ABSTRACT
There is an unmet clinical need for improved tissue and liquid biopsy tools for cancer detection. We investigated the proteomic profile of extracellular vesicles and particles (EVPs) in 426 human samples from tissue explants (TEs), plasma, and other bodily fluids. Among traditional exosome markers, CD9, HSPA8, ALIX, and HSP90AB1 represent pan-EVP markers, while ACTB, MSN, and RAP1B are novel pan-EVP markers. To confirm that EVPs are ideal diagnostic tools, we analyzed proteomes of TE- (n = 151) and plasma-derived (n = 120) EVPs. Comparison of TE EVPs identified proteins (e.g., VCAN, TNC, and THBS2) that distinguish tumors from normal tissues with 90% sensitivity/94% specificity. Machine-learning classification of plasma-derived EVP cargo, including immunoglobulins, revealed 95% sensitivity/90% specificity in detecting cancer. Finally, we defined a panel of tumor-type-specific EVP proteins in TEs and plasma, which can classify tumors of unknown primary origin. Thus, EVP proteins can serve as reliable biomarkers for cancer detection and determining cancer type.
Subject(s)
Biomarkers, Tumor/metabolism , Extracellular Vesicles/metabolism , Neoplasms/diagnosis , Animals , Biomarkers, Tumor/blood , Cell Line , HSC70 Heat-Shock Proteins/metabolism , Humans , Machine Learning , Mice , Mice, Inbred C57BL , Microfilament Proteins/metabolism , Neoplasms/metabolism , Proteome/analysis , Proteome/metabolism , Proteomics/methods , Sensitivity and Specificity , Tetraspanin 29/metabolism , rap GTP-Binding Proteins/metabolismABSTRACT
BACKGROUND: Informal care is a key element of health care and well-being for society, yet it is scarcely visible and rarely studied in health economic evaluations. This study aims to estimate the time use and cost associated with informal care for cardiovascular diseases, pneumonia and ten different cancers in eight Latin American countries (Argentina, Brazil, Chile, Colombia, Costa Rica, Ecuador, Mexico and Peru). METHODS: We carried out an exhaustive literature review on informal caregivers' time use, focusing on the selected diseases. We developed a survey for professional caregivers and conducted expert interviews to validate this data in the local context. We used an indirect estimate through the interpolation of the available data, for those cases in which we do not found reliable information. We used the proxy good method to estimate the monetary value of the use of time of informal care. National household surveys databases were processed to obtain the average wage per hour of a proxy of informal caregiver. Estimates were expressed in 2020 US dollars. RESULTS: The study estimated approximately 1,900 million hours of informal care annually and $ 4,300 million per year in average informal care time cost for these fifteen diseases and eight countries analyzed. Cardiovascular diseases accounted for an informal care burden that ranged from 374 to 555 h per year, while cancers varied from 512 to 1,825 h per year. The informal care time cost share on GDP varied from 0.26% (Mexico) to 1.38% (Brazil), with an average of 0.82% in the studied American countries. Informal care time cost represents between 16 and 44% of the total economic cost (direct medical and informal care cost) associated with health conditions. CONCLUSIONS: The study shows that there is a significant informal care economic burden -frequently overlooked- in different chronic and acute diseases in Latin American countries; and highlights the relevance of including the economic value of informal care in economic evaluations of healthcare.
Subject(s)
Caregivers , Patient Care , Humans , Cardiovascular Diseases/therapy , Caregivers/economics , Latin America , Neoplasms/therapy , Costs and Cost Analysis , Pneumonia/therapy , Patient Care/economics , Patient Care/statistics & numerical data , Time FactorsABSTRACT
BACKGROUND: The prevalence of modern contraception use is higher in Kenya than in most countries in Sub-Saharan Africa. The uptake has however slowed down in recent years, which, among other factors, has been attributed to challenges in the supply chain and increasing stockouts of family planning commodities. Research on the frequency of contraceptive stockouts and its consequences for women in Kenya is still limited and mainly based on facility audits. METHODS: This study employs a set of methods that includes mystery clients, focus group discussions, key informant interviews, and journey mapping workshops. Using this multi-method approach, we aim to quantify the frequency of method denial resulting from contraceptive stockout and describe the impact of stockouts on the lived experiences of women seeking contraception in Western Kenya. RESULTS: Contraceptives were found to be out of stock in 19% of visits made to health facilities by mystery clients, with all contraceptive methods stocked out in 9% of visits. Women experienced stockouts as a sizeable barrier to accessing their preferred method of contraception and a reason for taking up non-preferred methods, which has dire consequences for heath, autonomy, and the ability to prevent unintended pregnancy. Reasons for contraceptive stockouts are many and complex, and often linked to challenges in the supply chain - including inefficient planning, procurement, and distribution of family planning commodities. CONCLUSIONS: Contraceptive stockouts are frequent and negatively impact patients, providers, and communities. Based on the findings of this study, the authors identify areas where funding and sustained action have the potential to ameliorate the frequency and severity of contraceptive stockouts, including more regular deliveries, in-person data collection, and use of data for forecasting, and point to areas where further research is needed.
Subject(s)
Contraception , Contraceptive Agents , Pregnancy , Humans , Female , Kenya , Contraception/methods , Family Planning Services , Pregnancy, Unplanned , Contraception BehaviorABSTRACT
Posttraumatic stress disorder (PTSD) is a risk factor for adolescent suicidal ideation (SI). This study explored the relation between PTSD symptom clusters and SI, and whether social support moderates this association, in a cross-sectional, adolescent, clinical sample (N = 125). We hypothesized that each cluster would be positively associated with SI severity and that social support would buffer these associations. Only the persistent avoidance cluster was significantly associated with SI severity. Further, social support moderated this association. Results highlight the positive association between persistent avoidance symptoms of PTSD and SI and suggest that bolstering social support serves a protective function.
Subject(s)
Stress Disorders, Post-Traumatic , Suicidal Ideation , Adolescent , Cross-Sectional Studies , Humans , Social Support , Stress Disorders, Post-Traumatic/diagnosis , SyndromeABSTRACT
Our objective was to map and prioritize barriers to high-quality family planning care in western Kenya. We conducted key informant interviews (n = 19); focus group discussions with clients (n = 55); mystery client visits (n = 180); unannounced visitors (n = 120); and direct observation of client-provider interactions (n = 256) at public facilities offering family planning. We synthesized the data into a client and a provider journey map, which we used to facilitate client (n = 9) and provider (n = 12) discussions. For both groups, stockouts were frequent, impactful, and important barriers. Clients also reported male partner resistance, insufficient counseling, and informal fees were priority barriers.
ABSTRACT
BACKGROUND: Existing research has predominately focused on dyadic relationships in families of children with intellectual disabilities. The aim of this study was to build on emerging literature exploring triadic relationships between a mother, sibling, and child with intellectual disability, investigating how they influence each other's well-being. METHOD: An online survey was used to collect information regarding the mother's mental health and the emotional and behavioural problems of the sibling and the child with intellectual disability in 573 families. RESULTS: Using structural equation modelling, we found that maternal psychological distress was associated with higher levels of behaviour problems in the sibling, and the behaviour problems of the child with intellectual disability were associated with higher levels of maternal distress. CONCLUSIONS: Family member well-being is inter-related in families of children with intellectual disabilities. Clinical interventions that improve the behaviours of children with intellectual disabilities should be considered.
Subject(s)
Intellectual Disability , Problem Behavior , Child , Female , Humans , Intellectual Disability/psychology , Mothers , Siblings/psychology , Surveys and QuestionnairesABSTRACT
Ever since Stephen Paget's 1889 hypothesis, metastatic organotropism has remained one of cancer's greatest mysteries. Here we demonstrate that exosomes from mouse and human lung-, liver- and brain-tropic tumour cells fuse preferentially with resident cells at their predicted destination, namely lung fibroblasts and epithelial cells, liver Kupffer cells and brain endothelial cells. We show that tumour-derived exosomes uptaken by organ-specific cells prepare the pre-metastatic niche. Treatment with exosomes from lung-tropic models redirected the metastasis of bone-tropic tumour cells. Exosome proteomics revealed distinct integrin expression patterns, in which the exosomal integrins α6ß4 and α6ß1 were associated with lung metastasis, while exosomal integrin αvß5 was linked to liver metastasis. Targeting the integrins α6ß4 and αvß5 decreased exosome uptake, as well as lung and liver metastasis, respectively. We demonstrate that exosome integrin uptake by resident cells activates Src phosphorylation and pro-inflammatory S100 gene expression. Finally, our clinical data indicate that exosomal integrins could be used to predict organ-specific metastasis.
Subject(s)
Brain/metabolism , Exosomes/metabolism , Integrins/metabolism , Liver/metabolism , Lung/metabolism , Neoplasm Metastasis/pathology , Neoplasm Metastasis/prevention & control , Tropism , Animals , Biomarkers/metabolism , Brain/cytology , Cell Line, Tumor , Endothelial Cells/cytology , Endothelial Cells/metabolism , Epithelial Cells/cytology , Epithelial Cells/metabolism , Female , Fibroblasts/cytology , Fibroblasts/metabolism , Genes, src , Humans , Integrin alpha6beta1/metabolism , Integrin alpha6beta4/antagonists & inhibitors , Integrin alpha6beta4/metabolism , Integrin beta Chains/metabolism , Integrin beta4/metabolism , Integrins/antagonists & inhibitors , Kupffer Cells/cytology , Kupffer Cells/metabolism , Liver/cytology , Lung/cytology , Mice , Mice, Inbred C57BL , Organ Specificity , Phosphorylation , Receptors, Vitronectin/antagonists & inhibitors , Receptors, Vitronectin/metabolism , S100 Proteins/geneticsABSTRACT
The lack of a mutant phenotype in homozygous mutant individuals' due to compensatory gene expression triggered upstream of protein function has been identified as genetic compensation. Whilst this intriguing process has been recognized in zebrafish, the presence of homozygous loss of function mutations in healthy human individuals suggests that compensation may not be restricted to this model. Loss of skeletal α-actin results in nemaline myopathy and we have previously shown that the pathological symptoms of the disease and reduction in muscle performance are recapitulated in a zebrafish antisense morpholino knockdown model. Here we reveal that a genetic actc1b mutant exhibits mild muscle defects and is unaffected by injection of the actc1b targeting morpholino. We further show that the milder phenotype results from a compensatory transcriptional upregulation of an actin paralogue providing a novel approach to be explored for the treatment of actin myopathy. Our findings provide further evidence that genetic compensation may influence the penetrance of disease-causing mutations.
Subject(s)
Actins/genetics , Dosage Compensation, Genetic/physiology , Muscle, Skeletal/pathology , Mutation , Myopathies, Nemaline/genetics , Animals , Animals, Genetically Modified , Embryo, Nonmammalian , Gene Expression Regulation, Developmental , Gene Knockdown Techniques , Muscle, Skeletal/metabolism , Myopathies, Nemaline/pathology , Penetrance , Phenotype , Protein Isoforms/genetics , Zebrafish/embryology , Zebrafish/geneticsABSTRACT
Mycoplasma pneumoniae is a cell wall-less bacterial pathogen of the conducting airways, causing bronchitis and atypical or "walking" pneumonia in humans. M. pneumoniae recognizes sialylated and sulfated oligosaccharide receptors to colonize the respiratory tract, but the contribution of the latter is particularly unclear. We used chamber slides coated with sulfatide (3-O-sulfogalactosylceramide) to provide a baseline for M. pneumoniae binding and gliding motility. As expected, M. pneumoniae bound to surfaces coated with sulfatide in a manner that was dependent on sulfatide concentration and incubation temperature and inhibited by competing dextran sulfate. However, mycoplasmas bound to sulfatide exhibited no gliding motility, regardless of receptor density. M. pneumoniae also bound lactose 3'-sulfate ligated to an inert polymer scaffold, and binding was inhibited by competing dextran sulfate. The major adhesin protein P1 mediates adherence to terminal sialic acids linked α-2,3, but P1-specific antibodies that blocked M. pneumoniae hemadsorption (HA) and binding to the sialylated glycoprotein laminin by 95% failed to inhibit mycoplasma binding to sulfatide, suggesting that P1 does not mediate binding to sulfated galactose. Consistent with this conclusion, the M. pneumoniae HA-negative mutant II-3 failed to bind to sialylated receptors but adhered to sulfatide in a temperature-dependent manner.
Subject(s)
Bacterial Adhesion/physiology , Glycoproteins/metabolism , Mycoplasma pneumoniae/pathogenicity , Pneumonia, Mycoplasma/microbiology , Bacterial Proteins/metabolism , Humans , Mycoplasma pneumoniae/metabolismABSTRACT
An amendment to this paper has been published and can be accessed via the original article.
ABSTRACT
BACKGROUND: Adolescents who experience symptoms of borderline personality disorder (BPD) are at high risk for alcohol misuse, yet little is known about why these adolescents drink and what factors heighten or mitigate this risk. The current study explores factors that may impact risk for alcohol misuse among youth with BPD symptoms: using alcohol to self-medicate or to rebel and perceived coping skills. METHOD: A sample of 181 psychiatrically hospitalized adolescents (Mage = 15.04 years, SD = 1.31 years; 71.8% female, 83.4% White) was recruited as part of a larger study from the northeastern United States. Assessments and diagnostic interviews were administered to adolescents. RESULTS: Use of alcohol for self-medication and perceived coping skills, but not using alcohol for rebellion, moderated the relationship between BPD symptoms and alcohol misuse. A significant positive relationship between BPD symptoms and alcohol frequency and/or problems was only found among adolescents who reported lower use of alcohol for self-medication purposes or higher perceived coping skills. CONCLUSIONS: Youth with more BPD symptoms are at high risk for alcohol misuse. Moderation effects for self-medication motives and perceived coping skills were counter to hypotheses; lower levels of self-medication motives contributed to greater alcohol problems, as did higher levels of perceived coping skills. Results suggest the importance of assessing how much youth are drinking or experiencing consequences, as well as why they are using alcohol. It is possible adolescents with more BPD symptoms may be reporting more coping skills, but actually exhibiting the phenomenon of apparent competence (i.e., present as 'in control', but actually experiencing extreme distress and lacking sufficient coping skills); collateral reports of adolescents' coping skills may provide a more objective measure of actual skill level. KEY PRACTITIONER MESSAGE: What is known? Adolescents who experience symptoms of borderline personality disorder (BPD) are at high risk for alcohol misuse, yet little is known about why these adolescents drink and what factors heighten or mitigate this risk. What is new? Adolescents who use alcohol to self-medicate or rebel are at high risk for alcohol problems, regardless of presence of BPD symptoms. Contrary to expectations, higher perceived coping skills strengthened the relation between BPD and alcohol misuse. Apparent competence (i.e., present as 'in control' but lack sufficient skills) may be at play. What is significant for clinical practice? Clinicians are encouraged to assess why adolescents are using alcohol and teach alternative coping strategies when self-medication and/or rebellion is an identified use. Clinicians are encouraged to collect collateral reports of adolescent's coping abilities rather than relying solely on self-report.
Subject(s)
Adaptation, Psychological/physiology , Adolescent Behavior/physiology , Borderline Personality Disorder/physiopathology , Motivation/physiology , Underage Drinking/psychology , Adolescent , Adolescent, Hospitalized/statistics & numerical data , Borderline Personality Disorder/epidemiology , Female , Humans , Male , New England/epidemiology , Risk , Underage Drinking/statistics & numerical dataABSTRACT
Mycoplasma pneumoniae is a common cause of human respiratory tract infections, including bronchitis and atypical pneumonia. M. pneumoniae binds glycoprotein receptors having terminal sialic acid residues via the P1 adhesin protein. Here, we explored the impact of sialic acid presentation on M. pneumoniae adherence and gliding on surfaces coated with sialylated glycoproteins, or chemically functionalized with α-2,3- and α-2,6-sialyllactose ligated individually or in combination to a polymer scaffold in precisely controlled densities. In both models, gliding required a higher receptor density threshold than adherence, and receptor density influenced gliding frequency but not gliding speed. However, very high densities of α-2,3-sialyllactose actually reduced gliding frequency over peak levels observed at lower densities. Both α-2,3- and α-2,6-sialyllactose supported M. pneumoniae adherence, but gliding was only observed on the former. Finally, gliding on α-2,3-sialyllactose was inhibited on surfaces also conjugated with α-2,6-sialyllactose, suggesting that both moieties bind P1 despite the inability of the latter to support gliding. Our results indicate that the nature and density of host receptor moieties profoundly influences M. pneumoniae gliding, which could affect pathogenesis and infection outcome. Furthermore, precise functionalization of polymer scaffolds shows great promise for further analysis of sialic acid presentation and M. pneumoniae adherence and gliding.
Subject(s)
Adhesins, Bacterial/metabolism , Lactose/analogs & derivatives , Movement/physiology , Mycoplasma pneumoniae/metabolism , Sialic Acids/metabolism , Glycoproteins/metabolism , Humans , Lactose/metabolism , N-Acetylneuraminic Acid/metabolism , Pneumonia, Mycoplasma/microbiology , Pneumonia, Mycoplasma/pathologyABSTRACT
This study establishes PYROXD1 variants as a cause of early-onset myopathy and uses biospecimens and cell lines, yeast, and zebrafish models to elucidate the fundamental role of PYROXD1 in skeletal muscle. Exome sequencing identified recessive variants in PYROXD1 in nine probands from five families. Affected individuals presented in infancy or childhood with slowly progressive proximal and distal weakness, facial weakness, nasal speech, swallowing difficulties, and normal to moderately elevated creatine kinase. Distinctive histopathology showed abundant internalized nuclei, myofibrillar disorganization, desmin-positive inclusions, and thickened Z-bands. PYROXD1 is a nuclear-cytoplasmic pyridine nucleotide-disulphide reductase (PNDR). PNDRs are flavoproteins (FAD-binding) and catalyze pyridine-nucleotide-dependent (NAD/NADH) reduction of thiol residues in other proteins. Complementation experiments in yeast lacking glutathione reductase glr1 show that human PYROXD1 has reductase activity that is strongly impaired by the disease-associated missense mutations. Immunolocalization studies in human muscle and zebrafish myofibers demonstrate that PYROXD1 localizes to the nucleus and to striated sarcomeric compartments. Zebrafish with ryroxD1 knock-down recapitulate features of PYROXD1 myopathy with sarcomeric disorganization, myofibrillar aggregates, and marked swimming defect. We characterize variants in the oxidoreductase PYROXD1 as a cause of early-onset myopathy with distinctive histopathology and introduce altered redox regulation as a primary cause of congenital muscle disease.
Subject(s)
Cell Nucleus/genetics , Distal Myopathies/genetics , Genetic Variation , Myopathies, Structural, Congenital/genetics , Oxidoreductases/genetics , Amino Acid Sequence , Animals , COS Cells , Cell Nucleus/metabolism , Chlorocebus aethiops , Cohort Studies , Creatine Kinase/genetics , Creatine Kinase/metabolism , Cytoplasm/metabolism , Distal Myopathies/pathology , ELAV-Like Protein 4/genetics , ELAV-Like Protein 4/metabolism , Female , Flavoproteins/metabolism , Gene Deletion , Genome-Wide Association Study , Glutathione Reductase/genetics , Glutathione Reductase/metabolism , HEK293 Cells , Humans , Male , Muscle, Skeletal/pathology , Mutation, Missense , Myopathies, Structural, Congenital/pathology , Oxidoreductases/metabolism , Pedigree , Protein Conformation , Saccharomyces cerevisiae Proteins/genetics , Saccharomyces cerevisiae Proteins/metabolism , Zebrafish/geneticsABSTRACT
In human α1-antitrypsin deficiency, homozygous carriers of the Z (E324K) mutation in the gene SERPINA1 have insufficient circulating α1-antitrypsin and are predisposed to emphysema. Misfolding and accumulation of the mutant protein in hepatocytes also causes endoplasmic reticulum stress and underpins long-term liver damage. Here, we describe transgenic zebrafish (Danio rerio) expressing the wildtype or the Z mutant form of human α1-antitrypsin in hepatocytes. As observed in afflicted humans, and in rodent models, about 80% less α1-antitrypsin is evident in the circulation of zebrafish expressing the Z mutant. Although these zebrafish also show signs of liver stress, they do not accumulate α1-antitrypsin in hepatocytes. This new zebrafish model will provide useful insights into understanding and treatment of α1-antitrypsin deficiency.
Subject(s)
Hepatocytes/metabolism , Models, Animal , alpha 1-Antitrypsin Deficiency/metabolism , alpha 1-Antitrypsin/metabolism , Animals , CHO Cells , Cell Line , Cricetulus , Humans , Mutation , Zebrafish , alpha 1-Antitrypsin/genetics , alpha 1-Antitrypsin Deficiency/geneticsABSTRACT
Most adolescents do not receive effective mental health services. This may stem in part from infrequent use of evidence-based and multi-informant diagnostic assessments to guide clinical care. The primary purpose of the present study was to examine whether adolescent mental health diagnoses and suicidality, derived via evidence-based diagnostic interviews and assessments, correspond with reported "reason for treatment" received by adolescents. Secondarily, we examined the potential association between socio-economic status and the match between youth diagnoses and reasons for treatment. The influence of parent-adolescent agreement on diagnoses and reasons for treatment on findings was also explored. Using chi-square analyses, a significant association was found between youth diagnoses of mood disorders, disruptive behavior disorders, and suicidality, respectively, and a focus of treatment on these conditions per combined parent-adolescent report. The same was not true for youth anxiety, attention-deficit hyperactivity, or substance abuse disorders. Results of exploratory analyses suggest that these results are driven by adolescent, but not parent report. With regard to socio-economic status, there was a trend for those with higher incomes to report a treatment focus consistent with youth diagnoses, per combined parent-adolescent report. Results suggest that focus of mental health treatment received by adolescents in standard community-based care may not uniformly address all current disorders. Efforts are needed to disseminate multi-informant evidence-based assessments to enhance the quality and effectiveness of care.
ABSTRACT
A major limitation of research on attitudes toward suicide is that most measures lack evidence of a stable factor structure. To investigate the structure of recently developed stigma of suicide scale-short form (SOSS-SF), we conducted an exploratory factor analysis in a sample of 499 undergraduates. Results revealed a three-factor structure: Stigma, Isolation/Depression, and Glorification/Normalization. We also identified good convergent and discriminant validity between the SOSS-SF and related constructs. In a separate sample of 570 undergraduates, a confirmatory factor analysis (CFA) demonstrated adequate fit for the three-factor model. In addition, a multiple-group CFA demonstrated invariance across gender.
Subject(s)
Attitude , Social Stigma , Suicide/psychology , Adult , Factor Analysis, Statistical , Female , Humans , Male , Models, Psychological , Psychometrics , Surveys and Questionnaires , Young AdultABSTRACT
BACKGROUND: Computational identification of non-coding RNAs (ncRNAs) is a challenging problem. We describe a genome-wide analysis using Bayesian segmentation to identify intronic elements highly conserved between three evolutionarily distant vertebrate species: human, mouse and zebrafish. We investigate the extent to which these elements include ncRNAs (or conserved domains of ncRNAs) and regulatory sequences. RESULTS: We identified 655 deeply conserved intronic sequences in a genome-wide analysis. We also performed a pathway-focussed analysis on genes involved in muscle development, detecting 27 intronic elements, of which 22 were not detected in the genome-wide analysis. At least 87% of the genome-wide and 70% of the pathway-focussed elements have existing annotations indicative of conserved RNA secondary structure. The expression of 26 of the pathway-focused elements was examined using RT-PCR, providing confirmation that they include expressed ncRNAs. Consistent with previous studies, these elements are significantly over-represented in the introns of transcription factors. CONCLUSIONS: This study demonstrates a novel, highly effective, Bayesian approach to identifying conserved non-coding sequences. Our results complement previous findings that these sequences are enriched in transcription factors. However, in contrast to previous studies which suggest the majority of conserved sequences are regulatory factor binding sites, the majority of conserved sequences identified using our approach contain evidence of conserved RNA secondary structures, and our laboratory results suggest most are expressed. Functional roles at DNA and RNA levels are not mutually exclusive, and many of our elements possess evidence of both. Moreover, ncRNAs play roles in transcriptional and post-transcriptional regulation, and this may contribute to the over-representation of these elements in introns of transcription factors. We attribute the higher sensitivity of the pathway-focussed analysis compared to the genome-wide analysis to improved alignment quality, suggesting that enhanced genomic alignments may reveal many more conserved intronic sequences.
Subject(s)
Genome , RNA, Untranslated/metabolism , Animals , Bayes Theorem , Binding Sites , Conserved Sequence , Humans , Introns , Mice , Muscle Development/genetics , Nucleic Acid Conformation , RNA, Untranslated/chemistry , RNA, Untranslated/genetics , Transcription Factors/genetics , Transcription Factors/metabolism , User-Computer Interface , Zebrafish/geneticsABSTRACT
In this work, we report a convenient and versatile strategy for surface-grafted glycopolymer constructs with the goal of surface modification that controls the chemical presentation and grafting density of carbohydrate side chains. This approach employs a difunctional hydrazine linker, chemically modified to an active ester containing poly(pentafluorophenyl acrylate) grafted scaffold, to conjugate a variety of saccharides through the reducing end. The successive conjugation steps are carried out under mild conditions and yield high surface densities of sugars, as high as 4.8 nmol·cm-2, capable of multivalency, with an intact structure and retained bioactivity. We also demonstrate that this glycosylated surface can bind specific lectins according to the structure of its pendant carbohydrate. To demonstrate bioactivity, this surface platform is used to study the binding events of a human respiratory tract pathogen, Mycoplasma pneumoniae, on surfaces conjugated with sialylated sugars.
Subject(s)
Carbohydrates/chemistry , Acrylates , Glycosylation , Humans , Lectins , Surface PropertiesABSTRACT
PURPOSE OF REVIEW: The prevalence of feeding disorders in medically complex children is estimated to be as high as 80%. Enteral tube nutrition (ETN) is commonly used for nutritional support in children with feeding disorders. Adverse consequences of ETN include medical complications, psychosocial problems, and higher healthcare costs. We used a retrospective cohort controlled study design to compare outcomes of our outpatient multidisciplinary intensive feeding therapy (IFT) program to our traditional therapy (TT) of single-discipline, once weekly feeding therapy to reduce ETN dependence in medically complex young children. RECENT FINDINGS: Children in the IFT cohort experienced a median reduction in ETN dependence of 49% (34.5-58.5%) compared with a median reduction of 0% (0-25%) for TT (p > 0.0001). Almost half of the IFT cohort no longer required ETN by the conclusion of the 5-week program. Medically complex young children (median age 26 months) successfully reduce or eliminate ETN in an outpatient multidisciplinary intensive feeding program.