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1.
Am J Hum Genet ; 111(4): 729-741, 2024 04 04.
Artículo en Inglés | MEDLINE | ID: mdl-38579670

RESUMEN

Glutamine synthetase (GS), encoded by GLUL, catalyzes the conversion of glutamate to glutamine. GS is pivotal for the generation of the neurotransmitters glutamate and gamma-aminobutyric acid and is the primary mechanism of ammonia detoxification in the brain. GS levels are regulated post-translationally by an N-terminal degron that enables the ubiquitin-mediated degradation of GS in a glutamine-induced manner. GS deficiency in humans is known to lead to neurological defects and death in infancy, yet how dysregulation of the degron-mediated control of GS levels might affect neurodevelopment is unknown. We ascertained nine individuals with severe developmental delay, seizures, and white matter abnormalities but normal plasma and cerebrospinal fluid biochemistry with de novo variants in GLUL. Seven out of nine were start-loss variants and two out of nine disrupted 5' UTR splicing resulting in splice exclusion of the initiation codon. Using transfection-based expression systems and mass spectrometry, these variants were shown to lead to translation initiation of GS from methionine 18, downstream of the N-terminal degron motif, resulting in a protein that is stable and enzymatically competent but insensitive to negative feedback by glutamine. Analysis of human single-cell transcriptomes demonstrated that GLUL is widely expressed in neuro- and glial-progenitor cells and mature astrocytes but not in post-mitotic neurons. One individual with a start-loss GLUL variant demonstrated periventricular nodular heterotopia, a neuronal migration disorder, yet overexpression of stabilized GS in mice using in utero electroporation demonstrated no migratory deficits. These findings underline the importance of tight regulation of glutamine metabolism during neurodevelopment in humans.


Asunto(s)
Epilepsia Generalizada , Glutamato-Amoníaco Ligasa , Glutamina , Animales , Humanos , Ratones , Encéfalo/metabolismo , Epilepsia Generalizada/genética , Glutamato-Amoníaco Ligasa/genética , Glutamato-Amoníaco Ligasa/metabolismo , Glutamatos/metabolismo , Glutamina/genética , Glutamina/metabolismo
2.
Genet Med ; 26(6): 101120, 2024 06.
Artículo en Inglés | MEDLINE | ID: mdl-38469793

RESUMEN

PURPOSE: Imbalances in protein homeostasis affect human brain development, with the ubiquitin-proteasome system (UPS) and autophagy playing crucial roles in neurodevelopmental disorders (NDD). This study explores the impact of biallelic USP14 variants on neurodevelopment, focusing on its role as a key hub connecting UPS and autophagy. METHODS: Here, we identified biallelic USP14 variants in 4 individuals from 3 unrelated families: 1 fetus, a newborn with a syndromic NDD and 2 siblings affected by a progressive neurological disease. Specifically, the 2 siblings from the latter family carried 2 compound heterozygous variants c.8T>C p.(Leu3Pro) and c.988C>T p.(Arg330∗), whereas the fetus had a homozygous frameshift c.899_902del p.(Lys300Serfs∗24) variant, and the newborn patient harbored a homozygous frameshift c.233_236del p.(Leu78Glnfs∗11) variant. Functional studies were conducted using sodium dodecyl-sulfate polyacrylamide gel electrophoresis, western blotting, and mass spectrometry analyses in both patient-derived and CRISPR-Cas9-generated cells. RESULTS: Our investigations indicated that the USP14 variants correlated with reduced N-terminal methionine excision, along with profound alterations in proteasome, autophagy, and mitophagy activities. CONCLUSION: Biallelic USP14 variants in NDD patients perturbed protein degradation pathways, potentially contributing to disorder etiology. Altered UPS, autophagy, and mitophagy activities underscore the intricate interplay, elucidating their significance in maintaining proper protein homeostasis during brain development.


Asunto(s)
Trastornos del Neurodesarrollo , Humanos , Trastornos del Neurodesarrollo/genética , Trastornos del Neurodesarrollo/patología , Femenino , Masculino , Alelos , Autofagia/genética , Ubiquitina Tiolesterasa/genética , Recién Nacido , Complejo de la Endopetidasa Proteasomal/genética , Linaje , Homocigoto , Predisposición Genética a la Enfermedad , Mutación/genética
3.
PLoS Genet ; 17(2): e1009306, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33635866

RESUMEN

Axonemal protein complexes, such as outer (ODA) and inner (IDA) dynein arms, are responsible for the generation and regulation of flagellar and ciliary beating. Studies in various ciliated model organisms have shown that axonemal dynein arms are first assembled in the cell cytoplasm and then delivered into axonemes during ciliogenesis. In humans, mutations in genes encoding for factors involved in this process cause structural and functional defects of motile cilia in various organs such as the airways and result in the hereditary disorder primary ciliary dyskinesia (PCD). Despite extensive knowledge about the cytoplasmic assembly of axonemal dynein arms in respiratory cilia, this process is still poorly understood in sperm flagella. To better define its clinical relevance on sperm structure and function, and thus male fertility, further investigations are required. Here we report the fertility status in different axonemal dynein preassembly mutant males (DNAAF2/ KTU, DNAAF4/ DYX1C1, DNAAF6/ PIH1D3, DNAAF7/ZMYND10, CFAP300/C11orf70 and LRRC6). Besides andrological examinations, we functionally and structurally analyzed sperm flagella of affected individuals by high-speed video- and transmission electron microscopy as well as systematically compared the composition of dynein arms in sperm flagella and respiratory cilia by immunofluorescence microscopy. Furthermore, we analyzed the flagellar length in dynein preassembly mutant sperm. We found that the process of axonemal dynein preassembly is also critical in sperm, by identifying defects of ODAs and IDAs in dysmotile sperm of these individuals. Interestingly, these mutant sperm consistently show a complete loss of ODAs, while some respiratory cilia from the same individual can retain ODAs in the proximal ciliary compartment. This agrees with reports of solely one distinct ODA type in sperm, compared to two different ODA types in proximal and distal respiratory ciliary axonemes. Consistent with observations in model organisms, we also determined a significant reduction of sperm flagellar length in these individuals. These findings are relevant to subsequent studies on the function and composition of sperm flagella in PCD patients and non-syndromic infertile males. Our study contributes to a better understanding of the fertility status in PCD-affected males and should help guide genetic and andrological counselling for affected males and their families.


Asunto(s)
Dineínas Axonemales/metabolismo , Axonema/metabolismo , Cilios/metabolismo , Flagelos/metabolismo , Infertilidad Masculina/metabolismo , Espermatozoides/metabolismo , Dineínas Axonemales/genética , Dineínas Axonemales/ultraestructura , Axonema/genética , Axonema/ultraestructura , Cilios/genética , Estudios de Cohortes , Citoplasma/metabolismo , Proteínas del Citoesqueleto/genética , Proteínas del Citoesqueleto/metabolismo , Flagelos/genética , Flagelos/ultraestructura , Humanos , Infertilidad Masculina/genética , Péptidos y Proteínas de Señalización Intracelular/genética , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Masculino , Microscopía Electrónica de Transmisión , Mutación , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Espermatozoides/ultraestructura
4.
Euro Surveill ; 29(13)2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38551095

RESUMEN

BackgroundScarce European data in early 2021 suggested lower vaccine effectiveness (VE) against SARS-CoV-2 Omicron lineages than previous variants.AimWe aimed to estimate primary series (PS) and first booster VE against symptomatic BA.1/BA.2 infection and investigate potential biases.MethodsThis European test-negative multicentre study tested primary care patients with acute respiratory symptoms for SARS-CoV-2 in the BA.1/BA.2-dominant period. We estimated PS and booster VE among adults and adolescents (PS only) for all products combined and for Comirnaty alone, by time since vaccination, age and chronic condition. We investigated potential bias due to correlation between COVID-19 and influenza vaccination and explored effect modification and confounding by prior SARS-CoV-2 infection.ResultsAmong adults, PS VE was 37% (95% CI: 24-47%) overall and 60% (95% CI: 44-72%), 43% (95% CI: 26-55%) and 29% (95% CI: 13-43%) < 90, 90-179 and ≥ 180 days post vaccination, respectively. Booster VE was 42% (95% CI: 32-51%) overall and 56% (95% CI: 47-64%), 22% (95% CI: 2-38%) and 3% (95% CI: -78% to 48%), respectively. Primary series VE was similar among adolescents. Restricting analyses to Comirnaty had little impact. Vaccine effectiveness was higher among older adults. There was no signal of bias due to correlation between COVID-19 and influenza vaccination. Confounding by previous infection was low, but sample size precluded definite assessment of effect modification.ConclusionPrimary series and booster VE against symptomatic infection with BA.1/BA.2 ranged from 37% to 42%, with similar waning post vaccination. Comprehensive data on previous SARS-CoV-2 infection would help disentangle vaccine- and infection-induced immunity.


Asunto(s)
COVID-19 , Gripe Humana , Humanos , Adolescente , Anciano , Vacunas contra la COVID-19 , COVID-19/epidemiología , COVID-19/prevención & control , SARS-CoV-2 , Vacuna BNT162 , Gripe Humana/epidemiología , Gripe Humana/prevención & control , Eficacia de las Vacunas , Europa (Continente)/epidemiología , Atención Primaria de Salud
5.
Genet Med ; 25(7): 100838, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37057673

RESUMEN

PURPOSE: Mechanistic target of rapamycin (mTOR) complex 1 (mTORC1) regulates cell growth in response to nutritional status. Central to the mTORC1 function is the Rag-GTPase heterodimer. One component of the Rag heterodimer is RagC (Ras-related GTP-binding protein C), which is encoded by the RRAGC gene. METHODS: Genetic testing via trio exome sequencing was applied to identify the underlying disease cause in 3 infants with dilated cardiomyopathy, hepatopathy, and brain abnormalities, including pachygyria, polymicrogyria, and septo-optic dysplasia. Studies in patient-derived skin fibroblasts and in a HEK293 cell model were performed to investigate the cellular consequences. RESULTS: We identified 3 de novo missense variants in RRAGC (NM_022157.4: c.269C>A, p.(Thr90Asn), c.353C>T, p.(Pro118Leu), and c.343T>C, p.(Trp115Arg)), which were previously reported as occurring somatically in follicular lymphoma. Studies of patient-derived fibroblasts carrying the p.(Thr90Asn) variant revealed increased cell size, as well as dysregulation of mTOR-related p70S6K (ribosomal protein S6 kinase 1) and transcription factor EB signaling. Moreover, subcellular localization of mTOR was decoupled from metabolic state. We confirmed the key findings for all RRAGC variants described in this study in a HEK293 cell model. CONCLUSION: The above results are in line with a constitutive overactivation of the mTORC1 pathway. Our study establishes de novo missense variants in RRAGC as cause of an early-onset mTORopathy with unfavorable prognosis.


Asunto(s)
Diana Mecanicista del Complejo 1 de la Rapamicina , Proteínas de Unión al GTP Monoméricas , Serina-Treonina Quinasas TOR , Humanos , Lactante , Fibroblastos/metabolismo , Enfermedades Genéticas Congénitas/genética , Células HEK293 , Diana Mecanicista del Complejo 1 de la Rapamicina/genética , Proteínas de Unión al GTP Monoméricas/genética , Proteínas de Unión al GTP Monoméricas/metabolismo , Complejos Multiproteicos/genética , Mutación Missense , Serina-Treonina Quinasas TOR/genética , Serina-Treonina Quinasas TOR/metabolismo
6.
Euro Surveill ; 28(47)2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37997665

RESUMEN

IntroductionThe I-MOVE-COVID-19 and VEBIS hospital networks have been measuring COVID-19 vaccine effectiveness (VE) in participating European countries since early 2021.AimWe aimed to measure VE against PCR-confirmed SARS-CoV-2 in patients ≥ 20 years hospitalised with severe acute respiratory infection (SARI) from December 2021 to July 2022 (Omicron-dominant period).MethodsIn both networks, 46 hospitals (13 countries) follow a similar test-negative case-control protocol. We defined complete primary series vaccination (PSV) and first booster dose vaccination as last dose of either vaccine received ≥ 14 days before symptom onset (stratifying first booster into received < 150 and ≥ 150 days after last PSV dose). We measured VE overall, by vaccine category/product, age group and time since first mRNA booster dose, adjusting by site as a fixed effect, and by swab date, age, sex, and presence/absence of at least one commonly collected chronic condition.ResultsWe included 2,779 cases and 2,362 controls. The VE of all vaccine products combined against hospitalisation for laboratory-confirmed SARS-CoV-2 was 43% (95% CI: 29-54) for complete PSV (with last dose received ≥ 150 days before onset), while it was 59% (95% CI: 51-66) after addition of one booster dose. The VE was 85% (95% CI: 78-89), 70% (95% CI: 61-77) and 36% (95% CI: 17-51) for those with onset 14-59 days, 60-119 days and 120-179 days after booster vaccination, respectively.ConclusionsOur results suggest that, during the Omicron period, observed VE against SARI hospitalisation improved with first mRNA booster dose, particularly for those having symptom onset < 120 days after first booster dose.


Asunto(s)
COVID-19 , Neumonía , Humanos , Adulto , COVID-19/prevención & control , Vacunas contra la COVID-19 , Eficacia de las Vacunas , SARS-CoV-2 , Hospitalización , Europa (Continente)/epidemiología , ARN Mensajero
7.
Z Gastroenterol ; 2023 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-37871633

RESUMEN

Liver injury associated with selective androgen receptor modulators (SARMs) is an issue that has not been reported often. We report a case of a previously healthy 24-year-old male, who was referred to our hospital for severe jaundice with intense pruritus. He had previously taken the SARM Enobosarm (also known as Ostarine) for muscle-building purposes. Blood serum levels of total bilirubin exceeded 30 mg/dL with only a slight elevation of liver enzymes. Liver biopsy revealed isolated hepatocellular cholestasis (bland cholestasis) with limited inflammation or necrosis. Supportive treatment was begun in our hospital with molecular adsorbent recirculation system (MARS) albumin dialysis, as well as cholestyramine for pruritus relief. During therapy, bilirubin levels and symptoms regressed, and after five sessions of dialysis, the patient could be released from our clinic in a markedly improved clinical and laboratory condition. However, bilirubin parameters regressed slowly after this, reaching normal levels as late as six months after first intake of the compound. Exome-based genetic testing brought about no pathogenic variants for cholestatic liver disease in our patient. Nevertheless, three common heterozygous polymorphisms associated with an increased risk for intrahepatic cholestasis could be identified. Our case demonstrates that SARMs can cause severe liver injuries not prominently mentioned in safety data sheets. Therefore, these compounds constitute a potential danger to the user's health. This holds especially true when taking SARMs without supervision by a medical professional, which should consist of a thorough monitoring of liver enzyme and bilirubin levels.

8.
Clin Genet ; 102(2): 98-109, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35616059

RESUMEN

Biallelic variants of the gene encoding for the zinc-finger protein 142 (ZNF142) have recently been associated with intellectual disability (ID), speech impairment, seizures, and movement disorders in nine individuals from five families. In this study, we obtained phenotype and genotype information of 26 further individuals from 16 families. Among the 27 different ZNF142 variants identified in the total of 35 individuals only four were missense. Missense variants may give a milder phenotype by changing the local structure of ZF motifs as suggested by protein modeling; but this correlation should be validated in larger cohorts and pathogenicity of the missense variants should be investigated with functional studies. Clinical features of the 35 individuals suggest that biallelic ZNF142 variants lead to a syndromic neurodevelopmental disorder with mild to moderate ID, varying degrees of delay in language and gross motor development, early onset seizures, hypotonia, behavioral features, movement disorders, and facial dysmorphism. The differences in symptom frequencies observed in the unpublished individuals compared to those of published, and recognition of previously underemphasized facial features are likely to be due to the small sizes of the previous cohorts, which underlines the importance of larger cohorts for the phenotype descriptions of rare genetic disorders.


Asunto(s)
Discapacidad Intelectual , Trastornos del Movimiento , Trastornos del Neurodesarrollo , Factores de Transcripción , Humanos , Discapacidad Intelectual/diagnóstico , Trastornos del Movimiento/complicaciones , Trastornos del Neurodesarrollo/genética , Fenotipo , Convulsiones/complicaciones , Convulsiones/genética , Factores de Transcripción/genética
9.
BMC Cancer ; 22(1): 706, 2022 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-35761208

RESUMEN

BACKGROUND: Clinical management of women carrying a germline pathogenic variant (PV) in the BRCA1/2 genes demands for accurate age-dependent estimators of breast cancer (BC) risks, which were found to be affected by a variety of intrinsic and extrinsic factors. Here we assess the contribution of polygenic risk scores (PRSs) to the occurrence of extreme phenotypes with respect to age at onset, namely, primary BC diagnosis before the age of 35 years (early diagnosis, ED) and cancer-free survival until the age of 60 years (late/no diagnosis, LD) in female BRCA1/2 PV carriers. METHODS: Overall, estrogen receptor (ER)-positive, and ER-negative BC PRSs as developed by Kuchenbaecker et al. for BC risk discrimination in female BRCA1/2 PV carriers were employed for PRS computation in a curated sample of 295 women of European descent carrying PVs in the BRCA1 (n=183) or the BRCA2 gene (n=112), and did either fulfill the ED criteria (n=162, mean age at diagnosis: 28.3 years, range: 20 to 34 years) or the LD criteria (n=133). Binomial logistic regression was applied to assess the association of standardized PRSs with either ED or LD under adjustment for patient recruitment criteria for germline testing and localization of BRCA1/2 PVs in the corresponding BC or ovarian cancer (OC) cluster regions. RESULTS: For BRCA1 PV carriers, the standardized overall BC PRS displayed the strongest association with ED (odds ratio (OR) = 1.62; 95% confidence interval (CI): 1.16-2.31, p<0.01). Additionally, statistically significant associations of selection for the patient recruitment criteria for germline testing and localization of pathogenic PVs outside the BRCA1 OC cluster region with ED were observed. For BRCA2 PV carriers, the standardized PRS for ER-negative BC displayed the strongest association (OR = 2.27, 95% CI: 1.45-3.78, p<0.001). CONCLUSIONS: PRSs contribute to the development of extreme phenotypes of female BRCA1/2 PV carriers with respect to age at primary BC diagnosis. Construction of optimized PRS SNP sets for BC risk stratification in BRCA1/2 PV carriers should be the task of future studies with larger, well-defined study samples. Furthermore, our results provide further evidence, that localization of PVs in BC/OC cluster regions might be considered in BC risk calculations for unaffected BRCA1/2 PV carriers.


Asunto(s)
Neoplasias de la Mama , Neoplasias Ováricas , Edad de Inicio , Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias de la Mama/patología , Femenino , Genes BRCA2 , Predisposición Genética a la Enfermedad , Humanos , Mutación , Neoplasias Ováricas/genética , Factores de Riesgo
10.
Mol Pharm ; 19(5): 1540-1547, 2022 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-35393854

RESUMEN

Treatment of age-related macular degeneration (AMD) with anti-vascular endothelial growth factor (VEGF) biologic agents has been shown to restore and maintain visual acuity for many patients afflicted with wet AMD. These agents are usually administered via intravitreal injection at a dosing interval of 4-8 weeks. Employment of long-acting delivery (LAD) technologies could improve the therapeutic outcome, ensure timely treatment, and reduce burden on patients, caregivers, and the health care system. Development of LAD approaches requires thorough testing in pre-clinical species; however, therapeutic proteins of human origin may not be well tolerated during testing in non-human species due to immunogenicity. Here, we have engineered a surrogate porcine antibody Fab fragment (pigG6.31) from a human antibody for testing ocular LAD technologies in a porcine model. The engineered Fab retains the VEGF-A-binding and inhibition properties of the parental human Fab and has stability properties suitable for LAD evaluation. Upon intravitreal injection in minipigs, pigG6.31 showed first-order clearance from the ocular compartments with vitreal elimination rates consistent with other molecules of this size. Application of the surrogate molecule in an in vivo evaluation in minipigs of a prototype of the port delivery (PD) platform indicated continuous ocular delivery from the implant, with release kinetics consistent with both the results from in vitro release studies and the efficacy observed in human clinical studies of the PD system with ranibizumab (PDS). Anti-drug antibodies in the serum against pigG6.31 were not detected over exposure durations up to 16 weeks, suggesting that this molecule has low porcine immunogenicity.


Asunto(s)
Inhibidores de la Angiogénesis , Degeneración Macular Húmeda , Animales , Humanos , Fragmentos Fab de Inmunoglobulinas/uso terapéutico , Inyecciones Intravítreas , Ingeniería de Proteínas , Ranibizumab/uso terapéutico , Porcinos , Porcinos Enanos/metabolismo , Tecnología , Factor A de Crecimiento Endotelial Vascular/metabolismo , Degeneración Macular Húmeda/tratamiento farmacológico
11.
Breast Cancer Res ; 21(1): 55, 2019 04 29.
Artículo en Inglés | MEDLINE | ID: mdl-31036035

RESUMEN

BACKGROUND: The role of the BARD1 gene in breast cancer (BC) and ovarian cancer (OC) predisposition remains elusive, as published case-control investigations have revealed controversial results. We aimed to assess the role of deleterious BARD1 germline variants in BC/OC predisposition in a sample of 4920 BRCA1/2-negative female BC/OC index patients of the German Consortium for Hereditary Breast and Ovarian Cancer (GC-HBOC). METHODS: A total of 4469 female index patients with BC, 451 index patients with OC, and 2767 geographically matched female control individuals were screened for loss-of-function (LoF) mutations and potentially damaging rare missense variants in BARD1. All patients met the inclusion criteria of the GC-HBOC for germline testing and reported at least one relative with BC or OC. Additional control datasets (Exome Aggregation Consortium, ExAC; Fabulous Ladies Over Seventy, FLOSSIES) were included for the calculation of odds ratios (ORs). RESULTS: We identified LoF variants in 23 of 4469 BC index patients (0.51%) and in 36 of 37,265 control individuals (0.10%), resulting in an OR of 5.35 (95% confidence interval [CI] = 3.17-9.04; P < 0.00001). BARD1-mutated BC index patients showed a significantly younger mean age at first diagnosis (AAD; 42.3 years, range 24-60 years) compared with the overall study sample (48.6 years, range 17-92 years; P = 0.00347). In the subgroup of BC index patients with an AAD < 40 years, an OR of 12.04 (95% CI = 5.78-25.08; P < 0.00001) was observed. An OR of 7.43 (95% CI = 4.26-12.98; P < 0.00001) was observed when stratified for an AAD < 50 years. LoF variants in BARD1 were not significantly associated with BC in the subgroup of index patients with an AAD ≥ 50 years (OR = 2.29; 95% CI = 0.82-6.45; P = 0.11217). Overall, rare and predicted damaging BARD1 missense variants were significantly more prevalent in BC index patients compared with control individuals (OR = 2.15; 95% CI = 1.26-3.67; P = 0.00723). Neither LoF variants nor predicted damaging rare missense variants in BARD1 were identified in 451 familial index patients with OC. CONCLUSIONS: Due to the significant association of germline LoF variants in BARD1 with early-onset BC, we suggest that intensified BC surveillance programs should be offered to women carrying pathogenic BARD1 gene variants.


Asunto(s)
Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/genética , Predisposición Genética a la Enfermedad , Mutación de Línea Germinal , Mutación con Pérdida de Función , Proteínas Supresoras de Tumor/genética , Ubiquitina-Proteína Ligasas/genética , Adolescente , Adulto , Edad de Inicio , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Asociación Genética , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Persona de Mediana Edad , Oportunidad Relativa , Neoplasias Ováricas/epidemiología , Neoplasias Ováricas/genética , Prevalencia , Adulto Joven
12.
Acc Chem Res ; 51(12): 3183-3190, 2018 12 18.
Artículo en Inglés | MEDLINE | ID: mdl-30412377

RESUMEN

Since Alan Turing's 1952 pioneering work, reaction-diffusion (RD) processes are regarded as prototype mechanisms for pattern formation in living systems. Though suspected in many aspects of morphogenetic development, pure RD patterns have not yet been demonstrated in living organisms. The first observations of an autonomous development of stationary chemical patterns were made in the early 1990s. In this Account, we discuss the recent developments for producing stationary pH RD patterns in open spatial reactors. The theoretical analysis of the early experiments anticipated the possibility of finding Turing patterns in a wide range of oscillatory reactions if one could control the kinetic and diffusional rate of some key species. However, no experimentally effective method to produce stationary Turing patterns was attained before 2009, and the number of systems stagnated at two until then. The two precursor reaction systems benefited from unplanned favorable chemical properties of the RD media. Theoretical studies point out that appropriate diffusion rate differences are necessary to produce stationary patterns since a competition between an effective short distance self-activation and a long distance inhibitory process is required. This differential diffusion would naturally lead to differential exchange rates between the RD system and its feed environment, an aspect somewhat overlooked in theoretical and in primal experimental approaches. Our pattern design method takes this aspect into account. A slower diffusion of a self-activated species (here, protons), produced in the RD part of the spatial reactor, generates the accumulation of this species compared to the other species. This accumulation has to be at least partly compensated by an independent scavenging reaction. The above requirement naturally brought us to focus on two-substrate pH oscillatory reactions. Stationary RD patterns are now well documented in six pH driven reaction systems. Furthermore, the coupling with a pH dependent metal ion complexing agent led to stationary patterns in calcium ion concentration. Our effective semiempirical design method does not require a detailed knowledge of the reaction kinetics; thus it is applicable to a broad spectrum of reactions and even to synthetic biological systems. It is based on simple dynamic arguments and on general topological characteristics of a nonequilibrium phase diagram. We first illustrate our method with numerical simulations, based on a realistic but idealized general model of the two-substrate pH-oscillator reaction family, and provide a refined view of the topology of the resulting phase diagrams. Then, we exemplify its effectiveness by observations made in distinct pH self-activated systems. Analogies and differences between experiments and the model calculations are pointed out. Besides standard hexagonal arrays of spots and parallel stripes, hitherto undocumented dynamic phenomena, such as randomly blinking areas and complex dynamic and stationary filamentous structures, were observed. The main challenge, to find low-mobility complexing agents that would selectively and reversibly bind a species controlling the self-activatory kinetic path of the reaction, was readily overcome in multiple ways by anions of weak acids: not only by polymeric substances but in some cases by a pH color indicator or even smaller molecules, depending on their proton binding affinity.

13.
Breast Cancer Res ; 20(1): 7, 2018 01 24.
Artículo en Inglés | MEDLINE | ID: mdl-29368626

RESUMEN

BACKGROUND: Germline mutations in the BRIP1 gene have been described as conferring a moderate risk for ovarian cancer (OC), while the role of BRIP1 in breast cancer (BC) pathogenesis remains controversial. METHODS: To assess the role of deleterious BRIP1 germline mutations in BC/OC predisposition, 6341 well-characterized index patients with BC, 706 index patients with OC, and 2189 geographically matched female controls were screened for loss-of-function (LoF) mutations and potentially damaging missense variants. All index patients met the inclusion criteria of the German Consortium for Hereditary Breast and Ovarian Cancer for germline testing and tested negative for pathogenic BRCA1/2 variants. RESULTS: BRIP1 LoF mutations confer a high OC risk in familial index patients (odds ratio (OR) = 20.97, 95% confidence interval (CI) = 12.02-36.57, P < 0.0001) and in the subgroup of index patients with late-onset OC (OR = 29.91, 95% CI = 14.99-59.66, P < 0.0001). No significant association of BRIP1 LoF mutations with familial BC was observed (OR = 1.81 95% CI = 1.00-3.30, P = 0.0623). In the subgroup of familial BC index patients without a family history of OC there was also no apparent association (OR = 1.42, 95% CI = 0.70-2.90, P = 0.3030). In 1027 familial BC index patients with a family history of OC, the BRIP1 mutation prevalence was significantly higher than that observed in controls (OR = 3.59, 95% CI = 1.43-9.01; P = 0.0168). Based on the negative association between BRIP1 LoF mutations and familial BC in the absence of an OC family history, we conclude that the elevated mutation prevalence in the latter cohort was driven by the occurrence of OC in these families. Compared with controls, predicted damaging rare missense variants were significantly more prevalent in OC (P = 0.0014) but not in BC (P = 0.0693) patients. CONCLUSIONS: To avoid ambiguous results, studies aimed at assessing the impact of candidate predisposition gene mutations on BC risk might differentiate between BC index patients with an OC family history and those without. In familial cases, we suggest that BRIP1 is a high-risk gene for late-onset OC but not a BC predisposition gene, though minor effects cannot be excluded.


Asunto(s)
Neoplasias de la Mama/genética , Proteínas del Grupo de Complementación de la Anemia de Fanconi/genética , Predisposición Genética a la Enfermedad , Neoplasias Ováricas/genética , ARN Helicasas/genética , Adulto , Anciano , Neoplasias de la Mama/patología , Femenino , Estudios de Asociación Genética , Mutación de Línea Germinal , Humanos , Mutación con Pérdida de Función/genética , Persona de Mediana Edad , Neoplasias Ováricas/patología , Linaje , Factores de Riesgo
14.
Mov Disord ; 33(1): 169-173, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29266392

RESUMEN

BACKGROUND: We investigated the acute effect of short pulse widths on the therapeutic window in subthalamic nucleus deep brain stimulation in Parkinson's disease. METHODS: We assessed 10 PD patients with STN-DBS at a 60-µs pulse width. We randomly and double-blindedly applied 10- to 50-µs pulse widths. The principal outcome was the therapeutic window (difference between the amplitude thresholds for visible muscle contraction and for best rigidity control). The secondary outcome was the charge per pulse (which reflects the efficiency of the stimulation) needed to control rigidity. Two-way analysis of variance and pairwise t tests were applied. RESULTS: The therapeutic window widened when the pulse width shortened (r = -0.45; P < 0.001), and charge per pulse was reduced (P < 0.05). CONCLUSIONS: This randomized, double-blind study showed that shorter pulse widths widen the therapeutic window of STN-DBS in PD without increasing the electrical charge required to obtain the same acute clinical benefit. © 2017 International Parkinson and Movement Disorder Society.


Asunto(s)
Estimulación Encefálica Profunda/métodos , Enfermedad de Parkinson/terapia , Núcleo Subtalámico/fisiología , Biofisica , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Índice de Severidad de la Enfermedad , Estadísticas no Paramétricas , Resultado del Tratamiento
15.
Rev Med Suisse ; 14(604): 879-882, 2018 Apr 25.
Artículo en Francés | MEDLINE | ID: mdl-29701433

RESUMEN

Movement disorders of monogenic origin are rare. In case of a specific phenotype, classical targeted sequencing of the gene can be used. When the clinical picture is not well defined, or when there is genetic heterogeneity or a large differential diagnosis, high-throughput sequencing is a useful tool for the analysis of numerous genes simultaneously. To discuss which approach is optimal, a multidisciplinary consultation by a movement disorders specialist and a geneticist is recommended. For some genetic movement disorders there is specific treatment available. The most common movement disorders, such as Parkinson's disease and essential tremor, have probably a complex etiology, including polygenic and environmental factors. Less than 5 % of Parkinsonian patients have a monogenic, hereditary form of the disease.


Les mouvements anormaux (ou maladies extrapyramidales) d'origine monogénique sont rares. Quand le phénotype est spécifique, il est possible d'analyser le gène suspecté par séquençage ciblé. Lors d'atteinte mal définie, d'hétérogénéité génétique avérée ou de diagnostic différentiel large, le séquençage à haut débit permet d'analyser plusieurs gènes en même temps. Une consultation multidisciplinaire, par un neurologue spécialisé et un généticien, est alors recommandée. Pour une minorité des mouvements anormaux d'origine monogénique, il existe des traitements spécifiques. Les maladies extrapyramidales fréquentes, comme la maladie de Parkinson et le tremblement essentiel, ont le plus souvent une étiologie complexe (facteurs polygéniques et environnementaux). Moins de 5 % des patients parkinsoniens ont une forme monogénique, héréditaire.

16.
Rev Med Suisse ; 14(604): 888-891, 2018 Apr 25.
Artículo en Francés | MEDLINE | ID: mdl-29701435

RESUMEN

Unlike most basal ganglia disorders, which usually progress slowly and relentlessly, a number of movement disorders may develop as acute or subacute conditions. Their occurrence commonly prompts patients to rush into the emergency room. A proper diagnosis is not always straightforward and requires a detailed analysis of the movement disorder phenomenology and a thorough medication screening, as many of these acute situations may be iatrogenic and drug-related. An accurate identification of the problem may enable an effective management and an appropriate therapy. This article is an overview of three distinct movement disorder emergencies, namely acute dystonia, acute chorea, and acute complications that can be observed in Parkinson's disease. Each topic is illustrated with a case report.


Contrairement à la plupart des affections des ganglions de la base, qui évoluent généralement sur un mode lentement progressif, certains mouvements anormaux peuvent se développer sur un mode aigu ou subaigu, amenant les patients à consulter en urgence. Le diagnostic est souvent délicat. Il repose sur une analyse détaillée de la phénoménologie et une anamnèse médicamenteuse fouillée, dans la mesure où ces situations sont volontiers iatrogènes. Une identification correcte du problème permet souvent une thérapeutique efficace. Le présent article propose une mise au point de trois problématiques de ce type, à savoir la dystonie aiguë, la chorée aiguë et les complications aiguës que l'on peut observer dans la maladie de Parkinson. Chaque sujet est illustré par un cas clinique.

17.
Rev Med Suisse ; 14(604): 875-878, 2018 Apr 25.
Artículo en Francés | MEDLINE | ID: mdl-29701432

RESUMEN

Advanced Parkinson's disease (PD) is characterized by severe motor and non-motor complications that negatively impact on patients' autonomy and health-related quality of life. In early disease, the therapeutic strategy consists of gradual increase in dopaminergic treatment and levodopa dose fragmentation. In more advanced stages, this approach becomes insufficient and three therapeutic options can be considered: deep brain stimulation (DBS), continuous subcutaneous apomorphine infusion, and continuous levodopa/carbidopa intestinal gel infusion.


La maladie de Parkinson (MP) avancée est caractérisée par la présence de complications motrices et non motrices qui ont un impact significatif sur l'autonomie et la qualité de vie des patients. La stratégie thérapeutique consiste à fractionner le traitement dopaminergique, à recourir aux formes à libération prolongée, et aux inhibiteurs des enzymes de dégradation de la dopamine. Lorsque ces mesures sont insuffisantes, trois options thérapeutiques plus invasives peuvent être envisagées : la stimulation cérébrale profonde, la perfusion sous-cutanée continue d'apomorphine et l'administration intrajéjunale de gel de lévodopa/carbidopa. L'objectif de cet article est de décrire les indications, bénéfices et effets secondaires potentiels de ces traitements dits « complexes ¼.

18.
J Med Genet ; 53(7): 465-71, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-26928436

RESUMEN

PURPOSE: To characterise the prevalence of pathogenic germline mutations in BRCA1 and BRCA2 in families with breast cancer (BC) and ovarian cancer (OC) history. PATIENTS AND METHODS: Data from 21 401 families were gathered between 1996 and 2014 in a clinical setting in the German Consortium for Hereditary Breast and Ovarian Cancer, comprising full pedigrees with cancer status of all individual members at the time of first counselling, and BRCA1/2 mutation status of the index patient. RESULTS: The overall BRCA1/2 mutation prevalence was 24.0% (95% CI 23.4% to 24.6%). Highest mutation frequencies were observed in families with at least two OCs (41.9%, 95% CI 36.1% to 48.0%) and families with at least one breast and one OC (41.6%, 95% CI 40.3% to 43.0%), followed by male BC with at least one female BC or OC (35.8%; 95% CI 32.2% to 39.6%). In families with a single case of early BC (<36 years), mutations were found in 13.7% (95% CI 11.9% to 15.7%). Postmenopausal unilateral or bilateral BC did not increase the probability of mutation detection. Occurrence of premenopausal BC and OC in the same woman led to higher mutation frequencies compared with the occurrence of these two cancers in different individuals (49.0%; 95% CI 41.0% to 57.0% vs 31.5%; 95% CI 28.0% to 35.2%). CONCLUSIONS: Our data provide guidance for healthcare professionals and decision-makers to identify individuals who should undergo genetic testing for hereditary breast and ovarian cancer. Moreover, it supports informed decision-making of counselees on the uptake of genetic testing.


Asunto(s)
Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias de la Mama Masculina/genética , Neoplasias de la Mama/genética , Mutación de Línea Germinal/genética , Neoplasias Ováricas/genética , Adulto , Femenino , Predisposición Genética a la Enfermedad/genética , Pruebas Genéticas/métodos , Humanos , Masculino , Persona de Mediana Edad , Prevalencia
19.
Cerebellum ; 15(6): 829-831, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-26607151

RESUMEN

Progressive ataxia with palatal tremor (PAPT) is a syndrome caused by cerebellar and brainstem lesions involving the dentato-rubro-olivary tract and associated with hypertrophic olivary degeneration. Etiologies include acquired posterior fossa lesions (e.g. tumors, superficial siderosis, and inflammatory diseases) and genetic disorders, such as glial fibrillary acidic protein (GFAP) and polymerase gamma (POLG) mutations. We describe the case of a 52-year-old man who developed pure progressive ataxia and palatal tremor. Genetic analysis has shown that he is compound heterozygote for a known pathogenic (W748S) and a novel POLG variant (I1185N). Patients with POLG recessive mutations usually manifest a more complex clinical picture, including polyneuropathy and epilepsy; our case emphasizes the need to consider a genetic origin in a seemingly sporadic and pure PAPT.


Asunto(s)
Ataxia/genética , Enfermedades Cerebelosas/genética , ADN Polimerasa Dirigida por ADN/genética , Enfermedades Mitocondriales/genética , Mutación , Temblor/genética , Ataxia/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Enfermedades Cerebelosas/diagnóstico por imagen , ADN Polimerasa gamma , Diagnóstico Diferencial , Humanos , Masculino , Persona de Mediana Edad , Enfermedades Mitocondriales/diagnóstico por imagen , Fenotipo , Síndrome , Temblor/diagnóstico por imagen
20.
Euro Surveill ; 21(7): pii=30139, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26924024

RESUMEN

Influenza A(H3N2), A(H1N1)pdm09 and B viruses co-circulated in Europe in 2014/15. We undertook a multicentre case-control study in eight European countries to measure 2014/15 influenza vaccine effectiveness (VE) against medically-attended influenza-like illness (ILI) laboratory-confirmed as influenza. General practitioners swabbed all or a systematic sample of ILI patients. We compared the odds of vaccination of ILI influenza positive patients to negative patients. We calculated adjusted VE by influenza type/subtype, and age group. Among 6,579 ILI patients included, 1,828 were A(H3N2), 539 A(H1N1)pdm09 and 1,038 B. VE against A(H3N2) was 14.4% (95% confidence interval (CI): -6.3 to 31.0) overall, 20.7% (95%CI: -22.3 to 48.5), 10.9% (95%CI -30.8 to 39.3) and 15.8% (95% CI: -20.2 to 41.0) among those aged 0-14, 15-59 and  ≥60 years, respectively. VE against A(H1N1)pdm09 was 54.2% (95%CI: 31.2 to 69.6) overall, 73.1% (95%CI: 39.6 to 88.1), 59.7% (95%CI: 10.9 to 81.8), and 22.4% (95%CI: -44.4 to 58.4) among those aged 0-14, 15-59 and  ≥60 years respectively. VE against B was 48.0% (95%CI: 28.9 to 61.9) overall, 62.1% (95%CI: 14.9 to 83.1), 41.4% (95%CI: 6.2 to 63.4) and 50.4% (95%CI: 14.6 to 71.2) among those aged 0-14, 15-59 and ≥60 years respectively. VE against A(H1N1)pdm09 and B was moderate. The low VE against A(H3N2) is consistent with the reported mismatch between circulating and vaccine strains.


Asunto(s)
Subtipo H1N1 del Virus de la Influenza A/inmunología , Subtipo H3N2 del Virus de la Influenza A/inmunología , Virus de la Influenza B/inmunología , Vacunas contra la Influenza/inmunología , Gripe Humana/prevención & control , Evaluación de Resultado en la Atención de Salud , Potencia de la Vacuna , Adolescente , Adulto , Anciano , Estudios de Casos y Controles , Niño , Preescolar , Europa (Continente)/epidemiología , Unión Europea , Femenino , Humanos , Lactante , Recién Nacido , Subtipo H1N1 del Virus de la Influenza A/aislamiento & purificación , Subtipo H3N2 del Virus de la Influenza A/aislamiento & purificación , Virus de la Influenza B/aislamiento & purificación , Vacunas contra la Influenza/administración & dosificación , Gripe Humana/epidemiología , Gripe Humana/virología , Laboratorios , Masculino , Persona de Mediana Edad , Vigilancia de la Población , Atención Primaria de Salud , Estaciones del Año , Sensibilidad y Especificidad , Vacunación/estadística & datos numéricos , Adulto Joven
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