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1.
Opt Express ; 31(7): 11354-11362, 2023 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-37155773

RESUMEN

Second-harmonic generation (SHG) is a second-order nonlinear optical process that is not allowed in media with inversion symmetry. However, due to the broken symmetry at the surface, surface SHG still occurs, but is generally weak. We experimentally investigate the surface SHG in periodic stacks of alternating, subwavelength dielectric layers, which have a large number of surfaces, thus enhancing surface SHG considerably. To this end, multilayer stacks of SiO2/TiO2 were grown by Plasma Enhanced Atomic Layer Deposition (PEALD) on fused silica substrates. With this technique, individual layers of a thickness of less than 2 nm can be fabricated. We experimentally show that under large angles of incidence (> 20 degrees) there is substantial SHG, well beyond the level, which can be observed from simple interfaces. We perform this experiment for samples with different periods and thicknesses of SiO2/TiO2 and our results are in agreement with theoretical calculations.

2.
Pancreatology ; 23(5): 481-490, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37321941

RESUMEN

Chymotrypsin C (CTRC) is a digestive serine protease produced by the pancreas that regulates intrapancreatic trypsin activity and provides a defensive mechanism against chronic pancreatitis (CP). CTRC exerts its protective effect by promoting degradation of trypsinogen, the precursor to trypsin. Loss-of-function missense and microdeletion variants of CTRC are found in around 4% of CP cases and increase disease risk by approximately 3-7-fold. In addition, a commonly occurring synonymous CTRC variant c.180C>T (p.Gly60=) was reported to increase CP risk in various cohorts but a global analysis of its impact has been lacking. Here, we analyzed the frequency and effect size of variant c.180C>T in Hungarian and pan-European cohorts, and performed meta-analysis of the new and published genetic association data. When allele frequency was considered, meta-analysis revealed an overall frequency of 14.2% in patients and 8.7% in controls (allelic odds ratio (OR) 2.18, 95% confidence interval (CI) 1.72-2.75). When genotypes were examined, c.180TT homozygosity was observed in 3.9% of CP patients and in 1.2% of controls, and c.180CT heterozygosity was present in 22.9% of CP patients and in 15.5% of controls. Relative to the c.180CC genotype, the genotypic OR values were 5.29 (95% CI 2.63-10.64), and 1.94 (95% CI 1.57-2.38), respectively, indicating stronger CP risk in homozygous carriers. Finally, we obtained preliminary evidence that the variant is associated with reduced CTRC mRNA levels in the pancreas. Taken together, the results indicate that CTRC variant c.180C>T is a clinically relevant risk factor, and should be considered when genetic etiology of CP is investigated.


Asunto(s)
Pancreatitis Crónica , Humanos , Tripsina/genética , Pancreatitis Crónica/genética , Quimotripsina/genética , Quimotripsina/metabolismo , Estudios de Casos y Controles , Predisposición Genética a la Enfermedad , Mutación
3.
Opt Express ; 30(22): 40884-40896, 2022 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-36299013

RESUMEN

Second harmonic generation is enhanced at the surface lattice resonance in plasmonic nanoparticle arrays. We carried out a parametric investigation on two-dimensional lattices composed of gold nanobars where the centrosymmetry is broken at oblique incidence. We study the influence of the periodicity, the incidence angle and the direction of the linear input polarization on the second harmonic generation. Excitation of the surface lattice resonance either at the fundamental or second harmonic wavelength, achieved by varying the incidence angle, enhance the conversion efficiency. As a special case, we demonstrate that both the wavelengths can be simultaneously in resonance for a specific period of the lattice. In this double resonant case, maximum second harmonic power is achieved.

4.
Opt Lett ; 47(22): 6025-6028, 2022 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37219163

RESUMEN

We investigate experimentally third harmonic generation (THG) from plasmonic metasurfaces consisting of two-dimensional rectangular lattices of centrosymmetric gold nanobars. By varying the incidence angle and the lattice period, we show how surface lattice resonances (SLRs) at the involved wavelengths are the major contributors in determining the magnitude of the nonlinear effects. A further boost on THG is observed when we excite together more than one SLR, either at the same or at different frequency. When such multiple resonances take place, interesting phenomena are observed, such as maximum THG enhancement for counter-propagating surface waves along the metasurface, and cascading effect emulating a third-order nonlinearity.

5.
J Microsc ; 284(1): 56-73, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34214188

RESUMEN

A modern day light microscope has evolved from a tool devoted to making primarily empirical observations to what is now a sophisticated , quantitative device that is an integral part of both physical and life science research. Nowadays, microscopes are found in nearly every experimental laboratory. However, despite their prevalent use in capturing and quantifying scientific phenomena, neither a thorough understanding of the principles underlying quantitative imaging techniques nor appropriate knowledge of how to calibrate, operate and maintain microscopes can be taken for granted. This is clearly demonstrated by the well-documented and widespread difficulties that are routinely encountered in evaluating acquired data and reproducing scientific experiments. Indeed, studies have shown that more than 70% of researchers have tried and failed to repeat another scientist's experiments, while more than half have even failed to reproduce their own experiments. One factor behind the reproducibility crisis of experiments published in scientific journals is the frequent underreporting of imaging methods caused by a lack of awareness and/or a lack of knowledge of the applied technique. Whereas quality control procedures for some methods used in biomedical research, such as genomics (e.g. DNA sequencing, RNA-seq) or cytometry, have been introduced (e.g. ENCODE), this issue has not been tackled for optical microscopy instrumentation and images. Although many calibration standards and protocols have been published, there is a lack of awareness and agreement on common standards and guidelines for quality assessment and reproducibility. In April 2020, the QUality Assessment and REProducibility for instruments and images in Light Microscopy (QUAREP-LiMi) initiative was formed. This initiative comprises imaging scientists from academia and industry who share a common interest in achieving a better understanding of the performance and limitations of microscopes and improved quality control (QC) in light microscopy. The ultimate goal of the QUAREP-LiMi initiative is to establish a set of common QC standards, guidelines, metadata models and tools, including detailed protocols, with the ultimate aim of improving reproducible advances in scientific research. This White Paper (1) summarizes the major obstacles identified in the field that motivated the launch of the QUAREP-LiMi initiative; (2) identifies the urgent need to address these obstacles in a grassroots manner, through a community of stakeholders including, researchers, imaging scientists, bioimage analysts, bioimage informatics developers, corporate partners, funding agencies, standards organizations, scientific publishers and observers of such; (3) outlines the current actions of the QUAREP-LiMi initiative and (4) proposes future steps that can be taken to improve the dissemination and acceptance of the proposed guidelines to manage QC. To summarize, the principal goal of the QUAREP-LiMi initiative is to improve the overall quality and reproducibility of light microscope image data by introducing broadly accepted standard practices and accurately captured image data metrics.


Asunto(s)
Microscopía , Estándares de Referencia , Reproducibilidad de los Resultados
6.
Pancreatology ; 20(7): 1511-1518, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32952041

RESUMEN

BACKGROUND/OBJECTIVES: Pancreatic ductal adenocarcinoma (PDAC) is frequently associated with severe pain. Given the almost inevitably fatal nature of the disease, pain control is crucial. However, data on quality of pain management in PDAC is scarce. METHODS: This is a multi-center, prospective study to evaluate the quality of pain management in PDAC. Insufficient pain treatment (undertreatment) was prevalent if there was an incongruence between the patients level of pain and the potency of analgesic drug therapy. Determinants of pain and undertreatment were identified using multivariable logistic regression. RESULTS: 139 patients with histologically confirmed PDAC were analyzed. The prevalence of pain was 63%, with approximately one third of the patients grading their pain as moderate to severe. Palliative stage (OR: 3.37, 95%CI: 1.23-9.21, p = 0.018) and localization of the primary tumor in the body or tail (OR: 2.57, 95%CI: 1.05-6.31, p = 0.039) were independent determinants of pain. Of those reporting pain, 60% were undertreated and in 89% pain interfered with activities and emotions. Age ≥ 70 years (OR: 3.20, 95%CI: 1.09-9.41, p = 0.035) was an independent predictor of undertreatment. Patients with longer-known PDAC ( ≥ 30 days) showed improved pain management compared to new cases (OR: 0.19, 95%CI: 0.05-0.81, p = 0.025). Treatment by gastroenterologists (OR: 0.22, 95%CI: 0.05-0.89, p = 0.034) was associated with less undertreatment. CONCLUSIONS: The results show a high proportion of PDAC patients with pain, pain interference and undertreatment, whose characteristics could help to identify patients at risk in the future. Several changes in the management of cancer-related pain are necessary to overcome barriers to optimal treatment.


Asunto(s)
Dolor en Cáncer/terapia , Carcinoma Ductal Pancreático/complicaciones , Manejo del Dolor/métodos , Neoplasias Pancreáticas/complicaciones , Factores de Edad , Anciano , Analgésicos/administración & dosificación , Analgésicos/uso terapéutico , Dolor en Cáncer/tratamiento farmacológico , Dolor en Cáncer/epidemiología , Carcinoma Ductal Pancreático/terapia , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Dolor/tratamiento farmacológico , Dimensión del Dolor , Cuidados Paliativos , Páncreas/patología , Neoplasias Pancreáticas/terapia , Prevalencia , Estudios Prospectivos , Factores Socioeconómicos , Resultado del Tratamiento
7.
Pancreatology ; 20(8): 1598-1603, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33036922

RESUMEN

BACKGROUND: /Objectives: A recent Genome-wide Association Study (GWAS) in alcoholic chronic pancreatitis (ACP) identified a novel association with the CTRB1-CTRB2 (chymotrypsinogen B1, B2) locus, linked to a 16.6 kb inversion that was confirmed in non-alcoholic chronic pancreatitis (NACP). Moreover, recent findings on the function of CTRB1 and CTRB2 suggest a protective role in pancreatitis development. The aim of the present study was to investigate the CTRB1-CTRB2 locus for rare genetic variants associated with chronic pancreatitis (CP). METHODS: We analyzed 134 patients with ACP and 203 patients with NACP and compared them to up to 258 healthy controls. Genotyping was performed with polymerase chain reaction, followed by Sanger sequencing of all exons and the exon-intron-boundaries of CTRB1 and CTRB2. Finally, in silico analyses of the identified variants were conducted. RESULTS: None of the seven rare missense variants or the single 5'-UTR variant in CTRB1 and CTRB2 was associated with ACP or NACP. In silico analysis predicted that variant p. Trp5Leu in CTRB1 and variant c.-4C > T in CTRB2 might alter protein expression and variants p. Asp222His in CTRB1 and p. Ala247Thr in CTRB2 might affect protein function. However, all of these variants were also described in public databases. CONCLUSIONS: The present study did not reveal an association of rare variants in CTRB1 and CTRB2 with ACP or NACP. Although rare missense variants were almost exclusively found in patients, only four variants were predicted to affect protein expression or function. Thus, a major influence of rare variants in the CTRB1-CTRB2 locus on CP development is unlikely.


Asunto(s)
Quimotripsina , Estudio de Asociación del Genoma Completo , Pancreatitis Crónica , Quimotripsina/genética , Humanos , Pancreatitis Crónica/genética , Análisis de Secuencia de ADN
8.
Pancreatology ; 20(2): 187-192, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31870801

RESUMEN

BACKGROUND: /Objectives: AGE and their receptors like RAGE and Galectin-3 can activate inflammatory pathways and have been associated with chronic inflammatory diseases. Several studies investigated the role of AGE, Galectin-3 and sRAGE in pancreatic diseases, whereas no comprehensive data for chronic pancreatitis (CP) are available. METHODS: Serum samples from CP patients without an active inflammatory process (85 ACP; 26 NACP patients) and 40 healthy controls were collected. Levels of AGE, sRAGE and Galectin-3 were measured by ELISA. To exclude potential influences of previously described RAGE SNPs on detected serum levels, we analyzed variants rs207128, rs207060, rs1800625, and rs1800624 by melting curve technique in 378 CP patients and 338 controls. RESULTS: AGE and Galectin-3 serum levels were significantly elevated in both ACP and NACP patients compared to controls (AGE: 56.61 ± 3.043 vs. 31.71 ± 2.308 ng/mL; p < 0.001; Galectin-3: 16.63 ± 0.6297 vs. 10.81 ± 0.4835 ng/mL; p < 0.001). In contrast, mean serum sRAGE levels were significantly reduced in CP patients compared to controls (sRAGE: 829.7 ± 37.10 vs. 1135 ± 55.74 ng/mL; p < 0.001). All results were consistent after correction for gender, age and diabetes mellitus. No genetic association with CP was found. CONCLUSIONS: Our extensive analysis demonstrated the importance of aging related pathways in the pathogenesis of CP. As the results were consistent in ACP and NACP, both entities most likely share common pathomechanisms. Most probably the involved pathways are a general hallmark of an inflammatory state in CP that is even present in symptom-free intervals.


Asunto(s)
Antígenos de Neoplasias/sangre , Galectinas/sangre , Productos Finales de Glicación Avanzada/sangre , Proteínas Quinasas Activadas por Mitógenos/sangre , Pancreatitis Crónica/sangre , Adulto , Anciano , Anciano de 80 o más Años , Envejecimiento , Alcoholismo/complicaciones , Antígenos de Neoplasias/genética , Proteínas Sanguíneas/genética , Complicaciones de la Diabetes/sangre , Femenino , Galectinas/genética , Productos Finales de Glicación Avanzada/genética , Humanos , Inflamación/sangre , Masculino , Persona de Mediana Edad , Proteínas Quinasas Activadas por Mitógenos/genética , Pancreatitis Crónica/complicaciones , Pancreatitis Crónica/genética , Polimorfismo de Nucleótido Simple , Adulto Joven
9.
Endoscopy ; 51(7): 684-688, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30986867

RESUMEN

BACKGROUND: Endoscopic full-thickness transoral outlet reduction (efTOR) is a therapeutic option to reduce a dilated gastrojejunal anastomosis (GJA) after Roux-en-Y gastric bypass (RYGB). Mucosal ablation with argon plasma coagulation (APC) is usually performed to achieve tissue adaptation. However, rupture of sutures before scarring can lead to recurrent dilatation of the GJA. Here, we describe efTOR with a semicircumferential endoscopic submucosal dissection (ESD-efTOR) as an alternative to APC-efTOR. METHODS: We enrolled 41 patients with comparable baseline characteristics (APC-efTOR 26; ESD-efTOR 15). The main objectives were reduction in the GJA diameter and in ruptured sutures. Technical success, complications, total weight loss (TWL), and percentage of total and excess weight loss (%TWL and %EWL) at 3 and 12 months, were assessed. RESULTS: ESD-efTOR resulted in significantly fewer ruptured sutures (20 % vs. 69 %; P = 0.004) and a greater reduction in the GJA (major 20 % vs. 0 %; minor 54 % vs. 37 %; no reduction 13 % vs. 58 %; P = 0.02) after 3 months. Technical efficacy, examination time, and rate of complications were comparable. CONCLUSIONS: ESD-efTOR resulted in a significantly greater reduction in the GJA diameter and a lower risk of ruptured sutures compared with APC-efTOR.


Asunto(s)
Coagulación con Plasma de Argón/métodos , Resección Endoscópica de la Mucosa/métodos , Unión Esofagogástrica/cirugía , Derivación Gástrica/efectos adversos , Yeyuno/cirugía , Cirugía Endoscópica por Orificios Naturales/métodos , Estómago/cirugía , Anastomosis Quirúrgica/efectos adversos , Constricción Patológica/diagnóstico , Constricción Patológica/etiología , Constricción Patológica/cirugía , Unión Esofagogástrica/diagnóstico por imagen , Estudios de Seguimiento , Boca , Obesidad Mórbida/cirugía , Reoperación/métodos , Técnicas de Sutura/efectos adversos , Factores de Tiempo
10.
Gut ; 67(10): 1855-1863, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-28754779

RESUMEN

OBJECTIVE: Alcohol-related pancreatitis is associated with a disproportionately large number of hospitalisations among GI disorders. Despite its clinical importance, genetic susceptibility to alcoholic chronic pancreatitis (CP) is poorly characterised. To identify risk genes for alcoholic CP and to evaluate their relevance in non-alcoholic CP, we performed a genome-wide association study and functional characterisation of a new pancreatitis locus. DESIGN: 1959 European alcoholic CP patients and population-based controls from the KORA, LIFE and INCIPE studies (n=4708) as well as chronic alcoholics from the GESGA consortium (n=1332) were screened with Illumina technology. For replication, three European cohorts comprising 1650 patients with non-alcoholic CP and 6695 controls originating from the same countries were used. RESULTS: We replicated previously reported risk loci CLDN2-MORC4, CTRC, PRSS1-PRSS2 and SPINK1 in alcoholic CP patients. We identified CTRB1-CTRB2 (chymotrypsin B1 and B2) as a new risk locus with lead single-nucleotide polymorphism (SNP) rs8055167 (OR 1.35, 95% CI 1.23 to 1.6). We found that a 16.6 kb inversion in the CTRB1-CTRB2 locus was in linkage disequilibrium with the CP-associated SNPs and was best tagged by rs8048956. The association was replicated in three independent European non-alcoholic CP cohorts of 1650 patients and 6695 controls (OR 1.62, 95% CI 1.42 to 1.86). The inversion changes the expression ratio of the CTRB1 and CTRB2 isoforms and thereby affects protective trypsinogen degradation and ultimately pancreatitis risk. CONCLUSION: An inversion in the CTRB1-CTRB2 locus modifies risk for alcoholic and non-alcoholic CP indicating that common pathomechanisms are involved in these inflammatory disorders.


Asunto(s)
Quimotripsina/genética , Pancreatitis Alcohólica , Adulto , Anciano , Europa (Continente)/epidemiología , Femenino , Predisposición Genética a la Enfermedad , Humanos , Masculino , Persona de Mediana Edad , Pancreatitis Alcohólica/epidemiología , Pancreatitis Alcohólica/genética , Polimorfismo de Nucleótido Simple
11.
Pancreatology ; 18(5): 477-481, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29884332

RESUMEN

BACKGROUND/OBJECTIVES: Acute pancreatitis (AP) is one of the most common gastrointestinal disorders often requiring hospitalization. Frequent aetiologies are gallstones and alcohol abuse. In contrast to chronic pancreatitis (CP) few robust genetic associations have been described. Here we analysed whether common variants in the CLDN2-MORC4 and the PRSS1-PRSS2 locus that increase recurrent AP and CP risk associate with AP. METHODS: We screened 1462 AP patients and 3999 controls with melting curve analysis for SNPs rs10273639 (PRSS1-PRSS2), rs7057398 (RIPPLY), and rs12688220 (MORC4). Calculations were performed for the overall group, aetiology, and gender sub-groups. To examine genotype-phenotype relationships we performed several meta-analyses. RESULTS: Meta-analyses of all AP patients depicted significant (p-value < 0.05) associations for rs10273639 (odds ratio (OR) 0.88, 95% confidence interval (CI) 0.81-0.97, p-value 0.01), rs7057398 (OR 1.27, 95% CI 1.07-1.5, p-value 0.005), and rs12688220 (OR 1.32, 95% CI 1.12-1.56, p-value 0.001). For the different aetiology groups a significant association was shown for rs10273639 (OR 0.76, 95% CI 0.63-0.92, p-value 0.005), rs7057398 (OR 1.43, 95% CI 1.07-1.92, p-value 0.02), and rs12688220 (OR 1.44, 95% CI 1.07-1.93, p-value 0.02) in the alcoholic sub-group only. CONCLUSIONS: The association of CP risk variants with different AP aetiologies, which is strongest in the alcoholic AP group, might implicate common pathomechanisms most likely between alcoholic AP and CP.

12.
Pancreatology ; 16(5): 708-14, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27554641

RESUMEN

BACKGROUND: Chronic pancreatitis is an inflammatory disorder of the pancreas that is associated with accelerated mortality for patients suffering from this disease. The association between chronic inflammation and accelerated biological ageing has been well described and is often referred to as "inflammageing". In this review we seek to determine how systemic inflammation in chronic pancreatitis may contribute to an accelerated ageing phenotype. METHODS: A systematic literature search with a predefined search protocol was performed on Medline, Embase and Cochrane libraries according to the PRISMA guidelines. RESULTS: The initial search identified 499 studies. After title, abstract and full text screen of the search results, 20 were included for further evaluation. In the 20 remaining articles 41 inflammatory mediators were identified - mainly involved in chronic inflammation, fibrosis and particularly cardinal features of inflammageing such as sarcopenia and osteoporosis. CONCLUSION: Chronic pancreatitis is associated with elevated levels of inflammatory mediators many of which are associated with an accelerated ageing phenotype and may explain some of the clinical sequelae of this disease.


Asunto(s)
Biomarcadores/sangre , Inflamación/sangre , Inflamación/diagnóstico por imagen , Pancreatitis Crónica/sangre , Pancreatitis Crónica/diagnóstico por imagen , Humanos , Inflamación/etiología , Fenotipo
13.
Hum Mutat ; 36(3): 350-6, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25546417

RESUMEN

Mutations of the human cationic trypsinogen gene (PRSS1) are frequently found in association with hereditary pancreatitis. The most frequent variants p.N29I and p.R122H are recognized as disease-causing mutations. Three pseudogene paralogs in the human trypsinogen family, including trypsinogen 6 (PRSS3P2), carry sequence variations in exon 3 that mimic the p.R122H mutation. In routine genetic testing of patients with chronic pancreatitis, we identified in two unrelated individuals similar gene conversion events of 24-71 nucleotides length between exon 3 of the PRSS1 (acceptor) and PRSS3P2 (donor) genes. The converted allele resulted in three nonsynonymous alterations c.343T>A (p.S115T), c.347G>C (p.R116P), and c.365_366delinsAT (p.R122H). Functional analysis of the conversion triple mutant revealed markedly increased autoactivation resulting in high and sustained trypsin activity in the presence of chymotrypsin C. This activation phenotype was identical to that of the p.R122H mutant. In addition, cellular secretion of the triple mutant from transfected HEK 293T cells was increased about twofold and this effect was attributable to mutation p.R116P. Our observations confirm and extend the notion that recombination events between members of the trypsinogen family can generate high-risk PRSS1 alleles. The pathogenic phenotype of the novel conversion is explained by a unique combination of increased trypsinogen activation and secretion.


Asunto(s)
Conversión Génica , Pancreatitis Crónica/genética , Seudogenes , Tripsina/genética , Alelos , Línea Celular , Niño , Femenino , Humanos , Masculino , Adulto Joven
14.
Gut ; 63(2): 337-43, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23455445

RESUMEN

OBJECTIVE: Hereditary pancreatitis is caused by mutations in human cationic trypsinogen (PRSS1) which lead to increased autoactivation by altering chymotrypsin C (CTRC)-dependent trypsinogen activation and degradation. Exceptions are some cysteine mutations which cause misfolding, intracellular retention and endoplasmic reticulum stress. Clinical relevance of many PRSS1 variants found in patients with sporadic chronic pancreatitis is unknown but often assumed by analogy with known disease-causing mutations. Functional comparison of PRSS1 variants found in sporadic and hereditary cases is needed to resolve this dilemma. DESIGN: Here, we investigated the functional phenotype of 13 published PRSS1 variants with respect to autoactivation in the presence of CTRC and cellular secretion. RESULTS: Only mutation p.D100H increased trypsinogen autoactivation, but this gain in function was offset by a marked reduction in secretion. Five mutants (p.P36R, p.G83E, p.I88N, p.V123M, p.S124F) showed decreased autoactivation due to increased degradation by CTRC. Five mutants exhibited strongly (p.D100H, p.C139F) or moderately (p.K92N, p.S124F, p.G208A) reduced secretion, whereas mutant p.K170E showed slightly increased secretion. Mutant p.I88N was also secreted to higher levels but was rapidly degraded by CTRC. Finally, three mutants (p.Q98K, p.T137M, p.S181G) had no phenotypic alterations relative to wild-type trypsinogen. CONCLUSIONS: Rare PRSS1 variants found in sporadic chronic pancreatitis do not stimulate autoactivation but may cause increased degradation, impaired secretion or no functional change. Variants with reduced secretion are likely pathogenic due to mutation-induced misfolding and consequent endoplasmic reticulum stress.


Asunto(s)
Quimotripsina/metabolismo , Páncreas/patología , Pancreatitis Crónica/genética , Tripsina/genética , Western Blotting , Técnicas de Cultivo de Célula , Electroforesis en Gel de Poliacrilamida , Predisposición Genética a la Enfermedad , Variación Genética , Humanos , Mutación , Pancreatitis Crónica/metabolismo , Fenotipo , Tripsina/metabolismo
15.
Gut ; 62(11): 1616-24, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22942235

RESUMEN

OBJECTIVE: The digestive enzyme chymotrypsin C (CTRC) protects against pancreatitis by promoting degradation of trypsinogen, thereby curtailing potentially harmful trypsinogen activation. Loss-of-function variants in CTRC increase the risk for chronic pancreatitis. The aim of the present study was to perform comprehensive functional analysis of all missense CTRC variants identified to date. DESIGN: We investigated secretion, activity and degradation of 27 published and five novel CTRC mutants. We also assessed the effect of five mutants on endoplasmic reticulum (ER) stress. RESULTS: None of the mutants exhibited a gain of function, such as increased secretion or activity. By contrast, 11 mutants showed marked loss of function, three mutants had moderate functional defects, whereas 18 mutants were functionally similar to wild-type CTRC. The functional deficiencies observed were diminished secretion, impaired catalytic activity and degradation by trypsin. Mutants with a secretion defect caused ER stress that was proportional to the loss in secretion. ER stress was not associated with loss-of-function phenotypes related to catalytic defect or proteolytic instability. CONCLUSIONS: Pathogenic CTRC variants cause loss of function by three distinct but mutually non-exclusive mechanisms that affect secretion, activity and proteolytic stability. ER stress may be induced by a subset of CTRC mutants, but does not represent a common pathological mechanism of CTRC variants. This phenotypic dataset should aid in the classification of the clinical relevance of CTRC variants identified in patients with chronic pancreatitis.


Asunto(s)
Quimotripsina/genética , Mutación Missense , Pancreatitis Crónica/genética , Biocatálisis , Quimotripsina/efectos de los fármacos , Quimotripsina/metabolismo , Quimotripsina/fisiología , Medios de Cultivo Condicionados , Estrés del Retículo Endoplásmico/genética , Predisposición Genética a la Enfermedad , Variación Genética , Células HEK293 , Humanos , Pancreatitis Crónica/enzimología , Tripsina/farmacología
17.
PLoS One ; 18(9): e0286882, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37768969

RESUMEN

INTRODUCTION: Fatty liver diseases (FLD), especially defined as metabolic dysfunction-associated FLD (MAFLD), is of growing importance for patients and health-care providers. Extrahepatic comorbidities, predominantly coronary artery disease (CAD), contribute to excess morbidity and mortality in FLD. Although the association of FLD and CAD is well known, underlying pathophysiological links are not fully understood. Non-invasive means of liver diagnostic enable a fast and thorough characterization of FLD. We therefore assessed the severity of FLD in a cohort of patients at risk of CAD. METHODS: Patients scheduled for coronary angiography were characterized by anthropometry, serum-based indices of liver fibrosis (NFS, FIB4), abdominal ultrasound and vibration controlled transient elastography (VCTE) including controlled attenuation parameter (CAP) and the Fibroscan-AST (FAST) score. Patients were stratified according to indication of therapeutic coronary intervention. RESULTS: 120 patients were recruited, MAFLD was found in 41%, while advanced fibrosis or cirrhosis were present in only 5%. Coronary vascular intervention was indicated in 42% (n = 50). Severity of steatosis assessed by CAP and risk of fibrosis defined by elevated liver stiffness (VCTE>8 kPa) and fibrosis indices were associated with the need for coronary intervention. FAST score, a marker of fibrotic steatohepatitis, was elevated in the intervention group (0.22 vs. 0.12, p<0.001). Multivariate regression analysis revealed FAST score as strongest predictor of CAD (OR 2.3 95%, CI 1.40-2.96). DISCUSSION: MAFLD is a frequent comorbidity in patients at CAD risk, but advanced liver disease has a low prevalence in patients undergoing elective coronary angiography. Therefore, a routine VCTE-based screening for FLD cannot be recommended in cardiac patients. The association of indicators of steatohepatitis with advanced CAD points to inflammatory processes as a conjoint mechanism of both diseases.


Asunto(s)
Enfermedad de la Arteria Coronaria , Diagnóstico por Imagen de Elasticidad , Enfermedad del Hígado Graso no Alcohólico , Humanos , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/complicaciones , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Enfermedad del Hígado Graso no Alcohólico/epidemiología , Enfermedad del Hígado Graso no Alcohólico/diagnóstico , Cirrosis Hepática/complicaciones , Cirrosis Hepática/diagnóstico , Fibrosis , Prevalencia
18.
Sci Rep ; 12(1): 8286, 2022 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-35585160

RESUMEN

Classical light sources emit a randomly-timed stream of individual photons, the spatial distribution of which can be detected with a camera to form an image. Quantum light sources, based on parametric down conversion, emit photons as correlated photon-pairs. The spatial correlations between the photons enables imaging systems where the preferential selection of photon-pairs allows for enhancements in the noise performance over what is possible using classical light sources. However, until now the technical challenge of measuring, and correlating both photons has led to system complexity. Here we show that a camera capable of resolving the number of individual photons in each pixel of the detector array can be used to record an image formed from these photon-pair events and hence achieve a greater contrast than possible using a classical light source. We achieve an enhancement in the ratio of two-photon events compared to one-photon events using spatially correlated SPDC light compared to uncorrelated illumination by a LED. These results indicate the potential advantages of using photon counting cameras in quantum imaging schemes and these advantages will further increase as the technology is developed. Operating in photon sparse regimes such systems have potential applications in low-light microscopy and covert imaging.

19.
Obes Surg ; 32(8): 2495-2503, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35713854

RESUMEN

PURPOSE: People with obesity often develop non-alcoholic fatty liver disease (NAFLD) and are at high risk of progression to non-alcoholic steatohepatitis (NASH). Few therapies are effective other than bariatric surgery. We therefore analyzed data from duodenal-jejunal bypass liner (DJBL) patients regarding steatosis, fibrosis, and NASH. METHODS: Consecutive DJBL patients with type 2 diabetes underwent standardized assessments up to device removal at 48 weeks. These included aspartate and alanine transaminase (AST, ALT), controlled attenuation parameter (CAP, for steatosis), and liver stiffness measurement (LSM, for fibrosis). The NAFLD fibrosis score (NFS), fibrosis-4 score (FIB4), and enhanced liver fibrosis (ELF) test were also used to assess fibrosis and the Fibroscan-AST (FAST) score to assess NASH. Mixed models were used and missing data were accounted for with multiple imputation. RESULTS: Thirty-two patients (18 female, mean age 55.1, mean BMI 40.2 kg/m2) were included. After 48 weeks, the change compared to baseline with 95% CI was a factor 0.74 (0.65 to 0.84) for AST, 0.63 (0.53 to 0.75) for ALT, and a difference of - 0.21 (- 0.28 to - 0.13) for FAST, all with p < 0.001. Fibrosis based on LSM, NFS, and ELF did not change whereas FIB4 exhibited slight improvement. Eight DJBL were explanted early due to device-related complications and eight complications led to hospitalization. CONCLUSIONS: One year of DJBL therapy is associated with relevant improvements in non-invasive markers of steatosis and NASH, but not fibrosis, and is accompanied by a substantial number of complications. Given the lack of alternatives, DJBL deserves further attention.


Asunto(s)
Cirugía Bariátrica , Diabetes Mellitus Tipo 2 , Diagnóstico por Imagen de Elasticidad , Enfermedad del Hígado Graso no Alcohólico , Obesidad Mórbida , Aspartato Aminotransferasas , Cirugía Bariátrica/efectos adversos , Biomarcadores , Diabetes Mellitus Tipo 2/complicaciones , Femenino , Fibrosis , Humanos , Cirrosis Hepática/complicaciones , Persona de Mediana Edad , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Enfermedad del Hígado Graso no Alcohólico/cirugía , Obesidad Mórbida/cirugía
20.
Eur Heart J ; 31(1): 112-9, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19793768

RESUMEN

AIMS: Patients with type 2 diabetes mellitus (T2DM) suffer from accelerated coronary artery disease. We assessed the effects of a multifactorial intervention with focus on exercise training on coronary endothelial function, vascular structure, and inflammation in serum and skeletal muscle biopsies, including mRNA expression of diabetes candidate genes. METHODS AND RESULTS: Twenty-three patients were randomized to either 4 weeks in-hospital exercise training (6 x 15 min bicycle/day, 5 days/week) and a hypocaloric diet, followed by a 5 months ambulatory program (30 min ergometer/day, 5 days/week, plus 1 h group exercise/week), or a control group. At the beginning of the study, at 4 weeks, and after 6 months changes in diameter of coronary arteries in response to acetylcholine and mean peak flow velocity were invasively measured; intramural plaques were assessed by intravascular ultrasound. Six months of intervention led to significant improvement of coronary endothelial function, whereas intramural plaque burden remained unchanged. After 4 weeks, endothelial function remained unchanged, however, lowest values for fasting glucose, HbA1c, high-sensitive C-reactive protein, total and LDL-cholesterol, and highest values for mRNA expression in skeletal muscle of p22, gp91, haem oxygenase 1, peroxisome proliferator activator receptor (PPAR) alpha and gamma were observed. There was a continuous increase for AdipoR1, AdipoR2, Glut4, interleukin-6, endothelial nitric oxide synthase, and PPARgamma-coactivator-1alpha mRNA expression in skeletal muscle. CONCLUSION: This is the first study to demonstrate improvement in coronary endothelial function by a multifactorial intervention which focused on exercise training in patients with T2DM. This coincided with improved markers of hyperglycaemia, insulin sensitivity, and inflammation both in serum and skeletal muscle biopsies.


Asunto(s)
Enfermedad de la Arteria Coronaria/terapia , Diabetes Mellitus Tipo 2/terapia , Angiopatías Diabéticas/terapia , Endotelio Vascular/fisiopatología , Terapia por Ejercicio/métodos , Biomarcadores/sangre , Glucemia/metabolismo , Peso Corporal , Enfermedad de la Arteria Coronaria/metabolismo , Enfermedad de la Arteria Coronaria/fisiopatología , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/fisiopatología , Dislipidemias/terapia , Femenino , Humanos , Metabolismo de los Lípidos , Masculino , Músculo Esquelético/metabolismo , ARN Mensajero/metabolismo , Ultrasonografía Intervencional
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