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OBJECTIVE: To explore the attitudes and beliefs of cardiac rehabilitation and stroke teams towards adapted cardiac rehabilitation, and the broader topics of exercise, healthy lifestyles and health behaviour change, for people with mild-to-moderate severity stroke in the sub-acute phase of recovery. DESIGN: Qualitative focus group-based study. SETTING: Acute and community national health service trusts. PARTICIPANTS: Stroke and cardiac rehabilitation team members. INTERVENTION: Adapted cardiac rehabilitation. MAIN MEASURES: Focus groups. Thematic analysis was applied to the transcribed data. RESULTS: Overall, 57 health professionals participated in 12 focus groups. Positive impacts for teams and stroke survivors were identified particularly confidence. However, there were negatives, barriers and adaptations identified. In addition, there was a lack of knowledge for cardiac rehabilitation teams in relation to stroke survivors and stroke teams in relation to cardiac rehabilitation, exercise and healthy lifestyles. CONCLUSIONS: Cardiac rehabilitation and stroke staff attitudes to cardiac rehabilitation for stroke survivors showed a range of benefits, negatives, barriers and adaptations needed. Confidence and knowledge of the cardiac rehabilitation and stroke teams needs to be addressed. REGISTRATION: ISRCTN65957980.
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The arsenal of drugs used to treat leishmaniasis, caused by Leishmania spp., is limited and beset by toxicity and emergent resistance. Furthermore, our understanding of drug mode of action and potential routes to resistance is limited. Forward genetic approaches have revolutionized our understanding of drug mode of action in the related kinetoplastid parasite Trypanosoma brucei Therefore, we screened our genome-scale T. brucei RNA interference (RNAi) library against the current antileishmanial drugs sodium stibogluconate (antimonial), paromomycin, miltefosine, and amphotericin B. Identification of T. brucei orthologues of the known Leishmania antimonial and miltefosine plasma membrane transporters effectively validated our approach, while a cohort of 42 novel drug efficacy determinants provides new insights and serves as a resource. Follow-up analyses revealed the antimonial selectivity of the aquaglyceroporin TbAQP3. A lysosomal major facilitator superfamily transporter contributes to paromomycin-aminoglycoside efficacy. The vesicle-associated membrane protein TbVAMP7B and a flippase contribute to amphotericin B and miltefosine action and are potential cross-resistance determinants. Finally, multiple phospholipid-transporting flippases, including the T. brucei orthologue of the Leishmania miltefosine transporter, a putative ß-subunit/CDC50 cofactor, and additional membrane-associated hits, affect amphotericin B efficacy, providing new insights into mechanisms of drug uptake and action. The findings from this orthology-based chemogenomic profiling approach substantially advance our understanding of antileishmanial drug action and potential resistance mechanisms and should facilitate the development of improved therapies as well as surveillance for drug-resistant parasites.
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Antiprotozoarios/farmacología , Trypanosoma brucei brucei/metabolismo , Adenosina Trifosfatasas/metabolismo , Anfotericina B/farmacología , Gluconato de Sodio Antimonio/farmacología , Leishmania/parasitología , Paromomicina/farmacología , Fosforilcolina/análogos & derivados , Fosforilcolina/farmacología , Proteínas R-SNARE/metabolismo , Trypanosoma brucei brucei/efectos de los fármacos , Trypanosoma brucei brucei/genéticaRESUMEN
Aquaglyceroporins (AQPs) transport water and glycerol and play important roles in drug-uptake in pathogenic trypanosomatids. For example, AQP2 in the human-infectious African trypanosome, Trypanosoma brucei gambiense, is responsible for melarsoprol and pentamidine-uptake, and melarsoprol treatment-failure has been found to be due to AQP2-defects in these parasites. To further probe the roles of these transporters, we assembled a T. b. brucei strain lacking all three AQP-genes. Triple-null aqp1-2-3 T. b. brucei displayed only a very moderate growth defect in vitro, established infections in mice and recovered effectively from hypotonic-shock. The aqp1-2-3 trypanosomes did, however, display glycerol uptake and efflux defects. They failed to accumulate glycerol or to utilise glycerol as a carbon-source and displayed increased sensitivity to salicylhydroxamic acid (SHAM), octyl gallate or propyl gallate; these inhibitors of trypanosome alternative oxidase (TAO) can increase intracellular glycerol to toxic levels. Notably, disruption of AQP2 alone generated cells with glycerol transport defects. Consistent with these findings, AQP2-defective, melarsoprol-resistant clinical isolates were sensitive to the TAO inhibitors, SHAM, propyl gallate and ascofuranone, relative to melarsoprol-sensitive reference strains. We conclude that African trypanosome AQPs are dispensable for viability and osmoregulation but they make important contributions to drug-uptake, glycerol-transport and respiratory-inhibitor sensitivity. We also discuss how the AQP-dependent inverse sensitivity to melarsoprol and respiratory inhibitors described here might be exploited.
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Acuagliceroporinas/metabolismo , Resistencia a Medicamentos/fisiología , Tripanosomiasis Africana/metabolismo , Animales , Transporte Biológico/efectos de los fármacos , Modelos Animales de Enfermedad , Resistencia a Medicamentos/efectos de los fármacos , Técnicas de Inactivación de Genes , Glicerol/metabolismo , Melarsoprol/farmacología , Ratones , Ratones Endogámicos BALB C , Tripanocidas/farmacología , Trypanosoma brucei gambiense/metabolismoRESUMEN
The chemotherapeutic arsenal against human African trypanosomiasis, sleeping sickness, is limited and can cause severe, often fatal, side effects. One of the classic and most widely used drugs is pentamidine, an aromatic diamidine compound introduced in the 1940s. Recently, a genome-wide loss-of-function screen and a subsequently generated trypanosome knockout strain revealed a specific aquaglyceroporin, TbAQP2, to be required for high-affinity uptake of pentamidine. Yet, the underlying mechanism remained unclear. Here, we show that TbAQP2 is not a direct transporter for the di-basic, positively charged pentamidine. Even though one of the two common cation filters of aquaglyceroporins, i.e. the aromatic/arginine selectivity filter, is unconventional in TbAQP2, positively charged compounds are still excluded from passing the channel. We found, instead, that the unique selectivity filter layout renders pentamidine a nanomolar inhibitor of TbAQP2 glycerol permeability. Full, non-covalent inhibition of an aqua(glycero)porin in the nanomolar range has not been achieved before. The remarkable affinity derives from an electrostatic interaction with Asp265 and shielding from water as shown by structure-function evaluation and point mutation of Asp265. Exchange of the preceding Leu264 to arginine abolished pentamidine-binding and parasites expressing this mutant were pentamidine-resistant. Our results indicate that TbAQP2 is a high-affinity receptor for pentamidine. Taken together with localization of TbAQP2 in the flagellar pocket of bloodstream trypanosomes, we propose that pentamidine uptake is by endocytosis.
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Acuagliceroporinas/metabolismo , Pentamidina/farmacología , Tripanocidas/farmacología , Trypanosoma brucei brucei/efectos de los fármacos , Animales , Resistencia a Medicamentos/genética , Humanos , Tripanosomiasis Africana/tratamiento farmacológicoRESUMEN
The concept of disease-specific chemotherapy was developed a century ago. Dyes and arsenical compounds that displayed selectivity against trypanosomes were central to this work, and the drugs that emerged remain in use for treating human African trypanosomiasis (HAT). The importance of understanding the mechanisms underlying selective drug action and resistance for the development of improved HAT therapies has been recognized, but these mechanisms have remained largely unknown. Here we use all five current HAT drugs for genome-scale RNA interference target sequencing (RIT-seq) screens in Trypanosoma brucei, revealing the transporters, organelles, enzymes and metabolic pathways that function to facilitate antitrypanosomal drug action. RIT-seq profiling identifies both known drug importers and the only known pro-drug activator, and links more than fifty additional genes to drug action. A bloodstream stage-specific invariant surface glycoprotein (ISG75) family mediates suramin uptake, and the AP1 adaptin complex, lysosomal proteases and major lysosomal transmembrane protein, as well as spermidine and N-acetylglucosamine biosynthesis, all contribute to suramin action. Further screens link ubiquinone availability to nitro-drug action, plasma membrane P-type H(+)-ATPases to pentamidine action, and trypanothione and several putative kinases to melarsoprol action. We also demonstrate a major role for aquaglyceroporins in pentamidine and melarsoprol cross-resistance. These advances in our understanding of mechanisms of antitrypanosomal drug efficacy and resistance will aid the rational design of new therapies and help to combat drug resistance, and provide unprecedented molecular insight into the mode of action of antitrypanosomal drugs.
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Resistencia a Medicamentos/genética , Tripanocidas/farmacología , Trypanosoma brucei brucei/efectos de los fármacos , Tripanosomiasis Africana/tratamiento farmacológico , Acuagliceroporinas/deficiencia , Acuagliceroporinas/metabolismo , Eflornitina/farmacología , Endocitosis/efectos de los fármacos , Glicosilación/efectos de los fármacos , Ensayos Analíticos de Alto Rendimiento , Humanos , Lisosomas/efectos de los fármacos , Lisosomas/metabolismo , Melarsoprol/farmacología , Nifurtimox/farmacología , Pentamidina/farmacología , Interferencia de ARN , Suramina/farmacología , Tripanocidas/uso terapéutico , Trypanosoma brucei brucei/citología , Trypanosoma brucei brucei/enzimología , Trypanosoma brucei brucei/metabolismo , Tripanosomiasis Africana/genéticaRESUMEN
STUDY OBJECTIVE: There is significant overlap between the symptoms of patients presenting with retinal detachment (RD) and posterior vitreous detachment (PVD). Urgency to obtain consultation and treatment are dependent on the ability to accurately distinguish these two conditions. The objective of this study was to determine the ability of emergency physicians to differentiate RDs from PVDs using point-of-care (POC) ocular ultrasound. METHODS: Single blinded cross-sectional study at an academic medical center. Emergency physicians with varying ultrasound experience completed a brief tutorial on the sonographic findings of RD and PVD. Thirty POC ocular ultrasound clips obtained from ED patients with ocular symptoms were presented to emergency physicians. The sonographic findings in these clips were in agreement with the final diagnosis made by consultant ophthalmologists. There were 14 ultrasound videos showing PVD, 13 videos showing RD, and 3 normal ocular ultrasound videos. The subjects independently reviewed POC ocular ultrasound video clips and submitted their final interpretations. RESULTS: A total of 390 ocular video clips were reviewed by 13 emergency physicians. Overall, physicians were able to accurately diagnose the presence of a RD 74.6% (95%CI, 69.8-79.4) of the time, PVD 85.7% (95%CI, 77.6-93.8) of the time, and normal ultrasounds 94.9% (95%CI 87.3-100.0) of the time. There was no statistically significant relationship between correct diagnoses for ocular abnormalities or normal ultrasound images and number of previous ocular ultrasounds performed by emergency physicians. CONCLUSION: Emergency physicians were modestly accurate in distinguishing RD from PVD on POC ultrasound.
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Competencia Clínica/estadística & datos numéricos , Servicio de Urgencia en Hospital , Médicos , Sistemas de Atención de Punto , Desprendimiento de Retina/diagnóstico por imagen , Ultrasonografía , Desprendimiento del Vítreo/diagnóstico por imagen , Estudios Transversales , Diagnóstico Diferencial , Humanos , Médicos/normas , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Método Simple Ciego , Ultrasonido/educación , Grabación en VideoRESUMEN
Kinetoplastid parasites cause lethal diseases in humans and animals. The kinetoplast itself contains the mitochondrial genome, comprising a huge, complex DNA network that is also an important drug target. Isometamidium, for example, is a key veterinary drug that accumulates in the kinetoplast in African trypanosomes. Kinetoplast independence and isometamidium resistance are observed where certain mutations in the F1-γ-subunit of the two-sector F1Fo-ATP synthase allow for Fo-independent generation of a mitochondrial membrane potential. To further explore kinetoplast biology and drug resistance, we screened a genome-scale RNA interference library in African trypanosomes for isometamidium resistance mechanisms. Our screen identified 14 V-ATPase subunits and all 4 adaptin-3 subunits, implicating acidic compartment defects in resistance; V-ATPase acidifies lysosomes and related organelles, whereas adaptin-3 is responsible for trafficking among these organelles. Independent strains with depleted V-ATPase or adaptin-3 subunits were isometamidium resistant, and chemical inhibition of the V-ATPase phenocopied this effect. While drug accumulation in the kinetoplast continued after V-ATPase subunit depletion, acriflavine-induced kinetoplast loss was specifically tolerated in these cells and in cells depleted for adaptin-3 or endoplasmic reticulum membrane complex subunits, also identified in our screen. Consistent with kinetoplast dispensability, V-ATPase defective cells were oligomycin resistant, suggesting ATP synthase uncoupling and bypass of the normal Fo-A6-subunit requirement; this subunit is the only kinetoplast-encoded product ultimately required for viability in bloodstream-form trypanosomes. Thus, we describe 30 genes and 3 protein complexes associated with kinetoplast-dependent growth. Mutations affecting these genes could explain natural cases of dyskinetoplasty and multidrug resistance. Our results also reveal potentially conserved communication between the compartmentalized two-sector rotary ATPases.
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ADN de Cinetoplasto/metabolismo , Resistencia a Medicamentos , Mitocondrias/enzimología , ATPasas de Translocación de Protón/metabolismo , Trypanosoma brucei brucei/enzimología , ATPasas de Translocación de Protón Vacuolares/metabolismo , Ácidos/metabolismo , Animales , Compartimento Celular/efectos de los fármacos , Resistencia a Medicamentos/efectos de los fármacos , Retículo Endoplásmico/efectos de los fármacos , Retículo Endoplásmico/metabolismo , Membranas Intracelulares/efectos de los fármacos , Membranas Intracelulares/metabolismo , Mitocondrias/efectos de los fármacos , Fenantridinas/química , Fenantridinas/farmacología , Reacción en Cadena de la Polimerasa , Subunidades de Proteína/metabolismo , Interferencia de ARN/efectos de los fármacos , Reproducibilidad de los Resultados , Trypanosoma brucei brucei/efectos de los fármacos , Trypanosoma brucei brucei/genéticaRESUMEN
Trypanosoma brucei rhodesiense is one of the causative agents of human sleeping sickness, a fatal disease that is transmitted by tsetse flies and restricted to Sub-Saharan Africa. Here we investigate two independent lines of T. b. rhodesiense that have been selected with the drugs melarsoprol and pentamidine over the course of 2 years, until they exhibited stable cross-resistance to an unprecedented degree. We apply comparative genomics and transcriptomics to identify the underlying mutations. Only few mutations have become fixed during selection. Three genes were affected by mutations in both lines: the aminopurine transporter AT1, the aquaporin AQP2, and the RNA-binding protein UBP1. The melarsoprol-selected line carried a large deletion including the adenosine transporter gene AT1, whereas the pentamidine-selected line carried a heterozygous point mutation in AT1, G430R, which rendered the transporter non-functional. Both resistant lines had lost AQP2, and both lines carried the same point mutation, R131L, in the RNA-binding motif of UBP1. The finding that concomitant deletion of the known resistance genes AT1 and AQP2 in T. b. brucei failed to phenocopy the high levels of resistance of the T. b. rhodesiense mutants indicated a possible role of UBP1 in melarsoprol-pentamidine cross-resistance. However, homozygous in situ expression of UBP1-Leu(131) in T. b. brucei did not affect the sensitivity to melarsoprol or pentamidine.
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Resistencia a Medicamentos/genética , Genoma de Protozoos , Trypanosoma brucei rhodesiense/genética , Secuencia de Aminoácidos , Acuaporinas/genética , Acuaporinas/metabolismo , Hibridación Genómica Comparativa , ADN Protozoario/química , ADN Protozoario/aislamiento & purificación , ADN Protozoario/metabolismo , Heterocigoto , Humanos , Masculino , Melarsoprol/farmacología , Proteínas de Transporte de Nucleósidos/genética , Proteínas de Transporte de Nucleósidos/metabolismo , Pruebas de Sensibilidad Parasitaria , Pentamidina/farmacología , Fenotipo , Polimorfismo de Nucleótido Simple , Proteínas Protozoarias/genética , Proteínas Protozoarias/metabolismo , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismo , Alineación de Secuencia , Tripanocidas/farmacología , Trypanosoma brucei rhodesiense/efectos de los fármacos , Trypanosoma brucei rhodesiense/aislamiento & purificación , Tripanosomiasis Africana/diagnóstico , Tripanosomiasis Africana/parasitologíaRESUMEN
African trypanosomes cause sleeping sickness in humans, a disease that is typically fatal without chemotherapy. Unfortunately, drug resistance is common and melarsoprol-resistant trypanosomes often display cross-resistance to pentamidine. Although melarsoprol/pentamidine cross-resistance (MPXR) has been an area of intense interest for several decades, our understanding of the underlying mechanisms remains incomplete. Recently, a locus encoding two closely related aquaglyceroporins, AQP2 and AQP3, was linked to MPXR in a high-throughput loss-of-function screen. Here, we show that AQP2 has an unconventional "selectivity filter." AQP2-specific gene knockout generated MPXR trypanosomes but did not affect resistance to a lipophilic arsenical, whereas recombinant AQP2 reversed MPXR in cells lacking native AQP2 and AQP3. AQP2 was also shown to be disrupted in a laboratory-selected MPXR strain. Both AQP2 and AQP3 gained access to the surface plasma membrane in insect life-cycle-stage trypanosomes but, remarkably, AQP2 was specifically restricted to the flagellar pocket in the bloodstream stage. We conclude that the unconventional aquaglyceroporin, AQP2, renders cells sensitive to both melarsoprol and pentamidine and that loss of AQP2 function could explain cases of innate and acquired MPXR.
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Acuaporina 2/metabolismo , Melarsoprol/farmacología , Trypanosoma brucei brucei/efectos de los fármacos , Trypanosoma brucei brucei/metabolismo , Tripanosomiasis/tratamiento farmacológico , Tripanosomiasis/parasitología , Animales , Acuaporina 2/genética , Acuaporina 3/genética , Acuaporina 3/metabolismo , Línea Celular , Resistencia a Medicamentos/fisiología , Flagelos/metabolismo , Ensayos Analíticos de Alto Rendimiento , Humanos , Datos de Secuencia Molecular , Pentamidina/farmacología , Tripanocidas/farmacología , Trypanosoma brucei brucei/crecimiento & desarrollo , Tripanosomiasis/metabolismo , Moscas Tse-Tse/parasitologíaRESUMEN
OBJECTIVES: Trypanosoma brucei drug transporters include the TbAT1/P2 aminopurine transporter and the high-affinity pentamidine transporter (HAPT1), but the genetic identity of HAPT1 is unknown. We recently reported that loss of T. brucei aquaglyceroporin 2 (TbAQP2) caused melarsoprol/pentamidine cross-resistance (MPXR) in these parasites and the current study aims to delineate the mechanism by which this occurs. METHODS: The TbAQP2 loci of isogenic pairs of drug-susceptible and MPXR strains of T. brucei subspecies were sequenced. Drug susceptibility profiles of trypanosome strains were correlated with expression of mutated TbAQP2 alleles. Pentamidine transport was studied in T. brucei subspecies expressing TbAQP2 variants. RESULTS: All MPXR strains examined contained TbAQP2 deletions or rearrangements, regardless of whether the strains were originally adapted in vitro or in vivo to arsenicals or to pentamidine. The MPXR strains and AQP2 knockout strains had lost HAPT1 activity. Reintroduction of TbAQP2 in MPXR trypanosomes restored susceptibility to the drugs and reinstated HAPT1 activity, but did not change the activity of TbAT1/P2. Expression of TbAQP2 sensitized Leishmania mexicana promastigotes 40-fold to pentamidine and >1000-fold to melaminophenyl arsenicals and induced a high-affinity pentamidine transport activity indistinguishable from HAPT1 by Km and inhibitor profile. Grafting the TbAQP2 selectivity filter amino acid residues onto a chimeric allele of AQP2 and AQP3 partly restored susceptibility to pentamidine and an arsenical. CONCLUSIONS: TbAQP2 mediates high-affinity uptake of pentamidine and melaminophenyl arsenicals in trypanosomes and TbAQP2 encodes the previously reported HAPT1 activity. This finding establishes TbAQP2 as an important drug transporter.
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Acuagliceroporinas/metabolismo , Resistencia a Medicamentos , Melarsoprol/metabolismo , Pentamidina/metabolismo , Tripanocidas/metabolismo , Trypanosoma brucei brucei/efectos de los fármacos , Trypanosoma brucei brucei/metabolismo , Alelos , Transporte Biológico , Genes Protozoarios , Análisis de Secuencia de ADNRESUMEN
The design, synthesis and structure-activity relationships of a series of oxazole-benzamide inhibitors of the essential bacterial cell division protein FtsZ are described. Compounds had potent anti-staphylococcal activity and inhibited the cytokinesis of the clinically-significant bacterial pathogen Staphylococcus aureus. Selected analogues possessing a 5-halo oxazole also inhibited a strain of S. aureus harbouring the glycine-to-alanine amino acid substitution at residue 196 of FtsZ which conferred resistance to previously reported inhibitors in the series. Substitutions to the pseudo-benzylic carbon of the scaffold improved the pharmacokinetic properties by increasing metabolic stability and provided a mechanism for creating pro-drugs. Combining multiple substitutions based on the findings reported in this study has provided small-molecule inhibitors of FtsZ with enhanced in vitro and in vivo antibacterial efficacy.
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Antibacterianos/farmacología , Proteínas Bacterianas/antagonistas & inhibidores , Benzamidas/farmacología , Proteínas del Citoesqueleto/antagonistas & inhibidores , Diseño de Fármacos , Oxazoles/farmacología , Staphylococcus aureus/efectos de los fármacos , Antibacterianos/síntesis química , Antibacterianos/química , Benzamidas/química , Relación Dosis-Respuesta a Droga , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Oxazoles/química , Staphylococcus aureus/química , Relación Estructura-ActividadRESUMEN
Integrated services which utilise the expertise of team members along care pathways are evolving. Changes in service structure and subsequent team working arrangements can be a challenge for practitioners expected to redefine how they work with one another. These services are particularly important for the care of frail older people. This exploratory study of one newly forming team presents the views of staff involved in establishing an interprofessional healthcare advisory team for older people within an acute hospital admissions unit. Staff experiences of forming a new service are aligned to a model of team development. The findings are presented as themes relating to the stages of team development and identify the challenges of setting up an integrated service alongside existing services. In particular, team process issues relating to the clarity of goals, role clarification, leadership, team culture and identity. Managers must allow time to ensure new services evolve before setting up evaluation studies for efficiency and effectiveness which might prove against the potential for interprofessional teamworking.
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Prestación Integrada de Atención de Salud/organización & administración , Anciano Frágil , Pacientes Internos , Modelos Organizacionales , Grupo de Atención al Paciente/organización & administración , Anciano , Anciano de 80 o más Años , Femenino , Grupos Focales , Objetivos , Humanos , Entrevistas como Asunto , Liderazgo , Masculino , Cultura Organizacional , Rol ProfesionalRESUMEN
INTRODUCTION: Early goal-directed therapy increases survival in persons with sepsis but requires placement of a central line. We evaluate alternative methods to measuring central venous pressure (CVP) to assess volume status, including peripheral venous pressure (PVP) and stroke volume variation (SVV), which may facilitate nurse-driven resuscitation protocols. METHODS: Patients were enrolled in the emergency department or ICU of an academic medical center. Measurements of CVP, PVP, SVV, shoulder and elbow position, and dichotomous variables Awake, Movement, and Vented were measured and recorded 7 times during a 1-hour period. Regression analysis was used to predict CVP from PVP and/or SVV, shoulder/elbow position, and dichotomous variables. RESULTS: Twenty patients were enrolled, of which 20 had PVP measurements and 11 also had SVV measurements. Multiple regression analysis demonstrated significant predictive relationships for CVP using PVP (CVP = 6.7701 + 0.2312 × PVP - 0.1288 × Shoulder + 12.127 × Movement - 4.4805 × Neck line), SVV (CVP = 14.578 - 0.3951 × SVV + 18.113 × Movement), and SVV and PVP (CVP = 4.2997 - 1.1675 × SVV + 0.3866 × PVP + 18.246 × Awake + 0.1467 × Shoulder = 0.4525 × Elbow + 15.472 × Foot line + 10.202 × Arm line). DISCUSSION: PVP and SVV are moderately good predictors of CVP. Combining PVP and SVV and adding variables related to body position, movement, ventilation, and sleep/wake state further improves the predictive value of the model. The models illustrate the importance of standardizing patient position, minimizing movement, and placing intravenous lines proximally in the upper extremity or neck.
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Presión Venosa Central/fisiología , Hemodinámica/fisiología , Sepsis/fisiopatología , Volumen Sistólico/fisiología , Presión Venosa/fisiología , Centros Médicos Académicos , Adulto , Anciano , Análisis de Varianza , Determinación del Volumen Sanguíneo/métodos , Cateterismo Periférico/métodos , Cuidados Críticos/métodos , Enfermedad Crítica/mortalidad , Enfermedad Crítica/terapia , Educación Continua en Enfermería , Servicio de Urgencia en Hospital , Femenino , Mortalidad Hospitalaria , Humanos , Unidades de Cuidados Intensivos , Masculino , Persona de Mediana Edad , Monitoreo Fisiológico , Valor Predictivo de las Pruebas , Análisis de Regresión , Sensibilidad y Especificidad , Sepsis/mortalidad , Sepsis/terapia , Adulto JovenRESUMEN
Long COVID is a common sequela of SARS-CoV-2 infection. Data from numerous scientific studies indicate that long COVID involves a complex interaction between pathophysiological processes. Long COVID may involve the development of new diagnosable health conditions and exacerbation of pre-existing health conditions. However, despite this rapidly accumulating body of evidence regarding the pathobiology of long COVID, psychogenic and functional interpretations of the illness presentation continue to be endorsed by some healthcare professionals, creating confusion and inappropriate diagnostic and therapeutic pathways for people living with long COVID. The purpose of this perspective is to present a clinical and scientific rationale for why long COVID should not be considered as a functional neurologic disorder. It will begin by discussing the parallel historical development of pathobiological and psychosomatic/sociogenic diagnostic constructs arising from a common root in neurasthenia, which has resulted in the collective understandings of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) and functional neurologic disorder (FND), respectively. We will also review the case definition criteria for FND and the distinguishing clinical and neuroimaging findings in FND vs. long COVID. We conclude that considering long COVID as FND is inappropriate based on differentiating pathophysiologic mechanisms and distinguishing clinical findings.
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The bacterial cell division protein FtsZ is an attractive target for small-molecule antibacterial drug discovery. Derivatives of 3-methoxybenzamide, including compound PC190723, have been reported to be potent and selective antistaphylococcal agents which exert their effects through the disruption of intracellular FtsZ function. Here, we report the further optimization of 3-methoxybenzamide derivatives towards a drug candidate. The in vitro and in vivo characterization of a more advanced lead compound, designated compound 1, is described. Compound 1 was potently antibacterial, with an average MIC of 0.12 µg/ml against all staphylococcal species, including methicillin- and multidrug-resistant Staphylococcus aureus and Staphylococcus epidermidis. Compound 1 inhibited an S. aureus strain carrying the G196A mutation in FtsZ, which confers resistance to PC190723. Like PC190723, compound 1 acted on whole bacterial cells by blocking cytokinesis. No interactions between compound 1 and a diverse panel of antibiotics were measured in checkerboard experiments. Compound 1 displayed suitable in vitro pharmaceutical properties and a favorable in vivo pharmacokinetic profile following intravenous and oral administration, with a calculated bioavailability of 82.0% in mice. Compound 1 demonstrated efficacy in a murine model of systemic S. aureus infection and caused a significant decrease in the bacterial load in the thigh infection model. A greater reduction in the number of S. aureus cells recovered from infected thighs, equivalent to 3.68 log units, than in those recovered from controls was achieved using a succinate prodrug of compound 1, which was designated compound 2. In summary, optimized derivatives of 3-methoxybenzamide may yield a first-in-class FtsZ inhibitor for the treatment of antibiotic-resistant staphylococcal infections.
Asunto(s)
Antibacterianos/farmacocinética , Proteínas Bacterianas/antagonistas & inhibidores , Benzamidas/farmacocinética , Proteínas del Citoesqueleto/antagonistas & inhibidores , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Oxazoles/farmacocinética , Profármacos/farmacocinética , Infecciones Estafilocócicas/tratamiento farmacológico , Staphylococcus epidermidis/efectos de los fármacos , Succinatos/farmacocinética , Administración Oral , Animales , Antibacterianos/síntesis química , Antibacterianos/farmacología , Proteínas Bacterianas/genética , Benzamidas/síntesis química , Benzamidas/química , Benzamidas/farmacología , Disponibilidad Biológica , Recuento de Colonia Microbiana , Citocinesis/efectos de los fármacos , Proteínas del Citoesqueleto/genética , Farmacorresistencia Bacteriana Múltiple , Femenino , Inyecciones Intravenosas , Staphylococcus aureus Resistente a Meticilina/genética , Staphylococcus aureus Resistente a Meticilina/crecimiento & desarrollo , Ratones , Pruebas de Sensibilidad Microbiana , Mutación , Oxazoles/síntesis química , Oxazoles/farmacología , Profármacos/síntesis química , Profármacos/farmacología , Infecciones Estafilocócicas/microbiología , Staphylococcus epidermidis/crecimiento & desarrollo , Succinatos/síntesis química , Succinatos/farmacología , Ácido Succínico/química , Muslo/microbiología , Resultado del TratamientoRESUMEN
The trypanosomes cause two neglected tropical diseases, Chagas disease in the Americas and African trypanosomiasis in sub-Saharan Africa. Over recent years a raft of molecular tools have been developed enabling the genetic dissection of many aspects of trypanosome biology, including the mechanisms underlying resistance to some of the current clinical and veterinary drugs. This has led to the identification and characterization of key resistance determinants, including transporters for the anti-Trypanosoma brucei drugs, melarsoprol, pentamidine and eflornithine, and the activator of nifurtimox-benznidazole, the anti-Trypanosoma cruzi drugs. More recently, advances in sequencing technology, combined with the development of RNA interference libraries in the clinically relevant bloodstream form of T. brucei have led to an exponential increase in the number of proteins known to interact either directly or indirectly with the anti-trypanosomal drugs. In this review, we discuss these findings and the technological developments that are set to further revolutionise our understanding of drug-trypanosome interactions. The new knowledge gained should inform the development of novel interventions against the devastating diseases caused by these parasites.
Asunto(s)
Enfermedad de Chagas/parasitología , Resistencia a Medicamentos/genética , Tripanocidas/farmacología , Trypanosoma brucei brucei/genética , Trypanosoma cruzi/genética , Tripanosomiasis Africana/parasitología , Animales , Humanos , Enfermedades Desatendidas/parasitología , Interferencia de ARN , Análisis de Secuencia de ADN , Tripanocidas/química , Trypanosoma brucei brucei/efectos de los fármacos , Trypanosoma cruzi/efectos de los fármacosRESUMEN
Energy relay dyes (ERD) and Förster resonant energy transfer (FRET) are useful techniques for increasing absorption in dye-sensitized solar cells. We use femtosecond transient absorption spectroscopy to monitor charge generation processes in a solid-state DSC containing poly(3-hexylthiophene) (P3HT) as both the hole-transporter and the ERD with a zinc phthalocyanine dye (TT1) as the sensitizer. We observe efficient FRET occurring on picosecond time scales and subsequent hole transfer from TT1 to P3HT occurring onward from 100 ps.
Asunto(s)
Colorantes Fluorescentes/química , Energía Solar , Tiofenos/química , Suministros de Energía Eléctrica , Transferencia Resonante de Energía de Fluorescencia , Estructura Molecular , Factores de TiempoRESUMEN
BACKGROUND: Myalgic encephalomyelitis (ME) is a complex, multi-system neurological condition. The defining feature of ME is post-exertional malaise (PEM) with over 30 symptoms triggered by physical, cognitive, emotional and social activity. The cause of PEM is unclear but one area of research using cardio-pulmonary exercise tests show a reduced ventilatory anaerobic threshold (VAT) with repeated tests leading to PEM. Pacing with heart rate monitoring (HRM) provides feedback to maintain activity intensity below the VAT. There is only one piece of research investigating the use of HRM although a number of guidelines recommend it. OBJECTIVE: To identify the experiences and attitudes of people with ME towards HRM. METHODS: A 40 question online survey was devised and released on ME websites, Twitter and Facebook pages. People with ME read the information sheet and followed an online link to the survey. The survey was open for three weeks and all answers were anonymous. RESULTS: 488 people with ME completed the survey. Most participants were female, 35-50 years and with a reported illness of greater than 5 years. Over 100 types of HR monitor used. Over 30 benefits and over 30 negatives identified. HRM reduced severity of ME and severity and duration of PEM. CONCLUSION: Although there are limitations, HRM has many benefits including helping PwME to understand and manage their PEM and support them to increase their activities, including work. There is a need for more research and education of healthcare professionals in the safe use of HRM.
Asunto(s)
Síndrome de Fatiga Crónica , Humanos , Femenino , Masculino , Frecuencia Cardíaca , Encuestas y Cuestionarios , Prueba de Esfuerzo , ActitudRESUMEN
Blastocystis is the most prevalent microbial eukaryote in the human and animal gut, yet its role as commensal or parasite is still under debate. Blastocystis has clearly undergone evolutionary adaptation to the gut environment and possesses minimal cellular compartmentalization, reduced anaerobic mitochondria, no flagella, and no reported peroxisomes. To address this poorly understood evolutionary transition, we have taken a multi-disciplinary approach to characterize Proteromonas lacertae, the closest canonical stramenopile relative of Blastocystis. Genomic data reveal an abundance of unique genes in P. lacertae but also reductive evolution of the genomic complement in Blastocystis. Comparative genomic analysis sheds light on flagellar evolution, including 37 new candidate components implicated with mastigonemes, the stramenopile morphological hallmark. The P. lacertae membrane-trafficking system (MTS) complement is only slightly more canonical than that of Blastocystis, but notably, we identified that both organisms encode the complete enigmatic endocytic TSET complex, a first for the entire stramenopile lineage. Investigation also details the modulation of mitochondrial composition and metabolism in both P. lacertae and Blastocystis. Unexpectedly, we identify in P. lacertae the most reduced peroxisome-derived organelle reported to date, which leads us to speculate on a mechanism of constraint guiding the dynamics of peroxisome-mitochondrion reductive evolution on the path to anaerobiosis. Overall, these analyses provide a launching point to investigate organellar evolution and reveal in detail the evolutionary path that Blastocystis has taken from a canonical flagellated protist to the hyper-divergent and hyper-prevalent animal and human gut microbe.