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1.
Prog Urol ; 30(4): 198-204, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31983605

RESUMEN

PURPOSE: To evaluate the effect of alpha-blocker treatment prior to transrectal ultrasound-guided prostate biopsy (TRUS-Bx) on voiding functions, pain scores and health-related quality-of-life outcomes. MATERIALS AND METHODS: From January 2018 to April 2019, a total of 112 patients underwent TRUS-Bx due to elevated prostate-specific antigen (PSA) or abnormal digital rectal examination findings. Patients were divided into 2 groups depending on whether they received pharmacological treatment before biopsy. Group 1 consisted of patients with no alpha-blocker treatment prior to biopsy and Group 2 consisted of patients who received Tamsulosin for one week before biopsy continuing for one week after biopsy. Voiding function was evaluated three times using the validated International Prostate Symptom Score (IPSS) and uroflowmetry (maximal flow rate (Qmax) and residual volume (PVR)). The Turkish version of the Medical Outcomes Study Short Form 36-item Questionnaire (SF-36) was used to assess health-related quality of life. Pain scores were rated according to the Visual Analogue Scale (VAS) just after the biopsy procedure. RESULTS: Mean IPSS and Qmax on the post-biopsy 7 day were significantly in favor of Group 2 (P<0.001, P=0.004). Although post-biopsy day 7 PVR was similar between the groups, Δ1 PVR was significantly in favor of Group 2 (P=0.004). Mean VAS score was 2.7±2.3 for the Tamsulosin group and 4.2±2.2 for the control group (P=0.001). There was no significant difference between two groups according to baseline and postoperative 1st month SF-36 scores. CONCLUSION: Alpha-blocker therapy prior to TRUS-Bx is effective in preventing voiding dysfunction and biopsy-related pain in patients undergoing TRUS-Bx. LEVEL OF EVIDENCE: 2.


Asunto(s)
Antagonistas Adrenérgicos alfa/administración & dosificación , Biopsia Guiada por Imagen/métodos , Neoplasias de la Próstata/diagnóstico , Tamsulosina/administración & dosificación , Anciano , Humanos , Masculino , Persona de Mediana Edad , Dolor/etiología , Dimensión del Dolor , Estudios Prospectivos , Antígeno Prostático Específico/sangre , Calidad de Vida , Ultrasonografía Intervencional
2.
Connect Tissue Res ; 60(2): 200-208, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-29860899

RESUMEN

PURPOSE: This study aimed to assess Achilles tendon repair in rats following splenectomy to simulate patients with musculoskeletal system injury who had splenectomy after spleen injury, a situation often seen in orthopedics and traumatology practice. MATERIALS AND METHODS: The study included 32 male Sprague-Dawley rats (10 months old; average weight, 394.5 ± 28.3 g). The rats were fed with standard rodent food ad libitum at 22°C in a dark environment for 12 h. They were divided into two groups, namely the splenectomy (total splenectomy and Achilles tendon repair) and control groups (only Achilles tendon repair; n = 16). Four weeks after the surgery, the rats were euthanized, and their Achilles tendons were examined histopathologically, immunohistochemically, and biomechanically. RESULTS: In the splenectomy group, proinflammatory cytokines, such as interleukin-1ß, tumor necrosis factor-α, and interferon-γ, showed significantly lower values than those in the control group (p ˂0.01); moreover, the levels of anti-inflammatory cytokines like vascular endothelial growth factor, transforming growth factor-ß1, interleukin-2, interleukin-10, and hepatocyte growth factor were significantly higher than in the control group (p ˂ 0.001). The average ultimate tensile strengths were 2.58 ± 0.5 in the splenectomy and 2.78 ± 0.3 in the control group (p = 0.043). The average εUTS values were 0.33 ± 0.5 in the splenectomy and 0.44 ± 0.1 in the control group (p = 0.021). CONCLUSION: Splenectomy may positively influence Achilles tendon healing through modification of the proinflammatory/anti-inflammatory ratio in favor of anti-inflammatory cytokines by causing a decrease in spleen-originated inflammatory cells.


Asunto(s)
Tendón Calcáneo/patología , Tendón Calcáneo/fisiopatología , Esplenectomía , Cicatrización de Heridas , Animales , Fenómenos Biomecánicos , Citocinas/metabolismo , Inmunohistoquímica , Masculino , Ratas Sprague-Dawley
4.
Cell Mol Life Sci ; 66(6): 968-80, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19153659

RESUMEN

The genomic integrity of all living organisms is constantly jeopardized by physical [e.g. ultraviolet (UV) light, ionizing radiation] and chemical (e.g. environmental pollutants, endogenously produced reactive metabolites) agents that damage the DNA. To overcome the deleterious effects of DNA lesions, nature evolved a number of complex multi-protein repair processes with broad, partially overlapping substrate specificity. In marked contrast, cells may use very simple repair systems, referred to as direct DNA damage reversal, that rely on a single protein, remove lesions in a basically error-free manner, show high substrate specificity, and do not involve incision of the sugar-phosphate backbone or base excision. This concise review deals with two types of direct DNA damage reversal: (i) the repair of alkylating damage by alkyltransferases and dioxygenases, and (ii) the repair of UV-induced damage by spore photoproduct lyases and photolyases. (Part of a Multi-author Review).


Asunto(s)
Daño del ADN , Reparación del ADN , Modelos Moleculares , Transferasas Alquil y Aril/química , Transferasas Alquil y Aril/genética , Transferasas Alquil y Aril/metabolismo , Alquilantes/toxicidad , Animales , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Desoxirribodipirimidina Fotoliasa/química , Desoxirribodipirimidina Fotoliasa/genética , Desoxirribodipirimidina Fotoliasa/metabolismo , Dioxigenasas/química , Dioxigenasas/genética , Dioxigenasas/metabolismo , Filogenia , Rayos Ultravioleta/efectos adversos
5.
Mol Cell Biol ; 18(6): 3182-90, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9584159

RESUMEN

Cells from complementation groups A through G of the heritable sun-sensitive disorder xeroderma pigmentosum (XP) show defects in nucleotide excision repair of damaged DNA. Proteins representing groups A, B, C, D, F, and G are subunits of the core recognition and incision machinery of repair. XP group E (XP-E) is the mildest form of the disorder, and cells generally show about 50% of the normal repair level. We investigated two protein factors previously implicated in the XP-E defect, UV-damaged DNA binding protein (UV-DDB) and replication protein A (RPA). Three newly identified XP-E cell lines (XP23PV, XP25PV, and a line formerly classified as an XP variant) were defective in UV-DDB binding activity but had levels of RPA in the normal range. The XP-E cell extracts did not display a significant nucleotide excision repair defect in vitro, with either UV-irradiated DNA or a uniquely placed cisplatin lesion used as a substrate. Purified UV-DDB protein did not stimulate repair of naked DNA by DDB- XP-E cell extracts, but microinjection of the protein into DDB- XP-E cells could partially correct the repair defect. RPA stimulated repair in normal, XP-E, or complemented extracts from other XP groups, and so the effect of RPA was not specific for XP-E cell extracts. These data strengthen the connection between XP-E and UV-DDB. Coupled with previous results, the findings suggest that UV-DDB has a role in the repair of DNA in chromatin.


Asunto(s)
Cromatina/metabolismo , Daño del ADN , Reparación del ADN , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Xerodermia Pigmentosa/genética , Células Cultivadas , Proteínas de Unión al ADN/administración & dosificación , Proteínas de Unión al ADN/farmacología , Humanos , Microinyecciones , Proteína de Replicación A , Piel/metabolismo , Piel/efectos de la radiación , Rayos Ultravioleta
6.
Mol Cell Biol ; 17(12): 6924-31, 1997 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9372924

RESUMEN

XPC-hHR23B protein complex is specifically involved in nucleotide excision repair (NER) of DNA lesions on transcriptionally inactive sequences as well as the nontranscribed strand of active genes. Here we demonstrate that not only highly purified recombinant hHR23B (rhHR23B) but also a second human homolog of the Saccharomyces cerevisiae Rad23 repair protein, hHR23A, stimulates the in vitro repair activity of recombinant human XPC (rhXPC), revealing functional redundancy between these human Rad23 homologs. Coprecipitation experiments with His-tagged rhHR23 as well as sedimentation velocity analysis showed that both rhHR23 proteins in vitro reconstitute a physical complex with rhXPC. Both complexes were more active than free rhXPC, indicating that complex assembly is required for the stimulation. rhHR23B was shown to stimulate an early stage of NER at or prior to incision. Furthermore, both rhHR23 proteins function in a defined NER system reconstituted with purified proteins, indicating direct involvement of hHR23 proteins in the DNA repair reaction via interaction with XPC.


Asunto(s)
Reparación del ADN/fisiología , Proteínas de Unión al ADN/metabolismo , Enzimas Reparadoras del ADN , Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/genética , Células HeLa , Humanos , Técnicas In Vitro , Sustancias Macromoleculares , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Fracciones Subcelulares/metabolismo , Xerodermia Pigmentosa/genética , Xerodermia Pigmentosa/metabolismo
7.
Nucleic Acids Res ; 27(19): 3875-80, 1999 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-10481027

RESUMEN

Specific and non-specific complexes of DNA and photolyase are visualised by atomic force microscopy. As a substrate for photolyase a 1150 bp DNA restriction fragment was UV-irradiated to produce damaged sites at random positions. Comparison with a 735 bp undamaged DNA fragment made it possible to separate populations of specific and non-specific photolyase complexes on the 1150 bp fragment, relieving the need for highly defined substrates. Thus it was possible to compare DNA bending for specific and non-specific interactions. Non-specific complexes show no significant bending but increased rigidity compared to naked DNA, whereas specific complexes show DNA bending of on average 36 degrees and higher flexibility. A model obtained by docking shows that photolyase can accommodate a 36 degrees bent DNA in the vicinity of the active site.


Asunto(s)
Proteínas de Unión al ADN/genética , ADN/ultraestructura , Desoxirribodipirimidina Fotoliasa/metabolismo , ADN/química , ADN/metabolismo , ADN Helicasas , Humanos , Microscopía de Fuerza Atómica , Modelos Moleculares , Conformación de Ácido Nucleico
8.
Nucleic Acids Res ; 28(22): 4506-13, 2000 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-11071939

RESUMEN

Nucleotide excision repair (NER) removes UV-induced photoproducts and numerous other DNA lesions in a highly conserved 'cut-and-paste' reaction that involves approximately 25 core components. In addition, several other proteins have been identified which are dispensable for NER in vitro but have an undefined role in vivo and may act at the interface of NER and other cellular processes. An intriguing example is the Saccharomyces cerevisiae Mms19 protein that has an unknown dual function in NER and RNA polymerase II transcription. Here we report the cloning and characterization of a human homolog, designated hMMS19, that encodes a 1030 amino acid protein with 26% identity and 51% similarity to S.cerevisiae Mms19p and with a strikingly similar size. The expression profile and nuclear location are consistent with a repair function. Co-immunoprecipitation experiments revealed that hMMS19 directly interacts with the XPB and XPD subunits of NER-transcription factor TFIIH. These findings extend the conservation of the NER apparatus and the link between NER and basal transcription and suggest that hMMS19 exerts its function in repair and transcription by interacting with the XPB and XPD helicases.


Asunto(s)
ADN Helicasas/metabolismo , Reparación del ADN/genética , Proteínas/genética , Proteínas de Saccharomyces cerevisiae , Factores Asociados con la Proteína de Unión a TATA , Factor de Transcripción TFIID , Factores de Transcripción TFII , Factores de Transcripción/metabolismo , Secuencia de Aminoácidos , Animales , Northern Blotting , Línea Celular , Mapeo Cromosómico , Cromosomas Humanos Par 10/genética , Clonación Molecular , ADN Complementario/química , ADN Complementario/genética , Proteínas de Unión al ADN/metabolismo , Femenino , Proteínas Fúngicas/genética , Expresión Génica , Regulación del Desarrollo de la Expresión Génica , Células HeLa , Humanos , Hibridación Fluorescente in Situ , Masculino , Datos de Secuencia Molecular , Filogenia , Unión Proteica , Proteínas/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Alineación de Secuencia , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido , Distribución Tisular , Factor de Transcripción TFIIH , Proteína de la Xerodermia Pigmentosa del Grupo D
9.
Cancer Res ; 55(19): 4325-32, 1995 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-7671243

RESUMEN

To understand the heterogeneity in genetic predisposition to skin cancer in different nucleotide excision repair-deficient human syndromes, we studied repair of cyclobutane pyrimidine dimers (CPDs) and of pyrimidine(6-4)pyrimidone (6-4PP) photoproducts in cells from trichothiodystrophy (TTD) patients. TTD is not associated with increased incidence of skin cancer, although 50% of the patients are photosensitive and carry a defect in the nucleotide excision repair pathway, similar to Xeroderma pigmentosum patients. However, in striking contrast to TTD, Xeroderma pigmentosum is highly prone to cancer. To address this apparent paradox, two types of studies were conducted: (a) reactivation of UV-irradiated plasmids harboring actively transcribed reporter genes, with or without photolyase treatment before transfection of SV40-transformed fibroblasts; and (b) the kinetics of removal of UV-induced CPDs and 6-4PPs in genomic DNA by immunoblot analysis using lesion-specific mAbs in SV40-transformed and untransformed fibroblasts representative of all genetic TTD complementation groups. Results showed that all cell lines from photosensitive TTD patients efficiently express Cat or luciferase genes in transfected plasmids carrying non-CPD lesions, including 6-4PP, and display wild-type or near-wild-type (50-70% in 3 cell lines) 6-4PP repair in the overall genome after immunoblot analysis. However, CPD lesions (the repair of which is defective in the overall genome) also block the expression of the reporter gene in transfected plasmids. Two cell lines from nonphotosensitive TTD patients showed wild-type levels of repair for both photoproducts in overall genome. A model on the lesion-specific repair in the context of the molecular defect in TTD is proposed. The implication of the defective CPD repair and efficient 6-4PP repair subpathways in cancer prevention in TTD patients is discussed.


Asunto(s)
Reparación del ADN , Cabello/anomalías , Dímeros de Pirimidina/metabolismo , Neoplasias Cutáneas/etiología , Xerodermia Pigmentosa/genética , Línea Celular , Cloranfenicol O-Acetiltransferasa/genética , Genes Reporteros , Humanos , Luciferasas/genética , Rayos Ultravioleta
10.
Cancer Res ; 50(6): 1905-10, 1990 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-2306742

RESUMEN

UV-induced thymine dimers (10 J/m2 of UV-C) were assayed in normal human and xeroderma pigmentosum (XP) fibroblasts with a monoclonal antibody against these dimers and quantitative fluorescence microscopy. In repair-proficient cells dimer-specific immunofluorescence gradually decreased with time, reaching about 25% of the initial fluorescence after 27 h. Rapid disappearance of dimers was observed in cells which had been microinjected with yeast photoreactivating enzyme prior to UV irradiation. This photoreactivation (PHR) was light dependent and (virtually) complete within 15 min of PHR illumination. In general, PHR of dimers strongly reduces UV-induced unscheduled DNA synthesis (UDS). However, when PHR was applied immediately after UV irradiation, UDS remained unchanged initially; the decrease set in only after 30 min. When PHR was performed 2 h after UV exposure, UDS dropped without delay. An explanation for this difference is preferential removal of some type(s) of nondimer lesions, e.g., (6-4) photoproducts, which is responsible for the PHR-resistant UDS immediately following UV irradiation. After the rapid removal of these photoproducts, the bulk of UDS is due to dimer repair. From the rapid effect of dimer removal by PHR on UDS it can be deduced that the excision of dimers up to the repair synthesis step takes considerably less than 30 min. Also in XP fibroblasts of various complementation groups the effect of PHR was investigated. The immunochemical dimer assay showed rapid PHR-dependent removal comparable to that in normal cells. However, the decrease of (residual) UDS due to PHR was absent (in XP-D) or much delayed (in XP-A and -E) compared to normal cells. This supports the idea that in these XP cells preferential repair of nondimer lesions does occur, but at a much lower rate.


Asunto(s)
Reparación del ADN , Replicación del ADN , Desoxirribodipirimidina Fotoliasa/metabolismo , Liasas/metabolismo , Dímeros de Pirimidina/metabolismo , Células Cultivadas , ADN/efectos de la radiación , Desoxirribodipirimidina Fotoliasa/administración & dosificación , Relación Dosis-Respuesta en la Radiación , Fibroblastos/metabolismo , Fibroblastos/efectos de la radiación , Humanos , Cinética , Microinyecciones , Valores de Referencia , Rayos Ultravioleta , Xerodermia Pigmentosa/metabolismo
11.
Biochim Biophys Acta ; 378(1): 54-63, 1975 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-804322

RESUMEN

A procedure is described for the isolation of a DNA photoreactivating enzyme from Streptomyces griseus. Application of chromatography on spherosil, ultraviolet-irradiated DNA-cellulose, DEAE-cellulose and single stranded-DNA-agarose resulted in a 22 000-fold purification with 46 percent recovery on the initial activity. According to polyacrylamide gel electrophoresis the final preparation was virtually homogeneous. The absorption spectrum of the enzyme exhibited a marked absorption band in the 400-460 nm region in addition to protein absorption.


Asunto(s)
Liasas/aislamiento & purificación , Streptomyces griseus/enzimología , Cromatografía de Afinidad , Cromatografía DEAE-Celulosa , Reparación del ADN , ADN Bacteriano , ADN de Cadena Simple , Electroforesis en Gel de Poliacrilamida , Luz , Espectrofotometría , Rayos Ultravioleta
12.
Biochim Biophys Acta ; 990(1): 80-6, 1989 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-2492438

RESUMEN

An 8-hydroxy-5-deazaflavin-dependent oxidoreductase was isolated from the actinomycete Streptomyces griseus and purified 590-fold with 72% overall yield. The enzyme catalyzes electron transfer between 8-hydroxy-5-deazaflavins and NADPH. It seems to be more specific than methanogenic oxidoreductase as it has an absolute requirement for both the 5-deazaflavin structure and the presence of an 8-hydroxy group in the substrate. A molecular weight of 42,000 was found with gel permeation chromatography, while SDS gel electrophoresis indicated the presence of two identical subunits. Maximal enzymatic activity was found at 0.32 M NaCl and pH 5.9 for reduction of 8-hydroxy-5-deazaflavin and pH 7.9 for the reverse reaction. From the kinetic constants it was estimated that the main function of this oxidoreductase is probably to provide cells with reduced 8-hydroxy-5-deazaflavin to be used in specific reduction reactions. These results indicate the occurrence of 8-hydroxy-5-deazaflavin-dependent electron transfer in microorganisms not belonging to the archaebacteria.


Asunto(s)
NADH NADPH Oxidorreductasas/metabolismo , Riboflavina/análogos & derivados , Streptomyces griseus/enzimología , Cromatografía , Cromatografía en Gel , Transporte de Electrón , Electroforesis en Gel de Poliacrilamida , Flavinas/metabolismo , Concentración de Iones de Hidrógeno , Cinética , Peso Molecular , NADH NADPH Oxidorreductasas/aislamiento & purificación , NADP/metabolismo , Fotoquímica , Especificidad de la Especie , Especificidad por Sustrato
13.
J Mol Biol ; 233(1): 167-9, 1993 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-8377184

RESUMEN

Photolyase (photoreactivating enzyme) from the cyanobacterium Anacystis nidulans was crystallized by the hanging drop vapor diffusion procedure using ammonium sulfate as a precipitant. The pale-yellow crystals were grown to a size of 0.4 mm in length and 0.1 mm in diameter. They belong to the tetragonal space group P4(1)2(1)2 or P4(3)2(1)2 with unit cell dimensions of a = b = 90.7 A and c = 135 A. Assuming that the asymmetric unit contains one molecule, the Vm value is calculated as 2.6 A3/dalton. The crystals are stable towards X-ray exposure and diffract beyond 2.5 A resolution.


Asunto(s)
Cianobacterias/enzimología , Desoxirribodipirimidina Fotoliasa/química , Cristalización , Difracción de Rayos X
14.
Ann Thorac Surg ; 59(2): 456-61, 1995 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-7847966

RESUMEN

The metabolic effects of combined antegrade/retrograde and antegrade cardioplegia on myocardial protection were evaluated and compared in 30 patients who underwent myocardial revascularization. All patients had three-vessel coronary artery disease, and the revascularization was done with exclusive use of arterial grafts (internal mammary artery, gastroepiploic artery). Myocardial protection consisted of oxygenated crystalloid cardioplegia, topical slushed ice, and moderate systemic hypothermia (34 degrees C). The patients were randomly separated into two groups: group A (n = 15), who received antegrade cardioplegia, and group A/R (n = 15), who received combined antegrade/retrograde cardioplegia. There was no significant difference between the two groups concerning preoperative and intraoperative data. After the first dose of cardioplegia, right ventricular temperature was significantly lower in group A/R (15 +/- 2 degrees versus 19 +/- 5 degrees C; p < 0.05), and there was no significant difference between the two groups in left ventricular temperature. Coronary sinus blood samples were obtained before bypass and 5, 10, and 15 minutes after reperfusion; there was no difference between the two groups concerning lactates, superoxide dismutase, and glutathione peroxidase. After reperfusion, malondialdehyde levels increased significantly in group A and there was no change in group A/R, with a significant difference between the two groups (at 10 minutes after reperfusion, 0.80 +/- 0.20 versus 0.53 +/- 0.16 mumol/L; p < 0.05). Right and left ventricular myocardial biopsies were performed before bypass and 15 minutes after reperfusion; there was no significant difference between the two groups concerning adenosine triphosphate and creatine phosphate myocardial concentrations.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Paro Cardíaco Inducido/métodos , Revascularización Miocárdica , Adenosina Trifosfato/metabolismo , Soluciones Cardiopléjicas , Creatina Quinasa/sangre , Femenino , Glutatión Peroxidasa/sangre , Humanos , Isoenzimas , Lactatos/sangre , Masculino , Malondialdehído/sangre , Persona de Mediana Edad , Reperfusión Miocárdica , Miocardio/metabolismo , Fosfocreatina/metabolismo , Superóxido Dismutasa/sangre
15.
Ann Thorac Surg ; 59(4): 955-60, 1995 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7695424

RESUMEN

From January 1990 to June 1994, 240 patients (mean age, 60 +/- 10 years) underwent myocardial revascularization with the exclusive use of in situ bilateral internal mammary and right gastroepiploic arteries. Left ventricular function was normal in 34% of patients, moderately impaired in 58.5%, and severely impaired in 7.5%. The mean number of distal anastomoses was 3.5 +/- 0.7 and the rate of complete myocardial revascularization was 80%. Early mortality was 0.4%, and complications occurred in 20 patients: myocardial infarction, 1.6%; intraaortic balloon pump, 0.8%; reoperation for bleeding, 0.8%; and mediastinitis, 0.4%. Early (15th postoperative day) angiographic control of grafts was performed in 51 patients; the rate of functional and patent anastomoses was 100% for internal mammary arteries and 96% for gastroepiploic arteries. Early functional results (3 +/- 1 postoperative months) were studied in 141 patients during exercise test with medical treatment: 99% were symptom-free and 14% had ischemic modification of electrocardiograms. A 2-year postoperative functional assessment without medical treatment was performed during exercise test in 66 patients: 98% were symptom-free and 26% had ischemic modification of electrocardiograms; during the same procedure, thallium myocardial scintigraphy was obtained in 50 patients and 18 patients had moderate ischemic defect on exercise. Ischemic modifications of electrocardiograms and defects seen on thallium scintigraphy were correlated significantly with incomplete revascularization (p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Músculos Abdominales/irrigación sanguínea , Revascularización Miocárdica/métodos , Adulto , Anciano , Anciano de 80 o más Años , Arterias/trasplante , Causas de Muerte , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Morbilidad , Isquemia Miocárdica/diagnóstico por imagen , Revascularización Miocárdica/mortalidad , Cintigrafía , Grado de Desobstrucción Vascular
16.
Ann Thorac Surg ; 58(6): 1721-8; discussion 1727-8, 1994 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7979743

RESUMEN

From January 1979 to December 1990, 397 consecutive patients (mean age, 55 +/- 11 years) underwent mitral valve replacement with the St. Jude Medical valve. Associated procedures performed were 174 multiple valve replacements, 24 coronary artery bypass graftings, 25 tricuspid repairs, and 13 left ventricular myectomies. The continuous intravenous administration of heparin was started on the first postoperative day and maintained until effective oral anticoagulation, started on the seventh day, was achieved (INR, 3 to 4.5). Follow-up consisted of 2,402 patient-years (pt-y) (mean, 6.1 +/- 0.2 years) and was 97% complete. The early (30-day) mortality was 3.5%; the 5-year and 10-year actuarial survivals were 86% +/- 4% and 73% +/- 6%, respectively. Survival was less in patients who had been in an advanced preoperative functional class (p = 0.02) and in those who underwent multiple valve replacements (p = 0.05). The 5-year and 10-year survivals in patients who underwent isolated mitral valve replacement and who were in preoperative New York Heart Association functional class II and III, were 90% +/- 5% and 82% +/- 7%, respectively. The early and late mortality and the incidence of deaths resulting from heart failure and sudden deaths were higher in patients who had undergone multiple valve replacements (p = 0.05). In terms of all deaths, 47% (36/77) were valve related (including 12 sudden deaths, 0.50%/pt-y). Thromboembolic complications occurred in 44 patients, and these were broken down as follows: embolism, 1.46%/pt-y, and valve thrombosis, 0.37%/pt-y.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Prótesis Valvulares Cardíacas/efectos adversos , Prótesis Valvulares Cardíacas/mortalidad , Tromboembolia/etiología , Tromboembolia/mortalidad , Adulto , Anciano , Anticoagulantes/uso terapéutico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Válvula Mitral , Tasa de Supervivencia , Factores de Tiempo , Resultado del Tratamiento
17.
Ann Thorac Surg ; 57(5): 1151-7, 1994 May.
Artículo en Inglés | MEDLINE | ID: mdl-8179378

RESUMEN

Between November 1989 and September 1990, a cardiomyoplasty procedure was performed in 12 male patients with a mean age of 59 years. All patients were in New York Heart Association class III. Reinforcement cardiomyoplasty was isolated in 4 patients and associated with a cardiac procedure in 8. There were no perioperative deaths. Failure of cardiomyoplasty occurred in 5 patients because of recurrence of disabling congestive heart failure: 3 patients died late, and 2 had heart transplantation. The actuarial survival rate was 83% at 1 year and 73% at 2 years. Hemodynamic studies were done preoperatively in all patients, at 6 months postoperatively in 11 patients, at 1 year in 8, and at 2 years in 7. At the 2-year follow-up, 6 of the 7 survivors who did not have transplantation were functionally improved with reduced medical treatment. The following indices improved significantly at the 2-year evaluation compared with baseline: exercise capacity (63 +/- 13 W versus 83 +/- 17 W); left ventricular (LV) end-diastolic pressure (20 +/- 7 mm Hg versus 11 +/- 5 mm Hg); and angiographic LV ejection fraction (0.25 +/- 0.09 versus 0.40 +/- 0.15). Pulmonary artery pressure, pulmonary capillary wedge pressure, and cardiac index remained unchanged. Four patients underwent beat-to-beat analysis of LV function at 2 years; during skeletal muscle stimulation, stroke volume increased by 7% to 35% and LV end-systolic pressure, by 5% to 9%. In the 5 patients with failed cardiomyoplasty, mean pulmonary artery pressure and LV end-diastolic volume were higher preoperatively than in the 7 survivors.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Circulación Asistida , Procedimientos Quirúrgicos Cardíacos , Insuficiencia Cardíaca/cirugía , Hemodinámica , Músculos/trasplante , Anciano , Insuficiencia Cardíaca/mortalidad , Insuficiencia Cardíaca/fisiopatología , Trasplante de Corazón , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Tasa de Supervivencia
18.
Photochem Photobiol ; 60(2): 125-33, 1994 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7938208

RESUMEN

A phr-gene from the filamentous fungus Neurospora crassa was overexpressed in Escherichia coli cells, yielding a biologically active photolyase. After purification till apparent homogeneity, the 66 kDa protein was found to contain equimolar amounts of 5,10-methenyltetrahydrofolic acid (MTHF) and FAD, classifying it as an MTHF-type photolyase. Compared to other MTHF photolyases the absorption maximum of Neurospora photolyase is shifted from ca 380 nm to 391 nm (epsilon = 34,800), while an additional shoulder is present at 465 nm. In dark-adapted enzyme the FAD chromophore is predominantly present in the oxidized form, in contrast with E. coli and Saccharomyces cerevisiae photolyase, which contain mainly semiquinone or fully reduced FAD, respectively. Preillumination or dithionite treatment converted oxidized FAD in Neurospora photolyase into the fully reduced form, with a concomitant shift of the absorption maximum from 391 to 396 nm and disappearance of the 465 nm shoulder. The action spectrum of photoreactivation coincides with the absorption spectrum of preilluminated (reduced) photolyase, extending the spectral region of MTHF-type photolyases from 380 till 396 nm. A quantum yield of 0.57 was obtained for the overall repair reaction. Comparison of spectral properties of FAD in Neurospora photolyase and the model compound lumiflavin points to an apolar microenvironment of photolyase-bound FAD. Neurospora photolyase has distinct advantages over E. coli photolyase as it is more stable and contains a full complement of chromophores.


Asunto(s)
Desoxirribodipirimidina Fotoliasa/química , Neurospora crassa/enzimología , Desoxirribodipirimidina Fotoliasa/genética , Escherichia coli/enzimología , Neurospora crassa/genética , Fotoquímica , Saccharomyces cerevisiae/enzimología , Espectrometría de Fluorescencia
19.
Photochem Photobiol ; 50(5): 633-7, 1989 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-2516329

RESUMEN

The Anacystis nidulans photolyase gene inserted in an expression vector plasmid was introduced into Escherichia coli cells and the production of Anacystis photolyase protein was confirmed by reaction with antibodies raised against photolyase purified from A. nidulans cells. The Anacystis photolyase functioned in photoreactivation repair defective E. coli cells. The E. coli transformants exhibited an action spectrum with a maximum around 380 nm similar to that of E. coli photolyase in contrast with the action spectrum of A. nidulans cells which has a maximum at 437 nm. These results indicate that the Anacystis photolyase produced in E. coli cells has enzymatic activity in spite of the apparent lack of its intrinsic 8-hydroxy-5-deazaflavin cofactor.


Asunto(s)
Cianobacterias/enzimología , Reparación del ADN , Desoxirribodipirimidina Fotoliasa/genética , Escherichia coli/enzimología , Expresión Génica , Liasas/genética , Secuencia de Bases , Clonación Molecular , Coenzimas , Cianobacterias/genética , Desoxirribodipirimidina Fotoliasa/metabolismo , Escherichia coli/genética , Immunoblotting , Datos de Secuencia Molecular , Mutación , Fotoquímica , Plásmidos , Regiones Promotoras Genéticas , Riboflavina/análogos & derivados , Riboflavina/análisis , Transformación Bacteriana
20.
Photochem Photobiol ; 69(1): 108-13, 1999 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10063806

RESUMEN

A gene encoding a 62.5 kDa homolog of Drosophila melanogaster photolyase was isolated. Purified recombinant protein contained a flavin adenine dinucleotide chromophore. The recombinant protein did not show photolyase activity for either cyclobutane pyrimidine dimers or 6-4 photoproducts in vitro as well as in vivo in Escherichia coli host cells, suggesting that the protein is not a DNA repair enzyme but a blue-light photoreceptor. Reverse transcription polymerase chain reaction analysis showed that the gene is more expressed in head than in body and that it is more expressed in antennae than in legs, wings and mouth appendages. In a phylogenetic tree of the photolyase family, the Drosophila photolyase homolog is located in a cluster containing 6-4 photolyases and mammalian photolyase homologs, which is only distantly related to the clade of higher plant blue-light photoreceptors. The mammalian photolyase homologs are more closely related to Drosophila 6-4 photolyase than to the Drosophila photolyase homolog, suggesting different roles of the photolyase homologs.


Asunto(s)
Desoxirribodipirimidina Fotoliasa/genética , Drosophila melanogaster/enzimología , Drosophila melanogaster/genética , Células Fotorreceptoras de Invertebrados/enzimología , Animales , Secuencia de Bases , Clonación Molecular , Cartilla de ADN/genética , Genes de Insecto , Fotobiología , Filogenia
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