Determination of an Interaction Network between an Extracellular Bacterial Pathogen and the Human Host

A major gap in understanding infectious diseases is the lack of information about molecular interaction networks between pathogens and the human host. Haemophilus ducreyi causes the genital ulcer disease chancroid in adults and is a leading cause of cutaneous ulcers in children in the tropics. We developed a model in which human volunteers are infected on the upper arm with H. ducreyi until they develop pustules. To define the H. ducreyi and human interactome, we determined bacterial and host transcriptomic and host metabolomic changes in pustules. We found that in vivo H. ducreyi transcripts were distinct from those in the inocula, as were host transcripts in pustule and wounded control sites. Many of the upregulated H. ducreyi genes were found to be involved in ascorbic acid and anaerobic metabolism and inorganic ion/nutrient transport. The top 20 significantly expressed human pathways showed that all were involved in immune responses. We generated a bipartite network for interactions between host and bacterial gene transcription; multiple positively correlated networks contained H. ducreyi genes involved in anaerobic metabolism and host genes involved with the immune response. Metabolomic studies showed that pustule and wounded samples had different metabolite compositions; the top ion pathway involved ascorbate and aldarate metabolism, which correlated with the H. ducreyi transcriptional response and upregulation of host genes involved in ascorbic acid recycling. These data show that an interactome exists between H. ducreyi and the human host and suggest that H. ducreyi exploits the metabolic niche created by the host immune response.IMPORTANCE Dual RNA sequencing (RNA-seq) offers the promise of determining an interactome at a transcriptional level between a bacterium and the host but has yet to be done on any bacterial infection in human tissue. We performed dual RNA-seq and metabolomics analyses on wounded and infected sites following experimental infection of the arm with H. ducreyi Our results suggest that H. ducreyi survives in an abscess by utilizing l-ascorbate as an alternative carbon source, possibly taking advantage of host ascorbic acid recycling, and that H. ducreyi also adapts by upregulating genes involved in anaerobic metabolism and inorganic ion and nutrient transport. To our knowledge, this is the first description of an interaction network between a bacterium and the human host at a site of infection

Acid-modified clays as green catalysts for the hydrolysis of hemicellulosic oligosaccharides

The hydrolysis of hemicellulosic oligosaccharides (OS) was investigated using acid-activated clays (prepared from natural Porto Santo montmorillonite clay) as catalysts. Acid activation was performed in HCl solution or with aluminium exchange. The clay catalysts were characterized by XRD, N2 adsorption isotherms, CEC, FTIR, titration of acid sites in water and adsorption of sugars and disaccharides. They were tested for the hydrolysis of a model compound, maltose, and of OS-rich liquor from rice straw fractionation. The HCl-activated clays were the most efficient catalysts for maltose hydrolysis. It was demonstrated that the hydrolysis of OS into monomer sugars over a clay catalyst is technically feasible and that this reaction leads to the selective removal of glucose, arabinose and acetic acid side groups from the OS structure, thus yielding simpler xylo-oligosaccharide chains. Furthermore, no significant conversion of monomer sugars into furans was observed

O uso da hibridação in situ com fluorescência no diagnóstico de mosaicismo oculto: a propósito de três casos de anomalias de cromossomos sexuais

FISH has been used as a complement to classical cytogenetics in the detection of mosaicism in sex chromosome anomalies. The aim of this study is to describe three cases in which the final diagnosis could only be achieved by FISH. Case 1 was an 8-year-old 46,XY girl with normal female genitalia referred to our service because of short stature. FISH analysis of lymphocytes with probes for the X and Y centromeres identified a 45,X/46,X,idic(Y) constitution, and established the diagnosis of Turner syndrome. Case 2 was a 21-month-old 46,XY boy with genital ambiguity (penile hypospadias, right testis, and left streak gonad). FISH analysis of lymphocytes and buccal smear identified a 45,X/46,XY karyotype, leading to diagnosis of mixed gonadal dysgenesis. Case 3 was a 47,XYY 19-year-old boy with delayed neuromotor development, learning disabilities, psychological problems, tall stature, small testes, elevated gonadotropins, and azoospermia. FISH analysis of lymphocytes and buccal smear identified a 47,XYY/48,XXYY constitution. Cases 1 and 2 illustrate the phenotypic variability of the 45,X/46,XY mosaicism, and the importance of detection of the 45,X cell line for proper management and follow-up. In case 3, abnormal gonadal function could be explained by the 48,XXYY cell line. The use of FISH in clinical practice is particularly relevant when classical cytogenetic analysis yields normal or uncertain results in patients with features of sex chromosome aneuploidy. Arq Bras Endocrinol Metab. 2012;56(8):545-51FISH tem sido usado como um complemento para a citogenética clássica na detecção de mosaicismo em anomalias de cromossomos sexuais. O objetivo deste trabalho é descrever três casos nos quais o diagnóstico final só foi obtido por meio de FISH. O caso 1 é uma menina de 8 anos, 46,XY, com genitália feminina normal, encaminhada ao nosso setor devido à baixa estatura. A análise de linfócitos por FISH com sondas centroméricas de X e Y identificou a constituição 45,X/46,X,idic(Y) e estabeleceu o diagnóstico de síndrome de Turner. O caso 2 é um menino de 21 meses, 46,XY, com ambiguidade genital (hipospadia peniana, testículo à direita e gônada disgenética à esquerda). FISH de linfócitos e mucosa oral identificou o cariótipo 45,X/46,XY, levando ao diagnóstico de disgenesia gonadal mista. O caso 3 é um rapaz de 19 anos, 47,XYY, com atraso de desenvolvimento neuromotor, dificuldade de aprendizado, problemas psicológicos, alta estatura, testículos pequenos, gonadotrofinas elevadas e azoospermia. FISH de linfócitos e mucosa oral identificou a constituição 47,XYY/48,XXYY. Os casos 1 e 2 ilustram a variabilidade fenotípica do mosaico 45,X/46,XY e a importância da detecção da linhagem 45,X na avaliação e na condução dos casos. No caso 3, a função gonadal anormal pôde ser explicada pela linhagem 48,XXYY. O uso de FISH na prática clínica é particularmente relevante quando a análise citogenética clássica traz resultados normais ou incertos em pacientes com quadro sugestivo de uma aneuploidia de cromossomos sexuais. Arq Bras Endocrinol Metab. 2012;56(8):545-51Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Universidade Estadual de Campinas Faculdade de Ciências Médicas Departamento de Genética MédicaUnicamp FCM Grupo Interdisciplinar de Estudos da Determinação e Diferenciação do SexoUnicamp FCM Departamento de PediatriaUniversidade Federal de São Paulo (UNIFESP) Escola Paulista de Medicina Departamento de PediatriaUNIFESP, EPM, Depto. de PediatriaSciEL

Maternal time investment in caregiving activities to promote early childhood development: evidence from rural India

INTRODUCTION: Intervention strategies that seek to improve early childhood development outcomes are often targeted at the primary caregivers of children, usually mothers. The interventions require mothers to assimilate new information and then act upon it by allocating sufficient physical resources and time to adopt and perform development promoting behaviours. However, women face many competing demands on their resources and time, returning to familiar habits and behaviours. In this study, we explore mothers' allocation of time for caregiving activities for children under the age of 2, nested within a cluster randomised controlled trial of a nutrition and care for development intervention in rural Haryana, India. METHODS: We collected quantitative maternal time use data at two time points in rural Haryana, India, using a bespoke survey instrument. Data were collected from 704 mothers when their child was 12 months old, and 603 mothers when their child was 18 months old. We tested for significant differences in time spent by mothers on different activities when children are 12 months of age vs. 18 months of age between arms as well as over time, using linear regression. As these data were collected within a randomised controlled trial, we adjusted for clusters using random effects when testing for significant differences between the two time points. RESULTS: At both time points, no statistically significant difference in maternal time use was found between arms. On average, mothers spent most of their waking time on household chores (over 6 h and 30 min) at both time points. When children were aged 12 months, approximately three and a half hours were spent on childcare activities for children under the age of 2 years. When children were 18 months old, mothers spent more time on income generating activities (30 min) than when the children were 12 years old, and on leisure (approximately 4 h and 30 min). When children were 18 months old, less time was spent on feeding/breastfeeding children (30 min less) and playing with children (15 min). However, mothers spent more time talking or reading to children at 18 months than at 12 months. CONCLUSION: We find that within a relatively short period of time in early childhood, maternal (or caregiver) time use can change, with time allocation being diverted away from childcare activities to others. This suggests that changing maternal time allocation in resource poor households may be quite challenging, and not allow the uptake of new and/or optimal behaviours