Burden and Profile of Somatic Mutation in Duodenal Adenomas from Patients with Familial Adenomatous- and MUTYH-associated Polyposis

Purpose: Duodenal polyposis and cancer are important causes of morbidity and mortality in familial adenomatous polyposis (FAP) and MUTYH-associated polyposis (MAP). This study aimed to comprehensively characterize somatic genetic changes in FAP and MAP duodenal adenomas to better understand duodenal tumorigenesis in these disorders.Experimental Design: Sixty-nine adenomas were biopsied during endoscopy in 16 FAP and 10 MAP patients with duodenal polyposis. Ten FAP and 10 MAP adenomas and matched blood DNA samples were exome sequenced, 42 further adenomas underwent targeted sequencing, and 47 were studied by array comparative genomic hybridization. Findings in FAP and MAP duodenal adenomas were compared with each other and to the reported mutational landscape in FAP and MAP colorectal adenomas.Results: MAP duodenal adenomas had significantly more protein-changing somatic mutations (P = 0.018), truncating mutations (P = 0.006), and copy number variants (P = 0.005) than FAP duodenal adenomas, even though MAP patients had lower Spigelman stage duodenal polyposis. Fifteen genes were significantly recurrently mutated. Targeted sequencing of APC, KRAS, PTCHD2, and PLCL1 identified further mutations in each of these genes in additional duodenal adenomas. In contrast to MAP and FAP colorectal adenomas, neither exome nor targeted sequencing identified WTX mutations (P = 0.0017).Conclusions: The mutational landscapes in FAP and MAP duodenal adenomas overlapped with, but had significant differences to those reported in colorectal adenomas. The significantly higher burden of somatic mutations in MAP than FAP duodenal adenomas despite lower Spigelman stage disease could increase cancer risk in the context of apparently less severe benign disease. Clin Cancer Res; 23(21); 6721-32. ©2017 AACR.

Shift in species composition in the Anopheles gambiae complex after implementation of long-lasting insecticidal nets in Dielmo, Senegal

Long-lasting insecticidal nets (LLINs) and indoor residual spraying (IRS) are the cornerstones of malaria vector control. However, the effectiveness of these control tools depends on vector ecology and behaviour, which also largely determine the efficacy of certain Anopheles mosquitoes (Diptera: Culicidae) as vectors. Malaria vectors in sub-Saharan Africa are primarily species of the Anopheles gambiae complex, which present intraspecific differences in behaviour that affect how they respond to vector control tools. The focus of this study is the change in species composition in the An. gambiae complex after the implementation of LLINs in Dielmo, Senegal. The main findings referred to dramatic decreases in the proportions of Anopheles coluzzii and An. gambiae after the introduction of LLINs, and an increase in the proportion of Anopheles arabiensis. Two years after LLINs were first introduced, An. arabiensis remained the most prevalent species and An. gambiae had begun to rebound. This indicated a need to develop additional vector control tools that can target the full range of malaria vectors.

Nifedipine Induced Gingival Hyperplasia in Pregnancy: A Case Report

BACKGROUND

It is known that calcium channel blockers are associated with a risk of gingival hyperplasia. These drugs are widely used in the management of gestational hypertensive disorders.

CASE

A 27-year-old G1 woman presented with gingival hyperplasia at 27 weeks gestation during a hospitalisation for preeclampsia. She had been on nifedipine for hypertension for the last 9 weeks. Nifedipine was discontinued and replaced by methyldopa and already after 48 hours the gingival hyperplasia improved. She delivered two weeks later and the gingival hyperplasia resolved completely without surgical intervention. The Naranjo's score was used to prove the nifedipine's imputability.

CONCLUSION

This first case report of gingival hyperplasia induced by nifedipine in pregnancy could be used as a reference for clinicians in the management of this adverse effect during the pregnancy.

Comparing de novo and reference-based transcriptome assembly strategies by applying them to the blood-sucking bug Rhodnius prolixus

High Throughput Sequencing capabilities have made the process of assembling a transcriptome easier, whether or not there is a reference genome. But the quality of a transcriptome assembly must be good enough to capture the most comprehensive catalog of transcripts and their variations, and to carry out further experiments on transcriptomics. There is currently no consensus on which of the many sequencing technologies and assembly tools are the most effective. Many non-model organisms lack a reference genome to guide the transcriptome assembly. One question, therefore, is whether or not a reference-based genome assembly gives better results than de novo assembly. The blood-sucking insect Rhodnius prolixus-a vector for Chagas disease-has a reference genome. It is therefore a good model on which to compare reference-based and de novo transcriptome assemblies. In this study, we compared de novo and reference-based genome assembly strategies using three datasets (454, Illumina, 454 combined with Illumina) and various assembly software. We developed criteria to compare the resulting assemblies: the size distribution and number of transcripts, the proportion of potentially chimeric transcripts, how complete the assembly was (completeness evaluated both through CEGMA software and R. prolixus proteome fraction retrieved). Moreover, we looked for the presence of two chemosensory gene families (Odorant-Binding Proteins and Chemosensory Proteins) to validate the assembly quality. The reference-based assemblies after genome annotation were clearly better than those generated using de novo strategies alone. Reference-based strategies revealed new transcripts, including new isoforms unpredicted by automatic genome annotation. However, a combination of both de novo and reference-based strategies gave the best result, and allowed us to assemble fragmented transcripts.

De novo transcriptome assembly for a non-model species, the blood-sucking bug Triatoma brasiliensis, a vector of Chagas disease

High throughput sequencing (HTS) provides new research opportunities for work on non-model organisms, such as differential expression studies between populations exposed to different environmental conditions. However, such transcriptomic studies first require the production of a reference assembly. The choice of sampling procedure, sequencing strategy and assembly workflow is crucial. To develop a reliable reference transcriptome for Triatoma brasiliensis, the major Chagas disease vector in Northeastern Brazil, different de novo assembly protocols were generated using various datasets and software. Both 454 and Illumina sequencing technologies were applied on RNA extracted from antennae and mouthparts from single or pooled individuals. The 454 library yielded 278 Mb. Fifteen Illumina libraries were constructed and yielded nearly 360 million RNA-seq single reads and 46 million RNA-seq paired-end reads for nearly 45 Gb. For the 454 reads, we used three assemblers, Newbler, CAP3 and/or MIRA and for the Illumina reads, the Trinity assembler. Ten assembly workflows were compared using these programs separately or in combination. To compare the assemblies obtained, quantitative and qualitative criteria were used, including contig length, N50, contig number and the percentage of chimeric contigs. Completeness of the assemblies was estimated using the CEGMA pipeline. The best assembly (57,657 contigs, completeness of 80 %, <1 % chimeric contigs) was a hybrid assembly leading to recommend the use of (1) a single individual with large representation of biological tissues, (2) merging both long reads and short paired-end Illumina reads, (3) several assemblers in order to combine the specific advantages of each.

Formulation and stability study of a pediatric 2% phenylephrine hydrochloride eye drop solution

INTRODUCTION

We present formulation and stability evaluation of a 2% (w/v) phenylephrine hydrochloride biocompatible eye drop solution, routinely prepared in hospital pharmacy under aseptic conditions, for retinal examination of neonates and premature infants.

MATERIALS AND METHODS

Eye drop solution was formulated by dissolution of phenylephrine hydrochloride and disodium hydrogen phosphate as buffering agent in sterile water for injection and sodium chloride for injection as isotonic agent. The previous solution was sterile filtered through under aseptic conditions, in an iso class 5 air quality clean room under horizontal laminar airflow hood. Physical stability (visual inspection, osmolality measurements), chemical stability (pH measurement, phenylephrine assay by liquid chromatography coupled with an ultra-high resolution and accurate mass) and sterility evaluation of phenylephrine eye drop solution stored at ambient temperature were studied during 60 days.

RESULTS AND DISCUSSION

The formulated eye drop solution had a pH of 6.90±0.05 and an osmolality of 285±2 mOsm/kg. Throughout the 60 days study the solutions remained clear without any precipitation or color modification, sterility was maintained, pH and osmolality were not significantly modified and no significant loss of product was detected using liquid chromatography coupled with an ultra-high resolution and accurate mass instrument suggesting the lack of degradation.

CONCLUSION

These results indicate that 2% phenylephrine hydrochloride eye drop solutions were physically, chemically and microbiologically stable for at least 60 days when stored in type I amber glass vials at room temperature, allowing the compounding of higher batch sizes.

Open abdominal aortic aneurysm repair in the era of endovascular repair

OBJECTIVES

The development of minimally invasive techniques for abdominal aortic aneurysm (AAA) repair and the establishment of specialized centres have resulted in improved patient outcomes. This study examines open AAA repair at a non-specialized centre where advanced techniques are not practised.

METHODS

We conducted a retrospective analysis on a cohort of 83 patients presenting for AAA repair to a non-specialized hospital, the University Hospital of the West Indies (UHWI). The end points assessed included operative (30-day) mortality, postoperative complications, duration of operation, blood loss, intensive care unit (ICU) stay and overall hospital stay.

RESULTS

The overall operative mortality was 9.4% (23% for ruptured aneurysms and 5% for unruptured aneurysms). Mean operating time, blood loss, ICU stay and hospital stay were 326 +/- 98 minutes, 2420 +/- 1397 mls, 3 +/- 5 days and 9 +/- 5 days, respectively with no significant differences noted between ruptured and unruptured aneurysms. Mean aneurysm diameter was 6.13 +/- 1.59 cm.

CONCLUSION

Mortality rates for open aneurysm repair at the UHWI are consistent with findings in the current literature. Open AAA repair remains a safe treatment option in this environment. Continued improvements need to be made with respect to minimizing blood loss and operation duration, particularly in repairs of unruptured aneurysms.

New perspectives for population genetics of Chagas'disease vectors in the Northeastern Brazil: isolation of polymorphic microsatellite markers in Triatoma brasiliensis

Triatoma brasiliensis is the most important Chagas disease vector in semiarid areas of Northeastern Brazil. Although generally found in natural environment, it regularly colonizes or reinvades domiciliary ecotopes. In order to analyse gene flow between habitats, we identified and characterized six microsatellite loci using a microsatellite-enriched genomic library. To assess the usefulness of these microsatellites for genetic studies, we investigated their variability in two natural populations of the T. brasiliensis complex sampled in two Brazilian districts (Corone Jose Dia, South of Piaui state; Curaça, North of Bahia state). The taxonomic status of the samples was checked using cytb sequences. Phylogenetic analyses confirmed that the individuals from Bahia belonged to the T. juazeirensis species. Moreover, primers cross-amplification was tested in 5 Triatoma species and 4 loci successfully amplified in T. infestans and T. guasayana.

Microsatellite markers in Triatoma pseudomaculata (Hemiptera, Reduviidae, Triatominae), Chagas' disease vector in Brazil

Six polymorphic microsatellite loci were isolated and characterized using a microsatellite-enriched genomic library from the Chagas' disease vector Triatoma pseudomaculata. This species is found in Brasil in Caatinga areas and predominantly in peridomestic habitats. All the microsatellites tested on a population of T. pseudomaculata sampled in the Bahia State, Brazil, were polymorphic (2-15 alleles). Markers amplification was also tested on six Triatoma species and some loci successfully amplified in the most phylogenetically related species, in particular Triatoma brasiliensis.

Microsatellite markers from the Chagas disease vector, Rhodnius prolixus (Hemiptera, Reduviidae), and their applicability to Rhodnius species

Ten microsatellites were isolated and characterized from a partial genomic library of Rhodnius prolixus, the principal Chagas disease vector in Venezuela, Colombia and Central America. These polymorphic molecular markers could be particularly useful in Chagas disease control initiatives. A wider applicability of the primer-pairs isolated was shown, from 6 to 10 loci being amplifiable in five out of the ten Rhodnius species tested, namely R. domesticus, R. nasutus, R. neglectus, R. neivai and R. robustus. Interestingly, all the loci were amplified in the latter. These markers may be of interest to trace the colonization of human dwellings from triatomine sylvatic populations in order to better define epidemiological risk patterns.

Evolutionary novelties in islands: Drosophila santomea, a new melanogaster sister species from São Tomé

The finding of new melanogaster sister species may help us in understanding more about how the emergence of genetic novelties, particularly in insular habitats, can result in speciation. Here we report on the discovery of Drosophila santomea, which is the first melanogaster sibling found off West-equatorial Africa, on São Tomé, one of the Gulf of Guinea islands. Although the eight other melanogaster sister species are remarkably conservative in their morphology except for their terminalia, the new find has a morphological trait distinguishing it from all of these: a pure yellow body coloration of both sexes without the normal black abdominal banding. Evidence from the terminalia, polytene and mitotic chromosomes, period gene and allozymes are provided indicating that it is nonetheless the nearest relative of Drosophila yakuba with which it coexists on the island. The new find is a clear-cut taxon as shown by the production of sterile male hybrids, eventually with developmental defects, in both directions of cross with yakuba and by the existence of an altitudinal divide accompanied by a hybrid zone at mid-elevation on the island. Molecular and karyotypic data further support this conclusion. In contrast to the significant divergence of their nuclear DNAs, an intriguing similarity in their cytochrome b sequences was observed indicating a recent coalescence common to santomea, yakuba and also teissieri cytoplasms. These were shown to harbour the same Wolbachia endosymbiotic bacteria which could possibly be responsible for mitochondrial DNA hitchhiking across the species barrier.

Molecular evidence for parallel evolution of adaptive syndromes in fig-breeding Lissocephala (Drosophilidae)

Afrotropical Lissocephala (Drosophilidae) breed strictly in syconia (figs) of Ficus (Moraceae) and have accordingly evolved specific features including modified female and eggshell morphologies, ovipositing, larval foraging, and mating behaviors. These various traits may exist as two or three alternative states. Each species displays a specific suite of traits so closely coordinated with one another that alternative states of the overall suites of traits can be seen as "adaptive syndromes." Three clear-cut adaptive syndromes can be recognized while two taxonomic lineages (juncta and sanu species groups) are traditionally accepted on the basis of male terminalia. A crucial evolutionary question results from the consideration that ecological clusters and taxonomic groups have conflicting compositions: the three syndromes are found in the juncta group while two of them occur in the sanu group. To resolve this conflict, we present molecular data which provide a robust phylogeny: mitochondrial DNA (12S + 16S ribosomal DNA and cytochrome b) sequence data are in agreement with one another regardless of the algorithm used. All molecular data consistently support male terminalia dichotomy. Such a level of consistency unambiguously indicates that parallel evolution of adaptive syndromes occurred. Thus, homoplasy may affect morphological and behavioral traits concomitantly when these are involved in a network of functional relationships.

Morphometric variability in the Chagas' disease vector Rhodnius prolixus

Morphometric variability was studied in six domestic Venezuelan populations of the blood-sucking bug Rhodnius prolixus Stal 1897 (Reduviidae, Triatominae) and in a sylvatic population identified as R. robustus Larrousse 1927. Evidence is here provided by both uni- and multifactorial analyses of extensive variation of morphological traits between the R. prolixus populations studied. Regardless the geographic or climatic environmental factor tested, none can be retained in a selective model accounting for the morphological variability observed. Moreover, the results failed to support any correlation between the morphological Mahalanobis' distances and geographical distances. The genetic relationships between these populations inferred from the present data, are more consistent with some demic structure, resulting from random genetic drift by founder effects, than with any alternative population genetic model. It is noteworthy that the range of variation of these morphological traits in R. prolixus includes the putative R. robustus population. Therefore, the species-specific status of R. robustus, at the very least the local Trujillo population studied, is questioned. In addition, a preliminary multifactorial analysis bearing on the three other Rhodnius relatives, R. pictipes Stal 1872, R. nasutus Stal 1859 and R. neglectus Lent 1954, confirmed the marked morphological differentiation of R. pictipes from all other species and showed a clear morphological differentiation of R. nasutus and R. neglectus both from one another and from R. prolixus.

Use of the median process of the pygophore in the identification of Rhodnius nasutus, R. neglectus, R. prolixus and R. robustus (Hemiptera: Reduviidae)

The morphometrics of the median process of the male pygophore of four species of blood-sucking bugs (Rhodnius prolixus, R. robustus, R. nasutus and R. neglectus) were compared using one-way analysis of variance. Although there were no significant differences in the pygophoral patterns within the R. nasutus-R. neglectus or R. prolixus-R. robustus species pairs, there were clear-cut differences between them; the median process of R. nasutus-R. neglectus is stout and subtriangular whereas that of R. prolixus-R. robustus is more narrow and elongated. The basal width of the process, classically used to separate R. robustus from R. prolixus and R. nasutus from R. neglectus, seems to have little taxonomic value. Other characters which have been assumed to be species-specific should be subjected to a similar quantitative analysis.

Characterization of (GT)n and (CT)n microsatellites in two insect species: Apis mellifera and Bombus terrestris

A set of 52 (CT)n and 23 (GT)n microsatellites in honeybee, 24 (CT)n and 2 (GT)n microsatellites in bumble-bee (n > 6) have been isolated from partial genomic libraries and sequenced. On average, (CT)n and (GT)n microsatellites occur every 15 kb and 34 kb in honeybee and every 40 kb and 500 kb in bumble-bee, respectively. The prevailing categories are imperfect repeats for (CT)n microsatellites in bumble-bee, and perfect repeats for both (CT)n and (GT)n microsatellites in honey-bee. Comparisons with data available in vertebrates indicate a lower proportion of perfect repeats in bees but length distributions are very similar regardless the phylum. This result extends to insects the concept of an evolutionary conservation for quantitative and qualitative characteristics of (CT)n and (GT)n microsatellites. Many (CT)n and (GT)n repeats are surrounded with various types of microsatellites, revealing an associative distribution of short repeat sequences. As expected, a high level of intrapopulational polymorphism has been found with one tested honeybee microsatellite. Also, flanking regions of this microsatellite are similar enough to allow PCR amplification in several other species of Apis and Bombus.

Psychosexual attitudes in the female following sterilization

This study represents a three year follow-up, summarizing the psychosexual attitudes of 120 patients who were sterilized with tubal occlusion by one of three methods: culdoscopy, laparoscopy or postpartum laparotomy. The results indicate that most patients had a favorable impression of the procedure with little significant change in their sexual habits. Eight per cent of patients expressed regret at not being able to have more children. The frequency of coitus remained largely unchanged.