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1.
Proc Natl Acad Sci U S A ; 121(6): e2317756121, 2024 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-38300868

RESUMEN

Fibroblast growth factor receptor (FGFR) kinase inhibitors have been shown to be effective in the treatment of intrahepatic cholangiocarcinoma and other advanced solid tumors harboring FGFR2 alterations, but the toxicity of these drugs frequently leads to dose reduction or interruption of treatment such that maximum efficacy cannot be achieved. The most common adverse effects are hyperphosphatemia caused by FGFR1 inhibition and diarrhea due to FGFR4 inhibition, as current therapies are not selective among the FGFRs. Designing selective inhibitors has proved difficult with conventional approaches because the orthosteric sites of FGFR family members are observed to be highly similar in X-ray structures. In this study, aided by analysis of protein dynamics, we designed a selective, covalent FGFR2 inhibitor. In a key initial step, analysis of long-timescale molecular dynamics simulations of the FGFR1 and FGFR2 kinase domains allowed us to identify differential motion in their P-loops, which are located adjacent to the orthosteric site. Using this insight, we were able to design orthosteric binders that selectively and covalently engage the P-loop of FGFR2. Our drug discovery efforts culminated in the development of lirafugratinib (RLY-4008), a covalent inhibitor of FGFR2 that shows substantial selectivity over FGFR1 (~250-fold) and FGFR4 (~5,000-fold) in vitro, causes tumor regression in multiple FGFR2-altered human xenograft models, and was recently demonstrated to be efficacious in the clinic at doses that do not induce clinically significant hyperphosphatemia or diarrhea.


Asunto(s)
Neoplasias de los Conductos Biliares , Colangiocarcinoma , Hiperfosfatemia , Humanos , Receptor Tipo 2 de Factor de Crecimiento de Fibroblastos/genética , Receptor Tipo 2 de Factor de Crecimiento de Fibroblastos/química , Conductos Biliares Intrahepáticos/metabolismo , Diarrea , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/química
2.
Microbiology (Reading) ; 170(7)2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38967642

RESUMEN

Artificial intelligence has revolutionized the field of protein structure prediction. However, with more powerful and complex software being developed, it is accessibility and ease of use rather than capability that is quickly becoming a limiting factor to end users. LazyAF is a Google Colaboratory-based pipeline which integrates the existing ColabFold BATCH software to streamline the process of medium-scale protein-protein interaction prediction. LazyAF was used to predict the interactome of the 76 proteins encoded on the broad-host-range multi-drug resistance plasmid RK2, demonstrating the ease and accessibility the pipeline provides.


Asunto(s)
Biología Computacional , Mapeo de Interacción de Proteínas , Programas Informáticos , Biología Computacional/métodos , Simulación por Computador , Plásmidos/genética , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/química , Unión Proteica
3.
Pediatr Blood Cancer ; 71(3): e30779, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38073018

RESUMEN

BACKGROUND AND OBJECTIVES: Kaposiform hemangioendothelioma (KHE) and tufted angioma (TA) are rare vascular tumors in children historically associated with significant morbidity and mortality. This study was conducted to determine first-line therapy in the absence of available prospective clinical trials. METHODS: Patients from 17 institutions diagnosed with KHE/TA between 2005 and 2020 with more than 6 months of follow-up were included. Response rates to sirolimus and vincristine were compared at 3 and 6 months. Durability of response and response to other treatment modalities were also evaluated. RESULTS: Of 159 unique KHE/TA subjects, Kasabach-Merritt phenomenon (KMP) was present in 64 (40.3%), and only two patients were deceased (1.3%). Over 60% (n = 96) demonstrated treatment response at 3 months, and more than 70% (n = 114) by 6 months (no significant difference across groups). The vincristine group had higher radiologic response at 3 months compared to sirolimus (72.7% vs. 20%, p = .03), but there were no differences between these groups at 6 months. There were no differences in rates of recurrent or progressive disease between vincristine and sirolimus. CONCLUSIONS: In this large, multicenter cohort of 159 patients with KHE/TA, rates of KMP were consistent with historical literature, but the mortality rate (1.3%) was much lower. Overall treatment response rates were high (>70%), and there was no significant difference in treatment response or durability of disease comparing sirolimus to vincristine. Our results support individualized treatment decision plans depending on clinical scenario and patient/physician preferences. Response criteria and response rates reported here will be useful for guiding future treatment protocols for vascular tumors.


Asunto(s)
Hemangioendotelioma , Hemangioma , Síndrome de Kasabach-Merritt , Sarcoma de Kaposi , Neoplasias Cutáneas , Neoplasias Vasculares , Niño , Humanos , Síndrome de Kasabach-Merritt/tratamiento farmacológico , Síndrome de Kasabach-Merritt/patología , Vincristina , Estudios Prospectivos , Hemangioendotelioma/tratamiento farmacológico , Hemangioendotelioma/patología , Sarcoma de Kaposi/patología , Sirolimus/uso terapéutico
4.
Microbiology (Reading) ; 169(7)2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37418299

RESUMEN

CutRS was the first two-component system to be identified in Streptomyces species and is highly conserved in this genus. It was reported >25 years ago that deletion of cutRS increases the production of the antibiotic actinorhodin in Streptomyces coelicolor. However, despite this early work, the function of CutRS has remained enigmatic until now. Here we show that deletion of cutRS upregulates the production of the actinorhodin biosynthetic enzymes up to 300-fold, explaining the increase in actinorhodin production. However, while ChIP-seq identified 85 CutR binding sites in S. coelicolor none of these are in the actinorhodin biosynthetic gene cluster, meaning the effect is indirect. The directly regulated CutR targets identified in this study are implicated in extracellular protein folding, including two of the four highly conserved HtrA-family foldases: HtrA3 and HtrB, and a putative VKOR enzyme, which is predicted to recycle DsbA following its catalysis of disulphide bond formation in secreted proteins. Thus, we tentatively propose a role for CutRS in sensing and responding to protein misfolding outside the cell. Since actinorhodin can oxidise cysteine residues and induce disulphide bond formation in proteins, its over production in the ∆cutRS mutant may be a response to protein misfolding on the extracellular face of the membrane.


Asunto(s)
Streptomyces coelicolor , Streptomyces , Streptomyces coelicolor/genética , Streptomyces coelicolor/metabolismo , Factores de Transcripción/genética , Streptomyces/metabolismo , Antibacterianos/farmacología , Disulfuros/metabolismo , Regulación Bacteriana de la Expresión Génica
5.
Pediatr Blood Cancer ; 70(5): e29989, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36726177

RESUMEN

BACKGROUND: Posttherapy imaging studies can provide reassurance or induce anxiety regarding risk of recurrence for patients and their families. In some cases, it is difficult to determine if imaging findings represent posttreatment changes or residual disease. Equivocal radiographic findings can occur due to therapy-related inflammation or residual, inactive soft tissue masses, but it is unknown if such findings indicate an increased likelihood of local recurrence. The aim of this study was to assess the value of initial posttherapy scans for predicting local relapse in patients with Ewing sarcoma (EWS) or rhabdomyosarcoma (RMS) who received radiotherapy (RT) for local control. These findings are critical to inform clinicians' surveillance recommendations and ability to accurately counsel patients and their families. PROCEDURE: The primary endpoint was time to local progression (LP). Patients were classified as having posttherapy scans that were "positive" (residual disease within the RT field), "negative" (no evidence of residual disease within the RT field), or "equivocal" (no determination could be made). The value of initial posttreatment scans for predicting LP was assessed using positive predictive value (PPV) and negative predictive value (NPV). RESULTS: Negative imaging findings (n = 51) had an NPV of 88%, and positive imaging findings (n = 1) had a PPV of 100%. When equivocal findings (n = 16) were categorized with negative results (i.e., positive vs. equivocal/negative), the NPV was 90%. When equivocal findings were categorized with positive results (equivocal/positive vs. negative), the PPV was 12%. CONCLUSION: Equivocal findings within the RT field on end-of-therapy imaging studies indicate no higher risk of local recurrence than negative findings. These results may contribute to appropriate surveillance schedules and accurate counseling of patients with RMS and EWS who have received RT for local control.


Asunto(s)
Leucemia Mieloide Aguda , Rabdomiosarcoma , Sarcoma de Ewing , Sarcoma , Niño , Humanos , Sarcoma de Ewing/diagnóstico por imagen , Sarcoma de Ewing/radioterapia , Recurrencia Local de Neoplasia/diagnóstico por imagen , Rabdomiosarcoma/diagnóstico por imagen , Rabdomiosarcoma/radioterapia , Ansiedad , Estudios Retrospectivos
6.
J Pediatr Hematol Oncol ; 45(8): 452-460, 2023 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-37749794

RESUMEN

Infantile hemangioma (IH) is the most common benign tumor of infancy. For children with IH who require treatment, propranolol and other beta blockers have been shown to be safe and effective. Although consensus guidelines for managing IH have been published, anecdotal experience suggests that there remain variations in management. This study was performed to document these variations amongst providers and to identify areas for future research. We conducted an Internet-based survey of clinicians who treat patients with IH. Hypothetical cases and management scenarios were presented. Twenty-nine respondents participated in the survey. Most respondents use generic propranolol in infants with growing IH of the head and neck, with a goal dose of 2 mg/kg/d, until ~1 year of age. A variety of management strategies were documented including which patients should be treated, optimal dose and duration of therapy, how patients should be monitored, which patients should get additional workup, how propranolol should best be discontinued, and how often to see patients in follow-up. This study demonstrates wide practice variations in managing patients with IH. Further research is indicated to address these variations and develop additional/updated evidence-based guidelines.


Asunto(s)
Hemangioma , Neoplasias Cutáneas , Lactante , Niño , Humanos , Propranolol/uso terapéutico , Hemangioma/tratamiento farmacológico , Resultado del Tratamiento , Neoplasias Cutáneas/patología , Antagonistas Adrenérgicos beta/uso terapéutico
7.
J Pediatr Hematol Oncol ; 44(2): 31-39, 2022 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-34966091

RESUMEN

Infantile hemangiomas (IHs) are common vascular lesions which are benign but can cause significant functional and cosmetic morbidity. Since the fortuitous discovery of propranolol being effective to treat IH over a decade ago, the therapy and prognosis for children with IH have improved dramatically. Oral propranolol (as well as other oral beta-blockers and topical timolol) are safe and effective treatments, and have now supplanted other therapies. Making the correct diagnosis is crucial, because other vascular lesions can mimic IH. In addition, IH can be the first manifestation of an underlying syndrome. For IH requiring treatment, initiating treatment early is key to optimizing success. Therefore, early recognition and referral, if necessary, are important. Continued research on IH, both basic science and clinical, should result in continued advances.


Asunto(s)
Hemangioma , Neoplasias Cutáneas , Antagonistas Adrenérgicos beta/uso terapéutico , Niño , Hemangioma/diagnóstico , Hemangioma/tratamiento farmacológico , Humanos , Lactante , Propranolol/uso terapéutico , Neoplasias Cutáneas/diagnóstico , Timolol/uso terapéutico , Resultado del Tratamiento
8.
J Pediatr Hematol Oncol ; 44(3): e649-e652, 2022 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-34224515

RESUMEN

The severe acute respiratory syndrome coronavirus (SARS-CoV-2) pandemic has disrupted normal health care utilization patterns worldwide, including decreasing emergency department (ED) visits for various medical emergencies. We examined whether this pattern was present in febrile pediatric oncology patients. In this single-center cohort study, we conducted a retrospective chart review of ED visits of febrile pediatric oncology patients during the first 4 months of the global SARS-CoV-2 pandemic and compared those data to the same time periods in the previous 2 years. During the first 5 months of the pandemic, 25 pediatric oncology patients with fever visited our ED; 65 children visited during the same time period in 2018; and 60 visited in 2019. Compared with 2018 and 2019, encounters for 2020 were decreased by 62% and 58%, respectively. A significantly higher percentage of febrile pediatric oncology patients (84%) were admitted to our hospital during the pandemic compared the previous years (58%). Of concern is the possibility that fear of exposure to coronavirus disease-19 (COVID-19) at our health care facility prompted caregivers of pediatric oncology patients to avoid seeking care for their child with fever. Consistent communication with families about the life-threatening nature of fever should be prioritized among pediatric oncology providers.


Asunto(s)
COVID-19 , Neoplasias , COVID-19/epidemiología , Niño , Estudios de Cohortes , Servicio de Urgencia en Hospital , Humanos , Neoplasias/complicaciones , Neoplasias/terapia , Aceptación de la Atención de Salud , Estudios Retrospectivos , SARS-CoV-2
9.
J Pediatr Hematol Oncol ; 44(1): e213-e216, 2022 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-33885035

RESUMEN

Deep sedation/general anesthesia is commonly used in pediatric oncology patients undergoing lumbar puncture (LP). Propofol is often used for sedation, with or without a narcotic. We hypothesized that eutectic mixture of lidocaine and prilocaine (EMLA) would allow for lower cumulative doses of propofol and less movement. We performed a prospective, randomized, double blind, placebo-controlled trial in children undergoing sedation for LP. Standard initial weight-based doses of propofol and fentanyl were administered, with either EMLA cream or a placebo cream applied topically. The primary outcome was the total dose of propofol administered to each patient. We also tracked patient movement and complications. Twenty-seven patients underwent 152 LPs. Patients randomized to EMLA cream (n=75) were significantly more likely to receive a lower dose of propofol (2.94 mg/kg, SE=0.25, vs. 3.22 mg/kg, SE=0.19; P=0.036) and to not require additional propofol doses (probability 0.49, SE=0.08 vs. 0.69, SE=0.06; P=0.001) compared with patients randomized to placebo cream (n=77). In addition, patients with EMLA cream were significantly less likely to demonstrate minor or major movement. EMLA cream results in less movement and less propofol administration in pediatric oncology patients undergoing sedation for LP.


Asunto(s)
Sedación Profunda , Lidocaína/administración & dosificación , Prilocaína/administración & dosificación , Punción Espinal , Adolescente , Niño , Método Doble Ciego , Femenino , Humanos , Lidocaína/efectos adversos , Masculino , Prilocaína/efectos adversos , Propofol/administración & dosificación , Propofol/efectos adversos , Estudios Prospectivos
10.
Pediatr Dermatol ; 39(3): 389-393, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35243678

RESUMEN

BACKGROUND/OBJECTIVES: Propranolol is used to treat problematic infantile hemangiomas (IHs), but its safety in infants <5 weeks corrected age has not been established. The objective of this study was to assess the safety and efficacy of propranolol for treatment of IH in infants <5 weeks corrected age, or 45 weeks corrected gestational age (CGA). METHODS: We performed a single institution, retrospective review of patients treated with propranolol prior to the age of 6 months between 2017 and 2021. Patient characteristics, location of hemangioma(s), weight at initiation of treatment, dosing information, side effects, response, and duration of treatment were documented. RESULTS: Of 200 patients with IH treated with propranolol, 24 started treatment prior to 45 weeks CGA. Mean CGA at initiation of treatment was 42 weeks. Sixty-seven percent were female and 75% were white, non-Hispanic. Mean duration of treatment was 255 days. Twenty-two patients (92%) had clear benefit from treatment at a dose of 1-3 mg/kg/day. The most common side effects were sleep disturbance (21%), irritability (17%), and cool hands/feet (13%). There were no serious adverse events. CONCLUSIONS: In this cohort of 24 patients with corrected age <5 weeks (CGA <45 weeks), propranolol was safe and effective for the treatment of infantile hemangiomas. Larger, prospective studies are indicated to investigate propranolol in this age group.


Asunto(s)
Hemangioma Capilar , Hemangioma , Neoplasias Cutáneas , Administración Oral , Antagonistas Adrenérgicos beta/efectos adversos , Preescolar , Femenino , Hemangioma/tratamiento farmacológico , Hemangioma Capilar/tratamiento farmacológico , Humanos , Lactante , Masculino , Propranolol/efectos adversos , Estudios Prospectivos , Neoplasias Cutáneas/tratamiento farmacológico , Resultado del Tratamiento
11.
Pediatr Emerg Care ; 38(1): e27-e28, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34986584

RESUMEN

OBJECTIVES: Children with hemophilia have the usual childhood risk of falls and head trauma. Head computed tomographies (HCTs) are fast, detailed, and readily available, but increased radiation exposure in the pediatric population is now recognized as causing increased brain malignancy. By examining the incidence of intracranial cerebral hemorrhage in this population, we will be able to weigh risks and benefits of HCT use more accurately. METHODS: Using a retrospective chart review, we examined past medical records of pediatric patients, aged 0 to 15 years, with hemophilia presenting to 1 academic medical center. Primary outcomes included number of head CTs ordered, total and per patient over the years studied, and the incidence of positive findings, as defined by presence of blood products as documented by radiologist final read/interpretation. RESULTS: The mean number of head CTs per child was 2.5 (range, 1-10). None of the HCT scans were read as intracranial cerebral hemorrhage, and none of the patients had findings that lead to neurosurgical intervention. In a sensitivity analysis, applying Pediatric Emergency Care Applied Research Network head injury criteria, 11 HCT scans would be ordered for a reduction of 80 HCTs, or a decrease of 2 HCT scans per child. No incidence of intracranial cerebral hemorrhage would have been missed. CONCLUSIONS: Our findings suggest that in the child with hemophilia and a history of minor head trauma, exposure to the radiation of a HCT based on the diagnosis of hemophilia alone may not be necessary but that imaging decisions need to be made in conjunction with clinical examination findings and neurologic status.


Asunto(s)
Traumatismos Craneocerebrales , Hemofilia A , Exposición a la Radiación , Niño , Traumatismos Craneocerebrales/complicaciones , Traumatismos Craneocerebrales/diagnóstico por imagen , Traumatismos Craneocerebrales/epidemiología , Hemofilia A/complicaciones , Hemofilia A/diagnóstico por imagen , Hemofilia A/epidemiología , Humanos , Estudios Retrospectivos , Tomografía Computarizada por Rayos X
12.
Psychooncology ; 30(8): 1383-1392, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33843104

RESUMEN

OBJECTIVE: For adolescents and young adults (AYAs), cancer-related fertility concerns (FC) are salient, disruptive, and complex. Clinical communication about FC and fertility preservation options are suboptimal, increasing patient distress. The purpose of this study is to construct a conceptual model of FC among AYAs with cancer to inform future measurement development. METHODS: Concept elicitation interviews were conducted with a purposive sample of stakeholders: 36 AYAs (10 adolescents, 12 emerging adults, and 14 young adults), 36 AYA oncology health care providers, and 12 content experts in cancer-related infertility. The constant comparative method was used to identify themes and properties that illustrate AYAs' conceptualization and/or experience of FC. RESULTS: Thirteen themes characterized FC among AYAs with cancer, varying by stakeholder group and domain affiliations. Themes were grouped by four domains (e.g., affective, information, coping, and logistical), which organized the conceptual model. Affective experiences were further determined to be an important component within the other three domains. AYAs' fertility and fertility preservation experiences were shaped by communication factors and timing factors including placement along the lifespan/cancer continuum. CONCLUSIONS: AYA FC are characterized by uncertainty and confusion that may contribute to future decisional regret or magnify feelings of loss. Results add to previous research by examining individual, relational, and health care factors that fluctuate to inform fertility preservation perceptions and decision-making across the AYA age spectrum. Findings will be used to develop and test new self-report measures of FC among AYAs with cancer and survivors using classic and modern measurement theory approaches.


Asunto(s)
Preservación de la Fertilidad , Infertilidad , Neoplasias , Adolescente , Comunicación , Humanos , Sobrevivientes , Adulto Joven
13.
Microbiology (Reading) ; 166(8): 683-694, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32558638

RESUMEN

The actinomycetes are Gram-positive bacteria belonging to the order Actinomycetales within the phylum Actinobacteria. They include members with significant economic and medical importance, for example filamentous actinomycetes such as Streptomyces species, which have a propensity to produce a plethora of bioactive secondary metabolites and form symbioses with higher organisms, such as plants and insects. Studying these bacteria is challenging, but also fascinating and very rewarding. As a Microbiology Society initiative, members of the actinomycete research community have been developing a Wikipedia-style resource, called ActinoBase, the purpose of which is to aid in the study of these filamentous bacteria. This review will highlight 10 publications from 2019 that have been of special interest to the ActinoBase community, covering 4 major components of actinomycete research: (i) development and regulation; (ii) specialized metabolites; (iii) ecology and host interactions; and (iv) technology and methodology.


Asunto(s)
Actinobacteria/fisiología , Bases de Datos Factuales , Actinobacteria/genética , Actinobacteria/crecimiento & desarrollo , Actinobacteria/metabolismo , Animales , Técnicas Bacteriológicas , Productos Biológicos/metabolismo , Investigación Biomédica/instrumentación , Investigación Biomédica/organización & administración , Microbiología Ambiental , Regulación Bacteriana de la Expresión Génica , Streptomyces/genética , Streptomyces/crecimiento & desarrollo , Streptomyces/metabolismo , Streptomyces/fisiología , Simbiosis
14.
Allergy ; 75(11): 2909-2919, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32436591

RESUMEN

BACKGROUND: Tropomyosins are highly conserved proteins, an attribute that forms the molecular basis for their IgE antibody cross-reactivity. Despite sequence similarities, their allergenicity varies greatly between ingested and inhaled invertebrate sources. In this study, we investigated the relationship between the structural stability of different tropomyosins, their endolysosomal degradation patterns, and T-cell reactivity. METHODS: We investigated the differences between four tropomyosins-the major shrimp allergen Pen m 1 and the minor allergens Der p 10 (dust mite), Bla g 7 (cockroach), and Ani s 3 (fish parasite)-in terms of IgE binding, structural stability, endolysosomal degradation and subsequent peptide generation, and T-cell cross-reactivity in a BALB/c murine model. RESULTS: Tropomyosins displayed different melting temperatures, which did not correlate with amino acid sequence similarities. Endolysosomal degradation experiments demonstrated differential proteolytic digestion, as a function of thermal stability, generating different peptide repertoires. Pen m 1 (Tm 42°C) and Der p 10 (Tm 44°C) elicited similar patterns of endolysosomal degradation, but not Bla g 7 (Tm 63°C) or Ani s 3 (Tm 33°C). Pen m 1-specific T-cell clones, with specificity for regions highly conserved in all four tropomyosins, proliferated weakly to Der p 10, but did not proliferate to Bla g 7 and Ani s 3, indicating lack of T-cell epitope cross-reactivity. CONCLUSIONS: Tropomyosin T-cell cross-reactivity, unlike IgE cross-reactivity, is dependent on structural stability rather than amino acid sequence similarity. These findings contribute to our understanding of cross-sensitization among different invertebrates and design of suitable T-cell peptide-based immunotherapies for shrimp and related allergies.


Asunto(s)
Alérgenos , Tropomiosina , Animales , Reacciones Cruzadas , Inmunoglobulina E , Ratones , Linfocitos T
15.
Pediatr Blood Cancer ; 67(2): e28065, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31736232

RESUMEN

BACKGROUND: Hypoalbuminemia is a well-recognized finding associated with cancer, but its prevalence and prognostic significance have not been well studied in children with cancer. OBJECTIVE: To determine the prevalence of hypoalbuminemia prior to starting chemotherapy in children with cancer and its association with relapse-free survival (RFS) and overall survival (OS). DESIGN/METHOD: We performed a single institution, IRB-approved, retrospective review of pediatric oncology patients diagnosed between 1998 and 2012. Five-year survival was estimated using the Kaplan-Meier method; groups were compared using Cox regression. RESULTS: We identified 659 pediatric patients with a first diagnosis of cancer and a serum albumin level prior to starting chemotherapy. Mean age was 8.6 years (SD = 5.8); 62% were male and 92% were non-Hispanic. Hypoalbuminemia prior to starting chemotherapy was present at least once in 302 (45.8%). The five-year RFS and OS of those with hypoalbuminemia and without hypoalbuminemia were not significantly different. However, patients with severe hypoalbuminemia (defined as a value 10% or more below the lower limit of normal) had inferior RFS and OS for patients with hematologic/lymphatic malignancies, and inferior RFS for patients with metstatic Ewing sarcoma. CONCLUSION: Hypoalbuminemia prior to starting chemotherapy in pediatric oncology patients is common (nearly half in this cohort). Severe hypoalbuminemia was associated with inferior 5-year RFS in some subgroups.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Hipoalbuminemia/complicaciones , Recurrencia Local de Neoplasia/mortalidad , Neoplasias/mortalidad , Adolescente , Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Lactante , Masculino , Recurrencia Local de Neoplasia/tratamiento farmacológico , Recurrencia Local de Neoplasia/etiología , Recurrencia Local de Neoplasia/patología , Neoplasias/tratamiento farmacológico , Neoplasias/etiología , Neoplasias/patología , Pronóstico , Estudios Retrospectivos , Tasa de Supervivencia
16.
Nanomedicine ; 28: 102234, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32522709

RESUMEN

Templating has been demonstrated to be an efficient method of nanocapsule preparation. However, there have been no reports of using protein-only nanocapsules as an antigen delivery system. Such a system would enable the delivery of antigen without additional polymers. This study focused on defining the structural and cellular characteristics of nanocapsules consisting of antigen (ovalbumin) alone, synthesized by the templating method using highly monodispersed solid core mesoporous shell (SC/MS) and mesoporous (MS) silica nanoparticles of 410 nm and 41 nm in diameter, respectively. The synthesized ovalbumin nanocapsules were homogeneous in structure, and cellular uptake was observed in DC2.4 murine immature dendritic cells with minimal cytotoxicity. The nanocapsules were localized intracellularly and induced antigen presentation by the cross-presentation pathway. The templating system, using SC/MS and MS silica nanoparticles, was demonstrated to be an effective nanocapsule synthesis method for a new antigen delivery system.


Asunto(s)
Células Dendríticas/metabolismo , Sistemas de Liberación de Medicamentos/métodos , Proteínas/química , Animales , Nanocápsulas/química , Dióxido de Silicio/química
17.
Microbiology (Reading) ; 165(9): 929-952, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31334697

RESUMEN

Streptomyces venezuelae is a Gram-positive, filamentous actinomycete with a complex developmental life cycle. Genomic analysis revealed that S. venezuelae encodes a large number of two-component systems (TCSs): these consist of a membrane-bound sensor kinase (SK) and a cognate response regulator (RR). These proteins act together to detect and respond to diverse extracellular signals. Some of these systems have been shown to regulate antimicrobial biosynthesis in Streptomyces species, making them very attractive to researchers. The ability of S. venezuelae to sporulate in both liquid and solid cultures has made it an increasingly popular model organism in which to study these industrially and medically important bacteria. Bioinformatic analysis identified 58 TCS operons in S. venezuelae with an additional 27 orphan SK and 18 orphan RR genes. A broader approach identified 15 of the 58 encoded TCSs to be highly conserved in 93 Streptomyces species for which high-quality and complete genome sequences are available. This review attempts to unify the current work on TCS in the streptomycetes, with an emphasis on S. venezuelae.


Asunto(s)
Antibacterianos/biosíntesis , Quinasas MAP Reguladas por Señal Extracelular/genética , Genes Reguladores , Streptomyces/genética , Evolución Molecular , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Genómica , Elementos Reguladores de la Transcripción/genética , Elementos de Respuesta/genética , Transducción de Señal/genética
18.
PLoS Pathog ; 13(10): e1006666, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28968463

RESUMEN

The RNA genomes of picornaviruses are translated into single polyproteins which are subsequently cleaved into structural and non-structural protein products. For genetic economy, proteins and processing intermediates have evolved to perform distinct functions. The picornavirus precursor protein, P3, is cleaved to produce membrane-associated 3A, primer peptide 3B, protease 3Cpro and polymerase 3Dpol. Uniquely, foot-and-mouth disease virus (FMDV) encodes three similar copies of 3B (3B1-3), thus providing a convenient natural system to explore the role(s) of 3B in the processing cascade. Using a replicon system, we confirmed by genetic deletion or functional inactivation that each copy of 3B appears to function independently to prime FMDV RNA replication. However, we also show that deletion of 3B3 prevents replication and that this could be reversed by introducing mutations at the C-terminus of 3B2 that restored the natural sequence at the 3B3-3C cleavage site. In vitro translation studies showed that precursors with 3B3 deleted were rapidly cleaved to produce 3CD but that no polymerase, 3Dpol, was detected. Complementation assays, using distinguishable replicons bearing different inactivating mutations, showed that replicons with mutations within 3Dpol could be recovered by 3Dpol derived from "helper" replicons (incorporating inactivation mutations in all three copies of 3B). However, complementation was not observed when the natural 3B-3C cleavage site was altered in the "helper" replicon, again suggesting that a processing abnormality at this position prevented the production of 3Dpol. When mutations affecting polyprotein processing were introduced into an infectious clone, viable viruses were recovered but these had acquired compensatory mutations in the 3B-3C cleavage site. These mutations were shown to restore the wild-type processing characteristics when analysed in an in vitro processing assay. Overall, this study demonstrates a dual functional role of the small primer peptide 3B3, further highlighting how picornaviruses increase genetic economy.


Asunto(s)
Virus de la Fiebre Aftosa/genética , ARN Viral/genética , Proteínas Virales/metabolismo , Replicación Viral , Animales , Replicación del ADN/genética , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Mutación/genética , ARN Viral/metabolismo , Receptores Citoplasmáticos y Nucleares/genética , Receptores Citoplasmáticos y Nucleares/metabolismo , Replicación Viral/genética
19.
Pediatr Blood Cancer ; 66(4): e27584, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30561134

RESUMEN

BACKGROUND: Little is known regarding risk factors for chemotherapy-induced nausea (CIN) in pediatric patients. PROCEDURE: A secondary analysis was conducted of a previously published multicenter, prospective, randomized, single-blind, sham-controlled trial assessing the efficacy of acupressure in preventing CIN in pediatric patients receiving highly emetogenic chemotherapy. The primary outcome was nausea severity, self-reported using the Pediatric Nausea Assessment Tool. The relationships between acute and delayed nausea severity and patient- (sex, race, age, and cancer diagnosis) and treatment-related (chemotherapy, antiemetic prophylaxis, CIN, and vomiting control) factors were analyzed by a proportional odds generalized estimating equation approach. The acute phase started with administration of the first and continued for 24 hours after the last chemotherapy dose. The delayed phase started at the end of the acute phase and continued until the next chemotherapy block (maximum seven days). RESULTS: In the acute and delayed phases, 165 and 144 patients provided data for analysis, respectively. Nonwhite race was significantly associated with higher acute phase nausea severity (OR, 1.7; 95% CI, 1.1-2.6). Poor CIN control in the acute phase (OR, 16; 95% CI, 4.0-64.6), diagnosis of a cancer other than a central nervous system (CNS) tumor (OR, 2.5; 95% CI, 1.2-5.3), and cisplatin administration (OR, 3.7; 95% CI, 2.1-6.0) were significantly associated with higher delayed phase nausea severity. CONCLUSION: Acute phase CIN was associated with nonwhite race. Delayed phase CIN was associated with poor acute phase CIN control, diagnosis of non-CNS cancer, and receipt of cisplatin. These findings will inform future antiemetic trial design.


Asunto(s)
Acupresión , Antineoplásicos/efectos adversos , Cisplatino/efectos adversos , Náusea , Neoplasias , Adolescente , Antineoplásicos/administración & dosificación , Niño , Cisplatino/administración & dosificación , Femenino , Humanos , Masculino , Náusea/inducido químicamente , Náusea/epidemiología , Náusea/terapia , Neoplasias/tratamiento farmacológico , Neoplasias/epidemiología , Factores de Riesgo
20.
Cancer ; 124(6): 1188-1196, 2018 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-29266260

RESUMEN

BACKGROUND: Chemotherapy-induced nausea and vomiting remain common, distressing side effects of chemotherapy. It has been reported that acupressure prevents chemotherapy-induced nausea in adults, but it has not been well studied in children. METHODS: In this multicenter, prospective, randomized, single-blind, sham-controlled trial, the authors compared acute-phase nausea severity in patients ages 4 to 18 years who were receiving highly emetic chemotherapy using standard antiemetic agents combined with acupressure wrist bands, the most common type of acupressure, versus sham bands. Patients wore acupressure or sham bands continuously on each day of chemotherapy and for up to 7 days afterward. Chemotherapy-induced nausea severity in the delayed phase and chemotherapy-induced vomiting control in the acute and delayed phases also were compared. RESULTS: Of the 187 patients randomized, 165 contributed nausea severity assessments during the acute phase. Acupressure bands did not reduce the severity of chemotherapy-induced nausea in the acute phase (odds ratio [OR], 1.33; 95% confidence limits, 0.89-2.00, in which an OR <1.00 favored acupressure) or in the delayed phase (OR, 1.23; 95% CL, 0.75-2.01). Furthermore, acupressure bands did not improve daily vomiting control during the acute phase (OR, 1.57; 95% CL, 0.95-2.59) or the delayed phase (OR, 0.84; 95% CL, 0.45-1.58). No serious adverse events were reported. CONCLUSIONS: Acupressure bands were safe but did not improve chemotherapy-induced nausea or vomiting in pediatric patients who were receiving highly emetic chemotherapy. Cancer 2018;124:1188-96. © 2017 American Cancer Society.


Asunto(s)
Acupresión/métodos , Antieméticos/uso terapéutico , Antineoplásicos/efectos adversos , Náusea/terapia , Neoplasias/tratamiento farmacológico , Acupresión/instrumentación , Adolescente , Niño , Preescolar , Terapia Combinada , Femenino , Humanos , Masculino , Náusea/inducido químicamente , Náusea/diagnóstico , Estudios Prospectivos , Índice de Severidad de la Enfermedad , Método Simple Ciego , Resultado del Tratamiento
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