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1.
Nephrol Dial Transplant ; 38(11): 2576-2588, 2023 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-37120733

RESUMEN

BACKGROUND: Light chain proximal tubulopathy (LCPT) is a rare form of paraprotein-related disease, occurring in two main histopathological forms: crystalline and non-crystalline. The clinicopathological features, treatment strategies and outcomes, especially of the non-crystalline form, are not well described. METHODS: We conducted a single-centre retrospective case series of 12 LCPT patients, 5 crystalline and 7 non-crystalline, between 2005 and 2021. RESULTS: The median age was 69.5 years (range 47-80). Ten patients presented with CKD and significant proteinuria (median estimated glomerular filtration rate of 43.5 ml/min/1.73 m2; urine protein:creatinine ratio 328 mg/mmol). Only six patients had known haematological disease at the time of renal biopsy. Multiple myeloma (MM) was diagnosed in seven patients cases and monoclonal gammopathy of renal significance (MGRS) in five patients. A clone was detected in all cases combining serum/urine electrophoresis and free light chain (LC) assays. Crystalline and non-crystalline variants had similar clinical presentations. For the non-crystalline variant, a diagnosis was reached based on a combination of CKD without another cause, haematological workup, LC restriction on immunofluorescence and abnormalities on electron microscopy (EM). Nine of 12 patients received clone-directed treatment. Patients who achieved haematological response (including all non-crystalline LCPT) had improved renal outcomes over a median follow-up of 79 months. CONCLUSIONS: The non-crystalline variant may go unrecognised because of its subtle histopathological features and requires EM to distinguish it from 'excessive LC resorption without tubular injury'. Clone-directed treatment with good haematological response improves renal outcomes in both variants but limited data exist in MGRS. Multicentre prospective studies are needed to better define the clinicopathological characteristics associated with poor outcomes and optimize treatment strategies in patients with MGRS.


Asunto(s)
Enfermedades Renales , Mieloma Múltiple , Paraproteinemias , Insuficiencia Renal Crónica , Humanos , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Estudios Retrospectivos , Enfermedades Renales/patología , Riñón/patología , Mieloma Múltiple/diagnóstico , Mieloma Múltiple/complicaciones , Cadenas Ligeras de Inmunoglobulina/análisis , Insuficiencia Renal Crónica/complicaciones , Paraproteinemias/diagnóstico , Paraproteinemias/complicaciones , Paraproteinemias/patología
2.
BJOG ; 130(4): 377-386, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36371677

RESUMEN

OBJECTIVE: To elaborate the associations of different cycle regimens (natural cycle [NC], stimulated cycle [SC], hormone replacement cycle [HRC]) on maternal and neonatal adverse pregnancy outcomes after frozen-thawed embryo transfers (FET). DESIGN: Population-based registry study. SETTING: Swiss IVF Registry. POPULATION OR SAMPLE: Singleton (n = 4636) and twin (n = 544) live births after NC-FET (n = 776), SC-FET (n = 758) or HRC-FET (n = 3646) registered from 2014 to 2019. METHODS: Fifteen pregnancy pathologies were modelled for singleton and twin pregnancies using mixed models adjusted for cycle regimen, delivery, fertilisation technique, chronic anovulation, age of mother and centre. MAIN OUTCOME MEASURES: Maternal (vaginal bleeding, isolated arterial hypertension and pre-eclampsia) and neonatal (gestational age, birthweight, mode of delivery) adverse pregnancy outcomes. RESULTS: In singleton pregnancies, the incidences of bleeding in first trimester, isolated hypertension and pre-eclampsia were highest in HRC-FET with doubled odds of bleeding in first trimester (adjusted odds ratio [aOR] 2.23; 95% CI 1.33-3.75), isolated hypertension (aOR 2.50; 95% CI 1.02-6.12) and pre-eclampsia (aOR 2.16; 95% CI 1.13-4.12) in HRC-FET vs. NC-FET and with doubled respectively sixfold odds of bleeding (aOR 2.08; 95% CI 1.03-4.21) and pre-eclampsia (6.02; 95% CI 1.38-26.24) in HRC-FET versus SC-FET. In twin pregnancies, the incidence of pre-eclampsia was highest in HRC-FET with numerically higher odds of pre-eclampsia in HRC-FET versus NC-FET and versus SC-FET. CONCLUSIONS: Our data implied the highest maternal risks of hypertensive disorders in HRC-FET, therefore clinicians should prefer SC-FET or NC-FET if medically possible.


Asunto(s)
Hipertensión Inducida en el Embarazo , Preeclampsia , Embarazo , Recién Nacido , Femenino , Humanos , Embarazo Gemelar , Preeclampsia/epidemiología , Hipertensión Inducida en el Embarazo/epidemiología , Hipertensión Inducida en el Embarazo/etiología , Estudios Retrospectivos , Hormonas , Criopreservación/métodos
3.
Nano Lett ; 22(15): 6062-6068, 2022 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-35862274

RESUMEN

Recent reports of superconductivity at KTaO3 (KTO) (110) and (111) interfaces have sparked intense interest due to the relatively high critical temperature as well as other properties that distinguish this system from the more extensively studied SrTiO3 (STO)-based heterostructures. Here, we report the reconfigurable creation of conducting structures at intrinsically insulating LaAlO3/KTO(110) and (111) interfaces. Devices are created using two distinct methods previously developed for STO-based heterostructures: (1) conductive atomic-force microscopy lithography and (2) ultralow-voltage electron-beam lithography. At low temperatures, KTO(110)-based devices show superconductivity that is tunable by an applied back gate. A one-dimensional nanowire device shows single-electron-transistor (SET) behavior. A KTO(111)-based device is metallic but does not become superconducting. These reconfigurable methods of creating nanoscale devices in KTO-based heterostructures offer new avenues for investigating mechanisms of superconductivity as well as development of quantum devices that incorporate strong spin-orbit interactions, superconducting behavior, and nanoscale dimensions.

4.
Genome Res ; 29(7): 1152-1163, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31235654

RESUMEN

Genomes and transcriptomes are now typically sequenced by individual laboratories but analyzing them often remains challenging. One essential step in many analyses lies in identifying orthologs-corresponding genes across multiple species-but this is far from trivial. The Orthologous MAtrix (OMA) database is a leading resource for identifying orthologs among publicly available, complete genomes. Here, we describe the OMA pipeline available as a standalone program for Linux and Mac. When run on a cluster, it has native support for the LSF, SGE, PBS Pro, and Slurm job schedulers and can scale up to thousands of parallel processes. Another key feature of OMA standalone is that users can combine their own data with existing public data by exporting genomes and precomputed alignments from the OMA database, which currently contains over 2100 complete genomes. We compare OMA standalone to other methods in the context of phylogenetic tree inference, by inferring a phylogeny of Lophotrochozoa, a challenging clade within the protostomes. We also discuss other potential applications of OMA standalone, including identifying gene families having undergone duplications/losses in specific clades, and identifying potential drug targets in nonmodel organisms. OMA standalone is available under the permissive open source Mozilla Public License Version 2.0.


Asunto(s)
Bases de Datos Genéticas , Genoma , Invertebrados/clasificación , Programas Informáticos , Transcriptoma , Animales , Invertebrados/genética , Filogenia
5.
Rheumatology (Oxford) ; 61(5): 2088-2094, 2022 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-34554243

RESUMEN

OBJECTIVES: To evaluate the long-term efficacy and safety of canakinumab in patients with mevalonate kinase deficiency during the open label extension (weeks 41-113) of the randomized controlled CLUSTER trial. METHODS: During a 72-week period, patients received open-label canakinumab 150 or 300 mg, every 4 or 8 weeks. The disease activity was evaluated every 8 weeks using physician global assessment and counting the number of flares. Concentrations of CRP and serum amyloid A protein were measured. The safety was studied by determination and classification of observed adverse events. The safety and efficacy were analysed separately in three subgroups of patients receiving a cumulative dose of less than <35 mg/kg, ≥35 to <70 mg/kg or ≥70 mg/kg. RESULTS: Of the 74 patients who started the CLUSTER study, 66 entered Epoch 4 and 65 completed it. During the 72-week period, 42 (64%) patients experienced no flares, while 13 (20%) had one flare, as compared with a median of 12 flares per year reported at baseline. Low physician global assessment scores were seen at the end of the study for all groups with >90% reporting minimal disease activity or none at all. Median CRP concentrations were consistently equal or lower than 10 mg/l, while median serum amyloid A concentrations remained only slightly above the normal range of 10 mg/l. The study showed no new or unexpected adverse events. CONCLUSION: Canakinumab proved effective to control disease activity and prevent flares in mevalonate kinase deficiency during the 72-week study period. No new safety concerns were reported. TRIAL REGISTRATION: NCT02059291. https://clinicaltrials.gov.


Asunto(s)
Deficiencia de Mevalonato Quinasa , Anticuerpos Monoclonales/efectos adversos , Anticuerpos Monoclonales Humanizados/efectos adversos , Método Doble Ciego , Humanos , Deficiencia de Mevalonato Quinasa/tratamiento farmacológico , Proteína Amiloide A Sérica , Resultado del Tratamiento
6.
Kidney Int ; 100(6): 1316-1324, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34560140

RESUMEN

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis can present with life-threatening lung-kidney syndromes. However, many controlled treatment trials excluded patients with diffuse alveolar hemorrhage or severely impaired glomerular filtration rates, and so the optimum treatment in these cases is unclear. In this retrospective cohort study, we report the outcomes of 64 patients with life-threatening disease treated with a combination regimen of rituximab, low-dose intravenous cyclophosphamide, oral glucocorticoids, and plasma exchange. At entry, the median estimated glomerular filtration rate was 9 mL/min, 47% of patients required dialysis, and 52% had diffuse alveolar hemorrhage. All patients received a minimum of seven plasma exchanges, and the median cumulative doses of rituximab, cyclophosphamide, and glucocorticoid were 2, 3, and 2.6 g, respectively, at six months. A total of 94% of patients had achieved disease remission (version 3 Birmingham Vasculitis Activity Score of 0) at this time point, and 67% of patients who required dialysis recovered independent kidney function. During long-term follow-up (median duration 46 months), overall patient survival was 85%, and 69% of patients remained free from end-stage kidney disease, which compares favorably to a historic cohort with severe disease treated with a conventional induction regimen. Combination treatment was associated with prolonged B cell depletion and low rates of relapse; 87% of patients were in continuous remission at month 36. The serious infection rate during total follow-up was 0.28 infections/patient/year, suggesting that combination treatment is not associated with an enduring risk of infection. Thus, we suggest that combination immunosuppressive therapy may permit glucocorticoid avoidance and provide rapid and prolonged disease control in patients with severe ANCA-associated vasculitis.


Asunto(s)
Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos , Anticuerpos Anticitoplasma de Neutrófilos , Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos/tratamiento farmacológico , Ciclofosfamida/efectos adversos , Quimioterapia Combinada , Humanos , Inmunosupresores/efectos adversos , Intercambio Plasmático , Inducción de Remisión , Estudios Retrospectivos , Rituximab/efectos adversos
7.
Nature ; 521(7551): 196-9, 2015 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-25971511

RESUMEN

Strontium titanate (SrTiO3) is the first and best known superconducting semiconductor. It exhibits an extremely low carrier density threshold for superconductivity, and possesses a phase diagram similar to that of high-temperature superconductors--two factors that suggest an unconventional pairing mechanism. Despite sustained interest for 50 years, direct experimental insight into the nature of electron pairing in SrTiO3 has remained elusive. Here we perform transport experiments with nanowire-based single-electron transistors at the interface between SrTiO3 and a thin layer of lanthanum aluminate, LaAlO3. Electrostatic gating reveals a series of two-electron conductance resonances-paired electron states--that bifurcate above a critical pairing field Bp of about 1-4 tesla, an order of magnitude larger than the superconducting critical magnetic field. For magnetic fields below Bp, these resonances are insensitive to the applied magnetic field; for fields in excess of Bp, the resonances exhibit a linear Zeeman-like energy splitting. Electron pairing is stable at temperatures as high as 900 millikelvin, well above the superconducting transition temperature (about 300 millikelvin). These experiments demonstrate the existence of a robust electronic phase in which electrons pair without forming a superconducting state. Key experimental signatures are captured by a model involving an attractive Hubbard interaction that describes real-space electron pairing as a precursor to superconductivity.

8.
Nano Lett ; 20(10): 6966-6973, 2020 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-32870015

RESUMEN

We explore the ultrafast optical response of graphene subjected to intense (∼106 V/cm) local (∼10 nm) electric fields. Nanoscale gating of graphene is achieved using a voltage-biased, SrTiO3-based conductive nanowire junction "written" directly under the graphene and isolated from it by an insulating ultrathin (<2 nm) LaAlO3 barrier. Upon illumination with ultrafast visible-to-near-infrared (VIS-NIR) light pulses, the local field from the nanojunction creates a strong gate-tunable second-order nonlinearity in the graphene and produces a substantial difference-frequency (DFG) and sum-frequency generation (SFG) response detected by the nanojunction. Spectrally sharp, gate-tunable extinction features (>99.9%) are observed in the VIS-NIR and SFG spectral ranges, in parameter regimes that are positively correlated with the enhanced nonlinear response. The observed graphene-light interaction and nonlinear response are of fundamental interest and open the way for future exploitation in graphene-based optical devices such as phase shifters, modulators, and nanoscale THz sources.

9.
Rheumatology (Oxford) ; 58(2): 260-268, 2019 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-30239910

RESUMEN

Objectives: Glucocorticoids (GCs) are a mainstay of treatment for patients with ANCA-associated vasculitis (AAV) but are associated with significant adverse effects. Effective remission induction in severe AAV using extremely limited GC exposure has not been attempted. We tested an early rapid GC withdrawal induction regimen for patients with severe AAV. Methods: Patients with active MPO- or PR3-ANCA vasculitis or ANCA-negative pauci-immune glomerulonephritis were included. Induction treatment consisted of two doses of rituximab, 3 months of low-dose CYC and a short course of oral GC (for between 1 and 2 weeks). Clinical, biochemical and immunological outcomes as well as adverse events were recorded. Results: A total of 49 patients were included, with at least 12 months of follow-up in 46. All patients achieved remission, with decreases observed in creatinine, proteinuria, CRP, ANCA level and BVAS. Three patients requiring dialysis at presentation became dialysis independent. Two patients required the introduction of maintenance GC for treatment of vasculitis. Overall outcomes were comparable to those of two matched cohorts (n = 172) from previous European Vasculitis Society (EUVAS) trials, but with lower total exposure to CYC and GCs (P < 0.001) and reduced rates of severe infections (P = 0.02) compared with the RITUXVAS (rituximab versus cyclophosphamide in AAV) trial. We found no new cases of diabetes in the first year compared with historic rates of 8.2% from the EUVAS trials (P = 0.04). Conclusion: Early GC withdrawal in severe AAV is as effective for remission induction as the standard of care and is associated with reduced GC-related adverse events.


Asunto(s)
Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos/tratamiento farmacológico , Glucocorticoides/administración & dosificación , Enfermedad Aguda , Administración Oral , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Ciclofosfamida/administración & dosificación , Ciclofosfamida/efectos adversos , Ciclofosfamida/uso terapéutico , Esquema de Medicación , Quimioterapia Combinada , Femenino , Estudios de Seguimiento , Glucocorticoides/efectos adversos , Glucocorticoides/uso terapéutico , Humanos , Inmunosupresores/administración & dosificación , Inmunosupresores/efectos adversos , Inmunosupresores/uso terapéutico , Masculino , Persona de Mediana Edad , Recurrencia , Inducción de Remisión , Rituximab/administración & dosificación , Rituximab/efectos adversos , Rituximab/uso terapéutico , Índice de Severidad de la Enfermedad , Resultado del Tratamiento , Adulto Joven
10.
Nephrol Dial Transplant ; 34(1): 63-73, 2019 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-29462348

RESUMEN

Background: Current guidelines advise that rituximab or cyclophosphamide should be used for the treatment of organ-threatening disease in anti-neutrophil cytoplasm antibody (ANCA)-associated vasculitis (AAV), although few studies have examined the efficacy and safety of these agents in combination. Methods: We conducted a single-centre cohort study of 66 patients treated with a combination of oral corticosteroids, rituximab and low-dose pulsed intravenous cyclophosphamide followed by a maintenance regimen of azathioprine and tapered steroid for the treatment of biopsy-proven renal involvement in AAV. Patients were followed for a median of 56 months. Case-control analysis with 198 propensity-matched cases from European Vasculitis Study Group (EUVAS) trials compared long-term differences in relapse-free, renal and patient survival. Results: At entry, the median Birmingham Vasculitis Activity Score (BVAS) was 19 and estimated glomerular filtration rate was 25 mL/min. Cumulative doses of rituximab, cyclophosphamide and corticosteroids were 2, 3 and 4.2 g, respectively, at 6 months. A total of 94% of patients achieved disease remission by 6 months (BVAS < 0) and patient and renal survival were 84 and 95%, respectively, at 5 years. A total of 84% achieved ANCA-negative status and 57% remained B cell deplete at 2 years, which was associated with low rates of major relapse (15% at 5 years). The serious infection rate during long-term follow-up was 1.24 per 10 patient-years. Treatment with this regimen was associated with a reduced risk of death {hazard ratio [HR] 0.29 [95% confidence interval (CI) 0.125-0.675], P = 0.004}, progression to end-stage renal disease (ESRD) [HR 0.20 (95% CI 0.06-0.65), P = 0.007] and relapse [HR 0.49 (95% CI 0.25-0.97), P = 0.04] compared with propensity-matched patients enrolled in EUVAS trials. Conclusions: This regimen is potentially superior to current standards of care, and controlled studies are warranted to establish the utility of combination drug approaches in the treatment of AAV.


Asunto(s)
Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos/tratamiento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Enfermedades Renales/tratamiento farmacológico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Azatioprina/administración & dosificación , Estudios de Casos y Controles , Estudios de Cohortes , Ciclofosfamida/administración & dosificación , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Tasa de Filtración Glomerular , Humanos , Fallo Renal Crónico/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Pronóstico , Inducción de Remisión , Rituximab/administración & dosificación , Tasa de Supervivencia , Adulto Joven
11.
BMC Gastroenterol ; 19(1): 156, 2019 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-31462210

RESUMEN

BACKGROUND: Haemolytic uraemic syndrome is a rarely seen in adults often leading to critical illness. This case highlights how difficult it can be to establish a diagnosis and treat when a patient presents with bloody diarrhoea. CASE PRESENTATION: A 17-year-old Iraqi man presented to the emergency department with abdominal pain and bloody diarrhoea. He was initially treated as acute appendicitis, undergoing an appendectomy but following a recurrence in his symptoms a colonoscopy was performed. A diagnosis of shiga toxin-producing Escherichia coli leading to HUS was suspected following histology obtained at colonoscopy and this was confirmed on antibody testing. Despite intravenous fluids and supportive therapy the patient's symptoms and condition deteriorated. He developed seizures and acute renal failure requiring intubation and plasma exchange in the intensive care setting. He eventually required treatment with ecluzimab therapy; a monoclonal antibody and subsequently made a full recovery. CONCLUSIONS: Haemolytic uraemic syndrome is a triad of progressive renal failure, thrombocytopenia and haemolytic anaemia which is a condition rarely seen in adults. It is usually associated with an E. coli infection and supportive therapy remains the mainstay of treatment.


Asunto(s)
Infecciones por Escherichia coli/diagnóstico , Síndrome Hemolítico-Urémico/diagnóstico , Lesión Renal Aguda/etiología , Lesión Renal Aguda/terapia , Adolescente , Colonoscopía , Diarrea/etiología , Infecciones por Escherichia coli/complicaciones , Infecciones por Escherichia coli/patología , Infecciones por Escherichia coli/terapia , Escherichia coli O157 , Fluidoterapia , Hemorragia Gastrointestinal/etiología , Síndrome Hemolítico-Urémico/etiología , Síndrome Hemolítico-Urémico/patología , Síndrome Hemolítico-Urémico/terapia , Humanos , Intubación Intratraqueal , Masculino , Intercambio Plasmático , Convulsiones/etiología
12.
BMC Nephrol ; 20(1): 352, 2019 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-31492152

RESUMEN

BACKGROUND: Tacrolimus (TAC) is effective in treating membranous nephropathy (MN); however relapses are frequent after treatment cessation. We conducted a randomised controlled trial to examine whether the addition of mycophenolate mofetil (MMF) to TAC would reduce relapse rate. METHODS: Forty patients with biopsy proven idiopathic MN and nephrotic syndrome were randomly assigned to receive either TAC monotherapy (n = 20) or TAC combined with MMF (n = 20) for 12 months. When patients had been in remission for 1 year on treatment the MMF was stopped and the TAC gradually withdrawn in both groups over 6 months. Patients also received supportive treatment with angiotensin blockade, statins, diuretics and anticoagulation as needed. Primary endpoint was relapse rate following treatment withdrawal. Secondary outcomes were remission rate, time to remission and change in renal function. RESULTS: 16/20 (80%) of patients in the TAC group achieved remission compared to 19/20 (95%) in the TAC/MMF group (p = 0.34). The median time to remission in the TAC group was 54 weeks compared to 40 weeks in the TAC/MMF group (p = 0.46). There was no difference in the relapse rate between the groups: 8/16 (50%) patients in the TAC group relapsed compared to 8/19 (42%) in the TAC/MMF group (p = 0.7). The addition of MMF to TAC did not adversely affect the safety of the treatment. CONCLUSIONS: Addition of MMF to TAC does not alter the relapse rate of nephrotic syndrome in patients with MN. TRIAL REGISTRATION: This trial is registered with EudraCTN2008-001009-41 . Trial registration date 2008-10-08.


Asunto(s)
Glomerulonefritis Membranosa/diagnóstico , Glomerulonefritis Membranosa/tratamiento farmacológico , Inmunosupresores/administración & dosificación , Ácido Micofenólico/administración & dosificación , Tacrolimus/administración & dosificación , Adulto , Anciano , Quimioterapia Combinada , Femenino , Glomerulonefritis Membranosa/sangre , Humanos , Masculino , Persona de Mediana Edad , Recurrencia , Inducción de Remisión/métodos , Adulto Joven
13.
BMC Nephrol ; 20(1): 379, 2019 10 17.
Artículo en Inglés | MEDLINE | ID: mdl-31623578

RESUMEN

This guideline is written primarily for doctors and nurses working in dialysis units and related areas of medicine in the UK, and is an update of a previous version written in 2009. It aims to provide guidance on how to look after patients and how to run dialysis units, and provides standards which units should in general aim to achieve. We would not advise patients to interpret the guideline as a rulebook, but perhaps to answer the question: "what does good quality haemodialysis look like?"The guideline is split into sections: each begins with a few statements which are graded by strength (1 is a firm recommendation, 2 is more like a sensible suggestion), and the type of research available to back up the statement, ranging from A (good quality trials so we are pretty sure this is right) to D (more like the opinion of experts than known for sure). After the statements there is a short summary explaining why we think this, often including a discussion of some of the most helpful research. There is then a list of the most important medical articles so that you can read further if you want to - most of this is freely available online, at least in summary form.A few notes on the individual sections: 1. This section is about how much dialysis a patient should have. The effectiveness of dialysis varies between patients because of differences in body size and age etc., so different people need different amounts, and this section gives guidance on what defines "enough" dialysis and how to make sure each person is getting that. Quite a bit of this section is very technical, for example, the term "eKt/V" is often used: this is a calculation based on blood tests before and after dialysis, which measures the effectiveness of a single dialysis session in a particular patient. 2. This section deals with "non-standard" dialysis, which basically means anything other than 3 times per week. For example, a few people need 4 or more sessions per week to keep healthy, and some people are fine with only 2 sessions per week - this is usually people who are older, or those who have only just started dialysis. Special considerations for children and pregnant patients are also covered here. 3. This section deals with membranes (the type of "filter" used in the dialysis machine) and "HDF" (haemodiafiltration) which is a more complex kind of dialysis which some doctors think is better. Studies are still being done, but at the moment we think it's as good as but not better than regular dialysis. 4. This section deals with fluid removal during dialysis sessions: how to remove enough fluid without causing cramps and low blood pressure. Amongst other recommendations we advise close collaboration with patients over this. 5. This section deals with dialysate, which is the fluid used to "pull" toxins out of the blood (it is sometimes called the "bath"). The level of things like potassium in the dialysate is important, otherwise too much or too little may be removed. There is a section on dialysate buffer (bicarbonate) and also a section on phosphate, which occasionally needs to be added into the dialysate. 6. This section is about anticoagulation (blood thinning) which is needed to stop the circuit from clotting, but sometimes causes side effects. 7. This section is about certain safety aspects of dialysis, not seeking to replace well-established local protocols, but focussing on just a few where we thought some national-level guidance would be useful. 8. This section draws together a few aspects of dialysis which don't easily fit elsewhere, and which impact on how dialysis feels to patients, rather than the medical outcome, though of course these are linked. This is where home haemodialysis and exercise are covered. There is an appendix at the end which covers a few aspects in more detail, especially the mathematical ideas. Several aspects of dialysis are not included in this guideline since they are covered elsewhere, often because they are aspects which affect non-dialysis patients too. This includes: anaemia, calcium and bone health, high blood pressure, nutrition, infection control, vascular access, transplant planning, and when dialysis should be started.


Asunto(s)
Instituciones de Atención Ambulatoria/normas , Soluciones para Diálisis/normas , Diálisis Renal/normas , Insuficiencia Renal/terapia , Anticoagulantes/administración & dosificación , Soluciones para Diálisis/química , Humanos , Membranas Artificiales , Diálisis Renal/efectos adversos , Diálisis Renal/métodos , Reino Unido
14.
Nano Lett ; 18(7): 4473-4481, 2018 07 11.
Artículo en Inglés | MEDLINE | ID: mdl-29924620

RESUMEN

SrTiO3-based heterointerfaces support quasi-two-dimensional (2D) electron systems that are analogous to III-V semiconductor heterostructures, but also possess superconducting, magnetic, spintronic, ferroelectric, and ferroelastic degrees of freedom. Despite these rich properties, the relatively low mobilities of 2D complex-oxide interfaces appear to preclude ballistic transport in 1D. Here we show that the 2D LaAlO3/SrTiO3 interface can support quantized ballistic transport of electrons and (nonsuperconducting) electron pairs within quasi-1D structures that are created using a well-established conductive atomic-force microscope (c-AFM) lithography technique. The nature of transport ranges from truly single-mode (1D) to three-dimensional (3D), depending on the applied magnetic field and gate voltage. Quantization of the lowest e2/ h plateau indicate a ballistic mean-free path lMF ∼ 20 µm, more than 2 orders of magnitude larger than for 2D LaAlO3/SrTiO3 heterostructures. Nonsuperconducting electron pairs are found to be stable in magnetic fields as high as B = 11 T and propagate ballistically with conductance quantized at 2 e2/ h. Theories of one-dimensional (1D) transport of interacting electron systems depend crucially on the sign of the electron-electron interaction, which may help explain the highly ballistic transport behavior. The 1D geometry yields new insights into the electronic structure of the LaAlO3/SrTiO3 system and offers a new platform for the study of strongly interacting 1D electronic systems.

15.
Rep Prog Phys ; 81(3): 036503, 2018 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-29424362

RESUMEN

This review provides a summary of the rich physics expressed within SrTiO3-based heterostructures and nanostructures. The intended audience is researchers who are working in the field of oxides, but also those with different backgrounds (e.g., semiconductor nanostructures). After reviewing the relevant properties of SrTiO3 itself, we will then discuss the basics of SrTiO3-based heterostructures, how they can be grown, and how devices are typically fabricated. Next, we will cover the physics of these heterostructures, including their phase diagram and coupling between the various degrees of freedom. Finally, we will review the rich landscape of quantum transport phenomena, as well as the devices that elicit them.

16.
Ann Rheum Dis ; 77(12): 1710-1719, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30269054

RESUMEN

OBJECTIVES: To evaluate the long-term efficacy and safety of canakinumab in patients with active systemic juvenile idiopathic arthritis (JIA). METHODS: Patients (2-19 years) entered two phase III studies and continued in the long-term extension (LTE) study. Efficacy assessments were performed every 3 months, including adapted JIA American College of Rheumatology (aJIA-ACR) criteria, Juvenile Arthritis Disease Activity Score (JADAS) and ACR clinical remission on medication criteria (CRACR). Efficacy analyses are reported as per the intent-to-treat population. RESULTS: 144 of the 177 patients (81%) enrolled in the core study entered the LTE. Overall, 75 patients (42%) completed and 102 (58%) discontinued mainly for inefficacy (63/102, 62%), with higher discontinuation rates noted in the late responders group (n=25/31, 81%) versus early responders (n=11/38, 29%). At 2 years, aJIA-ACR 50/70/90 response rates were 62%, 61% and 54%, respectively. CRACR was achieved by 20% of patients at month 6; 32% at 2 years. A JADAS low disease activity score was achieved by 49% of patients at 2 years. Efficacy results were maintained up to 5 years. Of the 128/177 (72.3%) patients on glucocorticoids, 20 (15.6%) discontinued and 28 (22%) tapered to 0.150 mg/kg/day. Seven patients discontinued canakinumab due to CR. There were 13 macrophage activation syndrome (three previously reported) and no additional deaths (three previously reported). No new safety findings were observed. CONCLUSION: Response to canakinumab treatment was sustained and associated with substantial glucocorticoid dose reduction or discontinuation and a relatively low retention-on-treatment rate. No new safety findings were observed on long-term use of canakinumab. TRIAL REGISTRATION NUMBERS: NCT00886769, NCT00889863, NCT00426218 and NCT00891046.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Antirreumáticos/uso terapéutico , Artritis Juvenil/tratamiento farmacológico , Adolescente , Anticuerpos Monoclonales Humanizados , Niño , Preescolar , Método Doble Ciego , Femenino , Humanos , Masculino , Resultado del Tratamiento , Adulto Joven
17.
Phys Rev Lett ; 120(7): 076801, 2018 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-29542936

RESUMEN

The widely reported magnetoresistance oscillations in LaAlO_{3}/SrTiO_{3} heterostructures have invariably been attributed to the Shubnikov-de Haas (SdH) effect, despite a pronounced inconsistency with low-field Hall resistance measurements. Here we report SdH-like resistance oscillations in quasi-1D electron waveguides created at the LaAlO_{3}/SrTiO_{3} interface by conductive atomic force microscopy lithography. These oscillations can be directly attributed to magnetic depopulation of magnetoelectric subbands. Our results suggest that the SdH oscillations in 2D SrTiO_{3}-based systems may originate from naturally forming quasi-1D channels.

18.
Phys Rev Lett ; 120(14): 147001, 2018 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-29694119

RESUMEN

We examine superconductivity in LaAlO_{3}/SrTiO_{3} channels with widths that transition from the 1D to the 2D regime. The superconducting critical current is independent of the channel width and increases approximately linearly with the number of parallel channels. Signatures of electron pairing outside of the superconducting regime are also found to be independent of the channel width. Collectively, these results indicate that superconductivity exists at the boundary of these channels and is absent within the interior region of the channels. The intrinsic 1D nature of superconductivity at the LaAlO_{3}/SrTiO_{3} interface imposes strong physical constraints on possible electron pairing mechanisms.

19.
BMC Med Educ ; 18(1): 166, 2018 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-30005595

RESUMEN

BACKGROUND: We report the development and evaluation of a web-based tool designed to facilitate student extra-curricular engagement in medical research through project matching students with academic supervisors. UK based university students were surveyed to explore their perceptions of undergraduate research, barriers and facilitators to current engagement. Following this, an online web-based intervention ( www.ProjectPal.org ) was developed to support access of students to research projects and supervisors. A pilot intervention was undertaken across a London-based university in January 2013 to February 2016. In March 2016, anonymised data were extracted from the prospective data log for analysis of website engagement and usage. Supervisors were surveyed to evaluate the website and student outputs. RESULTS: Fifty-one students responded to the electronic survey. Twenty-four (47%) reported frustration at a perceived lack of opportunities to carry out extra-curricular academic projects. Major barriers to engaging in undergraduate research reported were difficulties in identifying suitable supervisors (33/51; 65%) and time pressures (36/51; 71%) associated with this. Students reported being opportunistic in their engagement with undergraduate research. Following implementation of the website, 438 students signed up to ProjectPal and the website was accessed 1357 times. Access increased on a yearly basis. Overall, 70 projects were advertised by 35 supervisors. There were 86 applications made by students for these projects. By February 2016, the 70 projects had generated 5 peer-review publications with a further 7 manuscripts under peer-review, 14 national presentations, and 1 national prize. CONCLUSION: The use of an online platform to promote undergraduate engagement with extra-curricular research appears to facilitate extra-curricular engagement with research. Further work to understand the impact compared to normal opportunistic practices in enhancing student engagement is now underway.


Asunto(s)
Investigación Biomédica/estadística & datos numéricos , Educación de Pregrado en Medicina , Internet/estadística & datos numéricos , Mentores , Revisión de la Investigación por Pares , Estudiantes de Medicina/estadística & datos numéricos , Encuestas y Cuestionarios , Distinciones y Premios , Investigación Biomédica/organización & administración , Selección de Profesión , Femenino , Humanos , Londres , Masculino , Desarrollo de Programa , Estudios Prospectivos , Factores de Tiempo
20.
Kidney Int ; 92(3): 693-702, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28506760

RESUMEN

Co-presentation with both ANCA and anti-GBM antibodies is thought to be relatively rare. Current studies of such 'double-positive' cases report small numbers and variable outcomes. To study this further we retrospectively analyzed clinical features and long-term outcomes of a large cohort of 568 contemporary patients with ANCA-associated vasculitis, 41 patients with anti-GBM disease, and 37 double-positive patients with ANCA and anti-GBM disease from four European centers. Double-positive patients shared characteristics of ANCA-associated vasculitis (AAV), such as older age distribution and longer symptom duration before diagnosis, and features of anti-GBM disease, such as severe renal disease and high frequency of lung hemorrhage at presentation. Despite having more evidence of chronic injury on renal biopsy compared to patients with anti-GBM disease, double-positive patients had a greater tendency to recover from being dialysis-dependent after treatment and had intermediate long-term renal survival compared to the single-positive patients. However, overall patient survival was similar in all three groups. Predictors of poor patient survival included advanced age, severe renal failure, and lung hemorrhage at presentation. No single-positive anti-GBM patients experienced disease relapse, whereas approximately half of surviving patients with AAV and double-positive patients had recurrent disease during a median follow-up of 4.8 years. Thus, double-positive patients have a truly hybrid disease phenotype, requiring aggressive early treatment for anti-GBM disease, and careful long-term follow-up and consideration for maintenance immunosuppression for AAV. Since double-positivity appears common, further work is required to define the underlying mechanisms of this association and define optimum treatment strategies.


Asunto(s)
Enfermedad por Anticuerpos Antimembrana Basal Glomerular/inmunología , Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos/inmunología , Anticuerpos Anticitoplasma de Neutrófilos/sangre , Autoanticuerpos/sangre , Fallo Renal Crónico/inmunología , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Enfermedad por Anticuerpos Antimembrana Basal Glomerular/sangre , Enfermedad por Anticuerpos Antimembrana Basal Glomerular/mortalidad , Enfermedad por Anticuerpos Antimembrana Basal Glomerular/terapia , Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos/sangre , Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos/mortalidad , Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos/terapia , Niño , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Hemorragia/inmunología , Humanos , Inmunosupresores/uso terapéutico , Estimación de Kaplan-Meier , Riñón/inmunología , Riñón/patología , Fallo Renal Crónico/sangre , Fallo Renal Crónico/mortalidad , Fallo Renal Crónico/terapia , Enfermedades Pulmonares/inmunología , Masculino , Persona de Mediana Edad , Recurrencia , Diálisis Renal , Estudios Retrospectivos , Adulto Joven
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