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1.
Front Oncol ; 14: 1219796, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38665953

RESUMEN

Background: Pure germinomas account for 40% of pineal tumors and are characterized by the lack of appreciable tumor markers, thus requiring a tumor biopsy for diagnosis. MicroRNAs (miRNA) have emerged as potential non-invasive biomarkers for germ cell tumors and may facilitate the non-invasive diagnosis of pure pineal germinomas. Material and methods: A retrospective chart review was performed on all patients treated at the Children's Cancer Hospital Egypt diagnosed with a pineal region tumor between June 2013 and March 2021 for whom a research blood sample was available. Plasma samples were profiled for miRNA expression, and DESeq2 was used to compare between pure germinoma and other tumor types. Differentially expressed miRNAs were identified. The area under the curve of the receive;r operating characteristic curve was constructed to evaluate diagnostic performance. Results: Samples from 39 pediatric patients were available consisting of 12 pure germinomas and 27 pineal region tumors of other pathologies, including pineal origin tumors [n = 17; pineoblastoma (n = 13) and pineal parenchymal tumors of intermediate differentiation (n = 4)] and others [n = 10; low-grade glioma (n = 6) and atypical teratoid rhabdoid tumor (n = 4)]. Using an adjusted p-value <0.05, three miRNAs showed differential expression (miR-143-3p, miR-320c, miR-320d; adjusted p = 0.0058, p = 0.0478, and p = 0.0366, respectively) and good discriminatory power between the two groups (AUC 90.7%, p < 0.001) with a sensitivity of 25% and a specificity of 100%. Conclusion: Our results suggest that a three-plasma miRNA signature has the potential to non-invasively identify pineal body pure germinomas which may allow selected patients to avoid the potential surgical complications.

2.
Front Microbiol ; 14: 1190133, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37333655

RESUMEN

The overall pattern of the SARS-CoV-2 pandemic so far has been a series of waves; surges in new cases followed by declines. The appearance of novel mutations and variants underlie the rises in infections, making surveillance of SARS-CoV-2 mutations and prediction of variant evolution of utmost importance. In this study, we sequenced 320 SARS-CoV-2 viral genomes isolated from patients from the outpatient COVID-19 clinic in the Children's Cancer Hospital Egypt 57357 (CCHE 57357) and the Egypt Center for Research and Regenerative Medicine (ECRRM). The samples were collected between March and December 2021, covering the third and fourth waves of the pandemic. The third wave was found to be dominated by Nextclade 20D in our samples, with a small number of alpha variants. The delta variant was found to dominate the fourth wave samples, with the appearance of omicron variants late in 2021. Phylogenetic analysis reveals that the omicron variants are closest genetically to early pandemic variants. Mutation analysis shows SNPs, stop codon mutation gain, and deletion/insertion mutations, with distinct patterns of mutations governed by Nextclade or WHO variant. Finally, we observed a large number of highly correlated mutations, and some negatively correlated mutations, and identified a general inclination toward mutations that lead to enhanced thermodynamic stability of the spike protein. Overall, this study contributes genetic and phylogenetic data, as well as provides insights into SARS-CoV-2 viral evolution that may eventually help in the prediction of evolving mutations for better vaccine development and drug targets.

3.
Sci Rep ; 12(1): 14511, 2022 08 25.
Artículo en Inglés | MEDLINE | ID: mdl-36008511

RESUMEN

A serious global public health emergency emerged late November 2019 in Wuhan City, China, by a new highly pathogenic virus, SARS-CoV-2. The virus evolution spread has been tracked by three developing databases: GISAID, Nextstrain and PANGO to understand its circulating variants. In this study, 110 diagnosed positive COVID-19 patient's samples, were collected from Kasr Al-Aini Hospital and the Children Cancer Hospital Egypt 57357 between May 2020 and January 2021, with clinical severity ranging from mild to severe. The viral genomes were sequenced by next generation sequencing, and phylogenetic analysis was performed to understand viral transmission dynamics. According to Nextstrain clades, most of our sequenced samples belonged to clades 20A and 20D, which in addition to clade 20B were present from the beginning of sample collection in May 2020. Clades 19A and 19B, on the other hand, appeared in the mid and late 2020 respectively, followed by the disappearance of clade 20B at the end of 2020. We identified a relatively high prevalence of the D614G spike protein variant and novel patterns of mutations associated together and with different clades. We also identified four mutations, spike H49Y, ORF3a H78Y, ORF8 E64stop and nucleocapsid E378V, associated with higher disease severity. Altogether, our study contributes genetic, phylogenetic, and clinical correlation data about the spread of the SARS-CoV-2 pandemic in Egypt.


Asunto(s)
COVID-19 , SARS-CoV-2 , COVID-19/epidemiología , COVID-19/genética , Niño , Egipto/epidemiología , Genoma Viral , Humanos , Mutación , Pandemias , Filogenia , SARS-CoV-2/genética
4.
mSphere ; 6(6): e0072521, 2021 12 22.
Artículo en Inglés | MEDLINE | ID: mdl-34787450

RESUMEN

Infection by multidrug-resistant (MDR) Acinetobacter baumannii is one of the major causes of hospital-acquired infections worldwide. The ability of A. baumannii to survive in adverse conditions as well as its extensive antimicrobial resistance make it one of the most difficult to treat pathogens associated with high mortality rates. The aim of this study was to investigate MDR A. baumannii that has spread among pediatric cancer patients in the Children's Cancer Hospital Egypt 57357. Whole-genome sequencing was used to characterize 31 MDR A. baumannii clinical isolates. Phenotypically, the isolates were MDR, with four isolates showing resistance to the last-resort antibiotic colistin. Multilocus sequence typing showed the presence of eight clonal groups, two of which were previously reported to cause outbreaks in Egypt, and one novel sequence type (ST), Oxf-ST2246. Identification of the circulating plasmids showed the presence of two plasmid lineages in the isolates, strongly governed by sequence type. A large number of antimicrobial genes with a range of resistance mechanisms were detected in the isolates, including ß-lactamases and antibiotic efflux pumps. Analysis of insertion sequences (ISs) revealed the presence of ISAba1 and ISAba125 in all the samples, which amplify ß-lactamase expression, causing extensive carbapenem resistance. Mutation analysis was used to decipher underlying mutations responsible for colistin resistance and revealed novel mutations in several outer membrane proteins, in addition to previously reported mutations in pmrB. Altogether, understanding the transmissibility of A. baumannii as well as its resistance and virulence mechanisms will help develop novel treatment options for better management of hospital-acquired infections. IMPORTANCE Acinetobacter baumannii represents a major health threat, in particular among immunocompromised cancer patients. The rise in carbapenem-resistant A. baumannii, and the development of resistance to the last-resort antimicrobial agent colistin, complicates the management of A. baumannii outbreaks and increases mortality rates. Here, we investigate 31 multidrug resistant A. baumannii isolates from pediatric cancer patients in Children's Cancer Hospital Egypt (CCHE) 57357 via whole-genome sequencing. Multilocus sequence typing (MLST) showed the presence of eight clonal groups including a novel sequence type. In silico detection of antimicrobial-resistant genes and virulence factors revealed a strong correlation between certain virulence genes and mortality as well as several point mutations in outer membrane proteins contributing to colistin resistance. Detection of CRISPR/Cas sequences in the majority of the samples was strongly correlated with the presence of prophage sequences and associated with failure of bacteriophage therapy. Altogether, understanding the genetic makeup of circulating A. baumannii is essential for better management of outbreaks.


Asunto(s)
Infecciones por Acinetobacter/microbiología , Acinetobacter baumannii/genética , Acinetobacter baumannii/aislamiento & purificación , Farmacorresistencia Bacteriana Múltiple/genética , Tipificación de Secuencias Multilocus , Infecciones por Acinetobacter/epidemiología , Infecciones por Acinetobacter/transmisión , Acinetobacter baumannii/efectos de los fármacos , Acinetobacter baumannii/patogenicidad , Antibacterianos/farmacología , Proteínas Bacterianas/genética , Instituciones Oncológicas , Carbapenémicos/farmacología , Colistina/farmacología , Infección Hospitalaria , Egipto , Hospitales Pediátricos , Humanos , Pruebas de Sensibilidad Microbiana , Secuenciación Completa del Genoma , beta-Lactamasas/genética
5.
Biosci Rep ; 41(9)2021 09 30.
Artículo en Inglés | MEDLINE | ID: mdl-34472584

RESUMEN

Duchenne muscular dystrophy (DMD) is a fatal neuromuscular disorder that occurs due to inactivating mutations in DMD gene, leading to muscular dystrophy. Prediction of pathological complications of DMD and the identification of female carriers are important research points that aim to reduce disease burden. Herein, we describe a case of a late DMD patient and his immediate female family members, who all carry same DMD mutation and exhibited varied degrees of symptoms. In our study, we sequenced the whole miRNome in leukocytes and plasma of the family members and results were validated using real-time PCR. Our results highlighted the role of miR-409-3p, miR-424-5p, miR-144-3p as microRNAs that show correlation with the extent of severity of muscular weakness and can be used for detection of asymptomatic carriers. Cellular and circulating levels of miR-494-3p had shown significant increase in symptomatic carriers, which may indicate significant roles played by this miRNA in the onset of muscular weakness. Interestingly, circulating levels of miR-206 and miR-410-3p were significantly increased only in the severely symptomatic carrier. In conclusion, our study highlighted several miRNA species, which could be used in predicting the onset of muscle and/or neurological complications in DMD carriers.


Asunto(s)
Distrofina/genética , Perfilación de la Expresión Génica , Heterocigoto , MicroARNs/genética , Debilidad Muscular/genética , Distrofia Muscular de Duchenne/genética , Mutación , Transcriptoma , Adulto , Enfermedades Asintomáticas , Niño , Análisis Mutacional de ADN , Femenino , Predisposición Genética a la Enfermedad , Herencia , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Masculino , MicroARNs/sangre , Persona de Mediana Edad , Debilidad Muscular/diagnóstico , Debilidad Muscular/fisiopatología , Distrofia Muscular de Duchenne/diagnóstico , Distrofia Muscular de Duchenne/fisiopatología , Linaje , Fenotipo , Índice de Severidad de la Enfermedad , Adulto Joven
7.
Sci Rep ; 10(1): 4165, 2020 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-32139767

RESUMEN

Infection with multiple drug resistant (MDR) Escherichia coli poses a life threat to immunocompromised pediatric cancer patients. Our aim is to genotypically characterize the plasmids harbored in MDR E. coli isolates recovered from bacteremic patients of Children's Cancer Hospital in Egypt 57357 (CCHE 57357). In this study, 21 carbapenem-resistant E. coli (CRE) isolates were selected that exhibit Quinolones and Aminoglycosides resistance. Plasmid shot-gun sequencing was performed using Illumina next- generation sequencing platform. Isolates demonstrated resistant to all beta-lactams, carbapenems, aminoglycosides and quinolones. Of the 32 antimicrobial resistant genes identified that exceeded the analysis cutoff coverage, the highest represented genes were aph(6)-Id, sul2, aph(3″)-Ib, aph(3')-Ia, sul1, dfrA12, TEM-220, NDM-11. Isolates employed a wide array of resistance mechanisms including antibiotic efflux, antibiotic inactivation, antibiotic target replacements and antibiotic target alteration. Sequenced isolates displayed diverse insertion sequences, including IS26, suggesting dynamic reshuffling of the harbored plasmids. Most isolates carried plasmids originating from other bacterial species suggesting a possible horizontal gene transfer. Only two isolates showed virulence factors with iroA gene cluster which was found in only one of them. Outside the realms of nosocomial infections among patients in hospitals, our results indicate a transfer of resistant genes and plasmids across different organisms.


Asunto(s)
Antibacterianos/farmacocinética , Proteínas de Escherichia coli/metabolismo , Escherichia coli/efectos de los fármacos , Escherichia coli/genética , Instituciones Oncológicas/estadística & datos numéricos , Farmacorresistencia Bacteriana Múltiple/genética , Egipto , Proteínas de Escherichia coli/genética , Genotipo , Humanos , Pruebas de Sensibilidad Microbiana , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
8.
Genet Mol Biol ; 41(1): 27-34, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29658967

RESUMEN

Understanding pediatric brain tumor biology is essential to help on disease stratification, and to find novel markers for early diagnosis. MicroRNA (miRNA) expression has been linked to clinical outcomes and tumor biology. Here, we aimed to detect the expression of different miRNAs in different pediatric brain tumor subtypes to discover biomarkers for early detection and develop novel therapies. Expression of 82 miRNAs was detected in 120 pediatric brain tumors from fixed-formalin paraffin-embedded tissues, low-grade glioma, high-grade glioma, ependymoma, and medulloblastoma, using quantitative real-time PCR. Low-expression of miR-221, miR-9, and miR-181c/d and over-expression of miR-101, miR-222, miR-139, miR-1827, and miR-34c was found in medulloblastoma; low expression of miR-10a and over-expression of miR-10b and miR-29a in ependymoma; low expression of miR-26a and overexpression of miR-19a/b, miR-24, miR-27a, miR- 584, and miR-527 in low-grade glioma. Cox regression showed differential miRNA expression between responders and non-responders. The most specific were miR-10a and miR-29a low expression in LGG non-responders, miR-135a and miR-146b over-expression in ependymoma non-responders, and miR-135b overexpression in medulloblastoma non-responders. MicroRNAs are differentially expressed in subtypes of brain tumors suggesting that they may help diagnosis. A greater understanding of aberrant miRNA in pediatric brain tumors may support development of novel therapies.

9.
Genet. mol. biol ; 41(1): 27-34, Jan.-Mar. 2018. tab, graf
Artículo en Inglés | LILACS | ID: biblio-892459

RESUMEN

Abstract Understanding pediatric brain tumor biology is essential to help on disease stratification, and to find novel markers for early diagnosis. MicroRNA (miRNA) expression has been linked to clinical outcomes and tumor biology. Here, we aimed to detect the expression of different miRNAs in different pediatric brain tumor subtypes to discover biomarkers for early detection and develop novel therapies. Expression of 82 miRNAs was detected in 120 pediatric brain tumors from fixed-formalin paraffin-embedded tissues, low-grade glioma, high-grade glioma, ependymoma, and medulloblastoma, using quantitative real-time PCR. Low-expression of miR-221, miR-9, and miR-181c/d and over-expression of miR-101, miR-222, miR-139, miR-1827, and miR-34c was found in medulloblastoma; low expression of miR-10a and over-expression of miR-10b and miR-29a in ependymoma; low expression of miR-26a and overexpression of miR-19a/b, miR-24, miR-27a, miR- 584, and miR-527 in low-grade glioma. Cox regression showed differential miRNA expression between responders and non-responders. The most specific were miR-10a and miR-29a low expression in LGG non-responders, miR-135a and miR-146b over-expression in ependymoma non-responders, and miR-135b overexpression in medulloblastoma non-responders. MicroRNAs are differentially expressed in subtypes of brain tumors suggesting that they may help diagnosis. A greater understanding of aberrant miRNA in pediatric brain tumors may support development of novel therapies.

10.
Biopreserv Biobank ; 14(1): 9-16, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26691960

RESUMEN

BACKGROUND: Conducting high throughput -omics research requires high quality, data-rich biospecimens to unravel factors underlying childhood cancers; this is an extra burden in a limited resources country. For this purpose, Children's Cancer Hospital (CCHE), the largest pediatric cancer hospital worldwide, established a cutting-edge Biorepository and Biospecimen Research Facility (CCHE-BBR). OBJECTIVE: To present a step-by-step guide to establishing a hospital-based biorepository with limited resources, and working in collaboration with different hospital facilities to supply the research community with high quality data-rich biospecimens fit for a wide range of research purposes. This approach will foster research in the era of personalized precision medicine. METHODS: CCHE-IRB approved the collection and storage of biospecimens from patients and parents for future research. We focused on staff training, recruiting qualified scientists, and establishing the infrastructure. The CCHE Biorepository developed strict standardized procedures for sample acquisition, processing, annotation, storage, and distribution based on ISBER Best Practices and CAP-accreditation guidelines. We collect samples at different clinical time points (e.g., at remission and/or relapse) as well as parents' samples for genetic studies. Using CaTissue®, an electronic storage management system, allowed sample annotation and full integration with clinical data and the cancer registry. RESULTS: In 2 years, we succeeded in establishing a well-designed biorepository within our regulations, bylaws, and SOPs, and with a minimal budget. We store high quality blood derivatives, CSF, and malignant/normal tissue samples. CONCLUSION: Building a high quality biorepository with minimal-resources to encourage research is possible. Having the suitable infrastructure with a significant number of clinically annotated samples can play a major role in international research projects, sharing samples and/or data with other groups.


Asunto(s)
Bancos de Tejidos , Investigación Biomédica , Medicina de Precisión/métodos , Manejo de Especímenes/métodos
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