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Severe congenital Factor XI (FXI) deficiency (<20% normal activity) can be associated with significant bleeding disorders, and there has been great concern for severe bleeding following cardiac surgery requiring cardiopulmonary bypass (CPB) in this patient population. Over the past four decades remarkably different approaches to this problem have been taken, including the administration of blood volumes of fresh frozen plasma, administration of activated recombinant Factor VII, and diminutive administration of heparin. We describe a case wherein the patient was assessed in the perioperative period with a point-of-care, viscoelastic hemostasis device (ROTEM), with changes in the intrinsic/Factor XII-dependent coagulation pathway determined before, during, and after CPB. Fresh frozen plasma was administered in small amounts (5−7.5 mL/kg) just before surgery began and just before cessation of CPB. Administering fresh frozen plasma to the patient to nearly normalize in vitro ROTEM hemostasis values at times when hemostasis was needed resulted in no important bleeding occurring or need of further transfusion of other blood products. In conclusion, by using small amounts of fresh frozen plasma guided by ROTEM, an evidenced-based, precision medicine approach resulted in optimized patient care and outcome.
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BACKGROUND: A transition from a subtyping to a phenotyping approach in rosacea is underway, allowing individual patient management according to presenting features instead of categorization by predefined subtypes. The ROSacea COnsensus (ROSCO) 2017 recommendations further support this transition and align with guidance from other working groups. OBJECTIVES: To update and extend previous global ROSCO recommendations in line with the latest research and continue supporting uptake of the phenotype approach in rosacea through clinical tool development. METHODS: Nineteen dermatologists and two ophthalmologists used a modified Delphi approach to reach consensus on statements pertaining to critical aspects of rosacea diagnosis, classification and management. Voting was electronic and blinded. RESULTS: Delphi statements on which the panel achieved consensus of ≥ 75% voting 'Agree' or 'Strongly agree' are presented. The panel recommends discussing disease burden with patients during consultations, using four questions to assist conversations. The primary treatment objective should be achievement of complete clearance, owing to previously established clinical benefits for patients. Cutaneous and ocular features are defined. Treatments have been reassessed in line with recent evidence and the prior treatment algorithm updated. Combination therapy is recommended to benefit patients with multiple features. Ongoing monitoring and dialogue should take place between physician and patients, covering defined factors to maximize outcomes. A prototype clinical tool (Rosacea Tracker) and patient case studies have been developed from consensus statements. CONCLUSIONS: The current survey updates previous recommendations as a basis for local guideline development and provides clinical tools to facilitate a phenotype approach in practice and improve rosacea patient management. What's already known about this topic? A transition to a phenotype approach in rosacea is underway and is being recommended by multiple working groups. New research has become available since the previous ROSCO consensus, necessitating an update and extension of recommendations. What does this study add? We offer updated global recommendations for clinical practice that account for recent research, to continue supporting the transition to a phenotype approach in rosacea. We present prototype clinical tools to facilitate use of the phenotype approach in practice and improve management of patients with rosacea.
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Oftalmólogos , Rosácea , Terapia Combinada , Consenso , Costo de Enfermedad , Humanos , Rosácea/diagnóstico , Rosácea/terapiaRESUMEN
Fundamentally, material flow stress increases exponentially at deformation rates exceeding, typically, ~103 s-1, resulting in brittle failure. The origin of such behavior derives from the dislocation motion causing non-Arrhenius deformation at higher strain rates due to drag forces from phonon interactions. Here, we discover that this assumption is prevented from manifesting when microstructural length is stabilized at an extremely fine size (nanoscale regime). This divergent strain-rate-insensitive behavior is attributed to a unique microstructure that alters the average dislocation velocity, and distance traveled, preventing/delaying dislocation interaction with phonons until higher strain rates than observed in known systems; thus enabling constant flow-stress response even at extreme conditions. Previously, these extreme loading conditions were unattainable in nanocrystalline materials due to thermal and mechanical instability of their microstructures; thus, these anomalies have never been observed in any other material. Finally, the unique stability leads to high-temperature strength maintained up to 80% of the melting point (~1356 K).
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BACKGROUND: Therapeutic advances have made the achievement of clear/almost clear skin possible for many patients with moderate-to-severe plaque psoriasis. OBJECTIVE: To determine patient perceptions of the impact of psoriasis and of attaining clear/almost clear skin. METHODS: Global survey of patients with moderate-to-severe psoriasis. RESULTS: A total of 8338 patients from 31 countries participated. The majority (57%) had not achieved self-assessed clear/almost clear skin with their current therapy, and 56% of those who had not met this goal believed it would be impossible to do so. Among the patients who had clear/almost clear skin, 73% had not initiated their current treatment until >1 year after psoriasis diagnosis, and 28% had to wait >5 years. Eighty-four percent of all respondents experienced discrimination and/or humiliation due to psoriasis, and many reported negative effects on work, intimate relationships, sleep and mental health. Patients without clear/almost clear skin reported that such achievement would open new possibilities, such as swimming (58%), a wider choice of clothing (40%), and meeting new people (26%). A limitation of this study, as with any survey-based research, is that selection and recall bias may have been present. Additionally, respondent definitions of clear/almost clear skin were subjective and may have varied. CONCLUSION: Despite the importance of clear/almost clear skin to psoriasis patients, most are still not achieving it, and many are unaware it is possible.
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Conocimientos, Actitudes y Práctica en Salud , Percepción , Psoriasis/psicología , Adulto , Femenino , Humanos , Internacionalidad , Masculino , Persona de Mediana Edad , Psoriasis/tratamiento farmacológico , Calidad de Vida , Índice de Severidad de la Enfermedad , Discriminación Social , Encuestas y Cuestionarios , Resultado del TratamientoRESUMEN
The introduction of biological drugs for the treatment of patients with psoriasis has revolutionized treatment paradigms and enabled numerous patients to achieve disease control with an acceptable safety profile. However, the high cost of biologics limits access to these medications for the majority of patients worldwide. In recent years, the introduction of biosimilars for inflammatory diseases has become a fast evolving field. The future use of biosimilars offers the potential for decreased cost and increased access to biologics for patients with psoriasis. For approval of biosimilars, different regulatory agencies use highly variable methods for definition, production, approval, marketing and postmarketing surveillance. Due to potential interchangeability between biologics and biosimilars, traceability and pharmacovigilance are required to collect accurate data about adverse events in patients with psoriasis; spontaneous reporting, registries and use of 'big data' should facilitate this process on a global basis. The current article describes biosimilar regulatory guidelines and examples of biosimilar uptake in clinical practice in several countries around the world. As it is apparent that biological therapy treatment decisions may become more physician independent, the International Psoriasis Council recommends that dermatologists should take an active role in the development of biosimilar prescribing policies with their respective healthcare settings and government agencies.
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Biosimilares Farmacéuticos/uso terapéutico , Fármacos Dermatológicos/uso terapéutico , Psoriasis/tratamiento farmacológico , Biosimilares Farmacéuticos/efectos adversos , Fármacos Dermatológicos/efectos adversos , Dermatólogos/psicología , Aprobación de Drogas , Salud Global , Humanos , Legislación de Medicamentos , Guías de Práctica Clínica como Asunto , Pautas de la Práctica en Medicina , Vigilancia de Productos ComercializadosRESUMEN
AIMS: Stereotactic radiosurgery (SRS) alone or upfront whole brain radiation therapy (WBRT) plus SRS are the most commonly used treatment options for one to three brain oligometastases. The most recent randomised clinical trial result comparing SRS alone with upfront WBRT plus SRS (NCCTG N0574) has favoured SRS alone for neurocognitive function, whereas treatment options remain controversial in terms of cognitive decline and local control. The aim of this study was to conduct a cost-effectiveness analysis of these two competing treatments. MATERIALS AND METHODS: A Markov model was constructed for patients treated with SRS alone or SRS plus upfront WBRT based on largely randomised clinical trials. Costs were based on 2016 Medicare reimbursement. Strategies were compared using the incremental cost-effectiveness ratio (ICER) and effectiveness was measured in quality-adjusted life years (QALYs). One-way and probabilistic sensitivity analyses were carried out. Strategies were evaluated from the healthcare payer's perspective with a willingness-to-pay threshold of $100 000 per QALY gained. RESULTS: In the base case analysis, the median survival was 9 months for both arms. SRS alone resulted in an ICER of $9917 per QALY gained. In one-way sensitivity analyses, results were most sensitive to variation in cognitive decline rates for both groups and median survival rates, but the SRS alone remained cost-effective for most parameter ranges. CONCLUSIONS: Based on the current available evidence, SRS alone was found to be cost-effective for patients with one to three brain metastases compared with upfront WBRT plus SRS.
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Neoplasias Encefálicas/secundario , Análisis Costo-Beneficio/economía , Irradiación Craneana/economía , Radiocirugia/economía , Análisis Costo-Beneficio/métodos , Irradiación Craneana/métodos , Femenino , Humanos , Masculino , Radiocirugia/métodosRESUMEN
BACKGROUND: Rosacea is currently diagnosed by consensus-defined primary and secondary features and managed by subtype. However, individual features (phenotypes) can span multiple subtypes, which has implications for clinical practice and research. Adopting a phenotype-led approach may facilitate patient-centred management. OBJECTIVES: To advance clinical practice by obtaining international consensus to establish a phenotype-led rosacea diagnosis and classification scheme with global representation. METHODS: Seventeen dermatologists and three ophthalmologists used a modified Delphi approach to reach consensus on statements pertaining to critical aspects of rosacea diagnosis, classification and severity evaluation. All voting was electronic and blinded. RESULTS: Consensus was achieved for transitioning to a phenotype-based approach to rosacea diagnosis and classification. The following two features were independently considered diagnostic for rosacea: (i) persistent, centrofacial erythema associated with periodic intensification; and (ii) phymatous changes. Flushing, telangiectasia, inflammatory lesions and ocular manifestations were not considered to be individually diagnostic. The panel reached agreement on dimensions for phenotype severity measures and established the importance of assessing the patient burden of rosacea. CONCLUSIONS: The panel recommended an approach for diagnosis and classification of rosacea based on disease phenotype.
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Oftalmopatías/diagnóstico , Rosácea/diagnóstico , Índice de Severidad de la Enfermedad , Edad de Inicio , Consenso , Costo de Enfermedad , Dermatitis/etiología , Dermatólogos , Oftalmopatías/clasificación , Humanos , Cooperación Internacional , Estilo de Vida , Oftalmólogos , Planificación de Atención al Paciente , Rosácea/clasificación , Pigmentación de la Piel/fisiología , Telangiectasia/etiologíaRESUMEN
BACKGROUND: Rosacea is currently treated according to subtypes. As this does not adequately address the spectrum of clinical presentation (phenotypes), it has implications for patient management. The ROSacea COnsensus panel was established to address this issue. OBJECTIVES: To incorporate current best treatment evidence with clinical experience from an international expert panel and establish consensus to improve outcomes for patients with rosacea. METHODS: Seventeen dermatologists and three ophthalmologists reached consensus on critical aspects of rosacea treatment and management using a modified Delphi approach. The panel voted on statements using the responses 'strongly disagree', 'disagree', 'agree' or 'strongly agree'. Consensus was defined as ≥ 75% 'agree' or 'strongly agree'. All voting was electronic and blinded. RESULTS: The panel agreed on phenotype-based treatments for signs and symptoms presenting in individuals with rosacea. First-line treatments were identified for individual major features of transient and persistent erythema, inflammatory papules/pustules, telangiectasia and phyma, underpinned by general skincare measures. Multiple features in an individual patient can be simultaneously treated with multiple agents. If treatment is inadequate given appropriate duration, another first-line option or the addition of another first-line agent should be considered. Maintenance treatment depends on treatment modality and patient preferences. Ophthalmological referral for all but the mildest ocular features should be considered. Lid hygiene and artificial tears in addition to medications are used to treat ocular rosacea. CONCLUSIONS: Rosacea diagnosis and treatment should be based on clinical presentation. Consensus was achieved to support this approach for rosacea treatment strategies.
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Fármacos Dermatológicos/uso terapéutico , Rosácea/tratamiento farmacológico , Algoritmos , Consenso , Cosmecéuticos/uso terapéutico , Quimioterapia Combinada , Oftalmopatías/tratamiento farmacológico , Humanos , Cuidados de la Piel/métodos , Protectores Solares/uso terapéutico , Resultado del TratamientoRESUMEN
Biosimilars are drugs that are similar, but not identical, to originator biologics. Preclinical analytical studies are required to show similarity on a molecular and structural level, but efficacy and safety studies in humans are essential to determining biosimilarity. In this review, written by members of the International Psoriasis Council, we discuss how biosimilars are evaluated in a clinical setting, with emphasis on extrapolation of indication, interchangeability and optimal clinical trial design.
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Biosimilares Farmacéuticos/uso terapéutico , Psoriasis/tratamiento farmacológico , Anticuerpos Monoclonales Humanizados/uso terapéutico , Ensayos Clínicos como Asunto , Aprobación de Drogas , Humanos , Guías de Práctica Clínica como AsuntoRESUMEN
Nanocrystalline metals, with a mean grain size of less than 100 nanometres, have greater room-temperature strength than their coarse-grained equivalents, in part owing to a large reduction in grain size. However, this high strength generally comes with substantial losses in other mechanical properties, such as creep resistance, which limits their practical utility; for example, creep rates in nanocrystalline copper are about four orders of magnitude higher than those in typical coarse-grained copper. The degradation of creep resistance in nanocrystalline materials is in part due to an increase in the volume fraction of grain boundaries, which lack long-range crystalline order and lead to processes such as diffusional creep, sliding and rotation. Here we show that nanocrystalline copper-tantalum alloys possess an unprecedented combination of properties: high strength combined with extremely high-temperature creep resistance, while maintaining mechanical and thermal stability. Precursory work on this family of immiscible alloys has previously highlighted their thermo-mechanical stability and strength, which has motivated their study under more extreme conditions, such as creep. We find a steady-state creep rate of less than 10(-6) per second-six to eight orders of magnitude lower than most nanocrystalline metals-at various temperatures between 0.5 and 0.64 times the melting temperature of the matrix (1,356 kelvin) under an applied stress ranging from 0.85 per cent to 1.2 per cent of the shear modulus. The unusual combination of properties in our nanocrystalline alloy is achieved via a processing route that creates distinct nanoclusters of atoms that pin grain boundaries within the alloy. This pinning improves the kinetic stability of the grains by increasing the energy barrier for grain-boundary sliding and rotation and by inhibiting grain coarsening, under extremely long-term creep conditions. Our processing approach should enable the development of microstructurally stable structural alloys with high strength and creep resistance for various high-temperature applications, including in the aerospace, naval, civilian infrastructure and energy sectors.
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We present a case of young male with end-stage renal disease due to type III membranoproliferative glomerulonephritis (GN) and clinical features consistent with Behcet's disease (BD). He developed flare of BD 3 months after deceased donor renal transplantation following cytomegalovirus infection, in the form of oral and genital ulcers. He also had GN characterized by mild mesangial proliferation, neutrophilic infiltration and subepithelial, mesangial and intramembranous electron dense deposits, which could possibly be attributed to recurrence of renal disease due to BD. The clinical flare of BD was treated with colchicine with good response.
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We recently showed that two small membrane proteins of Mycobacterium tuberculosis, CwsA and CrgA, interact with each other, and that loss of CwsA in M. smegmatis is associated with defects in the cell division and cell wall synthesis processes. Here we show that CwsA overproduction also affected growth, cell division and cell shape of M. smegmatis and M. tuberculosis. CwsA overproduction in M. tuberculosis led to increased sensitivity to cefsulodin, a penicillin-binding protein (PBP) 1A/1B targeting beta (ß) -lactam, but was unaffected by other ß-lactams and vancomycin. A M. smegmatis cwsA overexpressing strain showed bulgy cells, increased fluorescent vancomycin staining and altered localization of Wag31-mCherry fusion protein. However, the levels of phosphorylated Wag31, important for optimal peptidoglycan synthesis and growth in mycobacteria, were not affected. Interestingly, CwsA overproduction in E. coli led to the formation of large rounded cells that eventually lysed whereas the overproduction of FtsZ along with CwsA reversed this phenotype. Together, our results emphasize that optimal levels of CwsA are required for regulated cell wall synthesis, hence maintenance of cell shape, and that CwsA likely interacts with and modulates the activities of other cell wall synthetic components including PBPs.
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Proteínas Bacterianas/metabolismo , Pared Celular/metabolismo , Escherichia coli/crecimiento & desarrollo , Proteínas de la Membrana/metabolismo , Mycobacterium smegmatis/metabolismo , Mycobacterium tuberculosis/metabolismo , Antibacterianos/farmacología , División Celular , Células Cultivadas , Escherichia coli/efectos de los fármacos , Regulación Bacteriana de la Expresión Génica , Humanos , Immunoblotting , Marcaje Isotópico , Unión Proteica , Mapeo de Interacción de Proteínas , Regulación hacia ArribaRESUMEN
Bacterial cell division and cell wall synthesis are highly coordinated processes involving multiple proteins. Here, we show that Rv0008c, a novel small membrane protein from Mycobacterium tuberculosis, localizes to the poles and on membranes and shows an overall punctate localization throughout the cell. Furthermore, Rv0008c interacts with two proteins, CrgA and Wag31, implicated in peptidoglycan (PG) synthesis in mycobacteria. Deletion of the Rv0008c homolog in M. smegmatis, MSMEG_0023, caused bulged cell poles, formation of rounded cells, and defects in polar localization of Wag31 and cell wall synthesis, with cell wall synthesis measured by the incorporation of the [(14)C]N-acetylglucosamine cell wall precursor. The M. smegmatis MSMEG_0023 crgA double mutant strain showed severe defects in growth, viability, cell wall synthesis, cell shape, and the localization of the FtsZ, FtsI, and Wag31 proteins. The double mutant strain also exhibited increased autolytic activity in the presence of detergents. Because CrgA and Wag31 proteins interact with FtsI individually, we believe that regulated cell wall synthesis and cell shape maintenance require the concerted actions of the CrgA, Rv0008c, FtsI, and Wag31 proteins. We propose that, together, CrgA and Rv0008c, renamed CwsA for cell wall synthesis and cell shape protein A, play crucial roles in septal and polar PG synthesis and help coordinate these processes with the FtsZ-ring assembly in mycobacteria.
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Proteínas Bacterianas/metabolismo , Pared Celular/metabolismo , Mycobacterium tuberculosis/citología , Mycobacterium tuberculosis/fisiología , Peptidoglicano/biosíntesis , Mapeo de Interacción de Proteínas , Acetilglucosamina/metabolismo , Radioisótopos de Carbono/metabolismo , Eliminación de Gen , Marcaje Isotópico , Mycobacterium smegmatis/citología , Mycobacterium smegmatis/genética , Mycobacterium tuberculosis/metabolismo , Unión Proteica , Factores de Transcripción/metabolismoRESUMEN
Contribution of terrestrial radiation due to the presence of naturally occurring radionuclides in soil and air constitutes a significant component of the background radiation exposure to the population. The concentrations of natural radionuclides in the soil and indoor air of Chellanam were investigated with an aim of evaluating the environmental radioactivity level and radiation hazard to the population. Chellanam is in the suburbs of Cochin, with the Arabian Sea in the west and the Cochin backwaters in the east. Chellanam is situated at â¼25 km from the sites of these factories. The data obtained serve as a reference in documenting changes to the environmental radioactivity due to technical activities. Soil samples were collected from 30 locations of the study area. The activity concentrations of (232)Th, (238)U and (40)K in the samples were analysed using gamma spectrometry. The gamma dose rates were calculated using conversion factors recommended by UNSCEAR [United Nations Scientific Committee on the Effects of Atomic Radiation. Sources and effects of ionizing radiation. UNSCEAR (2000)]. The ambient radiation exposure rates measured in the area ranged from 74 to 195 nGy h(-1) with a mean value of 131 nGy h(-1). The significant radionuclides being (232)Th, (238)U and (40)K, their activities were used to arrive at the absorbed gamma dose rate with a mean value of 131 nGy h(-1) and the radium equivalent activity with a mean value of 162 Bq kg(-1). The radon progeny levels varied from 0.21 to 1.4 mWL with a mean value of 0.6 mWL. The thoron progeny varied from 0.34 to 2.9 mWL with a mean value of 0.85 mWL. The ratio between thoron and radon progenies varied from 1.4 to 2.3 with a mean of 1.6. The details of the study, analysis and results are discussed.
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Contaminantes Radiactivos del Aire/análisis , Contaminación del Aire Interior/análisis , Radiación de Fondo , Monitoreo de Radiación/métodos , Radiactividad , Radiometría/métodos , Calibración , India , Radioisótopos de Potasio/análisis , Radioisótopos/análisis , Radio (Elemento)/análisis , Radón/análisis , Dióxido de Silicio , Suelo , Contaminantes Radiactivos del Suelo/análisis , Espectrometría gamma/métodos , Torio/análisis , Uranio/análisisRESUMEN
The role(s) in cell division of the Mycobacterium tuberculosis Rv0011c gene product, a homolog of the Streptomyces CrgA protein that is responsible for coordinating growth and cytokinesis in sporogenic aerial hyphae, is largely unknown. We show that an enhanced cyan fluorescent protein-M. tuberculosis CrgA (ECFP-CrgA(MT)) fusion protein is localized to the cell membrane, midcell, and cell pole regions in Mycobacterium smegmatis. Furthermore, the ECFP-CrgA(MT) fusion protein colocalized with FtsZ-enhanced yellow fluorescent protein (EYFP) in M. smegmatis. Bacterial two-hybrid assays indicated strong interactions of M. tuberculosis CrgA with FtsZ, FtsQ, and the class B penicillin-binding proteins, FtsI (PBPB) and PBPA. The midcell localization of CrgA(MT) was severely compromised under conditions of FtsZ depletion, which indicated that CrgA localizes to the midcell region after assembly of the FtsZ ring. M. tuberculosis cells with reduced CrgA levels were elongated and grew more slowly than wild-type cells, which indicated defects in cell division, whereas CrgA overproduction did not show growth defects. A M. smegmatis ΔcrgA strain exhibited a bulged cell morphology, elongated cells with a chain-like phenotype, cells with polar bulbous structures, and a modest growth defect. FtsZ and FtsI levels were not affected in cells producing altered levels of CrgA. Septal and membrane localization of GFP-FtsI was enhanced by CrgA overproduction and was diminished in a ΔcrgA strain, which indicates that one role of CrgA is to promote and/or stabilize FtsI localization. Overall, these data indicate that CrgA is a novel member of the cell division complex in mycobacteria and possibly facilitates septum formation.
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Proteínas Bacterianas/metabolismo , Mycobacterium tuberculosis/metabolismo , Peptidoglicano/biosíntesis , Factores de Transcripción/metabolismo , Proteínas Bacterianas/análisis , Membrana Celular/química , Proteínas del Citoesqueleto/análisis , Genes Reporteros , Proteínas Fluorescentes Verdes/análisis , Proteínas Fluorescentes Verdes/genética , Microscopía Confocal , Mycobacterium tuberculosis/química , Mycobacterium tuberculosis/citología , Mycobacterium tuberculosis/genética , Proteínas de Unión a las Penicilinas/metabolismo , Unión Proteica , Mapeo de Interacción de Proteínas , Proteínas Recombinantes de Fusión/análisis , Proteínas Recombinantes de Fusión/genética , Técnicas del Sistema de Dos HíbridosRESUMEN
Intein is a protein sequence mebedded in-frame within a precursor protein and is posttranslationally excised by a self-catalytic protein splicing process. Protein splicing is believed to follow a pathway requiring Cys, Ser, or Thr residues at the intein N-terminus and substitutions other than Cys, Ser, or Thr residues prevent splicing. We show that the dnaB locus in some strains of M. avium-intracellulare complex (MAC) contains intein and that the intein N-terminal amino acid is Ala [Ala-type]. We demonstrate that the M. avium DnaB precursor protein undergoes posttranslational proteolytic processing producing proteins corresponding to the sizes of the DnaB and intein. Further, by Western analysis we detect a protein corresponding to the size of the spliced DnaB protein in MAC cell extracts. Together, these results indicate that the Ala-type MAC DnaB inteins can splice and provide another example that points to an interesting alternative splicing mechanism (Southworth, M. W., Benner, J., and Perler, F. B., EMBO J. 19, 5019-5026, 2000).
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Proteínas Bacterianas , ADN Helicasas/genética , ADN Helicasas/metabolismo , Complejo Mycobacterium avium/genética , Complejo Mycobacterium avium/metabolismo , Secuencia de Bases , ADN Helicasas/química , Cartilla de ADN/genética , AdnB Helicasas , Genes Bacterianos , Precursores de Proteínas/química , Precursores de Proteínas/genética , Precursores de Proteínas/metabolismo , Empalme de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismoRESUMEN
A two-step protocol has been developed for isolation of plasmids from recombinant mycobacteria via Escherichia coli. First either mycobacterial primary transformants or propagated cultures were lysed in a mini-bead beater using zirconia beads and the lysate thus obtained was used to transform E. coli recA mutant cells. Secondly, plasmid DNA was isolated from recombinant E. coli cells and analysed. Bead beating times of 2 min for Mycobacterium smegmatis, a rapid grower, and 4 min for M. bovis BCG, a slow grower, were found to be optimal for recovery of plasmid DNA. This protocol was also amenable to other mycobacterial species such as M. avium, M. fortuitum and M. tuberculosis H37Ra. Plasmid recovery from the recombinant M. bovis BCG using this protocol is approximately 300-fold higher than that reported for the electroduction method.
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Mycobacterium/genética , Micobacterias no Tuberculosas/genética , Plásmidos/aislamiento & purificación , Southern Blotting , Escherichia coli/genética , Microesferas , Factores de Tiempo , Transformación Bacteriana , CirconioRESUMEN
A 3.9 kb DNA fragment containing the dnaA gene region of Mycobacterium avium was cloned and its nucleotide sequence was determined. Nucleotide sequence analyses indicated that this region encodes three genes in the order rpmH (ribosomal protein L34), dnaA (the putative initiator protein) and dnaN (the beta subunit of DNA polymerase III). The intergenic regions between the rpmH-dnaA and dnaA-dnaN genes were found to contain several putative DnaA boxes, 9 nt long DnaA protein recognition sequences. A DNA fragment containing the 3' but not the 5' flanking region of the M. avium dnaA gene when cloned in Escherichia coli plasmids, which are otherwise non-replicative in mycobacteria, exhibited autonomous replication activity in M. avium but not in Mycobacterium bovis BCG and Mycobacterium smegmatis. The 5' flanking region of dnaA, on the other hand, exhibited autonomous replication activity in M. bovis BCG but not in M. avium and M. smegmatis. The implications of these results for the understanding of the M. avium oriC replication initiation process are discussed.
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Regiones no Traducidas 3'/metabolismo , Regiones no Traducidas 5'/metabolismo , Proteínas Bacterianas/genética , Proteínas de Unión al ADN/genética , ADN Polimerasa Dirigida por ADN , Complejo Mycobacterium avium/genética , Regiones no Traducidas 3'/genética , Regiones no Traducidas 5'/genética , Proteínas Bacterianas/biosíntesis , Secuencia de Bases , Mapeo Cromosómico , Cromosomas Bacterianos/genética , Replicación del ADN/genética , Replicación del ADN/fisiología , ADN Bacteriano/metabolismo , Datos de Secuencia Molecular , Mycobacterium bovis/genética , Mycobacterium smegmatis/genética , Mycobacterium tuberculosis/genética , Proteínas Recombinantes/biosíntesis , Origen de Réplica/genética , Origen de Réplica/fisiología , Proteínas Ribosómicas/genética , Alineación de Secuencia , Análisis de Secuencia de ADNRESUMEN
OBJECTIVE: We report a patient who developed discontinuation symptoms following nefazodone cessation. CLINICAL PICTURE: The patient experienced nausea, vomiting, diarrhoea, ataxia, insomnia, marked agitation, headache and flu-like symptoms. TREATMENT: She was reluctant to recommence nefazodone and was symptomatically treated with oxazepam. OUTCOME: The patient recovered completely in 10 days. CONCLUSIONS: Nefazodone discontinuation can result in withdrawal symptoms and therefore needs to be tapered gradually. Those who have experienced discontinuation symptoms with other antidepressants in the past may be at increased risk.