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1.
Molecules ; 28(15)2023 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-37570698

RESUMO

Nanotechnology has assumed a significant role over the last decade in the development of various technologies applied to health sciences. This becomes even more evident with its application in controlled drug delivery systems. In this context, peptoids are a promising class of compounds for application as nanocarriers in drug delivery systems. These compounds can be obtained efficiently and with highly functionalized structural diversity via the Ugi 4-component reaction (U-4CR). Herein, we report the design of the process control strategy for the future development of lipid-peptoid-based customized drug delivery system assemblies. Over 20 lipid-peptoid nanocomposites were synthesized via the U-4CR in good to excellent yields. These products were successfully submitted to the nanoparticle formation by the emulsification-evaporation process from lipophilic solution and analyzed via Dynamic Light Scattering (DLS). Several molecules generated nanoparticles with a size ≤200 nm, making them good candidates for drug delivery systems, such as in cancer treatment.


Assuntos
Nanocompostos , Nanopartículas , Peptoides , Peptoides/química , Sistemas de Liberação de Medicamentos , Lipídeos
2.
Mol Cytogenet ; 11: 2, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29344089

RESUMO

BACKGROUND: The majority of the cases of bone marrow failure syndromes/aplastic anaemias (BMFS/AA) are non-hereditary and considered idiopathic (80-85%). The peripheral blood picture is variable, with anaemia, neutropenia and/or thrombocytopenia, and the patients with idiopathic BMFS/AA may have a risk of transformation into a myelodysplastic syndrome (MDS) and/or an acute myeloid leukaemia (AML), as ascertained for all inherited BMFS. We already reported four patients with different forms of BMFS/AA with chromosome anomalies as primary etiologic event: the chromosome changes exerted an effect on specific genes, namely RUNX1, MPL, and FLI1, leading to the disease. RESULTS: We report two further patients with non-hereditary BM failure, with diagnosis of severe aplastic anaemia and pancytopenia caused by two different constitutional structural anomalies involving chromosome 8, and possibly leading to the disorder due to effects on the RUNX1T1 gene, which was hypo-expressed and hyper-expressed, respectively, in the two patients. The chromosome change was unbalanced in one patient, and balanced in the other one. CONCLUSIONS: We analyzed the sequence of events in the pathogenesis of the disease in the two patients, including a number of non-haematological signs present in the one with the unbalanced anomaly. We demonstrated that in these two patients the primary event causing BMFS/AA was the constitutional chromosome anomaly. If we take into account the cohort of 219 patients with a similar diagnosis in whom we made cytogenetic studies in the years 2003-2017, we conclude that cytogenetic investigations were instrumental to reach a diagnosis in 52 of them. We postulate that a chromosome change is the primary cause of BMFS/AA in a not negligible proportion of cases, as it was ascertained in 6 of these patients.

3.
Rev. méd. Chile ; 145(2): 264-268, feb. 2017. ilus
Artigo em Espanhol | LILACS | ID: biblio-845533

RESUMO

Eyelid retraction, has received limited attention and it has passively been interpreted as the result of an overactive levator palpebrae superioris muscle secondary to midbrain injury. However, eyelid retractions can occur in other neurological diseases, not directly related with the midbrain. We report three patients who developed eyelid retraction. One patient had a bilateral eyelid retraction, related with Creutzfeldt-Jakob disease (CJD). Another patient had a unilateral right eyelid retraction associated with a thalamic-mesencephalic infarct. The third patient had a bilateral pontine infarction on magnetic resonance imaging. In the patient with CJD, eyelid retraction did not subside. Among patients with infarctions, the retraction persisted after focal symptoms had subsided, showing an evolution that was apparently independent of the basic process. The analysis of these patients allows us to conclude that the pathogenesis of eyelid retraction includes supranuclear mechanisms in both the development and maintenance of the phenomenon. Unilateral or bilateral eyelid retraction does not alter the normal function of eyelid, which ever had normal close eye blink. In these reported cases, a hyperactivity of levator palpebrae superioris muscle was clinically ruled out.


Assuntos
Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Síndrome de Creutzfeldt-Jakob/complicações , Infarto Encefálico/complicações , Doenças Palpebrais/etiologia , Doenças Musculares/complicações , Músculos Oculomotores , Imageamento por Ressonância Magnética , Síndrome de Creutzfeldt-Jakob/diagnóstico por imagem , Infarto Encefálico/diagnóstico por imagem , Doenças Palpebrais/diagnóstico
4.
Nanotoxicology ; 10(1): 84-93, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-25938282

RESUMO

The use of cadmium sulphide quantum dots (CdS QDs) is increasing, particularly in the electronics industry. Their size (1-10 nm in diameter) is, however, such that they can be taken up by living cells. Here, a bakers' yeast (Saccharomyces cerevisiae) deletion mutant collection has been exploited to provide a high-throughput means of revealing the genetic basis for tolerance/susceptibility to CdS QD exposure. The deletion of 112 genes, some associated with the abiotic stress response, some with various metabolic processes, some with mitochondrial organization, some with transport and some with DNA repair, reduced the level of tolerance to CdS QDs. A gene ontology analysis highlighted the role of oxidative stress in determining the cellular response. The transformation of sensitive mutants with centromeric plasmids harbouring DNA from a wild type strain restored the wild type growth phenotype when the complemented genes encoded either HSC82, DSK2 or ALD3. The use of these simple eukaryote knock-out mutants for functional toxicogenomic analysis will inform studies focusing on higher organisms.


Assuntos
Compostos de Cádmio/toxicidade , Pontos Quânticos , Saccharomyces cerevisiae/efeitos dos fármacos , Sulfetos/toxicidade , Reparo do DNA , Genoma Fúngico , Mutação , Nistatina/farmacologia , Estresse Oxidativo , Saccharomyces cerevisiae/genética
5.
Oncogene ; 30(27): 3096-103, 2011 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-21478910

RESUMO

The p53 transcription factor has a critical role in cell stress response and in tumor suppression. Wild-type p53 protein is a growth modulator and its inactivation is a critical event in malignant transformation. It has been recently demonstrated that wild-type p53 has developmental and differentiation functions. Indeed an over-expression of p53 in tumor cells induces asymmetrical division avoiding self-renewal of cancer stem cells (CSCs) and instead promoting their differentiation. In this study, 28 human breast carcinomas have been analyzed for expression of wild-type p53 and of a pool of non-clustered homeobox genes. We demonstrated that orthodenticle homolog 1 gene (OTX1) is transcribed in breast cancer. We established that the p53 protein directly induces OTX1 expression by acting on its promoter. OTX1 has been described as a critical molecule for axon refinement in the developing cerebral cortex of mice, and its activity in breast cancer suggests a synergistic function with p53 in CSC differentiation. Wild-type p53 may regulate cellular differentiation by an alternative pathway controlling OTX1 signaling only in breast cancer cells and not in physiological conditions.


Assuntos
Neoplasias da Mama/metabolismo , Regulação Neoplásica da Expressão Gênica/fisiologia , Fatores de Transcrição Otx/genética , Proteína Supressora de Tumor p53/fisiologia , Neoplasias da Mama/genética , Feminino , Humanos
6.
Leukemia ; 23(4): 708-11, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19148133

RESUMO

Shwachman-Diamond syndrome (SDS) is an autosomal recessive disorder, characterized by exocrine pancreatic insufficiency, skeletal abnormalities and bone marrow (BM) dysfunction with an increased risk to develop myelodysplastic syndrome and/or acute myeloid leukaemia (MDS/AML). SDS is caused, in nearly 90% of cases, by two common mutations (that is, c.183_184TA>CT and c.258+2T>C) in exon 2 of the SBDS gene, localized on chromosome 7. Clonal chromosome anomalies are often found in the BM of SDS patients; the most frequent is an isochromosome for long arms of chromosome 7, i(7)(q10). We studied eight patients with SDS carrying the i(7)(q10) who were compound heterozygotes for SBDS mutations. By assessing the parental origin of the i(7)(q10) using microsatellite analysis, we inferred from the results which mutation was present in double dose in the isochromosome. We demonstrate that in all cases the i(7)(q10) carries a double dose of the c.258+2T>C, and we suggest that, as the c.258+2T>C mutation still allows the production of some amount of normal protein, this may contribute to the low incidence of MDS/AML in this subset of SDS patients.


Assuntos
Cromossomos Humanos Par 7 , Isocromossomos , Mutação , Síndromes Mielodisplásicas/etiologia , Proteínas/genética , Adolescente , Criança , Pré-Escolar , Heterozigoto , Humanos , Lactente , Leucemia Mieloide Aguda/etiologia , Síndrome , Adulto Jovem
8.
Leukemia ; 15(6): 971-5, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11417485

RESUMO

Trisomic cells in neoplasms may represent abnormal clones originated from a tissue-confined mosaicism, and arise therefore by a meiotic error. We report on a 16-month-old child with erythroleukaemia (AML-M6), whose marrow karyotype at onset was 48,XX,del(13)(q12q14),del(14)(q22q32),+21,+21. The parental origin of the supernumerary chromosomes 21 was investigated by comparing 10 polymorphic loci scattered along the whole chromosome on the patient's marrow and her parents' leukocytes. Three loci were informative for the presence of three alleles, two of which were of maternal origin; two further loci showed a maternal allele of higher intensity. Lymphocytes and skin fibroblasts showed a normal karyotype, and molecular analysis on leukocytes at remission, buccal smear and urinary sediment cells consistently showed only one maternal allele, whereas neonatal blood from Guthrie spot showed two maternal alleles as in the marrow. An accurate clinical re-evaluation confirmed a normal phenotype. Our results indicate that tetrasomy 21 arose from a marrow clone with trisomy 21 of meiotic origin. To the best of our knowledge, this is the first evidence that supernumerary chromosomes in neoplastic clones may in fact be present due to a meiotic error. This demonstrates that a tissue-confined constitutional mosaicism for a trisomy may indeed represent the first event in multistep carcinogenesis.


Assuntos
Cromossomos Humanos Par 21 , Leucemia Eritroblástica Aguda/genética , Meiose , Mosaicismo/genética , Trissomia , Alelos , Aneuploidia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Medula Óssea/patologia , Transplante de Medula Óssea , Pré-Escolar , Células Clonais/patologia , Terapia Combinada , Dermatoglifia , Síndrome de Down/genética , Feminino , Sangue Fetal/química , Sangue Fetal/citologia , Seguimentos , Humanos , Hibridização in Situ Fluorescente , Interfase , Cariotipagem , Leucemia Eritroblástica Aguda/tratamento farmacológico , Leucemia Eritroblástica Aguda/terapia , Repetições de Microssatélites , Modelos Genéticos , Não Disjunção Genética
10.
Cancer Genet Cytogenet ; 124(2): 147-51, 2001 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-11172908

RESUMO

Two sisters are reported, both with a myelodysplastic syndrome (MDS) associated with partial monosomy 7. A trisomy 8 was also present in one of them, who later developed an acute myeloid leukemia (AML) of the M0 FAB-type and died, whereas the other died with no evolution into AML. Besides FISH studies, microsatellite analysis was performed on both sisters to gather information on the parental origin of the chromosome 7 involved in partial monosomy and of the extra chromosome 8. The chromosomes 7 involved were of different parental origin in the two sisters, thus confirming that familial monosomy 7 is not explained by a germ-line mutation of a putative tumor-suppressor gene. Similar results were obtained in two other families out of the 12 reported in the literature. Noteworthy is the association with a mendelian disease in 3 out of 12 monosomy 7 families, which suggest that a mutator gene, capable of inducing both karyotype instability and a mendelian disorder, might act to induce chromosome 7 anomalies in the marrow. We postulate that, in fact, an inherited mutation in any of a group of mutator genes causes familial monosomy 7 also in the absence of a recognized mendelian disease, and that marrow chromosome 7 anomalies, in turn, lead to MDS/AML.


Assuntos
Cromossomos Humanos Par 7 , Monossomia , Síndromes Mielodisplásicas/genética , Síndromes Mielodisplásicas/terapia , Adulto , Anemia Refratária/genética , Transplante de Medula Óssea , Criança , Pré-Escolar , Feminino , Humanos , Mutação , Síndromes Mielodisplásicas/sangue , Linhagem
11.
Cancer Genet Cytogenet ; 124(1): 12-5, 2001 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-11165316

RESUMO

A reciprocal translocation (9;11) is often found in acute myeloid leukemia (AML), mostly of the M5a type. We report a case of a child with AML, in whom t(9;11) was observed at diagnosis as the sole structural abnormality, together with trisomies 19 and 21. The diagnosis was AML evolving from a myelodysplastic syndrome (MDS), and the blast morphology was undifferentiated. Chemotherapy failed to induce morphological remission and the patient's condition soon worsened. A subclone appeared and expanded during the course of the disease, with an additional unbalanced translocation (1;17) leading to trisomy of the long arm of chromosome 17 (17q). The data available from the literature on acquired anomalies involving 17q and our observation led us to postulate a specific link between the gain of 17q and complete chemoresistance.


Assuntos
Cromossomos Humanos Par 17/genética , Cromossomos Humanos Par 21/genética , Leucemia Mieloide/genética , Trissomia/genética , Doença Aguda , Anemia Refratária com Excesso de Blastos/genética , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Pré-Escolar , Cromossomos Humanos Par 1/genética , Cromossomos Humanos Par 9/genética , Progressão da Doença , Evolução Fatal , Marcadores Genéticos , Humanos , Hibridização in Situ Fluorescente , Cariotipagem , Leucemia Mieloide/tratamento farmacológico , Masculino , Prognóstico
12.
Cancer Genet Cytogenet ; 121(2): 167-71, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11063802

RESUMO

Shwachman syndrome (SS) is an autosomal recessive disorder in which bone marrow dysfunction is observed, with development of myelodysplastic syndromes (MDS) and acute myeloid leukemias (AML) in up to one third of the cases. Inconclusive data are available as to increased chromosome breakage in SS, while chromosome 7 anomalies, and often an isochromosome (7)(q10), are frequent in cases with MDS/AML. We report on the consistent presence of an i(7)(q10) in the bone marrow and blood lymphocytes in one of two sisters affected with SS without any clinical or cytological signs of MDS/AML. Thus, this patient was either a case of constitutional mosaicism for the i(7)(q10), or this had to be acquired in a nondysplastic and non-neoplastic marrow clone. DNA polymorphism analysis demonstrated the paternal origin of the i(7q). We postulate that the SS mutation acts as a mutator gene, and causes karyotype instability; abnormal clones would thus arise in the marrow, and chromosome 7 anomalies, i(7q) in particular, will in turn lead to MDS/AML. If this interpretation is correct, it would be also an indication to consider chromosome 7 anomalies in general, out of SS, as primary changes in MDS/AML pathogenesis.


Assuntos
Doenças da Medula Óssea/genética , Cromossomos Humanos Par 7 , Isocromossomos , Leucemia Mieloide Aguda/genética , Síndromes Mielodisplásicas/genética , Pré-Escolar , Insuficiência Pancreática Exócrina/genética , Feminino , Humanos , Masculino , Linhagem , Síndrome
13.
Cancer Genet Cytogenet ; 116(2): 124-32, 2000 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-10640144

RESUMO

Recent studies have shown that structural abnormalities of chromosome 17 resulting in gain of material are the most frequent genetic changes in neuroblastoma. We have established a new neuroblastoma cell line from a patient whose disease had evolved from stage 4s to 4, without evidence of deletion of the short arm of chromosome 1 and MYCN amplification, which are considered the most typical genetic indicators of aggressive disease. The cytogenetic study allowed a full characterization of the chromosome changes, and revealed a complex translocation of chromosome 17 leading to a derivative marker which may be described as follows: der(11)t(11;17)(p15;q12)t(11;17) (q22;q12). This resulted in a gain of part of the long arms of chromosome 17, which was recently associated with poor prognosis.


Assuntos
Cromossomos Humanos Par 17 , Neuroblastoma/genética , Translocação Genética/genética , Células Tumorais Cultivadas/patologia , Animais , Imunofluorescência , Humanos , Hibridização in Situ Fluorescente , Recém-Nascido , Cariotipagem , Masculino , Camundongos , Camundongos Nus , Transplante de Neoplasias , Neuroblastoma/patologia
17.
Cancer Genet Cytogenet ; 99(1): 77-80, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9352800

RESUMO

We report a case of Ph-positive chronic myelocytic leukemia in blastic phase in an 11-year-old boy with Down syndrome. Monosomy 7 was the only additional chromosomal anomaly in the blastic clone. Fluorescence in situ hybridization analysis on interphase nuclei with a centromeric probe specific to chromosome 7 proved to be efficient in disease monitoring, and showed, together with the results of chromosome analysis on metaphases, that B-lymphocytes at the origin of an EBV-established line were not part of the leukemic clone. The study of DNA polymorphisms showed that the origin of the constitutional trisomy 21 was a maternal anaphase I nondisjunction, that the chromosome 7 lost in the blastic marrow clone was the maternal one, and led us to postulate that the mother's chromosomes are prone to impairment of normal disjunction. The study of allelic losses of chromosome 7 loci proved to be a further possibility for disease monitoring.


Assuntos
Cromossomos Humanos Par 7 , Síndrome de Down/complicações , Síndrome de Down/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Monossomia , Adulto , Criança , Feminino , Humanos , Hibridização in Situ Fluorescente , Masculino , Polimorfismo Genético , Gravidez
18.
Haematologica ; 82(6): 654-9, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9499663

RESUMO

BACKGROUND AND OBJECTIVE: Cytogenetic analysis of acute leukemia yields important information which has been demonstrated to be correlated to patient survival. A reference laboratory was created in order to perform karyotype analysis on all cases of acute leukemia enrolled in the AIEOP (Associazione Italiana Emato-Oncologia Pediatrica) protocols. METHODS: From January 1990 to December 1995, 1115 samples of children with ALL or AML were sent in for cytogenetic analysis. The results of cell cultures were screened in the Reference Laboratory and then the fixed metaphases were sent to one of the six cytogenetic laboratories for analysis. RESULTS: The leukemic karyotypes of 556 patients were successfully analyzed. An abnormal clone was detected in 49% of cases of ALL and in 66% of AML. In ALL the most frequent abnormality was 9p rearrangement. Other recurrent abnormalities were t(9;22), t(4;11) and t(1;19). In AML t(8;21), t(15;17) and 11q23 rearrangement were the most frequent structural abnormalities. These findings are similar to the results obtained in other multicenter studies using a similar approach. INTERPRETATION AND CONCLUSIONS: Our data confirm the feasibility of performing cytogenetic analysis in a centralized laboratory on mailed samples of bone marrow and/or peripheral blood; this is very important considering that cytogenetic analysis of neoplastic tissue requires a special laboratory and expert staff.


Assuntos
Serviços Centralizados no Hospital , Leucemia Mieloide/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Doença Aguda , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Itália , Cariotipagem , Masculino
19.
Genes Chromosomes Cancer ; 17(2): 94-101, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8913726

RESUMO

Three patients, with constitutional trisomy 8 mosaicism (CT8M), who developed a malignancy are reported. The diagnoses were refractory anaemia, acute lymphoblastic leukaemia, and idiopathic myelofibrosis. In the child with acute leukaemia, the CT8M was diagnosed at birth due to severe dysmorphisms and malformations; the other two patients showed a milder phenotype, and the CT8M was diagnosed only after the finding of trisomy 8 in neoplastic cells. The review of eight similar, previously reported cases and the clinical, cytogenetic, and molecular studies performed in our patients led us to make the following observations: (I) CT8M predisposes to neoplasms, preferentially to myelo- or lymphoproliferative diseases; (2) a gene dosage effect for glutathione reductase in red blood cells was seen in two of our patients; (3) the wide phenotypic variation of CT8M was confirmed: trisomy 8 in neoplastic cells of phenotypically near-normal cases may be misinterpreted as acquired; and (4) molecular studies suggested a postzygotic origin of the trisomy in our three cases, with the supernumerary chromosome being of paternal origin in one case and of maternal origin in the other two. We postulate that the trisomy 8 in neoplasms may often occur by mitotic nondisjunction in an early embryonic multipotent cell and that what is usually interpreted as an acquired trisomy 8 may in fact be CT8M. The constitutional trisomy 8 would act as a pathogenetically important first mutation in multistep carcinogenesis. Whenever trisomy 8 is found in malignancies, the patient should be reevaluated clinically to exclude CT8M, and CT8M patients should be monitored for the possible development of malignancies.


Assuntos
Anemia Refratária/genética , Cromossomos Humanos Par 8 , Neoplasias Hematológicas/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Mielofibrose Primária/genética , Trissomia , Anemia Refratária/enzimologia , Ácido Aspártico Endopeptidases/genética , Pré-Escolar , Cromossomos Humanos Par 8/genética , Feminino , Fibroblastos/citologia , Glutationa Redutase/genética , Humanos , Lactente , Cariotipagem , Malato Desidrogenase/genética , Masculino , Mosaicismo , Mutação , Reação em Cadeia da Polimerase , Leucemia-Linfoma Linfoblástico de Células Precursoras/enzimologia , Mielofibrose Primária/enzimologia , Trissomia/genética
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