Parkinson's Disease: Advances in Treatment and the Syntheses of Various Classes of Pharmaceutical Drug Substances

An overview of Parkinson's disease (PD) prevalence, diagnosis, and currently available treatment options is provided. A comprehensive list of different classes of marketed pharmaceutical drug products and the syntheses of various drug substances are summarized based on published literature.

Lactational and geographical variation in the concentration of six oligosaccharides in Chinese breast milk: a multicenter study over 13 months postpartum

Introduction

Understanding the variations of oligosaccharide in breast milk contribute to better study how human milk oligosaccharides (HMOs) play a role in health-promoting benefits in infants.

Methods

Six abundant HMOs, 2'-fucosyllactose (2'-FL), 3-fucosyllactose (3-FL), Lacto-N-tetraose (LNT), Lacto-N-neotetraose (LNnT), 3'-sialyllactose (3'-SL) and 6'-sialyllactose (6'-SL), in breast milk collected at 0-5 days, 10-15 days, 40-45 days, 200-240 days, and 300-400 days postpartum from six locations across China were analyzed using high-performance anion-exchange chromatography-pulsed amperometric detector.

Results

The concentration of individual HMO fluctuated dynamically during lactational stages. The median ranges of 2'-FL, 3-FL, LNT, LNnT, 3'-SL, and 6'-SL across the five lactational stages were 935-2865 mg/L, 206-1325 mg/L, 300-1473 mg/L, 32-317 mg/L, 106-228 mg/L, and 20-616 mg/L, respectively. The prominent variation was observed in the content of 6'-SL, which demonstrates a pattern of initial increase followed by a subsequent decrease. Among the five lactational stages, the transitional milk has the highest concentration, which was 31 times greater than the concentration in mature milk at 300-400 days postpartum, where the content is the lowest. Geographical location also influenced the content of HMOs. LNT and LNnT were the highest in mature milk of mothers from Lanzhou among the six sites at 40-240 days postpartum. Breast milks were categorized into two groups base on the abundance of 2'-FL (high and low). There was no significant difference in the proportions of high and low 2'-FL phenotypes among the six sites, and the percentages of high and low 2'-FL phenotypes were 79% and 21%, respectively, across all sites in China.

Discussion

This study provided a comprehensive dataset on 6 HMOs concentrations in Chinese breast milk during the extended postpartum period across a wide geographic range and stratified by high and low 2'-FL phenotypes.

Human milk oligosaccharides reduce necrotizing enterocolitis-induced neuroinflammation and cognitive impairment in mice

Necrotizing enterocolitis (NEC) is the leading cause of morbidity and mortality in premature infants. One of the most devastating complications of NEC is the development of NEC-induced brain injury, which manifests as impaired cognition that persists beyond infancy and which represents a proinflammatory activation of the gut-brain axis. Given that oral administration of the human milk oligosaccharides (HMOs) 2'-fucosyllactose (2'-FL) and 6'-sialyslactose (6'-SL) significantly reduced intestinal inflammation in mice, we hypothesized that oral administration of these HMOs would reduce NEC-induced brain injury and sought to determine the mechanisms involved. We now show that the administration of either 2'-FL or 6'-SL significantly attenuated NEC-induced brain injury, reversed myelin loss in the corpus callosum and midbrain of newborn mice, and prevented the impaired cognition observed in mice with NEC-induced brain injury. In seeking to define the mechanisms involved, 2'-FL or 6'-SL administration resulted in a restoration of the blood-brain barrier in newborn mice and also had a direct anti-inflammatory effect on the brain as revealed through the study of brain organoids. Metabolites of 2'-FL were detected in the infant mouse brain by nuclear magnetic resonance (NMR), whereas intact 2'-FL was not. Strikingly, the beneficial effects of 2'-FL or 6'-SL against NEC-induced brain injury required the release of the neurotrophic factor brain-derived neurotrophic factor (BDNF), as mice lacking BDNF were not protected by these HMOs from the development of NEC-induced brain injury. Taken in aggregate, these findings reveal that the HMOs 2'-FL and 6'-SL interrupt the gut-brain inflammatory axis and reduce the risk of NEC-induced brain injury.NEW & NOTEWORTHY This study reveals that the administration of human milk oligosaccharides, which are present in human breast milk, can interfere with the proinflammatory gut-brain axis and prevent neuroinflammation in the setting of necrotizing enterocolitis, a major intestinal disorder seen in premature infants.

Infants Fed Breastmilk or 2'-FL Supplemented Formula Have Similar Systemic Levels of Microbiota-Derived Secondary Bile Acids

Human milk represents an optimal source of nutrition during infancy. Milk also serves as a vehicle for the transfer of growth factors, commensal microbes, and prebiotic compounds to the immature gastrointestinal tract. These immunomodulatory and prebiotic functions of milk are increasingly appreciated as critical factors in the development of the infant gut and its associated microbial community. Advances in infant formula composition have sought to recapitulate some of the prebiotic and immunomodulatory functions of milk through human milk oligosaccharide (HMO) fortification, with the aim of promoting healthy development both within the gastrointestinal tract and systemically. Our objective was to investigate the effects of feeding formulas supplemented with the HMO 2'-fucosyllactose (2'-FL) on serum metabolite levels relative to breastfed infants. A prospective, randomized, double-blinded, controlled study of infant formulas (64.3 kcal/dL) fortified with varying levels of 2'-FL and galactooligosaccharides (GOS) was conducted [0.2 g/L 2'-FL + 2.2 g/L GOS; 1.0 g/L 2'-FL + 1.4 g/L GOS]. Healthy singleton infants age 0-5 days and with birth weight > 2490 g were enrolled (n = 201). Mothers chose to either exclusively formula-feed or breastfeed their infant from birth to 4 months of age. Blood samples were drawn from a subset of infants at 6 weeks of age (n = 35-40 per group). Plasma was evaluated by global metabolic profiling and compared to a breastfed reference group (HM) and a control formula (2.4 g/L GOS). Fortification of control infant formula with the HMO 2'-FL resulted in significant increases in serum metabolites derived from microbial activity in the gastrointestinal tract. Most notably, secondary bile acid production was broadly increased in a dose-dependent manner among infants receiving 2'-FL supplemented formula relative to the control formula. 2'-FL supplementation increased secondary bile acid production to levels associated with breastfeeding. Our data indicate that supplementation of infant formula with 2'-FL supports the production of secondary microbial metabolites at levels comparable to breastfed infants. Thus, dietary supplementation of HMO may have broad implications for the function of the gut microbiome in systemic metabolism. This trial was registered at with the U.S. National library of Medicine as NCT01808105.

Monitoring and responding to emerging infectious diseases in a university setting: A case study using COVID-19

Emerging infection diseases (EIDs) are an increasing threat to global public health, especially when the disease is newly emerging. Institutions of higher education (IHEs) are particularly vulnerable to EIDs because student populations frequently share high-density residences and strongly mix with local and distant populations. In fall 2020, IHEs responded to a novel EID, COVID-19. Here, we describe Quinnipiac University's response to SARS-CoV-2 and evaluate its effectiveness through empirical data and model results. Using an agent-based model to approximate disease dynamics in the student body, the University established a policy of dedensification, universal masking, surveillance testing via a targeted sampling design, and app-based symptom monitoring. After an extended period of low incidence, the infection rate grew through October, likely due to growing incidence rates in the surrounding community. A super-spreader event at the end of October caused a spike in cases in November. Student violations of the University's policies contributed to this event, but lax adherence to state health laws in the community may have also contributed. The model results further suggest that the infection rate was sensitive to the rate of imported infections and was disproportionately impacted by non-residential students, a result supported by the observed data. Collectively, this suggests that campus-community interactions play a major role in campus disease dynamics. Further model results suggest that app-based symptom monitoring may have been an important regulator of the University's incidence, likely because it quarantined infectious students without necessitating test results. Targeted sampling had no substantial advantages over simple random sampling when the model incorporated contact tracing and app-based symptom monitoring but reduced the upper boundary on 90% prediction intervals for cumulative infections when either was removed. Thus, targeted sampling designs for surveillance testing may mitigate worst-case outcomes when other interventions are less effective. The results' implications for future EIDs are discussed.

Human neutrophil IL1β directs intestinal epithelial cell extrusion during Salmonella infection

Infection of the human gut by Salmonella enterica Typhimurium (STM) results in a localized inflammatory disease that is not mimicked in murine infections. To determine mechanisms by which neutrophils, as early responders to bacterial challenge, direct inflammatory programming of human intestinal epithelium, we established a multi-component human intestinal organoid (HIO) model of STM infection. HIOs were micro-injected with STM and seeded with primary human polymorphonuclear leukocytes (PMN-HIOs). PMNs did not significantly alter luminal colonization of Salmonella, but their presence reduced intraepithelial bacterial burden. Adding PMNs to infected HIOs resulted in substantial accumulation of shed TUNEL⁺ epithelial cells that was driven by PMN Caspase-1 activity. Inhibition of Caspases-1, -3 or -4 abrogated epithelial cell death and extrusion in the infected PMN-HIOs but only Caspase-1 inhibition significantly increased bacterial burden in the PMN-HIO epithelium. Thus, PMNs promote cell death in human intestinal epithelial cells through multiple caspases as a protective response to infection. IL-1β was necessary and sufficient to induce cell shedding in the infected HIOs. These data support a critical innate immune function for human neutrophils in amplifying cell death and extrusion of human epithelial cells from the Salmonella-infected intestinal monolayer.

Neutrophils are early responders to Salmonella intestinal infection, but how they influence infection progression and outcome is unknown. Here we use a co-culture model of human intestinal organoids and human primary neutrophils to study the contribution of human neutrophils to Salmonella infection of the intestinal epithelium. We found that neutrophils markedly enhanced epithelial defenses, including enhancing cell extrusion to reduce intraepithelial burden of Salmonella and close association with the epithelium. These findings reveal an early role for neutrophils in the gut in shaping the gut environment to control epithelial infection.

Experiences of adolescent pregnancy among Maasai in Kenya: Implications for prevention

Adolescent fertility rates are high in Kenya and increase the likelihood of maternal and infant morbidity and mortality. The objectives were to (1) explore the prevalence of unintended pregnancy among Maasai adolescent mothers, (2) understand the context in which pregnancy is occurring, and (3) suggest community-based strategies to prevent adolescent pregnancy. In in-depth, individual, qualitative interviews with Maasai females that gave birth during adolescence, pregnancy was unintended in 100% of cases. Our results suggest a desire among this population to prevent pregnancy and the need for contraception. Our recommendations include comprehensive sex education that targets very young adolescents, implementation of mechanisms to strive toward universal primary education, and the provision of resources and skills to adolescents that they need to practice safer sex.

Comparative transcriptional profiling of the early host response to infection by typhoidal and non-typhoidal Salmonella serovars in human intestinal organoids

Salmonella enterica represents over 2500 serovars associated with a wide-ranging spectrum of disease; from self-limiting gastroenteritis to invasive infections caused by non-typhoidal serovars (NTS) and typhoidal serovars, respectively. Host factors strongly influence infection outcome as malnourished or immunocompromised individuals can develop invasive infections from NTS, however, comparative analyses of serovar-specific host responses have been constrained by reliance on limited model systems. Here we used human intestinal organoids (HIOs), a three-dimensional “gut-like” in vitro system derived from human embryonic stem cells, to elucidate similarities and differences in host responses to NTS and typhoidal serovars. HIOs discriminated between the two most prevalent NTS, Salmonella enterica serovar Typhimurium (STM) and Salmonella enterica serovar Enteritidis (SE), and typhoidal serovar Salmonella enterica serovar Typhi (ST) in epithelial cell invasion, replication and transcriptional responses. Pro-inflammatory signaling and cytokine output was reduced in ST-infected HIOs compared to NTS infections, consistent with early stages of NTS and typhoidal diseases. While we predicted that ST would induce a distinct transcriptional profile from the NTS strains, more nuanced expression profiles emerged. Notably, pathways involved in cell cycle, metabolism and mitochondrial functions were downregulated in STM-infected HIOs and upregulated in SE-infected HIOs. These results correlated with suppression of cellular proliferation and induction of host cell death in STM-infected HIOs and in contrast, elevated levels of reactive oxygen species production in SE-infected HIOs. Collectively, these results suggest that the HIO model is well suited to reveal host transcriptional programming specific to infection by individual Salmonella serovars, and that individual NTS may provoke unique host epithelial responses during intestinal stages of infection.

Salmonella enterica is the major causative agent of bacterial infections associated with contaminated food and water. Salmonella enterica consists of over 2500 serovars of which Typhimurium (STM), Enteritidis (SE) and Typhi (ST) are the three major serovars with medical relevance to humans. These serovars elicit distinctive immune responses and cause different diseases in humans, including self-limiting diarrhea, gastroenteritis and typhoid fever. Differences in the human host response to these serovars are likely to be a major contributing factor to distinct disease outcomes but are not well characterized, possibly due to the limitations of human-derived physiological infection models. Distinct from immortalized epithelial cell culture models, human intestinal organoids (HIOs) are three-dimensional structures derived from embryonic stem cells that differentiate into intestinal mesenchymal and epithelial cells, mirroring key organizational aspects of the intestine. In this study, we used HIOs to monitor transcriptional changes during early stages of STM, SE and ST infection. Our comparative analysis showed that HIO inflammatory responses are the dominant response in all infections, but ST infection induces the weakest upregulation of inflammatory mediators relative to the other serovars. In addition, we identified several cellular processes, including cell cycle and mitochondrial functions, that were inversely regulated between STM and SE infection despite these serovars causing similar localized intestinal infection in humans. Our findings reinforce HIOs as an emerging model system to study Salmonella serovar infection and define global host transcriptional response profiles as a foundation for understanding human infection outcomes.

Multifunctional Benefits of Prevalent HMOs: Implications for Infant Health

Breastfeeding is the best source of nutrition during infancy and is associated with a broad range of health benefits. However, there remains a significant and persistent need for innovations in infant formula that will allow infants to access a wider spectrum of benefits available to breastfed infants. The addition of human milk oligosaccharides (HMOs) to infant formulas represents the most significant innovation in infant nutrition in recent years. Although not a direct source of calories in milk, HMOs serve as potent prebiotics, versatile anti-infective agents, and key support for neurocognitive development. Continuing improvements in food science will facilitate production of a wide range of HMO structures in the years to come. In this review, we evaluate the relationship between HMO structure and functional benefits. We propose that infant formula fortification strategies should aim to recapitulate a broad range of benefits to support digestive health, immunity, and cognitive development associated with HMOs in breastmilk. We conclude that acetylated, fucosylated, and sialylated HMOs likely confer important health benefits through multiple complementary mechanisms of action.

Scalable Asymmetric Syntheses of Foslevodopa and Foscarbidopa Drug Substances for the Treatment of Parkinson's Disease

Foslevodopa (FLD, levodopa 4'-monophosphate, 3) and foscarbidopa (FCD, carbidopa 4'-monophosphate, 4) were identified as water-soluble prodrugs of levodopa (LD, 1) and carbidopa (CD, 2), respectively, which are useful for the treatment of Parkinson's disease. Herein, we describe asymmetric syntheses of FLD (3) and FCD (4) drug substances and their manufacture at pilot scale. The synthesis of FLD (3) employs a Horner-Wadsworth-Emmons olefination reaction followed by enantioselective hydrogenation of the double bond as key steps to introduce the α-amino acid moiety with the desired stereochemistry. The synthesis of FCD (4) features a Mizoroki-Heck reaction followed by enantioselective hydrazination to install the quaternary chiral center bearing a hydrazine moiety.

Hair cortisol concentrations among urban and rural-dwelling mother-child dyads, La Romana, Dominican Republic

Hair cortisol concentrations (HCC) were studied in mother-child dyads of La Romana, Dominican Republic (DR), a low-income city, and of the surrounding bateyes, sugarcane plantation villages with inhabitants frequently of Haitian descent. Populations of low socioeconomic status (SES) experience hypothalamic-pituitary-adrenal (HPA) axis dysregulation. Urban communities may be increasingly exposed to stressors such as crime and concentrated poverty whereas rural communities may be devoid of important community resources. As a result, the experience of stress in poverty may differ by place of residence. The goal of this study was to examine differences in HCC among urban and rural-dwelling mother-child dyads in socioeconomically disadvantaged communities surrounding La Romana, DR. Forty-five mother/child dyads were enrolled in La Romana and 45 at several bateyes surrounding La Romana. Mothers were ≥18 years and children were between 7 and 14 years. Mothers self-reported perceived stress and demographic factors. Hair samples were collected from mothers and children, and HCC was assessed using enzyme-linked immunosorbent assays. General linear models examined associations between socioeconomic factors and HCC, and between maternal and child HCC. HCC were measured in 88 maternal and 87 child samples (N = 175). Mothers living in a batey had higher HCC than those living in La Romana (p = 0.001). HCC was positively associated among maternal-child dyads (p = 0.001). Further, Haitian-born mothers as a population who frequently live in a rural batey experienced higher HCC (p = 0.025) that may partially be explained by discriminatory practices in the DR. This research helps to elucidate the impact of urban and rural environmental settings on HCC.Lay summaryThis study focuses on chronic stress, measured by hair cortisol levels, among a low-income population of Dominican and Haitian mother-child pairs who live in urban and rural settings. We found that Haitian-born mothers, who frequently live in a rural batey, had higher hair cortisol levels than Dominican born mothers. Hair cortisol levels between mothers and their children were positively associated. This study addresses the impact of urban and rural environments on the stress response among socioeconomically disadvantaged persons living in an upper middle income country who bear an excessive burden of psychosocial stress.

Induced organoids derived from patients with ulcerative colitis recapitulate colitic reactivity

The pathogenesis of ulcerative colitis (UC), a major type of inflammatory bowel disease, remains unknown. No model exists that adequately recapitulates the complexity of clinical UC. Here, we take advantage of induced pluripotent stem cells (iPSCs) to develop an induced human UC-derived organoid (iHUCO) model and compared it with the induced human normal organoid model (iHNO). Notably, iHUCOs recapitulated histological and functional features of primary colitic tissues, including the absence of acidic mucus secretion and aberrant adherens junctions in the epithelial barrier both in vitro and in vivo. We demonstrate that the CXCL8/CXCR1 axis was overexpressed in iHUCO but not in iHNO. As proof-of-principle, we show that inhibition of CXCL8 receptor by the small-molecule non-competitive inhibitor repertaxin attenuated the progression of UC phenotypes in vitro and in vivo. This patient-derived organoid model, containing both epithelial and stromal compartments, will generate new insights into the underlying pathogenesis of UC while offering opportunities to tailor interventions to the individual patient.

The Lumen of Human Intestinal Organoids Poses Greater Stress to Bacteria Compared to the Germ-Free Mouse Intestine: Escherichia coli Deficient in RpoS as a Colonization Probe

Pluripotent stem-cell-derived human intestinal organoids (HIOs) are three-dimensional, multicellular structures that model a naive intestinal epithelium in an in vitro system. Several published reports have investigated the use of HIOs to study host-microbe interactions. We recently demonstrated that microinjection of the nonpathogenic Escherichia coli strain ECOR2 into HIOs induced morphological and functional maturation of the HIO epithelium, including increased secretion of mucins and cationic antimicrobial peptides. In the current work, we use ECOR2 as a biological probe to further characterize the environment present in the HIO lumen. We generated an isogenic mutant in the general stress response sigma factor RpoS and employed this mutant to compare challenges faced by a bacterium during colonization of the HIO lumen relative to the germ-free mouse intestine. We demonstrate that the loss of RpoS significantly decreases the ability of ECOR2 to colonize HIOs, although it does not prevent colonization of germ-free mice. These results indicate that the HIO lumen is a more restrictive environment to E. coli than the germ-free mouse intestine, thus increasing our understanding of the HIO model system as it pertains to studying the establishment of intestinal host-microbe symbioses.IMPORTANCE Technological advancements have driven and will continue to drive the adoption of organotypic systems for investigating host-microbe interactions within the human intestinal ecosystem. Using E. coli deficient in the RpoS-mediated general stress response, we demonstrate that the type or severity of microbial stressors within the HIO lumen is more restrictive than those of the in vivo environment of the germ-free mouse gut. This study provides important insight into the nature of the HIO microenvironment from a microbiological standpoint.

Knowledge and misconceptions surrounding family planning among Young Maasai women in Kenya

Adolescent fertility rates are high in Kenya and increase the likelihood of maternal and infant morbidity and mortality. Our objective was to explore the knowledge, perceptions, and barriers surrounding the use of family planning services among young Maasai women in Laikipia County, Central Kenya. Individual interviews with 50 participants were conducted in Laikipia County, Kenya during June and July of 2019. Qualitative data was visualised using JMP software and coded using the framework method for content analysis. Several overarching themes were identified. First, we identified a high rate of unintended pregnancy and a low rate of family planning use. Second, we found that many young Maasai women believe that only women that are married and have finished childbearing should utilise family planning services. Finally, we document highly prevalent myths among young women in the Maasai community that the use of family planning will lead to negative health consequences, such as infertility and cancer. We conclude that the Maasai community of Laikipia County, Kenya needs comprehensive family planning education that will improve knowledge and dispel myths in order to empower young Maasai women to make informed decisions surrounding family planning.

Generation of small intestinal organoids for experimental intestinal physiology

Human intestinal organoids (HIOs) derived from pluripotent stem cells were first described almost a decade ago as a method to differentiate intestinal tissue containing both epithelium and supporting mesenchymal cells. The original protocol documents a directed differentiation approach to first induce definitive endoderm from pluripotent stem cells, followed by hindgut specification, resulting in the self-organization of 3D hindgut spheroids. These hindgut spheroids are then embedded in a basement membrane extracellular matrix (ECM) such as Matrigel and mature into HIOs over about 4 weeks in culture. Since the initial HIO protocol was published, the methods to generate HIOs have been updated over time including revisions to the directed differentiation protocol and implementation of new culture methods for spheroids such as embedding in alginate or polyethylene glycol hydrogels as defined alternatives to Matrigel. Additionally, HIOs have been utilized for new applications such as co-culture with bacteria. This protocol compiles the most up to date information on HIO generation and presents alternative experimental applications.

Microbial Metabolite Signaling Is Required for Systemic Iron Homeostasis

Iron is a central micronutrient needed by all living organisms. Competition for iron in the intestinal tract is essential for the maintenance of indigenous microbial populations and for host health. How symbiotic relationships between hosts and native microbes persist during times of iron limitation is unclear. Here, we demonstrate that indigenous bacteria possess an iron-dependent mechanism that inhibits host iron transport and storage. Using a high-throughput screen of microbial metabolites, we found that gut microbiota produce metabolites that suppress hypoxia-inducible factor 2α (HIF-2α) a master transcription factor of intestinal iron absorption and increase the iron-storage protein ferritin, resulting in decreased intestinal iron absorption by the host. We identified 1,3-diaminopropane (DAP) and reuterin as inhibitors of HIF-2α via inhibition of heterodimerization. DAP and reuterin effectively ameliorated systemic iron overload. This work provides evidence of intestine-microbiota metabolic crosstalk that is essential for systemic iron homeostasis.

Beginning reading interventions for children and adolescents with intellectual disability

BACKGROUND

Historically, students with intellectual disability were not expected to learn to read, and thus were excluded from reading instruction. Over the past decades, societal expectations for this group of learners have changed in that children and adolescents with intellectual disability are now expected to be provided with, and benefit from, literacy instruction. This shift in societal expectations has also led to an increase in research examining effective interventions for increasing beginning reading skills for students with intellectual disability.

OBJECTIVES

To assess the effectiveness of interventions for teaching beginning reading skills to children and adolescents with intellectual disability.

SEARCH METHODS

We searched the following electronic databases up to October 2019: CENTRAL; MEDLINE, including Epub Ahead of Print and In-Process and Other Non-Indexed Citations, Embase, 13 other databases, and two trials registers. We contacted authors of included studies, examined reference lists, and used Google Scholar to search for additional studies.

SELECTION CRITERIA

We included randomized controlled trials (including trials that use quasi-random methods of allocation such as date of birth), involving children and adolescents with intellectual disability (defined as an intelligence quotient (IQ) two standard deviations or more below the population mean) between the ages of 4 and 21 years, that evaluated the efficacy of a beginning reading intervention compared to a control intervention, including no treatment control, wait-list control, treatment as usual, attention control, or alternate non-reading instruction control.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened titles and abstracts yielded by the search against the inclusion criteria, and extracted data from each trial using a piloted data extraction form to collect information about the population, intervention, randomization methods, blinding, sample size, outcome measures, follow-up duration, attrition and handling of missing data, and methods of analysis. When data were missing, one review author contacted the study authors to request additional information. Two review authors assessed the risk of bias of each included study and rated the quality of the evidence using the GRADE approach (a systematic method for rating the certainty of evidence in meta-analyses). We conducted random-effect meta-analyses, with inverse-variance weighting to combine effect sizes for each of our primary and secondary outcomes. We presented effect sizes as standardized mean differences (SMD) with 95% confidence intervals (CI).

MAIN RESULTS

We identified seven studies involving 352 children and adolescents with intellectual disabilities that met the inclusion criteria. All studies provided the intervention in school settings. Four studies were conducted in the USA, one in Canada, and two in the UK. Three studies were funded by grants from the US Department of Education, Institute of Education Sciences; one study by the Canadian Language and Literacy Research Network and the Nova Scotia Health Research Foundation; and three studies did not indicate a funding source. We identified some concerns with risk of bias, mainly due to the difficulty of blinding of participants and personnel, and the lack of blinding of outcome assessors. Meta-analyses of the data demonstrated small-to-moderate effects of beginning reading interventions delivered to children and adolescents with intellectual disability across four dependent variables. We found medium effect sizes in favor of the beginning reading interventions for the primary outcomes of phonologic awareness (SMD 0.55, 95% CI 0.23 to 0.86; 4 studies, 178 participants; moderate-quality evidence), word reading (SMD 0.54, 95% CI 0.05 to 1.03; 5 studies, 220 participants; moderate-quality evidence), and decoding (SMD 0.40, 95% CI 0.12 to 0.67; 5 studies, 230 participants; low-quality evidence). The studies reported no adverse events. We also found a moderate effect for the secondary outcomes of oral reading fluency (SMD 0.65, 95% CI -0.12 to 1.42; 2 studies, 84 participants; low-quality evidence) and language skills (SMD 0.28, 95% CI 0.03 to 0.54; 3 studies, 222 participants; moderate-quality evidence).

AUTHORS' CONCLUSIONS

Results from this review provide evidence that beginning reading interventions that include elements of phonologic awareness, letter sound instruction, and decoding, delivered to children and adolescents with intellectual disability, are associated with small-to-moderate improvements in phonologic awareness, word reading, decoding, expressive and receptive language, and oral reading fluency. These findings are aligned with previously conducted studies that examined the effects of reading interventions for people without intellectual disability.

Astrovirus replication in human intestinal enteroids reveals multi-cellular tropism and an intricate host innate immune landscape

Human astroviruses (HAstV) are understudied positive-strand RNA viruses that cause gastroenteritis mostly in children and the elderly. Three clades of astroviruses, classic, MLB-type and VA-type have been reported in humans. One limitation towards a better understanding of these viruses has been the lack of a physiologically relevant cell culture model that supports growth of all clades of HAstV. Herein, we demonstrate infection of HAstV strains belonging to all three clades in epithelium-only human intestinal enteroids (HIE) isolated from biopsy-derived intestinal crypts. A detailed investigation of infection of VA1, a member of the non-canonical HAstV-VA/HMO clade, showed robust replication in HIE derived from different patients and from different intestinal regions independent of the cellular differentiation status. Flow cytometry and immunofluorescence analysis revealed that VA1 infects several cell types, including intestinal progenitor cells and mature enterocytes, in HIE cultures. RNA profiling of VA1-infected HIE uncovered that the host response to infection is dominated by interferon (IFN)-mediated innate immune responses. A comparison of the antiviral host response in non-transformed HIE and transformed human colon carcinoma Caco-2 cells highlighted significant differences between these cells, including an increased magnitude of the response in HIE. Additional studies confirmed the sensitivity of VA1 to exogenous IFNs, and indicated that the endogenous IFN response of HIE to curtail the growth of strains from all three clades. Genotypic variation in the permissiveness of different HIE lines to HAstV could be overcome by pharmacologic inhibition of JAK/STAT signaling. Collectively, our data identify HIE as a universal infection model for HAstV and an improved model of the intestinal epithelium to investigate enteric virus-host interactions.

Human astroviruses (HAstV) are understudied positive-strand RNA viruses that typically cause gastroenteritis mostly in children and the elderly, but more recent studies also implicate them in neurological disease in immunocompromised patients. To better understand these viruses, a physiologically relevant cell culture model that supports growth of all clades of HAstV would be highly beneficial. Herein, we demonstrated robust infection of HAstV strains belonging to all three clades in epithelium-only human intestinal enteroids (HIE) isolated from biopsy-derived intestinal crypts from different patients and intestinal regions, making HIE a valuable model to study HAstV biology. Using this system, we identify for the first time that VA1 infects several cell types, including intestinal progenitor cells and mature enterocytes. Analysis of the antiviral host response to infection demonstrated that HIE respond to infection with a type I and III interferon response. This response reduced HAstV replication and when blocked resulted in increased infection. Establishment of the HIE system for HAstV research lays the foundation for future basic and translational discoveries.

Generation of lung organoids from human pluripotent stem cells in vitro

The lung epithelium is derived from the endodermal germ layer, which undergoes a complex series of endoderm-mesoderm-mediated signaling events to generate the final arborized network of conducting airways (bronchi, bronchioles) and gas-exchanging units (alveoli). These stages include endoderm induction, anterior-posterior and dorsal-ventral patterning, lung specification, lung budding, branching morphogenesis, and, finally, maturation. Here we describe a protocol that recapitulates several of these milestones in order to differentiate human pluripotent stem cells (hPSCs) into ventral-anterior foregut spheroids and further into two distinct types of organoids: human lung organoids and bud tip progenitor organoids. The resulting human lung organoids possess cell types and structures that resemble the bronchi/bronchioles of the developing human airway surrounded by lung mesenchyme and cells expressing alveolar-cell markers. The bud tip progenitor organoids possess a population of highly proliferative multipotent cells with in vitro multilineage differentiation potential and in vivo engraftment potential. Human lung organoids can be generated from hPSCs in 50-85 d, and bud tip progenitor organoids can be generated in 22 d. The two hPSC-derived models presented here have been benchmarked with human fetal tissue and found to be representative of human fetal-like tissue. The bud tip progenitor organoids are thus ideal for exploring epithelial fate decisions, while the human lung organoids can be used to model epithelial-mesenchymal cross-talk during human lung development. In addition to their applications in developmental biology, human lung organoids and bud tip progenitor organoids may be implemented in regenerative medicine, tissue engineering, and pharmaceutical safety and efficacy testing.

Identification, isolation and characterization of human LGR5-positive colon adenoma cells

The intestine is maintained by stem cells located at the base of crypts and distinguished by the expression of LGR5. Genetically engineered mouse models have provided a wealth of information about intestinal stem cells, whereas less is known about human intestinal stem cells owing to difficulty detecting and isolating these cells. We established an organoid repository from patient-derived adenomas, adenocarcinomas and normal colon, which we analyzed for variants in 71 colorectal cancer (CRC)-associated genes. Normal and neoplastic colon tissue organoids were analyzed by immunohistochemistry and fluorescent-activated cell sorting for LGR5. LGR5-positive cells were isolated from four adenoma organoid lines and were subjected to RNA sequencing. We found that LGR5 expression in the epithelium and stroma was associated with tumor stage, and by integrating functional experiments with LGR5-sorted cell RNA sequencing data from adenoma and normal organoids, we found correlations between LGR5 and CRC-specific genes, including dickkopf WNT signaling pathway inhibitor 4 (DKK4) and SPARC-related modular calcium binding 2 (SMOC2). Collectively, this work provides resources, methods and new markers to isolate and study stem cells in human tissue homeostasis and carcinogenesis.

Real-time Measurement of Epithelial Barrier Permeability in Human Intestinal Organoids

Advances in 3D culture of intestinal tissues obtained through biopsy or generated from pluripotent stem cells via directed differentiation, have resulted in sophisticated in vitro models of the intestinal mucosa. Leveraging these emerging model systems will require adaptation of tools and techniques developed for 2D culture systems and animals. Here, we describe a technique for measuring epithelial barrier permeability in human intestinal organoids in real-time. This is accomplished by microinjection of fluorescently-labeled dextran and imaging on an inverted microscope fitted with epifluorescent filters. Real-time measurement of the barrier permeability in intestinal organoids facilitates the generation of high-resolution temporal data in human intestinal epithelial tissue, although this technique can also be applied to fixed timepoint imaging approaches. This protocol is readily adaptable for the measurement of epithelial barrier permeability following exposure to pharmacologic agents, bacterial products or toxins, or live microorganisms. With minor modifications, this protocol can also serve as a general primer on microinjection of intestinal organoids and users may choose to supplement this protocol with additional or alternative downstream applications following microinjection.

Bacterial colonization stimulates a complex physiological response in the immature human intestinal epithelium

The human gastrointestinal tract is immature at birth, yet must adapt to dramatic changes such as oral nutrition and microbial colonization. The confluence of these factors can lead to severe inflammatory disease in premature infants; however, investigating complex environment-host interactions is difficult due to limited access to immature human tissue. Here, we demonstrate that the epithelium of human pluripotent stem-cell-derived human intestinal organoids is globally similar to the immature human epithelium and we utilize HIOs to investigate complex host-microbe interactions in this naive epithelium. Our findings demonstrate that the immature epithelium is intrinsically capable of establishing a stable host-microbe symbiosis. Microbial colonization leads to complex contact and hypoxia driven responses resulting in increased antimicrobial peptide production, maturation of the mucus layer, and improved barrier function. These studies lay the groundwork for an improved mechanistic understanding of how colonization influences development of the immature human intestine.

Gastrointestinal Organoids: Understanding the Molecular Basis of the Host-Microbe Interface

In recent years, increasing attention has been devoted to the concept that microorganisms play an integral role in human physiology and pathophysiology. Despite this, the molecular basis of host-pathogen and host-symbiont interactions in the human intestine remains poorly understood owing to the limited availability of human tissue, and the biological complexity of host-microbe interactions. Over the past decade, technological advances have enabled long-term culture of organotypic intestinal tissue derived from human subjects and from human pluripotent stem cells, and these in vitro culture systems already have shown the potential to inform our understanding significantly of host-microbe interactions. Gastrointestinal organoids represent a substantial advance in structural and functional complexity over traditional in vitro cell culture models of the human gastrointestinal epithelium while retaining much of the genetic and molecular tractability that makes in vitro experimentation so appealing. The opportunity to model epithelial barrier dynamics, cellular differentiation, and proliferation more accurately in specific intestinal segments and in tissue containing a proportional representation of the diverse epithelial subtypes found in the native gut greatly enhances the translational potential of organotypic gastrointestinal culture systems. By using these tools, researchers have uncovered novel aspects of host-pathogen and host-symbiont interactions with the intestinal epithelium. Application of these tools promises to reveal new insights into the pathogenesis of infectious disease, inflammation, cancer, and the role of microorganisms in intestinal development. This review summarizes research on the use of gastrointestinal organoids as a model of the host-microbe interface.

Morphogenesis and maturation of the embryonic and postnatal intestine

The intestine is a vital organ responsible for nutrient absorption, bile and waste excretion, and a major site of host immunity. In order to keep up with daily demands, the intestine has evolved a mechanism to expand the absorptive surface area by undergoing a morphogenetic process to generate finger-like units called villi. These villi house specialized cell types critical for both absorbing nutrients from food, and for protecting the host from commensal and pathogenic microbes present in the adult gut. In this review, we will discuss mechanisms that coordinate intestinal development, growth, and maturation of the small intestine, starting from the formation of the early gut tube, through villus morphogenesis and into early postnatal life when the intestine must adapt to the acquisition of nutrients through food intake, and to interactions with microbes.

Application of Transcerebral, Weak (1 Microt) Complex Magnetic Fields and Mystical Experiences: Are They Generated by Field-Induced Dimethyltryptamine Release from the Pineal Organ?

During the last 15 years weak, complex magnetic fields have been applied across the two cerebral hemispheres at the level of the temporoparietal lobes of more than 500 volunteers. Most of these subjects have reported visual, vestibular, and proprioceptive sensations as well as experiences of detachment from the body of ‘sentient beings’. Similar but more intense experiences were reported by Strassman in 2001 for volunteers who were injected with N,n-dimethyltryptamine, a compound Strassman hypothesized as the primary mediator of these experiences. If this speculation is valid, then subjects who are exposed to the very weak, complex fields known to elicit similar experiences should display significant increases in the metabolites of this compound within their blood.

LGR4 and LGR5 Function Redundantly During Human Endoderm Differentiation

BACKGROUND & AIMS

The Lgr family of transmembrane proteins (Lgr4, 5, 6) act as functional receptors for R-spondin proteins (Rspo 1, 2, 3, 4), and potentiate Wnt signaling in different contexts. Lgr5 is arguably the best characterized of the Lgr family members in a number of adult and embryonic contexts in mice. However, the function of LGR family members in early embryonic development is unclear, and has not been explored during human development or tissue differentiation in detail.

METHODS

We interrogated the function and expression of LGR family members using human pluripotent stem cell-derived tissues including definitive endoderm, mid/hindgut, and intestinal organoids. We performed embryonic lineage tracing in Lgr5-GFP-IRES-CreERT2 mice.

RESULTS

We show that LGR5 is part of the human definitive endoderm (DE) gene signature, and LGR5 transcripts are induced robustly when human pluripotent stem cells are differentiated into DE. Our results show that LGR4 and 5 are functionally required for efficient human endoderm induction. Consistent with data in human DE, we observe Lgr5 reporter (eGFP) activity in the embryonic day 8.5 mouse endoderm, and show the ability to lineage trace these cells into the adult intestine. However, gene expression data also suggest that there are human-mouse species-specific differences at later time points of embryonic development.

CONCLUSIONS

Our results show that LGR5 is induced during DE differentiation, LGR receptors are functionally required for DE induction, and that they function to potentiate WNT signaling during this process.

Clinical applications of bioactive milk components

Milk represents a unique resource for translational medicine: It contains a rich pool of biologically active molecules with demonstrated clinical benefits. The ongoing characterization of the mechanistic process through which milk components promote development and immunity has revealed numerous milk-derived compounds with potential applications as clinical therapies in infectious and inflammatory disease, cancer, and other conditions. Lactoferrin is an effective antimicrobial and antiviral agent in high-risk patient populations and a potentially potent adjuvant to chemotherapy in lung cancer. Enteric nutrition formulas supplemented with transforming growth factor β, a milk cytokine, have been shown to promote remission in pediatric Crohn's disease. A number of milk glycans, including human milk oligosaccharides, show promise in preclinical studies as antimicrobial and anti-inflammatory agents. While active preclinical investigations of human milk may soon result in large-scale production of human milk molecules, bovine milk components in many instances represent a practical source of bioactive milk compounds for use in clinical trials. This review summarizes current efforts to translate the compounds derived from human and bovine milk into effective clinical therapies. These efforts suggest a common pathway for the translation of milk-derived compounds into clinical applications.

The human milk oligosaccharide 2'-fucosyllactose modulates CD14 expression in human enterocytes, thereby attenuating LPS-induced inflammation

BACKGROUND

A major cause of enteric infection, Gram-negative pathogenic bacteria activate mucosal inflammation through lipopolysaccharide (LPS) binding to intestinal toll-like receptor 4 (TLR4). Breast feeding lowers risk of disease, and human milk modulates inflammation.

OBJECTIVE

This study tested whether human milk oligosaccharides (HMOSs) influence pathogenic Escherichia coli-induced interleukin (IL)-8 release by intestinal epithelial cells (IECs), identified specific proinflammatory signalling molecules modulated by HMOSs, specified the active HMOS and determined its mechanism of action.

METHODS

Models of inflammation were IECs invaded by type 1 pili enterotoxigenic E. coli (ETEC) in vitro: T84 modelled mature, and H4 modelled immature IECs. LPS-induced signalling molecules co-varying with IL-8 release in the presence or absence of HMOSs were identified. Knockdown and overexpression verified signalling mediators. The oligosaccharide responsible for altered signalling was identified.

RESULTS

HMOSs attenuated LPS-dependent induction of IL-8 caused by ETEC, uropathogenic E. coli, and adherent-invasive E. coli (AIEC) infection, and suppressed CD14 transcription and translation. CD14 knockdown recapitulated HMOS-induced attenuation. Overexpression of CD14 increased the inflammatory response to ETEC and sensitivity to inhibition by HMOSs. 2'-fucosyllactose (2'-FL), at milk concentrations, displayed equivalent ability as total HMOSs to suppress CD14 expression, and protected AIEC-infected mice.

CONCLUSIONS

HMOSs and 2'-FL directly inhibit LPS-mediated inflammation during ETEC invasion of T84 and H4 IECs through attenuation of CD14 induction. CD14 expression mediates LPS-TLR4 stimulation of portions of the 'macrophage migration inhibitory factors' inflammatory pathway via suppressors of cytokine signalling 2/signal transducer and activator of transcription 3/NF-κB. HMOS direct inhibition of inflammation supports its functioning as an innate immune system whereby the mother protects her vulnerable neonate through her milk. 2'-FL, a principal HMOS, quenches inflammatory signalling.

Early grade curriculum-based reading measures for students with intellectual disability

The purpose of this study was to extend previous research on the use of curriculum-based measurement (CBM) for students with intellectual disability by having 19 special education teachers monitor weekly reading progress of 38 students with intellectual disability for approximately 15 weeks and examining whether students exhibited gains on the progress monitoring measures. In addition to the weekly CBM, teachers reported the type and duration of daily reading instruction. Data were analyzed to explore relationships between CBM performance and reading instruction. Our results indicate that teachers are capable of administering and scoring CBM on a weekly basis and that CBM does capture reading growth for some students with intellectual disability. Correlations between CBM performance and a teacher report of skills taught during reading instruction indicate that teachers may be differentiating instruction based on students' reading ability. Directions for future research as well as limitations of the study are discussed.

Pasteurized Donor Human Milk Maintains Microbiological Purity for 4 Days at 4°C

BACKGROUND

Most protective components in human milk are stable during prolonged storage at 4ºC; however, pasteurization reduces some microbicidal activities responsible for suppressing microbial growth and protecting against infection. Donor milk used by neonatal intensive care units (NICUs) is frozen pasteurized donor human milk (PDHM) defrosted and stored at 4ºC. Current Human Milk Banking Association of North America (HMBANA) Best Practice guidelines recommend that milk be discarded 24 hours after being thawed, but experimental data on the duration of microbiological purity in thawed PDHM are sparse.

OBJECTIVE

This study evaluates microbiological purity of thawed PDHM during prolonged storage at 4ºC.

METHODS

A total of 42 independent, randomly selected PDHM samples were thawed at 4ºC. As is typical in NICUs, each bottle was opened at 3-hour intervals and 3 mL was withdrawn with a sterile syringe and transferred into a sterile tube. The 3 mL samples removed at 0, 24, 48, 72, 96 hours, and 9 days were tested for the presence of any microorganisms by a clinical laboratory that routinely screens PDHM for microbes.

RESULTS

No evidence of microbial growth was observed in cultured samples taken at 0 to 9 days after thawing of the milk samples.

CONCLUSION

There was no evidence of microbes in PDHM as dispensed by HMBANA milk banks when defrosted and stored at 4ºC for up to 9 days. Extended storage of PDHM in the NICU could reduce waste of donor milk, thereby increasing availability of human milk to vulnerable neonatal patients.

Transcriptome-wide Analysis Reveals Hallmarks of Human Intestine Development and Maturation In Vitro and In Vivo

Human intestinal organoids (HIOs) are a tissue culture model in which small intestine-like tissue is generated from pluripotent stem cells. By carrying out unsupervised hierarchical clustering of RNA-sequencing data, we demonstrate that HIOs most closely resemble human fetal intestine. We observed that genes involved in digestive tract development are enriched in both fetal intestine and HIOs compared to adult tissue, whereas genes related to digestive function and Paneth cell host defense are expressed at higher levels in adult intestine. Our study also revealed that the intestinal stem cell marker OLFM4 is expressed at very low levels in fetal intestine and in HIOs, but is robust in adult crypts. We validated our findings using in vivo transplantation to show that HIOs become more adult-like after transplantation. Our study emphasizes important maturation events that occur in the intestine during human development and demonstrates that HIOs can be used to model fetal-to-adult maturation.

In vitro generation of human pluripotent stem cell derived lung organoids

Recent breakthroughs in 3-dimensional (3D) organoid cultures for many organ systems have led to new physiologically complex in vitro models to study human development and disease. Here, we report the step-wise differentiation of human pluripotent stem cells (hPSCs) (embryonic and induced) into lung organoids. By manipulating developmental signaling pathways hPSCs generate ventral-anterior foregut spheroids, which are then expanded into human lung organoids (HLOs). HLOs consist of epithelial and mesenchymal compartments of the lung, organized with structural features similar to the native lung. HLOs possess upper airway-like epithelium with basal cells and immature ciliated cells surrounded by smooth muscle and myofibroblasts as well as an alveolar-like domain with appropriate cell types. Using RNA-sequencing, we show that HLOs are remarkably similar to human fetal lung based on global transcriptional profiles, suggesting that HLOs are an excellent model to study human lung development, maturation and disease.

Traveler's diarrhea: a clinical review

IMPORTANCE

Acute diarrhea is the most common illness that affects travelers to low-income regions of the world. Although improved hygiene has reduced the risk of traveler's diarrhea in many destinations, the risk remains high in others.

OBJECTIVE

To review the current state of knowledge on the etiology, risk factors, prevention, and management of traveler's diarrhea.

EVIDENCE REVIEW

A search of the PubMed, Google Scholar, and Cochrane Library databases for the period 2012-April 2014 was performed for articles on traveler's diarrhea. The database search yielded 2976 articles, of which 37 were included in this review. These were added to 85 articles previously identified by the authors.

FINDINGS

Improved hygiene has reduced the risk of traveler's diarrhea from 20% or more (for a 2-week stay) to between 8% and 20% in some parts of the world. Acquiring traveler's diarrhea causes 12% to 46% of travelers to change their travel plans. Returning travelers seeking medical care have a diagnosis of gastrointestinal disturbance in approximately one-third of all cases. Postinfectious irritable bowel syndrome may occur in 3% to 17% of patients who have had traveler's diarrhea. Prevention of traveler's diarrhea by dietary avoidance measures is often not successful. Chemoprophylaxis should be restricted to travelers who are at risk of severe complications of diarrhea. Ciprofloxacin is the standard treatment in self-therapy of traveler's diarrhea except when patients are in South or Southeast Asia, where azithromycin is preferred.

CONCLUSIONS AND RELEVANCE

Diarrhea remains a common problem for international travelers. Persons intending to travel to at-risk countries should be counseled regarding prevention measures and may be given a travel pack that includes medications for self-treatment should they become ill.

Vaccine-preventable travel health risks: what is the evidence--what are the gaps?

BACKGROUND

Existing travel health guidelines are based on a variety of data with underpinning evidence ranging from high-quality randomized controlled trials to best estimates from expert opinion. For strategic guidance and to set overall priorities, data about average risk are useful. The World Health Organization (WHO) plans to base future editions of "International Travel and Health" on its new "Handbook for Guideline Development."

METHODS

Based on a systematic search in PubMed, the existing evidence and quality of data on vaccine-preventable disease (VPD) risks in travelers was examined and essentials of vaccine efficacy were briefly reviewed. The Grading of Recommendations, Assessment, Development and Evaluation (GRADE) framework was used to evaluate the quality of the data.

RESULTS

Moderate-quality data to determine the risk of VPD exist on those that are frequently imported, whereas in most others the level of confidence with existing data is low or very low.

CONCLUSIONS

In order for the WHO to produce graded risk statements in the updated version of "International Travel and Health," major investment of time plus additional high-quality, generalizable risk data are needed.

The Maoist insurgency (1996-2006) and child health indicators in Nepal

The association of conflict and child health indicators in Nepal was examined for the period of the Communist Party of Nepal-Maoist (CPN-Maoist) insurgency (1996-2006). National and subregional trends in neonatal protection against tetanus, measles and diphtheria-pertussis-tetanus (DPT) vaccine coverage, infant mortality, under-5 mortality, and proportion of underweight or stunted children were examined. During the period of the insurgency there were overall improvements in vaccination coverage; however, measles vaccine and DPT coverage remained static during several years of conflict. A decline in infant and under-5 mortality rates occurred: however, there were smaller improvements in stunting and underweight children. Improvements in health indicators from the Mid-western Hill subregion of the country, an area that was consistently conflict-affected, were less than those achieved nationally or by the less-affected Eastern Hill subregion. In comparison with Bangladesh and India, improvements in Nepal were the same or better, except for stunting and underweight children. Health interventions that are more easily delivered, such as vaccination, showed improvements, although the changes were less in a region of high conflict. Improvements in child nutrition indicators that necessitate multiple, coordinated interventions and access to at-risk populations over time as well as ongoing food security were not as successful. Continued commitment to development of systems for delivery of child health is important to gain improvements across all childhood health indicators.

Human milk hyaluronan enhances innate defense of the intestinal epithelium

Breast-feeding is associated with enhanced protection from gastrointestinal disease in infants, mediated in part by an array of bioactive glycan components in milk that act through molecular mechanisms to inhibit enteric pathogen infection. Human milk contains hyaluronan (HA), a glycosaminoglycan polymer found in virtually all mammalian tissues. We have shown that synthetic HA of a specific size range promotes expression of antimicrobial peptides in intestinal epithelium. We hypothesize that hyaluronan from human milk also enhances innate antimicrobial defense. Here we define the concentration of HA in human milk during the first 6 months postpartum. Importantly, HA isolated from milk has a biological function. Treatment of HT-29 colonic epithelial cells with human milk HA at physiologic concentrations results in time- and dose-dependent induction of the antimicrobial peptide human β-defensin 2 and is abrogated by digestion of milk HA with a specific hyaluronidase. Milk HA induction of human β-defensin 2 expression is also reduced in the presence of a CD44-blocking antibody and is associated with a specific increase in ERK1/2 phosphorylation, suggesting a role for the HA receptor CD44. Furthermore, oral administration of human milk-derived HA to adult, wild-type mice results in induction of the murine Hβ D2 ortholog in intestinal mucosa and is dependent upon both TLR4 and CD44 in vivo. Finally, treatment of cultured colonic epithelial cells with human milk HA enhances resistance to infection by the enteric pathogen Salmonella typhimurium. Together, our observations suggest that maternally provided HA stimulates protective antimicrobial defense in the newborn.

Students With Autism, Service Dogs, and Public Schools

Children with autism spectrum disorder (ASD) increasingly receive assistance from service dogs. Nonetheless, confusion surrounding service dogs for students with ASD has precipitated litigation between parents and schools. The purpose of this review was to examine state laws pertaining to the use of service dogs among children with ASD. Statutes were evaluated to identify all disability classifications eligible to use a service dog, regulations related to the authorized training of service animals, and school access for service animals. Results suggest that current state laws do not facilitate the use of service dogs by children with ASD or provide sufficient guidance for parents and schools. Recommendations for policy follow a discussion of the results.

Teaching global public health in the undergraduate liberal arts: a survey of 50 colleges

Undergraduate public health and global health studies are usually found at universities with graduate programs in the disciplines. Following the experience of teaching a short course in global health within the liberal arts, we reviewed global and public health offerings at 50 liberal arts colleges for the 2009-2010 academic year. Forty-two percent had a track, concentration, or program, and 30% had global or public health student organizations. All colleges listed at least one course in the fields, with the highest number in the social sciences. However, many colleges had not coordinated them into a theme. Values of a liberal arts education are found in the study of global and public health: social responsibility, critical thinking, ethical reasoning, and knowledge of the wider world. We propose identifying these programs within the undergraduate liberal arts as global public health. Capturing interest in global public health will enhance the curriculum and student experience.In this day and age, when the world is so fluid with regard to news and information, the knowledge that unnecessary deaths are occurring and that health care lags so far behind in some regions cannot be ignored. From the standpoint of basic human rights, suffering and inequity cannot be tolerated. Williams College student during a global health short course.

Specific-sized hyaluronan fragments promote expression of human β-defensin 2 in intestinal epithelium

Hyaluronan (HA) is a glycosaminoglycan polymer found in the extracellular matrix of virtually all mammalian tissues. Recent work has suggested a role for small, fragmented HA polymers in initiating innate defense responses in immune cells, endothelium, and epidermis through interaction with innate molecular pattern recognition receptors, such as TLR4. Despite these advances, little is known regarding the effect of fragmented HA at the intestinal epithelium, where numerous pattern recognition receptors act as sentinels of an innate defense response that maintains epithelial barrier integrity in the presence of abundant and diverse microbial challenges. Here we report that HA fragments promote expression of the innate antimicrobial peptide human β-defensin 2 (HβD2) in intestinal epithelial cells. Treatment of HT-29 colonic epithelial cells with HA fragment preparations resulted in time- and dose-dependent up-regulated expression of HβD2 protein in a fragment size-specific manner, with 35-kDa HA fragment preparations emerging as the most potent inducers of intracellular HβD2. Furthermore, oral administration of specific-sized HA fragments promotes the expression of an HβD2 ortholog in the colonic epithelium of both wild-type and CD44-deficient mice but not in TLR4-deficient mice. Together, our observations suggest that a highly size-specific, TLR4-dependent, innate defense response to fragmented HA contributes to intestinal epithelium barrier defense through the induction of intracellular HβD2 protein.