The Chlamydia pneumoniae invasin protein Pmp21 recruits the EGF receptor for host cell entry.

Infection of mammalian cells by the strictly intracellular pathogens Chlamydiae requires adhesion and internalization of the infectious Elementary Bodies (EBs). The components of the latter step were unknown. Here, we identify Chlamydia pneumoniae Pmp21 as an invasin and EGFR as its receptor. Modulation of EGFR surface expression evokes correlated changes in EB adhesion, internalization and infectivity. Ectopic expression of EGFR in EGFR-negative hamster cells leads to binding of Pmp21 beads and EBs, thus boosting the infection. EB/Pmp21 binding and invasion of epithelial cells results in activation of EGFR, recruitment of adaptors Grb2 and c-Cbl and activation of ERK1/2, while inhibition of EGFR or MEK kinase activity abrogates EB entry, but not attachment. Binding of Grb2 and c-Cbl by EGFR is essential for infection. This is the first report of an invasin-receptor interaction involved in host-cell invasion by any chlamydial species.

Measuring child awareness for adult symptomatic HIV using a verbal assessment tool: concordance between adult-child dyads on adult HIV-associated symptoms and illnesses.

OBJECTIVES: This study assessed children's awareness for adult HIV-associated symptoms and illnesses using a verbal assessment tool by analysing inter-rater reliability between adult-child dyads. This study also evaluated sociodemographic and household characteristics associated with child awareness of adult symptomatic HIV. METHODS: A cross-sectional survey using a representative community sample of adult-child dyads (N=2477 dyads) was conducted in KwaZulu-Natal, South Africa. Analyses focused on a subsample (n=673 adult-child dyads) who completed verbal assessment interviews for symptomatic HIV. We used an existing validated verbal autopsy approach, originally designed to determine AIDS-related deaths by adult proxy reporters. We adapted this approach for use by child proxy reporters for reporting on HIV-associated symptoms and illnesses among living adults. Analyses assessed whether children could reliably report on adult HIV-associated symptoms and illnesses and adult provisional HIV status. RESULTS: Adult-child pairs concurred above the 65th percentile for 9 of the 10 HIV-associated symptoms and illnesses with sensitivities ranging from 10% to 100% and specificities ranging from 20% to 100%. Concordant reporting between adult-child dyads for the adult's provisional HIV status was 72% (sensitivity=68%, specificity=73%). Children were more likely to reliably match adult's reports of provisional HIV status when they lived in households with more household members, and households with more robust socioeconomic indicators including access to potable water, food security and television. CONCLUSIONS: Children demonstrate awareness of HIV-associated symptoms and illnesses experienced by adults in their household. Children in households with greater socioeconomic resources and more household members were more likely to reliably report on the adult's provisional HIV status.

Subunit δ is the key player for assembly of the H(+)-translocating unit of Escherichia coli F(O)F1 ATP synthase.

The ATP synthase (F(O)F1) of Escherichia coli couples the translocation of protons across the cytoplasmic membrane to the synthesis or hydrolysis of ATP. This nanomotor is composed of the rotor c10γε and the stator ab2α3ß3δ. To study the assembly of this multimeric enzyme complex consisting of membrane-integral as well as peripheral hydrophilic subunits, we combined nearest neighbor analyses by intermolecular disulfide bond formation or purification of partially assembled F(O)F1 complexes by affinity chromatography with the use of mutants synthesizing different sets of F(O)F1 subunits. Together with a time-delayed in vivo assembly system, the results demonstrate that F(O)F1 is assembled in a modular way via subcomplexes, thereby preventing the formation of a functional H(+)-translocating unit as intermediate product. Surprisingly, during the biogenesis of F(O)F1, F1 subunit δ is the key player in generating stable F(O). Subunit δ serves as clamp between ab2 and c10α3ß3γε and guarantees that the open H(+) channel is concomitantly assembled within coupled F(O)F1 to maintain the low membrane proton permeability essential for viability, a general prerequisite for the assembly of multimeric H(+)-translocating enzymes.

Using program impact pathways to understand and improve program delivery, utilization, and potential for impact of Helen Keller International's homestead food production program in Cambodia.

BACKGROUND: Evidence of the impact of homestead food production programs on nutrition outcomes such as anemia and growth is scant. In the absence of information on program impact pathways, it is difficult to understand why these programs, which have been successful in increasing intake of micronutrient-rich foods, have had such limited documented impact on nutrition outcomes. OBJECTIVE: To conduct a process evaluation of Helen Keller International's (HKI's) homestead food production program in Cambodia to assess whether the program was operating as planned (in terms of design, delivery, and utilization) and to identify ways in which the program might need to be strengthened in order to increase its potential for impact. METHODS: A program theory framework, which laid out the primary components along the hypothesized program impact pathways, was developed in collaboration with HKI and used to design the research. Semistructured interviews and focus group discussions with program beneficiaries (n = 36 and 12, respectively), nonbeneficiaries (n = 12), and program implementers (n = 17 and 2, respectively) and observations of key program delivery points, including health and nutrition training sessions (n = 6), village model farms (n = 6), and household gardens of beneficiaries (n = 36) and nonbeneficiaries (n = 12), were conducted to assess the delivery and utilization of the primary program components along the impact pathways. RESULTS: The majority of program components were being delivered and utilized as planned. However, challenges with some of the key components posited to improve outcomes such as anemia and growth were noted. Among these were a gap in the expected pathway from poultry production to increased intake of eggs and poultry meat, and some weaknesses in the delivery of the health and nutrition training sessions and related improvements in knowledge among the village health volunteers and beneficiaries. CONCLUSIONS: Although the program has been successful in delivering the majority of the program components as planned and has documented achievements in improving household production and intake of micronutrient-rich foods, it is likely that strengthening delivery and increasing utilization of some program components would increase its potential for nutritional impacts. This research has highlighted the importance of designing a program theory framework and assessing the components that lie along the primary program impact pathways to optimize program service delivery and utilization and, in turn, potential for impact.

Parents' Experience With a Mobile Health Intervention to Influence Human Papillomavirus Vaccination Decision Making: Mixed Methods Study.

BACKGROUND: Human papillomavirus (HPV)-attributed cancers are preventable, yet HPV vaccination rates severely lag behind other adolescent vaccinations. HPVcancerFree (HPVCF) is a mobile health (mHealth) intervention developed to influence parental HPV vaccination decision making by raising awareness of HPV, reducing HPV vaccination barriers, and enabling HPV vaccination scheduling and reminders through a smartphone app. Evaluating the user experience of mHealth interventions is a vital component in assessing their quality and success but tends to be underreported in mHealth intervention evaluation. OBJECTIVE: We aimed to evaluate the user experience of HPVCF, an HPV cancer prevention app designed for a pediatric clinic network, using mixed methods data collected from log files, survey measures, and qualitative feedback. METHODS: Study data were evaluated from parents in a large US pediatric clinic network using HPVCF in the treatment study condition of a group randomized controlled trial. Log data captured HPVCF retention and use. Postintervention rating scales and items assessed HPVCF utility, usefulness, understandability, appeal, credibility, and perceived impact. Overall quality was evaluated using the user version of the Mobile Application Rating Scale (uMars). Open-ended responses assessed parent recommendations for HPVCF enhancement. RESULTS: The 98 parents were mainly female (n=94, 96%), 41 (5.67) years of age, college educated (n=55, 56%), and White and non-Hispanic (n=55, 56%) and had private health insurance for their children (n=75, 77%). Parents used HPVCF 197 times, with the average visit duration approximating 3.5 minutes. The uMARS app quality score was positively skewed (4.2/5.0). Mean ratings were highest for information (4.46 [SD 0.53]) and lowest for engagement (3.74 [SD 0.69]). In addition, of 95 parents, 45 (47%) rated HPVCF as helpful in HPV vaccination decision making and 16 (17%) attributed HPV vaccine initiation to HPVCF. Parents reported that HPVCF increased their awareness (84/95, 88%), knowledge (84/95, 88%), and HPV vaccination intentions (64/95, 67%). Most of the 98 parents rated the 4 HPVCF components as useful (72-92 [73%-94%]). Parents also agreed that HPVCF is clear (86/95, 91%), accurate (86/95, 91%), and more helpful than other HPV vaccine information they had received (89/95, 94%) and that they would recommend it to others (81/95, 85%). In addition, parents suggested ways to increase awareness and engagement with the app, along with opportunities to enhance the content and functionality. CONCLUSIONS: HPVCF was well received by parents and performed well on indicators of quality, usefulness, utility, credibility, and perceived impact. This study contributes a multimethod and multimeasure evaluation to the growing body of literature focused on assessing the user experience of patient-focused technology-mediated applications for HPV education.

AVPCancerFree: Impact of a digital behavior change intervention on parental HPV vaccine -related perceptions and behaviors.

Parent hesitancy contributes to reduced HPV vaccination rates. The HPVcancerfree app (HPVCF) was designed to assist parents in making evidence-based decisions regarding HPV vaccination. This study examined if parents of vaccine-eligible youth (11-12 yrs.) who use HPVCF in addition to usual care demonstrate significantly more positive intentions and attitudes toward HPV vaccination and greater HPV vaccination rates compared to those not using HPVCF. Clinics (n = 51) within a large urban pediatric network were randomly assigned to treatment (HPVCF + usual care) or comparison (usual care only) conditions in a RCT conducted between September 2017 and February 2019. Parents completed baseline and 5-month follow-up surveys. Participant-level analysis determined 1) change in HPV vaccination initiation behavior and related psychosocial determinants and 2) predictors of HPV vaccine initiation. Parents (n = 375) who completed baseline and 5-month follow-up surveys were female (95.2%), 40.8 (±5.8) yrs. married (83.7%), employed (68.3%), college educated (61.9%), and privately insured (76.5%). Between-group analysis of HPVCF efficacy demonstrated that parents assigned to receive HPVCF significantly increased knowledge about HPV and HPV vaccination (p < .05). Parents who accessed content within HPVCF significantly increased knowledge about HPV & HPV vaccine (p < .01) and perceived effectiveness of HPV vaccine (p < .05). Change in HPV vaccine initiation was not significant. A multivariate model to describe predictors of HPV vaccine initiation demonstrated an association with Tdap and MCV vaccination adoption, positive change in perceived effectiveness of the HPV vaccine, and reduction in perceived barriers against HPV vaccination. HPVCF appears to be a feasible adjunct to the education received in usual care visits and reinforces the value of apps to support the important persuasive voice of the health-care provider in overcoming parent HPV vaccine hesitancy.

Parent Engagement with a Self-Tailored Cancer Prevention Digital Behavior Change Intervention: Exploratory Application of Affiliation Network Analysis.

Evaluating digital behavior change intervention engagement is complex and requires multidimensional and novel approaches that are emerging. The relationship and interdependence between engagement with the technology and engagement with the psychosocial or behavior change process often presents conceptual and evaluative challenges. Large objective data sets detailing technology use are plentiful but meaningful interpretation can be challenging at granular levels. Affiliation network analysis which describes two-mode network data may provide a novel approach to evaluate engagement of digital behavior change interventions. The purpose of this paper is to use affiliation network analysis as an exploratory method to describe, assess and visualize content-specific patterns underlying psychosocial characteristics related to HPV vaccine safety concerns of parents using the HPVcancerFree intervention. Results indicate that affiliation network analysis shows promise in supplementing existing methods to assess engagement of digital interventions.

Neuroimaging of eye position reveals spatial neglect.

Conjugate eye deviation describes the tonic horizontal deviation of the eyes in acute stroke patients. Here we investigate whether measuring patients' eye-in-head position in clinical magnetic resonance imaging or computed tomography scans obtained at admission shows a specific relationship to spatial neglect. We investigated 124 continuously admitted subjects with unilateral, first-ever left- or right-sided stroke. To control for the possibility that the degree of eye deviation is related to lesion size rather than spatial neglect, overall lesion volume was used as a covariate in the statistical analysis. Horizontal eye-in-head deviation on clinical brain scans appeared to be associated with spatial neglect rather than with brain damage per se. In contrast to the subject groups without the disorder, the patients with spatial neglect showed an eye-in-head position that was significantly deviated towards the ipsilesional right. Evaluation of eye-in-head position on clinical scans thus may be an additional helpful tool for diagnosing spatial neglect, particularly in the very early period of the stroke.

Informing Content and Feature Design of a Parent-Focused Human Papillomavirus Vaccination Digital Behavior Change Intervention: Synchronous Text-Based Focus Group Study.

BACKGROUND: Human papillomavirus (HPV) is a common and preventable sexually transmitted infection; however, vaccination rates in the United States among the target age group, which is 11-12 years, are lower than national goals. Interventions that address the barriers to and facilitators of vaccination are important for improving HPV vaccination rates. Web-based, text-based focus groups are becoming a promising method that may be well suited for conducting formative research to inform the design of digital behavior change intervention (DBCI) content and features that address HPV vaccination decision-making. OBJECTIVE: This study aims to explore parental HPV vaccination decision-making processes using a web-based, text-based focus group protocol to inform content and feature recommendations for an HPV prevention DBCI. METHODS: We conducted 4 web-based, text-based synchronous focus groups via Skype with the parents of patients aged 11-13 years within a large urban US pediatric clinic network. RESULTS: The 22 parents were mostly female, White, non-Hispanic college graduates, and they mostly had private health insurance for their children. Approximately half (14/25, 56%) of the parents' 11-13 year old children had initiated HPV vaccination. Most parents had experience using Skype (19/22, 86%). Approximately half (8/17, 47%) of parents expressed no preference for the focus group format, whereas 47% (8/17) requested a text-only chat format and 6% (1/17) requested an audiovisual format. The three main themes from the qualitative data were barriers to HPV vaccination, facilitators of HPV vaccination, and suggestions for improving the HPV vaccination clinic experience. A total of 11 intervention content and feature recommendations emerged from the themes, including addressing HPV knowledge barriers using trusted sources, designing for a family audience, focusing on the framing of messages, reporting reputable HPV research in a comprehensible format, and expanding the clinic visit experience. CONCLUSIONS: Synchronous text-based focus groups are feasible for conducting formative research on HPV vaccination decision-making. Among well-educated and well-resourced parents, there are barriers such as misinformation and facilitators such as pediatrician recommendations that influence HPV vaccination decision-making. Parents want to conduct their own HPV research as well as receive relevant HPV vaccination advice from their child's pediatrician. In addition, parents want an enhanced clinic visit experience that lets them access and connect to tailored information before and after clinic visits. The results gathered provide guidance for content and features that may inform a more responsive DBCI to address HPV vaccination decision-making among parents.

Public Health Entrepreneurship: A Novel Path for Training Future Public Health Professionals.

Background: As schools of public health adapt to the new Council on Public Health (CEPH) competencies there is increased relevance in training public health professionals in public health entrepreneurship. Public health entrepreneurship provides an alternate process to traditional academic approaches focusing on translating public health knowledge into effective, sustainable, and scalable solutions. Objective: This study reports student perceptions of public health entrepreneurship and training needs for successfully equipping future public health professionals. Methods: Focus groups were conducted in April 2018 with graduate public health students in pilot entrepreneurship courses at two U.S.-based CEPH-accredited schools of public health. Results: Participating students (n = 29) were mainly pursing MPH degrees (62%) within Health Management and Policy (38%) or Health Promotion/Global Health (31%) departments. Most students (52%) were between 21 and 30 years old. For 71% of students this was their first academic course with a focus on entrepreneurial thinking. Four themes emerged regarding public health entrepreneurship and training needs for becoming a successful public health professional of the future. Students confirmed a place for public health entrepreneurship in the emerging educational paradigm because it is action-oriented, skills-driven, and fosters innovation through inter-professional collaboration and cross-pollination of knowledge and skills between professional disciplines. Conclusions: The competencies required for public health entrepreneurship are in alignment with CEPH competencies and are well-received by the next generation of public health professionals as an adjunct but nascent approach to stimulate public health innovation.

Incidence of visual extinction after left versus right hemisphere stroke.

BACKGROUND AND PURPOSE: Generally it is accepted that spatial neglect occurs predominantly after stroke of the human right hemisphere. In contrast, it remained controversial whether extinction follows the same hemispheric asymmetry. The opinion prevails that the laterality of visual extinction is not as pronounced as it is for spatial neglect. METHODS: To directly compare the incidence of the 2 disorders within the same sample, spatial neglect and visual extinction were investigated during a 1-year period in 83 consecutively admitted patients with unilateral right or left hemisphere stroke. RESULTS: The incidence of visual extinction and of spatial neglect was not significantly different, neither after left hemisphere (2.4% neglect; 4.9% extinction) nor after right hemisphere (26.2% neglect; 24.3% extinction) stroke. CONCLUSIONS: Visual extinction seems to be as asymmetrically associated with the human right hemisphere as is spatial neglect.

Evaluation of Yield and Drought Using Active and Passive Spectral Sensing Systems at the Reproductive Stage in Wheat.

Active and passive sensors are available for ground-based, high-throughput phenotyping in the field. However, these sensor systems have seldom been compared with respect to their determination of plant water status and water use efficiency related parameters under drought conditions. In this study, five passive and active reflectance sensors, including a hyperspectral passive sensor, an active flash sensor (AFS), the Crop Circle, and the GreenSeeker, were evaluated to assess drought-related destructive and non-destructive morphophysiological parameters (ground cover, relative leaf water content, leaf temperature, and carbon isotope discrimination of leaves and grain) and grain yield of twenty wheat (Triticum aestivum L.) cultivars. Measurements were conducted in a 2-year study, including a drought stress and a control environment under field conditions. A comparison of the active sensors at the heading, anthesis and grain-filling stages indicated that the Crop Circle provided the most significant and robust relationships with drought-related parameters (relative leaf water content and leaf and grain carbon isotope discrimination). In comparison with the passive sensor, the five water and normalized water indices (WI and NWI-1 to 4), which are only provided by the passive sensor, showed the strongest relationships with the drought stress-related parameters (r = -0.49 to -0.86) and grain yield (r = -0.88) at anthesis. This paper indicates that precision phenotyping allows the integration of water indices in breeding programs to rapidly and cost-effectively identify drought-tolerant genotypes. This is supported by the fact that grain yield and the water indices showed the same heritability under drought conditions.

Vaccination with the polymorphic membrane protein A reduces Chlamydia muridarum induced genital tract pathology.

Chlamydia trachomatis serovars D-K are one of the most frequent causes of sexually transmitted infections of the female genital tract, with possible complications such as hydrosalpinx, pelvic inflammatory disease, extra-uterine gravidity or infertility. We used the murine genital tract infection model with C. muridarum for vaccination studies and found that more than 70% of the infected mice suffered from uterus dilatations and/or hydrosalpinx. Systemic consequences of the vaginal infection were apparent by splenomegaly ten to fifteen days post infection. While cultivable microorganisms were detectable for the first 23days post infection, the first lesions of the genital tract developed at day 15, however, many lesions occurred later in the absence of cultivable bacteria. Lesions were not accompanied by pro-inflammatory cytokines such as IFNÉ£, TNF and IL-6, since these cytokines were almost undetectable in the genital tract 43days post infection. To prevent genital tract lesions, we vaccinated mice with the polymorphic membrane protein (Pmp) A in combination with CpG-ODN 1826 as adjuvant. The vaccine lowered the chlamydial burden and the differences were significant at day 10 post infection but not later. More importantly the vaccine decreased the rate and severity of genital tract lesions. Interestingly, control vaccination with the protein ovalbumin plus CpG-ODN 1826 enhanced significantly the severity but not the rate of pathologic lesions, which was presumably caused by the activation of innate immune responses by the adjuvant in the absence of a C. muridarum-specific adaptive immune response. In summary, vaccination with recombinant PmpA plus CpG-ODN 1826 significantly reduced C. muridarum-induced tissue damage, however, CpG-ODN 1826 may aggravate C. muridarum-induced tissue injuries in the absence of a protective antigen.

A Probiotic Adjuvant Lactobacillus rhamnosus Enhances Specific Immune Responses after Ocular Mucosal Immunization with Chlamydial Polymorphic Membrane Protein C.

Recent advances in the development of chlamydia vaccines, using live-attenuated or ultraviolet light-inactivated chlamydia, are paving the way for new possibilities to oppose the societal challenges posed by chlamydia-related diseases, such as blinding trachoma. An effective subunit vaccine would mitigate the risks associated with the use of a whole-cell vaccine. Our rationale for the design of an efficient subunit vaccine against Chlamydia trachomatis (Ct) is based on the membrane proteins involved in the initial Ct-host cell contact and on the route of immunization that mimics the natural infection process (i.e., via the ocular mucosa). The first aim of our study was to characterize the specific conjunctival and vaginal immune responses following eye drop immunization in BALB/c mice, using the N-terminal portion of the Ct serovar E polymorphic membrane protein C (N-PmpC) as the subunit vaccine antigen. Second, we aimed to examine the adjuvant properties of the probiotic Lactobacillus rhamnosus (LB) when formulated with N-PmpC. N-PmpC applied alone stimulated the production of N-PmpC- and Ct serovar B-specific antibodies in serum, tears and vaginal washes, whereas the combination with LB significantly enhanced these responses. The N-PmpC/LB combination initiated a T cell response characterized by an elevated percentage of CD25+ T cells and CD8+ effector T cells, enhanced CD4+ T-helper 1 skewing, and increased regulatory T cell responses. Together, these results show that eye drop vaccination with combined use of N-PmpC and a live probiotic LB stimulates specific cellular and humoral immune responses, not only locally in the conjunctiva but also in the vaginal mucosa, which could be a promising approach in Ct vaccine development.

OmpA family proteins and Pmp-like autotransporter: new adhesins of Waddlia chondrophila.

Waddlia chondrophila is a obligate intracellular bacterium belonging to the Chlamydiales order, a clade that also includes the well-known classical Chlamydia responsible for a number of severe human and animal diseases. Waddlia is an emerging pathogen associated with adverse pregnancy outcomes in humans and abortion in ruminants. Adhesion to the host cell is an essential prerequisite for survival of every strict intracellular bacteria and, in classical Chlamydia, this step is partially mediated by polymorphic outer membrane proteins (Pmps), a family of highly diverse autotransporters that represent about 15% of the bacterial coding capacity. Waddlia chondrophila genome however only encodes one putative Pmp-like protein. Using a proteomic approach, we identified several bacterial proteins potentially implicated in the adhesion process and we characterized their expression during the replication cycle of the bacteria. In addition, we demonstrated that the Waddlia Pmp-like autotransporter as well as OmpA2 and OmpA3, two members of the extended Waddlia OmpA protein family, exhibit adhesive properties on epithelial cells. We hypothesize that the large diversity of the OmpA protein family is linked to the wide host range of these bacteria that are able to enter and multiply in various host cells ranging from protozoa to mammalian and fish cells.

All subtypes of the Pmp adhesin family are implicated in chlamydial virulence and show species-specific function.

The bacterial pathogens Chlamydia trachomatis and C. pneumoniae are obligate intracellular parasites, cause a number of serious diseases, and can infect various cell types in humans. Chlamydial infections are probably initiated by binding of the bacterial outer membrane protein OmcB to host cell glycosaminoglycans (GAGs). Here, we show that all nine members of the polymorphic membrane protein (Pmp) family of C. trachomatis mediate adhesion to human epithelial and endothelial cells. Importantly, exposure of infectious particles to soluble recombinant Pmps blocks subsequent infection, thus implicating an important function of the entire protein family in the infection process. Analogous experiments with pairs of recombinant Pmps or a combination of Pmp and OmcB revealed that all Pmps probably act in an adhesion pathway that is distinct from the OmcB-GAG pathway. Finally, we provide evidence that the Pmps of C. trachomatis and C. pneumoniae exhibit species and tissue specificity. These findings argue for the involvement of C. trachomatis Pmps in the initial phase of infection and suggest that they may interact with a receptor other than the epidermal growth factor receptor recently identified for their counterparts in C. pneumoniae.

Environmental management of mosquito-borne viruses in Rhode Island.

West Nile Virus (WNV) and Eastern Equine Encephalitis Virus (EEEV) are both primarily bird viruses, which can be transmitted by several mosquito species. Differences in larval habitats, flight, and biting patterns of the primary vector species result in substantial differences in epidemiology, with WNV more common, primarily occurring in urban areas, and EEEV relatively rare, typically occurring near swamp habitats. The complex transmission ecology of these viruses complicates prediction of disease outbreaks. The Rhode Island Department of Environmental Management (DEM) and Department of Health (DoH) provide prevention assistance to towns and maintain a mosquito surveillance program to identify potential disease risk. Responses to potential outbreaks follow a protocol based on surveillance results, assessment of human risk, and technical consultation.

Understanding use of health services in conditional cash transfer programs: insights from qualitative research in Latin America and Turkey.

Conditional cash transfer programs provide cash grants to poor households conditional on their participation in primary health care services. While significant impacts have been demonstrated quantitatively, little attention is paid to why CCTs have these observed impacts, and as importantly- why impacts are not greater than they are. This article draws on qualitative research from four countries over a ten year period (1999-2009) to provide insights into why expected health and nutrition impacts do and do not occur. In Nicaragua, El Salvador, and Turkey, ethnographic methods were used, involving between 87 and 120 households per country, and in Mexico, focus groups were conducted with 230 people. Key informant interviews were conducted with health care providers in all countries. While CCTs operate primarily on the assumption that a cash incentive will produce behaviour change, we found multiple sociocultural and structural influences on health care decisions that compete with cash. These include beliefs around traditional and modern biomedical practices, sociocultural norms, gender relations, and the quotidian experience of poverty in many dimensions. We conclude that impacts can be increased through a better understanding of multiple contextual influences on health care decisions, and greater attention to the health education components and complementary interventions.

Core residue replacements cause coiled-coil orientation switching in vitro and in vivo: structure-function correlations for osmosensory transporter ProP.

Protein ProP acts as an osmosensory transporter in diverse bacteria. C-Terminal residues 468-497 of Escherichia coli ProP (ProPEc) form a four-heptad homodimeric alpha-helical coiled coil. Arg 488, at a core heptad a position, causes it to assume an antiparallel orientation. Arg in the hydrophobic core of coiled coils is destabilizing, but Arg 488 forms stabilizing interstrand salt bridges with Asp 475 and Asp 478. Mutation R488I destabilizes the coiled coil and elevates the osmotic pressure at which ProPEc activates. It may switch the coiled-coil orientation to parallel by eliminating the salt bridges and increasing the hydrophobicity of the core. In this study, mutations D475A and D478A, which disrupt the salt bridges without increasing the hydrophobicity of the coiled-coil core, had the expected modest impacts on the osmotic activation of ProPEc. The five-heptad coiled coil of Agrobacterium tumefaciens ProP (ProPAt) has K498 and R505 at a positions. Mutation K498I had little effect on the osmotic activation of ProPAt, and ProPAt-R505I was activated only at high osmotic pressure; on the other hand, the double mutant was refractory to osmotic activation. Both a synthetic peptide corresponding to ProPAt residues 478-516 and its K498I variant maintained the antiparallel orientation. The single R505I substitution created an unstable coiled coil with little orientation preference. Double mutation K498I/R505I switched the alignment, creating a stable parallel coiled coil. In vivo cross-linking showed that the C-termini of ProPAt and ProPAt-K498I/R505I were antiparallel and parallel, respectively. Thus, the antiparallel orientation of the ProP coiled coil is contingent on Arg in the hydrophobic core and interchain salt bridges. Two key amino acid replacements can convert it to a stable parallel structure, in vitro and in vivo. An intermolecular antiparallel coiled coil, present on only some orthologues, lowers the osmotic pressure required to activate ProP. Formation of a parallel coiled coil renders ProP inactive.

Expression and functional analysis of the anaplastic lymphoma kinase (ALK) gene in tumor cell lines.

The initial identification of the ALK gene, expressed as C-terminal part of the transforming fusion protein NPM-ALK in the t(2;5)(p23;q35) lymphoma-associated chromosomal translocation, revealed a novel receptor tyrosine kinase (RTK). In order to expand the knowledge on ALK expression in the human system, we examined a panel of human cell lines for ALK expression and found that transcription is completely repressed in cell lines of entodermal origin (0/21). Furthermore, full length receptor expression is absent in cell lines of the hematopoietic system with the exception of t(2;5)-associated anaplastic large cell lymphomas lines (ALCL), which are known to express chimeric NPM-ALK mRNA. Cell lines established from solid tumors of ectodermal origin, including melanoma and breast carcinoma, exhibited widespread mRNA expression of the ALK receptor at a broad range (53/64), an association which was found to be strongest in cell lines derived from neuroblastoma (6/6), glioblastoma (8/8) as well as in cell lines established from Ewing sarcoma (4/4) and retinoblastomas (2/2). Because of the reported involvement of neutrophin tyrosine kinase receptors in autocrine differentiation in neuroblastomas, we analyzed cell lines positive for full length or chimeric ALK protein for the presence of phoshotyrosine residues within the intracellular region of ALK. While the constitutive activation of chimeric NPM-ALK molecules could be shown, no evidence was found for induced or constitutively activated ALK receptors in neuroblastoma, melanoma or breast carcinoma cell lines. Although the receptor could be shown to be consistently expressed with exclusive specificity in tissues developed from the ectoderm, our results do not support any involvement of ALK in the stimulation of tumorigenic cell growth or differentiation so far, indicating that ALK expression is a physiologic rather than a pathologic phenomenon.