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1.
Anal Biochem ; : 115570, 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38763320

RESUMEN

Zinc plays a crucial role both in the immune system and endocrine processes. . Zinc restriction in the diet has been shown to lead to degeneration of the endocrine pancreas, resulting in hormonal imbalance within the ß-cells. Proteostasismay vary depending on the stage of a pathophysiological process, which underscores the need for tools aimed at directly analyzing biological status. Among proteomics methods, MALDI-ToF-MS can serve as a rapid peptidomics tool for analyzing extracts or by histological imaging. Here we report the optimization of MALDI imaging mass spectrometry analysis of histological thin sections from mouse pancreas. This optimization enables the identification of the major islet peptide hormones as well as the major accumulated precursors and/or proteolytic products of peptide hormones. Cross-validation of the identified peptide hormones was performed by LC-ESI-MS from pancreatic islet extracts. Mice subjected to a zinc-restricted diet exhibited a relatively lower amount of peptide intermediates compared to the control group. These findings provide evidence for a complex modulation of proteostasis by micronutrients imbalance, a phenomenon directly accessed by MALDI-MSI.

2.
Int J Sports Med ; 2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38684187

RESUMEN

We compared the effects of different calf training weekly sets on muscle size changes. Sixty-one untrained young women performed a calf training program for 6 weeks, 3 d·wk-1, with differences in the resistance training volume. The participants were randomly assigned to 1 of the 3 groups: 6-SET, 9-SET, and 12-SET calf training weekly sets. The calf raise exercise was performed in sets of 15-20 repetitions maximum. The muscle thickness measurements of medial gastrocnemius (MG), lateral gastrocnemius (LG), and soleus (SOL) were taken via B-mode ultrasound. We used the sum of the three-muscle thickness as a proxy for the triceps surae (TSSUM). The 12-SET group elicited greater increases than 6-SET in LG (6-SET = +8.1% vs. 12-SET = +14.3%; P = 0.017), SOL (6-SET = +6.7% vs. 12-SET = +12.7%; P = 0.024), and TSSUM (6-SET = +6.9% vs. 12-SET = +12.0%; P = 0.005), but there was no significant difference in MG changes (6-SET = +6.6% vs. 12-SET = +9.9%; P = 0.067). There were no significant differences when comparing 9-SET vs. 6-SET and 12-SET (P ≥ 0.099). Although all groups experienced calf muscle hypertrophy, our results suggest that the higher dose range may optimize triceps surae muscle size gains.

3.
Int J Mol Sci ; 25(7)2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38612533

RESUMEN

Colorectal cancer (CRC) screening relies primarily on stool analysis to identify occult blood. However, its sensitivity for detecting precancerous lesions is limited, requiring the development of new tools to improve CRC screening. Carcinogenesis involves significant alterations in mucosal epithelium glycocalyx that decisively contribute to disease progression. Building on this knowledge, we examined patient series comprehending premalignant lesions, colorectal tumors, and healthy controls for the T-antigen-a short-chain O-glycosylation of proteins considered a surrogate marker of malignancy in multiple solid cancers. We found the T-antigen in the secretions of dysplastic lesions as well as in cancer. In CRC, T-antigen expression was associated with the presence of distant metastases. In parallel, we analyzed a broad number of stools from individuals who underwent colonoscopy, which showed high T expressions in high-grade dysplasia and carcinomas. Employing mass spectrometry-based lectin-affinity enrichment, we identified a total of 262 proteins, 67% of which potentially exhibited altered glycosylation patterns associated with cancer and advanced pre-cancerous lesions. Also, we found that the stool (glyco)proteome of pre-cancerous lesions is enriched for protein species involved in key biological processes linked to humoral and innate immune responses. This study offers a thorough analysis of the stool glycoproteome, laying the groundwork for harnessing glycosylation alterations to improve non-invasive cancer detection.


Asunto(s)
Neoplasias Colorrectales , Lesiones Precancerosas , Humanos , Neoplasias Colorrectales/diagnóstico , Hiperplasia , Carcinogénesis , Antígenos Virales de Tumores
4.
Int J Mol Sci ; 25(6)2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38542435

RESUMEN

Muscle-invasive bladder cancer (MIBC) remains a pressing health concern due to conventional treatment failure and significant molecular heterogeneity, hampering the development of novel targeted therapeutics. In our quest for novel targetable markers, recent glycoproteomics and bioinformatics data have pinpointed (glucose transporter 1) GLUT1 as a potential biomarker due to its increased expression in tumours compared to healthy tissues. This study explores this hypothesis in more detail, with emphasis on GLUT1 glycosylation patterns and cancer specificity. Immunohistochemistry analysis across a diverse set of human bladder tumours representing all disease stages revealed increasing GLUT1 expression with lesion severity, extending to metastasis, while remaining undetectable in healthy urothelium. In line with this, GLUT1 emerged as a marker of reduced overall survival. Revisiting nanoLC-EThcD-MS/MS data targeting immature O-glycosylation on muscle-invasive tumours identified GLUT1 as a carrier of short glycosylation associated with invasive disease. Precise glycosite mapping uncovered significant heterogeneity between patient samples, but also common glycopatterns that could provide the molecular basis for targeted solutions. Immature O-glycosylation conferred cancer specificity to GLUT1, laying the molecular groundwork for enhanced targeted therapeutics in bladder cancer. Future studies should focus on a comprehensive mapping of GLUT1 glycosites for highly specific cancer-targeted therapy development for bladder cancer.


Asunto(s)
Espectrometría de Masas en Tándem , Neoplasias de la Vejiga Urinaria , Humanos , Glicosilación , Transportador de Glucosa de Tipo 1/metabolismo , Neoplasias de la Vejiga Urinaria/metabolismo , Vejiga Urinaria/patología
5.
Adv Exp Med Biol ; 1443: 33-61, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38409415

RESUMEN

Mass spectrometry (MS) is a powerful analytical technique that plays a central role in modern protein analysis and the study of proteostasis. In the field of advanced molecular technologies, MS-based proteomics has become a cornerstone that is making a significant impact in the post-genomic era and as precision medicine moves from the research laboratory to clinical practice. The global dissemination of COVID-19 has spurred collective efforts to develop effective diagnostics, vaccines, and therapeutic interventions. This chapter highlights how MS seamlessly integrates with established methods such as RT-PCR and ELISA to improve viral identification and disease progression assessment. In particular, matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS) takes the center stage, unraveling intricate details of SARS-CoV-2 proteins, revealing modifications such as glycosylation, and providing insights critical to formulating therapies and assessing prognosis. However, high-throughput analysis of MALDI data presents challenges in manual interpretation, which has driven the development of programmatic pipelines and specialized packages such as MALDIquant. As we move forward, it becomes clear that integrating proteomic data with various omic findings is an effective strategy to gain a comprehensive understanding of the intricate biology of COVID-19 and ultimately develop targeted therapeutic paradigms.


Asunto(s)
COVID-19 , Proteómica , Humanos , Proteómica/métodos , COVID-19/diagnóstico , SARS-CoV-2 , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Proteínas , Prueba de COVID-19
6.
Anal Chim Acta ; 1288: 342165, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38220297

RESUMEN

BACKGROUND: Cancer is a leading cause of death worldwide, with metastasis playing a significant role. Circulating Tumour Cells (CTCs) can provide important real-time insights into tumour heterogeneity and clonal evolution, making them an important tool for early diagnosis and patient monitoring. Isolated CTCs are typically identified by immunocytochemistry using positive biomarkers (cytokeratin) and exclusion biomarkers (CD45). However, some white blood cell (WBC) populations can express low levels of CD45 and stain non-specifically for cytokeratin, increasing their risk of misclassification as CTCs. There is a clear need to improve CTC detection and enumeration criteria to unequivocally eliminate interfering WBC populations. RESULTS: This study showed that, indeed, some granulocyte subpopulations expressed low levels of CD45 and stained non-specifically for cytokeratin, misidentifying them as CTCs. These same cells, however, strongly expressed CD15, allowing them to be identified as WBCs and excluded from CTC classification. Flow cytometry confirmed the specificity of the CD15 antibody for the granulocyte subpopulation. False positives were considerably reduced from 25 % to 0.2 % by double exclusion, combining a CD15 antibody with a highly specific CD45 antibody. Furthermore, complete elimination of potential false positives was achieved using double exclusion in combination with improved selection of cytokeratin antibody. The study emphasises the importance of a robust exclusion criteria and high antibody specificity in CTC immuno-assays for accurate identification of CTC candidates and thorough exclusion of interfering WBC subpopulations. SIGNIFICANCE: This study demonstrated how misidentifying a granulocyte subpopulation can lead to inaccurate CTC evaluation. However, sensitivity and specificity of CTC identification may be improved by using high-performing antibodies and by including a second exclusion biomarker, in turn, allowing for a more comprehensive clinical application of CTCs.


Asunto(s)
Biomarcadores de Tumor , Células Neoplásicas Circulantes , Humanos , Células Neoplásicas Circulantes/patología , Citometría de Flujo , Queratinas
7.
J Photochem Photobiol B ; 250: 112834, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38157703

RESUMEN

The rise in antifungal resistance and side effects of conventional treatments drive the search for innovative therapies like Photodynamic Therapy (PDT). This study explored the efficacy of PDT mediated by gutiferone, an isolated compound from red propolis, for candidiasis treatment. Multiple evaluation methods were employed, including determining the minimum inhibitory concentration (MIC) via broth microdilution, quantifying biomass using crystal violet detachment, and cell counting through total plate count. PDT mediated by gutiferone was also assessed in five groups of mice, followed by histopathological examination and agar plating of lingual tissue samples. Among the seven Candida species tested, gutiferone displayed efficacy against C. albicans, C. glabrata, and C. tropicalis, with MIC values of 1000 µg/mL. In C. tropicalis biofilms, exposure to gutiferone led to a reduction of 1.61 Log10 CFU/mL. PDT mediated by gutiferone achieved an average reduction of 3.68 Log10 CFU/mL in C. tropicalis biofilm cells, underscoring its potent fungicidal activity. Histopathological analysis revealed fungal structures, such as pseudohyphae and hyphae, in infected groups (G2) and irradiated mice. In contrast, groups treated with gutiferone or subjected to gutiferone-assisted PDT (G5) exhibited only few blastoconidia. Furthermore, CFU/mL assessments in lingual tissue post-treatment demonstrated a significantly lower count (0.30 Log10 CFU/mL) in the G5 group compared to G2 (2.43 Log10 CFU/mL). These findings highlight the potential of PDT mediated by gutiferone as a promising alternative for managing denture stomatitis. Future research and clinical investigations offer the promise of validating its clinical applicability and improving outcomes in the treatment of oral candidiasis.


Asunto(s)
Candidiasis Bucal , Fotoquimioterapia , Animales , Ratones , Candidiasis Bucal/tratamiento farmacológico , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Candida albicans , Fotoquimioterapia/métodos , Candida , Pruebas de Sensibilidad Microbiana , Biopelículas
8.
Endocrine ; 82(3): 673-680, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37624475

RESUMEN

PURPOSE: This cross-sectional study aimed to assess bone mineral density (BMD), bone microarchitecture and fracture prevalence in women with chronic postsurgical hypoparathyroidism (hypoPT). METHODS: Twenty-seven women with postsurgical hypoPT and 44 age-matched healthy women were included. Dual-energy X-ray absorptiometry was used to evaluate areal BMD and vertebral fracture assessment. High-resolution peripheral quantitative computed tomography assessed microarchitecture and volumetric BMD at the distal radius and tibia. Biochemical parameters, including fibroblast growth factor 23, C-terminal cross-linking telopeptide of type I collagen (ICTP), and procollagen type I N-terminal propeptide (P1NP), were also measured. Previous low-impact fractures were assessed and the 10-year fracture risk was estimated using the FRAX tool for the Brazilian population. RESULTS: No participant had prevalent clinical fractures, and both groups showed low risk for major and hip based on FRAX tool, but two hypoPT patients had moderate to severe morphometric vertebral fractures. Women with hypoPT had increased aBMD in the lumbar spine, femoral neck and total hip (p < 0.05) and higher cortical vBMD in the radius (p = 0.020) and tibia (p < 0.001). Trabecular bone was not affected. Both P1NP and ICTP suggested low bone turnover rates, but no significant correlation was observed between bone density or microstructure and any of the biochemical parameters. CONCLUSIONS: The prevalence of fragility fractures was low in HypoPT women and compatible with low fracture risk estimated by the FRAX tool. Patients had a higher aBMD and cortical vBMD than those of healthy control women, but the association with decreased bone turnover remains unclear.


Asunto(s)
Fracturas Óseas , Hipoparatiroidismo , Fracturas de la Columna Vertebral , Humanos , Femenino , Estudios Transversales , Densidad Ósea , Fracturas Óseas/epidemiología , Absorciometría de Fotón , Fracturas de la Columna Vertebral/diagnóstico por imagen , Fracturas de la Columna Vertebral/epidemiología , Fracturas de la Columna Vertebral/etiología , Tomografía Computarizada por Rayos X/métodos , Radio (Anatomía)/diagnóstico por imagen , Hipoparatiroidismo/diagnóstico por imagen , Hipoparatiroidismo/epidemiología , Hueso Cortical
9.
An Acad Bras Cienc ; 95(suppl 1): e20220914, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37585970

RESUMEN

Zinc (Zn) is an essential micronutrient involved in the physiology of nervous system and pain modulation. There is little evidence for the role of nutritional Zn alternations to the onset and progression of neuropathic (NP) and inflammatory pain. The study investigated the effects of a zinc restricted diet on the development of pain. Weaned mice were submitted to a regular (38 mg/kg of Zn) or Zn deficient (11 mg/kg of Zn) diets for four weeks, pain responses evaluated (mechanical, cold and heat allodynia; formalin- and carrageenan-induced inflammatory hypernociception), plasma and tissues collected for biochemical and metabolomic analysis. Zn deficient diet inhibited animal growth (37%) and changed mice sensitivity pattern, inducing an intense allodynia evoked by mechanical, cold and heat stimulus for four weeks. The inflammatory pain behavior of formalin test was drastically reduced or absent when challenged by an inflammatory stimulus. Zn restriction also reduce plasma TNF, increase neuronal activation, oxidative stress, indicating a disruption of the immune response. Liver metabolomic analyses suggest a downregulation of lipid metabolism of arachidonic acid. Zn restriction since weaned disrupts pain signaling considerably and reduce inflammatory pain. Zn could be considered a predisposing factor for the onset of chronic pain such as painful neuropathies.


Asunto(s)
Hiperalgesia , Desnutrición , Animales , Ratones , Nocicepción , Dolor , Hígado , Zinc/farmacología
10.
Int J Mol Sci ; 24(13)2023 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-37446201

RESUMEN

Colorectal cancer (CRC) ranks as the third most prevalent cancer worldwide. Early detection of this neoplasia has proven to improve prognosis, resulting in a 90% increase in survival. However, available CRC screening methods have limitations, requiring the development of new tools. MicroRNA biomarkers have emerged as a powerful screening tool, as they are highly expressed in CRC patients and easily detectable in several biological samples. While microRNAs are extensively studied in blood samples, recent interest has now arisen in other samples, such as stool samples, where they can be combined with existing screening methods. Among the microRNAs described in the literature, microRNA-21-5p and microRNA-92a-3p and their cluster have demonstrated high potential for early CRC screening. Furthermore, the combination of multiple microRNAs has shown improved performance in CRC detection compared to individual microRNAs. This review aims to assess the available data in the literature on microRNAs as promising biomarkers for early CRC screening, explore their advantages and disadvantages, and discuss the optimal study characteristics for analyzing these biomarkers.


Asunto(s)
Neoplasias Colorrectales , MicroARNs , Humanos , MicroARNs/genética , Biomarcadores de Tumor/genética , Detección Precoz del Cáncer/métodos , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/genética
11.
Artículo en Portugués | LILACS, BDENF - Enfermería, SaludCR | ID: biblio-1430294

RESUMEN

Introdução: O nascimento tem experimentado mudanças na compreensão do parto como processo natural, tornando-o passível de intervenções, como as relacionadas a abreviação do parto através do uso de medicamentos. Objetivo: Descrever o perfil da assistência às gestantes, verificando a prevalência do uso de medicamentos, instrumentos e protocolos, durante o trabalho de parto e parto, em maternidade pública de saúde, destinada à assistência a gestantes de risco habitual. Método: Estudo transversal, descritivo, exploratório e quantitativo, com população por conveniência (n=26 profissionais de saúde). Foram investigadas as características sociodemográficas dos enfermeiros e médicos que prestavam assistência direta ao parto, além daquelas relativas ao uso de medicamentos, instrumentos e protocolos. Os dados foram tabulados no Epiinfo 7.2.2.2, sendo realizada análise estatística descritiva. Resultados: Observou-se que 53,8% são enfermeiros obstetras e 46,2% médicos obstetras. Dentre os entrevistados: 65,4% asseguraram preencher sempre ou quase sempre o partograma, 61,6% aplicam sempre ou quase sempre o índice de Bishop, 57,7% fazem uso de medicamentos para induzir o parto. A prevalência de profissionais que afirmaram não existir protocolos assistenciais ao parto na instituição somou 80,8%. Conclusão: O presente estudo foi relevante para demonstrar que a maioria dos profissionais não usavam medicamentos aceleradores do trabalho de parto; consideravam a integridade das membranas antes da indução medicamentosa, com maior prevalência de uso da ocitocina em relação ao misoprostol nos casos de necessidade de indução com iguais condições do colo uterino. A maior parte dos profissionais afirmou ainda fazer uso de protocolos de assistência ao parto, embora não fossem os institucionais.


Introducción: El nacimiento ha experimentado cambios en la comprensión del parto como un proceso natural, haciéndolo susceptible de intervenciones, como las relacionadas con la abreviación del parto mediante el uso de medicamentos. Objetivo: Describir el perfil de atención de la gestante, para verificar la prevalencia del uso de medicamentos, instrumentos y protocolos durante el trabajo de parto y parto en una maternidad de la red pública de salud, destinada a la asistencia de gestantes de riesgo habitual. Método: Estudio transversal, descriptivo, exploratorio y cuantitativo con población (n=26 profesionales de la salud). Se investigaron las características sociodemográficas de profesionales de enfermería y profesionales médicos que ofrecían asistencia directa durante el parto, además de las relacionadas con el uso de medicamentos, instrumentos y protocolos. Los datos se tabularon en el programa Epiinfo 7.2.2.2 y se realizó el análisis estadístico descriptivo. Resultados: Se observó que el 53.8 % son personal de enfermería obstetricia y el 46.2 % son obstetras. Entre las entrevistadas, el 65.4 % aseguró que siempre o casi siempre completaba el partograma, el 61.6 % siempre o casi siempre aplicaba el índice de Bishop, el 57.7 % utilizaba medicación para inducir el parto. La prevalencia de profesionales que afirmaron que no existían protocolos de atención del parto en la institución fue de 80.8 %. Conclusión: El presente estudio fue relevante para demostrar que la mayoría de los profesionales no utilizaban fármacos para acelerar el trabajo de parto, consideraron la integridad de las membranas antes de la inducción medicamentosa, con mayor prevalencia de uso de oxitocina, en relación al misoprostol en casos de necesidad de inducción con las mismas condiciones del cuello uterino. La mayoría de los profesionales dijeron que todavía hacen uso de los protocolos de atención al parto, aunque no sean institucionales.


Introduction: Birth has experienced changes in the understanding of childbirth as a natural process, making it amenable to interventions, such as those related to shorten the labor time by medication. Objective: To describe the prevalence of the use of drugs, instruments, and protocols in the labor and delivery profile of assistance in a public maternity hospital that nurses low risk pregnancies. Method: This is a cross-sectional, descriptive, exploratory, and quantitative study with population (n=26 health professionals). The sociodemographic characteristics of nurses and doctors who provide direct assistance during childbirth were analyzed in addition to those related to the use of medications, instruments, and protocols. Data were tabulated in the Epiinfo 7.2.2.2 program; then, a descriptive statistical analysis was performed. Results: It was observed that 53.8% are obstetric nurses and 46.2% are obstetricians. Among the interviewees: 65.4% assured that they always or almost always completed the partograph, 61.6% always or almost always applied the Bishop index, 57.7% used medication to induce labor. The prevalence of professionals who stated that there were no childbirth care protocols in the institution totaled 80.8%. Conclusion: The present study was relevant to demonstrate that most professionals did not use drugs for labor induction; they considered the integrity of the membranes before these drugs; and, when induction was needed, there was a higher prevalence of the use of oxytocin in relation to misoprostol in cases with the same conditions of the uterine cervix. Most professionals said that they still use childbirth care protocols although they are not institutional.


Asunto(s)
Humanos , Embarazo , Parto Normal/enfermería , Parto Normal/normas , Brasil , Personal de Salud
13.
Proc Natl Acad Sci U S A ; 120(20): e2214853120, 2023 05 16.
Artículo en Inglés | MEDLINE | ID: mdl-37155874

RESUMEN

Gastric cancer is a dominating cause of cancer-associated mortality with limited therapeutic options. Here, we show that syndecan-4 (SDC4), a transmembrane proteoglycan, is highly expressed in intestinal subtype gastric tumors and that this signature associates with patient poor survival. Further, we mechanistically demonstrate that SDC4 is a master regulator of gastric cancer cell motility and invasion. We also find that SDC4 decorated with heparan sulfate is efficiently sorted in extracellular vesicles (EVs). Interestingly, SDC4 in EVs regulates gastric cancer cell-derived EV organ distribution, uptake, and functional effects in recipient cells. Specifically, we show that SDC4 knockout disrupts the tropism of EVs for the common gastric cancer metastatic sites. Our findings set the basis for the molecular implications of SDC4 expression in gastric cancer cells and provide broader perspectives on the development of therapeutic strategies targeting the glycan-EV axis to limit tumor progression.


Asunto(s)
Neoplasias Gástricas , Sindecano-4 , Humanos , Heparitina Sulfato/metabolismo , Invasividad Neoplásica , Neoplasias Gástricas/genética , Sindecano-4/genética , Sindecano-4/metabolismo
14.
Biophys Chem ; 298: 107027, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37172417

RESUMEN

The crystallographic B-factor, also called temperature factor or Debye-Waller factor, has long been used as a surrogate for local protein flexibility. However, the use of the absolute B-factor as a probe for protein motion requires reproducible validation against conformational changes against chemical and physical variables. Here we report the investigation of the thermal dependence of the crystallographic B-factor and its correlation with conformational changes of the protein. We obtained the crystal protein structure coordinates and B-factors at high resolution (1.5 Å) over a broad temperature range (100 K to 325 K). The exponential thermal dependence of B-factor as a function of temperature was equal for both the diffraction intensity data (Wilson B-factor) and for all modeled atoms of the system (protein and non-protein atoms), with a thermal diffusion constant of about 0.0045 K-1, similar for all atoms. The extrapolated B-factor at zero Kelvin (or zero-point fluctuation) varies among the atoms, although with no apparent correlation with temperature-dependent protein conformational changes. These data suggest that the thermal vibration of the atom does not necessarily correlate with the conformational dynamics of the protein.


Asunto(s)
Proteínas , Temperatura , Conformación Proteica , Cristalografía
15.
Biophys Chem ; 299: 107041, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37257341

RESUMEN

All clinically-used asparaginases convert L-asparagine (L-Asn) to l-aspartate (L-Asp) and l-glutamine (L-Gln) to L-glutamate (L-Glu), which has been useful in reducing bioavailable asparagine and glutamine in patients under treatment for acute lymphoblastic leukemia. The E. coli type 2 L-asparaginase (EcA2) can present different sequences among varying bacterial strains, which we hypothesized that might affect their biological function, stability and interchangeability. Here we report the analysis of two EcA2 provided by the public health system of a middle-income country. These enzymes were reported to have similar specific activity in vitro, whereas they differ in vivo. Protein sequencing by LC-MS-MS and peptide mapping by MALDI-ToF-MS of their tryptic digests revealed that Aginasa™ share similar sequence to EcA2 from E. coli strain BL21(DE3), while Leuginase™ has sequence equivalent to EcA2 from E. coli strain AS1.357. The two amino acid differences between Aginasa™ (64D and 252 T) and Leuginase™ (64 N and 252S) resulted in structural divergences in solution as accessed by small-angle X-ray scattering and molecular dynamics simulation trajectories. The conformational variability further results in dissimilar surface accessibility with major consequences for PEGylation, as well as different susceptibility to degradation by limited proteolysis. The present results reveal that the sequence variations between these two EcA2 variants results in conformational changes associated with differential conformational plasticity, potentially affecting physico-chemical and biological properties, including proteolytic and immunogenic silent inactivation.


Asunto(s)
Asparaginasa , Polietilenglicoles , Leucemia-Linfoma Linfoblástico de Células Precursoras , Humanos , Secuencia de Aminoácidos , Asparaginasa/química , Escherichia coli/genética , Mutación , Polietilenglicoles/química , Polietilenglicoles/metabolismo
16.
Int J Mol Sci ; 24(7)2023 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-37047730

RESUMEN

This study aimed to investigate the influence of genetic variants in neuroplasticity-related genes on antidepressant treatment phenotypes. The BDNF-TrkB signaling pathway, as well as the downstream kinases Akt and ERK and the mTOR pathway, have been implicated in depression and neuroplasticity. However, clinicians still struggle with the unpredictability of antidepressant responses in depressed patients. We genotyped 26 polymorphisms in BDNF, NTRK2, NGFR, CREB1, GSK3B, AKT, MAPK1, MTOR, PTEN, ARC, and SYN1 in 80 patients with major depressive disorder treated according to the Texas Medical Algorithm for 27 months at Hospital Magalhães Lemos, Porto, Portugal. Our results showed that BDNF rs6265, PTEN rs12569998, and SYN1 rs1142636 SNP were associated with treatment-resistant depression (TRD). Additionally, MAPK1 rs6928 and GSK3B rs6438552 gene polymorphisms were associated with relapse. Moreover, we found a link between the rs6928 MAPK1 polymorphism and time to relapse. These findings suggest that the BDNF, PTEN, and SYN1 genes may play a role in the development of TRD, while MAPK1 and GSK3B may be associated with relapse. GO analysis revealed enrichment in synaptic and trans-synaptic transmission pathways and glutamate receptor activity with TRD-associated genes. Genetic variants in these genes could potentially be incorporated into predictive models of antidepressant response.


Asunto(s)
Antidepresivos , Trastorno Depresivo Mayor , Humanos , Antidepresivos/uso terapéutico , Factor Neurotrófico Derivado del Encéfalo/genética , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Trastorno Depresivo Mayor/tratamiento farmacológico , Trastorno Depresivo Mayor/genética , Proteínas del Tejido Nervioso/genética , Fenotipo , Polimorfismo de Nucleótido Simple , Proteínas Proto-Oncogénicas c-akt/genética , Fosfohidrolasa PTEN/genética , Receptores de Factor de Crecimiento Nervioso/genética , Recurrencia , Serina-Treonina Quinasas TOR/genética
17.
Chem Commun (Camb) ; 59(7): 888-891, 2023 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-36598060

RESUMEN

Cyclam-picolinate chelators were functionalized via click chemistry with an additional carboxyl group for subsequent bioconjugation to antibodies or for the modification of the overall charge of the corresponding 64Cu-radiocomplexes. The C-aryl functionalization strategy developed here preserves the chemical properties of the radiocomplexes whilst deeply enhancing their applications within nuclear medicine.


Asunto(s)
Ciclamas , Compuestos Heterocíclicos , Distribución Tisular , Compuestos Heterocíclicos/química , Ácidos Picolínicos , Quelantes/química
19.
São Paulo; s.n; 20221208.
No convencional en Portugués | CONASS, Sec. Est. Saúde SP, SESSP-IDPCPROD, Sec. Est. Saúde SP | ID: biblio-1442507

RESUMEN

INTRODUÇÃO: Pacientes submetidos a cirurgia de Fontan podem apresentar complicações tardias devido a congestão venosa crônica. A criação de fenestrações nos condutos sem fenestrações pode, teoricamente, atenuar a congestão venosa e melhorar as condições clínicas já que leva a aumento do débito cardíaco sistêmico a despeito de leve dessaturação. A literatura é controversa sobre a eficácia deste tipo de procedimento. OBJETIVO: Relatar nossa experiência com a criação percutânea de fenestrações usando uma nova técnica por via trans hepática. MÉTODOS: Estudo observacional de pacientes com complicações tardias de Fontan extra cardíaco não fenestrado (hepatopatia, enteropatia perdedora de proteína, ICC direita). A via transhepática foi obtida por punção percutânea usando fluoroscopia e contraste. Por dentro de uma bainha longa 8Fr uma agulha de punção transeptal foi avançada para perfuração mecânica do conduto. Stents revestidos de 5-7 mm foram usados para criação da fenestração. O ecocardiograma transesofágico (ETE) foi empregado na monitoração. O trajeto hepático foi ocluído com plugs. Anticoagulação vs antiplaquetários ficou a critério clínico. Parâmetros clínicos e laboratoriais foram aplicados no seguimento para avaliar os desfechos. RESULTADOS: Seis pacientes (mediana idade 10 anos) foram submetidos ao procedimento com sucesso e sem complicações. Três deles apresentavam sinais e sintomas de enteropatia perdedora de proteínas (EPP) e os outros ICC direita. Não foram observadas altas pressões no conduto. Um ótimo ângulo de ataque para perfuração na porção inferior do conduto foi obtido em todos os casos. Ao ETE todas as fenestrações apresentavam fluxo adequado D-E pelo stent após implante. A saturação caiu de 92 +/- 3 para 85 +/- 2%. Não houve sangramentos ou hematomas no fígado. Houve melhora clínica inicial em todos os pacientes com redução da congestão venosa. Apesar disto, não houve remissão da EPP nos 3 pacientes (apesar de melhoria laboratorial). Em um destes houve oclusão tardia do stent não sendo possível sua recanalização. CONCLUSÕES: A via trans hepática proporcionou um ótimo ângulo de ataque para criação percutânea de fenestrações com stents em condutos não fenestrados no Fontan. Esta técnica foi segura em nossas mãos, mas sua eficácia foi errática. Estudos adicionais de longo prazo são necessários para avaliar o impacto clínico da criação destas fenestrações nestes difíceis pacientes.


Asunto(s)
Gasto Cardíaco , Procedimiento de Fontan
20.
Medicentro (Villa Clara) ; 26(4): 884-896, oct.-dic. 2022.
Artículo en Español | LILACS | ID: biblio-1405680

RESUMEN

RESUMEN Introducción: Constituye hecho relevante en el ejercicio de la medicina, individual o poblacional, conocer precozmente la instauración de las enfermedades, y por ello se tratan de realizar los diagnósticos clínicos precozmente. Sin embargo, un grupo de enfermedades, infecciosas o no infecciosas, agudas o crónicas, se caracterizan por escasas manifestaciones clínicas, por lo que el conocimiento de su existencia es de vital importancia, por ejemplo, la hipertensión arterial o la diabetes mellitus, cuyas expresiones sintomáticas pueden aparecer tardíamente. En igual medida, la actual pandemia por SARS-CoV-2, ha proliferado rápidamente debido al gran número de personas infectadas que no expresan síntomas. Objetivo: Caracterizar aspectos clínicos relevantes sobre las enfermedades asintomáticas y la importancia de los diagnósticos clínicos o biotecnológicos incipientes, individuales y poblacionales. Métodos: Se realizaron búsquedas bibliográficas de los últimos cinco años en libros clásicos de Medicina Interna, se analizaron artículos publicados en revistas nacionales e internacionales, específicamente en revistas de alto impacto como Lancet y The New England Journal of Medicine. Se consideraron bases de datos de la Organización Mundial de la Salud, así como lo expuesto en Infomed; además se utilizó Google Académico, con los descriptores de interés al respecto. Conclusiones: Por el momento siempre serán parciales, pues se enfatiza en las recomendaciones de la Organización Mundial de la Salud sobre la actual pandemia, para la identificación y control del SARS-CoV-2; se acentúa en la importancia de los métodos clínicos y epidemiológicos, así como en el desarrollo de la biotecnología para el conocimiento de las enfermedades.


ABSTRACT Introduction: early detection of the onset of diseases constitutes a relevant fact in the practice of individual or population medicine that is why early clinical diagnoses are tried to be made. However, a group of infectious or non-infectious, acute or chronic clinical diseases are characterized by few clinical manifestations, for which knowledge of their existence is of vital importance, for example, arterial hypertension or diabetes mellitus, whose symptomatic expressions may appear late. To the same extent, the current SARS-CoV-2 pandemic has proliferated rapidly due to the large number of infected people who do not express symptoms. Objective: to characterize relevant clinical aspects of asymptomatic diseases and the importance of incipient, individual and population clinical or biotechnological diagnoses. Methods: bibliographic searches of the last five years were carried out in classic books on Internal Medicine, articles published in national and international journals were analyzed, specifically in high-impact journals such as the Lancet and The New England Journal of Medicine. Databases of the World Health Organization were considered, as well as what was exposed in Infomed; in addition, Google Scholar was used, with the descriptors of interest in this regard. Conclusions: conclusions will always be partial for the moment, since the recommendations of the World Health Organization for the identification and control of SARS-CoV-2 are emphasized; the importance of clinical and epidemiological methods is highlighted, as well as the development of biotechnology for the knowledge of diseases.


Asunto(s)
Enfermedades Asintomáticas
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