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The study of circulating peptides in the blood offers significant opportunities for diagnosing, stratifying, and managing various diseases. With recent technological advances and the ongoing need to understand complex diseases such as acute leukemias (AL), peptidomic analysis of peripheral blood, especially serum and plasma, has become increasingly important for studying human biology and pathophysiology. Here, we provide insights and perspectives on technological developments and potential clinical applications using widely used peptidomic analysis methods. We discuss examples where peptidomics using serum or plasma has contributed to the understanding of AL. Specifically, we highlight the scarcity of peptidomic studies applied to AL and emphasize the importance of exploring this area, as the few published studies present promising results that can significantly contribute to precision medicine.

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The anticancer potential of some antimicrobial peptides has been reported. Hs02 is a recently characterized Intragenic Antimicrobial Peptide (IAP), which was able to exhibit potent antimicrobial and anti-inflammatory action. In this study, we evaluate for the first time the antineoplastic potential of the Hs02 IAP using cell lines representing the main types of leukemia as cancer models. Interestingly, this peptide decreased the viability of several leukemic cell lines, without compromising the viability of PBMCs in the same concentration. In the HL-60 line, treatment with Hs02 controlled cell division, leading to cell arrest in the G1 phase of the cell cycle. More importantly, HL-60 cells treated with Hs02 undergo cell death, with the formation of pores in the plasma membrane and the release of LDH. Accordingly, Hs02 treatment stimulated the expression of components involved in pyroptosis, such as NLRP1, CASP-1, GSDME, and IL-1ß. Taken together, our data characterize the antineoplastic potential of Hs02 and open an opportunity for both evaluating the peptide's antineoplastic potential in other cancer models and using this molecule as a template for new peptides with therapeutic potential against cancer.

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The cell signaling pathways involved in the antiproliferative activities of T. rosea inner bark remain unexplored. This study evaluated the apoptotic effects of two iridoids from the inner bark of T. rosea and apicidin on THP-1 cells. The cytotoxic effects of the extract and the pure compounds on THP-1 and Jurkat cells were also evaluated using the MTT assay. The apoptotic effect was determined by measuring the mitochondrial membrane potential. The expression of mRNA and MAPK kinase, Bax, and Bcl-2 proteins was detected by Western blotting and RT-qPCR, respectively. The extract and the compounds evaluated increased the percentage of apoptotic cells. Depolarization of the mitochondrial membrane was observed, and the number of cells in the G0/G1 phase increased. Catalposide and specioside significantly increased p38 protein expression, mostly in cells pretreated with apicidin. The p38 MAPK signaling pathway is at least one of the pathways by which the n-butanol extract obtained from Tabebuia rosea, catalposide, and specioside exerts its apoptotic effect on THP-1 cells, and this effect generates a response in the G0/G1 phase and subsequent cell death. In addition, there was depolarization of the mitochondrial membrane, an effect that was related to the participation of the proapoptotic protein Bax.

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BACKGROUND: Tumour dormancy, a resistance mechanism employed by cancer cells, is a significant challenge in cancer treatment, contributing to minimal residual disease (MRD) and potential relapse. Despite its clinical importance, the mechanisms underlying tumour dormancy and MRD remain unclear. In this study, we employed two syngeneic murine models of myeloid leukemia and melanoma to investigate the genetic, epigenetic, transcriptomic and protein signatures associated with tumour dormancy. We used a multiomics approach to elucidate the molecular mechanisms driving MRD and identify potential therapeutic targets. RESULTS: We conducted an in-depth omics analysis encompassing whole-exome sequencing (WES), copy number variation (CNV) analysis, chromatin immunoprecipitation followed by sequencing (ChIP-seq), transcriptome and proteome investigations. WES analysis revealed a modest overlap of gene mutations between melanoma and leukemia dormancy models, with a significant number of mutated genes found exclusively in dormant cells. These exclusive genetic signatures suggest selective pressure during MRD, potentially conferring resistance to the microenvironment or therapies. CNV, histone marks and transcriptomic gene expression signatures combined with Gene Ontology (GO) enrichment analysis highlighted the potential functional roles of the mutated genes, providing insights into the pathways associated with MRD. In addition, we compared "murine MRD genes" profiles to the corresponding human disease through public datasets and highlighted common features according to disease progression. Proteomic analysis combined with multi-omics genetic investigations, revealed a dysregulated proteins signature in dormant cells with minimal genetic mechanism involvement. Pathway enrichment analysis revealed the metabolic, differentiation and cytoskeletal remodeling processes involved in MRD. Finally, we identified 11 common proteins differentially expressed in dormant cells from both pathologies. CONCLUSIONS: Our study underscores the complexity of tumour dormancy, implicating both genetic and nongenetic factors. By comparing genomic, transcriptomic, proteomic, and epigenomic datasets, our study provides a comprehensive understanding of the molecular landscape of minimal residual disease. These results provide a robust foundation for forthcoming investigations and offer potential avenues for the advancement of targeted MRD therapies in leukemia and melanoma patients, emphasizing the importance of considering both genetic and nongenetic factors in treatment strategies.

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The present study analyses the clinical characteristics of patients diagnosed with cutaneous fusarium through a systematic review of cases reported in literature. A total of 39 cases were included, of which 53% were men, 30% were women, and in 17% the sex was not specified. The age ranged from 5 to 85 years. Most cases were reported in Brazil, followed by Japan and United States of America. The most common agent was Fusarium solani, in 37.5% of the patients. Most of the affected individuals had acute myeloid leukaemia and some of the predisposing factors, which included induction chemotherapy, febrile neutropenia, and bone marrow transplantation. The clinical topography of the lesions was located in 27.5% and disseminated in 72.5%, with the most observed clinical feature outstanding the presence of papules and nodules with central necrosis in 47% of the cases. Longer survival was demonstrated in those treated with more than three antifungals. It is concluded that cutaneous fusarium is a complex and challenging clinical entity, infection in patients with leukaemias underscores the need for thorough care to decrease morbidity and mortality.

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Leukemia is associated with exposure to radiation, benzene derivatives, and pesticides. Previous research has documented an increase in work-related leukemia in the Latin American Andean region. To date, there are only few studies in Ecuador on the impact of oil exploitation on adjacent indigenous communities. Our study aims to show the impact of leukemia on the working-age population. For the calculation of morbidity and mortality rates, we used hospital discharge and death records from the National Institute of Statistics of Ecuador. These data were collected and adjusted to the corresponding province's population for further analysis. Large differences were observed between provinces in adjusted rates of leukemia mortality and morbidity in the working-age population. The variations in altitude among different areas in Ecuador give the provinces a distinct geographic identity. Likewise, the provinces with the highest morbidity and mortality rankings, such as Azuay, Loja, Imbabura, and Tungurahua, have an average altitude above 2000 meters. As a result, there are variations in the average temperature, exposure to solar and cosmic radiation, and mining and farming methods. The observed differences warrant the future collection of geolocation data for affected individuals. This could help to better understand how leukemia cases have demogrpahic hotspots in the country, identify possible risk factors associated with the disease in each region, and design more effective prevention and control strategies.

La leucemia es una enfermedad a consecuencia, además de factores genéticos, de la exposición a radiaciones, derivados del benceno y pesticidas. Investigaciones anteriores han documentado un aumento de la leucemia ocupacional en la región andina de América Latina. Hasta la fecha, existen sólo unos pocos estudios en Ecuador sobre el impacto de la explotación petrolera en las comunidades indígenas. Nuestro objetivo es mostrar el impacto de la leucemia en la población en edad de trabajar. Para el cálculo de las tasas de morbimortalidad se utilizaron los registros de altas hospitalarias y defunciones del Instituto Nacional de Estadística del Ecuador. Estos datos fueron recopilados y estimadas las tasas ajustadas. Se observaron grandes diferencias entre provincias en las tasas ajustadas de mortalidad y morbilidad por leucemia en la población en edad de trabajar. Asimismo, las provincias con mayor ranking de morbilidad y mortalidad, como Azuay, Loja, Imbabura y Tungurahua, coinciden en tener una altitud promedio superior a los 2000 metros. Hay provincias de baja altitud en la costa y provincias por encima de los 2000 metros en la sierra, lo que le da a las provincias del Ecuador una identidad geográfica distintiva. Como resultado, existen variaciones en la temperatura promedio, la exposición a la radiación solar y cósmica, y actividades de minería y agricultura. Las diferencias observadas, recomiendan la recopilación futura de datos de geolocalización de las personas afectadas. Esto podría ayudarnos a comprender mejor cómo se distribuyen los casos de leucemia, identificar posibles factores de riesgo asociados a la enfermedad en cada región y diseñar estrategias de prevención y control más efectivas.

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l-asparaginases play a crucial role in the treatment of acute lymphoblastic leukemia (ALL), a type of cancer that mostly affects children and teenagers. However, it is common for these molecules to cause adverse reactions during treatment. These downsides ignite the search for novel asparaginases to mitigate these problems. Thus, this work aimed to produce and characterize a recombinant asparaginase from Phaseolus vulgaris (Asp-P). In this study, Asp-P was expressed in Escherichia coli with high yields and optimum activity at 40 °C, pH 9.0. The enzyme Km and Vmax values were 7.05 mM and 1027 U/mg, respectively. Asp-P is specific for l-asparagine, showing no activity against l-glutamine and other amino acids. The enzyme showed a higher cytotoxic effect against Raji than K562 cell lines, but only at high concentrations. In silico analysis indicated that Asp-P has lower immunogenicity than a commercial enzyme. Asp-P induced biofilm formation by Candida sp. due to sublethal dose, showing an underexplored potential of asparaginases. The absence of glutaminase activity, lower immunogenicity and optimal activity similar to physiological temperature conditions are characteristics that indicate Asp-P as a potential new commercial enzyme in the treatment of ALL and its underexplored application in the treatment of other diseases.

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El sangrado uterino anormal tiene una etiología variable, que va desde causas estructurales hasta causas funcionales, que se describen clásicamente en el acrónimo PALM-COEIN. No obstante, hay una pobre sensibilización de este síntoma como un marcador de enfermedades graves. En esta revisión se describe la relación de la hemorragia uterina anormal como síntoma clave o de presentación de malignidad hematológica, así como la posible relación con la hemofilia adquirida secundaria a neoplasia hematológica como causal del evento hemostático. Se realizó búsqueda en la literatura, con la mayoría de los artículos obtenidos de Medline, 24 de los cuales cumplieron con los objetivos para resolver la pregunta de investigación. Se encontraron diferentes malignidades hematológicas asociadas a sangrado uterino anormal, de las cuales la hemofilia adquirida y la trombocitopenia como potenciales causales de esta; la mayor correlación fue con leucemia, seguido de linfomas, y en menor cuantía la asociación con mieloma múltiple.

Abnormal uterine bleeding has a variable etiology, ranging from structural to functional causes, classically described by the acronym PALM-COEIN. However, there is poor awareness of this symptom as a marker of serious disease; in this review, we describe the relationship of abnormal uterine bleeding as a key symptom or debut of hematologic malignancy, as well as its possible relationship to acquired hemophilia secondary to hematologic neoplasia as causative of the hemostatic event. A literature search was performed, with most of the articles obtained from Medline, 24 of which met the objectives to solve the research question. Different hematological malignancies associated with abnormal uterine bleeding were found, of which acquired hemophilia and thrombocytopenia were found as potential causes; the highest correlation was with leukemia, followed by lymphomas, and to a lesser extent the association with multiple myeloma.

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Magonia pubescens is a natural species from the Brazilian cerrado biome. Its fruits and seeds are used in the treatment of seborrheic dermatitis, a common inflammatory skin disease. In this work, the known compounds lapachol, stigmasterol, maniladiol and scopoletin were isolated from hexane and dichloromethane extracts of M. pubescens branches. The aqueous extract of this material was fractioned through a liquid-liquid partition and the obtained fractions were analyzed by UHPLC-MS/MS. The results obtained were compared with data from three databases, leading to the putative identification of 51 compounds from different classes, including flavonoids, saponins and triterpenes. The cytotoxicity of aqueous fractions was assayed against breast cancer (MDA-MB-231) and leukemia (THP-1 and K562) cells. The best activity was observed for fraction AE3 against MDA-MB-231 cells (IC50 30.72 µg.mL-1).

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Acute leukemias present therapeutic challenges despite advances in treatments. Microtubule inhibitors have played a pivotal role in cancer therapy, inspiring exploration into novel compounds like C2E1 from the cyclopenta[b]indole class. In the present study, we investigated C2E1's potential as a therapeutic agent for acute leukemia at molecular, cellular, and genetic levels. C2E1 demonstrated tubulin depolarization activity, significantly reducing leukemia cell viability. Its impact involved multifaceted mechanisms: inducing apoptosis, arrest of cell cycle progression, and inhibition of clonogenicity and migration in leukemia cells. At a molecular level, C2E1 triggered DNA damage, antiproliferative, and apoptosis markers and altered gene expression related to cytoskeletal regulation, disrupting essential cellular processes crucial for leukemia cell survival and proliferation. These findings highlight C2E1's promise as a potential candidate for novel anti-cancer therapies. Notably, its distinct mode of action from conventional microtubule-targeting drugs suggests the potential to bypass common resistance mechanisms encountered with existing treatments. In summary, C2E1 emerges as a compelling compound with diverse effects on leukemia cells, showcasing promising antineoplastic properties. Its ability to disrupt critical cellular functions selective to leukemia cells positions it as a candidate for future therapeutic development.

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Background and Objectives: Leukemia, characterized by abnormal leukocyte production, exhibits clonal origin from somatic mutations. Globally, it ranked 15th in cancer incidence in 2020, with higher prevalence in developing countries. In Mexico, it was the ninth most frequent cancer. Regional registries are vital for understanding its epidemiology. This study aims to analyze the prevalence and age-standardized incidence rates of leukemias in a tertiary care hospital in the Mexican Bajio region. Materials and Methods: Leukemia cases from 2008-2018 were analyzed, and 535 medical records were included in this study. The prevalence, distribution, and age-specific incidence rate of different types and subtypes of leukemia were determined according to sex and age groups. Results: Overall, 65.79% consisted of lymphocytic leukemia, 33.64% of myeloid leukemia, and 0.56% of monocytic leukemia. No significant sex-based differences were found, but age-specific patterns were observed. Leukemia distribution by age revealed significant associations. Lymphocytic leukemia dominated in the pediatric population, particularly acute lymphocytic leukemia, while myeloid leukemia shifted towards adulthood. Age-specific incidence patterns showed, first, that lymphocytic leukemia is the most common leukemia in pediatric ages, and second, there is a shift from acute lymphocytic leukemia dominance in pediatric ages to myeloid leukemia incidence in late adulthood, emphasizing nuanced epidemiological dynamics. Conclusions: Acute leukemia cases occurred with high prevalence in our study population, with a high incidence in pediatric and adulthood populations, especially for acute lymphocytic leukemia, showing a (<18 years) 153.8 age-standardized incidence rate in the pediatric group, while in the adult population, the age-standardized rate was 59.84. In the age-specific analysis, we found that the childhood group (5-9 years) were the most affected by acute lymphocytic leukemia in the pediatric population, while in the adult population, the early-adulthood group (15-29 years) were the most affected age group. In contrast, chronic myeloid leukemia affected both adults and the pediatric populations, while chronic lymphocytic leukemia and monocytic leukemia were exclusive to adults. The study underscores the need for tailored diagnostic, treatment, and preventive strategies based on age, contributing valuable insights into the leukemia epidemiology of the Bajio region.

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Periodontal disease is a highly prevalent chronic inflammatory disease that affects the tissues that support the teeth, while leukemia is a type of malignous cancer that affects the production of blood cells. Recent studies suggest that immune response and microbial disbiosis related to periodontal disease may be associated with an increased risk of developing leukemia and may affect its prognosis, as well as leukemia type and treatment may also have effects on the periodontium, demanding a interdiscipinary approach of these patients. The aim of this study was to conduct a literature review to assess the association between periodontal disease and leukemia in adult patients. An electronic database serch using the descriptors was performed. Clinical studies with periodontal examination in adult individuals with leukemia were selected. After literature search, 9 studies were reviewed. Gingival bleeding and periodontal pockets were frequent findings. Periodontitis prevalence varied among studies, ranging from 29% to 82,4% in patients diagnosed with leukemia. The relationship between periodontal disease and leukemia is complex and multifaceted and there are few studies available in adults, with heterogeneous exam protocols. Still, the high prevalence of gingivitis and periodontitis found in the studies suggest that periodontal diagnosis and treatment could be a helpful tool to prevent further complications in leukemia treatment.

A doença periodontal é uma doença inflamatória crônica altamente prevalente e que afeta os tecidos que sustentam os dentes, enquanto a leucemia é um tipo de câncer maligno que afeta a produção de células sanguíneas. Estudos recentes sugerem que a resposta imune e a disbiose microbiana relacionada a doença periodontal podem estar associadas a um risco aumentado de desenvolver leucemia e pode afetar o prognóstico da doença, assim como o tipo de leucemia e o tratamento também podem ter efeitos no periodonto, exigindo uma abordagem interdisciplinar desses pacientes. O objetivo deste estudo foi realizar uma revisão de literatura para avaliar a associação entre doença periodontal e leucemia em pacientes adultos. Foi realizada uma busca eletrônica em bancos de dados utilizando os descritores. Foram selecionados estudos clínicos com exame periodontal em indivíduos adultos com leucemia. Após busca na literatura, 9 estudos foram revisados. Sangramento gengival e bolsas periodontais foram achados frequentes. A prevalência da periodontite variou entre os estudos, sendo de 29% a 82,4% em pacientes diagnosticados com leucemia. A relação entre doença periodontal e leucemia é complexa e multifacetada e existem poucos estudos disponíveis em adultos, com protocolos de exames heterogêneos. Ainda assim, a alta prevalência de gengivite e periodontite encontrada nos estudos sugere que o diagnóstico e o tratamento periodontal podem ser uma ferramenta útil para prevenir maiores complicações no tratamento da leucemia.

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Klebsiella pneumoniae is an opportunistic pathogen that can colonize the gastrointestinal tract (GIT) of humans. The mechanisms underlying the successful translocation of this pathogen to cause extra-intestinal infections remain unknown, although virulence and antimicrobial resistance traits likely play significant roles in the establishment of infections. We investigated K. pneumoniae strains isolated from GIT colonization (strains Kp_FZcol-1, Kp_FZcol-2 and Kp_FZcro-1) and from a fatal bloodstream infection (strain Kp_HM-1) in a leukemia patient. All strains belonged to ST307, carried a transferable IncF plasmid containing the blaCTX-M-15 gene (pKPN3-307 TypeA-like plasmid) and showed a multidrug-resistance phenotype. Phylogenetic analysis demonstrated that Kp_HM-1 was more closely related to Kp_FZcro-1 than to the other colonizing strains. The Kp_FZcol-2 genome showed 81 % coverage with the Kp_HM-1 246,730 bp plasmid (pKp_HM-1), lacking most of its putative virulence genes. Searching public genomes with similar coverage, we observed the occurrence of this deletion in K. pneumoniae ST307 strains recovered from human colonization and infection in different countries. Our findings suggest that strains lacking the putative virulence genes found in the pKPN3-307 TypeA plasmid are still able to colonize and infect humans, highlighting the need to further investigate the role of these genes for the adaptation of K. pneumoniae ST307 in distinct human body sites.

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BACKGROUND: Childhood leukemia (CL) is the most prevalent form of pediatric cancer on a global scale. However, there is a limited understanding of the dynamics of CL incidence in South America, with a specific knowledge gap in Colombia. This study aimed to identify trends in CL incidence and to analyze the effects of age, period, and birth cohort on the risk of leukemia incidence in this population. METHODS: Information on all newly diagnosed leukemia cases (in general and by subtype) among residents aged 0-18 years and living in the serving areas of population-based cancer registries of Cali (2008-2017), Bucaramanga (2000-2017), Manizales (2003-2017), and Pasto (1998-2018). Estimated annual percent changes (EAPC) in incidence over time and potential changes in the slope of these EAPCs were calculated using joinpoint regression models. The effects of age, period, and cohort in CL incidence trends were evaluated using age-period-cohort models addressing the identifiability issue through the application of double differences. RESULTS: A total of 966 childhood leukemia cases were identified. The average standardized incidence rate (ASIR) of leukemia was calculated and expressed per 100,000 person-years - observing ASIR of 4.46 in Cali, 7.27 in Bucaramanga, 3.89 in Manizales and 4.06 in Pasto. Concerning CL trends there were no statistically significant changes in EAPC throughout the different periods, however, when analyzed by leukemia subtype, statistically significant changes were observed in the EAPC for both ALL and AML. Analysis of age-period-cohort models revealed that age-related factors significantly underpin the incidence trends of childhood leukemia in these four Colombian cities. CONCLUSIONS: This study offers valuable insights into the incidence trends of childhood leukemia in four major Colombian cities. The analysis revealed stable overall CL incidence rates across varying periods, predominantly influenced by age-related factors and the absence of cohort and period effects. This information is useful for surveillance and planning purposes for CL diagnosis and treatment in Colombia.

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Abstract Objective The purpose of this study was to evaluate the clinical-epidemiological profile, associated risk factors and clinical outcomes of patients with acute myeloid leukemia (AML), identifying the main causes of morbidity and mortality and overall survival rate of patients at five years of follow-up. Method This was a retrospective cohort study evaluating the prognosis and clinical outcomes of 222 patients diagnosed with AML at three large hematology centers in Ceará (northeastern Brazil) over a period of five years. Results The mean age at diagnosis was 44.1 ± 16 years, with a female prevalence of 1.3:1. No additional relevant risk factors associated with the development of AML were found, except for the well-established cytogenetic assessment. The overall 5-year survival rate was 39.4% (95%CI: 35.47 - 42.17). The main causes of death were disease progression (37.72%; n = 84) and sepsis (31.58%; n = 70). Conclusion The clinical outcomes in our sample of AML patients were similar to those of other reported groups. Disease progression and infection were the main causes of death. Access to diagnostic flow cytometry and karyotyping was greater in our sample than in the national average. As expected, overall survival differed significantly according to the risk, as determined by cytogenetic testing.

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Introducción: La tasa de mortalidad de la candidemia es variable, pero puede estar influenciada por la patología de base, en especial aquella que condiciona la presencia de neutropenia. En niños con patología oncohematológica, son pocos los trabajos que han abordado la mortalidad relacionada a candidemias y sus factores asociados. Las preguntas que promueven esta revisión sistemática, son: ¿Cuáles son las características epidemiológicas, clínicas y de evolución de los pacientes pediátricos oncohematológicos con candidemia? ¿Cuál es la mortalidad relacionada con esta entidad? Materiales y métodos: Revisión sistemática de la literatura. Se utilizaron los siguientes términos de búsqueda: candidemia por Candida spp. y los siguientes filtros humanos, niños y adolescentes y patología oncohematológica. Se revisaron los artículos publicados en inglés, español o francés hasta el 21 de septiembre de 2023. Las referencias bibliográficas de los artículos incluidos se revisaron manualmente para identificar estudios relevantes adicionales. Resultados: Se encontraron 66 artículos. Del análisis cualitativo realizado en sus textos completos, quedaron finalmente 4 estudios que se consideró que cumplían con los criterios de inclusión. Todos los artículos seleccionados sumaron 191 pacientes con diversas patologías oncohematológicas. La presencia de accesos vasculares fue frecuente en esta serie y la no extracción del catéter venoso central fue el factor más prevalente entre los que fallecieron. El agente infectante predominante fue Candida no albicans y la mortalidad osciló entre el 11,3 y el 31% con una mediana de 25%. No fue posible establecer si la especie de Candida influía en la letalidad

Introduction: The mortality rate of candidemia is variable, but may be influenced by underlying diseases, especially those causing neutropenia. In children with cancer and blood disorders, few studies have addressed mortality related to candidemia and its associated factors. The questions that motivated this systematic review were: What are the epidemiological, clinical and outcome characteristics of pediatric cancer patients with candidemia? What is the mortality related to this condition? Materials and methods: Systematic review of the literature. The following search terms were used: Candida spp., candidemia, with the following filters: human, children and adolescents, and cancer and blood disorders. Articles published in English, Spanish, or French up to September 21, 2023 were reviewed. References of included articles were manually reviewed to identify additional relevant studies. Results: 66 articles were identified. From the qualitative analysis carried out on their full texts, 4 studies that were considered to meet the inclusion criteria were finally selected. The selected articles included a total of 191 patients with various types of cancer and blood disorders. The presence of vascular access was common in this series and failure to remove the central venous catheter was the most prevalent factor among those who died. The predominant infectious agent was non-albicans Candida and mortality ranged from 11.3% to 31% with a median of 25%. It was not possible to establish whether Candida species influenced mortality.

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BACKGROUND: In hematologic cancers, including leukemia, cells depend on amino acids for rapid growth. Anti-metabolites that prevent their synthesis or promote their degradation are considered potential cancer treatment agents. Amino acid deprivation triggers proliferation inhibition, autophagy, and programmed cell death. L-lysine, an essential amino acid, is required for tumor growth and has been investigated for its potential as a target for cancer treatment. L-lysine α-oxidase, a flavoenzyme that degrades L-lysine, has been studied for its ability to induce apoptosis and prevent cancer cell proliferation. In this study, we describe the use of L-lysine α-oxidase (LO) from the filamentous fungus Trichoderma harzianum for cancer treatment. RESULTS: The study identified and characterized a novel LO from T. harzianum and demonstrated that the recombinant protein (rLO) has potent and selective cytotoxic effects on leukemic cells by triggering the apoptotic cascade through mitochondrial dysfunction. CONCLUSIONS: The results support future translational studies using the recombinant LO as a potential drug for the treatment of leukemia.

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Reference genes are used as internal reaction controls for gene expression analysis, and for this reason, they are considered reliable and must meet several important criteria. In view of the absence of studies regarding the best reference gene for the analysis of acute leukemia patients, a panel of genes commonly used as endogenous controls was selected from the literature for stability analysis: Glyceraldehyde-3-phosphate dehydrogenase (GAPDH), Abelson murine leukemia viral oncogene human homolog 1 (ABL), Hypoxanthine phosphoribosyl-transferase 1 (HPRT1), Ribosomal protein lateral stalk subunit P0 (RPLP0), ß-actin (ACTB) and TATA box binding protein (TBP). The stability of candidate reference genes was analyzed according to three statistical methods of assessment, namely, NormFinder, GeNorm and R software (version 4.0.3). From this study's analysis, it was possible to identify that the endogenous set composed of ACTB, ABL, TBP and RPLP0 demonstrated good performances and stable expressions between the analyzed groups. In addition to that, the GAPDH and HPRT genes could not be classified as good reference genes, considering that they presented a high standard deviation and great variability between groups, indicating low stability. Given these findings, this study suggests the main endogenous gene set for use as a control/reference for the gene expression in peripheral blood and bone marrow samples from patients with acute leukemias is composed of the ACTB, ABL, TBP and RPLP0 genes. Researchers may choose two to three of these housekeeping genes to perform data normalization.