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1.
Phys Rev Lett ; 130(8): 081402, 2023 Feb 24.
Article in English | MEDLINE | ID: mdl-36898092

ABSTRACT

The gravitational wave strain emitted by a perturbed black hole (BH) ringing down is typically modeled analytically using first-order BH perturbation theory. In this Letter, we show that second-order effects are necessary for modeling ringdowns from BH merger simulations. Focusing on the strain's (ℓ,m)=(4,4) angular harmonic, we show the presence of a quadratic effect across a range of binary BH mass ratios that agrees with theoretical expectations. We find that the quadratic (4,4) mode's amplitude exhibits quadratic scaling with the fundamental (2,2) mode-its parent mode. The nonlinear mode's amplitude is comparable to or even larger than that of the linear (4,4) mode. Therefore, correctly modeling the ringdown of higher harmonics-improving mode mismatches by up to 2 orders of magnitude-requires the inclusion of nonlinear effects.

2.
Rev. chil. pediatr ; 91(6): 908-916., dic. 2020. ilus, tab, graf
Article in Spanish | LILACS | ID: biblio-1508046

ABSTRACT

INTRODUCCIÓN: La inmunodeficiencia combinada severa (IDCS) corresponde a una de las formas más graves de inmunodeficiencia primaria, existiendo escasos datos nacionales sobre ésta. OBJETIVO: describir la epidemiología, complicaciones, pronóstico y uso de la vacuna BCG en pacientes chilenos con IDCS. PACIENTES Y MÉTODO: Estudio retrospectivo de pacientes diagnosticados con IDCS entre los años 1999 y 2020 por médicos inmunólogos a lo largo de Chile. El diagnóstico de IDCS se realizó conforme a los criterios propuestos por Shearer: linfocitos T (CD3+) < 300 células/μL y prolife ración 10% del límite de normalidad en respuesta a fitohemaglutinina o presencia de linfocitos T de origen materno. Se obtuvieron de la ficha clínica los datos correspondientes a: sexo, edad al diagnóstico, consanguinidad, región de origen, subpoblaciones linfocitarias, diagnóstico genético, complicaciones infecciosas y no infecciosas, vacunación BCG y sus complicaciones, edad de deriva ción al centro de TPH y causa de mortalidad no relacionada al TPH. RESULTADOS: se diagnosticaron 25 casos de IDCS en 22 familias entre los años 1999-2020. 78% varones, la edad media a la primera manifestación fue 2.3 meses (0-7), mientras que la edad media al diagnóstico fue de 3.4 meses (0 7). Un 16% de los casos tenía un antecedente familiar de IDCS. Un 40% de los casos fueron diag nosticados en la Región Metropolitana. El inmunofenotipo más frecuente fue T-B-NK+ (48%). Se realizaron estudios genéticos en 69,5% de los casos, siendo los defectos genéticos en RAG2 (39%) la causa más frecuente. Un 88% de los casos recibió la vacuna Bacillus Calmette-Guerin (BCG) previo al diagnóstico, incluidos 2 pacientes con historia familiar positiva, 36% de los vacunados experimentó complicaciones de la BCG. La edad media a la derivación a trasplante fue de 7,4 meses (5-16). De los 25 pacientes, 11 fallecieron previo a la derivación a un centro de trasplante. CONCLUSIÓN: En Chile existe un retraso clínicamente significativo entre las primeras manifestaciones y el diagnóstico de IDCS, así como un importante retraso en la derivación a centros de trasplante. La mayoría de los pacientes con IDCS reciben la vacuna BCG, pese a tener antecedentes familiares, y experimentan frecuentemente complicaciones de la vacuna.


INTRODUCTION: Severe combined immunodeficiency (SCID) is the most severe form of primary immunodeficiency. To date, there is little local information about this disease. OBJECTIVE: To describe the epidemiology, complications, prognosis, and use of the BCG vaccine in Chilean patients with SCID. PATIENTS AND METHOD: Retrospective review of the clinical records of patients diagnosed with SCID by clinical immunologists between 1999 and 2020 throughout Chile. SCID was diagnosed according to the cri teria proposed by Shearer: T lymphocytes (CD3+) < 300 cells/μL and proliferation 10% of the limit of normality in response to phytohemagglutinin or presence of T lymphocytes of maternal origin. Data collected from the clinical records were: sex, age at diagnosis, consanguinity, region of origin, lymphocyte subpopulations, genetic diagnosis, infectious and non-infectious complications, BCG vaccination and its complications, age at referral to the bone marrow transplant (BMT) center, and cause of non-BMT-related mortality. RESULTS: Between 1999 and 2020, 25 patients were diagnosed with SCID. 78% of them were male, mean age at first manifestation of the disease was 2.3 months (0-7), while the mean age at diagnosis was 3.4 months (0-7). 16% of patients had a family history of SCID. 40% of cases were diagnosed within the Metropolitan Region. The most frequent immuno- phenotype was T-B-NK+ SCID (48%). Genetic studies were done in 69.5% of cases, mutations in the RAG2 gene were the most common etiology of SCID (39%). 88% of SCID patients received the Bacillus Calmette-Guerin (BCG) vaccine before diagnosis, including 2 cases with a known family history of SCID. 36% of those who received the vaccine had BCG-related complications. The mean age at referral to a bone marrow transplant center was 7.4 months (5-16). 11/25 patients died before being transferred to a transplant center. DISCUSSION: There is a clinically significant delay between the first manifestations and the diagnosis of SCID in Chilean patients, as well as an important time gap between the diagnosis of SCID and referral to a center for BMT. Most SCID cases in Chile receive the BCG vaccine, despite a known family history of the disease, and frequently develop vaccine-related complications.


Subject(s)
Humans , Male , Female , Infant, Newborn , Infant , BCG Vaccine/administration & dosage , Vaccination/statistics & numerical data , Severe Combined Immunodeficiency/epidemiology , Prognosis , Time Factors , Nuclear Proteins/genetics , BCG Vaccine/adverse effects , T-Lymphocytes/immunology , Chile , Retrospective Studies , Bone Marrow Transplantation/statistics & numerical data , Vaccination/adverse effects , Severe Combined Immunodeficiency/immunology , Severe Combined Immunodeficiency/therapy , DNA-Binding Proteins/genetics , Delayed Diagnosis , Mutation
3.
Rev. Méd. Clín. Condes ; 31(3/4): 256-269, mayo.-ago. 2020. ilus, tab
Article in Spanish | LILACS | ID: biblio-1223737

ABSTRACT

Las vacunas son altamente efectivas en prevenir enfermedades infecciosas a través del desarrollo en el individuo de una respuesta inmune protectora, sin desarrollar la enfermedad. Los distintos tipos de vacunas producen diferentes tipos de respuestas inmunes y variadas estrategias se han desarrollado para mejorar esta respuesta. El sistema inmune sufre cambios con la edad y esta inmunosenecencia altera la capacidad de responder frente a ellas. Por otro lado, si bien el sistema inmune puede reconocer elementos presentes en las vacunas y montar respuestas de hipersensibilidad ante ellos, las alergias a las vacunas son raras, teniendo que distinguirlas adecuadamente de otro tipo de reacciones. En caso que un paciente presente una reacción compatible con alergia, es importante conocer todos los componentes de la vacuna para realizar un estudio adecuado.


Vaccines are highly effective in preventing infectious diseases through the development in the individual a protective immune response, without developing the disease. Different types of vaccines produce different types of immune responses, and varied strategies have been developed to improve this response. The immune system undergoes changes with age, and this inmunosenescence alters the ability to respond to them. On the other hand, although the immune system can recognize elements present in vaccines and establish hypersensitivity responses to them, vaccine allergies are rare, having to properly distinguish them from other types of reactions. In the event that a patient has an allergy-compatible reaction, it is important to know all the components of the vaccine to conduct a proper study.


Subject(s)
Humans , Vaccines/adverse effects , Vaccines/immunology , Immunization/adverse effects , Hypersensitivity/immunology , Immunity/immunology , Vaccines, Attenuated/adverse effects , Vaccines, Attenuated/immunology , Vaccines, Inactivated/adverse effects , Vaccines, Inactivated/immunology , Immunosenescence , Anaphylaxis/immunology , Antigens/immunology
4.
Phys Rev Lett ; 124(6): 061101, 2020 Feb 14.
Article in English | MEDLINE | ID: mdl-32109103

ABSTRACT

Cosmological models with a dynamical dark energy field typically lead to a modified propagation of gravitational waves via an effectively time-varying gravitational coupling G(t). The local variation of this coupling between the time of emission and detection can be probed with standard sirens. Here we discuss the role that lunar laser ranging (LLR) and binary pulsar constraints play in the prospects of constraining G(t) with standard sirens. In particular, we argue that LLR constrains the matter-matter gravitational coupling G_{N}(t), whereas binary pulsars and standard sirens constrain the quadratic kinetic gravity self-interaction G_{gw}(t). Generically, these two couplings could be different in alternative cosmological models, in which case LLR constraints are irrelevant for standard sirens. We use the Hulse-Taylor pulsar data and show that observations are highly insensitive to time variations of G_{gw}(t) yet highly sensitive to G_{N}(t). We thus conclude that future gravitational waves data will become the best probe to test G_{gw}(t), and will hence provide novel constraints on dynamical dark energy models.

5.
Rev Chil Pediatr ; 91(6): 908-916, 2020 Dec.
Article in Spanish | MEDLINE | ID: mdl-33861827

ABSTRACT

INTRODUCTION: Severe combined immunodeficiency (SCID) is the most severe form of primary immunodeficiency. To date, there is little local information about this disease. OBJECTIVE: To describe the epidemiology, complications, prognosis, and use of the BCG vaccine in Chilean patients with SCID. PATIENTS AND METHOD: Retrospective review of the clinical records of patients diagnosed with SCID by clinical immunologists between 1999 and 2020 throughout Chile. SCID was diagnosed according to the cri teria proposed by Shearer: T lymphocytes (CD3+) < 300 cells/µL and proliferation 10% of the limit of normality in response to phytohemagglutinin or presence of T lymphocytes of maternal origin. Data collected from the clinical records were: sex, age at diagnosis, consanguinity, region of origin, lymphocyte subpopulations, genetic diagnosis, infectious and non-infectious complications, BCG vaccination and its complications, age at referral to the bone marrow transplant (BMT) center, and cause of non-BMT-related mortality. RESULTS: Between 1999 and 2020, 25 patients were diagnosed with SCID. 78% of them were male, mean age at first manifestation of the disease was 2.3 months (0-7), while the mean age at diagnosis was 3.4 months (0-7). 16% of patients had a family history of SCID. 40% of cases were diagnosed within the Metropolitan Region. The most frequent immuno- phenotype was T-B-NK+ SCID (48%). Genetic studies were done in 69.5% of cases, mutations in the RAG2 gene were the most common etiology of SCID (39%). 88% of SCID patients received the Bacillus Calmette-Guerin (BCG) vaccine before diagnosis, including 2 cases with a known family history of SCID. 36% of those who received the vaccine had BCG-related complications. The mean age at referral to a bone marrow transplant center was 7.4 months (5-16). 11/25 patients died before being transferred to a transplant center. DISCUSSION: There is a clinically significant delay between the first manifestations and the diagnosis of SCID in Chilean patients, as well as an important time gap between the diagnosis of SCID and referral to a center for BMT. Most SCID cases in Chile receive the BCG vaccine, despite a known family history of the disease, and frequently develop vaccine-related complications.


Subject(s)
BCG Vaccine/administration & dosage , Severe Combined Immunodeficiency/epidemiology , Vaccination/statistics & numerical data , BCG Vaccine/adverse effects , Bone Marrow Transplantation/statistics & numerical data , Chile , DNA-Binding Proteins/genetics , Delayed Diagnosis , Female , Humans , Infant , Infant, Newborn , Male , Mutation , Nuclear Proteins/genetics , Prognosis , Retrospective Studies , Severe Combined Immunodeficiency/immunology , Severe Combined Immunodeficiency/therapy , T-Lymphocytes/immunology , Time Factors , Vaccination/adverse effects
7.
Front Pediatr ; 7: 303, 2019.
Article in English | MEDLINE | ID: mdl-31417880

ABSTRACT

Nuclear factor kappa-B subunit 2 (NF-κB2/p100/p52), encoded by NFKB2 (MIM: 164012) belongs to the NF-κB family of transcription factors that play a critical role in inflammation, immunity, cell proliferation, differentiation and survival. Heterozygous C-terminal mutations in NFKB2 have been associated with early-onset common variable immunodeficiency (CVID), central adrenal insufficiency and ectodermal dysplasia. Only two previously reported cases have documented decreased natural killer (NK) cell cytotoxicity, and little is known about the role of NF-κB2 in NK cell maturation and function. Here we report a 13-year-old female that presented at 6 years of age with a history of early onset recurrent sinopulmonary infections, progressive hair loss, and hypogamaglobulinemia consistent with a clinical diagnosis of CVID. At 9 years of age she had cytomegalovirus (CMV) pneumonia that responded to ganciclovir treatment. Functional NK cell testing demonstrated decreased NK cell cytotoxicity despite normal NK cell numbers, consistent with a greater susceptibility to systemic CMV infection. Research exome sequencing (ES) was performed and revealed a novel de novo heterozygous nonsense mutation in NFKB2 (c.2611C>T, p.Gln871*) that was not carried by either of her parents. The variant was Sanger sequenced and confirmed to be de novo in the patient. At age 12, she presented with a reactivation of the systemic CMV infection that was associated with severe and progressive nephrotic syndrome with histologic evidence of pedicellar effacement and negative immunofluorescence. To our knowledge, this is the third NF-κB2 deficient patient in which an abnormal NK cell function has been observed, suggesting a role for non-canonical NF-κB2 signaling in NK cell cytotoxicity. NK cell function should be assessed in patients with mutations in the non-canonical NF-κB pathway to explore the risk for systemic viral infections that may lead to severe complications and impact patient survival. Similarly NF-κB2 should be considered in patients with combined immunodeficiency who have aberrant NK cell function. Further studies are needed to characterize the role of NF-κB2 in NK cell cytotoxic function.

9.
Science ; 349(6248): 606-613, 2015 Aug 07.
Article in English | MEDLINE | ID: mdl-26160376

ABSTRACT

Human inborn errors of immunity mediated by the cytokines interleukin-17A and interleukin-17F (IL-17A/F) underlie mucocutaneous candidiasis, whereas inborn errors of interferon-γ (IFN-γ) immunity underlie mycobacterial disease. We report the discovery of bi-allelic RORC loss-of-function mutations in seven individuals from three kindreds of different ethnic origins with both candidiasis and mycobacteriosis. The lack of functional RORγ and RORγT isoforms resulted in the absence of IL-17A/F-producing T cells in these individuals, probably accounting for their chronic candidiasis. Unexpectedly, leukocytes from RORγ- and RORγT-deficient individuals also displayed an impaired IFN-γ response to Mycobacterium. This principally reflected profoundly defective IFN-γ production by circulating γδ T cells and CD4(+)CCR6(+)CXCR3(+) αß T cells. In humans, both mucocutaneous immunity to Candida and systemic immunity to Mycobacterium require RORγ, RORγT, or both.


Subject(s)
Candida albicans/immunology , Candidiasis, Chronic Mucocutaneous/genetics , Immunity/genetics , Nuclear Receptor Subfamily 1, Group F, Member 3/genetics , Severe Combined Immunodeficiency/genetics , Tuberculosis, Bovine/genetics , Tuberculosis, Pulmonary/genetics , Alleles , Animals , Candidiasis, Chronic Mucocutaneous/complications , Candidiasis, Chronic Mucocutaneous/immunology , Cattle , Child , Child, Preschool , DNA Mutational Analysis , Exome/genetics , Female , Gene Rearrangement, alpha-Chain T-Cell Antigen Receptor , Humans , Interferon-gamma/immunology , Interleukin-17/immunology , Mice , Mutation , Mycobacterium bovis/immunology , Mycobacterium bovis/isolation & purification , Mycobacterium tuberculosis/immunology , Mycobacterium tuberculosis/isolation & purification , Pedigree , Receptors, Antigen, T-Cell, alpha-beta/genetics , Receptors, Antigen, T-Cell, alpha-beta/immunology , Receptors, Antigen, T-Cell, gamma-delta/genetics , Receptors, Antigen, T-Cell, gamma-delta/immunology , T-Lymphocytes/immunology , Thymus Gland/abnormalities , Thymus Gland/immunology , Tuberculosis, Bovine/immunology , Tuberculosis, Pulmonary/immunology
10.
Rev. chil. reumatol ; 30(3): 98-118, 2014. tab, ilus
Article in Spanish | LILACS | ID: lil-776847

ABSTRACT

La artritis idiopática juvenil (AIJ) ha sido definida por la Liga Internacional de Asociaciones de Reumatología (ILAR) como artritis de etiología desconocida que se inicia antes de los 16 años y dura por al menos seis semanas, habiendo excluido otras condiciones conocidas. La AIJ es una enfermedad cubierta por el sistema de Garantías Explícitas en Salud (GES) del Ministerio de Salud de Chile desde 2010. La presente guía, desarrollada por el Grupo Pediátrico de la Sociedad Chilena de Reumatología, consiste en una actualización de la Guía Clínica de AIJ 2010, incorporando nuevos protocolos terapéuticos y medicamentos que han demostrado un claro beneficio para niños con AIJ...


Juvenile idiopathic arthritis (JIA) has been defined by the International League of Associations for Rheumatology as arthritis of unknown etiology that begins before the sixteenth birthday and persists for at least 6 weeks with other known conditions excluded. JIA is a disease that is covered by the Explicit Health Guarantees system of the Chilean Ministry of Health since 2010. The present guideline developed by the Pediatric Group of the Chilean Rheumatology Society is an update of the 2010 JIA Clinical Guideline incorporating new treatment protocols and medications that have demonstrated clear benefits in children with JIA...


Subject(s)
Humans , Adolescent , Child, Preschool , Child , Arthritis, Juvenile/diagnosis , Arthritis, Juvenile/therapy , Chile
12.
J Allergy Clin Immunol ; 125(2): 424-432.e8, 2010 Feb.
Article in English | MEDLINE | ID: mdl-20159255

ABSTRACT

BACKGROUND: The hyper-IgE syndrome (HIES) is a primary immunodeficiency characterized by infections of the lung and skin, elevated serum IgE, and involvement of the soft and bony tissues. Recently, HIES has been associated with heterozygous dominant-negative mutations in the signal transducer and activator of transcription 3 (STAT3) and severe reductions of T(H)17 cells. OBJECTIVE: To determine whether there is a correlation between the genotype and the phenotype of patients with HIES and to establish diagnostic criteria to distinguish between STAT3 mutated and STAT3 wild-type patients. METHODS: We collected clinical data, determined T(H)17 cell numbers, and sequenced STAT3 in 100 patients with a strong clinical suspicion of HIES and serum IgE >1000 IU/mL. We explored diagnostic criteria by using a machine-learning approach to identify which features best predict a STAT3 mutation. RESULTS: In 64 patients, we identified 31 different STAT3 mutations, 18 of which were novel. These included mutations at splice sites and outside the previously implicated DNA-binding and Src homology 2 domains. A combination of 5 clinical features predicted STAT3 mutations with 85% accuracy. T(H)17 cells were profoundly reduced in patients harboring STAT3 mutations, whereas 10 of 13 patients without mutations had low (<1%) T(H)17 cells but were distinct by markedly reduced IFN-gamma-producing CD4(+)T cells. CONCLUSION: We propose the following diagnostic guidelines for STAT3-deficient HIES. Possible: IgE >1000IU/mL plus a weighted score of clinical features >30 based on recurrent pneumonia, newborn rash, pathologic bone fractures, characteristic face, and high palate. Probable: These characteristics plus lack of T(H)17 cells or a family history for definitive HIES. Definitive: These characteristics plus a dominant-negative heterozygous mutation in STAT3.


Subject(s)
Job Syndrome/diagnosis , Job Syndrome/genetics , STAT3 Transcription Factor/genetics , Adolescent , Adult , Cell Separation , Child , Child, Preschool , Enzyme-Linked Immunosorbent Assay , Female , Flow Cytometry , Humans , Immunoglobulin E/blood , Infant , Interleukin-17/immunology , Job Syndrome/immunology , Male , Middle Aged , Mutation , Polymerase Chain Reaction , Practice Guidelines as Topic , T-Lymphocytes, Helper-Inducer/immunology , Young Adult
13.
Rev. chil. reumatol ; 24(1): 12-17, 2008. tab
Article in Spanish | LILACS | ID: lil-497954

ABSTRACT

Las artritis inflamatorias del niño constituyen un grupo heterogéneo de enfermedades de presentaciones clínicasdiversas y distintas bases genéticas. Esto ha hecho necesario desarrollar protocolos para el mejor manejo de estos cuadros. En este artículo el Grupo Pediátrico de la Sociedad Chilena de Reumatología ha propuesto una Guía clínica de tratamiento de la Artritis Idiopática Juvenil según los actualesCriterios de Clasificación de ILAR (International League of Associatons for Rheumatology), Edmonton 2001.


Inflammatory arthritis in children is a heterogeneous disease group with several clinical signs and different genetic background. This has brought about the need to develop clinical trials to improve disease management. In this article, the Pediatric Group of the Chilean Rheumatology Society has proposed a Clinical Guide for the medical treatment of Juvenile Idiopathic Arthritis, based on the latest Classification Criteria of the International League of Associations for Rheumatology, ILAR, Edmonton 2001.


Subject(s)
Humans , Child , Arthritis, Juvenile/therapy , Algorithms , Arthritis, Juvenile/classification , Arthritis, Juvenile/diagnosis , Arthritis, Juvenile/epidemiology , Practice Guidelines as Topic , Prognosis , Risk Factors
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