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1.
Mol Cell ; 66(2): 169-179.e8, 2017 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-28392175

RESUMEN

Mycobacterium tuberculosis (Mtb) is the causative agent of tuberculosis, which kills 1.8 million annually. Mtb RNA polymerase (RNAP) is the target of the first-line antituberculosis drug rifampin (Rif). We report crystal structures of Mtb RNAP, alone and in complex with Rif, at 3.8-4.4 Å resolution. The results identify an Mtb-specific structural module of Mtb RNAP and establish that Rif functions by a steric-occlusion mechanism that prevents extension of RNA. We also report non-Rif-related compounds-Nα-aroyl-N-aryl-phenylalaninamides (AAPs)-that potently and selectively inhibit Mtb RNAP and Mtb growth, and we report crystal structures of Mtb RNAP in complex with AAPs. AAPs bind to a different site on Mtb RNAP than Rif, exhibit no cross-resistance with Rif, function additively when co-administered with Rif, and suppress resistance emergence when co-administered with Rif.


Asunto(s)
Proteínas Bacterianas/metabolismo , ARN Polimerasas Dirigidas por ADN/metabolismo , Regulación Bacteriana de la Expresión Génica , Mycobacterium tuberculosis/enzimología , Mycobacterium tuberculosis/genética , Transcripción Genética , Antituberculosos/metabolismo , Antituberculosos/farmacología , Proteínas Bacterianas/antagonistas & inhibidores , Proteínas Bacterianas/química , Sitios de Unión , ARN Polimerasas Dirigidas por ADN/antagonistas & inhibidores , ARN Polimerasas Dirigidas por ADN/química , Farmacorresistencia Bacteriana , Inhibidores Enzimáticos/metabolismo , Inhibidores Enzimáticos/farmacología , Regulación Bacteriana de la Expresión Génica/efectos de los fármacos , Modelos Moleculares , Mycobacterium tuberculosis/efectos de los fármacos , Unión Proteica , Conformación Proteica , Rifampin/metabolismo , Rifampin/farmacología , Relación Estructura-Actividad , Transcripción Genética/efectos de los fármacos
2.
Antimicrob Agents Chemother ; 65(9): e0262220, 2021 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-34152809

RESUMEN

To combat the looming crisis of antimicrobial-resistant infections, there is an urgent need for novel antimicrobial discovery and drug target identification. The benzoxaborole series was previously identified as an inhibitor of mycobacterial growth. Here, we demonstrate that a benzoxaborole is also active against the Gram-negative bacterium Escherichia coli in vitro. We isolated resistant mutants of E. coli and subjected them to whole-genome sequencing. We found mutations in the enoyl acyl carrier protein FabI. Mutations mapped around the active center site located close to the cofactor binding site. This site partially overlaps with the binding pocket of triclosan, a known FabI inhibitor. Similar to triclosan, the physical interaction of the benzoxaborole with FabI was dependent on the cofactor NAD+. Identification of the putative target of this compound in E. coli provides scope for further development and optimization of this series for Gram-negative pathogens.


Asunto(s)
Enoil-ACP Reductasa (NADH) , Triclosán , Antibacterianos/farmacología , Sitios de Unión , Enoil-ACP Reductasa (NADH)/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo
3.
J Biomed Inform ; 110: 103555, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32916304

RESUMEN

Classification of Homo sapiens cancer genes in molecular level is a challenging research issue as they are extremely pseudo random in nature. Signature gene features need to be exposed to distinctly identify the gene class. Tree-structured filter bank is chosen to perform feature extraction and dimension reduction of the genes. Extracted gene features are fused using Gaussian mixture probability distribution function and identify different cancer classes depending on amount of correlation and exploiting maximum likelihood function. The algorithm is tested on 161 sample gene data of 7 different cancer classes. Sensitivity, specificity, accuracy, precision and F-score are used as metrics to judge the performance of the system and ROC is plotted in comparison with existing electrical network model based classifier. The proposed classifier can identify more than stated number of cancer classes which is a major limitation of the existing electrical network based method. The proposed algorithm is validated by comparing the results with other seven existing image processing based methods.


Asunto(s)
Algoritmos , Neoplasias , Humanos , Procesamiento de Imagen Asistido por Computador , Neoplasias/genética , Distribución Normal , Probabilidad
4.
Hemoglobin ; 44(6): 432-437, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33059511

RESUMEN

Thalassemia and hemoglobinopathies are the most common cause of high morbidity and mortality in India. Detection of carriers and premarital counseling play an important role in preventing the birth of a thalassemic child. The present study aimed to detect large numbers of asymptomatic carriers in rural areas of West Bengal, India. The present cross-sectional study was conducted over a period of 10 years. Thalassemia awareness programs and detection camps were organized at the community level. After signed written consent was obtained, the collected blood samples were subjected to a complete blood count (CBC) in an automated blood cell counter and then analyzed by high performance liquid chromatography (HPLC); in difficult cases, samples were sent to the reference laboratory for molecular characterization. Out of 287,258 samples collected, 32,921 (11.46%) cases revealed abnormal hemoglobins (Hbs); of these, 31,782 (11.06%) carried heterozygous states (carriers/traits), and the remainder were either homozygous or compound heterozygous for different hemoglobinopathies. Two common variants were revealed in the study, namely ß-thalassemia (ß-thal) (7.23%) and Hb E [ß26(B8)Glu→Lys, HBB: c.79G>A] (2.77%) traits. Among homozygous or compound heterozygous states, Hb E/ß-thal (0.14%) and ß-thal major (ß-TM) (0.12%) were predominant. In rural areas of West Bengal, the most common Hb variants detected were ß-thal and Hb E traits. In view of the high prevalence of hemoglobinopathies in this region, routine premarital screening and genetic counseling should be emphasized and encouraged to prevent the birth of a thalassemic child, and thus curtailing the burden on families and the health economy.


Asunto(s)
Hemoglobinopatías/epidemiología , Población Rural , Talasemia alfa/epidemiología , Talasemia beta/epidemiología , Alelos , Biomarcadores , Cromatografía Líquida de Alta Presión , Estudios Transversales , Índices de Eritrocitos , Genotipo , Hemoglobinopatías/diagnóstico , Hemoglobinopatías/etiología , Humanos , India/epidemiología , Tamizaje Masivo , Vigilancia de la Población , Prevalencia , Globinas alfa/genética , Talasemia alfa/diagnóstico , Talasemia alfa/etiología , Globinas beta/genética , Talasemia beta/diagnóstico , Talasemia beta/etiología
5.
Microbiology (Reading) ; 165(5): 492-499, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30775961

RESUMEN

Bacterial persisters are a subpopulation of cells that exhibit phenotypic resistance during exposure to a lethal dose of antibiotics. They are difficult to target and thought to contribute to the long treatment duration required for tuberculosis. Understanding the molecular and cellular biology of persisters is critical to finding new tuberculosis drugs that shorten treatment. This review focuses on mycobacterial persisters and describes the challenges they pose in tuberculosis therapy, their characteristics and formation, how persistence leads to resistance, and the current approaches being used to target persisters within mycobacterial drug discovery.


Asunto(s)
Antituberculosos/farmacología , Descubrimiento de Drogas , Mycobacterium tuberculosis/efectos de los fármacos , Tuberculosis/tratamiento farmacológico , Animales , Humanos , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/fisiología , Tuberculosis/microbiología
6.
Am J Physiol Heart Circ Physiol ; 312(6): H1238-H1247, 2017 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-28432060

RESUMEN

It has been suggested that Toll-like receptor (TLR)4 promotes IL-10-mediated cardiac cell survival, whereas another receptor, TLR2, from the same family, is detrimental. Here, we examined the interactive role of these two innate signaling molecules under stressful conditions, including IL-10 knockout (IL-10-/-) mice, global ischemia-reperfusion (I/R) injury in rat hearts, and in vitro short hairpin RNA experimental models in the presence or absence of IL-10 (10 ng/ml). Circulating and myocardial levels of TNF-α as well as apoptosis and fibrosis were higher in IL-10-/- mice. The increase in TLR2 in IL-10-/- hearts indicated its negative regulation by IL-10. Ex vivo I/R also caused a marked upregulation of TLR2 and TNF-α as well as apoptotic and fibrotic signals. However, a 40-min reperfusion with IL-10 triggered an increase in TLR4 expression and improved recovery of cardiac function. The increase in IL-1 receptor-associated kinase (IRAK)-M and IRAK-2 activity during I/R injury suggested their role in TLR2 signaling. In vitro inhibition of TLR4 activity as a consequence of RNA inhibition-mediated suppression of myeloid differentiation gene (MyD)88 suggested MyD88-dependent activation of TLR4. The inclusion of IL-10 during reperfusion also downregulated the expression of IRAK-2, TNF-α receptor-associated factor 1-interacting protein (TRAIP) and apoptotic signals, caspase-3, and the Bax-to-Bcl-xL ratio. IL-10 reduced the TNF-α receptor-associated increase in TRAIP-induced apoptosis during I/R injury, which led to an increase in IL-1ß to mitigate transforming growth factor-ß receptor type I-mediated fibrosis. The IL-10 mitigation of these changes suggests that the stimulation through TLR4 signaling promotes IRAK-4 and phosphorylates IRAK-1 instead of IRAK-2 and may be an important therapeutic approach in restoring heart health in stress.NEW & NOTEWORTHY Under stress conditions such as downregulation of the IL-10 gene or ischemia-reperfusion injury, Toll-like receptor (TLR)4 and IL-1 receptor-associated kinase (IRAK)-1 activation is suppressed, along with the upregulation of TLR-2 and IRAK-2, resulting in fibrosis and apoptosis. It is suggested that IL-10 helps to maintain heart function during stress via myeloid differentiation gene 88/IRAK-4/IRAK-1-dependent TLR4 signaling.


Asunto(s)
Daño por Reperfusión Miocárdica/metabolismo , Miocardio/metabolismo , Receptor Toll-Like 2/metabolismo , Receptor Toll-Like 4/metabolismo , Animales , Apoptosis , Proteínas Reguladoras de la Apoptosis/metabolismo , Células Cultivadas , Citocinas/metabolismo , Modelos Animales de Enfermedad , Fibrosis , Genotipo , Mediadores de Inflamación/metabolismo , Quinasas Asociadas a Receptores de Interleucina-1/metabolismo , Interleucina-10/deficiencia , Interleucina-10/genética , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados , Factor 88 de Diferenciación Mieloide/genética , Factor 88 de Diferenciación Mieloide/metabolismo , Daño por Reperfusión Miocárdica/patología , Daño por Reperfusión Miocárdica/fisiopatología , Miocardio/patología , Fenotipo , Fosforilación , Interferencia de ARN , Ratas Sprague-Dawley , Transducción de Señal , Receptor Toll-Like 2/genética , Receptor Toll-Like 4/genética , Transfección , Función Ventricular Izquierda
7.
Am J Physiol Heart Circ Physiol ; 309(4): H692-701, 2015 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-26092985

RESUMEN

The recent introduction of novel anticancer therapies, including bevacizumab (BVZ) and sunitinib (SNT), is associated with an increased risk of cardiotoxicity. However, early identification of left ventricular (LV) systolic dysfunction may facilitate dose modification and avoid the development of advanced heart failure. Using a murine model of BVZ- and SNT-mediated cardiotoxicity, we investigated whether cardiac biomarkers and/or tissue velocity imaging (TVI) using echocardiography can detect early changes in cardiac function, before a decrease in LV ejection fraction is identified. A total of 75 wild-type C57Bl/6 male mice were treated with either 0.9% saline, BVZ, or SNT. Serial monitoring of blood pressure, high-sensitivity troponin I, and echocardiographic indexes were performed over a 14-day study period, after which the mice were euthanized for histological and biochemical analyses. Mice treated with either BVZ or SNT developed systemic hypertension as early as day 7, which increased by day 14. Cardiac biomarkers, specifically high-sensitivity troponin I, were not predictive of early LV systolic dysfunction. Although conventional LV ejection fraction values decreased at day 13 in mice treated with either BVZ or SNT, TVI confirmed early LV systolic dysfunction at day 8. Histological and biochemical analysis demonstrated loss of cellular integrity, increased oxidative stress, and increased cardiac apoptosis in mice treated with BVZ or SNT therapy at day 14. In a murine model of BVZ- or SNT-mediated cardiomyopathy, noninvasive assessment by TVI detected early LV systolic dysfunction before alterations in conventional echocardiographic indexes.


Asunto(s)
Anticuerpos Monoclonales Humanizados/efectos adversos , Antineoplásicos/efectos adversos , Corazón/efectos de los fármacos , Indoles/efectos adversos , Miocardio/metabolismo , Pirroles/efectos adversos , Troponina I/sangre , Animales , Bevacizumab , Biomarcadores/sangre , Presión Sanguínea , Cardiotoxicidad/diagnóstico , Cardiotoxicidad/etiología , Ecocardiografía , Corazón/fisiología , Masculino , Ratones , Ratones Endogámicos C57BL , Sunitinib , Función Ventricular Izquierda
8.
J Pediatr Gastroenterol Nutr ; 58(6): 756-61, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24509302

RESUMEN

OBJECTIVES: The present study assesses the safety of ultrasound (US)-guided percutaneous liver biopsies (PLBs) within pediatric liver allograft recipients, describes the pathological results according to early (≤12 months) and late (>12 months) posttransplantation periods, and analyzes the value of liver function tests (LFTs) and Doppler US variables in determining these results. METHODS: A total of 219 US-guided PLBs in 85 pediatric patients with liver transplant (mean age 7 ±â€Š5 years, range: 6 months to 18 years) performed between March 2005 and May 2012 were retrospectively evaluated at a single institution. Doppler US and LFT evaluation (including total bilirubin, alanine aminotransferase, aspartate aminotransferase, γ-glutamyl transferase, alkaline phosphatase) occurred within 1 day of early (n = 92, 42%) and late term (n = 127, 58%) posttransplantation biopsies. RESULTS: The rate of major complications (hemorrhage requiring blood transfusion) was 0.91% (n = 2). The early versus late term biopsy results, respectively, included: cholestasis at 36% versus 18% (P = 0.003), minimal changes 16% versus 24% (not significant [NS]), acute rejection 13% versus 5% (P = 0.027), inflammatory diseases 15% versus 15% (NS), indeterminate acute rejection 11% versus 7% (NS), chronic rejection 4% versus 14% (P = 0.017), fibrotic diseases 4% versus 12% (NS), and other 0% versus 5% (NS). Neither LFT nor US variables were correlated with pathological outcomes. CONCLUSIONS: The rate of complications in pediatric patients after US-guided liver biopsy is low. A range of pathological results exists between early and late posttransplantation liver biopsies. LFT and Doppler US findings are not predictors of pathological results.


Asunto(s)
Biopsia/métodos , Colestasis/epidemiología , Rechazo de Injerto/epidemiología , Hemorragia/etiología , Trasplante de Hígado , Hígado/patología , Complicaciones Posoperatorias , Adolescente , Bilirrubina/sangre , Biopsia/efectos adversos , Niño , Preescolar , Fibrosis/epidemiología , Hemorragia/epidemiología , Humanos , Lactante , Inflamación/epidemiología , Hígado/enzimología , Hígado/cirugía , Pruebas de Función Hepática/métodos , Complicaciones Posoperatorias/epidemiología , Prevalencia , Estudios Retrospectivos , Receptores de Trasplantes , Ultrasonografía/métodos
9.
Pediatr Cardiol ; 35(3): 441-9, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24096719

RESUMEN

The aim of this study was to use multidetector computed tomography (MDCT) and magnetic resonance (MRA) angiography to illustrate the classification and clinical characteristics of single coronary artery anomaly (SCAA). Retrospective evaluation of 22 adult and pediatric patients with SCAA by way of a medical archiving system was performed between June 2001 and August 2012. Imaging modalities used for coronary artery evaluation included MRA and MDCT angiography. Of the 22 patients, the majority (n = 8; 36%) showed an interarterial course, the subtype having the worst prognosis. The retroaortic course (n = 3; 14%) and course anterior to the pulmonary trunk (n = 3; 14%) were the next most frequent patterns. Additional types (n = 8; 36%) included the following: L-I, R-III, septal, and combined. Four patients (18%) showed atherosclerotic involvement. SCAA anomaly was diagnosed as an incidental finding in the majority of patients evaluated initially for cardiovascular diseases (n = 19; 86%). Two patients (9%) required surgical interventions solely for their anomaly. Nine patients (41%) were found to have coexisting congenital heart disease. Although conventional catheter angiography is responsible for the current classification of SCAA, advanced imaging modalities are useful in the evaluation of morphological and clinical characteristics of single coronary arteries.


Asunto(s)
Anomalías de los Vasos Coronarios/diagnóstico , Angiografía por Resonancia Magnética/métodos , Tomografía Computarizada por Rayos X/métodos , Adolescente , Adulto , Anciano , Niño , Medios de Contraste , Angiografía Coronaria , Anomalías de los Vasos Coronarios/clasificación , Ecocardiografía , Electrocardiografía , Femenino , Humanos , Imagenología Tridimensional , Lactante , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
10.
J Biol Chem ; 286(1): 42-9, 2011 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-21071437

RESUMEN

Activated by the RAS-MAPK signaling pathway, MSK1 is recruited to immediate-early gene (IEG) regulatory regions, where it phosphorylates histone H3 at Ser-10 or Ser-28. Chromatin remodelers and modifiers are then recruited by 14-3-3 proteins, readers of phosphoserine marks, leading to the occupancy of IEG promoters by the initiation-engaged form of RNA polymerase II and the onset of transcription. In this study, we show that this mechanism of IEG induction, initially elucidated in parental 10T1/2 murine fibroblast cells, applies to metastatic Hras1-transformed Ciras-3 cells. As the RAS-MAPK pathway is constitutively activated in Ciras-3 cells, MSK1 activity and phosphorylated H3 steady-state levels are elevated. We found that steady-state levels of the IEG products AP-1 and COX-2 were also elevated in Ciras-3 cells. When MSK1 activity was inhibited or MSK1 expression was knocked down in Ciras-3 cells, the induction of IEG expression and the steady-state levels of COX-2, FRA-1, and JUN were greatly reduced. Furthermore, MSK1 knockdown Ciras-3 cells lost their malignant phenotype, as reflected by the absence of anchorage-independent growth.


Asunto(s)
Transformación Celular Neoplásica , Fibroblastos/metabolismo , Fibroblastos/patología , Proteína Oncogénica p21(ras)/genética , Proteínas Quinasas S6 Ribosómicas 90-kDa/metabolismo , Proteínas 14-3-3/metabolismo , Animales , Línea Celular , Ensamble y Desensamble de Cromatina/efectos de los fármacos , Ciclooxigenasa 2/metabolismo , Fibroblastos/citología , Genes Inmediatos-Precoces/genética , Histonas/metabolismo , Isoquinolinas/farmacología , Ratones , Fenotipo , Ésteres del Forbol/farmacología , Fosforilación/efectos de los fármacos , Proteínas Proto-Oncogénicas c-fos/metabolismo , Proteínas Proto-Oncogénicas c-jun/metabolismo , Secuencias Reguladoras de Ácidos Nucleicos/genética , Proteínas Quinasas S6 Ribosómicas 90-kDa/antagonistas & inhibidores , Sulfonamidas/farmacología , Activación Transcripcional/efectos de los fármacos
11.
Pediatr Cardiol ; 33(2): 215-21, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21910019

RESUMEN

Noncompaction of the left ventricle, a genetic cardiomyopathy with a reported incidence of 0.05% to 0.24%, can lead to sudden cardiac death, particularly among children, if left undetected. Because the diagnosis of isolated noncompaction cardiomyopathy (NCM) can be overlooked, its association with other congenital heart diseases (CHDs) makes the diagnosis of NCM even more difficult. This study aimed to assess the impact of NCM on the cardiovascular physiology of children with coexisting CHDs evaluated by cardiovascular magnetic resonance imaging. A case-control study was performed with 12 children (6 patients with combined NCM and CHD and 6 control subjects with isolated CHD). The mean left ventricular end-diastolic and end-systolic volume indices were significantly higher in the CHD patients presenting with NCM than in the CHD patients with no NCM (P = 0.028). However, no differences were observed for right ventricular end-diastolic and end-systolic volume indices, biventricular ejection fractions, stroke volumes and indices, left ventricular wall thickness, left ventricular fractional shortening, cardiac output, or cardiac index. This study suggests that NCM in children with CHDs increases left ventricular volumes, and larger studies are required to demonstrate other changes (e.g., ejection fraction, stroke volume) that were close to being significant.


Asunto(s)
No Compactación Aislada del Miocardio Ventricular/diagnóstico , No Compactación Aislada del Miocardio Ventricular/fisiopatología , Imagen por Resonancia Magnética , Adolescente , Estudios de Casos y Controles , Niño , Femenino , Cardiopatías Congénitas/fisiopatología , Humanos , Masculino , Adulto Joven
12.
Trans Indian Natl Acad Eng ; 7(3): 809-821, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35836616

RESUMEN

Healthcare facilities, especially in highly populated countries like India where patient to doctor ratio is very high, are under a huge burden. Thus, Remote Patient Physiological Parameter Monitoring using Embedded System (RP3MES) becomes essential to monitor a large number of people admitted in hospitals and also patients afflicted with infectious diseases. The design for RP3MES addresses the key issues of portability, cost-effectiveness, low power consumption, user-friendliness, high accuracy and remote communication to facilitate vital parameter(s), like heart rate and body temperature, measurements and emergency notification, keeping in mind, the health of the caregiver(s). ARM Cortex M3 embedded processor and low-cost sensors are used to achieve the cost-effectiveness and low power consumption. Alarming unit intimidates a remote caregiver regarding their patient's health condition. The accuracy of the system measured data is 99.4% compared with the gold standard, which has been verified using Lin's Concordance Correlation Coefficient and Bland-Altman analysis. A comparison of our system with other commercially available ones is also presented here. The proposed system has wireless connectivity which minimizes infection transmission among family members and caregivers of the patients. It may also reduce the burden on healthcare staffs in hospitals.

13.
Med Biol Eng Comput ; 59(3): 673-691, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33595791

RESUMEN

Classification of Homo sapiens gene behavior employing computational biology is a recent research trend. But monitoring gene activity profile and genetic behavior from the alphabetic DNA sequence using a non-invasive method is a tremendous challenge in functional genomics. The present paper addresses such issue and attempts to differentiate Homo sapiens genes using linear discriminant analysis (LDA) method. Annotated protein coding sequences of Homo sapiens genes, collected from NCBI, are taken as test samples. Minimum entropy-based mapping (MEM) technique assists to extract highest information from the numerical DNA sequences. The proposed LDA technique has successfully classified Homo sapiens genes based on the following features: composition of hydrophilic amino acids, dominance of arginine amino acid, and magnitude and size of individual amino acids. The proposed algorithm is successfully tested on 84 Homo sapiens healthy and cancer genes of the prostate and breast cells. Classification performance of the proposed LDA technique is judged by sensitivity (89.12%), specificity (91.9%), accuracy (90.87%), F1 score (92.03%), Matthews' correlation coefficients (81.04%), and miss rate (9.12%), and it outperforms other four existing classifiers. The results are cross-validated through Rayleigh PDF and mutual information technique. Fisher test, 2-sample T-test, and relative entropy test are considered to verify the efficacy of the present classifier.


Asunto(s)
Algoritmos , Biología Computacional , Aminoácidos , Análisis Discriminante , Entropía , Humanos , Masculino
14.
J Pediatr Surg ; 56(5): 1051-1056, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33092814

RESUMEN

BACKGROUND: Spontaneous intestinal perforation (SIP) and necrotizing enterocolitis (NEC) are complications of extremely low birth weight (ELBW, ≤1000 g) infants. ELBW infants at Texas Children's Hospital receive an exclusive human milk-based diet, which has been associated with a reduction of NEC. OBJECTIVES: 1) Assess incidence of SIP and NEC (Stage II or greater) in ELBW infants receiving 100% human milk-based diet, 2) Describe mortality rates of ELBW infants with SIP and NEC. METHODS: Prospective single-center observational cohort study of ELBW infants born between 2010 and 2014 with SIP or NEC (exclusion: congenital anomalies and death within 48 h). RESULTS: Of 379 ELBW infants, 345 were eligible. Of these, 28 (8.1%) had SIP and 8 (2.3%) had NEC (medical n = 1, surgical n = 7). SIP infant mortality was 32% (n = 9) compared to 63% (n = 5) for NEC patients. Of SIP infants with PD (n = 25), 52% required subsequent exploratory laparotomy (LAP). Of NEC infants with peritoneal drainage (PD) (n = 2), both required subsequent LAP. CONCLUSION: Using an exclusive human milk-based diet, the incidence of SIP exceeds NEC in ELBW infants at our institution. This shows a changing trend in the incidence of these two diagnoses in the era of human milk, as NEC had previously been more prevalent in ELBW infants. More than half of infants who initially received PD later required LAP. There were no differences in survival outcomes in both SIP and NEC groups based on surgical management.


Asunto(s)
Enterocolitis Necrotizante , Perforación Intestinal , Niño , Dieta , Enterocolitis Necrotizante/epidemiología , Humanos , Incidencia , Lactante , Recien Nacido con Peso al Nacer Extremadamente Bajo , Recién Nacido , Perforación Intestinal/epidemiología , Perforación Intestinal/etiología , Perforación Intestinal/cirugía , Leche Humana , Estudios Prospectivos , Texas/epidemiología
15.
J Cell Physiol ; 224(1): 28-32, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20301197

RESUMEN

The cyclin-dependent kinase inhibitor protein p21(Waf1/Cip1) is a potent tumor suppressor. Here, we demonstrate that estradiol regulates the p21(Waf1/Cip1) gene. Estradiol induces p21(Waf1/Cip1) mRNA expression within 30-60 min independent of new protein synthesis in the estrogen receptor alpha (ER alpha) positive human breast cancer cell line MCF-7. Similar to other estradiol responsive promoters, the p21(Waf1/Cip1) upstream promoter region has several estrogen response element (ERE) half-sites nestled in AP-1 binding sites, which are positioned upstream to Sp1 binding sites. Using the chromatin immunoprecipitation (ChIP) assay, we show that estradiol stimulation resulted in the recruitment of transcription factors ER alpha, Sp1, and Sp3 to the p21(Waf1/Cip1) upstream promoter element. The Sp1 inhibitor mithramycin A abrogated Sp1, and to a lesser extent Sp3 binding, and markedly reduced the estradiol stimulated p21(Waf1/Cip1) gene expression. However, ER alpha binding was not affected in the mithramycin A and estradiol treated cells. On closer examination of the half-site ERE/AP-1 sites upstream to the Sp1 sites in a separate ChIP experiment, we found a pronounced association of ER alpha upon estradiol treatment compared to almost negligible binding of Sp1 or Sp3. Together these studies provide evidence that ER alpha is recruited to the half-site ERE/AP-1 sites in the p21(Waf1/Cip1) upstream promoter element. Although Sp1/Sp3 is not involved in the recruitment of ER alpha to the promoter, Sp1 is necessary for estrogen-induced p21(Waf1/Cip1) promoter activity.


Asunto(s)
Neoplasias de la Mama/genética , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/genética , Estradiol/metabolismo , Receptor alfa de Estrógeno/metabolismo , Regulación Neoplásica de la Expresión Génica , Sitios de Unión , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Línea Celular Tumoral , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Femenino , Humanos , Plicamicina/análogos & derivados , Plicamicina/farmacología , ARN Mensajero/metabolismo , Elementos de Respuesta , Factor de Transcripción Sp1/antagonistas & inhibidores , Factor de Transcripción Sp1/metabolismo , Factor de Transcripción Sp3/metabolismo , Factores de Tiempo , Factor de Transcripción AP-1/metabolismo , Regulación hacia Arriba
16.
JPEN J Parenter Enteral Nutr ; 32(1): 51-6, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18165447

RESUMEN

BACKGROUND: In vitro, butyrate inhibits histone deacetylase and down-regulates expression of cyclin D1. We hypothesized that an increased entry rate of butyrate into the cecal lumen would have similar effects in vivo. METHODS: We used frozen cecal tissue and data from previous studies, one showing that lactulose supplementation caused an increased rate of cecal synthesis of butyrate and decreased cecal cell proliferation and density of clostridia and the other showing that cecal cell proliferation was increased by an exogenous cecal butyrate infusion at a comparable rate. The ratio of acetylated to total histones (AH ratio) and cyclin D1 mRNA expression were measured in cecal tissue. RESULTS: Lactulose supplementation caused a 189% increase in the AH ratio (p = .004), which inversely correlated with cecal cell proliferation (r = -0.782; p = .008). With cecal butyrate infusion, we observed a significant decrease in histone acetylation (p = .02), which also inversely correlated with cecal cell proliferation (r = -0.797; p = .002). Cyclin D1 expression was increased 6.5-fold by lactulose feeding (p = .02) but decreased 50% with cecal butyrate infusion (p = .004). CONCLUSIONS: The effects on histone acetylation of increased "endogenous" butyrate production produced by lactulose feeding, but not exogenous cecal infusion of butyrate, mirror those in vitro. Thus, bacterial production and exogenous infusion of butyrate have opposite effects on histone acetylation and cyclin D1 expression, suggesting that the composition of bacterial flora may play a role in butyrate's in vivo effects on the cell cycle.


Asunto(s)
Bacterias/metabolismo , Butiratos/farmacología , Ciego/metabolismo , Ciclina D1/metabolismo , Histonas/metabolismo , Animales , Proliferación Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Fármacos Gastrointestinales/farmacología , Regulación de la Expresión Génica , Inhibidores de Histona Desacetilasas , Histonas/efectos de los fármacos , Lactulosa/farmacología , Porcinos
17.
BMC Cancer ; 7: 181, 2007 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-17883861

RESUMEN

BACKGROUND: The sex hormone estrogen (E2) is pivotal to normal mammary gland growth and differentiation and in breast carcinogenesis. In this in silico study, we examined metabolic differences between ER(+)ve breast cancer cells during E2 deprivation. METHODS: Public repositories of SAGE and MA gene expression data generated from E2 deprived ER(+)ve breast cancer cell lines, MCF-7 and ZR75-1 were compared with normal breast tissue. We analyzed gene ontology (GO), enrichment, clustering, chromosome localization, and pathway profiles and performed multiple comparisons with cell lines and tumors with different ER status. RESULTS: In all GO terms, biological process (BP), molecular function (MF), and cellular component (CC), MCF-7 had higher gene utilization than ZR75-1. Various analyses showed a down-regulated immune function, an up-regulated protein (ZR75-1) and glucose metabolism (MCF-7). A greater percentage of 77 common genes localized to the q arm of all chromosomes, but in ZR75-1 chromosomes 11, 16, and 19 harbored more overexpressed genes. Despite differences in gene utilization (electron transport, proteasome, glycolysis/gluconeogenesis) and expression (ribosome) in both cells, there was an overall similarity of ZR75-1 with ER(-)ve cell lines and ER(+)ve/ER(-)ve breast tumors. CONCLUSION: This study demonstrates integral metabolic differences may exist within the same cell subtype (luminal A) in representative ER(+)ve cell line models. Selectivity of gene and pathway usage for strategies such as energy requirement minimization, sugar utilization by ZR75-1 contrasted with MCF-7 cells, expressing genes whose protein products require ATP utilization. Such characteristics may impart aggressiveness to ZR75-1 and may be prognostic determinants of ER(+)ve breast tumors.


Asunto(s)
Neoplasias de la Mama/genética , Regulación Neoplásica de la Expresión Génica/fisiología , Redes y Vías Metabólicas/genética , Receptores de Estrógenos/biosíntesis , Receptores de Estrógenos/genética , Transducción de Señal/genética , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Línea Celular Tumoral , Estradiol/metabolismo , Femenino , Humanos , Receptores de Estrógenos/fisiología
18.
Can J Cardiol ; 32(12): 1513-1519, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27650929

RESUMEN

BACKGROUND: In the breast cancer setting, anticancer therapies including doxorubicin (DOX) and trastuzumab (TRZ) are associated with a significantly increased risk of cardiotoxicity. Despite the increasing support for the role of oxidative stress (OS) in its pathophysiology, we still do not have an optimal antioxidant for the prevention of DOX + TRZ-mediated cardiac dysfunction. The objective of this study was to investigate whether the novel antioxidant N-acetylcysteine amide (NACA) can attenuate DOX + TRZ-induced heart failure in a murine model. METHODS: A total of 100 C57Bl/6 female mice received 1 of the following drug regimens: (1) saline, (2) NACA, (3) DOX, (4) TRZ, (5) DOX + TRZ, (6) NACA + DOX, (7) NACA + TRZ, and (8) NACA + DOX + TRZ. Serial echocardiography was performed over a 10-day study period, after which the mice were killed for histologic and biochemical analyses. RESULTS: In mice receiving DOX, the left ventricular ejection fraction (LVEF) decreased from 73% ± 4% to 43% ± 2% on day 10. In mice receiving DOX + TRZ, the LVEF decreased from 72% ± 3% to 32% ± 2% on day 10. Prophylactic administration of NACA to mice receiving DOX or DOX + TRZ was cardioprotective, with an LVEF of 62% ± 3% and 55% ± 3% on day 10, respectively. Histologic and biochemical analyses demonstrated a loss of cellular integrity, increased OS, and increased cardiac apoptosis in mice treated with DOX + TRZ, which was attenuated by the prophylactic administration of NACA. CONCLUSIONS: NACA attenuated the cardiotoxic side effects of DOX + TRZ in a murine model of chemotherapy-induced cardiac dysfunction by decreasing OS and apoptosis.


Asunto(s)
Acetilcisteína/análogos & derivados , Cardiotoxicidad , Doxorrubicina/efectos adversos , Trastuzumab/efectos adversos , Acetilcisteína/farmacología , Animales , Antineoplásicos/administración & dosificación , Antineoplásicos/efectos adversos , Antioxidantes/farmacología , Cardiotónicos/farmacología , Cardiotoxicidad/diagnóstico , Cardiotoxicidad/etiología , Cardiotoxicidad/prevención & control , Modelos Animales de Enfermedad , Doxorrubicina/administración & dosificación , Monitoreo de Drogas , Ecocardiografía/métodos , Femenino , Ratones , Estrés Oxidativo/efectos de los fármacos , Trastuzumab/administración & dosificación , Resultado del Tratamiento
19.
Indian J Ophthalmol ; 50(4): 287-93, 2002 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12532493

RESUMEN

PURPOSE: This study aimed to investigate the safety and efficacy of trabeculectomy with intraoperative mitomycin C (MMC) in the management of eyes with neovascular glaucoma (NVG). METHODS: Fifteen eyes of 14 patients with NVG were included in the study. NVG was secondary to central retinal vein occlusion (3 eyes), hemiretinal vein occlusion (2 eyes), proliferative diabetic retinopathy (8 eyes), branch retinal vein occlusion (1 eye) and idiopathic (1 eye). Preoperative retinal ablation was performed in eyes with evidence of posterior segment ischaemia. Following this, all eyes underwent trabeculectomy with intraoperative MMC (0.4 mg/ml for 3 minutes). Clinical outcome assessment included visual acuity, intraocular pressure (IOP), bleb appearance, identification of complications and antiglaucoma medications required to control IOP. RESULTS: The mean IOP decreased from 38.6 +/- 12.9 mmHg (range, 15-64 mmHg) to 17.4 +/- 9.33 mmHg (range, 4-34 mmHg) (P = 0.001). Preoperative visual acuity ranged from light perception to 6/9 in the affected eye. Thirteen (86.6%) of 15 eyes improved vision or retained preoperative vision, one (6.7%) eye lost light perception and one (6.7%) eye developed tractional retinal detachment two years after trabeculectomy. Ten (66.7%) of 15 eyes were classified as surgical success with a mean follow-up of 28.6 +/- 26.3 months (range, 2-82 months). None of the patients developed choroidal haemorrhage, hypotony maculopathy, late onset bleb leak or endophthalmitis. CONCLUSION: Trabeculectomy with intraoperative MMC is a good treatment modality in the management of eyes with NVG.


Asunto(s)
Antibióticos Antineoplásicos/uso terapéutico , Glaucoma Neovascular/terapia , Mitomicina/uso terapéutico , Trabeculectomía/métodos , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Presión Intraocular , Masculino , Persona de Mediana Edad , Proyectos Piloto , Complicaciones Posoperatorias , Estudios Prospectivos , Seguridad , Resultado del Tratamiento , Agudeza Visual
20.
PLoS One ; 7(1): e28395, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22253690

RESUMEN

In this study we have calculated a 3D structure of apoptin and through modeling and docking approaches, we show its interaction with Bcr-Abl oncoprotein and its downstream signaling components, following which we confirm some of the newly-found interactions by biochemical methods. Bcr-Abl oncoprotein is aberrantly expressed in chronic myelogenous leukaemia (CML). It has several distinct functional domains in addition to the Abl kinase domain. The SH3 and SH2 domains cooperatively play important roles in autoinhibiting its kinase activity. Adapter molecules such as Grb2 and CrkL interact with proline-rich region and activate multiple Bcr-Abl downstream signaling pathways that contribute to growth and survival. Therefore, the oncogenic effect of Bcr-Abl could be inhibited by the interaction of small molecules with these domains. Apoptin is a viral protein with well-documented cancer-selective cytotoxicity. Apoptin attributes such as SH2-like sequence similarity with CrkL SH2 domain, unique SH3 domain binding sequence, presence of proline-rich segments, and its nuclear affinity render the molecule capable of interaction with Bcr-Abl. Despite almost two decades of research, the mode of apoptin's action remains elusive because 3D structure of apoptin is unavailable. We performed in silico three-dimensional modeling of apoptin, molecular docking experiments between apoptin model and the known structure of Bcr-Abl, and the 3D structures of SH2 domains of CrkL and Bcr-Abl. We also biochemically validated some of the interactions that were first predicted in silico. This structure-property relationship of apoptin may help in unlocking its cancer-selective toxic properties. Moreover, such models will guide us in developing of a new class of potent apoptin-like molecules with greater selectivity and potency.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas de la Cápside/metabolismo , Diseño de Fármacos , Proteínas de Fusión bcr-abl/metabolismo , Modelos Moleculares , Proteínas Nucleares/metabolismo , Proteínas Adaptadoras Transductoras de Señales/química , Secuencias de Aminoácidos , Secuencia de Aminoácidos , Aminoácidos/metabolismo , Animales , Proteínas de la Cápside/química , Proteínas de la Cápside/toxicidad , Muerte Celular/efectos de los fármacos , Núcleo Celular/efectos de los fármacos , Núcleo Celular/metabolismo , Biología Computacional , Regulación hacia Abajo/efectos de los fármacos , Proteínas de Fusión bcr-abl/química , Humanos , Enlace de Hidrógeno/efectos de los fármacos , Ratones , Datos de Secuencia Molecular , Proteínas Nucleares/química , Fosforilación/efectos de los fármacos , Unión Proteica/efectos de los fármacos , Transporte de Proteínas/efectos de los fármacos , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Transducción de Señal/efectos de los fármacos , Homología Estructural de Proteína , Dominios Homologos src
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