RESUMEN
A number of bacteria and fungi are known to degrade tannins. In this study, the efficiency of the white-rot fungus, Bjerkandera adusta MUT 2295, was evaluated for the treatment of a synthetic solution prepared with tannic acid. Tests were performed in continuously fed, bench-scale, packed-bed reactors, operated under non-sterile conditions with biomass immobilized within PolyUrethane Foam cubes (PUFs). The main parameters monitored to evaluate the process efficiency were: soluble Chemical Oxygen Demand (sCOD), Total Organic Carbon (TOC) removal, and activities. of Tannase and Lignin Peroxidase. At the end of the process, additional parameters were evaluated, including the increase of fungal dry weight and the presence of ergosterol. The reactor was operative for 210 days, with maximum sCOD and TOC removal of 81% and 73%, respectively. The reduction of sCOD and TOC were positively correlated with the detection of Tannase and Lignin Peroxidase (LiP) activities. Increases in biomass within the PUF cubes was associated with increases in ergosterol concentrations. This study proved that the fungal-based system tested was efficient for the degradation of tannic acid over a period of time, and under non-sterile conditions.
Asunto(s)
Basidiomycota , Reactores Biológicos , Análisis de la Demanda Biológica de Oxígeno , Biomasa , TaninosRESUMEN
Loss of significant intestinal length from congenital anomaly or disease may lead to short bowel syndrome (SBS); intestinal failure may be partially offset by a gain in epithelial surface area, termed adaptation. Current in vivo models of SBS are costly and technically challenging. Operative times and survival rates have slowed extension to transgenic models. We created a new reproducible in vivo model of SBS in zebrafish, a tractable vertebrate model, to facilitate investigation of the mechanisms of intestinal adaptation. Proximal intestinal diversion at segment 1 (S1, equivalent to jejunum) was performed in adult male zebrafish. SBS fish emptied distal intestinal contents via stoma as in the human disease. After 2 wk, S1 was dilated compared with controls and villus ridges had increased complexity, contributing to greater villus epithelial perimeter. The number of intervillus pockets, the intestinal stem cell zone of the zebrafish increased and contained a higher number of bromodeoxyuridine (BrdU)-labeled cells after 2 wk of SBS. Egf receptor and a subset of its ligands, also drivers of adaptation, were upregulated in SBS fish. Igf has been reported as a driver of intestinal adaptation in other animal models, and SBS fish exposed to a pharmacological inhibitor of the Igf receptor failed to demonstrate signs of intestinal adaptation, such as increased inner epithelial perimeter and BrdU incorporation. We describe a technically feasible model of human SBS in the zebrafish, a faster and less expensive tool to investigate intestinal stem cell plasticity as well as the mechanisms that drive intestinal adaptation.
Asunto(s)
Adaptación Biológica/fisiología , Intestinos , Síndrome del Intestino Corto/metabolismo , Animales , Antimetabolitos/farmacología , Bromodesoxiuridina/farmacología , Proliferación Celular , Procedimientos Quirúrgicos del Sistema Digestivo/métodos , Modelos Animales de Enfermedad , Humanos , Factor I del Crecimiento Similar a la Insulina/metabolismo , Mucosa Intestinal/patología , Intestinos/patología , Intestinos/fisiopatología , Intestinos/cirugía , Masculino , Células Madre/fisiología , Pérdida de Peso , Pez Cebra , Proteínas de Pez Cebra/metabolismoRESUMEN
Clostridium thermocellum produces ethanol as one of its major end products from direct fermentation of cellulosic biomass. Therefore, it is viewed as an attractive model for the production of biofuels via consolidated bioprocessing. However, a better understanding of the metabolic pathways, along with their putative regulation, could lead to improved strategies for increasing the production of ethanol. In the absence of an annotated pyruvate kinase in the genome, alternate means of generating pyruvate have been sought. Previous proteomic and transcriptomic work detected high levels of a malate dehydrogenase and malic enzyme, which may be used as part of a malate shunt for the generation of pyruvate from phosphoenolpyruvate. The purification and characterization of the malate dehydrogenase and malic enzyme are described in order to elucidate their putative roles in malate shunt and their potential role in C. thermocellum metabolism. The malate dehydrogenase catalyzed the reduction of oxaloacetate to malate utilizing NADH or NADPH with a kcat of 45.8 s(-1) or 14.9 s(-1), respectively, resulting in a 12-fold increase in catalytic efficiency when using NADH over NADPH. The malic enzyme displayed reversible malate decarboxylation activity with a kcat of 520.8 s(-1). The malic enzyme used NADP(+) as a cofactor along with NH4 (+) and Mn(2+) as activators. Pyrophosphate was found to be a potent inhibitor of malic enzyme activity, with a Ki of 0.036 mM. We propose a putative regulatory mechanism of the malate shunt by pyrophosphate and NH4 (+) based on the characterization of the malate dehydrogenase and malic enzyme.
Asunto(s)
Clostridium thermocellum/metabolismo , Malato Deshidrogenasa/metabolismo , Malatos/metabolismo , Redes y Vías Metabólicas/genética , NADP Transhidrogenasas/metabolismo , Compuestos de Amonio/metabolismo , Celulosa/metabolismo , Clostridium thermocellum/enzimología , Clostridium thermocellum/genética , Coenzimas/metabolismo , Difosfatos/metabolismo , Etanol/metabolismo , Regulación Enzimológica de la Expresión Génica , Cinética , Malato Deshidrogenasa/genética , Malato Deshidrogenasa/aislamiento & purificación , NAD/metabolismo , NADP/metabolismo , NADP Transhidrogenasas/genética , NADP Transhidrogenasas/aislamiento & purificación , Ácido Oxaloacético/metabolismoRESUMEN
Patient empowerment through self-management education is central to improving the quality of diabetes care and preventing Type 2 Diabetes. Although national programs exist, there is no EU-wide strategy for diabetes self-management education, and patients with limited literacy face barriers to effective self-management. The Diabetes Literacy project, initiated with the support of the European Commission, aims to fill this gap. The project investigates the effectiveness of diabetes self-management education, targeting people with or at risk of Type 2 Diabetes in the 28 EU Member States, as part of a comprehensive EU-wide diabetes strategy. National diabetes strategies in the EU, US, Taiwan, and Israel are compared, and diabetes self-management programs inventorized. The costs of the diabetes care pathway are assessed on a per person basis at national level. A comparison is made of the (cost)-effectiveness of different methods for diabetes self-management support, and the moderating role of health literacy, organization of the health services, and implementation fidelity of education programs are considered. Web-based materials are developed and evaluated by randomized trials to evaluate if interactive internet delivery can enhance self-management support for people with lower levels of health literacy. The 3-year project started in December 2012. Several literature reviews have been produced and protocol development and research design are in the final stages. Primary and secondary data collection and analysis take place in 2014. The results will inform policy decisions on improving the prevention, treatment, and care for persons with diabetes across literacy levels.
Asunto(s)
Diabetes Mellitus Tipo 2/terapia , Alfabetización en Salud , Autocuidado , Costos y Análisis de Costo , Diabetes Mellitus Tipo 2/economía , Alfabetización en Salud/economía , Humanos , Internet , Evaluación de Programas y Proyectos de Salud , Autocuidado/economíaRESUMEN
Mitogen-activated protein kinases are regulators of proliferation and differentiation in many eukaryotes. Studies during the last year have revealed that functionally distinct signal pathways in yeast use related protein kinase cascades for mitogen-activated protein kinase activation. These cascades act as intracellular signaling modules that are likely to be conserved from yeast to mammals.
Asunto(s)
Proteínas Quinasas/metabolismo , Saccharomyces cerevisiae/enzimología , Animales , Proteínas Quinasas Dependientes de Calcio-Calmodulina , Activación Enzimática/efectos de los fármacos , Mitógenos/farmacología , Proteínas Quinasas/genética , Schizosaccharomyces/enzimología , Transducción de SeñalRESUMEN
Mitogen-activated protein kinases function in at least five, physiologically distinct, signaling pathways in yeast. These include pathways that mediate response to mating pheromone, pseudohyphal development and invasive growth, cell integrity, sporulation, and response to high extracellular osmolarity. These kinases and their upstream activating kinases comprise signaling modules that, in at least some cases, exist as multiprotein complexes. Studies during the past year have revealed that the Ste5 protein of the mating pheromone response pathway serves as a scaffold to promote interactions among the protein kinases in this pathway, and to prevent their interaction with kinases of other modules.
Asunto(s)
Proteínas Quinasas/metabolismo , Saccharomyces cerevisiae/enzimología , Transducción de Señal/fisiología , Activación Enzimática , Glicerol/metabolismo , Mitógenos , Concentración Osmolar , Proteína Quinasa C/fisiologíaAsunto(s)
Cardiopatías/diagnóstico , Hemangiosarcoma/diagnóstico , Neoplasias Hepáticas/diagnóstico , Cardiopatías/patología , Hemangiosarcoma/patología , Humanos , Hallazgos Incidentales , Neoplasias Hepáticas/patología , Masculino , Persona de Mediana Edad , Tomografía de Emisión de Positrones/métodos , Tomografía Computarizada por Rayos X/métodosRESUMEN
The current health conditions dictate the need to reduce the time of patient treatment in hospital and require rational use of drugs. Reduction of the duration of intoxication syndrome in severe forms of intestinal infections in children depends on infusion therapy and choice of solutions for intravenous administration. Reamberin is generation IV infusion preparation for intensive care, representing a balanced isotonic detoxicant infusion solution based on succinic acid. Using reamberin ensures a significant decrease in the time of stay in hospital for children with severe forms of intestinal infections, which is achieved by reducing the duration of endogenous intoxication.
Asunto(s)
Enfermedades Transmisibles/tratamiento farmacológico , Cuidados Críticos/métodos , Intestinos/efectos de los fármacos , Infecciones Intraabdominales/tratamiento farmacológico , Meglumina/análogos & derivados , Sustancias Protectoras/uso terapéutico , Succinatos/uso terapéutico , Equilibrio Ácido-Base/efectos de los fármacos , Enfermedad Aguda , Análisis Químico de la Sangre , Estudios de Casos y Controles , Niño , Preescolar , Enfermedades Transmisibles/microbiología , Enfermedades Transmisibles/fisiopatología , Enfermedades Transmisibles/virología , Hemodinámica/efectos de los fármacos , Humanos , Lactante , Inyecciones Intravenosas , Intestinos/microbiología , Intestinos/fisiopatología , Intestinos/virología , Infecciones Intraabdominales/microbiología , Infecciones Intraabdominales/fisiopatología , Infecciones Intraabdominales/virología , Meglumina/administración & dosificación , Meglumina/uso terapéutico , Sustancias Protectoras/administración & dosificación , Federación de Rusia , Succinatos/administración & dosificaciónRESUMEN
The SARS-CoV-2 pandemic has challenged the provision of healthcare in ways that are unprecedented in our lifetime. Planning for the sheer numbers expected during the surge has required public hospitals to de-escalate all non-essential clinical services to focus on COVID-19. Western Cape Province was the initial epicentre of the COVID-19 epidemic in South Africa (SA), and the Cape Town metro was its hardest-hit geographical region. We describe how we constructed our COVID-19 hospital-wide clinical service at Groote Schuur Hospital, the University of Cape Town's tertiary-level teaching hospital. By describing the barriers and enablers, we hope to provide guidance rather than a blueprint for hospitals elsewhere in SA and in low-resource countries that face similar challenges now or during subsequent waves.
Asunto(s)
Infecciones por Coronavirus/diagnóstico , Infecciones por Coronavirus/terapia , Hospitales Universitarios/organización & administración , Neumonía Viral/diagnóstico , Neumonía Viral/terapia , Centros de Atención Terciaria/organización & administración , Betacoronavirus , COVID-19 , Infecciones por Coronavirus/epidemiología , Registros Electrónicos de Salud/organización & administración , Servicio de Urgencia en Hospital/organización & administración , Humanos , Unidades de Cuidados Intensivos/organización & administración , Administración de Materiales de Hospital , Pandemias , Grupo de Atención al Paciente , Neumonía Viral/epidemiología , SARS-CoV-2 , Centros de Atención Secundaria , Sudáfrica/epidemiologíaRESUMEN
The SARS-CoV-2 pandemic has presented clinicians with an enormous challenge in managing a respiratory virus that is not only capable of causing severe pneumonia and acute respiratory distress syndrome, but also multisystem disease. The extraordinary pace of clinical research, and particularly the surge in adaptive trials of new and repurposed treatments, have provided rapid answers to questions of whether such treatments work, and has resulted in corticosteroids taking centre stage in the management of hospitalised patients requiring oxygen support. Some treatment modalities, such as the role of anticoagulation to prevent and treat potential thromboembolic complications, remain controversial, as does the use of high-level oxygen support, outside of an intensive care unit setting. In this paper, we describe the clinical management of COVID-19 patients admitted to Groote Schuur Hospital, a major tertiary level hospital at the epicentre of South Africa's SARS-CoV-2 epidemic during its first 4 months.
Asunto(s)
Infecciones por Coronavirus/terapia , Hospitales Universitarios/organización & administración , Neumonía Viral/terapia , Centros de Atención Terciaria/organización & administración , Corticoesteroides/uso terapéutico , Anticoagulantes/uso terapéutico , Programas de Optimización del Uso de los Antimicrobianos , Betacoronavirus , COVID-19 , Infecciones por Coronavirus/complicaciones , Infecciones por Coronavirus/diagnóstico , Infecciones por Coronavirus/psicología , Cuidados Críticos/organización & administración , Complicaciones de la Diabetes , Humanos , Intubación Intratraqueal , Cuerpo Médico de Hospitales/psicología , Terapia por Inhalación de Oxígeno , Cuidados Paliativos , Pandemias , Grupo de Atención al Paciente , Neumonía Viral/complicaciones , Neumonía Viral/diagnóstico , Neumonía Viral/psicología , Respiración Artificial , Factores de Riesgo , SARS-CoV-2 , Apoyo Social , Sudáfrica/epidemiologíaRESUMEN
The PKC1 gene of Saccharomyces cerevisiae encodes a homologue of the Ca(2+)-dependent isozymes of mammalian protein kinase C (Levin, D.cE., F. O. Fields, R. Kunisawa, J. M. Bishop, and J. Thorner. 1990. Cell. 62:213-224). Cells depleted of the PKC1 gene product display a uniform phenotype, a behavior indicating a defect in the cell division cycle (cdc). These cells arrest division after DNA replication, but before mitosis. Unlike most cdc mutants, which continue to grow in the absence of cell division, PKC1-depleted cells arrest growth with small buds. We created conditional alleles of PKC1 to explore the nature of this unusual cdc defect. In contrast to PKC1-depleted cells, all of the conditional pkc1 mutants isolated were suppressed by the addition of CaCl2 to the medium, suggesting that the mutant enzymes could be activated by Ca2+. Arrest of growth and cell division in the conditional mutants was accompanied by cessation of protein synthesis, rapid loss of viability, and release of cellular material into the medium, suggesting cell lysis. This conclusion was supported by the observation that a pkc1 deletion mutant was capable of proliferation in osmotically stabilized medium, but underwent rapid cell lysis when shifted to hypo-osmotic medium. We have incorporated these observations into a model to explain the cdc-specific arrest of pkc1 mutants.
Asunto(s)
Genes Fúngicos , Fragilidad Osmótica/genética , Proteína Quinasa C/genética , Saccharomyces cerevisiae/genética , Alelos , Secuencia de Aminoácidos , Ciclo Celular/genética , División Celular/genética , Datos de Secuencia Molecular , Mutación , Plásmidos , Alineación de SecuenciaRESUMEN
Saccharomyces cerevisiae has been used as a model for studying the regulation of protein N-myristoylation. MyristoylCoA:protein N-myristoyl-transferase (Nmt1p), is essential for vegetative growth and uses myristoylCoA as its substrate. MyristoylCoA is produced by the fatty acid synthetase (Fas) complex and by cellular acylCoA synthetases. We have recently isolated three unlinked Fatty Acid Activation (FAA) genes encoding long chain acylCoA synthetases and have now recovered a fourth by genetic complementation. When Fas is active and NMT1 cells are grown on media containing a fermentable carbon source, none of the FAA genes is required for vegetative growth. When Fas is inactivated by a specific inhibitor (cerulenin), NMT1 cells are not viable unless the media is supplemented with long chain fatty acids. Supplementation of cellular myristoylCoA pools through activation of imported myristate (C14:0) is predominantly a function of Faa1p, although Faa4p contributes to this process. Cells with nmt181p need larger pools of myristoylCoA because of the mutant enzyme's reduced affinity for this substrate. Faa1p and Faa4p are required for maintaining the viability of nmt1-181 strains even when Fas is active. Overexpression of Faa2p can rescue nmt1-181 cells due to activation of an endogenous pool of C14:0. This pool appears to be derived in part from membrane phospholipids since overexpression of Plb1p, a nonessential lysophospholipase/phospholipase B, suppresses the temperature-sensitive growth arrest and C14:0 auxotrophy produced by nmt1-181. None of the four known FAAs is exclusively responsible for targeting imported fatty acids to peroxisomal beta-oxidation pathways. Introduction of a peroxisomal assembly mutation, pas1 delta, into isogenic NMT1 and nmt1-181 strains with wild type FAA alleles revealed that when Fas is inhibited, peroxisomes contribute to myristoylCoA pools used by Nmt1p. When Fas is active, a fraction of cellular myristoylCoA is targeted to peroxisomes. A NMT1 strain with deletions of all four FAAs is still viable at 30 degrees C on media containing myristate, palmitate, or oleate as the sole carbon source--indicating that S. cerevisiae contains at least one other FAA which directs fatty acids to beta-oxidation pathways.
Asunto(s)
Ácidos Grasos/metabolismo , Proteínas Fúngicas/genética , Genes Fúngicos , Ácidos Mirísticos/metabolismo , Procesamiento Proteico-Postraduccional , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Acilcoenzima A/metabolismo , Secuencia de Aminoácidos , Animales , Bacterias/genética , Secuencia de Bases , Ácido Graso Sintasas/metabolismo , Proteínas Fúngicas/metabolismo , Humanos , Metabolismo de los Lípidos , Mamíferos , Datos de Secuencia Molecular , Ácido Mirístico , Oligodesoxirribonucleótidos , Filogenia , Saccharomyces cerevisiae/crecimiento & desarrollo , Homología de Secuencia de AminoácidoRESUMEN
We hypothesized that some of the heterogeneity of pulmonary blood flow present in the normal human lung in normoxia is due to hypoxic pulmonary vasoconstriction (HPV). If so, mild hyperoxia would decrease the heterogeneity of pulmonary perfusion, whereas it would be increased by mild hypoxia. To test this, six healthy nonsmoking subjects underwent magnetic resonance imaging (MRI) during 20 min of breathing different oxygen concentrations through a face mask [normoxia, inspired O(2) fraction (Fi(O(2))) = 0.21; hypoxia, Fi(O(2)) = 0.125; hyperoxia, Fi(O(2)) = 0.30] in balanced order. Data were acquired on a 1.5-T MRI scanner during a breath hold at functional residual capacity from both coronal and sagittal slices in the right lung. Arterial spin labeling was used to quantify the spatial distribution of pulmonary blood flow in milliliters per minute per cubic centimeter and fast low-angle shot to quantify the regional proton density, allowing perfusion to be expressed as density-normalized perfusion in milliliters per minute per gram. Neither mean proton density [hypoxia, 0.46(0.18) g water/cm(3); normoxia, 0.47(0.18) g water/cm(3); hyperoxia, 0.48(0.17) g water/cm(3); P = 0.28] nor mean density-normalized perfusion [hypoxia, 4.89(2.13) ml x min(-1) x g(-1); normoxia, 4.94(1.88) ml x min(-1) x g(-1); hyperoxia, 5.32(1.83) ml x min(-1) x g(-1); P = 0.72] were significantly different between conditions in either imaging plane. Similarly, perfusion heterogeneity as measured by relative dispersion [hypoxia, 0.74(0.16); normoxia, 0.74(0.10); hyperoxia, 0.76(0.18); P = 0.97], fractal dimension [hypoxia, 1.21(0.04); normoxia, 1.19(0.03); hyperoxia, 1.20(0.04); P = 0.07], log normal shape parameter [hypoxia, 0.62(0.11); normoxia, 0.72(0.11); hyperoxia, 0.70(0.13); P = 0.07], and geometric standard deviation [hypoxia, 1.88(0.20); normoxia, 2.07(0.24); hyperoxia, 2.02(0.28); P = 0.11] was also not different. We conclude that HPV does not affect pulmonary perfusion heterogeneity in normoxia in the normal supine human lung.
Asunto(s)
Hipoxia/fisiopatología , Circulación Pulmonar/fisiología , Posición Supina/fisiología , Vasoconstricción/fisiología , Adulto , Análisis de Varianza , Gasto Cardíaco/fisiología , Femenino , Volumen Espiratorio Forzado/fisiología , Frecuencia Cardíaca/fisiología , Humanos , Pulmón/fisiología , Imagen por Resonancia Magnética , Masculino , Consumo de Oxígeno/fisiología , Perfusión , Pruebas de Función Respiratoria , Resistencia Vascular/fisiologíaRESUMEN
The species concept is a central tenet of biological diversity. Attempts to describe diversity have led to empirical concepts of species based on assumptions found wanting for plants. Plant species lack reality, cohesion, independence, and simple evolutionary or ecological roles. The concept of species for plant taxonomists and evolutionists can only serve as a tool for characterizing diversity in a mentally satisfying way. Diversity is idiosyncratic. ft is impossible to reconcile idiosyncrasy with preconceived ideas of diversity. The search for hidden likenesses is unlikely to yield a unifying species concept. The concept that is most operational and utilitarian for plants is a mental abstraction which orders clusters of diversity in multidimensional character space.
RESUMEN
A plant with four and one with six extra A chromosomes were discovered in a hybrid swarm involving Liatris aspera and Liatris spicata. In each plant, the extra chromosomes formed trivalents with chromosomes of the normal complement. This pairing behavior indicates that of the ten chromosomes in the complement the plants are triplicate for four and six chromosomes, respectively.
Asunto(s)
Aberraciones Cromosómicas , Células Vegetales , Poliploidía , Trisomía , Aneuploidia , Diploidia , Hibridación Genética , MeiosisRESUMEN
1,3-beta-D-glucan synthase [also known as beta(1-->3) glucan synthase] is a multi-enzyme complex that catalyzes the synthesis of 1,3-beta-linked glucan, a major structural component of the yeast cell wall. Temperature-sensitive mutants in the essential Rho-type guanosine triphosphatase (GTPase), Rho1p, displayed thermolabile glucan synthase activity, which was restored by the addition of recombinant Rho1p. Glucan synthase from mutants expressing constitutively active Rho1p did not require exogenous guanosine triphosphate for activity. Rho1p copurified with beta(1-->3)glucan synthase and associated with the Fks1p subunit of this complex in vivo. Both proteins were localized predominantly at sites of cell wall remodeling. Therefore, it appears that Rho1p is a regulatory subunit of beta(1-->3)glucan synthase.
Asunto(s)
GTP Fosfohidrolasas/metabolismo , Proteínas de Unión al GTP/metabolismo , Glucosiltransferasas/metabolismo , Proteínas de la Membrana , Complejos Multienzimáticos/metabolismo , Saccharomyces cerevisiae/enzimología , Proteínas de Schizosaccharomyces pombe , Proteínas de Unión al GTP rho , GTP Fosfohidrolasas/química , GTP Fosfohidrolasas/genética , GTP Fosfohidrolasas/aislamiento & purificación , Proteínas de Unión al GTP/química , Proteínas de Unión al GTP/genética , Proteínas de Unión al GTP/aislamiento & purificación , Glucosiltransferasas/química , Guanosina 5'-O-(3-Tiotrifosfato)/metabolismo , Guanosina 5'-O-(3-Tiotrifosfato)/farmacología , Guanosina Trifosfato/metabolismo , Complejos Multienzimáticos/química , Proteína Quinasa C/metabolismo , Proteínas Recombinantes/metabolismo , Proteínas de Saccharomyces cerevisiae , TemperaturaRESUMEN
OBJECTIVE: To describe a case series of seven women with SLE and other systemic autoimmune rheumatic diseases (SARDs) who required cyclophosphamide therapy and underwent fertility preservation treatments. METHODS: Of the seven patients reported here, five women had SLE with nephritis, the sixth had immune thrombocytopenia purpura (ITP) and the seventh had microscopic polyangiitis (MPA) with renal involvement. All women were nulliparous and younger than 35 yrs. RESULTS: Patients with SLE underwent in vitro maturation (IVM) of immature oocytes aspirated during a natural menstrual cycle followed by vitrification of the matured oocytes if a male partner was not available, or vitrification of embryos if one was available. The patient with ITP and the patient with MPA underwent gonadotropin ovarian stimulation followed by oocyte or embryo vitrification. All women completed fertility preservation treatment successfully and mature oocytes or embryos (36 and 13, respectively) were vitrified. No complications were associated with this treatment and cytotoxic therapy was initiated as scheduled in all cases. CONCLUSIONS: Oocyte or embryo cryopreservation should be considered for fertility preservation in young women with SARDs who face imminent gonadotoxic treatment. In patients, where gonadotropin ovarian stimulation is deemed unsafe, IVM of immature oocytes, aspirated during a natural menstrual cycle, followed by vitrification or fertilization of the mature oocytes, seems to be safe and feasible. For patients in whom hormonal ovarian stimulation is not contraindicated, this method may be considered depending on the urgency to start cytotoxic therapy.
Asunto(s)
Enfermedades Autoinmunes/tratamiento farmacológico , Criopreservación/métodos , Ciclofosfamida/efectos adversos , Inmunosupresores/efectos adversos , Infertilidad Femenina/prevención & control , Adulto , Ciclofosfamida/uso terapéutico , Embrión de Mamíferos , Femenino , Fertilidad , Humanos , Inmunosupresores/uso terapéutico , Infertilidad Femenina/inducido químicamente , Nefritis Lúpica/tratamiento farmacológico , Recuperación del Oocito/métodos , Oocitos , Inducción de la Ovulación/métodosRESUMEN
BACKGROUND: The existence of a Saccharomyces cerevisiae gene encoding a novel isoform of protein kinase C was reported recently in this journal. RESULTS: We demonstrate here that, firstly, the purported PKC2 gene does not reside at the chromosomal location to which it was assigned; secondly, it does not exist as a contiguous sequence in the S. cerevisiae genome; thirdly, some of its reported sequences do exist within other yeast genes; and fourthly, some of its reported sequences, encoding regions of the predicted protein related to protein kinase C, do not exist in any context in the yeast genome. CONCLUSIONS: We conclude from these studies that the PKC2 gene is a composite construction of unrelated yeast and non-yeast sequences.
Asunto(s)
Genes Fúngicos , Proteína Quinasa C/genética , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/enzimología , Saccharomyces cerevisiae/genética , Secuencia de Aminoácidos , Secuencia de Bases , Clonación Molecular , Cartilla de ADN/genética , ADN de Hongos/genética , Proteínas Fúngicas/genética , Genoma Fúngico , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Proteínas de Unión al ARN/genética , Mapeo Restrictivo , Homología de Secuencia de Aminoácido , Homología de Secuencia de Ácido NucleicoRESUMEN
DNA ligase I belongs to a family of proteins that bind to proliferating cell nuclear antigen (PCNA) via a conserved 8-amino-acid motif [1]. Here we examine the biological significance of this interaction. Inactivation of the PCNA-binding site of DNA ligase I had no effect on its catalytic activity or its interaction with DNA polymerase beta. In contrast, the loss of PCNA binding severely compromised the ability of DNA ligase I to join Okazaki fragments. Thus, the interaction between PCNA and DNA ligase I is not only critical for the subnuclear targeting of the ligase, but also for coordination of the molecular transactions that occur during lagging-strand synthesis. A functional PCNA-binding site was also required for the ligase to complement hypersensitivity of the DNA ligase I mutant cell line 46BR.1G1 to monofunctional alkylating agents, indicating that a cytotoxic lesion is repaired by a PCNA-dependent DNA repair pathway. Extracts from 46BR.1G1 cells were defective in long-patch, but not short-patch, base-excision repair (BER). Our results show that the interaction between PCNA and DNA ligase I has a key role in long-patch BER and provide the first evidence for the biological significance of this repair mechanism.
Asunto(s)
ADN Ligasas/metabolismo , Reparación del ADN , ADN/metabolismo , Antígeno Nuclear de Célula en Proliferación/metabolismo , Secuencias de Aminoácidos , Animales , Sitios de Unión , Línea Celular , ADN Ligasa (ATP) , ADN Ligasas/química , ADN Ligasas/genética , Humanos , Mutagénesis Sitio-Dirigida , Antígeno Nuclear de Célula en Proliferación/química , Antígeno Nuclear de Célula en Proliferación/genética , Unión ProteicaRESUMEN
Calcium ion plays a major regulatory role in many hormone-stimulated systems. To determine the site of calcium's action in the toad urinary bladder, we examined the effect of trifluoperazine, a compound that binds specifically to the calcium binding protein, calmodulin, and thereby prevents activation of enzymes by the calcium- calmodulin complex. 10 microM trifluoperazine inhibited vasopressin stimulation of water flow, but did not alter vasopressin's effects on urea permeability or short-circuit current. Trifluoperazine also blocked stimulation of water flow by cyclic AMP and methylisobutylxanthine, implying a "postcyclic AMP" site of action. Consistent with these results, trifluoperazine did not decrease epithelial cyclic AMP content or the cyclic AMP-dependent protein kinase activity ratio. Assay of bladder epithelial supernate demonstrated calmodulin-like activity of 1.5 U/microgram protein. Morphologic studies of vasopressin-treated bladders revealed that trifluoperazine did not alter the volume density of cytoplasmic microtubules or significantly decrease the number of fusions between cytoplasmic, aggregate-containing, elongated vesicles and the luminal membrane. Nonetheless, the frequency of luminal membrane aggregates, structures that correlate well with luminal membrane water permeability, was decreased by greater than 50%. Thus, trifluoperazine appears to inhibit the movement of intramembranous particle aggregates from the fused intracellular membranes to the luminal membrane, perhaps by blocking an effect of calcium on microfilament function.