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1.
Brain Behav Immun ; 116: 140-149, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38070619

RESUMEN

Cancers of the central nervous system (CNS) are unique with respect to their tumor microenvironment. Such a status is due to immune-privilege and the cellular behaviors within a highly networked, neural-rich milieu. During tumor development in the CNS, neural, immune and cancer cells establish complex cell-to-cell communication networks which mimic physiological functions, including paracrine signaling and synapse-like formations. This crosstalk regulates diverse pathological functions contributing to tumor progression. In the CNS, regulation of physiological and pathological functions relies on various cell signaling and transcription programs. At the core of these events lies the cyclic adenosine monophosphate (cAMP) response element binding protein (CREB), a master transcriptional regulator in the CNS. CREB is a kinase inducible transcription factor which regulates many CNS functions, including neurogenesis, neuronal survival, neuronal activation and long-term memory. Here, we discuss how CREB-regulated mechanisms operating in diverse cell types, which control development and function of the CNS, are co-opted in CNS tumors.


Asunto(s)
Proteína de Unión a Elemento de Respuesta al AMP Cíclico , Neoplasias , Humanos , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Transducción de Señal/fisiología , Sistema Nervioso Central/metabolismo , Inmunidad , Microambiente Tumoral
2.
Exp Cell Res ; 431(1): 113743, 2023 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-37591452

RESUMEN

A critical challenge in the treatment of glioblastoma (GBM) is its highly invasive nature which promotes cell migration throughout the brain and hinders surgical resection and effective drug delivery. GBM cells demonstrate augmented invasive capabilities following exposure to the current gold standard treatment of radiotherapy (RT) and concomitant and adjuvant temozolomide (TMZ), resulting in rapid disease recurrence. Elucidating the mechanisms employed by post-treatment invasive GBM cells is critical to the development of more effective therapies. In this study, we utilized a Nanostring® Cancer Progression gene expression panel to identify candidate genes that may be involved in enhanced GBM cell invasion after treatment with clinically relevant doses of RT/TMZ. Our findings identified thrombospondin-1 (THBS1) as a pro-invasive gene that is upregulated in these cells. Immunofluorescence staining revealed that THBS1 localised within functional matrix-degrading invadopodia that formed on the surface of GBM cells. Furthermore, overexpression of THBS1 resulted in enhanced GBM cell migration and secretion of MMP-2, which was reduced with silencing of THBS1. The preliminary data demonstrates that THBS1 is associated with invadopodia in GBM cells and is likely involved in the invadopodia-mediated invasive process in GBM cells exposed to RT/TMZ treatment. Therapeutic inhibition of THBS1-mediated invadopodia activity, which facilitates GBM cell invasion, should be further investigated as a treatment for GBM.


Asunto(s)
Glioblastoma , Podosomas , Humanos , Glioblastoma/genética , Glioblastoma/terapia , Recurrencia Local de Neoplasia , Temozolomida/farmacología , Encéfalo
3.
J Exerc Sci Fit ; 22(3): 194-201, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38559906

RESUMEN

Background: Insomnia and depression are prevalent mental disorders that are often comorbid among older adults. Lifestyle intervention strategies incorporating Tai Chi or conventional exercise have been shown to alleviate symptoms of insomnia and depression. However, the comparative efficacy of these exercise modalities in individuals with both disorders has yet to be determined. Therefore, the aim of this study is to examine the efficacy of Tai Chi and conventional exercise for reducing depressive symptoms in older adults with chronic insomnia and depressive symptoms, when compared to a health education control. Methods: This study is a prospective, assessor-blinded, three-arm, parallel group, randomized controlled trial. Older adults aged ≥60 years with a diagnosis of chronic insomnia and depressive symptoms will be randomly assigned to a Tai Chi, conventional exercise or health education control condition on a 1:1:1 basis. Interventions will last for 3 months, with a 6-month follow-up period. The primary outcome is depressive symptoms, assessed using the Hospital Anxiety and Depression Scale. Secondary outcomes include subjective sleep quality, 7-day actigraphy, 7-day sleep diary, anxiety symptoms, quality of life, medication usage and physical function. All measurements will be conducted at baseline, 3 months and 9 months by outcome assessors who are blinded to group allocation. Discussion: This study will compare the efficacy of Tai Chi and conventional exercise in improving depression outcomes in older adults with chronic insomnia and depressive symptoms. Our results will shed light on the clinical potential of these interventions for combating insomnia and depression in older adults.

4.
Mol Cell Biochem ; 478(6): 1251-1267, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36302993

RESUMEN

Glioblastoma (GBM) is the most prevalent primary central nervous system tumour in adults. The lethality of GBM lies in its highly invasive, infiltrative, and neurologically destructive nature resulting in treatment failure, tumour recurrence and death. Even with current standard of care treatment with surgery, radiotherapy and chemotherapy, surviving tumour cells invade throughout the brain. We have previously shown that this invasive phenotype is facilitated by actin-rich, membrane-based structures known as invadopodia. The formation and matrix degrading activity of invadopodia is enhanced in GBM cells that survive treatment. Drug repurposing provides a means of identifying new therapeutic applications for existing drugs without the need for discovery or development and the associated time for clinical implementation. We investigate several FDA-approved agents for their ability to act as both cytotoxic agents in reducing cell viability and as 'anti-invadopodia' agents in GBM cell lines. Based on their cytotoxicity profile, three agents were selected, bortezomib, everolimus and fludarabine, to test their effect on GBM cell invasion. All three drugs reduced radiation/temozolomide-induced invadopodia activity, in addition to reducing GBM cell viability. These drugs demonstrate efficacious properties warranting further investigation with the potential to be implemented as part of the treatment regime for GBM.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Humanos , Glioblastoma/metabolismo , Reposicionamiento de Medicamentos , Neoplasias Encefálicas/metabolismo , Línea Celular Tumoral , Temozolomida/farmacología
5.
BMC Anesthesiol ; 23(1): 112, 2023 04 03.
Artículo en Inglés | MEDLINE | ID: mdl-37013472

RESUMEN

BACKGROUND: Postoperative pain control can be challenging in patients undergoing hepatectomy. A previous retrospective study on hepatobiliary/ pancreatic surgeries showed better postoperative pain control in patients who received propofol TIVA. The aim of this study was to determine the analgesic effect of propofol TIVA for hepatectomy. This clinical study has been registered at ClinicalTrials.gov (NCT03597997). METHODS: A prospective randomized controlled trial was performed to compare the analgesic effect of propofol TIVA versus inhalational anaesthesia. Patients aged between 18 and 80 years old with an American Society of Anesthesiologist (ASA) physical status of I-III scheduled for elective hepatectomy were recruited. Ninety patients were randomly allocated to receive either propofol TIVA (TIVA group) or inhalational anaesthesia with sevoflurane (SEVO group). Perioperative anaesthetic/analgesic management was the same for both groups. Numerical rating scale (NRS) pain scores, postoperative morphine consumption, quality of recovery, patient satisfaction and adverse effects were evaluated during the acute postoperative period and at 3 and 6 months after surgery. RESULTS: No significant differences were found for acute postoperative pain scores (both at rest and during coughing) and postoperative morphine consumption between TIVA and SEVO groups. Patients given TIVA had lower pain scores with coughing at 3 months after surgery (p = 0.014, and FDR < 0.1). TIVA group was associated with better quality of recovery on postoperative day (POD) 3 (p = 0.038, and FDR < 0.1), less nausea (p = 0.011, and FDR < 0.1 on POD 2; p = 0.013, and FDR < 0.1 on POD 3) and constipation (p = 0.013, and FDR < 0.1 on POD 3). CONCLUSION: Propofol TIVA did not improve acute postoperative pain control compared to inhalational anaesthesia in patients who underwent hepatectomy. Our results do not support the use of propofol TIVA for reducing acute postoperative pain after hepatectomy.


Asunto(s)
Anestésicos por Inhalación , Propofol , Humanos , Adolescente , Adulto Joven , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Anestésicos Intravenosos , Anestesia Intravenosa/métodos , Hepatectomía/efectos adversos , Estudios Prospectivos , Dolor Postoperatorio/tratamiento farmacológico , Dolor Postoperatorio/prevención & control , Dolor Postoperatorio/inducido químicamente , Analgésicos/uso terapéutico , Derivados de la Morfina/uso terapéutico
6.
Int J Mol Sci ; 24(24)2023 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-38139284

RESUMEN

Multiple sclerosis (MS) is a neurodegenerative disease marked by chronic neuroinflammation thought to be mediated by the inflammasome pathway. Connexin 43 (Cx43) hemichannels contribute to the activation of the inflammasome through the release of adenosine triphosphate (ATP) inflammasome activation signals. The objective of the study was to evaluate if the Cx43 hemichannel blocker, tonabersat, is effective in modulating the inflammatory response and reducing disability in the myelin oligodendrocyte glycoprotein 35-55-induced experimental autoimmune encephalomyelitis (MOG35-55 EAE) model of MS. Here, we show that the Cx43 hemichannel blocking drug, tonabersat, significantly reduced expression of neuroinflammatory markers for microglial activation (ionized calcium-binding adapter molecule 1 (Iba1)) and astrogliosis (glial fibrillary acidic protein (GFAP)) while preserving myelin basic protein (MBP) expression levels in the corpus callosum, motor cortex, and striatum regions of the brain in MOG35-55 EAE mice. Reduced NOD-like receptor protein 3 (NLRP3) inflammasome complex assembly and Caspase-1 activation confirmed the drug's mode of action. MOG35-55 EAE mice showed clinical signs of MS, but MOG35-55 EAE mice treated with tonabersat retained behavior closer to normal. These data suggest that clinical trial phase IIb-ready tonabersat may merit further investigation as a promising candidate for MS treatment.


Asunto(s)
Encefalomielitis Autoinmune Experimental , Esclerosis Múltiple , Enfermedades Neurodegenerativas , Ratones , Animales , Esclerosis Múltiple/tratamiento farmacológico , Conexina 43/metabolismo , Inflamasomas/metabolismo , Progresión de la Enfermedad , Ratones Endogámicos C57BL , Modelos Animales de Enfermedad
7.
J Clin Psychol Med Settings ; 30(3): 561-569, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-36414787

RESUMEN

Stigma is a strong concern in the effort to manage the impact of many chronic diseases on patients and affects the quality of life (QoL) of patients, but little is understood regarding how this happens. We explored the perspective that stigma reduces health-related QoL (HRQoL) by evoking the traumatic experiences associated with HIV diagnosis. Outpatients (n = 250) receiving HIV-related care were recruited from 2 hospitals in the southeastern region of Nigeria. Participants completed measures of stigma, posttraumatic stress symptoms, and HRQoL. Mediation analyses were conducted using Hayes PROCESS Macro for SPSS. Result showed that stigma was negatively associated with HRQoL; patients who reported more traumatic symptoms also reported poorer HRQoL. Traumatic stress symptoms mediated the path between stigma and all the dimensions of HRQoL. Findings suggest that recognizing and addressing trauma symptoms are important in the management of PLWH. Perhaps addressing trauma would reduce the impact of stigma on HRQoL.


Asunto(s)
Infecciones por VIH , Problema de Conducta , Trastornos por Estrés Postraumático , Humanos , Calidad de Vida , Infecciones por VIH/complicaciones , Trastornos por Estrés Postraumático/complicaciones , Estigma Social
8.
J Exerc Sci Fit ; 21(1): 67-73, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36408205

RESUMEN

Background: Insomnia is a prevailing health problem among older adults. Tai Chi, a popular mind-body exercise practiced by older people in various oriental communities, has been shown to improve sleep. However, Tai Chi has not been directly compared to cognitive behavioral therapy for insomnia (CBT-I), which is the first-line non-pharmacological treatment for insomnia in older adults. This study aims to examine whether Tai Chi is non-inferior to CBT-I as a treatment for insomnia in older adults. Methods: This is a single-center, assessor-blinded, non-inferiority randomized controlled trial comparing Tai Chi and CBT-I in 180 older adults aged ≥50 years with chronic insomnia according to the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition. Participants will be randomly assigned to either the Tai Chi or CBT-I group. Interventions will last for 3 months with a 12-month follow-up. The primary outcome is self-perceived insomnia severity measured by Insomnia Severity Index (ISI) at 3 months and at 15 months. The secondary outcomes include the remission rate of chronic insomnia, insomnia treatment response, subjective sleep quantity and quality, 7-day actigraphy, 7-day sleep diary, sleep medication, health-related quality of life, mental health, body balance and lower extremity function, adverse events, habitual physical activity, and dietary intake. Measurements will be conducted at baseline, 3 months, and 15 months by outcome assessors who are blinded to the group allocation. Discussion: This will be the first non-inferiority randomized controlled trial to compare the efficacy and long-term outcomes of Tai Chi versus CBT-I for treating insomnia in older adults. This study will be of clinical importance as it supports the use of Tai Chi as an alternative non-pharmacological approach for insomnia treatment and sustainable management.

9.
Ann Intern Med ; 174(8): 1050-1057, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34058100

RESUMEN

BACKGROUND: Central obesity is a major manifestation of metabolic syndrome, which is a common health problem in middle-aged and older adults. OBJECTIVE: To examine the therapeutic efficacy of tai chi for management of central obesity. DESIGN: Randomized, controlled, assessor-blinded trial. (ClinicalTrials.gov: NCT03107741). SETTING: A single research site in Hong Kong between 27 February 2016 and 28 February 2019. PARTICIPANTS: Adults aged 50 years or older with central obesity. INTERVENTION: 543 participants were randomly assigned in a 1:1:1 ratio to a control group with no exercise intervention (n = 181), conventional exercise consisting of aerobic exercise and strength training (EX group) (n = 181), and a tai chi group (TC group) (n = 181). Interventions lasted 12 weeks. MEASUREMENTS: Outcomes were assessed at baseline, week 12, and week 38. The primary outcome was waist circumference (WC). Secondary outcomes were body weight; body mass index; high-density lipoprotein cholesterol (HDL-C), triglyceride, and fasting plasma glucose levels; blood pressure; and incidence of remission of central obesity. RESULTS: The adjusted mean difference in WC from baseline to week 12 in the control group was 0.8 cm (95% CI, -4.1 to 5.7 cm). Both intervention groups showed reductions in WC relative to control (adjusted mean differences: TC group vs. control, -1.8 cm [CI, -2.3 to -1.4 cm]; P < 0.001; EX group vs. control: -1.3 cm [CI, -1.8 to -0.9 cm]; P < 0.001); both intervention groups also showed reductions in body weight (P < 0.05) and attenuation of the decrease in HDL-C level relative to the control group. The favorable changes in WC and body weight were maintained in both the TC and EX groups, whereas the beneficial effect on HDL-C was only maintained in the TC group at week 38. LIMITATIONS: High attrition and no dietary intervention. CONCLUSION: Tai chi is an effective approach to reduce WC in adults with central obesity aged 50 years or older. PRIMARY FUNDING SOURCE: Health and Medical Research Fund.


Asunto(s)
Ejercicio Físico/fisiología , Obesidad Abdominal/prevención & control , Taichi Chuan , Anciano , Glucemia/metabolismo , Presión Sanguínea , Índice de Masa Corporal , Peso Corporal , HDL-Colesterol/sangre , Femenino , Hong Kong , Humanos , Masculino , Persona de Mediana Edad , Triglicéridos/sangre , Circunferencia de la Cintura
10.
Int J Mol Sci ; 23(5)2022 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-35269915

RESUMEN

Glioblastoma is the most aggressive brain tumour with short survival, partly due to resistance to conventional therapy. Glioma stem cells (GSC) are likely to be involved in treatment resistance, by releasing extracellular vesicles (EVs) containing specific molecular cargoes. Here, we studied the EVs secreted by glioma stem cells (GSC-EVs) and their effects on radiation resistance and glioma progression. EVs were isolated from 3 GSCs by serial centrifugation. NanoSight measurement, cryo-electron microscopy and live imaging were used to study the EVs size, morphology and uptake, respectively. The non-GSC glioma cell lines LN229 and U118 were utilised as a recipient cell model. Wound healing assays were performed to detect cell migration. Colony formation, cell viability and invadopodium assays were conducted to detect cell survival of irradiated recipient cells and cell invasion post GSC-EV treatment. NanoString miRNA global profiling was used to select for the GSC-EVs' specific miRNAs. All three GSC cell lines secreted different amounts of EVs, and all expressed consistent levels of CD9 but different level of Alix, TSG101 and CD81. EVs were taken up by both LN229 and U118 recipient cells. In the presence of GSC-EVs, these recipient cells survived radiation exposure and initiated colony formation. After GSC-EVs exposure, LN229 and U118 cells exhibited an invasive phenotype, as indicated by an increase in cell migration. We also identified 25 highly expressed miRNAs in the GSC-EVs examined, and 8 of these miRNAs can target PTEN. It is likely that GSC-EVs and their specific miRNAs induced the phenotypic changes in the recipient cells due to the activation of the PTEN/Akt pathway. This study demonstrated that GSC-EVs have the potential to induce radiation resistance and modulate the tumour microenvironment to promote glioma progression. Future therapeutic studies should be designed to interfere with these GSC-EVs and their specific miRNAs.


Asunto(s)
Vesículas Extracelulares , Glioma , MicroARNs , Microscopía por Crioelectrón , Vesículas Extracelulares/metabolismo , Glioma/genética , Glioma/metabolismo , Glioma/radioterapia , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Células Madre Neoplásicas/metabolismo , Microambiente Tumoral
11.
Entropy (Basel) ; 24(12)2022 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-36554256

RESUMEN

Harmonic oscillators with multiple abrupt jumps in their frequencies have been investigated by several authors during the last decades. We investigate the dynamics of a quantum harmonic oscillator with initial frequency ω0, which undergoes a sudden jump to a frequency ω1 and, after a certain time interval, suddenly returns to its initial frequency. Using the Lewis−Riesenfeld method of dynamical invariants, we present expressions for the mean energy value, the mean number of excitations, and the transition probabilities, considering the initial state different from the fundamental. We show that the mean energy of the oscillator, after the jumps, is equal or greater than the one before the jumps, even when ω1<ω0. We also show that, for particular values of the time interval between the jumps, the oscillator returns to the same initial state.

12.
Br J Cancer ; 125(11): 1466-1476, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34349251

RESUMEN

The prognosis for patients with glioblastoma (GBM), the most common and malignant type of primary brain tumour, is very poor, despite current standard treatments such as surgery, radiotherapy and chemotherapy. Moreover, the immunosuppressive tumour microenvironment hinders the development of effective immunotherapies for GBM. Cytokines such as interleukin-10 (IL-10) play a major role in modulating the activity of infiltrating immune cells and tumour cells in GBM, predominantly conferring an immunosuppressive action; however, in some circumstances, IL-10 can have an immunostimulatory effect. Elucidating the function of IL-10 in GBM is necessary to better strategise and improve the efficacy of immunotherapy. This review discusses the immunostimulatory and immunosuppressive roles of IL-10 in the GBM tumour microenvironment while considering IL-10-targeted treatment strategies. The molecular mechanisms that underlie the expression of IL-10 in various cell types are also outlined, and how this resulting information might provide an avenue for the improvement of immunotherapy in GBM is explored.


Asunto(s)
Neoplasias Encefálicas/genética , Glioma/genética , Interleucina-10/metabolismo , Progresión de la Enfermedad , Humanos , Pronóstico
13.
Cancer Immunol Immunother ; 70(7): 1811-1820, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33389014

RESUMEN

Recent developments in cancer immunotherapy promise better outcomes for cancer patients, although clinical trials for difficult to treat cancers such as malignant brain cancer present special challenges, showing little response to first generation immunotherapies. Reasons for differences in immunotherapy response in some cancer types are likely due to the nature of tumor microenvironment, which harbors multiple cell types which interact with tumor cells to establish immunosuppression. The cell types which appear to hold the key in regulating tumor immunosuppression are the tumor-infiltrating immune cells. The current standard treatment for difficult to treat cancer, including the most malignant brain cancer, glioblastoma, continues to offer a bleak outlook for patients. Immune-profiling and correlation with pathological and clinical data will lead to a deeper understanding of the tumor immune microenvironment and contribute toward the selection, optimization and development of novel precision immunotherapies. Here, we review the current understanding of the tumor microenvironmental landscape in glioblastoma with a focus on next-generation technologies including multiplex immunofluorescence and computational approaches to map the brain tumor microenvironment to decipher the role of the immune system in this lethal malignancy.


Asunto(s)
Biomarcadores de Tumor/inmunología , Neoplasias Encefálicas/tratamiento farmacológico , Simulación por Computador , Tolerancia Inmunológica/inmunología , Inmunohistoquímica/métodos , Inmunoterapia/métodos , Microambiente Tumoral/inmunología , Animales , Antineoplásicos/uso terapéutico , Biomarcadores de Tumor/metabolismo , Neoplasias Encefálicas/inmunología , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patología , Humanos , Terapia Molecular Dirigida , Medicina de Precisión
14.
Artículo en Inglés | MEDLINE | ID: mdl-33358925

RESUMEN

Anurans have an exceptional capacity for maintaining vascular volume compared with other groups of vertebrates. They can mobilize interstitial fluids via lymphatic return at rates that are ten-fold higher than mammals. This extraordinary capacity is the result of coordination of specialized skeletal muscles and pulmonary ventilation that vary volume and pressure of subcutaneous lymph sacs, thus moving lymph to dorsally located lymph hearts that return lymph to the vascular space. Variation in the capacity to mobilize lymph within anurans varies with the degree of terrestriality, development of skeletal muscles, lung volume and lung compliance, and lymph heart pressure development. This ability enable anurans, which have the highest rates of evaporative water loss among terrestrial vertebrates, to withstand levels of dehydration far exceeding that of other vertebrates, and to successfully occupy virtually all terrestrial environments during their evolution. Maintenance of vascular fluid volume for all vertebrates can be achieved primarily by moving fluid from the interstitial space to the vascular space by transcapillary uptake and mobilization of interstitial (lymphatic) fluid. Transcapillary fluid uptake at the capillary level has been analyzed historically by Krogh and others from a Starling perspective and involves a balance of hydrostatic and oncotic forces. A complete evaluation of blood volume homeostasis also incorporates pressures and compliances of the vascular and interstitial spaces, but has been applied to only a few species. In this review we outline the current understanding of how anurans and other vertebrates maintain blood volume during hypovolemic challenges such as dehydration and hemorrhage which is crucial for maintaining cardiac output.


Asunto(s)
Volumen Sanguíneo/fisiología , Capilares/fisiología , Hipovolemia/metabolismo , Linfa/fisiología , Sistema Linfático/fisiología , Anfibios , Animales , Anuros , Transporte Biológico , Peces , Hemorragia , Humanos , Pulmón/fisiología , Músculo Esquelético/metabolismo , Ventilación Pulmonar , Ranidae , Especificidad de la Especie , Vertebrados , Viscosidad
15.
Reproduction ; 159(3): 289-302, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31990666

RESUMEN

Equine placentitis is associated with alterations in maternal peripheral steroid concentrations, which could negatively affect pregnancy outcome. This study aimed to elucidate the molecular mechanisms related to steroidogenesis and steroid-receptor signaling in the equine placenta during acute placentitis. Chorioallantois (CA) and endometrial (EN) samples were collected from mares with experimentally induced placentitis (n = 4) and un-inoculated gestationally age-matched mares (control group; n = 4). The mRNA expression of genes coding for steroidogenic enzymes (3ßHSD, CYP11A1, CYP17A1, CYP19A1, SRD5A1, and AKR1C23) was evaluated using qRT-PCR. The concentration of these enzyme-dependent steroids (P5, P4, 5αDHP, 3αDHP, 20αDHP, 3ß-20αDHP, 17OH-P, DHEA, A4, and estrone) was assessed using liquid chromatography-tandem mass spectrometry in both maternal circulation and placental tissue. Both SRD5A1 and AKR1C23, which encode for the key progesterone metabolizing enzymes, were downregulated (P < 0.05) in CA from the placentitis group compared to controls, and this downregulation was associated with a decline in tissue concentrations of 5αDHP (P < 0.05), 3αDHP (P < 0.05), and 3ß-20αDHP (P = 0.052). In the EN, AKR1C23 was also downregulated in the placentitis group compared to controls, and this downregulation was associated with a decline in EN concentrations of 3αDHP (P < 0.01) and 20αDHP (P < 0.05). Moreover, CA expression of CYP19A1 tended to be lower in the placentitis group, and this reduction was associated with lower (P = 0.057) concentrations of estrone in CA. Moreover, ESR1 (steroid receptors) gene expression was downregulated (P = 0.057) in CA from placentitis mares. In conclusion, acute equine placentitis is associated with a local withdrawal of progestins in the placenta and tended to be accompanied with estrogen withdrawals in CA.


Asunto(s)
Corioamnionitis/veterinaria , Congéneres del Estradiol/biosíntesis , Caballos/metabolismo , Placenta/enzimología , Progesterona/biosíntesis , Animales , Corioamnionitis/enzimología , Corioamnionitis/patología , Femenino , Placenta/patología , Embarazo
16.
J Natl Compr Canc Netw ; 18(6): 650-655, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32502983

RESUMEN

Erdheim-Chester disease (ECD) is an extremely rare and aggressive non-Langerhans histiocytic disorder. ECD typically presents with bone pain in middle-aged adults, although some patients present with multisystem disease involving the skeleton, central nervous system, cardiovascular system, lungs, and other disease sites. The etiology of ECD is currently unknown, but it is thought to be a reactive or neoplastic disorder. Recently, mutation of the BRAF gene has been found in >50% of ECD cases, and this gene has become a therapeutic target for patients with ECD. Vemurafenib, a BRAF inhibitor, has been approved by the FDA for treatment of ECD. This report presents an elderly male patient with an aggressive phenotype of ECD and highlights the utility of multimodality imaging in monitoring the clinical course and disease response to treatment with vemurafenib.


Asunto(s)
Antineoplásicos/uso terapéutico , Enfermedad de Erdheim-Chester/diagnóstico por imagen , Enfermedad de Erdheim-Chester/tratamiento farmacológico , Imagen Multimodal/métodos , Proteínas Proto-Oncogénicas B-raf/metabolismo , Vemurafenib/uso terapéutico , Antineoplásicos/farmacología , Enfermedad de Erdheim-Chester/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Vemurafenib/farmacología
17.
Philos Trans A Math Phys Eng Sci ; 378(2187): 20190479, 2020 Dec 25.
Artículo en Inglés | MEDLINE | ID: mdl-33161852

RESUMEN

The Voyager 2 flybys of Uranus and Neptune revealed the first multipolar planetary magnetic fields and highlighted how much we have yet to learn about ice giant planets. In this review, we summarize observations of Uranus' and Neptune's magnetic fields and place them in the context of other planetary dynamos. The ingredients for dynamo action in general, and for the ice giants in particular, are discussed, as are the factors thought to control magnetic field strength and morphology. These ideas are then applied to Uranus and Neptune, where we show that no models are yet able to fully explain their observed magnetic fields. We then propose future directions for missions, modelling, experiments and theory necessary to answer outstanding questions about the dynamos of ice giant planets, both within our solar system and beyond. This article is part of a discussion meeting issue 'Future exploration of ice giant systems'.

18.
Exp Cell Res ; 374(2): 353-364, 2019 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-30562483

RESUMEN

Glioblastoma (GBM) tumor cells exhibit drug resistance and are highly infiltrative. GBM stem cells (GSCs), which have low proliferative capacity are thought to be one of the sources of resistant cells which result in relapse/recurrence. However, the molecular mechanisms regulating quiescent-specific tumor cell biology are not well understood. Using human GBM cell lines and patient-derived GBM cells, Oregon Green dye retention was used to identify and isolate the slow-cycling, quiescent-like cell subpopulation from the more proliferative cells in culture. Sensitivity of cell subpopulations to temozolomide and radiation, as well as the migration and invasive potential were measured. Differential expression analysis following RNAseq identified genes enriched in the quiescent cell subpopulation. Orthotopic transplantation of cells into mice was used to compare the in vivo malignancy and invasive capacity of the cells. Proliferative quiescence correlated with better TMZ resistance and enhanced cell invasion, in vitro and in vivo. RNAseq expression analysis identified genes involved in the regulation cell invasion/migration and a three-gene signature, TGFBI, IGFBP3, CHI3L1, overexpressed in quiescent cells which correlates with poor GBM patient survival.


Asunto(s)
Neoplasias Encefálicas/patología , División Celular/fisiología , Resistencia a Antineoplásicos/fisiología , Glioblastoma/patología , Animales , Antineoplásicos/farmacología , Neoplasias Encefálicas/tratamiento farmacológico , División Celular/efectos de los fármacos , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Movimiento Celular/fisiología , Proliferación Celular/efectos de los fármacos , Proliferación Celular/fisiología , Resistencia a Antineoplásicos/efectos de los fármacos , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Glioblastoma/tratamiento farmacológico , Humanos , Ratones , Ratones Endogámicos BALB C , Recurrencia Local de Neoplasia/tratamiento farmacológico , Recurrencia Local de Neoplasia/patología , Células Madre Neoplásicas/efectos de los fármacos , Células Madre Neoplásicas/patología , Temozolomida/farmacología , Ensayos Antitumor por Modelo de Xenoinjerto/métodos
19.
Nature ; 510(7505): 422-426, 2014 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-24814345

RESUMEN

2-Oxoglutarate (2OG)-dependent oxygenases have important roles in the regulation of gene expression via demethylation of N-methylated chromatin components and in the hydroxylation of transcription factors and splicing factor proteins. Recently, 2OG-dependent oxygenases that catalyse hydroxylation of transfer RNA and ribosomal proteins have been shown to be important in translation relating to cellular growth, TH17-cell differentiation and translational accuracy. The finding that ribosomal oxygenases (ROXs) occur in organisms ranging from prokaryotes to humans raises questions as to their structural and evolutionary relationships. In Escherichia coli, YcfD catalyses arginine hydroxylation in the ribosomal protein L16; in humans, MYC-induced nuclear antigen (MINA53; also known as MINA) and nucleolar protein 66 (NO66) catalyse histidine hydroxylation in the ribosomal proteins RPL27A and RPL8, respectively. The functional assignments of ROXs open therapeutic possibilities via either ROX inhibition or targeting of differentially modified ribosomes. Despite differences in the residue and protein selectivities of prokaryotic and eukaryotic ROXs, comparison of the crystal structures of E. coli YcfD and Rhodothermus marinus YcfD with those of human MINA53 and NO66 reveals highly conserved folds and novel dimerization modes defining a new structural subfamily of 2OG-dependent oxygenases. ROX structures with and without their substrates support their functional assignments as hydroxylases but not demethylases, and reveal how the subfamily has evolved to catalyse the hydroxylation of different residue side chains of ribosomal proteins. Comparison of ROX crystal structures with those of other JmjC-domain-containing hydroxylases, including the hypoxia-inducible factor asparaginyl hydroxylase FIH and histone N(ε)-methyl lysine demethylases, identifies branch points in 2OG-dependent oxygenase evolution and distinguishes between JmjC-containing hydroxylases and demethylases catalysing modifications of translational and transcriptional machinery. The structures reveal that new protein hydroxylation activities can evolve by changing the coordination position from which the iron-bound substrate-oxidizing species reacts. This coordination flexibility has probably contributed to the evolution of the wide range of reactions catalysed by oxygenases.


Asunto(s)
Eucariontes/enzimología , Modelos Moleculares , Oxigenasas/química , Células Procariotas/enzimología , Ribosomas/enzimología , Secuencia de Aminoácidos , Dominio Catalítico , Secuencia Conservada , Eucariontes/clasificación , Humanos , Oxigenasas/metabolismo , Filogenia , Células Procariotas/clasificación , Pliegue de Proteína , Estructura Terciaria de Proteína , Alineación de Secuencia
20.
BMC Anesthesiol ; 20(1): 130, 2020 05 28.
Artículo en Inglés | MEDLINE | ID: mdl-32466746

RESUMEN

BACKGROUND: It is unclear whether regional anesthesia with infraclavicular nerve block or general anesthesia provides better postoperative analgesia after distal radial fracture fixation, especially when combined with regular postoperative analgesic medications. The aim of this study was to compare the postoperative analgesic effects of regional versus general anesthesia. METHODS: In this prospective, observer blinded, randomized controlled trial, 52 patients undergoing distal radial fracture fixation received either general anesthesia (n = 26) or regional anesthesia (infraclavicular nerve block, n = 26). Numerical rating scale pain scores, analgesic consumption, patient satisfaction, adverse effects, upper limb functional scores (Patient-Rated Wrist Evaluation, QuickDASH), health related quality of life (SF12v2), and psychological status were evaluated after surgery. RESULT: Regional anesthesia was associated with significantly lower pain scores both at rest and with movement on arrival to the post-anesthetic care unit; and at 1, 2, 24 and 48 h after surgery (p ≤ 0.001 at rest and with movement). Morphine consumption in the post-anesthetic care unit was significantly lower in the regional anesthesia group (p<0.001). There were no differences in oral analgesic consumption. Regional anesthesia was associated with lower incidences of nausea (p = 0.004), and vomiting (p = 0.050). Patient satisfaction was higher in the regional anesthesia group (p = 0.003). There were no long-term differences in pain scores and other patient outcomes. CONCLUSION: Regional anesthesia with ultrasound guided infraclavicular nerve block was associated with better acute pain relief after distal radial fracture fixation, and may be preferred over general anesthesia. TRIAL REGISTRATION: Before subject enrollment, the study was registered at ClinicalTrials.gov (NCT03048214) on 9th February 2017.


Asunto(s)
Fijación Interna de Fracturas , Bloqueo Nervioso/métodos , Dolor Postoperatorio/prevención & control , Fracturas del Radio/cirugía , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Ultrasonografía Intervencional
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