RESUMEN

The males of many species of New World Phlebotomines produce volatile terpenoid chemicals, shown in Lutzomyia longipalpis s.l. to be sex/aggregation pheromones. Pheromone is produced by secretory cells which surround a cuticular reservoir which collects the pheromone and passes it through a cuticular duct to the surface of the insect. The pheromone then passes through specialised cuticular structures on the abdominal surface prior to evaporation. The shape and distribution of the specialised structures are highly diverse and differ according to species. In this study we used SEM to examine the interior cuticular pheromone collection and transport structures of 3 members of the Lu. longipalpis s.l. species complex and Migonemyia migonei. We found a new structure which we have called the manifold which appears to be a substantial extension of the interior tergal cuticle connected in-line with the cuticular duct and reservoir. The manifold of the Campo Grande member of the complex is longer and wider than the Jacobina member whereas the manifold of the Sobral member was shorter than both other members of the complex. Overall, the secretory apparatus of the Sobral member was smaller than the other two. The manifold of M. migonei was very different to those found in Lu. longipalpis s.l. and was positioned in a pit-like structure within the tergal cuticle. The secretory reservoir was connected by a short duct to the manifold. Differences in the size and shape of the manifold may be related to the chemical structure of the pheromone and may have taxonomic value. Examination of the interior cuticle by SEM may help to locate the secretory apparatus of vector species where pheromonal activity has been inferred from behavioural studies but the external secretory structures or pheromones have not yet been found.

Asunto(s)

Psychodidae/anatomía & histología , Psychodidae/metabolismo , Atractivos Sexuales/metabolismo , Abdomen/anatomía & histología , Animales , Femenino , Masculino

RESUMEN

Until vaccines and effective therapeutics become available, the practical solution to transit safely out of the current coronavirus disease 19 (CoVID-19) lockdown may include the implementation of an effective testing, tracing and tracking system. However, this requires a reliable and clinically validated diagnostic platform for the sensitive and specific identification of SARS-CoV-2. Here, we report on the development of a de novo, high-resolution and comparative genomics guided reverse-transcribed loop-mediated isothermal amplification (LAMP) assay. To further enhance the assay performance and to remove any subjectivity associated with operator interpretation of results, we engineered a novel hand-held smart diagnostic device. The robust diagnostic device was further furnished with automated image acquisition and processing algorithms and the collated data was processed through artificial intelligence (AI) pipelines to further reduce the assay run time and the subjectivity of the colorimetric LAMP detection. This advanced AI algorithm-implemented LAMP (ai-LAMP) assay, targeting the RNA-dependent RNA polymerase gene, showed high analytical sensitivity and specificity for SARS-CoV-2. A total of ~200 coronavirus disease (CoVID-19)-suspected NHS patient samples were tested using the platform and it was shown to be reliable, highly specific and significantly more sensitive than the current gold standard qRT-PCR. Therefore, this system could provide an efficient and cost-effective platform to detect SARS-CoV-2 in resource-limited laboratories.

Asunto(s)

Inteligencia Artificial , Betacoronavirus/aislamiento & purificación , Infecciones por Coronavirus/virología , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Amplificación de Ácido Nucleico/métodos , Neumonía Viral/virología , Animales , COVID-19 , Prueba de COVID-19 , Chlorocebus aethiops , Técnicas de Laboratorio Clínico/métodos , Infecciones por Coronavirus/diagnóstico , Perros , Humanos , Células de Riñón Canino Madin Darby , Pandemias , Neumonía Viral/diagnóstico , ARN Viral/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , SARS-CoV-2 , Sensibilidad y Especificidad , Células Vero

RESUMEN

Loop ileostomy is an effective procedure to protect downstream intestinal anastomoses. Ileostomy reversal surgery is often performed within 12 months of formation but is associated with substantial morbidity due to severe post-surgical complications. Distal ileum is deprived of enteral nutrition and rendered inactive, often becoming atrophied and fibrotic. This study aimed to investigate the microbial and morphological changes that occur in the defunctioned ileum following loop ileostomy-mediated fecal stream diversion. Functional and defunctioned ileal resection tissue was obtained at the time of loop-ileostomy closure. Intrapatient comparisons, including histological assessment of morphology and epithelial cell proliferation, were performed on paired samples using the functional limb as control. Mucosal-associated microflora was quantified via determination of 16S rRNA gene copy number using qPCR analysis. DGGE with Sanger sequencing and qPCR methods profiled microflora to genus and phylum level, respectively. Reduced villous height and proliferation confirmed atrophy of the defunctioned ileum. DGGE analysis revealed that the microflora within defunctioned ileum is less diverse and convergence between defunctioned microbiota profiles was observed. Candidate Genera, notably Clostridia and Streptococcus, reduced in relative terms in defunctioned ileum. We conclude that Ileostomy-associated nutrient deprivation results in dysbiosis and impaired intestinal renewal in the defunctioned ileum. Altered host-microbial interactions at the mucosal surface likely contribute to the deterioration in homeostasis and thus may underpin numerous postoperative complications. Strategies to sustain the microflora before reanastomosis should be investigated.

Asunto(s)

Biota , Disbiosis/etiología , Ileostomía/efectos adversos , Íleon/microbiología , Adulto , Anciano , Carga Bacteriana , Femenino , Humanos , Masculino , Persona de Mediana Edad , ARN Ribosómico 16S/genética , Reacción en Cadena en Tiempo Real de la Polimerasa

RESUMEN

INTRODUCTION: Suppressor of cytokine signaling 3 (SOCS3) is a tumour suppressor, limiting intestinal epithelial cell (IEC) proliferation in acute inflammation, and tumour growth, but little is known regarding its role in mucosal homeostasis. Resistance to the intestinal helminth Trichuris muris relies on an "epithelial escalator" to expel the parasite. IEC turnover is restricted by parasite-induced indoleamine 2,3-dioxygenase (IDO). METHODS: Mice with or without conditional knockout of SOCS3 were infected with T. muris. Crypt depth, worm burden, and proliferating cells and IDO were quantified. SOCS3 knockdown was also performed in human IEC cell lines. RESULTS: Chronic T. muris infection increased expression of SOCS3 in wild-type mice. Lack of IEC SOCS3 led to a modest increase in epithelial turnover. This translated to a lower worm burden, but not complete elimination of the parasite suggesting a compensatory mechanism, possibly IDO, as seen in SOCS3 knockdown. CONCLUSIONS: We report that SOCS3 impacts on IEC turnover following T. muris infection, potentially through enhancement of IDO. IDO may dampen the immune response which can drive IEC hyperproliferation in the absence of SOCS3, demonstrating the intricate interplay of immune signals regulating mucosal homeostasis, and suggesting a novel tumour suppressor role of SOCS3.

Asunto(s)

Homeostasis/inmunología , Inmunidad Mucosa , Mucosa Intestinal/inmunología , Modelos Inmunológicos , Proteína 3 Supresora de la Señalización de Citocinas/inmunología , Animales , Línea Celular , Homeostasis/genética , Humanos , Indolamina-Pirrol 2,3,-Dioxigenasa/genética , Indolamina-Pirrol 2,3,-Dioxigenasa/inmunología , Inflamación/genética , Inflamación/inmunología , Inflamación/parasitología , Inflamación/patología , Mucosa Intestinal/parasitología , Mucosa Intestinal/patología , Ratones , Ratones Noqueados , Proteína 3 Supresora de la Señalización de Citocinas/genética , Tricuriasis/genética , Tricuriasis/inmunología , Tricuriasis/patología , Trichuris/inmunología

RESUMEN

A single layer of intestinal epithelial cells (IEC) lines the entire gastrointestinal tract and provides the first line of defense and barrier against an abundance of microbial stimuli. IEC homeostasis and repair are mediated through microbe-sensing Toll-like receptor (TLR)-induced inflammatory pathways. Increasing evidence supports a role of suppressor of cytokine signaling 3 (SOCS3) as a modulator of IEC turnover, balancing controlled repair and replenishment with excessive IEC proliferation predisposing to dysplasia and cancer. Our data indicate that SOCS3 can limit microbial-induced IEC repair, potentially through promoting tumor necrosis factor-α (TNF-α) and limiting TNFR2 expression. Activation of TLR5 signaling pathways, compared with other TLR, increases TNF-α mRNA in a dose-dependent manner and SOCS3 enhances TLR5-induced TNF-α. We also show that flagellin promotes transcription of TNFR2 and that SOCS3 limits this expression, presenting a mechanism of SOCS3 action. Our data also support the role of microbial ligands in epithelial wound healing and suggest that a functional consequence of increased TNF-α is reduced wound healing. These results provide further evidence to support the regulatory role of epithelial SOCS3 in intestinal health and suggest that the increased expression of SOCS3 observed in IBD may serve to perpetuate "inflammation" by promoting TNF-α production and limiting epithelial repair in response to commensal microflora.

Asunto(s)

Colon/metabolismo , Células Epiteliales/metabolismo , Enfermedades Inflamatorias del Intestino/metabolismo , Mucosa Intestinal/metabolismo , Proteínas Supresoras de la Señalización de Citocinas/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Células CACO-2 , Colon/efectos de los fármacos , Colon/inmunología , Colon/microbiología , Relación Dosis-Respuesta a Droga , Células Epiteliales/efectos de los fármacos , Células Epiteliales/inmunología , Células Epiteliales/microbiología , Humanos , Factores Inmunológicos/farmacología , Enfermedades Inflamatorias del Intestino/inmunología , Enfermedades Inflamatorias del Intestino/microbiología , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/microbiología , Permeabilidad , ARN Mensajero/metabolismo , Receptores Tipo II del Factor de Necrosis Tumoral/genética , Receptores Tipo II del Factor de Necrosis Tumoral/metabolismo , Proteína 3 Supresora de la Señalización de Citocinas , Proteínas Supresoras de la Señalización de Citocinas/genética , Receptor Toll-Like 5/agonistas , Receptor Toll-Like 5/metabolismo , Transfección , Factor de Necrosis Tumoral alfa/genética , Regulación hacia Arriba , Cicatrización de Heridas

RESUMEN

OBJECTIVE: To determine personal birth preferences of obstetricians in various clinical scenarios, in particular elective caesarean section for maternal request. To determine actual rates of modes of deliveries amongst the same group. To compare the obstetrician's mode of delivery rates, to the general population. STUDY DESIGN: Following ethical approval, a piloted online survey link was sent via email to 242 current obstetricians and gynaecologists, (consultants and trainees) in South West England. Mode of delivery results were compared to regional and national population data, using Hospital Episode Statistics and subjected to statistical analysis. RESULTS: The response rate was 68%. 90% would hypothetically plan a vaginal delivery, 10% would consider a caesarean section in an otherwise uncomplicated primiparous pregnancy. Of the 94/165 (60%) respondents with children (201 children), mode of delivery for the first born child; normal vaginal delivery 48%, caesarean section 26.5% (elective 8.5%, emergency 18%), instrumental 24.5% and vaginal breech 1%. Only one chose an elective caesarean for maternal request. During 2006-2011 obstetricians have the same overall actual modes of birth as the population (p=0.9). CONCLUSIONS: Ten percent of obstetricians report they would consider requesting caesarean section for themselves/their partner, which is the lowest rate reported within UK studies. However only 1% actually had a caesarean solely for maternal choice. When compared to regional/national statistics obstetricians currently have modes of delivery that are not significantly different than the population and suggests that they choose non interventional delivery if possible.

Asunto(s)

Conducta de Elección , Parto Obstétrico/estadística & datos numéricos , Ginecología/estadística & datos numéricos , Obstetricia/estadística & datos numéricos , Cesárea/estadística & datos numéricos , Parto Obstétrico/métodos , Procedimientos Quirúrgicos Electivos/estadística & datos numéricos , Inglaterra , Femenino , Humanos , Masculino , Paridad

RESUMEN

BACKGROUND: Oligodendroglial tumors with 1p/19q loss are more likely to be chemosensitive and have longer survival than those with intact 1p/19q, but not all respond to chemotherapy, warranting investigation of the biological basis of chemosensitivity. METHODS: Gene expression profiling was performed using amplified antisense RNA from 28 oligodendroglial tumors treated with chemotherapy [26 serial stereotactic biopsy, 2 resection]. Expression of differentially expressed genes was validated by real-time PCR. RESULTS: Unsupervised hierarchical clustering showed clustering of multiple samples from the same case in 14/17 cases and identified subgroups associated with tumor grade and 1p/19q status. 176 genes were differentially expressed, 164 being associated with 1p/19q loss (86% not on 1p or 19q). 94 genes differed between responders and non-responders to chemotherapy; 12 were not associated with 1p/19q loss. Significant differential expression was confirmed in 11/13 selected genes. Novel genes associated with response to therapy included SSBP2, GFRA1, FAP and RASD1. IQGAP1, INA, TGIF1, NR2F2 and MYCBP were differentially expressed in oligodendroglial tumors with 1p/19q loss. CONCLUSION: Gene expression profiling using serial stereotactic biopsies indicated greater homogeneity within tumors than between tumors. Genes associated with 1p/19q status or response were identified warranting further elucidation of their role in oligodendroglial tumors.

Asunto(s)

Regulación Neoplásica de la Expresión Génica , Oligodendroglioma/genética , Adulto , Anciano , Desequilibrio Alélico/genética , Cromosomas Humanos Par 1/genética , Cromosomas Humanos Par 19/genética , Análisis por Conglomerados , Femenino , Perfilación de la Expresión Génica , Genes Relacionados con las Neoplasias/genética , Humanos , Masculino , Persona de Mediana Edad , Oligodendroglioma/tratamiento farmacológico , Análisis de Componente Principal , Reacción en Cadena en Tiempo Real de la Polimerasa , Reproducibilidad de los Resultados , Resultado del Tratamiento , Adulto Joven

RESUMEN

BACKGROUND: Oligodendroglial tumors with 1p/19q loss are more likely to be chemosensitive and have longer survival than those with intact 1p/19q, but not all respond to chemotherapy, warranting investigation of the biological basis of chemosensitivity. METHODS: Gene expression profiling was performed using amplified antisense RNA from 28 oligodendroglial tumors treated with chemotherapy (26 serial stereotactic biopsy, 2 resection). Expression of differentially expressed genes was validated by real-time PCR. RESULTS: Unsupervised hierarchical clustering showed clustering of multiple samples from the same case in 14/17 cases and identified subgroups associated with tumor grade and 1p/19q status. 176 genes were differentially expressed, 164 being associated with 1p/19q loss (86% not on 1p or 19q). 94 genes differed between responders and non-responders to chemotherapy; 12 were not associated with 1p/19q loss. Significant differential expression was confirmed in 11/13 selected genes. Novel genes associated with response to therapy included SSBP2, GFRA1, FAP and RASD1. IQGAP1, INA, TGIF1, NR2F2 and MYCBP were differentially expressed in oligodendroglial tumors with 1p/19q loss. CONCLUSION: Gene expression profiling using serial stereotactic biopsies indicated greater homogeneity within tumors than between tumors. Genes associated with 1p/19q status or response were identified warranting further elucidation of their role in oligodendroglial tumors.

Asunto(s)

Astrocitoma/genética , Neoplasias Encefálicas/genética , Oligodendroglioma/genética , Adulto , Anciano , Cromosomas Humanos Par 1/genética , Cromosomas Humanos Par 19/genética , Análisis por Conglomerados , Resistencia a Antineoplásicos/genética , Femenino , Expresión Génica , Humanos , Masculino , Persona de Mediana Edad , Análisis de Secuencia por Matrices de Oligonucleótidos , Análisis de Componente Principal , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Adulto Joven

RESUMEN

We report that nanoparticulate zirconia (ZrO(2)) catalyzes both growth of single-wall and multiwall carbon nanotubes (CNTs) by thermal chemical vapor deposition (CVD) and graphitization of solid amorphous carbon. We observe that silica-, silicon nitride-, and alumina-supported zirconia on silicon nucleates single- and multiwall carbon nanotubes upon exposure to hydrocarbons at moderate temperatures (750 degrees C). High-pressure, time-resolved X-ray photoelectron spectroscopy (XPS) of these substrates during carbon nanotube nucleation and growth shows that the zirconia catalyst neither reduces to a metal nor forms a carbide. Point-localized energy-dispersive X-ray spectroscopy (EDAX) using scanning transmission electron microscopy (STEM) confirms catalyst nanoparticles attached to CNTs are zirconia. We also observe that carbon aerogels prepared through pyrolysis of a Zr(IV)-containing resorcinol-formaldehyde polymer aerogel precursor at 800 degrees C contain fullerenic cage structures absent in undoped carbon aerogels. Zirconia nanoparticles embedded in these carbon aerogels are further observed to act as nucleation sites for multiwall carbon nanotube growth upon exposure to hydrocarbons at CVD growth temperatures. Our study unambiguously demonstrates that a nonmetallic catalyst can catalyze CNT growth by thermal CVD while remaining in an oxidized state and provides new insight into the interactions between nanoparticulate metal oxides and carbon at elevated temperatures.

RESUMEN

IgASE1, a C18-Delta9-polyunsaturated fatty acid-specific fatty acid elongase component from Isochrysis galbana, contains a variant histidine box (his-box) with glutamine replacing the first histidine of the conserved histidine-rich motif present in all other known equivalent proteins. The importance of glutamine and other variant amino acid residues in the his-box of IgASE1 was determined by site-directed mutagenesis. Results showed that all the variation in amino acid sequence between this motif in IgASE1 and the consensus sequences of other elongase components was required for optimum enzyme activity. The substrate specificity was shown to be unaffected by these changes suggesting that components of the his-box are not directly responsible for substrate specificity.

Asunto(s)

Acetiltransferasas/metabolismo , Eucariontes/genética , Ácidos Grasos Insaturados/metabolismo , Acetiltransferasas/química , Acetiltransferasas/genética , Secuencia de Aminoácidos , Secuencia de Bases , Sitios de Unión , Cartilla de ADN , Eucariontes/enzimología , Elongasas de Ácidos Grasos , Cinética , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Reacción en Cadena de la Polimerasa , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Especificidad por Sustrato