Pediatric Morgagni diaphragmatic hernia: a descriptive study.

INTRODUCTION: The Morgagni hernia (MH) accounts for 3-4% of congenital diaphragmatic hernias. There is a paucity of data regarding this rare defect. The purpose of this study is to describe the characteristics of children with MH, surgical approaches for repair, and patient outcomes. METHODS: Pediatric patients (ages 0-18) with a MH from 2002 to 2014 at a single, freestanding pediatric hospital were retrospectively reviewed. Patient presentation, demographics, operative methods and findings, and outcomes were evaluated. RESULTS: Twenty-six infants and children with a congenital MH were treated. There were 20 males (77%) and six females (23%) with a median age at diagnosis of 14.75 months (range 1 week to 13 years). Half were symptomatic. Sixteen hernias were repaired laparoscopically, nine by an open approach, and one laparoscopic converted to open. Colon was the most commonly herniated organ (N = 14). Hernia sacs were found in 22 patients of which, 20 were resected. Two patients underwent treatment with ECLS. There was one mortality in a patient who underwent repair on ECLS in the setting of an omphalocele and SVC obstruction. There were no recurrences in our sample. CONCLUSION: In this series, congenital MH appears to have a male predominance, frequently presents with pulmonary symptoms, and has excellent outcomes regardless of operative approach.

Transcriptomics in the tropics: Total RNA-based profiling of Costa Rican bromeliad-associated communities.

RNA-Seq was used to examine the microbial, eukaryotic, and viral communities in water catchments ('tanks') formed by tropical bromeliads from Costa Rica. In total, transcripts with taxonomic affiliation to a wide array of bacteria, archaea, and eukaryotes, were observed, as well as RNA-viruses that appeared related to the specific presence of eukaryotes. Bacteria from 25 phyla appeared to comprise the majority of transcripts in one tank (Wg24), compared to only 14 phyla in the other (Wg25). Conversely, eukaryotes from only 16 classes comprised the majority of transcripts in Wg24, compared to 24 classes in the Wg25, revealing a greater eukaryote diversity in the latter. Given that these bromeliads had tanks of similar size (i.e. vertical oxygen gradient), and were neighboring with presumed similar light regime and acquisition of leaf litter through-fall, it is possible that pH was the factor governing these differences in bacterial and eukaryotic communities (Wg24 had a tank pH of 3.6 and Wg25 had a tank pH of 6.2). Archaeal diversity was similar in both tanks, represented by 7 orders, with the exception of Methanocellales transcripts uniquely recovered from Wg25. Based on measures of FPKG (fragments mapped per kilobase of gene length), genes involved in methanogenesis, in addition to a spirochaete flagellin gene, were among those most highly expressed in Wg25. Conversely, aldehyde dehydrogenase and monosaccharide-binding protein were among genes most highly expressed in Wg24. The ability to observe specific presence of insect, plant, and fungi-associated RNA-viruses was unexpected. As with other techniques, there are inherent biases in the use of RNA-Seq, however, these data suggest the possibility of understanding the entire community, including ecological interactions, via simultaneous analysis of microbial, eukaryotic, and viral transcripts.

Bromeliad catchments as habitats for methanogenesis in tropical rainforest canopies.

Tropical epiphytic plants within the family Bromeliaceae are unusual in that they possess foliage capable of retaining water and impounded material. This creates an acidic (pH 3.5-6.5) and anaerobic (<1 ppm O(2)) environment suspended in the canopy. Results from a Costa Rican rainforest show that most bromeliads (n = 75/86) greater than ~20 cm in plant height or ~4-5 cm tank depth, showed presence of methanogens within the lower anoxic horizon of the tank. Archaea were dominated by methanogens (77-90% of recovered ribotypes) and community structure, although variable, was generally comprised of a single type, closely related to either hydrogenotrophic Methanoregula or Methanocella, a specific clade of aceticlastic Methanosaeta, or Methanosarcina. Juvenile bromeliads, or those species, such as Guzmania, with shallow tanks, generally did not possess methanogens, as assayed by polymerase chain reaction specific for methanogen 16S rRNA genes, nor did artificial catchments (~100 ml volume), in place 6-12 months prior to sample collection. Methanogens were not detected in soil (n = 20), except in one case, in which the dominant ribotype was different from nearby bromeliads. Recovery of methyl coenzyme M reductase genes supported the occurrence of hydrogenotrophic and aceticlastic methanogens within bromeliad tanks, as well as the trend, via QPCR analysis of mcrA, of increased methanogenic capacity with increased plant height. Methane production rates of up to 300 nmol CH(4) ml tank water(-1) day(-1) were measured in microcosm experiments. These results suggest that bromeliad-associated archaeal communities may play an important role in the cycling of carbon in neotropical forests.