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2.
Monaldi Arch Chest Dis ; 69(2): 50-4, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18837416

RESUMEN

BACKGROUND: Chronic Obstructive Pulmonary Disease (COPD) is a leading cause of morbidity and mortality worldwide, and its prevalence is rising. In Italy, respiratory diseases are the third most common cause of death. The aim of the study is to produce a patient information leaflet (PIL) designed to educate patients about COPD in accordance with the best recommendations based on evidence and guidelines for the production of good quality written information, and to evaluate the impact of this intervention on the patients' knowledge of COPD. METHODS: The study was conducted in the Department of Chest Diseases of the Cardarelli Hospital, Naples, Italy. A total of 166 patients admitted with a diagnosis of COPD participated in the study. Patients were asked to answer 10 multiple-choice questions compiled to assess their knowledge of the disease and then to read the leaflet. Two days later they were asked to complete the questionnaire again to assess their post-intervention knowledge. Analysis of the data was performed using SPSS version 15.0. RESULTS: After reading the leaflet, a statistically significant increase in the proportion of correct responses was noted (p < 0.001 by Wilcoxon signed rank test). Patients had retained the knowledge gained at the one year followup (p < 0.05 by Cochran's Q test). CONCLUSIONS: An educational intervention directed at adults with COPD had a positive impact on the patients' knowledge of COPD and this effect is long lasting.


Asunto(s)
Conocimientos, Actitudes y Práctica en Salud , Folletos , Educación del Paciente como Asunto , Enfermedad Pulmonar Obstructiva Crónica/terapia , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Relaciones Médico-Paciente
3.
Cancer Res ; 47(16): 4287-92, 1987 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-3607763

RESUMEN

Estrogen-binding proteins have been characterized in variants of the MTW-9B rat mammary tumor in an attempt to determine the functional significance of the low affinity cytosolic estrogen binder. In vivo selection of tumor variants was carried out by transplant of the tumor into intact and castrated male and female Wistar-Furth rats for four or five successive transplant generations. Tumors that developed in each of the four lines were taken for retransplant into intact and castrated male and female rats and all recipient tumor groups were compared for high and low affinity estrogen-binding proteins using isoelectric focusing analysis. No alterations in the isoelectric focusing profiles were observed in tumors that developed after repeated passage in ovariectomized female or castrated male rats when compared to the profile of the estrogen-binding proteins of the parent tumor carried routinely in intact female rats. However, a tumor variant containing only the low affinity, more basic estrogen-binding protein resulted from repeated passage of the MTW-9B mammary tumor in male rats. The high affinity estrogen receptor was absent in this variant and could not be induced by retransplant of the tumor into intact female hosts. Growth of the parent tumor and each of the variants was shown to be ovarian independent, suggesting that the presence of the low affinity estrogen-binding protein is not predictive of estrogen responsiveness. This suggestion is further supported by the observation that estrogen-stimulated progesterone receptor synthesis could be demonstrated in the parent tumor which demonstrated both binders, but not in the tumor variant developed in male rats which contained only the low affinity estrogen-binding protein. Progesterone receptor synthesis in this latter tumor appeared to be constitutive. Studies are continuing in an attempt to identify a role for the cytosolic low affinity estrogen-binding protein.


Asunto(s)
Proteínas Portadoras/análisis , Neoplasias Mamarias Experimentales/análisis , Animales , Unión Competitiva , Proteínas Portadoras/fisiología , Castración , Femenino , Focalización Isoeléctrica , Masculino , Neoplasias Mamarias Experimentales/patología , Ratas , Ratas Endogámicas , Receptores de Estrógenos/análisis , Receptores de Progesterona/análisis
4.
Biochim Biophys Acta ; 992(3): 362-8, 1989 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-2775791

RESUMEN

Most commonly used surfactants were found to be inhibitors of partially purified rat brain protein kinase C at or above their critical micellar concentrations (CMC). These include sodium lauryl sulfate, deoxycholate, octyl glucoside, dodecyl trimethylammonium bromide, linear alkylbenzene sulfonate and Triton X-100. Several detergents, including the nonionic surfactants digitonin and Neodol-12 (ethoxylated alcohol), did not inhibit protein kinase C activity, even at concentrations greater than their CMC, while the anionic surfactant, AEOS-12 (ethoxylated alcohol sulfate), inhibited enzyme activity only slightly (less than 8%). Since these latter surfactants have little or no inhibitory effect on protein kinase C, they may be of value in solubilizing cells and tissues for the determination of enzyme activity in crude extracts. Among the detergents tested, sodium lauryl sulfate and linear alkylbenzene sulfonate significantly stimulated protein kinase C activity in the absence of phosphatidylserine and calcium. This was found to be dependent on the presence of histone in the protein kinase C assay. These detergents failed to stimulate protein kinase C activity when endogenous proteins in the partially purified rat brain extracts were used as the substrate. Our results indicate that activity of protein kinase C can be modified by the conditions of the assay and by the detergents used to extract the enzyme.


Asunto(s)
Alcoholes/farmacología , Encéfalo/enzimología , Proteína Quinasa C/metabolismo , Tensoactivos/farmacología , Animales , Membrana Celular/enzimología , Citosol/enzimología , Femenino , Células HeLa/enzimología , Micelas , Peso Molecular , Fosfoproteínas/aislamiento & purificación , Fosforilación , Proteína Quinasa C/antagonistas & inhibidores , Proteína Quinasa C/aislamiento & purificación , Ratas , Ratas Endogámicas , Relación Estructura-Actividad
5.
Endocrinology ; 121(4): 1288-98, 1987 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-3653028

RESUMEN

A two-component estrogen (E2)-binding system has been characterized in the E2-independent MTW-9B rat mammary tumor by Scatchard analysis, sucrose gradient analysis, and isoelectric focusing. One cytosol receptor protein (type I) conforms to the classical estrogen receptor with a high affinity (Kd = 0.45 nM) for E2 and limited binding capacity [maximum binding (Bmax) = 53 fmol/mg protein]. The second component (type II) demonstrates a high number of sites (Bmax = 164 fmol/mg protein) and low E2-binding affinity (Kd = 22.3 nM). The type I and type II E2-binding components were shown to sediment on sucrose gradients at 9.6S and 4.5S, respectively, and to focus at isoelectric points of 6.6 and 8.0, respectively. The addition of 0.4 M KCl to the homogenization buffer converted the high affinity receptor species to a form that cosedimented and cofocused with the low affinity E2-binding protein. When tumors were grown in intact male rats, the ratio of the type II to the type I protein, as assessed by sucrose gradient analysis, increased 4.5-fold relative to that in tumors from intact females. Concomitantly, the Kd values of the type I and type II proteins were increased 9- and 2-fold, respectively, and the Bmax of the type I protein was decreased. No changes in the ratios of the E2-binding proteins were observed in tumors grown in ovariectomized female or castrated male rats; however, the Kd for both proteins was increased in tumors from the latter group. Relative to that in intact females, tumor growth was retarded in intact male rats, but was unaffected by ovariectomy or castration. These studies demonstrate that the presence of the low affinity E2-binding protein does not necessarily predict E2 responsiveness. While the role of the type II cytosolic protein has not yet been established, it is possible that it could act as a reservoir for E2, which is required to activate specific biochemical functions such as progesterone receptor synthesis. Alternatively, it could be a nonactivated, perhaps norphosphorylated, form of the E2 receptor which binds E2 with only a very low affinity.


Asunto(s)
Proteínas Portadoras/metabolismo , Hormonas/fisiología , Neoplasias Mamarias Experimentales/metabolismo , Receptores de Estrógenos , Animales , Proteínas Portadoras/clasificación , Centrifugación por Gradiente de Densidad , Citosol/metabolismo , Femenino , Focalización Isoeléctrica , Masculino , Neoplasias Mamarias Experimentales/ultraestructura , Molibdeno/farmacología , Trasplante de Neoplasias , Cloruro de Potasio/farmacología , Ratas , Ratas Endogámicas WF
6.
Biochimie ; 81(7): 771-9, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10492025

RESUMEN

DNA topoisomerase II regulates the three-dimensional organisation of DNA and is the principal target of many important anticancer and antimicrobial agents. These drugs usually act on the DNA cleavage/religation steps of the catalytic cycle resulting in accumulation of covalent DNA-topoisomerase II complexes. We have studied the different steps of the catalytic cycle as a function of salt concentration, which is a classical way to evaluate the biochemical properties of proteins. The results show that the catalytic activity of topoisomerase II follows a bell-shaped curve with optimum between 100 and 225 mM KCl. No straight-forward correlation exists between DNA binding and catalytic activity. The highest levels of drug-induced covalent DNA-topoisomerase II complexes are observed between 100 and 150 mM KCl. Remarkably, at salt concentrations between 150 mM and 225 mM KCl, topoisomerase II is converted into a drug-resistant form with greatly reduced levels of drug-induced DNA-topoisomerase II complexes. This is due to efficient religation rather than to absence of DNA cleavage as witnessed by relaxation of the supercoiled DNA substrate. In the absence of DNA, ATP hydrolysis is strongest at low salt concentrations. Unexpectedly, the addition of DNA stimulates ATP hydrolysis at 100 and 150 mM KCl, but has little or no effect below 100 mM KCl in spite of strong non-covalent DNA binding at these salt concentrations. Therefore, DNA-stimulated ATP hydrolysis appears to be associated with covalent rather than non-covalent binding of DNA to topoisomerase II. Taken together, the results suggest that it is the DNA cleavage/religation steps that are most closely associated with the catalytic activities of topoisomerase II providing a unifying theme for the biological and pharmacological modulation of this enzyme.


Asunto(s)
ADN-Topoisomerasas de Tipo II/metabolismo , ADN/metabolismo , Adenosina Trifosfato/metabolismo , Catálisis , Hidrólisis , Concentración Osmolar , Unión Proteica
7.
Peptides ; 22(4): 677-83, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11311739

RESUMEN

Hypothalamic cultured neurons and astrocytes were used to investigate the cellular mechanisms underlying the oxytocin receptor-mediated downregulation through a possible involvement of protein kinase C (PKC). For this purpose, the effects of PKC activators, inhibitor and of OT on OT receptor binding activity were compared in both cultures. In neurons, phorbol-myristate-acetate (PMA), a potent PKC activator, increased the binding of an OT receptor antagonist whereas in astrocytes, a decrease was observed. Pre-treatment of the cells with bisindolylmaleimide (10(-4) M), a PKC inhibitor, prevented the PMA-induced up- and downregulation. In contrast, receptor downregulation resulting from treatment of both cells with OT (10(-9) M) was not affected by the PKC inhibitor. On the other hand, when PMA (10(-7) M) was tested along with OT (10(-9) M), a subsequent decrease in ligand binding was observed in astrocytes. In neurons, PMA attenuated the OT-induced downregulation. Structural analysis of neuron and astrocyte OT receptor mRNA by RT-PCR, subcloning and sequencing, demonstrated identical sequence to rat uterine receptor. In conclusion, these data suggest that activation of PKC has opposite effect on OT receptor binding activity in neurons and astrocytes but they do not support the involvement of PKC in the OT-induced downregulation.


Asunto(s)
Regulación hacia Abajo/efectos de los fármacos , Hipotálamo/efectos de los fármacos , Receptores de Oxitocina/metabolismo , Acetato de Tetradecanoilforbol/farmacología , Regulación hacia Arriba/efectos de los fármacos , Animales , Astrocitos/efectos de los fármacos , Astrocitos/metabolismo , Inhibidores Enzimáticos/farmacología , Femenino , Hipotálamo/citología , Hipotálamo/metabolismo , Radioisótopos de Yodo , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Oxitocina/farmacología , Unión Proteica , Proteína Quinasa C/antagonistas & inhibidores , Proteína Quinasa C/metabolismo , Ensayo de Unión Radioligante , Ratas
8.
FEMS Microbiol Lett ; 162(1): 61-8, 1998 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-9595664

RESUMEN

Two PCR primer sets for the nitrous oxide reductase gene (nosZ) were developed. The initial primers were based on three sequences in GenBank and used to amplify nosZ from continental shelf sediments and from two denitrifiers in culture, Thiosphaera pantotropha and Pseudomonas denitrificans. Three unique marine sediment nosZ genes were identified and sequenced. The marine nosZ genes were most closely related to the nosZ genes of Paracoccus denitrificans or to Rhizobium meliloti. Alignment of all nosZ sequences currently available (n = 10) facilitated redesign of the PCR primers. Three new primer sets which amplify 1100 bp, 900 bp and 250 bp regions of the nosZ gene were designed and tested. The new primers robustly amplified nosZ fragments from samples in which the initial nosZ primers were only marginally successful.


Asunto(s)
Cartilla de ADN , Genes Bacterianos/genética , Sedimentos Geológicos/microbiología , Oxidorreductasas/genética , Reacción en Cadena de la Polimerasa/métodos , Secuencia de Aminoácidos , Secuencia de Bases , Clonación Molecular , ADN Bacteriano/análisis , ADN Bacteriano/genética , Bacterias Aerobias Gramnegativas/genética , Datos de Secuencia Molecular , Filogenia , Alineación de Secuencia , Análisis de Secuencia de ADN
9.
Cancer Genet Cytogenet ; 37(2): 263-8, 1989 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2702625

RESUMEN

Cytogenetic specimens were obtained from bone marrow 24-hour cultured cells in 22 patients with acute promyelocytic leukemia, including six with microgranular variant. A t(15;17) was identified in 10-100% of metaphase cells from 13 patients. We have found no correlation between complete remission percentage and karyotype. Our data suggest that each laboratory, as far as M3 and M3V are concerned, must study its own culture time as it relates to numerous parameters involving tumoral cell kinetics.


Asunto(s)
Cromosomas Humanos Par 15 , Cromosomas Humanos Par 17 , Leucemia Promielocítica Aguda/genética , Translocación Genética , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad
10.
Int J Artif Organs ; 22(10): 701-9, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10585135

RESUMEN

Aim of the study was to evaluate treatment efficacy and safety of a scaled-up version of our porcine hepatocytes based BAL system in pigs with complete liver ischemia (LIS). Thirty-one pigs underwent total devascularization of the liver (LIS) by termino-lateral porta-caval shunts and sutures around the bile duct, the common hepatic and gastroduodenal arteries and their accessory branches. The hepato-duodenal ligament was completely transected. Four experimental groups were studied: the first control group (LIS Control, n = 10) received glucose infusion only, the second control group (LIS Plasmapheresis, n = 8) was connected to a centrifugal plasma-separator with a bottle representing the bioreactor volume, the third control group (LIS Empty-BAL, n = 5) received BAL treatment without cells, and the treated group (LIS Cell-BAL, n = 8) was connected for a maximum period of 24 hours to our scaled-up BAL seeded with around 14 billion viable primary porcine hepatocytes. BAL treatment significantly prolonged life in large animals (approximately 35 kg) with complete LIS (Controls, mean +/- SEM: 33.1 +/- 3 h, Cell-BAL: 51.1 +/- 3.4 h; p = 0.001; longest survivor 63 h). In addition, blood ammonia and total bilirubin levels decreased significantly, indicating metabolic activity of porcine hepatocytes in the bioreactor. No significant differences were noticed among the three control groups, indicating that there was no device effect and that the plasmapheresis procedure was well tolerated. No important adverse effects were observed.


Asunto(s)
Fallo Hepático Agudo/terapia , Hígado Artificial , Hígado/citología , Animales , Biotransformación , Modelos Animales de Enfermedad , Pruebas de Función Hepática , Masculino , Plasmaféresis/métodos , Valores de Referencia , Tasa de Supervivencia , Porcinos , Resultado del Tratamiento
11.
Acta Chir Iugosl ; 57(3): 73-5, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21066988

RESUMEN

In the last years a wide range of new technique offers the possibility to have R0 resection in colorectal cancer. We report our experience about Single Port Laparoscopic Surgery (SPL) for not advanced right colon cancer and about pelvectomy with cilindric Abdominal Perineal Resection (APR) for advanced rectal cancer. SPL offer mainly cosmetic advantages but also quicker recovery. No touch technique with adequate surgical margin and lymphectomy were respected. Operative time of SPL was 85-115 minutes, the incision was 5 cm long. There were no complications. Length of hospital stay was 4-6 days. With advanced pelvic cancer, pelvic exenteration with en-bloc resection is indicated. Then we propose a case of a 55 years old woman with a pelvic recurrence from a metastatic rectal cancer involving the right obturator fossa, the vaginal stump, the right ureter. Modern surgical technique give us the chance to offer the most appropriate oncologic surgical treatment.


Asunto(s)
Neoplasias Colorrectales/cirugía , Neoplasias Colorrectales/patología , Femenino , Humanos , Laparoscopía , Persona de Mediana Edad , Procedimientos Quirúrgicos Mínimamente Invasivos , Exenteración Pélvica , Perineo/cirugía
12.
Cancer Chemother Pharmacol ; 66(2): 209-18, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20333385

RESUMEN

The standard treatment of CRC patients with hepatic metastases is systemic chemotherapy; however, 5-year survival is disappointingly poor despite recent advances. On the other hand, in patients who undergo immediate radical surgical resection of hepatic metastases, 5-year survival reaches 30-40%. Unfortunately, only 15-20% of patients with hepatic metastases are initially eligible for a radical surgical approach. The majority of patients undergoing liver resection relapse after surgery. For this reason, new onco-surgery approaches have been investigated in recent years and the addition of biological agents to chemotherapy, such as bevacizumab and cetuximab, and the improvements of surgical techniques have opened a new scenario in the management of colorectal liver metastases. Recently, the EORTC trial has demonstrated that perioperative chemotherapy (Folfox regimen) is feasible and improves progression-free survival in patients with resectable liver metastases. Chemotherapy and surgery can finally collaborate. In the unresectable setting, the association of chemotherapy with bevacizumab and cetuximab is particularly promising in improving resectability rate. In particular, K-RAS is a molecular response predictive factor that could be particularly useful in selecting the best treatment option in patients with unresectable liver disease.


Asunto(s)
Antineoplásicos/uso terapéutico , Neoplasias Colorrectales/patología , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/secundario , Quimioterapia Adyuvante , Ensayos Clínicos como Asunto , Terapia Combinada , Humanos , Neoplasias Hepáticas/cirugía , Cuidados Preoperatorios , Estudios Prospectivos , Estudios Retrospectivos
17.
Eur J Anaesthesiol ; 23(9): 801-5, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16780615

RESUMEN

BACKGROUND AND OBJECTIVE: Malignant hyperthermia is an inherited disorder of skeletal muscle characterized by muscle contracture and hypermetabolic crisis following exposure to halogenated anaesthetics and depolarizing muscle relaxants. We planned this follow-up to get more information about the safety of non-triggering anaesthesia in susceptible patients; the safety of the use of trigger agents in non-susceptible patients and any minor sequelae following the biopsy. METHODS: A questionnaire was sent to 244 patients tested for susceptibility between 1998 and 2004 enquiring about sequelae from the biopsy, subsequent experience with anaesthesia and difficulties encountered because of the investigation. RESULTS: Replies were received from 129 patients. Thirty-four complained about sequelae from the biopsy: 10 reported headache and nausea; 16 experienced pain and a lack of strength in the biopsed leg and 8 found the scar less than satisfactory. Ten patients found it difficult to find a diagnostic centre. Eighteen reported problems and/or delay when they had needed a subsequent anaesthetic. Fourteen patients found the anaesthesiologist reluctant to anaesthetize them and four experienced a delay. Forty-three patients received anaesthesia since their biopsy. Complete medical records were available for 24 anaesthetic exposures in 23 patients. No documented perioperative complications occurred. Only three non-susceptible patients received one trigger agent. CONCLUSIONS: It is safe to use trigger-free anaesthesia in susceptible patients. The difficulties encountered by patients to be anaesthetized and the management of the majority of non-susceptible patients during general anaesthesia show the need of more accurate educational programmes and methods for promoting patient-centred care.


Asunto(s)
Anestesiología/métodos , Susceptibilidad a Enfermedades , Hipertermia Maligna/diagnóstico , Adolescente , Adulto , Anestesia General , Biopsia , Niño , Estudios de Seguimiento , Humanos , Pierna/patología , Persona de Mediana Edad , Músculo Esquelético/patología , Encuestas y Cuestionarios , Factores de Tiempo
18.
Suppl Tumori ; 4(3): S209, 2005.
Artículo en Italiano | MEDLINE | ID: mdl-16437993

RESUMEN

Uterine leiomyosarcomas carry a dismail prognosis. Diagnosis is often an unexpected pathology discovery after hysterectomy for fibroma. Prognosis depends on the degree of locoregional extension and thus on early diagnosis. Extended surgery in case of relapse is sometimes the only possible approach for symptoms control and improvement of quality of life. A case of massive involvement of the abdomen by a relapsed uterine leiomyosarcoma treated by extreme surgery is here presented.


Asunto(s)
Neoplasias Abdominales/cirugía , Leiomiosarcoma/cirugía , Neoplasias Primarias Secundarias/cirugía , Terapia Recuperativa , Neoplasias Uterinas/cirugía , Adulto , Femenino , Humanos
19.
Appl Environ Microbiol ; 66(5): 1980-6, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-10788370

RESUMEN

Although it is widely believed that horizontal patchiness exists in microbial sediment communities, determining the extent of variability or the particular members of the bacterial community which account for the observed differences among sites at various scales has not been routinely demonstrated. In this study, horizontal heterogeneity was examined in time and space for denitrifying bacteria in continental shelf sediments off Tuckerton, N.J., at the Rutgers University Long-Term Ecosystem Observatory (LEO-15). Characterization of the denitrifying community was done using PCR amplification of the nitrous oxide reductase (nosZ) gene combined with terminal restriction fragment length polymorphism analysis. Spatial scales from centimeters to kilometers were examined, while temporal variation was assayed over the course of 1995 to 1996. Sorenson's indices (pairwise similarity values) were calculated to permit comparison between samples. The similarities of benthic denitrifiers ranged from 0.80 to 0.85 for centimeter scale comparisons, from 0.52 to 0.79 for meter level comparisons, and from 0.23 to 0.53 for kilometer scale comparisons. Sorenson's indices for temporal comparisons varied from 0.12 to 0.74. A cluster analysis of the similarity values indicated that the composition of the denitrifier assemblages varied most significantly at the kilometer scale and between seasons at individual stations. Specific nosZ genes were identified which varied at centimeter, meter, or kilometer scales and may be associated with variability in meio- or macrofaunal abundance (centimeter scale), bottom topography (meter scale), or sediment characteristics (kilometer scale).


Asunto(s)
Sedimentos Geológicos/microbiología , Bacilos y Cocos Aerobios Gramnegativos/clasificación , Oxidorreductasas/genética , Polimorfismo de Longitud del Fragmento de Restricción , Agua de Mar/microbiología , Análisis por Conglomerados , Ecosistema , Bacilos y Cocos Aerobios Gramnegativos/genética , Bacilos y Cocos Aerobios Gramnegativos/aislamiento & purificación , New Jersey , Filogenia
20.
Appl Environ Microbiol ; 65(4): 1681-7, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10103268

RESUMEN

Diversity of the nitrous oxide reductase (nosZ) gene was examined in sediments obtained from the Atlantic Ocean and Pacific Ocean continental shelves. Approximately 1,100 bp of the nosZ gene were amplified via PCR, using nosZ gene-specific primers. Thirty-seven unique copies of the nosZ gene from these marine environments were characterized, increasing the nosZ sequence database fourfold. The average DNA similarity for comparisons between all 49 variants of the nosZ gene was 64% +/- 10%. Alignment of the derived amino acid sequences confirmed the conservation of important structural motifs. A highly conserved region is proposed as the copper binding, catalytic site (CuZ) of the mature protein. Phylogenetic analysis demonstrated three major clusters of nosZ genes, with little overlap between environmental and culture-based groups. Finally, the two non-culture-based gene clusters generally corresponded to sampling location, implying that denitrifier communities may be restricted geographically.


Asunto(s)
Bacterias/aislamiento & purificación , Variación Genética , Sedimentos Geológicos , Oxidorreductasas/genética , Microbiología del Agua , Secuencia de Aminoácidos , Océano Atlántico , Bacterias/genética , Datos de Secuencia Molecular , Océano Pacífico , Filogenia , Reacción en Cadena de la Polimerasa/métodos , Alineación de Secuencia , Análisis de Secuencia de ADN
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