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1.
J Mol Biol ; 436(6): 168483, 2024 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-38331211

RESUMEN

RAF protein kinases are essential effectors in the MAPK pathway and are important cancer drug targets. Structural understanding of RAF activation is so far based on cryo-electron microscopy (cryo-EM) and X-ray structures of BRAF in different conformational states as inactive or active complexes with KRAS, 14-3-3 and MEK1. In this study, we have solved the first cryo-EM structures of CRAF2/14-3-32 at 3.4 Å resolution and CRAF2/14-3-32/MEK12 at 4.2 Å resolution using CRAF kinase domain expressed as constitutively active Y340D/Y341D mutant in insect cells. The overall architecture of our CRAF2/14-3-32 and CRAF2/14-3-32/MEK12 cryo-EM structures is highly similar to corresponding BRAF structures in complex with 14-3-3 or 14-3-3/MEK1 and represent the activated dimeric RAF conformation. Our CRAF cryo-EM structures provide additional insights into structural understanding of the activated CRAF2/14-3-32/MEK12 complex.


Asunto(s)
Proteínas 14-3-3 , MAP Quinasa Quinasa 1 , Proteínas Proto-Oncogénicas c-raf , Antineoplásicos/química , Microscopía por Crioelectrón , Proteínas 14-3-3/química , MAP Quinasa Quinasa 1/química , Proteínas Proto-Oncogénicas c-raf/química , Conformación Proteica
2.
Int J Mol Sci ; 25(3)2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38338957

RESUMEN

Patients suffering from chronic fatigue syndrome (CFS) or post-COVID syndrome (PCS) exhibit a reduced physiological performance capability. Impaired mitochondrial function and morphology may play a pivotal role. Thus, we aimed to measure the muscle mitochondrial oxidative phosphorylation (OXPHOS) capacity and assess mitochondrial morphology in CFS and PCS patients in comparison to healthy controls (HCs). Mitochondrial OXPHOS capacity was measured in permeabilized muscle fibers using high-resolution respirometry. Mitochondrial morphology (subsarcolemmal/intermyofibrillar mitochondrial form/cristae/diameter/circumference/area) and content (number and proportion/cell) were assessed via electron microscopy. Analyses included differences in OXPHOS between HC, CFS, and PCS, whereas comparisons in morphology/content were made for CFS vs. PCS. OXPHOS capacity of complex I, which was reduced in PCS compared to HC. While the subsarcolemmal area, volume/cell, diameter, and perimeter were higher in PCS vs. CFS, no difference was observed for these variables in intermyofibrillar mitochondria. Both the intermyofibrillar and subsarcolemmal cristae integrity was higher in PCS compared to CFS. Both CFS and PCS exhibit increased fatigue and impaired mitochondrial function, but the progressed pathological morphological changes in CFS suggest structural changes due to prolonged inactivity or unknown molecular causes. Instead, the significantly lower complex I activity in PCS suggests probably direct virus-induced alterations.


Asunto(s)
COVID-19 , Síndrome de Fatiga Crónica , Humanos , Síndrome de Fatiga Crónica/metabolismo , COVID-19/complicaciones , COVID-19/metabolismo , Mitocondrias Musculares/metabolismo , Mitocondrias , Fibras Musculares Esqueléticas/metabolismo
3.
Nutrients ; 14(17)2022 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-36079816

RESUMEN

Lifestyle interventions can have a positive impact on quality of life and psychological parameters in patients with metabolic syndrome (MetS). In this randomized controlled trial, 145 participants with MetS (62.8% women; 59.7 ± 9.3 years) were randomized to (1) 5-day fasting followed by 10 weeks of lifestyle modification (F + LM; modified DASH diet, exercise, mindfulness; n = 73) or (2) 10 weeks of lifestyle modification only (LM; n = 72). Outcomes were assessed at weeks 0, 1, 12, and 24, and included quality of life (Short-Form 36 Health Survey Questionnaire, SF-36), anxiety/depression (Hospital Anxiety and Depression Scale, HADS), stress (Cohen Perceived Stress Scale, CPSS), mood (Profile of Mood States, POMS), self-efficacy (General Self-Efficacy Scale, GSE), mindfulness (Mindfulness Attention Awareness Scale, MAAS), and self-compassion (Self-Compassion Scale, SCS). At week 1, POMS depression and fatigue scores were significantly lower in F + LM compared to LM. At week 12, most self-report outcomes improved in both groups-only POMS vigor was significantly higher in F + LM than in LM. Most of the beneficial effects within the groups persisted at week 24. Fasting can induce mood-modulating effects in the short term. LM induced several positive effects on quality of life and psychological parameters in patients with MetS.


Asunto(s)
Síndrome Metabólico , Calidad de Vida , Depresión/psicología , Depresión/terapia , Ayuno , Femenino , Humanos , Estilo de Vida , Masculino , Síndrome Metabólico/terapia , Medición de Resultados Informados por el Paciente , Calidad de Vida/psicología
4.
J Clin Med ; 11(16)2022 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-36012990

RESUMEN

BACKGROUND: Lifestyle interventions, such as fasting, diet, and exercise, are increasingly used as a treatment option for patients with metabolic syndrome (MS). This study assesses the efficacy and safety of fasting followed by lifestyle modification in patients with MS compared to lifestyle modification only. METHODS: Single-blind, multicenter, parallel, randomized controlled trial in two German tertiary referral hospitals in metropolitan areas. INTERVENTIONS: (a) 5-day fasting followed by 10 weeks of lifestyle modification (modified DASH diet, exercise, mindfulness; n = 73); (b) 10 weeks of lifestyle modification only (n = 72). MAIN OUTCOMES AND MEASURES: Co-primary outcomes were ambulatory systolic blood pressure and the homeostasis model assessment (HOMA) index at week 12. Further outcomes included anthropometric, laboratory parameters, and the PROCAM score at weeks 1, 12, and 24. RESULTS: A total of 145 patients with metabolic syndrome (62.8% women; 59.7 ± 9.3 years) were included. No significant group differences occurred for the co-primary outcomes at week 12. However, compared to lifestyle modification only, fasting significantly reduced HOMA index (Δ = -0.8; 95% confidence interval [CI] = -1.7, -0.1), diastolic blood pressure (Δ = -4.8; 95% CI = -5.5, -4.1), BMI (Δ = -1.7; 95% CI = -2.0, -1.4), weight (Δ = -1.7; 95% CI = -2.0, -1.4), waist circumference (Δ = -2.6; 95% CI = -5.0, -0.2), glucose (Δ = -10.3; 95% CI = -19.0, -1.6), insulin (Δ = -2.9; 95% CI = -5.3, -0.4), HbA1c (Δ = -0.2; 95% CI = -0.4, -0.05;), triglycerides (Δ = -48.9; 95% CI = -81.0, -16.9), IL-6 (Δ = -1.2; 95% CI = -2.5, -0.005), and the 10-year risk of acute coronary events (Δ = -4.9; 95% CI = -9.5, -0.4) after week 1. Fasting increased uric acid levels (Δ = 1.0; 95% CI = 0.1, 1.9) and slightly reduced eGRF (Δ = -11.9; 95% CI = -21.8, -2.0). Group differences at week 24 were found for weight (Δ = -2, 7; 95% CI = -4.8, -0.5), BMI (Δ = -1.0; 95% CI = -1.8, -0.3), glucose (Δ = -7.7; 95% CI = -13.5, -1.8), HDL (Δ = 5.1; 95% CI = 1.5, 8.8), and CRP (Δ = 0.2; 95% CI = 0.03, 0.4). No serious adverse events occurred. CONCLUSIONS: A beneficial effect at week 24 was found on weight; fasting also induced various positive short-term effects in patients with MS. Fasting can thus be considered a treatment for initializing lifestyle modification for this patient group; however, it remains to be investigated whether and how the multilayered effects of fasting can be maintained in the medium and longer term.

5.
Sci Data ; 9(1): 56, 2022 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-35169142

RESUMEN

This paper describes a dataset of residential electricity household and heat pump load profiles, measured in 38 single-family houses in Northern Germany. We provide data per household of apparent, active and reactive power (W), voltage (V), current (A) and the power factor (no unit) in 10 seconds to 60 minutes temporal resolution from May 2018 to the end of 2020. We validated the dataset both in itself, comparing different measurements that should produce the same results, and externally to standard load profiles and found no major inconsistencies. We identified an average consumption per single-family house with 2.38 inhabitants of 2829 kWh for the household and an additional 4993 kWh for the heat pump. The dataset can support the understanding of patterns in electrical load curves and can help to estimate the additional load on distribution networks induced by heat pumps.

6.
J Pharm Pract ; 34(3): 360-364, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31451019

RESUMEN

BACKGROUND: Epidemiology and risk factors for bacteremia in pediatric and adolescent patients have not been fully elucidated. OBJECTIVE: The purpose of this study was to identify primary causative agents of bacteremia in pediatric and adolescent patients and associated risk factors. We hypothesized that these would be different than those seen in adults. PATIENTS AND METHODS: This retrospective cohort, epidemiologic evaluation included patients admitted to a tertiary referral center from January 01, 2013, to December 31, 2015. Patients <18 years old with a confirmed positive blood culture were included; the first positive culture per organism per patient was analyzed. The primary outcome was to determine the most frequent causative organisms of bacteremia; the secondary outcome was an evaluation of risk factors for acquiring staphylococcal bacteremia. RESULTS: A total of 913 isolates were evaluated, including 92 unique organisms. The most frequently identified were Staphylococcus epidermidis (238/913, 26.1%), followed by Staphylococcus aureus (136/913, 14.9%). Methicillin resistance was observed in 60.3% of S aureus. Two hundred thirty-six patients were included in the risk factor analysis. Prematurity, previous antibiotics, and intubation/ventilation were more likely associated with S epidermidis (P < .001, P < .001, and P = .032, respectively). Patients with a recent or previous hospitalization and those with dermatitis/eczema were statistically more likely to grow S aureus (P < .001, P = .029, respectively). CONCLUSIONS: Although epidemiology of organisms associated with pediatric and adolescent bacteremia was similar to adults, risk factors were different than seen in that population. Further understanding of these risk factors may be helpful in developing preemptive infection control strategies in patients at risk.


Asunto(s)
Bacteriemia , Staphylococcus aureus Resistente a Meticilina , Infecciones Estafilocócicas , Adolescente , Adulto , Bacteriemia/diagnóstico , Bacteriemia/epidemiología , Niño , Humanos , Resistencia a la Meticilina , Estudios Retrospectivos , Factores de Riesgo , Infecciones Estafilocócicas/diagnóstico , Infecciones Estafilocócicas/epidemiología
7.
Semin Cancer Biol ; 68: 92-104, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-31734137

RESUMEN

Malignant gliomas are still extremely difficult to treat because complete surgical resection is biologically not feasible due to the invasive nature of these diseases and the proximity of tumors to functionally sensitive areas. Moreover, adjuvant therapies are facing a strong therapeutic resistance since the central nervous system is a highly protected environment and the tumor cells display a vast intra-tumoral genetic and epigenetic variation. As a consequence, new therapeutics are urgently needed but the process of developing novel compounds that finally reach clinical application is highly time-consuming and expensive. Drug repurposing is an approach to facilitate and accelerate the discovery of new cancer treatments. In malignant glioma, like in other cancers, pre-existing physiological pathways that regulate cell growth, cell death or cell migration are dysregulated causing malignant transformation. A wide variety of drugs are clinically used to treat non-cancerous diseases interfering with these malignancy-associated pathways. Repurposed drugs have key advantages: They already have approval for clinical use by national regulatory authorities. Moreover, they are for the most part inexpensive and their side effect and safety profiles are well characterized. In this work, we provide an overview on current repurposing strategies for the treatment of malignant glioma.


Asunto(s)
Antineoplásicos/uso terapéutico , Neoplasias Encefálicas/tratamiento farmacológico , Descubrimiento de Drogas , Reposicionamiento de Medicamentos/métodos , Glioma/tratamiento farmacológico , Animales , Humanos
8.
Nat Commun ; 11(1): 4977, 2020 10 05.
Artículo en Inglés | MEDLINE | ID: mdl-33020483

RESUMEN

Although thousands of breast cancer cells disseminate and home to bone marrow until primary surgery, usually less than a handful will succeed in establishing manifest metastases months to years later. To identify signals that support survival or outgrowth in patients, we profile rare bone marrow-derived disseminated cancer cells (DCCs) long before manifestation of metastasis and identify IL6/PI3K-signaling as candidate pathway for DCC activation. Surprisingly, and similar to mammary epithelial cells, DCCs lack membranous IL6 receptor expression and mechanistic dissection reveals IL6 trans-signaling to regulate a stem-like state of mammary epithelial cells via gp130. Responsiveness to IL6 trans-signals is found to be niche-dependent as bone marrow stromal and endosteal cells down-regulate gp130 in premalignant mammary epithelial cells as opposed to vascular niche cells. PIK3CA activation renders cells independent from IL6 trans-signaling. Consistent with a bottleneck function of microenvironmental DCC control, we find PIK3CA mutations highly associated with late-stage metastatic cells while being extremely rare in early DCCs. Our data suggest that the initial steps of metastasis formation are often not cancer cell-autonomous, but also depend on microenvironmental signals.


Asunto(s)
Interleucina-6/metabolismo , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/patología , Transducción de Señal , Médula Ósea/patología , Mama/citología , Neoplasias de la Mama/patología , Fosfatidilinositol 3-Quinasa Clase I/genética , Fosfatidilinositol 3-Quinasa Clase I/metabolismo , Receptor gp130 de Citocinas/metabolismo , Células Epiteliales/metabolismo , Células Epiteliales/patología , Femenino , Humanos , Interleucina-6/genética , Mutación , Metástasis de la Neoplasia/genética , Receptores de Interleucina-6/deficiencia , Receptores de Interleucina-6/metabolismo , Células del Estroma/metabolismo , Microambiente Tumoral
9.
Proc Natl Acad Sci U S A ; 117(6): 2894-2905, 2020 02 11.
Artículo en Inglés | MEDLINE | ID: mdl-31988137

RESUMEN

The Mediator kinase module regulates eukaryotic transcription by phosphorylating transcription-related targets and by modulating the association of Mediator and RNA polymerase II. The activity of its catalytic core, cyclin-dependent kinase 8 (CDK8), is controlled by Cyclin C and regulatory subunit MED12, with its deregulation contributing to numerous malignancies. Here, we combine in vitro biochemistry, cross-linking coupled to mass spectrometry, and in vivo studies to describe the binding location of the N-terminal segment of MED12 on the CDK8/Cyclin C complex and to gain mechanistic insights into the activation of CDK8 by MED12. Our data demonstrate that the N-terminal portion of MED12 wraps around CDK8, whereby it positions an "activation helix" close to the T-loop of CDK8 for its activation. Intriguingly, mutations in the activation helix that are frequently found in cancers do not diminish the affinity of MED12 for CDK8, yet likely alter the exact positioning of the activation helix. Furthermore, we find the transcriptome-wide gene-expression changes in human cells that result from a mutation in the MED12 activation helix to correlate with deregulated genes in breast and colon cancer. Finally, functional assays in the presence of kinase inhibitors reveal that binding of MED12 remodels the active site of CDK8 and thereby precludes the inhibition of ternary CDK8 complexes by type II kinase inhibitors. Taken together, our results not only allow us to propose a revised model of how CDK8 activity is regulated by MED12, but also offer a path forward in developing small molecules that target CDK8 in its MED12-bound form.


Asunto(s)
Quinasa 8 Dependiente de Ciclina/metabolismo , Complejo Mediador/metabolismo , Dominio Catalítico , Ciclina C/genética , Ciclina C/metabolismo , Quinasa 8 Dependiente de Ciclina/química , Quinasa 8 Dependiente de Ciclina/genética , Activación Enzimática , Humanos , Complejo Mediador/genética , Unión Proteica , Conformación Proteica en Hélice alfa , Dominios Proteicos
10.
Neurochem Res ; 42(12): 3382-3389, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28852934

RESUMEN

The sulfone dapsone is an old antibiotic used for the treatment of mycobacterial and protozoal infections. We postulated before that dapsone might possess biological activity exceeding its anti-infectious properties and that it could potentially be repurposed for the treatment of glioma. To test this hypothesis, we treated established and primary cultured glioma cells with dapsone or several dapsone analogues which we previously synthesized (D2-D5) and determined effects on proliferation, anchorage-independent growth and migration. While dapsone and its synthetic analogues D2-D5 displayed only modest anti-proliferative activity, important neoplastic features such as anchorage-independent growth, clonogenic survival and directed migration were significantly inhibited by dapsone treatment. Moreover, dapsone analogues D3, D4 and D5 yielded even enhanced anti-glioma activity against different pro-neoplastic features. Overall these data suggest that dapsone provides activity against glioma which can be further enhanced by molecular modifications. These compounds could potentially serve as a therapeutic adjunct to the treatment of gliomas in a repurposing approach.


Asunto(s)
Antibacterianos/uso terapéutico , Dapsona/química , Dapsona/farmacología , Glioma/tratamiento farmacológico , Humanos , Interleucina-8/metabolismo , Leucotrieno B4/antagonistas & inhibidores , Receptores de Formil Péptido/efectos de los fármacos
11.
ACS Med Chem Lett ; 7(6): 595-600, 2016 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-27326333

RESUMEN

Using Sorafenib as a starting point, a series of potent and selective inhibitors of CDK8 was developed. When cocrystallized with CDK8 and cyclin C, these compounds exhibit a Type-II (DMG-out) binding mode.

12.
ACS Med Chem Lett ; 7(3): 223-8, 2016 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-26985305

RESUMEN

Beginning with promiscuous COT inhibitors, which were found to inhibit CDK8, a series of 6-aza-benzothiophene containing compounds were developed into potent, selective CDK8 inhibitors. When cocrystallized with CDK8 and cyclin C, these compounds exhibit an unusual binding mode, making a single hydrogen bond to the hinge residue A100, a second to K252, and a key cation-π interaction with R356. Structure-based drug design resulted in tool compounds 13 and 32, which are highly potent, kinase selective, permeable compounds with a free fraction >2% and no measurable efflux. Despite these attractive properties, these compounds exhibit weak antiproliferative activity in the HCT-116 colon cancer cell line. Further examination of the activity of 32 in this cell line revealed that the compound reduced phosphorylation of the known CDK8 substrate STAT1 in a manner identical to a CDK8 knockout clone, illustrating the complex effects of inhibition of CDK8 kinase activity in proliferation in these cells.

13.
Rev. Ateneo Argent. Odontol ; 55(1): 65-67, 2016. ilus
Artículo en Español | LILACS | ID: lil-794294

RESUMEN

Estudios realizados en momias o en cuerpos momificados con técnicas convencionales y estudios de tomografía computada, revelaron patologíasmaxilofaciales tales como: atrición, pulpitis abscesos y enfermedad periodontal; además de otras enfermedades con mayor compromiso general, a saber: osteomielitis, enfermedad de Paget, defectos cráneomandibulares y traumas. Sin embargo, se observa un bajo porcentaje de caries. Para la continuidad de la vida en el más allá, revestía una importancia fundamental la conservación de loscuerpos en este mundo...


Asunto(s)
Humanos , Masculino , Adulto , Femenino , Recién Nacido , Enfermedades Maxilomandibulares , Imagenología Tridimensional/métodos , Momias , Paleontología/métodos , Tomografía Computarizada por Rayos X/métodos , Caries Dental , Osteítis Deformante , Osteomielitis , Tomografía Computarizada Espiral/métodos , Traumatismos de los Dientes
14.
Nature ; 526(7572): 273-276, 2015 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-26416749

RESUMEN

Super-enhancers (SEs), which are composed of large clusters of enhancers densely loaded with the Mediator complex, transcription factors and chromatin regulators, drive high expression of genes implicated in cell identity and disease, such as lineage-controlling transcription factors and oncogenes. BRD4 and CDK7 are positive regulators of SE-mediated transcription. By contrast, negative regulators of SE-associated genes have not been well described. Here we show that the Mediator-associated kinases cyclin-dependent kinase 8 (CDK8) and CDK19 restrain increased activation of key SE-associated genes in acute myeloid leukaemia (AML) cells. We report that the natural product cortistatin A (CA) selectively inhibits Mediator kinases, has anti-leukaemic activity in vitro and in vivo, and disproportionately induces upregulation of SE-associated genes in CA-sensitive AML cell lines but not in CA-insensitive cell lines. In AML cells, CA upregulated SE-associated genes with tumour suppressor and lineage-controlling functions, including the transcription factors CEBPA, IRF8, IRF1 and ETV6 (refs 6-8). The BRD4 inhibitor I-BET151 downregulated these SE-associated genes, yet also has anti-leukaemic activity. Individually increasing or decreasing the expression of these transcription factors suppressed AML cell growth, providing evidence that leukaemia cells are sensitive to the dosage of SE-associated genes. Our results demonstrate that Mediator kinases can negatively regulate SE-associated gene expression in specific cell types, and can be pharmacologically targeted as a therapeutic approach to AML.


Asunto(s)
Quinasa 8 Dependiente de Ciclina/antagonistas & inhibidores , Quinasas Ciclina-Dependientes/antagonistas & inhibidores , Elementos de Facilitación Genéticos/genética , Regulación Neoplásica de la Expresión Génica/genética , Genes Relacionados con las Neoplasias/genética , Leucemia Mieloide Aguda/enzimología , Leucemia Mieloide Aguda/genética , Animales , Proteínas de Ciclo Celular , División Celular/efectos de los fármacos , Línea Celular Tumoral , Linaje de la Célula/efectos de los fármacos , Linaje de la Célula/genética , Quinasa 8 Dependiente de Ciclina/metabolismo , Quinasas Ciclina-Dependientes/metabolismo , Progresión de la Enfermedad , Regulación hacia Abajo/efectos de los fármacos , Regulación hacia Abajo/genética , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Genes Supresores de Tumor/efectos de los fármacos , Compuestos Heterocíclicos de 4 o más Anillos/farmacología , Humanos , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/patología , Masculino , Ratones , Ratones Endogámicos , Ratones SCID , Proteínas Nucleares/antagonistas & inhibidores , Compuestos Policíclicos/farmacología , Factores de Transcripción/antagonistas & inhibidores , Factores de Transcripción/biosíntesis , Factores de Transcripción/genética , Regulación hacia Arriba/efectos de los fármacos , Regulación hacia Arriba/genética
15.
Proc Natl Acad Sci U S A ; 110(20): 8081-6, 2013 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-23630251

RESUMEN

In contrast with the very well explored concept of structure-activity relationship, similar studies are missing for the dependency between binding kinetics and compound structure of a protein ligand complex, the structure-kinetic relationship. Here, we present a structure-kinetic relationship study of the cyclin-dependent kinase 8 (CDK8)/cyclin C (CycC) complex. The scaffold moiety of the compounds is anchored in the kinase deep pocket and extended with diverse functional groups toward the hinge region and the front pocket. These variations can cause the compounds to change from fast to slow binding kinetics, resulting in an improved residence time. The flip of the DFG motif ("DMG" in CDK8) to the inactive DFG-out conformation appears to have relatively little influence on the velocity of binding. Hydrogen bonding with the kinase hinge region contributes to the residence time but has less impact than hydrophobic complementarities within the kinase front pocket.


Asunto(s)
Ciclina C/química , Quinasa 8 Dependiente de Ciclina/química , Secuencias de Aminoácidos , Dominio Catalítico , Cristalografía por Rayos X , Diseño de Fármacos , Humanos , Enlace de Hidrógeno , Cinética , Ligandos , Modelos Moleculares , Unión Proteica , Conformación Proteica , Sales (Química)/química , Temperatura , Factores de Tiempo
16.
BMC Res Notes ; 5: 100, 2012 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-22339896

RESUMEN

BACKGROUND: Infections with polyomavirus BK virus (BKV) are a common cause of renal dysfunction after renal transplantation and may also be harmful in surgical patients with shock. The aim of the present study was to determine the frequency of BKV viremia in critically ill surgical patients with septic or hemorrhagic shock, and, if viremia is detectable, whether viremia may be associated with renal dysfunction. FINDINGS: A total of 125 plasma samples from 44 critically ill surgical patients with septic or hemorrhagic shock were tested by real-time polymerase chain reaction (PCR) for BKV DNA during their stay on the intensive care unit (ICU). BKV viremia occurred in four patients, i.e. in three of the septic and in one of the hemorrhagic shock group. There was no association between viremia and renal dysfunction. All positive samples contained a low viral load (< 500 copies/ml). CONCLUSIONS: Since BK viremia was rarely found and with low viral load only in critically ill surgical patients with shock, it is very unlikely that BK viremia results in BK nephropathy later on.


Asunto(s)
Cuidados Críticos , ADN Viral/análisis , Infecciones por Polyomavirus/virología , Choque Hemorrágico/virología , Choque Séptico/virología , Viremia/virología , Adulto , Anciano , Anciano de 80 o más Años , Virus BK/fisiología , Femenino , Humanos , Unidades de Cuidados Intensivos , Riñón/patología , Riñón/virología , Masculino , Persona de Mediana Edad , Infecciones por Polyomavirus/complicaciones , Infecciones por Polyomavirus/cirugía , Estudios Prospectivos , Reacción en Cadena en Tiempo Real de la Polimerasa , Índice de Severidad de la Enfermedad , Choque Hemorrágico/complicaciones , Choque Hemorrágico/cirugía , Choque Séptico/complicaciones , Choque Séptico/cirugía , Carga Viral , Viremia/complicaciones , Viremia/cirugía
17.
Rev. Ateneo Argent. Odontol ; 50(1): 21-24, 2012. ilus
Artículo en Español | LILACS | ID: lil-679747

RESUMEN

Al encontrarse el odontólogo frente a diversas situaciones clínicas, el diagnóstico radiológico debe realizarlo generalmente con equipos para imágenes bidimensionales, sin contar con el equipamiento necesario para determinar un diagnósticode mayor certeza o precisión. Pueden entonces utilizarse medios que, aunque simples, nos aproximan a la realidad en la observación radiográfica. Entre ellos, se describen proyecciones intrabucales perpendiculares entre sí, y/o combinando las mismas con técnicas extrabucales que, ubicadas en dos de los tres planos del espacio, refuerzan la idea de altura, ancho y profundidad que pueda presentar un determinado objeto como por ej. un implante dentario. En la cirugía para la colocación de implantes dentales, durante el período intraoperatorio, es útil y hasta imprescindible la observación de la ubicación de éstos en por lo menos dos sentidos del espacio. El objetivo de este artículo es describir cómo emplear técnicas intraorales que r4esulten perpendiculares entre sí. De este modo, cuando no hya posibilidad de utilizar la tomografía en la práctica implantológica, podremos observar la posición de implantes y/o instrumentos intraoperatorios desde una perspectiva más completa para su localización. Estos métodos no han perdido su vigencia en el tiempo.


Asunto(s)
Humanos , Implantación Dental Endoósea , Procedimientos Quirúrgicos Preprotésicos Orales , Radiografía Dental/métodos , Equipo Dental , Película para Rayos X
18.
Rev. Ateneo Argent. Odontol ; 50(1): 21-24, 2012. ilus
Artículo en Español | BINACIS | ID: bin-128733

RESUMEN

Al encontrarse el odontólogo frente a diversas situaciones clínicas, el diagnóstico radiológico debe realizarlo generalmente con equipos para imágenes bidimensionales, sin contar con el equipamiento necesario para determinar un diagnósticode mayor certeza o precisión. Pueden entonces utilizarse medios que, aunque simples, nos aproximan a la realidad en la observación radiográfica. Entre ellos, se describen proyecciones intrabucales perpendiculares entre sí, y/o combinando las mismas con técnicas extrabucales que, ubicadas en dos de los tres planos del espacio, refuerzan la idea de altura, ancho y profundidad que pueda presentar un determinado objeto como por ej. un implante dentario. En la cirugía para la colocación de implantes dentales, durante el período intraoperatorio, es útil y hasta imprescindible la observación de la ubicación de éstos en por lo menos dos sentidos del espacio. El objetivo de este artículo es describir cómo emplear técnicas intraorales que r4esulten perpendiculares entre sí. De este modo, cuando no hya posibilidad de utilizar la tomografía en la práctica implantológica, podremos observar la posición de implantes y/o instrumentos intraoperatorios desde una perspectiva más completa para su localización. Estos métodos no han perdido su vigencia en el tiempo.(AU)


Asunto(s)
Humanos , Radiografía Dental/métodos , Implantación Dental Endoósea , Procedimientos Quirúrgicos Preprotésicos Orales , Película para Rayos X , Equipo Dental
19.
J Dairy Res ; 78(1): 38-42, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21118611

RESUMEN

Bacteriological analysis of milk samples from quarters of a dairy cow suffering from subclinical mastitis yielded two isolates of Staphylococcus aureus which gave a negative reaction in the standard coagulase test. Both isolates were also clumping factor and thermonuclease negative, and gave a negative reaction in the Staphaurex® test. The isolates were identified by using commercial biochemical systems, and by PCR analysis of different staphylococcal cell surface protein and exoprotein genes. Further molecular identification of the isolates, which included sequencing of the 16S rRNA gene and RT-PCR of coagulase (coa), clumping-factor (clfA) and thermonuclease (nuc) genes, was consistent with the diagnosis phenotypically 'coagulase-negative variant of Staph. aureus'. The fact that coagulase-negative Staph. aureus variants can occur in the context of intramammary infections in cattle may result in the incorrect diagnosis 'coagulase-negative staphylococci (CNS)' in routine mastitis diagnostic, at least in rare cases. To fully ensure correct species diagnosis, sequencing of the 16S rRNA gene and amplification of specific genes such as coa is necessary in these cases.


Asunto(s)
Coagulasa/análisis , Mastitis Bovina/microbiología , Leche/microbiología , Staphylococcus aureus/clasificación , Staphylococcus aureus/enzimología , Animales , Bovinos , Coagulasa/genética , ADN Bacteriano/análisis , ADN Bacteriano/química , Femenino , Nucleasa Microcócica/análisis , Nucleasa Microcócica/genética , ARN Ribosómico 16S/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Análisis de Secuencia de ADN , Infecciones Estafilocócicas/diagnóstico , Infecciones Estafilocócicas/microbiología , Staphylococcus aureus/genética
20.
Anal Bioanal Chem ; 399(3): 1051-9, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21103866

RESUMEN

The aim of this study was to develop and evaluate an enzyme immunoassay (EIA) for the cephalosporin antibiotic in milk, in combination with a new microbiological test system (brilliant black reduction test, BRT-P). Polyclonal antibodies against cefquinome were produced in rabbits, using cefquinome-keyhole limpet hemocyanine as the immunogen. These antibodies and a cefquinome-glucose oxidase conjugate were used in a competitive indirect EIA. The detection limit for cefquinome in milk was 1.5 ng ml(-1), recoveries were 80-128% at 4-40 ng ml(-1). Cross-reactivities with other cephalosporins/penicillins were all <1%. The EIA was used to determine cefquinome in incurred raw milk, the BRT-P (detection limit ≈ 20 ng ml(-1)) and a receptor assay (ßeta-s.t.a.r., detection limit ≈ 15 ng ml(-1)) were used in parallel. Five lactating cows, suffering from clinical mastitis, were treated with cefquinome by simultaneous intramammary and intramuscular injection. Cefquinome residues (maximum 10-27 µg ml(-1)) were most exclusively found in the udder quarter which was treated intramammary, residue levels in the other three quarters were low (<20 ng ml(-1)). Even in milk from intramammary-dosed quarters, residue levels fell below European Union maximum residue level (MRL, 20 µg kg(-1)) 2 days before the end of the withdrawal period. EIA, BRT-P, and ßeta-s.t.a.r. results showed acceptable agreement for milk samples, but the newly developed EIA is superior in aspects of sensitivity. In conclusion, this is the first one description of immunoassay and microbiological tests capable to determine cefquinome in milk at the MRL in incurred sample material.


Asunto(s)
Antibacterianos/análisis , Cefalosporinas/análisis , Glucosa Oxidasa/metabolismo , Técnicas para Inmunoenzimas/métodos , Mastitis Bovina/tratamiento farmacológico , Leche/química , Animales , Bovinos , Femenino , Glucosa Oxidasa/química , Hemocianinas/química , Estructura Molecular , Estereoisomerismo
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