Impact of Race, Socioeconomic Status, and Geography on Healthcare Outcomes for Children With Sickle Cell Disease in the United States: A Scoping Review.

A large proportion of patients with sickle cell disease (SCD) identify as Black or African American (AA). Social bias and stigma in healthcare outcomes for children with SCD are impossible to explore without considering the impact of racial/cultural identity, socioeconomic status (SES), and geography. It is important to understand the current influences of social movements, expanded health insurance coverage, and telehealth on these variables when considering healthcare outcomes for patients with SCD. The objective of this study was to determine the roles of racial identity, SES, and geography in healthcare outcomes for the pediatric population of children with SCD in the United States (US). This study is a scoping review following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The databases utilized included Cochrane, CINHAL, Medline, and Nursing and Allied Health Collection, all accessed through the EBSCO Information Services. Studies met the following inclusion criteria: published in English, pediatric patients residing in the US, and published between 2017 and 2022. Search terms included "sickle cell" AND "pediatric", which were then combined with "minority" OR "racial" OR "rural" OR "urban" OR "poverty" OR "income" OR "socioeconomic status". The initial search yielded 635 unique articles, with 17 articles meeting full inclusion criteria. Overall, it was clear that there are examples of positive effects of race, low SES, and rural geographic location on positive health outcomes, though a large number of studies oscillated between showing negative associations or no association at all. Barriers to care for patients with SCD are multifaceted, making it difficult to isolate and analyze the impact of individual variables. Many studies demonstrated the significance of family, community, and institutional relationships as positive support for patients with SCD. This review highlights the need for additional research on the healthcare outcome benefits of patient/familial support groups aiming to bring together patients who share racial experience and SCD diagnosis regardless of SES and geography.

Alternative Treatments to Pharmacological Therapy in Pediatric Populations With Attention-Deficit/Hyperactivity Disorder (ADHD): A Scoping Review.

In recent years, there has been an increase in the prevalence of the diagnosis of attention-deficit/hyperactivity disorder (ADHD), a cognitive and behavioral disorder in which individuals present with inattention and impulsivity, in the pediatric population. With an increase in diagnoses, there is also increasing concern regarding overdiagnosis and overtreatment with medications for ADHD. The objective of this study was to map out and compile the recent literature pertaining to alternative therapies (e.g., physical activity, diet, mindfulness, and computer-based interventions) for children and adolescents diagnosed with ADHD in an attempt to reduce or replace the use of pharmacological therapy. This scoping review searched articles from multiple databases (PubMed, ScienceDirect, Web of Science, Directory of Open Access Journals, Scopus, and CINAHL). Using search terms "children with ADHD," "alternative treatment," and "cognitive behavioral therapy," articles were identified that were specific to the research question. The inclusion criteria were patients under the age of 18 with a previous diagnosis of ADHD, no other comorbid illnesses, alternative treatments, and was limited to studies published between 2012 and 2022. After removing duplicates, screening for eligibility criteria, and conducting a critical appraisal of the articles, 16 articles were retained for the final review. The main alternative therapeutic domains that emerged were (1) physical activity, (2) diet, (3) mindfulness, (4) computer-based interventions, and (5) miscellaneous interventions. Seven articles assessed the effect of physical activity on executive and cognitive function in children and adolescents with ADHD. Most findings showed improvement with increased physical activity. Two articles explored the effect of diet on the improvement of ADHD symptoms and reported a positive impact. The two articles that evaluated the effects of mindfulness on ADHD symptoms reported a reduction in ADHD symptoms. Two studies evaluated the use of computer-based interventions as an adjunct treatment in children and adolescents with ADHD; improvements in symptoms were reported. One study each evaluated interventions based on music and nerve stimulation. These showed an improvement in attention, memory, and executive function. With the increasing prevalence of ADHD diagnosis in children and adolescents, alternative and/or adjunctive treatments may be a viable and valuable alternative to pharmaceutical interventions. The findings from this review suggest that multiple non-pharmacological interventions effectively reduce symptoms of ADHD in children and adolescents, including diet, exercise, mindfulness, computer-based interventions, music, and nerve stimulation. While there are implications for alternatives to be used in the future, more research is warranted using larger samples with controlled trials.

Mechanistic study of broadly neutralizing human monoclonal antibodies against dengue virus that target the fusion loop.

There are no available vaccines for dengue, the most important mosquito-transmitted viral disease. Mechanistic studies with anti-dengue virus (DENV) human monoclonal antibodies (hMAbs) provide a rational approach to identify and characterize neutralizing epitopes on DENV structural proteins that can serve to inform vaccine strategies. Here, we report a class of hMAbs that is likely to be an important determinant in the human humoral response to DENV infection. In this study, we identified and characterized three broadly neutralizing anti-DENV hMAbs: 4.8A, D11C, and 1.6D. These antibodies were isolated from three different convalescent patients with distinct histories of DENV infection yet demonstrated remarkable similarities. All three hMAbs recognized the E glycoprotein with high affinity, neutralized all four serotypes of DENV, and mediated antibody-dependent enhancement of infection in Fc receptor-bearing cells at subneutralizing concentrations. The neutralization activities of these hMAbs correlated with a strong inhibition of virus-liposome and intracellular fusion, not virus-cell binding. We mapped epitopes of these antibodies to the highly conserved fusion loop region of E domain II. Mutations at fusion loop residues W101, L107, and/or G109 significantly reduced the binding of the hMAbs to E protein. The results show that hMAbs directed against the highly conserved E protein fusion loop block viral entry downstream of virus-cell binding by inhibiting E protein-mediated fusion. Characterization of hMAbs targeting this region may provide new insights into DENV vaccine and therapeutic strategies.

Release of dengue virus genome induced by a peptide inhibitor.

Dengue virus infects approximately 100 million people annually, but there is no available therapeutic treatment. The mimetic peptide, DN59, consists of residues corresponding to the membrane interacting, amphipathic stem region of the dengue virus envelope (E) glycoprotein. This peptide is inhibitory to all four serotypes of dengue virus, as well as other flaviviruses. Cryo-electron microscopy image reconstruction of dengue virus particles incubated with DN59 showed that the virus particles were largely empty, concurrent with the formation of holes at the five-fold vertices. The release of RNA from the viral particle following incubation with DN59 was confirmed by increased sensitivity of the RNA genome to exogenous RNase and separation of the genome from the E protein in a tartrate density gradient. DN59 interacted strongly with synthetic lipid vesicles and caused membrane disruptions, but was found to be non-toxic to mammalian and insect cells. Thus DN59 inhibits flavivirus infectivity by interacting directly with virus particles resulting in release of the genomic RNA.

Viral entry inhibitors block dengue antibody-dependent enhancement in vitro.

Severe dengue virus (DENV) disease symptoms, including dengue hemorrhagic fever and dengue shock syndrome, have been correlated with the presence of pre-existing antibodies that enhance rather than neutralize infections in Fc receptor bearing cells. These antibodies can originate from previous infection with a different serotype of dengue, or from waning antibody titers that occur in infants and young children as they are weaned from breast milk that contains protective dengue-specific antibodies. Despite the apparent importance of this antibody dependent enhancement (ADE) effect, there has been no description of any specific inhibitors of this process. We explored DENV entry inhibitors as a potential strategy to block ADE. Two different peptide entry inhibitors were tested for the ability to block antibody-mediated DENV-2 infection of human, FcRII bearing K562 cells in vitro. Both peptides were able to inhibit ADE, showing that entry inhibitors are possible candidates for the development of specific treatment for severe DENV infection.

Structural optimization and de novo design of dengue virus entry inhibitory peptides.

Viral fusogenic envelope proteins are important targets for the development of inhibitors of viral entry. We report an approach for the computational design of peptide inhibitors of the dengue 2 virus (DENV-2) envelope (E) protein using high-resolution structural data from a pre-entry dimeric form of the protein. By using predictive strategies together with computational optimization of binding "pseudoenergies", we were able to design multiple peptide sequences that showed low micromolar viral entry inhibitory activity. The two most active peptides, DN57opt and 1OAN1, were designed to displace regions in the domain II hinge, and the first domain I/domain II beta sheet connection, respectively, and show fifty percent inhibitory concentrations of 8 and 7 microM respectively in a focus forming unit assay. The antiviral peptides were shown to interfere with virus:cell binding, interact directly with the E proteins and also cause changes to the viral surface using biolayer interferometry and cryo-electron microscopy, respectively. These peptides may be useful for characterization of intermediate states in the membrane fusion process, investigation of DENV receptor molecules, and as lead compounds for drug discovery.

Neutralizing and non-neutralizing monoclonal antibodies against dengue virus E protein derived from a naturally infected patient.

BACKGROUND: Antibodies produced in response to infection with any of the four serotypes of dengue virus generally provide homotypic immunity. However, prior infection or circulating maternal antibodies can also mediate a non-protective antibody response that can enhance the course of disease in a subsequent heterotypic infection. Naturally occurring human monoclonal antibodies can help us understand the protective and pathogenic roles of the humoral immune system in dengue virus infection. RESULTS: Epstein-Barr Virus (EBV) transformation of B cells isolated from the peripheral blood of a human subject with previous dengue infection was performed. B cell cultures were screened by ELISA for antibodies to dengue (DENV) envelope (E) protein. ELISA positive cultures were cloned by limiting dilution. Three IgG1 human monoclonal antibodies (HMAbs) were purified and their binding specificity to E protein was verified by ELISA and biolayer interferometry. Neutralization and enhancement assays were conducted in epithelial and macrophage-like cell lines, respectively. All three HMAbs bound to E from at least two of the four DENV serotypes, one of the HMAbs was neutralizing, and all were able to enhance DENV infection. CONCLUSIONS: HMAbs against DENV can be successfully generated by EBV transformation of B cells from patients at least two years after naturally acquired DENV infections. These antibodies show different patterns of cross-reactivity, neutralizing, and enhancement activity.

In vitro inhibition of dengue virus entry by p-sulfoxy-cinnamic acid and structurally related combinatorial chemistries.

The anti-adhesive compound p-sulfoxy-cinnamic acid, zosteric acid (ZA), is derived from the temperate marine eelgrass, Zostera marina. ZA and five combinatorial chemistries based on ZA were evaluated for their anti-viral properties against dengue virus in a focus forming unit reduction assay. None of the compounds showed evidence of toxicity to the monkey kidney cell line LLCMK-2 over the concentration ranges tested. ZA showed a modest IC(50) of approximately 2.3 mM against DENV-2. Three other compounds showed IC(50) values of 2.5, 2.4, 0.3 mM, with a fourth not achieving a 50% inhibitory concentration against DENV-2. The most active compound, CF 238, showed IC(50) values of 24, 46, 14 and 47 microM against DENV-1, DENV-2, DENV-3 and DENV-4, respectively. CF 238 showed evidence of inhibition at an entry step in the viral life cycle and enhanced virus:cell binding as evidenced by a quantitative RT-PCR assay system. CF 238 may promote inappropriate virus:cell attachments common to all DENV strains that interfere with receptor interactions required for viral entry. These and other related chemistries may be useful as reagents for studying DENV entry, capturing and detecting DENV, and development of pharmaceuticals.

Viroporin potential of the lentivirus lytic peptide (LLP) domains of the HIV-1 gp41 protein.

BACKGROUND: Mechanisms by which HIV-1 mediates reductions in CD4+ cell levels in infected persons are being intensely investigated, and have broad implications for AIDS drug and vaccine development. Virally induced changes in membrane ionic permeability induced by lytic viruses of many families contribute to cytopathogenesis. HIV-1 induces disturbances in plasma membrane ion transport. The carboxyl terminus of TM (gp41) contains potential amphipathic alpha-helical motifs identified through their structural similarities to naturally occurring cytolytic peptides. These sequences have been dubbed lentiviral lytic peptides (LLP) -1, -2, and -3. RESULTS: Peptides corresponding to the LLP domains (from a clade B virus) partition into lipid membranes, fold into alpha-helices and disrupt model membrane permeability. A peptide corresponding to the LLP-1 domain of a clade D HIV-1 virus, LLP-1D displayed similar activity to the LLP-1 domain of the clade B virus in all assays, despite a lack of amino acid sequence identity. CONCLUSION: These results suggest that the C-terminal domains of HIV-1 Env proteins may form an ion channel, or viroporin. Increased understanding of the function of LLP domains and their role in the viral replication cycle could allow for the development of novel HIV drugs.

Cytopathic mechanisms of HIV-1.

The human immunodeficiency virus type 1 (HIV-1) has been intensely investigated since its discovery in 1983 as the cause of acquired immune deficiency syndrome (AIDS). With relatively few proteins made by the virus, it is able to accomplish many tasks, with each protein serving multiple functions. The Envelope glycoprotein, composed of the two noncovalently linked subunits, SU (surface glycoprotein) and TM (transmembrane glycoprotein) is largely responsible for host cell recognition and entry respectively. While the roles of the N-terminal residues of TM is well established as a fusion pore and anchor for Env into cell membranes, the role of the C-terminus of the protein is not well understood and is fiercely debated. This review gathers information on TM in an attempt to shed some light on the functional regions of this protein.

Human, rhesus macaque, and feline sequences highly similar to mouse mammary tumor virus sequences.

Sequences highly similar (>95%) to the mouse mammary tumor virus (MMTV) env gene have been amplified from human DNA samples, including DNA samples from patients with breast cancer (BC) and persons who did not have BC. The sequences from human DNA were distinct from the MMTV sequences used as controls in these PCR reactions, indicating that these results are not simply due to contamination. In addition to both, mouse and human-related sequences were also amplified from some monkey and cat genomic DNA samples. These products were shown to be distinct from, but highly related to, the MMTV env gene, whereas, testing of other sources (lambda phage, snake, cockroach, sea urchin, chicken, or dog) demonstrated no specific amplification. A sequence 90% similar to the MMTV group antigen gene (gag) was amplified from cat DNA. These results indicate that DNA from vertebrate species other than rodents, including some but not all humans, monkeys, and cats, can contain sequences closely related to MMTV.