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1.
Nucleic Acids Res ; 51(17): e92, 2023 09 22.
Artículo en Inglés | MEDLINE | ID: mdl-37602419

RESUMEN

Stochastic simulation models have played an important role in efforts to understand the mechanistic basis of prokaryotic transcription and translation. Despite the fundamental linkage of these processes in bacterial cells, however, most simulation models have been limited to representations of either transcription or translation. In addition, the available simulation models typically either attempt to recapitulate data from single-molecule experiments without considering cellular-scale high-throughput sequencing data or, conversely, seek to reproduce cellular-scale data without paying close attention to many of the mechanistic details. To address these limitations, we here present spotter (Simulation of Prokaryotic Operon Transcription & Translation Elongation Reactions), a flexible, user-friendly simulation model that offers highly-detailed combined representations of prokaryotic transcription, translation, and DNA supercoiling. In incorporating nascent transcript and ribosomal profiling sequencing data, spotter provides a critical bridge between data collected in single-molecule experiments and data collected at the cellular scale. Importantly, in addition to rapidly generating output that can be aggregated for comparison with next-generation sequencing and proteomics data, spotter produces residue-level positional information that can be used to visualize individual simulation trajectories in detail. We anticipate that spotter will be a useful tool in exploring the interplay of processes that are crucially linked in prokaryotes.


Asunto(s)
Nucleótidos , Biosíntesis de Proteínas , Simulación por Computador , Células Procariotas , Operón/genética
2.
J Am Chem Soc ; 146(38): 26139-26147, 2024 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-39252158

RESUMEN

Improved recycling technologies can offer sustainable end-of-life options for plastic waste. While polyolefins can be converted into small hydrocarbons over acid catalysts at high temperatures, we demonstrate an alternative mechano-catalytic strategy at ambient conditions. The mechanism is fundamentally different from classical acidity-driven high-temperature approaches, exploiting mechanochemically generated radical intermediates. Surface activation of zirconia grinding spheres creates redox active surface sites directly at the point of mechanical energy input. This allows control over mechano-radical reactivity, while powder catalysts are not active. Optimized milling parameters enable the formation of 45% C1-10 hydrocarbons from polypropylene within 1 h at ambient temperature. While mechanochemical bond scission is undesired in plastic production, we show that it can also be exploited for chemical recycling.

3.
Br J Nutr ; 131(7): 1189-1195, 2024 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-38012887

RESUMEN

Undernutrition is a major public health problem in developing countries. Around 40·2 % of children are stunted in Pakistan. This longitudinal study aimed to assess the effectiveness of locally produced ready-to-use supplementary foods in the prevention of stunting by detecting change in of children in intervention v. control arm against the 2006 WHO growth reference. A community-based non-randomised cluster-controlled trial was conducted from January 2018 to December 2020 in the district of Kurram, Khyber Pakhtunkhwa, Pakistan. A total of 80 clusters (each cluster comprising ≈ 250-300 households) were defined in the catchment population of twelve health facilities. Children aged 6-18 months were recruited n 1680. The intervention included a daily ration of 50 g - locally produced ready-to-use-supplementary food (Wawa-Mum). The main outcome of this study was a change in length for age z-score (LAZ) v. WHO growth standards. Comparison between the interventions was by t test and ANOVA. Cox proportional hazard models were used to assess the association between stunting occurrence and the utilisation of locally produced supplement. Out of the total 1680, fifty-one out of the total 1680, 51·1 out of the total 1680 and 51·1 % (n 859) were male. Mean age 13·9 months (sd + 859) were male. Mean age 13·9 months (sd + -4·4). At baseline, 36·9 % (n 618) were stunted. In the intervention group, mean LAZ score significantly increased from -1·13(2·2 sd) at baseline to -0·93(1·8 sd) at 6-month follow-up (P value 0·01) compared with the control group. The incidence rate of stunting in the intervention arm was 1·3 v. 3·4 per person year in the control arm. The control group had a significantly increased likelihood of stunting (Hazard Ratio (HR) 1·7, 95 % CI 1·46, 2·05, P value < 0·001) v. the intervention group. Locally produced ready-to-use supplementary food is an effective intervention for reducing stunting in children below 2 years of age. This can be provided as part of a malnutrition prevention package to overcome the alarming rates of stunting in Pakistan.


Asunto(s)
Desnutrición , Niño , Humanos , Masculino , Lactante , Preescolar , Femenino , Estudios Longitudinales , Pakistán/epidemiología , Desnutrición/epidemiología , Suplementos Dietéticos , Trastornos del Crecimiento/epidemiología , Trastornos del Crecimiento/prevención & control , Trastornos del Crecimiento/etiología
4.
Clin Exp Rheumatol ; 42(9): 1846-1855, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39051164

RESUMEN

Cutaneous inflammation is a common feature of several systemic autoimmune rheumatic diseases (SARDs) including systemic lupus erythematosus (SLE), undifferentiated connective tissue disease (UCTD), mixed connective tissue disease (MCTD) and dermatomyositis (DM) but is less common in other SARDs such as primary Sjögren's syndrome (pSS). It is important to understand whether the pathophysiological processes underlying skin inflammation are different or shared between SARDs to develop targeted therapies. This review will discuss commonalities and differences between inflammatory skin disease in SARDs focusing on histopathology and describe newer insights obtained from single-cell technologies.


Asunto(s)
Enfermedades Autoinmunes , Enfermedades Reumáticas , Análisis de la Célula Individual , Humanos , Enfermedades Reumáticas/inmunología , Enfermedades Autoinmunes/inmunología , Piel/patología , Piel/inmunología , Autoinmunidad , Dermatitis/inmunología , Dermatitis/etiología
5.
Conserv Biol ; 38(2): e14162, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37551767

RESUMEN

Trade in pangolins is illegal, and yet tons of their scales and products are seized at various ports. These large seizures are challenging to process and comprehensively genotype for upstream provenance tracing and species identification for prosecution. We implemented a scalable DNA barcoding pipeline in which rapid DNA extraction and MinION sequencing were used to genotype a substantial proportion of pangolin scales subsampled from 2 record shipments seized in Singapore in 2019 (37.5 t). We used reference sequences to match the scales to phylogeographical regions of origin. In total, we identified 2346 cytochrome b (cytb) barcodes of white-bellied (Phataginus tricuspis) (from 1091 scales), black-bellied (Phataginus tetradactyla) (227 scales), and giant (Smutsia gigantea) (1028 scales) pangolins. Haplotype diversity was higher for P. tricuspis scales (121 haplotypes, 66 novel) than that for P. tetradactyla (22 haplotypes, 15 novel) and S. gigantea (25 haplotypes, 21 novel) scales. Of the novel haplotypes, 74.2% were likely from western and west-central Africa, suggesting potential resurgence of poaching and newly exploited populations in these regions. Our results illustrate the utility of extensively subsampling large seizures and outline an efficient molecular approach for rapid genetic screening that should be accessible to most forensic laboratories and enforcement agencies.


Revelación de la magnitud de la caza furtiva del pangolín africano mediante el genotipo extenso de nanoporos de ADN de escamas incautadas Resumen Aunque el mercado de pangolines es ilegal, se incautan toneladas de sus escamas y productos derivados en varios puertos comerciales. Es un reto procesar estas magnas incautaciones y obtener el genotipo completo para usarlo en la trazabilidad logística ascendente e identificación de la especie y así imponer sanciones. Implementamos una canalización escalable del código de barras de ADN en el cual usamos la extracción rápida de ADN y la secuenciación MinION para obtener el genotipo de una proporción sustancial de las escamas de pangolín submuestreadas en dos cargamentos incautados en 2019 en Singapur (37.5 t). Usamos secuencias referenciales para emparejar las escamas con las regiones filogeográficas de origen. Identificamos en total 2,346 códigos de citocromo b (cytb) del pangolín de vientre blanco (Phataginus tricuspis) (de 1,091 escamas), de vientre negro (P. tetradactyla) (227 escamas) y del pangolín gigante (Smutsia gigantea) (1,028 escamas). La diversidad de haplotipos fue mayor en las escamas de P. tricuspis (121 haplotipos, 66 nuevos) que en las de P. tetradactyla (22 haplotipos, 15 nuevos) y S. gigantea (25 haplotipos, 21 nuevos). De los haplotipos nuevos, el 74.2% probablemente provenía del occidente y centro­occidente de África, lo que sugiere un resurgimiento potencial de la caza furtiva y poblaciones recién explotadas en estas regiones. Nuestros resultados demuestran la utilidad de submuestrear extensivamente las grandes incautaciones y esboza una estrategia molecular eficiente para un análisis genético rápido que debería ser accesible para la mayoría de los laboratorios forenses y las autoridades de aplicación.


Asunto(s)
Nanoporos , Pangolines , Humanos , Animales , Genotipo , Conservación de los Recursos Naturales/métodos , ADN , Convulsiones
6.
Cell ; 136(2): 261-71, 2009 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-19167328

RESUMEN

Recent advances have led to insights into the structure of the bacterial ribosome, but little is known about the 3D organization of ribosomes in the context of translating polysomes. We employed cryoelectron tomography and a template-matching approach to map 70S ribosomes in vitrified bacterial translation extracts and in lysates of active E. coli spheroplasts. In these preparations, polysomal arrangements were observed in which neighboring ribosomes are densely packed and exhibit preferred orientations. Analysis of characteristic examples of polysomes reveals a staggered or pseudohelical organization of ribosomes along the mRNA trace, with the transcript being sequestered on the inside, the tRNA entrance sites being accessible, and the polypeptide exit sites facing the cytosol. Modeling of elongating nascent polypeptide chains suggests that this arrangement maximizes the distance between nascent chains on adjacent ribosomes, thereby reducing the probability of intermolecular interactions that would give rise to aggregation and limit productive folding.


Asunto(s)
Escherichia coli/ultraestructura , Polirribosomas/ultraestructura , Microscopía por Crioelectrón , Tomografía con Microscopio Electrónico , Modelos Moleculares
7.
Am J Physiol Heart Circ Physiol ; 325(5): H1108-H1117, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37656132

RESUMEN

Sympathetic nerve activity (SNA) is tightly coupled with the respiratory cycle. In healthy human males, respiratory modulation of SNA does not change with age. However, it is unclear how this modulation is affected by age in females. We investigated whether respiratory sympathetic modulation is altered in healthy postmenopausal (PMF) versus premenopausal female (YF), and younger male (YM) adults, and determined its relationship to resting blood pressure. Muscle SNA (MSNA; microneurography), respiration (transducer belt), ECG, and continuous blood pressure were measured in 12 YF, 13 PMF, and 12 YM healthy volunteers. Respiratory modulation of MSNA was quantified during two phases of the respiratory cycle: mid-late expiration and inspiration/postinspiration. All groups showed respiratory modulation of MSNA (P < 0.0005). There was an interaction between the respiratory phase and group for MSNA [bursts/100 heartbeats (HB) (P = 0.004) and bursts/min (P = 0.029)], with smaller reductions in MSNA during inspiration observed in PMF versus the other groups. Respiratory modulation of blood pressure was also reduced in PMF versus YF (6 [2] vs. 12 [9] mmHg, P = 0.008) and YM (13 [13] mmHg, P = 0.001, median [interquartile range]). The magnitude of respiratory sympathetic modulation was related to resting blood pressure in PMF only, such that individuals with less modulation had greater resting blood pressure. The data indicate that aging in postmenopausal females is associated with less inspiratory inhibition of MSNA. This correlated with a higher resting blood pressure in PMF only. Thus, the reduced modulation of MSNA could contribute to the age-related rise in blood pressure that occurs in females.NEW & NOTEWORTHY The current study demonstrates that respiratory modulation of sympathetic nerve activity (SNA) is reduced in healthy postmenopausal (PMF) versus premenopausal females (YF). Furthermore, respiratory sympathetic modulation was negatively related to resting blood pressure in postmenopausal females, such that blood pressure was greater in individual with less modulation. Reduced respiratory sympathetic modulation may have implications for the autonomic control of blood pressure in aging postmenopausal females, by contributing to age-related sympathetic activation and reducing acute, respiratory-linked blood pressure variation.


Asunto(s)
Hipertensión , Hipotensión , Adulto , Femenino , Masculino , Humanos , Presión Sanguínea , Frecuencia Respiratoria , Respiración , Sistema Nervioso Autónomo , Envejecimiento
8.
Biochem Biophys Res Commun ; 642: 90-96, 2023 01 29.
Artículo en Inglés | MEDLINE | ID: mdl-36566567

RESUMEN

Calcific aortic valve disease affects the aortic side of the valve, exposed to low magnitude multidirectional ("disturbed) blood flow, more than it affects the ventricular side, exposed to high magnitude uniaxial flow. Overt disease is preceded by endothelial dysfunction and inflammation. Here we investigate the potential role of the transforming growth factor-ß (TGF-ß) receptor ALK5 in this process. Although ECs are always subject to shear stress due to blood flow, and their responses to shear stress are important in healthy valve development and homeostasis, low magnitude multidirectional flow can induce pathophysiological changes. Previous work has shown ALK5 to be an important mechanosensor. ALK5 transduces mechanically sensed signals via the activation of the SMAD2/3 transcriptional modulators. However, it is currently unclear precisely how ALK5-mediated shear stress responses translate into pathological changes under conditions of chronically disturbed flow. Here, we demonstrate that ALK5 mechanosensory signalling influences flow-induced endothelial leukocyte adhesion and paracellular permeability. Low magnitude multidirectional flow resulted in downregulation of the receptor, accompanied by increased SMAD2 phosphorylation, in human umbilical vein endothelial cell (HUVEC) monolayers. These changes correlated with elevated monocyte adhesion and significantly increased transendothelial transport of an albumin-sized tracer. These effects were abolished by inhibition of ALK5 kinase activity. Analysis of ALK5 expression patterns in porcine aortic valve tissue corroborated the findings from cell-based experiments. Together, these results suggest that ALK5 has a role in shear stress-associated cardiovascular disease pathology, emphasising the importance of further mechanistic investigations and supporting it as a potential therapeutic target.


Asunto(s)
Proteínas Serina-Treonina Quinasas , Receptores de Factores de Crecimiento Transformadores beta , Animales , Humanos , Fosforilación , Proteínas Serina-Treonina Quinasas/metabolismo , Receptor Tipo I de Factor de Crecimiento Transformador beta/metabolismo , Receptores de Factores de Crecimiento Transformadores beta/metabolismo , Transducción de Señal , Porcinos
9.
Diabetes Metab Res Rev ; 39(8): e3695, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37592876

RESUMEN

INTRODUCTION: The standardised mortality rate (SMR) for people with diabetes in England is 1.5-1.7, with differences in outcomes between sexes. There has been little work examining the factors that could have an impact on this or on what may determine sex differences in outcome. METHODS: Data were extracted for patients with type 2 diabetes (T2D) in Salford (England) in 2010 for the years up to 2020, including any deaths recorded. Expected deaths were calculated from annual Office of National Statistics mortality rate and life expectancy by age and gender, adjusted for the local Index of Multiple Deprivation (IMD). This provided the SMR deprivation (SMRd), and life expectancy years lost per death (LEYLD). The effects of treatment type, and clinical features on SMRd relative to sex were examined by univariable and multivariable analysis. RESULTS: Data from n = 11,806 (F = 5184; M = 6622) patients were included. Of these, n = 5540 were newly diagnosed and n = 3921 died (F = 1841; M = 2080). In total, n = 78,930 patient years. The expected deaths numbered n = 2596 (adjusted for age, sex, and IMD). Excess deaths were n = 1325 (F = 689; M = 636). Life expectancy years lost (LEYL) 18,989 (F = 9714; M = 9275). SMRd 1.51 (F = 1.60; M = 1.44) and LEYLD 4.84 years (F = 5.28; M = 4.46). The impact of risk factors was not different by sex. However, women had higher prevalence of % diagnosed >65 years of age; % last eGFR <60 mLs/min/1.73 m2 , and lower prevalence of % prescribed ACE-inhibitor/ARB, DPP4-inhibitor and SGLT2-inhibitor. Applying the male prevalence rate to the female population and expected mortality suggested n = 437 (55%) of excess T2D female deaths were attributed to sex difference in the prevalence of these risk and protective factors. CONCLUSIONS: Outcomes in women with T2DM are worse than in men, contributed to by greater prevalence of adverse factors and less prescribing of cardioprotective medication.


Asunto(s)
Enfermedades Cardiovasculares , Diabetes Mellitus Tipo 2 , Humanos , Femenino , Masculino , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Enfermedades Cardiovasculares/etiología , Factores de Riesgo , Antagonistas de Receptores de Angiotensina , Inhibidores de la Enzima Convertidora de Angiotensina , Factores de Riesgo de Enfermedad Cardiaca , Mortalidad
10.
Bipolar Disord ; 25(5): 402-409, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-36645255

RESUMEN

INTRODUCTION: Blood test monitoring is essential for the management of lithium treatment and National Institute for Health and Care Excellence guidance recommends 6-monthly serum testing of thyroid function. We examined conformity to these guidelines and the impact of monitoring outside these intervals. METHODS: We extracted serum lithium and thyroid hormone results at one centre between January 2009 and December 2020. We identified 266 patients who started lithium during this period with no history of thyroid abnormality within the previous 2 years and were at risk of developing thyroid abnormalities. We examined the interval between tests, time between onset of lithium testing and first thyroid-stimulating hormone (TSH) outside the laboratory reference range and assessed impact of testing outside recommended 6-monthly intervals. RESULTS: The most common testing frequency was 3 months (±1 month), accounting for 17.3% of test intervals. Kaplan-Meier analysis showed that most thyroid dysfunction manifests within 3 years (proportion with abnormal TSH at 3 years = 91.4%, 19.9% of total patients). In the first 3 months after commencing lithium therapy, eight patients developed subclinical hypothyroidism and had clinical follow-up data available. Of these, half spontaneously normalized without clinical intervention. In the remaining patients, thyroxine replacement was only initiated after multiple occasions of subclinical hypothyroidism (median = 2 years after initiating lithium, range: 6 months to 3 years). CONCLUSION: The peak interval at 3 months suggests that thyroid function is frequently checked at the same time as serum lithium, indicating too frequent testing. Our data support the recommended 6-monthly testing interval and highlight poor adherence to it.


Asunto(s)
Trastorno Bipolar , Hipotiroidismo , Enfermedades de la Tiroides , Humanos , Litio/uso terapéutico , Trastorno Bipolar/tratamiento farmacológico , Trastorno Bipolar/inducido químicamente , Hipotiroidismo/tratamiento farmacológico , Tirotropina
11.
Diabetes Obes Metab ; 25(12): 3662-3670, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37722968

RESUMEN

AIM: To quantify the impact of foot complications on mortality outcomes in people with type 2 diabetes (T2D), and how routinely measured factors might modulate that risk. MATERIALS AND METHODS: Data for individuals with T2D for 2010-2020, from the Salford Integrated Care Record (Salford, UK), were extracted for laboratory and clinical data, and deaths. Annual expected deaths were taken from Office of National Statistics mortality data. An index of multiple deprivation (IMD) adjusted the standardized mortality ratio (SMR_IMD). Life years lost per death (LYLD) was estimated from the difference between expected and actual deaths. RESULTS: A total of 11 806 T2D patients were included, with 5583 new diagnoses and 3921 deaths during 2010-2020. The number of expected deaths was 2135; after IMD adjustment, there were 2595 expected deaths. Therefore, excess deaths numbered 1326 (SMR_IMD 1.51). No foot complications were evident in n = 9857. This group had an SMR_IMD of 1.13 and 2.74 LYLD. In total, 2979 patients had any foot complication recorded. In this group, the SMD_IMR was 2.29; of these, 2555 (75%) had only one foot complication. Patients with a foot complication showed little difference in percentage HbA1c more than 58 mmol/mol. In multivariate analysis, for those with a foot complication and an albumin-to-creatinine ratio of more than 3 mg/mmol, the odds ratio (OR) for death was 1.93, and for an estimated glomerular filtration rate of less than 60 mL/min/1.73m2 , the OR for death was 1.92. CONCLUSIONS: Patients with T2D but without a foot complication have an SMR_IMD that is only slightly higher than that of the general population. Those diagnosed with a foot complication have a mortality risk that is double that of those without T2D.


Asunto(s)
Diabetes Mellitus Tipo 2 , Pie Diabético , Humanos , Diabetes Mellitus Tipo 2/complicaciones , Pie Diabético/complicaciones , Extremidad Inferior , Mortalidad
12.
Clin Transplant ; 37(1): e14849, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36343925

RESUMEN

BACKGROUND: Traditionally, simultaneous liver kidney transplantation (SLK) has been performed using a subcostal incision for the liver allograft and a lower abdominal incision for kidney transplantation (dual incision, DI). At our institution, we performed SLK using a single subcostal incision (SI). The aim of this study was to report the outcomes of single versus dual incisions for SLK. METHODS: A retrospective cohort study of consecutive SLK procedures performed at our center from January 2015 to April 2021 was performed. The demographic characteristics, complications, intraoperative findings, and complications after SI and DI were statistically compared. RESULTS: A total 37 SLK were performed (19 DI and 18 SI). The age and indications for transplantation were comparable between the two groups. Patient in SI group had significantly higher MELD score (27.0 ± 1.5 vs. 31.7 ± 1.5, p = .038). The cold ischemic time of kidney transplantation (599 ± 26 min vs. 447 ± 27 min, p < .001) and the total surgical time (508 ± 21 min vs. 423 ± 22 min, p = .008) were significantly shorter in the SI group. The incidence of complications and post-transplant kidney function was comparable between the groups. A slightly higher incidence of surgical site complications was noted in the DI group without any statistically significance (p = .178). CONCLUSIONS: Single-subcostal incision SLK is technically feasible and has comparable outcomes to dual-incision SLK. SI was associated with shorter cold ischemic time for kidney transplant, as well as shorter overall operative time.


Asunto(s)
Trasplante de Riñón , Humanos , Trasplante de Riñón/efectos adversos , Trasplante de Riñón/métodos , Estudios Retrospectivos , Estudios de Factibilidad , Resultado del Tratamiento , Riñón , Hígado
13.
Clin Transplant ; 37(12): e15141, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37755152

RESUMEN

BACKGROUND: Post-COVID-19 cholangiopathy is an emerging cholestatic liver disease observed in patients recovering from severe COVID-19 infection. Its prognosis is poor, necessitating liver transplantation in some cases. This study aimed to investigate the outcomes of liver transplantation for post-COVID-19 cholangiopathy. METHODS: Seven patients who underwent liver transplantation for post-COVID-19 cholangiopathy at three institutions between 2020 and 2022 were included in this retrospective multi-center case series. RESULTS: At the time of initial COVID-19 infection, all patients developed acute respiratory distress syndrome, and six patients (86%) required ICU admission. Median time intervals from the initial COVID-19 diagnosis to the diagnosis of post-COVID-19 cholangiopathy and liver transplantation were 4 and 12 months, respectively. Four patients underwent living donor liver transplantation, and three patients underwent deceased donor liver transplantation. The median MELD score was 22 (range, 10-38). No significant intraoperative complications were observed. The median ICU and hospital stays were 2.5 and 12.5 days, respectively. One patient died due to respiratory failure 5 months after liver transplantation. Currently, the patient and graft survival rate is 86% at a median follow-up of 11 months. CONCLUSIONS: Liver transplantation is a viable option for patients with post-COVID-19 cholangiopathy with acceptable outcome. Timely identification of this disease and appropriate management, including evaluation for liver transplantation, are essential.


Asunto(s)
COVID-19 , Trasplante de Hígado , Humanos , Prueba de COVID-19 , Donadores Vivos , Estudios Retrospectivos
14.
Proc Natl Acad Sci U S A ; 117(6): 3114-3122, 2020 02 11.
Artículo en Inglés | MEDLINE | ID: mdl-31988134

RESUMEN

Plasmodium falciparum vaccine RTS,S/AS01 is based on the major NPNA repeat and the C-terminal region of the circumsporozoite protein (CSP). RTS,S-induced NPNA-specific antibody titer and avidity have been associated with high-level protection in naïve subjects, but efficacy and longevity in target populations is relatively low. In an effort to improve upon RTS,S, a minimal repeat-only, epitope-focused, protective, malaria vaccine was designed. Repeat antigen copy number and flexibility was optimized using the tobacco mosaic virus (TMV) display platform. Comparing antigenicity of TMV displaying 3 to 20 copies of NPNA revealed that low copy number can reduce the abundance of low-affinity monoclonal antibody (mAb) epitopes while retaining high-affinity mAb epitopes. TMV presentation improved titer and avidity of repeat-specific Abs compared to a nearly full-length protein vaccine (FL-CSP). NPNAx5 antigen displayed as a loop on the TMV particle was found to be most optimal and its efficacy could be further augmented by combination with a human-use adjuvant ALFQ that contains immune-stimulators. These data were confirmed in rhesus macaques where a low dose of TMV-NPNAx5 elicited Abs that persisted at functional levels for up to 11 mo. We show here a complex association between NPNA copy number, flexibility, antigenicity, immunogenicity, and efficacy of CSP-based vaccines. We hypothesize that designing minimal epitope CSP vaccines could confer better and more durable protection against malaria. Preclinical data presented here supports the evaluation of TMV-NPNAx5/ALFQ in human trials.


Asunto(s)
Anticuerpos Antiprotozoarios/inmunología , Vacunas contra la Malaria , Malaria Falciparum/inmunología , Plasmodium falciparum , Proteínas Protozoarias , Virus del Mosaico del Tabaco/genética , Animales , Células HEK293 , Humanos , Inmunogenicidad Vacunal , Macaca mulatta , Vacunas contra la Malaria/química , Vacunas contra la Malaria/genética , Vacunas contra la Malaria/inmunología , Ratones , Ratones Endogámicos C57BL , Modelos Moleculares , Plasmodium falciparum/genética , Plasmodium falciparum/inmunología , Ingeniería de Proteínas , Proteínas Protozoarias/química , Proteínas Protozoarias/genética , Proteínas Protozoarias/inmunología , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/inmunología
15.
Int J Mol Sci ; 24(24)2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-38139335

RESUMEN

We investigated the impact of synthetic nucleic acid antigens on the autoantibody profiles in patients with localized scleroderma, an autoimmune skin disease. Anti-DNA antibodies, including double-stranded DNA (dsDNA) and single-stranded DNA (ssDNA), are common among autoimmune diseases, such as systemic lupus erythematosus and localized scleroderma. Based on recent studies, we hypothesized that the sequence of nucleic acid antigens has an impact on the autoimmune reactions in localized scleroderma. To test our hypothesis, we synthesized a panel of DNA and RNA antigens and used them for autoantibody profiling of 70 children with localized scleroderma compared with the healthy controls and patients with pediatric systemic lupus erythematosus (as a disease control). Among the tested antigens, dsD4, which contains the sequence of the human oncogene BRAF, showed a particularly strong presence in localized scleroderma but not systemic lupus erythematosus. Disease activity in patients was significantly associated with dsD4 autoantibody levels. We confirmed this result in vivo by using a bleomycin-induced mouse model of localized scleroderma. When administered intraperitoneally, dsD4 promoted an active polyclonal response in the mouse model. Our study highlights sequence specificity for nucleic acid antigens in localized scleroderma that could potentially lead to developing novel early-stage diagnostic tools.


Asunto(s)
Enfermedades Autoinmunes , Lupus Eritematoso Sistémico , Esclerodermia Localizada , Animales , Ratones , Humanos , Niño , Autoanticuerpos/genética , Antígenos , ADN , ADN de Cadena Simple
16.
Int J Mol Sci ; 24(23)2023 11 30.
Artículo en Inglés | MEDLINE | ID: mdl-38069302

RESUMEN

Bariatric surgery improves dyslipidaemia and reduces body weight, but it remains unclear how bariatric surgery modulates gene expression in fat cells to influence the proprotein convertase subtilisin/kexin type 9 (PCSK-9) and low-density lipoprotein receptor (LDLR) gene expression. The expression of the PCSK9/LDLR/tumor necrosis factor-alpha (TNFα) gene in adipose tissue was measured in two groups of Zucker Diabetic Sprague Dawley (ZDSD) rats after Roux-en-Y gastric bypass (RYGB) surgery or 'SHAM' operation. There was lower PCSK9 (p = 0.02) and higher LDLR gene expression (p = 0.02) in adipose tissue in rats after RYGB. Weight change did not correlate with PCSK9 gene expression (r = -0.5, p = 0.08) or TNFα gene expression (r = -0.4, p = 0.1). TNFα gene expression was positively correlated with PCSK9 gene expression (r = 0.7, p = 0.001) but not correlated with LDLR expression (r = -0.3, p = 0.3). Circulating triglyceride levels were lower in RYGB compared to the SHAM group (1.1 (0.8-1.4) vs. 1.5 (1.0-4.2), p = 0.038) mmol/L with no difference in cholesterol levels. LDLR gene expression was increased post-bariatric surgery with the potential to reduce the number of circulating LDL particles. PCSK9 gene expression and TNFα gene expression were positively correlated after RYGB in ZDSD rats, suggesting that the modulation of pro-inflammatory pathways in adipose tissue after RYGB may partly relate to PCSK9 and LDLR gene expression.


Asunto(s)
Cirugía Bariátrica , Diabetes Mellitus Experimental , Animales , Ratas , Tejido Adiposo/metabolismo , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/cirugía , Expresión Génica , Inflamación/genética , Obesidad/genética , Obesidad/cirugía , Proproteína Convertasa 9/genética , Proproteína Convertasas/genética , Ratas Sprague-Dawley , Ratas Zucker , Receptores de LDL/genética , Receptores de LDL/metabolismo , Serina Endopeptidasas/metabolismo , Subtilisina/genética , Factor de Necrosis Tumoral alfa/genética
17.
Foot Ankle Surg ; 29(3): 218-222, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36646595

RESUMEN

BACKGROUND: Forefoot ulceration in diabetes requires significant resources, with high cost and low rates of success. The authors present the results of tendon procedures (percutaneous toe tenotomy and percutaneous tendo-achilles lengthening) under local anaesthetic to adjust mechanics in patients with diabetic neuropathic forefoot ulceration. METHODS: Retrospective review of electronic patient record of 19 patients (22 feet) undergoing local anaesthetic tendon procedures between April 2019 and April 2021 with a 12 month follow up period. Size of ulcer, rate of ulcer healing, complication rates and ulcer recurrence were recorded and compared to a population of conservatively-managed patients (14 patients, 15 feet) treated prior to the introduction of tendon procedures. All clinical information obtained from electronic patient records. RESULTS: All patients undergoing tendon procedures achieved complete ulcer healing at a mean time of 3.3 weeks for toe tip ulcers (after toe tenotomy) and 4.5 weeks for metatarsal head ulcers (after Achilles lengthening). There were no admissions for diabetic foot sepsis, reduced recurrence, reduced amputation rates and no mortality. Of the conservatively managed cohort, only 3 of the 15 achieved ulcer resolution without recurrence within the 12 month study period. The cohort managed conservatively had an average cost of £ 9902 per patient, per annum. The intervention cost was £ 1211 per patient, saving an average of £ 8691 per patient, per annum with ulcer resolution (88 % reduction in costs). CONCLUSION: Significant patient benefit, reduction in resource use and cost saving was seen with this simple intervention, which merits full evaluation in a clinical trial. LEVEL OF EVIDENCE: Level-IV.


Asunto(s)
Tendón Calcáneo , Pie Diabético , Úlcera del Pie , Ortopedia , Humanos , Tendón Calcáneo/cirugía , Anestésicos Locales , Úlcera del Pie/etiología , Tenotomía/métodos , Úlcera/etiología , Estudios Retrospectivos
18.
Sex Transm Infect ; 98(5): 376-379, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-34479989

RESUMEN

INTRODUCTION: Globally, gay and bisexual men (GBM) are over-represented in HIV, syphilis and gonorrhoea cases. However, surveillance systems rarely provide meaningful measures of inequity, such as population-specific rates, due to a lack of sexual orientation denominators. HIV, gonorrhoea and syphilis are legally notifiable diseases in New Zealand (NZ); we calculate rates by sexual orientation for the first time. METHODS: We analysed 2019 national surveillance data on HIV, syphilis and gonorrhoea notifications disaggregated by sexual orientation. Unique health records identified duplicate notifications and reinfections. Missing data were imputed from known cases. We used the NZ Health Survey 2014/2015 to estimate population sizes by sexual orientation, measured in two ways (current sexual identity, sexual contact in the previous 12 months with men, women or both). We calculated notification rates per 100 000 for each sexual orientation subgroup and rate ratios. RESULTS: In 2019, GBM accounted for 76.3%, 65.7% and 39.4% of HIV, syphilis and gonorrhoea notifications, respectively. Population rates per 100 000 for HIV were 158.3 (gay/bisexual men) and 0.5 (heterosexuals); for syphilis, population rates per 100 000 were 1231.1 (gay/bisexual men), 5.0 (lesbian/bisexual women) and 7.6 (heterosexuals); for gonorrhoea (imputed), population rates per 100 000 were 6843.2 (gay/bisexual men), 225.1 (lesbian/bisexual women) and 120.9 (heterosexuals). The rate ratios for GBM compared with heterosexuals were: 348.3 (HIV); 162.7 (syphilis); and 56.6 (gonorrhoea). Inequities remained in sensitivity analysis (substituting sexual identity with sexual behaviour in the previous 12 months). CONCLUSION: GBM in NZ experience profound inequities in HIV, syphilis and gonorrhoea. Rate ratios by sexual orientation provide useful 'at-a-glance' measures of inequity in disease incidence.


Asunto(s)
Gonorrea , Infecciones por VIH , Minorías Sexuales y de Género , Sífilis , Femenino , Gonorrea/diagnóstico , Gonorrea/epidemiología , Infecciones por VIH/diagnóstico , Infecciones por VIH/epidemiología , Humanos , Masculino , Nueva Zelanda/epidemiología , Conducta Sexual , Sífilis/diagnóstico , Sífilis/epidemiología
19.
Diabet Med ; 39(4): e14774, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34936128

RESUMEN

AIMS: Evidence suggests that some people with type 1 diabetes mellitus (T1DM) experience temporary instability of blood glucose (BG) levels after COVID-19 vaccination. We aimed to assess this objectively. METHODS: We examined the interstitial glucose profile of 97 consecutive adults (age ≥ 18 years) with T1DM using the FreeStyle Libre® flash glucose monitor in the periods immediately before and after their first COVID-19 vaccination. The primary outcome measure was percentage (%) interstitial glucose readings within the target range 3.9-10 mmol/L for 7 days prior to the vaccination and the 7 days after the vaccination. Data are mean ± standard error. RESULTS: There was a significant decrease in the % interstitial glucose on target (3.9-10.0) for the 7 days following vaccination (mean 52.2% ± 2.0%) versus pre-COVID-19 vaccination (mean 55.0% ± 2.0%) (p = 0.030). 58% of individuals with T1DM showed a reduction in the 'time in target range' in the week after vaccination. 30% showed a decrease of time within the target range of over 10%, and 10% showed a decrease in time within target range of over 20%. The change in interstitial glucose proportion on target in the week following vaccination was most pronounced for people taking metformin/dapagliflozin + basal bolus insulin (change -7.6%) and for people with HbA1c below the median (change -5.7%). CONCLUSION: In T1DM, we have shown that initial COVID-19 vaccination can cause temporary perturbation of interstitial glucose, with this effect more pronounced in people talking oral hypoglycaemic medication plus insulin, and when HbA1c is lower.


Asunto(s)
Vacunas contra la COVID-19/uso terapéutico , COVID-19/prevención & control , Diabetes Mellitus Tipo 1/sangre , Control Glucémico , Vacunación , Adolescente , Adulto , Anciano , Glucemia/análisis , Glucemia/metabolismo , Automonitorización de la Glucosa Sanguínea , COVID-19/epidemiología , Estudios de Cohortes , Diabetes Mellitus Tipo 1/epidemiología , Diabetes Mellitus Tipo 1/terapia , Femenino , Hemoglobina Glucada/análisis , Hemoglobina Glucada/metabolismo , Control Glucémico/métodos , Control Glucémico/estadística & datos numéricos , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento , Reino Unido/epidemiología , Vacunación/métodos , Vacunación/estadística & datos numéricos , Adulto Joven
20.
Biomacromolecules ; 23(3): 743-759, 2022 03 14.
Artículo en Inglés | MEDLINE | ID: mdl-34994549

RESUMEN

Amphipathic copolymers such as poly(styrene-maleic acid) (SMA) are promising tools for the facile extraction of membrane proteins (MPs) into native nanodiscs. Here, we designed and synthesized a library of well-defined alternating copolymers of SMA analogues in order to elucidate polymer properties that are important for MP solubilization and stability. MP extraction efficiency was determined using KcsA from E. coli membranes, and general solubilization efficiency was investigated via turbidimetry experiments on membranes of E. coli, yeast mitochondria, and synthetic lipids. Remarkably, halogenation of SMA copolymers dramatically improved solubilization efficiency in all systems, while substituents on the copolymer backbone improved resistance to Ca2+. Relevant polymer properties were found to include hydrophobic balance, size and positioning of substituents, rigidity, and electronic effects. The library thus contributes to the rational design of copolymers for the study of MPs.


Asunto(s)
Proteínas de la Membrana , Poliestirenos , Escherichia coli , Interacciones Hidrofóbicas e Hidrofílicas , Maleatos/química , Proteínas de la Membrana/química , Polímeros , Poliestirenos/química
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