Efficacy of an information system addressed to nursing staff for diminishing contaminated blood cultures: a blind clinical trial.

OBJECTIVE: Evaluate the efficacy of an information system addressed to nursing staff to lower the blood culture contamination rate. METHODS: A blind clinical trial was conducted at Internal Medicine and Emergency Departments during 2011. After following a reeducation program in BC extraction, participants were randomly selected in a 1:1 ratio. Every participant of the experimental group was informed of each worker's individual performance; whereas the control group was only informed of the global results. RESULTS: A total of 977 blood extractions were performed in 12 months. Blood culture contamination rate was 7.5%. This rate was higher in the Emergency Department than in Internal Medicine (10% vs. 3.8%; p=0.001). Factors associated with the higher risk of contamination were, in the univariate analysis, the extraction through a recently implanted blood route and the time of professional experience, while those associated with a lower risk were the extraction in Internal Medicine and through a butterfly needle. On multivariate analysis, extraction through a recently placed access was an independent risk factor for an increased contamination rate (OR 2.29; 95%CI 1.18-4.44, p=0.014), while individual information about the blood culture results (OR 0.11; 95%CI 0.023-0.57; p=0.008), and more than 9 years of professional experience were asso-ciated with fewer contaminations (OR 0.30; 95%CI 0.12-0.77; p=0.012). In the intervention group the contamination rate diminished by a 26 %. CONCLUSIONS: Drawing blood cultures through a recently taken peripheral venous access increased their risk of contamination. The intervention informing the nurse staff of the contamination rate is effective to decrease it.

Lesiones de mancha blanca en Ortodoncia. Conceptos actuals / White Spot Lesions in Dentistry. Current concepts

El desarrollo de lesiones de mancha blanca (WSLs) es un riesgo significativo asociado con el tratamiento de ortodoncia cuando la higiene oral es deficiente. Aparatos de ortodoncia fijos transforman los procedimientos de higiene oral convencionales más difíciles y aumentan el número de sitios de retención de placa. Si bien los valores de prevalencia son variados, los datos son suficientes para considerar la desmineralización como un problema importante, haciendo de la prevención durante el tratamiento uno de los mayores desafíos clínicos. El propósito de este trabajo es realizar una revisión actualizada de la literatura disponible respecto a la etiología, prevención y tratamiento de manchas blancas asociadas al tratamiento de ortodoncia con aparatología fija (AU)

The development of white spot lesions (WSLS) is a significant risk associated with orthodontic treatment when oral hygiene is poor. Fixed orthodontic appliances transform procedures of conventional oral hygiene more difficult and increase the number of sites plaque retention. While prevalence values vary, the data are sufficient to consider the demineralization as an important problem, making prevention during treatment one of the major clinical challenges. The purpose of this paper is review to date the available literature regarding the etiology, prevention and treatment of white spots associated with orthodontic treatment with dental braces (AU)

Antimicrobial activity of binary combinations of natural and synthetic phenolic antioxidants against Enterococcus faecalis.

This study investigated the antimicrobial activity of 3 natural (thymol, carvacrol, and gallic acid) and 2 synthetic [butylated hydroxyanisole (BHA) and octyl gallate] phenolic compounds, individually and in binary combinations, on 4 dairy isolates of Enterococcus faecalis with different virulence factors (ß-hemolytic, gelatinase, or trypsin activities; acquired resistance to erythromycin or tetracycline; and natural resistance to gentamicin). A checkerboard technique and a microdilution standardized method were used. All compounds individually tested exhibited antimicrobial activity against E. faecalis, with minimal inhibitory concentrations (MIC) ranging from 30 µg/mL (octyl gallate) to 3,150 µg/mL (gallic acid), although no significant differences were detected among strains to each phenolic compound. Carvacrol in combination with thymol or gallic acid, and gallic acid combined with octyl gallate showed partial synergistic inhibition of all E. faecalis strains. The most effective combinations were thymol+carvacrol and gallic acid+octyl gallate, as the MIC for each of these compounds was reduced by 67 to 75% compared with their respective individual MIC. These results highlight the possibility of using combinations of these phenolic compounds to inhibit the growth of potential virulent or spoilage E. faecalis strains by reducing the total amount of additives used in dairy foods.

Interoperable and standard e-Health solution over Bluetooth.

The new paradigm of e-Health demands open sensors and middleware components that permit transparent integration and end-to-end interoperability of new personal health devices. The use of standards seems to be the internationally adopted way to solve these problems. This paper presents the implementation of an end-to-end standards-based e-Health solution. This includes ISO/IEEE11073 standard for the interoperability of the medical devices in the patient environment and EN13606 standard for the interoperable exchange of the Electronic Healthcare Record. The design strictly fulfills all the technical features of the most recent versions of both standards. The implemented prototype has been tested in a laboratory environment to demonstrate its feasibility for its further transfer to the healthcare system.

Valoración de la Atención Continuada en un Centro de Salud Rural de la Comarca de la Vera en la provincia de Cáceres / Assessment of continuing care in a rural health centre in the Vera area of Caceres province, Spain

El objetivo fue determinar las características de la demanda asistencial en la atención continuada en una zona de salud rural de la Comarca de la Vera. Material y métodos. Estudio epidemiológico descriptivo y transversal, basado en la recogida de los datos que figuran en los libros de registro de cada una de las urgencias atendidas en el Centro de Salud de Villanueva de la Vera, desde el 1 de Enero de 2005 al 1 de Enero de 2006. Material y métodos. Se recogieron las siguientes variables: sexo, edad, hora, fecha, motivo de consulta, tipo de asistencia y derivación hospitalaria. Resultados. Se atendieron un total de 5.677 pacientes con una media de 473,08/mes y 15,6/día sin diferencia entre ambos sexos. Resultados. Un 93,1% se resolvieron en el centro de salud, mientras que un 6,8%, se derivaron al hospital de referencia siendo el primer motivo de traslado los problemas relacionados con el aparato locomotor. Resultados. La mayoría de la demanda corresponde a patologías no graves, por lo que nuestra labor asistencial, en los centros de atención primaria, debería estar enfocada hacia la educación para la salud influyendo positivamente en conocimientos, actitudes y conductas de la población. Conclusiones. El perfil de usuario que demanda atención continuada es el de una persona joven, trabajador activo que consulta por traumatismos y problemas respiratorios a la salida de sus centros de trabajo (AU)

The objective is to determine the characteristics of emergency care demand in the rural health area of Vera. Material and methods. A descriptive epidemiological, cross-sectional study, based on collecting the data contained in the records of each of the emergencies seen in the Villanueva Health Centre,Vera, from 1st January 2005 to 1st January 2006. We collected the following variables: gender, age, time, date, reason for consultation, and type of assistance and hospital referral. Results. A total of 5677 patients were seen, with an average of 15.6 per day (or 473/month) with no sex differences. Most, 93.1%, were resolved at the Health Centre, while 6.8%, were referred to Hospital, as the main cause was problems associated with musculoskeletal system movement. Results. Most of the demand is dealing with non-serious diseases, therefore care work in Primary Care Health Centres should be focused on health education impacting positively on knowledge, attitudes and behaviour of the population. Conclusions. The user profile that demand continuing care is that of a young person, active employee who complains of injuries and respiratory problems on leaving their workplaces (AU)

Factores modificantes del movimiento dentario ortodóncico / Modifiers factors of orthodontic tooth movement

El fenómeno de la remodelación ósea es fundamental tanto para ortodoncia como para la ortopedia dentofacial. Esta revisión clínica es sobre la relación de la actividad ósea desencadenada por las fuerzas ortodóncicas con diversos factores, como factores propios de los pacientes, moléculas producidas por tejidos enfermos, o drogas y nutrientes consumidas regularmente por los pacientes, los que pueden alcanzar los tejidos periodontales mecánicamente estresados por las fuerzas ortodóncicas a través de la circulación sanguínea, interactuando así con células blanco que producen la remodelación ósea necesaria para el movimiento dentario ortodóncico. El efecto combinado de estas fuerzas mecánicas con alguno de estos agentes pueden ser inhibitorio, aditivo o sinérgico. El objetivo de esta revisión es describir los mecanismos de acción y los efectos de algunas de las drogas y otros factores sobre la remodelación del tejido óseo y el movimiento dentario ortodóncico (AU)

Bone remodeling is fundamental to orthodontics and dentofacial orthopedics. This clinically oriented overview relate bone responses to orthodontic forces with many factors. Molecules produced in various diseased tissues, or drugs and nutrients consumed regularly by patients, can reach the mechanically stressed paradental tissues through the circulation, and interact with local target cells. The combined effect of mechanical forces and one or more of these agents may be inhibitory, additive or synergistic. The objective of this review is to outline the mechanisms of action and effects of some commonly used drugs and other factors on tissue remodeling and orthodontic tooth movement (AU)

Tres pacientes con esquizofrenia de inicio muy tardío / No disponible

Presentamos tres pacientes con esquizofrenia de iniciomuy tardío (por encima de los 60 años). El diagnósticoestá sometido a controversias por complejas razoneshistóricas y académicas. Ni CIE-10 ni DSM-IVrecogen esta entidad como una categoría independiente,tampoco existe un apartado geriátrico específico en lossistemas de clasificación citados. Se revisa el tema y serecogen las peculiaridades de esta forma de presentaciónde la enfermedad esquizofrénica

We present three patients with very-late-onset schizophrenia(over 60 years old). The diagnosis is matter ofcontroversy due to historical and complex academicreasons. Neither the CIE-10 nor the DSM-IV show thisentity as an independent category, not existing a geriatricsection either for the mentioned classification systems.The subject is reviewed and the peculiarities ofthis way of appearance of the schizophrenic illness areincluded

Implante hormonal subcutáneo: experiencia en una unidad clínica / Subdermal hormonal implant: an experience in a clinical unit

En España el número de Interrupciones Voluntarias de Embarazo (IVE) es elevado, así como la tasa de embarazos no deseados. en los últimos años ha variado notablemente el abanico de métodos anticonceptivos disponibles en nuestro país. Algunos de ellos, ya disponibles en otros países, se han introducido aquí, como es el caso del implante hormonal subcutáneo (IHS), considerado en la actualidad el anticonceptivo más eficaz, presentando además un excelente balance riesgo/beneficio. En el presente trabajo se analiza el perfil de las usuarias, así como los efectos adversos, grado de satisfacción e indicación del implante hormonal subcutáneo (IHS)

In Spain, the number of Volutary Interruptions of Pregnancy is high, as well as the rate of unintended pregnancies. Recently, the range of contraceptive methods available for Spaniards has widened considerably. Some of them, which were already available in other countries, have been introduced in Spain, such as the Subcutaneous Hormoonal Implant, regarded as the most effective contraceptive nowadays. Furthermore, it shows a great risk/benefit balance. The aim of this paper is the analysis of the users profile, the adverse effects, the degree of satisfaction and the methos used for women to carry the subdermal hormonal implant

Insuficiencia renal como primera manifestación del mieloma múltiple / Renal failure as first manifestation of multiple myeloma

El mieloma múltiple es el prototipo de gammapatía monoclonal maligna. Las manifestaciones se deben a la proliferación tumoral plasmocelular (lesiones esqueléticas, anemia, hipercalcemia e infiltración de diversos órganos y tejidos) y a la producción de la proteína monoclonal por parte de células mielomatosas (insuficiencia renal, predisposición a infecciones, síndrome de hiperviscosidad). Constituye la neoplasia de células plasmáticas más frecuente. La edad media se sitúa en 60-65 años. Los dolores óseos constituyen el síntoma más frecuente. En el 90% de los pacientes la velocidad de sedimentación globular (VSG) está elevada. Una cuarta parte de los pacientes presenta insuficiencia renal1

Multiple myeloma is the prototype of malignant monoclonal gammopathy. Manifestations are due to the plasmocellular tumor proliferation (skeletal lesions, anemia, hypercalcemia and infiltration of different organs and tissues) and to the production of monoclonal protein by myelomatous cells (renal failure, predisposition to infections, hyperviscosity syndrome). It is the most frequent plasma cell neoplasm. Mean age is around 60-65 years. Bone pains are the most frequent symptom. In 90% of the patients, the ERS is elevated. One fourth of the patients have renal failure1

Experience of a successful pediatric liver transplant program in Mexico.

Orthotopic liver transplantation (OLT) has been very difficult to develop in Mexico and for many years its occurrence was anecdotal. This report presents the results of a pediatric liver transplant program, analyzing the variables that affect outcomes. Between June 1998 and March 2004, 35 OLT were performed in 34 recipients including 80% cadaveric whole-organ grafts and 20% segmental grafts, with 11% from cadaveric and 9% from living donors. Most of the recipients were infants or toddlers weighing less than 15 kg. There was only 1 case of arterial thrombosis (2.8%); the graft was saved with a Kasai procedure. Biliary complications were present in 22% of cases, all resolved with reoperations. Posttransplant cytomegalovirus infection or reactivation (28%), acute rejection (25%), or posttransplant lymphoproliferative disorders (5.7%) were not a cause of graft or patient loss. Overall, 1- and 5-year patient survival rates are 77.1% and 74.2%, respectively; however, when the 1998-2000 cohort was compared with the 2001-2004 cohort, there was a significant difference in survival (P = .004). The 1-year patient survival for the later group is 91.6%. We performed the first successful living donor liver transplantation and the first simultaneous liver-kidney transplantation in a child in our country. Our results demonstrate that pediatric liver transplantation is a feasible undertaking in Mexico, with survival rates comparable to those of foreign centers.

Efficacy and safety of valgancyclovir as preemptive therapy for the prevention of cytomegalovirus disease in solid organ transplant recipients.

We prospectively followed 70 CMV-seropositive solid organ transplant recipients to evaluate the efficacy and safety of valganciclovir (VGCV) as preemptive therapy based on antigenemia test to prevent cytomegalovirus (CMV) disease. From December 2003 to May 2004, 12 of 70 (17%) asymptomatic patients who showed an antigenemia value > or =25 positive cells per 2 x 10(5) polymorphonuclear (PMN) were treated with VGCV (900 mg twice a day adjusted to renal function) until resolution of CMV antigenemia, a minimum of 14 days. No patient developed CMV disease during follow-up. Only one who showed an asymptomatic relapse of the antigenemia test > or =25 positive cells was successfully treated with a repeated course of VGCV. Mean duration of VGCV therapy was 18 days (range, 14 to 28). Antigenemia was negative in 7 of 12 (58%) patients after 14 days and negative in all patients 4 weeks after the administration of VGCV. No significant side effects were associated with the use of VGCV therapy. Preemptive VGCV therapy is safe and effective in the prevention of CMV disease in seropositive solid organ transplant recipients.

Brachytherapy for pediatric soft-tissue sarcoma.

PURPOSE: To review the use of brachytherapy (BRT) to treat soft-tissue sarcoma (STS) in pediatric patients at St. Jude Children's Research Hospital. METHODS AND MATERIALS: Thirty-one patients, median age 11 years (range 1-21 years) with Pediatric Oncology Group (POG) Grade 2-3 soft-tissue sarcoma (excluding rhabdomyosarcoma and Ewing's sarcoma) were treated with BRT initially (n = 27) or at the time of recurrence (n = 4) using I-125 or Ir-192 in a temporary (n = 29) or permanent implant (n = 2). Twelve patients were treated with BRT alone and the remaining 19 were treated with a combination of BRT and external beam irradiation (EBRT). The majority of patients had involved margins of resection (n = 20) and tumors less than 5 cm (n = 17). RESULTS: Twenty-seven patients were treated with BRT at the time of presentation. Among the 10 patients treated with BRT alone, one patient developed metastases (4 months) and died of metastatic disease (12 months after presentation); there were no local or regional failures among the remaining 9 patients. Among the 17 patients treated with a combination of BRT and EBRT, there was one local (17 months), two regional (both at 8 months), and 3 distant failures (12, 15, 66 months). The median survival for the surviving 25 patients was 34 months. Wound dehiscence, fibrosis/telangectasia, pigment changes, and cellulitis were the most common side effects. CONCLUSIONS: BRT is an excellent treatment option for pediatric patients with STS. Disease control may be achieved with a high rate of success when BRT is used alone or in combination with EBRT. BRT should be considered for patients with STS who require radiation therapy with the objective of reducing the dose to normal tissues and shortening the overall treatment time. Limb preservation, functional outcome, and toxicity assessment require careful assessment in a prospective study.

Effects of waterborne nitrite on phase I-II biotransformation in channel catfish (Ictalurus punctatus).

The effects of waterborne nitrite (3 mg/l NO2) on channel catfish were studied to evaluate changes in hematological parameters and phase I-II biotransformation in liver slices. Nitrite-exposed fish had significantly higher methemoglobin, blood and liver nitrite, and significantly lower pO2 than control fish. Total phase I-mediated metabolism of 7-ethoxycoumarin (EC) was not altered in nitrite-exposed fish compared with control fish (291 +/- 43 and 312 +/- 20 pmol/mg/h, respectively). However, phase II glucuronosyltransferase-mediated metabolism of 7-hydroxycoumarin (HC), both as a phase I metabolite of EC and as a parent substrate, was elevated in nitrite-exposed fish (204 +/- 17 and 1007 +/- 103 pmol/mg/h, respectively) as compared to control fish (149 +/- 14 and 735 +/- 87 pmol/mg/h) (P < 0.05). Sulfotransferase-mediated metabolism of HC (as a metabolite of EC and as a parent substrate) was not notably altered in nitrite-exposed fish (95 +/- 16 and 617 +/- 33 pmol/mg protein/h, respectively) as compared with control fish (118 +/- 24 and 575 +/- 55 pmol/mg/h, respectively). These studies indicate that in vivo nitrite exposure and associated changes in hematological parameters do not appear to affect hepatic phase I EC biotransformation in channel catfish. However, subtle but significant changes in phase II glucuronidation, but not sulfation activity, were observed. The mechanism of these alterations is unclear. However, the data suggest that environmentally realistic concentrations of nitrite may affect the dynamics of conjugative metabolism in exposed fish.

Malignant vascular tumors in young patients.

BACKGROUND: To the authors' knowledge there are few published series of malignant vascular tumors in patients age < or = 21 years. METHODS: The authors retrospectively documented the clinical presentation, pathology, treatment, and outcome of patients age < or = 21 years with malignant vascular tumors treated between 1970-1995 at Memorial Sloan-Kettering Cancer Center. The histologic sections were rereviewed to confirm the diagnosis. RESULTS: Four patients were identified with angiosarcoma and two with malignant hemangioendothelioma. Five patients were female and one was male; the median age at diagnosis was 11.8 years (range, 8 months-21 years). The tumor involved the skin in one patient, soft tissue in one patient, bone in two patients, and internal organs in two patients. One patient had associated diffuse angiomatosis and another had the Klippel-Trenaunay-Weber syndrome. This patient received prior radiation therapy to the primary site with the subsequent development of a vascular sarcoma. None of the patients had distant metastases at diagnosis. Resection was attempted in five patients and completed in four. Chemotherapy alone was given to three patients whereas radiation therapy alone and radiation plus chemotherapy were administered to one patient each. The median follow-up was 4.9 years (range, 1 month-12 years). There were three deaths from progressive disease and two deaths from locoregional recurrences. Reexcision and radiotherapy controlled one local recurrence. Another patient developed recurrence to regional lymph nodes and further dissemination. The primary tumor in all three survivors was excised completely whereas two of the three patients who died of progressive disease underwent an incomplete excision or biopsy alone. CONCLUSIONS: Malignant vascular tumors are rare in the first two decades of life and when they do occur are very aggressive. Complete resection is curative for patients with localized lesions.

Purification and characterization of an extracellular aspartate protease from Phycomyces blakesleeanus.

An acid protease has been found in the culture broth of Phycomyces blakesleeanus growing under standard conditions. It has been induced up to 70-fold with several complex growth media and the enzyme has been purified to homogeneity and characterized. The molecular mass of the native enzyme was estimated by gel filtration to be 40 kDa. The acid protease of Phycomyces migrated as a single band on sodium dodecyl sulfate-polyacrylamide gel electrophoresis, corresponding to a molecular mass of 35 kDa. The glycoprotein nature for the acid protease was deduced from its binding to a concanavalin A-Sepharose 4B column. The carbohydrate moiety is composed of mannose and rhamnose. Its amino acid composition was determined, and its isoelectric point was estimated to be 4.2, the optimum pH was 2.5 to 3, and the optimum temperature was 70 degrees C, using hemoglobin as a substrate. The enzyme showed thermal stability between 37 and 50 degrees C. The thermodynamic parameters for hemoglobin hydrolysis and thermal inactivation were calculated. With Lys-Pro-Ile-Glu-Phe-Phe(4-N02)-Arg-Leu as the substrate, the Km, kcat, and Vmax values were 8.78 microM, 1.25 s(-1), and 2.12 mumol min(-1) mg(-1), respectively. The protease was insensitive to phenylmethylsulfonyl fluoride, O-phenanthroline, N-ethylmaleimide, iodoacetamide, ethylenediaminetetraacetate, [ethyl-enebis(oxyethylenenitrilo)]tetraacetic acid, and trypsin inhibitor. However, pepstatin A established a strong competitive inhibition against it, with a K(i) value of 1.33 nM. The data suggest that this protease has properties of an aspartate-type proteinase.

Two NAD+-isocitrate dehydrogenase forms in Phycomyces blakesleeanus. Induction in response to acetate growth and characterization, kinetics, and regulation of both enzyme forms.

Two forms of NAD+-isocitrate dehydrogenase, named ICDH-1 and ICDH-2, have been identified and purified in Phycomyces blakesleeanus NRRL-1555(-). These enzymes forms may be separated by chromatography on DEAE-Sephacel. ICDH-2 induction was a response to the adaptation of Phycomyes growth on acetate as the carbon source. Both enzyme forms were octamers of 388 + or - 30 kDa with apparently identical subunits of 40.5 +/- 5 kDa, but they were distinguishable by their electrophoretic mobilities on polyacrylamide gel electrophoresis. Isoelectric pH values were 5.28 and 4.96 for ICDH-1 and ICDH-2, respectively. ICDH-2 was more stable to urea denaturation than ICDH-1. At pH 7.6, ICDH-1 showed a markedly sigmoidal kinetic behavior with respect to isocitrate. However, ICDH-1 and ICDH-2 showed hyperbolic kinetics with respect to NAD+. THe tribasic form of isocitrate (I3-) and its magnesium complex (MI-) are the true substrates for both enzyme forms. Kinetic data obtained with Mg2+ as a divalent cation for both enzyme forms are compatible with the kinetic mechanism proposed by Cohen and Colman (1974) [Eur. J. Biochem. 47, 35-45] but assuming some degree of interaction between binding sites for the active form of isocitrate. This report describes for the first time the existence of two forms of NAD+-isocitrate dehydrogenase in filamentous fungi. From the changes in activity levels for each form, during adaptation of Phycomyces to growth on acetate and taking into account the kinetic and regulatory properties of both enzyme forms, we discuss the role of ICDH-1 and ICDH-2 in the control of isocitrate flux in Phycomyces.

Evaluation of atrazine soil extraction methods for the determination by enzyme immunoassay and gas chromatography.

Four soil extraction methods were evaluated for the determination of atrazine and other s-triazines by ELISA and GC, using both field-treated and laboratory fortified samples. The most efficient recoveries for atrazine, simazine, and cyanazine from loam soil fortified at concentrations from 0.01 ppm to 1 ppm were obtained by mechanical wrist-action shaker (1 h) using methanol:water and solid phase extraction (SPE) cleanup (standard method). A handshaking extraction (1 min) with acetonitrile:water showed fairly good correlation with the standard extraction method and is suitable for field use with ELISA. Sonication using acetonitrile:water and SPE cleanup was the most efficient extraction method for the dealkylated metabolites (deisopropyl and deethyl atrazine) with recoveries higher than 60%. In general, supercritical fluid extraction (SFE) was as efficient as sonication and handshaking but was more variable. A guideline for validation of immunoassays and methods comparison is given. The sensitivity of the ELISA method was comparable to the GC and was both accurate and precise. Comparison of ELISA and GC determinations of 120 field soil samples and 40 laboratory spiked soil samples extracted with four different methods showed no false negatives or positives with excellent correlations and showed not significant differences (P > 0.05). An evaluation of the cost for GC and ELISA methods was also conducted.

Isolation, characterization and mapping of pyrimidine auxotrophs of Phycomyces blakesleeanus.

A total of seven pyrimidine auxotrophs of Phycomyces were isolated from among 5-fluoroorotate acid (5-FOA)-resistant mutants. They were classified by complementation into two groups. A representative mutant strain belonging to one group was deficient in orotate phosphoribosyl transferase (OPRTase; EC 2.4.2.10) activity; the mutant strain belonging to the second group was deficient in orotidine-5'-monophosphate decarboxylase (OMPdecase; EC 4.1.1.23). These mutants are defective in the genes pyrF and pyrG respectively. The results from random spore analysis, tetrad analysis, and gene-centromere distances showed that these two markers are located in linkage group VI, with pyrG being a proximal marker and pyrF a distal one.

Mitochondrial F1-ATPase moiety from Phycomyces blakesleeanus: purification, characterization, and kinetic studies.

Mitochondrial F1-ATPase was purified from the mycelium of Phycomyces blakesleeanus NRRL 1555(-) and its kinetic characteristics were studied. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the enzyme reveals five bands (alpha, beta, gamma, delta, and epsilon) characteristic of the F1 portion with apparent molecular weights of 60,000, 53,000, 31,000, 25,000, and 21,000, respectively. The molecular weight of the native F1-ATPase from Phycomyces blakesleeanus was in agreement with the stoichiometry alpha 3 beta 3 gamma delta epsilon. The MgATP complex is the true substrate for ATPase activity which has a Km value of 0.15 mM. High concentrations of free ATP or free Mg2+ ions inhibit the ATPase activity. ADP appears to act as a negative allosteric effector with regard to MgATP hydrolysis, with the apparent Vmax remaining unchanged.