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1.
Mol Genet Metab ; 142(1): 108349, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38458124

RESUMEN

Metachromatic leukodystrophy (MLD) is a devastating rare neurodegenerative disease. Typically, loss of motor and cognitive skills precedes early death. The disease is characterised by deficient lysosomal arylsulphatase A (ARSA) activity and an accumulation of undegraded sulphatide due to pathogenic variants in the ARSA gene. Atidarsagene autotemcel (arsa-cel), an ex vivo haematopoietic stem cell gene therapy was approved for use in the UK in 2021 to treat early-onset forms of pre- or early-symptomatic MLD. Optimal outcomes require early diagnosis, but in the absence of family history this is difficult to achieve without newborn screening (NBS). A pre-pilot MLD NBS study was conducted as a feasibility study in Manchester UK using a two-tiered screening test algorithm. Pre-established cutoff values (COV) for the first-tier C16:0 sulphatide (C16:0-S) and the second-tier ARSA tests were evaluated. Before the pre-pilot study, initial test validation using non­neonatal diagnostic bloodspots demonstrated ARSA pseudodeficiency status was associated with normal C16:0-S results for age (n = 43) and hence not expected to cause false positive results in this first-tier test. Instability of ARSA in bloodspot required transfer of NBS bloodspots from ambient temperature to -20°C storage within 7-8 days after heel prick, the earliest possible in this UK pre-pilot study. Eleven of 3687 de-identified NBS samples in the pre-pilot were positive for C16:0-S based on the pre-established COV of ≥170 nmol/l or ≥ 1.8 multiples of median (MoM). All 11 samples were subsequently tested negative determined by the ARSA COV of <20% mean of negative controls. However, two of 20 NBS samples from MLD patients would be missed by this C16:0-S COV. A further suspected false negative case that displayed 4% mean ARSA activity by single ARSA analysis for the initial test validation was confirmed by genotyping of this NBS bloodspot, a severe late infantile MLD phenotype was predicted. This led to urgent assessment of this child by authority approval and timely commencement of arsa-cel gene therapy at 11 months old. Secondary C16:0-S analysis of this NBS bloodspot was 150 nmol/l or 1.67 MoM. This was the lowest result reported thus far, a new COV of 1.65 MoM is recommended for future pilot studies. Furthermore, preliminary data of this study showed C16:1-OH sulphatide is more specific for MLD than C16:0-S. In conclusion, this pre-pilot study adds to the international evidence that recommends newborn screening for MLD, making it possible for patients to benefit fully from treatment through early diagnosis.


Asunto(s)
Cerebrósido Sulfatasa , Leucodistrofia Metacromática , Tamizaje Neonatal , Humanos , Leucodistrofia Metacromática/diagnóstico , Leucodistrofia Metacromática/terapia , Leucodistrofia Metacromática/genética , Tamizaje Neonatal/métodos , Recién Nacido , Proyectos Piloto , Cerebrósido Sulfatasa/genética , Femenino , Masculino , Sulfoglicoesfingolípidos , Lactante , Terapia Genética
2.
Glia ; 71(4): 1018-1035, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36537341

RESUMEN

The failure of remyelination in the human CNS contributes to axonal injury and disease progression in multiple sclerosis (MS). In contrast to regions of chronic demyelination in the human brain, remyelination in murine models is preceded by abundant oligodendrocyte progenitor cell (OPC) repopulation, such that OPC density within regions of demyelination far exceeds that of normal white matter (NWM). As such, we hypothesized that efficient OPC repopulation was a prerequisite of successful remyelination, and that increased lesion volume may contribute to the failure of OPC repopulation in human brain. In this study, we characterized the pattern of OPC activation and proliferation following induction of lysolecithin-induced chronic demyelination in adult rabbits. The density of OPCs never exceeded that of NWM and oligodendrocyte density did not recover even at 6 months post-injection. Rabbit OPC recruitment in large lesions was further characterized by chronic Sox2 expression in OPCs located in the lesion core and upregulation of quiescence-associated Prrx1 mRNA at the lesion border. Surprisingly, when small rabbit lesions of equivalent size to mouse were induced, they too exhibited reduced OPC repopulation. However, small lesions were distinct from large lesions as they displayed an almost complete lack of OPC proliferation following demyelination. These differences in the response to demyelination suggest that both volume dependent and species-specific mechanisms are critical in the regulation of OPC proliferation and lesion repopulation and suggest that alternate models will be necessary to fully understand the mechanisms that contribute to failed remyelination in MS.


Asunto(s)
Enfermedades Desmielinizantes , Esclerosis Múltiple , Células Precursoras de Oligodendrocitos , Animales , Conejos , Diferenciación Celular/fisiología , Enfermedades Desmielinizantes/patología , Proteínas de Homeodominio/metabolismo , Esclerosis Múltiple/patología , Vaina de Mielina/metabolismo , Vaina de Mielina/patología , Regeneración Nerviosa/fisiología , Células Precursoras de Oligodendrocitos/metabolismo , Oligodendroglía/metabolismo , Células Madre/metabolismo , Modelos Animales de Enfermedad
3.
Cell ; 134(5): 782-92, 2008 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-18775311

RESUMEN

Binding of the HIV envelope to the chemokine coreceptors triggers membrane fusion and signal transduction. The fusion process has been well characterized, yet the role of coreceptor signaling remains elusive. Here, we describe a critical function of the chemokine coreceptor signaling in facilitating HIV infection of resting CD4 T cells. We find that static cortical actin in resting T cells represents a restriction and that HIV utilizes the Galphai-dependent signaling from the chemokine coreceptor CXCR4 to activate a cellular actin-depolymerizing factor, cofilin, to overcome this restriction. HIV envelope-mediated cofilin activation and actin dynamics are important for a postentry process that leads to viral nuclear localization. Inhibition of HIV-mediated actin rearrangement markedly diminishes viral latent infection of resting T cells. Conversely, induction of active cofilin greatly facilitates it. These findings shed light on viral exploitation of cellular machinery in resting T cells, where chemokine receptor signaling becomes obligatory.


Asunto(s)
Actinas/metabolismo , Linfocitos T CD4-Positivos/virología , Cofilina 1/metabolismo , Proteína gp120 de Envoltorio del VIH/metabolismo , Receptores CXCR4/metabolismo , Secuencia de Aminoácidos , Antígenos CD4 , Células Cultivadas , Cofilina 1/química , VIH , Infecciones por VIH , Humanos , Datos de Secuencia Molecular , Transducción de Señal
4.
Pediatr Crit Care Med ; 23(1): e1-e9, 2022 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-34406168

RESUMEN

OBJECTIVES: To create a risk model for hospital-acquired venous thromboembolism in critically ill children upon admission to an ICU. DESIGN: Case-control study. SETTING: ICUs from eight children's hospitals throughout the United States. SUBJECTS: Critically ill children with hospital-acquired venous thromboembolism (cases) 0-21 years old and similar children without hospital-acquired venous thromboembolism (controls) from January 2012 to December 2016. Children with a recent cardiac surgery, asymptomatic venous thromboembolism, or a venous thromboembolism diagnosed before ICU admission were excluded. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The multi-institutional Children's Hospital-Acquired Thrombosis registry was used to identify cases and controls. Multivariable logistic regression was used to determine the association between hospital-acquired venous thromboembolism and putative risk factors present at or within 24 hours of ICU admission to develop the final model. A total of 548 hospital-acquired venous thromboembolism cases (median age, 0.8 yr; interquartile range, 0.1-10.2) and 187 controls (median age, 2.4 yr; interquartile range, 0.2-8.3) were analyzed. In the multivariable model, recent central venous catheter placement (odds ratio, 4.4; 95% CI, 2.7-7.1), immobility (odds ratio 3.6, 95% CI, 2.1-6.2), congenital heart disease (odds ratio 2.9, 95% CI, 1.7-4.7), length of hospital stay prior to ICU admission greater than or equal to 3 days (odds ratio, 2.5; 95% CI, 1.1-5.6), and history of autoimmune/inflammatory condition or current infection (odds ratio, 2.1; 95% CI, 1.2-3.4) were each independently associated with hospital-acquired venous thromboembolism. The risk model had an area under the receiver operating characteristic curve of 0.79 (95% CI, 0.73-0.84). CONCLUSIONS: Using the multicenter Children's Hospital-Acquired Thrombosis registry, we identified five independent risk factors for hospital-acquired venous thromboembolism in critically ill children, deriving a new hospital-acquired venous thromboembolism risk assessment model. A prospective validation study is underway to define a high-risk group for risk-stratified interventional trials investigating the efficacy and safety of prophylactic anticoagulation in critically ill children.


Asunto(s)
Trombosis , Tromboembolia Venosa , Adolescente , Adulto , Estudios de Casos y Controles , Niño , Preescolar , Enfermedad Crítica , Hospitales Pediátricos , Humanos , Lactante , Recién Nacido , Medición de Riesgo , Factores de Riesgo , Tromboembolia Venosa/epidemiología , Tromboembolia Venosa/etiología , Adulto Joven
5.
J Am Chem Soc ; 143(1): 163-175, 2021 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-33347315

RESUMEN

The solid-state properties of organic radicals depend on radical-radical interactions that are influenced by the superstructure of the crystalline phase. Here, we report the synthesis and characterization of a substituted tetracationic cyclophane, cyclobis(paraquat-p-1,4-dimethoxyphenylene), which associates in its bisradical dicationic redox state with the methyl viologen radical cation (MV•+) to give a 1:1 inclusion complex. The (super)structures of the reduced cyclophane and this 1:1 complex in the solid state deviate from the analogous (super)structures observed for the reduced state of cyclobis(paraquat-p-phenylene) and that of its trisradical tricationic complex. Titration experiments reveal that the methoxy substituents on the p-phenylene linkers do not influence binding of the cyclophane toward small neutral guests-such as dimethoxybenzene and tetrathiafulvalene-whereas binding of larger radical cationic guests such as MV•+ by the reduced cyclophane decreases 10-fold. X-ray diffraction analysis reveals that the solid-state superstructure of the 1:1 complex constitutes a discrete entity with weak intermolecular orbital overlap between neighboring complexes. Transient nutation EPR experiments and DFT calculations confirm that the complex has a doublet spin configuration in the ground state as a result of the strong orbital overlap, while the quartet-state spin configuration is higher in energy and inaccessible at ambient temperature. Superconducting quantum interference device (SQUID) measurements reveal that the trisradical tricationic complexes interact antiferromagnetically and form a one-dimensional Heisenberg antiferromagnetic chain along the a-axis of the crystal. These results offer insights into the design and synthesis of organic magnetic materials based on host-guest complexes.

6.
Am J Transplant ; 21(1): 322-328, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32888256

RESUMEN

Clinicians have few tools to predict the risk of alloimmune injury that would guide immunosuppression management in renal transplant patients. We evaluated human leukocyte antigen (HLA)-DR/DQ molecular mismatch to predict de novo donor-specific antibodies (DSAs) during the first year of transplant and explored how differences in tacrolimus exposure may modulate this risk. HLA-DR and -DQ eplet mismatches were determined between 444 donor-recipient pairs in Denver, Colorado between 2007 and 2013. Previously defined mismatch thresholds stratified recipients into low- (N = 119), intermediate- (N = 153), and high- (N = 172) risk categories. The area under the curve for DSA at 1 year was 0.84 and 0.82 for HLA-DR and HLA-DQ eplet mismatches, respectively. Compared to low-risk patients, there was a graded increase in risk of DR/DQ DSA in intermediate (HR 15.39, 95% CI 2.01-118.09, p = .009) and high-risk (HR 23.81, 95% CI 3.17-178.66, p = 0.002) categories. Intermediate- and high-risk patients with a mean tacrolimus <6 ng/ml versus >8 ng/ml had increased risk of DR/DQ DSA at 1 year (HR 2.34, 95% CI 1.05-5.22, p = .04). HLA molecular mismatch represents a reproducible, objective, and clinically relevant tool to stratify patients by alloimmune risk and may help guide personalized immunosuppression management.


Asunto(s)
Rechazo de Injerto , Tacrolimus , Rechazo de Injerto/etiología , Supervivencia de Injerto , Antígenos HLA/genética , Antígenos HLA-DR , Prueba de Histocompatibilidad , Humanos , Estados Unidos
7.
J Pediatr ; 228: 252-259.e1, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32920105

RESUMEN

OBJECTIVE: To identify pertinent clinical variables discernible on the day of hospital admission that can be used to assess risk for hospital-acquired venous thromboembolism (HA-VTE) in children. STUDY DESIGN: The Children's Hospital-Acquired Thrombosis Registry is a multi-institutional registry for all hospitalized participants aged 0-21 years diagnosed with a HA-VTE and non-VTE controls. A risk assessment model (RAM) for the development of HA-VTE using demographic and clinical VTE risk factors present at hospital admission was derived using weighted logistic regression and the least absolute shrinkage and selection (Lasso) procedure. The models were internally validated using 5-fold cross-validation. Discrimination and calibration were assessed using area under the receiver operating characteristic curve and Hosmer-Lemeshow goodness of fit, respectively. RESULTS: Clinical data from 728 cases with HA-VTE and 839 non-VTE controls, admitted between January 2012 and December 2016, were abstracted. Statistically significant RAM elements included age <1 year and 10-22 years, cancer, congenital heart disease, other high-risk conditions (inflammatory/autoimmune disease, blood-related disorder, protein-losing state, total parental nutrition dependence, thrombophilia/personal history of VTE), recent hospitalization, immobility, platelet count >350 K/µL, central venous catheter, recent surgery, steroids, and mechanical ventilation. The area under the receiver operating characteristic curve was 0.78 (95% CI 0.76-0.80). CONCLUSIONS: Once externally validated, this RAM will identify those who are at low-risk as well as the greatest-risk groups of hospitalized children for investigation of prophylactic strategies in future clinical trials.


Asunto(s)
Hospitalización/tendencias , Hospitales Pediátricos/estadística & datos numéricos , Sistema de Registros , Medición de Riesgo/métodos , Tromboembolia Venosa/epidemiología , Adolescente , Estudios de Casos y Controles , Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Lactante , Recién Nacido , Masculino , Curva ROC , Estudios Retrospectivos , Factores de Riesgo , Estados Unidos/epidemiología , Adulto Joven
8.
Blood ; 133(24): 2575-2585, 2019 06 13.
Artículo en Inglés | MEDLINE | ID: mdl-30992268

RESUMEN

Eltrombopag (EPAG) received approval from the US Food and Drug Administration for the treatment of refractory severe aplastic anemia (rSAA) based on treatment of 43 patients with doses escalating from 50 to 150 mg daily for 12 weeks. Response kinetics suggested that more prolonged administration of EPAG at a dose of 150 mg could speed and improve response rates. We enrolled 40 patients with rSAA in a study of EPAG 150 mg daily, with a primary end point of response at 24 weeks. Twenty (50%) of 40 patients responded at 24 weeks; 5 (25%) of 20 would have been deemed nonresponders at 12 weeks, the end point of the previous study. Fifteen of the 19 responding patients continuing on EPAG had drug discontinued for robust response; 5 of the 15 required EPAG re-initiation for relapse, with all recovering response. To analyze risk of clonal progression, we combined long-term data from the 83 patients with rSAA enrolled in both studies. Evolution to an abnormal karyotype occurred in 16 (19%), most within 6 months of EPAG initiation. Targeted deep sequencing/whole-exome sequencing was performed pre-EPAG and at primary response end point and/or time of clonal evolution or longest follow-up. Cytogenetic evolution did not correlate with mutational status, and overall mutated allele fractions of myeloid cancer genes did not increase on EPAG. In summary, extended administration of EPAG at a dose of 150 mg for 24 weeks rescued responses in some patients with rSAA not responding at 12 weeks. The temporal relationship between clonal evolution and drug exposure suggests that EPAG may promote expansion of dormant preexisting clones with an aberrant karyotype. The studies were registered at www.clinicaltrials.gov as #NCT00922883 and #NCT01891994.


Asunto(s)
Anemia Aplásica/tratamiento farmacológico , Benzoatos/administración & dosificación , Evolución Clonal/efectos de los fármacos , Hidrazinas/administración & dosificación , Pirazoles/administración & dosificación , Anemia Aplásica/genética , Femenino , Humanos , Masculino
9.
Eur J Haematol ; 107(3): 343-353, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34053123

RESUMEN

OBJECTIVES: This study aims to retrospectively assess C-lectin-like molecule 1 (CLL-1) bimodal expression on CD34+ blasts in acute myeloid leukemia (AML) patients (total N = 306) and explore potential CLL-1 bimodal associations with leukemia and patient-specific characteristics. METHODS: Flow cytometry assays were performed to assess the deeper immunophenotyping of CLL-1 bimodality. Cytogenetic analysis was performed to characterize the gene mutation on CLL-1-negative subpopulation of CLL-1 bimodal AML samples. RESULTS: The frequency of a bimodal pattern of CLL-1 expression of CD34+ blasts ranged from 8% to 65% in the different cohorts. Bimodal CLL-1 expression was most prevalent in patients with MDS-related AML (P = .011), ELN adverse risk (P = .002), NPM1 wild type (WT, P = .049), FLT3 WT (P = .035), and relatively low percentages of leukemia-associated immunophenotypes (P = .006). Additional immunophenotyping analysis revealed the CLL-1- subpopulation may consist of pre-B cells, immature myeloblasts, and hematopoietic stem cells. Furthermore, (pre)-leukemic mutations were detected in both CLL-1+ and CLL-1- subfractions of bimodal samples (N = 3). CONCLUSIONS: C-lectin-like molecule 1 bimodality occurs in about 25% of AML patients and the CLL-1- cell population still contains malignant cells, hence it may potentially limit the effectiveness of CLL-1-targeted therapies and warrant further investigation.


Asunto(s)
Biomarcadores de Tumor/genética , Células de la Médula Ósea/metabolismo , Lectinas Tipo C/genética , Leucemia Mieloide Aguda/genética , Mutación , Células Mieloides/metabolismo , Receptores Mitogénicos/genética , Antígenos CD34/genética , Antígenos CD34/inmunología , Biomarcadores de Tumor/inmunología , Células de la Médula Ósea/inmunología , Células de la Médula Ósea/patología , Análisis Citogenético , Femenino , Citometría de Flujo , Perfilación de la Expresión Génica , Regulación Leucémica de la Expresión Génica , Células Madre Hematopoyéticas/inmunología , Células Madre Hematopoyéticas/metabolismo , Células Madre Hematopoyéticas/patología , Humanos , Inmunofenotipificación , Lectinas Tipo C/inmunología , Leucemia Mieloide Aguda/inmunología , Leucemia Mieloide Aguda/patología , Masculino , Persona de Mediana Edad , Células Mieloides/inmunología , Células Mieloides/patología , Células Precursoras de Linfocitos B/inmunología , Células Precursoras de Linfocitos B/metabolismo , Células Precursoras de Linfocitos B/patología , Cultivo Primario de Células , Receptores Mitogénicos/inmunología
10.
BMC Neurol ; 21(1): 194, 2021 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-33980158

RESUMEN

BACKGROUND: The impact of nocturnal disturbance (ND) in Parkinson's disease on quality of life of patients in Western Countries is increasingly understood. Our study aimed to investigate ND prevalence and its quality of life impact in patients with advanced Parkinson's disease in China. METHODS: In a multicenter, tertiary-care hospital, outpatient-based, cross-sectional study, patients with advanced Parkinson's disease (Modified Hoehn & Yahr [H&Y] Stage II-IV with ≥3 h awake "off" time/day) from 10 tertiary hospitals throughout China completed the Parkinson's Disease Sleep Scale-2 (PDSS-2) and Parkinson's Disease Questionnaire-39 (PDQ-39). The primary endpoint was the percentage of patients with significant ND (PDSS-2 total score ≥ 15). Additional endpoints were demographic and clinical characteristics, PDSS-2 and PDQ-39 total and subscale scores, correlation between PDSS-2 and PDQ-39, and risk factors for ND and higher PDSS-2 or PDQ-39 scores. RESULTS: Of 448 patients analyzed (mean age 63.5 years, 47.3% female), 70.92% (95% confidence interval: 66.71, 75.13) had significant ND. Presence of ND and higher PDSS-2 scores were associated with longer disease duration and higher H&Y stage. Presence of ND was also associated with more awake "off" time/day and female sex. PDQ-39 scores were significantly worse for patients with ND versus those without ND; worse scores were associated with more awake "off" time/day, female sex, and higher H&Y stage. PDSS-2 and PDQ-39 total scores were associated: Pearson correlation coefficient 0.62 (p < 0.001). CONCLUSIONS: In China, ND was highly prevalent in patients with advanced Parkinson's disease and adversely impacted quality of life. This study highlights the importance of early diagnosis and optimized management of ND in patients with Parkinson's disease in China.


Asunto(s)
Enfermedad de Parkinson/complicaciones , Calidad de Vida , Trastornos del Sueño-Vigilia/epidemiología , Anciano , Pueblo Asiatico , China , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Sueño , Encuestas y Cuestionarios
11.
J Pediatr Hematol Oncol ; 43(5): 195-199, 2021 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-32815884

RESUMEN

There is little data specifically dedicated to the long-term outcomes of the hepatitis-associated variant of aplastic anemia (HAAA). A majority of patients with nonsevere (moderate) aplastic anemia progress to severe aplastic anemia, and severe aplastic anemia typically results in death if left untreated. We present 2 unique cases of HAAA that contribute to our knowledge of the natural history of this disease variant. One patient had moderate HAAA that never progressed to severe disease. The second patient had severe HAAA that spontaneously resolved without treatment. The rare possibility of moderate HAAA failing to progress to fulfill severe criteria, or of severe HAAA spontaneously improving, may complicate early treatment decisions for some patients.


Asunto(s)
Anemia Aplásica/etiología , Anemia Aplásica/terapia , Hepatitis/complicaciones , Adolescente , Anemia Aplásica/diagnóstico , Preescolar , Manejo de la Enfermedad , Progresión de la Enfermedad , Humanos , Masculino , Resultado del Tratamiento
12.
Br J Nurs ; 30(14): 852-856, 2021 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-34288745

RESUMEN

BACKGROUND: Historically, there has been limited research carried out on the competency of individuals undertaking advanced clinical roles. AIMS: To research advanced clinical practitioner (ACP) perceptions of the term competency, and how they evidence their competency in practice. METHODS: A cross-sectional, qualitative study used semi-structured interviews, which were analysed by content analysis. Six participants were recruited to the study. FINDINGS: There is disparity in the definitions of 'trainee' and 'qualified' ACP in clinical practice as well as disparity and ambiguity regarding being able to work in a supernumerary capacity during training and master's level study. There is a lack of agreement over the benchmark for qualified ACP status and the road to getting there. CONCLUSION: ACPs should be employed in a supernumerary capacity while training and work towards a full MSc in advanced clinical practice. They should maintain a portfolio of their competency. Work must also be carried out nationally to identify both generic and specialist curricula for ACPs to benchmark against.


Asunto(s)
Enfermería de Práctica Avanzada , Competencia Clínica , Enfermería de Práctica Avanzada/educación , Estudios Transversales , Humanos , Percepción
13.
Plant Mol Biol ; 102(6): 571-588, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31927659

RESUMEN

KEY MESSAGE: A family of repetitive proline-rich proteins interact with acidic pectins and play distinct roles in legume root cell walls affecting cortical and vascular structure. A proline-rich protein (PRP) family, composed of tandemly repeated Pro-Hyp-Val-X-Lys pentapeptide motifs, is found primarily in the Leguminosae. Four distinct size classes within this family are encoded by seven tightly linked genes: MtPRP1, MtPRP2 and MtPRP3, and four nearly identical MtPRP4 genes. Promoter fusions to ß-glucuronidase showed strong expression in the stele of hairy roots for all 4 PRP genes tested, with additional expression in the cortex for PRP1, PRP2 and PRP4. All except MtPRP4 are strongly expressed in non-tumorous roots, and secreted and ionically bound to root cell walls. These PRPs are absent from root epidermal cell walls, and PRP accumulation is highly localized within the walls of root cortical and vascular tissues. Within xylem tissue, PRPs are deposited in secondary thickenings where it is spatially exclusive to lignin. In newly differentiating xylem, PRPs are deposited in the regularly spaced paired-pits and pit membranes that hydraulically connect neighboring xylem elements. Hairpin-RNA knock-down constructs reducing PRP expression in Medicago truncatula hairy root tumors disrupted cortical and vascular patterning. Immunoblots showed that the knockdown tumors had potentially compensating increases in the non-targeted PRPs, all of which cross-react with the anti-PRP antibodies. However, PRP3 knockdown differed from knockdown of PRP1 and PRP2 in that it greatly reduced viability of hairy root tumors. We hypothesize that repetitive PRPs interact with acidic pectins to form block-copolymer gels that can play distinct roles in legume root cell walls.


Asunto(s)
Medicago truncatula/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raíces de Plantas/metabolismo , Dominios Proteicos Ricos en Prolina/genética , Pared Celular/metabolismo , Regulación de la Expresión Génica de las Plantas , Técnicas de Silenciamiento del Gen , Vectores Genéticos , Glucuronidasa , Medicago truncatula/genética , Raíces de Plantas/citología , Raíces de Plantas/genética , Plantas Modificadas Genéticamente , Regiones Promotoras Genéticas , Proteínas Salivales Ricas en Prolina , Xilema/metabolismo
14.
J Am Chem Soc ; 142(4): 2042-2050, 2020 01 29.
Artículo en Inglés | MEDLINE | ID: mdl-31935077

RESUMEN

A class of γ-cyclodextrin-containing hybrid frameworks (CD-HFs) has been synthesized, employing γ-cyclodextrin (γ-CD) as the primary building blocks, along with 4-methoxysalicylate (4-MS-) anions as the secondary building blocks. CD-HFs are constructed through the synergistic exploitation of coordinative, electrostatic, and dispersive forces. The syntheses have been carried out using an organic counteranion co-assembly strategy, which allows for the introduction of 4-MS-, in place of inorganic OH-, into the cationic γ-CD-containing metal-organic frameworks (CD-MOFs). Although the packing arrangement of the γ-CD tori in the solid-state superstructure of CD-HFs is identical to that of the previously reported CD-MOFs, CD-HFs crystallize with lower symmetry and in the cuboid space group P43212-when compared to CD-MOF-1, which has the cubic unit cell of I432 space group-on account of the chiral packing of the 4-MS- anions in the CD-HF superstructures. Importantly, CD-HFs have ultramicroporous apertures associated with the pore channels, a significant deviation from CD-MOF-1, as a consequence of the contribution from the 4-MS- anions, which serve as supramolecular baffles. In gas adsorption-desorption experiments, CD-HF-1 exhibits a Brunauer-Emmett-Teller (BET) surface area of 306 m2 g-1 for CO2 at 195 K, yet does not uptake N2 at 77 K, confirming the difference in porosity between CD-HF-1 and CD-MOF-1. Furthermore, the 4-MS- anions in CD-HF-1 can be exchanged with OH- anions, leading to an irreversible single-crystal to single-crystal transformation, with rearrangement of coordinated metal ions. Reversible transformations were also observed in CD-MOF-1 when OH- ions were exchanged for 4-MS- anions, with the space group changing from I432 to R32. This organic counteranion co-assembly strategy opens up new routes for the construction of hybrid frameworks, which are inaccessible by existing de novo MOF assembly methodologies.

15.
Epilepsy Behav ; 102: 106580, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31731109

RESUMEN

BACKGROUND: Retigabine is an antiepileptic drug developed for the adjunctive treatment of adults with epilepsy and partial-onset seizures (POS). Following its approval in 2011, reports of ophthalmological/dermatological pigmentation/discoloration led to a restriction of the indication in 2013, and in 2017, retigabine was voluntarily withdrawn from the market because of its limited usage. Here, data are reported from four open-label extension studies focusing on long-term safety with particular emphasis on ophthalmological and dermatological events. METHODS: Studies 113413 (NCT01336621), 114873 (NCT01777139), 115097 (NCT00310388), and 115098 (NCT00310375) were multicenter, open-label extension studies of retigabine (300-1200 mg/day) for the adjunctive treatment of adults with POS. Safety assessments included monitoring treatment-emergent adverse events (TEAEs) and serious adverse events (SAEs). When new safety issues were identified, protocols were amended to include additional on-treatment safety evaluations, including ophthalmological and dermatological examinations. Patients who had abnormal retinal pigmentation, unexplained vision change, pigmentation of nonretinal ocular tissue, or abnormal discoloration of skin, lips, nails, and/or mucosa at the end of the treatment phase were asked to enter a safety follow-up continuation phase comprising 6-monthly ophthalmological/dermatological assessments. RESULTS: The safety population (patients receiving ≥1 dose of retigabine in the open-label phase) comprised 98, 30, 376, and 181 patients for studies 113413, 114873, 115097, and 115098, respectively. Mean (standard deviation) treatment exposure ranged from 529 (424) to 1129 (999) days. In total, 68%-96% and 4%-27% of patients across the studies experienced TEAEs and TE SAEs, respectively. There were seven on-treatment deaths and two after discontinuation. Overall, 14%-73% of patients had an on-treatment eye examination, of whom 8/53, 4/22, 17/54, and 14/36 had abnormal retinal pigmentation and 15/53, 7/22, 15/54, and 11/36 had nonretinal ocular pigmentation in studies 113413, 114873, 115097, and 115098, respectively. Four patients had confirmed acquired vitelliform maculopathy. In patients with unresolved events at discontinuation and ≥1 posttreatment follow-up, retinal pigmentation resolved completely in 1/3, 0/3, 0/10, and 1/7 patients and nonretinal ocular pigmentation in 1/4, 0/3, 8/10, and 4/6 patients, respectively. Overall, 12%-83% of patients had an on-treatment dermatological examination, of whom 11/58, 0/25, 23/46, and 23/37 had any-tissue discoloration, respectively. In patients with unresolved events at discontinuation and ≥1 posttreatment follow-up, discoloration of skin, lips, nails, and/or mucosa resolved completely in 2/3, 0/0, 7/13, and 1/11 patients, respectively. CONCLUSIONS: The safety profile of retigabine in adults with POS across four open-label studies was generally consistent with data from previous placebo-controlled studies. Discoloration of various tissues occurred in a proportion of patients treated with retigabine and resolved completely in a small number of these patients following treatment discontinuation. In addition, comprehensive eye examination identified a new adverse reaction of acquired vitelliform maculopathy in a limited number of patients.


Asunto(s)
Anticonvulsivantes/efectos adversos , Carbamatos/efectos adversos , Oftalmopatías/inducido químicamente , Fenilendiaminas/efectos adversos , Convulsiones/tratamiento farmacológico , Enfermedades de la Piel/inducido químicamente , Adulto , Anticonvulsivantes/administración & dosificación , Carbamatos/administración & dosificación , Método Doble Ciego , Esquema de Medicación , Quimioterapia Combinada , Oftalmopatías/diagnóstico , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Fenilendiaminas/administración & dosificación , Convulsiones/diagnóstico , Enfermedades de la Piel/diagnóstico , Resultado del Tratamiento
16.
Phys Chem Chem Phys ; 22(16): 9117-9123, 2020 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-32301473

RESUMEN

Exposing a thiol-functionalised gold nanoparticle film chemiresistor to methanol in aqueous solution results in only a small electric current response as the thiol ligand/water partition coefficient of methanol is small, leading to only minor swelling of the chemiresistor film. Nevertheless, the current response to methanol can be enhanced if the chemiresistor becomes pre-exposed to a molecule with a large ligand/water partition coefficient P (e.g. octane with Po = 104.3). The large response enhancement is achieved because methanol, when added to an aqueous solution of octane, lowers the large initial partition coefficient of octane. Octane exiting the thiol ligands then leads to strong film shrinkage resulting in a relative current change much greater than the one otherwise induced by methanol alone. This was theoretically modelled for octane and heptane (Ph = 103.6). A strong response enhancement to methanol (>20 times) was observed experimentally by exposure to 2 ppm octane compared to direct testing of methanol in aqueous solution. Besides octane and heptane, molecules with P > 107 (e.g. permethrin) can theoretically be used to provide enhancement factors of several orders of magnitude. For practical reasons, heptane and octane saturate more quickly, thus enabling more rapid detection of methanol than higher P organic molecules.

17.
Clin Rehabil ; 34(12): 1458-1464, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32762340

RESUMEN

OBJECTIVE: To establish the feasibility of a randomized, placebo-controlled trial to investigate the effect of a specific immunotherapy bacterial lysate OM-89 (Uro-Vaxom®) in reducing the frequency of urinary tract infections in people with neurogenic bladder dysfunction. DESIGN: A parallel-group, double-blind, randomized, placebo-controlled trial. SETTING: Patients at home, recruited through out-patient contact, social media and patient support groups. SUBJECTS: People with a spinal cord injury, multiple sclerosis, transverse myelitis or cauda equina syndrome who had suffered three or more clinically diagnosed urinary tract infections treated with antibiotics over the preceding 12 months. INTERVENTIONS: All participants took one capsule of oral OM-89 immunotherapy (6 mg) or matching Placebo (randomisation ratio 1:1), once daily in the morning for 3 months. MAIN MEASURES: The primary outcome was occurrence of a symptomatic urinary tract infection treated with an antibiotic, assessed at 3 and 6 months. Feasibility measures included recruitment, retention and practical difficulties. RESULTS: Of 115 patients screened, 49 were recruited, one withdrew before randomization, and 23 were allocated to the control group receiving matching placebo. Six participants, all in the control group, discontinued the intervention; all participants provided full data at both follow-up times. Over 6 months, 18/25 active group patients had 55 infections, and 18/23 control group patients had 47 infections. Most research and clinical procedures were practical, and acceptable to participants. CONCLUSION: It is feasible to undertake a larger trial. We recommend broader inclusion criteria to increase eligibility and generalizability.


Asunto(s)
Adyuvantes Inmunológicos/uso terapéutico , Antiinfecciosos Urinarios/uso terapéutico , Antígenos Bacterianos , Vejiga Urinaria Neurogénica/complicaciones , Infecciones Urinarias/prevención & control , Síndrome de Cauda Equina , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Esclerosis Múltiple , Mielitis Transversa , Proyectos Piloto , Traumatismos de la Médula Espinal , Vejiga Urinaria Neurogénica/etiología
18.
J Biomech Eng ; 142(7)2020 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-31913457

RESUMEN

Advances in fabrication have allowed tissue engineers to better mimic complex structures and tissue interfaces by designing nanofibrous scaffolds with spatially graded material properties. However, the nonuniform properties that grant the desired biomechanical function also make these constructs difficult to characterize. In light of this, we developed a novel procedure to create graded nanofibrous scaffolds and determine the spatial distribution of their material properties. Multilayered nanofiber constructs were synthesized, controlling spatial gradation of the stiffness to mimic the soft tissue gradients found in tendon or ligament tissue. Constructs were characterized using uniaxial tension testing with digital image correlation (DIC) to measure the displacements throughout the sample, in a noncontacting fashion, as it deformed. Noise was removed from the displacement data using principal component analysis (PCA), and the final denoised field served as the input to an inverse elasticity problem whose solution determines the spatial distribution of the Young's modulus throughout the material, up to a multiplicative factor. Our approach was able to construct, characterize, and determine the spatially varying moduli, in four electrospun scaffolds, highlighting its great promise for analyzing tissues and engineered constructs with spatial gradations in modulus, such as those at the interfaces between two disparate tissues (e.g., myotendinous junction, tendon- and ligament-to-bone entheses).


Asunto(s)
Andamios del Tejido , Ligamentos , Nanofibras , Poliésteres , Tendones , Ingeniería de Tejidos
20.
J Am Chem Soc ; 141(31): 12296-12304, 2019 08 07.
Artículo en Inglés | MEDLINE | ID: mdl-31256588

RESUMEN

Prompted by a knowledge of the photoprotective mechanism operating in photosystem supercomplexes and bacterial antenna complexes by pigment binding proteins, we have appealed to a boxlike synthetic receptor (ExBox·4Cl) that binds a photosensitizer, 5,15-diphenylporphyrin (DPP), to provide photoprotection by regulating light energy. The hydrophilic ExBox4+ renders DPP soluble in water and modulates the phototoxicity of DPP by trapping it in its cavity and releasing it when required. While trapping removes access to the DPP triplet state, a pH-dependent release of diprotonated DPP (DPPH22+) restores the triplet deactivation pathway, thereby activating its ability to generate reactive oxygen species. We have employed the ExBox4+-bound DPP complex (ExBox4+⊃DPP) for the safe delivery of DPP into the lysosomes of cancer cells, imaging the cells by utilizing the fluorescence of the released DPPH22+ and regulating photodynamic therapy to kill cancer cells with high efficiency.


Asunto(s)
Lisosomas/metabolismo , Fotoquimioterapia , Fármacos Fotosensibilizantes/farmacología , Concentración de Iones de Hidrógeno , Interacciones Hidrofóbicas e Hidrofílicas , Modelos Moleculares , Conformación Molecular , Fármacos Fotosensibilizantes/química , Fármacos Fotosensibilizantes/metabolismo , Porfirinas/química , Porfirinas/metabolismo , Porfirinas/farmacología
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