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1.
Gut ; 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38754953

RESUMO

OBJECTIVE: Pancreatic ductal adenocarcinoma (PDAC) has limited therapeutic options, particularly with immune checkpoint inhibitors. Highly chemoresistant 'stem-like' cells, known as cancer stem cells (CSCs), are implicated in PDAC aggressiveness. Thus, comprehending how this subset of cells evades the immune system is crucial for advancing novel therapies. DESIGN: We used the KPC mouse model (LSL-KrasG12D/+; LSL-Trp53R172H/+; Pdx-1-Cre) and primary tumour cell lines to investigate putative CSC populations. Transcriptomic analyses were conducted to pinpoint new genes involved in immune evasion. Overexpressing and knockout cell lines were established with lentiviral vectors. Subsequent in vitro coculture assays, in vivo mouse and zebrafish tumorigenesis studies, and in silico database approaches were performed. RESULTS: Using the KPC mouse model, we functionally confirmed a population of cells marked by EpCAM, Sca-1 and CD133 as authentic CSCs and investigated their transcriptional profile. Immune evasion signatures/genes, notably the gene peptidoglycan recognition protein 1 (PGLYRP1), were significantly overexpressed in these CSCs. Modulating PGLYRP1 impacted CSC immune evasion, affecting their resistance to macrophage-mediated and T-cell-mediated killing and their tumourigenesis in immunocompetent mice. Mechanistically, tumour necrosis factor alpha (TNFα)-regulated PGLYRP1 expression interferes with the immune tumour microenvironment (TME) landscape, promoting myeloid cell-derived immunosuppression and activated T-cell death. Importantly, these findings were not only replicated in human models, but clinically, secreted PGLYRP1 levels were significantly elevated in patients with PDAC. CONCLUSIONS: This study establishes PGLYRP1 as a novel CSC-associated marker crucial for immune evasion, particularly against macrophage phagocytosis and T-cell killing, presenting it as a promising target for PDAC immunotherapy.

2.
Obes Rev ; 25(7): e13758, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38741478

RESUMO

OBJECTIVES: This study assessed the transparency and replicability of exercise-based interventions following bariatric surgery by evaluating the content reporting of exercise-based clinical trials. DESIGN: The study design of the present article is a systematic review. DATA SOURCES: PubMed, Scopus, Web of Sciences, PsycINFO, and Cochrane were searched from their inception to May 2023. ELIGIBILITY CRITERIA: Eligible studies were clinical trials including exercise interventions in participants following bariatric surgery. There were 28 unique exercise interventions. Two independent reviewers applied the exercise prescription components of Frequency, Intensity, Time, and Type (FITT; four items) and the Consensus on Exercise Reporting Template (CERT; 19 items). Exercise interventions were organized into four major exercise components: aerobic training, resistance training, concurrent training, and "others." RESULTS: The FITT assessment revealed that 53% of the trials did not report the training intensity, whereas 25% did not indicate the duration of the major exercise component within the training session. The mean CERT score was 5 out of a possible score of 19. No studies reached CERT score >10, while 13 out of the total 19 CERT items were not adequately reported by ≥75% of the studies. CONCLUSION: This study highlights that the exercise interventions following bariatric surgery are poorly reported, non-transparent, and generally not replicable. This precludes understanding the dose-response association of exercise and health-related effects and requires action to improve this scientific field.


Assuntos
Cirurgia Bariátrica , Terapia por Exercício , Humanos , Terapia por Exercício/métodos , Exercício Físico , Obesidade Mórbida/cirurgia , Treinamento Resistido/métodos
3.
Trials ; 25(1): 288, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38685032

RESUMO

BACKGROUND: Acute kidney injury (AKI) is a significant postoperative complication associated with increased mortality and hospital costs. Hemodynamic strategies, such as goal-directed therapy, might reduce AKI risk. Predicting and proactively managing intraoperative hypotension may be helpful. This trial aims to investigate if a preemptive hemodynamic strategy guided by the hypotension prediction index (HPI) can decrease the incidence of moderate-to-severe AKI within 30 days following major elective abdominal surgery. METHODS: This is an open-label, controlled, multicenter, randomized clinical trial that involves daily patient follow-up until hospital discharge. Inclusion criteria are patients aged over 65 and/or categorized as ASA III or IV physical status, undergoing major elective abdominal surgery (general, urological, or gynecological procedures) via laparoscopic or open approach under general or combined anesthesia. INTERVENTION: In the intervention group, hemodynamic management will be based on the HPI and the advanced functional hemodynamic variables provided by the Hemosphere platform and the AcumenIQ® sensor (Edwards Lifesciences). The primary outcome is the incidence of moderate-to-severe AKI within 7 days post-surgery. Secondary outcomes include postoperative complications and 30-day mortality. DISCUSSION: This study explores the potential of HPI-guided hemodynamic management in reducing AKI after major elective abdominal surgery, with implications for postoperative outcomes and patient care. TRIAL REGISTRATION: ClinicalTrials.gov NCT05569265. Registered on October 6, 2022.


Assuntos
Abdome , Injúria Renal Aguda , Hipotensão , Estudos Multicêntricos como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto , Humanos , Injúria Renal Aguda/prevenção & controle , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/terapia , Injúria Renal Aguda/diagnóstico , Abdome/cirurgia , Hipotensão/prevenção & controle , Hipotensão/etiologia , Procedimentos Cirúrgicos Eletivos , Complicações Pós-Operatórias/prevenção & controle , Complicações Pós-Operatórias/etiologia , Resultado do Tratamento , Feminino , Idoso , Fatores de Tempo , Hemodinâmica , Masculino , Terapia Precoce Guiada por Metas , Fatores de Risco
4.
Eur J Cardiothorac Surg ; 65(4)2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38632054

RESUMO

OBJECTIVES: There is no consensus in the literature on preoperative histological analysis for lung cancer. The objective of this study was to assess 4 diagnostic models used in different hospitals with differing practices regarding preoperative histological diagnosis and the consequences in terms of unnecessary surgery and futile major resection. METHODS: We carried out a retrospective observational study collected from 4 university hospitals in Spain over 3 years (January 2019 to December 2021). We included all patients with a confirmed diagnosis of primary lung cancer and any patients with suspected primary lung cancer who had undergone surgery. All patients underwent computed tomography and positron emission tomography/computed tomography scans. Each multidisciplinary committee was free to choose whether to perform flexible bronchoscopic or transthoracic lung biopsy. Decisions concerning whether to perform intraoperative sample analysis, the surgical approach and the type of resection were left to the surgical team. RESULTS: We included a total of 1642 patients. The use of flexible endoscopy and its diagnostic performance varied substantially between hospitals (range: 23.8-79.3% and 25-60.7%, respectively); and the same was observed for transthoracic biopsy and its performance (range: 16.9-82.3% and 64.6-97%, respectively). Regarding major resection surgery (lobectomy or more extensive resection), the lowest rate was observed in hospital C (1%) and the highest in hospital B (2.8%), with between-hospital differences not reaching significance (P = 0.173). CONCLUSIONS: The rate of histological sampling before lung cancer surgery still varies between hospitals. In spite of very diverse multidisciplinary management, the rate of futile lobectomy is not significantly higher in hospitals with lower rates of preoperative histological analysis.

5.
Adv Healthc Mater ; : e2304150, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38554019

RESUMO

D-mannose is widely used as non-antibiotic treatment for bacterial urinary tract infections. This application is based on a well-studied mechanism of binding to the type 1 bacterial pili and, therefore, blocking bacteria adhesion to the uroepithelial cells. To implement D-mannose into carrier systems, the mechanism of action of the sugar in the bladder environment is also relevant and requires investigation. Herein, two different MANNosylation strategies using mesoporous silica nanoparticles (MSNs) are described. The impact of different chemical linkers on bacterial adhesion and bladder cell response is studied via confocal microscopy imaging of the MSN interactions with the respective organisms. Cytotoxicity is assessed and the expression of Toll-like receptor 4 (TLR4) and caveolin-1 (CAV-1), in the presence or absence of simulated infection with bacterial lipopolysaccharide (LPS), is evaluated using the human urinary bladder cancer cell line T24. Further, localisation of the transcription factor NF-κB due to the MANNosylated materials is examined over time. The results show that MANNosylation modifies bacterial adhesion to the nanomaterials and significantly affects TLR4, caveolin-1, and NF-κB in bladder cells. These elements are essential components of the inflammatory cascade/pathogens response during urinary tract infections. These findings demonstrate that MANNosylation is a versatile tool to design hybrid nanocarriers for targeted biomedical applications.

6.
World Neurosurg X ; 23: 100291, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38523881

RESUMO

Objective: Our primary objective is to evaluate the local control of optic nerve sheath meningiomas (ONSMs) treated with ionizing radiation and related visual changes after treatment. Our secondary objective is to describe the clinical characteristics and perform an analysis of the treatment impact on the functional status of this group of patients. Methods: We present our series of 19 patients treated with ionizing radiation therapy at our radio-neurosurgery unit between 2016 and 2022. The setting, ophthalmological follow-up, morbidity, and survival are analyzed and discussed. Results: Patients were followed up, and the impact of treatment on local disease control, visual alterations of the affected eye, and functional status of the patient were analyzed. The progression-free survival (PFS) median was 60 months (95% CI 50.3-69.6 months). The estimated PFS rates at 48 and 66 months were 100% and 66%, respectively. At diagnosis, nine (47.3%) eyes were in amaurosis and ten (52.6%) with vision. Of the ten patients without amaurosis at the time of diagnosis, three (30%) maintained unchanged visual acuity, and seven (70%) had decreased visual acuity; three of them developed amaurosis during the first year after treatment (p = 0.018). Conclusions: Using ionizing radiation therapy is a successful treatment for the local control of ONSMs. This therapeutic modality can compromise the visual acuity of the affected eye and improve dyschromatopsia and campimetry defects. The life prognosis is good for these patients, with a zero mortality rate, but their vision prognosis is poor.

8.
Food Funct ; 15(9): 4773-4784, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38469873

RESUMO

Raphanus sativus L. cv. Sango, commonly known as red radish, is widely consumed around the world as a vegetable, but its benefit in pain relief is not sufficiently investigated. This study aimed to evaluate the antinociceptive effects of R. sativus and a possible mechanism of action. An aqueous extract of R. sativus sprouts (AERSS) was investigated by parenteral (10, 30, and 100 mg kg-1, i.p.) and enteral (500 mg kg-1, p.o.) administration in the neurogenic and inflammatory phases of the formalin test, where gastric damage was also evaluated as a possible adverse effect. Ketorolac (5 mg kg-1, i.p.) was used as the reference drug. Endogenous opioid and 5-HT1A serotonin receptors, as well as the cAMP/NO-cGMP pathways, were explored in the study of a possible mechanism of action by using their corresponding antagonists: naloxone, 1 mg kg-1, i.p., WAY100635, 1 mg kg-1, i.p., and enzymatic activators or inhibitors, respectively. Sulforaphane (SFN), a known bioactive metabolite, was analyzed using electroencephalography (EEG) to evidence its central involvement. A significant and dose-dependent antinociceptive activity was observed with the AERSS resembling the antinociceptive effect of the reference drug, with an equivalent significant response with a dose of 500 mg kg-1, p.o. without causing gastric damage. The participation of the endogenous opioid and 5-HT1A serotonin receptors at central and peripheral levels was also observed, with a differential participation of cAMP/NO-cGMP. SFN as one metabolite produced significant changes in the EEG analysis, reinforcing its effects on the CNS. Our preclinical evidence supports the benefits of consuming Raphanus sativus cv. Sango sprouts for pain relief.


Assuntos
Analgésicos , Isotiocianatos , Extratos Vegetais , Raphanus , Transdução de Sinais , Animais , Humanos , Masculino , Camundongos , Analgésicos/farmacologia , AMP Cíclico/metabolismo , GMP Cíclico/metabolismo , Isotiocianatos/farmacologia , Dor/tratamento farmacológico , Extratos Vegetais/farmacologia , Raphanus/química , Receptor 5-HT1A de Serotonina/metabolismo , Receptores Opioides/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sulfóxidos/farmacologia
9.
Arch Argent Pediatr ; : e202310141, 2024 Mar 21.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-38484272

RESUMO

Among the causes of chest pain, slipping rib has a low prevalence, usually with a history of trauma, and its management is controversial. Slipping rib syndrome should be included in the differential diagnosis of causes of chest pain in children. When not associated with previous trauma and cartilage deformity, it is necessary to consider an alteration in rib development, regardless of the typical traumatic etiology in adults. Here we describe a series of pediatric patients with slipping rib seen at a referral hospital between 2001 and 2022. Nine patients aged 11 to 16 years were included. Only 2 had a history of trauma. All patients described a sudden onset of severe thoracic abdominal pain. The patients underwent open resection of the affected costal cartilages, with resolution of pain.


Entre las causas de dolor torácico, la costilla deslizante presenta baja prevalencia, antecedentes traumáticos y manejo controvertido. Este síndrome merece ser incluido en el diagnóstico diferencial de causas de dolor torácico en niños. Al no asociarse a traumatismos previos y la deformidad de cartílagos, nos induce a pensar en una alteración en el desarrollo costal, al margen de la etiología traumática típica en adultos. Se presenta una serie de pacientes pediátricos intervenidos por costilla deslizante en un centro de referencia entre 2001 y 2022. Se incluyeron nueve pacientes, con un rango de edades de 11 a 16 años. Solo dos casos describen traumatismo previo. Todos presentan un inicio súbito de dolor toracoabdominal intenso. Los pacientes fueron intervenidos mediante resección abierta de cartílagos costales afectos, con resolución del dolor.

10.
BMC Public Health ; 24(1): 404, 2024 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-38326802

RESUMO

BACKGROUND: To inform the development of an online tool to be potentially used in shared decision-making about breast cancer screening, French women were questioned about participation in breast cancer screening, the health professional's role, and their perceptions of the proposed tool. METHODS: We organised focus group discussions with 55 French women. Two different strategies were used to recruit women from high and low socioeconomic backgrounds. We applied both inductive and deductive approaches to conduct a thematic analysis of the discussions. We analysed the responses by using the main determinants from different health behaviour models and compared the two groups. RESULTS: Independently of socioeconomic status, the most important determinant for a woman's participation in breast cancer screening was the perceived severity of breast cancer and the perceived benefits of its early detection by screening. Cues to action reported by both groups were invitation letters; recommendations by health professionals, or group/community activities and public events were reported by women from high and low socioeconomic backgrounds, respectively. Among other positive determinants, women from high socioeconomic backgrounds reported making informed decisions and receiving peer support whereas women from low socioeconomic backgrounds reported community empowerment through group/community events. Fear of cancer was reported as a barrier in both groups. Among other barriers, language issues were reported only by women from low socioeconomic backgrounds; women from high socioeconomic backgrounds reported breast cancer screening-related risks other than overdiagnosis and/or overtreatment. Barriers to accessing the online tool to be developed were mainly reported by women from high socioeconomic backgrounds. CONCLUSION: Limitations in implementing shared decision-making for women from low socioeconomic backgrounds were highlighted. An online tool that is suitable for all women, regardless of socioeconomic status, would provide "on-demand" reliable and tailored information about breast cancer screening and improve access to health professionals and social exchanges.


Assuntos
Neoplasias da Mama , Feminino , Humanos , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/prevenção & controle , Grupos Focais , Detecção Precoce de Câncer , Pesquisa Qualitativa , Classe Social , Tomada de Decisões , Programas de Rastreamento
11.
Graefes Arch Clin Exp Ophthalmol ; 262(5): 1443-1453, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38197992

RESUMO

PURPOSE: The main purpose of this study was to perform an immunohistochemical, functional, and anatomical evaluation of patients with idiopathic epiretinal membrane (ERM). METHODS: Twenty-four specimens of idiopathic ERM from 24 consecutive patients who underwent 23 G pars plana vitrectomy for ERM and internal limiting membrane (ILM) peeling at the San Juan University Hospital in Alicante (Spain) in 2019 were analyzed. All patients underwent a complete ophthalmological examination including measurement of best corrected visual acuity (BCVA) and macular analysis by spectral-domain optical coherence tomography (SD-OCT) at the time of diagnosis and 3 months after surgery. Specific glial fibrillar acid protein antibodies (GFAP) and S100 calcium-binding protein ß (S100ß) immunostaining markers were used to identify the macroglial component of the ERM, Müller cells, and astrocytes. Ionized calcium-binding adapter molecule 1 protein (Iba1) antibodies were used as specific markers for inflammatory cells, such as microglia and macrophages. RESULTS: Mean preoperative BCVA measured with Snellen chart was 0.3 and 0.6 preoperatively and at 3 months after surgery, respectively. SD-OCT identified 15 patients (62.5%) with a disruption of the outer retinal hyperreflective bands. The immunohistochemical study showed the presence of Müller cells in almost all cases (91.6%), as well of abundant microglia and macrophages. Microglia and macrophages were more frequently present in earlier stages of ERM. Microglia were present in ERM independently of the outer retinal hyperreflective bands integrity as measured by SD-OCT. A greater presence of macrophages was found in those ERMs with no outer retinal hyperreflective band disruption. CONCLUSIONS: Müller cells seem to be the most frequent cell group in ERMs, with also presence of microglia cells and macrophages. Astrocytes were more frequently found in early stages of ERMs. Microglia and macrophages were most frequent in ERMs with early stage (1, 2, or 3) than in advanced stages (4).


Assuntos
Membrana Epirretiniana , Humanos , Membrana Epirretiniana/diagnóstico , Membrana Epirretiniana/cirurgia , Retina , Vitrectomia/métodos , Membrana Basal/cirurgia , Tomografia de Coerência Óptica/métodos , Estudos Retrospectivos
12.
J Exp Clin Cancer Res ; 43(1): 33, 2024 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-38281027

RESUMO

BACKGROUND: Previous studies by our group have shown that oxidative phosphorylation (OXPHOS) is the main pathway by which pancreatic cancer stem cells (CSCs) meet their energetic requirements; therefore, OXPHOS represents an Achille's heel of these highly tumorigenic cells. Unfortunately, therapies that target OXPHOS in CSCs are lacking. METHODS: The safety and anti-CSC activity of a ruthenium complex featuring bipyridine and terpyridine ligands and one coordination labile position (Ru1) were evaluated across primary pancreatic cancer cultures and in vivo, using 8 patient-derived xenografts (PDXs). RNAseq analysis followed by mitochondria-specific molecular assays were used to determine the mechanism of action. RESULTS: We show that Ru1 is capable of inhibiting CSC OXPHOS function in vitro, and more importantly, it presents excellent anti-cancer activity, with low toxicity, across a large panel of human pancreatic PDXs, as well as in colorectal cancer and osteosarcoma PDXs. Mechanistic studies suggest that this activity stems from Ru1 binding to the D-loop region of the mitochondrial DNA of CSCs, inhibiting OXPHOS complex-associated transcription, leading to reduced mitochondrial oxygen consumption, membrane potential, and ATP production, all of which are necessary for CSCs, which heavily depend on mitochondrial respiration. CONCLUSIONS: Overall, the coordination complex Ru1 represents not only an exciting new anti-cancer agent, but also a molecular tool to dissect the role of OXPHOS in CSCs. Results indicating that the compound is safe, non-toxic and highly effective in vivo are extremely exciting, and have allowed us to uncover unprecedented mechanistic possibilities to fight different cancer types based on targeting CSC OXPHOS.


Assuntos
Neoplasias Pancreáticas , Rutênio , Humanos , Fosforilação Oxidativa , Rutênio/farmacologia , Mitocôndrias/metabolismo , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/metabolismo , Células-Tronco Neoplásicas/metabolismo
13.
JCI Insight ; 9(5)2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38271085

RESUMO

High-grade serous carcinoma (HGSC) is the most lethal gynecological malignancy in the United States. Late diagnosis and the emergence of chemoresistance have prompted studies into how the tumor microenvironment, and more recently tumor innervation, may be leveraged for HGSC prevention and interception. In addition to stess-induced sources, concentrations of the sympathetic neurotransmitter norepinephrine (NE) in the ovary increase during ovulation and after menopause. Importantly, NE exacerbates advanced HGSC progression. However, little is known about the role of NE in early disease pathogenesis. Here, we investigated the role of NE in instigating anchorage independence and micrometastasis of preneoplastic lesions from the fallopian tube epithelium (FTE) to the ovary, an essential step in HGSC onset. We found that in the presence of NE, FTE cell lines were able to survive in ultra-low-attachment (ULA) culture in a ß-adrenergic receptor-dependent (ß-AR-dependent) manner. Importantly, spheroid formation and cell viability conferred by treatment with physiological sources of NE were abrogated using the ß-AR blocker propranolol. We have also identified that NE-mediated anoikis resistance may be attributable to downregulation of colony-stimulating factor 2. These findings provide mechanistic insight and identify targets that may be regulated by ovary-derived NE in early HGSC.


Assuntos
Cistadenocarcinoma Seroso , Neoplasias Ovarianas , Feminino , Humanos , Neoplasias Ovarianas/metabolismo , Cistadenocarcinoma Seroso/tratamento farmacológico , Cistadenocarcinoma Seroso/metabolismo , Cistadenocarcinoma Seroso/patologia , Tubas Uterinas/metabolismo , Tubas Uterinas/patologia , Anoikis , Norepinefrina/farmacologia , Norepinefrina/metabolismo , Microambiente Tumoral
14.
Am J Clin Oncol ; 47(2): 58-63, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37853566

RESUMO

BACKGROUND: Studies addressing second hematologic malignancies (SHMs) in patients with primary mediastinal germ cell tumors (PMGCTs) are scarce. To better describe this phenomenon, we analyzed a large case series from a population-based registry. METHODS: The Surveillance, Epidemiology, and End Results database was used to report the clinical characteristics and incidence of SHMs in patients with PMGCT. RESULTS: Among 1297 PMGCTs, 27 cases (2.08%) of SHM were found, with a median latency period of 12 months (95% CI: 5-41). All SHM occurred in males, 20 of whom (74.1%) had a previous nonseminomatous tumor. Acute myeloid leukemia was the most frequent SHM, accounting for 13 cases, 4 of which were acute megakaryoblastic leukemia that occurred within 5 months of diagnosis. The median survival after the diagnosis of SHM was 6 months (95% CI: 2-41). The risk of SHM was significantly higher than expected for the reference population, with a standardized incidence ratio of 6.21 (95% CI: 3.31-10.62) and an absolute excess risk of 19.19 per 10,000 person-years. CONCLUSIONS: Patients with PMGCT are at a higher risk of developing SHMs than the general population, particularly acute myeloid leukemia. This risk ranges from synchronous diagnosis of acute megakaryoblastic leukemia to the later onset of other hematological disorders that might be related to PMGCT therapies. Our findings may help create follow-up schedules for patients with PMGCT and raise the level of suspicion surrounding this association.


Assuntos
Neoplasias Hematológicas , Leucemia Megacarioblástica Aguda , Neoplasias do Mediastino , Neoplasias Embrionárias de Células Germinativas , Segunda Neoplasia Primária , Masculino , Humanos , Neoplasias Hematológicas/epidemiologia , Segunda Neoplasia Primária/epidemiologia , Neoplasias Embrionárias de Células Germinativas/epidemiologia , Neoplasias Embrionárias de Células Germinativas/terapia , Neoplasias do Mediastino/epidemiologia , Neoplasias do Mediastino/patologia
15.
Adv Sci (Weinh) ; 11(4): e2306044, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38032137

RESUMO

The assembly line biosynthesis of the powerful anticancer-antiviral didemnin cyclic peptides is proposed to follow a prodrug release mechanism in Tristella bacteria. This strategy commences with the formation of N-terminal prodrug scaffolds and culminates in their cleavage during the cellular export of the mature products. In this study, a comprehensive exploration of the genetic and biochemical aspects of the enzymes responsible for both the assembly and cleavage of the acylated peptide prodrug scaffolds is provided. This process involves the assembly of N-acyl-polyglutamine moieties orchestrated by the nonribosomal peptide synthetase DidA and the cleavage of these components at the post-assembly stage by DidK, a transmembrane CAAX hydrolase homolog. The findings not only shed light on the complex prodrug mechanism that underlies the synthesis and secretion of didemnin compounds but also offer novel insights into the expanded role of CAAX hydrolases in microbes. Furthermore, this knowledge can be leveraged for the strategic design of genome mining approaches aimed at discovering new bioactive natural products that employ similar prodrug biochemical strategies.


Assuntos
Depsipeptídeos , Pró-Fármacos , Peptídeo Hidrolases , Endopeptidases , Pró-Fármacos/farmacologia
16.
Pediatr. (Asunción) ; 50(3)dic. 2023.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1534957

RESUMO

Introduccion: La Organización Mundial de la Salud (OMS) estima que aproximadamente 100 niños mueren cada hora a causa de lesiones traumáticas. Objetivo: Describir la frecuencia, mecanismos y tipos de traumatismos en los neonatos en el departamento de emergencias pediátricas de un hospital. Materiales y métodos: Estudio observacional, descriptivo, transversal, ambispectivo. Se incluyeron neonatos con diagnóstico de traumatismo que acudieron al departamento de emergencias pediátricas de un hospital desde enero del 2015 a diciembre del 2019. Variables: edad, sexo, procedencia, peso de nacimiento, edad gestacional, tipo de parto, mecanismo y tipo de traumatismo y evolución, Los datos se analizaron en SPSS. El protocolo fue aprobado por el comité de ética. Resultados: Fueron incluidos 90 neonatos, la frecuencia de traumatismo fue del 1,4%, la media de la edad fue de 14,6 ±7,7 días. El 92% nacieron por parto vaginal ,27% macrosómicos. El mecanismo del trauma fue obstétrico en 75,6%, accidentes en la casa 23,3 %y 1 caso de accidente de tránsito. Los tipos de lesiones fueron fracturas de huesos largos, en 47,8%, lesión del plexo braquial 15,5% y traumatismo cráneo encefálico 13,33%. Fueron hospitalizados el 10%. Conclusiones: La frecuencia de traumatismo neonatal en la urgencia pediátrica fue del 1,4%. La edad media fue 14,6 ±7,7dias. El 75,6% fue de origen obstétrico y 23,3% accidentes en la casa y 1 caso de accidente de tránsito. Los tipos de lesiones fueron fracturas de huesos largos, 47,8%, lesión del plexo braquial 15,5% y 13,3% traumatismo cráneo encefálico 13,3%.


Introduction: The World Health Organization (WHO) estimates that approximately 100 children die every hour from traumatic injuries. Objective: To describe the frequency, mechanisms and types of trauma in neonates in the pediatric emergency department of a hospital. Materials and methods: This was an observational, descriptive, transversal, and ambispective study. Neonates with a diagnosis of trauma who presented to the pediatric emergency department of a hospital from January 2015 to December 2019 were included. Variables: age, sex, town of origin, birth weight, gestational age, type of delivery, mechanism and type of trauma and evolution, Data were analyzed in SPSS. The protocol was approved by the ethics committee. Results: 90 neonates were included, the frequency of trauma was 1.4%, the mean age was 14.6 ±7.7 days. 92% were born by vaginal delivery, 27% were macrosomic at birth. The mechanism of trauma was obstetric in 75.6%, accidents at home in 23.3% and there was 1 case of a traffic accident. The types of injuries were long bone fractures, seen in 47.8%, brachial plexus injury in 15.5%, and head trauma in 13.33%. 10% were hospitalized. Conclusions: The frequency of neonatal trauma in the pediatric emergency was 1.4%. The mean age was 14.6 ±7.7 days. 75.6% were obstetric in origin and 23.3% were accidents at home and 1 case of a traffic accident. The types of injuries were long bone fractures in 47.8%, brachial plexus injury in 15.5%, and head trauma in 13.3%.

17.
Mass Spectrom Rev ; 2023 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-37597182

RESUMO

Epigenetic modifications are closely related to certain disorders of the organism, including the development of tumors. One of the main epigenetic modifications is the methylation of DNA cytosines, 5-methyl-2'-deoxycycytidine. Furthermore, 5-mdC can be oxidized to form three new modifications, 5-(hydroxymethyl)-2'-deoxycytidine, 5-formyl-2'-deoxycytidine, and 5-carboxy-2'-deoxycytidine. The coupling of liquid chromatography with tandem mass spectrometry has been widely used for the total determination of methylated DNA cytosines in samples of biological and clinical interest. These methods are based on the measurement of the free compounds (e.g., urine) or after complete hydrolysis of the DNA (e.g., tissues) followed by a preconcentration, derivatization, and/or clean-up step. This review highlights the main advances in the quantification of modified nucleotides and nucleosides by isotope dilution using isotopically labeled analogs combined with liquid or gas chromatography coupled to mass spectrometry reported in the last 20 years. The different possible sources of labeled compounds are indicated. Special emphasis has been placed on the different types of chromatography commonly used (reverse phase and hydrophilic interaction liquid chromatography) and the derivatization methods developed to enhance chromatographic resolution and ionization efficiency. We have also revised the application of bidimensional chromatography and indicated significant biological and clinical applications of these determinations.

18.
Liver Int ; 43(10): 2256-2274, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37534739

RESUMO

BACKGROUND AND AIMS: The mechanisms governing the progression of non-alcoholic fatty liver disease (NAFLD) towards steatohepatitis (NASH) and hepatocellular carcinoma (HCC) remain elusive. Here, we evaluated the role of hsa-miRNA-21-5p in NASH-related hepatocarcinogenesis. METHODS: Hepatic hsa-miR-21-5p expression was evaluated in two cohorts of patients with biopsy-proven NAFLD (n = 199) or HCC (n = 366 HCC and n = 11 NAFLD-HCC). Serum/liver metabolomic profiles were correlated with hsa-miR-21-5p in NAFLD obese patients. Wild-type (WT) and Mir21 KO mice were fed a choline-deficient, amino acid-defined (CDAA) diet for 32 and 66 weeks to induce NASH and NASH-HCC, respectively. RESULTS: In obese individuals, hsa-miR-21-5p expression increased with NAFLD severity and associated with a hepatic lipotoxic profile. CDAA-fed WT mice displayed increased hepatic mmu-miR-21-5p levels and progressively developed NASH and fibrosis, with livers presenting macroscopically discernible pre-neoplastic nodules, hyperplastic foci and deregulated cancer-related pathways. Mir21 KO mice exhibited peroxisome-proliferator-activated receptor α (PPARα) activation, augmented mitochondrial activity, reduced liver injury and NAS below the threshold for NASH diagnosis, with the pro-inflammatory/fibrogenic milieu reversing to baseline levels. In parallel, Mir21 KO mice displayed reduced number of pre-neoplastic nodules, hepatocyte proliferation and activation of oncogenic signalling, being protected from NASH-associated carcinogenesis. The hsa-miRNA-21-5p/PPARα pathway was similarly deregulated in patients with HCC- or NASH-related HCC, correlating with HCC markers and worse prognosis. CONCLUSIONS: Hsa-miR-21-5p is a key inducer of whole-spectrum NAFLD progression, from simple steatosis to NASH and NASH-associated carcinogenesis. The inhibition of hsa-miR-21-5p, leading to a pro-metabolic profile, might constitute an appealing therapeutic approach to ameliorate NASH and prevent progression towards HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , MicroRNAs , Hepatopatia Gordurosa não Alcoólica , Camundongos , Animais , Hepatopatia Gordurosa não Alcoólica/patologia , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , PPAR alfa , Fígado/patologia , Carcinogênese/genética , Carcinogênese/metabolismo , Carcinogênese/patologia , Obesidade/metabolismo , Colina/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo
19.
Pediatr. (Asunción) ; 50(2)ago. 2023.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1507005

RESUMO

Introducción: la utilización de internet conlleva riesgos, como la aparición de las diferentes formas de acoso o ciberbullying. Objetivos: Determinar la frecuencia de diferentes formas de victimización por ciberbullying en adolescentes. Materiales y Métodos: Estudio observacional, descriptivo, prospectivo. Adolescentes de 12 a 18 años edad, que concurrieron al Hospital pediátrico, fueron invitados a participar de una encuesta vía formulario de Google, enviada por WhatsApp, utilizando un cuestionario validado en español en el periodo dé marzo a octubre del 2020. Variables: datos demográficos, exposición a mensajes amenazantes, imágenes humillantes, bromas, rumores, difusión online de información personal o imágenes de índole sexual y segregación del grupo. Los resultados fueron analizados en SPSS. El comité de ética aprobó el estudio con consentimiento informado de los participantes y sus padres. Resultados: Fueron incluidos 406 encuestados, con edad media 15,4±1.99. El 60,1% de sexo femenino, 88,4% de residencia urbana. El 22,5% sufrieron al menos un episodio de ciberbullying. El 19,7% y 26,6% recibieron mensajes amenazantes mensajes y redes sociales respectivamente. El 14,5% fueron humillados con imágenes en internet y el 30,3% con exposición de datos personales. El 10,3% fueron despojados de sus contraseñas. El 7,9 que han sido grabados en situaciones humillantes y el 1% ha sido grabado en situaciones de violencia física. 49,3% de los encuestados han sido apartados del grupo. Conclusión: El 22,5% de los adolescentes fueron objeto de algún tipo de acoso en línea. Los más frecuentes fueron la exposición de información personal y segregación del grupo.


Introduction: the use of the Internet carries risks, such as the appearance of different forms of harassment or cyberbullying. Objectives: To determine the frequency of different forms of cyberbullying victimization in adolescents. Materials and Methods: This was an observational, descriptive and prospective study. Adolescents from 12 to 18 years of age, who consulted at Pediatric Referral Hospital, were invited to participate in a survey via Google form, sent by WhatsApp, using a validated questionnaire in Spanish from March to October 2020. Variables: demographic data, exposure to threatening messages, humiliating images, jokes, rumors, online dissemination of personal information or images of a sexual nature, and exclusion from their peer group. The results were analyzed in SPSS. The ethics committee approved the study with the informed consent of the participants and their parents. Results: 406 respondents were included, with a mean age of 15.4 ± 1.99. 60.1% female, 88.4% urban residence. 22.5% suffered at least one episode of cyberbullying. 19.7% and 26.6% received threatening messages, vía instant messaging and social networks, respectively. 14.5% were humiliated with images on the internet and 30.3% with exposure of personal data. 10.3% were stripped of their passwords. 7.9% have been recorded in humiliating situations and 1% have been recorded in situations of physical violence. 49.3% of those surveyed have been excluded from their peer group. Conclusion : 22.5% of adolescents were subjected to some type of online bullying. The most frequent were the exposure of personal information and exclusion from their peer group.

20.
Pediatr. (Asunción) ; 50(2)ago. 2023.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1507007

RESUMO

Introducción: El pie Bot es la deformidad del pie más frecuente en pediatría. El pie se caracteriza por tener el tobillo equino, varo el retropié, aducto el antepié, y cavo el medio pie. Objetivos: describir la frecuencia y los motivos de abandono del tratamiento del pie Bot en una población pediátrica hospitalaria durante la pandemia (2020-2021). Materiales y Métodos: Estudio observacional descriptivo ambispectivo. Fueron incluidos por muestreo de casos consecutivos, niños de 0 a 6 años que se encontraban en seguimiento de pie Bot en el servicio de traumatología pediátrica y abandonaron el tratamiento. Los datos fueron recogidos de las historias clínicas y por entrevista telefónica con los padres. Variables demográficas, características de la deformidad, edad y escolaridad de la madre, antecedentes familiares de pie Bot y otras malformaciones, la recurrencia, causas del abandono de tratamiento. Los datos fueron analizados en SPSS v21.Se solicitó el consentimiento informado de los padres. Resultados : El 25% (101/404) de los pacientes en seguimiento en el hospital, en el periodo de 2020-2021 abandonaron el tratamiento. Ingresaron al estudio 62 pacientes. El 95% presentaron recurrencia y recibieron tratamiento quirúrgico. La causa más frecuente de abandono del tratamiento de acuerdo con los padres fueron las dificultades derivadas de la pandemia. Conclusiones: La frecuencia de abandono de tratamiento fue del 25,2%, con predominio del sexo masculino. El 95% presentaron recaída y recibieron tratamiento quirúrgico (Tenotomía de Aquiles). La causa más frecuente de abandono de tratamiento fue la pandemia.


Introduction: Clubfoot is the most frequent foot deformity in pediatrics. The foot is characterized by having an equine ankle, a varus hindfoot, an adducted forefoot, and a dig in the midfoot. Objectives: to describe the frequency and reasons for abandoning Clubfoot treatment in a pediatric hospital population in the pandemic (2020-2021). Materials and Methods: This was an ambispective, descriptive and observational study. Consecutive case sampling included children from 0 to 6 years of age who were undergoing Clubfoot follow-up in the pediatric trauma service and abandoned treatment. Data were collected from medical records and by telephone interview with parents. The variables were: demographics, characteristics of the deformity, age and education of the mother, family history of Clubfoot and other malformations, recurrence and causes of treatment abandonment. Data were analyzed in SPSS v21. Parental informed consent was requested. Results: During the 2020-2021 period, 25% (101/404) of the patients being monitored at the hospital abandoned treatment. 62 patients were enrolled in the study. 95% presented recurrence and received surgical treatment. The most frequent cause of treatment abandonment, according to the parents, was the difficulties caused by the pandemic. Conclusions: The frequency of treatment abandonment was 25.2%, with a predominance of males. 95% presented relapse and received surgical treatment (Achilles Tenotomy). The most frequent cause of treatment abandonment was the pandemic.

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