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BACKGROUND: Intravenous thrombolysis is contraindicated in patients with ischaemic stroke with blood pressure higher than 185/110 mm Hg. Prevailing guidelines recommend to actively lower blood pressure with intravenous antihypertensive agents to allow for thrombolysis; however, there is no robust evidence for this strategy. Because rapid declines in blood pressure can also adversely affect clinical outcomes, several Dutch stroke centres use a conservative strategy that does not involve the reduction of blood pressure. We aimed to compare the clinical outcomes of both strategies. METHODS: Thrombolysis and Uncontrolled Hypertension (TRUTH) was a prospective, observational, cluster-based, parallel-group study conducted across 37 stroke centres in the Netherlands. Participating centres had to strictly adhere to an active blood-pressure-lowering strategy or to a non-lowering strategy. Eligible participants were adults (≥18 years) with ischaemic stroke who had blood pressure higher than 185/110 mm Hg but were otherwise eligible for intravenous thrombolysis. The primary outcome was functional status at 90 days, measured using the modified Rankin Scale and assessed through telephone interviews by trained research nurses. Secondary outcomes were symptomatic intracranial haemorrhage, the proportion of patients treated with intravenous thrombolysis, and door-to-needle time. All ordinal logistic regression analyses were adjusted for age, sex, stroke severity, endovascular thrombectomy, and baseline imbalances as fixed-effect variables and centre as a random-effect variable to account for the clustered design. Analyses were done according to the intention-to-treat principle, whereby all patients were analysed according to the treatment strategy of the participating centre at which they were treated. FINDINGS: Recruitment began on Jan 1, 2015, and was prematurely halted because of a declining inclusion rate and insufficient funding on Jan 5, 2022. Between these dates, we recruited 853 patients from 27 centres that followed an active blood-pressure-lowering strategy and 199 patients from ten centres that followed a non-lowering strategy. Baseline characteristics of participants from the two groups were similar. The 90-day mRS score was missing for 15 patients. The adjusted odds ratio (aOR) for a shift towards a worse 90-day functional outcome was 1·27 (95% CI 0·96-1·68) for active blood-pressure reduction compared with no active blood-pressure reduction. 798 (94%) of 853 patients in the active blood-pressure-lowering group were treated with intravenous thrombolysis, with a median door-to-needle time of 35 min (IQR 25-52), compared with 104 (52%) of 199 patients treated in the non-lowering group with a median time of 47 min (29-78). 42 (5%) of 852 patients in the active blood-pressure-lowering group had a symptomatic intracranial haemorrhage compared with six (3%) of 199 of those in the non-lowering group (aOR 1·28 [95% CI 0·62-2·62]). INTERPRETATION: Insufficient evidence was available to establish a difference between an active blood-pressure-lowering strategy-in which antihypertensive agents were administered to reduce blood pressure below 185/110 mm Hg-and a non-lowering strategy for the functional outcomes of patients with ischaemic stroke, despite higher intravenous thrombolysis rates and shorter door-to-needle times among those in the active blood-pressure-lowering group. Randomised controlled trials are needed to inform the use of an active blood-pressure-lowering strategy. FUNDING: Fonds NutsOhra.
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Antihipertensivos , Accidente Cerebrovascular Isquémico , Terapia Trombolítica , Humanos , Femenino , Masculino , Países Bajos , Anciano , Accidente Cerebrovascular Isquémico/tratamiento farmacológico , Accidente Cerebrovascular Isquémico/terapia , Terapia Trombolítica/métodos , Persona de Mediana Edad , Estudios Prospectivos , Antihipertensivos/uso terapéutico , Antihipertensivos/administración & dosificación , Hipertensión/tratamiento farmacológico , Fibrinolíticos/administración & dosificación , Fibrinolíticos/uso terapéutico , Resultado del Tratamiento , Anciano de 80 o más Años , Presión Sanguínea/fisiología , Presión Sanguínea/efectos de los fármacosRESUMEN
BACKGROUND: Guidelines recommend routine transthoracic echocardiography (TTE) after ischaemic stroke or transient ischaemic attack of undetermined cause; yet, only limited scientific evidence exists. Therefore, we aimed to determine in these patients the prevalence of TTE-detected major cardiac sources of embolism (CSE), which are abnormalities leading to therapeutic changes. METHODS: Six Dutch hospitals conducted a prospective observational study that enrolled patients with ischaemic stroke or transient ischaemic attack of undetermined cause. Patients underwent TTE after comprehensive diagnostic evaluation on stroke units, including blood chemistry, 12-lead electrocardiogram (ECG), ≥â¯24â¯h continuous ECG monitoring, brain imaging and cervical artery imaging. Primary outcome measure was the proportion of patients with TTE-detected major CSE. RESULTS: From March 2018 to October 2020, 1084 patients, aged 66.6⯱ 12.5 years, were enrolled; 456 (42.1%) patients were female and 869 (80.2%) had ischaemic stroke. TTE detected major CSE in only 11 (1.0%) patients. Ten (90.9%) of these patients also had major ECG abnormalities (previous infarction, major repolarisation abnormalities, or previously unknown left bundle branch block) that would have warranted TTE assessment regardless of stroke evaluation. Such ECG abnormalities were present in 11.1% of the total study population. A single patient (0.1%) showed a major CSE despite having no ECG abnormality. CONCLUSIONS: This multicentre cross-sectional study in patients who-after workup on contemporary stroke units-were diagnosed with ischaemic stroke or transient ischaemic attack of undetermined cause found TTE-detected major CSE in only 1% of all patients. Most of these patients also had major ECG abnormalities. These findings question the value of routine TTE assessment in this clinical setting.
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OBJECTIVE: To compare experts' perceived usefulness of audit filters from Ghana, Cameroon, WHO and those locally developed; generate context-appropriate audit filters for trauma care in selected hospitals in urban India; and explore characteristics of audit filters that correlate to perceived usefulness. DESIGN: A mixed-methods approach using a multicentre online Delphi technique. SETTING: Two large tertiary hospitals in urban India. METHODS: Filters were rated on a scale from 1 to 10 in terms of perceived usefulness, with the option to add new filters and comments. The filters were categorised into three groups depending on their origin: low and middle-income countries (LMIC), WHO and New (locally developed), and their scores compared. Significance was determined using Kruskal-Wallis test followed by Wilcoxon rank-sum test. We performed a content analysis of the comments. RESULTS: 26 predefined and 15 new filter suggestions were evaluated. The filters had high usefulness scores (mean overall score 9.01 of 10), with the LMIC filters having significantly higher scores compared with those from WHO and those newly added. Three themes were identified in the content analysis relating to medical relevance, feasibility and specificity. CONCLUSIONS: Audit filters from other LMICs were deemed highly useful in the urban India context. This may indicate that the transferability of defined trauma audit filters between similar contexts is high and that these can provide a starting point when implemented as part of trauma quality improvement programmes in low-resource settings.
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Países en Desarrollo , Heridas y Lesiones , Técnica Delphi , Humanos , Auditoría Médica/métodos , Mejoramiento de la Calidad , Organización Mundial de la Salud , Heridas y Lesiones/terapiaRESUMEN
Background: Antibody testing is often used for serosurveillance of coronavirus disease 2019 (COVID-19). Enzyme-linked immunosorbent assay and chemiluminescence-based antibody tests are quite sensitive and specific for such serological testing. Rapid antibody tests against different antigens are developed and effectively used for this purpose. However, their diagnostic efficiency, especially in real-life hospital setting, needs to be evaluated. Thus, the present study was conducted in a dedicated COVID-19 hospital in New Delhi, India, to evaluate the diagnostic efficacy of a rapid antibody kit against the receptor-binding domain (RBD) of the spike protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Methods: Sixty COVID-19 confirmed cases by reverse transcriptase-polymerase chain reaction (RT-PCR) were recruited and categorized as early, intermediate, and late cases based on the days passed after their first RT-PCR-positive test report, with 20 subjects in each category. Twenty samples from pre-COVID era and 20 RT-PCR-negative collected during the study period were taken as controls. immunoglobulin M (IgM) and immunoglobulin G (IgG) antibodies against the RBD of the spike (S) protein of SARS-CoV-2 virus were detected by rapid antibody test and compared with the total antibody against the nucleocapsid (N) antigen of SARS-CoV-2 by electrochemiluminescence-based immunoassay (ECLIA). Results: The detection of IgM against the RBD of the spike protein by rapid kit was less sensitive and less specific for the diagnosis of SARS-CoV-2 infection. However, diagnostic efficacy of IgG by rapid kit was highly sensitive and specific when compared with the total antibody against N antigen measured by ECLIA. Conclusion: It can be concluded that detection of IgM against the RBD of S protein by rapid kit is less effective, but IgG detection can be used as an effective diagnostic tool for SARS-CoV-2 infection in real-life hospital setting.
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The synergy between the genetic potential and the nutrient intake determines the growth performance of meat-type chicken and nutrigenomics approach helps us understand the response of candidate genes of growth in chicken to dietary manipulations. The current study aimed to assess the growth performance and expression of hepatic growth related genes in the naked neck broiler chicken in response to different dietary energy and protein levels with a hypothesis that high plane of nutrition enhances both of these positively. The results revealed that birds have shown significantly better growth performance under high protein (HP) and high energy (HE) dietary regime. The expression profiles of the genes studied revealed upregulation of IGF-1, IGF-2, and GH under dietary HP and HE regime relative to other protein and energy levels with greater upregulation at 3rd week than the 1st and 5th week of age of birds. The IGFR and GHR mRNA expression was significantly higher under HP and HE dietary regimen with an increasing and decreasing trend from 1st to 5th week of age, respectively. A consistent and significant downregulation of IGFBP-2 was observed under HP and HE regime throughout the feeding trial. The myostatin expression was higher at 3rd week of age followed by 1st week expression. The HP and HE as well as LP (Low protein) and HE diet resulted in significant upregulation of myostatin gene expression in liver. In support to the set hypothesis of this study the high protein and high energy diet resulted in better growth performance of broiler chickens with corresponding upregulation of IGF-1, IGF-2, IGFR, GH, GHR, and Myostatin gene expression and downregulation of IGFBP-2 in liver.
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Pollos/crecimiento & desarrollo , Pollos/genética , Dieta , Proteínas en la Dieta/administración & dosificación , Metabolismo Energético/efectos de los fármacos , Alimentación Animal , Fenómenos Fisiológicos Nutricionales de los Animales/genética , Animales , Pollos/metabolismo , Proteínas en la Dieta/farmacología , Ingestión de Energía/efectos de los fármacos , Metabolismo Energético/genética , Femenino , Expresión Génica/efectos de los fármacos , Hormona del Crecimiento/genética , Hormona del Crecimiento/metabolismo , Proteína 2 de Unión a Factor de Crecimiento Similar a la Insulina/genética , Proteína 2 de Unión a Factor de Crecimiento Similar a la Insulina/metabolismo , Factor I del Crecimiento Similar a la Insulina/genética , Factor I del Crecimiento Similar a la Insulina/metabolismo , Factor II del Crecimiento Similar a la Insulina/genética , Factor II del Crecimiento Similar a la Insulina/metabolismo , Masculino , Distribución Aleatoria , Receptor IGF Tipo 1/genética , Receptor IGF Tipo 1/metabolismoRESUMEN
Several exported Plasmodium falciparum (Pf) proteins contribute to malaria biology through their involvement in cytoadherence, immune evasion and host cell remodelling. Many of these exported proteins and other host molecules are present in iRBC (infected red blood cell) generated extracellular vesicles (EVs), which are responsible for host cell modification and parasite development. CX3CL1 binding proteins (CBPs) present on the surface of iRBCs have been reported to contribute to cytoadhesion by binding with the chemokine 'CX3CL1' via their extracellular domains. Here, we have characterized the cytoplasmic domain of CBP2 to understand its function in parasite biology using biochemical and biophysical methods. Recombinant cytoplasmic CBP2 (cCBP2) binds nucleic acids showing interaction with DNA/RNA. cCBP2 shows dimer formation under non-reducing conditions highlighting the role of disulphide bonds in its oligomerization while ATP binding leads to structural changes in the protein. In vitro interaction studies depict its binding with a Maurer's cleft resident protein 'PfSBP1', which is influenced by ATP binding of cCBP2. Our results suggest CBP2 as a two-transmembrane (2TM) receptor responsible for targeting EVs and delivering cargo to host endothelial cells. We propose CBP2 as an important molecule having roles in cytoadherence and immune modulation through its extracellular and cytoplasmic domains respectively.
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Quimiocina CX3CL1/metabolismo , Ácidos Nucleicos/metabolismo , Plasmodium falciparum/metabolismo , Proteínas Protozoarias/metabolismo , Adenosina Trifosfato/metabolismo , Secuencia de Aminoácidos , Quimiocina CX3CL1/química , Humanos , Malaria Falciparum/metabolismo , Malaria Falciparum/parasitología , Modelos Biológicos , Modelos Moleculares , Unión Proteica , Conformación Proteica , Dominios y Motivos de Interacción de Proteínas , Proteínas Protozoarias/químicaRESUMEN
Sex steroid hormones play an important role in reproductive tissue development of avian species. However, their role in Japanese quail is yet to be established. To understand the physiological role of hormones involved in the development of sperm storage tubules (SSTs) in quail, we investigated expression profiles of gonadotropin (LH-R and FSH-R) and sex steroid hormone (PR-R, ER-α and ER-ß) receptors in the uterovaginal junction (UVJ) containing SSTs before and during sexual maturation i.e. four to eight weeks. Every week four birds were sacrificed to collect blood and UVJ for sex steroid hormone (progesterone and estrogen) estimation and gene expression profiling of sex steroid hormone (PR-R, ER-α and ER-ß) and gonadotropin receptors (LH-R and FSH-R) using qRT-PCR. Receptor expression results showed that the expression of sex steroid receptor (PR-R, ER-α and ER-ß) genes were upregulated significantly (Pâ¯<â¯.05) in SSTs with the advancement of age. The expression of gonadotropin receptors (LH-R and FSH-R) was only high at week 5 and 6 respectively. Serum hormone analysis indicated a significant (Pâ¯<â¯.05) rise in estradiol till 7thâ¯week and progesterone from 7thâ¯week onwards. These results suggest that the gonadotropin and sex steroid hormone receptors may have the role in the development and maintenance of UVJ that contains predominantly SSTs during sexual maturation.
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Coturnix , Hormonas Esteroides Gonadales/metabolismo , Gonadotropinas/metabolismo , Oviductos/metabolismo , ARN Mensajero/metabolismo , Maduración Sexual/fisiología , Útero/metabolismo , Vagina/metabolismo , Animales , FemeninoRESUMEN
BACKGROUND AND PURPOSE: Subfebrile body temperature and fever in the first days after stroke are strongly associated with unfavorable outcome. A subgroup analysis of a previous trial suggested that early treatment with paracetamol may improve functional outcome in patients with acute stroke and a body temperature of ≥36.5°C. In the present trial, we aimed to confirm this finding. METHODS: PAIS 2 (Paracetamol [Acetaminophen] in Stroke 2) was a multicenter, randomized, double-blind, placebo-controlled clinical trial. We aimed to include 1500 patients with acute ischemic stroke or intracerebral hemorrhage within 12 hours of symptom onset. Patients were treated with paracetamol in a daily dose of 6 g or matching placebo for 3 consecutive days. The primary outcome was functional outcome at 3 months, assessed with the modified Rankin Scale and analyzed with multivariable ordinal logistic regression. Because of slow recruitment and lack of funding, the study was stopped prematurely. RESULTS: Between December 2011 and October 2015, we included 256 patients, of whom 136 (53%) were allocated to paracetamol. In this small sample, paracetamol had no effect on functional outcome (adjusted common odds ratio, 1.15; 95% confidence interval, 0.74-1.79). There was no difference in the number of serious adverse events (paracetamol n=35 [26%] versus placebo n=28 [24%]). CONCLUSIONS: Treatment with high-dose paracetamol seemed to be safe. The effect of high-dose paracetamol on functional outcome remains uncertain. Therefore, a large trial of early treatment with high-dose paracetamol is still needed. CLINICAL TRIAL REGISTRATION: URL: http://www.trialregister.nl. Unique identifier: NTR2365.
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Acetaminofén/farmacología , Antipiréticos/farmacología , Isquemia Encefálica/complicaciones , Hemorragia Cerebral/complicaciones , Fiebre/tratamiento farmacológico , Evaluación de Resultado en la Atención de Salud , Accidente Cerebrovascular/tratamiento farmacológico , Acetaminofén/administración & dosificación , Anciano , Anciano de 80 o más Años , Antipiréticos/administración & dosificación , Método Doble Ciego , Femenino , Fiebre/etiología , Humanos , Masculino , Persona de Mediana Edad , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/etiologíaRESUMEN
RATIONALE: In the first hours after stroke onset, subfebrile temperatures and fever have been associated with poor functional outcome. In the first Paracetamol (Acetaminophen) in Stroke trial, a randomized clinical trial of 1400 patients with acute stroke, patients who were treated with high-dose paracetamol showed more improvement on the modified Rankin Scale at three-months than patients treated with placebo, but this difference was not statistically significant. In the 661 patients with a baseline body temperature of 37.0 °C or above, treatment with paracetamol increased the odds of functional improvement (odds ratio 1.43; 95% confidence interval: 1.02-1.97). This relation was also found in the patients with a body temperature of 36.5 °C or higher (odds ratio 1.31; 95% confidence interval 1.01-1.68). These findings need confirmation. AIM: The study aims to assess the effect of high-dose paracetamol in patients with acute stroke and a body temperature of 36.5 °C or above on functional outcome. DESIGN: The Paracetamol (Acetaminophen) In Stroke 2 trial is a multicenter, randomized, double-blind, placebo-controlled clinical trial. We use a power of 85% to detect a significant difference in the scores on the modified Rankin Scale of the paracetamol group compared with the placebo group at a level of significance of 0.05 and assume a treatment effect of 7%. Fifteen-hundred patients with acute ischemic stroke or intracerebral hemorrhage and a body temperature of 36.5 °C or above will be included within 12 h of symptom onset. Patients will be treated with paracetamol in a daily dose of six-grams or matching placebo for three consecutive days. The Paracetamol (Acetaminophen) In Stroke 2 trial has been registered as NTR2365 in The Netherlands Trial Register. STUDY OUTCOMES: The primary outcome will be improvement on the modified Rankin Scale at three-months as analyzed by ordinal logistic regression. DISCUSSION: If high-dose paracetamol will be proven effective, a simple, safe, and extremely cheap therapy will be available for many patients with acute stroke worldwide.
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Acetaminofén/uso terapéutico , Antipiréticos/uso terapéutico , Fiebre/tratamiento farmacológico , Fiebre/etiología , Ensayos Clínicos Controlados Aleatorios como Asunto , Accidente Cerebrovascular/complicaciones , Temperatura Corporal/efectos de los fármacos , Protocolos Clínicos , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Humanos , Masculino , Estudios Multicéntricos como Asunto , Accidente Cerebrovascular/tratamiento farmacológicoRESUMEN
An increase in body temperature in the first days following stroke is related to poor functional outcome. High-dose paracetamol (acetaminophen) reduces the body temperature by 0.3°C and can prevent fever. Paracetamol treatment is simple, cheap and has few side effects. In the first "Paracetamol (Acetaminophen) in Stroke" (PAIS) study, there was a beneficial effect of high-dose paracetamol on functional outcome in patients with stroke and a body temperature of 37.0°C or above. Because this result was found in a subgroup analysis, a new study is needed to confirm this finding. Recently the randomised PAIS 2 study was initiated. This study aims to assess the effect of high-dose paracetamol on functional outcome in patients with acute stoke and a body temperature of 37.0°C or above.
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Acetaminofén/uso terapéutico , Antiinflamatorios no Esteroideos/uso terapéutico , Hipotermia Inducida , Acetaminofén/efectos adversos , Antiinflamatorios no Esteroideos/efectos adversos , Relación Dosis-Respuesta a Droga , Fiebre/prevención & control , Humanos , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/tratamiento farmacológico , Resultado del TratamientoRESUMEN
Mechanical forces are essential to maintain skeletal integrity, and microgravity exposure leads to bone loss. The underlying molecular mechanisms leading to the changes in osteoblasts and osteoclast differentiation and function remain to be fully elucidated. Because of the infrequency of spaceflights and payload constraints, establishing in vitro and in vivo systems that mimic microgravity conditions becomes necessary. We have established a simulated microgravity (modeled microgravity, MMG) system to study the changes induced in osteoclast precursors. We observed that MMG, on its own, was unable to induce osteoclastogenesis of osteoclast precursors; however, 24 h of MMG activates osteoclastogenesis-related signaling molecules ERK, p38, PLCγ2, and NFATc1. Receptor activator of NFkB ligand (RANKL) (with or without M-CSF) stimulation for 3-4 days in gravity of cells that had been exposed to MMG for 24 h enhanced the formation of very large tartrate-resistant acid phosphatase (TRAP)-positive multinucleated (>30 nuclei) osteoclasts accompanied by an upregulation of the osteoclast marker genes TRAP and cathepsin K. To validate the in vitro system, we studied the hindlimb unloading (HLU) system using BALB/c mice and observed a decrease in BMD of femurs and a loss of 3D microstructure of both cortical and trabecular bone as determined by micro-CT. There was a marked stimulation of osteoclastogenesis as determined by the total number of TRAP-positive multinucleated osteoclasts formed and also an increase in RANKL-stimulated osteoclastogenesis from precursors removed from the tibias of mice after 28 days of HLU. In contrast to earlier reported findings, we did not observe any histomorphometric changes in the bone formation parameters. Thus, the foregoing observations indicate that microgravity sensitizes osteoclast precursors for increased differentiation. The in vitro model system described here is potentially a valid system for testing drugs for preventing microgravity-induced bone loss by targeting the molecular events occurring in microgravity-induced enhanced osteoclastogenesis.
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Osteoclastos/citología , Ligando RANK/farmacología , Ingravidez , Fosfatasa Ácida/metabolismo , Animales , Apoptosis/efectos de los fármacos , Western Blotting , Densidad Ósea/efectos de los fármacos , Línea Celular , Suspensión Trasera/fisiología , Isoenzimas/metabolismo , Masculino , Ratones , Ratones Endogámicos BALB C , Osteoblastos/citología , Osteoblastos/efectos de los fármacos , Osteoclastos/efectos de los fármacos , Receptor Activador del Factor Nuclear kappa-B/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Fosfatasa Ácida TartratorresistenteRESUMEN
The BRMS1 metastasis suppressor interacts with the protein AT-rich interactive domain 4A (ARID4A, RBBP1) as part of SIN3.histone deacetylase chromatin remodeling complexes. These transcriptional co-repressors regulate diverse cell phenotypes depending upon complex composition. To define BRMS1 complexes and their roles in metastasis suppression, we generated BRMS1 mutants (BRMS1(mut)) and mapped ARID4A interactions. BRMS1(L174D) disrupted direct interaction with ARID4A in yeast two-hybrid genetic screens but retained an indirect association with ARID4A in MDA-MB-231 and -435 human breast cancer cell lines by co-immunoprecipitation. Deletion of the first coiled-coil domain (BRMS1(DeltaCC1)) did not disrupt direct interaction in yeast two-hybrid screens but did prevent association by co-immunoprecipitation. These results suggest altered complex composition with BRMS1(mut). Although basal transcription repression was impaired and the pro-metastatic protein osteopontin was differentially down-regulated by BRMS1(L174D) and BRMS1(DeltaCC1), both down-regulated the epidermal growth factor receptor and suppressed metastasis in MDA-MB-231 and -435 breast cancer xenograft models. We conclude that BRMS1(mut), which modifies the composition of a SIN3.histone deacetylase chromatin remodeling complex, leads to altered gene expression profiles. Because metastasis requires the coordinate expression of multiple genes, down-regulation of at least one important gene, such as the epidermal growth factor receptor, had the ability to suppress metastasis. Understanding which interactions are necessary for particular biochemical/cellular functions may prove important for future strategies targeting metastasis.
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Neoplasias de la Mama/metabolismo , Proteínas Portadoras/metabolismo , Ensamble y Desensamble de Cromatina , Regulación Neoplásica de la Expresión Génica , Histona Desacetilasas/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas Represoras/metabolismo , Animales , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Proteínas Portadoras/genética , Línea Celular Tumoral , Ensamble y Desensamble de Cromatina/genética , Regulación hacia Abajo/genética , Receptores ErbB/biosíntesis , Receptores ErbB/genética , Femenino , Regulación Neoplásica de la Expresión Génica/genética , Histona Desacetilasas/genética , Humanos , Ratones , Mutación , Metástasis de la Neoplasia , Proteínas de Neoplasias/genética , Trasplante de Neoplasias , Osteopontina/biosíntesis , Osteopontina/genética , Proteínas Represoras/genética , Proteína 1 de Unión a Retinoblastoma , Complejo Correpresor Histona Desacetilasa y Sin3 , Transcripción Genética/genética , Trasplante HeterólogoRESUMEN
Prolonged microgravity experienced by astronauts is associated with a decrease in bone mineral density. To investigate the effect of microgravity on differentiation of osteoclasts and osteoblasts, we used a NASA-recommended, ground-based, microgravity-simulating system, the Rotary Cell Culture System (RCCS). Using the RCCS, we demonstrated that modeled microgravity (MMG) inhibited osteoblastogenesis and increased adipocyte differentiation in human mesenchymal stem cells incubated under osteogenic conditions. This transformation involves reduced RhoA activity and cofilin phosphorylation, disruption of F-actin stress fibers, and decreased integrin signaling through focal adhesion kinase. We have used the system to show that MMG also stimulates osteoclastogenesis. These systems provide the opportunity to develop pharmacological agents that will stimulate osteoblastogenesis and inhibit osteoclastogenesis.
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Diferenciación Celular , Osteoblastos/citología , Osteoclastos/citología , Ingravidez , Animales , Línea Celular , Humanos , RatonesRESUMEN
BACKGROUND: Oxidative stress has been implicated in vascular complications of diabetes mellitus (DM). This study aims to evaluate the relationship between postprandial hypertriglyceridemia (PP-HTG) and oxidative stress in Indian patients of type 2 DM with macrovascular complications. METHODS: Plasma triglycerides (TG), thiobarbituric acid reactive substances (TBARS), erythrocyte reduced glutathione (GSH) and superoxide dismutase (SOD) were measured in fasting and postprandial (PP) state at 2, 4, 6 and 8 h after a high fat meal challenge in controls (Group I) and patients of type 2 DM without (Group II) and with macrovascular complications (Group III). RESULTS: Postprandial TGs increased significantly in patients with type 2 DM, which showed an exaggerated response to high fat meal challenge in Group III as compared to Group II. Highest PP-TBARS were also observed in Group III which correlated positively with TG. However, GSH and SOD were lower in both groups of diabetics as compared to controls. CONCLUSIONS: The magnitude of PP-HTG appears to be the major determinant of oxidative stress in type 2 DM, which along with a compromised antioxidant status may lead to endothelial dysfunction and macrovascular complications.