Therapeutics Pipeline.

Children have unique physiologic, developmental, and psychosocial needs and unique vulnerabilities, making them a challenging population for which to develop therapeutics. This is particularly apparent in the urgent and chaotic environment of a pandemic or outbreak. Advances in the development of medical countermeasures (MCMs) for pediatric populations have grown substantially over the last decade, and the coronavirus disease 2019 pandemic forced advancements in how we approach pediatric MCM development. Consequently, a MCMs pipeline targeting the pediatric population is essential. This article addresses the challenges inherent in these differences that must be taken into account.

Vaccinations in children with hematologic malignancies and those receiving hematopoietic stem cell transplants or cellular therapies.

Children who are immune compromised are uniquely threatened by a higher risk of infections, including vaccine-preventable diseases (VPDs). Children who undergo chemotherapy or cellular therapies may not have preexisting immunity to VPDs at the time of their treatment including not yet receiving their primary vaccine series, and additionally they have higher risk of exposures (e.g., due to family structures, daycare and school setting) with decreased capacity to protect themselves using nonpharmaceutic measures (e.g., masking). In the past, efforts to revaccinate these children have often been delayed or incomplete. Treatment with chemotherapy, stem cell transplants, and/or cellular therapies impair the ability of the immune system to mount a robust vaccine response. Ideally, protection would be provided as soon as both safe and effective, which will vary by vaccine type (e.g., replicating versus nonreplicating; conjugated versus polysaccharide). While a single approach revaccination schedule following these therapies would be convenient for providers, it would not account for patient specific factors that influence the timing of immune reconstitution (IR). Evidence suggests that many of these children would mount a meaningful vaccine response as early as 3 months following completion of treatment. Here within, we provide updated guidance on how to approach vaccination both during and following completion of these therapies.

Pott's Puffy Tumor in an Inflammatory Bowel Disease Patient on Anti-TNF Therapy.

BACKGROUND Anti-TNF-alpha therapies were the first class of biologics to be used in treatment of moderate to severe IBD. Immunosuppression status that develops from using anti-TNF-a therapies increases the risk of serious and opportunistic infections. We present here a rare case of serious infection that developed in an IBD patient while on anti-TNF therapy. CASE REPORT Our patient was a 14-year-old boy with a history of chronic sinusitis and ulcerative colitis who had been on infliximab therapy for the last 3 years. He presented with facial swelling and worsening constant frontal headache. Imaging showed frontal scalp subgaleal abscess, mild frontal calvarial early osteomyelitis, bilateral preseptal cellulitis, and acute and chronic paranasal sinus disease. He was treated with intravenous antibiotics and underwent sinus surgery with incision and drainage of the forehead abscess. He recovered well and resumed his infliximab infusions 3 weeks after the surgery. CONCLUSIONS PPT is a serious complication of untreated sinusitis. IBD patients on biologics can have higher risk of developing such complications because of their decreased ability to fight infections. Although the risk of serious infections declines significantly after the first year of using biologics, physicians should keep a low threshold for investigating symptomatic patients for serious infections, as they require prompt intervention. Despite the potential complications from using biologics, the benefits of this therapy in IBD patients outweigh the risks.

A Pediatric Infectious Diseases Perspective of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) and Novel Coronavirus Disease 2019 (COVID-19) in Children.

Understanding the role that children play in the clinical burden and propagation of severe acute respiratory syndrome coronavirus 2, responsible for coronavirus disease 2019 (COVID-19) infections, is emerging. While the severe manifestations and acute clinical burden of COVID-19 have largely spared children compared with adults, understanding the epidemiology, clinical presentation, diagnostics, management, and prevention opportunities and the social and behavioral impacts on child health is vital. Foremost is clarifying the contribution of asymptomatic and mild infections to transmission within the household and community and the clinical and epidemiologic significance of uncommon severe post-infectious complications. Here, we summarize the current knowledge, identify resources, and outline research opportunities. Pediatric infectious diseases clinicians have a unique opportunity to advocate for the inclusion of children in epidemiological, clinical, treatment, and prevention studies to optimize their care as well as to represent children in the development of guidance and policy during pandemic response.

Anti-Mayaro virus activity of Cassia australis extracts (Fabaceae, Leguminosae).

BACKGROUND: The arthropod-borne Mayaro virus (MAYV) causes 'Mayaro fever', a disease of medical significance, primarily affecting individuals in permanent contact with forested areas in tropical South America. Studies showed that the virus could also be transmitted by the mosquito Aedes aegypti. Recently, MAYV has attracted attention due to its likely urbanization. To date, there are no drugs that can treat this illness. METHODS: Fractions and compounds were obtained by chromatography from leaf extracts of C. australis and chemically identified as flavonoids and condensed tannins using spectroscopic and spectrometric techniques (UV, NMR, and ESI-FT-ICR MS). Cytotoxicity of EtOAc, n-BuOH and EtOAc-Pp fractions were measured by the dye-uptake assay while their antiviral activity was evaluated by a virus yield inhibition assay. Larvicidal activity was measured by the procedures recommended by the WHO expert committee for determining acute toxicity. RESULTS: The following group of substances was identified from EtOAc, n-BuOH and EtOAc-Pp fractions: flavones, flavonols, and their glycosides and condensed tannins. EtOAc and n-BuOH fractions inhibited MAYV production, respectively, by more than 70% and 85% at 25 µg/mL. EtOAc-Pp fraction inhibited MAYV production by more than 90% at 10 µg/mL, displaying a stronger antiviral effect than the licensed antiviral ribavirin. This fraction had an excellent antiviral effect (IC90 = 4.7 ± 0.3 µg/mL), while EtOAc and n-BuOH fractions were less active (IC90 = 89.1 ± 4.4 µg/mL and IC90 = 40.9 ± 5.7 µg/mL, respectively). CONCLUSIONS: C. australis can be used as a source of compounds with anti-Mayaro virus activity. This is the first report on the biological activity of C. australis.

Secretory cavities and volatiles of Myrrhinium atropurpureum Schott var. atropurpureum (Myrtaceae): an endemic species collected in the restingas of Rio de Janeiro, Brazil.

In this study, we investigated the leaf anatomy and the composition of volatiles in Myrrhinium atropurpureum var. atropurpureum endemic to Rio de Janeiro restingas. Particularly, leaf secretory structures were described using light microscopy, and histochemical tests were performed from fresh leaves to localize the secondary metabolites. To observe secretory cavities, fixed leaf samples were free-hand sectioned. To evaluate lipophilic compounds and terpenoids the following reagents were employed: Sudans III and IV, Red oil O and Nile blue. Leaf volatiles were characterized by gas chromatography after hydrodistillation (HD) or simultaneous distillation-extraction (SDE). Leaf analysis showed several cavities in mesophyll that are the main sites of lipophilic and terpenoid production. Monoterpenes, which represented more than 80% of the major volatiles, were characterized mainly by alpha- and beta-pinene and 1,8-cineole. In order to provide tools for M. atropurpureum identification, the following distinguishing characteristics were revealed by the following data: 1) adaxial face clear and densely punctuated by the presence of round or ellipsoidal secretory cavities randomly distributed in the mesophyll; 2) the presence of cells overlying the upper neck cells of secretory cavities; 3) the presence of numerous paracytic stomata distributed on the abaxial leaf surface, but absent in vein regions and leaf margin; and 4) non-glandular trichomes on both leaf surfaces. Our study of the compounds produced by the secretory cavities of M. atropurpureum led us to conclude that volatile terpenoid class are the main secretory compounds and that they consist of a high concentration of monoterpenes, which may indicate the phytotherapeutic importance of this plant.

Leaf anatomy and morphology of Eugenia rotundifolia Casar., Myrtaceae, applied to the authentication of the "abajurú" commercially sold

Eugenia rotundifolia Casar., Myrtaceae, occurs in the sandy coastal environments of Rio de Janeiro and Espírito Santo States. To the best of our knowledge, E. rotundifolia was not included in ethnobotanical and nor in pharmacological research, but its leaves are sold in a public market of Rio de Janeiro City as "abajurú", the common name for Chrysobalanus icaco L., Chrysobalanaceae. C. icaco, in contrast, has been studied and its medicinal effects reported. Since E. rotundifolia is often sold in the public market as "abajurú," this paper describes and compares the leaf anatomy and morphology of E. rotundifolia with C. icaco, previously described in the literature, in order to provide tools for the authentication of commercialized "abajurú." Phyllotaxy; texture; color; margin; midrib prominence; stomata type; type and shape of midrib and petiole vascular bundle; the presence of marginal vein, secretory cavities, which are seen as translucent dots, and overlying cells only in E. rotundifolia; and the presence of trichomes, periclinal divisions in adaxial face epidermis, hypodermis and vascular bundle extensions only in C. icaco were found to be the most distinguishable diagnostic characters.

Influence of growth regulators in biomass production and volatile profile of in vitro plantlets of Thymus vulgaris L.

In vitro shoots of thyme (Thymus vulgaris L.) were established, and the effects of the auxin indole-3-acetic (IAA) acid and the cytokinins benzyladenine (BA), zeatin (ZEA), and kinetin (KIN) at 1.0, 5.0, and 10.0 microM on rooting, biomass production, and volatile compounds production by these plants were investigated. The volatiles were extracted by solid phase microextraction (SPME) and analyzed by gas chromatography. The highest biomass shoot growth was obtained with BA at 5.0 microM, while IAA at all concentrations tested achieved 100% rooting frequency. The three major compounds were gamma-terpinene (22.8-38.8%), p-cymene (13.8-27.9%), and thymol (6.5-29.0%). Quantitative changes of these compounds were observed in response to the effect of varying growth regulators concentrations in the culture medium. Growing Thymus vulgaris L. plants in media supplemented with IAA at 1.0 microM increased volatile compounds such as thymol by 315%. Nevertheless, the same major compounds were produced in all treatments and no qualitative changes were observed in the volatile profile of thyme plants.

Gr-1+CD115+ immature myeloid suppressor cells mediate the development of tumor-induced T regulatory cells and T-cell anergy in tumor-bearing host.

The accumulation of myeloid suppressor cells (MSCs) is associated with immune suppression in tumor-bearing mice and in cancer patients. The suppressive activity of MSC correlates with the expression of the myeloid markers Gr-1, CD115 (macrophage colony-stimulating factor receptor), and F4/80. Gr-1(+)CD115(+) MSCs, in addition to being able to suppress T-cell proliferation in vitro, can induce the development of Foxp3(+) T regulatory cells (Treg) in vivo, which are anergic and suppressive. Furthermore, the secretion of interleukin (IL)-10 and transforming growth factor-beta by Gr-1(+)CD115(+) MSCs was induced and enhanced, respectively, on IFN-gamma stimulation. The development of Treg requires antigen-associated activation of tumor-specific T cells, depends on the presence of IFN-gamma and IL-10, and is independent of the nitric oxide-mediated suppressive mechanism by MSC. Our data provide evidence that Gr-1(+)CD115(+) MSC can mediate the development of Treg in tumor-bearing mice and show a novel immune suppressive mechanism by which MSCs can suppress antitumor responses.

Developmental effects of additional ultraviolet a radiation, growth regulators and tyrosine in Alternanthera brasiliana (L) Kuntze cultured in vitro

Culturas de tecidos de Alternanthera brasiliana (L.) Kuntze foram tratadas com diferentes reguladores de crescimento (Cinetina e 2,4-D), tirosina e com ultravioleta longo (UV-A; 320 -400 nm) adicional com o intuito de observar seus efeitos no desenvolvimento e produção de pigmentos. Segmentos nodais de plantas crescidas a partir de sementes foram inoculados nos meios de cultura testados e mantidos sob os diferentes tipos de iluminação. Após 8 semanas este material foi utilizado para avaliação da produção de biomassa, clorofilas e betacianinas. O meio de Murashige and Skoog (MS) + cinetina proporcionou plântulas com até 4 brotos/explante. Este meio iluminado com luz branca (tipo luz do dia) foi a combinação mais adequada para micropropagação, pois apresenta maior porcentagem de enraizamento e maior produção de betacianinas. Plântulas crescidas sob iluminação com ultravioleta adicional tiveram diminuídas tanto a produção de biomassa quanto a relação Clor a/ Clor b. A adição de 2,4-D ao meio de cultura resultou na inibição da produção de pigmentos e no crescimento das plântulas.

NK and CD8+ T cell-mediated eradication of poorly immunogenic B16-F10 melanoma by the combined action of IL-12 gene therapy and 4-1BB costimulation.

In previous reports, systemic administration of a stimulatory monoclonal antibody directed against the 4-1BB receptor had no effect on survival or tumor burden in mice inoculated with the poorly immunogenic B16-F10 melanoma. We combined IL-12 gene transfer with 4-1BB costimulation to explore a previously noted cooperative anti-tumor effect against this model tumor. We hypothesize that the innate immune response mediated by IL-12-activated natural killer (NK) cells initiates the activation of the immune system, leading to the priming of T cells, whereas 4-1BB costimulation enhances the function of primed tumor-specific T cells. The effect of the combination therapy on the growth of subcutaneous (s.c.) tumors and pulmonary metastasis was examined. The combination therapy significantly retarded the growth of subcutaneously-inoculated tumors, and 50% of tumor-bearing mice survived with complete tumor regression. In contrast, neither IL-12 gene transfer nor anti-4-1BB antibody administration alone was as effective. Enhanced CTL activity against both B16-F10 tumor cells and TRP-2-pulsed EL4 syngeneic tumor cells was observed in tumor-bearing animals treated with the combination therapy 2 weeks after treatment and, in long-term survivors from this combination therapy, at >120 days. In a pulmonary metastatic model, only the combination therapy generated significant protection against metastasis. In vivo depletion of NK or CD8(+) but not CD4(+) subsets eliminated the protective immunity. Furthermore, NK cell depletion significantly reduced both tumor-specific CTL activity and the number of tumor-specific IFN-gamma-producing cells, suggesting that this synergistic effect requires the participation of both NK and CD8(+) T cells.