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1.
J Med Primatol ; 53(3): e12713, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38802986

RESUMEN

A senile male black capuchin monkey (Sapajus nigritus) kept under human care in a Zoo was found dead after 2 weeks presenting signals of weight loss and hyporexia. Histopathological revealed a necrotizing encephalitis. Although it was not observed microscopically, Sarcocystis sp infection was detected in brain tissue from molecular assays. These infections have been rarely described in neotropical primates, particularly associated with tissue lesions.


Asunto(s)
Enfermedades de los Monos , Sarcocystis , Sarcocistosis , Animales , Sarcocistosis/veterinaria , Sarcocistosis/diagnóstico , Sarcocistosis/parasitología , Sarcocystis/aislamiento & purificación , Sarcocystis/genética , Enfermedades de los Monos/parasitología , Enfermedades de los Monos/diagnóstico , Masculino , Animales de Zoológico , Resultado Fatal , Encefalitis/veterinaria , Encefalitis/parasitología , Encefalitis/diagnóstico , Sapajus
2.
J Med Primatol ; 53(3): e12716, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38831476

RESUMEN

Neotropical primates rarely exhibit active tuberculosis. A brown howler monkey was found injured in an urban area. Histopathology revealed granulomatous inflammation in the lungs, lymph nodes, and liver. Immunohistochemistry and molecular analysis confirmed the presence of Mycobacterium tuberculosis complex. The findings highlight the importance of TB surveillance in nonhuman primates.


Asunto(s)
Alouatta , Enfermedades de los Monos , Mycobacterium tuberculosis , Tuberculosis , Animales , Enfermedades de los Monos/microbiología , Enfermedades de los Monos/patología , Brasil , Mycobacterium tuberculosis/aislamiento & purificación , Tuberculosis/veterinaria , Tuberculosis/microbiología , Tuberculosis/patología , Masculino , Femenino
3.
Cell Mol Life Sci ; 80(8): 234, 2023 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-37505242

RESUMEN

The human chemokine stromal cell-derived factor-1 (SDF-1) or CXCL12 is involved in several homeostatic processes and pathologies through interaction with its cognate G protein-coupled receptor CXCR4. Recent research has shown that CXCL12 is present in the lungs and circulation of patients with coronavirus disease 2019 (COVID-19). However, the question whether the detected CXCL12 is bioactive was not addressed. Indeed, the activity of CXCL12 is regulated by NH2- and COOH-terminal post-translational proteolysis, which significantly impairs its biological activity. The aim of the present study was to characterize proteolytic processing of CXCL12 in broncho-alveolar lavage (BAL) fluid and blood plasma samples from critically ill COVID-19 patients. Therefore, we optimized immunosorbent tandem mass spectrometry proteoform analysis (ISTAMPA) for detection of CXCL12 proteoforms. In patient samples, this approach uncovered that CXCL12 is rapidly processed by site-specific NH2- and COOH-terminal proteolysis and ultimately degraded. This proteolytic inactivation occurred more rapidly in COVID-19 plasma than in COVID-19 BAL fluids, whereas BAL fluid samples from stable lung transplantation patients and the non-affected lung of lung cancer patients (control groups) hardly induced any processing of CXCL12. In COVID-19 BAL fluids with high proteolytic activity, processing occurred exclusively NH2-terminally and was predominantly mediated by neutrophil elastase. In low proteolytic activity BAL fluid and plasma samples, NH2- and COOH-terminal proteolysis by CD26 and carboxypeptidases were observed. Finally, protease inhibitors already approved for clinical use such as sitagliptin and sivelestat prevented CXCL12 processing and may therefore be of pharmacological interest to prolong CXCL12 half-life and biological activity in vivo.


Asunto(s)
COVID-19 , Humanos , Proteolisis , Quimiocina CXCL12/metabolismo , Péptido Hidrolasas , Pulmón/metabolismo , Receptores CXCR4 , Procesamiento Proteico-Postraduccional
5.
Int J Mol Sci ; 24(5)2023 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-36902230

RESUMEN

Mayaro virus (MAYV) is an emerging arthropod-borne virus endemic in Latin America and the causative agent of arthritogenic febrile disease. Mayaro fever is poorly understood; thus, we established an in vivo model of infection in susceptible type-I interferon receptor-deficient mice (IFNAR-/-) to characterize the disease. MAYV inoculations in the hind paws of IFNAR-/- mice result in visible paw inflammation, evolve into a disseminated infection and involve the activation of immune responses and inflammation. The histological analysis of inflamed paws indicated edema at the dermis and between muscle fibers and ligaments. Paw edema affected multiple tissues and was associated with MAYV replication, the local production of CXCL1 and the recruitment of granulocytes and mononuclear leukocytes to muscle. We developed a semi-automated X-ray microtomography method to visualize both soft tissue and bone, allowing for the quantification of MAYV-induced paw edema in 3D with a voxel size of 69 µm3. The results confirmed early edema onset and spreading through multiple tissues in inoculated paws. In conclusion, we detailed features of MAYV-induced systemic disease and the manifestation of paw edema in a mouse model extensively used to study infection with alphaviruses. The participation of lymphocytes and neutrophils and expression of CXCL1 are key features in both systemic and local manifestations of MAYV disease.


Asunto(s)
Infecciones por Alphavirus , Alphavirus , Animales , Ratones , Infecciones por Alphavirus/patología , Inflamación , Sincrotrones , Microtomografía por Rayos X
6.
Scand J Gastroenterol ; 56(8): 920-928, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34218733

RESUMEN

AIMS: Epigenetic alterations of genes involved in colorectal carcinogenesis are likely to be informative biomarkers for early detection. We assessed the methylation profile of a panel of seven colon cancer-related genes comparing normal colon, colorectal cancer (CRC) precursor lesions and cancer tissues from a Brazilian cohort. METHODS: The cohort comprised 114 CRC patients, including 40 matched normal tissue, 47 patients with adenomas, 33 with serrated polyps and 8 with normal colonic biopsy. DNA methylation status of SEPT9, ALX4, NDRG4, BMP3, APC, p16 and MLH1 was determined by pyrosequencing and correlated with clinicopathological features. Sensitivity, specificity, positive predictive value and negative predictive value were calculated for all genes using cancer endpoint. RESULTS: The most frequently methylated genes in cancer and in precancer lesions were SEPT9, ALX4, NDRG4, and BMP3, ranging from 55.3 to 95% of the samples. Overall, the frequency of methylation of these four genes in normal colonic tissue was significantly lower as compared to cancer or precursor lesions both in adenoma-carcinoma (p < .001 and p < .050) and serrated (sessile-serrated lesion) (p < .001 and p < .050) pathways. Additionally, sensitivity for the cancer endpoint ranged from 65.6 to 91.8%, and specificity from 17.9 to 62.9% for SEPT9, ALX4, NDRG4, and BMP3 genes. Moreover, the comethylation of ≥4 genes was higher in sessile-serrated lesion (87.5%) and conventional adenomas (78.7%) than in hyperplastic polyps (43.7%) (p = .025) and was significantly associated with proximal cancers (p = .042). CONCLUSIONS: Our study suggests the DNA methylation can constitute potential biomarkers in CRC screening of Brazilian population.


Asunto(s)
Adenoma , Neoplasias del Colon , Pólipos del Colon , Neoplasias Colorrectales , Adenoma/genética , Biomarcadores de Tumor/genética , Neoplasias del Colon/genética , Pólipos del Colon/genética , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/genética , Metilación de ADN , Detección Precoz del Cáncer , Humanos
7.
Pathobiology ; 88(2): 127-140, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33291114

RESUMEN

Colorectal cancer (CRC) is one of the most frequent and deadly neoplasms worldwide. Genetic factors, lifestyle habits, and inflammation are important risk factors associated with CRC development. In recent years, growing evidence has supporting the significant role of the intestinal microbiome in CRC carcinogenesis. Disturbances in the healthy microbial balance, known as dysbiosis, are frequently observed in these patients. Pathogenic microorganisms that induce intestinal dysbiosis have become an important target to determine the role of bacterial infection in tumorigenesis. Interestingly, the presence of different bacterial strains, such as Fusobacterium nucleatum, has been detected in tissue and stool from patients with CRC and associated with substantial clinical and molecular features, as well as with patient therapy response. Therefore, understanding how the presence and levels of F. nucleatumstrains in the gut affect the risk of CRC onset and progression may inform suitable candidates for interventions focused on modulation of this bacteria. Here we review new insights into the role of gut microbiota in CRC carcinogenesis and the clinical utility of using the detection of F. nucleatum in different settings such as screening, prognosis, and microbiota modulation as a means to prevent cancer, augment therapies, and reduce adverse effects of treatment.


Asunto(s)
Carcinogénesis , Neoplasias Colorrectales/microbiología , Fusobacterium nucleatum/patogenicidad , Intestinos/patología , Animales , Transformación Celular Neoplásica , Progresión de la Enfermedad , Disbiosis , Microbioma Gastrointestinal , Humanos , Intestinos/microbiología , Ratones , Factores de Riesgo
8.
Eur Arch Otorhinolaryngol ; 278(5): 1411-1418, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-32989493

RESUMEN

PURPOSE: This study aimed to evaluate the pre- and post-operative quality-of-life of patients submitted to the resection of pituitary adenoma via endoscopic transsphenoidal. METHODS: This was a prospective study on patients submitted to endoscopic transsphenoidal pituitary surgery with the harvest of a nasoseptal flap who responded to the questionnaires FV-36 and SNOT-22 in the pre-operative and in months 1, 3 and 6 following the surgical procedure. RESULTS: A total of 42 patients submitted to pituitary adenoma resection surgery via endoscopic transsphenoidal with a nasoseptal flap were recruited. In all of the physical and mental domains (SF-36) evaluated, there was an improvement in the long-term evaluation (6 months), compared to the pre-operative, as well as in the site-specific evaluation (SNOT-22). CONCLUSION: The global and site-specific questionnaires in the 6th post-operative month follow-up presented an important improvement in all the physical and mental domains evaluated, as well as in nasal function in the perception of the patients submitted to pituitary adenoma resection via endoscopic transsphenoidal, demonstrating the safety and efficiency of the procedure.


Asunto(s)
Neoplasias Hipofisarias , Endoscopía , Humanos , Neoplasias Hipofisarias/cirugía , Estudios Prospectivos , Calidad de Vida , Resultado del Tratamiento
9.
Appl Environ Microbiol ; 84(23)2018 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-30266724

RESUMEN

The high-altitude atmosphere is a harsh environment with extremely low temperatures, low pressure, and high UV irradiation. For this reason, it has been proposed as an analogue for Mars, presenting deleterious factors similar to those on the surface of that planet. We evaluated the survival of extremophilic UV-resistant yeasts isolated from a high-elevation area in the Atacama Desert under stratospheric conditions. As biological controls, intrinsically resistant Bacillus subtilis spores were used. Experiments were performed in two independent stratospheric balloon flights and with an environmental simulation chamber. The three following different conditions were evaluated: (i) desiccation, (ii) desiccation plus exposure to stratospheric low pressure and temperature, and (3) desiccation plus exposure to the full stratospheric environment (UV, low pressure, and temperature). Two strains, Naganishia (Cryptococcus) friedmannii 16LV2 and Exophiala sp. strain 15LV1, survived full exposures to the stratosphere in larger numbers than did B. subtilis spores. Holtermanniella watticus (also known as Holtermanniella wattica) 16LV1, however, suffered a substantial loss in viability upon desiccation and did not survive the stratospheric UV exposure. The remarkable resilience of N. friedmannii and Exophiala sp. 15LV1 under the extreme Mars-like conditions of the stratosphere confirms its potential as a eukaryotic model for astrobiology. Additionally, our results with N. friedmannii strengthen the recent hypothesis that yeasts belonging to the Naganishia genus are fit for aerial dispersion, which might account for the observed abundance of this species in high-elevation soils.IMPORTANCE Studies of eukaryotic microorganisms under conditions of astrobiological relevance, as well as the aerial dispersion potential of extremophilic yeasts, are still lacking in the literature compared to works with bacteria. Using stratospheric balloon flights and a simulation chamber, we demonstrate that yeasts isolated from an extreme environment are capable of surviving all stressors found in the stratosphere, including intense UV irradiation, scoring an even higher survival than B. subtilis spores. Notably, the yeast N. friedmannii, which displayed one of the highest tolerances to the stratospheric environment in the experiments, was recently proposed to be adapted to airborne transportation, although such a hypothesis had not yet been tested. Our results strengthen such an assumption and can help explain the observed distribution and ecology of this particular yeast species.


Asunto(s)
Extremófilos/crecimiento & desarrollo , Levaduras/crecimiento & desarrollo , Atmósfera , Bacillus subtilis/crecimiento & desarrollo , Bacillus subtilis/efectos de la radiación , Frío , Desecación , Ambientes Extremos , Extremófilos/metabolismo , Extremófilos/efectos de la radiación , Marte , Viabilidad Microbiana , Rayos Ultravioleta , Agua/análisis , Agua/metabolismo , Levaduras/metabolismo , Levaduras/efectos de la radiación
10.
BMC Cancer ; 18(1): 193, 2018 02 17.
Artículo en Inglés | MEDLINE | ID: mdl-29454310

RESUMEN

BACKGROUND: Aberrant methylation is a frequent event in oral cancer. METHODS: In order to better characterize these alterations, a search for genes downregulated by aberrant methylation in oral squamous cell carcinoma (OSCC) was conducted through the mining of ORESTES dataset. Findings were further validated in OSCC cell lines and patients' samples and confirmed using TCGA data. Differentially expressed genes were identified in ORESTES libraries and validated in vitro using RT-PCR in HNSCC cell-lines and OSCC tumor samples. Further confirmation of these results was performed using mRNA expression and methylation data from The Cancer Genome Atlas (TCGA) data. RESULTS: From the set of genes selected for validation, CA3 and FHL1 were downregulated in 60% (12/20) and 75% (15/20) of OSCC samples, respectively, and in HNSCC cell lines. The treatment of cell lines JHU-13 and FaDu with the demethylating agent 5'-aza-dC was efficient in restoring CA3 and FHL1 expression. TCGA expression and methylation data on OSCC confirms the downregulation of these genes in OSCC samples and also suggests that expression of CA3 and FHL1 is probably regulated by methylation. The downregulation of CA3 and FHL1 observed in silico was validated in HNSCC cell lines and OSCC samples, showing the feasibility of integrating different datasets to select differentially expressed genes in silico. CONCLUSIONS: These results showed that the downregulation of CA3 and FHL1 data observed in the ORESTES libraries was validated in HNSCC cell lines and OSCC samples and in a large cohort of samples from the TCGA database. Moreover, it suggests that expression of CA3 and FHL1 could probably be regulated by methylation having an important role the oral carcinogenesis.


Asunto(s)
Biomarcadores de Tumor , Biología Computacional , Regulación Neoplásica de la Expresión Génica , Péptidos y Proteínas de Señalización Intracelular/genética , Proteínas con Dominio LIM/genética , Neoplasias de la Boca/genética , Proteínas Musculares/genética , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patología , Línea Celular Tumoral , Biología Computacional/métodos , Metilación de ADN , Regulación hacia Abajo , Epigénesis Genética , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Neoplasias de Cabeza y Cuello/genética , Neoplasias de Cabeza y Cuello/patología , Humanos , Neoplasias de la Boca/patología , Reproducibilidad de los Resultados , Carcinoma de Células Escamosas de Cabeza y Cuello , Transcriptoma
11.
Gynecol Oncol ; 150(3): 545-551, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29960712

RESUMEN

OBJECTIVES: The methylation profile of genes in precursor lesions in cervical cancer was characterized to improve screening techniques for high-grade intraepithelial neoplasia. METHODS: A total of 447 cervical cytology samples obtained from women who underwent colposcopy were examined. The cases were distributed as follows: (1) cervices without cervical intraepithelial neoplasia (CIN; n = 152); (2) cervices with a CIN grade of 1 (CIN 1; n = 147); and (3) cervices with a CIN grade of 2 or 3 (CIN 2/3; n = 148). The methylation pattern for a panel of 15 genes was analysed by quantitative methylation-specific PCR (qMSP) and compared between the groups (≤CIN 1 vs. CIN 2+). RESULTS: In the validation set, seven genes presented significantly different methylation profiles according to diagnosis, namely, DAPK1 (p = 0.001), EPB41L3 (p = 0.001), HIC1 (p = 0.028), hsa-miR-124-2 (p = 0.001), LMX1A (p = 0.001), SOX1 (p = 0.001), and TERT (p = 0.001). Six genes showed a significant increase in the frequency of methylation in the presence of hr-HPV, namely, DAPK1 (p = 0.001), EPB41L3 (p = 0.001), hsa-miR-124-2 (p = 0.001), LMX1A (p = 0.001), SOX1 (p = 0.001), and TERT (p = 0.001). The methylation of the hsa-miR-124 gene showed sensitivity and specificity (86.7% and 61.3%, respectively) similar to that of the HPV test (91.3% and 50.0%, respectively). The independent factors associated with the diagnosis of CIN 2+ and the methylation of the hsa-miR-124-2 (OR = 5.1), SOX1 (OR = 2.8), TERT (OR = 2.2), and LMX1A (OR = 2.0) genes were a positive test for hr-HPV (odds ratio [OR] = 5.5). CONCLUSIONS: Hypermethylation of the hsa-miR-124-2, SOX1, TERT, and LMX1A genes may be a promising biomarker for precursor lesions in cervical cancer regardless of the hr-HPV status.


Asunto(s)
Metilación de ADN , Displasia del Cuello del Útero/diagnóstico , Displasia del Cuello del Útero/genética , Neoplasias del Cuello Uterino/diagnóstico , Neoplasias del Cuello Uterino/genética , Adulto , Biomarcadores de Tumor/genética , Detección Precoz del Cáncer , Femenino , Humanos , Proteínas con Homeodominio LIM/genética , MicroARNs/genética , Persona de Mediana Edad , Papillomaviridae , Infecciones por Papillomavirus/complicaciones , Regiones Promotoras Genéticas , Factores de Transcripción SOXB1/genética , Sensibilidad y Especificidad , Telomerasa/genética , Factores de Transcripción/genética , Neoplasias del Cuello Uterino/patología , Neoplasias del Cuello Uterino/virología , Displasia del Cuello del Útero/patología , Displasia del Cuello del Útero/virología
12.
BMC Med ; 13: 108, 2015 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-25956054

RESUMEN

BACKGROUND: The presence of metastatic disease in cervical lymph nodes of head and neck squamous cell carcinoma (HNSCC) patients is a very important determinant in therapy choice and prognosis, with great impact in overall survival. Frequently, routine lymph node staging cannot detect occult metastases and the post-surgical histologic evaluation of resected lymph nodes is not sensitive in detecting small metastatic deposits. Molecular markers based on tissue-specific microRNA expression are alternative accurate diagnostic markers. Herein, we evaluated the feasibility of using the expression of microRNAs to detect metastatic cells in formalin-fixed paraffin-embedded (FFPE) lymph nodes and in fine-needle aspiration (FNA) biopsies of HNSCC patients. METHODS: An initial screening compared the expression of 667 microRNAs in a discovery set comprised by metastatic and non-metastatic lymph nodes from HNSCC patients. The most differentially expressed microRNAs were validated by qRT-PCR in two independent cohorts: i) 48 FFPE lymph node samples, and ii) 113 FNA lymph node biopsies. The accuracy of the markers in identifying metastatic samples was assessed through the analysis of sensitivity, specificity, accuracy, negative predictive value, positive predictive value, and area under the curve values. RESULTS: Seven microRNAs highly expressed in metastatic lymph nodes from the discovery set were validated in FFPE lymph node samples. MiR-203 and miR-205 identified all metastatic samples, regardless of the size of the metastatic deposit. Additionally, these markers also showed high accuracy when FNA samples were examined. CONCLUSIONS: The high accuracy of miR-203 and miR-205 warrant these microRNAs as diagnostic markers of neck metastases in HNSCC. These can be evaluated in entire lymph nodes and in FNA biopsies collected at different time-points such as pre-treatment samples, intraoperative sentinel node biopsy, and during patient follow-up. These markers can be useful in a clinical setting in the management of HNSCC patients from initial disease staging and therapy planning to patient surveillance.


Asunto(s)
Biomarcadores de Tumor/análisis , Carcinoma de Células Escamosas/patología , Neoplasias de Cabeza y Cuello/patología , Metástasis Linfática/diagnóstico , MicroARNs , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/genética , Carcinoma de Células Escamosas/genética , Femenino , Neoplasias de Cabeza y Cuello/genética , Humanos , Ganglios Linfáticos/patología , Metástasis Linfática/genética , Masculino , Persona de Mediana Edad , Pronóstico , Sensibilidad y Especificidad , Carcinoma de Células Escamosas de Cabeza y Cuello
13.
J Transl Med ; 13: 262, 2015 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-26264462

RESUMEN

PURPOSE: Definitive radiation therapy is the mainstay of treatment for early stage laryngeal squamous cell carcinoma (LSCC). However, up to 30% of the patients do not respond to radiotherapy. Unfortunately, we are unable to predict which tumors are likely to respond to radiation, and which will be resistant and persist. Therefore, the development of novel markers to predict response to radiotherapy is urgently needed. This study was designed to evaluate the expression pattern of microRNAs (miRNAs) in LSCC in order to identify markers capable of segregating radioresistant and radiosensitive tumors and to investigate the relationship between the expression of these miRNAs and the prognosis of LSCC. METHODS: The expression profile of 667 miRNAs was determined in an initial screening of nine early-stage LSCC samples (5 radioresistant and 4 radiosensitive) using TaqMan Low-Density Array (TLDA). Real-time polymerase chain reactions were performed to validate the expression of selected miRNAs in an expanded LSCC cohort (20 radioresistant and 14 radiosensitive). The miRNA expression level was scored as high or low based on the median of the expression in the LSCC samples. RESULTS: A comprehensive miRNA expression profiling enabled the identification of four miRNAs (miR-296-5p miR-452, miR-183* and miR-200c) differentially expressed in radioresistant LSCC. Moreover, the analysis of additional 34 LSCC samples, confirmed the expression of miR-296-5p as significantly related to radioresistance (p = 0.002) as well as an association of this marker with recurrence (p = 0.025) in early stage laryngeal cancer. CONCLUSIONS: This study indicates that miR-296-5p expression is associated with resistance to radiotherapy and tumor recurrence in early stage LSCC, showing the feasibility of this marker as a novel prognostic factor for this malignance. Furthermore, miR-296-5p expression could be helpful in the identification of tumors resistant to radiotherapy; thus aiding the clinicians in the choice of the best therapeutic scheme to be used in each case.


Asunto(s)
Biomarcadores de Tumor/genética , Regulación Neoplásica de la Expresión Génica , Neoplasias Laríngeas/genética , Neoplasias Laríngeas/radioterapia , MicroARNs/genética , Tolerancia a Radiación/genética , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Perfilación de la Expresión Génica , Humanos , Neoplasias Laríngeas/patología , Masculino , MicroARNs/metabolismo , Persona de Mediana Edad , Estadificación de Neoplasias , Neoplasias de Células Escamosas/genética , Neoplasias de Células Escamosas/patología , Neoplasias de Células Escamosas/radioterapia , Pronóstico , Análisis de Supervivencia
14.
Biochem J ; 464(3): 323-34, 2014 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-25253091

RESUMEN

Glycogen functions as a carbohydrate reserve in a variety of organisms and its metabolism is highly regulated. The activities of glycogen synthase and glycogen phosphorylase, the rate-limiting enzymes of the synthesis and degradation processes, respectively, are regulated by allosteric modulation and reversible phosphorylation. To identify the protein kinases affecting glycogen metabolism in Neurospora crassa, we performed a screen of 84 serine/threonine kinase knockout strains. We identified multiple kinases that have already been described as controlling glycogen metabolism in different organisms, such as NcSNF1, NcPHO85, NcGSK3, NcPKA, PSK2 homologue and NcATG1. In addition, many hypothetical kinases have been implicated in the control of glycogen metabolism. Two kinases, NcIME-2 and NcNIMA, already functionally characterized but with no functions related to glycogen metabolism regulation, were also identified. Among the kinases identified, it is important to mention the role of NcSNF1. We showed in the present study that this kinase was implicated in glycogen synthase phosphorylation, as demonstrated by the higher levels of glycogen accumulated during growth, along with a higher glycogen synthase (GSN) ±glucose 6-phosphate activity ratio and a lesser set of phosphorylated GSN isoforms in strain Ncsnf1KO, when compared with the wild-type strain. The results led us to conclude that, in N. crassa, this kinase promotes phosphorylation of glycogen synthase either directly or indirectly, which is the opposite of what is described for Saccharomyces cerevisiae. The kinases also play a role in gene expression regulation, in that gdn, the gene encoding the debranching enzyme, was down-regulated by the proteins identified in the screen. Some kinases affected growth and development, suggesting a connection linking glycogen metabolism with cell growth and development.


Asunto(s)
Glucógeno Sintasa/metabolismo , Neurospora crassa/enzimología , Proteínas Serina-Treonina Quinasas/metabolismo , Regulación Enzimológica de la Expresión Génica , Glucógeno/biosíntesis , Ensayos Analíticos de Alto Rendimiento , Neurospora crassa/química , Neurospora crassa/genética , Organismos Modificados Genéticamente , Fosforilación , Proteínas Quinasas/aislamiento & purificación , Proteínas Quinasas/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/aislamiento & purificación , Trehalosa/metabolismo
15.
Cancer Immunol Immunother ; 63(11): 1189-97, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25099367

RESUMEN

INTRODUCTION: Multiple myeloma (MM) development involves a series of genetic abnormalities and changes in the bone marrow (BM) microenvironment, favoring the growth of the tumor and failure of local immune control. T regulatory (Treg) cells play an important role in dampening anti-tumor immune responses while T-helper-17 (Th17) cells seem to be critical for the eradication of malignant cells. The aim of our study was to characterize the expression of Treg- and Th17-related genes in total myeloma BM samples to assess their role as biomarkers, prognostic factors, and possible therapeutic targets in this incurable disease. METHODS: Expression of markers for Treg (FOXP3, CTLA4) and Th17 cells (RORγt) was determined by quantitative real-time PCR in BM aspirates of 46 MM patients, four patients with monoclonal gammopathy of undetermined significance, five solitary plasmacytomas, and five healthy BM donors. Gene expression was evaluated regarding an influence on the patients' overall survival (OS). RESULTS: FOXP3 and CTLA4 presented a sixfold (p = 0.02) and 30-fold higher expression (p = 0.03), respectively, in MM patients than in controls. RORγt expression was similar in MM patients and controls. Median OS of MM patients was 16.8 (range 4.5-29.1) months, and international staging system was the only independent prognostic factor for patients survival. CONCLUSIONS: Overexpression of FOXP3 and CTLA4 in total BM samples suggests a local accumulation of immunosuppressive Tregs, the MM tumor environment, possibly dampening anti-tumor host immune responses. Therapeutic approaches targeting Treg cells and restoring local anti-tumor immunity may provide new treatment strategies for this incurable malignancy.


Asunto(s)
Médula Ósea/metabolismo , Antígeno CTLA-4/metabolismo , Factores de Transcripción Forkhead/metabolismo , Mieloma Múltiple/metabolismo , Linfocitos T Reguladores/citología , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores , Células de la Médula Ósea/citología , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Terapia de Inmunosupresión , Masculino , Persona de Mediana Edad , Gammopatía Monoclonal de Relevancia Indeterminada/genética , Mieloma Múltiple/mortalidad , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/metabolismo , Plasmacitoma/genética , Plasmacitoma/metabolismo , Sindecano-1/metabolismo , Células Th17/citología , Resultado del Tratamiento
16.
Gynecol Obstet Invest ; 78(1): 12-5, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24852939

RESUMEN

BACKGROUND: This study aimed to evaluate the effect of long-term high-dose tibolone on the bladders and urethras of ovariectomized rats. METHODS: Bilateral ovariectomy was performed in 14 young adult rats randomly divided into 2 groups. Experimental rats (n = 9) received 1 mg/day of tibolone orally; control rats (n = 6) received a placebo. After 150 days, the bladders and urethras were removed. Bladder cell proliferation was analyzed by Ki-67 immunohistochemistry. A histomorphometric analysis was performed for epithelial thickness and the percent areas of collagen fibers and blood vessels. Data were compared using a Mann-Whitney test (significance level at p < 0.05). RESULTS: Urothelial thickness and the percent area of collagen fibers and blood vessels were not significantly different between the tibolone and control groups in the bladder and urethra. In addition, urothelium cell proliferation in the bladder showed a low immunopositivity in both groups. Furthermore, the glycogen and glycoprotein contents in urethral epithelium were slightly modified by tibolone and no change was observed in the bladder. CONCLUSION: Long-term administration of tibolone has no effect on urothelial trophism, collagen fibers, the number of vessels, or cell proliferation in the urethra and bladder of the ovariectomized rat.


Asunto(s)
Moduladores de los Receptores de Estrógeno/administración & dosificación , Norpregnenos/administración & dosificación , Ovariectomía , Uretra/efectos de los fármacos , Vejiga Urinaria/efectos de los fármacos , Animales , Femenino , Glucógeno/análisis , Glicoproteínas/análisis , Ratas , Ratas Wistar , Uretra/anatomía & histología , Vejiga Urinaria/anatomía & histología , Urotelio/anatomía & histología , Urotelio/química , Urotelio/efectos de los fármacos
17.
Astrobiology ; 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38853686

RESUMEN

The district of Perus, located in the city of São Paulo, Brazil, is renowned for its weathered granitic-pegmatitic masses, which harbor a significant number of uraniferous minerals that contribute to ionizing radiation levels up to 20 times higher than the background levels. In this study, aseptically collected mineral samples from the area were utilized to isolate 15 microorganisms, which were subjected to pre-screening tests involving UV-C and UV-B radiation. The microorganisms that exhibited the highest resistance to ultraviolet (UV) radiation were selected for the construction of survival curves for UV-C, broad-band UV-B, and solar simulation resistance testing. Subsequently, the four strains that demonstrated superior survival capabilities under UV radiation exposure were chosen for 16S rRNA gene sequencing. Among these, Nocardioides sp. O4R and Nocardioides sp. MA2R demonstrated the most promising outcomes in the UV radiation resistance assessments, showcasing comparable performance to the well-established radioresistant model organism Deinococcus radiodurans. These findings underscore the potential of naturally occurring high-radiation environments as valuable resources for the investigation of UV-resistant microorganisms.

18.
Head Neck ; 46(3): 461-472, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38095042

RESUMEN

BACKGROUND: Epidermal growth factor receptor (EGFR) is frequently activated in head and neck squamous cell carcinoma (HNSCC) and serves as a valuable target for therapy. Despite the availability of the EGFR inhibitors Cetuximab, Afatinib, and Allitinib, there are limited predictive markers for their response. Understanding molecular aberrations in HNSCC could facilitate the identification of new strategies for patient clinical and biological classification, offering novel therapeutic avenues. METHODS: We assessed CCNA1, DCC, MGMT, CDKN2A/p16, and DAPK methylation status in HNSCC cell lines and their association with anti-EGFR treatment response. RESULTS: MGMT methylation status displayed high sensitivity and specificity in distinguishing sensitive and resistant HNSCC cell lines to Afatinib (AUC = 0.955) and Allitinib (AUC = 0.935). Moreover, DAPK methylation status predicted response to Allitinib with high accuracy (AUC = 0.852), indicating their putative predictive biomarker roles. CONCLUSION: These findings hold promise for the development of more personalized and effective treatment approaches for HNSCC patients.


Asunto(s)
Acrilamidas , Carcinoma de Células Escamosas , Neoplasias de Cabeza y Cuello , Quinazolinas , Humanos , Carcinoma de Células Escamosas de Cabeza y Cuello/tratamiento farmacológico , Carcinoma de Células Escamosas de Cabeza y Cuello/genética , Carcinoma de Células Escamosas/tratamiento farmacológico , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Afatinib , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Neoplasias de Cabeza y Cuello/genética , Cetuximab/farmacología , Cetuximab/uso terapéutico , Receptores ErbB/metabolismo , Línea Celular Tumoral , Metilasas de Modificación del ADN/genética , Metilasas de Modificación del ADN/uso terapéutico , Proteínas Supresoras de Tumor , Enzimas Reparadoras del ADN/genética , Enzimas Reparadoras del ADN/uso terapéutico
19.
Int J Food Microbiol ; 420: 110783, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-38851046

RESUMEN

Despite the wide variety of native and exotic fruits in Brazil, there is limited understanding of their ability to support pathogens during storage. This study aimed to evaluate the behavior of Salmonella enterica and Listeria monocytogenes inoculated into the pulp of eight fruits native and exotic to Brazil: Jenipapo (Genipa americana L.), Umbu (Spondias tuberosa Arruda), Maná (Solanum sessiliflorum), Cajá-manga (Spondias dulcis), Physalis (Physalis angulata L.), Feijoa (Acca sellowiana), Cupuaçu (Theobroma grandiflorum) (average pH < 3.3) and in a low acidy fruit: Abiu (Pouteria caimito) (pH 6.11). The pathogens were inoculated into the different fruits and stored at 10, 20, 30 and 37 °C for up to 12 h and 6 days, respectively. Among the fruits evaluated, Abiu was the only one that allowed Salmonella growth, showing higher δ-values at 20 and 30 °C (5.6 log CFU/g for both temperatures). For Physalis and Feijoa, there was a small reduction in the pathogen concentration (<1 log-cycle), mainly at 10 and 20 °C, indicating its ability to remain in the matrices. For the other fruits, notable negative δ-values were obtained, indicating a tendency towards microbial inactivation. The survival potential was significantly affected by temperature in Abiu, Maná, Cupuaçu, and Cajá-manga (p < 0.05). The same phenomena regarding δ-value were observed for L. monocytogenes population, with the greatest survival potential observed at 20 °C in Abiu (3.3 log CFU/g). Regarding the exponential growth rates in Abiu, the highest values were observed at 30 and 37 °C, both for Salmonella (4.6 and 4.9 log (CFU/g)/day, respectively) and for L. monocytogenes (2.8 and 2.7 log (CFU/g)/day, respectively), with no significant difference between both temperatures. Regarding microbial inactivation, L. monocytogenes showed greater resistance than Salmonella in practically all matrices. Jenipapo and Umbu were the pulps that, in general, had the greatest effect on reducing the population of pathogens. Furthermore, the increase in storage temperature seems to favor the increase on inactivation rates. In conclusion, Salmonella and L. monocytogenes can grow only in Abiu pulp, although they can survive in some acidic tropical fruits kept at refrigeration and abusive temperatures.


Asunto(s)
Microbiología de Alimentos , Frutas , Listeria monocytogenes , Salmonella enterica , Salmonella enterica/crecimiento & desarrollo , Listeria monocytogenes/crecimiento & desarrollo , Frutas/microbiología , Brasil , Temperatura , Recuento de Colonia Microbiana , Contaminación de Alimentos/análisis , Almacenamiento de Alimentos
20.
Artículo en Inglés | MEDLINE | ID: mdl-38953141

RESUMEN

Fecal immunochemical test (FIT) followed by colonoscopy in positive cases is commonly used for population-based colorectal cancer (CRC) screening. However, specificity of FIT for CRC is not ideal, and has poor performance for advanced adenoma detection. Fecal Fusobacterium nucleatum (Fn) detection has been proposed as a potential non-invasive biomarker for CRC and advanced adenoma detection. We aimed to evaluate the diagnostic performance of Fn detection using droplet digital PCR (ddPCR) in FIT samples from individuals enrolled in a CRC screening program with colorectal adenoma or cancer. We evaluated Fn presence in DNA isolated from FIT leftover material of 300 participants in a CRC Screening Program using ddPCR. The Fn DNA amount was classified as Fn-low/negative and Fn-high, and the association with patients clinicopathological features and accuracy measurements was calculated. Fn high levels were more prevalent in FIT-positive (47.2%n=34 of72) than FIT-negative samples (28.9%, n=66 of 228) (p<0.04). Among FIT-positive samples, high Fn levels were significantly more frequent in cancer patients (CA, n=8) when compared to normal (NT, n=16) (p=0.02), non-advanced adenomas (NAA, n=36) (p=0.01), and advanced adenomas (AA, n=12) (p=0.01). Performance analysis of Fn in FIT-positive samples for colorectal cancer detection yielded an AUC of 0.8203 (CI: 0.6464-0.9942), with high sensitivity (100%) and specificity of 50%%. Concluding, we showed the feasibility of detecting Fn in FIT leftovers using the ultrasensitive ddPCR technique. Furthermore, we highlighted the potential use of Fn levels in fecal samples to ameliorate CRC detection.

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