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1.
Sci Rep ; 14(1): 17187, 2024 Jul 26.
Article in English | MEDLINE | ID: mdl-39060302

ABSTRACT

Germline TP53 pathogenic variants can lead to a cancer susceptibility syndrome known as Li-Fraumeni (LFS). Variants affecting its activity can drive tumorigenesis altering p53 pathways and their identification is crucial for assessing individual risk. This study explored the functional impact of TP53 missense variants on its transcription factor activity. We selected seven TP53 missense variants (c.129G > C, c.320A > G, c.417G > T, c.460G > A, c,522G > T, c.589G > A and c.997C > T) identified in Brazilian families at-risk for LFS. Variants were created through site-directed mutagenesis and transfected into SK-OV-3 cells to assess their transcription activation capabilities. Variants K139N and V197M displayed significantly reduced transactivation activity in a TP53-dependent luciferase reporter assay. Additionally, K139N negatively impacted CDKN1A and MDM2 expression and had a limited effect on GADD45A and PMAIP1 upon irradiation-induced DNA damage. Variant V197M demonstrated functional impact in all target genes evaluated and loss of Ser15 phosphorylation. K139N and V197M variants presented a reduction of p21 levels after irradiation. Our data show that K139N and V197M negatively impact p53 functions, supporting their classification as pathogenic variants. This underscores the significance of conducting functional studies on germline TP53 missense variants classified as variants of uncertain significance to ensure proper management of LFS-related cancer risks.


Subject(s)
Genetic Predisposition to Disease , Germ-Line Mutation , Li-Fraumeni Syndrome , Mutation, Missense , Tumor Suppressor Protein p53 , Li-Fraumeni Syndrome/genetics , Humans , Tumor Suppressor Protein p53/genetics , Brazil , Proto-Oncogene Proteins c-mdm2/genetics , Female , Cyclin-Dependent Kinase Inhibitor p21/genetics , Male , Cell Cycle Proteins/genetics , Cell Line, Tumor , Transcriptional Activation/genetics , GADD45 Proteins
2.
RSC Adv ; 14(13): 8981-8989, 2024 Mar 14.
Article in English | MEDLINE | ID: mdl-38495993

ABSTRACT

Research into innovative food safety technologies has led to the development of smart packaging with embedded chemical sensors that can monitor food quality throughout the supply chain. Thermochromic materials (TM), which are able to dynamically change colour in response to temperature fluctuations, have proven to be reliable indicators of food quality in certain environments. Natural colourants such as curcumin are becoming increasingly popular for smart packaging due to their low toxicity, environmental friendliness and ability to change colour. The innovation in this research lies in the production of a bio-based bilayer membrane specifically designed for irreversible temperature monitoring. Membrane A was prepared by dissolving cellulose acetate and curcumin in acetone at room temperature, with glycerol serving as a plasticiser. At the same time, membrane B was carefully formulated by dissolving cellulose acetate and triethanolamine in acetone, with sorbitol as plasticiser. The preparation of these different membranes revealed a remarkable event: a gradual and irreversible colour transition from an initial yellow to a brick-red hue after 24 hours of storage at 25 °C. The chemical structure and morphological analyses of the membranes were performed using several techniques, including FTIR, DSC and SEM. The membrane labels were adhered to aluminium cans and their colorimetric response was observed over a period of 10 days. Minimal colour variations were observed, confirming the reproducibility and stability of the curcumin-based membranes as temperature sensors.

3.
Curr Cancer Drug Targets ; 23(11): 900-909, 2023.
Article in English | MEDLINE | ID: mdl-37076963

ABSTRACT

BACKGROUND: Breast and ovarian tumors with pathogenic variants in BRCA1 or BRCA2 genes are more sensitive to poly (ADP-ribose) polymerase inhibitors (PARPi) treatment than wildtype tumors. Pathogenic variants in non-BRCA1/2 homologous recombination repair genes (HRR) also concede sensitivity to PARPi treatment. RAD50 participates in the Mre11-RAD50-Nbn (MRN) complex of the HRR pathway and plays an important role in DNA repair. OBJECTIVE: The objective of this study is to evaluate whether RAD50 protein deficiency modulates the PARPi response in breast cancer cell lines. METHODS: T47D breast cancer cell line was modified using small interfering RNA and CRISPR/Cas9 technology, to knockout the RAD50 gene. PARPi response (niraparib, olaparib and rucaparib alone or in combination with carboplatin), in T47D and T47D-edited clones, was evaluated by cell viability, cell cycle, apoptosis and protein expression analyses. RESULTS: Treatment with niraparib and carboplatin exerted a synergistic effect on T47D-RAD50 deficient cells and an antagonistic effect on T47D cells parental. Cell cycle analysis demonstrated an increase in the G2/M population in cells treated with niraparib or rucaparib alone or in combination with carboplatin. T47D-RAD50 deficient cells treated with rucaparib and carboplatin exhibited twofold levels in late apoptosis, also showing differences in PARP activation. All T47D RAD50 deficient clones treated with niraparib or rucaparib combined with carboplatin, or rucaparib alone showed increased levels of H2AX phosphorylation. CONCLUSIONS: T47D RAD50 deficient cells treated with PARP inhibitors alone or in combination with carboplatin showed cell cycle arrest in the G2/M phase, leading to death by apoptosis. Thus, RAD50 deficiency may be a good biomarker for predicting PARPi response.


Subject(s)
Breast Neoplasms , Ovarian Neoplasms , Female , Humans , Poly(ADP-ribose) Polymerase Inhibitors/pharmacology , Poly(ADP-ribose) Polymerase Inhibitors/therapeutic use , Carboplatin/pharmacology , Carboplatin/therapeutic use , Breast Neoplasms/drug therapy , Breast Neoplasms/genetics , DNA Repair , Ovarian Neoplasms/drug therapy
4.
Psicol Reflex Crit ; 35(1): 4, 2022 Jan 04.
Article in English | MEDLINE | ID: mdl-34982275

ABSTRACT

BACKGROUND: The influence of education on cognition has been extensively researched, particularly in countries with high levels of illiteracy. However, the impact of low education in all cognitive functions appears to differ. Regarding to language, the effects of education on many linguistic tasks-supported by different processing-remain unclear. The primary objective of this study was to determine whether oral language task performance differs among individuals with no formal and low-educated subjects, as measured by the Brazilian Montreal-Toulouse Language Assessment Battery (MTL-BR). This is the only language battery available for use in Brazil, but lacks normative data for illiterate individuals. The secondary objective was to gather data for use as clinical parameters in assessing persons with aphasia (PWA) not exposed to a formal education. METHODS: A total of 30 healthy illiterate individuals aged 34-60 years were assessed. All participants underwent the MTL-BR Battery, excluding its written communication tasks. The data obtained in the present study were compared against results of a previous investigation of individuals with 1-4 years of education evaluated using the same MTL-BR instrument. RESULTS: Statistically significant differences in performance were found between non-formal education and the low-educated (2-4 years) groups on the tasks Auditory Comprehension, Repetition, Orthographic/Phonological Fluency, Number dictation, Reading of numbers and also on simple numerical calculations. CONCLUSION: The study results showed that individuals with no formal education/illiterate had worse performance than low-education individuals on some of the language tasks of the MTL-Br Battery, suggesting that each year of education impacts cognitive-language performance. Also, data were obtained which can serve as a guide for PWA not exposed to a formal education.

5.
Psicol. reflex. crit ; 35: 4, 2022. tab
Article in English | LILACS, Index Psychology - journals | ID: biblio-1360651

ABSTRACT

Background: The influence of education on cognition has been extensively researched, particularly in countries with high levels of illiteracy. However, the impact of low education in all cognitive functions appears to differ. Regarding to language, the effects of education on many linguistic tasks-supported by different processing-remain unclear. The primary objective of this study was to determine whether oral language task performance differs among individuals with no formal and low-educated subjects, as measured by the Brazilian Montreal-Toulouse Language Assessment Battery (MTL-BR). This is the only language battery available for use in Brazil, but lacks normative data for illiterate individuals. The secondary objective was to gather data for use as clinical parameters in assessing persons with aphasia (PWA) not exposed to a formal education. Methods: A total of 30 healthy illiterate individuals aged 34-60 years were assessed. All participants underwent the MTL-BR Battery, excluding its written communication tasks. The data obtained in the present study were compared against results of a previous investigation of individuals with 1-4 years of education evaluated using the same MTL-BR instrument. Results: Statistically significant differences in performance were found between non-formal education and the low-educated (2-4 years) groups on the tasks Auditory Comprehension, Repetition, Orthographic/Phonological Fluency, Number dictation, Reading of numbers and also on simple numerical calculations. Conclusion: The study results showed that individuals with no formal education/illiterate had worse performance than low-education individuals on some of the language tasks of the MTL-Br Battery, suggesting that each year of education impacts cognitive-language performance. Also, data were obtained which can serve as a guide for PWA not exposed to a formal education. (AU)


Subject(s)
Humans , Male , Female , Adolescent , Adult , Middle Aged , Cognition , Educational Status , Language , Education
6.
Neuron ; 106(1): 37-65.e5, 2020 04 08.
Article in English | MEDLINE | ID: mdl-32027825

ABSTRACT

The Cre-loxP system is invaluable for spatial and temporal control of gene knockout, knockin, and reporter expression in the mouse nervous system. However, we report varying probabilities of unexpected germline recombination in distinct Cre driver lines designed for nervous system-specific recombination. Selective maternal or paternal germline recombination is showcased with sample Cre lines. Collated data reveal germline recombination in over half of 64 commonly used Cre driver lines, in most cases with a parental sex bias related to Cre expression in sperm or oocytes. Slight differences among Cre driver lines utilizing common transcriptional control elements affect germline recombination rates. Specific target loci demonstrated differential recombination; thus, reporters are not reliable proxies for another locus of interest. Similar principles apply to other recombinase systems and other genetically targeted organisms. We hereby draw attention to the prevalence of germline recombination and provide guidelines to inform future research for the neuroscience and broader molecular genetics communities.


Subject(s)
Gene Targeting/methods , Integrases/genetics , Neurons/metabolism , Oocytes/metabolism , Recombination, Genetic/genetics , Spermatozoa/metabolism , Animals , Female , Genes, Reporter , Germ Cells , Male , Mice , Mice, Transgenic , Mosaicism
7.
Diabetes Res Clin Pract ; 138: 262-270, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29412146

ABSTRACT

AIMS: To evaluate the predictive factors of birth weight (BW) of newborns of women with gestational diabetes mellitus (GDM). METHODS: A cross-sectional study was performed among pregnant women with GDM treated in a public maternity unit, Brazil. We selected 283 pregnant women, with nutritional follow-up initiated till the 28th gestational week, singleton pregnancy, without chronic diseases and with birth weight information of the newborns. The predictive factors of BW were identified by multivariate linear regression. RESULTS: Mean maternal age was 31.2 ±â€¯5.8 years; 64.4% were non-white; 70.1% were pre-gestational overweight or obese. Mean BW was 3234.3 ±â€¯478.8 g. An increase of 1 kg of weight in the first and third trimesters increased BW by 21 g (p = 0.01) and 27 g (p = 0.03), respectively. Similarly, the other predictive factors of BW were pre-gestational body mass index (ß = 17.16, p = 0.02) and postprandial plasma glucose in the third trimester (ß = 4.14, p = 0.008), in the model adjusted by gestational age at delivery (ß = 194.68, p < 0.001). CONCLUSIONS: The best predictors of BW were gestational age at birth, and maternal pre-gestational and gestational anthropometric characteristics. Maternal glycaemic levels may also influence BW. The results may contribute to a review of prenatal routines for pregnant women with GDM.


Subject(s)
Birth Weight , Diabetes, Gestational/diagnosis , Pregnancy Outcome , Adult , Brazil/epidemiology , Cross-Sectional Studies , Diabetes, Gestational/epidemiology , Female , Gestational Age , Humans , Infant, Newborn , Mothers , Pregnancy , Pregnancy Outcome/epidemiology , Pregnancy Trimester, Third , Prognosis , Young Adult
8.
Article in English | MEDLINE | ID: mdl-28798905

ABSTRACT

Classical treatment for congenital toxoplasmosis is based on combination of sulfadiazine and pyrimethamine plus folinic acid. Due to teratogenic effects and bone marrow suppression caused by pyrimethamine, the establishment of new therapeutic strategies is indispensable to minimize the side effects and improve the control of infection. Previous studies demonstrated that enrofloxacin and toltrazuril reduced the incidence of Neospora caninum and Toxoplasma gondii infection. The aim of the present study was to evaluate the efficacy of enrofloxacin and toltrazuril in the control of T. gondii infection in human trophoblast cells (BeWo line) and in human villous explants from the third trimester. BeWo cells and villous were treated with several concentrations of enrofloxacin, toltrazuril, sulfadiazine, pyrimethamine, or combination of sulfadiazine+pyrimethamine, and the cellular or tissue viability was verified. Next, BeWo cells were infected by T. gondii (2F1 clone or the ME49 strain), whereas villous samples were only infected by the 2F1 clone. Then, infected cells and villous were treated with all antibiotics and the T. gondii intracellular proliferation as well as the cytokine production were analyzed. Finally, we evaluated the direct effect of enrofloxacin and toltrazuril in tachyzoites to verify possible changes in parasite structure. Enrofloxacin and toltrazuril did not decrease the viability of cells and villous in lower concentrations. Both drugs were able to significantly reduce the parasite intracellular proliferation in BeWo cells and villous explants when compared to untreated conditions. Regardless of the T. gondii strain, BeWo cells infected and treated with enrofloxacin or toltrazuril induced high levels of IL-6 and MIF. In villous explants, enrofloxacin induced high MIF production. Finally, the drugs increased the number of unviable parasites and triggered damage to tachyzoite structure. Taken together, it can be concluded that enrofloxacin and toltrazuril are able to control T. gondii infection in BeWo cells and villous explants, probably by a direct action on the host cells and parasites, which leads to modifications of cytokine release and tachyzoite structure.


Subject(s)
Antiprotozoal Agents/metabolism , Fluoroquinolones/metabolism , Placenta/parasitology , Toxoplasma/drug effects , Toxoplasma/growth & development , Triazines/metabolism , Trophoblasts/parasitology , Cell Line , Cell Survival/drug effects , Cytokines/metabolism , Enrofloxacin , Female , Humans , Organ Culture Techniques , Parasite Load , Pregnancy , Toxoplasma/cytology
9.
J Neurophysiol ; 113(4): 1085-99, 2015 Feb 15.
Article in English | MEDLINE | ID: mdl-25429122

ABSTRACT

In the diabetic retina, cellular changes in the retinal pigment epithelium (RPE) and neurons occur before vision loss or diabetic retinopathy can be identified clinically. The precise etiologies of retinal pathology are poorly defined, and it remains unclear if the onset and progression of cellular dysfunction differ between type 1 and type 2 diabetes. Three mouse models were used to compare the time course of RPE involvement in type 1 and type 2 diabetes. C57BL/6J mice injected with streptozotocin (STZ mice) modeled type 1 diabetes, whereas Lepr(db/db) mice on both BKS and B6.BKS background strains modeled type 2 diabetes. Electroretinogram (ERG)-based techniques were used to measure light-evoked responses of the RPE (direct current-coupled ERG, dc-ERG) and the neural retina (a-wave, b-wave). Following onset of hyperglycemia, a-wave and b-wave amplitudes of STZ mice declined progressively and by equivalent degrees. Components of the dc-ERG were also altered, with the largest reduction seen in the c-wave. Lepr(db/db) mice on the BKS strain (BKS.Lepr) displayed sustained hyperglycemia and a small increase in insulin, whereas Lepr(db/db) mice on the B6.BKS background (B6.BKS.Lepr) were transiently hyperglycemic and displayed severe hyperinsulinemia. BKS.Lepr mice exhibited sustained reductions in the dc-ERG c-wave, fast oscillation, and off response that were not attributable to reduced photoreceptor activity; B6.BKS.Lepr mice displayed transient reductions in the c-wave and fast oscillation that correlated with hyperglycemia and magnitude of photoreceptor activity. In summary, all mouse models displayed altered RPE function concomitant with the onset of hyperglycemia. These results suggest that RPE function is directly reduced by elevated blood glucose levels. That RPE dysfunction was reversible and mitigated in hyperinsulinemic B6.BKS.Lepr mice provides insight into the underlying mechanism.


Subject(s)
Diabetes Mellitus, Experimental/physiopathology , Diabetic Retinopathy/physiopathology , Hyperglycemia/physiopathology , Retinal Pigment Epithelium/physiopathology , Action Potentials , Animals , Diabetic Retinopathy/genetics , Mice , Mice, Inbred C57BL , Receptors, Leptin/genetics
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