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BACKGROUND: SARS-CoV2 induces flu-like symptoms that can rapidly progress to severe acute lung injury and even death. The virus also invades the central nervous system (CNS), causing neuroinflammation and death from central failure. Intravenous (IV) or oral dexamethasone (DXM) reduced 28 d mortality in patients who required supplemental oxygen compared to those who received conventional care alone. Through these routes, DMX fails to reach therapeutic levels in the CNS. In contrast, the intranasal (IN) route produces therapeutic levels of DXM in the CNS, even at low doses, with similar systemic bioavailability. AIMS: To compare IN vs. IV DXM treatment in hospitalized patients with COVID-19. METHODS: A controlled, multicenter, open-label trial. Patients with COVID-19 (69) were randomly assigned to receive IN-DXM (0.12 mg/kg for three days, followed by 0.6 mg/kg for up to seven days) or IV-DXM (6 mg/d for 10 d). The primary outcome was clinical improvement, as defined by the National Early Warning Score (NEWS) ordinal scale. The secondary outcome was death at 28 d between IV and IN patients. Effects of both treatments on biochemical and immunoinflammatory profiles were also recorded. RESULTS: Initially, no significant differences in clinical severity, biometrics, and immunoinflammatory parameters were found between both groups. The NEWS-2 score was reduced, in 23 IN-DXM treated patients, with no significant variations in the 46 IV-DXM treated ones. Ten IV-DXM-treated patients and only one IN-DXM patient died. CONCLUSIONS: IN-DMX reduced NEWS-2 and mortality more efficiently than IV-DXM, suggesting that IN is a more efficient route of DXM administration.
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COVID-19 , Humanos , SARS-CoV-2 , RNA Viral , Tratamento Farmacológico da COVID-19 , Dexametasona/uso terapêuticoRESUMO
INTRODUCTION: Patients with cervical cancer (CC) may experience local recurrence very often after treatment; when only clinical parameters are used, most cases are diagnosed in late stages, which decreases the chance of recovery. Molecular markers can improve the prediction of clinical outcome. Glycolysis is altered in 70% of CCs, so molecular markers of this pathway associated with the aggressiveness of CC can be identified. METHODS: The expression of 14 glycolytic genes was analyzed in 97 CC and 29 healthy cervical tissue (HCT) with microarray; only LDHA and PFKP were validated at the mRNA and protein levels in 36 of those CC samples and in 109 new CC samples, and 31 HCT samples by qRT-PCR, Western blotting, or immunohistochemistry. A replica analysis was performed on 295 CC from The Cancer Genome Atlas (TCGA) database. RESULTS: The protein expression of LDHA and PFKP was associated with poor overall survival [OS: LDHA HR = 4.0 (95% CI = 1.4-11.1); p = 8.0 × 10-3 ; PFKP HR = 3.3 (95% CI = 1.1-10.5); p = 4.0 × 10-2 ] and disease-free survival [DFS: LDHA HR = 4.5 (95% CI = 1.9-10.8); p = 1.0 × 10-3 ; PFKP HR = 3.2 (95% CI = 1.2-8.2); p = 1.8 × 10-2 ] independent of FIGO clinical stage, and the results for mRNA expression were similar. The risk of death was greater in patients with overexpression of both biomarkers than in patients with advanced FIGO stage [HR = 8.1 (95% CI = 2.6-26.1; p = 4.3 × 10-4 ) versus HR = 7 (95% CI 1.6-31.1, p = 1.0 × 10-2 )] and increased exponentially as the expression of LDHA and PFKP increased. CONCLUSIONS: LDHA and PFKP overexpression at the mRNA and protein levels was associated with poor OS and DFS and increased risk of death in CC patients regardless of FIGO stage. The measurement of these two markers could be very useful for evaluating clinical evolution and the risk of death from CC and could facilitate better treatment decision making.
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Fosfofrutoquinases , Neoplasias do Colo do Útero , Feminino , Humanos , Biomarcadores/metabolismo , Glicólise/genética , L-Lactato Desidrogenase/genética , L-Lactato Desidrogenase/metabolismo , Lactato Desidrogenase 5/metabolismo , Fosfofrutoquinases/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Neoplasias do Colo do Útero/genéticaRESUMO
BACKGROUND: By end December of 2021, COVID-19 has infected around 276 million individuals and caused over 5 million deaths worldwide. Infection results in dysregulated systemic inflammation, multi-organ dysfunction, and critical illness. Cells of the central nervous system are also affected, triggering an uncontrolled neuroinflammatory response. Low doses of glucocorticoids, administered orally or intravenously, reduce mortality among moderate and severe COVID-19 patients. However, low doses administered by these routes do not reach therapeutic levels in the CNS. In contrast, intranasally administered dexamethasone can result in therapeutic doses in the CNS even at low doses. METHODS: This is an approved open-label, multicenter, randomized controlled trial to compare the effectiveness of intranasal versus intravenous dexamethasone administered in low doses to moderate and severe COVID-19 adult patients. The protocol is conducted in five health institutions in Mexico City. A total of 120 patients will be randomized into two groups (intravenous vs. intranasal) at a 1:1 ratio. Both groups will be treated with the corresponding dexamethasone scheme for 10 days. The primary outcome of the study will be clinical improvement, defined as a statistically significant reduction in the NEWS-2 score of patients with intranasal versus intravenous dexamethasone administration. The secondary outcome will be the reduction in mortality during hospitalization. CONCLUSIONS: This protocol is currently in progress to improve the efficacy of the standard therapeutic dexamethasone regimen for moderate and severe COVID-19 patients. TRIAL REGISTRATION: ClinicalTrials.gov NCT04513184 . Registered November 12, 2020. Approved by La Comisión Federal para la Protección contra Riesgos Sanitarios (COFEPRIS) with identification number DI/20/407/04/36. People are currently being recruited.
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Tratamento Farmacológico da COVID-19 , Dexametasona/efeitos adversos , Humanos , Inflamação , Doenças Neuroinflamatórias , SARS-CoV-2 , Resultado do TratamentoRESUMO
Matrix stiffness is a central regulator of fibroblast function. However, the transcriptional mechanisms linking matrix stiffness to changes in fibroblast phenotype are incompletely understood. Here, we evaluated the effect of matrix stiffness on genome-wide chromatin accessibility in freshly isolated lung fibroblasts using ATAC-seq. We found higher matrix stiffness profoundly increased global chromatin accessibility relative to lower matrix stiffness, and these alterations were in close genomic proximity to known profibrotic gene programs. Motif analysis of these regulated genomic loci identified ZNF416 as a putative mediator of fibroblast stiffness responses. Genome occupancy analysis using ChIP-seq confirmed that ZNF416 occupies a broad range of genes implicated in fibroblast activation and tissue fibrosis, with relatively little overlap in genomic occupancy with other mechanoresponsive and profibrotic transcriptional regulators. Using loss- and gain-of-function studies, we demonstrated that ZNF416 plays a critical role in fibroblast proliferation, extracellular matrix synthesis, and contractile function. Together, these observations identify ZNF416 as novel mechano-activated transcriptional regulator of fibroblast biology.
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Fibroblastos/fisiologia , Regulação da Expressão Gênica/genética , Transcrição Gênica/genética , Animais , Proliferação de Células/genética , Células Cultivadas , Cromatina/genética , Matriz Extracelular/genética , Fibrose/genética , Genoma/genética , Pulmão/fisiologia , Camundongos , Camundongos Transgênicos , FenótipoRESUMO
Voltage-gated sodium (NaV) channels have been related with cell migration and invasiveness in human cancers. We previously reported the contribution of NaV1.6 channels activity with the invasion capacity of cervical cancer (CeCa) positive to Human Papilloma Virus type 16 (HPV16), which accounts for 50% of all CeCa cases. Here, we show that NaV1.6 gene (SCN8A) overexpression is a general characteristic of CeCa, regardless of the HPV type. In contrast, no differences were observed in NaV1.6 channel expression between samples of non-cancerous and cervical intraepithelial neoplasia. Additionally, we found that CeCa cell lines, C33A, SiHa, CaSki and HeLa, express mainly the splice variant of SCN8A that lacks exon 18, shown to encode for an intracellularly localized NaV1.6 channel, whereas the full-length adult form was present in CeCa biopsies. Correlatively, patch-clamp experiments showed no evidence of whole-cell sodium currents (INa) in CeCa cell lines. Heterologous expression of full-length NaV1.6 isoform in C33A cells produced INa, which were sufficient to significantly increase invasion capacity and matrix metalloproteinase type 2 (MMP-2) activity. These data suggest that upregulation of NaV1.6 channel expression occurs when cervical epithelium have been transformed into cancer cells, and that NaV1.6-mediated invasiveness of CeCa cells involves MMP-2 activity. Thus, our findings support the notion about using NaV channels as therapeutic targets against cancer metastasis.
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Papillomavirus Humano 16/isolamento & purificação , Metaloproteinase 2 da Matriz/metabolismo , Canal de Sódio Disparado por Voltagem NAV1.6/metabolismo , Invasividade Neoplásica , Neoplasias do Colo do Útero/fisiopatologia , Linhagem Celular Tumoral , Feminino , Perfilação da Expressão Gênica , Humanos , Metaloproteinase 2 da Matriz/genética , Canal de Sódio Disparado por Voltagem NAV1.6/genética , Técnicas de Patch-ClampRESUMO
The cyclin-dependent kinase inhibitor 3 (CDKN3) gene, involved in mitosis, is upregulated in cervical cancer (CC). We investigated CDKN3 mRNA as a survival biomarker and potential therapeutic target for CC. CDKN3 mRNA was measured in 134 CC and 25 controls by quantitative PCR. A 5-year survival study was conducted in 121 of these CC patients. Furthermore, CDKN3-specific siRNAs were used to investigate whether CDKN3 is involved in proliferation, migration, and invasion in CC-derived cell lines (SiHa, CaSki, HeLa). CDKN3 mRNA was on average 6.4-fold higher in tumors than in controls (p = 8 x 10-6, Mann-Whitney). A total of 68.2% of CC patients over expressing CDKN3 gene (fold change ≥ 17) died within two years of diagnosis, independent of the clinical stage and HPV type (Hazard Ratio = 5.0, 95% CI: 2.5-10, p = 3.3 x 10-6, Cox proportional-hazards regression). In contrast, only 19.2% of the patients with lower CDKN3 expression died in the same period. In vitro inactivation of CDKN3 decreased cell proliferation on average 67%, although it had no effect on cell migration and invasion. CDKN3 mRNA may be a good survival biomarker and potential therapeutic target in CC.
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Biomarcadores Tumorais/genética , Proteínas Inibidoras de Quinase Dependente de Ciclina/genética , Proteínas Inibidoras de Quinase Dependente de Ciclina/metabolismo , Fosfatases de Especificidade Dupla/genética , Fosfatases de Especificidade Dupla/metabolismo , Terapia de Alvo Molecular , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/genética , Sequência de Bases , Carcinogênese , Movimento Celular , Proliferação de Células , Regulação para Baixo , Feminino , Regulação Neoplásica da Expressão Gênica , Células HeLa , Humanos , Pessoa de Meia-Idade , Invasividade Neoplásica , Estadiamento de Neoplasias , Papillomaviridae/fisiologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/genética , Análise de Sobrevida , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/virologiaRESUMO
INTRODUCTION: The cyclin-dependent kinase inhibitor 3 gene (CDKN3), which is involved in mitosis, has been found upregulated and associated with low survival in cervical cancer (CC) patients. Therefore, as in other cancers, CDKN3 could be a potential target in CC. AREAS COVERED: In this review, the authors analyzed the evidence supporting the upregulation of CDKN3 in CC, its role in mitosis and the cell cycle, the evidence that CDKN3 may be useful as marker for survival and selection of CC patients for additional chemotherapy or specific target cancer therapy, the data supporting the role of CDKN3 in cell proliferation, and how CDKN3 targeting with specific small interfering RNA (siRNAs) suppress cell proliferation of cell lines derived from CC and other cancers. Finally, we discuss if the upregulation of CDKN3 can be part of the human papilloma virus strategy to avoid the mitosis checkpoint, the research to find small specific drugs to target CDKN3 and the advantages that CDKN3 has as target for novel drug design for CC treatment. EXPERT OPINION: CDKN3 might be useful not only as marker for survival and selection of CC patients for additional chemotherapy or specific target cancer therapy, but also as a potential target to develop specific small drugs to combat CC.
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Antineoplásicos/farmacologia , Proteínas Inibidoras de Quinase Dependente de Ciclina/genética , Fosfatases de Especificidade Dupla/genética , Neoplasias do Colo do Útero/tratamento farmacológico , Animais , Proliferação de Células/genética , Desenho de Fármacos , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Mitose/fisiologia , Terapia de Alvo Molecular , Taxa de Sobrevida , Regulação para Cima , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/patologiaRESUMO
We investigated the role of tumor copy number (CN)-altered genome (CN-AG) in the carcinogenesis of cervical cancer (CC), especially its effect on gene expression, biological processes, and patient survival. Fifty-nine human papillomavirus 16 (HPV16)-positive CCs were investigated with microarrays-31 for mapping CN-AG and 55 for global gene expression, with 27 CCs in common. Five-year survival was investigated in 55 patients. Deletions and amplifications >2.5 Mb were defined as CN alterations. The %CN-AG varied from 0 to 32.2% (meanâ=â8.1±8.9). Tumors were classified as low (meanâ=â0.5±0.6, nâ=â11), medium (meanâ=â5.4±2.4, nâ=â10), or high (meanâ=â19.2±6.6, nâ=â10) CN. The highest %CN-AG was found in 3q, which contributed an average of 55% of all CN alterations. Genome-wide, only 5.3% of CN-altered genes were deregulated directly by gene dosage. In contrast, the rate in fully duplicated 3q was twice as high. Amplification of 3q explained 23.2% of deregulated genes in whole tumors (r2â=â0.232, pâ=â0.006; analysis of variance), including genes located in 3q and other chromosomes. A total of 862 genes were deregulated exclusively in high-CN tumors, but only 22.9% were CN altered. This suggests that the remaining genes are not deregulated directly by gene dosage, but by mechanisms induced in trans by CN-altered genes. Anaphase-promoting complex/cyclosome (APC/C)-dependent proteasome proteolysis, glycolysis, and apoptosis were upregulated, whereas cell adhesion and angiogenesis were downregulated exclusively in high-CN tumors. The high %CN-AG and upregulated gene expression profile of APC/C-dependent proteasome proteolysis were associated with poor patient survival (p<0.05, log-rank test). Along with glycolysis, they were linearly associated with FIGO stage (r>0.38, p<0.01, Spearman test). Therefore, inhibition of APC/C-dependent proteasome proteolysis and glycolysis could be useful for CC treatment. However, whether they are indispensable for tumor growth remains to be demonstrated.
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Dosagem de Genes , Perfilação da Expressão Gênica , Genômica , Neoplasias do Colo do Útero/genética , Adulto , Idoso , Carcinogênese/genética , Cromossomos Humanos/genética , Feminino , Seguimentos , Genes Neoplásicos/genética , Papillomavirus Humano 16/fisiologia , Humanos , Pessoa de Meia-Idade , Análise de Sobrevida , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/virologia , Adulto JovemRESUMO
Resumen Objetivo: Describir el comportamiento de los resultados obtenidos en distintas pruebas de eva luación de Teoría de la Mente (Test de expresiones faciales, Test de Sally y Ann, Historias extrañas de Happé y Faux Pas) y el Test Coeficiente de Empatía y Sistematización para niños de 4 a 11 años de Baron-Cohen; además pretendió determinar si existía una correlación entre los constructos de Teoría de la Mente y Empatía. Método: De tipo cuantitativo, empírico-analítico, exploratorio-descriptivo y de campo, donde se tomó como muestra para el grupo de casos a 8 niños y 2 niñas, en tre los 7 y los 11 años de edad, diagnosticado(a)s con síndrome de Asperger, asistentes a procesos terapéuticos en un Instituto de Desarrollo Integral, mientras que para el grupo control seleccionó a 8 niños y 2 niñas de una Institución educativa pública de Manizales, no diagnosticado(a)s con síndrome de Asperger, equiparados con el grupo de casos respecto a género y edad; ambos grupos contaron con el respectivo consentimiento informado de sus padres o acudientes legales. El análi sis estadístico se realizó a través de las pruebas U de Mann Whitneyy Chi-Cuadrado. Resultados: Corroboraron diferencias poblacionales en las pruebas, donde el grupo control obtuvo mejores puntajes que el grupo de casos en general; sin embargo no fue posible encontrar una correlación entre la Teoría de la Mente y la Empatía. Conclusión: Se sugieren nuevas investigaciones con muestras de mayor tamaño para evitar la dispersión de los datos.
Abstract Objective: Compare the behavior of the results obtained in the different tests of theory of mind (Facial Expressions Test, Sally Anne Test, Happe's strange stories tasks and Faux Pas Test) and the coefficient Test of empathy and systematization for children 4 to 11 years by Baron-Cohen; Also was intended to determine if there is a correlation between both constructs. Method: Empirical- analytic, exploratory-descriptive and of field, it took as sample for the group of cases to 8 boys and 2 girls, betwen 7 and 11 years old, diagnosed with Asperger syndrome, assistants to thera peutic processes in an Institute of Integral development, while for the control group were took to 8 boys and 2 girls from a public educational Institution of Manizales, without the diagnostic of Asperger syndrome, matched with the group of cases respect to gender and age; both groups had the respective informed condense from their parents or their legal assistants. The statistical analysis was made with U de Mann Whitney y Chi-Cuadrado. Results: Corroborated differences in tests, where the control group got better scores than the group of cases; however, it was not possible to find a correlation between empathy and theory of mind. Conclusion: It is suggested new researches with larger sample size to avoid the dispersion of data.
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BACKGROUND: Epstein-Barr virus (EBV) is a member of the Herpesviridae family and is associated with Hodgkin lymphoma (HL). Isolates of EBV are classified according to sequence variation in the latency genes such as Epstein-Barr virus nuclear antigen (EBNA). EBNA2 contains the most divergent locus and is classified into type 1 and type 2 or EBNA2A and EBNA2B, respectively. We compared the frequency of EBV and the distribution of EBNA genotypes in Mexican children and adults with HL. PATIENTS AND METHODS: Lymph node biopsy specimens from children and adults with HL were embedded in paraffin. EBV was identified by LMP1 amplification and Epstein-Barr-encoded RNA EBER by in situ hybridization (ISH) and genotyped as EBNA2A or EBNA2B using nested polymerase chain reaction (PCR) and specific primers for the detection of subtype. RESULTS: Sixty-six samples were obtained from 3 hospitals-42 (63%) from children and 24 (37%) from adults with HL. Thirty-two of the 42 samples (76.1%) were positive for EBV in children and 16 of 24 (66.6%) samples were positive in adults (P = .41). In both children and adults, EBV was found more frequently in male patients. Thirty-four of 48 cases could be typed (70.8%). EBNA2A was found in 7/21 (33.3%) children and in 4/13 (30.8%) adults (P = 1.0), and EBNA2B was found in 10/21 (47.6%) children and in 9/13 (69.2%) adults (P = .22). A mix of subtypes was found in 4/21 (19%) children. CONCLUSION: EBV was found frequently in both children and adults with HL. EBNA2B was the most frequent subtype, and a high frequency of mixed subtypes was found in children.
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Infecções por Vírus Epstein-Barr/virologia , Antígenos Nucleares do Vírus Epstein-Barr/genética , Herpesvirus Humano 4/isolamento & purificação , Doença de Hodgkin/virologia , Proteínas Virais/genética , Adolescente , Adulto , Criança , Pré-Escolar , Infecções por Vírus Epstein-Barr/patologia , Feminino , Genótipo , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/imunologia , Doença de Hodgkin/patologia , Humanos , Imuno-Histoquímica , Hibridização In Situ , Masculino , Estudos Retrospectivos , Adulto JovemRESUMO
The effect of preventive human papillomavirus (HPV) vaccination on the reduction of the cervical cancer (CC) burden will not be known for 30 years. Therefore, it's still necessary to improve the procedures for CC screening and treatment. The objective of this study was to identify and characterize cellular targets that could be considered potential markers for screening or therapeutic targets. A pyramidal strategy was used. Initially the expression of 8,638 genes was compared between 43 HPV16-positive CCs and 12 healthy cervical epitheliums using microarrays. A total of 997 genes were deregulated, and 21 genes that showed the greatest deregulation were validated using qRT-PCR. The 6 most upregulated genes (CCNB2, CDC20, PRC1, SYCP2, NUSAP1, CDKN3) belong to the mitosis pathway. They were further explored in 29 low-grade cervical intraepithelial neoplasias (CIN1) and 21 high-grade CIN (CIN2/3) to investigate whether they could differentiate CC and CIN2/3 (CIN2+) from CIN1 and controls. CCNB2, PRC1, and SYCP2 were mostly associated with CC and CDC20, NUSAP1, and CDKN3 were also associated with CIN2/3. The sensitivity and specificity of CDKN3 and NUSAP1 to detect CIN2+ was approximately 90%. The proteins encoded by all 6 genes were shown upregulated in CC by immunohistochemistry. The association of these markers with survival was investigated in 42 CC patients followed up for at least 42 months. Only CDKN3 was associated with poor survival and it was independent from clinical stage (HRâ=â5.9, 95%CIâ=â1.4-23.8, pâ=â0.01). CDKN3 and NUSAP1 may be potential targets for the development of screening methods. Nevertheless, further studies with larger samples are needed to define the optimal sensitivity and specificity. Inhibition of mitosis is a well-known strategy to combat cancers. Therefore, CDKN3 may be not only a screening and survival marker but a potential therapeutic target in CC. However, whether it's indispensable for tumor growth remains to be demonstrated.
Assuntos
Adenocarcinoma/mortalidade , Biomarcadores Tumorais/genética , Carcinoma de Células Escamosas/mortalidade , Mitose/genética , Infecções por Papillomavirus/mortalidade , Displasia do Colo do Útero/mortalidade , Neoplasias do Colo do Útero/mortalidade , Adenocarcinoma/diagnóstico , Adenocarcinoma/genética , Adulto , Idoso , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/genética , Colo do Útero/metabolismo , Detecção Precoce de Câncer , Feminino , Perfilação da Expressão Gênica , Humanos , Pessoa de Meia-Idade , Gradação de Tumores , Invasividade Neoplásica , Análise de Sequência com Séries de Oligonucleotídeos , Papillomaviridae/fisiologia , Infecções por Papillomavirus/diagnóstico , Infecções por Papillomavirus/genética , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sensibilidade e Especificidade , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/genética , Adulto Jovem , Displasia do Colo do Útero/diagnóstico , Displasia do Colo do Útero/genéticaRESUMO
To identify when during fetal development connexins (Cxs) 26 (Cx26) 32 (Cx32), and 36 (Cx36) begin to be expressed, as well as to characterize their spatial distribution, real time polymerase chain reaction and immunolabeling studies were performed. Total RNA from mouse pancreases at 13 and 18 days postcoitum (dpc) and 3 days postpartum (dpp) was analyzed. In addition, pancreatic sections of mouse at 13, 14, 15, 16, 18 dpc and 3 dpp and of rat at term were double labeled with either anti-insulin or anti-α-amylase and anti-Cx26 or -Cx32 or -Cx36 antibodies and studied with confocal microscopy. From day 13 dpc, Cxs 26, 32, and 36 transcripts were identified and their levels increased with age. At 13-14 dpc, Cxs 26 and 32 were localized in few acinar cells, whereas Cx36 was distributed in small beta cell clumps. From day 14 dpc onwards, the number of labeled cells and relative immunofluorescent reactivity of all three Cxs at junctional membranes of the respective cell types increased. Cxs 26 and 32 colocalized in fetal acinar cells. In rat pancreas at term, a similar connexin distribution was found. Relative Cxs levels evaluated by immunoblotting also increased (two-fold) in pancreas homogenates from day 18 dpc to 3 dpp. The early cell specific, wide distribution, and age dependent expression of Cxs 26, 32, and 36 during fetal pancreas ontogeny suggests their possible involvement in pancreas differentiation and prenatal maturation.
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Conexinas/metabolismo , Células Secretoras de Insulina/metabolismo , Pâncreas Exócrino/metabolismo , Pâncreas/embriologia , Pâncreas/crescimento & desenvolvimento , Animais , Animais Recém-Nascidos , Conexina 26 , Conexinas/genética , Feminino , Feto/embriologia , Feto/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Masculino , Camundongos , Camundongos Endogâmicos , Pâncreas/metabolismo , Gravidez , Reação em Cadeia da Polimerase em Tempo Real , Proteína beta-1 de Junções Comunicantes , Proteína delta-2 de Junções ComunicantesRESUMO
Asian-American (AA) variants of human papillomavirus 16 (HPV-16) are linked to a high incidence of cervical cancer in Mexico, with some evidence strongly suggesting that they are more oncogenic than European (E) variants, including their association with younger women and their higher associated risk of cervical cancer. Differences in the regulation of viral E6/E7 oncogene transcription by the E2 protein may be involved in the higher oncogenicity of AA variants. In E variants, E6/E7 oncogene transcription is repressed by the E2 protein and is frequently up-regulated by the destruction of the E2 gene during viral integration. In contrast, the E2 gene is retained in full in most AA-positive carcinomas, raising the possibility of alternative mechanisms for increasing viral oncogene transcription. The authors investigated whether the higher oncogenicity of AA variants is linked to differences in E6/E7 oncogene transcription and the mechanism of E2 deactivation. E6/E7 and E1/E2 transcripts were explored by RT-PCR in 53 HPV-16-positive cervical carcinomas, 39 retaining (20 European and 19 AA) and 14 having lost (12 European and 2 AA) the E1/E2 genes, and transcription repression activity of the AA E2 genes was tested in four cell lines that constitutively express the beta-galactosidase reporter or E6/E7 genes driven by the viral long control region. E6/E7 oncogene transcripts were found in all carcinomas, but only those positive for AA variants with E1/E2 genes had complete E2 transcripts. E2 transcripts were down-regulated by splicing in E-positive carcinomas retaining E1/E2. AA E2 genes were impaired for repression of E6/E7 oncogene transcription in vivo. These results suggest that E6/E7 oncogene expression starts earlier in AA than E variant infections, since E variants need E2 to be destroyed or down-regulated.
Assuntos
Proteínas de Ligação a DNA , Proteínas Oncogênicas Virais/genética , Proteínas Oncogênicas Virais/fisiologia , Papillomaviridae/patogenicidade , Proteínas Repressoras/fisiologia , Neoplasias do Colo do Útero/virologia , Feminino , Regulação Viral da Expressão Gênica , Humanos , Proteínas E7 de PapillomavirusRESUMO
Among the four parasite species causing malaria in humans, Plasmodium vivax prevails on both the Asian and the American continents. Several antigens from this parasite's erythrocytic stages have been characterised and some of them are considered to be good vaccine candidates. The P. vivax merozoite surface protein-1 (PvMSP-1) is a 200 kDa antigen, thought to mediate the initial contact between the merozoite and the erythrocyte. An effective blockage of this interaction could be important in anti-malarial vaccine design. This study analyses the genetic polymorphism, binding to both reticulocytes and erythrocytes, antigenicity and immunogenicity of two recombinant proteins belonging to the 33 kDa PvMSP-1 proteolytic fragment. Both regions showed very low genetic variation, bound reticulocytes with higher affinity than erythrocytes, were recognised by naturally P. vivax-infected patient sera and were immunogenic when used to immunise rabbits, making them good vaccine candidates against P. vivax, to be further preclinically tested in the Aotus monkey model.