schizonyxhelea Clastrier Stilobezzia Kieffer in Mexico were recently addressed by Huerta Grogan (2017) who described one new species in each of these genera. A re-examination of specimens in the Colección de Artrópodos con Importancia Medica (CAIM), from the states of Morelos and Yucatan, revealed an undescribed species that was previously identified as Stilobezzia (Stilobezzia) femoralis Lane Forattini from Yucatan by Huerta (2002) and Huerta Grogan (2017). Herein, we describe and illustrate this species from the states of Morelos Yucatan, Mexico, as Stilobezzia (Stilobezzia) tobiasi Huerta Grogan n. sp.

A Revision of the Nearctic Predaceous Midges in the Bezzia (Bezzia) pulverea complex (Diptera: Ceratopogonidae).

This revision of the Nearctic predaceous midges in the Bezzia (Bezzia) pulverea complex (Diptera: Ceratopogonidae) recognizes 11 species, seven of which are new species: Bezzia (B.) amblystyla, n. sp., from Maryland and Florida; B. (B.) brunneipedia, n. sp., from Florida; B. (B.) folkersti n. sp., from Florida; B. (B.) huberti, n. sp., from Maryland, Florida, Arkansas and Louisiana; B. (B.) leptostyla, n. sp., from Florida; B. (B.) marylandensis, n. sp., from Maryland; and, B. (B.) titanochela, n. sp., from Texas, Alabama and Florida. Photomicrographs of diagnostic characters of both sexes are included, and a key is provided to adult males and females of species in the Bezzia (B.) pulverea complex. Bezzia (B.) imbifida Dow Turner is transferred from the B. pulverea complex to the Bezzia (B.) expolita complex.

The Biting Midges of the Caribbean island Curaçao (Diptera: Ceratopogonidae). I. Species in the genus Dasyhelea Kieffer.

We document the first records of biting midges in the genus Dasyhelea Kieffer (Diptera: Ceratopogonidae) from Curaçao: Dasyhelea azteca Huerta & Grogan, D. bahamensis (Johnson), D. cincta (Coquillett), D. corinneae Gosseries, D. flavifrons (Guérin-Méneville) and D. grisea (Coquillett). The following six new species of Dasyhelea are described from this Caribbean island and their key features are presented in color photographs and illustrations: D. aliciae n. sp., D. recurva n. sp., D. latiala n. sp., D. rhopaloparamera n. sp., D. cyrtostyla n. sp., and D. curacaoensis n. sp. We also provide a key to males and females of all known species of Dasyhelea from Curaçao.

Multicenter, randomized, double-blind phase 2 trial of FOLFIRI with regorafenib or placebo as second-line therapy for metastatic colorectal cancer.

BACKGROUND: Regorafenib, a multikinase inhibitor that inhibits angiogenesis, growth, and proliferation, prolongs survival as monotherapy in patients with refractory colorectal cancer. This international, double-blind, placebo-controlled, multicenter trial assessed the efficacy of regorafenib with folinic acid, fluorouracil, and irinotecan (FOLFIRI) as a second-line treatment for metastatic colorectal cancer. METHODS: Patients with metastatic colorectal cancer who progressed on first-line oxaliplatin and fluoropyrimidine enrolled at 45 sites in the United States and Ireland. Patients, stratified by prior bevacizumab use, were randomized 2:1 to regorafenib or placebo. The treatment consisted of FOLFIRI on days 1 and 2 and days 15 and 16 with 160 mg of regorafenib or placebo on days 4 to 10 and days 18 to 24 of every 28-day cycle. Crossover was not allowed. The primary endpoint was progression-free survival (PFS). Under the assumption of a 75% event rate, 180 patients were required for 135 events to achieve 90% power to detect a hazard ratio (HR) of 0.65 with a 1-sided α value of .1. RESULTS: One hundred eighty-one patients were randomized (120 to regorafenib-FOLFIRI and 61 to placebo-FOLFIRI) with a median age of 62 years. Among these, 117 (65%) received prior bevacizumab or aflibercept. PFS was longer with regorafenib-FOLFIRI than placebo-FOLFIRI (median, 6.1 vs 5.3 months; HR, 0.73; 95% confidence interval [CI], 0.53-1.01; log-rank P = .056). The median overall survival was not longer (HR, 1.01; 95% CI, 0.71-1.44). The response rate was higher with regorafenib-FOLFIRI (34%; 95% CI, 25%-44%) than placebo-FOLFIRI (21%; 95% CI, 11%-33%; P = .07). Grade 3/4 adverse events with a >5% absolute increase from regorafenib included diarrhea, neutropenia, febrile neutropenia, hypophosphatemia, and hypertension. CONCLUSIONS: The addition of regorafenib to FOLFIRI as second-line therapy for metastatic colorectal cancer only modestly prolonged PFS over FOLFIRI alone. Cancer 2018. © 2018 American Cancer Society.

Biting midges of the genus Culicoides in South Carolina zoos.

Biting midges of the genus Culicoides (Diptera: Ceratopogonidae) were collected during the summer of 2007 at the Greenville and Riverbanks Zoos in South Carolina with Centers for Disease Control and Prevention (CDC) traps equipped with ultraviolet or incandescent lights and baited with carbon dioxide. Sixteen species of Culicoides were collected, four of which represented more than 80%. They were Culicoides guttipennis (Coquillett), Culicoides mulrenanni Beck, Culicoides obsoletus (Meigen), and Culicoides sanguisuga (Coquillett). C. guttipennis was found on a dead colobus monkey and a dead golden-headed lion tamarin; Culicoides husseyi Wirth & Blanton was collected from an unidentified, abandoned bird's nest. Ultraviolet light-equipped traps captured significantly more Culicoides specimens than traps with incandescent light. Half of the collected species previously have been associated with vertebrate pathogens, indicating a potential risk to captive animals.

Mosquitoes associated with US Department of Agriculture managed wetlands on Maryland's DelMarVa Peninsula.

Mosquito faunal studies were carried out 2004-2005 in Maryland's Eastern Shore wetlands managed by the US Department of Agriculture. The wetlands included flooded fields, inundated woodlands, and tidal salt marshes. Sampling methods included larval collections, adult landing counts, and CDC light and oviposition traps. A total of 1,186 larvae and 1,363 adults identified represented 14 species. Temporary pools were found to have the highest potential for rapid mosquito colonization with Psorophora columbiae the predominant species. Aedes vexans, Culex territans/pipiens, Ps. ciliata/howardii, and Anopheles crucians were collected primarily from pond and flooded woodlands. Ochlerotatus sollicitans larvae were sampled from tidal pools. The predominant daytime landing count species was Oc. sollicitans with Ps. ciliata, Ae. vexans, and Cx. territans also identified. Light traps collected An. crucians, the principal crepuscular species from flooded wooded areas. Aedes atlanticus, An. quadrimaculatus, Coquillettidia perturbans, Cx. restuans, Oc. sollicitans, Ps. ciliata, Ps. columbiae, and Uranotaenia sapphirina were also identified. Oviposition traps collected small numbers of An. crucians at the tidal marsh, 1 Ae. albopictus, and 1 each of Cx. territans/pipiens from the flooded woodlands. As a result of this study, it was recommended that abatement strategies be implemented during and after wetland construction to minimize the creation of temporary pool breeding sites.

Spiroplasma atrichopogonis sp. nov., from a ceratopogonid biting midge.

Spiroplasma sp. strain GNAT3597T was isolated from the biting midge genus Atrichopogon (Diptera: Ceratopogonidae). It was serologically distinct from other Spiroplasma species, groups or subgroups. Dark-field microscopy of the cells revealed the classical helical shape and subsequent transmission electron microscopy revealed cells surrounded by only a cell membrane (i.e. lacking a cell wall). Growth of strain GNAT3597T occurred in M1D medium at 30 degrees C. Strain GNAT3597T catabolized both glucose and arginine, but did not hydrolyse urea. The DNA G+C content of strain GNAT3597T was 29+/-1 mol%. Only one strain, SMCAT (Spiroplasma mirum), is serologically related to strain GNAT3597T, although the relationship is weak (positive reaction to only a 1 : 80 dilution). It is therefore proposed that strain GNAT3597T (=ATCC BAA-520T=NBRC 100390T) represents a novel species, Spiroplasma atrichopogonis sp. nov. (class Mollicutes: order Entomoplasmatales: family Spiroplasmataceae).