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The choice to take-up specific complimentary and alternative medicine (CAM) modalities is influenced by many factors including cultural background, experience and peer-participation. In this study we investigated the beliefs and attitudes that contributed to CAM choices in a non-urban Malaysian population (N = 700). We found significant differences in the beliefs held by men and women in this population. Specifically, women believed more strongly than men that CAM providers offered healthy lifestyle advice (p = 0.042) and that those who were averse to discomfort from conventional treatments were more likely to take up CAM (p = 0.016). In addition, those individuals who chose to use CAM more strongly believed that CAM products were more healthy than conventional treatments (p = 0.002), that their effects were well understood (p = 0.002) and that CAM products worked with the body (p = 0.017). The data obtained in this study emphasize the lessons that can be learned by conventional healthcare providers in communicating the benefits of treatments to their patients. CAM users also believed that CAM products never caused harm (p = 0.007), which is a concern given that the modes of action of some CAM modalities and their interaction with prescribed treatments are not always well understood.
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Terapias Complementarias , Conocimientos, Actitudes y Práctica en Salud , Femenino , Personal de Salud , Humanos , Masculino , Grupo Paritario , Factores SexualesRESUMEN
Complementary and alternative medicine (CAM) therapies have been an integral part of Malaysia culture for many centuries. In recent years influences from other parts of the world have gained a foot-hold in Malaysian popular culture. We investigated the engagement with CAM in a non-urban, Malaysian population. We investigated the association of CAM use with cultural influence, perceived health status, gender and age. We recruited 700 adult participants to this study across three sites in central Malaysia. We found massage, Vitamin supplements, Herbal medicine and traditional Chinese medicine to be the most popular CAM modalities with participation at 67.7%, 55.7%, 55.5% and 26.3% respectively. CAM use was equally high at 67% among those people who claimed a predominantly Malay or Chinese cultural influence. The use of vitamins and participation in yoga were at higher prevalence among female participants compared to males. There was no gender difference for other CAM modalities. There were differences between age groups for most CAM modalities, and those over 50 years tended to be the highest frequency users for most modalities. There is a high rate of CAM use in non-urban Malaysia with younger people being more engaged with less traditional modalities such as aromatherapy, yoga and music therapy.
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Terapias Complementarias , Adulto , Estudios Transversales , Femenino , Medicina de Hierbas , Humanos , Masculino , Persona de Mediana Edad , Fitoterapia , PrevalenciaRESUMEN
The K+ channel KCNQ1 has been proposed as a tumor suppressor in colorectal cancer (CRC). We investigated the molecular mechanisms regulating KCNQ1:ß-catenin bidirectional interactions and their effects on CRC differentiation, proliferation, and invasion. Molecular and pharmacologic approaches were used to determine the influence of KCNQ1 expression on the Wnt/ß-catenin signaling and epithelial-to-mesenchymal transition (EMT) in human CRC cell lines of varying stages of differentiation. The expression of KCNQ1 was lost with increasing mesenchymal phenotype in poorly differentiated CRC cell lines as a consequence of repression of the KCNQ1 promoter by ß-catenin:T-cell factor (TCF)-4. In well-differentiated epithelial CRC cell lines, KCNQ1 was localized to the plasma membrane in a complex with ß-catenin and E-cadherin. The colocalization of KCNQ1 with adherens junction proteins was lost with increasing EMT phenotype. ShRNA knock-down of KCNQ1 caused a relocalization of ß-catenin from the plasma membrane and a loss of epithelial phenotype in CRC spheroids. Overexpression of KCNQ1 trapped ß-catenin at the plasma membrane, induced a patent lumen in CRC spheroids, and slowed CRC cell invasion. The KCNQ1 ion channel inhibitor chromanol 293B caused membrane depolarization, redistribution of ß-catenin into the cytosol, and a reduced transepithelial electrical resistance, and stimulated CRC cell proliferation. Analysis of human primary CRC tumor patient databases showed a positive correlation between KCNQ1:KCNE3 channel complex expression and disease-free survival. We conclude that the KCNQ1 ion channel is a target gene and regulator of the Wnt/ß-catenin pathway, and its repression leads to CRC cell proliferation, EMT, and tumorigenesis.
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Diferenciación Celular , Movimiento Celular , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/patología , Regulación Neoplásica de la Expresión Génica , Canal de Potasio KCNQ1/metabolismo , beta Catenina/metabolismo , Animales , Apoptosis , Carcinogénesis , Proliferación Celular , Neoplasias Colorrectales/genética , Transición Epitelial-Mesenquimal , Humanos , Canal de Potasio KCNQ1/genética , Masculino , Invasividad Neoplásica , Pronóstico , Regiones Promotoras Genéticas , Ratas Sprague-Dawley , Tasa de Supervivencia , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto , beta Catenina/genéticaRESUMEN
The Royal College of Surgeons in Ireland (RCSI) was among the first medical institutions to establish a global education community which now provides high-quality transnational health professions education aligned across three locations: Europe, the Middle East and South-East Asia. The successful implementation of a shared modularized curriculum in this context can be complex and challenging. Here we describe our insights, gained from a decade of working together as shared module Academic Leads to deliver a system-based medical module to an international student cohort. The themes covered are some of the areas where we consider our joint deliberations have led to improved outcomes for the delivery and assessment of the module, which may be helpful to academic staff embarking on similar module sharing experiences.
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Educación de Pregrado en Medicina/métodos , Cooperación Internacional , Asia , Curriculum , Educación de Pregrado en Medicina/normas , Humanos , Irlanda , Malasia , Medio Oriente , Estudiantes de MedicinaRESUMEN
Colorectal cancer (CRC) is one of the most common malignancies. In recent decades, early diagnosis and conventional therapies have resulted in a significant reduction in mortality. However, late stage metastatic disease still has very limited effective treatment options. There is a growing interest in using viruses to help target therapies to tumour sites. In recent years the evolution of immunotherapy has emphasised the importance of directing the immune system to eliminate tumour cells; we aim to give a state-of-the-art over-view of the diverse viruses that have been investigated as potential oncolytic agents for the treatment of CRC.
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Neoplasias del Colon/terapia , Viroterapia Oncolítica/tendencias , Virus Oncolíticos/patogenicidad , Neoplasias del Recto/terapia , Animales , Neoplasias del Colon/mortalidad , Neoplasias del Colon/patología , Neoplasias del Colon/virología , Difusión de Innovaciones , Predicción , Interacciones Huésped-Patógeno , Humanos , Viroterapia Oncolítica/efectos adversos , Neoplasias del Recto/mortalidad , Neoplasias del Recto/patología , Neoplasias del Recto/virología , Resultado del TratamientoRESUMEN
In addition to regulating B cell development and activation, Bruton's tyrosine kinase (Btk) functions downstream of multiple TLRs, including TLR7, to regulate innate immune responses in myeloid cells. Although critical for defense against RNA viruses such as influenza and Sendai virus, recognition of self-RNA by TLR7 also has been shown to be an important contributor to the pathophysiology of systemic lupus erythematosus. To date, the role of Btk in regulating TLR7-mediated responses is poorly understood. In the current study, we have demonstrated a hitherto undiscovered role for Btk in apoptotic cell uptake, identifying the molecular chaperone calreticulin (CRT) as a novel substrate for Btk in regulating this response. CRT together with the transmembrane receptor CD91 function at the cell membrane and regulate uptake of C1q-opsonised apoptotic cells. Our results show that Btk directly phosphorylates CRT and that in the absence of Btk, CRT fails to localize with CD91 at the cell surface and at the phagocytic cup. Critically, a blocking Ab against CRT in wild-type macrophages mimics the inability of Btk-deficient macrophages to phagocytose apoptotic cells efficiently, indicating the critical importance of Btk in regulating CRT-driven apoptotic cell uptake. Our data have revealed a novel regulatory role for Btk in mediating apoptotic cell clearance, with CRT identified as the critical component of the CRT/CD91/C1q system targeted by Btk. Given the importance of clearing apoptotic cell debris to prevent inappropriate exposure of TLRs to endogenous ligands, our results have important implications regarding the role of Btk in myeloid cell function.
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Apoptosis , Calreticulina/metabolismo , Complemento C1q/inmunología , Glicoproteínas de Membrana/metabolismo , Proteínas Tirosina Quinasas/metabolismo , Receptor Toll-Like 7/metabolismo , Agammaglobulinemia Tirosina Quinasa , Animales , Anticuerpos Bloqueadores/inmunología , Línea Celular , Membrana Celular/metabolismo , Proteína 1 Relacionada con Receptor de Lipoproteína de Baja Densidad , Activación de Linfocitos , Macrófagos/inmunología , Proteínas de la Membrana , Ratones , Células Mieloides/inmunología , Fagocitosis/inmunología , Fosforilación , Proteínas Tirosina Quinasas/genética , Proteínas Tirosina Quinasas/inmunología , Receptores de LDL/metabolismo , Transducción de Señal , Proteínas Supresoras de Tumor/metabolismoRESUMEN
The steroid hormone aldosterone is a key regulator of electrolyte transport in the kidney and contributes to both homeostatic whole-body electrolyte balance and the development of renal and cardiovascular pathologies. Aldosterone exerts its action principally through the mineralocorticoid receptor (MR), which acts as a ligand-dependent transcription factor in target tissues. Aldosterone also stimulates the activation of protein kinases and secondary messenger signaling cascades that act independently on specific molecular targets in the cell membrane and also modulate the transcriptional action of aldosterone through MR. This review describes current knowledge regarding the mechanisms and targets of rapid aldosterone action in the nephron and how aldosterone integrates these responses into the regulation of renal physiology.
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Aldosterona/fisiología , Riñón/fisiología , Receptores de Mineralocorticoides/fisiología , Animales , Transporte Biológico/fisiología , Canales Epiteliales de Sodio/fisiología , Humanos , Ratones , Proteínas Quinasas/fisiología , Ratas , Receptores de Factores de Crecimiento/fisiología , Transducción de Señal/fisiología , ATPasa Intercambiadora de Sodio-Potasio/fisiología , Transcripción Genética/fisiologíaRESUMEN
Hepatoblastoma is a rare liver cancer that occurs most often in children who present with lower birth weight. Cerebral palsy (CP) is a neurodevelopmental disorder distinguished by irregularities in muscle tone, movement, and motor skills. CP is caused by damage to the developing brain and is often associated with secondary complications such as severe constipation. Clinicians must be aware of sudden worsening constipation occurring in CP children because it can also be a sign of hepatoblastoma. The aim of this review is to summarize the current understanding of the risks for hepatoblastoma development in children with CP. Cancer risks likely include dysfunction of the immune system surveillance in CP children. Elevated C-reactive protein and tumor necrosis factor-alpha levels may be higher in children with CP, which weakens their innate immune system. Metabolic disruption increases the risk of some cancers, and poor nutrition and reduced growth that occur in CP patients may have an impact on cancer development through a loss in immune function. Increased mobility and physical activity can increase the T-cell, natural killer cell, and neutrophil population. Children with CP tend to engage poorly in physical activity, and consequently, their immune system is affected. There are multiple factors associated with CP that increase the risk of childhood cancers such as hepatoblastoma.
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Nephrotoxicity is a condition caused by toxic effects of medications and poisons resulting in the rapid decline of kidney function. Centella asiatica is a medicinal herb with antioxidative and anti-inflammatory characteristics that is used to treat a variety of ailments. The present study intends to explore the ability of Centella asiatica in preventing AlCl3 and D-Galactose-induced nephrotoxicity in rats. In this study 30 male albino Wistar rats were induced with nephrotoxicity using AlCl3 and D-galactose, and oral administration of Centella asiatica extract (100, 200, and 300mg/kg/day) was administered for 70 days. The kidneys were extracted after treatment and levels of oxidative and antioxidative enzymes, serum creatinine, and serum albumin were measured. The kidney's histopathological changes were studied. Administration of Centella asiatica extract significantly increased serum albumin, superoxide dismutase (SOD), and catalase levels in kidney homogenates while suppressing serum creatinine and malondialdehyde (MDA) levels and attenuating histopathological changes associated with nephrotoxicity. Centella asiatica extract lowered serum creatinine and oxidative stress levels in a drug-induced nephrotoxicity rat model, while simultaneously increasing serum albumin levels, as evidenced by mitigation of histological changes and normalisation of biomarkers of oxidative stress in the kidney.
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The kidney is considered to be one of the most estrogen-responsive, not reproductive organs in the body. Different estrogen receptors (ERs) show sex-specific differences in expression along the nephron and the expression of different ERs also changes with the estrous cycle of the female. The kidney becomes more estrogen-sensitive when estradiol levels are at their highest, just prior to ovulation. This review discusses the different mechanisms by which estradiol can modify the salt and water conservation processes of the kidney through transporter regulation to support the fluid and electrolyte homeostasis changes required in mammalian reproduction. The kidney plays a critical role in regulating blood pressure by controlling fluid homeostasis, and so protects the female cardiovascular system from dramatic changes in whole body fluid volume that occur at critical points in the human menstrual cycle and in pregnancy. This is augmented by the direct actions of estradiol on the cardiovascular system, for example through the direct stimulation of endothelial nitric oxide (NO) synthase, which releases NO to promote vasodilation. This and other mechanisms are less evident in the male and give women a degree of cardiovascular protection up until menopause, when the risks of cardiovascular disease and chronic kidney disease begin to match the risks experienced by males.
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Autoimmune diseases, such as systemic lupus erythematosus and rheumatoid arthritis, result from a loss of tolerance to self-antigens and immune-mediated injury precipitated by the overproduction of type I IFN and inflammatory cytokines. We have identified the inositol 5' phosphatase SHIP-1 as a negative regulator of TLR3-induced type I IFN production. SHIP-1-deficient macrophages display enhanced TLR-induced IFN-beta production, and overexpression of SHIP-1 negatively regulates the ability of TLR3 and its adaptor, Toll/IL-1 receptor domain-containing adaptor-inducing IFN-beta, to induce IFN-beta promoter activity, indicating that SHIP-1 negatively regulates TLR-induced IFN-beta production. Further dissection of the IFN-beta pathway implicates TANK-binding kinase 1 (TBK1) as the target for SHIP-1. Critically, in the absence of SHIP-1, TBK1 appears to be hyperphosphorylated both in unstimulated cells and following TLR3 stimulation. In addition, TBK1 appears to be constitutively associated with Toll/IL-1 receptor domain-containing adaptor-inducing IFN-beta and TNFR-associated factor 3 in SHIP-1 deficient cells, whereas in wild-type cells this association is inducible following TLR3 stimulation. In support of a role for SHIP-1 in regulating complex formation, confocal microscopy demonstrates that TBK1 distribution in the cell is significantly altered in SHIP-1-deficient cells, with more prominent endosomal staining observed, compared with wild-type controls. Taken together, our results point to SHIP-1 as a critical negative regulator of IFN-beta production downstream of TLR3 through the regulation of TBK1 localization and activity.
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Interferón beta/metabolismo , Monoéster Fosfórico Hidrolasas/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Receptor Toll-Like 3/metabolismo , Aminoquinolinas/farmacología , Animales , Western Blotting , Células de la Médula Ósea/citología , Células de la Médula Ósea/efectos de los fármacos , Células de la Médula Ósea/metabolismo , Línea Celular , Citocinas/metabolismo , Citometría de Flujo , Humanos , Imiquimod , Mediadores de Inflamación/metabolismo , Inositol Polifosfato 5-Fosfatasas , Interferón beta/genética , Lipopolisacáridos/farmacología , Macrófagos/citología , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Ratones , Ratones Noqueados , Microscopía Confocal , FN-kappa B/metabolismo , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatasas , Monoéster Fosfórico Hidrolasas/genética , Fosforilación , Regiones Promotoras Genéticas/genética , Unión Proteica , Proteínas Serina-Treonina Quinasas/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Receptor Toll-Like 3/genéticaRESUMEN
Many patients with Type 2 Diabetes (T2D) have difficulty in controlling their disease despite wide-spread availability of high-quality guidelines, T2D education programs and primary care follow-up programs. Current diabetes education and treatment programs translate knowledge from bench to bedside well, but underperform on the 'last-mile' of converting that knowledge into action (KTA). Two innovations to the last-mile problem in management of patients with T2D are introduced. 1) Design of a platform for peer-to-peer groups where patients can solve KTA problems together in a structured and psychologically safe environment using all the elements of the Action Cycle phase of the KTA framework. The platform uses Self-Determination Theory as the behavior change theory. 2) A novel patient segmentation method to enable the formation of groups of patients who have similar behavioral characteristics and therefore who are more likely to find common cause in the fight against diabetes.
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Diabetes Mellitus Tipo 2 , Diabetes Mellitus Tipo 2/terapia , Educación en Salud , Humanos , Conocimiento , Grupo ParitarioRESUMEN
The F(1)F(0)-ATP synthase provides approximately 90% of cardiac ATP, yet little is known regarding its regulation under normal or pathological conditions. Previously, we demonstrated that protein kinase Cdelta (PKCdelta) inhibits F(1)F(0) activity via an interaction with the "d" subunit of F(1)F(0)-ATP synthase (dF(1)F(0)) in neonatal cardiac myocytes (NCMs) (Nguyen, T., Ogbi, M., and Johnson, J. A. (2008) J. Biol. Chem. 283, 29831-29840). We have now identified a dF(1)F(0)-derived peptide (NH(2)-(2)AGRKLALKTIDWVSF(16)-COOH) that inhibits PKCdelta binding to dF(1)F(0) in overlay assays. We have also identified a second dF(1)F(0)-derived peptide (NH(2)-(111)RVREYEKQLEKIKNMI(126)-COOH) that facilitates PKCdelta binding to dF(1)F(0). Incubation of NCMs with versions of these peptides containing HIV-Tat protein transduction and mammalian mitochondrial targeting sequences resulted in their delivery into mitochondria. Preincubation of NCMs, with 10 nm extracellular concentrations of the mitochondrially targeted PKCdelta-dF(1)F(0) interaction inhibitor, decreased 100 nm 4beta-phorbol 12-myristate 13-acetate (4beta-PMA)-induced co-immunoprecipitation of PKCdelta with dF(1)F(0) by 50 +/- 15% and abolished the 30 nm 4beta-PMA-induced inhibition of F(1)F(0)-ATPase activity. A scrambled sequence (inactive) peptide, which contained HIV-Tat and mitochondrial targeting sequences, was without effect. In contrast, the cell-permeable, mitochondrially targeted PKCdelta-dF(1)F(0) facilitator peptide by itself induced the PKCdelta-dF(1)F(0) co-immunoprecipitation and inhibited F(1)F(0)-ATPase activity. In in vitro PKC add-back experiments, the PKCdelta-F(1)F(0) inhibitor blocked PKCdelta-mediated inhibition of F(1)F(0)-ATPase activity, whereas the facilitator induced inhibition. We have developed the first cell-permeable, mitochondrially targeted modulators of the PKCdelta-dF(1)F(0) interaction in NCMs. These novel peptides will improve our understanding of cardiac F(1)F(0) regulation and may have potential as therapeutics to attenuate cardiac injury.
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Permeabilidad de la Membrana Celular/efectos de los fármacos , Diseño de Fármacos , Mitocondrias/metabolismo , ATPasas de Translocación de Protón Mitocondriales/metabolismo , Miocitos Cardíacos/enzimología , Péptidos/farmacología , Proteína Quinasa C-delta/metabolismo , Secuencia de Aminoácidos , Animales , Animales Recién Nacidos , Pruebas de Enzimas , Inmunoprecipitación , Mitocondrias/efectos de los fármacos , ATPasas de Translocación de Protón Mitocondriales/antagonistas & inhibidores , ATPasas de Translocación de Protón Mitocondriales/química , Datos de Secuencia Molecular , Miocitos Cardíacos/efectos de los fármacos , Péptidos/síntesis química , Péptidos/química , Unión Proteica/efectos de los fármacos , Proteína Quinasa C-delta/química , Señales de Clasificación de Proteína , Subunidades de Proteína/antagonistas & inhibidores , Subunidades de Proteína/química , Subunidades de Proteína/metabolismo , Ratas , Ratas Sprague-Dawley , Acetato de Tetradecanoilforbol/farmacología , Productos del Gen tat del Virus de la Inmunodeficiencia Humana/farmacologíaRESUMEN
RATIONALE: An unexplained gender gap is observed in cystic fibrosis (CF). Females have poorer lung function, decreased survival, and earlier Pseudomonas colonization. OBJECTIVES: To evaluate the effect of 17beta-estradiol (E(2)) on CF bronchial epithelial cells in vitro and in vivo. METHODS: On exposure of CFBE41o- cultures to physiological concentrations of E(2), there was a significant dose-dependent inhibition of IL-8 release induced by toll-like receptor agonists, CF bronchoalveolar lavage fluid, or Pseudomonas-conditioned media. Estrogen receptor (ER)-alpha and -beta expression was quantified in cell lines and bronchial brushings from CF and non-CF patients. MEASUREMENTS AND MAIN RESULTS: Both receptors were expressed in vitro and in vivo, although ERbeta expression was significantly higher in CF. Using ER isoform-specific agonists and antagonists, we established that ERbeta mediates the inhibition of CF bronchoalveolar lavage fluid-induced IL-8 release. We also showed that secretory leucoprotease inhibitor gene expression and protein localization to the nucleus increased in response to E(2). Secretory leucoprotease inhibitor knockdown abrogated the inhibitory effects of E(2). CONCLUSIONS: E(2) inhibits IL-8 release by ERbeta in CF bronchial epithelial cells through up-regulation of secretory leucoprotease inhibitor, inhibition of nuclear factor (NF)-kappaB, and IL-8 gene expression. These data implicate a novel anti-inflammatory mechanism for E(2) in females with CF, which predisposes to infection and colonization. This could, in part, account for the observed gender dichotomy in CF.
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Fibrosis Quística/metabolismo , Células Epiteliales/metabolismo , Estradiol/fisiología , Interleucina-8/metabolismo , Inhibidor Secretorio de Peptidasas Leucocitarias/metabolismo , Adolescente , Adulto , Células Cultivadas , Receptor beta de Estrógeno/fisiología , Femenino , Humanos , Masculino , FN-kappa B/fisiología , Mucosa Respiratoria/metabolismo , Factores Sexuales , Regulación hacia Arriba , Adulto JovenRESUMEN
Lung cancer is increasing in incidence particularly among women, associated with a global change in smoking habits. Steroid hormones, particularly oestrogen exert an influence on tumour progression in tissues where their target receptor is expressed. Oestrogen receptor, particularly ERß is highly expressed in the lung and becomes more highly expressed in lung carcinogenesis. Genes involved in the process of lung carcinoma progression and signalling cascades linked to invasion and angiogenesis are modulated by oestrogen receptors. This review intends to collate recently published evidence identifying a role for oestrogen in the initiation and progression of lung carcinoma and how these two processes are differentially affected by circulating oestrogens both in women and in men. Circulating oestrogens may be a significant risk factor in women's susceptibility to lung carcinoma and also provide an additional approach for more targeted therapy.
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Carcinoma/sangre , Receptor alfa de Estrógeno/sangre , Receptor beta de Estrógeno/sangre , Estrógenos/sangre , Neoplasias Pulmonares/sangre , Carcinoma/epidemiología , Carcinoma/patología , Femenino , Humanos , Pulmón/patología , Neoplasias Pulmonares/epidemiología , Neoplasias Pulmonares/patología , Masculino , Factores de Riesgo , Caracteres Sexuales , Transducción de Señal/genética , Fumar/efectos adversosRESUMEN
Protein kinase D2 (PKD2) is a serine/threonine protein kinase which plays an important role in vesicle fission at the trans-Golgi network (TGN) to coordinate subcellular trafficking with gene expression. We found that in the rat kidney, PKD2 is specifically expressed in collecting duct principal cells predominantly at the apical membrane and with lower basal expression in cytosolic compartments. When rats were maintained on a Na+ depleted diet (<0.87 mmol Na+/kg) to increase plasma aldosterone levels, PKD2 became internalized to a cytoplasmic compartment. Treatment of murine M1 cortical collecting duct (M1-CCD) cells with aldosterone (10 nM) promoted PKD2 co-localization with the trans-Golgi network within 30 min. PKD2 underwent autophosphorylation at Ser876 within 10 min of aldosterone treatment and remained phosphorylated (active) for at least 24 h. A stable PKD2 shRNA knock-down (PKD2 KD) M1-CCD cell line was developed to study the role of PKD2 in epithelial Na+ channel (ENaC) trafficking and transepithelial Na+ transport (SCC) in epithelial monolayers grown in Ussing chambers. The PKD2 KD cells developed transepithelial resistance with kinetics equivalent to wild-type cells, however the transepithelial voltage and Na+ current were significantly elevated in PKD2 knock-down CCD epithelia. The higher basal SCC was due to increased ENaC activity. Aldosterone treatment for 24 h resulted in a decline in ENaC activity in the PKD2 KD cells as opposed to the increase observed in the wild-type cells. The paradoxical inhibition of SCC by aldosterone in PKD2 KD epithelium was attributed to a reduction in ENaC current and lower membrane abundance of ENaC, demonstrating that PKD2 plays a critical tonic role in ENaC trafficking and channel subunit stability. The rapid activation of PKD2 by aldosterone is synergistic with the transcriptional activity of MR and contributes to increased ENaC activity.
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Aldosterona/farmacología , Canales Epiteliales de Sodio/metabolismo , Túbulos Renales Colectores/efectos de los fármacos , Proteínas Quinasas/metabolismo , Aldosterona/sangre , Animales , Células Cultivadas , Modelos Animales de Enfermedad , Túbulos Renales Colectores/metabolismo , Masculino , Ratones , Ratones Transgénicos , Fosforilación , Proteína Quinasa D2 , Inhibidores de Proteínas Quinasas/farmacología , ARN Interferente Pequeño/farmacología , Ratas , Ratas Sprague-DawleyRESUMEN
Antimicrobials are useful compounds intended to eradicate or stop the growth of harmful microorganisms. The sustained increase in the rates of antimicrobial resistance (AMR) worldwide is worrying and poses a major public health threat. The development of new antimicrobial agents is one of the critical approaches to overcome AMR. However, in the race towards developing alternative approaches to combat AMR, it appears that the scientific community is falling behind when pitched against the evolutionary capacity of multi-drug resistant (MDR) bacteria. Although the "pioneering strategy" of discovering completely new drugs is a rational approach, the time and effort taken are considerable, the process of drug development could instead be expedited if efforts were concentrated on enhancing the efficacy of existing antimicrobials through: combination therapies; bacteriophage therapy; antimicrobial adjuvants therapy or the application of nanotechnology. This review will briefly detail the causes and mechanisms of AMR as background, and then provide insights into a novel, future emerging or evolving strategies that are currently being evaluated and which may be developed in the future to tackle the progression of AMR.
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Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Infecciones Bacterianas/terapia , Farmacorresistencia Bacteriana Múltiple/fisiología , Terapia de Fagos/métodos , Antibacterianos/uso terapéutico , Bacterias/virología , Infecciones Bacterianas/microbiología , Proteínas Bacterianas/antagonistas & inhibidores , Proteínas Bacterianas/metabolismo , Biopelículas/efectos de los fármacos , Terapia Combinada/métodos , Portadores de Fármacos/química , Descubrimiento de Drogas , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Quimioterapia Combinada/métodos , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/uso terapéutico , Humanos , Nanopartículas/químicaRESUMEN
Misuse of antibiotics in the clinical and agricultural sectors has caused the emergence of multidrug-resistant (MDR) Klebsiella pneumoniae which contributes a threat to human health. In this study, we assessed the feasibility of lavender essential oil (LVO) as an antimicrobial agent in combinatory therapy with meropenem in suppressing the growth of carbapenemase-producing K. pneumoniae (KPC-KP). Synergistic interactions between LVO and meropenem were detected, which significantly reduce the inhibitory concentration of both LVO and meropenem by 15 and 4-fold respectively. Comparative proteomic profiling identified a disruption in the bacterial membrane via oxidative stress that was indicated by loss of membrane and cytoplasmic proteins and the upregulation of oxidative regulators. As a proof of concept, zeta potential measurements showed a change in cell surface charge while outer membrane permeability measurement indicated an increase in membrane permeability following exposure to LVO. This was indicative of a disrupted outer membrane. Ethidium bromide influx/efflux assays demonstrated no significant efflux pump inhibition by LVO, and scanning electron microscopy revealed irregularities on the cell surface after exposure to LVO. Oxidative stress was also detected with increased level of ROS and lipid peroxidation in LVO-treated cells. In conclusion, our data suggest that LVO induced oxidative stress in K. pneumoniae which oxidizes the outer membrane, enabling the influx of generated ROS, LVO and meropenem into the bacterial cells, causing damage to the cells and eventually death.
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Antibacterianos , Permeabilidad de la Membrana Celular/efectos de los fármacos , Klebsiella pneumoniae/efectos de los fármacos , Aceites Volátiles/farmacología , Estrés Oxidativo/efectos de los fármacos , Aceites de Plantas/farmacología , Proteínas Bacterianas/metabolismo , Farmacorresistencia Bacteriana , Sinergismo Farmacológico , Estudios de Factibilidad , Klebsiella pneumoniae/citología , Klebsiella pneumoniae/crecimiento & desarrollo , Klebsiella pneumoniae/metabolismo , Lavandula , Meropenem/farmacología , Pruebas de Sensibilidad Microbiana , Especies Reactivas de Oxígeno/metabolismo , beta-Lactamasas/metabolismoRESUMEN
The intestine is an oestrogen responsive organ and circulatory oestrogens suppress Cl(-) secretion across the epithelium of the colon to promote fluid retention at the luteal stage of the menstrual cycle. Ion transporters in the colon which are involved in Cl(-) secretion show differential expression between males and females as do the signalling protein kinase intermediates involved in acutely regulating these transporters. Work from our laboratory has identified the KCNQ1/KCNE3 channel as one of the principal targets for oestrogen-induced signalling cascades in the distal colon. Through inhibition of the KCNQ1 channel, basolateral K(+) recycling is decreased so reducing the favourable electrochemical gradient for Cl(-) extrusion at the apical membrane. The actions of oestrogen on non-reproductive tissues such as the colon, kidney, lung and sweat gland will affect whole body electrolyte and fluid homeostasis and also have consequences for reproductive potential.
Asunto(s)
Cloro/metabolismo , Estrógenos/metabolismo , Intestinos/fisiología , Canales Iónicos/fisiología , Ciclo Menstrual/fisiología , Potasio/metabolismo , Transducción de Señal/fisiología , Animales , Femenino , Humanos , Factores SexualesRESUMEN
Aldosterone elicits rapid physiological responses in target tissues such as the distal nephron through the stimulation of cell signaling cascades. We identified protein kinase D (PKD1) as an early signaling response to aldosterone treatment in the M1-cortical collecting duct (M1-CCD) cell line. PKD1 activation was blocked by the PKC inhibitor chelerythrine chloride and by rottlerin, a specific inhibitor of PKCdelta. The activation of PKCdelta and PKCepsilon coincided with PKD1 activation and while a complex was formed between PKD1 and PKCepsilon after aldosterone treatment, there was a concurrent reduction in PKD1 association with PKCdelta. A stable PKD1 knockdown M1-CCD-derrived clone was developed in which PKD1 expression was 90% suppressed by gene silencing with a PKD1-specific siRNA. The effect of aldosterone treatment on the subcellular distribution of enhanced cyan fluorescent protein (eCFP)-tagged epithelial sodium channel (ENaC) subunits in wild type (WT) and PKD1 suppressed cells was examined using confocal microscopy. In an untreated confluent monolayer of M1-CCD cells, alpha, beta, and gamma ENaC subunits were evenly distributed throughout the cytoplasm of WT and PKD1-suppressed cells. After 2 min treatment, aldosterone stimulated the localization of each of the ENaC subunits to discrete regions within the cytoplasm of WT cells. The translocation of eCFP-ENaC subunits in WT cells was inhibited by rottlerin and the mineralocorticoid receptor (MR) antagonist spironolactone. No subcellular translocation of eCFP-ENaC subunits was observed in PKD1-suppressed cells treated with aldosterone. These data demonstrate the involvement of a novel MR/PKCdelta /PKD1 signaling cascade in the earliest ENaC subunit intracellular trafficking events that follow aldosterone treatment.